On 15/01/2024 18:08, Benjamin Gaignard wrote:
> vb2_create_bufs() takes care of setting V4L2_BUF_CAP_SUPPORTS_MAX_NUM_BUFFERS
> flag and vb2_queue max_num_buffers field so call it instead duplicate the
> same code in vb2_ioctl_create_bufs(). Testing p->count after calling
> vb2_create_bufs() is safe since the function also check it.
>
> Fixes: d055a76c0065 ("media: core: Report the maximum possible number of buffers for the queue")
> Signed-off-by: Benjamin Gaignard <benjamin.gaignard@xxxxxxxxxxxxx>
> ---
> .../media/common/videobuf2/videobuf2-v4l2.c | 23 ++++++++++---------
> 1 file changed, 12 insertions(+), 11 deletions(-)
>
> diff --git a/drivers/media/common/videobuf2/videobuf2-v4l2.c b/drivers/media/common/videobuf2/videobuf2-v4l2.c
> index 54d572c3b515..bf304a7234a0 100644
> --- a/drivers/media/common/videobuf2/videobuf2-v4l2.c
> +++ b/drivers/media/common/videobuf2/videobuf2-v4l2.c
> @@ -1029,23 +1029,24 @@ int vb2_ioctl_create_bufs(struct file *file, void *priv,
> int res = vb2_verify_memory_type(vdev->queue, p->memory,
> p->format.type);
>
> - p->index = vdev->queue->num_buffers;
> - fill_buf_caps(vdev->queue, &p->capabilities);
> - validate_memory_flags(vdev->queue, p->memory, &p->flags);
> + if (vb2_queue_is_busy(vdev->queue, file)) {
> + res = -EBUSY;
> + goto failed;
> + }
> +
> + res = vb2_create_bufs(vdev->queue, p);
> + if (res == 0)
> + vdev->queue->owner = file->private_data;
This would set owner when called with p->count == 0, but that's
not what you want.
I decided to make an attempt at this myself, I'll post a patch.
Regards,
Hans
> +
> +failed:
> /*
> * If count == 0, then just check if memory and type are valid.
> - * Any -EBUSY result from vb2_verify_memory_type can be mapped to 0.
> + * Any -EBUSY result from vb2_verify_memory_type() or
> + * vb2_queue_is_busy() can be mapped to 0.
> */
> if (p->count == 0)
> return res != -EBUSY ? res : 0;
> - if (res)
> - return res;
> - if (vb2_queue_is_busy(vdev->queue, file))
> - return -EBUSY;
>
> - res = vb2_create_bufs(vdev->queue, p);
> - if (res == 0)
> - vdev->queue->owner = file->private_data;
> return res;
> }
> EXPORT_SYMBOL_GPL(vb2_ioctl_create_bufs);
