LXR linux/arch/x86/include/asm/dma-mapping.h

   1#ifndef _ASM_X86_DMA_MAPPING_H
   2#define _ASM_X86_DMA_MAPPING_H
   3
   4/*
   5 * IOMMU interface. See Documentation/DMA-API-HOWTO.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#include <linux/dma-contiguous.h>
  17
  18#ifdef CONFIG_ISA
  19# define ISA_DMA_BIT_MASK DMA_BIT_MASK(24)
  20#else
  21# define ISA_DMA_BIT_MASK DMA_BIT_MASK(32)
  22#endif
  23
  24#define DMA_ERROR_CODE  0
  25
  26extern int iommu_merge;
  27extern struct device x86_dma_fallback_dev;
  28extern int panic_on_overflow;
  29
  30extern struct dma_map_ops *dma_ops;
  31
  32static inline struct dma_map_ops *get_dma_ops(struct device *dev)
  33{
  34#ifndef CONFIG_X86_DEV_DMA_OPS
  35        return dma_ops;
  36#else
  37        if (unlikely(!dev) || !dev->archdata.dma_ops)
  38                return dma_ops;
  39        else
  40                return dev->archdata.dma_ops;
  41#endif
  42}
  43
  44#include <asm-generic/dma-mapping-common.h>
  45
  46/* Make sure we keep the same behaviour */
  47static inline int dma_mapping_error(struct device *dev, dma_addr_t dma_addr)
  48{
  49        struct dma_map_ops *ops = get_dma_ops(dev);
  50        debug_dma_mapping_error(dev, dma_addr);
  51        if (ops->mapping_error)
  52                return ops->mapping_error(dev, dma_addr);
  53
  54        return (dma_addr == DMA_ERROR_CODE);
  55}
  56
  57#define dma_alloc_noncoherent(d, s, h, f) dma_alloc_coherent(d, s, h, f)
  58#define dma_free_noncoherent(d, s, v, h) dma_free_coherent(d, s, v, h)
  59
  60extern int dma_supported(struct device *hwdev, u64 mask);
  61extern int dma_set_mask(struct device *dev, u64 mask);
  62
  63extern void *dma_generic_alloc_coherent(struct device *dev, size_t size,
  64                                        dma_addr_t *dma_addr, gfp_t flag,
  65                                        struct dma_attrs *attrs);
  66
  67extern void dma_generic_free_coherent(struct device *dev, size_t size,
  68                                      void *vaddr, dma_addr_t dma_addr,
  69                                      struct dma_attrs *attrs);
  70
  71#ifdef CONFIG_X86_DMA_REMAP /* Platform code defines bridge-specific code */
  72extern bool dma_capable(struct device *dev, dma_addr_t addr, size_t size);
  73extern dma_addr_t phys_to_dma(struct device *dev, phys_addr_t paddr);
  74extern phys_addr_t dma_to_phys(struct device *dev, dma_addr_t daddr);
  75#else
  76
  77static inline bool dma_capable(struct device *dev, dma_addr_t addr, size_t size)
  78{
  79        if (!dev->dma_mask)
  80                return 0;
  81
  82        return addr + size - 1 <= *dev->dma_mask;
  83}
  84
  85static inline dma_addr_t phys_to_dma(struct device *dev, phys_addr_t paddr)
  86{
  87        return paddr;
  88}
  89
  90static inline phys_addr_t dma_to_phys(struct device *dev, dma_addr_t daddr)
  91{
  92        return daddr;
  93}
  94#endif /* CONFIG_X86_DMA_REMAP */
  95
  96static inline void
  97dma_cache_sync(struct device *dev, void *vaddr, size_t size,
  98        enum dma_data_direction dir)
  99{
 100        flush_write_buffers();
 101}
 102
 103static inline unsigned long dma_alloc_coherent_mask(struct device *dev,
 104                                                    gfp_t gfp)
 105{
 106        unsigned long dma_mask = 0;
 107
 108        dma_mask = dev->coherent_dma_mask;
 109        if (!dma_mask)
 110                dma_mask = (gfp & GFP_DMA) ? DMA_BIT_MASK(24) : DMA_BIT_MASK(32);
 111
 112        return dma_mask;
 113}
 114
 115static inline gfp_t dma_alloc_coherent_gfp_flags(struct device *dev, gfp_t gfp)
 116{
 117        unsigned long dma_mask = dma_alloc_coherent_mask(dev, gfp);
 118
 119        if (dma_mask <= DMA_BIT_MASK(24))
 120                gfp |= GFP_DMA;
 121#ifdef CONFIG_X86_64
 122        if (dma_mask <= DMA_BIT_MASK(32) && !(gfp & GFP_DMA))
 123                gfp |= GFP_DMA32;
 124#endif
 125       return gfp;
 126}
 127
 128#define dma_alloc_coherent(d,s,h,f)     dma_alloc_attrs(d,s,h,f,NULL)
 129
 130static inline void *
 131dma_alloc_attrs(struct device *dev, size_t size, dma_addr_t *dma_handle,
 132                gfp_t gfp, struct dma_attrs *attrs)
 133{
 134        struct dma_map_ops *ops = get_dma_ops(dev);
 135        void *memory;
 136
 137        gfp &= ~(__GFP_DMA | __GFP_HIGHMEM | __GFP_DMA32);
 138
 139        if (dma_alloc_from_coherent(dev, size, dma_handle, &memory))
 140                return memory;
 141
 142        if (!dev)
 143                dev = &x86_dma_fallback_dev;
 144
 145        if (!is_device_dma_capable(dev))
 146                return NULL;
 147
 148        if (!ops->alloc)
 149                return NULL;
 150
 151        memory = ops->alloc(dev, size, dma_handle,
 152                            dma_alloc_coherent_gfp_flags(dev, gfp), attrs);
 153        debug_dma_alloc_coherent(dev, size, *dma_handle, memory);
 154
 155        return memory;
 156}
 157
 158#define dma_free_coherent(d,s,c,h) dma_free_attrs(d,s,c,h,NULL)
 159
 160static inline void dma_free_attrs(struct device *dev, size_t size,
 161                                  void *vaddr, dma_addr_t bus,
 162                                  struct dma_attrs *attrs)
 163{
 164        struct dma_map_ops *ops = get_dma_ops(dev);
 165
 166        WARN_ON(irqs_disabled());       /* for portability */
 167
 168        if (dma_release_from_coherent(dev, get_order(size), vaddr))
 169                return;
 170
 171        debug_dma_free_coherent(dev, size, vaddr, bus);
 172        if (ops->free)
 173                ops->free(dev, size, vaddr, bus, attrs);
 174}
 175
 176#endif
 177