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KVM: MMU: collapse TLB flushes when zap all pages
[linux-2.6/btrfs-unstable.git] / virt / kvm / kvm_main.c
blob1580dd4ace4eac20b37043c2f5c882349204ed4a
1 /*
2 * Kernel-based Virtual Machine driver for Linux
3 *
4 * This module enables machines with Intel VT-x extensions to run virtual
5 * machines without emulation or binary translation.
6 *
7 * Copyright (C) 2006 Qumranet, Inc.
8 * Copyright 2010 Red Hat, Inc. and/or its affiliates.
9 *
10 * Authors:
11 * Avi Kivity <avi@qumranet.com>
12 * Yaniv Kamay <yaniv@qumranet.com>
13 *
14 * This work is licensed under the terms of the GNU GPL, version 2. See
15 * the COPYING file in the top-level directory.
16 *
17 */
18
19 #include "iodev.h"
20
21 #include <linux/kvm_host.h>
22 #include <linux/kvm.h>
23 #include <linux/module.h>
24 #include <linux/errno.h>
25 #include <linux/percpu.h>
26 #include <linux/mm.h>
27 #include <linux/miscdevice.h>
28 #include <linux/vmalloc.h>
29 #include <linux/reboot.h>
30 #include <linux/debugfs.h>
31 #include <linux/highmem.h>
32 #include <linux/file.h>
33 #include <linux/syscore_ops.h>
34 #include <linux/cpu.h>
35 #include <linux/sched.h>
36 #include <linux/cpumask.h>
37 #include <linux/smp.h>
38 #include <linux/anon_inodes.h>
39 #include <linux/profile.h>
40 #include <linux/kvm_para.h>
41 #include <linux/pagemap.h>
42 #include <linux/mman.h>
43 #include <linux/swap.h>
44 #include <linux/bitops.h>
45 #include <linux/spinlock.h>
46 #include <linux/compat.h>
47 #include <linux/srcu.h>
48 #include <linux/hugetlb.h>
49 #include <linux/slab.h>
50 #include <linux/sort.h>
51 #include <linux/bsearch.h>
52
53 #include <asm/processor.h>
54 #include <asm/io.h>
55 #include <asm/uaccess.h>
56 #include <asm/pgtable.h>
57
58 #include "coalesced_mmio.h"
59 #include "async_pf.h"
60
61 #define CREATE_TRACE_POINTS
62 #include <trace/events/kvm.h>
63
64 MODULE_AUTHOR("Qumranet");
65 MODULE_LICENSE("GPL");
66
67 /*
68 * Ordering of locks:
69 *
70 * kvm->lock --> kvm->slots_lock --> kvm->irq_lock
71 */
72
73 DEFINE_RAW_SPINLOCK(kvm_lock);
74 LIST_HEAD(vm_list);
75
76 static cpumask_var_t cpus_hardware_enabled;
77 static int kvm_usage_count = 0;
78 static atomic_t hardware_enable_failed;
79
80 struct kmem_cache *kvm_vcpu_cache;
81 EXPORT_SYMBOL_GPL(kvm_vcpu_cache);
82
83 static __read_mostly struct preempt_ops kvm_preempt_ops;
84
85 struct dentry *kvm_debugfs_dir;
86
87 static long kvm_vcpu_ioctl(struct file *file, unsigned int ioctl,
88 unsigned long arg);
89 #ifdef CONFIG_COMPAT
90 static long kvm_vcpu_compat_ioctl(struct file *file, unsigned int ioctl,
91 unsigned long arg);
92 #endif
93 static int hardware_enable_all(void);
94 static void hardware_disable_all(void);
95
96 static void kvm_io_bus_destroy(struct kvm_io_bus *bus);
97
98 bool kvm_rebooting;
99 EXPORT_SYMBOL_GPL(kvm_rebooting);
100
101 static bool largepages_enabled = true;
102
103 bool kvm_is_mmio_pfn(pfn_t pfn)
104 {
105 if (pfn_valid(pfn)) {
106 int reserved;
107 struct page *tail = pfn_to_page(pfn);
108 struct page *head = compound_trans_head(tail);
109 reserved = PageReserved(head);
110 if (head != tail) {
111 /*
112 * "head" is not a dangling pointer
113 * (compound_trans_head takes care of that)
114 * but the hugepage may have been splitted
115 * from under us (and we may not hold a
116 * reference count on the head page so it can
117 * be reused before we run PageReferenced), so
118 * we've to check PageTail before returning
119 * what we just read.
120 */
121 smp_rmb();
122 if (PageTail(tail))
123 return reserved;
124 }
125 return PageReserved(tail);
126 }
127
128 return true;
129 }
130
131 /*
132 * Switches to specified vcpu, until a matching vcpu_put()
133 */
134 int vcpu_load(struct kvm_vcpu *vcpu)
135 {
136 int cpu;
137
138 if (mutex_lock_killable(&vcpu->mutex))
139 return -EINTR;
140 if (unlikely(vcpu->pid != current->pids[PIDTYPE_PID].pid)) {
141 /* The thread running this VCPU changed. */
142 struct pid *oldpid = vcpu->pid;
143 struct pid *newpid = get_task_pid(current, PIDTYPE_PID);
144 rcu_assign_pointer(vcpu->pid, newpid);
145 synchronize_rcu();
146 put_pid(oldpid);
147 }
148 cpu = get_cpu();
149 preempt_notifier_register(&vcpu->preempt_notifier);
150 kvm_arch_vcpu_load(vcpu, cpu);
151 put_cpu();
152 return 0;
153 }
154
155 void vcpu_put(struct kvm_vcpu *vcpu)
156 {
157 preempt_disable();
158 kvm_arch_vcpu_put(vcpu);
159 preempt_notifier_unregister(&vcpu->preempt_notifier);
160 preempt_enable();
161 mutex_unlock(&vcpu->mutex);
162 }
163
164 static void ack_flush(void *_completed)
165 {
166 }
167
168 static bool make_all_cpus_request(struct kvm *kvm, unsigned int req)
169 {
170 int i, cpu, me;
171 cpumask_var_t cpus;
172 bool called = true;
173 struct kvm_vcpu *vcpu;
174
175 zalloc_cpumask_var(&cpus, GFP_ATOMIC);
176
177 me = get_cpu();
178 kvm_for_each_vcpu(i, vcpu, kvm) {
179 kvm_make_request(req, vcpu);
180 cpu = vcpu->cpu;
181
182 /* Set ->requests bit before we read ->mode */
183 smp_mb();
184
185 if (cpus != NULL && cpu != -1 && cpu != me &&
186 kvm_vcpu_exiting_guest_mode(vcpu) != OUTSIDE_GUEST_MODE)
187 cpumask_set_cpu(cpu, cpus);
188 }
189 if (unlikely(cpus == NULL))
190 smp_call_function_many(cpu_online_mask, ack_flush, NULL, 1);
191 else if (!cpumask_empty(cpus))
192 smp_call_function_many(cpus, ack_flush, NULL, 1);
193 else
194 called = false;
195 put_cpu();
196 free_cpumask_var(cpus);
197 return called;
198 }
199
200 void kvm_flush_remote_tlbs(struct kvm *kvm)
201 {
202 long dirty_count = kvm->tlbs_dirty;
203
204 smp_mb();
205 if (make_all_cpus_request(kvm, KVM_REQ_TLB_FLUSH))
206 ++kvm->stat.remote_tlb_flush;
207 cmpxchg(&kvm->tlbs_dirty, dirty_count, 0);
208 }
209
210 void kvm_reload_remote_mmus(struct kvm *kvm)
211 {
212 make_all_cpus_request(kvm, KVM_REQ_MMU_RELOAD);
213 }
214
215 void kvm_make_mclock_inprogress_request(struct kvm *kvm)
216 {
217 make_all_cpus_request(kvm, KVM_REQ_MCLOCK_INPROGRESS);
218 }
219
220 void kvm_make_scan_ioapic_request(struct kvm *kvm)
221 {
222 make_all_cpus_request(kvm, KVM_REQ_SCAN_IOAPIC);
223 }
224
225 int kvm_vcpu_init(struct kvm_vcpu *vcpu, struct kvm *kvm, unsigned id)
226 {
227 struct page *page;
228 int r;
229
230 mutex_init(&vcpu->mutex);
231 vcpu->cpu = -1;
232 vcpu->kvm = kvm;
233 vcpu->vcpu_id = id;
234 vcpu->pid = NULL;
235 init_waitqueue_head(&vcpu->wq);
236 kvm_async_pf_vcpu_init(vcpu);
237
238 page = alloc_page(GFP_KERNEL | __GFP_ZERO);
239 if (!page) {
240 r = -ENOMEM;
241 goto fail;
242 }
243 vcpu->run = page_address(page);
244
245 kvm_vcpu_set_in_spin_loop(vcpu, false);
246 kvm_vcpu_set_dy_eligible(vcpu, false);
247 vcpu->preempted = false;
248
249 r = kvm_arch_vcpu_init(vcpu);
250 if (r < 0)
251 goto fail_free_run;
252 return 0;
253
254 fail_free_run:
255 free_page((unsigned long)vcpu->run);
256 fail:
257 return r;
258 }
259 EXPORT_SYMBOL_GPL(kvm_vcpu_init);
260
261 void kvm_vcpu_uninit(struct kvm_vcpu *vcpu)
262 {
263 put_pid(vcpu->pid);
264 kvm_arch_vcpu_uninit(vcpu);
265 free_page((unsigned long)vcpu->run);
266 }
267 EXPORT_SYMBOL_GPL(kvm_vcpu_uninit);
268
269 #if defined(CONFIG_MMU_NOTIFIER) && defined(KVM_ARCH_WANT_MMU_NOTIFIER)
270 static inline struct kvm *mmu_notifier_to_kvm(struct mmu_notifier *mn)
271 {
272 return container_of(mn, struct kvm, mmu_notifier);
273 }
274
275 static void kvm_mmu_notifier_invalidate_page(struct mmu_notifier *mn,
276 struct mm_struct *mm,
277 unsigned long address)
278 {
279 struct kvm *kvm = mmu_notifier_to_kvm(mn);
280 int need_tlb_flush, idx;
281
282 /*
283 * When ->invalidate_page runs, the linux pte has been zapped
284 * already but the page is still allocated until
285 * ->invalidate_page returns. So if we increase the sequence
286 * here the kvm page fault will notice if the spte can't be
287 * established because the page is going to be freed. If
288 * instead the kvm page fault establishes the spte before
289 * ->invalidate_page runs, kvm_unmap_hva will release it
290 * before returning.
291 *
292 * The sequence increase only need to be seen at spin_unlock
293 * time, and not at spin_lock time.
294 *
295 * Increasing the sequence after the spin_unlock would be
296 * unsafe because the kvm page fault could then establish the
297 * pte after kvm_unmap_hva returned, without noticing the page
298 * is going to be freed.
299 */
300 idx = srcu_read_lock(&kvm->srcu);
301 spin_lock(&kvm->mmu_lock);
302
303 kvm->mmu_notifier_seq++;
304 need_tlb_flush = kvm_unmap_hva(kvm, address) | kvm->tlbs_dirty;
305 /* we've to flush the tlb before the pages can be freed */
306 if (need_tlb_flush)
307 kvm_flush_remote_tlbs(kvm);
308
309 spin_unlock(&kvm->mmu_lock);
310 srcu_read_unlock(&kvm->srcu, idx);
311 }
312
313 static void kvm_mmu_notifier_change_pte(struct mmu_notifier *mn,
314 struct mm_struct *mm,
315 unsigned long address,
316 pte_t pte)
317 {
318 struct kvm *kvm = mmu_notifier_to_kvm(mn);
319 int idx;
320
321 idx = srcu_read_lock(&kvm->srcu);
322 spin_lock(&kvm->mmu_lock);
323 kvm->mmu_notifier_seq++;
324 kvm_set_spte_hva(kvm, address, pte);
325 spin_unlock(&kvm->mmu_lock);
326 srcu_read_unlock(&kvm->srcu, idx);
327 }
328
329 static void kvm_mmu_notifier_invalidate_range_start(struct mmu_notifier *mn,
330 struct mm_struct *mm,
331 unsigned long start,
332 unsigned long end)
333 {
334 struct kvm *kvm = mmu_notifier_to_kvm(mn);
335 int need_tlb_flush = 0, idx;
336
337 idx = srcu_read_lock(&kvm->srcu);
338 spin_lock(&kvm->mmu_lock);
339 /*
340 * The count increase must become visible at unlock time as no
341 * spte can be established without taking the mmu_lock and
342 * count is also read inside the mmu_lock critical section.
343 */
344 kvm->mmu_notifier_count++;
345 need_tlb_flush = kvm_unmap_hva_range(kvm, start, end);
346 need_tlb_flush |= kvm->tlbs_dirty;
347 /* we've to flush the tlb before the pages can be freed */
348 if (need_tlb_flush)
349 kvm_flush_remote_tlbs(kvm);
350
351 spin_unlock(&kvm->mmu_lock);
352 srcu_read_unlock(&kvm->srcu, idx);
353 }
354
355 static void kvm_mmu_notifier_invalidate_range_end(struct mmu_notifier *mn,
356 struct mm_struct *mm,
357 unsigned long start,
358 unsigned long end)
359 {
360 struct kvm *kvm = mmu_notifier_to_kvm(mn);
361
362 spin_lock(&kvm->mmu_lock);
363 /*
364 * This sequence increase will notify the kvm page fault that
365 * the page that is going to be mapped in the spte could have
366 * been freed.
367 */
368 kvm->mmu_notifier_seq++;
369 smp_wmb();
370 /*
371 * The above sequence increase must be visible before the
372 * below count decrease, which is ensured by the smp_wmb above
373 * in conjunction with the smp_rmb in mmu_notifier_retry().
