1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3 * Copyright (C) 2010-2012 Advanced Micro Devices, Inc.
4 * Author: Joerg Roedel <jroedel@suse.de>
5 */
6
7 #define pr_fmt(fmt) "AMD-Vi: " fmt
8
9 #include <linux/refcount.h>
10 #include <linux/mmu_notifier.h>
11 #include <linux/amd-iommu.h>
12 #include <linux/mm_types.h>
13 #include <linux/profile.h>
14 #include <linux/module.h>
15 #include <linux/sched.h>
16 #include <linux/sched/mm.h>
17 #include <linux/wait.h>
18 #include <linux/pci.h>
19 #include <linux/gfp.h>
20 #include <linux/cc_platform.h>
21
22 #include "amd_iommu.h"
23
24 MODULE_LICENSE("GPL v2");
25 MODULE_AUTHOR("Joerg Roedel <jroedel@suse.de>");
26
27 #define PRI_QUEUE_SIZE 512
28
29 struct pri_queue {
30 atomic_t inflight;
31 bool finish;
32 int status;
33 };
34
35 struct pasid_state {
36 struct list_head list; /* For global state-list */
37 refcount_t count; /* Reference count */
38 unsigned mmu_notifier_count; /* Counting nested mmu_notifier
39 calls */
40 struct mm_struct *mm; /* mm_struct for the faults */
41 struct mmu_notifier mn; /* mmu_notifier handle */
42 struct pri_queue pri[PRI_QUEUE_SIZE]; /* PRI tag states */
43 struct device_state *device_state; /* Link to our device_state */
44 u32 pasid; /* PASID index */
45 bool invalid; /* Used during setup and
46 teardown of the pasid */
47 spinlock_t lock; /* Protect pri_queues and
48 mmu_notifer_count */
49 wait_queue_head_t wq; /* To wait for count == 0 */
50 };
51
52 struct device_state {
53 struct list_head list;
54 u32 sbdf;
55 atomic_t count;
56 struct pci_dev *pdev;
57 struct pasid_state **states;
58 struct iommu_domain *domain;
59 int pasid_levels;
60 int max_pasids;
61 amd_iommu_invalid_ppr_cb inv_ppr_cb;
62 amd_iommu_invalidate_ctx inv_ctx_cb;
63 spinlock_t lock;
64 wait_queue_head_t wq;
65 };
66
67 struct fault {
68 struct work_struct work;
69 struct device_state *dev_state;
70 struct pasid_state *state;
71 struct mm_struct *mm;
72 u64 address;
73 u32 pasid;
74 u16 tag;
75 u16 finish;
76 u16 flags;
77 };
78
79 static LIST_HEAD(state_list);
80 static DEFINE_SPINLOCK(state_lock);
81
82 static struct workqueue_struct *iommu_wq;
83
84 static void free_pasid_states(struct device_state *dev_state);
85
__get_device_state(u32 sbdf)86 static struct device_state *__get_device_state(u32 sbdf)
87 {
88 struct device_state *dev_state;
89
90 list_for_each_entry(dev_state, &state_list, list) {
91 if (dev_state->sbdf == sbdf)
92 return dev_state;
93 }
94
95 return NULL;
96 }
97
get_device_state(u32 sbdf)98 static struct device_state *get_device_state(u32 sbdf)
99 {
100 struct device_state *dev_state;
101 unsigned long flags;
102
103 spin_lock_irqsave(&state_lock, flags);
104 dev_state = __get_device_state(sbdf);
105 if (dev_state != NULL)
106 atomic_inc(&dev_state->count);
107 spin_unlock_irqrestore(&state_lock, flags);
108
109 return dev_state;
110 }
111
free_device_state(struct device_state * dev_state)112 static void free_device_state(struct device_state *dev_state)
113 {
114 struct iommu_group *group;
115
116 /* Get rid of any remaining pasid states */
117 free_pasid_states(dev_state);
118
119 /*
120 * Wait until the last reference is dropped before freeing
121 * the device state.
122 */
123 wait_event(dev_state->wq, !atomic_read(&dev_state->count));
124
125 /*
126 * First detach device from domain - No more PRI requests will arrive
127 * from that device after it is unbound from the IOMMUv2 domain.
