i2c: tegra: Add stub runtime power management
[linux-2.6.git] / drivers / iommu / amd_iommu_v2.c
1 /*
2  * Copyright (C) 2010-2012 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/mmu_notifier.h>
20 #include <linux/amd-iommu.h>
21 #include <linux/mm_types.h>
22 #include <linux/profile.h>
23 #include <linux/module.h>
24 #include <linux/sched.h>
25 #include <linux/iommu.h>
26 #include <linux/wait.h>
27 #include <linux/pci.h>
28 #include <linux/gfp.h>
29
30 #include "amd_iommu_types.h"
31 #include "amd_iommu_proto.h"
32
33 MODULE_LICENSE("GPL v2");
34 MODULE_AUTHOR("Joerg Roedel <joerg.roedel@amd.com>");
35
36 #define MAX_DEVICES             0x10000
37 #define PRI_QUEUE_SIZE          512
38
39 struct pri_queue {
40         atomic_t inflight;
41         bool finish;
42         int status;
43 };
44
45 struct pasid_state {
46         struct list_head list;                  /* For global state-list */
47         atomic_t count;                         /* Reference count */
48         struct task_struct *task;               /* Task bound to this PASID */
49         struct mm_struct *mm;                   /* mm_struct for the faults */
50         struct mmu_notifier mn;                 /* mmu_otifier handle */
51         struct pri_queue pri[PRI_QUEUE_SIZE];   /* PRI tag states */
52         struct device_state *device_state;      /* Link to our device_state */
53         int pasid;                              /* PASID index */
54         spinlock_t lock;                        /* Protect pri_queues */
55         wait_queue_head_t wq;                   /* To wait for count == 0 */
56 };
57
58 struct device_state {
59         atomic_t count;
60         struct pci_dev *pdev;
61         struct pasid_state **states;
62         struct iommu_domain *domain;
63         int pasid_levels;
64         int max_pasids;
65         amd_iommu_invalid_ppr_cb inv_ppr_cb;
66         amd_iommu_invalidate_ctx inv_ctx_cb;
67         spinlock_t lock;
68         wait_queue_head_t wq;
69 };
70
71 struct fault {
72         struct work_struct work;
73         struct device_state *dev_state;
74         struct pasid_state *state;
75         struct mm_struct *mm;
76         u64 address;
77         u16 devid;
78         u16 pasid;
79         u16 tag;
80         u16 finish;
81         u16 flags;
82 };
83
84 struct device_state **state_table;
85 static spinlock_t state_lock;
86
87 /* List and lock for all pasid_states */
88 static LIST_HEAD(pasid_state_list);
89 static DEFINE_SPINLOCK(ps_lock);
90
91 static struct workqueue_struct *iommu_wq;
92
93 /*
94  * Empty page table - Used between
95  * mmu_notifier_invalidate_range_start and
96  * mmu_notifier_invalidate_range_end
97  */
98 static u64 *empty_page_table;
99
100 static void free_pasid_states(struct device_state *dev_state);
101 static void unbind_pasid(struct device_state *dev_state, int pasid);
102 static int task_exit(struct notifier_block *nb, unsigned long e, void *data);
103
104 static u16 device_id(struct pci_dev *pdev)
105 {
106         u16 devid;
107
108         devid = pdev->bus->number;
109         devid = (devid << 8) | pdev->devfn;
110
111         return devid;
112 }
113
114 static struct device_state *get_device_state(u16 devid)
115 {
116         struct device_state *dev_state;
117         unsigned long flags;
118
119         spin_lock_irqsave(&state_lock, flags);
120         dev_state = state_table[devid];
121         if (dev_state != NULL)
122                 atomic_inc(&dev_state->count);
123         spin_unlock_irqrestore(&state_lock, flags);
124
125         return dev_state;
126 }
127
128 static void free_device_state(struct device_state *dev_state)
129 {
130         /*
131          * First detach device from domain - No more PRI requests will arrive
132          * from that device after it is unbound from the IOMMUv2 domain.
