include/linux/iommu.h

   1 /*
   2  * Copyright (C) 2007-2008 Advanced Micro Devices, Inc.
   3  * Author: Joerg Roedel <joerg.roedel@amd.com>
   4  *
   5  * This program is free software; you can redistribute it and/or modify it
   6  * under the terms of the GNU General Public License version 2 as published
   7  * by the Free Software Foundation.
   8  *
   9  * This program is distributed in the hope that it will be useful,
  10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12  * GNU General Public License for more details.
  13  *
  14  * You should have received a copy of the GNU General Public License
  15  * along with this program; if not, write to the Free Software
  16  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307 USA
  17  */
  18
  19 #ifndef __LINUX_IOMMU_H
  20 #define __LINUX_IOMMU_H
  21
  22 #include <linux/errno.h>
  23
  24 #define IOMMU_READ      (1)
  25 #define IOMMU_WRITE     (2)
  26 #define IOMMU_CACHE     (4) /* DMA cache coherency */
  27
  28 struct device;
  29 struct iommu_domain;
  30
  31 /* iommu fault flags */
  32 #define IOMMU_FAULT_READ        0x0
  33 #define IOMMU_FAULT_WRITE       0x1
  34
  35 typedef int (*iommu_fault_handler_t)(struct iommu_domain *,
  36                                 struct device *, unsigned long, int);
  37
  38 struct iommu_domain {
  39         void *priv;
  40         iommu_fault_handler_t handler;
  41 };
  42
  43 #define IOMMU_CAP_CACHE_COHERENCY       0x1
  44 #define IOMMU_CAP_INTR_REMAP            0x2     /* isolates device intrs */
  45
  46 struct iommu_ops {
  47         int (*domain_init)(struct iommu_domain *domain);
  48         void (*domain_destroy)(struct iommu_domain *domain);
  49         int (*attach_dev)(struct iommu_domain *domain, struct device *dev);
  50         void (*detach_dev)(struct iommu_domain *domain, struct device *dev);
  51         int (*map)(struct iommu_domain *domain, unsigned long iova,
  52                    phys_addr_t paddr, int gfp_order, int prot);
  53         int (*unmap)(struct iommu_domain *domain, unsigned long iova,
  54                      int gfp_order);
  55         phys_addr_t (*iova_to_phys)(struct iommu_domain *domain,
  56                                     unsigned long iova);
  57         int (*domain_has_cap)(struct iommu_domain *domain,
  58                               unsigned long cap);
  59 };
  60
  61 #ifdef CONFIG_IOMMU_API
  62
  63 extern void register_iommu(struct iommu_ops *ops);
  64 extern bool iommu_found(void);
  65 extern struct iommu_domain *iommu_domain_alloc(void);
  66 extern void iommu_domain_free(struct iommu_domain *domain);
  67 extern int iommu_attach_device(struct iommu_domain *domain,
  68                                struct device *dev);
  69 extern void iommu_detach_device(struct iommu_domain *domain,
  70                                 struct device *dev);
  71 extern int iommu_map(struct iommu_domain *domain, unsigned long iova,
  72                      phys_addr_t paddr, int gfp_order, int prot);
  73 extern int iommu_unmap(struct iommu_domain *domain, unsigned long iova,
  74                        int gfp_order);
  75 extern phys_addr_t iommu_iova_to_phys(struct iommu_domain *domain,
  76                                       unsigned long iova);
  77 extern int iommu_domain_has_cap(struct iommu_domain *domain,
  78                                 unsigned long cap);
  79 extern void iommu_set_fault_handler(struct iommu_domain *domain,
  80                                         iommu_fault_handler_t handler);
  81
  82 /**
  83  * report_iommu_fault() - report about an IOMMU fault to the IOMMU framework
  84  * @domain: the iommu domain where the fault has happened
  85  * @dev: the device where the fault has happened
  86  * @iova: the faulting address
  87  * @flags: mmu fault flags (e.g. IOMMU_FAULT_READ/IOMMU_FAULT_WRITE/...)
  88  *
  89  * This function should be called by the low-level IOMMU implementations
  90  * whenever IOMMU faults happen, to allow high-level users, that are
  91  * interested in such events, to know about them.
  92  *
  93  * This event may be useful for several possible use cases:
  94  * - mere logging of the event
  95  * - dynamic TLB/PTE loading
  96  * - if restarting of the faulting device is required
  97  *
  98  * Returns 0 on success and an appropriate error code otherwise (if dynamic
  99  * PTE/TLB loading will one day be supported, implementations will be able
 100  * to tell whether it succeeded or not according to this return value).
 101  */
 102 static inline int report_iommu_fault(struct iommu_domain *domain,
 103                 struct device *dev, unsigned long iova, int flags)
 104 {
 105         int ret = 0;
 106
 107         /*
 108          * if upper layers showed interest and installed a fault handler,
 109          * invoke it.
 110          */
 111         if (domain->handler)
 112                 ret = domain->handler(domain, dev, iova, flags);
 113
 114         return ret;
 115 }
 116
 117 #else /* CONFIG_IOMMU_API */
 118
 119 static inline void register_iommu(struct iommu_ops *ops)
 120 {
 121 }
 122
 123 static inline bool iommu_found(void)
 124 {
 125         return false;
 126 }
 127
 128 static inline struct iommu_domain *iommu_domain_alloc(void)
 129 {
 130         return NULL;
 131 }
 132
 133 static inline void iommu_domain_free(struct iommu_domain *domain)
 134 {
 135 }
 136
 137 static inline int iommu_attach_device(struct iommu_domain *domain,
 138                                       struct device *dev)
 139 {
 140         return -ENODEV;
 141 }
 142
 143 static inline void iommu_detach_device(struct iommu_domain *domain,
 144                                        struct device *dev)
 145 {
 146 }
 147
 148 static inline int iommu_map(struct iommu_domain *domain, unsigned long iova,
 149                             phys_addr_t paddr, int gfp_order, int prot)
 150 {
 151         return -ENODEV;
 152 }
 153
 154 static inline int iommu_unmap(struct iommu_domain *domain, unsigned long iova,
 155                               int gfp_order)
 156 {
 157         return -ENODEV;
 158 }
 159
 160 static inline phys_addr_t iommu_iova_to_phys(struct iommu_domain *domain,
 161                                              unsigned long iova)
 162 {
 163         return 0;
 164 }
 165
 166 static inline int domain_has_cap(struct iommu_domain *domain,
 167                                  unsigned long cap)
 168 {
 169         return 0;
 170 }
 171
 172 static inline void iommu_set_fault_handler(struct iommu_domain *domain,
 173                                         iommu_fault_handler_t handler)
 174 {
 175 }
 176
 177 #endif /* CONFIG_IOMMU_API */
 178
 179 #endif /* __LINUX_IOMMU_H */