c6c8bbea174851b613f4b14365af2314f489af5d
[pandora-kernel.git] / virt / kvm / kvm_main.c
1 /*
2  * Kernel-based Virtual Machine driver for Linux
3  *
4  * This module enables machines with Intel VT-x extensions to run virtual
5  * machines without emulation or binary translation.
6  *
7  * Copyright (C) 2006 Qumranet, Inc.
8  * Copyright 2010 Red Hat, Inc. and/or its affiliates.
9  *
10  * Authors:
11  *   Avi Kivity   <avi@qumranet.com>
12  *   Yaniv Kamay  <yaniv@qumranet.com>
13  *
14  * This work is licensed under the terms of the GNU GPL, version 2.  See
15  * the COPYING file in the top-level directory.
16  *
17  */
18
19 #include "iodev.h"
20
21 #include <linux/kvm_host.h>
22 #include <linux/kvm.h>
23 #include <linux/module.h>
24 #include <linux/errno.h>
25 #include <linux/percpu.h>
26 #include <linux/mm.h>
27 #include <linux/miscdevice.h>
28 #include <linux/vmalloc.h>
29 #include <linux/reboot.h>
30 #include <linux/debugfs.h>
31 #include <linux/highmem.h>
32 #include <linux/file.h>
33 #include <linux/syscore_ops.h>
34 #include <linux/cpu.h>
35 #include <linux/sched.h>
36 #include <linux/cpumask.h>
37 #include <linux/smp.h>
38 #include <linux/anon_inodes.h>
39 #include <linux/profile.h>
40 #include <linux/kvm_para.h>
41 #include <linux/pagemap.h>
42 #include <linux/mman.h>
43 #include <linux/swap.h>
44 #include <linux/bitops.h>
45 #include <linux/spinlock.h>
46 #include <linux/compat.h>
47 #include <linux/srcu.h>
48 #include <linux/hugetlb.h>
49 #include <linux/slab.h>
50 #include <linux/sort.h>
51 #include <linux/bsearch.h>
52
53 #include <asm/processor.h>
54 #include <asm/io.h>
55 #include <asm/uaccess.h>
56 #include <asm/pgtable.h>
57
58 #include "coalesced_mmio.h"
59 #include "async_pf.h"
60
61 #define CREATE_TRACE_POINTS
62 #include <trace/events/kvm.h>
63
64 MODULE_AUTHOR("Qumranet");
65 MODULE_LICENSE("GPL");
66
67 /*
68  * Ordering of locks:
69  *
70  *              kvm->lock --> kvm->slots_lock --> kvm->irq_lock
71  */
72
73 DEFINE_RAW_SPINLOCK(kvm_lock);
74 LIST_HEAD(vm_list);
75
76 static cpumask_var_t cpus_hardware_enabled;
77 static int kvm_usage_count = 0;
78 static atomic_t hardware_enable_failed;
79
80 struct kmem_cache *kvm_vcpu_cache;
81 EXPORT_SYMBOL_GPL(kvm_vcpu_cache);
82
83 static __read_mostly struct preempt_ops kvm_preempt_ops;
84
85 struct dentry *kvm_debugfs_dir;
86
87 static long kvm_vcpu_ioctl(struct file *file, unsigned int ioctl,
88                            unsigned long arg);
89 #ifdef CONFIG_COMPAT
90 static long kvm_vcpu_compat_ioctl(struct file *file, unsigned int ioctl,
91                                   unsigned long arg);
92 #endif
93 static int hardware_enable_all(void);
94 static void hardware_disable_all(void);
95
96 static void kvm_io_bus_destroy(struct kvm_io_bus *bus);
97
98 bool kvm_rebooting;
99 EXPORT_SYMBOL_GPL(kvm_rebooting);
100
101 static bool largepages_enabled = true;
102
103 bool kvm_is_mmio_pfn(pfn_t pfn)
104 {
105         if (pfn_valid(pfn)) {
106                 int reserved;
107                 struct page *tail = pfn_to_page(pfn);
108                 struct page *head = compound_trans_head(tail);
109                 reserved = PageReserved(head);
110                 if (head != tail) {
111                         /*
112                          * "head" is not a dangling pointer
113                          * (compound_trans_head takes care of that)
114                          * but the hugepage may have been splitted
115                          * from under us (and we may not hold a
116                          * reference count on the head page so it can
117                          * be reused before we run PageReferenced), so
118                          * we've to check PageTail before returning
119                          * what we just read.
120                          */
121                         smp_rmb();
122                         if (PageTail(tail))
123                                 return reserved;
124                 }
125                 return PageReserved(tail);
126         }
127
128         return true;
129 }
130
131 /*
132  * Switches to specified vcpu, until a matching vcpu_put()
133  */
134 int vcpu_load(struct kvm_vcpu *vcpu)
135 {
136         int cpu;
137
138         if (mutex_lock_killable(&vcpu->mutex))
139                 return -EINTR;
140         if (unlikely(vcpu->pid != current->pids[PIDTYPE_PID].pid)) {
141                 /* The thread running this VCPU changed. */
142                 struct pid *oldpid = vcpu->pid;
143                 struct pid *newpid = get_task_pid(current, PIDTYPE_PID);
144                 rcu_assign_pointer(vcpu->pid, newpid);
145                 synchronize_rcu();
146                 put_pid(oldpid);
147         }
148         cpu = get_cpu();
149         preempt_notifier_register(&vcpu->preempt_notifier);
150         kvm_arch_vcpu_load(vcpu, cpu);
151         put_cpu();
152         return 0;
153 }
154
155 void vcpu_put(struct kvm_vcpu *vcpu)
156 {
157         preempt_disable();
158         kvm_arch_vcpu_put(vcpu);
159         preempt_notifier_unregister(&vcpu->preempt_notifier);
160         preempt_enable();
161         mutex_unlock(&vcpu->mutex);
162 }
163
164 static void ack_flush(void *_completed)
165 {
166 }
167
168 static bool make_all_cpus_request(struct kvm *kvm, unsigned int req)
169 {
170         int i, cpu, me;
171         cpumask_var_t cpus;
172         bool called = true;
173         struct kvm_vcpu *vcpu;
174
175         zalloc_cpumask_var(&cpus, GFP_ATOMIC);
176
177         me = get_cpu();
178         kvm_for_each_vcpu(i, vcpu, kvm) {
179                 kvm_make_request(req, vcpu);
180                 cpu = vcpu->cpu;
181
182                 /* Set ->requests bit before we read ->mode */
183                 smp_mb();
184
185                 if (cpus != NULL && cpu != -1 && cpu != me &&
186                       kvm_vcpu_exiting_guest_mode(vcpu) != OUTSIDE_GUEST_MODE)
187                         cpumask_set_cpu(cpu, cpus);
188         }
189         if (unlikely(cpus == NULL))
190                 smp_call_function_many(cpu_online_mask, ack_flush, NULL, 1);
191         else if (!cpumask_empty(cpus))
192                 smp_call_function_many(cpus, ack_flush, NULL, 1);
193         else
194                 called = false;
195         put_cpu();
196         free_cpumask_var(cpus);
197         return called;
198 }
199
200 void kvm_flush_remote_tlbs(struct kvm *kvm)
201 {
202         long dirty_count = kvm->tlbs_dirty;
203
204         smp_mb();
205         if (make_all_cpus_request(kvm, KVM_REQ_TLB_FLUSH))
206                 ++kvm->stat.remote_tlb_flush;
207         cmpxchg(&kvm->tlbs_dirty, dirty_count, 0);
208 }
209
210 void kvm_reload_remote_mmus(struct kvm *kvm)
211 {
212         make_all_cpus_request(kvm, KVM_REQ_MMU_RELOAD);
213 }
214
215 void kvm_make_mclock_inprogress_request(struct kvm *kvm)
216 {
217         make_all_cpus_request(kvm, KVM_REQ_MCLOCK_INPROGRESS);
218 }
219
220 void kvm_make_scan_ioapic_request(struct kvm *kvm)
221 {
222         make_all_cpus_request(kvm, KVM_REQ_SCAN_IOAPIC);
223 }
224
225 int kvm_vcpu_init(struct kvm_vcpu *vcpu, struct kvm *kvm, unsigned id)
226 {
227         struct page *page;
228         int r;
229
230         mutex_init(&vcpu->mutex);
231         vcpu->cpu = -1;
232         vcpu->kvm = kvm;
233         vcpu->vcpu_id = id;
234         vcpu->pid = NULL;
235         init_waitqueue_head(&vcpu->wq);
236         kvm_async_pf_vcpu_init(vcpu);
237
238         page = alloc_page(GFP_KERNEL | __GFP_ZERO);
239         if (!page) {
240                 r = -ENOMEM;
241                 goto fail;
242         }
243         vcpu->run = page_address(page);
244
245         kvm_vcpu_set_in_spin_loop(vcpu, false);
246         kvm_vcpu_set_dy_eligible(vcpu, false);
247         vcpu->preempted = false;
248
249         r = kvm_arch_vcpu_init(vcpu);
250         if (r < 0)
251                 goto fail_free_run;
252         return 0;
253
254 fail_free_run:
255         free_page((unsigned long)vcpu->run);
256 fail:
257         return r;
258 }
259 EXPORT_SYMBOL_GPL(kvm_vcpu_init);
260
261 void kvm_vcpu_uninit(struct kvm_vcpu *vcpu)
262 {
263         put_pid(vcpu->pid);
264         kvm_arch_vcpu_uninit(vcpu);
265         free_page((unsigned long)vcpu->run);
266 }
267 EXPORT_SYMBOL_GPL(kvm_vcpu_uninit);
268
269 #if defined(CONFIG_MMU_NOTIFIER) && defined(KVM_ARCH_WANT_MMU_NOTIFIER)
270 static inline struct kvm *mmu_notifier_to_kvm(struct mmu_notifier *mn)
271 {
272         return container_of(mn, struct kvm, mmu_notifier);
273 }
274
275 static void kvm_mmu_notifier_invalidate_page(struct mmu_notifier *mn,
276                                              struct mm_struct *mm,
277                                              unsigned long address)
278 {
279         struct kvm *kvm = mmu_notifier_to_kvm(mn);
280         int need_tlb_flush, idx;
281
282         /*
283          * When ->invalidate_page runs, the linux pte has been zapped
284          * already but the page is still allocated until
285          * ->invalidate_page returns. So if we increase the sequence
286          * here the kvm page fault will notice if the spte can't be
287          * established because the page is going to be freed. If
288          * instead the kvm page fault establishes the spte before
289          * ->invalidate_page runs, kvm_unmap_hva will release it
290          * before returning.
291          *
292          * The sequence increase only need to be seen at spin_unlock
293          * time, and not at spin_lock time.
294          *
295          * Increasing the sequence after the spin_unlock would be
296          * unsafe because the kvm page fault could then establish the
297          * pte after kvm_unmap_hva returned, without noticing the page
298          * is going to be freed.
299          */
300         idx = srcu_read_lock(&kvm->srcu);
301         spin_lock(&kvm->mmu_lock);
302
303         kvm->mmu_notifier_seq++;
304         need_tlb_flush = kvm_unmap_hva(kvm, address) | kvm->tlbs_dirty;
305         /* we've to flush the tlb before the pages can be freed */
306         if (need_tlb_flush)
307                 kvm_flush_remote_tlbs(kvm);
308
309         spin_unlock(&kvm->mmu_lock);
310         srcu_read_unlock(&kvm->srcu, idx);
311 }
312
313 static void kvm_mmu_notifier_change_pte(struct mmu_notifier *mn,
314                                         struct mm_struct *mm,
315                                         unsigned long address,
316                                         pte_t pte)
317 {
318         struct kvm *kvm = mmu_notifier_to_kvm(mn);
319         int idx;
320
321         idx = srcu_read_lock(&kvm->srcu);
322         spin_lock(&kvm->mmu_lock);
323         kvm->mmu_notifier_seq++;
324         kvm_set_spte_hva(kvm, address, pte);
325         spin_unlock(&kvm->mmu_lock);
326         srcu_read_unlock(&kvm->srcu, idx);
327 }
328
329 static void kvm_mmu_notifier_invalidate_range_start(struct mmu_notifier *mn,
330                                                     struct mm_struct *mm,
331                                                     unsigned long start,
332                                                     unsigned long end)
333 {
334         struct kvm *kvm = mmu_notifier_to_kvm(mn);
335         int need_tlb_flush = 0, idx;
336
337         idx = srcu_read_lock(&kvm->srcu);
338         spin_lock(&kvm->mmu_lock);
339         /*
340          * The count increase must become visible at unlock time as no
341          * spte can be established without taking the mmu_lock and
342          * count is also read inside the mmu_lock critical section.
343          */
344         kvm->mmu_notifier_count++;
345         need_tlb_flush = kvm_unmap_hva_range(kvm, start, end);
346         need_tlb_flush |= kvm->tlbs_dirty;
347         /* we've to flush the tlb before the pages can be freed */
348         if (need_tlb_flush)
349                 kvm_flush_remote_tlbs(kvm);
350
351         spin_unlock(&kvm->mmu_lock);
352         srcu_read_unlock(&kvm->srcu, idx);
353 }
354
355 static void kvm_mmu_notifier_invalidate_range_end(struct mmu_notifier *mn,
356                                                   struct mm_struct *mm,
357                                                   unsigned long start,
358                                                   unsigned long end)
359 {
360         struct kvm *kvm = mmu_notifier_to_kvm(mn);
361
362         spin_lock(&kvm->mmu_lock);
363         /*
364          * This sequence increase will notify the kvm page fault that
365          * the page that is going to be mapped in the spte could have
366          * been freed.
367          */
368         kvm->mmu_notifier_seq++;
369         smp_wmb();
370         /*
371          * The above sequence increase must be visible before the
372          * below count decrease, which is ensured by the smp_wmb above
373          * in conjunction with the smp_rmb in mmu_notifier_retry().