133          */
134         iommu_detach_device(dev_state->domain, &dev_state->pdev->dev);
135
136         /* Everything is down now, free the IOMMUv2 domain */
137         iommu_domain_free(dev_state->domain);
138
139         /* Finally get rid of the device-state */
140         kfree(dev_state);
141 }
142
143 static void put_device_state(struct device_state *dev_state)
144 {
145         if (atomic_dec_and_test(&dev_state->count))
146                 wake_up(&dev_state->wq);
147 }
148
149 static void put_device_state_wait(struct device_state *dev_state)
150 {
151         DEFINE_WAIT(wait);
152
153         prepare_to_wait(&dev_state->wq, &wait, TASK_UNINTERRUPTIBLE);
154         if (!atomic_dec_and_test(&dev_state->count))
155                 schedule();
156         finish_wait(&dev_state->wq, &wait);
157
158         free_device_state(dev_state);
159 }
160
161 static struct notifier_block profile_nb = {
162         .notifier_call = task_exit,
163 };
164
165 static void link_pasid_state(struct pasid_state *pasid_state)
166 {
167         spin_lock(&ps_lock);
168         list_add_tail(&pasid_state->list, &pasid_state_list);
169         spin_unlock(&ps_lock);
170 }
171
172 static void __unlink_pasid_state(struct pasid_state *pasid_state)
173 {
174         list_del(&pasid_state->list);
175 }
176
177 static void unlink_pasid_state(struct pasid_state *pasid_state)
178 {
179         spin_lock(&ps_lock);
180         __unlink_pasid_state(pasid_state);
181         spin_unlock(&ps_lock);
182 }
183
184 /* Must be called under dev_state->lock */
185 static struct pasid_state **__get_pasid_state_ptr(struct device_state *dev_state,
186                                                   int pasid, bool alloc)
187 {
188         struct pasid_state **root, **ptr;
189         int level, index;
190
191         level = dev_state->pasid_levels;
192         root  = dev_state->states;
193
194         while (true) {
195
196                 index = (pasid >> (9 * level)) & 0x1ff;
197                 ptr   = &root[index];
198
199                 if (level == 0)
200                         break;
201
202                 if (*ptr == NULL) {
203                         if (!alloc)
204                                 return NULL;
205
206                         *ptr = (void *)get_zeroed_page(GFP_ATOMIC);
207                         if (*ptr == NULL)
208                                 return NULL;
209                 }
210
211                 root   = (struct pasid_state **)*ptr;
212                 level -= 1;
213         }
214
215         return ptr;
216 }
217
218 static int set_pasid_state(struct device_state *dev_state,
219                            struct pasid_state *pasid_state,
220                            int pasid)
221 {
222         struct pasid_state **ptr;
223         unsigned long flags;
224         int ret;
225
226         spin_lock_irqsave(&dev_state->lock, flags);
227         ptr = __get_pasid_state_ptr(dev_state, pasid, true);
228
229         ret = -ENOMEM;
230         if (ptr == NULL)
231                 goto out_unlock;
232
233         ret = -ENOMEM;
234         if (*ptr != NULL)
235                 goto out_unlock;
236
237         *ptr = pasid_state;
238
239         ret = 0;
240
241 out_unlock:
242         spin_unlock_irqrestore(&dev_state->lock, flags);
243
244         return ret;
245 }
246
247 static void clear_pasid_state(struct device_state *dev_state, int pasid)
248 {
249         struct pasid_state **ptr;
250         unsigned long flags;
251
252         spin_lock_irqsave(&dev_state->lock, flags);
253         ptr = __get_pasid_state_ptr(dev_state, pasid, true);
254
255         if (ptr == NULL)
256                 goto out_unlock;
257
258         *ptr = NULL;
259
260 out_unlock:
261         spin_unlock_irqrestore(&dev_state->lock, flags);
262 }
263
264 static struct pasid_state *get_pasid_state(struct device_state *dev_state,
265                                            int pasid)
266 {
267         struct pasid_state **ptr, *ret = NULL;
268         unsigned long flags;
269
270         spin_lock_irqsave(&dev_state->lock, flags);
271         ptr = __get_pasid_state_ptr(dev_state, pasid, false);
272
273         if (ptr == NULL)
