| Message ID | 20200204025641.218376-6-senozhatsky@chromium.org (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | Implement V4L2_BUF_FLAG_NO_CACHE_* flags | expand |
On 2/4/20 3:56 AM, Sergey Senozhatsky wrote: > This patch lets user-space to request a non-consistent 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. > > = REQBUFS > > We use one bit of a ->reserved[1] member of struct v4l2_requestbuffers, > which is now renamed to ->flags. Unlike v4l2_create_buffers, struct > v4l2_requestbuffers does not have enough reserved room. Therefore for > backward compatibility ->reserved and ->flags were put into anonymous > union. > > Change-Id: I0eaab3428de499ce1bce6fc6b26c5ca5ff405882 > Signed-off-by: Sergey Senozhatsky <senozhatsky@chromium.org> > --- > .../media/uapi/v4l/vidioc-create-bufs.rst | 9 +++++++- > .../media/uapi/v4l/vidioc-reqbufs.rst | 15 ++++++++++--- > .../media/common/videobuf2/videobuf2-v4l2.c | 21 ++++++++++++++++--- > drivers/media/v4l2-core/v4l2-ioctl.c | 5 +---- > include/uapi/linux/videodev2.h | 8 +++++-- > 5 files changed, 45 insertions(+), 13 deletions(-) > > diff --git a/Documentation/media/uapi/v4l/vidioc-create-bufs.rst b/Documentation/media/uapi/v4l/vidioc-create-bufs.rst > index bd08e4f77ae4..68185e94b686 100644 > --- a/Documentation/media/uapi/v4l/vidioc-create-bufs.rst > +++ b/Documentation/media/uapi/v4l/vidioc-create-bufs.rst > @@ -121,7 +121,14 @@ than the number requested. > other changes, then set ``count`` to 0, ``memory`` to > ``V4L2_MEMORY_MMAP`` and ``format.type`` to the buffer type. > * - __u32 > - - ``reserved``\ [7] > + - ``flags`` > + - Specifies additional buffer management attributes. Valid only when > + queue reports :ref:`V4L2_BUF_CAP_SUPPORTS_CACHE_HINTS` capability. > + Old drivers and applications must set it to zero. Drop the 'Valid only' sentence. The V4L2_FLAG_MEMORY_NON_CONSISTENT depends on that capability, but other flags added in the future may not. Inside add a reference to the memory flags section created in patch 3. > + > + > + * - __u32 > + - ``reserved``\ [6] > - A place holder for future extensions. Drivers and applications > must set the array to zero. > > diff --git a/Documentation/media/uapi/v4l/vidioc-reqbufs.rst b/Documentation/media/uapi/v4l/vidioc-reqbufs.rst > index d0c643db477a..9741dac0d5b3 100644 > --- a/Documentation/media/uapi/v4l/vidioc-reqbufs.rst > +++ b/Documentation/media/uapi/v4l/vidioc-reqbufs.rst > @@ -112,10 +112,19 @@ 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. > - * - __u32 > + * - union > + - (anonymous) > + * - > + - __u32 > + - ``flags``\ [1] > + - Specifies additional buffer management attributes. Valid only when > + queue reports :ref:`V4L2_BUF_CAP_SUPPORTS_CACHE_HINTS` capability. Same comment as above. > + Old drivers and applications must set it to zero. > + > + * - > + - __u32 > - ``reserved``\ [1] > - - A place holder for future extensions. Drivers and applications > - must set the array to zero. > + - Kept for backwards compatibility. Use ``flags`` instead. > > .. tabularcolumns:: |p{6.1cm}|p{2.2cm}|p{8.7cm}| > > diff --git a/drivers/media/common/videobuf2/videobuf2-v4l2.c b/drivers/media/common/videobuf2/videobuf2-v4l2.c > index 7cdfcd1baf82..eb5d1306cb03 100644 > --- a/drivers/media/common/videobuf2/videobuf2-v4l2.c > +++ b/drivers/media/common/videobuf2/videobuf2-v4l2.c > @@ -707,9 +707,15 @@ static void fill_buf_caps(struct vb2_queue *q, u32 *caps) > int vb2_reqbufs(struct vb2_queue *q, struct v4l2_requestbuffers *req) > { > int ret = vb2_verify_memory_type(q, req->memory, req->type); > + bool consistent = true; > + > + if (req->flags & V4L2_FLAG_MEMORY_NON_CONSISTENT) > + consistent = false; > > fill_buf_caps(q, &req->capabilities); > - return ret ? ret : vb2_core_reqbufs(q, req->memory, true, &req->count); > + if (ret) > + return ret; > + return vb2_core_reqbufs(q, req->memory, consistent, &req->count); > } > EXPORT_SYMBOL_GPL(vb2_reqbufs); > > @@ -738,6 +744,7 @@ int vb2_create_bufs(struct vb2_queue *q, struct v4l2_create_buffers *create) > unsigned requested_sizes[VIDEO_MAX_PLANES]; > struct v4l2_format *f = &create->format; > int ret = vb2_verify_memory_type(q, create->memory, f->type); > + bool consistent = true; > unsigned i; > > fill_buf_caps(q, &create->capabilities); > @@ -783,7 +790,11 @@ int vb2_create_bufs(struct vb2_queue *q, struct v4l2_create_buffers *create) > for (i = 0; i < requested_planes; i++) > if (requested_sizes[i] == 0) > return -EINVAL; > - return ret ? ret : vb2_core_create_bufs(q, create->memory, true, > + > + if (create->flags & V4L2_FLAG_MEMORY_NON_CONSISTENT) > + consistent = false; > + > + return ret ? ret : vb2_core_create_bufs(q, create->memory, consistent, > &create->count, requested_planes, requested_sizes); > } > EXPORT_SYMBOL_GPL(vb2_create_bufs); > @@ -953,13 +964,17 @@ int vb2_ioctl_reqbufs(struct file *file, void *priv, > { > struct video_device *vdev = video_devdata(file); > int res = vb2_verify_memory_type(vdev->queue, p->memory, p->type); > + bool consistent = true; > > fill_buf_caps(vdev->queue, &p->capabilities); > if (res) > return res; > if (vb2_queue_is_busy(vdev, file)) > return -EBUSY; > - res = vb2_core_reqbufs(vdev->queue, p->memory, true, &p->count); > + if (p->flags & V4L2_FLAG_MEMORY_NON_CONSISTENT) > + consistent = false; > + > + res = vb2_core_reqbufs(vdev->queue, p->memory, consistent, &p->count); > /* If count == 0, then the owner has released all buffers and he > is no longer owner of the queue. Otherwise we have a new owner. */ > if (res == 0) > diff --git a/drivers/media/v4l2-core/v4l2-ioctl.c b/drivers/media/v4l2-core/v4l2-ioctl.c > index aaf83e254272..9791e2882382 100644 > --- a/drivers/media/v4l2-core/v4l2-ioctl.c > +++ b/drivers/media/v4l2-core/v4l2-ioctl.c > @@ -1973,9 +1973,6 @@ static int v4l_reqbufs(const struct v4l2_ioctl_ops *ops, > > if (ret) > return ret; > - > - CLEAR_AFTER_FIELD(p, capabilities); > - > return ops->vidioc_reqbufs(file, fh, p); > } > > @@ -2015,7 +2012,7 @@ static int v4l_create_bufs(const struct v4l2_ioctl_ops *ops, > if (ret) > return ret; > > - CLEAR_AFTER_FIELD(create, capabilities); > + CLEAR_AFTER_FIELD(create, flags); > > v4l_sanitize_format(&create->format); > > diff --git a/include/uapi/linux/videodev2.h b/include/uapi/linux/videodev2.h > index 72efc1c544cd..169a8cf345ed 100644 > --- a/include/uapi/linux/videodev2.h > +++ b/include/uapi/linux/videodev2.h > @@ -938,7 +938,10 @@ struct v4l2_requestbuffers { > __u32 type; /* enum v4l2_buf_type */ > __u32 memory; /* enum v4l2_memory */ > __u32 capabilities; > - __u32 reserved[1]; > + union { > + __u32 flags; > + __u32 reserved[1]; > + }; How about this: __u8 flags; __u8 reserved[3]; That avoids the anonymous union and allows some space for future additions. Regards, Hans > }; > > /* capabilities for struct v4l2_requestbuffers and v4l2_create_buffers */ > @@ -2445,7 +2448,8 @@ struct v4l2_create_buffers { > __u32 memory; > struct v4l2_format format; > __u32 capabilities; > - __u32 reserved[7]; > + __u32 flags; > + __u32 reserved[6]; > }; > > /* >
On 2/4/20 3:56 AM, Sergey Senozhatsky wrote: > This patch lets user-space to request a non-consistent 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. > > = REQBUFS > > We use one bit of a ->reserved[1] member of struct v4l2_requestbuffers, > which is now renamed to ->flags. Unlike v4l2_create_buffers, struct > v4l2_requestbuffers does not have enough reserved room. Therefore for > backward compatibility ->reserved and ->flags were put into anonymous > union. > > Change-Id: I0eaab3428de499ce1bce6fc6b26c5ca5ff405882 > Signed-off-by: Sergey Senozhatsky <senozhatsky@chromium.org> > --- > .../media/uapi/v4l/vidioc-create-bufs.rst | 9 +++++++- > .../media/uapi/v4l/vidioc-reqbufs.rst | 15 ++++++++++--- > .../media/common/videobuf2/videobuf2-v4l2.c | 21 ++++++++++++++++--- > drivers/media/v4l2-core/v4l2-ioctl.c | 5 +---- > include/uapi/linux/videodev2.h | 8 +++++-- > 5 files changed, 45 insertions(+), 13 deletions(-) > > diff --git a/Documentation/media/uapi/v4l/vidioc-create-bufs.rst b/Documentation/media/uapi/v4l/vidioc-create-bufs.rst > index bd08e4f77ae4..68185e94b686 100644 > --- a/Documentation/media/uapi/v4l/vidioc-create-bufs.rst > +++ b/Documentation/media/uapi/v4l/vidioc-create-bufs.rst > @@ -121,7 +121,14 @@ than the number requested. > other changes, then set ``count`` to 0, ``memory`` to > ``V4L2_MEMORY_MMAP`` and ``format.type`` to the buffer type. > * - __u32 > - - ``reserved``\ [7] > + - ``flags`` > + - Specifies additional buffer management attributes. Valid only when > + queue reports :ref:`V4L2_BUF_CAP_SUPPORTS_CACHE_HINTS` capability. > + Old drivers and applications must set it to zero. > + > + > + * - __u32 > + - ``reserved``\ [6] > - A place holder for future extensions. Drivers and applications > must set the array to zero. > > diff --git a/Documentation/media/uapi/v4l/vidioc-reqbufs.rst b/Documentation/media/uapi/v4l/vidioc-reqbufs.rst > index d0c643db477a..9741dac0d5b3 100644 > --- a/Documentation/media/uapi/v4l/vidioc-reqbufs.rst > +++ b/Documentation/media/uapi/v4l/vidioc-reqbufs.rst > @@ -112,10 +112,19 @@ 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. > - * - __u32 > + * - union > + - (anonymous) > + * - > + - __u32 > + - ``flags``\ [1] > + - Specifies additional buffer management attributes. Valid only when > + queue reports :ref:`V4L2_BUF_CAP_SUPPORTS_CACHE_HINTS` capability. > + Old drivers and applications must set it to zero. > + > + * - > + - __u32 > - ``reserved``\ [1] > - - A place holder for future extensions. Drivers and applications > - must set the array to zero. > + - Kept for backwards compatibility. Use ``flags`` instead. > > .. tabularcolumns:: |p{6.1cm}|p{2.2cm}|p{8.7cm}| > > diff --git a/drivers/media/common/videobuf2/videobuf2-v4l2.c