Messages in this thread | | | Date | Mon, 3 Jul 2023 19:06:40 +0800 | Subject | Re: [PATCH v3 10/11] media: v4l2: Add DELETE_BUF ioctl | From | Hsia-Jun Li <> |
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Sorry for html version, again.
On 7/3/23 18:35, Benjamin Gaignard wrote: > CAUTION: Email originated externally, do not click links or open > attachments unless you recognize the sender and know the content is safe. > > > Le 03/07/2023 à 11:20, Hsia-Jun Li a écrit : >> >> On 7/3/23 16:52, Benjamin Gaignard wrote: >>> CAUTION: Email originated externally, do not click links or open >>> attachments unless you recognize the sender and know the content is >>> safe. >>> >>> >>> Le 03/07/2023 à 10:19, Hsia-Jun Li a écrit : >>>> >>>> On 7/3/23 16:12, Benjamin Gaignard wrote: >>>>> CAUTION: Email originated externally, do not click links or open >>>>> attachments unless you recognize the sender and know the content is >>>>> safe. >>>>> >>>>> >>>>> Le 30/06/2023 à 11:43, Hsia-Jun Li a écrit : >>>>>> >>>>>> On 6/27/23 16:47, Hsia-Jun Li wrote: >>>>>>> CAUTION: Email originated externally, do not click links or open >>>>>>> attachments unless you recognize the sender and know the content is >>>>>>> safe. >>>>>>> >>>>>>> >>>>>>> On 6/27/23 16:43, Benjamin Gaignard wrote: >>>>>>>> CAUTION: Email originated externally, do not click links or open >>>>>>>> attachments unless you recognize the sender and know the >>>>>>>> content is >>>>>>>> safe. >>>>>>>> >>>>>>>> >>>>>>>> Le 27/06/2023 à 09:30, Hsia-Jun Li a écrit : >>>>>>>>> >>>>>>>>> On 6/22/23 21:13, Benjamin Gaignard wrote: >>>>>>>>>> CAUTION: Email originated externally, do not click links or open >>>>>>>>>> attachments unless you recognize the sender and know the >>>>>>>>>> content is >>>>>>>>>> safe. >>>>>>>>>> >>>>>>>>>> >>>>>>>>>> VIDIOC_DELETE_BUF ioctl allows to delete a buffer from a queue. >>>>>>>>>> >>>>>>>>>> Signed-off-by: Benjamin Gaignard >>>>>>>>>> <benjamin.gaignard@collabora.com> >>>>>>>>>> --- >>>>>>>>>> .../userspace-api/media/v4l/user-func.rst | 1 + >>>>>>>>>> .../media/v4l/vidioc-delete-buf.rst | 51 >>>>>>>>>> +++++++++++++++++++ >>>>>>>>>> .../media/common/videobuf2/videobuf2-core.c | 33 ++++++++++++ >>>>>>>>>> .../media/common/videobuf2/videobuf2-v4l2.c | 6 +++ >>>>>>>>>> drivers/media/v4l2-core/v4l2-dev.c | 1 + >>>>>>>>>> drivers/media/v4l2-core/v4l2-ioctl.c | 10 ++++ >>>>>>>>>> include/media/v4l2-ioctl.h | 4 ++ >>>>>>>>>> include/media/videobuf2-core.h | 9 ++++ >>>>>>>>>> include/media/videobuf2-v4l2.h | 11 ++++ >>>>>>>>>> include/uapi/linux/videodev2.h | 2 + >>>>>>>>>> 10 files changed, 128 insertions(+) >>>>>>>>>> create mode 100644 >>>>>>>>>> Documentation/userspace-api/media/v4l/vidioc-delete-buf.rst >>>>>>>>>> >>>>>>>>>> diff --git