diff options
Diffstat (limited to 'drivers/virtio')
26 files changed, 15259 insertions, 1711 deletions
diff --git a/drivers/virtio/Kconfig b/drivers/virtio/Kconfig index c6683f2e396c..6db5235a7693 100644 --- a/drivers/virtio/Kconfig +++ b/drivers/virtio/Kconfig @@ -1,42 +1,161 @@ +# SPDX-License-Identifier: GPL-2.0-only +config VIRTIO_ANCHOR + bool + config VIRTIO tristate - ---help--- + select VIRTIO_ANCHOR + help This option is selected by any driver which implements the virtio - bus, such as CONFIG_VIRTIO_PCI, CONFIG_VIRTIO_MMIO, CONFIG_LGUEST, - CONFIG_RPMSG or CONFIG_S390_GUEST. + bus, such as CONFIG_VIRTIO_PCI, CONFIG_VIRTIO_MMIO, CONFIG_RPMSG + or CONFIG_S390_GUEST. + +config VIRTIO_PCI_LIB + tristate + help + Modern PCI device implementation. This module implements the + basic probe and control for devices which are based on modern + PCI device with possible vendor specific extensions. Any + module that selects this module must depend on PCI. + +config VIRTIO_PCI_LIB_LEGACY + tristate + help + Legacy PCI device (Virtio PCI Card 0.9.x Draft and older device) + implementation. + This module implements the basic probe and control for devices + which are based on legacy PCI device. Any module that selects this + module must depend on PCI. + +menuconfig VIRTIO_MENU + bool "Virtio drivers" + default y + +if VIRTIO_MENU -menu "Virtio drivers" +config VIRTIO_HARDEN_NOTIFICATION + bool "Harden virtio notification" + depends on BROKEN + help + Enable this to harden the device notifications and suppress + those that happen at a time where notifications are illegal. + + Experimental: Note that several drivers still have issues that + may cause crashes or hangs when correct handling of + notifications is enforced; depending on the subset of + drivers and devices you use, this may or may not work. + + If unsure, say N. config VIRTIO_PCI tristate "PCI driver for virtio devices" depends on PCI + select VIRTIO_PCI_LIB select VIRTIO - ---help--- - This drivers provides support for virtio based paravirtual device + help + This driver provides support for virtio based paravirtual device drivers over PCI. This requires that your VMM has appropriate PCI virtio backends. Most QEMU based VMMs should support these devices (like KVM or Xen). - Currently, the ABI is not considered stable so there is no guarantee - that this version of the driver will work with your VMM. + If unsure, say M. + +config VIRTIO_PCI_ADMIN_LEGACY + bool + depends on VIRTIO_PCI && (X86 || COMPILE_TEST) + default y + +config VIRTIO_PCI_LEGACY + bool "Support for legacy virtio draft 0.9.X and older devices" + default y + depends on VIRTIO_PCI + select VIRTIO_PCI_LIB_LEGACY + help + Virtio PCI Card 0.9.X Draft (circa 2014) and older device support. + + This option enables building a transitional driver, supporting + both devices conforming to Virtio 1 specification, and legacy devices. + If disabled, you get a slightly smaller, non-transitional driver, + with no legacy compatibility. + + So look out into your driveway. Do you have a flying car? If + so, you can happily disable this option and virtio will not + break. Otherwise, leave it set. Unless you're testing what + life will be like in The Future. + + If unsure, say Y. + +config VIRTIO_VDPA + tristate "vDPA driver for virtio devices" + depends on VDPA + select VIRTIO + help + This driver provides support for virtio based paravirtual + device driver over vDPA bus. For this to be useful, you need + an appropriate vDPA device implementation that operates on a + physical device to allow the datapath of virtio to be + offloaded to hardware. If unsure, say M. +config VIRTIO_PMEM + tristate "Support for virtio pmem driver" + depends on VIRTIO + depends on LIBNVDIMM + help + This driver provides access to virtio-pmem devices, storage devices + that are mapped into the physical address space - similar to NVDIMMs + - with a virtio-based flushing interface. + + If unsure, say Y. + config VIRTIO_BALLOON tristate "Virtio balloon driver" depends on VIRTIO - ---help--- + select MEMORY_BALLOON + select PAGE_REPORTING + help This driver supports increasing and decreasing the amount of memory within a KVM guest. If unsure, say M. - config VIRTIO_MMIO +config VIRTIO_MEM + tristate "Virtio mem driver" + depends on X86_64 || ARM64 || RISCV || S390 + depends on VIRTIO + depends on MEMORY_HOTPLUG + depends on MEMORY_HOTREMOVE + depends on CONTIG_ALLOC + depends on EXCLUSIVE_SYSTEM_RAM + help + This driver provides access to virtio-mem paravirtualized memory + devices, allowing to hotplug and hotunplug memory. + + This driver currently supports x86-64, arm64, riscv and s390. + Although it should compile on other architectures that implement + memory hot(un)plug, architecture-specific and/or common + code changes may be required for virtio-mem, kdump and kexec to + work as expected. + + If unsure, say M. + +config VIRTIO_INPUT + tristate "Virtio input driver" + depends on VIRTIO + depends on INPUT + help + This driver supports virtio input devices such as + keyboards, mice and tablets. + + If unsure, say M. + +config VIRTIO_MMIO tristate "Platform bus driver for memory mapped virtio devices" - depends on HAS_IOMEM - select VIRTIO - ---help--- - This drivers provides support for memory mapped virtio + depends on HAS_IOMEM && HAS_DMA + select VIRTIO + help + This drivers provides support for memory mapped virtio platform device driver. If unsure, say N. @@ -44,12 +163,93 @@ config VIRTIO_BALLOON config VIRTIO_MMIO_CMDLINE_DEVICES bool "Memory mapped virtio devices parameter parsing" depends on VIRTIO_MMIO - ---help--- + help Allow virtio-mmio devices instantiation via the kernel command line or module parameters. Be aware that using incorrect parameters (base address in particular) can crash your system - you have been warned. - See Documentation/kernel-parameters.txt for details. + See Documentation/admin-guide/kernel-parameters.rst for details. If unsure, say 'N'. -endmenu +config VIRTIO_DMA_SHARED_BUFFER + tristate + depends on DMA_SHARED_BUFFER + help + This option adds a flavor of dma buffers that are backed by + virtio resources. + +config VIRTIO_DEBUG + bool "Debug facilities" + depends on VIRTIO + help + Enable this to expose debug facilities over debugfs. + This allows to debug features, to see what features the device + advertises and to set filter for features used by driver. + + If unsure, say N. + +config VIRTIO_RTC + tristate "Virtio RTC driver" + depends on VIRTIO + depends on PTP_1588_CLOCK_OPTIONAL + help + This driver provides current time from a Virtio RTC device. The driver + provides the time through one or more clocks. The Virtio RTC PTP + clocks and/or the Real Time Clock driver for Virtio RTC must be + enabled to expose the clocks to userspace. + + To compile this code as a module, choose M here: the module will be + called virtio_rtc. + + If unsure, say M. + +if VIRTIO_RTC + +comment "WARNING: Consider enabling VIRTIO_RTC_PTP and/or VIRTIO_RTC_CLASS." + depends on !VIRTIO_RTC_PTP && !VIRTIO_RTC_CLASS + +comment "Enable PTP_1588_CLOCK in order to enable VIRTIO_RTC_PTP." + depends on PTP_1588_CLOCK=n + +config VIRTIO_RTC_PTP + bool "Virtio RTC PTP clocks" + default y + depends on PTP_1588_CLOCK + help + This exposes any Virtio RTC clocks as PTP Hardware Clocks (PHCs) to + userspace. The PHC sysfs attribute "clock_name" describes the clock + type. + + If unsure, say Y. + +config VIRTIO_RTC_ARM + bool "Virtio RTC cross-timestamping using Arm Generic Timer" + default y + depends on VIRTIO_RTC_PTP && ARM_ARCH_TIMER + help + This enables Virtio RTC cross-timestamping using the Arm Generic Timer. + It only has an effect if the Virtio RTC device also supports this. The + cross-timestamp is available through the PTP clock driver precise + cross-timestamp ioctl (PTP_SYS_OFFSET_PRECISE2 aka + PTP_SYS_OFFSET_PRECISE). + + If unsure, say Y. + +comment "Enable RTC_CLASS in order to enable VIRTIO_RTC_CLASS." + depends on RTC_CLASS=n + +config VIRTIO_RTC_CLASS + bool "Real Time Clock driver for Virtio RTC" + default y + depends on RTC_CLASS + help + This exposes the Virtio RTC UTC-like clock as a Linux Real Time Clock. + It only has an effect if the Virtio RTC device has a UTC-like clock + which smears leap seconds to avoid steps. The Real Time Clock is + read-only, and may support setting an alarm. + + If unsure, say Y. + +endif # VIRTIO_RTC + +endif # VIRTIO_MENU diff --git a/drivers/virtio/Makefile b/drivers/virtio/Makefile index 9076635697bb..eefcfe90d6b8 100644 --- a/drivers/virtio/Makefile +++ b/drivers/virtio/Makefile @@ -1,4 +1,21 @@ +# SPDX-License-Identifier: GPL-2.0 obj-$(CONFIG_VIRTIO) += virtio.o virtio_ring.o +obj-$(CONFIG_VIRTIO_ANCHOR) += virtio_anchor.o +obj-$(CONFIG_VIRTIO_PCI_LIB) += virtio_pci_modern_dev.o +obj-$(CONFIG_VIRTIO_PCI_LIB_LEGACY) += virtio_pci_legacy_dev.o obj-$(CONFIG_VIRTIO_MMIO) += virtio_mmio.o obj-$(CONFIG_VIRTIO_PCI) += virtio_pci.o +virtio_pci-y := virtio_pci_modern.o virtio_pci_common.o +virtio_pci-$(CONFIG_VIRTIO_PCI_LEGACY) += virtio_pci_legacy.o +virtio_pci-$(CONFIG_VIRTIO_PCI_ADMIN_LEGACY) += virtio_pci_admin_legacy_io.o obj-$(CONFIG_VIRTIO_BALLOON) += virtio_balloon.o +obj-$(CONFIG_VIRTIO_INPUT) += virtio_input.o +obj-$(CONFIG_VIRTIO_VDPA) += virtio_vdpa.o +obj-$(CONFIG_VIRTIO_MEM) += virtio_mem.o +obj-$(CONFIG_VIRTIO_DMA_SHARED_BUFFER) += virtio_dma_buf.o +obj-$(CONFIG_VIRTIO_DEBUG) += virtio_debug.o +obj-$(CONFIG_VIRTIO_RTC) += virtio_rtc.o +virtio_rtc-y := virtio_rtc_driver.o +virtio_rtc-$(CONFIG_VIRTIO_RTC_PTP) += virtio_rtc_ptp.o +virtio_rtc-$(CONFIG_VIRTIO_RTC_ARM) += virtio_rtc_arm.o +virtio_rtc-$(CONFIG_VIRTIO_RTC_CLASS) += virtio_rtc_class.o diff --git a/drivers/virtio/config.c b/drivers/virtio/config.c deleted file mode 100644 index f70bcd2ff98f..000000000000 --- a/drivers/virtio/config.c +++ /dev/null @@ -1,12 +0,0 @@ -/* Configuration space parsing helpers for virtio. - * - * The configuration is [type][len][... len bytes ...] fields. - * - * Copyright 2007 Rusty Russell, IBM Corporation. - * GPL v2 or later. - */ -#include <linux/err.h> -#include <linux/virtio.h> -#include <linux/virtio_config.h> -#include <linux/bug.h> - diff --git a/drivers/virtio/virtio.c b/drivers/virtio/virtio.c index ee59b74768d9..5bdc6b82b30b 100644 --- a/drivers/virtio/virtio.c +++ b/drivers/virtio/virtio.c @@ -1,8 +1,12 @@ +// SPDX-License-Identifier: GPL-2.0-only #include <linux/virtio.h> #include <linux/spinlock.h> #include <linux/virtio_config.h> +#include <linux/virtio_anchor.h> #include <linux/module.h> #include <linux/idr.h> +#include <linux/of.h> +#include <uapi/linux/virtio_ids.h> /* Unique numbering for virtio devices. */ static DEFINE_IDA(virtio_index_ida); @@ -11,27 +15,35 @@ static ssize_t device_show(struct device *_d, struct device_attribute *attr, char *buf) { struct virtio_device *dev = dev_to_virtio(_d); - return sprintf(buf, "0x%04x\n", dev->id.device); + return sysfs_emit(buf, "0x%04x\n", dev->id.device); } +static DEVICE_ATTR_RO(device); + static ssize_t vendor_show(struct device *_d, struct device_attribute *attr, char *buf) { struct virtio_device *dev = dev_to_virtio(_d); - return sprintf(buf, "0x%04x\n", dev->id.vendor); + return sysfs_emit(buf, "0x%04x\n", dev->id.vendor); } +static DEVICE_ATTR_RO(vendor); + static ssize_t status_show(struct device *_d, struct device_attribute *attr, char *buf) { struct virtio_device *dev = dev_to_virtio(_d); - return sprintf(buf, "0x%08x\n", dev->config->get_status(dev)); + return sysfs_emit(buf, "0x%08x\n", dev->config->get_status(dev)); } +static DEVICE_ATTR_RO(status); + static ssize_t modalias_show(struct device *_d, struct device_attribute *attr, char *buf) { struct virtio_device *dev = dev_to_virtio(_d); - return sprintf(buf, "virtio:d%08Xv%08X\n", + return sysfs_emit(buf, "virtio:d%08Xv%08X\n", dev->id.device, dev->id.vendor); } +static DEVICE_ATTR_RO(modalias); + static ssize_t features_show(struct device *_d, struct device_attribute *attr, char *buf) { @@ -41,20 +53,23 @@ static ssize_t features_show(struct device *_d, /* We actually represent this as a bitstring, as it could be * arbitrary length in future. */ - for (i = 0; i < ARRAY_SIZE(dev->features)*BITS_PER_LONG; i++) - len += sprintf(buf+len, "%c", - test_bit(i, dev->features) ? '1' : '0'); - len += sprintf(buf+len, "\n"); + for (i = 0; i < VIRTIO_FEATURES_BITS; i++) + len += sysfs_emit_at(buf, len, "%c", + __virtio_test_bit(dev, i) ? '1' : '0'); + len += sysfs_emit_at(buf, len, "\n"); return len; } -static struct device_attribute virtio_dev_attrs[] = { - __ATTR_RO(device), - __ATTR_RO(vendor), - __ATTR_RO(status), - __ATTR_RO(modalias), - __ATTR_RO(features), - __ATTR_NULL +static DEVICE_ATTR_RO(features); + +static struct attribute *virtio_dev_attrs[] = { + &dev_attr_device.attr, + &dev_attr_vendor.attr, + &dev_attr_status.attr, + &dev_attr_modalias.attr, + &dev_attr_features.attr, + NULL, }; +ATTRIBUTE_GROUPS(virtio_dev); static inline int virtio_id_match(const struct virtio_device *dev, const struct virtio_device_id *id) @@ -67,7 +82,7 @@ static inline int virtio_id_match(const struct virtio_device *dev, /* This looks through all the IDs a driver claims to support. If any of them * match, we return 1 and the kernel will call virtio_dev_probe(). */ -static int virtio_dev_match(struct device *_dv, struct device_driver *_dr) +static int virtio_dev_match(struct device *_dv, const struct device_driver *_dr) { unsigned int i; struct virtio_device *dev = dev_to_virtio(_dv); @@ -80,19 +95,14 @@ static int virtio_dev_match(struct device *_dv, struct device_driver *_dr) return 0; } -static int virtio_uevent(struct device *_dv, struct kobj_uevent_env *env) +static int virtio_uevent(const struct device *_dv, struct kobj_uevent_env *env) { - struct virtio_device *dev = dev_to_virtio(_dv); + const struct virtio_device *dev = dev_to_virtio(_dv); return add_uevent_var(env, "MODALIAS=virtio:d%08Xv%08X", dev->id.device, dev->id.vendor); } -static void add_status(struct virtio_device *dev, unsigned status) -{ - dev->config->set_status(dev, dev->config->get_status(dev) | status); -} - void virtio_check_driver_offered_feature(const struct virtio_device *vdev, unsigned int fbit) { @@ -102,83 +112,350 @@ void virtio_check_driver_offered_feature(const struct virtio_device *vdev, for (i = 0; i < drv->feature_table_size; i++) if (drv->feature_table[i] == fbit) return; + + if (drv->feature_table_legacy) { + for (i = 0; i < drv->feature_table_size_legacy; i++) + if (drv->feature_table_legacy[i] == fbit) + return; + } + BUG(); } EXPORT_SYMBOL_GPL(virtio_check_driver_offered_feature); +static void __virtio_config_changed(struct virtio_device *dev) +{ + struct virtio_driver *drv = drv_to_virtio(dev->dev.driver); + + if (!dev->config_core_enabled || dev->config_driver_disabled) + dev->config_change_pending = true; + else if (drv && drv->config_changed) { + drv->config_changed(dev); + dev->config_change_pending = false; + } +} + +void virtio_config_changed(struct virtio_device *dev) +{ + unsigned long flags; + + spin_lock_irqsave(&dev->config_lock, flags); + __virtio_config_changed(dev); + spin_unlock_irqrestore(&dev->config_lock, flags); +} +EXPORT_SYMBOL_GPL(virtio_config_changed); + +/** + * virtio_config_driver_disable - disable config change reporting by drivers + * @dev: the device to disable + * + * This is only allowed to be called by a driver and disabling can't + * be nested. + */ +void virtio_config_driver_disable(struct virtio_device *dev) +{ + spin_lock_irq(&dev->config_lock); + dev->config_driver_disabled = true; + spin_unlock_irq(&dev->config_lock); +} +EXPORT_SYMBOL_GPL(virtio_config_driver_disable); + +/** + * virtio_config_driver_enable - enable config change reporting by drivers + * @dev: the device to enable + * + * This is only allowed to be called by a driver and enabling can't + * be nested. + */ +void virtio_config_driver_enable(struct virtio_device *dev) +{ + spin_lock_irq(&dev->config_lock); + dev->config_driver_disabled = false; + if (dev->config_change_pending) + __virtio_config_changed(dev); + spin_unlock_irq(&dev->config_lock); +} +EXPORT_SYMBOL_GPL(virtio_config_driver_enable); + +static void virtio_config_core_disable(struct virtio_device *dev) +{ + spin_lock_irq(&dev->config_lock); + dev->config_core_enabled = false; + spin_unlock_irq(&dev->config_lock); +} + +static void virtio_config_core_enable(struct virtio_device *dev) +{ + spin_lock_irq(&dev->config_lock); + dev->config_core_enabled = true; + if (dev->config_change_pending) + __virtio_config_changed(dev); + spin_unlock_irq(&dev->config_lock); +} + +void virtio_add_status(struct virtio_device *dev, unsigned int status) +{ + might_sleep(); + dev->config->set_status(dev, dev->config->get_status(dev) | status); +} +EXPORT_SYMBOL_GPL(virtio_add_status); + +/* Do some validation, then set FEATURES_OK */ +static int virtio_features_ok(struct virtio_device *dev) +{ + unsigned int status; + + might_sleep(); + + if (virtio_check_mem_acc_cb(dev)) { + if (!virtio_has_feature(dev, VIRTIO_F_VERSION_1)) { + dev_warn(&dev->dev, + "device must provide VIRTIO_F_VERSION_1\n"); + return -ENODEV; + } + + if (!virtio_has_feature(dev, VIRTIO_F_ACCESS_PLATFORM)) { + dev_warn(&dev->dev, + "device must provide VIRTIO_F_ACCESS_PLATFORM\n"); + return -ENODEV; + } + } + + if (!virtio_has_feature(dev, VIRTIO_F_VERSION_1)) + return 0; + + virtio_add_status(dev, VIRTIO_CONFIG_S_FEATURES_OK); + status = dev->config->get_status(dev); + if (!(status & VIRTIO_CONFIG_S_FEATURES_OK)) { + dev_err(&dev->dev, "virtio: device refuses features: %x\n", + status); + return -ENODEV; + } + return 0; +} + +/** + * virtio_reset_device - quiesce device for removal + * @dev: the device to reset + * + * Prevents device from sending interrupts and accessing memory. + * + * Generally used for cleanup during driver / device removal. + * + * Once this has been invoked, caller must ensure that + * virtqueue_notify / virtqueue_kick are not in progress. + * + * Note: this guarantees that vq callbacks are not in progress, however caller + * is responsible for preventing access from other contexts, such as a system + * call/workqueue/bh. Invoking virtio_break_device then flushing any such + * contexts is one way to handle that. + * */ +void virtio_reset_device(struct virtio_device *dev) +{ +#ifdef CONFIG_VIRTIO_HARDEN_NOTIFICATION + /* + * The below virtio_synchronize_cbs() guarantees that any + * interrupt for this line arriving after + * virtio_synchronize_vqs() has completed is guaranteed to see + * vq->broken as true. + */ + virtio_break_device(dev); + virtio_synchronize_cbs(dev); +#endif + + dev->config->reset(dev); +} +EXPORT_SYMBOL_GPL(virtio_reset_device); + static int virtio_dev_probe(struct device *_d) { int err, i; struct virtio_device *dev = dev_to_virtio(_d); struct virtio_driver *drv = drv_to_virtio(dev->dev.driver); - u32 device_features; + u64 device_features[VIRTIO_FEATURES_U64S]; + u64 driver_features[VIRTIO_FEATURES_U64S]; + u64 driver_features_legacy; /* We have a driver! */ - add_status(dev, VIRTIO_CONFIG_S_DRIVER); + virtio_add_status(dev, VIRTIO_CONFIG_S_DRIVER); /* Figure out what features the device supports. */ - device_features = dev->config->get_features(dev); + virtio_get_features(dev, device_features); - /* Features supported by both device and driver into dev->features. */ - memset(dev->features, 0, sizeof(dev->features)); + /* Figure out what features the driver supports. */ + virtio_features_zero(driver_features); for (i = 0; i < drv->feature_table_size; i++) { unsigned int f = drv->feature_table[i]; - BUG_ON(f >= 32); - if (device_features & (1 << f)) - set_bit(f, dev->features); + if (!WARN_ON_ONCE(f >= VIRTIO_FEATURES_BITS)) + virtio_features_set_bit(driver_features, f); } + /* Some drivers have a separate feature table for virtio v1.0 */ + if (drv->feature_table_legacy) { + driver_features_legacy = 0; + for (i = 0; i < drv->feature_table_size_legacy; i++) { + unsigned int f = drv->feature_table_legacy[i]; + if (!WARN_ON_ONCE(f >= 64)) + driver_features_legacy |= (1ULL << f); + } + } else { + driver_features_legacy = driver_features[0]; + } + + if (virtio_features_test_bit(device_features, VIRTIO_F_VERSION_1)) { + for (i = 0; i < VIRTIO_FEATURES_U64S; ++i) + dev->features_array[i] = driver_features[i] & + device_features[i]; + } else { + virtio_features_from_u64(dev->features_array, + driver_features_legacy & + device_features[0]); + } + + /* When debugging, user may filter some features by hand. */ + virtio_debug_device_filter_features(dev); + /* Transport features always preserved to pass to finalize_features. */ for (i = VIRTIO_TRANSPORT_F_START; i < VIRTIO_TRANSPORT_F_END; i++) - if (device_features & (1 << i)) - set_bit(i, dev->features); + if (virtio_features_test_bit(device_features, i)) + __virtio_set_bit(dev, i); + + err = dev->config->finalize_features(dev); + if (err) + goto err; + + if (drv->validate) { + u64 features[VIRTIO_FEATURES_U64S]; + + virtio_features_copy(features, dev->features_array); + err = drv->validate(dev); + if (err) + goto err; + + /* Did validation change any features? Then write them again. */ + if (!virtio_features_equal(features, dev->features_array)) { + err = dev->config->finalize_features(dev); + if (err) + goto err; + } + } - dev->config->finalize_features(dev); + err = virtio_features_ok(dev); + if (err) + goto err; err = drv->probe(dev); if (err) - add_status(dev, VIRTIO_CONFIG_S_FAILED); - else { - add_status(dev, VIRTIO_CONFIG_S_DRIVER_OK); - if (drv->scan) - drv->scan(dev); - } + goto err; + + /* If probe didn't do it, mark device DRIVER_OK ourselves. */ + if (!(dev->config->get_status(dev) & VIRTIO_CONFIG_S_DRIVER_OK)) + virtio_device_ready(dev); + + if (drv->scan) + drv->scan(dev); + + virtio_config_core_enable(dev); + return 0; + +err: + virtio_add_status(dev, VIRTIO_CONFIG_S_FAILED); return err; + } -static int virtio_dev_remove(struct device *_d) +static void virtio_dev_remove(struct device *_d) { struct virtio_device *dev = dev_to_virtio(_d); struct virtio_driver *drv = drv_to_virtio(dev->dev.driver); + virtio_config_core_disable(dev); + drv->remove(dev); /* Driver should have reset device. */ WARN_ON_ONCE(dev->config->get_status(dev)); /* Acknowledge the device's existence again. */ - add_status(dev, VIRTIO_CONFIG_S_ACKNOWLEDGE); - return 0; + virtio_add_status(dev, VIRTIO_CONFIG_S_ACKNOWLEDGE); + + of_node_put(dev->dev.of_node); +} + +/* + * virtio_irq_get_affinity - get IRQ affinity mask for device + * @_d: ptr to dev structure + * @irq_vec: interrupt vector number + * + * Return the CPU affinity mask for @_d and @irq_vec. + */ +static const struct cpumask *virtio_irq_get_affinity(struct device *_d, + unsigned int irq_vec) +{ + struct virtio_device *dev = dev_to_virtio(_d); + + if (!dev->config->get_vq_affinity) + return NULL; + + return dev->config->get_vq_affinity(dev, irq_vec); +} + +static void virtio_dev_shutdown(struct device *_d) +{ + struct virtio_device *dev = dev_to_virtio(_d); + struct virtio_driver *drv = drv_to_virtio(dev->dev.driver); + + /* + * Stop accesses to or from the device. + * We only need to do it if there's a driver - no accesses otherwise. + */ + if (!drv) + return; + + /* If the driver has its own shutdown method, use that. */ + if (drv->shutdown) { + drv->shutdown(dev); + return; + } + + /* + * Some devices get wedged if you kick them after they are + * reset. Mark all vqs as broken to make sure we don't. + */ + virtio_break_device(dev); + /* + * Guarantee that any callback will see vq->broken as true. + */ + virtio_synchronize_cbs(dev); + /* + * As IOMMUs are reset on shutdown, this will block device access to memory. + * Some devices get wedged if this happens, so reset to make sure it does not. + */ + dev->config->reset(dev); } -static struct bus_type virtio_bus = { +static const struct bus_type virtio_bus = { .name = "virtio", .match = virtio_dev_match, - .dev_attrs = virtio_dev_attrs, + .dev_groups = virtio_dev_groups, .uevent = virtio_uevent, .probe = virtio_dev_probe, .remove = virtio_dev_remove, + .irq_get_affinity = virtio_irq_get_affinity, + .shutdown = virtio_dev_shutdown, }; -int register_virtio_driver(struct virtio_driver *driver) +int __register_virtio_driver(struct virtio_driver *driver, struct module *owner) { /* Catch this early. */ BUG_ON(driver->feature_table_size && !driver->feature_table); driver->driver.bus = &virtio_bus; + driver->driver.owner = owner; + return driver_register(&driver->driver); } -EXPORT_SYMBOL_GPL(register_virtio_driver); +EXPORT_SYMBOL_GPL(__register_virtio_driver); void unregister_virtio_driver(struct virtio_driver *driver) { @@ -186,60 +463,268 @@ void unregister_virtio_driver(struct virtio_driver *driver) } EXPORT_SYMBOL_GPL(unregister_virtio_driver); +static int virtio_device_of_init(struct virtio_device *dev) +{ + struct device_node *np, *pnode = dev_of_node(dev->dev.parent); + char compat[] = "virtio,deviceXXXXXXXX"; + int ret, count; + + if (!pnode) + return 0; + + count = of_get_available_child_count(pnode); + if (!count) + return 0; + + /* There can be only 1 child node */ + if (WARN_ON(count > 1)) + return -EINVAL; + + np = of_get_next_available_child(pnode, NULL); + if (WARN_ON(!np)) + return -ENODEV; + + ret = snprintf(compat, sizeof(compat), "virtio,device%x", dev->id.device); + BUG_ON(ret >= sizeof(compat)); + + /* + * On powerpc/pseries virtio devices are PCI devices so PCI + * vendor/device ids play the role of the "compatible" property. + * Simply don't init of_node in this case. + */ + if (!of_device_is_compatible(np, compat)) { + ret = 0; + goto out; + } + + dev->dev.of_node = np; + return 0; + +out: + of_node_put(np); + return ret; +} + +/** + * register_virtio_device - register virtio device + * @dev : virtio device to be registered + * + * On error, the caller must call put_device on &@dev->dev (and not kfree), + * as another code path may have obtained a reference to @dev. + * + * Returns: 0 on success, -error on failure + */ int register_virtio_device(struct virtio_device *dev) { int err; dev->dev.bus = &virtio_bus; + device_initialize(&dev->dev); /* Assign a unique device index and hence name. */ - err = ida_simple_get(&virtio_index_ida, 0, 0, GFP_KERNEL); + err = ida_alloc(&virtio_index_ida, GFP_KERNEL); if (err < 0) goto out; dev->index = err; - dev_set_name(&dev->dev, "virtio%u", dev->index); + err = dev_set_name(&dev->dev, "virtio%u", dev->index); + if (err) + goto out_ida_remove; + + err = virtio_device_of_init(dev); + if (err) + goto out_ida_remove; + + spin_lock_init(&dev->config_lock); + dev->config_driver_disabled = false; + dev->config_core_enabled = false; + dev->config_change_pending = false; + + INIT_LIST_HEAD(&dev->vqs); + spin_lock_init(&dev->vqs_list_lock); /* We always start by resetting the device, in case a previous * driver messed it up. This also tests that code path a little. */ - dev->config->reset(dev); + virtio_reset_device(dev); /* Acknowledge that we've seen the device. */ - add_status(dev, VIRTIO_CONFIG_S_ACKNOWLEDGE); + virtio_add_status(dev, VIRTIO_CONFIG_S_ACKNOWLEDGE); - INIT_LIST_HEAD(&dev->vqs); + virtio_debug_device_init(dev); - /* device_register() causes the bus infrastructure to look for a - * matching driver. */ - err = device_register(&dev->dev); -out: + /* + * device_add() causes the bus infrastructure to look for a matching + * driver. + */ + err = device_add(&dev->dev); if (err) - add_status(dev, VIRTIO_CONFIG_S_FAILED); + goto out_of_node_put; + + return 0; + +out_of_node_put: + of_node_put(dev->dev.of_node); +out_ida_remove: + ida_free(&virtio_index_ida, dev->index); +out: + virtio_add_status(dev, VIRTIO_CONFIG_S_FAILED); return err; } EXPORT_SYMBOL_GPL(register_virtio_device); +bool is_virtio_device(struct device *dev) +{ + return dev->bus == &virtio_bus; +} +EXPORT_SYMBOL_GPL(is_virtio_device); + void unregister_virtio_device(struct virtio_device *dev) { int index = dev->index; /* save for after device release */ device_unregister(&dev->dev); - ida_simple_remove(&virtio_index_ida, index); + virtio_debug_device_exit(dev); + ida_free(&virtio_index_ida, index); } EXPORT_SYMBOL_GPL(unregister_virtio_device); +static int virtio_device_restore_priv(struct virtio_device *dev, bool restore) +{ + struct virtio_driver *drv = drv_to_virtio(dev->dev.driver); + int ret; + + /* We always start by resetting the device, in case a previous + * driver messed it up. */ + virtio_reset_device(dev); + + /* Acknowledge that we've seen the device. */ + virtio_add_status(dev, VIRTIO_CONFIG_S_ACKNOWLEDGE); + + /* Maybe driver failed before freeze. + * Restore the failed status, for debugging. */ + if (dev->failed) + virtio_add_status(dev, VIRTIO_CONFIG_S_FAILED); + + if (!drv) + return 0; + + /* We have a driver! */ + virtio_add_status(dev, VIRTIO_CONFIG_S_DRIVER); + + ret = dev->config->finalize_features(dev); + if (ret) + goto err; + + ret = virtio_features_ok(dev); + if (ret) + goto err; + + if (restore) { + if (drv->restore) { + ret = drv->restore(dev); + if (ret) + goto err; + } + } else { + ret = drv->reset_done(dev); + if (ret) + goto err; + } + + /* If restore didn't do it, mark device DRIVER_OK ourselves. */ + if (!(dev->config->get_status(dev) & VIRTIO_CONFIG_S_DRIVER_OK)) + virtio_device_ready(dev); + + virtio_config_core_enable(dev); + + return 0; + +err: + virtio_add_status(dev, VIRTIO_CONFIG_S_FAILED); + return ret; +} + +#ifdef CONFIG_PM_SLEEP +int virtio_device_freeze(struct virtio_device *dev) +{ + struct virtio_driver *drv = drv_to_virtio(dev->dev.driver); + int ret; + + virtio_config_core_disable(dev); + + dev->failed = dev->config->get_status(dev) & VIRTIO_CONFIG_S_FAILED; + + if (drv && drv->freeze) { + ret = drv->freeze(dev); + if (ret) { + virtio_config_core_enable(dev); + return ret; + } + } + + return 0; +} +EXPORT_SYMBOL_GPL(virtio_device_freeze); + +int virtio_device_restore(struct virtio_device *dev) +{ + return virtio_device_restore_priv(dev, true); +} +EXPORT_SYMBOL_GPL(virtio_device_restore); +#endif + +int virtio_device_reset_prepare(struct virtio_device *dev) +{ + struct virtio_driver *drv = drv_to_virtio(dev->dev.driver); + int ret; + + if (!drv || !drv->reset_prepare) + return -EOPNOTSUPP; + + virtio_config_core_disable(dev); + + dev->failed = dev->config->get_status(dev) & VIRTIO_CONFIG_S_FAILED; + + ret = drv->reset_prepare(dev); + if (ret) { + virtio_config_core_enable(dev); + return ret; + } + + return 0; +} +EXPORT_SYMBOL_GPL(virtio_device_reset_prepare); + +int virtio_device_reset_done(struct virtio_device *dev) +{ + struct virtio_driver *drv = drv_to_virtio(dev->dev.driver); + + if (!drv || !drv->reset_done) + return -EOPNOTSUPP; + + return virtio_device_restore_priv(dev, false); +} +EXPORT_SYMBOL_GPL(virtio_device_reset_done); + static int virtio_init(void) { + BUILD_BUG_ON(offsetof(struct virtio_device, features) != + offsetof(struct virtio_device, features_array[0])); + if (bus_register(&virtio_bus) != 0) panic("virtio bus registration failed"); + virtio_debug_init(); return 0; } static void __exit virtio_exit(void) { + virtio_debug_exit(); bus_unregister(&virtio_bus); + ida_destroy(&virtio_index_ida); } core_initcall(virtio_init); module_exit(virtio_exit); +MODULE_DESCRIPTION("Virtio core interface"); MODULE_LICENSE("GPL"); diff --git a/drivers/virtio/virtio_anchor.c b/drivers/virtio/virtio_anchor.c new file mode 100644 index 000000000000..4d6a5d269b55 --- /dev/null +++ b/drivers/virtio/virtio_anchor.c @@ -0,0 +1,18 @@ +// SPDX-License-Identifier: GPL-2.0-only +#include <linux/virtio.h> +#include <linux/virtio_anchor.h> + +bool virtio_require_restricted_mem_acc(struct virtio_device *dev) +{ + return true; +} +EXPORT_SYMBOL_GPL(virtio_require_restricted_mem_acc); + +static bool virtio_no_restricted_mem_acc(struct virtio_device *dev) +{ + return false; +} + +bool (*virtio_check_mem_acc_cb)(struct virtio_device *dev) = + virtio_no_restricted_mem_acc; +EXPORT_SYMBOL_GPL(virtio_check_mem_acc_cb); diff --git a/drivers/virtio/virtio_balloon.c b/drivers/virtio/virtio_balloon.c index 1f572c00a1be..74fe59f5a78c 100644 --- a/drivers/virtio/virtio_balloon.c +++ b/drivers/virtio/virtio_balloon.c @@ -1,52 +1,91 @@ +// SPDX-License-Identifier: GPL-2.0-or-later /* * Virtio balloon implementation, inspired by Dor Laor and Marcelo * Tosatti's implementations. * * Copyright 2008 Rusty Russell IBM Corporation - * - * This program is free software; you can redistribute it and/or modify - * it under the terms of the GNU General Public License as published by - * the Free Software Foundation; either version 2 of the License, or - * (at your option) any later version. - * - * This program is distributed in the hope that it will be useful, - * but WITHOUT ANY WARRANTY; without even the implied warranty of - * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the - * GNU General Public License for more details. - * - * You should have received a copy of the GNU General Public License - * along with this program; if not, write to the Free Software - * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA */ #include <linux/virtio.h> #include <linux/virtio_balloon.h> #include <linux/swap.h> -#include <linux/kthread.h> -#include <linux/freezer.h> +#include <linux/workqueue.h> #include <linux/delay.h> #include <linux/slab.h> #include <linux/module.h> #include <linux/balloon_compaction.h> +#include <linux/oom.h> +#include <linux/wait.h> +#include <linux/mm.h> +#include <linux/page_reporting.h> /* * Balloon device works in 4K page units. So each page is pointed to by * multiple balloon pages. All memory counters in this driver are in balloon * page units. */ -#define VIRTIO_BALLOON_PAGES_PER_PAGE (unsigned)(PAGE_SIZE >> VIRTIO_BALLOON_PFN_SHIFT) +#define VIRTIO_BALLOON_PAGES_PER_PAGE (unsigned int)(PAGE_SIZE >> VIRTIO_BALLOON_PFN_SHIFT) #define VIRTIO_BALLOON_ARRAY_PFNS_MAX 256 +/* Maximum number of (4k) pages to deflate on OOM notifications. */ +#define VIRTIO_BALLOON_OOM_NR_PAGES 256 +#define VIRTIO_BALLOON_OOM_NOTIFY_PRIORITY 80 + +#define VIRTIO_BALLOON_FREE_PAGE_ALLOC_FLAG (__GFP_NORETRY | __GFP_NOWARN | \ + __GFP_NOMEMALLOC) +/* The order of free page blocks to report to host */ +#define VIRTIO_BALLOON_HINT_BLOCK_ORDER MAX_PAGE_ORDER +/* The size of a free page block in bytes */ +#define VIRTIO_BALLOON_HINT_BLOCK_BYTES \ + (1 << (VIRTIO_BALLOON_HINT_BLOCK_ORDER + PAGE_SHIFT)) +#define VIRTIO_BALLOON_HINT_BLOCK_PAGES (1 << VIRTIO_BALLOON_HINT_BLOCK_ORDER) + +enum virtio_balloon_vq { + VIRTIO_BALLOON_VQ_INFLATE, + VIRTIO_BALLOON_VQ_DEFLATE, + VIRTIO_BALLOON_VQ_STATS, + VIRTIO_BALLOON_VQ_FREE_PAGE, + VIRTIO_BALLOON_VQ_REPORTING, + VIRTIO_BALLOON_VQ_MAX +}; -struct virtio_balloon -{ - struct virtio_device *vdev; - struct virtqueue *inflate_vq, *deflate_vq, *stats_vq; - - /* Where the ballooning thread waits for config to change. */ - wait_queue_head_t config_change; +enum virtio_balloon_config_read { + VIRTIO_BALLOON_CONFIG_READ_CMD_ID = 0, +}; - /* The thread servicing the balloon. */ - struct task_struct *thread; +struct virtio_balloon { + struct virtio_device *vdev; + struct virtqueue *inflate_vq, *deflate_vq, *stats_vq, *free_page_vq; + + /* Balloon's own wq for cpu-intensive work items */ + struct workqueue_struct *balloon_wq; + /* The free page reporting work item submitted to the balloon wq */ + struct work_struct report_free_page_work; + + /* The balloon servicing is delegated to a freezable workqueue. */ + struct work_struct update_balloon_stats_work; + struct work_struct update_balloon_size_work; + + /* Prevent updating balloon when it is being canceled. */ + spinlock_t stop_update_lock; + bool stop_update; + /* Bitmap to indicate if reading the related config fields are needed */ + unsigned long config_read_bitmap; + + /* The list of allocated free pages, waiting to be given back to mm */ + struct list_head free_page_list; + spinlock_t free_page_list_lock; + /* The number of free page blocks on the above list */ + unsigned long num_free_page_blocks; + /* + * The cmd id received from host. + * Read it via virtio_balloon_cmd_id_received to get the latest value + * sent from host. + */ + u32 cmd_id_received_cache; + /* The cmd id that is actively in use */ + __virtio32 cmd_id_active; + /* Buffer to store the stop sign */ + __virtio32 cmd_id_stop; /* Waiting for host to ack the pages we released. */ wait_queue_head_t acked; @@ -59,21 +98,38 @@ struct virtio_balloon * Each page on this list adds VIRTIO_BALLOON_PAGES_PER_PAGE * to num_pages above. */ - struct balloon_dev_info *vb_dev_info; + struct balloon_dev_info vb_dev_info; /* Synchronize access/update to this struct virtio_balloon elements */ struct mutex balloon_lock; /* The array of pfns we tell the Host about. */ unsigned int num_pfns; - u32 pfns[VIRTIO_BALLOON_ARRAY_PFNS_MAX]; + __virtio32 pfns[VIRTIO_BALLOON_ARRAY_PFNS_MAX]; /* Memory statistics */ - int need_stats_update; struct virtio_balloon_stat stats[VIRTIO_BALLOON_S_NR]; + + /* Shrinker to return free pages - VIRTIO_BALLOON_F_FREE_PAGE_HINT */ + struct shrinker *shrinker; + + /* OOM notifier to deflate on OOM - VIRTIO_BALLOON_F_DEFLATE_ON_OOM */ + struct notifier_block oom_nb; + + /* Free page reporting device */ + struct virtqueue *reporting_vq; + struct page_reporting_dev_info pr_dev_info; + + /* State for keeping the wakeup_source active while adjusting the balloon */ + spinlock_t wakeup_lock; + bool processing_wakeup_event; + u32 wakeup_signal_mask; }; -static struct virtio_device_id id_table[] = { +#define VIRTIO_BALLOON_WAKEUP_SIGNAL_ADJUST (1 << 0) +#define VIRTIO_BALLOON_WAKEUP_SIGNAL_STATS (1 << 1) + +static const struct virtio_device_id id_table[] = { { VIRTIO_ID_BALLOON, VIRTIO_DEV_ANY_ID }, { 0 }, }; @@ -87,10 +143,34 @@ static u32 page_to_balloon_pfn(struct page *page) return pfn * VIRTIO_BALLOON_PAGES_PER_PAGE; } -static struct page *balloon_pfn_to_page(u32 pfn) +static void start_wakeup_event(struct virtio_balloon *vb, u32 mask) { - BUG_ON(pfn % VIRTIO_BALLOON_PAGES_PER_PAGE); - return pfn_to_page(pfn / VIRTIO_BALLOON_PAGES_PER_PAGE); + unsigned long flags; + + spin_lock_irqsave(&vb->wakeup_lock, flags); + vb->wakeup_signal_mask |= mask; + if (!vb->processing_wakeup_event) { + vb->processing_wakeup_event = true; + pm_stay_awake(&vb->vdev->dev); + } + spin_unlock_irqrestore(&vb->wakeup_lock, flags); +} + +static void process_wakeup_event(struct virtio_balloon *vb, u32 mask) +{ + spin_lock_irq(&vb->wakeup_lock); + vb->wakeup_signal_mask &= ~mask; + spin_unlock_irq(&vb->wakeup_lock); +} + +static void finish_wakeup_event(struct virtio_balloon *vb) +{ + spin_lock_irq(&vb->wakeup_lock); + if (!vb->wakeup_signal_mask && vb->processing_wakeup_event) { + vb->processing_wakeup_event = false; + pm_relax(&vb->vdev->dev); + } + spin_unlock_irq(&vb->wakeup_lock); } static void balloon_ack(struct virtqueue *vq) @@ -108,35 +188,70 @@ static void tell_host(struct virtio_balloon *vb, struct virtqueue *vq) sg_init_one(&sg, vb->pfns, sizeof(vb->pfns[0]) * vb->num_pfns); /* We should always be able to add one buffer to an empty queue. */ - if (virtqueue_add_outbuf(vq, &sg, 1, vb, GFP_KERNEL) < 0) - BUG(); + virtqueue_add_outbuf(vq, &sg, 1, vb, GFP_KERNEL); virtqueue_kick(vq); /* When host has read buffer, this completes via balloon_ack */ wait_event(vb->acked, virtqueue_get_buf(vq, &len)); + } -static void set_page_pfns(u32 pfns[], struct page *page) +static int virtballoon_free_page_report(struct page_reporting_dev_info *pr_dev_info, + struct scatterlist *sg, unsigned int nents) +{ + struct virtio_balloon *vb = + container_of(pr_dev_info, struct virtio_balloon, pr_dev_info); + struct virtqueue *vq = vb->reporting_vq; + unsigned int unused, err; + + /* We should always be able to add these buffers to an empty queue. */ + err = virtqueue_add_inbuf(vq, sg, nents, vb, GFP_NOWAIT); + + /* + * In the extremely unlikely case that something has occurred and we + * are able to trigger an error we will simply display a warning + * and exit without actually processing the pages. + */ + if (WARN_ON_ONCE(err)) + return err; + + virtqueue_kick(vq); + + /* When host has read buffer, this completes via balloon_ack */ + wait_event(vb->acked, virtqueue_get_buf(vq, &unused)); + + return 0; +} + +static void set_page_pfns(struct virtio_balloon *vb, + __virtio32 pfns[], struct page *page) { unsigned int i; - /* Set balloon pfns pointing at this page. - * Note that the first pfn points at start of the page. */ + BUILD_BUG_ON(VIRTIO_BALLOON_PAGES_PER_PAGE > VIRTIO_BALLOON_ARRAY_PFNS_MAX); + + /* + * Set balloon pfns pointing at this page. + * Note that the first pfn points at start of the page. + */ for (i = 0; i < VIRTIO_BALLOON_PAGES_PER_PAGE; i++) - pfns[i] = page_to_balloon_pfn(page) + i; + pfns[i] = cpu_to_virtio32(vb->vdev, + page_to_balloon_pfn(page) + i); } -static void fill_balloon(struct virtio_balloon *vb, size_t num) +static unsigned int fill_balloon(struct virtio_balloon *vb, size_t num) { - struct balloon_dev_info *vb_dev_info = vb->vb_dev_info; + unsigned int num_allocated_pages; + unsigned int num_pfns; + struct page *page; + LIST_HEAD(pages); /* We can only do one array worth at a time. */ num = min(num, ARRAY_SIZE(vb->pfns)); - mutex_lock(&vb->balloon_lock); - for (vb->num_pfns = 0; vb->num_pfns < num; - vb->num_pfns += VIRTIO_BALLOON_PAGES_PER_PAGE) { - struct page *page = balloon_page_enqueue(vb_dev_info); + for (num_pfns = 0; num_pfns < num; + num_pfns += VIRTIO_BALLOON_PAGES_PER_PAGE) { + page = balloon_page_alloc(); if (!page) { dev_info_ratelimited(&vb->vdev->dev, @@ -146,47 +261,72 @@ static void fill_balloon(struct virtio_balloon *vb, size_t num) msleep(200); break; } - set_page_pfns(vb->pfns + vb->num_pfns, page); + + balloon_page_push(&pages, page); + } + + mutex_lock(&vb->balloon_lock); + + vb->num_pfns = 0; + + while ((page = balloon_page_pop(&pages))) { + balloon_page_enqueue(&vb->vb_dev_info, page); + + set_page_pfns(vb, vb->pfns + vb->num_pfns, page); vb->num_pages += VIRTIO_BALLOON_PAGES_PER_PAGE; - adjust_managed_page_count(page, -1); + if (!virtio_has_feature(vb->vdev, + VIRTIO_BALLOON_F_DEFLATE_ON_OOM)) + adjust_managed_page_count(page, -1); + vb->num_pfns += VIRTIO_BALLOON_PAGES_PER_PAGE; } + num_allocated_pages = vb->num_pfns; /* Did we get any? */ if (vb->num_pfns != 0) tell_host(vb, vb->inflate_vq); mutex_unlock(&vb->balloon_lock); + + return num_allocated_pages; } -static void release_pages_by_pfn(const u32 pfns[], unsigned int num) +static void release_pages_balloon(struct virtio_balloon *vb, + struct list_head *pages) { - unsigned int i; - - /* Find pfns pointing at start of each page, get pages and free them. */ - for (i = 0; i < num; i += VIRTIO_BALLOON_PAGES_PER_PAGE) { - struct page *page = balloon_pfn_to_page(pfns[i]); - balloon_page_free(page); - adjust_managed_page_count(page, 1); + struct page *page, *next; + + list_for_each_entry_safe(page, next, pages, lru) { + if (!virtio_has_feature(vb->vdev, + VIRTIO_BALLOON_F_DEFLATE_ON_OOM)) + adjust_managed_page_count(page, 1); + list_del(&page->lru); + put_page(page); /* balloon reference */ } } -static void leak_balloon(struct virtio_balloon *vb, size_t num) +static unsigned int leak_balloon(struct virtio_balloon *vb, size_t num) { + unsigned int num_freed_pages; struct page *page; - struct balloon_dev_info *vb_dev_info = vb->vb_dev_info; + struct balloon_dev_info *vb_dev_info = &vb->vb_dev_info; + LIST_HEAD(pages); /* We can only do one array worth at a time. */ num = min(num, ARRAY_SIZE(vb->pfns)); mutex_lock(&vb->balloon_lock); + /* We can't release more pages than taken */ + num = min(num, (size_t)vb->num_pages); for (vb->num_pfns = 0; vb->num_pfns < num; vb->num_pfns += VIRTIO_BALLOON_PAGES_PER_PAGE) { page = balloon_page_dequeue(vb_dev_info); if (!page) break; - set_page_pfns(vb->pfns + vb->num_pfns, page); + set_page_pfns(vb, vb->pfns + vb->num_pfns, page); + list_add(&page->lru, &pages); vb->num_pages -= VIRTIO_BALLOON_PAGES_PER_PAGE; } + num_freed_pages = vb->num_pfns; /* * Note that if * virtio_has_feature(vdev, VIRTIO_BALLOON_F_MUST_TELL_HOST); @@ -194,39 +334,92 @@ static void leak_balloon(struct virtio_balloon *vb, size_t num) */ if (vb->num_pfns != 0) tell_host(vb, vb->deflate_vq); + release_pages_balloon(vb, &pages); mutex_unlock(&vb->balloon_lock); - release_pages_by_pfn(vb->pfns, vb->num_pfns); + return num_freed_pages; } static inline void update_stat(struct virtio_balloon *vb, int idx, u16 tag, u64 val) { BUG_ON(idx >= VIRTIO_BALLOON_S_NR); - vb->stats[idx].tag = tag; - vb->stats[idx].val = val; + vb->stats[idx].tag = cpu_to_virtio16(vb->vdev, tag); + vb->stats[idx].val = cpu_to_virtio64(vb->vdev, val); } #define pages_to_bytes(x) ((u64)(x) << PAGE_SHIFT) -static void update_balloon_stats(struct virtio_balloon *vb) +#ifdef CONFIG_VM_EVENT_COUNTERS +/* Return the number of entries filled by vm events */ +static inline unsigned int update_balloon_vm_stats(struct virtio_balloon *vb) { unsigned long events[NR_VM_EVENT_ITEMS]; - struct sysinfo i; - int idx = 0; + unsigned int idx = 0; + unsigned int zid; + unsigned long stall = 0; all_vm_events(events); - si_meminfo(&i); - update_stat(vb, idx++, VIRTIO_BALLOON_S_SWAP_IN, - pages_to_bytes(events[PSWPIN])); + pages_to_bytes(events[PSWPIN])); update_stat(vb, idx++, VIRTIO_BALLOON_S_SWAP_OUT, - pages_to_bytes(events[PSWPOUT])); + pages_to_bytes(events[PSWPOUT])); update_stat(vb, idx++, VIRTIO_BALLOON_S_MAJFLT, events[PGMAJFAULT]); update_stat(vb, idx++, VIRTIO_BALLOON_S_MINFLT, events[PGFAULT]); + update_stat(vb, idx++, VIRTIO_BALLOON_S_OOM_KILL, events[OOM_KILL]); + + /* sum all the stall events */ + for (zid = 0; zid < MAX_NR_ZONES; zid++) + stall += events[ALLOCSTALL_NORMAL - ZONE_NORMAL + zid]; + + update_stat(vb, idx++, VIRTIO_BALLOON_S_ALLOC_STALL, stall); + + update_stat(vb, idx++, VIRTIO_BALLOON_S_ASYNC_SCAN, + pages_to_bytes(events[PGSCAN_KSWAPD])); + update_stat(vb, idx++, VIRTIO_BALLOON_S_DIRECT_SCAN, + pages_to_bytes(events[PGSCAN_DIRECT])); + update_stat(vb, idx++, VIRTIO_BALLOON_S_ASYNC_RECLAIM, + pages_to_bytes(events[PGSTEAL_KSWAPD])); + update_stat(vb, idx++, VIRTIO_BALLOON_S_DIRECT_RECLAIM, + pages_to_bytes(events[PGSTEAL_DIRECT])); + +#ifdef CONFIG_HUGETLB_PAGE + update_stat(vb, idx++, VIRTIO_BALLOON_S_HTLB_PGALLOC, + events[HTLB_BUDDY_PGALLOC]); + update_stat(vb, idx++, VIRTIO_BALLOON_S_HTLB_PGFAIL, + events[HTLB_BUDDY_PGALLOC_FAIL]); +#endif /* CONFIG_HUGETLB_PAGE */ + + return idx; +} +#else /* CONFIG_VM_EVENT_COUNTERS */ +static inline unsigned int update_balloon_vm_stats(struct virtio_balloon *vb) +{ + return 0; +} +#endif /* CONFIG_VM_EVENT_COUNTERS */ + +static unsigned int update_balloon_stats(struct virtio_balloon *vb) +{ + struct sysinfo i; + unsigned int idx; + long available; + unsigned long caches; + + idx = update_balloon_vm_stats(vb); + + si_meminfo(&i); + available = si_mem_available(); + caches = global_node_page_state(NR_FILE_PAGES); update_stat(vb, idx++, VIRTIO_BALLOON_S_MEMFREE, pages_to_bytes(i.freeram)); update_stat(vb, idx++, VIRTIO_BALLOON_S_MEMTOT, pages_to_bytes(i.totalram)); + update_stat(vb, idx++, VIRTIO_BALLOON_S_AVAIL, + pages_to_bytes(available)); + update_stat(vb, idx++, VIRTIO_BALLOON_S_CACHES, + pages_to_bytes(caches)); + + return idx; } /* @@ -235,128 +428,386 @@ static void update_balloon_stats(struct virtio_balloon *vb) * with a single buffer. From that point forward, all conversations consist of * a hypervisor request (a call to this function) which directs us to refill * the virtqueue with a fresh stats buffer. Since stats collection can sleep, - * we notify our kthread which does the actual work via stats_handle_request(). + * we delegate the job to a freezable workqueue that will do the actual work via + * stats_handle_request(). */ static void stats_request(struct virtqueue *vq) { struct virtio_balloon *vb = vq->vdev->priv; - vb->need_stats_update = 1; - wake_up(&vb->config_change); + spin_lock(&vb->stop_update_lock); + if (!vb->stop_update) { + start_wakeup_event(vb, VIRTIO_BALLOON_WAKEUP_SIGNAL_STATS); + queue_work(system_freezable_wq, &vb->update_balloon_stats_work); + } + spin_unlock(&vb->stop_update_lock); } static void stats_handle_request(struct virtio_balloon *vb) { struct virtqueue *vq; struct scatterlist sg; - unsigned int len; + unsigned int len, num_stats; - vb->need_stats_update = 0; - update_balloon_stats(vb); + num_stats = update_balloon_stats(vb); vq = vb->stats_vq; if (!virtqueue_get_buf(vq, &len)) return; - sg_init_one(&sg, vb->stats, sizeof(vb->stats)); - if (virtqueue_add_outbuf(vq, &sg, 1, vb, GFP_KERNEL) < 0) - BUG(); + sg_init_one(&sg, vb->stats, sizeof(vb->stats[0]) * num_stats); + virtqueue_add_outbuf(vq, &sg, 1, vb, GFP_KERNEL); virtqueue_kick(vq); } +static inline s64 towards_target(struct virtio_balloon *vb) +{ + s64 target; + u32 num_pages; + + /* Legacy balloon config space is LE, unlike all other devices. */ + virtio_cread_le(vb->vdev, struct virtio_balloon_config, num_pages, + &num_pages); + + /* + * Aligned up to guest page size to avoid inflating and deflating + * balloon endlessly. + */ + target = ALIGN(num_pages, VIRTIO_BALLOON_PAGES_PER_PAGE); + return target - vb->num_pages; +} + +/* Gives back @num_to_return blocks of free pages to mm. */ +static unsigned long return_free_pages_to_mm(struct virtio_balloon *vb, + unsigned long num_to_return) +{ + struct page *page; + unsigned long num_returned; + + spin_lock_irq(&vb->free_page_list_lock); + for (num_returned = 0; num_returned < num_to_return; num_returned++) { + page = balloon_page_pop(&vb->free_page_list); + if (!page) + break; + __free_pages(page, VIRTIO_BALLOON_HINT_BLOCK_ORDER); + } + vb->num_free_page_blocks -= num_returned; + spin_unlock_irq(&vb->free_page_list_lock); + + return num_returned; +} + +static void virtio_balloon_queue_free_page_work(struct virtio_balloon *vb) +{ + if (!virtio_has_feature(vb->vdev, VIRTIO_BALLOON_F_FREE_PAGE_HINT)) + return; + + /* No need to queue the work if the bit was already set. */ + if (test_and_set_bit(VIRTIO_BALLOON_CONFIG_READ_CMD_ID, + &vb->config_read_bitmap)) + return; + + queue_work(vb->balloon_wq, &vb->report_free_page_work); +} + +static void start_update_balloon_size(struct virtio_balloon *vb) +{ + start_wakeup_event(vb, VIRTIO_BALLOON_WAKEUP_SIGNAL_ADJUST); + queue_work(system_freezable_wq, &vb->update_balloon_size_work); +} + static void virtballoon_changed(struct virtio_device *vdev) { struct virtio_balloon *vb = vdev->priv; + unsigned long flags; - wake_up(&vb->config_change); + spin_lock_irqsave(&vb->stop_update_lock, flags); + if (!vb->stop_update) { + start_update_balloon_size(vb); + virtio_balloon_queue_free_page_work(vb); + } + spin_unlock_irqrestore(&vb->stop_update_lock, flags); } -static inline s64 towards_target(struct virtio_balloon *vb) +static void update_balloon_size(struct virtio_balloon *vb) { - __le32 v; - s64 target; + u32 actual = vb->num_pages; - vb->vdev->config->get(vb->vdev, - offsetof(struct virtio_balloon_config, num_pages), - &v, sizeof(v)); - target = le32_to_cpu(v); - return target - vb->num_pages; + /* Legacy balloon config space is LE, unlike all other devices. */ + virtio_cwrite_le(vb->vdev, struct virtio_balloon_config, actual, + &actual); } -static void update_balloon_size(struct virtio_balloon *vb) +static void update_balloon_stats_func(struct work_struct *work) { - __le32 actual = cpu_to_le32(vb->num_pages); + struct virtio_balloon *vb; + + vb = container_of(work, struct virtio_balloon, + update_balloon_stats_work); - vb->vdev->config->set(vb->vdev, - offsetof(struct virtio_balloon_config, actual), - &actual, sizeof(actual)); + process_wakeup_event(vb, VIRTIO_BALLOON_WAKEUP_SIGNAL_STATS); + stats_handle_request(vb); + finish_wakeup_event(vb); } -static int balloon(void *_vballoon) +static void update_balloon_size_func(struct work_struct *work) { - struct virtio_balloon *vb = _vballoon; + struct virtio_balloon *vb; + s64 diff; + + vb = container_of(work, struct virtio_balloon, + update_balloon_size_work); - set_freezable(); - while (!kthread_should_stop()) { - s64 diff; + process_wakeup_event(vb, VIRTIO_BALLOON_WAKEUP_SIGNAL_ADJUST); - try_to_freeze(); - wait_event_interruptible(vb->config_change, - (diff = towards_target(vb)) != 0 - || vb->need_stats_update - || kthread_should_stop() - || freezing(current)); - if (vb->need_stats_update) - stats_handle_request(vb); + diff = towards_target(vb); + + if (diff) { if (diff > 0) - fill_balloon(vb, diff); - else if (diff < 0) - leak_balloon(vb, -diff); + diff -= fill_balloon(vb, diff); + else + diff += leak_balloon(vb, -diff); update_balloon_size(vb); } - return 0; + + if (diff) + queue_work(system_freezable_wq, work); + else + finish_wakeup_event(vb); } static int init_vqs(struct virtio_balloon *vb) { - struct virtqueue *vqs[3]; - vq_callback_t *callbacks[] = { balloon_ack, balloon_ack, stats_request }; - const char *names[] = { "inflate", "deflate", "stats" }; - int err, nvqs; + struct virtqueue_info vqs_info[VIRTIO_BALLOON_VQ_MAX] = {}; + struct virtqueue *vqs[VIRTIO_BALLOON_VQ_MAX]; + int err; /* - * We expect two virtqueues: inflate and deflate, and - * optionally stat. + * Inflateq and deflateq are used unconditionally. The names[] + * will be NULL if the related feature is not enabled, which will + * cause no allocation for the corresponding virtqueue in find_vqs. */ - nvqs = virtio_has_feature(vb->vdev, VIRTIO_BALLOON_F_STATS_VQ) ? 3 : 2; - err = vb->vdev->config->find_vqs(vb->vdev, nvqs, vqs, callbacks, names); + vqs_info[VIRTIO_BALLOON_VQ_INFLATE].callback = balloon_ack; + vqs_info[VIRTIO_BALLOON_VQ_INFLATE].name = "inflate"; + vqs_info[VIRTIO_BALLOON_VQ_DEFLATE].callback = balloon_ack; + vqs_info[VIRTIO_BALLOON_VQ_DEFLATE].name = "deflate"; + + if (virtio_has_feature(vb->vdev, VIRTIO_BALLOON_F_STATS_VQ)) { + vqs_info[VIRTIO_BALLOON_VQ_STATS].name = "stats"; + vqs_info[VIRTIO_BALLOON_VQ_STATS].callback = stats_request; + } + + if (virtio_has_feature(vb->vdev, VIRTIO_BALLOON_F_FREE_PAGE_HINT)) + vqs_info[VIRTIO_BALLOON_VQ_FREE_PAGE].name = "free_page_vq"; + + if (virtio_has_feature(vb->vdev, VIRTIO_BALLOON_F_REPORTING)) { + vqs_info[VIRTIO_BALLOON_VQ_REPORTING].name = "reporting_vq"; + vqs_info[VIRTIO_BALLOON_VQ_REPORTING].callback = balloon_ack; + } + + err = virtio_find_vqs(vb->vdev, VIRTIO_BALLOON_VQ_MAX, vqs, + vqs_info, NULL); if (err) return err; - vb->inflate_vq = vqs[0]; - vb->deflate_vq = vqs[1]; + vb->inflate_vq = vqs[VIRTIO_BALLOON_VQ_INFLATE]; + vb->deflate_vq = vqs[VIRTIO_BALLOON_VQ_DEFLATE]; if (virtio_has_feature(vb->vdev, VIRTIO_BALLOON_F_STATS_VQ)) { struct scatterlist sg; - vb->stats_vq = vqs[2]; + unsigned int num_stats; + vb->stats_vq = vqs[VIRTIO_BALLOON_VQ_STATS]; /* * Prime this virtqueue with one buffer so the hypervisor can - * use it to signal us later. + * use it to signal us later (it can't be broken yet!). */ - sg_init_one(&sg, vb->stats, sizeof vb->stats); - if (virtqueue_add_outbuf(vb->stats_vq, &sg, 1, vb, GFP_KERNEL) - < 0) - BUG(); + num_stats = update_balloon_stats(vb); + + sg_init_one(&sg, vb->stats, sizeof(vb->stats[0]) * num_stats); + err = virtqueue_add_outbuf(vb->stats_vq, &sg, 1, vb, + GFP_KERNEL); + if (err) { + dev_warn(&vb->vdev->dev, "%s: add stat_vq failed\n", + __func__); + return err; + } virtqueue_kick(vb->stats_vq); } + + if (virtio_has_feature(vb->vdev, VIRTIO_BALLOON_F_FREE_PAGE_HINT)) + vb->free_page_vq = vqs[VIRTIO_BALLOON_VQ_FREE_PAGE]; + + if (virtio_has_feature(vb->vdev, VIRTIO_BALLOON_F_REPORTING)) + vb->reporting_vq = vqs[VIRTIO_BALLOON_VQ_REPORTING]; + + return 0; +} + +static u32 virtio_balloon_cmd_id_received(struct virtio_balloon *vb) +{ + if (test_and_clear_bit(VIRTIO_BALLOON_CONFIG_READ_CMD_ID, + &vb->config_read_bitmap)) { + /* Legacy balloon config space is LE, unlike all other devices. */ + virtio_cread_le(vb->vdev, struct virtio_balloon_config, + free_page_hint_cmd_id, + &vb->cmd_id_received_cache); + } + + return vb->cmd_id_received_cache; +} + +static int send_cmd_id_start(struct virtio_balloon *vb) +{ + struct scatterlist sg; + struct virtqueue *vq = vb->free_page_vq; + int err, unused; + + /* Detach all the used buffers from the vq */ + while (virtqueue_get_buf(vq, &unused)) + ; + + vb->cmd_id_active = cpu_to_virtio32(vb->vdev, + virtio_balloon_cmd_id_received(vb)); + sg_init_one(&sg, &vb->cmd_id_active, sizeof(vb->cmd_id_active)); + err = virtqueue_add_outbuf(vq, &sg, 1, &vb->cmd_id_active, GFP_KERNEL); + if (!err) + virtqueue_kick(vq); + return err; +} + +static int send_cmd_id_stop(struct virtio_balloon *vb) +{ + struct scatterlist sg; + struct virtqueue *vq = vb->free_page_vq; + int err, unused; + + /* Detach all the used buffers from the vq */ + while (virtqueue_get_buf(vq, &unused)) + ; + + sg_init_one(&sg, &vb->cmd_id_stop, sizeof(vb->cmd_id_stop)); + err = virtqueue_add_outbuf(vq, &sg, 1, &vb->cmd_id_stop, GFP_KERNEL); + if (!err) + virtqueue_kick(vq); + return err; +} + +static int get_free_page_and_send(struct virtio_balloon *vb) +{ + struct virtqueue *vq = vb->free_page_vq; + struct page *page; + struct scatterlist sg; + int err, unused; + void *p; + + /* Detach all the used buffers from the vq */ + while (virtqueue_get_buf(vq, &unused)) + ; + + page = alloc_pages(VIRTIO_BALLOON_FREE_PAGE_ALLOC_FLAG, + VIRTIO_BALLOON_HINT_BLOCK_ORDER); + /* + * When the allocation returns NULL, it indicates that we have got all + * the possible free pages, so return -EINTR to stop. + */ + if (!page) + return -EINTR; + + p = page_address(page); + sg_init_one(&sg, p, VIRTIO_BALLOON_HINT_BLOCK_BYTES); + /* There is always 1 entry reserved for the cmd id to use. */ + if (vq->num_free > 1) { + err = virtqueue_add_inbuf(vq, &sg, 1, p, GFP_KERNEL); + if (unlikely(err)) { + __free_pages(page, VIRTIO_BALLOON_HINT_BLOCK_ORDER); + return err; + } + virtqueue_kick(vq); + spin_lock_irq(&vb->free_page_list_lock); + balloon_page_push(&vb->free_page_list, page); + vb->num_free_page_blocks++; + spin_unlock_irq(&vb->free_page_list_lock); + } else { + /* + * The vq has no available entry to add this page block, so + * just free it. + */ + __free_pages(page, VIRTIO_BALLOON_HINT_BLOCK_ORDER); + } + return 0; } -static const struct address_space_operations virtio_balloon_aops; +static int send_free_pages(struct virtio_balloon *vb) +{ + int err; + u32 cmd_id_active; + + while (1) { + /* + * If a stop id or a new cmd id was just received from host, + * stop the reporting. + */ + cmd_id_active = virtio32_to_cpu(vb->vdev, vb->cmd_id_active); + if (unlikely(cmd_id_active != + virtio_balloon_cmd_id_received(vb))) + break; + + /* + * The free page blocks are allocated and sent to host one by + * one. + */ + err = get_free_page_and_send(vb); + if (err == -EINTR) + break; + else if (unlikely(err)) + return err; + } + + return 0; +} + +static void virtio_balloon_report_free_page(struct virtio_balloon *vb) +{ + int err; + struct device *dev = &vb->vdev->dev; + + /* Start by sending the received cmd id to host with an outbuf. */ + err = send_cmd_id_start(vb); + if (unlikely(err)) + dev_err(dev, "Failed to send a start id, err = %d\n", err); + + err = send_free_pages(vb); + if (unlikely(err)) + dev_err(dev, "Failed to send a free page, err = %d\n", err); + + /* End by sending a stop id to host with an outbuf. */ + err = send_cmd_id_stop(vb); + if (unlikely(err)) + dev_err(dev, "Failed to send a stop id, err = %d\n", err); +} + +static void report_free_page_func(struct work_struct *work) +{ + struct virtio_balloon *vb = container_of(work, struct virtio_balloon, + report_free_page_work); + u32 cmd_id_received; + + cmd_id_received = virtio_balloon_cmd_id_received(vb); + if (cmd_id_received == VIRTIO_BALLOON_CMD_ID_DONE) { + /* Pass ULONG_MAX to give back all the free pages */ + return_free_pages_to_mm(vb, ULONG_MAX); + } else if (cmd_id_received != VIRTIO_BALLOON_CMD_ID_STOP && + cmd_id_received != + virtio32_to_cpu(vb->vdev, vb->cmd_id_active)) { + virtio_balloon_report_free_page(vb); + } +} + #ifdef CONFIG_BALLOON_COMPACTION /* * virtballoon_migratepage - perform the balloon page migration on behalf of - * a compation thread. (called under page lock) - * @mapping: the page->mapping which will be assigned to the new migrated page. + * a compaction thread. (called under page lock) + * @vb_dev_info: the balloon device * @newpage: page that will replace the isolated page after migration finishes. * @page : the isolated (old) page that is about to be migrated to newpage. * @mode : compaction mode -- not used for balloon page migration. @@ -369,19 +820,15 @@ static const struct address_space_operations virtio_balloon_aops; * 2) update the host about the old page removed from vb->pages list; * * This function preforms the balloon page migration task. - * Called through balloon_mapping->a_ops->migratepage + * Called through movable_operations->migrate_page */ -int virtballoon_migratepage(struct address_space *mapping, +static int virtballoon_migratepage(struct balloon_dev_info *vb_dev_info, struct page *newpage, struct page *page, enum migrate_mode mode) { - struct balloon_dev_info *vb_dev_info = balloon_page_device(page); - struct virtio_balloon *vb; + struct virtio_balloon *vb = container_of(vb_dev_info, + struct virtio_balloon, vb_dev_info); unsigned long flags; - BUG_ON(!vb_dev_info); - - vb = vb_dev_info->balloon_device; - /* * In order to avoid lock contention while migrating pages concurrently * to leak_balloon() or fill_balloon() we just give up the balloon_lock @@ -393,96 +840,260 @@ int virtballoon_migratepage(struct address_space *mapping, if (!mutex_trylock(&vb->balloon_lock)) return -EAGAIN; + get_page(newpage); /* balloon reference */ + + /* + * When we migrate a page to a different zone and adjusted the + * managed page count when inflating, we have to fixup the count of + * both involved zones. + */ + if (!virtio_has_feature(vb->vdev, VIRTIO_BALLOON_F_DEFLATE_ON_OOM) && + page_zone(page) != page_zone(newpage)) { + adjust_managed_page_count(page, 1); + adjust_managed_page_count(newpage, -1); + } + /* balloon's page migration 1st step -- inflate "newpage" */ spin_lock_irqsave(&vb_dev_info->pages_lock, flags); - balloon_page_insert(newpage, mapping, &vb_dev_info->pages); + balloon_page_insert(vb_dev_info, newpage); vb_dev_info->isolated_pages--; + __count_vm_event(BALLOON_MIGRATE); spin_unlock_irqrestore(&vb_dev_info->pages_lock, flags); vb->num_pfns = VIRTIO_BALLOON_PAGES_PER_PAGE; - set_page_pfns(vb->pfns, newpage); + set_page_pfns(vb, vb->pfns, newpage); tell_host(vb, vb->inflate_vq); - /* - * balloon's page migration 2nd step -- deflate "page" - * - * It's safe to delete page->lru here because this page is at - * an isolated migration list, and this step is expected to happen here - */ - balloon_page_delete(page); + /* balloon's page migration 2nd step -- deflate "page" */ vb->num_pfns = VIRTIO_BALLOON_PAGES_PER_PAGE; - set_page_pfns(vb->pfns, page); + set_page_pfns(vb, vb->pfns, page); tell_host(vb, vb->deflate_vq); mutex_unlock(&vb->balloon_lock); - return MIGRATEPAGE_BALLOON_SUCCESS; -} + balloon_page_finalize(page); + put_page(page); /* balloon reference */ -/* define the balloon_mapping->a_ops callback to allow balloon page migration */ -static const struct address_space_operations virtio_balloon_aops = { - .migratepage = virtballoon_migratepage, -}; + return 0; +} #endif /* CONFIG_BALLOON_COMPACTION */ +static unsigned long shrink_free_pages(struct virtio_balloon *vb, + unsigned long pages_to_free) +{ + unsigned long blocks_to_free, blocks_freed; + + pages_to_free = round_up(pages_to_free, + VIRTIO_BALLOON_HINT_BLOCK_PAGES); + blocks_to_free = pages_to_free / VIRTIO_BALLOON_HINT_BLOCK_PAGES; + blocks_freed = return_free_pages_to_mm(vb, blocks_to_free); + + return blocks_freed * VIRTIO_BALLOON_HINT_BLOCK_PAGES; +} + +static unsigned long virtio_balloon_shrinker_scan(struct shrinker *shrinker, + struct shrink_control *sc) +{ + struct virtio_balloon *vb = shrinker->private_data; + + return shrink_free_pages(vb, sc->nr_to_scan); +} + +static unsigned long virtio_balloon_shrinker_count(struct shrinker *shrinker, + struct shrink_control *sc) +{ + struct virtio_balloon *vb = shrinker->private_data; + + return vb->num_free_page_blocks * VIRTIO_BALLOON_HINT_BLOCK_PAGES; +} + +static int virtio_balloon_oom_notify(struct notifier_block *nb, + unsigned long dummy, void *parm) +{ + struct virtio_balloon *vb = container_of(nb, + struct virtio_balloon, oom_nb); + unsigned long *freed = parm; + + *freed += leak_balloon(vb, VIRTIO_BALLOON_OOM_NR_PAGES) / + VIRTIO_BALLOON_PAGES_PER_PAGE; + update_balloon_size(vb); + + return NOTIFY_OK; +} + +static void virtio_balloon_unregister_shrinker(struct virtio_balloon *vb) +{ + shrinker_free(vb->shrinker); +} + +static int virtio_balloon_register_shrinker(struct virtio_balloon *vb) +{ + vb->shrinker = shrinker_alloc(0, "virtio-balloon"); + if (!vb->shrinker) + return -ENOMEM; + + vb->shrinker->scan_objects = virtio_balloon_shrinker_scan; + vb->shrinker->count_objects = virtio_balloon_shrinker_count; + vb->shrinker->private_data = vb; + + shrinker_register(vb->shrinker); + + return 0; +} + static int virtballoon_probe(struct virtio_device *vdev) { struct virtio_balloon *vb; - struct address_space *vb_mapping; - struct balloon_dev_info *vb_devinfo; int err; - vdev->priv = vb = kmalloc(sizeof(*vb), GFP_KERNEL); + if (!vdev->config->get) { + dev_err(&vdev->dev, "%s failure: config access disabled\n", + __func__); + return -EINVAL; + } + + vdev->priv = vb = kzalloc(sizeof(*vb), GFP_KERNEL); if (!vb) { err = -ENOMEM; goto out; } - vb->num_pages = 0; + INIT_WORK(&vb->update_balloon_stats_work, update_balloon_stats_func); + INIT_WORK(&vb->update_balloon_size_work, update_balloon_size_func); + spin_lock_init(&vb->stop_update_lock); mutex_init(&vb->balloon_lock); - init_waitqueue_head(&vb->config_change); init_waitqueue_head(&vb->acked); vb->vdev = vdev; - vb->need_stats_update = 0; - vb_devinfo = balloon_devinfo_alloc(vb); - if (IS_ERR(vb_devinfo)) { - err = PTR_ERR(vb_devinfo); + balloon_devinfo_init(&vb->vb_dev_info); + + err = init_vqs(vb); + if (err) goto out_free_vb; + +#ifdef CONFIG_BALLOON_COMPACTION + vb->vb_dev_info.migratepage = virtballoon_migratepage; +#endif + if (virtio_has_feature(vdev, VIRTIO_BALLOON_F_FREE_PAGE_HINT)) { + /* + * There is always one entry reserved for cmd id, so the ring + * size needs to be at least two to report free page hints. + */ + if (virtqueue_get_vring_size(vb->free_page_vq) < 2) { + err = -ENOSPC; + goto out_del_vqs; + } + vb->balloon_wq = alloc_workqueue("balloon-wq", + WQ_FREEZABLE | WQ_CPU_INTENSIVE | WQ_PERCPU, + 0); + if (!vb->balloon_wq) { + err = -ENOMEM; + goto out_del_vqs; + } + INIT_WORK(&vb->report_free_page_work, report_free_page_func); + vb->cmd_id_received_cache = VIRTIO_BALLOON_CMD_ID_STOP; + vb->cmd_id_active = cpu_to_virtio32(vb->vdev, + VIRTIO_BALLOON_CMD_ID_STOP); + vb->cmd_id_stop = cpu_to_virtio32(vb->vdev, + VIRTIO_BALLOON_CMD_ID_STOP); + spin_lock_init(&vb->free_page_list_lock); + INIT_LIST_HEAD(&vb->free_page_list); + /* + * We're allowed to reuse any free pages, even if they are + * still to be processed by the host. + */ + err = virtio_balloon_register_shrinker(vb); + if (err) + goto out_del_balloon_wq; + } + + if (virtio_has_feature(vb->vdev, VIRTIO_BALLOON_F_DEFLATE_ON_OOM)) { + vb->oom_nb.notifier_call = virtio_balloon_oom_notify; + vb->oom_nb.priority = VIRTIO_BALLOON_OOM_NOTIFY_PRIORITY; + err = register_oom_notifier(&vb->oom_nb); + if (err < 0) + goto out_unregister_shrinker; } - vb_mapping = balloon_mapping_alloc(vb_devinfo, - (balloon_compaction_check()) ? - &virtio_balloon_aops : NULL); - if (IS_ERR(vb_mapping)) { + if (virtio_has_feature(vdev, VIRTIO_BALLOON_F_PAGE_POISON)) { + /* Start with poison val of 0 representing general init */ + __u32 poison_val = 0; + /* - * IS_ERR(vb_mapping) && PTR_ERR(vb_mapping) == -EOPNOTSUPP - * This means !CONFIG_BALLOON_COMPACTION, otherwise we get off. + * Let the hypervisor know that we are expecting a + * specific value to be written back in balloon pages. + * + * If the PAGE_POISON value was larger than a byte we would + * need to byte swap poison_val here to guarantee it is + * little-endian. However for now it is a single byte so we + * can pass it as-is. */ - err = PTR_ERR(vb_mapping); - if (err != -EOPNOTSUPP) - goto out_free_vb_devinfo; + if (!want_init_on_free()) + memset(&poison_val, PAGE_POISON, sizeof(poison_val)); + + virtio_cwrite_le(vb->vdev, struct virtio_balloon_config, + poison_val, &poison_val); } - vb->vb_dev_info = vb_devinfo; + vb->pr_dev_info.report = virtballoon_free_page_report; + if (virtio_has_feature(vb->vdev, VIRTIO_BALLOON_F_REPORTING)) { + unsigned int capacity; - err = init_vqs(vb); - if (err) - goto out_free_vb_mapping; + capacity = virtqueue_get_vring_size(vb->reporting_vq); + if (capacity < PAGE_REPORTING_CAPACITY) { + err = -ENOSPC; + goto out_unregister_oom; + } + + /* + * The default page reporting order is @pageblock_order, which + * corresponds to 512MB in size on ARM64 when 64KB base page + * size is used. The page reporting won't be triggered if the + * freeing page can't come up with a free area like that huge. + * So we specify the page reporting order to 5, corresponding + * to 2MB. It helps to avoid THP splitting if 4KB base page + * size is used by host. + * + * Ideally, the page reporting order is selected based on the + * host's base page size. However, it needs more work to report + * that value. The hard-coded order would be fine currently. + */ +#if defined(CONFIG_ARM64) && defined(CONFIG_ARM64_64K_PAGES) + vb->pr_dev_info.order = 5; +#endif - vb->thread = kthread_run(balloon, vb, "vballoon"); - if (IS_ERR(vb->thread)) { - err = PTR_ERR(vb->thread); - goto out_del_vqs; + err = page_reporting_register(&vb->pr_dev_info); + if (err) + goto out_unregister_oom; } + spin_lock_init(&vb->wakeup_lock); + + /* + * The virtio balloon itself can't wake up the device, but it is + * responsible for processing wakeup events passed up from the transport + * layer. Wakeup sources don't support nesting/chaining calls, so we use + * our own wakeup source to ensure wakeup events are properly handled + * without trampling on the transport layer's wakeup source. + */ + device_set_wakeup_capable(&vb->vdev->dev, true); + + virtio_device_ready(vdev); + + if (towards_target(vb)) + virtballoon_changed(vdev); return 0; +out_unregister_oom: + if (virtio_has_feature(vb->vdev, VIRTIO_BALLOON_F_DEFLATE_ON_OOM)) + unregister_oom_notifier(&vb->oom_nb); +out_unregister_shrinker: + if (virtio_has_feature(vb->vdev, VIRTIO_BALLOON_F_FREE_PAGE_HINT)) + virtio_balloon_unregister_shrinker(vb); +out_del_balloon_wq: + if (virtio_has_feature(vdev, VIRTIO_BALLOON_F_FREE_PAGE_HINT)) + destroy_workqueue(vb->balloon_wq); out_del_vqs: vdev->config->del_vqs(vdev); -out_free_vb_mapping: - balloon_mapping_free(vb_mapping); -out_free_vb_devinfo: - balloon_devinfo_free(vb_devinfo); out_free_vb: kfree(vb); out: @@ -496,8 +1107,12 @@ static void remove_common(struct virtio_balloon *vb) leak_balloon(vb, vb->num_pages); update_balloon_size(vb); + /* There might be free pages that are being reported: release them. */ + if (virtio_has_feature(vb->vdev, VIRTIO_BALLOON_F_FREE_PAGE_HINT)) + return_free_pages_to_mm(vb, ULONG_MAX); + /* Now we reset the device so we can clean up the queues. */ - vb->vdev->config->reset(vb->vdev); + virtio_reset_device(vb->vdev); vb->vdev->config->del_vqs(vb->vdev); } @@ -506,23 +1121,36 @@ static void virtballoon_remove(struct virtio_device *vdev) { struct virtio_balloon *vb = vdev->priv; - kthread_stop(vb->thread); + if (virtio_has_feature(vb->vdev, VIRTIO_BALLOON_F_REPORTING)) + page_reporting_unregister(&vb->pr_dev_info); + if (virtio_has_feature(vb->vdev, VIRTIO_BALLOON_F_DEFLATE_ON_OOM)) + unregister_oom_notifier(&vb->oom_nb); + if (virtio_has_feature(vb->vdev, VIRTIO_BALLOON_F_FREE_PAGE_HINT)) + virtio_balloon_unregister_shrinker(vb); + spin_lock_irq(&vb->stop_update_lock); + vb->stop_update = true; + spin_unlock_irq(&vb->stop_update_lock); + cancel_work_sync(&vb->update_balloon_size_work); + cancel_work_sync(&vb->update_balloon_stats_work); + + if (virtio_has_feature(vdev, VIRTIO_BALLOON_F_FREE_PAGE_HINT)) { + cancel_work_sync(&vb->report_free_page_work); + destroy_workqueue(vb->balloon_wq); + } + remove_common(vb); - balloon_mapping_free(vb->vb_dev_info->mapping); - balloon_devinfo_free(vb->vb_dev_info); kfree(vb); } -#ifdef CONFIG_PM +#ifdef CONFIG_PM_SLEEP static int virtballoon_freeze(struct virtio_device *vdev) { struct virtio_balloon *vb = vdev->priv; /* - * The kthread is already frozen by the PM core before this + * The workqueue is already frozen by the PM core before this * function is called. */ - remove_common(vb); return 0; } @@ -536,27 +1164,51 @@ static int virtballoon_restore(struct virtio_device *vdev) if (ret) return ret; - fill_balloon(vb, towards_target(vb)); + virtio_device_ready(vdev); + + if (towards_target(vb)) + virtballoon_changed(vdev); update_balloon_size(vb); return 0; } #endif +static int virtballoon_validate(struct virtio_device *vdev) +{ + /* + * Inform the hypervisor that our pages are poisoned or + * initialized. If we cannot do that then we should disable + * page reporting as it could potentially change the contents + * of our free pages. + */ + if (!want_init_on_free() && !page_poisoning_enabled_static()) + __virtio_clear_bit(vdev, VIRTIO_BALLOON_F_PAGE_POISON); + else if (!virtio_has_feature(vdev, VIRTIO_BALLOON_F_PAGE_POISON)) + __virtio_clear_bit(vdev, VIRTIO_BALLOON_F_REPORTING); + + __virtio_clear_bit(vdev, VIRTIO_F_ACCESS_PLATFORM); + return 0; +} + static unsigned int features[] = { VIRTIO_BALLOON_F_MUST_TELL_HOST, VIRTIO_BALLOON_F_STATS_VQ, + VIRTIO_BALLOON_F_DEFLATE_ON_OOM, + VIRTIO_BALLOON_F_FREE_PAGE_HINT, + VIRTIO_BALLOON_F_PAGE_POISON, + VIRTIO_BALLOON_F_REPORTING, }; static struct virtio_driver virtio_balloon_driver = { .feature_table = features, .feature_table_size = ARRAY_SIZE(features), .driver.name = KBUILD_MODNAME, - .driver.owner = THIS_MODULE, .id_table = id_table, + .validate = virtballoon_validate, .probe = virtballoon_probe, .remove = virtballoon_remove, .config_changed = virtballoon_changed, -#ifdef CONFIG_PM +#ifdef CONFIG_PM_SLEEP .freeze = virtballoon_freeze, .restore = virtballoon_restore, #endif diff --git a/drivers/virtio/virtio_debug.c b/drivers/virtio/virtio_debug.c new file mode 100644 index 000000000000..ccf1955a1183 --- /dev/null +++ b/drivers/virtio/virtio_debug.c @@ -0,0 +1,117 @@ +// SPDX-License-Identifier: GPL-2.0-or-later + +#include <linux/virtio.h> +#include <linux/virtio_config.h> +#include <linux/debugfs.h> + +static struct dentry *virtio_debugfs_dir; + +static int virtio_debug_device_features_show(struct seq_file *s, void *data) +{ + u64 device_features[VIRTIO_FEATURES_U64S]; + struct virtio_device *dev = s->private; + unsigned int i; + + virtio_get_features(dev, device_features); + for (i = 0; i < VIRTIO_FEATURES_BITS; i++) { + if (virtio_features_test_bit(device_features, i)) + seq_printf(s, "%u\n", i); + } + return 0; +} +DEFINE_SHOW_ATTRIBUTE(virtio_debug_device_features); + +static int virtio_debug_filter_features_show(struct seq_file *s, void *data) +{ + struct virtio_device *dev = s->private; + unsigned int i; + + for (i = 0; i < VIRTIO_FEATURES_BITS; i++) { + if (virtio_features_test_bit(dev->debugfs_filter_features, i)) + seq_printf(s, "%u\n", i); + } + return 0; +} +DEFINE_SHOW_ATTRIBUTE(virtio_debug_filter_features); + +static int virtio_debug_filter_features_clear(void *data, u64 val) +{ + struct virtio_device *dev = data; + + if (val == 1) + virtio_features_zero(dev->debugfs_filter_features); + return 0; +} + +DEFINE_DEBUGFS_ATTRIBUTE(virtio_debug_filter_features_clear_fops, NULL, + virtio_debug_filter_features_clear, "%llu\n"); + +static int virtio_debug_filter_feature_add(void *data, u64 val) +{ + struct virtio_device *dev = data; + + if (val >= VIRTIO_FEATURES_BITS) + return -EINVAL; + + virtio_features_set_bit(dev->debugfs_filter_features, val); + return 0; +} + +DEFINE_DEBUGFS_ATTRIBUTE(virtio_debug_filter_feature_add_fops, NULL, + virtio_debug_filter_feature_add, "%llu\n"); + +static int virtio_debug_filter_feature_del(void *data, u64 val) +{ + struct virtio_device *dev = data; + + if (val >= VIRTIO_FEATURES_BITS) + return -EINVAL; + + virtio_features_clear_bit(dev->debugfs_filter_features, val); + return 0; +} + +DEFINE_DEBUGFS_ATTRIBUTE(virtio_debug_filter_feature_del_fops, NULL, + virtio_debug_filter_feature_del, "%llu\n"); + +void virtio_debug_device_init(struct virtio_device *dev) +{ + dev->debugfs_dir = debugfs_create_dir(dev_name(&dev->dev), + virtio_debugfs_dir); + debugfs_create_file("device_features", 0400, dev->debugfs_dir, dev, + &virtio_debug_device_features_fops); + debugfs_create_file("filter_features", 0400, dev->debugfs_dir, dev, + &virtio_debug_filter_features_fops); + debugfs_create_file("filter_features_clear", 0200, dev->debugfs_dir, dev, + &virtio_debug_filter_features_clear_fops); + debugfs_create_file("filter_feature_add", 0200, dev->debugfs_dir, dev, + &virtio_debug_filter_feature_add_fops); + debugfs_create_file("filter_feature_del", 0200, dev->debugfs_dir, dev, + &virtio_debug_filter_feature_del_fops); +} +EXPORT_SYMBOL_GPL(virtio_debug_device_init); + +void virtio_debug_device_filter_features(struct virtio_device *dev) +{ + virtio_features_andnot(dev->features_array, dev->features_array, + dev->debugfs_filter_features); +} +EXPORT_SYMBOL_GPL(virtio_debug_device_filter_features); + +void virtio_debug_device_exit(struct virtio_device *dev) +{ + debugfs_remove_recursive(dev->debugfs_dir); +} +EXPORT_SYMBOL_GPL(virtio_debug_device_exit); + +void virtio_debug_init(void) +{ + virtio_debugfs_dir = debugfs_create_dir("virtio", NULL); +} +EXPORT_SYMBOL_GPL(virtio_debug_init); + +void virtio_debug_exit(void) +{ + debugfs_remove_recursive(virtio_debugfs_dir); +} +EXPORT_SYMBOL_GPL(virtio_debug_exit); diff --git a/drivers/virtio/virtio_dma_buf.c b/drivers/virtio/virtio_dma_buf.c new file mode 100644 index 000000000000..95c10632f84a --- /dev/null +++ b/drivers/virtio/virtio_dma_buf.c @@ -0,0 +1,92 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * dma-bufs for virtio exported objects + * + * Copyright (C) 2020 Google, Inc. + */ + +#include <linux/module.h> +#include <linux/virtio_dma_buf.h> + +/** + * virtio_dma_buf_export - Creates a new dma-buf for a virtio exported object + * @exp_info: [in] see dma_buf_export(). ops MUST refer to a dma_buf_ops + * struct embedded in a virtio_dma_buf_ops. + * + * This wraps dma_buf_export() to allow virtio drivers to create a dma-buf + * for an virtio exported object that can be queried by other virtio drivers + * for the object's UUID. + */ +struct dma_buf *virtio_dma_buf_export + (const struct dma_buf_export_info *exp_info) +{ + const struct virtio_dma_buf_ops *virtio_ops = + container_of(exp_info->ops, + const struct virtio_dma_buf_ops, ops); + + if (!exp_info->ops || + exp_info->ops->attach != &virtio_dma_buf_attach || + !virtio_ops->get_uuid) { + return ERR_PTR(-EINVAL); + } + + return dma_buf_export(exp_info); +} +EXPORT_SYMBOL(virtio_dma_buf_export); + +/** + * virtio_dma_buf_attach - mandatory attach callback for virtio dma-bufs + * @dma_buf: [in] buffer to attach + * @attach: [in] attachment structure + */ +int virtio_dma_buf_attach(struct dma_buf *dma_buf, + struct dma_buf_attachment *attach) +{ + int ret; + const struct virtio_dma_buf_ops *ops = + container_of(dma_buf->ops, + const struct virtio_dma_buf_ops, ops); + + if (ops->device_attach) { + ret = ops->device_attach(dma_buf, attach); + if (ret) + return ret; + } + return 0; +} +EXPORT_SYMBOL(virtio_dma_buf_attach); + +/** + * is_virtio_dma_buf - returns true if the given dma-buf is a virtio dma-buf + * @dma_buf: buffer to query + */ +bool is_virtio_dma_buf(struct dma_buf *dma_buf) +{ + return dma_buf->ops->attach == &virtio_dma_buf_attach; +} +EXPORT_SYMBOL(is_virtio_dma_buf); + +/** + * virtio_dma_buf_get_uuid - gets a virtio dma-buf's exported object's uuid + * @dma_buf: [in] buffer to query + * @uuid: [out] the uuid + * + * Returns: 0 on success, negative on failure. + */ +int virtio_dma_buf_get_uuid(struct dma_buf *dma_buf, + uuid_t *uuid) +{ + const struct virtio_dma_buf_ops *ops = + container_of(dma_buf->ops, + const struct virtio_dma_buf_ops, ops); + + if (!is_virtio_dma_buf(dma_buf)) + return -EINVAL; + + return ops->get_uuid(dma_buf, uuid); +} +EXPORT_SYMBOL(virtio_dma_buf_get_uuid); + +MODULE_DESCRIPTION("dma-bufs for virtio exported objects"); +MODULE_LICENSE("GPL"); +MODULE_IMPORT_NS("DMA_BUF"); diff --git a/drivers/virtio/virtio_input.c b/drivers/virtio/virtio_input.c new file mode 100644 index 000000000000..d0728285b6ce --- /dev/null +++ b/drivers/virtio/virtio_input.c @@ -0,0 +1,418 @@ +// SPDX-License-Identifier: GPL-2.0-only +#include <linux/module.h> +#include <linux/virtio.h> +#include <linux/virtio_config.h> +#include <linux/input.h> +#include <linux/slab.h> + +#include <uapi/linux/virtio_ids.h> +#include <uapi/linux/virtio_input.h> +#include <linux/input/mt.h> + +struct virtio_input { + struct virtio_device *vdev; + struct input_dev *idev; + char name[64]; + char serial[64]; + char phys[64]; + struct virtqueue *evt, *sts; + struct virtio_input_event evts[64]; + spinlock_t lock; + bool ready; +}; + +static void virtinput_queue_evtbuf(struct virtio_input *vi, + struct virtio_input_event *evtbuf) +{ + struct scatterlist sg[1]; + + sg_init_one(sg, evtbuf, sizeof(*evtbuf)); + virtqueue_add_inbuf(vi->evt, sg, 1, evtbuf, GFP_ATOMIC); +} + +static void virtinput_recv_events(struct virtqueue *vq) +{ + struct virtio_input *vi = vq->vdev->priv; + struct virtio_input_event *event; + unsigned long flags; + unsigned int len; + + spin_lock_irqsave(&vi->lock, flags); + if (vi->ready) { + while ((event = virtqueue_get_buf(vi->evt, &len)) != NULL) { + spin_unlock_irqrestore(&vi->lock, flags); + input_event(vi->idev, + le16_to_cpu(event->type), + le16_to_cpu(event->code), + le32_to_cpu(event->value)); + spin_lock_irqsave(&vi->lock, flags); + virtinput_queue_evtbuf(vi, event); + } + virtqueue_kick(vq); + } + spin_unlock_irqrestore(&vi->lock, flags); +} + +/* + * On error we are losing the status update, which isn't critical as + * this is typically used for stuff like keyboard leds. + */ +static int virtinput_send_status(struct virtio_input *vi, + u16 type, u16 code, s32 value) +{ + struct virtio_input_event *stsbuf; + struct scatterlist sg[1]; + unsigned long flags; + int rc; + + /* + * Since 29cc309d8bf1 (HID: hid-multitouch: forward MSC_TIMESTAMP), + * EV_MSC/MSC_TIMESTAMP is added to each before EV_SYN event. + * EV_MSC is configured as INPUT_PASS_TO_ALL. + * In case of touch device: + * BE pass EV_MSC/MSC_TIMESTAMP to FE on receiving event from evdev. + * FE pass EV_MSC/MSC_TIMESTAMP back to BE. + * BE writes EV_MSC/MSC_TIMESTAMP to evdev due to INPUT_PASS_TO_ALL. + * BE receives extra EV_MSC/MSC_TIMESTAMP and pass to FE. + * >>> Each new frame becomes larger and larger. + * Disable EV_MSC/MSC_TIMESTAMP forwarding for MT. + */ + if (vi->idev->mt && type == EV_MSC && code == MSC_TIMESTAMP) + return 0; + + stsbuf = kzalloc(sizeof(*stsbuf), GFP_ATOMIC); + if (!stsbuf) + return -ENOMEM; + + stsbuf->type = cpu_to_le16(type); + stsbuf->code = cpu_to_le16(code); + stsbuf->value = cpu_to_le32(value); + sg_init_one(sg, stsbuf, sizeof(*stsbuf)); + + spin_lock_irqsave(&vi->lock, flags); + if (vi->ready) { + rc = virtqueue_add_outbuf(vi->sts, sg, 1, stsbuf, GFP_ATOMIC); + virtqueue_kick(vi->sts); + } else { + rc = -ENODEV; + } + spin_unlock_irqrestore(&vi->lock, flags); + + if (rc != 0) + kfree(stsbuf); + return rc; +} + +static void virtinput_recv_status(struct virtqueue *vq) +{ + struct virtio_input *vi = vq->vdev->priv; + struct virtio_input_event *stsbuf; + unsigned long flags; + unsigned int len; + + spin_lock_irqsave(&vi->lock, flags); + while ((stsbuf = virtqueue_get_buf(vi->sts, &len)) != NULL) + kfree(stsbuf); + spin_unlock_irqrestore(&vi->lock, flags); +} + +static int virtinput_status(struct input_dev *idev, unsigned int type, + unsigned int code, int value) +{ + struct virtio_input *vi = input_get_drvdata(idev); + + return virtinput_send_status(vi, type, code, value); +} + +static u8 virtinput_cfg_select(struct virtio_input *vi, + u8 select, u8 subsel) +{ + u8 size; + + virtio_cwrite_le(vi->vdev, struct virtio_input_config, select, &select); + virtio_cwrite_le(vi->vdev, struct virtio_input_config, subsel, &subsel); + virtio_cread_le(vi->vdev, struct virtio_input_config, size, &size); + return size; +} + +static void virtinput_cfg_bits(struct virtio_input *vi, int select, int subsel, + unsigned long *bits, unsigned int bitcount) +{ + unsigned int bit; + u8 *virtio_bits; + u8 bytes; + + bytes = virtinput_cfg_select(vi, select, subsel); + if (!bytes) + return; + if (bitcount > bytes * 8) + bitcount = bytes * 8; + + /* + * Bitmap in virtio config space is a simple stream of bytes, + * with the first byte carrying bits 0-7, second bits 8-15 and + * so on. + */ + virtio_bits = kzalloc(bytes, GFP_KERNEL); + if (!virtio_bits) + return; + virtio_cread_bytes(vi->vdev, offsetof(struct virtio_input_config, + u.bitmap), + virtio_bits, bytes); + for (bit = 0; bit < bitcount; bit++) { + if (virtio_bits[bit / 8] & (1 << (bit % 8))) + __set_bit(bit, bits); + } + kfree(virtio_bits); + + if (select == VIRTIO_INPUT_CFG_EV_BITS) + __set_bit(subsel, vi->idev->evbit); +} + +static void virtinput_cfg_abs(struct virtio_input *vi, int abs) +{ + u32 mi, ma, re, fu, fl; + + virtinput_cfg_select(vi, VIRTIO_INPUT_CFG_ABS_INFO, abs); + virtio_cread_le(vi->vdev, struct virtio_input_config, u.abs.min, &mi); + virtio_cread_le(vi->vdev, struct virtio_input_config, u.abs.max, &ma); + virtio_cread_le(vi->vdev, struct virtio_input_config, u.abs.res, &re); + virtio_cread_le(vi->vdev, struct virtio_input_config, u.abs.fuzz, &fu); + virtio_cread_le(vi->vdev, struct virtio_input_config, u.abs.flat, &fl); + input_set_abs_params(vi->idev, abs, mi, ma, fu, fl); + input_abs_set_res(vi->idev, abs, re); +} + +static int virtinput_init_vqs(struct virtio_input *vi) +{ + struct virtqueue_info vqs_info[] = { + { "events", virtinput_recv_events }, + { "status", virtinput_recv_status }, + }; + struct virtqueue *vqs[2]; + int err; + + err = virtio_find_vqs(vi->vdev, 2, vqs, vqs_info, NULL); + if (err) + return err; + vi->evt = vqs[0]; + vi->sts = vqs[1]; + + return 0; +} + +static void virtinput_fill_evt(struct virtio_input *vi) +{ + unsigned long flags; + int i, size; + + spin_lock_irqsave(&vi->lock, flags); + size = virtqueue_get_vring_size(vi->evt); + if (size > ARRAY_SIZE(vi->evts)) + size = ARRAY_SIZE(vi->evts); + for (i = 0; i < size; i++) + virtinput_queue_evtbuf(vi, &vi->evts[i]); + virtqueue_kick(vi->evt); + spin_unlock_irqrestore(&vi->lock, flags); +} + +static int virtinput_probe(struct virtio_device *vdev) +{ + struct virtio_input *vi; + unsigned long flags; + size_t size; + int abs, err, nslots; + + if (!virtio_has_feature(vdev, VIRTIO_F_VERSION_1)) + return -ENODEV; + + vi = kzalloc(sizeof(*vi), GFP_KERNEL); + if (!vi) + return -ENOMEM; + + vdev->priv = vi; + vi->vdev = vdev; + spin_lock_init(&vi->lock); + + err = virtinput_init_vqs(vi); + if (err) + goto err_init_vq; + + vi->idev = input_allocate_device(); + if (!vi->idev) { + err = -ENOMEM; + goto err_input_alloc; + } + input_set_drvdata(vi->idev, vi); + + size = virtinput_cfg_select(vi, VIRTIO_INPUT_CFG_ID_NAME, 0); + virtio_cread_bytes(vi->vdev, offsetof(struct virtio_input_config, + u.string), + vi->name, min(size, sizeof(vi->name))); + size = virtinput_cfg_select(vi, VIRTIO_INPUT_CFG_ID_SERIAL, 0); + virtio_cread_bytes(vi->vdev, offsetof(struct virtio_input_config, + u.string), + vi->serial, min(size, sizeof(vi->serial))); + snprintf(vi->phys, sizeof(vi->phys), + "virtio%d/input0", vdev->index); + vi->idev->name = vi->name; + vi->idev->phys = vi->phys; + vi->idev->uniq = vi->serial; + + size = virtinput_cfg_select(vi, VIRTIO_INPUT_CFG_ID_DEVIDS, 0); + if (size >= sizeof(struct virtio_input_devids)) { + virtio_cread_le(vi->vdev, struct virtio_input_config, + u.ids.bustype, &vi->idev->id.bustype); + virtio_cread_le(vi->vdev, struct virtio_input_config, + u.ids.vendor, &vi->idev->id.vendor); + virtio_cread_le(vi->vdev, struct virtio_input_config, + u.ids.product, &vi->idev->id.product); + virtio_cread_le(vi->vdev, struct virtio_input_config, + u.ids.version, &vi->idev->id.version); + } else { + vi->idev->id.bustype = BUS_VIRTUAL; + } + + virtinput_cfg_bits(vi, VIRTIO_INPUT_CFG_PROP_BITS, 0, + vi->idev->propbit, INPUT_PROP_CNT); + size = virtinput_cfg_select(vi, VIRTIO_INPUT_CFG_EV_BITS, EV_REP); + if (size) + __set_bit(EV_REP, vi->idev->evbit); + + vi->idev->dev.parent = &vdev->dev; + vi->idev->event = virtinput_status; + + /* device -> kernel */ + virtinput_cfg_bits(vi, VIRTIO_INPUT_CFG_EV_BITS, EV_KEY, + vi->idev->keybit, KEY_CNT); + virtinput_cfg_bits(vi, VIRTIO_INPUT_CFG_EV_BITS, EV_REL, + vi->idev->relbit, REL_CNT); + virtinput_cfg_bits(vi, VIRTIO_INPUT_CFG_EV_BITS, EV_ABS, + vi->idev->absbit, ABS_CNT); + virtinput_cfg_bits(vi, VIRTIO_INPUT_CFG_EV_BITS, EV_MSC, + vi->idev->mscbit, MSC_CNT); + virtinput_cfg_bits(vi, VIRTIO_INPUT_CFG_EV_BITS, EV_SW, + vi->idev->swbit, SW_CNT); + + /* kernel -> device */ + virtinput_cfg_bits(vi, VIRTIO_INPUT_CFG_EV_BITS, EV_LED, + vi->idev->ledbit, LED_CNT); + virtinput_cfg_bits(vi, VIRTIO_INPUT_CFG_EV_BITS, EV_SND, + vi->idev->sndbit, SND_CNT); + + if (test_bit(EV_ABS, vi->idev->evbit)) { + for (abs = 0; abs < ABS_CNT; abs++) { + if (!test_bit(abs, vi->idev->absbit)) + continue; + virtinput_cfg_abs(vi, abs); + } + + if (test_bit(ABS_MT_SLOT, vi->idev->absbit)) { + nslots = input_abs_get_max(vi->idev, ABS_MT_SLOT) + 1; + err = input_mt_init_slots(vi->idev, nslots, 0); + if (err) + goto err_mt_init_slots; + } + } + + virtio_device_ready(vdev); + vi->ready = true; + err = input_register_device(vi->idev); + if (err) + goto err_input_register; + + virtinput_fill_evt(vi); + return 0; + +err_input_register: + spin_lock_irqsave(&vi->lock, flags); + vi->ready = false; + spin_unlock_irqrestore(&vi->lock, flags); +err_mt_init_slots: + input_free_device(vi->idev); +err_input_alloc: + vdev->config->del_vqs(vdev); +err_init_vq: + kfree(vi); + return err; +} + +static void virtinput_remove(struct virtio_device *vdev) +{ + struct virtio_input *vi = vdev->priv; + void *buf; + unsigned long flags; + + spin_lock_irqsave(&vi->lock, flags); + vi->ready = false; + spin_unlock_irqrestore(&vi->lock, flags); + + input_unregister_device(vi->idev); + virtio_reset_device(vdev); + while ((buf = virtqueue_detach_unused_buf(vi->sts)) != NULL) + kfree(buf); + vdev->config->del_vqs(vdev); + kfree(vi); +} + +#ifdef CONFIG_PM_SLEEP +static int virtinput_freeze(struct virtio_device *vdev) +{ + struct virtio_input *vi = vdev->priv; + unsigned long flags; + void *buf; + + spin_lock_irqsave(&vi->lock, flags); + vi->ready = false; + spin_unlock_irqrestore(&vi->lock, flags); + + virtio_reset_device(vdev); + while ((buf = virtqueue_detach_unused_buf(vi->sts)) != NULL) + kfree(buf); + vdev->config->del_vqs(vdev); + return 0; +} + +static int virtinput_restore(struct virtio_device *vdev) +{ + struct virtio_input *vi = vdev->priv; + int err; + + err = virtinput_init_vqs(vi); + if (err) + return err; + + virtio_device_ready(vdev); + vi->ready = true; + virtinput_fill_evt(vi); + return 0; +} +#endif + +static unsigned int features[] = { + /* none */ +}; +static const struct virtio_device_id id_table[] = { + { VIRTIO_ID_INPUT, VIRTIO_DEV_ANY_ID }, + { 0 }, +}; + +static struct virtio_driver virtio_input_driver = { + .driver.name = KBUILD_MODNAME, + .feature_table = features, + .feature_table_size = ARRAY_SIZE(features), + .id_table = id_table, + .probe = virtinput_probe, + .remove = virtinput_remove, +#ifdef CONFIG_PM_SLEEP + .freeze = virtinput_freeze, + .restore = virtinput_restore, +#endif +}; + +module_virtio_driver(virtio_input_driver); +MODULE_DEVICE_TABLE(virtio, id_table); + +MODULE_LICENSE("GPL"); +MODULE_DESCRIPTION("Virtio input device driver"); +MODULE_AUTHOR("Gerd Hoffmann <kraxel@redhat.com>"); diff --git a/drivers/virtio/virtio_mem.c b/drivers/virtio/virtio_mem.c new file mode 100644 index 000000000000..1688ecd69a04 --- /dev/null +++ b/drivers/virtio/virtio_mem.c @@ -0,0 +1,3156 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * Virtio-mem device driver. + * + * Copyright Red Hat, Inc. 2020 + * + * Author(s): David Hildenbrand <david@redhat.com> + */ + +#include <linux/virtio.h> +#include <linux/virtio_mem.h> +#include <linux/workqueue.h> +#include <linux/slab.h> +#include <linux/module.h> +#include <linux/mm.h> +#include <linux/memory_hotplug.h> +#include <linux/memory.h> +#include <linux/hrtimer.h> +#include <linux/crash_dump.h> +#include <linux/mutex.h> +#include <linux/bitmap.h> +#include <linux/lockdep.h> +#include <linux/log2.h> +#include <linux/vmalloc.h> +#include <linux/suspend.h> + +#include <acpi/acpi_numa.h> + +static bool unplug_online = true; +module_param(unplug_online, bool, 0644); +MODULE_PARM_DESC(unplug_online, "Try to unplug online memory"); + +static bool force_bbm; +module_param(force_bbm, bool, 0444); +MODULE_PARM_DESC(force_bbm, + "Force Big Block Mode. Default is 0 (auto-selection)"); + +static unsigned long bbm_block_size; +module_param(bbm_block_size, ulong, 0444); +MODULE_PARM_DESC(bbm_block_size, + "Big Block size in bytes. Default is 0 (auto-detection)."); + +/* + * virtio-mem currently supports the following modes of operation: + * + * * Sub Block Mode (SBM): A Linux memory block spans 2..X subblocks (SB). The + * size of a Sub Block (SB) is determined based on the device block size, the + * pageblock size, and the maximum allocation granularity of the buddy. + * Subblocks within a Linux memory block might either be plugged or unplugged. + * Memory is added/removed to Linux MM in Linux memory block granularity. + * + * * Big Block Mode (BBM): A Big Block (BB) spans 1..X Linux memory blocks. + * Memory is added/removed to Linux MM in Big Block granularity. + * + * The mode is determined automatically based on the Linux memory block size + * and the device block size. + * + * User space / core MM (auto onlining) is responsible for onlining added + * Linux memory blocks - and for selecting a zone. Linux Memory Blocks are + * always onlined separately, and all memory within a Linux memory block is + * onlined to the same zone - virtio-mem relies on this behavior. + */ + +/* + * State of a Linux memory block in SBM. + */ +enum virtio_mem_sbm_mb_state { + /* Unplugged, not added to Linux. Can be reused later. */ + VIRTIO_MEM_SBM_MB_UNUSED = 0, + /* (Partially) plugged, not added to Linux. Error on add_memory(). */ + VIRTIO_MEM_SBM_MB_PLUGGED, + /* Fully plugged, fully added to Linux, offline. */ + VIRTIO_MEM_SBM_MB_OFFLINE, + /* Partially plugged, fully added to Linux, offline. */ + VIRTIO_MEM_SBM_MB_OFFLINE_PARTIAL, + /* Fully plugged, fully added to Linux, onlined to a kernel zone. */ + VIRTIO_MEM_SBM_MB_KERNEL, + /* Partially plugged, fully added to Linux, online to a kernel zone */ + VIRTIO_MEM_SBM_MB_KERNEL_PARTIAL, + /* Fully plugged, fully added to Linux, onlined to ZONE_MOVABLE. */ + VIRTIO_MEM_SBM_MB_MOVABLE, + /* Partially plugged, fully added to Linux, onlined to ZONE_MOVABLE. */ + VIRTIO_MEM_SBM_MB_MOVABLE_PARTIAL, + VIRTIO_MEM_SBM_MB_COUNT +}; + +/* + * State of a Big Block (BB) in BBM, covering 1..X Linux memory blocks. + */ +enum virtio_mem_bbm_bb_state { + /* Unplugged, not added to Linux. Can be reused later. */ + VIRTIO_MEM_BBM_BB_UNUSED = 0, + /* Plugged, not added to Linux. Error on add_memory(). */ + VIRTIO_MEM_BBM_BB_PLUGGED, + /* Plugged and added to Linux. */ + VIRTIO_MEM_BBM_BB_ADDED, + /* All online parts are fake-offline, ready to remove. */ + VIRTIO_MEM_BBM_BB_FAKE_OFFLINE, + VIRTIO_MEM_BBM_BB_COUNT +}; + +struct virtio_mem { + struct virtio_device *vdev; + + /* We might first have to unplug all memory when starting up. */ + bool unplug_all_required; + + /* Workqueue that processes the plug/unplug requests. */ + struct work_struct wq; + atomic_t wq_active; + atomic_t config_changed; + + /* Virtqueue for guest->host requests. */ + struct virtqueue *vq; + + /* Wait for a host response to a guest request. */ + wait_queue_head_t host_resp; + + /* Space for one guest request and the host response. */ + struct virtio_mem_req req; + struct virtio_mem_resp resp; + + /* The current size of the device. */ + uint64_t plugged_size; + /* The requested size of the device. */ + uint64_t requested_size; + + /* The device block size (for communicating with the device). */ + uint64_t device_block_size; + /* The determined node id for all memory of the device. */ + int nid; + /* Physical start address of the memory region. */ + uint64_t addr; + /* Maximum region size in bytes. */ + uint64_t region_size; + /* Usable region size in bytes. */ + uint64_t usable_region_size; + + /* The parent resource for all memory added via this device. */ + struct resource *parent_resource; + /* + * Copy of "System RAM (virtio_mem)" to be used for + * add_memory_driver_managed(). + */ + const char *resource_name; + /* Memory group identification. */ + int mgid; + + /* + * We don't want to add too much memory if it's not getting onlined, + * to avoid running OOM. Besides this threshold, we allow to have at + * least two offline blocks at a time (whatever is bigger). + */ +#define VIRTIO_MEM_DEFAULT_OFFLINE_THRESHOLD (1024 * 1024 * 1024) + atomic64_t offline_size; + uint64_t offline_threshold; + + /* If set, the driver is in SBM, otherwise in BBM. */ + bool in_sbm; + + union { + struct { + /* Id of the first memory block of this device. */ + unsigned long first_mb_id; + /* Id of the last usable memory block of this device. */ + unsigned long last_usable_mb_id; + /* Id of the next memory bock to prepare when needed. */ + unsigned long next_mb_id; + + /* The subblock size. */ + uint64_t sb_size; + /* The number of subblocks per Linux memory block. */ + uint32_t sbs_per_mb; + + /* + * Some of the Linux memory blocks tracked as "partially + * plugged" are completely unplugged and can be offlined + * and removed -- which previously failed. + */ + bool have_unplugged_mb; + + /* Summary of all memory block states. */ + unsigned long mb_count[VIRTIO_MEM_SBM_MB_COUNT]; + + /* + * One byte state per memory block. Allocated via + * vmalloc(). Resized (alloc+copy+free) on demand. + * + * With 128 MiB memory blocks, we have states for 512 + * GiB of memory in one 4 KiB page. + */ + uint8_t *mb_states; + + /* + * Bitmap: one bit per subblock. Allocated similar to + * sbm.mb_states. + * + * A set bit means the corresponding subblock is + * plugged, otherwise it's unblocked. + * + * With 4 MiB subblocks, we manage 128 GiB of memory + * in one 4 KiB page. + */ + unsigned long *sb_states; + } sbm; + + struct { + /* Id of the first big block of this device. */ + unsigned long first_bb_id; + /* Id of the last usable big block of this device. */ + unsigned long last_usable_bb_id; + /* Id of the next device bock to prepare when needed. */ + unsigned long next_bb_id; + + /* Summary of all big block states. */ + unsigned long bb_count[VIRTIO_MEM_BBM_BB_COUNT]; + + /* One byte state per big block. See sbm.mb_states. */ + uint8_t *bb_states; + + /* The block size used for plugging/adding/removing. */ + uint64_t bb_size; + } bbm; + }; + + /* + * Mutex that protects the sbm.mb_count, sbm.mb_states, + * sbm.sb_states, bbm.bb_count, and bbm.bb_states + * + * When this lock is held the pointers can't change, ONLINE and + * OFFLINE blocks can't change the state and no subblocks will get + * plugged/unplugged. + * + * In kdump mode, used to serialize requests, last_block_addr and + * last_block_plugged. + */ + struct mutex hotplug_mutex; + bool hotplug_active; + + /* An error occurred we cannot handle - stop processing requests. */ + bool broken; + + /* Cached valued of is_kdump_kernel() when the device was probed. */ + bool in_kdump; + + /* The driver is being removed. */ + spinlock_t removal_lock; + bool removing; + + /* Timer for retrying to plug/unplug memory. */ + struct hrtimer retry_timer; + unsigned int retry_timer_ms; +#define VIRTIO_MEM_RETRY_TIMER_MIN_MS 50000 +#define VIRTIO_MEM_RETRY_TIMER_MAX_MS 300000 + + /* Memory notifier (online/offline events). */ + struct notifier_block memory_notifier; + + /* Notifier to block hibernation image storing/reloading. */ + struct notifier_block pm_notifier; + +#ifdef CONFIG_PROC_VMCORE + /* vmcore callback for /proc/vmcore handling in kdump mode */ + struct vmcore_cb vmcore_cb; + uint64_t last_block_addr; + bool last_block_plugged; +#endif /* CONFIG_PROC_VMCORE */ + + /* Next device in the list of virtio-mem devices. */ + struct list_head next; +}; + +/* + * We have to share a single online_page callback among all virtio-mem + * devices. We use RCU to iterate the list in the callback. + */ +static DEFINE_MUTEX(virtio_mem_mutex); +static LIST_HEAD(virtio_mem_devices); + +static void virtio_mem_online_page_cb(struct page *page, unsigned int order); +static void virtio_mem_fake_offline_going_offline(unsigned long pfn, + unsigned long nr_pages); +static void virtio_mem_fake_offline_cancel_offline(unsigned long pfn, + unsigned long nr_pages); +static void virtio_mem_retry(struct virtio_mem *vm); +static int virtio_mem_create_resource(struct virtio_mem *vm); +static void virtio_mem_delete_resource(struct virtio_mem *vm); + +/* + * Register a virtio-mem device so it will be considered for the online_page + * callback. + */ +static int register_virtio_mem_device(struct virtio_mem *vm) +{ + int rc = 0; + + /* First device registers the callback. */ + mutex_lock(&virtio_mem_mutex); + if (list_empty(&virtio_mem_devices)) + rc = set_online_page_callback(&virtio_mem_online_page_cb); + if (!rc) + list_add_rcu(&vm->next, &virtio_mem_devices); + mutex_unlock(&virtio_mem_mutex); + + return rc; +} + +/* + * Unregister a virtio-mem device so it will no longer be considered for the + * online_page callback. + */ +static void unregister_virtio_mem_device(struct virtio_mem *vm) +{ + /* Last device unregisters the callback. */ + mutex_lock(&virtio_mem_mutex); + list_del_rcu(&vm->next); + if (list_empty(&virtio_mem_devices)) + restore_online_page_callback(&virtio_mem_online_page_cb); + mutex_unlock(&virtio_mem_mutex); + + synchronize_rcu(); +} + +/* + * Calculate the memory block id of a given address. + */ +static unsigned long virtio_mem_phys_to_mb_id(unsigned long addr) +{ + return addr / memory_block_size_bytes(); +} + +/* + * Calculate the physical start address of a given memory block id. + */ +static unsigned long virtio_mem_mb_id_to_phys(unsigned long mb_id) +{ + return mb_id * memory_block_size_bytes(); +} + +/* + * Calculate the big block id of a given address. + */ +static unsigned long virtio_mem_phys_to_bb_id(struct virtio_mem *vm, + uint64_t addr) +{ + return addr / vm->bbm.bb_size; +} + +/* + * Calculate the physical start address of a given big block id. + */ +static uint64_t virtio_mem_bb_id_to_phys(struct virtio_mem *vm, + unsigned long bb_id) +{ + return bb_id * vm->bbm.bb_size; +} + +/* + * Calculate the subblock id of a given address. + */ +static unsigned long virtio_mem_phys_to_sb_id(struct virtio_mem *vm, + unsigned long addr) +{ + const unsigned long mb_id = virtio_mem_phys_to_mb_id(addr); + const unsigned long mb_addr = virtio_mem_mb_id_to_phys(mb_id); + + return (addr - mb_addr) / vm->sbm.sb_size; +} + +/* + * Set the state of a big block, taking care of the state counter. + */ +static void virtio_mem_bbm_set_bb_state(struct virtio_mem *vm, + unsigned long bb_id, + enum virtio_mem_bbm_bb_state state) +{ + const unsigned long idx = bb_id - vm->bbm.first_bb_id; + enum virtio_mem_bbm_bb_state old_state; + + old_state = vm->bbm.bb_states[idx]; + vm->bbm.bb_states[idx] = state; + + BUG_ON(vm->bbm.bb_count[old_state] == 0); + vm->bbm.bb_count[old_state]--; + vm->bbm.bb_count[state]++; +} + +/* + * Get the state of a big block. + */ +static enum virtio_mem_bbm_bb_state virtio_mem_bbm_get_bb_state(struct virtio_mem *vm, + unsigned long bb_id) +{ + return vm->bbm.bb_states[bb_id - vm->bbm.first_bb_id]; +} + +/* + * Prepare the big block state array for the next big block. + */ +static int virtio_mem_bbm_bb_states_prepare_next_bb(struct virtio_mem *vm) +{ + unsigned long old_bytes = vm->bbm.next_bb_id - vm->bbm.first_bb_id; + unsigned long new_bytes = old_bytes + 1; + int old_pages = PFN_UP(old_bytes); + int new_pages = PFN_UP(new_bytes); + uint8_t *new_array; + + if (vm->bbm.bb_states && old_pages == new_pages) + return 0; + + new_array = vzalloc(new_pages * PAGE_SIZE); + if (!new_array) + return -ENOMEM; + + mutex_lock(&vm->hotplug_mutex); + if (vm->bbm.bb_states) + memcpy(new_array, vm->bbm.bb_states, old_pages * PAGE_SIZE); + vfree(vm->bbm.bb_states); + vm->bbm.bb_states = new_array; + mutex_unlock(&vm->hotplug_mutex); + + return 0; +} + +#define virtio_mem_bbm_for_each_bb(_vm, _bb_id, _state) \ + for (_bb_id = vm->bbm.first_bb_id; \ + _bb_id < vm->bbm.next_bb_id && _vm->bbm.bb_count[_state]; \ + _bb_id++) \ + if (virtio_mem_bbm_get_bb_state(_vm, _bb_id) == _state) + +#define virtio_mem_bbm_for_each_bb_rev(_vm, _bb_id, _state) \ + for (_bb_id = vm->bbm.next_bb_id - 1; \ + _bb_id >= vm->bbm.first_bb_id && _vm->bbm.bb_count[_state]; \ + _bb_id--) \ + if (virtio_mem_bbm_get_bb_state(_vm, _bb_id) == _state) + +/* + * Set the state of a memory block, taking care of the state counter. + */ +static void virtio_mem_sbm_set_mb_state(struct virtio_mem *vm, + unsigned long mb_id, uint8_t state) +{ + const unsigned long idx = mb_id - vm->sbm.first_mb_id; + uint8_t old_state; + + old_state = vm->sbm.mb_states[idx]; + vm->sbm.mb_states[idx] = state; + + BUG_ON(vm->sbm.mb_count[old_state] == 0); + vm->sbm.mb_count[old_state]--; + vm->sbm.mb_count[state]++; +} + +/* + * Get the state of a memory block. + */ +static uint8_t virtio_mem_sbm_get_mb_state(struct virtio_mem *vm, + unsigned long mb_id) +{ + const unsigned long idx = mb_id - vm->sbm.first_mb_id; + + return vm->sbm.mb_states[idx]; +} + +/* + * Prepare the state array for the next memory block. + */ +static int virtio_mem_sbm_mb_states_prepare_next_mb(struct virtio_mem *vm) +{ + int old_pages = PFN_UP(vm->sbm.next_mb_id - vm->sbm.first_mb_id); + int new_pages = PFN_UP(vm->sbm.next_mb_id - vm->sbm.first_mb_id + 1); + uint8_t *new_array; + + if (vm->sbm.mb_states && old_pages == new_pages) + return 0; + + new_array = vzalloc(new_pages * PAGE_SIZE); + if (!new_array) + return -ENOMEM; + + mutex_lock(&vm->hotplug_mutex); + if (vm->sbm.mb_states) + memcpy(new_array, vm->sbm.mb_states, old_pages * PAGE_SIZE); + vfree(vm->sbm.mb_states); + vm->sbm.mb_states = new_array; + mutex_unlock(&vm->hotplug_mutex); + + return 0; +} + +#define virtio_mem_sbm_for_each_mb(_vm, _mb_id, _state) \ + for (_mb_id = _vm->sbm.first_mb_id; \ + _mb_id < _vm->sbm.next_mb_id && _vm->sbm.mb_count[_state]; \ + _mb_id++) \ + if (virtio_mem_sbm_get_mb_state(_vm, _mb_id) == _state) + +#define virtio_mem_sbm_for_each_mb_rev(_vm, _mb_id, _state) \ + for (_mb_id = _vm->sbm.next_mb_id - 1; \ + _mb_id >= _vm->sbm.first_mb_id && _vm->sbm.mb_count[_state]; \ + _mb_id--) \ + if (virtio_mem_sbm_get_mb_state(_vm, _mb_id) == _state) + +/* + * Calculate the bit number in the subblock bitmap for the given subblock + * inside the given memory block. + */ +static int virtio_mem_sbm_sb_state_bit_nr(struct virtio_mem *vm, + unsigned long mb_id, int sb_id) +{ + return (mb_id - vm->sbm.first_mb_id) * vm->sbm.sbs_per_mb + sb_id; +} + +/* + * Mark all selected subblocks plugged. + * + * Will not modify the state of the memory block. + */ +static void virtio_mem_sbm_set_sb_plugged(struct virtio_mem *vm, + unsigned long mb_id, int sb_id, + int count) +{ + const int bit = virtio_mem_sbm_sb_state_bit_nr(vm, mb_id, sb_id); + + __bitmap_set(vm->sbm.sb_states, bit, count); +} + +/* + * Mark all selected subblocks unplugged. + * + * Will not modify the state of the memory block. + */ +static void virtio_mem_sbm_set_sb_unplugged(struct virtio_mem *vm, + unsigned long mb_id, int sb_id, + int count) +{ + const int bit = virtio_mem_sbm_sb_state_bit_nr(vm, mb_id, sb_id); + + __bitmap_clear(vm->sbm.sb_states, bit, count); +} + +/* + * Test if all selected subblocks are plugged. + */ +static bool virtio_mem_sbm_test_sb_plugged(struct virtio_mem *vm, + unsigned long mb_id, int sb_id, + int count) +{ + const int bit = virtio_mem_sbm_sb_state_bit_nr(vm, mb_id, sb_id); + + if (count == 1) + return test_bit(bit, vm->sbm.sb_states); + + /* TODO: Helper similar to bitmap_set() */ + return find_next_zero_bit(vm->sbm.sb_states, bit + count, bit) >= + bit + count; +} + +/* + * Test if all selected subblocks are unplugged. + */ +static bool virtio_mem_sbm_test_sb_unplugged(struct virtio_mem *vm, + unsigned long mb_id, int sb_id, + int count) +{ + const int bit = virtio_mem_sbm_sb_state_bit_nr(vm, mb_id, sb_id); + + /* TODO: Helper similar to bitmap_set() */ + return find_next_bit(vm->sbm.sb_states, bit + count, bit) >= + bit + count; +} + +/* + * Find the first unplugged subblock. Returns vm->sbm.sbs_per_mb in case there is + * none. + */ +static int virtio_mem_sbm_first_unplugged_sb(struct virtio_mem *vm, + unsigned long mb_id) +{ + const int bit = virtio_mem_sbm_sb_state_bit_nr(vm, mb_id, 0); + + return find_next_zero_bit(vm->sbm.sb_states, + bit + vm->sbm.sbs_per_mb, bit) - bit; +} + +/* + * Prepare the subblock bitmap for the next memory block. + */ +static int virtio_mem_sbm_sb_states_prepare_next_mb(struct virtio_mem *vm) +{ + const unsigned long old_nb_mb = vm->sbm.next_mb_id - vm->sbm.first_mb_id; + const unsigned long old_nb_bits = old_nb_mb * vm->sbm.sbs_per_mb; + const unsigned long new_nb_bits = (old_nb_mb + 1) * vm->sbm.sbs_per_mb; + int old_pages = PFN_UP(BITS_TO_LONGS(old_nb_bits) * sizeof(long)); + int new_pages = PFN_UP(BITS_TO_LONGS(new_nb_bits) * sizeof(long)); + unsigned long *new_bitmap, *old_bitmap; + + if (vm->sbm.sb_states && old_pages == new_pages) + return 0; + + new_bitmap = vzalloc(new_pages * PAGE_SIZE); + if (!new_bitmap) + return -ENOMEM; + + mutex_lock(&vm->hotplug_mutex); + if (vm->sbm.sb_states) + memcpy(new_bitmap, vm->sbm.sb_states, old_pages * PAGE_SIZE); + + old_bitmap = vm->sbm.sb_states; + vm->sbm.sb_states = new_bitmap; + mutex_unlock(&vm->hotplug_mutex); + + vfree(old_bitmap); + return 0; +} + +/* + * Test if we could add memory without creating too much offline memory - + * to avoid running OOM if memory is getting onlined deferred. + */ +static bool virtio_mem_could_add_memory(struct virtio_mem *vm, uint64_t size) +{ + if (WARN_ON_ONCE(size > vm->offline_threshold)) + return false; + + return atomic64_read(&vm->offline_size) + size <= vm->offline_threshold; +} + +/* + * Try adding memory to Linux. Will usually only fail if out of memory. + * + * Must not be called with the vm->hotplug_mutex held (possible deadlock with + * onlining code). + * + * Will not modify the state of memory blocks in virtio-mem. + */ +static int virtio_mem_add_memory(struct virtio_mem *vm, uint64_t addr, + uint64_t size) +{ + int rc; + + /* + * When force-unloading the driver and we still have memory added to + * Linux, the resource name has to stay. + */ + if (!vm->resource_name) { + vm->resource_name = kstrdup_const("System RAM (virtio_mem)", + GFP_KERNEL); + if (!vm->resource_name) + return -ENOMEM; + } + + dev_dbg(&vm->vdev->dev, "adding memory: 0x%llx - 0x%llx\n", addr, + addr + size - 1); + /* Memory might get onlined immediately. */ + atomic64_add(size, &vm->offline_size); + rc = add_memory_driver_managed(vm->mgid, addr, size, vm->resource_name, + MHP_MERGE_RESOURCE | MHP_NID_IS_MGID); + if (rc) { + atomic64_sub(size, &vm->offline_size); + dev_warn(&vm->vdev->dev, "adding memory failed: %d\n", rc); + /* + * TODO: Linux MM does not properly clean up yet in all cases + * where adding of memory failed - especially on -ENOMEM. + */ + } + return rc; +} + +/* + * See virtio_mem_add_memory(): Try adding a single Linux memory block. + */ +static int virtio_mem_sbm_add_mb(struct virtio_mem *vm, unsigned long mb_id) +{ + const uint64_t addr = virtio_mem_mb_id_to_phys(mb_id); + const uint64_t size = memory_block_size_bytes(); + + return virtio_mem_add_memory(vm, addr, size); +} + +/* + * See virtio_mem_add_memory(): Try adding a big block. + */ +static int virtio_mem_bbm_add_bb(struct virtio_mem *vm, unsigned long bb_id) +{ + const uint64_t addr = virtio_mem_bb_id_to_phys(vm, bb_id); + const uint64_t size = vm->bbm.bb_size; + + return virtio_mem_add_memory(vm, addr, size); +} + +/* + * Try removing memory from Linux. Will only fail if memory blocks aren't + * offline. + * + * Must not be called with the vm->hotplug_mutex held (possible deadlock with + * onlining code). + * + * Will not modify the state of memory blocks in virtio-mem. + */ +static int virtio_mem_remove_memory(struct virtio_mem *vm, uint64_t addr, + uint64_t size) +{ + int rc; + + dev_dbg(&vm->vdev->dev, "removing memory: 0x%llx - 0x%llx\n", addr, + addr + size - 1); + rc = remove_memory(addr, size); + if (!rc) { + atomic64_sub(size, &vm->offline_size); + /* + * We might have freed up memory we can now unplug, retry + * immediately instead of waiting. + */ + virtio_mem_retry(vm); + } else { + dev_dbg(&vm->vdev->dev, "removing memory failed: %d\n", rc); + } + return rc; +} + +/* + * See virtio_mem_remove_memory(): Try removing a single Linux memory block. + */ +static int virtio_mem_sbm_remove_mb(struct virtio_mem *vm, unsigned long mb_id) +{ + const uint64_t addr = virtio_mem_mb_id_to_phys(mb_id); + const uint64_t size = memory_block_size_bytes(); + + return virtio_mem_remove_memory(vm, addr, size); +} + +/* + * Try offlining and removing memory from Linux. + * + * Must not be called with the vm->hotplug_mutex held (possible deadlock with + * onlining code). + * + * Will not modify the state of memory blocks in virtio-mem. + */ +static int virtio_mem_offline_and_remove_memory(struct virtio_mem *vm, + uint64_t addr, + uint64_t size) +{ + int rc; + + dev_dbg(&vm->vdev->dev, + "offlining and removing memory: 0x%llx - 0x%llx\n", addr, + addr + size - 1); + + rc = offline_and_remove_memory(addr, size); + if (!rc) { + atomic64_sub(size, &vm->offline_size); + /* + * We might have freed up memory we can now unplug, retry + * immediately instead of waiting. + */ + virtio_mem_retry(vm); + return 0; + } + dev_dbg(&vm->vdev->dev, "offlining and removing memory failed: %d\n", rc); + /* + * We don't really expect this to fail, because we fake-offlined all + * memory already. But it could fail in corner cases. + */ + WARN_ON_ONCE(rc != -ENOMEM && rc != -EBUSY); + return rc == -ENOMEM ? -ENOMEM : -EBUSY; +} + +/* + * See virtio_mem_offline_and_remove_memory(): Try offlining and removing + * a single Linux memory block. + */ +static int virtio_mem_sbm_offline_and_remove_mb(struct virtio_mem *vm, + unsigned long mb_id) +{ + const uint64_t addr = virtio_mem_mb_id_to_phys(mb_id); + const uint64_t size = memory_block_size_bytes(); + + return virtio_mem_offline_and_remove_memory(vm, addr, size); +} + +/* + * Try (offlining and) removing memory from Linux in case all subblocks are + * unplugged. Can be called on online and offline memory blocks. + * + * May modify the state of memory blocks in virtio-mem. + */ +static int virtio_mem_sbm_try_remove_unplugged_mb(struct virtio_mem *vm, + unsigned long mb_id) +{ + int rc; + + /* + * Once all subblocks of a memory block were unplugged, offline and + * remove it. + */ + if (!virtio_mem_sbm_test_sb_unplugged(vm, mb_id, 0, vm->sbm.sbs_per_mb)) + return 0; + + /* offline_and_remove_memory() works for online and offline memory. */ + mutex_unlock(&vm->hotplug_mutex); + rc = virtio_mem_sbm_offline_and_remove_mb(vm, mb_id); + mutex_lock(&vm->hotplug_mutex); + if (!rc) + virtio_mem_sbm_set_mb_state(vm, mb_id, + VIRTIO_MEM_SBM_MB_UNUSED); + return rc; +} + +/* + * See virtio_mem_offline_and_remove_memory(): Try to offline and remove a + * all Linux memory blocks covered by the big block. + */ +static int virtio_mem_bbm_offline_and_remove_bb(struct virtio_mem *vm, + unsigned long bb_id) +{ + const uint64_t addr = virtio_mem_bb_id_to_phys(vm, bb_id); + const uint64_t size = vm->bbm.bb_size; + + return virtio_mem_offline_and_remove_memory(vm, addr, size); +} + +/* + * Trigger the workqueue so the device can perform its magic. + */ +static void virtio_mem_retry(struct virtio_mem *vm) +{ + unsigned long flags; + + spin_lock_irqsave(&vm->removal_lock, flags); + if (!vm->removing) + queue_work(system_freezable_wq, &vm->wq); + spin_unlock_irqrestore(&vm->removal_lock, flags); +} + +static int virtio_mem_translate_node_id(struct virtio_mem *vm, uint16_t node_id) +{ + int node = NUMA_NO_NODE; + +#if defined(CONFIG_ACPI_NUMA) + if (virtio_has_feature(vm->vdev, VIRTIO_MEM_F_ACPI_PXM)) + node = pxm_to_node(node_id); +#endif + return node; +} + +/* + * Test if a virtio-mem device overlaps with the given range. Can be called + * from (notifier) callbacks lockless. + */ +static bool virtio_mem_overlaps_range(struct virtio_mem *vm, uint64_t start, + uint64_t size) +{ + return start < vm->addr + vm->region_size && vm->addr < start + size; +} + +/* + * Test if a virtio-mem device contains a given range. Can be called from + * (notifier) callbacks lockless. + */ +static bool virtio_mem_contains_range(struct virtio_mem *vm, uint64_t start, + uint64_t size) +{ + return start >= vm->addr && start + size <= vm->addr + vm->region_size; +} + +static int virtio_mem_sbm_notify_going_online(struct virtio_mem *vm, + unsigned long mb_id) +{ + switch (virtio_mem_sbm_get_mb_state(vm, mb_id)) { + case VIRTIO_MEM_SBM_MB_OFFLINE_PARTIAL: + case VIRTIO_MEM_SBM_MB_OFFLINE: + return NOTIFY_OK; + default: + break; + } + dev_warn_ratelimited(&vm->vdev->dev, + "memory block onlining denied\n"); + return NOTIFY_BAD; +} + +static void virtio_mem_sbm_notify_offline(struct virtio_mem *vm, + unsigned long mb_id) +{ + switch (virtio_mem_sbm_get_mb_state(vm, mb_id)) { + case VIRTIO_MEM_SBM_MB_KERNEL_PARTIAL: + case VIRTIO_MEM_SBM_MB_MOVABLE_PARTIAL: + virtio_mem_sbm_set_mb_state(vm, mb_id, + VIRTIO_MEM_SBM_MB_OFFLINE_PARTIAL); + break; + case VIRTIO_MEM_SBM_MB_KERNEL: + case VIRTIO_MEM_SBM_MB_MOVABLE: + virtio_mem_sbm_set_mb_state(vm, mb_id, + VIRTIO_MEM_SBM_MB_OFFLINE); + break; + default: + BUG(); + break; + } +} + +static void virtio_mem_sbm_notify_online(struct virtio_mem *vm, + unsigned long mb_id, + unsigned long start_pfn) +{ + const bool is_movable = is_zone_movable_page(pfn_to_page(start_pfn)); + int new_state; + + switch (virtio_mem_sbm_get_mb_state(vm, mb_id)) { + case VIRTIO_MEM_SBM_MB_OFFLINE_PARTIAL: + new_state = VIRTIO_MEM_SBM_MB_KERNEL_PARTIAL; + if (is_movable) + new_state = VIRTIO_MEM_SBM_MB_MOVABLE_PARTIAL; + break; + case VIRTIO_MEM_SBM_MB_OFFLINE: + new_state = VIRTIO_MEM_SBM_MB_KERNEL; + if (is_movable) + new_state = VIRTIO_MEM_SBM_MB_MOVABLE; + break; + default: + BUG(); + break; + } + virtio_mem_sbm_set_mb_state(vm, mb_id, new_state); +} + +static void virtio_mem_sbm_notify_going_offline(struct virtio_mem *vm, + unsigned long mb_id) +{ + const unsigned long nr_pages = PFN_DOWN(vm->sbm.sb_size); + unsigned long pfn; + int sb_id; + + for (sb_id = 0; sb_id < vm->sbm.sbs_per_mb; sb_id++) { + if (virtio_mem_sbm_test_sb_plugged(vm, mb_id, sb_id, 1)) + continue; + pfn = PFN_DOWN(virtio_mem_mb_id_to_phys(mb_id) + + sb_id * vm->sbm.sb_size); + virtio_mem_fake_offline_going_offline(pfn, nr_pages); + } +} + +static void virtio_mem_sbm_notify_cancel_offline(struct virtio_mem *vm, + unsigned long mb_id) +{ + const unsigned long nr_pages = PFN_DOWN(vm->sbm.sb_size); + unsigned long pfn; + int sb_id; + + for (sb_id = 0; sb_id < vm->sbm.sbs_per_mb; sb_id++) { + if (virtio_mem_sbm_test_sb_plugged(vm, mb_id, sb_id, 1)) + continue; + pfn = PFN_DOWN(virtio_mem_mb_id_to_phys(mb_id) + + sb_id * vm->sbm.sb_size); + virtio_mem_fake_offline_cancel_offline(pfn, nr_pages); + } +} + +static void virtio_mem_bbm_notify_going_offline(struct virtio_mem *vm, + unsigned long bb_id, + unsigned long pfn, + unsigned long nr_pages) +{ + /* + * When marked as "fake-offline", all online memory of this device block + * is allocated by us. Otherwise, we don't have any memory allocated. + */ + if (virtio_mem_bbm_get_bb_state(vm, bb_id) != + VIRTIO_MEM_BBM_BB_FAKE_OFFLINE) + return; + virtio_mem_fake_offline_going_offline(pfn, nr_pages); +} + +static void virtio_mem_bbm_notify_cancel_offline(struct virtio_mem *vm, + unsigned long bb_id, + unsigned long pfn, + unsigned long nr_pages) +{ + if (virtio_mem_bbm_get_bb_state(vm, bb_id) != + VIRTIO_MEM_BBM_BB_FAKE_OFFLINE) + return; + virtio_mem_fake_offline_cancel_offline(pfn, nr_pages); +} + +/* + * This callback will either be called synchronously from add_memory() or + * asynchronously (e.g., triggered via user space). We have to be careful + * with locking when calling add_memory(). + */ +static int virtio_mem_memory_notifier_cb(struct notifier_block *nb, + unsigned long action, void *arg) +{ + struct virtio_mem *vm = container_of(nb, struct virtio_mem, + memory_notifier); + struct memory_notify *mhp = arg; + const unsigned long start = PFN_PHYS(mhp->start_pfn); + const unsigned long size = PFN_PHYS(mhp->nr_pages); + int rc = NOTIFY_OK; + unsigned long id; + + if (!virtio_mem_overlaps_range(vm, start, size)) + return NOTIFY_DONE; + + if (vm->in_sbm) { + id = virtio_mem_phys_to_mb_id(start); + /* + * In SBM, we add memory in separate memory blocks - we expect + * it to be onlined/offlined in the same granularity. Bail out + * if this ever changes. + */ + if (WARN_ON_ONCE(size != memory_block_size_bytes() || + !IS_ALIGNED(start, memory_block_size_bytes()))) + return NOTIFY_BAD; + } else { + id = virtio_mem_phys_to_bb_id(vm, start); + /* + * In BBM, we only care about onlining/offlining happening + * within a single big block, we don't care about the + * actual granularity as we don't track individual Linux + * memory blocks. + */ + if (WARN_ON_ONCE(id != virtio_mem_phys_to_bb_id(vm, start + size - 1))) + return NOTIFY_BAD; + } + + /* + * Avoid circular locking lockdep warnings. We lock the mutex + * e.g., in MEM_GOING_ONLINE and unlock it in MEM_ONLINE. The + * blocking_notifier_call_chain() has it's own lock, which gets unlocked + * between both notifier calls and will bail out. False positive. + */ + lockdep_off(); + + switch (action) { + case MEM_GOING_OFFLINE: + mutex_lock(&vm->hotplug_mutex); + if (vm->removing) { + rc = notifier_from_errno(-EBUSY); + mutex_unlock(&vm->hotplug_mutex); + break; + } + vm->hotplug_active = true; + if (vm->in_sbm) + virtio_mem_sbm_notify_going_offline(vm, id); + else + virtio_mem_bbm_notify_going_offline(vm, id, + mhp->start_pfn, + mhp->nr_pages); + break; + case MEM_GOING_ONLINE: + mutex_lock(&vm->hotplug_mutex); + if (vm->removing) { + rc = notifier_from_errno(-EBUSY); + mutex_unlock(&vm->hotplug_mutex); + break; + } + vm->hotplug_active = true; + if (vm->in_sbm) + rc = virtio_mem_sbm_notify_going_online(vm, id); + break; + case MEM_OFFLINE: + if (vm->in_sbm) + virtio_mem_sbm_notify_offline(vm, id); + + atomic64_add(size, &vm->offline_size); + /* + * Trigger the workqueue. Now that we have some offline memory, + * maybe we can handle pending unplug requests. + */ + if (!unplug_online) + virtio_mem_retry(vm); + + vm->hotplug_active = false; + mutex_unlock(&vm->hotplug_mutex); + break; + case MEM_ONLINE: + if (vm->in_sbm) + virtio_mem_sbm_notify_online(vm, id, mhp->start_pfn); + + atomic64_sub(size, &vm->offline_size); + /* + * Start adding more memory once we onlined half of our + * threshold. Don't trigger if it's possibly due to our actipn + * (e.g., us adding memory which gets onlined immediately from + * the core). + */ + if (!atomic_read(&vm->wq_active) && + virtio_mem_could_add_memory(vm, vm->offline_threshold / 2)) + virtio_mem_retry(vm); + + vm->hotplug_active = false; + mutex_unlock(&vm->hotplug_mutex); + break; + case MEM_CANCEL_OFFLINE: + if (!vm->hotplug_active) + break; + if (vm->in_sbm) + virtio_mem_sbm_notify_cancel_offline(vm, id); + else + virtio_mem_bbm_notify_cancel_offline(vm, id, + mhp->start_pfn, + mhp->nr_pages); + vm->hotplug_active = false; + mutex_unlock(&vm->hotplug_mutex); + break; + case MEM_CANCEL_ONLINE: + if (!vm->hotplug_active) + break; + vm->hotplug_active = false; + mutex_unlock(&vm->hotplug_mutex); + break; + default: + break; + } + + lockdep_on(); + + return rc; +} + +static int virtio_mem_pm_notifier_cb(struct notifier_block *nb, + unsigned long action, void *arg) +{ + struct virtio_mem *vm = container_of(nb, struct virtio_mem, + pm_notifier); + switch (action) { + case PM_HIBERNATION_PREPARE: + case PM_RESTORE_PREPARE: + /* + * When restarting the VM, all memory is unplugged. Don't + * allow to hibernate and restore from an image. + */ + dev_err(&vm->vdev->dev, "hibernation is not supported.