2 * Copyright (C) 2010-2012 Advanced Micro Devices, Inc.
3 * Author: Joerg Roedel <jroedel@suse.de>
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.
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.
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
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/sched/mm.h>
26 #include <linux/iommu.h>
27 #include <linux/wait.h>
28 #include <linux/pci.h>
29 #include <linux/gfp.h>
31 #include "amd_iommu_types.h"
32 #include "amd_iommu_proto.h"
34 MODULE_LICENSE("GPL v2");
35 MODULE_AUTHOR("Joerg Roedel <jroedel@suse.de>");
37 #define MAX_DEVICES 0x10000
38 #define PRI_QUEUE_SIZE 512
47 struct list_head list; /* For global state-list */
48 atomic_t count; /* Reference count */
49 unsigned mmu_notifier_count; /* Counting nested mmu_notifier
51 struct mm_struct *mm; /* mm_struct for the faults */
52 struct mmu_notifier mn; /* mmu_notifier handle */
53 struct pri_queue pri[PRI_QUEUE_SIZE]; /* PRI tag states */
54 struct device_state *device_state; /* Link to our device_state */
55 int pasid; /* PASID index */
56 bool invalid; /* Used during setup and
57 teardown of the pasid */
58 spinlock_t lock; /* Protect pri_queues and
60 wait_queue_head_t wq; /* To wait for count == 0 */
64 struct list_head list;
68 struct pasid_state **states;
69 struct iommu_domain *domain;
72 amd_iommu_invalid_ppr_cb inv_ppr_cb;
73 amd_iommu_invalidate_ctx inv_ctx_cb;
79 struct work_struct work;
80 struct device_state *dev_state;
81 struct pasid_state *state;
91 static LIST_HEAD(state_list);
92 static spinlock_t state_lock;
94 static struct workqueue_struct *iommu_wq;
96 static void free_pasid_states(struct device_state *dev_state);
98 static u16 device_id(struct pci_dev *pdev)
102 devid = pdev->bus->number;
103 devid = (devid << 8) | pdev->devfn;
108 static struct device_state *__get_device_state(u16 devid)
110 struct device_state *dev_state;
112 list_for_each_entry(dev_state, &state_list, list) {
113 if (dev_state->devid == devid)
120 static struct device_state *get_device_state(u16 devid)
122 struct device_state *dev_state;
125 spin_lock_irqsave(&state_lock, flags);
126 dev_state = __get_device_state(devid);
127 if (dev_state != NULL)
128 atomic_inc(&dev_state->count);
129 spin_unlock_irqrestore(&state_lock, flags);
134 static void free_device_state(struct device_state *dev_state)
136 struct iommu_group *group;
139 * First detach device from domain - No more PRI requests will arrive
140 * from that device after it is unbound from the IOMMUv2 domain.
142 group = iommu_group_get(&dev_state->pdev->dev);
146 iommu_detach_group(dev_state->domain, group);
148 iommu_group_put(group);
150 /* Everything is down now, free the IOMMUv2 domain */
151 iommu_domain_free(dev_state->domain);
153 /* Finally get rid of the device-state */
157 static void put_device_state(struct device_state *dev_state)
159 if (atomic_dec_and_test(&dev_state->count))
160 wake_up(&dev_state->wq);
163 /* Must be called under dev_state->lock */
164 static struct pasid_state **__get_pasid_state_ptr(struct device_state *dev_state,
165 int pasid, bool alloc)
167 struct pasid_state **root, **ptr;
170 level = dev_state->pasid_levels;
171 root = dev_state->states;
175 index = (pasid >> (9 * level)) & 0x1ff;
