| Message ID | 20180110160732.7722-4-gustavo@padovan.org (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On 01/10/18 17:07, Gustavo Padovan wrote: > From: Gustavo Padovan <gustavo.padovan@collabora.com> > > 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 s/and/or/ > 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. > > v5: > - keep using reserved2 field for cpia2 > - set fence_fd to 0 for now, for compat with userspace(Mauro) > > v4: > - make it a union with reserved2 and fence_fd (Hans Verkuil) > > v3: > - make the out_fence refer to the current buffer (Hans Verkuil) > > v2: add documentation > > Signed-off-by: Gustavo Padovan <gustavo.padovan@collabora.com> > --- > Documentation/media/uapi/v4l/buffer.rst | 15 +++++++++++++++ > drivers/media/common/videobuf/videobuf2-v4l2.c | 2 +- > drivers/media/v4l2-core/v4l2-compat-ioctl32.c | 4 ++-- > include/uapi/linux/videodev2.h | 7 ++++++- > 4 files changed, 24 insertions(+), 4 deletions(-) > > diff --git a/Documentation/media/uapi/v4l/buffer.rst b/Documentation/media/uapi/v4l/buffer.rst > index ae6ee73f151c..eeefbd2547e7 100644 > --- a/Documentation/media/uapi/v4l/buffer.rst > +++ b/Documentation/media/uapi/v4l/buffer.rst I'm missing documentation for the new fence_fd field in struct v4l2_buffer. Make sure to mention what value should be used if you don't set the IN_FENCE flag. > @@ -648,6 +648,21 @@ Buffer Flags > - Start Of Exposure. The buffer timestamp has been taken when the > exposure of the frame has begun. This is only valid for the > ``V4L2_BUF_TYPE_VIDEO_CAPTURE`` buffer type. > + * .. _`V4L2-BUF-FLAG-IN-FENCE`: > + > + - ``V4L2_BUF_FLAG_IN_FENCE`` > + - 0x00200000 > + - Ask V4L2 to wait on fence passed in ``fence_fd`` field. The buffer s/fence/the fence/ s/in/in the/ > + won't be queued to the driver until the fence signals. > + > + * .. _`V4L2-BUF-FLAG-OUT-FENCE`: > + > + - ``V4L2_BUF_FLAG_OUT_FENCE`` > + - 0x00400000 > + - Request a fence to be attached to the buffer. The ``fence_fd`` s/Request/Request for/ > + field on This very short line looks weird. > + :ref:`VIDIOC_QBUF` is used as a return argument to send the out-fence > + fd to userspace. I'd rephrase this: "The driver will fill in the out-fence fd in the ``fence_fd`` field when :ref:`VIDIOC_QBUF` returns." For both flags you also need to be explicit in mentioning that the application sets these flags before calling VIDIOC_QBUF. For other ioctls the driver just reports these flags. Also mention what happens if the fence can't be found or can't be created. Regards, Hans > > > > diff --git a/drivers/media/common/videobuf/videobuf2-v4l2.c b/drivers/media/common/videobuf/videobuf2-v4l2.c > index fac3cd6f901d..d838524a459e 100644 > --- a/drivers/media/common/videobuf/videobuf2-v4l2.c > +++ b/drivers/media/common/videobuf/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 = 0; > b->reserved = 0; > > if (q->is_multiplanar) { > diff --git a/drivers/media/v4l2-core/v4l2-compat-ioctl32.c b/drivers/media/v4l2-core/v4l2-compat-ioctl32.c > index e48d59046086..a11a0a2bed47 100644 > --- a/drivers/media/v4l2-core/v4l2-compat-ioctl32.c > +++ b/drivers/media/v4l2-core/v4l2-compat-ioctl32.c > @@ -370,7 +370,7 @@ struct v4l2_buffer32 { > __s32 fd; > } m; > __u32 length; > - __u32 reserved2; > + __s32 fence_fd; > __u32 reserved; > }; > > @@ -533,7 +533,7 @@ 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/include/uapi/linux/videodev2.h b/include/uapi/linux/videodev2.h > index 58894cfe9479..2d424aebdd1e 100644 > --- a/include/uapi/linux/videodev2.h > +++ b/include/uapi/linux/videodev2.h > @@ -933,7 +933,10 @@ struct v4l2_buffer { > __s32 fd; > } m; > __u32 length; > - __u32 reserved2; > + union { > + __s32 fence_fd; > + __u32 reserved2; > + }; > __u32 reserved; > }; > > @@ -970,6 +973,8 @@ 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 > > /** > * struct v4l2_exportbuffer - export of video buffer as DMABUF file descriptor >
On 01/10/18 17:07, Gustavo Padovan wrote: > From: Gustavo Padovan <gustavo.padovan@collabora.com> > > 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. > > v5: > - keep using reserved2 field for cpia2 > - set fence_fd to 0 for now, for compat with userspace(Mauro) > > v4: > - make it a union with reserved2 and fence_fd (Hans Verkuil) > > v3: > - make the out_fence refer to the current buffer (Hans Verkuil) > > v2: add documentation > > Signed-off-by: Gustavo Padovan <gustavo.padovan@collabora.com> > --- > Documentation/media/uapi/v4l/buffer.rst | 15 +++++++++++++++ > drivers/media/common/videobuf/videobuf2-v4l2.c | 2 +- > drivers/media/v4l2-core/v4l2-compat-ioctl32.c | 4 ++-- > include/uapi/linux/videodev2.h | 7 ++++++- > 4 files changed, 24 insertions(+), 4 