374          */
375         kvm->mmu_notifier_count--;
376         spin_unlock(&kvm->mmu_lock);
377
378         BUG_ON(kvm->mmu_notifier_count < 0);
379 }
380
381 static int kvm_mmu_notifier_clear_flush_young(struct mmu_notifier *mn,
382                                               struct mm_struct *mm,
383                                               unsigned long address)
384 {
385         struct kvm *kvm = mmu_notifier_to_kvm(mn);
386         int young, idx;
387
388         idx = srcu_read_lock(&kvm->srcu);
389         spin_lock(&kvm->mmu_lock);
390
391         young = kvm_age_hva(kvm, address);
392         if (young)
393                 kvm_flush_remote_tlbs(kvm);
394
395         spin_unlock(&kvm->mmu_lock);
396         srcu_read_unlock(&kvm->srcu, idx);
397
398         return young;
399 }
400
401 static int kvm_mmu_notifier_test_young(struct mmu_notifier *mn,
402                                        struct mm_struct *mm,
403                                        unsigned long address)
404 {
405         struct kvm *kvm = mmu_notifier_to_kvm(mn);
406         int young, idx;
407
408         idx = srcu_read_lock(&kvm->srcu);
409         spin_lock(&kvm->mmu_lock);
410         young = kvm_test_age_hva(kvm, address);
411         spin_unlock(&kvm->mmu_lock);
412         srcu_read_unlock(&kvm->srcu, idx);
413
414         return young;
415 }
416
417 static void kvm_mmu_notifier_release(struct mmu_notifier *mn,
418                                      struct mm_struct *mm)
419 {
420         struct kvm *kvm = mmu_notifier_to_kvm(mn);
421         int idx;
422
423         idx = srcu_read_lock(&kvm->srcu);
424         kvm_arch_flush_shadow_all(kvm);
425         srcu_read_unlock(&kvm->srcu, idx);
426 }
427
428 static const struct mmu_notifier_ops kvm_mmu_notifier_ops = {
429         .invalidate_page        = kvm_mmu_notifier_invalidate_page,
430         .invalidate_range_start = kvm_mmu_notifier_invalidate_range_start,
431         .invalidate_range_end   = kvm_mmu_notifier_invalidate_range_end,
432         .clear_flush_young      = kvm_mmu_notifier_clear_flush_young,
433         .test_young             = kvm_mmu_notifier_test_young,
434         .change_pte             = kvm_mmu_notifier_change_pte,
435         .release                = kvm_mmu_notifier_release,
436 };
437
438 static int kvm_init_mmu_notifier(struct kvm *kvm)
439 {
440         kvm->mmu_notifier.ops = &kvm_mmu_notifier_ops;
441         return mmu_notifier_register(&kvm->mmu_notifier, current->mm);
442 }
443
444 #else  /* !(CONFIG_MMU_NOTIFIER && KVM_ARCH_WANT_MMU_NOTIFIER) */
445
446 static int kvm_init_mmu_notifier(struct kvm *kvm)
447 {
448         return 0;
449 }
450
451 #endif /* CONFIG_MMU_NOTIFIER && KVM_ARCH_WANT_MMU_NOTIFIER */
452
453 static void kvm_init_memslots_id(struct kvm *kvm)
454 {
455         int i;
456         struct kvm_memslots *slots = kvm->memslots;
457
458         for (i = 0; i < KVM_MEM_SLOTS_NUM; i++)
459                 slots->id_to_index[i] = slots->memslots[i].id = i;
460 }
461
462 static struct kvm *kvm_create_vm(unsigned long type)
463 {
464         int r, i;
465         struct kvm *kvm = kvm_arch_alloc_vm();
466
467         if (!kvm)
468                 return ERR_PTR(-ENOMEM);
469
470         r = kvm_arch_init_vm(kvm, type);
471         if (r)
472                 goto out_err_nodisable;
473
474         r = hardware_enable_all();
475         if (r)
476                 goto out_err_nodisable;
477
478 #ifdef CONFIG_HAVE_KVM_IRQCHIP
479         INIT_HLIST_HEAD(&kvm->mask_notifier_list);
480         INIT_HLIST_HEAD(&kvm->irq_ack_notifier_list);
481 #endif
482
483         BUILD_BUG_ON(KVM_MEM_SLOTS_NUM > SHRT_MAX);
484
485         r = -ENOMEM;
486         kvm->memslots = kzalloc(sizeof(struct kvm_memslots), GFP_KERNEL);
487         if (!kvm->memslots)
488                 goto out_err_nosrcu;
489         kvm_init_memslots_id(kvm);
490         if (init_srcu_struct(&kvm->srcu))
491                 goto out_err_nosrcu;
492         for (i = 0; i < KVM_NR_BUSES; i++) {
493                 kvm->buses[i] = kzalloc(sizeof(struct kvm_io_bus),
494                                         GFP_KERNEL);
495                 if (!kvm->buses[i])
496                         goto out_err;
497         }
498
499         spin_lock_init(&kvm->mmu_lock);
500         kvm->mm = current->mm;
501         atomic_inc(&kvm->mm->mm_count);
502         kvm_eventfd_init(kvm);
503         mutex_init(&kvm->lock);
504         mutex_init(&kvm->irq_lock);
505         mutex_init(&kvm->slots_lock);
506         atomic_set(&kvm->users_count, 1);
507         INIT_LIST_HEAD(&kvm->devices);
508
509         r = kvm_init_mmu_notifier(kvm);
510         if (r)
511                 goto out_err;
512
513         raw_spin_lock(&kvm_lock);
514         list_add(&kvm->vm_list, &vm_list);
515         raw_spin_unlock(&kvm_lock);
516
517         return kvm;
518
519 out_err:
520         cleanup_srcu_struct(&kvm->srcu);
521 out_err_nosrcu:
522         hardware_disable_all();
523 out_err_nodisable:
524         for (i = 0; i < KVM_NR_BUSES; i++)
525                 kfree(kvm->buses[i]);
526         kfree(kvm->memslots);
527         kvm_arch_free_vm(kvm);
528         return ERR_PTR(r);
529 }
530
531 /*
532  * Avoid using vmalloc for a small buffer.
533  * Should not be used when the size is statically known.
534  */
535 void *kvm_kvzalloc(unsigned long size)
536 {
537         if (size > PAGE_SIZE)
538                 return vzalloc(size);
539         else
540                 return kzalloc(size, GFP_KERNEL);
541 }
542
543 void kvm_kvfree(const void *addr)
544 {
545         if (is_vmalloc_addr(addr))
546                 vfree(addr);
547         else
548                 kfree(addr);
549 }
550
551 static void kvm_destroy_dirty_bitmap(struct kvm_memory_slot *memslot)
552 {
553         if (!memslot->dirty_bitmap)
554                 return;
555
556         kvm_kvfree(memslot->dirty_bitmap);
557         memslot->dirty_bitmap = NULL;
558 }
559
560 /*
561  * Free any memory in @free but not in @dont.
562  */
563 static void kvm_free_physmem_slot(struct kvm_memory_slot *free,
564                                   struct kvm_memory_slot *dont)
565 {
566         if (!dont || free->dirty_bitmap != dont->dirty_bitmap)
567                 kvm_destroy_dirty_bitmap(free);
568
569         kvm_arch_free_memslot(free, dont);
570
571         free->npages = 0;
572 }
573
574 void kvm_free_physmem(struct kvm *kvm)
575 {
576         struct kvm_memslots *slots = kvm->memslots;
577         struct kvm_memory_slot *memslot;
578
579         kvm_for_each_memslot(memslot, slots)
580                 kvm_free_physmem_slot(memslot, NULL);
581
582         kfree(kvm->memslots);
583 }
584
585 static void kvm_destroy_devices(struct kvm *kvm)
586 {
587         struct list_head *node, *tmp;
588
589         list_for_each_safe(node, tmp, &kvm->devices) {
590                 struct kvm_device *dev =
591                         list_entry(node, struct kvm_device, vm_node);
592
593                 list_del(node);
594                 dev->ops->destroy(dev);
595         }
596 }
597
598 static void kvm_destroy_vm(struct kvm *kvm)
599 {
600         int i;
601         struct mm_struct *mm = kvm->mm;
602
603         kvm_arch_sync_events(kvm);
604         raw_spin_lock(&kvm_lock);
605         list_del(&kvm->vm_list);
606         raw_spin_unlock(&kvm_lock);
607         kvm_free_irq_routing(kvm);
608         for (i = 0; i < KVM_NR_BUSES; i++)
609                 kvm_io_bus_destroy(kvm->buses[i]);
610         kvm_coalesced_mmio_free(kvm);
611 #if defined(CONFIG_MMU_NOTIFIER) && defined(KVM_ARCH_WANT_MMU_NOTIFIER)
612         mmu_notifier_unregister(&kvm->mmu_notifier, kvm->mm);
613 #else
614         kvm_arch_flush_shadow_all(kvm);
615 #endif
616         kvm_arch_destroy_vm(kvm);
617         kvm_destroy_devices(kvm);
618         kvm_free_physmem(kvm);
619         cleanup_srcu_struct(&kvm->srcu);
620         kvm_arch_free_vm(kvm);
621         hardware_disable_all();
622         mmdrop(mm);
623 }
624
625 void kvm_get_kvm(struct kvm *kvm)
626 {
627         atomic_inc(&kvm->users_count);
628 }
629 EXPORT_SYMBOL_GPL(kvm_get_kvm);
630
631 void kvm_put_kvm(struct kvm *kvm)
632 {
633         if (atomic_dec_and_test(&kvm->users_count))
634                 kvm_destroy_vm(kvm);
635 }
636 EXPORT_SYMBOL_GPL(kvm_put_kvm);
637
638
639 static int kvm_vm_release(struct inode *inode, struct file *filp)
640 {
641         struct kvm *kvm = filp->private_data;
642
643         kvm_irqfd_release(kvm);
644
645         kvm_put_kvm(kvm);
646         return 0;
647 }
648
649 /*
650  * Allocation size is twice as large as the actual dirty bitmap size.
651  * See x86's kvm_vm_ioctl_get_dirty_log() why this is needed.
652  */
653 static int kvm_create_dirty_bitmap(struct kvm_memory_slot *memslot)
654 {
655 #ifndef CONFIG_S390
656         unsigned long dirty_bytes = 2 * kvm_dirty_bitmap_bytes(memslot);
657
658         memslot->dirty_bitmap = kvm_kvzalloc(dirty_bytes);
659         if (!memslot->dirty_bitmap)
660                 return -ENOMEM;
661
662 #endif /* !CONFIG_S390 */
663         return 0;
664 }
665
666 static int cmp_memslot(const void *slot1, const void *slot2)
667 {
668         struct kvm_memory_slot *s1, *s2;
669
670         s1 = (struct kvm_memory_slot *)slot1;
671         s2 = (struct kvm_memory_slot *)slot2;
672
673         if (s1->npages < s2->npages)
674                 return 1;
675         if (s1->npages > s2->npages)
676                 return -1;
677
678         return 0;
679 }
680
681 /*
682  * Sort the memslots base on its size, so the larger slots
683  * will get better fit.
684  */
685 static void sort_memslots(struct kvm_memslots *slots)
686 {
687         int i;
688
689         sort(slots->memslots, KVM_MEM_SLOTS_NUM,
690               sizeof(struct kvm_memory_slot), cmp_memslot, NULL);
691
692         for (i = 0; i < KVM_MEM_SLOTS_NUM; i++)
693                 slots->id_to_index[slots->memslots[i].id] = i;
694 }
695
696 void update_memslots(struct kvm_memslots *slots, struct kvm_memory_slot *new,
697                      u64 last_generation)
698 {
699         if (new) {
700                 int id = new->id;
701                 struct kvm_memory_slot *old = id_to_memslot(slots, id);
702                 unsigned long npages = old->npages;
703
704                 *old = *new;
705                 if (new->npages != npages)
706                         sort_memslots(slots);
707         }
708
709         slots->generation = last_generation + 1;
710 }
711
712 static int check_memory_region_flags(struct kvm_userspace_memory_region *mem)
713 {
714         u32 valid_flags = KVM_MEM_LOG_DIRTY_PAGES;
715
716 #ifdef KVM_CAP_READONLY_MEM
717         valid_flags |= KVM_MEM_READONLY;
718 #endif
719
720         if (mem->flags & ~valid_flags)
721                 return -EINVAL;
722
723         return 0;
724 }
725
726 static struct kvm_memslots *install_new_memslots(struct kvm *kvm,
727                 struct kvm_memslots *slots, struct kvm_memory_slot *new)
728 {
729         struct kvm_memslots *old_memslots = kvm->memslots;
730
731         update_memslots(slots, new, kvm->memslots->generation);
732         rcu_assign_pointer(kvm->memslots, slots);
733         synchronize_srcu_expedited(&kvm->srcu);
734
735         kvm_arch_memslots_updated(kvm);
736
737         return old_memslots;
738 }
739
740 /*
741  * Allocate some memory and give it an address in the guest physical address
742  * space.
743  *
744  * Discontiguous memory is allowed, mostly for framebuffers.
745  *
746  * Must be called holding mmap_sem for write.
747  */
748 int __kvm_set_memory_region(struct kvm *kvm,
749                             struct kvm_userspace_memory_region *mem)
750 {
751         int r;
752         gfn_t base_gfn;
753         unsigned long npages;
754         struct kvm_memory_slot *slot;
755         struct kvm_memory_slot old, new;
756         struct kvm_memslots *slots = NULL, *old_memslots;
757         enum kvm_mr_change change;
758
759         r = check_memory_region_flags(mem);
760         if (r)
761                 goto out;
762
763         r = -EINVAL;
764         /* General sanity checks */
765         if (mem->memory_size & (PAGE_SIZE - 1))
766                 goto out;
767         if (mem->guest_phys_addr & (PAGE_SIZE - 1))
768                 goto out;
769         /* We can read the guest memory with __xxx_user() later on. */
770         if ((mem->slot < KVM_USER_MEM_SLOTS) &&
771             ((mem->userspace_addr & (PAGE_SIZE - 1)) ||
772              !access_ok(VERIFY_WRITE,
773                         (void __user *)(unsigned long)mem->userspace_addr,
774                         mem->memory_size)))
775                 goto out;
776         if (mem->slot >= KVM_MEM_SLOTS_NUM)
777                 goto out;
778         if (mem->guest_phys_addr + mem->memory_size < mem->guest_phys_addr)
779                 goto out;
780
781         slot = id_to_memslot(kvm->memslots, mem->slot);
782         base_gfn = mem->guest_phys_addr >> PAGE_SHIFT;
783         npages = mem->memory_size >> PAGE_SHIFT;
784
785         r = -EINVAL;
786         if (npages > KVM_MEM_MAX_NR_PAGES)
787                 goto out;
788
789         if (!npages)
790                 mem->flags &= ~KVM_MEM_LOG_DIRTY_PAGES;
791
792         new = old = *slot;
793
794         new.id = mem->slot;
795         new.base_gfn = base_gfn;
796         new.npages = npages;
797         new.flags = mem->flags;
798
799         r = -EINVAL;
800         if (npages) {
801                 if (!old.npages)
802                         change = KVM_MR_CREATE;
803                 else { /* Modify an existing slot. */
804                         if ((mem->userspace_addr != old.userspace_addr) ||
805                             (npages != old.npages) ||
806                             ((new.flags ^ old.flags) & KVM_MEM_READONLY))
807                                 goto out;
808
809                         if (base_gfn != old.base_gfn)
810                                 change = KVM_MR_MOVE;
811                         else if (new.flags != old.flags)
812                                 change = KVM_MR_FLAGS_ONLY;
813                         else { /* Nothing to change. */
814                                 r = 0;
815                                 goto out;
816                         }
817                 }
818         } else if (old.npages) {
819                 change = KVM_MR_DELETE;
820         } else /* Modify a non-existent slot: disallowed. */
821                 goto out;
822
823         if ((change == KVM_MR_CREATE) || (change == KVM_MR_MOVE)) {
824                 /* Check for overlaps */
825                 r = -EEXIST;
826                 kvm_for_each_memslot(slot, kvm->memslots) {
827                         if ((slot->id >= KVM_USER_MEM_SLOTS) ||
828                             (slot->id == mem->slot))
829                                 continue;
830                         if (!((base_gfn + npages <= slot->base_gfn) ||
831                               (base_gfn >= slot->base_gfn + slot->npages)))
832                                 goto out;
833                 }
834         }
835
836         /* Free page dirty bitmap if unneeded */
837         if (!(new.flags & KVM_MEM_LOG_DIRTY_PAGES))
838                 new.dirty_bitmap = NULL;
839
840         r = -ENOMEM;
841         if (change == KVM_MR_CREATE) {
842                 new.userspace_addr = mem->userspace_addr;
843
844                 if (kvm_arch_create_memslot(&new, npages))
845                         goto out_free;
846         }
847
848         /* Allocate page dirty bitmap if needed */
849         if ((new.flags & KVM_MEM_LOG_DIRTY_PAGES) && !new.dirty_bitmap) {
850                 if (kvm_create_dirty_bitmap(&new) < 0)
851                         goto out_free;
852         }
853
854         if ((change == KVM_MR_DELETE) || (change == KVM_MR_MOVE)) {
855                 r = -ENOMEM;
856                 slots = kmemdup(kvm->memslots, sizeof(struct kvm_memslots),
857                                 GFP_KERNEL);
858                 if (!slots)
859                         goto out_free;
860                 slot = id_to_memslot(slots, mem->slot);
861                 slot->flags |= KVM_MEMSLOT_INVALID;
862
863                 old_memslots = install_new_memslots(kvm, slots, NULL);
864
865                 /* slot was deleted or moved, clear iommu mapping */
866                 kvm_iommu_unmap_pages(kvm, &old);
867                 /* From this point no new shadow pages pointing to a deleted,
868                  * or moved, memslot will be created.
