Hello everyone, This patchset adds support for DMABUF [2] importing to V4L2 stack. The support for DMABUF exporting was moved to separate patchset due to dependency on patches for DMA mapping redesign by Marek Szyprowski [4].
v6: - fixed missing entry in v4l2_memory_names - fixed a bug occuring after get_user_pages failure - fixed a bug caused by using invalid vma for get_user_pages - prepare/finish no longer call dma_sync for dmabuf buffers
v5: - removed change of importer/exporter behaviour - fixes vb2_dc_pages_to_sgt basing on Laurent's hints - changed pin/unpin words to lock/unlock in Doc
v4: - rebased on mainline 3.4-rc2 - included missing importing support for s5p-fimc and s5p-tv - added patch for changing map/unmap for importers - fixes to Documentation part - coding style fixes - pairing {map/unmap}_dmabuf in vb2-core - fixing variable types and semantic of arguments in videobufb2-dma-contig.c
v3: - rebased on mainline 3.4-rc1 - split 'code refactor' patch to multiple smaller patches - squashed fixes to Sumit's patches - patchset is no longer dependant on 'DMA mapping redesign' - separated path for handling IO and non-IO mappings - add documentation for DMABUF importing to V4L - removed all DMABUF exporter related code - removed usage of dma_get_pages extension
v2: - extended VIDIOC_EXPBUF argument from integer memoffset to struct v4l2_exportbuffer - added patch that breaks DMABUF spec on (un)map_atachment callcacks but allows to work with existing implementation of DMABUF prime in DRM - all dma-contig code refactoring patches were squashed - bugfixes
v1: List of changes since [1]. - support for DMA api extension dma_get_pages, the function is used to retrieve pages used to create DMA mapping. - small fixes/code cleanup to videobuf2 - added prepare and finish callbacks to vb2 allocators, it is used keep consistency between dma-cpu acess to the memory (by Marek Szyprowski) - support for exporting of DMABUF buffer in V4L2 and Videobuf2, originated from [3]. - support for dma-buf exporting in vb2-dma-contig allocator - support for DMABUF for s5p-tv and s5p-fimc (capture interface) drivers, originated from [3] - changed handling for userptr buffers (by Marek Szyprowski, Andrzej Pietrasiewicz) - let mmap method to use dma_mmap_writecombine call (by Marek Szyprowski)
[1] http://thread.gmane.org/gmane.linux.drivers.video-input-infrastructure/42966... [2] https://lkml.org/lkml/2011/12/26/29 [3] http://thread.gmane.org/gmane.linux.drivers.video-input-infrastructure/36354... [4] http://thread.gmane.org/gmane.linux.kernel.cross-arch/12819
Laurent Pinchart (2): v4l: vb2-dma-contig: Shorten vb2_dma_contig prefix to vb2_dc v4l: vb2-dma-contig: Reorder functions
Marek Szyprowski (2): v4l: vb2: add prepare/finish callbacks to allocators v4l: vb2-dma-contig: add prepare/finish to dma-contig allocator
Sumit Semwal (4): v4l: Add DMABUF as a memory type v4l: vb2: add support for shared buffer (dma_buf) v4l: vb: remove warnings about MEMORY_DMABUF v4l: vb2-dma-contig: add support for dma_buf importing
Tomasz Stanislawski (5): Documentation: media: description of DMABUF importing in V4L2 v4l: vb2-dma-contig: Remove unneeded allocation context structure v4l: vb2-dma-contig: add support for scatterlist in userptr mode v4l: s5p-tv: mixer: support for dmabuf importing v4l: s5p-fimc: support for dmabuf importing
Documentation/DocBook/media/v4l/compat.xml | 4 + Documentation/DocBook/media/v4l/io.xml | 179 +++++++ .../DocBook/media/v4l/vidioc-create-bufs.xml | 1 + Documentation/DocBook/media/v4l/vidioc-qbuf.xml | 15 + Documentation/DocBook/media/v4l/vidioc-reqbufs.xml | 45 +- drivers/media/video/s5p-fimc/Kconfig | 1 + drivers/media/video/s5p-fimc/fimc-capture.c | 2 +- drivers/media/video/s5p-tv/Kconfig | 1 + drivers/media/video/s5p-tv/mixer_video.c | 2 +- drivers/media/video/v4l2-ioctl.c | 1 + drivers/media/video/videobuf-core.c | 4 + drivers/media/video/videobuf2-core.c | 207 +++++++- drivers/media/video/videobuf2-dma-contig.c | 520 +++++++++++++++++--- include/linux/videodev2.h | 7 + include/media/videobuf2-core.h | 34 ++ 15 files changed, 924 insertions(+), 99 deletions(-)
From: Sumit Semwal sumit.semwal@ti.com
Adds DMABUF memory type to v4l framework. Also adds the related file descriptor in v4l2_plane and v4l2_buffer.
Signed-off-by: Tomasz Stanislawski t.stanislaws@samsung.com [original work in the PoC for buffer sharing] Signed-off-by: Sumit Semwal sumit.semwal@ti.com Signed-off-by: Sumit Semwal sumit.semwal@linaro.org Acked-by: Laurent Pinchart laurent.pinchart@ideasonboard.com --- drivers/media/video/v4l2-ioctl.c | 1 + include/linux/videodev2.h | 7 +++++++ 2 files changed, 8 insertions(+)
diff --git a/drivers/media/video/v4l2-ioctl.c b/drivers/media/video/v4l2-ioctl.c index 91be4e8..31fc2ad 100644 --- a/drivers/media/video/v4l2-ioctl.c +++ b/drivers/media/video/v4l2-ioctl.c @@ -175,6 +175,7 @@ static const char *v4l2_memory_names[] = { [V4L2_MEMORY_MMAP] = "mmap", [V4L2_MEMORY_USERPTR] = "userptr", [V4L2_MEMORY_OVERLAY] = "overlay", + [V4L2_MEMORY_DMABUF] = "dmabuf", };
#define prt_names(a, arr) ((((a) >= 0) && ((a) < ARRAY_SIZE(arr))) ? \ diff --git a/include/linux/videodev2.h b/include/linux/videodev2.h index 370d111..51b20f4 100644 --- a/include/linux/videodev2.h +++ b/include/linux/videodev2.h @@ -185,6 +185,7 @@ enum v4l2_memory { V4L2_MEMORY_MMAP = 1, V4L2_MEMORY_USERPTR = 2, V4L2_MEMORY_OVERLAY = 3, + V4L2_MEMORY_DMABUF = 4, };
/* see also http://vektor.theorem.ca/graphics/ycbcr/ */ @@ -591,6 +592,8 @@ struct v4l2_requestbuffers { * should be passed to mmap() called on the video node) * @userptr: when memory is V4L2_MEMORY_USERPTR, a userspace pointer * pointing to this plane + * @fd: when memory is V4L2_MEMORY_DMABUF, a userspace file + * descriptor associated with this plane * @data_offset: offset in the plane to the start of data; usually 0, * unless there is a header in front of the data * @@ -605,6 +608,7 @@ struct v4l2_plane { union { __u32 mem_offset; unsigned long userptr; + int fd; } m; __u32 data_offset; __u32 reserved[11]; @@ -629,6 +633,8 @@ struct v4l2_plane { * (or a "cookie" that should be passed to mmap() as offset) * @userptr: for non-multiplanar buffers with memory == V4L2_MEMORY_USERPTR; * a userspace pointer pointing to this buffer + * @fd: for non-multiplanar buffers with memory == V4L2_MEMORY_DMABUF; + * a userspace file descriptor associated with this buffer * @planes: for multiplanar buffers; userspace pointer to the array of plane * info structs for this buffer * @length: size in bytes of the buffer (NOT its payload) for single-plane @@ -655,6 +661,7 @@ struct v4l2_buffer { __u32 offset; unsigned long userptr; struct v4l2_plane *planes; + int fd; } m; __u32 length; __u32 input;
Hi Tomasz,
Thanks for the patch.
On Wednesday 23 May 2012 14:10:15 Tomasz Stanislawski wrote:
From: Sumit Semwal sumit.semwal@ti.com
Adds DMABUF memory type to v4l framework. Also adds the related file descriptor in v4l2_plane and v4l2_buffer.
Sorry not to have caught this earlier, but haven't you forgotten to add support for V4L2_MEMORY_DMABUF to v4l2-compat-ioctl32.c ?
Signed-off-by: Tomasz Stanislawski t.stanislaws@samsung.com [original work in the PoC for buffer sharing] Signed-off-by: Sumit Semwal sumit.semwal@ti.com Signed-off-by: Sumit Semwal sumit.semwal@linaro.org Acked-by: Laurent Pinchart laurent.pinchart@ideasonboard.com
drivers/media/video/v4l2-ioctl.c | 1 + include/linux/videodev2.h | 7 +++++++ 2 files changed, 8 insertions(+)
diff --git a/drivers/media/video/v4l2-ioctl.c b/drivers/media/video/v4l2-ioctl.c index 91be4e8..31fc2ad 100644 --- a/drivers/media/video/v4l2-ioctl.c +++ b/drivers/media/video/v4l2-ioctl.c @@ -175,6 +175,7 @@ static const char *v4l2_memory_names[] = { [V4L2_MEMORY_MMAP] = "mmap", [V4L2_MEMORY_USERPTR] = "userptr", [V4L2_MEMORY_OVERLAY] = "overlay",
- [V4L2_MEMORY_DMABUF] = "dmabuf",
};
#define prt_names(a, arr) ((((a) >= 0) && ((a) < ARRAY_SIZE(arr))) ? \ diff --git a/include/linux/videodev2.h b/include/linux/videodev2.h index 370d111..51b20f4 100644 --- a/include/linux/videodev2.h +++ b/include/linux/videodev2.h @@ -185,6 +185,7 @@ enum v4l2_memory { V4L2_MEMORY_MMAP = 1, V4L2_MEMORY_USERPTR = 2, V4L2_MEMORY_OVERLAY = 3,
- V4L2_MEMORY_DMABUF = 4,
};
/* see also http://vektor.theorem.ca/graphics/ycbcr/ */ @@ -591,6 +592,8 @@ struct v4l2_requestbuffers {
should be passed to mmap() called on the video node)
- @userptr: when memory is V4L2_MEMORY_USERPTR, a userspace pointer
pointing to this plane
- @fd: when memory is V4L2_MEMORY_DMABUF, a userspace file
descriptor associated with this plane
- @data_offset: offset in the plane to the start of data; usually 0,
unless there is a header in front of the data
@@ -605,6 +608,7 @@ struct v4l2_plane { union { __u32 mem_offset; unsigned long userptr;
} m; __u32 data_offset; __u32 reserved[11];int fd;
@@ -629,6 +633,8 @@ struct v4l2_plane {
(or a "cookie" that should be passed to mmap() as offset)
- @userptr: for non-multiplanar buffers with memory ==
V4L2_MEMORY_USERPTR; * a userspace pointer pointing to this buffer
- @fd: for non-multiplanar buffers with memory ==
V4L2_MEMORY_DMABUF;
a userspace file descriptor associated with this buffer
- @planes: for multiplanar buffers; userspace pointer to the array of
plane * info structs for this buffer
- @length: size in bytes of the buffer (NOT its payload) for single-
plane
@@ -655,6 +661,7 @@ struct v4l2_buffer { __u32 offset; unsigned long userptr; struct v4l2_plane *planes;
} m; __u32 length; __u32 input;int fd;
This patch adds description and usage examples for importing DMABUF file descriptor in V4L2.
Signed-off-by: Tomasz Stanislawski t.stanislaws@samsung.com Signed-off-by: Kyungmin Park kyungmin.park@samsung.com CC: linux-doc@vger.kernel.org --- Documentation/DocBook/media/v4l/compat.xml | 4 + Documentation/DocBook/media/v4l/io.xml | 179 ++++++++++++++++++++ .../DocBook/media/v4l/vidioc-create-bufs.xml | 1 + Documentation/DocBook/media/v4l/vidioc-qbuf.xml | 15 ++ Documentation/DocBook/media/v4l/vidioc-reqbufs.xml | 45 ++--- 5 files changed, 223 insertions(+), 21 deletions(-)
diff --git a/Documentation/DocBook/media/v4l/compat.xml b/Documentation/DocBook/media/v4l/compat.xml index ea42ef8..07a311f 100644 --- a/Documentation/DocBook/media/v4l/compat.xml +++ b/Documentation/DocBook/media/v4l/compat.xml @@ -2587,6 +2587,10 @@ ioctls.</para> <para><link linkend="v4l2-auto-focus-area"><constant> V4L2_CID_AUTO_FOCUS_AREA</constant></link> control.</para> </listitem> + <listitem> + <para>Importing DMABUF file descriptors as a new IO method described + in <xref linkend="dmabuf" />.</para> + </listitem> </itemizedlist> </section>
diff --git a/Documentation/DocBook/media/v4l/io.xml b/Documentation/DocBook/media/v4l/io.xml index fd6aca2..521f699 100644 --- a/Documentation/DocBook/media/v4l/io.xml +++ b/Documentation/DocBook/media/v4l/io.xml @@ -472,6 +472,162 @@ rest should be evident.</para> </footnote></para> </section>
+ <section id="dmabuf"> + <title>Streaming I/O (DMA buffer importing)</title> + + <note> + <title>Experimental</title> + <para>This is an <link linkend="experimental"> experimental </link> + interface and may change in the future.</para> + </note> + +<para>The DMABUF framework provides a generic mean for sharing buffers between + multiple devices. Device drivers that support DMABUF can export a DMA buffer +to userspace as a file descriptor (known as the exporter role), import a DMA +buffer from userspace using a file descriptor previously exported for a +different or the same device (known as the importer role), or both. This +section describes the DMABUF importer role API in V4L2.</para> + +<para>Input and output devices support the streaming I/O method when the +<constant>V4L2_CAP_STREAMING</constant> flag in the +<structfield>capabilities</structfield> field of &v4l2-capability; returned by +the &VIDIOC-QUERYCAP; ioctl is set. Whether importing DMA buffers through +DMABUF file descriptors is supported is determined by calling the +&VIDIOC-REQBUFS; ioctl with the memory type set to +<constant>V4L2_MEMORY_DMABUF</constant>.</para> + + <para>This I/O method is dedicated for sharing DMA buffers between V4L and +other APIs. Buffers (planes) are allocated by a driver on behalf of the +application, and exported to the application as file descriptors using an API +specific to the allocator driver. Only those file descriptor are exchanged, +these files and meta-information are passed in &v4l2-buffer; (or in +&v4l2-plane; in the multi-planar API case). The driver must be switched into +DMABUF I/O mode by calling the &VIDIOC-REQBUFS; with the desired buffer type. +No buffers (planes) are allocated beforehand, consequently they are not indexed +and cannot be queried like mapped buffers with the +<constant>VIDIOC_QUERYBUF</constant> ioctl.</para> + + <example> + <title>Initiating streaming I/O with DMABUF file descriptors</title> + + <programlisting> +&v4l2-requestbuffers; reqbuf; + +memset (&reqbuf, 0, sizeof (reqbuf)); +reqbuf.type = V4L2_BUF_TYPE_VIDEO_CAPTURE; +reqbuf.memory = V4L2_MEMORY_DMABUF; + +if (ioctl (fd, &VIDIOC-REQBUFS;, &reqbuf) == -1) { + if (errno == EINVAL) + printf ("Video capturing or DMABUF streaming is not supported\n"); + else + perror ("VIDIOC_REQBUFS"); + + exit (EXIT_FAILURE); +} + </programlisting> + </example> + + <para>Buffer (plane) file is passed on the fly with the &VIDIOC-QBUF; +ioctl. In case of multiplanar buffers, every plane can be associated with a +different DMABUF descriptor.Although buffers are commonly cycled, applications +can pass different DMABUF descriptor at each <constant>VIDIOC_QBUF</constant> +call.</para> + + <example> + <title>Queueing DMABUF using single plane API</title> + + <programlisting> +int buffer_queue(int v4lfd, int index, int dmafd) +{ + &v4l2-buffer; buf; + + memset(&buf, 0, sizeof buf); + buf.type = V4L2_BUF_TYPE_VIDEO_CAPTURE; + buf.memory = V4L2_MEMORY_DMABUF; + buf.index = index; + buf.m.fd = dmafd; + + if (ioctl (v4lfd, &VIDIOC-QBUF;, &buf) == -1) { + perror ("VIDIOC_QBUF"); + return -1; + } + + return 0; +} + </programlisting> + </example> + + <example> + <title>Queueing DMABUF using multi plane API</title> + + <programlisting> +int buffer_queue_mp(int v4lfd, int index, int dmafd[], int n_planes) +{ + &v4l2-buffer; buf; + &v4l2-plane; planes[VIDEO_MAX_PLANES]; + int i; + + memset(&buf, 0, sizeof buf); + buf.type = V4L2_BUF_TYPE_VIDEO_CAPTURE_MPLANE; + buf.memory = V4L2_MEMORY_DMABUF; + buf.index = index; + buf.m.planes = planes; + buf.length = n_planes; + + memset(&planes, 0, sizeof planes); + + for (i = 0; i < n_planes; ++i) + buf.m.planes[i].m.fd = dmafd[i]; + + if (ioctl (v4lfd, &VIDIOC-QBUF;, &buf) == -1) { + perror ("VIDIOC_QBUF"); + return -1; + } + + return 0; +} + </programlisting> + </example> + + <para>Filled or displayed buffers are dequeued with the +&VIDIOC-DQBUF; ioctl. The driver can unlock the buffer at any +time between the completion of the DMA and this ioctl. The memory is +also unlocked when &VIDIOC-STREAMOFF; is called, &VIDIOC-REQBUFS;, or +when the device is closed.</para> + + <para>For capturing applications it is customary to enqueue a +number of empty buffers, to start capturing and enter the read loop. +Here the application waits until a filled buffer can be dequeued, and +re-enqueues the buffer when the data is no longer needed. Output +applications fill and enqueue buffers, when enough buffers are stacked +up output is started. In the write loop, when the application +runs out of free buffers it must wait until an empty buffer can be +dequeued and reused. Two methods exist to suspend execution of the +application until one or more buffers can be dequeued. By default +<constant>VIDIOC_DQBUF</constant> blocks when no buffer is in the +outgoing queue. When the <constant>O_NONBLOCK</constant> flag was +given to the &func-open; function, <constant>VIDIOC_DQBUF</constant> +returns immediately with an &EAGAIN; when no buffer is available. The +&func-select; or &func-poll; function are always available.</para> + + <para>To start and stop capturing or output applications call the +&VIDIOC-STREAMON; and &VIDIOC-STREAMOFF; ioctls. Note that +<constant>VIDIOC_STREAMOFF</constant> removes all buffers from both queues and +unlocks all buffers as a side effect. Since there is no notion of doing +anything "now" on a multitasking system, if an application needs to synchronize +with another event it should examine the &v4l2-buffer; +<structfield>timestamp</structfield> of captured buffers, or set the field +before enqueuing buffers for output.</para> + + <para>Drivers implementing DMABUF importing I/O must support the +<constant>VIDIOC_REQBUFS</constant>, <constant>VIDIOC_QBUF</constant>, +<constant>VIDIOC_DQBUF</constant>, <constant>VIDIOC_STREAMON</constant> and +<constant>VIDIOC_STREAMOFF</constant> ioctl, the <function>select()</function> +and <function>poll()</function> function.</para> + + </section> + <section id="async"> <title>Asynchronous I/O</title>
