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-rw-r--r--arch/um/drivers/virtio_uml.c92
-rw-r--r--arch/um/include/linux/time-internal.h6
-rw-r--r--arch/um/include/shared/irq_kern.h60
-rw-r--r--arch/um/kernel/irq.c171
-rw-r--r--arch/um/kernel/time.c7
5 files changed, 267 insertions, 69 deletions
diff --git a/arch/um/drivers/virtio_uml.c b/arch/um/drivers/virtio_uml.c
index 9db9d00b2dc2..bda3ab468938 100644
--- a/arch/um/drivers/virtio_uml.c
+++ b/arch/um/drivers/virtio_uml.c
@@ -55,16 +55,14 @@ struct virtio_uml_device {
u64 protocol_features;
u8 status;
u8 registered:1;
+
+ u8 config_changed_irq:1;
+ uint64_t vq_irq_vq_map;
};
struct virtio_uml_vq_info {
int kick_fd, call_fd;
char name[32];
-#ifdef CONFIG_UML_TIME_TRAVEL_SUPPORT
- struct virtqueue *vq;
- vq_callback_t *callback;
- struct time_travel_event defer;
-#endif
bool suspended;
};
@@ -351,9 +349,9 @@ static void vhost_user_reply(struct virtio_uml_device *vu_dev,
rc, size);
}
-static irqreturn_t vu_req_interrupt(int irq, void *data)
+static irqreturn_t vu_req_read_message(struct virtio_uml_device *vu_dev,
+ struct time_travel_event *ev)
{
- struct virtio_uml_device *vu_dev = data;
struct virtqueue *vq;
int response = 1;
struct {
@@ -371,14 +369,14 @@ static irqreturn_t vu_req_interrupt(int irq, void *data)
switch (msg.msg.header.request) {
case VHOST_USER_SLAVE_CONFIG_CHANGE_MSG:
- virtio_config_changed(&vu_dev->vdev);
+ vu_dev->config_changed_irq = true;
response = 0;
break;
case VHOST_USER_SLAVE_VRING_CALL:
virtio_device_for_each_vq((&vu_dev->vdev), vq) {
if (vq->index == msg.msg.payload.vring_state.index) {
response = 0;
- vring_interrupt(0 /* ignored */, vq);
+ vu_dev->vq_irq_vq_map |= BIT_ULL(vq->index);
break;
}
}
@@ -392,12 +390,45 @@ static irqreturn_t vu_req_interrupt(int irq, void *data)
msg.msg.header.request);
}
+ if (ev)
+ time_travel_add_irq_event(ev);
+
if (msg.msg.header.flags & VHOST_USER_FLAG_NEED_REPLY)
vhost_user_reply(vu_dev, &msg.msg, response);
return IRQ_HANDLED;
}
+static irqreturn_t vu_req_interrupt(int irq, void *data)
+{
+ struct virtio_uml_device *vu_dev = data;
+ irqreturn_t ret = IRQ_HANDLED;
+
+ if (!um_irq_timetravel_handler_used())
+ ret = vu_req_read_message(vu_dev, NULL);
+
+ if (vu_dev->vq_irq_vq_map) {
+ struct virtqueue *vq;
+
+ virtio_device_for_each_vq((&vu_dev->vdev), vq) {
+ if (vu_dev->vq_irq_vq_map & BIT_ULL(vq->index))
+ vring_interrupt(0 /* ignored */, vq);
+ }
+ vu_dev->vq_irq_vq_map = 0;
+ } else if (vu_dev->config_changed_irq) {
+ virtio_config_changed(&vu_dev->vdev);
+ vu_dev->config_changed_irq = false;
+ }
+
+ return ret;
+}
+
+static void vu_req_interrupt_comm_handler(int irq, int fd, void *data,
+ struct time_travel_event *ev)
+{
+ vu_req_read_message(data, ev);
+}
+
static int vhost_user_init_slave_req(struct virtio_uml_device *vu_dev)
{
int rc, req_fds[2];
@@ -408,9 +439,10 @@ static int vhost_user_init_slave_req(struct virtio_uml_device *vu_dev)
return rc;
vu_dev->req_fd = req_fds[0];
- rc = um_request_irq(UM_IRQ_ALLOC, vu_dev->req_fd, IRQ_READ,
- vu_req_interrupt, IRQF_SHARED,
- vu_dev->pdev->name, vu_dev);
+ rc = um_request_irq_tt(UM_IRQ_ALLOC, vu_dev->req_fd, IRQ_READ,
+ vu_req_interrupt, IRQF_SHARED,
+ vu_dev->pdev->name, vu_dev,
+ vu_req_interrupt_comm_handler);
if (rc < 0)
goto err_close;
@@ -882,23 +914,6 @@ out:
return rc;
}
-#ifdef CONFIG_UML_TIME_TRAVEL_SUPPORT
-static void vu_defer_irq_handle(struct time_travel_event *d)
-{
- struct virtio_uml_vq_info *info;
-
- info = container_of(d, struct virtio_uml_vq_info, defer);
- info->callback(info->vq);
-}
-
-static void vu_defer_irq_callback(struct virtqueue *vq)
-{
- struct virtio_uml_vq_info *info = vq->priv;
-
- time_travel_add_irq_event(&info->defer);
-}
-#endif
-
static struct virtqueue *vu_setup_vq(struct virtio_device *vdev,
unsigned index, vq_callback_t *callback,
const char *name, bool ctx)
@@ -918,18 +933,6 @@ static struct virtqueue *vu_setup_vq(struct virtio_device *vdev,
snprintf(info->name, sizeof(info->name), "%s.%d-%s", pdev->name,
pdev->id, name);
-#ifdef CONFIG_UML_TIME_TRAVEL_SUPPORT
- /*
- * When we get an interrupt, we must bounce it through the simulation
- * calendar (the time-travel=ext:... socket).
