From: Jason Wang <jasow...@redhat.com> This patch introduces virtqueue_discard() to discard a descriptor and unmap the sgs. This will be used by the patch that will discard descriptor when packet is truncated.
Cc: Michael S. Tsirkin <m...@redhat.com> Signed-off-by: Jason Wang <jasow...@redhat.com> Reviewed-by: Michael S. Tsirkin <m...@redhat.com> Signed-off-by: Michael S. Tsirkin <m...@redhat.com> --- include/hw/virtio/virtio.h | 2 ++ hw/virtio/virtio.c | 7 +++++++ 2 files changed, 9 insertions(+) diff --git a/include/hw/virtio/virtio.h b/include/hw/virtio/virtio.h index 6201ee8..9d09115 100644 --- a/include/hw/virtio/virtio.h +++ b/include/hw/virtio/virtio.h @@ -146,6 +146,8 @@ void virtio_del_queue(VirtIODevice *vdev, int n); void virtqueue_push(VirtQueue *vq, const VirtQueueElement *elem, unsigned int len); void virtqueue_flush(VirtQueue *vq, unsigned int count); +void virtqueue_discard(VirtQueue *vq, const VirtQueueElement *elem, + unsigned int len); void virtqueue_fill(VirtQueue *vq, const VirtQueueElement *elem, unsigned int len, unsigned int idx); diff --git a/hw/virtio/virtio.c b/hw/virtio/virtio.c index 6f2b96c..d0bc72e 100644 --- a/hw/virtio/virtio.c +++ b/hw/virtio/virtio.c @@ -267,6 +267,13 @@ static void virtqueue_unmap_sg(VirtQueue *vq, const VirtQueueElement *elem, 0, elem->out_sg[i].iov_len); } +void virtqueue_discard(VirtQueue *vq, const VirtQueueElement *elem, + unsigned int len) +{ + vq->last_avail_idx--; + virtqueue_unmap_sg(vq, elem, len); +} + void virtqueue_fill(VirtQueue *vq, const VirtQueueElement *elem, unsigned int len, unsigned int idx) { -- MST