Re: [PATCH v6 35/36] videobuf2: use sgtable-based scatterlist wrappers

Use recently introduced common wrappers operating directly on the struct
sg_table objects and scatterlist page iterators to make the code a bit
more compact, robust, easier to follow and copy/paste safe.

No functional change, because the code already properly did all the
scaterlist related calls.

Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
---
  .../common/videobuf2/videobuf2-dma-contig.c   | 41 ++++++++-----------
  .../media/common/videobuf2/videobuf2-dma-sg.c | 32 ++++++---------
  .../common/videobuf2/videobuf2-vmalloc.c      | 12 ++----
  3 files changed, 34 insertions(+), 51 deletions(-)

diff --git a/drivers/media/common/videobuf2/videobuf2-dma-contig.c b/drivers/media/common/videobuf2/videobuf2-dma-contig.c
index f4b4a7c135eb..ba01a8692d88 100644
--- a/drivers/media/common/videobuf2/videobuf2-dma-contig.c
+++ b/drivers/media/common/videobuf2/videobuf2-dma-contig.c

@@ -48,16 +48,15 @@ struct vb2_dc_buf {
  
  static unsigned long vb2_dc_get_contiguous_size(struct sg_table *sgt)
  {
-	struct scatterlist *s;
  	dma_addr_t expected = sg_dma_address(sgt->sgl);
-	unsigned int i;
+	struct sg_dma_page_iter dma_iter;
  	unsigned long size = 0;
  
-	for_each_sg(sgt->sgl, s, sgt->nents, i) {
-		if (sg_dma_address(s) != expected)
+	for_each_sgtable_dma_page(sgt, &dma_iter, 0) {
+		if (sg_page_iter_dma_address(&dma_iter) != expected)
  			break;
-		expected = sg_dma_address(s) + sg_dma_len(s);
-		size += sg_dma_len(s);
+		expected += PAGE_SIZE;
+		size += PAGE_SIZE;

diff --git a/drivers/media/common/videobuf2/videobuf2-dma-sg.c b/drivers/media/common/videobuf2/videobuf2-dma-sg.c
index 92072a08af25..6ddf953efa11 100644
--- a/drivers/media/common/videobuf2/videobuf2-dma-sg.c
+++ b/drivers/media/common/videobuf2/videobuf2-dma-sg.c

@@ -142,9 +142,8 @@ static void *vb2_dma_sg_alloc(struct device *dev, unsigned long dma_attrs,
  	 * No need to sync to the device, this will happen later when the
  	 * prepare() memop is called.
  	 */
-	sgt->nents = dma_map_sg_attrs(buf->dev, sgt->sgl, sgt->orig_nents,
-				      buf->dma_dir, DMA_ATTR_SKIP_CPU_SYNC);
-	if (!sgt->nents)
+	if (dma_map_sgtable(buf->dev, sgt, buf->dma_dir,
+			    DMA_ATTR_SKIP_CPU_SYNC)) {

  		goto fail_map;
  
  	buf->handler.refcount = &buf->refcount;

@@ -180,8 +179,8 @@ static void vb2_dma_sg_put(void *buf_priv)
  	if (refcount_dec_and_test(&buf->refcount)) {
  		dprintk(1, "%s: Freeing buffer of %d pages\n", __func__,
  			buf->num_pages);
-		dma_unmap_sg_attrs(buf->dev, sgt->sgl, sgt->orig_nents,
-				   buf->dma_dir, DMA_ATTR_SKIP_CPU_SYNC);
+		dma_unmap_sgtable(buf->dev, sgt, buf->dma_dir,
+				  DMA_ATTR_SKIP_CPU_SYNC);
  		if (buf->vaddr)
  			vm_unmap_ram(buf->vaddr, buf->num_pages);
  		sg_free_table(buf->dma_sgt);

@@ -202,8 +201,7 @@ static void vb2_dma_sg_prepare(void *buf_priv)
  	if (buf->db_attach)
  		return;
  
-	dma_sync_sg_for_device(buf->dev, sgt->sgl, sgt->orig_nents,
-			       buf->dma_dir);
+	dma_sync_sgtable_for_device(buf->dev, sgt, buf->dma_dir);
  }
  
  static void vb2_dma_sg_finish(void *buf_priv)

@@ -215,7 +213,7 @@ static void vb2_dma_sg_finish(void *buf_priv)
  	if (buf->db_attach)
  		return;
  
-	dma_sync_sg_for_cpu(buf->dev, sgt->sgl, sgt->orig_nents, buf->dma_dir);
+	dma_sync_sgtable_for_cpu(buf->dev, sgt, buf->dma_dir);
  }
  
  static void *vb2_dma_sg_get_userptr(struct device *dev, unsigned long vaddr,

@@ -258,9 +256,8 @@ static void *vb2_dma_sg_get_userptr(struct device *dev, unsigned long vaddr,
  	 * No need to sync to the device, this will happen later when the
  	 * prepare() memop is called.
  	 */
-	sgt->nents = dma_map_sg_attrs(buf->dev, sgt->sgl, sgt->orig_nents,
-				      buf->dma_dir, DMA_ATTR_SKIP_CPU_SYNC);
-	if (!sgt->nents)
+	if (dma_map_sgtable(buf->dev, sgt, buf->dma_dir,
+			    DMA_ATTR_SKIP_CPU_SYNC)) {