diff options
Diffstat (limited to 'drivers')
27 files changed, 2101 insertions, 518 deletions
diff --git a/drivers/gpu/drm/i915/gvt/kvmgt.c b/drivers/gpu/drm/i915/gvt/kvmgt.c index de675d799c7d..9cd9e9da60dd 100644 --- a/drivers/gpu/drm/i915/gvt/kvmgt.c +++ b/drivers/gpu/drm/i915/gvt/kvmgt.c @@ -1474,6 +1474,7 @@ static const struct vfio_device_ops intel_vgpu_dev_ops = { .bind_iommufd = vfio_iommufd_emulated_bind, .unbind_iommufd = vfio_iommufd_emulated_unbind, .attach_ioas = vfio_iommufd_emulated_attach_ioas, + .detach_ioas = vfio_iommufd_emulated_detach_ioas, }; static int intel_vgpu_probe(struct mdev_device *mdev) diff --git a/drivers/iommu/iommu-priv.h b/drivers/iommu/iommu-priv.h new file mode 100644 index 000000000000..e3e3b2015854 --- /dev/null +++ b/drivers/iommu/iommu-priv.h @@ -0,0 +1,19 @@ +/* SPDX-License-Identifier: GPL-2.0-only */ +/* Copyright (c) 2023, NVIDIA CORPORATION & AFFILIATES. + */ +#ifndef __LINUX_IOMMU_PRIV_H +#define __LINUX_IOMMU_PRIV_H + +#include <linux/iommu.h> + +int iommu_group_replace_domain(struct iommu_group *group, + struct iommu_domain *new_domain); + +int iommu_device_register_bus(struct iommu_device *iommu, + const struct iommu_ops *ops, struct bus_type *bus, + struct notifier_block *nb); +void iommu_device_unregister_bus(struct iommu_device *iommu, + struct bus_type *bus, + struct notifier_block *nb); + +#endif /* __LINUX_IOMMU_PRIV_H */ diff --git a/drivers/iommu/iommu.c b/drivers/iommu/iommu.c index caaf563d38ae..c9c370de9d3d 100644 --- a/drivers/iommu/iommu.c +++ b/drivers/iommu/iommu.c @@ -34,8 +34,10 @@ #include <linux/msi.h> #include "dma-iommu.h" +#include "iommu-priv.h" #include "iommu-sva.h" +#include "iommu-priv.h" static struct kset *iommu_group_kset; static DEFINE_IDA(iommu_group_ida); @@ -287,6 +289,48 @@ void iommu_device_unregister(struct iommu_device *iommu) } EXPORT_SYMBOL_GPL(iommu_device_unregister); +#if IS_ENABLED(CONFIG_IOMMUFD_TEST) +void iommu_device_unregister_bus(struct iommu_device *iommu, + struct bus_type *bus, + struct notifier_block *nb) +{ + bus_unregister_notifier(bus, nb); + iommu_device_unregister(iommu); +} +EXPORT_SYMBOL_GPL(iommu_device_unregister_bus); + +/* + * Register an iommu driver against a single bus. This is only used by iommufd + * selftest to create a mock iommu driver. The caller must provide + * some memory to hold a notifier_block. + */ +int iommu_device_register_bus(struct iommu_device *iommu, + const struct iommu_ops *ops, struct bus_type *bus, + struct notifier_block *nb) +{ + int err; + + iommu->ops = ops; + nb->notifier_call = iommu_bus_notifier; + err = bus_register_notifier(bus, nb); + if (err) + return err; + + spin_lock(&iommu_device_lock); + list_add_tail(&iommu->list, &iommu_device_list); + spin_unlock(&iommu_device_lock); + + bus->iommu_ops = ops; + err = bus_iommu_probe(bus); + if (err) { + iommu_device_unregister_bus(iommu, bus, nb); + return err; + } + return 0; +} +EXPORT_SYMBOL_GPL(iommu_device_register_bus); +#endif + static struct dev_iommu *dev_iommu_get(struct device *dev) { struct dev_iommu *param = dev->iommu; @@ -2114,6 +2158,32 @@ int iommu_attach_group(struct iommu_domain *domain, struct iommu_group *group) } EXPORT_SYMBOL_GPL(iommu_attach_group); +/** + * iommu_group_replace_domain - replace the domain that a group is attached to + * @new_domain: new IOMMU domain to replace with + * @group: IOMMU group that will be attached to the new domain + * + * This API allows the group to switch domains without being forced to go to + * the blocking domain in-between. + * + * If the currently attached domain is a core domain (e.g. a default_domain), + * it will act just like the iommu_attach_group(). + */ +int iommu_group_replace_domain(struct iommu_group *group, + struct iommu_domain *new_domain) +{ + int ret; + + if (!new_domain) + return -EINVAL; + + mutex_lock(&group->mutex); + ret = __iommu_group_set_domain(group, new_domain); + mutex_unlock(&group->mutex); + return ret; +} +EXPORT_SYMBOL_NS_GPL(iommu_group_replace_domain, IOMMUFD_INTERNAL); + static int __iommu_device_set_domain(struct iommu_group *group, struct device *dev, struct iommu_domain *new_domain, @@ -2642,6 +2712,14 @@ int iommu_set_pgtable_quirks(struct iommu_domain *domain, } EXPORT_SYMBOL_GPL(iommu_set_pgtable_quirks); +/** + * iommu_get_resv_regions - get reserved regions + * @dev: device for which to get reserved regions + * @list: reserved region list for device + * + * This returns a list of reserved IOVA regions specific to this device. + * A domain user should not map IOVA in these ranges. + */ void iommu_get_resv_regions(struct device *dev, struct list_head *list) { const struct iommu_ops *ops = dev_iommu_ops(dev); @@ -2649,9 +2727,10 @@ void iommu_get_resv_regions(struct device *dev, struct list_head *list) if (ops->get_resv_regions) ops->get_resv_regions(dev, list); } +EXPORT_SYMBOL_GPL(iommu_get_resv_regions); /** - * iommu_put_resv_regions - release resered regions + * iommu_put_resv_regions - release reserved regions * @dev: device for which to free reserved regions * @list: reserved region list for device * diff --git a/drivers/iommu/iommufd/Kconfig b/drivers/iommu/iommufd/Kconfig index ada693ea51a7..99d4b075df49 100644 --- a/drivers/iommu/iommufd/Kconfig +++ b/drivers/iommu/iommufd/Kconfig @@ -14,8 +14,8 @@ config IOMMUFD if IOMMUFD config IOMMUFD_VFIO_CONTAINER bool "IOMMUFD provides the VFIO container /dev/vfio/vfio" - depends on VFIO && !VFIO_CONTAINER - default VFIO && !VFIO_CONTAINER + depends on VFIO_GROUP && !VFIO_CONTAINER + default VFIO_GROUP && !VFIO_CONTAINER help IOMMUFD will provide /dev/vfio/vfio instead of VFIO. This relies on IOMMUFD providing compatibility emulation to give the same ioctls. diff --git a/drivers/iommu/iommufd/device.c b/drivers/iommu/iommufd/device.c index ed2937a4e196..90f88c295ce0 100644 --- a/drivers/iommu/iommufd/device.c +++ b/drivers/iommu/iommufd/device.c @@ -4,6 +4,7 @@ #include <linux/iommufd.h> #include <linux/slab.h> #include <linux/iommu.h> +#include "../iommu-priv.h" #include "io_pagetable.h" #include "iommufd_private.h" @@ -15,13 +16,127 @@ MODULE_PARM_DESC( "Allow IOMMUFD to bind to devices even if the platform cannot isolate " "the MSI interrupt window. Enabling this is a security weakness."); +static void iommufd_group_release(struct kref *kref) +{ + struct iommufd_group *igroup = + container_of(kref, struct iommufd_group, ref); + + WARN_ON(igroup->hwpt || !list_empty(&igroup->device_list)); + + xa_cmpxchg(&igroup->ictx->groups, iommu_group_id(igroup->group), igroup, + NULL, GFP_KERNEL); + iommu_group_put(igroup->group); + mutex_destroy(&igroup->lock); + kfree(igroup); +} + +static void iommufd_put_group(struct iommufd_group *group) +{ + kref_put(&group->ref, iommufd_group_release); +} + +static bool iommufd_group_try_get(struct iommufd_group *igroup, + struct iommu_group *group) +{ + if (!igroup) + return false; + /* + * group ID's cannot be re-used until the group is put back which does + * not happen if we could get an igroup pointer under the xa_lock. + */ + if (WARN_ON(igroup->group != group)) + return false; + return kref_get_unless_zero(&igroup->ref); +} + +/* + * iommufd needs to store some more data for each iommu_group, we keep a + * parallel xarray indexed by iommu_group id to hold this instead of putting it + * in the core structure. To keep things simple the iommufd_group memory is + * unique within the iommufd_ctx. This makes it easy to check there are no + * memory leaks. + */ +static struct iommufd_group *iommufd_get_group(struct iommufd_ctx *ictx, + struct device *dev) +{ + struct iommufd_group *new_igroup; + struct iommufd_group *cur_igroup; + struct iommufd_group *igroup; + struct iommu_group *group; + unsigned int id; + + group = iommu_group_get(dev); + if (!group) + return ERR_PTR(-ENODEV); + + id = iommu_group_id(group); + + xa_lock(&ictx->groups); + igroup = xa_load(&ictx->groups, id); + if (iommufd_group_try_get(igroup, group)) { + xa_unlock(&ictx->groups); + iommu_group_put(group); + return igroup; + } + xa_unlock(&ictx->groups); + + new_igroup = kzalloc(sizeof(*new_igroup), GFP_KERNEL); + if (!new_igroup) { + iommu_group_put(group); + return ERR_PTR(-ENOMEM); + } + + kref_init(&new_igroup->ref); + mutex_init(&new_igroup->lock); + INIT_LIST_HEAD(&new_igroup->device_list); + new_igroup->sw_msi_start = PHYS_ADDR_MAX; + /* group reference moves into new_igroup */ + new_igroup->group = group; + + /* + * The ictx is not additionally refcounted here becase all objects using + * an igroup must put it before their destroy completes. + */ + new_igroup->ictx = ictx; + + /* + * We dropped the lock so igroup is invalid. NULL is a safe and likely + * value to assume for the xa_cmpxchg algorithm. + */ + cur_igroup = NULL; + xa_lock(&ictx->groups); + while (true) { + igroup = __xa_cmpxchg(&ictx->groups, id, cur_igroup, new_igroup, + GFP_KERNEL); + if (xa_is_err(igroup)) { + xa_unlock(&ictx->groups); + iommufd_put_group(new_igroup); + return ERR_PTR(xa_err(igroup)); + } + + /* new_group was successfully installed */ + if (cur_igroup == igroup) { + xa_unlock(&ictx->groups); + return new_igroup; + } + + /* Check again if the current group is any good */ + if (iommufd_group_try_get(igroup, group)) { + xa_unlock(&ictx->groups); + iommufd_put_group(new_igroup); + return igroup; + } + cur_igroup = igroup; + } +} + void iommufd_device_destroy(struct iommufd_object *obj) { struct iommufd_device *idev = container_of(obj, struct iommufd_device, obj); iommu_device_release_dma_owner(idev->dev); - iommu_group_put(idev->group); + iommufd_put_group(idev->igroup); if (!iommufd_selftest_is_mock_dev(idev->dev)) iommufd_ctx_put(idev->ictx); } @@ -46,7 +161,7 @@ struct iommufd_device *iommufd_device_bind(struct iommufd_ctx *ictx, struct device *dev, u32 *id) { struct iommufd_device *idev; - struct iommu_group *group; + struct iommufd_group *igroup; int rc; /* @@ -56,9 +171,29 @@ struct iommufd_device *iommufd_device_bind(struct iommufd_ctx *ictx, if (!device_iommu_capable(dev, IOMMU_CAP_CACHE_COHERENCY)) return ERR_PTR(-EINVAL); - group = iommu_group_get(dev); - if (!group) - return ERR_PTR(-ENODEV); + igroup = iommufd_get_group(ictx, dev); + if (IS_ERR(igroup)) + return ERR_CAST(igroup); + + /* + * For historical compat with VFIO the insecure interrupt path is + * allowed if the module parameter is set. Secure/Isolated means that a + * MemWr operation from the device (eg a simple DMA) cannot trigger an + * interrupt outside this iommufd context. + */ + if (!iommufd_selftest_is_mock_dev(dev) && + !iommu_group_has_isolated_msi(igroup->group)) { + if (!allow_unsafe_interrupts) { + rc = -EPERM; + goto out_group_put; + } + + dev_warn( + dev, + "MSI interrupts are not secure, they cannot be isolated by the platform. " + "Check that platform features like interrupt remapping are enabled. " + "Use the \"allow_unsafe_interrupts\" module parameter to override\n"); + } rc = iommu_device_claim_dma_owner(dev, ictx); if (rc) @@ -77,8 +212,8 @@ struct iommufd_device *iommufd_device_bind(struct iommufd_ctx *ictx, device_iommu_capable(dev, IOMMU_CAP_ENFORCE_CACHE_COHERENCY); /* The calling driver is a user until iommufd_device_unbind() */ refcount_inc(&idev->obj.users); - /* group refcount moves into iommufd_device */ - idev->group = group; + /* igroup refcount moves into iommufd_device */ + idev->igroup = igroup; /* * If the caller fails after this success it must call @@ -93,12 +228,43 @@ struct iommufd_device *iommufd_device_bind(struct iommufd_ctx *ictx, out_release_owner: iommu_device_release_dma_owner(dev); out_group_put: - iommu_group_put(group); + iommufd_put_group(igroup); return ERR_PTR(rc); } EXPORT_SYMBOL_NS_GPL(iommufd_device_bind, IOMMUFD); /** + * iommufd_ctx_has_group - True if any device within the group is bound + * to the ictx + * @ictx: iommufd file descriptor + * @group: Pointer to a physical iommu_group struct + * + * True if any device within the group has been bound to this ictx, ex. via + * iommufd_device_bind(), therefore implying ictx ownership of the group. + */ +bool iommufd_ctx_has_group(struct iommufd_ctx *ictx, struct iommu_group *group) +{ + struct iommufd_object *obj; + unsigned long index; + + if (!ictx || !group) + return false; + + xa_lock(&ictx->objects); + xa_for_each(&ictx->objects, index, obj) { + if (obj->type == IOMMUFD_OBJ_DEVICE && + container_of(obj, struct iommufd_device, obj) + ->igroup->group == group) { + xa_unlock(&ictx->objects); + return true; + } + } + xa_unlock(&ictx->objects); + return false; +} +EXPORT_SYMBOL_NS_GPL(iommufd_ctx_has_group, IOMMUFD); + +/** * iommufd_device_unbind - Undo iommufd_device_bind() * @idev: Device returned by iommufd_device_bind() * @@ -113,10 +279,22 @@ void iommufd_device_unbind(struct iommufd_device *idev) } EXPORT_SYMBOL_NS_GPL(iommufd_device_unbind, IOMMUFD); -static int iommufd_device_setup_msi(struct iommufd_device *idev, - struct iommufd_hw_pagetable *hwpt, - phys_addr_t sw_msi_start) +struct iommufd_ctx *iommufd_device_to_ictx(struct iommufd_device *idev) +{ + return idev->ictx; +} +EXPORT_SYMBOL_NS_GPL(iommufd_device_to_ictx, IOMMUFD); + +u32 iommufd_device_to_id(struct iommufd_device *idev) +{ + return idev->obj.id; +} +EXPORT_SYMBOL_NS_GPL(iommufd_device_to_id, IOMMUFD); + +static int iommufd_group_setup_msi(struct iommufd_group *igroup, + struct iommufd_hw_pagetable *hwpt) { + phys_addr_t sw_msi_start = igroup->sw_msi_start; int rc; /* @@ -143,128 +321,192 @@ static int iommufd_device_setup_msi(struct iommufd_device *idev, */ hwpt->msi_cookie = true; } - - /* - * For historical compat with VFIO the insecure interrupt path is - * allowed if the module parameter is set. Insecure means that a MemWr - * operation from the device (eg a simple DMA) cannot trigger an - * interrupt outside this iommufd context. - */ - if (!iommufd_selftest_is_mock_dev(idev->dev) && - !iommu_group_has_isolated_msi(idev->group)) { - if (!allow_unsafe_interrupts) - return -EPERM; - - dev_warn( - idev->dev, - "MSI interrupts are not secure, they cannot be isolated by the platform. " - "Check that platform features like interrupt remapping are enabled. " - "Use the \"allow_unsafe_interrupts\" module parameter to override\n"); - } return 0; } -static bool iommufd_hw_pagetable_has_group(struct iommufd_hw_pagetable *hwpt, - struct iommu_group *group) -{ - struct iommufd_device *cur_dev; - - lockdep_assert_held(&hwpt->devices_lock); - - list_for_each_entry(cur_dev, &hwpt->devices, devices_item) - if (cur_dev->group == group) - return true; - return false; -} - int iommufd_hw_pagetable_attach(struct iommufd_hw_pagetable *hwpt, struct iommufd_device *idev) { - phys_addr_t sw_msi_start = PHYS_ADDR_MAX; int rc; - lockdep_assert_held(&hwpt->devices_lock); + mutex_lock(&idev->igroup->lock); - if (WARN_ON(idev->hwpt)) - return -EINVAL; - - /* - * Try to upgrade the domain we have, it is an iommu driver bug to - * report IOMMU_CAP_ENFORCE_CACHE_COHERENCY but fail - * enforce_cache_coherency when there are no devices attached to the - * domain. - */ - if (idev->enforce_cache_coherency && !hwpt->enforce_cache_coherency) { - if (hwpt->domain->ops->enforce_cache_coherency) - hwpt->enforce_cache_coherency = - hwpt->domain->ops->enforce_cache_coherency( - hwpt->domain); - if (!hwpt->enforce_cache_coherency) { - WARN_ON(list_empty(&hwpt->devices)); - return -EINVAL; - } + if (idev->igroup->hwpt != NULL && idev->igroup->hwpt != hwpt) { + rc = -EINVAL; + goto err_unlock; } - rc = iopt_table_enforce_group_resv_regions(&hwpt->ioas->iopt, idev->dev, - idev->group, &sw_msi_start); - if (rc) - return rc; + /* Try to upgrade the domain we have */ + if (idev->enforce_cache_coherency) { + rc = iommufd_hw_pagetable_enforce_cc(hwpt); + if (rc) + goto err_unlock; + } - rc = iommufd_device_setup_msi(idev, hwpt, sw_msi_start); + rc = iopt_table_enforce_dev_resv_regions(&hwpt->ioas->iopt, idev->dev, + &idev->igroup->sw_msi_start); if (rc) - goto err_unresv; + goto err_unlock; /* - * FIXME: Hack around missing a device-centric iommu api, only attach to - * the group once for the first device that is in the group. + * Only attach to the group once for the first device that is in the + * group. All the other devices will follow this attachment. The user + * should attach every device individually to the hwpt as the per-device + * reserved regions are only updated during individual device + * attachment. */ - if (!iommufd_hw_pagetable_has_group(hwpt, idev->group)) { - rc = iommu_attach_group(hwpt->domain, idev->group); + if (list_empty(&idev->igroup->device_list)) { + rc = iommufd_group_setup_msi(idev->igroup, hwpt); if (rc) goto err_unresv; + + rc = iommu_attach_group(hwpt->domain, idev->igroup->group); + if (rc) + goto err_unresv; + idev->igroup->hwpt = hwpt; } + refcount_inc(&hwpt->obj.users); + list_add_tail(&idev->group_item, &idev->igroup->device_list); + mutex_unlock(&idev->igroup->lock); return 0; err_unresv: iopt_remove_reserved_iova(&hwpt->ioas->iopt, idev->dev); +err_unlock: + mutex_unlock(&idev->igroup->lock); return rc; } -void iommufd_hw_pagetable_detach(struct iommufd_hw_pagetable *hwpt, - struct iommufd_device *idev) +struct iommufd_hw_pagetable * +iommufd_hw_pagetable_detach(struct iommufd_device *idev) { - if (!iommufd_hw_pagetable_has_group(hwpt, idev->group)) - iommu_detach_group(hwpt->domain, idev->group); + struct iommufd_hw_pagetable *hwpt = idev->igroup->hwpt; + + mutex_lock(&idev->igroup->lock); + list_del(&idev->group_item); + if (list_empty(&idev->igroup->device_list)) { + iommu_detach_group(hwpt->domain, idev->igroup->group); + idev->igroup->hwpt = NULL; + } iopt_remove_reserved_iova(&hwpt->ioas->iopt, idev->dev); + mutex_unlock(&idev->igroup->lock); + + /* Caller must destroy hwpt */ + return hwpt; } -static int iommufd_device_do_attach(struct iommufd_device *idev, - struct iommufd_hw_pagetable *hwpt) +static struct iommufd_hw_pagetable * +iommufd_device_do_attach(struct iommufd_device *idev, + struct iommufd_hw_pagetable *hwpt) { int rc; - mutex_lock(&hwpt->devices_lock); rc = iommufd_hw_pagetable_attach(hwpt, idev); if (rc) - goto out_unlock; + return ERR_PTR(rc); + return NULL; +} - idev->hwpt = hwpt; - refcount_inc(&hwpt->obj.users); - list_add(&idev->devices_item, &hwpt->devices); -out_unlock: - mutex_unlock(&hwpt->devices_lock); - return rc; +static struct iommufd_hw_pagetable * +iommufd_device_do_replace(struct iommufd_device *idev, + struct iommufd_hw_pagetable *hwpt) +{ + struct iommufd_group *igroup = idev->igroup; + struct iommufd_hw_pagetable *old_hwpt; + unsigned int num_devices = 0; + struct iommufd_device *cur; + int rc; + + mutex_lock(&idev->igroup->lock); + + if (igroup->hwpt == NULL) { + rc = -EINVAL; + goto err_unlock; + } + + if (hwpt == igroup->hwpt) { + mutex_unlock(&idev->igroup->lock); + return NULL; + } + + /* Try to upgrade the domain we have */ + list_for_each_entry(cur, &igroup->device_list, group_item) { + num_devices++; + if (cur->enforce_cache_coherency) { + rc = iommufd_hw_pagetable_enforce_cc(hwpt); + if (rc) + goto err_unlock; + } + } + + old_hwpt = igroup->hwpt; + if (hwpt->ioas != old_hwpt->ioas) { + list_for_each_entry(cur, &igroup->device_list, group_item) { + rc = iopt_table_enforce_dev_resv_regions( + &hwpt->ioas->iopt, cur->dev, NULL); + if (rc) + goto err_unresv; + } + } + + rc = iommufd_group_setup_msi(idev->igroup, hwpt); + if (rc) + goto err_unresv; + + rc = iommu_group_replace_domain(igroup->group, hwpt->domain); + if (rc) + goto err_unresv; + + if (hwpt->ioas != old_hwpt->ioas) { + list_for_each_entry(cur, &igroup->device_list, group_item) + iopt_remove_reserved_iova(&old_hwpt->ioas->iopt, + cur->dev); + } + + igroup->hwpt = hwpt; + + /* + * Move the refcounts held by the device_list to the new hwpt. Retain a + * refcount for this thread as the caller will free it. + */ + refcount_add(num_devices, &hwpt->obj.users); + if (num_devices > 1) + WARN_ON(refcount_sub_and_test(num_devices - 1, + &old_hwpt->obj.users)); + mutex_unlock(&idev->igroup->lock); + + /* Caller must destroy old_hwpt */ + return old_hwpt; +err_unresv: + list_for_each_entry(cur, &igroup->device_list, group_item) + iopt_remove_reserved_iova(&hwpt->ioas->iopt, cur->dev); +err_unlock: + mutex_unlock(&idev->igroup->lock); + return ERR_PTR(rc); } +typedef struct iommufd_hw_pagetable *(*attach_fn)( + struct iommufd_device *idev, struct iommufd_hw_pagetable *hwpt); + /* * When automatically managing the domains we search for a compatible domain in * the iopt and if one is found use it, otherwise create a new domain. * Automatic domain selection will never pick a manually created domain. */ -static int iommufd_device_auto_get_domain(struct iommufd_device *idev, - struct iommufd_ioas *ioas) +static struct iommufd_hw_pagetable * +iommufd_device_auto_get_domain(struct iommufd_device *idev, + struct iommufd_ioas *ioas, u32 *pt_id, + attach_fn do_attach) { + /* + * iommufd_hw_pagetable_attach() is called by + * iommufd_hw_pagetable_alloc() in immediate attachment mode, same as + * iommufd_device_do_attach(). So if we are in this mode then we prefer + * to use the immediate_attach path as it supports drivers that can't + * directly allocate a domain. + */ + bool immediate_attach = do_attach == iommufd_device_do_attach; + struct iommufd_hw_pagetable *destroy_hwpt; struct iommufd_hw_pagetable *hwpt; - int rc; /* * There is no differentiation when domains are allocated, so any domain @@ -278,50 +520,58 @@ static int iommufd_device_auto_get_domain(struct iommufd_device *idev, if (!iommufd_lock_obj(&hwpt->obj)) continue; - rc = iommufd_device_do_attach(idev, hwpt); + destroy_hwpt = (*do_attach)(idev, hwpt); + if (IS_ERR(destroy_hwpt)) { + iommufd_put_object(&hwpt->obj); + /* + * -EINVAL means the domain is incompatible with the + * device. Other error codes should propagate to + * userspace as failure. Success means the domain is + * attached. + */ + if (PTR_ERR(destroy_hwpt) == -EINVAL) + continue; + goto out_unlock; + } + *pt_id = hwpt->obj.id; iommufd_put_object(&hwpt->obj); - - /* - * -EINVAL means the domain is incompatible with the device. - * Other error codes should propagate to userspace as failure. - * Success means the domain is attached. - */ - if (rc == -EINVAL) - continue; goto out_unlock; } - hwpt = iommufd_hw_pagetable_alloc(idev->ictx, ioas, idev, true); + hwpt = iommufd_hw_pagetable_alloc(idev->ictx, ioas, idev, + immediate_attach); if (IS_ERR(hwpt)) { - rc = PTR_ERR(hwpt); + destroy_hwpt = ERR_CAST(hwpt); goto out_unlock; } + + if (!immediate_attach) { + destroy_hwpt = (*do_attach)(idev, hwpt); + if (IS_ERR(destroy_hwpt)) + goto out_abort; + } else { + destroy_hwpt = NULL; + } + hwpt->auto_domain = true; + *pt_id = hwpt->obj.id; - mutex_unlock(&ioas->mutex); iommufd_object_finalize(idev->ictx, &hwpt->obj); - return 0; + mutex_unlock(&ioas->mutex); + return destroy_hwpt; + +out_abort: + iommufd_object_abort_and_destroy(idev->ictx, &hwpt->obj); out_unlock: mutex_unlock(&ioas->mutex); - return rc; + return destroy_hwpt; } -/** - * iommufd_device_attach - Connect a device from an iommu_domain - * @idev: device to attach - * @pt_id: Input a IOMMUFD_OBJ_IOAS, or IOMMUFD_OBJ_HW_PAGETABLE - * Output the IOMMUFD_OBJ_HW_PAGETABLE ID - * - * This connects the device to an iommu_domain, either automatically or manually - * selected. Once this completes the device could do DMA. - * - * The caller should return the resulting pt_id back to userspace. - * This function is undone by calling iommufd_device_detach(). - */ -int iommufd_device_attach(struct iommufd_device *idev, u32 *pt_id) +static int iommufd_device_change_pt(struct iommufd_device *idev, u32 *pt_id, + attach_fn do_attach) { + struct iommufd_hw_pagetable *destroy_hwpt; struct iommufd_object *pt_obj; - int rc; pt_obj = iommufd_get_object(idev->ictx, *pt_id, IOMMUFD_OBJ_ANY); if (IS_ERR(pt_obj)) @@ -332,8 +582,8 @@ int iommufd_device_attach(struct iommufd_device *idev, u32 *pt_id) struct iommufd_hw_pagetable *hwpt = container_of(pt_obj, struct iommufd_hw_pagetable, obj); - rc = iommufd_device_do_attach(idev, hwpt); - if (rc) + destroy_hwpt = (*do_attach)(idev, hwpt); + if (IS_ERR(destroy_hwpt)) goto out_put_pt_obj; break; } @@ -341,27 +591,80 @@ int iommufd_device_attach(struct iommufd_device *idev, u32 *pt_id) struct iommufd_ioas *ioas = container_of(pt_obj, struct iommufd_ioas, obj); - rc = iommufd_device_auto_get_domain(idev, ioas); - if (rc) + destroy_hwpt = iommufd_device_auto_get_domain(idev, ioas, pt_id, + do_attach); + if (IS_ERR(destroy_hwpt)) goto out_put_pt_obj; break; } default: - rc = -EINVAL; + destroy_hwpt = ERR_PTR(-EINVAL); goto out_put_pt_obj; } + iommufd_put_object(pt_obj); - refcount_inc(&idev->obj.users); - *pt_id = idev->hwpt->obj.id; - rc = 0; + /* This destruction has to be after we unlock everything */ + if (destroy_hwpt) + iommufd_hw_pagetable_put(idev->ictx, destroy_hwpt); + return 0; out_put_pt_obj: iommufd_put_object(pt_obj); - return rc; + return PTR_ERR(destroy_hwpt); +} + +/** + * iommufd_device_attach - Connect a device to an iommu_domain + * @idev: device to attach + * @pt_id: Input a IOMMUFD_OBJ_IOAS, or IOMMUFD_OBJ_HW_PAGETABLE + * Output the IOMMUFD_OBJ_HW_PAGETABLE ID + * + * This connects the device to an iommu_domain, either automatically or manually + * selected. Once this completes the device could do DMA. + * + * The caller should return the resulting pt_id back to userspace. + * This function is undone by calling iommufd_device_detach(). + */ +int iommufd_device_attach(struct iommufd_device *idev, u32 *pt_id) +{ + int rc; + + rc = iommufd_device_change_pt(idev, pt_id, &iommufd_device_do_attach); + if (rc) + return rc; + + /* + * Pairs with iommufd_device_detach() - catches caller bugs attempting + * to destroy a device with an attachment. + */ + refcount_inc(&idev->obj.users); + return 0; } EXPORT_SYMBOL_NS_GPL(iommufd_device_attach, IOMMUFD); /** + * iommufd_device_replace - Change the device's iommu_domain + * @idev: device to change + * @pt_id: Input a IOMMUFD_OBJ_IOAS, or IOMMUFD_OBJ_HW_PAGETABLE + * Output the IOMMUFD_OBJ_HW_PAGETABLE ID + * + * This is the same as:: + * + * iommufd_device_detach(); + * iommufd_device_attach(); + * + * If it fails then no change is made to the attachment. The iommu driver may + * implement this so there is no disruption in translation. This can only be + * called if iommufd_device_attach() has already succeeded. + */ +int iommufd_device_replace(struct iommufd_device *idev, u32 *pt_id) +{ + return iommufd_device_change_pt(idev, pt_id, + &iommufd_device_do_replace); +} +EXPORT_SYMBOL_NS_GPL(iommufd_device_replace, IOMMUFD); + +/** * iommufd_device_detach - Disconnect a device to an iommu_domain * @idev: device to detach * @@ -370,33 +673,87 @@ EXPORT_SYMBOL_NS_GPL(iommufd_device_attach, IOMMUFD); */ void iommufd_device_detach(struct iommufd_device *idev) { - struct iommufd_hw_pagetable *hwpt = idev->hwpt; - - mutex_lock(&hwpt->devices_lock); - list_del(&idev->devices_item); - idev->hwpt = NULL; - iommufd_hw_pagetable_detach(hwpt, idev); - mutex_unlock(&hwpt->devices_lock); - - if (hwpt->auto_domain) - iommufd_object_deref_user(idev->ictx, &hwpt->obj); - else - refcount_dec(&hwpt->obj.users); + struct iommufd_hw_pagetable *hwpt; + hwpt = iommufd_hw_pagetable_detach(idev); + iommufd_hw_pagetable_put(idev->ictx, hwpt); refcount_dec(&idev->obj.users); } EXPORT_SYMBOL_NS_GPL(iommufd_device_detach, IOMMUFD); +/* + * On success, it will refcount_inc() at a valid new_ioas and refcount_dec() at + * a valid cur_ioas (access->ioas). A caller passing in a valid new_ioas should + * call iommufd_put_object() if it does an iommufd_get_object() for a new_ioas. + */ +static int iommufd_access_change_ioas(struct iommufd_access *access, + struct iommufd_ioas *new_ioas) +{ + u32 iopt_access_list_id = access->iopt_access_list_id; + struct iommufd_ioas *cur_ioas = access->ioas; + int rc; + + lockdep_assert_held(&access->ioas_lock); + + /* We are racing with a concurrent detach, bail */ + if (cur_ioas != access->ioas_unpin) + return -EBUSY; + + if (cur_ioas == new_ioas) + return 0; + + /* + * Set ioas to NULL to block any further iommufd_access_pin_pages(). + * iommufd_access_unpin_pages() can continue using access->ioas_unpin. + */ + access->ioas = NULL; + + if (new_ioas) { + rc = iopt_add_access(&new_ioas->iopt, access); + if (rc) { + access->ioas = cur_ioas; + return rc; + } + refcount_inc(&new_ioas->obj.users); + } + + if (cur_ioas) { + if (access->ops->unmap) { + mutex_unlock(&access->ioas_lock); + access->ops->unmap(access->data, 0, ULONG_MAX); + mutex_lock(&access->ioas_lock); + } + iopt_remove_access(&cur_ioas->iopt, access, iopt_access_list_id); + refcount_dec(&cur_ioas->obj.users); + } + + access->ioas = new_ioas; + access->ioas_unpin = new_ioas; + + return 0; +} + +static int iommufd_access_change_ioas_id(struct iommufd_access *access, u32 id) +{ + struct iommufd_ioas *ioas = iommufd_get_ioas(access->ictx, id); + int rc; + + if (IS_ERR(ioas)) + return PTR_ERR(ioas); + rc = iommufd_access_change_ioas(access, ioas); + iommufd_put_object(&ioas->obj); + return rc; +} + void iommufd_access_destroy_object(struct iommufd_object *obj) { struct iommufd_access *access = container_of(obj, struct iommufd_access, obj); - if (access->ioas) { - iopt_remove_access(&access->ioas->iopt, access); - refcount_dec(&access->ioas->obj.users); - access->ioas = NULL; - } + mutex_lock(&access->ioas_lock); + if (access->ioas) + WARN_ON(iommufd_access_change_ioas(access, NULL)); + mutex_unlock(&access->ioas_lock); iommufd_ctx_put(access->ictx); } @@ -441,6 +798,7 @@ iommufd_access_create(struct iommufd_ctx *ictx, iommufd_ctx_get(ictx); iommufd_object_finalize(ictx, &access->obj); *id = access->obj.id; + mutex_init(&access->ioas_lock); return access; } EXPORT_SYMBOL_NS_GPL(iommufd_access_create, IOMMUFD); @@ -457,30 +815,49 @@ void iommufd_access_destroy(struct iommufd_access *access) } EXPORT_SYMBOL_NS_GPL(iommufd_access_destroy, IOMMUFD); +void iommufd_access_detach(struct iommufd_access *access) +{ + mutex_lock(&access->ioas_lock); + if (WARN_ON(!access->ioas)) { + mutex_unlock(&access->ioas_lock); + return; + } + WARN_ON(iommufd_access_change_ioas(access, NULL)); + mutex_unlock(&access->ioas_lock); +} +EXPORT_SYMBOL_NS_GPL(iommufd_access_detach, IOMMUFD); + int iommufd_access_attach(struct iommufd_access *access, u32 ioas_id) { - struct iommufd_ioas *new_ioas; - int rc = 0; + int