xref: /linux/virt/kvm/kvm_main.c (revision 3eeebf17f31c583f83e081b17b3076477cb96886)
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  *
9  * Authors:
10  *   Avi Kivity   <avi@qumranet.com>
11  *   Yaniv Kamay  <yaniv@qumranet.com>
12  *
13  * This work is licensed under the terms of the GNU GPL, version 2.  See
14  * the COPYING file in the top-level directory.
15  *
16  */
17 
18 #include "iodev.h"
19 
20 #include <linux/kvm_host.h>
21 #include <linux/kvm.h>
22 #include <linux/module.h>
23 #include <linux/errno.h>
24 #include <linux/percpu.h>
25 #include <linux/gfp.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 
45 #include <asm/processor.h>
46 #include <asm/io.h>
47 #include <asm/uaccess.h>
48 #include <asm/pgtable.h>
49 
50 #ifdef KVM_COALESCED_MMIO_PAGE_OFFSET
51 #include "coalesced_mmio.h"
52 #endif
53 
54 #ifdef KVM_CAP_DEVICE_ASSIGNMENT
55 #include <linux/pci.h>
56 #include <linux/interrupt.h>
57 #include "irq.h"
58 #endif
59 
60 MODULE_AUTHOR("Qumranet");
61 MODULE_LICENSE("GPL");
62 
63 DEFINE_SPINLOCK(kvm_lock);
64 LIST_HEAD(vm_list);
65 
66 static cpumask_t cpus_hardware_enabled;
67 
68 struct kmem_cache *kvm_vcpu_cache;
69 EXPORT_SYMBOL_GPL(kvm_vcpu_cache);
70 
71 static __read_mostly struct preempt_ops kvm_preempt_ops;
72 
73 struct dentry *kvm_debugfs_dir;
74 
75 static long kvm_vcpu_ioctl(struct file *file, unsigned int ioctl,
76 			   unsigned long arg);
77 
78 bool kvm_rebooting;
79 
80 #ifdef KVM_CAP_DEVICE_ASSIGNMENT
81 static struct kvm_assigned_dev_kernel *kvm_find_assigned_dev(struct list_head *head,
82 						      int assigned_dev_id)
83 {
84 	struct list_head *ptr;
85 	struct kvm_assigned_dev_kernel *match;
86 
87 	list_for_each(ptr, head) {
88 		match = list_entry(ptr, struct kvm_assigned_dev_kernel, list);
89 		if (match->assigned_dev_id == assigned_dev_id)
90 			return match;
91 	}
92 	return NULL;
93 }
94 
95 static void kvm_assigned_dev_interrupt_work_handler(struct work_struct *work)
96 {
97 	struct kvm_assigned_dev_kernel *assigned_dev;
98 
99 	assigned_dev = container_of(work, struct kvm_assigned_dev_kernel,
100 				    interrupt_work);
101 
102 	/* This is taken to safely inject irq inside the guest. When
103 	 * the interrupt injection (or the ioapic code) uses a
104 	 * finer-grained lock, update this
105 	 */
106 	mutex_lock(&assigned_dev->kvm->lock);
107 	kvm_set_irq(assigned_dev->kvm,
108 		    assigned_dev->guest_irq, 1);
109 	mutex_unlock(&assigned_dev->kvm->lock);
110 	kvm_put_kvm(assigned_dev->kvm);
111 }
112 
113 /* FIXME: Implement the OR logic needed to make shared interrupts on
114  * this line behave properly
115  */
116 static irqreturn_t kvm_assigned_dev_intr(int irq, void *dev_id)
117 {
118 	struct kvm_assigned_dev_kernel *assigned_dev =
119 		(struct kvm_assigned_dev_kernel *) dev_id;
120 
121 	kvm_get_kvm(assigned_dev->kvm);
122 	schedule_work(&assigned_dev->interrupt_work);
123 	disable_irq_nosync(irq);
124 	return IRQ_HANDLED;
125 }
126 
127 /* Ack the irq line for an assigned device */
128 static void kvm_assigned_dev_ack_irq(struct kvm_irq_ack_notifier *kian)
129 {
130 	struct kvm_assigned_dev_kernel *dev;
131 
132 	if (kian->gsi == -1)
133 		return;
134 
135 	dev = container_of(kian, struct kvm_assigned_dev_kernel,
136 			   ack_notifier);
137 	kvm_set_irq(dev->kvm, dev->guest_irq, 0);
138 	enable_irq(dev->host_irq);
139 }
140 
141 static void kvm_free_assigned_device(struct kvm *kvm,
142 				     struct kvm_assigned_dev_kernel
143 				     *assigned_dev)
144 {
145 	if (irqchip_in_kernel(kvm) && assigned_dev->irq_requested)
146 		free_irq(assigned_dev->host_irq, (void *)assigned_dev);
147 
148 	kvm_unregister_irq_ack_notifier(kvm, &assigned_dev->ack_notifier);
149 
150 	if (cancel_work_sync(&assigned_dev->interrupt_work))
151 		/* We had pending work. That means we will have to take
152 		 * care of kvm_put_kvm.
153 		 */
154 		kvm_put_kvm(kvm);
155 
156 	pci_release_regions(assigned_dev->dev);
157 	pci_disable_device(assigned_dev->dev);
158 	pci_dev_put(assigned_dev->dev);
159 
160 	list_del(&assigned_dev->list);
161 	kfree(assigned_dev);
162 }
163 
164 void kvm_free_all_assigned_devices(struct kvm *kvm)
165 {
166 	struct list_head *ptr, *ptr2;
167 	struct kvm_assigned_dev_kernel *assigned_dev;
168 
169 	list_for_each_safe(ptr, ptr2, &kvm->arch.assigned_dev_head) {
170 		assigned_dev = list_entry(ptr,
171 					  struct kvm_assigned_dev_kernel,
172 					  list);
173 
174 		kvm_free_assigned_device(kvm, assigned_dev);
175 	}
176 }
177 
178 static int kvm_vm_ioctl_assign_irq(struct kvm *kvm,
179 				   struct kvm_assigned_irq
180 				   *assigned_irq)
181 {
182 	int r = 0;
183 	struct kvm_assigned_dev_kernel *match;
184 
185 	mutex_lock(&kvm->lock);
186 
187 	match = kvm_find_assigned_dev(&kvm->arch.assigned_dev_head,
188 				      assigned_irq->assigned_dev_id);
189 	if (!match) {
190 		mutex_unlock(&kvm->lock);
191 		return -EINVAL;
192 	}
193 
194 	if (match->irq_requested) {
195 		match->guest_irq = assigned_irq->guest_irq;
196 		match->ack_notifier.gsi = assigned_irq->guest_irq;
197 		mutex_unlock(&kvm->lock);
198 		return 0;
199 	}
200 
201 	INIT_WORK(&match->interrupt_work,
202 		  kvm_assigned_dev_interrupt_work_handler);
203 
204 	if (irqchip_in_kernel(kvm)) {
205 		if (!capable(CAP_SYS_RAWIO)) {
206 			r = -EPERM;
207 			goto out_release;
208 		}
209 
210 		if (assigned_irq->host_irq)
211 			match->host_irq = assigned_irq->host_irq;
212 		else
213 			match->host_irq = match->dev->irq;
214 		match->guest_irq = assigned_irq->guest_irq;
215 		match->ack_notifier.gsi = assigned_irq->guest_irq;
216 		match->ack_notifier.irq_acked = kvm_assigned_dev_ack_irq;
217 		kvm_register_irq_ack_notifier(kvm, &match->ack_notifier);
218 
219 		/* Even though this is PCI, we don't want to use shared
220 		 * interrupts. Sharing host devices with guest-assigned devices
221 		 * on the same interrupt line is not a happy situation: there
222 		 * are going to be long delays in accepting, acking, etc.
