xref: /linux-6.15/include/linux/iommu.h (revision 3c8d7ef8)
1 /*
2  * Copyright (C) 2007-2008 Advanced Micro Devices, Inc.
3  * Author: Joerg Roedel <[email protected]>
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/scatterlist.h>
23 #include <linux/device.h>
24 #include <linux/types.h>
25 #include <linux/errno.h>
26 #include <linux/err.h>
27 #include <linux/of.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  * Where the bus hardware includes a privilege level as part of its access type
36  * markings, and certain devices are capable of issuing transactions marked as
37  * either 'supervisor' or 'user', the IOMMU_PRIV flag requests that the other
38  * given permission flags only apply to accesses at the higher privilege level,
39  * and that unprivileged transactions should have as little access as possible.
40  * This would usually imply the same permissions as kernel mappings on the CPU,
41  * if the IOMMU page table format is equivalent.
42  */
43 #define IOMMU_PRIV	(1 << 5)
44 
45 struct iommu_ops;
46 struct iommu_group;
47 struct bus_type;
48 struct device;
49 struct iommu_domain;
50 struct notifier_block;
51 
52 /* iommu fault flags */
53 #define IOMMU_FAULT_READ	0x0
54 #define IOMMU_FAULT_WRITE	0x1
55 
56 typedef int (*iommu_fault_handler_t)(struct iommu_domain *,
57 			struct device *, unsigned long, int, void *);
58 
59 struct iommu_domain_geometry {
60 	dma_addr_t aperture_start; /* First address that can be mapped    */
61 	dma_addr_t aperture_end;   /* Last address that can be mapped     */
62 	bool force_aperture;       /* DMA only allowed in mappable range? */
63 };
64 
65 /* Domain feature flags */
66 #define __IOMMU_DOMAIN_PAGING	(1U << 0)  /* Support for iommu_map/unmap */
67 #define __IOMMU_DOMAIN_DMA_API	(1U << 1)  /* Domain for use in DMA-API
68 					      implementation              */
69 #define __IOMMU_DOMAIN_PT	(1U << 2)  /* Domain is identity mapped   */
70 
71 /*
72  * This are the possible domain-types
73  *
74  *	IOMMU_DOMAIN_BLOCKED	- All DMA is blocked, can be used to isolate
75  *				  devices
76  *	IOMMU_DOMAIN_IDENTITY	- DMA addresses are system physical addresses
77  *	IOMMU_DOMAIN_UNMANAGED	- DMA mappings managed by IOMMU-API user, used
78  *				  for VMs
79  *	IOMMU_DOMAIN_DMA	- Internally used for DMA-API implementations.
80  *				  This flag allows IOMMU drivers to implement
81  *				  certain optimizations for these domains
82  */
83 #define IOMMU_DOMAIN_BLOCKED	(0U)
84 #define IOMMU_DOMAIN_IDENTITY	(__IOMMU_DOMAIN_PT)
85 #define IOMMU_DOMAIN_UNMANAGED	(__IOMMU_DOMAIN_PAGING)
86 #define IOMMU_DOMAIN_DMA	(__IOMMU_DOMAIN_PAGING |	\
87 				 __IOMMU_DOMAIN_DMA_API)
88 
89 struct iommu_domain {
90 	unsigned type;
91 	const struct iommu_ops *ops;
92 	unsigned long pgsize_bitmap;	/* Bitmap of page sizes in use */
93 	iommu_fault_handler_t handler;
94 	void *handler_token;
95 	struct iommu_domain_geometry geometry;
96 	void *iova_cookie;
97 };
98 
99 enum iommu_cap {
100 	IOMMU_CAP_CACHE_COHERENCY,	/* IOMMU can enforce cache coherent DMA
101 					   transactions */
102 	IOMMU_CAP_INTR_REMAP,		/* IOMMU supports interrupt isolation */
103 	IOMMU_CAP_NOEXEC,		/* IOMMU_NOEXEC flag */
104 };
105 
106 /*
107  * Following constraints are specifc to FSL_PAMUV1:
108  *  -aperture must be power of 2, and naturally aligned
109  *  -number of windows must be power of 2, and address space size
110  *   of each window is determined by aperture size / # of windows
111  *  -the actual size of the mapped region of a window must be power
112  *   of 2 starting with 4KB and physical address must be naturally
113  *   aligned.
