From ea3aba8482be6f3e4815f4014fa7302fc77c9c3f Mon Sep 17 00:00:00 2001 From: Philipp Zabel Date: Tue, 21 May 2013 05:11:35 -0300 Subject: [PATCH] [media] videobuf2: Add support for file access mode flags for DMABUF exporting Currently it is not possible for userspace to map a DMABUF exported buffer with write permissions. This patch allows to also pass O_RDONLY/O_RDWR when exporting the buffer, so that userspace may map it with write permissions. Signed-off-by: Philipp Zabel Signed-off-by: Sylwester Nawrocki Signed-off-by: Mauro Carvalho Chehab --- Documentation/DocBook/media/v4l/vidioc-expbuf.xml | 8 +++++--- drivers/media/v4l2-core/videobuf2-core.c | 8 ++++---- drivers/media/v4l2-core/videobuf2-dma-contig.c | 4 ++-- include/media/videobuf2-core.h | 2 +- 4 files changed, 12 insertions(+), 10 deletions(-) diff --git a/Documentation/DocBook/media/v4l/vidioc-expbuf.xml b/Documentation/DocBook/media/v4l/vidioc-expbuf.xml index e287c8fc803b..4165e7bfa4ff 100644 --- a/Documentation/DocBook/media/v4l/vidioc-expbuf.xml +++ b/Documentation/DocBook/media/v4l/vidioc-expbuf.xml @@ -73,7 +73,8 @@ range from zero to the maximal number of valid planes for the currently active format. For the single-planar API, applications must set plane to zero. Additional flags may be posted in the flags field. Refer to a manual for open() for details. -Currently only O_CLOEXEC is supported. All other fields must be set to zero. +Currently only O_CLOEXEC, O_RDONLY, O_WRONLY, and O_RDWR are supported. All +other fields must be set to zero. In the case of multi-planar API, every plane is exported separately using multiple VIDIOC_EXPBUF calls. @@ -170,8 +171,9 @@ multi-planar API. Otherwise this value must be set to zero. __u32 flags Flags for the newly created file, currently only -O_CLOEXEC is supported, refer to the manual of open() for more -details. +O_CLOEXEC , O_RDONLY, O_WRONLY +, and O_RDWR are supported, refer to the manual +of open() for more details. __s32 diff --git a/drivers/media/v4l2-core/videobuf2-core.c b/drivers/media/v4l2-core/videobuf2-core.c index b19b306c8f7f..57ba131f08ad 100644 --- a/drivers/media/v4l2-core/videobuf2-core.c +++ b/drivers/media/v4l2-core/videobuf2-core.c @@ -1824,8 +1824,8 @@ int vb2_expbuf(struct vb2_queue *q, struct v4l2_exportbuffer *eb) return -EINVAL; } - if (eb->flags & ~O_CLOEXEC) { - dprintk(1, "Queue does support only O_CLOEXEC flag\n"); + if (eb->flags & ~(O_CLOEXEC | O_ACCMODE)) { + dprintk(1, "Queue does support only O_CLOEXEC and access mode flags\n"); return -EINVAL; } @@ -1848,14 +1848,14 @@ int vb2_expbuf(struct vb2_queue *q, struct v4l2_exportbuffer *eb) vb_plane = &vb->planes[eb->plane]; - dbuf = call_memop(q, get_dmabuf, vb_plane->mem_priv); + dbuf = call_memop(q, get_dmabuf, vb_plane->mem_priv, eb->flags & O_ACCMODE); if (IS_ERR_OR_NULL(dbuf)) { dprintk(1, "Failed to export buffer %d, plane %d\n", eb->index, eb->plane); return -EINVAL; } - ret = dma_buf_fd(dbuf, eb->flags); + ret = dma_buf_fd(dbuf, eb->flags & ~O_ACCMODE); if (ret < 0) { dprintk(3, "buffer %d, plane %d failed to export (%d)\n", eb->index, eb->plane, ret); diff --git a/drivers/media/v4l2-core/videobuf2-dma-contig.c b/drivers/media/v4l2-core/videobuf2-dma-contig.c index 646f08f4f504..33d3871d1e13 100644 --- a/drivers/media/v4l2-core/videobuf2-dma-contig.c +++ b/drivers/media/v4l2-core/videobuf2-dma-contig.c @@ -393,7 +393,7 @@ static struct sg_table *vb2_dc_get_base_sgt(struct vb2_dc_buf *buf) return sgt; } -static struct dma_buf *vb2_dc_get_dmabuf(void *buf_priv) +static struct dma_buf *vb2_dc_get_dmabuf(void *buf_priv, unsigned long flags) { struct vb2_dc_buf *buf = buf_priv; struct dma_buf *dbuf; @@ -404,7 +404,7 @@ static struct dma_buf *vb2_dc_get_dmabuf(void *buf_priv) if (WARN_ON(!buf->sgt_base)) return NULL; - dbuf = dma_buf_export(buf, &vb2_dc_dmabuf_ops, buf->size, 0); + dbuf = dma_buf_export(buf, &vb2_dc_dmabuf_ops, buf->size, flags); if (IS_ERR(dbuf)) return NULL; diff --git a/include/media/videobuf2-core.h b/include/media/videobuf2-core.h index bd8218b15009..941055e9d125 100644 --- a/include/media/videobuf2-core.h +++ b/include/media/videobuf2-core.h @@ -83,7 +83,7 @@ struct vb2_fileio_data; struct vb2_mem_ops { void *(*alloc)(void *alloc_ctx, unsigned long size, gfp_t gfp_flags); void (*put)(void *buf_priv); - struct dma_buf *(*get_dmabuf)(void *buf_priv); + struct dma_buf *(*get_dmabuf)(void *buf_priv, unsigned long flags); void *(*get_userptr)(void *alloc_ctx, unsigned long vaddr, unsigned long size, int write); -- 2.30.2