xref: /linux/virt/kvm/kvm_main.c (revision b233b28eac0cc37d07c2d007ea08c86c778c5af4)
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 CONFIG_X86
51 #include <asm/msidef.h>
52 #endif
53 
54 #ifdef KVM_COALESCED_MMIO_PAGE_OFFSET
55 #include "coalesced_mmio.h"
56 #endif
57 
58 #ifdef KVM_CAP_DEVICE_ASSIGNMENT
59 #include <linux/pci.h>
60 #include <linux/interrupt.h>
61 #include "irq.h"
62 #endif
63 
64 MODULE_AUTHOR("Qumranet");
65 MODULE_LICENSE("GPL");
66 
67 static int msi2intx = 1;
68 module_param(msi2intx, bool, 0);
69 
70 DEFINE_SPINLOCK(kvm_lock);
71 LIST_HEAD(vm_list);
72 
73 static cpumask_var_t cpus_hardware_enabled;
74 
75 struct kmem_cache *kvm_vcpu_cache;
76 EXPORT_SYMBOL_GPL(kvm_vcpu_cache);
77 
78 static __read_mostly struct preempt_ops kvm_preempt_ops;
79 
80 struct dentry *kvm_debugfs_dir;
81 
82 static long kvm_vcpu_ioctl(struct file *file, unsigned int ioctl,
83 			   unsigned long arg);
84 
85 static bool kvm_rebooting;
86 
87 #ifdef KVM_CAP_DEVICE_ASSIGNMENT
88 
89 #ifdef CONFIG_X86
90 static void assigned_device_msi_dispatch(struct kvm_assigned_dev_kernel *dev)
91 {
92 	int vcpu_id;
93 	struct kvm_vcpu *vcpu;
94 	struct kvm_ioapic *ioapic = ioapic_irqchip(dev->kvm);
95 	int dest_id = (dev->guest_msi.address_lo & MSI_ADDR_DEST_ID_MASK)
96 			>> MSI_ADDR_DEST_ID_SHIFT;
97 	int vector = (dev->guest_msi.data & MSI_DATA_VECTOR_MASK)
98 			>> MSI_DATA_VECTOR_SHIFT;
99 	int dest_mode = test_bit(MSI_ADDR_DEST_MODE_SHIFT,
100 				(unsigned long *)&dev->guest_msi.address_lo);
101 	int trig_mode = test_bit(MSI_DATA_TRIGGER_SHIFT,
102 				(unsigned long *)&dev->guest_msi.data);
103 	int delivery_mode = test_bit(MSI_DATA_DELIVERY_MODE_SHIFT,
104 				(unsigned long *)&dev->guest_msi.data);
105 	u32 deliver_bitmask;
106 
107 	BUG_ON(!ioapic);
108 
109 	deliver_bitmask = kvm_ioapic_get_delivery_bitmask(ioapic,
110 				dest_id, dest_mode);
111 	/* IOAPIC delivery mode value is the same as MSI here */
112 	switch (delivery_mode) {
113 	case IOAPIC_LOWEST_PRIORITY:
114 		vcpu = kvm_get_lowest_prio_vcpu(ioapic->kvm, vector,
115 				deliver_bitmask);
116 		if (vcpu != NULL)
117 			kvm_apic_set_irq(vcpu, vector, trig_mode);
118 		else
119 			printk(KERN_INFO "kvm: null lowest priority vcpu!\n");
120 		break;
121 	case IOAPIC_FIXED:
122 		for (vcpu_id = 0; deliver_bitmask != 0; vcpu_id++) {
123 			if (!(deliver_bitmask & (1 << vcpu_id)))
124 				continue;
125 			deliver_bitmask &= ~(1 << vcpu_id);
126 			vcpu = ioapic->kvm->vcpus[vcpu_id];
127 			if (vcpu)
128 				kvm_apic_set_irq(vcpu, vector, trig_mode);
129 		}
130 		break;
131 	default:
132 		printk(KERN_INFO "kvm: unsupported MSI delivery mode\n");
133 	}
134 }
135 #else
136 static void assigned_device_msi_dispatch(struct kvm_assigned_dev_kernel *dev) {}
137 #endif
138 
139 static struct kvm_assigned_dev_kernel *kvm_find_assigned_dev(struct list_head *head,
140 						      int assigned_dev_id)