@@ -673,6 +829,14 @@ memory, set by the application. See <xref linkend="userp" /> for details. <structname>v4l2_buffer</structname> structure.</entry> </row> <row> + <entry></entry> + <entry>int</entry> + <entry><structfield>fd</structfield></entry> + <entry>For the single-plane API and when +<structfield>memory</structfield> is <constant>V4L2_MEMORY_DMABUF</constant> this +is the file descriptor associated with a DMABUF buffer.</entry> + </row> + <row> <entry>__u32</entry> <entry><structfield>length</structfield></entry> <entry></entry> @@ -748,6 +912,15 @@ should set this to 0.</entry> </entry> </row> <row> + <entry></entry> + <entry>int</entry> + <entry><structfield>fd</structfield></entry> + <entry>When the memory type in the containing &v4l2-buffer; is + <constant>V4L2_MEMORY_DMABUF</constant>, this is a file + descriptor associated with a DMABUF buffer, similar to the + <structfield>fd</structfield> field in &v4l2-buffer;.</entry> + </row> + <row> <entry>__u32</entry> <entry><structfield>data_offset</structfield></entry> <entry></entry> @@ -982,6 +1155,12 @@ pointer</link> I/O.</entry> <entry>3</entry> <entry>[to do]</entry> </row> + <row> + <entry><constant>V4L2_MEMORY_DMABUF</constant></entry> + <entry>2</entry> + <entry>The buffer is used for <link linkend="dmabuf">DMA shared +buffer</link> I/O.</entry> + </row> </tbody> </tgroup> </table> diff --git a/Documentation/DocBook/media/v4l/vidioc-create-bufs.xml b/Documentation/DocBook/media/v4l/vidioc-create-bufs.xml index 765549f..fee66ac 100644 --- a/Documentation/DocBook/media/v4l/vidioc-create-bufs.xml +++ b/Documentation/DocBook/media/v4l/vidioc-create-bufs.xml @@ -104,6 +104,7 @@ information.</para> <entry><structfield>memory</structfield></entry> <entry>Applications set this field to <constant>V4L2_MEMORY_MMAP</constant> or +<constant>V4L2_MEMORY_DMABUF</constant> or <constant>V4L2_MEMORY_USERPTR</constant>. See <xref linkend="v4l2-memory" /></entry> </row> diff --git a/Documentation/DocBook/media/v4l/vidioc-qbuf.xml b/Documentation/DocBook/media/v4l/vidioc-qbuf.xml index 9caa49a..cb5f5ff 100644 --- a/Documentation/DocBook/media/v4l/vidioc-qbuf.xml +++ b/Documentation/DocBook/media/v4l/vidioc-qbuf.xml @@ -112,6 +112,21 @@ they cannot be swapped out to disk. Buffers remain locked until dequeued, until the &VIDIOC-STREAMOFF; or &VIDIOC-REQBUFS; ioctl is called, or until the device is closed.</para>
+ <para>To enqueue a <link linkend="dmabuf">DMABUF</link> buffer applications +set the <structfield>memory</structfield> field to +<constant>V4L2_MEMORY_DMABUF</constant> and the <structfield>m.fd</structfield> +to a file descriptor associated with a DMABUF buffer. When the multi-planar API is +used and <structfield>m.fd</structfield> of the passed array of &v4l2-plane; +have to be used instead. When <constant>VIDIOC_QBUF</constant> is called with a +pointer to this structure the driver sets the +<constant>V4L2_BUF_FLAG_QUEUED</constant> flag and clears the +<constant>V4L2_BUF_FLAG_MAPPED</constant> and +<constant>V4L2_BUF_FLAG_DONE</constant> flags in the +<structfield>flags</structfield> field, or it returns an error code. This +ioctl locks the buffer. Buffers remain locked until dequeued, +until the &VIDIOC-STREAMOFF; or &VIDIOC-REQBUFS; ioctl is called, or until the +device is closed.</para> + <para>Applications call the <constant>VIDIOC_DQBUF</constant> ioctl to dequeue a filled (capturing) or displayed (output) buffer from the driver's outgoing queue. They just set the diff --git a/Documentation/DocBook/media/v4l/vidioc-reqbufs.xml b/Documentation/DocBook/media/v4l/vidioc-reqbufs.xml index d7c9505..13381ea 100644 --- a/Documentation/DocBook/media/v4l/vidioc-reqbufs.xml +++ b/Documentation/DocBook/media/v4l/vidioc-reqbufs.xml @@ -48,28 +48,30 @@ <refsect1> <title>Description</title>
- <para>This ioctl is used to initiate <link linkend="mmap">memory -mapped</link> or <link linkend="userp">user pointer</link> -I/O. Memory mapped buffers are located in device memory and must be -allocated with this ioctl before they can be mapped into the -application's address space. User buffers are allocated by -applications themselves, and this ioctl is merely used to switch the -driver into user pointer I/O mode and to setup some internal structures.</para> +<para>This ioctl is used to initiate <link linkend="mmap">memory mapped</link>, +<link linkend="userp">user pointer</link> or <link +linkend="dmabuf">DMABUF</link> based I/O. Memory mapped buffers are located in +device memory and must be allocated with this ioctl before they can be mapped +into the application's address space. User buffers are allocated by +applications themselves, and this ioctl is merely used to switch the driver +into user pointer I/O mode and to setup some internal structures. +Similarly, DMABUF buffers are allocated by applications through a device +driver, and this ioctl only configures the driver into DMABUF I/O mode without +performing any direct allocation.</para>
- <para>To allocate device buffers applications initialize all -fields of the <structname>v4l2_requestbuffers</structname> structure. -They set the <structfield>type</structfield> field to the respective -stream or buffer type, the <structfield>count</structfield> field to -the desired number of buffers, <structfield>memory</structfield> -must be set to the requested I/O method and the <structfield>reserved</structfield> array -must be zeroed. When the ioctl -is called with a pointer to this structure the driver will attempt to allocate -the requested number of buffers and it stores the actual number -allocated in the <structfield>count</structfield> field. It can be -smaller than the number requested, even zero, when the driver runs out -of free memory. A larger number is also possible when the driver requires -more buffers to function correctly. For example video output requires at least two buffers, -one displayed and one filled by the application.</para> + <para>To allocate device buffers applications initialize all fields of the +<structname>v4l2_requestbuffers</structname> structure. They set the +<structfield>type</structfield> field to the respective stream or buffer type, +the <structfield>count</structfield> field to the desired number of buffers, +<structfield>memory</structfield> must be set to the requested I/O method and +the <structfield>reserved</structfield> array must be zeroed. When the ioctl is +called with a pointer to this structure the driver will attempt to allocate the +requested number of buffers and it stores the actual number allocated in the +<structfield>count</structfield> field. It can be smaller than the number +requested, even zero, when the driver runs out of free memory. A larger number +is also possible when the driver requires more buffers to function correctly. +For example video output requires at least two buffers, one displayed and one +filled by the application.</para> <para>When the I/O method is not supported the ioctl returns an &EINVAL;.</para>
@@ -103,6 +105,7 @@ as the &v4l2-format; <structfield>type</structfield> field. See <xref <entry><structfield>memory</structfield></entry> <entry>Applications set this field to <constant>V4L2_MEMORY_MMAP</constant> or +<constant>V4L2_MEMORY_DMABUF</constant> or <constant>V4L2_MEMORY_USERPTR</constant>. See <xref linkend="v4l2-memory" />.</entry> </row>
Hi Tomasz,
Thanks for the patch.
On Wednesday 23 May 2012 14:10:16 Tomasz Stanislawski wrote:
This patch adds description and usage examples for importing DMABUF file descriptor in V4L2.
Signed-off-by: Tomasz Stanislawski t.stanislaws@samsung.com Signed-off-by: Kyungmin Park kyungmin.park@samsung.com CC: linux-doc@vger.kernel.org
[snip]
@@ -103,6 +105,7 @@ as the &v4l2-format; <structfield>type</structfield> field. See <xref <entry><structfield>memory</structfield></entry> <entry>Applications set this field to <constant>V4L2_MEMORY_MMAP</constant> or +<constant>V4L2_MEMORY_DMABUF</constant> or <constant>V4L2_MEMORY_USERPTR</constant>. See <xref linkend="v4l2-memory" />.</entry> </row>
If you resubmit to fix the compat-ioctl issue in 01/13, could you please replace this with
<entry>Applications set this field to <constant>V4L2_MEMORY_MMAP</constant>, <constant>V4L2_MEMORY_DMABUF</constant> or <constant>V4L2_MEMORY_USERPTR</constant>. See <xref linkend="v4l2-memory"/>. </entry>
like in v5 ?
From: Sumit Semwal sumit.semwal@ti.com
This patch adds support for DMABUF memory type in videobuf2. It calls relevant APIs of dma_buf for v4l reqbuf / qbuf / dqbuf operations.
For this version, the support is for videobuf2 as a user of the shared buffer; so the allocation of the buffer is done outside of V4L2. [A sample allocator of dma-buf shared buffer is given at [1]]
[1]: Rob Clark's DRM: https://github.com/robclark/kernel-omap4/commits/drmplane-dmabuf
Signed-off-by: Tomasz Stanislawski t.stanislaws@samsung.com [original work in the PoC for buffer sharing] Signed-off-by: Sumit Semwal sumit.semwal@ti.com Signed-off-by: Sumit Semwal sumit.semwal@linaro.org Acked-by: Laurent Pinchart laurent.pinchart@ideasonboard.com --- drivers/media/video/videobuf2-core.c | 196 +++++++++++++++++++++++++++++++++- include/media/videobuf2-core.h | 27 +++++ 2 files changed, 219 insertions(+), 4 deletions(-)
diff --git a/drivers/media/video/videobuf2-core.c b/drivers/media/video/videobuf2-core.c index 9d4e9ed..f43cfa4 100644 --- a/drivers/media/video/videobuf2-core.c +++ b/drivers/media/video/videobuf2-core.c @@ -109,6 +109,36 @@ static void __vb2_buf_userptr_put(struct vb2_buffer *vb) }
/** + * __vb2_plane_dmabuf_put() - release memory associated with + * a DMABUF shared plane + */ +static void __vb2_plane_dmabuf_put(struct vb2_queue *q, struct vb2_plane *p) +{ + if (!p->mem_priv) + return; + + if (p->dbuf_mapped) + call_memop(q, unmap_dmabuf, p->mem_priv); + + call_memop(q, detach_dmabuf, p->mem_priv); + dma_buf_put(p->dbuf); + memset(p, 0, sizeof *p); +} + +/** + * __vb2_buf_dmabuf_put() - release memory associated with + * a DMABUF shared buffer + */ +static void __vb2_buf_dmabuf_put(struct vb2_buffer *vb) +{ + struct vb2_queue *q = vb->vb2_queue; + unsigned int plane; + + for (plane = 0; plane < vb->num_planes; ++plane) + __vb2_plane_dmabuf_put(q, &vb->planes[plane]); +} + +/** * __setup_offsets() - setup unique offsets ("cookies") for every plane in * every buffer on the queue */ @@ -230,6 +260,8 @@ static void __vb2_free_mem(struct vb2_queue *q, unsigned int buffers) /* Free MMAP buffers or release USERPTR buffers */ if (q->memory == V4L2_MEMORY_MMAP) __vb2_buf_mem_free(vb); + else if (q->memory == V4L2_MEMORY_DMABUF) + __vb2_buf_dmabuf_put(vb); else __vb2_buf_userptr_put(vb); } @@ -352,6 +384,12 @@ static int __fill_v4l2_buffer(struct vb2_buffer *vb, struct v4l2_buffer *b) */ memcpy(b->m.planes, vb->v4l2_planes, b->length * sizeof(struct v4l2_plane)); + + if (q->memory == V4L2_MEMORY_DMABUF) { + unsigned int plane; + for (plane = 0; plane < vb->num_planes; ++plane) + b->m.planes[plane].m.fd = 0; + } } else { /* * We use length and offset in v4l2_planes array even for @@ -363,6 +401,8 @@ static int __fill_v4l2_buffer(struct vb2_buffer *vb, struct v4l2_buffer *b) b->m.offset = vb->v4l2_planes[0].m.mem_offset; else if (q->memory == V4L2_MEMORY_USERPTR) b->m.userptr = vb->v4l2_planes[0].m.userptr; + else if (q->memory == V4L2_MEMORY_DMABUF) + b->m.fd = 0; }
/* @@ -454,6 +494,20 @@ static int __verify_mmap_ops(struct vb2_queue *q) }
/** + * __verify_dmabuf_ops() - verify that all memory operations required for + * DMABUF queue type have been provided + */ +static int __verify_dmabuf_ops(struct vb2_queue *q) +{ + if (!(q->io_modes & VB2_DMABUF) || !q->mem_ops->attach_dmabuf || + !q->mem_ops->detach_dmabuf || !q->mem_ops->map_dmabuf || + !q->mem_ops->unmap_dmabuf) + return -EINVAL; + + return 0; +} + +/** * vb2_reqbufs() - Initiate streaming * @q: videobuf2 queue * @req: struct passed from userspace to vidioc_reqbufs handler in driver @@ -486,8 +540,9 @@ int vb2_reqbufs(struct vb2_queue *q, struct v4l2_requestbuffers *req) return -EBUSY; }
- if (req->memory != V4L2_MEMORY_MMAP - && req->memory != V4L2_MEMORY_USERPTR) { + if (req->memory != V4L2_MEMORY_MMAP && + req->memory != V4L2_MEMORY_DMABUF && + req->memory != V4L2_MEMORY_USERPTR) { dprintk(1, "reqbufs: unsupported memory type\n"); return -EINVAL; } @@ -516,6 +571,11 @@ int vb2_reqbufs(struct vb2_queue *q, struct v4l2_requestbuffers *req) return -EINVAL; }
+ if (req->memory == V4L2_MEMORY_DMABUF && __verify_dmabuf_ops(q)) { + dprintk(1, "reqbufs: DMABUF for current setup unsupported\n"); + return -EINVAL; + } + if (req->count == 0 || q->num_buffers != 0 || q->memory != req->memory) { /* * We already have buffers allocated, so first check if they @@ -622,8 +682,9 @@ int vb2_create_bufs(struct vb2_queue *q, struct v4l2_create_buffers *create) return -EBUSY; }
