xref: /linux/virt/kvm/kvm_main.c (revision dfc349402de8e95f6a42e8341e9ea193b718eee3)
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 #include <linux/bitops.h>
45 #include <linux/spinlock.h>
46 
47 #include <asm/processor.h>
48 #include <asm/io.h>
49 #include <asm/uaccess.h>
50 #include <asm/pgtable.h>
51 
52 #ifdef KVM_COALESCED_MMIO_PAGE_OFFSET
53 #include "coalesced_mmio.h"
54 #endif
55 
56 #ifdef KVM_CAP_DEVICE_ASSIGNMENT
57 #include <linux/pci.h>
58 #include <linux/interrupt.h>
59 #include "irq.h"
60 #endif
61 
62 #define CREATE_TRACE_POINTS
63 #include <trace/events/kvm.h>
64 
65 MODULE_AUTHOR("Qumranet");
66 MODULE_LICENSE("GPL");
67 
68 /*
69  * Ordering of locks:
70  *
71  * 		kvm->slots_lock --> kvm->lock --> kvm->irq_lock
72  */
73 
74 DEFINE_SPINLOCK(kvm_lock);
75 LIST_HEAD(vm_list);
76 
77 static cpumask_var_t cpus_hardware_enabled;
78 
79 struct kmem_cache *kvm_vcpu_cache;
80 EXPORT_SYMBOL_GPL(kvm_vcpu_cache);
81 
82 static __read_mostly struct preempt_ops kvm_preempt_ops;
83 
84 struct dentry *kvm_debugfs_dir;
85 
86 static long kvm_vcpu_ioctl(struct file *file, unsigned int ioctl,
87 			   unsigned long arg);
88 
89 static bool kvm_rebooting;
90 
91 static bool largepages_enabled = true;
92 
93 #ifdef KVM_CAP_DEVICE_ASSIGNMENT
94 static struct kvm_assigned_dev_kernel *kvm_find_assigned_dev(struct list_head *head,
95 						      int assigned_dev_id)
96 {
97 	struct list_head *ptr;
98 	struct kvm_assigned_dev_kernel *match;
99 
100 	list_for_each(ptr, head) {
101 		match = list_entry(ptr, struct kvm_assigned_dev_kernel, list);
102 		if (match->assigned_dev_id == assigned_dev_id)
103 			return match;
104 	}
105 	return NULL;
106 }
107 
108 static int find_index_from_host_irq(struct kvm_assigned_dev_kernel
109 				    *assigned_dev, int irq)
110 {
111 	int i, index;
112 	struct msix_entry *host_msix_entries;
113 
114 	host_msix_entries = assigned_dev->host_msix_entries;
115 
116 	index = -1;
117 	for (i = 0; i < assigned_dev->entries_nr; i++)
118 		if (irq == host_msix_entries[i].vector) {
119 			index = i;
120 			break;
121 		}
122 	if (index < 0) {
123 		printk(KERN_WARNING "Fail to find correlated MSI-X entry!\n");
124 		return 0;
125 	}
126 
127 	return index;
128 }
129 
130 static void kvm_assigned_dev_interrupt_work_handler(struct work_struct *work)
131 {
132 	struct kvm_assigned_dev_kernel *assigned_dev;
133 	struct kvm *kvm;
134 	int i;
135 
136 	assigned_dev = container_of(work, struct kvm_assigned_dev_kernel,
137 				    interrupt_work);
138 	kvm = assigned_dev->kvm;
139 
140 	mutex_lock(&kvm->irq_lock);
141 	spin_lock_irq(&assigned_dev->assigned_dev_lock);
142 	if (assigned_dev->irq_requested_type & KVM_DEV_IRQ_HOST_MSIX) {
143 		struct kvm_guest_msix_entry *guest_entries =
144 			assigned_dev->guest_msix_entries;
145 		for (i = 0; i < assigned_dev->entries_nr; i++) {
146 			if (!(guest_entries[i].flags &
147 					KVM_ASSIGNED_MSIX_PENDING))
148 				continue;
149 			guest_entries[i].flags &= ~KVM_ASSIGNED_MSIX_PENDING;
150 			kvm_set_irq(assigned_dev->kvm,
151 				    assigned_dev->irq_source_id,
152 				    guest_entries[i].vector, 1);
153 		}
154 	} else
155 		kvm_set_irq(assigned_dev->kvm, assigned_dev->irq_source_id,
156 			    assigned_dev->guest_irq, 1);
157 
158 	spin_unlock_irq(&assigned_dev->assigned_dev_lock);
159 	mutex_unlock(&assigned_dev->kvm->irq_lock);
160 }
161 
162 static irqreturn_t kvm_assigned_dev_intr(int irq, void *dev_id)
163 {
164 	unsigned long flags;
165 	struct kvm_assigned_dev_kernel *assigned_dev =
166 		(struct kvm_assigned_dev_kernel *) dev_id;
167 
168 	spin_lock_irqsave(&assigned_dev->assigned_dev_lock, flags);
169 	if (assigned_dev->irq_requested_type & KVM_DEV_IRQ_HOST_MSIX) {
170 		int index = find_index_from_host_irq(assigned_dev, irq);
171 		if (index < 0)
172 			goto out;
173 		assigned_dev->guest_msix_entries[index].flags |=
174 			KVM_ASSIGNED_MSIX_PENDING;
175 	}
176 
177 	schedule_work(&assigned_dev->interrupt_work);
178 
179 	if (assigned_dev->irq_requested_type & KVM_DEV_IRQ_GUEST_INTX) {
180 		disable_irq_nosync(irq);
181 		assigned_dev->host_irq_disabled = true;
182 	}
183 
184 out:
185 	spin_unlock_irqrestore(&assigned_dev->assigned_dev_lock, flags);
186 	return IRQ_HANDLED;
187 }
188 
189 /* Ack the irq line for an assigned device */
190 static void kvm_assigned_dev_ack_irq(struct kvm_irq_ack_notifier *kian)
191 {
192 	struct kvm_assigned_dev_kernel *dev;
193 	unsigned long flags;
194 
195 	if (kian->gsi == -1)
196 		return;
197 
198 	dev = container_of(kian, struct kvm_assigned_dev_kernel,
199 			   ack_notifier);
200 
201 	kvm_set_irq(dev->kvm, dev->irq_source_id, dev->guest_irq, 0);
202 
203 	/* The guest irq may be shared so this ack may be
204 	 * from another device.
205 	 */
206 	spin_lock_irqsave(&dev->assigned_dev_lock, flags);
207 	if (dev->host_irq_disabled) {
208 		enable_irq(dev->host_irq);
209 		dev->host_irq_disabled = false;
210 	}
211 	spin_unlock_irqrestore(&dev->assigned_dev_lock, flags);
212 }
213 
214 static void deassign_guest_irq(struct kvm *kvm,
215 			       struct kvm_assigned_dev_kernel *assigned_dev)
216 {
217 	kvm_unregister_irq_ack_notifier(kvm, &assigned_dev->ack_notifier);
218 	assigned_dev->ack_notifier.gsi = -1;
219 
220 	if (assigned_dev->irq_source_id != -1)
221 		kvm_free_irq_source_id(kvm, assigned_dev->irq_source_id);
222 	assigned_dev->irq_source_id = -1;
223 	assigned_dev->irq_requested_type &= ~(KVM_DEV_IRQ_GUEST_MASK);
224 }
225 
226 /* The function implicit hold kvm->lock mutex due to cancel_work_sync() */
227 static void deassign_host_irq(struct kvm *kvm,
228 			      struct kvm_assigned_dev_kernel *assigned_dev)
229 {
230 	/*
231 	 * In kvm_free_device_irq, cancel_work_sync return true if:
232 	 * 1. work is scheduled, and then cancelled.
233 	 * 2. work callback is executed.
234 	 *
235 	 * The first one ensured that the irq is disabled and no more events
236 	 * would happen. But for the second one, the irq may be enabled (e.g.
237 	 * for MSI). So we disable irq here to prevent further events.
238 	 *
239 	 * Notice this maybe result in nested disable if the interrupt type is
240 	 * INTx, but it's OK for we are going to free it.
241 	 *
242 	 * If this function is a part of VM destroy, please ensure that till
243 	 * now, the kvm state is still legal for probably we also have to wait
244 	 * interrupt_work done.
245 	 */
246 	if (assigned_dev->irq_requested_type & KVM_DEV_IRQ_HOST_MSIX) {
247 		int i;
248 		for (i = 0; i < assigned_dev->entries_nr; i++)
249 			disable_irq_nosync(assigned_dev->
250 					   host_msix_entries[i].vector);
251 
252 		cancel_work_sync(&assigned_dev->interrupt_work);
253 
254 		for (i = 0; i < assigned_dev->entries_nr; i++)
255 			free_irq(assigned_dev->host_msix_entries[i].vector,
256 				 (void *)assigned_dev);
257 
258 		assigned_dev->entries_nr = 0;
259 		kfree(assigned_dev->host_msix_entries);
260 		kfree(assigned_dev->guest_msix_entries);
261 		pci_disable_msix(assigned_dev->dev);
262 	} else {
263 		/* Deal with MSI and INTx */
264 		disable_irq_nosync(assigned_dev->host_irq);
265 		cancel_work_sync(&assigned_dev->interrupt_work);
266 
267 		free_irq(assigned_dev->host_irq, (void *)assigned_dev);
268 
269 		if (assigned_dev->irq_requested_type & KVM_DEV_IRQ_HOST_MSI)
270 			pci_disable_msi(assigned_dev->dev);
271 	}
272 
273 	assigned_dev->irq_requested_type &= ~(KVM_DEV_IRQ_HOST_MASK);
274 }
275 
276 static int kvm_deassign_irq(struct kvm *kvm,
277 			    struct kvm_assigned_dev_kernel *assigned_dev,
278 			    unsigned long irq_requested_type)
279 {
280 	unsigned long guest_irq_type, host_irq_type;
281 
282 	if (!irqchip_in_kernel(kvm))
283 		return -EINVAL;
284 	/* no irq assignment to deassign */
285 	if (!assigned_dev->irq_requested_type)
286 		return -ENXIO;
287 
288 	host_irq_type = irq_requested_type & KVM_DEV_IRQ_HOST_MASK;
289 	guest_irq_type = irq_requested_type & KVM_DEV_IRQ_GUEST_MASK;
290 
291 	if (host_irq_type)
292 		deassign_host_irq(kvm, assigned_dev);
293 	if (guest_irq_type)
294 		deassign_guest_irq(kvm, assigned_dev);
295 
296 	return 0;
297 }
298 
299 static void kvm_free_assigned_irq(struct kvm *kvm,
300 				  struct kvm_assigned_dev_kernel *assigned_dev)
301 {
302 	kvm_deassign_irq(kvm, assigned_dev, assigned_dev->irq_requested_type);
303 }
304 
305 static void kvm_free_assigned_device(struct kvm *kvm,
306 				     struct kvm_assigned_dev_kernel
307 				     *assigned_dev)
308 {
309 	kvm_free_assigned_irq(kvm, assigned_dev);
310 
311 	pci_reset_function(assigned_dev->dev);
312 
313 	pci_release_regions(assigned_dev->dev);
314 	pci_disable_device(assigned_dev->dev);
315 	pci_dev_put(assigned_dev->dev);
316 
317 	list_del(&assigned_dev->list);
318 	kfree(assigned_dev);
319 }
320 
321 void kvm_free_all_assigned_devices(struct kvm *kvm)
322 {
323 	struct list_head *ptr, *ptr2;
324 	struct kvm_assigned_dev_kernel *assigned_dev;
325 
326 	list_for_each_safe(ptr, ptr2, &kvm->arch.assigned_dev_head) {
327 		assigned_dev = list_entry(ptr,
328 					  struct kvm_assigned_dev_kernel,
329 					  list);
330 
331 		kvm_free_assigned_device(kvm, assigned_dev);
332 	}
333 }
334 
335 static int assigned_device_enable_host_intx(struct kvm *kvm,
336 					    struct kvm_assigned_dev_kernel *dev)
337 {
338 	dev->host_irq = dev->dev->irq;
339 	/* Even though this is PCI, we don't want to use shared
340 	 * interrupts. Sharing host devices with guest-assigned devices
341 	 * on the same interrupt line is not a happy situation: there
342 	 * are going to be long delays in accepting, acking, etc.
