iommu.c (9a64e8e0ace51b309fdcff4b4754b3649250382a) iommu.c (d72e31c9374627068df29da8085ca18c92ae35d3)
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 *

--- 12 unchanged lines hidden (view full) ---

21#include <linux/device.h>
22#include <linux/kernel.h>
23#include <linux/bug.h>
24#include <linux/types.h>
25#include <linux/module.h>
26#include <linux/slab.h>
27#include <linux/errno.h>
28#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 *

--- 12 unchanged lines hidden (view full) ---

21#include <linux/device.h>
22#include <linux/kernel.h>
23#include <linux/bug.h>
24#include <linux/types.h>
25#include <linux/module.h>
26#include <linux/slab.h>
27#include <linux/errno.h>
28#include <linux/iommu.h>
29#include <linux/idr.h>
30#include <linux/notifier.h>
31#include <linux/err.h>
29
32
30static ssize_t show_iommu_group(struct device *dev,
31 struct device_attribute *attr, char *buf)
33static struct kset *iommu_group_kset;
34static struct ida iommu_group_ida;
35static struct mutex iommu_group_mutex;
36
37struct iommu_group {
38 struct kobject kobj;
39 struct kobject *devices_kobj;
40 struct list_head devices;
41 struct mutex mutex;
42 struct blocking_notifier_head notifier;
43 void *iommu_data;
44 void (*iommu_data_release)(void *iommu_data);
45 char *name;
46 int id;
47};
48
49struct iommu_device {
50 struct list_head list;
51 struct device *dev;
52 char *name;
53};
54
55struct iommu_group_attribute {
56 struct attribute attr;
57 ssize_t (*show)(struct iommu_group *group, char *buf);
58 ssize_t (*store)(struct iommu_group *group,
59 const char *buf, size_t count);
60};
61
62#define IOMMU_GROUP_ATTR(_name, _mode, _show, _store) \
63struct iommu_group_attribute iommu_group_attr_##_name = \
64 __ATTR(_name, _mode, _show, _store)
65
66#define to_iommu_group_attr(_attr) \
67 container_of(_attr, struct iommu_group_attribute, attr)
68#define to_iommu_group(_kobj) \
69 container_of(_kobj, struct iommu_group, kobj)
70
71static ssize_t iommu_group_attr_show(struct kobject *kobj,
72 struct attribute *__attr, char *buf)
32{
73{
33 unsigned int groupid;
74 struct iommu_group_attribute *attr = to_iommu_group_attr(__attr);
75 struct iommu_group *group = to_iommu_group(kobj);
76 ssize_t ret = -EIO;
34
77
35 if (iommu_device_group(dev, &groupid))
36 return 0;
78 if (attr->show)
79 ret = attr->show(group, buf);
80 return ret;
81}
37
82
38 return sprintf(buf, "%u", groupid);
83static ssize_t iommu_group_attr_store(struct kobject *kobj,
84 struct attribute *__attr,
85 const char *buf, size_t count)
86{
87 struct iommu_group_attribute *attr = to_iommu_group_attr(__attr);
88 struct iommu_group *group = to_iommu_group(kobj);
89 ssize_t ret = -EIO;
90
91 if (attr->store)
92 ret = attr->store(group, buf, count);
93 return ret;
39}
94}
40static DEVICE_ATTR(iommu_group, S_IRUGO, show_iommu_group, NULL);
41
95
42static int add_iommu_group(struct device *dev, void *data)
96static const struct sysfs_ops iommu_group_sysfs_ops = {
97 .show = iommu_group_attr_show,
98 .store = iommu_group_attr_store,
99};
100
101static int iommu_group_create_file(struct iommu_group *group,
102 struct iommu_group_attribute *attr)
43{
103{
44 unsigned int groupid;
104 return sysfs_create_file(&group->kobj, &attr->attr);
105}
45
106
46 if (iommu_device_group(dev, &groupid) == 0)
47 return device_create_file(dev, &dev_attr_iommu_group);
107static void iommu_group_remove_file(struct iommu_group *group,
108 struct iommu_group_attribute *attr)
109{
110 sysfs_remove_file(&group->kobj, &attr->attr);
