KVM: introduce wrapper functions for creating/destroying dirty bitmaps
[linux-2.6.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/sysdev.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
51 #include <asm/processor.h>
52 #include <asm/io.h>
53 #include <asm/uaccess.h>
54 #include <asm/pgtable.h>
55 #include <asm-generic/bitops/le.h>
56
57 #include "coalesced_mmio.h"
58 #include "async_pf.h"
59
60 #define CREATE_TRACE_POINTS
61 #include <trace/events/kvm.h>
62
63 MODULE_AUTHOR("Qumranet");
64 MODULE_LICENSE("GPL");
65
66 /*
67  * Ordering of locks:
68  *
69  *              kvm->lock --> kvm->slots_lock --> kvm->irq_lock
70  */
71
72 DEFINE_SPINLOCK(kvm_lock);
73 LIST_HEAD(vm_list);
74
75 static cpumask_var_t cpus_hardware_enabled;
76 static int kvm_usage_count = 0;
77 static atomic_t hardware_enable_failed;
78
79 struct kmem_cache *kvm_vcpu_cache;
80 EXPORT_SYMBOL_GPL(kvm_vcpu_cache);
81
82 static __read_mostly struct preempt_ops kvm_preempt_ops;
83
84 struct dentry *kvm_debugfs_dir;
85
86 static long kvm_vcpu_ioctl(struct file *file, unsigned int ioctl,
87                            unsigned long arg);
88 static int hardware_enable_all(void);
89 static void hardware_disable_all(void);
90
91 static void kvm_io_bus_destroy(struct kvm_io_bus *bus);
92
93 static bool kvm_rebooting;
94
95 static bool largepages_enabled = true;
96
97 static struct page *hwpoison_page;
98 static pfn_t hwpoison_pfn;
99
100 static struct page *fault_page;
101 static pfn_t fault_pfn;
102
103 inline int kvm_is_mmio_pfn(pfn_t pfn)
104 {
105         if (pfn_valid(pfn)) {
106                 struct page *page = compound_head(pfn_to_page(pfn));
107                 return PageReserved(page);
108         }
109
110         return true;
111 }
112
113 /*
114  * Switches to specified vcpu, until a matching vcpu_put()
115  */
116 void vcpu_load(struct kvm_vcpu *vcpu)
117 {
118         int cpu;
119
120         mutex_lock(&vcpu->mutex);
121         cpu = get_cpu();
122         preempt_notifier_register(&vcpu->preempt_notifier);
123         kvm_arch_vcpu_load(vcpu, cpu);
124         put_cpu();
125 }
126
127 void vcpu_put(struct kvm_vcpu *vcpu)
128 {
129         preempt_disable();
130         kvm_arch_vcpu_put(vcpu);
131         preempt_notifier_unregister(&vcpu->preempt_notifier);
132         preempt_enable();
133         mutex_unlock(&vcpu->mutex);
134 }
135
136 static void ack_flush(void *_completed)
137 {
138 }
139
140 static bool make_all_cpus_request(struct kvm *kvm, unsigned int req)
141 {
142         int i, cpu, me;
143         cpumask_var_t cpus;
144         bool called = true;
145         struct kvm_vcpu *vcpu;
146
147         zalloc_cpumask_var(&cpus, GFP_ATOMIC);
148
149         raw_spin_lock(&kvm->requests_lock);
150         me = smp_processor_id();
151         kvm_for_each_vcpu(i, vcpu, kvm) {
152                 if (kvm_make_check_request(req, vcpu))
153                         continue;
154                 cpu = vcpu->cpu;
155                 if (cpus != NULL && cpu != -1 && cpu != me)
156                         cpumask_set_cpu(cpu, cpus);
157         }
158         if (unlikely(cpus == NULL))
159                 smp_call_function_many(cpu_online_mask, ack_flush, NULL, 1);
160         else if (!cpumask_empty(cpus))
161                 smp_call_function_many(cpus, ack_flush, NULL, 1);
162         else
163                 called = false;
164         raw_spin_unlock(&kvm->requests_lock);
165         free_cpumask_var(cpus);
166         return called;
167 }
168
169 void kvm_flush_remote_tlbs(struct kvm *kvm)
170 {
171         if (make_all_cpus_request(kvm, KVM_REQ_TLB_FLUSH))
172                 ++kvm->stat.remote_tlb_flush;
173 }
174
175 void kvm_reload_remote_mmus(struct kvm *kvm)
176 {
177         make_all_cpus_request(kvm, KVM_REQ_MMU_RELOAD);
178 }
179
180 int kvm_vcpu_init(struct kvm_vcpu *vcpu, struct kvm *kvm, unsigned id)
181 {
182         struct page *page;
183         int r;
184
185         mutex_init(&vcpu->mutex);
186         vcpu->cpu = -1;
187         vcpu->kvm = kvm;
188         vcpu->vcpu_id = id;
189         init_waitqueue_head(&vcpu->wq);
190         kvm_async_pf_vcpu_init(vcpu);
191
192         page = alloc_page(GFP_KERNEL | __GFP_ZERO);
193         if (!page) {
194                 r = -ENOMEM;
195                 goto fail;
196         }
197         vcpu->run = page_address(page);
198
199         r = kvm_arch_vcpu_init(vcpu);
200         if (r < 0)
201                 goto fail_free_run;
202         return 0;
203
204 fail_free_run:
205         free_page((unsigned long)vcpu->run);
206 fail:
207         return r;
208 }
209 EXPORT_SYMBOL_GPL(kvm_vcpu_init);
210
211 void kvm_vcpu_uninit(struct kvm_vcpu *vcpu)
212 {
213         kvm_arch_vcpu_uninit(vcpu);
214         free_page((unsigned long)vcpu->run);
215 }
216 EXPORT_SYMBOL_GPL(kvm_vcpu_uninit);
217
218 #if defined(CONFIG_MMU_NOTIFIER) && defined(KVM_ARCH_WANT_MMU_NOTIFIER)
219 static inline struct kvm *mmu_notifier_to_kvm(struct mmu_notifier *mn)
220 {
221         return container_of(mn, struct kvm, mmu_notifier);
222 }
223
224 static void kvm_mmu_notifier_invalidate_page(struct mmu_notifier *mn,
225                                              struct mm_struct *mm,
226                                              unsigned long address)
227 {
228         struct kvm *kvm = mmu_notifier_to_kvm(mn);
229         int need_tlb_flush, idx;
230
231         /*
232          * When ->invalidate_page runs, the linux pte has been zapped
233          * already but the page is still allocated until
234          * ->invalidate_page returns. So if we increase the sequence
235          * here the kvm page fault will notice if the spte can't be
236          * established because the page is going to be freed. If
237          * instead the kvm page fault establishes the spte before
238          * ->invalidate_page runs, kvm_unmap_hva will release it
239          * before returning.
240          *
241          * The sequence increase only need to be seen at spin_unlock
242          * time, and not at spin_lock time.
243          *
244          * Increasing the sequence after the spin_unlock would be
245          * unsafe because the kvm page fault could then establish the
246          * pte after kvm_unmap_hva returned, without noticing the page
247          * is going to be freed.
248          */
249         idx = srcu_read_lock(&kvm->srcu);
250         spin_lock(&kvm->mmu_lock);
251         kvm->mmu_notifier_seq++;
252         need_tlb_flush = kvm_unmap_hva(kvm, address);
253         spin_unlock(&kvm->mmu_lock);
254         srcu_read_unlock(&kvm->srcu, idx);
255
256         /* we've to flush the tlb before the pages can be freed */
257         if (need_tlb_flush)
258                 kvm_flush_remote_tlbs(kvm);
259
260 }
261
262 static void kvm_mmu_notifier_change_pte(struct mmu_notifier *mn,
263                                         struct mm_struct *mm,
264                                         unsigned long address,
265                                         pte_t pte)
266 {
267         struct kvm *kvm = mmu_notifier_to_kvm(mn);
268         int idx;
269
270         idx = srcu_read_lock(&kvm->srcu);
271         spin_lock(&kvm->mmu_lock);
272         kvm->mmu_notifier_seq++;
273         kvm_set_spte_hva(kvm, address, pte);
274         spin_unlock(&kvm->mmu_lock);
275         srcu_read_unlock(&kvm->srcu, idx);
276 }
277
278 static void kvm_mmu_notifier_invalidate_range_start(struct mmu_notifier *mn,
279                                                     struct mm_struct *mm,
280                                                     unsigned long start,
281                                                     unsigned long end)
282 {
283         struct kvm *kvm = mmu_notifier_to_kvm(mn);
284         int need_tlb_flush = 0, idx;
285
286         idx = srcu_read_lock(&kvm->srcu);
287         spin_lock(&kvm->mmu_lock);
288         /*
289          * The count increase must become visible at unlock time as no
290          * spte can be established without taking the mmu_lock and
291          * count is also read inside the mmu_lock critical section.
292          */
293         kvm->mmu_notifier_count++;
294         for (; start < end; start += PAGE_SIZE)
295                 need_tlb_flush |= kvm_unmap_hva(kvm, start);
296         spin_unlock(&kvm->mmu_lock);
297         srcu_read_unlock(&kvm->srcu, idx);
298
299         /* we've to flush the tlb before the pages can be freed */
300         if (need_tlb_flush)
301                 kvm_flush_remote_tlbs(kvm);
302 }
303
304 static void kvm_mmu_notifier_invalidate_range_end(struct mmu_notifier *mn,
305                                                   struct mm_struct *mm,
306                                                   unsigned long start,
307                                                   unsigned long end)
308 {
309         struct kvm *kvm = mmu_notifier_to_kvm(mn);
310
311         spin_lock(&kvm->mmu_lock);
312         /*
313          * This sequence increase will notify the kvm page fault that
314          * the page that is going to be mapped in the spte could have
315          * been freed.
316          */
317         kvm->mmu_notifier_seq++;
318         /*
319          * The above sequence increase must be visible before the
320          * below count decrease but both values are read by the kvm
321          * page fault under mmu_lock spinlock so we don't need to add
322          * a smb_wmb() here in between the two.