869                  *
870                  * validation of sp->gfn happens in:
871                  *      - gfn_to_hva (kvm_read_guest, gfn_to_pfn)
872                  *      - kvm_is_visible_gfn (mmu_check_roots)
873                  */
874                 kvm_arch_flush_shadow_memslot(kvm, slot);
875                 slots = old_memslots;
876         }
877
878         r = kvm_arch_prepare_memory_region(kvm, &new, mem, change);
879         if (r)
880                 goto out_slots;
881
882         r = -ENOMEM;
883         /*
884          * We can re-use the old_memslots from above, the only difference
885          * from the currently installed memslots is the invalid flag.  This
886          * will get overwritten by update_memslots anyway.
887          */
888         if (!slots) {
889                 slots = kmemdup(kvm->memslots, sizeof(struct kvm_memslots),
890                                 GFP_KERNEL);
891                 if (!slots)
892                         goto out_free;
893         }
894
895         /*
896          * IOMMU mapping:  New slots need to be mapped.  Old slots need to be
897          * un-mapped and re-mapped if their base changes.  Since base change
898          * unmapping is handled above with slot deletion, mapping alone is
899          * needed here.  Anything else the iommu might care about for existing
900          * slots (size changes, userspace addr changes and read-only flag
901          * changes) is disallowed above, so any other attribute changes getting
902          * here can be skipped.
903          */
904         if ((change == KVM_MR_CREATE) || (change == KVM_MR_MOVE)) {
905                 r = kvm_iommu_map_pages(kvm, &new);
906                 if (r)
907                         goto out_slots;
908         }
909
910         /* actual memory is freed via old in kvm_free_physmem_slot below */
911         if (change == KVM_MR_DELETE) {
912                 new.dirty_bitmap = NULL;
913                 memset(&new.arch, 0, sizeof(new.arch));
914         }
915
916         old_memslots = install_new_memslots(kvm, slots, &new);
917
918         kvm_arch_commit_memory_region(kvm, mem, &old, change);
919
920         kvm_free_physmem_slot(&old, &new);
921         kfree(old_memslots);
922
923         return 0;
924
925 out_slots:
926         kfree(slots);
927 out_free:
928         kvm_free_physmem_slot(&new, &old);
929 out:
930         return r;
931 }
932 EXPORT_SYMBOL_GPL(__kvm_set_memory_region);
933
934 int kvm_set_memory_region(struct kvm *kvm,
935                           struct kvm_userspace_memory_region *mem)
936 {
937         int r;
938
939         mutex_lock(&kvm->slots_lock);
940         r = __kvm_set_memory_region(kvm, mem);
941         mutex_unlock(&kvm->slots_lock);
942         return r;
943 }
944 EXPORT_SYMBOL_GPL(kvm_set_memory_region);
945
946 int kvm_vm_ioctl_set_memory_region(struct kvm *kvm,
947                                    struct kvm_userspace_memory_region *mem)
948 {
949         if (mem->slot >= KVM_USER_MEM_SLOTS)
950                 return -EINVAL;
951         return kvm_set_memory_region(kvm, mem);
952 }
953
954 int kvm_get_dirty_log(struct kvm *kvm,
955                         struct kvm_dirty_log *log, int *is_dirty)
956 {
957         struct kvm_memory_slot *memslot;
958         int r, i;
959         unsigned long n;
960         unsigned long any = 0;
961
962         r = -EINVAL;
963         if (log->slot >= KVM_USER_MEM_SLOTS)
964                 goto out;
965
966         memslot = id_to_memslot(kvm->memslots, log->slot);
967         r = -ENOENT;
968         if (!memslot->dirty_bitmap)
969                 goto out;
970
971         n = kvm_dirty_bitmap_bytes(memslot);
972
973         for (i = 0; !any && i < n/sizeof(long); ++i)
974                 any = memslot->dirty_bitmap[i];
975
976         r = -EFAULT;
977         if (copy_to_user(log->dirty_bitmap, memslot->dirty_bitmap, n))
978                 goto out;
979
980         if (any)
981                 *is_dirty = 1;
982
983         r = 0;
984 out:
985         return r;
986 }
987
988 bool kvm_largepages_enabled(void)
989 {
990         return largepages_enabled;
991 }
992
993 void kvm_disable_largepages(void)
994 {
995         largepages_enabled = false;
996 }
997 EXPORT_SYMBOL_GPL(kvm_disable_largepages);
998
999 struct kvm_memory_slot *gfn_to_memslot(struct kvm *kvm, gfn_t gfn)
1000 {
1001         return __gfn_to_memslot(kvm_memslots(kvm), gfn);
1002 }
1003 EXPORT_SYMBOL_GPL(gfn_to_memslot);
1004
1005 int kvm_is_visible_gfn(struct kvm *kvm, gfn_t gfn)
1006 {
1007         struct kvm_memory_slot *memslot = gfn_to_memslot(kvm, gfn);
1008
1009         if (!memslot || memslot->id >= KVM_USER_MEM_SLOTS ||
1010               memslot->flags & KVM_MEMSLOT_INVALID)
1011                 return 0;
1012
1013         return 1;
1014 }
1015 EXPORT_SYMBOL_GPL(kvm_is_visible_gfn);
1016
1017 unsigned long kvm_host_page_size(struct kvm *kvm, gfn_t gfn)
1018 {
1019         struct vm_area_struct *vma;
1020         unsigned long addr, size;
1021
1022         size = PAGE_SIZE;
1023
1024         addr = gfn_to_hva(kvm, gfn);
1025         if (kvm_is_error_hva(addr))
1026                 return PAGE_SIZE;
1027
1028         down_read(&current->mm->mmap_sem);
1029         vma = find_vma(current->mm, addr);
1030         if (!vma)
1031                 goto out;
1032
1033         size = vma_kernel_pagesize(vma);
1034
1035 out:
1036         up_read(&current->mm->mmap_sem);
1037
1038         return size;
1039 }
1040
1041 static bool memslot_is_readonly(struct kvm_memory_slot *slot)
1042 {
1043         return slot->flags & KVM_MEM_READONLY;
1044 }
1045
1046 static unsigned long __gfn_to_hva_many(struct kvm_memory_slot *slot, gfn_t gfn,
1047                                        gfn_t *nr_pages, bool write)
1048 {
1049         if (!slot || slot->flags & KVM_MEMSLOT_INVALID)
1050                 return KVM_HVA_ERR_BAD;
1051
1052         if (memslot_is_readonly(slot) && write)
1053                 return KVM_HVA_ERR_RO_BAD;
1054
1055         if (nr_pages)
1056                 *nr_pages = slot->npages - (gfn - slot->base_gfn);
1057
1058         return __gfn_to_hva_memslot(slot, gfn);
1059 }
1060
1061 static unsigned long gfn_to_hva_many(struct kvm_memory_slot *slot, gfn_t gfn,
1062                                      gfn_t *nr_pages)
1063 {
1064         return __gfn_to_hva_many(slot, gfn, nr_pages, true);
1065 }
1066
1067 unsigned long gfn_to_hva_memslot(struct kvm_memory_slot *slot,
1068                                  gfn_t gfn)
1069 {
1070         return gfn_to_hva_many(slot, gfn, NULL);
1071 }
1072 EXPORT_SYMBOL_GPL(gfn_to_hva_memslot);
1073
1074 unsigned long gfn_to_hva(struct kvm *kvm, gfn_t gfn)
1075 {
1076         return gfn_to_hva_many(gfn_to_memslot(kvm, gfn), gfn, NULL);
1077 }
1078 EXPORT_SYMBOL_GPL(gfn_to_hva);
1079
1080 /*
1081  * The hva returned by this function is only allowed to be read.
1082  * It should pair with kvm_read_hva() or kvm_read_hva_atomic().
1083  */
1084 static unsigned long gfn_to_hva_read(struct kvm *kvm, gfn_t gfn)
1085 {
1086         return __gfn_to_hva_many(gfn_to_memslot(kvm, gfn), gfn, NULL, false);
1087 }
1088
1089 static int kvm_read_hva(void *data, void __user *hva, int len)
1090 {
1091         return __copy_from_user(data, hva, len);
1092 }
1093
1094 static int kvm_read_hva_atomic(void *data, void __user *hva, int len)
1095 {
1096         return __copy_from_user_inatomic(data, hva, len);
1097 }
1098
1099 static int get_user_page_nowait(struct task_struct *tsk, struct mm_struct *mm,
1100         unsigned long start, int write, struct page **page)
1101 {
1102         int flags = FOLL_TOUCH | FOLL_NOWAIT | FOLL_HWPOISON | FOLL_GET;
1103
1104         if (write)
1105                 flags |= FOLL_WRITE;
1106
1107         return __get_user_pages(tsk, mm, start, 1, flags, page, NULL, NULL);
1108 }
1109
1110 static inline int check_user_page_hwpoison(unsigned long addr)
1111 {
1112         int rc, flags = FOLL_TOUCH | FOLL_HWPOISON | FOLL_WRITE;
1113
1114         rc = __get_user_pages(current, current->mm, addr, 1,
1115                               flags, NULL, NULL, NULL);
1116         return rc == -EHWPOISON;
1117 }
1118
1119 /*
1120  * The atomic path to get the writable pfn which will be stored in @pfn,
1121  * true indicates success, otherwise false is returned.
1122  */
1123 static bool hva_to_pfn_fast(unsigned long addr, bool atomic, bool *async,
1124                             bool write_fault, bool *writable, pfn_t *pfn)
1125 {
1126         struct page *page[1];
1127         int npages;
1128
1129         if (!(async || atomic))
1130                 return false;
1131
1132         /*
1133          * Fast pin a writable pfn only if it is a write fault request
1134          * or the caller allows to map a writable pfn for a read fault
1135          * request.
1136          */
1137         if (!(write_fault || writable))
1138                 return false;
1139
1140         npages = __get_user_pages_fast(addr, 1, 1, page);
1141         if (npages == 1) {
1142                 *pfn = page_to_pfn(page[0]);
1143
1144                 if (writable)
1145                         *writable = true;
1146                 return true;
1147         }
1148
1149         return false;
1150 }
1151
1152 /*
1153  * The slow path to get the pfn of the specified host virtual address,
1154  * 1 indicates success, -errno is returned if error is detected.
1155  */
1156 static int hva_to_pfn_slow(unsigned long addr, bool *async, bool write_fault,
1157                            bool *writable, pfn_t *pfn)
1158 {
1159         struct page *page[1];
1160         int npages = 0;
1161
1162         might_sleep();
1163
1164         if (writable)
1165                 *writable = write_fault;
1166
1167         if (async) {
1168                 down_read(&current->mm->mmap_sem);
1169                 npages = get_user_page_nowait(current, current->mm,
1170                                               addr, write_fault, page);
1171                 up_read(&current->mm->mmap_sem);
1172         } else
1173                 npages = get_user_pages_fast(addr, 1, write_fault,
1174                                              page);
1175         if (npages != 1)
1176                 return npages;
1177
1178         /* map read fault as writable if possible */
1179         if (unlikely(!write_fault) && writable) {
1180                 struct page *wpage[1];
1181
1182                 npages = __get_user_pages_fast(addr, 1, 1, wpage);
1183                 if (npages == 1) {
1184                         *writable = true;
1185                         put_page(page[0]);
1186                         page[0] = wpage[0];
1187                 }
1188
1189                 npages = 1;
1190         }
1191         *pfn = page_to_pfn(page[0]);
1192         return npages;
1193 }
1194
1195 static bool vma_is_valid(struct vm_area_struct *vma, bool write_fault)
1196 {
1197         if (unlikely(!(vma->vm_flags & VM_READ)))
1198                 return false;
1199
1200         if (write_fault && (unlikely(!(vma->vm_flags & VM_WRITE))))
1201                 return false;
1202
1203         return true;
1204 }
1205
1206 /*
1207  * Pin guest page in memory and return its pfn.
1208  * @addr: host virtual address which maps memory to the guest
1209  * @atomic: whether this function can sleep
1210  * @async: whether this function need to wait IO complete if the
1211  *         host page is not in the memory
1212  * @write_fault: whether we should get a writable host page
1213  * @writable: whether it allows to map a writable host page for !@write_fault
1214  *
1215  * The function will map a writable host page for these two cases:
1216  * 1): @write_fault = true
1217  * 2): @write_fault = false && @writable, @writable will tell the caller
1218  *     whether the mapping is writable.