128 */
129 group = iommu_group_get(&dev_state->pdev->dev);
130 if (WARN_ON(!group))
131 return;
132
133 iommu_detach_group(dev_state->domain, group);
134
135 iommu_group_put(group);
136
137 /* Everything is down now, free the IOMMUv2 domain */
138 iommu_domain_free(dev_state->domain);
139
140 /* Finally get rid of the device-state */
141 kfree(dev_state);
142 }
143
put_device_state(struct device_state * dev_state)144 static void put_device_state(struct device_state *dev_state)
145 {
146 if (atomic_dec_and_test(&dev_state->count))
147 wake_up(&dev_state->wq);
148 }
149
150 /* Must be called under dev_state->lock */
__get_pasid_state_ptr(struct device_state * dev_state,u32 pasid,bool alloc)151 static struct pasid_state **__get_pasid_state_ptr(struct device_state *dev_state,
152 u32 pasid, bool alloc)
153 {
154 struct pasid_state **root, **ptr;
155 int level, index;
156
157 level = dev_state->pasid_levels;
158 root = dev_state->states;
159
160 while (true) {
161
162 index = (pasid >> (9 * level)) & 0x1ff;
163 ptr = &root[index];
164
165 if (level == 0)
166 break;
167
168 if (*ptr == NULL) {
169 if (!alloc)
170 return NULL;
171
172 *ptr = (void *)get_zeroed_page(GFP_ATOMIC);
173 if (*ptr == NULL)
174 return NULL;
175 }
176
177 root = (struct pasid_state **)*ptr;
178 level -= 1;
179 }
180
181 return ptr;
182 }
183
set_pasid_state(struct device_state * dev_state,struct pasid_state * pasid_state,u32 pasid)184 static int set_pasid_state(struct device_state *dev_state,
185 struct pasid_state *pasid_state,
186 u32 pasid)
187 {
188 struct pasid_state **ptr;
189 unsigned long flags;
190 int ret;
191
192 spin_lock_irqsave(&dev_state->lock, flags);
193 ptr = __get_pasid_state_ptr(dev_state, pasid, true);
194
195 ret = -ENOMEM;
196 if (ptr == NULL)
197 goto out_unlock;
198
199 ret = -ENOMEM;
200 if (*ptr != NULL)
201 goto out_unlock;
202
203 *ptr = pasid_state;
204
205 ret = 0;
206
207 out_unlock:
208 spin_unlock_irqrestore(&dev_state->lock, flags);
209
210 return ret;
211 }
212
clear_pasid_state(struct device_state * dev_state,u32 pasid)213 static void clear_pasid_state(struct device_state *dev_state, u32 pasid)
214 {
215 struct pasid_state **ptr;
216 unsigned long flags;
217
218 spin_lock_irqsave(&dev_state->lock, flags);
219 ptr = __get_pasid_state_ptr(dev_state, pasid, true);
220
221 if (ptr == NULL)
222 goto out_unlock;
223
224 *ptr = NULL;
225
226 out_unlock:
227 spin_unlock_irqrestore(&dev_state->lock, flags);
228 }
229
get_pasid_state(struct device_state * dev_state,u32 pasid)230 static struct pasid_state *get_pasid_state(struct device_state *dev_state,
231 u32 pasid)
232 {
233 struct pasid_state **ptr, *ret = NULL;
234 unsigned long flags;
235
236 spin_lock_irqsave(&dev_state->lock, flags);
237 ptr = __get_pasid_state_ptr(dev_state, pasid, false);
238
239 if (ptr == NULL)
240 goto out_unlock;
241
242 ret = *ptr;
243 if (ret)
244 refcount_inc(&ret->count);
245
246 out_unlock:
247 spin_unlock_irqrestore(&dev_state->lock, flags);
248
249 return ret;
250 }
251
free_pasid_state(struct pasid_state * pasid_state)252 static void free_pasid_state(struct pasid_state *pasid_state)
253 {
254 kfree(pasid_state);
255 }
256
put_pasid_state(struct pasid_state * pasid_state)257 static void put_pasid_state(struct pasid_state *pasid_state)
258 {
259 if (refcount_dec_and_test(&pasid_state->count))
260 wake_up(&pasid_state->wq);
261 }
262
put_pasid_state_wait(struct pasid_state * pasid_state)263 static void put_pasid_state_wait(struct pasid_state *pasid_state)
264 {
265 if (!refcount_dec_and_test(&pasid_state->count))
266 wait_event(pasid_state->wq, !refcount_read(&pasid_state->count));
267 free_pasid_state(pasid_state);
268 }
269
unbind_pasid(struct pasid_state * pasid_state)270 static void unbind_pasid(struct pasid_state *pasid_state)
271 {
272 struct iommu_domain *domain;
273
274 domain = pasid_state->device_state->domain;
275
276 /*
277 * Mark pasid_state as invalid, no more faults will we added to the
278 * work queue after this is visible everywhere.