323          */
324         kvm->mmu_notifier_count--;
325         spin_unlock(&kvm->mmu_lock);
326
327         BUG_ON(kvm->mmu_notifier_count < 0);
328 }
329
330 static int kvm_mmu_notifier_clear_flush_young(struct mmu_notifier *mn,
331                                               struct mm_struct *mm,
332                                               unsigned long address)
333 {
334         struct kvm *kvm = mmu_notifier_to_kvm(mn);
335         int young, idx;
336
337         idx = srcu_read_lock(&kvm->srcu);
338         spin_lock(&kvm->mmu_lock);
339         young = kvm_age_hva(kvm, address);
340         spin_unlock(&kvm->mmu_lock);
341         srcu_read_unlock(&kvm->srcu, idx);
342
343         if (young)
344                 kvm_flush_remote_tlbs(kvm);
345
346         return young;
347 }
348
349 static void kvm_mmu_notifier_release(struct mmu_notifier *mn,
350                                      struct mm_struct *mm)
351 {
352         struct kvm *kvm = mmu_notifier_to_kvm(mn);
353         int idx;
354
355         idx = srcu_read_lock(&kvm->srcu);
356         kvm_arch_flush_shadow(kvm);
357         srcu_read_unlock(&kvm->srcu, idx);
358 }
359
360 static const struct mmu_notifier_ops kvm_mmu_notifier_ops = {
361         .invalidate_page        = kvm_mmu_notifier_invalidate_page,
362         .invalidate_range_start = kvm_mmu_notifier_invalidate_range_start,
363         .invalidate_range_end   = kvm_mmu_notifier_invalidate_range_end,
364         .clear_flush_young      = kvm_mmu_notifier_clear_flush_young,
365         .change_pte             = kvm_mmu_notifier_change_pte,
366         .release                = kvm_mmu_notifier_release,
367 };
368
369 static int kvm_init_mmu_notifier(struct kvm *kvm)
370 {
371         kvm->mmu_notifier.ops = &kvm_mmu_notifier_ops;
372         return mmu_notifier_register(&kvm->mmu_notifier, current->mm);
373 }
374
375 #else  /* !(CONFIG_MMU_NOTIFIER && KVM_ARCH_WANT_MMU_NOTIFIER) */
376
377 static int kvm_init_mmu_notifier(struct kvm *kvm)
378 {
379         return 0;
380 }
381
382 #endif /* CONFIG_MMU_NOTIFIER && KVM_ARCH_WANT_MMU_NOTIFIER */
383
384 static struct kvm *kvm_create_vm(void)
385 {
386         int r = 0, i;
387         struct kvm *kvm = kvm_arch_create_vm();
388
389         if (IS_ERR(kvm))
390                 goto out;
391
392         r = hardware_enable_all();
393         if (r)
394                 goto out_err_nodisable;
395
396 #ifdef CONFIG_HAVE_KVM_IRQCHIP
397         INIT_HLIST_HEAD(&kvm->mask_notifier_list);
398         INIT_HLIST_HEAD(&kvm->irq_ack_notifier_list);
399 #endif
400
401         r = -ENOMEM;
402         kvm->memslots = kzalloc(sizeof(struct kvm_memslots), GFP_KERNEL);
403         if (!kvm->memslots)
404                 goto out_err;
405         if (init_srcu_struct(&kvm->srcu))
406                 goto out_err;
407         for (i = 0; i < KVM_NR_BUSES; i++) {
408                 kvm->buses[i] = kzalloc(sizeof(struct kvm_io_bus),
409                                         GFP_KERNEL);
410                 if (!kvm->buses[i]) {
411                         cleanup_srcu_struct(&kvm->srcu);
412                         goto out_err;
413                 }
414         }
415
416         r = kvm_init_mmu_notifier(kvm);
417         if (r) {
418                 cleanup_srcu_struct(&kvm->srcu);
419                 goto out_err;
420         }
421
422         kvm->mm = current->mm;
423         atomic_inc(&kvm->mm->mm_count);
424         spin_lock_init(&kvm->mmu_lock);
425         raw_spin_lock_init(&kvm->requests_lock);
426         kvm_eventfd_init(kvm);
427         mutex_init(&kvm->lock);
428         mutex_init(&kvm->irq_lock);
429         mutex_init(&kvm->slots_lock);
430         atomic_set(&kvm->users_count, 1);
431         spin_lock(&kvm_lock);
432         list_add(&kvm->vm_list, &vm_list);
433         spin_unlock(&kvm_lock);
434 out:
435         return kvm;
436
437 out_err:
438         hardware_disable_all();
439 out_err_nodisable:
440         for (i = 0; i < KVM_NR_BUSES; i++)
441                 kfree(kvm->buses[i]);
442         kfree(kvm->memslots);
443         kfree(kvm);
444         return ERR_PTR(r);
445 }
446
447 static void kvm_destroy_dirty_bitmap(struct kvm_memory_slot *memslot)
448 {
449         if (!memslot->dirty_bitmap)
450                 return;
451
452         vfree(memslot->dirty_bitmap);
453         memslot->dirty_bitmap = NULL;
454 }
455
456 /*
457  * Free any memory in @free but not in @dont.
458  */
459 static void kvm_free_physmem_slot(struct kvm_memory_slot *free,
460                                   struct kvm_memory_slot *dont)
461 {
462         int i;
463
464         if (!dont || free->rmap != dont->rmap)
465                 vfree(free->rmap);
466
467         if (!dont || free->dirty_bitmap != dont->dirty_bitmap)
468                 kvm_destroy_dirty_bitmap(free);
469
470
471         for (i = 0; i < KVM_NR_PAGE_SIZES - 1; ++i) {
472                 if (!dont || free->lpage_info[i] != dont->lpage_info[i]) {
473                         vfree(free->lpage_info[i]);
474                         free->lpage_info[i] = NULL;
475                 }
476         }
477
478         free->npages = 0;
479         free->rmap = NULL;
480 }
481
482 void kvm_free_physmem(struct kvm *kvm)
483 {
484         int i;
485         struct kvm_memslots *slots = kvm->memslots;
486
487         for (i = 0; i < slots->nmemslots; ++i)
488                 kvm_free_physmem_slot(&slots->memslots[i], NULL);
489
490         kfree(kvm->memslots);
491 }
492
493 static void kvm_destroy_vm(struct kvm *kvm)
494 {
495         int i;
496         struct mm_struct *mm = kvm->mm;
497
498         kvm_arch_sync_events(kvm);
499         spin_lock(&kvm_lock);
500         list_del(&kvm->vm_list);
501         spin_unlock(&kvm_lock);
502         kvm_free_irq_routing(kvm);
503         for (i = 0; i < KVM_NR_BUSES; i++)
504                 kvm_io_bus_destroy(kvm->buses[i]);
505         kvm_coalesced_mmio_free(kvm);
506 #if defined(CONFIG_MMU_NOTIFIER) && defined(KVM_ARCH_WANT_MMU_NOTIFIER)
507         mmu_notifier_unregister(&kvm->mmu_notifier, kvm->mm);
508 #else
509         kvm_arch_flush_shadow(kvm);
510 #endif
511         kvm_arch_destroy_vm(kvm);
512         hardware_disable_all();
513         mmdrop(mm);
514 }
515
516 void kvm_get_kvm(struct kvm *kvm)
517 {
518         atomic_inc(&kvm->users_count);
519 }
520 EXPORT_SYMBOL_GPL(kvm_get_kvm);
521
522 void kvm_put_kvm(struct kvm *kvm)
523 {
524         if (atomic_dec_and_test(&kvm->users_count))
525                 kvm_destroy_vm(kvm);
526 }
527 EXPORT_SYMBOL_GPL(kvm_put_kvm);
528
529
530 static int kvm_vm_release(struct inode *inode, struct file *filp)
531 {
532         struct kvm *kvm = filp->private_data;
533
534         kvm_irqfd_release(kvm);
535
536         kvm_put_kvm(kvm);
537         return 0;
538 }
539
540 static int kvm_create_dirty_bitmap(struct kvm_memory_slot *memslot)
541 {
542         unsigned long dirty_bytes = kvm_dirty_bitmap_bytes(memslot);
543
544         memslot->dirty_bitmap = vmalloc(dirty_bytes);
545         if (!memslot->dirty_bitmap)
546                 return -ENOMEM;
547
548         memset(memslot->dirty_bitmap, 0, dirty_bytes);
549         return 0;
550 }
551
552 /*
553  * Allocate some memory and give it an address in the guest physical address
554  * space.
555  *
556  * Discontiguous memory is allowed, mostly for framebuffers.
557  *
558  * Must be called holding mmap_sem for write.
559  */
560 int __kvm_set_memory_region(struct kvm *kvm,
561                             struct kvm_userspace_memory_region *mem,
562                             int user_alloc)
563 {
564         int r, flush_shadow = 0;
565         gfn_t base_gfn;
566         unsigned long npages;
567         unsigned long i;
568         struct kvm_memory_slot *memslot;
569         struct kvm_memory_slot old, new;
570         struct kvm_memslots *slots, *old_memslots;
571
572         r = -EINVAL;
573         /* General sanity checks */
574         if (mem->memory_size & (PAGE_SIZE - 1))
575                 goto out;
576         if (mem->guest_phys_addr & (PAGE_SIZE - 1))
577                 goto out;
578         if (user_alloc && (mem->userspace_addr & (PAGE_SIZE - 1)))
579                 goto out;
580         if (mem->slot >= KVM_MEMORY_SLOTS + KVM_PRIVATE_MEM_SLOTS)
581                 goto out;
582         if (mem->guest_phys_addr + mem->memory_size < mem->guest_phys_addr)
583                 goto out;
584
585         memslot = &kvm->memslots->memslots[mem->slot];
586         base_gfn = mem->guest_phys_addr >> PAGE_SHIFT;
587         npages = mem->memory_size >> PAGE_SHIFT;
588
589         r = -EINVAL;
590         if (npages > KVM_MEM_MAX_NR_PAGES)
591                 goto out;
592
593         if (!npages)
594                 mem->flags &= ~KVM_MEM_LOG_DIRTY_PAGES;
595
596         new = old = *memslot;
597
598         new.id = mem->slot;
599         new.base_gfn = base_gfn;
600         new.npages = npages;
601         new.flags = mem->flags;
602
603         /* Disallow changing a memory slot's size. */
604         r = -EINVAL;
605         if (npages && old.npages && npages != old.npages)
606                 goto out_free;
607
608         /* Check for overlaps */
609         r = -EEXIST;
610         for (i = 0; i < KVM_MEMORY_SLOTS; ++i) {
611                 struct kvm_memory_slot *s = &kvm->memslots->memslots[i];
612
613                 if (s == memslot || !s->npages)
614                         continue;
615                 if (!((base_gfn + npages <= s->base_gfn) ||
616                       (base_gfn >= s->base_gfn + s->npages)))
617                         goto out_free;
618         }
619
620         /* Free page dirty bitmap if unneeded */
621         if (!(new.flags & KVM_MEM_LOG_DIRTY_PAGES))
622                 new.dirty_bitmap = NULL;
623
624         r = -ENOMEM;
625
626         /* Allocate if a slot is being created */
627 #ifndef CONFIG_S390
628         if (npages && !new.rmap) {
629                 new.rmap = vmalloc(npages * sizeof(*new.rmap));
630
631                 if (!new.rmap)
632                         goto out_free;
633
634                 memset(new.rmap, 0, npages * sizeof(*new.rmap));
635
636                 new.user_alloc = user_alloc;
637                 new.userspace_addr = mem->userspace_addr;
638         }
639         if (!npages)
640                 goto skip_lpage;
641
642         for (i = 0; i < KVM_NR_PAGE_SIZES - 1; ++i) {
643                 unsigned long ugfn;
644                 unsigned long j;
645                 int lpages;
646                 int level = i + 2;
647
648                 /* Avoid unused variable warning if no large pages */
649                 (void)level;
650
651                 if (new.lpage_info[i])
652                         continue;
653
654                 lpages = 1 + ((base_gfn + npages - 1)
655                              >> KVM_HPAGE_GFN_SHIFT(level));
656                 lpages -= base_gfn >> KVM_HPAGE_GFN_SHIFT(level);
657
658                 new.lpage_info[i] = vmalloc(lpages * sizeof(*new.lpage_info[i]));
659
660                 if (!new.lpage_info[i])
661                         goto out_free;
662
663                 memset(new.lpage_info[i], 0,
664                        lpages * sizeof(*new.lpage_info[i]));
665
666                 if (base_gfn & (KVM_PAGES_PER_HPAGE(level) - 1))
667                         new.lpage_info[i][0].write_count = 1;
668                 if ((base_gfn+npages) & (KVM_PAGES_PER_HPAGE(level) - 1))
669                         new.lpage_info[i][lpages - 1].write_count = 1;
670                 ugfn = new.userspace_addr >> PAGE_SHIFT;
671                 /*
672                  * If the gfn and userspace address are not aligned wrt each
673                  * other, or if explicitly asked to, disable large page
674                  * support for this slot
675                  */
676                 if ((base_gfn ^ ugfn) & (KVM_PAGES_PER_HPAGE(level) - 1) ||
677                     !largepages_enabled)
678                         for (j = 0; j < lpages; ++j)
679                                 new.lpage_info[i][j].write_count = 1;
680         }
681
682 skip_lpage:
683
684         /* Allocate page dirty bitmap if needed */
685         if ((new.flags & KVM_MEM_LOG_DIRTY_PAGES) && !new.dirty_bitmap) {
686                 if (kvm_create_dirty_bitmap(&new) < 0)
687                         goto out_free;
688                 /* destroy any largepage mappings for dirty tracking */
689                 if (old.npages)
690                         flush_shadow = 1;
691         }
692 #else  /* not defined CONFIG_S390 */
693         new.user_alloc = user_alloc;
694         if (user_alloc)
695                 new.userspace_addr = mem->userspace_addr;
696 #endif /* not defined CONFIG_S390 */
697
698         if (!npages) {
699                 r = -ENOMEM;
700                 slots = kzalloc(sizeof(struct kvm_memslots), GFP_KERNEL);
701                 if (!slots)
702                         goto out_free;
703                 memcpy(slots, kvm->memslots, sizeof(struct kvm_memslots));
704                 if (mem->slot >= slots->nmemslots)
705                         slots->nmemslots = mem->slot + 1;
706                 slots->generation++;
707                 slots->memslots[mem->slot].flags |= KVM_MEMSLOT_INVALID;
708
709                 old_memslots = kvm->memslots;
710                 rcu_assign_pointer(kvm->memslots, slots);
711                 synchronize_srcu_expedited(&kvm->srcu);
712                 /* From this point no new shadow pages pointing to a deleted
713                  * memslot will be created.
