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