343 	 */
344 	if (request_irq(dev->host_irq, kvm_assigned_dev_intr,
345 			0, "kvm_assigned_intx_device", (void *)dev))
346 		return -EIO;
347 	return 0;
348 }
349 
350 #ifdef __KVM_HAVE_MSI
351 static int assigned_device_enable_host_msi(struct kvm *kvm,
352 					   struct kvm_assigned_dev_kernel *dev)
353 {
354 	int r;
355 
356 	if (!dev->dev->msi_enabled) {
357 		r = pci_enable_msi(dev->dev);
358 		if (r)
359 			return r;
360 	}
361 
362 	dev->host_irq = dev->dev->irq;
363 	if (request_irq(dev->host_irq, kvm_assigned_dev_intr, 0,
364 			"kvm_assigned_msi_device", (void *)dev)) {
365 		pci_disable_msi(dev->dev);
366 		return -EIO;
367 	}
368 
369 	return 0;
370 }
371 #endif
372 
373 #ifdef __KVM_HAVE_MSIX
374 static int assigned_device_enable_host_msix(struct kvm *kvm,
375 					    struct kvm_assigned_dev_kernel *dev)
376 {
377 	int i, r = -EINVAL;
378 
379 	/* host_msix_entries and guest_msix_entries should have been
380 	 * initialized */
381 	if (dev->entries_nr == 0)
382 		return r;
383 
384 	r = pci_enable_msix(dev->dev, dev->host_msix_entries, dev->entries_nr);
385 	if (r)
386 		return r;
387 
388 	for (i = 0; i < dev->entries_nr; i++) {
389 		r = request_irq(dev->host_msix_entries[i].vector,
390 				kvm_assigned_dev_intr, 0,
391 				"kvm_assigned_msix_device",
392 				(void *)dev);
393 		/* FIXME: free requested_irq's on failure */
394 		if (r)
395 			return r;
396 	}
397 
398 	return 0;
399 }
400 
401 #endif
402 
403 static int assigned_device_enable_guest_intx(struct kvm *kvm,
404 				struct kvm_assigned_dev_kernel *dev,
405 				struct kvm_assigned_irq *irq)
406 {
407 	dev->guest_irq = irq->guest_irq;
408 	dev->ack_notifier.gsi = irq->guest_irq;
409 	return 0;
410 }
411 
412 #ifdef __KVM_HAVE_MSI
413 static int assigned_device_enable_guest_msi(struct kvm *kvm,
414 			struct kvm_assigned_dev_kernel *dev,
415 			struct kvm_assigned_irq *irq)
416 {
417 	dev->guest_irq = irq->guest_irq;
418 	dev->ack_notifier.gsi = -1;
419 	dev->host_irq_disabled = false;
420 	return 0;
421 }
422 #endif
423 #ifdef __KVM_HAVE_MSIX
424 static int assigned_device_enable_guest_msix(struct kvm *kvm,
425 			struct kvm_assigned_dev_kernel *dev,
426 			struct kvm_assigned_irq *irq)
427 {
428 	dev->guest_irq = irq->guest_irq;
429 	dev->ack_notifier.gsi = -1;
430 	dev->host_irq_disabled = false;
431 	return 0;
432 }
433 #endif
434 
435 static int assign_host_irq(struct kvm *kvm,
436 			   struct kvm_assigned_dev_kernel *dev,
437 			   __u32 host_irq_type)
438 {
439 	int r = -EEXIST;
440 
441 	if (dev->irq_requested_type & KVM_DEV_IRQ_HOST_MASK)
442 		return r;
443 
444 	switch (host_irq_type) {
445 	case KVM_DEV_IRQ_HOST_INTX:
446 		r = assigned_device_enable_host_intx(kvm, dev);
447 		break;
448 #ifdef __KVM_HAVE_MSI
449 	case KVM_DEV_IRQ_HOST_MSI:
450 		r = assigned_device_enable_host_msi(kvm, dev);
451 		break;
452 #endif
453 #ifdef __KVM_HAVE_MSIX
454 	case KVM_DEV_IRQ_HOST_MSIX:
455 		r = assigned_device_enable_host_msix(kvm, dev);
456 		break;
457 #endif
458 	default:
459 		r = -EINVAL;
460 	}
461 
462 	if (!r)
463 		dev->irq_requested_type |= host_irq_type;
464 
465 	return r;
466 }
467 
468 static int assign_guest_irq(struct kvm *kvm,
469 			    struct kvm_assigned_dev_kernel *dev,
470 			    struct kvm_assigned_irq *irq,
471 			    unsigned long guest_irq_type)
472 {
473 	int id;
474 	int r = -EEXIST;
475 
476 	if (dev->irq_requested_type & KVM_DEV_IRQ_GUEST_MASK)
477 		return r;
478 
479 	id = kvm_request_irq_source_id(kvm);
480 	if (id < 0)
481 		return id;
482 
483 	dev->irq_source_id = id;
484 
485 	switch (guest_irq_type) {
486 	case KVM_DEV_IRQ_GUEST_INTX:
487 		r = assigned_device_enable_guest_intx(kvm, dev, irq);
488 		break;
489 #ifdef __KVM_HAVE_MSI
490 	case KVM_DEV_IRQ_GUEST_MSI:
491 		r = assigned_device_enable_guest_msi(kvm, dev, irq);
492 		break;
493 #endif
494 #ifdef __KVM_HAVE_MSIX
495 	case KVM_DEV_IRQ_GUEST_MSIX:
496 		r = assigned_device_enable_guest_msix(kvm, dev, irq);
497 		break;
498 #endif
499 	default:
500 		r = -EINVAL;
501 	}
502 
503 	if (!r) {
504 		dev->irq_requested_type |= guest_irq_type;
505 		kvm_register_irq_ack_notifier(kvm, &dev->ack_notifier);
506 	} else
507 		kvm_free_irq_source_id(kvm, dev->irq_source_id);
508 
509 	return r;
510 }
511 
512 /* TODO Deal with KVM_DEV_IRQ_ASSIGNED_MASK_MSIX */
513 static int kvm_vm_ioctl_assign_irq(struct kvm *kvm,
514 				   struct kvm_assigned_irq *assigned_irq)
515 {
516 	int r = -EINVAL;
517 	struct kvm_assigned_dev_kernel *match;
518 	unsigned long host_irq_type, guest_irq_type;
519 
520 	if (!capable(CAP_SYS_RAWIO))
521 		return -EPERM;
522 
523 	if (!irqchip_in_kernel(kvm))
524 		return r;
525 
526 	mutex_lock(&kvm->lock);
527 	r = -ENODEV;
528 	match = kvm_find_assigned_dev(&kvm->arch.assigned_dev_head,
529 				      assigned_irq->assigned_dev_id);
530 	if (!match)
531 		goto out;
532 
533 	host_irq_type = (assigned_irq->flags & KVM_DEV_IRQ_HOST_MASK);
534 	guest_irq_type = (assigned_irq->flags & KVM_DEV_IRQ_GUEST_MASK);
535 
536 	r = -EINVAL;
537 	/* can only assign one type at a time */
538 	if (hweight_long(host_irq_type) > 1)
539 		goto out;
540 	if (hweight_long(guest_irq_type) > 1)
541 		goto out;
542 	if (host_irq_type == 0 && guest_irq_type == 0)
543 		goto out;
544 
545 	r = 0;
546 	if (host_irq_type)
547 		r = assign_host_irq(kvm, match, host_irq_type);
548 	if (r)
549 		goto out;
550 
551 	if (guest_irq_type)
552 		r = assign_guest_irq(kvm, match, assigned_irq, guest_irq_type);
553 out:
554 	mutex_unlock(&kvm->lock);
555 	return r;
556 }
557 
558 static int kvm_vm_ioctl_deassign_dev_irq(struct kvm *kvm,
559 					 struct kvm_assigned_irq
560 					 *assigned_irq)
561 {
562 	int r = -ENODEV;
563 	struct kvm_assigned_dev_kernel *match;
564 
565 	mutex_lock(&kvm->lock);
566 
567 	match = kvm_find_assigned_dev(&kvm->arch.assigned_dev_head,
568 				      assigned_irq->assigned_dev_id);
569 	if (!match)
570 		goto out;
571 
572 	r = kvm_deassign_irq(kvm, match, assigned_irq->flags);
573 out:
574 	mutex_unlock(&kvm->lock);
575 	return r;
576 }
577 
578 static int kvm_vm_ioctl_assign_device(struct kvm *kvm,
579 				      struct kvm_assigned_pci_dev *assigned_dev)
580 {
581 	int r = 0;
582 	struct kvm_assigned_dev_kernel *match;
583 	struct pci_dev *dev;
584 
585 	down_read(&kvm->slots_lock);
586 	mutex_lock(&kvm->lock);
587 
588 	match = kvm_find_assigned_dev(&kvm->arch.assigned_dev_head,
589 				      assigned_dev->assigned_dev_id);
590 	if (match) {
591 		/* device already assigned */
592 		r = -EEXIST;
593 		goto out;
594 	}
595 
596 	match = kzalloc(sizeof(struct kvm_assigned_dev_kernel), GFP_KERNEL);
597 	if (match == NULL) {
598 		printk(KERN_INFO "%s: Couldn't allocate memory\n",
599 		       __func__);
600 		r = -ENOMEM;
601 		goto out;
602 	}
603 	dev = pci_get_bus_and_slot(assigned_dev->busnr,
604 				   assigned_dev->devfn);
605 	if (!dev) {
606 		printk(KERN_INFO "%s: host device not found\n", __func__);
607 		r = -EINVAL;
608 		goto out_free;
609 	}
610 	if (pci_enable_device(dev)) {
611 		printk(KERN_INFO "%s: Could not enable PCI device\n", __func__);
612 		r = -EBUSY;
613 		goto out_put;
614 	}
615 	r = pci_request_regions(dev, "kvm_assigned_device");
616 	if (r) {
617 		printk(KERN_INFO "%s: Could not get access to device regions\n",
618 		       __func__);
619 		goto out_disable;
620 	}
621 
622 	pci_reset_function(dev);
623 
624 	match->assigned_dev_id = assigned_dev->assigned_dev_id;
625 	match->host_busnr = assigned_dev->busnr;
626 	match->host_devfn = assigned_dev->devfn;
627 	match->flags = assigned_dev->flags;
628 	match->dev = dev;
629 	spin_lock_init(&match->assigned_dev_lock);
630 	match->irq_source_id = -1;
631 	match->kvm = kvm;
632 	match->ack_notifier.irq_acked = kvm_assigned_dev_ack_irq;
633 	INIT_WORK(&match->interrupt_work,
634 		  kvm_assigned_dev_interrupt_work_handler);
635 
636 	list_add(&match->list, &kvm->arch.assigned_dev_head);
637 
638 	if (assigned_dev->flags & KVM_DEV_ASSIGN_ENABLE_IOMMU) {
639 		if (!kvm->arch.iommu_domain) {
640 			r = kvm_iommu_map_guest(kvm);
641 			if (r)
642 				goto out_list_del;
643 		}
644 		r = kvm_assign_device(kvm, match);
645 		if (r)
646 			goto out_list_del;
647 	}
648 
649 out:
650 	mutex_unlock(&kvm->lock);
651 	up_read(&kvm->slots_lock);
652 	return r;
653 out_list_del:
654 	list_del(&match->list);
655 	pci_release_regions(dev);
656 out_disable:
657 	pci_disable_device(dev);
658 out_put:
659 	pci_dev_put(dev);
660 out_free:
661 	kfree(match);
662 	mutex_unlock(&kvm->lock);
663 	up_read(&kvm->slots_lock);
664 	return r;
665 }
666 #endif
667 
668 #ifdef KVM_CAP_DEVICE_DEASSIGNMENT
669 static int kvm_vm_ioctl_deassign_device(struct kvm *kvm,
670 		struct kvm_assigned_pci_dev *assigned_dev)
671 {
672 	int r = 0;
673 	struct kvm_assigned_dev_kernel *match;
674 
675 	mutex_lock(&kvm->lock);
676 
677 	match = kvm_find_assigned_dev(&kvm->arch.assigned_dev_head,
678 				      assigned_dev->assigned_dev_id);
679 	if (!match) {
680 		printk(KERN_INFO "%s: device hasn't been assigned before, "
681 		  "so cannot be deassigned\n", __func__);
682 		r = -EINVAL;
683 		goto out;
684 	}
685 
686 	if (match->flags & KVM_DEV_ASSIGN_ENABLE_IOMMU)
687 		kvm_deassign_device(kvm, match);
688 
689 	kvm_free_assigned_device(kvm, match);
690 
691 out:
692 	mutex_unlock(&kvm->lock);
693 	return r;
694 }
695 #endif
696 
697 inline int kvm_is_mmio_pfn(pfn_t pfn)
698 {
699 	if (pfn_valid(pfn)) {
700 		struct page *page = compound_head(pfn_to_page(pfn));
701 		return PageReserved(page);
702 	}
703 
704 	return true;
705 }
706 
707 /*
708  * Switches to specified vcpu, until a matching vcpu_put()
709  */
710 void vcpu_load(struct kvm_vcpu *vcpu)
711 {
712 	int cpu;
713 
714 	mutex_lock(&vcpu->mutex);
715 	cpu = get_cpu();
716 	preempt_notifier_register(&vcpu->preempt_notifier);
717 	kvm_arch_vcpu_load(vcpu, cpu);
718 	put_cpu();
719 }
720 
721 void vcpu_put(struct kvm_vcpu *vcpu)
722 {
723 	preempt_disable();
724 	kvm_arch_vcpu_put(vcpu);
725 	preempt_notifier_unregister(&vcpu->preempt_notifier);
726 	preempt_enable();
727 	mutex_unlock(&vcpu->mutex);
728 }
729 
730 static void ack_flush(void *_completed)
731 {
732 }
733 
734 static bool make_all_cpus_request(struct kvm *kvm, unsigned int req)
735 {
736 	int i, cpu, me;
737 	cpumask_var_t cpus;
738 	bool called = true;
739 	struct kvm_vcpu *vcpu;
740 
741 	zalloc_cpumask_var(&cpus, GFP_ATOMIC);
742 
743 	spin_lock(&kvm->requests_lock);
744 	me = smp_processor_id();
745 	kvm_for_each_vcpu(i, vcpu, kvm) {
746 		if (test_and_set_bit(req, &vcpu->requests))
747 			continue;
748 		cpu = vcpu->cpu;
749 		if (cpus != NULL && cpu != -1 && cpu != me)
750 			cpumask_set_cpu(cpu, cpus);
751 	}
752 	if (unlikely(cpus == NULL))
753 		smp_call_function_many(cpu_online_mask, ack_flush, NULL, 1);
754 	else if (!cpumask_empty(cpus))
755 		smp_call_function_many(cpus, ack_flush, NULL, 1);
756 	else
757 		called = false;
758 	spin_unlock(&kvm->requests_lock);
759 	free_cpumask_var(cpus);
760 	return called;
761 }
762 
763 void kvm_flush_remote_tlbs(struct kvm *kvm)
764 {
765 	if (make_all_cpus_request(kvm, KVM_REQ_TLB_FLUSH))
766 		++kvm->stat.remote_tlb_flush;
767 }
768 
769 void kvm_reload_remote_mmus(struct kvm *kvm)
770 {
771 	make_all_cpus_request(kvm, KVM_REQ_MMU_RELOAD);
772 }
773 
774 int kvm_vcpu_init(struct kvm_vcpu *vcpu, struct kvm *kvm, unsigned id)
775 {
776 	struct page *page;
777 	int r;
778 
779 	mutex_init(&vcpu->mutex);
780 	vcpu->cpu = -1;
781 	vcpu->kvm = kvm;
782 	vcpu->vcpu_id = id;
783 	init_waitqueue_head(&vcpu->wq);
784 
785 	page = alloc_page(GFP_KERNEL | __GFP_ZERO);
786 	if (!page) {
787 		r = -ENOMEM;
788 		goto fail;
789 	}
790 	vcpu->run = page_address(page);
791 
792 	r = kvm_arch_vcpu_init(vcpu);
793 	if (r < 0)
794 		goto fail_free_run;
795 	return 0;
796 
797 fail_free_run:
798 	free_page((unsigned long)vcpu->run);
799 fail:
800 	return r;
801 }
802 EXPORT_SYMBOL_GPL(kvm_vcpu_init);
803 
804 void kvm_vcpu_uninit(struct kvm_vcpu *vcpu)
805 {
806 	kvm_arch_vcpu_uninit(vcpu);
807 	free_page((unsigned long)vcpu->run);
808 }
809 EXPORT_SYMBOL_GPL(kvm_vcpu_uninit);
810 
811 #if defined(CONFIG_MMU_NOTIFIER) && defined(KVM_ARCH_WANT_MMU_NOTIFIER)
812 static inline struct kvm *mmu_notifier_to_kvm(struct mmu_notifier *mn)
813 {
814 	return container_of(mn, struct kvm, mmu_notifier);
815 }
816 
817 static void kvm_mmu_notifier_invalidate_page(struct mmu_notifier *mn,
818 					     struct mm_struct *mm,
819 					     unsigned long address)
820 {
821 	struct kvm *kvm = mmu_notifier_to_kvm(mn);
822 	int need_tlb_flush;
823 
824 	/*
825 	 * When ->invalidate_page runs, the linux pte has been zapped
826 	 * already but the page is still allocated until
827 	 * ->invalidate_page returns. So if we increase the sequence
828 	 * here the kvm page fault will notice if the spte can't be
829 	 * established because the page is going to be freed. If
830 	 * instead the kvm page fault establishes the spte before
831 	 * ->invalidate_page runs, kvm_unmap_hva will release it
832 	 * before returning.