714                  *
715                  * validation of sp->gfn happens in:
716                  *      - gfn_to_hva (kvm_read_guest, gfn_to_pfn)
717                  *      - kvm_is_visible_gfn (mmu_check_roots)
718                  */
719                 kvm_arch_flush_shadow(kvm);
720                 kfree(old_memslots);
721         }
722
723         r = kvm_arch_prepare_memory_region(kvm, &new, old, mem, user_alloc);
724         if (r)
725                 goto out_free;
726
727         /* map the pages in iommu page table */
728         if (npages) {
729                 r = kvm_iommu_map_pages(kvm, &new);
730                 if (r)
731                         goto out_free;
732         }
733
734         r = -ENOMEM;
735         slots = kzalloc(sizeof(struct kvm_memslots), GFP_KERNEL);
736         if (!slots)
737                 goto out_free;
738         memcpy(slots, kvm->memslots, sizeof(struct kvm_memslots));
739         if (mem->slot >= slots->nmemslots)
740                 slots->nmemslots = mem->slot + 1;
741         slots->generation++;
742
743         /* actual memory is freed via old in kvm_free_physmem_slot below */
744         if (!npages) {
745                 new.rmap = NULL;
746                 new.dirty_bitmap = NULL;
747                 for (i = 0; i < KVM_NR_PAGE_SIZES - 1; ++i)
748                         new.lpage_info[i] = NULL;
749         }
750
751         slots->memslots[mem->slot] = new;
752         old_memslots = kvm->memslots;
753         rcu_assign_pointer(kvm->memslots, slots);
754         synchronize_srcu_expedited(&kvm->srcu);
755
756         kvm_arch_commit_memory_region(kvm, mem, old, user_alloc);
757
758         kvm_free_physmem_slot(&old, &new);
759         kfree(old_memslots);
760
761         if (flush_shadow)
762                 kvm_arch_flush_shadow(kvm);
763
764         return 0;
765
766 out_free:
767         kvm_free_physmem_slot(&new, &old);
768 out:
769         return r;
770
771 }
772 EXPORT_SYMBOL_GPL(__kvm_set_memory_region);
773
774 int kvm_set_memory_region(struct kvm *kvm,
775                           struct kvm_userspace_memory_region *mem,
776                           int user_alloc)
777 {
778         int r;
779
780         mutex_lock(&kvm->slots_lock);
781         r = __kvm_set_memory_region(kvm, mem, user_alloc);
782         mutex_unlock(&kvm->slots_lock);
783         return r;
784 }
785 EXPORT_SYMBOL_GPL(kvm_set_memory_region);
786
787 int kvm_vm_ioctl_set_memory_region(struct kvm *kvm,
788                                    struct
789                                    kvm_userspace_memory_region *mem,
790                                    int user_alloc)
791 {
792         if (mem->slot >= KVM_MEMORY_SLOTS)
793                 return -EINVAL;
794         return kvm_set_memory_region(kvm, mem, user_alloc);
795 }
796
797 int kvm_get_dirty_log(struct kvm *kvm,
798                         struct kvm_dirty_log *log, int *is_dirty)
799 {
800         struct kvm_memory_slot *memslot;
801         int r, i;
802         unsigned long n;
803         unsigned long any = 0;
804
805         r = -EINVAL;
806         if (log->slot >= KVM_MEMORY_SLOTS)
807                 goto out;
808
809         memslot = &kvm->memslots->memslots[log->slot];
810         r = -ENOENT;
811         if (!memslot->dirty_bitmap)
812                 goto out;
813
814         n = kvm_dirty_bitmap_bytes(memslot);
815
816         for (i = 0; !any && i < n/sizeof(long); ++i)
817                 any = memslot->dirty_bitmap[i];
818
819         r = -EFAULT;
820         if (copy_to_user(log->dirty_bitmap, memslot->dirty_bitmap, n))
821                 goto out;
822
823         if (any)
824                 *is_dirty = 1;
825
826         r = 0;
827 out:
828         return r;
829 }
830
831 void kvm_disable_largepages(void)
832 {
833         largepages_enabled = false;
834 }
835 EXPORT_SYMBOL_GPL(kvm_disable_largepages);
836
837 int is_error_page(struct page *page)
838 {
839         return page == bad_page || page == hwpoison_page || page == fault_page;
840 }
841 EXPORT_SYMBOL_GPL(is_error_page);
842
843 int is_error_pfn(pfn_t pfn)
844 {
845         return pfn == bad_pfn || pfn == hwpoison_pfn || pfn == fault_pfn;
846 }
847 EXPORT_SYMBOL_GPL(is_error_pfn);
848
849 int is_hwpoison_pfn(pfn_t pfn)
850 {
851         return pfn == hwpoison_pfn;
852 }
853 EXPORT_SYMBOL_GPL(is_hwpoison_pfn);
854
855 int is_fault_pfn(pfn_t pfn)
856 {
857         return pfn == fault_pfn;
858 }
859 EXPORT_SYMBOL_GPL(is_fault_pfn);
860
861 static inline unsigned long bad_hva(void)
862 {
863         return PAGE_OFFSET;
864 }
865
866 int kvm_is_error_hva(unsigned long addr)
867 {
868         return addr == bad_hva();
869 }
870 EXPORT_SYMBOL_GPL(kvm_is_error_hva);
871
872 static struct kvm_memory_slot *__gfn_to_memslot(struct kvm_memslots *slots,
873                                                 gfn_t gfn)
874 {
875         int i;
876
877         for (i = 0; i < slots->nmemslots; ++i) {
878                 struct kvm_memory_slot *memslot = &slots->memslots[i];
879
880                 if (gfn >= memslot->base_gfn
881                     && gfn < memslot->base_gfn + memslot->npages)
882                         return memslot;
883         }
884         return NULL;
885 }
886
887 struct kvm_memory_slot *gfn_to_memslot(struct kvm *kvm, gfn_t gfn)
888 {
889         return __gfn_to_memslot(kvm_memslots(kvm), gfn);
890 }
891 EXPORT_SYMBOL_GPL(gfn_to_memslot);
892
893 int kvm_is_visible_gfn(struct kvm *kvm, gfn_t gfn)
894 {
895         int i;
896         struct kvm_memslots *slots = kvm_memslots(kvm);
897
898         for (i = 0; i < KVM_MEMORY_SLOTS; ++i) {
899                 struct kvm_memory_slot *memslot = &slots->memslots[i];
900
901                 if (memslot->flags & KVM_MEMSLOT_INVALID)
902                         continue;
903
904                 if (gfn >= memslot->base_gfn
905                     && gfn < memslot->base_gfn + memslot->npages)
906                         return 1;
907         }
908         return 0;
909 }
910 EXPORT_SYMBOL_GPL(kvm_is_visible_gfn);
911
912 unsigned long kvm_host_page_size(struct kvm *kvm, gfn_t gfn)
913 {
914         struct vm_area_struct *vma;
915         unsigned long addr, size;
916
917         size = PAGE_SIZE;
918
919         addr = gfn_to_hva(kvm, gfn);
920         if (kvm_is_error_hva(addr))
921                 return PAGE_SIZE;
922
923         down_read(&current->mm->mmap_sem);
924         vma = find_vma(current->mm, addr);
925         if (!vma)
926                 goto out;
927
928         size = vma_kernel_pagesize(vma);
929
930 out:
931         up_read(&current->mm->mmap_sem);
932
933         return size;
934 }
935
936 int memslot_id(struct kvm *kvm, gfn_t gfn)
937 {
938         int i;
939         struct kvm_memslots *slots = kvm_memslots(kvm);
940         struct kvm_memory_slot *memslot = NULL;
941
942         for (i = 0; i < slots->nmemslots; ++i) {
943                 memslot = &slots->memslots[i];
944
945                 if (gfn >= memslot->base_gfn
946                     && gfn < memslot->base_gfn + memslot->npages)
947                         break;
948         }
949
950         return memslot - slots->memslots;
951 }
952
953 static unsigned long gfn_to_hva_many(struct kvm_memory_slot *slot, gfn_t gfn,
954                                      gfn_t *nr_pages)
955 {
956         if (!slot || slot->flags & KVM_MEMSLOT_INVALID)
957                 return bad_hva();
958
959         if (nr_pages)
960                 *nr_pages = slot->npages - (gfn - slot->base_gfn);
961
962         return gfn_to_hva_memslot(slot, gfn);
963 }
964
965 unsigned long gfn_to_hva(struct kvm *kvm, gfn_t gfn)
966 {
967         return gfn_to_hva_many(gfn_to_memslot(kvm, gfn), gfn, NULL);
968 }
969 EXPORT_SYMBOL_GPL(gfn_to_hva);
970
971 static pfn_t get_fault_pfn(void)
972 {
973         get_page(fault_page);
974         return fault_pfn;
975 }
976
977 static pfn_t hva_to_pfn(struct kvm *kvm, unsigned long addr, bool atomic,
978                         bool *async, bool write_fault, bool *writable)
979 {
980         struct page *page[1];
981         int npages = 0;
982         pfn_t pfn;
983
984         /* we can do it either atomically or asynchronously, not both */
985         BUG_ON(atomic && async);
986
987         BUG_ON(!write_fault && !writable);
988
989         if (writable)
990                 *writable = true;
991
992         if (atomic || async)
993                 npages = __get_user_pages_fast(addr, 1, 1, page);
994
995         if (unlikely(npages != 1) && !atomic) {
996                 might_sleep();
997
998                 if (writable)
999                         *writable = write_fault;
1000
1001                 npages = get_user_pages_fast(addr, 1, write_fault, page);
1002
1003                 /* map read fault as writable if possible */
1004                 if (unlikely(!write_fault) && npages == 1) {
1005                         struct page *wpage[1];
1006
1007                         npages = __get_user_pages_fast(addr, 1, 1, wpage);
1008                         if (npages == 1) {
1009                                 *writable = true;
1010                                 put_page(page[0]);
1011                                 page[0] = wpage[0];
1012                         }
1013                         npages = 1;
1014                 }
1015         }
1016
1017         if (unlikely(npages != 1)) {
1018                 struct vm_area_struct *vma;
1019
1020                 if (atomic)
1021                         return get_fault_pfn();
1022
1023                 down_read(&current->mm->mmap_sem);
1024                 if (is_hwpoison_address(addr)) {
1025                         up_read(&current->mm->mmap_sem);
1026                         get_page(hwpoison_page);
1027                         return page_to_pfn(hwpoison_page);
1028                 }
1029
1030                 vma = find_vma_intersection(current->mm, addr, addr+1);
1031
1032                 if (vma == NULL)
1033                         pfn = get_fault_pfn();
1034                 else if ((vma->vm_flags & VM_PFNMAP)) {
1035                         pfn = ((addr - vma->vm_start) >> PAGE_SHIFT) +
1036                                 vma->vm_pgoff;
1037                         BUG_ON(!kvm_is_mmio_pfn(pfn));
1038                 } else {
1039                         if (async && (vma->vm_flags & VM_WRITE))
1040                                 *async = true;
1041                         pfn = get_fault_pfn();
1042                 }
1043                 up_read(&current->mm->mmap_sem);
1044         } else
1045                 pfn = page_to_pfn(page[0]);
1046
1047         return pfn;
1048 }
1049
1050 pfn_t hva_to_pfn_atomic(struct kvm *kvm, unsigned long addr)