114  * DOMAIN_ATTR_FSL_PAMUV1 corresponds to the above mentioned contraints.
115  * The caller can invoke iommu_domain_get_attr to check if the underlying
116  * iommu implementation supports these constraints.
117  */
118 
119 enum iommu_attr {
120 	DOMAIN_ATTR_GEOMETRY,
121 	DOMAIN_ATTR_PAGING,
122 	DOMAIN_ATTR_WINDOWS,
123 	DOMAIN_ATTR_FSL_PAMU_STASH,
124 	DOMAIN_ATTR_FSL_PAMU_ENABLE,
125 	DOMAIN_ATTR_FSL_PAMUV1,
126 	DOMAIN_ATTR_NESTING,	/* two stages of translation */
127 	DOMAIN_ATTR_DMA_USE_FLUSH_QUEUE,
128 	DOMAIN_ATTR_MAX,
129 };
130 
131 /* These are the possible reserved region types */
132 enum iommu_resv_type {
133 	/* Memory regions which must be mapped 1:1 at all times */
134 	IOMMU_RESV_DIRECT,
135 	/* Arbitrary "never map this or give it to a device" address ranges */
136 	IOMMU_RESV_RESERVED,
137 	/* Hardware MSI region (untranslated) */
138 	IOMMU_RESV_MSI,
139 	/* Software-managed MSI translation window */
140 	IOMMU_RESV_SW_MSI,
141 };
142 
143 /**
144  * struct iommu_resv_region - descriptor for a reserved memory region
145  * @list: Linked list pointers
146  * @start: System physical start address of the region
147  * @length: Length of the region in bytes
148  * @prot: IOMMU Protection flags (READ/WRITE/...)
149  * @type: Type of the reserved region
150  */
151 struct iommu_resv_region {
152 	struct list_head	list;
153 	phys_addr_t		start;
154 	size_t			length;
155 	int			prot;
156 	enum iommu_resv_type	type;
157 };
158 
159 #ifdef CONFIG_IOMMU_API
160 
161 /**
162  * struct iommu_ops - iommu ops and capabilities
163  * @capable: check capability
164  * @domain_alloc: allocate iommu domain
165  * @domain_free: free iommu domain
166  * @attach_dev: attach device to an iommu domain
167  * @detach_dev: detach device from an iommu domain
168  * @map: map a physically contiguous memory region to an iommu domain
169  * @unmap: unmap a physically contiguous memory region from an iommu domain
170  * @flush_tlb_all: Synchronously flush all hardware TLBs for this domain
171  * @iotlb_range_add: Add a given iova range to the flush queue for this domain
172  * @iotlb_sync: Flush all queued ranges from the hardware TLBs and empty flush
173  *            queue
174  * @iova_to_phys: translate iova to physical address
175  * @add_device: add device to iommu grouping
176  * @remove_device: remove device from iommu grouping
177  * @device_group: find iommu group for a particular device
178  * @domain_get_attr: Query domain attributes
179  * @domain_set_attr: Change domain attributes
180  * @get_resv_regions: Request list of reserved regions for a device
181  * @put_resv_regions: Free list of reserved regions for a device
182  * @apply_resv_region: Temporary helper call-back for iova reserved ranges
183  * @domain_window_enable: Configure and enable a particular window for a domain
184  * @domain_window_disable: Disable a particular window for a domain
185  * @of_xlate: add OF master IDs to iommu grouping
186  * @pgsize_bitmap: bitmap of all possible supported page sizes
187  */
188 struct iommu_ops {
189 	bool (*capable)(enum iommu_cap);
190 
191 	/* Domain allocation and freeing by the iommu driver */
192 	struct iommu_domain *(*domain_alloc)(unsigned iommu_domain_type);
193 	void (*domain_free)(struct iommu_domain *);
194 
195 	int (*attach_dev)(struct iommu_domain *domain, struct device *dev);