279 */
280 pasid_state->invalid = true;
281
282 /* Make sure this is visible */
283 smp_wmb();
284
285 /* After this the device/pasid can't access the mm anymore */
286 amd_iommu_domain_clear_gcr3(domain, pasid_state->pasid);
287
288 /* Make sure no more pending faults are in the queue */
289 flush_workqueue(iommu_wq);
290 }
291
free_pasid_states_level1(struct pasid_state ** tbl)292 static void free_pasid_states_level1(struct pasid_state **tbl)
293 {
294 int i;
295
296 for (i = 0; i < 512; ++i) {
297 if (tbl[i] == NULL)
298 continue;
299
300 free_page((unsigned long)tbl[i]);
301 }
302 }
303
free_pasid_states_level2(struct pasid_state ** tbl)304 static void free_pasid_states_level2(struct pasid_state **tbl)
305 {
306 struct pasid_state **ptr;
307 int i;
308
309 for (i = 0; i < 512; ++i) {
310 if (tbl[i] == NULL)
311 continue;
312
313 ptr = (struct pasid_state **)tbl[i];
314 free_pasid_states_level1(ptr);
315 }
316 }
317
free_pasid_states(struct device_state * dev_state)318 static void free_pasid_states(struct device_state *dev_state)
319 {
320 struct pasid_state *pasid_state;
321 int i;
322
323 for (i = 0; i < dev_state->max_pasids; ++i) {
324 pasid_state = get_pasid_state(dev_state, i);
325 if (pasid_state == NULL)
326 continue;
327
328 put_pasid_state(pasid_state);
329
330 /* Clear the pasid state so that the pasid can be re-used */
331 clear_pasid_state(dev_state, pasid_state->pasid);
332
333 /*
334 * This will call the mn_release function and
335 * unbind the PASID
336 */
337 mmu_notifier_unregister(&pasid_state->mn, pasid_state->mm);
338
339 put_pasid_state_wait(pasid_state); /* Reference taken in
340 amd_iommu_bind_pasid */
341
342 /* Drop reference taken in amd_iommu_bind_pasid */
343 put_device_state(dev_state);
344 }
345
346 if (dev_state->pasid_levels == 2)
347 free_pasid_states_level2(dev_state->states);
348 else if (dev_state->pasid_levels == 1)
349 free_pasid_states_level1(dev_state->states);
350 else
351 BUG_ON(dev_state->pasid_levels != 0);
352
353 free_page((unsigned long)dev_state->states);
354 }
355
mn_to_state(struct mmu_notifier * mn)356 static struct pasid_state *mn_to_state(struct mmu_notifier *mn)
357 {
358 return container_of(mn, struct pasid_state, mn);
359 }
360
mn_arch_invalidate_secondary_tlbs(struct mmu_notifier * mn,struct mm_struct * mm,unsigned long start,unsigned long end)361 static void mn_arch_invalidate_secondary_tlbs(struct mmu_notifier *mn,
362 struct mm_struct *mm,
363 unsigned long start, unsigned long end)
364 {
365 struct pasid_state *pasid_state;
366 struct device_state *dev_state;
367
368 pasid_state = mn_to_state(mn);
369 dev_state = pasid_state->device_state;
370
371 if ((start ^ (end - 1)) < PAGE_SIZE)
372 amd_iommu_flush_page(dev_state->domain, pasid_state->pasid,
373 start);
374 else
375 amd_iommu_flush_tlb(dev_state->domain, pasid_state->pasid);
376 }
377
mn_release(struct mmu_notifier * mn,struct mm_struct * mm)378 static void mn_release(struct mmu_notifier *mn, struct mm_struct *mm)
379 {
380 struct pasid_state *pasid_state;
381 struct device_state *dev_state;
382 bool run_inv_ctx_cb;
383
384 might_sleep();
385
386 pasid_state = mn_to_state(mn);
387 dev_state = pasid_state->device_state;
388 run_inv_ctx_cb = !pasid_state->invalid;
389
390 if (run_inv_ctx_cb && dev_state->inv_ctx_cb)