141 {
142 	struct list_head *ptr;
143 	struct kvm_assigned_dev_kernel *match;
144 
145 	list_for_each(ptr, head) {
146 		match = list_entry(ptr, struct kvm_assigned_dev_kernel, list);
147 		if (match->assigned_dev_id == assigned_dev_id)
148 			return match;
149 	}
150 	return NULL;
151 }
152 
153 static void kvm_assigned_dev_interrupt_work_handler(struct work_struct *work)
154 {
155 	struct kvm_assigned_dev_kernel *assigned_dev;
156 
157 	assigned_dev = container_of(work, struct kvm_assigned_dev_kernel,
158 				    interrupt_work);
159 
160 	/* This is taken to safely inject irq inside the guest. When
161 	 * the interrupt injection (or the ioapic code) uses a
162 	 * finer-grained lock, update this
163 	 */
164 	mutex_lock(&assigned_dev->kvm->lock);
165 	if (assigned_dev->irq_requested_type & KVM_ASSIGNED_DEV_GUEST_INTX)
166 		kvm_set_irq(assigned_dev->kvm,
167 			    assigned_dev->irq_source_id,
168 			    assigned_dev->guest_irq, 1);
169 	else if (assigned_dev->irq_requested_type &
170 				KVM_ASSIGNED_DEV_GUEST_MSI) {
171 		assigned_device_msi_dispatch(assigned_dev);
172 		enable_irq(assigned_dev->host_irq);
173 		assigned_dev->host_irq_disabled = false;
174 	}
175 	mutex_unlock(&assigned_dev->kvm->lock);
176 	kvm_put_kvm(assigned_dev->kvm);
177 }
178 
179 static irqreturn_t kvm_assigned_dev_intr(int irq, void *dev_id)
180 {
181 	struct kvm_assigned_dev_kernel *assigned_dev =
182 		(struct kvm_assigned_dev_kernel *) dev_id;
183 
184 	kvm_get_kvm(assigned_dev->kvm);
185 
186 	schedule_work(&assigned_dev->interrupt_work);
187 
188 	disable_irq_nosync(irq);
189 	assigned_dev->host_irq_disabled = true;
190 
191 	return IRQ_HANDLED;
192 }
193 
194 /* Ack the irq line for an assigned device */
195 static void kvm_assigned_dev_ack_irq(struct kvm_irq_ack_notifier *kian)
196 {
197 	struct kvm_assigned_dev_kernel *dev;
198 
199 	if (kian->gsi == -1)
200 		return;
201 
202 	dev = container_of(kian, struct kvm_assigned_dev_kernel,
203 			   ack_notifier);
204 
205 	kvm_set_irq(dev->kvm, dev->irq_source_id, dev->guest_irq, 0);
206 
207 	/* The guest irq may be shared so this ack may be
208 	 * from another device.
209 	 */
210 	if (dev->host_irq_disabled) {
211 		enable_irq(dev->host_irq);
212 		dev->host_irq_disabled = false;
213 	}
214 }
215 
216 static void kvm_free_assigned_irq(struct kvm *kvm,
217 				  struct kvm_assigned_dev_kernel *assigned_dev)
218 {
219 	if (!irqchip_in_kernel(kvm))
220 		return;
221 
222 	kvm_unregister_irq_ack_notifier(&assigned_dev->ack_notifier);
223 
224 	if (assigned_dev->irq_source_id != -1)
225 		kvm_free_irq_source_id(kvm, assigned_dev->irq_source_id);
226 	assigned_dev->irq_source_id = -1;
227 
228 	if (!assigned_dev->irq_requested_type)
229 		return;
230 
231 	if (cancel_work_sync(&assigned_dev->interrupt_work))
232 		/* We had pending work. That means we will have to take
233 		 * care of kvm_put_kvm.
