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 #include <linux/err.h>
  24 #include <linux/of.h>
  25 #include <linux/types.h>
  26 #include <linux/scatterlist.h>
  27 #include <trace/events/iommu.h>
  28
  29 #define IOMMU_READ      (1 << 0)
  30 #define IOMMU_WRITE     (1 << 1)
  31 #define IOMMU_CACHE     (1 << 2) /* DMA cache coherency */
  32 #define IOMMU_NOEXEC    (1 << 3)
  33 #define IOMMU_MMIO      (1 << 4) /* e.g. things like MSI doorbells */
  34
  35 struct iommu_ops;
  36 struct iommu_group;
  37 struct bus_type;
  38 struct device;
  39 struct iommu_domain;
  40 struct notifier_block;
  41
  42 /* iommu fault flags */
  43 #define IOMMU_FAULT_READ        0x0
  44 #define IOMMU_FAULT_WRITE       0x1
  45
  46 typedef int (*iommu_fault_handler_t)(struct iommu_domain *,
  47                         struct device *, unsigned long, int, void *);
  48
  49 struct iommu_domain_geometry {
  50         dma_addr_t aperture_start; /* First address that can be mapped    */
  51         dma_addr_t aperture_end;   /* Last address that can be mapped     */
  52         bool force_aperture;       /* DMA only allowed in mappable range? */
  53 };
  54
  55 /* Domain feature flags */
  56 #define __IOMMU_DOMAIN_PAGING   (1U << 0)  /* Support for iommu_map/unmap */
  57 #define __IOMMU_DOMAIN_DMA_API  (1U << 1)  /* Domain for use in DMA-API
  58                                               implementation              */
  59 #define __IOMMU_DOMAIN_PT       (1U << 2)  /* Domain is identity mapped   */
  60
  61 /*
  62  * This are the possible domain-types
  63  *
  64  *      IOMMU_DOMAIN_BLOCKED    - All DMA is blocked, can be used to isolate
  65  *                                devices
  66  *      IOMMU_DOMAIN_IDENTITY   - DMA addresses are system physical addresses
  67  *      IOMMU_DOMAIN_UNMANAGED  - DMA mappings managed by IOMMU-API user, used
  68  *                                for VMs
  69  *      IOMMU_DOMAIN_DMA        - Internally used for DMA-API implementations.
  70  *                                This flag allows IOMMU drivers to implement
  71  *                                certain optimizations for these domains
  72  */
  73 #define IOMMU_DOMAIN_BLOCKED    (0U)
  74 #define IOMMU_DOMAIN_IDENTITY   (__IOMMU_DOMAIN_PT)
  75 #define IOMMU_DOMAIN_UNMANAGED  (__IOMMU_DOMAIN_PAGING)
  76 #define IOMMU_DOMAIN_DMA        (__IOMMU_DOMAIN_PAGING |        \
  77                                  __IOMMU_DOMAIN_DMA_API)
  78
  79 struct iommu_domain {
  80         unsigned type;
  81         const struct iommu_ops *ops;
  82         unsigned long pgsize_bitmap;    /* Bitmap of page sizes in use */
  83         iommu_fault_handler_t handler;
  84         void *handler_token;
  85         struct iommu_domain_geometry geometry;
  86         void *iova_cookie;
  87 };
  88
  89 enum iommu_cap {
  90         IOMMU_CAP_CACHE_COHERENCY,      /* IOMMU can enforce cache coherent DMA
  91                                            transactions */
  92         IOMMU_CAP_INTR_REMAP,           /* IOMMU supports interrupt isolation */
  93         IOMMU_CAP_NOEXEC,               /* IOMMU_NOEXEC flag */
  94 };
  95
  96 /*
  97  * Following constraints are specifc to FSL_PAMUV1:
  98  *  -aperture must be power of 2, and naturally aligned
  99  *  -number of windows must be power of 2, and address space size
 100  *   of each window is determined by aperture size / # of windows
 101  *  -the actual size of the mapped region of a window must be power
 102  *   of 2 starting with 4KB and physical address must be naturally
 103  *   aligned.
 104  * DOMAIN_ATTR_FSL_PAMUV1 corresponds to the above mentioned contraints.
 105  * The caller can invoke iommu_domain_get_attr to check if the underlying
 106  * iommu implementation supports these constraints.
