virtio: rename virtqueue_discard to virtqueue_unpop

The function undoes the effect of virtqueue_pop and doesn't do anything
destructive or irreversible so virtqueue_unpop is a more fitting name.
Signed-off-by: NLadi Prosek <lprosek@redhat.com>
Reviewed-by: NStefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: NMichael S. Tsirkin <mst@redhat.com>
Signed-off-by: NMichael S. Tsirkin <mst@redhat.com>

hw/net/virtio-net.c

@@ -1177,7 +1177,7 @@ static ssize_t virtio_net_receive(NetClientState *nc, const uint8_t *buf, size_t
          * must have consumed the complete packet.
          * Otherwise, drop it. */
         if (!n->mergeable_rx_bufs && offset < size) {
-            virtqueue_discard(q->rx_vq, elem, total);
+            virtqueue_unpop(q->rx_vq, elem, total);
             g_free(elem);
             return size;
         }

hw/virtio/virtio-balloon.c

@@ -456,7 +456,7 @@ static void virtio_balloon_device_reset(VirtIODevice *vdev)
     VirtIOBalloon *s = VIRTIO_BALLOON(vdev);
 
     if (s->stats_vq_elem != NULL) {
-        virtqueue_discard(s->svq, s->stats_vq_elem, 0);
+        virtqueue_unpop(s->svq, s->stats_vq_elem, 0);
         g_free(s->stats_vq_elem);
         s->stats_vq_elem = NULL;
     }

hw/virtio/virtio.c

@@ -279,7 +279,7 @@ void virtqueue_detach_element(VirtQueue *vq, const VirtQueueElement *elem,
     virtqueue_unmap_sg(vq, elem, len);
 }
 
-/* virtqueue_discard:
+/* virtqueue_unpop:
  * @vq: The #VirtQueue
  * @elem: The #VirtQueueElement
  * @len: number of bytes written
@@ -287,8 +287,8 @@ void virtqueue_detach_element(VirtQueue *vq, const VirtQueueElement *elem,
  * Pretend the most recent element wasn't popped from the virtqueue.  The next
  * call to virtqueue_pop() will refetch the element.
  */
-void virtqueue_discard(VirtQueue *vq, const VirtQueueElement *elem,
-                       unsigned int len)
+void virtqueue_unpop(VirtQueue *vq, const VirtQueueElement *elem,
+                     unsigned int len)
 {
     vq->last_avail_idx--;
     virtqueue_detach_element(vq, elem, len);
@@ -301,7 +301,7 @@ void virtqueue_discard(VirtQueue *vq, const VirtQueueElement *elem,
  * Pretend that elements weren't popped from the virtqueue.  The next
  * virtqueue_pop() will refetch the oldest element.
  *
- * Use virtqueue_discard() instead if you have a VirtQueueElement.
+ * Use virtqueue_unpop() instead if you have a VirtQueueElement.
  *
  * Returns: true on success, false if @num is greater than the number of in use
  * elements.

include/hw/virtio/virtio.h

@@ -160,8 +160,8 @@ void virtqueue_push(VirtQueue *vq, const VirtQueueElement *elem,
 void virtqueue_flush(VirtQueue *vq, unsigned int count);
 void virtqueue_detach_element(VirtQueue *vq, const VirtQueueElement *elem,
                               unsigned int len);
-void virtqueue_discard(VirtQueue *vq, const VirtQueueElement *elem,
-                       unsigned int len);
+void virtqueue_unpop(VirtQueue *vq, const VirtQueueElement *elem,
+                     unsigned int len);
 bool virtqueue_rewind(VirtQueue *vq, unsigned int num);
 void virtqueue_fill(VirtQueue *vq, const VirtQueueElement *elem,
                     unsigned int len, unsigned int idx);