234 		 */
235 		kvm_put_kvm(kvm);
236 
237 	free_irq(assigned_dev->host_irq, (void *)assigned_dev);
238 
239 	if (assigned_dev->irq_requested_type & KVM_ASSIGNED_DEV_HOST_MSI)
240 		pci_disable_msi(assigned_dev->dev);
241 
242 	assigned_dev->irq_requested_type = 0;
243 }
244 
245 
246 static void kvm_free_assigned_device(struct kvm *kvm,
247 				     struct kvm_assigned_dev_kernel
248 				     *assigned_dev)
249 {
250 	kvm_free_assigned_irq(kvm, assigned_dev);
251 
252 	pci_reset_function(assigned_dev->dev);
253 
254 	pci_release_regions(assigned_dev->dev);
255 	pci_disable_device(assigned_dev->dev);
256 	pci_dev_put(assigned_dev->dev);
257 
258 	list_del(&assigned_dev->list);
259 	kfree(assigned_dev);
260 }
261 
262 void kvm_free_all_assigned_devices(struct kvm *kvm)
263 {
264 	struct list_head *ptr, *ptr2;
265 	struct kvm_assigned_dev_kernel *assigned_dev;
266 
267 	list_for_each_safe(ptr, ptr2, &kvm->arch.assigned_dev_head) {
268 		assigned_dev = list_entry(ptr,
269 					  struct kvm_assigned_dev_kernel,
270 					  list);
271 
272 		kvm_free_assigned_device(kvm, assigned_dev);
273 	}
274 }
275 
276 static int assigned_device_update_intx(struct kvm *kvm,
277 			struct kvm_assigned_dev_kernel *adev,
278 			struct kvm_assigned_irq *airq)
279 {
280 	adev->guest_irq = airq->guest_irq;
281 	adev->ack_notifier.gsi = airq->guest_irq;
282 
283 	if (adev->irq_requested_type & KVM_ASSIGNED_DEV_HOST_INTX)
284 		return 0;
285 
286 	if (irqchip_in_kernel(kvm)) {
287 		if (!msi2intx &&
288 		    adev->irq_requested_type & KVM_ASSIGNED_DEV_HOST_MSI) {
289 			free_irq(adev->host_irq, (void *)kvm);
290 			pci_disable_msi(adev->dev);
291 		}
292 
293 		if (!capable(CAP_SYS_RAWIO))
294 			return -EPERM;
295 
296 		if (airq->host_irq)
297 			adev->host_irq = airq->host_irq;
298 		else
299 			adev->host_irq = adev->dev->irq;
300 
301 		/* Even though this is PCI, we don't want to use shared
302 		 * interrupts. Sharing host devices with guest-assigned devices
303 		 * on the same interrupt line is not a happy situation: there
304 		 * are going to be long delays in accepting, acking, etc.
305 		 */
306 		if (request_irq(adev->host_irq, kvm_assigned_dev_intr,
307 				0, "kvm_assigned_intx_device", (void *)adev))
308 			return -EIO;
309 	}
310 
311 	adev->irq_requested_type = KVM_ASSIGNED_DEV_GUEST_INTX |
312 				   KVM_ASSIGNED_DEV_HOST_INTX;
313 	return 0;
314 }
315 
316 #ifdef CONFIG_X86
317 static int assigned_device_update_msi(struct kvm *kvm,
318 			struct kvm_assigned_dev_kernel *adev,
319 			struct kvm_assigned_irq *airq)
320 {
321 	int r;
322 
323 	if (airq->flags & KVM_DEV_IRQ_ASSIGN_ENABLE_MSI) {
324 		/* x86 don't care upper address of guest msi message addr */
325 		adev->irq_requested_type |= KVM_ASSIGNED_DEV_GUEST_MSI;
326 		adev->irq_requested_type &= ~KVM_ASSIGNED_DEV_GUEST_INTX;
327 		adev->guest_msi.address_lo = airq->guest_msi.addr_lo;
328 		adev->guest_msi.data = airq->guest_msi.data;
329 		adev->ack_notifier.gsi = -1;
330 	} else if (msi2intx) {
331 		adev->irq_requested_type |= KVM_ASSIGNED_DEV_GUEST_INTX;
332 		adev->irq_requested_type &= ~KVM_ASSIGNED_DEV_GUEST_MSI;
333 		adev->guest_irq = airq->guest_irq;
334 		adev->ack_notifier.gsi = airq->guest_irq;
335 	}
336 
337 	if (adev->irq_requested_type & KVM_ASSIGNED_DEV_HOST_MSI)
