Commit 9015fcc2 authored by Hans Verkuil's avatar Hans Verkuil Committed by Mauro Carvalho Chehab
Browse files

media: videobuf2-core: sanity checks for requests and qbuf 



The combination of supports_requests == 1 and min_buffers_needed > 0
is not allowed, WARN on that and return an error.

Also check that if vb2_core_qbuf() is called from req_queue, that it
doesn't return an error, unless it is -EIO.

Signed-off-by: default avatarHans Verkuil <hverkuil-cisco@xs4all.nl>
Cc: Paul Kocialkowski <paul.kocialkowski@bootlin.com>
Reviewed-by: default avatarEzequiel Garcia <ezequiel@collabora.com>
Signed-off-by: default avatarMauro Carvalho Chehab <mchehab+huawei@kernel.org>
parent b72dd0f3

drivers/media/common/videobuf2/videobuf2-core.c

+22 −1
Original line number Diff line number Diff line
@@ -1421,9 +1421,19 @@ int vb2_core_qbuf(struct vb2_queue *q, unsigned int index, void *pb, 
static void vb2_req_queue(struct media_request_object *obj)

{

	struct vb2_buffer *vb = container_of(obj, struct vb2_buffer, req_obj);

	int err;



	mutex_lock(vb->vb2_queue->lock);

	vb2_core_qbuf(vb->vb2_queue, vb->index, NULL, NULL);

	/*

	 * There is no method to propagate an error from vb2_core_qbuf(),

	 * so if this returns a non-0 value, then WARN.

	 *

	 * The only exception is -EIO which is returned if q->error is

	 * set. We just ignore that, and expect this will be caught the

	 * next time vb2_req_prepare() is called.

	 */

	err = vb2_core_qbuf(vb->vb2_queue, vb->index, NULL, NULL);

	WARN_ON_ONCE(err && err != -EIO);

	mutex_unlock(vb->vb2_queue->lock);

}
@@ -2342,6 +2352,17 @@ int vb2_core_queue_init(struct vb2_queue *q) 
	if (WARN_ON(q->requires_requests && !q->supports_requests))

		return -EINVAL;



	/*

	 * This combination is not allowed since a non-zero value of

	 * q->min_buffers_needed can cause vb2_core_qbuf() to fail if

	 * it has to call start_streaming(), and the Request API expects

	 * that queueing a request (and thus queueing a buffer contained

	 * in that request) will always succeed. There is no method of

	 * propagating an error back to userspace.

	 */

	if (WARN_ON(q->supports_requests && q->min_buffers_needed))

		return -EINVAL;



	INIT_LIST_HEAD(&q->queued_list);

	INIT_LIST_HEAD(&q->done_list);

	spin_lock_init(&q->done_lock);