Subject: Re: [PATCH 01/18] media/v4l2: remove V4L2-FLAG-MEMORY-NON-CONSISTENT flag

From: Tomasz Figa <[email-masked]>
Date: Fri, 25 Sep 2020 18:47:12 +0000

Hi Christoph,

On Tue, Sep 15, 2020 at 05:51:05PM +0200, Christoph Hellwig wrote:
> From: Sergey Senozhatsky <[email-masked]>
> 
> The patch partially reverts some of the UAPI bits of the buffer
> cache management hints. Namely, the queue consistency (memory
> coherency) user-space hint because, as it turned out, the kernel
> implementation of this feature was misusing DMA_ATTR_NON_CONSISTENT.
> 
> The patch revers both kernel and user space parts: removes the
> DMA consistency attr functions, rollbacks changes to v4l2_requestbuffers,
> v4l2_create_buffers structures and corresponding UAPI functions
> (plus compat32 layer) and cleanups the documentation.
> 
> Signed-off-by: Christoph Hellwig <[email-masked]>
> Signed-off-by: Sergey Senozhatsky <[email-masked]>
> Signed-off-by: Christoph Hellwig <[email-masked]>
> ---
>  .../userspace-api/media/v4l/buffer.rst        | 17 -------
>  .../media/v4l/vidioc-create-bufs.rst          |  6 +--
>  .../media/v4l/vidioc-reqbufs.rst              | 12 +----
>  .../media/common/videobuf2/videobuf2-core.c   | 46 +++----------------
>  .../common/videobuf2/videobuf2-dma-contig.c   | 19 --------
>  .../media/common/videobuf2/videobuf2-dma-sg.c |  3 +-
>  .../media/common/videobuf2/videobuf2-v4l2.c   | 18 +-------
>  drivers/media/v4l2-core/v4l2-compat-ioctl32.c | 10 +---
>  drivers/media/v4l2-core/v4l2-ioctl.c          |  5 +-
>  include/media/videobuf2-core.h                |  7 +--
>  include/uapi/linux/videodev2.h                | 13 +-----
>  11 files changed, 22 insertions(+), 134 deletions(-)

Acked-by: Tomasz Figa <[email-masked]>

Best regards,
Tomasz