374 */
375 kvm->mmu_notifier_count--;
376 spin_unlock(&kvm->mmu_lock);
377
378 BUG_ON(kvm->mmu_notifier_count < 0);
379 }
380
381 static int kvm_mmu_notifier_clear_flush_young(struct mmu_notifier *mn,
382 struct mm_struct *mm,
383 unsigned long address)
384 {
385 struct kvm *kvm = mmu_notifier_to_kvm(mn);
386 int young, idx;
387
388 idx = srcu_read_lock(&kvm->srcu);
389 spin_lock(&kvm->mmu_lock);
390
391 young = kvm_age_hva(kvm, address);
392 if (young)
393 kvm_flush_remote_tlbs(kvm);
394
395 spin_unlock(&kvm->mmu_lock);
396 srcu_read_unlock(&kvm->srcu, idx);
397
398 return young;
399 }
400
401 static int kvm_mmu_notifier_test_young(struct mmu_notifier *mn,
402 struct mm_struct *mm,
403 unsigned long address)
404 {
405 struct kvm *kvm = mmu_notifier_to_kvm(mn);
406 int young, idx;
407
408 idx = srcu_read_lock(&kvm->srcu);
409 spin_lock(&kvm->mmu_lock);
410 young = kvm_test_age_hva(kvm, address);
411 spin_unlock(&kvm->mmu_lock);
412 srcu_read_unlock(&kvm->srcu, idx);
413
414 return young;
415 }
416
417 static void kvm_mmu_notifier_release(struct mmu_notifier *mn,
418 struct mm_struct *mm)
419 {
420 struct kvm *kvm = mmu_notifier_to_kvm(mn);
421 int idx;
422
423 idx = srcu_read_lock(&kvm->srcu);
424 kvm_arch_flush_shadow_all(kvm);
425 srcu_read_unlock(&kvm->srcu, idx);
426 }
427
428 static const struct mmu_notifier_ops kvm_mmu_notifier_ops = {
429 .invalidate_page = kvm_mmu_notifier_invalidate_page,
430 .invalidate_range_start = kvm_mmu_notifier_invalidate_range_start,
431 .invalidate_range_end = kvm_mmu_notifier_invalidate_range_end,
432 .clear_flush_young = kvm_mmu_notifier_clear_flush_young,
433 .test_young = kvm_mmu_notifier_test_young,
434 .change_pte = kvm_mmu_notifier_change_pte,
435 .release = kvm_mmu_notifier_release,
436 };
437
438 static int kvm_init_mmu_notifier(struct kvm *kvm)
439 {
440 kvm->mmu_notifier.ops = &kvm_mmu_notifier_ops;
441 return mmu_notifier_register(&kvm->mmu_notifier, current->mm);
442 }
443
444 #else /* !(CONFIG_MMU_NOTIFIER && KVM_ARCH_WANT_MMU_NOTIFIER) */
445
446 static int kvm_init_mmu_notifier(struct kvm *kvm)
447 {
448 return 0;
449 }
450
451 #endif /* CONFIG_MMU_NOTIFIER && KVM_ARCH_WANT_MMU_NOTIFIER */
452
453 static void kvm_init_memslots_id(struct kvm *kvm)
454 {
455 int i;
456 struct kvm_memslots *slots = kvm->memslots;
457
458 for (i = 0; i < KVM_MEM_SLOTS_NUM; i++)
459 slots->id_to_index[i] = slots->memslots[i].id = i;
460 }
461
462 static struct kvm *kvm_create_vm(unsigned long type)
463 {
464 int r, i;
465 struct kvm *kvm = kvm_arch_alloc_vm();
466
467 if (!kvm)
468 return ERR_PTR(-ENOMEM);
469
470 r = kvm_arch_init_vm(kvm, type);
471 if (r)
472 goto out_err_nodisable;
473
474 r = hardware_enable_all();
475 if (r)
476 goto out_err_nodisable;
477
478 #ifdef CONFIG_HAVE_KVM_IRQCHIP
479 INIT_HLIST_HEAD(&kvm->mask_notifier_list);
480 INIT_HLIST_HEAD(&kvm->irq_ack_notifier_list);
481 #endif
482
483 BUILD_BUG_ON(KVM_MEM_SLOTS_NUM > SHRT_MAX);
484
485 r = -ENOMEM;
486 kvm->memslots = kzalloc(sizeof(struct kvm_memslots), GFP_KERNEL);
487 if (!kvm->memslots)
488 goto out_err_nosrcu;
489 kvm_init_memslots_id(kvm);
490 if (init_srcu_struct(&kvm->srcu))
491 goto out_err_nosrcu;
492 for (i = 0; i < KVM_NR_BUSES; i++) {
493 kvm->buses[i] = kzalloc(sizeof(struct kvm_io_bus),
494 GFP_KERNEL);
495 if (!kvm->buses[i])
496 goto out_err;
497 }
498
499 spin_lock_init(&kvm->mmu_lock);
500 kvm->mm = current->mm;
501 atomic_inc(&kvm->mm->mm_count);
502 kvm_eventfd_init(kvm);
503 mutex_init(&kvm->lock);
504 mutex_init(&kvm->irq_lock);
505 mutex_init(&kvm->slots_lock);
506 atomic_set(&kvm->users_count, 1);
507 INIT_LIST_HEAD(&kvm->devices);
508
509 r = kvm_init_mmu_notifier(kvm);
510 if (r)
511 goto out_err;
512
513 raw_spin_lock(&kvm_lock);
514 list_add(&kvm->vm_list, &vm_list);
515 raw_spin_unlock(&kvm_lock);
516
517 return kvm;
518
519 out_err:
520 cleanup_srcu_struct(&kvm->srcu);
521 out_err_nosrcu:
522 hardware_disable_all();
523 out_err_nodisable:
524 for (i = 0; i < KVM_NR_BUSES; i++)
525 kfree(kvm->buses[i]);
526 kfree(kvm->memslots);
527 kvm_arch_free_vm(kvm);
528 return ERR_PTR(r);
529 }
530
531 /*
532 * Avoid using vmalloc for a small buffer.
533 * Should not be used when the size is statically known.
534 */
535 void *kvm_kvzalloc(unsigned long size)
536 {
537 if (size > PAGE_SIZE)
538 return vzalloc(size);
539 else
540 return kzalloc(size, GFP_KERNEL);
541 }
542
543 void kvm_kvfree(const void *addr)
544 {
545 if (is_vmalloc_addr(addr))
546 vfree(addr);
547 else
548 kfree(addr);
549 }
550
551 static void kvm_destroy_dirty_bitmap(struct kvm_memory_slot *memslot)
552 {
553 if (!memslot->dirty_bitmap)
554 return;
555
556 kvm_kvfree(memslot->dirty_bitmap);
557 memslot->dirty_bitmap = NULL;
558 }
559
560 /*
561 * Free any memory in @free but not in @dont.
562 */
563 static void kvm_free_physmem_slot(struct kvm_memory_slot *free,
564 struct kvm_memory_slot *dont)
565 {
566 if (!dont || free->dirty_bitmap != dont->dirty_bitmap)
567 kvm_destroy_dirty_bitmap(free);
568
569 kvm_arch_free_memslot(free, dont);
570
571 free->npages = 0;
572 }
573
574 void kvm_free_physmem(struct kvm *kvm)
575 {
576 struct kvm_memslots *slots = kvm->memslots;
577 struct kvm_memory_slot *memslot;
578
579 kvm_for_each_memslot(memslot, slots)
580 kvm_free_physmem_slot(memslot, NULL);
581
582 kfree(kvm->memslots);
583 }
584
585 static void kvm_destroy_devices(struct kvm *kvm)
586 {
587 struct list_head *node, *tmp;
588
589 list_for_each_safe(node, tmp, &kvm->devices) {
590 struct kvm_device *dev =
591 list_entry(node, struct kvm_device, vm_node);
592
593 list_del(node);
594 dev->ops->destroy(dev);
595 }
596 }
597
598 static void kvm_destroy_vm(struct kvm *kvm)
599 {
600 int i;
601 struct mm_struct *mm = kvm->mm;
602
603 kvm_arch_sync_events(kvm);
604 raw_spin_lock(&kvm_lock);
605 list_del(&kvm->vm_list);
606 raw_spin_unlock(&kvm_lock);
607 kvm_free_irq_routing(kvm);
608 for (i = 0; i < KVM_NR_BUSES; i++)
609 kvm_io_bus_destroy(kvm->buses[i]);
610 kvm_coalesced_mmio_free(kvm);
611 #if defined(CONFIG_MMU_NOTIFIER) && defined(KVM_ARCH_WANT_MMU_NOTIFIER)
612 mmu_notifier_unregister(&kvm->mmu_notifier, kvm->mm);
613 #else
614 kvm_arch_flush_shadow_all(kvm);
615 #endif
616 kvm_arch_destroy_vm(kvm);
617 kvm_destroy_devices(kvm);
618 kvm_free_physmem(kvm);
619 cleanup_srcu_struct(&kvm->srcu);
620 kvm_arch_free_vm(kvm);
621 hardware_disable_all();
622 mmdrop(mm);
623 }
624
625 void kvm_get_kvm(struct kvm *kvm)
626 {
627 atomic_inc(&kvm->users_count);
628 }
629 EXPORT_SYMBOL_GPL(kvm_get_kvm);
630
631 void kvm_put_kvm(struct kvm *kvm)
632 {
633 if (atomic_dec_and_test(&kvm->users_count))
634 kvm_destroy_vm(kvm);
635 }
636 EXPORT_SYMBOL_GPL(kvm_put_kvm);
637
638
639 static int kvm_vm_release(struct inode *inode, struct file *filp)
640 {
641 struct kvm *kvm = filp->private_data;
642
643 kvm_irqfd_release(kvm);
644
645 kvm_put_kvm(kvm);
646 return 0;
647 }
648
649 /*
650 * Allocation size is twice as large as the actual dirty bitmap size.
651 * See x86's kvm_vm_ioctl_get_dirty_log() why this is needed.
652 */
653 static int kvm_create_dirty_bitmap(struct kvm_memory_slot *memslot)
654 {
655 #ifndef CONFIG_S390
656 unsigned long dirty_bytes = 2 * kvm_dirty_bitmap_bytes(memslot);
657
658 memslot->dirty_bitmap = kvm_kvzalloc(dirty_bytes);
659 if (!memslot->dirty_bitmap)
660 return -ENOMEM;
661
662 #endif /* !CONFIG_S390 */
663 return 0;
664 }
665
666 static int cmp_memslot(const void *slot1, const void *slot2)
667 {
668 struct kvm_memory_slot *s1, *s2;
669
670 s1 = (struct kvm_memory_slot *)slot1;
671 s2 = (struct kvm_memory_slot *)slot2;
672
673 if (s1->npages < s2->npages)
674 return 1;
675 if (s1->npages > s2->npages)
676 return -1;
677
678 return 0;
679 }
680
681 /*
682 * Sort the memslots base on its size, so the larger slots
683 * will get better fit.
684 */
685 static void sort_memslots(struct kvm_memslots *slots)
686 {
687 int i;
688
689 sort(slots->memslots, KVM_MEM_SLOTS_NUM,
690 sizeof(struct kvm_memory_slot), cmp_memslot, NULL);
691
692 for (i = 0; i < KVM_MEM_SLOTS_NUM; i++)
693 slots->id_to_index[slots->memslots[i].id] = i;
694 }
695
696 void update_memslots(struct kvm_memslots *slots, struct kvm_memory_slot *new,
697 u64 last_generation)
698 {
699 if (new) {
700 int id = new->id;
701 struct kvm_memory_slot *old = id_to_memslot(slots, id);
702 unsigned long npages = old->npages;
703
704 *old = *new;
705 if (new->npages != npages)
706 sort_memslots(slots);
707 }
708
709 slots->generation = last_generation + 1;
710 }
711
712 static int check_memory_region_flags(struct kvm_userspace_memory_region *mem)
713 {
714 u32 valid_flags = KVM_MEM_LOG_DIRTY_PAGES;
715
716 #ifdef KVM_CAP_READONLY_MEM
717 valid_flags |= KVM_MEM_READONLY;
718 #endif
719
720 if (mem->flags & ~valid_flags)
721 return -EINVAL;
722
723 return 0;
724 }
725
726 static struct kvm_memslots *install_new_memslots(struct kvm *kvm,
727 struct kvm_memslots *slots, struct kvm_memory_slot *new)
728 {
729 struct kvm_memslots *old_memslots = kvm->memslots;
730
731 update_memslots(slots, new, kvm->memslots->generation);
732 rcu_assign_pointer(kvm->memslots, slots);
733 synchronize_srcu_expedited(&kvm->srcu);
734 return old_memslots;
735 }
736
737 /*
738 * Allocate some memory and give it an address in the guest physical address
739 * space.
740 *
741 * Discontiguous memory is allowed, mostly for framebuffers.
742 *
743 * Must be called holding mmap_sem for write.
744 */
745 int __kvm_set_memory_region(struct kvm *kvm,
746 struct kvm_userspace_memory_region *mem)
747 {
748 int r;
749 gfn_t base_gfn;
750 unsigned long npages;
751 struct kvm_memory_slot *slot;
752 struct kvm_memory_slot old, new;
753 struct kvm_memslots *slots = NULL, *old_memslots;
754 enum kvm_mr_change change;
755
756 r = check_memory_region_flags(mem);
757 if (r)
758 goto out;
759
760 r = -EINVAL;
761 /* General sanity checks */
762 if (mem->memory_size & (PAGE_SIZE - 1))
763 goto out;
764 if (mem->guest_phys_addr & (PAGE_SIZE - 1))
765 goto out;
766 /* We can read the guest memory with __xxx_user() later on. */
767 if ((mem->slot < KVM_USER_MEM_SLOTS) &&
768 ((mem->userspace_addr & (PAGE_SIZE - 1)) ||
769 !access_ok(VERIFY_WRITE,
770 (void __user *)(unsigned long)mem->userspace_addr,
771 mem->memory_size)))
772 goto out;
773 if (mem->slot >= KVM_MEM_SLOTS_NUM)
774 goto out;
775 if (mem->guest_phys_addr + mem->memory_size < mem->guest_phys_addr)
776 goto out;
777
778 slot = id_to_memslot(kvm->memslots, mem->slot);
779 base_gfn = mem->guest_phys_addr >> PAGE_SHIFT;
780 npages = mem->memory_size >> PAGE_SHIFT;
781
782 r = -EINVAL;
783 if (npages > KVM_MEM_MAX_NR_PAGES)
784 goto out;
785
786 if (!npages)
787 mem->flags &= ~KVM_MEM_LOG_DIRTY_PAGES;
788
789 new = old = *slot;
790
791 new.id = mem->slot;
792 new.base_gfn = base_gfn;
793 new.npages = npages;
794 new.flags = mem->flags;
795
796 r = -EINVAL;
797 if (npages) {
798 if (!old.npages)
799 change = KVM_MR_CREATE;
800 else { /* Modify an existing slot. */
801 if ((mem->userspace_addr != old.userspace_addr) ||
802 (npages != old.npages) ||
803 ((new.flags ^ old.flags) & KVM_MEM_READONLY))
804 goto out;
805
806 if (base_gfn != old.base_gfn)
807 change = KVM_MR_MOVE;
808 else if (new.flags != old.flags)
809 change = KVM_MR_FLAGS_ONLY;
810 else { /* Nothing to change. */
811 r = 0;
812 goto out;
813 }
814 }
815 } else if (old.npages) {
816 change = KVM_MR_DELETE;
817 } else /* Modify a non-existent slot: disallowed. */
818 goto out;
819
820 if ((change == KVM_MR_CREATE) || (change == KVM_MR_MOVE)) {
821 /* Check for overlaps */
822 r = -EEXIST;
823 kvm_for_each_memslot(slot, kvm->memslots) {
824 if ((slot->id >= KVM_USER_MEM_SLOTS) ||
825 (slot->id == mem->slot))
826 continue;
827 if (!((base_gfn + npages <= slot->base_gfn) ||
828 (base_gfn >= slot->base_gfn + slot->npages)))
829 goto out;
830 }
831 }
832
833 /* Free page dirty bitmap if unneeded */
834 if (!(new.flags & KVM_MEM_LOG_DIRTY_PAGES))
835 new.dirty_bitmap = NULL;
836
837 r = -ENOMEM;
838 if (change == KVM_MR_CREATE) {
839 new.userspace_addr = mem->userspace_addr;
840
841 if (kvm_arch_create_memslot(&new, npages))
842 goto out_free;
843 }
844
845 /* Allocate page dirty bitmap if needed */
846 if ((new.flags & KVM_MEM_LOG_DIRTY_PAGES) && !new.dirty_bitmap) {
847 if (kvm_create_dirty_bitmap(&new) < 0)
848 goto out_free;
849 }
850
851 if ((change == KVM_MR_DELETE) || (change == KVM_MR_MOVE)) {
852 r = -ENOMEM;
853 slots = kmemdup(kvm->memslots, sizeof(struct kvm_memslots),
854 GFP_KERNEL);
855 if (!slots)
856 goto out_free;
857 slot = id_to_memslot(slots, mem->slot);
858 slot->flags |= KVM_MEMSLOT_INVALID;
859
860 old_memslots = install_new_memslots(kvm, slots, NULL);
861
862 /* slot was deleted or moved, clear iommu mapping */
863 kvm_iommu_unmap_pages(kvm, &old);
864 /* From this point no new shadow pages pointing to a deleted,
865 * or moved, memslot will be created.