111}
48
112
113static ssize_t iommu_group_show_name(struct iommu_group *group, char *buf)
114{
115 return sprintf(buf, "%s\n", group->name);
116}
117
118static IOMMU_GROUP_ATTR(name, S_IRUGO, iommu_group_show_name, NULL);
119
120static void iommu_group_release(struct kobject *kobj)
121{
122 struct iommu_group *group = to_iommu_group(kobj);
123
124 if (group->iommu_data_release)
125 group->iommu_data_release(group->iommu_data);
126
127 mutex_lock(&iommu_group_mutex);
128 ida_remove(&iommu_group_ida, group->id);
129 mutex_unlock(&iommu_group_mutex);
130
131 kfree(group->name);
132 kfree(group);
133}
134
135static struct kobj_type iommu_group_ktype = {
136 .sysfs_ops = &iommu_group_sysfs_ops,
137 .release = iommu_group_release,
138};
139
140/**
141 * iommu_group_alloc - Allocate a new group
142 * @name: Optional name to associate with group, visible in sysfs
143 *
144 * This function is called by an iommu driver to allocate a new iommu
145 * group. The iommu group represents the minimum granularity of the iommu.
146 * Upon successful return, the caller holds a reference to the supplied
147 * group in order to hold the group until devices are added. Use
148 * iommu_group_put() to release this extra reference count, allowing the
149 * group to be automatically reclaimed once it has no devices or external
150 * references.
151 */
152struct iommu_group *iommu_group_alloc(void)
153{
154 struct iommu_group *group;
155 int ret;
156
157 group = kzalloc(sizeof(*group), GFP_KERNEL);
158 if (!group)
159 return ERR_PTR(-ENOMEM);
160
161 group->kobj.kset = iommu_group_kset;
162 mutex_init(&group->mutex);
163 INIT_LIST_HEAD(&group->devices);
164 BLOCKING_INIT_NOTIFIER_HEAD(&group->notifier);
165
166 mutex_lock(&iommu_group_mutex);
167
168again:
169 if (unlikely(0 == ida_pre_get(&iommu_group_ida, GFP_KERNEL))) {
170 kfree(group);
171 mutex_unlock(&iommu_group_mutex);
172 return ERR_PTR(-ENOMEM);
173 }
174
175 if (-EAGAIN == ida_get_new(&iommu_group_ida, &group->id))
176 goto again;
177
178 mutex_unlock(&iommu_group_mutex);
179
180 ret = kobject_init_and_add(&group->kobj, &iommu_group_ktype,
181 NULL, "%d", group->id);
182 if (ret) {
183 mutex_lock(&iommu_group_mutex);
184 ida_remove(&iommu_group_ida, group->id);
185 mutex_unlock(&iommu_group_mutex);
186 kfree(group);
187 return ERR_PTR(ret);
188 }
189
190 group->devices_kobj = kobject_create_and_add("devices", &group->kobj);
191 if (!group->devices_kobj) {
192 kobject_put(&group->kobj); /* triggers .release & free */
193 return ERR_PTR(-ENOMEM);
194 }
195
196 /*
197 * The devices_kobj holds a reference on the group kobject, so
198 * as long as that exists so will the group. We can therefore
199 * use the devices_kobj for reference counting.
200 */
201 kobject_put(&group->kobj);
202
203 return group;
204}
205EXPORT_SYMBOL_GPL(iommu_group_alloc);
206
207/**
208 * iommu_group_get_iommudata - retrieve iommu_data registered for a group
209 * @group: the group
210 *
211 * iommu drivers can store data in the group for use when doing iommu
212 * operations. This function provides a way to retrieve it. Caller
213 * should hold a group reference.
214 */
215void *iommu_group_get_iommudata(struct iommu_group *group)
216{
217 return group->iommu_data;
218}
219EXPORT_SYMBOL_GPL(iommu_group_get_iommudata);
220
221/**
222 * iommu_group_set_iommudata - set iommu_data for a group
223 * @group: the group
224 * @iommu_data: new data
225 * @release: release function for iommu_data
226 *