\n"); + return NOTIFY_BAD; + default: + return NOTIFY_OK; + } +} + +/* + * Set a range of pages PG_offline. Remember pages that were never onlined + * (via generic_online_page()) using PageDirty(). + */ +static void virtio_mem_set_fake_offline(unsigned long pfn, + unsigned long nr_pages, bool onlined) +{ + page_offline_begin(); + for (; nr_pages--; pfn++) { + struct page *page = pfn_to_page(pfn); + + if (!onlined) + /* + * Pages that have not been onlined yet were initialized + * to PageOffline(). Remember that we have to route them + * through generic_online_page(). + */ + SetPageDirty(page); + else + __SetPageOffline(page); + VM_WARN_ON_ONCE(!PageOffline(page)); + } + page_offline_end(); +} + +/* + * Clear PG_offline from a range of pages. If the pages were never onlined, + * (via generic_online_page()), clear PageDirty(). + */ +static void virtio_mem_clear_fake_offline(unsigned long pfn, + unsigned long nr_pages, bool onlined) +{ + for (; nr_pages--; pfn++) { + struct page *page = pfn_to_page(pfn); + + if (!onlined) + /* generic_online_page() will clear PageOffline(). */ + ClearPageDirty(page); + else + __ClearPageOffline(page); + } +} + +/* + * Release a range of fake-offline pages to the buddy, effectively + * fake-onlining them. + */ +static void virtio_mem_fake_online(unsigned long pfn, unsigned long nr_pages) +{ + unsigned long order = MAX_PAGE_ORDER; + unsigned long i; + + /* + * We might get called for ranges that don't cover properly aligned + * MAX_PAGE_ORDER pages; however, we can only online properly aligned + * pages with an order of MAX_PAGE_ORDER at maximum. + */ + while (!IS_ALIGNED(pfn | nr_pages, 1 << order)) + order--; + + for (i = 0; i < nr_pages; i += 1 << order) { + struct page *page = pfn_to_page(pfn + i); + + /* + * If the page is PageDirty(), it was kept fake-offline when + * onlining the memory block. Otherwise, it was allocated + * using alloc_contig_range(). All pages in a subblock are + * alike. + */ + if (PageDirty(page)) { + virtio_mem_clear_fake_offline(pfn + i, 1 << order, false); + generic_online_page(page, order); + } else { + virtio_mem_clear_fake_offline(pfn + i, 1 << order, true); + free_contig_range(pfn + i, 1 << order); + adjust_managed_page_count(page, 1 << order); + } + } +} + +/* + * Try to allocate a range, marking pages fake-offline, effectively + * fake-offlining them. + */ +static int virtio_mem_fake_offline(struct virtio_mem *vm, unsigned long pfn, + unsigned long nr_pages) +{ + const bool is_movable = is_zone_movable_page(pfn_to_page(pfn)); + int rc, retry_count; + + /* + * TODO: We want an alloc_contig_range() mode that tries to allocate + * harder (e.g., dealing with temporarily pinned pages, PCP), especially + * with ZONE_MOVABLE. So for now, retry a couple of times with + * ZONE_MOVABLE before giving up - because that zone is supposed to give + * some guarantees. + */ + for (retry_count = 0; retry_count < 5; retry_count++) { + /* + * If the config changed, stop immediately and go back to the + * main loop: avoid trying to keep unplugging if the device + * might have decided to not remove any more memory. + */ + if (atomic_read(&vm->config_changed)) + return -EAGAIN; + + rc = alloc_contig_range(pfn, pfn + nr_pages, ACR_FLAGS_NONE, + GFP_KERNEL); + if (rc == -ENOMEM) + /* whoops, out of memory */ + return rc; + else if (rc && !is_movable) + break; + else if (rc) + continue; + + virtio_mem_set_fake_offline(pfn, nr_pages, true); + adjust_managed_page_count(pfn_to_page(pfn), -nr_pages); + return 0; + } + + return -EBUSY; +} + +/* + * Handle fake-offline pages when memory is going offline - such that the + * pages can be skipped by mm-core when offlining. + */ +static void virtio_mem_fake_offline_going_offline(unsigned long pfn, + unsigned long nr_pages) +{ + struct page *page; + unsigned long i; + + /* Drop our reference to the pages so the memory can get offlined. */ + for (i = 0; i < nr_pages; i++) { + page = pfn_to_page(pfn + i); + if (WARN_ON(!page_ref_dec_and_test(page))) + dump_page(page, "fake-offline page referenced"); + } +} + +/* + * Handle fake-offline pages when memory offlining is canceled - to undo + * what we did in virtio_mem_fake_offline_going_offline(). + */ +static void virtio_mem_fake_offline_cancel_offline(unsigned long pfn, + unsigned long nr_pages) +{ + unsigned long i; + + /* + * Get the reference again that we dropped via page_ref_dec_and_test() + * when going offline. + */ + for (i = 0; i < nr_pages; i++) + page_ref_inc(pfn_to_page(pfn + i)); +} + +static void virtio_mem_online_page(struct virtio_mem *vm, + struct page *page, unsigned int order) +{ + const unsigned long start = page_to_phys(page); + const unsigned long end = start + PFN_PHYS(1 << order); + unsigned long addr, next, id, sb_id, count; + bool do_online; + + /* + * We can get called with any order up to MAX_PAGE_ORDER. If our subblock + * size is smaller than that and we have a mixture of plugged and + * unplugged subblocks within such a page, we have to process in + * smaller granularity. In that case we'll adjust the order exactly once + * within the loop. + */ + for (addr = start; addr < end; ) { + next = addr + PFN_PHYS(1 << order); + + if (vm->in_sbm) { + id = virtio_mem_phys_to_mb_id(addr); + sb_id = virtio_mem_phys_to_sb_id(vm, addr); + count = virtio_mem_phys_to_sb_id(vm, next - 1) - sb_id + 1; + + if (virtio_mem_sbm_test_sb_plugged(vm, id, sb_id, count)) { + /* Fully plugged. */ + do_online = true; + } else if (count == 1 || + virtio_mem_sbm_test_sb_unplugged(vm, id, sb_id, count)) { + /* Fully unplugged. */ + do_online = false; + } else { + /* + * Mixture, process sub-blocks instead. This + * will be at least the size of a pageblock. + * We'll run into this case exactly once. + */ + order = ilog2(vm->sbm.sb_size) - PAGE_SHIFT; + do_online = virtio_mem_sbm_test_sb_plugged(vm, id, sb_id, 1); + continue; + } + } else { + /* + * If the whole block is marked fake offline, keep + * everything that way. + */ + id = virtio_mem_phys_to_bb_id(vm, addr); + do_online = virtio_mem_bbm_get_bb_state(vm, id) != + VIRTIO_MEM_BBM_BB_FAKE_OFFLINE; + } + + if (do_online) + generic_online_page(pfn_to_page(PFN_DOWN(addr)), order); + else + virtio_mem_set_fake_offline(PFN_DOWN(addr), 1 << order, + false); + addr = next; + } +} + +static void virtio_mem_online_page_cb(struct page *page, unsigned int order) +{ + const unsigned long addr = page_to_phys(page); + struct virtio_mem *vm; + + rcu_read_lock(); + list_for_each_entry_rcu(vm, &virtio_mem_devices, next) { + /* + * Pages we're onlining will never cross memory blocks and, + * therefore, not virtio-mem devices. + */ + if (!virtio_mem_contains_range(vm, addr, PFN_PHYS(1 << order))) + continue; + + /* + * virtio_mem_set_fake_offline() might sleep. We can safely + * drop the RCU lock at this point because the device + * cannot go away. See virtio_mem_remove() how races + * between memory onlining and device removal are handled. + */ + rcu_read_unlock(); + + virtio_mem_online_page(vm, page, order); + return; + } + rcu_read_unlock(); + + /* not virtio-mem memory, but e.g., a DIMM. online it */ + generic_online_page(page, order); +} + +static uint64_t virtio_mem_send_request(struct virtio_mem *vm, + const struct virtio_mem_req *req) +{ + struct scatterlist *sgs[2], sg_req, sg_resp; + unsigned int len; + int rc; + + /* don't use the request residing on the stack (vaddr) */ + vm->req = *req; + + /* out: buffer for request */ + sg_init_one(&sg_req, &vm->req, sizeof(vm->req)); + sgs[0] = &sg_req; + + /* in: buffer for response */ + sg_init_one(&sg_resp, &vm->resp, sizeof(vm->resp)); + sgs[1] = &sg_resp; + + rc = virtqueue_add_sgs(vm->vq, sgs, 1, 1, vm, GFP_KERNEL); + if (rc < 0) + return rc; + + virtqueue_kick(vm->vq); + + /* wait for a response */ + wait_event(vm->host_resp, virtqueue_get_buf(vm->vq, &len)); + + return virtio16_to_cpu(vm->vdev, vm->resp.type); +} + +static int virtio_mem_send_plug_request(struct virtio_mem *vm, uint64_t addr, + uint64_t size) +{ + const uint64_t nb_vm_blocks = size / vm->device_block_size; + const struct virtio_mem_req req = { + .type = cpu_to_virtio16(vm->vdev, VIRTIO_MEM_REQ_PLUG), + .u.plug.addr = cpu_to_virtio64(vm->vdev, addr), + .u.plug.nb_blocks = cpu_to_virtio16(vm->vdev, nb_vm_blocks), + }; + int rc = -ENOMEM; + + if (atomic_read(&vm->config_changed)) + return -EAGAIN; + + dev_dbg(&vm->vdev->dev, "plugging memory: 0x%llx - 0x%llx\n", addr, + addr + size - 1); + + switch (virtio_mem_send_request(vm, &req)) { + case VIRTIO_MEM_RESP_ACK: + vm->plugged_size += size; + return 0; + case VIRTIO_MEM_RESP_NACK: + rc = -EAGAIN; + break; + case VIRTIO_MEM_RESP_BUSY: + rc = -ETXTBSY; + break; + case VIRTIO_MEM_RESP_ERROR: + rc = -EINVAL; + break; + default: + break; + } + + dev_dbg(&vm->vdev->dev, "plugging memory failed: %d\n", rc); + return rc; +} + +static int virtio_mem_send_unplug_request(struct virtio_mem *vm, uint64_t addr, + uint64_t size) +{ + const uint64_t nb_vm_blocks = size / vm->device_block_size; + const struct virtio_mem_req req = { + .type = cpu_to_virtio16(vm->vdev, VIRTIO_MEM_REQ_UNPLUG), + .u.unplug.addr = cpu_to_virtio64(vm->vdev, addr), + .u.unplug.nb_blocks = cpu_to_virtio16(vm->vdev, nb_vm_blocks), + }; + int rc = -ENOMEM; + + if (atomic_read(&vm->config_changed)) + return -EAGAIN; + + dev_dbg(&vm->vdev->dev, "unplugging memory: 0x%llx - 0x%llx\n", addr, + addr + size - 1); + + switch (virtio_mem_send_request(vm, &req)) { + case VIRTIO_MEM_RESP_ACK: + vm->plugged_size -= size; + return 0; + case VIRTIO_MEM_RESP_BUSY: + rc = -ETXTBSY; + break; + case VIRTIO_MEM_RESP_ERROR: + rc = -EINVAL; + break; + default: + break; + } + + dev_dbg(&vm->vdev->dev, "unplugging memory failed: %d\n", rc); + return rc; +} + +static int virtio_mem_send_unplug_all_request(struct virtio_mem *vm) +{ + const struct virtio_mem_req req = { + .type = cpu_to_virtio16(vm->vdev, VIRTIO_MEM_REQ_UNPLUG_ALL), + }; + int rc = -ENOMEM; + + dev_dbg(&vm->vdev->dev, "unplugging all memory"); + + switch (virtio_mem_send_request(vm, &req)) { + case VIRTIO_MEM_RESP_ACK: + vm->unplug_all_required = false; + vm->plugged_size = 0; + /* usable region might have shrunk */ + atomic_set(&vm->config_changed, 1); + return 0; + case VIRTIO_MEM_RESP_BUSY: + rc = -ETXTBSY; + break; + default: + break; + } + + dev_dbg(&vm->vdev->dev, "unplugging all memory failed: %d\n", rc); + return rc; +} + +/* + * Plug selected subblocks. Updates the plugged state, but not the state + * of the memory block. + */ +static int virtio_mem_sbm_plug_sb(struct virtio_mem *vm, unsigned long mb_id, + int sb_id, int count) +{ + const uint64_t addr = virtio_mem_mb_id_to_phys(mb_id) + + sb_id * vm->sbm.sb_size; + const uint64_t size = count * vm->sbm.sb_size; + int rc; + + rc = virtio_mem_send_plug_request(vm, addr, size); + if (!rc) + virtio_mem_sbm_set_sb_plugged(vm, mb_id, sb_id, count); + return rc; +} + +/* + * Unplug selected subblocks. Updates the plugged state, but not the state + * of the memory block. + */ +static int virtio_mem_sbm_unplug_sb(struct virtio_mem *vm, unsigned long mb_id, + int sb_id, int count) +{ + const uint64_t addr = virtio_mem_mb_id_to_phys(mb_id) + + sb_id * vm->sbm.sb_size; + const uint64_t size = count * vm->sbm.sb_size; + int rc; + + rc = virtio_mem_send_unplug_request(vm, addr, size); + if (!rc) + virtio_mem_sbm_set_sb_unplugged(vm, mb_id, sb_id, count); + return rc; +} + +/* + * Request to unplug a big block. + * + * Will not modify the state of the big block. + */ +static int virtio_mem_bbm_unplug_bb(struct virtio_mem *vm, unsigned long bb_id) +{ + const uint64_t addr = virtio_mem_bb_id_to_phys(vm, bb_id); + const uint64_t size = vm->bbm.bb_size; + + return virtio_mem_send_unplug_request(vm, addr, size); +} + +/* + * Request to plug a big block. + * + * Will not modify the state of the big block. + */ +static int virtio_mem_bbm_plug_bb(struct virtio_mem *vm, unsigned long bb_id) +{ + const uint64_t addr = virtio_mem_bb_id_to_phys(vm, bb_id); + const uint64_t size = vm->bbm.bb_size; + + return virtio_mem_send_plug_request(vm, addr, size); +} + +/* + * Unplug the desired number of plugged subblocks of a offline or not-added + * memory block. Will fail if any subblock cannot get unplugged (instead of + * skipping it). + * + * Will not modify the state of the memory block. + * + * Note: can fail after some subblocks were unplugged. + */ +static int virtio_mem_sbm_unplug_any_sb_raw(struct virtio_mem *vm, + unsigned long mb_id, uint64_t *nb_sb) +{ + int sb_id, count; + int rc; + + sb_id = vm->sbm.sbs_per_mb - 1; + while (*nb_sb) { + /* Find the next candidate subblock */ + while (sb_id >= 0 && + virtio_mem_sbm_test_sb_unplugged(vm, mb_id, sb_id, 1)) + sb_id--; + if (sb_id < 0) + break; + /* Try to unplug multiple subblocks at a time */ + count = 1; + while (count < *nb_sb && sb_id > 0 && + virtio_mem_sbm_test_sb_plugged(vm, mb_id, sb_id - 1, 1)) { + count++; + sb_id--; + } + + rc = virtio_mem_sbm_unplug_sb(vm, mb_id, sb_id, count); + if (rc) + return rc; + *nb_sb -= count; + sb_id--; + } + + return 0; +} + +/* + * Unplug all plugged subblocks of an offline or not-added memory block. + * + * Will not modify the state of the memory block. + * + * Note: can fail after some subblocks were unplugged. + */ +static int virtio_mem_sbm_unplug_mb(struct virtio_mem *vm, unsigned long mb_id) +{ + uint64_t nb_sb = vm->sbm.sbs_per_mb; + + return virtio_mem_sbm_unplug_any_sb_raw(vm, mb_id, &nb_sb); +} + +/* + * Prepare tracking data for the next memory block. + */ +static int virtio_mem_sbm_prepare_next_mb(struct virtio_mem *vm, + unsigned long *mb_id) +{ + int rc; + + if (vm->sbm.next_mb_id > vm->sbm.last_usable_mb_id) + return -ENOSPC; + + /* Resize the state array if required. */ + rc = virtio_mem_sbm_mb_states_prepare_next_mb(vm); + if (rc) + return rc; + + /* Resize the subblock bitmap if required. */ + rc = virtio_mem_sbm_sb_states_prepare_next_mb(vm); + if (rc) + return rc; + + vm->sbm.mb_count[VIRTIO_MEM_SBM_MB_UNUSED]++; + *mb_id = vm->sbm.next_mb_id++; + return 0; +} + +/* + * Try to plug the desired number of subblocks and add the memory block + * to Linux. + * + * Will modify the state of the memory block. + */ +static int virtio_mem_sbm_plug_and_add_mb(struct virtio_mem *vm, + unsigned long mb_id, uint64_t *nb_sb) +{ + const int count = min_t(int, *nb_sb, vm->sbm.sbs_per_mb); + int rc; + + if (WARN_ON_ONCE(!count)) + return -EINVAL; + + /* + * Plug the requested number of subblocks before adding it to linux, + * so that onlining will directly online all plugged subblocks. + */ + rc = virtio_mem_sbm_plug_sb(vm, mb_id, 0, count); + if (rc) + return rc; + + /* + * Mark the block properly offline before adding it to Linux, + * so the memory notifiers will find the block in the right state. + */ + if (count == vm->sbm.sbs_per_mb) + virtio_mem_sbm_set_mb_state(vm, mb_id, + VIRTIO_MEM_SBM_MB_OFFLINE); + else + virtio_mem_sbm_set_mb_state(vm, mb_id, + VIRTIO_MEM_SBM_MB_OFFLINE_PARTIAL); + + /* Add the memory block to linux - if that fails, try to unplug. */ + rc = virtio_mem_sbm_add_mb(vm, mb_id); + if (rc) { + int new_state = VIRTIO_MEM_SBM_MB_UNUSED; + + if (virtio_mem_sbm_unplug_sb(vm, mb_id, 0, count)) + new_state = VIRTIO_MEM_SBM_MB_PLUGGED; + virtio_mem_sbm_set_mb_state(vm, mb_id, new_state); + return rc; + } + + *nb_sb -= count; + return 0; +} + +/* + * Try to plug the desired number of subblocks of a memory block that + * is already added to Linux. + * + * Will modify the state of the memory block. + * + * Note: Can fail after some subblocks were successfully plugged. + */ +static int virtio_mem_sbm_plug_any_sb(struct virtio_mem *vm, + unsigned long mb_id, uint64_t *nb_sb) +{ + const int old_state = virtio_mem_sbm_get_mb_state(vm, mb_id); + unsigned long pfn, nr_pages; + int sb_id, count; + int rc; + + if (WARN_ON_ONCE(!*nb_sb)) + return -EINVAL; + + while (*nb_sb) { + sb_id = virtio_mem_sbm_first_unplugged_sb(vm, mb_id); + if (sb_id >= vm->sbm.sbs_per_mb) + break; + count = 1; + while (count < *nb_sb && + sb_id + count < vm->sbm.sbs_per_mb && + !virtio_mem_sbm_test_sb_plugged(vm, mb_id, sb_id + count, 1)) + count++; + + rc = virtio_mem_sbm_plug_sb(vm, mb_id, sb_id, count); + if (rc) + return rc; + *nb_sb -= count; + if (old_state == VIRTIO_MEM_SBM_MB_OFFLINE_PARTIAL) + continue; + + /* fake-online the pages if the memory block is online */ + pfn = PFN_DOWN(virtio_mem_mb_id_to_phys(mb_id) + + sb_id * vm->sbm.sb_size); + nr_pages = PFN_DOWN(count * vm->sbm.sb_size); + virtio_mem_fake_online(pfn, nr_pages); + } + + if (virtio_mem_sbm_test_sb_plugged(vm, mb_id, 0, vm->sbm.sbs_per_mb)) + virtio_mem_sbm_set_mb_state(vm, mb_id, old_state - 1); + + return 0; +} + +static int virtio_mem_sbm_plug_request(struct virtio_mem *vm, uint64_t diff) +{ + const int mb_states[] = { + VIRTIO_MEM_SBM_MB_KERNEL_PARTIAL, + VIRTIO_MEM_SBM_MB_MOVABLE_PARTIAL, + VIRTIO_MEM_SBM_MB_OFFLINE_PARTIAL, + }; + uint64_t nb_sb = diff / vm->sbm.sb_size; + unsigned long mb_id; + int rc, i; + + if (!nb_sb) + return 0; + + /* Don't race with onlining/offlining */ + mutex_lock(&vm->hotplug_mutex); + + for (i = 0; i < ARRAY_SIZE(mb_states); i++) { + virtio_mem_sbm_for_each_mb(vm, mb_id, mb_states[i]) { + rc = virtio_mem_sbm_plug_any_sb(vm, mb_id, &nb_sb); + if (rc || !nb_sb) + goto out_unlock; + cond_resched(); + } + } + + /* + * We won't be working on online/offline memory blocks from this point, + * so we can't race with memory onlining/offlining. Drop the mutex. + */ + mutex_unlock(&vm->hotplug_mutex); + + /* Try to plug and add unused blocks */ + virtio_mem_sbm_for_each_mb(vm, mb_id, VIRTIO_MEM_SBM_MB_UNUSED) { + if (!virtio_mem_could_add_memory(vm, memory_block_size_bytes())) + return -ENOSPC; + + rc = virtio_mem_sbm_plug_and_add_mb(vm, mb_id, &nb_sb); + if (rc || !nb_sb) + return rc; + cond_resched(); + } + + /* Try to prepare, plug and add new blocks */ + while (nb_sb) { + if (!virtio_mem_could_add_memory(vm, memory_block_size_bytes())) + return -ENOSPC; + + rc = virtio_mem_sbm_prepare_next_mb(vm, &mb_id); + if (rc) + return rc; + rc = virtio_mem_sbm_plug_and_add_mb(vm, mb_id, &nb_sb); + if (rc) + return rc; + cond_resched(); + } + + return 0; +out_unlock: + mutex_unlock(&vm->hotplug_mutex); + return rc; +} + +/* + * Plug a big block and add it to Linux. + * + * Will modify the state of the big block. + */ +static int virtio_mem_bbm_plug_and_add_bb(struct virtio_mem *vm, + unsigned long bb_id) +{ + int rc; + + if (WARN_ON_ONCE(virtio_mem_bbm_get_bb_state(vm, bb_id) != + VIRTIO_MEM_BBM_BB_UNUSED)) + return -EINVAL; + + rc = virtio_mem_bbm_plug_bb(vm, bb_id); + if (rc) + return rc; + virtio_mem_bbm_set_bb_state(vm, bb_id, VIRTIO_MEM_BBM_BB_ADDED); + + rc = virtio_mem_bbm_add_bb(vm, bb_id); + if (rc) { + if (!virtio_mem_bbm_unplug_bb(vm, bb_id)) + virtio_mem_bbm_set_bb_state(vm, bb_id, + VIRTIO_MEM_BBM_BB_UNUSED); + else + /* Retry from the main loop. */ + virtio_mem_bbm_set_bb_state(vm, bb_id, + VIRTIO_MEM_BBM_BB_PLUGGED); + return rc; + } + return 0; +} + +/* + * Prepare tracking data for the next big block. + */ +static int virtio_mem_bbm_prepare_next_bb(struct virtio_mem *vm, + unsigned long *bb_id) +{ + int rc; + + if (vm->bbm.next_bb_id > vm->bbm.last_usable_bb_id) + return -ENOSPC; + + /* Resize the big block state array if required. */ + rc = virtio_mem_bbm_bb_states_prepare_next_bb(vm); + if (rc) + return rc; + + vm->bbm.bb_count[VIRTIO_MEM_BBM_BB_UNUSED]++; + *bb_id = vm->bbm.next_bb_id; + vm->bbm.next_bb_id++; + return 0; +} + +static int virtio_mem_bbm_plug_request(struct virtio_mem *vm, uint64_t diff) +{ + uint64_t nb_bb = diff / vm->bbm.bb_size; + unsigned long bb_id; + int rc; + + if (!nb_bb) + return 0; + + /* Try to plug and add unused big blocks */ + virtio_mem_bbm_for_each_bb(vm, bb_id, VIRTIO_MEM_BBM_BB_UNUSED) { + if (!virtio_mem_could_add_memory(vm, vm->bbm.bb_size)) + return -ENOSPC; + + rc = virtio_mem_bbm_plug_and_add_bb(vm, bb_id); + if (!rc) + nb_bb--; + if (rc || !nb_bb) + return rc; + cond_resched(); + } + + /* Try to prepare, plug and add new big blocks */ + while (nb_bb) { + if (!virtio_mem_could_add_memory(vm, vm->bbm.bb_size)) + return -ENOSPC; + + rc = virtio_mem_bbm_prepare_next_bb(vm, &bb_id); + if (rc) + return rc; + rc = virtio_mem_bbm_plug_and_add_bb(vm, bb_id); + if (!rc) + nb_bb--; + if (rc) + return rc; + cond_resched(); + } + + return 0; +} + +/* + * Try to plug the requested amount of memory. + */ +static int virtio_mem_plug_request(struct virtio_mem *vm, uint64_t diff) +{ + if (vm->in_sbm) + return virtio_mem_sbm_plug_request(vm, diff); + return virtio_mem_bbm_plug_request(vm, diff); +} + +/* + * Unplug the desired number of plugged subblocks of an offline memory block. + * Will fail if any subblock cannot get unplugged (instead of skipping it). + * + * Will modify the state of the memory block. Might temporarily drop the + * hotplug_mutex. + * + * Note: Can fail after some subblocks were successfully unplugged. + */ +static int virtio_mem_sbm_unplug_any_sb_offline(struct virtio_mem *vm, + unsigned long mb_id, + uint64_t *nb_sb) +{ + int rc; + + rc = virtio_mem_sbm_unplug_any_sb_raw(vm, mb_id, nb_sb); + + /* some subblocks might have been unplugged even on failure */ + if (!virtio_mem_sbm_test_sb_plugged(vm, mb_id, 0, vm->sbm.sbs_per_mb)) + virtio_mem_sbm_set_mb_state(vm, mb_id, + VIRTIO_MEM_SBM_MB_OFFLINE_PARTIAL); + if (rc) + return rc; + + if (virtio_mem_sbm_test_sb_unplugged(vm, mb_id, 0, vm->sbm.sbs_per_mb)) { + /* + * Remove the block from Linux - this should never fail. + * Hinder the block from getting onlined by marking it + * unplugged. Temporarily drop the mutex, so + * any pending GOING_ONLINE requests can be serviced/rejected. + */ + virtio_mem_sbm_set_mb_state(vm, mb_id, + VIRTIO_MEM_SBM_MB_UNUSED); + + mutex_unlock(&vm->hotplug_mutex); + rc = virtio_mem_sbm_remove_mb(vm, mb_id); + BUG_ON(rc); + mutex_lock(&vm->hotplug_mutex); + } + return 0; +} + +/* + * Unplug the given plugged subblocks of an online memory block. + * + * Will modify the state of the memory block. + */ +static int virtio_mem_sbm_unplug_sb_online(struct virtio_mem *vm, + unsigned long mb_id, int sb_id, + int count) +{ + const unsigned long nr_pages = PFN_DOWN(vm->sbm.sb_size) * count; + const int old_state = virtio_mem_sbm_get_mb_state(vm, mb_id); + unsigned long start_pfn; + int rc; + + start_pfn = PFN_DOWN(virtio_mem_mb_id_to_phys(mb_id) + + sb_id * vm->sbm.sb_size); + + rc = virtio_mem_fake_offline(vm, start_pfn, nr_pages); + if (rc) + return rc; + + /* Try to unplug the allocated memory */ + rc = virtio_mem_sbm_unplug_sb(vm, mb_id, sb_id, count); + if (rc) { + /* Return the memory to the buddy. */ + virtio_mem_fake_online(start_pfn, nr_pages); + return rc; + } + + switch (old_state) { + case VIRTIO_MEM_SBM_MB_KERNEL: + virtio_mem_sbm_set_mb_state(vm, mb_id, + VIRTIO_MEM_SBM_MB_KERNEL_PARTIAL); + break; + case VIRTIO_MEM_SBM_MB_MOVABLE: + virtio_mem_sbm_set_mb_state(vm, mb_id, + VIRTIO_MEM_SBM_MB_MOVABLE_PARTIAL); + break; + } + + return 0; +} + +/* + * Unplug the desired number of plugged subblocks of an online memory block. + * Will skip subblock that are busy. + * + * Will modify the state of the memory block. Might temporarily drop the + * hotplug_mutex. + * + * Note: Can fail after some subblocks were successfully unplugged. Can + * return 0 even if subblocks were busy and could not get unplugged. + */ +static int virtio_mem_sbm_unplug_any_sb_online(struct virtio_mem *vm, + unsigned long mb_id, + uint64_t *nb_sb) +{ + int rc, sb_id; + + /* If possible, try to unplug the complete block in one shot. */ + if (*nb_sb >= vm->sbm.sbs_per_mb && + virtio_mem_sbm_test_sb_plugged(vm, mb_id, 0, vm->sbm.sbs_per_mb)) { + rc = virtio_mem_sbm_unplug_sb_online(vm, mb_id, 0, + vm->sbm.sbs_per_mb); + if (!rc) { + *nb_sb -= vm->sbm.sbs_per_mb; + goto unplugged; + } else if (rc != -EBUSY) + return rc; + } + + /* Fallback to single subblocks. */ + for (sb_id = vm->sbm.sbs_per_mb - 1; sb_id >= 0 && *nb_sb; sb_id--) { + /* Find the next candidate subblock */ + while (sb_id >= 0 && + !virtio_mem_sbm_test_sb_plugged(vm, mb_id, sb_id, 1)) + sb_id--; + if (sb_id < 0) + break; + + rc = virtio_mem_sbm_unplug_sb_online(vm, mb_id, sb_id, 1); + if (rc == -EBUSY) + continue; + else if (rc) + return rc; + *nb_sb -= 1; + } + +unplugged: + rc = virtio_mem_sbm_try_remove_unplugged_mb(vm, mb_id); + if (rc) + vm->sbm.have_unplugged_mb = 1; + /* Ignore errors, this is not critical. We'll retry later. */ + return 0; +} + +/* + * Unplug the desired number of plugged subblocks of a memory block that is + * already added to Linux. Will skip subblock of online memory blocks that are + * busy (by the OS). Will fail if any subblock that's not busy cannot get + * unplugged. + * + * Will modify the state of the memory block. Might temporarily drop the + * hotplug_mutex. + * + * Note: Can fail after some subblocks were successfully unplugged. Can + * return 0 even if subblocks were busy and could not get unplugged. + */ +static int virtio_mem_sbm_unplug_any_sb(struct virtio_mem *vm, + unsigned long mb_id, + uint64_t *nb_sb) +{ + const int old_state = virtio_mem_sbm_get_mb_state(vm, mb_id); + + switch (old_state) { + case VIRTIO_MEM_SBM_MB_KERNEL_PARTIAL: + case VIRTIO_MEM_SBM_MB_KERNEL: + case VIRTIO_MEM_SBM_MB_MOVABLE_PARTIAL: + case VIRTIO_MEM_SBM_MB_MOVABLE: + return virtio_mem_sbm_unplug_any_sb_online(vm, mb_id, nb_sb); + case VIRTIO_MEM_SBM_MB_OFFLINE_PARTIAL: + case VIRTIO_MEM_SBM_MB_OFFLINE: + return virtio_mem_sbm_unplug_any_sb_offline(vm, mb_id, nb_sb); + } + return -EINVAL; +} + +static int virtio_mem_sbm_unplug_request(struct virtio_mem *vm, uint64_t diff) +{ + const int mb_states[] = { + VIRTIO_MEM_SBM_MB_OFFLINE_PARTIAL, + VIRTIO_MEM_SBM_MB_OFFLINE, + VIRTIO_MEM_SBM_MB_MOVABLE_PARTIAL, + VIRTIO_MEM_SBM_MB_KERNEL_PARTIAL, + VIRTIO_MEM_SBM_MB_MOVABLE, + VIRTIO_MEM_SBM_MB_KERNEL, + }; + uint64_t nb_sb = diff / vm->sbm.sb_size; + unsigned long mb_id; + int rc, i; + + if (!nb_sb) + return 0; + + /* + * We'll drop the mutex a couple of times when it is safe to do so. + * This might result in some blocks switching the state (online/offline) + * and we could miss them in this run - we will retry again later. + */ + mutex_lock(&vm->hotplug_mutex); + + /* + * We try unplug from partially plugged blocks first, to try removing + * whole memory blocks along with metadata. We prioritize ZONE_MOVABLE + * as it's more reliable to unplug memory and remove whole memory + * blocks, and we don't want to trigger a zone imbalances by + * accidentially removing too much kernel memory. + */ + for (i = 0; i < ARRAY_SIZE(mb_states); i++) { + virtio_mem_sbm_for_each_mb_rev(vm, mb_id, mb_states[i]) { + rc = virtio_mem_sbm_unplug_any_sb(vm, mb_id, &nb_sb); + if (rc || !nb_sb) + goto out_unlock; + mutex_unlock(&vm->hotplug_mutex); + cond_resched(); + mutex_lock(&vm->hotplug_mutex); + } + if (!unplug_online && i == 1) { + mutex_unlock(&vm->hotplug_mutex); + return 0; + } + } + + mutex_unlock(&vm->hotplug_mutex); + return nb_sb ? -EBUSY : 0; +out_unlock: + mutex_unlock(&vm->hotplug_mutex); + return rc; +} + +/* + * Try to offline and remove a big block from Linux and unplug it. Will fail + * with -EBUSY if some memory is busy and cannot get unplugged. + * + * Will modify the state of the memory block. Might temporarily drop the + * hotplug_mutex. + */ +static int virtio_mem_bbm_offline_remove_and_unplug_bb(struct virtio_mem *vm, + unsigned long bb_id) +{ + const unsigned long start_pfn = PFN_DOWN(virtio_mem_bb_id_to_phys(vm, bb_id)); + const unsigned long nr_pages = PFN_DOWN(vm->bbm.bb_size); + unsigned long end_pfn = start_pfn + nr_pages; + unsigned long pfn; + struct page *page; + int rc; + + if (WARN_ON_ONCE(virtio_mem_bbm_get_bb_state(vm, bb_id) != + VIRTIO_MEM_BBM_BB_ADDED)) + return -EINVAL; + + /* + * Start by fake-offlining all memory. Once we marked the device + * block as fake-offline, all newly onlined memory will + * automatically be kept fake-offline. Protect from concurrent + * onlining/offlining until we have a consistent state. + */ + mutex_lock(&vm->hotplug_mutex); + virtio_mem_bbm_set_bb_state(vm, bb_id, VIRTIO_MEM_BBM_BB_FAKE_OFFLINE); + + for (pfn = start_pfn; pfn < end_pfn; pfn += PAGES_PER_SECTION) { + page = pfn_to_online_page(pfn); + if (!page) + continue; + + rc = virtio_mem_fake_offline(vm, pfn, PAGES_PER_SECTION); + if (rc) { + end_pfn = pfn; + goto rollback; + } + } + mutex_unlock(&vm->hotplug_mutex); + + rc = virtio_mem_bbm_offline_and_remove_bb(vm, bb_id); + if (rc) { + mutex_lock(&vm->hotplug_mutex); + goto rollback; + } + + rc = virtio_mem_bbm_unplug_bb(vm, bb_id); + if (rc) + virtio_mem_bbm_set_bb_state(vm, bb_id, + VIRTIO_MEM_BBM_BB_PLUGGED); + else + virtio_mem_bbm_set_bb_state(vm, bb_id, + VIRTIO_MEM_BBM_BB_UNUSED); + return rc; + +rollback: + for (pfn = start_pfn; pfn < end_pfn; pfn += PAGES_PER_SECTION) { + page = pfn_to_online_page(pfn); + if (!page) + continue; + virtio_mem_fake_online(pfn, PAGES_PER_SECTION); + } + virtio_mem_bbm_set_bb_state(vm, bb_id, VIRTIO_MEM_BBM_BB_ADDED); + mutex_unlock(&vm->hotplug_mutex); + return rc; +} + +/* + * Test if a big block is completely offline. + */ +static bool virtio_mem_bbm_bb_is_offline(struct virtio_mem *vm, + unsigned long bb_id) +{ + const unsigned long start_pfn = PFN_DOWN(virtio_mem_bb_id_to_phys(vm, bb_id)); + const unsigned long nr_pages = PFN_DOWN(vm->bbm.bb_size); + unsigned long pfn; + + for (pfn = start_pfn; pfn < start_pfn + nr_pages; + pfn += PAGES_PER_SECTION) { + if (pfn_to_online_page(pfn)) + return false; + } + + return true; +} + +/* + * Test if a big block is completely onlined to ZONE_MOVABLE (or offline). + */ +static bool virtio_mem_bbm_bb_is_movable(struct virtio_mem *vm, + unsigned long bb_id) +{ + const unsigned long start_pfn = PFN_DOWN(virtio_mem_bb_id_to_phys(vm, bb_id)); + const unsigned long nr_pages = PFN_DOWN(vm->bbm.bb_size); + struct page *page; + unsigned long pfn; + + for (pfn = start_pfn; pfn < start_pfn + nr_pages; + pfn += PAGES_PER_SECTION) { + page = pfn_to_online_page(pfn); + if (!page) + continue; + if (page_zonenum(page) != ZONE_MOVABLE) + return false; + } + + return true; +} + +static int virtio_mem_bbm_unplug_request(struct virtio_mem *vm, uint64_t diff) +{ + uint64_t nb_bb = diff / vm->bbm.bb_size; + uint64_t bb_id; + int rc, i; + + if (!nb_bb) + return 0; + + /* + * Try to unplug big blocks. Similar to SBM, start with offline + * big blocks. + */ + for (i = 0; i < 3; i++) { + virtio_mem_bbm_for_each_bb_rev(vm, bb_id, VIRTIO_MEM_BBM_BB_ADDED) { + cond_resched(); + + /* + * As we're holding no locks, these checks are racy, + * but we don't care. + */ + if (i == 0 && !virtio_mem_bbm_bb_is_offline(vm, bb_id)) + continue; + if (i == 1 && !virtio_mem_bbm_bb_is_movable(vm, bb_id)) + continue; + rc = virtio_mem_bbm_offline_remove_and_unplug_bb(vm, bb_id); + if (rc == -EBUSY) + continue; + if (!rc) + nb_bb--; + if (rc || !nb_bb) + return rc; + } + if (i == 0 && !unplug_online) + return 0; + } + + return nb_bb ? -EBUSY : 0; +} + +/* + * Try to unplug the requested amount of memory. + */ +static int virtio_mem_unplug_request(struct virtio_mem *vm, uint64_t diff) +{ + if (vm->in_sbm) + return virtio_mem_sbm_unplug_request(vm, diff); + return virtio_mem_bbm_unplug_request(vm, diff); +} + +/* + * Try to unplug all blocks that couldn't be unplugged before, for example, + * because the hypervisor was busy. Further, offline and remove any memory + * blocks where we previously failed. + */ +static int virtio_mem_cleanup_pending_mb(struct virtio_mem *vm) +{ + unsigned long id; + int rc = 0; + + if (!vm->in_sbm) { + virtio_mem_bbm_for_each_bb(vm, id, + VIRTIO_MEM_BBM_BB_PLUGGED) { + rc = virtio_mem_bbm_unplug_bb(vm, id); + if (rc) + return rc; + virtio_mem_bbm_set_bb_state(vm, id, + VIRTIO_MEM_BBM_BB_UNUSED); + } + return 0; + } + + virtio_mem_sbm_for_each_mb(vm, id, VIRTIO_MEM_SBM_MB_PLUGGED) { + rc = virtio_mem_sbm_unplug_mb(vm, id); + if (rc) + return rc; + virtio_mem_sbm_set_mb_state(vm, id, + VIRTIO_MEM_SBM_MB_UNUSED); + } + + if (!vm->sbm.have_unplugged_mb) + return 0; + + /* + * Let's retry (offlining and) removing completely unplugged Linux + * memory blocks. + */ + vm->sbm.have_unplugged_mb = false; + + mutex_lock(&vm->hotplug_mutex); + virtio_mem_sbm_for_each_mb(vm, id, VIRTIO_MEM_SBM_MB_MOVABLE_PARTIAL) + rc |= virtio_mem_sbm_try_remove_unplugged_mb(vm, id); + virtio_mem_sbm_for_each_mb(vm, id, VIRTIO_MEM_SBM_MB_KERNEL_PARTIAL) + rc |= virtio_mem_sbm_try_remove_unplugged_mb(vm, id); + virtio_mem_sbm_for_each_mb(vm, id, VIRTIO_MEM_SBM_MB_OFFLINE_PARTIAL) + rc |= virtio_mem_sbm_try_remove_unplugged_mb(vm, id); + mutex_unlock(&vm->hotplug_mutex); + + if (rc) + vm->sbm.have_unplugged_mb = true; + /* Ignore errors, this is not critical. We'll retry later. */ + return 0; +} + +/* + * Update all parts of the config that could have changed. + */ +static void virtio_mem_refresh_config(struct virtio_mem *vm) +{ + const struct range pluggable_range = mhp_get_pluggable_range(true); + uint64_t new_plugged_size, end_addr; + + /* the plugged_size is just a reflection of what _we_ did previously */ + virtio_cread_le(vm->vdev, struct virtio_mem_config, plugged_size, + &new_plugged_size); + if (WARN_ON_ONCE(new_plugged_size != vm->plugged_size)) + vm->plugged_size = new_plugged_size; + + /* calculate the last usable memory block id */ + virtio_cread_le(vm->vdev, struct virtio_mem_config, + usable_region_size, &vm->usable_region_size); + end_addr = min(vm->addr + vm->usable_region_size - 1, + pluggable_range.end); + + if (vm->in_sbm) { + vm->sbm.last_usable_mb_id = virtio_mem_phys_to_mb_id(end_addr); + if (!IS_ALIGNED(end_addr + 1, memory_block_size_bytes())) + vm->sbm.last_usable_mb_id--; + } else { + vm->bbm.last_usable_bb_id = virtio_mem_phys_to_bb_id(vm, + end_addr); + if (!IS_ALIGNED(end_addr + 1, vm->bbm.bb_size)) + vm->bbm.last_usable_bb_id--; + } + /* + * If we cannot plug any of our device memory (e.g., nothing in the + * usable region is addressable), the last usable memory block id will + * be smaller than the first usable memory block id. We'll stop + * attempting to add memory with -ENOSPC from our main loop. + */ + + /* see if there is a request to change the size */ + virtio_cread_le(vm->vdev, struct virtio_mem_config, requested_size, + &vm->requested_size); + + dev_info(&vm->vdev->dev, "plugged size: 0x%llx", vm->plugged_size); + dev_info(&vm->vdev->dev, "requested size: 0x%llx", vm->requested_size); +} + +/* + * Workqueue function for handling plug/unplug requests and config updates. + */ +static void virtio_mem_run_wq(struct work_struct *work) +{ + struct virtio_mem *vm = container_of(work, struct virtio_mem, wq); + uint64_t diff; + int rc; + + if (unlikely(vm->in_kdump)) { + dev_warn_once(&vm->vdev->dev, + "unexpected workqueue run in kdump kernel\n"); + return; + } + + hrtimer_cancel(&vm->retry_timer); + + if (vm->broken) + return; + + atomic_set(&vm->wq_active, 1); +retry: + rc = 0; + + /* Make sure we start with a clean state if there are leftovers. */ + if (unlikely(vm->unplug_all_required)) + rc = virtio_mem_send_unplug_all_request(vm); + + if (atomic_read(&vm->config_changed)) { + atomic_set(&vm->config_changed, 0); + virtio_mem_refresh_config(vm); + } + + /* Cleanup any leftovers from previous runs */ + if (!rc) + rc = virtio_mem_cleanup_pending_mb(vm); + + if (!rc && vm->requested_size != vm->plugged_size) { + if (vm->requested_size > vm->plugged_size) { + diff = vm->requested_size - vm->plugged_size; + rc = virtio_mem_plug_request(vm, diff); + } else { + diff = vm->plugged_size - vm->requested_size; + rc = virtio_mem_unplug_request(vm, diff); + } + } + + /* + * Keep retrying to offline and remove completely unplugged Linux + * memory blocks. + */ + if (!rc && vm->in_sbm && vm->sbm.have_unplugged_mb) + rc = -EBUSY; + + switch (rc) { + case 0: + vm->retry_timer_ms = VIRTIO_MEM_RETRY_TIMER_MIN_MS; + break; + case -ENOSPC: + /* + * We cannot add any more memory (alignment, physical limit) + * or we have too many offline memory blocks. + */ + break; + case -ETXTBSY: + /* + * The hypervisor cannot process our request right now + * (e.g., out of memory, migrating); + */ + case -EBUSY: + /* + * We cannot free up any memory to unplug it (all plugged memory + * is busy). + */ + case -ENOMEM: + /* Out of memory, try again later. */ + hrtimer_start(&vm->retry_timer, ms_to_ktime(vm->retry_timer_ms), + HRTIMER_MODE_REL); + break; + case -EAGAIN: + /* Retry immediately (e.g., the config changed). */ + goto retry; + default: + /* Unknown error, mark as broken */ + dev_err(&vm->vdev->dev, + "unknown error, marking device broken: %d\n", rc); + vm->broken = true; + } + + atomic_set(&vm->wq_active, 0); +} + +static enum hrtimer_restart virtio_mem_timer_expired(struct hrtimer *timer) +{ + struct virtio_mem *vm = container_of(timer, struct virtio_mem, + retry_timer); + + virtio_mem_retry(vm); + vm->retry_timer_ms = min_t(unsigned int, vm->retry_timer_ms * 2, + VIRTIO_MEM_RETRY_TIMER_MAX_MS); + return HRTIMER_NORESTART; +} + +static void virtio_mem_handle_response(struct virtqueue *vq) +{ + struct virtio_mem *vm = vq->vdev->priv; + + wake_up(&vm->host_resp); +} + +static int virtio_mem_init_vq(struct virtio_mem *vm) +{ + struct virtqueue *vq; + + vq = virtio_find_single_vq(vm->vdev, virtio_mem_handle_response, + "guest-request"); + if (IS_ERR(vq)) + return PTR_ERR(vq); + vm->vq = vq; + + return 0; +} + +static int virtio_mem_init_hotplug(struct virtio_mem *vm) +{ + const struct range pluggable_range = mhp_get_pluggable_range(true); + uint64_t unit_pages, sb_size, addr; + int rc; + + /* bad device setup - warn only */ + if (!IS_ALIGNED(vm->addr, memory_block_size_bytes())) + dev_warn(&vm->vdev->dev, + "The alignment of the physical start address can make some memory unusable.\n"); + if (!IS_ALIGNED(vm->addr + vm->region_size, memory_block_size_bytes())) + dev_warn(&vm->vdev->dev, + "The alignment of the physical end address can make some memory unusable.\n"); + if (vm->addr < pluggable_range.start || + vm->addr + vm->region_size - 1 > pluggable_range.end) + dev_warn(&vm->vdev->dev, + "Some device memory is not addressable/pluggable. This can make some memory unusable.\n"); + + /* Prepare the offline threshold - make sure we can add two blocks. */ + vm->offline_threshold = max_t(uint64_t, 2 * memory_block_size_bytes(), + VIRTIO_MEM_DEFAULT_OFFLINE_THRESHOLD); + + /* + * alloc_contig_range() works reliably with pageblock + * granularity on ZONE_NORMAL, use pageblock_nr_pages. + */ + sb_size = PAGE_SIZE * pageblock_nr_pages; + sb_size = max_t(uint64_t, vm->device_block_size, sb_size); + + if (sb_size < memory_block_size_bytes() && !force_bbm) { + /* SBM: At least two subblocks per Linux memory block. */ + vm->in_sbm = true; + vm->sbm.sb_size = sb_size; + vm->sbm.sbs_per_mb = memory_block_size_bytes() / + vm->sbm.sb_size; + + /* Round up to the next full memory block */ + addr = max_t(uint64_t, vm->addr, pluggable_range.start) + + memory_block_size_bytes() - 1; + vm->sbm.first_mb_id = virtio_mem_phys_to_mb_id(addr); + vm->sbm.next_mb_id = vm->sbm.first_mb_id; + } else { + /* BBM: At least one Linux memory block. */ + vm->bbm.bb_size = max_t(uint64_t, vm->device_block_size, + memory_block_size_bytes()); + + if (bbm_block_size) { + if (!is_power_of_2(bbm_block_size)) { + dev_warn(&vm->vdev->dev, + "bbm_block_size is not a power of 2"); + } else if (bbm_block_size < vm->bbm.bb_size) { + dev_warn(&vm->vdev->dev, + "bbm_block_size is too small"); + } else { + vm->bbm.bb_size = bbm_block_size; + } + } + + /* Round up to the next aligned big block */ + addr = max_t(uint64_t, vm->addr, pluggable_range.start) + + vm->bbm.bb_size - 1; + vm->bbm.first_bb_id = virtio_mem_phys_to_bb_id(vm, addr); + vm->bbm.next_bb_id = vm->bbm.first_bb_id; + + /* Make sure we can add two big blocks. */ + vm->offline_threshold = max_t(uint64_t, 2 * vm->bbm.bb_size, + vm->offline_threshold); + } + + dev_info(&vm->vdev->dev, "memory block size: 0x%lx", + memory_block_size_bytes()); + if (vm->in_sbm) + dev_info(&vm->vdev->dev, "subblock size: 0x%llx", + (unsigned long long)vm->sbm.sb_size); + else + dev_info(&vm->vdev->dev, "big block size: 0x%llx", + (unsigned long long)vm->bbm.bb_size); + + /* create the parent resource for all memory */ + rc = virtio_mem_create_resource(vm); + if (rc) + return rc; + + /* use a single dynamic memory group to cover the whole memory device */ + if (vm->in_sbm) + unit_pages = PHYS_PFN(memory_block_size_bytes()); + else + unit_pages = PHYS_PFN(vm->bbm.bb_size); + rc = memory_group_register_dynamic(vm->nid, unit_pages); + if (rc < 0) + goto out_del_resource; + vm->mgid = rc; + + /* + * If we still have memory plugged, we have to unplug all memory first. + * Registering our parent resource makes sure that this memory isn't + * actually in use (e.g., trying to reload the driver). + */ + if (vm->plugged_size) { + vm->unplug_all_required = true; + dev_info(&vm->vdev->dev, "unplugging all memory is required\n"); + } + + /* register callbacks */ + vm->memory_notifier.notifier_call = virtio_mem_memory_notifier_cb; + rc = register_memory_notifier(&vm->memory_notifier); + if (rc) + goto out_unreg_group; + /* Block hibernation as early as possible. */ + vm->pm_notifier.priority = INT_MAX; + vm->pm_notifier.notifier_call = virtio_mem_pm_notifier_cb; + rc = register_pm_notifier(&vm->pm_notifier); + if (rc) + goto out_unreg_mem; + rc = register_virtio_mem_device(vm); + if (rc) + goto out_unreg_pm; + + virtio_device_ready(vm->vdev); + return 0; +out_unreg_pm: + unregister_pm_notifier(&vm->pm_notifier); +out_unreg_mem: + unregister_memory_notifier(&vm->memory_notifier); +out_unreg_group: + memory_group_unregister(vm->mgid); +out_del_resource: + virtio_mem_delete_resource(vm); + return rc; +} + +#ifdef CONFIG_PROC_VMCORE +static int virtio_mem_send_state_request(struct virtio_mem *vm, uint64_t addr, + uint64_t size) +{ + const uint64_t nb_vm_blocks = size / vm->device_block_size; + const struct virtio_mem_req req = { + .type = cpu_to_virtio16(vm->vdev, VIRTIO_MEM_REQ_STATE), + .u.state.addr = cpu_to_virtio64(vm->vdev, addr), + .u.state.nb_blocks = cpu_to_virtio16(vm->vdev, nb_vm_blocks), + }; + int rc = -ENOMEM; + + dev_dbg(&vm->vdev->dev, "requesting state: 0x%llx - 0x%llx\n", addr, + addr + size - 1); + + switch (virtio_mem_send_request(vm, &req)) { + case VIRTIO_MEM_RESP_ACK: + return virtio16_to_cpu(vm->vdev, vm->resp.u.state.state); + case VIRTIO_MEM_RESP_ERROR: + rc = -EINVAL; + break; + default: + break; + } + + dev_dbg(&vm->vdev->dev, "requesting state failed: %d\n", rc); + return rc; +} + +static bool virtio_mem_vmcore_pfn_is_ram(struct vmcore_cb *cb, + unsigned long pfn) +{ + struct virtio_mem *vm = container_of(cb, struct virtio_mem, + vmcore_cb); + uint64_t addr = PFN_PHYS(pfn); + bool is_ram; + int rc; + + if (!virtio_mem_contains_range(vm, addr, PAGE_SIZE)) + return true; + if (!vm->plugged_size) + return false; + + /* + * We have to serialize device requests and access to the information + * about the block queried last. + */ + mutex_lock(&vm->hotplug_mutex); + + addr = ALIGN_DOWN(addr, vm->device_block_size); + if (addr != vm->last_block_addr) { + rc = virtio_mem_send_state_request(vm, addr, + vm->device_block_size); + /* On any kind of error, we're going to signal !ram. */ + if (rc == VIRTIO_MEM_STATE_PLUGGED) + vm->last_block_plugged = true; + else + vm->last_block_plugged = false; + vm->last_block_addr = addr; + } + + is_ram = vm->last_block_plugged; + mutex_unlock(&vm->hotplug_mutex); + return is_ram; +} + +#ifdef CONFIG_PROC_VMCORE_DEVICE_RAM +static int virtio_mem_vmcore_add_device_ram(struct virtio_mem *vm, + struct list_head *list, uint64_t start, uint64_t end) +{ + int rc; + + rc = vmcore_alloc_add_range(list, start, end - start); + if (rc) + dev_err(&vm->vdev->dev, + "Error adding device RAM range: %d\n", rc); + return rc; +} + +static int virtio_mem_vmcore_get_device_ram(struct vmcore_cb *cb, + struct list_head *list) +{ + struct virtio_mem *vm = container_of(cb, struct virtio_mem, + vmcore_cb); + const uint64_t device_start = vm->addr; + const uint64_t device_end = vm->addr + vm->usable_region_size; + uint64_t chunk_size, cur_start, cur_end, plugged_range_start = 0; + LIST_HEAD(tmp_list); + int rc; + + if (!vm->plugged_size) + return 0; + + /* Process memory sections, unless the device block size is bigger. */ + chunk_size = max_t(uint64_t, PFN_PHYS(PAGES_PER_SECTION), + vm->device_block_size); + + mutex_lock(&vm->hotplug_mutex); + + /* + * We process larger chunks and indicate the complete chunk if any + * block in there is plugged. This reduces the number of pfn_is_ram() + * callbacks and mimic what is effectively being done when the old + * kernel would add complete memory sections/blocks to the elfcore hdr. + */ + cur_start = device_start; + for (cur_start = device_start; cur_start < device_end; cur_start = cur_end) { + cur_end = ALIGN_DOWN(cur_start + chunk_size, chunk_size); + cur_end = min_t(uint64_t, cur_end, device_end); + + rc = virtio_mem_send_state_request(vm, cur_start, + cur_end - cur_start); + + if (rc < 0) { + dev_err(&vm->vdev->dev, + "Error querying block states: %d\n", rc); + goto out; + } else if (rc != VIRTIO_MEM_STATE_UNPLUGGED) { + /* Merge ranges with plugged memory. */ + if (!plugged_range_start) + plugged_range_start = cur_start; + continue; + } + + /* Flush any plugged range. */ + if (plugged_range_start) { + rc = virtio_mem_vmcore_add_device_ram(vm, &tmp_list, + plugged_range_start, + cur_start); + if (rc) + goto out; + plugged_range_start = 0; + } + } + + /* Flush any plugged range. */ + if (plugged_range_start) + rc = virtio_mem_vmcore_add_device_ram(vm, &tmp_list, + plugged_range_start, + cur_start); +out: + mutex_unlock(&vm->hotplug_mutex); + if (rc < 0) { + vmcore_free_ranges(&tmp_list); + return rc; + } + list_splice_tail(&tmp_list, list); + return 0; +} +#endif /* CONFIG_PROC_VMCORE_DEVICE_RAM */ +#endif /* CONFIG_PROC_VMCORE */ + +static int virtio_mem_init_kdump(struct virtio_mem *vm) +{ + /* We must be prepared to receive a callback immediately. */ + virtio_device_ready(vm->vdev); +#ifdef CONFIG_PROC_VMCORE + dev_info(&vm->vdev->dev, "memory hot(un)plug disabled in kdump kernel\n"); + vm->vmcore_cb.pfn_is_ram = virtio_mem_vmcore_pfn_is_ram; +#ifdef CONFIG_PROC_VMCORE_DEVICE_RAM + vm->vmcore_cb.get_device_ram = virtio_mem_vmcore_get_device_ram; +#endif /* CONFIG_PROC_VMCORE_DEVICE_RAM */ + register_vmcore_cb(&vm->vmcore_cb); + return 0; +#else /* CONFIG_PROC_VMCORE */ + dev_warn(&vm->vdev->dev, "disabled in kdump kernel without vmcore\n"); + return -EBUSY; +#endif /* CONFIG_PROC_VMCORE */ +} + +static int virtio_mem_init(struct virtio_mem *vm) +{ + uint16_t node_id; + + if (!vm->vdev->config->get) { + dev_err(&vm->vdev->dev, "config access disabled\n"); + return -EINVAL; + } + + /* Fetch all properties that can't change. */ + virtio_cread_le(vm->vdev, struct virtio_mem_config, plugged_size, + &vm->plugged_size); + virtio_cread_le(vm->vdev, struct virtio_mem_config, block_size, + &vm->device_block_size); + virtio_cread_le(vm->vdev, struct virtio_mem_config, node_id, + &node_id); + vm->nid = virtio_mem_translate_node_id(vm, node_id); + virtio_cread_le(vm->vdev, struct virtio_mem_config, addr, &vm->addr); + virtio_cread_le(vm->vdev, struct virtio_mem_config, region_size, + &vm->region_size); + virtio_cread_le(vm->vdev, struct virtio_mem_config, usable_region_size, + &vm->usable_region_size); + + /* Determine the nid for the device based on the lowest address. */ + if (vm->nid == NUMA_NO_NODE) + vm->nid = memory_add_physaddr_to_nid(vm->addr); + + dev_info(&vm->vdev->dev, "start address: 0x%llx", vm->addr); + dev_info(&vm->vdev->dev, "region size: 0x%llx", vm->region_size); + dev_info(&vm->vdev->dev, "device block size: 0x%llx", + (unsigned long long)vm->device_block_size); + if (vm->nid != NUMA_NO_NODE && IS_ENABLED(CONFIG_NUMA)) + dev_info(&vm->vdev->dev, "nid: %d", vm->nid); + + /* + * We don't want to (un)plug or reuse any memory when in kdump. The + * memory is still accessible (but not exposed to Linux). + */ + if (vm->in_kdump) + return virtio_mem_init_kdump(vm); + return virtio_mem_init_hotplug(vm); +} + +static int virtio_mem_create_resource(struct virtio_mem *vm) +{ + /* + * When force-unloading the driver and removing the device, we + * could have a garbage pointer. Duplicate the string. + */ + const char *name = kstrdup(dev_name(&vm->vdev->dev), GFP_KERNEL); + + if (!name) + return -ENOMEM; + + /* Disallow mapping device memory via /dev/mem completely. */ + vm->parent_resource = __request_mem_region(vm->addr, vm->region_size, + name, IORESOURCE_SYSTEM_RAM | + IORESOURCE_EXCLUSIVE); + if (!vm->parent_resource) { + kfree(name); + dev_warn(&vm->vdev->dev, "could not reserve device region\n"); + dev_info(&vm->vdev->dev, + "reloading the driver is not supported\n"); + return -EBUSY; + } + + /* The memory is not actually busy - make add_memory() work. */ + vm->parent_resource->flags &= ~IORESOURCE_BUSY; + return 0; +} + +static void virtio_mem_delete_resource(struct virtio_mem *vm) +{ + const char *name; + + if (!vm->parent_resource) + return; + + name = vm->parent_resource->name; + release_resource(vm->parent_resource); + kfree(vm->parent_resource); + kfree(name); + vm->parent_resource = NULL; +} + +static int virtio_mem_range_has_system_ram(struct resource *res, void *arg) +{ + return 1; +} + +static bool virtio_mem_has_memory_added(struct virtio_mem *vm) +{ + const unsigned long flags = IORESOURCE_SYSTEM_RAM | IORESOURCE_BUSY; + + return walk_iomem_res_desc(IORES_DESC_NONE, flags, vm->addr, + vm->addr + vm->region_size, NULL, + virtio_mem_range_has_system_ram) == 1; +} + +static int virtio_mem_probe(struct virtio_device *vdev) +{ + struct virtio_mem *vm; + int rc; + + BUILD_BUG_ON(sizeof(struct virtio_mem_req) != 24); + BUILD_BUG_ON(sizeof(struct virtio_mem_resp) != 10); + + vdev->priv = vm = kzalloc(sizeof(*vm), GFP_KERNEL); + if (!vm) + return -ENOMEM; + + init_waitqueue_head(&vm->host_resp); + vm->vdev = vdev; + INIT_WORK(&vm->wq, virtio_mem_run_wq); + mutex_init(&vm->hotplug_mutex); + INIT_LIST_HEAD(&vm->next); + spin_lock_init(&vm->removal_lock); + hrtimer_setup(&vm->retry_timer, virtio_mem_timer_expired, CLOCK_MONOTONIC, + HRTIMER_MODE_REL); + vm->retry_timer_ms = VIRTIO_MEM_RETRY_TIMER_MIN_MS; + vm->in_kdump = is_kdump_kernel(); + + /* register the virtqueue */ + rc = virtio_mem_init_vq(vm); + if (rc) + goto out_free_vm; + + /* initialize the device by querying the config */ + rc = virtio_mem_init(vm); + if (rc) + goto out_del_vq; + + /* trigger a config update to start processing the requested_size */ + if (!vm->in_kdump) { + atomic_set(&vm->config_changed, 1); + queue_work(system_freezable_wq, &vm->wq); + } + + return 0; +out_del_vq: + vdev->config->del_vqs(vdev); +out_free_vm: + kfree(vm); + vdev->priv = NULL; + + return rc; +} + +static void virtio_mem_deinit_hotplug(struct virtio_mem *vm) +{ + unsigned long mb_id; + int rc; + + /* + * Make sure the workqueue won't be triggered anymore and no memory + * blocks can be onlined/offlined until we're finished here. + */ + mutex_lock(&vm->hotplug_mutex); + spin_lock_irq(&vm->removal_lock); + vm->removing = true; + spin_unlock_irq(&vm->removal_lock); + mutex_unlock(&vm->hotplug_mutex); + + /* wait until the workqueue stopped */ + cancel_work_sync(&vm->wq); + hrtimer_cancel(&vm->retry_timer); + + if (vm->in_sbm) { + /* + * After we unregistered our callbacks, user space can online + * partially plugged offline blocks. Make sure to remove them. + */ + virtio_mem_sbm_for_each_mb(vm, mb_id, + VIRTIO_MEM_SBM_MB_OFFLINE_PARTIAL) { + rc = virtio_mem_sbm_remove_mb(vm, mb_id); + BUG_ON(rc); + virtio_mem_sbm_set_mb_state(vm, mb_id, + VIRTIO_MEM_SBM_MB_UNUSED); + } + /* + * After we unregistered our callbacks, user space can no longer + * offline partially plugged online memory blocks. No need to + * worry about them. + */ + } + + /* unregister callbacks */ + unregister_virtio_mem_device(vm); + unregister_pm_notifier(&vm->pm_notifier); + unregister_memory_notifier(&vm->memory_notifier); + + /* + * There is no way we could reliably remove all memory we have added to + * the system. And there is no way to stop the driver/device from going + * away. Warn at least. + */ + if (virtio_mem_has_memory_added(vm)) { + dev_warn(&vm->vdev->dev, + "device still has system memory added\n"); + } else { + virtio_mem_delete_resource(vm); + kfree_const(vm->resource_name); + memory_group_unregister(vm->mgid); + } + + /* remove all tracking data - no locking needed */ + if (vm->in_sbm) { + vfree(vm->sbm.mb_states); + vfree(vm->sbm.sb_states); + } else { + vfree(vm->bbm.bb_states); + } +} + +static void virtio_mem_deinit_kdump(struct virtio_mem *vm) +{ +#ifdef CONFIG_PROC_VMCORE + unregister_vmcore_cb(&vm->vmcore_cb); +#endif /* CONFIG_PROC_VMCORE */ +} + +static void virtio_mem_remove(struct virtio_device *vdev) +{ + struct virtio_mem *vm = vdev->priv; + + if (vm->in_kdump) + virtio_mem_deinit_kdump(vm); + else + virtio_mem_deinit_hotplug(vm); + + /* reset the device and cleanup the queues */ + virtio_reset_device(vdev); + vdev->config->del_vqs(vdev); + + kfree(vm); + vdev->priv = NULL; +} + +static void virtio_mem_config_changed(struct virtio_device *vdev) +{ + struct virtio_mem *vm = vdev->priv; + + if (unlikely(vm->in_kdump)) + return; + + atomic_set(&vm->config_changed, 1); + virtio_mem_retry(vm); +} + +#ifdef CONFIG_PM_SLEEP +static int virtio_mem_freeze(struct virtio_device *vdev) +{ + struct virtio_mem *vm = vdev->priv; + + /* + * We block hibernation using the PM notifier completely. The workqueue + * is already frozen by the PM core at this point, so we simply + * reset the device and cleanup the queues. + */ + if (pm_suspend_target_state != PM_SUSPEND_TO_IDLE && + vm->plugged_size && + !virtio_has_feature(vm->vdev, VIRTIO_MEM_F_PERSISTENT_SUSPEND)) { + dev_err(&vm->vdev->dev, + "suspending with plugged memory is not supported\n"); + return -EPERM; + } + + virtio_reset_device(vdev); + vdev->config->del_vqs(vdev); + vm->vq = NULL; + return 0; +} + +static int virtio_mem_restore(struct virtio_device *vdev) +{ + struct virtio_mem *vm = vdev->priv; + int ret; + + ret = virtio_mem_init_vq(vm); + if (ret) + return ret; + virtio_device_ready(vdev); + + /* Let's check if anything changed. */ + virtio_mem_config_changed(vdev); + return 0; +} +#endif + +static unsigned int virtio_mem_features[] = { +#if defined(CONFIG_NUMA) && defined(CONFIG_ACPI_NUMA) + VIRTIO_MEM_F_ACPI_PXM, +#endif + VIRTIO_MEM_F_UNPLUGGED_INACCESSIBLE, + VIRTIO_MEM_F_PERSISTENT_SUSPEND, +}; + +static const struct virtio_device_id virtio_mem_id_table[] = { + { VIRTIO_ID_MEM, VIRTIO_DEV_ANY_ID }, + { 0 }, +}; + +static struct virtio_driver virtio_mem_driver = { + .feature_table = virtio_mem_features, + .feature_table_size = ARRAY_SIZE(virtio_mem_features), + .driver.name = KBUILD_MODNAME, + .id_table = virtio_mem_id_table, + .probe = virtio_mem_probe, + .remove = virtio_mem_remove, + .config_changed = virtio_mem_config_changed, +#ifdef CONFIG_PM_SLEEP + .freeze = virtio_mem_freeze, + .restore = virtio_mem_restore, +#endif +}; + +module_virtio_driver(virtio_mem_driver); +MODULE_DEVICE_TABLE(virtio, virtio_mem_id_table); +MODULE_AUTHOR("David Hildenbrand <david@redhat.com>"); +MODULE_DESCRIPTION("Virtio-mem driver"); +MODULE_LICENSE("GPL"); diff --git a/drivers/virtio/virtio_mmio.c b/drivers/virtio/virtio_mmio.c index 1ba0d6831015..b152a1eca05a 100644 --- a/drivers/virtio/virtio_mmio.c +++ b/drivers/virtio/virtio_mmio.c @@ -1,7 +1,8 @@ +// SPDX-License-Identifier: GPL-2.0-or-later /* * Virtio memory mapped device driver * - * Copyright 2011, ARM Ltd. + * Copyright 2011-2014, ARM Ltd. * * This module allows virtio devices to be used over a virtual, memory mapped * platform device. @@ -48,57 +49,25 @@ * virtio_mmio.device=0x100@0x100b0000:48 \ * virtio_mmio.device=1K@0x1001e000:74 * - * - * - * Registers layout (all 32-bit wide): - * - * offset d. name description - * ------ -- ---------------- ----------------- - * - * 0x000 R MagicValue Magic value "virt" - * 0x004 R Version Device version (current max. 1) - * 0x008 R DeviceID Virtio device ID - * 0x00c R VendorID Virtio vendor ID - * - * 0x010 R HostFeatures Features supported by the host - * 0x014 W HostFeaturesSel Set of host features to access via HostFeatures - * - * 0x020 W GuestFeatures Features activated by the guest - * 0x024 W GuestFeaturesSel Set of activated features to set via GuestFeatures - * 0x028 W GuestPageSize Size of guest's memory page in bytes - * - * 0x030 W QueueSel Queue selector - * 0x034 R QueueNumMax Maximum size of the currently selected queue - * 0x038 W QueueNum Queue size for the currently selected queue - * 0x03c W QueueAlign Used Ring alignment for the current queue - * 0x040 RW QueuePFN PFN for the currently selected queue - * - * 0x050 W QueueNotify Queue notifier - * 0x060 R InterruptStatus Interrupt status register - * 0x064 W InterruptACK Interrupt acknowledge register - * 0x070 RW Status Device status register - * - * 0x100+ RW Device-specific configuration space - * * Based on Virtio PCI driver by Anthony Liguori, copyright IBM Corp. 2007 - * - * This work is licensed under the terms of the GNU GPL, version 2 or later. - * See the COPYING file in the top-level directory. */ #define pr_fmt(fmt) "virtio-mmio: " fmt +#include <linux/acpi.h> +#include <linux/dma-mapping.h> #include <linux/highmem.h> #include <linux/interrupt.h> #include <linux/io.h> #include <linux/list.h> #include <linux/module.h> +#include <linux/of.h> #include <linux/platform_device.h> +#include <linux/pm.h> #include <linux/slab.h> -#include <linux/spinlock.h> #include <linux/virtio.h> #include <linux/virtio_config.h> -#include <linux/virtio_mmio.h> +#include <uapi/linux/virtio_mmio.h> #include <linux/virtio_ring.h> @@ -118,75 +87,143 @@ struct virtio_mmio_device { void __iomem *base; unsigned long version; - - /* a list of queues so we can dispatch IRQs */ - spinlock_t lock; - struct list_head virtqueues; }; -struct virtio_mmio_vq_info { - /* the actual virtqueue */ - struct virtqueue *vq; - - /* the number of entries in the queue */ - unsigned int num; - - /* the virtual address of the ring queue */ - void *queue; - - /* the list node for the virtqueues list */ - struct list_head node; -}; - - - /* Configuration interface */ -static u32 vm_get_features(struct virtio_device *vdev) +static u64 vm_get_features(struct virtio_device *vdev) { struct virtio_mmio_device *vm_dev = to_virtio_mmio_device(vdev); + u64 features; - /* TODO: Features > 32 bits */ - writel(0, vm_dev->base + VIRTIO_MMIO_HOST_FEATURES_SEL); + writel(1, vm_dev->base + VIRTIO_MMIO_DEVICE_FEATURES_SEL); + features = readl(vm_dev->base + VIRTIO_MMIO_DEVICE_FEATURES); + features <<= 32; - return readl(vm_dev->base + VIRTIO_MMIO_HOST_FEATURES); + writel(0, vm_dev->base + VIRTIO_MMIO_DEVICE_FEATURES_SEL); + features |= readl(vm_dev->base + VIRTIO_MMIO_DEVICE_FEATURES); + + return features; } -static void vm_finalize_features(struct virtio_device *vdev) +static int vm_finalize_features(struct virtio_device *vdev) { struct virtio_mmio_device *vm_dev = to_virtio_mmio_device(vdev); - int i; /* Give virtio_ring a chance to accept features. */ vring_transport_features(vdev); - for (i = 0; i < ARRAY_SIZE(vdev->features); i++) { - writel(i, vm_dev->base + VIRTIO_MMIO_GUEST_FEATURES_SEL); - writel(vdev->features[i], - vm_dev->base + VIRTIO_MMIO_GUEST_FEATURES); + /* Make sure there are no mixed devices */ + if (vm_dev->version == 2 && + !__virtio_test_bit(vdev, VIRTIO_F_VERSION_1)) { + dev_err(&vdev->dev, "New virtio-mmio devices (version 2) must provide VIRTIO_F_VERSION_1 feature!