 107  */
 108
 109 enum iommu_attr {
 110         DOMAIN_ATTR_GEOMETRY,
 111         DOMAIN_ATTR_PAGING,
 112         DOMAIN_ATTR_WINDOWS,
 113         DOMAIN_ATTR_FSL_PAMU_STASH,
 114         DOMAIN_ATTR_FSL_PAMU_ENABLE,
 115         DOMAIN_ATTR_FSL_PAMUV1,
 116         DOMAIN_ATTR_NESTING,    /* two stages of translation */
 117         DOMAIN_ATTR_MAX,
 118 };
 119
 120 /* These are the possible reserved region types */
 121 #define IOMMU_RESV_DIRECT       (1 << 0)
 122 #define IOMMU_RESV_RESERVED     (1 << 1)
 123 #define IOMMU_RESV_MSI          (1 << 2)
 124
 125 /**
 126  * struct iommu_resv_region - descriptor for a reserved memory region
 127  * @list: Linked list pointers
 128  * @start: System physical start address of the region
 129  * @length: Length of the region in bytes
 130  * @prot: IOMMU Protection flags (READ/WRITE/...)
 131  * @type: Type of the reserved region
 132  */
 133 struct iommu_resv_region {
 134         struct list_head        list;
 135         phys_addr_t             start;
 136         size_t                  length;
 137         int                     prot;
 138         int                     type;
 139 };
 140
 141 #ifdef CONFIG_IOMMU_API
 142
 143 /**
 144  * struct iommu_ops - iommu ops and capabilities
 145  * @capable: check capability
 146  * @domain_alloc: allocate iommu domain
 147  * @domain_free: free iommu domain
 148  * @attach_dev: attach device to an iommu domain
 149  * @detach_dev: detach device from an iommu domain
 150  * @map: map a physically contiguous memory region to an iommu domain
 151  * @unmap: unmap a physically contiguous memory region from an iommu domain
 152  * @map_sg: map a scatter-gather list of physically contiguous memory chunks
 153  * to an iommu domain
 154  * @iova_to_phys: translate iova to physical address
 155  * @add_device: add device to iommu grouping
 156  * @remove_device: remove device from iommu grouping
 157  * @device_group: find iommu group for a particular device
 158  * @domain_get_attr: Query domain attributes
 159  * @domain_set_attr: Change domain attributes
 160  * @get_resv_regions: Request list of reserved regions for a device
 161  * @put_resv_regions: Free list of reserved regions for a device
 162  * @apply_resv_region: Temporary helper call-back for iova reserved ranges
 163  * @domain_window_enable: Configure and enable a particular window for a domain
 164  * @domain_window_disable: Disable a particular window for a domain
 165  * @domain_set_windows: Set the number of windows for a domain
 166  * @domain_get_windows: Return the number of windows for a domain
 167  * @of_xlate: add OF master IDs to iommu grouping
 168  * @pgsize_bitmap: bitmap of all possible supported page sizes
 169  */
 170 struct iommu_ops {
 171         bool (*capable)(enum iommu_cap);
 172
 173         /* Domain allocation and freeing by the iommu driver */
 174         struct iommu_domain *(*domain_alloc)(unsigned iommu_domain_type);
 175         void (*domain_free)(struct iommu_domain *);
 176
 177         int (*attach_dev)(struct iommu_domain *domain, struct device *dev);
 178         void (*detach_dev)(struct iommu_domain *domain, struct device *dev);
 179         int (*map)(struct iommu_domain *domain, unsigned long iova,
 180                    phys_addr_t paddr, size_t size, int prot);
 181         size_t (*unmap)(struct iommu_domain *domain, unsigned long iova,
 182                      size_t size);
 183         size_t (*map_sg)(struct iommu_domain *domain, unsigned long iova,
 184                          struct scatterlist *sg, unsigned int nents, int prot);
 185         phys_addr_t (*iova_to_phys)(struct iommu_domain *domain, dma_addr_t iova);
 186         int (*add_device)(struct device *dev);
 187         void (*remove_device)(struct device *dev);
 188         struct iommu_group *(*device_group)(struct device *dev);
 189         int (*domain_get_attr)(struct iommu_domain *domain,
 190                                enum iommu_attr attr, void *data);
