Re: [PATCH] media: media videobuf2: Stop direct calls to queue num_buffers field

[Hans Verkuil]

On 1/18/24 12:22, Tomasz Figa wrote:
> On Tue, Jan 16, 2024 at 6:32 PM Benjamin Gaignard
> <benjamin.gaignard@xxxxxxxxxxxxx> wrote:
>>
>>
>> Le 16/01/2024 à 10:21, Hans Verkuil a écrit :
>>> On 15/01/2024 18:08, Benjamin Gaignard wrote:
>>>> Use vb2_get_num_buffers() to avoid using queue num_buffers field directly.
>>>> This allows us to change how the number of buffers is computed in the
>>>> future.
>>>>
>>>> Fixes: c838530d230b ("media: media videobuf2: Be more flexible on the number of queue stored buffers")
>>>> Signed-off-by: Benjamin Gaignard <benjamin.gaignard@xxxxxxxxxxxxx>
>>>> ---
>>>>   drivers/media/common/videobuf2/videobuf2-core.c | 2 +-
>>>>   1 file changed, 1 insertion(+), 1 deletion(-)
>>>>
>>>> diff --git a/drivers/media/common/videobuf2/videobuf2-core.c b/drivers/media/common/videobuf2/videobuf2-core.c
>>>> index 41a832dd1426..b6bf8f232f48 100644
>>>> --- a/drivers/media/common/videobuf2/videobuf2-core.c
>>>> +++ b/drivers/media/common/videobuf2/videobuf2-core.c
>>>> @@ -989,7 +989,7 @@ int vb2_core_create_bufs(struct vb2_queue *q, enum vb2_memory memory,
>>>>      bool no_previous_buffers = !q_num_bufs;
>>>>      int ret = 0;
>>>>
>>>> -    if (q->num_buffers == q->max_num_buffers) {
>>>> +    if (q_num_bufs == q->max_num_buffers) {
>>>>              dprintk(q, 1, "maximum number of buffers already allocated\n");
>>>>              return -ENOBUFS;
>>>>      }
>>> There is another case in vb2_ioctl_create_bufs() where num_buffers is accessed directly.
>>> Can you fix that one as well?
>>
>> It is removed by the patch I have send just after this one:
>> "media: core: Refactor vb2_ioctl_create_bufs() to always set capabilities flags"
> 
> I'd prefer that to be also included in this fix, so that it's all
> logically grouped together. Actually Hans also ended up including that
> change in his patch, without the commit message mentioning it.

Yeah, it's borderline. But I think it is better if this patch updates both
places, and then I'll make a v2 for my patch on top.

Regards,

	Hans

> 
> Best regards,
> Tomasz