1051 {
1052         return hva_to_pfn(kvm, addr, true, NULL, true, NULL);
1053 }
1054 EXPORT_SYMBOL_GPL(hva_to_pfn_atomic);
1055
1056 static pfn_t __gfn_to_pfn(struct kvm *kvm, gfn_t gfn, bool atomic, bool *async,
1057                           bool write_fault, bool *writable)
1058 {
1059         unsigned long addr;
1060
1061         if (async)
1062                 *async = false;
1063
1064         addr = gfn_to_hva(kvm, gfn);
1065         if (kvm_is_error_hva(addr)) {
1066                 get_page(bad_page);
1067                 return page_to_pfn(bad_page);
1068         }
1069
1070         return hva_to_pfn(kvm, addr, atomic, async, write_fault, writable);
1071 }
1072
1073 pfn_t gfn_to_pfn_atomic(struct kvm *kvm, gfn_t gfn)
1074 {
1075         return __gfn_to_pfn(kvm, gfn, true, NULL, true, NULL);
1076 }
1077 EXPORT_SYMBOL_GPL(gfn_to_pfn_atomic);
1078
1079 pfn_t gfn_to_pfn_async(struct kvm *kvm, gfn_t gfn, bool *async,
1080                        bool write_fault, bool *writable)
1081 {
1082         return __gfn_to_pfn(kvm, gfn, false, async, write_fault, writable);
1083 }
1084 EXPORT_SYMBOL_GPL(gfn_to_pfn_async);
1085
1086 pfn_t gfn_to_pfn(struct kvm *kvm, gfn_t gfn)
1087 {
1088         return __gfn_to_pfn(kvm, gfn, false, NULL, true, NULL);
1089 }
1090 EXPORT_SYMBOL_GPL(gfn_to_pfn);
1091
1092 pfn_t gfn_to_pfn_prot(struct kvm *kvm, gfn_t gfn, bool write_fault,
1093                       bool *writable)
1094 {
1095         return __gfn_to_pfn(kvm, gfn, false, NULL, write_fault, writable);
1096 }
1097 EXPORT_SYMBOL_GPL(gfn_to_pfn_prot);
1098
1099 pfn_t gfn_to_pfn_memslot(struct kvm *kvm,
1100                          struct kvm_memory_slot *slot, gfn_t gfn)
1101 {
1102         unsigned long addr = gfn_to_hva_memslot(slot, gfn);
1103         return hva_to_pfn(kvm, addr, false, NULL, true, NULL);
1104 }
1105
1106 int gfn_to_page_many_atomic(struct kvm *kvm, gfn_t gfn, struct page **pages,
1107                                                                   int nr_pages)
1108 {
1109         unsigned long addr;
1110         gfn_t entry;
1111
1112         addr = gfn_to_hva_many(gfn_to_memslot(kvm, gfn), gfn, &entry);
1113         if (kvm_is_error_hva(addr))
1114                 return -1;
1115
1116         if (entry < nr_pages)
1117                 return 0;
1118
1119         return __get_user_pages_fast(addr, nr_pages, 1, pages);
1120 }
1121 EXPORT_SYMBOL_GPL(gfn_to_page_many_atomic);
1122
1123 struct page *gfn_to_page(struct kvm *kvm, gfn_t gfn)
1124 {
1125         pfn_t pfn;
1126
1127         pfn = gfn_to_pfn(kvm, gfn);
1128         if (!kvm_is_mmio_pfn(pfn))
1129                 return pfn_to_page(pfn);
1130
1131         WARN_ON(kvm_is_mmio_pfn(pfn));
1132
1133         get_page(bad_page);
1134         return bad_page;
1135 }
1136
1137 EXPORT_SYMBOL_GPL(gfn_to_page);
1138
1139 void kvm_release_page_clean(struct page *page)
1140 {
1141         kvm_release_pfn_clean(page_to_pfn(page));
1142 }
1143 EXPORT_SYMBOL_GPL(kvm_release_page_clean);
1144
1145 void kvm_release_pfn_clean(pfn_t pfn)
1146 {
1147         if (!kvm_is_mmio_pfn(pfn))
1148                 put_page(pfn_to_page(pfn));
1149 }
1150 EXPORT_SYMBOL_GPL(kvm_release_pfn_clean);
1151
1152 void kvm_release_page_dirty(struct page *page)
1153 {
1154         kvm_release_pfn_dirty(page_to_pfn(page));
1155 }
1156 EXPORT_SYMBOL_GPL(kvm_release_page_dirty);
1157
1158 void kvm_release_pfn_dirty(pfn_t pfn)
1159 {
1160         kvm_set_pfn_dirty(pfn);
1161         kvm_release_pfn_clean(pfn);
1162 }
1163 EXPORT_SYMBOL_GPL(kvm_release_pfn_dirty);
1164
1165 void kvm_set_page_dirty(struct page *page)
1166 {
1167         kvm_set_pfn_dirty(page_to_pfn(page));
1168 }
1169 EXPORT_SYMBOL_GPL(kvm_set_page_dirty);
1170
1171 void kvm_set_pfn_dirty(pfn_t pfn)
1172 {
1173         if (!kvm_is_mmio_pfn(pfn)) {
1174                 struct page *page = pfn_to_page(pfn);
1175                 if (!PageReserved(page))
1176                         SetPageDirty(page);
1177         }
1178 }
1179 EXPORT_SYMBOL_GPL(kvm_set_pfn_dirty);
1180
1181 void kvm_set_pfn_accessed(pfn_t pfn)
1182 {
1183         if (!kvm_is_mmio_pfn(pfn))
1184                 mark_page_accessed(pfn_to_page(pfn));
1185 }
1186 EXPORT_SYMBOL_GPL(kvm_set_pfn_accessed);
1187
1188 void kvm_get_pfn(pfn_t pfn)
1189 {
1190         if (!kvm_is_mmio_pfn(pfn))
1191                 get_page(pfn_to_page(pfn));
1192 }
1193 EXPORT_SYMBOL_GPL(kvm_get_pfn);
1194
1195 static int next_segment(unsigned long len, int offset)
1196 {
1197         if (len > PAGE_SIZE - offset)
1198                 return PAGE_SIZE - offset;
1199         else
1200                 return len;
1201 }
1202
1203 int kvm_read_guest_page(struct kvm *kvm, gfn_t gfn, void *data, int offset,
1204                         int len)
1205 {
1206         int r;
1207         unsigned long addr;
1208
1209         addr = gfn_to_hva(kvm, gfn);
1210         if (kvm_is_error_hva(addr))
1211                 return -EFAULT;
1212         r = copy_from_user(data, (void __user *)addr + offset, len);
1213         if (r)
1214                 return -EFAULT;
1215         return 0;
1216 }
1217 EXPORT_SYMBOL_GPL(kvm_read_guest_page);
1218
1219 int kvm_read_guest(struct kvm *kvm, gpa_t gpa, void *data, unsigned long len)
1220 {
1221         gfn_t gfn = gpa >> PAGE_SHIFT;
1222         int seg;
1223         int offset = offset_in_page(gpa);
1224         int ret;
1225
1226         while ((seg = next_segment(len, offset)) != 0) {
1227                 ret = kvm_read_guest_page(kvm, gfn, data, offset, seg);
1228                 if (ret < 0)
1229                         return ret;
1230                 offset = 0;
1231                 len -= seg;
1232                 data += seg;
1233                 ++gfn;
1234         }
1235         return 0;
1236 }
1237 EXPORT_SYMBOL_GPL(kvm_read_guest);
1238
1239 int kvm_read_guest_atomic(struct kvm *kvm, gpa_t gpa, void *data,
1240                           unsigned long len)
1241 {
1242         int r;
1243         unsigned long addr;
1244         gfn_t gfn = gpa >> PAGE_SHIFT;
1245         int offset = offset_in_page(gpa);
1246
1247         addr = gfn_to_hva(kvm, gfn);
1248         if (kvm_is_error_hva(addr))
1249                 return -EFAULT;
1250         pagefault_disable();
1251         r = __copy_from_user_inatomic(data, (void __user *)addr + offset, len);
1252         pagefault_enable();
1253         if (r)
1254                 return -EFAULT;
1255         return 0;
1256 }
1257 EXPORT_SYMBOL(kvm_read_guest_atomic);
1258
1259 int kvm_write_guest_page(struct kvm *kvm, gfn_t gfn, const void *data,
1260                          int offset, int len)
1261 {
1262         int r;
1263         unsigned long addr;
1264
1265         addr = gfn_to_hva(kvm, gfn);
1266         if (kvm_is_error_hva(addr))
1267                 return -EFAULT;
1268         r = copy_to_user((void __user *)addr + offset, data, len);
1269         if (r)
1270                 return -EFAULT;
1271         mark_page_dirty(kvm, gfn);
1272         return 0;
1273 }
1274 EXPORT_SYMBOL_GPL(kvm_write_guest_page);
1275
1276 int kvm_write_guest(struct kvm *kvm, gpa_t gpa, const void *data,
1277                     unsigned long len)
1278 {
1279         gfn_t gfn = gpa >> PAGE_SHIFT;
1280         int seg;
1281         int offset = offset_in_page(gpa);
1282         int ret;
1283
1284         while ((seg = next_segment(len, offset)) != 0) {
1285                 ret = kvm_write_guest_page(kvm, gfn, data, offset, seg);
1286                 if (ret < 0)
1287                         return ret;
1288                 offset = 0;
1289                 len -= seg;
1290                 data += seg;
1291                 ++gfn;
1292         }
1293         return 0;
1294 }
1295
1296 int kvm_gfn_to_hva_cache_init(struct kvm *kvm, struct gfn_to_hva_cache *ghc,
1297                               gpa_t gpa)
1298 {
1299         struct kvm_memslots *slots = kvm_memslots(kvm);
1300         int offset = offset_in_page(gpa);
1301         gfn_t gfn = gpa >> PAGE_SHIFT;
1302
1303         ghc->gpa = gpa;
1304         ghc->generation = slots->generation;
1305         ghc->memslot = __gfn_to_memslot(slots, gfn);
1306         ghc->hva = gfn_to_hva_many(ghc->memslot, gfn, NULL);
1307         if (!kvm_is_error_hva(ghc->hva))
1308                 ghc->hva += offset;
1309         else
1310                 return -EFAULT;
1311
1312         return 0;
1313 }
1314 EXPORT_SYMBOL_GPL(kvm_gfn_to_hva_cache_init);
1315
1316 int kvm_write_guest_cached(struct kvm *kvm, struct gfn_to_hva_cache *ghc,
1317                            void *data, unsigned long len)
1318 {
1319         struct kvm_memslots *slots = kvm_memslots(kvm);
1320         int r;
1321
1322         if (slots->generation != ghc->generation)
1323                 kvm_gfn_to_hva_cache_init(kvm, ghc, ghc->gpa);
1324
1325         if (kvm_is_error_hva(ghc->hva))
1326                 return -EFAULT;
1327
1328         r = copy_to_user((void __user *)ghc->hva, data, len);
1329         if (r)
1330                 return -EFAULT;
1331         mark_page_dirty_in_slot(kvm, ghc->memslot, ghc->gpa >> PAGE_SHIFT);
1332
1333         return 0;
1334 }
1335 EXPORT_SYMBOL_GPL(kvm_write_guest_cached);
1336
1337 int kvm_clear_guest_page(struct kvm *kvm, gfn_t gfn, int offset, int len)
1338 {
1339         return kvm_write_guest_page(kvm, gfn, empty_zero_page, offset, len);
1340 }
1341 EXPORT_SYMBOL_GPL(kvm_clear_guest_page);
1342
1343 int kvm_clear_guest(struct kvm *kvm, gpa_t gpa, unsigned long len)
1344 {
1345         gfn_t gfn = gpa >> PAGE_SHIFT;
1346         int seg;
1347         int offset = offset_in_page(gpa);
1348         int ret;
1349
1350         while ((seg = next_segment(len, offset)) != 0) {
1351                 ret = kvm_clear_guest_page(kvm, gfn, offset, seg);
1352                 if (ret < 0)
1353                         return ret;
1354                 offset = 0;
1355                 len -= seg;
1356                 ++gfn;
1357         }
1358         return 0;
1359 }
1360 EXPORT_SYMBOL_GPL(kvm_clear_guest);
1361
1362 void mark_page_dirty_in_slot(struct kvm *kvm, struct kvm_memory_slot *memslot,
1363                              gfn_t gfn)
1364 {
1365         if (memslot && memslot->dirty_bitmap) {
1366                 unsigned long rel_gfn = gfn - memslot->base_gfn;
1367
1368                 generic___set_le_bit(rel_gfn, memslot->dirty_bitmap);
1369         }
1370 }
1371
1372 void mark_page_dirty(struct kvm *kvm, gfn_t gfn)
1373 {
1374         struct kvm_memory_slot *memslot;
1375
1376         memslot = gfn_to_memslot(kvm, gfn);
1377         mark_page_dirty_in_slot(kvm, memslot, gfn);
1378 }
1379
1380 /*
1381  * The vCPU has executed a HLT instruction with in-kernel mode enabled.
