diff options
author | Alexander Duyck <alexander.h.duyck@intel.com> | 2016-12-14 15:05:15 -0800 |
---|---|---|
committer | Linus Torvalds <torvalds@linux-foundation.org> | 2016-12-14 16:04:07 -0800 |
commit | 68bbc28f616c18b695a13e59adefb9a1fc0c46a0 (patch) | |
tree | 60d6d2e062f44c5ad9e3c5e418eda9978370f518 /arch/sparc/kernel/iommu.c | |
parent | a08120017d7d659719d446fb036d500fa9b1e6f9 (diff) |
arch/sparc: add option to skip DMA sync as a part of map and unmap
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/20161110113544.76501.40008.stgit@ahduyck-blue-test.jf.intel.com
Signed-off-by: Alexander Duyck <alexander.h.duyck@intel.com>
Cc: "David S. Miller" <davem@davemloft.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'arch/sparc/kernel/iommu.c')
-rw-r--r-- | arch/sparc/kernel/iommu.c | 4 |
1 files changed, 2 insertions, 2 deletions
diff --git a/arch/sparc/kernel/iommu.c b/arch/sparc/kernel/iommu.c index 852a3291db96..9df997995f6b 100644 --- a/arch/sparc/kernel/iommu.c +++ b/arch/sparc/kernel/iommu.c @@ -415,7 +415,7 @@ static void dma_4u_unmap_page(struct device *dev, dma_addr_t bus_addr, ctx = (iopte_val(*base) & IOPTE_CONTEXT) >> 47UL; /* Step 1: Kick data out of streaming buffers if necessary. */ - if (strbuf->strbuf_enabled) + if (strbuf->strbuf_enabled && !(attrs & DMA_ATTR_SKIP_CPU_SYNC)) strbuf_flush(strbuf, iommu, bus_addr, ctx, npages, direction); @@ -640,7 +640,7 @@ static void dma_4u_unmap_sg(struct device *dev, struct scatterlist *sglist, base = iommu->page_table + entry; dma_handle &= IO_PAGE_MASK; - if (strbuf->strbuf_enabled) + if (strbuf->strbuf_enabled && !(attrs & DMA_ATTR_SKIP_CPU_SYNC)) strbuf_flush(strbuf, iommu, dma_handle, ctx, npages, direction); |