b/drivers/media/common/videobuf2/videobuf2-v4l2.c > index 7cdfcd1baf82..eb5d1306cb03 100644 > --- a/drivers/media/common/videobuf2/videobuf2-v4l2.c > +++ b/drivers/media/common/videobuf2/videobuf2-v4l2.c > @@ -707,9 +707,15 @@ static void fill_buf_caps(struct vb2_queue *q, u32 *caps) > int vb2_reqbufs(struct vb2_queue *q, struct v4l2_requestbuffers *req) > { > int ret = vb2_verify_memory_type(q, req->memory, req->type); > + bool consistent = true; > + > + if (req->flags & V4L2_FLAG_MEMORY_NON_CONSISTENT) > + consistent = false; There is no check against allow_cache_hints: if that's 0, then the V4L2_FLAG_MEMORY_NON_CONSISTENT flag should be cleared since it is not supported. > > fill_buf_caps(q, &req->capabilities); > - return ret ? ret : vb2_core_reqbufs(q, req->memory, true, &req->count); > + if (ret) > + return ret; > + return vb2_core_reqbufs(q, req->memory, consistent, &req->count); > } > EXPORT_SYMBOL_GPL(vb2_reqbufs); > > @@ -738,6 +744,7 @@ int vb2_create_bufs(struct vb2_queue *q, struct v4l2_create_buffers *create) > unsigned requested_sizes[VIDEO_MAX_PLANES]; > struct v4l2_format *f = &create->format; > int ret = vb2_verify_memory_type(q, create->memory, f->type); > + bool consistent = true; > unsigned i; > > fill_buf_caps(q, &create->capabilities); > @@ -783,7 +790,11 @@ int vb2_create_bufs(struct vb2_queue *q, struct v4l2_create_buffers *create) > for (i = 0; i < requested_planes; i++) > if (requested_sizes[i] == 0) > return -EINVAL; > - return ret ? ret : vb2_core_create_bufs(q, create->memory, true, > + > + if (create->flags & V4L2_FLAG_MEMORY_NON_CONSISTENT) > + consistent = false; Ditto. Regards, Hans > + > + return ret ? ret : vb2_core_create_bufs(q, create->memory, consistent, > &create->count, requested_planes, requested_sizes); > } > EXPORT_SYMBOL_GPL(vb2_create_bufs); > @@ -953,13 +964,17 @@ int vb2_ioctl_reqbufs(struct file *file, void *priv, > { > struct video_device *vdev = video_devdata(file); > int res = vb2_verify_memory_type(vdev->queue, p->memory, p->type); > + bool consistent = true; > > fill_buf_caps(vdev->queue, &p->capabilities); > if (res) > return res; > if (vb2_queue_is_busy(vdev, file)) > return -EBUSY; > - res = vb2_core_reqbufs(vdev->queue, p->memory, true, &p->count); > + if (p->flags & V4L2_FLAG_MEMORY_NON_CONSISTENT) > + consistent = false; > + > + res = vb2_core_reqbufs(vdev->queue, p->memory, consistent, &p->count); > /* If count == 0, then the owner has released all buffers and he > is no longer owner of the queue. Otherwise we have a new owner. */ > if (res == 0) > diff --git a/drivers/media/v4l2-core/v4l2-ioctl.c b/drivers/media/v4l2-core/v4l2-ioctl.c > index aaf83e254272..9791e2882382 100644 > --- a/drivers/media/v4l2-core/v4l2-ioctl.c > +++ b/drivers/media/v4l2-core/v4l2-ioctl.c > @@ -1973,9 +1973,6 @@ static int v4l_reqbufs(const struct v4l2_ioctl_ops *ops, > > if (ret) > return ret; > - > - CLEAR_AFTER_FIELD(p, capabilities); > - > return ops->vidioc_reqbufs(file, fh, p); > } > > @@ -2015,7 +2012,7 @@ static int v4l_create_bufs(const struct v4l2_ioctl_ops *ops, > if (ret) > return ret; > > - CLEAR_AFTER_FIELD(create, capabilities); > + CLEAR_AFTER_FIELD(create, flags); > > v4l_sanitize_format(&create->format); > > diff --git a/include/uapi/linux/videodev2.h