vfs: make it possible to access the dentry hash/len as one 64-bit entry
[linux-3.10.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 static struct page *hwpoison_page;
104 static pfn_t hwpoison_pfn;
105
106 struct page *fault_page;
107 pfn_t fault_pfn;
108
109 inline int kvm_is_mmio_pfn(pfn_t pfn)
110 {
111         if (pfn_valid(pfn)) {
112                 int reserved;
113                 struct page *tail = pfn_to_page(pfn);
114                 struct page *head = compound_trans_head(tail);
115                 reserved = PageReserved(head);
116                 if (head != tail) {
117                         /*
118                          * "head" is not a dangling pointer
119                          * (compound_trans_head takes care of that)
120                          * but the hugepage may have been splitted
121                          * from under us (and we may not hold a
122                          * reference count on the head page so it can
123                          * be reused before we run PageReferenced), so
124                          * we've to check PageTail before returning
125                          * what we just read.
126                          */
127                         smp_rmb();
128                         if (PageTail(tail))
129                                 return reserved;
130                 }
131                 return PageReserved(tail);
132         }
133
134         return true;
135 }
136
137 /*
138  * Switches to specified vcpu, until a matching vcpu_put()
139  */
140 void vcpu_load(struct kvm_vcpu *vcpu)
141 {
142         int cpu;
143
144         mutex_lock(&vcpu->mutex);
145         if (unlikely(vcpu->pid != current->pids[PIDTYPE_PID].pid)) {
146                 /* The thread running this VCPU changed. */
147                 struct pid *oldpid = vcpu->pid;
148                 struct pid *newpid = get_task_pid(current, PIDTYPE_PID);
149                 rcu_assign_pointer(vcpu->pid, newpid);
150                 synchronize_rcu();
151                 put_pid(oldpid);
152         }
153         cpu = get_cpu();
154         preempt_notifier_register(&vcpu->preempt_notifier);
155         kvm_arch_vcpu_load(vcpu, cpu);
156         put_cpu();
157 }
158
159 void vcpu_put(struct kvm_vcpu *vcpu)
160 {
161         preempt_disable();
162         kvm_arch_vcpu_put(vcpu);
163         preempt_notifier_unregister(&vcpu->preempt_notifier);
164         preempt_enable();
165         mutex_unlock(&vcpu->mutex);
166 }
167
168 static void ack_flush(void *_completed)
169 {
170 }
171
172 static bool make_all_cpus_request(struct kvm *kvm, unsigned int req)
173 {
174         int i, cpu, me;
175         cpumask_var_t cpus;
176         bool called = true;
177         struct kvm_vcpu *vcpu;
178
179         zalloc_cpumask_var(&cpus, GFP_ATOMIC);
180
181         me = get_cpu();
182         kvm_for_each_vcpu(i, vcpu, kvm) {
183                 kvm_make_request(req, vcpu);
184                 cpu = vcpu->cpu;
185
186                 /* Set ->requests bit before we read ->mode */
187                 smp_mb();
188
189                 if (cpus != NULL && cpu != -1 && cpu != me &&
190                       kvm_vcpu_exiting_guest_mode(vcpu) != OUTSIDE_GUEST_MODE)
191                         cpumask_set_cpu(cpu, cpus);
192         }
193         if (unlikely(cpus == NULL))
194                 smp_call_function_many(cpu_online_mask, ack_flush, NULL, 1);
195         else if (!cpumask_empty(cpus))
196                 smp_call_function_many(cpus, ack_flush, NULL, 1);
197         else
198                 called = false;
199         put_cpu();
200         free_cpumask_var(cpus);
201         return called;
202 }
203
204 void kvm_flush_remote_tlbs(struct kvm *kvm)
205 {
206         long dirty_count = kvm->tlbs_dirty;
207
208         smp_mb();
209         if (make_all_cpus_request(kvm, KVM_REQ_TLB_FLUSH))
210                 ++kvm->stat.remote_tlb_flush;
211         cmpxchg(&kvm->tlbs_dirty, dirty_count, 0);
212 }
213
214 void kvm_reload_remote_mmus(struct kvm *kvm)
215 {
216         make_all_cpus_request(kvm, KVM_REQ_MMU_RELOAD);
217 }
218
219 int kvm_vcpu_init(struct kvm_vcpu *vcpu, struct kvm *kvm, unsigned id)
220 {
221         struct page *page;
222         int r;
223
224         mutex_init(&vcpu->mutex);
225         vcpu->cpu = -1;
226         vcpu->kvm = kvm;
227         vcpu->vcpu_id = id;
228         vcpu->pid = NULL;
229         init_waitqueue_head(&vcpu->wq);
230         kvm_async_pf_vcpu_init(vcpu);
231
232         page = alloc_page(GFP_KERNEL | __GFP_ZERO);
233         if (!page) {
234                 r = -ENOMEM;
235                 goto fail;
236         }
237         vcpu->run = page_address(page);
238
239         r = kvm_arch_vcpu_init(vcpu);
240         if (r < 0)
241                 goto fail_free_run;
242         return 0;
243
244 fail_free_run:
245         free_page((unsigned long)vcpu->run);
246 fail:
247         return r;
248 }
249 EXPORT_SYMBOL_GPL(kvm_vcpu_init);
250
251 void kvm_vcpu_uninit(struct kvm_vcpu *vcpu)
252 {
253         put_pid(vcpu->pid);
254         kvm_arch_vcpu_uninit(vcpu);
255         free_page((unsigned long)vcpu->run);
256 }
257 EXPORT_SYMBOL_GPL(kvm_vcpu_uninit);
258
259 #if defined(CONFIG_MMU_NOTIFIER) && defined(KVM_ARCH_WANT_MMU_NOTIFIER)
260 static inline struct kvm *mmu_notifier_to_kvm(struct mmu_notifier *mn)
261 {
262         return container_of(mn, struct kvm, mmu_notifier);
263 }
264
265 static void kvm_mmu_notifier_invalidate_page(struct mmu_notifier *mn,
266                                              struct mm_struct *mm,
267                                              unsigned long address)
268 {
269         struct kvm *kvm = mmu_notifier_to_kvm(mn);
270         int need_tlb_flush, idx;
271
272         /*
273          * When ->invalidate_page runs, the linux pte has been zapped
274          * already but the page is still allocated until
275          * ->invalidate_page returns. So if we increase the sequence
276          * here the kvm page fault will notice if the spte can't be
277          * established because the page is going to be freed. If
278          * instead the kvm page fault establishes the spte before
279          * ->invalidate_page runs, kvm_unmap_hva will release it
280          * before returning.
281          *
282          * The sequence increase only need to be seen at spin_unlock
283          * time, and not at spin_lock time.
284          *
285          * Increasing the sequence after the spin_unlock would be
286          * unsafe because the kvm page fault could then establish the
287          * pte after kvm_unmap_hva returned, without noticing the page
288          * is going to be freed.
289          */
290         idx = srcu_read_lock(&kvm->srcu);
291         spin_lock(&kvm->mmu_lock);
292
293         kvm->mmu_notifier_seq++;
294         need_tlb_flush = kvm_unmap_hva(kvm, address) | kvm->tlbs_dirty;
295         /* we've to flush the tlb before the pages can be freed */
296         if (need_tlb_flush)
297                 kvm_flush_remote_tlbs(kvm);
298
299         spin_unlock(&kvm->mmu_lock);
300         srcu_read_unlock(&kvm->srcu, idx);
301 }
302
303 static void kvm_mmu_notifier_change_pte(struct mmu_notifier *mn,
304                                         struct mm_struct *mm,
305                                         unsigned long address,
306                                         pte_t pte)
307 {
308         struct kvm *kvm = mmu_notifier_to_kvm(mn);
309         int idx;
310
311         idx = srcu_read_lock(&kvm->srcu);
312         spin_lock(&kvm->mmu_lock);
313         kvm->mmu_notifier_seq++;
314         kvm_set_spte_hva(kvm, address, pte);
315         spin_unlock(&kvm->mmu_lock);
316         srcu_read_unlock(&kvm->srcu, idx);
317 }
318
319 static void kvm_mmu_notifier_invalidate_range_start(struct mmu_notifier *mn,
320                                                     struct mm_struct *mm,
321                                                     unsigned long start,
322                                                     unsigned long end)
323 {
324         struct kvm *kvm = mmu_notifier_to_kvm(mn);
325         int need_tlb_flush = 0, idx;
326
327         idx = srcu_read_lock(&kvm->srcu);
328         spin_lock(&kvm->mmu_lock);
329         /*
330          * The count increase must become visible at unlock time as no
331          * spte can be established without taking the mmu_lock and
332          * count is also read inside the mmu_lock critical section.
333          */
334         kvm->mmu_notifier_count++;
335         for (; start < end; start += PAGE_SIZE)
336                 need_tlb_flush |= kvm_unmap_hva(kvm, start);
337         need_tlb_flush |= kvm->tlbs_dirty;
338         /* we've to flush the tlb before the pages can be freed */
339         if (need_tlb_flush)
340                 kvm_flush_remote_tlbs(kvm);
341
342         spin_unlock(&kvm->mmu_lock);
343         srcu_read_unlock(&kvm->srcu, idx);
344 }
345
346 static void kvm_mmu_notifier_invalidate_range_end(struct mmu_notifier *mn,
347                                                   struct mm_struct *mm,
348                                                   unsigned long start,
349                                                   unsigned long end)
350 {
351         struct kvm *kvm = mmu_notifier_to_kvm(mn);
352
353         spin_lock(&kvm->mmu_lock);
354         /*
355          * This sequence increase will notify the kvm page fault that
356          * the page that is going to be mapped in the spte could have
357          * been freed.
358          */
359         kvm->mmu_notifier_seq++;
360         smp_wmb();
361         /*
362          * The above sequence increase must be visible before the
363          * below count decrease, which is ensured by the smp_wmb above
364          * in conjunction with the smp_rmb in mmu_notifier_retry().
