xref: /linux-6.15/include/linux/iommu.h (revision b9ccfda2)
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/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 iommu_group;
30 struct bus_type;
31 struct device;
32 struct iommu_domain;
33 
34 /* iommu fault flags */
35 #define IOMMU_FAULT_READ	0x0
36 #define IOMMU_FAULT_WRITE	0x1
37 
38 typedef int (*iommu_fault_handler_t)(struct iommu_domain *,
39 			struct device *, unsigned long, int, void *);
40 
41 struct iommu_domain_geometry {
42 	dma_addr_t aperture_start; /* First address that can be mapped    */
43 	dma_addr_t aperture_end;   /* Last address that can be mapped     */
44 	bool force_aperture;       /* DMA only allowed in mappable range? */
45 };
46 
47 struct iommu_domain {
48 	struct iommu_ops *ops;
49 	void *priv;
50 	iommu_fault_handler_t handler;
51 	void *handler_token;
52 	struct iommu_domain_geometry geometry;
53 };
54 
55 #define IOMMU_CAP_CACHE_COHERENCY	0x1
56 #define IOMMU_CAP_INTR_REMAP		0x2	/* isolates device intrs */
57 
58 enum iommu_attr {
59 	DOMAIN_ATTR_MAX,
60 	DOMAIN_ATTR_GEOMETRY,
61 };
62 
63 #ifdef CONFIG_IOMMU_API
64 
65 /**
66  * struct iommu_ops - iommu ops and capabilities
67  * @domain_init: init iommu domain
68  * @domain_destroy: destroy iommu domain
69  * @attach_dev: attach device to an iommu domain
70  * @detach_dev: detach device from an iommu domain
71  * @map: map a physically contiguous memory region to an iommu domain
72  * @unmap: unmap a physically contiguous memory region from an iommu domain
73  * @iova_to_phys: translate iova to physical address
74  * @domain_has_cap: domain capabilities query
75  * @add_device: add device to iommu grouping
76  * @remove_device: remove device from iommu grouping
77  * @domain_get_attr: Query domain attributes
78  * @domain_set_attr: Change domain attributes
79  * @pgsize_bitmap: bitmap of supported page sizes
80  */
81 struct iommu_ops {
82 	int (*domain_init)(struct iommu_domain *domain);
83 	void (*domain_destroy)(struct iommu_domain *domain);
84 	int (*attach_dev)(struct iommu_domain *domain, struct device *dev);
85 	void (*detach_dev)(struct iommu_domain *domain, struct device *dev);
86 	int (*map)(struct iommu_domain *domain, unsigned long iova,
87 		   phys_addr_t paddr, size_t size, int prot);
88 	size_t (*unmap)(struct iommu_domain *domain, unsigned long iova,
89 		     size_t size);
90 	phys_addr_t (*iova_to_phys)(struct iommu_domain *domain,
91 				    unsigned long iova);
92 	int (*domain_has_cap)(struct iommu_domain *domain,
93 			      unsigned long cap);
94 	int (*add_device)(struct device *dev);
95 	void (*remove_device)(struct device *dev);
96 	int (*device_group)(struct device *dev, unsigned int *groupid);
97 	int (*domain_get_attr)(struct iommu_domain *domain,
98 			       enum iommu_attr attr, void *data);
99 	int (*domain_set_attr)(struct iommu_domain *domain,
100 			       enum iommu_attr attr, void *data);
101 	unsigned long pgsize_bitmap;
102 };
103 
104 #define IOMMU_GROUP_NOTIFY_ADD_DEVICE		1 /* Device added */
105 #define IOMMU_GROUP_NOTIFY_DEL_DEVICE		2 /* Pre Device removed */
106 #define IOMMU_GROUP_NOTIFY_BIND_DRIVER		3 /* Pre Driver bind */
107 #define IOMMU_GROUP_NOTIFY_BOUND_DRIVER		4 /* Post Driver bind */
108 #define IOMMU_GROUP_NOTIFY_UNBIND_DRIVER	5 /* Pre Driver unbind */
109 #define IOMMU_GROUP_NOTIFY_UNBOUND_DRIVER	6 /* Post Driver unbind */
110 
111 extern int bus_set_iommu(struct bus_type *bus, struct iommu_ops *ops);
112 extern bool iommu_present(struct bus_type *bus);
113 extern struct iommu_domain *iommu_domain_alloc(struct bus_type *bus);
114 extern void iommu_domain_free(struct iommu_domain *domain);