223 		 */
224 		if (request_irq(match->host_irq, kvm_assigned_dev_intr, 0,
225 				"kvm_assigned_device", (void *)match)) {
226 			r = -EIO;
227 			goto out_release;
228 		}
229 	}
230 
231 	match->irq_requested = true;
232 	mutex_unlock(&kvm->lock);
233 	return r;
234 out_release:
235 	mutex_unlock(&kvm->lock);
236 	kvm_free_assigned_device(kvm, match);
237 	return r;
238 }
239 
240 static int kvm_vm_ioctl_assign_device(struct kvm *kvm,
241 				      struct kvm_assigned_pci_dev *assigned_dev)
242 {
243 	int r = 0;
244 	struct kvm_assigned_dev_kernel *match;
245 	struct pci_dev *dev;
246 
247 	mutex_lock(&kvm->lock);
248 
249 	match = kvm_find_assigned_dev(&kvm->arch.assigned_dev_head,
250 				      assigned_dev->assigned_dev_id);
251 	if (match) {
252 		/* device already assigned */
253 		r = -EINVAL;
254 		goto out;
255 	}
256 
257 	match = kzalloc(sizeof(struct kvm_assigned_dev_kernel), GFP_KERNEL);
258 	if (match == NULL) {
259 		printk(KERN_INFO "%s: Couldn't allocate memory\n",
260 		       __func__);
261 		r = -ENOMEM;
262 		goto out;
263 	}
264 	dev = pci_get_bus_and_slot(assigned_dev->busnr,
265 				   assigned_dev->devfn);
266 	if (!dev) {
267 		printk(KERN_INFO "%s: host device not found\n", __func__);
268 		r = -EINVAL;
269 		goto out_free;
270 	}
271 	if (pci_enable_device(dev)) {
272 		printk(KERN_INFO "%s: Could not enable PCI device\n", __func__);
273 		r = -EBUSY;
274 		goto out_put;
275 	}
276 	r = pci_request_regions(dev, "kvm_assigned_device");
277 	if (r) {
278 		printk(KERN_INFO "%s: Could not get access to device regions\n",
279 		       __func__);
280 		goto out_disable;
281 	}
282 	match->assigned_dev_id = assigned_dev->assigned_dev_id;
283 	match->host_busnr = assigned_dev->busnr;
284 	match->host_devfn = assigned_dev->devfn;
285 	match->dev = dev;
286 
287 	match->kvm = kvm;
288 
289 	list_add(&match->list, &kvm->arch.assigned_dev_head);
290 
291 	if (assigned_dev->flags & KVM_DEV_ASSIGN_ENABLE_IOMMU) {
292 		r = kvm_iommu_map_guest(kvm, match);
293 		if (r)
294 			goto out_list_del;
295 	}
296 
297 out:
298 	mutex_unlock(&kvm->lock);
299 	return r;
300 out_list_del:
301 	list_del(&match->list);
302 	pci_release_regions(dev);
303 out_disable:
304 	pci_disable_device(dev);
305 out_put:
306 	pci_dev_put(dev);
307 out_free:
308 	kfree(match);
309 	mutex_unlock(&kvm->lock);
310 	return r;
311 }
312 #endif
313 
314 static inline int valid_vcpu(int n)
315 {
316 	return likely(n >= 0 && n < KVM_MAX_VCPUS);
317 }
318 
319 inline int kvm_is_mmio_pfn(pfn_t pfn)
320 {
321 	if (pfn_valid(pfn))
322 		return PageReserved(pfn_to_page(pfn));
323 
324 	return true;
325 }
326 
327 /*
328  * Switches to specified vcpu, until a matching vcpu_put()
329  */
330 void vcpu_load(struct kvm_vcpu *vcpu)
331 {
332 	int cpu;
333 
334 	mutex_lock(&vcpu->mutex);
335 	cpu = get_cpu();
336 	preempt_notifier_register(&vcpu->preempt_notifier);
337 	kvm_arch_vcpu_load(vcpu, cpu);
338 	put_cpu();
339 }
340 
341 void vcpu_put(struct kvm_vcpu *vcpu)
342 {
343 	preempt_disable();
344 	kvm_arch_vcpu_put(vcpu);
345 	preempt_notifier_unregister(&vcpu->preempt_notifier);
346 	preempt_enable();
347 	mutex_unlock(&vcpu->mutex);
348 }
349 
350 static void ack_flush(void *_completed)
351 {
352 }
353 
354 void kvm_flush_remote_tlbs(struct kvm *kvm)
355 {
356 	int i, cpu, me;
357 	cpumask_t cpus;
358 	struct kvm_vcpu *vcpu;
359 
360 	me = get_cpu();
361 	cpus_clear(cpus);
362 	for (i = 0; i < KVM_MAX_VCPUS; ++i) {
363 		vcpu = kvm->vcpus[i];
364 		if (!vcpu)
365 			continue;
366 		if (test_and_set_bit(KVM_REQ_TLB_FLUSH, &vcpu->requests))
367 			continue;
368 		cpu = vcpu->cpu;
369 		if (cpu != -1 && cpu != me)
370 			cpu_set(cpu, cpus);
371 	}
372 	if (cpus_empty(cpus))
373 		goto out;
374 	++kvm->stat.remote_tlb_flush;
375 	smp_call_function_mask(cpus, ack_flush, NULL, 1);
376 out:
377 	put_cpu();
378 }
379 
380 void kvm_reload_remote_mmus(struct kvm *kvm)
381 {
382 	int i, cpu, me;
383 	cpumask_t cpus;
384 	struct kvm_vcpu *vcpu;
385 
386 	me = get_cpu();
387 	cpus_clear(cpus);
388 	for (i = 0; i < KVM_MAX_VCPUS; ++i) {
389 		vcpu = kvm->vcpus[i];
390 		if (!vcpu)
391 			continue;
392 		if (test_and_set_bit(KVM_REQ_MMU_RELOAD, &vcpu->requests))
393 			continue;
394 		cpu = vcpu->cpu;
395 		if (cpu != -1 && cpu != me)
396 			cpu_set(cpu, cpus);
397 	}
398 	if (cpus_empty(cpus))
399 		goto out;
400 	smp_call_function_mask(cpus, ack_flush, NULL, 1);
401 out:
402 	put_cpu();
403 }
404 
405 
406 int kvm_vcpu_init(struct kvm_vcpu *vcpu, struct kvm *kvm, unsigned id)
407 {
408 	struct page *page;
409 	int r;
410 
411 	mutex_init(&vcpu->mutex);
412 	vcpu->cpu = -1;
413 	vcpu->kvm = kvm;
414 	vcpu->vcpu_id = id;
415 	init_waitqueue_head(&vcpu->wq);
416 
417 	page = alloc_page(GFP_KERNEL | __GFP_ZERO);
418 	if (!page) {
419 		r = -ENOMEM;
420 		goto fail;
421 	}
422 	vcpu->run = page_address(page);
423 
424 	r = kvm_arch_vcpu_init(vcpu);
425 	if (r < 0)
426 		goto fail_free_run;
427 	return 0;
428 
429 fail_free_run:
430 	free_page((unsigned long)vcpu->run);
431 fail:
432 	return r;
433 }
434 EXPORT_SYMBOL_GPL(kvm_vcpu_init);
435 
436 void kvm_vcpu_uninit(struct kvm_vcpu *vcpu)
437 {
438 	kvm_arch_vcpu_uninit(vcpu);
439 	free_page((unsigned long)vcpu->run);
440 }
441 EXPORT_SYMBOL_GPL(kvm_vcpu_uninit);
442 
443 #if defined(CONFIG_MMU_NOTIFIER) && defined(KVM_ARCH_WANT_MMU_NOTIFIER)
444 static inline struct kvm *mmu_notifier_to_kvm(struct mmu_notifier *mn)
445 {
446 	return container_of(mn, struct kvm, mmu_notifier);
447 }
448 
449 static void kvm_mmu_notifier_invalidate_page(struct mmu_notifier *mn,
450 					     struct mm_struct *mm,
451 					     unsigned long address)
452 {
453 	struct kvm *kvm = mmu_notifier_to_kvm(mn);
454 	int need_tlb_flush;
455 
456 	/*
457 	 * When ->invalidate_page runs, the linux pte has been zapped
458 	 * already but the page is still allocated until
459 	 * ->invalidate_page returns. So if we increase the sequence
460 	 * here the kvm page fault will notice if the spte can't be
461 	 * established because the page is going to be freed. If
462 	 * instead the kvm page fault establishes the spte before
463 	 * ->invalidate_page runs, kvm_unmap_hva will release it
464 	 * before returning.
465 	 *
466 	 * The sequence increase only need to be seen at spin_unlock
467 	 * time, and not at spin_lock time.
468 	 *
469 	 * Increasing the sequence after the spin_unlock would be
470 	 * unsafe because the kvm page fault could then establish the
471 	 * pte after kvm_unmap_hva returned, without noticing the page
472 	 * is going to be freed.
473 	 */
474 	spin_lock(&kvm->mmu_lock);
475 	kvm->mmu_notifier_seq++;
476 	need_tlb_flush = kvm_unmap_hva(kvm, address);
477 	spin_unlock(&kvm->mmu_lock);
478 
479 	/* we've to flush the tlb before the pages can be freed */
480 	if (need_tlb_flush)
481 		kvm_flush_remote_tlbs(kvm);
482 
483 }
484 
485 static void kvm_mmu_notifier_invalidate_range_start(struct mmu_notifier *mn,
486 						    struct mm_struct *mm,
487 						    unsigned long start,
488 						    unsigned long end)
489 {
490 	struct kvm *kvm = mmu_notifier_to_kvm(mn);
491 	int need_tlb_flush = 0;
492 
493 	spin_lock(&kvm->mmu_lock);
494 	/*
495 	 * The count increase must become visible at unlock time as no
496 	 * spte can be established without taking the mmu_lock and
497 	 * count is also read inside the mmu_lock critical section.
498 	 */
499 	kvm->mmu_notifier_count++;
500 	for (; start < end; start += PAGE_SIZE)
501 		need_tlb_flush |= kvm_unmap_hva(kvm, start);
502 	spin_unlock(&kvm->mmu_lock);
503 
504 	/* we've to flush the tlb before the pages can be freed */
505 	if (need_tlb_flush)
506 		kvm_flush_remote_tlbs(kvm);
507 }
508 
509 static void kvm_mmu_notifier_invalidate_range_end(struct mmu_notifier *mn,
510 						  struct mm_struct *mm,
511 						  unsigned long start,
512 						  unsigned long end)
513 {
514 	struct kvm *kvm = mmu_notifier_to_kvm(mn);
515 
516 	spin_lock(&kvm->mmu_lock);
517 	/*
518 	 * This sequence increase will notify the kvm page fault that
519 	 * the page that is going to be mapped in the spte could have
520 	 * been freed.
521 	 */
522 	kvm->mmu_notifier_seq++;
523 	/*
524 	 * The above sequence increase must be visible before the
525 	 * below count decrease but both values are read by the kvm
526 	 * page fault under mmu_lock spinlock so we don't need to add
527 	 * a smb_wmb() here in between the two.