rc; - if (access->ioas) + mutex_lock(&access->ioas_lock); + if (WARN_ON(access->ioas)) { + mutex_unlock(&access->ioas_lock); return -EINVAL; - - new_ioas = iommufd_get_ioas(access->ictx, ioas_id); - if (IS_ERR(new_ioas)) - return PTR_ERR(new_ioas); - - rc = iopt_add_access(&new_ioas->iopt, access); - if (rc) { - iommufd_put_object(&new_ioas->obj); - return rc; } - iommufd_ref_to_users(&new_ioas->obj); - access->ioas = new_ioas; - return 0; + rc = iommufd_access_change_ioas_id(access, ioas_id); + mutex_unlock(&access->ioas_lock); + return rc; } EXPORT_SYMBOL_NS_GPL(iommufd_access_attach, IOMMUFD); +int iommufd_access_replace(struct iommufd_access *access, u32 ioas_id) +{ + int rc; + + mutex_lock(&access->ioas_lock); + if (!access->ioas) { + mutex_unlock(&access->ioas_lock); + return -ENOENT; + } + rc = iommufd_access_change_ioas_id(access, ioas_id); + mutex_unlock(&access->ioas_lock); + return rc; +} +EXPORT_SYMBOL_NS_GPL(iommufd_access_replace, IOMMUFD); + /** * iommufd_access_notify_unmap - Notify users of an iopt to stop using it * @iopt: iopt to work on @@ -531,8 +908,8 @@ void iommufd_access_notify_unmap(struct io_pagetable *iopt, unsigned long iova, void iommufd_access_unpin_pages(struct iommufd_access *access, unsigned long iova, unsigned long length) { - struct io_pagetable *iopt = &access->ioas->iopt; struct iopt_area_contig_iter iter; + struct io_pagetable *iopt; unsigned long last_iova; struct iopt_area *area; @@ -540,6 +917,17 @@ void iommufd_access_unpin_pages(struct iommufd_access *access, WARN_ON(check_add_overflow(iova, length - 1, &last_iova))) return; + mutex_lock(&access->ioas_lock); + /* + * The driver must be doing something wrong if it calls this before an + * iommufd_access_attach() or after an iommufd_access_detach(). + */ + if (WARN_ON(!access->ioas_unpin)) { + mutex_unlock(&access->ioas_lock); + return; + } + iopt = &access->ioas_unpin->iopt; + down_read(&iopt->iova_rwsem); iopt_for_each_contig_area(&iter, area, iopt, iova, last_iova) iopt_area_remove_access( @@ -549,6 +937,7 @@ void iommufd_access_unpin_pages(struct iommufd_access *access, min(last_iova, iopt_area_last_iova(area)))); WARN_ON(!iopt_area_contig_done(&iter)); up_read(&iopt->iova_rwsem); + mutex_unlock(&access->ioas_lock); } EXPORT_SYMBOL_NS_GPL(iommufd_access_unpin_pages, IOMMUFD); @@ -594,8 +983,8 @@ int iommufd_access_pin_pages(struct iommufd_access *access, unsigned long iova, unsigned long length, struct page **out_pages, unsigned int flags) { - struct io_pagetable *iopt = &access->ioas->iopt; struct iopt_area_contig_iter iter; + struct io_pagetable *iopt; unsigned long last_iova; struct iopt_area *area; int rc; @@ -610,6 +999,13 @@ int iommufd_access_pin_pages(struct iommufd_access *access, unsigned long iova, if (check_add_overflow(iova, length - 1, &last_iova)) return -EOVERFLOW; + mutex_lock(&access->ioas_lock); + if (!access->ioas) { + mutex_unlock(&access->ioas_lock); + return -ENOENT; + } + iopt = &access->ioas->iopt; + down_read(&iopt->iova_rwsem); iopt_for_each_contig_area(&iter, area, iopt, iova, last_iova) { unsigned long last = min(last_iova, iopt_area_last_iova(area)); @@ -640,6 +1036,7 @@ int iommufd_access_pin_pages(struct iommufd_access *access, unsigned long iova, } up_read(&iopt->iova_rwsem); + mutex_unlock(&access->ioas_lock); return 0; err_remove: @@ -654,6 +1051,7 @@ err_remove: iopt_area_last_iova(area)))); } up_read(&iopt->iova_rwsem); + mutex_unlock(&access->ioas_lock); return rc; } EXPORT_SYMBOL_NS_GPL(iommufd_access_pin_pages, IOMMUFD); @@ -673,8 +1071,8 @@ EXPORT_SYMBOL_NS_GPL(iommufd_access_pin_pages, IOMMUFD); int iommufd_access_rw(struct iommufd_access *access, unsigned long iova, void *data, size_t length, unsigned int flags) { - struct io_pagetable *iopt = &access->ioas->iopt; struct iopt_area_contig_iter iter; + struct io_pagetable *iopt; struct iopt_area *area; unsigned long last_iova; int rc; @@ -684,6 +1082,13 @@ int iommufd_access_rw(struct iommufd_access *access, unsigned long iova, if (check_add_overflow(iova, length - 1, &last_iova)) return -EOVERFLOW; + mutex_lock(&access->ioas_lock); + if (!access->ioas) { + mutex_unlock(&access->ioas_lock); + return -ENOENT; + } + iopt = &access->ioas->iopt; + down_read(&iopt->iova_rwsem); iopt_for_each_contig_area(&iter, area, iopt, iova, last_iova) { unsigned long last = min(last_iova, iopt_area_last_iova(area)); @@ -710,6 +1115,7 @@ int iommufd_access_rw(struct iommufd_access *access, unsigned long iova, rc = -ENOENT; err_out: up_read(&iopt->iova_rwsem); + mutex_unlock(&access->ioas_lock); return rc; } EXPORT_SYMBOL_NS_GPL(iommufd_access_rw, IOMMUFD); diff --git a/drivers/iommu/iommufd/hw_pagetable.c b/drivers/iommu/iommufd/hw_pagetable.c index 6cdb6749d359..cf2c1504e20d 100644 --- a/drivers/iommu/iommufd/hw_pagetable.c +++ b/drivers/iommu/iommufd/hw_pagetable.c @@ -3,6 +3,7 @@ * Copyright (c) 2021-2022, NVIDIA CORPORATION & AFFILIATES */ #include <linux/iommu.h> +#include <uapi/linux/iommufd.h> #include "iommufd_private.h" @@ -11,8 +12,6 @@ void iommufd_hw_pagetable_destroy(struct iommufd_object *obj) struct iommufd_hw_pagetable *hwpt = container_of(obj, struct iommufd_hw_pagetable, obj); - WARN_ON(!list_empty(&hwpt->devices)); - if (!list_empty(&hwpt->hwpt_item)) { mutex_lock(&hwpt->ioas->mutex); list_del(&hwpt->hwpt_item); @@ -25,7 +24,35 @@ void iommufd_hw_pagetable_destroy(struct iommufd_object *obj) iommu_domain_free(hwpt->domain); refcount_dec(&hwpt->ioas->obj.users); - mutex_destroy(&hwpt->devices_lock); +} + +void iommufd_hw_pagetable_abort(struct iommufd_object *obj) +{ + struct iommufd_hw_pagetable *hwpt = + container_of(obj, struct iommufd_hw_pagetable, obj); + + /* The ioas->mutex must be held until finalize is called. */ + lockdep_assert_held(&hwpt->ioas->mutex); + + if (!list_empty(&hwpt->hwpt_item)) { + list_del_init(&hwpt->hwpt_item); + iopt_table_remove_domain(&hwpt->ioas->iopt, hwpt->domain); + } + iommufd_hw_pagetable_destroy(obj); +} + +int iommufd_hw_pagetable_enforce_cc(struct iommufd_hw_pagetable *hwpt) +{ + if (hwpt->enforce_cache_coherency) + return 0; + + if (hwpt->domain->ops->enforce_cache_coherency) + hwpt->enforce_cache_coherency = + hwpt->domain->ops->enforce_cache_coherency( + hwpt->domain); + if (!hwpt->enforce_cache_coherency) + return -EINVAL; + return 0; } /** @@ -38,6 +65,10 @@ void iommufd_hw_pagetable_destroy(struct iommufd_object *obj) * Allocate a new iommu_domain and return it as a hw_pagetable. The HWPT * will be linked to the given ioas and upon return the underlying iommu_domain * is fully popoulated. + * + * The caller must hold the ioas->mutex until after + * iommufd_object_abort_and_destroy() or iommufd_object_finalize() is called on + * the returned hwpt. */ struct iommufd_hw_pagetable * iommufd_hw_pagetable_alloc(struct iommufd_ctx *ictx, struct iommufd_ioas *ioas, @@ -52,9 +83,7 @@ iommufd_hw_pagetable_alloc(struct iommufd_ctx *ictx, struct iommufd_ioas *ioas, if (IS_ERR(hwpt)) return hwpt; - INIT_LIST_HEAD(&hwpt->devices); INIT_LIST_HEAD(&hwpt->hwpt_item); - mutex_init(&hwpt->devices_lock); /* Pairs with iommufd_hw_pagetable_destroy() */ refcount_inc(&ioas->obj.users); hwpt->ioas = ioas; @@ -65,7 +94,18 @@ iommufd_hw_pagetable_alloc(struct iommufd_ctx *ictx, struct iommufd_ioas *ioas, goto out_abort; } - mutex_lock(&hwpt->devices_lock); + /* + * Set the coherency mode before we do iopt_table_add_domain() as some + * iommus have a per-PTE bit that controls it and need to decide before + * doing any maps. It is an iommu driver bug to report + * IOMMU_CAP_ENFORCE_CACHE_COHERENCY but fail enforce_cache_coherency on + * a new domain. + */ + if (idev->enforce_cache_coherency) { + rc = iommufd_hw_pagetable_enforce_cc(hwpt); + if (WARN_ON(rc)) + goto out_abort; + } /* * immediate_attach exists only to accommodate iommu drivers that cannot @@ -76,30 +116,64 @@ iommufd_hw_pagetable_alloc(struct iommufd_ctx *ictx, struct iommufd_ioas *ioas, if (immediate_attach) { rc = iommufd_hw_pagetable_attach(hwpt, idev); if (rc) - goto out_unlock; + goto out_abort; } rc = iopt_table_add_domain(&hwpt->ioas->iopt, hwpt->domain); if (rc) goto out_detach; list_add_tail(&hwpt->hwpt_item, &hwpt->ioas->hwpt_list); - - if (immediate_attach) { - /* See iommufd_device_do_attach() */ - refcount_inc(&hwpt->obj.users); - idev->hwpt = hwpt; - list_add(&idev->devices_item, &hwpt->devices); - } - - mutex_unlock(&hwpt->devices_lock); return hwpt; out_detach: if (immediate_attach) - iommufd_hw_pagetable_detach(hwpt, idev); -out_unlock: - mutex_unlock(&hwpt->devices_lock); + iommufd_hw_pagetable_detach(idev); out_abort: iommufd_object_abort_and_destroy(ictx, &hwpt->obj); return ERR_PTR(rc); } + +int iommufd_hwpt_alloc(struct iommufd_ucmd *ucmd) +{ + struct iommu_hwpt_alloc *cmd = ucmd->cmd; + struct iommufd_hw_pagetable *hwpt; + struct iommufd_device *idev; + struct iommufd_ioas *ioas; + int rc; + + if (cmd->flags || cmd->__reserved) + return -EOPNOTSUPP; + + idev = iommufd_get_device(ucmd, cmd->dev_id); + if (IS_ERR(idev)) + return PTR_ERR(idev); + + ioas = iommufd_get_ioas(ucmd->ictx, cmd->pt_id); + if (IS_ERR(ioas)) { + rc = PTR_ERR(ioas); + goto out_put_idev; + } + + mutex_lock(&ioas->mutex); + hwpt = iommufd_hw_pagetable_alloc(ucmd->ictx, ioas, idev, false); + if (IS_ERR(hwpt)) { + rc = PTR_ERR(hwpt); + goto out_unlock; + } + + cmd->out_hwpt_id = hwpt->obj.id; + rc = iommufd_ucmd_respond(ucmd, sizeof(*cmd)); + if (rc) + goto out_hwpt; + iommufd_object_finalize(ucmd->ictx, &hwpt->obj); + goto out_unlock; + +out_hwpt: + iommufd_object_abort_and_destroy(ucmd->ictx, &hwpt->obj); +out_unlock: + mutex_unlock(&ioas->mutex); + iommufd_put_object(&ioas->obj); +out_put_idev: + iommufd_put_object(&idev->obj); + return rc; +} diff --git a/drivers/iommu/iommufd/io_pagetable.c b/drivers/iommu/iommufd/io_pagetable.c index 724c4c574241..3a598182b761 100644 --- a/drivers/iommu/iommufd/io_pagetable.c +++ b/drivers/iommu/iommufd/io_pagetable.c @@ -1158,36 +1158,36 @@ out_unlock: } void iopt_remove_access(struct io_pagetable *iopt, - struct iommufd_access *access) + struct iommufd_access *access, + u32 iopt_access_list_id) { down_write(&iopt->domains_rwsem); down_write(&iopt->iova_rwsem); - WARN_ON(xa_erase(&iopt->access_list, access->iopt_access_list_id) != - access); + WARN_ON(xa_erase(&iopt->access_list, iopt_access_list_id) != access); WARN_ON(iopt_calculate_iova_alignment(iopt)); up_write(&iopt->iova_rwsem); up_write(&iopt->domains_rwsem); } -/* Narrow the valid_iova_itree to include reserved ranges from a group. */ -int iopt_table_enforce_group_resv_regions(struct io_pagetable *iopt, - struct device *device, - struct iommu_group *group, - phys_addr_t *sw_msi_start) +/* Narrow the valid_iova_itree to include reserved ranges from a device. */ +int iopt_table_enforce_dev_resv_regions(struct io_pagetable *iopt, + struct device *dev, + phys_addr_t *sw_msi_start) { struct iommu_resv_region *resv; - struct iommu_resv_region *tmp; - LIST_HEAD(group_resv_regions); + LIST_HEAD(resv_regions); unsigned int num_hw_msi = 0; unsigned int num_sw_msi = 0; int rc; + if (iommufd_should_fail()) + return -EINVAL; + down_write(&iopt->iova_rwsem); - rc = iommu_get_group_resv_regions(group, &group_resv_regions); - if (rc) - goto out_unlock; + /* FIXME: drivers allocate memory but there is no failure propogated */ + iommu_get_resv_regions(dev, &resv_regions); - list_for_each_entry(resv, &group_resv_regions, list) { + list_for_each_entry(resv, &resv_regions, list) { if (resv->type == IOMMU_RESV_DIRECT_RELAXABLE) continue; @@ -1199,7 +1199,7 @@ int iopt_table_enforce_group_resv_regions(struct io_pagetable *iopt, } rc = iopt_reserve_iova(iopt, resv->start, - resv->length - 1 + resv->start, device); + resv->length - 1 + resv->start, dev); if (rc) goto out_reserved; } @@ -1214,11 +1214,9 @@ int iopt_table_enforce_group_resv_regions(struct io_pagetable *iopt, goto out_free_resv; out_reserved: - __iopt_remove_reserved_iova(iopt, device); + __iopt_remove_reserved_iova(iopt, dev); out_free_resv: - list_for_each_entry_safe(resv, tmp, &group_resv_regions, list) - kfree(resv); -out_unlock: + iommu_put_resv_regions(dev, &resv_regions); up_write(&iopt->iova_rwsem); return rc; } diff --git a/drivers/iommu/iommufd/iommufd_private.h b/drivers/iommu/iommufd/iommufd_private.h index f9790983699c..15596a08a057 100644 --- a/drivers/iommu/iommufd/iommufd_private.h +++ b/drivers/iommu/iommufd/iommufd_private.h @@ -17,6 +17,7 @@ struct iommufd_device; struct iommufd_ctx { struct file *file; struct xarray objects; + struct xarray groups; u8 account_mode; /* Compatibility with VFIO no iommu */ @@ -75,10 +76,9 @@ int iopt_table_add_domain(struct io_pagetable *iopt, struct iommu_domain *domain); void iopt_table_remove_domain(struct io_pagetable *iopt, struct iommu_domain *domain); -int iopt_table_enforce_group_resv_regions(struct io_pagetable *iopt, - struct device *device, - struct iommu_group *group, - phys_addr_t *sw_msi_start); +int iopt_table_enforce_dev_resv_regions(struct io_pagetable *iopt, + struct device *dev, + phys_addr_t *sw_msi_start); int iopt_set_allow_iova(struct io_pagetable *iopt, struct rb_root_cached *allowed_iova); int iopt_reserve_iova(struct io_pagetable *iopt, unsigned long start, @@ -119,6 +119,7 @@ enum iommufd_object_type { #ifdef CONFIG_IOMMUFD_TEST IOMMUFD_OBJ_SELFTEST, #endif + IOMMUFD_OBJ_MAX, }; /* Base struct for all objects with a userspace ID handle. */ @@ -260,18 +261,39 @@ struct iommufd_hw_pagetable { bool msi_cookie : 1; /* Head at iommufd_ioas::hwpt_list */ struct list_head hwpt_item; - struct mutex devices_lock; - struct list_head devices; }; struct iommufd_hw_pagetable * iommufd_hw_pagetable_alloc(struct iommufd_ctx *ictx, struct iommufd_ioas *ioas, struct iommufd_device *idev, bool immediate_attach); +int iommufd_hw_pagetable_enforce_cc(struct iommufd_hw_pagetable *hwpt); int iommufd_hw_pagetable_attach(struct iommufd_hw_pagetable *hwpt, struct iommufd_device *idev); -void iommufd_hw_pagetable_detach(struct iommufd_hw_pagetable *hwpt, - struct iommufd_device *idev); +struct iommufd_hw_pagetable * +iommufd_hw_pagetable_detach(struct iommufd_device *idev); void iommufd_hw_pagetable_destroy(struct iommufd_object *obj); +void iommufd_hw_pagetable_abort(struct iommufd_object *obj); +int iommufd_hwpt_alloc(struct iommufd_ucmd *ucmd); + +static inline void iommufd_hw_pagetable_put(struct iommufd_ctx *ictx, + struct iommufd_hw_pagetable *hwpt) +{ + lockdep_assert_not_held(&hwpt->ioas->mutex); + if (hwpt->auto_domain) + iommufd_object_deref_user(ictx, &hwpt->obj); + else + refcount_dec(&hwpt->obj.users); +} + +struct iommufd_group { + struct kref ref; + struct mutex lock; + struct iommufd_ctx *ictx; + struct iommu_group *group; + struct iommufd_hw_pagetable *hwpt; + struct list_head device_list; + phys_addr_t sw_msi_start; +}; /* * A iommufd_device object represents the binding relationship between a @@ -281,21 +303,29 @@ void iommufd_hw_pagetable_destroy(struct iommufd_object *obj); struct iommufd_device { struct iommufd_object obj; struct iommufd_ctx *ictx; - struct iommufd_hw_pagetable *hwpt; - /* Head at iommufd_hw_pagetable::devices */ - struct list_head devices_item; + struct iommufd_group *igroup; + struct