274                 goto out_unlock;
275
276         ret = *ptr;
277         if (ret)
278                 atomic_inc(&ret->count);
279
280 out_unlock:
281         spin_unlock_irqrestore(&dev_state->lock, flags);
282
283         return ret;
284 }
285
286 static void free_pasid_state(struct pasid_state *pasid_state)
287 {
288         kfree(pasid_state);
289 }
290
291 static void put_pasid_state(struct pasid_state *pasid_state)
292 {
293         if (atomic_dec_and_test(&pasid_state->count)) {
294                 put_device_state(pasid_state->device_state);
295                 wake_up(&pasid_state->wq);
296         }
297 }
298
299 static void put_pasid_state_wait(struct pasid_state *pasid_state)
300 {
301         DEFINE_WAIT(wait);
302
303         prepare_to_wait(&pasid_state->wq, &wait, TASK_UNINTERRUPTIBLE);
304
305         if (atomic_dec_and_test(&pasid_state->count))
306                 put_device_state(pasid_state->device_state);
307         else
308                 schedule();
309
310         finish_wait(&pasid_state->wq, &wait);
311         mmput(pasid_state->mm);
312         free_pasid_state(pasid_state);
313 }
314
315 static void __unbind_pasid(struct pasid_state *pasid_state)
316 {
317         struct iommu_domain *domain;
318
319         domain = pasid_state->device_state->domain;
320
321         amd_iommu_domain_clear_gcr3(domain, pasid_state->pasid);
322         clear_pasid_state(pasid_state->device_state, pasid_state->pasid);
323
324         /* Make sure no more pending faults are in the queue */
325         flush_workqueue(iommu_wq);
326
327         mmu_notifier_unregister(&pasid_state->mn, pasid_state->mm);
328
329         put_pasid_state(pasid_state); /* Reference taken in bind() function */
330 }
331
332 static void unbind_pasid(struct device_state *dev_state, int pasid)
333 {
334         struct pasid_state *pasid_state;
335
336         pasid_state = get_pasid_state(dev_state, pasid);
337         if (pasid_state == NULL)
338                 return;
339
340         unlink_pasid_state(pasid_state);
341         __unbind_pasid(pasid_state);
342         put_pasid_state_wait(pasid_state); /* Reference taken in this function */
343 }
344
345 static void free_pasid_states_level1(struct pasid_state **tbl)
346 {
347         int i;
348
349         for (i = 0; i < 512; ++i) {
350                 if (tbl[i] == NULL)
351                         continue;
352
353                 free_page((unsigned long)tbl[i]);
354         }
355 }
356
357 static void free_pasid_states_level2(struct pasid_state **tbl)
358 {
359         struct pasid_state **ptr;
360         int i;
361
362         for (i = 0; i < 512; ++i) {
363                 if (tbl[i] == NULL)
364                         continue;
365
366                 ptr = (struct pasid_state **)tbl[i];
367                 free_pasid_states_level1(ptr);
368         }
369 }
370
371 static void free_pasid_states(struct device_state *dev_state)
372 {
373         struct pasid_state *pasid_state;
374         int i;
375
376         for (i = 0; i < dev_state->max_pasids; ++i) {
377                 pasid_state = get_pasid_state(dev_state, i);
378                 if (pasid_state == NULL)
379                         continue;
380
381                 put_pasid_state(pasid_state);
382                 unbind_pasid(dev_state, i);
383         }
384
385         if (dev_state->pasid_levels == 2)
386                 free_pasid_states_level2(dev_state->states);
387         else if (dev_state->pasid_levels == 1)
388                 free_pasid_states_level1(dev_state->states);
389         else if (dev_state->pasid_levels != 0)
390                 BUG();
391
392         free_page((unsigned long)dev_state->states);
393 }
394
395 static struct pasid_state *mn_to_state(struct mmu_notifier *mn)
396 {
397         return container_of(mn, struct pasid_state, mn);
398 }
399
400 static void __mn_flush_page(struct mmu_notifier *mn,
401                             unsigned long address)
402 {
403         struct pasid_state *pasid_state;
404         struct device_state *dev_state;
405
406         pasid_state = mn_to_state(mn);
407         dev_state   = pasid_state->device_state;
408