1382  */
1383 void kvm_vcpu_block(struct kvm_vcpu *vcpu)
1384 {
1385         DEFINE_WAIT(wait);
1386
1387         for (;;) {
1388                 prepare_to_wait(&vcpu->wq, &wait, TASK_INTERRUPTIBLE);
1389
1390                 if (kvm_arch_vcpu_runnable(vcpu)) {
1391                         kvm_make_request(KVM_REQ_UNHALT, vcpu);
1392                         break;
1393                 }
1394                 if (kvm_cpu_has_pending_timer(vcpu))
1395                         break;
1396                 if (signal_pending(current))
1397                         break;
1398
1399                 schedule();
1400         }
1401
1402         finish_wait(&vcpu->wq, &wait);
1403 }
1404
1405 void kvm_resched(struct kvm_vcpu *vcpu)
1406 {
1407         if (!need_resched())
1408                 return;
1409         cond_resched();
1410 }
1411 EXPORT_SYMBOL_GPL(kvm_resched);
1412
1413 void kvm_vcpu_on_spin(struct kvm_vcpu *vcpu)
1414 {
1415         ktime_t expires;
1416         DEFINE_WAIT(wait);
1417
1418         prepare_to_wait(&vcpu->wq, &wait, TASK_INTERRUPTIBLE);
1419
1420         /* Sleep for 100 us, and hope lock-holder got scheduled */
1421         expires = ktime_add_ns(ktime_get(), 100000UL);
1422         schedule_hrtimeout(&expires, HRTIMER_MODE_ABS);
1423
1424         finish_wait(&vcpu->wq, &wait);
1425 }
1426 EXPORT_SYMBOL_GPL(kvm_vcpu_on_spin);
1427
1428 static int kvm_vcpu_fault(struct vm_area_struct *vma, struct vm_fault *vmf)
1429 {
1430         struct kvm_vcpu *vcpu = vma->vm_file->private_data;
1431         struct page *page;
1432
1433         if (vmf->pgoff == 0)
1434                 page = virt_to_page(vcpu->run);
1435 #ifdef CONFIG_X86
1436         else if (vmf->pgoff == KVM_PIO_PAGE_OFFSET)
1437                 page = virt_to_page(vcpu->arch.pio_data);
1438 #endif
1439 #ifdef KVM_COALESCED_MMIO_PAGE_OFFSET
1440         else if (vmf->pgoff == KVM_COALESCED_MMIO_PAGE_OFFSET)
1441                 page = virt_to_page(vcpu->kvm->coalesced_mmio_ring);
1442 #endif
1443         else
1444                 return VM_FAULT_SIGBUS;
1445         get_page(page);
1446         vmf->page = page;
1447         return 0;
1448 }
1449
1450 static const struct vm_operations_struct kvm_vcpu_vm_ops = {
1451         .fault = kvm_vcpu_fault,
1452 };
1453
1454 static int kvm_vcpu_mmap(struct file *file, struct vm_area_struct *vma)
1455 {
1456         vma->vm_ops = &kvm_vcpu_vm_ops;
1457         return 0;
1458 }
1459
1460 static int kvm_vcpu_release(struct inode *inode, struct file *filp)
1461 {
1462         struct kvm_vcpu *vcpu = filp->private_data;
1463
1464         kvm_put_kvm(vcpu->kvm);
1465         return 0;
1466 }
1467
1468 static struct file_operations kvm_vcpu_fops = {
1469         .release        = kvm_vcpu_release,
1470         .unlocked_ioctl = kvm_vcpu_ioctl,
1471         .compat_ioctl   = kvm_vcpu_ioctl,
1472         .mmap           = kvm_vcpu_mmap,
1473         .llseek         = noop_llseek,
1474 };
1475
1476 /*
1477  * Allocates an inode for the vcpu.
1478  */
1479 static int create_vcpu_fd(struct kvm_vcpu *vcpu)
1480 {
1481         return anon_inode_getfd("kvm-vcpu", &kvm_vcpu_fops, vcpu, O_RDWR);
1482 }
1483
1484 /*
1485  * Creates some virtual cpus.  Good luck creating more than one.
1486  */
1487 static int kvm_vm_ioctl_create_vcpu(struct kvm *kvm, u32 id)
1488 {
1489         int r;
1490         struct kvm_vcpu *vcpu, *v;
1491
1492         vcpu = kvm_arch_vcpu_create(kvm, id);
1493         if (IS_ERR(vcpu))
1494                 return PTR_ERR(vcpu);
1495
1496         preempt_notifier_init(&vcpu->preempt_notifier, &kvm_preempt_ops);
1497
1498         r = kvm_arch_vcpu_setup(vcpu);
1499         if (r)
1500                 return r;
1501
1502         mutex_lock(&kvm->lock);
1503         if (atomic_read(&kvm->online_vcpus) == KVM_MAX_VCPUS) {
1504                 r = -EINVAL;
1505                 goto vcpu_destroy;
1506         }
1507
1508         kvm_for_each_vcpu(r, v, kvm)
1509                 if (v->vcpu_id == id) {
1510                         r = -EEXIST;
1511                         goto vcpu_destroy;
1512                 }
1513
1514         BUG_ON(kvm->vcpus[atomic_read(&kvm->online_vcpus)]);
1515
1516         /* Now it's all set up, let userspace reach it */
1517         kvm_get_kvm(kvm);
1518         r = create_vcpu_fd(vcpu);
1519         if (r < 0) {
1520                 kvm_put_kvm(kvm);
1521                 goto vcpu_destroy;
1522         }
1523
1524         kvm->vcpus[atomic_read(&kvm->online_vcpus)] = vcpu;
1525         smp_wmb();
1526         atomic_inc(&kvm->online_vcpus);
1527
1528 #ifdef CONFIG_KVM_APIC_ARCHITECTURE
1529         if (kvm->bsp_vcpu_id == id)
1530                 kvm->bsp_vcpu = vcpu;
1531 #endif
1532         mutex_unlock(&kvm->lock);
1533         return r;
1534
1535 vcpu_destroy:
1536         mutex_unlock(&kvm->lock);
1537         kvm_arch_vcpu_destroy(vcpu);
1538         return r;
1539 }
1540
1541 static int kvm_vcpu_ioctl_set_sigmask(struct kvm_vcpu *vcpu, sigset_t *sigset)
1542 {
1543         if (sigset) {
1544                 sigdelsetmask(sigset, sigmask(SIGKILL)|sigmask(SIGSTOP));
1545                 vcpu->sigset_active = 1;
1546                 vcpu->sigset = *sigset;
1547         } else
1548                 vcpu->sigset_active = 0;
1549         return 0;
1550 }
1551
1552 static long kvm_vcpu_ioctl(struct file *filp,
1553                            unsigned int ioctl, unsigned long arg)
1554 {
1555         struct kvm_vcpu *vcpu = filp->private_data;
1556         void __user *argp = (void __user *)arg;
1557         int r;
1558         struct kvm_fpu *fpu = NULL;
1559         struct kvm_sregs *kvm_sregs = NULL;
1560
1561         if (vcpu->kvm->mm != current->mm)
1562                 return -EIO;
1563
1564 #if defined(CONFIG_S390) || defined(CONFIG_PPC)
1565         /*
1566          * Special cases: vcpu ioctls that are asynchronous to vcpu execution,
1567          * so vcpu_load() would break it.
