virtqueue: fix invalidate wrong cache region

It always invalidates the avail ring index 0. It must get the right vring index before incalidating it. Signed-off-by: Joshua Lin <[email protected]>
OpenAMP · Feb 2, 2022 · 02f8ec8 · 02f8ec8
1 parent 792d269
commit 02f8ec8
Showing 1 changed file with 4 additions and 4 deletions.
diff --git a/lib/virtio/virtqueue.c b/lib/virtio/virtqueue.c
@@ -271,10 +271,10 @@ void *virtqueue_get_available_buffer(struct virtqueue *vq, uint16_t *avail_idx,
 
  VQUEUE_BUSY(vq);
 
+ head_idx = vq->vq_available_idx++ & (vq->vq_nentries - 1);
+
  /* Avail.ring is updated by master, invalidate it */
  VRING_INVALIDATE(vq->vq_ring.avail->ring[head_idx]);
-
- head_idx = vq->vq_available_idx++ & (vq->vq_nentries - 1);
  *avail_idx = vq->vq_ring.avail->ring[head_idx];
 
  /* Invalidate the desc entry written by master before accessing it */
@@ -453,10 +453,10 @@ uint32_t virtqueue_get_desc_size(struct virtqueue *vq)
 
  VQUEUE_BUSY(vq);
 
+ head_idx = vq->vq_available_idx & (vq->vq_nentries - 1);
+
  /* Avail.ring is updated by master, invalidate it */
  VRING_INVALIDATE(vq->vq_ring.avail->ring[head_idx]);
-
- head_idx = vq->vq_available_idx & (vq->vq_nentries - 1);
  avail_idx = vq->vq_ring.avail->ring[head_idx];
 
  /* Invalidate the desc entry written by master before accessing it */