866 *
867 * validation of sp->gfn happens in:
868 * - gfn_to_hva (kvm_read_guest, gfn_to_pfn)
869 * - kvm_is_visible_gfn (mmu_check_roots)
870 */
871 kvm_arch_flush_shadow_memslot(kvm, slot);
872 slots = old_memslots;
873 }
874
875 r = kvm_arch_prepare_memory_region(kvm, &new, mem, change);
876 if (r)
877 goto out_slots;
878
879 r = -ENOMEM;
880 /*
881 * We can re-use the old_memslots from above, the only difference
882 * from the currently installed memslots is the invalid flag. This
883 * will get overwritten by update_memslots anyway.
884 */
885 if (!slots) {
886 slots = kmemdup(kvm->memslots, sizeof(struct kvm_memslots),
887 GFP_KERNEL);
888 if (!slots)
889 goto out_free;
890 }
891
892 /*
893 * IOMMU mapping: New slots need to be mapped. Old slots need to be
894 * un-mapped and re-mapped if their base changes. Since base change
895 * unmapping is handled above with slot deletion, mapping alone is
896 * needed here. Anything else the iommu might care about for existing
897 * slots (size changes, userspace addr changes and read-only flag
898 * changes) is disallowed above, so any other attribute changes getting
899 * here can be skipped.
900 */
901 if ((change == KVM_MR_CREATE) || (change == KVM_MR_MOVE)) {
902 r = kvm_iommu_map_pages(kvm, &new);
903 if (r)
904 goto out_slots;
905 }
906
907 /* actual memory is freed via old in kvm_free_physmem_slot below */
908 if (change == KVM_MR_DELETE) {
909 new.dirty_bitmap = NULL;
910 memset(&new.arch, 0, sizeof(new.arch));
911 }
912
913 old_memslots = install_new_memslots(kvm, slots, &new);
914
915 kvm_arch_commit_memory_region(kvm, mem, &old, change);
916
917 kvm_free_physmem_slot(&old, &new);
918 kfree(old_memslots);
919
920 return 0;
921
922 out_slots:
923 kfree(slots);
924 out_free:
925 kvm_free_physmem_slot(&new, &old);
926 out:
927 return r;
928 }
929 EXPORT_SYMBOL_GPL(__kvm_set_memory_region);
930
931 int kvm_set_memory_region(struct kvm *kvm,
932 struct kvm_userspace_memory_region *mem)
933 {
934 int r;
935
936 mutex_lock(&kvm->slots_lock);
937 r = __kvm_set_memory_region(kvm, mem);
938 mutex_unlock(&kvm->slots_lock);
939 return r;
940 }
941 EXPORT_SYMBOL_GPL(kvm_set_memory_region);
942
943 int kvm_vm_ioctl_set_memory_region(struct kvm *kvm,
944 struct kvm_userspace_memory_region *mem)
945 {
946 if (mem->slot >= KVM_USER_MEM_SLOTS)
947 return -EINVAL;
948 return kvm_set_memory_region(kvm, mem);
949 }
950
951 int kvm_get_dirty_log(struct kvm *kvm,
952 struct kvm_dirty_log *log, int *is_dirty)
953 {
954 struct kvm_memory_slot *memslot;
955 int r, i;
956 unsigned long n;
957 unsigned long any = 0;
958
959 r = -EINVAL;
960 if (log->slot >= KVM_USER_MEM_SLOTS)
961 goto out;
962
963 memslot = id_to_memslot(kvm->memslots, log->slot);
964 r = -ENOENT;
965 if (!memslot->dirty_bitmap)
966 goto out;
967
968 n = kvm_dirty_bitmap_bytes(memslot);
969
970 for (i = 0; !any && i < n/sizeof(long); ++i)
971 any = memslot->dirty_bitmap[i];
972
973 r = -EFAULT;
974 if (copy_to_user(log->dirty_bitmap, memslot->dirty_bitmap, n))
975 goto out;
976
977 if (any)
978 *is_dirty = 1;
979
980 r = 0;
981 out:
982 return r;
983 }
984
985 bool kvm_largepages_enabled(void)
986 {
987 return largepages_enabled;
988 }
989
990 void kvm_disable_largepages(void)
991 {
992 largepages_enabled = false;
993 }
994 EXPORT_SYMBOL_GPL(kvm_disable_largepages);
995
996 struct kvm_memory_slot *gfn_to_memslot(struct kvm *kvm, gfn_t gfn)
997 {
998 return __gfn_to_memslot(kvm_memslots(kvm), gfn);
999 }
1000 EXPORT_SYMBOL_GPL(gfn_to_memslot);
1001
1002 int kvm_is_visible_gfn(struct kvm *kvm, gfn_t gfn)
1003 {
1004 struct kvm_memory_slot *memslot = gfn_to_memslot(kvm, gfn);
1005
1006 if (!memslot || memslot->id >= KVM_USER_MEM_SLOTS ||
1007 memslot->flags & KVM_MEMSLOT_INVALID)
1008 return 0;
1009
1010 return 1;
1011 }
1012 EXPORT_SYMBOL_GPL(kvm_is_visible_gfn);
1013
1014 unsigned long kvm_host_page_size(struct kvm *kvm, gfn_t gfn)
1015 {
1016 struct vm_area_struct *vma;
1017 unsigned long addr, size;
1018
1019 size = PAGE_SIZE;
1020
1021 addr = gfn_to_hva(kvm, gfn);
1022 if (kvm_is_error_hva(addr))
1023 return PAGE_SIZE;
1024
1025 down_read(&current->mm->mmap_sem);
1026 vma = find_vma(current->mm, addr);
1027 if (!vma)
1028 goto out;
1029
1030 size = vma_kernel_pagesize(vma);
1031
1032 out:
1033 up_read(&current->mm->mmap_sem);
1034
1035 return size;
1036 }
1037
1038 static bool memslot_is_readonly(struct kvm_memory_slot *slot)
1039 {
1040 return slot->flags & KVM_MEM_READONLY;
1041 }
1042
1043 static unsigned long __gfn_to_hva_many(struct kvm_memory_slot *slot, gfn_t gfn,
1044 gfn_t *nr_pages, bool write)
1045 {
1046 if (!slot || slot->flags & KVM_MEMSLOT_INVALID)
1047 return KVM_HVA_ERR_BAD;
1048
1049 if (memslot_is_readonly(slot) && write)
1050 return KVM_HVA_ERR_RO_BAD;
1051
1052 if (nr_pages)
1053 *nr_pages = slot->npages - (gfn - slot->base_gfn);
1054
1055 return __gfn_to_hva_memslot(slot, gfn);
1056 }
1057
1058 static unsigned long gfn_to_hva_many(struct kvm_memory_slot *slot, gfn_t gfn,
1059 gfn_t *nr_pages)
1060 {
1061 return __gfn_to_hva_many(slot, gfn, nr_pages, true);
1062 }
1063
1064 unsigned long gfn_to_hva_memslot(struct kvm_memory_slot *slot,
1065 gfn_t gfn)
1066 {
1067 return gfn_to_hva_many(slot, gfn, NULL);
1068 }
1069 EXPORT_SYMBOL_GPL(gfn_to_hva_memslot);
1070
1071 unsigned long gfn_to_hva(struct kvm *kvm, gfn_t gfn)
1072 {
1073 return gfn_to_hva_many(gfn_to_memslot(kvm, gfn), gfn, NULL);
1074 }
1075 EXPORT_SYMBOL_GPL(gfn_to_hva);
1076
1077 /*
1078 * The hva returned by this function is only allowed to be read.
1079 * It should pair with kvm_read_hva() or kvm_read_hva_atomic().
1080 */
1081 static unsigned long gfn_to_hva_read(struct kvm *kvm, gfn_t gfn)
1082 {
1083 return __gfn_to_hva_many(gfn_to_memslot(kvm, gfn), gfn, NULL, false);
1084 }
1085
1086 static int kvm_read_hva(void *data, void __user *hva, int len)
1087 {
1088 return __copy_from_user(data, hva, len);
1089 }
1090
1091 static int kvm_read_hva_atomic(void *data, void __user *hva, int len)
1092 {
1093 return __copy_from_user_inatomic(data, hva, len);
1094 }
1095
1096 static int get_user_page_nowait(struct task_struct *tsk, struct mm_struct *mm,
1097 unsigned long start, int write, struct page **page)
1098 {
1099 int flags = FOLL_TOUCH | FOLL_NOWAIT | FOLL_HWPOISON | FOLL_GET;
1100
1101 if (write)
1102 flags |= FOLL_WRITE;
1103
1104 return __get_user_pages(tsk, mm, start, 1, flags, page, NULL, NULL);
1105 }
1106
1107 static inline int check_user_page_hwpoison(unsigned long addr)
1108 {
1109 int rc, flags = FOLL_TOUCH | FOLL_HWPOISON | FOLL_WRITE;
1110
1111 rc = __get_user_pages(current, current->mm, addr, 1,
1112 flags, NULL, NULL, NULL);
1113 return rc == -EHWPOISON;
1114 }
1115
1116 /*
1117 * The atomic path to get the writable pfn which will be stored in @pfn,
1118 * true indicates success, otherwise false is returned.
1119 */
1120 static bool hva_to_pfn_fast(unsigned long addr, bool atomic, bool *async,
1121 bool write_fault, bool *writable, pfn_t *pfn)
1122 {
1123 struct page *page[1];
1124 int npages;
1125
1126 if (!(async || atomic))
1127 return false;
1128
1129 /*
1130 * Fast pin a writable pfn only if it is a write fault request
1131 * or the caller allows to map a writable pfn for a read fault
1132 * request.
1133 */
1134 if (!(write_fault || writable))
1135 return false;
1136
1137 npages = __get_user_pages_fast(addr, 1, 1, page);
1138 if (npages == 1) {
1139 *pfn = page_to_pfn(page[0]);
1140
1141 if (writable)
1142 *writable = true;
1143 return true;
1144 }
1145
1146 return false;
1147 }
1148
1149 /*
1150 * The slow path to get the pfn of the specified host virtual address,
1151 * 1 indicates success, -errno is returned if error is detected.
1152 */
1153 static int hva_to_pfn_slow(unsigned long addr, bool *async, bool write_fault,
1154 bool *writable, pfn_t *pfn)
1155 {
1156 struct page *page[1];
1157 int npages = 0;
1158
1159 might_sleep();
1160
1161 if (writable)
1162 *writable = write_fault;
1163
1164 if (async) {
1165 down_read(&current->mm->mmap_sem);
1166 npages = get_user_page_nowait(current, current->mm,
1167 addr, write_fault, page);
1168 up_read(&current->mm->mmap_sem);
1169 } else
1170 npages = get_user_pages_fast(addr, 1, write_fault,
1171 page);
1172 if (npages != 1)
1173 return npages;
1174
1175 /* map read fault as writable if possible */
1176 if (unlikely(!write_fault) && writable) {
1177 struct page *wpage[1];
1178
1179 npages = __get_user_pages_fast(addr, 1, 1, wpage);
1180 if (npages == 1) {
1181 *writable = true;
1182 put_page(page[0]);
1183 page[0] = wpage[0];
1184 }
1185
1186 npages = 1;
1187 }
1188 *pfn = page_to_pfn(page[0]);
1189 return npages;
1190 }
1191
1192 static bool vma_is_valid(struct vm_area_struct *vma, bool write_fault)
1193 {
1194 if (unlikely(!(vma->vm_flags & VM_READ)))
1195 return false;
1196
1197 if (write_fault && (unlikely(!(vma->vm_flags & VM_WRITE))))
1198 return false;
1199
1200 return true;
1201 }
1202
1203 /*
1204 * Pin guest page in memory and return its pfn.
1205 * @addr: host virtual address which maps memory to the guest
1206 * @atomic: whether this function can sleep
1207 * @async: whether this function need to wait IO complete if the
1208 * host page is not in the memory
1209 * @write_fault: whether we should get a writable host page
1210 * @writable: whether it allows to map a writable host page for !@write_fault
1211 *
1212 * The function will map a writable host page for these two cases:
1213 * 1): @write_fault = true
1214 * 2): @write_fault = false && @writable, @writable will tell the caller
1215 * whether the mapping is writable.