1568          */
1569         if (ioctl == KVM_S390_INTERRUPT || ioctl == KVM_INTERRUPT)
1570                 return kvm_arch_vcpu_ioctl(filp, ioctl, arg);
1571 #endif
1572
1573
1574         vcpu_load(vcpu);
1575         switch (ioctl) {
1576         case KVM_RUN:
1577                 r = -EINVAL;
1578                 if (arg)
1579                         goto out;
1580                 r = kvm_arch_vcpu_ioctl_run(vcpu, vcpu->run);
1581                 trace_kvm_userspace_exit(vcpu->run->exit_reason, r);
1582                 break;
1583         case KVM_GET_REGS: {
1584                 struct kvm_regs *kvm_regs;
1585
1586                 r = -ENOMEM;
1587                 kvm_regs = kzalloc(sizeof(struct kvm_regs), GFP_KERNEL);
1588                 if (!kvm_regs)
1589                         goto out;
1590                 r = kvm_arch_vcpu_ioctl_get_regs(vcpu, kvm_regs);
1591                 if (r)
1592                         goto out_free1;
1593                 r = -EFAULT;
1594                 if (copy_to_user(argp, kvm_regs, sizeof(struct kvm_regs)))
1595                         goto out_free1;
1596                 r = 0;
1597 out_free1:
1598                 kfree(kvm_regs);
1599                 break;
1600         }
1601         case KVM_SET_REGS: {
1602                 struct kvm_regs *kvm_regs;
1603
1604                 r = -ENOMEM;
1605                 kvm_regs = kzalloc(sizeof(struct kvm_regs), GFP_KERNEL);
1606                 if (!kvm_regs)
1607                         goto out;
1608                 r = -EFAULT;
1609                 if (copy_from_user(kvm_regs, argp, sizeof(struct kvm_regs)))
1610                         goto out_free2;
1611                 r = kvm_arch_vcpu_ioctl_set_regs(vcpu, kvm_regs);
1612                 if (r)
1613                         goto out_free2;
1614                 r = 0;
1615 out_free2:
1616                 kfree(kvm_regs);
1617                 break;
1618         }
1619         case KVM_GET_SREGS: {
1620                 kvm_sregs = kzalloc(sizeof(struct kvm_sregs), GFP_KERNEL);
1621                 r = -ENOMEM;
1622                 if (!kvm_sregs)
1623                         goto out;
1624                 r = kvm_arch_vcpu_ioctl_get_sregs(vcpu, kvm_sregs);
1625                 if (r)
1626                         goto out;
1627                 r = -EFAULT;
1628                 if (copy_to_user(argp, kvm_sregs, sizeof(struct kvm_sregs)))
1629                         goto out;
1630                 r = 0;
1631                 break;
1632         }
1633         case KVM_SET_SREGS: {
1634                 kvm_sregs = kmalloc(sizeof(struct kvm_sregs), GFP_KERNEL);
1635                 r = -ENOMEM;
1636                 if (!kvm_sregs)
1637                         goto out;
1638                 r = -EFAULT;
1639                 if (copy_from_user(kvm_sregs, argp, sizeof(struct kvm_sregs)))
1640                         goto out;
1641                 r = kvm_arch_vcpu_ioctl_set_sregs(vcpu, kvm_sregs);
1642                 if (r)
1643                         goto out;
1644                 r = 0;
1645                 break;
1646         }
1647         case KVM_GET_MP_STATE: {
1648                 struct kvm_mp_state mp_state;
1649
1650                 r = kvm_arch_vcpu_ioctl_get_mpstate(vcpu, &mp_state);
1651                 if (r)
1652                         goto out;
1653                 r = -EFAULT;
1654                 if (copy_to_user(argp, &mp_state, sizeof mp_state))
1655                         goto out;
1656                 r = 0;
1657                 break;
1658         }
1659         case KVM_SET_MP_STATE: {
1660                 struct kvm_mp_state mp_state;
1661
1662                 r = -EFAULT;
1663                 if (copy_from_user(&mp_state, argp, sizeof mp_state))
1664                         goto out;
1665                 r = kvm_arch_vcpu_ioctl_set_mpstate(vcpu, &mp_state);
1666                 if (r)
1667                         goto out;
1668                 r = 0;
1669                 break;
1670         }
1671         case KVM_TRANSLATE: {
1672                 struct kvm_translation tr;
1673
1674                 r = -EFAULT;
1675                 if (copy_from_user(&tr, argp, sizeof tr))
1676                         goto out;
1677                 r = kvm_arch_vcpu_ioctl_translate(vcpu, &tr);
1678                 if (r)
1679                         goto out;
1680                 r = -EFAULT;
1681                 if (copy_to_user(argp, &tr, sizeof tr))
1682                         goto out;
1683                 r = 0;
1684                 break;
1685         }
1686         case KVM_SET_GUEST_DEBUG: {
1687                 struct kvm_guest_debug dbg;
1688
1689                 r = -EFAULT;
1690                 if (copy_from_user(&dbg, argp, sizeof dbg))
1691                         goto out;
1692                 r = kvm_arch_vcpu_ioctl_set_guest_debug(vcpu, &dbg);
1693                 if (r)
1694                         goto out;
1695                 r = 0;
1696                 break;
1697         }
1698         case KVM_SET_SIGNAL_MASK: {
1699                 struct kvm_signal_mask __user *sigmask_arg = argp;
1700                 struct kvm_signal_mask kvm_sigmask;
1701                 sigset_t sigset, *p;
1702
1703                 p = NULL;
1704                 if (argp) {
1705                         r = -EFAULT;
1706                         if (copy_from_user(&kvm_sigmask, argp,
1707                                            sizeof kvm_sigmask))
1708                                 goto out;
1709                         r = -EINVAL;
1710                         if (kvm_sigmask.len != sizeof sigset)
1711                                 goto out;
1712                         r = -EFAULT;
1713                         if (copy_from_user(&sigset, sigmask_arg->sigset,
1714                                            sizeof sigset))
1715                                 goto out;
1716                         p = &sigset;
1717                 }
1718                 r = kvm_vcpu_ioctl_set_sigmask(vcpu, p);
1719                 break;
1720         }
1721         case KVM_GET_FPU: {
1722                 fpu = kzalloc(sizeof(struct kvm_fpu), GFP_KERNEL);
1723                 r = -ENOMEM;
1724                 if (!fpu)
1725                         goto out;
1726                 r = kvm_arch_vcpu_ioctl_get_fpu(vcpu, fpu);
1727                 if (r)
1728                         goto out;
1729                 r = -EFAULT;
1730                 if (copy_to_user(argp, fpu, sizeof(struct kvm_fpu)))
1731                         goto out;
1732                 r = 0;
1733                 break;
1734         }
1735         case KVM_SET_FPU: {
1736                 fpu = kmalloc(sizeof(struct kvm_fpu), GFP_KERNEL);
1737                 r = -ENOMEM;
1738                 if (!fpu)
1739                         goto out;
1740                 r = -EFAULT;
1741                 if (copy_from_user(fpu, argp, sizeof(struct kvm_fpu)))
1742                         goto out;
1743                 r = kvm_arch_vcpu_ioctl_set_fpu(vcpu, fpu);
1744                 if (r)
1745                         goto out;
1746                 r = 0;
1747                 break;
1748         }
1749         default:
1750                 r = kvm_arch_vcpu_ioctl(filp, ioctl, arg);
1751         }
1752 out:
1753         vcpu_put(vcpu);
1754         kfree(fpu);
1755         kfree(kvm_sregs);
1756         return r;
1757 }
1758
1759 static long kvm_vm_ioctl(struct file *filp,
1760                            unsigned int ioctl, unsigned long arg)
1761 {
1762         struct kvm *kvm = filp->private_data;
1763         void __user *argp = (void __user *)arg;
1764         int r;
1765
1766         if (kvm->mm != current->mm)
1767                 return -EIO;
1768         switch (ioctl) {
1769         case KVM_CREATE_VCPU:
1770                 r = kvm_vm_ioctl_create_vcpu(kvm, arg);
1771                 if (r < 0)
1772                         goto out;
1773                 break;
1774         case KVM_SET_USER_MEMORY_REGION: {
1775                 struct kvm_userspace_memory_region kvm_userspace_mem;
1776
1777                 r = -EFAULT;
1778                 if (copy_from_user(&kvm_userspace_mem, argp,
1779                                                 sizeof kvm_userspace_mem))
1780                         goto out;
1781
1782                 r = kvm_vm_ioctl_set_memory_region(kvm, &kvm_userspace_mem, 1);
1783                 if (r)
1784                         goto out;
1785                 break;
1786         }
1787         case KVM_GET_DIRTY_LOG: {
1788                 struct kvm_dirty_log log;
1789
1790                 r = -EFAULT;
1791                 if (copy_from_user(&log, argp, sizeof log))
1792                         goto out;
1793                 r = kvm_vm_ioctl_get_dirty_log(kvm, &log);
1794                 if (r)
1795                         goto out;
1796                 break;
1797         }
1798 #ifdef KVM_COALESCED_MMIO_PAGE_OFFSET
1799         case KVM_REGISTER_COALESCED_MMIO: {
1800                 struct kvm_coalesced_mmio_zone zone;
1801                 r = -EFAULT;
1802                 if (copy_from_user(&zone, argp, sizeof zone))
1803                         goto out;
1804                 r = kvm_vm_ioctl_register_coalesced_mmio(kvm, &zone);
1805                 if (r)
1806                         goto out;
1807                 r = 0;
1808                 break;
1809         }
1810         case KVM_UNREGISTER_COALESCED_MMIO: {
1811                 struct kvm_coalesced_mmio_zone zone;
1812                 r = -EFAULT;
1813                 if (copy_from_user(&zone, argp, sizeof zone))
1814                         goto out;
1815                 r = kvm_vm_ioctl_unregister_coalesced_mmio(kvm, &zone);
1816                 if (r)
1817                         goto out;
1818                 r = 0;
1819                 break;
1820         }
1821 #endif
1822         case KVM_IRQFD: {
1823                 struct kvm_irqfd data;
1824
1825                 r = -EFAULT;
1826                 if (copy_from_user(&data, argp, sizeof data))
1827                         goto out;
1828                 r = kvm_irqfd(kvm, data.fd, data.gsi, data.flags);
1829                 break;
1830         }
1831         case KVM_IOEVENTFD: {
1832                 struct kvm_ioeventfd data;
1833
1834                 r = -EFAULT;
1835                 if (copy_from_user(&data, argp, sizeof data))