365          */
366         kvm->mmu_notifier_count--;
367         spin_unlock(&kvm->mmu_lock);
368
369         BUG_ON(kvm->mmu_notifier_count < 0);
370 }
371
372 static int kvm_mmu_notifier_clear_flush_young(struct mmu_notifier *mn,
373                                               struct mm_struct *mm,
374                                               unsigned long address)
375 {
376         struct kvm *kvm = mmu_notifier_to_kvm(mn);
377         int young, idx;
378
379         idx = srcu_read_lock(&kvm->srcu);
380         spin_lock(&kvm->mmu_lock);
381
382         young = kvm_age_hva(kvm, address);
383         if (young)
384                 kvm_flush_remote_tlbs(kvm);
385
386         spin_unlock(&kvm->mmu_lock);
387         srcu_read_unlock(&kvm->srcu, idx);
388
389         return young;
390 }
391
392 static int kvm_mmu_notifier_test_young(struct mmu_notifier *mn,
393                                        struct mm_struct *mm,
394                                        unsigned long address)
395 {
396         struct kvm *kvm = mmu_notifier_to_kvm(mn);
397         int young, idx;
398
399         idx = srcu_read_lock(&kvm->srcu);
400         spin_lock(&kvm->mmu_lock);
401         young = kvm_test_age_hva(kvm, address);
402         spin_unlock(&kvm->mmu_lock);
403         srcu_read_unlock(&kvm->srcu, idx);
404
405         return young;
406 }
407
408 static void kvm_mmu_notifier_release(struct mmu_notifier *mn,
409                                      struct mm_struct *mm)
410 {
411         struct kvm *kvm = mmu_notifier_to_kvm(mn);
412         int idx;
413
414         idx = srcu_read_lock(&kvm->srcu);
415         kvm_arch_flush_shadow(kvm);
416         srcu_read_unlock(&kvm->srcu, idx);
417 }
418
419 static const struct mmu_notifier_ops kvm_mmu_notifier_ops = {
420         .invalidate_page        = kvm_mmu_notifier_invalidate_page,
421         .invalidate_range_start = kvm_mmu_notifier_invalidate_range_start,
422         .invalidate_range_end   = kvm_mmu_notifier_invalidate_range_end,
423         .clear_flush_young      = kvm_mmu_notifier_clear_flush_young,
424         .test_young             = kvm_mmu_notifier_test_young,
425         .change_pte             = kvm_mmu_notifier_change_pte,
426         .release                = kvm_mmu_notifier_release,
427 };
428
429 static int kvm_init_mmu_notifier(struct kvm *kvm)
430 {
431         kvm->mmu_notifier.ops = &kvm_mmu_notifier_ops;
432         return mmu_notifier_register(&kvm->mmu_notifier, current->mm);
433 }
434
435 #else  /* !(CONFIG_MMU_NOTIFIER && KVM_ARCH_WANT_MMU_NOTIFIER) */
436
437 static int kvm_init_mmu_notifier(struct kvm *kvm)
438 {
439         return 0;
440 }
441
442 #endif /* CONFIG_MMU_NOTIFIER && KVM_ARCH_WANT_MMU_NOTIFIER */
443
444 static void kvm_init_memslots_id(struct kvm *kvm)
445 {
446         int i;
447         struct kvm_memslots *slots = kvm->memslots;
448
449         for (i = 0; i < KVM_MEM_SLOTS_NUM; i++)
450                 slots->id_to_index[i] = slots->memslots[i].id = i;
451 }
452
453 static struct kvm *kvm_create_vm(unsigned long type)
454 {
455         int r, i;
456         struct kvm *kvm = kvm_arch_alloc_vm();
457
458         if (!kvm)
459                 return ERR_PTR(-ENOMEM);
460
461         r = kvm_arch_init_vm(kvm, type);
462         if (r)
463                 goto out_err_nodisable;
464
465         r = hardware_enable_all();
466         if (r)
467                 goto out_err_nodisable;
468
469 #ifdef CONFIG_HAVE_KVM_IRQCHIP
470         INIT_HLIST_HEAD(&kvm->mask_notifier_list);
471         INIT_HLIST_HEAD(&kvm->irq_ack_notifier_list);
472 #endif
473
474         r = -ENOMEM;
475         kvm->memslots = kzalloc(sizeof(struct kvm_memslots), GFP_KERNEL);
476         if (!kvm->memslots)
477                 goto out_err_nosrcu;
478         kvm_init_memslots_id(kvm);
479         if (init_srcu_struct(&kvm->srcu))
480                 goto out_err_nosrcu;
481         for (i = 0; i < KVM_NR_BUSES; i++) {
482                 kvm->buses[i] = kzalloc(sizeof(struct kvm_io_bus),
483                                         GFP_KERNEL);
484                 if (!kvm->buses[i])
485                         goto out_err;
486         }
487
488         spin_lock_init(&kvm->mmu_lock);
489         kvm->mm = current->mm;
490         atomic_inc(&kvm->mm->mm_count);
491         kvm_eventfd_init(kvm);
492         mutex_init(&kvm->lock);
493         mutex_init(&kvm->irq_lock);
494         mutex_init(&kvm->slots_lock);
495         atomic_set(&kvm->users_count, 1);
496
497         r = kvm_init_mmu_notifier(kvm);
498         if (r)
499                 goto out_err;
500
501         raw_spin_lock(&kvm_lock);
502         list_add(&kvm->vm_list, &vm_list);
503         raw_spin_unlock(&kvm_lock);
504
505         return kvm;
506
507 out_err:
508         cleanup_srcu_struct(&kvm->srcu);
509 out_err_nosrcu:
510         hardware_disable_all();
511 out_err_nodisable:
512         for (i = 0; i < KVM_NR_BUSES; i++)
513                 kfree(kvm->buses[i]);
514         kfree(kvm->memslots);
515         kvm_arch_free_vm(kvm);
516         return ERR_PTR(r);
517 }
518
519 static void kvm_destroy_dirty_bitmap(struct kvm_memory_slot *memslot)
520 {
521         if (!memslot->dirty_bitmap)
522                 return;
523
524         if (2 * kvm_dirty_bitmap_bytes(memslot) > PAGE_SIZE)
525                 vfree(memslot->dirty_bitmap_head);
526         else
527                 kfree(memslot->dirty_bitmap_head);
528
529         memslot->dirty_bitmap = NULL;
530         memslot->dirty_bitmap_head = NULL;
531 }
532
533 /*
534  * Free any memory in @free but not in @dont.
535  */
536 static void kvm_free_physmem_slot(struct kvm_memory_slot *free,
537                                   struct kvm_memory_slot *dont)
538 {
539         if (!dont || free->rmap != dont->rmap)
540                 vfree(free->rmap);
541
542         if (!dont || free->dirty_bitmap != dont->dirty_bitmap)
543                 kvm_destroy_dirty_bitmap(free);
544
545         kvm_arch_free_memslot(free, dont);
546
547         free->npages = 0;
548         free->rmap = NULL;
549 }
550
551 void kvm_free_physmem(struct kvm *kvm)
552 {
553         struct kvm_memslots *slots = kvm->memslots;
554         struct kvm_memory_slot *memslot;
555
556         kvm_for_each_memslot(memslot, slots)
557                 kvm_free_physmem_slot(memslot, NULL);
558
559         kfree(kvm->memslots);
560 }
561
562 static void kvm_destroy_vm(struct kvm *kvm)
563 {
564         int i;
565         struct mm_struct *mm = kvm->mm;
566
567         kvm_arch_sync_events(kvm);
568         raw_spin_lock(&kvm_lock);
569         list_del(&kvm->vm_list);
570         raw_spin_unlock(&kvm_lock);
571         kvm_free_irq_routing(kvm);
572         for (i = 0; i < KVM_NR_BUSES; i++)
573                 kvm_io_bus_destroy(kvm->buses[i]);
574         kvm_coalesced_mmio_free(kvm);
575 #if defined(CONFIG_MMU_NOTIFIER) && defined(KVM_ARCH_WANT_MMU_NOTIFIER)
576         mmu_notifier_unregister(&kvm->mmu_notifier, kvm->mm);
577 #else
578         kvm_arch_flush_shadow(kvm);
579 #endif
580         kvm_arch_destroy_vm(kvm);
581         kvm_free_physmem(kvm);
582         cleanup_srcu_struct(&kvm->srcu);
583         kvm_arch_free_vm(kvm);
584         hardware_disable_all();
585         mmdrop(mm);
586 }
587
588 void kvm_get_kvm(struct kvm *kvm)
589 {
590         atomic_inc(&kvm->users_count);
591 }
592 EXPORT_SYMBOL_GPL(kvm_get_kvm);
593
594 void kvm_put_kvm(struct kvm *kvm)
595 {
596         if (atomic_dec_and_test(&kvm->users_count))
597                 kvm_destroy_vm(kvm);
598 }
599 EXPORT_SYMBOL_GPL(kvm_put_kvm);
600
601
602 static int kvm_vm_release(struct inode *inode, struct file *filp)
603 {
604         struct kvm *kvm = filp->private_data;
605
606         kvm_irqfd_release(kvm);
607
608         kvm_put_kvm(kvm);
609         return 0;
610 }
611
612 /*
613  * Allocation size is twice as large as the actual dirty bitmap size.
614  * This makes it possible to do double buffering: see x86's
615  * kvm_vm_ioctl_get_dirty_log().
616  */
617 static int kvm_create_dirty_bitmap(struct kvm_memory_slot *memslot)
618 {
619 #ifndef CONFIG_S390
620         unsigned long dirty_bytes = 2 * kvm_dirty_bitmap_bytes(memslot);
621
622         if (dirty_bytes > PAGE_SIZE)
623                 memslot->dirty_bitmap = vzalloc(dirty_bytes);
624         else
625                 memslot->dirty_bitmap = kzalloc(dirty_bytes, GFP_KERNEL);
626
627         if (!memslot->dirty_bitmap)
628                 return -ENOMEM;
629
630         memslot->dirty_bitmap_head = memslot->dirty_bitmap;
631         memslot->nr_dirty_pages = 0;
632 #endif /* !CONFIG_S390 */
633         return 0;
634 }
635
636 static int cmp_memslot(const void *slot1, const void *slot2)
637 {
638         struct kvm_memory_slot *s1, *s2;
639
640         s1 = (struct kvm_memory_slot *)slot1;
641         s2 = (struct kvm_memory_slot *)slot2;
642
643         if (s1->npages < s2->npages)
644                 return 1;
645         if (s1->npages > s2->npages)
646                 return -1;
647
648         return 0;
649 }
650
651 /*
652  * Sort the memslots base on its size, so the larger slots
653  * will get better fit.
654  */
655 static void sort_memslots(struct kvm_memslots *slots)
656 {
657         int i;
658
659         sort(slots->memslots, KVM_MEM_SLOTS_NUM,
660               sizeof(struct kvm_memory_slot), cmp_memslot, NULL);
661
662         for (i = 0; i < KVM_MEM_SLOTS_NUM; i++)
663                 slots->id_to_index[slots->memslots[i].id] = i;
664 }
665
666 void update_memslots(struct kvm_memslots *slots, struct kvm_memory_slot *new)
667 {
668         if (new) {
669                 int id = new->id;
670                 struct kvm_memory_slot *old = id_to_memslot(slots, id);
671                 unsigned long npages = old->npages;
672
673                 *old = *new;
674                 if (new->npages != npages)
675                         sort_memslots(slots);
676         }
677
678         slots->generation++;
679 }
680
681 /*
682  * Allocate some memory and give it an address in the guest physical address
683  * space.
684  *
685  * Discontiguous memory is allowed, mostly for framebuffers.
686  *
687  * Must be called holding mmap_sem for write.
688  */
689 int __kvm_set_memory_region(struct kvm *kvm,
690                             struct kvm_userspace_memory_region *mem,
691                             int user_alloc)
692 {
693         int r;
694         gfn_t base_gfn;
695         unsigned long npages;
696         unsigned long i;
697         struct kvm_memory_slot *memslot;
698         struct kvm_memory_slot old, new;
699         struct kvm_memslots *slots, *old_memslots;
700
701         r = -EINVAL;
702         /* General sanity checks */
703         if (mem->memory_size & (PAGE_SIZE - 1))
704                 goto out;
705         if (mem->guest_phys_addr & (PAGE_SIZE - 1))
706                 goto out;
707         /* We can read the guest memory with __xxx_user() later on. */
708         if (user_alloc &&
709             ((mem->userspace_addr & (PAGE_SIZE - 1)) ||
710              !access_ok(VERIFY_WRITE,
711                         (void __user *)(unsigned long)mem->userspace_addr,
712                         mem->memory_size)))
713                 goto out;
714         if (mem->slot >= KVM_MEM_SLOTS_NUM)
715                 goto out;
716         if (mem->guest_phys_addr + mem->memory_size < mem->guest_phys_addr)
717                 goto out;
718
719         memslot = id_to_memslot(kvm->memslots, mem->slot);
720         base_gfn = mem->guest_phys_addr >> PAGE_SHIFT;
721         npages = mem->memory_size >> PAGE_SHIFT;
722
723         r = -EINVAL;
724         if (npages > KVM_MEM_MAX_NR_PAGES)
725                 goto out;
726
727         if (!npages)
728                 mem->flags &= ~KVM_MEM_LOG_DIRTY_PAGES;
729
730         new = old = *memslot;
731
732         new.id = mem->slot;
733         new.base_gfn = base_gfn;
734         new.npages = npages;
735         new.flags = mem->flags;
736
737         /* Disallow changing a memory slot's size. */
738         r = -EINVAL;
739         if (npages && old.npages && npages != old.npages)
740                 goto out_free;
741
742         /* Check for overlaps */
743         r = -EEXIST;
744         for (i = 0; i < KVM_MEMORY_SLOTS; ++i) {
745                 struct kvm_memory_slot *s = &kvm->memslots->memslots[i];
746
747                 if (s == memslot || !s->npages)
748                         continue;
749                 if (!((base_gfn + npages <= s->base_gfn) ||
750                       (base_gfn >= s->base_gfn + s->npages)))
751                         goto out_free;
752         }
753
754         /* Free page dirty bitmap if unneeded */
755         if (!(new.flags & KVM_MEM_LOG_DIRTY_PAGES))
756                 new.dirty_bitmap = NULL;
757
758         r = -ENOMEM;
759
760         /* Allocate if a slot is being created */
761         if (npages && !old.npages) {
762                 new.user_alloc = user_alloc;
763                 new.userspace_addr = mem->userspace_addr;
764 #ifndef CONFIG_S390
765                 new.rmap = vzalloc(npages * sizeof(*new.rmap));
766                 if (!new.rmap)
767                         goto out_free;
768 #endif /* not defined CONFIG_S390 */
769                 if (kvm_arch_create_memslot(&new, npages))
770                         goto out_free;
771         }
772
773         /* Allocate page dirty bitmap if needed */
774         if ((new.flags & KVM_MEM_LOG_DIRTY_PAGES) && !new.dirty_bitmap) {
775                 if (kvm_create_dirty_bitmap(&new) < 0)
776                         goto out_free;
777                 /* destroy any largepage mappings for dirty tracking */
778         }
779
780         if (!npages) {
781                 struct kvm_memory_slot *slot;
782
783                 r = -ENOMEM;
784                 slots = kmemdup(kvm->memslots, sizeof(struct kvm_memslots),
785                                 GFP_KERNEL);
786                 if (!slots)
787                         goto out_free;
788                 slot = id_to_memslot(slots, mem->slot);
789                 slot->flags |= KVM_MEMSLOT_INVALID;
790
791                 update_memslots(slots, NULL);
792
793                 old_memslots = kvm->memslots;
794                 rcu_assign_pointer(kvm->memslots, slots);
795                 synchronize_srcu_expedited(&kvm->srcu);
796                 /* From this point no new shadow pages pointing to a deleted
797                  * memslot will be created.