list_head group_item; /* always the physical device */ struct device *dev; - struct iommu_group *group; bool enforce_cache_coherency; }; +static inline struct iommufd_device * +iommufd_get_device(struct iommufd_ucmd *ucmd, u32 id) +{ + return container_of(iommufd_get_object(ucmd->ictx, id, + IOMMUFD_OBJ_DEVICE), + struct iommufd_device, obj); +} + void iommufd_device_destroy(struct iommufd_object *obj); struct iommufd_access { struct iommufd_object obj; struct iommufd_ctx *ictx; struct iommufd_ioas *ioas; + struct iommufd_ioas *ioas_unpin; + struct mutex ioas_lock; const struct iommufd_access_ops *ops; void *data; unsigned long iova_alignment; @@ -304,7 +334,8 @@ struct iommufd_access { int iopt_add_access(struct io_pagetable *iopt, struct iommufd_access *access); void iopt_remove_access(struct io_pagetable *iopt, - struct iommufd_access *access); + struct iommufd_access *access, + u32 iopt_access_list_id); void iommufd_access_destroy_object(struct iommufd_object *obj); #ifdef CONFIG_IOMMUFD_TEST @@ -314,7 +345,7 @@ extern size_t iommufd_test_memory_limit; void iommufd_test_syz_conv_iova_id(struct iommufd_ucmd *ucmd, unsigned int ioas_id, u64 *iova, u32 *flags); bool iommufd_should_fail(void); -void __init iommufd_test_init(void); +int __init iommufd_test_init(void); void iommufd_test_exit(void); bool iommufd_selftest_is_mock_dev(struct device *dev); #else @@ -327,8 +358,9 @@ static inline bool iommufd_should_fail(void) { return false; } -static inline void __init iommufd_test_init(void) +static inline int __init iommufd_test_init(void) { + return 0; } static inline void iommufd_test_exit(void) { diff --git a/drivers/iommu/iommufd/iommufd_test.h b/drivers/iommu/iommufd/iommufd_test.h index b3d69cca7729..258de2253b61 100644 --- a/drivers/iommu/iommufd/iommufd_test.h +++ b/drivers/iommu/iommufd/iommufd_test.h @@ -17,6 +17,8 @@ enum { IOMMU_TEST_OP_ACCESS_PAGES, IOMMU_TEST_OP_ACCESS_RW, IOMMU_TEST_OP_SET_TEMP_MEMORY_LIMIT, + IOMMU_TEST_OP_MOCK_DOMAIN_REPLACE, + IOMMU_TEST_OP_ACCESS_REPLACE_IOAS, }; enum { @@ -51,8 +53,13 @@ struct iommu_test_cmd { struct { __u32 out_stdev_id; __u32 out_hwpt_id; + /* out_idev_id is the standard iommufd_bind object */ + __u32 out_idev_id; } mock_domain; struct { + __u32 pt_id; + } mock_domain_replace; + struct { __aligned_u64 iova; __aligned_u64 length; __aligned_u64 uptr; @@ -85,6 +92,9 @@ struct iommu_test_cmd { struct { __u32 limit; } memory_limit; + struct { + __u32 ioas_id; + } access_replace_ioas; }; __u32 last; }; diff --git a/drivers/iommu/iommufd/main.c b/drivers/iommu/iommufd/main.c index 4cf5f73f2708..5f7e9fa45502 100644 --- a/drivers/iommu/iommufd/main.c +++ b/drivers/iommu/iommufd/main.c @@ -24,6 +24,7 @@ struct iommufd_object_ops { void (*destroy)(struct iommufd_object *obj); + void (*abort)(struct iommufd_object *obj); }; static const struct iommufd_object_ops iommufd_object_ops[]; static struct miscdevice vfio_misc_dev; @@ -32,6 +33,7 @@ struct iommufd_object *_iommufd_object_alloc(struct iommufd_ctx *ictx, size_t size, enum iommufd_object_type type) { + static struct lock_class_key obj_keys[IOMMUFD_OBJ_MAX]; struct iommufd_object *obj; int rc; @@ -39,7 +41,15 @@ struct iommufd_object *_iommufd_object_alloc(struct iommufd_ctx *ictx, if (!obj) return ERR_PTR(-ENOMEM); obj->type = type; - init_rwsem(&obj->destroy_rwsem); + /* + * In most cases the destroy_rwsem is obtained with try so it doesn't + * interact with lockdep, however on destroy we have to sleep. This + * means if we have to destroy an object while holding a get on another + * object it triggers lockdep. Using one locking class per object type + * is a simple and reasonable way to avoid this. + */ + __init_rwsem(&obj->destroy_rwsem, "iommufd_object::destroy_rwsem", + &obj_keys[type]); refcount_set(&obj->users, 1); /* @@ -50,7 +60,7 @@ struct iommufd_object *_iommufd_object_alloc(struct iommufd_ctx *ictx, * before calling iommufd_object_finalize(). */ rc = xa_alloc(&ictx->objects, &obj->id, XA_ZERO_ENTRY, - xa_limit_32b, GFP_KERNEL_ACCOUNT); + xa_limit_31b, GFP_KERNEL_ACCOUNT); if (rc) goto out_free; return obj; @@ -95,7 +105,10 @@ void iommufd_object_abort(struct iommufd_ctx *ictx, struct iommufd_object *obj) void iommufd_object_abort_and_destroy(struct iommufd_ctx *ictx, struct iommufd_object *obj) { - iommufd_object_ops[obj->type].destroy(obj); + if (iommufd_object_ops[obj->type].abort) + iommufd_object_ops[obj->type].abort(obj); + else + iommufd_object_ops[obj->type].destroy(obj); iommufd_object_abort(ictx, obj); } @@ -223,6 +236,7 @@ static int iommufd_fops_open(struct inode *inode, struct file *filp) } xa_init_flags(&ictx->objects, XA_FLAGS_ALLOC1 | XA_FLAGS_ACCOUNT); + xa_init(&ictx->groups); ictx->file = filp; filp->private_data = ictx; return 0; @@ -258,6 +272,7 @@ static int iommufd_fops_release(struct inode *inode, struct file *filp) if (WARN_ON(!destroyed)) break; } + WARN_ON(!xa_empty(&ictx->groups)); kfree(ictx); return 0; } @@ -290,6 +305,7 @@ static int iommufd_option(struct iommufd_ucmd *ucmd) union ucmd_buffer { struct iommu_destroy destroy; + struct iommu_hwpt_alloc hwpt; struct iommu_ioas_alloc alloc; struct iommu_ioas_allow_iovas allow_iovas; struct iommu_ioas_copy ioas_copy; @@ -321,6 +337,8 @@ struct iommufd_ioctl_op { } static const struct iommufd_ioctl_op iommufd_ioctl_ops[] = { IOCTL_OP(IOMMU_DESTROY, iommufd_destroy, struct iommu_destroy, id), + IOCTL_OP(IOMMU_HWPT_ALLOC, iommufd_hwpt_alloc, struct iommu_hwpt_alloc, + __reserved), IOCTL_OP(IOMMU_IOAS_ALLOC, iommufd_ioas_alloc_ioctl, struct iommu_ioas_alloc, out_ioas_id), IOCTL_OP(IOMMU_IOAS_ALLOW_IOVAS, iommufd_ioas_allow_iovas, @@ -418,6 +436,30 @@ struct iommufd_ctx *iommufd_ctx_from_file(struct file *file) EXPORT_SYMBOL_NS_GPL(iommufd_ctx_from_file, IOMMUFD); /** + * iommufd_ctx_from_fd - Acquires a reference to the iommufd context + * @fd: File descriptor to obtain the reference from + * + * Returns a pointer to the iommufd_ctx, otherwise ERR_PTR. On success + * the caller is responsible to call iommufd_ctx_put(). + */ +struct iommufd_ctx *iommufd_ctx_from_fd(int fd) +{ + struct file *file; + + file = fget(fd); + if (!file) + return ERR_PTR(-EBADF); + + if (file->f_op != &iommufd_fops) { + fput(file); + return ERR_PTR(-EBADFD); + } + /* fget is the same as iommufd_ctx_get() */ + return file->private_data; +} +EXPORT_SYMBOL_NS_GPL(iommufd_ctx_from_fd, IOMMUFD); + +/** * iommufd_ctx_put - Put back a reference * @ictx: Context to put back */ @@ -439,6 +481,7 @@ static const struct iommufd_object_ops iommufd_object_ops[] = { }, [IOMMUFD_OBJ_HW_PAGETABLE] = { .destroy = iommufd_hw_pagetable_destroy, + .abort = iommufd_hw_pagetable_abort, }, #ifdef CONFIG_IOMMUFD_TEST [IOMMUFD_OBJ_SELFTEST] = { @@ -477,8 +520,14 @@ static int __init iommufd_init(void) if (ret) goto err_misc; } - iommufd_test_init(); + ret = iommufd_test_init(); + if (ret) + goto err_vfio_misc; return 0; + +err_vfio_misc: + if (IS_ENABLED(CONFIG_IOMMUFD_VFIO_CONTAINER)) + misc_deregister(&vfio_misc_dev); err_misc: misc_deregister(&iommu_misc_dev); return ret; @@ -499,5 +548,6 @@ module_exit(iommufd_exit); MODULE_ALIAS_MISCDEV(VFIO_MINOR); MODULE_ALIAS("devname:vfio/vfio"); #endif +MODULE_IMPORT_NS(IOMMUFD_INTERNAL); MODULE_DESCRIPTION("I/O Address Space Management for passthrough devices"); MODULE_LICENSE("GPL"); diff --git a/drivers/iommu/iommufd/selftest.c b/drivers/iommu/iommufd/selftest.c index 74c2076105d4..9223ff3f23f9 100644 --- a/drivers/iommu/iommufd/selftest.c +++ b/drivers/iommu/iommufd/selftest.c @@ -9,14 +9,17 @@ #include <linux/file.h> #include <linux/anon_inodes.h> #include <linux/fault-inject.h> +#include <linux/platform_device.h> #include <uapi/linux/iommufd.h> +#include "../iommu-priv.h" #include "io_pagetable.h" #include "iommufd_private.h" #include "iommufd_test.h" static DECLARE_FAULT_ATTR(fail_iommufd); static struct dentry *dbgfs_root; +static struct platform_device *selftest_iommu_dev; size_t iommufd_test_memory_limit = 65536; @@ -135,7 +138,7 @@ static struct iommu_domain *mock_domain_alloc(unsigned int iommu_domain_type) if (iommu_domain_type == IOMMU_DOMAIN_BLOCKED) return &mock_blocking_domain; - if (WARN_ON(iommu_domain_type != IOMMU_DOMAIN_UNMANAGED)) + if (iommu_domain_type != IOMMU_DOMAIN_UNMANAGED) return NULL; mock = kzalloc(sizeof(*mock), GFP_KERNEL); @@ -276,12 +279,22 @@ static void mock_domain_set_plaform_dma_ops(struct device *dev) */ } +static struct iommu_device mock_iommu_device = { +}; + +static struct iommu_device *mock_probe_device(struct device *dev) +{ + return &mock_iommu_device; +} + static const struct iommu_ops mock_ops = { .owner = THIS_MODULE, .pgsize_bitmap = MOCK_IO_PAGE_SIZE, .domain_alloc = mock_domain_alloc, .capable = mock_domain_capable, .set_platform_dma_ops = mock_domain_set_plaform_dma_ops, + .device_group = generic_device_group, + .probe_device = mock_probe_device, .default_domain_ops = &(struct iommu_domain_ops){ .free = mock_domain_free, @@ -292,10 +305,6 @@ static const struct iommu_ops mock_ops = { }, }; -static struct iommu_device mock_iommu_device = { - .ops = &mock_ops, -}; - static inline struct iommufd_hw_pagetable * get_md_pagetable(struct iommufd_ucmd *ucmd, u32 mockpt_id, struct mock_iommu_domain **mock) @@ -316,22 +325,29 @@ get_md_pagetable(struct iommufd_ucmd *ucmd, u32 mockpt_id, return hwpt; } -static struct bus_type iommufd_mock_bus_type = { - .name = "iommufd_mock", - .iommu_ops = &mock_ops, +struct mock_bus_type { + struct bus_type bus; + struct notifier_block nb; }; +static struct mock_bus_type iommufd_mock_bus_type = { + .bus = { + .name = "iommufd_mock", + }, +}; + +static atomic_t mock_dev_num; + static void mock_dev_release(struct device *dev) { struct mock_dev *mdev = container_of(dev, struct mock_dev, dev); + atomic_dec(&mock_dev_num); kfree(mdev); } static struct mock_dev *mock_dev_create(void) { - struct iommu_group *iommu_group; - struct dev_iommu *dev_iommu; struct mock_dev *mdev; int rc; @@ -341,51 +357,18 @@ static struct mock_dev *mock_dev_create(void) device_initialize(&mdev->dev); mdev->dev.release = mock_dev_release; - mdev->dev.bus = &iommufd_mock_bus_type; - - iommu_group = iommu_group_alloc(); - if (IS_ERR(iommu_group)) { - rc = PTR_ERR(iommu_group); - goto err_put; - } + mdev->dev.bus = &iommufd_mock_bus_type.bus; rc = dev_set_name(&mdev->dev, "iommufd_mock%u", - iommu_group_id(iommu_group)); + atomic_inc_return(&mock_dev_num)); if (rc) - goto err_group; - - /* - * The iommu core has no way to associate a single device with an iommu - * driver (heck currently it can't even support two iommu_drivers - * registering). Hack it together with an open coded dev_iommu_get(). - * Notice that the normal notifier triggered iommu release process also - * does not work here because this bus is not in iommu_buses. - */ - mdev->dev.iommu = kzalloc(sizeof(*dev_iommu), GFP_KERNEL); - if (!mdev->dev.iommu) { - rc = -ENOMEM; - goto err_group; - } - mutex_init(&mdev->dev.iommu->lock); - mdev->dev.iommu->iommu_dev = &mock_iommu_device; + goto err_put; rc = device_add(&mdev->dev); if (rc) - goto err_dev_iommu; - - rc = iommu_group_add_device(iommu_group, &mdev->dev); - if (rc) - goto err_del; - iommu_group_put(iommu_group); + goto err_put; return mdev; -err_del: - device_del(&mdev->dev); -err_dev_iommu: - kfree(mdev->dev.iommu); - mdev->dev.iommu = NULL; -err_group: - iommu_group_put(iommu_group); err_put: put_device(&mdev->dev); return ERR_PTR(rc); @@ -393,11 +376,7 @@ err_put: static void mock_dev_destroy(struct mock_dev *mdev) { - iommu_group_remove_device(&mdev->dev); - device_del(&mdev->dev); - kfree(mdev->dev.iommu); - mdev->dev.iommu = NULL; - put_device(&mdev->dev); + device_unregister(&mdev->dev); } bool iommufd_selftest_is_mock_dev(struct device *dev) @@ -443,9 +422,15 @@ static int iommufd_test_mock_domain(struct iommufd_ucmd *ucmd, /* Userspace must destroy the device_id to destroy the object */ cmd->mock_domain.out_hwpt_id = pt_id; cmd->mock_domain.out_stdev_id = sobj->obj.id; + cmd->mock_domain.out_idev_id = idev_id; + rc = iommufd_ucmd_respond(ucmd, sizeof(*cmd)); + if (rc) + goto out_detach; iommufd_object_finalize(ucmd->ictx, &sobj->obj); - return iommufd_ucmd_respond(ucmd, sizeof(*cmd)); + return 0; +out_detach: + iommufd_device_detach(idev); out_unbind: iommufd_device_unbind(idev); out_mdev: @@ -455,6 +440,42 @@ out_sobj: return rc; } +/* Replace the mock domain with a manually allocated hw_pagetable */ +static int iommufd_test_mock_domain_replace(struct iommufd_ucmd *ucmd, + unsigned int device_id, u32 pt_id, + struct iommu_test_cmd *cmd) +{ + struct iommufd_object *dev_obj; + struct selftest_obj *sobj; + int rc; + + /* + * Prefer to use the OBJ_SELFTEST because the destroy_rwsem will ensure + * it doesn't race with detach, which is not allowed. + */ + dev_obj = + iommufd_get_object(ucmd->ictx, device_id, IOMMUFD_OBJ_SELFTEST); + if (IS_ERR(dev_obj)) + return PTR_ERR(dev_obj); + + sobj = container_of(dev_obj, struct selftest_obj, obj); + if (sobj->type != TYPE_IDEV) { + rc = -EINVAL; + goto out_dev_obj; + } + + rc = iommufd_device_replace(sobj->idev.idev, &pt_id); + if (rc) + goto out_dev_obj; + + cmd->mock_domain_replace.pt_id = pt_id; + rc = iommufd_ucmd_respond(ucmd, sizeof(*cmd)); + +out_dev_obj: + iommufd_put_object(dev_obj); + return rc; +} + /* Add an additional reserved IOVA to the IOAS */ static int iommufd_test_add_reserved(struct iommufd_ucmd *ucmd, unsigned int mockpt_id, @@ -748,6 +769,22 @@ out_free_staccess: return rc; } +static int iommufd_test_access_replace_ioas(struct iommufd_ucmd *ucmd, + unsigned int access_id, + unsigned int ioas_id) +{ + struct selftest_access *staccess; + int rc; + + staccess = iommufd_access_get(access_id); + if (IS_ERR(staccess)) + return PTR_ERR(staccess); + + rc = iommufd_access_replace(staccess->access, ioas_id); + fput(staccess->file); + return rc; +} + /* Check that the pages in a page array match the pages in the user VA */ static int iommufd_test_check_pages(void __user *uptr, struct page **pages, size_t npages) @@ -948,6 +985,9 @@ int iommufd_test(struct iommufd_ucmd *ucmd) cmd->add_reserved.length); case IOMMU_TEST_OP_MOCK_DOMAIN: return iommufd_test_mock_domain(ucmd, cmd); + case IOMMU_TEST_OP_MOCK_DOMAIN_REPLACE: + return iommufd_test_mock_domain_replace( + ucmd, cmd->id, cmd->mock_domain_replace.pt_id, cmd); case IOMMU_TEST_OP_MD_CHECK_MAP: return iommufd_test_md_check_pa( ucmd, cmd->id, cmd->check_map.iova, @@ -960,6 +1000,9 @@ int iommufd_test(struct iommufd_ucmd *ucmd) case IOMMU_TEST_OP_CREATE_ACCESS: return iommufd_test_create_access(ucmd, cmd->id, cmd->create_access.flags); + case IOMMU_TEST_OP_ACCESS_REPLACE_IOAS: + return iommufd_test_access_replace_ioas( + ucmd, cmd->id, cmd->access_replace_ioas.ioas_id); case IOMMU_TEST_OP_ACCESS_PAGES: return iommufd_test_access_pages( ucmd, cmd->id, cmd->access_pages.iova, @@ -992,15 +1035,57 @@ bool iommufd_should_fail(void) return should_fail(&fail_iommufd, 1); } -void __init iommufd_test_init(void) +int __init iommufd_test_init(void) { + struct platform_device_info pdevinfo = { + .name = "iommufd_selftest_iommu", + }; + int rc; + dbgfs_root = fault_create_debugfs_attr("fail_iommufd", NULL, &fail_iommufd); - WARN_ON(bus_register(&iommufd_mock_bus_type)); + + selftest_iommu_dev = platform_device_register_full(&pdevinfo); + if (IS_ERR(selftest_iommu_dev)) { + rc = PTR_ERR(selftest_iommu_dev); + goto err_dbgfs; + } + + rc = bus_register(&iommufd_mock_bus_type.bus); + if (rc) + goto err_platform; + + rc = iommu_device_sysfs_add(&mock_iommu_device, + &selftest_iommu_dev->dev, NULL, "%s", + dev_name(&selftest_iommu_dev->dev)); + if (rc) + goto err_bus; + + rc = iommu_device_register_bus(&mock_iommu_device, &mock_ops, + &iommufd_mock_bus_type.bus, + &iommufd_mock_bus_type.nb); + if (rc) + goto err_sysfs; + return 0; + +err_sysfs: + iommu_device_sysfs_remove(&mock_iommu_device); +err_bus: + bus_unregister(&iommufd_mock_bus_type.bus); +err_platform: + platform_device_del(selftest_iommu_dev); +err_dbgfs: + debugfs_remove_recursive(dbgfs_root); + return rc; } void iommufd_test_exit(void) { + iommu_device_sysfs_remove(&mock_iommu_device); + iommu_device_unregister_bus(&mock_iommu_device, + &iommufd_mock_bus_type.bus, + &iommufd_mock_bus_type.nb); + bus_unregister(&iommufd_mock_bus_type.bus); + platform_device_del(selftest_iommu_dev); debugfs_remove_recursive(dbgfs_root); - bus_unregister(&iommufd_mock_bus_type); } diff --git a/drivers/s390/cio/vfio_ccw_ops.c b/drivers/s390/cio/vfio_ccw_ops.c index 5b53b94f13c7..cba4971618ff 100644 --- a/drivers/s390/cio/vfio_ccw_ops.c +++ b/drivers/s390/cio/vfio_ccw_ops.c @@ -632,6 +632,7 @@ static const struct vfio_device_ops vfio_ccw_dev_ops = { .bind_iommufd = vfio_iommufd_emulated_bind, .unbind_iommufd = vfio_iommufd_emulated_unbind, .attach_ioas = vfio_iommufd_emulated_attach_ioas, + .detach_ioas = vfio_iommufd_emulated_detach_ioas, }; struct mdev_driver vfio_ccw_mdev_driver = { diff --git a/drivers/s390/crypto/vfio_ap_ops.c b/drivers/s390/crypto/vfio_ap_ops.c index b441745b0418..2d3c3a79b687 100644 --- a/drivers/s390/crypto/vfio_ap_ops.c +++ b/drivers/s390/crypto/vfio_ap_ops.c @@ -1975,6 +1975,7 @@ static const struct vfio_device_ops vfio_ap_matrix_dev_ops = { .bind_iommufd = vfio_iommufd_emulated_bind, .unbind_iommufd = vfio_iommufd_emulated_unbind, .attach_ioas = vfio_iommufd_emulated_attach_ioas, + .detach_ioas = vfio_iommufd_emulated_detach_ioas, .request = vfio_ap_mdev_request }; diff --git a/drivers/vfio/Kconfig b/drivers/vfio/Kconfig index aba36f5be4ec..6bda6dbb4878 100644 --- a/drivers/vfio/Kconfig +++ b/drivers/vfio/Kconfig @@ -4,6 +4,8 @@ menuconfig VFIO select IOMMU_API depends on IOMMUFD || !IOMMUFD select INTERVAL_TREE + select VFIO_GROUP if SPAPR_TCE_IOMMU || IOMMUFD=n + select VFIO_DEVICE_CDEV if !VFIO_GROUP select VFIO_CONTAINER if IOMMUFD=n help VFIO provides a framework for secure userspace device drivers. @@ -12,9 +14,33 @@ menuconfig VFIO If you don't know what to do here, say N. if VFIO +config VFIO_DEVICE_CDEV + bool "Support for the VFIO cdev /dev/vfio/devices/vfioX" + depends on IOMMUFD && !SPAPR_TCE_IOMMU + default !VFIO_GROUP + help + The VFIO device cdev is another way for userspace to get device + access. Userspace gets device fd by opening device cdev under + /dev/vfio/devices/vfioX, and then bind the device fd with an iommufd + to set up secure DMA context for device access. This interface does + not support noiommu. + + If you don't know what to do here, say N. + +config VFIO_GROUP + bool "Support for the VFIO group /dev/vfio/$group_id" + default y + help + VFIO group support provides the traditional model for accessing + devices through VFIO and is used by the majority of userspace + applications and drivers making use of VFIO. + + If you don't know what to do here, say Y. + config VFIO_CONTAINER bool "Support for the VFIO container /dev/vfio/vfio" select VFIO_IOMMU_TYPE1 if MMU && (X86 || S390 || ARM || ARM64) + depends on VFIO_GROUP default y help The VFIO container is the classic interface to VFIO for establishing @@ -36,6 +62,7 @@ endif config VFIO_NOIOMMU bool "VFIO No-IOMMU support" + depends on VFIO_GROUP help VFIO is built on the ability to isolate devices using the IOMMU. Only with an IOMMU can userspace access to DMA capable devices be diff --git a/drivers/vfio/Makefile b/drivers/vfio/Makefile index 66f418aef5a9..c82ea032d352 100644 --- a/drivers/vfio/Makefile +++ b/drivers/vfio/Makefile @@ -2,8 +2,9 @@ obj-$(CONFIG_VFIO) += vfio.o vfio-y += vfio_main.o \ - group.o \ iova_bitmap.o +vfio-$(CONFIG_VFIO_DEVICE_CDEV) += device_cdev.o +vfio-$(CONFIG_VFIO_GROUP) += group.o vfio-$(CONFIG_IOMMUFD) += iommufd.o vfio-$(CONFIG_VFIO_CONTAINER) += container.o vfio-$(CONFIG_VFIO_VIRQFD) += virqfd.o diff --git a/drivers/vfio/device_cdev.c b/drivers/vfio/device_cdev.c new file mode 100644 index 000000000000..e75da0a70d1f --- /dev/null +++ b/drivers/vfio/device_cdev.c @@ -0,0 +1,228 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Copyright (c) 2023 Intel Corporation. + */ +#include <linux/vfio.h> +#include <linux/iommufd.h> + +#include "vfio.h" + +static dev_t device_devt; + +void vfio_init_device_cdev(struct vfio_device *device) +{ + device->device.devt = MKDEV(MAJOR(device_devt), device->index); + cdev_init(&device->cdev, &vfio_device_fops); + device->cdev.owner = THIS_MODULE; +} + +/* + * device access via the fd opened by this function is blocked until + * .open_device() is called successfully during BIND_IOMMUFD. + */ +int vfio_device_fops_cdev_open(struct inode *inode, struct file *filep) +{ + struct vfio_device *device = container_of(inode->i_cdev, + struct vfio_device, cdev); + struct vfio_device_file *df; + int ret; + + /* Paired with the put in vfio_device_fops_release() */ + if (!vfio_device_try_get_registration(device)) + return -ENODEV; + + df = vfio_allocate_device_file(device); + if (IS_ERR(df)) { + ret = PTR_ERR(df); + goto err_put_registration; + } + + filep->private_data = df; + + return 0; + +err_put_registration: + vfio_device_put_registration(device); + return ret; +} + +static void vfio_df_get_kvm_safe(struct vfio_device_file *df) +{ + spin_lock(&df->kvm_ref_lock); + vfio_device_get_kvm_safe(df->device, df->kvm); + spin_unlock(&df->kvm_ref_lock); +} + +long vfio_df_ioctl_bind_iommufd(struct vfio_device_file *df, + struct vfio_device_bind_iommufd __user *arg) +{ + struct vfio_device *device = df->device; + struct vfio_device_bind_iommufd bind; + unsigned long minsz; + int ret; + + static_assert(__same_type(arg->out_devid, df->devid)); + + minsz = offsetofend(struct vfio_device_bind_iommufd, out_devid); + + if (copy_from_user(&bind, arg, minsz)) + return -EFAULT; + + if (bind.argsz < minsz || bind.flags || bind.iommufd < 0) + return -EINVAL; + + /* BIND_IOMMUFD only allowed for cdev fds */ + if (df->group) + return -EINVAL; + + ret = vfio_device_block_group(device); + if (ret) + return ret; + + mutex_lock(&device->dev_set->lock); + /* one device cannot be bound twice */ + if (df->access_granted) { + ret = -EINVAL; + goto out_unlock; + } + + df->iommufd = iommufd_ctx_from_fd(bind.iommufd); + if (IS_ERR(df->iommufd)) { + ret = PTR_ERR(df->iommufd); + df->iommufd = NULL; + goto out_unlock; + } + + /* + * Before the device open, get the KVM pointer currently + * associated with the device file (if there is) and obtain + * a reference. This reference is held until device closed. + * Save the pointer in the device for use by drivers. + */ + vfio_df_get_kvm_safe(df); + + ret = vfio_df_open(df); + if (ret) + goto out_put_kvm; + + ret = copy_to_user(&arg->out_devid, &df->devid, + sizeof(df->devid)) ? -EFAULT : 0; + if (ret) + goto out_close_device; + + device->cdev_opened = true; + /* + * Paired with smp_load_acquire() in vfio_device_fops::ioctl/ + * read/write/mmap + */ + smp_store_release(&df->access_granted, true); + mutex_unlock(&device->dev_set->lock); + return 0; + +out_close_device: + vfio_df_close(df); +out_put_kvm: + vfio_device_put_kvm(device); + iommufd_ctx_put(df->iommufd); + df->iommufd = NULL; +out_unlock: + mutex_unlock(&device->dev_set->lock); + vfio_device_unblock_group(device); + return ret; +} + +void vfio_df_unbind_iommufd(struct vfio_device_file *df) +{ + struct vfio_device *device = df->device; + + /* + * In the time of close, there is no contention with another one + * changing this flag. So read df->access_granted without lock + * and no smp_load_acquire() is ok. + */ + if (!df->access_granted) + return; + + mutex_lock(&device->dev_set->lock); + vfio_df_close(df); + vfio_device_put_kvm(device); + iommufd_ctx_put(df->iommufd); + device->cdev_opened = false; + mutex_unlock(&device->dev_set->lock); + vfio_device_unblock_group(device); +} + +int vfio_df_ioctl_attach_pt(struct vfio_device_file *df, + struct vfio_device_attach_iommufd_pt __user *arg) +{ + struct vfio_device *device = df->device; + struct vfio_device_attach_iommufd_pt attach; + unsigned long minsz; + int ret; + + minsz = offsetofend(struct vfio_device_attach_iommufd_pt, pt_id); + + if (copy_from_user(&attach, arg, minsz)) + return -EFAULT; + + if (attach.argsz < minsz || attach.flags) + return -EINVAL; + + mutex_lock(&device->dev_set->lock); + ret = device->ops->attach_ioas(device, &attach.pt_id); + if (ret) + goto out_unlock; + + if (copy_to_user(&arg->pt_id, &attach.pt_id, sizeof(attach.pt_id))) { + ret = -EFAULT; + goto out_detach; + } + mutex_unlock(&device->dev_set->lock); + + return 0; + +out_detach: + device->ops->detach_ioas(device); +out_unlock: + mutex_unlock(&device->dev_set->lock); + return ret; +} + +int vfio_df_ioctl_detach_pt(struct vfio_device_file *df, + struct vfio_device_detach_iommufd_pt __user *arg) +{ + struct vfio_device *device = df->device; + struct vfio_device_detach_iommufd_pt detach; + unsigned long minsz; + + minsz = offsetofend(struct vfio_device_detach_iommufd_pt, flags); + + if (copy_from_user(&detach, arg, minsz)) + return -EFAULT; + + if (detach.argsz < minsz || detach.flags) + return -EINVAL; + + mutex_lock(&device->dev_set->lock); + device->ops->detach_ioas(device); + mutex_unlock(&device->dev_set->lock); + + return 0; +} + +static char *vfio_device_devnode(const struct device *dev, umode_t *mode) +{ + return kasprintf(GFP_KERNEL, "vfio/devices/%s", dev_name(dev)); +} + +int vfio_cdev_init(struct class *device_class) +{ + device_class->devnode = vfio_device_devnode; + return alloc_chrdev_region(&device_devt, 0, + MINORMASK + 1, "vfio-dev"); +} + +void vfio_cdev_cleanup(void) +{ + unregister_chrdev_region(device_devt, MINORMASK + 1); +} diff --git a/drivers/vfio/fsl-mc/vfio_fsl_mc.c b/drivers/vfio/fsl-mc/vfio_fsl_mc.c index f2140e94d41e..116358a8f1cf 100644 --- a/drivers/vfio/fsl-mc/vfio_fsl_mc.c +++ b/drivers/vfio/fsl-mc/vfio_fsl_mc.c @@ -593,6 +593,7 @@ static const struct vfio_device_ops vfio_fsl_mc_ops = { .bind_iommufd = vfio_iommufd_physical_bind, .unbind_iommufd = vfio_iommufd_physical_unbind, .attach_ioas = vfio_iommufd_physical_attach_ioas, + .detach_ioas = vfio_iommufd_physical_detach_ioas, }; static struct fsl_mc_driver vfio_fsl_mc_driver = { diff --git a/drivers/vfio/group.c b/drivers/vfio/group.c index fc75c1000d74..610a429c6191 100644 --- a/drivers/vfio/group.c +++ b/drivers/vfio/group.c @@ -160,17 +160,13 @@ out_unlock: static void vfio_device_group_get_kvm_safe(struct vfio_device *device) { spin_lock(&device->group->kvm_ref_lock); - if (!device->group->kvm) - goto unlock; - - _vfio_device_get_kvm_safe(device, device->group->kvm); - -unlock: + vfio_device_get_kvm_safe(device, device->group->kvm); spin_unlock(&device->group->kvm_ref_lock); } -static int vfio_device_group_open(struct vfio_device *device) +static int vfio_df_group_open(struct vfio_device_file *df) { + struct vfio_device *device = df->device; int ret; mutex_lock(&device->group->group_lock); @@ -190,24 +186,62 @@ static int vfio_device_group_open(struct vfio_device *device) if (device->open_count == 0) vfio_device_group_get_kvm_safe(device); - ret = vfio_device_open(device, device->group->iommufd); + df->iommufd = device->group->iommufd; + if (df->iommufd && vfio_device_is_noiommu(device) && device->open_count == 0) { + /* + * Require no compat ioas to be assigned to proceed. The basic + * statement is that the user cannot have done something that + * implies they expected translation to exist + */ + if (!capable(CAP_SYS_RAWIO) || + vfio_iommufd_device_has_compat_ioas(device, df->iommufd)) + ret = -EPERM; + else + ret = 0; + goto out_put_kvm; + } - if (device->open_count == 0) - vfio_device_put_kvm(device); + ret = vfio_df_open(df); + if (ret) + goto out_put_kvm; + + if (df->iommufd && device->open_count == 1) { + ret = vfio_iommufd_compat_attach_ioas(device, df->iommufd); + if (ret) + goto out_close_device; + } + + /* + * Paired with smp_load_acquire() in vfio_device_fops::ioctl/ + * read/write/mmap and vfio_file_has_device_access() + */ + smp_store_release(&df->access_granted, true); mutex_unlock(&device->dev_set->lock); + mutex_unlock(&device->group->group_lock); + return 0; +out_close_device: + vfio_df_close(df); +out_put_kvm: + df->iommufd = NULL; + if (device->open_count == 0) + vfio_device_put_kvm(device); + mutex_unlock(&device->dev_set->lock); out_unlock: mutex_unlock(&device->group->group_lock); return ret; } -void vfio_device_group_close(struct vfio_device *device) +void vfio_df_group_close(struct vfio_device_file *df) { + struct vfio_device *device = df->device; + mutex_lock(&device->group->group_lock); mutex_lock(&device->dev_set->lock); - vfio_device_close(device, device->group->iommufd); + vfio_df_close(df); + df->iommufd = NULL; if (device->open_count == 0) vfio_device_put_kvm(device); @@ -218,19 +252,28 @@ void vfio_device_group_close(struct vfio_device *device) static struct file *vfio_device_open_file(struct vfio_device *device) { + struct vfio_device_file *df; struct file *filep; int ret; - ret = vfio_device_group_open(device); - if (ret) + df = vfio_allocate_device_file(device); + if (IS_ERR(df)) { + ret = PTR_ERR(df); goto err_out; + } + + df->group = device->group; + + ret = vfio_df_group_open(df); + if (ret) + goto err_free; /* * We can't use anon_inode_getfd() because we need to modify * the f_mode flags directly to allow more than just ioctls */ filep = anon_inode_getfile("[vfio-device]", &vfio_device_fops, - device, O_RDWR); + df, O_RDWR); if (IS_ERR(filep)) { ret = PTR_ERR(filep); goto err_close_device; @@ -253,7 +296,9 @@ static struct file *vfio_device_open_file(struct vfio_device *device) return filep; err_close_device: - vfio_device_group_close(device); + vfio_df_group_close(df); +err_free: + kfree(df); err_out: return ERR_PTR(ret); } @@ -357,6 +402,33 @@ static long vfio_group_fops_unl_ioctl(struct file *filep, } } +int vfio_device_block_group(struct vfio_device *device) +{ + struct vfio_group *group = device->group; + int ret = 0; + + mutex_lock(&group->group_lock); + if (group->opened_file) { + ret = -EBUSY; + goto out_unlock; + } + + group->cdev_device_open_cnt++; + +out_unlock: + mutex_unlock(&group->group_lock); + return ret; +} + +void vfio_device_unblock_group(struct vfio_device *device) +{ + struct vfio_group *group = device->group; + + mutex_lock(&group->group_lock); + group->cdev_device_open_cnt--; + mutex_unlock(&group->group_lock); +} + static int vfio_group_fops_open(struct inode *inode, struct file *filep) { struct vfio_group *group = @@ -379,6 +451,11 @@ static int vfio_group_fops_open(struct