833 	 *
834 	 * The sequence increase only need to be seen at spin_unlock
835 	 * time, and not at spin_lock time.
836 	 *
837 	 * Increasing the sequence after the spin_unlock would be
838 	 * unsafe because the kvm page fault could then establish the
839 	 * pte after kvm_unmap_hva returned, without noticing the page
840 	 * is going to be freed.
841 	 */
842 	spin_lock(&kvm->mmu_lock);
843 	kvm->mmu_notifier_seq++;
844 	need_tlb_flush = kvm_unmap_hva(kvm, address);
845 	spin_unlock(&kvm->mmu_lock);
846 
847 	/* we've to flush the tlb before the pages can be freed */
848 	if (need_tlb_flush)
849 		kvm_flush_remote_tlbs(kvm);
850 
851 }
852 
853 static void kvm_mmu_notifier_change_pte(struct mmu_notifier *mn,
854 					struct mm_struct *mm,
855 					unsigned long address,
856 					pte_t pte)
857 {
858 	struct kvm *kvm = mmu_notifier_to_kvm(mn);
859 
860 	spin_lock(&kvm->mmu_lock);
861 	kvm->mmu_notifier_seq++;
862 	kvm_set_spte_hva(kvm, address, pte);
863 	spin_unlock(&kvm->mmu_lock);
864 }
865 
866 static void kvm_mmu_notifier_invalidate_range_start(struct mmu_notifier *mn,
867 						    struct mm_struct *mm,
868 						    unsigned long start,
869 						    unsigned long end)
870 {
871 	struct kvm *kvm = mmu_notifier_to_kvm(mn);
872 	int need_tlb_flush = 0;
873 
874 	spin_lock(&kvm->mmu_lock);
875 	/*
876 	 * The count increase must become visible at unlock time as no
877 	 * spte can be established without taking the mmu_lock and
878 	 * count is also read inside the mmu_lock critical section.
879 	 */
880 	kvm->mmu_notifier_count++;
881 	for (; start < end; start += PAGE_SIZE)
882 		need_tlb_flush |= kvm_unmap_hva(kvm, start);
883 	spin_unlock(&kvm->mmu_lock);
884 
885 	/* we've to flush the tlb before the pages can be freed */
886 	if (need_tlb_flush)
887 		kvm_flush_remote_tlbs(kvm);
888 }
889 
890 static void kvm_mmu_notifier_invalidate_range_end(struct mmu_notifier *mn,
891 						  struct mm_struct *mm,
892 						  unsigned long start,
893 						  unsigned long end)
894 {
895 	struct kvm *kvm = mmu_notifier_to_kvm(mn);
896 
897 	spin_lock(&kvm->mmu_lock);
898 	/*
899 	 * This sequence increase will notify the kvm page fault that
900 	 * the page that is going to be mapped in the spte could have
901 	 * been freed.
902 	 */
903 	kvm->mmu_notifier_seq++;
904 	/*
905 	 * The above sequence increase must be visible before the
906 	 * below count decrease but both values are read by the kvm
907 	 * page fault under mmu_lock spinlock so we don't need to add
908 	 * a smb_wmb() here in between the two.
909 	 */
910 	kvm->mmu_notifier_count--;
911 	spin_unlock(&kvm->mmu_lock);
912 
913 	BUG_ON(kvm->mmu_notifier_count < 0);
914 }
915 
916 static int kvm_mmu_notifier_clear_flush_young(struct mmu_notifier *mn,
917 					      struct mm_struct *mm,
918 					      unsigned long address)
919 {
920 	struct kvm *kvm = mmu_notifier_to_kvm(mn);
921 	int young;
922 
923 	spin_lock(&kvm->mmu_lock);
924 	young = kvm_age_hva(kvm, address);
925 	spin_unlock(&kvm->mmu_lock);
926 
927 	if (young)
928 		kvm_flush_remote_tlbs(kvm);
929 
930 	return young;
931 }
932 
933 static void kvm_mmu_notifier_release(struct mmu_notifier *mn,
934 				     struct mm_struct *mm)
935 {
936 	struct kvm *kvm = mmu_notifier_to_kvm(mn);
937 	kvm_arch_flush_shadow(kvm);
938 }
939 
940 static const struct mmu_notifier_ops kvm_mmu_notifier_ops = {
941 	.invalidate_page	= kvm_mmu_notifier_invalidate_page,
942 	.invalidate_range_start	= kvm_mmu_notifier_invalidate_range_start,
943 	.invalidate_range_end	= kvm_mmu_notifier_invalidate_range_end,
944 	.clear_flush_young	= kvm_mmu_notifier_clear_flush_young,
945 	.change_pte		= kvm_mmu_notifier_change_pte,
946 	.release		= kvm_mmu_notifier_release,
947 };
948 #endif /* CONFIG_MMU_NOTIFIER && KVM_ARCH_WANT_MMU_NOTIFIER */
949 
950 static struct kvm *kvm_create_vm(void)
951 {
952 	struct kvm *kvm = kvm_arch_create_vm();
953 #ifdef KVM_COALESCED_MMIO_PAGE_OFFSET
954 	struct page *page;
955 #endif
956 
957 	if (IS_ERR(kvm))
958 		goto out;
959 #ifdef CONFIG_HAVE_KVM_IRQCHIP
960 	INIT_LIST_HEAD(&kvm->irq_routing);
961 	INIT_HLIST_HEAD(&kvm->mask_notifier_list);
962 #endif
963 
964 #ifdef KVM_COALESCED_MMIO_PAGE_OFFSET
965 	page = alloc_page(GFP_KERNEL | __GFP_ZERO);
966 	if (!page) {
967 		kfree(kvm);
968 		return ERR_PTR(-ENOMEM);
969 	}
970 	kvm->coalesced_mmio_ring =
971 			(struct kvm_coalesced_mmio_ring *)page_address(page);
972 #endif
973 
974 #if defined(CONFIG_MMU_NOTIFIER) && defined(KVM_ARCH_WANT_MMU_NOTIFIER)
975 	{
976 		int err;
977 		kvm->mmu_notifier.ops = &kvm_mmu_notifier_ops;
978 		err = mmu_notifier_register(&kvm->mmu_notifier, current->mm);
979 		if (err) {
980 #ifdef KVM_COALESCED_MMIO_PAGE_OFFSET
981 			put_page(page);
982 #endif
983 			kfree(kvm);
984 			return ERR_PTR(err);
985 		}
986 	}
987 #endif
988 
989 	kvm->mm = current->mm;
990 	atomic_inc(&kvm->mm->mm_count);
991 	spin_lock_init(&kvm->mmu_lock);
992 	spin_lock_init(&kvm->requests_lock);
993 	kvm_io_bus_init(&kvm->pio_bus);
994 	kvm_eventfd_init(kvm);
995 	mutex_init(&kvm->lock);
996 	mutex_init(&kvm->irq_lock);
997 	kvm_io_bus_init(&kvm->mmio_bus);
998 	init_rwsem(&kvm->slots_lock);
999 	atomic_set(&kvm->users_count, 1);
1000 	spin_lock(&kvm_lock);
1001 	list_add(&kvm->vm_list, &vm_list);
1002 	spin_unlock(&kvm_lock);
1003 #ifdef KVM_COALESCED_MMIO_PAGE_OFFSET
1004 	kvm_coalesced_mmio_init(kvm);
1005 #endif
1006 out:
1007 	return kvm;
1008 }
1009 
1010 /*
1011  * Free any memory in @free but not in @dont.
1012  */
1013 static void kvm_free_physmem_slot(struct kvm_memory_slot *free,
1014 				  struct kvm_memory_slot *dont)
1015 {
1016 	int i;
1017 
1018 	if (!dont || free->rmap != dont->rmap)
1019 		vfree(free->rmap);
1020 
1021 	if (!dont || free->dirty_bitmap != dont->dirty_bitmap)
1022 		vfree(free->dirty_bitmap);
1023 
1024 
1025 	for (i = 0; i < KVM_NR_PAGE_SIZES - 1; ++i) {
1026 		if (!dont || free->lpage_info[i] != dont->lpage_info[i]) {
1027 			vfree(free->lpage_info[i]);
1028 			free->lpage_info[i] = NULL;
1029 		}
1030 	}
1031 
1032 	free->npages = 0;
1033 	free->dirty_bitmap = NULL;
1034 	free->rmap = NULL;
1035 }
1036 
1037 void kvm_free_physmem(struct kvm *kvm)
1038 {
1039 	int i;
1040 
1041 	for (i = 0; i < kvm->nmemslots; ++i)
1042 		kvm_free_physmem_slot(&kvm->memslots[i], NULL);
1043 }
1044 
1045 static void kvm_destroy_vm(struct kvm *kvm)
1046 {
1047 	struct mm_struct *mm = kvm->mm;
1048 
1049 	kvm_arch_sync_events(kvm);
1050 	spin_lock(&kvm_lock);
1051 	list_del(&kvm->vm_list);
1052 	spin_unlock(&kvm_lock);
1053 	kvm_free_irq_routing(kvm);
1054 	kvm_io_bus_destroy(&kvm->pio_bus);
1055 	kvm_io_bus_destroy(&kvm->mmio_bus);
1056 #ifdef KVM_COALESCED_MMIO_PAGE_OFFSET
1057 	if (kvm->coalesced_mmio_ring != NULL)
1058 		free_page((unsigned long)kvm->coalesced_mmio_ring);
1059 #endif
1060 #if defined(CONFIG_MMU_NOTIFIER) && defined(KVM_ARCH_WANT_MMU_NOTIFIER)
1061 	mmu_notifier_unregister(&kvm->mmu_notifier, kvm->mm);
1062 #else
1063 	kvm_arch_flush_shadow(kvm);
1064 #endif
1065 	kvm_arch_destroy_vm(kvm);
1066 	mmdrop(mm);
1067 }
1068 
1069 void kvm_get_kvm(struct kvm *kvm)
1070 {
1071 	atomic_inc(&kvm->users_count);
1072 }
1073 EXPORT_SYMBOL_GPL(kvm_get_kvm);
1074 
1075 void kvm_put_kvm(struct kvm *kvm)
1076 {
1077 	if (atomic_dec_and_test(&kvm->users_count))
1078 		kvm_destroy_vm(kvm);
1079 }
1080 EXPORT_SYMBOL_GPL(kvm_put_kvm);
1081 
1082 
1083 static int kvm_vm_release(struct inode *inode, struct file *filp)
1084 {
1085 	struct kvm *kvm = filp->private_data;
1086 
1087 	kvm_irqfd_release(kvm);
1088 
1089 	kvm_put_kvm(kvm);
1090 	return 0;
1091 }
1092 
1093 /*
1094  * Allocate some memory and give it an address in the guest physical address
1095  * space.