 191         int (*domain_set_attr)(struct iommu_domain *domain,
 192                                enum iommu_attr attr, void *data);
 193
 194         /* Request/Free a list of reserved regions for a device */
 195         void (*get_resv_regions)(struct device *dev, struct list_head *list);
 196         void (*put_resv_regions)(struct device *dev, struct list_head *list);
 197         void (*apply_resv_region)(struct device *dev,
 198                                   struct iommu_domain *domain,
 199                                   struct iommu_resv_region *region);
 200
 201         /* Window handling functions */
 202         int (*domain_window_enable)(struct iommu_domain *domain, u32 wnd_nr,
 203                                     phys_addr_t paddr, u64 size, int prot);
 204         void (*domain_window_disable)(struct iommu_domain *domain, u32 wnd_nr);
 205         /* Set the number of windows per domain */
 206         int (*domain_set_windows)(struct iommu_domain *domain, u32 w_count);
 207         /* Get the number of windows per domain */
 208         u32 (*domain_get_windows)(struct iommu_domain *domain);
 209
 210         int (*of_xlate)(struct device *dev, struct of_phandle_args *args);
 211
 212         unsigned long pgsize_bitmap;
 213 };
 214
 215 #define IOMMU_GROUP_NOTIFY_ADD_DEVICE           1 /* Device added */
 216 #define IOMMU_GROUP_NOTIFY_DEL_DEVICE           2 /* Pre Device removed */
 217 #define IOMMU_GROUP_NOTIFY_BIND_DRIVER          3 /* Pre Driver bind */
 218 #define IOMMU_GROUP_NOTIFY_BOUND_DRIVER         4 /* Post Driver bind */
 219 #define IOMMU_GROUP_NOTIFY_UNBIND_DRIVER        5 /* Pre Driver unbind */
 220 #define IOMMU_GROUP_NOTIFY_UNBOUND_DRIVER       6 /* Post Driver unbind */
 221
 222 extern int bus_set_iommu(struct bus_type *bus, const struct iommu_ops *ops);
 223 extern bool iommu_present(struct bus_type *bus);
 224 extern bool iommu_capable(struct bus_type *bus, enum iommu_cap cap);
 225 extern struct iommu_domain *iommu_domain_alloc(struct bus_type *bus);
 226 extern struct iommu_group *iommu_group_get_by_id(int id);
 227 extern void iommu_domain_free(struct iommu_domain *domain);
 228 extern int iommu_attach_device(struct iommu_domain *domain,
 229                                struct device *dev);
 230 extern void iommu_detach_device(struct iommu_domain *domain,
 231                                 struct device *dev);
 232 extern struct iommu_domain *iommu_get_domain_for_dev(struct device *dev);
 233 extern int iommu_map(struct iommu_domain *domain, unsigned long iova,
 234                      phys_addr_t paddr, size_t size, int prot);
 235 extern size_t iommu_unmap(struct iommu_domain *domain, unsigned long iova,
 236                        size_t size);
 237 extern size_t default_iommu_map_sg(struct iommu_domain *domain, unsigned long iova,
 238                                 struct scatterlist *sg,unsigned int nents,
 239                                 int prot);
 240 extern phys_addr_t iommu_iova_to_phys(struct iommu_domain *domain, dma_addr_t iova);
 241 extern void iommu_set_fault_handler(struct iommu_domain *domain,
 242                         iommu_fault_handler_t handler, void *token);
 243
 244 extern void iommu_get_resv_regions(struct device *dev, struct list_head *list);
 245 extern void iommu_put_resv_regions(struct device *dev, struct list_head *list);
 246 extern int iommu_request_dm_for_dev(struct device *dev);
 247 extern struct iommu_resv_region *
 248 iommu_alloc_resv_region(phys_addr_t start, size_t length, int prot, int type);
 249 extern int iommu_get_group_resv_regions(struct iommu_group *group,
 250                                         struct list_head *head);
 251
 252 extern int iommu_attach_group(struct iommu_domain *domain,
 253                               struct iommu_group *group);
 254 extern void iommu_detach_group(struct iommu_domain *domain,
 255                                struct iommu_group *group);
 256 extern struct iommu_group *iommu_group_alloc(void);