b/include/uapi/linux/videodev2.h > index 72efc1c544cd..169a8cf345ed 100644 > --- a/include/uapi/linux/videodev2.h > +++ b/include/uapi/linux/videodev2.h > @@ -938,7 +938,10 @@ struct v4l2_requestbuffers { > __u32 type; /* enum v4l2_buf_type */ > __u32 memory; /* enum v4l2_memory */ > __u32 capabilities; > - __u32 reserved[1]; > + union { > + __u32 flags; > + __u32 reserved[1]; > + }; > }; > > /* capabilities for struct v4l2_requestbuffers and v4l2_create_buffers */ > @@ -2445,7 +2448,8 @@ struct v4l2_create_buffers { > __u32 memory; > struct v4l2_format format; > __u32 capabilities; > - __u32 reserved[7]; > + __u32 flags; > + __u32 reserved[6]; > }; > > /* >
On (20/02/19 09:25), Hans Verkuil wrote: [..] > > diff --git a/Documentation/media/uapi/v4l/vidioc-create-bufs.rst b/Documentation/media/uapi/v4l/vidioc-create-bufs.rst > > index bd08e4f77ae4..68185e94b686 100644 > > --- a/Documentation/media/uapi/v4l/vidioc-create-bufs.rst > > +++ b/Documentation/media/uapi/v4l/vidioc-create-bufs.rst > > @@ -121,7 +121,14 @@ than the number requested. > > other changes, then set ``count`` to 0, ``memory`` to > > ``V4L2_MEMORY_MMAP`` and ``format.type`` to the buffer type. > > * - __u32 > > - - ``reserved``\ [7] > > + - ``flags`` > > + - Specifies additional buffer management attributes. Valid only when > > + queue reports :ref:`V4L2_BUF_CAP_SUPPORTS_CACHE_HINTS` capability. > > + Old drivers and applications must set it to zero. > > Drop the 'Valid only' sentence. The V4L2_FLAG_MEMORY_NON_CONSISTENT depends > on that capability, but other flags added in the future may not. The whole sentence, right? > Inside add a reference to the memory flags section created in patch 3. Sorry. Inside? [..] > > diff --git a/include/uapi/linux/videodev2.h b/include/uapi/linux/videodev2.h > > index 72efc1c544cd..169a8cf345ed 100644 > > --- a/include/uapi/linux/videodev2.h > > +++ b/include/uapi/linux/videodev2.h > > @@ -938,7 +938,10 @@ struct v4l2_requestbuffers { > > __u32 type; /* enum v4l2_buf_type */ > > __u32 memory; /* enum v4l2_memory */ > > __u32 capabilities; > > - __u32 reserved[1]; > > + union { > > + __u32 flags; > > + __u32 reserved[1]; > > + }; > > How about this: > > __u8 flags; > __u8 reserved[3]; > > That avoids the anonymous union and allows some space for future additions. Hmm. This way old apps, which clear out ->reserved, e.g. memset(&x.reserved, 0x00, sizeof(x.reserved)), won't clear out x.flags and can accidentally submit some unintended garbage. It's not the case with anon union. -ss
On 2/19/20 9:59 AM, Sergey Senozhatsky wrote: > On (20/02/19 09:25), Hans Verkuil wrote: > [..] >>> diff --git a/Documentation/media/uapi/v4l/vidioc-create-bufs.rst b/Documentation/media/uapi/v4l/vidioc-create-bufs.rst >>> index bd08e4f77ae4..68185e94b686 100644 >>> --- a/Documentation/media/uapi/v4l/vidioc-create-bufs.rst >>> +++ b/Documentation/media/uapi/v4l/vidioc-create-bufs.rst >>> @@ -121,7 +121,14 @@ than the number requested. >>> other changes, then set ``count`` to 0, ``memory`` to >>> ``V4L2_MEMORY_MMAP`` and ``format.type`` to the buffer type. >>> * - __u32 >>> - - ``reserved``\ [7] >>> + - ``flags`` >>> + - Specifies additional buffer management attributes. Valid only when >>> + queue reports :ref:`V4L2_BUF_CAP_SUPPORTS_CACHE_HINTS` capability. >>> + Old drivers and applications must set it to zero. >> >> Drop the 'Valid only' sentence. The V4L2_FLAG_MEMORY_NON_CONSISTENT depends >> on that capability, but other flags added in the future may not. > > The whole sentence, right? Yes, "Valid only ... capability." > >> Inside add a reference to the memory flags section created in patch 3. > > Sorry. Inside? Oops: Inside -> Instead > > [..] >>> diff --git a/include/uapi/linux/videodev2.h b/include/uapi/linux/videodev2.h >>> index 72efc1c544cd..169a8cf345ed 100644 >>> --- a/include/uapi/linux/videodev2.h >>> +++ b/include/uapi/linux/videodev2.h >>> @@ -938,7 +938,10 @@ struct v4l2_requestbuffers { >>> __u32 type; /* enum v4l2_buf_type */ >>> __u32 memory; /* enum v4l2_memory */ >>> __u32 capabilities; >>> - __u32 reserved[1]; >>> + union { >>> + __u32 flags; >>> + __u32 reserved[1]; >>> + }; >> >> How about this: >> >> __u8 flags; >> __u8 reserved[3]; >> >> That avoids the anonymous union and allows some space for future additions. > > Hmm. This way old apps, which clear out ->reserved, e.g. > memset(&x.reserved, 0x00, sizeof(x.reserved)), won't clear > out x.flags and can accidentally submit some unintended > garbage. It's not the case with anon union. Hmm. I need to think about this some more, so leave in the anon union for now. Regards, Hans > > -ss >
On (20/02/19 09:48), Hans Verkuil wrote: [..] > > int vb2_reqbufs(struct vb2_queue *q, struct v4l2_requestbuffers *req) > > { > > int ret = vb2_verify_memory_type(q, req->memory, req->type); > > + bool consistent = true; > > + > > + if (req->flags & V4L2_FLAG_MEMORY_NON_CONSISTENT) > > + consistent = false; > > There is no check against allow_cache_hints: if that's 0, then > the V4L2_FLAG_MEMORY_NON_CONSISTENT flag should be cleared since it is > not supported. The check is in set_queue_consistency() static void set_queue_consistency(struct vb2_queue *q, bool consistent_mem) { if (!q->allow_cache_hints) return; if (consistent_mem) q->dma_attrs &= ~DMA_ATTR_NON_CONSISTENT; else q->dma_attrs |= DMA_ATTR_NON_CONSISTENT; } I don't explicitly clear DMA_ATTR_NON_CONSISTENT attr for !->allow_cache_hints queues just in case if the driver for some reason sets that flag. ->allow_cache_hints is, thus, only for cases when user-space asks us to set or clear it. -ss
On 2/19/20 10:05 AM, Sergey Senozhatsky wrote: > On (20/02/19 09:48), Hans Verkuil wrote: > [..] >>> int vb2_reqbufs(struct vb2_queue *q, struct v4l2_requestbuffers *req) >>> { >>> int ret = vb2_verify_memory_type(q, req->memory, req->type); >>> + bool consistent = true; >>> + >>> + if (req->flags & V4L2_FLAG_MEMORY_NON_CONSISTENT) >>> + consistent = false; >> >> There is no check against allow_cache_hints: if that's 0, then >> the V4L2_FLAG_MEMORY_NON_CONSISTENT flag should be cleared since it is >> not supported. > > The check is in set_queue_consistency() That's the check against the functionality. I'm talking about the API level: if !q->allow_cache_hints, then clear V4L2_FLAG_MEMORY_NON_CONSISTENT from req->flags so that, when the ioctl returns to userspace, the application can tell that that flag was rejected. Regards, Hans > > static void set_queue_consistency(struct vb2_queue *q, bool consistent_mem) > { > if (!q->allow_cache_hints) > return; > > if (consistent_mem) > q->dma_attrs &= ~DMA_ATTR_NON_CONSISTENT; > else > q->dma_attrs |= DMA_ATTR_NON_CONSISTENT; > } > > I don't explicitly clear DMA_ATTR_NON_CONSISTENT attr for > !->allow_cache_hints queues just in case if the driver for > some reason sets that flag. ->allow_cache_hints is, thus, > only for cases when user-space asks us to set or clear it. > > -ss >