1096  *
1097  * Discontiguous memory is allowed, mostly for framebuffers.
1098  *
1099  * Must be called holding mmap_sem for write.
1100  */
1101 int __kvm_set_memory_region(struct kvm *kvm,
1102 			    struct kvm_userspace_memory_region *mem,
1103 			    int user_alloc)
1104 {
1105 	int r;
1106 	gfn_t base_gfn;
1107 	unsigned long npages;
1108 	unsigned long i;
1109 	struct kvm_memory_slot *memslot;
1110 	struct kvm_memory_slot old, new;
1111 
1112 	r = -EINVAL;
1113 	/* General sanity checks */
1114 	if (mem->memory_size & (PAGE_SIZE - 1))
1115 		goto out;
1116 	if (mem->guest_phys_addr & (PAGE_SIZE - 1))
1117 		goto out;
1118 	if (user_alloc && (mem->userspace_addr & (PAGE_SIZE - 1)))
1119 		goto out;
1120 	if (mem->slot >= KVM_MEMORY_SLOTS + KVM_PRIVATE_MEM_SLOTS)
1121 		goto out;
1122 	if (mem->guest_phys_addr + mem->memory_size < mem->guest_phys_addr)
1123 		goto out;
1124 
1125 	memslot = &kvm->memslots[mem->slot];
1126 	base_gfn = mem->guest_phys_addr >> PAGE_SHIFT;
1127 	npages = mem->memory_size >> PAGE_SHIFT;
1128 
1129 	if (!npages)
1130 		mem->flags &= ~KVM_MEM_LOG_DIRTY_PAGES;
1131 
1132 	new = old = *memslot;
1133 
1134 	new.base_gfn = base_gfn;
1135 	new.npages = npages;
1136 	new.flags = mem->flags;
1137 
1138 	/* Disallow changing a memory slot's size. */
1139 	r = -EINVAL;
1140 	if (npages && old.npages && npages != old.npages)
1141 		goto out_free;
1142 
1143 	/* Check for overlaps */
1144 	r = -EEXIST;
1145 	for (i = 0; i < KVM_MEMORY_SLOTS; ++i) {
1146 		struct kvm_memory_slot *s = &kvm->memslots[i];
1147 
1148 		if (s == memslot || !s->npages)
1149 			continue;
1150 		if (!((base_gfn + npages <= s->base_gfn) ||
1151 		      (base_gfn >= s->base_gfn + s->npages)))
1152 			goto out_free;
1153 	}
1154 
1155 	/* Free page dirty bitmap if unneeded */
1156 	if (!(new.flags & KVM_MEM_LOG_DIRTY_PAGES))
1157 		new.dirty_bitmap = NULL;
1158 
1159 	r = -ENOMEM;
1160 
1161 	/* Allocate if a slot is being created */
1162 #ifndef CONFIG_S390
1163 	if (npages && !new.rmap) {
1164 		new.rmap = vmalloc(npages * sizeof(struct page *));
1165 
1166 		if (!new.rmap)
1167 			goto out_free;
1168 
1169 		memset(new.rmap, 0, npages * sizeof(*new.rmap));
1170 
1171 		new.user_alloc = user_alloc;
1172 		/*
1173 		 * hva_to_rmmap() serialzies with the mmu_lock and to be
1174 		 * safe it has to ignore memslots with !user_alloc &&
1175 		 * !userspace_addr.
1176 		 */
1177 		if (user_alloc)
1178 			new.userspace_addr = mem->userspace_addr;
1179 		else
1180 			new.userspace_addr = 0;
1181 	}
1182 	if (!npages)
1183 		goto skip_lpage;
1184 
1185 	for (i = 0; i < KVM_NR_PAGE_SIZES - 1; ++i) {
1186 		unsigned long ugfn;
1187 		unsigned long j;
1188 		int lpages;
1189 		int level = i + 2;
1190 
1191 		/* Avoid unused variable warning if no large pages */
1192 		(void)level;
1193 
1194 		if (new.lpage_info[i])
1195 			continue;
1196 
1197 		lpages = 1 + (base_gfn + npages - 1) /
1198 			     KVM_PAGES_PER_HPAGE(level);
1199 		lpages -= base_gfn / KVM_PAGES_PER_HPAGE(level);
1200 
1201 		new.lpage_info[i] = vmalloc(lpages * sizeof(*new.lpage_info[i]));
1202 
1203 		if (!new.lpage_info[i])
1204 			goto out_free;
1205 
1206 		memset(new.lpage_info[i], 0,
1207 		       lpages * sizeof(*new.lpage_info[i]));
1208 
1209 		if (base_gfn % KVM_PAGES_PER_HPAGE(level))
1210 			new.lpage_info[i][0].write_count = 1;
1211 		if ((base_gfn+npages) % KVM_PAGES_PER_HPAGE(level))
1212 			new.lpage_info[i][lpages - 1].write_count = 1;
1213 		ugfn = new.userspace_addr >> PAGE_SHIFT;
1214 		/*
1215 		 * If the gfn and userspace address are not aligned wrt each
1216 		 * other, or if explicitly asked to, disable large page
1217 		 * support for this slot
1218 		 */
1219 		if ((base_gfn ^ ugfn) & (KVM_PAGES_PER_HPAGE(level) - 1) ||
1220 		    !largepages_enabled)
1221 			for (j = 0; j < lpages; ++j)
1222 				new.lpage_info[i][j].write_count = 1;
1223 	}
1224 
1225 skip_lpage:
1226 
1227 	/* Allocate page dirty bitmap if needed */
1228 	if ((new.flags & KVM_MEM_LOG_DIRTY_PAGES) && !new.dirty_bitmap) {
1229 		unsigned dirty_bytes = ALIGN(npages, BITS_PER_LONG) / 8;
1230 
1231 		new.dirty_bitmap = vmalloc(dirty_bytes);
1232 		if (!new.dirty_bitmap)
1233 			goto out_free;
1234 		memset(new.dirty_bitmap, 0, dirty_bytes);
1235 		if (old.npages)
1236 			kvm_arch_flush_shadow(kvm);
1237 	}
1238 #else  /* not defined CONFIG_S390 */
1239 	new.user_alloc = user_alloc;
1240 	if (user_alloc)
1241 		new.userspace_addr = mem->userspace_addr;
1242 #endif /* not defined CONFIG_S390 */
1243 
1244 	if (!npages)
1245 		kvm_arch_flush_shadow(kvm);
1246 
1247 	spin_lock(&kvm->mmu_lock);
1248 	if (mem->slot >= kvm->nmemslots)
1249 		kvm->nmemslots = mem->slot + 1;
1250 
1251 	*memslot = new;
1252 	spin_unlock(&kvm->mmu_lock);
1253 
1254 	r = kvm_arch_set_memory_region(kvm, mem, old, user_alloc);
1255 	if (r) {
1256 		spin_lock(&kvm->mmu_lock);
1257 		*memslot = old;
1258 		spin_unlock(&kvm->mmu_lock);
1259 		goto out_free;
1260 	}
1261 
1262 	kvm_free_physmem_slot(&old, npages ? &new : NULL);
1263 	/* Slot deletion case: we have to update the current slot */
1264 	spin_lock(&kvm->mmu_lock);
1265 	if (!npages)
1266 		*memslot = old;
1267 	spin_unlock(&kvm->mmu_lock);
1268 #ifdef CONFIG_DMAR
1269 	/* map the pages in iommu page table */
1270 	r = kvm_iommu_map_pages(kvm, base_gfn, npages);
1271 	if (r)
1272 		goto out;
1273 #endif
1274 	return 0;
1275 
1276 out_free:
1277 	kvm_free_physmem_slot(&new, &old);
1278 out:
1279 	return r;
1280 
1281 }
1282 EXPORT_SYMBOL_GPL(__kvm_set_memory_region);
1283 
1284 int kvm_set_memory_region(struct kvm *kvm,
1285 			  struct kvm_userspace_memory_region *mem,
1286 			  int user_alloc)
1287 {
1288 	int r;
1289 
1290 	down_write(&kvm->slots_lock);
1291 	r = __kvm_set_memory_region(kvm, mem, user_alloc);
1292 	up_write(&kvm->slots_lock);
1293 	return r;
1294 }
1295 EXPORT_SYMBOL_GPL(kvm_set_memory_region);
1296 
1297 int kvm_vm_ioctl_set_memory_region(struct kvm *kvm,
1298 				   struct
1299 				   kvm_userspace_memory_region *mem,
1300 				   int user_alloc)
1301 {
1302 	if (mem->slot >= KVM_MEMORY_SLOTS)
1303 		return -EINVAL;
1304 	return kvm_set_memory_region(kvm, mem, user_alloc);
1305 }
1306 
1307 int kvm_get_dirty_log(struct kvm *kvm,
1308 			struct kvm_dirty_log *log, int *is_dirty)
1309 {
1310 	struct kvm_memory_slot *memslot;
1311 	int r, i;
1312 	int n;
1313 	unsigned long any = 0;
1314 
1315 	r = -EINVAL;
1316 	if (log->slot >= KVM_MEMORY_SLOTS)
1317 		goto out;
1318 
1319 	memslot = &kvm->memslots[log->slot];
1320 	r = -ENOENT;
1321 	if (!memslot->dirty_bitmap)
1322 		goto out;
1323 
1324 	n = ALIGN(memslot->npages, BITS_PER_LONG) / 8;
1325 
1326 	for (i = 0; !any && i < n/sizeof(long); ++i)
1327 		any = memslot->dirty_bitmap[i];
1328 
1329 	r = -EFAULT;
1330 	if (copy_to_user(log->dirty_bitmap, memslot->dirty_bitmap, n))
1331 		goto out;
1332 
1333 	if (any)
1334 		*is_dirty = 1;
1335 
1336 	r = 0;
1337 out:
1338 	return r;
1339 }
1340 
1341 void kvm_disable_largepages(void)
1342 {
1343 	largepages_enabled = false;
1344 }
1345 EXPORT_SYMBOL_GPL(kvm_disable_largepages);
1346 
1347 int is_error_page(struct page *page)
1348 {
1349 	return page == bad_page;
1350 }
1351 EXPORT_SYMBOL_GPL(is_error_page);
1352 
1353 int is_error_pfn(pfn_t pfn)
1354 {
1355 	return pfn == bad_pfn;
1356 }
1357 EXPORT_SYMBOL_GPL(is_error_pfn);
1358 
1359 static inline unsigned long bad_hva(void)
1360 {
1361 	return PAGE_OFFSET;
1362 }
1363 
1364 int kvm_is_error_hva(unsigned long addr)
1365 {
1366 	return addr == bad_hva();
1367 }
1368 EXPORT_SYMBOL_GPL(kvm_is_error_hva);
1369 
1370 struct kvm_memory_slot *gfn_to_memslot_unaliased(struct kvm *kvm, gfn_t gfn)
1371 {
1372 	int i;
1373 
1374 	for (i = 0; i < kvm->nmemslots; ++i) {
1375 		struct kvm_memory_slot *memslot = &kvm->memslots[i];
1376 
1377 		if (gfn >= memslot->base_gfn
1378 		    && gfn < memslot->base_gfn + memslot->npages)
1379 			return memslot;
1380 	}
1381 	return NULL;
1382 }
1383 EXPORT_SYMBOL_GPL(gfn_to_memslot_unaliased);
1384 
1385 struct kvm_memory_slot *gfn_to_memslot(struct kvm *kvm, gfn_t gfn)
1386 {
1387 	gfn = unalias_gfn(kvm, gfn);
1388 	return gfn_to_memslot_unaliased(kvm, gfn);
1389 }
1390 
1391 int kvm_is_visible_gfn(struct kvm *kvm, gfn_t gfn)
1392 {
1393 	int i;
1394 
1395 	gfn = unalias_gfn(kvm, gfn);
1396 	for (i = 0; i < KVM_MEMORY_SLOTS; ++i) {
1397 		struct kvm_memory_slot *memslot = &kvm->memslots[i];
1398 
1399 		if (gfn >= memslot->base_gfn
1400 		    && gfn < memslot->base_gfn + memslot->npages)
1401 			return 1;
1402 	}
1403 	return 0;
1404 }
1405 EXPORT_SYMBOL_GPL(kvm_is_visible_gfn);
1406 
1407 unsigned long gfn_to_hva(struct kvm *kvm, gfn_t gfn)
1408 {
1409 	struct kvm_memory_slot *slot;
1410 
1411 	gfn = unalias_gfn(kvm, gfn);
1412 	slot = gfn_to_memslot_unaliased(kvm, gfn);
1413 	if (!slot)
1414 		return bad_hva();
1415 	return (slot->userspace_addr + (gfn - slot->base_gfn) * PAGE_SIZE);
1416 }
1417 EXPORT_SYMBOL_GPL(gfn_to_hva);
1418 
1419 pfn_t gfn_to_pfn(struct kvm *kvm, gfn_t gfn)