\n"); + return -EINVAL; } + + writel(1, vm_dev->base + VIRTIO_MMIO_DRIVER_FEATURES_SEL); + writel((u32)(vdev->features >> 32), + vm_dev->base + VIRTIO_MMIO_DRIVER_FEATURES); + + writel(0, vm_dev->base + VIRTIO_MMIO_DRIVER_FEATURES_SEL); + writel((u32)vdev->features, + vm_dev->base + VIRTIO_MMIO_DRIVER_FEATURES); + + return 0; } -static void vm_get(struct virtio_device *vdev, unsigned offset, - void *buf, unsigned len) +static void vm_get(struct virtio_device *vdev, unsigned int offset, + void *buf, unsigned int len) { struct virtio_mmio_device *vm_dev = to_virtio_mmio_device(vdev); - u8 *ptr = buf; - int i; + void __iomem *base = vm_dev->base + VIRTIO_MMIO_CONFIG; + u8 b; + __le16 w; + __le32 l; + + if (vm_dev->version == 1) { + u8 *ptr = buf; + int i; + + for (i = 0; i < len; i++) + ptr[i] = readb(base + offset + i); + return; + } - for (i = 0; i < len; i++) - ptr[i] = readb(vm_dev->base + VIRTIO_MMIO_CONFIG + offset + i); + switch (len) { + case 1: + b = readb(base + offset); + memcpy(buf, &b, sizeof b); + break; + case 2: + w = cpu_to_le16(readw(base + offset)); + memcpy(buf, &w, sizeof w); + break; + case 4: + l = cpu_to_le32(readl(base + offset)); + memcpy(buf, &l, sizeof l); + break; + case 8: + l = cpu_to_le32(readl(base + offset)); + memcpy(buf, &l, sizeof l); + l = cpu_to_le32(ioread32(base + offset + sizeof l)); + memcpy(buf + sizeof l, &l, sizeof l); + break; + default: + BUG(); + } } -static void vm_set(struct virtio_device *vdev, unsigned offset, - const void *buf, unsigned len) +static void vm_set(struct virtio_device *vdev, unsigned int offset, + const void *buf, unsigned int len) { struct virtio_mmio_device *vm_dev = to_virtio_mmio_device(vdev); - const u8 *ptr = buf; - int i; + void __iomem *base = vm_dev->base + VIRTIO_MMIO_CONFIG; + u8 b; + __le16 w; + __le32 l; + + if (vm_dev->version == 1) { + const u8 *ptr = buf; + int i; + + for (i = 0; i < len; i++) + writeb(ptr[i], base + offset + i); + + return; + } - for (i = 0; i < len; i++) - writeb(ptr[i], vm_dev->base + VIRTIO_MMIO_CONFIG + offset + i); + switch (len) { + case 1: + memcpy(&b, buf, sizeof b); + writeb(b, base + offset); + break; + case 2: + memcpy(&w, buf, sizeof w); + writew(le16_to_cpu(w), base + offset); + break; + case 4: + memcpy(&l, buf, sizeof l); + writel(le32_to_cpu(l), base + offset); + break; + case 8: + memcpy(&l, buf, sizeof l); + writel(le32_to_cpu(l), base + offset); + memcpy(&l, buf + sizeof l, sizeof l); + writel(le32_to_cpu(l), base + offset + sizeof l); + break; + default: + BUG(); + } +} + +static u32 vm_generation(struct virtio_device *vdev) +{ + struct virtio_mmio_device *vm_dev = to_virtio_mmio_device(vdev); + + if (vm_dev->version == 1) + return 0; + else + return readl(vm_dev->base + VIRTIO_MMIO_CONFIG_GENERATION); } static u8 vm_get_status(struct virtio_device *vdev) @@ -203,6 +240,11 @@ static void vm_set_status(struct virtio_device *vdev, u8 status) /* We should never be setting status to 0. */ BUG_ON(status == 0); + /* + * Per memory-barriers.txt, wmb() is not needed to guarantee + * that the cache coherent memory writes have completed + * before writing to the MMIO region. + */ writel(status, vm_dev->base + VIRTIO_MMIO_STATUS); } @@ -219,41 +261,46 @@ static void vm_reset(struct virtio_device *vdev) /* Transport interface */ /* the notify function used when creating a virt queue */ -static void vm_notify(struct virtqueue *vq) +static bool vm_notify(struct virtqueue *vq) { struct virtio_mmio_device *vm_dev = to_virtio_mmio_device(vq->vdev); /* We write the queue's selector into the notification register to * signal the other end */ writel(vq->index, vm_dev->base + VIRTIO_MMIO_QUEUE_NOTIFY); + return true; +} + +static bool vm_notify_with_data(struct virtqueue *vq) +{ + struct virtio_mmio_device *vm_dev = to_virtio_mmio_device(vq->vdev); + u32 data = vring_notification_data(vq); + + writel(data, vm_dev->base + VIRTIO_MMIO_QUEUE_NOTIFY); + + return true; } /* Notify all virtqueues on an interrupt. */ static irqreturn_t vm_interrupt(int irq, void *opaque) { struct virtio_mmio_device *vm_dev = opaque; - struct virtio_mmio_vq_info *info; - struct virtio_driver *vdrv = container_of(vm_dev->vdev.dev.driver, - struct virtio_driver, driver); + struct virtqueue *vq; unsigned long status; - unsigned long flags; irqreturn_t ret = IRQ_NONE; /* Read and acknowledge interrupts */ status = readl(vm_dev->base + VIRTIO_MMIO_INTERRUPT_STATUS); writel(status, vm_dev->base + VIRTIO_MMIO_INTERRUPT_ACK); - if (unlikely(status & VIRTIO_MMIO_INT_CONFIG) - && vdrv && vdrv->config_changed) { - vdrv->config_changed(&vm_dev->vdev); + if (unlikely(status & VIRTIO_MMIO_INT_CONFIG)) { + virtio_config_changed(&vm_dev->vdev); ret = IRQ_HANDLED; } if (likely(status & VIRTIO_MMIO_INT_VRING)) { - spin_lock_irqsave(&vm_dev->lock, flags); - list_for_each_entry(info, &vm_dev->virtqueues, node) - ret |= vring_interrupt(irq, info->vq); - spin_unlock_irqrestore(&vm_dev->lock, flags); + virtio_device_for_each_vq(&vm_dev->vdev, vq) + ret |= vring_interrupt(irq, vq); } return ret; @@ -264,23 +311,18 @@ static irqreturn_t vm_interrupt(int irq, void *opaque) static void vm_del_vq(struct virtqueue *vq) { struct virtio_mmio_device *vm_dev = to_virtio_mmio_device(vq->vdev); - struct virtio_mmio_vq_info *info = vq->priv; - unsigned long flags, size; unsigned int index = vq->index; - spin_lock_irqsave(&vm_dev->lock, flags); - list_del(&info->node); - spin_unlock_irqrestore(&vm_dev->lock, flags); - - vring_del_virtqueue(vq); - /* Select and deactivate the queue */ writel(index, vm_dev->base + VIRTIO_MMIO_QUEUE_SEL); - writel(0, vm_dev->base + VIRTIO_MMIO_QUEUE_PFN); + if (vm_dev->version == 1) { + writel(0, vm_dev->base + VIRTIO_MMIO_QUEUE_PFN); + } else { + writel(0, vm_dev->base + VIRTIO_MMIO_QUEUE_READY); + WARN_ON(readl(vm_dev->base + VIRTIO_MMIO_QUEUE_READY)); + } - size = PAGE_ALIGN(vring_size(info->num, VIRTIO_MMIO_VRING_ALIGN)); - free_pages_exact(info->queue, size); - kfree(info); + vring_del_virtqueue(vq); } static void vm_del_vqs(struct virtio_device *vdev) @@ -294,18 +336,28 @@ static void vm_del_vqs(struct virtio_device *vdev) free_irq(platform_get_irq(vm_dev->pdev, 0), vm_dev); } +static void vm_synchronize_cbs(struct virtio_device *vdev) +{ + struct virtio_mmio_device *vm_dev = to_virtio_mmio_device(vdev); + synchronize_irq(platform_get_irq(vm_dev->pdev, 0)); +} -static struct virtqueue *vm_setup_vq(struct virtio_device *vdev, unsigned index, +static struct virtqueue *vm_setup_vq(struct virtio_device *vdev, unsigned int index, void (*callback)(struct virtqueue *vq), - const char *name) + const char *name, bool ctx) { struct virtio_mmio_device *vm_dev = to_virtio_mmio_device(vdev); - struct virtio_mmio_vq_info *info; + bool (*notify)(struct virtqueue *vq); struct virtqueue *vq; - unsigned long flags, size; + unsigned int num; int err; + if (__virtio_test_bit(vdev, VIRTIO_F_NOTIFICATION_DATA)) + notify = vm_notify_with_data; + else + notify = vm_notify; + if (!name) return NULL; @@ -313,100 +365,114 @@ static struct virtqueue *vm_setup_vq(struct virtio_device *vdev, unsigned index, writel(index, vm_dev->base + VIRTIO_MMIO_QUEUE_SEL); /* Queue shouldn't already be set up. */ - if (readl(vm_dev->base + VIRTIO_MMIO_QUEUE_PFN)) { + if (readl(vm_dev->base + (vm_dev->version == 1 ? + VIRTIO_MMIO_QUEUE_PFN : VIRTIO_MMIO_QUEUE_READY))) { err = -ENOENT; goto error_available; } - /* Allocate and fill out our active queue description */ - info = kmalloc(sizeof(*info), GFP_KERNEL); - if (!info) { - err = -ENOMEM; - goto error_kmalloc; - } - - /* Allocate pages for the queue - start with a queue as big as - * possible (limited by maximum size allowed by device), drop down - * to a minimal size, just big enough to fit descriptor table - * and two rings (which makes it "alignment_size * 2") - */ - info->num = readl(vm_dev->base + VIRTIO_MMIO_QUEUE_NUM_MAX); - - /* If the device reports a 0 entry queue, we won't be able to - * use it to perform I/O, and vring_new_virtqueue() can't create - * empty queues anyway, so don't bother to set up the device. - */ - if (info->num == 0) { + num = readl(vm_dev->base + VIRTIO_MMIO_QUEUE_NUM_MAX); + if (num == 0) { err = -ENOENT; - goto error_alloc_pages; - } - - while (1) { - size = PAGE_ALIGN(vring_size(info->num, - VIRTIO_MMIO_VRING_ALIGN)); - /* Did the last iter shrink the queue below minimum size? */ - if (size < VIRTIO_MMIO_VRING_ALIGN * 2) { - err = -ENOMEM; - goto error_alloc_pages; - } - - info->queue = alloc_pages_exact(size, GFP_KERNEL | __GFP_ZERO); - if (info->queue) - break; - - info->num /= 2; + goto error_new_virtqueue; } - /* Activate the queue */ - writel(info->num, vm_dev->base + VIRTIO_MMIO_QUEUE_NUM); - writel(VIRTIO_MMIO_VRING_ALIGN, - vm_dev->base + VIRTIO_MMIO_QUEUE_ALIGN); - writel(virt_to_phys(info->queue) >> PAGE_SHIFT, - vm_dev->base + VIRTIO_MMIO_QUEUE_PFN); - /* Create the vring */ - vq = vring_new_virtqueue(index, info->num, VIRTIO_MMIO_VRING_ALIGN, vdev, - true, info->queue, vm_notify, callback, name); + vq = vring_create_virtqueue(index, num, VIRTIO_MMIO_VRING_ALIGN, vdev, + true, true, ctx, notify, callback, name); if (!vq) { err = -ENOMEM; goto error_new_virtqueue; } - vq->priv = info; - info->vq = vq; + vq->num_max = num; - spin_lock_irqsave(&vm_dev->lock, flags); - list_add(&info->node, &vm_dev->virtqueues); - spin_unlock_irqrestore(&vm_dev->lock, flags); + /* Activate the queue */ + writel(virtqueue_get_vring_size(vq), vm_dev->base + VIRTIO_MMIO_QUEUE_NUM); + if (vm_dev->version == 1) { + u64 q_pfn = virtqueue_get_desc_addr(vq) >> PAGE_SHIFT; + + /* + * virtio-mmio v1 uses a 32bit QUEUE PFN. If we have something + * that doesn't fit in 32bit, fail the setup rather than + * pretending to be successful. + */ + if (q_pfn >> 32) { + dev_err(&vdev->dev, + "platform bug: legacy virtio-mmio must not be used with RAM above 0x%llxGB\n", + 0x1ULL << (32 + PAGE_SHIFT - 30)); + err = -E2BIG; + goto error_bad_pfn; + } + + writel(PAGE_SIZE, vm_dev->base + VIRTIO_MMIO_QUEUE_ALIGN); + writel(q_pfn, vm_dev->base + VIRTIO_MMIO_QUEUE_PFN); + } else { + u64 addr; + + addr = virtqueue_get_desc_addr(vq); + writel((u32)addr, vm_dev->base + VIRTIO_MMIO_QUEUE_DESC_LOW); + writel((u32)(addr >> 32), + vm_dev->base + VIRTIO_MMIO_QUEUE_DESC_HIGH); + + addr = virtqueue_get_avail_addr(vq); + writel((u32)addr, vm_dev->base + VIRTIO_MMIO_QUEUE_AVAIL_LOW); + writel((u32)(addr >> 32), + vm_dev->base + VIRTIO_MMIO_QUEUE_AVAIL_HIGH); + + addr = virtqueue_get_used_addr(vq); + writel((u32)addr, vm_dev->base + VIRTIO_MMIO_QUEUE_USED_LOW); + writel((u32)(addr >> 32), + vm_dev->base + VIRTIO_MMIO_QUEUE_USED_HIGH); + + writel(1, vm_dev->base + VIRTIO_MMIO_QUEUE_READY); + } return vq; +error_bad_pfn: + vring_del_virtqueue(vq); error_new_virtqueue: - writel(0, vm_dev->base + VIRTIO_MMIO_QUEUE_PFN); - free_pages_exact(info->queue, size); -error_alloc_pages: - kfree(info); -error_kmalloc: + if (vm_dev->version == 1) { + writel(0, vm_dev->base + VIRTIO_MMIO_QUEUE_PFN); + } else { + writel(0, vm_dev->base + VIRTIO_MMIO_QUEUE_READY); + WARN_ON(readl(vm_dev->base + VIRTIO_MMIO_QUEUE_READY)); + } error_available: return ERR_PTR(err); } -static int vm_find_vqs(struct virtio_device *vdev, unsigned nvqs, +static int vm_find_vqs(struct virtio_device *vdev, unsigned int nvqs, struct virtqueue *vqs[], - vq_callback_t *callbacks[], - const char *names[]) + struct virtqueue_info vqs_info[], + struct irq_affinity *desc) { struct virtio_mmio_device *vm_dev = to_virtio_mmio_device(vdev); - unsigned int irq = platform_get_irq(vm_dev->pdev, 0); - int i, err; + int irq = platform_get_irq(vm_dev->pdev, 0); + int i, err, queue_idx = 0; + + if (irq < 0) + return irq; err = request_irq(irq, vm_interrupt, IRQF_SHARED, dev_name(&vdev->dev), vm_dev); if (err) return err; + if (of_property_read_bool(vm_dev->pdev->dev.of_node, "wakeup-source")) + enable_irq_wake(irq); + for (i = 0; i < nvqs; ++i) { - vqs[i] = vm_setup_vq(vdev, i, callbacks[i], names[i]); + struct virtqueue_info *vqi = &vqs_info[i]; + + if (!vqi->name) { + vqs[i] = NULL; + continue; + } + + vqs[i] = vm_setup_vq(vdev, queue_idx++, vqi->callback, + vqi->name, vqi->ctx); if (IS_ERR(vqs[i])) { vm_del_vqs(vdev); return PTR_ERR(vqs[i]); @@ -423,9 +489,40 @@ static const char *vm_bus_name(struct virtio_device *vdev) return vm_dev->pdev->name; } +static bool vm_get_shm_region(struct virtio_device *vdev, + struct virtio_shm_region *region, u8 id) +{ + struct virtio_mmio_device *vm_dev = to_virtio_mmio_device(vdev); + u64 len, addr; + + /* Select the region we're interested in */ + writel(id, vm_dev->base + VIRTIO_MMIO_SHM_SEL); + + /* Read the region size */ + len = (u64) readl(vm_dev->base + VIRTIO_MMIO_SHM_LEN_LOW); + len |= (u64) readl(vm_dev->base + VIRTIO_MMIO_SHM_LEN_HIGH) << 32; + + region->len = len; + + /* Check if region length is -1. If that's the case, the shared memory + * region does not exist and there is no need to proceed further. + */ + if (len == ~(u64)0) + return false; + + /* Read the region base address */ + addr = (u64) readl(vm_dev->base + VIRTIO_MMIO_SHM_BASE_LOW); + addr |= (u64) readl(vm_dev->base + VIRTIO_MMIO_SHM_BASE_HIGH) << 32; + + region->addr = addr; + + return true; +} + static const struct virtio_config_ops virtio_mmio_config_ops = { .get = vm_get, .set = vm_set, + .generation = vm_generation, .get_status = vm_get_status, .set_status = vm_set_status, .reset = vm_reset, @@ -434,72 +531,129 @@ static const struct virtio_config_ops virtio_mmio_config_ops = { .get_features = vm_get_features, .finalize_features = vm_finalize_features, .bus_name = vm_bus_name, + .get_shm_region = vm_get_shm_region, + .synchronize_cbs = vm_synchronize_cbs, +}; + +#ifdef CONFIG_PM_SLEEP +static int virtio_mmio_freeze(struct device *dev) +{ + struct virtio_mmio_device *vm_dev = dev_get_drvdata(dev); + + return virtio_device_freeze(&vm_dev->vdev); +} + +static int virtio_mmio_restore(struct device *dev) +{ + struct virtio_mmio_device *vm_dev = dev_get_drvdata(dev); + + if (vm_dev->version == 1) + writel(PAGE_SIZE, vm_dev->base + VIRTIO_MMIO_GUEST_PAGE_SIZE); + + return virtio_device_restore(&vm_dev->vdev); +} + +static const struct dev_pm_ops virtio_mmio_pm_ops = { + SET_SYSTEM_SLEEP_PM_OPS(virtio_mmio_freeze, virtio_mmio_restore) }; +#endif +static void virtio_mmio_release_dev(struct device *_d) +{ + struct virtio_device *vdev = + container_of(_d, struct virtio_device, dev); + struct virtio_mmio_device *vm_dev = to_virtio_mmio_device(vdev); + kfree(vm_dev); +} /* Platform device */ static int virtio_mmio_probe(struct platform_device *pdev) { struct virtio_mmio_device *vm_dev; - struct resource *mem; unsigned long magic; + int rc; - mem = platform_get_resource(pdev, IORESOURCE_MEM, 0); - if (!mem) - return -EINVAL; - - if (!devm_request_mem_region(&pdev->dev, mem->start, - resource_size(mem), pdev->name)) - return -EBUSY; - - vm_dev = devm_kzalloc(&pdev->dev, sizeof(*vm_dev), GFP_KERNEL); + vm_dev = kzalloc(sizeof(*vm_dev), GFP_KERNEL); if (!vm_dev) - return -ENOMEM; + return -ENOMEM; vm_dev->vdev.dev.parent = &pdev->dev; + vm_dev->vdev.dev.release = virtio_mmio_release_dev; vm_dev->vdev.config = &virtio_mmio_config_ops; vm_dev->pdev = pdev; - INIT_LIST_HEAD(&vm_dev->virtqueues); - spin_lock_init(&vm_dev->lock); - vm_dev->base = devm_ioremap(&pdev->dev, mem->start, resource_size(mem)); - if (vm_dev->base == NULL) - return -EFAULT; + vm_dev->base = devm_platform_ioremap_resource(pdev, 0); + if (IS_ERR(vm_dev->base)) { + rc = PTR_ERR(vm_dev->base); + goto free_vm_dev; + } /* Check magic value */ magic = readl(vm_dev->base + VIRTIO_MMIO_MAGIC_VALUE); - if (memcmp(&magic, "virt", 4) != 0) { + if (magic != ('v' | 'i' << 8 | 'r' << 16 | 't' << 24)) { dev_warn(&pdev->dev, "Wrong magic value 0x%08lx!\n", magic); - return -ENODEV; + rc = -ENODEV; + goto free_vm_dev; } /* Check device version */ vm_dev->version = readl(vm_dev->base + VIRTIO_MMIO_VERSION); - if (vm_dev->version != 1) { + if (vm_dev->version < 1 || vm_dev->version > 2) { dev_err(&pdev->dev, "Version %ld not supported!\n", vm_dev->version); - return -ENXIO; + rc = -ENXIO; + goto free_vm_dev; } vm_dev->vdev.id.device = readl(vm_dev->base + VIRTIO_MMIO_DEVICE_ID); + if (vm_dev->vdev.id.device == 0) { + /* + * virtio-mmio device with an ID 0 is a (dummy) placeholder + * with no function. End probing now with no error reported. + */ + rc = -ENODEV; + goto free_vm_dev; + } vm_dev->vdev.id.vendor = readl(vm_dev->base + VIRTIO_MMIO_VENDOR_ID); - writel(PAGE_SIZE, vm_dev->base + VIRTIO_MMIO_GUEST_PAGE_SIZE); + if (vm_dev->version == 1) { + writel(PAGE_SIZE, vm_dev->base + VIRTIO_MMIO_GUEST_PAGE_SIZE); + + rc = dma_set_mask(&pdev->dev, DMA_BIT_MASK(64)); + /* + * In the legacy case, ensure our coherently-allocated virtio + * ring will be at an address expressable as a 32-bit PFN. + */ + if (!rc) + dma_set_coherent_mask(&pdev->dev, + DMA_BIT_MASK(32 + PAGE_SHIFT)); + } else { + rc = dma_set_mask_and_coherent(&pdev->dev, DMA_BIT_MASK(64)); + } + if (rc) + rc = dma_set_mask_and_coherent(&pdev->dev, DMA_BIT_MASK(32)); + if (rc) + dev_warn(&pdev->dev, "Failed to enable 64-bit or 32-bit DMA. Trying to continue, but this might not work.\n"); platform_set_drvdata(pdev, vm_dev); - return register_virtio_device(&vm_dev->vdev); + rc = register_virtio_device(&vm_dev->vdev); + if (rc) + put_device(&vm_dev->vdev.dev); + + return rc; + +free_vm_dev: + kfree(vm_dev); + return rc; } -static int virtio_mmio_remove(struct platform_device *pdev) +static void virtio_mmio_remove(struct platform_device *pdev) { struct virtio_mmio_device *vm_dev = platform_get_drvdata(pdev); - unregister_virtio_device(&vm_dev->vdev); - - return 0; } @@ -521,7 +675,7 @@ static int vm_cmdline_set(const char *device, int err; struct resource resources[2] = {}; char *str; - long long int base, size; + long long base, size; unsigned int irq; int processed, consumed = 0; struct platform_device *pdev; @@ -535,11 +689,11 @@ static int vm_cmdline_set(const char *device, &vm_cmdline_id, &consumed); /* - * sscanf() must processes at least 2 chunks; also there + * sscanf() must process at least 2 chunks; also there * must be no extra characters after the last chunk, so * str[consumed] must be '\0' */ - if (processed < 2 || str[consumed]) + if (processed < 2 || str[consumed] || irq == 0) return -EINVAL; resources[0].flags = IORESOURCE_MEM; @@ -552,6 +706,7 @@ static int vm_cmdline_set(const char *device, if (!vm_cmdline_parent_registered) { err = device_register(&vm_cmdline_parent); if (err) { + put_device(&vm_cmdline_parent); pr_err("Failed to register parent device!\n"); return err; } @@ -567,10 +722,8 @@ static int vm_cmdline_set(const char *device, pdev = platform_device_register_resndata(&vm_cmdline_parent, "virtio-mmio", vm_cmdline_id++, resources, ARRAY_SIZE(resources), NULL, 0); - if (IS_ERR(pdev)) - return PTR_ERR(pdev); - return 0; + return PTR_ERR_OR_ZERO(pdev); } static int vm_cmdline_get_device(struct device *dev, void *data) @@ -595,7 +748,7 @@ static int vm_cmdline_get(char *buffer, const struct kernel_param *kp) return strlen(buffer) + 1; } -static struct kernel_param_ops vm_cmdline_param_ops = { +static const struct kernel_param_ops vm_cmdline_param_ops = { .set = vm_cmdline_set, .get = vm_cmdline_get, }; @@ -630,19 +783,30 @@ static void vm_unregister_cmdline_devices(void) /* Platform driver */ -static struct of_device_id virtio_mmio_match[] = { +static const struct of_device_id virtio_mmio_match[] = { { .compatible = "virtio,mmio", }, {}, }; MODULE_DEVICE_TABLE(of, virtio_mmio_match); +#ifdef CONFIG_ACPI +static const struct acpi_device_id virtio_mmio_acpi_match[] = { + { "LNRO0005", }, + { } +}; +MODULE_DEVICE_TABLE(acpi, virtio_mmio_acpi_match); +#endif + static struct platform_driver virtio_mmio_driver = { .probe = virtio_mmio_probe, .remove = virtio_mmio_remove, .driver = { .name = "virtio-mmio", - .owner = THIS_MODULE, .of_match_table = virtio_mmio_match, + .acpi_match_table = ACPI_PTR(virtio_mmio_acpi_match), +#ifdef CONFIG_PM_SLEEP + .pm = &virtio_mmio_pm_ops, +#endif }, }; diff --git a/drivers/virtio/virtio_pci.c b/drivers/virtio/virtio_pci.c deleted file mode 100644 index 1aba255b5879..000000000000 --- a/drivers/virtio/virtio_pci.c +++ /dev/null @@ -1,832 +0,0 @@ -/* - * Virtio PCI driver - * - * This module allows virtio devices to be used over a virtual PCI device. - * This can be used with QEMU based VMMs like KVM or Xen. - * - * Copyright IBM Corp. 2007 - * - * Authors: - * Anthony Liguori <aliguori@us.ibm.com> - * - * This work is licensed under the terms of the GNU GPL, version 2 or later. - * See the COPYING file in the top-level directory. - * - */ - -#include <linux/module.h> -#include <linux/list.h> -#include <linux/pci.h> -#include <linux/slab.h> -#include <linux/interrupt.h> -#include <linux/virtio.h> -#include <linux/virtio_config.h> -#include <linux/virtio_ring.h> -#include <linux/virtio_pci.h> -#include <linux/highmem.h> -#include <linux/spinlock.h> - -MODULE_AUTHOR("Anthony Liguori <aliguori@us.ibm.com>"); -MODULE_DESCRIPTION("virtio-pci"); -MODULE_LICENSE("GPL"); -MODULE_VERSION("1"); - -/* Our device structure */ -struct virtio_pci_device -{ - struct virtio_device vdev; - struct pci_dev *pci_dev; - - /* the IO mapping for the PCI config space */ - void __iomem *ioaddr; - - /* a list of queues so we can dispatch IRQs */ - spinlock_t lock; - struct list_head virtqueues; - - /* MSI-X support */ - int msix_enabled; - int intx_enabled; - struct msix_entry *msix_entries; - cpumask_var_t *msix_affinity_masks; - /* Name strings for interrupts. This size should be enough, - * and I'm too lazy to allocate each name separately. */ - char (*msix_names)[256]; - /* Number of available vectors */ - unsigned msix_vectors; - /* Vectors allocated, excluding per-vq vectors if any */ - unsigned msix_used_vectors; - - /* Status saved during hibernate/restore */ - u8 saved_status; - - /* Whether we have vector per vq */ - bool per_vq_vectors; -}; - -/* Constants for MSI-X */ -/* Use first vector for configuration changes, second and the rest for - * virtqueues Thus, we need at least 2 vectors for MSI. */ -enum { - VP_MSIX_CONFIG_VECTOR = 0, - VP_MSIX_VQ_VECTOR = 1, -}; - -struct virtio_pci_vq_info -{ - /* the actual virtqueue */ - struct virtqueue *vq; - - /* the number of entries in the queue */ - int num; - - /* the virtual address of the ring queue */ - void *queue; - - /* the list node for the virtqueues list */ - struct list_head node; - - /* MSI-X vector (or none) */ - unsigned msix_vector; -}; - -/* Qumranet donated their vendor ID for devices 0x1000 thru 0x10FF. */ -static DEFINE_PCI_DEVICE_TABLE(virtio_pci_id_table) = { - { PCI_DEVICE(0x1af4, PCI_ANY_ID) }, - { 0 } -}; - -MODULE_DEVICE_TABLE(pci, virtio_pci_id_table); - -/* Convert a generic virtio device to our structure */ -static struct virtio_pci_device *to_vp_device(struct virtio_device *vdev) -{ - return container_of(vdev, struct virtio_pci_device, vdev); -} - -/* virtio config->get_features() implementation */ -static u32 vp_get_features(struct virtio_device *vdev) -{ - struct virtio_pci_device *vp_dev = to_vp_device(vdev); - - /* When someone needs more than 32 feature bits, we'll need to - * steal a bit to indicate that the rest are somewhere else. */ - return ioread32(vp_dev->ioaddr + VIRTIO_PCI_HOST_FEATURES); -} - -/* virtio config->finalize_features() implementation */ -static void vp_finalize_features(struct virtio_device *vdev) -{ - struct virtio_pci_device *vp_dev = to_vp_device(vdev); - - /* Give virtio_ring a chance to accept features. */ - vring_transport_features(vdev); - - /* We only support 32 feature bits. */ - BUILD_BUG_ON(ARRAY_SIZE(vdev->features) != 1); - iowrite32(vdev->features[0], vp_dev->ioaddr+VIRTIO_PCI_GUEST_FEATURES); -} - -/* virtio config->get() implementation */ -static void vp_get(struct virtio_device *vdev, unsigned offset, - void *buf, unsigned len) -{ - struct virtio_pci_device *vp_dev = to_vp_device(vdev); - void __iomem *ioaddr = vp_dev->ioaddr + - VIRTIO_PCI_CONFIG(vp_dev) + offset; - u8 *ptr = buf; - int i; - - for (i = 0; i < len; i++) - ptr[i] = ioread8(ioaddr + i); -} - -/* the config->set() implementation. it's symmetric to the config->get() - * implementation */ -static void vp_set(struct virtio_device *vdev, unsigned offset, - const void *buf, unsigned len) -{ - struct virtio_pci_device *vp_dev = to_vp_device(vdev); - void __iomem *ioaddr = vp_dev->ioaddr + - VIRTIO_PCI_CONFIG(vp_dev) + offset; - const u8 *ptr = buf; - int i; - - for (i = 0; i < len; i++) - iowrite8(ptr[i], ioaddr + i); -} - -/* config->{get,set}_status() implementations */ -static u8 vp_get_status(struct virtio_device *vdev) -{ - struct virtio_pci_device *vp_dev = to_vp_device(vdev); - return ioread8(vp_dev->ioaddr + VIRTIO_PCI_STATUS); -} - -static void vp_set_status(struct virtio_device *vdev, u8 status) -{ - struct virtio_pci_device *vp_dev = to_vp_device(vdev); - /* We should never be setting status to 0. */ - BUG_ON(status == 0); - iowrite8(status, vp_dev->ioaddr + VIRTIO_PCI_STATUS); -} - -/* wait for pending irq handlers */ -static void vp_synchronize_vectors(struct virtio_device *vdev) -{ - struct virtio_pci_device *vp_dev = to_vp_device(vdev); - int i; - - if (vp_dev->intx_enabled) - synchronize_irq(vp_dev->pci_dev->irq); - - for (i = 0; i < vp_dev->msix_vectors; ++i) - synchronize_irq(vp_dev->msix_entries[i].vector); -} - -static void vp_reset(struct virtio_device *vdev) -{ - struct virtio_pci_device *vp_dev = to_vp_device(vdev); - /* 0 status means a reset. */ - iowrite8(0, vp_dev->ioaddr + VIRTIO_PCI_STATUS); - /* Flush out the status write, and flush in device writes, - * including MSi-X interrupts, if any. */ - ioread8(vp_dev->ioaddr + VIRTIO_PCI_STATUS); - /* Flush pending VQ/configuration callbacks. */ - vp_synchronize_vectors(vdev); -} - -/* the notify function used when creating a virt queue */ -static void vp_notify(struct virtqueue *vq) -{ - struct virtio_pci_device *vp_dev = to_vp_device(vq->vdev); - - /* we write the queue's selector into the notification register to - * signal the other end */ - iowrite16(vq->index, vp_dev->ioaddr + VIRTIO_PCI_QUEUE_NOTIFY); -} - -/* Handle a configuration change: Tell driver if it wants to know. */ -static irqreturn_t vp_config_changed(int irq, void *opaque) -{ - struct virtio_pci_device *vp_dev = opaque; - struct virtio_driver *drv; - drv = container_of(vp_dev->vdev.dev.driver, - struct virtio_driver, driver); - - if (drv && drv->config_changed) - drv->config_changed(&vp_dev->vdev); - return IRQ_HANDLED; -} - -/* Notify all virtqueues on an interrupt. */ -static irqreturn_t vp_vring_interrupt(int irq, void *opaque) -{ - struct virtio_pci_device *vp_dev = opaque; - struct virtio_pci_vq_info *info; - irqreturn_t ret = IRQ_NONE; - unsigned long flags; - - spin_lock_irqsave(&vp_dev->lock, flags); - list_for_each_entry(info, &vp_dev->virtqueues, node) { - if (vring_interrupt(irq, info->vq) == IRQ_HANDLED) - ret = IRQ_HANDLED; - } - spin_unlock_irqrestore(&vp_dev->lock, flags); - - return ret; -} - -/* A small wrapper to also acknowledge the interrupt when it's handled. - * I really need an EIO hook for the vring so I can ack the interrupt once we - * know that we'll be handling the IRQ but before we invoke the callback since - * the callback may notify the host which results in the host attempting to - * raise an interrupt that we would then mask once we acknowledged the - * interrupt. */ -static irqreturn_t vp_interrupt(int irq, void *opaque) -{ - struct virtio_pci_device *vp_dev = opaque; - u8 isr; - - /* reading the ISR has the effect of also clearing it so it's very - * important to save off the value. */ - isr = ioread8(vp_dev->ioaddr + VIRTIO_PCI_ISR); - - /* It's definitely not us if the ISR was not high */ - if (!isr) - return IRQ_NONE; - - /* Configuration change? Tell driver if it wants to know. */ - if (isr & VIRTIO_PCI_ISR_CONFIG) - vp_config_changed(irq, opaque); - - return vp_vring_interrupt(irq, opaque); -} - -static void vp_free_vectors(struct virtio_device *vdev) -{ - struct virtio_pci_device *vp_dev = to_vp_device(vdev); - int i; - - if (vp_dev->intx_enabled) { - free_irq(vp_dev->pci_dev->irq, vp_dev); - vp_dev->intx_enabled = 0; - } - - for (i = 0; i < vp_dev->msix_used_vectors; ++i) - free_irq(vp_dev->msix_entries[i].vector, vp_dev); - - for (i = 0; i < vp_dev->msix_vectors; i++) - if (vp_dev->msix_affinity_masks[i]) - free_cpumask_var(vp_dev->msix_affinity_masks[i]); - - if (vp_dev->msix_enabled) { - /* Disable the vector used for configuration */ - iowrite16(VIRTIO_MSI_NO_VECTOR, - vp_dev->ioaddr + VIRTIO_MSI_CONFIG_VECTOR); - /* Flush the write out to device */ - ioread16(vp_dev->ioaddr + VIRTIO_MSI_CONFIG_VECTOR); - - pci_disable_msix(vp_dev->pci_dev); - vp_dev->msix_enabled = 0; - } - - vp_dev->msix_vectors = 0; - vp_dev->msix_used_vectors = 0; - kfree(vp_dev->msix_names); - vp_dev->msix_names = NULL; - kfree(vp_dev->msix_entries); - vp_dev->msix_entries = NULL; - kfree(vp_dev->msix_affinity_masks); - vp_dev->msix_affinity_masks = NULL; -} - -static int vp_request_msix_vectors(struct virtio_device *vdev, int nvectors, - bool per_vq_vectors) -{ - struct virtio_pci_device *vp_dev = to_vp_device(vdev); - const char *name = dev_name(&vp_dev->vdev.dev); - unsigned i, v; - int err = -ENOMEM; - - vp_dev->msix_vectors = nvectors; - - vp_dev->msix_entries = kmalloc(nvectors * sizeof *vp_dev->msix_entries, - GFP_KERNEL); - if (!vp_dev->msix_entries) - goto error; - vp_dev->msix_names = kmalloc(nvectors * sizeof *vp_dev->msix_names, - GFP_KERNEL); - if (!vp_dev->msix_names) - goto error; - vp_dev->msix_affinity_masks - = kzalloc(nvectors * sizeof *vp_dev->msix_affinity_masks, - GFP_KERNEL); - if (!vp_dev->msix_affinity_masks) - goto error; - for (i = 0; i < nvectors; ++i) - if (!alloc_cpumask_var(&vp_dev->msix_affinity_masks[i], - GFP_KERNEL)) - goto error; - - for (i = 0; i < nvectors; ++i) - vp_dev->msix_entries[i].entry = i; - - /* pci_enable_msix returns positive if we can't get this many. */ - err = pci_enable_msix(vp_dev->pci_dev, vp_dev->msix_entries, nvectors); - if (err > 0) - err = -ENOSPC; - if (err) - goto error; - vp_dev->msix_enabled = 1; - - /* Set the vector used for configuration */ - v = vp_dev->msix_used_vectors; - snprintf(vp_dev->msix_names[v], sizeof *vp_dev->msix_names, - "%s-config", name); - err = request_irq(vp_dev->msix_entries[v].vector, - vp_config_changed, 0, vp_dev->msix_names[v], - vp_dev); - if (err) - goto error; - ++vp_dev->msix_used_vectors; - - iowrite16(v, vp_dev->ioaddr + VIRTIO_MSI_CONFIG_VECTOR); - /* Verify we had enough resources to assign the vector */ - v = ioread16(vp_dev->ioaddr + VIRTIO_MSI_CONFIG_VECTOR); - if (v == VIRTIO_MSI_NO_VECTOR) { - err = -EBUSY; - goto error; - } - - if (!per_vq_vectors) { - /* Shared vector for all VQs */ - v = vp_dev->msix_used_vectors; - snprintf(vp_dev->msix_names[v], sizeof *vp_dev->msix_names, - "%s-virtqueues", name); - err = request_irq(vp_dev->msix_entries[v].vector, - vp_vring_interrupt, 0, vp_dev->msix_names[v], - vp_dev); - if (err) - goto error; - ++vp_dev->msix_used_vectors; - } - return 0; -error: - vp_free_vectors(vdev); - return err; -} - -static int vp_request_intx(struct virtio_device *vdev) -{ - int err; - struct virtio_pci_device *vp_dev = to_vp_device(vdev); - - err = request_irq(vp_dev->pci_dev->irq, vp_interrupt, - IRQF_SHARED, dev_name(&vdev->dev), vp_dev); - if (!err) - vp_dev->intx_enabled = 1; - return err; -} - -static struct virtqueue *setup_vq(struct virtio_device *vdev, unsigned index, - void (*callback)(struct virtqueue *vq), - const char *name, - u16 msix_vec) -{ - struct virtio_pci_device *vp_dev = to_vp_device(vdev); - struct virtio_pci_vq_info *info; - struct virtqueue *vq; - unsigned long flags, size; - u16 num; - int err; - - /* Select the queue we're interested in */ - iowrite16(index, vp_dev->ioaddr + VIRTIO_PCI_QUEUE_SEL); - - /* Check if queue is either not available or already active. */ - num = ioread16(vp_dev->ioaddr + VIRTIO_PCI_QUEUE_NUM); - if (!num || ioread32(vp_dev->ioaddr + VIRTIO_PCI_QUEUE_PFN)) - return ERR_PTR(-ENOENT); - - /* allocate and fill out our structure the represents an active - * queue */ - info = kmalloc(sizeof(struct virtio_pci_vq_info), GFP_KERNEL); - if (!info) - return ERR_PTR(-ENOMEM); - - info->num = num; - info->msix_vector = msix_vec; - - size = PAGE_ALIGN(vring_size(num, VIRTIO_PCI_VRING_ALIGN)); - info->queue = alloc_pages_exact(size, GFP_KERNEL|__GFP_ZERO); - if (info->queue == NULL) { - err = -ENOMEM; - goto out_info; - } - - /* activate the queue */ - iowrite32(virt_to_phys(info->queue) >> VIRTIO_PCI_QUEUE_ADDR_SHIFT, - vp_dev->ioaddr + VIRTIO_PCI_QUEUE_PFN); - - /* create the vring */ - vq = vring_new_virtqueue(index, info->num, VIRTIO_PCI_VRING_ALIGN, vdev, - true, info->queue, vp_notify, callback, name); - if (!vq) { - err = -ENOMEM; - goto out_activate_queue; - } - - vq->priv = info; - info->vq = vq; - - if (msix_vec != VIRTIO_MSI_NO_VECTOR) { - iowrite16(msix_vec, vp_dev->ioaddr + VIRTIO_MSI_QUEUE_VECTOR); - msix_vec = ioread16(vp_dev->ioaddr + VIRTIO_MSI_QUEUE_VECTOR); - if (msix_vec == VIRTIO_MSI_NO_VECTOR) { - err = -EBUSY; - goto out_assign; - } - } - - if (callback) { - spin_lock_irqsave(&vp_dev->lock, flags); - list_add(&info->node, &vp_dev->virtqueues); - spin_unlock_irqrestore(&vp_dev->lock, flags); - } else { - INIT_LIST_HEAD(&info->node); - } - - return vq; - -out_assign: - vring_del_virtqueue(vq); -out_activate_queue: - iowrite32(0, vp_dev->ioaddr + VIRTIO_PCI_QUEUE_PFN); - free_pages_exact(info->queue, size); -out_info: - kfree(info); - return ERR_PTR(err); -} - -static void vp_del_vq(struct virtqueue *vq) -{ - struct virtio_pci_device *vp_dev = to_vp_device(vq->vdev); - struct virtio_pci_vq_info *info = vq->priv; - unsigned long flags, size; - - spin_lock_irqsave(&vp_dev->lock, flags); - list_del(&info->node); - spin_unlock_irqrestore(&vp_dev->lock, flags); - - iowrite16(vq->index, vp_dev->ioaddr + VIRTIO_PCI_QUEUE_SEL); - - if (vp_dev->msix_enabled) { - iowrite16(VIRTIO_MSI_NO_VECTOR, - vp_dev->ioaddr + VIRTIO_MSI_QUEUE_VECTOR); - /* Flush the write out to device */ - ioread8(vp_dev->ioaddr + VIRTIO_PCI_ISR); - } - - vring_del_virtqueue(vq); - - /* Select and deactivate the queue */ - iowrite32(0, vp_dev->ioaddr + VIRTIO_PCI_QUEUE_PFN); - - size = PAGE_ALIGN(vring_size(info->num, VIRTIO_PCI_VRING_ALIGN)); - free_pages_exact(info->queue, size); - kfree(info); -} - -/* the config->del_vqs() implementation */ -static void vp_del_vqs(struct virtio_device *vdev) -{ - struct virtio_pci_device *vp_dev = to_vp_device(vdev); - struct virtqueue *vq, *n; - struct virtio_pci_vq_info *info; - - list_for_each_entry_safe(vq, n, &vdev->vqs, list) { - info = vq->priv; - if (vp_dev->per_vq_vectors && - info->msix_vector != VIRTIO_MSI_NO_VECTOR) - free_irq(vp_dev->msix_entries[info->msix_vector].vector, - vq); - vp_del_vq(vq); - } - vp_dev->per_vq_vectors = false; - - vp_free_vectors(vdev); -} - -static int vp_try_to_find_vqs(struct virtio_device *vdev, unsigned nvqs, - struct virtqueue *vqs[], - vq_callback_t *callbacks[], - const char *names[], - bool use_msix, - bool per_vq_vectors) -{ - struct virtio_pci_device *vp_dev = to_vp_device(vdev); - u16 msix_vec; - int i, err, nvectors, allocated_vectors; - - if (!use_msix) { - /* Old style: one normal interrupt for change and all vqs. */ - err = vp_request_intx(vdev); - if (err) - goto error_request; - } else { - if (per_vq_vectors) { - /* Best option: one for change interrupt, one per vq. */ - nvectors = 1; - for (i = 0; i < nvqs; ++i) - if (callbacks[i]) - ++nvectors; - } else { - /* Second best: one for change, shared for all vqs. */ - nvectors = 2; - } - - err = vp_request_msix_vectors(vdev, nvectors, per_vq_vectors); - if (err) - goto error_request; - } - - vp_dev->per_vq_vectors = per_vq_vectors; - allocated_vectors = vp_dev->msix_used_vectors; - for (i = 0; i < nvqs; ++i) { - if (!names[i]) { - vqs[i] = NULL; - continue; - } else if (!callbacks[i] || !vp_dev->msix_enabled) - msix_vec = VIRTIO_MSI_NO_VECTOR; - else if (vp_dev->per_vq_vectors) - msix_vec = allocated_vectors++; - else - msix_vec = VP_MSIX_VQ_VECTOR; - vqs[i] = setup_vq(vdev, i, callbacks[i], names[i], msix_vec); - if (IS_ERR(vqs[i])) { - err = PTR_ERR(vqs[i]); - goto error_find; - } - - if (!vp_dev->per_vq_vectors || msix_vec == VIRTIO_MSI_NO_VECTOR) - continue; - - /* allocate per-vq irq if available and necessary */ - snprintf(vp_dev->msix_names[msix_vec], - sizeof *vp_dev->msix_names, - "%s-%s", - dev_name(&vp_dev->vdev.dev), names[i]); - err = request_irq(vp_dev->msix_entries[msix_vec].vector, - vring_interrupt, 0, - vp_dev->msix_names[msix_vec], - vqs[i]); - if (err) { - vp_del_vq(vqs[i]); - goto error_find; - } - } - return 0; - -error_find: - vp_del_vqs(vdev); - -error_request: - return err; -} - -/* the config->find_vqs() implementation */ -static int vp_find_vqs(struct virtio_device *vdev, unsigned nvqs, - struct virtqueue *vqs[], - vq_callback_t *callbacks[], - const char *names[]) -{ - int err; - - /* Try MSI-X with one vector per queue. */ - err = vp_try_to_find_vqs(vdev, nvqs, vqs, callbacks, names, true, true); - if (!err) - return 0; - /* Fallback: MSI-X with one vector for config, one shared for queues. */ - err = vp_try_to_find_vqs(vdev, nvqs, vqs, callbacks, names, - true, false); - if (!err) - return 0; - /* Finally fall back to regular interrupts. */ - return vp_try_to_find_vqs(vdev, nvqs, vqs, callbacks, names, - false, false); -} - -static const char *vp_bus_name(struct virtio_device *vdev) -{ - struct virtio_pci_device *vp_dev = to_vp_device(vdev); - - return pci_name(vp_dev->pci_dev); -} - -/* Setup the affinity for a virtqueue: - * - force the affinity for per vq vector - * - OR over all affinities for shared MSI - * - ignore the affinity request if we're using INTX - */ -static int vp_set_vq_affinity(struct virtqueue *vq, int cpu) -{ - struct virtio_device *vdev = vq->vdev; - struct virtio_pci_device *vp_dev = to_vp_device(vdev); - struct virtio_pci_vq_info *info = vq->priv; - struct cpumask *mask; - unsigned int irq; - - if (!vq->callback) - return -EINVAL; - - if (vp_dev->msix_enabled) { - mask = vp_dev->msix_affinity_masks[info->msix_vector]; - irq = vp_dev->msix_entries[info->msix_vector].vector; - if (cpu == -1) - irq_set_affinity_hint(irq, NULL); - else { - cpumask_set_cpu(cpu, mask); - irq_set_affinity_hint(irq, mask); - } - } - return 0; -} - -static const struct virtio_config_ops virtio_pci_config_ops = { - .get = vp_get, - .set = vp_set, - .get_status = vp_get_status, - .set_status = vp_set_status, - .reset = vp_reset, - .find_vqs = vp_find_vqs, - .del_vqs = vp_del_vqs, - .get_features = vp_get_features, - .finalize_features = vp_finalize_features, - .bus_name = vp_bus_name, - .set_vq_affinity = vp_set_vq_affinity, -}; - -static void virtio_pci_release_dev(struct device *_d) -{ - /* - * No need for a release method as we allocate/free - * all devices together with the pci devices. - * Provide an empty one to avoid getting a warning from core. - */ -} - -/* the PCI probing function */ -static int virtio_pci_probe(struct pci_dev *pci_dev, - const struct pci_device_id *id) -{ - struct virtio_pci_device *vp_dev; - int err; - - /* We only own devices >= 0x1000 and <= 0x103f: leave the rest. */ - if (pci_dev->device < 0x1000 || pci_dev->device > 0x103f) - return -ENODEV; - - if (pci_dev->revision != VIRTIO_PCI_ABI_VERSION) { - printk(KERN_ERR "virtio_pci: expected ABI version %d, got %d\n", - VIRTIO_PCI_ABI_VERSION, pci_dev->revision); - return -ENODEV; - } - - /* allocate our structure and fill it out */ - vp_dev = kzalloc(sizeof(struct virtio_pci_device), GFP_KERNEL); - if (vp_dev == NULL) - return -ENOMEM; - - vp_dev->vdev.dev.parent = &pci_dev->dev; - vp_dev->vdev.dev.release = virtio_pci_release_dev; - vp_dev->vdev.config = &virtio_pci_config_ops; - vp_dev->pci_dev = pci_dev; - INIT_LIST_HEAD(&vp_dev->virtqueues); - spin_lock_init(&vp_dev->lock); - - /* Disable MSI/MSIX to bring device to a known good state. */ - pci_msi_off(pci_dev); - - /* enable the device */ - err = pci_enable_device(pci_dev); - if (err) - goto out; - - err = pci_request_regions(pci_dev, "virtio-pci"); - if (err) - goto out_enable_device; - - vp_dev->ioaddr = pci_iomap(pci_dev, 0, 0); - if (vp_dev->ioaddr == NULL) { - err = -ENOMEM; - goto out_req_regions; - } - - pci_set_drvdata(pci_dev, vp_dev); - pci_set_master(pci_dev); - - /* we use the subsystem vendor/device id as the virtio vendor/device - * id. this allows us to use the same PCI vendor/device id for all - * virtio devices and to identify the particular virtio driver by - * the subsystem ids */ - vp_dev->vdev.id.vendor = pci_dev->subsystem_vendor; - vp_dev->vdev.id.device = pci_dev->subsystem_device; - - /* finally register the virtio device */ - err = register_virtio_device(&vp_dev->vdev); - if (err) - goto out_set_drvdata; - - return 0; - -out_set_drvdata: - pci_set_drvdata(pci_dev, NULL); - pci_iounmap(pci_dev, vp_dev->ioaddr); -out_req_regions: - pci_release_regions(pci_dev); -out_enable_device: - pci_disable_device(pci_dev); -out: - kfree(vp_dev); - return err; -} - -static void virtio_pci_remove(struct pci_dev *pci_dev) -{ - struct virtio_pci_device *vp_dev = pci_get_drvdata(pci_dev); - - unregister_virtio_device(&vp_dev->vdev); - - vp_del_vqs(&vp_dev->vdev); - pci_set_drvdata(pci_dev, NULL); - pci_iounmap(pci_dev, vp_dev->ioaddr); - pci_release_regions(pci_dev); - pci_disable_device(pci_dev); - kfree(vp_dev); -} - -#ifdef CONFIG_PM -static int virtio_pci_freeze(struct device *dev) -{ - struct pci_dev *pci_dev = to_pci_dev(dev); - struct virtio_pci_device *vp_dev = pci_get_drvdata(pci_dev); - struct virtio_driver *drv; - int ret; - - drv = container_of(vp_dev->vdev.dev.driver, - struct virtio_driver, driver); - - ret = 0; - vp_dev->saved_status = vp_get_status(&vp_dev->vdev); - if (drv && drv->freeze) - ret = drv->freeze(&vp_dev->vdev); - - if (!ret) - pci_disable_device(pci_dev); - return ret; -} - -static int virtio_pci_restore(struct device *dev) -{ - struct pci_dev *pci_dev = to_pci_dev(dev); - struct virtio_pci_device *vp_dev = pci_get_drvdata(pci_dev); - struct virtio_driver *drv; - int ret; - - drv = container_of(vp_dev->vdev.dev.driver, - struct virtio_driver, driver); - - ret = pci_enable_device(pci_dev); - if (ret) - return ret; - - pci_set_master(pci_dev); - vp_finalize_features(&vp_dev->vdev); - - if (drv && drv->restore) - ret = drv->restore(&vp_dev->vdev); - - /* Finally, tell the device we're all set */ - if (!ret) - vp_set_status(&vp_dev->vdev, vp_dev->saved_status); - - return ret; -} - -static const struct dev_pm_ops virtio_pci_pm_ops = { - SET_SYSTEM_SLEEP_PM_OPS(virtio_pci_freeze, virtio_pci_restore) -}; -#endif - -static struct pci_driver virtio_pci_driver = { - .name = "virtio-pci", - .id_table = virtio_pci_id_table, - .probe = virtio_pci_probe, - .remove = virtio_pci_remove, -#ifdef CONFIG_PM - .driver.pm = &virtio_pci_pm_ops, -#endif -}; - -module_pci_driver(virtio_pci_driver); diff --git a/drivers/virtio/virtio_pci_admin_legacy_io.c b/drivers/virtio/virtio_pci_admin_legacy_io.c new file mode 100644 index 000000000000..819cfbbc67c3 --- /dev/null +++ b/drivers/virtio/virtio_pci_admin_legacy_io.c @@ -0,0 +1,244 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Copyright (c) 2023, NVIDIA CORPORATION & AFFILIATES. All rights reserved + */ + +#include <linux/virtio_pci_admin.h> +#include "virtio_pci_common.h" + +/* + * virtio_pci_admin_has_legacy_io - Checks whether the legacy IO + * commands are supported + * @dev: VF pci_dev + * + * Returns true on success. + */ +bool virtio_pci_admin_has_legacy_io(struct pci_dev *pdev) +{ + struct virtio_device *virtio_dev = virtio_pci_vf_get_pf_dev(pdev); + struct virtio_pci_device *vp_dev; + + if (!virtio_dev) + return false; + + if (!virtio_has_feature(virtio_dev, VIRTIO_F_ADMIN_VQ)) + return false; + + vp_dev = to_vp_device(virtio_dev); + + if ((vp_dev->admin_vq.supported_cmds & VIRTIO_LEGACY_ADMIN_CMD_BITMAP) == + VIRTIO_LEGACY_ADMIN_CMD_BITMAP) + return true; + return false; +} +EXPORT_SYMBOL_GPL(virtio_pci_admin_has_legacy_io); + +static int virtio_pci_admin_legacy_io_write(struct pci_dev *pdev, u16 opcode, + u8 offset, u8 size, u8 *buf) +{ + struct virtio_device *virtio_dev = virtio_pci_vf_get_pf_dev(pdev); + struct virtio_admin_cmd_legacy_wr_data *data; + struct virtio_admin_cmd cmd = {}; + struct scatterlist data_sg; + int vf_id; + int ret; + + if (!virtio_dev) + return -ENODEV; + + vf_id = pci_iov_vf_id(pdev); + if (vf_id < 0) + return vf_id; + + data = kzalloc(sizeof(*data) + size, GFP_KERNEL); + if (!data) + return -ENOMEM; + + data->offset = offset; + memcpy(data->registers, buf, size); + sg_init_one(&data_sg, data, sizeof(*data) + size); + cmd.opcode = cpu_to_le16(opcode); + cmd.group_type = cpu_to_le16(VIRTIO_ADMIN_GROUP_TYPE_SRIOV); + cmd.group_member_id = cpu_to_le64(vf_id + 1); + cmd.data_sg = &data_sg; + ret = vp_modern_admin_cmd_exec(virtio_dev, &cmd); + + kfree(data); + return ret; +} + +/* + * virtio_pci_admin_legacy_io_write_common - Write legacy common configuration + * of a member device + * @dev: VF pci_dev + * @offset: starting byte offset within the common configuration area to write to + * @size: size of the data to write + * @buf: buffer which holds the data + * + * Note: caller must serialize access for the given device. + * Returns 0 on success, or negative on failure. + */ +int virtio_pci_admin_legacy_common_io_write(struct pci_dev *pdev, u8 offset, + u8 size, u8 *buf) +{ + return virtio_pci_admin_legacy_io_write(pdev, + VIRTIO_ADMIN_CMD_LEGACY_COMMON_CFG_WRITE, + offset, size, buf); +} +EXPORT_SYMBOL_GPL(virtio_pci_admin_legacy_common_io_write); + +/* + * virtio_pci_admin_legacy_io_write_device - Write legacy device configuration + * of a member device + * @dev: VF pci_dev + * @offset: starting byte offset within the device configuration area to write to + * @size: size of the data to write + * @buf: buffer which holds the data + * + * Note: caller must serialize access for the given device. + * Returns 0 on success, or negative on failure. + */ +int virtio_pci_admin_legacy_device_io_write(struct pci_dev *pdev, u8 offset, + u8 size, u8 *buf) +{ + return virtio_pci_admin_legacy_io_write(pdev, + VIRTIO_ADMIN_CMD_LEGACY_DEV_CFG_WRITE, + offset, size, buf); +} +EXPORT_SYMBOL_GPL(virtio_pci_admin_legacy_device_io_write); + +static int virtio_pci_admin_legacy_io_read(struct pci_dev *pdev, u16 opcode, + u8 offset, u8 size, u8 *buf) +{ + struct virtio_device *virtio_dev = virtio_pci_vf_get_pf_dev(pdev); + struct virtio_admin_cmd_legacy_rd_data *data; + struct scatterlist data_sg, result_sg; + struct virtio_admin_cmd cmd = {}; + int vf_id; + int ret; + + if (!virtio_dev) + return -ENODEV; + + vf_id = pci_iov_vf_id(pdev); + if (vf_id < 0) + return vf_id; + + data = kzalloc(sizeof(*data), GFP_KERNEL); + if (!data) + return -ENOMEM; + + data->offset = offset; + sg_init_one(&data_sg, data, sizeof(*data)); + sg_init_one(&result_sg, buf, size); + cmd.opcode = cpu_to_le16(opcode); + cmd.group_type = cpu_to_le16(VIRTIO_ADMIN_GROUP_TYPE_SRIOV); + cmd.group_member_id = cpu_to_le64(vf_id + 1); + cmd.data_sg = &data_sg; + cmd.result_sg = &result_sg; + ret = vp_modern_admin_cmd_exec(virtio_dev, &cmd); + + kfree(data); + return ret; +} + +/* + * virtio_pci_admin_legacy_device_io_read - Read legacy device configuration of + * a member device + * @dev: VF pci_dev + * @offset: starting byte offset within the device configuration area to read from + * @size: size of the data to be read + * @buf: buffer to hold the returned data + * + * Note: caller must serialize access for the given device. + * Returns 0 on success, or negative on failure. + */ +int virtio_pci_admin_legacy_device_io_read(struct pci_dev *pdev, u8 offset, + u8 size, u8 *buf) +{ + return virtio_pci_admin_legacy_io_read(pdev, + VIRTIO_ADMIN_CMD_LEGACY_DEV_CFG_READ, + offset, size, buf); +} +EXPORT_SYMBOL_GPL(virtio_pci_admin_legacy_device_io_read); + +/* + * virtio_pci_admin_legacy_common_io_read - Read legacy common configuration of + * a member device + * @dev: VF pci_dev + * @offset: starting byte offset within the common configuration area to read from + * @size: size of the data to be read + * @buf: buffer to hold the returned data + * + * Note: caller must serialize access for the given device. + * Returns 0 on success, or negative on failure. + */ +int virtio_pci_admin_legacy_common_io_read(struct pci_dev *pdev, u8 offset, + u8 size, u8 *buf) +{ + return virtio_pci_admin_legacy_io_read(pdev, + VIRTIO_ADMIN_CMD_LEGACY_COMMON_CFG_READ, + offset, size, buf); +} +EXPORT_SYMBOL_GPL(virtio_pci_admin_legacy_common_io_read); + +/* + * virtio_pci_admin_legacy_io_notify_info - Read the queue notification + * information for legacy interface + * @dev: VF pci_dev + * @req_bar_flags: requested bar flags + * @bar: on output the BAR number of the owner or member device + * @bar_offset: on output the offset within bar + * + * Returns 0 on success, or negative on failure. + */ +int virtio_pci_admin_legacy_io_notify_info(struct pci_dev *pdev, + u8 req_bar_flags, u8 *bar, + u64 *bar_offset) +{ + struct virtio_device *virtio_dev = virtio_pci_vf_get_pf_dev(pdev); + struct virtio_admin_cmd_notify_info_result *result; + struct virtio_admin_cmd cmd = {}; + struct scatterlist result_sg; + int vf_id; + int ret; + + if (!virtio_dev) + return -ENODEV; + + vf_id = pci_iov_vf_id(pdev); + if (vf_id < 0) + return vf_id; + + result = kzalloc(sizeof(*result), GFP_KERNEL); + if (!result) + return -ENOMEM; + + sg_init_one(&result_sg, result, sizeof(*result)); + cmd.opcode = cpu_to_le16(VIRTIO_ADMIN_CMD_LEGACY_NOTIFY_INFO); + cmd.group_type = cpu_to_le16(VIRTIO_ADMIN_GROUP_TYPE_SRIOV); + cmd.group_member_id = cpu_to_le64(vf_id + 1); + cmd.result_sg = &result_sg; + ret = vp_modern_admin_cmd_exec(virtio_dev, &cmd); + if (!ret) { + struct virtio_admin_cmd_notify_info_data *entry; + int i; + + ret = -ENOENT; + for (i = 0; i < VIRTIO_ADMIN_CMD_MAX_NOTIFY_INFO; i++) { + entry = &result->entries[i]; + if (entry->flags == VIRTIO_ADMIN_CMD_NOTIFY_INFO_FLAGS_END) + break; + if (entry->flags != req_bar_flags) + continue; + *bar = entry->bar; + *bar_offset = le64_to_cpu(entry->offset); + ret = 0; + break; + } + } + + kfree(result); + return ret; +} +EXPORT_SYMBOL_GPL(virtio_pci_admin_legacy_io_notify_info); diff --git a/drivers/virtio/virtio_pci_common.c b/drivers/virtio/virtio_pci_common.c new file mode 100644 index 000000000000..d6d79af44569 --- /dev/null +++ b/drivers/virtio/virtio_pci_common.c @@ -0,0 +1,865 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * Virtio PCI driver - common functionality for all device versions + * + * This module allows virtio devices to be used over a virtual PCI device. + * This can be used with QEMU based VMMs like KVM or Xen. + * + * Copyright IBM Corp. 2007 + * Copyright Red Hat, Inc. 2014 + * + * Authors: + * Anthony Liguori <aliguori@us.ibm.com> + * Rusty Russell <rusty@rustcorp.com.au> + * Michael S. Tsirkin <mst@redhat.com> + */ + +#include "virtio_pci_common.h" + +static bool force_legacy = false; + +#if IS_ENABLED(CONFIG_VIRTIO_PCI_LEGACY) +module_param(force_legacy, bool, 0444); +MODULE_PARM_DESC(force_legacy, + "Force legacy mode for transitional virtio 1 devices"); +#endif + +bool vp_is_avq(struct virtio_device *vdev, unsigned int index) +{ + struct virtio_pci_device *vp_dev = to_vp_device(vdev); + + if (!virtio_has_feature(vdev, VIRTIO_F_ADMIN_VQ)) + return false; + + return index == vp_dev->admin_vq.vq_index; +} + +/* wait for pending irq handlers */ +void vp_synchronize_vectors(struct virtio_device *vdev) +{ + struct virtio_pci_device *vp_dev = to_vp_device(vdev); + int i; + + if (vp_dev->intx_enabled) + synchronize_irq(vp_dev->pci_dev->irq); + + for (i = 0; i < vp_dev->msix_vectors; ++i) + synchronize_irq(pci_irq_vector(vp_dev->pci_dev, i)); +} + +/* the notify function used when creating a virt queue */ +bool vp_notify(struct virtqueue *vq) +{ + /* we write the queue's selector into the notification register to + * signal the other end */ + iowrite16(vq->index, (void __iomem *)vq->priv); + return true; +} + +/* Notify all slow path virtqueues on an interrupt. */ +static void vp_vring_slow_path_interrupt(int irq, + struct virtio_pci_device *vp_dev) +{ + struct virtio_pci_vq_info *info; + unsigned long flags; + + spin_lock_irqsave(&vp_dev->lock, flags); + list_for_each_entry(info, &vp_dev->slow_virtqueues, node) + vring_interrupt(irq, info->vq); + spin_unlock_irqrestore(&vp_dev->lock, flags); +} + +/* Handle a configuration change: Tell driver if it wants to know. */ +static irqreturn_t vp_config_changed(int irq, void *opaque) +{ + struct virtio_pci_device *vp_dev = opaque; + + virtio_config_changed(&vp_dev->vdev); + vp_vring_slow_path_interrupt(irq, vp_dev); + return IRQ_HANDLED; +} + +/* Notify all virtqueues on an interrupt. */ +static irqreturn_t vp_vring_interrupt(int irq, void *opaque) +{ + struct virtio_pci_device *vp_dev = opaque; + struct virtio_pci_vq_info *info; + irqreturn_t ret = IRQ_NONE; + unsigned long flags; + + spin_lock_irqsave(&vp_dev->lock, flags); + list_for_each_entry(info, &vp_dev->virtqueues, node) { + if (vring_interrupt(irq, info->vq) == IRQ_HANDLED) + ret = IRQ_HANDLED; + } + spin_unlock_irqrestore(&vp_dev->lock, flags); + + return ret; +} + +/* A small wrapper to also acknowledge the interrupt when it's handled. + * I really need an EIO hook for the vring so I can ack the interrupt once we + * know that we'll be handling the IRQ but before we invoke the callback since + * the callback may notify the host which results in the host attempting to + * raise an interrupt that we would then mask once we acknowledged the + * interrupt. */ +static irqreturn_t vp_interrupt(int irq, void *opaque) +{ + struct virtio_pci_device *vp_dev = opaque; + u8 isr; + + /* reading the ISR has the effect of also clearing it so it's very + * important to save off the value. */ + isr = ioread8(vp_dev->isr); + + /* It's definitely not us if the ISR was not high */ + if (!isr) + return IRQ_NONE; + + /* Configuration change? Tell driver if it wants to know. */ + if (isr & VIRTIO_PCI_ISR_CONFIG) + vp_config_changed(irq, opaque); + + return vp_vring_interrupt(irq, opaque); +} + +static int vp_request_msix_vectors(struct virtio_device *vdev, int nvectors, + bool per_vq_vectors, struct irq_affinity *desc) +{ + struct virtio_pci_device *vp_dev = to_vp_device(vdev); + const char *name = dev_name(&vp_dev->vdev.dev); + unsigned int flags = PCI_IRQ_MSIX; + unsigned int i, v; + int err = -ENOMEM; + + vp_dev->msix_vectors = nvectors; + + vp_dev->msix_names = kmalloc_array(nvectors, + sizeof(*vp_dev->msix_names), + GFP_KERNEL); + if (!vp_dev->msix_names) + goto error; + vp_dev->msix_affinity_masks + = kcalloc(nvectors, sizeof(*vp_dev->msix_affinity_masks), + GFP_KERNEL); + if (!vp_dev->msix_affinity_masks) + goto error; + for (i = 0; i < nvectors; ++i) + if (!alloc_cpumask_var(&vp_dev->msix_affinity_masks[i], + GFP_KERNEL)) + goto error; + + if (!per_vq_vectors) + desc = NULL; + + if (desc) { + flags |= PCI_IRQ_AFFINITY; + desc->pre_vectors++; /* virtio config vector */ + } + + err = pci_alloc_irq_vectors_affinity(vp_dev->pci_dev, nvectors, + nvectors, flags, desc); + if (err < 0) + goto error; + vp_dev->msix_enabled = 1; + + /* Set the vector used for configuration */ + v = vp_dev->msix_used_vectors; + snprintf(vp_dev->msix_names[v], sizeof *vp_dev->msix_names, + "%s-config", name); + err = request_irq(pci_irq_vector(vp_dev->pci_dev, v), + vp_config_changed, 0, vp_dev->msix_names[v], + vp_dev); + if (err) + goto error; + ++vp_dev->msix_used_vectors; + + v = vp_dev->config_vector(vp_dev, v); + /* Verify we had enough resources to assign the vector */ + if (v == VIRTIO_MSI_NO_VECTOR) { + err = -EBUSY; + goto error; + } + + if (!per_vq_vectors) { + /* Shared vector for all VQs */ + v = vp_dev->msix_used_vectors; + snprintf(vp_dev->msix_names[v], sizeof *vp_dev->msix_names, + "%s-virtqueues", name); + err = request_irq(pci_irq_vector(vp_dev->pci_dev, v), + vp_vring_interrupt, 0, vp_dev->msix_names[v], + vp_dev); + if (err) + goto error; + ++vp_dev->msix_used_vectors; + } + return 0; +error: + return err; +} + +static bool vp_is_slow_path_vector(u16 msix_vec) +{ + return msix_vec == VP_MSIX_CONFIG_VECTOR; +} + +static struct virtqueue *vp_setup_vq(struct virtio_device *vdev, unsigned int index, + void (*callback)(struct virtqueue *vq), + const char *name, + bool ctx, + u16 msix_vec, + struct virtio_pci_vq_info **p_info) +{ + struct virtio_pci_device *vp_dev = to_vp_device(vdev); + struct virtio_pci_vq_info *info = kmalloc(sizeof *info, GFP_KERNEL); + struct virtqueue *vq; + unsigned long flags; + + /* fill out our structure that represents an active queue */ + if (!info) + return ERR_PTR(-ENOMEM); + + vq = vp_dev->setup_vq(vp_dev, info, index, callback, name, ctx, + msix_vec); + if (IS_ERR(vq)) + goto out_info; + + info->vq = vq; + if (callback) { + spin_lock_irqsave(&vp_dev->lock, flags); + if (!vp_is_slow_path_vector(msix_vec)) + list_add(&info->node, &vp_dev->virtqueues); + else + list_add(&info->node, &vp_dev->slow_virtqueues); + spin_unlock_irqrestore(&vp_dev->lock, flags); + } else { + INIT_LIST_HEAD(&info->node); + } + + *p_info = info; + return vq; + +out_info: + kfree(info); + return vq; +} + +static void vp_del_vq(struct virtqueue *vq, struct virtio_pci_vq_info *info) +{ + struct virtio_pci_device *vp_dev = to_vp_device(vq->vdev); + unsigned long flags; + + /* + * If it fails during re-enable reset vq. This way we won't rejoin + * info->node to the queue. Prevent unexpected irqs. + */ + if (!vq->reset) { + spin_lock_irqsave(&vp_dev->lock, flags); + list_del(&info->node); + spin_unlock_irqrestore(&vp_dev->lock, flags); + } + + vp_dev->del_vq(info); + kfree(info); +} + +/* the config->del_vqs() implementation */ +void vp_del_vqs(struct virtio_device *vdev) +{ + struct virtio_pci_device *vp_dev = to_vp_device(vdev); + struct virtio_pci_vq_info *info; + struct virtqueue *vq, *n; + int i; + + list_for_each_entry_safe(vq, n, &vdev->vqs, list) { + info = vp_is_avq(vdev, vq->index) ? vp_dev->admin_vq.info : + vp_dev->vqs[vq->index]; + + if (vp_dev->per_vq_vectors) { + int v = info->msix_vector; + if (v != VIRTIO_MSI_NO_VECTOR && + !vp_is_slow_path_vector(v)) { + int irq = pci_irq_vector(vp_dev->pci_dev, v); + + irq_update_affinity_hint(irq, NULL); + free_irq(irq, vq); + } + } + vp_del_vq(vq, info); + } + vp_dev->per_vq_vectors = false; + + if (vp_dev->intx_enabled) { + free_irq(vp_dev->pci_dev->irq, vp_dev); + vp_dev->intx_enabled = 0; + } + + for (i = 0; i < vp_dev->msix_used_vectors; ++i) + free_irq(pci_irq_vector(vp_dev->pci_dev, i), vp_dev); + + if (vp_dev->msix_affinity_masks) { + for (i = 0; i < vp_dev->msix_vectors; i++) + free_cpumask_var(vp_dev->msix_affinity_masks[i]); + } + + if (vp_dev->msix_enabled) { + /* Disable the vector used for configuration */ + vp_dev->config_vector(vp_dev, VIRTIO_MSI_NO_VECTOR); + + pci_free_irq_vectors(vp_dev->pci_dev); + vp_dev->msix_enabled = 0; + } + + vp_dev->msix_vectors = 0; + vp_dev->msix_used_vectors = 0; + kfree(vp_dev->msix_names); + vp_dev->msix_names = NULL; + kfree(vp_dev->msix_affinity_masks); + vp_dev->msix_affinity_masks = NULL; + kfree(vp_dev->vqs); + vp_dev->vqs = NULL; +} + +enum vp_vq_vector_policy { + VP_VQ_VECTOR_POLICY_EACH, + VP_VQ_VECTOR_POLICY_SHARED_SLOW, + VP_VQ_VECTOR_POLICY_SHARED, +}; + +static struct virtqueue * +vp_find_one_vq_msix(struct virtio_device *vdev, int queue_idx, + vq_callback_t *callback, const char *name, bool ctx, + bool slow_path, int *allocated_vectors, + enum vp_vq_vector_policy vector_policy, + struct virtio_pci_vq_info **p_info) +{ + struct virtio_pci_device *vp_dev = to_vp_device(vdev); + struct virtqueue *vq; + u16 msix_vec; + int err; + + if (!callback) + msix_vec = VIRTIO_MSI_NO_VECTOR; + else if (vector_policy == VP_VQ_VECTOR_POLICY_EACH || + (vector_policy == VP_VQ_VECTOR_POLICY_SHARED_SLOW && + !slow_path)) + msix_vec = (*allocated_vectors)++; + else if (vector_policy != VP_VQ_VECTOR_POLICY_EACH && + slow_path) + msix_vec = VP_MSIX_CONFIG_VECTOR; + else + msix_vec = VP_MSIX_VQ_VECTOR; + vq = vp_setup_vq(vdev, queue_idx, callback, name, ctx, msix_vec, + p_info); + if (IS_ERR(vq)) + return vq; + + if (vector_policy == VP_VQ_VECTOR_POLICY_SHARED || + msix_vec == VIRTIO_MSI_NO_VECTOR || + vp_is_slow_path_vector(msix_vec)) + return vq; + + /* allocate per-vq irq if available and necessary */ + snprintf(vp_dev->msix_names[msix_vec], sizeof(*vp_dev->msix_names), + "%s-%s", dev_name(&vp_dev->vdev.dev), name); + err = request_irq(pci_irq_vector(vp_dev->pci_dev, msix_vec), + vring_interrupt, 0, + vp_dev->msix_names[msix_vec], vq); + if (err) { + vp_del_vq(vq, *p_info); + return ERR_PTR(err); + } + + return vq; +} + +static int vp_find_vqs_msix(struct virtio_device *vdev, unsigned int nvqs, + struct virtqueue *vqs[], + struct virtqueue_info vqs_info[], + enum vp_vq_vector_policy vector_policy, + struct irq_affinity *desc) +{ + struct virtio_pci_device *vp_dev = to_vp_device(vdev); + struct virtio_pci_admin_vq *avq = &vp_dev->admin_vq; + struct virtqueue_info *vqi; + int i, err, nvectors, allocated_vectors, queue_idx = 0; + struct virtqueue *vq; + bool per_vq_vectors; + u16 avq_num = 0; + + vp_dev->vqs = kcalloc(nvqs, sizeof(*vp_dev->vqs), GFP_KERNEL); + if (!vp_dev->vqs) + return -ENOMEM; + + if (vp_dev->avq_index) { + err = vp_dev->avq_index(vdev, &avq->vq_index, &avq_num); + if (err) + goto error_find; + } + + per_vq_vectors = vector_policy != VP_VQ_VECTOR_POLICY_SHARED; + + if (per_vq_vectors) { + /* Best option: one for change interrupt, one per vq. */ + nvectors = 1; + for (i = 0; i < nvqs; ++i) { + vqi = &vqs_info[i]; + if (vqi->name && vqi->callback) + ++nvectors; + } + if (avq_num && vector_policy == VP_VQ_VECTOR_POLICY_EACH) + ++nvectors; + } else { + /* Second best: one for change, shared for all vqs. */ + nvectors = 2; + } + + err = vp_request_msix_vectors(vdev, nvectors, per_vq_vectors, desc); + if (err) + goto error_find; + + vp_dev->per_vq_vectors = per_vq_vectors; + allocated_vectors = vp_dev->msix_used_vectors; + for (i = 0; i < nvqs; ++i) { + vqi = &vqs_info[i]; + if (!vqi->name) { + vqs[i] = NULL; + continue; + } + vqs[i] = vp_find_one_vq_msix(vdev, queue_idx++, vqi->callback, + vqi->name, vqi->ctx, false, + &allocated_vectors, vector_policy, + &vp_dev->vqs[i]); + if (IS_ERR(vqs[i])) { + err = PTR_ERR(vqs[i]); + goto error_find; + } + } + + if (!avq_num) + return 0; + sprintf(avq->name, "avq.%u", avq->vq_index); + vq = vp_find_one_vq_msix(vdev, avq->vq_index, vp_modern_avq_done, + avq->name, false, true, &allocated_vectors, + vector_policy, &vp_dev->admin_vq.info); + if (IS_ERR(vq)) { + err = PTR_ERR(vq); + goto error_find; + } + + return 0; + +error_find: + vp_del_vqs(vdev); + return err; +} + +static int vp_find_vqs_intx(struct virtio_device *vdev, unsigned int nvqs, + struct virtqueue *vqs[], + struct virtqueue_info vqs_info[]) +{ + struct virtio_pci_device *vp_dev = to_vp_device(vdev); + struct virtio_pci_admin_vq *avq = &vp_dev->admin_vq; + int i, err, queue_idx = 0; + struct virtqueue *vq; + u16 avq_num = 0; + + vp_dev->vqs = kcalloc(nvqs, sizeof(*vp_dev->vqs), GFP_KERNEL); + if (!vp_dev->vqs) + return -ENOMEM; + + if (vp_dev->avq_index) { + err = vp_dev->avq_index(vdev, &avq->vq_index, &avq_num); + if (err) + goto out_del_vqs; + } + + err = request_irq(vp_dev->pci_dev->irq, vp_interrupt, IRQF_SHARED, + dev_name(&vdev->dev), vp_dev); + if (err) + goto out_del_vqs; + + vp_dev->intx_enabled = 1; + vp_dev->per_vq_vectors = false; + for (i = 0; i < nvqs; ++i) { + struct virtqueue_info *vqi = &vqs_info[i]; + + if (!vqi->name) { + vqs[i] = NULL; + continue; + } + vqs[i] = vp_setup_vq(vdev, queue_idx++, vqi->callback, + vqi->name, vqi->ctx, + VIRTIO_MSI_NO_VECTOR, &vp_dev->vqs[i]); + if (IS_ERR(vqs[i])) { + err = PTR_ERR(vqs[i]); + goto out_del_vqs; + } + } + + if (!avq_num) + return 0; + sprintf(avq->name, "avq.%u", avq->vq_index); + vq = vp_setup_vq(vdev, queue_idx++, vp_modern_avq_done, avq->name, + false, VIRTIO_MSI_NO_VECTOR, + &vp_dev->admin_vq.info); + if (IS_ERR(vq)) { + err = PTR_ERR(vq); + goto out_del_vqs; + } + + return 0; +out_del_vqs: + vp_del_vqs(vdev); + return err; +} + +/* the config->find_vqs() implementation */ +int vp_find_vqs(struct virtio_device *vdev, unsigned int nvqs, + struct virtqueue *vqs[], struct virtqueue_info vqs_info[], + struct irq_affinity *desc) +{ + int err; + + /* Try MSI-X with one vector per queue. */ + err = vp_find_vqs_msix(vdev, nvqs, vqs, vqs_info, + VP_VQ_VECTOR_POLICY_EACH, desc); + if (!err) + return 0; + /* Fallback: MSI-X with one shared vector for config and + * slow path queues, one vector per queue for the rest. + */ + err = vp_find_vqs_msix(vdev, nvqs, vqs, vqs_info, + VP_VQ_VECTOR_POLICY_SHARED_SLOW, desc); + if (!err) + return 0; + /* Fallback: MSI-X with one vector for config, one shared for queues. */ + err = vp_find_vqs_msix(vdev, nvqs, vqs, vqs_info, + VP_VQ_VECTOR_POLICY_SHARED, desc); + if (!err) + return 0; + /* Is there an interrupt? If not give up. */ + if (!(to_vp_device(vdev)->pci_dev->irq)) + return err; + /* Finally fall back to regular interrupts. */ + return vp_find_vqs_intx(vdev, nvqs, vqs, vqs_info); +} + +const char *vp_bus_name(struct virtio_device *vdev) +{ + struct virtio_pci_device *vp_dev = to_vp_device(vdev); + + return pci_name(vp_dev->pci_dev); +} + +/* Setup the affinity for a virtqueue: + * - force the affinity for per vq vector + * - OR over all affinities for shared MSI + * - ignore the affinity request if we're using INTX + */ +int vp_set_vq_affinity(struct virtqueue *vq, const struct cpumask *cpu_mask) +{ + struct virtio_device *vdev = vq->vdev; + struct virtio_pci_device *vp_dev = to_vp_device(vdev); + struct virtio_pci_vq_info *info = vp_dev->vqs[vq->index]; + struct cpumask *mask; + unsigned int irq; + + if (!vq->callback) + return -EINVAL; + + if (vp_dev->msix_enabled) { + mask = vp_dev->msix_affinity_masks[info->msix_vector]; + irq = pci_irq_vector(vp_dev->pci_dev, info->msix_vector); + if (!cpu_mask) + irq_update_affinity_hint(irq, NULL); + else { + cpumask_copy(mask, cpu_mask); + irq_set_affinity_and_hint(irq, mask); + } + } + return 0; +} + +const struct cpumask *vp_get_vq_affinity(struct virtio_device *vdev, int index) +{ + struct virtio_pci_device *vp_dev = to_vp_device(vdev); + + if (!vp_dev->per_vq_vectors || + vp_dev->vqs[index]->msix_vector == VIRTIO_MSI_NO_VECTOR || + vp_is_slow_path_vector(vp_dev->vqs[index]->msix_vector)) + return NULL; + + return pci_irq_get_affinity(vp_dev->pci_dev, + vp_dev->vqs[index]->msix_vector); +} + +#ifdef CONFIG_PM_SLEEP +static int virtio_pci_freeze(struct device *dev) +{ + struct pci_dev *pci_dev = to_pci_dev(dev); + struct virtio_pci_device *vp_dev = pci_get_drvdata(pci_dev); + int ret; + + ret = virtio_device_freeze(&vp_dev->vdev); + + if (!ret) + pci_disable_device(pci_dev); + return ret; +} + +static int virtio_pci_restore(struct device *dev) +{ + struct pci_dev *pci_dev = to_pci_dev(dev); + struct virtio_pci_device *vp_dev = pci_get_drvdata(pci_dev); + int ret; + + ret = pci_enable_device(pci_dev); + if (ret) + return ret; + + pci_set_master(pci_dev); + return virtio_device_restore(&vp_dev->vdev); +} + +static bool vp_supports_pm_no_reset(struct device *dev) +{ + struct pci_dev *pci_dev = to_pci_dev(dev); + u16 pmcsr; + + if (!pci_dev->pm_cap) + return false; + + pci_read_config_word(pci_dev, pci_dev->pm_cap + PCI_PM_CTRL, &pmcsr); + if (PCI_POSSIBLE_ERROR(pmcsr)) { + dev_err(dev, "Unable to query pmcsr"); + return false; + } + + return pmcsr & PCI_PM_CTRL_NO_SOFT_RESET; +} + +static int virtio_pci_suspend(struct device *dev) +{ + return vp_supports_pm_no_reset(dev) ? 0 : virtio_pci_freeze(dev); +} + +static int virtio_pci_resume(struct device *dev) +{ + return vp_supports_pm_no_reset(dev) ? 