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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#include <linux/bug.h>
20#include <linux/types.h>
21#include <linux/module.h>
22#include <linux/slab.h>
23#include <linux/errno.h>
24#include <linux/iommu.h>
25
26static struct iommu_ops *iommu_ops;
27
28void register_iommu(struct iommu_ops *ops)
29{
30 if (iommu_ops)
31 BUG();
32
33 iommu_ops = ops;
34}
35
36bool iommu_found(void)
37{
38 return iommu_ops != NULL;
39}
40EXPORT_SYMBOL_GPL(iommu_found);
41
42struct iommu_domain *iommu_domain_alloc(void)
43{
44 struct iommu_domain *domain;
45 int ret;
46
47 domain = kmalloc(sizeof(*domain), GFP_KERNEL);
48 if (!domain)
49 return NULL;
50
51 ret = iommu_ops->domain_init(domain);
52 if (ret)
53 goto out_free;
54
55 return domain;
56
57out_free:
58 kfree(domain);
59
60 return NULL;
61}
62EXPORT_SYMBOL_GPL(iommu_domain_alloc);
63
64void iommu_domain_free(struct iommu_domain *domain)
65{
66 iommu_ops->domain_destroy(domain);
67 kfree(domain);
68}
69EXPORT_SYMBOL_GPL(iommu_domain_free);
70
71int iommu_attach_device(struct iommu_domain *domain, struct device *dev)
72{
73 return iommu_ops->attach_dev(domain, dev);
74}
75EXPORT_SYMBOL_GPL(iommu_attach_device);
76
77void iommu_detach_device(struct iommu_domain *domain, struct device *dev)
78{
79 iommu_ops->detach_dev(domain, dev);
80}
81EXPORT_SYMBOL_GPL(iommu_detach_device);
82
83phys_addr_t iommu_iova_to_phys(struct iommu_domain *domain,
84 unsigned long iova)
85{
86 return iommu_ops->iova_to_phys(domain, iova);
87}
88EXPORT_SYMBOL_GPL(iommu_iova_to_phys);
89
90int iommu_domain_has_cap(struct iommu_domain *domain,
91 unsigned long cap)
92{
93 return iommu_ops->domain_has_cap(domain, cap);
94}
95EXPORT_SYMBOL_GPL(iommu_domain_has_cap);
96
97int iommu_map(struct iommu_domain *domain, unsigned long iova,
98 phys_addr_t paddr, int gfp_order, int prot)
99{
100 unsigned long invalid_mask;
101 size_t size;
102
103 size = 0x1000UL << gfp_order;
104 invalid_mask = size - 1;
105
106 BUG_ON((iova | paddr) & invalid_mask);
107
108 return iommu_ops->map(domain, iova, paddr, gfp_order, prot);
109}
110EXPORT_SYMBOL_GPL(iommu_map);
111
112int iommu_unmap(struct iommu_domain *domain, unsigned long iova, int gfp_order)
113{
114 unsigned long invalid_mask;
115 size_t size;
116
117 size = 0x1000UL << gfp_order;
118 invalid_mask = size - 1;
119
120 BUG_ON(iova & invalid_mask);
121
122 return iommu_ops->unmap(domain, iova, gfp_order);
123}
124EXPORT_SYMBOL_GPL(iommu_unmap);
1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * Copyright (C) 2007-2008 Advanced Micro Devices, Inc.
4 * Author: Joerg Roedel <jroedel@suse.de>
5 */
6
7#define pr_fmt(fmt) "iommu: " fmt
8
9#include <linux/amba/bus.h>
10#include <linux/device.h>
11#include <linux/kernel.h>
12#include <linux/bits.h>
13#include <linux/bug.h>
14#include <linux/types.h>
15#include <linux/init.h>
16#include <linux/export.h>
17#include <linux/slab.h>
18#include <linux/errno.h>
19#include <linux/host1x_context_bus.h>
20#include <linux/iommu.h>
21#include <linux/idr.h>
22#include <linux/err.h>
23#include <linux/pci.h>
24#include <linux/pci-ats.h>
25#include <linux/bitops.h>
26#include <linux/platform_device.h>
27#include <linux/property.h>
28#include <linux/fsl/mc.h>
29#include <linux/module.h>
30#include <linux/cc_platform.h>
31#include <linux/cdx/cdx_bus.h>
32#include <trace/events/iommu.h>
33#include <linux/sched/mm.h>
34#include <linux/msi.h>
35
36#include "dma-iommu.h"
37#include "iommu-priv.h"
38
39#include "iommu-sva.h"
40
41static struct kset *iommu_group_kset;
42static DEFINE_IDA(iommu_group_ida);
43static DEFINE_IDA(iommu_global_pasid_ida);
44
45static unsigned int iommu_def_domain_type __read_mostly;
46static bool iommu_dma_strict __read_mostly = IS_ENABLED(CONFIG_IOMMU_DEFAULT_DMA_STRICT);
47static u32 iommu_cmd_line __read_mostly;
48
49struct iommu_group {
50 struct kobject kobj;
51 struct kobject *devices_kobj;
52 struct list_head devices;
53 struct xarray pasid_array;
54 struct mutex mutex;
55 void *iommu_data;
56 void (*iommu_data_release)(void *iommu_data);
57 char *name;
58 int id;
59 struct iommu_domain *default_domain;
60 struct iommu_domain *blocking_domain;
61 struct iommu_domain *domain;
62 struct list_head entry;
63 unsigned int owner_cnt;
64 void *owner;
65};
66
67struct group_device {
68 struct list_head list;
69 struct device *dev;
70 char *name;
71};
72
73/* Iterate over each struct group_device in a struct iommu_group */
74#define for_each_group_device(group, pos) \
75 list_for_each_entry(pos, &(group)->devices, list)
76
77struct iommu_group_attribute {
78 struct attribute attr;
79 ssize_t (*show)(struct iommu_group *group, char *buf);
80 ssize_t (*store)(struct iommu_group *group,
81 const char *buf, size_t count);
82};
83
84static const char * const iommu_group_resv_type_string[] = {
85 [IOMMU_RESV_DIRECT] = "direct",
86 [IOMMU_RESV_DIRECT_RELAXABLE] = "direct-relaxable",
87 [IOMMU_RESV_RESERVED] = "reserved",
88 [IOMMU_RESV_MSI] = "msi",
89 [IOMMU_RESV_SW_MSI] = "msi",
90};
91
92#define IOMMU_CMD_LINE_DMA_API BIT(0)
93#define IOMMU_CMD_LINE_STRICT BIT(1)
94
95static int iommu_bus_notifier(struct notifier_block *nb,
96 unsigned long action, void *data);
97static void iommu_release_device(struct device *dev);
98static struct iommu_domain *
99__iommu_group_domain_alloc(struct iommu_group *group, unsigned int type);
100static int __iommu_attach_device(struct iommu_domain *domain,
101 struct device *dev);
102static int __iommu_attach_group(struct iommu_domain *domain,
103 struct iommu_group *group);
104
105enum {
106 IOMMU_SET_DOMAIN_MUST_SUCCEED = 1 << 0,
107};
108
109static int __iommu_device_set_domain(struct iommu_group *group,
110 struct device *dev,
111 struct iommu_domain *new_domain,
112 unsigned int flags);
113static int __iommu_group_set_domain_internal(struct iommu_group *group,
114 struct iommu_domain *new_domain,
115 unsigned int flags);
116static int __iommu_group_set_domain(struct iommu_group *group,
117 struct iommu_domain *new_domain)
118{
119 return __iommu_group_set_domain_internal(group, new_domain, 0);
120}
121static void __iommu_group_set_domain_nofail(struct iommu_group *group,
122 struct iommu_domain *new_domain)
123{
124 WARN_ON(__iommu_group_set_domain_internal(
125 group, new_domain, IOMMU_SET_DOMAIN_MUST_SUCCEED));
126}
127
128static int iommu_setup_default_domain(struct iommu_group *group,
129 int target_type);
130static int iommu_create_device_direct_mappings(struct iommu_domain *domain,
131 struct device *dev);
132static ssize_t iommu_group_store_type(struct iommu_group *group,
133 const char *buf, size_t count);
134static struct group_device *iommu_group_alloc_device(struct iommu_group *group,
135 struct device *dev);
136static void __iommu_group_free_device(struct iommu_group *group,
137 struct group_device *grp_dev);
138
139#define IOMMU_GROUP_ATTR(_name, _mode, _show, _store) \
140struct iommu_group_attribute iommu_group_attr_##_name = \
141 __ATTR(_name, _mode, _show, _store)
142
143#define to_iommu_group_attr(_attr) \
144 container_of(_attr, struct iommu_group_attribute, attr)
145#define to_iommu_group(_kobj) \
146 container_of(_kobj, struct iommu_group, kobj)
147
148static LIST_HEAD(iommu_device_list);
149static DEFINE_SPINLOCK(iommu_device_lock);
150
151static const struct bus_type * const iommu_buses[] = {
152 &platform_bus_type,
153#ifdef CONFIG_PCI
154 &pci_bus_type,
155#endif
156#ifdef CONFIG_ARM_AMBA
157 &amba_bustype,
158#endif
159#ifdef CONFIG_FSL_MC_BUS
160 &fsl_mc_bus_type,
161#endif
162#ifdef CONFIG_TEGRA_HOST1X_CONTEXT_BUS
163 &host1x_context_device_bus_type,
164#endif
165#ifdef CONFIG_CDX_BUS
166 &cdx_bus_type,
167#endif
168};
169
170/*
171 * Use a function instead of an array here because the domain-type is a
172 * bit-field, so an array would waste memory.
173 */
174static const char *iommu_domain_type_str(unsigned int t)
175{
176 switch (t) {
177 case IOMMU_DOMAIN_BLOCKED:
178 return "Blocked";
179 case IOMMU_DOMAIN_IDENTITY:
180 return "Passthrough";
181 case IOMMU_DOMAIN_UNMANAGED:
182 return "Unmanaged";
183 case IOMMU_DOMAIN_DMA:
184 case IOMMU_DOMAIN_DMA_FQ:
185 return "Translated";
186 case IOMMU_DOMAIN_PLATFORM:
187 return "Platform";
188 default:
189 return "Unknown";
190 }
191}
192
193static int __init iommu_subsys_init(void)
194{
195 struct notifier_block *nb;
196
197 if (!(iommu_cmd_line & IOMMU_CMD_LINE_DMA_API)) {
198 if (IS_ENABLED(CONFIG_IOMMU_DEFAULT_PASSTHROUGH))
199 iommu_set_default_passthrough(false);
200 else
201 iommu_set_default_translated(false);
202
203 if (iommu_default_passthrough() && cc_platform_has(CC_ATTR_MEM_ENCRYPT)) {
204 pr_info("Memory encryption detected - Disabling default IOMMU Passthrough\n");
205 iommu_set_default_translated(false);
206 }
207 }
208
209 if (!iommu_default_passthrough() && !iommu_dma_strict)
210 iommu_def_domain_type = IOMMU_DOMAIN_DMA_FQ;
211
212 pr_info("Default domain type: %s%s\n",
213 iommu_domain_type_str(iommu_def_domain_type),
214 (iommu_cmd_line & IOMMU_CMD_LINE_DMA_API) ?
215 " (set via kernel command line)" : "");
216
217 if (!iommu_default_passthrough())
218 pr_info("DMA domain TLB invalidation policy: %s mode%s\n",
219 iommu_dma_strict ? "strict" : "lazy",
220 (iommu_cmd_line & IOMMU_CMD_LINE_STRICT) ?
221 " (set via kernel command line)" : "");
222
223 nb = kcalloc(ARRAY_SIZE(iommu_buses), sizeof(*nb), GFP_KERNEL);
224 if (!nb)
225 return -ENOMEM;
226
227 for (int i = 0; i < ARRAY_SIZE(iommu_buses); i++) {
228 nb[i].notifier_call = iommu_bus_notifier;
229 bus_register_notifier(iommu_buses[i], &nb[i]);
230 }
231
232 return 0;
233}
234subsys_initcall(iommu_subsys_init);
235
236static int remove_iommu_group(struct device *dev, void *data)
237{
238 if (dev->iommu && dev->iommu->iommu_dev == data)
239 iommu_release_device(dev);
240
241 return 0;
242}
243
244/**
245 * iommu_device_register() - Register an IOMMU hardware instance
246 * @iommu: IOMMU handle for the instance
247 * @ops: IOMMU ops to associate with the instance
248 * @hwdev: (optional) actual instance device, used for fwnode lookup
249 *
250 * Return: 0 on success, or an error.
251 */
252int iommu_device_register(struct iommu_device *iommu,
253 const struct iommu_ops *ops, struct device *hwdev)
254{
255 int err = 0;
256
257 /* We need to be able to take module references appropriately */
258 if (WARN_ON(is_module_address((unsigned long)ops) && !ops->owner))
259 return -EINVAL;
260
261 iommu->ops = ops;
262 if (hwdev)
263 iommu->fwnode = dev_fwnode(hwdev);
264
265 spin_lock(&iommu_device_lock);
266 list_add_tail(&iommu->list, &iommu_device_list);
267 spin_unlock(&iommu_device_lock);
268
269 for (int i = 0; i < ARRAY_SIZE(iommu_buses) && !err; i++)
270 err = bus_iommu_probe(iommu_buses[i]);
271 if (err)
272 iommu_device_unregister(iommu);
273 return err;
274}
275EXPORT_SYMBOL_GPL(iommu_device_register);
276
277void iommu_device_unregister(struct iommu_device *iommu)
278{
279 for (int i = 0; i < ARRAY_SIZE(iommu_buses); i++)
280 bus_for_each_dev(iommu_buses[i], NULL, iommu, remove_iommu_group);
281
282 spin_lock(&iommu_device_lock);
283 list_del(&iommu->list);
284 spin_unlock(&iommu_device_lock);
285
286 /* Pairs with the alloc in generic_single_device_group() */
287 iommu_group_put(iommu->singleton_group);
288 iommu->singleton_group = NULL;
289}
290EXPORT_SYMBOL_GPL(iommu_device_unregister);
291
292#if IS_ENABLED(CONFIG_IOMMUFD_TEST)
293void iommu_device_unregister_bus(struct iommu_device *iommu,
294 struct bus_type *bus,
295 struct notifier_block *nb)
296{
297 bus_unregister_notifier(bus, nb);
298 iommu_device_unregister(iommu);
299}
300EXPORT_SYMBOL_GPL(iommu_device_unregister_bus);
301
302/*
303 * Register an iommu driver against a single bus. This is only used by iommufd
304 * selftest to create a mock iommu driver. The caller must provide
305 * some memory to hold a notifier_block.
306 */
307int iommu_device_register_bus(struct iommu_device *iommu,
308 const struct iommu_ops *ops, struct bus_type *bus,
309 struct notifier_block *nb)
310{
311 int err;
312
313 iommu->ops = ops;
314 nb->notifier_call = iommu_bus_notifier;
315 err = bus_register_notifier(bus, nb);
316 if (err)
317 return err;
318
319 spin_lock(&iommu_device_lock);
320 list_add_tail(&iommu->list, &iommu_device_list);
321 spin_unlock(&iommu_device_lock);
322
323 err = bus_iommu_probe(bus);
324 if (err) {
325 iommu_device_unregister_bus(iommu, bus, nb);
326 return err;
327 }
328 return 0;
329}
330EXPORT_SYMBOL_GPL(iommu_device_register_bus);
331#endif
332
333static struct dev_iommu *dev_iommu_get(struct device *dev)
334{
335 struct dev_iommu *param = dev->iommu;
336
337 lockdep_assert_held(&iommu_probe_device_lock);
338
339 if (param)
340 return param;
341
342 param = kzalloc(sizeof(*param), GFP_KERNEL);
343 if (!param)
344 return NULL;
345
346 mutex_init(¶m->lock);
347 dev->iommu = param;
348 return param;
349}
350
351static void dev_iommu_free(struct device *dev)
352{
353 struct dev_iommu *param = dev->iommu;
354
355 dev->iommu = NULL;
356 if (param->fwspec) {
357 fwnode_handle_put(param->fwspec->iommu_fwnode);
358 kfree(param->fwspec);
359 }
360 kfree(param);
361}
362
363/*
364 * Internal equivalent of device_iommu_mapped() for when we care that a device
365 * actually has API ops, and don't want false positives from VFIO-only groups.