338 		return 0;
339 
340 	if (irqchip_in_kernel(kvm)) {
341 		if (!msi2intx) {
342 			if (adev->irq_requested_type &
343 					KVM_ASSIGNED_DEV_HOST_INTX)
344 				free_irq(adev->host_irq, (void *)adev);
345 
346 			r = pci_enable_msi(adev->dev);
347 			if (r)
348 				return r;
349 		}
350 
351 		adev->host_irq = adev->dev->irq;
352 		if (request_irq(adev->host_irq, kvm_assigned_dev_intr, 0,
353 				"kvm_assigned_msi_device", (void *)adev))
354 			return -EIO;
355 	}
356 
357 	if (!msi2intx)
358 		adev->irq_requested_type = KVM_ASSIGNED_DEV_GUEST_MSI;
359 
360 	adev->irq_requested_type |= KVM_ASSIGNED_DEV_HOST_MSI;
361 	return 0;
362 }
363 #endif
364 
365 static int kvm_vm_ioctl_assign_irq(struct kvm *kvm,
366 				   struct kvm_assigned_irq
367 				   *assigned_irq)
368 {
369 	int r = 0;
370 	struct kvm_assigned_dev_kernel *match;
371 
372 	mutex_lock(&kvm->lock);
373 
374 	match = kvm_find_assigned_dev(&kvm->arch.assigned_dev_head,
375 				      assigned_irq->assigned_dev_id);
376 	if (!match) {
377 		mutex_unlock(&kvm->lock);
378 		return -EINVAL;
379 	}
380 
381 	if (!match->irq_requested_type) {
382 		INIT_WORK(&match->interrupt_work,
383 				kvm_assigned_dev_interrupt_work_handler);
384 		if (irqchip_in_kernel(kvm)) {
385 			/* Register ack nofitier */
386 			match->ack_notifier.gsi = -1;
387 			match->ack_notifier.irq_acked =
388 					kvm_assigned_dev_ack_irq;
389 			kvm_register_irq_ack_notifier(kvm,
390 					&match->ack_notifier);
391 
392 			/* Request IRQ source ID */
393 			r = kvm_request_irq_source_id(kvm);
394 			if (r < 0)
395 				goto out_release;
396 			else
397 				match->irq_source_id = r;
398 
399 #ifdef CONFIG_X86
400 			/* Determine host device irq type, we can know the
401 			 * result from dev->msi_enabled */
402 			if (msi2intx)
403 				pci_enable_msi(match->dev);
404 #endif
405 		}
406 	}
407 
408 	if ((!msi2intx &&
409 	     (assigned_irq->flags & KVM_DEV_IRQ_ASSIGN_ENABLE_MSI)) ||
410 	    (msi2intx && match->dev->msi_enabled)) {
411 #ifdef CONFIG_X86
412 		r = assigned_device_update_msi(kvm, match, assigned_irq);
413 		if (r) {
414 			printk(KERN_WARNING "kvm: failed to enable "
415 					"MSI device!\n");
416 			goto out_release;
417 		}
418 #else
419 		r = -ENOTTY;
420 #endif
421 	} else if (assigned_irq->host_irq == 0 && match->dev->irq == 0) {
422 		/* Host device IRQ 0 means don't support INTx */
423 		if (!msi2intx) {
424 			printk(KERN_WARNING
425 			       "kvm: wait device to enable MSI!\n");
426 			r = 0;
427 		} else {
428 			printk(KERN_WARNING
429 			       "kvm: failed to enable MSI device!\n");
430 			r = -ENOTTY;
431 			goto out_release;
432 		}
433 	} else {
434 		/* Non-sharing INTx mode */
435 		r = assigned_device_update_intx(kvm, match, assigned_irq);
436 		if (r) {
437 			printk(KERN_WARNING "kvm: failed to enable "
438 					"INTx device!\n");
439 			goto out_release;
440 		}
441 	}
442 
443 	mutex_unlock(&kvm->lock);
444 	return r;
445 out_release:
446 	mutex_unlock(&kvm->lock);
447 	kvm_free_assigned_device(kvm, match);
448 	return r;
449 }
450 
451 static int kvm_vm_ioctl_assign_device(struct kvm *kvm,
452 				      struct kvm_assigned_pci_dev *assigned_dev)
453 {
454 	int r = 0;
455 	struct kvm_assigned_dev_kernel *match;
456 	struct pci_dev *dev;