a/Documentation/userspace-api/media/v4l/user-func.rst >>>>>>>>>> b/Documentation/userspace-api/media/v4l/user-func.rst >>>>>>>>>> index 15ff0bf7bbe6..8c74016e12fd 100644 >>>>>>>>>> --- a/Documentation/userspace-api/media/v4l/user-func.rst >>>>>>>>>> +++ b/Documentation/userspace-api/media/v4l/user-func.rst >>>>>>>>>> @@ -17,6 +17,7 @@ Function Reference >>>>>>>>>> vidioc-dbg-g-chip-info >>>>>>>>>> vidioc-dbg-g-register >>>>>>>>>> vidioc-decoder-cmd >>>>>>>>>> + vidioc-delete-buf >>>>>>>>>> vidioc-dqevent >>>>>>>>>> vidioc-dv-timings-cap >>>>>>>>>> vidioc-encoder-cmd >>>>>>>>>> diff --git >>>>>>>>>> a/Documentation/userspace-api/media/v4l/vidioc-delete-buf.rst >>>>>>>>>> b/Documentation/userspace-api/media/v4l/vidioc-delete-buf.rst >>>>>>>>>> new file mode 100644 >>>>>>>>>> index 000000000000..0e7ce58f91bc >>>>>>>>>> --- /dev/null >>>>>>>>>> +++ >>>>>>>>>> b/Documentation/userspace-api/media/v4l/vidioc-delete-buf.rst >>>>>>>>>> @@ -0,0 +1,51 @@ >>>>>>>>>> +.. SPDX-License-Identifier: GFDL-1.1-no-invariants-or-later >>>>>>>>>> +.. c:namespace:: V4L >>>>>>>>>> + >>>>>>>>>> +.. _VIDIOC_DELETE_BUF: >>>>>>>>>> + >>>>>>>>>> +************************ >>>>>>>>>> +ioctl VIDIOC_DELETE_BUF >>>>>>>>>> +************************ >>>>>>>>>> + >>>>>>>>>> +Name >>>>>>>>>> +==== >>>>>>>>>> + >>>>>>>>>> +VIDIOC_DELETE_BUF - Delete a buffer from a queue >>>>>>>>>> + >>>>>>>>>> +Synopsis >>>>>>>>>> +======== >>>>>>>>>> + >>>>>>>>>> +.. c:macro:: VIDIOC_DELETE_BUF >>>>>>>>>> + >>>>>>>>>> +``int ioctl(int fd, VIDIOC_DELETE_BUF, struct v4l2_buffer >>>>>>>>>> *argp)`` >>>>>>>>>> + >>>>>>>>>> +Arguments >>>>>>>>>> +========= >>>>>>>>>> + >>>>>>>>>> +``fd`` >>>>>>>>>> + File descriptor returned by :c:func:`open()`. >>>>>>>>>> + >>>>>>>>>> +``argp`` >>>>>>>>>> + Pointer to struct :c:type:`v4l2_buffer`. >>>>>>>>>> + >>>>>>>>>> +Description >>>>>>>>>> +=========== >>>>>>>>>> + >>>>>>>>>> +Applications can optionally call the :ref:`VIDIOC_DELETE_BUF` >>>>>>>>>> ioctl to >>>>>>>>>> +delete a buffer from a queue. >>>>>>>>>> + >>>>>>>>>> +The struct :c:type:`v4l2_buffer` structure is specified in >>>>>>>>>> +:ref:`buffer`. >>>>>>>>>> + >>>>>>>>>> +Return Value >>>>>>>>>> +============ >>>>>>>>>> + >>>>>>>>>> +On success 0 is returned, on error -1 and the ``errno`` >>>>>>>>>> variable is >>>>>>>>>> set >>>>>>>>>> +appropriately. The generic error codes are described at the >>>>>>>>>> +:ref:`Generic Error Codes <gen-errors>` chapter. >>>>>>>>>> + >>>>>>>>>> +EBUSY >>>>>>>>>> + File I/O is in progress. >>>>>>>>>> + >>>>>>>>>> +EINVAL >>>>>>>>>> + The buffer ``index`` doesn't exist in the queue. >>>>>>>>>> diff --git a/drivers/media/common/videobuf2/videobuf2-core.c >>>>>>>>>> b/drivers/media/common/videobuf2/videobuf2-core.c >>>>>>>>>> index 899783f67580..aa546c972c3d 