185 *ptr = (void *)get_zeroed_page(GFP_ATOMIC);
190 root = (struct pasid_state **)*ptr;
197 static int set_pasid_state(struct device_state *dev_state,
198 struct pasid_state *pasid_state,
201 struct pasid_state **ptr;
205 spin_lock_irqsave(&dev_state->lock, flags);
206 ptr = __get_pasid_state_ptr(dev_state, pasid, true);
221 spin_unlock_irqrestore(&dev_state->lock, flags);
226 static void clear_pasid_state(struct device_state *dev_state, int pasid)
228 struct pasid_state **ptr;
231 spin_lock_irqsave(&dev_state->lock, flags);
232 ptr = __get_pasid_state_ptr(dev_state, pasid, true);
240 spin_unlock_irqrestore(&dev_state->lock, flags);
243 static struct pasid_state *get_pasid_state(struct device_state *dev_state,
246 struct pasid_state **ptr, *ret = NULL;
249 spin_lock_irqsave(&dev_state->lock, flags);
250 ptr = __get_pasid_state_ptr(dev_state, pasid, false);
257 atomic_inc(&ret->count);
260 spin_unlock_irqrestore(&dev_state->lock, flags);
265 static void free_pasid_state(struct pasid_state *pasid_state)
270 static void put_pasid_state(struct pasid_state *pasid_state)
272 if (atomic_dec_and_test(&pasid_state->count))
273 wake_up(&pasid_state->wq);
276 static void put_pasid_state_wait(struct pasid_state *pasid_state)
278 atomic_dec(&pasid_state->count);
279 wait_event(pasid_state->wq, !atomic_read(&pasid_state->count));
280 free_pasid_state(pasid_state);
283 static void unbind_pasid(struct pasid_state *pasid_state)
285 struct iommu_domain *domain;
287 domain = pasid_state->device_state->domain;
290 * Mark pasid_state as invalid, no more faults will we added to the
291 * work queue after this is visible everywhere.
293 pasid_state->invalid = true;
295 /* Make sure this is visible */
298 /* After this the device/pasid can't access the mm anymore */
299 amd_iommu_domain_clear_gcr3(domain, pasid_state->pasid);
301 /* Make sure no more pending faults are in the queue */
302 flush_workqueue(iommu_wq);
305 static void free_pasid_states_level1(struct pasid_state **tbl)
309 for (i = 0; i < 512; ++i) {
313 free_page((unsigned long)tbl[i]);
317 static void free_pasid_states_level2(struct pasid_state **tbl)
319 struct pasid_state **ptr;
322 for (i = 0; i < 512; ++i) {
326 ptr = (struct pasid_state **)tbl[i];
327 free_pasid_states_level1(ptr);
331 static void free_pasid_states(struct device_state *dev_state)
333 struct pasid_state *pasid_state;
336 for (i = 0; i < dev_state->max_pasids; ++i) {
337 pasid_state = get_pasid_state(dev_state, i);
338 if (pasid_state == NULL)
341 put_pasid_state(pasid_state);
344 * This will call the mn_release function and
347 mmu_notifier_unregister(&pasid_state->mn, pasid_state->mm);
349 put_pasid_state_wait(pasid_state); /* Reference taken in
350 amd_iommu_bind_pasid */
352 /* Drop reference taken in amd_iommu_bind_pasid */
353 put_device_state(dev_state);
356 if (dev_state->pasid_levels == 2)
357 free_pasid_states_level2(dev_state->states);
358 else if (dev_state->pasid_levels == 1)
359 free_pasid_states_level1(dev_state->states);
361 BUG_ON(dev_state->pasid_levels != 0);
363 free_page((unsigned long)dev_state->states);
366 static struct pasid_state *mn_to_state(struct mmu_notifier *mn)
368 return container_of(mn, struct pasid_state, mn);
371 static void __mn_flush_page(struct mmu_notifier *mn,