- */
- if (time_travel_mode == TT_MODE_EXTERNAL && callback) {
- info->callback = callback;
- callback = vu_defer_irq_callback;
- time_travel_set_event_fn(&info->defer, vu_defer_irq_handle);
- }
-#endif
-
vq = vring_create_virtqueue(index, num, PAGE_SIZE, vdev, true, true,
ctx, vu_notify, callback, info->name);
if (!vq) {
@@ -938,9 +941,6 @@ static struct virtqueue *vu_setup_vq(struct virtio_device *vdev,
}
vq->priv = info;
num = virtqueue_get_vring_size(vq);
-#ifdef CONFIG_UML_TIME_TRAVEL_SUPPORT
- info->vq = vq;
-#endif
if (vu_dev->protocol_features &
BIT_ULL(VHOST_USER_PROTOCOL_F_INBAND_NOTIFICATIONS)) {
@@ -999,6 +999,10 @@ static int vu_find_vqs(struct virtio_device *vdev, unsigned nvqs,
int i, queue_idx = 0, rc;
struct virtqueue *vq;
+ /* not supported for now */
+ if (WARN_ON(nvqs > 64))
+ return -EINVAL;
+
rc = vhost_user_set_mem_table(vu_dev);
if (rc)
return rc;
diff --git a/arch/um/include/linux/time-internal.h b/arch/um/include/linux/time-internal.h
index 68e45e950137..8688e16e832b 100644
--- a/arch/um/include/linux/time-internal.h
+++ b/arch/um/include/linux/time-internal.h
@@ -7,6 +7,7 @@
#ifndef __TIMER_INTERNAL_H__
#define __TIMER_INTERNAL_H__
#include <linux/list.h>
+#include <asm/bug.h>
#define TIMER_MULTIPLIER 256
#define TIMER_MIN_DELTA 500
@@ -74,6 +75,11 @@ static inline void time_travel_propagate_time(void)
static inline void time_travel_wait_readable(int fd)
{
}
+
+static inline void time_travel_add_irq_event(struct time_travel_event *e)
+{
+ WARN_ON(1);
+}
#endif /* CONFIG_UML_TIME_TRAVEL_SUPPORT */
/*
diff --git a/arch/um/include/shared/irq_kern.h b/arch/um/include/shared/irq_kern.h
index 7807de593bda..f2dc817abb7c 100644
--- a/arch/um/include/shared/irq_kern.h
+++ b/arch/um/include/shared/irq_kern.h
@@ -7,6 +7,7 @@
#define __IRQ_KERN_H__
#include <linux/interrupt.h>
+#include <linux/time-internal.h>
#include <asm/ptrace.h>
#include "irq_user.h"
@@ -15,5 +16,64 @@
int um_request_irq(int irq, int fd, enum um_irq_type type,
irq_handler_t handler, unsigned long irqflags,
const char *devname, void *dev_id);
+
+#ifdef CONFIG_UML_TIME_TRAVEL_SUPPORT
+/**
+ * um_request_irq_tt - request an IRQ with timetravel handler
+ *
+ * @irq: the IRQ number, or %UM_IRQ_ALLOC
+ * @fd: The file descriptor to request an IRQ for
+ * @type: read or write
+ * @handler: the (generic style) IRQ handler
+ * @irqflags: Linux IRQ flags
+ * @devname: name for this to show
+ * @dev_id: data pointer to pass to the IRQ handler
+ * @timetravel_handler: the timetravel interrupt handler, invoked with the IRQ
+ * number, fd, dev_id and time-travel event pointer.
