[PATCH 19/31] arc: handle page-less SG entries

Christoph Hellwig
2015-08-12T07:05:38Z

Make all cache invalidation conditional on sg_has_page() and use
sg_phys to get the physical address directly.

Signed-off-by: Christoph Hellwig <hch@lst.de>
---
arch/arc/include/asm/dma-mapping.h | 26 +++++++++++++++++++-------
1 file changed, 19 insertions(+), 7 deletions(-)

diff --git a/arch/arc/include/asm/dma-mapping.h b/arch/arc/include/asm/dma-mapping.h
index 2d28ba9..42eb526 100644
--- a/arch/arc/include/asm/dma-mapping.h
+++ b/arch/arc/include/asm/dma-mapping.h
@@ -108,9 +108,13 @@ dma_map_sg(struct device *dev, struct scatterlist *sg,
struct scatterlist *s;
int i;

- for_each_sg(sg, s, nents, i)
- s->dma_address = dma_map_page(dev, sg_page(s), s->offset,
- s->length, dir);
+ for_each_sg(sg, s, nents, i) {
+ if (sg_has_page(s)) {
+ _dma_cache_sync((unsigned long)sg_virt(s), s->length,
+ dir);
+ }
+ s->dma_address = sg_phys(s);
+ }

return nents;
}
@@ -163,8 +167,12 @@ dma_sync_sg_for_cpu(struct device *dev, struct scatterlist *sglist, int nelems,
int i;
struct scatterlist *sg;

- for_each_sg(sglist, sg, nelems, i)
- _dma_cache_sync((unsigned int)sg_virt(sg), sg->length, dir);
+ for_each_sg(sglist, sg, nelems, i) {
+ if (sg_has_page(sg)) {
+ _dma_cache_sync((unsigned int)sg_virt(sg), sg->length,
+ dir);
+ }
+ }
}

static inline void
@@ -174,8 +182,12 @@ dma_sync_sg_for_device(struct device *dev, struct scatterlist *sglist,
int i;
struct scatterlist *sg;

- for_each_sg(sglist, sg, nelems, i)
- _dma_cache_sync((unsigned int)sg_virt(sg), sg->length, dir);
+ for_each_sg(sglist, sg, nelems, i) {
+ if (sg_has_page(sg)) {
+ _dma_cache_sync((unsigned int)sg_virt(sg), sg->length,
+ dir);
+ }
+ }
}

static inline int dma_supported(struct device *dev, u64 dma_mask)
--
1.9.1