409         amd_iommu_flush_page(dev_state->domain, pasid_state->pasid, address);
410 }
411
412 static int mn_clear_flush_young(struct mmu_notifier *mn,
413                                 struct mm_struct *mm,
414                                 unsigned long address)
415 {
416         __mn_flush_page(mn, address);
417
418         return 0;
419 }
420
421 static void mn_change_pte(struct mmu_notifier *mn,
422                           struct mm_struct *mm,
423                           unsigned long address,
424                           pte_t pte)
425 {
426         __mn_flush_page(mn, address);
427 }
428
429 static void mn_invalidate_page(struct mmu_notifier *mn,
430                                struct mm_struct *mm,
431                                unsigned long address)
432 {
433         __mn_flush_page(mn, address);
434 }
435
436 static void mn_invalidate_range_start(struct mmu_notifier *mn,
437                                       struct mm_struct *mm,
438                                       unsigned long start, unsigned long end)
439 {
440         struct pasid_state *pasid_state;
441         struct device_state *dev_state;
442
443         pasid_state = mn_to_state(mn);
444         dev_state   = pasid_state->device_state;
445
446         amd_iommu_domain_set_gcr3(dev_state->domain, pasid_state->pasid,
447                                   __pa(empty_page_table));
448 }
449
450 static void mn_invalidate_range_end(struct mmu_notifier *mn,
451                                     struct mm_struct *mm,
452                                     unsigned long start, unsigned long end)
453 {
454         struct pasid_state *pasid_state;
455         struct device_state *dev_state;
456
457         pasid_state = mn_to_state(mn);
458         dev_state   = pasid_state->device_state;
459
460         amd_iommu_domain_set_gcr3(dev_state->domain, pasid_state->pasid,
461                                   __pa(pasid_state->mm->pgd));
462 }
463
464 static struct mmu_notifier_ops iommu_mn = {
465         .clear_flush_young      = mn_clear_flush_young,
466         .change_pte             = mn_change_pte,
467         .invalidate_page        = mn_invalidate_page,
468         .invalidate_range_start = mn_invalidate_range_start,
469         .invalidate_range_end   = mn_invalidate_range_end,
470 };
471
472 static void set_pri_tag_status(struct pasid_state *pasid_state,
473                                u16 tag, int status)
474 {
475         unsigned long flags;
476
477         spin_lock_irqsave(&pasid_state->lock, flags);
478         pasid_state->pri[tag].status = status;
479         spin_unlock_irqrestore(&pasid_state->lock, flags);
480 }
481
482 static void finish_pri_tag(struct device_state *dev_state,
483                            struct pasid_state *pasid_state,
484                            u16 tag)
485 {
486         unsigned long flags;
487
488         spin_lock_irqsave(&pasid_state->lock, flags);
489         if (atomic_dec_and_test(&pasid_state->pri[tag].inflight) &&
490             pasid_state->pri[tag].finish) {
491                 amd_iommu_complete_ppr(dev_state->pdev, pasid_state->pasid,
492                                        pasid_state->pri[tag].status, tag);
493                 pasid_state->pri[tag].finish = false;
494                 pasid_state->pri[tag].status = PPR_SUCCESS;
495         }
496         spin_unlock_irqrestore(&pasid_state->lock, flags);
497 }
498
499 static void do_fault(struct work_struct *work)
500 {
501         struct fault *fault = container_of(work, struct fault, work);
502         int npages, write;
503         struct page *page;
504
505         write = !!(fault->flags & PPR_FAULT_WRITE);
506
507         npages = get_user_pages(fault->state->task, fault->state->mm,
508                                 fault->address, 1, write, 0, &page, NULL);
509
510         if (npages == 1) {
511                 put_page(page);
512         } else if (fault->dev_state->inv_ppr_cb) {
513                 int status;
514
515                 status = fault->dev_state->inv_ppr_cb(fault->dev_state->pdev,
516                                                       fault->pasid,
517                                                       fault->address,
