Commit a0812001 authored by Alexander Duyck's avatar Alexander Duyck Committed by Linus Torvalds

arch/sh: add option to skip DMA sync as a part of mapping

This change allows us to pass DMA_ATTR_SKIP_CPU_SYNC which allows us to
avoid invoking cache line invalidation if the driver will just handle it
via a sync_for_cpu or sync_for_device call.

Link: http://lkml.kernel.org/r/20161110113539.76501.6539.stgit@ahduyck-blue-test.jf.intel.comSigned-off-by: default avatarAlexander Duyck <alexander.h.duyck@intel.com>
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Cc: Rich Felker <dalias@libc.org>
Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
parent 6f774809
...@@ -18,7 +18,9 @@ static dma_addr_t nommu_map_page(struct device *dev, struct page *page, ...@@ -18,7 +18,9 @@ static dma_addr_t nommu_map_page(struct device *dev, struct page *page,
dma_addr_t addr = page_to_phys(page) + offset; dma_addr_t addr = page_to_phys(page) + offset;
WARN_ON(size == 0); WARN_ON(size == 0);
dma_cache_sync(dev, page_address(page) + offset, size, dir);
if (!(attrs & DMA_ATTR_SKIP_CPU_SYNC))
dma_cache_sync(dev, page_address(page) + offset, size, dir);
return addr; return addr;
} }
...@@ -35,7 +37,8 @@ static int nommu_map_sg(struct device *dev, struct scatterlist *sg, ...@@ -35,7 +37,8 @@ static int nommu_map_sg(struct device *dev, struct scatterlist *sg,
for_each_sg(sg, s, nents, i) { for_each_sg(sg, s, nents, i) {
BUG_ON(!sg_page(s)); BUG_ON(!sg_page(s));
dma_cache_sync(dev, sg_virt(s), s->length, dir); if (!(attrs & DMA_ATTR_SKIP_CPU_SYNC))
dma_cache_sync(dev, sg_virt(s), s->length, dir);
s->dma_address = sg_phys(s); s->dma_address = sg_phys(s);
s->dma_length = s->length; s->dma_length = s->length;
......
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