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Diffstat (limited to 'drivers/media/common/videobuf2/videobuf2-dma-contig.c')
-rw-r--r--drivers/media/common/videobuf2/videobuf2-dma-contig.c31
1 files changed, 16 insertions, 15 deletions
diff --git a/drivers/media/common/videobuf2/videobuf2-dma-contig.c b/drivers/media/common/videobuf2/videobuf2-dma-contig.c
index 7d77e4d30c8a..d0c9dffe49e5 100644
--- a/drivers/media/common/videobuf2/videobuf2-dma-contig.c
+++ b/drivers/media/common/videobuf2/videobuf2-dma-contig.c
@@ -267,8 +267,14 @@ static void vb2_dc_dmabuf_ops_detach(struct dma_buf *dbuf,
/* release the scatterlist cache */
if (attach->dma_dir != DMA_NONE)
- dma_unmap_sg(db_attach->dev, sgt->sgl, sgt->orig_nents,
- attach->dma_dir);
+ /*
+ * Cache sync can be skipped here, as the vb2_dc memory is
+ * allocated from device coherent memory, which means the
+ * memory locations do not require any explicit cache
+ * maintenance prior or after being used by the device.
+ */
+ dma_unmap_sg_attrs(db_attach->dev, sgt->sgl, sgt->orig_nents,
+ attach->dma_dir, DMA_ATTR_SKIP_CPU_SYNC);
sg_free_table(sgt);
kfree(attach);
db_attach->priv = NULL;
@@ -293,14 +299,17 @@ static struct sg_table *vb2_dc_dmabuf_ops_map(
/* release any previous cache */
if (attach->dma_dir != DMA_NONE) {
- dma_unmap_sg(db_attach->dev, sgt->sgl, sgt->orig_nents,
- attach->dma_dir);
+ dma_unmap_sg_attrs(db_attach->dev, sgt->sgl, sgt->orig_nents,
+ attach->dma_dir, DMA_ATTR_SKIP_CPU_SYNC);
attach->dma_dir = DMA_NONE;
}
- /* mapping to the client with new direction */
- sgt->nents = dma_map_sg(db_attach->dev, sgt->sgl, sgt->orig_nents,
- dma_dir);
+ /*
+ * mapping to the client with new direction, no cache sync
+ * required see comment in vb2_dc_dmabuf_ops_detach()
+ */
+ sgt->nents = dma_map_sg_attrs(db_attach->dev, sgt->sgl, sgt->orig_nents,
+ dma_dir, DMA_ATTR_SKIP_CPU_SYNC);
if (!sgt->nents) {
pr_err("failed to map scatterlist\n");
mutex_unlock(lock);
@@ -326,13 +335,6 @@ static void vb2_dc_dmabuf_ops_release(struct dma_buf *dbuf)
vb2_dc_put(dbuf->priv);
}
-static void *vb2_dc_dmabuf_ops_kmap(struct dma_buf *dbuf, unsigned long pgnum)
-{
- struct vb2_dc_buf *buf = dbuf->priv;
-
- return buf->vaddr ? buf->vaddr + pgnum * PAGE_SIZE : NULL;
-}
-
static void *vb2_dc_dmabuf_ops_vmap(struct dma_buf *dbuf)
{
struct vb2_dc_buf *buf = dbuf->priv;
@@ -351,7 +353,6 @@ static const struct dma_buf_ops vb2_dc_dmabuf_ops = {
.detach = vb2_dc_dmabuf_ops_detach,
.map_dma_buf = vb2_dc_dmabuf_ops_map,
.unmap_dma_buf = vb2_dc_dmabuf_ops_unmap,
- .map = vb2_dc_dmabuf_ops_kmap,
.vmap = vb2_dc_dmabuf_ops_vmap,
.mmap = vb2_dc_dmabuf_ops_mmap,
.release = vb2_dc_dmabuf_ops_release,
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