+ *
+ * Returns: The interrupt number assigned or a negative error.
+ *
+ * Note that the timetravel handler is invoked only if the time_travel_mode is
+ * %TT_MODE_EXTERNAL, and then it is invoked even while the system is suspended!
+ * This function must call time_travel_add_irq_event() for the event passed with
+ * an appropriate delay, before sending an ACK on the socket it was invoked for.
+ *
+ * If this was called while the system is suspended, then adding the event will
+ * cause the system to resume.
+ *
+ * Since this function will almost certainly have to handle the FD's condition,
+ * a read will consume the message, and after that it is up to the code using
+ * it to pass such a message to the @handler in whichever way it can.
+ *
+ * If time_travel_mode is not %TT_MODE_EXTERNAL the @timetravel_handler will
+ * not be invoked at all and the @handler must handle the FD becoming
+ * readable (or writable) instead. Use um_irq_timetravel_handler_used() to
+ * distinguish these cases.
+ *
+ * See virtio_uml.c for an example.
+ */
+int um_request_irq_tt(int irq, int fd, enum um_irq_type type,
+ irq_handler_t handler, unsigned long irqflags,
+ const char *devname, void *dev_id,
+ void (*timetravel_handler)(int, int, void *,
+ struct time_travel_event *));
+#else
+static inline
+int um_request_irq_tt(int irq, int fd, enum um_irq_type type,
+ irq_handler_t handler, unsigned long irqflags,
+ const char *devname, void *dev_id,
+ void (*timetravel_handler)(int, int, void *,
+ struct time_travel_event *))
+{
+ return um_request_irq(irq, fd, type, handler, irqflags,
+ devname, dev_id);
+}
+#endif
+
+static inline bool um_irq_timetravel_handler_used(void)
+{
+ return time_travel_mode == TT_MODE_EXTERNAL;
+}
+
void um_free_irq(int irq, void *dev_id);
#endif
diff --git a/arch/um/kernel/irq.c b/arch/um/kernel/irq.c
index 3741d2380060..82af5191e73d 100644
--- a/arch/um/kernel/irq.c
+++ b/arch/um/kernel/irq.c
@@ -20,7 +20,7 @@
#include <os.h>
#include <irq_user.h>
#include <irq_kern.h>
-#include <as-layout.h>
+#include <linux/time-internal.h>
extern void free_irqs(void);
@@ -38,6 +38,12 @@ struct irq_reg {
bool active;
bool pending;
bool wakeup;
+#ifdef CONFIG_UML_TIME_TRAVEL_SUPPORT
+ bool pending_on_resume;
+ void (*timetravel_handler)(int, int, void *,
+ struct time_travel_event *);
+ struct time_travel_event event;
+#endif
};
struct irq_entry {
@@ -51,6 +57,7 @@ struct irq_entry {
static DEFINE_SPINLOCK(irq_lock);
static LIST_HEAD(active_fds);
static DECLARE_BITMAP(irqs_allocated, NR_IRQS);
+static bool irqs_suspended;
static void irq_io_loop(struct irq_reg *irq, struct uml_pt_regs *regs)
{
@@ -74,9 +81,65 @@ static void irq_io_loop(struct irq_reg *irq, struct uml_pt_regs *regs)
}
}
-void sigio_handler_suspend(int sig, struct siginfo *unused_si, struct uml_pt_regs *regs)
+#ifdef CONFIG_UML_TIME_TRAVEL_SUPPORT
+static void irq_event_handler(struct time_travel_event *ev)
{
- /* nothing */
+ struct irq_reg *reg = container_of(ev, struct irq_reg, event);
+
+ /* do nothing if suspended - just to cause a wakeup */
+ if (irqs_suspended)
+ return;
+
+ generic_handle_irq(reg->irq);
+}
+
+static bool irq_do_timetravel_handler(struct irq_entry *entry,
+ enum um_irq_type t)
+{
+ struct irq_reg *reg = &entry->reg[t];
+
+ if (!reg->timetravel_handler)
+ return false;
+
+ /* prevent nesting - we'll get it again later when we SIGIO ourselves */
+ if (reg->pending_on_resume)
+ return true;
+
+ reg->timetravel_handler(reg->irq, entry->fd, reg->id, &reg->event);
+
+ if (!reg->event.pending)
+ return false;
+
+ if (irqs_suspended)
+ reg->pending_on_resume = true;
+ return true;
+}
+#else
+static bool irq_do_timetravel_handler(struct irq_entry *entry,
+ enum um_irq_type t)
+{
+ return false;
+}
+#endif
+
+static void sigio_reg_handler(int idx, struct irq_entry *entry, enum um_irq_type t,
+ struct uml_pt_regs *regs)
+{
+ struct irq_reg *reg = &entry->reg[t];
+
+ if (!reg->events)
+ return;
+