366 */
367static bool dev_has_iommu(struct device *dev)
368{
369 return dev->iommu && dev->iommu->iommu_dev;
370}
371
372static u32 dev_iommu_get_max_pasids(struct device *dev)
373{
374 u32 max_pasids = 0, bits = 0;
375 int ret;
376
377 if (dev_is_pci(dev)) {
378 ret = pci_max_pasids(to_pci_dev(dev));
379 if (ret > 0)
380 max_pasids = ret;
381 } else {
382 ret = device_property_read_u32(dev, "pasid-num-bits", &bits);
383 if (!ret)
384 max_pasids = 1UL << bits;
385 }
386
387 return min_t(u32, max_pasids, dev->iommu->iommu_dev->max_pasids);
388}
389
390void dev_iommu_priv_set(struct device *dev, void *priv)
391{
392 /* FSL_PAMU does something weird */
393 if (!IS_ENABLED(CONFIG_FSL_PAMU))
394 lockdep_assert_held(&iommu_probe_device_lock);
395 dev->iommu->priv = priv;
396}
397EXPORT_SYMBOL_GPL(dev_iommu_priv_set);
398
399/*
400 * Init the dev->iommu and dev->iommu_group in the struct device and get the
401 * driver probed
402 */
403static int iommu_init_device(struct device *dev, const struct iommu_ops *ops)
404{
405 struct iommu_device *iommu_dev;
406 struct iommu_group *group;
407 int ret;
408
409 if (!dev_iommu_get(dev))
410 return -ENOMEM;
411
412 if (!try_module_get(ops->owner)) {
413 ret = -EINVAL;
414 goto err_free;
415 }
416
417 iommu_dev = ops->probe_device(dev);
418 if (IS_ERR(iommu_dev)) {
419 ret = PTR_ERR(iommu_dev);
420 goto err_module_put;
421 }
422 dev->iommu->iommu_dev = iommu_dev;
423
424 ret = iommu_device_link(iommu_dev, dev);
425 if (ret)
426 goto err_release;
427
428 group = ops->device_group(dev);
429 if (WARN_ON_ONCE(group == NULL))
430 group = ERR_PTR(-EINVAL);
431 if (IS_ERR(group)) {
432 ret = PTR_ERR(group);
433 goto err_unlink;
434 }
435 dev->iommu_group = group;
436
437 dev->iommu->max_pasids = dev_iommu_get_max_pasids(dev);
438 if (ops->is_attach_deferred)
439 dev->iommu->attach_deferred = ops->is_attach_deferred(dev);
440 return 0;
441
442err_unlink:
443 iommu_device_unlink(iommu_dev, dev);
444err_release:
445 if (ops->release_device)
446 ops->release_device(dev);
447err_module_put:
448 module_put(ops->owner);
449err_free:
450 dev->iommu->iommu_dev = NULL;
451 dev_iommu_free(dev);
452 return ret;
453}
454
455static void iommu_deinit_device(struct device *dev)
456{
457 struct iommu_group *group = dev->iommu_group;
458 const struct iommu_ops *ops = dev_iommu_ops(dev);
459
460 lockdep_assert_held(&group->mutex);
461
462 iommu_device_unlink(dev->iommu->iommu_dev, dev);
463
464 /*
465 * release_device() must stop using any attached domain on the device.
466 * If there are still other devices in the group they are not effected
467 * by this callback.
468 *
469 * The IOMMU driver must set the device to either an identity or
470 * blocking translation and stop using any domain pointer, as it is
471 * going to be freed.
472 */
473 if (ops->release_device)
474 ops->release_device(dev);
475
476 /*
477 * If this is the last driver to use the group then we must free the
478 * domains before we do the module_put().
479 */
480 if (list_empty(&group->devices)) {
481 if (group->default_domain) {
482 iommu_domain_free(group->default_domain);
483 group->default_domain = NULL;
484 }
485 if (group->blocking_domain) {
486 iommu_domain_free(group->blocking_domain);
487 group->blocking_domain = NULL;
488 }
489 group->domain = NULL;
490 }
491
492 /* Caller must put iommu_group */
493 dev->iommu_group = NULL;
494 module_put(ops->owner);
495 dev_iommu_free(dev);
496}
497
498DEFINE_MUTEX(iommu_probe_device_lock);
499
500static int __iommu_probe_device(struct device *dev, struct list_head *group_list)
501{
502 const struct iommu_ops *ops;
503 struct iommu_fwspec *fwspec;
504 struct iommu_group *group;
505 struct group_device *gdev;
506 int ret;
507
508 /*
509 * For FDT-based systems and ACPI IORT/VIOT, drivers register IOMMU
510 * instances with non-NULL fwnodes, and client devices should have been
511 * identified with a fwspec by this point. Otherwise, we can currently
512 * assume that only one of Intel, AMD, s390, PAMU or legacy SMMUv2 can
513 * be present, and that any of their registered instances has suitable
514 * ops for probing, and thus cheekily co-opt the same mechanism.
515 */
516 fwspec = dev_iommu_fwspec_get(dev);
517 if (fwspec && fwspec->ops)
518 ops = fwspec->ops;
519 else
520 ops = iommu_ops_from_fwnode(NULL);
521
522 if (!ops)
523 return -ENODEV;
524 /*
525 * Serialise to avoid races between IOMMU drivers registering in
526 * parallel and/or the "replay" calls from ACPI/OF code via client
527 * driver probe. Once the latter have been cleaned up we should
528 * probably be able to use device_lock() here to minimise the scope,
529 * but for now enforcing a simple global ordering is fine.
530 */
531 lockdep_assert_held(&iommu_probe_device_lock);
532
533 /* Device is probed already if in a group */
534 if (dev->iommu_group)
535 return 0;
536
537 ret = iommu_init_device(dev, ops);
538 if (ret)
539 return ret;
540
541 group = dev->iommu_group;
542 gdev = iommu_group_alloc_device(group, dev);
543 mutex_lock(&group->mutex);
544 if (IS_ERR(gdev)) {
545 ret = PTR_ERR(gdev);
546 goto err_put_group;
547 }
548
549 /*
550 * The gdev must be in the list before calling
551 * iommu_setup_default_domain()
552 */
553 list_add_tail(&gdev->list, &group->devices);
554 WARN_ON(group->default_domain && !group->domain);
555 if (group->default_domain)
556 iommu_create_device_direct_mappings(group->default_domain, dev);
557 if (group->domain) {
558 ret = __iommu_device_set_domain(group, dev, group->domain, 0);
559 if (ret)
560 goto err_remove_gdev;
561 } else if (!group->default_domain && !group_list) {
562 ret = iommu_setup_default_domain(group, 0);
563 if (ret)
564 goto err_remove_gdev;
565 } else if (!group->default_domain) {
566 /*
567 * With a group_list argument we defer the default_domain setup
568 * to the caller by providing a de-duplicated list of groups
569 * that need further setup.
570 */
571 if (list_empty(&group->entry))
572 list_add_tail(&group->entry, group_list);
573 }
574 mutex_unlock(&group->mutex);
575
576 if (dev_is_pci(dev))
577 iommu_dma_set_pci_32bit_workaround(dev);
578
579 return 0;
580
581err_remove_gdev:
582 list_del(&gdev->list);
583 __iommu_group_free_device(group, gdev);
584err_put_group:
585 iommu_deinit_device(dev);
586 mutex_unlock(&group->mutex);
587 iommu_group_put(group);
588
589 return ret;
590}
591
592int iommu_probe_device(struct device *dev)
593{
594 const struct iommu_ops *ops;
595 int ret;
596
597 mutex_lock(&iommu_probe_device_lock);
598 ret = __iommu_probe_device(dev, NULL);
599 mutex_unlock(&iommu_probe_device_lock);
600 if (ret)
601 return ret;
602
603 ops = dev_iommu_ops(dev);
604 if (ops->probe_finalize)
605 ops->probe_finalize(dev);
606
607 return 0;
608}
609
610static void __iommu_group_free_device(struct iommu_group *group,
611 struct group_device *grp_dev)
612{
613 struct device *dev = grp_dev->dev;
614
615 sysfs_remove_link(group->devices_kobj, grp_dev->name);
616 sysfs_remove_link(&dev->kobj, "iommu_group");
617
618 trace_remove_device_from_group(group->id, dev);
619
620 /*
621 * If the group has become empty then ownership must have been
622 * released, and the current domain must be set back to NULL or
623 * the default domain.
624 */
625 if (list_empty(&group->devices))
626 WARN_ON(group->owner_cnt ||
627 group->domain != group->default_domain);
628
629 kfree(grp_dev->name);
630 kfree(grp_dev);
631}
632
633/* Remove the iommu_group from the struct device. */
634static void __iommu_group_remove_device(struct device *dev)
635{
636 struct iommu_group *group = dev->iommu_group;
637 struct group_device *device;
638
639 mutex_lock(&group->mutex);
640 for_each_group_device(group, device) {
641 if (device->dev != dev)
642 continue;
643
644 list_del(&device->list);
645 __iommu_group_free_device(group, device);
646 if (dev_has_iommu(dev))
647 iommu_deinit_device(dev);
648 else
649 dev->iommu_group = NULL;
650 break;
651 }
652 mutex_unlock(&group->mutex);
653
654 /*
655 * Pairs with the get in iommu_init_device() or
656 * iommu_group_add_device()
657 */
658 iommu_group_put(group);
659}
660
661static void iommu_release_device(struct device *dev)
662{
663 struct iommu_group *group = dev->iommu_group;
664
665 if (group)
666 __iommu_group_remove_device(dev);
667
668 /* Free any fwspec if no iommu_driver was ever attached */
669 if (dev->iommu)
670 dev_iommu_free(dev);
671}
672
673static int __init iommu_set_def_domain_type(char *str)
674{
675 bool pt;
676 int ret;
677
678 ret = kstrtobool(str, &pt);
679 if (ret)
680 return ret;
681
682 if (pt)
683 iommu_set_default_passthrough(true);
684 else
685 iommu_set_default_translated(true);
686
687 return 0;
688}
689early_param("iommu.passthrough", iommu_set_def_domain_type);
690
691static int __init iommu_dma_setup(char *str)
692{
693 int ret = kstrtobool(str, &iommu_dma_strict);
694
695 if (!ret)
696 iommu_cmd_line |= IOMMU_CMD_LINE_STRICT;
697 return ret;
698}
699early_param("iommu.strict", iommu_dma_setup);
700
701void iommu_set_dma_strict(void)
702{
703 iommu_dma_strict = true;
704 if (iommu_def_domain_type == IOMMU_DOMAIN_DMA_FQ)
705 iommu_def_domain_type = IOMMU_DOMAIN_DMA;
706}
707
708static ssize_t iommu_group_attr_show(struct kobject *kobj,
709 struct attribute *__attr, char *buf)
710{
711 struct iommu_group_attribute *attr = to_iommu_group_attr(__attr);
712 struct iommu_group *group = to_iommu_group(kobj);
713 ssize_t ret = -EIO;
714
715 if (attr->show)
716 ret = attr->show(group, buf);
717 return ret;
718}
719
720static ssize_t iommu_group_attr_store(struct kobject *kobj,
721 struct attribute *__attr,
722 const char *buf, size_t count)
723{
724 struct iommu_group_attribute *attr = to_iommu_group_attr(__attr);
725 struct iommu_group *group = to_iommu_group(kobj);
726 ssize_t ret = -EIO;
727
728 if (attr->store)
729 ret = attr->store(group, buf, count);
730 return ret;
731}
732
733static const struct sysfs_ops iommu_group_sysfs_ops = {
734 .show = iommu_group_attr_show,
735 .store = iommu_group_attr_store,
736};
737
738static int iommu_group_create_file(struct iommu_group *group,
739 struct iommu_group_attribute *attr)
740{
741 return sysfs_create_file(&group->kobj, &attr->attr);
742}
743
744static void iommu_group_remove_file(struct iommu_group *group,
745 struct iommu_group_attribute *attr)
746{
747 sysfs_remove_file(&group->kobj, &attr->attr);
748}
749
750static ssize_t iommu_group_show_name(struct iommu_group *group, char *buf)
751{
752 return sysfs_emit(buf, "%s\n", group->name);
753}
754
755/**
756 * iommu_insert_resv_region - Insert a new region in the
757 * list of reserved regions.
758 * @new: new region to insert
759 * @regions: list of regions
760 *
761 * Elements are sorted by start address and overlapping segments
762 * of the same type are merged.
763 */
764static int iommu_insert_resv_region(struct iommu_resv_region *new,
765 struct list_head *regions)
766{
767 struct iommu_resv_region *iter, *tmp, *nr, *top;
768 LIST_HEAD(stack);
769
770 nr = iommu_alloc_resv_region(new->start, new->length,
771 new->prot, new->type, GFP_KERNEL);
772 if (!nr)
773 return -ENOMEM;
774
775 /* First add the new element based on start address sorting */
776 list_for_each_entry(iter, regions, list) {
777 if (nr->start < iter->start ||
778 (nr->start == iter->start && nr->type <= iter->type))
779 break;
780 }
781 list_add_tail(&nr->list, &iter->list);
782
783 /* Merge overlapping segments of type nr->type in @regions, if any */
784 list_for_each_entry_safe(iter, tmp, regions, list) {
785 phys_addr_t top_end, iter_end = iter->start + iter->length - 1;
786
787 /* no merge needed on elements of different types than @new */
788 if (iter->type != new->type) {
789 list_move_tail(&iter->list, &stack);
790 continue;
791 }
792
793 /* look for the last stack element of same type as @iter */
794 list_for_each_entry_reverse(top, &stack, list)
795 if (top->type == iter->type)
796 goto check_overlap;
797
798 list_move_tail(&iter->list, &stack);
799 continue;
800
801check_overlap:
802 top_end = top->start + top->length - 1;
803
804 if (iter->start > top_end + 1) {
805 list_move_tail(&iter->list, &stack);
806 } else {
807 top->length = max(top_end, iter_end) - top->start + 1;
808 list_del(&iter->list);
809 kfree(iter);
810 }
811 }
812 list_splice(&stack, regions);
813 return 0;
814}
815
816static int
817iommu_insert_device_resv_regions(struct list_head *dev_resv_regions,
818 struct list_head *group_resv_regions)
819{
820 struct iommu_resv_region *entry;
821 int ret = 0;
822
823 list_for_each_entry(entry, dev_resv_regions, list) {
824 ret = iommu_insert_resv_region(entry, group_resv_regions);
825 if (ret)
826 break;
827 }
828 return ret;
829}
830
831int iommu_get_group_resv_regions(struct iommu_group *group,
832 struct list_head *head)
833{
834 struct group_device *device;
835 int ret = 0;
836
837 mutex_lock(&group->mutex);
838 for_each_group_device(group, device) {
839 struct list_head dev_resv_regions;
840
841 /*
842 * Non-API groups still expose reserved_regions in sysfs,
843 * so filter out calls that get here that way.
844 */
845 if (!dev_has_iommu(device->dev))
846 break;
847
848 INIT_LIST_HEAD(&dev_resv_regions);
849 iommu_get_resv_regions(device->dev, &dev_resv_regions);
850 ret = iommu_insert_device_resv_regions(&dev_resv_regions, head);
851 iommu_put_resv_regions(device->dev, &dev_resv_regions);
852 if (ret)
853 break;
854 }
855 mutex_unlock(&group->mutex);
856 return ret;
857}
858EXPORT_SYMBOL_GPL(iommu_get_group_resv_regions);
859
860static ssize_t iommu_group_show_resv_regions(struct iommu_group *group,
861 char *buf)
862{
863 struct iommu_resv_region *region, *next;
864 struct list_head group_resv_regions;
865 int offset = 0;
866
867 INIT_LIST_HEAD(&group_resv_regions);
868 iommu_get_group_resv_regions(group, &group_resv_regions);
869
870 list_for_each_entry_safe(region, next, &group_resv_regions, list) {
871 offset += sysfs_emit_at(buf, offset, "0x%016llx 0x%016llx %s\n",
872 (long long)region->start,
873 (long long)(region->start +
874 region->length - 1),
875 iommu_group_resv_type_string[region->type]);
876 kfree(region);
877 }
878
879 return offset;
880}
881
882static ssize_t iommu_group_show_type(struct iommu_group *group,
883 char *buf)
884{
885 char *type = "unknown";
886
887 mutex_lock(&group->mutex);
888 if (group->default_domain) {
889 switch (group->default_domain->type) {
890 case IOMMU_DOMAIN_BLOCKED:
891 type = "blocked";
892 break;
893 case IOMMU_DOMAIN_IDENTITY:
894 type = "identity";
895 break;
896 case IOMMU_DOMAIN_UNMANAGED:
897 type = "unmanaged";
898 break;
899 case IOMMU_DOMAIN_DMA:
900 type = "DMA";
901 break;
902 case IOMMU_DOMAIN_DMA_FQ:
903 type = "DMA-FQ";
904 break;
905 }
906 }
907 mutex_unlock(&group->mutex);
908
909 return sysfs_emit(buf, "%s\n", type);
910}
911
912static IOMMU_GROUP_ATTR(name, S_IRUGO, iommu_group_show_name, NULL);
913
914static IOMMU_GROUP_ATTR(reserved_regions, 0444,
915 iommu_group_show_resv_regions, NULL);
916
917static IOMMU_GROUP_ATTR(type, 0644, iommu_group_show_type,
918 iommu_group_store_type);
919
920static void iommu_group_release(struct kobject *kobj)
921{
922 struct iommu_group *group = to_iommu_group(kobj);
923
924 pr_debug("Releasing group %d\n", group->id);
925
926 if (group->iommu_data_release)
927 group->iommu_data_release(group->iommu_data);
928
929 ida_free(&iommu_group_ida, group->id);
930
931 /* Domains are free'd by iommu_deinit_device() */
932 WARN_ON(group->default_domain);
933 WARN_ON(group->blocking_domain);
934
935 kfree(group->name);
936 kfree(group);
937}
938
939static const struct kobj_type iommu_group_ktype = {
940 .sysfs_ops = &iommu_group_sysfs_ops,
941 .release = iommu_group_release,
942};
943
944/**
945 * iommu_group_alloc - Allocate a new group
946 *
947 * This function is called by an iommu driver to allocate a new iommu
948 * group. The iommu group represents the minimum granularity of the iommu.