528 	 */
529 	kvm->mmu_notifier_count--;
530 	spin_unlock(&kvm->mmu_lock);
531 
532 	BUG_ON(kvm->mmu_notifier_count < 0);
533 }
534 
535 static int kvm_mmu_notifier_clear_flush_young(struct mmu_notifier *mn,
536 					      struct mm_struct *mm,
537 					      unsigned long address)
538 {
539 	struct kvm *kvm = mmu_notifier_to_kvm(mn);
540 	int young;
541 
542 	spin_lock(&kvm->mmu_lock);
543 	young = kvm_age_hva(kvm, address);
544 	spin_unlock(&kvm->mmu_lock);
545 
546 	if (young)
547 		kvm_flush_remote_tlbs(kvm);
548 
549 	return young;
550 }
551 
552 static const struct mmu_notifier_ops kvm_mmu_notifier_ops = {
553 	.invalidate_page	= kvm_mmu_notifier_invalidate_page,
554 	.invalidate_range_start	= kvm_mmu_notifier_invalidate_range_start,
555 	.invalidate_range_end	= kvm_mmu_notifier_invalidate_range_end,
556 	.clear_flush_young	= kvm_mmu_notifier_clear_flush_young,
557 };
558 #endif /* CONFIG_MMU_NOTIFIER && KVM_ARCH_WANT_MMU_NOTIFIER */
559 
560 static struct kvm *kvm_create_vm(void)
561 {
562 	struct kvm *kvm = kvm_arch_create_vm();
563 #ifdef KVM_COALESCED_MMIO_PAGE_OFFSET
564 	struct page *page;
565 #endif
566 
567 	if (IS_ERR(kvm))
568 		goto out;
569 
570 #ifdef KVM_COALESCED_MMIO_PAGE_OFFSET
571 	page = alloc_page(GFP_KERNEL | __GFP_ZERO);
572 	if (!page) {
573 		kfree(kvm);
574 		return ERR_PTR(-ENOMEM);
575 	}
576 	kvm->coalesced_mmio_ring =
577 			(struct kvm_coalesced_mmio_ring *)page_address(page);
578 #endif
579 
580 #if defined(CONFIG_MMU_NOTIFIER) && defined(KVM_ARCH_WANT_MMU_NOTIFIER)
581 	{
582 		int err;
583 		kvm->mmu_notifier.ops = &kvm_mmu_notifier_ops;
584 		err = mmu_notifier_register(&kvm->mmu_notifier, current->mm);
585 		if (err) {
586 #ifdef KVM_COALESCED_MMIO_PAGE_OFFSET
587 			put_page(page);
588 #endif
589 			kfree(kvm);
590 			return ERR_PTR(err);
591 		}
592 	}
593 #endif
594 
595 	kvm->mm = current->mm;
596 	atomic_inc(&kvm->mm->mm_count);
597 	spin_lock_init(&kvm->mmu_lock);
598 	kvm_io_bus_init(&kvm->pio_bus);
599 	mutex_init(&kvm->lock);
600 	kvm_io_bus_init(&kvm->mmio_bus);
601 	init_rwsem(&kvm->slots_lock);
602 	atomic_set(&kvm->users_count, 1);
603 	spin_lock(&kvm_lock);
604 	list_add(&kvm->vm_list, &vm_list);
605 	spin_unlock(&kvm_lock);
606 #ifdef KVM_COALESCED_MMIO_PAGE_OFFSET
607 	kvm_coalesced_mmio_init(kvm);
608 #endif
609 out:
610 	return kvm;
611 }
612 
613 /*
614  * Free any memory in @free but not in @dont.
615  */
616 static void kvm_free_physmem_slot(struct kvm_memory_slot *free,
617 				  struct kvm_memory_slot *dont)
618 {
619 	if (!dont || free->rmap != dont->rmap)
620 		vfree(free->rmap);
621 
622 	if (!dont || free->dirty_bitmap != dont->dirty_bitmap)
623 		vfree(free->dirty_bitmap);
624 
625 	if (!dont || free->lpage_info != dont->lpage_info)
626 		vfree(free->lpage_info);
627 
628 	free->npages = 0;
629 	free->dirty_bitmap = NULL;
630 	free->rmap = NULL;
631 	free->lpage_info = NULL;
632 }
633 
634 void kvm_free_physmem(struct kvm *kvm)
635 {
636 	int i;
637 
638 	for (i = 0; i < kvm->nmemslots; ++i)
639 		kvm_free_physmem_slot(&kvm->memslots[i], NULL);
640 }
641 
642 static void kvm_destroy_vm(struct kvm *kvm)
643 {
644 	struct mm_struct *mm = kvm->mm;
645 
646 	spin_lock(&kvm_lock);
647 	list_del(&kvm->vm_list);
648 	spin_unlock(&kvm_lock);
649 	kvm_io_bus_destroy(&kvm->pio_bus);
650 	kvm_io_bus_destroy(&kvm->mmio_bus);
651 #ifdef KVM_COALESCED_MMIO_PAGE_OFFSET
652 	if (kvm->coalesced_mmio_ring != NULL)
653 		free_page((unsigned long)kvm->coalesced_mmio_ring);
654 #endif
655 #if defined(CONFIG_MMU_NOTIFIER) && defined(KVM_ARCH_WANT_MMU_NOTIFIER)
656 	mmu_notifier_unregister(&kvm->mmu_notifier, kvm->mm);
657 #endif
658 	kvm_arch_destroy_vm(kvm);
659 	mmdrop(mm);
660 }
661 
662 void kvm_get_kvm(struct kvm *kvm)
663 {
664 	atomic_inc(&kvm->users_count);
665 }
666 EXPORT_SYMBOL_GPL(kvm_get_kvm);
667 
668 void kvm_put_kvm(struct kvm *kvm)
669 {
670 	if (atomic_dec_and_test(&kvm->users_count))
671 		kvm_destroy_vm(kvm);
672 }
673 EXPORT_SYMBOL_GPL(kvm_put_kvm);
674 
675 
676 static int kvm_vm_release(struct inode *inode, struct file *filp)
677 {
678 	struct kvm *kvm = filp->private_data;
679 
680 	kvm_put_kvm(kvm);
681 	return 0;
682 }
683 
684 /*
685  * Allocate some memory and give it an address in the guest physical address
686  * space.
687  *
688  * Discontiguous memory is allowed, mostly for framebuffers.
689  *
690  * Must be called holding mmap_sem for write.
691  */
692 int __kvm_set_memory_region(struct kvm *kvm,
693 			    struct kvm_userspace_memory_region *mem,
694 			    int user_alloc)
695 {
696 	int r;
697 	gfn_t base_gfn;
698 	unsigned long npages;
699 	unsigned long i;
700 	struct kvm_memory_slot *memslot;
701 	struct kvm_memory_slot old, new;
702 
703 	r = -EINVAL;
704 	/* General sanity checks */
705 	if (mem->memory_size & (PAGE_SIZE - 1))
706 		goto out;
707 	if (mem->guest_phys_addr & (PAGE_SIZE - 1))
708 		goto out;
709 	if (mem->slot >= KVM_MEMORY_SLOTS + KVM_PRIVATE_MEM_SLOTS)
710 		goto out;
711 	if (mem->guest_phys_addr + mem->memory_size < mem->guest_phys_addr)
712 		goto out;
713 
714 	memslot = &kvm->memslots[mem->slot];
715 	base_gfn = mem->guest_phys_addr >> PAGE_SHIFT;
716 	npages = mem->memory_size >> PAGE_SHIFT;
717 
718 	if (!npages)
719 		mem->flags &= ~KVM_MEM_LOG_DIRTY_PAGES;
720 
721 	new = old = *memslot;
722 
723 	new.base_gfn = base_gfn;
724 	new.npages = npages;
725 	new.flags = mem->flags;
726 
727 	/* Disallow changing a memory slot's size. */
728 	r = -EINVAL;
729 	if (npages && old.npages && npages != old.npages)
730 		goto out_free;
731 
732 	/* Check for overlaps */
733 	r = -EEXIST;
734 	for (i = 0; i < KVM_MEMORY_SLOTS; ++i) {
735 		struct kvm_memory_slot *s = &kvm->memslots[i];
736 
737 		if (s == memslot)
738 			continue;
739 		if (!((base_gfn + npages <= s->base_gfn) ||
740 		      (base_gfn >= s->base_gfn + s->npages)))
741 			goto out_free;
742 	}
743 
744 	/* Free page dirty bitmap if unneeded */
745 	if (!(new.flags & KVM_MEM_LOG_DIRTY_PAGES))
746 		new.dirty_bitmap = NULL;
747 
748 	r = -ENOMEM;
749 
750 	/* Allocate if a slot is being created */
751 #ifndef CONFIG_S390
752 	if (npages && !new.rmap) {
753 		new.rmap = vmalloc(npages * sizeof(struct page *));
754 
755 		if (!new.rmap)
756 			goto out_free;
757 
758 		memset(new.rmap, 0, npages * sizeof(*new.rmap));
759 
760 		new.user_alloc = user_alloc;
761 		/*
762 		 * hva_to_rmmap() serialzies with the mmu_lock and to be
763 		 * safe it has to ignore memslots with !user_alloc &&
764 		 * !userspace_addr.