372 unsigned long address)
374 struct pasid_state *pasid_state;
375 struct device_state *dev_state;
377 pasid_state = mn_to_state(mn);
378 dev_state = pasid_state->device_state;
380 amd_iommu_flush_page(dev_state->domain, pasid_state->pasid, address);
383 static int mn_clear_flush_young(struct mmu_notifier *mn,
384 struct mm_struct *mm,
388 for (; start < end; start += PAGE_SIZE)
389 __mn_flush_page(mn, start);
394 static void mn_invalidate_range(struct mmu_notifier *mn,
395 struct mm_struct *mm,
396 unsigned long start, unsigned long end)
398 struct pasid_state *pasid_state;
399 struct device_state *dev_state;
401 pasid_state = mn_to_state(mn);
402 dev_state = pasid_state->device_state;
404 if ((start ^ (end - 1)) < PAGE_SIZE)
405 amd_iommu_flush_page(dev_state->domain, pasid_state->pasid,
408 amd_iommu_flush_tlb(dev_state->domain, pasid_state->pasid);
411 static void mn_release(struct mmu_notifier *mn, struct mm_struct *mm)
413 struct pasid_state *pasid_state;
414 struct device_state *dev_state;
419 pasid_state = mn_to_state(mn);
420 dev_state = pasid_state->device_state;
421 run_inv_ctx_cb = !pasid_state->invalid;
423 if (run_inv_ctx_cb && dev_state->inv_ctx_cb)
424 dev_state->inv_ctx_cb(dev_state->pdev, pasid_state->pasid);
426 unbind_pasid(pasid_state);
429 static const struct mmu_notifier_ops iommu_mn = {
430 .flags = MMU_INVALIDATE_DOES_NOT_BLOCK,
431 .release = mn_release,
432 .clear_flush_young = mn_clear_flush_young,
433 .invalidate_range = mn_invalidate_range,
436 static void set_pri_tag_status(struct pasid_state *pasid_state,
441 spin_lock_irqsave(&pasid_state->lock, flags);
442 pasid_state->pri[tag].status = status;
443 spin_unlock_irqrestore(&pasid_state->lock, flags);
446 static void finish_pri_tag(struct device_state *dev_state,
447 struct pasid_state *pasid_state,
452 spin_lock_irqsave(&pasid_state->lock, flags);
453 if (atomic_dec_and_test(&pasid_state->pri[tag].inflight) &&
454 pasid_state->pri[tag].finish) {
455 amd_iommu_complete_ppr(dev_state->pdev, pasid_state->pasid,
456 pasid_state->pri[tag].status, tag);
457 pasid_state->pri[tag].finish = false;
458 pasid_state->pri[tag].status = PPR_SUCCESS;
460 spin_unlock_irqrestore(&pasid_state->lock, flags);
463 static void handle_fault_error(struct fault *fault)
467 if (!fault->dev_state->inv_ppr_cb) {
468 set_pri_tag_status(fault->state, fault->tag, PPR_INVALID);
472 status = fault->dev_state->inv_ppr_cb(fault->dev_state->pdev,
477 case AMD_IOMMU_INV_PRI_RSP_SUCCESS:
478 set_pri_tag_status(fault->state, fault->tag, PPR_SUCCESS);
480 case AMD_IOMMU_INV_PRI_RSP_INVALID:
481 set_pri_tag_status(fault->state, fault->tag, PPR_INVALID);
483 case AMD_IOMMU_INV_PRI_RSP_FAIL:
484 set_pri_tag_status(fault->state, fault->tag, PPR_FAILURE);
491 static bool access_error(struct vm_area_struct *vma, struct fault *fault)
493 unsigned long requested = 0;
495 if (fault->flags & PPR_FAULT_EXEC)
496 requested |= VM_EXEC;
498 if (fault->flags & PPR_FAULT_READ)
499 requested |= VM_READ;
501 if (fault->flags & PPR_FAULT_WRITE)
502 requested |= VM_WRITE;
504 return (requested & ~vma->vm_flags) != 0;
507 static void do_fault(struct work_struct *work)
509 struct fault *fault = container_of(work, struct fault, work);
510 struct vm_area_struct *vma;
511 vm_fault_t ret = VM_FAULT_ERROR;