1836                         goto out;
1837                 r = kvm_ioeventfd(kvm, &data);
1838                 break;
1839         }
1840 #ifdef CONFIG_KVM_APIC_ARCHITECTURE
1841         case KVM_SET_BOOT_CPU_ID:
1842                 r = 0;
1843                 mutex_lock(&kvm->lock);
1844                 if (atomic_read(&kvm->online_vcpus) != 0)
1845                         r = -EBUSY;
1846                 else
1847                         kvm->bsp_vcpu_id = arg;
1848                 mutex_unlock(&kvm->lock);
1849                 break;
1850 #endif
1851         default:
1852                 r = kvm_arch_vm_ioctl(filp, ioctl, arg);
1853                 if (r == -ENOTTY)
1854                         r = kvm_vm_ioctl_assigned_device(kvm, ioctl, arg);
1855         }
1856 out:
1857         return r;
1858 }
1859
1860 #ifdef CONFIG_COMPAT
1861 struct compat_kvm_dirty_log {
1862         __u32 slot;
1863         __u32 padding1;
1864         union {
1865                 compat_uptr_t dirty_bitmap; /* one bit per page */
1866                 __u64 padding2;
1867         };
1868 };
1869
1870 static long kvm_vm_compat_ioctl(struct file *filp,
1871                            unsigned int ioctl, unsigned long arg)
1872 {
1873         struct kvm *kvm = filp->private_data;
1874         int r;
1875
1876         if (kvm->mm != current->mm)
1877                 return -EIO;
1878         switch (ioctl) {
1879         case KVM_GET_DIRTY_LOG: {
1880                 struct compat_kvm_dirty_log compat_log;
1881                 struct kvm_dirty_log log;
1882
1883                 r = -EFAULT;
1884                 if (copy_from_user(&compat_log, (void __user *)arg,
1885                                    sizeof(compat_log)))
1886                         goto out;
1887                 log.slot         = compat_log.slot;
1888                 log.padding1     = compat_log.padding1;
1889                 log.padding2     = compat_log.padding2;
1890                 log.dirty_bitmap = compat_ptr(compat_log.dirty_bitmap);
1891
1892                 r = kvm_vm_ioctl_get_dirty_log(kvm, &log);
1893                 if (r)
1894                         goto out;
1895                 break;
1896         }
1897         default:
1898                 r = kvm_vm_ioctl(filp, ioctl, arg);
1899         }
1900
1901 out:
1902         return r;
1903 }
1904 #endif
1905
1906 static int kvm_vm_fault(struct vm_area_struct *vma, struct vm_fault *vmf)
1907 {
1908         struct page *page[1];
1909         unsigned long addr;
1910         int npages;
1911         gfn_t gfn = vmf->pgoff;
1912         struct kvm *kvm = vma->vm_file->private_data;
1913
1914         addr = gfn_to_hva(kvm, gfn);
1915         if (kvm_is_error_hva(addr))
1916                 return VM_FAULT_SIGBUS;
1917
1918         npages = get_user_pages(current, current->mm, addr, 1, 1, 0, page,
1919                                 NULL);
1920         if (unlikely(npages != 1))
1921                 return VM_FAULT_SIGBUS;
1922
1923         vmf->page = page[0];
1924         return 0;
1925 }
1926
1927 static const struct vm_operations_struct kvm_vm_vm_ops = {
1928         .fault = kvm_vm_fault,
1929 };
1930
1931 static int kvm_vm_mmap(struct file *file, struct vm_area_struct *vma)
1932 {
1933         vma->vm_ops = &kvm_vm_vm_ops;
1934         return 0;
1935 }
1936
1937 static struct file_operations kvm_vm_fops = {
1938         .release        = kvm_vm_release,
1939         .unlocked_ioctl = kvm_vm_ioctl,
1940 #ifdef CONFIG_COMPAT
1941         .compat_ioctl   = kvm_vm_compat_ioctl,
1942 #endif
1943         .mmap           = kvm_vm_mmap,
1944         .llseek         = noop_llseek,
1945 };
1946
1947 static int kvm_dev_ioctl_create_vm(void)
1948 {
1949         int fd, r;
1950         struct kvm *kvm;
1951
1952         kvm = kvm_create_vm();
1953         if (IS_ERR(kvm))
1954                 return PTR_ERR(kvm);
1955 #ifdef KVM_COALESCED_MMIO_PAGE_OFFSET
1956         r = kvm_coalesced_mmio_init(kvm);
1957         if (r < 0) {
1958                 kvm_put_kvm(kvm);
1959                 return r;
1960         }
1961 #endif
1962         fd = anon_inode_getfd("kvm-vm", &kvm_vm_fops, kvm, O_RDWR);
1963         if (fd < 0)
1964                 kvm_put_kvm(kvm);
1965
1966         return fd;
1967 }
1968
1969 static long kvm_dev_ioctl_check_extension_generic(long arg)
1970 {
1971         switch (arg) {
1972         case KVM_CAP_USER_MEMORY:
1973         case KVM_CAP_DESTROY_MEMORY_REGION_WORKS:
1974         case KVM_CAP_JOIN_MEMORY_REGIONS_WORKS:
1975 #ifdef CONFIG_KVM_APIC_ARCHITECTURE
1976         case KVM_CAP_SET_BOOT_CPU_ID:
1977 #endif
1978         case KVM_CAP_INTERNAL_ERROR_DATA:
1979                 return 1;
1980 #ifdef CONFIG_HAVE_KVM_IRQCHIP
1981         case KVM_CAP_IRQ_ROUTING:
1982                 return KVM_MAX_IRQ_ROUTES;
1983 #endif
1984         default:
1985                 break;
1986         }
1987         return kvm_dev_ioctl_check_extension(arg);
1988 }
1989
1990 static long kvm_dev_ioctl(struct file *filp,
1991                           unsigned int ioctl, unsigned long arg)
1992 {
1993         long r = -EINVAL;
1994
1995         switch (ioctl) {
1996         case KVM_GET_API_VERSION:
1997                 r = -EINVAL;
1998                 if (arg)
1999                         goto out;
2000                 r = KVM_API_VERSION;
2001                 break;
2002         case KVM_CREATE_VM:
2003                 r = -EINVAL;
2004                 if (arg)
2005                         goto out;
2006                 r = kvm_dev_ioctl_create_vm();
2007                 break;
2008         case KVM_CHECK_EXTENSION:
2009                 r = kvm_dev_ioctl_check_extension_generic(arg);
2010                 break;
2011         case KVM_GET_VCPU_MMAP_SIZE:
2012                 r = -EINVAL;
2013                 if (arg)
2014                         goto out;
2015                 r = PAGE_SIZE;     /* struct kvm_run */
2016 #ifdef CONFIG_X86
2017                 r += PAGE_SIZE;    /* pio data page */
2018 #endif
2019 #ifdef KVM_COALESCED_MMIO_PAGE_OFFSET
2020                 r += PAGE_SIZE;    /* coalesced mmio ring page */
2021 #endif
2022                 break;
2023         case KVM_TRACE_ENABLE:
2024         case KVM_TRACE_PAUSE:
2025         case KVM_TRACE_DISABLE:
2026                 r = -EOPNOTSUPP;
2027                 break;
2028         default:
2029                 return kvm_arch_dev_ioctl(filp, ioctl, arg);
2030         }
2031 out:
2032         return r;
2033 }
2034
2035 static struct file_operations kvm_chardev_ops = {
2036         .unlocked_ioctl = kvm_dev_ioctl,
2037         .compat_ioctl   = kvm_dev_ioctl,
2038         .llseek         = noop_llseek,
2039 };
2040
2041 static struct miscdevice kvm_dev = {
2042         KVM_MINOR,
2043         "kvm",
2044         &kvm_chardev_ops,
2045 };
2046
2047 static void hardware_enable(void *junk)
2048 {
2049         int cpu = raw_smp_processor_id();
2050         int r;
2051
2052         if (cpumask_test_cpu(cpu, cpus_hardware_enabled))
2053                 return;
2054
2055         cpumask_set_cpu(cpu, cpus_hardware_enabled);
2056
2057         r = kvm_arch_hardware_enable(NULL);
2058
2059         if (r) {
2060                 cpumask_clear_cpu(cpu, cpus_hardware_enabled);
2061                 atomic_inc(&hardware_enable_failed);
2062                 printk(KERN_INFO "kvm: enabling virtualization on "
2063                                  "CPU%d failed\n", cpu);
2064         }
2065 }
2066
2067 static void hardware_disable(void *junk)
2068 {
2069         int cpu = raw_smp_processor_id();
2070
2071         if (!cpumask_test_cpu(cpu, cpus_hardware_enabled))
2072                 return;
2073         cpumask_clear_cpu(cpu, cpus_hardware_enabled);
2074         kvm_arch_hardware_disable(NULL);
2075 }
2076
2077 static void hardware_disable_all_nolock(void)
2078 {
2079         BUG_ON(!kvm_usage_count);
2080
2081         kvm_usage_count--;
2082         if (!kvm_usage_count)
2083                 on_each_cpu(hardware_disable, NULL, 1);
2084 }
2085
2086 static void hardware_disable_all(void)
2087 {
2088         spin_lock(&kvm_lock);
2089         hardware_disable_all_nolock();
2090         spin_unlock(&kvm_lock);
2091 }
2092
2093 static int hardware_enable_all(void)
2094 {
2095         int r = 0;
2096
2097         spin_lock(&kvm_lock);
2098
2099         kvm_usage_count++;
2100         if (kvm_usage_count == 1) {
2101                 atomic_set(&hardware_enable_failed, 0);
2102                 on_each_cpu(hardware_enable, NULL, 1);
2103
2104                 if (atomic_read(&hardware_enable_failed)) {
2105                         hardware_disable_all_nolock();
2106                         r = -EBUSY;
2107                 }
2108         }
2109
2110         spin_unlock(&kvm_lock);
2111
2112         return r;
2113 }
2114
2115 static int kvm_cpu_hotplug(struct notifier_block *notifier, unsigned long val,
2116                            void *v)
2117 {
2118         int cpu = (long)v;
2119
2120         if (!kvm_usage_count)
2121                 return NOTIFY_OK;
2122
2123         val &= ~CPU_TASKS_FROZEN;
2124         switch (val) {
2125         case CPU_DYING:
2126                 printk(KERN_INFO "kvm: disabling virtualization on CPU%d\n",
2127                        cpu);
2128                 hardware_disable(NULL);
2129                 break;
2130         case CPU_STARTING:
2131                 printk(KERN_INFO "kvm: enabling virtualization on CPU%d\n",
2132                        cpu);
2133                 spin_lock(&kvm_lock);
2134                 hardware_enable(NULL);
2135                 spin_unlock(&kvm_lock);
2136                 break;
2137         }
2138         return NOTIFY_OK;
2139 }
2140
2141
2142 asmlinkage void kvm_handle_fault_on_reboot(void)
2143 {
2144         if (kvm_rebooting) {
2145                 /* spin while reset goes on */
2146                 local_irq_enable();
2147                 while (true)
2148                         cpu_relax();
2149         }
2150         /* Fault while not rebooting.  We want the trace. */
2151         BUG();
2152 }
2153 EXPORT_SYMBOL_GPL(kvm_handle_fault_on_reboot);
2154
2155 static int kvm_reboot(struct notifier_block *notifier, unsigned long val,
2156                       void *v)
2157 {
2158         /*
2159          * Some (well, at least mine) BIOSes hang on reboot if
2160          * in vmx root mode.
2161          *
2162          * And Intel TXT required VMX off for all cpu when system shutdown.
