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