diff options
| author | Alexander Duyck <alexander.h.duyck@intel.com> | 2016-12-14 15:04:32 -0800 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2016-12-14 16:04:07 -0800 |
| commit | fc1b138de7917d8fda5995aeecdb10c8182d9f75 (patch) | |
| tree | fffdb4f1cb6d19f1aea545e92aa4f0ceea9ad441 /arch | |
| parent | 8a3385d2d47cd912f28d23bd2225ee37de518d86 (diff) | |
| download | linux-fc1b138de7917d8fda5995aeecdb10c8182d9f75.tar.gz linux-fc1b138de7917d8fda5995aeecdb10c8182d9f75.tar.xz | |
arch/arm: add option to skip sync on DMA map and unmap
The use of DMA_ATTR_SKIP_CPU_SYNC was not consistent across all of the
DMA APIs in the arch/arm folder. This change is meant to correct that
so that we get consistent behavior.
Link: http://lkml.kernel.org/r/20161110113424.76501.2715.stgit@ahduyck-blue-test.jf.intel.com
Signed-off-by: Alexander Duyck <alexander.h.duyck@intel.com>
Cc: Russell King <linux@armlinux.org.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'arch')
| -rw-r--r-- | arch/arm/common/dmabounce.c | 16 |
1 files changed, 10 insertions, 6 deletions
diff --git a/arch/arm/common/dmabounce.c b/arch/arm/common/dmabounce.c index 301281645d08..75055df1cda3 100644 --- a/arch/arm/common/dmabounce.c +++ b/arch/arm/common/dmabounce.c @@ -243,7 +243,8 @@ static int needs_bounce(struct device *dev, dma_addr_t dma_addr, size_t size) } static inline dma_addr_t map_single(struct device *dev, void *ptr, size_t size, - enum dma_data_direction dir) + enum dma_data_direction dir, + unsigned long attrs) { struct dmabounce_device_info *device_info = dev->archdata.dmabounce; struct safe_buffer *buf; @@ -262,7 +263,8 @@ static inline dma_addr_t map_single(struct device *dev, void *ptr, size_t size, __func__, buf->ptr, virt_to_dma(dev, buf->ptr), buf->safe, buf->safe_dma_addr); - if (dir == DMA_TO_DEVICE || dir == DMA_BIDIRECTIONAL) { + if ((dir == DMA_TO_DEVICE || dir == DMA_BIDIRECTIONAL) && + !(attrs & DMA_ATTR_SKIP_CPU_SYNC)) { dev_dbg(dev, "%s: copy unsafe %p to safe %p, size %d\n", __func__, ptr, buf->safe, size); memcpy(buf->safe, ptr, size); @@ -272,7 +274,8 @@ static inline dma_addr_t map_single(struct device *dev, void *ptr, size_t size, } static inline void unmap_single(struct device *dev, struct safe_buffer *buf, - size_t size, enum dma_data_direction dir) + size_t size, enum dma_data_direction dir, + unsigned long attrs) { BUG_ON(buf->size != size); BUG_ON(buf->direction != dir); @@ -283,7 +286,8 @@ static inline void unmap_single(struct device *dev, struct safe_buffer *buf, DO_STATS(dev->archdata.dmabounce->bounce_count++); - if (dir == DMA_FROM_DEVICE || dir == DMA_BIDIRECTIONAL) { + if ((dir == DMA_FROM_DEVICE || dir == DMA_BIDIRECTIONAL) && + !(attrs & DMA_ATTR_SKIP_CPU_SYNC)) { void *ptr = buf->ptr; dev_dbg(dev, "%s: copy back safe %p to unsafe %p size %d\n", @@ -334,7 +338,7 @@ static dma_addr_t dmabounce_map_page(struct device *dev, struct page *page, return DMA_ERROR_CODE; } - return map_single(dev, page_address(page) + offset, size, dir); + return map_single(dev, page_address(page) + offset, size, dir, attrs); } /* @@ -357,7 +361,7 @@ static void dmabounce_unmap_page(struct device *dev, dma_addr_t dma_addr, size_t return; } - unmap_single(dev, buf, size, dir); + unmap_single(dev, buf, size, dir, attrs); } static int __dmabounce_sync_for_cpu(struct device *dev, dma_addr_t addr, |