765 		 */
766 		if (user_alloc)
767 			new.userspace_addr = mem->userspace_addr;
768 		else
769 			new.userspace_addr = 0;
770 	}
771 	if (npages && !new.lpage_info) {
772 		int largepages = npages / KVM_PAGES_PER_HPAGE;
773 		if (npages % KVM_PAGES_PER_HPAGE)
774 			largepages++;
775 		if (base_gfn % KVM_PAGES_PER_HPAGE)
776 			largepages++;
777 
778 		new.lpage_info = vmalloc(largepages * sizeof(*new.lpage_info));
779 
780 		if (!new.lpage_info)
781 			goto out_free;
782 
783 		memset(new.lpage_info, 0, largepages * sizeof(*new.lpage_info));
784 
785 		if (base_gfn % KVM_PAGES_PER_HPAGE)
786 			new.lpage_info[0].write_count = 1;
787 		if ((base_gfn+npages) % KVM_PAGES_PER_HPAGE)
788 			new.lpage_info[largepages-1].write_count = 1;
789 	}
790 
791 	/* Allocate page dirty bitmap if needed */
792 	if ((new.flags & KVM_MEM_LOG_DIRTY_PAGES) && !new.dirty_bitmap) {
793 		unsigned dirty_bytes = ALIGN(npages, BITS_PER_LONG) / 8;
794 
795 		new.dirty_bitmap = vmalloc(dirty_bytes);
796 		if (!new.dirty_bitmap)
797 			goto out_free;
798 		memset(new.dirty_bitmap, 0, dirty_bytes);
799 	}
800 #endif /* not defined CONFIG_S390 */
801 
802 	if (!npages)
803 		kvm_arch_flush_shadow(kvm);
804 
805 	spin_lock(&kvm->mmu_lock);
806 	if (mem->slot >= kvm->nmemslots)
807 		kvm->nmemslots = mem->slot + 1;
808 
809 	*memslot = new;
810 	spin_unlock(&kvm->mmu_lock);
811 
812 	r = kvm_arch_set_memory_region(kvm, mem, old, user_alloc);
813 	if (r) {
814 		spin_lock(&kvm->mmu_lock);
815 		*memslot = old;
816 		spin_unlock(&kvm->mmu_lock);
817 		goto out_free;
818 	}
819 
820 	kvm_free_physmem_slot(&old, &new);
821 #ifdef CONFIG_DMAR
822 	/* map the pages in iommu page table */
823 	r = kvm_iommu_map_pages(kvm, base_gfn, npages);
824 	if (r)
825 		goto out;
826 #endif
827 	return 0;
828 
829 out_free:
830 	kvm_free_physmem_slot(&new, &old);
831 out:
832 	return r;
833 
834 }
835 EXPORT_SYMBOL_GPL(__kvm_set_memory_region);
836 
837 int kvm_set_memory_region(struct kvm *kvm,
838 			  struct kvm_userspace_memory_region *mem,
839 			  int user_alloc)
840 {
841 	int r;
842 
843 	down_write(&kvm->slots_lock);
844 	r = __kvm_set_memory_region(kvm, mem, user_alloc);
845 	up_write(&kvm->slots_lock);
846 	return r;
847 }
848 EXPORT_SYMBOL_GPL(kvm_set_memory_region);
849 
850 int kvm_vm_ioctl_set_memory_region(struct kvm *kvm,
851 				   struct
852 				   kvm_userspace_memory_region *mem,
853 				   int user_alloc)
854 {
855 	if (mem->slot >= KVM_MEMORY_SLOTS)
856 		return -EINVAL;
857 	return kvm_set_memory_region(kvm, mem, user_alloc);
858 }
859 
860 int kvm_get_dirty_log(struct kvm *kvm,
861 			struct kvm_dirty_log *log, int *is_dirty)
862 {
863 	struct kvm_memory_slot *memslot;
864 	int r, i;
865 	int n;
866 	unsigned long any = 0;
867 
868 	r = -EINVAL;
869 	if (log->slot >= KVM_MEMORY_SLOTS)
870 		goto out;
871 
872 	memslot = &kvm->memslots[log->slot];
873 	r = -ENOENT;
874 	if (!memslot->dirty_bitmap)
875 		goto out;
876 
877 	n = ALIGN(memslot->npages, BITS_PER_LONG) / 8;
878 
879 	for (i = 0; !any && i < n/sizeof(long); ++i)
880 		any = memslot->dirty_bitmap[i];
881 
882 	r = -EFAULT;
883 	if (copy_to_user(log->dirty_bitmap, memslot->dirty_bitmap, n))
884 		goto out;
885 
886 	if (any)
887 		*is_dirty = 1;
888 
889 	r = 0;
890 out:
891 	return r;
892 }
893 
894 int is_error_page(struct page *page)
895 {
896 	return page == bad_page;
897 }
898 EXPORT_SYMBOL_GPL(is_error_page);
899 
900 int is_error_pfn(pfn_t pfn)
901 {
902 	return pfn == bad_pfn;
903 }
904 EXPORT_SYMBOL_GPL(is_error_pfn);
905 
906 static inline unsigned long bad_hva(void)
907 {
908 	return PAGE_OFFSET;
909 }
910 
911 int kvm_is_error_hva(unsigned long addr)
912 {
913 	return addr == bad_hva();
914 }
915 EXPORT_SYMBOL_GPL(kvm_is_error_hva);
916 
917 static struct kvm_memory_slot *__gfn_to_memslot(struct kvm *kvm, gfn_t gfn)
918 {
919 	int i;
920 
921 	for (i = 0; i < kvm->nmemslots; ++i) {
922 		struct kvm_memory_slot *memslot = &kvm->memslots[i];
923 
924 		if (gfn >= memslot->base_gfn
925 		    && gfn < memslot->base_gfn + memslot->npages)
926 			return memslot;
927 	}
928 	return NULL;
929 }
930 
931 struct kvm_memory_slot *gfn_to_memslot(struct kvm *kvm, gfn_t gfn)
932 {
933 	gfn = unalias_gfn(kvm, gfn);
934 	return __gfn_to_memslot(kvm, gfn);
935 }
936 
937 int kvm_is_visible_gfn(struct kvm *kvm, gfn_t gfn)
938 {
939 	int i;
940 
941 	gfn = unalias_gfn(kvm, gfn);
942 	for (i = 0; i < KVM_MEMORY_SLOTS; ++i) {
943 		struct kvm_memory_slot *memslot = &kvm->memslots[i];
944 
945 		if (gfn >= memslot->base_gfn
946 		    && gfn < memslot->base_gfn + memslot->npages)
947 			return 1;
948 	}
949 	return 0;
950 }
951 EXPORT_SYMBOL_GPL(kvm_is_visible_gfn);
952 
953 unsigned long gfn_to_hva(struct kvm *kvm, gfn_t gfn)
954 {
955 	struct kvm_memory_slot *slot;
956 
957 	gfn = unalias_gfn(kvm, gfn);
958 	slot = __gfn_to_memslot(kvm, gfn);
959 	if (!slot)
960 		return bad_hva();
961 	return (slot->userspace_addr + (gfn - slot->base_gfn) * PAGE_SIZE);
962 }
963 EXPORT_SYMBOL_GPL(gfn_to_hva);
964 
965 pfn_t gfn_to_pfn(struct kvm *kvm, gfn_t gfn)
966 {
967 	struct page *page[1];
968 	unsigned long addr;
969 	int npages;
970 	pfn_t pfn;
971 
972 	might_sleep();
973 
974 	addr = gfn_to_hva(kvm, gfn);
975 	if (kvm_is_error_hva(addr)) {
976 		get_page(bad_page);
977 		return page_to_pfn(bad_page);
978 	}
979 
980 	npages = get_user_pages_fast(addr, 1, 1, page);
981 
982 	if (unlikely(npages != 1)) {
983 		struct vm_area_struct *vma;
984 
985 		down_read(&current->mm->mmap_sem);
986 		vma = find_vma(current->mm, addr);
987 
988 		if (vma == NULL || addr < vma->vm_start ||
989 		    !(vma->vm_flags & VM_PFNMAP)) {
990 			up_read(&current->mm->mmap_sem);
991 			get_page(bad_page);
992 			return page_to_pfn(bad_page);
993 		}
994 
995 		pfn = ((addr - vma->vm_start) >> PAGE_SHIFT) + vma->vm_pgoff;
996 		up_read(&current->mm->mmap_sem);
997 		BUG_ON(!kvm_is_mmio_pfn(pfn));
998 	} else
999 		pfn = page_to_pfn(page[0]);
1000 
1001 	return pfn;
1002 }
1003 
1004 EXPORT_SYMBOL_GPL(gfn_to_pfn);
1005 
1006 struct page *gfn_to_page(struct kvm *kvm, gfn_t gfn)
1007 {
1008 	pfn_t pfn;
1009 
1010 	pfn = gfn_to_pfn(kvm, gfn);
1011 	if (!kvm_is_mmio_pfn(pfn))
1012 		return pfn_to_page(pfn);
1013 
1014 	WARN_ON(kvm_is_mmio_pfn(pfn));
1015 
1016 	get_page(bad_page);
1017 	return bad_page;
1018 }
1019 
1020 EXPORT_SYMBOL_GPL(gfn_to_page);
1021 
1022 void kvm_release_page_clean(struct page *page)
1023 {
1024 	kvm_release_pfn_clean(page_to_pfn(page));
1025 }
1026 EXPORT_SYMBOL_GPL(kvm_release_page_clean);
1027 
1028 void kvm_release_pfn_clean(pfn_t pfn)
1029 {
1030 	if (!kvm_is_mmio_pfn(pfn))
1031 		put_page(pfn_to_page(pfn));
1032 }
1033 EXPORT_SYMBOL_GPL(kvm_release_pfn_clean);
1034 
1035 void kvm_release_page_dirty(struct page *page)
1036 {
1037 	kvm_release_pfn_dirty(page_to_pfn(page));
1038 }
1039 EXPORT_SYMBOL_GPL(kvm_release_page_dirty);
1040 
1041 void kvm_release_pfn_dirty(pfn_t pfn)
1042 {
1043 	kvm_set_pfn_dirty(pfn);
1044 	kvm_release_pfn_clean(pfn);
1045 }
1046 EXPORT_SYMBOL_GPL(kvm_release_pfn_dirty);