0 : virtio_pci_restore(dev); +} + +static const struct dev_pm_ops virtio_pci_pm_ops = { + .suspend = virtio_pci_suspend, + .resume = virtio_pci_resume, + .freeze = virtio_pci_freeze, + .thaw = virtio_pci_restore, + .poweroff = virtio_pci_freeze, + .restore = virtio_pci_restore, +}; +#endif + + +/* Qumranet donated their vendor ID for devices 0x1000 thru 0x10FF. */ +static const struct pci_device_id virtio_pci_id_table[] = { + { PCI_DEVICE(PCI_VENDOR_ID_REDHAT_QUMRANET, PCI_ANY_ID) }, + { 0 } +}; + +MODULE_DEVICE_TABLE(pci, virtio_pci_id_table); + +static void virtio_pci_release_dev(struct device *_d) +{ + struct virtio_device *vdev = dev_to_virtio(_d); + struct virtio_pci_device *vp_dev = to_vp_device(vdev); + + /* As struct device is a kobject, it's not safe to + * free the memory (including the reference counter itself) + * until it's release callback. */ + kfree(vp_dev); +} + +static int virtio_pci_probe(struct pci_dev *pci_dev, + const struct pci_device_id *id) +{ + struct virtio_pci_device *vp_dev, *reg_dev = NULL; + int rc; + + /* allocate our structure and fill it out */ + vp_dev = kzalloc(sizeof(struct virtio_pci_device), GFP_KERNEL); + if (!vp_dev) + return -ENOMEM; + + pci_set_drvdata(pci_dev, vp_dev); + vp_dev->vdev.dev.parent = &pci_dev->dev; + vp_dev->vdev.dev.release = virtio_pci_release_dev; + vp_dev->pci_dev = pci_dev; + INIT_LIST_HEAD(&vp_dev->virtqueues); + INIT_LIST_HEAD(&vp_dev->slow_virtqueues); + spin_lock_init(&vp_dev->lock); + + /* enable the device */ + rc = pci_enable_device(pci_dev); + if (rc) + goto err_enable_device; + + if (force_legacy) { + rc = virtio_pci_legacy_probe(vp_dev); + /* Also try modern mode if we can't map BAR0 (no IO space). */ + if (rc == -ENODEV || rc == -ENOMEM) + rc = virtio_pci_modern_probe(vp_dev); + if (rc) + goto err_probe; + } else { + rc = virtio_pci_modern_probe(vp_dev); + if (rc == -ENODEV) + rc = virtio_pci_legacy_probe(vp_dev); + if (rc) + goto err_probe; + } + + pci_set_master(pci_dev); + + rc = register_virtio_device(&vp_dev->vdev); + reg_dev = vp_dev; + if (rc) + goto err_register; + + return 0; + +err_register: + if (vp_dev->is_legacy) + virtio_pci_legacy_remove(vp_dev); + else + virtio_pci_modern_remove(vp_dev); +err_probe: + pci_disable_device(pci_dev); +err_enable_device: + if (reg_dev) + put_device(&vp_dev->vdev.dev); + else + kfree(vp_dev); + return rc; +} + +static void virtio_pci_remove(struct pci_dev *pci_dev) +{ + struct virtio_pci_device *vp_dev = pci_get_drvdata(pci_dev); + struct device *dev = get_device(&vp_dev->vdev.dev); + + /* + * Device is marked broken on surprise removal so that virtio upper + * layers can abort any ongoing operation. + */ + if (!pci_device_is_present(pci_dev)) + virtio_break_device(&vp_dev->vdev); + + pci_disable_sriov(pci_dev); + + unregister_virtio_device(&vp_dev->vdev); + + if (vp_dev->is_legacy) + virtio_pci_legacy_remove(vp_dev); + else + virtio_pci_modern_remove(vp_dev); + + pci_disable_device(pci_dev); + put_device(dev); +} + +static int virtio_pci_sriov_configure(struct pci_dev *pci_dev, int num_vfs) +{ + struct virtio_pci_device *vp_dev = pci_get_drvdata(pci_dev); + struct virtio_device *vdev = &vp_dev->vdev; + int ret; + + if (!(vdev->config->get_status(vdev) & VIRTIO_CONFIG_S_DRIVER_OK)) + return -EBUSY; + + if (!__virtio_test_bit(vdev, VIRTIO_F_SR_IOV)) + return -EINVAL; + + if (pci_vfs_assigned(pci_dev)) + return -EPERM; + + if (num_vfs == 0) { + pci_disable_sriov(pci_dev); + return 0; + } + + ret = pci_enable_sriov(pci_dev, num_vfs); + if (ret < 0) + return ret; + + return num_vfs; +} + +static void virtio_pci_reset_prepare(struct pci_dev *pci_dev) +{ + struct virtio_pci_device *vp_dev = pci_get_drvdata(pci_dev); + int ret = 0; + + ret = virtio_device_reset_prepare(&vp_dev->vdev); + if (ret) { + if (ret != -EOPNOTSUPP) + dev_warn(&pci_dev->dev, "Reset prepare failure: %d", + ret); + return; + } + + if (pci_is_enabled(pci_dev)) + pci_disable_device(pci_dev); +} + +static void virtio_pci_reset_done(struct pci_dev *pci_dev) +{ + struct virtio_pci_device *vp_dev = pci_get_drvdata(pci_dev); + int ret; + + if (pci_is_enabled(pci_dev)) + return; + + ret = pci_enable_device(pci_dev); + if (!ret) { + pci_set_master(pci_dev); + ret = virtio_device_reset_done(&vp_dev->vdev); + } + + if (ret && ret != -EOPNOTSUPP) + dev_warn(&pci_dev->dev, "Reset done failure: %d", ret); +} + +static const struct pci_error_handlers virtio_pci_err_handler = { + .reset_prepare = virtio_pci_reset_prepare, + .reset_done = virtio_pci_reset_done, +}; + +static struct pci_driver virtio_pci_driver = { + .name = "virtio-pci", + .id_table = virtio_pci_id_table, + .probe = virtio_pci_probe, + .remove = virtio_pci_remove, +#ifdef CONFIG_PM_SLEEP + .driver.pm = &virtio_pci_pm_ops, +#endif + .sriov_configure = virtio_pci_sriov_configure, + .err_handler = &virtio_pci_err_handler, +}; + +struct virtio_device *virtio_pci_vf_get_pf_dev(struct pci_dev *pdev) +{ + struct virtio_pci_device *pf_vp_dev; + + pf_vp_dev = pci_iov_get_pf_drvdata(pdev, &virtio_pci_driver); + if (IS_ERR(pf_vp_dev)) + return NULL; + + return &pf_vp_dev->vdev; +} + +module_pci_driver(virtio_pci_driver); + +MODULE_AUTHOR("Anthony Liguori <aliguori@us.ibm.com>"); +MODULE_DESCRIPTION("virtio-pci"); +MODULE_LICENSE("GPL"); +MODULE_VERSION("1"); diff --git a/drivers/virtio/virtio_pci_common.h b/drivers/virtio/virtio_pci_common.h new file mode 100644 index 000000000000..8cd01de27baf --- /dev/null +++ b/drivers/virtio/virtio_pci_common.h @@ -0,0 +1,201 @@ +/* SPDX-License-Identifier: GPL-2.0-or-later */ +#ifndef _DRIVERS_VIRTIO_VIRTIO_PCI_COMMON_H +#define _DRIVERS_VIRTIO_VIRTIO_PCI_COMMON_H +/* + * Virtio PCI driver - APIs for common functionality for all device versions + * + * This module allows virtio devices to be used over a virtual PCI device. + * This can be used with QEMU based VMMs like KVM or Xen. + * + * Copyright IBM Corp. 2007 + * Copyright Red Hat, Inc. 2014 + * + * Authors: + * Anthony Liguori <aliguori@us.ibm.com> + * Rusty Russell <rusty@rustcorp.com.au> + * Michael S. Tsirkin <mst@redhat.com> + */ + +#include <linux/module.h> +#include <linux/list.h> +#include <linux/pci.h> +#include <linux/slab.h> +#include <linux/interrupt.h> +#include <linux/virtio.h> +#include <linux/virtio_config.h> +#include <linux/virtio_ring.h> +#include <linux/virtio_pci.h> +#include <linux/virtio_pci_legacy.h> +#include <linux/virtio_pci_modern.h> +#include <linux/highmem.h> +#include <linux/spinlock.h> +#include <linux/mutex.h> + +struct virtio_pci_vq_info { + /* the actual virtqueue */ + struct virtqueue *vq; + + /* the list node for the virtqueues or slow_virtqueues list */ + struct list_head node; + + /* MSI-X vector (or none) */ + unsigned int msix_vector; +}; + +struct virtio_pci_admin_vq { + /* Virtqueue info associated with this admin queue. */ + struct virtio_pci_vq_info *info; + /* Protects virtqueue access. */ + spinlock_t lock; + u64 supported_cmds; + u64 supported_caps; + u8 max_dev_parts_objects; + struct ida dev_parts_ida; + /* Name of the admin queue: avq.$vq_index. */ + char name[10]; + u16 vq_index; +}; + +/* Our device structure */ +struct virtio_pci_device { + struct virtio_device vdev; + struct pci_dev *pci_dev; + union { + struct virtio_pci_legacy_device ldev; + struct virtio_pci_modern_device mdev; + }; + bool is_legacy; + + /* Where to read and clear interrupt */ + u8 __iomem *isr; + + /* Lists of queues and potentially slow path queues + * so we can dispatch IRQs. + */ + spinlock_t lock; + struct list_head virtqueues; + struct list_head slow_virtqueues; + + /* Array of all virtqueues reported in the + * PCI common config num_queues field + */ + struct virtio_pci_vq_info **vqs; + + struct virtio_pci_admin_vq admin_vq; + + /* MSI-X support */ + int msix_enabled; + int intx_enabled; + cpumask_var_t *msix_affinity_masks; + /* Name strings for interrupts. This size should be enough, + * and I'm too lazy to allocate each name separately. */ + char (*msix_names)[256]; + /* Number of available vectors */ + unsigned int msix_vectors; + /* Vectors allocated, excluding per-vq vectors if any */ + unsigned int msix_used_vectors; + + /* Whether we have vector per vq */ + bool per_vq_vectors; + + struct virtqueue *(*setup_vq)(struct virtio_pci_device *vp_dev, + struct virtio_pci_vq_info *info, + unsigned int idx, + void (*callback)(struct virtqueue *vq), + const char *name, + bool ctx, + u16 msix_vec); + void (*del_vq)(struct virtio_pci_vq_info *info); + + u16 (*config_vector)(struct virtio_pci_device *vp_dev, u16 vector); + int (*avq_index)(struct virtio_device *vdev, u16 *index, u16 *num); +}; + +/* Constants for MSI-X */ +/* Use first vector for configuration changes, second and the rest for + * virtqueues Thus, we need at least 2 vectors for MSI. */ +enum { + VP_MSIX_CONFIG_VECTOR = 0, + VP_MSIX_VQ_VECTOR = 1, +}; + +/* Convert a generic virtio device to our structure */ +static struct virtio_pci_device *to_vp_device(struct virtio_device *vdev) +{ + return container_of(vdev, struct virtio_pci_device, vdev); +} + +/* wait for pending irq handlers */ +void vp_synchronize_vectors(struct virtio_device *vdev); +/* the notify function used when creating a virt queue */ +bool vp_notify(struct virtqueue *vq); +/* the config->del_vqs() implementation */ +void vp_del_vqs(struct virtio_device *vdev); +/* the config->find_vqs() implementation */ +int vp_find_vqs(struct virtio_device *vdev, unsigned int nvqs, + struct virtqueue *vqs[], struct virtqueue_info vqs_info[], + struct irq_affinity *desc); +const char *vp_bus_name(struct virtio_device *vdev); + +/* Setup the affinity for a virtqueue: + * - force the affinity for per vq vector + * - OR over all affinities for shared MSI + * - ignore the affinity request if we're using INTX + */ +int vp_set_vq_affinity(struct virtqueue *vq, const struct cpumask *cpu_mask); + +const struct cpumask *vp_get_vq_affinity(struct virtio_device *vdev, int index); + +#if IS_ENABLED(CONFIG_VIRTIO_PCI_LEGACY) +int virtio_pci_legacy_probe(struct virtio_pci_device *); +void virtio_pci_legacy_remove(struct virtio_pci_device *); +#else +static inline int virtio_pci_legacy_probe(struct virtio_pci_device *vp_dev) +{ + return -ENODEV; +} +static inline void virtio_pci_legacy_remove(struct virtio_pci_device *vp_dev) +{ +} +#endif +int virtio_pci_modern_probe(struct virtio_pci_device *); +void virtio_pci_modern_remove(struct virtio_pci_device *); + +struct virtio_device *virtio_pci_vf_get_pf_dev(struct pci_dev *pdev); + +#define VIRTIO_LEGACY_ADMIN_CMD_BITMAP \ + (BIT_ULL(VIRTIO_ADMIN_CMD_LEGACY_COMMON_CFG_WRITE) | \ + BIT_ULL(VIRTIO_ADMIN_CMD_LEGACY_COMMON_CFG_READ) | \ + BIT_ULL(VIRTIO_ADMIN_CMD_LEGACY_DEV_CFG_WRITE) | \ + BIT_ULL(VIRTIO_ADMIN_CMD_LEGACY_DEV_CFG_READ) | \ + BIT_ULL(VIRTIO_ADMIN_CMD_LEGACY_NOTIFY_INFO)) + +#define VIRTIO_DEV_PARTS_ADMIN_CMD_BITMAP \ + (BIT_ULL(VIRTIO_ADMIN_CMD_CAP_ID_LIST_QUERY) | \ + BIT_ULL(VIRTIO_ADMIN_CMD_DRIVER_CAP_SET) | \ + BIT_ULL(VIRTIO_ADMIN_CMD_DEVICE_CAP_GET) | \ + BIT_ULL(VIRTIO_ADMIN_CMD_RESOURCE_OBJ_CREATE) | \ + BIT_ULL(VIRTIO_ADMIN_CMD_RESOURCE_OBJ_DESTROY) | \ + BIT_ULL(VIRTIO_ADMIN_CMD_DEV_PARTS_METADATA_GET) | \ + BIT_ULL(VIRTIO_ADMIN_CMD_DEV_PARTS_GET) | \ + BIT_ULL(VIRTIO_ADMIN_CMD_DEV_PARTS_SET) | \ + BIT_ULL(VIRTIO_ADMIN_CMD_DEV_MODE_SET)) + +/* Unlike modern drivers which support hardware virtio devices, legacy drivers + * assume software-based devices: e.g. they don't use proper memory barriers + * on ARM, use big endian on PPC, etc. X86 drivers are mostly ok though, more + * or less by chance. For now, only support legacy IO on X86. + */ +#ifdef CONFIG_VIRTIO_PCI_ADMIN_LEGACY +#define VIRTIO_ADMIN_CMD_BITMAP (VIRTIO_LEGACY_ADMIN_CMD_BITMAP | \ + VIRTIO_DEV_PARTS_ADMIN_CMD_BITMAP) +#else +#define VIRTIO_ADMIN_CMD_BITMAP VIRTIO_DEV_PARTS_ADMIN_CMD_BITMAP +#endif + +bool vp_is_avq(struct virtio_device *vdev, unsigned int index); +void vp_modern_avq_done(struct virtqueue *vq); +int vp_modern_admin_cmd_exec(struct virtio_device *vdev, + struct virtio_admin_cmd *cmd); + +#endif diff --git a/drivers/virtio/virtio_pci_legacy.c b/drivers/virtio/virtio_pci_legacy.c new file mode 100644 index 000000000000..d9cbb02b35a1 --- /dev/null +++ b/drivers/virtio/virtio_pci_legacy.c @@ -0,0 +1,236 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * Virtio PCI driver - legacy device support + * + * This module allows virtio devices to be used over a virtual PCI device. + * This can be used with QEMU based VMMs like KVM or Xen. + * + * Copyright IBM Corp. 2007 + * Copyright Red Hat, Inc. 2014 + * + * Authors: + * Anthony Liguori <aliguori@us.ibm.com> + * Rusty Russell <rusty@rustcorp.com.au> + * Michael S. Tsirkin <mst@redhat.com> + */ + +#include "linux/virtio_pci_legacy.h" +#include "virtio_pci_common.h" + +/* virtio config->get_features() implementation */ +static u64 vp_get_features(struct virtio_device *vdev) +{ + struct virtio_pci_device *vp_dev = to_vp_device(vdev); + + /* When someone needs more than 32 feature bits, we'll need to + * steal a bit to indicate that the rest are somewhere else. */ + return vp_legacy_get_features(&vp_dev->ldev); +} + +/* virtio config->finalize_features() implementation */ +static int vp_finalize_features(struct virtio_device *vdev) +{ + struct virtio_pci_device *vp_dev = to_vp_device(vdev); + + /* Give virtio_ring a chance to accept features. */ + vring_transport_features(vdev); + + /* Make sure we don't have any features > 32 bits! */ + BUG_ON((u32)vdev->features != vdev->features); + + /* We only support 32 feature bits. */ + vp_legacy_set_features(&vp_dev->ldev, vdev->features); + + return 0; +} + +/* virtio config->get() implementation */ +static void vp_get(struct virtio_device *vdev, unsigned int offset, + void *buf, unsigned int len) +{ + struct virtio_pci_device *vp_dev = to_vp_device(vdev); + void __iomem *ioaddr = vp_dev->ldev.ioaddr + + VIRTIO_PCI_CONFIG_OFF(vp_dev->msix_enabled) + + offset; + u8 *ptr = buf; + int i; + + for (i = 0; i < len; i++) + ptr[i] = ioread8(ioaddr + i); +} + +/* the config->set() implementation. it's symmetric to the config->get() + * implementation */ +static void vp_set(struct virtio_device *vdev, unsigned int offset, + const void *buf, unsigned int len) +{ + struct virtio_pci_device *vp_dev = to_vp_device(vdev); + void __iomem *ioaddr = vp_dev->ldev.ioaddr + + VIRTIO_PCI_CONFIG_OFF(vp_dev->msix_enabled) + + offset; + const u8 *ptr = buf; + int i; + + for (i = 0; i < len; i++) + iowrite8(ptr[i], ioaddr + i); +} + +/* config->{get,set}_status() implementations */ +static u8 vp_get_status(struct virtio_device *vdev) +{ + struct virtio_pci_device *vp_dev = to_vp_device(vdev); + return vp_legacy_get_status(&vp_dev->ldev); +} + +static void vp_set_status(struct virtio_device *vdev, u8 status) +{ + struct virtio_pci_device *vp_dev = to_vp_device(vdev); + /* We should never be setting status to 0. */ + BUG_ON(status == 0); + vp_legacy_set_status(&vp_dev->ldev, status); +} + +static void vp_reset(struct virtio_device *vdev) +{ + struct virtio_pci_device *vp_dev = to_vp_device(vdev); + /* 0 status means a reset. */ + vp_legacy_set_status(&vp_dev->ldev, 0); + /* Flush out the status write, and flush in device writes, + * including MSi-X interrupts, if any. */ + vp_legacy_get_status(&vp_dev->ldev); + /* Flush pending VQ/configuration callbacks. */ + vp_synchronize_vectors(vdev); +} + +static u16 vp_config_vector(struct virtio_pci_device *vp_dev, u16 vector) +{ + return vp_legacy_config_vector(&vp_dev->ldev, vector); +} + +static struct virtqueue *setup_vq(struct virtio_pci_device *vp_dev, + struct virtio_pci_vq_info *info, + unsigned int index, + void (*callback)(struct virtqueue *vq), + const char *name, + bool ctx, + u16 msix_vec) +{ + struct virtqueue *vq; + u16 num; + int err; + u64 q_pfn; + + /* Check if queue is either not available or already active. */ + num = vp_legacy_get_queue_size(&vp_dev->ldev, index); + if (!num || vp_legacy_get_queue_enable(&vp_dev->ldev, index)) + return ERR_PTR(-ENOENT); + + info->msix_vector = msix_vec; + + /* create the vring */ + vq = vring_create_virtqueue(index, num, + VIRTIO_PCI_VRING_ALIGN, &vp_dev->vdev, + true, false, ctx, + vp_notify, callback, name); + if (!vq) + return ERR_PTR(-ENOMEM); + + vq->num_max = num; + + q_pfn = virtqueue_get_desc_addr(vq) >> VIRTIO_PCI_QUEUE_ADDR_SHIFT; + if (q_pfn >> 32) { + dev_err(&vp_dev->pci_dev->dev, + "platform bug: legacy virtio-pci must not be used with RAM above 0x%llxGB\n", + 0x1ULL << (32 + PAGE_SHIFT - 30)); + err = -E2BIG; + goto out_del_vq; + } + + /* activate the queue */ + vp_legacy_set_queue_address(&vp_dev->ldev, index, q_pfn); + + vq->priv = (void __force *)vp_dev->ldev.ioaddr + VIRTIO_PCI_QUEUE_NOTIFY; + + if (msix_vec != VIRTIO_MSI_NO_VECTOR) { + msix_vec = vp_legacy_queue_vector(&vp_dev->ldev, index, msix_vec); + if (msix_vec == VIRTIO_MSI_NO_VECTOR) { + err = -EBUSY; + goto out_deactivate; + } + } + + return vq; + +out_deactivate: + vp_legacy_set_queue_address(&vp_dev->ldev, index, 0); +out_del_vq: + vring_del_virtqueue(vq); + return ERR_PTR(err); +} + +static void del_vq(struct virtio_pci_vq_info *info) +{ + struct virtqueue *vq = info->vq; + struct virtio_pci_device *vp_dev = to_vp_device(vq->vdev); + + if (vp_dev->msix_enabled) { + vp_legacy_queue_vector(&vp_dev->ldev, vq->index, + VIRTIO_MSI_NO_VECTOR); + /* Flush the write out to device */ + ioread8(vp_dev->ldev.ioaddr + VIRTIO_PCI_ISR); + } + + /* Select and deactivate the queue */ + vp_legacy_set_queue_address(&vp_dev->ldev, vq->index, 0); + + vring_del_virtqueue(vq); +} + +static const struct virtio_config_ops virtio_pci_config_ops = { + .get = vp_get, + .set = vp_set, + .get_status = vp_get_status, + .set_status = vp_set_status, + .reset = vp_reset, + .find_vqs = vp_find_vqs, + .del_vqs = vp_del_vqs, + .synchronize_cbs = vp_synchronize_vectors, + .get_features = vp_get_features, + .finalize_features = vp_finalize_features, + .bus_name = vp_bus_name, + .set_vq_affinity = vp_set_vq_affinity, + .get_vq_affinity = vp_get_vq_affinity, +}; + +/* the PCI probing function */ +int virtio_pci_legacy_probe(struct virtio_pci_device *vp_dev) +{ + struct virtio_pci_legacy_device *ldev = &vp_dev->ldev; + struct pci_dev *pci_dev = vp_dev->pci_dev; + int rc; + + ldev->pci_dev = pci_dev; + + rc = vp_legacy_probe(ldev); + if (rc) + return rc; + + vp_dev->isr = ldev->isr; + vp_dev->vdev.id = ldev->id; + + vp_dev->vdev.config = &virtio_pci_config_ops; + + vp_dev->config_vector = vp_config_vector; + vp_dev->setup_vq = setup_vq; + vp_dev->del_vq = del_vq; + vp_dev->is_legacy = true; + + return 0; +} + +void virtio_pci_legacy_remove(struct virtio_pci_device *vp_dev) +{ + struct virtio_pci_legacy_device *ldev = &vp_dev->ldev; + + vp_legacy_remove(ldev); +} diff --git a/drivers/virtio/virtio_pci_legacy_dev.c b/drivers/virtio/virtio_pci_legacy_dev.c new file mode 100644 index 000000000000..bbbf89c22880 --- /dev/null +++ b/drivers/virtio/virtio_pci_legacy_dev.c @@ -0,0 +1,222 @@ +// SPDX-License-Identifier: GPL-2.0-or-later + +#include "linux/virtio_pci.h" +#include <linux/virtio_pci_legacy.h> +#include <linux/module.h> +#include <linux/pci.h> + + +/* + * vp_legacy_probe: probe the legacy virtio pci device, note that the + * caller is required to enable PCI device before calling this function. + * @ldev: the legacy virtio-pci device + * + * Return 0 on succeed otherwise fail + */ +int vp_legacy_probe(struct virtio_pci_legacy_device *ldev) +{ + struct pci_dev *pci_dev = ldev->pci_dev; + int rc; + + /* We only own devices >= 0x1000 and <= 0x103f: leave the rest. */ + if (pci_dev->device < 0x1000 || pci_dev->device > 0x103f) + return -ENODEV; + + if (pci_dev->revision != VIRTIO_PCI_ABI_VERSION) + return -ENODEV; + + rc = dma_set_mask(&pci_dev->dev, DMA_BIT_MASK(64)); + if (rc) { + rc = dma_set_mask_and_coherent(&pci_dev->dev, DMA_BIT_MASK(32)); + } else { + /* + * The virtio ring base address is expressed as a 32-bit PFN, + * with a page size of 1 << VIRTIO_PCI_QUEUE_ADDR_SHIFT. + */ + dma_set_coherent_mask(&pci_dev->dev, + DMA_BIT_MASK(32 + VIRTIO_PCI_QUEUE_ADDR_SHIFT)); + } + + if (rc) + dev_warn(&pci_dev->dev, "Failed to enable 64-bit or 32-bit DMA. Trying to continue, but this might not work.\n"); + + rc = pci_request_region(pci_dev, 0, "virtio-pci-legacy"); + if (rc) + return rc; + + ldev->ioaddr = pci_iomap(pci_dev, 0, 0); + if (!ldev->ioaddr) { + rc = -EIO; + goto err_iomap; + } + + ldev->isr = ldev->ioaddr + VIRTIO_PCI_ISR; + + ldev->id.vendor = pci_dev->subsystem_vendor; + ldev->id.device = pci_dev->subsystem_device; + + return 0; +err_iomap: + pci_release_region(pci_dev, 0); + return rc; +} +EXPORT_SYMBOL_GPL(vp_legacy_probe); + +/* + * vp_legacy_probe: remove and cleanup the legacy virtio pci device + * @ldev: the legacy virtio-pci device + */ +void vp_legacy_remove(struct virtio_pci_legacy_device *ldev) +{ + struct pci_dev *pci_dev = ldev->pci_dev; + + pci_iounmap(pci_dev, ldev->ioaddr); + pci_release_region(pci_dev, 0); +} +EXPORT_SYMBOL_GPL(vp_legacy_remove); + +/* + * vp_legacy_get_features - get features from device + * @ldev: the legacy virtio-pci device + * + * Returns the features read from the device + */ +u64 vp_legacy_get_features(struct virtio_pci_legacy_device *ldev) +{ + + return ioread32(ldev->ioaddr + VIRTIO_PCI_HOST_FEATURES); +} +EXPORT_SYMBOL_GPL(vp_legacy_get_features); + +/* + * vp_legacy_get_driver_features - get driver features from device + * @ldev: the legacy virtio-pci device + * + * Returns the driver features read from the device + */ +u64 vp_legacy_get_driver_features(struct virtio_pci_legacy_device *ldev) +{ + return ioread32(ldev->ioaddr + VIRTIO_PCI_GUEST_FEATURES); +} +EXPORT_SYMBOL_GPL(vp_legacy_get_driver_features); + +/* + * vp_legacy_set_features - set features to device + * @ldev: the legacy virtio-pci device + * @features: the features set to device + */ +void vp_legacy_set_features(struct virtio_pci_legacy_device *ldev, + u32 features) +{ + iowrite32(features, ldev->ioaddr + VIRTIO_PCI_GUEST_FEATURES); +} +EXPORT_SYMBOL_GPL(vp_legacy_set_features); + +/* + * vp_legacy_get_status - get the device status + * @ldev: the legacy virtio-pci device + * + * Returns the status read from device + */ +u8 vp_legacy_get_status(struct virtio_pci_legacy_device *ldev) +{ + return ioread8(ldev->ioaddr + VIRTIO_PCI_STATUS); +} +EXPORT_SYMBOL_GPL(vp_legacy_get_status); + +/* + * vp_legacy_set_status - set status to device + * @ldev: the legacy virtio-pci device + * @status: the status set to device + */ +void vp_legacy_set_status(struct virtio_pci_legacy_device *ldev, + u8 status) +{ + iowrite8(status, ldev->ioaddr + VIRTIO_PCI_STATUS); +} +EXPORT_SYMBOL_GPL(vp_legacy_set_status); + +/* + * vp_legacy_queue_vector - set the MSIX vector for a specific virtqueue + * @ldev: the legacy virtio-pci device + * @index: queue index + * @vector: the queue vector + * + * Returns the queue vector read from the device + */ +u16 vp_legacy_queue_vector(struct virtio_pci_legacy_device *ldev, + u16 index, u16 vector) +{ + iowrite16(index, ldev->ioaddr + VIRTIO_PCI_QUEUE_SEL); + iowrite16(vector, ldev->ioaddr + VIRTIO_MSI_QUEUE_VECTOR); + /* Flush the write out to device */ + return ioread16(ldev->ioaddr + VIRTIO_MSI_QUEUE_VECTOR); +} +EXPORT_SYMBOL_GPL(vp_legacy_queue_vector); + +/* + * vp_legacy_config_vector - set the vector for config interrupt + * @ldev: the legacy virtio-pci device + * @vector: the config vector + * + * Returns the config vector read from the device + */ +u16 vp_legacy_config_vector(struct virtio_pci_legacy_device *ldev, + u16 vector) +{ + /* Setup the vector used for configuration events */ + iowrite16(vector, ldev->ioaddr + VIRTIO_MSI_CONFIG_VECTOR); + /* Verify we had enough resources to assign the vector */ + /* Will also flush the write out to device */ + return ioread16(ldev->ioaddr + VIRTIO_MSI_CONFIG_VECTOR); +} +EXPORT_SYMBOL_GPL(vp_legacy_config_vector); + +/* + * vp_legacy_set_queue_address - set the virtqueue address + * @ldev: the legacy virtio-pci device + * @index: the queue index + * @queue_pfn: pfn of the virtqueue + */ +void vp_legacy_set_queue_address(struct virtio_pci_legacy_device *ldev, + u16 index, u32 queue_pfn) +{ + iowrite16(index, ldev->ioaddr + VIRTIO_PCI_QUEUE_SEL); + iowrite32(queue_pfn, ldev->ioaddr + VIRTIO_PCI_QUEUE_PFN); +} +EXPORT_SYMBOL_GPL(vp_legacy_set_queue_address); + +/* + * vp_legacy_get_queue_enable - enable a virtqueue + * @ldev: the legacy virtio-pci device + * @index: the queue index + * + * Returns whether a virtqueue is enabled or not + */ +bool vp_legacy_get_queue_enable(struct virtio_pci_legacy_device *ldev, + u16 index) +{ + iowrite16(index, ldev->ioaddr + VIRTIO_PCI_QUEUE_SEL); + return ioread32(ldev->ioaddr + VIRTIO_PCI_QUEUE_PFN); +} +EXPORT_SYMBOL_GPL(vp_legacy_get_queue_enable); + +/* + * vp_legacy_get_queue_size - get size for a virtqueue + * @ldev: the legacy virtio-pci device + * @index: the queue index + * + * Returns the size of the virtqueue + */ +u16 vp_legacy_get_queue_size(struct virtio_pci_legacy_device *ldev, + u16 index) +{ + iowrite16(index, ldev->ioaddr + VIRTIO_PCI_QUEUE_SEL); + return ioread16(ldev->ioaddr + VIRTIO_PCI_QUEUE_NUM); +} +EXPORT_SYMBOL_GPL(vp_legacy_get_queue_size); + +MODULE_VERSION("0.1"); +MODULE_DESCRIPTION("Legacy Virtio PCI Device"); +MODULE_AUTHOR("Wu Zongyong <wuzongyong@linux.alibaba.com>"); +MODULE_LICENSE("GPL"); diff --git a/drivers/virtio/virtio_pci_modern.c b/drivers/virtio/virtio_pci_modern.c new file mode 100644 index 000000000000..dd0e65f71d41 --- /dev/null +++ b/drivers/virtio/virtio_pci_modern.c @@ -0,0 +1,1301 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * Virtio PCI driver - modern (virtio 1.0) device support + * + * This module allows virtio devices to be used over a virtual PCI device. + * This can be used with QEMU based VMMs like KVM or Xen. + * + * Copyright IBM Corp. 2007 + * Copyright Red Hat, Inc. 2014 + * + * Authors: + * Anthony Liguori <aliguori@us.ibm.com> + * Rusty Russell <rusty@rustcorp.com.au> + * Michael S. Tsirkin <mst@redhat.com> + */ + +#include <linux/delay.h> +#include <linux/virtio_pci_admin.h> +#define VIRTIO_PCI_NO_LEGACY +#define VIRTIO_RING_NO_LEGACY +#include "virtio_pci_common.h" + +#define VIRTIO_AVQ_SGS_MAX 4 + +static void vp_get_features(struct virtio_device *vdev, u64 *features) +{ + struct virtio_pci_device *vp_dev = to_vp_device(vdev); + + vp_modern_get_extended_features(&vp_dev->mdev, features); +} + +static int vp_avq_index(struct virtio_device *vdev, u16 *index, u16 *num) +{ + struct virtio_pci_device *vp_dev = to_vp_device(vdev); + + *num = 0; + if (!virtio_has_feature(vdev, VIRTIO_F_ADMIN_VQ)) + return 0; + + *num = vp_modern_avq_num(&vp_dev->mdev); + if (!(*num)) + return -EINVAL; + *index = vp_modern_avq_index(&vp_dev->mdev); + return 0; +} + +void vp_modern_avq_done(struct virtqueue *vq) +{ + struct virtio_pci_device *vp_dev = to_vp_device(vq->vdev); + struct virtio_pci_admin_vq *admin_vq = &vp_dev->admin_vq; + unsigned int status_size = sizeof(struct virtio_admin_cmd_status); + struct virtio_admin_cmd *cmd; + unsigned long flags; + unsigned int len; + + spin_lock_irqsave(&admin_vq->lock, flags); + do { + virtqueue_disable_cb(vq); + while ((cmd = virtqueue_get_buf(vq, &len))) { + /* If the number of bytes written by the device is less + * than the size of struct virtio_admin_cmd_status, the + * remaining status bytes will remain zero-initialized, + * since the buffer was zeroed during allocation. + * In this case, set the size of command_specific_result + * to 0. + */ + if (len < status_size) + cmd->result_sg_size = 0; + else + cmd->result_sg_size = len - status_size; + complete(&cmd->completion); + } + } while (!virtqueue_enable_cb(vq)); + spin_unlock_irqrestore(&admin_vq->lock, flags); +} + +static int virtqueue_exec_admin_cmd(struct virtio_pci_admin_vq *admin_vq, + u16 opcode, + struct scatterlist **sgs, + unsigned int out_num, + unsigned int in_num, + struct virtio_admin_cmd *cmd) +{ + struct virtqueue *vq; + unsigned long flags; + int ret; + + vq = admin_vq->info->vq; + if (!vq) + return -EIO; + + if (opcode != VIRTIO_ADMIN_CMD_LIST_QUERY && + opcode != VIRTIO_ADMIN_CMD_LIST_USE && + !((1ULL << opcode) & admin_vq->supported_cmds)) + return -EOPNOTSUPP; + + init_completion(&cmd->completion); + +again: + if (virtqueue_is_broken(vq)) + return -EIO; + + spin_lock_irqsave(&admin_vq->lock, flags); + ret = virtqueue_add_sgs(vq, sgs, out_num, in_num, cmd, GFP_KERNEL); + if (ret < 0) { + if (ret == -ENOSPC) { + spin_unlock_irqrestore(&admin_vq->lock, flags); + cpu_relax(); + goto again; + } + goto unlock_err; + } + if (!virtqueue_kick(vq)) + goto unlock_err; + spin_unlock_irqrestore(&admin_vq->lock, flags); + + wait_for_completion(&cmd->completion); + + return cmd->ret; + +unlock_err: + spin_unlock_irqrestore(&admin_vq->lock, flags); + return -EIO; +} + +int vp_modern_admin_cmd_exec(struct virtio_device *vdev, + struct virtio_admin_cmd *cmd) +{ + struct scatterlist *sgs[VIRTIO_AVQ_SGS_MAX], hdr, stat; + struct virtio_pci_device *vp_dev = to_vp_device(vdev); + struct virtio_admin_cmd_status *va_status; + unsigned int out_num = 0, in_num = 0; + struct virtio_admin_cmd_hdr *va_hdr; + u16 status; + int ret; + + if (!virtio_has_feature(vdev, VIRTIO_F_ADMIN_VQ)) + return -EOPNOTSUPP; + + va_status = kzalloc(sizeof(*va_status), GFP_KERNEL); + if (!va_status) + return -ENOMEM; + + va_hdr = kzalloc(sizeof(*va_hdr), GFP_KERNEL); + if (!va_hdr) { + ret = -ENOMEM; + goto err_alloc; + } + + va_hdr->opcode = cmd->opcode; + va_hdr->group_type = cmd->group_type; + va_hdr->group_member_id = cmd->group_member_id; + + /* Add header */ + sg_init_one(&hdr, va_hdr, sizeof(*va_hdr)); + sgs[out_num] = &hdr; + out_num++; + + if (cmd->data_sg) { + sgs[out_num] = cmd->data_sg; + out_num++; + } + + /* Add return status */ + sg_init_one(&stat, va_status, sizeof(*va_status)); + sgs[out_num + in_num] = &stat; + in_num++; + + if (cmd->result_sg) { + sgs[out_num + in_num] = cmd->result_sg; + in_num++; + } + + ret = virtqueue_exec_admin_cmd(&vp_dev->admin_vq, + le16_to_cpu(cmd->opcode), + sgs, out_num, in_num, cmd); + if (ret) { + dev_err(&vdev->dev, + "Failed to execute command on admin vq: %d\n.", ret); + goto err_cmd_exec; + } + + status = le16_to_cpu(va_status->status); + if (status != VIRTIO_ADMIN_STATUS_OK) { + dev_err(&vdev->dev, + "admin command error: status(%#x) qualifier(%#x)\n", + status, le16_to_cpu(va_status->status_qualifier)); + ret = -status; + } + +err_cmd_exec: + kfree(va_hdr); +err_alloc: + kfree(va_status); + return ret; +} + +static void virtio_pci_admin_cmd_list_init(struct virtio_device *virtio_dev) +{ + struct virtio_pci_device *vp_dev = to_vp_device(virtio_dev); + struct virtio_admin_cmd cmd = {}; + struct scatterlist result_sg; + struct scatterlist data_sg; + __le64 *data; + int ret; + + data = kzalloc(sizeof(*data), GFP_KERNEL); + if (!data) + return; + + sg_init_one(&result_sg, data, sizeof(*data)); + cmd.opcode = cpu_to_le16(VIRTIO_ADMIN_CMD_LIST_QUERY); + cmd.group_type = cpu_to_le16(VIRTIO_ADMIN_GROUP_TYPE_SRIOV); + cmd.result_sg = &result_sg; + + ret = vp_modern_admin_cmd_exec(virtio_dev, &cmd); + if (ret) + goto end; + + *data &= cpu_to_le64(VIRTIO_ADMIN_CMD_BITMAP); + sg_init_one(&data_sg, data, sizeof(*data)); + cmd.opcode = cpu_to_le16(VIRTIO_ADMIN_CMD_LIST_USE); + cmd.data_sg = &data_sg; + cmd.result_sg = NULL; + + ret = vp_modern_admin_cmd_exec(virtio_dev, &cmd); + if (ret) + goto end; + + vp_dev->admin_vq.supported_cmds = le64_to_cpu(*data); +end: + kfree(data); +} + +static void +virtio_pci_admin_cmd_dev_parts_objects_enable(struct virtio_device *virtio_dev) +{ + struct virtio_pci_device *vp_dev = to_vp_device(virtio_dev); + struct virtio_admin_cmd_cap_get_data *get_data; + struct virtio_admin_cmd_cap_set_data *set_data; + struct virtio_dev_parts_cap *result; + struct virtio_admin_cmd cmd = {}; + struct scatterlist result_sg; + struct scatterlist data_sg; + u8 resource_objects_limit; + u16 set_data_size; + int ret; + + get_data = kzalloc(sizeof(*get_data), GFP_KERNEL); + if (!get_data) + return; + + result = kzalloc(sizeof(*result), GFP_KERNEL); + if (!result) + goto end; + + get_data->id = cpu_to_le16(VIRTIO_DEV_PARTS_CAP); + sg_init_one(&data_sg, get_data, sizeof(*get_data)); + sg_init_one(&result_sg, result, sizeof(*result)); + cmd.opcode = cpu_to_le16(VIRTIO_ADMIN_CMD_DEVICE_CAP_GET); + cmd.group_type = cpu_to_le16(VIRTIO_ADMIN_GROUP_TYPE_SELF); + cmd.data_sg = &data_sg; + cmd.result_sg = &result_sg; + ret = vp_modern_admin_cmd_exec(virtio_dev, &cmd); + if (ret) + goto err_get; + + set_data_size = sizeof(*set_data) + sizeof(*result); + set_data = kzalloc(set_data_size, GFP_KERNEL); + if (!set_data) + goto err_get; + + set_data->id = cpu_to_le16(VIRTIO_DEV_PARTS_CAP); + + /* Set the limit to the minimum value between the GET and SET values + * supported by the device. Since the obj_id for VIRTIO_DEV_PARTS_CAP + * is a globally unique value per PF, there is no possibility of + * overlap between GET and SET operations. + */ + resource_objects_limit = min(result->get_parts_resource_objects_limit, + result->set_parts_resource_objects_limit); + result->get_parts_resource_objects_limit = resource_objects_limit; + result->set_parts_resource_objects_limit = resource_objects_limit; + memcpy(set_data->cap_specific_data, result, sizeof(*result)); + sg_init_one(&data_sg, set_data, set_data_size); + cmd.data_sg = &data_sg; + cmd.result_sg = NULL; + cmd.opcode = cpu_to_le16(VIRTIO_ADMIN_CMD_DRIVER_CAP_SET); + ret = vp_modern_admin_cmd_exec(virtio_dev, &cmd); + if (ret) + goto err_set; + + /* Allocate IDR to manage the dev caps objects */ + ida_init(&vp_dev->admin_vq.dev_parts_ida); + vp_dev->admin_vq.max_dev_parts_objects = resource_objects_limit; + +err_set: + kfree(set_data); +err_get: + kfree(result); +end: + kfree(get_data); +} + +static void virtio_pci_admin_cmd_cap_init(struct virtio_device *virtio_dev) +{ + struct virtio_pci_device *vp_dev = to_vp_device(virtio_dev); + struct virtio_admin_cmd_query_cap_id_result *data; + struct virtio_admin_cmd cmd = {}; + struct scatterlist result_sg; + int ret; + + data = kzalloc(sizeof(*data), GFP_KERNEL); + if (!data) + return; + + sg_init_one(&result_sg, data, sizeof(*data)); + cmd.opcode = cpu_to_le16(VIRTIO_ADMIN_CMD_CAP_ID_LIST_QUERY); + cmd.group_type = cpu_to_le16(VIRTIO_ADMIN_GROUP_TYPE_SELF); + cmd.result_sg = &result_sg; + + ret = vp_modern_admin_cmd_exec(virtio_dev, &cmd); + if (ret) + goto end; + + /* Max number of caps fits into a single u64 */ + BUILD_BUG_ON(sizeof(data->supported_caps) > sizeof(u64)); + + vp_dev->admin_vq.supported_caps = le64_to_cpu(data->supported_caps[0]); + + if (!(vp_dev->admin_vq.supported_caps & (1 << VIRTIO_DEV_PARTS_CAP))) + goto end; + + virtio_pci_admin_cmd_dev_parts_objects_enable(virtio_dev); +end: + kfree(data); +} + +static void vp_modern_avq_activate(struct virtio_device *vdev) +{ + if (!virtio_has_feature(vdev, VIRTIO_F_ADMIN_VQ)) + return; + + virtio_pci_admin_cmd_list_init(vdev); + virtio_pci_admin_cmd_cap_init(vdev); +} + +static void vp_modern_avq_cleanup(struct virtio_device *vdev) +{ + struct virtio_pci_device *vp_dev = to_vp_device(vdev); + struct virtio_admin_cmd *cmd; + struct virtqueue *vq; + + if (!virtio_has_feature(vdev, VIRTIO_F_ADMIN_VQ)) + return; + + vq = vp_dev->admin_vq.info->vq; + if (!vq) + return; + + while ((cmd = virtqueue_detach_unused_buf(vq))) { + cmd->ret = -EIO; + complete(&cmd->completion); + } +} + +static void vp_transport_features(struct virtio_device *vdev, u64 features) +{ + struct virtio_pci_device *vp_dev = to_vp_device(vdev); + struct pci_dev *pci_dev = vp_dev->pci_dev; + + if ((features & BIT_ULL(VIRTIO_F_SR_IOV)) && + pci_find_ext_capability(pci_dev, PCI_EXT_CAP_ID_SRIOV)) + __virtio_set_bit(vdev, VIRTIO_F_SR_IOV); + + if (features & BIT_ULL(VIRTIO_F_RING_RESET)) + __virtio_set_bit(vdev, VIRTIO_F_RING_RESET); + + if (features & BIT_ULL(VIRTIO_F_ADMIN_VQ)) + __virtio_set_bit(vdev, VIRTIO_F_ADMIN_VQ); +} + +static int __vp_check_common_size_one_feature(struct virtio_device *vdev, u32 fbit, + u32 offset, const char *fname) +{ + struct virtio_pci_device *vp_dev = to_vp_device(vdev); + + if (!__virtio_test_bit(vdev, fbit)) + return 0; + + if (likely(vp_dev->mdev.common_len >= offset)) + return 0; + + dev_err(&vdev->dev, + "virtio: common cfg size(%zu) does not match the feature %s\n", + vp_dev->mdev.common_len, fname); + + return -EINVAL; +} + +#define vp_check_common_size_one_feature(vdev, fbit, field) \ + __vp_check_common_size_one_feature(vdev, fbit, \ + offsetofend(struct virtio_pci_modern_common_cfg, field), #fbit) + +static int vp_check_common_size(struct virtio_device *vdev) +{ + if (vp_check_common_size_one_feature(vdev, VIRTIO_F_NOTIF_CONFIG_DATA, queue_notify_data)) + return -EINVAL; + + if (vp_check_common_size_one_feature(vdev, VIRTIO_F_RING_RESET, queue_reset)) + return -EINVAL; + + if (vp_check_common_size_one_feature(vdev, VIRTIO_F_ADMIN_VQ, admin_queue_num)) + return -EINVAL; + + return 0; +} + +/* virtio config->finalize_features() implementation */ +static int vp_finalize_features(struct virtio_device *vdev) +{ + struct virtio_pci_device *vp_dev = to_vp_device(vdev); + u64 features = vdev->features; + + /* Give virtio_ring a chance to accept features. */ + vring_transport_features(vdev); + + /* Give virtio_pci a chance to accept features. */ + vp_transport_features(vdev, features); + + if (!__virtio_test_bit(vdev, VIRTIO_F_VERSION_1)) { + dev_err(&vdev->dev, "virtio: device uses modern interface " + "but does not have VIRTIO_F_VERSION_1\n"); + return -EINVAL; + } + + if (vp_check_common_size(vdev)) + return -EINVAL; + + vp_modern_set_extended_features(&vp_dev->mdev, vdev->features_array); + + return 0; +} + +/* virtio config->get() implementation */ +static void vp_get(struct virtio_device *vdev, unsigned int offset, + void *buf, unsigned int len) +{ + struct virtio_pci_device *vp_dev = to_vp_device(vdev); + struct virtio_pci_modern_device *mdev = &vp_dev->mdev; + void __iomem *device = mdev->device; + u8 b; + __le16 w; + __le32 l; + + BUG_ON(offset + len > mdev->device_len); + + switch (len) { + case 1: + b = ioread8(device + offset); + memcpy(buf, &b, sizeof b); + break; + case 2: + w = cpu_to_le16(ioread16(device + offset)); + memcpy(buf, &w, sizeof w); + break; + case 4: + l = cpu_to_le32(ioread32(device + offset)); + memcpy(buf, &l, sizeof l); + break; + case 8: + l = cpu_to_le32(ioread32(device + offset)); + memcpy(buf, &l, sizeof l); + l = cpu_to_le32(ioread32(device + offset + sizeof l)); + memcpy(buf + sizeof l, &l, sizeof l); + break; + default: + BUG(); + } +} + +/* the config->set() implementation. it's symmetric to the config->get() + * implementation */ +static void vp_set(struct virtio_device *vdev, unsigned int offset, + const void *buf, unsigned int len) +{ + struct virtio_pci_device *vp_dev = to_vp_device(vdev); + struct virtio_pci_modern_device *mdev = &vp_dev->mdev; + void __iomem *device = mdev->device; + u8 b; + __le16 w; + __le32 l; + + BUG_ON(offset + len > mdev->device_len); + + switch (len) { + case 1: + memcpy(&b, buf, sizeof b); + iowrite8(b, device + offset); + break; + case 2: + memcpy(&w, buf, sizeof w); + iowrite16(le16_to_cpu(w), device + offset); + break; + case 4: + memcpy(&l, buf, sizeof l); + iowrite32(le32_to_cpu(l), device + offset); + break; + case 8: + memcpy(&l, buf, sizeof l); + iowrite32(le32_to_cpu(l), device + offset); + memcpy(&l, buf + sizeof l, sizeof l); + iowrite32(le32_to_cpu(l), device + offset + sizeof l); + break; + default: + BUG(); + } +} + +static u32 vp_generation(struct virtio_device *vdev) +{ + struct virtio_pci_device *vp_dev = to_vp_device(vdev); + + return vp_modern_generation(&vp_dev->mdev); +} + +/* config->{get,set}_status() implementations */ +static u8 vp_get_status(struct virtio_device *vdev) +{ + struct virtio_pci_device *vp_dev = to_vp_device(vdev); + + return vp_modern_get_status(&vp_dev->mdev); +} + +static void vp_set_status(struct virtio_device *vdev, u8 status) +{ + struct virtio_pci_device *vp_dev = to_vp_device(vdev); + + /* We should never be setting status to 0. */ + BUG_ON(status == 0); + vp_modern_set_status(&vp_dev->mdev, status); + if (status & VIRTIO_CONFIG_S_DRIVER_OK) + vp_modern_avq_activate(vdev); +} + +static void vp_reset(struct virtio_device *vdev) +{ + struct virtio_pci_device *vp_dev = to_vp_device(vdev); + struct virtio_pci_modern_device *mdev = &vp_dev->mdev; + + /* 0 status means a reset. */ + vp_modern_set_status(mdev, 0); + /* After writing 0 to device_status, the driver MUST wait for a read of + * device_status to return 0 before reinitializing the device. + * This will flush out the status write, and flush in device writes, + * including MSI-X interrupts, if any. + */ + while (vp_modern_get_status(mdev)) + msleep(1); + + vp_modern_avq_cleanup(vdev); + + /* Flush pending VQ/configuration callbacks. */ + vp_synchronize_vectors(vdev); +} + +static int vp_active_vq(struct virtqueue *vq, u16 msix_vec) +{ + struct virtio_pci_device *vp_dev = to_vp_device(vq->vdev); + struct virtio_pci_modern_device *mdev = &vp_dev->mdev; + unsigned long index; + + index = vq->index; + + /* activate the queue */ + vp_modern_set_queue_size(mdev, index, virtqueue_get_vring_size(vq)); + vp_modern_queue_address(mdev, index, virtqueue_get_desc_addr(vq), + virtqueue_get_avail_addr(vq), + virtqueue_get_used_addr(vq)); + + if (msix_vec != VIRTIO_MSI_NO_VECTOR) { + msix_vec = vp_modern_queue_vector(mdev, index, msix_vec); + if (msix_vec == VIRTIO_MSI_NO_VECTOR) + return -EBUSY; + } + + return 0; +} + +static int vp_modern_disable_vq_and_reset(struct virtqueue *vq) +{ + struct virtio_pci_device *vp_dev = to_vp_device(vq->vdev); + struct virtio_pci_modern_device *mdev = &vp_dev->mdev; + struct virtio_pci_vq_info *info; + unsigned long flags; + + if (!virtio_has_feature(vq->vdev, VIRTIO_F_RING_RESET)) + return -ENOENT; + + vp_modern_set_queue_reset(mdev, vq->index); + + info = vp_dev->vqs[vq->index]; + + /* delete vq from irq handler */ + spin_lock_irqsave(&vp_dev->lock, flags); + list_del(&info->node); + spin_unlock_irqrestore(&vp_dev->lock, flags); + + INIT_LIST_HEAD(&info->node); + +#ifdef CONFIG_VIRTIO_HARDEN_NOTIFICATION + __virtqueue_break(vq); +#endif + + /* For the case where vq has an exclusive irq, call synchronize_irq() to + * wait for completion. + * + * note: We can't use disable_irq() since it conflicts with the affinity + * managed IRQ that is used by some drivers. + */ + if (vp_dev->per_vq_vectors && info->msix_vector != VIRTIO_MSI_NO_VECTOR) + synchronize_irq(pci_irq_vector(vp_dev->pci_dev, info->msix_vector)); + + vq->reset = true; + + return 0; +} + +static int vp_modern_enable_vq_after_reset(struct virtqueue *vq) +{ + struct virtio_pci_device *vp_dev = to_vp_device(vq->vdev); + struct virtio_pci_modern_device *mdev = &vp_dev->mdev; + struct virtio_pci_vq_info *info; + unsigned long flags, index; + int err; + + if (!vq->reset) + return -EBUSY; + + index = vq->index; + info = vp_dev->vqs[index]; + + if (vp_modern_get_queue_reset(mdev, index)) + return -EBUSY; + + if (vp_modern_get_queue_enable(mdev, index)) + return -EBUSY; + + err = vp_active_vq(vq, info->msix_vector); + if (err) + return err; + + if (vq->callback) { + spin_lock_irqsave(&vp_dev->lock, flags); + list_add(&info->node, &vp_dev->virtqueues); + spin_unlock_irqrestore(&vp_dev->lock, flags); + } else { + INIT_LIST_HEAD(&info->node); + } + +#ifdef CONFIG_VIRTIO_HARDEN_NOTIFICATION + __virtqueue_unbreak(vq); +#endif + + vp_modern_set_queue_enable(&vp_dev->mdev, index, true); + vq->reset = false; + + return 0; +} + +static u16 vp_config_vector(struct virtio_pci_device *vp_dev, u16 vector) +{ + return vp_modern_config_vector(&vp_dev->mdev, vector); +} + +static bool vp_notify_with_data(struct virtqueue *vq) +{ + u32 data = vring_notification_data(vq); + + iowrite32(data, (void __iomem *)vq->priv); + + return true; +} + +static struct virtqueue *setup_vq(struct virtio_pci_device *vp_dev, + struct virtio_pci_vq_info *info, + unsigned int index, + void (*callback)(struct virtqueue *vq), + const char *name, + bool ctx, + u16 msix_vec) +{ + + struct virtio_pci_modern_device *mdev = &vp_dev->mdev; + bool (*notify)(struct virtqueue *vq); + struct virtqueue *vq; + bool is_avq; + u16 num; + int err; + + if (__virtio_test_bit(&vp_dev->vdev, VIRTIO_F_NOTIFICATION_DATA)) + notify = vp_notify_with_data; + else + notify = vp_notify; + + is_avq = vp_is_avq(&vp_dev->vdev, index); + if (index >= vp_modern_get_num_queues(mdev) && !is_avq) + return ERR_PTR(-EINVAL); + + num = vp_modern_get_queue_size(mdev, index); + /* Check if queue is either not available or already active. */ + if (!num || vp_modern_get_queue_enable(mdev, index)) + return ERR_PTR(-ENOENT); + + info->msix_vector = msix_vec; + + /* create the vring */ + vq = vring_create_virtqueue(index, num, + SMP_CACHE_BYTES, &vp_dev->vdev, + true, true, ctx, + notify, callback, name); + if (!vq) + return ERR_PTR(-ENOMEM); + + vq->num_max = num; + + err = vp_active_vq(vq, msix_vec); + if (err) + goto err; + + vq->priv = (void __force *)vp_modern_map_vq_notify(mdev, index, NULL); + if (!vq->priv) { + err = -ENOMEM; + goto err; + } + + return vq; + +err: + vring_del_virtqueue(vq); + return ERR_PTR(err); +} + +static int vp_modern_find_vqs(struct virtio_device *vdev, unsigned int nvqs, + struct virtqueue *vqs[], + struct virtqueue_info vqs_info[], + struct irq_affinity *desc) +{ + struct virtio_pci_device *vp_dev = to_vp_device(vdev); + struct virtqueue *vq; + int rc = vp_find_vqs(vdev, nvqs, vqs, vqs_info, desc); + + if (rc) + return rc; + + /* Select and activate all queues. Has to be done last: once we do + * this, there's no way to go back except reset. + */ + list_for_each_entry(vq, &vdev->vqs, list) + vp_modern_set_queue_enable(&vp_dev->mdev, vq->index, true); + + return 0; +} + +static void del_vq(struct virtio_pci_vq_info *info) +{ + struct virtqueue *vq = info->vq; + struct virtio_pci_device *vp_dev = to_vp_device(vq->vdev); + struct virtio_pci_modern_device *mdev = &vp_dev->mdev; + + if (vp_dev->msix_enabled) + vp_modern_queue_vector(mdev, vq->index, + VIRTIO_MSI_NO_VECTOR); + + if (!mdev->notify_base) + pci_iounmap(mdev->pci_dev, (void __force __iomem *)vq->priv); + + vring_del_virtqueue(vq); +} + +static int virtio_pci_find_shm_cap(struct pci_dev *dev, u8 required_id, + u8 *bar, u64 *offset, u64 *len) +{ + int pos; + + for (pos = pci_find_capability(dev, PCI_CAP_ID_VNDR); pos > 0; + pos = pci_find_next_capability(dev, pos, PCI_CAP_ID_VNDR)) { + u8 type, cap_len, id, res_bar; + u32 tmp32; + u64 res_offset, res_length; + + pci_read_config_byte(dev, pos + offsetof(struct virtio_pci_cap, + cfg_type), &type); + if (type != VIRTIO_PCI_CAP_SHARED_MEMORY_CFG) + continue; + + pci_read_config_byte(dev, pos + offsetof(struct virtio_pci_cap, + cap_len), &cap_len); + if (cap_len != sizeof(struct virtio_pci_cap64)) { + dev_err(&dev->dev, "%s: shm cap with bad size offset:" + " %d size: %d\n", __func__, pos, cap_len); + continue; + } + + pci_read_config_byte(dev, pos + offsetof(struct virtio_pci_cap, + id), &id); + if (id != required_id) + continue; + + pci_read_config_byte(dev, pos + offsetof(struct virtio_pci_cap, + bar), &res_bar); + if (res_bar >= PCI_STD_NUM_BARS) + continue; + + /* Type and ID match, and the BAR value isn't reserved. + * Looks good. + */ + + /* Read the lower 32bit of length and offset */ + pci_read_config_dword(dev, pos + offsetof(struct virtio_pci_cap, + offset), &tmp32); + res_offset = tmp32; + pci_read_config_dword(dev, pos + offsetof(struct virtio_pci_cap, + length), &tmp32); + res_length = tmp32; + + /* and now the top half */ + pci_read_config_dword(dev, + pos + offsetof(struct virtio_pci_cap64, + offset_hi), &tmp32); + res_offset |= ((u64)tmp32) << 32; + pci_read_config_dword(dev, + pos + offsetof(struct virtio_pci_cap64, + length_hi), &tmp32); + res_length |= ((u64)tmp32) << 32; + + *bar = res_bar; + *offset = res_offset; + *len = res_length; + + return pos; + } + return 0; +} + +static bool vp_get_shm_region(struct virtio_device *vdev, + struct virtio_shm_region *region, u8 id) +{ + struct virtio_pci_device *vp_dev = to_vp_device(vdev); + struct pci_dev *pci_dev = vp_dev->pci_dev; + u8 bar; + u64 offset, len; + phys_addr_t phys_addr; + size_t bar_len; + + if (!virtio_pci_find_shm_cap(pci_dev, id, &bar, &offset, &len)) + return false; + + phys_addr = pci_resource_start(pci_dev, bar); + bar_len = pci_resource_len(pci_dev, bar); + + if ((offset + len) < offset) { + dev_err(&pci_dev->dev, "%s: cap offset+len overflow detected\n", + __func__); + return false; + } + + if (offset + len > bar_len) { + dev_err(&pci_dev->dev, "%s: bar shorter than cap offset+len\n", + __func__); + return false; + } + + region->len = len; + region->addr = (u64) phys_addr + offset; + + return true; +} + +/* + * virtio_pci_admin_has_dev_parts - Checks whether the device parts + * functionality is supported + * @pdev: VF pci_dev + * + * Returns true on success. + */ +bool virtio_pci_admin_has_dev_parts(struct pci_dev *pdev) +{ + struct virtio_device *virtio_dev = virtio_pci_vf_get_pf_dev(pdev); + struct virtio_pci_device *vp_dev; + + if (!virtio_dev) + return false; + + if (!virtio_has_feature(virtio_dev, VIRTIO_F_ADMIN_VQ)) + return false; + + vp_dev = to_vp_device(virtio_dev); + + if (!((vp_dev->admin_vq.supported_cmds & VIRTIO_DEV_PARTS_ADMIN_CMD_BITMAP) == + VIRTIO_DEV_PARTS_ADMIN_CMD_BITMAP)) + return false; + + return vp_dev->admin_vq.max_dev_parts_objects; +} +EXPORT_SYMBOL_GPL(virtio_pci_admin_has_dev_parts); + +/* + * virtio_pci_admin_mode_set - Sets the mode of a member device + * @pdev: VF pci_dev + * @flags: device mode's flags + * + * Note: caller must serialize access for the given device. + * Returns 0 on success, or negative on failure. + */ +int virtio_pci_admin_mode_set(struct pci_dev *pdev, u8 flags) +{ + struct virtio_device *virtio_dev = virtio_pci_vf_get_pf_dev(pdev); + struct virtio_admin_cmd_dev_mode_set_data *data; + struct virtio_admin_cmd cmd = {}; + struct scatterlist data_sg; + int vf_id; + int ret; + + if (!virtio_dev) + return -ENODEV; + + vf_id = pci_iov_vf_id(pdev); + if (vf_id < 0) + return vf_id; + + data = kzalloc(sizeof(*data), GFP_KERNEL); + if (!data) + return -ENOMEM; + + data->flags = flags; + sg_init_one(&data_sg, data, sizeof(*data)); + cmd.opcode = cpu_to_le16(VIRTIO_ADMIN_CMD_DEV_MODE_SET); + cmd.group_type = cpu_to_le16(VIRTIO_ADMIN_GROUP_TYPE_SRIOV); + cmd.group_member_id = cpu_to_le64(vf_id + 1); + cmd.data_sg = &data_sg; + ret = vp_modern_admin_cmd_exec(virtio_dev, &cmd); + + kfree(data); + return ret; +} +EXPORT_SYMBOL_GPL(virtio_pci_admin_mode_set); + +/* + * virtio_pci_admin_obj_create - Creates an object for a given type and operation, + * following the max objects that can be created for that request. + * @pdev: VF pci_dev + * @obj_type: Object type + * @operation_type: Operation type + * @obj_id: Output unique object id + * + * Note: caller must serialize access for the given device. + * Returns 0 on success, or negative on failure. + */ +int virtio_pci_admin_obj_create(struct pci_dev *pdev, u16 obj_type, u8 operation_type, + u32 *obj_id) +{ + struct virtio_device *virtio_dev = virtio_pci_vf_get_pf_dev(pdev); + u16 data_size = sizeof(struct virtio_admin_cmd_resource_obj_create_data); + struct virtio_admin_cmd_resource_obj_create_data *obj_create_data; + struct virtio_resource_obj_dev_parts obj_dev_parts = {}; + struct virtio_pci_admin_vq *avq; + struct virtio_admin_cmd cmd = {}; + struct scatterlist data_sg; + void *data; + int id = -1; + int vf_id; + int ret; + + if (!virtio_dev) + return -ENODEV; + + vf_id = pci_iov_vf_id(pdev); + if (vf_id < 0) + return vf_id; + + if (obj_type != VIRTIO_RESOURCE_OBJ_DEV_PARTS) + return -EOPNOTSUPP; + + if (operation_type != VIRTIO_RESOURCE_OBJ_DEV_PARTS_TYPE_GET && + operation_type != VIRTIO_RESOURCE_OBJ_DEV_PARTS_TYPE_SET) + return -EINVAL; + + avq = &to_vp_device(virtio_dev)->admin_vq; + if (!avq->max_dev_parts_objects) + return -EOPNOTSUPP; + + id = ida_alloc_range(&avq->dev_parts_ida, 0, + avq->max_dev_parts_objects - 1, GFP_KERNEL); + if (id < 0) + return id; + + *obj_id = id; + data_size += sizeof(obj_dev_parts); + data = kzalloc(data_size, GFP_KERNEL); + if (!data) { + ret = -ENOMEM; + goto end; + } + + obj_create_data = data; + obj_create_data->hdr.type = cpu_to_le16(obj_type); + obj_create_data->hdr.id = cpu_to_le32(*obj_id); + obj_dev_parts.type = operation_type; + memcpy(obj_create_data->resource_obj_specific_data, &obj_dev_parts, + sizeof(obj_dev_parts)); + sg_init_one(&data_sg, data, data_size); + cmd.opcode = cpu_to_le16(VIRTIO_ADMIN_CMD_RESOURCE_OBJ_CREATE); + cmd.group_type = cpu_to_le16(VIRTIO_ADMIN_GROUP_TYPE_SRIOV); + cmd.group_member_id = cpu_to_le64(vf_id + 1); + cmd.data_sg = &data_sg; + ret = vp_modern_admin_cmd_exec(virtio_dev, &cmd); + + kfree(data); +end: + if (ret) + ida_free(&avq->dev_parts_ida, id); + + return ret; +} +EXPORT_SYMBOL_GPL(virtio_pci_admin_obj_create); + +/* + * virtio_pci_admin_obj_destroy - Destroys an object of a given type and id + * @pdev: VF pci_dev + * @obj_type: Object type + * @id: Object id + * + * Note: caller must serialize access for the given device. + * Returns 0 on success, or negative on failure. + */ +int virtio_pci_admin_obj_destroy(struct pci_dev *pdev, u16 obj_type, u32 id) +{ + struct virtio_device *virtio_dev = virtio_pci_vf_get_pf_dev(pdev); + struct virtio_admin_cmd_resource_obj_cmd_hdr *data; + struct virtio_pci_device *vp_dev; + struct virtio_admin_cmd cmd = {}; + struct scatterlist data_sg; + int vf_id; + int ret; + + if (!virtio_dev) + return -ENODEV; + + vf_id = pci_iov_vf_id(pdev); + if (vf_id < 0) + return vf_id; + + if (obj_type != VIRTIO_RESOURCE_OBJ_DEV_PARTS) + return -EINVAL; + + data = kzalloc(sizeof(*data), GFP_KERNEL); + if (!data) + return -ENOMEM; + + data->type = cpu_to_le16(obj_type); + data->id = cpu_to_le32(id); + sg_init_one(&data_sg, data, sizeof(*data)); + cmd.opcode = cpu_to_le16(VIRTIO_ADMIN_CMD_RESOURCE_OBJ_DESTROY); + cmd.group_type = cpu_to_le16(VIRTIO_ADMIN_GROUP_TYPE_SRIOV); + cmd.group_member_id = cpu_to_le64(vf_id + 1); + cmd.data_sg = &data_sg; + ret = vp_modern_admin_cmd_exec(virtio_dev, &cmd); + if (!ret) { + vp_dev = to_vp_device(virtio_dev); + ida_free(&vp_dev->admin_vq.dev_parts_ida, id); + } + + kfree(data); + return ret; +} +EXPORT_SYMBOL_GPL(virtio_pci_admin_obj_destroy); + +/* + * virtio_pci_admin_dev_parts_metadata_get - Gets the metadata of the device parts + * identified by the below attributes. + * @pdev: VF pci_dev + * @obj_type: Object type + * @id: Object id + * @metadata_type: Metadata type + * @out: Upon success holds the output for 'metadata type size' + * + * Note: caller must serialize access for the given device. + * Returns 0 on success, or negative on failure. + */ +int virtio_pci_admin_dev_parts_metadata_get(struct pci_dev *pdev, u16 obj_type, + u32 id, u8 metadata_type, u32 *out) +{ + struct virtio_device *virtio_dev = virtio_pci_vf_get_pf_dev(pdev); + struct virtio_admin_cmd_dev_parts_metadata_result *result; + struct virtio_admin_cmd_dev_parts_metadata_data *data; + struct scatterlist data_sg, result_sg; + struct virtio_admin_cmd cmd = {}; + int vf_id; + int ret; + + if (!virtio_dev) + return -ENODEV; + + if (metadata_type != VIRTIO_ADMIN_CMD_DEV_PARTS_METADATA_TYPE_SIZE) + return -EOPNOTSUPP; + + vf_id = pci_iov_vf_id(pdev); + if (vf_id < 0) + return vf_id; + + data = kzalloc(sizeof(*data), GFP_KERNEL); + if (!data) + return -ENOMEM; + + result = kzalloc(sizeof(*result), GFP_KERNEL); + if (!result) { + ret = -ENOMEM; + goto end; + } + + data->hdr.type = cpu_to_le16(obj_type); + data->hdr.id = cpu_to_le32(id); + data->type = metadata_type; + sg_init_one(&data_sg, data, sizeof(*data)); + sg_init_one(&result_sg, result, sizeof(*result)); + cmd.opcode = cpu_to_le16(VIRTIO_ADMIN_CMD_DEV_PARTS_METADATA_GET); + cmd.group_type = cpu_to_le16(VIRTIO_ADMIN_GROUP_TYPE_SRIOV); + cmd.group_member_id = cpu_to_le64(vf_id + 1); + cmd.data_sg = &data_sg; + cmd.result_sg = &result_sg; + ret = vp_modern_admin_cmd_exec(virtio_dev, &cmd); + if (!ret) + *out = le32_to_cpu(result->parts_size.size); + + kfree(result); +end: + kfree(data); + return ret; +} +EXPORT_SYMBOL_GPL(virtio_pci_admin_dev_parts_metadata_get); + +/* + * virtio_pci_admin_dev_parts_get - Gets the device parts identified by the below attributes. + * @pdev: VF pci_dev + * @obj_type: Object type + * @id: Object id + * @get_type: Get type + * @res_sg: Upon success holds the output result data + * @res_size: Upon success holds the output result size + * + * Note: caller must serialize access for the given device. + * Returns 0 on success, or negative on failure. + */ +int virtio_pci_admin_dev_parts_get(struct pci_dev *pdev, u16 obj_type, u32 id, + u8 get_type, struct scatterlist *res_sg, + u32 *res_size) +{ + struct virtio_device *virtio_dev = virtio_pci_vf_get_pf_dev(pdev); + struct virtio_admin_cmd_dev_parts_get_data *data; + struct scatterlist data_sg; + struct virtio_admin_cmd cmd = {}; + int vf_id; + int ret; + + if (!virtio_dev) + return -ENODEV; + + if (get_type != VIRTIO_ADMIN_CMD_DEV_PARTS_GET_TYPE_ALL) + return -EOPNOTSUPP; + + vf_id = pci_iov_vf_id(pdev); + if (vf_id < 0) + return vf_id; + + data = kzalloc(sizeof(*data), GFP_KERNEL); + if (!data) + return -ENOMEM; + + data->hdr.type = cpu_to_le16(obj_type); + data->hdr.id = cpu_to_le32(id); + data->type = get_type; + sg_init_one(&data_sg, data, sizeof(*data)); + cmd.opcode = cpu_to_le16(VIRTIO_ADMIN_CMD_DEV_PARTS_GET); + cmd.group_type = cpu_to_le16(VIRTIO_ADMIN_GROUP_TYPE_SRIOV); + cmd.group_member_id = cpu_to_le64(vf_id + 1); + cmd.data_sg = &data_sg; + cmd.result_sg = res_sg; + ret = vp_modern_admin_cmd_exec(virtio_dev, &cmd); + if (!ret) + *res_size = cmd.result_sg_size; + + kfree(data); + return ret; +} +EXPORT_SYMBOL_GPL(virtio_pci_admin_dev_parts_get); + +/* + * virtio_pci_admin_dev_parts_set - Sets the device parts identified by the below attributes. + * @pdev: VF pci_dev + * @data_sg: The device parts data, its layout follows struct virtio_admin_cmd_dev_parts_set_data + * + * Note: caller must serialize access for the given device. + * Returns 0 on success, or negative on failure. + */ +int virtio_pci_admin_dev_parts_set(struct pci_dev *pdev, struct scatterlist *data_sg) +{ + struct virtio_device *virtio_dev = virtio_pci_vf_get_pf_dev(pdev); + struct virtio_admin_cmd cmd = {}; + int vf_id; + + if (!virtio_dev) + return -ENODEV; + + vf_id = pci_iov_vf_id(pdev); + if (vf_id < 0) + return vf_id; + + cmd.opcode = cpu_to_le16(VIRTIO_ADMIN_CMD_DEV_PARTS_SET); + cmd.group_type = cpu_to_le16(VIRTIO_ADMIN_GROUP_TYPE_SRIOV); + cmd.group_member_id = cpu_to_le64(vf_id + 1); + cmd.data_sg = data_sg; + return vp_modern_admin_cmd_exec(virtio_dev, &cmd); +} +EXPORT_SYMBOL_GPL(virtio_pci_admin_dev_parts_set); + +static const struct virtio_config_ops virtio_pci_config_nodev_ops = { + .get = NULL, + .set = NULL, + .generation = vp_generation, + .get_status = vp_get_status, + .set_status = vp_set_status, + .reset = vp_reset, + .find_vqs = vp_modern_find_vqs, + .del_vqs = vp_del_vqs, + .synchronize_cbs = vp_synchronize_vectors, + .get_extended_features = vp_get_features, + .finalize_features = vp_finalize_features, + .bus_name = vp_bus_name, + .set_vq_affinity = vp_set_vq_affinity, + .get_vq_affinity = vp_get_vq_affinity, + .get_shm_region = vp_get_shm_region, + .disable_vq_and_reset = vp_modern_disable_vq_and_reset, + .enable_vq_after_reset = vp_modern_enable_vq_after_reset, +}; + +static const struct virtio_config_ops virtio_pci_config_ops = { + .get = vp_get, + .set = vp_set, + .generation = vp_generation, + .get_status = vp_get_status, + .set_status = vp_set_status, + .reset = vp_reset, + .find_vqs = vp_modern_find_vqs, + .del_vqs = vp_del_vqs, + .synchronize_cbs = vp_synchronize_vectors, + .get_extended_features = vp_get_features, + .finalize_features = vp_finalize_features, + .bus_name = vp_bus_name, + .set_vq_affinity = vp_set_vq_affinity, + .get_vq_affinity = vp_get_vq_affinity, + .get_shm_region = vp_get_shm_region, + .disable_vq_and_reset = vp_modern_disable_vq_and_reset, + .enable_vq_after_reset = vp_modern_enable_vq_after_reset, +}; + +/* the PCI probing function */ +int virtio_pci_modern_probe(struct virtio_pci_device *vp_dev) +{ + struct virtio_pci_modern_device *mdev = &vp_dev->mdev; + struct pci_dev *pci_dev = vp_dev->pci_dev; + int err; + + mdev->pci_dev = pci_dev; + + err = vp_modern_probe(mdev); + if (err) + return err; + + if (mdev->device) + vp_dev->vdev.config = &virtio_pci_config_ops; + else + vp_dev->vdev.config = &virtio_pci_config_nodev_ops; + + vp_dev->config_vector = vp_config_vector; + vp_dev->setup_vq = setup_vq; + vp_dev->del_vq = del_vq; + vp_dev->avq_index = vp_avq_index; + vp_dev->isr = mdev->isr; + vp_dev->vdev.id = mdev->id; + + spin_lock_init(&vp_dev->admin_vq.lock); + return 0; +} + +void virtio_pci_modern_remove(struct virtio_pci_device *vp_dev) +{ + struct virtio_pci_modern_device *mdev = &vp_dev->mdev; + + vp_modern_remove(mdev); +} diff --git a/drivers/virtio/virtio_pci_modern_dev.c b/drivers/virtio/virtio_pci_modern_dev.c new file mode 100644 index 000000000000..413a8c353463 --- /dev/null +++ b/drivers/virtio/virtio_pci_modern_dev.c @@ -0,0 +1,758 @@ +// SPDX-License-Identifier: GPL-2.0-or-later + +#include <linux/virtio_pci_modern.h> +#include <linux/module.h> +#include <linux/pci.h> +#include <linux/delay.h> + +/* + * vp_modern_map_capability - map a part of virtio pci capability + * @mdev: the modern virtio-pci device + * @off: offset of the capability + * @minlen: minimal length of the capability + * @align: align requirement + * @start: start from the capability + * @size: map size + * @len: the length that is actually mapped + * @pa: physical address of the capability + * + * Returns the io address of for the part of the capability + */ +static void __iomem * +vp_modern_map_capability(struct virtio_pci_modern_device *mdev, int off, + size_t minlen, u32 align, u32 start, u32 size, + size_t *len, resource_size_t *pa) +{ + struct pci_dev *dev = mdev->pci_dev; + u8 bar; + u32 offset, length; + void __iomem *p; + + pci_read_config_byte(dev, off + offsetof(struct virtio_pci_cap, + bar), + &bar); + pci_read_config_dword(dev, off + offsetof(struct virtio_pci_cap, offset), + &offset); + pci_read_config_dword(dev, off + offsetof(struct virtio_pci_cap, length), + &length); + + /* Check if the BAR may have changed since we requested the region. */ + if (bar >= PCI_STD_NUM_BARS || !