media: videobuf2: move cache_hints handling to allocators

This moves cache hints handling from the videobuf2 core down
to the allocator's level, because allocators do the sync/flush
caches eventually and may take better decisions. Besides,
allocators already decide whether cache sync/flush should
be done or can be skipped. This patch moves the scattered
buffer cache sync logic to one common place.
Signed-off-by: Sergey Senozhatsky <senozhatsky@chromium.org>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>

drivers/media/common/videobuf2/videobuf2-core.c

@@ -328,9 +328,6 @@ static void __vb2_buf_mem_prepare(struct vb2_buffer *vb)
 		return;
 
 	vb->synced = 1;
-	if (vb->skip_cache_sync_on_prepare)
-		return;
-
 	for (plane = 0; plane < vb->num_planes; ++plane)
 		call_void_memop(vb, prepare, vb->planes[plane].mem_priv);
 }
@@ -347,9 +344,6 @@ static void __vb2_buf_mem_finish(struct vb2_buffer *vb)
 		return;
 
 	vb->synced = 0;
-	if (vb->skip_cache_sync_on_finish)
-		return;
-
 	for (plane = 0; plane < vb->num_planes; ++plane)
 		call_void_memop(vb, finish, vb->planes[plane].mem_priv);
 }

drivers/media/common/videobuf2/videobuf2-dma-contig.c

@@ -101,6 +101,9 @@ static void vb2_dc_prepare(void *buf_priv)
 	struct vb2_dc_buf *buf = buf_priv;
 	struct sg_table *sgt = buf->dma_sgt;
 
+	if (buf->vb->skip_cache_sync_on_prepare)
+		return;
+
 	if (!sgt)
 		return;
 
@@ -112,6 +115,9 @@ static void vb2_dc_finish(void *buf_priv)
 	struct vb2_dc_buf *buf = buf_priv;
 	struct sg_table *sgt = buf->dma_sgt;
 
+	if (buf->vb->skip_cache_sync_on_finish)
+		return;
+
 	if (!sgt)
 		return;
 

drivers/media/common/videobuf2/videobuf2-dma-sg.c

@@ -204,6 +204,9 @@ static void vb2_dma_sg_prepare(void *buf_priv)
 	struct vb2_dma_sg_buf *buf = buf_priv;
 	struct sg_table *sgt = buf->dma_sgt;
 
+	if (buf->vb->skip_cache_sync_on_prepare)
+		return;
+
 	dma_sync_sgtable_for_device(buf->dev, sgt, buf->dma_dir);
 }
 
@@ -212,6 +215,9 @@ static void vb2_dma_sg_finish(void *buf_priv)
 	struct vb2_dma_sg_buf *buf = buf_priv;
 	struct sg_table *sgt = buf->dma_sgt;
 
+	if (buf->vb->skip_cache_sync_on_finish)
+		return;
+
 	dma_sync_sgtable_for_cpu(buf->dev, sgt, buf->dma_dir);
 }