100644 >>>>>>>>>> --- a/drivers/media/common/videobuf2/videobuf2-core.c >>>>>>>>>> +++ b/drivers/media/common/videobuf2/videobuf2-core.c >>>>>>>>>> @@ -1637,6 +1637,39 @@ int vb2_core_prepare_buf(struct vb2_queue >>>>>>>>>> *q, >>>>>>>>>> unsigned int index, void *pb) >>>>>>>>>> } >>>>>>>>>> EXPORT_SYMBOL_GPL(vb2_core_prepare_buf); >>>>>>>>>> >>>>>>>>>> +int vb2_core_delete_buf(struct vb2_queue *q, unsigned int >>>>>>>>>> index) >>>>>>>>>> +{ >>>>>>>>>> + struct vb2_buffer *vb; >>>>>>>>>> + >>>>>>>>>> + vb = vb2_get_buffer(q, index); >>>>>>>>>> + if (!vb) { >>>>>>>>>> + dprintk(q, 1, "invalid buffer index %d\n", >>>>>>>>>> index); >>>>>>>>>> + return -EINVAL; >>>>>>>>>> + } >>>>>>>>>> + >>>>>>>>>> + if (vb->state != VB2_BUF_STATE_DEQUEUED) { >>>>>>>>>> + dprintk(q, 1, "can't delete non dequeued buffer >>>>>>>>>> index >>>>>>>>>> %d\n", index); >>>>>>>>>> + return -EINVAL; >>>>>>>>>> + } >>>>>>>>>> + >>>>>>>>> I know the driver could implement its own >>>>>>>>> v4l2_ioctl_ops->vidioc_delete_buf() that check whether a >>>>>>>>> buffer is >>>>>>>>> used by the hardware as a future reference frame. >>>>>>>>> But I think we need a flag to let the user know which buffer is >>>>>>>>> still >>>>>>>>> used by the hardware. >>>>>>>>> Alternative ref case is safe, we only know it's existing when >>>>>>>>> it is >>>>>>>>> dequeued in current V4L2 buffer mechanism. >>>>>>>>> While the Golden reference frame, such long term reference frame >>>>>>>>> could >>>>>>>>> last much longer. >>>>>>>> >>>>>>>> It is up to userland stack to know frames life time, it got the >>>>>>>> information for that. >>>>>>> >>>>>>> That is true for the stateless codec driver. >>>>>>> >>>>>>> While application for stateful decoder could never do that. It also >>>>>>> breaks what the document said: >>>>>>> >>>>>>> "The backing memory of |CAPTURE| buffers that are used as reference >>>>>>> frames by the stream may be read by the hardware even after they >>>>>>> are >>>>>>> dequeued. Consequently, the client should avoid writing into this >>>>>>> memory >>>>>>> while the |CAPTURE| queue is streaming. Failure to observe this may >>>>>>> result in corruption of decoded frames." >>>>>>> >>>>>>>> >>>>>>>>>> + if (vb->planes[0].mem_priv) >>>>>>>>>> + call_void_vb_qop(vb, buf_cleanup, vb); >>>>>>>>>> + >>>>>>>>>> + /* Free MMAP buffers or release USERPTR buffers */ >>>>>>>>>> + if (q->memory == VB2_MEMORY_MMAP) >>>>>>>>>> + __vb2_buf_mem_free(vb); >>>>>> >>>>>> Here is another problem for the existing application, the mmap() >>>>>> from >>>>>> the mmap offset or exportbuffer fd would not create a reference to >>>>>> buffer in this step(while the exportbuffer would create one itself). >>>>>> >>>>>> When you delete a buffer, you may not release it from its virtual >>>>>> memory space, leaving a corrupted virtual memory space. Also this >>>>>> behavior is right, because mmap(2) says: >>>>>> >>>>>> "After the mmap() call has returned, the file descriptor, fd, can >>>>>> be closed immediately without invalidating the map‐ping." >>>>> >>>>> Existing applications do not call DELETE_BUF ioctl and when call it >>>>> they will be aware that the buffer is removed. >>>>> I have done it in GStreamer: >>>>> https://urldefense.proofpoint.com/v2/url?u=https-3A__gitlab.freedesktop.org_benjamin.gaignard1_gstreamer_-2D_commit_fca0fbc934f4440693ce0ff6c8dc8a2e5f5f17d9&d=DwIDaQ&c=7dfBJ8cXbWjhc0BhImu8wVIoUFmBzj1s88r8EGyM0UY&r=P4xb2_7biqBxD4LGGPrSV6j-jf3C3xlR7PXU-mLTeZE&m=TGH9toTzGRfO5aBsfaMvGbcOw-28q6cPmpX6vScbHjpCtaLtb-RuvBvsJ0z9RvAB&s=Ufl1ccfRZf2EhnfCBvnQzRJV9CDhGxl5spe9WNECspU&e= >>>>> >>>>> >>>>> >>>> >>>> I have read that. >>>> >>>> There is not a VP8 parser in Gstreamer, while a parser would not work >>>> when deal with the secure video(userspace can't access the data >>>> context at all). >>>> >>>> Besides, this adds extra work for the application for a stateful codec >>>> driver. The application need to parser the bitstream and track the >>>> dpb. >>>> >>>> I don't mind if you could fix the nonfiction mechanism for those >>>> non-display frame and internal reference state. >>>> >>>> That could be requirement for codec firmware that its driver could >>>> support this DELETE_BUF ioctl() feature. >>> >>> Sorry I don't see the link with my patches here... >>> I have work on non-secure VP9 on stateless codec. >>> DELETE_BUF ioctl is optional and the main goal is to offer a way to >>> applications >>> to save memory if they know when they could delete buffers without >>> risk. >> >> I try to explain why I think this design in not "complete". One >> problem resolved, more problems would occur. >> >> >> For non-secure video, those applications have worked: >> >> - It would break what stateful means here, application need to >> acquire(parse) the information that driver should offer. >> >> Or it would break the decoding model. >> >> - Your Gstreamer sample code or this design won't work for AV1. > why ?
A frame in AV1 could be put to display order with a future frame. That is quite different to those ITU codecs.
Supposing a frame (we call it frame 0) without show_display frame, you could delete it (just want to do that) once it is decoded.
Actually, unless 7 future frames have came and parser has acknowledged them, it is not safe to delete that frame.
Or a show_exist that make frame 0 present.