518                                                       fault->flags);
519                 switch (status) {
520                 case AMD_IOMMU_INV_PRI_RSP_SUCCESS:
521                         set_pri_tag_status(fault->state, fault->tag, PPR_SUCCESS);
522                         break;
523                 case AMD_IOMMU_INV_PRI_RSP_INVALID:
524                         set_pri_tag_status(fault->state, fault->tag, PPR_INVALID);
525                         break;
526                 case AMD_IOMMU_INV_PRI_RSP_FAIL:
527                         set_pri_tag_status(fault->state, fault->tag, PPR_FAILURE);
528                         break;
529                 default:
530                         BUG();
531                 }
532         } else {
533                 set_pri_tag_status(fault->state, fault->tag, PPR_INVALID);
534         }
535
536         finish_pri_tag(fault->dev_state, fault->state, fault->tag);
537
538         put_pasid_state(fault->state);
539
540         kfree(fault);
541 }
542
543 static int ppr_notifier(struct notifier_block *nb, unsigned long e, void *data)
544 {
545         struct amd_iommu_fault *iommu_fault;
546         struct pasid_state *pasid_state;
547         struct device_state *dev_state;
548         unsigned long flags;
549         struct fault *fault;
550         bool finish;
551         u16 tag;
552         int ret;
553
554         iommu_fault = data;
555         tag         = iommu_fault->tag & 0x1ff;
556         finish      = (iommu_fault->tag >> 9) & 1;
557
558         ret = NOTIFY_DONE;
559         dev_state = get_device_state(iommu_fault->device_id);
560         if (dev_state == NULL)
561                 goto out;
562
563         pasid_state = get_pasid_state(dev_state, iommu_fault->pasid);
564         if (pasid_state == NULL) {
565                 /* We know the device but not the PASID -> send INVALID */
566                 amd_iommu_complete_ppr(dev_state->pdev, iommu_fault->pasid,
567                                        PPR_INVALID, tag);
568                 goto out_drop_state;
569         }
570
571         spin_lock_irqsave(&pasid_state->lock, flags);
572         atomic_inc(&pasid_state->pri[tag].inflight);
573         if (finish)
574                 pasid_state->pri[tag].finish = true;
575         spin_unlock_irqrestore(&pasid_state->lock, flags);
576
577         fault = kzalloc(sizeof(*fault), GFP_ATOMIC);
578         if (fault == NULL) {
579                 /* We are OOM - send success and let the device re-fault */
580                 finish_pri_tag(dev_state, pasid_state, tag);
581                 goto out_drop_state;
582         }
583
584         fault->dev_state = dev_state;
585         fault->address   = iommu_fault->address;
586         fault->state     = pasid_state;
587         fault->tag       = tag;
588         fault->finish    = finish;
589         fault->flags     = iommu_fault->flags;
590         INIT_WORK(&fault->work, do_fault);
591
592         queue_work(iommu_wq, &fault->work);
593
594         ret = NOTIFY_OK;
595
596 out_drop_state:
597         put_device_state(dev_state);
598
599 out:
600         return ret;
601 }
602
603 static struct notifier_block ppr_nb = {
604         .notifier_call = ppr_notifier,
605 };
606
607 static int task_exit(struct notifier_block *nb, unsigned long e, void *data)
608 {
609         struct pasid_state *pasid_state;
610         struct task_struct *task;
611
612         task = data;
613
614         /*
615          * Using this notifier is a hack - but there is no other choice
616          * at the moment. What I really want is a sleeping notifier that
617          * is called when an MM goes down. But such a notifier doesn't
618          * exist yet. The notifier needs to sleep because it has to make
619          * sure that the device does not use the PASID and the address
620          * space anymore before it is destroyed. This includes waiting
621          * for pending PRI requests to pass the workqueue. The
622          * MMU-Notifiers would be a good fit, but they use RCU and so
623          * they are not allowed to sleep. Lets see how we can solve this
624          * in a more intelligent way in the future.
