Messages in this thread Patch in this message | | | From | Christoph Hellwig <> | Subject | [PATCH 2/2] dma-mapping: deprecate dma_zalloc_coherent | Date | Fri, 14 Dec 2018 09:25:15 +0100 |
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We now always return zeroed memory from dma_alloc_coherent. Note that simply passing GFP_ZERO to dma_alloc_coherent wasn't always doing the right thing to start with given that various allocators are not backed by the page allocator and thus would ignore GFP_ZERO.
Signed-off-by: Christoph Hellwig <hch@lst.de> --- Documentation/DMA-API.txt | 9 --------- include/linux/dma-mapping.h | 7 ++++--- 2 files changed, 4 insertions(+), 12 deletions(-)
diff --git a/Documentation/DMA-API.txt b/Documentation/DMA-API.txt index 016eb6909b8a..e133ccd60228 100644 --- a/Documentation/DMA-API.txt +++ b/Documentation/DMA-API.txt @@ -58,15 +58,6 @@ specify the ``GFP_`` flags (see kmalloc()) for the allocation (the implementation may choose to ignore flags that affect the location of the returned memory, like GFP_DMA). -:: - - void * - dma_zalloc_coherent(struct device *dev, size_t size, - dma_addr_t *dma_handle, gfp_t flag) - -Wraps dma_alloc_coherent() and also zeroes the returned memory if the -allocation attempt succeeded. - :: void diff --git a/include/linux/dma-mapping.h b/include/linux/dma-mapping.h index f422aec0f53c..a52c6409bdc2 100644 --- a/include/linux/dma-mapping.h +++ b/include/linux/dma-mapping.h @@ -644,12 +644,13 @@ static inline unsigned long dma_max_pfn(struct device *dev) } #endif +/* + * Please always use dma_alloc_coherent instead as it already zeroes the memory! + */ static inline void *dma_zalloc_coherent(struct device *dev, size_t size, dma_addr_t *dma_handle, gfp_t flag) { - void *ret = dma_alloc_coherent(dev, size, dma_handle, - flag | __GFP_ZERO); - return ret; + return dma_alloc_coherent(dev, size, dma_handle, flag); } static inline int dma_get_cache_alignment(void) -- 2.19.2
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