In my personal opinion, this feature could break many uAPI's, I have said my worrying in the other emails. >> >> For all the future possible secure video: >> >> - This feature could never be used from the current design. >> >> >>> >>>> >>>>> >>>>> Regards, >>>>> Benjamin >>>>> >>>>>> >>>>>>>>>> + else if (q->memory == VB2_MEMORY_DMABUF) >>>>>>>>>> + __vb2_buf_dmabuf_put(vb); >>>>>>>>>> + else >>>>>>>>>> + __vb2_buf_userptr_put(vb); >>>>>>>>>> + >>>>>>>>>> + vb2_queue_remove_buffer(q, vb); >>>>>>>>>> + kfree(vb); >>>>>>>>>> + >>>>>>>>>> + dprintk(q, 2, "buffer %d deleted\n", index); >>>>>>>>>> + return 0; >>>>>>>>>> +} >>>>>>>>>> + >>>>>>>>>> /* >>>>>>>>>> * vb2_start_streaming() - Attempt to start streaming. >>>>>>>>>> * @q: videobuf2 queue >>>>>>>>>> diff --git a/drivers/media/common/videobuf2/videobuf2-v4l2.c >>>>>>>>>> b/drivers/media/common/videobuf2/videobuf2-v4l2.c >>>>>>>>>> index 724135d41f7f..cea666c17b41 100644 >>>>>>>>>> --- a/drivers/media/common/videobuf2/videobuf2-v4l2.c >>>>>>>>>> +++ b/drivers/media/common/videobuf2/videobuf2-v4l2.c >>>>>>>>>> @@ -751,6 +751,12 @@ int vb2_prepare_buf(struct vb2_queue *q, >>>>>>>>>> struct >>>>>>>>>> media_device *mdev, >>>>>>>>>> } >>>>>>>>>> EXPORT_SYMBOL_GPL(vb2_prepare_buf); >>>>>>>>>> >>>>>>>>>> +int vb2_delete_buf(struct vb2_queue *q, struct v4l2_buffer *b) >>>>>>>>>> +{ >>>>>>>>>> + return vb2_core_delete_buf(q, b->index); >>>>>>>>>> +} >>>>>>>>>> +EXPORT_SYMBOL_GPL(vb2_delete_buf); >>>>>>>>>> + >>>>>>>>>> int vb2_create_bufs(struct vb2_queue *q, struct >>>>>>>>>> v4l2_create_buffers >>>>>>>>>> *create) >>>>>>>>>> { >>>>>>>>>> unsigned requested_planes = 1; >>>>>>>>>> diff --git a/drivers/media/v4l2-core/v4l2-dev.c >>>>>>>>>> b/drivers/media/v4l2-core/v4l2-dev.c >>>>>>>>>> index f81279492682..80ace2e1e932 100644 >>>>>>>>>> --- a/drivers/media/v4l2-core/v4l2-dev.c >>>>>>>>>> +++ b/drivers/media/v4l2-core/v4l2-dev.c >>>>>>>>>> @@ -720,6 +720,7 @@ static void determine_valid_ioctls(struct >>>>>>>>>> video_device *vdev) >>>>>>>>>> SET_VALID_IOCTL(ops, VIDIOC_PREPARE_BUF, >>>>>>>>>> vidioc_prepare_buf); >>>>>>>>>> SET_VALID_IOCTL(ops, VIDIOC_STREAMON, >>>>>>>>>> vidioc_streamon); >>>>>>>>>> SET_VALID_IOCTL(ops, VIDIOC_STREAMOFF, >>>>>>>>>> vidioc_streamoff); >>>>>>>>>> + SET_VALID_IOCTL(ops, VIDIOC_DELETE_BUF, >>>>>>>>>> vidioc_delete_buf); >>>>>>>>>> } >>>>>>>>>> >>>>>>>>>> if (is_vid || is_vbi || is_meta) { >>>>>>>>>> diff --git a/drivers/media/v4l2-core/v4l2-ioctl.c >>>>>>>>>> b/drivers/media/v4l2-core/v4l2-ioctl.c >>>>>>>>>> index a858acea6547..1c737279d3ef 100644 >>>>>>>>>> --- a/drivers/media/v4l2-core/v4l2-ioctl.c >>>>>>>>>> +++ b/drivers/media/v4l2-core/v4l2-ioctl.c >>>>>>>>>> @@ -2156,6 +2156,15 @@ static int v4l_prepare_buf(const struct >>>>>>>>>> v4l2_ioctl_ops *ops, >>>>>>>>>> return ret ? ret : ops->vidioc_prepare_buf(file, fh, >>>>>>>>>> b); >>>>>>>>>> } >>>>>>>>>> >>>>>>>>>> +static int v4l_delete_buf(const struct v4l2_ioctl_ops *ops, >>>>>>>>>> + struct file *file, void *fh, void >>>>>>>>>> *arg) >>>>>>>>>> +{ >>>>>>>>>> + struct v4l2_buffer *b = arg; >>>>>>>>>> + int ret = check_fmt(file, b->type); >>>>>>>>>> + >>>>>>>>>> + return ret ? ret : ops->vidioc_delete_buf(file, fh, b); >>>>>>>>>> +} >>>>>>>>>> + >>>>>>>>>> static int v4l_g_parm(const struct v4l2_ioctl_ops *ops, >>>>>>>>>> struct file *file, void *fh, >>>>>>>>>> void >>>>>>>>>> *arg) >>>>>>>>>> { >>>>>>>>>> @@ -2905,6 +2914,7 @@ static const struct v4l2_ioctl_info >>>>>>>>>> v4l2_ioctls[] = { >>>>>>>>>> IOCTL_INFO(VIDIOC_ENUM_FREQ_BANDS, v4l_enum_freq_bands, >>>>>>>>>> v4l_print_freq_band, 0), >>>>>>>>>> IOCTL_INFO(VIDIOC_DBG_G_CHIP_INFO, v4l_dbg_g_chip_info, >>>>>>>>>> v4l_print_dbg_chip_info, INFO_FL_CLEAR(v4l2_dbg_chip_info, >>>>>>>>>> match)), >>>>>>>>>> IOCTL_INFO(VIDIOC_QUERY_EXT_CTRL, v4l_query_ext_ctrl, >>>>>>>>>> v4l_print_query_ext_ctrl, INFO_FL_CTRL | >>>>>>>>>> INFO_FL_CLEAR(v4l2_query_ext_ctrl, id)), >>>>>>>>>> + IOCTL_INFO(VIDIOC_DELETE_BUF, v4l_delete_buf, >>>>>>>>>> v4l_print_buffer, INFO_FL_QUEUE), >>>>>>>>>> }; >>>>>>>>>> #define V4L2_IOCTLS ARRAY_SIZE(v4l2_ioctls) >>>>>>>>>> >>>>>>>>>> diff --git a/include/media/v4l2-ioctl.h >>>>>>>>>> b/include/media/v4l2-ioctl.h >>>>>>>>>> index edb733f21604..2f232ed884c7 100644 >>>>>>>>>> --- a/include/media/v4l2-ioctl.h >>>>>>>>>> +++ b/include/media/v4l2-ioctl.h >>>>>>>>>> @@ -163,6 +163,8 @@ struct v4l2_fh; >>>>>>>>>> * :ref:`VIDIOC_CREATE_BUFS <vidioc_create_bufs>` ioctl >>>>>>>>>> * @vidioc_prepare_buf: pointer to the function that >>>>>>>>>> implements >>>>>>>>>> * :ref:`VIDIOC_PREPARE_BUF <vidioc_prepare_buf>` ioctl >>>>>>>>>> + * @vidioc_delete_buf: pointer to the function that implements >>>>>>>>>> + * :ref:`VIDIOC_DELETE_BUF <vidioc_delete_buf>` ioctl >>>>>>>>>> * @vidioc_overlay: pointer to the function that implements >>>>>>>>>> * :ref:`VIDIOC_OVERLAY <vidioc_overlay>` ioctl >>>>>>>>>> * @vidioc_g_fbuf: pointer to the function that implements >>>>>>>>>> @@ -422,6 +424,8 @@ struct v4l2_ioctl_ops { >>>>>>>>>> struct v4l2_create_buffers >>>>>>>>>> *b); >>>>>>>>>> int (*vidioc_prepare_buf)(struct file *file, void *fh, >>>>>>>>>> struct v4l2_buffer *b); >>>>>>>>>> + int (*vidioc_delete_buf)(struct file *file, void *fh, >>>>>>>>>> + struct v4l2_buffer *b); >>>>>>>>>> >>>>>>>>>> int (*vidioc_overlay)(struct file *file, void *fh, >>>>>>>>>> unsigned >>>>>>>>>> int i); >>>>>>>>>> int (*vidioc_g_fbuf)(struct file *file, void *fh, >>>>>>>>>> diff --git a/include/media/videobuf2-core.h >>>>>>>>>> b/include/media/videobuf2-core.h >>>>>>>>>> index 080b783d608d..0f9e68f76b77 100644 >>>>>>>>>> --- a/include/media/videobuf2-core.h >>>>>>>>>> +++ b/include/media/videobuf2-core.h >>>>>>>>>> @@ -840,6 +840,15 @@ int vb2_core_create_bufs(struct vb2_queue >>>>>>>>>> *q, >>>>>>>>>> enum