1219  */
1220 static pfn_t hva_to_pfn(unsigned long addr, bool atomic, bool *async,
1221                         bool write_fault, bool *writable)
1222 {
1223         struct vm_area_struct *vma;
1224         pfn_t pfn = 0;
1225         int npages;
1226
1227         /* we can do it either atomically or asynchronously, not both */
1228         BUG_ON(atomic && async);
1229
1230         if (hva_to_pfn_fast(addr, atomic, async, write_fault, writable, &pfn))
1231                 return pfn;
1232
1233         if (atomic)
1234                 return KVM_PFN_ERR_FAULT;
1235
1236         npages = hva_to_pfn_slow(addr, async, write_fault, writable, &pfn);
1237         if (npages == 1)
1238                 return pfn;
1239
1240         down_read(&current->mm->mmap_sem);
1241         if (npages == -EHWPOISON ||
1242               (!async && check_user_page_hwpoison(addr))) {
1243                 pfn = KVM_PFN_ERR_HWPOISON;
1244                 goto exit;
1245         }
1246
1247         vma = find_vma_intersection(current->mm, addr, addr + 1);
1248
1249         if (vma == NULL)
1250                 pfn = KVM_PFN_ERR_FAULT;
1251         else if ((vma->vm_flags & VM_PFNMAP)) {
1252                 pfn = ((addr - vma->vm_start) >> PAGE_SHIFT) +
1253                         vma->vm_pgoff;
1254                 BUG_ON(!kvm_is_mmio_pfn(pfn));
1255         } else {
1256                 if (async && vma_is_valid(vma, write_fault))
1257                         *async = true;
1258                 pfn = KVM_PFN_ERR_FAULT;
1259         }
1260 exit:
1261         up_read(&current->mm->mmap_sem);
1262         return pfn;
1263 }
1264
1265 static pfn_t
1266 __gfn_to_pfn_memslot(struct kvm_memory_slot *slot, gfn_t gfn, bool atomic,
1267                      bool *async, bool write_fault, bool *writable)
1268 {
1269         unsigned long addr = __gfn_to_hva_many(slot, gfn, NULL, write_fault);
1270
1271         if (addr == KVM_HVA_ERR_RO_BAD)
1272                 return KVM_PFN_ERR_RO_FAULT;
1273
1274         if (kvm_is_error_hva(addr))
1275                 return KVM_PFN_NOSLOT;
1276
1277         /* Do not map writable pfn in the readonly memslot. */
1278         if (writable && memslot_is_readonly(slot)) {
1279                 *writable = false;
1280                 writable = NULL;
1281         }
1282
1283         return hva_to_pfn(addr, atomic, async, write_fault,
1284                           writable);
1285 }
1286
1287 static pfn_t __gfn_to_pfn(struct kvm *kvm, gfn_t gfn, bool atomic, bool *async,
1288                           bool write_fault, bool *writable)
1289 {
1290         struct kvm_memory_slot *slot;
1291
1292         if (async)
1293                 *async = false;
1294
1295         slot = gfn_to_memslot(kvm, gfn);
1296
1297         return __gfn_to_pfn_memslot(slot, gfn, atomic, async, write_fault,
1298                                     writable);
1299 }
1300
1301 pfn_t gfn_to_pfn_atomic(struct kvm *kvm, gfn_t gfn)
1302 {
1303         return __gfn_to_pfn(kvm, gfn, true, NULL, true, NULL);
1304 }
1305 EXPORT_SYMBOL_GPL(gfn_to_pfn_atomic);
1306
1307 pfn_t gfn_to_pfn_async(struct kvm *kvm, gfn_t gfn, bool *async,
1308                        bool write_fault, bool *writable)
1309 {
1310         return __gfn_to_pfn(kvm, gfn, false, async, write_fault, writable);
1311 }
1312 EXPORT_SYMBOL_GPL(gfn_to_pfn_async);
1313
1314 pfn_t gfn_to_pfn(struct kvm *kvm, gfn_t gfn)
1315 {
1316         return __gfn_to_pfn(kvm, gfn, false, NULL, true, NULL);
1317 }
1318 EXPORT_SYMBOL_GPL(gfn_to_pfn);
1319
1320 pfn_t gfn_to_pfn_prot(struct kvm *kvm, gfn_t gfn, bool write_fault,
1321                       bool *writable)
1322 {
1323         return __gfn_to_pfn(kvm, gfn, false, NULL, write_fault, writable);
1324 }
1325 EXPORT_SYMBOL_GPL(gfn_to_pfn_prot);
1326
1327 pfn_t gfn_to_pfn_memslot(struct kvm_memory_slot *slot, gfn_t gfn)
1328 {
1329         return __gfn_to_pfn_memslot(slot, gfn, false, NULL, true, NULL);
1330 }
1331
1332 pfn_t gfn_to_pfn_memslot_atomic(struct kvm_memory_slot *slot, gfn_t gfn)
1333 {
1334         return __gfn_to_pfn_memslot(slot, gfn, true, NULL, true, NULL);
1335 }
1336 EXPORT_SYMBOL_GPL(gfn_to_pfn_memslot_atomic);
1337
1338 int gfn_to_page_many_atomic(struct kvm *kvm, gfn_t gfn, struct page **pages,
1339                                                                   int nr_pages)
1340 {
1341         unsigned long addr;
1342         gfn_t entry;
1343
1344         addr = gfn_to_hva_many(gfn_to_memslot(kvm, gfn), gfn, &entry);
1345         if (kvm_is_error_hva(addr))
1346                 return -1;
1347
1348         if (entry < nr_pages)
1349                 return 0;
1350
1351         return __get_user_pages_fast(addr, nr_pages, 1, pages);
1352 }
1353 EXPORT_SYMBOL_GPL(gfn_to_page_many_atomic);
1354
1355 static struct page *kvm_pfn_to_page(pfn_t pfn)
1356 {
1357         if (is_error_noslot_pfn(pfn))
1358                 return KVM_ERR_PTR_BAD_PAGE;
1359
1360         if (kvm_is_mmio_pfn(pfn)) {
1361                 WARN_ON(1);
1362                 return KVM_ERR_PTR_BAD_PAGE;
1363         }
1364
1365         return pfn_to_page(pfn);
1366 }
1367
1368 struct page *gfn_to_page(struct kvm *kvm, gfn_t gfn)
1369 {
1370         pfn_t pfn;
1371
1372         pfn = gfn_to_pfn(kvm, gfn);
1373
1374         return kvm_pfn_to_page(pfn);
1375 }
1376
1377 EXPORT_SYMBOL_GPL(gfn_to_page);
1378
1379 void kvm_release_page_clean(struct page *page)
1380 {
1381         WARN_ON(is_error_page(page));
1382
1383         kvm_release_pfn_clean(page_to_pfn(page));
1384 }
1385 EXPORT_SYMBOL_GPL(kvm_release_page_clean);
1386
1387 void kvm_release_pfn_clean(pfn_t pfn)
1388 {
1389         if (!is_error_noslot_pfn(pfn) && !kvm_is_mmio_pfn(pfn))
1390                 put_page(pfn_to_page(pfn));
1391 }
1392 EXPORT_SYMBOL_GPL(kvm_release_pfn_clean);
1393
1394 void kvm_release_page_dirty(struct page *page)
1395 {
1396         WARN_ON(is_error_page(page));
1397
1398         kvm_release_pfn_dirty(page_to_pfn(page));
1399 }
1400 EXPORT_SYMBOL_GPL(kvm_release_page_dirty);
1401
1402 void kvm_release_pfn_dirty(pfn_t pfn)
1403 {
1404         kvm_set_pfn_dirty(pfn);
1405         kvm_release_pfn_clean(pfn);
1406 }
1407 EXPORT_SYMBOL_GPL(kvm_release_pfn_dirty);
1408
1409 void kvm_set_page_dirty(struct page *page)
1410 {
1411         kvm_set_pfn_dirty(page_to_pfn(page));
1412 }
1413 EXPORT_SYMBOL_GPL(kvm_set_page_dirty);
1414
1415 void kvm_set_pfn_dirty(pfn_t pfn)
1416 {
1417         if (!kvm_is_mmio_pfn(pfn)) {
1418                 struct page *page = pfn_to_page(pfn);
1419                 if (!PageReserved(page))
1420                         SetPageDirty(page);
1421         }
1422 }
1423 EXPORT_SYMBOL_GPL(kvm_set_pfn_dirty);
1424
1425 void kvm_set_pfn_accessed(pfn_t pfn)
1426 {
1427         if (!kvm_is_mmio_pfn(pfn))
1428                 mark_page_accessed(pfn_to_page(pfn));
1429 }
1430 EXPORT_SYMBOL_GPL(kvm_set_pfn_accessed);
1431
1432 void kvm_get_pfn(pfn_t pfn)
1433 {
1434         if (!kvm_is_mmio_pfn(pfn))
1435                 get_page(pfn_to_page(pfn));
1436 }
1437 EXPORT_SYMBOL_GPL(kvm_get_pfn);
1438
1439 static int next_segment(unsigned long len, int offset)
1440 {
1441         if (len > PAGE_SIZE - offset)
1442                 return PAGE_SIZE - offset;
1443         else
1444                 return len;
1445 }
1446
1447 int kvm_read_guest_page(struct kvm *kvm, gfn_t gfn, void *data, int offset,
1448                         int len)
1449 {
1450         int r;
1451         unsigned long addr;
1452
1453         addr = gfn_to_hva_read(kvm, gfn);
1454         if (kvm_is_error_hva(addr))
1455                 return -EFAULT;
1456         r = kvm_read_hva(data, (void __user *)addr + offset, len);
1457         if (r)
1458                 return -EFAULT;
1459         return 0;
1460 }
1461 EXPORT_SYMBOL_GPL(kvm_read_guest_page);
1462
1463 int kvm_read_guest(struct kvm *kvm, gpa_t gpa, void *data, unsigned long len)
1464 {
1465         gfn_t gfn = gpa >> PAGE_SHIFT;
1466         int seg;
1467         int offset = offset_in_page(gpa);
1468         int ret;
1469
1470         while ((seg = next_segment(len, offset)) != 0) {
1471                 ret = kvm_read_guest_page(kvm, gfn, data, offset, seg);
1472                 if (ret < 0)
1473                         return ret;
1474                 offset = 0;
1475                 len -= seg;
1476                 data += seg;
1477                 ++gfn;
1478         }
1479         return 0;
1480 }
1481 EXPORT_SYMBOL_GPL(kvm_read_guest);
1482
1483 int kvm_read_guest_atomic(struct kvm *kvm, gpa_t gpa, void *data,
1484                           unsigned long len)
1485 {
1486         int r;
1487         unsigned long addr;
1488         gfn_t gfn = gpa >> PAGE_SHIFT;
1489         int offset = offset_in_page(gpa);
1490
1491         addr = gfn_to_hva_read(kvm, gfn);
1492         if (kvm_is_error_hva(addr))
1493                 return -EFAULT;
1494         pagefault_disable();
1495         r = kvm_read_hva_atomic(data, (void __user *)addr + offset, len);
1496         pagefault_enable();
1497         if (r)
1498                 return -EFAULT;
1499         return 0;
1500 }
1501 EXPORT_SYMBOL(kvm_read_guest_atomic);
1502
1503 int kvm_write_guest_page(struct kvm *kvm, gfn_t gfn, const void *data,
1504                          int offset, int len)
1505 {
1506         int r;
1507         unsigned long addr;
1508
1509         addr = gfn_to_hva(kvm, gfn);
1510         if (kvm_is_error_hva(addr))
1511                 return -EFAULT;
1512         r = __copy_to_user((void __user *)addr + offset, data, len);
1513         if (r)
1514                 return -EFAULT;
1515         mark_page_dirty(kvm, gfn);
1516         return 0;
1517 }
1518 EXPORT_SYMBOL_GPL(kvm_write_guest_page);
1519
1520 int kvm_write_guest(struct kvm *kvm, gpa_t gpa, const void *data,
1521                     unsigned long len)
1522 {
1523         gfn_t gfn = gpa >> PAGE_SHIFT;
1524         int seg;
1525         int offset = offset_in_page(gpa);
1526         int ret;
1527
1528         while ((seg = next_segment(len, offset)) != 0) {
1529                 ret = kvm_write_guest_page(kvm, gfn, data, offset, seg);
1530                 if (ret < 0)
1531                         return ret;
1532                 offset = 0;
1533                 len -= seg;
1534                 data += seg;
1535                 ++gfn;
1536         }
1537         return 0;
1538 }
1539
1540 int kvm_gfn_to_hva_cache_init(struct kvm *kvm, struct gfn_to_hva_cache *ghc,
1541                               gpa_t gpa, unsigned long len)
1542 {
1543         struct kvm_memslots *slots = kvm_memslots(kvm);
1544         int offset = offset_in_page(gpa);
1545         gfn_t start_gfn = gpa >> PAGE_SHIFT;
1546         gfn_t end_gfn = (gpa + len - 1) >> PAGE_SHIFT;
1547         gfn_t nr_pages_needed = end_gfn - start_gfn + 1;
1548         gfn_t nr_pages_avail;
1549
1550         ghc->gpa = gpa;
1551         ghc->generation = slots->generation;
1552         ghc->len = len;
1553         ghc->memslot = gfn_to_memslot(kvm, start_gfn);
1554         ghc->hva = gfn_to_hva_many(ghc->memslot, start_gfn, &nr_pages_avail);
1555         if (!kvm_is_error_hva(ghc->hva) && nr_pages_avail >= nr_pages_needed) {
1556                 ghc->hva += offset;
1557         } else {
1558                 /*
1559                  * If the requested region crosses two memslots, we still
1560                  * verify that the entire region is valid here.
1561                  */
1562                 while (start_gfn <= end_gfn) {
1563                         ghc->memslot = gfn_to_memslot(kvm, start_gfn);
1564                         ghc->hva = gfn_to_hva_many(ghc->memslot, start_gfn,
1565                                                    &nr_pages_avail);
1566                         if (kvm_is_error_hva(ghc->hva))
1567                                 return -EFAULT;
1568                         start_gfn += nr_pages_avail;
1569                 }
1570                 /* Use the slow path for cross page reads and writes. */
1571                 ghc->memslot = NULL;
1572         }
1573         return 0;
1574 }
1575 EXPORT_SYMBOL_GPL(kvm_gfn_to_hva_cache_init);
1576
1577 int kvm_write_guest_cached(struct kvm *kvm, struct gfn_to_hva_cache *ghc,
1578                            void *data, unsigned long len)
1579 {
1580         struct kvm_memslots *slots = kvm_memslots(kvm);
1581         int r;
1582
1583         BUG_ON(len > ghc->len);
1584
1585         if (slots->generation != ghc->generation)
1586                 kvm_gfn_to_hva_cache_init(kvm, ghc, ghc->gpa, ghc->len);
1587
1588         if (unlikely(!ghc->memslot))
1589                 return kvm_write_guest(kvm, ghc->gpa, data, len);
1590
1591         if (kvm_is_error_hva(ghc->hva))
1592                 return -EFAULT;
1593
1594         r = __copy_to_user((void __user *)ghc->hva, data, len);
1595         if (r)
1596                 return -EFAULT;
1597         mark_page_dirty_in_slot(kvm, ghc->memslot, ghc->gpa >> PAGE_SHIFT);
1598
1599         return 0;
1600 }
1601 EXPORT_SYMBOL_GPL(kvm_write_guest_cached);
1602
1603 int kvm_read_guest_cached(struct kvm *kvm, struct gfn_to_hva_cache *ghc,
1604                            void *data, unsigned long len)
1605 {
1606         struct kvm_memslots *slots = kvm_memslots(kvm);
1607         int r;
1608
1609         BUG_ON(len > ghc->len);
1610
1611         if (slots->generation != ghc->generation)
1612                 kvm_gfn_to_hva_cache_init(kvm, ghc, ghc->gpa, ghc->len);
1613
1614         if (unlikely(!ghc->memslot))
1615                 return kvm_read_guest(kvm, ghc->gpa, data, len);
1616
1617         if (kvm_is_error_hva(ghc->hva))
1618                 return -EFAULT;
1619
1620         r = __copy_from_user(data, (void __user *)ghc->hva, len);
1621         if (r)
1622                 return -EFAULT;
1623
1624         return 0;
1625 }
1626 EXPORT_SYMBOL_GPL(kvm_read_guest_cached);
1627
1628 int kvm_clear_guest_page(struct kvm *kvm, gfn_t gfn, int offset, int len)
1629 {
1630         return kvm_write_guest_page(kvm, gfn, (const void *) empty_zero_page,
1631                                     offset, len);
1632 }
1633 EXPORT_SYMBOL_GPL(kvm_clear_guest_page);
1634
1635 int kvm_clear_guest(struct kvm *kvm, gpa_t gpa, unsigned long len)
1636 {
1637         gfn_t gfn = gpa >> PAGE_SHIFT;
1638         int seg;
1639         int offset = offset_in_page(gpa);
1640         int ret;
1641
1642         while ((seg = next_segment(len, offset)) != 0) {
1643                 ret = kvm_clear_guest_page(kvm, gfn, offset, seg);
1644                 if (ret < 0)
1645                         return ret;
1646                 offset = 0;
1647                 len -= seg;
1648                 ++gfn;
1649         }
1650         return 0;
1651 }
1652 EXPORT_SYMBOL_GPL(kvm_clear_guest);
1653
1654 void mark_page_dirty_in_slot(struct kvm *kvm, struct kvm_memory_slot *memslot,
1655                              gfn_t gfn)
1656 {
1657         if (memslot && memslot->dirty_bitmap) {
1658                 unsigned long rel_gfn = gfn - memslot->base_gfn;
1659
1660                 set_bit_le(rel_gfn, memslot->dirty_bitmap);
1661         }
1662 }
1663
1664 void mark_page_dirty(struct kvm *kvm, gfn_t gfn)
1665 {
1666         struct kvm_memory_slot *memslot;
1667
1668         memslot = gfn_to_memslot(kvm, gfn);
1669         mark_page_dirty_in_slot(kvm, memslot, gfn);
1670 }
1671
1672 /*
1673  * The vCPU has executed a HLT instruction with in-kernel mode enabled.
