| Message ID | 20200204025641.218376-12-senozhatsky@chromium.org (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | Implement V4L2_BUF_FLAG_NO_CACHE_* flags | expand |
On 2/4/20 3:56 AM, Sergey Senozhatsky wrote: > Provide begin_cpu_access() and end_cpu_access() dma_buf_ops > callbacks for cache synchronisation on exported buffers. > > V4L2_FLAG_MEMORY_NON_CONSISTENT has no effect on dma-sg buffers. > dma-sg allocates memory using the page allocator directly, so > there is no memory consistency guarantee. This should also be a comment in the code. Regards, Hans > > Change-Id: Ia0d9d72a8c2a9fe3264ac148f59201573289ed2c > Signed-off-by: Sergey Senozhatsky <senozhatsky@chromium.org> > --- > .../media/common/videobuf2/videobuf2-dma-sg.c | 22 +++++++++++++++++++ > 1 file changed, 22 insertions(+) > > diff --git a/drivers/media/common/videobuf2/videobuf2-dma-sg.c b/drivers/media/common/videobuf2/videobuf2-dma-sg.c > index 6db60e9d5183..bfc99a0cb7b9 100644 > --- a/drivers/media/common/videobuf2/videobuf2-dma-sg.c > +++ b/drivers/media/common/videobuf2/videobuf2-dma-sg.c > @@ -470,6 +470,26 @@ static void vb2_dma_sg_dmabuf_ops_release(struct dma_buf *dbuf) > vb2_dma_sg_put(dbuf->priv); > } > > +static int vb2_dma_sg_dmabuf_ops_begin_cpu_access(struct dma_buf *dbuf, > + enum dma_data_direction direction) > +{ > + struct vb2_dma_sg_buf *buf = dbuf->priv; > + struct sg_table *sgt = buf->dma_sgt; > + > + dma_sync_sg_for_cpu(buf->dev, sgt->sgl, sgt->nents, buf->dma_dir); > + return 0; > +} > + > +static int vb2_dma_sg_dmabuf_ops_end_cpu_access(struct dma_buf *dbuf, > + enum dma_data_direction direction) > +{ > + struct vb2_dma_sg_buf *buf = dbuf->priv; > + struct sg_table *sgt = buf->dma_sgt; > + > + dma_sync_sg_for_device(buf->dev, sgt->sgl, sgt->nents, buf->dma_dir); > + return 0; > +} > + > static void *vb2_dma_sg_dmabuf_ops_vmap(struct dma_buf *dbuf) > { > struct vb2_dma_sg_buf *buf = dbuf->priv; > @@ -488,6 +508,8 @@ static const struct dma_buf_ops vb2_dma_sg_dmabuf_ops = { > .detach = vb2_dma_sg_dmabuf_ops_detach, > .map_dma_buf = vb2_dma_sg_dmabuf_ops_map, > .unmap_dma_buf = vb2_dma_sg_dmabuf_ops_unmap, > + .begin_cpu_access = vb2_dma_sg_dmabuf_ops_begin_cpu_access, > + .end_cpu_access = vb2_dma_sg_dmabuf_ops_end_cpu_access, > .vmap = vb2_dma_sg_dmabuf_ops_vmap, > .mmap = vb2_dma_sg_dmabuf_ops_mmap, > .release = vb2_dma_sg_dmabuf_ops_release, >
On (20/02/19 09:35), Hans Verkuil wrote: > On 2/4/20 3:56 AM, Sergey Senozhatsky wrote: > > Provide begin_cpu_access() and end_cpu_access() dma_buf_ops > > callbacks for cache synchronisation on exported buffers. > > > > V4L2_FLAG_MEMORY_NON_CONSISTENT has no effect on dma-sg buffers. > > dma-sg allocates memory using the page allocator directly, so > > there is no memory consistency guarantee. > > This should also be a comment in the code. OK. -ss
diff --git a/drivers/media/common/videobuf2/videobuf2-dma-sg.c b/drivers/media/common/videobuf2/videobuf2-dma-sg.c index 6db60e9d5183..bfc99a0cb7b9 100644 --- a/drivers/media/common/videobuf2/videobuf2-dma-sg.c +++ b/drivers/media/common/videobuf2/videobuf2-dma-sg.c @@ -470,6 +470,26 @@ static void vb2_dma_sg_dmabuf_ops_release(struct dma_buf *dbuf) vb2_dma_sg_put(dbuf->priv); } +static int vb2_dma_sg_dmabuf_ops_begin_cpu_access(struct dma_buf *dbuf, + enum dma_data_direction direction) +{ + struct vb2_dma_sg_buf *buf = dbuf->priv; + struct sg_table *sgt = buf->dma_sgt; + + dma_sync_sg_for_cpu(buf->dev, sgt->sgl, sgt->nents, buf->dma_dir); + return 0; +} + +static int vb2_dma_sg_dmabuf_ops_end_cpu_access(struct dma_buf *dbuf, + enum dma_data_direction direction) +{ + struct vb2_dma_sg_buf *buf = dbuf->priv; + struct sg_table *sgt = buf->dma_sgt; + + dma_sync_sg_for_device(buf->dev, sgt->sgl, sgt->nents, buf->dma_dir); + return 0; +} + static void *vb2_dma_sg_dmabuf_ops_vmap(struct dma_buf *dbuf) { struct vb2_dma_sg_buf *buf = dbuf->priv; @@ -488,6 +508,8 @@ static const struct dma_buf_ops vb2_dma_sg_dmabuf_ops = { .detach = vb2_dma_sg_dmabuf_ops_detach, .map_dma_buf = vb2_dma_sg_dmabuf_ops_map, .unmap_dma_buf = vb2_dma_sg_dmabuf_ops_unmap, + .begin_cpu_access = vb2_dma_sg_dmabuf_ops_begin_cpu_access, + .end_cpu_access = vb2_dma_sg_dmabuf_ops_end_cpu_access, .vmap = vb2_dma_sg_dmabuf_ops_vmap, .mmap = vb2_dma_sg_dmabuf_ops_mmap, .release = vb2_dma_sg_dmabuf_ops_release,
Provide begin_cpu_access() and end_cpu_access() dma_buf_ops callbacks for cache synchronisation on exported buffers. V4L2_FLAG_MEMORY_NON_CONSISTENT has no effect on dma-sg buffers. dma-sg allocates memory using the page allocator directly, so there is no memory consistency guarantee. Change-Id: Ia0d9d72a8c2a9fe3264ac148f59201573289ed2c Signed-off-by: Sergey Senozhatsky <senozhatsky@chromium.org> --- .../media/common/videobuf2/videobuf2-dma-sg.c | 22 +++++++++++++++++++ 1 file changed, 22 insertions(+)