kernel/dma/direct.h

   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 #include <linux/memremap.h>
  12
  13 int dma_direct_get_sgtable(struct device *dev, struct sg_table *sgt,
  14                 void *cpu_addr, dma_addr_t dma_addr, size_t size,
  15                 unsigned long attrs);
  16 bool dma_direct_can_mmap(struct device *dev);
  17 int dma_direct_mmap(struct device *dev, struct vm_area_struct *vma,
  18                 void *cpu_addr, dma_addr_t dma_addr, size_t size,
  19                 unsigned long attrs);
  20 bool dma_direct_need_sync(struct device *dev, dma_addr_t dma_addr);
  21 int dma_direct_map_sg(struct device *dev, struct scatterlist *sgl, int nents,
  22                 enum dma_data_direction dir, unsigned long attrs);
  23 size_t dma_direct_max_mapping_size(struct device *dev);
  24
  25 #if defined(CONFIG_ARCH_HAS_SYNC_DMA_FOR_DEVICE) || \
  26     defined(CONFIG_SWIOTLB)
  27 void dma_direct_sync_sg_for_device(struct device *dev, struct scatterlist *sgl,
  28                 int nents, enum dma_data_direction dir);
  29 #else
  30 static inline void dma_direct_sync_sg_for_device(struct device *dev,
  31                 struct scatterlist *sgl, int nents, enum dma_data_direction dir)
  32 {
  33 }
  34 #endif
  35
  36 #if defined(CONFIG_ARCH_HAS_SYNC_DMA_FOR_CPU) || \
  37     defined(CONFIG_ARCH_HAS_SYNC_DMA_FOR_CPU_ALL) || \
  38     defined(CONFIG_SWIOTLB)
  39 void dma_direct_unmap_sg(struct device *dev, struct scatterlist *sgl,
  40                 int nents, enum dma_data_direction dir, unsigned long attrs);
  41 void dma_direct_sync_sg_for_cpu(struct device *dev,
  42                 struct scatterlist *sgl, int nents, enum dma_data_direction dir);
  43 #else
  44 static inline void dma_direct_unmap_sg(struct device *dev,
  45                 struct scatterlist *sgl, int nents, enum dma_data_direction dir,
  46                 unsigned long attrs)
  47 {
  48 }
  49 static inline void dma_direct_sync_sg_for_cpu(struct device *dev,
  50                 struct scatterlist *sgl, int nents, enum dma_data_direction dir)
  51 {
  52 }
  53 #endif
  54
  55 static inline void dma_direct_sync_single_for_device(struct device *dev,
  56                 dma_addr_t addr, size_t size, enum dma_data_direction dir)
  57 {
  58         phys_addr_t paddr = dma_to_phys(dev, addr);
  59
  60         if (unlikely(is_swiotlb_buffer(dev, paddr)))
  61                 swiotlb_sync_single_for_device(dev, paddr, size, dir);
  62
  63         if (!dev_is_dma_coherent(dev))
  64                 arch_sync_dma_for_device(paddr, size, dir);
  65 }
  66
  67 static inline void dma_direct_sync_single_for_cpu(struct device *dev,
  68                 dma_addr_t addr, size_t size, enum dma_data_direction dir)
  69 {
  70         phys_addr_t paddr = dma_to_phys(dev, addr);
  71
  72         if (!dev_is_dma_coherent(dev)) {
  73                 arch_sync_dma_for_cpu(paddr, size, dir);
  74                 arch_sync_dma_for_cpu_all();
  75         }
  76
  77         if (unlikely(is_swiotlb_buffer(dev, paddr)))
  78                 swiotlb_sync_single_for_cpu(dev, paddr, size, dir);
  79
  80         if (dir == DMA_FROM_DEVICE)
  81                 arch_dma_mark_clean(paddr, size);
  82 }
  83
  84 static inline dma_addr_t dma_direct_map_page(struct device *dev,
  85                 struct page *page, unsigned long offset, size_t size,
  86                 enum dma_data_direction dir, unsigned long attrs)
  87 {
  88         phys_addr_t phys = page_to_phys(page) + offset;
  89         dma_addr_t dma_addr = phys_to_dma(dev, phys);
  90
  91         if (is_swiotlb_force_bounce(dev)) {
  92                 if (is_pci_p2pdma_page(page))
  93                         return DMA_MAPPING_ERROR;
  94                 return swiotlb_map(dev, phys, size, dir, attrs);
  95         }
  96
  97         if (unlikely(!dma_capable(dev, dma_addr, size, true))) {
  98                 if (is_pci_p2pdma_page(page))
  99                         return DMA_MAPPING_ERROR;
 100                 if (is_swiotlb_active(dev))
 101                         return swiotlb_map(dev, phys, size, dir, attrs);
 102
 103                 dev_WARN_ONCE(dev, 1,
 104                              "DMA addr %pad+%zu overflow (mask %llx, bus limit %llx).\n",
 105                              &dma_addr, size, *dev->dma_mask, dev->bus_dma_limit);
 106                 return DMA_MAPPING_ERROR;
 107         }
 108
 109         if (!dev_is_dma_coherent(dev) && !(attrs & DMA_ATTR_SKIP_CPU_SYNC))
 110                 arch_sync_dma_for_device(phys, size, dir);
 111         return dma_addr;
 112 }
 113
 114 static inline void dma_direct_unmap_page(struct device *dev, dma_addr_t addr,
 115                 size_t size, enum dma_data_direction dir, unsigned long attrs)
 116 {
 117         phys_addr_t phys = dma_to_phys(dev, addr);
 118
 119         if (!(attrs & DMA_ATTR_SKIP_CPU_SYNC))
 120                 dma_direct_sync_single_for_cpu(dev, addr, size, dir);
 121
 122         if (unlikely(is_swiotlb_buffer(dev, phys)))
 123                 swiotlb_tbl_unmap_single(dev, phys, size, dir,
 124                                          attrs | DMA_ATTR_SKIP_CPU_SYNC);
 125 }
 126 #endif /* _KERNEL_DMA_DIRECT_H */