512 unsigned int flags = 0;
513 struct mm_struct *mm;
516 mm = fault->state->mm;
517 address = fault->address;
519 if (fault->flags & PPR_FAULT_USER)
520 flags |= FAULT_FLAG_USER;
521 if (fault->flags & PPR_FAULT_WRITE)
522 flags |= FAULT_FLAG_WRITE;
523 flags |= FAULT_FLAG_REMOTE;
525 down_read(&mm->mmap_sem);
526 vma = find_extend_vma(mm, address);
527 if (!vma || address < vma->vm_start)
528 /* failed to get a vma in the right range */
531 /* Check if we have the right permissions on the vma */
532 if (access_error(vma, fault))
535 ret = handle_mm_fault(vma, address, flags);
537 up_read(&mm->mmap_sem);
539 if (ret & VM_FAULT_ERROR)
540 /* failed to service fault */
541 handle_fault_error(fault);
543 finish_pri_tag(fault->dev_state, fault->state, fault->tag);
545 put_pasid_state(fault->state);
550 static int ppr_notifier(struct notifier_block *nb, unsigned long e, void *data)
552 struct amd_iommu_fault *iommu_fault;
553 struct pasid_state *pasid_state;
554 struct device_state *dev_state;
560 struct iommu_dev_data *dev_data;
561 struct pci_dev *pdev = NULL;
564 tag = iommu_fault->tag & 0x1ff;
565 finish = (iommu_fault->tag >> 9) & 1;
567 devid = iommu_fault->device_id;
568 pdev = pci_get_domain_bus_and_slot(0, PCI_BUS_NUM(devid),
572 dev_data = get_dev_data(&pdev->dev);
574 /* In kdump kernel pci dev is not initialized yet -> send INVALID */
576 if (translation_pre_enabled(amd_iommu_rlookup_table[devid])
577 && dev_data->defer_attach) {
578 amd_iommu_complete_ppr(pdev, iommu_fault->pasid,
583 dev_state = get_device_state(iommu_fault->device_id);
584 if (dev_state == NULL)
587 pasid_state = get_pasid_state(dev_state, iommu_fault->pasid);
588 if (pasid_state == NULL || pasid_state->invalid) {
589 /* We know the device but not the PASID -> send INVALID */
590 amd_iommu_complete_ppr(dev_state->pdev, iommu_fault->pasid,
595 spin_lock_irqsave(&pasid_state->lock, flags);
596 atomic_inc(&pasid_state->pri[tag].inflight);
598 pasid_state->pri[tag].finish = true;
599 spin_unlock_irqrestore(&pasid_state->lock, flags);
601 fault = kzalloc(sizeof(*fault), GFP_ATOMIC);
603 /* We are OOM - send success and let the device re-fault */
604 finish_pri_tag(dev_state, pasid_state, tag);
608 fault->dev_state = dev_state;
609 fault->address = iommu_fault->address;
610 fault->state = pasid_state;
612 fault->finish = finish;
613 fault->pasid = iommu_fault->pasid;
614 fault->flags = iommu_fault->flags;
615 INIT_WORK(&fault->work, do_fault);
617 queue_work(iommu_wq, &fault->work);
623 if (ret != NOTIFY_OK && pasid_state)
624 put_pasid_state(pasid_state);
626 put_device_state(dev_state);
633 static struct notifier_block ppr_nb = {
634 .notifier_call = ppr_notifier,
637 int amd_iommu_bind_pasid(struct pci_dev *pdev, int pasid,
638 struct task_struct *task)
640 struct pasid_state *pasid_state;
641 struct device_state *dev_state;
642 struct mm_struct *mm;
648 if (!amd_iommu_v2_supported())
651 devid = device_id(pdev);
652 dev_state = get_device_state(devid);
654 if (dev_state == NULL)
658 if (pasid < 0 || pasid >= dev_state->max_pasids)
662 pasid_state = kzalloc(sizeof(*pasid_state), GFP_KERNEL);
663 if (pasid_state == NULL)
667 atomic_set(&pasid_state->count, 1);
668 init_waitqueue_head(&pasid_state->wq);
