diff options
author | Adrian Schmutzler <freifunk@adrianschmutzler.de> | 2020-02-08 21:58:55 +0100 |
---|---|---|
committer | Adrian Schmutzler <freifunk@adrianschmutzler.de> | 2020-02-14 14:10:51 +0100 |
commit | 7d7aa2fd924c27829ec25f825481554dd81bce97 (patch) | |
tree | 658b87b89331670266163e522ea5fb52535633cb /target/linux/bcm27xx/patches-4.19/950-0602-media-vb2-Allow-reqbufs-0-with-in-use-MMAP-buffers.patch | |
parent | e7bfda2c243e66a75ff966ba04c28b1590b5d24c (diff) | |
download | upstream-7d7aa2fd924c27829ec25f825481554dd81bce97.tar.gz upstream-7d7aa2fd924c27829ec25f825481554dd81bce97.tar.bz2 upstream-7d7aa2fd924c27829ec25f825481554dd81bce97.zip |
brcm2708: rename target to bcm27xx
This change makes the names of Broadcom targets consistent by using
the common notation based on SoC/CPU ID (which is used internally
anyway), bcmXXXX instead of brcmXXXX.
This is even used for target TITLE in make menuconfig already,
only the short target name used brcm so far.
Despite, since subtargets range from bcm2708 to bcm2711, it seems
appropriate to use bcm27xx instead of bcm2708 (again, as already done
for BOARDNAME).
This also renames the packages brcm2708-userland and brcm2708-gpu-fw.
Signed-off-by: Adrian Schmutzler <freifunk@adrianschmutzler.de>
Acked-by: Álvaro Fernández Rojas <noltari@gmail.com>
Diffstat (limited to 'target/linux/bcm27xx/patches-4.19/950-0602-media-vb2-Allow-reqbufs-0-with-in-use-MMAP-buffers.patch')
-rw-r--r-- | target/linux/bcm27xx/patches-4.19/950-0602-media-vb2-Allow-reqbufs-0-with-in-use-MMAP-buffers.patch | 130 |
1 files changed, 130 insertions, 0 deletions
diff --git a/target/linux/bcm27xx/patches-4.19/950-0602-media-vb2-Allow-reqbufs-0-with-in-use-MMAP-buffers.patch b/target/linux/bcm27xx/patches-4.19/950-0602-media-vb2-Allow-reqbufs-0-with-in-use-MMAP-buffers.patch new file mode 100644 index 0000000000..755ca34440 --- /dev/null +++ b/target/linux/bcm27xx/patches-4.19/950-0602-media-vb2-Allow-reqbufs-0-with-in-use-MMAP-buffers.patch @@ -0,0 +1,130 @@ +From 16cf378051d7fff6772a7acaecbacddec7822330 Mon Sep 17 00:00:00 2001 +From: John Sheu <sheu@chromium.org> +Date: Thu, 15 Nov 2018 10:57:16 -0500 +Subject: [PATCH] media: vb2: Allow reqbufs(0) with "in use" MMAP + buffers + +Upstream commit d644cca50f366cd109845ae92e37c09ed79adf81 + +Videobuf2 presently does not allow VIDIOC_REQBUFS to destroy outstanding +buffers if the queue is of type V4L2_MEMORY_MMAP, and if the buffers are +considered "in use". This is different behavior than for other memory +types and prevents us from deallocating buffers in following two cases: + +1) There are outstanding mmap()ed views on the buffer. However even if + we put the buffer in reqbufs(0), there will be remaining references, + due to vma .open/close() adjusting vb2 buffer refcount appropriately. + This means that the buffer will be in fact freed only when the last + mmap()ed view is unmapped. + +2) Buffer has been exported as a DMABUF. Refcount of the vb2 buffer + is managed properly by VB2 DMABUF ops, i.e. incremented on DMABUF + get and decremented on DMABUF release. This means that the buffer + will be alive until all importers release it. + +Considering both cases above, there does not seem to be any need to +prevent reqbufs(0) operation, because buffer lifetime is already +properly managed by both mmap() and DMABUF code paths. Let's remove it +and allow userspace freeing the queue (and potentially allocating a new +one) even though old buffers might be still in processing. + +To let userspace know that the kernel now supports orphaning buffers +that are still in use, add a new V4L2_BUF_CAP_SUPPORTS_ORPHANED_BUFS +to be set by reqbufs and create_bufs. + +[p.zabel@pengutronix.de: added V4L2_BUF_CAP_SUPPORTS_ORPHANED_BUFS, + updated documentation, and added back debug message] + +Signed-off-by: John Sheu <sheu@chromium.org> +Reviewed-by: