From 7132813c384515c9dede1ae20e56f3895feb7f1e Mon Sep 17 00:00:00 2001 From: "Suzuki K. Poulose" Date: Thu, 19 Mar 2015 18:17:09 +0000 Subject: [PATCH] arm64: Honor __GFP_ZERO in dma allocations Current implementation doesn't zero out the pages allocated. Honor the __GFP_ZERO flag and zero out if set. Cc: # v3.14+ Acked-by: Will Deacon Signed-off-by: Suzuki K. Poulose Signed-off-by: Catalin Marinas --- arch/arm64/mm/dma-mapping.c | 12 +++++++++--- 1 file changed, 9 insertions(+), 3 deletions(-) diff --git a/arch/arm64/mm/dma-mapping.c b/arch/arm64/mm/dma-mapping.c index 58e0c2bdde04..ef7d112f5ce0 100644 --- a/arch/arm64/mm/dma-mapping.c +++ b/arch/arm64/mm/dma-mapping.c @@ -51,7 +51,7 @@ static int __init early_coherent_pool(char *p) } early_param("coherent_pool", early_coherent_pool); -static void *__alloc_from_pool(size_t size, struct page **ret_page) +static void *__alloc_from_pool(size_t size, struct page **ret_page, gfp_t flags) { unsigned long val; void *ptr = NULL; @@ -67,6 +67,8 @@ static void *__alloc_from_pool(size_t size, struct page **ret_page) *ret_page = phys_to_page(phys); ptr = (void *)val; + if (flags & __GFP_ZERO) + memset(ptr, 0, size); } return ptr; @@ -101,6 +103,7 @@ static void *__dma_alloc_coherent(struct device *dev, size_t size, flags |= GFP_DMA; if (IS_ENABLED(CONFIG_DMA_CMA) && (flags & __GFP_WAIT)) { struct page *page; + void *addr; size = PAGE_ALIGN(size); page = dma_alloc_from_contiguous(dev, size >> PAGE_SHIFT, @@ -109,7 +112,10 @@ static void *__dma_alloc_coherent(struct device *dev, size_t size, return NULL; *dma_handle = phys_to_dma(dev, page_to_phys(page)); - return page_address(page); + addr = page_address(page); + if (flags & __GFP_ZERO) + memset(addr, 0, size); + return addr; } else { return swiotlb_alloc_coherent(dev, size, dma_handle, flags); } @@ -146,7 +152,7 @@ static void *__dma_alloc(struct device *dev, size_t size, if (!coherent && !(flags & __GFP_WAIT)) { struct page *page = NULL; - void *addr = __alloc_from_pool(size, &page); + void *addr = __alloc_from_pool(size, &page, flags); if (addr) *dma_handle = phys_to_dma(dev, page_to_phys(page)); -- 2.30.2