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Diffstat (limited to 'drivers/vhost/vhost.c')
-rw-r--r--drivers/vhost/vhost.c97
1 files changed, 50 insertions, 47 deletions
diff --git a/drivers/vhost/vhost.c b/drivers/vhost/vhost.c
index 78987e481bc6..c90f4374442a 100644
--- a/drivers/vhost/vhost.c
+++ b/drivers/vhost/vhost.c
@@ -18,7 +18,6 @@
#include <linux/mmu_context.h>
#include <linux/miscdevice.h>
#include <linux/mutex.h>
-#include <linux/rcupdate.h>
#include <linux/poll.h>
#include <linux/file.h>
#include <linux/highmem.h>
@@ -191,6 +190,7 @@ static void vhost_vq_reset(struct vhost_dev *dev,
vq->log_used = false;
vq->log_addr = -1ull;
vq->private_data = NULL;
+ vq->acked_features = 0;
vq->log_base = NULL;
vq->error_ctx = NULL;
vq->error = NULL;
@@ -198,6 +198,7 @@ static void vhost_vq_reset(struct vhost_dev *dev,
vq->call_ctx = NULL;
vq->call = NULL;
vq->log_ctx = NULL;
+ vq->memory = NULL;
}
static int vhost_worker(void *data)
@@ -415,11 +416,18 @@ EXPORT_SYMBOL_GPL(vhost_dev_reset_owner_prepare);
/* Caller should have device mutex */
void vhost_dev_reset_owner(struct vhost_dev *dev, struct vhost_memory *memory)
{
+ int i;
+
vhost_dev_cleanup(dev, true);
/* Restore memory to default empty mapping. */
memory->nregions = 0;
- RCU_INIT_POINTER(dev->memory, memory);
+ dev->memory = memory;
+ /* We don't need VQ locks below since vhost_dev_cleanup makes sure
+ * VQs aren't running.
+ */
+ for (i = 0; i < dev->nvqs; ++i)
+ dev->vqs[i]->memory = memory;
}
EXPORT_SYMBOL_GPL(vhost_dev_reset_owner);
@@ -462,10 +470,8 @@ void vhost_dev_cleanup(struct vhost_dev *dev, bool locked)
fput(dev->log_file);
dev->log_file = NULL;
/* No one will access memory at this point */
- kfree(rcu_dereference_protected(dev->memory,
- locked ==
- lockdep_is_held(&dev->mutex)));
- RCU_INIT_POINTER(dev->memory, NULL);
+ kfree(dev->memory);
+ dev->memory = NULL;
WARN_ON(!list_empty(&dev->work_list));
if (dev->worker) {
kthread_stop(dev->worker);
@@ -524,11 +530,13 @@ static int memory_access_ok(struct vhost_dev *d, struct vhost_memory *mem,
for (i = 0; i < d->nvqs; ++i) {
int ok;
+ bool log;
+
mutex_lock(&d->vqs[i]->mutex);
+ log = log_all || vhost_has_feature(d->vqs[i], VHOST_F_LOG_ALL);
/* If ring is inactive, will check when it's enabled. */
if (d->vqs[i]->private_data)
- ok = vq_memory_access_ok(d->vqs[i]->log_base, mem,
- log_all);
+ ok = vq_memory_access_ok(d->vqs[i]->log_base, mem, log);
else
ok = 1;
mutex_unlock(&d->vqs[i]->mutex);
@@ -538,12 +546,12 @@ static int memory_access_ok(struct vhost_dev *d, struct vhost_memory *mem,
return 1;
}
-static int vq_access_ok(struct vhost_dev *d, unsigned int num,
+static int vq_access_ok(struct vhost_virtqueue *vq, unsigned int num,
struct vring_desc __user *desc,
struct vring_avail __user *avail,
struct vring_used __user *used)
{
- size_t s = vhost_has_feature(d, VIRTIO_RING_F_EVENT_IDX) ? 2 : 0;
+ size_t s = vhost_has_feature(vq, VIRTIO_RING_F_EVENT_IDX) ? 2 : 0;
return access_ok(VERIFY_READ, desc, num * sizeof *desc) &&
access_ok(VERIFY_READ, avail,
sizeof *avail + num * sizeof *avail->ring + s) &&
@@ -555,26 +563,19 @@ static int vq_access_ok(struct vhost_dev *d, unsigned int num,
/* Caller should have device mutex but not vq mutex */
int vhost_log_access_ok(struct vhost_dev *dev)
{
- struct vhost_memory *mp;
-
- mp = rcu_dereference_protected(dev->memory,
- lockdep_is_held(&dev->mutex));
- return memory_access_ok(dev, mp, 1);
+ return memory_access_ok(dev, dev->memory, 1);
}
EXPORT_SYMBOL_GPL(vhost_log_access_ok);
/* Verify access for write logging. */
/* Caller should have vq mutex and device mutex */