1047 
1048 void kvm_set_page_dirty(struct page *page)
1049 {
1050 	kvm_set_pfn_dirty(page_to_pfn(page));
1051 }
1052 EXPORT_SYMBOL_GPL(kvm_set_page_dirty);
1053 
1054 void kvm_set_pfn_dirty(pfn_t pfn)
1055 {
1056 	if (!kvm_is_mmio_pfn(pfn)) {
1057 		struct page *page = pfn_to_page(pfn);
1058 		if (!PageReserved(page))
1059 			SetPageDirty(page);
1060 	}
1061 }
1062 EXPORT_SYMBOL_GPL(kvm_set_pfn_dirty);
1063 
1064 void kvm_set_pfn_accessed(pfn_t pfn)
1065 {
1066 	if (!kvm_is_mmio_pfn(pfn))
1067 		mark_page_accessed(pfn_to_page(pfn));
1068 }
1069 EXPORT_SYMBOL_GPL(kvm_set_pfn_accessed);
1070 
1071 void kvm_get_pfn(pfn_t pfn)
1072 {
1073 	if (!kvm_is_mmio_pfn(pfn))
1074 		get_page(pfn_to_page(pfn));
1075 }
1076 EXPORT_SYMBOL_GPL(kvm_get_pfn);
1077 
1078 static int next_segment(unsigned long len, int offset)
1079 {
1080 	if (len > PAGE_SIZE - offset)
1081 		return PAGE_SIZE - offset;
1082 	else
1083 		return len;
1084 }
1085 
1086 int kvm_read_guest_page(struct kvm *kvm, gfn_t gfn, void *data, int offset,
1087 			int len)
1088 {
1089 	int r;
1090 	unsigned long addr;
1091 
1092 	addr = gfn_to_hva(kvm, gfn);
1093 	if (kvm_is_error_hva(addr))
1094 		return -EFAULT;
1095 	r = copy_from_user(data, (void __user *)addr + offset, len);
1096 	if (r)
1097 		return -EFAULT;
1098 	return 0;
1099 }
1100 EXPORT_SYMBOL_GPL(kvm_read_guest_page);
1101 
1102 int kvm_read_guest(struct kvm *kvm, gpa_t gpa, void *data, unsigned long len)
1103 {
1104 	gfn_t gfn = gpa >> PAGE_SHIFT;
1105 	int seg;
1106 	int offset = offset_in_page(gpa);
1107 	int ret;
1108 
1109 	while ((seg = next_segment(len, offset)) != 0) {
1110 		ret = kvm_read_guest_page(kvm, gfn, data, offset, seg);
1111 		if (ret < 0)
1112 			return ret;
1113 		offset = 0;
1114 		len -= seg;
1115 		data += seg;
1116 		++gfn;
1117 	}
1118 	return 0;
1119 }
1120 EXPORT_SYMBOL_GPL(kvm_read_guest);
1121 
1122 int kvm_read_guest_atomic(struct kvm *kvm, gpa_t gpa, void *data,
1123 			  unsigned long len)
1124 {
1125 	int r;
1126 	unsigned long addr;
1127 	gfn_t gfn = gpa >> PAGE_SHIFT;
1128 	int offset = offset_in_page(gpa);
1129 
1130 	addr = gfn_to_hva(kvm, gfn);
1131 	if (kvm_is_error_hva(addr))
1132 		return -EFAULT;
1133 	pagefault_disable();
1134 	r = __copy_from_user_inatomic(data, (void __user *)addr + offset, len);
1135 	pagefault_enable();
1136 	if (r)
1137 		return -EFAULT;
1138 	return 0;
1139 }
1140 EXPORT_SYMBOL(kvm_read_guest_atomic);
1141 
1142 int kvm_write_guest_page(struct kvm *kvm, gfn_t gfn, const void *data,
1143 			 int offset, int len)
1144 {
1145 	int r;
1146 	unsigned long addr;
1147 
1148 	addr = gfn_to_hva(kvm, gfn);
1149 	if (kvm_is_error_hva(addr))
1150 		return -EFAULT;
1151 	r = copy_to_user((void __user *)addr + offset, data, len);
1152 	if (r)
1153 		return -EFAULT;
1154 	mark_page_dirty(kvm, gfn);
1155 	return 0;
1156 }
1157 EXPORT_SYMBOL_GPL(kvm_write_guest_page);
1158 
1159 int kvm_write_guest(struct kvm *kvm, gpa_t gpa, const void *data,
1160 		    unsigned long len)
1161 {
1162 	gfn_t gfn = gpa >> PAGE_SHIFT;
1163 	int seg;
1164 	int offset = offset_in_page(gpa);
1165 	int ret;
1166 
1167 	while ((seg = next_segment(len, offset)) != 0) {
1168 		ret = kvm_write_guest_page(kvm, gfn, data, offset, seg);
1169 		if (ret < 0)
1170 			return ret;
1171 		offset = 0;
1172 		len -= seg;
1173 		data += seg;
1174 		++gfn;
1175 	}
1176 	return 0;
1177 }
1178 
1179 int kvm_clear_guest_page(struct kvm *kvm, gfn_t gfn, int offset, int len)
1180 {
1181 	return kvm_write_guest_page(kvm, gfn, empty_zero_page, offset, len);
1182 }
1183 EXPORT_SYMBOL_GPL(kvm_clear_guest_page);
1184 
1185 int kvm_clear_guest(struct kvm *kvm, gpa_t gpa, unsigned long len)
1186 {
1187 	gfn_t gfn = gpa >> PAGE_SHIFT;
1188 	int seg;
1189 	int offset = offset_in_page(gpa);
1190 	int ret;
1191 
1192         while ((seg = next_segment(len, offset)) != 0) {
1193 		ret = kvm_clear_guest_page(kvm, gfn, offset, seg);
1194 		if (ret < 0)
1195 			return ret;
1196 		offset = 0;
1197 		len -= seg;
1198 		++gfn;
1199 	}
1200 	return 0;
1201 }
1202 EXPORT_SYMBOL_GPL(kvm_clear_guest);
1203 
1204 void mark_page_dirty(struct kvm *kvm, gfn_t gfn)
1205 {
1206 	struct kvm_memory_slot *memslot;
1207 
1208 	gfn = unalias_gfn(kvm, gfn);
1209 	memslot = __gfn_to_memslot(kvm, gfn);
1210 	if (memslot && memslot->dirty_bitmap) {
1211 		unsigned long rel_gfn = gfn - memslot->base_gfn;
1212 
1213 		/* avoid RMW */
1214 		if (!test_bit(rel_gfn, memslot->dirty_bitmap))
1215 			set_bit(rel_gfn, memslot->dirty_bitmap);
1216 	}
1217 }
1218 
1219 /*
1220  * The vCPU has executed a HLT instruction with in-kernel mode enabled.
1221  */
1222 void kvm_vcpu_block(struct kvm_vcpu *vcpu)
1223 {
1224 	DEFINE_WAIT(wait);
1225 
1226 	for (;;) {
1227 		prepare_to_wait(&vcpu->wq, &wait, TASK_INTERRUPTIBLE);
1228 
1229 		if (kvm_cpu_has_interrupt(vcpu) ||
1230 		    kvm_cpu_has_pending_timer(vcpu) ||
1231 		    kvm_arch_vcpu_runnable(vcpu)) {
1232 			set_bit(KVM_REQ_UNHALT, &vcpu->requests);
1233 			break;
1234 		}
1235 		if (signal_pending(current))
1236 			break;
1237 
1238 		vcpu_put(vcpu);
1239 		schedule();
1240 		vcpu_load(vcpu);
1241 	}
1242 
1243 	finish_wait(&vcpu->wq, &wait);
1244 }
1245 
1246 void kvm_resched(struct kvm_vcpu *vcpu)
1247 {
1248 	if (!need_resched())
1249 		return;
1250 	cond_resched();
1251 }
1252 EXPORT_SYMBOL_GPL(kvm_resched);
1253 
1254 static int kvm_vcpu_fault(struct vm_area_struct *vma, struct vm_fault *vmf)
1255 {
1256 	struct kvm_vcpu *vcpu = vma->vm_file->private_data;
1257 	struct page *page;
1258 
1259 	if (vmf->pgoff == 0)
1260 		page = virt_to_page(vcpu->run);
1261 #ifdef CONFIG_X86
1262 	else if (vmf->pgoff == KVM_PIO_PAGE_OFFSET)
1263 		page = virt_to_page(vcpu->arch.pio_data);
1264 #endif
1265 #ifdef KVM_COALESCED_MMIO_PAGE_OFFSET
1266 	else if (vmf->pgoff == KVM_COALESCED_MMIO_PAGE_OFFSET)
1267 		page = virt_to_page(vcpu->kvm->coalesced_mmio_ring);
1268 #endif
1269 	else
1270 		return VM_FAULT_SIGBUS;
1271 	get_page(page);
1272 	vmf->page = page;
1273 	return 0;
1274 }
1275 
1276 static struct vm_operations_struct kvm_vcpu_vm_ops = {
1277 	.fault = kvm_vcpu_fault,
1278 };
1279 
1280 static int kvm_vcpu_mmap(struct file *file, struct vm_area_struct *vma)
1281 {
1282 	vma->vm_ops = &kvm_vcpu_vm_ops;
1283 	return 0;
1284 }
1285 
1286 static int kvm_vcpu_release(struct inode *inode, struct file *filp)
1287 {
1288 	struct kvm_vcpu *vcpu = filp->private_data;
1289 
1290 	kvm_put_kvm(vcpu->kvm);
1291 	return 0;
1292 }
1293 
1294 static const struct file_operations kvm_vcpu_fops = {
1295 	.release        = kvm_vcpu_release,
1296 	.unlocked_ioctl = kvm_vcpu_ioctl,
1297 	.compat_ioctl   = kvm_vcpu_ioctl,
1298 	.mmap           = kvm_vcpu_mmap,
1299 };
1300 
1301 /*
1302  * Allocates an inode for the vcpu.
1303  */
1304 static int create_vcpu_fd(struct kvm_vcpu *vcpu)
1305 {
1306 	int fd = anon_inode_getfd("kvm-vcpu", &kvm_vcpu_fops, vcpu, 0);
1307 	if (fd < 0)
1308 		kvm_put_kvm(vcpu->kvm);
1309 	return fd;
1310 }
1311 
1312 /*
1313  * Creates some virtual cpus.  Good luck creating more than one.