227 * iommu drivers can store data in the group for use when doing iommu
228 * operations. This function provides a way to set the data after
229 * the group has been allocated. Caller should hold a group reference.
230 */
231void iommu_group_set_iommudata(struct iommu_group *group, void *iommu_data,
232 void (*release)(void *iommu_data))
233{
234 group->iommu_data = iommu_data;
235 group->iommu_data_release = release;
236}
237EXPORT_SYMBOL_GPL(iommu_group_set_iommudata);
238
239/**
240 * iommu_group_set_name - set name for a group
241 * @group: the group
242 * @name: name
243 *
244 * Allow iommu driver to set a name for a group. When set it will
245 * appear in a name attribute file under the group in sysfs.
246 */
247int iommu_group_set_name(struct iommu_group *group, const char *name)
248{
249 int ret;
250
251 if (group->name) {
252 iommu_group_remove_file(group, &iommu_group_attr_name);
253 kfree(group->name);
254 group->name = NULL;
255 if (!name)
256 return 0;
257 }
258
259 group->name = kstrdup(name, GFP_KERNEL);
260 if (!group->name)
261 return -ENOMEM;
262
263 ret = iommu_group_create_file(group, &iommu_group_attr_name);
264 if (ret) {
265 kfree(group->name);
266 group->name = NULL;
267 return ret;
268 }
269
49 return 0;
50}
270 return 0;
271}
272EXPORT_SYMBOL_GPL(iommu_group_set_name);
51
273
52static int remove_iommu_group(struct device *dev)
274/**
275 * iommu_group_add_device - add a device to an iommu group
276 * @group: the group into which to add the device (reference should be held)
277 * @dev: the device
278 *
279 * This function is called by an iommu driver to add a device into a
280 * group. Adding a device increments the group reference count.
281 */
282int iommu_group_add_device(struct iommu_group *group, struct device *dev)
53{
283{
54 unsigned int groupid;
284 int ret, i = 0;
285 struct iommu_device *device;
55
286
56 if (iommu_device_group(dev, &groupid) == 0)
57 device_remove_file(dev, &dev_attr_iommu_group);
287 device = kzalloc(sizeof(*device), GFP_KERNEL);
288 if (!device)
289 return -ENOMEM;
58
290
291 device->dev = dev;
292
293 ret = sysfs_create_link(&dev->kobj, &group->kobj, "iommu_group");
294 if (ret) {
295 kfree(device);
296 return ret;
297 }
298
299 device->name = kasprintf(GFP_KERNEL, "%s", kobject_name(&dev->kobj));
300rename:
301 if (!device->name) {
302 sysfs_remove_link(&dev->kobj, "iommu_group");
303 kfree(device);
304 return -ENOMEM;
305 }
306
307 ret = sysfs_create_link_nowarn(group->devices_kobj,
308 &dev->kobj, device->name);
309 if (ret) {
310 kfree(device->name);
311 if (ret == -EEXIST && i >= 0) {
312 /*
313 * Account for the slim chance of collision
314 * and append an instance to the name.
315 */
316 device->name = kasprintf(GFP_KERNEL, "%s.%d",
317 kobject_name(&dev->kobj), i++);
318 goto rename;
319 }
320
321 sysfs_remove_link(&dev->kobj, "iommu_group");
322 kfree(device);
323 return ret;
324 }
325
326 kobject_get(group->devices_kobj);
327
328 dev->iommu_group = group;
329
330 mutex_lock(&group->mutex);
331 list_add_tail(&device->list, &group->devices);
332 mutex_unlock(&group->mutex);
333
334 /* Notify any listeners about change to group. */
335 blocking_notifier_call_chain(&group->notifier,
336 IOMMU_GROUP_NOTIFY_ADD_DEVICE, dev);
59 return 0;
60}
337 return 0;
338}
339EXPORT_SYMBOL_GPL(iommu_group_add_device);
61
340
62static int iommu_device_notifier(struct notifier_block *nb,
63 unsigned long action, void *data)
341/**
342 * iommu_group_remove_device - remove a device from it's current group