-static int vq_log_access_ok(struct vhost_dev *d, struct vhost_virtqueue *vq,
+static int vq_log_access_ok(struct vhost_virtqueue *vq,
void __user *log_base)
{
- struct vhost_memory *mp;
- size_t s = vhost_has_feature(d, VIRTIO_RING_F_EVENT_IDX) ? 2 : 0;
+ size_t s = vhost_has_feature(vq, VIRTIO_RING_F_EVENT_IDX) ? 2 : 0;
- mp = rcu_dereference_protected(vq->dev->memory,
- lockdep_is_held(&vq->mutex));
- return vq_memory_access_ok(log_base, mp,
- vhost_has_feature(vq->dev, VHOST_F_LOG_ALL)) &&
+ return vq_memory_access_ok(log_base, vq->memory,
+ vhost_has_feature(vq, VHOST_F_LOG_ALL)) &&
(!vq->log_used || log_access_ok(log_base, vq->log_addr,
sizeof *vq->used +
vq->num * sizeof *vq->used->ring + s));
@@ -584,8 +585,8 @@ static int vq_log_access_ok(struct vhost_dev *d, struct vhost_virtqueue *vq,
/* Caller should have vq mutex and device mutex */
int vhost_vq_access_ok(struct vhost_virtqueue *vq)
{
- return vq_access_ok(vq->dev, vq->num, vq->desc, vq->avail, vq->used) &&
- vq_log_access_ok(vq->dev, vq, vq->log_base);
+ return vq_access_ok(vq, vq->num, vq->desc, vq->avail, vq->used) &&
+ vq_log_access_ok(vq, vq->log_base);
}
EXPORT_SYMBOL_GPL(vhost_vq_access_ok);
@@ -593,6 +594,7 @@ static long vhost_set_memory(struct vhost_dev *d, struct vhost_memory __user *m)
{
struct vhost_memory mem, *newmem, *oldmem;
unsigned long size = offsetof(struct vhost_memory, regions);
+ int i;
if (copy_from_user(&mem, m, size))
return -EFAULT;
@@ -611,15 +613,19 @@ static long vhost_set_memory(struct vhost_dev *d, struct vhost_memory __user *m)
return -EFAULT;
}
- if (!memory_access_ok(d, newmem,
- vhost_has_feature(d, VHOST_F_LOG_ALL))) {
+ if (!memory_access_ok(d, newmem, 0)) {
kfree(newmem);
return -EFAULT;
}
- oldmem = rcu_dereference_protected(d->memory,
- lockdep_is_held(&d->mutex));
- rcu_assign_pointer(d->memory, newmem);
- synchronize_rcu();
+ oldmem = d->memory;
+ d->memory = newmem;
+
+ /* All memory accesses are done under some VQ mutex. */
+ for (i = 0; i < d->nvqs; ++i) {
+ mutex_lock(&d->vqs[i]->mutex);
+ d->vqs[i]->memory = newmem;
+ mutex_unlock(&d->vqs[i]->mutex);
+ }
kfree(oldmem);
return 0;
}
@@ -718,7 +724,7 @@ long vhost_vring_ioctl(struct vhost_dev *d, int ioctl, void __user *argp)
* If it is not, we don't as size might not have been setup.
* We will verify when backend is configured. */
if (vq->private_data) {
- if (!vq_access_ok(d, vq->num,
+ if (!vq_access_ok(vq, vq->num,
(void __user *)(unsigned long)a.desc_user_addr,
(void __user *)(unsigned long)a.avail_user_addr,
(void __user *)(unsigned long)a.used_user_addr)) {
@@ -858,7 +864,7 @@ long vhost_dev_ioctl(struct vhost_dev *d, unsigned int ioctl, void __user *argp)
vq = d->vqs[i];
mutex_lock(&vq->mutex);
/* If ring is inactive, will check when it's enabled. */
- if (vq->private_data && !vq_log_access_ok(d, vq, base))
+ if (vq->private_data && !vq_log_access_ok(vq, base))
r = -EFAULT;
else
vq->log_base = base;
@@ -1044,7 +1050,7 @@ int vhost_init_used(struct vhost_virtqueue *vq)
}
EXPORT_SYMBOL_GPL(vhost_init_used);
-static int translate_desc(struct vhost_dev *dev, u64 addr, u32 len,
+static int translate_desc(struct vhost_virtqueue *vq, u64 addr, u32 len,
struct iovec iov[], int iov_size)
{
const struct vhost_memory_region *reg;
@@ -1053,9 +1059,7 @@ static int translate_desc(struct vhost_dev *dev, u64 addr, u32 len,
u64 s = 0;
int ret = 0;
- rcu_read_lock();
-
- mem = rcu_dereference(dev->memory);
+ mem = vq->memory;
while ((u64)len > s) {
u64 size;
if (unlikely(ret >= iov_size)) {
@@ -1077,7 +1081,6 @@ static int translate_desc(struct vhost_dev *dev, u64 addr, u32 len,
++ret;
}
- rcu_read_unlock();
return ret;
}