 257 extern void *iommu_group_get_iommudata(struct iommu_group *group);
 258 extern void iommu_group_set_iommudata(struct iommu_group *group,
 259                                       void *iommu_data,
 260                                       void (*release)(void *iommu_data));
 261 extern int iommu_group_set_name(struct iommu_group *group, const char *name);
 262 extern int iommu_group_add_device(struct iommu_group *group,
 263                                   struct device *dev);
 264 extern void iommu_group_remove_device(struct device *dev);
 265 extern int iommu_group_for_each_dev(struct iommu_group *group, void *data,
 266                                     int (*fn)(struct device *, void *));
 267 extern struct iommu_group *iommu_group_get(struct device *dev);
 268 extern struct iommu_group *iommu_group_ref_get(struct iommu_group *group);
 269 extern void iommu_group_put(struct iommu_group *group);
 270 extern int iommu_group_register_notifier(struct iommu_group *group,
 271                                          struct notifier_block *nb);
 272 extern int iommu_group_unregister_notifier(struct iommu_group *group,
 273                                            struct notifier_block *nb);
 274 extern int iommu_group_id(struct iommu_group *group);
 275 extern struct iommu_group *iommu_group_get_for_dev(struct device *dev);
 276 extern struct iommu_domain *iommu_group_default_domain(struct iommu_group *);
 277
 278 extern int iommu_domain_get_attr(struct iommu_domain *domain, enum iommu_attr,
 279                                  void *data);
 280 extern int iommu_domain_set_attr(struct iommu_domain *domain, enum iommu_attr,
 281                                  void *data);
 282 struct device *iommu_device_create(struct device *parent, void *drvdata,
 283                                    const struct attribute_group **groups,
 284                                    const char *fmt, ...) __printf(4, 5);
 285 void iommu_device_destroy(struct device *dev);
 286 int iommu_device_link(struct device *dev, struct device *link);
 287 void iommu_device_unlink(struct device *dev, struct device *link);
 288
 289 /* Window handling function prototypes */
 290 extern int iommu_domain_window_enable(struct iommu_domain *domain, u32 wnd_nr,
 291                                       phys_addr_t offset, u64 size,
 292                                       int prot);
 293 extern void iommu_domain_window_disable(struct iommu_domain *domain, u32 wnd_nr);
 294 /**
 295  * report_iommu_fault() - report about an IOMMU fault to the IOMMU framework
 296  * @domain: the iommu domain where the fault has happened
 297  * @dev: the device where the fault has happened
 298  * @iova: the faulting address
 299  * @flags: mmu fault flags (e.g. IOMMU_FAULT_READ/IOMMU_FAULT_WRITE/...)
 300  *
 301  * This function should be called by the low-level IOMMU implementations
 302  * whenever IOMMU faults happen, to allow high-level users, that are
 303  * interested in such events, to know about them.
 304  *
 305  * This event may be useful for several possible use cases:
 306  * - mere logging of the event
 307  * - dynamic TLB/PTE loading
 308  * - if restarting of the faulting device is required
 309  *
 310  * Returns 0 on success and an appropriate error code otherwise (if dynamic
 311  * PTE/TLB loading will one day be supported, implementations will be able
 312  * to tell whether it succeeded or not according to this return value).
 313  *
 314  * Specifically, -ENOSYS is returned if a fault handler isn't installed
 315  * (though fault handlers can also return -ENOSYS, in case they want to
 316  * elicit the default behavior of the IOMMU drivers).
 317  */
 318 static inline int report_iommu_fault(struct iommu_domain *domain,
 319                 struct device *dev, unsigned long iova, int flags)
 320 {
 321         int ret = -ENOSYS;
 322
 323         /*
 324          * if upper layers showed interest and installed a fault handler,
 325          * invoke it.
