1 #ifndef _ASM_X86_DMA_MAPPING_H 2 #define _ASM_X86_DMA_MAPPING_H 3 4 /* 5 * IOMMU interface. See Documentation/PCI/PCI-DMA-mapping.txt and 6 * Documentation/DMA-API.txt for documentation. 7 */ 8 9 #include <linux/kmemcheck.h> 10 #include <linux/scatterlist.h> 11 #include <linux/dma-debug.h> 12 #include <linux/dma-attrs.h> 13 #include <asm/io.h> 14 #include <asm/swiotlb.h> 15 #include <asm-generic/dma-coherent.h> 16 17 extern dma_addr_t bad_dma_address; 18 extern int iommu_merge; 19 extern struct device x86_dma_fallback_dev; 20 extern int panic_on_overflow; 21 22 extern struct dma_map_ops *dma_ops; 23 24 static inline struct dma_map_ops *get_dma_ops(struct device *dev) 25 { 26 #ifdef CONFIG_X86_32 27 return dma_ops; 28 #else 29 if (unlikely(!dev) || !dev->archdata.dma_ops) 30 return dma_ops; 31 else 32 return dev->archdata.dma_ops; 33 #endif 34 } 35 36 #include <asm-generic/dma-mapping-common.h> 37 38 /* Make sure we keep the same behaviour */ 39 static inline int dma_mapping_error(struct device *dev, dma_addr_t dma_addr) 40 { 41 struct dma_map_ops *ops = get_dma_ops(dev); 42 if (ops->mapping_error) 43 return ops->mapping_error(dev, dma_addr); 44 45 return (dma_addr == bad_dma_address); 46 } 47 48 #define dma_alloc_noncoherent(d, s, h, f) dma_alloc_coherent(d, s, h, f) 49 #define dma_free_noncoherent(d, s, v, h) dma_free_coherent(d, s, v, h) 50 #define dma_is_consistent(d, h) (1) 51 52 extern int dma_supported(struct device *hwdev, u64 mask); 53 extern int dma_set_mask(struct device *dev, u64 mask); 54 55 extern void *dma_generic_alloc_coherent(struct device *dev, size_t size, 56 dma_addr_t *dma_addr, gfp_t flag); 57 58 static inline void 59 dma_cache_sync(struct device *dev, void *vaddr, size_t size, 60 enum dma_data_direction dir) 61 { 62 flush_write_buffers(); 63 } 64 65 static inline int dma_get_cache_alignment(void) 66 { 67 /* no easy way to get cache size on all x86, so return the 68 * maximum possible, to be safe */ 69 return boot_cpu_data.x86_clflush_size; 70 } 71 72 static inline unsigned long dma_alloc_coherent_mask(struct device *dev, 73 gfp_t gfp) 74 { 75 unsigned long dma_mask = 0; 76 77 dma_mask = dev->coherent_dma_mask; 78 if (!dma_mask) 79 dma_mask = (gfp & GFP_DMA) ? DMA_BIT_MASK(24) : DMA_BIT_MASK(32); 80 81 return dma_mask; 82 } 83 84 static inline gfp_t dma_alloc_coherent_gfp_flags(struct device *dev, gfp_t gfp) 85 { 86 unsigned long dma_mask = dma_alloc_coherent_mask(dev, gfp); 87 88 if (dma_mask <= DMA_BIT_MASK(24)) 89 gfp |= GFP_DMA; 90 #ifdef CONFIG_X86_64 91 if (dma_mask <= DMA_BIT_MASK(32) && !(gfp & GFP_DMA)) 92 gfp |= GFP_DMA32; 93 #endif 94 return gfp; 95 } 96 97 static inline void * 98 dma_alloc_coherent(struct device *dev, size_t size, dma_addr_t *dma_handle, 99 gfp_t gfp) 100 { 101 struct dma_map_ops *ops = get_dma_ops(dev); 102 void *memory; 103 104 gfp &= ~(__GFP_DMA | __GFP_HIGHMEM | __GFP_DMA32); 105 106 if (dma_alloc_from_coherent(dev, size, dma_handle, &memory)) 107 return memory; 108 109 if (!dev) { 110 dev = &x86_dma_fallback_dev; 111 gfp |= GFP_DMA; 112 } 113 114 if (!is_device_dma_capable(dev)) 115 return NULL; 116 117 if (!ops->alloc_coherent) 118 return NULL; 119 120 memory = ops->alloc_coherent(dev, size, dma_handle, 121 dma_alloc_coherent_gfp_flags(dev, gfp)); 122 debug_dma_alloc_coherent(dev, size, *dma_handle, memory); 123 124 return memory; 125 } 126 127 static inline void dma_free_coherent(struct device *dev, size_t size, 128 void *vaddr, dma_addr_t bus) 129 { 130 struct dma_map_ops *ops = get_dma_ops(dev); 131 132 WARN_ON(irqs_disabled()); /* for portability */ 133 134 if (dma_release_from_coherent(dev, get_order(size), vaddr)) 135 return; 136 137 debug_dma_free_coherent(dev, size, vaddr, bus); 138 if (ops->free_coherent) 139 ops->free_coherent(dev, size, vaddr, bus); 140 } 141 142 #endif 143