196 	void (*detach_dev)(struct iommu_domain *domain, struct device *dev);
197 	int (*map)(struct iommu_domain *domain, unsigned long iova,
198 		   phys_addr_t paddr, size_t size, int prot);
199 	size_t (*unmap)(struct iommu_domain *domain, unsigned long iova,
200 		     size_t size);
201 	void (*flush_iotlb_all)(struct iommu_domain *domain);
202 	void (*iotlb_range_add)(struct iommu_domain *domain,
203 				unsigned long iova, size_t size);
204 	void (*iotlb_sync)(struct iommu_domain *domain);
205 	phys_addr_t (*iova_to_phys)(struct iommu_domain *domain, dma_addr_t iova);
206 	int (*add_device)(struct device *dev);
207 	void (*remove_device)(struct device *dev);
208 	struct iommu_group *(*device_group)(struct device *dev);
209 	int (*domain_get_attr)(struct iommu_domain *domain,
210 			       enum iommu_attr attr, void *data);
211 	int (*domain_set_attr)(struct iommu_domain *domain,
212 			       enum iommu_attr attr, void *data);
213 
214 	/* Request/Free a list of reserved regions for a device */
215 	void (*get_resv_regions)(struct device *dev, struct list_head *list);
216 	void (*put_resv_regions)(struct device *dev, struct list_head *list);
217 	void (*apply_resv_region)(struct device *dev,
218 				  struct iommu_domain *domain,
219 				  struct iommu_resv_region *region);
220 
221 	/* Window handling functions */
222 	int (*domain_window_enable)(struct iommu_domain *domain, u32 wnd_nr,
223 				    phys_addr_t paddr, u64 size, int prot);
224 	void (*domain_window_disable)(struct iommu_domain *domain, u32 wnd_nr);
225 
226 	int (*of_xlate)(struct device *dev, struct of_phandle_args *args);
227 	bool (*is_attach_deferred)(struct iommu_domain *domain, struct device *dev);
228 
229 	unsigned long pgsize_bitmap;
230 };
231 
232 /**
233  * struct iommu_device - IOMMU core representation of one IOMMU hardware
234  *			 instance
235  * @list: Used by the iommu-core to keep a list of registered iommus
236  * @ops: iommu-ops for talking to this iommu
237  * @dev: struct device for sysfs handling
238  */
239 struct iommu_device {
240 	struct list_head list;
241 	const struct iommu_ops *ops;
242 	struct fwnode_handle *fwnode;
243 	struct device *dev;
244 };
245 
246 int  iommu_device_register(struct iommu_device *iommu);
247 void iommu_device_unregister(struct iommu_device *iommu);
248 int  iommu_device_sysfs_add(struct iommu_device *iommu,
249 			    struct device *parent,
250 			    const struct attribute_group **groups,
251 			    const char *fmt, ...) __printf(4, 5);
252 void iommu_device_sysfs_remove(struct iommu_device *iommu);
253 int  iommu_device_link(struct iommu_device   *iommu, struct device *link);
254 void iommu_device_unlink(struct iommu_device *iommu, struct device *link);
255 
256 static inline void iommu_device_set_ops(struct iommu_device *iommu,
257 					const struct iommu_ops *ops)
258 {
259 	iommu->ops = ops;
260 }
261 
262 static inline void iommu_device_set_fwnode(struct iommu_device *iommu,
263 					   struct fwnode_handle *fwnode)
264 {
265 	iommu->fwnode = fwnode;
266 }
267 
268 static inline struct iommu_device *dev_to_iommu_device(struct device *dev)
269 {
270 	return (struct iommu_device *)dev_get_drvdata(dev);
271 }
272 
273 #define IOMMU_GROUP_NOTIFY_ADD_DEVICE		1 /* Device added */
274 #define IOMMU_GROUP_NOTIFY_DEL_DEVICE		2 /* Pre Device removed */
275 #define IOMMU_GROUP_NOTIFY_BIND_DRIVER		3 /* Pre Driver bind */
