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/dma-mapping.h>
  24 #include <linux/iommu.h>
  25 #include <linux/msi.h>
  26
  27 int iommu_dma_init(void);
  28
  29 /* Domain management interface for IOMMU drivers */
  30 int iommu_get_dma_cookie(struct iommu_domain *domain);
  31 int iommu_get_msi_cookie(struct iommu_domain *domain, dma_addr_t base);
  32 void iommu_put_dma_cookie(struct iommu_domain *domain);
  33
  34 /* Setup call for arch DMA mapping code */
  35 int iommu_dma_init_domain(struct iommu_domain *domain, dma_addr_t base,
  36                 u64 size, struct device *dev);
  37
  38 /* General helpers for DMA-API <-> IOMMU-API interaction */
  39 int dma_info_to_prot(enum dma_data_direction dir, bool coherent,
  40                      unsigned long attrs);
  41
  42 /*
  43  * These implement the bulk of the relevant DMA mapping callbacks, but require
  44  * the arch code to take care of attributes and cache maintenance
  45  */
  46 struct page **iommu_dma_alloc(struct device *dev, size_t size, gfp_t gfp,
  47                 unsigned long attrs, int prot, dma_addr_t *handle,
  48                 void (*flush_page)(struct device *, const void *, phys_addr_t));
  49 void iommu_dma_free(struct device *dev, struct page **pages, size_t size,
  50                 dma_addr_t *handle);
  51
  52 int iommu_dma_mmap(struct page **pages, size_t size, struct vm_area_struct *vma);
  53
  54 dma_addr_t iommu_dma_map_page(struct device *dev, struct page *page,
  55                 unsigned long offset, size_t size, int prot);
  56 int iommu_dma_map_sg(struct device *dev, struct scatterlist *sg,
  57                 int nents, int prot);
  58
  59 /*
  60  * Arch code with no special attribute handling may use these
  61  * directly as DMA mapping callbacks for simplicity
  62  */
  63 void iommu_dma_unmap_page(struct device *dev, dma_addr_t handle, size_t size,
  64                 enum dma_data_direction dir, unsigned long attrs);
  65 void iommu_dma_unmap_sg(struct device *dev, struct scatterlist *sg, int nents,
  66                 enum dma_data_direction dir, unsigned long attrs);
  67 dma_addr_t iommu_dma_map_resource(struct device *dev, phys_addr_t phys,
  68                 size_t size, enum dma_data_direction dir, unsigned long attrs);
  69 void iommu_dma_unmap_resource(struct device *dev, dma_addr_t handle,
  70                 size_t size, enum dma_data_direction dir, unsigned long attrs);
  71 int iommu_dma_mapping_error(struct device *dev, dma_addr_t dma_addr);
  72
  73 /* The DMA API isn't _quite_ the whole story, though... */
  74 void iommu_dma_map_msi_msg(int irq, struct msi_msg *msg);
  75 void iommu_dma_get_resv_regions(struct device *dev, struct list_head *list);
  76
  77 #else
  78
  79 struct iommu_domain;
  80 struct msi_msg;
  81 struct device;
  82
  83 static inline int iommu_dma_init(void)
  84 {
  85         return 0;
  86 }
  87
  88 static inline int iommu_get_dma_cookie(struct iommu_domain *domain)
  89 {
  90         return -ENODEV;
  91 }
  92
  93 static inline int iommu_get_msi_cookie(struct iommu_domain *domain, dma_addr_t base)
  94 {
  95         return -ENODEV;
  96 }
  97
  98 static inline void iommu_put_dma_cookie(struct iommu_domain *domain)
  99 {
 100 }
 101
 102 static inline void iommu_dma_map_msi_msg(int irq, struct msi_msg *msg)
 103 {
 104 }
 105
 106 static inline void iommu_dma_get_resv_regions(struct device *dev, struct list_head *list)
 107 {
 108 }
 109
 110 #endif  /* CONFIG_IOMMU_DMA */
 111 #endif  /* __KERNEL__ */
 112 #endif  /* __DMA_IOMMU_H */