From fd50924917f98f11554e3bf55b0d062e09bce541 Mon Sep 17 00:00:00 2001 From: Christoph Hellwig Date: Mon, 17 Feb 2020 12:46:37 +0100 Subject: ARM/dma-mapping: remove get_coherent_dma_mask The core DMA code already checks for valid DMA masks earlier on, and doesn't allow NULL struct device pointers. Remove the now not required checks. Signed-off-by: Christoph Hellwig --- arch/arm/mm/dma-mapping.c | 41 ++++------------------------------------- 1 file changed, 4 insertions(+), 37 deletions(-) (limited to 'arch/arm/mm') diff --git a/arch/arm/mm/dma-mapping.c b/arch/arm/mm/dma-mapping.c index 9414d72f664b..72ddc3d0f5eb 100644 --- a/arch/arm/mm/dma-mapping.c +++ b/arch/arm/mm/dma-mapping.c @@ -219,7 +219,7 @@ const struct dma_map_ops arm_coherent_dma_ops = { }; EXPORT_SYMBOL(arm_coherent_dma_ops); -static int __dma_supported(struct device *dev, u64 mask, bool warn) +static int __dma_supported(struct device *dev, u64 mask) { unsigned long max_dma_pfn = min(max_pfn - 1, arm_dma_pfn_limit); @@ -227,41 +227,11 @@ static int __dma_supported(struct device *dev, u64 mask, bool warn) * Translate the device's DMA mask to a PFN limit. This * PFN number includes the page which we can DMA to. */ - if (dma_to_pfn(dev, mask) < max_dma_pfn) { - if (warn) - dev_warn(dev, "Coherent DMA mask %#llx (pfn %#lx-%#lx) covers a smaller range of system memory than the DMA zone pfn 0x0-%#lx\n", - mask, - dma_to_pfn(dev, 0), dma_to_pfn(dev, mask) + 1, - max_dma_pfn + 1); + if (dma_to_pfn(dev, mask) < max_dma_pfn) return 0; - } - return 1; } -static u64 get_coherent_dma_mask(struct device *dev) -{ - u64 mask = (u64)DMA_BIT_MASK(32); - - if (dev) { - mask = dev->coherent_dma_mask; - - /* - * Sanity check the DMA mask - it must be non-zero, and - * must be able to be satisfied by a DMA allocation. - */ - if (mask == 0) { - dev_warn(dev, "coherent DMA mask is unset\n"); - return 0; - } - - if (!__dma_supported(dev, mask, true)) - return 0; - } - - return mask; -} - static void __dma_clear_buffer(struct page *page, size_t size, int coherent_flag) { /* @@ -688,7 +658,7 @@ static void *__dma_alloc(struct device *dev, size_t size, dma_addr_t *handle, gfp_t gfp, pgprot_t prot, bool is_coherent, unsigned long attrs, const void *caller) { - u64 mask = get_coherent_dma_mask(dev); + u64 mask = dev->coherent_dma_mask; struct page *page = NULL; void *addr; bool allowblock, cma; @@ -712,9 +682,6 @@ static void *__dma_alloc(struct device *dev, size_t size, dma_addr_t *handle, } #endif - if (!mask) - return NULL; - buf = kzalloc(sizeof(*buf), gfp & ~(__GFP_DMA | __GFP_DMA32 | __GFP_HIGHMEM)); if (!buf) @@ -1095,7 +1062,7 @@ void arm_dma_sync_sg_for_device(struct device *dev, struct scatterlist *sg, */ int arm_dma_supported(struct device *dev, u64 mask) { - return __dma_supported(dev, mask, false); + return __dma_supported(dev, mask); } static const struct dma_map_ops *arm_get_dma_map_ops(bool coherent) -- cgit v1.2.3-59-g8ed1b From 7607cb733fbb6dfac88c4a85c113e8104c91733e Mon Sep 17 00:00:00 2001 From: Christoph Hellwig Date: Mon, 17 Feb 2020 12:50:23 +0100 Subject: ARM/dma-mapping: take the bus limit into account in __dma_alloc The DMA coherent allocator needs to take bus limits into account for picking the zone that the memory is allocated from. Reported-by: Roger Quadros Signed-off-by: Christoph Hellwig Tested-by: Peter Ujfalusi Tested-by: Roger Quadros --- arch/arm/mm/dma-mapping.