1314  */
1315 static int kvm_vm_ioctl_create_vcpu(struct kvm *kvm, int n)
1316 {
1317 	int r;
1318 	struct kvm_vcpu *vcpu;
1319 
1320 	if (!valid_vcpu(n))
1321 		return -EINVAL;
1322 
1323 	vcpu = kvm_arch_vcpu_create(kvm, n);
1324 	if (IS_ERR(vcpu))
1325 		return PTR_ERR(vcpu);
1326 
1327 	preempt_notifier_init(&vcpu->preempt_notifier, &kvm_preempt_ops);
1328 
1329 	r = kvm_arch_vcpu_setup(vcpu);
1330 	if (r)
1331 		return r;
1332 
1333 	mutex_lock(&kvm->lock);
1334 	if (kvm->vcpus[n]) {
1335 		r = -EEXIST;
1336 		goto vcpu_destroy;
1337 	}
1338 	kvm->vcpus[n] = vcpu;
1339 	mutex_unlock(&kvm->lock);
1340 
1341 	/* Now it's all set up, let userspace reach it */
1342 	kvm_get_kvm(kvm);
1343 	r = create_vcpu_fd(vcpu);
1344 	if (r < 0)
1345 		goto unlink;
1346 	return r;
1347 
1348 unlink:
1349 	mutex_lock(&kvm->lock);
1350 	kvm->vcpus[n] = NULL;
1351 vcpu_destroy:
1352 	mutex_unlock(&kvm->lock);
1353 	kvm_arch_vcpu_destroy(vcpu);
1354 	return r;
1355 }
1356 
1357 static int kvm_vcpu_ioctl_set_sigmask(struct kvm_vcpu *vcpu, sigset_t *sigset)
1358 {
1359 	if (sigset) {
1360 		sigdelsetmask(sigset, sigmask(SIGKILL)|sigmask(SIGSTOP));
1361 		vcpu->sigset_active = 1;
1362 		vcpu->sigset = *sigset;
1363 	} else
1364 		vcpu->sigset_active = 0;
1365 	return 0;
1366 }
1367 
1368 static long kvm_vcpu_ioctl(struct file *filp,
1369 			   unsigned int ioctl, unsigned long arg)
1370 {
1371 	struct kvm_vcpu *vcpu = filp->private_data;
1372 	void __user *argp = (void __user *)arg;
1373 	int r;
1374 	struct kvm_fpu *fpu = NULL;
1375 	struct kvm_sregs *kvm_sregs = NULL;
1376 
1377 	if (vcpu->kvm->mm != current->mm)
1378 		return -EIO;
1379 	switch (ioctl) {
1380 	case KVM_RUN:
1381 		r = -EINVAL;
1382 		if (arg)
1383 			goto out;
1384 		r = kvm_arch_vcpu_ioctl_run(vcpu, vcpu->run);
1385 		break;
1386 	case KVM_GET_REGS: {
1387 		struct kvm_regs *kvm_regs;
1388 
1389 		r = -ENOMEM;
1390 		kvm_regs = kzalloc(sizeof(struct kvm_regs), GFP_KERNEL);
1391 		if (!kvm_regs)
1392 			goto out;
1393 		r = kvm_arch_vcpu_ioctl_get_regs(vcpu, kvm_regs);
1394 		if (r)
1395 			goto out_free1;
1396 		r = -EFAULT;
1397 		if (copy_to_user(argp, kvm_regs, sizeof(struct kvm_regs)))
1398 			goto out_free1;
1399 		r = 0;
1400 out_free1:
1401 		kfree(kvm_regs);
1402 		break;
1403 	}
1404 	case KVM_SET_REGS: {
1405 		struct kvm_regs *kvm_regs;
1406 
1407 		r = -ENOMEM;
1408 		kvm_regs = kzalloc(sizeof(struct kvm_regs), GFP_KERNEL);
1409 		if (!kvm_regs)
1410 			goto out;
1411 		r = -EFAULT;
1412 		if (copy_from_user(kvm_regs, argp, sizeof(struct kvm_regs)))
1413 			goto out_free2;
1414 		r = kvm_arch_vcpu_ioctl_set_regs(vcpu, kvm_regs);
1415 		if (r)
1416 			goto out_free2;
1417 		r = 0;
1418 out_free2:
1419 		kfree(kvm_regs);
1420 		break;
1421 	}
1422 	case KVM_GET_SREGS: {
1423 		kvm_sregs = kzalloc(sizeof(struct kvm_sregs), GFP_KERNEL);
1424 		r = -ENOMEM;
1425 		if (!kvm_sregs)
1426 			goto out;
1427 		r = kvm_arch_vcpu_ioctl_get_sregs(vcpu, kvm_sregs);
1428 		if (r)
1429 			goto out;
1430 		r = -EFAULT;
1431 		if (copy_to_user(argp, kvm_sregs, sizeof(struct kvm_sregs)))
1432 			goto out;
1433 		r = 0;
1434 		break;
1435 	}
1436 	case KVM_SET_SREGS: {
1437 		kvm_sregs = kmalloc(sizeof(struct kvm_sregs), GFP_KERNEL);
1438 		r = -ENOMEM;
1439 		if (!kvm_sregs)
1440 			goto out;
1441 		r = -EFAULT;
1442 		if (copy_from_user(kvm_sregs, argp, sizeof(struct kvm_sregs)))
1443 			goto out;
1444 		r = kvm_arch_vcpu_ioctl_set_sregs(vcpu, kvm_sregs);
1445 		if (r)
1446 			goto out;
1447 		r = 0;
1448 		break;
1449 	}
1450 	case KVM_GET_MP_STATE: {
1451 		struct kvm_mp_state mp_state;
1452 
1453 		r = kvm_arch_vcpu_ioctl_get_mpstate(vcpu, &mp_state);
1454 		if (r)
1455 			goto out;
1456 		r = -EFAULT;
1457 		if (copy_to_user(argp, &mp_state, sizeof mp_state))
1458 			goto out;
1459 		r = 0;
1460 		break;
1461 	}
1462 	case KVM_SET_MP_STATE: {
1463 		struct kvm_mp_state mp_state;
1464 
1465 		r = -EFAULT;
1466 		if (copy_from_user(&mp_state, argp, sizeof mp_state))
1467 			goto out;
1468 		r = kvm_arch_vcpu_ioctl_set_mpstate(vcpu, &mp_state);
1469 		if (r)
1470 			goto out;
1471 		r = 0;
1472 		break;
1473 	}
1474 	case KVM_TRANSLATE: {
1475 		struct kvm_translation tr;
1476 
1477 		r = -EFAULT;
1478 		if (copy_from_user(&tr, argp, sizeof tr))
1479 			goto out;
1480 		r = kvm_arch_vcpu_ioctl_translate(vcpu, &tr);
1481 		if (r)
1482 			goto out;
1483 		r = -EFAULT;
1484 		if (copy_to_user(argp, &tr, sizeof tr))
1485 			goto out;
1486 		r = 0;
1487 		break;
1488 	}
1489 	case KVM_DEBUG_GUEST: {
1490 		struct kvm_debug_guest dbg;
1491 
1492 		r = -EFAULT;
1493 		if (copy_from_user(&dbg, argp, sizeof dbg))
1494 			goto out;
1495 		r = kvm_arch_vcpu_ioctl_debug_guest(vcpu, &dbg);
1496 		if (r)
1497 			goto out;
1498 		r = 0;
1499 		break;
1500 	}
1501 	case KVM_SET_SIGNAL_MASK: {
1502 		struct kvm_signal_mask __user *sigmask_arg = argp;
1503 		struct kvm_signal_mask kvm_sigmask;
1504 		sigset_t sigset, *p;
1505 
1506 		p = NULL;
1507 		if (argp) {
1508 			r = -EFAULT;
1509 			if (copy_from_user(&kvm_sigmask, argp,
1510 					   sizeof kvm_sigmask))
1511 				goto out;
1512 			r = -EINVAL;
1513 			if (kvm_sigmask.len != sizeof sigset)
1514 				goto out;
1515 			r = -EFAULT;
1516 			if (copy_from_user(&sigset, sigmask_arg->sigset,
1517 					   sizeof sigset))
1518 				goto out;
1519 			p = &sigset;
1520 		}
1521 		r = kvm_vcpu_ioctl_set_sigmask(vcpu, &sigset);
1522 		break;
1523 	}
1524 	case KVM_GET_FPU: {
1525 		fpu = kzalloc(sizeof(struct kvm_fpu), GFP_KERNEL);
1526 		r = -ENOMEM;
1527 		if (!fpu)
1528 			goto out;
1529 		r = kvm_arch_vcpu_ioctl_get_fpu(vcpu, fpu);
1530 		if (r)
1531 			goto out;
1532 		r = -EFAULT;
1533 		if (copy_to_user(argp, fpu, sizeof(struct kvm_fpu)))
1534 			goto out;
1535 		r = 0;
1536 		break;
1537 	}
1538 	case KVM_SET_FPU: {
1539 		fpu = kmalloc(sizeof(struct kvm_fpu), GFP_KERNEL);
1540 		r = -ENOMEM;
1541 		if (!fpu)
1542 			goto out;
1543 		r = -EFAULT;
1544 		if (copy_from_user(fpu, argp, sizeof(struct kvm_fpu)))
1545 			goto out;
1546 		r = kvm_arch_vcpu_ioctl_set_fpu(vcpu, fpu);
1547 		if (r)
1548 			goto out;
1549 		r = 0;
1550 		break;
1551 	}
1552 	default:
1553 		r = kvm_arch_vcpu_ioctl(filp, ioctl, arg);
1554 	}
1555 out:
1556 	kfree(fpu);
1557 	kfree(kvm_sregs);
1558 	return r;
1559 }
1560 
1561 static long kvm_vm_ioctl(struct file *filp,
1562 			   unsigned int ioctl, unsigned long arg)
1563 {
1564 	struct kvm *kvm = filp->private_data;
1565 	void __user *argp = (void __user *)arg;
1566 	int r;
1567 
1568 	if (kvm->mm != current->mm)
1569 		return -EIO;
1570 	switch (ioctl) {
1571 	case KVM_CREATE_VCPU:
1572 		r = kvm_vm_ioctl_create_vcpu(kvm, arg);
1573 		if (r < 0)
1574 			goto out;