1216 */
1217 static pfn_t hva_to_pfn(unsigned long addr, bool atomic, bool *async,
1218 bool write_fault, bool *writable)
1219 {
1220 struct vm_area_struct *vma;
1221 pfn_t pfn = 0;
1222 int npages;
1223
1224 /* we can do it either atomically or asynchronously, not both */
1225 BUG_ON(atomic && async);
1226
1227 if (hva_to_pfn_fast(addr, atomic, async, write_fault, writable, &pfn))
1228 return pfn;
1229
1230 if (atomic)
1231 return KVM_PFN_ERR_FAULT;
1232
1233 npages = hva_to_pfn_slow(addr, async, write_fault, writable, &pfn);
1234 if (npages == 1)
1235 return pfn;
1236
1237 down_read(&current->mm->mmap_sem);
1238 if (npages == -EHWPOISON ||
1239 (!async && check_user_page_hwpoison(addr))) {
1240 pfn = KVM_PFN_ERR_HWPOISON;
1241 goto exit;
1242 }
1243
1244 vma = find_vma_intersection(current->mm, addr, addr + 1);
1245
1246 if (vma == NULL)
1247 pfn = KVM_PFN_ERR_FAULT;
1248 else if ((vma->vm_flags & VM_PFNMAP)) {
1249 pfn = ((addr - vma->vm_start) >> PAGE_SHIFT) +
1250 vma->vm_pgoff;
1251 BUG_ON(!kvm_is_mmio_pfn(pfn));
1252 } else {
1253 if (async && vma_is_valid(vma, write_fault))
1254 *async = true;
1255 pfn = KVM_PFN_ERR_FAULT;
1256 }
1257 exit:
1258 up_read(&current->mm->mmap_sem);
1259 return pfn;
1260 }
1261
1262 static pfn_t
1263 __gfn_to_pfn_memslot(struct kvm_memory_slot *slot, gfn_t gfn, bool atomic,
1264 bool *async, bool write_fault, bool *writable)
1265 {
1266 unsigned long addr = __gfn_to_hva_many(slot, gfn, NULL, write_fault);
1267
1268 if (addr == KVM_HVA_ERR_RO_BAD)
1269 return KVM_PFN_ERR_RO_FAULT;
1270
1271 if (kvm_is_error_hva(addr))
1272 return KVM_PFN_NOSLOT;
1273
1274 /* Do not map writable pfn in the readonly memslot. */
1275 if (writable && memslot_is_readonly(slot)) {
1276 *writable = false;
1277 writable = NULL;
1278 }
1279
1280 return hva_to_pfn(addr, atomic, async, write_fault,
1281 writable);
1282 }
1283
1284 static pfn_t __gfn_to_pfn(struct kvm *kvm, gfn_t gfn, bool atomic, bool *async,
1285 bool write_fault, bool *writable)
1286 {
1287 struct kvm_memory_slot *slot;
1288
1289 if (async)
1290 *async = false;
1291
1292 slot = gfn_to_memslot(kvm, gfn);
1293
1294 return __gfn_to_pfn_memslot(slot, gfn, atomic, async, write_fault,
1295 writable);
1296 }
1297
1298 pfn_t gfn_to_pfn_atomic(struct kvm *kvm, gfn_t gfn)
1299 {
1300 return __gfn_to_pfn(kvm, gfn, true, NULL, true, NULL);
1301 }
1302 EXPORT_SYMBOL_GPL(gfn_to_pfn_atomic);
1303
1304 pfn_t gfn_to_pfn_async(struct kvm *kvm, gfn_t gfn, bool *async,
1305 bool write_fault, bool *writable)
1306 {
1307 return __gfn_to_pfn(kvm, gfn, false, async, write_fault, writable);
1308 }
1309 EXPORT_SYMBOL_GPL(gfn_to_pfn_async);
1310
1311 pfn_t gfn_to_pfn(struct kvm *kvm, gfn_t gfn)
1312 {
1313 return __gfn_to_pfn(kvm, gfn, false, NULL, true, NULL);
1314 }
1315 EXPORT_SYMBOL_GPL(gfn_to_pfn);
1316
1317 pfn_t gfn_to_pfn_prot(struct kvm *kvm, gfn_t gfn, bool write_fault,
1318 bool *writable)
1319 {
1320 return __gfn_to_pfn(kvm, gfn, false, NULL, write_fault, writable);
1321 }
1322 EXPORT_SYMBOL_GPL(gfn_to_pfn_prot);
1323
1324 pfn_t gfn_to_pfn_memslot(struct kvm_memory_slot *slot, gfn_t gfn)
1325 {
1326 return __gfn_to_pfn_memslot(slot, gfn, false, NULL, true, NULL);
1327 }
1328
1329 pfn_t gfn_to_pfn_memslot_atomic(struct kvm_memory_slot *slot, gfn_t gfn)
1330 {
1331 return __gfn_to_pfn_memslot(slot, gfn, true, NULL, true, NULL);
1332 }
1333 EXPORT_SYMBOL_GPL(gfn_to_pfn_memslot_atomic);
1334
1335 int gfn_to_page_many_atomic(struct kvm *kvm, gfn_t gfn, struct page **pages,
1336 int nr_pages)
1337 {
1338 unsigned long addr;
1339 gfn_t entry;
1340
1341 addr = gfn_to_hva_many(gfn_to_memslot(kvm, gfn), gfn, &entry);
1342 if (kvm_is_error_hva(addr))
1343 return -1;
1344
1345 if (entry < nr_pages)
1346 return 0;
1347
1348 return __get_user_pages_fast(addr, nr_pages, 1, pages);
1349 }
1350 EXPORT_SYMBOL_GPL(gfn_to_page_many_atomic);
1351
1352 static struct page *kvm_pfn_to_page(pfn_t pfn)
1353 {
1354 if (is_error_noslot_pfn(pfn))
1355 return KVM_ERR_PTR_BAD_PAGE;
1356
1357 if (kvm_is_mmio_pfn(pfn)) {
1358 WARN_ON(1);
1359 return KVM_ERR_PTR_BAD_PAGE;
1360 }
1361
1362 return pfn_to_page(pfn);
1363 }
1364
1365 struct page *gfn_to_page(struct kvm *kvm, gfn_t gfn)
1366 {
1367 pfn_t pfn;
1368
1369 pfn = gfn_to_pfn(kvm, gfn);
1370
1371 return kvm_pfn_to_page(pfn);
1372 }
1373
1374 EXPORT_SYMBOL_GPL(gfn_to_page);
1375
1376 void kvm_release_page_clean(struct page *page)
1377 {
1378 WARN_ON(is_error_page(page));
1379
1380 kvm_release_pfn_clean(page_to_pfn(page));
1381 }
1382 EXPORT_SYMBOL_GPL(kvm_release_page_clean);
1383
1384 void kvm_release_pfn_clean(pfn_t pfn)
1385 {
1386 if (!is_error_noslot_pfn(pfn) && !kvm_is_mmio_pfn(pfn))
1387 put_page(pfn_to_page(pfn));
1388 }
1389 EXPORT_SYMBOL_GPL(kvm_release_pfn_clean);
1390
1391 void kvm_release_page_dirty(struct page *page)
1392 {
1393 WARN_ON(is_error_page(page));
1394
1395 kvm_release_pfn_dirty(page_to_pfn(page));
1396 }
1397 EXPORT_SYMBOL_GPL(kvm_release_page_dirty);
1398
1399 void kvm_release_pfn_dirty(pfn_t pfn)
1400 {
1401 kvm_set_pfn_dirty(pfn);
1402 kvm_release_pfn_clean(pfn);
1403 }
1404 EXPORT_SYMBOL_GPL(kvm_release_pfn_dirty);
1405
1406 void kvm_set_page_dirty(struct page *page)
1407 {
1408 kvm_set_pfn_dirty(page_to_pfn(page));
1409 }
1410 EXPORT_SYMBOL_GPL(kvm_set_page_dirty);
1411
1412 void kvm_set_pfn_dirty(pfn_t pfn)
1413 {
1414 if (!kvm_is_mmio_pfn(pfn)) {
1415 struct page *page = pfn_to_page(pfn);
1416 if (!PageReserved(page))
1417 SetPageDirty(page);
1418 }
1419 }
1420 EXPORT_SYMBOL_GPL(kvm_set_pfn_dirty);
1421
1422 void kvm_set_pfn_accessed(pfn_t pfn)
1423 {
1424 if (!kvm_is_mmio_pfn(pfn))
1425 mark_page_accessed(pfn_to_page(pfn));
1426 }
1427 EXPORT_SYMBOL_GPL(kvm_set_pfn_accessed);
1428
1429 void kvm_get_pfn(pfn_t pfn)
1430 {
1431 if (!kvm_is_mmio_pfn(pfn))
1432 get_page(pfn_to_page(pfn));
1433 }
1434 EXPORT_SYMBOL_GPL(kvm_get_pfn);
1435
1436 static int next_segment(unsigned long len, int offset)
1437 {
1438 if (len > PAGE_SIZE - offset)
1439 return PAGE_SIZE - offset;
1440 else
1441 return len;
1442 }
1443
1444 int kvm_read_guest_page(struct kvm *kvm, gfn_t gfn, void *data, int offset,
1445 int len)
1446 {
1447 int r;
1448 unsigned long addr;
1449
1450 addr = gfn_to_hva_read(kvm, gfn);
1451 if (kvm_is_error_hva(addr))
1452 return -EFAULT;
1453 r = kvm_read_hva(data, (void __user *)addr + offset, len);
1454 if (r)
1455 return -EFAULT;
1456 return 0;
1457 }
1458 EXPORT_SYMBOL_GPL(kvm_read_guest_page);
1459
1460 int kvm_read_guest(struct kvm *kvm, gpa_t gpa, void *data, unsigned long len)
1461 {
1462 gfn_t gfn = gpa >> PAGE_SHIFT;
1463 int seg;
1464 int offset = offset_in_page(gpa);
1465 int ret;
1466
1467 while ((seg = next_segment(len, offset)) != 0) {
1468 ret = kvm_read_guest_page(kvm, gfn, data, offset, seg);
1469 if (ret < 0)
1470 return ret;
1471 offset = 0;
1472 len -= seg;
1473 data += seg;
1474 ++gfn;
1475 }
1476 return 0;
1477 }
1478 EXPORT_SYMBOL_GPL(kvm_read_guest);
1479
1480 int kvm_read_guest_atomic(struct kvm *kvm, gpa_t gpa, void *data,
1481 unsigned long len)
1482 {
1483 int r;
1484 unsigned long addr;
1485 gfn_t gfn = gpa >> PAGE_SHIFT;
1486 int offset = offset_in_page(gpa);
1487
1488 addr = gfn_to_hva_read(kvm, gfn);
1489 if (kvm_is_error_hva(addr))
1490 return -EFAULT;
1491 pagefault_disable();
1492 r = kvm_read_hva_atomic(data, (void __user *)addr + offset, len);
1493 pagefault_enable();
1494 if (r)
1495 return -EFAULT;
1496 return 0;
1497 }
1498 EXPORT_SYMBOL(kvm_read_guest_atomic);
1499
1500 int kvm_write_guest_page(struct kvm *kvm, gfn_t gfn, const void *data,
1501 int offset, int len)
1502 {
1503 int r;
1504 unsigned long addr;
1505
1506 addr = gfn_to_hva(kvm, gfn);
1507 if (kvm_is_error_hva(addr))
1508 return -EFAULT;
1509 r = __copy_to_user((void __user *)addr + offset, data, len);
1510 if (r)
1511 return -EFAULT;
1512 mark_page_dirty(kvm, gfn);
1513 return 0;
1514 }
1515 EXPORT_SYMBOL_GPL(kvm_write_guest_page);
1516
1517 int kvm_write_guest(struct kvm *kvm, gpa_t gpa, const void *data,
1518 unsigned long len)
1519 {
1520 gfn_t gfn = gpa >> PAGE_SHIFT;
1521 int seg;
1522 int offset = offset_in_page(gpa);
1523 int ret;
1524
1525 while ((seg = next_segment(len, offset)) != 0) {
1526 ret = kvm_write_guest_page(kvm, gfn, data, offset, seg);
1527 if (ret < 0)
1528 return ret;
1529 offset = 0;
1530 len -= seg;
1531 data += seg;
1532 ++gfn;
1533 }
1534 return 0;
1535 }
1536
1537 int kvm_gfn_to_hva_cache_init(struct kvm *kvm, struct gfn_to_hva_cache *ghc,
1538 gpa_t gpa, unsigned long len)
1539 {
1540 struct kvm_memslots *slots = kvm_memslots(kvm);
1541 int offset = offset_in_page(gpa);
1542 gfn_t start_gfn = gpa >> PAGE_SHIFT;
1543 gfn_t end_gfn = (gpa + len - 1) >> PAGE_SHIFT;
1544 gfn_t nr_pages_needed = end_gfn - start_gfn + 1;
1545 gfn_t nr_pages_avail;
1546
1547 ghc->gpa = gpa;
1548 ghc->generation = slots->generation;
1549 ghc->len = len;
1550 ghc->memslot = gfn_to_memslot(kvm, start_gfn);
1551 ghc->hva = gfn_to_hva_many(ghc->memslot, start_gfn, &nr_pages_avail);
1552 if (!kvm_is_error_hva(ghc->hva) && nr_pages_avail >= nr_pages_needed) {
1553 ghc->hva += offset;
1554 } else {
1555 /*
1556 * If the requested region crosses two memslots, we still
1557 * verify that the entire region is valid here.
1558 */
1559 while (start_gfn <= end_gfn) {
1560 ghc->memslot = gfn_to_memslot(kvm, start_gfn);
1561 ghc->hva = gfn_to_hva_many(ghc->memslot, start_gfn,
1562 &nr_pages_avail);
1563 if (kvm_is_error_hva(ghc->hva))
1564 return -EFAULT;
1565 start_gfn += nr_pages_avail;
1566 }
1567 /* Use the slow path for cross page reads and writes. */
1568 ghc->memslot = NULL;
1569 }
1570 return 0;
1571 }
1572 EXPORT_SYMBOL_GPL(kvm_gfn_to_hva_cache_init);
1573
1574 int kvm_write_guest_cached(struct kvm *kvm, struct gfn_to_hva_cache *ghc,
1575 void *data, unsigned long len)
1576 {
1577 struct kvm_memslots *slots = kvm_memslots(kvm);
1578 int r;
1579
1580 BUG_ON(len > ghc->len);
1581
1582 if (slots->generation != ghc->generation)
1583 kvm_gfn_to_hva_cache_init(kvm, ghc, ghc->gpa, ghc->len);
1584
1585 if (unlikely(!ghc->memslot))
1586 return kvm_write_guest(kvm, ghc->gpa, data, len);
1587
1588 if (kvm_is_error_hva(ghc->hva))
1589 return -EFAULT;
1590
1591 r = __copy_to_user((void __user *)ghc->hva, data, len);
1592 if (r)
1593 return -EFAULT;
1594 mark_page_dirty_in_slot(kvm, ghc->memslot, ghc->gpa >> PAGE_SHIFT);
1595
1596 return 0;
1597 }
1598 EXPORT_SYMBOL_GPL(kvm_write_guest_cached);
1599
1600 int kvm_read_guest_cached(struct kvm *kvm, struct gfn_to_hva_cache *ghc,
1601 void *data, unsigned long len)
1602 {
1603 struct kvm_memslots *slots = kvm_memslots(kvm);
1604 int r;
1605
1606 BUG_ON(len > ghc->len);
1607
1608 if (slots->generation != ghc->generation)
1609 kvm_gfn_to_hva_cache_init(kvm, ghc, ghc->gpa, ghc->len);
1610
1611 if (unlikely(!ghc->memslot))
1612 return kvm_read_guest(kvm, ghc->gpa, data, len);
1613
1614 if (kvm_is_error_hva(ghc->hva))
1615 return -EFAULT;
1616
1617 r = __copy_from_user(data, (void __user *)ghc->hva, len);
1618 if (r)
1619 return -EFAULT;
1620
1621 return 0;
1622 }
1623 EXPORT_SYMBOL_GPL(kvm_read_guest_cached);
1624
1625 int kvm_clear_guest_page(struct kvm *kvm, gfn_t gfn, int offset, int len)
1626 {
1627 return kvm_write_guest_page(kvm, gfn, (const void *) empty_zero_page,
1628 offset, len);
1629 }
1630 EXPORT_SYMBOL_GPL(kvm_clear_guest_page);
1631
1632 int kvm_clear_guest(struct kvm *kvm, gpa_t gpa, unsigned long len)
1633 {
1634 gfn_t gfn = gpa >> PAGE_SHIFT;
1635 int seg;
1636 int offset = offset_in_page(gpa);
1637 int ret;
1638
1639 while ((seg = next_segment(len, offset)) != 0) {
1640 ret = kvm_clear_guest_page(kvm, gfn, offset, seg);
1641 if (ret < 0)
1642 return ret;
1643 offset = 0;
1644 len -= seg;
1645 ++gfn;
1646 }
1647 return 0;
1648 }
1649 EXPORT_SYMBOL_GPL(kvm_clear_guest);
1650
1651 void mark_page_dirty_in_slot(struct kvm *kvm, struct kvm_memory_slot *memslot,
1652 gfn_t gfn)
1653 {
1654 if (memslot && memslot->dirty_bitmap) {
1655 unsigned long rel_gfn = gfn - memslot->base_gfn;
1656
1657 set_bit_le(rel_gfn, memslot->dirty_bitmap);
1658 }
1659 }
1660
1661 void mark_page_dirty(struct kvm *kvm, gfn_t gfn)
1662 {
1663 struct kvm_memory_slot *memslot;
1664
1665 memslot = gfn_to_memslot(kvm, gfn);
1666 mark_page_dirty_in_slot(kvm, memslot, gfn);
1667 }
1668
1669 /*
1670 * The vCPU has executed a HLT instruction with in-kernel mode enabled.