457 
458 	mutex_lock(&kvm->lock);
459 
460 	match = kvm_find_assigned_dev(&kvm->arch.assigned_dev_head,
461 				      assigned_dev->assigned_dev_id);
462 	if (match) {
463 		/* device already assigned */
464 		r = -EINVAL;
465 		goto out;
466 	}
467 
468 	match = kzalloc(sizeof(struct kvm_assigned_dev_kernel), GFP_KERNEL);
469 	if (match == NULL) {
470 		printk(KERN_INFO "%s: Couldn't allocate memory\n",
471 		       __func__);
472 		r = -ENOMEM;
473 		goto out;
474 	}
475 	dev = pci_get_bus_and_slot(assigned_dev->busnr,
476 				   assigned_dev->devfn);
477 	if (!dev) {
478 		printk(KERN_INFO "%s: host device not found\n", __func__);
479 		r = -EINVAL;
480 		goto out_free;
481 	}
482 	if (pci_enable_device(dev)) {
483 		printk(KERN_INFO "%s: Could not enable PCI device\n", __func__);
484 		r = -EBUSY;
485 		goto out_put;
486 	}
487 	r = pci_request_regions(dev, "kvm_assigned_device");
488 	if (r) {
489 		printk(KERN_INFO "%s: Could not get access to device regions\n",
490 		       __func__);
491 		goto out_disable;
492 	}
493 
494 	pci_reset_function(dev);
495 
496 	match->assigned_dev_id = assigned_dev->assigned_dev_id;
497 	match->host_busnr = assigned_dev->busnr;
498 	match->host_devfn = assigned_dev->devfn;
499 	match->flags = assigned_dev->flags;
500 	match->dev = dev;
501 	match->irq_source_id = -1;
502 	match->kvm = kvm;
503 
504 	list_add(&match->list, &kvm->arch.assigned_dev_head);
505 
506 	if (assigned_dev->flags & KVM_DEV_ASSIGN_ENABLE_IOMMU) {
507 		if (!kvm->arch.iommu_domain) {
508 			r = kvm_iommu_map_guest(kvm);
509 			if (r)
510 				goto out_list_del;
511 		}
512 		r = kvm_assign_device(kvm, match);
513 		if (r)
514 			goto out_list_del;
515 	}
516 
517 out:
518 	mutex_unlock(&kvm->lock);
519 	return r;
520 out_list_del:
521 	list_del(&match->list);
522 	pci_release_regions(dev);
523 out_disable:
524 	pci_disable_device(dev);
525 out_put:
526 	pci_dev_put(dev);
527 out_free:
528 	kfree(match);
529 	mutex_unlock(&kvm->lock);
530 	return r;
531 }
532 #endif
533 
534 #ifdef KVM_CAP_DEVICE_DEASSIGNMENT
535 static int kvm_vm_ioctl_deassign_device(struct kvm *kvm,
536 		struct kvm_assigned_pci_dev *assigned_dev)
537 {
538 	int r = 0;
539 	struct kvm_assigned_dev_kernel *match;
540 
541 	mutex_lock(&kvm->lock);
542 
543 	match = kvm_find_assigned_dev(&kvm->arch.assigned_dev_head,
544 				      assigned_dev->assigned_dev_id);
545 	if (!match) {
546 		printk(KERN_INFO "%s: device hasn't been assigned before, "
547 		  "so cannot be deassigned\n", __func__);
548 		r = -EINVAL;
549 		goto out;
550 	}
551 
552 	if (assigned_dev->flags & KVM_DEV_ASSIGN_ENABLE_IOMMU)
553 		kvm_deassign_device(kvm, match);
554 
555 	kvm_free_assigned_device(kvm, match);
556 
557 out:
558 	mutex_unlock(&kvm->lock);
559 	return r;
560 }
561 #endif
562 
563 static inline int valid_vcpu(int n)
564 {
565 	return likely(n >= 0 && n < KVM_MAX_VCPUS);
566 }
567 
568 inline int kvm_is_mmio_pfn(pfn_t pfn)
569 {
570 	if (pfn_valid(pfn))
571 		return PageReserved(pfn_to_page(pfn));
572 
573 	return true;
574 }
575 
576 /*
577  * Switches to specified vcpu, until a matching vcpu_put()
578  */
579 void vcpu_load(struct kvm_vcpu *vcpu)
580 {
581 	int cpu;
582 
583 	mutex_lock(&vcpu->mutex);
584 	cpu = get_cpu();
585 	preempt_notifier_register(&vcpu->preempt_notifier);
