diff options
| -rw-r--r-- | hw/virtio/virtio.c | 27 | ||||
| -rw-r--r-- | include/hw/virtio/virtio.h | 2 |
2 files changed, 27 insertions, 2 deletions
diff --git a/hw/virtio/virtio.c b/hw/virtio/virtio.c index 18ce333457..46f79c9e14 100644 --- a/hw/virtio/virtio.c +++ b/hw/virtio/virtio.c @@ -264,12 +264,35 @@ static void virtqueue_unmap_sg(VirtQueue *vq, const VirtQueueElement *elem, 0, elem->out_sg[i].iov_len); } +/* virtqueue_detach_element: + * @vq: The #VirtQueue + * @elem: The #VirtQueueElement + * @len: number of bytes written + * + * Detach the element from the virtqueue. This function is suitable for device + * reset or other situations where a #VirtQueueElement is simply freed and will + * not be pushed or discarded. + */ +void virtqueue_detach_element(VirtQueue *vq, const VirtQueueElement *elem, + unsigned int len) +{ + vq->inuse--; + virtqueue_unmap_sg(vq, elem, len); +} + +/* virtqueue_discard: + * @vq: The #VirtQueue + * @elem: The #VirtQueueElement + * @len: number of bytes written + * + * 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) { vq->last_avail_idx--; - vq->inuse--; - virtqueue_unmap_sg(vq, elem, len); + virtqueue_detach_element(vq, elem, len); } /* virtqueue_rewind: diff --git a/include/hw/virtio/virtio.h b/include/hw/virtio/virtio.h index 888c8debe6..e25ec4f0b5 100644 --- a/include/hw/virtio/virtio.h +++ b/include/hw/virtio/virtio.h @@ -155,6 +155,8 @@ void *virtqueue_alloc_element(size_t sz, unsigned out_num, unsigned in_num); void virtqueue_push(VirtQueue *vq, const VirtQueueElement *elem, unsigned int len); 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); bool virtqueue_rewind(VirtQueue *vq, unsigned int num); |