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             : 
      12             : int 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);
      15             : bool dma_direct_can_mmap(struct device *dev);
      16             : int 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);
      19             : bool dma_direct_need_sync(struct device *dev, dma_addr_t dma_addr);
      20             : int dma_direct_map_sg(struct device *dev, struct scatterlist *sgl, int nents,
      21             :                 enum dma_data_direction dir, unsigned long attrs);
      22             : size_t dma_direct_max_mapping_size(struct device *dev);
      23             : 
      24             : #if defined(CONFIG_ARCH_HAS_SYNC_DMA_FOR_DEVICE) || \
      25             :     defined(CONFIG_SWIOTLB)
      26             : void dma_direct_sync_sg_for_device(struct device *dev, struct scatterlist *sgl,
      27             :                 int nents, enum dma_data_direction dir);
      28             : #else
      29             : static 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)
      38             : void dma_direct_unmap_sg(struct device *dev, struct scatterlist *sgl,
      39             :                 int nents, enum dma_data_direction dir, unsigned long attrs);
      40             : void dma_direct_sync_sg_for_cpu(struct device *dev,
      41             :                 struct scatterlist *sgl, int nents, enum dma_data_direction dir);
      42             : #else
      43             : static 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             : }
      48             : static 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             : 
      54           0 : static 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           0 :         phys_addr_t paddr = dma_to_phys(dev, addr);
      58             : 
      59           0 :         if (unlikely(is_swiotlb_buffer(paddr)))
      60           0 :                 swiotlb_tbl_sync_single(dev, paddr, size, dir, SYNC_FOR_DEVICE);
      61             : 
      62           0 :         if (!dev_is_dma_coherent(dev))
      63           0 :                 arch_sync_dma_for_device(paddr, size, dir);
      64           0 : }
      65             : 
      66           0 : static 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           0 :         phys_addr_t paddr = dma_to_phys(dev, addr);
      70             : 
      71           0 :         if (!dev_is_dma_coherent(dev)) {
      72           0 :                 arch_sync_dma_for_cpu(paddr, size, dir);
      73             :                 arch_sync_dma_for_cpu_all();
      74             :         }
      75             : 
      76           0 :         if (unlikely(is_swiotlb_buffer(paddr)))
      77           0 :                 swiotlb_tbl_sync_single(dev, paddr, size, dir, SYNC_FOR_CPU);
      78             : 
      79           0 :         if (dir == DMA_FROM_DEVICE)
      80           0 :                 arch_dma_mark_clean(paddr, size);
      81           0 : }
      82             : 
      83           0 : static 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           0 :         phys_addr_t phys = page_to_phys(page) + offset;
      88           0 :         dma_addr_t dma_addr = phys_to_dma(dev, phys);
      89             : 
      90           0 :         if (unlikely(swiotlb_force == SWIOTLB_FORCE))
      91           0 :                 return swiotlb_map(dev, phys, size, dir, attrs);
      92             : 
      93           0 :         if (unlikely(!dma_capable(dev, dma_addr, size, true))) {
      94           0 :                 if (swiotlb_force != SWIOTLB_NO_FORCE)
      95           0 :                         return swiotlb_map(dev, phys, size, dir, attrs);
      96             : 
      97           0 :                 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           0 :                 return DMA_MAPPING_ERROR;
     101             :         }
     102             : 
     103           0 :         if (!dev_is_dma_coherent(dev) && !(attrs & DMA_ATTR_SKIP_CPU_SYNC))
     104           0 :                 arch_sync_dma_for_device(phys, size, dir);
     105             :         return dma_addr;
     106             : }
     107             : 
     108           0 : static 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           0 :         phys_addr_t phys = dma_to_phys(dev, addr);
     112             : 
     113           0 :         if (!(attrs & DMA_ATTR_SKIP_CPU_SYNC))
     114           0 :                 dma_direct_sync_single_for_cpu(dev, addr, size, dir);
     115             : 
     116           0 :         if (unlikely(is_swiotlb_buffer(phys)))
     117           0 :                 swiotlb_tbl_unmap_single(dev, phys, size, size, dir, attrs);
     118           0 : }
     119             : #endif /* _KERNEL_DMA_DIRECT_H */