1674  */
1675 void kvm_vcpu_block(struct kvm_vcpu *vcpu)
1676 {
1677         DEFINE_WAIT(wait);
1678
1679         for (;;) {
1680                 prepare_to_wait(&vcpu->wq, &wait, TASK_INTERRUPTIBLE);
1681
1682                 if (kvm_arch_vcpu_runnable(vcpu)) {
1683                         kvm_make_request(KVM_REQ_UNHALT, vcpu);
1684                         break;
1685                 }
1686                 if (kvm_cpu_has_pending_timer(vcpu))
1687                         break;
1688                 if (signal_pending(current))
1689                         break;
1690
1691                 schedule();
1692         }
1693
1694         finish_wait(&vcpu->wq, &wait);
1695 }
1696
1697 #ifndef CONFIG_S390
1698 /*
1699  * Kick a sleeping VCPU, or a guest VCPU in guest mode, into host kernel mode.
1700  */
1701 void kvm_vcpu_kick(struct kvm_vcpu *vcpu)
1702 {
1703         int me;
1704         int cpu = vcpu->cpu;
1705         wait_queue_head_t *wqp;
1706
1707         wqp = kvm_arch_vcpu_wq(vcpu);
1708         if (waitqueue_active(wqp)) {
1709                 wake_up_interruptible(wqp);
1710                 ++vcpu->stat.halt_wakeup;
1711         }
1712
1713         me = get_cpu();
1714         if (cpu != me && (unsigned)cpu < nr_cpu_ids && cpu_online(cpu))
1715                 if (kvm_arch_vcpu_should_kick(vcpu))
1716                         smp_send_reschedule(cpu);
1717         put_cpu();
1718 }
1719 EXPORT_SYMBOL_GPL(kvm_vcpu_kick);
1720 #endif /* !CONFIG_S390 */
1721
1722 void kvm_resched(struct kvm_vcpu *vcpu)
1723 {
1724         if (!need_resched())
1725                 return;
1726         cond_resched();
1727 }
1728 EXPORT_SYMBOL_GPL(kvm_resched);
1729
1730 bool kvm_vcpu_yield_to(struct kvm_vcpu *target)
1731 {
1732         struct pid *pid;
1733         struct task_struct *task = NULL;
1734         bool ret = false;
1735
1736         rcu_read_lock();
1737         pid = rcu_dereference(target->pid);
1738         if (pid)
1739                 task = get_pid_task(target->pid, PIDTYPE_PID);
1740         rcu_read_unlock();
1741         if (!task)
1742                 return ret;
1743         if (task->flags & PF_VCPU) {
1744                 put_task_struct(task);
1745                 return ret;
1746         }
1747         ret = yield_to(task, 1);
1748         put_task_struct(task);
1749
1750         return ret;
1751 }
1752 EXPORT_SYMBOL_GPL(kvm_vcpu_yield_to);
1753
1754 #ifdef CONFIG_HAVE_KVM_CPU_RELAX_INTERCEPT
1755 /*
1756  * Helper that checks whether a VCPU is eligible for directed yield.
1757  * Most eligible candidate to yield is decided by following heuristics:
1758  *
1759  *  (a) VCPU which has not done pl-exit or cpu relax intercepted recently
1760  *  (preempted lock holder), indicated by @in_spin_loop.
1761  *  Set at the beiginning and cleared at the end of interception/PLE handler.
1762  *
1763  *  (b) VCPU which has done pl-exit/ cpu relax intercepted but did not get
1764  *  chance last time (mostly it has become eligible now since we have probably
1765  *  yielded to lockholder in last iteration. This is done by toggling
1766  *  @dy_eligible each time a VCPU checked for eligibility.)
1767  *
1768  *  Yielding to a recently pl-exited/cpu relax intercepted VCPU before yielding
1769  *  to preempted lock-holder could result in wrong VCPU selection and CPU
1770  *  burning. Giving priority for a potential lock-holder increases lock
1771  *  progress.
1772  *
1773  *  Since algorithm is based on heuristics, accessing another VCPU data without
1774  *  locking does not harm. It may result in trying to yield to  same VCPU, fail
1775  *  and continue with next VCPU and so on.
1776  */
1777 bool kvm_vcpu_eligible_for_directed_yield(struct kvm_vcpu *vcpu)
1778 {
1779         bool eligible;
1780
1781         eligible = !vcpu->spin_loop.in_spin_loop ||
1782                         (vcpu->spin_loop.in_spin_loop &&
1783                          vcpu->spin_loop.dy_eligible);
1784
1785         if (vcpu->spin_loop.in_spin_loop)
1786                 kvm_vcpu_set_dy_eligible(vcpu, !vcpu->spin_loop.dy_eligible);
1787
1788         return eligible;
1789 }
1790 #endif
1791
1792 void kvm_vcpu_on_spin(struct kvm_vcpu *me)
1793 {
1794         struct kvm *kvm = me->kvm;
1795         struct kvm_vcpu *vcpu;
1796         int last_boosted_vcpu = me->kvm->last_boosted_vcpu;
1797         int yielded = 0;
1798         int try = 3;
1799         int pass;
1800         int i;
1801
1802         kvm_vcpu_set_in_spin_loop(me, true);
1803         /*
1804          * We boost the priority of a VCPU that is runnable but not
1805          * currently running, because it got preempted by something
1806          * else and called schedule in __vcpu_run.  Hopefully that
1807          * VCPU is holding the lock that we need and will release it.
1808          * We approximate round-robin by starting at the last boosted VCPU.
1809          */
1810         for (pass = 0; pass < 2 && !yielded && try; pass++) {
1811                 kvm_for_each_vcpu(i, vcpu, kvm) {
1812                         if (!pass && i <= last_boosted_vcpu) {
1813                                 i = last_boosted_vcpu;
1814                                 continue;
1815                         } else if (pass && i > last_boosted_vcpu)
1816                                 break;
1817                         if (!ACCESS_ONCE(vcpu->preempted))
1818                                 continue;
1819                         if (vcpu == me)
1820                                 continue;
1821                         if (waitqueue_active(&vcpu->wq))
1822                                 continue;
1823                         if (!kvm_vcpu_eligible_for_directed_yield(vcpu))
1824                                 continue;
1825
1826                         yielded = kvm_vcpu_yield_to(vcpu);
1827                         if (yielded > 0) {
1828                                 kvm->last_boosted_vcpu = i;
1829                                 break;
1830                         } else if (yielded < 0) {
1831                                 try--;
1832                                 if (!try)
1833                                         break;
1834                         }
1835                 }
1836         }
1837         kvm_vcpu_set_in_spin_loop(me, false);
1838
1839         /* Ensure vcpu is not eligible during next spinloop */
1840         kvm_vcpu_set_dy_eligible(me, false);
1841 }
1842 EXPORT_SYMBOL_GPL(kvm_vcpu_on_spin);
1843
1844 static int kvm_vcpu_fault(struct vm_area_struct *vma, struct vm_fault *vmf)
1845 {
1846         struct kvm_vcpu *vcpu = vma->vm_file->private_data;
1847         struct page *page;
1848
1849         if (vmf->pgoff == 0)
1850                 page = virt_to_page(vcpu->run);
1851 #ifdef CONFIG_X86
1852         else if (vmf->pgoff == KVM_PIO_PAGE_OFFSET)
1853                 page = virt_to_page(vcpu->arch.pio_data);
1854 #endif
1855 #ifdef KVM_COALESCED_MMIO_PAGE_OFFSET
1856         else if (vmf->pgoff == KVM_COALESCED_MMIO_PAGE_OFFSET)
1857                 page = virt_to_page(vcpu->kvm->coalesced_mmio_ring);
1858 #endif
1859         else
1860                 return kvm_arch_vcpu_fault(vcpu, vmf);
1861         get_page(page);
1862         vmf->page = page;
1863         return 0;
1864 }
1865
1866 static const struct vm_operations_struct kvm_vcpu_vm_ops = {
1867         .fault = kvm_vcpu_fault,
1868 };
1869
1870 static int kvm_vcpu_mmap(struct file *file, struct vm_area_struct *vma)
1871 {
1872         vma->vm_ops = &kvm_vcpu_vm_ops;
1873         return 0;
1874 }
1875
1876 static int kvm_vcpu_release(struct inode *inode, struct file *filp)
1877 {
1878         struct kvm_vcpu *vcpu = filp->private_data;
1879
1880         kvm_put_kvm(vcpu->kvm);
1881         return 0;
1882 }
1883
1884 static struct file_operations kvm_vcpu_fops = {
1885         .release        = kvm_vcpu_release,
1886         .unlocked_ioctl = kvm_vcpu_ioctl,
1887 #ifdef CONFIG_COMPAT
1888         .compat_ioctl   = kvm_vcpu_compat_ioctl,
1889 #endif
1890         .mmap           = kvm_vcpu_mmap,
1891         .llseek         = noop_llseek,
1892 };
1893
1894 /*
1895  * Allocates an inode for the vcpu.
1896  */
1897 static int create_vcpu_fd(struct kvm_vcpu *vcpu)
1898 {
1899         return anon_inode_getfd("kvm-vcpu", &kvm_vcpu_fops, vcpu, O_RDWR);
1900 }
1901
1902 /*
1903  * Creates some virtual cpus.  Good luck creating more than one.
1904  */
1905 static int kvm_vm_ioctl_create_vcpu(struct kvm *kvm, u32 id)
1906 {
1907         int r;
1908         struct kvm_vcpu *vcpu, *v;
1909
1910         vcpu = kvm_arch_vcpu_create(kvm, id);
1911         if (IS_ERR(vcpu))
1912                 return PTR_ERR(vcpu);
1913
1914         preempt_notifier_init(&vcpu->preempt_notifier, &kvm_preempt_ops);
1915
1916         r = kvm_arch_vcpu_setup(vcpu);
1917         if (r)
1918                 goto vcpu_destroy;
1919
1920         mutex_lock(&kvm->lock);
1921         if (!kvm_vcpu_compatible(vcpu)) {
1922                 r = -EINVAL;
1923                 goto unlock_vcpu_destroy;
1924         }
1925         if (atomic_read(&kvm->online_vcpus) == KVM_MAX_VCPUS) {
1926                 r = -EINVAL;
1927                 goto unlock_vcpu_destroy;
1928         }
1929
1930         kvm_for_each_vcpu(r, v, kvm)
1931                 if (v->vcpu_id == id) {
1932                         r = -EEXIST;
1933                         goto unlock_vcpu_destroy;
1934                 }
1935
1936         BUG_ON(kvm->vcpus[atomic_read(&kvm->online_vcpus)]);
1937
1938         /* Now it's all set up, let userspace reach it */
1939         kvm_get_kvm(kvm);
1940         r = create_vcpu_fd(vcpu);
1941         if (r < 0) {
1942                 kvm_put_kvm(kvm);
1943                 goto unlock_vcpu_destroy;
1944         }
1945
1946         kvm->vcpus[atomic_read(&kvm->online_vcpus)] = vcpu;
1947         smp_wmb();
1948         atomic_inc(&kvm->online_vcpus);
1949
1950         mutex_unlock(&kvm->lock);
1951         kvm_arch_vcpu_postcreate(vcpu);
1952         return r;
1953
1954 unlock_vcpu_destroy:
1955         mutex_unlock(&kvm->lock);
1956 vcpu_destroy:
1957         kvm_arch_vcpu_destroy(vcpu);
1958         return r;
1959 }
1960
1961 static int kvm_vcpu_ioctl_set_sigmask(struct kvm_vcpu *vcpu, sigset_t *sigset)
1962 {
1963         if (sigset) {
1964                 sigdelsetmask(sigset, sigmask(SIGKILL)|sigmask(SIGSTOP));
1965                 vcpu->sigset_active = 1;
1966                 vcpu->sigset = *sigset;
1967         } else
1968                 vcpu->sigset_active = 0;
1969         return 0;
1970 }
1971
1972 static long kvm_vcpu_ioctl(struct file *filp,
1973                            unsigned int ioctl, unsigned long arg)
1974 {
1975         struct kvm_vcpu *vcpu = filp->private_data;
1976         void __user *argp = (void __user *)arg;
1977         int r;
1978         struct kvm_fpu *fpu = NULL;
1979         struct kvm_sregs *kvm_sregs = NULL;
1980
1981         if (vcpu->kvm->mm != current->mm)
1982                 return -EIO;
1983
1984 #if defined(CONFIG_S390) || defined(CONFIG_PPC) || defined(CONFIG_MIPS)
1985         /*
1986          * Special cases: vcpu ioctls that are asynchronous to vcpu execution,
1987          * so vcpu_load() would break it.