343 * @dev: device to be removed
344 *
345 * This function is called by an iommu driver to remove the device from
346 * it's current group. This decrements the iommu group reference count.
347 */
348void iommu_group_remove_device(struct device *dev)
64{
349{
350 struct iommu_group *group = dev->iommu_group;
351 struct iommu_device *tmp_device, *device = NULL;
352
353 /* Pre-notify listeners that a device is being removed. */
354 blocking_notifier_call_chain(&group->notifier,
355 IOMMU_GROUP_NOTIFY_DEL_DEVICE, dev);
356
357 mutex_lock(&group->mutex);
358 list_for_each_entry(tmp_device, &group->devices, list) {
359 if (tmp_device->dev == dev) {
360 device = tmp_device;
361 list_del(&device->list);
362 break;
363 }
364 }
365 mutex_unlock(&group->mutex);
366
367 if (!device)
368 return;
369
370 sysfs_remove_link(group->devices_kobj, device->name);
371 sysfs_remove_link(&dev->kobj, "iommu_group");
372
373 kfree(device->name);
374 kfree(device);
375 dev->iommu_group = NULL;
376 kobject_put(group->devices_kobj);
377}
378EXPORT_SYMBOL_GPL(iommu_group_remove_device);
379
380/**
381 * iommu_group_for_each_dev - iterate over each device in the group
382 * @group: the group
383 * @data: caller opaque data to be passed to callback function
384 * @fn: caller supplied callback function
385 *
386 * This function is called by group users to iterate over group devices.
387 * Callers should hold a reference count to the group during callback.
388 * The group->mutex is held across callbacks, which will block calls to
389 * iommu_group_add/remove_device.
390 */
391int iommu_group_for_each_dev(struct iommu_group *group, void *data,
392 int (*fn)(struct device *, void *))
393{
394 struct iommu_device *device;
395 int ret = 0;
396
397 mutex_lock(&group->mutex);
398 list_for_each_entry(device, &group->devices, list) {
399 ret = fn(device->dev, data);
400 if (ret)
401 break;
402 }
403 mutex_unlock(&group->mutex);
404 return ret;
405}
406EXPORT_SYMBOL_GPL(iommu_group_for_each_dev);
407
408/**
409 * iommu_group_get - Return the group for a device and increment reference
410 * @dev: get the group that this device belongs to
411 *
412 * This function is called by iommu drivers and users to get the group
413 * for the specified device. If found, the group is returned and the group
414 * reference in incremented, else NULL.
415 */
416struct iommu_group *iommu_group_get(struct device *dev)
417{
418 struct iommu_group *group = dev->iommu_group;
419
420 if (group)
421 kobject_get(group->devices_kobj);
422
423 return group;
424}
425EXPORT_SYMBOL_GPL(iommu_group_get);
426
427/**
428 * iommu_group_put - Decrement group reference
429 * @group: the group to use
430 *
431 * This function is called by iommu drivers and users to release the
432 * iommu group. Once the reference count is zero, the group is released.
433 */
434void iommu_group_put(struct iommu_group *group)
435{
436 if (group)
437 kobject_put(group->devices_kobj);
438}
439EXPORT_SYMBOL_GPL(iommu_group_put);
440
441/**
442 * iommu_group_register_notifier - Register a notifier for group changes
443 * @group: the group to watch
444 * @nb: notifier block to signal
445 *
446 * This function allows iommu group users to track changes in a group.
447 * See include/linux/iommu.h for actions sent via this notifier. Caller
448 * should hold a reference to the group throughout notifier registration.
449 */
450int iommu_group_register_notifier(struct iommu_group *group,
451 struct notifier_block *nb)
452{
