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 iommu_ops;
  29 struct bus_type;
  30 struct device;
  31 struct iommu_domain;
  32
  33 /* iommu fault flags */
  34 #define IOMMU_FAULT_READ        0x0
  35 #define IOMMU_FAULT_WRITE       0x1
  36
  37 typedef int (*iommu_fault_handler_t)(struct iommu_domain *,
  38                         struct device *, unsigned long, int, void *);
  39
  40 struct iommu_domain {
  41         struct iommu_ops *ops;
  42         void *priv;
  43         iommu_fault_handler_t handler;
  44         void *handler_token;
  45 };
  46
  47 #define IOMMU_CAP_CACHE_COHERENCY       0x1
  48 #define IOMMU_CAP_INTR_REMAP            0x2     /* isolates device intrs */
  49
  50 #ifdef CONFIG_IOMMU_API
  51
  52 /**
  53  * struct iommu_ops - iommu ops and capabilities
  54  * @domain_init: init iommu domain
  55  * @domain_destroy: destroy iommu domain
  56  * @attach_dev: attach device to an iommu domain
  57  * @detach_dev: detach device from an iommu domain
  58  * @map: map a physically contiguous memory region to an iommu domain
  59  * @unmap: unmap a physically contiguous memory region from an iommu domain
  60  * @iova_to_phys: translate iova to physical address
  61  * @domain_has_cap: domain capabilities query
  62  * @commit: commit iommu domain
  63  * @pgsize_bitmap: bitmap of supported page sizes
  64  */
  65 struct iommu_ops {
  66         int (*domain_init)(struct iommu_domain *domain);
  67         void (*domain_destroy)(struct iommu_domain *domain);
  68         int (*attach_dev)(struct iommu_domain *domain, struct device *dev);
  69         void (*detach_dev)(struct iommu_domain *domain, struct device *dev);
  70         int (*map)(struct iommu_domain *domain, unsigned long iova,
  71                    phys_addr_t paddr, size_t size, int prot);
  72         size_t (*unmap)(struct iommu_domain *domain, unsigned long iova,
  73                      size_t size);
  74         phys_addr_t (*iova_to_phys)(struct iommu_domain *domain,
  75                                     unsigned long iova);
  76         int (*domain_has_cap)(struct iommu_domain *domain,
  77                               unsigned long cap);
  78         int (*device_group)(struct device *dev, unsigned int *groupid);
  79         unsigned long pgsize_bitmap;
  80 };
  81
  82 extern int bus_set_iommu(struct bus_type *bus, struct iommu_ops *ops);
  83 extern bool iommu_present(struct bus_type *bus);
  84 extern struct iommu_domain *iommu_domain_alloc(struct bus_type *bus);
  85 extern void iommu_domain_free(struct iommu_domain *domain);
  86 extern int iommu_attach_device(struct iommu_domain *domain,
  87                                struct device *dev);
  88 extern void iommu_detach_device(struct iommu_domain *domain,
  89                                 struct device *dev);
  90 extern int iommu_map(struct iommu_domain *domain, unsigned long iova,
  91                      phys_addr_t paddr, size_t size, int prot);
  92 extern size_t iommu_unmap(struct iommu_domain *domain, unsigned long iova,
  93                        size_t size);
  94 extern phys_addr_t iommu_iova_to_phys(struct iommu_domain *domain,
  95                                       unsigned long iova);
  96 extern int iommu_domain_has_cap(struct iommu_domain *domain,
  97                                 unsigned long cap);
  98 extern void iommu_set_fault_handler(struct iommu_domain *domain,
  99                         iommu_fault_handler_t handler, void *token);
 100 extern int iommu_device_group(struct device *dev, unsigned int *groupid);
 101
 102 /**
 103  * report_iommu_fault() - report about an IOMMU fault to the IOMMU framework
 104  * @domain: the iommu domain where the fault has happened
 105  * @dev: the device where the fault has happened
 106  * @iova: the faulting address
 107  * @flags: mmu fault flags (e.g. IOMMU_FAULT_READ/IOMMU_FAULT_WRITE/...)
 108  *
 109  * This function should be called by the low-level IOMMU implementations
 110  * whenever IOMMU faults happen, to allow high-level users, that are
 111  * interested in such events, to know about them.
 112  *
 113  * This event may be useful for several possible use cases:
 114  * - mere logging of the event
 115  * - dynamic TLB/PTE loading
 116  * - if restarting of the faulting device is required
 117  *
 118  * Returns 0 on success and an appropriate error code otherwise (if dynamic
 119  * PTE/TLB loading will one day be supported, implementations will be able
 120  * to tell whether it succeeded or not according to this return value).
 121  *
 122  * Specifically, -ENOSYS is returned if a fault handler isn't installed
 123  * (though fault handlers can also return -ENOSYS, in case they want to
 124  * elicit the default behavior of the IOMMU drivers).
 125  */
 126 static inline int report_iommu_fault(struct iommu_domain *domain,
 127                 struct device *dev, unsigned long iova, int flags)
 128 {
 129         int ret = -ENOSYS;
 130
 131         /*
 132          * if upper layers showed interest and installed a fault handler,
 133          * invoke it.
 134          */
 135         if (domain->handler)
 136                 ret = domain->handler(domain, dev, iova, flags,
 137                                                 domain->handler_token);
 138
 139         return ret;
 140 }
 141
 142 #else /* CONFIG_IOMMU_API */
 143
 144 struct iommu_ops {};
 145
 146 static inline bool iommu_present(struct bus_type *bus)
 147 {
 148         return false;
 149 }
 150
 151 static inline struct iommu_domain *iommu_domain_alloc(struct bus_type *bus)
 152 {
 153         return NULL;
 154 }
 155
 156 static inline void iommu_domain_free(struct iommu_domain *domain)
 157 {
 158 }
 159
 160 static inline int iommu_attach_device(struct iommu_domain *domain,
 161                                       struct device *dev)
 162 {
 163         return -ENODEV;
 164 }
 165
 166 static inline void iommu_detach_device(struct iommu_domain *domain,
 167                                        struct device *dev)
 168 {
 169 }
 170
 171 static inline int iommu_map(struct iommu_domain *domain, unsigned long iova,
 172                             phys_addr_t paddr, int gfp_order, int prot)
 173 {
 174         return -ENODEV;
 175 }
 176
 177 static inline int iommu_unmap(struct iommu_domain *domain, unsigned long iova,
 178                               int gfp_order)
 179 {
 180         return -ENODEV;
 181 }
 182
 183 static inline phys_addr_t iommu_iova_to_phys(struct iommu_domain *domain,
 184                                              unsigned long iova)
 185 {
 186         return 0;
 187 }
 188
 189 static inline int domain_has_cap(struct iommu_domain *domain,
 190                                  unsigned long cap)
 191 {
 192         return 0;
 193 }
 194
 195 static inline void iommu_set_fault_handler(struct iommu_domain *domain,
 196                                 iommu_fault_handler_t handler, void *token)
 197 {
 198 }
 199
 200 static inline int iommu_device_group(struct device *dev, unsigned int *groupid)
 201 {
 202         return -ENODEV;
 203 }
 204
 205 #endif /* CONFIG_IOMMU_API */
 206
 207 #endif /* __LINUX_IOMMU_H */