2163          */
2164         printk(KERN_INFO "kvm: exiting hardware virtualization\n");
2165         kvm_rebooting = true;
2166         on_each_cpu(hardware_disable, NULL, 1);
2167         return NOTIFY_OK;
2168 }
2169
2170 static struct notifier_block kvm_reboot_notifier = {
2171         .notifier_call = kvm_reboot,
2172         .priority = 0,
2173 };
2174
2175 static void kvm_io_bus_destroy(struct kvm_io_bus *bus)
2176 {
2177         int i;
2178
2179         for (i = 0; i < bus->dev_count; i++) {
2180                 struct kvm_io_device *pos = bus->devs[i];
2181
2182                 kvm_iodevice_destructor(pos);
2183         }
2184         kfree(bus);
2185 }
2186
2187 /* kvm_io_bus_write - called under kvm->slots_lock */
2188 int kvm_io_bus_write(struct kvm *kvm, enum kvm_bus bus_idx, gpa_t addr,
2189                      int len, const void *val)
2190 {
2191         int i;
2192         struct kvm_io_bus *bus;
2193
2194         bus = srcu_dereference(kvm->buses[bus_idx], &kvm->srcu);
2195         for (i = 0; i < bus->dev_count; i++)
2196                 if (!kvm_iodevice_write(bus->devs[i], addr, len, val))
2197                         return 0;
2198         return -EOPNOTSUPP;
2199 }
2200
2201 /* kvm_io_bus_read - called under kvm->slots_lock */
2202 int kvm_io_bus_read(struct kvm *kvm, enum kvm_bus bus_idx, gpa_t addr,
2203                     int len, void *val)
2204 {
2205         int i;
2206         struct kvm_io_bus *bus;
2207
2208         bus = srcu_dereference(kvm->buses[bus_idx], &kvm->srcu);
2209         for (i = 0; i < bus->dev_count; i++)
2210                 if (!kvm_iodevice_read(bus->devs[i], addr, len, val))
2211                         return 0;
2212         return -EOPNOTSUPP;
2213 }
2214
2215 /* Caller must hold slots_lock. */
2216 int kvm_io_bus_register_dev(struct kvm *kvm, enum kvm_bus bus_idx,
2217                             struct kvm_io_device *dev)
2218 {
2219         struct kvm_io_bus *new_bus, *bus;
2220
2221         bus = kvm->buses[bus_idx];
2222         if (bus->dev_count > NR_IOBUS_DEVS-1)
2223                 return -ENOSPC;
2224
2225         new_bus = kzalloc(sizeof(struct kvm_io_bus), GFP_KERNEL);
2226         if (!new_bus)
2227                 return -ENOMEM;
2228         memcpy(new_bus, bus, sizeof(struct kvm_io_bus));
2229         new_bus->devs[new_bus->dev_count++] = dev;
2230         rcu_assign_pointer(kvm->buses[bus_idx], new_bus);
2231         synchronize_srcu_expedited(&kvm->srcu);
2232         kfree(bus);
2233
2234         return 0;
2235 }
2236
2237 /* Caller must hold slots_lock. */
2238 int kvm_io_bus_unregister_dev(struct kvm *kvm, enum kvm_bus bus_idx,
2239                               struct kvm_io_device *dev)
2240 {
2241         int i, r;
2242         struct kvm_io_bus *new_bus, *bus;
2243
2244         new_bus = kzalloc(sizeof(struct kvm_io_bus), GFP_KERNEL);
2245         if (!new_bus)
2246                 return -ENOMEM;
2247
2248         bus = kvm->buses[bus_idx];
2249         memcpy(new_bus, bus, sizeof(struct kvm_io_bus));
2250
2251         r = -ENOENT;
2252         for (i = 0; i < new_bus->dev_count; i++)
2253                 if (new_bus->devs[i] == dev) {
2254                         r = 0;
2255                         new_bus->devs[i] = new_bus->devs[--new_bus->dev_count];
2256                         break;
2257                 }
2258
2259         if (r) {
2260                 kfree(new_bus);
2261                 return r;
2262         }
2263
2264         rcu_assign_pointer(kvm->buses[bus_idx], new_bus);
2265         synchronize_srcu_expedited(&kvm->srcu);
2266         kfree(bus);
2267         return r;
2268 }
2269
2270 static struct notifier_block kvm_cpu_notifier = {
2271         .notifier_call = kvm_cpu_hotplug,
2272 };
2273
2274 static int vm_stat_get(void *_offset, u64 *val)
2275 {
2276         unsigned offset = (long)_offset;
2277         struct kvm *kvm;
2278
2279         *val = 0;
2280         spin_lock(&kvm_lock);
2281         list_for_each_entry(kvm, &vm_list, vm_list)
2282                 *val += *(u32 *)((void *)kvm + offset);
2283         spin_unlock(&kvm_lock);
2284         return 0;
2285 }
2286
2287 DEFINE_SIMPLE_ATTRIBUTE(vm_stat_fops, vm_stat_get, NULL, "%llu\n");
2288
2289 static int vcpu_stat_get(void *_offset, u64 *val)
2290 {
2291         unsigned offset = (long)_offset;
2292         struct kvm *kvm;
2293         struct kvm_vcpu *vcpu;
2294         int i;
2295
2296         *val = 0;
2297         spin_lock(&kvm_lock);
2298         list_for_each_entry(kvm, &vm_list, vm_list)
2299                 kvm_for_each_vcpu(i, vcpu, kvm)
2300                         *val += *(u32 *)((void *)vcpu + offset);
2301
2302         spin_unlock(&kvm_lock);
2303         return 0;
2304 }
2305
2306 DEFINE_SIMPLE_ATTRIBUTE(vcpu_stat_fops, vcpu_stat_get, NULL, "%llu\n");
2307
2308 static const struct file_operations *stat_fops[] = {
2309         [KVM_STAT_VCPU] = &vcpu_stat_fops,
2310         [KVM_STAT_VM]   = &vm_stat_fops,
2311 };
2312
2313 static void kvm_init_debug(void)
2314 {
2315         struct kvm_stats_debugfs_item *p;
2316
2317         kvm_debugfs_dir = debugfs_create_dir("kvm", NULL);
2318         for (p = debugfs_entries; p->name; ++p)
2319                 p->dentry = debugfs_create_file(p->name, 0444, kvm_debugfs_dir,
2320                                                 (void *)(long)p->offset,
2321                                                 stat_fops[p->kind]);
2322 }
2323
2324 static void kvm_exit_debug(void)
2325 {
2326         struct kvm_stats_debugfs_item *p;
2327
2328         for (p = debugfs_entries; p->name; ++p)
2329                 debugfs_remove(p->dentry);
2330         debugfs_remove(kvm_debugfs_dir);
2331 }
2332
2333 static int kvm_suspend(struct sys_device *dev, pm_message_t state)
2334 {
2335         if (kvm_usage_count)
2336                 hardware_disable(NULL);
2337         return 0;
2338 }
2339
2340 static int kvm_resume(struct sys_device *dev)
2341 {
2342         if (kvm_usage_count) {
2343                 WARN_ON(spin_is_locked(&kvm_lock));
2344                 hardware_enable(NULL);
2345         }
2346         return 0;
2347 }
2348
2349 static struct sysdev_class kvm_sysdev_class = {
2350         .name = "kvm",
2351         .suspend = kvm_suspend,
2352         .resume = kvm_resume,
2353 };
2354
2355 static struct sys_device kvm_sysdev = {
2356         .id = 0,
2357         .cls = &kvm_sysdev_class,
2358 };
2359
2360 struct page *bad_page;
2361 pfn_t bad_pfn;
2362
2363 static inline
2364 struct kvm_vcpu *preempt_notifier_to_vcpu(struct preempt_notifier *pn)
2365 {
2366         return container_of(pn, struct kvm_vcpu, preempt_notifier);
2367 }
2368
2369 static void kvm_sched_in(struct preempt_notifier *pn, int cpu)
2370 {
2371         struct kvm_vcpu *vcpu = preempt_notifier_to_vcpu(pn);
2372
2373         kvm_arch_vcpu_load(vcpu, cpu);
2374 }
2375
2376 static void kvm_sched_out(struct preempt_notifier *pn,
2377                           struct task_struct *next)
2378 {
2379         struct kvm_vcpu *vcpu = preempt_notifier_to_vcpu(pn);
2380
2381         kvm_arch_vcpu_put(vcpu);
2382 }
2383
2384 int kvm_init(void *opaque, unsigned vcpu_size, unsigned vcpu_align,
2385                   struct module *module)
2386 {
2387         int r;
2388         int cpu;
2389
2390         r = kvm_arch_init(opaque);
2391         if (r)
2392                 goto out_fail;
2393
2394         bad_page = alloc_page(GFP_KERNEL | __GFP_ZERO);
2395
2396         if (bad_page == NULL) {
2397                 r = -ENOMEM;
2398                 goto out;
2399         }
2400
2401         bad_pfn = page_to_pfn(bad_page);
2402
2403         hwpoison_page = alloc_page(GFP_KERNEL | __GFP_ZERO);
2404
2405         if (hwpoison_page == NULL) {
2406                 r = -ENOMEM;
2407                 goto out_free_0;
2408         }
2409
2410         hwpoison_pfn = page_to_pfn(hwpoison_page);
2411
2412         fault_page = alloc_page(GFP_KERNEL | __GFP_ZERO);
2413
2414         if (fault_page == NULL) {
2415                 r = -ENOMEM;
2416                 goto out_free_0;
2417         }
2418
2419         fault_pfn = page_to_pfn(fault_page);
2420
2421         if (!zalloc_cpumask_var(&cpus_hardware_enabled, GFP_KERNEL)) {
2422                 r = -ENOMEM;
2423                 goto out_free_0;
2424         }
2425
2426         r = kvm_arch_hardware_setup();
2427         if (r < 0)
2428                 goto out_free_0a;
2429
2430         for_each_online_cpu(cpu) {
2431                 smp_call_function_single(cpu,
2432                                 kvm_arch_check_processor_compat,
2433                                 &r, 1);
2434                 if (r < 0)
2435                         goto out_free_1;
2436         }
2437
2438         r = register_cpu_notifier(&kvm_cpu_notifier);
2439         if (r)
2440                 goto out_free_2;
2441         register_reboot_notifier(&kvm_reboot_notifier);
2442
2443         r = sysdev_class_register(&kvm_sysdev_class);
2444         if (r)
2445                 goto out_free_3;
2446
2447         r = sysdev_register(&kvm_sysdev);
2448         if (r)
2449                 goto out_free_4;
2450
2451         /* A kmem cache lets us meet the alignment requirements of fx_save. */
2452         if (!vcpu_align)
2453                 vcpu_align = __alignof__(struct kvm_vcpu);
2454         kvm_vcpu_cache = kmem_cache_create("kvm_vcpu", vcpu_size, vcpu_align,
2455                                            0, NULL);
2456         if (!kvm_vcpu_cache) {
2457                 r = -ENOMEM;
2458                 goto out_free_5;
2459         }
2460
2461         r = kvm_async_pf_init();
2462         if (r)
2463                 goto out_free;
2464
2465         kvm_chardev_ops.owner = module;
2466         kvm_vm_fops.owner = module;
2467         kvm_vcpu_fops.owner = module;
2468
2469         r = misc_register(&kvm_dev);
2470         if (r) {
2471                 printk(KERN_ERR "kvm: misc device register failed\n");
2472                 goto out_unreg;
2473         }
2474
2475         kvm_preempt_ops.sched_in = kvm_sched_in;
2476         kvm_preempt_ops.sched_out = kvm_sched_out;
2477
2478         kvm_init_debug();
2479
2480         return 0;
2481
2482 out_unreg:
2483         kvm_async_pf_deinit();
2484 out_free:
2485         kmem_cache_destroy(kvm_vcpu_cache);
2486 out_free_5:
2487         sysdev_unregister(&kvm_sysdev);
2488 out_free_4:
2489         sysdev_class_unregister(&kvm_sysdev_class);
2490 out_free_3:
2491         unregister_reboot_notifier(&kvm_reboot_notifier);
2492         unregister_cpu_notifier(&kvm_cpu_notifier);
2493 out_free_2:
2494 out_free_1:
2495         kvm_arch_hardware_unsetup();
2496 out_free_0a:
2497         free_cpumask_var(cpus_hardware_enabled);
2498 out_free_0:
2499         if (fault_page)
2500                 __free_page(fault_page);
2501         if (hwpoison_page)
2502                 __free_page(hwpoison_page);
2503         __free_page(bad_page);
2504 out:
2505         kvm_arch_exit();
2506 out_fail:
2507         return r;
2508 }
2509 EXPORT_SYMBOL_GPL(kvm_init);
2510
2511 void kvm_exit(void)
2512 {
2513         kvm_exit_debug();
2514         misc_deregister(&kvm_dev);
2515         kmem_cache_destroy(kvm_vcpu_cache);
2516         kvm_async_pf_deinit();
2517         sysdev_unregister(&kvm_sysdev);
2518         sysdev_class_unregister(&kvm_sysdev_class);
2519         unregister_reboot_notifier(&kvm_reboot_notifier);
2520         unregister_cpu_notifier(&kvm_cpu_notifier);
2521         on_each_cpu(hardware_disable, NULL, 1);
2522         kvm_arch_hardware_unsetup();
2523         kvm_arch_exit();
2524         free_cpumask_var(cpus_hardware_enabled);
2525         __free_page(hwpoison_page);
2526         __free_page(bad_page);
2527 }
2528 EXPORT_SYMBOL_GPL(kvm_exit);