- if (create->memory != V4L2_MEMORY_MMAP - && create->memory != V4L2_MEMORY_USERPTR) { + if (create->memory != V4L2_MEMORY_MMAP && + create->memory != V4L2_MEMORY_USERPTR && + create->memory != V4L2_MEMORY_DMABUF) { dprintk(1, "%s(): unsupported memory type\n", __func__); return -EINVAL; } @@ -647,6 +708,11 @@ int vb2_create_bufs(struct vb2_queue *q, struct v4l2_create_buffers *create) return -EINVAL; }
+ if (create->memory == V4L2_MEMORY_DMABUF && __verify_dmabuf_ops(q)) { + dprintk(1, "%s(): DMABUF for current setup unsupported\n", __func__); + return -EINVAL; + } + if (q->num_buffers == VIDEO_MAX_FRAME) { dprintk(1, "%s(): maximum number of buffers already allocated\n", __func__); @@ -842,6 +908,14 @@ static int __fill_vb2_buffer(struct vb2_buffer *vb, const struct v4l2_buffer *b, b->m.planes[plane].length; } } + if (b->memory == V4L2_MEMORY_DMABUF) { + for (plane = 0; plane < vb->num_planes; ++plane) { + v4l2_planes[plane].bytesused = + b->m.planes[plane].bytesused; + v4l2_planes[plane].m.fd = + b->m.planes[plane].m.fd; + } + } } else { /* * Single-planar buffers do not use planes array, @@ -856,6 +930,10 @@ static int __fill_vb2_buffer(struct vb2_buffer *vb, const struct v4l2_buffer *b, v4l2_planes[0].m.userptr = b->m.userptr; v4l2_planes[0].length = b->length; } + + if (b->memory == V4L2_MEMORY_DMABUF) + v4l2_planes[0].m.fd = b->m.fd; + }
vb->v4l2_buf.field = b->field; @@ -960,6 +1038,100 @@ static int __qbuf_mmap(struct vb2_buffer *vb, const struct v4l2_buffer *b) }
/** + * __qbuf_dmabuf() - handle qbuf of a DMABUF buffer + */ +static int __qbuf_dmabuf(struct vb2_buffer *vb, const struct v4l2_buffer *b) +{ + struct v4l2_plane planes[VIDEO_MAX_PLANES]; + struct vb2_queue *q = vb->vb2_queue; + void *mem_priv; + unsigned int plane; + int ret; + int write = !V4L2_TYPE_IS_OUTPUT(q->type); + + /* Verify and copy relevant information provided by the userspace */ + ret = __fill_vb2_buffer(vb, b, planes); + if (ret) + return ret; + + for (plane = 0; plane < vb->num_planes; ++plane) { + struct dma_buf *dbuf = dma_buf_get(planes[plane].m.fd); + + if (IS_ERR_OR_NULL(dbuf)) { + dprintk(1, "qbuf: invalid dmabuf fd for " + "plane %d\n", plane); + ret = -EINVAL; + goto err; + } + + /* Skip the plane if already verified */ + if (dbuf == vb->planes[plane].dbuf) { + planes[plane].length = dbuf->size; + dma_buf_put(dbuf); + continue; + } + + dprintk(3, "qbuf: buffer description for plane %d changed, " + "reattaching dma buf\n", plane); + + /* Release previously acquired memory if present */ + __vb2_plane_dmabuf_put(q, &vb->planes[plane]); + + /* Acquire each plane's memory */ + mem_priv = call_memop(q, attach_dmabuf, q->alloc_ctx[plane], + dbuf, q->plane_sizes[plane], write); + if (IS_ERR(mem_priv)) { + dprintk(1, "qbuf: failed acquiring dmabuf " + "memory for plane %d\n", plane); + ret = PTR_ERR(mem_priv); + goto err; + } + + planes[plane].length = dbuf->size; + vb->planes[plane].dbuf = dbuf; + vb->planes[plane].mem_priv = mem_priv; + } + + /* TODO: This pins the buffer(s) with dma_buf_map_attachment()).. but + * really we want to do this just before the DMA, not while queueing + * the buffer(s).. + */ + for (plane = 0; plane < vb->num_planes; ++plane) { + ret = call_memop(q, map_dmabuf, vb->planes[plane].mem_priv); + if (ret) { + dprintk(1, "qbuf: failed mapping dmabuf " + "memory for plane %d\n", plane); + goto err; + } + vb->planes[plane].dbuf_mapped = 1; + } + + /* + * Call driver-specific initialization on the newly acquired buffer, + * if provided. + */ + ret = call_qop(q, buf_init, vb); + if (ret) { + dprintk(1, "qbuf: buffer initialization failed\n"); + goto err; + } + + /* + * Now that everything is in order, copy relevant information + * provided by userspace. + */ + for (plane = 0; plane < vb->num_planes; ++plane) + vb->v4l2_planes[plane] = planes[plane]; + + return 0; +err: + /* In case of errors, release planes that were already acquired */ + __vb2_buf_dmabuf_put(vb); + + return ret; +} + +/** * __enqueue_in_driver() - enqueue a vb2_buffer in driver for processing */ static void __enqueue_in_driver(struct vb2_buffer *vb) @@ -983,6 +1155,9 @@ static int __buf_prepare(struct vb2_buffer *vb, const struct v4l2_buffer *b) case V4L2_MEMORY_USERPTR: ret = __qbuf_userptr(vb, b); break; + case V4L2_MEMORY_DMABUF: + ret = __qbuf_dmabuf(vb, b); + break; default: WARN(1, "Invalid queue type\n"); ret = -EINVAL; @@ -1338,6 +1513,19 @@ int vb2_dqbuf(struct vb2_queue *q, struct v4l2_buffer *b, bool nonblocking) return ret; }
+ /* TODO: this unpins the buffer(dma_buf_unmap_attachment()).. but + * really we want to do this just after DMA, not when the + * buffer is dequeued.. + */ + if (q->memory == V4L2_MEMORY_DMABUF) { + unsigned int i; + + for (i = 0; i < vb->num_planes; ++i) { + call_memop(q, unmap_dmabuf, vb->planes[i].mem_priv); + vb->planes[i].dbuf_mapped = 0; + } + } + switch (vb->state) { case VB2_BUF_STATE_DONE: dprintk(3, "dqbuf: Returning done buffer\n"); diff --git a/include/media/videobuf2-core.h b/include/media/videobuf2-core.h index a15d1f1..859bbaf 100644 --- a/include/media/videobuf2-core.h +++ b/include/media/videobuf2-core.h @@ -16,6 +16,7 @@ #include <linux/mutex.h> #include <linux/poll.h> #include <linux/videodev2.h> +#include <linux/dma-buf.h>
struct vb2_alloc_ctx; struct vb2_fileio_data; @@ -41,6 +42,20 @@ struct vb2_fileio_data; * argument to other ops in this structure * @put_userptr: inform the allocator that a USERPTR buffer will no longer * be used + * @attach_dmabuf: attach a shared struct dma_buf for a hardware operation; + * used for DMABUF memory types; alloc_ctx is the alloc context + * dbuf is the shared dma_buf; returns NULL on failure; + * allocator private per-buffer structure on success; + * this needs to be used for further accesses to the buffer + * @detach_dmabuf: inform the exporter of the buffer that the current DMABUF + * buffer is no longer used; the buf_priv argument is the + * allocator private per-buffer structure previously returned + * from the attach_dmabuf callback + * @map_dmabuf: request for access to the dmabuf from allocator; the allocator + * of dmabuf is informed that this driver is going to use the + * dmabuf + * @unmap_dmabuf: releases access control to the dmabuf - allocator is notified + * that this driver is done using the dmabuf for now * @vaddr: return a kernel virtual address to a given memory buffer * associated with the passed private structure or NULL if no * such mapping exists @@ -56,6 +71,8 @@ struct vb2_fileio_data; * Required ops for USERPTR types: get_userptr, put_userptr. * Required ops for MMAP types: alloc, put, num_users, mmap. * Required ops for read/write access types: alloc, put, num_users, vaddr + * Required ops for DMABUF types: attach_dmabuf, detach_dmabuf, map_dmabuf, + * unmap_dmabuf. */ struct vb2_mem_ops { void *(*alloc)(void *alloc_ctx, unsigned long size); @@ -65,6 +82,12 @@ struct vb2_mem_ops { unsigned long size, int write); void (*put_userptr)(void *buf_priv);
+ void *(*attach_dmabuf)(void *alloc_ctx, struct dma_buf *dbuf, + unsigned long size, int write); + void (*detach_dmabuf)(void *buf_priv); + int (*map_dmabuf)(void *buf_priv); + void (*unmap_dmabuf)(void *buf_priv); + void *(*vaddr)(void *buf_priv); void *(*cookie)(void *buf_priv);
@@ -75,6 +98,8 @@ struct vb2_mem_ops {
struct vb2_plane { void *mem_priv; + struct dma_buf *dbuf; + unsigned int dbuf_mapped; };
/** @@ -83,12 +108,14 @@ struct vb2_plane { * @VB2_USERPTR: driver supports USERPTR with streaming API * @VB2_READ: driver supports read() style access * @VB2_WRITE: driver supports write() style access + * @VB2_DMABUF: driver supports DMABUF with streaming API */ enum vb2_io_modes { VB2_MMAP = (1 << 0), VB2_USERPTR = (1 << 1), VB2_READ = (1 << 2), VB2_WRITE = (1 << 3), + VB2_DMABUF = (1 << 4), };
/**
From: Sumit Semwal sumit.semwal@ti.com
Adding DMABUF memory type causes videobuf to complain about not using it in some switch cases. This patch removes these warnings.
Signed-off-by: Sumit Semwal sumit.semwal@ti.com Acked-by: Laurent Pinchart laurent.pinchart@ideasonboard.com --- drivers/media/video/videobuf-core.c | 4 ++++ 1 file changed, 4 insertions(+)
diff --git a/drivers/media/video/videobuf-core.c b/drivers/media/video/videobuf-core.c index ffdf59c..3e3e55f 100644 --- a/drivers/media/video/videobuf-core.c +++ b/drivers/media/video/videobuf-core.c @@ -335,6 +335,9 @@ static void videobuf_status(struct videobuf_queue *q, struct v4l2_buffer *b, case V4L2_MEMORY_OVERLAY: b->m.offset = vb->boff; break; + case V4L2_MEMORY_DMABUF: + /* DMABUF is not handled in videobuf framework */ + break; }
b->flags = 0; @@ -411,6 +414,7 @@ int __videobuf_mmap_setup(struct videobuf_queue *q, break; case V4L2_MEMORY_USERPTR: case V4L2_MEMORY_OVERLAY: + case V4L2_MEMORY_DMABUF: /* nothing */ break; }
From: Laurent Pinchart laurent.pinchart@ideasonboard.com
Signed-off-by: Laurent Pinchart laurent.pinchart@ideasonboard.com --- drivers/media/video/videobuf2-dma-contig.c | 36 ++++++++++++++-------------- 1 file changed, 18 insertions(+), 18 deletions(-)
diff --git a/drivers/media/video/videobuf2-dma-contig.c b/drivers/media/video/videobuf2-dma-contig.c index 4b71326..a05784f 100644 --- a/drivers/media/video/videobuf2-dma-contig.c +++ b/drivers/media/video/videobuf2-dma-contig.c @@ -32,9 +32,9 @@ struct vb2_dc_buf { struct vb2_vmarea_handler handler; };
-static void vb2_dma_contig_put(void *buf_priv); +static void vb2_dc_put(void *buf_priv);
-static void *vb2_dma_contig_alloc(void *alloc_ctx, unsigned long size) +static void *vb2_dc_alloc(void *alloc_ctx, unsigned long size) { struct vb2_dc_conf *conf = alloc_ctx; struct vb2_dc_buf *buf; @@ -56,7 +56,7 @@ static void *vb2_dma_contig_alloc(void *alloc_ctx, unsigned long size) buf->size = size;
buf->handler.refcount = &buf->refcount; - buf->handler.put = vb2_dma_contig_put; + buf->handler.put = vb2_dc_put; buf->handler.arg = buf;
atomic_inc(&buf->refcount); @@ -64,7 +64,7 @@ static void *vb2_dma_contig_alloc(void *alloc_ctx, unsigned long size) return buf; }
-static void vb2_dma_contig_put(void *buf_priv) +static void vb2_dc_put(void *buf_priv) { struct vb2_dc_buf *buf = buf_priv;
@@ -75,14 +75,14 @@ static void vb2_dma_contig_put(void *buf_priv) } }
-static void *vb2_dma_contig_cookie(void *buf_priv) +static void *vb2_dc_cookie(void *buf_priv) { struct vb2_dc_buf *buf = buf_priv;
return &buf->dma_addr; }
-static void *vb2_dma_contig_vaddr(void *buf_priv) +static void *vb2_dc_vaddr(void *buf_priv) { struct vb2_dc_buf *buf = buf_priv; if (!buf) @@ -91,14 +91,14 @@ static void *vb2_dma_contig_vaddr(void *buf_priv) return buf->vaddr; }
-static unsigned int vb2_dma_contig_num_users(void *buf_priv) +static unsigned int vb2_dc_num_users(void *buf_priv) { struct vb2_dc_buf *buf = buf_priv;
return atomic_read(&buf->refcount); }
-static int vb2_dma_contig_mmap(void *buf_priv, struct vm_area_struct *vma) +static int vb2_dc_mmap(void *buf_priv, struct vm_area_struct *vma) { struct vb2_dc_buf *buf = buf_priv;
@@ -111,7 +111,7 @@ static int vb2_dma_contig_mmap(void *buf_priv, struct vm_area_struct *vma) &vb2_common_vm_ops, &buf->handler); }
-static void *vb2_dma_contig_get_userptr(void *alloc_ctx, unsigned long vaddr, +static void *vb2_dc_get_userptr(void *alloc_ctx, unsigned long vaddr, unsigned long size, int write) { struct vb2_dc_buf *buf; @@ -138,7 +138,7 @@ static void *vb2_dma_contig_get_userptr(void *alloc_ctx, unsigned long vaddr, return buf; }
-static void vb2_dma_contig_put_userptr(void *mem_priv) +static void vb2_dc_put_userptr(void *mem_priv) { struct vb2_dc_buf *buf = mem_priv;
@@ -150,14 +150,14 @@ static void vb2_dma_contig_put_userptr(void *mem_priv) }
const struct vb2_mem_ops vb2_dma_contig_memops = { - .alloc = vb2_dma_contig_alloc, - .put = vb2_dma_contig_put, - .cookie = vb2_dma_contig_cookie, - .vaddr = vb2_dma_contig_vaddr, - .mmap = vb2_dma_contig_mmap, - .get_userptr = vb2_dma_contig_get_userptr, - .put_userptr = vb2_dma_contig_put_userptr, - .num_users = vb2_dma_contig_num_users, + .alloc = vb2_dc_alloc, + .put = vb2_dc_put, + .cookie = vb2_dc_cookie, + .vaddr = vb2_dc_vaddr, + .mmap = vb2_dc_mmap, + .get_userptr = vb2_dc_get_userptr, + .put_userptr = vb2_dc_put_userptr, + .num_users = vb2_dc_num_users, }; EXPORT_SYMBOL_GPL(vb2_dma_contig_memops);
vb2-dma-contig returns a vb2_dc_conf structure instance as the vb2 allocation context. That structure only stores a pointer to the physical device. Remove it and use the device pointer directly as the allocation context.
Signed-off-by: Tomasz Stanislawski t.stanislaws@samsung.com Acked-by: Laurent Pinchart laurent.pinchart@ideasonboard.com --- drivers/media/video/videobuf2-dma-contig.c | 29 +++++++--------------------- 1 file changed, 7 insertions(+), 22 deletions(-)
diff --git a/drivers/media/video/videobuf2-dma-contig.c b/drivers/media/video/videobuf2-dma-contig.c index a05784f..a019cd1 100644 --- a/drivers/media/video/videobuf2-dma-contig.c +++ b/drivers/media/video/videobuf2-dma-contig.c @@ -18,12 +18,8 @@ #include <media/videobuf2-dma-contig.h> #include <media/videobuf2-memops.h>
-struct vb2_dc_conf { - struct device *dev; -}; - struct vb2_dc_buf { - struct vb2_dc_conf *conf; + struct device *dev; void *vaddr; dma_addr_t dma_addr; unsigned long size; @@ -36,23 +32,21 @@ static void vb2_dc_put(void *buf_priv);
static void *vb2_dc_alloc(void *alloc_ctx, unsigned long size) { - struct vb2_dc_conf *conf = alloc_ctx; + struct device *dev = alloc_ctx; struct vb2_dc_buf *buf;
buf = kzalloc(sizeof *buf, GFP_KERNEL); if (!buf) return ERR_PTR(-ENOMEM);
- buf->vaddr = dma_alloc_coherent(conf->dev, size, &buf->dma_addr, - GFP_KERNEL); + buf->vaddr = dma_alloc_coherent(dev, size, &buf->dma_addr, GFP_KERNEL); if (!buf->vaddr) { - dev_err(conf->dev, "dma_alloc_coherent of size %ld failed\n", - size); + dev_err(dev, "dma_alloc_coherent of size %ld failed\n", size); kfree(buf); return ERR_PTR(-ENOMEM); }
- buf->conf = conf; + buf->dev = dev; buf->size = size;
buf->handler.refcount = &buf->refcount; @@ -69,7 +63,7 @@ static void vb2_dc_put(void *buf_priv) struct vb2_dc_buf *buf = buf_priv;
if (atomic_dec_and_test(&buf->refcount)) { - dma_free_coherent(buf->conf->dev, buf->size, buf->vaddr, + dma_free_coherent(buf->dev, buf->size, buf->vaddr, buf->dma_addr); kfree(buf); } @@ -163,21 +157,12 @@ EXPORT_SYMBOL_GPL(vb2_dma_contig_memops);
void *vb2_dma_contig_init_ctx(struct device *dev) { - struct vb2_dc_conf *conf; - - conf = kzalloc(sizeof *conf, GFP_KERNEL); - if (!conf) - return ERR_PTR(-ENOMEM); - - conf->dev = dev; - - return conf; + return dev; } EXPORT_SYMBOL_GPL(vb2_dma_contig_init_ctx);
void vb2_dma_contig_cleanup_ctx(void *alloc_ctx) { - kfree(alloc_ctx); } EXPORT_SYMBOL_GPL(vb2_dma_contig_cleanup_ctx);
From: Laurent Pinchart laurent.pinchart@ideasonboard.com
Group functions by buffer type.