1575 		break;
1576 	case KVM_SET_USER_MEMORY_REGION: {
1577 		struct kvm_userspace_memory_region kvm_userspace_mem;
1578 
1579 		r = -EFAULT;
1580 		if (copy_from_user(&kvm_userspace_mem, argp,
1581 						sizeof kvm_userspace_mem))
1582 			goto out;
1583 
1584 		r = kvm_vm_ioctl_set_memory_region(kvm, &kvm_userspace_mem, 1);
1585 		if (r)
1586 			goto out;
1587 		break;
1588 	}
1589 	case KVM_GET_DIRTY_LOG: {
1590 		struct kvm_dirty_log log;
1591 
1592 		r = -EFAULT;
1593 		if (copy_from_user(&log, argp, sizeof log))
1594 			goto out;
1595 		r = kvm_vm_ioctl_get_dirty_log(kvm, &log);
1596 		if (r)
1597 			goto out;
1598 		break;
1599 	}
1600 #ifdef KVM_COALESCED_MMIO_PAGE_OFFSET
1601 	case KVM_REGISTER_COALESCED_MMIO: {
1602 		struct kvm_coalesced_mmio_zone zone;
1603 		r = -EFAULT;
1604 		if (copy_from_user(&zone, argp, sizeof zone))
1605 			goto out;
1606 		r = -ENXIO;
1607 		r = kvm_vm_ioctl_register_coalesced_mmio(kvm, &zone);
1608 		if (r)
1609 			goto out;
1610 		r = 0;
1611 		break;
1612 	}
1613 	case KVM_UNREGISTER_COALESCED_MMIO: {
1614 		struct kvm_coalesced_mmio_zone zone;
1615 		r = -EFAULT;
1616 		if (copy_from_user(&zone, argp, sizeof zone))
1617 			goto out;
1618 		r = -ENXIO;
1619 		r = kvm_vm_ioctl_unregister_coalesced_mmio(kvm, &zone);
1620 		if (r)
1621 			goto out;
1622 		r = 0;
1623 		break;
1624 	}
1625 #endif
1626 #ifdef KVM_CAP_DEVICE_ASSIGNMENT
1627 	case KVM_ASSIGN_PCI_DEVICE: {
1628 		struct kvm_assigned_pci_dev assigned_dev;
1629 
1630 		r = -EFAULT;
1631 		if (copy_from_user(&assigned_dev, argp, sizeof assigned_dev))
1632 			goto out;
1633 		r = kvm_vm_ioctl_assign_device(kvm, &assigned_dev);
1634 		if (r)
1635 			goto out;
1636 		break;
1637 	}
1638 	case KVM_ASSIGN_IRQ: {
1639 		struct kvm_assigned_irq assigned_irq;
1640 
1641 		r = -EFAULT;
1642 		if (copy_from_user(&assigned_irq, argp, sizeof assigned_irq))
1643 			goto out;
1644 		r = kvm_vm_ioctl_assign_irq(kvm, &assigned_irq);
1645 		if (r)
1646 			goto out;
1647 		break;
1648 	}
1649 #endif
1650 	default:
1651 		r = kvm_arch_vm_ioctl(filp, ioctl, arg);
1652 	}
1653 out:
1654 	return r;
1655 }
1656 
1657 static int kvm_vm_fault(struct vm_area_struct *vma, struct vm_fault *vmf)
1658 {
1659 	struct page *page[1];
1660 	unsigned long addr;
1661 	int npages;
1662 	gfn_t gfn = vmf->pgoff;
1663 	struct kvm *kvm = vma->vm_file->private_data;
1664 
1665 	addr = gfn_to_hva(kvm, gfn);
1666 	if (kvm_is_error_hva(addr))
1667 		return VM_FAULT_SIGBUS;
1668 
1669 	npages = get_user_pages(current, current->mm, addr, 1, 1, 0, page,
1670 				NULL);
1671 	if (unlikely(npages != 1))
1672 		return VM_FAULT_SIGBUS;
1673 
1674 	vmf->page = page[0];
1675 	return 0;
1676 }
1677 
1678 static struct vm_operations_struct kvm_vm_vm_ops = {
1679 	.fault = kvm_vm_fault,
1680 };
1681 
1682 static int kvm_vm_mmap(struct file *file, struct vm_area_struct *vma)
1683 {
1684 	vma->vm_ops = &kvm_vm_vm_ops;
1685 	return 0;
1686 }
1687 
1688 static const struct file_operations kvm_vm_fops = {
1689 	.release        = kvm_vm_release,
1690 	.unlocked_ioctl = kvm_vm_ioctl,
1691 	.compat_ioctl   = kvm_vm_ioctl,
1692 	.mmap           = kvm_vm_mmap,
1693 };
1694 
1695 static int kvm_dev_ioctl_create_vm(void)
1696 {
1697 	int fd;
1698 	struct kvm *kvm;
1699 
1700 	kvm = kvm_create_vm();
1701 	if (IS_ERR(kvm))
1702 		return PTR_ERR(kvm);
1703 	fd = anon_inode_getfd("kvm-vm", &kvm_vm_fops, kvm, 0);
1704 	if (fd < 0)
1705 		kvm_put_kvm(kvm);
1706 
1707 	return fd;
1708 }
1709 
1710 static long kvm_dev_ioctl(struct file *filp,
1711 			  unsigned int ioctl, unsigned long arg)
1712 {
1713 	long r = -EINVAL;
1714 
1715 	switch (ioctl) {
1716 	case KVM_GET_API_VERSION:
1717 		r = -EINVAL;
1718 		if (arg)
1719 			goto out;
1720 		r = KVM_API_VERSION;
1721 		break;
1722 	case KVM_CREATE_VM:
1723 		r = -EINVAL;
1724 		if (arg)
1725 			goto out;
1726 		r = kvm_dev_ioctl_create_vm();
1727 		break;
1728 	case KVM_CHECK_EXTENSION:
1729 		r = kvm_dev_ioctl_check_extension(arg);
1730 		break;
1731 	case KVM_GET_VCPU_MMAP_SIZE:
1732 		r = -EINVAL;
1733 		if (arg)
1734 			goto out;
1735 		r = PAGE_SIZE;     /* struct kvm_run */
1736 #ifdef CONFIG_X86
1737 		r += PAGE_SIZE;    /* pio data page */
1738 #endif
1739 #ifdef KVM_COALESCED_MMIO_PAGE_OFFSET
1740 		r += PAGE_SIZE;    /* coalesced mmio ring page */
1741 #endif
1742 		break;
1743 	case KVM_TRACE_ENABLE:
1744 	case KVM_TRACE_PAUSE:
1745 	case KVM_TRACE_DISABLE:
1746 		r = kvm_trace_ioctl(ioctl, arg);
1747 		break;
1748 	default:
1749 		return kvm_arch_dev_ioctl(filp, ioctl, arg);
1750 	}
1751 out:
1752 	return r;
1753 }
1754 
1755 static struct file_operations kvm_chardev_ops = {
1756 	.unlocked_ioctl = kvm_dev_ioctl,
1757 	.compat_ioctl   = kvm_dev_ioctl,
1758 };
1759 
1760 static struct miscdevice kvm_dev = {
1761 	KVM_MINOR,
1762 	"kvm",
1763 	&kvm_chardev_ops,
1764 };
1765 
1766 static void hardware_enable(void *junk)
1767 {
1768 	int cpu = raw_smp_processor_id();
1769 
1770 	if (cpu_isset(cpu, cpus_hardware_enabled))
1771 		return;
1772 	cpu_set(cpu, cpus_hardware_enabled);
1773 	kvm_arch_hardware_enable(NULL);
1774 }
1775 
1776 static void hardware_disable(void *junk)
1777 {
1778 	int cpu = raw_smp_processor_id();
1779 
1780 	if (!cpu_isset(cpu, cpus_hardware_enabled))
1781 		return;
1782 	cpu_clear(cpu, cpus_hardware_enabled);
1783 	kvm_arch_hardware_disable(NULL);
1784 }
1785 
1786 static int kvm_cpu_hotplug(struct notifier_block *notifier, unsigned long val,
1787 			   void *v)
1788 {
1789 	int cpu = (long)v;
1790 
1791 	val &= ~CPU_TASKS_FROZEN;
1792 	switch (val) {
1793 	case CPU_DYING:
1794 		printk(KERN_INFO "kvm: disabling virtualization on CPU%d\n",
1795 		       cpu);
1796 		hardware_disable(NULL);
1797 		break;
1798 	case CPU_UP_CANCELED:
1799 		printk(KERN_INFO "kvm: disabling virtualization on CPU%d\n",
1800 		       cpu);
1801 		smp_call_function_single(cpu, hardware_disable, NULL, 1);
1802 		break;
1803 	case CPU_ONLINE:
1804 		printk(KERN_INFO "kvm: enabling virtualization on CPU%d\n",
1805 		       cpu);
1806 		smp_call_function_single(cpu, hardware_enable, NULL, 1);
1807 		break;
1808 	}
1809 	return NOTIFY_OK;
1810 }
1811 
1812 
1813 asmlinkage void kvm_handle_fault_on_reboot(void)
1814 {
1815 	if (kvm_rebooting)
1816 		/* spin while reset goes on */
1817 		while (true)
1818 			;
1819 	/* Fault while not rebooting.  We want the trace. */
1820 	BUG();
1821 }
1822 EXPORT_SYMBOL_GPL(kvm_handle_fault_on_reboot);
1823 
1824 static int kvm_reboot(struct notifier_block *notifier, unsigned long val,
1825 		      void *v)
1826 {
1827 	if (val == SYS_RESTART) {
1828 		/*
1829 		 * Some (well, at least mine) BIOSes hang on reboot if
1830 		 * in vmx root mode.
