LXR linux/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
  12int 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);
  15bool dma_direct_can_mmap(struct device *dev);
  16int 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);
  19bool dma_direct_need_sync(struct device *dev, dma_addr_t dma_addr);
  20int dma_direct_map_sg(struct device *dev, struct scatterlist *sgl, int nents,
  21                enum dma_data_direction dir, unsigned long attrs);
  22size_t dma_direct_max_mapping_size(struct device *dev);
  23
  24#if defined(CONFIG_ARCH_HAS_SYNC_DMA_FOR_DEVICE) || \
  25    defined(CONFIG_SWIOTLB)
  26void dma_direct_sync_sg_for_device(struct device *dev, struct scatterlist *sgl,
  27                int nents, enum dma_data_direction dir);
  28#else
  29static 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)
  38void dma_direct_unmap_sg(struct device *dev, struct scatterlist *sgl,
  39                int nents, enum dma_data_direction dir, unsigned long attrs);
  40void dma_direct_sync_sg_for_cpu(struct device *dev,
  41                struct scatterlist *sgl, int nents, enum dma_data_direction dir);
  42#else
  43static 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}
  48static 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
  54static 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
  66static 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
  83static 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
 108static 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, attrs);
 118}
 119#endif /* _KERNEL_DMA_DIRECT_H */
 120