Signed-off-by: Laurent Pinchart laurent.pinchart@ideasonboard.com --- drivers/media/video/videobuf2-dma-contig.c | 92 ++++++++++++++++------------ 1 file changed, 54 insertions(+), 38 deletions(-)
diff --git a/drivers/media/video/videobuf2-dma-contig.c b/drivers/media/video/videobuf2-dma-contig.c index a019cd1..42c6431 100644 --- a/drivers/media/video/videobuf2-dma-contig.c +++ b/drivers/media/video/videobuf2-dma-contig.c @@ -21,14 +21,56 @@ struct vb2_dc_buf { struct device *dev; void *vaddr; - dma_addr_t dma_addr; unsigned long size; - struct vm_area_struct *vma; - atomic_t refcount; + dma_addr_t dma_addr; + + /* MMAP related */ struct vb2_vmarea_handler handler; + atomic_t refcount; + + /* USERPTR related */ + struct vm_area_struct *vma; };
-static void vb2_dc_put(void *buf_priv); +/*********************************************/ +/* callbacks for all buffers */ +/*********************************************/ + +static void *vb2_dc_cookie(void *buf_priv) +{ + struct vb2_dc_buf *buf = buf_priv; + + return &buf->dma_addr; +} + +static void *vb2_dc_vaddr(void *buf_priv) +{ + struct vb2_dc_buf *buf = buf_priv; + + return buf->vaddr; +} + +static unsigned int vb2_dc_num_users(void *buf_priv) +{ + struct vb2_dc_buf *buf = buf_priv; + + return atomic_read(&buf->refcount); +} + +/*********************************************/ +/* callbacks for MMAP buffers */ +/*********************************************/ + +static void vb2_dc_put(void *buf_priv) +{ + struct vb2_dc_buf *buf = buf_priv; + + if (!atomic_dec_and_test(&buf->refcount)) + return; + + dma_free_coherent(buf->dev, buf->size, buf->vaddr, buf->dma_addr); + kfree(buf); +}
static void *vb2_dc_alloc(void *alloc_ctx, unsigned long size) { @@ -58,40 +100,6 @@ static void *vb2_dc_alloc(void *alloc_ctx, unsigned long size) return buf; }
-static void vb2_dc_put(void *buf_priv) -{ - struct vb2_dc_buf *buf = buf_priv; - - if (atomic_dec_and_test(&buf->refcount)) { - dma_free_coherent(buf->dev, buf->size, buf->vaddr, - buf->dma_addr); - kfree(buf); - } -} - -static void *vb2_dc_cookie(void *buf_priv) -{ - struct vb2_dc_buf *buf = buf_priv; - - return &buf->dma_addr; -} - -static void *vb2_dc_vaddr(void *buf_priv) -{ - struct vb2_dc_buf *buf = buf_priv; - if (!buf) - return NULL; - - return buf->vaddr; -} - -static unsigned int vb2_dc_num_users(void *buf_priv) -{ - struct vb2_dc_buf *buf = buf_priv; - - return atomic_read(&buf->refcount); -} - static int vb2_dc_mmap(void *buf_priv, struct vm_area_struct *vma) { struct vb2_dc_buf *buf = buf_priv; @@ -105,6 +113,10 @@ static int vb2_dc_mmap(void *buf_priv, struct vm_area_struct *vma) &vb2_common_vm_ops, &buf->handler); }
+/*********************************************/ +/* callbacks for USERPTR buffers */ +/*********************************************/ + static void *vb2_dc_get_userptr(void *alloc_ctx, unsigned long vaddr, unsigned long size, int write) { @@ -143,6 +155,10 @@ static void vb2_dc_put_userptr(void *mem_priv) kfree(buf); }
+/*********************************************/ +/* DMA CONTIG exported functions */ +/*********************************************/ + const struct vb2_mem_ops vb2_dma_contig_memops = { .alloc = vb2_dc_alloc, .put = vb2_dc_put,
This patch introduces usage of dma_map_sg to map memory behind a userspace pointer to a device as dma-contiguous mapping.
This patch contains some of the code kindly provided by Marek Szyprowski m.szyprowski@samsung.com and Kamil Debski k.debski@samsung.com and Andrzej Pietrasiewicz andrzej.p@samsung.com. Kind thanks for bug reports from Laurent Pinchart laurent.pinchart@ideasonboard.com and Seung-Woo Kim sw0312.kim@samsung.com.
Signed-off-by: Tomasz Stanislawski t.stanislaws@samsung.com Signed-off-by: Kyungmin Park kyungmin.park@samsung.com Acked-by: Laurent Pinchart laurent.pinchart@ideasonboard.com --- drivers/media/video/videobuf2-dma-contig.c | 268 ++++++++++++++++++++++++++-- 1 file changed, 252 insertions(+), 16 deletions(-)
diff --git a/drivers/media/video/videobuf2-dma-contig.c b/drivers/media/video/videobuf2-dma-contig.c index 42c6431..068ec11 100644 --- a/drivers/media/video/videobuf2-dma-contig.c +++ b/drivers/media/video/videobuf2-dma-contig.c @@ -11,6 +11,8 @@ */
#include <linux/module.h> +#include <linux/scatterlist.h> +#include <linux/sched.h> #include <linux/slab.h> #include <linux/dma-mapping.h>
@@ -23,6 +25,8 @@ struct vb2_dc_buf { void *vaddr; unsigned long size; dma_addr_t dma_addr; + enum dma_data_direction dma_dir; + struct sg_table *dma_sgt;
/* MMAP related */ struct vb2_vmarea_handler handler; @@ -33,6 +37,95 @@ struct vb2_dc_buf { };
/*********************************************/ +/* scatterlist table functions */ +/*********************************************/ + +static struct sg_table *vb2_dc_pages_to_sgt(struct page **pages, + unsigned int n_pages, unsigned long offset, unsigned long size) +{ + struct sg_table *sgt; + unsigned int chunks; + unsigned int i; + unsigned int cur_page; + int ret; + struct scatterlist *s; + + sgt = kzalloc(sizeof *sgt, GFP_KERNEL); + if (!sgt) + return ERR_PTR(-ENOMEM); + + /* compute number of chunks */ + chunks = 1; + for (i = 1; i < n_pages; ++i) + if (pages[i] != pages[i - 1] + 1) + ++chunks; + + ret = sg_alloc_table(sgt, chunks, GFP_KERNEL); + if (ret) { + kfree(sgt); + return ERR_PTR(-ENOMEM); + } + + /* merging chunks and putting them into the scatterlist */ + cur_page = 0; + for_each_sg(sgt->sgl, s, sgt->orig_nents, i) { + unsigned long chunk_size; + unsigned int j; + + for (j = cur_page + 1; j < n_pages; ++j) + if (pages[j] != pages[j - 1] + 1) + break; + + chunk_size = ((j - cur_page) << PAGE_SHIFT) - offset; + sg_set_page(s, pages[cur_page], min(size, chunk_size), offset); + size -= chunk_size; + offset = 0; + cur_page = j; + } + + return sgt; +} + +static void vb2_dc_release_sgtable(struct sg_table *sgt) +{ + sg_free_table(sgt); + kfree(sgt); +} + +static void vb2_dc_sgt_foreach_page(struct sg_table *sgt, + void (*cb)(struct page *pg)) +{ + struct scatterlist *s; + unsigned int i; + + for_each_sg(sgt->sgl, s, sgt->nents, i) { + struct page *page = sg_page(s); + unsigned int n_pages = PAGE_ALIGN(s->offset + s->length) + >> PAGE_SHIFT; + unsigned int j; + + for (j = 0; j < n_pages; ++j, ++page) + cb(page); + } +} + +static unsigned long vb2_dc_get_contiguous_size(struct sg_table *sgt) +{ + struct scatterlist *s; + dma_addr_t expected = sg_dma_address(sgt->sgl); + unsigned int i; + unsigned long size = 0; + + for_each_sg(sgt->sgl, s, sgt->nents, i) { + if (sg_dma_address(s) != expected) + break; + expected = sg_dma_address(s) + sg_dma_len(s); + size += sg_dma_len(s); + } + return size; +} + +/*********************************************/ /* callbacks for all buffers */ /*********************************************/
@@ -117,42 +210,185 @@ static int vb2_dc_mmap(void *buf_priv, struct vm_area_struct *vma) /* callbacks for USERPTR buffers */ /*********************************************/
+static inline int vma_is_io(struct vm_area_struct *vma) +{ + return !!(vma->vm_flags & (VM_IO | VM_PFNMAP)); +} + +static int vb2_dc_get_user_pages(unsigned long start, struct page **pages, + int n_pages, struct vm_area_struct *vma, int write) +{ + if (vma_is_io(vma)) { + unsigned int i; + + for (i = 0; i < n_pages; ++i, start += PAGE_SIZE) { + unsigned long pfn; + int ret = follow_pfn(vma, start, &pfn); + + if (ret) { + printk(KERN_ERR "no page for address %lu\n", + start); + return ret; + } + pages[i] = pfn_to_page(pfn); + } + } else { + int n; + + n = get_user_pages(current, current->mm, start & PAGE_MASK, + n_pages, write, 1, pages, NULL); + /* negative error means that no page was pinned */ + n = max(n, 0); + if (n != n_pages) { + printk(KERN_ERR "got only %d of %d user pages\n", + n, n_pages); + while (n) + put_page(pages[--n]); + return -EFAULT; + } + } + + return 0; +} + +static void vb2_dc_put_dirty_page(struct page *page) +{ + set_page_dirty_lock(page); + put_page(page); +} + +static void vb2_dc_put_userptr(void *buf_priv) +{ + struct vb2_dc_buf *buf = buf_priv; + struct sg_table *sgt = buf->dma_sgt; + + dma_unmap_sg(buf->dev, sgt->sgl, sgt->orig_nents, buf->dma_dir); + if (!vma_is_io(buf->vma)) + vb2_dc_sgt_foreach_page(sgt, vb2_dc_put_dirty_page); + + vb2_dc_release_sgtable(sgt); + vb2_put_vma(buf->vma); + kfree(buf); +} + static void *vb2_dc_get_userptr(void *alloc_ctx, unsigned long vaddr, - unsigned long size, int write) + unsigned long size, int write) { struct vb2_dc_buf *buf; + unsigned long start; + unsigned long end; + unsigned long offset; + struct page **pages; + int n_pages; + int ret = 0; struct vm_area_struct *vma; - dma_addr_t dma_addr = 0; - int ret; + struct sg_table *sgt; + unsigned long contig_size;
buf = kzalloc(sizeof *buf, GFP_KERNEL); if (!buf) return ERR_PTR(-ENOMEM);
- ret = vb2_get_contig_userptr(vaddr, size, &vma, &dma_addr); + buf->dev = alloc_ctx; + buf->dma_dir = write ? DMA_FROM_DEVICE : DMA_TO_DEVICE; + + start = vaddr & PAGE_MASK; + offset = vaddr & ~PAGE_MASK; + end = PAGE_ALIGN(vaddr + size); + n_pages = (end - start) >> PAGE_SHIFT; + + pages = kmalloc(n_pages * sizeof pages[0], GFP_KERNEL); + if (!pages) { + ret = -ENOMEM; + printk(KERN_ERR "failed to allocate pages table\n"); + goto fail_buf; + } + + /* current->mm->mmap_sem is taken by videobuf2 core */ + vma = find_vma(current->mm, vaddr); + if (!vma) { + printk(KERN_ERR "no vma for address %lu\n", vaddr); + ret = -EFAULT; + goto fail_pages; + } + + if (vma->vm_end < vaddr + size) { + printk(KERN_ERR "vma at %lu is too small for %lu bytes\n", + vaddr, size); + ret = -EFAULT; + goto fail_pages; + } + + buf->vma = vb2_get_vma(vma); + if (!buf->vma) { + printk(KERN_ERR "failed to copy vma\n"); + ret = -ENOMEM; + goto fail_pages; + } + + /* extract page list from userspace mapping */ + ret = vb2_dc_get_user_pages(start, pages, n_pages, vma, write); if (ret) { - printk(KERN_ERR "Failed acquiring VMA for vaddr 0x%08lx\n", - vaddr); - kfree(buf); - return ERR_PTR(ret); + printk(KERN_ERR "failed to get user pages\n"); + goto fail_vma; + } + + sgt = vb2_dc_pages_to_sgt(pages, n_pages, offset, size); + if (IS_ERR(sgt)) { + printk(KERN_ERR "failed to create scatterlist table\n"); + ret = -ENOMEM; + goto fail_get_user_pages; }
+ /* pages are no longer needed */ + kfree(pages); + pages = NULL; + + sgt->nents = dma_map_sg(buf->dev, sgt->sgl, sgt->orig_nents, + buf->dma_dir); + if (sgt->nents <= 0) { + printk(KERN_ERR "failed to map scatterlist\n"); + ret = -EIO; + goto fail_sgt; + } + + contig_size = vb2_dc_get_contiguous_size(sgt); + if (contig_size < size) { + printk(KERN_ERR "contiguous mapping is too small %lu/%lu\n", + contig_size, size); + ret = -EFAULT; + goto fail_map_sg; + } + + buf->dma_addr = sg_dma_address(sgt->sgl); buf->size = size; - buf->dma_addr = dma_addr; - buf->vma = vma; + buf->dma_sgt = sgt;
return buf; -}
-static void vb2_dc_put_userptr(void *mem_priv) -{ - struct vb2_dc_buf *buf = mem_priv; +fail_map_sg: + dma_unmap_sg(buf->dev, sgt->sgl, sgt->nents, buf->dma_dir);
- if (!buf) - return; +fail_sgt: + if (!vma_is_io(buf->vma)) + vb2_dc_sgt_foreach_page(sgt, put_page); + vb2_dc_release_sgtable(sgt);
+fail_get_user_pages: + if (pages && !vma_is_io(buf->vma)) + while (n_pages) + put_page(pages[--n_pages]); + +fail_vma: vb2_put_vma(buf->vma); + +fail_pages: + kfree(pages); /* kfree is NULL-proof */ + +fail_buf: kfree(buf); + + return ERR_PTR(ret); }
/*********************************************/
From: Marek Szyprowski m.szyprowski@samsung.com
This patch adds support for prepare/finish callbacks in VB2 allocators. These callback are used for buffer flushing.