1671 */
1672 void kvm_vcpu_block(struct kvm_vcpu *vcpu)
1673 {
1674 DEFINE_WAIT(wait);
1675
1676 for (;;) {
1677 prepare_to_wait(&vcpu->wq, &wait, TASK_INTERRUPTIBLE);
1678
1679 if (kvm_arch_vcpu_runnable(vcpu)) {
1680 kvm_make_request(KVM_REQ_UNHALT, vcpu);
1681 break;
1682 }
1683 if (kvm_cpu_has_pending_timer(vcpu))
1684 break;
1685 if (signal_pending(current))
1686 break;
1687
1688 schedule();
1689 }
1690
1691 finish_wait(&vcpu->wq, &wait);
1692 }
1693
1694 #ifndef CONFIG_S390
1695 /*
1696 * Kick a sleeping VCPU, or a guest VCPU in guest mode, into host kernel mode.
1697 */
1698 void kvm_vcpu_kick(struct kvm_vcpu *vcpu)
1699 {
1700 int me;
1701 int cpu = vcpu->cpu;
1702 wait_queue_head_t *wqp;
1703
1704 wqp = kvm_arch_vcpu_wq(vcpu);
1705 if (waitqueue_active(wqp)) {
1706 wake_up_interruptible(wqp);
1707 ++vcpu->stat.halt_wakeup;
1708 }
1709
1710 me = get_cpu();
1711 if (cpu != me && (unsigned)cpu < nr_cpu_ids && cpu_online(cpu))
1712 if (kvm_arch_vcpu_should_kick(vcpu))
1713 smp_send_reschedule(cpu);
1714 put_cpu();
1715 }
1716 EXPORT_SYMBOL_GPL(kvm_vcpu_kick);
1717 #endif /* !CONFIG_S390 */
1718
1719 void kvm_resched(struct kvm_vcpu *vcpu)
1720 {
1721 if (!need_resched())
1722 return;
1723 cond_resched();
1724 }
1725 EXPORT_SYMBOL_GPL(kvm_resched);
1726
1727 bool kvm_vcpu_yield_to(struct kvm_vcpu *target)
1728 {
1729 struct pid *pid;
1730 struct task_struct *task = NULL;
1731 bool ret = false;
1732
1733 rcu_read_lock();
1734 pid = rcu_dereference(target->pid);
1735 if (pid)
1736 task = get_pid_task(target->pid, PIDTYPE_PID);
1737 rcu_read_unlock();
1738 if (!task)
1739 return ret;
1740 if (task->flags & PF_VCPU) {
1741 put_task_struct(task);
1742 return ret;
1743 }
1744 ret = yield_to(task, 1);
1745 put_task_struct(task);
1746
1747 return ret;
1748 }
1749 EXPORT_SYMBOL_GPL(kvm_vcpu_yield_to);
1750
1751 #ifdef CONFIG_HAVE_KVM_CPU_RELAX_INTERCEPT
1752 /*
1753 * Helper that checks whether a VCPU is eligible for directed yield.
1754 * Most eligible candidate to yield is decided by following heuristics:
1755 *
1756 * (a) VCPU which has not done pl-exit or cpu relax intercepted recently
1757 * (preempted lock holder), indicated by @in_spin_loop.
1758 * Set at the beiginning and cleared at the end of interception/PLE handler.
1759 *
1760 * (b) VCPU which has done pl-exit/ cpu relax intercepted but did not get
1761 * chance last time (mostly it has become eligible now since we have probably
1762 * yielded to lockholder in last iteration. This is done by toggling
1763 * @dy_eligible each time a VCPU checked for eligibility.)
1764 *
1765 * Yielding to a recently pl-exited/cpu relax intercepted VCPU before yielding
1766 * to preempted lock-holder could result in wrong VCPU selection and CPU
1767 * burning. Giving priority for a potential lock-holder increases lock
1768 * progress.
1769 *
1770 * Since algorithm is based on heuristics, accessing another VCPU data without
1771 * locking does not harm. It may result in trying to yield to same VCPU, fail
1772 * and continue with next VCPU and so on.
1773 */
1774 bool kvm_vcpu_eligible_for_directed_yield(struct kvm_vcpu *vcpu)
1775 {
1776 bool eligible;
1777
1778 eligible = !vcpu->spin_loop.in_spin_loop ||
1779 (vcpu->spin_loop.in_spin_loop &&
1780 vcpu->spin_loop.dy_eligible);
1781
1782 if (vcpu->spin_loop.in_spin_loop)
1783 kvm_vcpu_set_dy_eligible(vcpu, !vcpu->spin_loop.dy_eligible);
1784
1785 return eligible;
1786 }
1787 #endif
1788
1789 void kvm_vcpu_on_spin(struct kvm_vcpu *me)
1790 {
1791 struct kvm *kvm = me->kvm;
1792 struct kvm_vcpu *vcpu;
1793 int last_boosted_vcpu = me->kvm->last_boosted_vcpu;
1794 int yielded = 0;
1795 int try = 3;
1796 int pass;
1797 int i;
1798
1799 kvm_vcpu_set_in_spin_loop(me, true);
1800 /*
1801 * We boost the priority of a VCPU that is runnable but not
1802 * currently running, because it got preempted by something
1803 * else and called schedule in __vcpu_run. Hopefully that
1804 * VCPU is holding the lock that we need and will release it.
1805 * We approximate round-robin by starting at the last boosted VCPU.
1806 */
1807 for (pass = 0; pass < 2 && !yielded && try; pass++) {
1808 kvm_for_each_vcpu(i, vcpu, kvm) {
1809 if (!pass && i <= last_boosted_vcpu) {
1810 i = last_boosted_vcpu;
1811 continue;
1812 } else if (pass && i > last_boosted_vcpu)
1813 break;
1814 if (!ACCESS_ONCE(vcpu->preempted))
1815 continue;
1816 if (vcpu == me)
1817 continue;
1818 if (waitqueue_active(&vcpu->wq))
1819 continue;
1820 if (!kvm_vcpu_eligible_for_directed_yield(vcpu))
1821 continue;
1822
1823 yielded = kvm_vcpu_yield_to(vcpu);
1824 if (yielded > 0) {
1825 kvm->last_boosted_vcpu = i;
1826 break;
1827 } else if (yielded < 0) {
1828 try--;
1829 if (!try)
1830 break;
1831 }
1832 }
1833 }
1834 kvm_vcpu_set_in_spin_loop(me, false);
1835
1836 /* Ensure vcpu is not eligible during next spinloop */
1837 kvm_vcpu_set_dy_eligible(me, false);
1838 }
1839 EXPORT_SYMBOL_GPL(kvm_vcpu_on_spin);
1840
1841 static int kvm_vcpu_fault(struct vm_area_struct *vma, struct vm_fault *vmf)
1842 {
1843 struct kvm_vcpu *vcpu = vma->vm_file->private_data;
1844 struct page *page;
1845
1846 if (vmf->pgoff == 0)
1847 page = virt_to_page(vcpu->run);
1848 #ifdef CONFIG_X86
1849 else if (vmf->pgoff == KVM_PIO_PAGE_OFFSET)
1850 page = virt_to_page(vcpu->arch.pio_data);
1851 #endif
1852 #ifdef KVM_COALESCED_MMIO_PAGE_OFFSET
1853 else if (vmf->pgoff == KVM_COALESCED_MMIO_PAGE_OFFSET)
1854 page = virt_to_page(vcpu->kvm->coalesced_mmio_ring);
1855 #endif
1856 else
1857 return kvm_arch_vcpu_fault(vcpu, vmf);
1858 get_page(page);
1859 vmf->page = page;
1860 return 0;
1861 }
1862
1863 static const struct vm_operations_struct kvm_vcpu_vm_ops = {
1864 .fault = kvm_vcpu_fault,
1865 };
1866
1867 static int kvm_vcpu_mmap(struct file *file, struct vm_area_struct *vma)
1868 {
1869 vma->vm_ops = &kvm_vcpu_vm_ops;
1870 return 0;
1871 }
1872
1873 static int kvm_vcpu_release(struct inode *inode, struct file *filp)
1874 {
1875 struct kvm_vcpu *vcpu = filp->private_data;
1876
1877 kvm_put_kvm(vcpu->kvm);
1878 return 0;
1879 }
1880
1881 static struct file_operations kvm_vcpu_fops = {
1882 .release = kvm_vcpu_release,
1883 .unlocked_ioctl = kvm_vcpu_ioctl,
1884 #ifdef CONFIG_COMPAT
1885 .compat_ioctl = kvm_vcpu_compat_ioctl,
1886 #endif
1887 .mmap = kvm_vcpu_mmap,
1888 .llseek = noop_llseek,
1889 };
1890
1891 /*
1892 * Allocates an inode for the vcpu.
1893 */
1894 static int create_vcpu_fd(struct kvm_vcpu *vcpu)
1895 {
1896 return anon_inode_getfd("kvm-vcpu", &kvm_vcpu_fops, vcpu, O_RDWR);
1897 }
1898
1899 /*
1900 * Creates some virtual cpus. Good luck creating more than one.
1901 */
1902 static int kvm_vm_ioctl_create_vcpu(struct kvm *kvm, u32 id)
1903 {
1904 int r;
1905 struct kvm_vcpu *vcpu, *v;
1906
1907 vcpu = kvm_arch_vcpu_create(kvm, id);
1908 if (IS_ERR(vcpu))
1909 return PTR_ERR(vcpu);
1910
1911 preempt_notifier_init(&vcpu->preempt_notifier, &kvm_preempt_ops);
1912
1913 r = kvm_arch_vcpu_setup(vcpu);
1914 if (r)
1915 goto vcpu_destroy;
1916
1917 mutex_lock(&kvm->lock);
1918 if (!kvm_vcpu_compatible(vcpu)) {
1919 r = -EINVAL;
1920 goto unlock_vcpu_destroy;
1921 }
1922 if (atomic_read(&kvm->online_vcpus) == KVM_MAX_VCPUS) {
1923 r = -EINVAL;
1924 goto unlock_vcpu_destroy;
1925 }
1926
1927 kvm_for_each_vcpu(r, v, kvm)
1928 if (v->vcpu_id == id) {
1929 r = -EEXIST;
1930 goto unlock_vcpu_destroy;
1931 }
1932
1933 BUG_ON(kvm->vcpus[atomic_read(&kvm->online_vcpus)]);
1934
1935 /* Now it's all set up, let userspace reach it */
1936 kvm_get_kvm(kvm);
1937 r = create_vcpu_fd(vcpu);
1938 if (r < 0) {
1939 kvm_put_kvm(kvm);
1940 goto unlock_vcpu_destroy;
1941 }
1942
1943 kvm->vcpus[atomic_read(&kvm->online_vcpus)] = vcpu;
1944 smp_wmb();
1945 atomic_inc(&kvm->online_vcpus);
1946
1947 mutex_unlock(&kvm->lock);
1948 kvm_arch_vcpu_postcreate(vcpu);
1949 return r;
1950
1951 unlock_vcpu_destroy:
1952 mutex_unlock(&kvm->lock);
1953 vcpu_destroy:
1954 kvm_arch_vcpu_destroy(vcpu);
1955 return r;
1956 }
1957
1958 static int kvm_vcpu_ioctl_set_sigmask(struct kvm_vcpu *vcpu, sigset_t *sigset)
1959 {
1960 if (sigset) {
1961 sigdelsetmask(sigset, sigmask(SIGKILL)|sigmask(SIGSTOP));
1962 vcpu->sigset_active = 1;
1963 vcpu->sigset = *sigset;
1964 } else
1965 vcpu->sigset_active = 0;
1966 return 0;
1967 }
1968
1969 static long kvm_vcpu_ioctl(struct file *filp,
1970 unsigned int ioctl, unsigned long arg)
1971 {
1972 struct kvm_vcpu *vcpu = filp->private_data;
1973 void __user *argp = (void __user *)arg;
1974 int r;
1975 struct kvm_fpu *fpu = NULL;
1976 struct kvm_sregs *kvm_sregs = NULL;
1977
1978 if (vcpu->kvm->mm != current->mm)
1979 return -EIO;
1980
1981 #if defined(CONFIG_S390) || defined(CONFIG_PPC) || defined(CONFIG_MIPS)
1982 /*
1983 * Special cases: vcpu ioctls that are asynchronous to vcpu execution,
1984 * so vcpu_load() would break it.