391 dev_state->inv_ctx_cb(dev_state->pdev, pasid_state->pasid);
392
393 unbind_pasid(pasid_state);
394 }
395
396 static const struct mmu_notifier_ops iommu_mn = {
397 .release = mn_release,
398 .arch_invalidate_secondary_tlbs = mn_arch_invalidate_secondary_tlbs,
399 };
400
set_pri_tag_status(struct pasid_state * pasid_state,u16 tag,int status)401 static void set_pri_tag_status(struct pasid_state *pasid_state,
402 u16 tag, int status)
403 {
404 unsigned long flags;
405
406 spin_lock_irqsave(&pasid_state->lock, flags);
407 pasid_state->pri[tag].status = status;
408 spin_unlock_irqrestore(&pasid_state->lock, flags);
409 }
410
finish_pri_tag(struct device_state * dev_state,struct pasid_state * pasid_state,u16 tag)411 static void finish_pri_tag(struct device_state *dev_state,
412 struct pasid_state *pasid_state,
413 u16 tag)
414 {
415 unsigned long flags;
416
417 spin_lock_irqsave(&pasid_state->lock, flags);
418 if (atomic_dec_and_test(&pasid_state->pri[tag].inflight) &&
419 pasid_state->pri[tag].finish) {
420 amd_iommu_complete_ppr(dev_state->pdev, pasid_state->pasid,
421 pasid_state->pri[tag].status, tag);
422 pasid_state->pri[tag].finish = false;
423 pasid_state->pri[tag].status = PPR_SUCCESS;
424 }
425 spin_unlock_irqrestore(&pasid_state->lock, flags);
426 }
427
handle_fault_error(struct fault * fault)428 static void handle_fault_error(struct fault *fault)
429 {
430 int status;
431
432 if (!fault->dev_state->inv_ppr_cb) {
433 set_pri_tag_status(fault->state, fault->tag, PPR_INVALID);
434 return;
435 }
436
437 status = fault->dev_state->inv_ppr_cb(fault->dev_state->pdev,
438 fault->pasid,
439 fault->address,
440 fault->flags);
441 switch (status) {
442 case AMD_IOMMU_INV_PRI_RSP_SUCCESS:
443 set_pri_tag_status(fault->state, fault->tag, PPR_SUCCESS);
444 break;
445 case AMD_IOMMU_INV_PRI_RSP_INVALID:
446 set_pri_tag_status(fault->state, fault->tag, PPR_INVALID);
447 break;
448 case AMD_IOMMU_INV_PRI_RSP_FAIL:
449 set_pri_tag_status(fault->state, fault->tag, PPR_FAILURE);
450 break;
451 default:
452 BUG();
453 }
454 }
455
access_error(struct vm_area_struct * vma,struct fault * fault)456 static bool access_error(struct vm_area_struct *vma, struct fault *fault)
457 {
458 unsigned long requested = 0;
459
460 if (fault->flags & PPR_FAULT_EXEC)
461 requested |= VM_EXEC;
462
463 if (fault->flags & PPR_FAULT_READ)
464 requested |= VM_READ;
465
466 if (fault->flags & PPR_FAULT_WRITE)
467 requested |= VM_WRITE;
468
469 return (requested & ~vma->vm_flags) != 0;
470 }
471
do_fault(struct work_struct * work)472 static void do_fault(struct work_struct *work)
473 {
474 struct fault *fault = container_of(work, struct fault, work);
475 struct vm_area_struct *vma;
476 vm_fault_t ret = VM_FAULT_ERROR;
477 unsigned int flags = 0;
478 struct mm_struct *mm;
479 u64 address;
480
481 mm = fault->state->mm;
482 address = fault->address;
483
484 if (fault->flags & PPR_FAULT_USER)
485 flags |= FAULT_FLAG_USER;
486 if (fault->flags & PPR_FAULT_WRITE)
487 flags |= FAULT_FLAG_WRITE;
488 flags |= FAULT_FLAG_REMOTE;
489
490 mmap_read_lock(mm);
491 vma = vma_lookup(mm, address);
492 if (!vma)
493 /* failed to get a vma in the right range */
494 goto out;
495
496 /* Check if we have the right permissions on the vma */
497 if (access_error(vma, fault))
498 goto out;
499
500 ret = handle_mm_fault(vma, address, flags, NULL);