949 * Upon successful return, the caller holds a reference to the supplied
950 * group in order to hold the group until devices are added. Use
951 * iommu_group_put() to release this extra reference count, allowing the
952 * group to be automatically reclaimed once it has no devices or external
953 * references.
954 */
955struct iommu_group *iommu_group_alloc(void)
956{
957 struct iommu_group *group;
958 int ret;
959
960 group = kzalloc(sizeof(*group), GFP_KERNEL);
961 if (!group)
962 return ERR_PTR(-ENOMEM);
963
964 group->kobj.kset = iommu_group_kset;
965 mutex_init(&group->mutex);
966 INIT_LIST_HEAD(&group->devices);
967 INIT_LIST_HEAD(&group->entry);
968 xa_init(&group->pasid_array);
969
970 ret = ida_alloc(&iommu_group_ida, GFP_KERNEL);
971 if (ret < 0) {
972 kfree(group);
973 return ERR_PTR(ret);
974 }
975 group->id = ret;
976
977 ret = kobject_init_and_add(&group->kobj, &iommu_group_ktype,
978 NULL, "%d", group->id);
979 if (ret) {
980 kobject_put(&group->kobj);
981 return ERR_PTR(ret);
982 }
983
984 group->devices_kobj = kobject_create_and_add("devices", &group->kobj);
985 if (!group->devices_kobj) {
986 kobject_put(&group->kobj); /* triggers .release & free */
987 return ERR_PTR(-ENOMEM);
988 }
989
990 /*
991 * The devices_kobj holds a reference on the group kobject, so
992 * as long as that exists so will the group. We can therefore
993 * use the devices_kobj for reference counting.
994 */
995 kobject_put(&group->kobj);
996
997 ret = iommu_group_create_file(group,
998 &iommu_group_attr_reserved_regions);
999 if (ret) {
1000 kobject_put(group->devices_kobj);
1001 return ERR_PTR(ret);
1002 }
1003
1004 ret = iommu_group_create_file(group, &iommu_group_attr_type);
1005 if (ret) {
1006 kobject_put(group->devices_kobj);
1007 return ERR_PTR(ret);
1008 }
1009
1010 pr_debug("Allocated group %d\n", group->id);
1011
1012 return group;
1013}
1014EXPORT_SYMBOL_GPL(iommu_group_alloc);
1015
1016/**
1017 * iommu_group_get_iommudata - retrieve iommu_data registered for a group
1018 * @group: the group
1019 *
1020 * iommu drivers can store data in the group for use when doing iommu
1021 * operations. This function provides a way to retrieve it. Caller
1022 * should hold a group reference.
1023 */
1024void *iommu_group_get_iommudata(struct iommu_group *group)
1025{
1026 return group->iommu_data;
1027}
1028EXPORT_SYMBOL_GPL(iommu_group_get_iommudata);
1029
1030/**
1031 * iommu_group_set_iommudata - set iommu_data for a group
1032 * @group: the group
1033 * @iommu_data: new data
1034 * @release: release function for iommu_data
1035 *
1036 * iommu drivers can store data in the group for use when doing iommu
1037 * operations. This function provides a way to set the data after
1038 * the group has been allocated. Caller should hold a group reference.
1039 */
1040void iommu_group_set_iommudata(struct iommu_group *group, void *iommu_data,
1041 void (*release)(void *iommu_data))
1042{
1043 group->iommu_data = iommu_data;
1044 group->iommu_data_release = release;
1045}
1046EXPORT_SYMBOL_GPL(iommu_group_set_iommudata);
1047
1048/**
1049 * iommu_group_set_name - set name for a group
1050 * @group: the group
1051 * @name: name
1052 *
1053 * Allow iommu driver to set a name for a group. When set it will
1054 * appear in a name attribute file under the group in sysfs.
1055 */
1056int iommu_group_set_name(struct iommu_group *group, const char *name)
1057{
1058 int ret;
1059
1060 if (group->name) {
1061 iommu_group_remove_file(group, &iommu_group_attr_name);
1062 kfree(group->name);
1063 group->name = NULL;
1064 if (!name)
1065 return 0;
1066 }
1067
1068 group->name = kstrdup(name, GFP_KERNEL);
1069 if (!group->name)
1070 return -ENOMEM;
1071
1072 ret = iommu_group_create_file(group, &iommu_group_attr_name);
1073 if (ret) {
1074 kfree(group->name);
1075 group->name = NULL;
1076 return ret;
1077 }
1078
1079 return 0;
1080}
1081EXPORT_SYMBOL_GPL(iommu_group_set_name);
1082
1083static int iommu_create_device_direct_mappings(struct iommu_domain *domain,
1084 struct device *dev)
1085{
1086 struct iommu_resv_region *entry;
1087 struct list_head mappings;
1088 unsigned long pg_size;
1089 int ret = 0;
1090
1091 pg_size = domain->pgsize_bitmap ? 1UL << __ffs(domain->pgsize_bitmap) : 0;
1092 INIT_LIST_HEAD(&mappings);
1093
1094 if (WARN_ON_ONCE(iommu_is_dma_domain(domain) && !pg_size))
1095 return -EINVAL;
1096
1097 iommu_get_resv_regions(dev, &mappings);
1098
1099 /* We need to consider overlapping regions for different devices */
1100 list_for_each_entry(entry, &mappings, list) {
1101 dma_addr_t start, end, addr;
1102 size_t map_size = 0;
1103
1104 if (entry->type == IOMMU_RESV_DIRECT)
1105 dev->iommu->require_direct = 1;
1106
1107 if ((entry->type != IOMMU_RESV_DIRECT &&
1108 entry->type != IOMMU_RESV_DIRECT_RELAXABLE) ||
1109 !iommu_is_dma_domain(domain))
1110 continue;
1111
1112 start = ALIGN(entry->start, pg_size);
1113 end = ALIGN(entry->start + entry->length, pg_size);
1114
1115 for (addr = start; addr <= end; addr += pg_size) {
1116 phys_addr_t phys_addr;
1117
1118 if (addr == end)
1119 goto map_end;
1120
1121 phys_addr = iommu_iova_to_phys(domain, addr);
1122 if (!phys_addr) {
1123 map_size += pg_size;
1124 continue;
1125 }
1126
1127map_end:
1128 if (map_size) {
1129 ret = iommu_map(domain, addr - map_size,
1130 addr - map_size, map_size,
1131 entry->prot, GFP_KERNEL);
1132 if (ret)
1133 goto out;
1134 map_size = 0;
1135 }
1136 }
1137
1138 }
1139
1140 if (!list_empty(&mappings) && iommu_is_dma_domain(domain))
1141 iommu_flush_iotlb_all(domain);
1142
1143out:
1144 iommu_put_resv_regions(dev, &mappings);
1145
1146 return ret;
1147}
1148
1149/* This is undone by __iommu_group_free_device() */
1150static struct group_device *iommu_group_alloc_device(struct iommu_group *group,
1151 struct device *dev)
1152{
1153 int ret, i = 0;
1154 struct group_device *device;
1155
1156 device = kzalloc(sizeof(*device), GFP_KERNEL);
1157 if (!device)
1158 return ERR_PTR(-ENOMEM);
1159
1160 device->dev = dev;
1161
1162 ret = sysfs_create_link(&dev->kobj, &group->kobj, "iommu_group");
1163 if (ret)
1164 goto err_free_device;
1165
1166 device->name = kasprintf(GFP_KERNEL, "%s", kobject_name(&dev->kobj));
1167rename:
1168 if (!device->name) {
1169 ret = -ENOMEM;
1170 goto err_remove_link;
1171 }
1172
1173 ret = sysfs_create_link_nowarn(group->devices_kobj,
1174 &dev->kobj, device->name);
1175 if (ret) {
1176 if (ret == -EEXIST && i >= 0) {
1177 /*
1178 * Account for the slim chance of collision
1179 * and append an instance to the name.
1180 */
1181 kfree(device->name);
1182 device->name = kasprintf(GFP_KERNEL, "%s.%d",
1183 kobject_name(&dev->kobj), i++);
1184 goto rename;
1185 }
1186 goto err_free_name;
1187 }
1188
1189 trace_add_device_to_group(group->id, dev);
1190
1191 dev_info(dev, "Adding to iommu group %d\n", group->id);
1192
1193 return device;
1194
1195err_free_name:
1196 kfree(device->name);
1197err_remove_link:
1198 sysfs_remove_link(&dev->kobj, "iommu_group");
1199err_free_device:
1200 kfree(device);
1201 dev_err(dev, "Failed to add to iommu group %d: %d\n", group->id, ret);
1202 return ERR_PTR(ret);
1203}
1204
1205/**
1206 * iommu_group_add_device - add a device to an iommu group
1207 * @group: the group into which to add the device (reference should be held)
1208 * @dev: the device
1209 *
1210 * This function is called by an iommu driver to add a device into a
1211 * group. Adding a device increments the group reference count.
1212 */
1213int iommu_group_add_device(struct iommu_group *group, struct device *dev)
1214{
1215 struct group_device *gdev;
1216
1217 gdev = iommu_group_alloc_device(group, dev);
1218 if (IS_ERR(gdev))
1219 return PTR_ERR(gdev);
1220
1221 iommu_group_ref_get(group);
1222 dev->iommu_group = group;
1223
1224 mutex_lock(&group->mutex);
1225 list_add_tail(&gdev->list, &group->devices);
1226 mutex_unlock(&group->mutex);
1227 return 0;
1228}
1229EXPORT_SYMBOL_GPL(iommu_group_add_device);
1230
1231/**
1232 * iommu_group_remove_device - remove a device from it's current group
1233 * @dev: device to be removed
1234 *
1235 * This function is called by an iommu driver to remove the device from
1236 * it's current group. This decrements the iommu group reference count.
1237 */
1238void iommu_group_remove_device(struct device *dev)
1239{
1240 struct iommu_group *group = dev->iommu_group;
1241
1242 if (!group)
1243 return;
1244
1245 dev_info(dev, "Removing from iommu group %d\n", group->id);
1246
1247 __iommu_group_remove_device(dev);
1248}
1249EXPORT_SYMBOL_GPL(iommu_group_remove_device);
1250
1251static struct device *iommu_group_first_dev(struct iommu_group *group)
1252{
1253 lockdep_assert_held(&group->mutex);
1254 return list_first_entry(&group->devices, struct group_device, list)->dev;
1255}
1256
1257/**
1258 * iommu_group_for_each_dev - iterate over each device in the group
1259 * @group: the group
1260 * @data: caller opaque data to be passed to callback function
1261 * @fn: caller supplied callback function
1262 *
1263 * This function is called by group users to iterate over group devices.
1264 * Callers should hold a reference count to the group during callback.
1265 * The group->mutex is held across callbacks, which will block calls to
1266 * iommu_group_add/remove_device.
1267 */
1268int iommu_group_for_each_dev(struct iommu_group *group, void *data,
1269 int (*fn)(struct device *, void *))
1270{
1271 struct group_device *device;
1272 int ret = 0;
1273
1274 mutex_lock(&group->mutex);
1275 for_each_group_device(group, device) {
1276 ret = fn(device->dev, data);
1277 if (ret)
1278 break;
1279 }
1280 mutex_unlock(&group->mutex);
1281
1282 return ret;
1283}
1284EXPORT_SYMBOL_GPL(iommu_group_for_each_dev);
1285
1286/**
1287 * iommu_group_get - Return the group for a device and increment reference
1288 * @dev: get the group that this device belongs to
1289 *
1290 * This function is called by iommu drivers and users to get the group
1291 * for the specified device. If found, the group is returned and the group
1292 * reference in incremented, else NULL.
1293 */
1294struct iommu_group *iommu_group_get(struct device *dev)
1295{
1296 struct iommu_group *group = dev->iommu_group;
1297
1298 if (group)
1299 kobject_get(group->devices_kobj);
1300
1301 return group;
1302}
1303EXPORT_SYMBOL_GPL(iommu_group_get);
1304
1305/**
1306 * iommu_group_ref_get - Increment reference on a group
1307 * @group: the group to use, must not be NULL
1308 *
1309 * This function is called by iommu drivers to take additional references on an
1310 * existing group. Returns the given group for convenience.
1311 */
1312struct iommu_group *iommu_group_ref_get(struct iommu_group *group)
1313{
1314 kobject_get(group->devices_kobj);
1315 return group;
1316}
1317EXPORT_SYMBOL_GPL(iommu_group_ref_get);
1318
1319/**
1320 * iommu_group_put - Decrement group reference
1321 * @group: the group to use
1322 *
1323 * This function is called by iommu drivers and users to release the
1324 * iommu group. Once the reference count is zero, the group is released.
1325 */
1326void iommu_group_put(struct iommu_group *group)
1327{
1328 if (group)
1329 kobject_put(group->devices_kobj);
1330}
1331EXPORT_SYMBOL_GPL(iommu_group_put);
1332
1333/**
1334 * iommu_register_device_fault_handler() - Register a device fault handler
1335 * @dev: the device
1336 * @handler: the fault handler
1337 * @data: private data passed as argument to the handler
1338 *
1339 * When an IOMMU fault event is received, this handler gets called with the
1340 * fault event and data as argument. The handler should return 0 on success. If
1341 * the fault is recoverable (IOMMU_FAULT_PAGE_REQ), the consumer should also
1342 * complete the fault by calling iommu_page_response() with one of the following
1343 * response code:
1344 * - IOMMU_PAGE_RESP_SUCCESS: retry the translation
1345 * - IOMMU_PAGE_RESP_INVALID: terminate the fault
1346 * - IOMMU_PAGE_RESP_FAILURE: terminate the fault and stop reporting
1347 * page faults if possible.
1348 *
1349 * Return 0 if the fault handler was installed successfully, or an error.
1350 */
1351int iommu_register_device_fault_handler(struct device *dev,
1352 iommu_dev_fault_handler_t handler,
1353 void *data)
1354{
1355 struct dev_iommu *param = dev->iommu;
1356 int ret = 0;
1357
1358 if (!param)
1359 return -EINVAL;
1360
1361 mutex_lock(¶m->lock);
1362 /* Only allow one fault handler registered for each device */
1363 if (param->fault_param) {
1364 ret = -EBUSY;
1365 goto done_unlock;
1366 }
1367
1368 get_device(dev);
1369 param->fault_param = kzalloc(sizeof(*param->fault_param), GFP_KERNEL);
1370 if (!param->fault_param) {
1371 put_device(dev);
1372 ret = -ENOMEM;
1373 goto done_unlock;
1374 }
1375 param->fault_param->handler = handler;
1376 param->fault_param->data = data;
1377 mutex_init(¶m->fault_param->lock);
1378 INIT_LIST_HEAD(¶m->fault_param->faults);
1379
1380done_unlock:
1381 mutex_unlock(¶m->lock);
1382
1383 return ret;
1384}
1385EXPORT_SYMBOL_GPL(iommu_register_device_fault_handler);
1386
1387/**
1388 * iommu_unregister_device_fault_handler() - Unregister the device fault handler
1389 * @dev: the device
1390 *
1391 * Remove the device fault handler installed with
1392 * iommu_register_device_fault_handler().