1831 		 */
1832 		printk(KERN_INFO "kvm: exiting hardware virtualization\n");
1833 		kvm_rebooting = true;
1834 		on_each_cpu(hardware_disable, NULL, 1);
1835 	}
1836 	return NOTIFY_OK;
1837 }
1838 
1839 static struct notifier_block kvm_reboot_notifier = {
1840 	.notifier_call = kvm_reboot,
1841 	.priority = 0,
1842 };
1843 
1844 void kvm_io_bus_init(struct kvm_io_bus *bus)
1845 {
1846 	memset(bus, 0, sizeof(*bus));
1847 }
1848 
1849 void kvm_io_bus_destroy(struct kvm_io_bus *bus)
1850 {
1851 	int i;
1852 
1853 	for (i = 0; i < bus->dev_count; i++) {
1854 		struct kvm_io_device *pos = bus->devs[i];
1855 
1856 		kvm_iodevice_destructor(pos);
1857 	}
1858 }
1859 
1860 struct kvm_io_device *kvm_io_bus_find_dev(struct kvm_io_bus *bus,
1861 					  gpa_t addr, int len, int is_write)
1862 {
1863 	int i;
1864 
1865 	for (i = 0; i < bus->dev_count; i++) {
1866 		struct kvm_io_device *pos = bus->devs[i];
1867 
1868 		if (pos->in_range(pos, addr, len, is_write))
1869 			return pos;
1870 	}
1871 
1872 	return NULL;
1873 }
1874 
1875 void kvm_io_bus_register_dev(struct kvm_io_bus *bus, struct kvm_io_device *dev)
1876 {
1877 	BUG_ON(bus->dev_count > (NR_IOBUS_DEVS-1));
1878 
1879 	bus->devs[bus->dev_count++] = dev;
1880 }
1881 
1882 static struct notifier_block kvm_cpu_notifier = {
1883 	.notifier_call = kvm_cpu_hotplug,
1884 	.priority = 20, /* must be > scheduler priority */
1885 };
1886 
1887 static int vm_stat_get(void *_offset, u64 *val)
1888 {
1889 	unsigned offset = (long)_offset;
1890 	struct kvm *kvm;
1891 
1892 	*val = 0;
1893 	spin_lock(&kvm_lock);
1894 	list_for_each_entry(kvm, &vm_list, vm_list)
1895 		*val += *(u32 *)((void *)kvm + offset);
1896 	spin_unlock(&kvm_lock);
1897 	return 0;
1898 }
1899 
1900 DEFINE_SIMPLE_ATTRIBUTE(vm_stat_fops, vm_stat_get, NULL, "%llu\n");
1901 
1902 static int vcpu_stat_get(void *_offset, u64 *val)
1903 {
1904 	unsigned offset = (long)_offset;
1905 	struct kvm *kvm;
1906 	struct kvm_vcpu *vcpu;
1907 	int i;
1908 
1909 	*val = 0;
1910 	spin_lock(&kvm_lock);
1911 	list_for_each_entry(kvm, &vm_list, vm_list)
1912 		for (i = 0; i < KVM_MAX_VCPUS; ++i) {
1913 			vcpu = kvm->vcpus[i];
1914 			if (vcpu)
1915 				*val += *(u32 *)((void *)vcpu + offset);
1916 		}
1917 	spin_unlock(&kvm_lock);
1918 	return 0;
1919 }
1920 
1921 DEFINE_SIMPLE_ATTRIBUTE(vcpu_stat_fops, vcpu_stat_get, NULL, "%llu\n");
1922 
1923 static struct file_operations *stat_fops[] = {
1924 	[KVM_STAT_VCPU] = &vcpu_stat_fops,
1925 	[KVM_STAT_VM]   = &vm_stat_fops,
1926 };
1927 
1928 static void kvm_init_debug(void)
1929 {
1930 	struct kvm_stats_debugfs_item *p;
1931 
1932 	kvm_debugfs_dir = debugfs_create_dir("kvm", NULL);
1933 	for (p = debugfs_entries; p->name; ++p)
1934 		p->dentry = debugfs_create_file(p->name, 0444, kvm_debugfs_dir,
1935 						(void *)(long)p->offset,
1936 						stat_fops[p->kind]);
1937 }
1938 
1939 static void kvm_exit_debug(void)
1940 {
1941 	struct kvm_stats_debugfs_item *p;
1942 
1943 	for (p = debugfs_entries; p->name; ++p)
1944 		debugfs_remove(p->dentry);
1945 	debugfs_remove(kvm_debugfs_dir);
1946 }
1947 
1948 static int kvm_suspend(struct sys_device *dev, pm_message_t state)
1949 {
1950 	hardware_disable(NULL);
1951 	return 0;
1952 }
1953 
1954 static int kvm_resume(struct sys_device *dev)
1955 {
1956 	hardware_enable(NULL);
1957 	return 0;
1958 }
1959 
1960 static struct sysdev_class kvm_sysdev_class = {
1961 	.name = "kvm",
1962 	.suspend = kvm_suspend,
1963 	.resume = kvm_resume,
1964 };
1965 
1966 static struct sys_device kvm_sysdev = {
1967 	.id = 0,
1968 	.cls = &kvm_sysdev_class,
1969 };
1970 
1971 struct page *bad_page;
1972 pfn_t bad_pfn;
1973 
1974 static inline
1975 struct kvm_vcpu *preempt_notifier_to_vcpu(struct preempt_notifier *pn)
1976 {
1977 	return container_of(pn, struct kvm_vcpu, preempt_notifier);
1978 }
1979 
1980 static void kvm_sched_in(struct preempt_notifier *pn, int cpu)
1981 {
1982 	struct kvm_vcpu *vcpu = preempt_notifier_to_vcpu(pn);
1983 
1984 	kvm_arch_vcpu_load(vcpu, cpu);
1985 }
1986 
1987 static void kvm_sched_out(struct preempt_notifier *pn,
1988 			  struct task_struct *next)
1989 {
1990 	struct kvm_vcpu *vcpu = preempt_notifier_to_vcpu(pn);
1991 
1992 	kvm_arch_vcpu_put(vcpu);
1993 }
1994 
1995 int kvm_init(void *opaque, unsigned int vcpu_size,
1996 		  struct module *module)
1997 {
1998 	int r;
1999 	int cpu;
2000 
2001 	kvm_init_debug();
2002 
2003 	r = kvm_arch_init(opaque);
2004 	if (r)
2005 		goto out_fail;
2006 
2007 	bad_page = alloc_page(GFP_KERNEL | __GFP_ZERO);
2008 
2009 	if (bad_page == NULL) {
2010 		r = -ENOMEM;
2011 		goto out;
2012 	}
2013 
2014 	bad_pfn = page_to_pfn(bad_page);
2015 
2016 	r = kvm_arch_hardware_setup();
2017 	if (r < 0)
2018 		goto out_free_0;
2019 
2020 	for_each_online_cpu(cpu) {
2021 		smp_call_function_single(cpu,
2022 				kvm_arch_check_processor_compat,
2023 				&r, 1);
2024 		if (r < 0)
2025 			goto out_free_1;
2026 	}
2027 
2028 	on_each_cpu(hardware_enable, NULL, 1);
2029 	r = register_cpu_notifier(&kvm_cpu_notifier);
2030 	if (r)
2031 		goto out_free_2;
2032 	register_reboot_notifier(&kvm_reboot_notifier);
2033 
2034 	r = sysdev_class_register(&kvm_sysdev_class);
2035 	if (r)
2036 		goto out_free_3;
2037 
2038 	r = sysdev_register(&kvm_sysdev);
2039 	if (r)
2040 		goto out_free_4;
2041 
2042 	/* A kmem cache lets us meet the alignment requirements of fx_save. */
2043 	kvm_vcpu_cache = kmem_cache_create("kvm_vcpu", vcpu_size,
2044 					   __alignof__(struct kvm_vcpu),
2045 					   0, NULL);
2046 	if (!kvm_vcpu_cache) {
2047 		r = -ENOMEM;
2048 		goto out_free_5;
2049 	}
2050 
2051 	kvm_chardev_ops.owner = module;
2052 
2053 	r = misc_register(&kvm_dev);
2054 	if (r) {
2055 		printk(KERN_ERR "kvm: misc device register failed\n");
2056 		goto out_free;
2057 	}
2058 
2059 	kvm_preempt_ops.sched_in = kvm_sched_in;
2060 	kvm_preempt_ops.sched_out = kvm_sched_out;
2061 
2062 	return 0;
2063 
2064 out_free:
2065 	kmem_cache_destroy(kvm_vcpu_cache);
2066 out_free_5:
2067 	sysdev_unregister(&kvm_sysdev);
2068 out_free_4:
2069 	sysdev_class_unregister(&kvm_sysdev_class);
2070 out_free_3:
2071 	unregister_reboot_notifier(&kvm_reboot_notifier);
2072 	unregister_cpu_notifier(&kvm_cpu_notifier);
2073 out_free_2:
2074 	on_each_cpu(hardware_disable, NULL, 1);
2075 out_free_1:
2076 	kvm_arch_hardware_unsetup();
2077 out_free_0:
2078 	__free_page(bad_page);
2079 out:
2080 	kvm_arch_exit();
2081 	kvm_exit_debug();
2082 out_fail:
2083 	return r;
2084 }
2085 EXPORT_SYMBOL_GPL(kvm_init);
2086 
2087 void kvm_exit(void)
2088 {
2089 	kvm_trace_cleanup();
2090 	misc_deregister(&kvm_dev);
2091 	kmem_cache_destroy(kvm_vcpu_cache);
2092 	sysdev_unregister(&kvm_sysdev);
2093 	sysdev_class_unregister(&kvm_sysdev_class);
2094 	unregister_reboot_notifier(&kvm_reboot_notifier);
2095 	unregister_cpu_notifier(&kvm_cpu_notifier);
2096 	on_each_cpu(hardware_disable, NULL, 1);
2097 	kvm_arch_hardware_unsetup();
2098 	kvm_arch_exit();
2099 	kvm_exit_debug();
2100 	__free_page(bad_page);
2101 }
2102 EXPORT_SYMBOL_GPL(kvm_exit);
2103