501 out:
502 mmap_read_unlock(mm);
503
504 if (ret & VM_FAULT_ERROR)
505 /* failed to service fault */
506 handle_fault_error(fault);
507
508 finish_pri_tag(fault->dev_state, fault->state, fault->tag);
509
510 put_pasid_state(fault->state);
511
512 kfree(fault);
513 }
514
ppr_notifier(struct notifier_block * nb,unsigned long e,void * data)515 static int ppr_notifier(struct notifier_block *nb, unsigned long e, void *data)
516 {
517 struct amd_iommu_fault *iommu_fault;
518 struct pasid_state *pasid_state;
519 struct device_state *dev_state;
520 struct pci_dev *pdev = NULL;
521 unsigned long flags;
522 struct fault *fault;
523 bool finish;
524 u16 tag, devid, seg_id;
525 int ret;
526
527 iommu_fault = data;
528 tag = iommu_fault->tag & 0x1ff;
529 finish = (iommu_fault->tag >> 9) & 1;
530
531 seg_id = PCI_SBDF_TO_SEGID(iommu_fault->sbdf);
532 devid = PCI_SBDF_TO_DEVID(iommu_fault->sbdf);
533 pdev = pci_get_domain_bus_and_slot(seg_id, PCI_BUS_NUM(devid),
534 devid & 0xff);
535 if (!pdev)
536 return -ENODEV;
537
538 ret = NOTIFY_DONE;
539
540 /* In kdump kernel pci dev is not initialized yet -> send INVALID */
541 if (amd_iommu_is_attach_deferred(&pdev->dev)) {
542 amd_iommu_complete_ppr(pdev, iommu_fault->pasid,
543 PPR_INVALID, tag);
544 goto out;
545 }
546
547 dev_state = get_device_state(iommu_fault->sbdf);
548 if (dev_state == NULL)
549 goto out;
550
551 pasid_state = get_pasid_state(dev_state, iommu_fault->pasid);
552 if (pasid_state == NULL || pasid_state->invalid) {
553 /* We know the device but not the PASID -> send INVALID */
554 amd_iommu_complete_ppr(dev_state->pdev, iommu_fault->pasid,
555 PPR_INVALID, tag);
556 goto out_drop_state;
557 }
558
559 spin_lock_irqsave(&pasid_state->lock, flags);
560 atomic_inc(&pasid_state->pri[tag].inflight);
561 if (finish)
562 pasid_state->pri[tag].finish = true;
563 spin_unlock_irqrestore(&pasid_state->lock, flags);
564
565 fault = kzalloc(sizeof(*fault), GFP_ATOMIC);
566 if (fault == NULL) {
567 /* We are OOM - send success and let the device re-fault */
568 finish_pri_tag(dev_state, pasid_state, tag);
569 goto out_drop_state;
570 }
571
572 fault->dev_state = dev_state;
573 fault->address = iommu_fault->address;
574 fault->state = pasid_state;
575 fault->tag = tag;
576 fault->finish = finish;
577 fault->pasid = iommu_fault->pasid;
578 fault->flags = iommu_fault->flags;
579 INIT_WORK(&fault->work, do_fault);
580
581 queue_work(iommu_wq, &fault->work);
582
583 ret = NOTIFY_OK;
584
585 out_drop_state:
586
587 if (ret != NOTIFY_OK && pasid_state)
588 put_pasid_state(pasid_state);
589
590 put_device_state(dev_state);
591
592 out:
593 pci_dev_put(pdev);
594 return ret;
595 }
596
597 static struct notifier_block ppr_nb = {
598 .notifier_call = ppr_notifier,
599 };
600
amd_iommu_bind_pasid(struct pci_dev * pdev,u32 pasid,struct task_struct * task)601 int amd_iommu_bind_pasid(struct pci_dev *pdev, u32 pasid,
602 struct task_struct *task)
603 {
604 struct pasid_state *pasid_state;
605 struct device_state *dev_state;
606 struct mm_struct *mm;
607 u32 sbdf;
608 int ret;
609
610 might_sleep();
611
612 if (!amd_iommu_v2_supported())
613 return -ENODEV;
614
615 sbdf = get_pci_sbdf_id(pdev);
616 dev_state = get_device_state(sbdf);
617
618 if (dev_state == NULL)
619 return -EINVAL;
620
621 ret = -EINVAL;
622 if (pasid >= dev_state->max_pasids)