1393 *
1394 * Return 0 on success, or an error.
1395 */
1396int iommu_unregister_device_fault_handler(struct device *dev)
1397{
1398 struct dev_iommu *param = dev->iommu;
1399 int ret = 0;
1400
1401 if (!param)
1402 return -EINVAL;
1403
1404 mutex_lock(¶m->lock);
1405
1406 if (!param->fault_param)
1407 goto unlock;
1408
1409 /* we cannot unregister handler if there are pending faults */
1410 if (!list_empty(¶m->fault_param->faults)) {
1411 ret = -EBUSY;
1412 goto unlock;
1413 }
1414
1415 kfree(param->fault_param);
1416 param->fault_param = NULL;
1417 put_device(dev);
1418unlock:
1419 mutex_unlock(¶m->lock);
1420
1421 return ret;
1422}
1423EXPORT_SYMBOL_GPL(iommu_unregister_device_fault_handler);
1424
1425/**
1426 * iommu_report_device_fault() - Report fault event to device driver
1427 * @dev: the device
1428 * @evt: fault event data
1429 *
1430 * Called by IOMMU drivers when a fault is detected, typically in a threaded IRQ
1431 * handler. When this function fails and the fault is recoverable, it is the
1432 * caller's responsibility to complete the fault.
1433 *
1434 * Return 0 on success, or an error.
1435 */
1436int iommu_report_device_fault(struct device *dev, struct iommu_fault_event *evt)
1437{
1438 struct dev_iommu *param = dev->iommu;
1439 struct iommu_fault_event *evt_pending = NULL;
1440 struct iommu_fault_param *fparam;
1441 int ret = 0;
1442
1443 if (!param || !evt)
1444 return -EINVAL;
1445
1446 /* we only report device fault if there is a handler registered */
1447 mutex_lock(¶m->lock);
1448 fparam = param->fault_param;
1449 if (!fparam || !fparam->handler) {
1450 ret = -EINVAL;
1451 goto done_unlock;
1452 }
1453
1454 if (evt->fault.type == IOMMU_FAULT_PAGE_REQ &&
1455 (evt->fault.prm.flags & IOMMU_FAULT_PAGE_REQUEST_LAST_PAGE)) {
1456 evt_pending = kmemdup(evt, sizeof(struct iommu_fault_event),
1457 GFP_KERNEL);
1458 if (!evt_pending) {
1459 ret = -ENOMEM;
1460 goto done_unlock;
1461 }
1462 mutex_lock(&fparam->lock);
1463 list_add_tail(&evt_pending->list, &fparam->faults);
1464 mutex_unlock(&fparam->lock);
1465 }
1466
1467 ret = fparam->handler(&evt->fault, fparam->data);
1468 if (ret && evt_pending) {
1469 mutex_lock(&fparam->lock);
1470 list_del(&evt_pending->list);
1471 mutex_unlock(&fparam->lock);
1472 kfree(evt_pending);
1473 }
1474done_unlock:
1475 mutex_unlock(¶m->lock);
1476 return ret;
1477}
1478EXPORT_SYMBOL_GPL(iommu_report_device_fault);
1479
1480int iommu_page_response(struct device *dev,
1481 struct iommu_page_response *msg)
1482{
1483 bool needs_pasid;
1484 int ret = -EINVAL;
1485 struct iommu_fault_event *evt;
1486 struct iommu_fault_page_request *prm;
1487 struct dev_iommu *param = dev->iommu;
1488 const struct iommu_ops *ops = dev_iommu_ops(dev);
1489 bool has_pasid = msg->flags & IOMMU_PAGE_RESP_PASID_VALID;
1490
1491 if (!ops->page_response)
1492 return -ENODEV;
1493
1494 if (!param || !param->fault_param)
1495 return -EINVAL;
1496
1497 if (msg->version != IOMMU_PAGE_RESP_VERSION_1 ||
1498 msg->flags & ~IOMMU_PAGE_RESP_PASID_VALID)
1499 return -EINVAL;
1500
1501 /* Only send response if there is a fault report pending */
1502 mutex_lock(¶m->fault_param->lock);
1503 if (list_empty(¶m->fault_param->faults)) {
1504 dev_warn_ratelimited(dev, "no pending PRQ, drop response\n");
1505 goto done_unlock;
1506 }
1507 /*
1508 * Check if we have a matching page request pending to respond,
1509 * otherwise return -EINVAL
1510 */
1511 list_for_each_entry(evt, ¶m->fault_param->faults, list) {
1512 prm = &evt->fault.prm;
1513 if (prm->grpid != msg->grpid)
1514 continue;
1515
1516 /*
1517 * If the PASID is required, the corresponding request is
1518 * matched using the group ID, the PASID valid bit and the PASID
1519 * value. Otherwise only the group ID matches request and
1520 * response.
1521 */
1522 needs_pasid = prm->flags & IOMMU_FAULT_PAGE_RESPONSE_NEEDS_PASID;
1523 if (needs_pasid && (!has_pasid || msg->pasid != prm->pasid))
1524 continue;
1525
1526 if (!needs_pasid && has_pasid) {
1527 /* No big deal, just clear it. */
1528 msg->flags &= ~IOMMU_PAGE_RESP_PASID_VALID;
1529 msg->pasid = 0;
1530 }
1531
1532 ret = ops->page_response(dev, evt, msg);
1533 list_del(&evt->list);
1534 kfree(evt);
1535 break;
1536 }
1537
1538done_unlock:
1539 mutex_unlock(¶m->fault_param->lock);
1540 return ret;
1541}
1542EXPORT_SYMBOL_GPL(iommu_page_response);
1543
1544/**
1545 * iommu_group_id - Return ID for a group
1546 * @group: the group to ID
1547 *
1548 * Return the unique ID for the group matching the sysfs group number.
1549 */
1550int iommu_group_id(struct iommu_group *group)
1551{
1552 return group->id;
1553}
1554EXPORT_SYMBOL_GPL(iommu_group_id);
1555
1556static struct iommu_group *get_pci_alias_group(struct pci_dev *pdev,
1557 unsigned long *devfns);
1558
1559/*
1560 * To consider a PCI device isolated, we require ACS to support Source
1561 * Validation, Request Redirection, Completer Redirection, and Upstream
1562 * Forwarding. This effectively means that devices cannot spoof their
1563 * requester ID, requests and completions cannot be redirected, and all
1564 * transactions are forwarded upstream, even as it passes through a
1565 * bridge where the target device is downstream.
1566 */
1567#define REQ_ACS_FLAGS (PCI_ACS_SV | PCI_ACS_RR | PCI_ACS_CR | PCI_ACS_UF)
1568
1569/*
1570 * For multifunction devices which are not isolated from each other, find
1571 * all the other non-isolated functions and look for existing groups. For
1572 * each function, we also need to look for aliases to or from other devices
1573 * that may already have a group.
1574 */
1575static struct iommu_group *get_pci_function_alias_group(struct pci_dev *pdev,
1576 unsigned long *devfns)
1577{
1578 struct pci_dev *tmp = NULL;
1579 struct iommu_group *group;
1580
1581 if (!pdev->multifunction || pci_acs_enabled(pdev, REQ_ACS_FLAGS))
1582 return NULL;
1583
1584 for_each_pci_dev(tmp) {
1585 if (tmp == pdev || tmp->bus != pdev->bus ||
1586 PCI_SLOT(tmp->devfn) != PCI_SLOT(pdev->devfn) ||
1587 pci_acs_enabled(tmp, REQ_ACS_FLAGS))
1588 continue;
1589
1590 group = get_pci_alias_group(tmp, devfns);
1591 if (group) {
1592 pci_dev_put(tmp);
1593 return group;
1594 }
1595 }
1596
1597 return NULL;
1598}
1599
1600/*
1601 * Look for aliases to or from the given device for existing groups. DMA
1602 * aliases are only supported on the same bus, therefore the search
1603 * space is quite small (especially since we're really only looking at pcie
1604 * device, and therefore only expect multiple slots on the root complex or
1605 * downstream switch ports). It's conceivable though that a pair of
1606 * multifunction devices could have aliases between them that would cause a
1607 * loop. To prevent this, we use a bitmap to track where we've been.
1608 */
1609static struct iommu_group *get_pci_alias_group(struct pci_dev *pdev,
1610 unsigned long *devfns)
1611{
1612 struct pci_dev *tmp = NULL;
1613 struct iommu_group *group;
1614
1615 if (test_and_set_bit(pdev->devfn & 0xff, devfns))
1616 return NULL;
1617
1618 group = iommu_group_get(&pdev->dev);
1619 if (group)
1620 return group;
1621
1622 for_each_pci_dev(tmp) {
1623 if (tmp == pdev || tmp->bus != pdev->bus)
1624 continue;
1625
1626 /* We alias them or they alias us */
1627 if (pci_devs_are_dma_aliases(pdev, tmp)) {
1628 group = get_pci_alias_group(tmp, devfns);
1629 if (group) {
1630 pci_dev_put(tmp);
1631 return group;
1632 }
1633
1634 group = get_pci_function_alias_group(tmp, devfns);
1635 if (group) {
1636 pci_dev_put(tmp);
1637 return group;
1638 }
1639 }
1640 }
1641
1642 return NULL;
1643}
1644
1645struct group_for_pci_data {
1646 struct pci_dev *pdev;
1647 struct iommu_group *group;
1648};
1649
1650/*
1651 * DMA alias iterator callback, return the last seen device. Stop and return
1652 * the IOMMU group if we find one along the way.
1653 */
1654static int get_pci_alias_or_group(struct pci_dev *pdev, u16 alias, void *opaque)
1655{
1656 struct group_for_pci_data *data = opaque;
1657
1658 data->pdev = pdev;
1659 data->group = iommu_group_get(&pdev->dev);
1660
1661 return data->group != NULL;
1662}
1663
1664/*
1665 * Generic device_group call-back function. It just allocates one
1666 * iommu-group per device.
1667 */
1668struct iommu_group *generic_device_group(struct device *dev)
1669{
1670 return iommu_group_alloc();
1671}
1672EXPORT_SYMBOL_GPL(generic_device_group);
1673
1674/*
1675 * Generic device_group call-back function. It just allocates one
1676 * iommu-group per iommu driver instance shared by every device
1677 * probed by that iommu driver.
1678 */
1679struct iommu_group *generic_single_device_group(struct device *dev)
1680{
1681 struct iommu_device *iommu = dev->iommu->iommu_dev;
1682
1683 if (!iommu->singleton_group) {
1684 struct iommu_group *group;
1685
1686 group = iommu_group_alloc();
1687 if (IS_ERR(group))
1688 return group;
1689 iommu->singleton_group = group;
1690 }
1691 return iommu_group_ref_get(iommu->singleton_group);
1692}
1693EXPORT_SYMBOL_GPL(generic_single_device_group);
1694
1695/*
1696 * Use standard PCI bus topology, isolation features, and DMA alias quirks
1697 * to find or create an IOMMU group for a device.
1698 */
1699struct iommu_group *pci_device_group(struct device *dev)
1700{
1701 struct pci_dev *pdev = to_pci_dev(dev);
1702 struct group_for_pci_data data;
1703 struct pci_bus *bus;
1704 struct iommu_group *group = NULL;
1705 u64 devfns[4] = { 0 };
1706
1707 if (WARN_ON(!dev_is_pci(dev)))
1708 return ERR_PTR(-EINVAL);
1709
1710 /*
1711 * Find the upstream DMA alias for the device. A device must not
1712 * be aliased due to topology in order to have its own IOMMU group.
1713 * If we find an alias along the way that already belongs to a
1714 * group, use it.
1715 */
1716 if (pci_for_each_dma_alias(pdev, get_pci_alias_or_group, &data))
1717 return data.group;
1718
1719 pdev = data.pdev;
1720
1721 /*
1722 * Continue upstream from the point of minimum IOMMU granularity
1723 * due to aliases to the point where devices are protected from
1724 * peer-to-peer DMA by PCI ACS. Again, if we find an existing
1725 * group, use it.
1726 */
1727 for (bus = pdev->bus; !pci_is_root_bus(bus); bus = bus->parent) {
1728 if (!bus->self)
1729 continue;
1730
1731 if (pci_acs_path_enabled(bus->self, NULL, REQ_ACS_FLAGS))
1732 break;
1733
1734 pdev = bus->self;
1735
1736 group = iommu_group_get(&pdev->dev);
1737 if (group)
1738 return group;
1739 }
1740
1741 /*
1742 * Look for existing groups on device aliases. If we alias another
1743 * device or another device aliases us, use the same group.
1744 */
1745 group = get_pci_alias_group(pdev, (unsigned long *)devfns);
1746 if (group)
1747 return group;
1748
1749 /*
1750 * Look for existing groups on non-isolated functions on the same
1751 * slot and aliases of those funcions, if any. No need to clear
1752 * the search bitmap, the tested devfns are still valid.
1753 */
1754 group = get_pci_function_alias_group(pdev, (unsigned long *)devfns);
1755 if (group)
1756 return group;
1757
1758 /* No shared group found, allocate new */
1759 return iommu_group_alloc();
1760}
1761EXPORT_SYMBOL_GPL(pci_device_group);
1762
1763/* Get the IOMMU group for device on fsl-mc bus */
1764struct iommu_group *fsl_mc_device_group(struct device *dev)
1765{
1766 struct device *cont_dev = fsl_mc_cont_dev(dev);
1767 struct iommu_group *group;
1768
1769 group = iommu_group_get(cont_dev);
1770 if (!group)
1771 group = iommu_group_alloc();
1772 return group;
1773}
1774EXPORT_SYMBOL_GPL(fsl_mc_device_group);
1775
1776static struct iommu_domain *
1777__iommu_group_alloc_default_domain(struct iommu_group *group, int req_type)
1778{
1779 if (group->default_domain && group->default_domain->type == req_type)
1780 return group->default_domain;
1781 return __iommu_group_domain_alloc(group, req_type);
1782}
1783
1784/*
1785 * req_type of 0 means "auto" which means to select a domain based on
1786 * iommu_def_domain_type or what the driver actually supports.
1787 */
1788static struct iommu_domain *
1789iommu_group_alloc_default_domain(struct iommu_group *group, int req_type)
1790{
1791 const struct iommu_ops *ops = dev_iommu_ops(iommu_group_first_dev(group));
1792 struct iommu_domain *dom;
1793
1794 lockdep_assert_held(&group->mutex);
1795
1796 /*
1797 * Allow legacy drivers to specify the domain that will be the default
1798 * domain. This should always be either an IDENTITY/BLOCKED/PLATFORM
1799 * domain. Do not use in new drivers.
1800 */
1801 if (ops->default_domain) {
1802 if (req_type != ops->default_domain->type)
1803 return ERR_PTR(-EINVAL);
1804 return ops->default_domain;
1805 }
1806
1807 if (req_type)
1808 return __iommu_group_alloc_default_domain(group, req_type);
1809
1810 /* The driver gave no guidance on what type to use, try the default */
1811 dom = __iommu_group_alloc_default_domain(group, iommu_def_domain_type);
1812 if (!IS_ERR(dom))
1813 return dom;
1814
1815 /* Otherwise IDENTITY and DMA_FQ defaults will try DMA */
1816 if (iommu_def_domain_type == IOMMU_DOMAIN_DMA)
1817 return ERR_PTR(-EINVAL);
1818 dom = __iommu_group_alloc_default_domain(group, IOMMU_DOMAIN_DMA);
1819 if (IS_ERR(dom))
1820 return dom;
1821
1822 pr_warn("Failed to allocate default IOMMU domain of type %u for group %s - Falling back to IOMMU_DOMAIN_DMA",
1823 iommu_def_domain_type, group->name);
1824 return dom;
1825}
1826
1827struct iommu_domain *iommu_group_default_domain(struct iommu_group *group)
1828{
1829 return group->default_domain;
1830}
1831
1832static int probe_iommu_group(struct device *dev, void *data)
1833{
1834 struct list_head *group_list = data;
1835 int ret;
1836
1837 mutex_lock(&iommu_probe_device_lock);
1838 ret = __iommu_probe_device(dev, group_list);
1839 mutex_unlock(&iommu_probe_device_lock);
1840 if (ret == -ENODEV)
1841 ret = 0;
1842
1843 return ret;
1844}
1845
1846static int iommu_bus_notifier(struct notifier_block *nb,
1847 unsigned long action, void *data)
1848{
1849 struct device *dev = data;
1850
1851 if (action == BUS_NOTIFY_ADD_DEVICE) {
1852 int ret;
1853
1854 ret = iommu_probe_device(dev);
1855 return (ret) ? NOTIFY_DONE : NOTIFY_OK;
1856 } else if (action == BUS_NOTIFY_REMOVED_DEVICE) {
1857 iommu_release_device(dev);
1858 return NOTIFY_OK;
1859 }
1860
1861 return 0;
1862}
1863
1864/*
1865 * Combine the driver's chosen def_domain_type across all the devices in a
1866 * group. Drivers must give a consistent result.