1420 {
1421 	struct page *page[1];
1422 	unsigned long addr;
1423 	int npages;
1424 	pfn_t pfn;
1425 
1426 	might_sleep();
1427 
1428 	addr = gfn_to_hva(kvm, gfn);
1429 	if (kvm_is_error_hva(addr)) {
1430 		get_page(bad_page);
1431 		return page_to_pfn(bad_page);
1432 	}
1433 
1434 	npages = get_user_pages_fast(addr, 1, 1, page);
1435 
1436 	if (unlikely(npages != 1)) {
1437 		struct vm_area_struct *vma;
1438 
1439 		down_read(&current->mm->mmap_sem);
1440 		vma = find_vma(current->mm, addr);
1441 
1442 		if (vma == NULL || addr < vma->vm_start ||
1443 		    !(vma->vm_flags & VM_PFNMAP)) {
1444 			up_read(&current->mm->mmap_sem);
1445 			get_page(bad_page);
1446 			return page_to_pfn(bad_page);
1447 		}
1448 
1449 		pfn = ((addr - vma->vm_start) >> PAGE_SHIFT) + vma->vm_pgoff;
1450 		up_read(&current->mm->mmap_sem);
1451 		BUG_ON(!kvm_is_mmio_pfn(pfn));
1452 	} else
1453 		pfn = page_to_pfn(page[0]);
1454 
1455 	return pfn;
1456 }
1457 
1458 EXPORT_SYMBOL_GPL(gfn_to_pfn);
1459 
1460 struct page *gfn_to_page(struct kvm *kvm, gfn_t gfn)
1461 {
1462 	pfn_t pfn;
1463 
1464 	pfn = gfn_to_pfn(kvm, gfn);
1465 	if (!kvm_is_mmio_pfn(pfn))
1466 		return pfn_to_page(pfn);
1467 
1468 	WARN_ON(kvm_is_mmio_pfn(pfn));
1469 
1470 	get_page(bad_page);
1471 	return bad_page;
1472 }
1473 
1474 EXPORT_SYMBOL_GPL(gfn_to_page);
1475 
1476 void kvm_release_page_clean(struct page *page)
1477 {
1478 	kvm_release_pfn_clean(page_to_pfn(page));
1479 }
1480 EXPORT_SYMBOL_GPL(kvm_release_page_clean);
1481 
1482 void kvm_release_pfn_clean(pfn_t pfn)
1483 {
1484 	if (!kvm_is_mmio_pfn(pfn))
1485 		put_page(pfn_to_page(pfn));
1486 }
1487 EXPORT_SYMBOL_GPL(kvm_release_pfn_clean);
1488 
1489 void kvm_release_page_dirty(struct page *page)
1490 {
1491 	kvm_release_pfn_dirty(page_to_pfn(page));
1492 }
1493 EXPORT_SYMBOL_GPL(kvm_release_page_dirty);
1494 
1495 void kvm_release_pfn_dirty(pfn_t pfn)
1496 {
1497 	kvm_set_pfn_dirty(pfn);
1498 	kvm_release_pfn_clean(pfn);
1499 }
1500 EXPORT_SYMBOL_GPL(kvm_release_pfn_dirty);
1501 
1502 void kvm_set_page_dirty(struct page *page)
1503 {
1504 	kvm_set_pfn_dirty(page_to_pfn(page));
1505 }
1506 EXPORT_SYMBOL_GPL(kvm_set_page_dirty);
1507 
1508 void kvm_set_pfn_dirty(pfn_t pfn)
1509 {
1510 	if (!kvm_is_mmio_pfn(pfn)) {
1511 		struct page *page = pfn_to_page(pfn);
1512 		if (!PageReserved(page))
1513 			SetPageDirty(page);
1514 	}
1515 }
1516 EXPORT_SYMBOL_GPL(kvm_set_pfn_dirty);
1517 
1518 void kvm_set_pfn_accessed(pfn_t pfn)
1519 {
1520 	if (!kvm_is_mmio_pfn(pfn))
1521 		mark_page_accessed(pfn_to_page(pfn));
1522 }
1523 EXPORT_SYMBOL_GPL(kvm_set_pfn_accessed);
1524 
1525 void kvm_get_pfn(pfn_t pfn)
1526 {
1527 	if (!kvm_is_mmio_pfn(pfn))
1528 		get_page(pfn_to_page(pfn));
1529 }
1530 EXPORT_SYMBOL_GPL(kvm_get_pfn);
1531 
1532 static int next_segment(unsigned long len, int offset)
1533 {
1534 	if (len > PAGE_SIZE - offset)
1535 		return PAGE_SIZE - offset;
1536 	else
1537 		return len;
1538 }
1539 
1540 int kvm_read_guest_page(struct kvm *kvm, gfn_t gfn, void *data, int offset,
1541 			int len)
1542 {
1543 	int r;
1544 	unsigned long addr;
1545 
1546 	addr = gfn_to_hva(kvm, gfn);
1547 	if (kvm_is_error_hva(addr))
1548 		return -EFAULT;
1549 	r = copy_from_user(data, (void __user *)addr + offset, len);
1550 	if (r)
1551 		return -EFAULT;
1552 	return 0;
1553 }
1554 EXPORT_SYMBOL_GPL(kvm_read_guest_page);
1555 
1556 int kvm_read_guest(struct kvm *kvm, gpa_t gpa, void *data, unsigned long len)
1557 {
1558 	gfn_t gfn = gpa >> PAGE_SHIFT;
1559 	int seg;
1560 	int offset = offset_in_page(gpa);
1561 	int ret;
1562 
1563 	while ((seg = next_segment(len, offset)) != 0) {
1564 		ret = kvm_read_guest_page(kvm, gfn, data, offset, seg);
1565 		if (ret < 0)
1566 			return ret;
1567 		offset = 0;
1568 		len -= seg;
1569 		data += seg;
1570 		++gfn;
1571 	}
1572 	return 0;
1573 }
1574 EXPORT_SYMBOL_GPL(kvm_read_guest);
1575 
1576 int kvm_read_guest_atomic(struct kvm *kvm, gpa_t gpa, void *data,
1577 			  unsigned long len)
1578 {
1579 	int r;
1580 	unsigned long addr;
1581 	gfn_t gfn = gpa >> PAGE_SHIFT;
1582 	int offset = offset_in_page(gpa);
1583 
1584 	addr = gfn_to_hva(kvm, gfn);
1585 	if (kvm_is_error_hva(addr))
1586 		return -EFAULT;
1587 	pagefault_disable();
1588 	r = __copy_from_user_inatomic(data, (void __user *)addr + offset, len);
1589 	pagefault_enable();
1590 	if (r)
1591 		return -EFAULT;
1592 	return 0;
1593 }
1594 EXPORT_SYMBOL(kvm_read_guest_atomic);
1595 
1596 int kvm_write_guest_page(struct kvm *kvm, gfn_t gfn, const void *data,
1597 			 int offset, int len)
1598 {
1599 	int r;
1600 	unsigned long addr;
1601 
1602 	addr = gfn_to_hva(kvm, gfn);
1603 	if (kvm_is_error_hva(addr))
1604 		return -EFAULT;
1605 	r = copy_to_user((void __user *)addr + offset, data, len);
1606 	if (r)
1607 		return -EFAULT;
1608 	mark_page_dirty(kvm, gfn);
1609 	return 0;
1610 }
1611 EXPORT_SYMBOL_GPL(kvm_write_guest_page);
1612 
1613 int kvm_write_guest(struct kvm *kvm, gpa_t gpa, const void *data,
1614 		    unsigned long len)
1615 {
1616 	gfn_t gfn = gpa >> PAGE_SHIFT;
1617 	int seg;
1618 	int offset = offset_in_page(gpa);
1619 	int ret;
1620 
1621 	while ((seg = next_segment(len, offset)) != 0) {
1622 		ret = kvm_write_guest_page(kvm, gfn, data, offset, seg);
1623 		if (ret < 0)
1624 			return ret;
1625 		offset = 0;
1626 		len -= seg;
1627 		data += seg;
1628 		++gfn;
1629 	}
1630 	return 0;
1631 }
1632 
1633 int kvm_clear_guest_page(struct kvm *kvm, gfn_t gfn, int offset, int len)
1634 {
1635 	return kvm_write_guest_page(kvm, gfn, empty_zero_page, offset, len);
1636 }
1637 EXPORT_SYMBOL_GPL(kvm_clear_guest_page);
1638 
1639 int kvm_clear_guest(struct kvm *kvm, gpa_t gpa, unsigned long len)
1640 {
1641 	gfn_t gfn = gpa >> PAGE_SHIFT;
1642 	int seg;
1643 	int offset = offset_in_page(gpa);
1644 	int ret;
1645 
1646         while ((seg = next_segment(len, offset)) != 0) {
1647 		ret = kvm_clear_guest_page(kvm, gfn, offset, seg);
1648 		if (ret < 0)
1649 			return ret;
1650 		offset = 0;
1651 		len -= seg;
1652 		++gfn;
1653 	}
1654 	return 0;
1655 }
1656 EXPORT_SYMBOL_GPL(kvm_clear_guest);
1657 
1658 void mark_page_dirty(struct kvm *kvm, gfn_t gfn)
1659 {
1660 	struct kvm_memory_slot *memslot;
1661 
1662 	gfn = unalias_gfn(kvm, gfn);
1663 	memslot = gfn_to_memslot_unaliased(kvm, gfn);
1664 	if (memslot && memslot->dirty_bitmap) {
1665 		unsigned long rel_gfn = gfn - memslot->base_gfn;
1666 
1667 		/* avoid RMW */
1668 		if (!test_bit(rel_gfn, memslot->dirty_bitmap))
1669 			set_bit(rel_gfn, memslot->dirty_bitmap);
1670 	}
1671 }
1672 
1673 /*
1674  * The vCPU has executed a HLT instruction with in-kernel mode enabled.
1675  */
1676 void kvm_vcpu_block(struct kvm_vcpu *vcpu)
1677 {
1678 	DEFINE_WAIT(wait);
1679 
1680 	for (;;) {
1681 		prepare_to_wait(&vcpu->wq, &wait, TASK_INTERRUPTIBLE);
1682 
1683 		if (kvm_arch_vcpu_runnable(vcpu)) {
1684 			set_bit(KVM_REQ_UNHALT, &vcpu->requests);
1685 			break;
1686 		}
1687 		if (kvm_cpu_has_pending_timer(vcpu))
1688 			break;
1689 		if (signal_pending(current))
1690 			break;
1691 
1692 		vcpu_put(vcpu);
1693 		schedule();
1694 		vcpu_load(vcpu);
1695 	}
1696 
1697 	finish_wait(&vcpu->wq, &wait);
1698 }
1699 
1700 void kvm_resched(struct kvm_vcpu *vcpu)
1701 {
1702 	if (!need_resched())
1703 		return;
1704 	cond_resched();
1705 }
1706 EXPORT_SYMBOL_GPL(kvm_resched);
1707 
1708 static int kvm_vcpu_fault(struct vm_area_struct *vma, struct vm_fault *vmf)
1709 {
1710 	struct kvm_vcpu *vcpu = vma->vm_file->private_data;
1711 	struct page *page;
1712 
1713 	if (vmf->pgoff == 0)
1714 		page = virt_to_page(vcpu->run);
1715 #ifdef CONFIG_X86
1716 	else if (vmf->pgoff == KVM_PIO_PAGE_OFFSET)
1717 		page = virt_to_page(vcpu->arch.pio_data);
1718 #endif
1719 #ifdef KVM_COALESCED_MMIO_PAGE_OFFSET
1720 	else if (vmf->pgoff == KVM_COALESCED_MMIO_PAGE_OFFSET)
1721 		page = virt_to_page(vcpu->kvm->coalesced_mmio_ring);
1722 #endif
1723 	else
1724 		return VM_FAULT_SIGBUS;
1725 	get_page(page);
1726 	vmf->page = page;
1727 	return 0;
1728 }
1729 
1730 static const struct vm_operations_struct kvm_vcpu_vm_ops = {
1731 	.fault = kvm_vcpu_fault,
1732 };
1733 
1734 static int kvm_vcpu_mmap(struct file *file, struct vm_area_struct *vma)
1735 {
1736 	vma->vm_ops = &kvm_vcpu_vm_ops;
1737 	return 0;
1738 }
1739 
1740 static int kvm_vcpu_release(struct inode *inode, struct file *filp)
1741 {
1742 	struct kvm_vcpu *vcpu = filp->private_data;
1743 
1744 	kvm_put_kvm(vcpu->kvm);
1745 	return 0;
1746 }
1747 
1748 static struct file_operations kvm_vcpu_fops = {
1749 	.release        = kvm_vcpu_release,
1750 	.unlocked_ioctl = kvm_vcpu_ioctl,
1751 	.compat_ioctl   = kvm_vcpu_ioctl,
1752 	.mmap           = kvm_vcpu_mmap,
1753 };
1754 
1755 /*
1756  * Allocates an inode for the vcpu.
1757  */
1758 static int create_vcpu_fd(struct kvm_vcpu *vcpu)
1759 {
1760 	return anon_inode_getfd("kvm-vcpu", &kvm_vcpu_fops, vcpu, 0);
1761 }
1762 
1763 /*
1764  * Creates some virtual cpus.  Good luck creating more than one.