deletions(-) > > diff --git a/Documentation/media/uapi/v4l/buffer.rst b/Documentation/media/uapi/v4l/buffer.rst > index ae6ee73f151c..eeefbd2547e7 100644 > --- a/Documentation/media/uapi/v4l/buffer.rst > +++ b/Documentation/media/uapi/v4l/buffer.rst > @@ -648,6 +648,21 @@ Buffer Flags > - Start Of Exposure. The buffer timestamp has been taken when the > exposure of the frame has begun. This is only valid for the > ``V4L2_BUF_TYPE_VIDEO_CAPTURE`` buffer type. > + * .. _`V4L2-BUF-FLAG-IN-FENCE`: > + > + - ``V4L2_BUF_FLAG_IN_FENCE`` > + - 0x00200000 > + - Ask V4L2 to wait on fence passed in ``fence_fd`` field. The buffer > + won't be queued to the driver until the fence signals. I'd also add: "The order in which buffers are queued is guaranteed to be preserved, so any buffers queued after this buffer will also be blocked until this fence signals." Regards, Hans > + > + * .. _`V4L2-BUF-FLAG-OUT-FENCE`: > + > + - ``V4L2_BUF_FLAG_OUT_FENCE`` > + - 0x00400000 > + - Request a fence to be attached to the buffer. The ``fence_fd`` > + field on > + :ref:`VIDIOC_QBUF` is used as a return argument to send the out-fence > + fd to userspace. > > > > diff --git a/drivers/media/common/videobuf/videobuf2-v4l2.c b/drivers/media/common/videobuf/videobuf2-v4l2.c > index fac3cd6f901d..d838524a459e 100644 > --- a/drivers/media/common/videobuf/videobuf2-v4l2.c > +++ b/drivers/media/common/videobuf/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 = 0; > b->reserved = 0; > > if (q->is_multiplanar) { > diff --git a/drivers/media/v4l2-core/v4l2-compat-ioctl32.c b/drivers/media/v4l2-core/v4l2-compat-ioctl32.c > index e48d59046086..a11a0a2bed47 100644 > --- a/drivers/media/v4l2-core/v4l2-compat-ioctl32.c > +++ b/drivers/media/v4l2-core/v4l2-compat-ioctl32.c > @@ -370,7 +370,7 @@ struct v4l2_buffer32 { > __s32 fd; > } m; > __u32 length; > - __u32 reserved2; > + __s32 fence_fd; > __u32 reserved; > }; > > @@ -533,7 +533,7 @@ 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/include/uapi/linux/videodev2.h b/include/uapi/linux/videodev2.h > index 58894cfe9479..2d424aebdd1e 100644 > --- a/include/uapi/linux/videodev2.h > +++ b/include/uapi/linux/videodev2.h > @@ -933,7 +933,10 @@ struct v4l2_buffer { > __s32 fd; > } m; > __u32 length; > - __u32 reserved2; > + union { > + __s32 fence_fd; > + __u32 reserved2; > + }; > __u32 reserved; > }; > > @@ -970,6 +973,8 @@ 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 > > /** > * struct v4l2_exportbuffer - export of video buffer as DMABUF file descriptor >
diff --git a/Documentation/media/uapi/v4l/buffer.rst b/Documentation/media/uapi/v4l/buffer.rst index ae6ee73f151c..eeefbd2547e7 100644 --- a/Documentation/media/uapi/v4l/buffer.rst +++ b/Documentation/media/uapi/v4l/buffer.rst @@ -648,6 +648,21 @@ Buffer Flags - Start Of Exposure. The buffer timestamp has been taken when the exposure of the frame has begun. This is only valid for the ``V4L2_BUF_TYPE_VIDEO_CAPTURE`` buffer type. + * .. _`V4L2-BUF-FLAG-IN-FENCE`: + + - ``V4L2_BUF_FLAG_IN_FENCE`` + - 0x00200000 + - Ask V4L2 to wait on fence passed in ``fence_fd`` field. The buffer + won't be queued to the driver until the fence signals. + + * .. _`V4L2-BUF-FLAG-OUT-FENCE`: + + - ``V4L2_BUF_FLAG_OUT_FENCE`` + - 0x00400000 + - Request a fence to be attached to the buffer. The ``fence_fd`` + field on + :ref:`VIDIOC_QBUF` is used as a return argument to send the out-fence + fd to userspace. diff --git a/drivers/media/common/videobuf/videobuf2-v4l2.c b/drivers/media/common/videobuf/videobuf2-v4l2.c index fac3cd6f901d..d838524a459e 100644 --- a/drivers/media/common/videobuf/videobuf2-v4l2.c +++ b/drivers/media/common/videobuf/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 = 0; b->reserved = 0; if (q->is_multiplanar) { diff --git a/drivers/media/v4l2-core/v4l2-compat-ioctl32.c b/drivers/media/v4l2-core/v4l2-compat-ioctl32.c index e48d59046086..a11a0a2bed47 100644 --- a/drivers/media/v4l2-core/v4l2-compat-ioctl32.c +++ b/drivers/media/v4l2-core/v4l2-compat-ioctl32.c @@ -370,7 +370,7 @@ struct v4l2_buffer32 { __s32 fd; } m; __u32 length; - __u32 reserved2; + __s32 fence_fd; __u32 reserved; }; @@ -533,7 +533,7 @@ 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/include/uapi/linux/videodev2.h b/include/uapi/linux/videodev2.h index 58894cfe9479..2d424aebdd1e 100644 --- a/include/uapi/linux/videodev2.h +++ b/include/uapi/linux/videodev2.h @@ -933,7 +933,10 @@ struct v4l2_buffer { __s32 fd; } m; __u32 length; - __u32 reserved2; + union { + __s32 fence_fd; + __u32 reserved2; + }; __u32 reserved; }; @@ -970,6 +973,8 @@ 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 /** * struct v4l2_exportbuffer - export of video buffer as DMABUF file descriptor