586 	kvm_arch_vcpu_load(vcpu, cpu);
587 	put_cpu();
588 }
589 
590 void vcpu_put(struct kvm_vcpu *vcpu)
591 {
592 	preempt_disable();
593 	kvm_arch_vcpu_put(vcpu);
594 	preempt_notifier_unregister(&vcpu->preempt_notifier);
595 	preempt_enable();
596 	mutex_unlock(&vcpu->mutex);
597 }
598 
599 static void ack_flush(void *_completed)
600 {
601 }
602 
603 static bool make_all_cpus_request(struct kvm *kvm, unsigned int req)
604 {
605 	int i, cpu, me;
606 	cpumask_var_t cpus;
607 	bool called = true;
608 	struct kvm_vcpu *vcpu;
609 
610 	if (alloc_cpumask_var(&cpus, GFP_ATOMIC))
611 		cpumask_clear(cpus);
612 
613 	me = get_cpu();
614 	for (i = 0; i < KVM_MAX_VCPUS; ++i) {
615 		vcpu = kvm->vcpus[i];
616 		if (!vcpu)
617 			continue;
618 		if (test_and_set_bit(req, &vcpu->requests))
619 			continue;
620 		cpu = vcpu->cpu;
621 		if (cpus != NULL && cpu != -1 && cpu != me)
622 			cpumask_set_cpu(cpu, cpus);
623 	}
624 	if (unlikely(cpus == NULL))
625 		smp_call_function_many(cpu_online_mask, ack_flush, NULL, 1);
626 	else if (!cpumask_empty(cpus))
627 		smp_call_function_many(cpus, ack_flush, NULL, 1);
628 	else
629 		called = false;
630 	put_cpu();
631 	free_cpumask_var(cpus);
632 	return called;
633 }
634 
635 void kvm_flush_remote_tlbs(struct kvm *kvm)
636 {
637 	if (make_all_cpus_request(kvm, KVM_REQ_TLB_FLUSH))
638 		++kvm->stat.remote_tlb_flush;
639 }
640 
641 void kvm_reload_remote_mmus(struct kvm *kvm)
642 {
643 	make_all_cpus_request(kvm, KVM_REQ_MMU_RELOAD);
644 }
645 
646 int kvm_vcpu_init(struct kvm_vcpu *vcpu, struct kvm *kvm, unsigned id)
647 {
648 	struct page *page;
649 	int r;
650 
651 	mutex_init(&vcpu->mutex);
652 	vcpu->cpu = -1;
653 	vcpu->kvm = kvm;
654 	vcpu->vcpu_id = id;
655 	init_waitqueue_head(&vcpu->wq);
656 
657 	page = alloc_page(GFP_KERNEL | __GFP_ZERO);
658 	if (!page) {
659 		r = -ENOMEM;
660 		goto fail;
661 	}
662 	vcpu->run = page_address(page);
663 
664 	r = kvm_arch_vcpu_init(vcpu);
665 	if (r < 0)
666 		goto fail_free_run;
667 	return 0;
668 
669 fail_free_run:
670 	free_page((unsigned long)vcpu->run);
671 fail:
672 	return r;
673 }
674 EXPORT_SYMBOL_GPL(kvm_vcpu_init);
675 
676 void kvm_vcpu_uninit(struct kvm_vcpu *vcpu)
677 {
678 	kvm_arch_vcpu_uninit(vcpu);
679 	free_page((unsigned long)vcpu->run);
680 }
681 EXPORT_SYMBOL_GPL(kvm_vcpu_uninit);
682 
683 #if defined(CONFIG_MMU_NOTIFIER) && defined(KVM_ARCH_WANT_MMU_NOTIFIER)
684 static inline struct kvm *mmu_notifier_to_kvm(struct mmu_notifier *mn)
685 {
686 	return container_of(mn, struct kvm, mmu_notifier);
687 }
688 
689 static void kvm_mmu_notifier_invalidate_page(struct mmu_notifier *mn,
690 					     struct mm_struct *mm,
691 					     unsigned long address)
692 {
693 	struct kvm *kvm = mmu_notifier_to_kvm(mn);
694 	int need_tlb_flush;
695 
696 	/*
697 	 * When ->invalidate_page runs, the linux pte has been zapped
698 	 * already but the page is still allocated until
699 	 * ->invalidate_page returns. So if we increase the sequence
700 	 * here the kvm page fault will notice if the spte can't be
701 	 * established because the page is going to be freed. If
702 	 * instead the kvm page fault establishes the spte before
703 	 * ->invalidate_page runs, kvm_unmap_hva will release it
704 	 * before returning.