1765  */
1766 static int kvm_vm_ioctl_create_vcpu(struct kvm *kvm, u32 id)
1767 {
1768 	int r;
1769 	struct kvm_vcpu *vcpu, *v;
1770 
1771 	vcpu = kvm_arch_vcpu_create(kvm, id);
1772 	if (IS_ERR(vcpu))
1773 		return PTR_ERR(vcpu);
1774 
1775 	preempt_notifier_init(&vcpu->preempt_notifier, &kvm_preempt_ops);
1776 
1777 	r = kvm_arch_vcpu_setup(vcpu);
1778 	if (r)
1779 		return r;
1780 
1781 	mutex_lock(&kvm->lock);
1782 	if (atomic_read(&kvm->online_vcpus) == KVM_MAX_VCPUS) {
1783 		r = -EINVAL;
1784 		goto vcpu_destroy;
1785 	}
1786 
1787 	kvm_for_each_vcpu(r, v, kvm)
1788 		if (v->vcpu_id == id) {
1789 			r = -EEXIST;
1790 			goto vcpu_destroy;
1791 		}
1792 
1793 	BUG_ON(kvm->vcpus[atomic_read(&kvm->online_vcpus)]);
1794 
1795 	/* Now it's all set up, let userspace reach it */
1796 	kvm_get_kvm(kvm);
1797 	r = create_vcpu_fd(vcpu);
1798 	if (r < 0) {
1799 		kvm_put_kvm(kvm);
1800 		goto vcpu_destroy;
1801 	}
1802 
1803 	kvm->vcpus[atomic_read(&kvm->online_vcpus)] = vcpu;
1804 	smp_wmb();
1805 	atomic_inc(&kvm->online_vcpus);
1806 
1807 #ifdef CONFIG_KVM_APIC_ARCHITECTURE
1808 	if (kvm->bsp_vcpu_id == id)
1809 		kvm->bsp_vcpu = vcpu;
1810 #endif
1811 	mutex_unlock(&kvm->lock);
1812 	return r;
1813 
1814 vcpu_destroy:
1815 	mutex_unlock(&kvm->lock);
1816 	kvm_arch_vcpu_destroy(vcpu);
1817 	return r;
1818 }
1819 
1820 static int kvm_vcpu_ioctl_set_sigmask(struct kvm_vcpu *vcpu, sigset_t *sigset)
1821 {
1822 	if (sigset) {
1823 		sigdelsetmask(sigset, sigmask(SIGKILL)|sigmask(SIGSTOP));
1824 		vcpu->sigset_active = 1;
1825 		vcpu->sigset = *sigset;
1826 	} else
1827 		vcpu->sigset_active = 0;
1828 	return 0;
1829 }
1830 
1831 #ifdef __KVM_HAVE_MSIX
1832 static int kvm_vm_ioctl_set_msix_nr(struct kvm *kvm,
1833 				    struct kvm_assigned_msix_nr *entry_nr)
1834 {
1835 	int r = 0;
1836 	struct kvm_assigned_dev_kernel *adev;
1837 
1838 	mutex_lock(&kvm->lock);
1839 
1840 	adev = kvm_find_assigned_dev(&kvm->arch.assigned_dev_head,
1841 				      entry_nr->assigned_dev_id);
1842 	if (!adev) {
1843 		r = -EINVAL;
1844 		goto msix_nr_out;
1845 	}
1846 
1847 	if (adev->entries_nr == 0) {
1848 		adev->entries_nr = entry_nr->entry_nr;
1849 		if (adev->entries_nr == 0 ||
1850 		    adev->entries_nr >= KVM_MAX_MSIX_PER_DEV) {
1851 			r = -EINVAL;
1852 			goto msix_nr_out;
1853 		}
1854 
1855 		adev->host_msix_entries = kzalloc(sizeof(struct msix_entry) *
1856 						entry_nr->entry_nr,
1857 						GFP_KERNEL);
1858 		if (!adev->host_msix_entries) {
1859 			r = -ENOMEM;
1860 			goto msix_nr_out;
1861 		}
1862 		adev->guest_msix_entries = kzalloc(
1863 				sizeof(struct kvm_guest_msix_entry) *
1864 				entry_nr->entry_nr, GFP_KERNEL);
1865 		if (!adev->guest_msix_entries) {
1866 			kfree(adev->host_msix_entries);
1867 			r = -ENOMEM;
1868 			goto msix_nr_out;
1869 		}
1870 	} else /* Not allowed set MSI-X number twice */
1871 		r = -EINVAL;
1872 msix_nr_out:
1873 	mutex_unlock(&kvm->lock);
1874 	return r;
1875 }
1876 
1877 static int kvm_vm_ioctl_set_msix_entry(struct kvm *kvm,
1878 				       struct kvm_assigned_msix_entry *entry)
1879 {
1880 	int r = 0, i;
1881 	struct kvm_assigned_dev_kernel *adev;
1882 
1883 	mutex_lock(&kvm->lock);
1884 
1885 	adev = kvm_find_assigned_dev(&kvm->arch.assigned_dev_head,
1886 				      entry->assigned_dev_id);
1887 
1888 	if (!adev) {
1889 		r = -EINVAL;
1890 		goto msix_entry_out;
1891 	}
1892 
1893 	for (i = 0; i < adev->entries_nr; i++)
1894 		if (adev->guest_msix_entries[i].vector == 0 ||
1895 		    adev->guest_msix_entries[i].entry == entry->entry) {
1896 			adev->guest_msix_entries[i].entry = entry->entry;
1897 			adev->guest_msix_entries[i].vector = entry->gsi;
1898 			adev->host_msix_entries[i].entry = entry->entry;
1899 			break;
1900 		}
1901 	if (i == adev->entries_nr) {
1902 		r = -ENOSPC;
1903 		goto msix_entry_out;
1904 	}
1905 
1906 msix_entry_out:
1907 	mutex_unlock(&kvm->lock);
1908 
1909 	return r;
1910 }
1911 #endif
1912 
1913 static long kvm_vcpu_ioctl(struct file *filp,
1914 			   unsigned int ioctl, unsigned long arg)
1915 {
1916 	struct kvm_vcpu *vcpu = filp->private_data;
1917 	void __user *argp = (void __user *)arg;
1918 	int r;
1919 	struct kvm_fpu *fpu = NULL;
1920 	struct kvm_sregs *kvm_sregs = NULL;
1921 
1922 	if (vcpu->kvm->mm != current->mm)
1923 		return -EIO;
1924 	switch (ioctl) {
1925 	case KVM_RUN:
1926 		r = -EINVAL;
1927 		if (arg)
1928 			goto out;
1929 		r = kvm_arch_vcpu_ioctl_run(vcpu, vcpu->run);
1930 		break;
1931 	case KVM_GET_REGS: {
1932 		struct kvm_regs *kvm_regs;
1933 
1934 		r = -ENOMEM;
1935 		kvm_regs = kzalloc(sizeof(struct kvm_regs), GFP_KERNEL);
1936 		if (!kvm_regs)
1937 			goto out;
1938 		r = kvm_arch_vcpu_ioctl_get_regs(vcpu, kvm_regs);
1939 		if (r)
1940 			goto out_free1;
1941 		r = -EFAULT;
1942 		if (copy_to_user(argp, kvm_regs, sizeof(struct kvm_regs)))
1943 			goto out_free1;
1944 		r = 0;
1945 out_free1:
1946 		kfree(kvm_regs);
1947 		break;
1948 	}
1949 	case KVM_SET_REGS: {
1950 		struct kvm_regs *kvm_regs;
1951 
1952 		r = -ENOMEM;
1953 		kvm_regs = kzalloc(sizeof(struct kvm_regs), GFP_KERNEL);
1954 		if (!kvm_regs)
1955 			goto out;
1956 		r = -EFAULT;
1957 		if (copy_from_user(kvm_regs, argp, sizeof(struct kvm_regs)))
1958 			goto out_free2;
1959 		r = kvm_arch_vcpu_ioctl_set_regs(vcpu, kvm_regs);
1960 		if (r)
1961 			goto out_free2;
1962 		r = 0;
1963 out_free2:
1964 		kfree(kvm_regs);
1965 		break;
1966 	}
1967 	case KVM_GET_SREGS: {
1968 		kvm_sregs = kzalloc(sizeof(struct kvm_sregs), GFP_KERNEL);
1969 		r = -ENOMEM;
1970 		if (!kvm_sregs)
1971 			goto out;
1972 		r = kvm_arch_vcpu_ioctl_get_sregs(vcpu, kvm_sregs);
1973 		if (r)
1974 			goto out;
1975 		r = -EFAULT;
1976 		if (copy_to_user(argp, kvm_sregs, sizeof(struct kvm_sregs)))
1977 			goto out;
1978 		r = 0;
1979 		break;
1980 	}
1981 	case KVM_SET_SREGS: {
1982 		kvm_sregs = kmalloc(sizeof(struct kvm_sregs), GFP_KERNEL);
1983 		r = -ENOMEM;
1984 		if (!kvm_sregs)
1985 			goto out;
1986 		r = -EFAULT;
1987 		if (copy_from_user(kvm_sregs, argp, sizeof(struct kvm_sregs)))
1988 			goto out;
1989 		r = kvm_arch_vcpu_ioctl_set_sregs(vcpu, kvm_sregs);
1990 		if (r)
1991 			goto out;
1992 		r = 0;
1993 		break;
1994 	}
1995 	case KVM_GET_MP_STATE: {
1996 		struct kvm_mp_state mp_state;
1997 
1998 		r = kvm_arch_vcpu_ioctl_get_mpstate(vcpu, &mp_state);
1999 		if (r)
2000 			goto out;
2001 		r = -EFAULT;
2002 		if (copy_to_user(argp, &mp_state, sizeof mp_state))
2003 			goto out;
2004 		r = 0;
2005 		break;
2006 	}
2007 	case KVM_SET_MP_STATE: {
2008 		struct kvm_mp_state mp_state;
2009 
2010 		r = -EFAULT;
2011 		if (copy_from_user(&mp_state, argp, sizeof mp_state))
2012 			goto out;
2013 		r = kvm_arch_vcpu_ioctl_set_mpstate(vcpu, &mp_state);
2014 		if (r)
2015 			goto out;
2016 		r = 0;
2017 		break;
2018 	}
2019 	case KVM_TRANSLATE: {
2020 		struct kvm_translation tr;
2021 
2022 		r = -EFAULT;
2023 		if (copy_from_user(&tr, argp, sizeof tr))
2024 			goto out;
2025 		r = kvm_arch_vcpu_ioctl_translate(vcpu, &tr);
2026 		if (r)
2027 			goto out;
2028 		r = -EFAULT;
2029 		if (copy_to_user(argp, &tr, sizeof tr))
2030 			goto out;
2031 		r = 0;
2032 		break;
2033 	}
2034 	case KVM_SET_GUEST_DEBUG: {
2035 		struct kvm_guest_debug dbg;
2036 
2037 		r = -EFAULT;
2038 		if (copy_from_user(&dbg, argp, sizeof dbg))
2039 			goto out;
2040 		r = kvm_arch_vcpu_ioctl_set_guest_debug(vcpu, &dbg);
2041 		if (r)
2042 			goto out;
2043 		r = 0;
2044 		break;
2045 	}
2046 	case KVM_SET_SIGNAL_MASK: {
2047 		struct kvm_signal_mask __user *sigmask_arg = argp;
2048 		struct kvm_signal_mask kvm_sigmask;
2049 		sigset_t sigset, *p;
2050 
2051 		p = NULL;
2052 		if (argp) {
2053 			r = -EFAULT;
2054 			if (copy_from_user(&kvm_sigmask, argp,
2055 					   sizeof kvm_sigmask))
2056 				goto out;
2057 			r = -EINVAL;
2058 			if (kvm_sigmask.len != sizeof sigset)
2059 				goto out;
2060 			r = -EFAULT;
2061 			if (copy_from_user(&sigset, sigmask_arg->sigset,
2062 					   sizeof sigset))
2063 				goto out;
2064 			p = &sigset;
2065 		}
2066 		r = kvm_vcpu_ioctl_set_sigmask(vcpu, &sigset);
2067 		break;
2068 	}
2069 	case KVM_GET_FPU: {
2070 		fpu = kzalloc(sizeof(struct kvm_fpu), GFP_KERNEL);
2071 		r = -ENOMEM;
2072 		if (!fpu)
2073 			goto out;
2074 		r = kvm_arch_vcpu_ioctl_get_fpu(vcpu, fpu);
2075 		if (r)
2076 			goto out;
2077 		r = -EFAULT;
2078 		if (copy_to_user(argp, fpu, sizeof(struct kvm_fpu)))
2079 			goto out;
2080 		r = 0;
2081 		break;
2082 	}
2083 	case KVM_SET_FPU: {
2084 		fpu = kmalloc(sizeof(struct kvm_fpu), GFP_KERNEL);
2085 		r = -ENOMEM;
2086 		if (!fpu)
2087 			goto out;
2088 		r = -EFAULT;
2089 		if (copy_from_user(fpu, argp, sizeof(struct kvm_fpu)))
2090 			goto out;
2091 		r = kvm_arch_vcpu_ioctl_set_fpu(vcpu, fpu);
2092 		if (r)
2093 			goto out;
2094 		r = 0;
2095 		break;
2096 	}
2097 	default:
2098 		r = kvm_arch_vcpu_ioctl(filp, ioctl, arg);
2099 	}
2100 out:
2101 	kfree(fpu);
2102 	kfree(kvm_sregs);
2103 	return r;
2104 }
2105 
2106 static long kvm_vm_ioctl(struct file *filp,
2107 			   unsigned int ioctl, unsigned long arg)
2108 {
2109 	struct kvm *kvm = filp->private_data;
2110 	void __user *argp = (void __user *)arg;
2111 	int r;
2112 
2113 	if (kvm->mm != current->mm)
2114 		return -EIO;
2115 	switch (ioctl) {
2116 	case KVM_CREATE_VCPU:
2117 		r = kvm_vm_ioctl_create_vcpu(kvm, arg);
2118 		if (r < 0)
2119 			goto out;
2120 		break;
2121 	case KVM_SET_USER_MEMORY_REGION: {
2122 		struct kvm_userspace_memory_region kvm_userspace_mem;
2123 
2124 		r = -EFAULT;
2125 		if (copy_from_user(&kvm_userspace_mem, argp,
2126 						sizeof kvm_userspace_mem))
2127 			goto out;
2128 
2129 		r = kvm_vm_ioctl_set_memory_region(kvm, &kvm_userspace_mem, 1);
2130 		if (r)
2131 			goto out;
2132 		break;
2133 	}
2134 	case KVM_GET_DIRTY_LOG: {
2135 		struct kvm_dirty_log log;
2136 
