From f9bfbebf34eab707b065116cdc9699d25ba4252a Mon Sep 17 00:00:00 2001 From: Shirley Ma Date: Fri, 29 Jan 2010 03:19:05 +0000 Subject: virtio: Add ability to detach unused buffers from vrings There's currently no way for a virtio driver to ask for unused buffers, so it has to keep a list itself to reclaim them at shutdown. This is redundant, since virtio_ring stores that information. So add a new hook to do this. Signed-off-by: Shirley Ma Signed-off-by: Amit Shah Signed-off-by: Rusty Russell Signed-off-by: David S. Miller --- include/linux/virtio.h | 4 ++++ 1 file changed, 4 insertions(+) (limited to 'include') diff --git a/include/linux/virtio.h b/include/linux/virtio.h index 057a2e010758..f508c651e53d 100644 --- a/include/linux/virtio.h +++ b/include/linux/virtio.h @@ -51,6 +51,9 @@ struct virtqueue { * This re-enables callbacks; it returns "false" if there are pending * buffers in the queue, to detect a possible race between the driver * checking for more work, and enabling callbacks. + * @detach_unused_buf: detach first unused buffer + * vq: the struct virtqueue we're talking about. + * Returns NULL or the "data" token handed to add_buf * * Locking rules are straightforward: the driver is responsible for * locking. No two operations may be invoked simultaneously, with the exception @@ -71,6 +74,7 @@ struct virtqueue_ops { void (*disable_cb)(struct virtqueue *vq); bool (*enable_cb)(struct virtqueue *vq); + void *(*detach_unused_buf)(struct virtqueue *vq); }; /** -- cgit v1.2.3