+ if (os_epoll_triggered(idx, reg->events) <= 0)
+ return;
+
+ if (irq_do_timetravel_handler(entry, t))
+ return;
+
+ if (irqs_suspended)
+ return;
+
+ irq_io_loop(reg, regs);
}
void sigio_handler(int sig, struct siginfo *unused_si, struct uml_pt_regs *regs)
@@ -84,6 +147,9 @@ void sigio_handler(int sig, struct siginfo *unused_si, struct uml_pt_regs *regs)
struct irq_entry *irq_entry;
int n, i;
+ if (irqs_suspended && !um_irq_timetravel_handler_used())
+ return;
+
while (1) {
/* This is now lockless - epoll keeps back-referencesto the irqs
* which have trigger it so there is no need to walk the irq
@@ -105,19 +171,13 @@ void sigio_handler(int sig, struct siginfo *unused_si, struct uml_pt_regs *regs)
irq_entry = os_epoll_get_data_pointer(i);
- for (t = 0; t < NUM_IRQ_TYPES; t++) {
- int events = irq_entry->reg[t].events;
-
- if (!events)
- continue;
-
- if (os_epoll_triggered(i, events) > 0)
- irq_io_loop(&irq_entry->reg[t], regs);
- }
+ for (t = 0; t < NUM_IRQ_TYPES; t++)
+ sigio_reg_handler(i, irq_entry, t, regs);
}
}
- free_irqs();
+ if (!irqs_suspended)
+ free_irqs();
}
static struct irq_entry *get_irq_entry_by_fd(int fd)
@@ -169,7 +229,9 @@ static void update_or_free_irq_entry(struct irq_entry *entry)
free_irq_entry(entry, false);
}
-static int activate_fd(int irq, int fd, enum um_irq_type type, void *dev_id)
+static int activate_fd(int irq, int fd, enum um_irq_type type, void *dev_id,
+ void (*timetravel_handler)(int, int, void *,
+ struct time_travel_event *))
{
struct irq_entry *irq_entry;
int err, events = os_event_mask(type);
@@ -206,6 +268,13 @@ static int activate_fd(int irq, int fd, enum um_irq_type type, void *dev_id)
irq_entry->reg[type].active = true;
irq_entry->reg[type].events = events;
+#ifdef CONFIG_UML_TIME_TRAVEL_SUPPORT
+ if (um_irq_timetravel_handler_used()) {
+ irq_entry->reg[type].timetravel_handler = timetravel_handler;
+ irq_entry->reg[type].event.fn = irq_event_handler;
+ }
+#endif
+
WARN_ON(!update_irq_entry(irq_entry));
spin_unlock_irqrestore(&irq_lock, flags);
@@ -339,9 +408,12 @@ void um_free_irq(int irq, void *dev)
}
EXPORT_SYMBOL(um_free_irq);
-int um_request_irq(int irq, int fd, enum um_irq_type type,
- irq_handler_t handler, unsigned long irqflags,
- const char *devname, void *dev_id)
+static int
+_um_request_irq(int irq, int fd, enum um_irq_type type,
+ irq_handler_t handler, unsigned long irqflags,
+ const char *devname, void *dev_id,
+ void (*timetravel_handler)(int, int, void *,
+ struct time_travel_event *))
{
int err;
@@ -360,7 +432,7 @@ int um_request_irq(int irq, int fd, enum um_irq_type type,
return -ENOSPC;
if (fd != -1) {
- err = activate_fd(irq, fd, type, dev_id);
+ err = activate_fd(irq, fd, type, dev_id, timetravel_handler);
if (err)
goto error;
}
@@ -374,20 +446,41 @@ error:
clear_bit(irq, irqs_allocated);
return err;
}
+
+int um_request_irq(int irq, int fd, enum um_irq_type type,
+ irq_handler_t handler, unsigned long irqflags,
+ const char *devname, void *dev_id)
+{
+ return _um_request_irq(irq, fd, type, handler, irqflags,
+ devname, dev_id, NULL);
+}
EXPORT_SYMBOL(um_request_irq);
+#ifdef CONFIG_UML_TIME_TRAVEL_SUPPORT
+int um_request_irq_tt(int irq, int fd, enum um_irq_type type,
+ irq_handler_t handler, unsigned long irqflags,
+ const char *devname, void *dev_id,
+ void (*timetravel_handler)(int, int, void *,
+ struct time_travel_event *))
+{
+ return _um_request_irq(irq, fd, type, handler, irqflags,
+ devname, dev_id, timetravel_handler);
+}
+EXPORT_SYMBOL(um_request_irq_tt);
+#endif
+
#ifdef CONFIG_PM_SLEEP
void um_irqs_suspend(void)
{
struct irq_entry *entry;
unsigned long flags;
- sig_info[SIGIO] = sigio_handler_suspend;
+ irqs_suspended = true;
spin_lock_irqsave(&irq_lock, flags);
list_for_each_entry(entry, &active_fds, list) {
enum um_irq_type t;
- bool wake = false;
+ bool clear = true;
for (t = 0; t < NUM_IRQ_TYPES; t++) {
if (!entry->reg[t].events)
@@ -400,13 +493,17 @@ void um_irqs_suspend(void)
* any FDs that should be suspended.