276 #define IOMMU_GROUP_NOTIFY_BOUND_DRIVER		4 /* Post Driver bind */
277 #define IOMMU_GROUP_NOTIFY_UNBIND_DRIVER	5 /* Pre Driver unbind */
278 #define IOMMU_GROUP_NOTIFY_UNBOUND_DRIVER	6 /* Post Driver unbind */
279 
280 extern int bus_set_iommu(struct bus_type *bus, const struct iommu_ops *ops);
281 extern bool iommu_present(struct bus_type *bus);
282 extern bool iommu_capable(struct bus_type *bus, enum iommu_cap cap);
283 extern struct iommu_domain *iommu_domain_alloc(struct bus_type *bus);
284 extern struct iommu_group *iommu_group_get_by_id(int id);
285 extern void iommu_domain_free(struct iommu_domain *domain);
286 extern int iommu_attach_device(struct iommu_domain *domain,
287 			       struct device *dev);
288 extern void iommu_detach_device(struct iommu_domain *domain,
289 				struct device *dev);
290 extern struct iommu_domain *iommu_get_domain_for_dev(struct device *dev);
291 extern struct iommu_domain *iommu_get_dma_domain(struct device *dev);
292 extern int iommu_map(struct iommu_domain *domain, unsigned long iova,
293 		     phys_addr_t paddr, size_t size, int prot);
294 extern size_t iommu_unmap(struct iommu_domain *domain, unsigned long iova,
295 			  size_t size);
296 extern size_t iommu_unmap_fast(struct iommu_domain *domain,
297 			       unsigned long iova, size_t size);
298 extern size_t iommu_map_sg(struct iommu_domain *domain, unsigned long iova,
299 			   struct scatterlist *sg,unsigned int nents, int prot);
300 extern phys_addr_t iommu_iova_to_phys(struct iommu_domain *domain, dma_addr_t iova);
301 extern void iommu_set_fault_handler(struct iommu_domain *domain,
302 			iommu_fault_handler_t handler, void *token);
303 
304 extern void iommu_get_resv_regions(struct device *dev, struct list_head *list);
305 extern void iommu_put_resv_regions(struct device *dev, struct list_head *list);
306 extern int iommu_request_dm_for_dev(struct device *dev);
307 extern struct iommu_resv_region *
308 iommu_alloc_resv_region(phys_addr_t start, size_t length, int prot,
309 			enum iommu_resv_type type);
310 extern int iommu_get_group_resv_regions(struct iommu_group *group,
311 					struct list_head *head);
312 
313 extern int iommu_attach_group(struct iommu_domain *domain,
314 			      struct iommu_group *group);
315 extern void iommu_detach_group(struct iommu_domain *domain,
316 			       struct iommu_group *group);
317 extern struct iommu_group *iommu_group_alloc(void);
318 extern void *iommu_group_get_iommudata(struct iommu_group *group);
319 extern void iommu_group_set_iommudata(struct iommu_group *group,
320 				      void *iommu_data,
321 				      void (*release)(void *iommu_data));
322 extern int iommu_group_set_name(struct iommu_group *group, const char *name);
323 extern int iommu_group_add_device(struct iommu_group *group,
324 				  struct device *dev);
325 extern void iommu_group_remove_device(struct device *dev);
326 extern int iommu_group_for_each_dev(struct iommu_group *group, void *data,
327 				    int (*fn)(struct device *, void *));
328 extern struct iommu_group *iommu_group_get(struct device *dev);
329 extern struct iommu_group *iommu_group_ref_get(struct iommu_group *group);
330 extern void iommu_group_put(struct iommu_group *group);
331 extern int iommu_group_register_notifier(struct iommu_group *group,
332 					 struct notifier_block *nb);
333 extern int iommu_group_unregister_notifier(struct iommu_group *group,
