diff options
Diffstat (limited to 'drivers/virtio/virtio_ring.c')
-rw-r--r-- | drivers/virtio/virtio_ring.c | 9 |
1 files changed, 8 insertions, 1 deletions
diff --git a/drivers/virtio/virtio_ring.c b/drivers/virtio/virtio_ring.c index a882f260651..fbd2ecde93e 100644 --- a/drivers/virtio/virtio_ring.c +++ b/drivers/virtio/virtio_ring.c @@ -208,7 +208,11 @@ add_head: pr_debug("Added buffer head %i to %p\n", head, vq); END_USE(vq); - return 0; + + /* If we're indirect, we can fit many (assuming not OOM). */ + if (vq->indirect) + return vq->num_free ? vq->vring.num : 0; + return vq->num_free; } static void vring_kick(struct virtqueue *_vq) @@ -281,6 +285,9 @@ static void *vring_get_buf(struct virtqueue *_vq, unsigned int *len) return NULL; } + /* Only get used array entries after they have been exposed by host. */ + rmb(); + i = vq->vring.used->ring[vq->last_used_idx%vq->vring.num].id; *len = vq->vring.used->ring[vq->last_used_idx%vq->vring.num].len; |