*/
if (entry->reg[t].wakeup ||
- entry->reg[t].irq == SIGIO_WRITE_IRQ) {
- wake = true;
+ entry->reg[t].irq == SIGIO_WRITE_IRQ
+#ifdef CONFIG_UML_TIME_TRAVEL_SUPPORT
+ || entry->reg[t].timetravel_handler
+#endif
+ ) {
+ clear = false;
break;
}
}
- if (!wake) {
+ if (clear) {
entry->suspended = true;
os_clear_fd_async(entry->fd);
entry->sigio_workaround =
@@ -421,7 +518,31 @@ void um_irqs_resume(void)
struct irq_entry *entry;
unsigned long flags;
- spin_lock_irqsave(&irq_lock, flags);
+
+ local_irq_save(flags);
+#ifdef CONFIG_UML_TIME_TRAVEL_SUPPORT
+ /*
+ * We don't need to lock anything here since we're in resume
+ * and nothing else is running, but have disabled IRQs so we
+ * don't try anything else with the interrupt list from there.
+ */
+ list_for_each_entry(entry, &active_fds, list) {
+ enum um_irq_type t;
+
+ for (t = 0; t < NUM_IRQ_TYPES; t++) {
+ struct irq_reg *reg = &entry->reg[t];
+
+ if (reg->pending_on_resume) {
+ irq_enter();
+ generic_handle_irq(reg->irq);
+ irq_exit();
+ reg->pending_on_resume = false;
+ }
+ }
+ }
+#endif
+
+ spin_lock(&irq_lock);
list_for_each_entry(entry, &active_fds, list) {
if (entry->suspended) {
int err = os_set_fd_async(entry->fd);
@@ -437,7 +558,7 @@ void um_irqs_resume(void)
}
spin_unlock_irqrestore(&irq_lock, flags);
- sig_info[SIGIO] = sigio_handler;
+ irqs_suspended = false;
send_sigio_to_self();
}
diff --git a/arch/um/kernel/time.c b/arch/um/kernel/time.c
index 315248b03941..8144406b6ea3 100644
--- a/arch/um/kernel/time.c
+++ b/arch/um/kernel/time.c
@@ -278,6 +278,7 @@ static void __time_travel_add_event(struct time_travel_event *e,
{
struct time_travel_event *tmp;
bool inserted = false;
+ unsigned long flags;
if (e->pending)
return;
@@ -285,6 +286,7 @@ static void __time_travel_add_event(struct time_travel_event *e,
e->pending = true;
e->time = time;
+ local_irq_save(flags);
list_for_each_entry(tmp, &time_travel_events, list) {
/*
* Add the new entry before one with higher time,
@@ -307,6 +309,7 @@ static void __time_travel_add_event(struct time_travel_event *e,
tmp = time_travel_first_event();
time_travel_ext_update_request(tmp->time);
time_travel_next_event = tmp->time;
+ local_irq_restore(flags);
}
static void time_travel_add_event(struct time_travel_event *e,
@@ -383,10 +386,14 @@ static void time_travel_deliver_event(struct time_travel_event *e)
static bool time_travel_del_event(struct time_travel_event *e)
{
+ unsigned long flags;
+
if (!e->pending)
return false;
+ local_irq_save(flags);
list_del(&e->list);
e->pending = false;
+ local_irq_restore(flags);
return true;
}
generated by cgit (git 2.34.1) at 2024-06-10 09:03:37 +0000