705 	 *
706 	 * The sequence increase only need to be seen at spin_unlock
707 	 * time, and not at spin_lock time.
708 	 *
709 	 * Increasing the sequence after the spin_unlock would be
710 	 * unsafe because the kvm page fault could then establish the
711 	 * pte after kvm_unmap_hva returned, without noticing the page
712 	 * is going to be freed.
713 	 */
714 	spin_lock(&kvm->mmu_lock);
715 	kvm->mmu_notifier_seq++;
716 	need_tlb_flush = kvm_unmap_hva(kvm, address);
717 	spin_unlock(&kvm->mmu_lock);
718 
719 	/* we've to flush the tlb before the pages can be freed */
720 	if (need_tlb_flush)
721 		kvm_flush_remote_tlbs(kvm);
722 
723 }
724 
725 static void kvm_mmu_notifier_invalidate_range_start(struct mmu_notifier *mn,
726 						    struct mm_struct *mm,
727 						    unsigned long start,
728 						    unsigned long end)
729 {
730 	struct kvm *kvm = mmu_notifier_to_kvm(mn);
731 	int need_tlb_flush = 0;
732 
733 	spin_lock(&kvm->mmu_lock);
734 	/*
735 	 * The count increase must become visible at unlock time as no
736 	 * spte can be established without taking the mmu_lock and
737 	 * count is also read inside the mmu_lock critical section.
738 	 */
739 	kvm->mmu_notifier_count++;
740 	for (; start < end; start += PAGE_SIZE)
741 		need_tlb_flush |= kvm_unmap_hva(kvm, start);
742 	spin_unlock(&kvm->mmu_lock);
743 
744 	/* we've to flush the tlb before the pages can be freed */
745 	if (need_tlb_flush)
746 		kvm_flush_remote_tlbs(kvm);
747 }
748 
749 static void kvm_mmu_notifier_invalidate_range_end(struct mmu_notifier *mn,
750 						  struct mm_struct *mm,
751 						  unsigned long start,
752 						  unsigned long end)
753 {
754 	struct kvm *kvm = mmu_notifier_to_kvm(mn);
755 
756 	spin_lock(&kvm->mmu_lock);
757 	/*
758 	 * This sequence increase will notify the kvm page fault that
759 	 * the page that is going to be mapped in the spte could have
760 	 * been freed.
761 	 */
762 	kvm->mmu_notifier_seq++;
763 	/*
764 	 * The above sequence increase must be visible before the
765 	 * below count decrease but both values are read by the kvm
766 	 * page fault under mmu_lock spinlock so we don't need to add
767 	 * a smb_wmb() here in between the two.
768 	 */
769 	kvm->mmu_notifier_count--;
770 	spin_unlock(&kvm->mmu_lock);
771 
772 	BUG_ON(kvm->mmu_notifier_count < 0);
773 }
774 
775 static int kvm_mmu_notifier_clear_flush_young(struct mmu_notifier *mn,
776 					      struct mm_struct *mm,
777 					      unsigned long address)
778 {
779 	struct kvm *kvm = mmu_notifier_to_kvm(mn);
780 	int young;
781 
782 	spin_lock(&kvm->mmu_lock);
783 	young = kvm_age_hva(kvm, address);
784 	spin_unlock(&kvm->mmu_lock);
785 
786 	if (young)
787 		kvm_flush_remote_tlbs(kvm);
788 
789 	return young;
790 }
791 
792 static const struct mmu_notifier_ops kvm_mmu_notifier_ops = {
793 	.invalidate_page	= kvm_mmu_notifier_invalidate_page,
794 	.invalidate_range_start	= kvm_mmu_notifier_invalidate_range_start,
795 	.invalidate_range_end	= kvm_mmu_notifier_invalidate_range_end,
796 	.clear_flush_young	= kvm_mmu_notifier_clear_flush_young,
797 };