2137 		r = -EFAULT;
2138 		if (copy_from_user(&log, argp, sizeof log))
2139 			goto out;
2140 		r = kvm_vm_ioctl_get_dirty_log(kvm, &log);
2141 		if (r)
2142 			goto out;
2143 		break;
2144 	}
2145 #ifdef KVM_COALESCED_MMIO_PAGE_OFFSET
2146 	case KVM_REGISTER_COALESCED_MMIO: {
2147 		struct kvm_coalesced_mmio_zone zone;
2148 		r = -EFAULT;
2149 		if (copy_from_user(&zone, argp, sizeof zone))
2150 			goto out;
2151 		r = -ENXIO;
2152 		r = kvm_vm_ioctl_register_coalesced_mmio(kvm, &zone);
2153 		if (r)
2154 			goto out;
2155 		r = 0;
2156 		break;
2157 	}
2158 	case KVM_UNREGISTER_COALESCED_MMIO: {
2159 		struct kvm_coalesced_mmio_zone zone;
2160 		r = -EFAULT;
2161 		if (copy_from_user(&zone, argp, sizeof zone))
2162 			goto out;
2163 		r = -ENXIO;
2164 		r = kvm_vm_ioctl_unregister_coalesced_mmio(kvm, &zone);
2165 		if (r)
2166 			goto out;
2167 		r = 0;
2168 		break;
2169 	}
2170 #endif
2171 #ifdef KVM_CAP_DEVICE_ASSIGNMENT
2172 	case KVM_ASSIGN_PCI_DEVICE: {
2173 		struct kvm_assigned_pci_dev assigned_dev;
2174 
2175 		r = -EFAULT;
2176 		if (copy_from_user(&assigned_dev, argp, sizeof assigned_dev))
2177 			goto out;
2178 		r = kvm_vm_ioctl_assign_device(kvm, &assigned_dev);
2179 		if (r)
2180 			goto out;
2181 		break;
2182 	}
2183 	case KVM_ASSIGN_IRQ: {
2184 		r = -EOPNOTSUPP;
2185 		break;
2186 	}
2187 #ifdef KVM_CAP_ASSIGN_DEV_IRQ
2188 	case KVM_ASSIGN_DEV_IRQ: {
2189 		struct kvm_assigned_irq assigned_irq;
2190 
2191 		r = -EFAULT;
2192 		if (copy_from_user(&assigned_irq, argp, sizeof assigned_irq))
2193 			goto out;
2194 		r = kvm_vm_ioctl_assign_irq(kvm, &assigned_irq);
2195 		if (r)
2196 			goto out;
2197 		break;
2198 	}
2199 	case KVM_DEASSIGN_DEV_IRQ: {
2200 		struct kvm_assigned_irq assigned_irq;
2201 
2202 		r = -EFAULT;
2203 		if (copy_from_user(&assigned_irq, argp, sizeof assigned_irq))
2204 			goto out;
2205 		r = kvm_vm_ioctl_deassign_dev_irq(kvm, &assigned_irq);
2206 		if (r)
2207 			goto out;
2208 		break;
2209 	}
2210 #endif
2211 #endif
2212 #ifdef KVM_CAP_DEVICE_DEASSIGNMENT
2213 	case KVM_DEASSIGN_PCI_DEVICE: {
2214 		struct kvm_assigned_pci_dev assigned_dev;
2215 
2216 		r = -EFAULT;
2217 		if (copy_from_user(&assigned_dev, argp, sizeof assigned_dev))
2218 			goto out;
2219 		r = kvm_vm_ioctl_deassign_device(kvm, &assigned_dev);
2220 		if (r)
2221 			goto out;
2222 		break;
2223 	}
2224 #endif
2225 #ifdef KVM_CAP_IRQ_ROUTING
2226 	case KVM_SET_GSI_ROUTING: {
2227 		struct kvm_irq_routing routing;
2228 		struct kvm_irq_routing __user *urouting;
2229 		struct kvm_irq_routing_entry *entries;
2230 
2231 		r = -EFAULT;
2232 		if (copy_from_user(&routing, argp, sizeof(routing)))
2233 			goto out;
2234 		r = -EINVAL;
2235 		if (routing.nr >= KVM_MAX_IRQ_ROUTES)
2236 			goto out;
2237 		if (routing.flags)
2238 			goto out;
2239 		r = -ENOMEM;
2240 		entries = vmalloc(routing.nr * sizeof(*entries));
2241 		if (!entries)
2242 			goto out;
2243 		r = -EFAULT;
2244 		urouting = argp;
2245 		if (copy_from_user(entries, urouting->entries,
2246 				   routing.nr * sizeof(*entries)))
2247 			goto out_free_irq_routing;
2248 		r = kvm_set_irq_routing(kvm, entries, routing.nr,
2249 					routing.flags);
2250 	out_free_irq_routing:
2251 		vfree(entries);
2252 		break;
2253 	}
2254 #endif /* KVM_CAP_IRQ_ROUTING */
2255 #ifdef __KVM_HAVE_MSIX
2256 	case KVM_ASSIGN_SET_MSIX_NR: {
2257 		struct kvm_assigned_msix_nr entry_nr;
2258 		r = -EFAULT;
2259 		if (copy_from_user(&entry_nr, argp, sizeof entry_nr))
2260 			goto out;
2261 		r = kvm_vm_ioctl_set_msix_nr(kvm, &entry_nr);
2262 		if (r)
2263 			goto out;
2264 		break;
2265 	}
2266 	case KVM_ASSIGN_SET_MSIX_ENTRY: {
2267 		struct kvm_assigned_msix_entry entry;
2268 		r = -EFAULT;
2269 		if (copy_from_user(&entry, argp, sizeof entry))
2270 			goto out;
2271 		r = kvm_vm_ioctl_set_msix_entry(kvm, &entry);
2272 		if (r)
2273 			goto out;
2274 		break;
2275 	}
2276 #endif
2277 	case KVM_IRQFD: {
2278 		struct kvm_irqfd data;
2279 
2280 		r = -EFAULT;
2281 		if (copy_from_user(&data, argp, sizeof data))
2282 			goto out;
2283 		r = kvm_irqfd(kvm, data.fd, data.gsi, data.flags);
2284 		break;
2285 	}
2286 	case KVM_IOEVENTFD: {
2287 		struct kvm_ioeventfd data;
2288 
2289 		r = -EFAULT;
2290 		if (copy_from_user(&data, argp, sizeof data))
2291 			goto out;
2292 		r = kvm_ioeventfd(kvm, &data);
2293 		break;
2294 	}
2295 #ifdef CONFIG_KVM_APIC_ARCHITECTURE
2296 	case KVM_SET_BOOT_CPU_ID:
2297 		r = 0;
2298 		mutex_lock(&kvm->lock);
2299 		if (atomic_read(&kvm->online_vcpus) != 0)
2300 			r = -EBUSY;
2301 		else
2302 			kvm->bsp_vcpu_id = arg;
2303 		mutex_unlock(&kvm->lock);
2304 		break;
2305 #endif
2306 	default:
2307 		r = kvm_arch_vm_ioctl(filp, ioctl, arg);
2308 	}
2309 out:
2310 	return r;
2311 }
2312 
2313 static int kvm_vm_fault(struct vm_area_struct *vma, struct vm_fault *vmf)
2314 {
2315 	struct page *page[1];
2316 	unsigned long addr;
2317 	int npages;
2318 	gfn_t gfn = vmf->pgoff;
2319 	struct kvm *kvm = vma->vm_file->private_data;
2320 
2321 	addr = gfn_to_hva(kvm, gfn);
2322 	if (kvm_is_error_hva(addr))
2323 		return VM_FAULT_SIGBUS;
2324 
2325 	npages = get_user_pages(current, current->mm, addr, 1, 1, 0, page,
2326 				NULL);
2327 	if (unlikely(npages != 1))
2328 		return VM_FAULT_SIGBUS;
2329 
2330 	vmf->page = page[0];
2331 	return 0;
2332 }
2333 
2334 static const struct vm_operations_struct kvm_vm_vm_ops = {
2335 	.fault = kvm_vm_fault,
2336 };
2337 
2338 static int kvm_vm_mmap(struct file *file, struct vm_area_struct *vma)
2339 {
2340 	vma->vm_ops = &kvm_vm_vm_ops;
2341 	return 0;
2342 }
2343 
2344 static struct file_operations kvm_vm_fops = {
2345 	.release        = kvm_vm_release,
2346 	.unlocked_ioctl = kvm_vm_ioctl,
2347 	.compat_ioctl   = kvm_vm_ioctl,
2348 	.mmap           = kvm_vm_mmap,
2349 };
2350 
2351 static int kvm_dev_ioctl_create_vm(void)
2352 {
2353 	int fd;
2354 	struct kvm *kvm;
2355 
2356 	kvm = kvm_create_vm();
2357 	if (IS_ERR(kvm))
2358 		return PTR_ERR(kvm);
2359 	fd = anon_inode_getfd("kvm-vm", &kvm_vm_fops, kvm, 0);
2360 	if (fd < 0)
2361 		kvm_put_kvm(kvm);
2362 
2363 	return fd;
2364 }
2365 
2366 static long kvm_dev_ioctl_check_extension_generic(long arg)
2367 {
2368 	switch (arg) {
2369 	case KVM_CAP_USER_MEMORY:
2370 	case KVM_CAP_DESTROY_MEMORY_REGION_WORKS:
2371 	case KVM_CAP_JOIN_MEMORY_REGIONS_WORKS:
2372 #ifdef CONFIG_KVM_APIC_ARCHITECTURE
2373 	case KVM_CAP_SET_BOOT_CPU_ID:
2374 #endif
2375 		return 1;
2376 #ifdef CONFIG_HAVE_KVM_IRQCHIP
2377 	case KVM_CAP_IRQ_ROUTING:
2378 		return KVM_MAX_IRQ_ROUTES;
2379 #endif
2380 	default:
2381 		break;
2382 	}
2383 	return kvm_dev_ioctl_check_extension(arg);
2384 }
2385 
2386 static long kvm_dev_ioctl(struct file *filp,
2387 			  unsigned int ioctl, unsigned long arg)
2388 {
2389 	long r = -EINVAL;
2390 
2391 	switch (ioctl) {
2392 	case KVM_GET_API_VERSION:
2393 		r = -EINVAL;
2394 		if (arg)
2395 			goto out;
2396 		r = KVM_API_VERSION;
2397 		break;
2398 	case KVM_CREATE_VM:
2399 		r = -EINVAL;
2400 		if (arg)
2401 			goto out;
2402 		r = kvm_dev_ioctl_create_vm();
2403 		break;
2404 	case KVM_CHECK_EXTENSION:
2405 		r = kvm_dev_ioctl_check_extension_generic(arg);
2406 		break;
2407 	case KVM_GET_VCPU_MMAP_SIZE:
2408 		r = -EINVAL;
2409 		if (arg)
2410 			goto out;
2411 		r = PAGE_SIZE;     /* struct kvm_run */
2412 #ifdef CONFIG_X86
2413 		r += PAGE_SIZE;    /* pio data page */
2414 #endif
2415 #ifdef KVM_COALESCED_MMIO_PAGE_OFFSET
2416 		r += PAGE_SIZE;    /* coalesced mmio ring page */
2417 #endif
2418 		break;
2419 	case KVM_TRACE_ENABLE:
2420 	case KVM_TRACE_PAUSE:
2421 	case KVM_TRACE_DISABLE:
2422 		r = -EOPNOTSUPP;
2423 		break;
2424 	default:
2425 		return kvm_arch_dev_ioctl(filp, ioctl, arg);
2426 	}
2427 out:
2428 	return r;
2429 }
2430 
2431 static struct file_operations kvm_chardev_ops = {
2432 	.unlocked_ioctl = kvm_dev_ioctl,
2433 	.compat_ioctl   = kvm_dev_ioctl,
2434 };
2435 
2436 static struct miscdevice kvm_dev = {
2437 	KVM_MINOR,
2438 	"kvm",
2439 	&kvm_chardev_ops,
2440 };
2441 
2442 static void hardware_enable(void *junk)
2443 {
2444 	int cpu = raw_smp_processor_id();
2445 
2446 	if (cpumask_test_cpu(cpu, cpus_hardware_enabled))
2447 		return;
2448 	cpumask_set_cpu(cpu, cpus_hardware_enabled);
2449 	kvm_arch_hardware_enable(NULL);
2450 }
2451 
2452 static void hardware_disable(void *junk)
2453 {
2454 	int cpu = raw_smp_processor_id();
2455 
2456 	if (!cpumask_test_cpu(cpu, cpus_hardware_enabled))
2457 		return;
2458 	cpumask_clear_cpu(cpu, cpus_hardware_enabled);
2459 	kvm_arch_hardware_disable(NULL);
2460 }
2461 
2462 static int kvm_cpu_hotplug(struct notifier_block *notifier, unsigned long val,
2463 			   void *v)
2464 {
2465 	int cpu = (long)v;
2466 
2467 	val &= ~CPU_TASKS_FROZEN;
2468 	switch (val) {
2469 	case CPU_DYING:
2470 		printk(KERN_INFO "kvm: disabling virtualization on CPU%d\n",
2471 		       cpu);
2472 		hardware_disable(NULL);
2473 		break;
2474 	case CPU_UP_CANCELED:
2475 		printk(KERN_INFO "kvm: disabling virtualization on CPU%d\n",
2476 		       cpu);
2477 		smp_call_function_single(cpu, hardware_disable, NULL, 1);
2478 		break;
2479 	case CPU_ONLINE:
2480 		printk(KERN_INFO "kvm: enabling virtualization on CPU%d\n",
2481 		       cpu);
2482 		smp_call_function_single(cpu, hardware_enable, NULL, 1);
2483 		break;
2484 	}
2485 	return NOTIFY_OK;
2486 }
2487 
2488 
2489 asmlinkage void kvm_handle_fault_on_reboot(void)
2490 {
2491 	if (kvm_rebooting)
2492 		/* spin while reset goes on */
2493 		while (true)
2494 			;
2495 	/* Fault while not rebooting.  We want the trace. */
2496 	BUG();
2497 }
2498 EXPORT_SYMBOL_GPL(kvm_handle_fault_on_reboot);
2499 
2500 static int kvm_reboot(struct notifier_block *notifier, unsigned long val,
2501 		      void *v)
2502 {
2503 	/*
2504 	 * Some (well, at least mine) BIOSes hang on reboot if
2505 	 * in vmx root mode.