Pawel Osciak <posciak@chromium.org> +Signed-off-by: Tomasz Figa <tfiga@chromium.org> +Signed-off-by: Philipp Zabel <p.zabel@pengutronix.de> +Acked-by: Sakari Ailus <sakari.ailus@linux.intel.com> +Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl> +[hverkuil-cisco@xs4all.nl: added V4L2-BUF-CAP-SUPPORTS-ORPHANED-BUFS ref] +Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org> +--- + Documentation/media/uapi/v4l/vidioc-reqbufs.rst | 17 ++++++++++++++--- + drivers/media/common/videobuf2/videobuf2-core.c | 8 +++----- + drivers/media/common/videobuf2/videobuf2-v4l2.c | 2 +- + include/uapi/linux/videodev2.h | 1 + + 4 files changed, 19 insertions(+), 9 deletions(-) + +--- a/Documentation/media/uapi/v4l/vidioc-reqbufs.rst ++++ b/Documentation/media/uapi/v4l/vidioc-reqbufs.rst +@@ -59,9 +59,14 @@ When the I/O method is not supported the + code. + + Applications can call :ref:`VIDIOC_REQBUFS` again to change the number of +-buffers, however this cannot succeed when any buffers are still mapped. +-A ``count`` value of zero frees all buffers, after aborting or finishing +-any DMA in progress, an implicit ++buffers. Note that if any buffers are still mapped or exported via DMABUF, ++then :ref:`VIDIOC_REQBUFS` can only succeed if the ++``V4L2_BUF_CAP_SUPPORTS_ORPHANED_BUFS`` capability is set. Otherwise ++:ref:`VIDIOC_REQBUFS` will return the ``EBUSY`` error code. ++If ``V4L2_BUF_CAP_SUPPORTS_ORPHANED_BUFS`` is set, then these buffers are ++orphaned and will be freed when they are unmapped or when the exported DMABUF ++fds are closed. A ``count`` value of zero frees or orphans all buffers, after ++aborting or finishing any DMA in progress, an implicit + :ref:`VIDIOC_STREAMOFF <VIDIOC_STREAMON>`. + + +@@ -112,6 +117,7 @@ any DMA in progress, an implicit + .. _V4L2-BUF-CAP-SUPPORTS-USERPTR: + .. _V4L2-BUF-CAP-SUPPORTS-DMABUF: + .. _V4L2-BUF-CAP-SUPPORTS-REQUESTS: ++.. _V4L2-BUF-CAP-SUPPORTS-ORPHANED-BUFS: + + .. cssclass:: longtable + +@@ -132,6 +138,11 @@ any DMA in progress, an implicit + * - ``V4L2_BUF_CAP_SUPPORTS_REQUESTS`` + - 0x00000008 + - This buffer type supports :ref:`requests <media-request-api>`. ++ * - ``V4L2_BUF_CAP_SUPPORTS_ORPHANED_BUFS`` ++ - 0x00000010 ++ - The kernel allows calling :ref:`VIDIOC_REQBUFS` while buffers are still ++ mapped or exported via DMABUF. These orphaned buffers will be freed ++ when they are unmapped or when the exported DMABUF fds are closed. + + Return Value + ============ +--- a/drivers/media/common/videobuf2/videobuf2-core.c ++++ b/drivers/media/common/videobuf2/videobuf2-core.c +@@ -684,11 +684,9 @@ int vb2_core_reqbufs(struct vb2_queue *q + * are not in use and can be freed. + */ + mutex_lock(&q->mmap_lock); +- if (q->memory == VB2_MEMORY_MMAP && __buffers_in_use(q)) { +- mutex_unlock(&q->mmap_lock); +- dprintk(1, "memory in use, cannot free\n"); +- return -EBUSY; +- } ++ if (debug && q->memory == VB2_MEMORY_MMAP && ++ __buffers_in_use(q)) ++ dprintk(1, "memory in use, orphaning buffers\n"); + + /* + * Call queue_cancel to clean up any buffers in the PREPARED or +--- a/drivers/media/common/videobuf2/videobuf2-v4l2.c ++++ b/drivers/media/common/videobuf2/videobuf2-v4l2.c +@@ -484,7 +484,7 @@ EXPORT_SYMBOL(vb2_querybuf); + + static void fill_buf_caps(struct vb2_queue *q, u32 *caps) + { +- *caps = 0; ++ *caps = V4L2_BUF_CAP_SUPPORTS_ORPHANED_BUFS; + if (q->io_modes & VB2_MMAP) + *caps |= V4L2_BUF_CAP_SUPPORTS_MMAP; + if (q->io_modes & VB2_USERPTR) +--- a/include/uapi/linux/videodev2.h ++++ b/include/uapi/linux/videodev2.h +@@ -881,6 +881,7 @@ struct v4l2_requestbuffers { + #define V4L2_BUF_CAP_SUPPORTS_USERPTR (1 << 1) + #define V4L2_BUF_CAP_SUPPORTS_DMABUF (1 << 2) + #define V4L2_BUF_CAP_SUPPORTS_REQUESTS (1 << 3) ++#define V4L2_BUF_CAP_SUPPORTS_ORPHANED_BUFS (1 << 4) + + /** + * struct v4l2_plane - plane info for multi-planar buffers |