x86: make dma_cache_sync a no-op
authorChristoph Hellwig <hch@lst.de>
Sun, 27 Aug 2017 08:06:22 +0000 (10:06 +0200)
committerChristoph Hellwig <hch@lst.de>
Thu, 19 Oct 2017 14:37:13 +0000 (16:37 +0200)
commit95e499fc7fe9c58efedc079634582164de6bbd90
tree72ade57d8ba5d4474c4b7eff5ef18a6063283dda
parentacfef4f126a716018127dcf147be0cc16c304e72
x86: make dma_cache_sync a no-op

x86 does not implement DMA_ATTR_NON_CONSISTENT allocations, so it doesn't
make any sense to do any work in dma_cache_sync given that it must be a
no-op when dma_alloc_attrs returns coherent memory.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Robin Murphy <robin.murphy@arm.com>
arch/x86/include/asm/dma-mapping.h