[swiotlb PATCH] swiotlb: Minor fix-ups for DMA_ATTR_SKIP_CPU_SYNC support

From: Alexander Duyck
Date: Thu Nov 10 2016 - 13:06:58 EST


I am updating the paths so that instead of trying to pass
"attr | DMA_ATTR_SKIP_CPU_SYNC" we instead just OR the value into attr and
then pass it since attr will not be used after we make the unmap call.

I realized there was one spot I had missed when I was applying the DMA
attribute to the DMA mapping exception handling. This change corrects that.

Finally it looks like there is a stray blank line at the end of the
swiotlb_unmap_sg_attrs function that can be dropped.

Signed-off-by: Alexander Duyck <alexander.h.duyck@xxxxxxxxx>
---
drivers/xen/swiotlb-xen.c | 4 ++--
lib/swiotlb.c | 6 +++---
2 files changed, 5 insertions(+), 5 deletions(-)

diff --git a/drivers/xen/swiotlb-xen.c b/drivers/xen/swiotlb-xen.c
index 3d048af..478fb91 100644
--- a/drivers/xen/swiotlb-xen.c
+++ b/drivers/xen/swiotlb-xen.c
@@ -420,8 +420,8 @@ dma_addr_t xen_swiotlb_map_page(struct device *dev, struct page *page,
if (dma_capable(dev, dev_addr, size))
return dev_addr;

- swiotlb_tbl_unmap_single(dev, map, size, dir,
- attrs | DMA_ATTR_SKIP_CPU_SYNC);
+ attrs |= DMA_ATTR_SKIP_CPU_SYNC;
+ swiotlb_tbl_unmap_single(dev, map, size, dir, attrs);

return DMA_ERROR_CODE;
}
diff --git a/lib/swiotlb.c b/lib/swiotlb.c
index 8e883c7..cb1b54e 100644
--- a/lib/swiotlb.c
+++ b/lib/swiotlb.c
@@ -781,8 +781,8 @@ dma_addr_t swiotlb_map_page(struct device *dev, struct page *page,
if (dma_capable(dev, dev_addr, size))
return dev_addr;

- swiotlb_tbl_unmap_single(dev, map, size, dir,
- attrs | DMA_ATTR_SKIP_CPU_SYNC);
+ attrs |= DMA_ATTR_SKIP_CPU_SYNC;
+ swiotlb_tbl_unmap_single(dev, map, size, dir, attrs);

return phys_to_dma(dev, io_tlb_overflow_buffer);
}
@@ -912,6 +912,7 @@ swiotlb_map_sg_attrs(struct device *hwdev, struct scatterlist *sgl, int nelems,
/* Don't panic here, we expect map_sg users
to do proper error handling. */
swiotlb_full(hwdev, sg->length, dir, 0);
+ attrs |= DMA_ATTR_SKIP_CPU_SYNC;
swiotlb_unmap_sg_attrs(hwdev, sgl, i, dir,
attrs);
sg_dma_len(sgl) = 0;
@@ -943,7 +944,6 @@ swiotlb_unmap_sg_attrs(struct device *hwdev, struct scatterlist *sgl,
for_each_sg(sgl, sg, nelems, i)
unmap_single(hwdev, sg->dma_address, sg_dma_len(sg), dir,
attrs);
-
}
EXPORT_SYMBOL(swiotlb_unmap_sg_attrs);