 326          */
 327         if (domain->handler)
 328                 ret = domain->handler(domain, dev, iova, flags,
 329                                                 domain->handler_token);
 330
 331         trace_io_page_fault(dev, iova, flags);
 332         return ret;
 333 }
 334
 335 static inline size_t iommu_map_sg(struct iommu_domain *domain,
 336                                   unsigned long iova, struct scatterlist *sg,
 337                                   unsigned int nents, int prot)
 338 {
 339         return domain->ops->map_sg(domain, iova, sg, nents, prot);
 340 }
 341
 342 /* PCI device grouping function */
 343 extern struct iommu_group *pci_device_group(struct device *dev);
 344 /* Generic device grouping function */
 345 extern struct iommu_group *generic_device_group(struct device *dev);
 346
 347 /**
 348  * struct iommu_fwspec - per-device IOMMU instance data
 349  * @ops: ops for this device's IOMMU
 350  * @iommu_fwnode: firmware handle for this device's IOMMU
 351  * @iommu_priv: IOMMU driver private data for this device
 352  * @num_ids: number of associated device IDs
 353  * @ids: IDs which this device may present to the IOMMU
 354  */
 355 struct iommu_fwspec {
 356         const struct iommu_ops  *ops;
 357         struct fwnode_handle    *iommu_fwnode;
 358         void                    *iommu_priv;
 359         unsigned int            num_ids;
 360         u32                     ids[1];
 361 };
 362
 363 int iommu_fwspec_init(struct device *dev, struct fwnode_handle *iommu_fwnode,
 364                       const struct iommu_ops *ops);
 365 void iommu_fwspec_free(struct device *dev);
 366 int iommu_fwspec_add_ids(struct device *dev, u32 *ids, int num_ids);
 367 void iommu_register_instance(struct fwnode_handle *fwnode,
 368                              const struct iommu_ops *ops);
 369 const struct iommu_ops *iommu_get_instance(struct fwnode_handle *fwnode);
 370
 371 #else /* CONFIG_IOMMU_API */
 372
 373 struct iommu_ops {};
 374 struct iommu_group {};
 375 struct iommu_fwspec {};
 376
 377 static inline bool iommu_present(struct bus_type *bus)
 378 {
 379         return false;
 380 }
 381
 382 static inline bool iommu_capable(struct bus_type *bus, enum iommu_cap cap)
 383 {
 384         return false;
 385 }
 386
 387 static inline struct iommu_domain *iommu_domain_alloc(struct bus_type *bus)
 388 {
 389         return NULL;
 390 }
 391
 392 static inline struct iommu_group *iommu_group_get_by_id(int id)
 393 {
 394         return NULL;
 395 }
 396
 397 static inline void iommu_domain_free(struct iommu_domain *domain)
 398 {
 399 }
 400
 401 static inline int iommu_attach_device(struct iommu_domain *domain,
 402                                       struct device *dev)
 403 {
 404         return -ENODEV;
 405 }
 406
 407 static inline void iommu_detach_device(struct iommu_domain *domain,
 408                                        struct device *dev)
 409 {
 410 }
 411
 412 static inline struct iommu_domain *iommu_get_domain_for_dev(struct device *dev)
 413 {
 414         return NULL;
 415 }
 416
 417 static inline int iommu_map(struct iommu_domain *domain, unsigned long iova,
 418                             phys_addr_t paddr, int gfp_order, int prot)
 419 {
 420         return -ENODEV;
 421 }
 422
 423 static inline int iommu_unmap(struct iommu_domain *domain, unsigned long iova,
 424                               int gfp_order)
 425 {
 426         return -ENODEV;
 427 }
 428
 429 static inline size_t iommu_map_sg(struct iommu_domain *domain,
 430                                   unsigned long iova, struct scatterlist *sg,
 431                                   unsigned int nents, int prot)
 432 {
 433         return -ENODEV;
 434 }
 435
 436 static inline int iommu_domain_window_enable(struct iommu_domain *domain,
 437                                              u32 wnd_nr, phys_addr_t paddr,
 438                                              u64 size, int prot)
 439 {
 440         return -ENODEV;
 441 }
 442
 443 static inline void iommu_domain_window_disable(struct iommu_domain *domain,
 444                                                u32 wnd_nr)
 445 {
 446 }
 447
 448 static inline phys_addr_t iommu_iova_to_phys(struct iommu_domain *domain, dma_addr_t iova)
 449 {
 450         return 0;
 451 }
 452
 453 static inline void iommu_set_fault_handler(struct iommu_domain *domain,
 454                                 iommu_fault_handler_t handler, void *token)
 455 {
 456 }
 457
 458 static inline void iommu_get_resv_regions(struct device *dev,
 459                                         struct list_head *list)
 460 {
 461 }
 462
 463 static inline void iommu_put_resv_regions(struct device *dev,
