1 /* SPDX-License-Identifier: GPL-2.0 */ 2 /* 3 * Copyright (C) 2018 Christoph Hellwig. 4 * 5 * DMA operations that map physical memory directly without using an IOMMU. 6 */ 7 #ifndef _KERNEL_DMA_DIRECT_H 8 #define _KERNEL_DMA_DIRECT_H 9 10 #include <linux/dma-direct.h> 11 12 int dma_direct_get_sgtable(struct device *dev, struct sg_table *sgt, 13 void *cpu_addr, dma_addr_t dma_addr, size_t size, 14 unsigned long attrs); 15 bool dma_direct_can_mmap(struct device *dev); 16 int dma_direct_mmap(struct device *dev, struct vm_area_struct *vma, 17 void *cpu_addr, dma_addr_t dma_addr, size_t size, 18 unsigned long attrs); 19 bool dma_direct_need_sync(struct device *dev, dma_addr_t dma_addr); 20 int dma_direct_map_sg(struct device *dev, struct scatterlist *sgl, int nents, 21 enum dma_data_direction dir, unsigned long attrs); 22 size_t dma_direct_max_mapping_size(struct device *dev); 23 24 #if defined(CONFIG_ARCH_HAS_SYNC_DMA_FOR_DEVICE) || \ 25 defined(CONFIG_SWIOTLB) 26 void dma_direct_sync_sg_for_device(struct device *dev, struct scatterlist *sgl, 27 int nents, enum dma_data_direction dir); 28 #else 29 static inline void dma_direct_sync_sg_for_device(struct device *dev, 30 struct scatterlist *sgl, int nents, enum dma_data_direction dir) 31 { 32 } 33 #endif 34 35 #if defined(CONFIG_ARCH_HAS_SYNC_DMA_FOR_CPU) || \ 36 defined(CONFIG_ARCH_HAS_SYNC_DMA_FOR_CPU_ALL) || \ 37 defined(CONFIG_SWIOTLB) 38 void dma_direct_unmap_sg(struct device *dev, struct scatterlist *sgl, 39 int nents, enum dma_data_direction dir, unsigned long attrs); 40 void dma_direct_sync_sg_for_cpu(struct device *dev, 41 struct scatterlist *sgl, int nents, enum dma_data_direction dir); 42 #else 43 static inline void dma_direct_unmap_sg(struct device *dev, 44 struct scatterlist *sgl, int nents, enum dma_data_direction dir, 45 unsigned long attrs) 46 { 47 } 48 static inline void dma_direct_sync_sg_for_cpu(struct device *dev, 49 struct scatterlist *sgl, int nents, enum dma_data_direction dir) 50 { 51 } 52 #endif 53 54 static inline void dma_direct_sync_single_for_device(struct device *dev, 55 dma_addr_t addr, size_t size, enum dma_data_direction dir) 56 { 57 phys_addr_t paddr = dma_to_phys(dev, addr); 58 59 if (unlikely(is_swiotlb_buffer(dev, paddr))) 60 swiotlb_sync_single_for_device(dev, paddr, size, dir); 61 62 if (!dev_is_dma_coherent(dev)) 63 arch_sync_dma_for_device(paddr, size, dir); 64 } 65 66 static inline void dma_direct_sync_single_for_cpu(struct device *dev, 67 dma_addr_t addr, size_t size, enum dma_data_direction dir) 68 { 69 phys_addr_t paddr = dma_to_phys(dev, addr); 70 71 if (!dev_is_dma_coherent(dev)) { 72 arch_sync_dma_for_cpu(paddr, size, dir); 73 arch_sync_dma_for_cpu_all(); 74 } 75 76 if (unlikely(is_swiotlb_buffer(dev, paddr))) 77 swiotlb_sync_single_for_cpu(dev, paddr, size, dir); 78 79 if (dir == DMA_FROM_DEVICE) 80 arch_dma_mark_clean(paddr, size); 81 } 82 83 static inline dma_addr_t dma_direct_map_page(struct device *dev, 84 struct page *page, unsigned long offset, size_t size, 85 enum dma_data_direction dir, unsigned long attrs) 86 { 87 phys_addr_t phys = page_to_phys(page) + offset; 88 dma_addr_t dma_addr = phys_to_dma(dev, phys); 89 90 if (is_swiotlb_force_bounce(dev)) 91 return swiotlb_map(dev, phys, size, dir, attrs); 92 93 if (unlikely(!dma_capable(dev, dma_addr, size, true))) { 94 if (swiotlb_force != SWIOTLB_NO_FORCE) 95 return swiotlb_map(dev, phys, size, dir, attrs); 96 97 dev_WARN_ONCE(dev, 1, 98 "DMA addr %pad+%zu overflow (mask %llx, bus limit %llx).\n", 99 &dma_addr, size, *dev->dma_mask, dev->bus_dma_limit); 100 return DMA_MAPPING_ERROR; 101 } 102 103 if (!dev_is_dma_coherent(dev) && !(attrs & DMA_ATTR_SKIP_CPU_SYNC)) 104 arch_sync_dma_for_device(phys, size, dir); 105 return dma_addr; 106 } 107 108 static inline void dma_direct_unmap_page(struct device *dev, dma_addr_t addr, 109 size_t size, enum dma_data_direction dir, unsigned long attrs) 110 { 111 phys_addr_t phys = dma_to_phys(dev, addr); 112 113 if (!(attrs & DMA_ATTR_SKIP_CPU_SYNC)) 114 dma_direct_sync_single_for_cpu(dev, addr, size, dir); 115 116 if (unlikely(is_swiotlb_buffer(dev, phys))) 117 swiotlb_tbl_unmap_single(dev, phys, size, dir, 118 attrs | DMA_ATTR_SKIP_CPU_SYNC); 119 } 120 #endif /* _KERNEL_DMA_DIRECT_H */ 121