1867 */
1868static int iommu_get_def_domain_type(struct iommu_group *group,
1869 struct device *dev, int cur_type)
1870{
1871 const struct iommu_ops *ops = dev_iommu_ops(dev);
1872 int type;
1873
1874 if (ops->default_domain) {
1875 /*
1876 * Drivers that declare a global static default_domain will
1877 * always choose that.
1878 */
1879 type = ops->default_domain->type;
1880 } else {
1881 if (ops->def_domain_type)
1882 type = ops->def_domain_type(dev);
1883 else
1884 return cur_type;
1885 }
1886 if (!type || cur_type == type)
1887 return cur_type;
1888 if (!cur_type)
1889 return type;
1890
1891 dev_err_ratelimited(
1892 dev,
1893 "IOMMU driver error, requesting conflicting def_domain_type, %s and %s, for devices in group %u.\n",
1894 iommu_domain_type_str(cur_type), iommu_domain_type_str(type),
1895 group->id);
1896
1897 /*
1898 * Try to recover, drivers are allowed to force IDENITY or DMA, IDENTITY
1899 * takes precedence.
1900 */
1901 if (type == IOMMU_DOMAIN_IDENTITY)
1902 return type;
1903 return cur_type;
1904}
1905
1906/*
1907 * A target_type of 0 will select the best domain type. 0 can be returned in
1908 * this case meaning the global default should be used.
1909 */
1910static int iommu_get_default_domain_type(struct iommu_group *group,
1911 int target_type)
1912{
1913 struct device *untrusted = NULL;
1914 struct group_device *gdev;
1915 int driver_type = 0;
1916
1917 lockdep_assert_held(&group->mutex);
1918
1919 /*
1920 * ARM32 drivers supporting CONFIG_ARM_DMA_USE_IOMMU can declare an
1921 * identity_domain and it will automatically become their default
1922 * domain. Later on ARM_DMA_USE_IOMMU will install its UNMANAGED domain.
1923 * Override the selection to IDENTITY.
1924 */
1925 if (IS_ENABLED(CONFIG_ARM_DMA_USE_IOMMU)) {
1926 static_assert(!(IS_ENABLED(CONFIG_ARM_DMA_USE_IOMMU) &&
1927 IS_ENABLED(CONFIG_IOMMU_DMA)));
1928 driver_type = IOMMU_DOMAIN_IDENTITY;
1929 }
1930
1931 for_each_group_device(group, gdev) {
1932 driver_type = iommu_get_def_domain_type(group, gdev->dev,
1933 driver_type);
1934
1935 if (dev_is_pci(gdev->dev) && to_pci_dev(gdev->dev)->untrusted) {
1936 /*
1937 * No ARM32 using systems will set untrusted, it cannot
1938 * work.
1939 */
1940 if (WARN_ON(IS_ENABLED(CONFIG_ARM_DMA_USE_IOMMU)))
1941 return -1;
1942 untrusted = gdev->dev;
1943 }
1944 }
1945
1946 /*
1947 * If the common dma ops are not selected in kconfig then we cannot use
1948 * IOMMU_DOMAIN_DMA at all. Force IDENTITY if nothing else has been
1949 * selected.
1950 */
1951 if (!IS_ENABLED(CONFIG_IOMMU_DMA)) {
1952 if (WARN_ON(driver_type == IOMMU_DOMAIN_DMA))
1953 return -1;
1954 if (!driver_type)
1955 driver_type = IOMMU_DOMAIN_IDENTITY;
1956 }
1957
1958 if (untrusted) {
1959 if (driver_type && driver_type != IOMMU_DOMAIN_DMA) {
1960 dev_err_ratelimited(
1961 untrusted,
1962 "Device is not trusted, but driver is overriding group %u to %s, refusing to probe.\n",
1963 group->id, iommu_domain_type_str(driver_type));
1964 return -1;
1965 }
1966 driver_type = IOMMU_DOMAIN_DMA;
1967 }
1968
1969 if (target_type) {
1970 if (driver_type && target_type != driver_type)
1971 return -1;
1972 return target_type;
1973 }
1974 return driver_type;
1975}
1976
1977static void iommu_group_do_probe_finalize(struct device *dev)
1978{
1979 const struct iommu_ops *ops = dev_iommu_ops(dev);
1980
1981 if (ops->probe_finalize)
1982 ops->probe_finalize(dev);
1983}
1984
1985int bus_iommu_probe(const struct bus_type *bus)
1986{
1987 struct iommu_group *group, *next;
1988 LIST_HEAD(group_list);
1989 int ret;
1990
1991 ret = bus_for_each_dev(bus, NULL, &group_list, probe_iommu_group);
1992 if (ret)
1993 return ret;
1994
1995 list_for_each_entry_safe(group, next, &group_list, entry) {
1996 struct group_device *gdev;
1997
1998 mutex_lock(&group->mutex);
1999
2000 /* Remove item from the list */
2001 list_del_init(&group->entry);
2002
2003 /*
2004 * We go to the trouble of deferred default domain creation so
2005 * that the cross-group default domain type and the setup of the
2006 * IOMMU_RESV_DIRECT will work correctly in non-hotpug scenarios.
2007 */
2008 ret = iommu_setup_default_domain(group, 0);
2009 if (ret) {
2010 mutex_unlock(&group->mutex);
2011 return ret;
2012 }
2013 mutex_unlock(&group->mutex);
2014
2015 /*
2016 * FIXME: Mis-locked because the ops->probe_finalize() call-back
2017 * of some IOMMU drivers calls arm_iommu_attach_device() which
2018 * in-turn might call back into IOMMU core code, where it tries
2019 * to take group->mutex, resulting in a deadlock.
2020 */
2021 for_each_group_device(group, gdev)
2022 iommu_group_do_probe_finalize(gdev->dev);
2023 }
2024
2025 return 0;
2026}
2027
2028/**
2029 * iommu_present() - make platform-specific assumptions about an IOMMU
2030 * @bus: bus to check
2031 *
2032 * Do not use this function. You want device_iommu_mapped() instead.
2033 *
2034 * Return: true if some IOMMU is present and aware of devices on the given bus;
2035 * in general it may not be the only IOMMU, and it may not have anything to do
2036 * with whatever device you are ultimately interested in.
2037 */
2038bool iommu_present(const struct bus_type *bus)
2039{
2040 bool ret = false;
2041
2042 for (int i = 0; i < ARRAY_SIZE(iommu_buses); i++) {
2043 if (iommu_buses[i] == bus) {
2044 spin_lock(&iommu_device_lock);
2045 ret = !list_empty(&iommu_device_list);
2046 spin_unlock(&iommu_device_lock);
2047 }
2048 }
2049 return ret;
2050}
2051EXPORT_SYMBOL_GPL(iommu_present);
2052
2053/**
2054 * device_iommu_capable() - check for a general IOMMU capability
2055 * @dev: device to which the capability would be relevant, if available
2056 * @cap: IOMMU capability
2057 *
2058 * Return: true if an IOMMU is present and supports the given capability
2059 * for the given device, otherwise false.
2060 */
2061bool device_iommu_capable(struct device *dev, enum iommu_cap cap)
2062{
2063 const struct iommu_ops *ops;
2064
2065 if (!dev_has_iommu(dev))
2066 return false;
2067
2068 ops = dev_iommu_ops(dev);
2069 if (!ops->capable)
2070 return false;
2071
2072 return ops->capable(dev, cap);
2073}
2074EXPORT_SYMBOL_GPL(device_iommu_capable);
2075
2076/**
2077 * iommu_group_has_isolated_msi() - Compute msi_device_has_isolated_msi()
2078 * for a group
2079 * @group: Group to query
2080 *
2081 * IOMMU groups should not have differing values of
2082 * msi_device_has_isolated_msi() for devices in a group. However nothing
2083 * directly prevents this, so ensure mistakes don't result in isolation failures
2084 * by checking that all the devices are the same.
2085 */
2086bool iommu_group_has_isolated_msi(struct iommu_group *group)
2087{
2088 struct group_device *group_dev;
2089 bool ret = true;
2090
2091 mutex_lock(&group->mutex);
2092 for_each_group_device(group, group_dev)
2093 ret &= msi_device_has_isolated_msi(group_dev->dev);
2094 mutex_unlock(&group->mutex);
2095 return ret;
2096}
2097EXPORT_SYMBOL_GPL(iommu_group_has_isolated_msi);
2098
2099/**
2100 * iommu_set_fault_handler() - set a fault handler for an iommu domain
2101 * @domain: iommu domain
2102 * @handler: fault handler
2103 * @token: user data, will be passed back to the fault handler
2104 *
2105 * This function should be used by IOMMU users which want to be notified
2106 * whenever an IOMMU fault happens.
2107 *
2108 * The fault handler itself should return 0 on success, and an appropriate
2109 * error code otherwise.
2110 */
2111void iommu_set_fault_handler(struct iommu_domain *domain,
2112 iommu_fault_handler_t handler,
2113 void *token)
2114{
2115 BUG_ON(!domain);
2116
2117 domain->handler = handler;
2118 domain->handler_token = token;
2119}
2120EXPORT_SYMBOL_GPL(iommu_set_fault_handler);
2121
2122static struct iommu_domain *__iommu_domain_alloc(const struct iommu_ops *ops,
2123 struct device *dev,
2124 unsigned int type)
2125{
2126 struct iommu_domain *domain;
2127 unsigned int alloc_type = type & IOMMU_DOMAIN_ALLOC_FLAGS;
2128
2129 if (alloc_type == IOMMU_DOMAIN_IDENTITY && ops->identity_domain)
2130 return ops->identity_domain;
2131 else if (alloc_type == IOMMU_DOMAIN_BLOCKED && ops->blocked_domain)
2132 return ops->blocked_domain;
2133 else if (type & __IOMMU_DOMAIN_PAGING && ops->domain_alloc_paging)
2134 domain = ops->domain_alloc_paging(dev);
2135 else if (ops->domain_alloc)
2136 domain = ops->domain_alloc(alloc_type);
2137 else
2138 return ERR_PTR(-EOPNOTSUPP);
2139
2140 /*
2141 * Many domain_alloc ops now return ERR_PTR, make things easier for the
2142 * driver by accepting ERR_PTR from all domain_alloc ops instead of
2143 * having two rules.
2144 */
2145 if (IS_ERR(domain))
2146 return domain;
2147 if (!domain)
2148 return ERR_PTR(-ENOMEM);
2149
2150 domain->type = type;
2151 domain->owner = ops;
2152 /*
2153 * If not already set, assume all sizes by default; the driver
2154 * may override this later
2155 */
2156 if (!domain->pgsize_bitmap)
2157 domain->pgsize_bitmap = ops->pgsize_bitmap;
2158
2159 if (!domain->ops)
2160 domain->ops = ops->default_domain_ops;
2161
2162 if (iommu_is_dma_domain(domain)) {
2163 int rc;
2164
2165 rc = iommu_get_dma_cookie(domain);
2166 if (rc) {
2167 iommu_domain_free(domain);
2168 return ERR_PTR(rc);
2169 }
2170 }
2171 return domain;
2172}
2173
2174static struct iommu_domain *
2175__iommu_group_domain_alloc(struct iommu_group *group, unsigned int type)
2176{
2177 struct device *dev = iommu_group_first_dev(group);
2178
2179 return __iommu_domain_alloc(dev_iommu_ops(dev), dev, type);
2180}
2181
2182static int __iommu_domain_alloc_dev(struct device *dev, void *data)
2183{
2184 const struct iommu_ops **ops = data;
2185
2186 if (!dev_has_iommu(dev))
2187 return 0;
2188
2189 if (WARN_ONCE(*ops && *ops != dev_iommu_ops(dev),
2190 "Multiple IOMMU drivers present for bus %s, which the public IOMMU API can't fully support yet. You will still need to disable one or more for this to work, sorry!\n",
2191 dev_bus_name(dev)))
2192 return -EBUSY;
2193
2194 *ops = dev_iommu_ops(dev);
2195 return 0;
2196}
2197
2198struct iommu_domain *iommu_domain_alloc(const struct bus_type *bus)
2199{
2200 const struct iommu_ops *ops = NULL;
2201 int err = bus_for_each_dev(bus, NULL, &ops, __iommu_domain_alloc_dev);
2202 struct iommu_domain *domain;
2203
2204 if (err || !ops)
2205 return NULL;
2206
2207 domain = __iommu_domain_alloc(ops, NULL, IOMMU_DOMAIN_UNMANAGED);
2208 if (IS_ERR(domain))
2209 return NULL;
2210 return domain;
2211}
2212EXPORT_SYMBOL_GPL(iommu_domain_alloc);
2213
2214void iommu_domain_free(struct iommu_domain *domain)
2215{
2216 if (domain->type == IOMMU_DOMAIN_SVA)
2217 mmdrop(domain->mm);
2218 iommu_put_dma_cookie(domain);
2219 if (domain->ops->free)
2220 domain->ops->free(domain);
2221}
2222EXPORT_SYMBOL_GPL(iommu_domain_free);
2223
2224/*
2225 * Put the group's domain back to the appropriate core-owned domain - either the
2226 * standard kernel-mode DMA configuration or an all-DMA-blocked domain.
2227 */
2228static void __iommu_group_set_core_domain(struct iommu_group *group)
2229{
2230 struct iommu_domain *new_domain;
2231
2232 if (group->owner)
2233 new_domain = group->blocking_domain;
2234 else
2235 new_domain = group->default_domain;
2236
2237 __iommu_group_set_domain_nofail(group, new_domain);
2238}
2239
2240static int __iommu_attach_device(struct iommu_domain *domain,
2241 struct device *dev)
2242{
2243 int ret;
2244
2245 if (unlikely(domain->ops->attach_dev == NULL))
2246 return -ENODEV;
2247
2248 ret = domain->ops->attach_dev(domain, dev);
2249 if (ret)
2250 return ret;
2251 dev->iommu->attach_deferred = 0;
2252 trace_attach_device_to_domain(dev);
2253 return 0;
2254}
2255
2256/**
2257 * iommu_attach_device - Attach an IOMMU domain to a device
2258 * @domain: IOMMU domain to attach
2259 * @dev: Device that will be attached
2260 *
2261 * Returns 0 on success and error code on failure
2262 *
2263 * Note that EINVAL can be treated as a soft failure, indicating
2264 * that certain configuration of the domain is incompatible with
2265 * the device. In this case attaching a different domain to the
2266 * device may succeed.
2267 */
2268int iommu_attach_device(struct iommu_domain *domain, struct device *dev)
2269{
2270 /* Caller must be a probed driver on dev */
2271 struct iommu_group *group = dev->iommu_group;
2272 int ret;
2273
2274 if (!group)
2275 return -ENODEV;
2276
2277 /*
2278 * Lock the group to make sure the device-count doesn't
2279 * change while we are attaching
2280 */
2281 mutex_lock(&group->mutex);
2282 ret = -EINVAL;
2283 if (list_count_nodes(&group->devices) != 1)
2284 goto out_unlock;
2285
2286 ret = __iommu_attach_group(domain, group);
2287
2288out_unlock:
2289 mutex_unlock(&group->mutex);
2290 return ret;
2291}
2292EXPORT_SYMBOL_GPL(iommu_attach_device);
2293
2294int iommu_deferred_attach(struct device *dev, struct iommu_domain *domain)
2295{
2296 if (dev->iommu && dev->iommu->attach_deferred)
2297 return __iommu_attach_device(domain, dev);
2298
2299 return 0;
2300}
2301
2302void iommu_detach_device(struct iommu_domain *domain, struct device *dev)
2303{
2304 /* Caller must be a probed driver on dev */
2305 struct iommu_group *group = dev->iommu_group;
2306
2307 if (!group)
2308 return;
2309
2310 mutex_lock(&group->mutex);
2311 if (WARN_ON(domain != group->domain) ||
2312 WARN_ON(list_count_nodes(&group->devices) != 1))
2313 goto out_unlock;
2314 __iommu_group_set_core_domain(group);
2315
2316out_unlock:
2317 mutex_unlock(&group->mutex);
2318}
2319EXPORT_SYMBOL_GPL(iommu_detach_device);
2320
2321struct iommu_domain *iommu_get_domain_for_dev(struct device *dev)
2322{
2323 /* Caller must be a probed driver on dev */
2324 struct iommu_group *group = dev->iommu_group;
2325
2326 if (!group)
2327 return NULL;
2328
2329 return group->domain;
2330}
2331EXPORT_SYMBOL_GPL(iommu_get_domain_for_dev);
2332
2333/*
2334 * For IOMMU_DOMAIN_DMA implementations which already provide their own
2335 * guarantees that the group and its default domain are valid and correct.