 464                                         struct list_head *list)
 465 {
 466 }
 467
 468 static inline int iommu_get_group_resv_regions(struct iommu_group *group,
 469                                                struct list_head *head)
 470 {
 471         return -ENODEV;
 472 }
 473
 474 static inline int iommu_request_dm_for_dev(struct device *dev)
 475 {
 476         return -ENODEV;
 477 }
 478
 479 static inline int iommu_attach_group(struct iommu_domain *domain,
 480                                      struct iommu_group *group)
 481 {
 482         return -ENODEV;
 483 }
 484
 485 static inline void iommu_detach_group(struct iommu_domain *domain,
 486                                       struct iommu_group *group)
 487 {
 488 }
 489
 490 static inline struct iommu_group *iommu_group_alloc(void)
 491 {
 492         return ERR_PTR(-ENODEV);
 493 }
 494
 495 static inline void *iommu_group_get_iommudata(struct iommu_group *group)
 496 {
 497         return NULL;
 498 }
 499
 500 static inline void iommu_group_set_iommudata(struct iommu_group *group,
 501                                              void *iommu_data,
 502                                              void (*release)(void *iommu_data))
 503 {
 504 }
 505
 506 static inline int iommu_group_set_name(struct iommu_group *group,
 507                                        const char *name)
 508 {
 509         return -ENODEV;
 510 }
 511
 512 static inline int iommu_group_add_device(struct iommu_group *group,
 513                                          struct device *dev)
 514 {
 515         return -ENODEV;
 516 }
 517
 518 static inline void iommu_group_remove_device(struct device *dev)
 519 {
 520 }
 521
 522 static inline int iommu_group_for_each_dev(struct iommu_group *group,
 523                                            void *data,
 524                                            int (*fn)(struct device *, void *))
 525 {
 526         return -ENODEV;
 527 }
 528
 529 static inline struct iommu_group *iommu_group_get(struct device *dev)
 530 {
 531         return NULL;
 532 }
 533
 534 static inline void iommu_group_put(struct iommu_group *group)
 535 {
 536 }
 537
 538 static inline int iommu_group_register_notifier(struct iommu_group *group,
 539                                                 struct notifier_block *nb)
 540 {
 541         return -ENODEV;
 542 }
 543
 544 static inline int iommu_group_unregister_notifier(struct iommu_group *group,
 545                                                   struct notifier_block *nb)
 546 {
 547         return 0;
 548 }
 549
 550 static inline int iommu_group_id(struct iommu_group *group)
 551 {
 552         return -ENODEV;
 553 }
 554
 555 static inline int iommu_domain_get_attr(struct iommu_domain *domain,
 556                                         enum iommu_attr attr, void *data)
 557 {
 558         return -EINVAL;
 559 }
 560
 561 static inline int iommu_domain_set_attr(struct iommu_domain *domain,
 562                                         enum iommu_attr attr, void *data)
 563 {
 564         return -EINVAL;
 565 }
 566
 567 static inline struct device *iommu_device_create(struct device *parent,
 568                                         void *drvdata,
 569                                         const struct attribute_group **groups,
 570                                         const char *fmt, ...)
 571 {
 572         return ERR_PTR(-ENODEV);
 573 }
 574
 575 static inline void iommu_device_destroy(struct device *dev)
 576 {
 577 }
 578
 579 static inline int iommu_device_link(struct device *dev, struct device *link)
 580 {
 581         return -EINVAL;
 582 }
 583
 584 static inline void iommu_device_unlink(struct device *dev, struct device *link)
 585 {
 586 }
 587
 588 static inline int iommu_fwspec_init(struct device *dev,
 589                                     struct fwnode_handle *iommu_fwnode,
 590                                     const struct iommu_ops *ops)
 591 {
 592         return -ENODEV;
 593 }
 594
 595 static inline void iommu_fwspec_free(struct device *dev)
 596 {
 597 }
 598
 599 static inline int iommu_fwspec_add_ids(struct device *dev, u32 *ids,
 600                                        int num_ids)
 601 {
 602         return -ENODEV;
 603 }
 604
 605 static inline void iommu_register_instance(struct fwnode_handle *fwnode,
 606                                            const struct iommu_ops *ops)
 607 {
 608 }
 609
 610 static inline
 611 const struct iommu_ops *iommu_get_instance(struct fwnode_handle *fwnode)
 612 {
 613         return NULL;
 614 }
 615
 616 #endif /* CONFIG_IOMMU_API */
 617
 618 #endif /* __LINUX_IOMMU_H */