453 return blocking_notifier_chain_register(&group->notifier, nb);
454}
455EXPORT_SYMBOL_GPL(iommu_group_register_notifier);
456
457/**
458 * iommu_group_unregister_notifier - Unregister a notifier
459 * @group: the group to watch
460 * @nb: notifier block to signal
461 *
462 * Unregister a previously registered group notifier block.
463 */
464int iommu_group_unregister_notifier(struct iommu_group *group,
465 struct notifier_block *nb)
466{
467 return blocking_notifier_chain_unregister(&group->notifier, nb);
468}
469EXPORT_SYMBOL_GPL(iommu_group_unregister_notifier);
470
471/**
472 * iommu_group_id - Return ID for a group
473 * @group: the group to ID
474 *
475 * Return the unique ID for the group matching the sysfs group number.
476 */
477int iommu_group_id(struct iommu_group *group)
478{
479 return group->id;
480}
481EXPORT_SYMBOL_GPL(iommu_group_id);
482
483static int add_iommu_group(struct device *dev, void *data)
484{
485 struct iommu_ops *ops = data;
486
487 if (!ops->add_device)
488 return -ENODEV;
489
490 WARN_ON(dev->iommu_group);
491
492 ops->add_device(dev);
493
494 return 0;
495}
496
497static int iommu_bus_notifier(struct notifier_block *nb,
498 unsigned long action, void *data)
499{
65 struct device *dev = data;
500 struct device *dev = data;
501 struct iommu_ops *ops = dev->bus->iommu_ops;
502 struct iommu_group *group;
503 unsigned long group_action = 0;
66
504
67 if (action == BUS_NOTIFY_ADD_DEVICE)
68 return add_iommu_group(dev, NULL);
69 else if (action == BUS_NOTIFY_DEL_DEVICE)
70 return remove_iommu_group(dev);
505 /*
506 * ADD/DEL call into iommu driver ops if provided, which may
507 * result in ADD/DEL notifiers to group->notifier
508 */
509 if (action == BUS_NOTIFY_ADD_DEVICE) {
510 if (ops->add_device)
511 return ops->add_device(dev);
512 } else if (action == BUS_NOTIFY_DEL_DEVICE) {
513 if (ops->remove_device && dev->iommu_group) {
514 ops->remove_device(dev);
515 return 0;
516 }
517 }
71
518
519 /*
520 * Remaining BUS_NOTIFYs get filtered and republished to the
521 * group, if anyone is listening
522 */
523 group = iommu_group_get(dev);
524 if (!group)
525 return 0;
526
527 switch (action) {
528 case BUS_NOTIFY_BIND_DRIVER:
529 group_action = IOMMU_GROUP_NOTIFY_BIND_DRIVER;
530 break;
531 case BUS_NOTIFY_BOUND_DRIVER:
532 group_action = IOMMU_GROUP_NOTIFY_BOUND_DRIVER;
533 break;
534 case BUS_NOTIFY_UNBIND_DRIVER:
535 group_action = IOMMU_GROUP_NOTIFY_UNBIND_DRIVER;
536 break;
537 case BUS_NOTIFY_UNBOUND_DRIVER:
538 group_action = IOMMU_GROUP_NOTIFY_UNBOUND_DRIVER;
539 break;
540 }
541
542 if (group_action)
543 blocking_notifier_call_chain(&group->notifier,
544 group_action, dev);
545
546 iommu_group_put(group);
72 return 0;
73}
74
547 return 0;
548}
549
75static struct notifier_block iommu_device_nb = {
76 .notifier_call = iommu_device_notifier,
550static struct notifier_block iommu_bus_nb = {
551 .notifier_call = iommu_bus_notifier,
77};
78
79static void iommu_bus_init(struct bus_type *bus, struct iommu_ops *ops)
80{
552};
553
554static void iommu_bus_init(struct bus_type *bus, struct iommu_ops *ops)
555{
81 bus_register_notifier(bus, &iommu_device_nb);
82 bus_for_each_dev(bus, NULL, NULL, add_iommu_group);
556 bus_register_notifier(bus, &iommu_bus_nb);
557 bus_for_each_dev(bus, NULL, ops, add_iommu_group);
83}
84
85/**
86 * bus_set_iommu - set iommu-callbacks for the bus
87 * @bus: bus.
88 * @ops: the callbacks provided by the iommu-driver
89 *
90 * This function is called by an iommu driver to set the iommu methods