1985 */
1986 if (ioctl == KVM_S390_INTERRUPT || ioctl == KVM_INTERRUPT)
1987 return kvm_arch_vcpu_ioctl(filp, ioctl, arg);
1988 #endif
1989
1990
1991 r = vcpu_load(vcpu);
1992 if (r)
1993 return r;
1994 switch (ioctl) {
1995 case KVM_RUN:
1996 r = -EINVAL;
1997 if (arg)
1998 goto out;
1999 r = kvm_arch_vcpu_ioctl_run(vcpu, vcpu->run);
2000 trace_kvm_userspace_exit(vcpu->run->exit_reason, r);
2001 break;
2002 case KVM_GET_REGS: {
2003 struct kvm_regs *kvm_regs;
2004
2005 r = -ENOMEM;
2006 kvm_regs = kzalloc(sizeof(struct kvm_regs), GFP_KERNEL);
2007 if (!kvm_regs)
2008 goto out;
2009 r = kvm_arch_vcpu_ioctl_get_regs(vcpu, kvm_regs);
2010 if (r)
2011 goto out_free1;
2012 r = -EFAULT;
2013 if (copy_to_user(argp, kvm_regs, sizeof(struct kvm_regs)))
2014 goto out_free1;
2015 r = 0;
2016 out_free1:
2017 kfree(kvm_regs);
2018 break;
2019 }
2020 case KVM_SET_REGS: {
2021 struct kvm_regs *kvm_regs;
2022
2023 r = -ENOMEM;
2024 kvm_regs = memdup_user(argp, sizeof(*kvm_regs));
2025 if (IS_ERR(kvm_regs)) {
2026 r = PTR_ERR(kvm_regs);
2027 goto out;
2028 }
2029 r = kvm_arch_vcpu_ioctl_set_regs(vcpu, kvm_regs);
2030 kfree(kvm_regs);
2031 break;
2032 }
2033 case KVM_GET_SREGS: {
2034 kvm_sregs = kzalloc(sizeof(struct kvm_sregs), GFP_KERNEL);
2035 r = -ENOMEM;
2036 if (!kvm_sregs)
2037 goto out;
2038 r = kvm_arch_vcpu_ioctl_get_sregs(vcpu, kvm_sregs);
2039 if (r)
2040 goto out;
2041 r = -EFAULT;
2042 if (copy_to_user(argp, kvm_sregs, sizeof(struct kvm_sregs)))
2043 goto out;
2044 r = 0;
2045 break;
2046 }
2047 case KVM_SET_SREGS: {
2048 kvm_sregs = memdup_user(argp, sizeof(*kvm_sregs));
2049 if (IS_ERR(kvm_sregs)) {
2050 r = PTR_ERR(kvm_sregs);
2051 kvm_sregs = NULL;
2052 goto out;
2053 }
2054 r = kvm_arch_vcpu_ioctl_set_sregs(vcpu, kvm_sregs);
2055 break;
2056 }
2057 case KVM_GET_MP_STATE: {
2058 struct kvm_mp_state mp_state;
2059
2060 r = kvm_arch_vcpu_ioctl_get_mpstate(vcpu, &mp_state);
2061 if (r)
2062 goto out;
2063 r = -EFAULT;
2064 if (copy_to_user(argp, &mp_state, sizeof mp_state))
2065 goto out;
2066 r = 0;
2067 break;
2068 }
2069 case KVM_SET_MP_STATE: {
2070 struct kvm_mp_state mp_state;
2071
2072 r = -EFAULT;
2073 if (copy_from_user(&mp_state, argp, sizeof mp_state))
2074 goto out;
2075 r = kvm_arch_vcpu_ioctl_set_mpstate(vcpu, &mp_state);
2076 break;
2077 }
2078 case KVM_TRANSLATE: {
2079 struct kvm_translation tr;
2080
2081 r = -EFAULT;
2082 if (copy_from_user(&tr, argp, sizeof tr))
2083 goto out;
2084 r = kvm_arch_vcpu_ioctl_translate(vcpu, &tr);
2085 if (r)
2086 goto out;
2087 r = -EFAULT;
2088 if (copy_to_user(argp, &tr, sizeof tr))
2089 goto out;
2090 r = 0;
2091 break;
2092 }
2093 case KVM_SET_GUEST_DEBUG: {
2094 struct kvm_guest_debug dbg;
2095
2096 r = -EFAULT;
2097 if (copy_from_user(&dbg, argp, sizeof dbg))
2098 goto out;
2099 r = kvm_arch_vcpu_ioctl_set_guest_debug(vcpu, &dbg);
2100 break;
2101 }
2102 case KVM_SET_SIGNAL_MASK: {
2103 struct kvm_signal_mask __user *sigmask_arg = argp;
2104 struct kvm_signal_mask kvm_sigmask;
2105 sigset_t sigset, *p;
2106
2107 p = NULL;
2108 if (argp) {
2109 r = -EFAULT;
2110 if (copy_from_user(&kvm_sigmask, argp,
2111 sizeof kvm_sigmask))
2112 goto out;
2113 r = -EINVAL;
2114 if (kvm_sigmask.len != sizeof sigset)
2115 goto out;
2116 r = -EFAULT;
2117 if (copy_from_user(&sigset, sigmask_arg->sigset,
2118 sizeof sigset))
2119 goto out;
2120 p = &sigset;
2121 }
2122 r = kvm_vcpu_ioctl_set_sigmask(vcpu, p);
2123 break;
2124 }
2125 case KVM_GET_FPU: {
2126 fpu = kzalloc(sizeof(struct kvm_fpu), GFP_KERNEL);
2127 r = -ENOMEM;
2128 if (!fpu)
2129 goto out;
2130 r = kvm_arch_vcpu_ioctl_get_fpu(vcpu, fpu);
2131 if (r)
2132 goto out;
2133 r = -EFAULT;
2134 if (copy_to_user(argp, fpu, sizeof(struct kvm_fpu)))
2135 goto out;
2136 r = 0;
2137 break;
2138 }
2139 case KVM_SET_FPU: {
2140 fpu = memdup_user(argp, sizeof(*fpu));
2141 if (IS_ERR(fpu)) {
2142 r = PTR_ERR(fpu);
2143 fpu = NULL;
2144 goto out;
2145 }
2146 r = kvm_arch_vcpu_ioctl_set_fpu(vcpu, fpu);
2147 break;
2148 }
2149 default:
2150 r = kvm_arch_vcpu_ioctl(filp, ioctl, arg);
2151 }
2152 out:
2153 vcpu_put(vcpu);
2154 kfree(fpu);
2155 kfree(kvm_sregs);
2156 return r;
2157 }
2158
2159 #ifdef CONFIG_COMPAT
2160 static long kvm_vcpu_compat_ioctl(struct file *filp,
2161 unsigned int ioctl, unsigned long arg)
2162 {
2163 struct kvm_vcpu *vcpu = filp->private_data;
2164 void __user *argp = compat_ptr(arg);
2165 int r;
2166
2167 if (vcpu->kvm->mm != current->mm)
2168 return -EIO;
2169
2170 switch (ioctl) {
2171 case KVM_SET_SIGNAL_MASK: {
2172 struct kvm_signal_mask __user *sigmask_arg = argp;
2173 struct kvm_signal_mask kvm_sigmask;
2174 compat_sigset_t csigset;
2175 sigset_t sigset;
2176
2177 if (argp) {
2178 r = -EFAULT;
2179 if (copy_from_user(&kvm_sigmask, argp,
2180 sizeof kvm_sigmask))
2181 goto out;
2182 r = -EINVAL;
2183 if (kvm_sigmask.len != sizeof csigset)
2184 goto out;
2185 r = -EFAULT;
2186 if (copy_from_user(&csigset, sigmask_arg->sigset,
2187 sizeof csigset))
2188 goto out;
2189 sigset_from_compat(&sigset, &csigset);
2190 r = kvm_vcpu_ioctl_set_sigmask(vcpu, &sigset);
2191 } else
2192 r = kvm_vcpu_ioctl_set_sigmask(vcpu, NULL);
2193 break;
2194 }
2195 default:
2196 r = kvm_vcpu_ioctl(filp, ioctl, arg);
2197 }
2198
2199 out:
2200 return r;
2201 }
2202 #endif
2203
2204 static int kvm_device_ioctl_attr(struct kvm_device *dev,
2205 int (*accessor)(struct kvm_device *dev,
2206 struct kvm_device_attr *attr),
2207 unsigned long arg)
2208 {
2209 struct kvm_device_attr attr;
2210
2211 if (!accessor)
2212 return -EPERM;
2213
2214 if (copy_from_user(&attr, (void __user *)arg, sizeof(attr)))
2215 return -EFAULT;
2216
2217 return accessor(dev, &attr);
2218 }
2219
2220 static long kvm_device_ioctl(struct file *filp, unsigned int ioctl,
2221 unsigned long arg)
2222 {
2223 struct kvm_device *dev = filp->private_data;
2224
2225 switch (ioctl) {
2226 case KVM_SET_DEVICE_ATTR:
2227 return kvm_device_ioctl_attr(dev, dev->ops->set_attr, arg);
2228 case KVM_GET_DEVICE_ATTR:
2229 return kvm_device_ioctl_attr(dev, dev->ops->get_attr, arg);
2230 case KVM_HAS_DEVICE_ATTR:
2231 return kvm_device_ioctl_attr(dev, dev->ops->has_attr, arg);
2232 default:
2233 if (dev->ops->ioctl)
2234 return dev->ops->ioctl(dev, ioctl, arg);
2235
2236 return -ENOTTY;
2237 }
2238 }
2239
2240 static int kvm_device_release(struct inode *inode, struct file *filp)
2241 {
2242 struct kvm_device *dev = filp->private_data;
2243 struct kvm *kvm = dev->kvm;
2244
2245 kvm_put_kvm(kvm);
2246 return 0;
2247 }
2248
2249 static const struct file_operations kvm_device_fops = {
2250 .unlocked_ioctl = kvm_device_ioctl,
2251 #ifdef CONFIG_COMPAT
2252 .compat_ioctl = kvm_device_ioctl,
2253 #endif
2254 .release = kvm_device_release,
2255 };
2256
2257 struct kvm_device *kvm_device_from_filp(struct file *filp)
2258 {
2259 if (filp->f_op != &kvm_device_fops)
2260 return NULL;
2261
2262 return filp->private_data;
2263 }
2264
2265 static int kvm_ioctl_create_device(struct kvm *kvm,
2266 struct kvm_create_device *cd)
2267 {
2268 struct kvm_device_ops *ops = NULL;
2269 struct kvm_device *dev;
2270 bool test = cd->flags & KVM_CREATE_DEVICE_TEST;
2271 int ret;
2272
2273 switch (cd->type) {
2274 #ifdef CONFIG_KVM_MPIC
2275 case KVM_DEV_TYPE_FSL_MPIC_20:
2276 case KVM_DEV_TYPE_FSL_MPIC_42:
2277 ops = &kvm_mpic_ops;
2278 break;
2279 #endif
2280 #ifdef CONFIG_KVM_XICS
2281 case KVM_DEV_TYPE_XICS:
2282 ops = &kvm_xics_ops;
2283 break;
2284 #endif
2285 default:
2286 return -ENODEV;
2287 }
2288
2289 if (test)
2290 return 0;
2291
2292 dev = kzalloc(sizeof(*dev), GFP_KERNEL);
2293 if (!dev)
2294 return -ENOMEM;
2295
2296 dev->ops = ops;
2297 dev->kvm = kvm;
2298
2299 ret = ops->create(dev, cd->type);
2300 if (ret < 0) {
2301 kfree(dev);
2302 return ret;
2303 }
2304
2305 ret = anon_inode_getfd(ops->name, &kvm_device_fops, dev, O_RDWR);
2306 if (ret < 0) {
2307 ops->destroy(dev);
2308 return ret;
2309 }
2310
2311 list_add(&dev->vm_node, &kvm->devices);
2312 kvm_get_kvm(kvm);
2313 cd->fd = ret;
2314 return 0;
2315 }
2316
2317 static long kvm_vm_ioctl(struct file *filp,
2318 unsigned int ioctl, unsigned long arg)
2319 {
2320 struct kvm *kvm = filp->private_data;
2321 void __user *argp = (void __user *)arg;
2322 int r;
2323
2324 if (kvm->mm != current->mm)
2325 return -EIO;
2326 switch (ioctl) {
2327 case KVM_CREATE_VCPU:
2328 r = kvm_vm_ioctl_create_vcpu(kvm, arg);
2329 break;
2330 case KVM_SET_USER_MEMORY_REGION: {
2331 struct kvm_userspace_memory_region kvm_userspace_mem;
2332
2333 r = -EFAULT;
2334 if (copy_from_user(&kvm_userspace_mem, argp,
2335 sizeof kvm_userspace_mem))
2336 goto out;
2337
2338 r = kvm_vm_ioctl_set_memory_region(kvm, &kvm_userspace_mem);
2339 break;
2340 }
2341 case KVM_GET_DIRTY_LOG: {
2342 struct kvm_dirty_log log;
2343
2344 r = -EFAULT;
2345 if (copy_from_user(&log, argp, sizeof log))
2346 goto out;
2347 r = kvm_vm_ioctl_get_dirty_log(kvm, &log);
2348 break;
2349 }
2350 #ifdef KVM_COALESCED_MMIO_PAGE_OFFSET
2351 case KVM_REGISTER_COALESCED_MMIO: {
2352 struct kvm_coalesced_mmio_zone zone;
2353 r = -EFAULT;
2354 if (copy_from_user(&zone, argp, sizeof zone))
2355 goto out;
2356 r = kvm_vm_ioctl_register_coalesced_mmio(kvm, &zone);
2357 break;
2358 }
2359 case KVM_UNREGISTER_COALESCED_MMIO: {
2360 struct kvm_coalesced_mmio_zone zone;
2361 r = -EFAULT;
2362 if (copy_from_user(&zone, argp, sizeof zone))
2363 goto out;
2364 r = kvm_vm_ioctl_unregister_coalesced_mmio(kvm, &zone);
2365 break;
2366 }
2367 #endif
2368 case KVM_IRQFD: {
2369 struct kvm_irqfd data;
2370
2371 r = -EFAULT;
2372 if (copy_from_user(&data, argp, sizeof data))
2373 goto out;
2374 r = kvm_irqfd(kvm, &data);
2375 break;
2376 }
2377 case KVM_IOEVENTFD: {
2378 struct kvm_ioeventfd data;
2379
2380 r = -EFAULT;
2381 if (copy_from_user(&data, argp, sizeof data))
2382 goto out;
2383 r = kvm_ioeventfd(kvm, &data);