115 extern int iommu_attach_device(struct iommu_domain *domain,
116 			       struct device *dev);
117 extern void iommu_detach_device(struct iommu_domain *domain,
118 				struct device *dev);
119 extern int iommu_map(struct iommu_domain *domain, unsigned long iova,
120 		     phys_addr_t paddr, size_t size, int prot);
121 extern size_t iommu_unmap(struct iommu_domain *domain, unsigned long iova,
122 		       size_t size);
123 extern phys_addr_t iommu_iova_to_phys(struct iommu_domain *domain,
124 				      unsigned long iova);
125 extern int iommu_domain_has_cap(struct iommu_domain *domain,
126 				unsigned long cap);
127 extern void iommu_set_fault_handler(struct iommu_domain *domain,
128 			iommu_fault_handler_t handler, void *token);
129 
130 extern int iommu_attach_group(struct iommu_domain *domain,
131 			      struct iommu_group *group);
132 extern void iommu_detach_group(struct iommu_domain *domain,
133 			       struct iommu_group *group);
134 extern struct iommu_group *iommu_group_alloc(void);
135 extern void *iommu_group_get_iommudata(struct iommu_group *group);
136 extern void iommu_group_set_iommudata(struct iommu_group *group,
137 				      void *iommu_data,
138 				      void (*release)(void *iommu_data));
139 extern int iommu_group_set_name(struct iommu_group *group, const char *name);
140 extern int iommu_group_add_device(struct iommu_group *group,
141 				  struct device *dev);
142 extern void iommu_group_remove_device(struct device *dev);
143 extern int iommu_group_for_each_dev(struct iommu_group *group, void *data,
144 				    int (*fn)(struct device *, void *));
145 extern struct iommu_group *iommu_group_get(struct device *dev);
146 extern void iommu_group_put(struct iommu_group *group);
147 extern int iommu_group_register_notifier(struct iommu_group *group,
148 					 struct notifier_block *nb);
149 extern int iommu_group_unregister_notifier(struct iommu_group *group,
150 					   struct notifier_block *nb);
151 extern int iommu_group_id(struct iommu_group *group);
152 
153 extern int iommu_domain_get_attr(struct iommu_domain *domain, enum iommu_attr,
154 				 void *data);
155 extern int iommu_domain_set_attr(struct iommu_domain *domain, enum iommu_attr,
156 				 void *data);
157 
158 /**
159  * report_iommu_fault() - report about an IOMMU fault to the IOMMU framework
160  * @domain: the iommu domain where the fault has happened
161  * @dev: the device where the fault has happened
162  * @iova: the faulting address
163  * @flags: mmu fault flags (e.g. IOMMU_FAULT_READ/IOMMU_FAULT_WRITE/...)
164  *
165  * This function should be called by the low-level IOMMU implementations
166  * whenever IOMMU faults happen, to allow high-level users, that are
167  * interested in such events, to know about them.
168  *
169  * This event may be useful for several possible use cases:
170  * - mere logging of the event
171  * - dynamic TLB/PTE loading
172  * - if restarting of the faulting device is required
173  *
174  * Returns 0 on success and an appropriate error code otherwise (if dynamic
175  * PTE/TLB loading will one day be supported, implementations will be able
176  * to tell whether it succeeded or not according to this return value).
177  *
178  * Specifically, -ENOSYS is returned if a fault handler isn't installed
179  * (though fault handlers can also return -ENOSYS, in case they want to
180  * elicit the default behavior of the IOMMU drivers).
181  */
182 static inline int report_iommu_fault(struct iommu_domain *domain,
183 		struct device *dev, unsigned long iova, int flags)
184 {
185 	int ret = -ENOSYS;
186 
187 	/*
188 	 * if upper layers showed interest and installed a fault handler,
189 	 * invoke it.