334 					   struct notifier_block *nb);
335 extern int iommu_group_id(struct iommu_group *group);
336 extern struct iommu_group *iommu_group_get_for_dev(struct device *dev);
337 extern struct iommu_domain *iommu_group_default_domain(struct iommu_group *);
338 
339 extern int iommu_domain_get_attr(struct iommu_domain *domain, enum iommu_attr,
340 				 void *data);
341 extern int iommu_domain_set_attr(struct iommu_domain *domain, enum iommu_attr,
342 				 void *data);
343 
344 /* Window handling function prototypes */
345 extern int iommu_domain_window_enable(struct iommu_domain *domain, u32 wnd_nr,
346 				      phys_addr_t offset, u64 size,
347 				      int prot);
348 extern void iommu_domain_window_disable(struct iommu_domain *domain, u32 wnd_nr);
349 
350 extern int report_iommu_fault(struct iommu_domain *domain, struct device *dev,
351 			      unsigned long iova, int flags);
352 
353 static inline void iommu_flush_tlb_all(struct iommu_domain *domain)
354 {
355 	if (domain->ops->flush_iotlb_all)
356 		domain->ops->flush_iotlb_all(domain);
357 }
358 
359 static inline void iommu_tlb_range_add(struct iommu_domain *domain,
360 				       unsigned long iova, size_t size)
361 {
362 	if (domain->ops->iotlb_range_add)
363 		domain->ops->iotlb_range_add(domain, iova, size);
364 }
365 
366 static inline void iommu_tlb_sync(struct iommu_domain *domain)
367 {
368 	if (domain->ops->iotlb_sync)
369 		domain->ops->iotlb_sync(domain);
370 }
371 
372 /* PCI device grouping function */
373 extern struct iommu_group *pci_device_group(struct device *dev);
374 /* Generic device grouping function */
375 extern struct iommu_group *generic_device_group(struct device *dev);
376 /* FSL-MC device grouping function */
377 struct iommu_group *fsl_mc_device_group(struct device *dev);
378 
379 /**
380  * struct iommu_fwspec - per-device IOMMU instance data
381  * @ops: ops for this device's IOMMU
382  * @iommu_fwnode: firmware handle for this device's IOMMU
383  * @iommu_priv: IOMMU driver private data for this device
384  * @num_ids: number of associated device IDs
385  * @ids: IDs which this device may present to the IOMMU
386  */
387 struct iommu_fwspec {
388 	const struct iommu_ops	*ops;
389 	struct fwnode_handle	*iommu_fwnode;
390 	void			*iommu_priv;
391 	unsigned int		num_ids;
392 	u32			ids[1];
393 };
394 
395 int iommu_fwspec_init(struct device *dev, struct fwnode_handle *iommu_fwnode,
396 		      const struct iommu_ops *ops);
397 void iommu_fwspec_free(struct device *dev);
398 int iommu_fwspec_add_ids(struct device *dev, u32 *ids, int num_ids);
399 const struct iommu_ops *iommu_ops_from_fwnode(struct fwnode_handle *fwnode);
400 
401 static inline struct iommu_fwspec *dev_iommu_fwspec_get(struct device *dev)
402 {
403 	return dev->iommu_fwspec;
404 }
405 
406 static inline void dev_iommu_fwspec_set(struct device *dev,
407 					struct iommu_fwspec *fwspec)
408 {
409 	dev->iommu_fwspec = fwspec;
410 }
411 
412 int iommu_probe_device(struct device *dev);
413 void iommu_release_device(struct device *dev);
414 
415 #else /* CONFIG_IOMMU_API */
416 
417 struct iommu_ops {};
418 struct iommu_group {};
419 struct iommu_fwspec {};
420 struct iommu_device {};
421 
422 static inline bool iommu_present(struct bus_type *bus)
423 {
424 	return false;
425 }
426 
427 static inline bool iommu_capable(struct bus_type *bus, enum iommu_cap cap)
428 {
429 	return false;
430 }
431 
