media: videobuf2: handle V4L2_MEMORY_FLAG_NON_COHERENT flag

This patch lets user-space request a non-coherent memory
allocation during CREATE_BUFS and REQBUFS ioctl calls.

= CREATE_BUFS

  struct v4l2_create_buffers has seven 4-byte reserved areas,
  so reserved[0] is renamed to ->flags. The struct, thus, now
  has six reserved 4-byte regions.

= CREATE_BUFS32

  struct v4l2_create_buffers32 has seven 4-byte reserved areas,
  so reserved[0] is renamed to ->flags. The struct, thus, now
  has six reserved 4-byte regions.

= REQBUFS

 We use one byte of a 4 byte ->reserved[1] member of struct
 v4l2_requestbuffers. The struct, thus, now has reserved 3 bytes.

Signed-off-by: Sergey Senozhatsky <senozhatsky@chromium.org>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
This commit is contained in:
Sergey Senozhatsky 2021-09-09 13:24:29 +02:00 committed by Mauro Carvalho Chehab
parent b00a9e59c5
commit c0acf9cfee
7 changed files with 60 additions and 15 deletions

View file

@ -959,7 +959,8 @@ struct v4l2_requestbuffers {
__u32 type; /* enum v4l2_buf_type */
__u32 memory; /* enum v4l2_memory */
__u32 capabilities;
__u32 reserved[1];
__u8 flags;
__u8 reserved[3];
};
#define V4L2_MEMORY_FLAG_NON_COHERENT (1 << 0)
@ -2507,6 +2508,9 @@ struct v4l2_dbg_chip_info {
* @memory: enum v4l2_memory; buffer memory type
* @format: frame format, for which buffers are requested
* @capabilities: capabilities of this buffer type.
* @flags: additional buffer management attributes (ignored unless the
* queue has V4L2_BUF_CAP_SUPPORTS_MMAP_CACHE_HINTS capability
* and configured for MMAP streaming I/O).
* @reserved: future extensions
*/
struct v4l2_create_buffers {
@ -2515,7 +2519,8 @@ struct v4l2_create_buffers {
__u32 memory;
struct v4l2_format format;
__u32 capabilities;
__u32 reserved[7];
__u32 flags;
__u32 reserved[6];
};
/*