Signed-off-by: Marek Szyprowski m.szyprowski@samsung.com Acked-by: Laurent Pinchart laurent.pinchart@ideasonboard.com --- drivers/media/video/videobuf2-core.c | 11 +++++++++++ include/media/videobuf2-core.h | 7 +++++++ 2 files changed, 18 insertions(+)
diff --git a/drivers/media/video/videobuf2-core.c b/drivers/media/video/videobuf2-core.c index f43cfa4..d60ed25 100644 --- a/drivers/media/video/videobuf2-core.c +++ b/drivers/media/video/videobuf2-core.c @@ -845,6 +845,7 @@ void vb2_buffer_done(struct vb2_buffer *vb, enum vb2_buffer_state state) { struct vb2_queue *q = vb->vb2_queue; unsigned long flags; + unsigned int plane;
if (vb->state != VB2_BUF_STATE_ACTIVE) return; @@ -855,6 +856,10 @@ void vb2_buffer_done(struct vb2_buffer *vb, enum vb2_buffer_state state) dprintk(4, "Done processing on buffer %d, state: %d\n", vb->v4l2_buf.index, vb->state);
+ /* sync buffers */ + for (plane = 0; plane < vb->num_planes; ++plane) + call_memop(q, finish, vb->planes[plane].mem_priv); + /* Add the buffer to the done buffers list */ spin_lock_irqsave(&q->done_lock, flags); vb->state = state; @@ -1137,9 +1142,15 @@ err: static void __enqueue_in_driver(struct vb2_buffer *vb) { struct vb2_queue *q = vb->vb2_queue; + unsigned int plane;
vb->state = VB2_BUF_STATE_ACTIVE; atomic_inc(&q->queued_count); + + /* sync buffers */ + for (plane = 0; plane < vb->num_planes; ++plane) + call_memop(q, prepare, vb->planes[plane].mem_priv); + q->ops->buf_queue(vb); }
diff --git a/include/media/videobuf2-core.h b/include/media/videobuf2-core.h index 859bbaf..d079f92 100644 --- a/include/media/videobuf2-core.h +++ b/include/media/videobuf2-core.h @@ -56,6 +56,10 @@ struct vb2_fileio_data; * dmabuf * @unmap_dmabuf: releases access control to the dmabuf - allocator is notified * that this driver is done using the dmabuf for now + * @prepare: called everytime the buffer is passed from userspace to the + * driver, usefull for cache synchronisation, optional + * @finish: called everytime the buffer is passed back from the driver + * to the userspace, also optional * @vaddr: return a kernel virtual address to a given memory buffer * associated with the passed private structure or NULL if no * such mapping exists @@ -82,6 +86,9 @@ struct vb2_mem_ops { unsigned long size, int write); void (*put_userptr)(void *buf_priv);
+ void (*prepare)(void *buf_priv); + void (*finish)(void *buf_priv); + void *(*attach_dmabuf)(void *alloc_ctx, struct dma_buf *dbuf, unsigned long size, int write); void (*detach_dmabuf)(void *buf_priv);
From: Marek Szyprowski m.szyprowski@samsung.com
Add prepare/finish callbacks to vb2-dma-contig allocator.
Signed-off-by: Marek Szyprowski m.szyprowski@samsung.com --- drivers/media/video/videobuf2-dma-contig.c | 24 ++++++++++++++++++++++++ 1 file changed, 24 insertions(+)
diff --git a/drivers/media/video/videobuf2-dma-contig.c b/drivers/media/video/videobuf2-dma-contig.c index 068ec11..bb32e7e 100644 --- a/drivers/media/video/videobuf2-dma-contig.c +++ b/drivers/media/video/videobuf2-dma-contig.c @@ -150,6 +150,28 @@ static unsigned int vb2_dc_num_users(void *buf_priv) return atomic_read(&buf->refcount); }
+static void vb2_dc_prepare(void *buf_priv) +{ + struct vb2_dc_buf *buf = buf_priv; + struct sg_table *sgt = buf->dma_sgt; + + if (!sgt) + return; + + dma_sync_sg_for_device(buf->dev, sgt->sgl, sgt->nents, buf->dma_dir); +} + +static void vb2_dc_finish(void *buf_priv) +{ + struct vb2_dc_buf *buf = buf_priv; + struct sg_table *sgt = buf->dma_sgt; + + if (!sgt) + return; + + dma_sync_sg_for_cpu(buf->dev, sgt->sgl, sgt->nents, buf->dma_dir); +} + /*********************************************/ /* callbacks for MMAP buffers */ /*********************************************/ @@ -403,6 +425,8 @@ const struct vb2_mem_ops vb2_dma_contig_memops = { .mmap = vb2_dc_mmap, .get_userptr = vb2_dc_get_userptr, .put_userptr = vb2_dc_put_userptr, + .prepare = vb2_dc_prepare, + .finish = vb2_dc_finish, .num_users = vb2_dc_num_users, }; EXPORT_SYMBOL_GPL(vb2_dma_contig_memops);
From: Sumit Semwal sumit.semwal@ti.com
This patch makes changes for adding dma-contig as a dma_buf user. It provides function implementations for the {attach, detach, map, unmap}_dmabuf() mem_ops of DMABUF memory type.
Signed-off-by: Sumit Semwal sumit.semwal@ti.com Signed-off-by: Sumit Semwal sumit.semwal@linaro.org [author of the original patch] Signed-off-by: Tomasz Stanislawski t.stanislaws@samsung.com [integration with refactored dma-contig allocator] Acked-by: Laurent Pinchart laurent.pinchart@ideasonboard.com --- drivers/media/video/videobuf2-dma-contig.c | 119 +++++++++++++++++++++++++++- 1 file changed, 117 insertions(+), 2 deletions(-)
diff --git a/drivers/media/video/videobuf2-dma-contig.c b/drivers/media/video/videobuf2-dma-contig.c index bb32e7e..9c213bc 100644 --- a/drivers/media/video/videobuf2-dma-contig.c +++ b/drivers/media/video/videobuf2-dma-contig.c @@ -10,6 +10,7 @@ * the Free Software Foundation. */
+#include <linux/dma-buf.h> #include <linux/module.h> #include <linux/scatterlist.h> #include <linux/sched.h> @@ -34,6 +35,9 @@ struct vb2_dc_buf {
/* USERPTR related */ struct vm_area_struct *vma; + + /* DMABUF related */ + struct dma_buf_attachment *db_attach; };
/*********************************************/ @@ -155,7 +159,8 @@ static void vb2_dc_prepare(void *buf_priv) struct vb2_dc_buf *buf = buf_priv; struct sg_table *sgt = buf->dma_sgt;
- if (!sgt) + /* DMABUF exporter will flush the cache for us */ + if (!sgt || buf->db_attach) return;
dma_sync_sg_for_device(buf->dev, sgt->sgl, sgt->nents, buf->dma_dir); @@ -166,7 +171,8 @@ static void vb2_dc_finish(void *buf_priv) struct vb2_dc_buf *buf = buf_priv; struct sg_table *sgt = buf->dma_sgt;
- if (!sgt) + /* DMABUF exporter will flush the cache for us */ + if (!sgt || buf->db_attach) return;
dma_sync_sg_for_cpu(buf->dev, sgt->sgl, sgt->nents, buf->dma_dir); @@ -414,6 +420,111 @@ fail_buf: }
/*********************************************/ +/* callbacks for DMABUF buffers */ +/*********************************************/ + +static int vb2_dc_map_dmabuf(void *mem_priv) +{ + struct vb2_dc_buf *buf = mem_priv; + struct sg_table *sgt; + unsigned long contig_size; + + if (WARN_ON(!buf->db_attach)) { + printk(KERN_ERR "trying to pin a non attached buffer\n"); + return -EINVAL; + } + + if (WARN_ON(buf->dma_sgt)) { + printk(KERN_ERR "dmabuf buffer is already pinned\n"); + return 0; + } + + /* get the associated scatterlist for this buffer */ + sgt = dma_buf_map_attachment(buf->db_attach, buf->dma_dir); + if (IS_ERR_OR_NULL(sgt)) { + printk(KERN_ERR "Error getting dmabuf scatterlist\n"); + return -EINVAL; + } + + /* checking if dmabuf is big enough to store contiguous chunk */ + contig_size = vb2_dc_get_contiguous_size(sgt); + if (contig_size < buf->size) { + printk(KERN_ERR "contiguous chunk is too small %lu/%lu b\n", + contig_size, buf->size); + dma_buf_unmap_attachment(buf->db_attach, sgt, buf->dma_dir); + return -EFAULT; + } + + buf->dma_addr = sg_dma_address(sgt->sgl); + buf->dma_sgt = sgt; + + return 0; +} + +static void vb2_dc_unmap_dmabuf(void *mem_priv) +{ + struct vb2_dc_buf *buf = mem_priv; + struct sg_table *sgt = buf->dma_sgt; + + if (WARN_ON(!buf->db_attach)) { + printk(KERN_ERR "trying to unpin a not attached buffer\n"); + return; + } + + if (WARN_ON(!sgt)) { + printk(KERN_ERR "dmabuf buffer is already unpinned\n"); + return; + } + + dma_buf_unmap_attachment(buf->db_attach, sgt, buf->dma_dir); + + buf->dma_addr = 0; + buf->dma_sgt = NULL; +} + +static void vb2_dc_detach_dmabuf(void *mem_priv) +{ + struct vb2_dc_buf *buf = mem_priv; + + /* if vb2 works correctly you should never detach mapped buffer */ + if (WARN_ON(buf->dma_addr)) + vb2_dc_unmap_dmabuf(buf); + + /* detach this attachment */ + dma_buf_detach(buf->db_attach->dmabuf, buf->db_attach); + kfree(buf); +} + +static void *vb2_dc_attach_dmabuf(void *alloc_ctx, struct dma_buf *dbuf, + unsigned long size, int write) +{ + struct vb2_dc_buf *buf; + struct dma_buf_attachment *dba; + + if (dbuf->size < size) + return ERR_PTR(-EFAULT); + + buf = kzalloc(sizeof *buf, GFP_KERNEL); + if (!buf) + return ERR_PTR(-ENOMEM); + + buf->dev = alloc_ctx; + /* create attachment for the dmabuf with the user device */ + dba = dma_buf_attach(dbuf, buf->dev); + if (IS_ERR(dba)) { + printk(KERN_ERR "failed to attach dmabuf\n"); + kfree(buf); + return dba; + } + + buf->dma_dir = write ? DMA_FROM_DEVICE : DMA_TO_DEVICE; + buf->size = size; + buf->db_attach = dba; + + return buf; +} + +/*********************************************/ /* DMA CONTIG exported functions */ /*********************************************/
@@ -427,6 +538,10 @@ const struct vb2_mem_ops vb2_dma_contig_memops = { .put_userptr = vb2_dc_put_userptr, .prepare = vb2_dc_prepare, .finish = vb2_dc_finish, + .map_dmabuf = vb2_dc_map_dmabuf, + .unmap_dmabuf = vb2_dc_unmap_dmabuf, + .attach_dmabuf = vb2_dc_attach_dmabuf, + .detach_dmabuf = vb2_dc_detach_dmabuf, .num_users = vb2_dc_num_users, }; EXPORT_SYMBOL_GPL(vb2_dma_contig_memops);
This patch enhances s5p-tv with support for DMABUF importing via V4L2_MEMORY_DMABUF memory type.
Signed-off-by: Tomasz Stanislawski t.stanislaws@samsung.com Signed-off-by: Kyungmin Park kyungmin.park@samsung.com --- drivers/media/video/s5p-tv/Kconfig | 1 + drivers/media/video/s5p-tv/mixer_video.c | 2 +- 2 files changed, 2 insertions(+), 1 deletion(-)
diff --git a/drivers/media/video/s5p-tv/Kconfig b/drivers/media/video/s5p-tv/Kconfig index f248b28..2e80126 100644 --- a/drivers/media/video/s5p-tv/Kconfig +++ b/drivers/media/video/s5p-tv/Kconfig @@ -10,6 +10,7 @@ config VIDEO_SAMSUNG_S5P_TV bool "Samsung TV driver for S5P platform (experimental)" depends on PLAT_S5P && PM_RUNTIME depends on EXPERIMENTAL + select DMA_SHARED_BUFFER default n ---help--- Say Y here to enable selecting the TV output devices for diff --git a/drivers/media/video/s5p-tv/mixer_video.c b/drivers/media/video/s5p-tv/mixer_video.c index 33fde2a..cff974a 100644 --- a/drivers/media/video/s5p-tv/mixer_video.c +++ b/drivers/media/video/s5p-tv/mixer_video.c @@ -1078,7 +1078,7 @@ struct mxr_layer *mxr_base_layer_create(struct mxr_device *mdev,
layer->vb_queue = (struct vb2_queue) { .type = V4L2_BUF_TYPE_VIDEO_OUTPUT_MPLANE, - .io_modes = VB2_MMAP | VB2_USERPTR, + .io_modes = VB2_MMAP | VB2_USERPTR | VB2_DMABUF, .drv_priv = layer, .buf_struct_size = sizeof(struct mxr_buffer), .ops = &mxr_video_qops,
This patch enhances s5p-fimc with support for DMABUF importing via V4L2_MEMORY_DMABUF memory type.
Signed-off-by: Tomasz Stanislawski t.stanislaws@samsung.com Signed-off-by: Kyungmin Park kyungmin.park@samsung.com Acked-by: Sylwester Nawrocki s.nawrocki@samsung.com --- drivers/media/video/s5p-fimc/Kconfig | 1 + drivers/media/video/s5p-fimc/fimc-capture.c | 2 +- 2 files changed, 2 insertions(+), 1 deletion(-)
diff --git a/drivers/media/video/s5p-fimc/Kconfig b/drivers/media/video/s5p-fimc/Kconfig index a564f7e..3106026 100644 --- a/drivers/media/video/s5p-fimc/Kconfig +++ b/drivers/media/video/s5p-fimc/Kconfig @@ -14,6 +14,7 @@ config VIDEO_S5P_FIMC depends on I2C select VIDEOBUF2_DMA_CONTIG select V4L2_MEM2MEM_DEV + select DMA_SHARED_BUFFER help This is a V4L2 driver for Samsung S5P and EXYNOS4 SoC camera host interface and video postprocessor (FIMC and FIMC-LITE) devices. diff --git a/drivers/media/video/s5p-fimc/fimc-capture.c b/drivers/media/video/s5p-fimc/fimc-capture.c index 3545745..cd27e33 100644 --- a/drivers/media/video/s5p-fimc/fimc-capture.c +++ b/drivers/media/video/s5p-fimc/fimc-capture.c @@ -1609,7 +1609,7 @@ static int fimc_register_capture_device(struct fimc_dev *fimc, q = &fimc->vid_cap.vbq; memset(q, 0, sizeof(*q)); q->type = V4L2_BUF_TYPE_VIDEO_CAPTURE_MPLANE; - q->io_modes = VB2_MMAP | VB2_USERPTR; + q->io_modes = VB2_MMAP | VB2_USERPTR | VB2_DMABUF; q->drv_priv = fimc->vid_cap.ctx; q->ops = &fimc_capture_qops; q->mem_ops = &vb2_dma_contig_memops;
Hi Tomasz,
On Wednesday 23 May 2012 14:10:14 Tomasz Stanislawski wrote:
Hello everyone, This patchset adds support for DMABUF [2] importing to V4L2 stack. The support for DMABUF exporting was moved to separate patchset due to dependency on patches for DMA mapping redesign by Marek Szyprowski [4].
Except for the small issue with patches 01/13 and 02/13, the set is ready for upstream as far as I'm concerned.
v6:
- fixed missing entry in v4l2_memory_names
- fixed a bug occuring after get_user_pages failure
I've missed that one, what was it ?
- fixed a bug caused by using invalid vma for get_user_pages
- prepare/finish no longer call dma_sync for dmabuf buffers
v5:
- removed change of importer/exporter behaviour
- fixes vb2_dc_pages_to_sgt basing on Laurent's hints
- changed pin/unpin words to lock/unlock in Doc
v4:
- rebased on mainline 3.4-rc2
- included missing importing support for s5p-fimc and s5p-tv
- added patch for changing map/unmap for importers
- fixes to Documentation part
- coding style fixes
- pairing {map/unmap}_dmabuf in vb2-core
- fixing variable types and semantic of arguments in videobufb2-dma-contig.c
v3:
- rebased on mainline 3.4-rc1
- split 'code refactor' patch to multiple smaller patches
- squashed fixes to Sumit's patches
- patchset is no longer dependant on 'DMA mapping redesign'
- separated path for handling IO and non-IO mappings
- add documentation for DMABUF importing to V4L
- removed all DMABUF exporter related code
- removed usage of dma_get_pages extension
v2:
- extended VIDIOC_EXPBUF argument from integer memoffset to struct v4l2_exportbuffer
- added patch that breaks DMABUF spec on (un)map_atachment callcacks but
allows to work with existing implementation of DMABUF prime in DRM
- all dma-contig code refactoring patches were squashed
- bugfixes
v1: List of changes since [1].
- support for DMA api extension dma_get_pages, the function is used to
retrieve pages used to create DMA mapping.
- small fixes/code cleanup to videobuf2
- added prepare and finish callbacks to vb2 allocators, it is used keep consistency between dma-cpu acess to the memory (by Marek Szyprowski)
- support for exporting of DMABUF buffer in V4L2 and Videobuf2, originated
from [3].
