Merge tag 'dma-mapping-5.18-2' of git://git.infradead.org/users/hch/dma-mapping

torvalds · torvalds · commit b00868396dbd · 2022-04-16T11:20:21.000-07:00
Pull dma-mapping fix from Christoph Hellwig:

 - avoid a double memory copy for swiotlb (Chao Gao)

* tag 'dma-mapping-5.18-2' of git://git.infradead.org/users/hch/dma-mapping:
  dma-direct: avoid redundant memory sync for swiotlb
diff --git a/kernel/dma/direct.h b/kernel/dma/direct.h
@@ -114,6 +114,7 @@ static inline void dma_direct_unmap_page(struct device *dev, dma_addr_t addr,
 		dma_direct_sync_single_for_cpu(dev, addr, size, dir);
 
 	if (unlikely(is_swiotlb_buffer(dev, phys)))
-		swiotlb_tbl_unmap_single(dev, phys, size, dir, attrs);
+		swiotlb_tbl_unmap_single(dev, phys, size, dir,
+					 attrs | DMA_ATTR_SKIP_CPU_SYNC);
 }
 #endif /* _KERNEL_DMA_DIRECT_H */

Original file line number	Diff line number	Diff line change
`@@ -114,6 +114,7 @@ static inline void dma_direct_unmap_page(struct device *dev, dma_addr_t addr,`
`114`	`114`	`dma_direct_sync_single_for_cpu(dev, addr, size, dir);`
`115`	`115`
`116`	`116`	`if (unlikely(is_swiotlb_buffer(dev, phys)))`
`117`		`- swiotlb_tbl_unmap_single(dev, phys, size, dir, attrs);`
	`117`	`+ swiotlb_tbl_unmap_single(dev, phys, size, dir,`
	`118`	`+ attrs \| DMA_ATTR_SKIP_CPU_SYNC);`
`118`	`119`	`}`
`119`	`120`	`#endif /* _KERNEL_DMA_DIRECT_H */`