625          */
626 again:
627         spin_lock(&ps_lock);
628         list_for_each_entry(pasid_state, &pasid_state_list, list) {
629                 struct device_state *dev_state;
630                 int pasid;
631
632                 if (pasid_state->task != task)
633                         continue;
634
635                 /* Drop Lock and unbind */
636                 spin_unlock(&ps_lock);
637
638                 dev_state = pasid_state->device_state;
639                 pasid     = pasid_state->pasid;
640
641                 if (pasid_state->device_state->inv_ctx_cb)
642                         dev_state->inv_ctx_cb(dev_state->pdev, pasid);
643
644                 unbind_pasid(dev_state, pasid);
645
646                 /* Task may be in the list multiple times */
647                 goto again;
648         }
649         spin_unlock(&ps_lock);
650
651         return NOTIFY_OK;
652 }
653
654 int amd_iommu_bind_pasid(struct pci_dev *pdev, int pasid,
655                          struct task_struct *task)
656 {
657         struct pasid_state *pasid_state;
658         struct device_state *dev_state;
659         u16 devid;
660         int ret;
661
662         might_sleep();
663
664         if (!amd_iommu_v2_supported())
665                 return -ENODEV;
666
667         devid     = device_id(pdev);
668         dev_state = get_device_state(devid);
669
670         if (dev_state == NULL)
671                 return -EINVAL;
672
673         ret = -EINVAL;
674         if (pasid < 0 || pasid >= dev_state->max_pasids)
675                 goto out;
676
677         ret = -ENOMEM;
678         pasid_state = kzalloc(sizeof(*pasid_state), GFP_KERNEL);
679         if (pasid_state == NULL)
680                 goto out;
681
682         atomic_set(&pasid_state->count, 1);
683         init_waitqueue_head(&pasid_state->wq);
684         pasid_state->task         = task;
685         pasid_state->mm           = get_task_mm(task);
686         pasid_state->device_state = dev_state;
687         pasid_state->pasid        = pasid;
688         pasid_state->mn.ops       = &iommu_mn;
689
690         if (pasid_state->mm == NULL)
691                 goto out_free;
692
693         mmu_notifier_register(&pasid_state->mn, pasid_state->mm);
694
695         ret = set_pasid_state(dev_state, pasid_state, pasid);
696         if (ret)
697                 goto out_unregister;
698
699         ret = amd_iommu_domain_set_gcr3(dev_state->domain, pasid,
700                                         __pa(pasid_state->mm->pgd));
701         if (ret)
702                 goto out_clear_state;
703
704         link_pasid_state(pasid_state);
705
706         return 0;
707
708 out_clear_state:
709         clear_pasid_state(dev_state, pasid);
710
711 out_unregister:
712         mmu_notifier_unregister(&pasid_state->mn, pasid_state->mm);
713
714 out_free:
715         free_pasid_state(pasid_state);
716
717 out:
718         put_device_state(dev_state);
719
720         return ret;
721 }
722 EXPORT_SYMBOL(amd_iommu_bind_pasid);
723
724 void amd_iommu_unbind_pasid(struct pci_dev *pdev, int pasid)
725 {
726         struct device_state *dev_state;
727         u16 devid;
728
729         might_sleep();
730
731         if (!amd_iommu_v2_supported())
732                 return;
733
734         devid = device_id(pdev);
735         dev_state = get_device_state(devid);
736         if (dev_state == NULL)
737                 return;
738
739         if (pasid < 0 || pasid >= dev_state->max_pasids)
740                 goto out;
741
742         unbind_pasid(dev_state, pasid);
743
744 out:
745         put_device_state(dev_state);
746 }
