[PATCH 18/31] nios2: handle page-less SG entries

Christoph Hellwig
2015-08-12T07:05:37Z

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/nios2/mm/dma-mapping.c | 29 +++++++++++++++--------------
1 file changed, 15 insertions(+), 14 deletions(-)

diff --git a/arch/nios2/mm/dma-mapping.c b/arch/nios2/mm/dma-mapping.c
index ac5da75..1a0a68d 100644
--- a/arch/nios2/mm/dma-mapping.c
+++ b/arch/nios2/mm/dma-mapping.c
@@ -64,13 +64,11 @@ int dma_map_sg(struct device *dev, struct scatterlist *sg, int nents,
BUG_ON(!valid_dma_direction(direction));

for_each_sg(sg, sg, nents, i) {
- void *addr;
-
- addr = sg_virt(sg);
- if (addr) {
- __dma_sync_for_device(addr, sg->length, direction);
- sg->dma_address = sg_phys(sg);
+ if (sg_has_page(sg)) {
+ __dma_sync_for_device(sg_virt(sg), sg->length,
+ direction);
}
+ sg->dma_address = sg_phys(sg);
}

return nents;
@@ -113,9 +111,8 @@ void dma_unmap_sg(struct device *dev, struct scatterlist *sg, int nhwentries,
return;

for_each_sg(sg, sg, nhwentries, i) {
- addr = sg_virt(sg);
- if (addr)
- __dma_sync_for_cpu(addr, sg->length, direction);
+ if (sg_has_page(sg))
+ __dma_sync_for_cpu(sg_virt(sg), sg->length, direction);
}
}
EXPORT_SYMBOL(dma_unmap_sg);
@@ -166,8 +163,10 @@ void dma_sync_sg_for_cpu(struct device *dev, struct scatterlist *sg, int nelems,
BUG_ON(!valid_dma_direction(direction));

/* Make sure that gcc doesn't leave the empty loop body. */
- for_each_sg(sg, sg, nelems, i)
- __dma_sync_for_cpu(sg_virt(sg), sg->length, direction);
+ for_each_sg(sg, sg, nelems, i) {
+ if (sg_has_page(sg))
+ __dma_sync_for_cpu(sg_virt(sg), sg->length, direction);
+ }
}
EXPORT_SYMBOL(dma_sync_sg_for_cpu);

@@ -179,8 +178,10 @@ void dma_sync_sg_for_device(struct device *dev, struct scatterlist *sg,
BUG_ON(!valid_dma_direction(direction));

/* Make sure that gcc doesn't leave the empty loop body. */
- for_each_sg(sg, sg, nelems, i)
- __dma_sync_for_device(sg_virt(sg), sg->length, direction);
-
+ for_each_sg(sg, sg, nelems, i) {
+ if (sg_has_page(sg))
+ __dma_sync_for_device(sg_virt(sg), sg->length,
+ direction);
+ }
}
EXPORT_SYMBOL(dma_sync_sg_for_device);
--
1.9.1