[PATCH 13/14] staging: android: ion: Do not sync CPU cache on map/unmap

[Andrew F. Davis]

Buffers may not be mapped from the CPU so skip cache maintenance here.
Accesses from the CPU to a cached heap should be bracketed with
{begin,end}_cpu_access calls so maintenance should not be needed anyway.

Signed-off-by: Andrew F. Davis <a...@ti.com>
---
 drivers/staging/android/ion/ion.c | 7 ++++---
 1 file changed, 4 insertions(+), 3 deletions(-)

diff --git a/drivers/staging/android/ion/ion.c 
b/drivers/staging/android/ion/ion.c
index 14e48f6eb734..09cb5a8e2b09 100644
--- a/drivers/staging/android/ion/ion.c
+++ b/drivers/staging/android/ion/ion.c
@@ -261,8 +261,8 @@ static struct sg_table *ion_map_dma_buf(struct 
dma_buf_attachment *attachment,
 
        table = a->table;
 
-       if (!dma_map_sg(attachment->dev, table->sgl, table->nents,
-                       direction))
+       if (!dma_map_sg_attrs(attachment->dev, table->sgl, table->nents,
+                             direction, DMA_ATTR_SKIP_CPU_SYNC))
                return ERR_PTR(-ENOMEM);
 
        return table;
@@ -272,7 +272,8 @@ static void ion_unmap_dma_buf(struct dma_buf_attachment 
*attachment,
                              struct sg_table *table,
                              enum dma_data_direction direction)
 {
-       dma_unmap_sg(attachment->dev, table->sgl, table->nents, direction);
+       dma_unmap_sg_attrs(attachment->dev, table->sgl, table->nents,
+                          direction, DMA_ATTR_SKIP_CPU_SYNC);
 }
 
 static int ion_mmap(struct dma_buf *dmabuf, struct vm_area_struct *vma)
-- 
2.19.1