diff --git a/Documentation/media/uapi/v4l/vidioc-create-bufs.rst b/Documentation/media/uapi/v4l/vidioc-create-bufs.rst index bd08e4f77ae4..68185e94b686 100644 --- a/Documentation/media/uapi/v4l/vidioc-create-bufs.rst +++ b/Documentation/media/uapi/v4l/vidioc-create-bufs.rst @@ -121,7 +121,14 @@ than the number requested. other changes, then set ``count`` to 0, ``memory`` to ``V4L2_MEMORY_MMAP`` and ``format.type`` to the buffer type. * - __u32 - - ``reserved``\ [7] + - ``flags`` + - Specifies additional buffer management attributes. Valid only when + queue reports :ref:`V4L2_BUF_CAP_SUPPORTS_CACHE_HINTS` capability. + Old drivers and applications must set it to zero. + + + * - __u32 + - ``reserved``\ [6] - A place holder for future extensions. Drivers and applications must set the array to zero. diff --git a/Documentation/media/uapi/v4l/vidioc-reqbufs.rst b/Documentation/media/uapi/v4l/vidioc-reqbufs.rst index d0c643db477a..9741dac0d5b3 100644 --- a/Documentation/media/uapi/v4l/vidioc-reqbufs.rst +++ b/Documentation/media/uapi/v4l/vidioc-reqbufs.rst @@ -112,10 +112,19 @@ 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. - * - __u32 + * - union + - (anonymous) + * - + - __u32 + - ``flags``\ [1] + - Specifies additional buffer management attributes. Valid only when + queue reports :ref:`V4L2_BUF_CAP_SUPPORTS_CACHE_HINTS` capability. + Old drivers and applications must set it to zero. + + * - + - __u32 - ``reserved``\ [1] - - A place holder for future extensions. Drivers and applications - must set the array to zero. + - Kept for backwards compatibility. Use ``flags`` instead. .. tabularcolumns:: |p{6.1cm}|p{2.2cm}|p{8.7cm}| diff --git a/drivers/media/common/videobuf2/videobuf2-v4l2.c b/drivers/media/common/videobuf2/videobuf2-v4l2.c index 7cdfcd1baf82..eb5d1306cb03 100644 --- a/drivers/media/common/videobuf2/videobuf2-v4l2.c +++ b/drivers/media/common/videobuf2/videobuf2-v4l2.c @@ -707,9 +707,15 @@ static void fill_buf_caps(struct vb2_queue *q, u32 *caps) int vb2_reqbufs(struct vb2_queue *q, struct v4l2_requestbuffers *req) { int ret = vb2_verify_memory_type(q, req->memory, req->type); + bool consistent = true; + + if (req->flags & V4L2_FLAG_MEMORY_NON_CONSISTENT) + consistent = false; fill_buf_caps(q, &req->capabilities); - return ret ? ret : vb2_core_reqbufs(q, req->memory, true, &req->count); + if (ret) + return ret; + return vb2_core_reqbufs(q, req->memory, consistent, &req->count); } EXPORT_SYMBOL_GPL(vb2_reqbufs); @@ -738,6 +744,7 @@ int vb2_create_bufs(struct vb2_queue *q, struct v4l2_create_buffers *create) unsigned requested_sizes[VIDEO_MAX_PLANES]; struct v4l2_format *f = &create->format; int ret = vb2_verify_memory_type(q, create->memory, f->type); + bool consistent = true; unsigned i; fill_buf_caps(q, &create->capabilities); @@ -783,7 +790,11 @@ int vb2_create_bufs(struct vb2_queue *q, struct v4l2_create_buffers *create) for (i = 0; i < requested_planes; i++) if (requested_sizes[i] == 0) return -EINVAL; - return ret ? ret : vb2_core_create_bufs(q, create->memory, true, + + if (create->flags & V4L2_FLAG_MEMORY_NON_CONSISTENT) + consistent = false; + + return ret ? ret : vb2_core_create_bufs(q, create->memory, consistent, &create->count, requested_planes, requested_sizes); } EXPORT_SYMBOL_GPL(vb2_create_bufs); @@ -953,13 +964,17 @@ int vb2_ioctl_reqbufs(struct file *file, void *priv, { struct video_device *vdev = video_devdata(file); int res = vb2_verify_memory_type(vdev->queue, p->memory, p->type); + bool consistent = true; fill_buf_caps(vdev->queue, &p->capabilities); if (res) return res; if (vb2_queue_is_busy(vdev, file)) return -EBUSY; - res = vb2_core_reqbufs(vdev->queue, p->memory, true, &p->count); + if (p->flags & V4L2_FLAG_MEMORY_NON_CONSISTENT) + consistent = false; + + res = vb2_core_reqbufs(vdev->queue, p->memory, consistent, &p->count); /* If count == 0, then the owner has released all buffers and he is no longer owner of the queue. Otherwise we have a new owner. */ if (res == 0) diff --git a/drivers/media/v4l2-core/v4l2-ioctl.c b/drivers/media/v4l2-core/v4l2-ioctl.c index aaf83e254272..9791e2882382 100644 --- a/drivers/media/v4l2-core/v4l2-ioctl.c +++ b/drivers/media/v4l2-core/v4l2-ioctl.c @@ -1973,9 +1973,6 @@ static int v4l_reqbufs(const struct v4l2_ioctl_ops *ops, if (ret) return ret; - - CLEAR_AFTER_FIELD(p, capabilities); - return ops->vidioc_reqbufs(file, fh, p); } @@ -2015,7 +2012,7 @@ static int v4l_create_bufs(const struct v4l2_ioctl_ops *ops, if (ret) return ret; - CLEAR_AFTER_FIELD(create, capabilities); + CLEAR_AFTER_FIELD(create, flags); v4l_sanitize_format(&create->format); diff --git a/include/uapi/linux/videodev2.h b/include/uapi/linux/videodev2.h index 72efc1c544cd..169a8cf345ed 100644 --- a/include/uapi/linux/videodev2.h +++ b/include/uapi/linux/videodev2.h @@ -938,7 +938,10 @@ struct v4l2_requestbuffers { __u32 type; /* enum v4l2_buf_type */ __u32 memory; /* enum v4l2_memory */ __u32 capabilities; - __u32 reserved[1]; + union { + __u32 flags; + __u32 reserved[1]; + }; }; /* capabilities for struct v4l2_requestbuffers and v4l2_create_buffers */ @@ -2445,7 +2448,8 @@ struct v4l2_create_buffers { __u32 memory; struct v4l2_format format; __u32 capabilities; - __u32 reserved[7]; + __u32 flags; + __u32 reserved[6]; }; /*
This patch lets user-space to request a non-consistent 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. = REQBUFS We use one bit of a ->reserved[1] member of struct v4l2_requestbuffers, which is now renamed to ->flags. Unlike v4l2_create_buffers, struct v4l2_requestbuffers does not have enough reserved room. Therefore for backward compatibility ->reserved and ->flags were put into anonymous union. Change-Id: I0eaab3428de499ce1bce6fc6b26c5ca5ff405882 Signed-off-by: Sergey Senozhatsky <senozhatsky@chromium.org> --- .../media/uapi/v4l/vidioc-create-bufs.rst | 9 +++++++- .../media/uapi/v4l/vidioc-reqbufs.rst | 15 ++++++++++--- .../media/common/videobuf2/videobuf2-v4l2.c | 21 ++++++++++++++++--- drivers/media/v4l2-core/v4l2-ioctl.c | 5 +---- include/uapi/linux/videodev2.h | 8 +++++-- 5 files changed, 45 insertions(+), 13 deletions(-)