From: Alexander Duyck <alexander.h.duyck@xxxxxxxxx> Subject: 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@xxxxxxxxxxxxxxxxxxxxxxxxxxxxxx Signed-off-by: Alexander Duyck <alexander.h.duyck@xxxxxxxxx> Cc: Russell King <linux@xxxxxxxxxxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- arch/arm/common/dmabounce.c | 16 ++++++++++------ 1 file changed, 10 insertions(+), 6 deletions(-) diff -puN arch/arm/common/dmabounce.c~arch-arm-add-option-to-skip-sync-on-dma-map-and-unmap arch/arm/common/dmabounce.c --- a/arch/arm/common/dmabounce.c~arch-arm-add-option-to-skip-sync-on-dma-map-and-unmap +++ a/arch/arm/common/dmabounce.c @@ -243,7 +243,8 @@ static int needs_bounce(struct device *d } 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(stru __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(stru } 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 d 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(str 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 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, _ -- To unsubscribe from this list: send the line "unsubscribe mm-commits" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
