From 21caf3a765b0a88f8fedf63b36e5d15683b73fe5 Mon Sep 17 00:00:00 2001 From: Lorenzo Nava Date: Thu, 2 Jul 2015 17:28:03 +0100 Subject: [PATCH] ARM: 8398/1: arm DMA: Fix allocation from CMA for coherent DMA This patch allows the use of CMA for DMA coherent memory allocation. At the moment if the input parameter "is_coherent" is set to true the allocation is not made using the CMA, which I think is not the desired behaviour. The patch covers the allocation and free of memory for coherent DMA. Signed-off-by: Lorenzo Nava Reviewed-by: Catalin Marinas Signed-off-by: Russell King --- arch/arm/mm/dma-mapping.c | 21 ++++++++++++--------- 1 file changed, 12 insertions(+), 9 deletions(-) diff --git a/arch/arm/mm/dma-mapping.c b/arch/arm/mm/dma-mapping.c index 5edf17cf043d..ad7419e69967 100644 --- a/arch/arm/mm/dma-mapping.c +++ b/arch/arm/mm/dma-mapping.c @@ -649,14 +649,18 @@ static void *__dma_alloc(struct device *dev, size_t size, dma_addr_t *handle, size = PAGE_ALIGN(size); want_vaddr = !dma_get_attr(DMA_ATTR_NO_KERNEL_MAPPING, attrs); - if (is_coherent || nommu()) + if (nommu()) + addr = __alloc_simple_buffer(dev, size, gfp, &page); + else if (dev_get_cma_area(dev) && (gfp & __GFP_WAIT)) + addr = __alloc_from_contiguous(dev, size, prot, &page, + caller, want_vaddr); + else if (is_coherent) addr = __alloc_simple_buffer(dev, size, gfp, &page); else if (!(gfp & __GFP_WAIT)) addr = __alloc_from_pool(size, &page); - else if (!dev_get_cma_area(dev)) - addr = __alloc_remap_buffer(dev, size, gfp, prot, &page, caller, want_vaddr); else - addr = __alloc_from_contiguous(dev, size, prot, &page, caller, want_vaddr); + addr = __alloc_remap_buffer(dev, size, gfp, prot, &page, + caller, want_vaddr); if (page) *handle = pfn_to_dma(dev, page_to_pfn(page)); @@ -684,13 +688,12 @@ void *arm_dma_alloc(struct device *dev, size_t size, dma_addr_t *handle, static void *arm_coherent_dma_alloc(struct device *dev, size_t size, dma_addr_t *handle, gfp_t gfp, struct dma_attrs *attrs) { - pgprot_t prot = __get_dma_pgprot(attrs, PAGE_KERNEL); void *memory; if (dma_alloc_from_coherent(dev, size, handle, &memory)) return memory; - return __dma_alloc(dev, size, handle, gfp, prot, true, + return __dma_alloc(dev, size, handle, gfp, PAGE_KERNEL, true, attrs, __builtin_return_address(0)); } @@ -754,12 +757,12 @@ static void __arm_dma_free(struct device *dev, size_t size, void *cpu_addr, size = PAGE_ALIGN(size); - if (is_coherent || nommu()) { + if (nommu()) { __dma_free_buffer(page, size); - } else if (__free_from_pool(cpu_addr, size)) { + } else if (!is_coherent && __free_from_pool(cpu_addr, size)) { return; } else if (!dev_get_cma_area(dev)) { - if (want_vaddr) + if (want_vaddr && !is_coherent) __dma_free_remap(cpu_addr, size); __dma_free_buffer(page, size); } else { -- 2.39.5