--- 96 unchanged lines hidden (view full) ---

187{
188 if (unlikely(domain->ops->detach_dev == NULL))
189 return;
190
191 domain->ops->detach_dev(domain, dev);
192}
193EXPORT_SYMBOL_GPL(iommu_detach_device);
194
558}
559
560/**
561 * bus_set_iommu - set iommu-callbacks for the bus
562 * @bus: bus.
563 * @ops: the callbacks provided by the iommu-driver
564 *
565 * This function is called by an iommu driver to set the iommu methods

--- 96 unchanged lines hidden (view full) ---

662{
663 if (unlikely(domain->ops->detach_dev == NULL))
664 return;
665
666 domain->ops->detach_dev(domain, dev);
667}
668EXPORT_SYMBOL_GPL(iommu_detach_device);
669
670/*
671 * IOMMU groups are really the natrual working unit of the IOMMU, but
672 * the IOMMU API works on domains and devices. Bridge that gap by
673 * iterating over the devices in a group. Ideally we'd have a single
674 * device which represents the requestor ID of the group, but we also
675 * allow IOMMU drivers to create policy defined minimum sets, where
676 * the physical hardware may be able to distiguish members, but we
677 * wish to group them at a higher level (ex. untrusted multi-function
678 * PCI devices). Thus we attach each device.
679 */
680static int iommu_group_do_attach_device(struct device *dev, void *data)
681{
682 struct iommu_domain *domain = data;
683
684 return iommu_attach_device(domain, dev);
685}
686
687int iommu_attach_group(struct iommu_domain *domain, struct iommu_group *group)
688{
689 return iommu_group_for_each_dev(group, domain,
690 iommu_group_do_attach_device);
691}
692EXPORT_SYMBOL_GPL(iommu_attach_group);
693
694static int iommu_group_do_detach_device(struct device *dev, void *data)
695{
696 struct iommu_domain *domain = data;
697
698 iommu_detach_device(domain, dev);
699
700 return 0;
701}
702
703void iommu_detach_group(struct iommu_domain *domain, struct iommu_group *group)
704{
705 iommu_group_for_each_dev(group, domain, iommu_group_do_detach_device);
706}
707EXPORT_SYMBOL_GPL(iommu_detach_group);
708
195phys_addr_t iommu_iova_to_phys(struct iommu_domain *domain,
196 unsigned long iova)
197{
198 if (unlikely(domain->ops->iova_to_phys == NULL))
199 return 0;
200
201 return domain->ops->iova_to_phys(domain, iova);
202}

--- 128 unchanged lines hidden (view full) ---

331 iova += unmapped_page;
332 unmapped += unmapped_page;
333 }
334
335 return unmapped;
336}
337EXPORT_SYMBOL_GPL(iommu_unmap);
338
709phys_addr_t iommu_iova_to_phys(struct iommu_domain *domain,
710 unsigned long iova)
711{
712 if (unlikely(domain->ops->iova_to_phys == NULL))
713 return 0;
714
715 return domain->ops->iova_to_phys(domain, iova);
716}

--- 128 unchanged lines hidden (view full) ---

845 iova += unmapped_page;
846 unmapped += unmapped_page;
847 }
848
849 return unmapped;
850}
851EXPORT_SYMBOL_GPL(iommu_unmap);
852
339int iommu_device_group(struct device *dev, unsigned int *groupid)
853static int __init iommu_init(void)
340{
854{
341 if (iommu_present(dev->bus) && dev->bus->iommu_ops->device_group)
342 return dev->bus->iommu_ops->device_group(dev, groupid);
855 iommu_group_kset = kset_create_and_add("iommu_groups",
856 NULL, kernel_kobj);
857 ida_init(&iommu_group_ida);
858 mutex_init(&iommu_group_mutex);
343
859
344 return -ENODEV;
860 BUG_ON(!iommu_group_kset);
861
862 return 0;
345}
863}
346EXPORT_SYMBOL_GPL(iommu_device_group);
864subsys_initcall(iommu_init);