1988          */
1989         if (ioctl == KVM_S390_INTERRUPT || ioctl == KVM_INTERRUPT)
1990                 return kvm_arch_vcpu_ioctl(filp, ioctl, arg);
1991 #endif
1992
1993
1994         r = vcpu_load(vcpu);
1995         if (r)
1996                 return r;
1997         switch (ioctl) {
1998         case KVM_RUN:
1999                 r = -EINVAL;
2000                 if (arg)
2001                         goto out;
2002                 r = kvm_arch_vcpu_ioctl_run(vcpu, vcpu->run);
2003                 trace_kvm_userspace_exit(vcpu->run->exit_reason, r);
2004                 break;
2005         case KVM_GET_REGS: {
2006                 struct kvm_regs *kvm_regs;
2007
2008                 r = -ENOMEM;
2009                 kvm_regs = kzalloc(sizeof(struct kvm_regs), GFP_KERNEL);
2010                 if (!kvm_regs)
2011                         goto out;
2012                 r = kvm_arch_vcpu_ioctl_get_regs(vcpu, kvm_regs);
2013                 if (r)
2014                         goto out_free1;
2015                 r = -EFAULT;
2016                 if (copy_to_user(argp, kvm_regs, sizeof(struct kvm_regs)))
2017                         goto out_free1;
2018                 r = 0;
2019 out_free1:
2020                 kfree(kvm_regs);
2021                 break;
2022         }
2023         case KVM_SET_REGS: {
2024                 struct kvm_regs *kvm_regs;
2025
2026                 r = -ENOMEM;
2027                 kvm_regs = memdup_user(argp, sizeof(*kvm_regs));
2028                 if (IS_ERR(kvm_regs)) {
2029                         r = PTR_ERR(kvm_regs);
2030                         goto out;
2031                 }
2032                 r = kvm_arch_vcpu_ioctl_set_regs(vcpu, kvm_regs);
2033                 kfree(kvm_regs);
2034                 break;
2035         }
2036         case KVM_GET_SREGS: {
2037                 kvm_sregs = kzalloc(sizeof(struct kvm_sregs), GFP_KERNEL);
2038                 r = -ENOMEM;
2039                 if (!kvm_sregs)
2040                         goto out;
2041                 r = kvm_arch_vcpu_ioctl_get_sregs(vcpu, kvm_sregs);
2042                 if (r)
2043                         goto out;
2044                 r = -EFAULT;
2045                 if (copy_to_user(argp, kvm_sregs, sizeof(struct kvm_sregs)))
2046                         goto out;
2047                 r = 0;
2048                 break;
2049         }
2050         case KVM_SET_SREGS: {
2051                 kvm_sregs = memdup_user(argp, sizeof(*kvm_sregs));
2052                 if (IS_ERR(kvm_sregs)) {
2053                         r = PTR_ERR(kvm_sregs);
2054                         kvm_sregs = NULL;
2055                         goto out;
2056                 }
2057                 r = kvm_arch_vcpu_ioctl_set_sregs(vcpu, kvm_sregs);
2058                 break;
2059         }
2060         case KVM_GET_MP_STATE: {
2061                 struct kvm_mp_state mp_state;
2062
2063                 r = kvm_arch_vcpu_ioctl_get_mpstate(vcpu, &mp_state);
2064                 if (r)
2065                         goto out;
2066                 r = -EFAULT;
2067                 if (copy_to_user(argp, &mp_state, sizeof mp_state))
2068                         goto out;
2069                 r = 0;
2070                 break;
2071         }
2072         case KVM_SET_MP_STATE: {
2073                 struct kvm_mp_state mp_state;
2074
2075                 r = -EFAULT;
2076                 if (copy_from_user(&mp_state, argp, sizeof mp_state))
2077                         goto out;
2078                 r = kvm_arch_vcpu_ioctl_set_mpstate(vcpu, &mp_state);
2079                 break;
2080         }
2081         case KVM_TRANSLATE: {
2082                 struct kvm_translation tr;
2083
2084                 r = -EFAULT;
2085                 if (copy_from_user(&tr, argp, sizeof tr))
2086                         goto out;
2087                 r = kvm_arch_vcpu_ioctl_translate(vcpu, &tr);
2088                 if (r)
2089                         goto out;
2090                 r = -EFAULT;
2091                 if (copy_to_user(argp, &tr, sizeof tr))
2092                         goto out;
2093                 r = 0;
2094                 break;
2095         }
2096         case KVM_SET_GUEST_DEBUG: {
2097                 struct kvm_guest_debug dbg;
2098
2099                 r = -EFAULT;
2100                 if (copy_from_user(&dbg, argp, sizeof dbg))
2101                         goto out;
2102                 r = kvm_arch_vcpu_ioctl_set_guest_debug(vcpu, &dbg);
2103                 break;
2104         }
2105         case KVM_SET_SIGNAL_MASK: {
2106                 struct kvm_signal_mask __user *sigmask_arg = argp;
2107                 struct kvm_signal_mask kvm_sigmask;
2108                 sigset_t sigset, *p;
2109
2110                 p = NULL;
2111                 if (argp) {
2112                         r = -EFAULT;
2113                         if (copy_from_user(&kvm_sigmask, argp,
2114                                            sizeof kvm_sigmask))
2115                                 goto out;
2116                         r = -EINVAL;
2117                         if (kvm_sigmask.len != sizeof sigset)
2118                                 goto out;
2119                         r = -EFAULT;
2120                         if (copy_from_user(&sigset, sigmask_arg->sigset,
2121                                            sizeof sigset))
2122                                 goto out;
2123                         p = &sigset;
2124                 }
2125                 r = kvm_vcpu_ioctl_set_sigmask(vcpu, p);
2126                 break;
2127         }
2128         case KVM_GET_FPU: {
2129                 fpu = kzalloc(sizeof(struct kvm_fpu), GFP_KERNEL);
2130                 r = -ENOMEM;
2131                 if (!fpu)
2132                         goto out;
2133                 r = kvm_arch_vcpu_ioctl_get_fpu(vcpu, fpu);
2134                 if (r)
2135                         goto out;
2136                 r = -EFAULT;
2137                 if (copy_to_user(argp, fpu, sizeof(struct kvm_fpu)))
2138                         goto out;
2139                 r = 0;
2140                 break;
2141         }
2142         case KVM_SET_FPU: {
2143                 fpu = memdup_user(argp, sizeof(*fpu));
2144                 if (IS_ERR(fpu)) {
2145                         r = PTR_ERR(fpu);
2146                         fpu = NULL;
2147                         goto out;
2148                 }
2149                 r = kvm_arch_vcpu_ioctl_set_fpu(vcpu, fpu);
2150                 break;
2151         }
2152         default:
2153                 r = kvm_arch_vcpu_ioctl(filp, ioctl, arg);
2154         }
2155 out:
2156         vcpu_put(vcpu);
2157         kfree(fpu);
2158         kfree(kvm_sregs);
2159         return r;
2160 }
2161
2162 #ifdef CONFIG_COMPAT
2163 static long kvm_vcpu_compat_ioctl(struct file *filp,
2164                                   unsigned int ioctl, unsigned long arg)
2165 {
2166         struct kvm_vcpu *vcpu = filp->private_data;
2167         void __user *argp = compat_ptr(arg);
2168         int r;
2169
2170         if (vcpu->kvm->mm != current->mm)
2171                 return -EIO;
2172
2173         switch (ioctl) {
2174         case KVM_SET_SIGNAL_MASK: {
2175                 struct kvm_signal_mask __user *sigmask_arg = argp;
2176                 struct kvm_signal_mask kvm_sigmask;
2177                 compat_sigset_t csigset;
2178                 sigset_t sigset;
2179
2180                 if (argp) {
2181                         r = -EFAULT;
2182                         if (copy_from_user(&kvm_sigmask, argp,
2183                                            sizeof kvm_sigmask))
2184                                 goto out;
2185                         r = -EINVAL;
2186                         if (kvm_sigmask.len != sizeof csigset)
2187                                 goto out;
2188                         r = -EFAULT;
2189                         if (copy_from_user(&csigset, sigmask_arg->sigset,
2190                                            sizeof csigset))
2191                                 goto out;
2192                         sigset_from_compat(&sigset, &csigset);
2193                         r = kvm_vcpu_ioctl_set_sigmask(vcpu, &sigset);
2194                 } else
2195                         r = kvm_vcpu_ioctl_set_sigmask(vcpu, NULL);
2196                 break;
2197         }
2198         default:
2199                 r = kvm_vcpu_ioctl(filp, ioctl, arg);
2200         }
2201
2202 out:
2203         return r;
2204 }
2205 #endif
2206
2207 static int kvm_device_ioctl_attr(struct kvm_device *dev,
2208                                  int (*accessor)(struct kvm_device *dev,
2209                                                  struct kvm_device_attr *attr),
2210                                  unsigned long arg)
2211 {
2212         struct kvm_device_attr attr;
2213
2214         if (!accessor)
2215                 return -EPERM;
2216
2217         if (copy_from_user(&attr, (void __user *)arg, sizeof(attr)))
2218                 return -EFAULT;
2219
2220         return accessor(dev, &attr);
2221 }
2222
2223 static long kvm_device_ioctl(struct file *filp, unsigned int ioctl,
2224                              unsigned long arg)
2225 {
2226         struct kvm_device *dev = filp->private_data;
2227
2228         switch (ioctl) {
2229         case KVM_SET_DEVICE_ATTR:
2230                 return kvm_device_ioctl_attr(dev, dev->ops->set_attr, arg);
2231         case KVM_GET_DEVICE_ATTR:
2232                 return kvm_device_ioctl_attr(dev, dev->ops->get_attr, arg);
2233         case KVM_HAS_DEVICE_ATTR:
2234                 return kvm_device_ioctl_attr(dev, dev->ops->has_attr, arg);
2235         default:
2236                 if (dev->ops->ioctl)
2237                         return dev->ops->ioctl(dev, ioctl, arg);
2238
2239                 return -ENOTTY;
2240         }
2241 }
2242
2243 static int kvm_device_release(struct inode *inode, struct file *filp)
2244 {
2245         struct kvm_device *dev = filp->private_data;
2246         struct kvm *kvm = dev->kvm;
2247
2248         kvm_put_kvm(kvm);
2249         return 0;
2250 }
2251
2252 static const struct file_operations kvm_device_fops = {
2253         .unlocked_ioctl = kvm_device_ioctl,
2254 #ifdef CONFIG_COMPAT
2255         .compat_ioctl = kvm_device_ioctl,
2256 #endif
2257         .release = kvm_device_release,
2258 };
2259
2260 struct kvm_device *kvm_device_from_filp(struct file *filp)
2261 {
2262         if (filp->f_op != &kvm_device_fops)
2263                 return NULL;
2264
2265         return filp->private_data;
2266 }
2267
2268 static int kvm_ioctl_create_device(struct kvm *kvm,
2269                                    struct kvm_create_device *cd)
2270 {
2271         struct kvm_device_ops *ops = NULL;
2272         struct kvm_device *dev;
2273         bool test = cd->flags & KVM_CREATE_DEVICE_TEST;
2274         int ret;
2275
2276         switch (cd->type) {
2277 #ifdef CONFIG_KVM_MPIC
2278         case KVM_DEV_TYPE_FSL_MPIC_20:
2279         case KVM_DEV_TYPE_FSL_MPIC_42:
2280                 ops = &kvm_mpic_ops;
2281                 break;
2282 #endif
2283 #ifdef CONFIG_KVM_XICS
2284         case KVM_DEV_TYPE_XICS:
2285                 ops = &kvm_xics_ops;
2286                 break;
2287 #endif
2288         default:
2289                 return -ENODEV;
2290         }
2291
2292         if (test)
2293                 return 0;
2294
2295         dev = kzalloc(sizeof(*dev), GFP_KERNEL);
2296         if (!dev)
2297                 return -ENOMEM;
2298
2299         dev->ops = ops;
2300         dev->kvm = kvm;
2301
2302         ret = ops->create(dev, cd->type);
2303         if (ret < 0) {
2304                 kfree(dev);
2305                 return ret;
2306         }
2307
2308         ret = anon_inode_getfd(ops->name, &kvm_device_fops, dev, O_RDWR);
2309         if (ret < 0) {
2310                 ops->destroy(dev);
2311                 return ret;
2312         }
2313
2314         list_add(&dev->vm_node, &kvm->devices);
2315         kvm_get_kvm(kvm);
2316         cd->fd = ret;
2317         return 0;
2318 }
2319
2320 static long kvm_vm_ioctl(struct file *filp,
2321                            unsigned int ioctl, unsigned long arg)
2322 {
2323         struct kvm *kvm = filp->private_data;
2324         void __user *argp = (void __user *)arg;
2325         int r;
2326
2327         if (kvm->mm != current->mm)
2328                 return -EIO;
2329         switch (ioctl) {
2330         case KVM_CREATE_VCPU:
2331                 r = kvm_vm_ioctl_create_vcpu(kvm, arg);
2332                 break;
2333         case KVM_SET_USER_MEMORY_REGION: {
2334                 struct kvm_userspace_memory_region kvm_userspace_mem;
2335
2336                 r = -EFAULT;
2337                 if (copy_from_user(&kvm_userspace_mem, argp,
2338                                                 sizeof kvm_userspace_mem))
2339                         goto out;
2340
2341                 r = kvm_vm_ioctl_set_memory_region(kvm, &kvm_userspace_mem);
2342                 break;
2343         }
2344         case KVM_GET_DIRTY_LOG: {
2345                 struct kvm_dirty_log log;
2346
2347                 r = -EFAULT;
2348                 if (copy_from_user(&log, argp, sizeof log))
2349                         goto out;
2350                 r = kvm_vm_ioctl_get_dirty_log(kvm, &log);
2351                 break;
2352         }
2353 #ifdef KVM_COALESCED_MMIO_PAGE_OFFSET
2354         case KVM_REGISTER_COALESCED_MMIO: {
2355                 struct kvm_coalesced_mmio_zone zone;
2356                 r = -EFAULT;
2357                 if (copy_from_user(&zone, argp, sizeof zone))
2358                         goto out;
2359                 r = kvm_vm_ioctl_register_coalesced_mmio(kvm, &zone);
2360                 break;
2361         }
2362         case KVM_UNREGISTER_COALESCED_MMIO: {
2363                 struct kvm_coalesced_mmio_zone zone;
2364                 r = -EFAULT;
2365                 if (copy_from_user(&zone, argp, sizeof zone))
2366                         goto out;
2367                 r = kvm_vm_ioctl_unregister_coalesced_mmio(kvm, &zone);
2368                 break;
2369         }
2370 #endif
2371         case KVM_IRQFD: {
2372                 struct kvm_irqfd data;
2373
2374                 r = -EFAULT;
2375                 if (copy_from_user(&data, argp, sizeof data))
2376                         goto out;
2377                 r = kvm_irqfd(kvm, &data);
2378                 break;
2379         }
2380         case KVM_IOEVENTFD: {
2381                 struct kvm_ioeventfd data;
2382
2383                 r = -EFAULT;
2384                 if (copy_from_user(&data, argp, sizeof data))
2385                         goto out;
2386                 r = kvm_ioeventfd(kvm, &data);
2387                 break;
2388         }
2389 #ifdef CONFIG_KVM_APIC_ARCHITECTURE
2390         case KVM_SET_BOOT_CPU_ID:
2391                 r = 0;
2392                 mutex_lock(&kvm->lock);
2393                 if (atomic_read(&kvm->online_vcpus) != 0)
2394                         r = -EBUSY;
2395                 else
2396                         kvm->bsp_vcpu_id = arg;
2397                 mutex_unlock(&kvm->lock);
2398                 break;
2399 #endif
2400 #ifdef CONFIG_HAVE_KVM_MSI
2401         case KVM_SIGNAL_MSI: {
2402                 struct kvm_msi msi;
2403
2404                 r = -EFAULT;
2405                 if (copy_from_user(&msi, argp, sizeof msi))
2406                         goto out;
2407                 r = kvm_send_userspace_msi(kvm, &msi);
2408                 break;
2409         }
2410 #endif
2411 #ifdef __KVM_HAVE_IRQ_LINE
2412         case KVM_IRQ_LINE_STATUS:
2413         case KVM_IRQ_LINE: {
2414                 struct kvm_irq_level irq_event;
2415
2416                 r = -EFAULT;
2417                 if (copy_from_user(&irq_event, argp, sizeof irq_event))
2418                         goto out;
2419
2420                 r = kvm_vm_ioctl_irq_line(kvm, &irq_event,
2421                                         ioctl == KVM_IRQ_LINE_STATUS);
2422                 if (r)
2423                         goto out;
2424
2425                 r = -EFAULT;
2426                 if (ioctl == KVM_IRQ_LINE_STATUS) {
2427                         if (copy_to_user(argp, &irq_event, sizeof irq_event))
2428                                 goto out;
2429                 }
2430
2431                 r = 0;
2432                 break;
2433         }
2434 #endif
2435 #ifdef CONFIG_HAVE_KVM_IRQ_ROUTING