(mdev->modern_bars & (1 << bar))) { + dev_err(&dev->dev, + "virtio_pci: bar unexpectedly changed to %u\n", bar); + return NULL; + } + + if (length <= start) { + dev_err(&dev->dev, + "virtio_pci: bad capability len %u (>%u expected)\n", + length, start); + return NULL; + } + + if (length - start < minlen) { + dev_err(&dev->dev, + "virtio_pci: bad capability len %u (>=%zu expected)\n", + length, minlen); + return NULL; + } + + length -= start; + + if (start + offset < offset) { + dev_err(&dev->dev, + "virtio_pci: map wrap-around %u+%u\n", + start, offset); + return NULL; + } + + offset += start; + + if (offset & (align - 1)) { + dev_err(&dev->dev, + "virtio_pci: offset %u not aligned to %u\n", + offset, align); + return NULL; + } + + if (length > size) + length = size; + + if (len) + *len = length; + + if (minlen + offset < minlen || + minlen + offset > pci_resource_len(dev, bar)) { + dev_err(&dev->dev, + "virtio_pci: map virtio %zu@%u " + "out of range on bar %i length %lu\n", + minlen, offset, + bar, (unsigned long)pci_resource_len(dev, bar)); + return NULL; + } + + p = pci_iomap_range(dev, bar, offset, length); + if (!p) + dev_err(&dev->dev, + "virtio_pci: unable to map virtio %u@%u on bar %i\n", + length, offset, bar); + else if (pa) + *pa = pci_resource_start(dev, bar) + offset; + + return p; +} + +/** + * virtio_pci_find_capability - walk capabilities to find device info. + * @dev: the pci device + * @cfg_type: the VIRTIO_PCI_CAP_* value we seek + * @ioresource_types: IORESOURCE_MEM and/or IORESOURCE_IO. + * @bars: the bitmask of BARs + * + * Returns offset of the capability, or 0. + */ +static inline int virtio_pci_find_capability(struct pci_dev *dev, u8 cfg_type, + u32 ioresource_types, int *bars) +{ + int pos; + + for (pos = pci_find_capability(dev, PCI_CAP_ID_VNDR); + pos > 0; + pos = pci_find_next_capability(dev, pos, PCI_CAP_ID_VNDR)) { + u8 type, bar; + pci_read_config_byte(dev, pos + offsetof(struct virtio_pci_cap, + cfg_type), + &type); + pci_read_config_byte(dev, pos + offsetof(struct virtio_pci_cap, + bar), + &bar); + + /* Ignore structures with reserved BAR values */ + if (bar >= PCI_STD_NUM_BARS) + continue; + + if (type == cfg_type) { + if (pci_resource_len(dev, bar) && + pci_resource_flags(dev, bar) & ioresource_types) { + *bars |= (1 << bar); + return pos; + } + } + } + return 0; +} + +/* This is part of the ABI. Don't screw with it. */ +static inline void check_offsets(void) +{ + /* Note: disk space was harmed in compilation of this function. */ + BUILD_BUG_ON(VIRTIO_PCI_CAP_VNDR != + offsetof(struct virtio_pci_cap, cap_vndr)); + BUILD_BUG_ON(VIRTIO_PCI_CAP_NEXT != + offsetof(struct virtio_pci_cap, cap_next)); + BUILD_BUG_ON(VIRTIO_PCI_CAP_LEN != + offsetof(struct virtio_pci_cap, cap_len)); + BUILD_BUG_ON(VIRTIO_PCI_CAP_CFG_TYPE != + offsetof(struct virtio_pci_cap, cfg_type)); + BUILD_BUG_ON(VIRTIO_PCI_CAP_BAR != + offsetof(struct virtio_pci_cap, bar)); + BUILD_BUG_ON(VIRTIO_PCI_CAP_OFFSET != + offsetof(struct virtio_pci_cap, offset)); + BUILD_BUG_ON(VIRTIO_PCI_CAP_LENGTH != + offsetof(struct virtio_pci_cap, length)); + BUILD_BUG_ON(VIRTIO_PCI_NOTIFY_CAP_MULT != + offsetof(struct virtio_pci_notify_cap, + notify_off_multiplier)); + BUILD_BUG_ON(VIRTIO_PCI_COMMON_DFSELECT != + offsetof(struct virtio_pci_common_cfg, + device_feature_select)); + BUILD_BUG_ON(VIRTIO_PCI_COMMON_DF != + offsetof(struct virtio_pci_common_cfg, device_feature)); + BUILD_BUG_ON(VIRTIO_PCI_COMMON_GFSELECT != + offsetof(struct virtio_pci_common_cfg, + guest_feature_select)); + BUILD_BUG_ON(VIRTIO_PCI_COMMON_GF != + offsetof(struct virtio_pci_common_cfg, guest_feature)); + BUILD_BUG_ON(VIRTIO_PCI_COMMON_MSIX != + offsetof(struct virtio_pci_common_cfg, msix_config)); + BUILD_BUG_ON(VIRTIO_PCI_COMMON_NUMQ != + offsetof(struct virtio_pci_common_cfg, num_queues)); + BUILD_BUG_ON(VIRTIO_PCI_COMMON_STATUS != + offsetof(struct virtio_pci_common_cfg, device_status)); + BUILD_BUG_ON(VIRTIO_PCI_COMMON_CFGGENERATION != + offsetof(struct virtio_pci_common_cfg, config_generation)); + BUILD_BUG_ON(VIRTIO_PCI_COMMON_Q_SELECT != + offsetof(struct virtio_pci_common_cfg, queue_select)); + BUILD_BUG_ON(VIRTIO_PCI_COMMON_Q_SIZE != + offsetof(struct virtio_pci_common_cfg, queue_size)); + BUILD_BUG_ON(VIRTIO_PCI_COMMON_Q_MSIX != + offsetof(struct virtio_pci_common_cfg, queue_msix_vector)); + BUILD_BUG_ON(VIRTIO_PCI_COMMON_Q_ENABLE != + offsetof(struct virtio_pci_common_cfg, queue_enable)); + BUILD_BUG_ON(VIRTIO_PCI_COMMON_Q_NOFF != + offsetof(struct virtio_pci_common_cfg, queue_notify_off)); + BUILD_BUG_ON(VIRTIO_PCI_COMMON_Q_DESCLO != + offsetof(struct virtio_pci_common_cfg, queue_desc_lo)); + BUILD_BUG_ON(VIRTIO_PCI_COMMON_Q_DESCHI != + offsetof(struct virtio_pci_common_cfg, queue_desc_hi)); + BUILD_BUG_ON(VIRTIO_PCI_COMMON_Q_AVAILLO != + offsetof(struct virtio_pci_common_cfg, queue_avail_lo)); + BUILD_BUG_ON(VIRTIO_PCI_COMMON_Q_AVAILHI != + offsetof(struct virtio_pci_common_cfg, queue_avail_hi)); + BUILD_BUG_ON(VIRTIO_PCI_COMMON_Q_USEDLO != + offsetof(struct virtio_pci_common_cfg, queue_used_lo)); + BUILD_BUG_ON(VIRTIO_PCI_COMMON_Q_USEDHI != + offsetof(struct virtio_pci_common_cfg, queue_used_hi)); + BUILD_BUG_ON(VIRTIO_PCI_COMMON_Q_NDATA != + offsetof(struct virtio_pci_modern_common_cfg, queue_notify_data)); + BUILD_BUG_ON(VIRTIO_PCI_COMMON_Q_RESET != + offsetof(struct virtio_pci_modern_common_cfg, queue_reset)); + BUILD_BUG_ON(VIRTIO_PCI_COMMON_ADM_Q_IDX != + offsetof(struct virtio_pci_modern_common_cfg, admin_queue_index)); + BUILD_BUG_ON(VIRTIO_PCI_COMMON_ADM_Q_NUM != + offsetof(struct virtio_pci_modern_common_cfg, admin_queue_num)); +} + +/* + * vp_modern_probe: probe the modern virtio pci device, note that the + * caller is required to enable PCI device before calling this function. + * @mdev: the modern virtio-pci device + * + * Return 0 on succeed otherwise fail + */ +int vp_modern_probe(struct virtio_pci_modern_device *mdev) +{ + struct pci_dev *pci_dev = mdev->pci_dev; + int err, common, isr, notify, device; + u32 notify_length; + u32 notify_offset; + int devid; + + check_offsets(); + + if (mdev->device_id_check) { + devid = mdev->device_id_check(pci_dev); + if (devid < 0) + return devid; + mdev->id.device = devid; + } else { + /* We only own devices >= 0x1000 and <= 0x107f: leave the rest. */ + if (pci_dev->device < 0x1000 || pci_dev->device > 0x107f) + return -ENODEV; + + if (pci_dev->device < 0x1040) { + /* Transitional devices: use the PCI subsystem device id as + * virtio device id, same as legacy driver always did. + */ + mdev->id.device = pci_dev->subsystem_device; + } else { + /* Modern devices: simply use PCI device id, but start from 0x1040. */ + mdev->id.device = pci_dev->device - 0x1040; + } + } + mdev->id.vendor = pci_dev->subsystem_vendor; + + /* check for a common config: if not, use legacy mode (bar 0). */ + common = virtio_pci_find_capability(pci_dev, VIRTIO_PCI_CAP_COMMON_CFG, + IORESOURCE_IO | IORESOURCE_MEM, + &mdev->modern_bars); + if (!common) { + dev_info(&pci_dev->dev, + "virtio_pci: leaving for legacy driver\n"); + return -ENODEV; + } + + /* If common is there, these should be too... */ + isr = virtio_pci_find_capability(pci_dev, VIRTIO_PCI_CAP_ISR_CFG, + IORESOURCE_IO | IORESOURCE_MEM, + &mdev->modern_bars); + notify = virtio_pci_find_capability(pci_dev, VIRTIO_PCI_CAP_NOTIFY_CFG, + IORESOURCE_IO | IORESOURCE_MEM, + &mdev->modern_bars); + if (!isr || !notify) { + dev_err(&pci_dev->dev, + "virtio_pci: missing capabilities %i/%i/%i\n", + common, isr, notify); + return -EINVAL; + } + + err = dma_set_mask_and_coherent(&pci_dev->dev, + mdev->dma_mask ? : DMA_BIT_MASK(64)); + if (err) + err = dma_set_mask_and_coherent(&pci_dev->dev, + DMA_BIT_MASK(32)); + if (err) + dev_warn(&pci_dev->dev, "Failed to enable 64-bit or 32-bit DMA. Trying to continue, but this might not work.\n"); + + /* Device capability is only mandatory for devices that have + * device-specific configuration. + */ + device = virtio_pci_find_capability(pci_dev, VIRTIO_PCI_CAP_DEVICE_CFG, + IORESOURCE_IO | IORESOURCE_MEM, + &mdev->modern_bars); + + err = pci_request_selected_regions(pci_dev, mdev->modern_bars, + "virtio-pci-modern"); + if (err) + return err; + + err = -EINVAL; + mdev->common = vp_modern_map_capability(mdev, common, + sizeof(struct virtio_pci_common_cfg), 4, 0, + offsetofend(struct virtio_pci_modern_common_cfg, + admin_queue_num), + &mdev->common_len, NULL); + if (!mdev->common) + goto err_map_common; + mdev->isr = vp_modern_map_capability(mdev, isr, sizeof(u8), 1, + 0, 1, + NULL, NULL); + if (!mdev->isr) + goto err_map_isr; + + /* Read notify_off_multiplier from config space. */ + pci_read_config_dword(pci_dev, + notify + offsetof(struct virtio_pci_notify_cap, + notify_off_multiplier), + &mdev->notify_offset_multiplier); + /* Read notify length and offset from config space. */ + pci_read_config_dword(pci_dev, + notify + offsetof(struct virtio_pci_notify_cap, + cap.length), + ¬ify_length); + + pci_read_config_dword(pci_dev, + notify + offsetof(struct virtio_pci_notify_cap, + cap.offset), + ¬ify_offset); + + /* We don't know how many VQs we'll map, ahead of the time. + * If notify length is small, map it all now. + * Otherwise, map each VQ individually later. + */ + if ((u64)notify_length + (notify_offset % PAGE_SIZE) <= PAGE_SIZE) { + mdev->notify_base = vp_modern_map_capability(mdev, notify, + 2, 2, + 0, notify_length, + &mdev->notify_len, + &mdev->notify_pa); + if (!mdev->notify_base) + goto err_map_notify; + } else { + mdev->notify_map_cap = notify; + } + + /* Again, we don't know how much we should map, but PAGE_SIZE + * is more than enough for all existing devices. + */ + if (device) { + mdev->device = vp_modern_map_capability(mdev, device, 0, 4, + 0, PAGE_SIZE, + &mdev->device_len, + NULL); + if (!mdev->device) + goto err_map_device; + } + + return 0; + +err_map_device: + if (mdev->notify_base) + pci_iounmap(pci_dev, mdev->notify_base); +err_map_notify: + pci_iounmap(pci_dev, mdev->isr); +err_map_isr: + pci_iounmap(pci_dev, mdev->common); +err_map_common: + pci_release_selected_regions(pci_dev, mdev->modern_bars); + return err; +} +EXPORT_SYMBOL_GPL(vp_modern_probe); + +/* + * vp_modern_remove: remove and cleanup the modern virtio pci device + * @mdev: the modern virtio-pci device + */ +void vp_modern_remove(struct virtio_pci_modern_device *mdev) +{ + struct pci_dev *pci_dev = mdev->pci_dev; + + if (mdev->device) + pci_iounmap(pci_dev, mdev->device); + if (mdev->notify_base) + pci_iounmap(pci_dev, mdev->notify_base); + pci_iounmap(pci_dev, mdev->isr); + pci_iounmap(pci_dev, mdev->common); + pci_release_selected_regions(pci_dev, mdev->modern_bars); +} +EXPORT_SYMBOL_GPL(vp_modern_remove); + +/* + * vp_modern_get_extended_features - get features from device + * @mdev: the modern virtio-pci device + * @features: the features array to be filled + * + * Fill the specified features array with the features read from the device + */ +void vp_modern_get_extended_features(struct virtio_pci_modern_device *mdev, + u64 *features) +{ + struct virtio_pci_common_cfg __iomem *cfg = mdev->common; + int i; + + virtio_features_zero(features); + for (i = 0; i < VIRTIO_FEATURES_BITS / 32; i++) { + u64 cur; + + vp_iowrite32(i, &cfg->device_feature_select); + cur = vp_ioread32(&cfg->device_feature); + features[i >> 1] |= cur << (32 * (i & 1)); + } +} +EXPORT_SYMBOL_GPL(vp_modern_get_extended_features); + +/* + * vp_modern_get_driver_features - get driver features from device + * @mdev: the modern virtio-pci device + * @features: the features array to be filled + * + * Fill the specified features array with the driver features read from the + * device + */ +void +vp_modern_get_driver_extended_features(struct virtio_pci_modern_device *mdev, + u64 *features) +{ + struct virtio_pci_common_cfg __iomem *cfg = mdev->common; + int i; + + virtio_features_zero(features); + for (i = 0; i < VIRTIO_FEATURES_BITS / 32; i++) { + u64 cur; + + vp_iowrite32(i, &cfg->guest_feature_select); + cur = vp_ioread32(&cfg->guest_feature); + features[i >> 1] |= cur << (32 * (i & 1)); + } +} +EXPORT_SYMBOL_GPL(vp_modern_get_driver_extended_features); + +/* + * vp_modern_set_extended_features - set features to device + * @mdev: the modern virtio-pci device + * @features: the features set to device + */ +void vp_modern_set_extended_features(struct virtio_pci_modern_device *mdev, + const u64 *features) +{ + struct virtio_pci_common_cfg __iomem *cfg = mdev->common; + int i; + + for (i = 0; i < VIRTIO_FEATURES_BITS / 32; i++) { + u32 cur = features[i >> 1] >> (32 * (i & 1)); + + vp_iowrite32(i, &cfg->guest_feature_select); + vp_iowrite32(cur, &cfg->guest_feature); + } +} +EXPORT_SYMBOL_GPL(vp_modern_set_extended_features); + +/* + * vp_modern_generation - get the device genreation + * @mdev: the modern virtio-pci device + * + * Returns the genreation read from device + */ +u32 vp_modern_generation(struct virtio_pci_modern_device *mdev) +{ + struct virtio_pci_common_cfg __iomem *cfg = mdev->common; + + return vp_ioread8(&cfg->config_generation); +} +EXPORT_SYMBOL_GPL(vp_modern_generation); + +/* + * vp_modern_get_status - get the device status + * @mdev: the modern virtio-pci device + * + * Returns the status read from device + */ +u8 vp_modern_get_status(struct virtio_pci_modern_device *mdev) +{ + struct virtio_pci_common_cfg __iomem *cfg = mdev->common; + + return vp_ioread8(&cfg->device_status); +} +EXPORT_SYMBOL_GPL(vp_modern_get_status); + +/* + * vp_modern_set_status - set status to device + * @mdev: the modern virtio-pci device + * @status: the status set to device + */ +void vp_modern_set_status(struct virtio_pci_modern_device *mdev, + u8 status) +{ + struct virtio_pci_common_cfg __iomem *cfg = mdev->common; + + /* + * Per memory-barriers.txt, wmb() is not needed to guarantee + * that the cache coherent memory writes have completed + * before writing to the MMIO region. + */ + vp_iowrite8(status, &cfg->device_status); +} +EXPORT_SYMBOL_GPL(vp_modern_set_status); + +/* + * vp_modern_get_queue_reset - get the queue reset status + * @mdev: the modern virtio-pci device + * @index: queue index + */ +int vp_modern_get_queue_reset(struct virtio_pci_modern_device *mdev, u16 index) +{ + struct virtio_pci_modern_common_cfg __iomem *cfg; + + cfg = (struct virtio_pci_modern_common_cfg __iomem *)mdev->common; + + vp_iowrite16(index, &cfg->cfg.queue_select); + return vp_ioread16(&cfg->queue_reset); +} +EXPORT_SYMBOL_GPL(vp_modern_get_queue_reset); + +/* + * vp_modern_set_queue_reset - reset the queue + * @mdev: the modern virtio-pci device + * @index: queue index + */ +void vp_modern_set_queue_reset(struct virtio_pci_modern_device *mdev, u16 index) +{ + struct virtio_pci_modern_common_cfg __iomem *cfg; + + cfg = (struct virtio_pci_modern_common_cfg __iomem *)mdev->common; + + vp_iowrite16(index, &cfg->cfg.queue_select); + vp_iowrite16(1, &cfg->queue_reset); + + while (vp_ioread16(&cfg->queue_reset)) + msleep(1); + + while (vp_ioread16(&cfg->cfg.queue_enable)) + msleep(1); +} +EXPORT_SYMBOL_GPL(vp_modern_set_queue_reset); + +/* + * vp_modern_queue_vector - set the MSIX vector for a specific virtqueue + * @mdev: the modern virtio-pci device + * @index: queue index + * @vector: the queue vector + * + * Returns the queue vector read from the device + */ +u16 vp_modern_queue_vector(struct virtio_pci_modern_device *mdev, + u16 index, u16 vector) +{ + struct virtio_pci_common_cfg __iomem *cfg = mdev->common; + + vp_iowrite16(index, &cfg->queue_select); + vp_iowrite16(vector, &cfg->queue_msix_vector); + /* Flush the write out to device */ + return vp_ioread16(&cfg->queue_msix_vector); +} +EXPORT_SYMBOL_GPL(vp_modern_queue_vector); + +/* + * vp_modern_config_vector - set the vector for config interrupt + * @mdev: the modern virtio-pci device + * @vector: the config vector + * + * Returns the config vector read from the device + */ +u16 vp_modern_config_vector(struct virtio_pci_modern_device *mdev, + u16 vector) +{ + struct virtio_pci_common_cfg __iomem *cfg = mdev->common; + + /* Setup the vector used for configuration events */ + vp_iowrite16(vector, &cfg->msix_config); + /* Verify we had enough resources to assign the vector */ + /* Will also flush the write out to device */ + return vp_ioread16(&cfg->msix_config); +} +EXPORT_SYMBOL_GPL(vp_modern_config_vector); + +/* + * vp_modern_queue_address - set the virtqueue address + * @mdev: the modern virtio-pci device + * @index: the queue index + * @desc_addr: address of the descriptor area + * @driver_addr: address of the driver area + * @device_addr: address of the device area + */ +void vp_modern_queue_address(struct virtio_pci_modern_device *mdev, + u16 index, u64 desc_addr, u64 driver_addr, + u64 device_addr) +{ + struct virtio_pci_common_cfg __iomem *cfg = mdev->common; + + vp_iowrite16(index, &cfg->queue_select); + + vp_iowrite64_twopart(desc_addr, &cfg->queue_desc_lo, + &cfg->queue_desc_hi); + vp_iowrite64_twopart(driver_addr, &cfg->queue_avail_lo, + &cfg->queue_avail_hi); + vp_iowrite64_twopart(device_addr, &cfg->queue_used_lo, + &cfg->queue_used_hi); +} +EXPORT_SYMBOL_GPL(vp_modern_queue_address); + +/* + * vp_modern_set_queue_enable - enable a virtqueue + * @mdev: the modern virtio-pci device + * @index: the queue index + * @enable: whether the virtqueue is enable or not + */ +void vp_modern_set_queue_enable(struct virtio_pci_modern_device *mdev, + u16 index, bool enable) +{ + vp_iowrite16(index, &mdev->common->queue_select); + vp_iowrite16(enable, &mdev->common->queue_enable); +} +EXPORT_SYMBOL_GPL(vp_modern_set_queue_enable); + +/* + * vp_modern_get_queue_enable - enable a virtqueue + * @mdev: the modern virtio-pci device + * @index: the queue index + * + * Returns whether a virtqueue is enabled or not + */ +bool vp_modern_get_queue_enable(struct virtio_pci_modern_device *mdev, + u16 index) +{ + vp_iowrite16(index, &mdev->common->queue_select); + + return vp_ioread16(&mdev->common->queue_enable); +} +EXPORT_SYMBOL_GPL(vp_modern_get_queue_enable); + +/* + * vp_modern_set_queue_size - set size for a virtqueue + * @mdev: the modern virtio-pci device + * @index: the queue index + * @size: the size of the virtqueue + */ +void vp_modern_set_queue_size(struct virtio_pci_modern_device *mdev, + u16 index, u16 size) +{ + vp_iowrite16(index, &mdev->common->queue_select); + vp_iowrite16(size, &mdev->common->queue_size); + +} +EXPORT_SYMBOL_GPL(vp_modern_set_queue_size); + +/* + * vp_modern_get_queue_size - get size for a virtqueue + * @mdev: the modern virtio-pci device + * @index: the queue index + * + * Returns the size of the virtqueue + */ +u16 vp_modern_get_queue_size(struct virtio_pci_modern_device *mdev, + u16 index) +{ + vp_iowrite16(index, &mdev->common->queue_select); + + return vp_ioread16(&mdev->common->queue_size); + +} +EXPORT_SYMBOL_GPL(vp_modern_get_queue_size); + +/* + * vp_modern_get_num_queues - get the number of virtqueues + * @mdev: the modern virtio-pci device + * + * Returns the number of virtqueues + */ +u16 vp_modern_get_num_queues(struct virtio_pci_modern_device *mdev) +{ + return vp_ioread16(&mdev->common->num_queues); +} +EXPORT_SYMBOL_GPL(vp_modern_get_num_queues); + +/* + * vp_modern_get_queue_notify_off - get notification offset for a virtqueue + * @mdev: the modern virtio-pci device + * @index: the queue index + * + * Returns the notification offset for a virtqueue + */ +static u16 vp_modern_get_queue_notify_off(struct virtio_pci_modern_device *mdev, + u16 index) +{ + vp_iowrite16(index, &mdev->common->queue_select); + + return vp_ioread16(&mdev->common->queue_notify_off); +} + +/* + * vp_modern_map_vq_notify - map notification area for a + * specific virtqueue + * @mdev: the modern virtio-pci device + * @index: the queue index + * @pa: the pointer to the physical address of the nofity area + * + * Returns the address of the notification area + */ +void __iomem *vp_modern_map_vq_notify(struct virtio_pci_modern_device *mdev, + u16 index, resource_size_t *pa) +{ + u16 off = vp_modern_get_queue_notify_off(mdev, index); + + if (mdev->notify_base) { + /* offset should not wrap */ + if ((u64)off * mdev->notify_offset_multiplier + 2 + > mdev->notify_len) { + dev_warn(&mdev->pci_dev->dev, + "bad notification offset %u (x %u) " + "for queue %u > %zd", + off, mdev->notify_offset_multiplier, + index, mdev->notify_len); + return NULL; + } + if (pa) + *pa = mdev->notify_pa + + off * mdev->notify_offset_multiplier; + return mdev->notify_base + off * mdev->notify_offset_multiplier; + } else { + return vp_modern_map_capability(mdev, + mdev->notify_map_cap, 2, 2, + off * mdev->notify_offset_multiplier, 2, + NULL, pa); + } +} +EXPORT_SYMBOL_GPL(vp_modern_map_vq_notify); + +u16 vp_modern_avq_num(struct virtio_pci_modern_device *mdev) +{ + struct virtio_pci_modern_common_cfg __iomem *cfg; + + cfg = (struct virtio_pci_modern_common_cfg __iomem *)mdev->common; + return vp_ioread16(&cfg->admin_queue_num); +} +EXPORT_SYMBOL_GPL(vp_modern_avq_num); + +u16 vp_modern_avq_index(struct virtio_pci_modern_device *mdev) +{ + struct virtio_pci_modern_common_cfg __iomem *cfg; + + cfg = (struct virtio_pci_modern_common_cfg __iomem *)mdev->common; + return vp_ioread16(&cfg->admin_queue_index); +} +EXPORT_SYMBOL_GPL(vp_modern_avq_index); + +MODULE_VERSION("0.1"); +MODULE_DESCRIPTION("Modern Virtio PCI Device"); +MODULE_AUTHOR("Jason Wang <jasowang@redhat.com>"); +MODULE_LICENSE("GPL"); diff --git a/drivers/virtio/virtio_ring.c b/drivers/virtio/virtio_ring.c index 6b4a4db4404d..ddab68959671 100644 --- a/drivers/virtio/virtio_ring.c +++ b/drivers/virtio/virtio_ring.c @@ -1,20 +1,7 @@ +// SPDX-License-Identifier: GPL-2.0-or-later /* Virtio ring implementation. * * Copyright 2007 Rusty Russell IBM Corporation - * - * This program is free software; you can redistribute it and/or modify - * it under the terms of the GNU General Public License as published by - * the Free Software Foundation; either version 2 of the License, or - * (at your option) any later version. - * - * This program is distributed in the hope that it will be useful, - * but WITHOUT ANY WARRANTY; without even the implied warranty of - * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the - * GNU General Public License for more details. - * - * You should have received a copy of the GNU General Public License - * along with this program; if not, write to the Free Software - * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA */ #include <linux/virtio.h> #include <linux/virtio_ring.h> @@ -23,6 +10,10 @@ #include <linux/slab.h> #include <linux/module.h> #include <linux/hrtimer.h> +#include <linux/dma-mapping.h> +#include <linux/kmsan.h> +#include <linux/spinlock.h> +#include <xen/xen.h> #ifdef DEBUG /* For development, we want to crash whenever the ring is screwed. */ @@ -42,6 +33,26 @@ } while (0) #define END_USE(_vq) \ do { BUG_ON(!(_vq)->in_use); (_vq)->in_use = 0; } while(0) +#define LAST_ADD_TIME_UPDATE(_vq) \ + do { \ + ktime_t now = ktime_get(); \ + \ + /* No kick or get, with .1 second between? Warn. */ \ + if ((_vq)->last_add_time_valid) \ + WARN_ON(ktime_to_ms(ktime_sub(now, \ + (_vq)->last_add_time)) > 100); \ + (_vq)->last_add_time = now; \ + (_vq)->last_add_time_valid = true; \ + } while (0) +#define LAST_ADD_TIME_CHECK(_vq) \ + do { \ + if ((_vq)->last_add_time_valid) { \ + WARN_ON(ktime_to_ms(ktime_sub(ktime_get(), \ + (_vq)->last_add_time)) > 100); \ + } \ + } while (0) +#define LAST_ADD_TIME_INVALID(_vq) \ + ((_vq)->last_add_time_valid = false) #else #define BAD_RING(_vq, fmt, args...) \ do { \ @@ -51,15 +62,112 @@ } while (0) #define START_USE(vq) #define END_USE(vq) +#define LAST_ADD_TIME_UPDATE(vq) +#define LAST_ADD_TIME_CHECK(vq) +#define LAST_ADD_TIME_INVALID(vq) #endif -struct vring_virtqueue -{ - struct virtqueue vq; +struct vring_desc_state_split { + void *data; /* Data for callback. */ - /* Actual memory layout for this queue */ + /* Indirect desc table and extra table, if any. These two will be + * allocated together. So we won't stress more to the memory allocator. + */ + struct vring_desc *indir_desc; +}; + +struct vring_desc_state_packed { + void *data; /* Data for callback. */ + + /* Indirect desc table and extra table, if any. These two will be + * allocated together. So we won't stress more to the memory allocator. + */ + struct vring_packed_desc *indir_desc; + u16 num; /* Descriptor list length. */ + u16 last; /* The last desc state in a list. */ +}; + +struct vring_desc_extra { + dma_addr_t addr; /* Descriptor DMA addr. */ + u32 len; /* Descriptor length. */ + u16 flags; /* Descriptor flags. */ + u16 next; /* The next desc state in a list. */ +}; + +struct vring_virtqueue_split { + /* Actual memory layout for this queue. */ struct vring vring; + /* Last written value to avail->flags */ + u16 avail_flags_shadow; + + /* + * Last written value to avail->idx in + * guest byte order. + */ + u16 avail_idx_shadow; + + /* Per-descriptor state. */ + struct vring_desc_state_split *desc_state; + struct vring_desc_extra *desc_extra; + + /* DMA address and size information */ + dma_addr_t queue_dma_addr; + size_t queue_size_in_bytes; + + /* + * The parameters for creating vrings are reserved for creating new + * vring. + */ + u32 vring_align; + bool may_reduce_num; +}; + +struct vring_virtqueue_packed { + /* Actual memory layout for this queue. */ + struct { + unsigned int num; + struct vring_packed_desc *desc; + struct vring_packed_desc_event *driver; + struct vring_packed_desc_event *device; + } vring; + + /* Driver ring wrap counter. */ + bool avail_wrap_counter; + + /* Avail used flags. */ + u16 avail_used_flags; + + /* Index of the next avail descriptor. */ + u16 next_avail_idx; + + /* + * Last written value to driver->flags in + * guest byte order. + */ + u16 event_flags_shadow; + + /* Per-descriptor state. */ + struct vring_desc_state_packed *desc_state; + struct vring_desc_extra *desc_extra; + + /* DMA address and size information */ + dma_addr_t ring_dma_addr; + dma_addr_t driver_event_dma_addr; + dma_addr_t device_event_dma_addr; + size_t ring_size_in_bytes; + size_t event_size_in_bytes; +}; + +struct vring_virtqueue { + struct virtqueue vq; + + /* Is this a packed ring? */ + bool packed_ring; + + /* Is DMA API used? */ + bool use_map_api; + /* Can we use weak barriers? */ bool weak_barriers; @@ -77,11 +185,32 @@ struct vring_virtqueue /* Number we've added since last sync. */ unsigned int num_added; - /* Last used index we've seen. */ + /* Last used index we've seen. + * for split ring, it just contains last used index + * for packed ring: + * bits up to VRING_PACKED_EVENT_F_WRAP_CTR include the last used index. + * bits from VRING_PACKED_EVENT_F_WRAP_CTR include the used wrap counter. + */ u16 last_used_idx; + /* Hint for event idx: already triggered no need to disable. */ + bool event_triggered; + + union { + /* Available for split ring */ + struct vring_virtqueue_split split; + + /* Available for packed ring */ + struct vring_virtqueue_packed packed; + }; + /* How to notify other side. FIXME: commonalize hcalls! */ - void (*notify)(struct virtqueue *vq); + bool (*notify)(struct virtqueue *vq); + + /* DMA, allocation, and size information */ + bool we_own_ring; + + union virtio_map map; #ifdef DEBUG /* They're supposed to lock for us. */ @@ -91,223 +220,2085 @@ struct vring_virtqueue bool last_add_time_valid; ktime_t last_add_time; #endif - - /* Tokens for callbacks. */ - void *data[]; }; -#define to_vvq(_vq) container_of(_vq, struct vring_virtqueue, vq) +static struct vring_desc_extra *vring_alloc_desc_extra(unsigned int num); +static void vring_free(struct virtqueue *_vq); -static inline struct scatterlist *sg_next_chained(struct scatterlist *sg, - unsigned int *count) +/* + * Helpers. + */ + +#define to_vvq(_vq) container_of_const(_vq, struct vring_virtqueue, vq) + +static bool virtqueue_use_indirect(const struct vring_virtqueue *vq, + unsigned int total_sg) { - return sg_next(sg); + /* + * If the host supports indirect descriptor tables, and we have multiple + * buffers, then go indirect. FIXME: tune this threshold + */ + return (vq->indirect && total_sg > 1 && vq->vq.num_free); } -static inline struct scatterlist *sg_next_arr(struct scatterlist *sg, - unsigned int *count) +/* + * Modern virtio devices have feature bits to specify whether they need a + * quirk and bypass the IOMMU. If not there, just use the DMA API. + * + * If there, the interaction between virtio and DMA API is messy. + * + * On most systems with virtio, physical addresses match bus addresses, + * and it doesn't particularly matter whether we use the DMA API. + * + * On some systems, including Xen and any system with a physical device + * that speaks virtio behind a physical IOMMU, we must use the DMA API + * for virtio DMA to work at all. + * + * On other systems, including SPARC and PPC64, virtio-pci devices are + * enumerated as though they are behind an IOMMU, but the virtio host + * ignores the IOMMU, so we must either pretend that the IOMMU isn't + * there or somehow map everything as the identity. + * + * For the time being, we preserve historic behavior and bypass the DMA + * API. + * + * TODO: install a per-device DMA ops structure that does the right thing + * taking into account all the above quirks, and use the DMA API + * unconditionally on data path. + */ + +static bool vring_use_map_api(const struct virtio_device *vdev) { - if (--(*count) == 0) - return NULL; - return sg + 1; + if (!virtio_has_dma_quirk(vdev)) + return true; + + /* Otherwise, we are left to guess. */ + /* + * In theory, it's possible to have a buggy QEMU-supposed + * emulated Q35 IOMMU and Xen enabled at the same time. On + * such a configuration, virtio has never worked and will + * not work without an even larger kludge. Instead, enable + * the DMA API if we're a Xen guest, which at least allows + * all of the sensible Xen configurations to work correctly. + */ + if (xen_domain()) + return true; + + return false; +} + +static bool vring_need_unmap_buffer(const struct vring_virtqueue *vring, + const struct vring_desc_extra *extra) +{ + return vring->use_map_api && (extra->addr != DMA_MAPPING_ERROR); +} + +size_t virtio_max_dma_size(const struct virtio_device *vdev) +{ + size_t max_segment_size = SIZE_MAX; + + if (vring_use_map_api(vdev)) { + if (vdev->map) { + max_segment_size = + vdev->map->max_mapping_size(vdev->vmap); + } else + max_segment_size = + dma_max_mapping_size(vdev->dev.parent); + } + + return max_segment_size; +} +EXPORT_SYMBOL_GPL(virtio_max_dma_size); + +static void *vring_alloc_queue(struct virtio_device *vdev, size_t size, + dma_addr_t *map_handle, gfp_t flag, + union virtio_map map) +{ + if (vring_use_map_api(vdev)) { + return virtqueue_map_alloc_coherent(vdev, map, size, + map_handle, flag); + } else { + void *queue = alloc_pages_exact(PAGE_ALIGN(size), flag); + + if (queue) { + phys_addr_t phys_addr = virt_to_phys(queue); + *map_handle = (dma_addr_t)phys_addr; + + /* + * Sanity check: make sure we dind't truncate + * the address. The only arches I can find that + * have 64-bit phys_addr_t but 32-bit dma_addr_t + * are certain non-highmem MIPS and x86 + * configurations, but these configurations + * should never allocate physical pages above 32 + * bits, so this is fine. Just in case, throw a + * warning and abort if we end up with an + * unrepresentable address. + */ + if (WARN_ON_ONCE(*map_handle != phys_addr)) { + free_pages_exact(queue, PAGE_ALIGN(size)); + return NULL; + } + } + return queue; + } } -/* Set up an indirect table of descriptors and add it to the queue. */ -static inline int vring_add_indirect(struct vring_virtqueue *vq, - struct scatterlist *sgs[], - struct scatterlist *(*next) - (struct scatterlist *, unsigned int *), - unsigned int total_sg, - unsigned int total_out, - unsigned int total_in, - unsigned int out_sgs, - unsigned int in_sgs, - gfp_t gfp) +static void vring_free_queue(struct virtio_device *vdev, size_t size, + void *queue, dma_addr_t map_handle, + union virtio_map map) { + if (vring_use_map_api(vdev)) + virtqueue_map_free_coherent(vdev, map, size, + queue, map_handle); + else + free_pages_exact(queue, PAGE_ALIGN(size)); +} + +/* + * The DMA ops on various arches are rather gnarly right now, and + * making all of the arch DMA ops work on the vring device itself + * is a mess. + */ +static struct device *vring_dma_dev(const struct vring_virtqueue *vq) +{ + return vq->map.dma_dev; +} + +static int vring_mapping_error(const struct vring_virtqueue *vq, + dma_addr_t addr) +{ + struct virtio_device *vdev = vq->vq.vdev; + + if (!vq->use_map_api) + return 0; + + if (vdev->map) + return vdev->map->mapping_error(vq->map, addr); + else + return dma_mapping_error(vring_dma_dev(vq), addr); +} + +/* Map one sg entry. */ +static int vring_map_one_sg(const struct vring_virtqueue *vq, struct scatterlist *sg, + enum dma_data_direction direction, dma_addr_t *addr, + u32 *len, bool premapped) +{ + if (premapped) { + *addr = sg_dma_address(sg); + *len = sg_dma_len(sg); + return 0; + } + + *len = sg->length; + + if (!vq->use_map_api) { + /* + * If DMA is not used, KMSAN doesn't know that the scatterlist + * is initialized by the hardware. Explicitly check/unpoison it + * depending on the direction. + */ + kmsan_handle_dma(sg_phys(sg), sg->length, direction); + *addr = (dma_addr_t)sg_phys(sg); + return 0; + } + + /* + * We can't use dma_map_sg, because we don't use scatterlists in + * the way it expects (we don't guarantee that the scatterlist + * will exist for the lifetime of the mapping). + */ + *addr = virtqueue_map_page_attrs(&vq->vq, sg_page(sg), + sg->offset, sg->length, + direction, 0); + + if (vring_mapping_error(vq, *addr)) + return -ENOMEM; + + return 0; +} + +static dma_addr_t vring_map_single(const struct vring_virtqueue *vq, + void *cpu_addr, size_t size, + enum dma_data_direction direction) +{ + if (!vq->use_map_api) + return (dma_addr_t)virt_to_phys(cpu_addr); + + return virtqueue_map_single_attrs(&vq->vq, cpu_addr, + size, direction, 0); +} + +static void virtqueue_init(struct vring_virtqueue *vq, u32 num) +{ + vq->vq.num_free = num; + + if (vq->packed_ring) + vq->last_used_idx = 0 | (1 << VRING_PACKED_EVENT_F_WRAP_CTR); + else + vq->last_used_idx = 0; + + vq->event_triggered = false; + vq->num_added = 0; + +#ifdef DEBUG + vq->in_use = false; + vq->last_add_time_valid = false; +#endif +} + + +/* + * Split ring specific functions - *_split(). + */ + +static unsigned int vring_unmap_one_split(const struct vring_virtqueue *vq, + struct vring_desc_extra *extra) +{ + u16 flags; + + flags = extra->flags; + + if (flags & VRING_DESC_F_INDIRECT) { + if (!vq->use_map_api) + goto out; + } else if (!vring_need_unmap_buffer(vq, extra)) + goto out; + + virtqueue_unmap_page_attrs(&vq->vq, + extra->addr, + extra->len, + (flags & VRING_DESC_F_WRITE) ? + DMA_FROM_DEVICE : DMA_TO_DEVICE, + 0); + +out: + return extra->next; +} + +static struct vring_desc *alloc_indirect_split(struct virtqueue *_vq, + unsigned int total_sg, + gfp_t gfp) +{ + struct vring_desc_extra *extra; struct vring_desc *desc; - unsigned head; - struct scatterlist *sg; - int i, n; + unsigned int i, size; /* * We require lowmem mappings for the descriptors because * otherwise virt_to_phys will give us bogus addresses in the * virtqueue. */ - gfp &= ~(__GFP_HIGHMEM | __GFP_HIGH); + gfp &= ~__GFP_HIGHMEM; - desc = kmalloc(total_sg * sizeof(struct vring_desc), gfp); + size = sizeof(*desc) * total_sg + sizeof(*extra) * total_sg; + + desc = kmalloc(size, gfp); if (!desc) - return -ENOMEM; + return NULL; - /* Transfer entries from the sg lists into the indirect page */ - i = 0; - for (n = 0; n < out_sgs; n++) { - for (sg = sgs[n]; sg; sg = next(sg, &total_out)) { - desc[i].flags = VRING_DESC_F_NEXT; - desc[i].addr = sg_phys(sg); - desc[i].len = sg->length; - desc[i].next = i+1; - i++; - } - } - for (; n < (out_sgs + in_sgs); n++) { - for (sg = sgs[n]; sg; sg = next(sg, &total_in)) { - desc[i].flags = VRING_DESC_F_NEXT|VRING_DESC_F_WRITE; - desc[i].addr = sg_phys(sg); - desc[i].len = sg->length; - desc[i].next = i+1; - i++; - } - } - BUG_ON(i != total_sg); + extra = (struct vring_desc_extra *)&desc[total_sg]; - /* Last one doesn't continue. */ - desc[i-1].flags &= ~VRING_DESC_F_NEXT; - desc[i-1].next = 0; + for (i = 0; i < total_sg; i++) + extra[i].next = i + 1; - /* We're about to use a buffer */ - vq->vq.num_free--; + return desc; +} - /* Use a single buffer which doesn't continue */ - head = vq->free_head; - vq->vring.desc[head].flags = VRING_DESC_F_INDIRECT; - vq->vring.desc[head].addr = virt_to_phys(desc); - vq->vring.desc[head].len = i * sizeof(struct vring_desc); +static inline unsigned int virtqueue_add_desc_split(struct virtqueue *vq, + struct vring_desc *desc, + struct vring_desc_extra *extra, + unsigned int i, + dma_addr_t addr, + unsigned int len, + u16 flags, bool premapped) +{ + u16 next; - /* Update free pointer */ - vq->free_head = vq->vring.desc[head].next; + desc[i].flags = cpu_to_virtio16(vq->vdev, flags); + desc[i].addr = cpu_to_virtio64(vq->vdev, addr); + desc[i].len = cpu_to_virtio32(vq->vdev, len); - return head; + extra[i].addr = premapped ? DMA_MAPPING_ERROR : addr; + extra[i].len = len; + extra[i].flags = flags; + + next = extra[i].next; + + desc[i].next = cpu_to_virtio16(vq->vdev, next); + + return next; } -static inline int virtqueue_add(struct virtqueue *_vq, - struct scatterlist *sgs[], - struct scatterlist *(*next) - (struct scatterlist *, unsigned int *), - unsigned int total_out, - unsigned int total_in, - unsigned int out_sgs, - unsigned int in_sgs, - void *data, - gfp_t gfp) +static inline int virtqueue_add_split(struct virtqueue *_vq, + struct scatterlist *sgs[], + unsigned int total_sg, + unsigned int out_sgs, + unsigned int in_sgs, + void *data, + void *ctx, + bool premapped, + gfp_t gfp) { struct vring_virtqueue *vq = to_vvq(_vq); + struct vring_desc_extra *extra; struct scatterlist *sg; - unsigned int i, n, avail, uninitialized_var(prev), total_sg; + struct vring_desc *desc; + unsigned int i, n, avail, descs_used, prev, err_idx; int head; + bool indirect; START_USE(vq); BUG_ON(data == NULL); + BUG_ON(ctx && vq->indirect); -#ifdef DEBUG - { - ktime_t now = ktime_get(); - - /* No kick or get, with .1 second between? Warn. */ - if (vq->last_add_time_valid) - WARN_ON(ktime_to_ms(ktime_sub(now, vq->last_add_time)) - > 100); - vq->last_add_time = now; - vq->last_add_time_valid = true; + if (unlikely(vq->broken)) { + END_USE(vq); + return -EIO; } -#endif - total_sg = total_in + total_out; + LAST_ADD_TIME_UPDATE(vq); + + BUG_ON(total_sg == 0); + + head = vq->free_head; - /* If the host supports indirect descriptor tables, and we have multiple - * buffers, then go indirect. FIXME: tune this threshold */ - if (vq->indirect && total_sg > 1 && vq->vq.num_free) { - head = vring_add_indirect(vq, sgs, next, total_sg, total_out, - total_in, - out_sgs, in_sgs, gfp); - if (likely(head >= 0)) - goto add_head; + if (virtqueue_use_indirect(vq, total_sg)) + desc = alloc_indirect_split(_vq, total_sg, gfp); + else { + desc = NULL; + WARN_ON_ONCE(total_sg > vq->split.vring.num && !vq->indirect); } - BUG_ON(total_sg > vq->vring.num); - BUG_ON(total_sg == 0); + if (desc) { + /* Use a single buffer which doesn't continue */ + indirect = true; + /* Set up rest to use this indirect table. */ + i = 0; + descs_used = 1; + extra = (struct vring_desc_extra *)&desc[total_sg]; + } else { + indirect = false; + desc = vq->split.vring.desc; + extra = vq->split.desc_extra; + i = head; + descs_used = total_sg; + } - if (vq->vq.num_free < total_sg) { + if (unlikely(vq->vq.num_free < descs_used)) { pr_debug("Can't add buf len %i - avail = %i\n", - total_sg, vq->vq.num_free); + descs_used, vq->vq.num_free); /* FIXME: for historical reasons, we force a notify here if * there are outgoing parts to the buffer. Presumably the * host should service the ring ASAP. */ if (out_sgs) vq->notify(&vq->vq); + if (indirect) + kfree(desc); END_USE(vq); return -ENOSPC; } - /* We're about to use some buffers from the free list. */ - vq->vq.num_free -= total_sg; - - head = i = vq->free_head; for (n = 0; n < out_sgs; n++) { - for (sg = sgs[n]; sg; sg = next(sg, &total_out)) { - vq->vring.desc[i].flags = VRING_DESC_F_NEXT; - vq->vring.desc[i].addr = sg_phys(sg); - vq->vring.desc[i].len = sg->length; + for (sg = sgs[n]; sg; sg = sg_next(sg)) { + dma_addr_t addr; + u32 len; + + if (vring_map_one_sg(vq, sg, DMA_TO_DEVICE, &addr, &len, premapped)) + goto unmap_release; + prev = i; - i = vq->vring.desc[i].next; + /* Note that we trust indirect descriptor + * table since it use stream DMA mapping. + */ + i = virtqueue_add_desc_split(_vq, desc, extra, i, addr, len, + VRING_DESC_F_NEXT, + premapped); } } for (; n < (out_sgs + in_sgs); n++) { - for (sg = sgs[n]; sg; sg = next(sg, &total_in)) { - vq->vring.desc[i].flags = VRING_DESC_F_NEXT|VRING_DESC_F_WRITE; - vq->vring.desc[i].addr = sg_phys(sg); - vq->vring.desc[i].len = sg->length; + for (sg = sgs[n]; sg; sg = sg_next(sg)) { + dma_addr_t addr; + u32 len; + + if (vring_map_one_sg(vq, sg, DMA_FROM_DEVICE, &addr, &len, premapped)) + goto unmap_release; + prev = i; - i = vq->vring.desc[i].next; + /* Note that we trust indirect descriptor + * table since it use stream DMA mapping. + */ + i = virtqueue_add_desc_split(_vq, desc, extra, i, addr, len, + VRING_DESC_F_NEXT | + VRING_DESC_F_WRITE, + premapped); } } /* Last one doesn't continue. */ - vq->vring.desc[prev].flags &= ~VRING_DESC_F_NEXT; + desc[prev].flags &= cpu_to_virtio16(_vq->vdev, ~VRING_DESC_F_NEXT); + if (!indirect && vring_need_unmap_buffer(vq, &extra[prev])) + vq->split.desc_extra[prev & (vq->split.vring.num - 1)].flags &= + ~VRING_DESC_F_NEXT; + + if (indirect) { + /* Now that the indirect table is filled in, map it. */ + dma_addr_t addr = vring_map_single( + vq, desc, total_sg * sizeof(struct vring_desc), + DMA_TO_DEVICE); + if (vring_mapping_error(vq, addr)) + goto unmap_release; + + virtqueue_add_desc_split(_vq, vq->split.vring.desc, + vq->split.desc_extra, + head, addr, + total_sg * sizeof(struct vring_desc), + VRING_DESC_F_INDIRECT, false); + } - /* Update free pointer */ - vq->free_head = i; + /* We're using some buffers from the free list. */ + vq->vq.num_free -= descs_used; -add_head: - /* Set token. */ - vq->data[head] = data; + /* Update free pointer */ + if (indirect) + vq->free_head = vq->split.desc_extra[head].next; + else + vq->free_head = i; + + /* Store token and indirect buffer state. */ + vq->split.desc_state[head].data = data; + if (indirect) + vq->split.desc_state[head].indir_desc = desc; + else + vq->split.desc_state[head].indir_desc = ctx; /* Put entry in available array (but don't update avail->idx until they * do sync). */ - avail = (vq->vring.avail->idx & (vq->vring.num-1)); - vq->vring.avail->ring[avail] = head; + avail = vq->split.avail_idx_shadow & (vq->split.vring.num - 1); + vq->split.vring.avail->ring[avail] = cpu_to_virtio16(_vq->vdev, head); /* Descriptors and available array need to be set before we expose the * new available array entries. */ virtio_wmb(vq->weak_barriers); - vq->vring.avail->idx++; + vq->split.avail_idx_shadow++; + vq->split.vring.avail->idx = cpu_to_virtio16(_vq->vdev, + vq->split.avail_idx_shadow); vq->num_added++; + pr_debug("Added buffer head %i to %p\n", head, vq); + END_USE(vq); + /* This is very unlikely, but theoretically possible. Kick * just in case. */ if (unlikely(vq->num_added == (1 << 16) - 1)) virtqueue_kick(_vq); + return 0; + +unmap_release: + err_idx = i; + + if (indirect) + i = 0; + else + i = head; + + for (n = 0; n < total_sg; n++) { + if (i == err_idx) + break; + + i = vring_unmap_one_split(vq, &extra[i]); + } + + if (indirect) + kfree(desc); + + END_USE(vq); + return -ENOMEM; +} + +static bool virtqueue_kick_prepare_split(struct virtqueue *_vq) +{ + struct vring_virtqueue *vq = to_vvq(_vq); + u16 new, old; + bool needs_kick; + + START_USE(vq); + /* We need to expose available array entries before checking avail + * event. */ + virtio_mb(vq->weak_barriers); + + old = vq->split.avail_idx_shadow - vq->num_added; + new = vq->split.avail_idx_shadow; + vq->num_added = 0; + + LAST_ADD_TIME_CHECK(vq); + LAST_ADD_TIME_INVALID(vq); + + if (vq->event) { + needs_kick = vring_need_event(virtio16_to_cpu(_vq->vdev, + vring_avail_event(&vq->split.vring)), + new, old); + } else { + needs_kick = !(vq->split.vring.used->flags & + cpu_to_virtio16(_vq->vdev, + VRING_USED_F_NO_NOTIFY)); + } + END_USE(vq); + return needs_kick; +} + +static void detach_buf_split(struct vring_virtqueue *vq, unsigned int head, + void **ctx) +{ + struct vring_desc_extra *extra; + unsigned int i, j; + __virtio16 nextflag = cpu_to_virtio16(vq->vq.vdev, VRING_DESC_F_NEXT); + + /* Clear data ptr. */ + vq->split.desc_state[head].data = NULL; + + extra = vq->split.desc_extra; + + /* Put back on free list: unmap first-level descriptors and find end */ + i = head; + + while (vq->split.vring.desc[i].flags & nextflag) { + vring_unmap_one_split(vq, &extra[i]); + i = vq->split.desc_extra[i].next; + vq->vq.num_free++; + } + + vring_unmap_one_split(vq, &extra[i]); + vq->split.desc_extra[i].next = vq->free_head; + vq->free_head = head; + + /* Plus final descriptor */ + vq->vq.num_free++; + + if (vq->indirect) { + struct vring_desc *indir_desc = + vq->split.desc_state[head].indir_desc; + u32 len, num; + + /* Free the indirect table, if any, now that it's unmapped. */ + if (!indir_desc) + return; + len = vq->split.desc_extra[head].len; + + BUG_ON(!(vq->split.desc_extra[head].flags & + VRING_DESC_F_INDIRECT)); + BUG_ON(len == 0 || len % sizeof(struct vring_desc)); + + num = len / sizeof(struct vring_desc); + + extra = (struct vring_desc_extra *)&indir_desc[num]; + + if (vq->use_map_api) { + for (j = 0; j < num; j++) + vring_unmap_one_split(vq, &extra[j]); + } + + kfree(indir_desc); + vq->split.desc_state[head].indir_desc = NULL; + } else if (ctx) { + *ctx = vq->split.desc_state[head].indir_desc; + } +} + +static bool more_used_split(const struct vring_virtqueue *vq) +{ + return vq->last_used_idx != virtio16_to_cpu(vq->vq.vdev, + vq->split.vring.used->idx); +} + +static void *virtqueue_get_buf_ctx_split(struct virtqueue *_vq, + unsigned int *len, + void **ctx) +{ + struct vring_virtqueue *vq = to_vvq(_vq); + void *ret; + unsigned int i; + u16 last_used; + + START_USE(vq); + + if (unlikely(vq->broken)) { + END_USE(vq); + return NULL; + } + + if (!more_used_split(vq)) { + pr_debug("No more buffers in queue\n"); + END_USE(vq); + return NULL; + } + + /* Only get used array entries after they have been exposed by host. */ + virtio_rmb(vq->weak_barriers); + + last_used = (vq->last_used_idx & (vq->split.vring.num - 1)); + i = virtio32_to_cpu(_vq->vdev, + vq->split.vring.used->ring[last_used].id); + *len = virtio32_to_cpu(_vq->vdev, + vq->split.vring.used->ring[last_used].len); + + if (unlikely(i >= vq->split.vring.num)) { + BAD_RING(vq, "id %u out of range\n", i); + return NULL; + } + if (unlikely(!vq->split.desc_state[i].data)) { + BAD_RING(vq, "id %u is not a head!\n", i); + return NULL; + } + + /* detach_buf_split clears data, so grab it now. */ + ret = vq->split.desc_state[i].data; + detach_buf_split(vq, i, ctx); + vq->last_used_idx++; + /* If we expect an interrupt for the next entry, tell host + * by writing event index and flush out the write before + * the read in the next get_buf call. */ + if (!(vq->split.avail_flags_shadow & VRING_AVAIL_F_NO_INTERRUPT)) + virtio_store_mb(vq->weak_barriers, + &vring_used_event(&vq->split.vring), + cpu_to_virtio16(_vq->vdev, vq->last_used_idx)); + + LAST_ADD_TIME_INVALID(vq); + + END_USE(vq); + return ret; +} + +static void virtqueue_disable_cb_split(struct virtqueue *_vq) +{ + struct vring_virtqueue *vq = to_vvq(_vq); + + if (!(vq->split.avail_flags_shadow & VRING_AVAIL_F_NO_INTERRUPT)) { + vq->split.avail_flags_shadow |= VRING_AVAIL_F_NO_INTERRUPT; + + /* + * If device triggered an event already it won't trigger one again: + * no need to disable. + */ + if (vq->event_triggered) + return; + + if (vq->event) + /* TODO: this is a hack. Figure out a cleaner value to write. */ + vring_used_event(&vq->split.vring) = 0x0; + else + vq->split.vring.avail->flags = + cpu_to_virtio16(_vq->vdev, + vq->split.avail_flags_shadow); + } +} + +static unsigned int virtqueue_enable_cb_prepare_split(struct virtqueue *_vq) +{ + struct vring_virtqueue *vq = to_vvq(_vq); + u16 last_used_idx; + + START_USE(vq); + + /* We optimistically turn back on interrupts, then check if there was + * more to do. */ + /* Depending on the VIRTIO_RING_F_EVENT_IDX feature, we need to + * either clear the flags bit or point the event index at the next + * entry. Always do both to keep code simple. */ + if (vq->split.avail_flags_shadow & VRING_AVAIL_F_NO_INTERRUPT) { + vq->split.avail_flags_shadow &= ~VRING_AVAIL_F_NO_INTERRUPT; + if (!vq->event) + vq->split.vring.avail->flags = + cpu_to_virtio16(_vq->vdev, + vq->split.avail_flags_shadow); + } + vring_used_event(&vq->split.vring) = cpu_to_virtio16(_vq->vdev, + last_used_idx = vq->last_used_idx); + END_USE(vq); + return last_used_idx; +} + +static bool virtqueue_poll_split(struct virtqueue *_vq, unsigned int last_used_idx) +{ + struct vring_virtqueue *vq = to_vvq(_vq); + + return (u16)last_used_idx != virtio16_to_cpu(_vq->vdev, + vq->split.vring.used->idx); +} + +static bool virtqueue_enable_cb_delayed_split(struct virtqueue *_vq) +{ + struct vring_virtqueue *vq = to_vvq(_vq); + u16 bufs; + + START_USE(vq); + + /* We optimistically turn back on interrupts, then check if there was + * more to do. */ + /* Depending on the VIRTIO_RING_F_USED_EVENT_IDX feature, we need to + * either clear the flags bit or point the event index at the next + * entry. Always update the event index to keep code simple. */ + if (vq->split.avail_flags_shadow & VRING_AVAIL_F_NO_INTERRUPT) { + vq->split.avail_flags_shadow &= ~VRING_AVAIL_F_NO_INTERRUPT; + if (!vq->event) + vq->split.vring.avail->flags = + cpu_to_virtio16(_vq->vdev, + vq->split.avail_flags_shadow); + } + /* TODO: tune this threshold */ + bufs = (u16)(vq->split.avail_idx_shadow - vq->last_used_idx) * 3 / 4; + + virtio_store_mb(vq->weak_barriers, + &vring_used_event(&vq->split.vring), + cpu_to_virtio16(_vq->vdev, vq->last_used_idx + bufs)); + + if (unlikely((u16)(virtio16_to_cpu(_vq->vdev, vq->split.vring.used->idx) + - vq->last_used_idx) > bufs)) { + END_USE(vq); + return false; + } + + END_USE(vq); + return true; +} + +static void *virtqueue_detach_unused_buf_split(struct virtqueue *_vq) +{ + struct vring_virtqueue *vq = to_vvq(_vq); + unsigned int i; + void *buf; + + START_USE(vq); + + for (i = 0; i < vq->split.vring.num; i++) { + if (!vq->split.desc_state[i].data) + continue; + /* detach_buf_split clears data, so grab it now. */ + buf = vq->split.desc_state[i].data; + detach_buf_split(vq, i, NULL); + vq->split.avail_idx_shadow--; + vq->split.vring.avail->idx = cpu_to_virtio16(_vq->vdev, + vq->split.avail_idx_shadow); + END_USE(vq); + return buf; + } + /* That should have freed everything. */ + BUG_ON(vq->vq.num_free != vq->split.vring.num); + + END_USE(vq); + return NULL; +} + +static void virtqueue_vring_init_split(struct vring_virtqueue_split *vring_split, + struct vring_virtqueue *vq) +{ + struct virtio_device *vdev; + + vdev = vq->vq.vdev; + + vring_split->avail_flags_shadow = 0; + vring_split->avail_idx_shadow = 0; + + /* No callback? Tell other side not to bother us. */ + if (!vq->vq.callback) { + vring_split->avail_flags_shadow |= VRING_AVAIL_F_NO_INTERRUPT; + if (!vq->event) + vring_split->vring.avail->flags = cpu_to_virtio16(vdev, + vring_split->avail_flags_shadow); + } +} + +static void virtqueue_reinit_split(struct vring_virtqueue *vq) +{ + int num; + + num = vq->split.vring.num; + + vq->split.vring.avail->flags = 0; + vq->split.vring.avail->idx = 0; + + /* reset avail event */ + vq->split.vring.avail->ring[num] = 0; + + vq->split.vring.used->flags = 0; + vq->split.vring.used->idx = 0; + + /* reset used event */ + *(__virtio16 *)&(vq->split.vring.used->ring[num]) = 0; + + virtqueue_init(vq, num); + + virtqueue_vring_init_split(&vq->split, vq); +} + +static void virtqueue_vring_attach_split(struct vring_virtqueue *vq, + struct vring_virtqueue_split *vring_split) +{ + vq->split = *vring_split; + + /* Put everything in free lists. */ + vq->free_head = 0; +} + +static int vring_alloc_state_extra_split(struct vring_virtqueue_split *vring_split) +{ + struct vring_desc_state_split *state; + struct vring_desc_extra *extra; + u32 num = vring_split->vring.num; + + state = kmalloc_array(num, sizeof(struct vring_desc_state_split), GFP_KERNEL); + if (!state) + goto err_state; + + extra = vring_alloc_desc_extra(num); + if (!extra) + goto err_extra; + + memset(state, 0, num * sizeof(struct vring_desc_state_split)); + + vring_split->desc_state = state; + vring_split->desc_extra = extra; + return 0; + +err_extra: + kfree(state); +err_state: + return -ENOMEM; +} + +static void vring_free_split(struct vring_virtqueue_split *vring_split, + struct virtio_device *vdev, + union virtio_map map) +{ + vring_free_queue(vdev, vring_split->queue_size_in_bytes, + vring_split->vring.desc, + vring_split->queue_dma_addr, + map); + + kfree(vring_split->desc_state); + kfree(vring_split->desc_extra); +} + +static int vring_alloc_queue_split(struct vring_virtqueue_split *vring_split, + struct virtio_device *vdev, + u32 num, + unsigned int vring_align, + bool may_reduce_num, + union virtio_map map) +{ + void *queue = NULL; + dma_addr_t dma_addr; + + /* We assume num is a power of 2. */ + if (!is_power_of_2(num)) { + dev_warn(&vdev->dev, "Bad virtqueue length %u\n", num); + return -EINVAL; + } + + /* TODO: allocate each queue chunk individually */ + for (; num && vring_size(num, vring_align) > PAGE_SIZE; num /= 2) { + queue = vring_alloc_queue(vdev, vring_size(num, vring_align), + &dma_addr, + GFP_KERNEL | __GFP_NOWARN | __GFP_ZERO, + map); + if (queue) + break; + if (!may_reduce_num) + return -ENOMEM; + } + + if (!num) + return -ENOMEM; + + if (!queue) { + /* Try to get a single page. You are my only hope! */ + queue = vring_alloc_queue(vdev, vring_size(num, vring_align), + &dma_addr, GFP_KERNEL | __GFP_ZERO, + map); + } + if (!queue) + return -ENOMEM; + + vring_init(&vring_split->vring, num, queue, vring_align); + + vring_split->queue_dma_addr = dma_addr; + vring_split->queue_size_in_bytes = vring_size(num, vring_align); + + vring_split->vring_align = vring_align; + vring_split->may_reduce_num = may_reduce_num; + + return 0; +} + +static struct virtqueue *__vring_new_virtqueue_split(unsigned int index, + struct vring_virtqueue_split *vring_split, + struct virtio_device *vdev, + bool weak_barriers, + bool context, + bool (*notify)(struct virtqueue *), + void (*callback)(struct virtqueue *), + const char *name, + union virtio_map map) +{ + struct vring_virtqueue *vq; + int err; + + vq = kmalloc(sizeof(*vq), GFP_KERNEL); + if (!vq) + return NULL; + + vq->packed_ring = false; + vq->vq.callback = callback; + vq->vq.vdev = vdev; + vq->vq.name = name; + vq->vq.index = index; + vq->vq.reset = false; + vq->we_own_ring = false; + vq->notify = notify; + vq->weak_barriers = weak_barriers; +#ifdef CONFIG_VIRTIO_HARDEN_NOTIFICATION + vq->broken = true; +#else + vq->broken = false; +#endif + vq->map = map; + vq->use_map_api = vring_use_map_api(vdev); + + vq->indirect = virtio_has_feature(vdev, VIRTIO_RING_F_INDIRECT_DESC) && + !context; + vq->event = virtio_has_feature(vdev, VIRTIO_RING_F_EVENT_IDX); + + if (virtio_has_feature(vdev, VIRTIO_F_ORDER_PLATFORM)) + vq->weak_barriers = false; + + err = vring_alloc_state_extra_split(vring_split); + if (err) { + kfree(vq); + return NULL; + } + + virtqueue_vring_init_split(vring_split, vq); + + virtqueue_init(vq, vring_split->vring.num); + virtqueue_vring_attach_split(vq, vring_split); + + spin_lock(&vdev->vqs_list_lock); + list_add_tail(&vq->vq.list, &vdev->vqs); + spin_unlock(&vdev->vqs_list_lock); + return &vq->vq; +} + +static struct virtqueue *vring_create_virtqueue_split( + unsigned int index, + unsigned int num, + unsigned int vring_align, + struct virtio_device *vdev, + bool weak_barriers, + bool may_reduce_num, + bool context, + bool (*notify)(struct virtqueue *), + void (*callback)(struct virtqueue *), + const char *name, + union virtio_map map) +{ + struct vring_virtqueue_split vring_split = {}; + struct virtqueue *vq; + int err; + + err = vring_alloc_queue_split(&vring_split, vdev, num, vring_align, + may_reduce_num, map); + if (err) + return NULL; + + vq = __vring_new_virtqueue_split(index, &vring_split, vdev, weak_barriers, + context, notify, callback, name, map); + if (!vq) { + vring_free_split(&vring_split, vdev, map); + return NULL; + } + + to_vvq(vq)->we_own_ring = true; + + return vq; +} + +static int virtqueue_resize_split(struct virtqueue *_vq, u32 num) +{ + struct vring_virtqueue_split vring_split = {}; + struct vring_virtqueue *vq = to_vvq(_vq); + struct virtio_device *vdev = _vq->vdev; + int err; + + err = vring_alloc_queue_split(&vring_split, vdev, num, + vq->split.vring_align, + vq->split.may_reduce_num, + vq->map); + if (err) + goto err; + + err = vring_alloc_state_extra_split(&vring_split); + if (err) + goto err_state_extra; + + vring_free(&vq->vq); + + virtqueue_vring_init_split(&vring_split, vq); + + virtqueue_init(vq, vring_split.vring.num); + virtqueue_vring_attach_split(vq, &vring_split); + + return 0; + +err_state_extra: + vring_free_split(&vring_split, vdev, vq->map); +err: + virtqueue_reinit_split(vq); + return -ENOMEM; +} + + +/* + * Packed ring specific functions - *_packed(). + */ +static bool packed_used_wrap_counter(u16 last_used_idx) +{ + return !!(last_used_idx & (1 << VRING_PACKED_EVENT_F_WRAP_CTR)); +} + +static u16 packed_last_used(u16 last_used_idx) +{ + return last_used_idx & ~(-(1 << VRING_PACKED_EVENT_F_WRAP_CTR)); +} + +static void vring_unmap_extra_packed(const struct vring_virtqueue *vq, + const struct vring_desc_extra *extra) +{ + u16 flags; + + flags = extra->flags; + + if (flags & VRING_DESC_F_INDIRECT) { + if (!vq->use_map_api) + return; + } else if (!vring_need_unmap_buffer(vq, extra)) + return; + + virtqueue_unmap_page_attrs(&vq->vq, + extra->addr, extra->len, + (flags & VRING_DESC_F_WRITE) ? + DMA_FROM_DEVICE : DMA_TO_DEVICE, + 0); +} + +static struct vring_packed_desc *alloc_indirect_packed(unsigned int total_sg, + gfp_t gfp) +{ + struct vring_desc_extra *extra; + struct vring_packed_desc *desc; + int i, size; + + /* + * We require lowmem mappings for the descriptors because + * otherwise virt_to_phys will give us bogus addresses in the + * virtqueue. + */ + gfp &= ~__GFP_HIGHMEM; + + size = (sizeof(*desc) + sizeof(*extra)) * total_sg; + + desc = kmalloc(size, gfp); + if (!desc) + return NULL; + + extra = (struct vring_desc_extra *)&desc[total_sg]; + + for (i = 0; i < total_sg; i++) + extra[i].next = i + 1; + + return desc; +} + +static int virtqueue_add_indirect_packed(struct vring_virtqueue *vq, + struct scatterlist *sgs[], + unsigned int total_sg, + unsigned int out_sgs, + unsigned int in_sgs, + void *data, + bool premapped, + gfp_t gfp) +{ + struct vring_desc_extra *extra; + struct vring_packed_desc *desc; + struct scatterlist *sg; + unsigned int i, n, err_idx, len; + u16 head, id; + dma_addr_t addr; + + head = vq->packed.next_avail_idx; + desc = alloc_indirect_packed(total_sg, gfp); + if (!desc) + return -ENOMEM; + + extra = (struct vring_desc_extra *)&desc[total_sg]; + + if (unlikely(vq->vq.num_free < 1)) { + pr_debug("Can't add buf len 1 - avail = 0\n"); + kfree(desc); + END_USE(vq); + return -ENOSPC; + } + + i = 0; + id = vq->free_head; + BUG_ON(id == vq->packed.vring.num); + + for (n = 0; n < out_sgs + in_sgs; n++) { + for (sg = sgs[n]; sg; sg = sg_next(sg)) { + if (vring_map_one_sg(vq, sg, n < out_sgs ? + DMA_TO_DEVICE : DMA_FROM_DEVICE, + &addr, &len, premapped)) + goto unmap_release; + + desc[i].flags = cpu_to_le16(n < out_sgs ? + 0 : VRING_DESC_F_WRITE); + desc[i].addr = cpu_to_le64(addr); + desc[i].len = cpu_to_le32(len); + + if (unlikely(vq->use_map_api)) { + extra[i].addr = premapped ? DMA_MAPPING_ERROR : addr; + extra[i].len = len; + extra[i].flags = n < out_sgs ? 0 : VRING_DESC_F_WRITE; + } + + i++; + } + } + + /* Now that the indirect table is filled in, map it. */ + addr = vring_map_single(vq, desc, + total_sg * sizeof(struct vring_packed_desc), + DMA_TO_DEVICE); + if (vring_mapping_error(vq, addr)) + goto unmap_release; + + vq->packed.vring.desc[head].addr = cpu_to_le64(addr); + vq->packed.vring.desc[head].len = cpu_to_le32(total_sg * + sizeof(struct vring_packed_desc)); + vq->packed.vring.desc[head].id = cpu_to_le16(id); + + if (vq->use_map_api) { + vq->packed.desc_extra[id].addr = addr; + vq->packed.desc_extra[id].len = total_sg * + sizeof(struct vring_packed_desc); + vq->packed.desc_extra[id].flags = VRING_DESC_F_INDIRECT | + vq->packed.avail_used_flags; + } + + /* + * A driver MUST NOT make the first descriptor in the list + * available before all subsequent descriptors comprising + * the list are made available. + */ + virtio_wmb(vq->weak_barriers); + vq->packed.vring.desc[head].flags = cpu_to_le16(VRING_DESC_F_INDIRECT | + vq->packed.avail_used_flags); + + /* We're using some buffers from the free list. */ + vq->vq.num_free -= 1; + + /* Update free pointer */ + n = head + 1; + if (n >= vq->packed.vring.num) { + n = 0; + vq->packed.avail_wrap_counter ^= 1; + vq->packed.avail_used_flags ^= + 1 << VRING_PACKED_DESC_F_AVAIL | + 1 << VRING_PACKED_DESC_F_USED; + } + vq->packed.next_avail_idx = n; + vq->free_head = vq->packed.desc_extra[id].next; + + /* Store token and indirect buffer state. */ + vq->packed.desc_state[id].num = 1; + vq->packed.desc_state[id].data = data; + vq->packed.desc_state[id].indir_desc = desc; + vq->packed.desc_state[id].last = id; + + vq->num_added += 1; + pr_debug("Added buffer head %i to %p\n", head, vq); END_USE(vq); return 0; + +unmap_release: + err_idx = i; + + for (i = 0; i < err_idx; i++) + vring_unmap_extra_packed(vq, &extra[i]); + + kfree(desc); + + END_USE(vq); + return -ENOMEM; +} + +static inline int virtqueue_add_packed(struct virtqueue *_vq, + struct scatterlist *sgs[], + unsigned int total_sg, + unsigned int out_sgs, + unsigned int in_sgs, + void *data, + void *ctx, + bool premapped, + gfp_t gfp) +{ + struct vring_virtqueue *vq = to_vvq(_vq); + struct vring_packed_desc *desc; + struct scatterlist *sg; + unsigned int i, n, c, descs_used, err_idx, len; + __le16 head_flags, flags; + u16 head, id, prev, curr, avail_used_flags; + int err; + + START_USE(vq); + + BUG_ON(data == NULL); + BUG_ON(ctx && vq->indirect); + + if (unlikely(vq->broken)) { + END_USE(vq); + return -EIO; + } + + LAST_ADD_TIME_UPDATE(vq); + + BUG_ON(total_sg == 0); + + if (virtqueue_use_indirect(vq, total_sg)) { + err = virtqueue_add_indirect_packed(vq, sgs, total_sg, out_sgs, + in_sgs, data, premapped, gfp); + if (err != -ENOMEM) { + END_USE(vq); + return err; + } + + /* fall back on direct */ + } + + head = vq->packed.next_avail_idx; + avail_used_flags = vq->packed.avail_used_flags; + + WARN_ON_ONCE(total_sg > vq->packed.vring.num && !vq->indirect); + + desc = vq->packed.vring.desc; + i = head; + descs_used = total_sg; + + if (unlikely(vq->vq.num_free < descs_used)) { + pr_debug("Can't add buf len %i - avail = %i\n", + descs_used, vq->vq.num_free); + END_USE(vq); + return -ENOSPC; + } + + id = vq->free_head; + BUG_ON(id == vq->packed.vring.num); + + curr = id; + c = 0; + for (n = 0; n < out_sgs + in_sgs; n++) { + for (sg = sgs[n]; sg; sg = sg_next(sg)) { + dma_addr_t addr; + + if (vring_map_one_sg(vq, sg, n < out_sgs ? + DMA_TO_DEVICE : DMA_FROM_DEVICE, + &addr, &len, premapped)) + goto unmap_release; + + flags = cpu_to_le16(vq->packed.avail_used_flags | + (++c == total_sg ? 0 : VRING_DESC_F_NEXT) | + (n < out_sgs ? 