- support for dma-buf exporting in vb2-dma-contig allocator
- support for DMABUF for s5p-tv and s5p-fimc (capture interface) drivers, originated from [3]
- changed handling for userptr buffers (by Marek Szyprowski, Andrzej Pietrasiewicz)
- let mmap method to use dma_mmap_writecombine call (by Marek Szyprowski)
[1] http://thread.gmane.org/gmane.linux.drivers.video-input-infrastructure/4296 6/focus=42968 [2] https://lkml.org/lkml/2011/12/26/29 [3] http://thread.gmane.org/gmane.linux.drivers.video-input-infrastructure/3635 4/focus=36355 [4] http://thread.gmane.org/gmane.linux.kernel.cross-arch/12819
Laurent Pinchart (2): v4l: vb2-dma-contig: Shorten vb2_dma_contig prefix to vb2_dc v4l: vb2-dma-contig: Reorder functions
Marek Szyprowski (2): v4l: vb2: add prepare/finish callbacks to allocators v4l: vb2-dma-contig: add prepare/finish to dma-contig allocator
Sumit Semwal (4): v4l: Add DMABUF as a memory type v4l: vb2: add support for shared buffer (dma_buf) v4l: vb: remove warnings about MEMORY_DMABUF v4l: vb2-dma-contig: add support for dma_buf importing
Tomasz Stanislawski (5): Documentation: media: description of DMABUF importing in V4L2 v4l: vb2-dma-contig: Remove unneeded allocation context structure v4l: vb2-dma-contig: add support for scatterlist in userptr mode v4l: s5p-tv: mixer: support for dmabuf importing v4l: s5p-fimc: support for dmabuf importing
Documentation/DocBook/media/v4l/compat.xml | 4 + Documentation/DocBook/media/v4l/io.xml | 179 +++++++ .../DocBook/media/v4l/vidioc-create-bufs.xml | 1 + Documentation/DocBook/media/v4l/vidioc-qbuf.xml | 15 + Documentation/DocBook/media/v4l/vidioc-reqbufs.xml | 45 +- drivers/media/video/s5p-fimc/Kconfig | 1 + drivers/media/video/s5p-fimc/fimc-capture.c | 2 +- drivers/media/video/s5p-tv/Kconfig | 1 + drivers/media/video/s5p-tv/mixer_video.c | 2 +- drivers/media/video/v4l2-ioctl.c | 1 + drivers/media/video/videobuf-core.c | 4 + drivers/media/video/videobuf2-core.c | 207 +++++++- drivers/media/video/videobuf2-dma-contig.c | 520 ++++++++++++++--- include/linux/videodev2.h | 7 + include/media/videobuf2-core.h | 34 ++ 15 files changed, 924 insertions(+), 99 deletions(-)
On Tue, May 29, 2012 at 6:25 AM, Laurent Pinchart laurent.pinchart@ideasonboard.com wrote:
Hi Tomasz,
Hi Tomasz, Laurent, Mauro,
On Wednesday 23 May 2012 14:10:14 Tomasz Stanislawski wrote:
Hello everyone, This patchset adds support for DMABUF [2] importing to V4L2 stack. The support for DMABUF exporting was moved to separate patchset due to dependency on patches for DMA mapping redesign by Marek Szyprowski [4].
Except for the small issue with patches 01/13 and 02/13, the set is ready for upstream as far as I'm concerned.
+1; Mauro: how do you think about this series? Getting it landed into 3.5 would make life lot easier :)
v6:
- fixed missing entry in v4l2_memory_names
- fixed a bug occuring after get_user_pages failure
I've missed that one, what was it ?
- fixed a bug caused by using invalid vma for get_user_pages
- prepare/finish no longer call dma_sync for dmabuf buffers
v5:
- removed change of importer/exporter behaviour
- fixes vb2_dc_pages_to_sgt basing on Laurent's hints
- changed pin/unpin words to lock/unlock in Doc
v4:
- rebased on mainline 3.4-rc2
- included missing importing support for s5p-fimc and s5p-tv
- added patch for changing map/unmap for importers
- fixes to Documentation part
- coding style fixes
- pairing {map/unmap}_dmabuf in vb2-core
- fixing variable types and semantic of arguments in videobufb2-dma-contig.c
v3:
- rebased on mainline 3.4-rc1
- split 'code refactor' patch to multiple smaller patches
- squashed fixes to Sumit's patches
- patchset is no longer dependant on 'DMA mapping redesign'
- separated path for handling IO and non-IO mappings
- add documentation for DMABUF importing to V4L
- removed all DMABUF exporter related code
- removed usage of dma_get_pages extension
v2:
- extended VIDIOC_EXPBUF argument from integer memoffset to struct
v4l2_exportbuffer
- added patch that breaks DMABUF spec on (un)map_atachment callcacks but
allows to work with existing implementation of DMABUF prime in DRM
- all dma-contig code refactoring patches were squashed
- bugfixes
v1: List of changes since [1].
- support for DMA api extension dma_get_pages, the function is used to
retrieve pages used to create DMA mapping.
- small fixes/code cleanup to videobuf2
- added prepare and finish callbacks to vb2 allocators, it is used keep
consistency between dma-cpu acess to the memory (by Marek Szyprowski)
- support for exporting of DMABUF buffer in V4L2 and Videobuf2, originated
from [3].
- support for dma-buf exporting in vb2-dma-contig allocator
- support for DMABUF for s5p-tv and s5p-fimc (capture interface) drivers,
originated from [3]
- changed handling for userptr buffers (by Marek Szyprowski, Andrzej
Pietrasiewicz)
- let mmap method to use dma_mmap_writecombine call (by Marek Szyprowski)
[1] http://thread.gmane.org/gmane.linux.drivers.video-input-infrastructure/4296 6/focus=42968 [2] https://lkml.org/lkml/2011/12/26/29 [3] http://thread.gmane.org/gmane.linux.drivers.video-input-infrastructure/3635 4/focus=36355 [4] http://thread.gmane.org/gmane.linux.kernel.cross-arch/12819
Laurent Pinchart (2): v4l: vb2-dma-contig: Shorten vb2_dma_contig prefix to vb2_dc v4l: vb2-dma-contig: Reorder functions
Marek Szyprowski (2): v4l: vb2: add prepare/finish callbacks to allocators v4l: vb2-dma-contig: add prepare/finish to dma-contig allocator
Sumit Semwal (4): v4l: Add DMABUF as a memory type v4l: vb2: add support for shared buffer (dma_buf) v4l: vb: remove warnings about MEMORY_DMABUF v4l: vb2-dma-contig: add support for dma_buf importing
Tomasz Stanislawski (5): Documentation: media: description of DMABUF importing in V4L2 v4l: vb2-dma-contig: Remove unneeded allocation context structure v4l: vb2-dma-contig: add support for scatterlist in userptr mode v4l: s5p-tv: mixer: support for dmabuf importing v4l: s5p-fimc: support for dmabuf importing
Documentation/DocBook/media/v4l/compat.xml | 4 + Documentation/DocBook/media/v4l/io.xml | 179 +++++++ .../DocBook/media/v4l/vidioc-create-bufs.xml | 1 + Documentation/DocBook/media/v4l/vidioc-qbuf.xml | 15 + Documentation/DocBook/media/v4l/vidioc-reqbufs.xml | 45 +- drivers/media/video/s5p-fimc/Kconfig | 1 + drivers/media/video/s5p-fimc/fimc-capture.c | 2 +- drivers/media/video/s5p-tv/Kconfig | 1 + drivers/media/video/s5p-tv/mixer_video.c | 2 +- drivers/media/video/v4l2-ioctl.c | 1 + drivers/media/video/videobuf-core.c | 4 + drivers/media/video/videobuf2-core.c | 207 +++++++- drivers/media/video/videobuf2-dma-contig.c | 520 ++++++++++++++--- include/linux/videodev2.h | 7 + include/media/videobuf2-core.h | 34 ++ 15 files changed, 924 insertions(+), 99 deletions(-)
-- Regards,
Laurent Pinchart
Best regards, ~Sumit.
I have a system where the data is planar, but the kernel drivers expect to get one allocation with offsets for the planes. I can't figure out how to do that with the current dma_buf implementation. I thought I could pass the same dma_buf several times and use the data_offset field of the v4l2_plane struct but it looks like that's only for output. Am I missing something? Is this supported?
Thanks, Rebecca
On Wed, May 30, 2012 at 8:26 AM, Semwal, Sumit sumit.semwal@ti.com wrote:
On Tue, May 29, 2012 at 6:25 AM, Laurent Pinchart laurent.pinchart@ideasonboard.com wrote:
Hi Tomasz,
Hi Tomasz, Laurent, Mauro,
On Wednesday 23 May 2012 14:10:14 Tomasz Stanislawski wrote:
Hello everyone, This patchset adds support for DMABUF [2] importing to V4L2 stack. The support for DMABUF exporting was moved to separate patchset due to dependency on patches for DMA mapping redesign by Marek Szyprowski [4].
Except for the small issue with patches 01/13 and 02/13, the set is ready for upstream as far as I'm concerned.
+1; Mauro: how do you think about this series? Getting it landed into 3.5 would make life lot easier :)
v6:
- fixed missing entry in v4l2_memory_names
- fixed a bug occuring after get_user_pages failure
I've missed that one, what was it ?
- fixed a bug caused by using invalid vma for get_user_pages
- prepare/finish no longer call dma_sync for dmabuf buffers
v5:
- removed change of importer/exporter behaviour
- fixes vb2_dc_pages_to_sgt basing on Laurent's hints
- changed pin/unpin words to lock/unlock in Doc
v4:
- rebased on mainline 3.4-rc2
- included missing importing support for s5p-fimc and s5p-tv
- added patch for changing map/unmap for importers
- fixes to Documentation part
- coding style fixes
- pairing {map/unmap}_dmabuf in vb2-core
- fixing variable types and semantic of arguments in videobufb2-dma-contig.c
v3:
- rebased on mainline 3.4-rc1
- split 'code refactor' patch to multiple smaller patches
- squashed fixes to Sumit's patches
- patchset is no longer dependant on 'DMA mapping redesign'
- separated path for handling IO and non-IO mappings
- add documentation for DMABUF importing to V4L
- removed all DMABUF exporter related code
- removed usage of dma_get_pages extension
v2:
- extended VIDIOC_EXPBUF argument from integer memoffset to struct
v4l2_exportbuffer
- added patch that breaks DMABUF spec on (un)map_atachment callcacks but
allows to work with existing implementation of DMABUF prime in DRM
- all dma-contig code refactoring patches were squashed
- bugfixes
v1: List of changes since [1].
- support for DMA api extension dma_get_pages, the function is used to
retrieve pages used to create DMA mapping.
- small fixes/code cleanup to videobuf2
- added prepare and finish callbacks to vb2 allocators, it is used keep
consistency between dma-cpu acess to the memory (by Marek Szyprowski)
- support for exporting of DMABUF buffer in V4L2 and Videobuf2, originated
from [3].
- support for dma-buf exporting in vb2-dma-contig allocator
- support for DMABUF for s5p-tv and s5p-fimc (capture interface) drivers,
originated from [3]
- changed handling for userptr buffers (by Marek Szyprowski, Andrzej
Pietrasiewicz)
- let mmap method to use dma_mmap_writecombine call (by Marek Szyprowski)
[1] http://thread.gmane.org/gmane.linux.drivers.video-input-infrastructure/4296 6/focus=42968 [2] https://lkml.org/lkml/2011/12/26/29 [3] http://thread.gmane.org/gmane.linux.drivers.video-input-infrastructure/3635 4/focus=36355 [4] http://thread.gmane.org/gmane.linux.kernel.cross-arch/12819
Laurent Pinchart (2): v4l: vb2-dma-contig: Shorten vb2_dma_contig prefix to vb2_dc v4l: vb2-dma-contig: Reorder functions
Marek Szyprowski (2): v4l: vb2: add prepare/finish callbacks to allocators v4l: vb2-dma-contig: add prepare/finish to dma-contig allocator
Sumit Semwal (4): v4l: Add DMABUF as a memory type v4l: vb2: add support for shared buffer (dma_buf) v4l: vb: remove warnings about MEMORY_DMABUF v4l: vb2-dma-contig: add support for dma_buf importing
Tomasz Stanislawski (5): Documentation: media: description of DMABUF importing in V4L2 v4l: vb2-dma-contig: Remove unneeded allocation context structure v4l: vb2-dma-contig: add support for scatterlist in userptr mode v4l: s5p-tv: mixer: support for dmabuf importing v4l: s5p-fimc: support for dmabuf importing
Documentation/DocBook/media/v4l/compat.xml | 4 + Documentation/DocBook/media/v4l/io.xml | 179 +++++++ .../DocBook/media/v4l/vidioc-create-bufs.xml | 1 + Documentation/DocBook/media/v4l/vidioc-qbuf.xml | 15 + Documentation/DocBook/media/v4l/vidioc-reqbufs.xml | 45 +- drivers/media/video/s5p-fimc/Kconfig | 1 + drivers/media/video/s5p-fimc/fimc-capture.c | 2 +- drivers/media/video/s5p-tv/Kconfig | 1 + drivers/media/video/s5p-tv/mixer_video.c | 2 +- drivers/media/video/v4l2-ioctl.c | 1 + drivers/media/video/videobuf-core.c | 4 + drivers/media/video/videobuf2-core.c | 207 +++++++- drivers/media/video/videobuf2-dma-contig.c | 520 ++++++++++++++--- include/linux/videodev2.h | 7 + include/media/videobuf2-core.h | 34 ++ 15 files changed, 924 insertions(+), 99 deletions(-)
-- Regards,
Laurent Pinchart
Best regards, ~Sumit.
Linaro-mm-sig mailing list Linaro-mm-sig@lists.linaro.org http://lists.linaro.org/mailman/listinfo/linaro-mm-sig
this is at least how we do it w/ drm/kms.. I would expect that if you could do that w/ output for v4l you also could for input, but perhaps the individual driver needs to do something to support mplane? I guess the v4l folks would know better
BR, -R
On Tue, Jun 5, 2012 at 3:34 AM, Rebecca Schultz Zavin rebecca@android.com wrote:
I have a system where the data is planar, but the kernel drivers expect to get one allocation with offsets for the planes. I can't figure out how to do that with the current dma_buf implementation. I thought I could pass the same dma_buf several times and use the data_offset field of the v4l2_plane struct but it looks like that's only for output. Am I missing something? Is this supported?
Thanks, Rebecca
On Wed, May 30, 2012 at 8:26 AM, Semwal, Sumit sumit.semwal@ti.com wrote:
On Tue, May 29, 2012 at 6:25 AM, Laurent Pinchart laurent.pinchart@ideasonboard.com wrote:
Hi Tomasz,
Hi Tomasz, Laurent, Mauro,
On Wednesday 23 May 2012 14:10:14 Tomasz Stanislawski wrote:
Hello everyone, This patchset adds support for DMABUF [2] importing to V4L2 stack. The support for DMABUF exporting was moved to separate patchset due to dependency on patches for DMA mapping redesign by Marek Szyprowski [4].
Except for the small issue with patches 01/13 and 02/13, the set is ready for upstream as far as I'm concerned.
+1; Mauro: how do you think about this series? Getting it landed into 3.5 would make life lot easier :)
v6:
- fixed missing entry in v4l2_memory_names
- fixed a bug occuring after get_user_pages failure
I've missed that one, what was it ?
- fixed a bug caused by using invalid vma for get_user_pages
- prepare/finish no longer call dma_sync for dmabuf buffers
v5:
- removed change of importer/exporter behaviour
- fixes vb2_dc_pages_to_sgt basing on Laurent's hints
- changed pin/unpin words to lock/unlock in Doc
v4:
- rebased on mainline 3.4-rc2
- included missing importing support for s5p-fimc and s5p-tv
- added patch for changing map/unmap for importers
- fixes to Documentation part
- coding style fixes
- pairing {map/unmap}_dmabuf in vb2-core
- fixing variable types and semantic of arguments in videobufb2-dma-contig.c
v3:
- rebased on mainline 3.4-rc1
- split 'code refactor' patch to multiple smaller patches
- squashed fixes to Sumit's patches
- patchset is no longer dependant on 'DMA mapping redesign'
- separated path for handling IO and non-IO mappings
- add documentation for DMABUF importing to V4L
- removed all DMABUF exporter related code
- removed usage of dma_get_pages extension
v2:
- extended VIDIOC_EXPBUF argument from integer memoffset to struct
v4l2_exportbuffer
- added patch that breaks DMABUF spec on (un)map_atachment callcacks but
allows to work with existing implementation of DMABUF prime in DRM
- all dma-contig code refactoring patches were squashed
- bugfixes
v1: List of changes since [1].
- support for DMA api extension dma_get_pages, the function is used to
retrieve pages used to create DMA mapping.
- small fixes/code cleanup to videobuf2
- added prepare and finish callbacks to vb2 allocators, it is used keep
consistency between dma-cpu acess to the memory (by Marek Szyprowski)
- support for exporting of DMABUF buffer in V4L2 and Videobuf2, originated
from [3].