2384 break;
2385 }
2386 #ifdef CONFIG_KVM_APIC_ARCHITECTURE
2387 case KVM_SET_BOOT_CPU_ID:
2388 r = 0;
2389 mutex_lock(&kvm->lock);
2390 if (atomic_read(&kvm->online_vcpus) != 0)
2391 r = -EBUSY;
2392 else
2393 kvm->bsp_vcpu_id = arg;
2394 mutex_unlock(&kvm->lock);
2395 break;
2396 #endif
2397 #ifdef CONFIG_HAVE_KVM_MSI
2398 case KVM_SIGNAL_MSI: {
2399 struct kvm_msi msi;
2400
2401 r = -EFAULT;
2402 if (copy_from_user(&msi, argp, sizeof msi))
2403 goto out;
2404 r = kvm_send_userspace_msi(kvm, &msi);
2405 break;
2406 }
2407 #endif
2408 #ifdef __KVM_HAVE_IRQ_LINE
2409 case KVM_IRQ_LINE_STATUS:
2410 case KVM_IRQ_LINE: {
2411 struct kvm_irq_level irq_event;
2412
2413 r = -EFAULT;
2414 if (copy_from_user(&irq_event, argp, sizeof irq_event))
2415 goto out;
2416
2417 r = kvm_vm_ioctl_irq_line(kvm, &irq_event,
2418 ioctl == KVM_IRQ_LINE_STATUS);
2419 if (r)
2420 goto out;
2421
2422 r = -EFAULT;
2423 if (ioctl == KVM_IRQ_LINE_STATUS) {
2424 if (copy_to_user(argp, &irq_event, sizeof irq_event))
2425 goto out;
2426 }
2427
2428 r = 0;
2429 break;
2430 }
2431 #endif
2432 #ifdef CONFIG_HAVE_KVM_IRQ_ROUTING
2433 case KVM_SET_GSI_ROUTING: {
2434 struct kvm_irq_routing routing;
2435 struct kvm_irq_routing __user *urouting;
2436 struct kvm_irq_routing_entry *entries;
2437
2438 r = -EFAULT;
2439 if (copy_from_user(&routing, argp, sizeof(routing)))
2440 goto out;
2441 r = -EINVAL;
2442 if (routing.nr >= KVM_MAX_IRQ_ROUTES)
2443 goto out;
2444 if (routing.flags)
2445 goto out;
2446 r = -ENOMEM;
2447 entries = vmalloc(routing.nr * sizeof(*entries));
2448 if (!entries)
2449 goto out;
2450 r = -EFAULT;
2451 urouting = argp;
2452 if (copy_from_user(entries, urouting->entries,
2453 routing.nr * sizeof(*entries)))
2454 goto out_free_irq_routing;
2455 r = kvm_set_irq_routing(kvm, entries, routing.nr,
2456 routing.flags);
2457 out_free_irq_routing:
2458 vfree(entries);
2459 break;
2460 }
2461 #endif /* CONFIG_HAVE_KVM_IRQ_ROUTING */
2462 case KVM_CREATE_DEVICE: {
2463 struct kvm_create_device cd;
2464
2465 r = -EFAULT;
2466 if (copy_from_user(&cd, argp, sizeof(cd)))
2467 goto out;
2468
2469 r = kvm_ioctl_create_device(kvm, &cd);
2470 if (r)
2471 goto out;
2472
2473 r = -EFAULT;
2474 if (copy_to_user(argp, &cd, sizeof(cd)))
2475 goto out;
2476
2477 r = 0;
2478 break;
2479 }
2480 default:
2481 r = kvm_arch_vm_ioctl(filp, ioctl, arg);
2482 if (r == -ENOTTY)
2483 r = kvm_vm_ioctl_assigned_device(kvm, ioctl, arg);
2484 }
2485 out:
2486 return r;
2487 }
2488
2489 #ifdef CONFIG_COMPAT
2490 struct compat_kvm_dirty_log {
2491 __u32 slot;
2492 __u32 padding1;
2493 union {
2494 compat_uptr_t dirty_bitmap; /* one bit per page */
2495 __u64 padding2;
2496 };
2497 };
2498
2499 static long kvm_vm_compat_ioctl(struct file *filp,
2500 unsigned int ioctl, unsigned long arg)
2501 {
2502 struct kvm *kvm = filp->private_data;
2503 int r;
2504
2505 if (kvm->mm != current->mm)
2506 return -EIO;
2507 switch (ioctl) {
2508 case KVM_GET_DIRTY_LOG: {
2509 struct compat_kvm_dirty_log compat_log;
2510 struct kvm_dirty_log log;
2511
2512 r = -EFAULT;
2513 if (copy_from_user(&compat_log, (void __user *)arg,
2514 sizeof(compat_log)))
2515 goto out;
2516 log.slot = compat_log.slot;
2517 log.padding1 = compat_log.padding1;
2518 log.padding2 = compat_log.padding2;
2519 log.dirty_bitmap = compat_ptr(compat_log.dirty_bitmap);
2520
2521 r = kvm_vm_ioctl_get_dirty_log(kvm, &log);
2522 break;
2523 }
2524 default:
2525 r = kvm_vm_ioctl(filp, ioctl, arg);
2526 }
2527
2528 out:
2529 return r;
2530 }
2531 #endif
2532
2533 static int kvm_vm_fault(struct vm_area_struct *vma, struct vm_fault *vmf)
2534 {
2535 struct page *page[1];
2536 unsigned long addr;
2537 int npages;
2538 gfn_t gfn = vmf->pgoff;
2539 struct kvm *kvm = vma->vm_file->private_data;
2540
2541 addr = gfn_to_hva(kvm, gfn);
2542 if (kvm_is_error_hva(addr))
2543 return VM_FAULT_SIGBUS;
2544
2545 npages = get_user_pages(current, current->mm, addr, 1, 1, 0, page,
2546 NULL);
2547 if (unlikely(npages != 1))
2548 return VM_FAULT_SIGBUS;
2549
2550 vmf->page = page[0];
2551 return 0;
2552 }
2553
2554 static const struct vm_operations_struct kvm_vm_vm_ops = {
2555 .fault = kvm_vm_fault,
2556 };
2557
2558 static int kvm_vm_mmap(struct file *file, struct vm_area_struct *vma)
2559 {
2560 vma->vm_ops = &kvm_vm_vm_ops;
2561 return 0;
2562 }
2563
2564 static struct file_operations kvm_vm_fops = {
2565 .release = kvm_vm_release,
2566 .unlocked_ioctl = kvm_vm_ioctl,
2567 #ifdef CONFIG_COMPAT
2568 .compat_ioctl = kvm_vm_compat_ioctl,
2569 #endif
2570 .mmap = kvm_vm_mmap,
2571 .llseek = noop_llseek,
2572 };
2573
2574 static int kvm_dev_ioctl_create_vm(unsigned long type)
2575 {
2576 int r;
2577 struct kvm *kvm;
2578
2579 kvm = kvm_create_vm(type);
2580 if (IS_ERR(kvm))
2581 return PTR_ERR(kvm);
2582 #ifdef KVM_COALESCED_MMIO_PAGE_OFFSET
2583 r = kvm_coalesced_mmio_init(kvm);
2584 if (r < 0) {
2585 kvm_put_kvm(kvm);
2586 return r;
2587 }
2588 #endif
2589 r = anon_inode_getfd("kvm-vm", &kvm_vm_fops, kvm, O_RDWR);
2590 if (r < 0)
2591 kvm_put_kvm(kvm);
2592
2593 return r;
2594 }
2595
2596 static long kvm_dev_ioctl_check_extension_generic(long arg)
2597 {
2598 switch (arg) {
2599 case KVM_CAP_USER_MEMORY:
2600 case KVM_CAP_DESTROY_MEMORY_REGION_WORKS:
2601 case KVM_CAP_JOIN_MEMORY_REGIONS_WORKS:
2602 #ifdef CONFIG_KVM_APIC_ARCHITECTURE
2603 case KVM_CAP_SET_BOOT_CPU_ID:
2604 #endif
2605 case KVM_CAP_INTERNAL_ERROR_DATA:
2606 #ifdef CONFIG_HAVE_KVM_MSI
2607 case KVM_CAP_SIGNAL_MSI:
2608 #endif
2609 #ifdef CONFIG_HAVE_KVM_IRQ_ROUTING
2610 case KVM_CAP_IRQFD_RESAMPLE:
2611 #endif
2612 return 1;
2613 #ifdef CONFIG_HAVE_KVM_IRQ_ROUTING
2614 case KVM_CAP_IRQ_ROUTING:
2615 return KVM_MAX_IRQ_ROUTES;
2616 #endif
2617 default:
2618 break;
2619 }
2620 return kvm_dev_ioctl_check_extension(arg);
2621 }
2622
2623 static long kvm_dev_ioctl(struct file *filp,
2624 unsigned int ioctl, unsigned long arg)
2625 {
2626 long r = -EINVAL;
2627
2628 switch (ioctl) {
2629 case KVM_GET_API_VERSION:
2630 r = -EINVAL;
2631 if (arg)
2632 goto out;
2633 r = KVM_API_VERSION;
2634 break;
2635 case KVM_CREATE_VM:
2636 r = kvm_dev_ioctl_create_vm(arg);
2637 break;
2638 case KVM_CHECK_EXTENSION:
2639 r = kvm_dev_ioctl_check_extension_generic(arg);
2640 break;
2641 case KVM_GET_VCPU_MMAP_SIZE:
2642 r = -EINVAL;
2643 if (arg)
2644 goto out;
2645 r = PAGE_SIZE; /* struct kvm_run */
2646 #ifdef CONFIG_X86
2647 r += PAGE_SIZE; /* pio data page */
2648 #endif
2649 #ifdef KVM_COALESCED_MMIO_PAGE_OFFSET
2650 r += PAGE_SIZE; /* coalesced mmio ring page */
2651 #endif
2652 break;
2653 case KVM_TRACE_ENABLE:
2654 case KVM_TRACE_PAUSE:
2655 case KVM_TRACE_DISABLE:
2656 r = -EOPNOTSUPP;
2657 break;
2658 default:
2659 return kvm_arch_dev_ioctl(filp, ioctl, arg);
2660 }
2661 out:
2662 return r;
2663 }
2664
2665 static struct file_operations kvm_chardev_ops = {
2666 .unlocked_ioctl = kvm_dev_ioctl,
2667 .compat_ioctl = kvm_dev_ioctl,
2668 .llseek = noop_llseek,
2669 };
2670
2671 static struct miscdevice kvm_dev = {
2672 KVM_MINOR,
2673 "kvm",
2674 &kvm_chardev_ops,
2675 };
2676
2677 static void hardware_enable_nolock(void *junk)
2678 {
2679 int cpu = raw_smp_processor_id();
2680 int r;
2681
2682 if (cpumask_test_cpu(cpu, cpus_hardware_enabled))
2683 return;
2684
2685 cpumask_set_cpu(cpu, cpus_hardware_enabled);
2686
2687 r = kvm_arch_hardware_enable(NULL);
2688
2689 if (r) {
2690 cpumask_clear_cpu(cpu, cpus_hardware_enabled);
2691 atomic_inc(&hardware_enable_failed);
2692 printk(KERN_INFO "kvm: enabling virtualization on "
2693 "CPU%d failed\n", cpu);
2694 }
2695 }
2696
2697 static void hardware_enable(void *junk)
2698 {
2699 raw_spin_lock(&kvm_lock);
2700 hardware_enable_nolock(junk);
2701 raw_spin_unlock(&kvm_lock);
2702 }
2703
2704 static void hardware_disable_nolock(void *junk)
2705 {
2706 int cpu = raw_smp_processor_id();
2707
2708 if (!cpumask_test_cpu(cpu, cpus_hardware_enabled))
2709 return;
2710 cpumask_clear_cpu(cpu, cpus_hardware_enabled);
2711 kvm_arch_hardware_disable(NULL);
2712 }
2713
2714 static void hardware_disable(void *junk)
2715 {
2716 raw_spin_lock(&kvm_lock);
2717 hardware_disable_nolock(junk);
2718 raw_spin_unlock(&kvm_lock);
2719 }
2720
2721 static void hardware_disable_all_nolock(void)
2722 {
2723 BUG_ON(!kvm_usage_count);
2724
2725 kvm_usage_count--;
2726 if (!kvm_usage_count)
2727 on_each_cpu(hardware_disable_nolock, NULL, 1);
2728 }
2729
2730 static void hardware_disable_all(void)
2731 {
2732 raw_spin_lock(&kvm_lock);
2733 hardware_disable_all_nolock();
2734 raw_spin_unlock(&kvm_lock);
2735 }
2736
2737 static int hardware_enable_all(void)
2738 {
2739 int r = 0;
2740
2741 raw_spin_lock(&kvm_lock);
2742
2743 kvm_usage_count++;
2744 if (kvm_usage_count == 1) {
2745 atomic_set(&hardware_enable_failed, 0);
2746 on_each_cpu(hardware_enable_nolock, NULL, 1);
2747
2748 if (atomic_read(&hardware_enable_failed)) {
2749 hardware_disable_all_nolock();
2750 r = -EBUSY;
2751 }
2752 }
2753
2754 raw_spin_unlock(&kvm_lock);
2755
2756 return r;
2757 }
2758
2759 static int kvm_cpu_hotplug(struct notifier_block *notifier, unsigned long val,
2760 void *v)
2761 {
2762 int cpu = (long)v;
2763
2764 if (!kvm_usage_count)
2765 return NOTIFY_OK;
2766
2767 val &= ~CPU_TASKS_FROZEN;
2768 switch (val) {
2769 case CPU_DYING:
2770 printk(KERN_INFO "kvm: disabling virtualization on CPU%d\n",
2771 cpu);
2772 hardware_disable(NULL);
2773 break;
2774 case CPU_STARTING:
2775 printk(KERN_INFO "kvm: enabling virtualization on CPU%d\n",
2776 cpu);
2777 hardware_enable(NULL);
2778 break;
2779 }
2780 return NOTIFY_OK;
2781 }
2782
2783 static int kvm_reboot(struct notifier_block *notifier, unsigned long val,
2784 void *v)
2785 {
2786 /*
2787 * Some (well, at least mine) BIOSes hang on reboot if
2788 * in vmx root mode.
2789 *
2790 * And Intel TXT required VMX off for all cpu when system shutdown.