798                  *
799                  * validation of sp->gfn happens in:
800                  *      - gfn_to_hva (kvm_read_guest, gfn_to_pfn)
801                  *      - kvm_is_visible_gfn (mmu_check_roots)
802                  */
803                 kvm_arch_flush_shadow(kvm);
804                 kfree(old_memslots);
805         }
806
807         r = kvm_arch_prepare_memory_region(kvm, &new, old, mem, user_alloc);
808         if (r)
809                 goto out_free;
810
811         /* map/unmap the pages in iommu page table */
812         if (npages) {
813                 r = kvm_iommu_map_pages(kvm, &new);
814                 if (r)
815                         goto out_free;
816         } else
817                 kvm_iommu_unmap_pages(kvm, &old);
818
819         r = -ENOMEM;
820         slots = kmemdup(kvm->memslots, sizeof(struct kvm_memslots),
821                         GFP_KERNEL);
822         if (!slots)
823                 goto out_free;
824
825         /* actual memory is freed via old in kvm_free_physmem_slot below */
826         if (!npages) {
827                 new.rmap = NULL;
828                 new.dirty_bitmap = NULL;
829                 memset(&new.arch, 0, sizeof(new.arch));
830         }
831
832         update_memslots(slots, &new);
833         old_memslots = kvm->memslots;
834         rcu_assign_pointer(kvm->memslots, slots);
835         synchronize_srcu_expedited(&kvm->srcu);
836
837         kvm_arch_commit_memory_region(kvm, mem, old, user_alloc);
838
839         /*
840          * If the new memory slot is created, we need to clear all
841          * mmio sptes.
842          */
843         if (npages && old.base_gfn != mem->guest_phys_addr >> PAGE_SHIFT)
844                 kvm_arch_flush_shadow(kvm);
845
846         kvm_free_physmem_slot(&old, &new);
847         kfree(old_memslots);
848
849         return 0;
850
851 out_free:
852         kvm_free_physmem_slot(&new, &old);
853 out:
854         return r;
855
856 }
857 EXPORT_SYMBOL_GPL(__kvm_set_memory_region);
858
859 int kvm_set_memory_region(struct kvm *kvm,
860                           struct kvm_userspace_memory_region *mem,
861                           int user_alloc)
862 {
863         int r;
864
865         mutex_lock(&kvm->slots_lock);
866         r = __kvm_set_memory_region(kvm, mem, user_alloc);
867         mutex_unlock(&kvm->slots_lock);
868         return r;
869 }
870 EXPORT_SYMBOL_GPL(kvm_set_memory_region);
871
872 int kvm_vm_ioctl_set_memory_region(struct kvm *kvm,
873                                    struct
874                                    kvm_userspace_memory_region *mem,
875                                    int user_alloc)
876 {
877         if (mem->slot >= KVM_MEMORY_SLOTS)
878                 return -EINVAL;
879         return kvm_set_memory_region(kvm, mem, user_alloc);
880 }
881
882 int kvm_get_dirty_log(struct kvm *kvm,
883                         struct kvm_dirty_log *log, int *is_dirty)
884 {
885         struct kvm_memory_slot *memslot;
886         int r, i;
887         unsigned long n;
888         unsigned long any = 0;
889
890         r = -EINVAL;
891         if (log->slot >= KVM_MEMORY_SLOTS)
892                 goto out;
893
894         memslot = id_to_memslot(kvm->memslots, log->slot);
895         r = -ENOENT;
896         if (!memslot->dirty_bitmap)
897                 goto out;
898
899         n = kvm_dirty_bitmap_bytes(memslot);
900
901         for (i = 0; !any && i < n/sizeof(long); ++i)
902                 any = memslot->dirty_bitmap[i];
903
904         r = -EFAULT;
905         if (copy_to_user(log->dirty_bitmap, memslot->dirty_bitmap, n))
906                 goto out;
907
908         if (any)
909                 *is_dirty = 1;
910
911         r = 0;
912 out:
913         return r;
914 }
915
916 bool kvm_largepages_enabled(void)
917 {
918         return largepages_enabled;
919 }
920
921 void kvm_disable_largepages(void)
922 {
923         largepages_enabled = false;
924 }
925 EXPORT_SYMBOL_GPL(kvm_disable_largepages);
926
927 int is_error_page(struct page *page)
928 {
929         return page == bad_page || page == hwpoison_page || page == fault_page;
930 }
931 EXPORT_SYMBOL_GPL(is_error_page);
932
933 int is_error_pfn(pfn_t pfn)
934 {
935         return pfn == bad_pfn || pfn == hwpoison_pfn || pfn == fault_pfn;
936 }
937 EXPORT_SYMBOL_GPL(is_error_pfn);
938
939 int is_hwpoison_pfn(pfn_t pfn)
940 {
941         return pfn == hwpoison_pfn;
942 }
943 EXPORT_SYMBOL_GPL(is_hwpoison_pfn);
944
945 int is_fault_pfn(pfn_t pfn)
946 {
947         return pfn == fault_pfn;
948 }
949 EXPORT_SYMBOL_GPL(is_fault_pfn);
950
951 int is_noslot_pfn(pfn_t pfn)
952 {
953         return pfn == bad_pfn;
954 }
955 EXPORT_SYMBOL_GPL(is_noslot_pfn);
956
957 int is_invalid_pfn(pfn_t pfn)
958 {
959         return pfn == hwpoison_pfn || pfn == fault_pfn;
960 }
961 EXPORT_SYMBOL_GPL(is_invalid_pfn);
962
963 static inline unsigned long bad_hva(void)
964 {
965         return PAGE_OFFSET;
966 }
967
968 int kvm_is_error_hva(unsigned long addr)
969 {
970         return addr == bad_hva();
971 }
972 EXPORT_SYMBOL_GPL(kvm_is_error_hva);
973
974 struct kvm_memory_slot *gfn_to_memslot(struct kvm *kvm, gfn_t gfn)
975 {
976         return __gfn_to_memslot(kvm_memslots(kvm), gfn);
977 }
978 EXPORT_SYMBOL_GPL(gfn_to_memslot);
979
980 int kvm_is_visible_gfn(struct kvm *kvm, gfn_t gfn)
981 {
982         struct kvm_memory_slot *memslot = gfn_to_memslot(kvm, gfn);
983
984         if (!memslot || memslot->id >= KVM_MEMORY_SLOTS ||
985               memslot->flags & KVM_MEMSLOT_INVALID)
986                 return 0;
987
988         return 1;
989 }
990 EXPORT_SYMBOL_GPL(kvm_is_visible_gfn);
991
992 unsigned long kvm_host_page_size(struct kvm *kvm, gfn_t gfn)
993 {
994         struct vm_area_struct *vma;
995         unsigned long addr, size;
996
997         size = PAGE_SIZE;
998
999         addr = gfn_to_hva(kvm, gfn);
1000         if (kvm_is_error_hva(addr))
1001                 return PAGE_SIZE;
1002
1003         down_read(&current->mm->mmap_sem);
1004         vma = find_vma(current->mm, addr);
1005         if (!vma)
1006                 goto out;
1007
1008         size = vma_kernel_pagesize(vma);
1009
1010 out:
1011         up_read(&current->mm->mmap_sem);
1012
1013         return size;
1014 }
1015
1016 static unsigned long gfn_to_hva_many(struct kvm_memory_slot *slot, gfn_t gfn,
1017                                      gfn_t *nr_pages)
1018 {
1019         if (!slot || slot->flags & KVM_MEMSLOT_INVALID)
1020                 return bad_hva();
1021
1022         if (nr_pages)
1023                 *nr_pages = slot->npages - (gfn - slot->base_gfn);
1024
1025         return gfn_to_hva_memslot(slot, gfn);
1026 }
1027
1028 unsigned long gfn_to_hva(struct kvm *kvm, gfn_t gfn)
1029 {
1030         return gfn_to_hva_many(gfn_to_memslot(kvm, gfn), gfn, NULL);
1031 }
1032 EXPORT_SYMBOL_GPL(gfn_to_hva);
1033
1034 static pfn_t get_fault_pfn(void)
1035 {
1036         get_page(fault_page);
1037         return fault_pfn;
1038 }
1039
1040 int get_user_page_nowait(struct task_struct *tsk, struct mm_struct *mm,
1041         unsigned long start, int write, struct page **page)
1042 {
1043         int flags = FOLL_TOUCH | FOLL_NOWAIT | FOLL_HWPOISON | FOLL_GET;
1044
1045         if (write)
1046                 flags |= FOLL_WRITE;
1047
1048         return __get_user_pages(tsk, mm, start, 1, flags, page, NULL, NULL);
1049 }
1050
1051 static inline int check_user_page_hwpoison(unsigned long addr)
1052 {
1053         int rc, flags = FOLL_TOUCH | FOLL_HWPOISON | FOLL_WRITE;
1054
1055         rc = __get_user_pages(current, current->mm, addr, 1,
1056                               flags, NULL, NULL, NULL);
1057         return rc == -EHWPOISON;
1058 }
1059
1060 static pfn_t hva_to_pfn(struct kvm *kvm, unsigned long addr, bool atomic,
1061                         bool *async, bool write_fault, bool *writable)
1062 {
1063         struct page *page[1];
1064         int npages = 0;
1065         pfn_t pfn;
1066
1067         /* we can do it either atomically or asynchronously, not both */
1068         BUG_ON(atomic && async);
1069
1070         BUG_ON(!write_fault && !writable);
1071
1072         if (writable)
1073                 *writable = true;
1074
1075         if (atomic || async)
1076                 npages = __get_user_pages_fast(addr, 1, 1, page);
1077
1078         if (unlikely(npages != 1) && !atomic) {
1079                 might_sleep();
1080
1081                 if (writable)
1082                         *writable = write_fault;
1083
1084                 if (async) {
1085                         down_read(&current->mm->mmap_sem);
1086                         npages = get_user_page_nowait(current, current->mm,
1087                                                      addr, write_fault, page);
1088                         up_read(&current->mm->mmap_sem);
1089                 } else
1090                         npages = get_user_pages_fast(addr, 1, write_fault,
1091                                                      page);
1092
1093                 /* map read fault as writable if possible */
1094                 if (unlikely(!write_fault) && npages == 1) {
1095                         struct page *wpage[1];
1096
1097                         npages = __get_user_pages_fast(addr, 1, 1, wpage);
1098                         if (npages == 1) {
1099                                 *writable = true;
1100                                 put_page(page[0]);
1101                                 page[0] = wpage[0];
1102                         }
1103                         npages = 1;
1104                 }
1105         }
1106
1107         if (unlikely(npages != 1)) {
1108                 struct vm_area_struct *vma;
1109
1110                 if (atomic)
1111                         return get_fault_pfn();
1112
1113                 down_read(&current->mm->mmap_sem);
1114                 if (npages == -EHWPOISON ||
1115                         (!async && check_user_page_hwpoison(addr))) {
1116                         up_read(&current->mm->mmap_sem);
1117                         get_page(hwpoison_page);
1118                         return page_to_pfn(hwpoison_page);
1119                 }
1120
1121                 vma = find_vma_intersection(current->mm, addr, addr+1);
1122
1123                 if (vma == NULL)
1124                         pfn = get_fault_pfn();
1125                 else if ((vma->vm_flags & VM_PFNMAP)) {
1126                         pfn = ((addr - vma->vm_start) >> PAGE_SHIFT) +
1127                                 vma->vm_pgoff;
1128                         BUG_ON(!kvm_is_mmio_pfn(pfn));
1129                 } else {
1130                         if (async && (vma->vm_flags & VM_WRITE))
1131                                 *async = true;
1132                         pfn = get_fault_pfn();
1133                 }
1134                 up_read(&current->mm->mmap_sem);
1135         } else
1136                 pfn = page_to_pfn(page[0]);
1137
1138         return pfn;
1139 }
1140
1141 pfn_t hva_to_pfn_atomic(struct kvm *kvm, unsigned long addr)
1142 {
1143         return hva_to_pfn(kvm, addr, true, NULL, true, NULL);
1144 }
1145 EXPORT_SYMBOL_GPL(hva_to_pfn_atomic);
1146
1147 static pfn_t __gfn_to_pfn(struct kvm *kvm, gfn_t gfn, bool atomic, bool *async,