- support for dma-buf exporting in vb2-dma-contig allocator
- support for DMABUF for s5p-tv and s5p-fimc (capture interface) drivers,
originated from [3]
- changed handling for userptr buffers (by Marek Szyprowski, Andrzej
Pietrasiewicz)
- let mmap method to use dma_mmap_writecombine call (by Marek Szyprowski)
[1] http://thread.gmane.org/gmane.linux.drivers.video-input-infrastructure/4296 6/focus=42968 [2] https://lkml.org/lkml/2011/12/26/29 [3] http://thread.gmane.org/gmane.linux.drivers.video-input-infrastructure/3635 4/focus=36355 [4] http://thread.gmane.org/gmane.linux.kernel.cross-arch/12819
Laurent Pinchart (2): v4l: vb2-dma-contig: Shorten vb2_dma_contig prefix to vb2_dc v4l: vb2-dma-contig: Reorder functions
Marek Szyprowski (2): v4l: vb2: add prepare/finish callbacks to allocators v4l: vb2-dma-contig: add prepare/finish to dma-contig allocator
Sumit Semwal (4): v4l: Add DMABUF as a memory type v4l: vb2: add support for shared buffer (dma_buf) v4l: vb: remove warnings about MEMORY_DMABUF v4l: vb2-dma-contig: add support for dma_buf importing
Tomasz Stanislawski (5): Documentation: media: description of DMABUF importing in V4L2 v4l: vb2-dma-contig: Remove unneeded allocation context structure v4l: vb2-dma-contig: add support for scatterlist in userptr mode v4l: s5p-tv: mixer: support for dmabuf importing v4l: s5p-fimc: support for dmabuf importing
Documentation/DocBook/media/v4l/compat.xml | 4 + Documentation/DocBook/media/v4l/io.xml | 179 +++++++ .../DocBook/media/v4l/vidioc-create-bufs.xml | 1 + Documentation/DocBook/media/v4l/vidioc-qbuf.xml | 15 + Documentation/DocBook/media/v4l/vidioc-reqbufs.xml | 45 +- drivers/media/video/s5p-fimc/Kconfig | 1 + drivers/media/video/s5p-fimc/fimc-capture.c | 2 +- drivers/media/video/s5p-tv/Kconfig | 1 + drivers/media/video/s5p-tv/mixer_video.c | 2 +- drivers/media/video/v4l2-ioctl.c | 1 + drivers/media/video/videobuf-core.c | 4 + drivers/media/video/videobuf2-core.c | 207 +++++++- drivers/media/video/videobuf2-dma-contig.c | 520 ++++++++++++++--- include/linux/videodev2.h | 7 + include/media/videobuf2-core.h | 34 ++ 15 files changed, 924 insertions(+), 99 deletions(-)
-- Regards,
Laurent Pinchart
Best regards, ~Sumit.
Linaro-mm-sig mailing list Linaro-mm-sig@lists.linaro.org http://lists.linaro.org/mailman/listinfo/linaro-mm-sig
I'm trying to do it in my drivier, but I'm not sure how to make it safe since there is no way to tell the kernel the total size of the buffer. From what I can tell, I can't sanity check that the offset and lengths are within the buffer without adding a field.
Rebecca
On Mon, Jun 4, 2012 at 1:28 PM, Rob Clark robdclark@gmail.com wrote:
this is at least how we do it w/ drm/kms.. I would expect that if you could do that w/ output for v4l you also could for input, but perhaps the individual driver needs to do something to support mplane? I guess the v4l folks would know better
BR, -R
On Tue, Jun 5, 2012 at 3:34 AM, Rebecca Schultz Zavin rebecca@android.com wrote:
I have a system where the data is planar, but the kernel drivers expect to get one allocation with offsets for the planes. I can't figure out how to do that with the current dma_buf implementation. I thought I could pass the same dma_buf several times and use the data_offset field of the v4l2_plane struct but it looks like that's only for output. Am I missing something? Is this supported?
Thanks, Rebecca
On Wed, May 30, 2012 at 8:26 AM, Semwal, Sumit sumit.semwal@ti.com wrote:
On Tue, May 29, 2012 at 6:25 AM, Laurent Pinchart laurent.pinchart@ideasonboard.com wrote:
Hi Tomasz,
Hi Tomasz, Laurent, Mauro,
On Wednesday 23 May 2012 14:10:14 Tomasz Stanislawski wrote:
Hello everyone, This patchset adds support for DMABUF [2] importing to V4L2 stack. The support for DMABUF exporting was moved to separate patchset due to dependency on patches for DMA mapping redesign by Marek Szyprowski [4].
Except for the small issue with patches 01/13 and 02/13, the set is ready for upstream as far as I'm concerned.
+1; Mauro: how do you think about this series? Getting it landed into 3.5 would make life lot easier :)
v6:
- fixed missing entry in v4l2_memory_names
- fixed a bug occuring after get_user_pages failure
I've missed that one, what was it ?
- fixed a bug caused by using invalid vma for get_user_pages
- prepare/finish no longer call dma_sync for dmabuf buffers
v5:
- removed change of importer/exporter behaviour
- fixes vb2_dc_pages_to_sgt basing on Laurent's hints
- changed pin/unpin words to lock/unlock in Doc
v4:
- rebased on mainline 3.4-rc2
- included missing importing support for s5p-fimc and s5p-tv
- added patch for changing map/unmap for importers
- fixes to Documentation part
- coding style fixes
- pairing {map/unmap}_dmabuf in vb2-core
- fixing variable types and semantic of arguments in videobufb2-dma-contig.c
v3:
- rebased on mainline 3.4-rc1
- split 'code refactor' patch to multiple smaller patches
- squashed fixes to Sumit's patches
- patchset is no longer dependant on 'DMA mapping redesign'
- separated path for handling IO and non-IO mappings
- add documentation for DMABUF importing to V4L
- removed all DMABUF exporter related code
- removed usage of dma_get_pages extension
v2:
- extended VIDIOC_EXPBUF argument from integer memoffset to struct
v4l2_exportbuffer
- added patch that breaks DMABUF spec on (un)map_atachment callcacks but
allows to work with existing implementation of DMABUF prime in DRM
- all dma-contig code refactoring patches were squashed
- bugfixes
v1: List of changes since [1].
- support for DMA api extension dma_get_pages, the function is used to
retrieve pages used to create DMA mapping.
- small fixes/code cleanup to videobuf2
- added prepare and finish callbacks to vb2 allocators, it is used keep
consistency between dma-cpu acess to the memory (by Marek Szyprowski)
- support for exporting of DMABUF buffer in V4L2 and Videobuf2, originated
from [3].
- support for dma-buf exporting in vb2-dma-contig allocator
- support for DMABUF for s5p-tv and s5p-fimc (capture interface) drivers,
originated from [3]
- changed handling for userptr buffers (by Marek Szyprowski, Andrzej
Pietrasiewicz)
- let mmap method to use dma_mmap_writecombine call (by Marek Szyprowski)
[1] http://thread.gmane.org/gmane.linux.drivers.video-input-infrastructure/4296 6/focus=42968 [2] https://lkml.org/lkml/2011/12/26/29 [3] http://thread.gmane.org/gmane.linux.drivers.video-input-infrastructure/3635 4/focus=36355 [4] http://thread.gmane.org/gmane.linux.kernel.cross-arch/12819
Laurent Pinchart (2): v4l: vb2-dma-contig: Shorten vb2_dma_contig prefix to vb2_dc v4l: vb2-dma-contig: Reorder functions
Marek Szyprowski (2): v4l: vb2: add prepare/finish callbacks to allocators v4l: vb2-dma-contig: add prepare/finish to dma-contig allocator
Sumit Semwal (4): v4l: Add DMABUF as a memory type v4l: vb2: add support for shared buffer (dma_buf) v4l: vb: remove warnings about MEMORY_DMABUF v4l: vb2-dma-contig: add support for dma_buf importing
Tomasz Stanislawski (5): Documentation: media: description of DMABUF importing in V4L2 v4l: vb2-dma-contig: Remove unneeded allocation context structure v4l: vb2-dma-contig: add support for scatterlist in userptr mode v4l: s5p-tv: mixer: support for dmabuf importing v4l: s5p-fimc: support for dmabuf importing
Documentation/DocBook/media/v4l/compat.xml | 4 + Documentation/DocBook/media/v4l/io.xml | 179 +++++++ .../DocBook/media/v4l/vidioc-create-bufs.xml | 1 + Documentation/DocBook/media/v4l/vidioc-qbuf.xml | 15 + Documentation/DocBook/media/v4l/vidioc-reqbufs.xml | 45 +- drivers/media/video/s5p-fimc/Kconfig | 1 + drivers/media/video/s5p-fimc/fimc-capture.c | 2 +- drivers/media/video/s5p-tv/Kconfig | 1 + drivers/media/video/s5p-tv/mixer_video.c | 2 +- drivers/media/video/v4l2-ioctl.c | 1 + drivers/media/video/videobuf-core.c | 4 + drivers/media/video/videobuf2-core.c | 207 +++++++- drivers/media/video/videobuf2-dma-contig.c | 520 ++++++++++++++--- include/linux/videodev2.h | 7 + include/media/videobuf2-core.h | 34 ++ 15 files changed, 924 insertions(+), 99 deletions(-)
-- Regards,
Laurent Pinchart
Best regards, ~Sumit.
Linaro-mm-sig mailing list Linaro-mm-sig@lists.linaro.org http://lists.linaro.org/mailman/listinfo/linaro-mm-sig
Also the data_offset field (and bytes_used field) only get copied from the v4l2_buffer into the vb2_buffer struct if the buffer is an output buffer.
Rebecca
On Mon, Jun 4, 2012 at 1:46 PM, Rebecca Schultz Zavin rebecca@android.com wrote:
I'm trying to do it in my drivier, but I'm not sure how to make it safe since there is no way to tell the kernel the total size of the buffer. From what I can tell, I can't sanity check that the offset and lengths are within the buffer without adding a field.
Rebecca
On Mon, Jun 4, 2012 at 1:28 PM, Rob Clark robdclark@gmail.com wrote:
this is at least how we do it w/ drm/kms.. I would expect that if you could do that w/ output for v4l you also could for input, but perhaps the individual driver needs to do something to support mplane? I guess the v4l folks would know better
BR, -R
On Tue, Jun 5, 2012 at 3:34 AM, Rebecca Schultz Zavin rebecca@android.com wrote:
I have a system where the data is planar, but the kernel drivers expect to get one allocation with offsets for the planes. I can't figure out how to do that with the current dma_buf implementation. I thought I could pass the same dma_buf several times and use the data_offset field of the v4l2_plane struct but it looks like that's only for output. Am I missing something? Is this supported?
Thanks, Rebecca
On Wed, May 30, 2012 at 8:26 AM, Semwal, Sumit sumit.semwal@ti.com wrote:
On Tue, May 29, 2012 at 6:25 AM, Laurent Pinchart laurent.pinchart@ideasonboard.com wrote:
Hi Tomasz,
Hi Tomasz, Laurent, Mauro,
On Wednesday 23 May 2012 14:10:14 Tomasz Stanislawski wrote:
Hello everyone, This patchset adds support for DMABUF [2] importing to V4L2 stack. The support for DMABUF exporting was moved to separate patchset due to dependency on patches for DMA mapping redesign by Marek Szyprowski [4].
Except for the small issue with patches 01/13 and 02/13, the set is ready for upstream as far as I'm concerned.
+1; Mauro: how do you think about this series? Getting it landed into 3.5 would make life lot easier :)
v6:
- fixed missing entry in v4l2_memory_names
- fixed a bug occuring after get_user_pages failure
I've missed that one, what was it ?
- fixed a bug caused by using invalid vma for get_user_pages
- prepare/finish no longer call dma_sync for dmabuf buffers
v5:
- removed change of importer/exporter behaviour
- fixes vb2_dc_pages_to_sgt basing on Laurent's hints
- changed pin/unpin words to lock/unlock in Doc
v4:
- rebased on mainline 3.4-rc2
- included missing importing support for s5p-fimc and s5p-tv
- added patch for changing map/unmap for importers
- fixes to Documentation part
- coding style fixes
- pairing {map/unmap}_dmabuf in vb2-core
- fixing variable types and semantic of arguments in videobufb2-dma-contig.c
v3:
- rebased on mainline 3.4-rc1
- split 'code refactor' patch to multiple smaller patches
- squashed fixes to Sumit's patches
- patchset is no longer dependant on 'DMA mapping redesign'
- separated path for handling IO and non-IO mappings
- add documentation for DMABUF importing to V4L
- removed all DMABUF exporter related code
- removed usage of dma_get_pages extension
v2:
- extended VIDIOC_EXPBUF argument from integer memoffset to struct
v4l2_exportbuffer
- added patch that breaks DMABUF spec on (un)map_atachment callcacks but
allows to work with existing implementation of DMABUF prime in DRM
- all dma-contig code refactoring patches were squashed
- bugfixes
v1: List of changes since [1].
- support for DMA api extension dma_get_pages, the function is used to
retrieve pages used to create DMA mapping.
- small fixes/code cleanup to videobuf2
- added prepare and finish callbacks to vb2 allocators, it is used keep
consistency between dma-cpu acess to the memory (by Marek Szyprowski)
- support for exporting of DMABUF buffer in V4L2 and Videobuf2, originated
from [3].
- support for dma-buf exporting in vb2-dma-contig allocator
- support for DMABUF for s5p-tv and s5p-fimc (capture interface) drivers,
originated from [3]
- changed handling for userptr buffers (by Marek Szyprowski, Andrzej
Pietrasiewicz)
- let mmap method to use dma_mmap_writecombine call (by Marek Szyprowski)
[1] http://thread.gmane.org/gmane.linux.drivers.video-input-infrastructure/4296 6/focus=42968 [2] https://lkml.org/lkml/2011/12/26/29 [3] http://thread.gmane.org/gmane.linux.drivers.video-input-infrastructure/3635 4/focus=36355 [4] http://thread.gmane.org/gmane.linux.kernel.cross-arch/12819
Laurent Pinchart (2): v4l: vb2-dma-contig: Shorten vb2_dma_contig prefix to vb2_dc v4l: vb2-dma-contig: Reorder functions
Marek Szyprowski (2): v4l: vb2: add prepare/finish callbacks to allocators v4l: vb2-dma-contig: add prepare/finish to dma-contig allocator
Sumit Semwal (4): v4l: Add DMABUF as a memory type v4l: vb2: add support for shared buffer (dma_buf) v4l: vb: remove warnings about MEMORY_DMABUF v4l: vb2-dma-contig: add support for dma_buf importing
Tomasz Stanislawski (5): Documentation: media: description of DMABUF importing in V4L2 v4l: vb2-dma-contig: Remove unneeded allocation context structure v4l: vb2-dma-contig: add support for scatterlist in userptr mode v4l: s5p-tv: mixer: support for dmabuf importing v4l: s5p-fimc: support for dmabuf importing
Documentation/DocBook/media/v4l/compat.xml | 4 + Documentation/DocBook/media/v4l/io.xml | 179 +++++++ .../DocBook/media/v4l/vidioc-create-bufs.xml | 1 + Documentation/DocBook/media/v4l/vidioc-qbuf.xml | 15 + Documentation/DocBook/media/v4l/vidioc-reqbufs.xml | 45 +- drivers/media/video/s5p-fimc/Kconfig | 1 + drivers/media/video/s5p-fimc/fimc-capture.c | 2 +- drivers/media/video/s5p-tv/Kconfig | 1 + drivers/media/video/s5p-tv/mixer_video.c | 2 +- drivers/media/video/v4l2-ioctl.c | 1 + drivers/media/video/videobuf-core.c | 4 + drivers/media/video/videobuf2-core.c | 207 +++++++- drivers/media/video/videobuf2-dma-contig.c | 520 ++++++++++++++--- include/linux/videodev2.h | 7 + include/media/videobuf2-core.h | 34 ++ 15 files changed, 924 insertions(+), 99 deletions(-)
-- Regards,
Laurent Pinchart
Best regards, ~Sumit.
Linaro-mm-sig mailing list Linaro-mm-sig@lists.linaro.org http://lists.linaro.org/mailman/listinfo/linaro-mm-sig
can you check expected size vs dmabuf->size - offset?
On Tue, Jun 5, 2012 at 4:46 AM, Rebecca Schultz Zavin rebecca@android.com wrote:
I'm trying to do it in my drivier, but I'm not sure how to make it safe since there is no way to tell the kernel the total size of the buffer. From what I can tell, I can't sanity check that the offset and lengths are within the buffer without adding a field.
Rebecca
On Mon, Jun 4, 2012 at 1:28 PM, Rob Clark robdclark@gmail.com wrote:
this is at least how we do it w/ drm/kms.. I would expect that if you could do that w/ output for v4l you also could for input, but perhaps the individual driver needs to do something to support mplane? I guess the v4l folks would know better
BR, -R
On Tue, Jun 5, 2012 at 3:34 AM, Rebecca Schultz Zavin rebecca@android.com wrote:
I have a system where the data is planar, but the kernel drivers expect to get one allocation with offsets for the planes. I can't figure out how to do that with the current dma_buf implementation. I thought I could pass the same dma_buf several times and use the data_offset field of the v4l2_plane struct but it looks like that's only for output. Am I missing something? Is this supported?
Thanks, Rebecca
On Wed, May 30, 2012 at 8:26 AM, Semwal, Sumit sumit.semwal@ti.com wrote:
On Tue, May 29, 2012 at 6:25 AM, Laurent Pinchart laurent.pinchart@ideasonboard.com wrote:
Hi Tomasz,
Hi Tomasz, Laurent, Mauro,
On Wednesday 23 May 2012 14:10:14 Tomasz Stanislawski wrote:
Hello everyone, This patchset adds support for DMABUF [2] importing to V4L2 stack. The support for DMABUF exporting was moved to separate patchset due to dependency on patches for DMA mapping redesign by Marek Szyprowski [4].
