This patch adds extension to V4L2 api. It allow to export a mmap buffer as file descriptor. New ioctl VIDIOC_EXPBUF is added. It takes a buffer offset used by mmap and return a file descriptor on success.
Signed-off-by: Tomasz Stanislawski t.stanislaws@samsung.com Signed-off-by: Kyungmin Park kyungmin.park@samsung.com --- drivers/media/video/v4l2-compat-ioctl32.c | 1 + drivers/media/video/v4l2-dev.c | 1 + drivers/media/video/v4l2-ioctl.c | 6 ++++++ include/linux/videodev2.h | 26 ++++++++++++++++++++++++++ include/media/v4l2-ioctl.h | 2 ++ 5 files changed, 36 insertions(+)
diff --git a/drivers/media/video/v4l2-compat-ioctl32.c b/drivers/media/video/v4l2-compat-ioctl32.c index 5327ad3..45159d9 100644 --- a/drivers/media/video/v4l2-compat-ioctl32.c +++ b/drivers/media/video/v4l2-compat-ioctl32.c @@ -954,6 +954,7 @@ long v4l2_compat_ioctl32(struct file *file, unsigned int cmd, unsigned long arg) case VIDIOC_S_FBUF32: case VIDIOC_OVERLAY32: case VIDIOC_QBUF32: + case VIDIOC_EXPBUF: case VIDIOC_DQBUF32: case VIDIOC_STREAMON32: case VIDIOC_STREAMOFF32: diff --git a/drivers/media/video/v4l2-dev.c b/drivers/media/video/v4l2-dev.c index 5ccbd46..6bf6307 100644 --- a/drivers/media/video/v4l2-dev.c +++ b/drivers/media/video/v4l2-dev.c @@ -597,6 +597,7 @@ static void determine_valid_ioctls(struct video_device *vdev) SET_VALID_IOCTL(ops, VIDIOC_REQBUFS, vidioc_reqbufs); SET_VALID_IOCTL(ops, VIDIOC_QUERYBUF, vidioc_querybuf); SET_VALID_IOCTL(ops, VIDIOC_QBUF, vidioc_qbuf); + SET_VALID_IOCTL(ops, VIDIOC_EXPBUF, vidioc_expbuf); SET_VALID_IOCTL(ops, VIDIOC_DQBUF, vidioc_dqbuf); SET_VALID_IOCTL(ops, VIDIOC_OVERLAY, vidioc_overlay); SET_VALID_IOCTL(ops, VIDIOC_G_FBUF, vidioc_g_fbuf); diff --git a/drivers/media/video/v4l2-ioctl.c b/drivers/media/video/v4l2-ioctl.c index 31fc2ad..a73b14e 100644 --- a/drivers/media/video/v4l2-ioctl.c +++ b/drivers/media/video/v4l2-ioctl.c @@ -212,6 +212,7 @@ static struct v4l2_ioctl_info v4l2_ioctls[] = { IOCTL_INFO(VIDIOC_S_FBUF, INFO_FL_PRIO), IOCTL_INFO(VIDIOC_OVERLAY, INFO_FL_PRIO), IOCTL_INFO(VIDIOC_QBUF, 0), + IOCTL_INFO(VIDIOC_EXPBUF, 0), IOCTL_INFO(VIDIOC_DQBUF, 0), IOCTL_INFO(VIDIOC_STREAMON, INFO_FL_PRIO), IOCTL_INFO(VIDIOC_STREAMOFF, INFO_FL_PRIO), @@ -957,6 +958,11 @@ static long __video_do_ioctl(struct file *file, dbgbuf(cmd, vfd, p); break; } + case VIDIOC_EXPBUF: + { + ret = ops->vidioc_expbuf(file, fh, arg); + break; + } case VIDIOC_DQBUF: { struct v4l2_buffer *p = arg; diff --git a/include/linux/videodev2.h b/include/linux/videodev2.h index 51b20f4..e8893a5 100644 --- a/include/linux/videodev2.h +++ b/include/linux/videodev2.h @@ -684,6 +684,31 @@ struct v4l2_buffer { #define V4L2_BUF_FLAG_NO_CACHE_INVALIDATE 0x0800 #define V4L2_BUF_FLAG_NO_CACHE_CLEAN 0x1000
+/** + * struct v4l2_exportbuffer - export of video buffer as DMABUF file descriptor + * + * @fd: file descriptor associated with DMABUF (set by driver) + * @mem_offset: buffer memory offset as returned by VIDIOC_QUERYBUF in struct + * v4l2_buffer::m.offset (for single-plane formats) or + * v4l2_plane::m.offset (for multi-planar formats) + * @flags: flags for newly created file, currently only O_CLOEXEC is + * supported, refer to manual of open syscall for more details + * + * Contains data used for exporting a video buffer as DMABUF file descriptor. + * The buffer is identified by a 'cookie' returned by VIDIOC_QUERYBUF + * (identical to the cookie used to mmap() the buffer to userspace). All + * reserved fields must be set to zero. The field reserved0 is expected to + * become a structure 'type' allowing an alternative layout of the structure + * content. Therefore this field should not be used for any other extensions. + */ +struct v4l2_exportbuffer { + __u32 fd; + __u32 reserved0; + __u32 mem_offset; + __u32 flags; + __u32 reserved[12]; +}; + /* * O V E R L A Y P R E V I E W */ @@ -2553,6 +2578,7 @@ struct v4l2_create_buffers { #define VIDIOC_S_FBUF _IOW('V', 11, struct v4l2_framebuffer) #define VIDIOC_OVERLAY _IOW('V', 14, int) #define VIDIOC_QBUF _IOWR('V', 15, struct v4l2_buffer) +#define VIDIOC_EXPBUF _IOWR('V', 16, struct v4l2_exportbuffer) #define VIDIOC_DQBUF _IOWR('V', 17, struct v4l2_buffer) #define VIDIOC_STREAMON _IOW('V', 18, int) #define VIDIOC_STREAMOFF _IOW('V', 19, int) diff --git a/include/media/v4l2-ioctl.h b/include/media/v4l2-ioctl.h index d8b76f7..ccd1faa 100644 --- a/include/media/v4l2-ioctl.h +++ b/include/media/v4l2-ioctl.h @@ -119,6 +119,8 @@ struct v4l2_ioctl_ops { int (*vidioc_reqbufs) (struct file *file, void *fh, struct v4l2_requestbuffers *b); int (*vidioc_querybuf)(struct file *file, void *fh, struct v4l2_buffer *b); int (*vidioc_qbuf) (struct file *file, void *fh, struct v4l2_buffer *b); + int (*vidioc_expbuf) (struct file *file, void *fh, + struct v4l2_exportbuffer *e); int (*vidioc_dqbuf) (struct file *file, void *fh, struct v4l2_buffer *b);
int (*vidioc_create_bufs)(struct file *file, void *fh, struct v4l2_create_buffers *b);