190 	 */
191 	if (domain->handler)
192 		ret = domain->handler(domain, dev, iova, flags,
193 						domain->handler_token);
194 
195 	return ret;
196 }
197 
198 #else /* CONFIG_IOMMU_API */
199 
200 struct iommu_ops {};
201 struct iommu_group {};
202 
203 static inline bool iommu_present(struct bus_type *bus)
204 {
205 	return false;
206 }
207 
208 static inline struct iommu_domain *iommu_domain_alloc(struct bus_type *bus)
209 {
210 	return NULL;
211 }
212 
213 static inline void iommu_domain_free(struct iommu_domain *domain)
214 {
215 }
216 
217 static inline int iommu_attach_device(struct iommu_domain *domain,
218 				      struct device *dev)
219 {
220 	return -ENODEV;
221 }
222 
223 static inline void iommu_detach_device(struct iommu_domain *domain,
224 				       struct device *dev)
225 {
226 }
227 
228 static inline int iommu_map(struct iommu_domain *domain, unsigned long iova,
229 			    phys_addr_t paddr, int gfp_order, int prot)
230 {
231 	return -ENODEV;
232 }
233 
234 static inline int iommu_unmap(struct iommu_domain *domain, unsigned long iova,
235 			      int gfp_order)
236 {
237 	return -ENODEV;
238 }
239 
240 static inline phys_addr_t iommu_iova_to_phys(struct iommu_domain *domain,
241 					     unsigned long iova)
242 {
243 	return 0;
244 }
245 
246 static inline int domain_has_cap(struct iommu_domain *domain,
247 				 unsigned long cap)
248 {
249 	return 0;
250 }
251 
252 static inline void iommu_set_fault_handler(struct iommu_domain *domain,
253 				iommu_fault_handler_t handler, void *token)
254 {
255 }
256 
257 int iommu_attach_group(struct iommu_domain *domain, struct iommu_group *group)
258 {
259 	return -ENODEV;
260 }
261 
262 void iommu_detach_group(struct iommu_domain *domain, struct iommu_group *group)
263 {
264 }
265 
266 struct iommu_group *iommu_group_alloc(void)
267 {
268 	return ERR_PTR(-ENODEV);
269 }
270 
271 void *iommu_group_get_iommudata(struct iommu_group *group)
272 {
273 	return NULL;
274 }
275 
276 void iommu_group_set_iommudata(struct iommu_group *group, void *iommu_data,
277 			       void (*release)(void *iommu_data))
278 {
279 }
280 
281 int iommu_group_set_name(struct iommu_group *group, const char *name)
282 {
283 	return -ENODEV;
284 }
285 
286 int iommu_group_add_device(struct iommu_group *group, struct device *dev)
287 {
288 	return -ENODEV;
289 }
290 
291 void iommu_group_remove_device(struct device *dev)
292 {
293 }
294 
295 int iommu_group_for_each_dev(struct iommu_group *group, void *data,
296 			     int (*fn)(struct device *, void *))
297 {
298 	return -ENODEV;
299 }
300 
301 struct iommu_group *iommu_group_get(struct device *dev)
302 {
303 	return NULL;
304 }
305 
306 void iommu_group_put(struct iommu_group *group)
307 {
308 }
309 
310 int iommu_group_register_notifier(struct iommu_group *group,
311 				  struct notifier_block *nb)
312 {
313 	return -ENODEV;
314 }
315 
316 int iommu_group_unregister_notifier(struct iommu_group *group,
317 				    struct notifier_block *nb)
318 {
319 	return 0;
320 }
321 
322 int iommu_group_id(struct iommu_group *group)
323 {
324 	return -ENODEV;
325 }
326 
327 static inline int iommu_domain_get_attr(struct iommu_domain *domain,
328 					enum iommu_attr attr, void *data)
329 {
330 	return -EINVAL;
331 }
332 
333 static inline int iommu_domain_set_attr(struct iommu_domain *domain,
334 					enum iommu_attr attr, void *data)
335 {
336 	return -EINVAL;
337 }
338 
339 #endif /* CONFIG_IOMMU_API */
340 
341 #endif /* __LINUX_IOMMU_H */
342