432 static inline struct iommu_domain *iommu_domain_alloc(struct bus_type *bus)
433 {
434 	return NULL;
435 }
436 
437 static inline struct iommu_group *iommu_group_get_by_id(int id)
438 {
439 	return NULL;
440 }
441 
442 static inline void iommu_domain_free(struct iommu_domain *domain)
443 {
444 }
445 
446 static inline int iommu_attach_device(struct iommu_domain *domain,
447 				      struct device *dev)
448 {
449 	return -ENODEV;
450 }
451 
452 static inline void iommu_detach_device(struct iommu_domain *domain,
453 				       struct device *dev)
454 {
455 }
456 
457 static inline struct iommu_domain *iommu_get_domain_for_dev(struct device *dev)
458 {
459 	return NULL;
460 }
461 
462 static inline int iommu_map(struct iommu_domain *domain, unsigned long iova,
463 			    phys_addr_t paddr, size_t size, int prot)
464 {
465 	return -ENODEV;
466 }
467 
468 static inline size_t iommu_unmap(struct iommu_domain *domain,
469 				 unsigned long iova, size_t size)
470 {
471 	return 0;
472 }
473 
474 static inline size_t iommu_unmap_fast(struct iommu_domain *domain,
475 				      unsigned long iova, int gfp_order)
476 {
477 	return 0;
478 }
479 
480 static inline size_t iommu_map_sg(struct iommu_domain *domain,
481 				  unsigned long iova, struct scatterlist *sg,
482 				  unsigned int nents, int prot)
483 {
484 	return 0;
485 }
486 
487 static inline void iommu_flush_tlb_all(struct iommu_domain *domain)
488 {
489 }
490 
491 static inline void iommu_tlb_range_add(struct iommu_domain *domain,
492 				       unsigned long iova, size_t size)
493 {
494 }
495 
496 static inline void iommu_tlb_sync(struct iommu_domain *domain)
497 {
498 }
499 
500 static inline int iommu_domain_window_enable(struct iommu_domain *domain,
501 					     u32 wnd_nr, phys_addr_t paddr,
502 					     u64 size, int prot)
503 {
504 	return -ENODEV;
505 }
506 
507 static inline void iommu_domain_window_disable(struct iommu_domain *domain,
508 					       u32 wnd_nr)
509 {
510 }
511 
512 static inline phys_addr_t iommu_iova_to_phys(struct iommu_domain *domain, dma_addr_t iova)
513 {
514 	return 0;
515 }
516 
517 static inline void iommu_set_fault_handler(struct iommu_domain *domain,
518 				iommu_fault_handler_t handler, void *token)
519 {
520 }
521 
522 static inline void iommu_get_resv_regions(struct device *dev,
523 					struct list_head *list)
524 {
525 }
526 
527 static inline void iommu_put_resv_regions(struct device *dev,
528 					struct list_head *list)
529 {
530 }
531 
532 static inline int iommu_get_group_resv_regions(struct iommu_group *group,
533 					       struct list_head *head)
534 {
535 	return -ENODEV;
536 }
537 
538 static inline int iommu_request_dm_for_dev(struct device *dev)
539 {
540 	return -ENODEV;
541 }
542 
543 static inline int iommu_attach_group(struct iommu_domain *domain,
544 				     struct iommu_group *group)
545 {
546 	return -ENODEV;
547 }
548 
549 static inline void iommu_detach_group(struct iommu_domain *domain,
550 				      struct iommu_group *group)
551 {
552 }
553 
554 static inline struct iommu_group *iommu_group_alloc(void)
555 {
556 	return ERR_PTR(-ENODEV);
557 }
558 
559 static inline void *iommu_group_get_iommudata(struct iommu_group *group)
560 {
561 	return NULL;
562 }
563 
564 static inline void iommu_group_set_iommudata(struct iommu_group *group,
565 					     void *iommu_data,
566 					     void (*release)(void *iommu_data))
567 {