2436         case KVM_SET_GSI_ROUTING: {
2437                 struct kvm_irq_routing routing;
2438                 struct kvm_irq_routing __user *urouting;
2439                 struct kvm_irq_routing_entry *entries;
2440
2441                 r = -EFAULT;
2442                 if (copy_from_user(&routing, argp, sizeof(routing)))
2443                         goto out;
2444                 r = -EINVAL;
2445                 if (routing.nr >= KVM_MAX_IRQ_ROUTES)
2446                         goto out;
2447                 if (routing.flags)
2448                         goto out;
2449                 r = -ENOMEM;
2450                 entries = vmalloc(routing.nr * sizeof(*entries));
2451                 if (!entries)
2452                         goto out;
2453                 r = -EFAULT;
2454                 urouting = argp;
2455                 if (copy_from_user(entries, urouting->entries,
2456                                    routing.nr * sizeof(*entries)))
2457                         goto out_free_irq_routing;
2458                 r = kvm_set_irq_routing(kvm, entries, routing.nr,
2459                                         routing.flags);
2460         out_free_irq_routing:
2461                 vfree(entries);
2462                 break;
2463         }
2464 #endif /* CONFIG_HAVE_KVM_IRQ_ROUTING */
2465         case KVM_CREATE_DEVICE: {
2466                 struct kvm_create_device cd;
2467
2468                 r = -EFAULT;
2469                 if (copy_from_user(&cd, argp, sizeof(cd)))
2470                         goto out;
2471
2472                 r = kvm_ioctl_create_device(kvm, &cd);
2473                 if (r)
2474                         goto out;
2475
2476                 r = -EFAULT;
2477                 if (copy_to_user(argp, &cd, sizeof(cd)))
2478                         goto out;
2479
2480                 r = 0;
2481                 break;
2482         }
2483         default:
2484                 r = kvm_arch_vm_ioctl(filp, ioctl, arg);
2485                 if (r == -ENOTTY)
2486                         r = kvm_vm_ioctl_assigned_device(kvm, ioctl, arg);
2487         }
2488 out:
2489         return r;
2490 }
2491
2492 #ifdef CONFIG_COMPAT
2493 struct compat_kvm_dirty_log {
2494         __u32 slot;
2495         __u32 padding1;
2496         union {
2497                 compat_uptr_t dirty_bitmap; /* one bit per page */
2498                 __u64 padding2;
2499         };
2500 };
2501
2502 static long kvm_vm_compat_ioctl(struct file *filp,
2503                            unsigned int ioctl, unsigned long arg)
2504 {
2505         struct kvm *kvm = filp->private_data;
2506         int r;
2507
2508         if (kvm->mm != current->mm)
2509                 return -EIO;
2510         switch (ioctl) {
2511         case KVM_GET_DIRTY_LOG: {
2512                 struct compat_kvm_dirty_log compat_log;
2513                 struct kvm_dirty_log log;
2514
2515                 r = -EFAULT;
2516                 if (copy_from_user(&compat_log, (void __user *)arg,
2517                                    sizeof(compat_log)))
2518                         goto out;
2519                 log.slot         = compat_log.slot;
2520                 log.padding1     = compat_log.padding1;
2521                 log.padding2     = compat_log.padding2;
2522                 log.dirty_bitmap = compat_ptr(compat_log.dirty_bitmap);
2523
2524                 r = kvm_vm_ioctl_get_dirty_log(kvm, &log);
2525                 break;
2526         }
2527         default:
2528                 r = kvm_vm_ioctl(filp, ioctl, arg);
2529         }
2530
2531 out:
2532         return r;
2533 }
2534 #endif
2535
2536 static int kvm_vm_fault(struct vm_area_struct *vma, struct vm_fault *vmf)
2537 {
2538         struct page *page[1];
2539         unsigned long addr;
2540         int npages;
2541         gfn_t gfn = vmf->pgoff;
2542         struct kvm *kvm = vma->vm_file->private_data;
2543
2544         addr = gfn_to_hva(kvm, gfn);
2545         if (kvm_is_error_hva(addr))
2546                 return VM_FAULT_SIGBUS;
2547
2548         npages = get_user_pages(current, current->mm, addr, 1, 1, 0, page,
2549                                 NULL);
2550         if (unlikely(npages != 1))
2551                 return VM_FAULT_SIGBUS;
2552
2553         vmf->page = page[0];
2554         return 0;
2555 }
2556
2557 static const struct vm_operations_struct kvm_vm_vm_ops = {
2558         .fault = kvm_vm_fault,
2559 };
2560
2561 static int kvm_vm_mmap(struct file *file, struct vm_area_struct *vma)
2562 {
2563         vma->vm_ops = &kvm_vm_vm_ops;
2564         return 0;
2565 }
2566
2567 static struct file_operations kvm_vm_fops = {
2568         .release        = kvm_vm_release,
2569         .unlocked_ioctl = kvm_vm_ioctl,
2570 #ifdef CONFIG_COMPAT
2571         .compat_ioctl   = kvm_vm_compat_ioctl,
2572 #endif
2573         .mmap           = kvm_vm_mmap,
2574         .llseek         = noop_llseek,
2575 };
2576
2577 static int kvm_dev_ioctl_create_vm(unsigned long type)
2578 {
2579         int r;
2580         struct kvm *kvm;
2581
2582         kvm = kvm_create_vm(type);
2583         if (IS_ERR(kvm))
2584                 return PTR_ERR(kvm);
2585 #ifdef KVM_COALESCED_MMIO_PAGE_OFFSET
2586         r = kvm_coalesced_mmio_init(kvm);
2587         if (r < 0) {
2588                 kvm_put_kvm(kvm);
2589                 return r;
2590         }
2591 #endif
2592         r = anon_inode_getfd("kvm-vm", &kvm_vm_fops, kvm, O_RDWR);
2593         if (r < 0)
2594                 kvm_put_kvm(kvm);
2595
2596         return r;
2597 }
2598
2599 static long kvm_dev_ioctl_check_extension_generic(long arg)
2600 {
2601         switch (arg) {
2602         case KVM_CAP_USER_MEMORY:
2603         case KVM_CAP_DESTROY_MEMORY_REGION_WORKS:
2604         case KVM_CAP_JOIN_MEMORY_REGIONS_WORKS:
2605 #ifdef CONFIG_KVM_APIC_ARCHITECTURE
2606         case KVM_CAP_SET_BOOT_CPU_ID:
2607 #endif
2608         case KVM_CAP_INTERNAL_ERROR_DATA:
2609 #ifdef CONFIG_HAVE_KVM_MSI
2610         case KVM_CAP_SIGNAL_MSI:
2611 #endif
2612 #ifdef CONFIG_HAVE_KVM_IRQ_ROUTING
2613         case KVM_CAP_IRQFD_RESAMPLE:
2614 #endif
2615                 return 1;
2616 #ifdef CONFIG_HAVE_KVM_IRQ_ROUTING
2617         case KVM_CAP_IRQ_ROUTING:
2618                 return KVM_MAX_IRQ_ROUTES;
2619 #endif
2620         default:
2621                 break;
2622         }
2623         return kvm_dev_ioctl_check_extension(arg);
2624 }
2625
2626 static long kvm_dev_ioctl(struct file *filp,
2627                           unsigned int ioctl, unsigned long arg)
2628 {
2629         long r = -EINVAL;
2630
2631         switch (ioctl) {
2632         case KVM_GET_API_VERSION:
2633                 r = -EINVAL;
2634                 if (arg)
2635                         goto out;
2636                 r = KVM_API_VERSION;
2637                 break;
2638         case KVM_CREATE_VM:
2639                 r = kvm_dev_ioctl_create_vm(arg);
2640                 break;
2641         case KVM_CHECK_EXTENSION:
2642                 r = kvm_dev_ioctl_check_extension_generic(arg);
2643                 break;
2644         case KVM_GET_VCPU_MMAP_SIZE:
2645                 r = -EINVAL;
2646                 if (arg)
2647                         goto out;
2648                 r = PAGE_SIZE;     /* struct kvm_run */
2649 #ifdef CONFIG_X86
2650                 r += PAGE_SIZE;    /* pio data page */
2651 #endif
2652 #ifdef KVM_COALESCED_MMIO_PAGE_OFFSET
2653                 r += PAGE_SIZE;    /* coalesced mmio ring page */
2654 #endif
2655                 break;
2656         case KVM_TRACE_ENABLE:
2657         case KVM_TRACE_PAUSE:
2658         case KVM_TRACE_DISABLE:
2659                 r = -EOPNOTSUPP;
2660                 break;
2661         default:
2662                 return kvm_arch_dev_ioctl(filp, ioctl, arg);
2663         }
2664 out:
2665         return r;
2666 }
2667
2668 static struct file_operations kvm_chardev_ops = {
2669         .unlocked_ioctl = kvm_dev_ioctl,
2670         .compat_ioctl   = kvm_dev_ioctl,
2671         .llseek         = noop_llseek,
2672 };
2673
2674 static struct miscdevice kvm_dev = {
2675         KVM_MINOR,
2676         "kvm",
2677         &kvm_chardev_ops,
2678 };
2679
2680 static void hardware_enable_nolock(void *junk)
2681 {
2682         int cpu = raw_smp_processor_id();
2683         int r;
2684
2685         if (cpumask_test_cpu(cpu, cpus_hardware_enabled))
2686                 return;
2687
2688         cpumask_set_cpu(cpu, cpus_hardware_enabled);
2689
2690         r = kvm_arch_hardware_enable(NULL);
2691
2692         if (r) {
2693                 cpumask_clear_cpu(cpu, cpus_hardware_enabled);
2694                 atomic_inc(&hardware_enable_failed);
2695                 printk(KERN_INFO "kvm: enabling virtualization on "
2696                                  "CPU%d failed\n", cpu);
2697         }
2698 }
2699
2700 static void hardware_enable(void *junk)
2701 {
2702         raw_spin_lock(&kvm_lock);
2703         hardware_enable_nolock(junk);
2704         raw_spin_unlock(&kvm_lock);
2705 }
2706
2707 static void hardware_disable_nolock(void *junk)
2708 {
2709         int cpu = raw_smp_processor_id();
2710
2711         if (!cpumask_test_cpu(cpu, cpus_hardware_enabled))
2712                 return;
2713         cpumask_clear_cpu(cpu, cpus_hardware_enabled);
2714         kvm_arch_hardware_disable(NULL);
2715 }
2716
2717 static void hardware_disable(void *junk)
2718 {
2719         raw_spin_lock(&kvm_lock);
2720         hardware_disable_nolock(junk);
2721         raw_spin_unlock(&kvm_lock);
2722 }
2723
2724 static void hardware_disable_all_nolock(void)
2725 {
2726         BUG_ON(!kvm_usage_count);
2727
2728         kvm_usage_count--;
2729         if (!kvm_usage_count)
2730                 on_each_cpu(hardware_disable_nolock, NULL, 1);
2731 }
2732
2733 static void hardware_disable_all(void)
2734 {
2735         raw_spin_lock(&kvm_lock);
2736         hardware_disable_all_nolock();
2737         raw_spin_unlock(&kvm_lock);
2738 }
2739
2740 static int hardware_enable_all(void)
2741 {
2742         int r = 0;
2743
2744         raw_spin_lock(&kvm_lock);
2745
2746         kvm_usage_count++;
2747         if (kvm_usage_count == 1) {
2748                 atomic_set(&hardware_enable_failed, 0);
2749                 on_each_cpu(hardware_enable_nolock, NULL, 1);
2750
2751                 if (atomic_read(&hardware_enable_failed)) {
2752                         hardware_disable_all_nolock();
2753                         r = -EBUSY;
2754                 }
2755         }
2756
2757         raw_spin_unlock(&kvm_lock);
2758
2759         return r;
2760 }
2761
2762 static int kvm_cpu_hotplug(struct notifier_block *notifier, unsigned long val,
2763                            void *v)
2764 {
2765         int cpu = (long)v;
2766
2767         if (!kvm_usage_count)
2768                 return NOTIFY_OK;
2769
2770         val &= ~CPU_TASKS_FROZEN;
2771         switch (val) {
2772         case CPU_DYING:
2773                 printk(KERN_INFO "kvm: disabling virtualization on CPU%d\n",
2774                        cpu);
2775                 hardware_disable(NULL);
2776                 break;
2777         case CPU_STARTING:
2778                 printk(KERN_INFO "kvm: enabling virtualization on CPU%d\n",
2779                        cpu);
2780                 hardware_enable(NULL);
2781                 break;
2782         }
2783         return NOTIFY_OK;
2784 }
2785
2786 static int kvm_reboot(struct notifier_block *notifier, unsigned long val,
2787                       void *v)
2788 {
2789         /*
2790          * Some (well, at least mine) BIOSes hang on reboot if
2791          * in vmx root mode.
2792          *
2793          * And Intel TXT required VMX off for all cpu when system shutdown.
2794          */
2795         printk(KERN_INFO "kvm: exiting hardware virtualization\n");
2796         kvm_rebooting = true;
2797         on_each_cpu(hardware_disable_nolock, NULL, 1);
2798         return NOTIFY_OK;
2799 }
2800
2801 static struct notifier_block kvm_reboot_notifier = {
2802         .notifier_call = kvm_reboot,
2803         .priority = 0,
2804 };
2805
2806 static void kvm_io_bus_destroy(struct kvm_io_bus *bus)
2807 {
2808         int i;
2809
2810         for (i = 0; i < bus->dev_count; i++) {
2811                 struct kvm_io_device *pos = bus->range[i].dev;
2812
2813                 kvm_iodevice_destructor(pos);
2814         }
2815         kfree(bus);
2816 }
2817
2818 static inline int __kvm_io_bus_sort_cmp(const struct kvm_io_range *r1,
2819                                         const struct kvm_io_range *r2)
2820 {
2821         if (r1->addr < r2->addr)
2822                 return -1;
2823         if (r1->addr + r1->len > r2->addr + r2->len)
2824                 return 1;
2825         return 0;
2826 }
2827
2828 static int kvm_io_bus_sort_cmp(const void *p1, const void *p2)
2829 {
2830         return __kvm_io_bus_sort_cmp(p1, p2);
2831 }
2832
2833 static int kvm_io_bus_insert_dev(struct kvm_io_bus *bus, struct kvm_io_device *dev,
2834                           gpa_t addr, int len)
2835 {
2836         bus->range[bus->dev_count++] = (struct kvm_io_range) {
2837                 .addr = addr,
2838                 .len = len,
2839                 .dev = dev,
2840         };
2841
2842         sort(bus->range, bus->dev_count, sizeof(struct kvm_io_range),
2843                 kvm_io_bus_sort_cmp, NULL);
2844
2845         return 0;
2846 }
2847
2848 static int kvm_io_bus_get_first_dev(struct kvm_io_bus *bus,
2849                              gpa_t addr, int len)
2850 {
2851         struct kvm_io_range *range, key;
2852         int off;
2853
2854         key = (struct kvm_io_range) {
2855                 .addr = addr,
2856                 .len = len,
2857         };
2858
2859         range = bsearch(&key, bus->range, bus->dev_count,
2860                         sizeof(struct kvm_io_range), kvm_io_bus_sort_cmp);
2861         if (range == NULL)
2862                 return -ENOENT;
2863
2864         off = range - bus->range;
2865
2866         while (off > 0 && __kvm_io_bus_sort_cmp(&key, &bus->range[off-1]) == 0)
2867                 off--;
2868
2869         return off;
2870 }
2871
2872 static int __kvm_io_bus_write(struct kvm_io_bus *bus,
2873                               struct kvm_io_range *range, const void *val)
2874 {
2875         int idx;
2876
2877         idx = kvm_io_bus_get_first_dev(bus, range->addr, range->len);
2878         if (idx < 0)
2879                 return -EOPNOTSUPP;
2880
2881         while (idx < bus->dev_count &&
2882                 __kvm_io_bus_sort_cmp(range, &bus->range[idx]) == 0) {
2883                 if (!kvm_iodevice_write(bus->range[idx].dev, range->addr,
2884                                         range->len, val))
2885                         return idx;
2886                 idx++;
2887         }
2888
2889         return -EOPNOTSUPP;
2890 }
2891
2892 /* kvm_io_bus_write - called under kvm->slots_lock */
2893 int kvm_io_bus_write(struct kvm *kvm, enum kvm_bus bus_idx, gpa_t addr,
2894                      int len, const void *val)
2895 {
2896         struct kvm_io_bus *bus;
2897         struct kvm_io_range range;
2898         int r;
2899
2900         range = (struct kvm_io_range) {
2901                 .addr = addr,
2902                 .len = len,
2903         };
2904
2905         bus = srcu_dereference(kvm->buses[bus_idx], &kvm->srcu);
2906         r = __kvm_io_bus_write(bus, &range, val);
2907         return r < 0 ? r : 0;
2908 }
2909
2910 /* kvm_io_bus_write_cookie - called under kvm->slots_lock */
2911 int kvm_io_bus_write_cookie(struct kvm *kvm, enum kvm_bus bus_idx, gpa_t addr,
2912                             int len, const void *val, long cookie)
2913 {
2914         struct kvm_io_bus *bus;
2915         struct kvm_io_range range;
2916
2917         range = (struct kvm_io_range) {
2918                 .addr = addr,
2919                 .len = len,
2920         };
2921
2922         bus = srcu_dereference(kvm->buses[bus_idx], &kvm->srcu);
2923
2924         /* First try the device referenced by cookie. */
2925         if ((cookie >= 0) && (cookie < bus->dev_count) &&
2926             (__kvm_io_bus_sort_cmp(&range, &bus->range[cookie]) == 0))
2927                 if (!kvm_iodevice_write(bus->range[cookie].dev, addr, len,
2928                                         val))
2929                         return cookie;
2930
2931         /*
2932          * cookie contained garbage; fall back to search and return the
2933          * correct cookie value.