2506 	 *
2507 	 * And Intel TXT required VMX off for all cpu when system shutdown.
2508 	 */
2509 	printk(KERN_INFO "kvm: exiting hardware virtualization\n");
2510 	kvm_rebooting = true;
2511 	on_each_cpu(hardware_disable, NULL, 1);
2512 	return NOTIFY_OK;
2513 }
2514 
2515 static struct notifier_block kvm_reboot_notifier = {
2516 	.notifier_call = kvm_reboot,
2517 	.priority = 0,
2518 };
2519 
2520 void kvm_io_bus_init(struct kvm_io_bus *bus)
2521 {
2522 	memset(bus, 0, sizeof(*bus));
2523 }
2524 
2525 void kvm_io_bus_destroy(struct kvm_io_bus *bus)
2526 {
2527 	int i;
2528 
2529 	for (i = 0; i < bus->dev_count; i++) {
2530 		struct kvm_io_device *pos = bus->devs[i];
2531 
2532 		kvm_iodevice_destructor(pos);
2533 	}
2534 }
2535 
2536 /* kvm_io_bus_write - called under kvm->slots_lock */
2537 int kvm_io_bus_write(struct kvm_io_bus *bus, gpa_t addr,
2538 		     int len, const void *val)
2539 {
2540 	int i;
2541 	for (i = 0; i < bus->dev_count; i++)
2542 		if (!kvm_iodevice_write(bus->devs[i], addr, len, val))
2543 			return 0;
2544 	return -EOPNOTSUPP;
2545 }
2546 
2547 /* kvm_io_bus_read - called under kvm->slots_lock */
2548 int kvm_io_bus_read(struct kvm_io_bus *bus, gpa_t addr, int len, void *val)
2549 {
2550 	int i;
2551 	for (i = 0; i < bus->dev_count; i++)
2552 		if (!kvm_iodevice_read(bus->devs[i], addr, len, val))
2553 			return 0;
2554 	return -EOPNOTSUPP;
2555 }
2556 
2557 int kvm_io_bus_register_dev(struct kvm *kvm, struct kvm_io_bus *bus,
2558 			     struct kvm_io_device *dev)
2559 {
2560 	int ret;
2561 
2562 	down_write(&kvm->slots_lock);
2563 	ret = __kvm_io_bus_register_dev(bus, dev);
2564 	up_write(&kvm->slots_lock);
2565 
2566 	return ret;
2567 }
2568 
2569 /* An unlocked version. Caller must have write lock on slots_lock. */
2570 int __kvm_io_bus_register_dev(struct kvm_io_bus *bus,
2571 			      struct kvm_io_device *dev)
2572 {
2573 	if (bus->dev_count > NR_IOBUS_DEVS-1)
2574 		return -ENOSPC;
2575 
2576 	bus->devs[bus->dev_count++] = dev;
2577 
2578 	return 0;
2579 }
2580 
2581 void kvm_io_bus_unregister_dev(struct kvm *kvm,
2582 			       struct kvm_io_bus *bus,
2583 			       struct kvm_io_device *dev)
2584 {
2585 	down_write(&kvm->slots_lock);
2586 	__kvm_io_bus_unregister_dev(bus, dev);
2587 	up_write(&kvm->slots_lock);
2588 }
2589 
2590 /* An unlocked version. Caller must have write lock on slots_lock. */
2591 void __kvm_io_bus_unregister_dev(struct kvm_io_bus *bus,
2592 				 struct kvm_io_device *dev)
2593 {
2594 	int i;
2595 
2596 	for (i = 0; i < bus->dev_count; i++)
2597 		if (bus->devs[i] == dev) {
2598 			bus->devs[i] = bus->devs[--bus->dev_count];
2599 			break;
2600 		}
2601 }
2602 
2603 static struct notifier_block kvm_cpu_notifier = {
2604 	.notifier_call = kvm_cpu_hotplug,
2605 	.priority = 20, /* must be > scheduler priority */
2606 };
2607 
2608 static int vm_stat_get(void *_offset, u64 *val)
2609 {
2610 	unsigned offset = (long)_offset;
2611 	struct kvm *kvm;
2612 
2613 	*val = 0;
2614 	spin_lock(&kvm_lock);
2615 	list_for_each_entry(kvm, &vm_list, vm_list)
2616 		*val += *(u32 *)((void *)kvm + offset);
2617 	spin_unlock(&kvm_lock);
2618 	return 0;
2619 }
2620 
2621 DEFINE_SIMPLE_ATTRIBUTE(vm_stat_fops, vm_stat_get, NULL, "%llu\n");
2622 
2623 static int vcpu_stat_get(void *_offset, u64 *val)
2624 {
2625 	unsigned offset = (long)_offset;
2626 	struct kvm *kvm;
2627 	struct kvm_vcpu *vcpu;
2628 	int i;
2629 
2630 	*val = 0;
2631 	spin_lock(&kvm_lock);
2632 	list_for_each_entry(kvm, &vm_list, vm_list)
2633 		kvm_for_each_vcpu(i, vcpu, kvm)
2634 			*val += *(u32 *)((void *)vcpu + offset);
2635 
2636 	spin_unlock(&kvm_lock);
2637 	return 0;
2638 }
2639 
2640 DEFINE_SIMPLE_ATTRIBUTE(vcpu_stat_fops, vcpu_stat_get, NULL, "%llu\n");
2641 
2642 static const struct file_operations *stat_fops[] = {
2643 	[KVM_STAT_VCPU] = &vcpu_stat_fops,
2644 	[KVM_STAT_VM]   = &vm_stat_fops,
2645 };
2646 
2647 static void kvm_init_debug(void)
2648 {
2649 	struct kvm_stats_debugfs_item *p;
2650 
2651 	kvm_debugfs_dir = debugfs_create_dir("kvm", NULL);
2652 	for (p = debugfs_entries; p->name; ++p)
2653 		p->dentry = debugfs_create_file(p->name, 0444, kvm_debugfs_dir,
2654 						(void *)(long)p->offset,
2655 						stat_fops[p->kind]);
2656 }
2657 
2658 static void kvm_exit_debug(void)
2659 {
2660 	struct kvm_stats_debugfs_item *p;
2661 
2662 	for (p = debugfs_entries; p->name; ++p)
2663 		debugfs_remove(p->dentry);
2664 	debugfs_remove(kvm_debugfs_dir);
2665 }
2666 
2667 static int kvm_suspend(struct sys_device *dev, pm_message_t state)
2668 {
2669 	hardware_disable(NULL);
2670 	return 0;
2671 }
2672 
2673 static int kvm_resume(struct sys_device *dev)
2674 {
2675 	hardware_enable(NULL);
2676 	return 0;
2677 }
2678 
2679 static struct sysdev_class kvm_sysdev_class = {
2680 	.name = "kvm",
2681 	.suspend = kvm_suspend,
2682 	.resume = kvm_resume,
2683 };
2684 
2685 static struct sys_device kvm_sysdev = {
2686 	.id = 0,
2687 	.cls = &kvm_sysdev_class,
2688 };
2689 
2690 struct page *bad_page;
2691 pfn_t bad_pfn;
2692 
2693 static inline
2694 struct kvm_vcpu *preempt_notifier_to_vcpu(struct preempt_notifier *pn)
2695 {
2696 	return container_of(pn, struct kvm_vcpu, preempt_notifier);
2697 }
2698 
2699 static void kvm_sched_in(struct preempt_notifier *pn, int cpu)
2700 {
2701 	struct kvm_vcpu *vcpu = preempt_notifier_to_vcpu(pn);
2702 
2703 	kvm_arch_vcpu_load(vcpu, cpu);
2704 }
2705 
2706 static void kvm_sched_out(struct preempt_notifier *pn,
2707 			  struct task_struct *next)
2708 {
2709 	struct kvm_vcpu *vcpu = preempt_notifier_to_vcpu(pn);
2710 
2711 	kvm_arch_vcpu_put(vcpu);
2712 }
2713 
2714 int kvm_init(void *opaque, unsigned int vcpu_size,
2715 		  struct module *module)
2716 {
2717 	int r;
2718 	int cpu;
2719 
2720 	r = kvm_arch_init(opaque);
2721 	if (r)
2722 		goto out_fail;
2723 
2724 	bad_page = alloc_page(GFP_KERNEL | __GFP_ZERO);
2725 
2726 	if (bad_page == NULL) {
2727 		r = -ENOMEM;
2728 		goto out;
2729 	}
2730 
2731 	bad_pfn = page_to_pfn(bad_page);
2732 
2733 	if (!zalloc_cpumask_var(&cpus_hardware_enabled, GFP_KERNEL)) {
2734 		r = -ENOMEM;
2735 		goto out_free_0;
2736 	}
2737 
2738 	r = kvm_arch_hardware_setup();
2739 	if (r < 0)
2740 		goto out_free_0a;
2741 
2742 	for_each_online_cpu(cpu) {
2743 		smp_call_function_single(cpu,
2744 				kvm_arch_check_processor_compat,
2745 				&r, 1);
2746 		if (r < 0)
2747 			goto out_free_1;
2748 	}
2749 
2750 	on_each_cpu(hardware_enable, NULL, 1);
2751 	r = register_cpu_notifier(&kvm_cpu_notifier);
2752 	if (r)
2753 		goto out_free_2;
2754 	register_reboot_notifier(&kvm_reboot_notifier);
2755 
2756 	r = sysdev_class_register(&kvm_sysdev_class);
2757 	if (r)
2758 		goto out_free_3;
2759 
2760 	r = sysdev_register(&kvm_sysdev);
2761 	if (r)
2762 		goto out_free_4;
2763 
2764 	/* A kmem cache lets us meet the alignment requirements of fx_save. */
2765 	kvm_vcpu_cache = kmem_cache_create("kvm_vcpu", vcpu_size,
2766 					   __alignof__(struct kvm_vcpu),
2767 					   0, NULL);
2768 	if (!kvm_vcpu_cache) {
2769 		r = -ENOMEM;
2770 		goto out_free_5;
2771 	}
2772 
2773 	kvm_chardev_ops.owner = module;
2774 	kvm_vm_fops.owner = module;
2775 	kvm_vcpu_fops.owner = module;
2776 
2777 	r = misc_register(&kvm_dev);
2778 	if (r) {
2779 		printk(KERN_ERR "kvm: misc device register failed\n");
2780 		goto out_free;
2781 	}
2782 
2783 	kvm_preempt_ops.sched_in = kvm_sched_in;
2784 	kvm_preempt_ops.sched_out = kvm_sched_out;
2785 
2786 	kvm_init_debug();
2787 
2788 	return 0;
2789 
2790 out_free:
2791 	kmem_cache_destroy(kvm_vcpu_cache);
2792 out_free_5:
2793 	sysdev_unregister(&kvm_sysdev);
2794 out_free_4:
2795 	sysdev_class_unregister(&kvm_sysdev_class);
2796 out_free_3:
2797 	unregister_reboot_notifier(&kvm_reboot_notifier);
2798 	unregister_cpu_notifier(&kvm_cpu_notifier);
2799 out_free_2:
2800 	on_each_cpu(hardware_disable, NULL, 1);
2801 out_free_1:
2802 	kvm_arch_hardware_unsetup();
2803 out_free_0a:
2804 	free_cpumask_var(cpus_hardware_enabled);
2805 out_free_0:
2806 	__free_page(bad_page);
2807 out:
2808 	kvm_arch_exit();
2809 out_fail:
2810 	return r;
2811 }
2812 EXPORT_SYMBOL_GPL(kvm_init);
2813 
2814 void kvm_exit(void)
2815 {
2816 	tracepoint_synchronize_unregister();
2817 	kvm_exit_debug();
2818 	misc_deregister(&kvm_dev);
2819 	kmem_cache_destroy(kvm_vcpu_cache);
2820 	sysdev_unregister(&kvm_sysdev);
2821 	sysdev_class_unregister(&kvm_sysdev_class);
2822 	unregister_reboot_notifier(&kvm_reboot_notifier);
2823 	unregister_cpu_notifier(&kvm_cpu_notifier);
2824 	on_each_cpu(hardware_disable, NULL, 1);
2825 	kvm_arch_hardware_unsetup();
2826 	kvm_arch_exit();
2827 	free_cpumask_var(cpus_hardware_enabled);
2828 	__free_page(bad_page);
2829 }
2830 EXPORT_SYMBOL_GPL(kvm_exit);
2831