1148                           bool write_fault, bool *writable)
1149 {
1150         unsigned long addr;
1151
1152         if (async)
1153                 *async = false;
1154
1155         addr = gfn_to_hva(kvm, gfn);
1156         if (kvm_is_error_hva(addr)) {
1157                 get_page(bad_page);
1158                 return page_to_pfn(bad_page);
1159         }
1160
1161         return hva_to_pfn(kvm, addr, atomic, async, write_fault, writable);
1162 }
1163
1164 pfn_t gfn_to_pfn_atomic(struct kvm *kvm, gfn_t gfn)
1165 {
1166         return __gfn_to_pfn(kvm, gfn, true, NULL, true, NULL);
1167 }
1168 EXPORT_SYMBOL_GPL(gfn_to_pfn_atomic);
1169
1170 pfn_t gfn_to_pfn_async(struct kvm *kvm, gfn_t gfn, bool *async,
1171                        bool write_fault, bool *writable)
1172 {
1173         return __gfn_to_pfn(kvm, gfn, false, async, write_fault, writable);
1174 }
1175 EXPORT_SYMBOL_GPL(gfn_to_pfn_async);
1176
1177 pfn_t gfn_to_pfn(struct kvm *kvm, gfn_t gfn)
1178 {
1179         return __gfn_to_pfn(kvm, gfn, false, NULL, true, NULL);
1180 }
1181 EXPORT_SYMBOL_GPL(gfn_to_pfn);
1182
1183 pfn_t gfn_to_pfn_prot(struct kvm *kvm, gfn_t gfn, bool write_fault,
1184                       bool *writable)
1185 {
1186         return __gfn_to_pfn(kvm, gfn, false, NULL, write_fault, writable);
1187 }
1188 EXPORT_SYMBOL_GPL(gfn_to_pfn_prot);
1189
1190 pfn_t gfn_to_pfn_memslot(struct kvm *kvm,
1191                          struct kvm_memory_slot *slot, gfn_t gfn)
1192 {
1193         unsigned long addr = gfn_to_hva_memslot(slot, gfn);
1194         return hva_to_pfn(kvm, addr, false, NULL, true, NULL);
1195 }
1196
1197 int gfn_to_page_many_atomic(struct kvm *kvm, gfn_t gfn, struct page **pages,
1198                                                                   int nr_pages)
1199 {
1200         unsigned long addr;
1201         gfn_t entry;
1202
1203         addr = gfn_to_hva_many(gfn_to_memslot(kvm, gfn), gfn, &entry);
1204         if (kvm_is_error_hva(addr))
1205                 return -1;
1206
1207         if (entry < nr_pages)
1208                 return 0;
1209
1210         return __get_user_pages_fast(addr, nr_pages, 1, pages);
1211 }
1212 EXPORT_SYMBOL_GPL(gfn_to_page_many_atomic);
1213
1214 struct page *gfn_to_page(struct kvm *kvm, gfn_t gfn)
1215 {
1216         pfn_t pfn;
1217
1218         pfn = gfn_to_pfn(kvm, gfn);
1219         if (!kvm_is_mmio_pfn(pfn))
1220                 return pfn_to_page(pfn);
1221
1222         WARN_ON(kvm_is_mmio_pfn(pfn));
1223
1224         get_page(bad_page);
1225         return bad_page;
1226 }
1227
1228 EXPORT_SYMBOL_GPL(gfn_to_page);
1229
1230 void kvm_release_page_clean(struct page *page)
1231 {
1232         kvm_release_pfn_clean(page_to_pfn(page));
1233 }
1234 EXPORT_SYMBOL_GPL(kvm_release_page_clean);
1235
1236 void kvm_release_pfn_clean(pfn_t pfn)
1237 {
1238         if (!kvm_is_mmio_pfn(pfn))
1239                 put_page(pfn_to_page(pfn));
1240 }
1241 EXPORT_SYMBOL_GPL(kvm_release_pfn_clean);
1242
1243 void kvm_release_page_dirty(struct page *page)
1244 {
1245         kvm_release_pfn_dirty(page_to_pfn(page));
1246 }
1247 EXPORT_SYMBOL_GPL(kvm_release_page_dirty);
1248
1249 void kvm_release_pfn_dirty(pfn_t pfn)
1250 {
1251         kvm_set_pfn_dirty(pfn);
1252         kvm_release_pfn_clean(pfn);
1253 }
1254 EXPORT_SYMBOL_GPL(kvm_release_pfn_dirty);
1255
1256 void kvm_set_page_dirty(struct page *page)
1257 {
1258         kvm_set_pfn_dirty(page_to_pfn(page));
1259 }
1260 EXPORT_SYMBOL_GPL(kvm_set_page_dirty);
1261
1262 void kvm_set_pfn_dirty(pfn_t pfn)
1263 {
1264         if (!kvm_is_mmio_pfn(pfn)) {
1265                 struct page *page = pfn_to_page(pfn);
1266                 if (!PageReserved(page))
1267                         SetPageDirty(page);
1268         }
1269 }
1270 EXPORT_SYMBOL_GPL(kvm_set_pfn_dirty);
1271
1272 void kvm_set_pfn_accessed(pfn_t pfn)
1273 {
1274         if (!kvm_is_mmio_pfn(pfn))
1275                 mark_page_accessed(pfn_to_page(pfn));
1276 }
1277 EXPORT_SYMBOL_GPL(kvm_set_pfn_accessed);
1278
1279 void kvm_get_pfn(pfn_t pfn)
1280 {
1281         if (!kvm_is_mmio_pfn(pfn))
1282                 get_page(pfn_to_page(pfn));
1283 }
1284 EXPORT_SYMBOL_GPL(kvm_get_pfn);
1285
1286 static int next_segment(unsigned long len, int offset)
1287 {
1288         if (len > PAGE_SIZE - offset)
1289                 return PAGE_SIZE - offset;
1290         else
1291                 return len;
1292 }
1293
1294 int kvm_read_guest_page(struct kvm *kvm, gfn_t gfn, void *data, int offset,
1295                         int len)
1296 {
1297         int r;
1298         unsigned long addr;
1299
1300         addr = gfn_to_hva(kvm, gfn);
1301         if (kvm_is_error_hva(addr))
1302                 return -EFAULT;
1303         r = __copy_from_user(data, (void __user *)addr + offset, len);
1304         if (r)
1305                 return -EFAULT;
1306         return 0;
1307 }
1308 EXPORT_SYMBOL_GPL(kvm_read_guest_page);
1309
1310 int kvm_read_guest(struct kvm *kvm, gpa_t gpa, void *data, unsigned long len)
1311 {
1312         gfn_t gfn = gpa >> PAGE_SHIFT;
1313         int seg;
1314         int offset = offset_in_page(gpa);
1315         int ret;
1316
1317         while ((seg = next_segment(len, offset)) != 0) {
1318                 ret = kvm_read_guest_page(kvm, gfn, data, offset, seg);
1319                 if (ret < 0)
1320                         return ret;
1321                 offset = 0;
1322                 len -= seg;
1323                 data += seg;
1324                 ++gfn;
1325         }
1326         return 0;
1327 }
1328 EXPORT_SYMBOL_GPL(kvm_read_guest);
1329
1330 int kvm_read_guest_atomic(struct kvm *kvm, gpa_t gpa, void *data,
1331                           unsigned long len)
1332 {
1333         int r;
1334         unsigned long addr;
1335         gfn_t gfn = gpa >> PAGE_SHIFT;
1336         int offset = offset_in_page(gpa);
1337
1338         addr = gfn_to_hva(kvm, gfn);
1339         if (kvm_is_error_hva(addr))
1340                 return -EFAULT;
1341         pagefault_disable();
1342         r = __copy_from_user_inatomic(data, (void __user *)addr + offset, len);
1343         pagefault_enable();
1344         if (r)
1345                 return -EFAULT;
1346         return 0;
1347 }
1348 EXPORT_SYMBOL(kvm_read_guest_atomic);
1349
1350 int kvm_write_guest_page(struct kvm *kvm, gfn_t gfn, const void *data,
1351                          int offset, int len)
1352 {
1353         int r;
1354         unsigned long addr;
1355
1356         addr = gfn_to_hva(kvm, gfn);
1357         if (kvm_is_error_hva(addr))
1358                 return -EFAULT;
1359         r = __copy_to_user((void __user *)addr + offset, data, len);
1360         if (r)
1361                 return -EFAULT;
1362         mark_page_dirty(kvm, gfn);
1363         return 0;
1364 }
1365 EXPORT_SYMBOL_GPL(kvm_write_guest_page);
1366
1367 int kvm_write_guest(struct kvm *kvm, gpa_t gpa, const void *data,
1368                     unsigned long len)
1369 {
1370         gfn_t gfn = gpa >> PAGE_SHIFT;
1371         int seg;
1372         int offset = offset_in_page(gpa);
1373         int ret;
1374
1375         while ((seg = next_segment(len, offset)) != 0) {
1376                 ret = kvm_write_guest_page(kvm, gfn, data, offset, seg);
1377                 if (ret < 0)
1378                         return ret;
1379                 offset = 0;
1380                 len -= seg;
1381                 data += seg;
1382                 ++gfn;
1383         }
1384         return 0;
1385 }
1386
1387 int kvm_gfn_to_hva_cache_init(struct kvm *kvm, struct gfn_to_hva_cache *ghc,
1388                               gpa_t gpa)
1389 {
1390         struct kvm_memslots *slots = kvm_memslots(kvm);
1391         int offset = offset_in_page(gpa);
1392         gfn_t gfn = gpa >> PAGE_SHIFT;
1393
1394         ghc->gpa = gpa;
1395         ghc->generation = slots->generation;
1396         ghc->memslot = gfn_to_memslot(kvm, gfn);
1397         ghc->hva = gfn_to_hva_many(ghc->memslot, gfn, NULL);
1398         if (!kvm_is_error_hva(ghc->hva))
1399                 ghc->hva += offset;
1400         else
1401                 return -EFAULT;
1402
1403         return 0;
1404 }
1405 EXPORT_SYMBOL_GPL(kvm_gfn_to_hva_cache_init);
1406
1407 int kvm_write_guest_cached(struct kvm *kvm, struct gfn_to_hva_cache *ghc,
1408                            void *data, unsigned long len)
1409 {
1410         struct kvm_memslots *slots = kvm_memslots(kvm);
1411         int r;
1412
1413         if (slots->generation != ghc->generation)
1414                 kvm_gfn_to_hva_cache_init(kvm, ghc, ghc->gpa);
1415
1416         if (kvm_is_error_hva(ghc->hva))
1417                 return -EFAULT;
1418
1419         r = __copy_to_user((void __user *)ghc->hva, data, len);
1420         if (r)
1421                 return -EFAULT;
1422         mark_page_dirty_in_slot(kvm, ghc->memslot, ghc->gpa >> PAGE_SHIFT);
1423
1424         return 0;
1425 }
1426 EXPORT_SYMBOL_GPL(kvm_write_guest_cached);
1427
1428 int kvm_read_guest_cached(struct kvm *kvm, struct gfn_to_hva_cache *ghc,
1429                            void *data, unsigned long len)
1430 {
1431         struct kvm_memslots *slots = kvm_memslots(kvm);
1432         int r;
1433
1434         if (slots->generation != ghc->generation)
1435                 kvm_gfn_to_hva_cache_init(kvm, ghc, ghc->gpa);
1436
1437         if (kvm_is_error_hva(ghc->hva))
1438                 return -EFAULT;
1439
1440         r = __copy_from_user(data, (void __user *)ghc->hva, len);
1441         if (r)
1442                 return -EFAULT;
1443
1444         return 0;
1445 }
1446 EXPORT_SYMBOL_GPL(kvm_read_guest_cached);
1447
1448 int kvm_clear_guest_page(struct kvm *kvm, gfn_t gfn, int offset, int len)
1449 {
1450         return kvm_write_guest_page(kvm, gfn, (const void *) empty_zero_page,
1451                                     offset, len);
1452 }
1453 EXPORT_SYMBOL_GPL(kvm_clear_guest_page);
1454
1455 int kvm_clear_guest(struct kvm *kvm, gpa_t gpa, unsigned long len)
1456 {
1457         gfn_t gfn = gpa >> PAGE_SHIFT;
1458         int seg;
1459         int offset = offset_in_page(gpa);
1460         int ret;
1461
1462         while ((seg = next_segment(len, offset)) != 0) {
1463                 ret = kvm_clear_guest_page(kvm, gfn, offset, seg);
1464                 if (ret < 0)
1465                         return ret;
1466                 offset = 0;
1467                 len -= seg;
1468                 ++gfn;
1469         }
1470         return 0;
1471 }
1472 EXPORT_SYMBOL_GPL(kvm_clear_guest);
1473
1474 void mark_page_dirty_in_slot(struct kvm *kvm, struct kvm_memory_slot *memslot,
1475                              gfn_t gfn)
1476 {
1477         if (memslot && memslot->dirty_bitmap) {
1478                 unsigned long rel_gfn = gfn - memslot->base_gfn;
1479
1480                 if (!test_and_set_bit_le(rel_gfn, memslot->dirty_bitmap))
1481                         memslot->nr_dirty_pages++;
1482         }
1483 }
1484
1485 void mark_page_dirty(struct kvm *kvm, gfn_t gfn)
1486 {
1487         struct kvm_memory_slot *memslot;
1488
1489         memslot = gfn_to_memslot(kvm, gfn);
1490         mark_page_dirty_in_slot(kvm, memslot, gfn);
1491 }
1492
1493 /*
1494  * The vCPU has executed a HLT instruction with in-kernel mode enabled.
