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Diffstat (limited to 'drivers/vhost/vhost.c')
-rw-r--r--drivers/vhost/vhost.c57
1 files changed, 25 insertions, 32 deletions
diff --git a/drivers/vhost/vhost.c b/drivers/vhost/vhost.c
index a23870c..c90f437 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>
@@ -199,6 +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)
@@ -416,11 +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);
@@ -463,10 +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);
@@ -558,11 +563,7 @@ static int vq_access_ok(struct vhost_virtqueue *vq, 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);
@@ -571,12 +572,9 @@ EXPORT_SYMBOL_GPL(vhost_log_access_ok);
static int vq_log_access_ok(struct vhost_virtqueue *vq,
void __user *log_base)
{
- struct vhost_memory *mp;
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,
+ 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 +
@@ -619,15 +617,13 @@ static long vhost_set_memory(struct vhost_dev *d, struct vhost_memory __user *m)
kfree(newmem);
return -EFAULT;
}
- oldmem = rcu_dereference_protected(d->memory,
- lockdep_is_held(&d->mutex));
- rcu_assign_pointer(d->memory, newmem);
+ oldmem = d->memory;
+ d->memory = newmem;
- /* All memory accesses are done under some VQ mutex.
- * So below is a faster equivalent of synchronize_rcu()
- */
+ /* 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);
@@ -1054,7 +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;
@@ -1063,9 +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)) {
@@ -1087,7 +1081,6 @@ static int translate_desc(struct vhost_dev *dev, u64 addr, u32 len,
++ret;
}
- rcu_read_unlock();
return ret;
}
@@ -1112,7 +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,
@@ -1131,7 +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);
@@ -1171,7 +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",
@@ -1208,7 +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)
@@ -1282,7 +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)) {
@@ -1293,7 +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",
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