vb2_memory memory, >>>>>>>>>> */ >>>>>>>>>> int vb2_core_prepare_buf(struct vb2_queue *q, unsigned int >>>>>>>>>> index, >>>>>>>>>> void *pb); >>>>>>>>>> >>>>>>>>>> +/** >>>>>>>>>> + * vb2_core_delete_buf() - >>>>>>>>>> + * @q: pointer to &struct vb2_queue with videobuf2 queue. >>>>>>>>>> + * @index: id number of the buffer. >>>>>>>>>> + * >>>>>>>>>> + * Return: returns zero on success; an error code otherwise. >>>>>>>>>> + */ >>>>>>>>>> +int vb2_core_delete_buf(struct vb2_queue *q, unsigned int >>>>>>>>>> index); >>>>>>>>>> + >>>>>>>>>> /** >>>>>>>>>> * vb2_core_qbuf() - Queue a buffer from userspace >>>>>>>>>> * >>>>>>>>>> diff --git a/include/media/videobuf2-v4l2.h >>>>>>>>>> b/include/media/videobuf2-v4l2.h >>>>>>>>>> index 88a7a565170e..3beeb4c735f0 100644 >>>>>>>>>> --- a/include/media/videobuf2-v4l2.h >>>>>>>>>> +++ b/include/media/videobuf2-v4l2.h >>>>>>>>>> @@ -114,6 +114,17 @@ int vb2_create_bufs(struct vb2_queue *q, >>>>>>>>>> struct >>>>>>>>>> v4l2_create_buffers *create); >>>>>>>>>> */ >>>>>>>>>> int vb2_prepare_buf(struct vb2_queue *q, struct media_device >>>>>>>>>> *mdev, >>>>>>>>>> struct v4l2_buffer *b); >>>>>>>>>> +/** >>>>>>>>>> + * vb2_delete_buf() - Delete the buffer from the queue >>>>>>>>>> + * >>>>>>>>>> + * @q: pointer to &struct vb2_queue with videobuf2 >>>>>>>>>> queue. >>>>>>>>>> + * @b: buffer structure passed from userspace to >>>>>>>>>> + * &v4l2_ioctl_ops->vidioc_delete_buf handler in driver >>>>>>>>>> + * >>>>>>>>>> + * The return values from this function are intended to be >>>>>>>>>> directly >>>>>>>>>> returned >>>>>>>>>> + * from &v4l2_ioctl_ops->vidioc_delete_buf handler in driver. >>>>>>>>>> + */ >>>>>>>>>> +int vb2_delete_buf(struct vb2_queue *q, struct v4l2_buffer *b); >>>>>>>>>> >>>>>>>>>> /** >>>>>>>>>> * vb2_qbuf() - Queue a buffer from userspace >>>>>>>>>> diff --git a/include/uapi/linux/videodev2.h >>>>>>>>>> b/include/uapi/linux/videodev2.h >>>>>>>>>> index aee75eb9e686..31bba1915642 100644 >>>>>>>>>> --- a/include/uapi/linux/videodev2.h >>>>>>>>>> +++ b/include/uapi/linux/videodev2.h >>>>>>>>>> @@ -2702,6 +2702,8 @@ struct v4l2_create_buffers { >>>>>>>>>> #define VIDIOC_DBG_G_CHIP_INFO _IOWR('V', 102, struct >>>>>>>>>> v4l2_dbg_chip_info) >>>>>>>>>> >>>>>>>>>> #define VIDIOC_QUERY_EXT_CTRL _IOWR('V', 103, struct >>>>>>>>>> v4l2_query_ext_ctrl) >>>>>>>>>> +#define VIDIOC_DELETE_BUF _IOWR('V', 104, struct >>>>>>>>>> v4l2_buffer) >>>>>>>>>> + >>>>>>>>>> >>>>>>>>>> /* Reminder: when adding new ioctls please add support for >>>>>>>>>> them to >>>>>>>>>> drivers/media/v4l2-core/v4l2-compat-ioctl32.c as well! */ >>>>>>>>>> -- >>>>>>>>>> 2.39.2 >>>>>>>>>> >>>>>>> -- >>>>>>> Hsia-Jun(Randy) Li >>>>>>> -- Hsia-Jun(Randy) Li
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