1495  */
1496 void kvm_vcpu_block(struct kvm_vcpu *vcpu)
1497 {
1498         DEFINE_WAIT(wait);
1499
1500         for (;;) {
1501                 prepare_to_wait(&vcpu->wq, &wait, TASK_INTERRUPTIBLE);
1502
1503                 if (kvm_arch_vcpu_runnable(vcpu)) {
1504                         kvm_make_request(KVM_REQ_UNHALT, vcpu);
1505                         break;
1506                 }
1507                 if (kvm_cpu_has_pending_timer(vcpu))
1508                         break;
1509                 if (signal_pending(current))
1510                         break;
1511
1512                 schedule();
1513         }
1514
1515         finish_wait(&vcpu->wq, &wait);
1516 }
1517
1518 void kvm_resched(struct kvm_vcpu *vcpu)
1519 {
1520         if (!need_resched())
1521                 return;
1522         cond_resched();
1523 }
1524 EXPORT_SYMBOL_GPL(kvm_resched);
1525
1526 void kvm_vcpu_on_spin(struct kvm_vcpu *me)
1527 {
1528         struct kvm *kvm = me->kvm;
1529         struct kvm_vcpu *vcpu;
1530         int last_boosted_vcpu = me->kvm->last_boosted_vcpu;
1531         int yielded = 0;
1532         int pass;
1533         int i;
1534
1535         /*
1536          * We boost the priority of a VCPU that is runnable but not
1537          * currently running, because it got preempted by something
1538          * else and called schedule in __vcpu_run.  Hopefully that
1539          * VCPU is holding the lock that we need and will release it.
1540          * We approximate round-robin by starting at the last boosted VCPU.
1541          */
1542         for (pass = 0; pass < 2 && !yielded; pass++) {
1543                 kvm_for_each_vcpu(i, vcpu, kvm) {
1544                         struct task_struct *task = NULL;
1545                         struct pid *pid;
1546                         if (!pass && i < last_boosted_vcpu) {
1547                                 i = last_boosted_vcpu;
1548                                 continue;
1549                         } else if (pass && i > last_boosted_vcpu)
1550                                 break;
1551                         if (vcpu == me)
1552                                 continue;
1553                         if (waitqueue_active(&vcpu->wq))
1554                                 continue;
1555                         rcu_read_lock();
1556                         pid = rcu_dereference(vcpu->pid);
1557                         if (pid)
1558                                 task = get_pid_task(vcpu->pid, PIDTYPE_PID);
1559                         rcu_read_unlock();
1560                         if (!task)
1561                                 continue;
1562                         if (task->flags & PF_VCPU) {
1563                                 put_task_struct(task);
1564                                 continue;
1565                         }
1566                         if (yield_to(task, 1)) {
1567                                 put_task_struct(task);
1568                                 kvm->last_boosted_vcpu = i;
1569                                 yielded = 1;
1570                                 break;
1571                         }
1572                         put_task_struct(task);
1573                 }
1574         }
1575 }
1576 EXPORT_SYMBOL_GPL(kvm_vcpu_on_spin);
1577
1578 static int kvm_vcpu_fault(struct vm_area_struct *vma, struct vm_fault *vmf)
1579 {
1580         struct kvm_vcpu *vcpu = vma->vm_file->private_data;
1581         struct page *page;
1582
1583         if (vmf->pgoff == 0)
1584                 page = virt_to_page(vcpu->run);
1585 #ifdef CONFIG_X86
1586         else if (vmf->pgoff == KVM_PIO_PAGE_OFFSET)
1587                 page = virt_to_page(vcpu->arch.pio_data);
1588 #endif
1589 #ifdef KVM_COALESCED_MMIO_PAGE_OFFSET
1590         else if (vmf->pgoff == KVM_COALESCED_MMIO_PAGE_OFFSET)
1591                 page = virt_to_page(vcpu->kvm->coalesced_mmio_ring);
1592 #endif
1593         else
1594                 return kvm_arch_vcpu_fault(vcpu, vmf);
1595         get_page(page);
1596         vmf->page = page;
1597         return 0;
1598 }
1599
1600 static const struct vm_operations_struct kvm_vcpu_vm_ops = {
1601         .fault = kvm_vcpu_fault,
1602 };
1603
1604 static int kvm_vcpu_mmap(struct file *file, struct vm_area_struct *vma)
1605 {
1606         vma->vm_ops = &kvm_vcpu_vm_ops;
1607         return 0;
1608 }
1609
1610 static int kvm_vcpu_release(struct inode *inode, struct file *filp)
1611 {
1612         struct kvm_vcpu *vcpu = filp->private_data;
1613
1614         kvm_put_kvm(vcpu->kvm);
1615         return 0;
1616 }
1617
1618 static struct file_operations kvm_vcpu_fops = {
1619         .release        = kvm_vcpu_release,
1620         .unlocked_ioctl = kvm_vcpu_ioctl,
1621 #ifdef CONFIG_COMPAT
1622         .compat_ioctl   = kvm_vcpu_compat_ioctl,
1623 #endif
1624         .mmap           = kvm_vcpu_mmap,
1625         .llseek         = noop_llseek,
1626 };
1627
1628 /*
1629  * Allocates an inode for the vcpu.
1630  */
1631 static int create_vcpu_fd(struct kvm_vcpu *vcpu)
1632 {
1633         return anon_inode_getfd("kvm-vcpu", &kvm_vcpu_fops, vcpu, O_RDWR);
1634 }
1635
1636 /*
1637  * Creates some virtual cpus.  Good luck creating more than one.
1638  */
1639 static int kvm_vm_ioctl_create_vcpu(struct kvm *kvm, u32 id)
1640 {
1641         int r;
1642         struct kvm_vcpu *vcpu, *v;
1643
1644         vcpu = kvm_arch_vcpu_create(kvm, id);
1645         if (IS_ERR(vcpu))
1646                 return PTR_ERR(vcpu);
1647
1648         preempt_notifier_init(&vcpu->preempt_notifier, &kvm_preempt_ops);
1649
1650         r = kvm_arch_vcpu_setup(vcpu);
1651         if (r)
1652                 goto vcpu_destroy;
1653
1654         mutex_lock(&kvm->lock);
1655         if (!kvm_vcpu_compatible(vcpu)) {
1656                 r = -EINVAL;
1657                 goto unlock_vcpu_destroy;
1658         }
1659         if (atomic_read(&kvm->online_vcpus) == KVM_MAX_VCPUS) {
1660                 r = -EINVAL;
1661                 goto unlock_vcpu_destroy;
1662         }
1663
1664         kvm_for_each_vcpu(r, v, kvm)
1665                 if (v->vcpu_id == id) {
1666                         r = -EEXIST;
1667                         goto unlock_vcpu_destroy;
1668                 }
1669
1670         BUG_ON(kvm->vcpus[atomic_read(&kvm->online_vcpus)]);
1671
1672         /* Now it's all set up, let userspace reach it */
1673         kvm_get_kvm(kvm);
1674         r = create_vcpu_fd(vcpu);
1675         if (r < 0) {
1676                 kvm_put_kvm(kvm);
1677                 goto unlock_vcpu_destroy;
1678         }
1679
1680         kvm->vcpus[atomic_read(&kvm->online_vcpus)] = vcpu;
1681         smp_wmb();
1682         atomic_inc(&kvm->online_vcpus);
1683
1684         mutex_unlock(&kvm->lock);
1685         return r;
1686
1687 unlock_vcpu_destroy:
1688         mutex_unlock(&kvm->lock);
1689 vcpu_destroy:
1690         kvm_arch_vcpu_destroy(vcpu);
1691         return r;
1692 }
1693
1694 static int kvm_vcpu_ioctl_set_sigmask(struct kvm_vcpu *vcpu, sigset_t *sigset)
1695 {
1696         if (sigset) {
1697                 sigdelsetmask(sigset, sigmask(SIGKILL)|sigmask(SIGSTOP));
1698                 vcpu->sigset_active = 1;
1699                 vcpu->sigset = *sigset;
1700         } else
1701                 vcpu->sigset_active = 0;
1702         return 0;
1703 }
1704
1705 static long kvm_vcpu_ioctl(struct file *filp,
1706                            unsigned int ioctl, unsigned long arg)
1707 {
1708         struct kvm_vcpu *vcpu = filp->private_data;
1709         void __user *argp = (void __user *)arg;
1710         int r;
1711         struct kvm_fpu *fpu = NULL;
1712         struct kvm_sregs *kvm_sregs = NULL;
1713
1714         if (vcpu->kvm->mm != current->mm)
1715                 return -EIO;
1716
1717 #if defined(CONFIG_S390) || defined(CONFIG_PPC)
1718         /*
1719          * Special cases: vcpu ioctls that are asynchronous to vcpu execution,
1720          * so vcpu_load() would break it.