747 EXPORT_SYMBOL(amd_iommu_unbind_pasid);
748
749 int amd_iommu_init_device(struct pci_dev *pdev, int pasids)
750 {
751         struct device_state *dev_state;
752         unsigned long flags;
753         int ret, tmp;
754         u16 devid;
755
756         might_sleep();
757
758         if (!amd_iommu_v2_supported())
759                 return -ENODEV;
760
761         if (pasids <= 0 || pasids > (PASID_MASK + 1))
762                 return -EINVAL;
763
764         devid = device_id(pdev);
765
766         dev_state = kzalloc(sizeof(*dev_state), GFP_KERNEL);
767         if (dev_state == NULL)
768                 return -ENOMEM;
769
770         spin_lock_init(&dev_state->lock);
771         init_waitqueue_head(&dev_state->wq);
772         dev_state->pdev = pdev;
773
774         tmp = pasids;
775         for (dev_state->pasid_levels = 0; (tmp - 1) & ~0x1ff; tmp >>= 9)
776                 dev_state->pasid_levels += 1;
777
778         atomic_set(&dev_state->count, 1);
779         dev_state->max_pasids = pasids;
780
781         ret = -ENOMEM;
782         dev_state->states = (void *)get_zeroed_page(GFP_KERNEL);
783         if (dev_state->states == NULL)
784                 goto out_free_dev_state;
785
786         dev_state->domain = iommu_domain_alloc(&pci_bus_type);
787         if (dev_state->domain == NULL)
788                 goto out_free_states;
789
790         amd_iommu_domain_direct_map(dev_state->domain);
791
792         ret = amd_iommu_domain_enable_v2(dev_state->domain, pasids);
793         if (ret)
794                 goto out_free_domain;
795
796         ret = iommu_attach_device(dev_state->domain, &pdev->dev);
797         if (ret != 0)
798                 goto out_free_domain;
799
800         spin_lock_irqsave(&state_lock, flags);
801
802         if (state_table[devid] != NULL) {
803                 spin_unlock_irqrestore(&state_lock, flags);
804                 ret = -EBUSY;
805                 goto out_free_domain;
806         }
807
808         state_table[devid] = dev_state;
809
810         spin_unlock_irqrestore(&state_lock, flags);
811
812         return 0;
813
814 out_free_domain:
815         iommu_domain_free(dev_state->domain);
816
817 out_free_states:
818         free_page((unsigned long)dev_state->states);
819
820 out_free_dev_state:
821         kfree(dev_state);
822
823         return ret;
824 }
825 EXPORT_SYMBOL(amd_iommu_init_device);
826
827 void amd_iommu_free_device(struct pci_dev *pdev)
828 {
829         struct device_state *dev_state;
830         unsigned long flags;
831         u16 devid;
832
833         if (!amd_iommu_v2_supported())
834                 return;
835
836         devid = device_id(pdev);
837
838         spin_lock_irqsave(&state_lock, flags);
839
840         dev_state = state_table[devid];
841         if (dev_state == NULL) {
842                 spin_unlock_irqrestore(&state_lock, flags);
843                 return;
844         }
845
846         state_table[devid] = NULL;
847
848         spin_unlock_irqrestore(&state_lock, flags);
849
850         /* Get rid of any remaining pasid states */
851         free_pasid_states(dev_state);
852
853         put_device_state_wait(dev_state);
854 }
855 EXPORT_SYMBOL(amd_iommu_free_device);
856
857 int amd_iommu_set_invalid_ppr_cb(struct pci_dev *pdev,
858                                  amd_iommu_invalid_ppr_cb cb)
859 {
860         struct device_state *dev_state;
861         unsigned long flags;
862         u16 devid;
863         int ret;
864
865         if (!amd_iommu_v2_supported())
866                 return -ENODEV;
867
868         devid = device_id(pdev);
869
870         spin_lock_irqsave(&state_lock, flags);