2336 */
2337struct iommu_domain *iommu_get_dma_domain(struct device *dev)
2338{
2339 return dev->iommu_group->default_domain;
2340}
2341
2342static int __iommu_attach_group(struct iommu_domain *domain,
2343 struct iommu_group *group)
2344{
2345 struct device *dev;
2346
2347 if (group->domain && group->domain != group->default_domain &&
2348 group->domain != group->blocking_domain)
2349 return -EBUSY;
2350
2351 dev = iommu_group_first_dev(group);
2352 if (!dev_has_iommu(dev) || dev_iommu_ops(dev) != domain->owner)
2353 return -EINVAL;
2354
2355 return __iommu_group_set_domain(group, domain);
2356}
2357
2358/**
2359 * iommu_attach_group - Attach an IOMMU domain to an IOMMU group
2360 * @domain: IOMMU domain to attach
2361 * @group: IOMMU group that will be attached
2362 *
2363 * Returns 0 on success and error code on failure
2364 *
2365 * Note that EINVAL can be treated as a soft failure, indicating
2366 * that certain configuration of the domain is incompatible with
2367 * the group. In this case attaching a different domain to the
2368 * group may succeed.
2369 */
2370int iommu_attach_group(struct iommu_domain *domain, struct iommu_group *group)
2371{
2372 int ret;
2373
2374 mutex_lock(&group->mutex);
2375 ret = __iommu_attach_group(domain, group);
2376 mutex_unlock(&group->mutex);
2377
2378 return ret;
2379}
2380EXPORT_SYMBOL_GPL(iommu_attach_group);
2381
2382/**
2383 * iommu_group_replace_domain - replace the domain that a group is attached to
2384 * @new_domain: new IOMMU domain to replace with
2385 * @group: IOMMU group that will be attached to the new domain
2386 *
2387 * This API allows the group to switch domains without being forced to go to
2388 * the blocking domain in-between.
2389 *
2390 * If the currently attached domain is a core domain (e.g. a default_domain),
2391 * it will act just like the iommu_attach_group().
2392 */
2393int iommu_group_replace_domain(struct iommu_group *group,
2394 struct iommu_domain *new_domain)
2395{
2396 int ret;
2397
2398 if (!new_domain)
2399 return -EINVAL;
2400
2401 mutex_lock(&group->mutex);
2402 ret = __iommu_group_set_domain(group, new_domain);
2403 mutex_unlock(&group->mutex);
2404 return ret;
2405}
2406EXPORT_SYMBOL_NS_GPL(iommu_group_replace_domain, IOMMUFD_INTERNAL);
2407
2408static int __iommu_device_set_domain(struct iommu_group *group,
2409 struct device *dev,
2410 struct iommu_domain *new_domain,
2411 unsigned int flags)
2412{
2413 int ret;
2414
2415 /*
2416 * If the device requires IOMMU_RESV_DIRECT then we cannot allow
2417 * the blocking domain to be attached as it does not contain the
2418 * required 1:1 mapping. This test effectively excludes the device
2419 * being used with iommu_group_claim_dma_owner() which will block
2420 * vfio and iommufd as well.
2421 */
2422 if (dev->iommu->require_direct &&
2423 (new_domain->type == IOMMU_DOMAIN_BLOCKED ||
2424 new_domain == group->blocking_domain)) {
2425 dev_warn(dev,
2426 "Firmware has requested this device have a 1:1 IOMMU mapping, rejecting configuring the device without a 1:1 mapping. Contact your platform vendor.\n");
2427 return -EINVAL;
2428 }
2429
2430 if (dev->iommu->attach_deferred) {
2431 if (new_domain == group->default_domain)
2432 return 0;
2433 dev->iommu->attach_deferred = 0;
2434 }
2435
2436 ret = __iommu_attach_device(new_domain, dev);
2437 if (ret) {
2438 /*
2439 * If we have a blocking domain then try to attach that in hopes
2440 * of avoiding a UAF. Modern drivers should implement blocking
2441 * domains as global statics that cannot fail.
2442 */
2443 if ((flags & IOMMU_SET_DOMAIN_MUST_SUCCEED) &&
2444 group->blocking_domain &&
2445 group->blocking_domain != new_domain)
2446 __iommu_attach_device(group->blocking_domain, dev);
2447 return ret;
2448 }
2449 return 0;
2450}
2451
2452/*
2453 * If 0 is returned the group's domain is new_domain. If an error is returned
2454 * then the group's domain will be set back to the existing domain unless
2455 * IOMMU_SET_DOMAIN_MUST_SUCCEED, otherwise an error is returned and the group's
2456 * domains is left inconsistent. This is a driver bug to fail attach with a
2457 * previously good domain. We try to avoid a kernel UAF because of this.
2458 *
2459 * IOMMU groups are really the natural working unit of the IOMMU, but the IOMMU
2460 * API works on domains and devices. Bridge that gap by iterating over the
2461 * devices in a group. Ideally we'd have a single device which represents the
2462 * requestor ID of the group, but we also allow IOMMU drivers to create policy
2463 * defined minimum sets, where the physical hardware may be able to distiguish
2464 * members, but we wish to group them at a higher level (ex. untrusted
2465 * multi-function PCI devices). Thus we attach each device.
2466 */
2467static int __iommu_group_set_domain_internal(struct iommu_group *group,
2468 struct iommu_domain *new_domain,
2469 unsigned int flags)
2470{
2471 struct group_device *last_gdev;
2472 struct group_device *gdev;
2473 int result;
2474 int ret;
2475
2476 lockdep_assert_held(&group->mutex);
2477
2478 if (group->domain == new_domain)
2479 return 0;
2480
2481 if (WARN_ON(!new_domain))
2482 return -EINVAL;
2483
2484 /*
2485 * Changing the domain is done by calling attach_dev() on the new
2486 * domain. This switch does not have to be atomic and DMA can be
2487 * discarded during the transition. DMA must only be able to access
2488 * either new_domain or group->domain, never something else.
2489 */
2490 result = 0;
2491 for_each_group_device(group, gdev) {
2492 ret = __iommu_device_set_domain(group, gdev->dev, new_domain,
2493 flags);
2494 if (ret) {
2495 result = ret;
2496 /*
2497 * Keep trying the other devices in the group. If a
2498 * driver fails attach to an otherwise good domain, and
2499 * does not support blocking domains, it should at least
2500 * drop its reference on the current domain so we don't
2501 * UAF.
2502 */
2503 if (flags & IOMMU_SET_DOMAIN_MUST_SUCCEED)
2504 continue;
2505 goto err_revert;
2506 }
2507 }
2508 group->domain = new_domain;
2509 return result;
2510
2511err_revert:
2512 /*
2513 * This is called in error unwind paths. A well behaved driver should
2514 * always allow us to attach to a domain that was already attached.
2515 */
2516 last_gdev = gdev;
2517 for_each_group_device(group, gdev) {
2518 /*
2519 * A NULL domain can happen only for first probe, in which case
2520 * we leave group->domain as NULL and let release clean
2521 * everything up.
2522 */
2523 if (group->domain)
2524 WARN_ON(__iommu_device_set_domain(
2525 group, gdev->dev, group->domain,
2526 IOMMU_SET_DOMAIN_MUST_SUCCEED));
2527 if (gdev == last_gdev)
2528 break;
2529 }
2530 return ret;
2531}
2532
2533void iommu_detach_group(struct iommu_domain *domain, struct iommu_group *group)
2534{
2535 mutex_lock(&group->mutex);
2536 __iommu_group_set_core_domain(group);
2537 mutex_unlock(&group->mutex);
2538}
2539EXPORT_SYMBOL_GPL(iommu_detach_group);
2540
2541phys_addr_t iommu_iova_to_phys(struct iommu_domain *domain, dma_addr_t iova)
2542{
2543 if (domain->type == IOMMU_DOMAIN_IDENTITY)
2544 return iova;
2545
2546 if (domain->type == IOMMU_DOMAIN_BLOCKED)
2547 return 0;
2548
2549 return domain->ops->iova_to_phys(domain, iova);
2550}
2551EXPORT_SYMBOL_GPL(iommu_iova_to_phys);
2552
2553static size_t iommu_pgsize(struct iommu_domain *domain, unsigned long iova,
2554 phys_addr_t paddr, size_t size, size_t *count)
2555{
2556 unsigned int pgsize_idx, pgsize_idx_next;
2557 unsigned long pgsizes;
2558 size_t offset, pgsize, pgsize_next;
2559 unsigned long addr_merge = paddr | iova;
2560
2561 /* Page sizes supported by the hardware and small enough for @size */
2562 pgsizes = domain->pgsize_bitmap & GENMASK(__fls(size), 0);
2563
2564 /* Constrain the page sizes further based on the maximum alignment */
2565 if (likely(addr_merge))
2566 pgsizes &= GENMASK(__ffs(addr_merge), 0);
2567
2568 /* Make sure we have at least one suitable page size */
2569 BUG_ON(!pgsizes);
2570
2571 /* Pick the biggest page size remaining */
2572 pgsize_idx = __fls(pgsizes);
2573 pgsize = BIT(pgsize_idx);
2574 if (!count)
2575 return pgsize;
2576
2577 /* Find the next biggest support page size, if it exists */
2578 pgsizes = domain->pgsize_bitmap & ~GENMASK(pgsize_idx, 0);
2579 if (!pgsizes)
2580 goto out_set_count;
2581
2582 pgsize_idx_next = __ffs(pgsizes);
2583 pgsize_next = BIT(pgsize_idx_next);
2584
2585 /*
2586 * There's no point trying a bigger page size unless the virtual
2587 * and physical addresses are similarly offset within the larger page.
2588 */
2589 if ((iova ^ paddr) & (pgsize_next - 1))
2590 goto out_set_count;
2591
2592 /* Calculate the offset to the next page size alignment boundary */
2593 offset = pgsize_next - (addr_merge & (pgsize_next - 1));
2594
2595 /*
2596 * If size is big enough to accommodate the larger page, reduce
2597 * the number of smaller pages.
2598 */
2599 if (offset + pgsize_next <= size)
2600 size = offset;
2601
2602out_set_count:
2603 *count = size >> pgsize_idx;
2604 return pgsize;
2605}
2606
2607static int __iommu_map(struct iommu_domain *domain, unsigned long iova,
2608 phys_addr_t paddr, size_t size, int prot, gfp_t gfp)
2609{
2610 const struct iommu_domain_ops *ops = domain->ops;
2611 unsigned long orig_iova = iova;
2612 unsigned int min_pagesz;
2613 size_t orig_size = size;
2614 phys_addr_t orig_paddr = paddr;
2615 int ret = 0;
2616
2617 if (unlikely(!(domain->type & __IOMMU_DOMAIN_PAGING)))
2618 return -EINVAL;
2619
2620 if (WARN_ON(!ops->map_pages || domain->pgsize_bitmap == 0UL))
2621 return -ENODEV;
2622
2623 /* find out the minimum page size supported */
2624 min_pagesz = 1 << __ffs(domain->pgsize_bitmap);
2625
2626 /*
2627 * both the virtual address and the physical one, as well as
2628 * the size of the mapping, must be aligned (at least) to the
2629 * size of the smallest page supported by the hardware
2630 */
2631 if (!IS_ALIGNED(iova | paddr | size, min_pagesz)) {
2632 pr_err("unaligned: iova 0x%lx pa %pa size 0x%zx min_pagesz 0x%x\n",
2633 iova, &paddr, size, min_pagesz);
2634 return -EINVAL;
2635 }
2636
2637 pr_debug("map: iova 0x%lx pa %pa size 0x%zx\n", iova, &paddr, size);
2638
2639 while (size) {
2640 size_t pgsize, count, mapped = 0;
2641
2642 pgsize = iommu_pgsize(domain, iova, paddr, size, &count);
2643
2644 pr_debug("mapping: iova 0x%lx pa %pa pgsize 0x%zx count %zu\n",
2645 iova, &paddr, pgsize, count);
2646 ret = ops->map_pages(domain, iova, paddr, pgsize, count, prot,
2647 gfp, &mapped);
2648 /*
2649 * Some pages may have been mapped, even if an error occurred,
2650 * so we should account for those so they can be unmapped.
2651 */
2652 size -= mapped;
2653
2654 if (ret)
2655 break;
2656
2657 iova += mapped;
2658 paddr += mapped;
2659 }
2660
2661 /* unroll mapping in case something went wrong */
2662 if (ret)
2663 iommu_unmap(domain, orig_iova, orig_size - size);
2664 else
2665 trace_map(orig_iova, orig_paddr, orig_size);
2666
2667 return ret;
2668}
2669
2670int iommu_map(struct iommu_domain *domain, unsigned long iova,
2671 phys_addr_t paddr, size_t size, int prot, gfp_t gfp)
2672{
2673 const struct iommu_domain_ops *ops = domain->ops;
2674 int ret;
2675
2676 might_sleep_if(gfpflags_allow_blocking(gfp));
2677
2678 /* Discourage passing strange GFP flags */
2679 if (WARN_ON_ONCE(gfp & (__GFP_COMP | __GFP_DMA | __GFP_DMA32 |
2680 __GFP_HIGHMEM)))
2681 return -EINVAL;
2682
2683 ret = __iommu_map(domain, iova, paddr, size, prot, gfp);
2684 if (ret == 0 && ops->iotlb_sync_map) {
2685 ret = ops->iotlb_sync_map(domain, iova, size);
2686 if (ret)
2687 goto out_err;
2688 }
2689
2690 return ret;
2691
2692out_err:
2693 /* undo mappings already done */
2694 iommu_unmap(domain, iova, size);
2695
2696 return ret;
2697}
2698EXPORT_SYMBOL_GPL(iommu_map);
2699
2700static size_t __iommu_unmap(struct iommu_domain *domain,
2701 unsigned long iova, size_t size,
2702 struct iommu_iotlb_gather *iotlb_gather)
2703{
2704 const struct iommu_domain_ops *ops = domain->ops;
2705 size_t unmapped_page, unmapped = 0;
2706 unsigned long orig_iova = iova;
2707 unsigned int min_pagesz;
2708
2709 if (unlikely(!(domain->type & __IOMMU_DOMAIN_PAGING)))
2710 return 0;
2711
2712 if (WARN_ON(!ops->unmap_pages || domain->pgsize_bitmap == 0UL))
2713 return 0;
2714
2715 /* find out the minimum page size supported */
2716 min_pagesz = 1 << __ffs(domain->pgsize_bitmap);
2717
2718 /*
2719 * The virtual address, as well as the size of the mapping, must be
2720 * aligned (at least) to the size of the smallest page supported
2721 * by the hardware
2722 */
2723 if (!IS_ALIGNED(iova | size, min_pagesz)) {
2724 pr_err("unaligned: iova 0x%lx size 0x%zx min_pagesz 0x%x\n",
2725 iova, size, min_pagesz);
2726 return 0;
2727 }
2728
2729 pr_debug("unmap this: iova 0x%lx size 0x%zx\n", iova, size);
2730
2731 /*
2732 * Keep iterating until we either unmap 'size' bytes (or more)
2733 * or we hit an area that isn't mapped.
