Commit 97942c28 authored Jul 31, 2015 by Robin Murphy Committed by Will Deacon Aug 03, 2015

arm64: dma-mapping: Simplify pgprot handling



Since __get_dma_pgprot() does The Right Thing(TM) in the non-coherent
case, and the non-cacheable alias for DMA buffers is private to the
kernel anyway, we can simplify things slightly and make the code more
readable by just using PAGE_KERNEL as the base pgprot.

Suggested-by: Catalin Marinas <catalin.marinas@arm.com>
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Robin Murphy <robin.murphy@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>

parent b511a659

arch/arm64/mm/dma-mapping.c

+2 −3

Original line number	Diff line number	Diff line
		@@ -144,6 +144,7 @@ static void __dma_alloc(struct device dev, size_t size,
		struct page *page;
		void ptr, coherent_ptr;
		bool coherent = is_device_dma_coherent(dev);
		pgprot_t prot = __get_dma_pgprot(attrs, PAGE_KERNEL, false);

		size = PAGE_ALIGN(size);

		@@ -171,9 +172,7 @@ static void __dma_alloc(struct device dev, size_t size,
		/* create a coherent mapping */
		page = virt_to_page(ptr);
		coherent_ptr = dma_common_contiguous_remap(page, size, VM_USERMAP,
		__get_dma_pgprot(attrs,
		__pgprot(PROT_NORMAL_NC), false),
		NULL);
		prot, NULL);
		if (!coherent_ptr)
		goto no_map;

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