568 }
569 
570 static inline int iommu_group_set_name(struct iommu_group *group,
571 				       const char *name)
572 {
573 	return -ENODEV;
574 }
575 
576 static inline int iommu_group_add_device(struct iommu_group *group,
577 					 struct device *dev)
578 {
579 	return -ENODEV;
580 }
581 
582 static inline void iommu_group_remove_device(struct device *dev)
583 {
584 }
585 
586 static inline int iommu_group_for_each_dev(struct iommu_group *group,
587 					   void *data,
588 					   int (*fn)(struct device *, void *))
589 {
590 	return -ENODEV;
591 }
592 
593 static inline struct iommu_group *iommu_group_get(struct device *dev)
594 {
595 	return NULL;
596 }
597 
598 static inline void iommu_group_put(struct iommu_group *group)
599 {
600 }
601 
602 static inline int iommu_group_register_notifier(struct iommu_group *group,
603 						struct notifier_block *nb)
604 {
605 	return -ENODEV;
606 }
607 
608 static inline int iommu_group_unregister_notifier(struct iommu_group *group,
609 						  struct notifier_block *nb)
610 {
611 	return 0;
612 }
613 
614 static inline int iommu_group_id(struct iommu_group *group)
615 {
616 	return -ENODEV;
617 }
618 
619 static inline int iommu_domain_get_attr(struct iommu_domain *domain,
620 					enum iommu_attr attr, void *data)
621 {
622 	return -EINVAL;
623 }
624 
625 static inline int iommu_domain_set_attr(struct iommu_domain *domain,
626 					enum iommu_attr attr, void *data)
627 {
628 	return -EINVAL;
629 }
630 
631 static inline int  iommu_device_register(struct iommu_device *iommu)
632 {
633 	return -ENODEV;
634 }
635 
636 static inline void iommu_device_set_ops(struct iommu_device *iommu,
637 					const struct iommu_ops *ops)
638 {
639 }
640 
641 static inline void iommu_device_set_fwnode(struct iommu_device *iommu,
642 					   struct fwnode_handle *fwnode)
643 {
644 }
645 
646 static inline struct iommu_device *dev_to_iommu_device(struct device *dev)
647 {
648 	return NULL;
649 }
650 
651 static inline void iommu_device_unregister(struct iommu_device *iommu)
652 {
653 }
654 
655 static inline int  iommu_device_sysfs_add(struct iommu_device *iommu,
656 					  struct device *parent,
657 					  const struct attribute_group **groups,
658 					  const char *fmt, ...)
659 {
660 	return -ENODEV;
661 }
662 
663 static inline void iommu_device_sysfs_remove(struct iommu_device *iommu)
664 {
665 }
666 
667 static inline int iommu_device_link(struct device *dev, struct device *link)
668 {
669 	return -EINVAL;
670 }
671 
672 static inline void iommu_device_unlink(struct device *dev, struct device *link)
673 {
674 }
675 
676 static inline int iommu_fwspec_init(struct device *dev,
677 				    struct fwnode_handle *iommu_fwnode,
678 				    const struct iommu_ops *ops)
679 {
680 	return -ENODEV;
681 }
682 
683 static inline void iommu_fwspec_free(struct device *dev)
684 {
685 }
686 
687 static inline int iommu_fwspec_add_ids(struct device *dev, u32 *ids,
688 				       int num_ids)
689 {
690 	return -ENODEV;
691 }
692 
693 static inline
694 const struct iommu_ops *iommu_ops_from_fwnode(struct fwnode_handle *fwnode)
695 {
696 	return NULL;
697 }
698 
699 #endif /* CONFIG_IOMMU_API */
700 
701 #ifdef CONFIG_IOMMU_DEBUGFS
702 extern	struct dentry *iommu_debugfs_dir;
703 void iommu_debugfs_setup(void);
704 #else
705 static inline void iommu_debugfs_setup(void) {}
706 #endif
707 
708 #endif /* __LINUX_IOMMU_H */
709