623 goto out;
624
625 ret = -ENOMEM;
626 pasid_state = kzalloc(sizeof(*pasid_state), GFP_KERNEL);
627 if (pasid_state == NULL)
628 goto out;
629
630
631 refcount_set(&pasid_state->count, 1);
632 init_waitqueue_head(&pasid_state->wq);
633 spin_lock_init(&pasid_state->lock);
634
635 mm = get_task_mm(task);
636 pasid_state->mm = mm;
637 pasid_state->device_state = dev_state;
638 pasid_state->pasid = pasid;
639 pasid_state->invalid = true; /* Mark as valid only if we are
640 done with setting up the pasid */
641 pasid_state->mn.ops = &iommu_mn;
642
643 if (pasid_state->mm == NULL)
644 goto out_free;
645
646 ret = mmu_notifier_register(&pasid_state->mn, mm);
647 if (ret)
648 goto out_free;
649
650 ret = set_pasid_state(dev_state, pasid_state, pasid);
651 if (ret)
652 goto out_unregister;
653
654 ret = amd_iommu_domain_set_gcr3(dev_state->domain, pasid,
655 __pa(pasid_state->mm->pgd));
656 if (ret)
657 goto out_clear_state;
658
659 /* Now we are ready to handle faults */
660 pasid_state->invalid = false;
661
662 /*
663 * Drop the reference to the mm_struct here. We rely on the
664 * mmu_notifier release call-back to inform us when the mm
665 * is going away.
666 */
667 mmput(mm);
668
669 return 0;
670
671 out_clear_state:
672 clear_pasid_state(dev_state, pasid);
673
674 out_unregister:
675 mmu_notifier_unregister(&pasid_state->mn, mm);
676 mmput(mm);
677
678 out_free:
679 free_pasid_state(pasid_state);
680
681 out:
682 put_device_state(dev_state);
683
684 return ret;
685 }
686 EXPORT_SYMBOL(amd_iommu_bind_pasid);
687
amd_iommu_unbind_pasid(struct pci_dev * pdev,u32 pasid)688 void amd_iommu_unbind_pasid(struct pci_dev *pdev, u32 pasid)
689 {
690 struct pasid_state *pasid_state;
691 struct device_state *dev_state;
692 u32 sbdf;
693
694 might_sleep();
695
696 if (!amd_iommu_v2_supported())
697 return;
698
699 sbdf = get_pci_sbdf_id(pdev);
700 dev_state = get_device_state(sbdf);
701 if (dev_state == NULL)
702 return;
703
704 if (pasid >= dev_state->max_pasids)
705 goto out;
706
707 pasid_state = get_pasid_state(dev_state, pasid);
708 if (pasid_state == NULL)
709 goto out;
710 /*
711 * Drop reference taken here. We are safe because we still hold
712 * the reference taken in the amd_iommu_bind_pasid function.
713 */
714 put_pasid_state(pasid_state);
715
716 /* Clear the pasid state so that the pasid can be re-used */
717 clear_pasid_state(dev_state, pasid_state->pasid);
718
719 /*
720 * Call mmu_notifier_unregister to drop our reference
721 * to pasid_state->mm
722 */
723 mmu_notifier_unregister(&pasid_state->mn, pasid_state->mm);
724
725 put_pasid_state_wait(pasid_state); /* Reference taken in
726 amd_iommu_bind_pasid */
727 out:
728 /* Drop reference taken in this function */
729 put_device_state(dev_state);
730
731 /* Drop reference taken in amd_iommu_bind_pasid */
732 put_device_state(dev_state);
733 }
734 EXPORT_SYMBOL(amd_iommu_unbind_pasid);
735
amd_iommu_init_device(struct pci_dev * pdev,int pasids)736 int amd_iommu_init_device(struct pci_dev *pdev, int pasids)
737 {
738 struct device_state *dev_state;
739 struct iommu_group *group;
740 unsigned long flags;
741 int ret, tmp;
742 u32 sbdf;
743
744 might_sleep();
745
746 /*
747 * When memory encryption is active the device is likely not in a
748 * direct-mapped domain. Forbid using IOMMUv2 functionality for now.