669 spin_lock_init(&pasid_state->lock);
671 mm = get_task_mm(task);
672 pasid_state->mm = mm;
673 pasid_state->device_state = dev_state;
674 pasid_state->pasid = pasid;
675 pasid_state->invalid = true; /* Mark as valid only if we are
676 done with setting up the pasid */
677 pasid_state->mn.ops = &iommu_mn;
679 if (pasid_state->mm == NULL)
682 mmu_notifier_register(&pasid_state->mn, mm);
684 ret = set_pasid_state(dev_state, pasid_state, pasid);
688 ret = amd_iommu_domain_set_gcr3(dev_state->domain, pasid,
689 __pa(pasid_state->mm->pgd));
691 goto out_clear_state;
693 /* Now we are ready to handle faults */
694 pasid_state->invalid = false;
697 * Drop the reference to the mm_struct here. We rely on the
698 * mmu_notifier release call-back to inform us when the mm
706 clear_pasid_state(dev_state, pasid);
709 mmu_notifier_unregister(&pasid_state->mn, mm);
713 free_pasid_state(pasid_state);
716 put_device_state(dev_state);
720 EXPORT_SYMBOL(amd_iommu_bind_pasid);
722 void amd_iommu_unbind_pasid(struct pci_dev *pdev, int pasid)
724 struct pasid_state *pasid_state;
725 struct device_state *dev_state;
730 if (!amd_iommu_v2_supported())
733 devid = device_id(pdev);
734 dev_state = get_device_state(devid);
735 if (dev_state == NULL)
738 if (pasid < 0 || pasid >= dev_state->max_pasids)
741 pasid_state = get_pasid_state(dev_state, pasid);
742 if (pasid_state == NULL)
745 * Drop reference taken here. We are safe because we still hold
746 * the reference taken in the amd_iommu_bind_pasid function.
748 put_pasid_state(pasid_state);
750 /* Clear the pasid state so that the pasid can be re-used */
751 clear_pasid_state(dev_state, pasid_state->pasid);
754 * Call mmu_notifier_unregister to drop our reference
757 mmu_notifier_unregister(&pasid_state->mn, pasid_state->mm);
759 put_pasid_state_wait(pasid_state); /* Reference taken in
760 amd_iommu_bind_pasid */
762 /* Drop reference taken in this function */
763 put_device_state(dev_state);
765 /* Drop reference taken in amd_iommu_bind_pasid */
766 put_device_state(dev_state);
768 EXPORT_SYMBOL(amd_iommu_unbind_pasid);
770 int amd_iommu_init_device(struct pci_dev *pdev, int pasids)
772 struct device_state *dev_state;
773 struct iommu_group *group;
781 * When memory encryption is active the device is likely not in a
782 * direct-mapped domain. Forbid using IOMMUv2 functionality for now.
784 if (mem_encrypt_active())
787 if (!amd_iommu_v2_supported())
790 if (pasids <= 0 || pasids > (PASID_MASK + 1))
793 devid = device_id(pdev);
795 dev_state = kzalloc(sizeof(*dev_state), GFP_KERNEL);
796 if (dev_state == NULL)
799 spin_lock_init(&dev_state->lock);
800 init_waitqueue_head(&dev_state->wq);
801 dev_state->pdev = pdev;
802 dev_state->devid = devid;
805 for (dev_state->pasid_levels = 0; (tmp - 1) & ~0x1ff; tmp >>= 9)
806 dev_state->pasid_levels += 1;
808 atomic_set(&dev_state->count, 1);
809 dev_state->max_pasids = pasids;
812 dev_state->states = (void *)get_zeroed_page(GFP_KERNEL);
813 if (dev_state->states == NULL)
814 goto out_free_dev_state;
816 dev_state->domain = iommu_domain_alloc(&pci_bus_type);
817 if (dev_state->domain == NULL)
818 goto out_free_states;
820 amd_iommu_domain_direct_map(dev_state->domain);
822 ret = amd_iommu_domain_enable_v2(dev_state->domain, pasids);
824 goto out_free_domain;
