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path: root/drivers/vhost/vhost.c
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Diffstat (limited to 'drivers/vhost/vhost.c')
-rw-r--r--drivers/vhost/vhost.c99
1 files changed, 85 insertions, 14 deletions
diff --git a/drivers/vhost/vhost.c b/drivers/vhost/vhost.c
index 4c5625cb540c..2383caf88b67 100644
--- a/drivers/vhost/vhost.c
+++ b/drivers/vhost/vhost.c
@@ -1646,13 +1646,87 @@ static int log_write(void __user *log_base,
return r;
}
+static int log_write_hva(struct vhost_virtqueue *vq, u64 hva, u64 len)
+{
+ struct vhost_umem *umem = vq->umem;
+ struct vhost_umem_node *u;
+ u64 start, end, l, min;
+ int r;
+ bool hit = false;
+
+ while (len) {
+ min = len;
+ /* More than one GPAs can be mapped into a single HVA. So
+ * iterate all possible umems here to be safe.
+ */
+ list_for_each_entry(u, &umem->umem_list, link) {
+ if (u->userspace_addr > hva - 1 + len ||
+ u->userspace_addr - 1 + u->size < hva)
+ continue;
+ start = max(u->userspace_addr, hva);
+ end = min(u->userspace_addr - 1 + u->size,
+ hva - 1 + len);
+ l = end - start + 1;
+ r = log_write(vq->log_base,
+ u->start + start - u->userspace_addr,
+ l);
+ if (r < 0)
+ return r;
+ hit = true;
+ min = min(l, min);
+ }
+
+ if (!hit)
+ return -EFAULT;
+
+ len -= min;
+ hva += min;
+ }
+
+ return 0;
+}
+
+static int log_used(struct vhost_virtqueue *vq, u64 used_offset, u64 len)
+{
+ struct iovec iov[64];
+ int i, ret;
+
+ if (!vq->iotlb)
+ return log_write(vq->log_base, vq->log_addr + used_offset, len);
+
+ ret = translate_desc(vq, (uintptr_t)vq->used + used_offset,
+ len, iov, 64, VHOST_ACCESS_WO);
+ if (ret < 0)
+ return ret;
+
+ for (i = 0; i < ret; i++) {
+ ret = log_write_hva(vq, (uintptr_t)iov[i].iov_base,
+ iov[i].iov_len);
+ if (ret)
+ return ret;
+ }
+
+ return 0;
+}
+
int vhost_log_write(struct vhost_virtqueue *vq, struct vhost_log *log,
- unsigned int log_num, u64 len)
+ unsigned int log_num, u64 len, struct iovec *iov, int count)
{
int i, r;
/* Make sure data written is seen before log. */
smp_wmb();
+
+ if (vq->iotlb) {
+ for (i = 0; i < count; i++) {
+ r = log_write_hva(vq, (uintptr_t)iov[i].iov_base,
+ iov[i].iov_len);
+ if (r < 0)
+ return r;
+ }
+ return 0;
+ }
+
for (i = 0; i < log_num; ++i) {
u64 l = min(log[i].len, len);
r = log_write(vq->log_base, log[i].addr, l);
@@ -1682,9 +1756,8 @@ static int vhost_update_used_flags(struct vhost_virtqueue *vq)
smp_wmb();
/* Log used flag write. */
used = &vq->used->flags;
- log_write(vq->log_base, vq->log_addr +
- (used - (void __user *)vq->used),
- sizeof vq->used->flags);
+ log_used(vq, (used - (void __user *)vq->used),
+ sizeof vq->used->flags);
if (vq->log_ctx)
eventfd_signal(vq->log_ctx, 1);
}
@@ -1702,9 +1775,8 @@ static int vhost_update_avail_event(struct vhost_virtqueue *vq, u16 avail_event)
smp_wmb();
/* Log avail event write */
used = vhost_avail_event(vq);
- log_write(vq->log_base, vq->log_addr +
- (used - (void __user *)vq->used),
- sizeof *vhost_avail_event(vq));
+ log_used(vq, (used - (void __user *)vq->used),
+ sizeof *vhost_avail_event(vq));
if (vq->log_ctx)
eventfd_signal(vq->log_ctx, 1);
}
@@ -2103,10 +2175,8 @@ static int __vhost_add_used_n(struct vhost_virtqueue *vq,
/* Make sure data is seen before log. */
smp_wmb();
/* Log used ring entry write. */
- log_write(vq->log_base,
- vq->log_addr +
- ((void __user *)used - (void __user *)vq->used),
- count * sizeof *used);
+ log_used(vq, ((void __user *)used - (void __user *)vq->used),
+ count * sizeof *used);
}
old = vq->last_used_idx;
new = (vq->last_used_idx += count);
@@ -2145,10 +2215,11 @@ int vhost_add_used_n(struct vhost_virtqueue *vq, struct vring_used_elem *heads,
return -EFAULT;
}
if (unlikely(vq->log_used)) {
+ /* Make sure used idx is seen before log. */
+ smp_wmb();
/* Log used index update. */
- log_write(vq->log_base,
- vq->log_addr + offsetof(struct vring_used, idx),
- sizeof vq->used->idx);
+ log_used(vq, offsetof(struct vring_used, idx),
+ sizeof vq->used->idx);
if (vq->log_ctx)
eventfd_signal(vq->log_ctx, 1);
}