871
872         ret = -EINVAL;
873         dev_state = state_table[devid];
874         if (dev_state == NULL)
875                 goto out_unlock;
876
877         dev_state->inv_ppr_cb = cb;
878
879         ret = 0;
880
881 out_unlock:
882         spin_unlock_irqrestore(&state_lock, flags);
883
884         return ret;
885 }
886 EXPORT_SYMBOL(amd_iommu_set_invalid_ppr_cb);
887
888 int amd_iommu_set_invalidate_ctx_cb(struct pci_dev *pdev,
889                                     amd_iommu_invalidate_ctx cb)
890 {
891         struct device_state *dev_state;
892         unsigned long flags;
893         u16 devid;
894         int ret;
895
896         if (!amd_iommu_v2_supported())
897                 return -ENODEV;
898
899         devid = device_id(pdev);
900
901         spin_lock_irqsave(&state_lock, flags);
902
903         ret = -EINVAL;
904         dev_state = state_table[devid];
905         if (dev_state == NULL)
906                 goto out_unlock;
907
908         dev_state->inv_ctx_cb = cb;
909
910         ret = 0;
911
912 out_unlock:
913         spin_unlock_irqrestore(&state_lock, flags);
914
915         return ret;
916 }
917 EXPORT_SYMBOL(amd_iommu_set_invalidate_ctx_cb);
918
919 static int __init amd_iommu_v2_init(void)
920 {
921         size_t state_table_size;
922         int ret;
923
924         pr_info("AMD IOMMUv2 driver by Joerg Roedel <joerg.roedel@amd.com>");
925
926         spin_lock_init(&state_lock);
927
928         state_table_size = MAX_DEVICES * sizeof(struct device_state *);
929         state_table = (void *)__get_free_pages(GFP_KERNEL | __GFP_ZERO,
930                                                get_order(state_table_size));
931         if (state_table == NULL)
932                 return -ENOMEM;
933
934         ret = -ENOMEM;
935         iommu_wq = create_workqueue("amd_iommu_v2");
936         if (iommu_wq == NULL)
937                 goto out_free;
938
939         ret = -ENOMEM;
940         empty_page_table = (u64 *)get_zeroed_page(GFP_KERNEL);
941         if (empty_page_table == NULL)
942                 goto out_destroy_wq;
943
944         amd_iommu_register_ppr_notifier(&ppr_nb);
945         profile_event_register(PROFILE_TASK_EXIT, &profile_nb);
946
947         return 0;
948
949 out_destroy_wq:
950         destroy_workqueue(iommu_wq);
951
952 out_free:
953         free_pages((unsigned long)state_table, get_order(state_table_size));
954
955         return ret;
956 }
957
958 static void __exit amd_iommu_v2_exit(void)
959 {
960         struct device_state *dev_state;
961         size_t state_table_size;
962         int i;
963
964         profile_event_unregister(PROFILE_TASK_EXIT, &profile_nb);
965         amd_iommu_unregister_ppr_notifier(&ppr_nb);
966
967         flush_workqueue(iommu_wq);
968
969         /*
970          * The loop below might call flush_workqueue(), so call
971          * destroy_workqueue() after it
972          */
973         for (i = 0; i < MAX_DEVICES; ++i) {
974                 dev_state = get_device_state(i);
975
976                 if (dev_state == NULL)
977                         continue;
978
979                 WARN_ON_ONCE(1);
980
981                 put_device_state(dev_state);
982                 amd_iommu_free_device(dev_state->pdev);
983         }
984
985         destroy_workqueue(iommu_wq);
986
987         state_table_size = MAX_DEVICES * sizeof(struct device_state *);
988         free_pages((unsigned long)state_table, get_order(state_table_size));
989
990         free_page((unsigned long)empty_page_table);
991 }
992
993 module_init(amd_iommu_v2_init);
994 module_exit(amd_iommu_v2_exit);