@@ -1102,7 +1105,7 @@ static unsigned next_desc(struct vring_desc *desc)
return next;
}
-static int get_indirect(struct vhost_dev *dev, struct vhost_virtqueue *vq,
+static int get_indirect(struct vhost_virtqueue *vq,
struct iovec iov[], unsigned int iov_size,
unsigned int *out_num, unsigned int *in_num,
struct vhost_log *log, unsigned int *log_num,
@@ -1121,7 +1124,7 @@ static int get_indirect(struct vhost_dev *dev, struct vhost_virtqueue *vq,
return -EINVAL;
}
- ret = translate_desc(dev, indirect->addr, indirect->len, vq->indirect,
+ ret = translate_desc(vq, indirect->addr, indirect->len, vq->indirect,
UIO_MAXIOV);
if (unlikely(ret < 0)) {
vq_err(vq, "Translation failure %d in indirect.\n", ret);
@@ -1161,7 +1164,7 @@ static int get_indirect(struct vhost_dev *dev, struct vhost_virtqueue *vq,
return -EINVAL;
}
- ret = translate_desc(dev, desc.addr, desc.len, iov + iov_count,
+ ret = translate_desc(vq, desc.addr, desc.len, iov + iov_count,
iov_size - iov_count);
if (unlikely(ret < 0)) {
vq_err(vq, "Translation failure %d indirect idx %d\n",
@@ -1198,7 +1201,7 @@ static int get_indirect(struct vhost_dev *dev, struct vhost_virtqueue *vq,
* This function returns the descriptor number found, or vq->num (which is
* never a valid descriptor number) if none was found. A negative code is
* returned on error. */
-int vhost_get_vq_desc(struct vhost_dev *dev, struct vhost_virtqueue *vq,
+int vhost_get_vq_desc(struct vhost_virtqueue *vq,
struct iovec iov[], unsigned int iov_size,
unsigned int *out_num, unsigned int *in_num,
struct vhost_log *log, unsigned int *log_num)
@@ -1272,7 +1275,7 @@ int vhost_get_vq_desc(struct vhost_dev *dev, struct vhost_virtqueue *vq,
return -EFAULT;
}
if (desc.flags & VRING_DESC_F_INDIRECT) {
- ret = get_indirect(dev, vq, iov, iov_size,
+ ret = get_indirect(vq, iov, iov_size,
out_num, in_num,
log, log_num, &desc);
if (unlikely(ret < 0)) {
@@ -1283,7 +1286,7 @@ int vhost_get_vq_desc(struct vhost_dev *dev, struct vhost_virtqueue *vq,
continue;
}
- ret = translate_desc(dev, desc.addr, desc.len, iov + iov_count,
+ ret = translate_desc(vq, desc.addr, desc.len, iov + iov_count,
iov_size - iov_count);
if (unlikely(ret < 0)) {
vq_err(vq, "Translation failure %d descriptor idx %d\n",
@@ -1426,11 +1429,11 @@ static bool vhost_notify(struct vhost_dev *dev, struct vhost_virtqueue *vq)
* interrupts. */
smp_mb();
- if (vhost_has_feature(dev, VIRTIO_F_NOTIFY_ON_EMPTY) &&
+ if (vhost_has_feature(vq, VIRTIO_F_NOTIFY_ON_EMPTY) &&
unlikely(vq->avail_idx == vq->last_avail_idx))
return true;
- if (!vhost_has_feature(dev, VIRTIO_RING_F_EVENT_IDX)) {
+ if (!vhost_has_feature(vq, VIRTIO_RING_F_EVENT_IDX)) {
__u16 flags;
if (__get_user(flags, &vq->avail->flags)) {
vq_err(vq, "Failed to get flags");
@@ -1491,7 +1494,7 @@ bool vhost_enable_notify(struct vhost_dev *dev, struct vhost_virtqueue *vq)
if (!(vq->used_flags & VRING_USED_F_NO_NOTIFY))
return false;
vq->used_flags &= ~VRING_USED_F_NO_NOTIFY;
- if (!vhost_has_feature(dev, VIRTIO_RING_F_EVENT_IDX)) {
+ if (!vhost_has_feature(vq, VIRTIO_RING_F_EVENT_IDX)) {
r = vhost_update_used_flags(vq);
if (r) {
vq_err(vq, "Failed to enable notification at %p: %d\n",
@@ -1528,7 +1531,7 @@ void vhost_disable_notify(struct vhost_dev *dev, struct vhost_virtqueue *vq)
if (vq->used_flags & VRING_USED_F_NO_NOTIFY)
return;
vq->used_flags |= VRING_USED_F_NO_NOTIFY;
- if (!vhost_has_feature(dev, VIRTIO_RING_F_EVENT_IDX)) {
+ if (!vhost_has_feature(vq, VIRTIO_RING_F_EVENT_IDX)) {
r = vhost_update_used_flags(vq);
if (r)
vq_err(vq, "Failed to enable notification at %p: %d\n",
Copyright © 1996 – 2023 Jason A. Donenfeld. All Rights Reverse Engineered.