inode *inode, struct file *filep) goto out_unlock; } + if (group->cdev_device_open_cnt) { + ret = -EBUSY; + goto out_unlock; + } + /* * Do we need multiple instances of the group open? Seems not. */ @@ -453,6 +530,7 @@ static void vfio_group_release(struct device *dev) mutex_destroy(&group->device_lock); mutex_destroy(&group->group_lock); WARN_ON(group->iommu_group); + WARN_ON(group->cdev_device_open_cnt); ida_free(&vfio.group_ida, MINOR(group->dev.devt)); kfree(group); } @@ -604,16 +682,6 @@ static struct vfio_group *vfio_group_find_or_alloc(struct device *dev) if (!iommu_group) return ERR_PTR(-EINVAL); - /* - * VFIO always sets IOMMU_CACHE because we offer no way for userspace to - * restore cache coherency. It has to be checked here because it is only - * valid for cases where we are using iommu groups. - */ - if (!device_iommu_capable(dev, IOMMU_CAP_CACHE_COHERENCY)) { - iommu_group_put(iommu_group); - return ERR_PTR(-EINVAL); - } - mutex_lock(&vfio.group_lock); group = vfio_group_find_from_iommu(iommu_group); if (group) { @@ -745,6 +813,15 @@ bool vfio_device_has_container(struct vfio_device *device) return device->group->container; } +struct vfio_group *vfio_group_from_file(struct file *file) +{ + struct vfio_group *group = file->private_data; + + if (file->f_op != &vfio_group_fops) + return NULL; + return group; +} + /** * vfio_file_iommu_group - Return the struct iommu_group for the vfio group file * @file: VFIO group file @@ -755,13 +832,13 @@ bool vfio_device_has_container(struct vfio_device *device) */ struct iommu_group *vfio_file_iommu_group(struct file *file) { - struct vfio_group *group = file->private_data; + struct vfio_group *group = vfio_group_from_file(file); struct iommu_group *iommu_group = NULL; if (!IS_ENABLED(CONFIG_SPAPR_TCE_IOMMU)) return NULL; - if (!vfio_file_is_group(file)) + if (!group) return NULL; mutex_lock(&group->group_lock); @@ -775,33 +852,20 @@ struct iommu_group *vfio_file_iommu_group(struct file *file) EXPORT_SYMBOL_GPL(vfio_file_iommu_group); /** - * vfio_file_is_group - True if the file is usable with VFIO aPIS + * vfio_file_is_group - True if the file is a vfio group file * @file: VFIO group file */ bool vfio_file_is_group(struct file *file) { - return file->f_op == &vfio_group_fops; + return vfio_group_from_file(file); } EXPORT_SYMBOL_GPL(vfio_file_is_group); -/** - * vfio_file_enforced_coherent - True if the DMA associated with the VFIO file - * is always CPU cache coherent - * @file: VFIO group file - * - * Enforced coherency means that the IOMMU ignores things like the PCIe no-snoop - * bit in DMA transactions. A return of false indicates that the user has - * rights to access additional instructions such as wbinvd on x86. - */ -bool vfio_file_enforced_coherent(struct file *file) +bool vfio_group_enforced_coherent(struct vfio_group *group) { - struct vfio_group *group = file->private_data; struct vfio_device *device; bool ret = true; - if (!vfio_file_is_group(file)) - return true; - /* * If the device does not have IOMMU_CAP_ENFORCE_CACHE_COHERENCY then * any domain later attached to it will also not support it. If the cap @@ -819,28 +883,13 @@ bool vfio_file_enforced_coherent(struct file *file) mutex_unlock(&group->device_lock); return ret; } -EXPORT_SYMBOL_GPL(vfio_file_enforced_coherent); -/** - * vfio_file_set_kvm - Link a kvm with VFIO drivers - * @file: VFIO group file - * @kvm: KVM to link - * - * When a VFIO device is first opened the KVM will be available in - * device->kvm if one was associated with the group. - */ -void vfio_file_set_kvm(struct file *file, struct kvm *kvm) +void vfio_group_set_kvm(struct vfio_group *group, struct kvm *kvm) { - struct vfio_group *group = file->private_data; - - if (!vfio_file_is_group(file)) - return; - spin_lock(&group->kvm_ref_lock); group->kvm = kvm; spin_unlock(&group->kvm_ref_lock); } -EXPORT_SYMBOL_GPL(vfio_file_set_kvm); /** * vfio_file_has_dev - True if the VFIO file is a handle for device @@ -851,9 +900,9 @@ EXPORT_SYMBOL_GPL(vfio_file_set_kvm); */ bool vfio_file_has_dev(struct file *file, struct vfio_device *device) { - struct vfio_group *group = file->private_data; + struct vfio_group *group = vfio_group_from_file(file); - if (!vfio_file_is_group(file)) + if (!group) return false; return group == device->group; diff --git a/drivers/vfio/iommufd.c b/drivers/vfio/iommufd.c index 88b00c501015..82eba6966fa5 100644 --- a/drivers/vfio/iommufd.c +++ b/drivers/vfio/iommufd.c @@ -10,53 +10,48 @@ MODULE_IMPORT_NS(IOMMUFD); MODULE_IMPORT_NS(IOMMUFD_VFIO); -int vfio_iommufd_bind(struct vfio_device *vdev, struct iommufd_ctx *ictx) +bool vfio_iommufd_device_has_compat_ioas(struct vfio_device *vdev, + struct iommufd_ctx *ictx) +{ + u32 ioas_id; + + return !iommufd_vfio_compat_ioas_get_id(ictx, &ioas_id); +} + +int vfio_df_iommufd_bind(struct vfio_device_file *df) +{ + struct vfio_device *vdev = df->device; + struct iommufd_ctx *ictx = df->iommufd; + + lockdep_assert_held(&vdev->dev_set->lock); + + return vdev->ops->bind_iommufd(vdev, ictx, &df->devid); +} + +int vfio_iommufd_compat_attach_ioas(struct vfio_device *vdev, + struct iommufd_ctx *ictx) { u32 ioas_id; - u32 device_id; int ret; lockdep_assert_held(&vdev->dev_set->lock); - if (vfio_device_is_noiommu(vdev)) { - if (!capable(CAP_SYS_RAWIO)) - return -EPERM; - - /* - * Require no compat ioas to be assigned to proceed. The basic - * statement is that the user cannot have done something that - * implies they expected translation to exist - */ - if (!iommufd_vfio_compat_ioas_get_id(ictx, &ioas_id)) - return -EPERM; + /* compat noiommu does not need to do ioas attach */ + if (vfio_device_is_noiommu(vdev)) return 0; - } - - ret = vdev->ops->bind_iommufd(vdev, ictx, &device_id); - if (ret) - return ret; ret = iommufd_vfio_compat_ioas_get_id(ictx, &ioas_id); if (ret) - goto err_unbind; - ret = vdev->ops->attach_ioas(vdev, &ioas_id); - if (ret) - goto err_unbind; - - /* - * The legacy path has no way to return the device id or the selected - * pt_id - */ - return 0; + return ret; -err_unbind: - if (vdev->ops->unbind_iommufd) - vdev->ops->unbind_iommufd(vdev); - return ret; + /* The legacy path has no way to return the selected pt_id */ + return vdev->ops->attach_ioas(vdev, &ioas_id); } -void vfio_iommufd_unbind(struct vfio_device *vdev) +void vfio_df_iommufd_unbind(struct vfio_device_file *df) { + struct vfio_device *vdev = df->device; + lockdep_assert_held(&vdev->dev_set->lock); if (vfio_device_is_noiommu(vdev)) @@ -66,6 +61,50 @@ void vfio_iommufd_unbind(struct vfio_device *vdev) vdev->ops->unbind_iommufd(vdev); } +struct iommufd_ctx *vfio_iommufd_device_ictx(struct vfio_device *vdev) +{ + if (vdev->iommufd_device) + return iommufd_device_to_ictx(vdev->iommufd_device); + return NULL; +} +EXPORT_SYMBOL_GPL(vfio_iommufd_device_ictx); + +static int vfio_iommufd_device_id(struct vfio_device *vdev) +{ + if (vdev->iommufd_device) + return iommufd_device_to_id(vdev->iommufd_device); + return -EINVAL; +} + +/* + * Return devid for a device. + * valid ID for the device that is owned by the ictx + * -ENOENT = device is owned but there is no ID + * -ENODEV or other error = device is not owned + */ +int vfio_iommufd_get_dev_id(struct vfio_device *vdev, struct iommufd_ctx *ictx) +{ + struct iommu_group *group; + int devid; + + if (vfio_iommufd_device_ictx(vdev) == ictx) + return vfio_iommufd_device_id(vdev); + + group = iommu_group_get(vdev->dev); + if (!group) + return -ENODEV; + + if (iommufd_ctx_has_group(ictx, group)) + devid = -ENOENT; + else + devid = -ENODEV; + + iommu_group_put(group); + + return devid; +} +EXPORT_SYMBOL_GPL(vfio_iommufd_get_dev_id); + /* * The physical standard ops mean that the iommufd_device is bound to the * physical device vdev->dev that was provided to vfio_init_group_dev(). Drivers @@ -101,7 +140,15 @@ int vfio_iommufd_physical_attach_ioas(struct vfio_device *vdev, u32 *pt_id) { int rc; - rc = iommufd_device_attach(vdev->iommufd_device, pt_id); + lockdep_assert_held(&vdev->dev_set->lock); + + if (WARN_ON(!vdev->iommufd_device)) + return -EINVAL; + + if (vdev->iommufd_attached) + rc = iommufd_device_replace(vdev->iommufd_device, pt_id); + else + rc = iommufd_device_attach(vdev->iommufd_device, pt_id); if (rc) return rc; vdev->iommufd_attached = true; @@ -109,6 +156,18 @@ int vfio_iommufd_physical_attach_ioas(struct vfio_device *vdev, u32 *pt_id) } EXPORT_SYMBOL_GPL(vfio_iommufd_physical_attach_ioas); +void vfio_iommufd_physical_detach_ioas(struct vfio_device *vdev) +{ + lockdep_assert_held(&vdev->dev_set->lock); + + if (WARN_ON(!vdev->iommufd_device) || !vdev->iommufd_attached) + return; + + iommufd_device_detach(vdev->iommufd_device); + vdev->iommufd_attached = false; +} +EXPORT_SYMBOL_GPL(vfio_iommufd_physical_detach_ioas); + /* * The emulated standard ops mean that vfio_device is going to use the * "mdev path" and will call vfio_pin_pages()/vfio_dma_rw(). Drivers using this @@ -164,11 +223,25 @@ int vfio_iommufd_emulated_attach_ioas(struct vfio_device *vdev, u32 *pt_id) lockdep_assert_held(&vdev->dev_set->lock); if (vdev->iommufd_attached) - return -EBUSY; - rc = iommufd_access_attach(vdev->iommufd_access, *pt_id); + rc = iommufd_access_replace(vdev->iommufd_access, *pt_id); + else + rc = iommufd_access_attach(vdev->iommufd_access, *pt_id); if (rc) return rc; vdev->iommufd_attached = true; return 0; } EXPORT_SYMBOL_GPL(vfio_iommufd_emulated_attach_ioas); + +void vfio_iommufd_emulated_detach_ioas(struct vfio_device *vdev) +{ + lockdep_assert_held(&vdev->dev_set->lock); + + if (WARN_ON(!vdev->iommufd_access) || + !vdev->iommufd_attached) + return; + + iommufd_access_detach(vdev->iommufd_access); + vdev->iommufd_attached = false; +} +EXPORT_SYMBOL_GPL(vfio_iommufd_emulated_detach_ioas); diff --git a/drivers/vfio/pci/hisilicon/hisi_acc_vfio_pci.c b/drivers/vfio/pci/hisilicon/hisi_acc_vfio_pci.c index a117eaf21c14..b2f9778c8366 100644 --- a/drivers/vfio/pci/hisilicon/hisi_acc_vfio_pci.c +++ b/drivers/vfio/pci/hisilicon/hisi_acc_vfio_pci.c @@ -1373,6 +1373,7 @@ static const struct vfio_device_ops hisi_acc_vfio_pci_migrn_ops = { .bind_iommufd = vfio_iommufd_physical_bind, .unbind_iommufd = vfio_iommufd_physical_unbind, .attach_ioas = vfio_iommufd_physical_attach_ioas, + .detach_ioas = vfio_iommufd_physical_detach_ioas, }; static const struct vfio_device_ops hisi_acc_vfio_pci_ops = { @@ -1391,6 +1392,7 @@ static const struct vfio_device_ops hisi_acc_vfio_pci_ops = { .bind_iommufd = vfio_iommufd_physical_bind, .unbind_iommufd = vfio_iommufd_physical_unbind, .attach_ioas = vfio_iommufd_physical_attach_ioas, + .detach_ioas = vfio_iommufd_physical_detach_ioas, }; static int hisi_acc_vfio_pci_probe(struct pci_dev *pdev, const struct pci_device_id *id) diff --git a/drivers/vfio/pci/mlx5/main.c b/drivers/vfio/pci/mlx5/main.c index d95fd382814c..42ec574a8622 100644 --- a/drivers/vfio/pci/mlx5/main.c +++ b/drivers/vfio/pci/mlx5/main.c @@ -1320,6 +1320,7 @@ static const struct vfio_device_ops mlx5vf_pci_ops = { .bind_iommufd = vfio_iommufd_physical_bind, .unbind_iommufd = vfio_iommufd_physical_unbind, .attach_ioas = vfio_iommufd_physical_attach_ioas, + .detach_ioas = vfio_iommufd_physical_detach_ioas, }; static int mlx5vf_pci_probe(struct pci_dev *pdev, diff --git a/drivers/vfio/pci/vfio_pci.c b/drivers/vfio/pci/vfio_pci.c index 29091ee2e984..cb5b7f865d58 100644 --- a/drivers/vfio/pci/vfio_pci.c +++ b/drivers/vfio/pci/vfio_pci.c @@ -141,6 +141,7 @@ static const struct vfio_device_ops vfio_pci_ops = { .bind_iommufd = vfio_iommufd_physical_bind, .unbind_iommufd = vfio_iommufd_physical_unbind, .attach_ioas = vfio_iommufd_physical_attach_ioas, + .detach_ioas = vfio_iommufd_physical_detach_ioas, }; static int vfio_pci_probe(struct pci_dev *pdev, const struct pci_device_id *id) diff --git a/drivers/vfio/pci/vfio_pci_core.c b/drivers/vfio/pci/vfio_pci_core.c index 20d7b69ea6ff..65cbada3ec13 100644 --- a/drivers/vfio/pci/vfio_pci_core.c +++ b/drivers/vfio/pci/vfio_pci_core.c @@ -27,6 +27,7 @@ #include <linux/vgaarb.h> #include <linux/nospec.h> #include <linux/sched/mm.h> +#include <linux/iommufd.h> #if IS_ENABLED(CONFIG_EEH) #include <asm/eeh.h> #endif @@ -180,7 +181,8 @@ no_mmap: struct vfio_pci_group_info; static void vfio_pci_dev_set_try_reset(struct vfio_device_set *dev_set); static int vfio_pci_dev_set_hot_reset(struct vfio_device_set *dev_set, - struct vfio_pci_group_info *groups); + struct vfio_pci_group_info *groups, + struct iommufd_ctx *iommufd_ctx); /* * INTx masking requires the ability to disable INTx signaling via PCI_COMMAND @@ -776,29 +778,65 @@ static int vfio_pci_count_devs(struct pci_dev *pdev, void *data) } struct vfio_pci_fill_info { - int max; - int cur; - struct vfio_pci_dependent_device *devices; + struct vfio_pci_dependent_device __user *devices; + struct vfio_pci_dependent_device __user *devices_end; + struct vfio_device *vdev; + u32 count; + u32 flags; }; static int vfio_pci_fill_devs(struct pci_dev *pdev, void *data) { + struct vfio_pci_dependent_device info = { + .segment = pci_domain_nr(pdev->bus), + .bus = pdev->bus->number, + .devfn = pdev->devfn, + }; struct vfio_pci_fill_info *fill = data; - struct iommu_group *iommu_group; - if (fill->cur == fill->max) - return -EAGAIN; /* Something changed, try again */ + fill->count++; + if (fill->devices >= fill->devices_end) + return 0; + + if (fill->flags & VFIO_PCI_HOT_RESET_FLAG_DEV_ID) { + struct iommufd_ctx *iommufd = vfio_iommufd_device_ictx(fill->vdev); + struct vfio_device_set *dev_set = fill->vdev->dev_set; + struct vfio_device *vdev; + + /* + * hot-reset requires all affected devices be represented in + * the dev_set. + */ + vdev = vfio_find_device_in_devset(dev_set, &pdev->dev); + if (!vdev) { + info.devid = VFIO_PCI_DEVID_NOT_OWNED; + } else { + int id = vfio_iommufd_get_dev_id(vdev, iommufd); + + if (id > 0) + info.devid = id; + else if (id == -ENOENT) + info.devid = VFIO_PCI_DEVID_OWNED; + else + info.devid = VFIO_PCI_DEVID_NOT_OWNED; + } + /* If devid is VFIO_PCI_DEVID_NOT_OWNED, clear owned flag. */ + if (info.devid == VFIO_PCI_DEVID_NOT_OWNED) + fill->flags &= ~VFIO_PCI_HOT_RESET_FLAG_DEV_ID_OWNED; + } else { + struct iommu_group *iommu_group; - iommu_group = iommu_group_get(&pdev->dev); - if (!iommu_group) - return -EPERM; /* Cannot reset non-isolated devices */ + iommu_group = iommu_group_get(&pdev->dev); + if (!iommu_group) + return -EPERM; /* Cannot reset non-isolated devices */ - fill->devices[fill->cur].group_id = iommu_group_id(iommu_group); - fill->devices[fill->cur].segment = pci_domain_nr(pdev->bus); - fill->devices[fill->cur].bus = pdev->bus->number; - fill->devices[fill->cur].devfn = pdev->devfn; - fill->cur++; - iommu_group_put(iommu_group); + info.group_id = iommu_group_id(iommu_group); + iommu_group_put(iommu_group); + } + + if (copy_to_user(fill->devices, &info, sizeof(info))) + return -EFAULT; + fill->devices++; return 0; } @@ -1228,8 +1266,7 @@ static int vfio_pci_ioctl_get_pci_hot_reset_info( unsigned long minsz = offsetofend(struct vfio_pci_hot_reset_info, count); struct vfio_pci_hot_reset_info hdr; - struct vfio_pci_fill_info fill = { 0 }; - struct vfio_pci_dependent_device *devices = NULL; + struct vfio_pci_fill_info fill = {}; bool