2934          */
2935         return __kvm_io_bus_write(bus, &range, val);
2936 }
2937
2938 static int __kvm_io_bus_read(struct kvm_io_bus *bus, struct kvm_io_range *range,
2939                              void *val)
2940 {
2941         int idx;
2942
2943         idx = kvm_io_bus_get_first_dev(bus, range->addr, range->len);
2944         if (idx < 0)
2945                 return -EOPNOTSUPP;
2946
2947         while (idx < bus->dev_count &&
2948                 __kvm_io_bus_sort_cmp(range, &bus->range[idx]) == 0) {
2949                 if (!kvm_iodevice_read(bus->range[idx].dev, range->addr,
2950                                        range->len, val))
2951                         return idx;
2952                 idx++;
2953         }
2954
2955         return -EOPNOTSUPP;
2956 }
2957
2958 /* kvm_io_bus_read - called under kvm->slots_lock */
2959 int kvm_io_bus_read(struct kvm *kvm, enum kvm_bus bus_idx, gpa_t addr,
2960                     int len, void *val)
2961 {
2962         struct kvm_io_bus *bus;
2963         struct kvm_io_range range;
2964         int r;
2965
2966         range = (struct kvm_io_range) {
2967                 .addr = addr,
2968                 .len = len,
2969         };
2970
2971         bus = srcu_dereference(kvm->buses[bus_idx], &kvm->srcu);
2972         r = __kvm_io_bus_read(bus, &range, val);
2973         return r < 0 ? r : 0;
2974 }
2975
2976 /* kvm_io_bus_read_cookie - called under kvm->slots_lock */
2977 int kvm_io_bus_read_cookie(struct kvm *kvm, enum kvm_bus bus_idx, gpa_t addr,
2978                            int len, void *val, long cookie)
2979 {
2980         struct kvm_io_bus *bus;
2981         struct kvm_io_range range;
2982
2983         range = (struct kvm_io_range) {
2984                 .addr = addr,
2985                 .len = len,
2986         };
2987
2988         bus = srcu_dereference(kvm->buses[bus_idx], &kvm->srcu);
2989
2990         /* First try the device referenced by cookie. */
2991         if ((cookie >= 0) && (cookie < bus->dev_count) &&
2992             (__kvm_io_bus_sort_cmp(&range, &bus->range[cookie]) == 0))
2993                 if (!kvm_iodevice_read(bus->range[cookie].dev, addr, len,
2994                                        val))
2995                         return cookie;
2996
2997         /*
2998          * cookie contained garbage; fall back to search and return the
2999          * correct cookie value.
3000          */
3001         return __kvm_io_bus_read(bus, &range, val);
3002 }
3003
3004 /* Caller must hold slots_lock. */
3005 int kvm_io_bus_register_dev(struct kvm *kvm, enum kvm_bus bus_idx, gpa_t addr,
3006                             int len, struct kvm_io_device *dev)
3007 {
3008         struct kvm_io_bus *new_bus, *bus;
3009
3010         bus = kvm->buses[bus_idx];
3011         /* exclude ioeventfd which is limited by maximum fd */
3012         if (bus->dev_count - bus->ioeventfd_count > NR_IOBUS_DEVS - 1)
3013                 return -ENOSPC;
3014
3015         new_bus = kzalloc(sizeof(*bus) + ((bus->dev_count + 1) *
3016                           sizeof(struct kvm_io_range)), GFP_KERNEL);
3017         if (!new_bus)
3018                 return -ENOMEM;
3019         memcpy(new_bus, bus, sizeof(*bus) + (bus->dev_count *
3020                sizeof(struct kvm_io_range)));
3021         kvm_io_bus_insert_dev(new_bus, dev, addr, len);
3022         rcu_assign_pointer(kvm->buses[bus_idx], new_bus);
3023         synchronize_srcu_expedited(&kvm->srcu);
3024         kfree(bus);
3025
3026         return 0;
3027 }
3028
3029 /* Caller must hold slots_lock. */
3030 int kvm_io_bus_unregister_dev(struct kvm *kvm, enum kvm_bus bus_idx,
3031                               struct kvm_io_device *dev)
3032 {
3033         int i, r;
3034         struct kvm_io_bus *new_bus, *bus;
3035
3036         bus = kvm->buses[bus_idx];
3037         r = -ENOENT;
3038         for (i = 0; i < bus->dev_count; i++)
3039                 if (bus->range[i].dev == dev) {
3040                         r = 0;
3041                         break;
3042                 }
3043
3044         if (r)
3045                 return r;
3046
3047         new_bus = kzalloc(sizeof(*bus) + ((bus->dev_count - 1) *
3048                           sizeof(struct kvm_io_range)), GFP_KERNEL);
3049         if (!new_bus)
3050                 return -ENOMEM;
3051
3052         memcpy(new_bus, bus, sizeof(*bus) + i * sizeof(struct kvm_io_range));
3053         new_bus->dev_count--;
3054         memcpy(new_bus->range + i, bus->range + i + 1,
3055                (new_bus->dev_count - i) * sizeof(struct kvm_io_range));
3056
3057         rcu_assign_pointer(kvm->buses[bus_idx], new_bus);
3058         synchronize_srcu_expedited(&kvm->srcu);
3059         kfree(bus);
3060         return r;
3061 }
3062
3063 static struct notifier_block kvm_cpu_notifier = {
3064         .notifier_call = kvm_cpu_hotplug,
3065 };
3066
3067 static int vm_stat_get(void *_offset, u64 *val)
3068 {
3069         unsigned offset = (long)_offset;
3070         struct kvm *kvm;
3071
3072         *val = 0;
3073         raw_spin_lock(&kvm_lock);
3074         list_for_each_entry(kvm, &vm_list, vm_list)
3075                 *val += *(u32 *)((void *)kvm + offset);
3076         raw_spin_unlock(&kvm_lock);
3077         return 0;
3078 }
3079
3080 DEFINE_SIMPLE_ATTRIBUTE(vm_stat_fops, vm_stat_get, NULL, "%llu\n");
3081
3082 static int vcpu_stat_get(void *_offset, u64 *val)
3083 {
3084         unsigned offset = (long)_offset;
3085         struct kvm *kvm;
3086         struct kvm_vcpu *vcpu;
3087         int i;
3088
3089         *val = 0;
3090         raw_spin_lock(&kvm_lock);
3091         list_for_each_entry(kvm, &vm_list, vm_list)
3092                 kvm_for_each_vcpu(i, vcpu, kvm)
3093                         *val += *(u32 *)((void *)vcpu + offset);
3094
3095         raw_spin_unlock(&kvm_lock);
3096         return 0;
3097 }
3098
3099 DEFINE_SIMPLE_ATTRIBUTE(vcpu_stat_fops, vcpu_stat_get, NULL, "%llu\n");
3100
3101 static const struct file_operations *stat_fops[] = {
3102         [KVM_STAT_VCPU] = &vcpu_stat_fops,
3103         [KVM_STAT_VM]   = &vm_stat_fops,
3104 };
3105
3106 static int kvm_init_debug(void)
3107 {
3108         int r = -EFAULT;
3109         struct kvm_stats_debugfs_item *p;
3110
3111         kvm_debugfs_dir = debugfs_create_dir("kvm", NULL);
3112         if (kvm_debugfs_dir == NULL)
3113                 goto out;
3114
3115         for (p = debugfs_entries; p->name; ++p) {
3116                 p->dentry = debugfs_create_file(p->name, 0444, kvm_debugfs_dir,
3117                                                 (void *)(long)p->offset,
3118                                                 stat_fops[p->kind]);
3119                 if (p->dentry == NULL)
3120                         goto out_dir;
3121         }
3122
3123         return 0;
3124
3125 out_dir:
3126         debugfs_remove_recursive(kvm_debugfs_dir);
3127 out:
3128         return r;
3129 }
3130
3131 static void kvm_exit_debug(void)
3132 {
3133         struct kvm_stats_debugfs_item *p;
3134
3135         for (p = debugfs_entries; p->name; ++p)
3136                 debugfs_remove(p->dentry);
3137         debugfs_remove(kvm_debugfs_dir);
3138 }
3139
3140 static int kvm_suspend(void)
3141 {
3142         if (kvm_usage_count)
3143                 hardware_disable_nolock(NULL);
3144         return 0;
3145 }
3146
3147 static void kvm_resume(void)
3148 {
3149         if (kvm_usage_count) {
3150                 WARN_ON(raw_spin_is_locked(&kvm_lock));
3151                 hardware_enable_nolock(NULL);
3152         }
3153 }
3154
3155 static struct syscore_ops kvm_syscore_ops = {
3156         .suspend = kvm_suspend,
3157         .resume = kvm_resume,
3158 };
3159
3160 static inline
3161 struct kvm_vcpu *preempt_notifier_to_vcpu(struct preempt_notifier *pn)
3162 {
3163         return container_of(pn, struct kvm_vcpu, preempt_notifier);
3164 }
3165
3166 static void kvm_sched_in(struct preempt_notifier *pn, int cpu)
3167 {
3168         struct kvm_vcpu *vcpu = preempt_notifier_to_vcpu(pn);
3169         if (vcpu->preempted)
3170                 vcpu->preempted = false;
3171
3172         kvm_arch_vcpu_load(vcpu, cpu);
3173 }
3174
3175 static void kvm_sched_out(struct preempt_notifier *pn,
3176                           struct task_struct *next)
3177 {
3178         struct kvm_vcpu *vcpu = preempt_notifier_to_vcpu(pn);
3179
3180         if (current->state == TASK_RUNNING)
3181                 vcpu->preempted = true;
3182         kvm_arch_vcpu_put(vcpu);
3183 }
3184
3185 int kvm_init(void *opaque, unsigned vcpu_size, unsigned vcpu_align,
3186                   struct module *module)
3187 {
3188         int r;
3189         int cpu;
3190
3191         r = kvm_arch_init(opaque);
3192         if (r)
3193                 goto out_fail;
3194
3195         /*
3196          * kvm_arch_init makes sure there's at most one caller
3197          * for architectures that support multiple implementations,
3198          * like intel and amd on x86.
3199          * kvm_arch_init must be called before kvm_irqfd_init to avoid creating
3200          * conflicts in case kvm is already setup for another implementation.
3201          */
3202         r = kvm_irqfd_init();
3203         if (r)
3204                 goto out_irqfd;
3205
3206         if (!zalloc_cpumask_var(&cpus_hardware_enabled, GFP_KERNEL)) {
3207                 r = -ENOMEM;
3208                 goto out_free_0;
3209         }
3210
3211         r = kvm_arch_hardware_setup();
3212         if (r < 0)
3213                 goto out_free_0a;
3214
3215         for_each_online_cpu(cpu) {
3216                 smp_call_function_single(cpu,
3217                                 kvm_arch_check_processor_compat,
3218                                 &r, 1);
3219                 if (r < 0)
3220                         goto out_free_1;
3221         }
3222
3223         r = register_cpu_notifier(&kvm_cpu_notifier);
3224         if (r)
3225                 goto out_free_2;
3226         register_reboot_notifier(&kvm_reboot_notifier);
3227
3228         /* A kmem cache lets us meet the alignment requirements of fx_save. */
3229         if (!vcpu_align)
3230                 vcpu_align = __alignof__(struct kvm_vcpu);
3231         kvm_vcpu_cache = kmem_cache_create("kvm_vcpu", vcpu_size, vcpu_align,
3232                                            0, NULL);
3233         if (!kvm_vcpu_cache) {
3234                 r = -ENOMEM;
3235                 goto out_free_3;
3236         }
3237
3238         r = kvm_async_pf_init();
3239         if (r)
3240                 goto out_free;
3241
3242         kvm_chardev_ops.owner = module;
3243         kvm_vm_fops.owner = module;
3244         kvm_vcpu_fops.owner = module;
3245
3246         r = misc_register(&kvm_dev);
3247         if (r) {
3248                 printk(KERN_ERR "kvm: misc device register failed\n");
3249                 goto out_unreg;
3250         }
3251
3252         register_syscore_ops(&kvm_syscore_ops);
3253
3254         kvm_preempt_ops.sched_in = kvm_sched_in;
3255         kvm_preempt_ops.sched_out = kvm_sched_out;
3256
3257         r = kvm_init_debug();
3258         if (r) {
3259                 printk(KERN_ERR "kvm: create debugfs files failed\n");
3260                 goto out_undebugfs;
3261         }
3262
3263         return 0;
3264
3265 out_undebugfs:
3266         unregister_syscore_ops(&kvm_syscore_ops);
3267         misc_deregister(&kvm_dev);
3268 out_unreg:
3269         kvm_async_pf_deinit();
3270 out_free:
3271         kmem_cache_destroy(kvm_vcpu_cache);
3272 out_free_3:
3273         unregister_reboot_notifier(&kvm_reboot_notifier);
3274         unregister_cpu_notifier(&kvm_cpu_notifier);
3275 out_free_2:
3276 out_free_1:
3277         kvm_arch_hardware_unsetup();
3278 out_free_0a:
3279         free_cpumask_var(cpus_hardware_enabled);
3280 out_free_0:
3281         kvm_irqfd_exit();
3282 out_irqfd:
3283         kvm_arch_exit();
3284 out_fail:
3285         return r;
3286 }
3287 EXPORT_SYMBOL_GPL(kvm_init);
3288
3289 void kvm_exit(void)
3290 {
3291         kvm_exit_debug();
3292         misc_deregister(&kvm_dev);
3293         kmem_cache_destroy(kvm_vcpu_cache);
3294         kvm_async_pf_deinit();
3295         unregister_syscore_ops(&kvm_syscore_ops);
3296         unregister_reboot_notifier(&kvm_reboot_notifier);
3297         unregister_cpu_notifier(&kvm_cpu_notifier);
3298         on_each_cpu(hardware_disable_nolock, NULL, 1);
3299         kvm_arch_hardware_unsetup();
3300         kvm_arch_exit();
3301         kvm_irqfd_exit();
3302         free_cpumask_var(cpus_hardware_enabled);
3303 }
3304 EXPORT_SYMBOL_GPL(kvm_exit);