Except for the small issue with patches 01/13 and 02/13, the set is ready for upstream as far as I'm concerned.
+1; Mauro: how do you think about this series? Getting it landed into 3.5 would make life lot easier :)
v6:
- fixed missing entry in v4l2_memory_names
- fixed a bug occuring after get_user_pages failure
I've missed that one, what was it ?
- fixed a bug caused by using invalid vma for get_user_pages
- prepare/finish no longer call dma_sync for dmabuf buffers
v5:
- removed change of importer/exporter behaviour
- fixes vb2_dc_pages_to_sgt basing on Laurent's hints
- changed pin/unpin words to lock/unlock in Doc
v4:
- rebased on mainline 3.4-rc2
- included missing importing support for s5p-fimc and s5p-tv
- added patch for changing map/unmap for importers
- fixes to Documentation part
- coding style fixes
- pairing {map/unmap}_dmabuf in vb2-core
- fixing variable types and semantic of arguments in videobufb2-dma-contig.c
v3:
- rebased on mainline 3.4-rc1
- split 'code refactor' patch to multiple smaller patches
- squashed fixes to Sumit's patches
- patchset is no longer dependant on 'DMA mapping redesign'
- separated path for handling IO and non-IO mappings
- add documentation for DMABUF importing to V4L
- removed all DMABUF exporter related code
- removed usage of dma_get_pages extension
v2:
- extended VIDIOC_EXPBUF argument from integer memoffset to struct
v4l2_exportbuffer
- added patch that breaks DMABUF spec on (un)map_atachment callcacks but
allows to work with existing implementation of DMABUF prime in DRM
- all dma-contig code refactoring patches were squashed
- bugfixes
v1: List of changes since [1].
- support for DMA api extension dma_get_pages, the function is used to
retrieve pages used to create DMA mapping.
- small fixes/code cleanup to videobuf2
- added prepare and finish callbacks to vb2 allocators, it is used keep
consistency between dma-cpu acess to the memory (by Marek Szyprowski)
- support for exporting of DMABUF buffer in V4L2 and Videobuf2, originated
from [3].
- support for dma-buf exporting in vb2-dma-contig allocator
- support for DMABUF for s5p-tv and s5p-fimc (capture interface) drivers,
originated from [3]
- changed handling for userptr buffers (by Marek Szyprowski, Andrzej
Pietrasiewicz)
- let mmap method to use dma_mmap_writecombine call (by Marek Szyprowski)
[1] http://thread.gmane.org/gmane.linux.drivers.video-input-infrastructure/4296 6/focus=42968 [2] https://lkml.org/lkml/2011/12/26/29 [3] http://thread.gmane.org/gmane.linux.drivers.video-input-infrastructure/3635 4/focus=36355 [4] http://thread.gmane.org/gmane.linux.kernel.cross-arch/12819
Laurent Pinchart (2): v4l: vb2-dma-contig: Shorten vb2_dma_contig prefix to vb2_dc v4l: vb2-dma-contig: Reorder functions
Marek Szyprowski (2): v4l: vb2: add prepare/finish callbacks to allocators v4l: vb2-dma-contig: add prepare/finish to dma-contig allocator
Sumit Semwal (4): v4l: Add DMABUF as a memory type v4l: vb2: add support for shared buffer (dma_buf) v4l: vb: remove warnings about MEMORY_DMABUF v4l: vb2-dma-contig: add support for dma_buf importing
Tomasz Stanislawski (5): Documentation: media: description of DMABUF importing in V4L2 v4l: vb2-dma-contig: Remove unneeded allocation context structure v4l: vb2-dma-contig: add support for scatterlist in userptr mode v4l: s5p-tv: mixer: support for dmabuf importing v4l: s5p-fimc: support for dmabuf importing
Documentation/DocBook/media/v4l/compat.xml | 4 + Documentation/DocBook/media/v4l/io.xml | 179 +++++++ .../DocBook/media/v4l/vidioc-create-bufs.xml | 1 + Documentation/DocBook/media/v4l/vidioc-qbuf.xml | 15 + Documentation/DocBook/media/v4l/vidioc-reqbufs.xml | 45 +- drivers/media/video/s5p-fimc/Kconfig | 1 + drivers/media/video/s5p-fimc/fimc-capture.c | 2 +- drivers/media/video/s5p-tv/Kconfig | 1 + drivers/media/video/s5p-tv/mixer_video.c | 2 +- drivers/media/video/v4l2-ioctl.c | 1 + drivers/media/video/videobuf-core.c | 4 + drivers/media/video/videobuf2-core.c | 207 +++++++- drivers/media/video/videobuf2-dma-contig.c | 520 ++++++++++++++--- include/linux/videodev2.h | 7 + include/media/videobuf2-core.h | 34 ++ 15 files changed, 924 insertions(+), 99 deletions(-)
-- Regards,
Laurent Pinchart
Best regards, ~Sumit.
Linaro-mm-sig mailing list Linaro-mm-sig@lists.linaro.org http://lists.linaro.org/mailman/listinfo/linaro-mm-sig
Hi Rebecca,
On Mon June 4 2012 21:34:23 Rebecca Schultz Zavin wrote:
I have a system where the data is planar, but the kernel drivers expect to get one allocation with offsets for the planes. I can't figure out how to do that with the current dma_buf implementation. I thought I could pass the same dma_buf several times and use the data_offset field of the v4l2_plane struct but it looks like that's only for output. Am I missing something? Is this supported?
v4l2_plane is typically used if the planes are allocated separately. If you allocate it in one go, aren't the planes then at well-defined offsets from the start? If so, then it is either one of the already pre-defined planar formats found here:
http://hverkuil.home.xs4all.nl/spec/media.html#yuv-formats
or you define a pixelformat specific to your own hardware that identifies that particular format.
If it is one allocation, but there is no clear calculation based on width and height that gives you the start of each plane, then we do not support that at the moment. I believe I had a discussion about something similar with people from Qualcomm, but that never came to anything.
That would be something to discuss on the linux-media mailinglist.
Regards,
Hans
It probably is a fixed offset, but all the information describing it is in userspace... In my experience, it's always almost one of the pre-defined formats, but then there's some extra padding, weird alignment etc. I'm trying to convert code that used userptr, but where the planes were offsets into the same buffer, to use dma_buf. Looks like I need to dig a bit deeper.
Thanks, Rebecca
On Mon, Jun 4, 2012 at 2:58 PM, Hans Verkuil hverkuil@xs4all.nl wrote:
Hi Rebecca,
On Mon June 4 2012 21:34:23 Rebecca Schultz Zavin wrote:
I have a system where the data is planar, but the kernel drivers expect to get one allocation with offsets for the planes. I can't figure out how to do that with the current dma_buf implementation. I thought I could pass the same dma_buf several times and use the data_offset field of the v4l2_plane struct but it looks like that's only for output. Am I missing something? Is this supported?
v4l2_plane is typically used if the planes are allocated separately. If you allocate it in one go, aren't the planes then at well-defined offsets from the start? If so, then it is either one of the already pre-defined planar formats found here:
http://hverkuil.home.xs4all.nl/spec/media.html#yuv-formats
or you define a pixelformat specific to your own hardware that identifies that particular format.
If it is one allocation, but there is no clear calculation based on width and height that gives you the start of each plane, then we do not support that at the moment. I believe I had a discussion about something similar with people from Qualcomm, but that never came to anything.
That would be something to discuss on the linux-media mailinglist.
Regards,
Hans
On Mon June 4 2012 23:58:07 Hans Verkuil wrote:
Hi Rebecca,
On Mon June 4 2012 21:34:23 Rebecca Schultz Zavin wrote:
I have a system where the data is planar, but the kernel drivers expect to get one allocation with offsets for the planes. I can't figure out how to do that with the current dma_buf implementation. I thought I could pass the same dma_buf several times and use the data_offset field of the v4l2_plane struct but it looks like that's only for output. Am I missing something? Is this supported?
v4l2_plane is typically used if the planes are allocated separately. If you allocate it in one go, aren't the planes then at well-defined offsets from the start? If so, then it is either one of the already pre-defined planar formats found here:
http://hverkuil.home.xs4all.nl/spec/media.html#yuv-formats
or you define a pixelformat specific to your own hardware that identifies that particular format.
If it is one allocation, but there is no clear calculation based on width and height that gives you the start of each plane, then we do not support that at the moment. I believe I had a discussion about something similar with people from Qualcomm, but that never came to anything.
It took some digging, but this was the enhancement proposed for a Qualcomm problem:
http://www.spinics.net/lists/linux-media/msg40376.html
This may or may not be what you are looking for.
Regards,
Hans
That would be something to discuss on the linux-media mailinglist.
Regards,
Hans
Linaro-mm-sig mailing list Linaro-mm-sig@lists.linaro.org http://lists.linaro.org/mailman/listinfo/linaro-mm-sig
Hi Rebecca,
On Monday 04 June 2012 12:34:23 Rebecca Schultz Zavin wrote:
I have a system where the data is planar, but the kernel drivers expect to get one allocation with offsets for the planes. I can't figure out how to do that with the current dma_buf implementation. I thought I could pass the same dma_buf several times and use the data_offset field of the v4l2_plane struct but it looks like that's only for output. Am I missing something? Is this supported?
data_offset is indeed for video output only at the moment, and doesn't seem to be used by any driver in mainline for now.
I can't really see a reason why data_offset couldn't be used for video capture devices as well.
Sanity checks are currently missing. For output devices we should check that data_offset + bytesused < length in the vb2 core. For input devices the check will have to be performed by drivers. Taking data_offset into account automatically would also be useful. I think most of that should be possible to implement in the allocators.
On Wed 6 June 2012 05:46:34 Laurent Pinchart wrote:
Hi Rebecca,
On Monday 04 June 2012 12:34:23 Rebecca Schultz Zavin wrote:
I have a system where the data is planar, but the kernel drivers expect to get one allocation with offsets for the planes. I can't figure out how to do that with the current dma_buf implementation. I thought I could pass the same dma_buf several times and use the data_offset field of the v4l2_plane struct but it looks like that's only for output. Am I missing something? Is this supported?
data_offset is indeed for video output only at the moment, and doesn't seem to be used by any driver in mainline for now.
Actually, data_offset may be set by capture drivers. For output buffers it is set by userspace, for capture buffers it is set by the driver. This data_offset typically contains meta data.
I can't really see a reason why data_offset couldn't be used for video capture devices as well.
Sanity checks are currently missing. For output devices we should check that data_offset + bytesused < length in the vb2 core. For input devices the check will have to be performed by drivers. Taking data_offset into account automatically would also be useful. I think most of that should be possible to implement in the allocators.
See this proposal of how to solve this:
http://www.spinics.net/lists/linux-media/msg40376.html
Regards,
Hans
Hi Hans,
On Wednesday 06 June 2012 10:17:03 Hans Verkuil wrote:
On Wed 6 June 2012 05:46:34 Laurent Pinchart wrote:
On Monday 04 June 2012 12:34:23 Rebecca Schultz Zavin wrote:
I have a system where the data is planar, but the kernel drivers expect to get one allocation with offsets for the planes. I can't figure out how to do that with the current dma_buf implementation. I thought I could pass the same dma_buf several times and use the data_offset field of the v4l2_plane struct but it looks like that's only for output. Am I missing something? Is this supported?
data_offset is indeed for video output only at the moment, and doesn't seem to be used by any driver in mainline for now.
Actually, data_offset may be set by capture drivers. For output buffers it is set by userspace, for capture buffers it is set by the driver. This data_offset typically contains meta data.
Is that documented somewhere ? I wasn't aware of this use case.
I can't really see a reason why data_offset couldn't be used for video capture devices as well.
Sanity checks are currently missing. For output devices we should check that data_offset + bytesused < length in the vb2 core. For input devices the check will have to be performed by drivers. Taking data_offset into account automatically would also be useful. I think most of that should be possible to implement in the allocators.
See this proposal of how to solve this:
This requires more discussions regarding how the app_offset and data_offset fields should be used for the different memory types we support.
For instance app_offset would not make that much sense for the USERPTR memory type, as we can include the offset in the user pointer already (using app_offset there would only make the code more complex without any added benefit).
For the MMAP memory type adding an app_offset would require allocating buffers large enough to accomodate the offset, and would thus only be useful with CREATE_BUFS. I'm also wondering whether the main use case (passing the buffer to another device that requires that app_offset) wouldn't be better addressed by the DMABUF memory type anyway.
Comments are welcome.
On Thu June 7 2012 02:52:06 Laurent Pinchart wrote:
Hi Hans,
On Wednesday 06 June 2012 10:17:03 Hans Verkuil wrote:
On Wed 6 June 2012 05:46:34 Laurent Pinchart wrote:
On Monday 04 June 2012 12:34:23 Rebecca Schultz Zavin wrote:
I have a system where the data is planar, but the kernel drivers expect to get one allocation with offsets for the planes. I can't figure out how to do that with the current dma_buf implementation. I thought I could pass the same dma_buf several times and use the data_offset field of the v4l2_plane struct but it looks like that's only for output. Am I missing something? Is this supported?
data_offset is indeed for video output only at the moment, and doesn't seem to be used by any driver in mainline for now.
Actually, data_offset may be set by capture drivers. For output buffers it is set by userspace, for capture buffers it is set by the driver. This data_offset typically contains meta data.
Is that documented somewhere ? I wasn't aware of this use case.
It is documented in the proposal that Pawel sent, but very poorly if at all in the spec. That needs to be improved.
I can't really see a reason why data_offset couldn't be used for video capture devices as well.
Sanity checks are currently missing. For output devices we should check that data_offset + bytesused < length in the vb2 core. For input devices the check will have to be performed by drivers. Taking data_offset into account automatically would also be useful. I think most of that should be possible to implement in the allocators.
See this proposal of how to solve this:
This requires more discussions regarding how the app_offset and data_offset fields should be used for the different memory types we support.
For instance app_offset would not make that much sense for the USERPTR memory type, as we can include the offset in the user pointer already (using app_offset there would only make the code more complex without any added benefit).
For the MMAP memory type adding an app_offset would require allocating buffers large enough to accomodate the offset, and would thus only be useful with CREATE_BUFS. I'm also wondering whether the main use case (passing the buffer to another device that requires that app_offset) wouldn't be better addressed by the DMABUF memory type anyway.
I'm not going to pursue this unless Google indicates that they need this. And actually I would suggest that they ask Pawel to work on this, after all he made the proposal AND he works for Google :-)
Regards,
Hans
Hi,
On 06/07/2012 08:43 AM, Hans Verkuil wrote:
On Thu June 7 2012 02:52:06 Laurent Pinchart wrote:
On Wednesday 06 June 2012 10:17:03 Hans Verkuil wrote:
On Wed 6 June 2012 05:46:34 Laurent Pinchart wrote:
On Monday 04 June 2012 12:34:23 Rebecca Schultz Zavin wrote:
I have a system where the data is planar, but the kernel drivers expect to get one allocation with offsets for the planes. I can't figure out how to do that with the current dma_buf implementation. I thought I could pass the same dma_buf several times and use the data_offset field of the v4l2_plane struct but it looks like that's only for output. Am I missing something? Is this supported?
data_offset is indeed for video output only at the moment, and doesn't seem to be used by any driver in mainline for now.
Actually, data_offset may be set by capture drivers. For output buffers it is set by userspace, for capture buffers it is set by the driver. This data_offset typically contains meta data.
Is that documented somewhere ? I wasn't aware of this use case.
It is documented in the proposal that Pawel sent, but very poorly if at all in the spec. That needs to be improved.
I can't really see a reason why data_offset couldn't be used for video capture devices as well.
Sanity checks are currently missing. For output devices we should check that data_offset + bytesused< length in the vb2 core. For input devices the check will have to be performed by drivers. Taking data_offset into account automatically would also be useful. I think most of that should be possible to implement in the allocators.
See this proposal of how to solve this:
This requires more discussions regarding how the app_offset and data_offset fields should be used for the different memory types we support.
For instance app_offset would not make that much sense for the USERPTR memory type, as we can include the offset in the user pointer already (using app_offset there would only make the code more complex without any added benefit).
For the MMAP memory type adding an app_offset would require allocating buffers large enough to accomodate the offset, and would thus only be useful with CREATE_BUFS. I'm also wondering whether the main use case (passing the buffer to another device that requires that app_offset) wouldn't be better addressed by the DMABUF memory type anyway.
I think what is needed is a more flexible support for multi-planar data formats. Currently each plane involves separate memory allocation, which is not convenient in some use cases, at the least. For each plane a separate DMABUF object is needed.
Single allocation for several data planes could be also useful for some still image capture use cases, where an image sensor device outputs multiple data at once, which can only be written into single memory region. There is currently no standard way to retrieve data offsets and sizes in such cases.
It likely won't be trivial to cleanly integrate support for this with current V4L2 multi-plane API though.
I'm not going to pursue this unless Google indicates that they need this. And actually I would suggest that they ask Pawel to work on this, after all he made the proposal AND he works for Google :-)
-- Regards, Sylwester
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