slot = false; int ret = 0; @@ -1247,78 +1284,42 @@ static int vfio_pci_ioctl_get_pci_hot_reset_info( else if (pci_probe_reset_bus(vdev->pdev->bus)) return -ENODEV; - /* How many devices are affected? */ - ret = vfio_pci_for_each_slot_or_bus(vdev->pdev, vfio_pci_count_devs, - &fill.max, slot); - if (ret) - return ret; - - WARN_ON(!fill.max); /* Should always be at least one */ - - /* - * If there's enough space, fill it now, otherwise return -ENOSPC and - * the number of devices affected. - */ - if (hdr.argsz < sizeof(hdr) + (fill.max * sizeof(*devices))) { - ret = -ENOSPC; - hdr.count = fill.max; - goto reset_info_exit; - } - - devices = kcalloc(fill.max, sizeof(*devices), GFP_KERNEL); - if (!devices) - return -ENOMEM; + fill.devices = arg->devices; + fill.devices_end = arg->devices + + (hdr.argsz - sizeof(hdr)) / sizeof(arg->devices[0]); + fill.vdev = &vdev->vdev; - fill.devices = devices; + if (vfio_device_cdev_opened(&vdev->vdev)) + fill.flags |= VFIO_PCI_HOT_RESET_FLAG_DEV_ID | + VFIO_PCI_HOT_RESET_FLAG_DEV_ID_OWNED; + mutex_lock(&vdev->vdev.dev_set->lock); ret = vfio_pci_for_each_slot_or_bus(vdev->pdev, vfio_pci_fill_devs, &fill, slot); + mutex_unlock(&vdev->vdev.dev_set->lock); + if (ret) + return ret; - /* - * If a device was removed between counting and filling, we may come up - * short of fill.max. If a device was added, we'll have a return of - * -EAGAIN above. - */ - if (!ret) - hdr.count = fill.cur; - -reset_info_exit: + hdr.count = fill.count; + hdr.flags = fill.flags; if (copy_to_user(arg, &hdr, minsz)) - ret = -EFAULT; - - if (!ret) { - if (copy_to_user(&arg->devices, devices, - hdr.count * sizeof(*devices))) - ret = -EFAULT; - } + return -EFAULT; - kfree(devices); - return ret; + if (fill.count > fill.devices - arg->devices) + return -ENOSPC; + return 0; } -static int vfio_pci_ioctl_pci_hot_reset(struct vfio_pci_core_device *vdev, - struct vfio_pci_hot_reset __user *arg) +static int +vfio_pci_ioctl_pci_hot_reset_groups(struct vfio_pci_core_device *vdev, + int array_count, bool slot, + struct vfio_pci_hot_reset __user *arg) { - unsigned long minsz = offsetofend(struct vfio_pci_hot_reset, count); - struct vfio_pci_hot_reset hdr; int32_t *group_fds; struct file **files; struct vfio_pci_group_info info; - bool slot = false; int file_idx, count = 0, ret = 0; - if (copy_from_user(&hdr, arg, minsz)) - return -EFAULT; - - if (hdr.argsz < minsz || hdr.flags) - return -EINVAL; - - /* Can we do a slot or bus reset or neither? */ - if (!pci_probe_reset_slot(vdev->pdev->slot)) - slot = true; - else if (pci_probe_reset_bus(vdev->pdev->bus)) - return -ENODEV; - /* * We can't let userspace give us an arbitrarily large buffer to copy, * so verify how many we think there could be. Note groups can have @@ -1329,12 +1330,11 @@ static int vfio_pci_ioctl_pci_hot_reset(struct vfio_pci_core_device *vdev, if (ret) return ret; - /* Somewhere between 1 and count is OK */ - if (!hdr.count || hdr.count > count) + if (array_count > count) return -EINVAL; - group_fds = kcalloc(hdr.count, sizeof(*group_fds), GFP_KERNEL); - files = kcalloc(hdr.count, sizeof(*files), GFP_KERNEL); + group_fds = kcalloc(array_count, sizeof(*group_fds), GFP_KERNEL); + files = kcalloc(array_count, sizeof(*files), GFP_KERNEL); if (!group_fds || !files) { kfree(group_fds); kfree(files); @@ -1342,18 +1342,17 @@ static int vfio_pci_ioctl_pci_hot_reset(struct vfio_pci_core_device *vdev, } if (copy_from_user(group_fds, arg->group_fds, - hdr.count * sizeof(*group_fds))) { + array_count * sizeof(*group_fds))) { kfree(group_fds); kfree(files); return -EFAULT; } /* - * For each group_fd, get the group through the vfio external user - * interface and store the group and iommu ID. This ensures the group - * is held across the reset. + * Get the group file for each fd to ensure the group is held across + * the reset */ - for (file_idx = 0; file_idx < hdr.count; file_idx++) { + for (file_idx = 0; file_idx < array_count; file_idx++) { struct file *file = fget(group_fds[file_idx]); if (!file) { @@ -1377,10 +1376,10 @@ static int vfio_pci_ioctl_pci_hot_reset(struct vfio_pci_core_device *vdev, if (ret) goto hot_reset_release; - info.count = hdr.count; + info.count = array_count; info.files = files; - ret = vfio_pci_dev_set_hot_reset(vdev->vdev.dev_set, &info); + ret = vfio_pci_dev_set_hot_reset(vdev->vdev.dev_set, &info, NULL); hot_reset_release: for (file_idx--; file_idx >= 0; file_idx--) @@ -1390,6 +1389,36 @@ hot_reset_release: return ret; } +static int vfio_pci_ioctl_pci_hot_reset(struct vfio_pci_core_device *vdev, + struct vfio_pci_hot_reset __user *arg) +{ + unsigned long minsz = offsetofend(struct vfio_pci_hot_reset, count); + struct vfio_pci_hot_reset hdr; + bool slot = false; + + if (copy_from_user(&hdr, arg, minsz)) + return -EFAULT; + + if (hdr.argsz < minsz || hdr.flags) + return -EINVAL; + + /* zero-length array is only for cdev opened devices */ + if (!!hdr.count == vfio_device_cdev_opened(&vdev->vdev)) + return -EINVAL; + + /* Can we do a slot or bus reset or neither? */ + if (!pci_probe_reset_slot(vdev->pdev->slot)) + slot = true; + else if (pci_probe_reset_bus(vdev->pdev->bus)) + return -ENODEV; + + if (hdr.count) + return vfio_pci_ioctl_pci_hot_reset_groups(vdev, hdr.count, slot, arg); + + return vfio_pci_dev_set_hot_reset(vdev->vdev.dev_set, NULL, + vfio_iommufd_device_ictx(&vdev->vdev)); +} + static int vfio_pci_ioctl_ioeventfd(struct vfio_pci_core_device *vdev, struct vfio_device_ioeventfd __user *arg) { @@ -2355,13 +2384,16 @@ const struct pci_error_handlers vfio_pci_core_err_handlers = { }; EXPORT_SYMBOL_GPL(vfio_pci_core_err_handlers); -static bool vfio_dev_in_groups(struct vfio_pci_core_device *vdev, +static bool vfio_dev_in_groups(struct vfio_device *vdev, struct vfio_pci_group_info *groups) { unsigned int i; + if (!groups) + return false; + for (i = 0; i < groups->count; i++) - if (vfio_file_has_dev(groups->files[i], &vdev->vdev)) + if (vfio_file_has_dev(groups->files[i], vdev)) return true; return false; } @@ -2369,12 +2401,8 @@ static bool vfio_dev_in_groups(struct vfio_pci_core_device *vdev, static int vfio_pci_is_device_in_set(struct pci_dev *pdev, void *data) { struct vfio_device_set *dev_set = data; - struct vfio_device *cur; - list_for_each_entry(cur, &dev_set->device_list, dev_set_list) - if (cur->dev == &pdev->dev) - return 0; - return -EBUSY; + return vfio_find_device_in_devset(dev_set, &pdev->dev) ? 0 : -ENODEV; } /* @@ -2441,7 +2469,8 @@ unwind: * get each memory_lock. */ static int vfio_pci_dev_set_hot_reset(struct vfio_device_set *dev_set, - struct vfio_pci_group_info *groups) + struct vfio_pci_group_info *groups, + struct iommufd_ctx *iommufd_ctx) { struct vfio_pci_core_device *cur_mem; struct vfio_pci_core_device *cur_vma; @@ -2471,11 +2500,38 @@ static int vfio_pci_dev_set_hot_reset(struct vfio_device_set *dev_set, goto err_unlock; list_for_each_entry(cur_vma, &dev_set->device_list, vdev.dev_set_list) { + bool owned; + /* - * Test whether all the affected devices are contained by the - * set of groups provided by the user. + * Test whether all the affected devices can be reset by the + * user. + * + * If called from a group opened device and the user provides + * a set of groups, all the devices in the dev_set should be + * contained by the set of groups provided by the user. + * + * If called from a cdev opened device and the user provides + * a zero-length array, all the devices in the dev_set must + * be bound to the same iommufd_ctx as the input iommufd_ctx. + * If there is any device that has not been bound to any + * iommufd_ctx yet, check if its iommu_group has any device + * bound to the input iommufd_ctx. Such devices can be + * considered owned by the input iommufd_ctx as the device + * cannot be owned by another iommufd_ctx when its iommu_group + * is owned. + * + * Otherwise, reset is not allowed. */ - if (!vfio_dev_in_groups(cur_vma, groups)) { + if (iommufd_ctx) { + int devid = vfio_iommufd_get_dev_id(&cur_vma->vdev, + iommufd_ctx); + + owned = (devid > 0 || devid == -ENOENT); + } else { + owned = vfio_dev_in_groups(&cur_vma->vdev, groups); + } + + if (!owned) { ret = -EINVAL; goto err_undo; } diff --git a/drivers/vfio/platform/vfio_amba.c b/drivers/vfio/platform/vfio_amba.c index 83fe54015595..6464b3939ebc 100644 --- a/drivers/vfio/platform/vfio_amba.c +++ b/drivers/vfio/platform/vfio_amba.c @@ -119,6 +119,7 @@ static const struct vfio_device_ops vfio_amba_ops = { .bind_iommufd = vfio_iommufd_physical_bind, .unbind_iommufd = vfio_iommufd_physical_unbind, .attach_ioas = vfio_iommufd_physical_attach_ioas, + .detach_ioas = vfio_iommufd_physical_detach_ioas, }; static const struct amba_id pl330_ids[] = { diff --git a/drivers/vfio/platform/vfio_platform.c b/drivers/vfio/platform/vfio_platform.c index 22a1efca32a8..8cf22fa65baa 100644 --- a/drivers/vfio/platform/vfio_platform.c +++ b/drivers/vfio/platform/vfio_platform.c @@ -108,6 +108,7 @@ static const struct vfio_device_ops vfio_platform_ops = { .bind_iommufd = vfio_iommufd_physical_bind, .unbind_iommufd = vfio_iommufd_physical_unbind, .attach_ioas = vfio_iommufd_physical_attach_ioas, + .detach_ioas = vfio_iommufd_physical_detach_ioas, }; static struct platform_driver vfio_platform_driver = { diff --git a/drivers/vfio/vfio.h b/drivers/vfio/vfio.h index 7b19c621e0e6..307e3f29b527 100644 --- a/drivers/vfio/vfio.h +++ b/drivers/vfio/vfio.h @@ -16,14 +16,32 @@ struct iommufd_ctx; struct iommu_group; struct vfio_container; +struct vfio_device_file { + struct vfio_device *device; + struct vfio_group *group; + + u8 access_granted; + u32 devid; /* only valid when iommufd is valid */ + spinlock_t kvm_ref_lock; /* protect kvm field */ + struct kvm *kvm; + struct iommufd_ctx *iommufd; /* protected by struct vfio_device_set::lock */ +}; + void vfio_device_put_registration(struct vfio_device *device); bool vfio_device_try_get_registration(struct vfio_device *device); -int vfio_device_open(struct vfio_device *device, struct iommufd_ctx *iommufd); -void vfio_device_close(struct vfio_device *device, - struct iommufd_ctx *iommufd); +int vfio_df_open(struct vfio_device_file *df); +void vfio_df_close(struct vfio_device_file *df); +struct vfio_device_file * +vfio_allocate_device_file(struct vfio_device *device); extern const struct file_operations vfio_device_fops; +#ifdef CONFIG_VFIO_NOIOMMU +extern bool vfio_noiommu __read_mostly; +#else +enum { vfio_noiommu = false }; +#endif + enum vfio_group_type { /* * Physical device with IOMMU backing. @@ -48,6 +66,7 @@ enum vfio_group_type { VFIO_NO_IOMMU, }; +#if IS_ENABLED(CONFIG_VFIO_GROUP) struct vfio_group { struct device dev; struct cdev cdev; @@ -74,8 +93,11 @@ struct vfio_group { struct blocking_notifier_head notifier; struct iommufd_ctx *iommufd; spinlock_t kvm_ref_lock; + unsigned int cdev_device_open_cnt; }; +int vfio_device_block_group(struct vfio_device *device); +void vfio_device_unblock_group(struct vfio_device *device); int vfio_device_set_group(struct vfio_device *device, enum vfio_group_type type); void vfio_device_remove_group(struct vfio_device *device); @@ -83,7 +105,10 @@ void vfio_device_group_register(struct vfio_device *device); void vfio_device_group_unregister(struct vfio_device *device); int vfio_device_group_use_iommu(struct vfio_device *device); void vfio_device_group_unuse_iommu(struct vfio_device *device); -void vfio_device_group_close(struct vfio_device *device); +void vfio_df_group_close(struct vfio_device_file *df); +struct vfio_group *vfio_group_from_file(struct file *file); +bool vfio_group_enforced_coherent(struct vfio_group *group); +void vfio_group_set_kvm(struct vfio_group *group, struct kvm *kvm); bool vfio_device_has_container(struct vfio_device *device); int __init vfio_group_init(void); void vfio_group_cleanup(void); @@ -93,6 +118,82 @@ static inline bool vfio_device_is_noiommu(struct vfio_device *vdev) return IS_ENABLED(CONFIG_VFIO_NOIOMMU) && vdev->group->type == VFIO_NO_IOMMU; } +#else +struct vfio_group; + +static inline int vfio_device_block_group(struct vfio_device *device) +{ + return 0; +} + +static inline void vfio_device_unblock_group(struct vfio_device *device) +{ +} + +static inline int vfio_device_set_group(struct vfio_device *device, + enum vfio_group_type type) +{ + return 0; +} + +static inline void vfio_device_remove_group(struct vfio_device *device) +{ +} + +static inline void vfio_device_group_register(struct vfio_device *device) +{ +} + +static inline void vfio_device_group_unregister(struct vfio_device *device) +{ +} + +static inline int vfio_device_group_use_iommu(struct vfio_device *device) +{ + return -EOPNOTSUPP; +} + +static inline void vfio_device_group_unuse_iommu(struct vfio_device *device) +{ +} + +static inline void vfio_df_group_close(struct vfio_device_file *df) +{ +} + +static inline struct vfio_group *vfio_group_from_file(struct file *file) +{ + return NULL; +} + +static inline bool vfio_group_enforced_coherent(struct vfio_group *group) +{ + return true; +} + +static inline void vfio_group_set_kvm(struct vfio_group *group, struct kvm *kvm) +{ +} + +static inline bool vfio_device_has_container(struct vfio_device *device) +{ + return false; +} + +static inline int __init vfio_group_init(void) +{ + return 0; +} + +static inline void vfio_group_cleanup(void) +{ +} + +static inline bool vfio_device_is_noiommu(struct vfio_device *vdev) +{ + return false; +} +#endif /* CONFIG_VFIO_GROUP */ #if IS_ENABLED(CONFIG_VFIO_CONTAINER) /** @@ -217,20 +318,109 @@ static inline void vfio_container_cleanup(void) #endif #if IS_ENABLED(CONFIG_IOMMUFD) -int vfio_iommufd_bind(struct vfio_device *device, struct iommufd_ctx *ictx); -void vfio_iommufd_unbind(struct vfio_device *device); +bool vfio_iommufd_device_has_compat_ioas(struct vfio_device *vdev, + struct iommufd_ctx *ictx); +int vfio_df_iommufd_bind(struct vfio_device_file *df); +void vfio_df_iommufd_unbind(struct vfio_device_file *df); +int vfio_iommufd_compat_attach_ioas(struct vfio_device *device, + struct iommufd_ctx *ictx); #else -static inline int vfio_iommufd_bind(struct vfio_device *device, +static inline bool +vfio_iommufd_device_has_compat_ioas(struct vfio_device *vdev, struct iommufd_ctx *ictx) { + return false; +} + +static inline int vfio_df_iommufd_bind(struct vfio_device_file *fd) +{ return -EOPNOTSUPP; } -static inline void vfio_iommufd_unbind(struct vfio_device *device) +static inline void vfio_df_iommufd_unbind(struct vfio_device_file *df) { } + +static inline int +vfio_iommufd_compat_attach_ioas(struct vfio_device *device, + struct iommufd_ctx *ictx) +{ + return -EOPNOTSUPP; +} #endif +int vfio_df_ioctl_attach_pt(struct vfio_device_file *df, + struct vfio_device_attach_iommufd_pt __user *arg); +int vfio_df_ioctl_detach_pt(struct vfio_device_file *df, + struct vfio_device_detach_iommufd_pt __user *arg); + +#if IS_ENABLED(CONFIG_VFIO_DEVICE_CDEV) +void vfio_init_device_cdev(struct vfio_device *device); + +static inline int vfio_device_add(struct vfio_device *device) +{ + /* cdev does not support noiommu device */ + if (vfio_device_is_noiommu(device)) + return device_add(&device->device); + vfio_init_device_cdev(device); + return cdev_device_add(&device->cdev, &device->device); +} + +static