749 */
750 if (cc_platform_has(CC_ATTR_MEM_ENCRYPT))
751 return -ENODEV;
752
753 if (!amd_iommu_v2_supported())
754 return -ENODEV;
755
756 if (pasids <= 0 || pasids > (PASID_MASK + 1))
757 return -EINVAL;
758
759 sbdf = get_pci_sbdf_id(pdev);
760
761 dev_state = kzalloc(sizeof(*dev_state), GFP_KERNEL);
762 if (dev_state == NULL)
763 return -ENOMEM;
764
765 spin_lock_init(&dev_state->lock);
766 init_waitqueue_head(&dev_state->wq);
767 dev_state->pdev = pdev;
768 dev_state->sbdf = sbdf;
769
770 tmp = pasids;
771 for (dev_state->pasid_levels = 0; (tmp - 1) & ~0x1ff; tmp >>= 9)
772 dev_state->pasid_levels += 1;
773
774 atomic_set(&dev_state->count, 1);
775 dev_state->max_pasids = pasids;
776
777 ret = -ENOMEM;
778 dev_state->states = (void *)get_zeroed_page(GFP_KERNEL);
779 if (dev_state->states == NULL)
780 goto out_free_dev_state;
781
782 dev_state->domain = iommu_domain_alloc(&pci_bus_type);
783 if (dev_state->domain == NULL)
784 goto out_free_states;
785
786 /* See iommu_is_default_domain() */
787 dev_state->domain->type = IOMMU_DOMAIN_IDENTITY;
788 amd_iommu_domain_direct_map(dev_state->domain);
789
790 ret = amd_iommu_domain_enable_v2(dev_state->domain, pasids);
791 if (ret)
792 goto out_free_domain;
793
794 group = iommu_group_get(&pdev->dev);
795 if (!group) {
796 ret = -EINVAL;
797 goto out_free_domain;
798 }
799
800 ret = iommu_attach_group(dev_state->domain, group);
801 if (ret != 0)
802 goto out_drop_group;
803
804 iommu_group_put(group);
805
806 spin_lock_irqsave(&state_lock, flags);
807
808 if (__get_device_state(sbdf) != NULL) {
809 spin_unlock_irqrestore(&state_lock, flags);
810 ret = -EBUSY;
811 goto out_free_domain;
812 }
813
814 list_add_tail(&dev_state->list, &state_list);
815
816 spin_unlock_irqrestore(&state_lock, flags);
817
818 return 0;
819
820 out_drop_group:
821 iommu_group_put(group);
822
823 out_free_domain:
824 iommu_domain_free(dev_state->domain);
825
826 out_free_states:
827 free_page((unsigned long)dev_state->states);
828
829 out_free_dev_state:
830 kfree(dev_state);
831
832 return ret;
833 }
834 EXPORT_SYMBOL(amd_iommu_init_device);
835
amd_iommu_free_device(struct pci_dev * pdev)836 void amd_iommu_free_device(struct pci_dev *pdev)
837 {
838 struct device_state *dev_state;
839 unsigned long flags;
840 u32 sbdf;
841
842 if (!amd_iommu_v2_supported())
843 return;
844
845 sbdf = get_pci_sbdf_id(pdev);
846
847 spin_lock_irqsave(&state_lock, flags);
848
849 dev_state = __get_device_state(sbdf);
850 if (dev_state == NULL) {
851 spin_unlock_irqrestore(&state_lock, flags);
852 return;
853 }
854
855 list_del(&dev_state->list);
856
857 spin_unlock_irqrestore(&state_lock, flags);
858
859 put_device_state(dev_state);
860 free_device_state(dev_state);
861 }
862 EXPORT_SYMBOL(amd_iommu_free_device);
863
amd_iommu_set_invalid_ppr_cb(struct pci_dev * pdev,amd_iommu_invalid_ppr_cb cb)864 int amd_iommu_set_invalid_ppr_cb(struct pci_dev *pdev,
865 amd_iommu_invalid_ppr_cb cb)
866 {
867 struct device_state *dev_state;
868 unsigned long flags;