0 : VRING_DESC_F_WRITE)); + if (i == head) + head_flags = flags; + else + desc[i].flags = flags; + + desc[i].addr = cpu_to_le64(addr); + desc[i].len = cpu_to_le32(len); + desc[i].id = cpu_to_le16(id); + + if (unlikely(vq->use_map_api)) { + vq->packed.desc_extra[curr].addr = premapped ? + DMA_MAPPING_ERROR : addr; + vq->packed.desc_extra[curr].len = len; + vq->packed.desc_extra[curr].flags = + le16_to_cpu(flags); + } + prev = curr; + curr = vq->packed.desc_extra[curr].next; + + if ((unlikely(++i >= vq->packed.vring.num))) { + i = 0; + vq->packed.avail_used_flags ^= + 1 << VRING_PACKED_DESC_F_AVAIL | + 1 << VRING_PACKED_DESC_F_USED; + } + } + } + + if (i <= head) + vq->packed.avail_wrap_counter ^= 1; + + /* We're using some buffers from the free list. */ + vq->vq.num_free -= descs_used; + + /* Update free pointer */ + vq->packed.next_avail_idx = i; + vq->free_head = curr; + + /* Store token. */ + vq->packed.desc_state[id].num = descs_used; + vq->packed.desc_state[id].data = data; + vq->packed.desc_state[id].indir_desc = ctx; + vq->packed.desc_state[id].last = prev; + + /* + * A driver MUST NOT make the first descriptor in the list + * available before all subsequent descriptors comprising + * the list are made available. + */ + virtio_wmb(vq->weak_barriers); + vq->packed.vring.desc[head].flags = head_flags; + vq->num_added += descs_used; + + pr_debug("Added buffer head %i to %p\n", head, vq); + END_USE(vq); + + return 0; + +unmap_release: + err_idx = i; + i = head; + curr = vq->free_head; + + vq->packed.avail_used_flags = avail_used_flags; + + for (n = 0; n < total_sg; n++) { + if (i == err_idx) + break; + vring_unmap_extra_packed(vq, &vq->packed.desc_extra[curr]); + curr = vq->packed.desc_extra[curr].next; + i++; + if (i >= vq->packed.vring.num) + i = 0; + } + + END_USE(vq); + return -EIO; +} + +static bool virtqueue_kick_prepare_packed(struct virtqueue *_vq) +{ + struct vring_virtqueue *vq = to_vvq(_vq); + u16 new, old, off_wrap, flags, wrap_counter, event_idx; + bool needs_kick; + union { + struct { + __le16 off_wrap; + __le16 flags; + }; + u32 u32; + } snapshot; + + START_USE(vq); + + /* + * We need to expose the new flags value before checking notification + * suppressions. + */ + virtio_mb(vq->weak_barriers); + + old = vq->packed.next_avail_idx - vq->num_added; + new = vq->packed.next_avail_idx; + vq->num_added = 0; + + snapshot.u32 = *(u32 *)vq->packed.vring.device; + flags = le16_to_cpu(snapshot.flags); + + LAST_ADD_TIME_CHECK(vq); + LAST_ADD_TIME_INVALID(vq); + + if (flags != VRING_PACKED_EVENT_FLAG_DESC) { + needs_kick = (flags != VRING_PACKED_EVENT_FLAG_DISABLE); + goto out; + } + + off_wrap = le16_to_cpu(snapshot.off_wrap); + + wrap_counter = off_wrap >> VRING_PACKED_EVENT_F_WRAP_CTR; + event_idx = off_wrap & ~(1 << VRING_PACKED_EVENT_F_WRAP_CTR); + if (wrap_counter != vq->packed.avail_wrap_counter) + event_idx -= vq->packed.vring.num; + + needs_kick = vring_need_event(event_idx, new, old); +out: + END_USE(vq); + return needs_kick; +} + +static void detach_buf_packed(struct vring_virtqueue *vq, + unsigned int id, void **ctx) +{ + struct vring_desc_state_packed *state = NULL; + struct vring_packed_desc *desc; + unsigned int i, curr; + + state = &vq->packed.desc_state[id]; + + /* Clear data ptr. */ + state->data = NULL; + + vq->packed.desc_extra[state->last].next = vq->free_head; + vq->free_head = id; + vq->vq.num_free += state->num; + + if (unlikely(vq->use_map_api)) { + curr = id; + for (i = 0; i < state->num; i++) { + vring_unmap_extra_packed(vq, + &vq->packed.desc_extra[curr]); + curr = vq->packed.desc_extra[curr].next; + } + } + + if (vq->indirect) { + struct vring_desc_extra *extra; + u32 len, num; + + /* Free the indirect table, if any, now that it's unmapped. */ + desc = state->indir_desc; + if (!desc) + return; + + if (vq->use_map_api) { + len = vq->packed.desc_extra[id].len; + num = len / sizeof(struct vring_packed_desc); + + extra = (struct vring_desc_extra *)&desc[num]; + + for (i = 0; i < num; i++) + vring_unmap_extra_packed(vq, &extra[i]); + } + kfree(desc); + state->indir_desc = NULL; + } else if (ctx) { + *ctx = state->indir_desc; + } +} + +static inline bool is_used_desc_packed(const struct vring_virtqueue *vq, + u16 idx, bool used_wrap_counter) +{ + bool avail, used; + u16 flags; + + flags = le16_to_cpu(vq->packed.vring.desc[idx].flags); + avail = !!(flags & (1 << VRING_PACKED_DESC_F_AVAIL)); + used = !!(flags & (1 << VRING_PACKED_DESC_F_USED)); + + return avail == used && used == used_wrap_counter; +} + +static bool more_used_packed(const struct vring_virtqueue *vq) +{ + u16 last_used; + u16 last_used_idx; + bool used_wrap_counter; + + last_used_idx = READ_ONCE(vq->last_used_idx); + last_used = packed_last_used(last_used_idx); + used_wrap_counter = packed_used_wrap_counter(last_used_idx); + return is_used_desc_packed(vq, last_used, used_wrap_counter); +} + +static void *virtqueue_get_buf_ctx_packed(struct virtqueue *_vq, + unsigned int *len, + void **ctx) +{ + struct vring_virtqueue *vq = to_vvq(_vq); + u16 last_used, id, last_used_idx; + bool used_wrap_counter; + void *ret; + + START_USE(vq); + + if (unlikely(vq->broken)) { + END_USE(vq); + return NULL; + } + + if (!more_used_packed(vq)) { + pr_debug("No more buffers in queue\n"); + END_USE(vq); + return NULL; + } + + /* Only get used elements after they have been exposed by host. */ + virtio_rmb(vq->weak_barriers); + + last_used_idx = READ_ONCE(vq->last_used_idx); + used_wrap_counter = packed_used_wrap_counter(last_used_idx); + last_used = packed_last_used(last_used_idx); + id = le16_to_cpu(vq->packed.vring.desc[last_used].id); + *len = le32_to_cpu(vq->packed.vring.desc[last_used].len); + + if (unlikely(id >= vq->packed.vring.num)) { + BAD_RING(vq, "id %u out of range\n", id); + return NULL; + } + if (unlikely(!vq->packed.desc_state[id].data)) { + BAD_RING(vq, "id %u is not a head!\n", id); + return NULL; + } + + /* detach_buf_packed clears data, so grab it now. */ + ret = vq->packed.desc_state[id].data; + detach_buf_packed(vq, id, ctx); + + last_used += vq->packed.desc_state[id].num; + if (unlikely(last_used >= vq->packed.vring.num)) { + last_used -= vq->packed.vring.num; + used_wrap_counter ^= 1; + } + + last_used = (last_used | (used_wrap_counter << VRING_PACKED_EVENT_F_WRAP_CTR)); + WRITE_ONCE(vq->last_used_idx, last_used); + + /* + * If we expect an interrupt for the next entry, tell host + * by writing event index and flush out the write before + * the read in the next get_buf call. + */ + if (vq->packed.event_flags_shadow == VRING_PACKED_EVENT_FLAG_DESC) + virtio_store_mb(vq->weak_barriers, + &vq->packed.vring.driver->off_wrap, + cpu_to_le16(vq->last_used_idx)); + + LAST_ADD_TIME_INVALID(vq); + + END_USE(vq); + return ret; +} + +static void virtqueue_disable_cb_packed(struct virtqueue *_vq) +{ + struct vring_virtqueue *vq = to_vvq(_vq); + + if (vq->packed.event_flags_shadow != VRING_PACKED_EVENT_FLAG_DISABLE) { + vq->packed.event_flags_shadow = VRING_PACKED_EVENT_FLAG_DISABLE; + + /* + * If device triggered an event already it won't trigger one again: + * no need to disable. + */ + if (vq->event_triggered) + return; + + vq->packed.vring.driver->flags = + cpu_to_le16(vq->packed.event_flags_shadow); + } +} + +static unsigned int virtqueue_enable_cb_prepare_packed(struct virtqueue *_vq) +{ + struct vring_virtqueue *vq = to_vvq(_vq); + + START_USE(vq); + + /* + * We optimistically turn back on interrupts, then check if there was + * more to do. + */ + + if (vq->event) { + vq->packed.vring.driver->off_wrap = + cpu_to_le16(vq->last_used_idx); + /* + * We need to update event offset and event wrap + * counter first before updating event flags. + */ + virtio_wmb(vq->weak_barriers); + } + + if (vq->packed.event_flags_shadow == VRING_PACKED_EVENT_FLAG_DISABLE) { + vq->packed.event_flags_shadow = vq->event ? + VRING_PACKED_EVENT_FLAG_DESC : + VRING_PACKED_EVENT_FLAG_ENABLE; + vq->packed.vring.driver->flags = + cpu_to_le16(vq->packed.event_flags_shadow); + } + + END_USE(vq); + return vq->last_used_idx; +} + +static bool virtqueue_poll_packed(struct virtqueue *_vq, u16 off_wrap) +{ + struct vring_virtqueue *vq = to_vvq(_vq); + bool wrap_counter; + u16 used_idx; + + wrap_counter = off_wrap >> VRING_PACKED_EVENT_F_WRAP_CTR; + used_idx = off_wrap & ~(1 << VRING_PACKED_EVENT_F_WRAP_CTR); + + return is_used_desc_packed(vq, used_idx, wrap_counter); +} + +static bool virtqueue_enable_cb_delayed_packed(struct virtqueue *_vq) +{ + struct vring_virtqueue *vq = to_vvq(_vq); + u16 used_idx, wrap_counter, last_used_idx; + u16 bufs; + + START_USE(vq); + + /* + * We optimistically turn back on interrupts, then check if there was + * more to do. + */ + + if (vq->event) { + /* TODO: tune this threshold */ + bufs = (vq->packed.vring.num - vq->vq.num_free) * 3 / 4; + last_used_idx = READ_ONCE(vq->last_used_idx); + wrap_counter = packed_used_wrap_counter(last_used_idx); + + used_idx = packed_last_used(last_used_idx) + bufs; + if (used_idx >= vq->packed.vring.num) { + used_idx -= vq->packed.vring.num; + wrap_counter ^= 1; + } + + vq->packed.vring.driver->off_wrap = cpu_to_le16(used_idx | + (wrap_counter << VRING_PACKED_EVENT_F_WRAP_CTR)); + + /* + * We need to update event offset and event wrap + * counter first before updating event flags. + */ + virtio_wmb(vq->weak_barriers); + } + + if (vq->packed.event_flags_shadow == VRING_PACKED_EVENT_FLAG_DISABLE) { + vq->packed.event_flags_shadow = vq->event ? + VRING_PACKED_EVENT_FLAG_DESC : + VRING_PACKED_EVENT_FLAG_ENABLE; + vq->packed.vring.driver->flags = + cpu_to_le16(vq->packed.event_flags_shadow); + } + + /* + * We need to update event suppression structure first + * before re-checking for more used buffers. + */ + virtio_mb(vq->weak_barriers); + + last_used_idx = READ_ONCE(vq->last_used_idx); + wrap_counter = packed_used_wrap_counter(last_used_idx); + used_idx = packed_last_used(last_used_idx); + if (is_used_desc_packed(vq, used_idx, wrap_counter)) { + END_USE(vq); + return false; + } + + END_USE(vq); + return true; +} + +static void *virtqueue_detach_unused_buf_packed(struct virtqueue *_vq) +{ + struct vring_virtqueue *vq = to_vvq(_vq); + unsigned int i; + void *buf; + + START_USE(vq); + + for (i = 0; i < vq->packed.vring.num; i++) { + if (!vq->packed.desc_state[i].data) + continue; + /* detach_buf clears data, so grab it now. */ + buf = vq->packed.desc_state[i].data; + detach_buf_packed(vq, i, NULL); + END_USE(vq); + return buf; + } + /* That should have freed everything. */ + BUG_ON(vq->vq.num_free != vq->packed.vring.num); + + END_USE(vq); + return NULL; +} + +static struct vring_desc_extra *vring_alloc_desc_extra(unsigned int num) +{ + struct vring_desc_extra *desc_extra; + unsigned int i; + + desc_extra = kmalloc_array(num, sizeof(struct vring_desc_extra), + GFP_KERNEL); + if (!desc_extra) + return NULL; + + memset(desc_extra, 0, num * sizeof(struct vring_desc_extra)); + + for (i = 0; i < num - 1; i++) + desc_extra[i].next = i + 1; + + return desc_extra; +} + +static void vring_free_packed(struct vring_virtqueue_packed *vring_packed, + struct virtio_device *vdev, + union virtio_map map) +{ + if (vring_packed->vring.desc) + vring_free_queue(vdev, vring_packed->ring_size_in_bytes, + vring_packed->vring.desc, + vring_packed->ring_dma_addr, + map); + + if (vring_packed->vring.driver) + vring_free_queue(vdev, vring_packed->event_size_in_bytes, + vring_packed->vring.driver, + vring_packed->driver_event_dma_addr, + map); + + if (vring_packed->vring.device) + vring_free_queue(vdev, vring_packed->event_size_in_bytes, + vring_packed->vring.device, + vring_packed->device_event_dma_addr, + map); + + kfree(vring_packed->desc_state); + kfree(vring_packed->desc_extra); +} + +static int vring_alloc_queue_packed(struct vring_virtqueue_packed *vring_packed, + struct virtio_device *vdev, + u32 num, union virtio_map map) +{ + struct vring_packed_desc *ring; + struct vring_packed_desc_event *driver, *device; + dma_addr_t ring_dma_addr, driver_event_dma_addr, device_event_dma_addr; + size_t ring_size_in_bytes, event_size_in_bytes; + + ring_size_in_bytes = num * sizeof(struct vring_packed_desc); + + ring = vring_alloc_queue(vdev, ring_size_in_bytes, + &ring_dma_addr, + GFP_KERNEL | __GFP_NOWARN | __GFP_ZERO, + map); + if (!ring) + goto err; + + vring_packed->vring.desc = ring; + vring_packed->ring_dma_addr = ring_dma_addr; + vring_packed->ring_size_in_bytes = ring_size_in_bytes; + + event_size_in_bytes = sizeof(struct vring_packed_desc_event); + + driver = vring_alloc_queue(vdev, event_size_in_bytes, + &driver_event_dma_addr, + GFP_KERNEL | __GFP_NOWARN | __GFP_ZERO, + map); + if (!driver) + goto err; + + vring_packed->vring.driver = driver; + vring_packed->event_size_in_bytes = event_size_in_bytes; + vring_packed->driver_event_dma_addr = driver_event_dma_addr; + + device = vring_alloc_queue(vdev, event_size_in_bytes, + &device_event_dma_addr, + GFP_KERNEL | __GFP_NOWARN | __GFP_ZERO, + map); + if (!device) + goto err; + + vring_packed->vring.device = device; + vring_packed->device_event_dma_addr = device_event_dma_addr; + + vring_packed->vring.num = num; + + return 0; + +err: + vring_free_packed(vring_packed, vdev, map); + return -ENOMEM; +} + +static int vring_alloc_state_extra_packed(struct vring_virtqueue_packed *vring_packed) +{ + struct vring_desc_state_packed *state; + struct vring_desc_extra *extra; + u32 num = vring_packed->vring.num; + + state = kmalloc_array(num, sizeof(struct vring_desc_state_packed), GFP_KERNEL); + if (!state) + goto err_desc_state; + + memset(state, 0, num * sizeof(struct vring_desc_state_packed)); + + extra = vring_alloc_desc_extra(num); + if (!extra) + goto err_desc_extra; + + vring_packed->desc_state = state; + vring_packed->desc_extra = extra; + + return 0; + +err_desc_extra: + kfree(state); +err_desc_state: + return -ENOMEM; +} + +static void virtqueue_vring_init_packed(struct vring_virtqueue_packed *vring_packed, + bool callback) +{ + vring_packed->next_avail_idx = 0; + vring_packed->avail_wrap_counter = 1; + vring_packed->event_flags_shadow = 0; + vring_packed->avail_used_flags = 1 << VRING_PACKED_DESC_F_AVAIL; + + /* No callback? Tell other side not to bother us. */ + if (!callback) { + vring_packed->event_flags_shadow = VRING_PACKED_EVENT_FLAG_DISABLE; + vring_packed->vring.driver->flags = + cpu_to_le16(vring_packed->event_flags_shadow); + } +} + +static void virtqueue_vring_attach_packed(struct vring_virtqueue *vq, + struct vring_virtqueue_packed *vring_packed) +{ + vq->packed = *vring_packed; + + /* Put everything in free lists. */ + vq->free_head = 0; +} + +static void virtqueue_reinit_packed(struct vring_virtqueue *vq) +{ + memset(vq->packed.vring.device, 0, vq->packed.event_size_in_bytes); + memset(vq->packed.vring.driver, 0, vq->packed.event_size_in_bytes); + + /* we need to reset the desc.flags. For more, see is_used_desc_packed() */ + memset(vq->packed.vring.desc, 0, vq->packed.ring_size_in_bytes); + + virtqueue_init(vq, vq->packed.vring.num); + virtqueue_vring_init_packed(&vq->packed, !!vq->vq.callback); +} + +static struct virtqueue *__vring_new_virtqueue_packed(unsigned int index, + struct vring_virtqueue_packed *vring_packed, + struct virtio_device *vdev, + bool weak_barriers, + bool context, + bool (*notify)(struct virtqueue *), + void (*callback)(struct virtqueue *), + const char *name, + union virtio_map map) +{ + struct vring_virtqueue *vq; + int err; + + vq = kmalloc(sizeof(*vq), GFP_KERNEL); + if (!vq) + return NULL; + + vq->vq.callback = callback; + vq->vq.vdev = vdev; + vq->vq.name = name; + vq->vq.index = index; + vq->vq.reset = false; + vq->we_own_ring = false; + vq->notify = notify; + vq->weak_barriers = weak_barriers; +#ifdef CONFIG_VIRTIO_HARDEN_NOTIFICATION + vq->broken = true; +#else + vq->broken = false; +#endif + vq->packed_ring = true; + vq->map = map; + vq->use_map_api = vring_use_map_api(vdev); + + vq->indirect = virtio_has_feature(vdev, VIRTIO_RING_F_INDIRECT_DESC) && + !context; + vq->event = virtio_has_feature(vdev, VIRTIO_RING_F_EVENT_IDX); + + if (virtio_has_feature(vdev, VIRTIO_F_ORDER_PLATFORM)) + vq->weak_barriers = false; + + err = vring_alloc_state_extra_packed(vring_packed); + if (err) { + kfree(vq); + return NULL; + } + + virtqueue_vring_init_packed(vring_packed, !!callback); + + virtqueue_init(vq, vring_packed->vring.num); + virtqueue_vring_attach_packed(vq, vring_packed); + + spin_lock(&vdev->vqs_list_lock); + list_add_tail(&vq->vq.list, &vdev->vqs); + spin_unlock(&vdev->vqs_list_lock); + return &vq->vq; +} + +static struct virtqueue *vring_create_virtqueue_packed( + unsigned int index, + unsigned int num, + unsigned int vring_align, + struct virtio_device *vdev, + bool weak_barriers, + bool may_reduce_num, + bool context, + bool (*notify)(struct virtqueue *), + void (*callback)(struct virtqueue *), + const char *name, + union virtio_map map) +{ + struct vring_virtqueue_packed vring_packed = {}; + struct virtqueue *vq; + + if (vring_alloc_queue_packed(&vring_packed, vdev, num, map)) + return NULL; + + vq = __vring_new_virtqueue_packed(index, &vring_packed, vdev, weak_barriers, + context, notify, callback, name, map); + if (!vq) { + vring_free_packed(&vring_packed, vdev, map); + return NULL; + } + + to_vvq(vq)->we_own_ring = true; + + return vq; +} + +static int virtqueue_resize_packed(struct virtqueue *_vq, u32 num) +{ + struct vring_virtqueue_packed vring_packed = {}; + struct vring_virtqueue *vq = to_vvq(_vq); + struct virtio_device *vdev = _vq->vdev; + int err; + + if (vring_alloc_queue_packed(&vring_packed, vdev, num, vq->map)) + goto err_ring; + + err = vring_alloc_state_extra_packed(&vring_packed); + if (err) + goto err_state_extra; + + vring_free(&vq->vq); + + virtqueue_vring_init_packed(&vring_packed, !!vq->vq.callback); + + virtqueue_init(vq, vring_packed.vring.num); + virtqueue_vring_attach_packed(vq, &vring_packed); + + return 0; + +err_state_extra: + vring_free_packed(&vring_packed, vdev, vq->map); +err_ring: + virtqueue_reinit_packed(vq); + return -ENOMEM; +} + +static int virtqueue_disable_and_recycle(struct virtqueue *_vq, + void (*recycle)(struct virtqueue *vq, void *buf)) +{ + struct vring_virtqueue *vq = to_vvq(_vq); + struct virtio_device *vdev = vq->vq.vdev; + void *buf; + int err; + + if (!vq->we_own_ring) + return -EPERM; + + if (!vdev->config->disable_vq_and_reset) + return -ENOENT; + + if (!vdev->config->enable_vq_after_reset) + return -ENOENT; + + err = vdev->config->disable_vq_and_reset(_vq); + if (err) + return err; + + while ((buf = virtqueue_detach_unused_buf(_vq)) != NULL) + recycle(_vq, buf); + + return 0; +} + +static int virtqueue_enable_after_reset(struct virtqueue *_vq) +{ + struct vring_virtqueue *vq = to_vvq(_vq); + struct virtio_device *vdev = vq->vq.vdev; + + if (vdev->config->enable_vq_after_reset(_vq)) + return -EBUSY; + + return 0; +} + +/* + * Generic functions and exported symbols. + */ + +static inline int virtqueue_add(struct virtqueue *_vq, + struct scatterlist *sgs[], + unsigned int total_sg, + unsigned int out_sgs, + unsigned int in_sgs, + void *data, + void *ctx, + bool premapped, + gfp_t gfp) +{ + struct vring_virtqueue *vq = to_vvq(_vq); + + return vq->packed_ring ? virtqueue_add_packed(_vq, sgs, total_sg, + out_sgs, in_sgs, data, ctx, premapped, gfp) : + virtqueue_add_split(_vq, sgs, total_sg, + out_sgs, in_sgs, data, ctx, premapped, gfp); } /** * virtqueue_add_sgs - expose buffers to other end - * @vq: the struct virtqueue we're talking about. + * @_vq: the struct virtqueue we're talking about. * @sgs: array of terminated scatterlists. - * @out_num: the number of scatterlists readable by other side - * @in_num: the number of scatterlists which are writable (after readable ones) + * @out_sgs: the number of scatterlists readable by other side + * @in_sgs: the number of scatterlists which are writable (after readable ones) * @data: the token identifying the buffer. * @gfp: how to do memory allocations (if necessary). * * Caller must ensure we don't call this with other virtqueue operations * at the same time (except where noted). * - * Returns zero or a negative error (ie. ENOSPC, ENOMEM). + * Returns zero or a negative error (ie. ENOSPC, ENOMEM, EIO). + * + * NB: ENOSPC is a special code that is only returned on an attempt to add a + * buffer to a full VQ. It indicates that some buffers are outstanding and that + * the operation can be retried after some buffers have been used. */ int virtqueue_add_sgs(struct virtqueue *_vq, struct scatterlist *sgs[], @@ -316,71 +2307,156 @@ int virtqueue_add_sgs(struct virtqueue *_vq, void *data, gfp_t gfp) { - unsigned int i, total_out, total_in; + unsigned int i, total_sg = 0; /* Count them first. */ - for (i = total_out = total_in = 0; i < out_sgs; i++) { - struct scatterlist *sg; - for (sg = sgs[i]; sg; sg = sg_next(sg)) - total_out++; - } - for (; i < out_sgs + in_sgs; i++) { + for (i = 0; i < out_sgs + in_sgs; i++) { struct scatterlist *sg; + for (sg = sgs[i]; sg; sg = sg_next(sg)) - total_in++; + total_sg++; } - return virtqueue_add(_vq, sgs, sg_next_chained, - total_out, total_in, out_sgs, in_sgs, data, gfp); + return virtqueue_add(_vq, sgs, total_sg, out_sgs, in_sgs, + data, NULL, false, gfp); } EXPORT_SYMBOL_GPL(virtqueue_add_sgs); /** * virtqueue_add_outbuf - expose output buffers to other end * @vq: the struct virtqueue we're talking about. - * @sgs: array of scatterlists (need not be terminated!) - * @num: the number of scatterlists readable by other side + * @sg: scatterlist (must be well-formed and terminated!) + * @num: the number of entries in @sg readable by other side * @data: the token identifying the buffer. * @gfp: how to do memory allocations (if necessary). * * Caller must ensure we don't call this with other virtqueue operations * at the same time (except where noted). * - * Returns zero or a negative error (ie. ENOSPC, ENOMEM). + * Returns zero or a negative error (ie. ENOSPC, ENOMEM, EIO). */ int virtqueue_add_outbuf(struct virtqueue *vq, - struct scatterlist sg[], unsigned int num, + struct scatterlist *sg, unsigned int num, void *data, gfp_t gfp) { - return virtqueue_add(vq, &sg, sg_next_arr, num, 0, 1, 0, data, gfp); + return virtqueue_add(vq, &sg, num, 1, 0, data, NULL, false, gfp); } EXPORT_SYMBOL_GPL(virtqueue_add_outbuf); /** + * virtqueue_add_outbuf_premapped - expose output buffers to other end + * @vq: the struct virtqueue we're talking about. + * @sg: scatterlist (must be well-formed and terminated!) + * @num: the number of entries in @sg readable by other side + * @data: the token identifying the buffer. + * @gfp: how to do memory allocations (if necessary). + * + * Caller must ensure we don't call this with other virtqueue operations + * at the same time (except where noted). + * + * Return: + * Returns zero or a negative error (ie. ENOSPC, ENOMEM, EIO). + */ +int virtqueue_add_outbuf_premapped(struct virtqueue *vq, + struct scatterlist *sg, unsigned int num, + void *data, + gfp_t gfp) +{ + return virtqueue_add(vq, &sg, num, 1, 0, data, NULL, true, gfp); +} +EXPORT_SYMBOL_GPL(virtqueue_add_outbuf_premapped); + +/** * virtqueue_add_inbuf - expose input buffers to other end * @vq: the struct virtqueue we're talking about. - * @sgs: array of scatterlists (need not be terminated!) - * @num: the number of scatterlists writable by other side + * @sg: scatterlist (must be well-formed and terminated!) + * @num: the number of entries in @sg writable by other side * @data: the token identifying the buffer. * @gfp: how to do memory allocations (if necessary). * * Caller must ensure we don't call this with other virtqueue operations * at the same time (except where noted). * - * Returns zero or a negative error (ie. ENOSPC, ENOMEM). + * Returns zero or a negative error (ie. ENOSPC, ENOMEM, EIO). */ int virtqueue_add_inbuf(struct virtqueue *vq, - struct scatterlist sg[], unsigned int num, + struct scatterlist *sg, unsigned int num, void *data, gfp_t gfp) { - return virtqueue_add(vq, &sg, sg_next_arr, 0, num, 0, 1, data, gfp); + return virtqueue_add(vq, &sg, num, 0, 1, data, NULL, false, gfp); } EXPORT_SYMBOL_GPL(virtqueue_add_inbuf); /** + * virtqueue_add_inbuf_ctx - expose input buffers to other end + * @vq: the struct virtqueue we're talking about. + * @sg: scatterlist (must be well-formed and terminated!) + * @num: the number of entries in @sg writable by other side + * @data: the token identifying the buffer. + * @ctx: extra context for the token + * @gfp: how to do memory allocations (if necessary). + * + * Caller must ensure we don't call this with other virtqueue operations + * at the same time (except where noted). + * + * Returns zero or a negative error (ie. ENOSPC, ENOMEM, EIO). + */ +int virtqueue_add_inbuf_ctx(struct virtqueue *vq, + struct scatterlist *sg, unsigned int num, + void *data, + void *ctx, + gfp_t gfp) +{ + return virtqueue_add(vq, &sg, num, 0, 1, data, ctx, false, gfp); +} +EXPORT_SYMBOL_GPL(virtqueue_add_inbuf_ctx); + +/** + * virtqueue_add_inbuf_premapped - expose input buffers to other end + * @vq: the struct virtqueue we're talking about. + * @sg: scatterlist (must be well-formed and terminated!) + * @num: the number of entries in @sg writable by other side + * @data: the token identifying the buffer. + * @ctx: extra context for the token + * @gfp: how to do memory allocations (if necessary). + * + * Caller must ensure we don't call this with other virtqueue operations + * at the same time (except where noted). + * + * Return: + * Returns zero or a negative error (ie. ENOSPC, ENOMEM, EIO). + */ +int virtqueue_add_inbuf_premapped(struct virtqueue *vq, + struct scatterlist *sg, unsigned int num, + void *data, + void *ctx, + gfp_t gfp) +{ + return virtqueue_add(vq, &sg, num, 0, 1, data, ctx, true, gfp); +} +EXPORT_SYMBOL_GPL(virtqueue_add_inbuf_premapped); + +/** + * virtqueue_dma_dev - get the dma dev + * @_vq: the struct virtqueue we're talking about. + * + * Returns the dma dev. That can been used for dma api. + */ +struct device *virtqueue_dma_dev(struct virtqueue *_vq) +{ + struct vring_virtqueue *vq = to_vvq(_vq); + + if (vq->use_map_api && !_vq->vdev->map) + return vq->map.dma_dev; + else + return NULL; +} +EXPORT_SYMBOL_GPL(virtqueue_dma_dev); + +/** * virtqueue_kick_prepare - first half of split virtqueue_kick call. - * @vq: the struct virtqueue + * @_vq: the struct virtqueue * * Instead of virtqueue_kick(), you can do: * if (virtqueue_kick_prepare(vq)) @@ -392,49 +2468,33 @@ EXPORT_SYMBOL_GPL(virtqueue_add_inbuf); bool virtqueue_kick_prepare(struct virtqueue *_vq) { struct vring_virtqueue *vq = to_vvq(_vq); - u16 new, old; - bool needs_kick; - - START_USE(vq); - /* We need to expose available array entries before checking avail - * event. */ - virtio_mb(vq->weak_barriers); - old = vq->vring.avail->idx - vq->num_added; - new = vq->vring.avail->idx; - vq->num_added = 0; - -#ifdef DEBUG - if (vq->last_add_time_valid) { - WARN_ON(ktime_to_ms(ktime_sub(ktime_get(), - vq->last_add_time)) > 100); - } - vq->last_add_time_valid = false; -#endif - - if (vq->event) { - needs_kick = vring_need_event(vring_avail_event(&vq->vring), - new, old); - } else { - needs_kick = !(vq->vring.used->flags & VRING_USED_F_NO_NOTIFY); - } - END_USE(vq); - return needs_kick; + return vq->packed_ring ? virtqueue_kick_prepare_packed(_vq) : + virtqueue_kick_prepare_split(_vq); } EXPORT_SYMBOL_GPL(virtqueue_kick_prepare); /** * virtqueue_notify - second half of split virtqueue_kick call. - * @vq: the struct virtqueue + * @_vq: the struct virtqueue * * This does not need to be serialized. + * + * Returns false if host notify failed or queue is broken, otherwise true. */ -void virtqueue_notify(struct virtqueue *_vq) +bool virtqueue_notify(struct virtqueue *_vq) { struct vring_virtqueue *vq = to_vvq(_vq); + if (unlikely(vq->broken)) + return false; + /* Prod other side to tell it about changes. */ - vq->notify(_vq); + if (!vq->notify(_vq)) { + vq->broken = true; + return false; + } + return true; } EXPORT_SYMBOL_GPL(virtqueue_notify); @@ -447,50 +2507,24 @@ EXPORT_SYMBOL_GPL(virtqueue_notify); * * Caller must ensure we don't call this with other virtqueue * operations at the same time (except where noted). + * + * Returns false if kick failed, otherwise true. */ -void virtqueue_kick(struct virtqueue *vq) +bool virtqueue_kick(struct virtqueue *vq) { if (virtqueue_kick_prepare(vq)) - virtqueue_notify(vq); + return virtqueue_notify(vq); + return true; } EXPORT_SYMBOL_GPL(virtqueue_kick); -static void detach_buf(struct vring_virtqueue *vq, unsigned int head) -{ - unsigned int i; - - /* Clear data ptr. */ - vq->data[head] = NULL; - - /* Put back on free list: find end */ - i = head; - - /* Free the indirect table */ - if (vq->vring.desc[i].flags & VRING_DESC_F_INDIRECT) - kfree(phys_to_virt(vq->vring.desc[i].addr)); - - while (vq->vring.desc[i].flags & VRING_DESC_F_NEXT) { - i = vq->vring.desc[i].next; - vq->vq.num_free++; - } - - vq->vring.desc[i].next = vq->free_head; - vq->free_head = head; - /* Plus final descriptor */ - vq->vq.num_free++; -} - -static inline bool more_used(const struct vring_virtqueue *vq) -{ - return vq->last_used_idx != vq->vring.used->idx; -} - /** - * virtqueue_get_buf - get the next used buffer - * @vq: the struct virtqueue we're talking about. + * virtqueue_get_buf_ctx - get the next used buffer + * @_vq: the struct virtqueue we're talking about. * @len: the length written into the buffer + * @ctx: extra context for the token * - * If the driver wrote data into the buffer, @len will be set to the + * If the device wrote data into the buffer, @len will be set to the * amount written. This means you don't need to clear the buffer * beforehand to ensure there's no data leakage in the case of short * writes. @@ -501,66 +2535,24 @@ static inline bool more_used(const struct vring_virtqueue *vq) * Returns NULL if there are no used buffers, or the "data" token * handed to virtqueue_add_*(). */ -void *virtqueue_get_buf(struct virtqueue *_vq, unsigned int *len) +void *virtqueue_get_buf_ctx(struct virtqueue *_vq, unsigned int *len, + void **ctx) { struct vring_virtqueue *vq = to_vvq(_vq); - void *ret; - unsigned int i; - u16 last_used; - - START_USE(vq); - if (unlikely(vq->broken)) { - END_USE(vq); - return NULL; - } - - if (!more_used(vq)) { - pr_debug("No more buffers in queue\n"); - END_USE(vq); - return NULL; - } - - /* Only get used array entries after they have been exposed by host. */ - virtio_rmb(vq->weak_barriers); - - last_used = (vq->last_used_idx & (vq->vring.num - 1)); - i = vq->vring.used->ring[last_used].id; - *len = vq->vring.used->ring[last_used].len; - - if (unlikely(i >= vq->vring.num)) { - BAD_RING(vq, "id %u out of range\n", i); - return NULL; - } - if (unlikely(!vq->data[i])) { - BAD_RING(vq, "id %u is not a head!\n", i); - return NULL; - } - - /* detach_buf clears data, so grab it now. */ - ret = vq->data[i]; - detach_buf(vq, i); - vq->last_used_idx++; - /* If we expect an interrupt for the next entry, tell host - * by writing event index and flush out the write before - * the read in the next get_buf call. */ - if (!(vq->vring.avail->flags & VRING_AVAIL_F_NO_INTERRUPT)) { - vring_used_event(&vq->vring) = vq->last_used_idx; - virtio_mb(vq->weak_barriers); - } - -#ifdef DEBUG - vq->last_add_time_valid = false; -#endif + return vq->packed_ring ? virtqueue_get_buf_ctx_packed(_vq, len, ctx) : + virtqueue_get_buf_ctx_split(_vq, len, ctx); +} +EXPORT_SYMBOL_GPL(virtqueue_get_buf_ctx); - END_USE(vq); - return ret; +void *virtqueue_get_buf(struct virtqueue *_vq, unsigned int *len) +{ + return virtqueue_get_buf_ctx(_vq, len, NULL); } EXPORT_SYMBOL_GPL(virtqueue_get_buf); - /** * virtqueue_disable_cb - disable callbacks - * @vq: the struct virtqueue we're talking about. + * @_vq: the struct virtqueue we're talking about. * * Note that this is not necessarily synchronous, hence unreliable and only * useful as an optimization. @@ -571,13 +2563,16 @@ void virtqueue_disable_cb(struct virtqueue *_vq) { struct vring_virtqueue *vq = to_vvq(_vq); - vq->vring.avail->flags |= VRING_AVAIL_F_NO_INTERRUPT; + if (vq->packed_ring) + virtqueue_disable_cb_packed(_vq); + else + virtqueue_disable_cb_split(_vq); } EXPORT_SYMBOL_GPL(virtqueue_disable_cb); /** * virtqueue_enable_cb_prepare - restart callbacks after disable_cb - * @vq: the struct virtqueue we're talking about. + * @_vq: the struct virtqueue we're talking about. * * This re-enables callbacks; it returns current queue state * in an opaque unsigned value. This value should be later tested by @@ -587,46 +2582,43 @@ EXPORT_SYMBOL_GPL(virtqueue_disable_cb); * Caller must ensure we don't call this with other virtqueue * operations at the same time (except where noted). */ -unsigned virtqueue_enable_cb_prepare(struct virtqueue *_vq) +unsigned int virtqueue_enable_cb_prepare(struct virtqueue *_vq) { struct vring_virtqueue *vq = to_vvq(_vq); - u16 last_used_idx; - START_USE(vq); + if (vq->event_triggered) + vq->event_triggered = false; - /* We optimistically turn back on interrupts, then check if there was - * more to do. */ - /* Depending on the VIRTIO_RING_F_EVENT_IDX feature, we need to - * either clear the flags bit or point the event index at the next - * entry. Always do both to keep code simple. */ - vq->vring.avail->flags &= ~VRING_AVAIL_F_NO_INTERRUPT; - vring_used_event(&vq->vring) = last_used_idx = vq->last_used_idx; - END_USE(vq); - return last_used_idx; + return vq->packed_ring ? virtqueue_enable_cb_prepare_packed(_vq) : + virtqueue_enable_cb_prepare_split(_vq); } EXPORT_SYMBOL_GPL(virtqueue_enable_cb_prepare); /** * virtqueue_poll - query pending used buffers - * @vq: the struct virtqueue we're talking about. + * @_vq: the struct virtqueue we're talking about. * @last_used_idx: virtqueue state (from call to virtqueue_enable_cb_prepare). * * Returns "true" if there are pending used buffers in the queue. * * This does not need to be serialized. */ -bool virtqueue_poll(struct virtqueue *_vq, unsigned last_used_idx) +bool virtqueue_poll(struct virtqueue *_vq, unsigned int last_used_idx) { struct vring_virtqueue *vq = to_vvq(_vq); + if (unlikely(vq->broken)) + return false; + virtio_mb(vq->weak_barriers); - return (u16)last_used_idx != vq->vring.used->idx; + return vq->packed_ring ? virtqueue_poll_packed(_vq, last_used_idx) : + virtqueue_poll_split(_vq, last_used_idx); } EXPORT_SYMBOL_GPL(virtqueue_poll); /** * virtqueue_enable_cb - restart callbacks after disable_cb. - * @vq: the struct virtqueue we're talking about. + * @_vq: the struct virtqueue we're talking about. * * This re-enables callbacks; it returns "false" if there are pending * buffers in the queue, to detect a possible race between the driver @@ -637,14 +2629,15 @@ EXPORT_SYMBOL_GPL(virtqueue_poll); */ bool virtqueue_enable_cb(struct virtqueue *_vq) { - unsigned last_used_idx = virtqueue_enable_cb_prepare(_vq); + unsigned int last_used_idx = virtqueue_enable_cb_prepare(_vq); + return !virtqueue_poll(_vq, last_used_idx); } EXPORT_SYMBOL_GPL(virtqueue_enable_cb); /** * virtqueue_enable_cb_delayed - restart callbacks after disable_cb. - * @vq: the struct virtqueue we're talking about. + * @_vq: the struct virtqueue we're talking about. * * This re-enables callbacks but hints to the other side to delay * interrupts until most of the available buffers have been processed; @@ -658,64 +2651,45 @@ EXPORT_SYMBOL_GPL(virtqueue_enable_cb); bool virtqueue_enable_cb_delayed(struct virtqueue *_vq) { struct vring_virtqueue *vq = to_vvq(_vq); - u16 bufs; - - START_USE(vq); - /* We optimistically turn back on interrupts, then check if there was - * more to do. */ - /* Depending on the VIRTIO_RING_F_USED_EVENT_IDX feature, we need to - * either clear the flags bit or point the event index at the next - * entry. Always do both to keep code simple. */ - vq->vring.avail->flags &= ~VRING_AVAIL_F_NO_INTERRUPT; - /* TODO: tune this threshold */ - bufs = (u16)(vq->vring.avail->idx - vq->last_used_idx) * 3 / 4; - vring_used_event(&vq->vring) = vq->last_used_idx + bufs; - virtio_mb(vq->weak_barriers); - if (unlikely((u16)(vq->vring.used->idx - vq->last_used_idx) > bufs)) { - END_USE(vq); - return false; - } + if (vq->event_triggered) + data_race(vq->event_triggered = false); - END_USE(vq); - return true; + return vq->packed_ring ? virtqueue_enable_cb_delayed_packed(_vq) : + virtqueue_enable_cb_delayed_split(_vq); } EXPORT_SYMBOL_GPL(virtqueue_enable_cb_delayed); /** * virtqueue_detach_unused_buf - detach first unused buffer - * @vq: the struct virtqueue we're talking about. + * @_vq: the struct virtqueue we're talking about. * * Returns NULL or the "data" token handed to virtqueue_add_*(). - * This is not valid on an active queue; it is useful only for device - * shutdown. + * This is not valid on an active queue; it is useful for device + * shutdown or the reset queue. */ void *virtqueue_detach_unused_buf(struct virtqueue *_vq) { struct vring_virtqueue *vq = to_vvq(_vq); - unsigned int i; - void *buf; - - START_USE(vq); - for (i = 0; i < vq->vring.num; i++) { - if (!vq->data[i]) - continue; - /* detach_buf clears data, so grab it now. */ - buf = vq->data[i]; - detach_buf(vq, i); - vq->vring.avail->idx--; - END_USE(vq); - return buf; - } - /* That should have freed everything. */ - BUG_ON(vq->vq.num_free != vq->vring.num); - - END_USE(vq); - return NULL; + return vq->packed_ring ? virtqueue_detach_unused_buf_packed(_vq) : + virtqueue_detach_unused_buf_split(_vq); } EXPORT_SYMBOL_GPL(virtqueue_detach_unused_buf); +static inline bool more_used(const struct vring_virtqueue *vq) +{ + return vq->packed_ring ? more_used_packed(vq) : more_used_split(vq); +} + +/** + * vring_interrupt - notify a virtqueue on an interrupt + * @irq: the IRQ number (ignored) + * @_vq: the struct virtqueue to notify + * + * Calls the callback function of @_vq to process the virtqueue + * notification. + */ irqreturn_t vring_interrupt(int irq, void *_vq) { struct vring_virtqueue *vq = to_vvq(_vq); @@ -725,8 +2699,19 @@ irqreturn_t vring_interrupt(int irq, void *_vq) return IRQ_NONE; } - if (unlikely(vq->broken)) + if (unlikely(vq->broken)) { +#ifdef CONFIG_VIRTIO_HARDEN_NOTIFICATION + dev_warn_once(&vq->vq.vdev->dev, + "virtio vring IRQ raised before DRIVER_OK"); + return IRQ_NONE; +#else return IRQ_HANDLED; +#endif + } + + /* Just a hint for performance: so it's ok that this can be racy! */ + if (vq->event) + data_race(vq->event_triggered = true); pr_debug("virtqueue callback for %p (%p)\n", vq, vq->vq.callback); if (vq->vq.callback) @@ -736,71 +2721,255 @@ irqreturn_t vring_interrupt(int irq, void *_vq) } EXPORT_SYMBOL_GPL(vring_interrupt); +struct virtqueue *vring_create_virtqueue( + unsigned int index, + unsigned int num, + unsigned int vring_align, + struct virtio_device *vdev, + bool weak_barriers, + bool may_reduce_num, + bool context, + bool (*notify)(struct virtqueue *), + void (*callback)(struct virtqueue *), + const char *name) +{ + union virtio_map map = {.dma_dev = vdev->dev.parent}; + + if (virtio_has_feature(vdev, VIRTIO_F_RING_PACKED)) + return vring_create_virtqueue_packed(index, num, vring_align, + vdev, weak_barriers, may_reduce_num, + context, notify, callback, name, map); + + return vring_create_virtqueue_split(index, num, vring_align, + vdev, weak_barriers, may_reduce_num, + context, notify, callback, name, map); +} +EXPORT_SYMBOL_GPL(vring_create_virtqueue); + +struct virtqueue *vring_create_virtqueue_map( + unsigned int index, + unsigned int num, + unsigned int vring_align, + struct virtio_device *vdev, + bool weak_barriers, + bool may_reduce_num, + bool context, + bool (*notify)(struct virtqueue *), + void (*callback)(struct virtqueue *), + const char *name, + union virtio_map map) +{ + + if (virtio_has_feature(vdev, VIRTIO_F_RING_PACKED)) + return vring_create_virtqueue_packed(index, num, vring_align, + vdev, weak_barriers, may_reduce_num, + context, notify, callback, name, map); + + return vring_create_virtqueue_split(index, num, vring_align, + vdev, weak_barriers, may_reduce_num, + context, notify, callback, name, map); +} +EXPORT_SYMBOL_GPL(vring_create_virtqueue_map); + +/** + * virtqueue_resize - resize the vring of vq + * @_vq: the struct virtqueue we're talking about. + * @num: new ring num + * @recycle: callback to recycle unused buffers + * @recycle_done: callback to be invoked when recycle for all unused buffers done + * + * When it is really necessary to create a new vring, it will set the current vq + * into the reset state. Then call the passed callback to recycle the buffer + * that is no longer used. Only after the new vring is successfully created, the + * old vring will be released. + * + * Caller must ensure we don't call this with other virtqueue operations + * at the same time (except where noted). + * + * Returns zero or a negative error. + * 0: success. + * -ENOMEM: Failed to allocate a new ring, fall back to the original ring size. + * vq can still work normally + * -EBUSY: Failed to sync with device, vq may not work properly + * -ENOENT: Transport or device not supported + * -E2BIG/-EINVAL: num error + * -EPERM: Operation not permitted + * + */ +int virtqueue_resize(struct virtqueue *_vq, u32 num, + void (*recycle)(struct virtqueue *vq, void *buf), + void (*recycle_done)(struct virtqueue *vq)) +{ + struct vring_virtqueue *vq = to_vvq(_vq); + int err, err_reset; + + if (num > vq->vq.num_max) + return -E2BIG; + + if (!num) + return -EINVAL; + + if ((vq->packed_ring ? vq->packed.vring.num : vq->split.vring.num) == num) + return 0; + + err = virtqueue_disable_and_recycle(_vq, recycle); + if (err) + return err; + if (recycle_done) + recycle_done(_vq); + + if (vq->packed_ring) + err = virtqueue_resize_packed(_vq, num); + else + err = virtqueue_resize_split(_vq, num); + + err_reset = virtqueue_enable_after_reset(_vq); + if (err_reset) + return err_reset; + + return err; +} +EXPORT_SYMBOL_GPL(virtqueue_resize); + +/** + * virtqueue_reset - detach and recycle all unused buffers + * @_vq: the struct virtqueue we're talking about. + * @recycle: callback to recycle unused buffers + * @recycle_done: callback to be invoked when recycle for all unused buffers done + * + * Caller must ensure we don't call this with other virtqueue operations + * at the same time (except where noted). + * + * Returns zero or a negative error. + * 0: success. + * -EBUSY: Failed to sync with device, vq may not work properly + * -ENOENT: Transport or device not supported + * -EPERM: Operation not permitted + */ +int virtqueue_reset(struct virtqueue *_vq, + void (*recycle)(struct virtqueue *vq, void *buf), + void (*recycle_done)(struct virtqueue *vq)) +{ + struct vring_virtqueue *vq = to_vvq(_vq); + int err; + + err = virtqueue_disable_and_recycle(_vq, recycle); + if (err) + return err; + if (recycle_done) + recycle_done(_vq); + + if (vq->packed_ring) + virtqueue_reinit_packed(vq); + else + virtqueue_reinit_split(vq); + + return virtqueue_enable_after_reset(_vq); +} +EXPORT_SYMBOL_GPL(virtqueue_reset); + struct virtqueue *vring_new_virtqueue(unsigned int index, unsigned int num, unsigned int vring_align, struct virtio_device *vdev, bool weak_barriers, + bool context, void *pages, - void (*notify)(struct virtqueue *), - void (*callback)(struct virtqueue *), + bool (*notify)(struct virtqueue *vq), + void (*callback)(struct virtqueue *vq), const char *name) { - struct vring_virtqueue *vq; - unsigned int i; - - /* We assume num is a power of 2. */ - if (num & (num - 1)) { - dev_warn(&vdev->dev, "Bad virtqueue length %u\n", num); - return NULL; + struct vring_virtqueue_split vring_split = {}; + union virtio_map map = {.dma_dev = vdev->dev.parent}; + + if (virtio_has_feature(vdev, VIRTIO_F_RING_PACKED)) { + struct vring_virtqueue_packed vring_packed = {}; + + vring_packed.vring.num = num; + vring_packed.vring.desc = pages; + return __vring_new_virtqueue_packed(index, &vring_packed, + vdev, weak_barriers, + context, notify, callback, + name, map); } - vq = kmalloc(sizeof(*vq) + sizeof(void *)*num, GFP_KERNEL); - if (!vq) - return NULL; + vring_init(&vring_split.vring, num, pages, vring_align); + return __vring_new_virtqueue_split(index, &vring_split, vdev, weak_barriers, + context, notify, callback, name, + map); +} +EXPORT_SYMBOL_GPL(vring_new_virtqueue); - vring_init(&vq->vring, num, pages, vring_align); - vq->vq.callback = callback; - vq->vq.vdev = vdev; - vq->vq.name = name; - vq->vq.num_free = num; - vq->vq.index = index; - vq->notify = notify; - vq->weak_barriers = weak_barriers; - vq->broken = false; - vq->last_used_idx = 0; - vq->num_added = 0; - list_add_tail(&vq->vq.list, &vdev->vqs); -#ifdef DEBUG - vq->in_use = false; - vq->last_add_time_valid = false; -#endif +static void vring_free(struct virtqueue *_vq) +{ + struct vring_virtqueue *vq = to_vvq(_vq); - vq->indirect = virtio_has_feature(vdev, VIRTIO_RING_F_INDIRECT_DESC); - vq->event = virtio_has_feature(vdev, VIRTIO_RING_F_EVENT_IDX); + if (vq->we_own_ring) { + if (vq->packed_ring) { + vring_free_queue(vq->vq.vdev, + vq->packed.ring_size_in_bytes, + vq->packed.vring.desc, + vq->packed.ring_dma_addr, + vq->map); + + vring_free_queue(vq->vq.vdev, + vq->packed.event_size_in_bytes, + vq->packed.vring.driver, + vq->packed.driver_event_dma_addr, + vq->map); + + vring_free_queue(vq->vq.vdev, + vq->packed.event_size_in_bytes, + vq->packed.vring.device, + vq->packed.device_event_dma_addr, + vq->map); + + kfree(vq->packed.desc_state); + kfree(vq->packed.desc_extra); + } else { + vring_free_queue(vq->vq.vdev, + vq->split.queue_size_in_bytes, + vq->split.vring.desc, + vq->split.queue_dma_addr, + vq->map); + } + } + if (!vq->packed_ring) { + kfree(vq->split.desc_state); + kfree(vq->split.desc_extra); + } +} - /* No callback? Tell other side not to bother us. */ - if (!callback) - vq->vring.avail->flags |= VRING_AVAIL_F_NO_INTERRUPT; +void vring_del_virtqueue(struct virtqueue *_vq) +{ + struct vring_virtqueue *vq = to_vvq(_vq); - /* Put everything in free lists. */ - vq->free_head = 0; - for (i = 0; i < num-1; i++) { - vq->vring.desc[i].next = i+1; - vq->data[i] = NULL; - } - vq->data[i] = NULL; + spin_lock(&vq->vq.vdev->vqs_list_lock); + list_del(&_vq->list); + spin_unlock(&vq->vq.vdev->vqs_list_lock); - return &vq->vq; + vring_free(_vq); + + kfree(vq); } -EXPORT_SYMBOL_GPL(vring_new_virtqueue); +EXPORT_SYMBOL_GPL(vring_del_virtqueue); -void vring_del_virtqueue(struct virtqueue *vq) +u32 vring_notification_data(struct virtqueue *_vq) { - list_del(&vq->list); - kfree(to_vvq(vq)); + struct vring_virtqueue *vq = to_vvq(_vq); + u16 next; + + if (vq->packed_ring) + next = (vq->packed.next_avail_idx & + ~(-(1 << VRING_PACKED_EVENT_F_WRAP_CTR))) | + vq->packed.avail_wrap_counter << + VRING_PACKED_EVENT_F_WRAP_CTR; + else + next = vq->split.avail_idx_shadow; + + return next << 16 | _vq->index; } -EXPORT_SYMBOL_GPL(vring_del_virtqueue); +EXPORT_SYMBOL_GPL(vring_notification_data); /* Manipulates transport-specific feature bits. */ void vring_transport_features(struct virtio_device *vdev) @@ -813,9 +2982,19 @@ void vring_transport_features(struct virtio_device *vdev) break; case VIRTIO_RING_F_EVENT_IDX: break; + case VIRTIO_F_VERSION_1: + break; + case VIRTIO_F_ACCESS_PLATFORM: + break; + case VIRTIO_F_RING_PACKED: + break; + case VIRTIO_F_ORDER_PLATFORM: + break; + case VIRTIO_F_NOTIFICATION_DATA: + break; default: /* We don't understand this bit. */ - clear_bit(i, vdev->features); + __virtio_clear_bit(vdev, i); } } } @@ -823,18 +3002,406 @@ EXPORT_SYMBOL_GPL(vring_transport_features); /** * virtqueue_get_vring_size - return the size of the virtqueue's vring - * @vq: the struct virtqueue containing the vring of interest. + * @_vq: the struct virtqueue containing the vring of interest. * * Returns the size of the vring. This is mainly used for boasting to * userspace. Unlike other operations, this need not be serialized. */ -unsigned int virtqueue_get_vring_size(struct virtqueue *_vq) +unsigned int virtqueue_get_vring_size(const struct virtqueue *_vq) { - struct vring_virtqueue *vq = to_vvq(_vq); + const struct vring_virtqueue *vq = to_vvq(_vq); - return vq->vring.num; + return vq->packed_ring ? vq->packed.vring.num : vq->split.vring.num; } EXPORT_SYMBOL_GPL(virtqueue_get_vring_size); +/* + * This function should only be called by the core, not directly by the driver. + */ +void __virtqueue_break(struct virtqueue *_vq) +{ + struct vring_virtqueue *vq = to_vvq(_vq); + + /* Pairs with READ_ONCE() in virtqueue_is_broken(). */ + WRITE_ONCE(vq->broken, true); +} +EXPORT_SYMBOL_GPL(__virtqueue_break); + +/* + * This function should only be called by the core, not directly by the driver. + */ +void __virtqueue_unbreak(struct virtqueue *_vq) +{ + struct vring_virtqueue *vq = to_vvq(_vq); + + /* Pairs with READ_ONCE() in virtqueue_is_broken(). */ + WRITE_ONCE(vq->broken, false); +} +EXPORT_SYMBOL_GPL(__virtqueue_unbreak); + +bool virtqueue_is_broken(const struct virtqueue *_vq) +{ + const struct vring_virtqueue *vq = to_vvq(_vq); + + return READ_ONCE(vq->broken); +} +EXPORT_SYMBOL_GPL(virtqueue_is_broken); + +/* + * This should prevent the device from being used, allowing drivers to + * recover. You may need to grab appropriate locks to flush. + */ +void virtio_break_device(struct virtio_device *dev) +{ + struct virtqueue *_vq; + + spin_lock(&dev->vqs_list_lock); + list_for_each_entry(_vq, &dev->vqs, list) { + struct vring_virtqueue *vq = to_vvq(_vq); + + /* Pairs with READ_ONCE() in virtqueue_is_broken(). */ + WRITE_ONCE(vq->broken, true); + } + spin_unlock(&dev->vqs_list_lock); +} +EXPORT_SYMBOL_GPL(virtio_break_device); + +/* + * This should allow the device to be used by the driver. You may + * need to grab appropriate locks to flush the write to + * vq->broken. This should only be used in some specific case e.g + * (probing and restoring). This function should only be called by the + * core, not directly by the driver. + */ +void __virtio_unbreak_device(struct virtio_device *dev) +{ + struct virtqueue *_vq; + + spin_lock(&dev->vqs_list_lock); + list_for_each_entry(_vq, &dev->vqs, list) { + struct vring_virtqueue *vq = to_vvq(_vq); + + /* Pairs with READ_ONCE() in virtqueue_is_broken(). */ + WRITE_ONCE(vq->broken, false); + } + spin_unlock(&dev->vqs_list_lock); +} +EXPORT_SYMBOL_GPL(__virtio_unbreak_device); + +dma_addr_t virtqueue_get_desc_addr(const struct virtqueue *_vq) +{ + const struct vring_virtqueue *vq = to_vvq(_vq); + + BUG_ON(!vq->we_own_ring); + + if (vq->packed_ring) + return vq->packed.ring_dma_addr; + + return vq->split.queue_dma_addr; +} +EXPORT_SYMBOL_GPL(virtqueue_get_desc_addr); + +dma_addr_t virtqueue_get_avail_addr(const struct virtqueue *_vq) +{ + const struct vring_virtqueue *vq = to_vvq(_vq); + + BUG_ON(!vq->we_own_ring); + + if (vq->packed_ring) + return vq->packed.driver_event_dma_addr; + + return vq->split.queue_dma_addr + + ((char *)vq->split.vring.avail - (char *)vq->split.vring.desc); +} +EXPORT_SYMBOL_GPL(virtqueue_get_avail_addr); + +dma_addr_t virtqueue_get_used_addr(const struct virtqueue *_vq) +{ + const struct vring_virtqueue *vq = to_vvq(_vq); + + BUG_ON(!vq->we_own_ring); + + if (vq->packed_ring) + return vq->packed.device_event_dma_addr; + + return vq->split.queue_dma_addr + + ((char *)vq->split.vring.used - (char *)vq->split.vring.desc); +} +EXPORT_SYMBOL_GPL(virtqueue_get_used_addr); + +/* Only available for split ring */ +const struct vring *virtqueue_get_vring(const struct virtqueue *vq) +{ + return &to_vvq(vq)->split.vring; +} +EXPORT_SYMBOL_GPL(virtqueue_get_vring); + +/** + * virtqueue_map_alloc_coherent - alloc coherent mapping + * @vdev: the virtio device we are talking to + * @map: metadata for performing mapping + * @size: the size of the buffer + * @map_handle: the pointer to the mapped address + * @gfp: allocation flag (GFP_XXX) + * + * return virtual address or NULL on error + */ +void *virtqueue_map_alloc_coherent(struct virtio_device *vdev, + union virtio_map map, + size_t size, dma_addr_t *map_handle, + gfp_t gfp) +{ + if (vdev->map) + return vdev->map->alloc(map, size, + map_handle, gfp); + else + return dma_alloc_coherent(map.dma_dev, size, + map_handle, gfp); +} +EXPORT_SYMBOL_GPL(virtqueue_map_alloc_coherent); + +/** + * virtqueue_map_free_coherent - free coherent mapping + * @vdev: the virtio device we are talking to + * @map: metadata for performing mapping + * @size: the size of the buffer + * @vaddr: the virtual address that needs to be freed + * @map_handle: the mapped address that needs to be freed + * + */ +void virtqueue_map_free_coherent(struct virtio_device *vdev, + union virtio_map map, size_t size, void *vaddr, + dma_addr_t map_handle) +{ + if (vdev->map) + vdev->map->free(map, size, vaddr, + map_handle, 0); + else + dma_free_coherent(map.dma_dev, size, vaddr, map_handle); +} +EXPORT_SYMBOL_GPL(virtqueue_map_free_coherent); + +/** + * virtqueue_map_page_attrs - map a page to the device + * @_vq: the virtqueue we are talking to + * @page: the page that will be mapped by the device + * @offset: the offset in the page for a buffer + * @size: the buffer size + * @dir: mapping direction + * @attrs: mapping attributes + * + * Returns mapped address. Caller should check that by virtqueue_map_mapping_error(). + */ +dma_addr_t virtqueue_map_page_attrs(const struct virtqueue *_vq, + struct page *page, + unsigned long offset, + size_t size, + enum dma_data_direction dir, + unsigned long attrs) +{ + const struct vring_virtqueue *vq = to_vvq(_vq); + struct virtio_device *vdev = _vq->vdev; + + if (vdev->map) + return vdev->map->map_page(vq->map, + page, offset, size, + dir, attrs); + + return dma_map_page_attrs(vring_dma_dev(vq), + page, offset, size, + dir, attrs); +} +EXPORT_SYMBOL_GPL(virtqueue_map_page_attrs); + +/** + * virtqueue_unmap_page_attrs - map a page to the device + * @_vq: the virtqueue we are talking to + * @map_handle: the mapped address + * @size: the buffer size + * @dir: mapping direction + * @attrs: unmapping attributes + */ +void virtqueue_unmap_page_attrs(const struct virtqueue *_vq, + dma_addr_t map_handle, + size_t size, enum dma_data_direction dir, + unsigned long attrs) +{ + const struct vring_virtqueue *vq = to_vvq(_vq); + struct virtio_device *vdev = _vq->vdev; + + if (vdev->map) + vdev->map->unmap_page(vq->map, + map_handle, size, dir, attrs); + else + dma_unmap_page_attrs(vring_dma_dev(vq), map_handle, + size, dir, attrs); +} +EXPORT_SYMBOL_GPL(virtqueue_unmap_page_attrs); + +/** + * virtqueue_map_single_attrs - map DMA for _vq + * @_vq: the struct virtqueue we're talking about. + * @ptr: the pointer of the buffer to do dma + * @size: the size of the buffer to do dma + * @dir: DMA direction + * @attrs: DMA Attrs + * + * The caller calls this to do dma mapping in advance. The DMA address can be + * passed to this _vq when it is in pre-mapped mode. + * + * return mapped address. Caller should check that by virtqueue_map_mapping_error(). + */ +dma_addr_t virtqueue_map_single_attrs(const struct virtqueue *_vq, void *ptr, + size_t size, + enum dma_data_direction dir, + unsigned long attrs) +{ + const struct vring_virtqueue *vq = to_vvq(_vq); + + if (!vq->use_map_api) { + kmsan_handle_dma(virt_to_phys(ptr), size, dir); + return (dma_addr_t)virt_to_phys(ptr); + } + + /* DMA must never operate on areas that might be remapped. */ + if (dev_WARN_ONCE(&_vq->vdev->dev, is_vmalloc_addr(ptr), + "rejecting DMA map of vmalloc memory\n")) + return DMA_MAPPING_ERROR; + + return virtqueue_map_page_attrs(&vq->vq, virt_to_page(ptr), + offset_in_page(ptr), size, dir, attrs); +} +EXPORT_SYMBOL_GPL(virtqueue_map_single_attrs); + +/** + * virtqueue_unmap_single_attrs - unmap map for _vq + * @_vq: the struct virtqueue we're talking about. + * @addr: the dma address to unmap + * @size: the size of the buffer + * @dir: DMA direction + * @attrs: DMA Attrs + * + * Unmap the address that is mapped by the virtqueue_map_* APIs. + * + */ +void virtqueue_unmap_single_attrs(const struct virtqueue *_vq, + dma_addr_t addr, + size_t size, enum dma_data_direction dir, + unsigned long attrs) +{ + const struct vring_virtqueue *vq = to_vvq(_vq); + + if (!vq->use_map_api) + return; + + virtqueue_unmap_page_attrs(_vq, addr, size, dir, attrs); +} +EXPORT_SYMBOL_GPL(virtqueue_unmap_single_attrs); + +/** + * virtqueue_map_mapping_error - check dma address + * @_vq: the struct virtqueue we're talking about. + * @addr: DMA address + * + * Returns 0 means dma valid. Other means invalid dma address. + */ +int virtqueue_map_mapping_error(const struct virtqueue *_vq, dma_addr_t addr) +{ + const struct vring_virtqueue *vq = to_vvq(_vq); + + return vring_mapping_error(vq, addr); +} +EXPORT_SYMBOL_GPL(virtqueue_map_mapping_error); + +/** + * virtqueue_map_need_sync - check a dma address needs sync + * @_vq: the struct virtqueue we're talking about. + * @addr: DMA address + * + * Check if the dma address mapped by the virtqueue_map_* APIs needs to be + * synchronized + * + * return bool + */ +bool virtqueue_map_need_sync(const struct virtqueue *_vq, dma_addr_t addr) +{ + const struct vring_virtqueue *vq = to_vvq(_vq); + struct virtio_device *vdev = _vq->vdev; + + if (!vq->use_map_api) + return false; + + if (vdev->map) + return vdev->map->need_sync(vq->map, addr); + else + return dma_need_sync(vring_dma_dev(vq), addr); +} +EXPORT_SYMBOL_GPL(virtqueue_map_need_sync); + +/** + * virtqueue_map_sync_single_range_for_cpu - map sync for cpu + * @_vq: the struct virtqueue we're talking about. + * @addr: DMA address + * @offset: DMA address offset + * @size: buf size for sync + * @dir: DMA direction + * + * Before calling this function, use virtqueue_map_need_sync() to confirm that + * the DMA address really needs to be synchronized + * + */ +void virtqueue_map_sync_single_range_for_cpu(const struct virtqueue *_vq, + dma_addr_t addr, + unsigned long offset, size_t size, + enum dma_data_direction dir) +{ + const struct vring_virtqueue *vq = to_vvq(_vq); + struct virtio_device *vdev = _vq->vdev; + + if (!vq->use_map_api) + return; + + if (vdev->map) + vdev->map->sync_single_for_cpu(vq->map, + addr + offset, size, dir); + else + dma_sync_single_range_for_cpu(vring_dma_dev(vq), + addr, offset, size, dir); +} +EXPORT_SYMBOL_GPL(virtqueue_map_sync_single_range_for_cpu); + +/** + * virtqueue_map_sync_single_range_for_device - map sync for device + * @_vq: the struct virtqueue we're talking about. + * @addr: DMA address + * @offset: DMA address offset + * @size: buf size for sync + * @dir: DMA direction + * + * Before calling this function, use virtqueue_map_need_sync() to confirm that + * the DMA address really needs to be synchronized + */ +void virtqueue_map_sync_single_range_for_device(const struct virtqueue *_vq, + dma_addr_t addr, + unsigned long offset, size_t size, + enum dma_data_direction dir) +{ + const struct vring_virtqueue *vq = to_vvq(_vq); + struct virtio_device *vdev = _vq->vdev; + + if (!vq->use_map_api) + return; + + if (vdev->map) + vdev->map->sync_single_for_device(vq->map, + addr + offset, + size, dir); + else + dma_sync_single_range_for_device(vring_dma_dev(vq), addr, + offset, size, dir); +} +EXPORT_SYMBOL_GPL(virtqueue_map_sync_single_range_for_device); + +MODULE_DESCRIPTION("Virtio ring implementation"); MODULE_LICENSE("GPL"); diff --git a/drivers/virtio/virtio_rtc_arm.c b/drivers/virtio/virtio_rtc_arm.c new file mode 100644 index 000000000000..211299d72870 --- /dev/null +++ b/drivers/virtio/virtio_rtc_arm.c @@ -0,0 +1,23 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * Provides cross-timestamp params for Arm. + * + * Copyright (C) 2022-2023 OpenSynergy GmbH + * Copyright (c) 2024 Qualcomm Innovation Center, Inc. All rights reserved. + */ + +#include <linux/clocksource_ids.h> + +#include <uapi/linux/virtio_rtc.h> + +#include "virtio_rtc_internal.h" + +/* see header for doc */ + +int viortc_hw_xtstamp_params(u8 *hw_counter, enum clocksource_ids *cs_id) +{ + *hw_counter = VIRTIO_RTC_COUNTER_ARM_VCT; + *cs_id = CSID_ARM_ARCH_COUNTER; + + return 0; +} diff --git a/drivers/virtio/virtio_rtc_class.c b/drivers/virtio/virtio_rtc_class.c new file mode 100644 index 000000000000..05d6d28255cf --- /dev/null +++ b/drivers/virtio/virtio_rtc_class.c @@ -0,0 +1,262 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * virtio_rtc RTC class driver + * + * Copyright (C) 2023 OpenSynergy GmbH + * Copyright (c) 2024 Qualcomm Innovation Center, Inc. All rights reserved. + */ + +#include <linux/math64.h> +#include <linux/overflow.h> +#include <linux/rtc.h> +#include <linux/time64.h> + +#include <uapi/linux/virtio_rtc.h> + +#include "virtio_rtc_internal.h" + +/** + * struct viortc_class - RTC class wrapper + * @viortc: virtio_rtc device data + * @rtc: RTC device + * @vio_clk_id: virtio_rtc clock id + * @stopped: Whether RTC ops are disallowed. Access protected by rtc_lock(). + */ +struct viortc_class { + struct viortc_dev *viortc; + struct rtc_device *rtc; + u16 vio_clk_id; + bool stopped; +}; + +/** + * viortc_class_get_locked() - get RTC class wrapper, if ops allowed + * @dev: virtio device + * + * Gets the RTC class wrapper from the virtio device, if it is available and + * ops are allowed. + * + * Context: Caller must hold rtc_lock(). + * Return: RTC class wrapper if available and ops allowed, ERR_PTR otherwise. + */ +static struct viortc_class *viortc_class_get_locked(struct device *dev) +{ + struct viortc_class *viortc_class; + + viortc_class = viortc_class_from_dev(dev); + if (IS_ERR(viortc_class)) + return viortc_class; + + if (viortc_class->stopped) + return ERR_PTR(-EBUSY); + + return viortc_class; +} + +/** + * viortc_class_read_time() - RTC class op read_time + * @dev: virtio device + * @tm: read time + * + * Context: Process context. + * Return: Zero on success, negative error code otherwise. + */ +static int viortc_class_read_time(struct device *dev, struct rtc_time *tm) +{ + struct viortc_class *viortc_class; + time64_t sec; + int ret; + u64 ns; + + viortc_class = viortc_class_get_locked(dev); + if (IS_ERR(viortc_class)) + return PTR_ERR(viortc_class); + + ret = viortc_read(viortc_class->viortc, viortc_class->vio_clk_id, &ns); + if (ret) + return ret; + + sec = div_u64(ns, NSEC_PER_SEC); + + rtc_time64_to_tm(sec, tm); + + return 0; +} + +/** + * viortc_class_read_alarm() - RTC class op read_alarm + * @dev: virtio device + * @alrm: alarm read out + * + * Context: Process context. + * Return: Zero on success, negative error code otherwise. + */ +static int viortc_class_read_alarm(struct device *dev, struct rtc_wkalrm *alrm) +{ + struct viortc_class *viortc_class; + time64_t alarm_time_sec; + u64 alarm_time_ns; + bool enabled; + int ret; + + viortc_class = viortc_class_get_locked(dev); + if (IS_ERR(viortc_class)) + return PTR_ERR(viortc_class); + + ret = viortc_read_alarm(viortc_class->viortc, viortc_class->vio_clk_id, + &alarm_time_ns, &enabled); + if (ret) + return ret; + + alarm_time_sec = div_u64(alarm_time_ns, NSEC_PER_SEC); + rtc_time64_to_tm(alarm_time_sec, &alrm->time); + + alrm->enabled = enabled; + + return 0; +} + +/** + * viortc_class_set_alarm() - RTC class op set_alarm + * @dev: virtio device + * @alrm: alarm to set + * + * Context: Process context. + * Return: Zero on success, negative error code otherwise. + */ +static int viortc_class_set_alarm(struct device *dev, struct rtc_wkalrm *alrm) +{ + struct viortc_class *viortc_class; + time64_t alarm_time_sec; + u64 alarm_time_ns; + + viortc_class = viortc_class_get_locked(dev); + if (IS_ERR(viortc_class)) + return PTR_ERR(viortc_class); + + alarm_time_sec = rtc_tm_to_time64(&alrm->time); + + if (alarm_time_sec < 0) + return -EINVAL; + + if (check_mul_overflow((u64)alarm_time_sec, (u64)NSEC_PER_SEC, + &alarm_time_ns)) + return -EINVAL; + + return viortc_set_alarm(viortc_class->viortc, viortc_class->vio_clk_id, + alarm_time_ns, alrm->enabled); +} + +/** + * viortc_class_alarm_irq_enable() - RTC class op alarm_irq_enable + * @dev: virtio device + * @enabled: enable or disable alarm IRQ + * + * Context: Process context. + * Return: Zero on success, negative error code otherwise. + */ +static int viortc_class_alarm_irq_enable(struct device *dev, + unsigned int enabled) +{ + struct viortc_class *viortc_class; + + viortc_class = viortc_class_get_locked(dev); + if (IS_ERR(viortc_class)) + return PTR_ERR(viortc_class); + + return viortc_set_alarm_enabled(viortc_class->viortc, + viortc_class->vio_clk_id, enabled); +} + +static const struct rtc_class_ops viortc_class_ops = { + .read_time = viortc_class_read_time, + .read_alarm = viortc_class_read_alarm, + .set_alarm = viortc_class_set_alarm, + .alarm_irq_enable = viortc_class_alarm_irq_enable, +}; + +/** + * viortc_class_alarm() - propagate alarm notification as alarm interrupt + * @viortc_class: RTC class wrapper + * @vio_clk_id: virtio_rtc clock id + * + * Context: Any context. + */ +void viortc_class_alarm(struct viortc_class *viortc_class, u16 vio_clk_id) +{ + if (vio_clk_id != viortc_class->vio_clk_id) { + dev_warn_ratelimited(&viortc_class->rtc->dev, + "ignoring alarm for clock id %d, expected id %d\n", + vio_clk_id, viortc_class->vio_clk_id); + return; + } + + rtc_update_irq(viortc_class->rtc, 1, RTC_AF | RTC_IRQF); +} + +/** + * viortc_class_stop() - disallow RTC class ops + * @viortc_class: RTC class wrapper + * + * Context: Process context. Caller must NOT hold rtc_lock(). + */ +void viortc_class_stop(struct viortc_class *viortc_class) +{ + rtc_lock(viortc_class->rtc); + + viortc_class->stopped = true; + + rtc_unlock(viortc_class->rtc); +} + +/** + * viortc_class_register() - register RTC class device + * @viortc_class: RTC class wrapper + * + * Context: Process context. + * Return: Zero on success, negative error code otherwise. + */ +int viortc_class_register(struct viortc_class *viortc_class) +{ + return devm_rtc_register_device(viortc_class->rtc); +} + +/** + * viortc_class_init() - init RTC class wrapper and device + * @viortc: device data + * @vio_clk_id: virtio_rtc clock id + * @have_alarm: have alarm feature + * @parent_dev: virtio device + * + * Context: Process context. + * Return: RTC class wrapper on success, ERR_PTR otherwise. + */ +struct viortc_class *viortc_class_init(struct viortc_dev *viortc, + u16 vio_clk_id, bool have_alarm, + struct device *parent_dev) +{ + struct viortc_class *viortc_class; + struct rtc_device *rtc; + + viortc_class = + devm_kzalloc(parent_dev, sizeof(*viortc_class), GFP_KERNEL); + if (!viortc_class) + return ERR_PTR(-ENOMEM); + + rtc = devm_rtc_allocate_device(parent_dev); + if (IS_ERR(rtc)) + return ERR_CAST(rtc); + + viortc_class->viortc = viortc; + viortc_class->rtc = rtc; + viortc_class->vio_clk_id = vio_clk_id; + + if (!have_alarm) + clear_bit(RTC_FEATURE_ALARM, rtc->features); + clear_bit(RTC_FEATURE_UPDATE_INTERRUPT, rtc->features); + + rtc->ops = &viortc_class_ops; + rtc->range_max = div_u64(U64_MAX, NSEC_PER_SEC); + + return viortc_class; +} diff --git a/drivers/virtio/virtio_rtc_driver.c b/drivers/virtio/virtio_rtc_driver.c new file mode 100644 index 000000000000..a57d5e06e19d --- /dev/null +++ b/drivers/virtio/virtio_rtc_driver.c @@ -0,0 +1,1407 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * virtio_rtc driver core + * + * Copyright (C) 2022-2024 OpenSynergy GmbH + * Copyright (c) 2024 Qualcomm Innovation Center, Inc. All rights reserved. + */ + +#include <linux/completion.h> +#include <linux/device.h> +#include <linux/module.h> +#include <linux/pm.h> +#include <linux/virtio.h> +#include <linux/virtio_config.h> +#include <linux/virtio_ids.h> + +#include <uapi/linux/virtio_rtc.h> + +#include "virtio_rtc_internal.h" + +#define VIORTC_ALARMQ_BUF_CAP sizeof(union virtio_rtc_notif_alarmq) + +/* virtqueue order */ +enum { + VIORTC_REQUESTQ, + VIORTC_ALARMQ, + VIORTC_MAX_NR_QUEUES, +}; + +/** + * struct viortc_vq - virtqueue abstraction + * @vq: virtqueue + * @lock: protects access to vq + */ +struct viortc_vq { + struct virtqueue *vq; + spinlock_t lock; +}; + +/** + * struct viortc_dev - virtio_rtc device data + * @vdev: virtio device + * @viortc_class: RTC class wrapper for UTC-like clock, NULL if not available + * @vqs: virtqueues + * @clocks_to_unregister: Clock references, which are only used during device + * removal. + * For other uses, there would be a race between device + * creation and setting the pointers here. + * @alarmq_bufs: alarmq buffers list + * @num_alarmq_bufs: # of alarmq buffers + * @num_clocks: # of virtio_rtc clocks + */ +struct viortc_dev { + struct virtio_device *vdev; + struct viortc_class *viortc_class; + struct viortc_vq vqs[VIORTC_MAX_NR_QUEUES]; + struct viortc_ptp_clock **clocks_to_unregister; + void **alarmq_bufs; + unsigned int num_alarmq_bufs; + u16 num_clocks; +}; + +/** + * struct viortc_msg - Message requested by driver, responded by device. + * @viortc: device data + * @req: request buffer + * @resp: response buffer + * @responded: vqueue callback signals response reception + * @refcnt: Message reference count, message and buffers will be deallocated + * once 0. refcnt is decremented in the vqueue callback and in the + * thread waiting on the responded completion. + * If a message response wait function times out, the message will be + * freed upon late reception (refcnt will reach 0 in the callback), or + * device removal. + * @req_size: size of request in bytes + * @resp_cap: maximum size of response in bytes + * @resp_actual_size: actual size of response + */ +struct viortc_msg { + struct viortc_dev *viortc; + void *req; + void *resp; + struct completion responded; + refcount_t refcnt; + unsigned int req_size; + unsigned int resp_cap; + unsigned int resp_actual_size; +}; + +/** + * viortc_class_from_dev() - Get RTC class object from virtio device. + * @dev: virtio device + * + * Context: Any context. + * Return: RTC class object if available, ERR_PTR otherwise. + */ +struct viortc_class *viortc_class_from_dev(struct device *dev) +{ + struct virtio_device *vdev; + struct viortc_dev *viortc; + + vdev = container_of(dev, typeof(*vdev), dev); + viortc = vdev->priv; + + return viortc->viortc_class ?: ERR_PTR(-ENODEV); +} + +/** + * viortc_alarms_supported() - Whether device and driver support alarms. + * @vdev: virtio device + * + * NB: Device and driver may not support alarms for the same clocks. + * + * Context: Any context. + * Return: True if both device and driver can support alarms. + */ +static bool viortc_alarms_supported(struct virtio_device *vdev) +{ + return IS_ENABLED(CONFIG_VIRTIO_RTC_CLASS) && + virtio_has_feature(vdev, VIRTIO_RTC_F_ALARM); +} + +/** + * viortc_feed_vq() - Make a device write-only buffer available. + * @viortc: device data + * @vq: notification virtqueue + * @buf: buffer + * @buf_len: buffer capacity in bytes + * @data: token, identifying buffer + * + * Context: Caller must prevent concurrent access to vq. + * Return: Zero on success, negative error code otherwise. + */ +static int viortc_feed_vq(struct viortc_dev *viortc, struct virtqueue *vq, + void *buf, unsigned int buf_len, void *data) +{ + struct scatterlist sg; + + sg_init_one(&sg, buf, buf_len); + + return virtqueue_add_inbuf(vq, &sg, 1, data, GFP_ATOMIC); +} + +/** + * viortc_msg_init() - Allocate and initialize requestq message. + * @viortc: device data + * @msg_type: virtio_rtc message type + * @req_size: size of request buffer to be allocated + * @resp_cap: size of response buffer to be allocated + * + * Initializes the message refcnt to 2. The refcnt will be decremented once in + * the virtqueue callback, and once in the thread waiting on the message (on + * completion or timeout). + * + * Context: Process context. + * Return: non-NULL on success. + */ +static struct viortc_msg *viortc_msg_init(struct viortc_dev *viortc, + u16 msg_type, unsigned int req_size, + unsigned int resp_cap) +{ + struct device *dev = &viortc->vdev->dev; + struct virtio_rtc_req_head *req_head; + struct viortc_msg *msg; + + msg = devm_kzalloc(dev, sizeof(*msg), GFP_KERNEL); + if (!msg) + return NULL; + + init_completion(&msg->responded); + + msg->req = devm_kzalloc(dev, req_size, GFP_KERNEL); + if (!msg->req) + goto err_free_msg; + + req_head = msg->req; + + msg->resp = devm_kzalloc(dev, resp_cap, GFP_KERNEL); + if (!msg->resp) + goto err_free_msg_req; + + msg->viortc = viortc; + msg->req_size = req_size; + msg->resp_cap = resp_cap; + + refcount_set(&msg->refcnt, 2); + + req_head->msg_type = virtio_cpu_to_le(msg_type, req_head->msg_type); + + return msg; + +err_free_msg_req: + devm_kfree(dev, msg->req); + +err_free_msg: + devm_kfree(dev, msg); + + return NULL; +} + +/** + * viortc_msg_release() - Decrement message refcnt, potentially free message. + * @msg: message requested by driver + * + * Context: Any context. + */ +static void viortc_msg_release(struct viortc_msg *msg) +{ + struct device *dev; + + if (refcount_dec_and_test(&msg->refcnt)) { + dev = &msg->viortc->vdev->dev; + + devm_kfree(dev, msg->req); + devm_kfree(dev, msg->resp); + devm_kfree(dev, msg); + } +} + +/** + * viortc_do_cb() - generic virtqueue callback logic + * @vq: virtqueue + * @handle_buf: function to process a used buffer + * + * Context: virtqueue callback, typically interrupt. Takes and releases vq lock. + */ +static void viortc_do_cb(struct virtqueue *vq, + void (*handle_buf)(void *token, unsigned int len, + struct virtqueue *vq, + struct viortc_vq *viortc_vq, + struct viortc_dev *viortc)) +{ + struct viortc_dev *viortc = vq->vdev->priv; + struct viortc_vq *viortc_vq; + bool cb_enabled = true; + unsigned long flags; + unsigned int len; + void *token; + + viortc_vq = &viortc->vqs[vq->index]; + + for (;;) { + spin_lock_irqsave(&viortc_vq->lock, flags); + + if (cb_enabled) { + virtqueue_disable_cb(vq); + cb_enabled = false; + } + + token = virtqueue_get_buf(vq, &len); + if (!token) { + if (virtqueue_enable_cb(vq)) { + spin_unlock_irqrestore(&viortc_vq->lock, flags); + return; + } + cb_enabled = true; + } + + spin_unlock_irqrestore(&viortc_vq->lock, flags); + + if (token) + handle_buf(token, len, vq, viortc_vq, viortc); + } +} + +/** + * viortc_requestq_hdlr() - process a requestq used buffer + * @token: token identifying the buffer + * @len: bytes written by device + * @vq: virtqueue + * @viortc_vq: device specific data for virtqueue + * @viortc: device data + * + * Signals completion for each received message. + * + * Context: virtqueue callback + */ +static void viortc_requestq_hdlr(void *token, unsigned int len, + struct virtqueue *vq, + struct viortc_vq *viortc_vq, + struct viortc_dev *viortc) +{ + struct viortc_msg *msg = token; + + msg->resp_actual_size = len; + + complete(&msg->responded); + viortc_msg_release(msg); +} + +/** + * viortc_cb_requestq() - callback for requestq + * @vq: virtqueue + * + * Context: virtqueue callback + */ +static void viortc_cb_requestq(struct virtqueue *vq) +{ + viortc_do_cb(vq, viortc_requestq_hdlr); +} + +/** + * viortc_alarmq_hdlr() - process an alarmq used buffer + * @token: token identifying the buffer + * @len: bytes written by device + * @vq: virtqueue + * @viortc_vq: device specific data for virtqueue + * @viortc: device data + * + * Processes a VIRTIO_RTC_NOTIF_ALARM notification by calling the RTC class + * driver. Makes the buffer available again. + * + * Context: virtqueue callback + */ +static void viortc_alarmq_hdlr(void *token, unsigned int len, + struct virtqueue *vq, + struct viortc_vq *viortc_vq, + struct viortc_dev *viortc) +{ + struct virtio_rtc_notif_alarm *notif = token; + struct virtio_rtc_notif_head *head = token; + unsigned long flags; + u16 clock_id; + bool notify; + + if (len < sizeof(*head)) { + dev_err_ratelimited(&viortc->vdev->dev, + "%s: ignoring notification with short header\n", + __func__); + goto feed_vq; + } + + if (virtio_le_to_cpu(head->msg_type) != VIRTIO_RTC_NOTIF_ALARM) { + dev_err_ratelimited(&viortc->vdev->dev, + "%s: ignoring unknown notification type 0x%x\n", + __func__, virtio_le_to_cpu(head->msg_type)); + goto feed_vq; + } + + if (len < sizeof(*notif)) { + dev_err_ratelimited(&viortc->vdev->dev, + "%s: ignoring too small alarm notification\n", + __func__); + goto feed_vq; + } + + clock_id = virtio_le_to_cpu(notif->clock_id); + + if (!viortc->viortc_class) + dev_warn_ratelimited(&viortc->vdev->dev, + "ignoring alarm, no RTC class device available\n"); + else + viortc_class_alarm(viortc->viortc_class, clock_id); + +feed_vq: + spin_lock_irqsave(&viortc_vq->lock, flags); + + if (viortc_feed_vq(viortc, vq, notif, VIORTC_ALARMQ_BUF_CAP, token)) + dev_warn(&viortc->vdev->dev, + "%s: failed to re-expose input buffer\n", __func__); + + notify = virtqueue_kick_prepare(vq); + + spin_unlock_irqrestore(&viortc_vq->lock, flags); + + if (notify) + virtqueue_notify(vq); +} + +/** + * viortc_cb_alarmq() - callback for alarmq + * @vq: virtqueue + * + * Context: virtqueue callback + */ +static void viortc_cb_alarmq(struct virtqueue *vq) +{ + viortc_do_cb(vq, viortc_alarmq_hdlr); +} + +/** + * viortc_get_resp_errno() - converts virtio_rtc errnos to system errnos + * @resp_head: message response header + * + * Return: negative system errno, or 0 + */ +static int viortc_get_resp_errno(struct virtio_rtc_resp_head *resp_head) +{ + switch (virtio_le_to_cpu(resp_head->status)) { + case VIRTIO_RTC_S_OK: + return 0; + case VIRTIO_RTC_S_EOPNOTSUPP: + return -EOPNOTSUPP; + case VIRTIO_RTC_S_EINVAL: + return -EINVAL; + case VIRTIO_RTC_S_ENODEV: + return -ENODEV; + case VIRTIO_RTC_S_EIO: + default: + return -EIO; + } +} + +/** + * viortc_msg_xfer() - send message request, wait until message response + * @vq: virtqueue + * @msg: message with driver request + * @timeout_jiffies: message response timeout, 0 for no timeout + * + * Context: Process context. Takes and releases vq.lock. May sleep. + * Return: Zero on success, negative error code otherwise. + */ +static int viortc_msg_xfer(struct viortc_vq *vq, struct viortc_msg *msg, + unsigned long timeout_jiffies) +{ + struct scatterlist out_sg[1]; + struct scatterlist in_sg[1]; + struct scatterlist *sgs[2]; + unsigned long flags; + long timeout_ret; + bool notify; + int ret; + + sgs[0] = out_sg; + sgs[1] = in_sg; + + sg_init_one(out_sg, msg->req, msg->req_size); + sg_init_one(in_sg, msg->resp, msg->resp_cap); + + spin_lock_irqsave(&vq->lock, flags); + + ret = virtqueue_add_sgs(vq->vq, sgs, 1, 1, msg, GFP_ATOMIC); + if (ret) { + spin_unlock_irqrestore(&vq->lock, flags); + /* + * Release in place of the response callback, which will never + * come. + */ + viortc_msg_release(msg); + return ret; + } + + notify = virtqueue_kick_prepare(vq->vq); + + spin_unlock_irqrestore(&vq->lock, flags); + + if (notify) + virtqueue_notify(vq->vq); + + if (timeout_jiffies) { + timeout_ret = wait_for_completion_interruptible_timeout( + &msg->responded, timeout_jiffies); + + if (!timeout_ret) + return -ETIMEDOUT; + else if (timeout_ret < 0) + return (int)timeout_ret; + } else { + ret = wait_for_completion_interruptible(&msg->responded); + if (ret) + return ret; + } + + if (msg->resp_actual_size < sizeof(struct virtio_rtc_resp_head)) + return -EINVAL; + + ret = viortc_get_resp_errno(msg->resp); + if (ret) + return ret; + + /* + * There is not yet a case where returning a short message would make + * sense, so consider any deviation an error. + */ + if (msg->resp_actual_size != msg->resp_cap) + return -EINVAL; + + return 0; +} + +/* + * common message handle macros for messages of different types + */ + +/** + * VIORTC_DECLARE_MSG_HDL_ONSTACK() - declare message handle on stack + * @hdl: message handle name + * @msg_id: message type id + * @msg_req: message request type + * @msg_resp: message response type + */ +#define VIORTC_DECLARE_MSG_HDL_ONSTACK(hdl, msg_id, msg_req, msg_resp) \ + struct { \ + struct viortc_msg *msg; \ + msg_req *req; \ + msg_resp *resp; \ + unsigned int req_size; \ + unsigned int resp_cap; \ + u16 msg_type; \ + } hdl = { \ + NULL, NULL, NULL, sizeof(msg_req), sizeof(msg_resp), (msg_id), \ + } + +/** + * VIORTC_MSG() - extract message from message handle + * @hdl: message handle + * + * Return: struct viortc_msg + */ +#define VIORTC_MSG(hdl) ((hdl).msg) + +/** + * VIORTC_MSG_INIT() - initialize message handle + * @hdl: message handle + * @viortc: device data (struct viortc_dev *) + * + * Context: Process context. + * Return: 0 on success, -ENOMEM otherwise. + */ +#define VIORTC_MSG_INIT(hdl, viortc) \ + ({ \ + typeof(hdl) *_hdl = &(hdl); \ + \ + _hdl->msg = viortc_msg_init((viortc), _hdl->msg_type, \ + _hdl->req_size, _hdl->resp_cap); \ + if (_hdl->msg) { \ + _hdl->req = _hdl->msg->req; \ + _hdl->resp = _hdl->msg->resp; \ + } \ + _hdl->msg ? 0 : -ENOMEM; \ + }) + +/** + * VIORTC_MSG_WRITE() - write a request message field + * @hdl: message handle + * @dest_member: request message field name + * @src_ptr: pointer to data of compatible type + * + * Writes the field in little-endian format. + */ +#define VIORTC_MSG_WRITE(hdl, dest_member, src_ptr) \ + do { \ + typeof(hdl) _hdl = (hdl); \ + typeof(src_ptr) _src_ptr = (src_ptr); \ + \ + /* Sanity check: must match the member's type */ \ + typecheck(typeof(virtio_le_to_cpu(_hdl.req->dest_member)), \ + *_src_ptr); \ + \ + _hdl.req->dest_member = \ + virtio_cpu_to_le(*_src_ptr, _hdl.req->dest_member); \ + } while (0) + +/** + * VIORTC_MSG_READ() - read from a response message field + * @hdl: message handle + * @src_member: response message field name + * @dest_ptr: pointer to data of compatible type + * + * Converts from little-endian format and writes to dest_ptr. + */ +#define VIORTC_MSG_READ(hdl, src_member, dest_ptr) \ + do { \ + typeof(dest_ptr) _dest_ptr = (dest_ptr); \ + \ + /* Sanity check: must match the member's type */ \ + typecheck(typeof(virtio_le_to_cpu((hdl).resp->src_member)), \ + *_dest_ptr); \ + \ + *_dest_ptr = virtio_le_to_cpu((hdl).resp->src_member); \ + } while (0) + +/* + * read requests + */ + +/** timeout for clock readings, where timeouts are considered non-fatal */ +#define VIORTC_MSG_READ_TIMEOUT secs_to_jiffies(60) + +/** + * viortc_read() - VIRTIO_RTC_REQ_READ wrapper + * @viortc: device data + * @vio_clk_id: virtio_rtc clock id + * @reading: clock reading [ns] + * + * Context: Process context. + * Return: Zero on success, negative error code otherwise. + */ +int viortc_read(struct viortc_dev *viortc, u16 vio_clk_id, u64 *reading) +{ + VIORTC_DECLARE_MSG_HDL_ONSTACK(hdl, VIRTIO_RTC_REQ_READ, + struct virtio_rtc_req_read, + struct virtio_rtc_resp_read); + int ret; + + ret = VIORTC_MSG_INIT(hdl, viortc); + if (ret) + return ret; + + VIORTC_MSG_WRITE(hdl, clock_id, &vio_clk_id); + + ret = viortc_msg_xfer(&viortc->vqs[VIORTC_REQUESTQ], VIORTC_MSG(hdl), + VIORTC_MSG_READ_TIMEOUT); + if (ret) { + dev_dbg(&viortc->vdev->dev, "%s: xfer returned %d\n", __func__, + ret); + goto out_release; + } + + VIORTC_MSG_READ(hdl, clock_reading, reading); + +out_release: + viortc_msg_release(VIORTC_MSG(hdl)); + + return ret; +} + +/** + * viortc_read_cross() - VIRTIO_RTC_REQ_READ_CROSS wrapper + * @viortc: device data + * @vio_clk_id: virtio_rtc clock id + * @hw_counter: virtio_rtc HW counter type + * @reading: clock reading [ns] + * @cycles: HW counter cycles during clock reading + * + * Context: Process context. + * Return: Zero on success, negative error code otherwise. + */ +int viortc_read_cross(struct viortc_dev *viortc, u16 vio_clk_id, u8 hw_counter, + u64 *reading, u64 *cycles) +{ + VIORTC_DECLARE_MSG_HDL_ONSTACK(hdl, VIRTIO_RTC_REQ_READ_CROSS, + struct virtio_rtc_req_read_cross, + struct virtio_rtc_resp_read_cross); + int ret; + + ret = VIORTC_MSG_INIT(hdl, viortc); + if (ret) + return ret; + + VIORTC_MSG_WRITE(hdl, clock_id, &vio_clk_id); + VIORTC_MSG_WRITE(hdl, hw_counter, &hw_counter); + + ret = viortc_msg_xfer(&viortc->vqs[VIORTC_REQUESTQ], VIORTC_MSG(hdl), + VIORTC_MSG_READ_TIMEOUT); + if (ret) { + dev_dbg(&viortc->vdev->dev, "%s: xfer returned %d\n", __func__, + ret); + goto out_release; + } + + VIORTC_MSG_READ(hdl, clock_reading, reading); + VIORTC_MSG_READ(hdl, counter_cycles, cycles); + +out_release: + viortc_msg_release(VIORTC_MSG(hdl)); + + return ret; +} + +/* + * control requests + */ + +/** + * viortc_cfg() - VIRTIO_RTC_REQ_CFG wrapper + * @viortc: device data + * @num_clocks: # of virtio_rtc clocks + * + * Context: Process context. + * Return: Zero on success, negative error code otherwise. + */ +static int viortc_cfg(struct viortc_dev *viortc, u16 *num_clocks) +{ + VIORTC_DECLARE_MSG_HDL_ONSTACK(hdl, VIRTIO_RTC_REQ_CFG, + struct virtio_rtc_req_cfg, + struct virtio_rtc_resp_cfg); + int ret; + + ret = VIORTC_MSG_INIT(hdl, viortc); + if (ret) + return ret; + + ret = viortc_msg_xfer(&viortc->vqs[VIORTC_REQUESTQ], VIORTC_MSG(hdl), + 0); + if (ret) { + dev_dbg(&viortc->vdev->dev, "%s: xfer returned %d\n", __func__, + ret); + goto out_release; + } + + VIORTC_MSG_READ(hdl, num_clocks, num_clocks); + +out_release: + viortc_msg_release(VIORTC_MSG(hdl)); + + return ret; +} + +/** + * viortc_clock_cap() - VIRTIO_RTC_REQ_CLOCK_CAP wrapper + * @viortc: device data + * @vio_clk_id: virtio_rtc clock id + * @type: virtio_rtc clock type + * @leap_second_smearing: virtio_rtc smearing variant + * @flags: struct virtio_rtc_resp_clock_cap.flags + * + * Context: Process context. + * Return: Zero on success, negative error code otherwise. + */ +static int viortc_clock_cap(struct viortc_dev *viortc, u16 vio_clk_id, u8 *type, + u8 *leap_second_smearing, u8 *flags) +{ + VIORTC_DECLARE_MSG_HDL_ONSTACK(hdl, VIRTIO_RTC_REQ_CLOCK_CAP, + struct virtio_rtc_req_clock_cap, + struct virtio_rtc_resp_clock_cap); + int ret; + + ret = VIORTC_MSG_INIT(hdl, viortc); + if (ret) + return ret; + + VIORTC_MSG_WRITE(hdl, clock_id, &vio_clk_id); + + ret = viortc_msg_xfer(&viortc->vqs[VIORTC_REQUESTQ], VIORTC_MSG(hdl), + 0); + if (ret) { + dev_dbg(&viortc->vdev->dev, "%s: xfer returned %d\n", __func__, + ret); + goto out_release; + } + + VIORTC_MSG_READ(hdl, type, type); + VIORTC_MSG_READ(hdl, leap_second_smearing, leap_second_smearing); + VIORTC_MSG_READ(hdl, flags, flags); + +out_release: + viortc_msg_release(VIORTC_MSG(hdl)); + + return ret; +} + +/** + * viortc_cross_cap() - VIRTIO_RTC_REQ_CROSS_CAP wrapper + * @viortc: device data + * @vio_clk_id: virtio_rtc clock id + * @hw_counter: virtio_rtc HW counter type + * @supported: xtstamping is supported for the vio_clk_id/hw_counter pair + * + * Context: Process context. + * Return: Zero on success, negative error code otherwise. + */ +int viortc_cross_cap(struct viortc_dev *viortc, u16 vio_clk_id, u8 hw_counter, + bool *supported) +{ + VIORTC_DECLARE_MSG_HDL_ONSTACK(hdl, VIRTIO_RTC_REQ_CROSS_CAP, + struct virtio_rtc_req_cross_cap, + struct virtio_rtc_resp_cross_cap); + u8 flags; + int ret; + + ret = VIORTC_MSG_INIT(hdl, viortc); + if (ret) + return ret; + + VIORTC_MSG_WRITE(hdl, clock_id, &vio_clk_id); + VIORTC_MSG_WRITE(hdl, hw_counter, &hw_counter); + + ret = viortc_msg_xfer(&viortc->vqs[VIORTC_REQUESTQ], VIORTC_MSG(hdl), + 0); + if (ret) { + dev_dbg(&viortc->vdev->dev, "%s: xfer returned %d\n", __func__, + ret); + goto out_release; + } + + VIORTC_MSG_READ(hdl, flags, &flags); + *supported = !!(flags & VIRTIO_RTC_FLAG_CROSS_CAP); + +out_release: + viortc_msg_release(VIORTC_MSG(hdl)); + + return ret; +} + +/** + * viortc_read_alarm() - VIRTIO_RTC_REQ_READ_ALARM wrapper + * @viortc: device data + * @vio_clk_id: virtio_rtc clock id + * @alarm_time: alarm time in ns + * @enabled: whether alarm is enabled + * + * Context: Process context. + * Return: Zero on success, negative error code otherwise. + */ +int viortc_read_alarm(struct viortc_dev *viortc, u16 vio_clk_id, + u64 *alarm_time, bool *enabled) +{ + VIORTC_DECLARE_MSG_HDL_ONSTACK(hdl, VIRTIO_RTC_REQ_READ_ALARM, + struct virtio_rtc_req_read_alarm, + struct virtio_rtc_resp_read_alarm); + u8 flags; + int ret; + + ret = VIORTC_MSG_INIT(hdl, viortc); + if (ret) + return ret; + + VIORTC_MSG_WRITE(hdl, clock_id, &vio_clk_id); + + ret = viortc_msg_xfer(&viortc->vqs[VIORTC_REQUESTQ], VIORTC_MSG(hdl), + 0); + if (ret) { + dev_dbg(&viortc->vdev->dev, "%s: xfer returned %d\n", __func__, + ret); + goto out_release; + } + + VIORTC_MSG_READ(hdl, alarm_time, alarm_time); + VIORTC_MSG_READ(hdl, flags, &flags); + + *enabled = !!(flags & VIRTIO_RTC_FLAG_ALARM_ENABLED); + +out_release: + viortc_msg_release(VIORTC_MSG(hdl)); + + return ret; +} + +/** + * viortc_set_alarm() - VIRTIO_RTC_REQ_SET_ALARM wrapper + * @viortc: device data + * @vio_clk_id: virtio_rtc clock id + * @alarm_time: alarm time in ns + * @alarm_enable: enable or disable alarm + * + * Context: Process context. + * Return: Zero on success, negative error code otherwise. + */ +int viortc_set_alarm(struct viortc_dev *viortc, u16 vio_clk_id, u64 alarm_time, + bool alarm_enable) +{ + VIORTC_DECLARE_MSG_HDL_ONSTACK(hdl, VIRTIO_RTC_REQ_SET_ALARM, + struct virtio_rtc_req_set_alarm, + struct virtio_rtc_resp_set_alarm); + u8 flags = 0; + int ret; + + ret = VIORTC_MSG_INIT(hdl, viortc); + if (ret) + return ret; + + if (alarm_enable) + flags |= VIRTIO_RTC_FLAG_ALARM_ENABLED; + + VIORTC_MSG_WRITE(hdl, clock_id, &vio_clk_id); + VIORTC_MSG_WRITE(hdl, alarm_time, &alarm_time); + VIORTC_MSG_WRITE(hdl, flags, &flags); + + ret = viortc_msg_xfer(&viortc->vqs[VIORTC_REQUESTQ], VIORTC_MSG(hdl), + 0); + if (ret) { + dev_dbg(&viortc->vdev->dev, "%s: xfer returned %d\n", __func__, + ret); + goto out_release; + } + +out_release: + viortc_msg_release(VIORTC_MSG(hdl)); + + return ret; +} + +/** + * viortc_set_alarm_enabled() - VIRTIO_RTC_REQ_SET_ALARM_ENABLED wrapper + * @viortc: device data + * @vio_clk_id: virtio_rtc clock id + * @alarm_enable: enable or disable alarm + * + * Context: Process context. + * Return: Zero on success, negative error code otherwise. + */ +int viortc_set_alarm_enabled(struct viortc_dev *viortc, u16 vio_clk_id, + bool alarm_enable) +{ + VIORTC_DECLARE_MSG_HDL_ONSTACK(hdl, VIRTIO_RTC_REQ_SET_ALARM_ENABLED, + struct virtio_rtc_req_set_alarm_enabled, + struct virtio_rtc_resp_set_alarm_enabled); + u8 flags = 0; + int ret; + + ret = VIORTC_MSG_INIT(hdl, viortc); + if (ret) + return ret; + + if (alarm_enable) + flags |= VIRTIO_RTC_FLAG_ALARM_ENABLED; + + VIORTC_MSG_WRITE(hdl, clock_id, &vio_clk_id); + VIORTC_MSG_WRITE(hdl, flags, &flags); + + ret = viortc_msg_xfer(&viortc->vqs[VIORTC_REQUESTQ], VIORTC_MSG(hdl), + 0); + if (ret) { + dev_dbg(&viortc->vdev->dev, "%s: xfer returned %d\n", __func__, + ret); + goto out_release; + } + +out_release: + viortc_msg_release(VIORTC_MSG(hdl)); + + return ret; +} + +/* + * init, deinit + */ + +/** + * viortc_init_rtc_class_clock() - init and register a RTC class device + * @viortc: device data + * @vio_clk_id: virtio_rtc clock id + * @clock_type: virtio_rtc clock type + * @flags: struct virtio_rtc_resp_clock_cap.flags + * + * The clock must be a UTC-like clock. + * + * Context: Process context. + * Return: Positive if registered, zero if not supported by configuration, + * negative error code otherwise. + */ +static int viortc_init_rtc_class_clock(struct viortc_dev *viortc, + u16 vio_clk_id, u8 clock_type, u8 flags) +{ + struct virtio_device *vdev = viortc->vdev; + struct viortc_class *viortc_class; + struct device *dev = &vdev->dev; + bool have_alarm; + + if (clock_type != VIRTIO_RTC_CLOCK_UTC_SMEARED) { + dev_info(dev, + "not creating RTC class device for clock %d, which may step on leap seconds\n", + vio_clk_id); + return 0; + } + + if (viortc->viortc_class) { + dev_warn_once(dev, + "multiple UTC-like clocks are present, but creating only one RTC class device\n"); + return 0; + } + + have_alarm = viortc_alarms_supported(vdev) && + !!(flags & VIRTIO_RTC_FLAG_ALARM_CAP); + + viortc_class = viortc_class_init(viortc, vio_clk_id, have_alarm, dev); + if (IS_ERR(viortc_class)) + return PTR_ERR(viortc_class); + + viortc->viortc_class = viortc_class; + + if (have_alarm) + devm_device_init_wakeup(dev); + + return viortc_class_register(viortc_class) ?: 1; +} + +/** + * viortc_init_ptp_clock() - init and register PTP clock + * @viortc: device data + * @vio_clk_id: virtio_rtc clock id + * @clock_type: virtio_rtc clock type + * @leap_second_smearing: virtio_rtc leap second smearing + * + * Context: Process context. + * Return: Positive if registered, zero if not supported by configuration, + * negative error code otherwise. + */ +static int viortc_init_ptp_clock(struct viortc_dev *viortc, u16 vio_clk_id, + u8 clock_type, u8 leap_second_smearing) +{ + struct device *dev = &viortc->vdev->dev; + char ptp_clock_name[PTP_CLOCK_NAME_LEN]; + struct viortc_ptp_clock *vio_ptp; + + snprintf(ptp_clock_name, PTP_CLOCK_NAME_LEN, + "Virtio PTP type %hhu/variant %hhu", clock_type, + leap_second_smearing); + + vio_ptp = viortc_ptp_register(viortc, dev, vio_clk_id, ptp_clock_name); + if (IS_ERR(vio_ptp)) { + dev_err(dev, "failed to register PTP clock '%s'\n", + ptp_clock_name); + return PTR_ERR(vio_ptp); + } + + viortc->clocks_to_unregister[vio_clk_id] = vio_ptp; + + return !!vio_ptp; +} + +/** + * viortc_init_clock() - init local representation of virtio_rtc clock + * @viortc: device data + * @vio_clk_id: virtio_rtc clock id + * + * Initializes PHC and/or RTC class device to represent virtio_rtc clock. + * + * Context: Process context. + * Return: Zero on success, negative error code otherwise. + */ +static int viortc_init_clock(struct viortc_dev *viortc, u16 vio_clk_id) +{ + u8 clock_type, leap_second_smearing, flags; + bool is_exposed = false; + int ret; + + ret = viortc_clock_cap(viortc, vio_clk_id, &clock_type, + &leap_second_smearing, &flags); + if (ret) + return ret; + + if (IS_ENABLED(CONFIG_VIRTIO_RTC_CLASS) && + (clock_type == VIRTIO_RTC_CLOCK_UTC || + clock_type == VIRTIO_RTC_CLOCK_UTC_SMEARED || + clock_type == VIRTIO_RTC_CLOCK_UTC_MAYBE_SMEARED)) { + ret = viortc_init_rtc_class_clock(viortc, vio_clk_id, + clock_type, flags); + if (ret < 0) + return ret; + if (ret > 0) + is_exposed = true; + } + + if (IS_ENABLED(CONFIG_VIRTIO_RTC_PTP)) { + ret = viortc_init_ptp_clock(viortc, vio_clk_id, clock_type, + leap_second_smearing); + if (ret < 0) + return ret; + if (ret > 0) + is_exposed = true; + } + + if (!is_exposed) + dev_warn(&viortc->vdev->dev, + "cannot expose clock %d (type %d, variant %d) to userspace\n", + vio_clk_id, clock_type, leap_second_smearing); + + return 0; +} + +/** + * viortc_clocks_deinit() - unregister PHCs, stop RTC ops + * @viortc: device data + */ +static void viortc_clocks_deinit(struct viortc_dev *viortc) +{ + struct viortc_ptp_clock *vio_ptp; + unsigned int i; + + for (i = 0; i < viortc->num_clocks; i++) { + vio_ptp = viortc->clocks_to_unregister[i]; + + if (!vio_ptp) + continue; + + viortc->clocks_to_unregister[i] = NULL; + + WARN_ON(viortc_ptp_unregister(vio_ptp, &viortc->vdev->dev)); + } + + if (viortc->viortc_class) + viortc_class_stop(viortc->viortc_class); +} + +/** + * viortc_clocks_init() - init local representations of virtio_rtc clocks + * @viortc: device data + * + * Context: Process context. + * Return: Zero on success, negative error code otherwise. + */ +static int viortc_clocks_init(struct viortc_dev *viortc) +{ + u16 num_clocks; + unsigned int i; + int ret; + + ret = viortc_cfg(viortc, &num_clocks); + if (ret) + return ret; + + if (num_clocks < 1) { + dev_err(&viortc->vdev->dev, "device reported 0 clocks\n"); + return -ENODEV; + } + + viortc->num_clocks = num_clocks; + + viortc->clocks_to_unregister = + devm_kcalloc(&viortc->vdev->dev, num_clocks, + sizeof(*viortc->clocks_to_unregister), GFP_KERNEL); + if (!viortc->clocks_to_unregister) + return -ENOMEM; + + for (i = 0; i < num_clocks; i++) { + ret = viortc_init_clock(viortc, i); + if (ret) + goto err_deinit_clocks; + } + + return 0; + +err_deinit_clocks: + viortc_clocks_deinit(viortc); + + return ret; +} + +/** + * viortc_populate_vq() - populate alarmq with device-writable buffers + * @viortc: device data + * @viortc_vq: device specific data for virtqueue + * @buf_cap: device-writable buffer size in bytes + * @lock: lock queue during accesses + * + * Populates the alarmq with pre-allocated buffers. + * + * The caller is responsible for kicking the device. + * + * Context: Process context. + * Return: Zero on success, negative error code otherwise. + */ +static int viortc_populate_vq(struct viortc_dev *viortc, + struct viortc_vq *viortc_vq, u32 buf_cap, + bool lock) +{ + unsigned int num_elems, i; + struct virtqueue *vq; + unsigned long flags; + void *buf; + int ret; + + num_elems = viortc->num_alarmq_bufs; + vq = viortc_vq->vq; + + for (i = 0; i < num_elems; i++) { + buf = viortc->alarmq_bufs[i]; + + if (lock) { + spin_lock_irqsave(&viortc_vq->lock, flags); + + ret = viortc_feed_vq(viortc, vq, buf, buf_cap, buf); + + spin_unlock_irqrestore(&viortc_vq->lock, flags); + } else { + ret = viortc_feed_vq(viortc, vq, buf, buf_cap, buf); + } + + if (ret) + return ret; + } + + return 0; +} + +/** + * viortc_alloc_vq_bufs() - allocate alarmq buffers + * @viortc: device data + * @num_elems: # of buffers + * @buf_cap: per-buffer device-writable bytes + * + * Context: Process context. + * Return: Zero on success, negative error code otherwise. + */ +static int viortc_alloc_vq_bufs(struct viortc_dev *viortc, + unsigned int num_elems, u32 buf_cap) +{ + struct device *dev = &viortc->vdev->dev; + void **buf_list; + unsigned int i; + void *buf; + + buf_list = devm_kcalloc(dev, num_elems, sizeof(*buf_list), GFP_KERNEL); + if (!buf_list) + return -ENOMEM; + + viortc->alarmq_bufs = buf_list; + viortc->num_alarmq_bufs = num_elems; + + for (i = 0; i < num_elems; i++) { + buf = devm_kzalloc(dev, buf_cap, GFP_KERNEL); + if (!buf) + return -ENOMEM; + + buf_list[i] = buf; + } + + return 0; +} + +/** + * viortc_init_vqs() - init virtqueues + * @viortc: device data + * + * Inits virtqueues and associated data. + * + * Context: Process context. + * Return: Zero on success, negative error code otherwise. + */ +static int viortc_init_vqs(struct viortc_dev *viortc) +{ + struct virtqueue *vqs[VIORTC_MAX_NR_QUEUES]; + struct virtqueue_info vqs_info[] = { + { "requestq", viortc_cb_requestq }, + { "alarmq", viortc_cb_alarmq }, + }; + struct virtio_device *vdev = viortc->vdev; + unsigned int num_elems; + int nr_queues, ret; + bool have_alarms; + + have_alarms = viortc_alarms_supported(vdev); + + if (have_alarms) + nr_queues = VIORTC_ALARMQ + 1; + else + nr_queues = VIORTC_REQUESTQ + 1; + + ret = virtio_find_vqs(vdev, nr_queues, vqs, vqs_info, NULL); + if (ret) + return ret; + + viortc->vqs[VIORTC_REQUESTQ].vq = vqs[VIORTC_REQUESTQ]; + spin_lock_init(&viortc->vqs[VIORTC_REQUESTQ].lock); + + if (have_alarms) { + viortc->vqs[VIORTC_ALARMQ].vq = vqs[VIORTC_ALARMQ]; + spin_lock_init(&viortc->vqs[VIORTC_ALARMQ].lock); + + num_elems = virtqueue_get_vring_size(vqs[VIORTC_ALARMQ]); + if (num_elems == 0) + return -ENOSPC; + + if (!viortc->alarmq_bufs) { + ret = viortc_alloc_vq_bufs(viortc, num_elems, + VIORTC_ALARMQ_BUF_CAP); + if (ret) + return ret; + } else { + viortc->num_alarmq_bufs = + min(num_elems, viortc->num_alarmq_bufs); + } + } + + return 0; +} + +/** + * viortc_probe() - probe a virtio_rtc virtio device + * @vdev: virtio device + * + * Context: Process context. + * Return: Zero on success, negative error code otherwise. + */ +static int viortc_probe(struct virtio_device *vdev) +{ + struct viortc_vq *alarm_viortc_vq; + struct virtqueue *alarm_vq; + struct viortc_dev *viortc; + unsigned long flags; + bool notify; + int ret; + + viortc = devm_kzalloc(&vdev->dev, sizeof(*viortc), GFP_KERNEL); + if (!viortc) + return -ENOMEM; + + vdev->priv = viortc; + viortc->vdev = vdev; + + ret = viortc_init_vqs(viortc); + if (ret) + return ret; + + virtio_device_ready(vdev); + + ret = viortc_clocks_init(viortc); + if (ret) + goto err_reset_vdev; + + if (viortc_alarms_supported(vdev)) { + alarm_viortc_vq = &viortc->vqs[VIORTC_ALARMQ]; + alarm_vq = alarm_viortc_vq->vq; + + ret = viortc_populate_vq(viortc, alarm_viortc_vq, + VIORTC_ALARMQ_BUF_CAP, true); + if (ret) + goto err_deinit_clocks; + + spin_lock_irqsave(&alarm_viortc_vq->lock, flags); + notify = virtqueue_kick_prepare(alarm_vq); + spin_unlock_irqrestore(&alarm_viortc_vq->lock, flags); + + if (notify && !virtqueue_notify(alarm_vq)) { + ret = -EIO; + goto err_deinit_clocks; + } + } + + return 0; + +err_deinit_clocks: + viortc_clocks_deinit(viortc); + +err_reset_vdev: + virtio_reset_device(vdev); + vdev->config->del_vqs(vdev); + + return ret; +} + +/** + * viortc_remove() - remove a virtio_rtc virtio device + * @vdev: virtio device + */ +static void viortc_remove(struct virtio_device *vdev) +{ + struct viortc_dev *viortc = vdev->priv; + + viortc_clocks_deinit(viortc); + + virtio_reset_device(vdev); + vdev->config->del_vqs(vdev); +} + +static int viortc_freeze(struct virtio_device *dev) +{ + /* + * Do not reset the device, so that the device may still wake up the + * system through an alarmq notification. + */ + + return 0; +} + +static int viortc_restore(struct virtio_device *dev) +{ + struct viortc_dev *viortc = dev->priv; + struct viortc_vq *alarm_viortc_vq; + struct virtqueue *alarm_vq; + bool notify = false; + int ret; + + ret = viortc_init_vqs(viortc); + if (ret) + return ret; + + alarm_viortc_vq = &viortc->vqs[VIORTC_ALARMQ]; + alarm_vq = alarm_viortc_vq->vq; + + if (viortc_alarms_supported(dev)) { + ret = viortc_populate_vq(viortc, alarm_viortc_vq, + VIORTC_ALARMQ_BUF_CAP, false); + if (ret) + return ret; + + notify = virtqueue_kick_prepare(alarm_vq); + } + + virtio_device_ready(dev); + + if (notify && !virtqueue_notify(alarm_vq)) + ret = -EIO; + + return ret; +} + +static unsigned int features[] = { +#if IS_ENABLED(CONFIG_VIRTIO_RTC_CLASS) + VIRTIO_RTC_F_ALARM, +#endif +}; + +static struct virtio_device_id id_table[] = { + { VIRTIO_ID_CLOCK, VIRTIO_DEV_ANY_ID }, + { 0 }, +}; +MODULE_DEVICE_TABLE(virtio, id_table); + +static struct virtio_driver virtio_rtc_drv = { + .driver.name = KBUILD_MODNAME, + .feature_table = features, + .feature_table_size = ARRAY_SIZE(features), + .id_table = id_table, + .probe = viortc_probe, + .remove = viortc_remove, + .freeze = pm_sleep_ptr(viortc_freeze), + .restore = pm_sleep_ptr(viortc_restore), +}; + +module_virtio_driver(virtio_rtc_drv); + +MODULE_DESCRIPTION("Virtio RTC driver"); +MODULE_AUTHOR("Qualcomm Innovation Center, Inc."); +MODULE_LICENSE("GPL"); diff --git a/drivers/virtio/virtio_rtc_internal.h b/drivers/virtio/virtio_rtc_internal.h new file mode 100644 index 000000000000..296afee6719b --- /dev/null +++ b/drivers/virtio/virtio_rtc_internal.h @@ -0,0 +1,122 @@ +/* SPDX-License-Identifier: GPL-2.0-or-later */ +/* + * virtio_rtc internal interfaces + * + * Copyright (C) 2022-2023 OpenSynergy GmbH + * Copyright (c) 2024 Qualcomm Innovation Center, Inc. All rights reserved. + */ + +#ifndef _VIRTIO_RTC_INTERNAL_H_ +#define _VIRTIO_RTC_INTERNAL_H_ + +#include <linux/device.h> +#include <linux/err.h> +#include <linux/ptp_clock_kernel.h> +#include <linux/types.h> + +/* driver core IFs */ + +struct viortc_dev; + +int viortc_read(struct viortc_dev *viortc, u16 vio_clk_id, u64 *reading); +int viortc_read_cross(struct viortc_dev *viortc, u16 vio_clk_id, u8 hw_counter, + u64 *reading, u64 *cycles); +int viortc_cross_cap(struct viortc_dev *viortc, u16 vio_clk_id, u8 hw_counter, + bool *supported); +int viortc_read_alarm(struct viortc_dev *viortc, u16 vio_clk_id, + u64 *alarm_time, bool *enabled); +int viortc_set_alarm(struct viortc_dev *viortc, u16 vio_clk_id, u64 alarm_time, + bool alarm_enable); +int viortc_set_alarm_enabled(struct viortc_dev *viortc, u16 vio_clk_id, + bool alarm_enable); + +struct viortc_class; + +struct viortc_class *viortc_class_from_dev(struct device *dev); + +/* PTP IFs */ + +struct viortc_ptp_clock; + +#if IS_ENABLED(CONFIG_VIRTIO_RTC_PTP) + +struct viortc_ptp_clock *viortc_ptp_register(struct viortc_dev *viortc, + struct device *parent_dev, + u16 vio_clk_id, + const char *ptp_clock_name); +int viortc_ptp_unregister(struct viortc_ptp_clock *vio_ptp, + struct device *parent_dev); + +#else + +static inline struct viortc_ptp_clock * +viortc_ptp_register(struct viortc_dev *viortc, struct device *parent_dev, + u16 vio_clk_id, const char *ptp_clock_name) +{ + return NULL; +} + +static inline int viortc_ptp_unregister(struct viortc_ptp_clock *vio_ptp, + struct device *parent_dev) +{ + return -ENODEV; +} + +#endif + +/* HW counter IFs */ + +/** + * viortc_hw_xtstamp_params() - get HW-specific xtstamp params + * @hw_counter: virtio_rtc HW counter type + * @cs_id: clocksource id corresponding to hw_counter + * + * Gets the HW-specific xtstamp params. Returns an error if the driver cannot + * support xtstamp. + * + * Context: Process context. + * Return: Zero on success, negative error code otherwise. + */ +int viortc_hw_xtstamp_params(u8 *hw_counter, enum clocksource_ids *cs_id); + +/* RTC class IFs */ + +#if IS_ENABLED(CONFIG_VIRTIO_RTC_CLASS) + +void viortc_class_alarm(struct viortc_class *viortc_class, u16 vio_clk_id); + +void viortc_class_stop(struct viortc_class *viortc_class); + +int viortc_class_register(struct viortc_class *viortc_class); + +struct viortc_class *viortc_class_init(struct viortc_dev *viortc, + u16 vio_clk_id, bool have_alarm, + struct device *parent_dev); + +#else /* CONFIG_VIRTIO_RTC_CLASS */ + +static inline void viortc_class_alarm(struct viortc_class *viortc_class, + u16 vio_clk_id) +{ +} + +static inline void viortc_class_stop(struct viortc_class *viortc_class) +{ +} + +static inline int viortc_class_register(struct viortc_class *viortc_class) +{ + return -ENODEV; +} + +static inline struct viortc_class *viortc_class_init(struct viortc_dev *viortc, + u16 vio_clk_id, + bool have_alarm, + struct device *parent_dev) +{ + return ERR_PTR(-ENODEV); +} + +#endif /* CONFIG_VIRTIO_RTC_CLASS */ + +#endif /* _VIRTIO_RTC_INTERNAL_H_ */ diff --git a/drivers/virtio/virtio_rtc_ptp.c b/drivers/virtio/virtio_rtc_ptp.c new file mode 100644 index 000000000000..f84599950cd4 --- /dev/null +++ b/drivers/virtio/virtio_rtc_ptp.c @@ -0,0 +1,347 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * Expose virtio_rtc clocks as PTP clocks. + * + * Copyright (C) 2022-2023 OpenSynergy GmbH + * Copyright (c) 2024 Qualcomm Innovation Center, Inc. All rights reserved. + * + * Derived from ptp_kvm_common.c, virtual PTP 1588 clock for use with KVM + * guests. + * + * Copyright (C) 2017 Red Hat Inc. + */ + +#include <linux/device.h> +#include <linux/err.h> +#include <linux/ptp_clock_kernel.h> + +#include <uapi/linux/virtio_rtc.h> + +#include "virtio_rtc_internal.h" + +/** + * struct viortc_ptp_clock - PTP clock abstraction + * @ptp_clock: PTP clock handle for unregistering + * @viortc: virtio_rtc device data + * @ptp_info: PTP clock description + * @vio_clk_id: virtio_rtc clock id + * @have_cross: device supports crosststamp with available HW counter + */ +struct viortc_ptp_clock { + struct ptp_clock *ptp_clock; + struct viortc_dev *viortc; + struct ptp_clock_info ptp_info; + u16 vio_clk_id; + bool have_cross; +}; + +/** + * struct viortc_ptp_cross_ctx - context for get_device_system_crosststamp() + * @device_time: device clock reading + * @system_counterval: HW counter value at device_time + * + * Provides the already obtained crosststamp to get_device_system_crosststamp(). + */ +struct viortc_ptp_cross_ctx { + ktime_t device_time; + struct system_counterval_t system_counterval; +}; + +/* Weak function in case get_device_system_crosststamp() is not supported */ +int __weak viortc_hw_xtstamp_params(u8 *hw_counter, enum clocksource_ids *cs_id) +{ + return -EOPNOTSUPP; +} + +/** + * viortc_ptp_get_time_fn() - callback for get_device_system_crosststamp() + * @device_time: device clock reading + * @system_counterval: HW counter value at device_time + * @ctx: context with already obtained crosststamp + * + * Return: zero (success). + */ +static int viortc_ptp_get_time_fn(ktime_t *device_time, + struct system_counterval_t *system_counterval, + void *ctx) +{ + struct viortc_ptp_cross_ctx *vio_ctx = ctx; + + *device_time = vio_ctx->device_time; + *system_counterval = vio_ctx->system_counterval; + + return 0; +} + +/** + * viortc_ptp_do_xtstamp() - get crosststamp from device + * @vio_ptp: virtio_rtc PTP clock + * @hw_counter: virtio_rtc HW counter type + * @cs_id: clocksource id corresponding to hw_counter + * @ctx: context for get_device_system_crosststamp() + * + * Reads HW-specific crosststamp from device. + * + * Context: Process context. + * Return: Zero on success, negative error code otherwise. + */ +static int viortc_ptp_do_xtstamp(struct viortc_ptp_clock *vio_ptp, + u8 hw_counter, enum clocksource_ids cs_id, + struct viortc_ptp_cross_ctx *ctx) +{ + u64 max_ns, ns; + int ret; + + ctx->system_counterval.cs_id = cs_id; + + ret = viortc_read_cross(vio_ptp->viortc, vio_ptp->vio_clk_id, + hw_counter, &ns, + &ctx->system_counterval.cycles); + if (ret) + return ret; + + max_ns = (u64)ktime_to_ns(KTIME_MAX); + if (ns > max_ns) + return -EINVAL; + + ctx->device_time = ns_to_ktime(ns); + + return 0; +} + +/* + * PTP clock operations + */ + +/** + * viortc_ptp_getcrosststamp() - PTP clock getcrosststamp op + * @ptp: PTP clock info + * @xtstamp: crosststamp + * + * Context: Process context. + * Return: Zero on success, negative error code otherwise. + */ +static int viortc_ptp_getcrosststamp(struct ptp_clock_info *ptp, + struct system_device_crosststamp *xtstamp) +{ + struct viortc_ptp_clock *vio_ptp = + container_of(ptp, struct viortc_ptp_clock, ptp_info); + struct system_time_snapshot history_begin; + struct viortc_ptp_cross_ctx ctx; + enum clocksource_ids cs_id; + u8 hw_counter; + int ret; + + if (!vio_ptp->have_cross) + return -EOPNOTSUPP; + + ret = viortc_hw_xtstamp_params(&hw_counter, &cs_id); + if (ret) + return ret; + + ktime_get_snapshot(&history_begin); + if (history_begin.cs_id != cs_id) + return -EOPNOTSUPP; + + /* + * Getting the timestamp can take many milliseconds with a slow Virtio + * device. This is too long for viortc_ptp_get_time_fn() passed to + * get_device_system_crosststamp(), which has to usually return before + * the timekeeper seqcount increases (every tick or so). + * + * So, get the actual cross-timestamp first. + */ + ret = viortc_ptp_do_xtstamp(vio_ptp, hw_counter, cs_id, &ctx); + if (ret) + return ret; + + ret = get_device_system_crosststamp(viortc_ptp_get_time_fn, &ctx, + &history_begin, xtstamp); + if (ret) + pr_debug("%s: get_device_system_crosststamp() returned %d\n", + __func__, ret); + + return ret; +} + +/* viortc_ptp_adjfine() - unsupported PTP clock adjfine op */ +static int viortc_ptp_adjfine(struct ptp_clock_info *ptp, long scaled_ppm) +{ + return -EOPNOTSUPP; +} + +/* viortc_ptp_adjtime() - unsupported PTP clock adjtime op */ +static int viortc_ptp_adjtime(struct ptp_clock_info *ptp, s64 delta) +{ + return -EOPNOTSUPP; +} + +/* viortc_ptp_settime64() - unsupported PTP clock settime64 op */ +static int viortc_ptp_settime64(struct ptp_clock_info *ptp, + const struct timespec64 *ts) +{ + return -EOPNOTSUPP; +} + +/* + * viortc_ptp_gettimex64() - PTP clock gettimex64 op + * + * Context: Process context. + */ +static int viortc_ptp_gettimex64(struct ptp_clock_info *ptp, + struct timespec64 *ts, + struct ptp_system_timestamp *sts) +{ + struct viortc_ptp_clock *vio_ptp = + container_of(ptp, struct viortc_ptp_clock, ptp_info); + int ret; + u64 ns; + + ptp_read_system_prets(sts); + ret = viortc_read(vio_ptp->viortc, vio_ptp->vio_clk_id, &ns); + ptp_read_system_postts(sts); + + if (ret) + return ret; + + if (ns > (u64)S64_MAX) + return -EINVAL; + + *ts = ns_to_timespec64((s64)ns); + + return 0; +} + +/* viortc_ptp_enable() - unsupported PTP clock enable op */ +static int viortc_ptp_enable(struct ptp_clock_info *ptp, + struct ptp_clock_request *rq, int on) +{ + return -EOPNOTSUPP; +} + +/* + * viortc_ptp_info_template - ptp_clock_info template + * + * The .name member will be set for individual virtio_rtc PTP clocks. + * + * The .getcrosststamp member will be cleared for PTP clocks not supporting + * crosststamp. + */ +static const struct ptp_clock_info viortc_ptp_info_template = { + .owner = THIS_MODULE, + /* .name is set according to clock type */ + .adjfine = viortc_ptp_adjfine, + .adjtime = viortc_ptp_adjtime, + .gettimex64 = viortc_ptp_gettimex64, + .settime64 = viortc_ptp_settime64, + .enable = viortc_ptp_enable, + .getcrosststamp = viortc_ptp_getcrosststamp, +}; + +/** + * viortc_ptp_unregister() - PTP clock unregistering wrapper + * @vio_ptp: virtio_rtc PTP clock + * @parent_dev: parent device of PTP clock + * + * Return: Zero on success, negative error code otherwise. + */ +int viortc_ptp_unregister(struct viortc_ptp_clock *vio_ptp, + struct device *parent_dev) +{ + int ret = ptp_clock_unregister(vio_ptp->ptp_clock); + + if (!ret) + devm_kfree(parent_dev, vio_ptp); + + return ret; +} + +/** + * viortc_ptp_get_cross_cap() - get xtstamp support info from device + * @viortc: virtio_rtc device data + * @vio_ptp: virtio_rtc PTP clock abstraction + * + * Context: Process context. + * Return: Zero on success, negative error code otherwise. + */ +static int viortc_ptp_get_cross_cap(struct viortc_dev *viortc, + struct viortc_ptp_clock *vio_ptp) +{ + enum clocksource_ids cs_id; + bool xtstamp_supported; + u8 hw_counter; + int ret; + + ret = viortc_hw_xtstamp_params(&hw_counter, &cs_id); + if (ret) { + vio_ptp->have_cross = false; + return 0; + } + + ret = viortc_cross_cap(viortc, vio_ptp->vio_clk_id, hw_counter, + &xtstamp_supported); + if (ret) + return ret; + + vio_ptp->have_cross = xtstamp_supported; + + return 0; +} + +/** + * viortc_ptp_register() - prepare and register PTP clock + * @viortc: virtio_rtc device data + * @parent_dev: parent device for PTP clock + * @vio_clk_id: id of virtio_rtc clock which backs PTP clock + * @ptp_clock_name: PTP clock name + * + * Context: Process context. + * Return: Pointer on success, ERR_PTR() otherwise; NULL if PTP clock support + * not available. + */ +struct viortc_ptp_clock *viortc_ptp_register(struct viortc_dev *viortc, + struct device *parent_dev, + u16 vio_clk_id, + const char *ptp_clock_name) +{ + struct viortc_ptp_clock *vio_ptp; + struct ptp_clock *ptp_clock; + ssize_t len; + int ret; + + vio_ptp = devm_kzalloc(parent_dev, sizeof(*vio_ptp), GFP_KERNEL); + if (!vio_ptp) + return ERR_PTR(-ENOMEM); + + vio_ptp->viortc = viortc; + vio_ptp->vio_clk_id = vio_clk_id; + vio_ptp->ptp_info = viortc_ptp_info_template; + len = strscpy(vio_ptp->ptp_info.name, ptp_clock_name, + sizeof(vio_ptp->ptp_info.name)); + if (len < 0) { + ret = len; + goto err_free_dev; + } + + ret = viortc_ptp_get_cross_cap(viortc, vio_ptp); + if (ret) + goto err_free_dev; + + if (!vio_ptp->have_cross) + vio_ptp->ptp_info.getcrosststamp = NULL; + + ptp_clock = ptp_clock_register(&vio_ptp->ptp_info, parent_dev); + if (IS_ERR(ptp_clock)) + goto err_on_register; + + vio_ptp->ptp_clock = ptp_clock; + + return vio_ptp; + +err_on_register: + ret = PTR_ERR(ptp_clock); + +err_free_dev: + devm_kfree(parent_dev, vio_ptp); + return ERR_PTR(ret); +} diff --git a/drivers/virtio/virtio_vdpa.c b/drivers/virtio/virtio_vdpa.c new file mode 100644 index 000000000000..0a801f67b599 --- /dev/null +++ b/drivers/virtio/virtio_vdpa.c @@ -0,0 +1,518 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * VIRTIO based driver for vDPA device + * + * Copyright (c) 2020, Red Hat. All rights reserved. + * Author: Jason Wang <jasowang@redhat.com> + * + */ + +#include <linux/init.h> +#include <linux/module.h> +#include <linux/device.h> +#include <linux/kernel.h> +#include <linux/slab.h> +#include <linux/uuid.h> +#include <linux/group_cpus.h> +#include <linux/virtio.h> +#include <linux/vdpa.h> +#include <linux/virtio_config.h> +#include <linux/virtio_ring.h> + +#define MOD_VERSION "0.1" +#define MOD_AUTHOR "Jason Wang <jasowang@redhat.com>" +#define MOD_DESC "vDPA bus driver for virtio devices" +#define MOD_LICENSE "GPL v2" + +struct virtio_vdpa_device { + struct virtio_device vdev; + struct vdpa_device *vdpa; + u64 features; +}; + +static inline struct virtio_vdpa_device * +to_virtio_vdpa_device(struct virtio_device *dev) +{ + return container_of(dev, struct virtio_vdpa_device, vdev); +} + +static struct vdpa_device *vd_get_vdpa(struct virtio_device *vdev) +{ + return to_virtio_vdpa_device(vdev)->vdpa; +} + +static void virtio_vdpa_get(struct virtio_device *vdev, unsigned int offset, + void *buf, unsigned int len) +{ + struct vdpa_device *vdpa = vd_get_vdpa(vdev); + + vdpa_get_config(vdpa, offset, buf, len); +} + +static void virtio_vdpa_set(struct virtio_device *vdev, unsigned int offset, + const void *buf, unsigned int len) +{ + struct vdpa_device *vdpa = vd_get_vdpa(vdev); + + vdpa_set_config(vdpa, offset, buf, len); +} + +static u32 virtio_vdpa_generation(struct virtio_device *vdev) +{ + struct vdpa_device *vdpa = vd_get_vdpa(vdev); + const struct vdpa_config_ops *ops = vdpa->config; + + if (ops->get_generation) + return ops->get_generation(vdpa); + + return 0; +} + +static u8 virtio_vdpa_get_status(struct virtio_device *vdev) +{ + struct vdpa_device *vdpa = vd_get_vdpa(vdev); + const struct vdpa_config_ops *ops = vdpa->config; + + return ops->get_status(vdpa); +} + +static void virtio_vdpa_set_status(struct virtio_device *vdev, u8 status) +{ + struct vdpa_device *vdpa = vd_get_vdpa(vdev); + + vdpa_set_status(vdpa, status); +} + +static void virtio_vdpa_reset(struct virtio_device *vdev) +{ + struct vdpa_device *vdpa = vd_get_vdpa(vdev); + + vdpa_reset(vdpa, 0); +} + +static bool virtio_vdpa_notify(struct virtqueue *vq) +{ + struct vdpa_device *vdpa = vd_get_vdpa(vq->vdev); + const struct vdpa_config_ops *ops = vdpa->config; + + ops->kick_vq(vdpa, vq->index); + + return true; +} + +static bool virtio_vdpa_notify_with_data(struct virtqueue *vq) +{ + struct vdpa_device *vdpa = vd_get_vdpa(vq->vdev); + const struct vdpa_config_ops *ops = vdpa->config; + u32 data = vring_notification_data(vq); + + ops->kick_vq_with_data(vdpa, data); + + return true; +} + +static irqreturn_t virtio_vdpa_config_cb(void *private) +{ + struct virtio_vdpa_device *vd_dev = private; + + virtio_config_changed(&vd_dev->vdev); + + return IRQ_HANDLED; +} + +static irqreturn_t virtio_vdpa_virtqueue_cb(void *private) +{ + struct virtqueue *vq = private; + + return vring_interrupt(0, vq); +} + +static struct virtqueue * +virtio_vdpa_setup_vq(struct virtio_device *vdev, unsigned int index, + void (*callback)(struct virtqueue *vq), + const char *name, bool ctx) +{ + struct vdpa_device *vdpa = vd_get_vdpa(vdev); + const struct vdpa_config_ops *ops = vdpa->config; + bool (*notify)(struct virtqueue *vq) = virtio_vdpa_notify; + struct vdpa_callback cb; + struct virtqueue *vq; + u64 desc_addr, driver_addr, device_addr; + union virtio_map map = {0}; + /* Assume split virtqueue, switch to packed if necessary */ + struct vdpa_vq_state state = {0}; + u32 align, max_num, min_num = 1; + bool may_reduce_num = true; + int err; + + if (!name) + return NULL; + + if (index >= vdpa->nvqs) + return ERR_PTR(-ENOENT); + + /* We cannot accept VIRTIO_F_NOTIFICATION_DATA without kick_vq_with_data */ + if (__virtio_test_bit(vdev, VIRTIO_F_NOTIFICATION_DATA)) { + if (ops->kick_vq_with_data) + notify = virtio_vdpa_notify_with_data; + else + __virtio_clear_bit(vdev, VIRTIO_F_NOTIFICATION_DATA); + } + + /* Queue shouldn't already be set up. */ + if (ops->get_vq_ready(vdpa, index)) + return ERR_PTR(-ENOENT); + + if (ops->get_vq_size) + max_num = ops->get_vq_size(vdpa, index); + else + max_num = ops->get_vq_num_max(vdpa); + + if (max_num == 0) { + err = -ENOENT; + goto error_new_virtqueue; + } + + if (ops->get_vq_num_min) + min_num = ops->get_vq_num_min(vdpa); + + may_reduce_num = (max_num != min_num); + + /* Create the vring */ + align = ops->get_vq_align(vdpa); + + if (ops->get_vq_map) + map = ops->get_vq_map(vdpa, index); + else + map = vdpa_get_map(vdpa); + + vq = vring_create_virtqueue_map(index, max_num, align, vdev, + true, may_reduce_num, ctx, + notify, callback, name, map); + if (!vq) { + err = -ENOMEM; + goto error_new_virtqueue; + } + + if (index == 0) + vdev->vmap = map; + + vq->num_max = max_num; + + /* Setup virtqueue callback */ + cb.callback = callback ? virtio_vdpa_virtqueue_cb : NULL; + cb.private = vq; + cb.trigger = NULL; + ops->set_vq_cb(vdpa, index, &cb); + ops->set_vq_num(vdpa, index, virtqueue_get_vring_size(vq)); + + desc_addr = virtqueue_get_desc_addr(vq); + driver_addr = virtqueue_get_avail_addr(vq); + device_addr = virtqueue_get_used_addr(vq); + + if (ops->set_vq_address(vdpa, index, + desc_addr, driver_addr, + device_addr)) { + err = -EINVAL; + goto err_vq; + } + + /* reset virtqueue state index */ + if (virtio_has_feature(vdev, VIRTIO_F_RING_PACKED)) { + struct vdpa_vq_state_packed *s = &state.packed; + + s->last_avail_counter = 1; + s->last_avail_idx = 0; + s->last_used_counter = 1; + s->last_used_idx = 0; + } + err = ops->set_vq_state(vdpa, index, &state); + if (err) + goto err_vq; + + ops->set_vq_ready(vdpa, index, 1); + + return vq; + +err_vq: + vring_del_virtqueue(vq); +error_new_virtqueue: + ops->set_vq_ready(vdpa, index, 0); + /* VDPA driver should make sure vq is stopeed here */ + WARN_ON(ops->get_vq_ready(vdpa, index)); + return ERR_PTR(err); +} + +static void virtio_vdpa_del_vq(struct virtqueue *vq) +{ + struct virtio_vdpa_device *vd_dev = to_virtio_vdpa_device(vq->vdev); + struct vdpa_device *vdpa = vd_dev->vdpa; + const struct vdpa_config_ops *ops = vdpa->config; + unsigned int index = vq->index; + + /* Select and deactivate the queue (best effort) */ + ops->set_vq_ready(vdpa, index, 0); + + vring_del_virtqueue(vq); +} + +static void virtio_vdpa_del_vqs(struct virtio_device *vdev) +{ + struct virtqueue *vq, *n; + + list_for_each_entry_safe(vq, n, &vdev->vqs, list) + virtio_vdpa_del_vq(vq); +} + +static void default_calc_sets(struct irq_affinity *affd, unsigned int affvecs) +{ + affd->nr_sets = 1; + affd->set_size[0] = affvecs; +} + +static struct cpumask * +create_affinity_masks(unsigned int nvecs, struct irq_affinity *affd) +{ + unsigned int affvecs = 0, curvec, usedvecs, i; + struct cpumask *masks = NULL; + + if (nvecs > affd->pre_vectors + affd->post_vectors) + affvecs = nvecs - affd->pre_vectors - affd->post_vectors; + + if (!affd->calc_sets) + affd->calc_sets = default_calc_sets; + + affd->calc_sets(affd, affvecs); + + if (!affvecs) + return NULL; + + masks = kcalloc(nvecs, sizeof(*masks), GFP_KERNEL); + if (!masks) + return NULL; + + /* Fill out vectors at the beginning that don't need affinity */ + for (curvec = 0; curvec < affd->pre_vectors; curvec++) + cpumask_setall(&masks[curvec]); + + for (i = 0, usedvecs = 0; i < affd->nr_sets; i++) { + unsigned int this_vecs = affd->set_size[i]; + unsigned int nr_masks; + int j; + struct cpumask *result = group_cpus_evenly(this_vecs, &nr_masks); + + if (!result) { + kfree(masks); + return NULL; + } + + for (j = 0; j < nr_masks; j++) + cpumask_copy(&masks[curvec + j], &result[j]); + kfree(result); + + curvec += nr_masks; + usedvecs += nr_masks; + } + + /* Fill out vectors at the end that don't need affinity */ + if (usedvecs >= affvecs) + curvec = affd->pre_vectors + affvecs; + else + curvec = affd->pre_vectors + usedvecs; + for (; curvec < nvecs; curvec++) + cpumask_setall(&masks[curvec]); + + return masks; +} + +static int virtio_vdpa_find_vqs(struct virtio_device *vdev, unsigned int nvqs, + struct virtqueue *vqs[], + struct virtqueue_info vqs_info[], + struct irq_affinity *desc) +{ + struct virtio_vdpa_device *vd_dev = to_virtio_vdpa_device(vdev); + struct vdpa_device *vdpa = vd_get_vdpa(vdev); + const struct vdpa_config_ops *ops = vdpa->config; + struct cpumask *masks; + struct vdpa_callback cb; + bool has_affinity = desc && ops->set_vq_affinity; + int i, err, queue_idx = 0; + + if (has_affinity) { + masks = create_affinity_masks(nvqs, desc); + if (!masks) + return -ENOMEM; + } + + for (i = 0; i < nvqs; ++i) { + struct virtqueue_info *vqi = &vqs_info[i]; + + if (!vqi->name) { + vqs[i] = NULL; + continue; + } + + vqs[i] = virtio_vdpa_setup_vq(vdev, queue_idx++, vqi->callback, + vqi->name, vqi->ctx); + if (IS_ERR(vqs[i])) { + err = PTR_ERR(vqs[i]); + goto err_setup_vq; + } + + if (has_affinity) + ops->set_vq_affinity(vdpa, i, &masks[i]); + } + + cb.callback = virtio_vdpa_config_cb; + cb.private = vd_dev; + ops->set_config_cb(vdpa, &cb); + if (has_affinity) + kfree(masks); + + return 0; + +err_setup_vq: + virtio_vdpa_del_vqs(vdev); + if (has_affinity) + kfree(masks); + return err; +} + +static u64 virtio_vdpa_get_features(struct virtio_device *vdev) +{ + struct vdpa_device *vdpa = vd_get_vdpa(vdev); + const struct vdpa_config_ops *ops = vdpa->config; + + return ops->get_device_features(vdpa); +} + +static int virtio_vdpa_finalize_features(struct virtio_device *vdev) +{ + struct vdpa_device *vdpa = vd_get_vdpa(vdev); + + /* Give virtio_ring a chance to accept features. */ + vring_transport_features(vdev); + + return vdpa_set_features(vdpa, vdev->features); +} + +static const char *virtio_vdpa_bus_name(struct virtio_device *vdev) +{ + struct virtio_vdpa_device *vd_dev = to_virtio_vdpa_device(vdev); + struct vdpa_device *vdpa = vd_dev->vdpa; + + return dev_name(&vdpa->dev); +} + +static int virtio_vdpa_set_vq_affinity(struct virtqueue *vq, + const struct cpumask *cpu_mask) +{ + struct virtio_vdpa_device *vd_dev = to_virtio_vdpa_device(vq->vdev); + struct vdpa_device *vdpa = vd_dev->vdpa; + const struct vdpa_config_ops *ops = vdpa->config; + unsigned int index = vq->index; + + if (ops->set_vq_affinity) + return ops->set_vq_affinity(vdpa, index, cpu_mask); + + return 0; +} + +static const struct cpumask * +virtio_vdpa_get_vq_affinity(struct virtio_device *vdev, int index) +{ + struct vdpa_device *vdpa = vd_get_vdpa(vdev); + const struct vdpa_config_ops *ops = vdpa->config; + + if (ops->get_vq_affinity) + return ops->get_vq_affinity(vdpa, index); + + return NULL; +} + +static const struct virtio_config_ops virtio_vdpa_config_ops = { + .get = virtio_vdpa_get, + .set = virtio_vdpa_set, + .generation = virtio_vdpa_generation, + .get_status = virtio_vdpa_get_status, + .set_status = virtio_vdpa_set_status, + .reset = virtio_vdpa_reset, + .find_vqs = virtio_vdpa_find_vqs, + .del_vqs = virtio_vdpa_del_vqs, + .get_features = virtio_vdpa_get_features, + .finalize_features = virtio_vdpa_finalize_features, + .bus_name = virtio_vdpa_bus_name, + .set_vq_affinity = virtio_vdpa_set_vq_affinity, + .get_vq_affinity = virtio_vdpa_get_vq_affinity, +}; + +static void virtio_vdpa_release_dev(struct device *_d) +{ + struct virtio_device *vdev = + container_of(_d, struct virtio_device, dev); + struct virtio_vdpa_device *vd_dev = + container_of(vdev, struct virtio_vdpa_device, vdev); + + kfree(vd_dev); +} + +static int virtio_vdpa_probe(struct vdpa_device *vdpa) +{ + const struct vdpa_config_ops *ops = vdpa->config; + struct virtio_vdpa_device *vd_dev, *reg_dev = NULL; + int ret = -EINVAL; + + vd_dev = kzalloc(sizeof(*vd_dev), GFP_KERNEL); + if (!vd_dev) + return -ENOMEM; + + vd_dev->vdev.dev.parent = vdpa->map ? &vdpa->dev : + vdpa_get_map(vdpa).dma_dev; + vd_dev->vdev.dev.release = virtio_vdpa_release_dev; + vd_dev->vdev.config = &virtio_vdpa_config_ops; + vd_dev->vdev.map = vdpa->map; + vd_dev->vdpa = vdpa; + + vd_dev->vdev.id.device = ops->get_device_id(vdpa); + if (vd_dev->vdev.id.device == 0) + goto err; + + vd_dev->vdev.id.vendor = ops->get_vendor_id(vdpa); + ret = register_virtio_device(&vd_dev->vdev); + reg_dev = vd_dev; + if (ret) + goto err; + + vdpa_set_drvdata(vdpa, vd_dev); + + return 0; + +err: + if (reg_dev) + put_device(&vd_dev->vdev.dev); + else + kfree(vd_dev); + return ret; +} + +static void virtio_vdpa_remove(struct vdpa_device *vdpa) +{ + struct virtio_vdpa_device *vd_dev = vdpa_get_drvdata(vdpa); + + unregister_virtio_device(&vd_dev->vdev); +} + +static struct vdpa_driver virtio_vdpa_driver = { + .driver = { + .name = "virtio_vdpa", + }, + .probe = virtio_vdpa_probe, + .remove = virtio_vdpa_remove, +}; + +module_vdpa_driver(virtio_vdpa_driver); + +MODULE_VERSION(MOD_VERSION); +MODULE_LICENSE(MOD_LICENSE); +MODULE_AUTHOR(MOD_AUTHOR); +MODULE_DESCRIPTION(MOD_DESC); |