2734 */
2735 while (unmapped < size) {
2736 size_t pgsize, count;
2737
2738 pgsize = iommu_pgsize(domain, iova, iova, size - unmapped, &count);
2739 unmapped_page = ops->unmap_pages(domain, iova, pgsize, count, iotlb_gather);
2740 if (!unmapped_page)
2741 break;
2742
2743 pr_debug("unmapped: iova 0x%lx size 0x%zx\n",
2744 iova, unmapped_page);
2745
2746 iova += unmapped_page;
2747 unmapped += unmapped_page;
2748 }
2749
2750 trace_unmap(orig_iova, size, unmapped);
2751 return unmapped;
2752}
2753
2754size_t iommu_unmap(struct iommu_domain *domain,
2755 unsigned long iova, size_t size)
2756{
2757 struct iommu_iotlb_gather iotlb_gather;
2758 size_t ret;
2759
2760 iommu_iotlb_gather_init(&iotlb_gather);
2761 ret = __iommu_unmap(domain, iova, size, &iotlb_gather);
2762 iommu_iotlb_sync(domain, &iotlb_gather);
2763
2764 return ret;
2765}
2766EXPORT_SYMBOL_GPL(iommu_unmap);
2767
2768size_t iommu_unmap_fast(struct iommu_domain *domain,
2769 unsigned long iova, size_t size,
2770 struct iommu_iotlb_gather *iotlb_gather)
2771{
2772 return __iommu_unmap(domain, iova, size, iotlb_gather);
2773}
2774EXPORT_SYMBOL_GPL(iommu_unmap_fast);
2775
2776ssize_t iommu_map_sg(struct iommu_domain *domain, unsigned long iova,
2777 struct scatterlist *sg, unsigned int nents, int prot,
2778 gfp_t gfp)
2779{
2780 const struct iommu_domain_ops *ops = domain->ops;
2781 size_t len = 0, mapped = 0;
2782 phys_addr_t start;
2783 unsigned int i = 0;
2784 int ret;
2785
2786 might_sleep_if(gfpflags_allow_blocking(gfp));
2787
2788 /* Discourage passing strange GFP flags */
2789 if (WARN_ON_ONCE(gfp & (__GFP_COMP | __GFP_DMA | __GFP_DMA32 |
2790 __GFP_HIGHMEM)))
2791 return -EINVAL;
2792
2793 while (i <= nents) {
2794 phys_addr_t s_phys = sg_phys(sg);
2795
2796 if (len && s_phys != start + len) {
2797 ret = __iommu_map(domain, iova + mapped, start,
2798 len, prot, gfp);
2799
2800 if (ret)
2801 goto out_err;
2802
2803 mapped += len;
2804 len = 0;
2805 }
2806
2807 if (sg_dma_is_bus_address(sg))
2808 goto next;
2809
2810 if (len) {
2811 len += sg->length;
2812 } else {
2813 len = sg->length;
2814 start = s_phys;
2815 }
2816
2817next:
2818 if (++i < nents)
2819 sg = sg_next(sg);
2820 }
2821
2822 if (ops->iotlb_sync_map) {
2823 ret = ops->iotlb_sync_map(domain, iova, mapped);
2824 if (ret)
2825 goto out_err;
2826 }
2827 return mapped;
2828
2829out_err:
2830 /* undo mappings already done */
2831 iommu_unmap(domain, iova, mapped);
2832
2833 return ret;
2834}
2835EXPORT_SYMBOL_GPL(iommu_map_sg);
2836
2837/**
2838 * report_iommu_fault() - report about an IOMMU fault to the IOMMU framework
2839 * @domain: the iommu domain where the fault has happened
2840 * @dev: the device where the fault has happened
2841 * @iova: the faulting address
2842 * @flags: mmu fault flags (e.g. IOMMU_FAULT_READ/IOMMU_FAULT_WRITE/...)
2843 *
2844 * This function should be called by the low-level IOMMU implementations
2845 * whenever IOMMU faults happen, to allow high-level users, that are
2846 * interested in such events, to know about them.
2847 *
2848 * This event may be useful for several possible use cases:
2849 * - mere logging of the event
2850 * - dynamic TLB/PTE loading
2851 * - if restarting of the faulting device is required
2852 *
2853 * Returns 0 on success and an appropriate error code otherwise (if dynamic
2854 * PTE/TLB loading will one day be supported, implementations will be able
2855 * to tell whether it succeeded or not according to this return value).
2856 *
2857 * Specifically, -ENOSYS is returned if a fault handler isn't installed
2858 * (though fault handlers can also return -ENOSYS, in case they want to
2859 * elicit the default behavior of the IOMMU drivers).
2860 */
2861int report_iommu_fault(struct iommu_domain *domain, struct device *dev,
2862 unsigned long iova, int flags)
2863{
2864 int ret = -ENOSYS;
2865
2866 /*
2867 * if upper layers showed interest and installed a fault handler,
2868 * invoke it.
2869 */
2870 if (domain->handler)
2871 ret = domain->handler(domain, dev, iova, flags,
2872 domain->handler_token);
2873
2874 trace_io_page_fault(dev, iova, flags);
2875 return ret;
2876}
2877EXPORT_SYMBOL_GPL(report_iommu_fault);
2878
2879static int __init iommu_init(void)
2880{
2881 iommu_group_kset = kset_create_and_add("iommu_groups",
2882 NULL, kernel_kobj);
2883 BUG_ON(!iommu_group_kset);
2884
2885 iommu_debugfs_setup();
2886
2887 return 0;
2888}
2889core_initcall(iommu_init);
2890
2891int iommu_enable_nesting(struct iommu_domain *domain)
2892{
2893 if (domain->type != IOMMU_DOMAIN_UNMANAGED)
2894 return -EINVAL;
2895 if (!domain->ops->enable_nesting)
2896 return -EINVAL;
2897 return domain->ops->enable_nesting(domain);
2898}
2899EXPORT_SYMBOL_GPL(iommu_enable_nesting);
2900
2901int iommu_set_pgtable_quirks(struct iommu_domain *domain,
2902 unsigned long quirk)
2903{
2904 if (domain->type != IOMMU_DOMAIN_UNMANAGED)
2905 return -EINVAL;
2906 if (!domain->ops->set_pgtable_quirks)
2907 return -EINVAL;
2908 return domain->ops->set_pgtable_quirks(domain, quirk);
2909}
2910EXPORT_SYMBOL_GPL(iommu_set_pgtable_quirks);
2911
2912/**
2913 * iommu_get_resv_regions - get reserved regions
2914 * @dev: device for which to get reserved regions
2915 * @list: reserved region list for device
2916 *
2917 * This returns a list of reserved IOVA regions specific to this device.
2918 * A domain user should not map IOVA in these ranges.
2919 */
2920void iommu_get_resv_regions(struct device *dev, struct list_head *list)
2921{
2922 const struct iommu_ops *ops = dev_iommu_ops(dev);
2923
2924 if (ops->get_resv_regions)
2925 ops->get_resv_regions(dev, list);
2926}
2927EXPORT_SYMBOL_GPL(iommu_get_resv_regions);
2928
2929/**
2930 * iommu_put_resv_regions - release reserved regions
2931 * @dev: device for which to free reserved regions
2932 * @list: reserved region list for device
2933 *
2934 * This releases a reserved region list acquired by iommu_get_resv_regions().
2935 */
2936void iommu_put_resv_regions(struct device *dev, struct list_head *list)
2937{
2938 struct iommu_resv_region *entry, *next;
2939
2940 list_for_each_entry_safe(entry, next, list, list) {
2941 if (entry->free)
2942 entry->free(dev, entry);
2943 else
2944 kfree(entry);
2945 }
2946}
2947EXPORT_SYMBOL(iommu_put_resv_regions);
2948
2949struct iommu_resv_region *iommu_alloc_resv_region(phys_addr_t start,
2950 size_t length, int prot,
2951 enum iommu_resv_type type,
2952 gfp_t gfp)
2953{
2954 struct iommu_resv_region *region;
2955
2956 region = kzalloc(sizeof(*region), gfp);
2957 if (!region)
2958 return NULL;
2959
2960 INIT_LIST_HEAD(®ion->list);
2961 region->start = start;
2962 region->length = length;
2963 region->prot = prot;
2964 region->type = type;
2965 return region;
2966}
2967EXPORT_SYMBOL_GPL(iommu_alloc_resv_region);
2968
2969void iommu_set_default_passthrough(bool cmd_line)
2970{
2971 if (cmd_line)
2972 iommu_cmd_line |= IOMMU_CMD_LINE_DMA_API;
2973 iommu_def_domain_type = IOMMU_DOMAIN_IDENTITY;
2974}
2975
2976void iommu_set_default_translated(bool cmd_line)
2977{
2978 if (cmd_line)
2979 iommu_cmd_line |= IOMMU_CMD_LINE_DMA_API;
2980 iommu_def_domain_type = IOMMU_DOMAIN_DMA;
2981}
2982
2983bool iommu_default_passthrough(void)
2984{
2985 return iommu_def_domain_type == IOMMU_DOMAIN_IDENTITY;
2986}
2987EXPORT_SYMBOL_GPL(iommu_default_passthrough);
2988
2989const struct iommu_ops *iommu_ops_from_fwnode(struct fwnode_handle *fwnode)
2990{
2991 const struct iommu_ops *ops = NULL;
2992 struct iommu_device *iommu;
2993
2994 spin_lock(&iommu_device_lock);
2995 list_for_each_entry(iommu, &iommu_device_list, list)
2996 if (iommu->fwnode == fwnode) {
2997 ops = iommu->ops;
2998 break;
2999 }
3000 spin_unlock(&iommu_device_lock);
3001 return ops;
3002}
3003
3004int iommu_fwspec_init(struct device *dev, struct fwnode_handle *iommu_fwnode,
3005 const struct iommu_ops *ops)
3006{
3007 struct iommu_fwspec *fwspec = dev_iommu_fwspec_get(dev);
3008
3009 if (fwspec)
3010 return ops == fwspec->ops ? 0 : -EINVAL;
3011
3012 if (!dev_iommu_get(dev))
3013 return -ENOMEM;
3014
3015 /* Preallocate for the overwhelmingly common case of 1 ID */
3016 fwspec = kzalloc(struct_size(fwspec, ids, 1), GFP_KERNEL);
3017 if (!fwspec)
3018 return -ENOMEM;
3019
3020 of_node_get(to_of_node(iommu_fwnode));
3021 fwspec->iommu_fwnode = iommu_fwnode;
3022 fwspec->ops = ops;
3023 dev_iommu_fwspec_set(dev, fwspec);
3024 return 0;
3025}
3026EXPORT_SYMBOL_GPL(iommu_fwspec_init);
3027
3028void iommu_fwspec_free(struct device *dev)
3029{
3030 struct iommu_fwspec *fwspec = dev_iommu_fwspec_get(dev);
3031
3032 if (fwspec) {
3033 fwnode_handle_put(fwspec->iommu_fwnode);
3034 kfree(fwspec);
3035 dev_iommu_fwspec_set(dev, NULL);
3036 }
3037}
3038EXPORT_SYMBOL_GPL(iommu_fwspec_free);
3039
3040int iommu_fwspec_add_ids(struct device *dev, u32 *ids, int num_ids)
3041{
3042 struct iommu_fwspec *fwspec = dev_iommu_fwspec_get(dev);
3043 int i, new_num;
3044
3045 if (!fwspec)
3046 return -EINVAL;
3047
3048 new_num = fwspec->num_ids + num_ids;
3049 if (new_num > 1) {
3050 fwspec = krealloc(fwspec, struct_size(fwspec, ids, new_num),
3051 GFP_KERNEL);
3052 if (!fwspec)
3053 return -ENOMEM;
3054
3055 dev_iommu_fwspec_set(dev, fwspec);
3056 }
3057
3058 for (i = 0; i < num_ids; i++)
3059 fwspec->ids[fwspec->num_ids + i] = ids[i];
3060
3061 fwspec->num_ids = new_num;
3062 return 0;
3063}
3064EXPORT_SYMBOL_GPL(iommu_fwspec_add_ids);
3065
3066/*
3067 * Per device IOMMU features.
3068 */
3069int iommu_dev_enable_feature(struct device *dev, enum iommu_dev_features feat)
3070{
3071 if (dev_has_iommu(dev)) {
3072 const struct iommu_ops *ops = dev_iommu_ops(dev);
3073
3074 if (ops->dev_enable_feat)
3075 return ops->dev_enable_feat(dev, feat);
3076 }
3077
3078 return -ENODEV;
3079}
3080EXPORT_SYMBOL_GPL(iommu_dev_enable_feature);
3081
3082/*
3083 * The device drivers should do the necessary cleanups before calling this.
3084 */
3085int iommu_dev_disable_feature(struct device *dev, enum iommu_dev_features feat)
3086{
3087 if (dev_has_iommu(dev)) {
3088 const struct iommu_ops *ops = dev_iommu_ops(dev);
3089
3090 if (ops->dev_disable_feat)
3091 return ops->dev_disable_feat(dev, feat);
3092 }
3093
3094 return -EBUSY;
3095}
3096EXPORT_SYMBOL_GPL(iommu_dev_disable_feature);
3097
3098/**
3099 * iommu_setup_default_domain - Set the default_domain for the group
3100 * @group: Group to change
3101 * @target_type: Domain type to set as the default_domain
3102 *
3103 * Allocate a default domain and set it as the current domain on the group. If
3104 * the group already has a default domain it will be changed to the target_type.
3105 * When target_type is 0 the default domain is selected based on driver and
3106 * system preferences.
3107 */
3108static int iommu_setup_default_domain(struct iommu_group *group,
3109 int target_type)
3110{
3111 struct iommu_domain *old_dom = group->default_domain;
3112 struct group_device *gdev;
3113 struct iommu_domain *dom;
3114 bool direct_failed;
3115 int req_type;
3116 int ret;
3117
3118 lockdep_assert_held(&group->mutex);
3119
3120 req_type = iommu_get_default_domain_type(group, target_type);
3121 if (req_type < 0)
3122 return -EINVAL;
3123
3124 dom = iommu_group_alloc_default_domain(group, req_type);
3125 if (IS_ERR(dom))
3126 return PTR_ERR(dom);
3127
3128 if (group->default_domain == dom)
3129 return 0;
3130
3131 /*
3132 * IOMMU_RESV_DIRECT and IOMMU_RESV_DIRECT_RELAXABLE regions must be
3133 * mapped before their device is attached, in order to guarantee
3134 * continuity with any FW activity
3135 */
3136 direct_failed = false;
3137 for_each_group_device(group, gdev) {
3138 if (iommu_create_device_direct_mappings(dom, gdev->dev)) {
3139 direct_failed = true;
3140 dev_warn_once(
3141 gdev->dev->iommu->iommu_dev->dev,
3142 "IOMMU driver was not able to establish FW requested direct mapping.");
3143 }
3144 }
3145
3146 /* We must set default_domain early for __iommu_device_set_domain */
3147 group->default_domain = dom;
3148 if (!group->domain) {
3149 /*
3150 * Drivers are not allowed to fail the first domain attach.
3151 * The only way to recover from this is to fail attaching the
3152 * iommu driver and call ops->release_device. Put the domain
3153 * in group->default_domain so it is freed after.
3154 */
3155 ret = __iommu_group_set_domain_internal(
3156 group, dom, IOMMU_SET_DOMAIN_MUST_SUCCEED);
3157 if (WARN_ON(ret))
3158 goto out_free_old;
3159 } else {
3160 ret = __iommu_group_set_domain(group, dom);
3161 if (ret)
3162 goto err_restore_def_domain;
3163 }
3164
3165 /*
3166 * Drivers are supposed to allow mappings to be installed in a domain
3167 * before device attachment, but some don't. Hack around this defect by
3168 * trying again after attaching. If this happens it means the device
3169 * will not continuously have the IOMMU_RESV_DIRECT map.
3170 */
3171 if (direct_failed) {
3172 for_each_group_device(group, gdev) {
3173 ret = iommu_create_device_direct_mappings(dom, gdev->dev);
3174 if (ret)
3175 goto err_restore_domain;
3176 }
3177 }
3178
3179out_free_old:
3180 if (old_dom)
3181 iommu_domain_free(old_dom);
3182 return ret;
3183
3184err_restore_domain:
3185 if (old_dom)
3186 __iommu_group_set_domain_internal(
3187 group, old_dom, IOMMU_SET_DOMAIN_MUST_SUCCEED);
3188err_restore_def_domain:
3189 if (old_dom) {
3190 iommu_domain_free(dom);
3191 group->default_domain = old_dom;
3192 }
3193 return ret;
3194}
3195
3196/*
3197 * Changing the default domain through sysfs requires the users to unbind the
3198 * drivers from the devices in the iommu group, except for a DMA -> DMA-FQ
3199 * transition. Return failure if this isn't met.
3200 *
3201 * We need to consider the race between this and the device release path.
3202 * group->mutex is used here to guarantee that the device release path
3203 * will not be entered at the same time.