826 group = iommu_group_get(&pdev->dev);
829 goto out_free_domain;
832 ret = iommu_attach_group(dev_state->domain, group);
836 iommu_group_put(group);
838 spin_lock_irqsave(&state_lock, flags);
840 if (__get_device_state(devid) != NULL) {
841 spin_unlock_irqrestore(&state_lock, flags);
843 goto out_free_domain;
846 list_add_tail(&dev_state->list, &state_list);
848 spin_unlock_irqrestore(&state_lock, flags);
853 iommu_group_put(group);
856 iommu_domain_free(dev_state->domain);
859 free_page((unsigned long)dev_state->states);
866 EXPORT_SYMBOL(amd_iommu_init_device);
868 void amd_iommu_free_device(struct pci_dev *pdev)
870 struct device_state *dev_state;
874 if (!amd_iommu_v2_supported())
877 devid = device_id(pdev);
879 spin_lock_irqsave(&state_lock, flags);
881 dev_state = __get_device_state(devid);
882 if (dev_state == NULL) {
883 spin_unlock_irqrestore(&state_lock, flags);
887 list_del(&dev_state->list);
889 spin_unlock_irqrestore(&state_lock, flags);
891 /* Get rid of any remaining pasid states */
892 free_pasid_states(dev_state);
894 put_device_state(dev_state);
896 * Wait until the last reference is dropped before freeing
899 wait_event(dev_state->wq, !atomic_read(&dev_state->count));
900 free_device_state(dev_state);
902 EXPORT_SYMBOL(amd_iommu_free_device);
904 int amd_iommu_set_invalid_ppr_cb(struct pci_dev *pdev,
905 amd_iommu_invalid_ppr_cb cb)
907 struct device_state *dev_state;
912 if (!amd_iommu_v2_supported())
915 devid = device_id(pdev);
917 spin_lock_irqsave(&state_lock, flags);
920 dev_state = __get_device_state(devid);
921 if (dev_state == NULL)
924 dev_state->inv_ppr_cb = cb;
929 spin_unlock_irqrestore(&state_lock, flags);
933 EXPORT_SYMBOL(amd_iommu_set_invalid_ppr_cb);
935 int amd_iommu_set_invalidate_ctx_cb(struct pci_dev *pdev,
936 amd_iommu_invalidate_ctx cb)
938 struct device_state *dev_state;
943 if (!amd_iommu_v2_supported())
946 devid = device_id(pdev);
948 spin_lock_irqsave(&state_lock, flags);
951 dev_state = __get_device_state(devid);
952 if (dev_state == NULL)
955 dev_state->inv_ctx_cb = cb;
960 spin_unlock_irqrestore(&state_lock, flags);
964 EXPORT_SYMBOL(amd_iommu_set_invalidate_ctx_cb);
966 static int __init amd_iommu_v2_init(void)
970 pr_info("AMD IOMMUv2 driver by Joerg Roedel <jroedel@suse.de>\n");
972 if (!amd_iommu_v2_supported()) {
973 pr_info("AMD IOMMUv2 functionality not available on this system\n");
975 * Load anyway to provide the symbols to other modules
976 * which may use AMD IOMMUv2 optionally.
981 spin_lock_init(&state_lock);
984 iommu_wq = alloc_workqueue("amd_iommu_v2", WQ_MEM_RECLAIM, 0);
985 if (iommu_wq == NULL)
988 amd_iommu_register_ppr_notifier(&ppr_nb);
996 static void __exit amd_iommu_v2_exit(void)
998 struct device_state *dev_state;
1001 if (!amd_iommu_v2_supported())
1004 amd_iommu_unregister_ppr_notifier(&ppr_nb);
1006 flush_workqueue(iommu_wq);
1009 * The loop below might call flush_workqueue(), so call
1010 * destroy_workqueue() after it
1012 for (i = 0; i < MAX_DEVICES; ++i) {
1013 dev_state = get_device_state(i);
1015 if (dev_state == NULL)
1020 put_device_state(dev_state);
1021 amd_iommu_free_device(dev_state->pdev);
1024 destroy_workqueue(iommu_wq);
1027 module_init(amd_iommu_v2_init);
1028 module_exit(amd_iommu_v2_exit);