Em Fri, 16 Jun 2017 16:39:04 +0900
Gustavo Padovan <gustavo@xxxxxxxxxxx> escreveu:
> From: Gustavo Padovan <gustavo.padovan@xxxxxxxxxxxxx>
>
> Turn the reserved2 field into fence_fd that we will use to send
> an in-fence to the kernel and return an out-fence from the kernel to
> userspace.
>
> Two new flags were added, V4L2_BUF_FLAG_IN_FENCE, that should be used
> when sending a fence to the kernel to be waited on, and
> V4L2_BUF_FLAG_OUT_FENCE, to ask the kernel to give back an out-fence.
>
> Signed-off-by: Gustavo Padovan <gustavo.padovan@xxxxxxxxxxxxx>
> ---
> drivers/media/v4l2-core/v4l2-compat-ioctl32.c | 4 ++--
> drivers/media/v4l2-core/videobuf2-v4l2.c | 2 +-
> include/uapi/linux/videodev2.h | 4 +++-
> 3 files changed, 6 insertions(+), 4 deletions(-)
>
> diff --git a/drivers/media/v4l2-core/v4l2-compat-ioctl32.c b/drivers/media/v4l2-core/v4l2-compat-ioctl32.c
> index 6f52970..8f6ab85 100644
> --- a/drivers/media/v4l2-core/v4l2-compat-ioctl32.c
> +++ b/drivers/media/v4l2-core/v4l2-compat-ioctl32.c
> @@ -367,7 +367,7 @@ struct v4l2_buffer32 {
> __s32 fd;
> } m;
> __u32 length;
> - __u32 reserved2;
> + __s32 fence_fd;
> __u32 reserved;
> };
>
> @@ -530,7 +530,7 @@ static int put_v4l2_buffer32(struct v4l2_buffer *kp, struct v4l2_buffer32 __user
> put_user(kp->timestamp.tv_usec, &up->timestamp.tv_usec) ||
> copy_to_user(&up->timecode, &kp->timecode, sizeof(struct v4l2_timecode)) ||
> put_user(kp->sequence, &up->sequence) ||
> - put_user(kp->reserved2, &up->reserved2) ||
> + put_user(kp->fence_fd, &up->fence_fd) ||
> put_user(kp->reserved, &up->reserved) ||
> put_user(kp->length, &up->length))
> return -EFAULT;
> diff --git a/drivers/media/v4l2-core/videobuf2-v4l2.c b/drivers/media/v4l2-core/videobuf2-v4l2.c
> index 0c06699..110fb45 100644
> --- a/drivers/media/v4l2-core/videobuf2-v4l2.c
> +++ b/drivers/media/v4l2-core/videobuf2-v4l2.c
> @@ -203,7 +203,7 @@ static void __fill_v4l2_buffer(struct vb2_buffer *vb, void *pb)
> b->timestamp = ns_to_timeval(vb->timestamp);
> b->timecode = vbuf->timecode;
> b->sequence = vbuf->sequence;
> - b->reserved2 = 0;
> + b->fence_fd = -1;
> b->reserved = 0;
>
> if (q->is_multiplanar) {
> diff --git a/include/uapi/linux/videodev2.h b/include/uapi/linux/videodev2.h
> index 2b8feb8..750d511 100644
> --- a/include/uapi/linux/videodev2.h
> +++ b/include/uapi/linux/videodev2.h
> @@ -916,7 +916,7 @@ struct v4l2_buffer {
> __s32 fd;
> } m;
> __u32 length;
> - __u32 reserved2;
> + __s32 fence_fd;
> __u32 reserved;
> };
>
> @@ -953,6 +953,8 @@ struct v4l2_buffer {
> #define V4L2_BUF_FLAG_TSTAMP_SRC_SOE 0x00010000
> /* mem2mem encoder/decoder */
> #define V4L2_BUF_FLAG_LAST 0x00100000
> +#define V4L2_BUF_FLAG_IN_FENCE 0x00200000
> +#define V4L2_BUF_FLAG_OUT_FENCE 0x00400000
Please document them at Documentation/media/uapi/v4l/buffer.rst.
We'll also need a new chapter at the documentation, describing the
explicit fences mechanism.
>
> /**
> * struct v4l2_exportbuffer - export of video buffer as DMABUF file descriptor
--
Thanks,
Mauro
