target/linux/bcm27xx/patches-4.19/950-0243-media-videobuf2-Allow-exporting-of-a-struct-dmabuf.patch

   1 From 0b2a62596d0e6efe17bb87a3a5ebd91cee60c64b Mon Sep 17 00:00:00 2001
   2 From: Dave Stevenson <dave.stevenson@raspberrypi.org>
   3 Date: Mon, 29 Oct 2018 17:57:45 +0000
   4 Subject: [PATCH] media: videobuf2: Allow exporting of a struct dmabuf
   5
   6 videobuf2 only allowed exporting a dmabuf as a file descriptor,
   7 but there are instances where having the struct dma_buf is
   8 useful within the kernel.
   9
  10 Split the current implementation into two, one step which
  11 exports a struct dma_buf, and the second which converts that
  12 into an fd.
  13
  14 Signed-off-by: Dave Stevenson <dave.stevenson@raspberrypi.org>
  15 ---
  16  .../media/common/videobuf2/videobuf2-core.c   | 21 ++++++++++++++++---
  17  include/media/videobuf2-core.h                | 15 +++++++++++++
  18  2 files changed, 33 insertions(+), 3 deletions(-)
  19
  20 --- a/drivers/media/common/videobuf2/videobuf2-core.c
  21 +++ b/drivers/media/common/videobuf2/videobuf2-core.c
  22 @@ -1851,12 +1851,12 @@ static int __find_plane_by_offset(struct
  23         return -EINVAL;
  24  }
  25
  26 -int vb2_core_expbuf(struct vb2_queue *q, int *fd, unsigned int type,
  27 -               unsigned int index, unsigned int plane, unsigned int flags)
  28 +int vb2_core_expbuf_dmabuf(struct vb2_queue *q, unsigned int type,
  29 +                          unsigned int index, unsigned int plane,
  30 +                          unsigned int flags, struct dma_buf **dmabuf)
  31  {
  32         struct vb2_buffer *vb = NULL;
  33         struct vb2_plane *vb_plane;
  34 -       int ret;
  35         struct dma_buf *dbuf;
  36
  37         if (q->memory != VB2_MEMORY_MMAP) {
  38 @@ -1906,6 +1906,21 @@ int vb2_core_expbuf(struct vb2_queue *q,
  39                 return -EINVAL;
  40         }
  41
  42 +       *dmabuf = dbuf;
  43 +       return 0;
  44 +}
  45 +EXPORT_SYMBOL_GPL(vb2_core_expbuf_dmabuf);
  46 +
  47 +int vb2_core_expbuf(struct vb2_queue *q, int *fd, unsigned int type,
  48 +                   unsigned int index, unsigned int plane, unsigned int flags)
  49 +{
  50 +       struct dma_buf *dbuf;
  51 +       int ret;
  52 +
  53 +       ret = vb2_core_expbuf_dmabuf(q, type, index, plane, flags, &dbuf);
  54 +       if (ret)
  55 +               return ret;
  56 +
  57         ret = dma_buf_fd(dbuf, flags & ~O_ACCMODE);
  58         if (ret < 0) {
  59                 dprintk(3, "buffer %d, plane %d failed to export (%d)\n",
  60 --- a/include/media/videobuf2-core.h
  61 +++ b/include/media/videobuf2-core.h
  62 @@ -825,6 +825,21 @@ int vb2_core_streamon(struct vb2_queue *
  63  int vb2_core_streamoff(struct vb2_queue *q, unsigned int type);
  64
  65  /**
  66 + * vb2_core_expbuf_dmabuf() - Export a buffer as a dma_buf structure
  67 + * @q:         videobuf2 queue
  68 + * @type:      buffer type
  69 + * @index:     id number of the buffer
  70 + * @plane:     index of the plane to be exported, 0 for single plane queues
  71 + * @flags:     flags for newly created file, currently only O_CLOEXEC is
  72 + *             supported, refer to manual of open syscall for more details
  73 + * @dmabuf:    Returns the dmabuf pointer
  74 + *
  75 + */
  76 +int vb2_core_expbuf_dmabuf(struct vb2_queue *q, unsigned int type,
  77 +                          unsigned int index, unsigned int plane,
  78 +                          unsigned int flags, struct dma_buf **dmabuf);
  79 +
  80 +/**
  81   * vb2_core_expbuf() - Export a buffer as a file descriptor.
  82   * @q:         pointer to &struct vb2_queue with videobuf2 queue.
  83   * @fd:                pointer to the file descriptor associated with DMABUF