From 129134e5415d46f38b9978b3809af94ed649b57d Mon Sep 17 00:00:00 2001 From: Sergey Senozhatsky Date: Fri, 11 Sep 2020 05:07:58 +0200 Subject: media: media/v4l2: remove V4L2_FLAG_MEMORY_NON_CONSISTENT flag 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 reverts both kernel and user space parts: removes the DMA consistency attr functions, rolls back changes to v4l2_requestbuffers, v4l2_create_buffers structures and corresponding UAPI functions (plus compat32 layer) and cleans up the documentation. [hverkuil: fixed a few typos in the commit log] [hverkuil: fixed vb2_core_reqbufs call in drivers/media/dvb-core/dvb_vb2.c] [mchehab: fixed a typo in the commit log: revers->reverts] Signed-off-by: Christoph Hellwig Signed-off-by: Sergey Senozhatsky Signed-off-by: Hans Verkuil Signed-off-by: Mauro Carvalho Chehab --- Documentation/userspace-api/media/v4l/vidioc-reqbufs.rst | 12 ++---------- 1 file changed, 2 insertions(+), 10 deletions(-) (limited to 'Documentation/userspace-api/media/v4l/vidioc-reqbufs.rst') diff --git a/Documentation/userspace-api/media/v4l/vidioc-reqbufs.rst b/Documentation/userspace-api/media/v4l/vidioc-reqbufs.rst index 75d894d9c36c..0e3e2fde65e8 100644 --- a/Documentation/userspace-api/media/v4l/vidioc-reqbufs.rst +++ b/Documentation/userspace-api/media/v4l/vidioc-reqbufs.rst @@ -112,17 +112,10 @@ aborting or finishing any DMA in progress, an implicit ``V4L2_MEMORY_MMAP`` and ``type`` set to the buffer type. This will free any previously allocated buffers, so this is typically something that will be done at the start of the application. - * - union { - - (anonymous) - * - __u32 - - ``flags`` - - Specifies additional buffer management attributes. - See :ref:`memory-flags`. * - __u32 - ``reserved``\ [1] - - Kept for backwards compatibility. Use ``flags`` instead. - * - } - - + - A place holder for future extensions. Drivers and applications + must set the array to zero. .. tabularcolumns:: |p{6.1cm}|p{2.2cm}|p{8.7cm}| @@ -169,7 +162,6 @@ aborting or finishing any DMA in progress, an implicit - This capability is set by the driver to indicate that the queue supports cache and memory management hints. However, it's only valid when the queue is used for :ref:`memory mapping ` streaming I/O. See - :ref:`V4L2_FLAG_MEMORY_NON_CONSISTENT `, :ref:`V4L2_BUF_FLAG_NO_CACHE_INVALIDATE ` and :ref:`V4L2_BUF_FLAG_NO_CACHE_CLEAN `. -- cgit