[PATCH 22/31] metag: handle page-less SG entries

From: Christoph Hellwig
Date: Wed Aug 12 2015 - 03:13:57 EST


Make all cache invalidation conditional on sg_has_page().

Signed-off-by: Christoph Hellwig <hch@xxxxxx>
---
arch/metag/include/asm/dma-mapping.h | 22 ++++++++++++----------
1 file changed, 12 insertions(+), 10 deletions(-)

diff --git a/arch/metag/include/asm/dma-mapping.h b/arch/metag/include/asm/dma-mapping.h
index eb5cdec..2ae9057 100644
--- a/arch/metag/include/asm/dma-mapping.h
+++ b/arch/metag/include/asm/dma-mapping.h
@@ -55,10 +55,9 @@ dma_map_sg(struct device *dev, struct scatterlist *sglist, int nents,
WARN_ON(nents == 0 || sglist[0].length == 0);

for_each_sg(sglist, sg, nents, i) {
- BUG_ON(!sg_page(sg));
-
sg->dma_address = sg_phys(sg);
- dma_sync_for_device(sg_virt(sg), sg->length, direction);
+ if (sg_has_page(sg))
+ dma_sync_for_device(sg_virt(sg), sg->length, direction);
}

return nents;
@@ -94,10 +93,9 @@ dma_unmap_sg(struct device *dev, struct scatterlist *sglist, int nhwentries,
WARN_ON(nhwentries == 0 || sglist[0].length == 0);

for_each_sg(sglist, sg, nhwentries, i) {
- BUG_ON(!sg_page(sg));
-
sg->dma_address = sg_phys(sg);
- dma_sync_for_cpu(sg_virt(sg), sg->length, direction);
+ if (sg_has_page(sg))
+ dma_sync_for_cpu(sg_virt(sg), sg->length, direction);
}
}

@@ -140,8 +138,10 @@ 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_sync_for_cpu(sg_virt(sg), sg->length, direction);
+ for_each_sg(sglist, sg, nelems, i) {
+ if (sg_has_page(sg))
+ dma_sync_for_cpu(sg_virt(sg), sg->length, direction);
+ }
}

static inline void
@@ -151,8 +151,10 @@ dma_sync_sg_for_device(struct device *dev, struct scatterlist *sglist,
int i;
struct scatterlist *sg;

- for_each_sg(sglist, sg, nelems, i)
- dma_sync_for_device(sg_virt(sg), sg->length, direction);
+ for_each_sg(sglist, sg, nelems, i) {
+ if (sg_has_page(sg))
+ dma_sync_for_device(sg_virt(sg), sg->length, direction);
+ }
}

static inline int
--
1.9.1

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