Commit b7ef5367 authored by Ricardo Ribalda's avatar Ricardo Ribalda Committed by Hans Verkuil
Browse files

media: uvcvideo: Handle locks in uvc_queue_return_buffers 



Most of the calls to uvc_queue_return_buffers() wrap the call with
spin_lock_irq()/spin_unlock_irq().

Rename uvc_queue_return_buffers to __uvc_queue_return_buffers to
indicate that this is the version that does not handle locks and create
a new version of the function that handles the lock.

Reviewed-by: default avatarHans de Goede <hansg@kernel.org>
Signed-off-by: default avatarRicardo Ribalda <ribalda@chromium.org>
Link: https://lore.kernel.org/r/20250616-uvc-fop-v4-2-250286570ee7@chromium.org


Reviewed-by: default avatarHans Verkuil <hverkuil@xs4all.nl>
Signed-off-by: default avatarHans de Goede <hansg@kernel.org>
Signed-off-by: default avatarHans Verkuil <hverkuil@xs4all.nl>
parent c93d73c9

drivers/media/usb/uvc/uvc_queue.c

+13 −7
Original line number Diff line number Diff line
@@ -42,13 +42,15 @@ static inline struct uvc_buffer *uvc_vbuf_to_buffer(struct vb2_v4l2_buffer *buf) 
 *

 * This function must be called with the queue spinlock held.

 */

static void uvc_queue_return_buffers(struct uvc_video_queue *queue,

static void __uvc_queue_return_buffers(struct uvc_video_queue *queue,

				       enum uvc_buffer_state state)

{

	enum vb2_buffer_state vb2_state = state == UVC_BUF_STATE_ERROR

					? VB2_BUF_STATE_ERROR

					: VB2_BUF_STATE_QUEUED;



	lockdep_assert_held(&queue->irqlock);



	while (!list_empty(&queue->irqqueue)) {

		struct uvc_buffer *buf = list_first_entry(&queue->irqqueue,

							  struct uvc_buffer,
@@ -59,6 +61,14 @@ static void uvc_queue_return_buffers(struct uvc_video_queue *queue, 
	}

}



static void uvc_queue_return_buffers(struct uvc_video_queue *queue,

				     enum uvc_buffer_state state)

{

	spin_lock_irq(&queue->irqlock);

	__uvc_queue_return_buffers(queue, state);

	spin_unlock_irq(&queue->irqlock);

}



/* -----------------------------------------------------------------------------

 * videobuf2 queue operations

 */
@@ -171,9 +181,7 @@ static int uvc_start_streaming(struct vb2_queue *vq, unsigned int count) 
	if (ret == 0)

		return 0;



	spin_lock_irq(&queue->irqlock);

	uvc_queue_return_buffers(queue, UVC_BUF_STATE_QUEUED);

	spin_unlock_irq(&queue->irqlock);



	return ret;

}
@@ -187,9 +195,7 @@ static void uvc_stop_streaming(struct vb2_queue *vq) 
	if (vq->type != V4L2_BUF_TYPE_META_CAPTURE)

		uvc_video_stop_streaming(uvc_queue_to_stream(queue));



	spin_lock_irq(&queue->irqlock);

	uvc_queue_return_buffers(queue, UVC_BUF_STATE_ERROR);

	spin_unlock_irq(&queue->irqlock);

}



static const struct vb2_ops uvc_queue_qops = {
@@ -263,7 +269,7 @@ void uvc_queue_cancel(struct uvc_video_queue *queue, int disconnect) 
	unsigned long flags;



	spin_lock_irqsave(&queue->irqlock, flags);

	uvc_queue_return_buffers(queue, UVC_BUF_STATE_ERROR);

	__uvc_queue_return_buffers(queue, UVC_BUF_STATE_ERROR);

	/*

	 * This must be protected by the irqlock spinlock to avoid race

	 * conditions between uvc_buffer_queue and the disconnection event that