Line data    Source code

       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           0 :         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           0 :         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           0 : 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           0 :         phys_addr_t phys = page_to_phys(page) + offset;
      89           0 :         dma_addr_t dma_addr = phys_to_dma(dev, phys);
      90             : 
      91           0 :         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           0 :         if (unlikely(!dma_capable(dev, dma_addr, size, true)) ||
      98             :             dma_kmalloc_needs_bounce(dev, size, dir)) {
      99           0 :                 if (is_pci_p2pdma_page(page))
     100             :                         return DMA_MAPPING_ERROR;
     101           0 :                 if (is_swiotlb_active(dev))
     102             :                         return swiotlb_map(dev, phys, size, dir, attrs);
     103             : 
     104           0 :                 dev_WARN_ONCE(dev, 1,
     105             :                              "DMA addr %pad+%zu overflow (mask %llx, bus limit %llx).\n",
     106             :                              &dma_addr, size, *dev->dma_mask, dev->bus_dma_limit);
     107             :                 return DMA_MAPPING_ERROR;
     108             :         }
     109             : 
     110             :         if (!dev_is_dma_coherent(dev) && !(attrs & DMA_ATTR_SKIP_CPU_SYNC))
     111             :                 arch_sync_dma_for_device(phys, size, dir);
     112             :         return dma_addr;
     113             : }
     114             : 
     115           0 : static inline void dma_direct_unmap_page(struct device *dev, dma_addr_t addr,
     116             :                 size_t size, enum dma_data_direction dir, unsigned long attrs)
     117             : {
     118           0 :         phys_addr_t phys = dma_to_phys(dev, addr);
     119             : 
     120           0 :         if (!(attrs & DMA_ATTR_SKIP_CPU_SYNC))
     121           0 :                 dma_direct_sync_single_for_cpu(dev, addr, size, dir);
     122             : 
     123           0 :         if (unlikely(is_swiotlb_buffer(dev, phys)))
     124             :                 swiotlb_tbl_unmap_single(dev, phys, size, dir,
     125             :                                          attrs | DMA_ATTR_SKIP_CPU_SYNC);
     126           0 : }
     127             : #endif /* _KERNEL_DMA_DIRECT_H */