inline void vfio_device_del(struct vfio_device *device) +{ + if (vfio_device_is_noiommu(device)) + device_del(&device->device); + else + cdev_device_del(&device->cdev, &device->device); +} + +int vfio_device_fops_cdev_open(struct inode *inode, struct file *filep); +long vfio_df_ioctl_bind_iommufd(struct vfio_device_file *df, + struct vfio_device_bind_iommufd __user *arg); +void vfio_df_unbind_iommufd(struct vfio_device_file *df); +int vfio_cdev_init(struct class *device_class); +void vfio_cdev_cleanup(void); +#else +static inline void vfio_init_device_cdev(struct vfio_device *device) +{ +} + +static inline int vfio_device_add(struct vfio_device *device) +{ + return device_add(&device->device); +} + +static inline void vfio_device_del(struct vfio_device *device) +{ + device_del(&device->device); +} + +static inline int vfio_device_fops_cdev_open(struct inode *inode, + struct file *filep) +{ + return 0; +} + +static inline long vfio_df_ioctl_bind_iommufd(struct vfio_device_file *df, + struct vfio_device_bind_iommufd __user *arg) +{ + return -ENOTTY; +} + +static inline void vfio_df_unbind_iommufd(struct vfio_device_file *df) +{ +} + +static inline int vfio_cdev_init(struct class *device_class) +{ + return 0; +} + +static inline void vfio_cdev_cleanup(void) +{ +} +#endif /* CONFIG_VFIO_DEVICE_CDEV */ + #if IS_ENABLED(CONFIG_VFIO_VIRQFD) int __init vfio_virqfd_init(void); void vfio_virqfd_exit(void); @@ -244,18 +434,12 @@ static inline void vfio_virqfd_exit(void) } #endif -#ifdef CONFIG_VFIO_NOIOMMU -extern bool vfio_noiommu __read_mostly; -#else -enum { vfio_noiommu = false }; -#endif - #ifdef CONFIG_HAVE_KVM -void _vfio_device_get_kvm_safe(struct vfio_device *device, struct kvm *kvm); +void vfio_device_get_kvm_safe(struct vfio_device *device, struct kvm *kvm); void vfio_device_put_kvm(struct vfio_device *device); #else -static inline void _vfio_device_get_kvm_safe(struct vfio_device *device, - struct kvm *kvm) +static inline void vfio_device_get_kvm_safe(struct vfio_device *device, + struct kvm *kvm) { } diff --git a/drivers/vfio/vfio_main.c b/drivers/vfio/vfio_main.c index f0ca33b2e1df..0da8ed81a97d 100644 --- a/drivers/vfio/vfio_main.c +++ b/drivers/vfio/vfio_main.c @@ -141,6 +141,21 @@ unsigned int vfio_device_set_open_count(struct vfio_device_set *dev_set) } EXPORT_SYMBOL_GPL(vfio_device_set_open_count); +struct vfio_device * +vfio_find_device_in_devset(struct vfio_device_set *dev_set, + struct device *dev) +{ + struct vfio_device *cur; + + lockdep_assert_held(&dev_set->lock); + + list_for_each_entry(cur, &dev_set->device_list, dev_set_list) + if (cur->dev == dev) + return cur; + return NULL; +} +EXPORT_SYMBOL_GPL(vfio_find_device_in_devset); + /* * Device objects - create, release, get, put, search */ @@ -258,7 +273,8 @@ static int __vfio_register_dev(struct vfio_device *device, if (WARN_ON(IS_ENABLED(CONFIG_IOMMUFD) && (!device->ops->bind_iommufd || !device->ops->unbind_iommufd || - !device->ops->attach_ioas))) + !device->ops->attach_ioas || + !device->ops->detach_ioas))) return -EINVAL; /* @@ -276,7 +292,18 @@ static int __vfio_register_dev(struct vfio_device *device, if (ret) return ret; - ret = device_add(&device->device); + /* + * VFIO always sets IOMMU_CACHE because we offer no way for userspace to + * restore cache coherency. It has to be checked here because it is only + * valid for cases where we are using iommu groups. + */ + if (type == VFIO_IOMMU && !vfio_device_is_noiommu(device) && + !device_iommu_capable(device->dev, IOMMU_CAP_CACHE_COHERENCY)) { + ret = -EINVAL; + goto err_out; + } + + ret = vfio_device_add(device); if (ret) goto err_out; @@ -316,6 +343,18 @@ void vfio_unregister_group_dev(struct vfio_device *device) bool interrupted = false; long rc; + /* + * Prevent new device opened by userspace via the + * VFIO_GROUP_GET_DEVICE_FD in the group path. + */ + vfio_device_group_unregister(device); + + /* + * Balances vfio_device_add() in register path, also prevents + * new device opened by userspace in the cdev path. + */ + vfio_device_del(device); + vfio_device_put_registration(device); rc = try_wait_for_completion(&device->comp); while (rc <= 0) { @@ -339,18 +378,13 @@ void vfio_unregister_group_dev(struct vfio_device *device) } } - vfio_device_group_unregister(device); - - /* Balances device_add in register path */ - device_del(&device->device); - /* Balances vfio_device_set_group in register path */ vfio_device_remove_group(device); } EXPORT_SYMBOL_GPL(vfio_unregister_group_dev); #ifdef CONFIG_HAVE_KVM -void _vfio_device_get_kvm_safe(struct vfio_device *device, struct kvm *kvm) +void vfio_device_get_kvm_safe(struct vfio_device *device, struct kvm *kvm) { void (*pfn)(struct kvm *kvm); bool (*fn)(struct kvm *kvm); @@ -358,6 +392,9 @@ void _vfio_device_get_kvm_safe(struct vfio_device *device, struct kvm *kvm) lockdep_assert_held(&device->dev_set->lock); + if (!kvm) + return; + pfn = symbol_get(kvm_put_kvm); if (WARN_ON(!pfn)) return; @@ -404,9 +441,25 @@ static bool vfio_assert_device_open(struct vfio_device *device) return !WARN_ON_ONCE(!READ_ONCE(device->open_count)); } -static int vfio_device_first_open(struct vfio_device *device, - struct iommufd_ctx *iommufd) +struct vfio_device_file * +vfio_allocate_device_file(struct vfio_device *device) { + struct vfio_device_file *df; + + df = kzalloc(sizeof(*df), GFP_KERNEL_ACCOUNT); + if (!df) + return ERR_PTR(-ENOMEM); + + df->device = device; + spin_lock_init(&df->kvm_ref_lock); + + return df; +} + +static int vfio_df_device_first_open(struct vfio_device_file *df) +{ + struct vfio_device *device = df->device; + struct iommufd_ctx *iommufd = df->iommufd; int ret; lockdep_assert_held(&device->dev_set->lock); @@ -415,7 +468,7 @@ static int vfio_device_first_open(struct vfio_device *device, return -ENODEV; if (iommufd) - ret = vfio_iommufd_bind(device, iommufd); + ret = vfio_df_iommufd_bind(df); else ret = vfio_device_group_use_iommu(device); if (ret) @@ -430,7 +483,7 @@ static int vfio_device_first_open(struct vfio_device *device, err_unuse_iommu: if (iommufd) - vfio_iommufd_unbind(device); + vfio_df_iommufd_unbind(df); else vfio_device_group_unuse_iommu(device); err_module_put: @@ -438,29 +491,39 @@ err_module_put: return ret; } -static void vfio_device_last_close(struct vfio_device *device, - struct iommufd_ctx *iommufd) +static void vfio_df_device_last_close(struct vfio_device_file *df) { + struct vfio_device *device = df->device; + struct iommufd_ctx *iommufd = df->iommufd; + lockdep_assert_held(&device->dev_set->lock); if (device->ops->close_device) device->ops->close_device(device); if (iommufd) - vfio_iommufd_unbind(device); + vfio_df_iommufd_unbind(df); else vfio_device_group_unuse_iommu(device); module_put(device->dev->driver->owner); } -int vfio_device_open(struct vfio_device *device, struct iommufd_ctx *iommufd) +int vfio_df_open(struct vfio_device_file *df) { + struct vfio_device *device = df->device; int ret = 0; lockdep_assert_held(&device->dev_set->lock); + /* + * Only the group path allows the device to be opened multiple + * times. The device cdev path doesn't have a secure way for it. + */ + if (device->open_count != 0 && !df->group) + return -EINVAL; + device->open_count++; if (device->open_count == 1) { - ret = vfio_device_first_open(device, iommufd); + ret = vfio_df_device_first_open(df); if (ret) device->open_count--; } @@ -468,14 +531,15 @@ int vfio_device_open(struct vfio_device *device, struct iommufd_ctx *iommufd) return ret; } -void vfio_device_close(struct vfio_device *device, - struct iommufd_ctx *iommufd) +void vfio_df_close(struct vfio_device_file *df) { + struct vfio_device *device = df->device; + lockdep_assert_held(&device->dev_set->lock); vfio_assert_device_open(device); if (device->open_count == 1) - vfio_device_last_close(device, iommufd); + vfio_df_device_last_close(df); device->open_count--; } @@ -517,12 +581,18 @@ static inline void vfio_device_pm_runtime_put(struct vfio_device *device) */ static int vfio_device_fops_release(struct inode *inode, struct file *filep) { - struct vfio_device *device = filep->private_data; + struct vfio_device_file *df = filep->private_data; + struct vfio_device *device = df->device; - vfio_device_group_close(device); + if (df->group) + vfio_df_group_close(df); + else + vfio_df_unbind_iommufd(df); vfio_device_put_registration(device); + kfree(df); + return 0; } @@ -1087,16 +1157,38 @@ static int vfio_ioctl_device_feature(struct vfio_device *device, static long vfio_device_fops_unl_ioctl(struct file *filep, unsigned int cmd, unsigned long arg) { - struct vfio_device *device = filep->private_data; + struct vfio_device_file *df = filep->private_data; + struct vfio_device *device = df->device; + void __user *uptr = (void __user *)arg; int ret; + if (cmd == VFIO_DEVICE_BIND_IOMMUFD) + return vfio_df_ioctl_bind_iommufd(df, uptr); + + /* Paired with smp_store_release() following vfio_df_open() */ + if (!smp_load_acquire(&df->access_granted)) + return -EINVAL; + ret = vfio_device_pm_runtime_get(device); if (ret) return ret; + /* cdev only ioctls */ + if (IS_ENABLED(CONFIG_VFIO_DEVICE_CDEV) && !df->group) { + switch (cmd) { + case VFIO_DEVICE_ATTACH_IOMMUFD_PT: + ret = vfio_df_ioctl_attach_pt(df, uptr); + goto out; + + case VFIO_DEVICE_DETACH_IOMMUFD_PT: + ret = vfio_df_ioctl_detach_pt(df, uptr); + goto out; + } + } + switch (cmd) { case VFIO_DEVICE_FEATURE: - ret = vfio_ioctl_device_feature(device, (void __user *)arg); + ret = vfio_ioctl_device_feature(device, uptr); break; default: @@ -1106,7 +1198,7 @@ static long vfio_device_fops_unl_ioctl(struct file *filep, ret = device->ops->ioctl(device, cmd, arg); break; } - +out: vfio_device_pm_runtime_put(device); return ret; } @@ -1114,7 +1206,12 @@ static long vfio_device_fops_unl_ioctl(struct file *filep, static ssize_t vfio_device_fops_read(struct file *filep, char __user *buf, size_t count, loff_t *ppos) { - struct vfio_device *device = filep->private_data; + struct vfio_device_file *df = filep->private_data; + struct vfio_device *device = df->device; + + /* Paired with smp_store_release() following vfio_df_open() */ + if (!smp_load_acquire(&df->access_granted)) + return -EINVAL; if (unlikely(!device->ops->read)) return -EINVAL; @@ -1126,7 +1223,12 @@ static ssize_t vfio_device_fops_write(struct file *filep, const char __user *buf, size_t count, loff_t *ppos) { - struct vfio_device *device = filep->private_data; + struct vfio_device_file *df = filep->private_data; + struct vfio_device *device = df->device; + + /* Paired with smp_store_release() following vfio_df_open() */ + if (!smp_load_acquire(&df->access_granted)) + return -EINVAL; if (unlikely(!device->ops->write)) return -EINVAL; @@ -1136,7 +1238,12 @@ static ssize_t vfio_device_fops_write(struct file *filep, static int vfio_device_fops_mmap(struct file *filep, struct vm_area_struct *vma) { - struct vfio_device *device = filep->private_data; + struct vfio_device_file *df = filep->private_data; + struct vfio_device *device = df->device; + + /* Paired with smp_store_release() following vfio_df_open() */ + if (!smp_load_acquire(&df->access_granted)) + return -EINVAL; if (unlikely(!device->ops->mmap)) return -EINVAL; @@ -1146,6 +1253,7 @@ static int vfio_device_fops_mmap(struct file *filep, struct vm_area_struct *vma) const struct file_operations vfio_device_fops = { .owner = THIS_MODULE, + .open = vfio_device_fops_cdev_open, .release = vfio_device_fops_release, .read = vfio_device_fops_read, .write = vfio_device_fops_write, @@ -1154,6 +1262,88 @@ const struct file_operations vfio_device_fops = { .mmap = vfio_device_fops_mmap, }; +static struct vfio_device *vfio_device_from_file(struct file *file) +{ + struct vfio_device_file *df = file->private_data; + + if (file->f_op != &vfio_device_fops) + return NULL; + return df->device; +} + +/** + * vfio_file_is_valid - True if the file is valid vfio file + * @file: VFIO group file or VFIO device file + */ +bool vfio_file_is_valid(struct file *file) +{ + return vfio_group_from_file(file) || + vfio_device_from_file(file); +} +EXPORT_SYMBOL_GPL(vfio_file_is_valid); + +/** + * vfio_file_enforced_coherent - True if the DMA associated with the VFIO file + * is always CPU cache coherent + * @file: VFIO group file or VFIO device file + * + * Enforced coherency means that the IOMMU ignores things like the PCIe no-snoop + * bit in DMA transactions. A return of false indicates that the user has + * rights to access additional instructions such as wbinvd on x86. + */ +bool vfio_file_enforced_coherent(struct file *file) +{ + struct vfio_device *device; + struct vfio_group *group; + + group = vfio_group_from_file(file); + if (group) + return vfio_group_enforced_coherent(group); + + device = vfio_device_from_file(file); + if (device) + return device_iommu_capable(device->dev, + IOMMU_CAP_ENFORCE_CACHE_COHERENCY); + + return true; +} +EXPORT_SYMBOL_GPL(vfio_file_enforced_coherent); + +static void vfio_device_file_set_kvm(struct file *file, struct kvm *kvm) +{ + struct vfio_device_file *df = file->private_data; + + /* + * The kvm is first recorded in the vfio_device_file, and will + * be propagated to vfio_device::kvm when the file is bound to + * iommufd successfully in the vfio device cdev path. + */ + spin_lock(&df->kvm_ref_lock); + df->kvm = kvm; + spin_unlock(&df->kvm_ref_lock); +} + +/** + * vfio_file_set_kvm - Link a kvm with VFIO drivers + * @file: VFIO group file or VFIO device file + * @kvm: KVM to link + * + * When a VFIO device is first opened the KVM will be available in + * device->kvm if one was associated with the file. + */ +void vfio_file_set_kvm(struct file *file, struct kvm *kvm) +{ + struct vfio_group *group; + + group = vfio_group_from_file(file); + if (group) + vfio_group_set_kvm(group, kvm); + + if (vfio_device_from_file(file)) + vfio_device_file_set_kvm(file, kvm); +} +EXPORT_SYMBOL_GPL(vfio_file_set_kvm); + /* * Sub-module support */ @@ -1293,6 +1483,8 @@ int vfio_pin_pages(struct vfio_device *device, dma_addr_t iova, /* group->container cannot change while a vfio device is open */ if (!pages || !npage || WARN_ON(!vfio_assert_device_open(device))) return -EINVAL; + if (!device->ops->dma_unmap) + return -EINVAL; if (vfio_device_has_container(device)) return vfio_device_container_pin_pages(device, iova, npage, prot, pages); @@ -1330,6 +1522,8 @@ void vfio_unpin_pages(struct vfio_device *device, dma_addr_t iova, int npage) { if (WARN_ON(!vfio_assert_device_open(device))) return; + if (WARN_ON(!device->ops->dma_unmap)) + return; if (vfio_device_has_container(device)) { vfio_device_container_unpin_pages(device, iova, npage); @@ -1415,9 +1609,16 @@ static int __init vfio_init(void) goto err_dev_class; } + ret = vfio_cdev_init(vfio.device_class); + if (ret) + goto err_alloc_dev_chrdev; + pr_info(DRIVER_DESC " version: " DRIVER_VERSION "\n"); return 0; +err_alloc_dev_chrdev: + class_destroy(vfio.device_class); + vfio.device_class = NULL; err_dev_class: vfio_virqfd_exit(); err_virqfd: @@ -1428,6 +1629,7 @@ err_virqfd: static void __exit vfio_cleanup(void) { ida_destroy(&vfio.device_ida); + vfio_cdev_cleanup(); class_destroy(vfio.device_class); vfio.device_class = NULL; vfio_virqfd_exit(); |