1721          */
1722         if (ioctl == KVM_S390_INTERRUPT || ioctl == KVM_INTERRUPT)
1723                 return kvm_arch_vcpu_ioctl(filp, ioctl, arg);
1724 #endif
1725
1726
1727         vcpu_load(vcpu);
1728         switch (ioctl) {
1729         case KVM_RUN:
1730                 r = -EINVAL;
1731                 if (arg)
1732                         goto out;
1733                 r = kvm_arch_vcpu_ioctl_run(vcpu, vcpu->run);
1734                 trace_kvm_userspace_exit(vcpu->run->exit_reason, r);
1735                 break;
1736         case KVM_GET_REGS: {
1737                 struct kvm_regs *kvm_regs;
1738
1739                 r = -ENOMEM;
1740                 kvm_regs = kzalloc(sizeof(struct kvm_regs), GFP_KERNEL);
1741                 if (!kvm_regs)
1742                         goto out;
1743                 r = kvm_arch_vcpu_ioctl_get_regs(vcpu, kvm_regs);
1744                 if (r)
1745                         goto out_free1;
1746                 r = -EFAULT;
1747                 if (copy_to_user(argp, kvm_regs, sizeof(struct kvm_regs)))
1748                         goto out_free1;
1749                 r = 0;
1750 out_free1:
1751                 kfree(kvm_regs);
1752                 break;
1753         }
1754         case KVM_SET_REGS: {
1755                 struct kvm_regs *kvm_regs;
1756
1757                 r = -ENOMEM;
1758                 kvm_regs = memdup_user(argp, sizeof(*kvm_regs));
1759                 if (IS_ERR(kvm_regs)) {
1760                         r = PTR_ERR(kvm_regs);
1761                         goto out;
1762                 }
1763                 r = kvm_arch_vcpu_ioctl_set_regs(vcpu, kvm_regs);
1764                 if (r)
1765                         goto out_free2;
1766                 r = 0;
1767 out_free2:
1768                 kfree(kvm_regs);
1769                 break;
1770         }
1771         case KVM_GET_SREGS: {
1772                 kvm_sregs = kzalloc(sizeof(struct kvm_sregs), GFP_KERNEL);
1773                 r = -ENOMEM;
1774                 if (!kvm_sregs)
1775                         goto out;
1776                 r = kvm_arch_vcpu_ioctl_get_sregs(vcpu, kvm_sregs);
1777                 if (r)
1778                         goto out;
1779                 r = -EFAULT;
1780                 if (copy_to_user(argp, kvm_sregs, sizeof(struct kvm_sregs)))
1781                         goto out;
1782                 r = 0;
1783                 break;
1784         }
1785         case KVM_SET_SREGS: {
1786                 kvm_sregs = memdup_user(argp, sizeof(*kvm_sregs));
1787                 if (IS_ERR(kvm_sregs)) {
1788                         r = PTR_ERR(kvm_sregs);
1789                         goto out;
1790                 }
1791                 r = kvm_arch_vcpu_ioctl_set_sregs(vcpu, kvm_sregs);
1792                 if (r)
1793                         goto out;
1794                 r = 0;
1795                 break;
1796         }
1797         case KVM_GET_MP_STATE: {
1798                 struct kvm_mp_state mp_state;
1799
1800                 r = kvm_arch_vcpu_ioctl_get_mpstate(vcpu, &mp_state);
1801                 if (r)
1802                         goto out;
1803                 r = -EFAULT;
1804                 if (copy_to_user(argp, &mp_state, sizeof mp_state))
1805                         goto out;
1806                 r = 0;
1807                 break;
1808         }
1809         case KVM_SET_MP_STATE: {
1810                 struct kvm_mp_state mp_state;
1811
1812                 r = -EFAULT;
1813                 if (copy_from_user(&mp_state, argp, sizeof mp_state))
1814                         goto out;
1815                 r = kvm_arch_vcpu_ioctl_set_mpstate(vcpu, &mp_state);
1816                 if (r)
1817                         goto out;
1818                 r = 0;
1819                 break;
1820         }
1821         case KVM_TRANSLATE: {
1822                 struct kvm_translation tr;
1823
1824                 r = -EFAULT;
1825                 if (copy_from_user(&tr, argp, sizeof tr))
1826                         goto out;
1827                 r = kvm_arch_vcpu_ioctl_translate(vcpu, &tr);
1828                 if (r)
1829                         goto out;
1830                 r = -EFAULT;
1831                 if (copy_to_user(argp, &tr, sizeof tr))
1832                         goto out;
1833                 r = 0;
1834                 break;
1835         }
1836         case KVM_SET_GUEST_DEBUG: {
1837                 struct kvm_guest_debug dbg;
1838
1839                 r = -EFAULT;
1840                 if (copy_from_user(&dbg, argp, sizeof dbg))
1841                         goto out;
1842                 r = kvm_arch_vcpu_ioctl_set_guest_debug(vcpu, &dbg);
1843                 if (r)
1844                         goto out;
1845                 r = 0;
1846                 break;
1847         }
1848         case KVM_SET_SIGNAL_MASK: {
1849                 struct kvm_signal_mask __user *sigmask_arg = argp;
1850                 struct kvm_signal_mask kvm_sigmask;
1851                 sigset_t sigset, *p;
1852
1853                 p = NULL;
1854                 if (argp) {
1855                         r = -EFAULT;
1856                         if (copy_from_user(&kvm_sigmask, argp,
1857                                            sizeof kvm_sigmask))
1858                                 goto out;
1859                         r = -EINVAL;
1860                         if (kvm_sigmask.len != sizeof sigset)
1861                                 goto out;
1862                         r = -EFAULT;
1863                         if (copy_from_user(&sigset, sigmask_arg->sigset,
1864                                            sizeof sigset))
1865                                 goto out;
1866                         p = &sigset;
1867                 }
1868                 r = kvm_vcpu_ioctl_set_sigmask(vcpu, p);
1869                 break;
1870         }
1871         case KVM_GET_FPU: {
1872                 fpu = kzalloc(sizeof(struct kvm_fpu), GFP_KERNEL);
1873                 r = -ENOMEM;
1874                 if (!fpu)
1875                         goto out;
1876                 r = kvm_arch_vcpu_ioctl_get_fpu(vcpu, fpu);
1877                 if (r)
1878                         goto out;
1879                 r = -EFAULT;
1880                 if (copy_to_user(argp, fpu, sizeof(struct kvm_fpu)))
1881                         goto out;
1882                 r = 0;
1883                 break;
1884         }
1885         case KVM_SET_FPU: {
1886                 fpu = memdup_user(argp, sizeof(*fpu));
1887                 if (IS_ERR(fpu)) {
1888                         r = PTR_ERR(fpu);
1889                         goto out;
1890                 }
1891                 r = kvm_arch_vcpu_ioctl_set_fpu(vcpu, fpu);
1892                 if (r)
1893                         goto out;
1894                 r = 0;
1895                 break;
1896         }
1897         default:
1898                 r = kvm_arch_vcpu_ioctl(filp, ioctl, arg);
1899         }
1900 out:
1901         vcpu_put(vcpu);
1902         kfree(fpu);
1903         kfree(kvm_sregs);
1904         return r;
1905 }
1906
1907 #ifdef CONFIG_COMPAT
1908 static long kvm_vcpu_compat_ioctl(struct file *filp,
1909                                   unsigned int ioctl, unsigned long arg)
1910 {
1911         struct kvm_vcpu *vcpu = filp->private_data;
1912         void __user *argp = compat_ptr(arg);
1913         int r;
1914
1915         if (vcpu->kvm->mm != current->mm)
1916                 return -EIO;
1917
1918         switch (ioctl) {
1919         case KVM_SET_SIGNAL_MASK: {
1920                 struct kvm_signal_mask __user *sigmask_arg = argp;
1921                 struct kvm_signal_mask kvm_sigmask;
1922                 compat_sigset_t csigset;
1923                 sigset_t sigset;
1924
1925                 if (argp) {
1926                         r = -EFAULT;
1927                         if (copy_from_user(&kvm_sigmask, argp,
1928                                            sizeof kvm_sigmask))
1929                                 goto out;
1930                         r = -EINVAL;
1931                         if (kvm_sigmask.len != sizeof csigset)
1932                                 goto out;
1933                         r = -EFAULT;
1934                         if (copy_from_user(&csigset, sigmask_arg->sigset,
1935                                            sizeof csigset))
1936                                 goto out;
1937                 }
1938                 sigset_from_compat(&sigset, &csigset);
1939                 r = kvm_vcpu_ioctl_set_sigmask(vcpu, &sigset);
1940                 break;
1941         }
1942         default:
1943                 r = kvm_vcpu_ioctl(filp, ioctl, arg);
1944         }
1945
1946 out:
1947         return r;
1948 }
1949 #endif
1950
1951 static long kvm_vm_ioctl(struct file *filp,
1952                            unsigned int ioctl, unsigned long arg)
1953 {
1954         struct kvm *kvm = filp->private_data;
1955         void __user *argp = (void __user *)arg;
1956         int r;
1957
1958         if (kvm->mm != current->mm)
1959                 return -EIO;
1960         switch (ioctl) {
1961         case KVM_CREATE_VCPU:
1962                 r = kvm_vm_ioctl_create_vcpu(kvm, arg);
1963                 if (r < 0)
1964                         goto out;
1965                 break;
1966         case KVM_SET_USER_MEMORY_REGION: {
1967                 struct kvm_userspace_memory_region kvm_userspace_mem;
1968
1969                 r = -EFAULT;
1970                 if (copy_from_user(&kvm_userspace_mem, argp,
1971                                                 sizeof kvm_userspace_mem))
1972                         goto out;
1973
1974                 r = kvm_vm_ioctl_set_memory_region(kvm, &kvm_userspace_mem, 1);
1975                 if (r)
1976                         goto out;
1977                 break;
1978         }
1979         case KVM_GET_DIRTY_LOG: {
1980                 struct kvm_dirty_log log;
1981
1982                 r = -EFAULT;
1983                 if (copy_from_user(&log, argp, sizeof log))
1984                         goto out;
1985                 r = kvm_vm_ioctl_get_dirty_log(kvm, &log);
1986                 if (r)
1987                         goto out;
1988                 break;
1989         }
1990 #ifdef KVM_COALESCED_MMIO_PAGE_OFFSET
1991         case KVM_REGISTER_COALESCED_MMIO: {
1992                 struct kvm_coalesced_mmio_zone zone;
1993                 r = -EFAULT;
1994                 if (copy_from_user(&zone, argp, sizeof zone))
1995                         goto out;
1996                 r = kvm_vm_ioctl_register_coalesced_mmio(kvm, &zone);
1997                 if (r)
1998                         goto out;
1999                 r = 0;
2000                 break;
2001         }
2002         case KVM_UNREGISTER_COALESCED_MMIO: {
2003                 struct kvm_coalesced_mmio_zone zone;
2004                 r = -EFAULT;
2005                 if (copy_from_user(&zone, argp, sizeof zone))
2006                         goto out;
2007                 r = kvm_vm_ioctl_unregister_coalesced_mmio(kvm, &zone);
2008                 if (r)
2009                         goto out;
2010                 r = 0;
2011                 break;
2012         }
2013 #endif
2014         case KVM_IRQFD: {
2015                 struct kvm_irqfd data;
2016
2017                 r = -EFAULT;
2018                 if (copy_from_user(&data, argp, sizeof data))
2019                         goto out;
2020                 r = kvm_irqfd(kvm, data.fd, data.gsi, data.flags);
2021                 break;
2022         }
2023         case KVM_IOEVENTFD: {
2024                 struct kvm_ioeventfd data;
2025
2026                 r = -EFAULT;
2027                 if (copy_from_user(&data, argp, sizeof data))
2028                         goto out;
2029                 r = kvm_ioeventfd(kvm, &data);
2030                 break;
2031         }
2032 #ifdef CONFIG_KVM_APIC_ARCHITECTURE
2033         case KVM_SET_BOOT_CPU_ID:
2034                 r = 0;
2035                 mutex_lock(&kvm->lock);
2036                 if (atomic_read(&kvm->online_vcpus) != 0)
2037                         r = -EBUSY;
2038                 else
2039                         kvm->bsp_vcpu_id = arg;