869 u32 sbdf;
870 int ret;
871
872 if (!amd_iommu_v2_supported())
873 return -ENODEV;
874
875 sbdf = get_pci_sbdf_id(pdev);
876
877 spin_lock_irqsave(&state_lock, flags);
878
879 ret = -EINVAL;
880 dev_state = __get_device_state(sbdf);
881 if (dev_state == NULL)
882 goto out_unlock;
883
884 dev_state->inv_ppr_cb = cb;
885
886 ret = 0;
887
888 out_unlock:
889 spin_unlock_irqrestore(&state_lock, flags);
890
891 return ret;
892 }
893 EXPORT_SYMBOL(amd_iommu_set_invalid_ppr_cb);
894
amd_iommu_set_invalidate_ctx_cb(struct pci_dev * pdev,amd_iommu_invalidate_ctx cb)895 int amd_iommu_set_invalidate_ctx_cb(struct pci_dev *pdev,
896 amd_iommu_invalidate_ctx cb)
897 {
898 struct device_state *dev_state;
899 unsigned long flags;
900 u32 sbdf;
901 int ret;
902
903 if (!amd_iommu_v2_supported())
904 return -ENODEV;
905
906 sbdf = get_pci_sbdf_id(pdev);
907
908 spin_lock_irqsave(&state_lock, flags);
909
910 ret = -EINVAL;
911 dev_state = __get_device_state(sbdf);
912 if (dev_state == NULL)
913 goto out_unlock;
914
915 dev_state->inv_ctx_cb = cb;
916
917 ret = 0;
918
919 out_unlock:
920 spin_unlock_irqrestore(&state_lock, flags);
921
922 return ret;
923 }
924 EXPORT_SYMBOL(amd_iommu_set_invalidate_ctx_cb);
925
amd_iommu_v2_init(void)926 static int __init amd_iommu_v2_init(void)
927 {
928 int ret;
929
930 if (!amd_iommu_v2_supported()) {
931 pr_info("AMD IOMMUv2 functionality not available on this system - This is not a bug.\n");
932 /*
933 * Load anyway to provide the symbols to other modules
934 * which may use AMD IOMMUv2 optionally.
935 */
936 return 0;
937 }
938
939 ret = -ENOMEM;
940 iommu_wq = alloc_workqueue("amd_iommu_v2", WQ_MEM_RECLAIM, 0);
941 if (iommu_wq == NULL)
942 goto out;
943
944 amd_iommu_register_ppr_notifier(&ppr_nb);
945
946 pr_info("AMD IOMMUv2 loaded and initialized\n");
947
948 return 0;
949
950 out:
951 return ret;
952 }
953
amd_iommu_v2_exit(void)954 static void __exit amd_iommu_v2_exit(void)
955 {
956 struct device_state *dev_state, *next;
957 unsigned long flags;
958 LIST_HEAD(freelist);
959
960 if (!amd_iommu_v2_supported())
961 return;
962
963 amd_iommu_unregister_ppr_notifier(&ppr_nb);
964
965 flush_workqueue(iommu_wq);
966
967 /*
968 * The loop below might call flush_workqueue(), so call
969 * destroy_workqueue() after it
970 */
971 spin_lock_irqsave(&state_lock, flags);
972
973 list_for_each_entry_safe(dev_state, next, &state_list, list) {
974 WARN_ON_ONCE(1);
975
976 put_device_state(dev_state);
977 list_del(&dev_state->list);
978 list_add_tail(&dev_state->list, &freelist);
979 }
980
981 spin_unlock_irqrestore(&state_lock, flags);
982
983 /*
984 * Since free_device_state waits on the count to be zero,
985 * we need to free dev_state outside the spinlock.
986 */
987 list_for_each_entry_safe(dev_state, next, &freelist, list) {
988 list_del(&dev_state->list);
989 free_device_state(dev_state);
990 }
991
992 destroy_workqueue(iommu_wq);
993 }
994
995 module_init(amd_iommu_v2_init);
996 module_exit(amd_iommu_v2_exit);
997