2791 */
2792 printk(KERN_INFO "kvm: exiting hardware virtualization\n");
2793 kvm_rebooting = true;
2794 on_each_cpu(hardware_disable_nolock, NULL, 1);
2795 return NOTIFY_OK;
2796 }
2797
2798 static struct notifier_block kvm_reboot_notifier = {
2799 .notifier_call = kvm_reboot,
2800 .priority = 0,
2801 };
2802
2803 static void kvm_io_bus_destroy(struct kvm_io_bus *bus)
2804 {
2805 int i;
2806
2807 for (i = 0; i < bus->dev_count; i++) {
2808 struct kvm_io_device *pos = bus->range[i].dev;
2809
2810 kvm_iodevice_destructor(pos);
2811 }
2812 kfree(bus);
2813 }
2814
2815 static int kvm_io_bus_sort_cmp(const void *p1, const void *p2)
2816 {
2817 const struct kvm_io_range *r1 = p1;
2818 const struct kvm_io_range *r2 = p2;
2819
2820 if (r1->addr < r2->addr)
2821 return -1;
2822 if (r1->addr + r1->len > r2->addr + r2->len)
2823 return 1;
2824 return 0;
2825 }
2826
2827 static int kvm_io_bus_insert_dev(struct kvm_io_bus *bus, struct kvm_io_device *dev,
2828 gpa_t addr, int len)
2829 {
2830 bus->range[bus->dev_count++] = (struct kvm_io_range) {
2831 .addr = addr,
2832 .len = len,
2833 .dev = dev,
2834 };
2835
2836 sort(bus->range, bus->dev_count, sizeof(struct kvm_io_range),
2837 kvm_io_bus_sort_cmp, NULL);
2838
2839 return 0;
2840 }
2841
2842 static int kvm_io_bus_get_first_dev(struct kvm_io_bus *bus,
2843 gpa_t addr, int len)
2844 {
2845 struct kvm_io_range *range, key;
2846 int off;
2847
2848 key = (struct kvm_io_range) {
2849 .addr = addr,
2850 .len = len,
2851 };
2852
2853 range = bsearch(&key, bus->range, bus->dev_count,
2854 sizeof(struct kvm_io_range), kvm_io_bus_sort_cmp);
2855 if (range == NULL)
2856 return -ENOENT;
2857
2858 off = range - bus->range;
2859
2860 while (off > 0 && kvm_io_bus_sort_cmp(&key, &bus->range[off-1]) == 0)
2861 off--;
2862
2863 return off;
2864 }
2865
2866 /* kvm_io_bus_write - called under kvm->slots_lock */
2867 int kvm_io_bus_write(struct kvm *kvm, enum kvm_bus bus_idx, gpa_t addr,
2868 int len, const void *val)
2869 {
2870 int idx;
2871 struct kvm_io_bus *bus;
2872 struct kvm_io_range range;
2873
2874 range = (struct kvm_io_range) {
2875 .addr = addr,
2876 .len = len,
2877 };
2878
2879 bus = srcu_dereference(kvm->buses[bus_idx], &kvm->srcu);
2880 idx = kvm_io_bus_get_first_dev(bus, addr, len);
2881 if (idx < 0)
2882 return -EOPNOTSUPP;
2883
2884 while (idx < bus->dev_count &&
2885 kvm_io_bus_sort_cmp(&range, &bus->range[idx]) == 0) {
2886 if (!kvm_iodevice_write(bus->range[idx].dev, addr, len, val))
2887 return 0;
2888 idx++;
2889 }
2890
2891 return -EOPNOTSUPP;
2892 }
2893
2894 /* kvm_io_bus_read - called under kvm->slots_lock */
2895 int kvm_io_bus_read(struct kvm *kvm, enum kvm_bus bus_idx, gpa_t addr,
2896 int len, void *val)
2897 {
2898 int idx;
2899 struct kvm_io_bus *bus;
2900 struct kvm_io_range range;
2901
2902 range = (struct kvm_io_range) {
2903 .addr = addr,
2904 .len = len,
2905 };
2906
2907 bus = srcu_dereference(kvm->buses[bus_idx], &kvm->srcu);
2908 idx = kvm_io_bus_get_first_dev(bus, addr, len);
2909 if (idx < 0)
2910 return -EOPNOTSUPP;
2911
2912 while (idx < bus->dev_count &&
2913 kvm_io_bus_sort_cmp(&range, &bus->range[idx]) == 0) {
2914 if (!kvm_iodevice_read(bus->range[idx].dev, addr, len, val))
2915 return 0;
2916 idx++;
2917 }
2918
2919 return -EOPNOTSUPP;
2920 }
2921
2922 /* Caller must hold slots_lock. */
2923 int kvm_io_bus_register_dev(struct kvm *kvm, enum kvm_bus bus_idx, gpa_t addr,
2924 int len, struct kvm_io_device *dev)
2925 {
2926 struct kvm_io_bus *new_bus, *bus;
2927
2928 bus = kvm->buses[bus_idx];
2929 /* exclude ioeventfd which is limited by maximum fd */
2930 if (bus->dev_count - bus->ioeventfd_count > NR_IOBUS_DEVS - 1)
2931 return -ENOSPC;
2932
2933 new_bus = kzalloc(sizeof(*bus) + ((bus->dev_count + 1) *
2934 sizeof(struct kvm_io_range)), GFP_KERNEL);
2935 if (!new_bus)
2936 return -ENOMEM;
2937 memcpy(new_bus, bus, sizeof(*bus) + (bus->dev_count *
2938 sizeof(struct kvm_io_range)));
2939 kvm_io_bus_insert_dev(new_bus, dev, addr, len);
2940 rcu_assign_pointer(kvm->buses[bus_idx], new_bus);
2941 synchronize_srcu_expedited(&kvm->srcu);
2942 kfree(bus);
2943
2944 return 0;
2945 }
2946
2947 /* Caller must hold slots_lock. */
2948 int kvm_io_bus_unregister_dev(struct kvm *kvm, enum kvm_bus bus_idx,
2949 struct kvm_io_device *dev)
2950 {
2951 int i, r;
2952 struct kvm_io_bus *new_bus, *bus;
2953
2954 bus = kvm->buses[bus_idx];
2955 r = -ENOENT;
2956 for (i = 0; i < bus->dev_count; i++)
2957 if (bus->range[i].dev == dev) {
2958 r = 0;
2959 break;
2960 }
2961
2962 if (r)
2963 return r;
2964
2965 new_bus = kzalloc(sizeof(*bus) + ((bus->dev_count - 1) *
2966 sizeof(struct kvm_io_range)), GFP_KERNEL);
2967 if (!new_bus)
2968 return -ENOMEM;
2969
2970 memcpy(new_bus, bus, sizeof(*bus) + i * sizeof(struct kvm_io_range));
2971 new_bus->dev_count--;
2972 memcpy(new_bus->range + i, bus->range + i + 1,
2973 (new_bus->dev_count - i) * sizeof(struct kvm_io_range));
2974
2975 rcu_assign_pointer(kvm->buses[bus_idx], new_bus);
2976 synchronize_srcu_expedited(&kvm->srcu);
2977 kfree(bus);
2978 return r;
2979 }
2980
2981 static struct notifier_block kvm_cpu_notifier = {
2982 .notifier_call = kvm_cpu_hotplug,
2983 };
2984
2985 static int vm_stat_get(void *_offset, u64 *val)
2986 {
2987 unsigned offset = (long)_offset;
2988 struct kvm *kvm;
2989
2990 *val = 0;
2991 raw_spin_lock(&kvm_lock);
2992 list_for_each_entry(kvm, &vm_list, vm_list)
2993 *val += *(u32 *)((void *)kvm + offset);
2994 raw_spin_unlock(&kvm_lock);
2995 return 0;
2996 }
2997
2998 DEFINE_SIMPLE_ATTRIBUTE(vm_stat_fops, vm_stat_get, NULL, "%llu\n");
2999
3000 static int vcpu_stat_get(void *_offset, u64 *val)
3001 {
3002 unsigned offset = (long)_offset;
3003 struct kvm *kvm;
3004 struct kvm_vcpu *vcpu;
3005 int i;
3006
3007 *val = 0;
3008 raw_spin_lock(&kvm_lock);
3009 list_for_each_entry(kvm, &vm_list, vm_list)
3010 kvm_for_each_vcpu(i, vcpu, kvm)
3011 *val += *(u32 *)((void *)vcpu + offset);
3012
3013 raw_spin_unlock(&kvm_lock);
3014 return 0;
3015 }
3016
3017 DEFINE_SIMPLE_ATTRIBUTE(vcpu_stat_fops, vcpu_stat_get, NULL, "%llu\n");
3018
3019 static const struct file_operations *stat_fops[] = {
3020 [KVM_STAT_VCPU] = &vcpu_stat_fops,
3021 [KVM_STAT_VM] = &vm_stat_fops,
3022 };
3023
3024 static int kvm_init_debug(void)
3025 {
3026 int r = -EFAULT;
3027 struct kvm_stats_debugfs_item *p;
3028
3029 kvm_debugfs_dir = debugfs_create_dir("kvm", NULL);
3030 if (kvm_debugfs_dir == NULL)
3031 goto out;
3032
3033 for (p = debugfs_entries; p->name; ++p) {
3034 p->dentry = debugfs_create_file(p->name, 0444, kvm_debugfs_dir,
3035 (void *)(long)p->offset,
3036 stat_fops[p->kind]);
3037 if (p->dentry == NULL)
3038 goto out_dir;
3039 }
3040
3041 return 0;
3042
3043 out_dir:
3044 debugfs_remove_recursive(kvm_debugfs_dir);
3045 out:
3046 return r;
3047 }
3048
3049 static void kvm_exit_debug(void)
3050 {
3051 struct kvm_stats_debugfs_item *p;
3052
3053 for (p = debugfs_entries; p->name; ++p)
3054 debugfs_remove(p->dentry);
3055 debugfs_remove(kvm_debugfs_dir);
3056 }
3057
3058 static int kvm_suspend(void)
3059 {
3060 if (kvm_usage_count)
3061 hardware_disable_nolock(NULL);
3062 return 0;
3063 }
3064
3065 static void kvm_resume(void)
3066 {
3067 if (kvm_usage_count) {
3068 WARN_ON(raw_spin_is_locked(&kvm_lock));
3069 hardware_enable_nolock(NULL);
3070 }
3071 }
3072
3073 static struct syscore_ops kvm_syscore_ops = {
3074 .suspend = kvm_suspend,
3075 .resume = kvm_resume,
3076 };
3077
3078 static inline
3079 struct kvm_vcpu *preempt_notifier_to_vcpu(struct preempt_notifier *pn)
3080 {
3081 return container_of(pn, struct kvm_vcpu, preempt_notifier);
3082 }
3083
3084 static void kvm_sched_in(struct preempt_notifier *pn, int cpu)
3085 {
3086 struct kvm_vcpu *vcpu = preempt_notifier_to_vcpu(pn);
3087 if (vcpu->preempted)
3088 vcpu->preempted = false;
3089
3090 kvm_arch_vcpu_load(vcpu, cpu);
3091 }
3092
3093 static void kvm_sched_out(struct preempt_notifier *pn,
3094 struct task_struct *next)
3095 {
3096 struct kvm_vcpu *vcpu = preempt_notifier_to_vcpu(pn);
3097
3098 if (current->state == TASK_RUNNING)
3099 vcpu->preempted = true;
3100 kvm_arch_vcpu_put(vcpu);
3101 }
3102
3103 int kvm_init(void *opaque, unsigned vcpu_size, unsigned vcpu_align,
3104 struct module *module)
3105 {
3106 int r;
3107 int cpu;
3108
3109 r = kvm_arch_init(opaque);
3110 if (r)
3111 goto out_fail;
3112
3113 /*
3114 * kvm_arch_init makes sure there's at most one caller
3115 * for architectures that support multiple implementations,
3116 * like intel and amd on x86.
3117 * kvm_arch_init must be called before kvm_irqfd_init to avoid creating
3118 * conflicts in case kvm is already setup for another implementation.
3119 */
3120 r = kvm_irqfd_init();
3121 if (r)
3122 goto out_irqfd;
3123
3124 if (!zalloc_cpumask_var(&cpus_hardware_enabled, GFP_KERNEL)) {
3125 r = -ENOMEM;
3126 goto out_free_0;
3127 }
3128
3129 r = kvm_arch_hardware_setup();
3130 if (r < 0)
3131 goto out_free_0a;
3132
3133 for_each_online_cpu(cpu) {
3134 smp_call_function_single(cpu,
3135 kvm_arch_check_processor_compat,
3136 &r, 1);
3137 if (r < 0)
3138 goto out_free_1;
3139 }
3140
3141 r = register_cpu_notifier(&kvm_cpu_notifier);
3142 if (r)
3143 goto out_free_2;
3144 register_reboot_notifier(&kvm_reboot_notifier);
3145
3146 /* A kmem cache lets us meet the alignment requirements of fx_save. */
3147 if (!vcpu_align)
3148 vcpu_align = __alignof__(struct kvm_vcpu);
3149 kvm_vcpu_cache = kmem_cache_create("kvm_vcpu", vcpu_size, vcpu_align,
3150 0, NULL);
3151 if (!kvm_vcpu_cache) {
3152 r = -ENOMEM;
3153 goto out_free_3;
3154 }
3155
3156 r = kvm_async_pf_init();
3157 if (r)
3158 goto out_free;
3159
3160 kvm_chardev_ops.owner = module;
3161 kvm_vm_fops.owner = module;
3162 kvm_vcpu_fops.owner = module;
3163
3164 r = misc_register(&kvm_dev);
3165 if (r) {
3166 printk(KERN_ERR "kvm: misc device register failed\n");
3167 goto out_unreg;
3168 }
3169
3170 register_syscore_ops(&kvm_syscore_ops);
3171
3172 kvm_preempt_ops.sched_in = kvm_sched_in;
3173 kvm_preempt_ops.sched_out = kvm_sched_out;
3174
3175 r = kvm_init_debug();
3176 if (r) {
3177 printk(KERN_ERR "kvm: create debugfs files failed\n");
3178 goto out_undebugfs;
3179 }
3180
3181 return 0;
3182
3183 out_undebugfs:
3184 unregister_syscore_ops(&kvm_syscore_ops);
3185 misc_deregister(&kvm_dev);
3186 out_unreg:
3187 kvm_async_pf_deinit();
3188 out_free:
3189 kmem_cache_destroy(kvm_vcpu_cache);
3190 out_free_3:
3191 unregister_reboot_notifier(&kvm_reboot_notifier);
3192 unregister_cpu_notifier(&kvm_cpu_notifier);
3193 out_free_2:
3194 out_free_1:
3195 kvm_arch_hardware_unsetup();
3196 out_free_0a:
3197 free_cpumask_var(cpus_hardware_enabled);
3198 out_free_0:
3199 kvm_irqfd_exit();
3200 out_irqfd:
3201 kvm_arch_exit();
3202 out_fail:
3203 return r;
3204 }
3205 EXPORT_SYMBOL_GPL(kvm_init);
3206
3207 void kvm_exit(void)
3208 {
3209 kvm_exit_debug();
3210 misc_deregister(&kvm_dev);
3211 kmem_cache_destroy(kvm_vcpu_cache);
3212 kvm_async_pf_deinit();
3213 unregister_syscore_ops(&kvm_syscore_ops);
3214 unregister_reboot_notifier(&kvm_reboot_notifier);
3215 unregister_cpu_notifier(&kvm_cpu_notifier);
3216 on_each_cpu(hardware_disable_nolock, NULL, 1);
3217 kvm_arch_hardware_unsetup();
3218 kvm_arch_exit();
3219 kvm_irqfd_exit();
3220 free_cpumask_var(cpus_hardware_enabled);
3221 }
3222 EXPORT_SYMBOL_GPL(kvm_exit);
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