3204 */
3205static ssize_t iommu_group_store_type(struct iommu_group *group,
3206 const char *buf, size_t count)
3207{
3208 struct group_device *gdev;
3209 int ret, req_type;
3210
3211 if (!capable(CAP_SYS_ADMIN) || !capable(CAP_SYS_RAWIO))
3212 return -EACCES;
3213
3214 if (WARN_ON(!group) || !group->default_domain)
3215 return -EINVAL;
3216
3217 if (sysfs_streq(buf, "identity"))
3218 req_type = IOMMU_DOMAIN_IDENTITY;
3219 else if (sysfs_streq(buf, "DMA"))
3220 req_type = IOMMU_DOMAIN_DMA;
3221 else if (sysfs_streq(buf, "DMA-FQ"))
3222 req_type = IOMMU_DOMAIN_DMA_FQ;
3223 else if (sysfs_streq(buf, "auto"))
3224 req_type = 0;
3225 else
3226 return -EINVAL;
3227
3228 mutex_lock(&group->mutex);
3229 /* We can bring up a flush queue without tearing down the domain. */
3230 if (req_type == IOMMU_DOMAIN_DMA_FQ &&
3231 group->default_domain->type == IOMMU_DOMAIN_DMA) {
3232 ret = iommu_dma_init_fq(group->default_domain);
3233 if (ret)
3234 goto out_unlock;
3235
3236 group->default_domain->type = IOMMU_DOMAIN_DMA_FQ;
3237 ret = count;
3238 goto out_unlock;
3239 }
3240
3241 /* Otherwise, ensure that device exists and no driver is bound. */
3242 if (list_empty(&group->devices) || group->owner_cnt) {
3243 ret = -EPERM;
3244 goto out_unlock;
3245 }
3246
3247 ret = iommu_setup_default_domain(group, req_type);
3248 if (ret)
3249 goto out_unlock;
3250
3251 /*
3252 * Release the mutex here because ops->probe_finalize() call-back of
3253 * some vendor IOMMU drivers calls arm_iommu_attach_device() which
3254 * in-turn might call back into IOMMU core code, where it tries to take
3255 * group->mutex, resulting in a deadlock.
3256 */
3257 mutex_unlock(&group->mutex);
3258
3259 /* Make sure dma_ops is appropriatley set */
3260 for_each_group_device(group, gdev)
3261 iommu_group_do_probe_finalize(gdev->dev);
3262 return count;
3263
3264out_unlock:
3265 mutex_unlock(&group->mutex);
3266 return ret ?: count;
3267}
3268
3269/**
3270 * iommu_device_use_default_domain() - Device driver wants to handle device
3271 * DMA through the kernel DMA API.
3272 * @dev: The device.
3273 *
3274 * The device driver about to bind @dev wants to do DMA through the kernel
3275 * DMA API. Return 0 if it is allowed, otherwise an error.
3276 */
3277int iommu_device_use_default_domain(struct device *dev)
3278{
3279 /* Caller is the driver core during the pre-probe path */
3280 struct iommu_group *group = dev->iommu_group;
3281 int ret = 0;
3282
3283 if (!group)
3284 return 0;
3285
3286 mutex_lock(&group->mutex);
3287 if (group->owner_cnt) {
3288 if (group->domain != group->default_domain || group->owner ||
3289 !xa_empty(&group->pasid_array)) {
3290 ret = -EBUSY;
3291 goto unlock_out;
3292 }
3293 }
3294
3295 group->owner_cnt++;
3296
3297unlock_out:
3298 mutex_unlock(&group->mutex);
3299 return ret;
3300}
3301
3302/**
3303 * iommu_device_unuse_default_domain() - Device driver stops handling device
3304 * DMA through the kernel DMA API.
3305 * @dev: The device.
3306 *
3307 * The device driver doesn't want to do DMA through kernel DMA API anymore.
3308 * It must be called after iommu_device_use_default_domain().
3309 */
3310void iommu_device_unuse_default_domain(struct device *dev)
3311{
3312 /* Caller is the driver core during the post-probe path */
3313 struct iommu_group *group = dev->iommu_group;
3314
3315 if (!group)
3316 return;
3317
3318 mutex_lock(&group->mutex);
3319 if (!WARN_ON(!group->owner_cnt || !xa_empty(&group->pasid_array)))
3320 group->owner_cnt--;
3321
3322 mutex_unlock(&group->mutex);
3323}
3324
3325static int __iommu_group_alloc_blocking_domain(struct iommu_group *group)
3326{
3327 struct iommu_domain *domain;
3328
3329 if (group->blocking_domain)
3330 return 0;
3331
3332 domain = __iommu_group_domain_alloc(group, IOMMU_DOMAIN_BLOCKED);
3333 if (IS_ERR(domain)) {
3334 /*
3335 * For drivers that do not yet understand IOMMU_DOMAIN_BLOCKED
3336 * create an empty domain instead.
3337 */
3338 domain = __iommu_group_domain_alloc(group,
3339 IOMMU_DOMAIN_UNMANAGED);
3340 if (IS_ERR(domain))
3341 return PTR_ERR(domain);
3342 }
3343 group->blocking_domain = domain;
3344 return 0;
3345}
3346
3347static int __iommu_take_dma_ownership(struct iommu_group *group, void *owner)
3348{
3349 int ret;
3350
3351 if ((group->domain && group->domain != group->default_domain) ||
3352 !xa_empty(&group->pasid_array))
3353 return -EBUSY;
3354
3355 ret = __iommu_group_alloc_blocking_domain(group);
3356 if (ret)
3357 return ret;
3358 ret = __iommu_group_set_domain(group, group->blocking_domain);
3359 if (ret)
3360 return ret;
3361
3362 group->owner = owner;
3363 group->owner_cnt++;
3364 return 0;
3365}
3366
3367/**
3368 * iommu_group_claim_dma_owner() - Set DMA ownership of a group
3369 * @group: The group.
3370 * @owner: Caller specified pointer. Used for exclusive ownership.
3371 *
3372 * This is to support backward compatibility for vfio which manages the dma
3373 * ownership in iommu_group level. New invocations on this interface should be
3374 * prohibited. Only a single owner may exist for a group.
3375 */
3376int iommu_group_claim_dma_owner(struct iommu_group *group, void *owner)
3377{
3378 int ret = 0;
3379
3380 if (WARN_ON(!owner))
3381 return -EINVAL;
3382
3383 mutex_lock(&group->mutex);
3384 if (group->owner_cnt) {
3385 ret = -EPERM;
3386 goto unlock_out;
3387 }
3388
3389 ret = __iommu_take_dma_ownership(group, owner);
3390unlock_out:
3391 mutex_unlock(&group->mutex);
3392
3393 return ret;
3394}
3395EXPORT_SYMBOL_GPL(iommu_group_claim_dma_owner);
3396
3397/**
3398 * iommu_device_claim_dma_owner() - Set DMA ownership of a device
3399 * @dev: The device.
3400 * @owner: Caller specified pointer. Used for exclusive ownership.
3401 *
3402 * Claim the DMA ownership of a device. Multiple devices in the same group may
3403 * concurrently claim ownership if they present the same owner value. Returns 0
3404 * on success and error code on failure
3405 */
3406int iommu_device_claim_dma_owner(struct device *dev, void *owner)
3407{
3408 /* Caller must be a probed driver on dev */
3409 struct iommu_group *group = dev->iommu_group;
3410 int ret = 0;
3411
3412 if (WARN_ON(!owner))
3413 return -EINVAL;
3414
3415 if (!group)
3416 return -ENODEV;
3417
3418 mutex_lock(&group->mutex);
3419 if (group->owner_cnt) {
3420 if (group->owner != owner) {
3421 ret = -EPERM;
3422 goto unlock_out;
3423 }
3424 group->owner_cnt++;
3425 goto unlock_out;
3426 }
3427
3428 ret = __iommu_take_dma_ownership(group, owner);
3429unlock_out:
3430 mutex_unlock(&group->mutex);
3431 return ret;
3432}
3433EXPORT_SYMBOL_GPL(iommu_device_claim_dma_owner);
3434
3435static void __iommu_release_dma_ownership(struct iommu_group *group)
3436{
3437 if (WARN_ON(!group->owner_cnt || !group->owner ||
3438 !xa_empty(&group->pasid_array)))
3439 return;
3440
3441 group->owner_cnt = 0;
3442 group->owner = NULL;
3443 __iommu_group_set_domain_nofail(group, group->default_domain);
3444}
3445
3446/**
3447 * iommu_group_release_dma_owner() - Release DMA ownership of a group
3448 * @group: The group
3449 *
3450 * Release the DMA ownership claimed by iommu_group_claim_dma_owner().
3451 */
3452void iommu_group_release_dma_owner(struct iommu_group *group)
3453{
3454 mutex_lock(&group->mutex);
3455 __iommu_release_dma_ownership(group);
3456 mutex_unlock(&group->mutex);
3457}
3458EXPORT_SYMBOL_GPL(iommu_group_release_dma_owner);
3459
3460/**
3461 * iommu_device_release_dma_owner() - Release DMA ownership of a device
3462 * @dev: The device.
3463 *
3464 * Release the DMA ownership claimed by iommu_device_claim_dma_owner().
3465 */
3466void iommu_device_release_dma_owner(struct device *dev)
3467{
3468 /* Caller must be a probed driver on dev */
3469 struct iommu_group *group = dev->iommu_group;
3470
3471 mutex_lock(&group->mutex);
3472 if (group->owner_cnt > 1)
3473 group->owner_cnt--;
3474 else
3475 __iommu_release_dma_ownership(group);
3476 mutex_unlock(&group->mutex);
3477}
3478EXPORT_SYMBOL_GPL(iommu_device_release_dma_owner);
3479
3480/**
3481 * iommu_group_dma_owner_claimed() - Query group dma ownership status
3482 * @group: The group.
3483 *
3484 * This provides status query on a given group. It is racy and only for
3485 * non-binding status reporting.
3486 */
3487bool iommu_group_dma_owner_claimed(struct iommu_group *group)
3488{
3489 unsigned int user;
3490
3491 mutex_lock(&group->mutex);
3492 user = group->owner_cnt;
3493 mutex_unlock(&group->mutex);
3494
3495 return user;
3496}
3497EXPORT_SYMBOL_GPL(iommu_group_dma_owner_claimed);
3498
3499static int __iommu_set_group_pasid(struct iommu_domain *domain,
3500 struct iommu_group *group, ioasid_t pasid)
3501{
3502 struct group_device *device;
3503 int ret = 0;
3504
3505 for_each_group_device(group, device) {
3506 ret = domain->ops->set_dev_pasid(domain, device->dev, pasid);
3507 if (ret)
3508 break;
3509 }
3510
3511 return ret;
3512}
3513
3514static void __iommu_remove_group_pasid(struct iommu_group *group,
3515 ioasid_t pasid)
3516{
3517 struct group_device *device;
3518 const struct iommu_ops *ops;
3519
3520 for_each_group_device(group, device) {
3521 ops = dev_iommu_ops(device->dev);
3522 ops->remove_dev_pasid(device->dev, pasid);
3523 }
3524}
3525
3526/*
3527 * iommu_attach_device_pasid() - Attach a domain to pasid of device
3528 * @domain: the iommu domain.
3529 * @dev: the attached device.
3530 * @pasid: the pasid of the device.
3531 *
3532 * Return: 0 on success, or an error.
3533 */
3534int iommu_attach_device_pasid(struct iommu_domain *domain,
3535 struct device *dev, ioasid_t pasid)
3536{
3537 /* Caller must be a probed driver on dev */
3538 struct iommu_group *group = dev->iommu_group;
3539 void *curr;
3540 int ret;
3541
3542 if (!domain->ops->set_dev_pasid)
3543 return -EOPNOTSUPP;
3544
3545 if (!group)
3546 return -ENODEV;
3547
3548 if (!dev_has_iommu(dev) || dev_iommu_ops(dev) != domain->owner)
3549 return -EINVAL;
3550
3551 mutex_lock(&group->mutex);
3552 curr = xa_cmpxchg(&group->pasid_array, pasid, NULL, domain, GFP_KERNEL);
3553 if (curr) {
3554 ret = xa_err(curr) ? : -EBUSY;
3555 goto out_unlock;
3556 }
3557
3558 ret = __iommu_set_group_pasid(domain, group, pasid);
3559 if (ret) {
3560 __iommu_remove_group_pasid(group, pasid);
3561 xa_erase(&group->pasid_array, pasid);
3562 }
3563out_unlock:
3564 mutex_unlock(&group->mutex);
3565 return ret;
3566}
3567EXPORT_SYMBOL_GPL(iommu_attach_device_pasid);
3568
3569/*
3570 * iommu_detach_device_pasid() - Detach the domain from pasid of device
3571 * @domain: the iommu domain.
3572 * @dev: the attached device.
3573 * @pasid: the pasid of the device.
3574 *
3575 * The @domain must have been attached to @pasid of the @dev with
3576 * iommu_attach_device_pasid().
3577 */
3578void iommu_detach_device_pasid(struct iommu_domain *domain, struct device *dev,
3579 ioasid_t pasid)
3580{
3581 /* Caller must be a probed driver on dev */
3582 struct iommu_group *group = dev->iommu_group;
3583
3584 mutex_lock(&group->mutex);
3585 __iommu_remove_group_pasid(group, pasid);
3586 WARN_ON(xa_erase(&group->pasid_array, pasid) != domain);
3587 mutex_unlock(&group->mutex);
3588}
3589EXPORT_SYMBOL_GPL(iommu_detach_device_pasid);
3590
3591/*
3592 * iommu_get_domain_for_dev_pasid() - Retrieve domain for @pasid of @dev
3593 * @dev: the queried device
3594 * @pasid: the pasid of the device
3595 * @type: matched domain type, 0 for any match
3596 *
3597 * This is a variant of iommu_get_domain_for_dev(). It returns the existing
3598 * domain attached to pasid of a device. Callers must hold a lock around this
3599 * function, and both iommu_attach/detach_dev_pasid() whenever a domain of
3600 * type is being manipulated. This API does not internally resolve races with
3601 * attach/detach.
3602 *
3603 * Return: attached domain on success, NULL otherwise.
3604 */
3605struct iommu_domain *iommu_get_domain_for_dev_pasid(struct device *dev,
3606 ioasid_t pasid,
3607 unsigned int type)
3608{
3609 /* Caller must be a probed driver on dev */
3610 struct iommu_group *group = dev->iommu_group;
3611 struct iommu_domain *domain;
3612
3613 if (!group)
3614 return NULL;
3615
3616 xa_lock(&group->pasid_array);
3617 domain = xa_load(&group->pasid_array, pasid);
3618 if (type && domain && domain->type != type)
3619 domain = ERR_PTR(-EBUSY);
3620 xa_unlock(&group->pasid_array);
3621
3622 return domain;
3623}
3624EXPORT_SYMBOL_GPL(iommu_get_domain_for_dev_pasid);
3625
3626struct iommu_domain *iommu_sva_domain_alloc(struct device *dev,
3627 struct mm_struct *mm)
3628{
3629 const struct iommu_ops *ops = dev_iommu_ops(dev);
3630 struct iommu_domain *domain;
3631
3632 domain = ops->domain_alloc(IOMMU_DOMAIN_SVA);
3633 if (!domain)
3634 return NULL;
3635
3636 domain->type = IOMMU_DOMAIN_SVA;
3637 mmgrab(mm);
3638 domain->mm = mm;
3639 domain->owner = ops;
3640 domain->iopf_handler = iommu_sva_handle_iopf;
3641 domain->fault_data = mm;
3642
3643 return domain;
3644}
3645
3646ioasid_t iommu_alloc_global_pasid(struct device *dev)
3647{
3648 int ret;
3649
3650 /* max_pasids == 0 means that the device does not support PASID */
3651 if (!dev->iommu->max_pasids)
3652 return IOMMU_PASID_INVALID;
3653
3654 /*
3655 * max_pasids is set up by vendor driver based on number of PASID bits
3656 * supported but the IDA allocation is inclusive.
3657 */
3658 ret = ida_alloc_range(&iommu_global_pasid_ida, IOMMU_FIRST_GLOBAL_PASID,
3659 dev->iommu->max_pasids - 1, GFP_KERNEL);
3660 return ret < 0 ? IOMMU_PASID_INVALID : ret;
3661}
3662EXPORT_SYMBOL_GPL(iommu_alloc_global_pasid);
3663
3664void iommu_free_global_pasid(ioasid_t pasid)
3665{
3666 if (WARN_ON(pasid == IOMMU_PASID_INVALID))
3667 return;
3668
3669 ida_free(&iommu_global_pasid_ida, pasid);
3670}
3671EXPORT_SYMBOL_GPL(iommu_free_global_pasid);