include/linux/dma-iommu.h

   1 /*
   2  * Copyright (C) 2014-2015 ARM Ltd.
   3  *
   4  * This program is free software; you can redistribute it and/or modify
   5  * it under the terms of the GNU General Public License version 2 as
   6  * published by the Free Software Foundation.
   7  *
   8  * This program is distributed in the hope that it will be useful,
   9  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  10  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  11  * GNU General Public License for more details.
  12  *
  13  * You should have received a copy of the GNU General Public License
  14  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  15  */
  16 #ifndef __DMA_IOMMU_H
  17 #define __DMA_IOMMU_H
  18
  19 #ifdef __KERNEL__
  20 #include <asm/errno.h>
  21
  22 #ifdef CONFIG_IOMMU_DMA
  23 #include <linux/iommu.h>
  24
  25 int iommu_dma_init(void);
  26
  27 /* Domain management interface for IOMMU drivers */
  28 int iommu_get_dma_cookie(struct iommu_domain *domain);
  29 void iommu_put_dma_cookie(struct iommu_domain *domain);
  30
  31 /* Setup call for arch DMA mapping code */
  32 int iommu_dma_init_domain(struct iommu_domain *domain, dma_addr_t base, u64 size);
  33
  34 /* General helpers for DMA-API <-> IOMMU-API interaction */
  35 int dma_direction_to_prot(enum dma_data_direction dir, bool coherent);
  36
  37 /*
  38  * These implement the bulk of the relevant DMA mapping callbacks, but require
  39  * the arch code to take care of attributes and cache maintenance
  40  */
  41 struct page **iommu_dma_alloc(struct device *dev, size_t size,
  42                 gfp_t gfp, int prot, dma_addr_t *handle,
  43                 void (*flush_page)(struct device *, const void *, phys_addr_t));
  44 void iommu_dma_free(struct device *dev, struct page **pages, size_t size,
  45                 dma_addr_t *handle);
  46
  47 int iommu_dma_mmap(struct page **pages, size_t size, struct vm_area_struct *vma);
  48
  49 dma_addr_t iommu_dma_map_page(struct device *dev, struct page *page,
  50                 unsigned long offset, size_t size, int prot);
  51 int iommu_dma_map_sg(struct device *dev, struct scatterlist *sg,
  52                 int nents, int prot);
  53
  54 /*
  55  * Arch code with no special attribute handling may use these
  56  * directly as DMA mapping callbacks for simplicity
  57  */
  58 void iommu_dma_unmap_page(struct device *dev, dma_addr_t handle, size_t size,
  59                 enum dma_data_direction dir, struct dma_attrs *attrs);
  60 void iommu_dma_unmap_sg(struct device *dev, struct scatterlist *sg, int nents,
  61                 enum dma_data_direction dir, struct dma_attrs *attrs);
  62 int iommu_dma_supported(struct device *dev, u64 mask);
  63 int iommu_dma_mapping_error(struct device *dev, dma_addr_t dma_addr);
  64
  65 #else
  66
  67 struct iommu_domain;
  68
  69 static inline int iommu_dma_init(void)
  70 {
  71         return 0;
  72 }
  73
  74 static inline int iommu_get_dma_cookie(struct iommu_domain *domain)
  75 {
  76         return -ENODEV;
  77 }
  78
  79 static inline void iommu_put_dma_cookie(struct iommu_domain *domain)
  80 {
  81 }
  82
  83 #endif  /* CONFIG_IOMMU_DMA */
  84 #endif  /* __KERNEL__ */
  85 #endif  /* __DMA_IOMMU_H */