From: Marek Szyprowski <m.szyprowski@xxxxxxxxxxx> Subject: kernel/dma: remove unsupported gfp_mask parameter from dma_alloc_from_contiguous() The CMA memory allocator doesn't support standard gfp flags for memory allocation, so there is no point having it as a parameter for dma_alloc_from_contiguous() function. Replace it by a boolean no_warn argument, which covers all the underlaying cma_alloc() function supports. This will help to avoid giving false feeling that this function supports standard gfp flags and callers can pass __GFP_ZERO to get zeroed buffer, what has already been an issue: see commit dd65a941f6ba ("arm64: dma-mapping: clear buffers allocated with FORCE_CONTIGUOUS flag"). Link: http://lkml.kernel.org/r/20180709122020eucas1p21a71b092975cb4a3b9954ffc63f699d1~-sqUFoa-h2939329393eucas1p2Y@xxxxxxxxxxxxxxxxxxxx Signed-off-by: Marek Szyprowski <m.szyprowski@xxxxxxxxxxx> Acked-by: Michał Nazarewicz <mina86@xxxxxxxxxx> Acked-by: Vlastimil Babka <vbabka@xxxxxxx> Reviewed-by: Christoph Hellwig <hch@xxxxxx> Cc: Laura Abbott <labbott@xxxxxxxxxx> Cc: Michal Hocko <mhocko@xxxxxxxx> Cc: Joonsoo Kim <js1304@xxxxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- arch/arm/mm/dma-mapping.c | 5 +++-- arch/arm64/mm/dma-mapping.c | 4 ++-- arch/xtensa/kernel/pci-dma.c | 2 +- drivers/iommu/amd_iommu.c | 2 +- drivers/iommu/intel-iommu.c | 3 ++- include/linux/dma-contiguous.h | 4 ++-- kernel/dma/contiguous.c | 7 +++---- kernel/dma/direct.c | 3 ++- 8 files changed, 16 insertions(+), 14 deletions(-) --- a/arch/arm64/mm/dma-mapping.c~dma-remove-unsupported-gfp_mask-parameter-from-dma_alloc_from_contiguous +++ a/arch/arm64/mm/dma-mapping.c @@ -355,7 +355,7 @@ static int __init atomic_pool_init(void) if (dev_get_cma_area(NULL)) page = dma_alloc_from_contiguous(NULL, nr_pages, - pool_size_order, GFP_KERNEL); + pool_size_order, false); else page = alloc_pages(GFP_DMA32, pool_size_order); @@ -573,7 +573,7 @@ static void *__iommu_alloc_attrs(struct struct page *page; page = dma_alloc_from_contiguous(dev, size >> PAGE_SHIFT, - get_order(size), gfp); + get_order(size), gfp & __GFP_NOWARN); if (!page) return NULL; --- a/arch/arm/mm/dma-mapping.c~dma-remove-unsupported-gfp_mask-parameter-from-dma_alloc_from_contiguous +++ a/arch/arm/mm/dma-mapping.c @@ -594,7 +594,7 @@ static void *__alloc_from_contiguous(str struct page *page; void *ptr = NULL; - page = dma_alloc_from_contiguous(dev, count, order, gfp); + page = dma_alloc_from_contiguous(dev, count, order, gfp & __GFP_NOWARN); if (!page) return NULL; @@ -1299,7 +1299,8 @@ static struct page **__iommu_alloc_buffe unsigned long order = get_order(size); struct page *page; - page = dma_alloc_from_contiguous(dev, count, order, gfp); + page = dma_alloc_from_contiguous(dev, count, order, + gfp & __GFP_NOWARN); if (!page) goto error; --- a/arch/xtensa/kernel/pci-dma.c~dma-remove-unsupported-gfp_mask-parameter-from-dma_alloc_from_contiguous +++ a/arch/xtensa/kernel/pci-dma.c @@ -137,7 +137,7 @@ static void *xtensa_dma_alloc(struct dev if (gfpflags_allow_blocking(flag)) page = dma_alloc_from_contiguous(dev, count, get_order(size), - flag); + flag & __GFP_NOWARN); if (!page) page = alloc_pages(flag, get_order(size)); --- a/drivers/iommu/amd_iommu.c~dma-remove-unsupported-gfp_mask-parameter-from-dma_alloc_from_contiguous +++ a/drivers/iommu/amd_iommu.c @@ -2620,7 +2620,7 @@ static void *alloc_coherent(struct devic return NULL; page = dma_alloc_from_contiguous(dev, size >> PAGE_SHIFT, - get_order(size), flag); + get_order(size), flag & __GFP_NOWARN); if (!page) return NULL; } --- a/drivers/iommu/intel-iommu.c~dma-remove-unsupported-gfp_mask-parameter-from-dma_alloc_from_contiguous +++ a/drivers/iommu/intel-iommu.c @@ -3758,7 +3758,8 @@ static void *intel_alloc_coherent(struct if (gfpflags_allow_blocking(flags)) { unsigned int count = size >> PAGE_SHIFT; - page = dma_alloc_from_contiguous(dev, count, order, flags); + page = dma_alloc_from_contiguous(dev, count, order, + flags & __GFP_NOWARN); if (page && iommu_no_mapping(dev) && page_to_phys(page) + size > dev->coherent_dma_mask) { dma_release_from_contiguous(dev, page, count); --- a/include/linux/dma-contiguous.h~dma-remove-unsupported-gfp_mask-parameter-from-dma_alloc_from_contiguous +++ a/include/linux/dma-contiguous.h @@ -112,7 +112,7 @@ static inline int dma_declare_contiguous } struct page *dma_alloc_from_contiguous(struct device *dev, size_t count, - unsigned int order, gfp_t gfp_mask); + unsigned int order, bool no_warn); bool dma_release_from_contiguous(struct device *dev, struct page *pages, int count); @@ -145,7 +145,7 @@ int dma_declare_contiguous(struct device static inline struct page *dma_alloc_from_contiguous(struct device *dev, size_t count, - unsigned int order, gfp_t gfp_mask) + unsigned int order, bool no_warn) { return NULL; } --- a/kernel/dma/contiguous.c~dma-remove-unsupported-gfp_mask-parameter-from-dma_alloc_from_contiguous +++ a/kernel/dma/contiguous.c @@ -178,7 +178,7 @@ int __init dma_contiguous_reserve_area(p * @dev: Pointer to device for which the allocation is performed. * @count: Requested number of pages. * @align: Requested alignment of pages (in PAGE_SIZE order). - * @gfp_mask: GFP flags to use for this allocation. + * @no_warn: Avoid printing message about failed allocation. * * This function allocates memory buffer for specified device. It uses * device specific contiguous memory area if available or the default @@ -186,13 +186,12 @@ int __init dma_contiguous_reserve_area(p * function. */ struct page *dma_alloc_from_contiguous(struct device *dev, size_t count, - unsigned int align, gfp_t gfp_mask) + unsigned int align, bool no_warn) { if (align > CONFIG_CMA_ALIGNMENT) align = CONFIG_CMA_ALIGNMENT; - return cma_alloc(dev_get_cma_area(dev), count, align, - gfp_mask & __GFP_NOWARN); + return cma_alloc(dev_get_cma_area(dev), count, align, no_warn); } /** --- a/kernel/dma/direct.c~dma-remove-unsupported-gfp_mask-parameter-from-dma_alloc_from_contiguous +++ a/kernel/dma/direct.c @@ -78,7 +78,8 @@ void *dma_direct_alloc(struct device *de again: /* CMA can be used only in the context which permits sleeping */ if (gfpflags_allow_blocking(gfp)) { - page = dma_alloc_from_contiguous(dev, count, page_order, gfp); + page = dma_alloc_from_contiguous(dev, count, page_order, + gfp & __GFP_NOWARN); if (page && !dma_coherent_ok(dev, page_to_phys(page), size)) { dma_release_from_contiguous(dev, page, count); page = NULL; _