From 7d2822dfea122acd498a8ec4481af5d51777fec1 Mon Sep 17 00:00:00 2001 From: Sricharan R Date: Fri, 6 Jan 2017 18:58:13 +0530 Subject: arm/dma-mapping: Implement DMA_ATTR_PRIVILEGED The newly added DMA_ATTR_PRIVILEGED is useful for creating mappings that are only accessible to privileged DMA engines. Adding it to the arm dma-mapping.c so that the ARM32 DMA IOMMU mapper can make use of it. Signed-off-by: Sricharan R Reviewed-by: Will Deacon Signed-off-by: Will Deacon --- arch/arm/mm/dma-mapping.c | 60 +++++++++++++++++++++++------------------------ 1 file changed, 30 insertions(+), 30 deletions(-) (limited to 'arch/arm/mm') diff --git a/arch/arm/mm/dma-mapping.c b/arch/arm/mm/dma-mapping.c index ab7710002ba6..82d3e79ec82b 100644 --- a/arch/arm/mm/dma-mapping.c +++ b/arch/arm/mm/dma-mapping.c @@ -1171,6 +1171,25 @@ core_initcall(dma_debug_do_init); #ifdef CONFIG_ARM_DMA_USE_IOMMU +static int __dma_info_to_prot(enum dma_data_direction dir, unsigned long attrs) +{ + int prot = 0; + + if (attrs & DMA_ATTR_PRIVILEGED) + prot |= IOMMU_PRIV; + + switch (dir) { + case DMA_BIDIRECTIONAL: + return prot | IOMMU_READ | IOMMU_WRITE; + case DMA_TO_DEVICE: + return prot | IOMMU_READ; + case DMA_FROM_DEVICE: + return prot | IOMMU_WRITE; + default: + return prot; + } +} + /* IOMMU */ static int extend_iommu_mapping(struct dma_iommu_mapping *mapping); @@ -1394,7 +1413,8 @@ __iommu_alloc_remap(struct page **pages, size_t size, gfp_t gfp, pgprot_t prot, * Create a mapping in device IO address space for specified pages */ static dma_addr_t -__iommu_create_mapping(struct device *dev, struct page **pages, size_t size) +__iommu_create_mapping(struct device *dev, struct page **pages, size_t size, + unsigned long attrs) { struct dma_iommu_mapping *mapping = to_dma_iommu_mapping(dev); unsigned int count = PAGE_ALIGN(size) >> PAGE_SHIFT; @@ -1419,7 +1439,7 @@ __iommu_create_mapping(struct device *dev, struct page **pages, size_t size) len = (j - i) << PAGE_SHIFT; ret = iommu_map(mapping->domain, iova, phys, len, - IOMMU_READ|IOMMU_WRITE); + __dma_info_to_prot(DMA_BIDIRECTIONAL, attrs)); if (ret < 0) goto fail; iova += len; @@ -1476,7 +1496,8 @@ static struct page **__iommu_get_pages(void *cpu_addr, unsigned long attrs) } static void *__iommu_alloc_simple(struct device *dev, size_t size, gfp_t gfp, - dma_addr_t *handle, int coherent_flag) + dma_addr_t *handle, int coherent_flag, + unsigned long attrs) { struct page *page; void *addr; @@ -1488,7 +1509,7 @@ static void *__iommu_alloc_simple(struct device *dev, size_t size, gfp_t gfp, if (!addr) return NULL; - *handle = __iommu_create_mapping(dev, &page, size); + *handle = __iommu_create_mapping(dev, &page, size, attrs); if (*handle == DMA_ERROR_CODE) goto err_mapping; @@ -1522,7 +1543,7 @@ static void *__arm_iommu_alloc_attrs(struct device *dev, size_t size, if (coherent_flag == COHERENT || !gfpflags_allow_blocking(gfp)) return __iommu_alloc_simple(dev, size, gfp, handle, - coherent_flag); + coherent_flag, attrs); /* * Following is a work-around (a.k.a. hack) to prevent pages @@ -1537,7 +1558,7 @@ static void *__arm_iommu_alloc_attrs(struct device *dev, size_t size, if (!pages) return NULL; - *handle = __iommu_create_mapping(dev, pages, size); + *handle = __iommu_create_mapping(dev, pages, size, attrs); if (*handle == DMA_ERROR_CODE) goto err_buffer; @@ -1672,27 +1693,6 @@ static int arm_iommu_get_sgtable(struct device *dev, struct sg_table *sgt, GFP_KERNEL); } -static int __dma_direction_to_prot(enum dma_data_direction dir) -{ - int prot; - - switch (dir) { - case DMA_BIDIRECTIONAL: - prot = IOMMU_READ | IOMMU_WRITE; - break; - case DMA_TO_DEVICE: - prot = IOMMU_READ; - break; - case DMA_FROM_DEVICE: - prot = IOMMU_WRITE; - break; - default: - prot = 0; - } - - return prot; -} - /* * Map a part of the scatter-gather list into contiguous io address space */ @@ -1722,7 +1722,7 @@ static int __map_sg_chunk(struct device *dev, struct scatterlist *sg, if (!is_coherent && (attrs & DMA_ATTR_SKIP_CPU_SYNC) == 0) __dma_page_cpu_to_dev(sg_page(s), s->offset, s->length, dir); - prot = __dma_direction_to_prot(dir); + prot = __dma_info_to_prot(dir, attrs); ret = iommu_map(mapping->domain, iova, phys, len, prot); if (ret < 0) @@ -1930,7 +1930,7 @@ static dma_addr_t arm_coherent_iommu_map_page(struct device *dev, struct page *p if (dma_addr == DMA_ERROR_CODE) return dma_addr; - prot = __dma_direction_to_prot(dir); + prot = __dma_info_to_prot(dir, attrs); ret = iommu_map(mapping->domain, dma_addr, page_to_phys(page), len, prot); if (ret < 0) @@ -2036,7 +2036,7 @@ static dma_addr_t arm_iommu_map_resource(struct device *dev, if (dma_addr == DMA_ERROR_CODE) return dma_addr; - prot = __dma_direction_to_prot(dir) | IOMMU_MMIO; + prot = __dma_info_to_prot(dir, attrs) | IOMMU_MMIO; ret = iommu_map(mapping->domain, dma_addr, addr, len, prot); if (ret < 0) -- cgit