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'arch/arm/mm') diff --git a/arch/arm/mm/dma-mapping.c b/arch/arm/mm/dma-mapping.c index 72ddc3d0f5eb..87aba505554a 100644 --- a/arch/arm/mm/dma-mapping.c +++ b/arch/arm/mm/dma-mapping.c @@ -658,7 +658,7 @@ static void *__dma_alloc(struct device *dev, size_t size, dma_addr_t *handle, gfp_t gfp, pgprot_t prot, bool is_coherent, unsigned long attrs, const void *caller) { - u64 mask = dev->coherent_dma_mask; + u64 mask = min_not_zero(dev->coherent_dma_mask, dev->bus_dma_limit); struct page *page = NULL; void *addr; bool allowblock, cma; -- cgit v1.2.3-59-g8ed1b From fd27a526bb381f43dded6db30b3b016468ab0e6c Mon Sep 17 00:00:00 2001 From: Christoph Hellwig Date: Mon, 17 Feb 2020 12:48:59 +0100 Subject: ARM/dma-mapping: merge __dma_supported into arm_dma_supported Merge __dma_supported into its only caller, and move the resulting function so that it doesn't need a forward declaration. Also mark it static as there are no callers outside of dma-mapping.c. Signed-off-by: Christoph Hellwig --- arch/arm/include/asm/dma-iommu.h | 2 -- arch/arm/mm/dma-mapping.c | 41 +++++++++++++++++----------------------- 2 files changed, 17 insertions(+), 26 deletions(-) (limited to 'arch/arm/mm') diff --git a/arch/arm/include/asm/dma-iommu.h b/arch/arm/include/asm/dma-iommu.h index 772f48ef84b7..86405cc81385 100644 --- a/arch/arm/include/asm/dma-iommu.h +++ b/arch/arm/include/asm/dma-iommu.h @@ -33,7 +33,5 @@ int arm_iommu_attach_device(struct device *dev, struct dma_iommu_mapping *mapping); void arm_iommu_detach_device(struct device *dev); -int arm_dma_supported(struct device *dev, u64 mask); - #endif /* __KERNEL__ */ #endif diff --git a/arch/arm/mm/dma-mapping.c b/arch/arm/mm/dma-mapping.c index 87aba505554a..8a8949174b1c 100644 --- a/arch/arm/mm/dma-mapping.c +++ b/arch/arm/mm/dma-mapping.c @@ -179,6 +179,23 @@ static void arm_dma_sync_single_for_device(struct device *dev, __dma_page_cpu_to_dev(page, offset, size, dir); } +/* + * Return whether the given device DMA address mask can be supported + * properly. For example, if your device can only drive the low 24-bits + * during bus mastering, then you would pass 0x00ffffff as the mask + * to this function. + */ +static int arm_dma_supported(struct device *dev, u64 mask) +{ + unsigned long max_dma_pfn = min(max_pfn - 1, arm_dma_pfn_limit); + + /* + * Translate the device's DMA mask to a PFN limit. This + * PFN number includes the page which we can DMA to. + */ + return dma_to_pfn(dev, mask) >= max_dma_pfn; +} + const struct dma_map_ops arm_dma_ops = { .alloc = arm_dma_alloc, .free = arm_dma_free, @@ -219,19 +236,6 @@ const struct dma_map_ops arm_coherent_dma_ops = { }; EXPORT_SYMBOL(arm_coherent_dma_ops); -static int __dma_supported(struct device *dev, u64 mask) -{ - unsigned long max_dma_pfn = min(max_pfn - 1, arm_dma_pfn_limit); - - /* - * Translate the device's DMA mask to a PFN limit. This - * PFN number includes the page which we can DMA to. - */ - if (dma_to_pfn(dev, mask) < max_dma_pfn) - return 0; - return 1; -} - static void __dma_clear_buffer(struct page *page, size_t size, int coherent_flag) { /* @@ -1054,17 +1058,6 @@ void arm_dma_sync_sg_for_device(struct device *dev, struct scatterlist *sg, dir); } -/* - * Return whether the given device DMA address mask can be supported - * properly. For example, if your device can only drive the low 24-bits - * during bus mastering, then you would pass 0x00ffffff as the mask - * to this function. - */ -int arm_dma_supported(struct device *dev, u64 mask) -{ - return __dma_supported(dev, mask); -} - static const struct dma_map_ops *arm_get_dma_map_ops(bool coherent) { /* -- cgit v1.2.3-59-g8ed1b