2040                 mutex_unlock(&kvm->lock);
2041                 break;
2042 #endif
2043         default:
2044                 r = kvm_arch_vm_ioctl(filp, ioctl, arg);
2045                 if (r == -ENOTTY)
2046                         r = kvm_vm_ioctl_assigned_device(kvm, ioctl, arg);
2047         }
2048 out:
2049         return r;
2050 }
2051
2052 #ifdef CONFIG_COMPAT
2053 struct compat_kvm_dirty_log {
2054         __u32 slot;
2055         __u32 padding1;
2056         union {
2057                 compat_uptr_t dirty_bitmap; /* one bit per page */
2058                 __u64 padding2;
2059         };
2060 };
2061
2062 static long kvm_vm_compat_ioctl(struct file *filp,
2063                            unsigned int ioctl, unsigned long arg)
2064 {
2065         struct kvm *kvm = filp->private_data;
2066         int r;
2067
2068         if (kvm->mm != current->mm)
2069                 return -EIO;
2070         switch (ioctl) {
2071         case KVM_GET_DIRTY_LOG: {
2072                 struct compat_kvm_dirty_log compat_log;
2073                 struct kvm_dirty_log log;
2074
2075                 r = -EFAULT;
2076                 if (copy_from_user(&compat_log, (void __user *)arg,
2077                                    sizeof(compat_log)))
2078                         goto out;
2079                 log.slot         = compat_log.slot;
2080                 log.padding1     = compat_log.padding1;
2081                 log.padding2     = compat_log.padding2;
2082                 log.dirty_bitmap = compat_ptr(compat_log.dirty_bitmap);
2083
2084                 r = kvm_vm_ioctl_get_dirty_log(kvm, &log);
2085                 if (r)
2086                         goto out;
2087                 break;
2088         }
2089         default:
2090                 r = kvm_vm_ioctl(filp, ioctl, arg);
2091         }
2092
2093 out:
2094         return r;
2095 }
2096 #endif
2097
2098 static int kvm_vm_fault(struct vm_area_struct *vma, struct vm_fault *vmf)
2099 {
2100         struct page *page[1];
2101         unsigned long addr;
2102         int npages;
2103         gfn_t gfn = vmf->pgoff;
2104         struct kvm *kvm = vma->vm_file->private_data;
2105
2106         addr = gfn_to_hva(kvm, gfn);
2107         if (kvm_is_error_hva(addr))
2108                 return VM_FAULT_SIGBUS;
2109
2110         npages = get_user_pages(current, current->mm, addr, 1, 1, 0, page,
2111                                 NULL);
2112         if (unlikely(npages != 1))
2113                 return VM_FAULT_SIGBUS;
2114
2115         vmf->page = page[0];
2116         return 0;
2117 }
2118
2119 static const struct vm_operations_struct kvm_vm_vm_ops = {
2120         .fault = kvm_vm_fault,
2121 };
2122
2123 static int kvm_vm_mmap(struct file *file, struct vm_area_struct *vma)
2124 {
2125         vma->vm_ops = &kvm_vm_vm_ops;
2126         return 0;
2127 }
2128
2129 static struct file_operations kvm_vm_fops = {
2130         .release        = kvm_vm_release,
2131         .unlocked_ioctl = kvm_vm_ioctl,
2132 #ifdef CONFIG_COMPAT
2133         .compat_ioctl   = kvm_vm_compat_ioctl,
2134 #endif
2135         .mmap           = kvm_vm_mmap,
2136         .llseek         = noop_llseek,
2137 };
2138
2139 static int kvm_dev_ioctl_create_vm(unsigned long type)
2140 {
2141         int r;
2142         struct kvm *kvm;
2143
2144         kvm = kvm_create_vm(type);
2145         if (IS_ERR(kvm))
2146                 return PTR_ERR(kvm);
2147 #ifdef KVM_COALESCED_MMIO_PAGE_OFFSET
2148         r = kvm_coalesced_mmio_init(kvm);
2149         if (r < 0) {
2150                 kvm_put_kvm(kvm);
2151                 return r;
2152         }
2153 #endif
2154         r = anon_inode_getfd("kvm-vm", &kvm_vm_fops, kvm, O_RDWR);
2155         if (r < 0)
2156                 kvm_put_kvm(kvm);
2157
2158         return r;
2159 }
2160
2161 static long kvm_dev_ioctl_check_extension_generic(long arg)
2162 {
2163         switch (arg) {
2164         case KVM_CAP_USER_MEMORY:
2165         case KVM_CAP_DESTROY_MEMORY_REGION_WORKS:
2166         case KVM_CAP_JOIN_MEMORY_REGIONS_WORKS:
2167 #ifdef CONFIG_KVM_APIC_ARCHITECTURE
2168         case KVM_CAP_SET_BOOT_CPU_ID:
2169 #endif
2170         case KVM_CAP_INTERNAL_ERROR_DATA:
2171                 return 1;
2172 #ifdef CONFIG_HAVE_KVM_IRQCHIP
2173         case KVM_CAP_IRQ_ROUTING:
2174                 return KVM_MAX_IRQ_ROUTES;
2175 #endif
2176         default:
2177                 break;
2178         }
2179         return kvm_dev_ioctl_check_extension(arg);
2180 }
2181
2182 static long kvm_dev_ioctl(struct file *filp,
2183                           unsigned int ioctl, unsigned long arg)
2184 {
2185         long r = -EINVAL;
2186
2187         switch (ioctl) {
2188         case KVM_GET_API_VERSION:
2189                 r = -EINVAL;
2190                 if (arg)
2191                         goto out;
2192                 r = KVM_API_VERSION;
2193                 break;
2194         case KVM_CREATE_VM:
2195                 r = kvm_dev_ioctl_create_vm(arg);
2196                 break;
2197         case KVM_CHECK_EXTENSION:
2198                 r = kvm_dev_ioctl_check_extension_generic(arg);
2199                 break;
2200         case KVM_GET_VCPU_MMAP_SIZE:
2201                 r = -EINVAL;
2202                 if (arg)
2203                         goto out;
2204                 r = PAGE_SIZE;     /* struct kvm_run */
2205 #ifdef CONFIG_X86
2206                 r += PAGE_SIZE;    /* pio data page */
2207 #endif
2208 #ifdef KVM_COALESCED_MMIO_PAGE_OFFSET
2209                 r += PAGE_SIZE;    /* coalesced mmio ring page */
2210 #endif
2211                 break;
2212         case KVM_TRACE_ENABLE:
2213         case KVM_TRACE_PAUSE:
2214         case KVM_TRACE_DISABLE:
2215                 r = -EOPNOTSUPP;
2216                 break;
2217         default:
2218                 return kvm_arch_dev_ioctl(filp, ioctl, arg);
2219         }
2220 out:
2221         return r;
2222 }
2223
2224 static struct file_operations kvm_chardev_ops = {
2225         .unlocked_ioctl = kvm_dev_ioctl,
2226         .compat_ioctl   = kvm_dev_ioctl,
2227         .llseek         = noop_llseek,
2228 };
2229
2230 static struct miscdevice kvm_dev = {
2231         KVM_MINOR,
2232         "kvm",
2233         &kvm_chardev_ops,
2234 };
2235
2236 static void hardware_enable_nolock(void *junk)
2237 {
2238         int cpu = raw_smp_processor_id();
2239         int r;
2240
2241         if (cpumask_test_cpu(cpu, cpus_hardware_enabled))
2242                 return;
2243
2244         cpumask_set_cpu(cpu, cpus_hardware_enabled);
2245
2246         r = kvm_arch_hardware_enable(NULL);
2247
2248         if (r) {
2249                 cpumask_clear_cpu(cpu, cpus_hardware_enabled);
2250                 atomic_inc(&hardware_enable_failed);
2251                 printk(KERN_INFO "kvm: enabling virtualization on "
2252                                  "CPU%d failed\n", cpu);
2253         }
2254 }
2255
2256 static void hardware_enable(void *junk)
2257 {
2258         raw_spin_lock(&kvm_lock);
2259         hardware_enable_nolock(junk);
2260         raw_spin_unlock(&kvm_lock);
2261 }
2262
2263 static void hardware_disable_nolock(void *junk)
2264 {
2265         int cpu = raw_smp_processor_id();
2266
2267         if (!cpumask_test_cpu(cpu, cpus_hardware_enabled))
2268                 return;
2269         cpumask_clear_cpu(cpu, cpus_hardware_enabled);
2270         kvm_arch_hardware_disable(NULL);
2271 }
2272
2273 static void hardware_disable(void *junk)
2274 {
2275         raw_spin_lock(&kvm_lock);
2276         hardware_disable_nolock(junk);
2277         raw_spin_unlock(&kvm_lock);
2278 }
2279
2280 static void hardware_disable_all_nolock(void)
2281 {
2282         BUG_ON(!kvm_usage_count);
2283
2284         kvm_usage_count--;
2285         if (!kvm_usage_count)
2286                 on_each_cpu(hardware_disable_nolock, NULL, 1);
2287 }
2288
2289 static void hardware_disable_all(void)
2290 {
2291         raw_spin_lock(&kvm_lock);
2292         hardware_disable_all_nolock();
2293         raw_spin_unlock(&kvm_lock);
2294 }
2295
2296 static int hardware_enable_all(void)
2297 {
2298         int r = 0;
2299
2300         raw_spin_lock(&kvm_lock);
2301
2302         kvm_usage_count++;
2303         if (kvm_usage_count == 1) {
2304                 atomic_set(&hardware_enable_failed, 0);
2305                 on_each_cpu(hardware_enable_nolock, NULL, 1);
2306
2307                 if (atomic_read(&hardware_enable_failed)) {
2308                         hardware_disable_all_nolock();
2309                         r = -EBUSY;
2310                 }
2311         }
2312
2313         raw_spin_unlock(&kvm_lock);
2314
2315         return r;
2316 }
2317
2318 static int kvm_cpu_hotplug(struct notifier_block *notifier, unsigned long val,
2319                            void *v)
2320 {
2321         int cpu = (long)v;
2322
2323         if (!kvm_usage_count)
2324                 return NOTIFY_OK;
2325
2326         val &= ~CPU_TASKS_FROZEN;
2327         switch (val) {
2328         case CPU_DYING:
2329                 printk(KERN_INFO "kvm: disabling virtualization on CPU%d\n",
2330                        cpu);
2331                 hardware_disable(NULL);
2332                 break;
2333         case CPU_STARTING:
2334                 printk(KERN_INFO "kvm: enabling virtualization on CPU%d\n",
2335                        cpu);
2336                 hardware_enable(NULL);
2337                 break;
2338         }
2339         return NOTIFY_OK;
2340 }
2341
2342
2343 asmlinkage void kvm_spurious_fault(void)
2344 {
2345         /* Fault while not rebooting.  We want the trace. */
2346         BUG();
2347 }
2348 EXPORT_SYMBOL_GPL(kvm_spurious_fault);
2349
2350 static int kvm_reboot(struct notifier_block *notifier, unsigned long val,
2351                       void *v)
2352 {
2353         /*
2354          * Some (well, at least mine) BIOSes hang on reboot if
2355          * in vmx root mode.
2356          *
2357          * And Intel TXT required VMX off for all cpu when system shutdown.
2358          */
2359         printk(KERN_INFO "kvm: exiting hardware virtualization\n");
2360         kvm_rebooting = true;
2361         on_each_cpu(hardware_disable_nolock, NULL, 1);
2362         return NOTIFY_OK;
2363 }
2364
2365 static struct notifier_block kvm_reboot_notifier = {
2366         .notifier_call = kvm_reboot,
2367         .priority = 0,
2368 };
2369
2370 static void kvm_io_bus_destroy(struct kvm_io_bus *bus)
2371 {
2372         int i;
2373
2374         for (i = 0; i < bus->dev_count; i++) {
2375                 struct kvm_io_device *pos = bus->range[i].dev;
2376
2377                 kvm_iodevice_destructor(pos);
2378         }
2379         kfree(bus);
2380 }
2381
2382 int kvm_io_bus_sort_cmp(const void *p1, const void *p2)
2383 {
2384         const struct kvm_io_range *r1 = p1;
2385         const struct kvm_io_range *r2 = p2;
2386
2387         if (r1->addr < r2->addr)
2388                 return -1;
2389         if (r1->addr + r1->len > r2->addr + r2->len)
2390                 return 1;
2391         return 0;
2392 }
2393
2394 int kvm_io_bus_insert_dev(struct kvm_io_bus *bus, struct kvm_io_device *dev,
2395                           gpa_t addr, int len)
2396 {
2397         if (bus->dev_count == NR_IOBUS_DEVS)
2398                 return -ENOSPC;
2399
2400         bus->range[bus->dev_count++] = (struct kvm_io_range) {
2401                 .addr = addr,
2402                 .len = len,
2403                 .dev = dev,
2404         };
2405
2406         sort(bus->range, bus->dev_count, sizeof(struct kvm_io_range),
2407                 kvm_io_bus_sort_cmp, NULL);
2408
2409         return 0;
2410 }
2411
2412 int kvm_io_bus_get_first_dev(struct kvm_io_bus *bus,
2413                              gpa_t addr, int len)
2414 {
2415         struct kvm_io_range *range, key;
2416         int off;
2417
2418         key = (struct kvm_io_range) {
2419                 .addr = addr,
2420                 .len = len,
2421         };
2422
2423         range = bsearch(&key, bus->range, bus->dev_count,
2424                         sizeof(struct kvm_io_range), kvm_io_bus_sort_cmp);
2425         if (range == NULL)
2426                 return -ENOENT;
2427
2428         off = range - bus->range;
2429
2430         while (off > 0 && kvm_io_bus_sort_cmp(&key, &bus->range[off-1]) == 0)
2431                 off--;
2432
2433         return off;
2434 }
2435
2436 /* kvm_io_bus_write - called under kvm->slots_lock */
2437 int kvm_io_bus_write(struct kvm *kvm, enum kvm_bus bus_idx, gpa_t addr,
2438                      int len, const void *val)
2439 {
2440         int idx;
2441         struct kvm_io_bus *bus;
2442         struct kvm_io_range range;
2443
2444         range = (struct kvm_io_range) {
2445                 .addr = addr,
2446                 .len = len,
2447         };
2448
2449         bus = srcu_dereference(kvm->buses[bus_idx], &kvm->srcu);
2450         idx = kvm_io_bus_get_first_dev(bus, addr, len);
2451         if (idx < 0)
2452                 return -EOPNOTSUPP;
2453
2454         while (idx < bus->dev_count &&
2455                 kvm_io_bus_sort_cmp(&range, &bus->range[idx]) == 0) {
2456                 if (!kvm_iodevice_write(bus->range[idx].dev, addr, len, val))
2457                         return 0;
2458                 idx++;
2459         }
2460
2461         return -EOPNOTSUPP;
2462 }
2463
2464 /* kvm_io_bus_read - called under kvm->slots_lock */
2465 int kvm_io_bus_read(struct kvm *kvm, enum kvm_bus bus_idx, gpa_t addr,
2466                     int len, void *val)
2467 {
2468         int idx;
2469         struct kvm_io_bus *bus;
2470         struct kvm_io_range range;
2471
2472         range = (struct kvm_io_range) {
2473                 .addr = addr,
2474                 .len = len,
2475         };
2476
2477         bus = srcu_dereference(kvm->buses[bus_idx], &kvm->srcu);
2478         idx = kvm_io_bus_get_first_dev(bus, addr, len);
2479         if (idx < 0)
2480                 return -EOPNOTSUPP;
2481
2482         while (idx < bus->dev_count &&
2483                 kvm_io_bus_sort_cmp(&range, &bus->range[idx]) == 0) {
2484                 if (!kvm_iodevice_read(bus->range[idx].dev, addr, len, val))
2485                         return 0;
2486                 idx++;
2487         }
2488
2489         return -EOPNOTSUPP;
2490 }
2491
2492 /* Caller must hold slots_lock. */
2493 int kvm_io_bus_register_dev(struct kvm *kvm, enum kvm_bus bus_idx, gpa_t addr,
2494                             int len, struct kvm_io_device *dev)
2495 {
2496         struct kvm_io_bus *new_bus, *bus;
2497
2498         bus = kvm->buses[bus_idx];
2499         if (bus->dev_count > NR_IOBUS_DEVS-1)
2500                 return -ENOSPC;
2501
2502         new_bus = kmemdup(bus, sizeof(struct kvm_io_bus), GFP_KERNEL);
2503         if (!new_bus)
2504                 return -ENOMEM;
2505         kvm_io_bus_insert_dev(new_bus, dev, addr, len);
2506         rcu_assign_pointer(kvm->buses[bus_idx], new_bus);
2507         synchronize_srcu_expedited(&kvm->srcu);
2508         kfree(bus);
2509
2510         return 0;
2511 }
2512
2513 /* Caller must hold slots_lock. */
2514 int kvm_io_bus_unregister_dev(struct kvm *kvm, enum kvm_bus bus_idx,
2515                               struct kvm_io_device *dev)
2516 {
2517         int i, r;
2518         struct kvm_io_bus *new_bus, *bus;
2519
2520         bus = kvm->buses[bus_idx];
2521
2522         new_bus = kmemdup(bus, sizeof(*bus), GFP_KERNEL);
2523         if (!new_bus)
2524                 return -ENOMEM;
2525
2526         r = -ENOENT;
2527         for (i = 0; i < new_bus->dev_count; i++)
2528                 if (new_bus->range[i].dev == dev) {
2529                         r = 0;
2530                         new_bus->dev_count--;
2531                         new_bus->range[i] = new_bus->range[new_bus->dev_count];
2532                         sort(new_bus->range, new_bus->dev_count,
2533                              sizeof(struct kvm_io_range),
2534                              kvm_io_bus_sort_cmp, NULL);
2535                         break;
2536                 }
2537
2538         if (r) {
2539                 kfree(new_bus);
2540                 return r;
2541         }
2542
2543         rcu_assign_pointer(kvm->buses[bus_idx], new_bus);
2544         synchronize_srcu_expedited(&kvm->srcu);
2545         kfree(bus);
2546         return r;
2547 }
2548
2549 static struct notifier_block kvm_cpu_notifier = {
2550         .notifier_call = kvm_cpu_hotplug,
2551 };
2552
2553 static int vm_stat_get(void *_offset, u64 *val)
2554 {
2555         unsigned offset = (long)_offset;
2556         struct kvm *kvm;
2557
2558         *val = 0;
2559         raw_spin_lock(&kvm_lock);
2560         list_for_each_entry(kvm, &vm_list, vm_list)
2561                 *val += *(u32 *)((void *)kvm + offset);
2562         raw_spin_unlock(&kvm_lock);
2563         return 0;
2564 }
2565
2566 DEFINE_SIMPLE_ATTRIBUTE(vm_stat_fops, vm_stat_get, NULL, "%llu\n");
2567
2568 static int vcpu_stat_get(void *_offset, u64 *val)
2569 {
2570         unsigned offset = (long)_offset;
2571         struct kvm *kvm;
2572         struct kvm_vcpu *vcpu;
2573         int i;
2574
2575         *val = 0;
2576         raw_spin_lock(&kvm_lock);
2577         list_for_each_entry(kvm, &vm_list, vm_list)
2578                 kvm_for_each_vcpu(i, vcpu, kvm)
2579                         *val += *(u32 *)((void *)vcpu + offset);
2580
2581         raw_spin_unlock(&kvm_lock);
2582         return 0;
2583 }
2584
2585 DEFINE_SIMPLE_ATTRIBUTE(vcpu_stat_fops, vcpu_stat_get, NULL, "%llu\n");
2586
2587 static const struct file_operations *stat_fops[] = {
2588         [KVM_STAT_VCPU] = &vcpu_stat_fops,
2589         [KVM_STAT_VM]   = &vm_stat_fops,
2590 };
2591
2592 static int kvm_init_debug(void)
2593 {
2594         int r = -EFAULT;
2595         struct kvm_stats_debugfs_item *p;
2596
2597         kvm_debugfs_dir = debugfs_create_dir("kvm", NULL);
2598         if (kvm_debugfs_dir == NULL)
2599                 goto out;
2600
2601         for (p = debugfs_entries; p->name; ++p) {
2602                 p->dentry = debugfs_create_file(p->name, 0444, kvm_debugfs_dir,
2603                                                 (void *)(long)p->offset,
2604                                                 stat_fops[p->kind]);
2605                 if (p->dentry == NULL)
2606                         goto out_dir;
2607         }
2608
2609         return 0;
2610
2611 out_dir:
2612         debugfs_remove_recursive(kvm_debugfs_dir);
2613 out:
2614         return r;
2615 }
2616
2617 static void kvm_exit_debug(void)
2618 {
2619         struct kvm_stats_debugfs_item *p;
2620
2621         for (p = debugfs_entries; p->name; ++p)
2622                 debugfs_remove(p->dentry);
2623         debugfs_remove(kvm_debugfs_dir);
2624 }
2625
2626 static int kvm_suspend(void)
2627 {
2628         if (kvm_usage_count)
2629                 hardware_disable_nolock(NULL);
2630         return 0;
2631 }
2632
2633 static void kvm_resume(void)
2634 {
2635         if (kvm_usage_count) {
2636                 WARN_ON(raw_spin_is_locked(&kvm_lock));
2637                 hardware_enable_nolock(NULL);
2638         }
2639 }
2640
2641 static struct syscore_ops kvm_syscore_ops = {
2642         .suspend = kvm_suspend,
2643         .resume = kvm_resume,
2644 };
2645
2646 struct page *bad_page;
2647 pfn_t bad_pfn;
2648
2649 static inline
2650 struct kvm_vcpu *preempt_notifier_to_vcpu(struct preempt_notifier *pn)
2651 {
2652         return container_of(pn, struct kvm_vcpu, preempt_notifier);
2653 }
2654
2655 static void kvm_sched_in(struct preempt_notifier *pn, int cpu)
2656 {
2657         struct kvm_vcpu *vcpu = preempt_notifier_to_vcpu(pn);
2658
2659         kvm_arch_vcpu_load(vcpu, cpu);
2660 }
2661
2662 static void kvm_sched_out(struct preempt_notifier *pn,
2663                           struct task_struct *next)
2664 {
2665         struct kvm_vcpu *vcpu = preempt_notifier_to_vcpu(pn);
2666
2667         kvm_arch_vcpu_put(vcpu);
2668 }
2669
2670 int kvm_init(void *opaque, unsigned vcpu_size, unsigned vcpu_align,
2671                   struct module *module)
2672 {
2673         int r;
2674         int cpu;
2675
2676         r = kvm_arch_init(opaque);
2677         if (r)
2678                 goto out_fail;
2679
2680         bad_page = alloc_page(GFP_KERNEL | __GFP_ZERO);
2681
2682         if (bad_page == NULL) {
2683                 r = -ENOMEM;
2684                 goto out;
2685         }
2686
2687         bad_pfn = page_to_pfn(bad_page);
2688
2689         hwpoison_page = alloc_page(GFP_KERNEL | __GFP_ZERO);
2690
2691         if (hwpoison_page == NULL) {
2692                 r = -ENOMEM;
2693                 goto out_free_0;
2694         }
2695
2696         hwpoison_pfn = page_to_pfn(hwpoison_page);
2697
2698         fault_page = alloc_page(GFP_KERNEL | __GFP_ZERO);
2699
2700         if (fault_page == NULL) {
2701                 r = -ENOMEM;
2702                 goto out_free_0;
2703         }
2704
2705         fault_pfn = page_to_pfn(fault_page);
2706
2707         if (!zalloc_cpumask_var(&cpus_hardware_enabled, GFP_KERNEL)) {
2708                 r = -ENOMEM;
2709                 goto out_free_0;
2710         }
2711
2712         r = kvm_arch_hardware_setup();
2713         if (r < 0)
2714                 goto out_free_0a;
2715
2716         for_each_online_cpu(cpu) {
2717                 smp_call_function_single(cpu,
2718                                 kvm_arch_check_processor_compat,
2719                                 &r, 1);
2720                 if (r < 0)
2721                         goto out_free_1;
2722         }
2723
2724         r = register_cpu_notifier(&kvm_cpu_notifier);
2725         if (r)
2726                 goto out_free_2;
2727         register_reboot_notifier(&kvm_reboot_notifier);
2728
2729         /* A kmem cache lets us meet the alignment requirements of fx_save. */
2730         if (!vcpu_align)
2731                 vcpu_align = __alignof__(struct kvm_vcpu);
2732         kvm_vcpu_cache = kmem_cache_create("kvm_vcpu", vcpu_size, vcpu_align,
2733                                            0, NULL);
2734         if (!kvm_vcpu_cache) {
2735                 r = -ENOMEM;
2736                 goto out_free_3;
2737         }
2738
2739         r = kvm_async_pf_init();
2740         if (r)
2741                 goto out_free;
2742
2743         kvm_chardev_ops.owner = module;
2744         kvm_vm_fops.owner = module;
2745         kvm_vcpu_fops.owner = module;
2746
2747         r = misc_register(&kvm_dev);
2748         if (r) {
2749                 printk(KERN_ERR "kvm: misc device register failed\n");
2750                 goto out_unreg;
2751         }
2752
2753         register_syscore_ops(&kvm_syscore_ops);
2754
2755         kvm_preempt_ops.sched_in = kvm_sched_in;
2756         kvm_preempt_ops.sched_out = kvm_sched_out;
2757
2758         r = kvm_init_debug();
2759         if (r) {
2760                 printk(KERN_ERR "kvm: create debugfs files failed\n");
2761                 goto out_undebugfs;
2762         }
2763
2764         return 0;
2765
2766 out_undebugfs:
2767         unregister_syscore_ops(&kvm_syscore_ops);
2768 out_unreg:
2769         kvm_async_pf_deinit();
2770 out_free:
2771         kmem_cache_destroy(kvm_vcpu_cache);
2772 out_free_3:
2773         unregister_reboot_notifier(&kvm_reboot_notifier);
2774         unregister_cpu_notifier(&kvm_cpu_notifier);
2775 out_free_2:
2776 out_free_1:
2777         kvm_arch_hardware_unsetup();
2778 out_free_0a:
2779         free_cpumask_var(cpus_hardware_enabled);
2780 out_free_0:
2781         if (fault_page)
2782                 __free_page(fault_page);
2783         if (hwpoison_page)
2784                 __free_page(hwpoison_page);
2785         __free_page(bad_page);
2786 out:
2787         kvm_arch_exit();
2788 out_fail:
2789         return r;
2790 }
2791 EXPORT_SYMBOL_GPL(kvm_init);
2792
2793 void kvm_exit(void)
2794 {
2795         kvm_exit_debug();
2796         misc_deregister(&kvm_dev);
2797         kmem_cache_destroy(kvm_vcpu_cache);
2798         kvm_async_pf_deinit();
2799         unregister_syscore_ops(&kvm_syscore_ops);
2800         unregister_reboot_notifier(&kvm_reboot_notifier);
2801         unregister_cpu_notifier(&kvm_cpu_notifier);
2802         on_each_cpu(hardware_disable_nolock, NULL, 1);
2803         kvm_arch_hardware_unsetup();
2804         kvm_arch_exit();
2805         free_cpumask_var(cpus_hardware_enabled);
2806         __free_page(hwpoison_page);
2807         __free_page(bad_page);
2808 }
2809 EXPORT_SYMBOL_GPL(kvm_exit);