798 #endif /* CONFIG_MMU_NOTIFIER && KVM_ARCH_WANT_MMU_NOTIFIER */
799 
800 static struct kvm *kvm_create_vm(void)
801 {
802 	struct kvm *kvm = kvm_arch_create_vm();
803 #ifdef KVM_COALESCED_MMIO_PAGE_OFFSET
804 	struct page *page;
805 #endif
806 
807 	if (IS_ERR(kvm))
808 		goto out;
809 
810 #ifdef KVM_COALESCED_MMIO_PAGE_OFFSET
811 	page = alloc_page(GFP_KERNEL | __GFP_ZERO);
812 	if (!page) {
813 		kfree(kvm);
814 		return ERR_PTR(-ENOMEM);
815 	}
816 	kvm->coalesced_mmio_ring =
817 			(struct kvm_coalesced_mmio_ring *)page_address(page);
818 #endif
819 
820 #if defined(CONFIG_MMU_NOTIFIER) && defined(KVM_ARCH_WANT_MMU_NOTIFIER)
821 	{
822 		int err;
823 		kvm->mmu_notifier.ops = &kvm_mmu_notifier_ops;
824 		err = mmu_notifier_register(&kvm->mmu_notifier, current->mm);
825 		if (err) {
826 #ifdef KVM_COALESCED_MMIO_PAGE_OFFSET
827 			put_page(page);
828 #endif
829 			kfree(kvm);
830 			return ERR_PTR(err);
831 		}
832 	}
833 #endif
834 
835 	kvm->mm = current->mm;
836 	atomic_inc(&kvm->mm->mm_count);
837 	spin_lock_init(&kvm->mmu_lock);
838 	kvm_io_bus_init(&kvm->pio_bus);
839 	mutex_init(&kvm->lock);
840 	kvm_io_bus_init(&kvm->mmio_bus);
841 	init_rwsem(&kvm->slots_lock);
842 	atomic_set(&kvm->users_count, 1);
843 	spin_lock(&kvm_lock);
844 	list_add(&kvm->vm_list, &vm_list);
845 	spin_unlock(&kvm_lock);
846 #ifdef KVM_COALESCED_MMIO_PAGE_OFFSET
847 	kvm_coalesced_mmio_init(kvm);
848 #endif
849 out:
850 	return kvm;
851 }
852 
853 /*
854  * Free any memory in @free but not in @dont.
855  */
856 static void kvm_free_physmem_slot(struct kvm_memory_slot *free,
857 				  struct kvm_memory_slot *dont)
858 {
859 	if (!dont || free->rmap != dont->rmap)
860 		vfree(free->rmap);
861 
862 	if (!dont || free->dirty_bitmap != dont->dirty_bitmap)
863 		vfree(free->dirty_bitmap);
864 
865 	if (!dont || free->lpage_info != dont->lpage_info)
866 		vfree(free->lpage_info);
867 
868 	free->npages = 0;
869 	free->dirty_bitmap = NULL;
870 	free->rmap = NULL;
871 	free->lpage_info = NULL;
872 }
873 
874 void kvm_free_physmem(struct kvm *kvm)
875 {
876 	int i;
877 
878 	for (i = 0; i < kvm->nmemslots; ++i)
879 		kvm_free_physmem_slot(&kvm->memslots[i], NULL);
880 }
881 
882 static void kvm_destroy_vm(struct kvm *kvm)
883 {
884 	struct mm_struct *mm = kvm->mm;
885 
886 	spin_lock(&kvm_lock);
887 	list_del(&kvm->vm_list);
888 	spin_unlock(&kvm_lock);
889 	kvm_io_bus_destroy(&kvm->pio_bus);
890 	kvm_io_bus_destroy(&kvm->mmio_bus);
891 #ifdef KVM_COALESCED_MMIO_PAGE_OFFSET
892 	if (kvm->coalesced_mmio_ring != NULL)
893 		free_page((unsigned long)kvm->coalesced_mmio_ring);
894 #endif
895 #if defined(CONFIG_MMU_NOTIFIER) && defined(KVM_ARCH_WANT_MMU_NOTIFIER)
896 	mmu_notifier_unregister(&kvm->mmu_notifier, kvm->mm);
897 #endif
898 	kvm_arch_destroy_vm(kvm);
899 	mmdrop(mm);
900 }
901 
902 void kvm_get_kvm(struct kvm *kvm)
903 {
904 	atomic_inc(&kvm->users_count);
905 }
906 EXPORT_SYMBOL_GPL(kvm_get_kvm);
907 
908 void kvm_put_kvm(struct kvm *kvm)
909 {
910 	if (atomic_dec_and_test(&kvm->users_count))
911 		kvm_destroy_vm(kvm);
912 }
913 EXPORT_SYMBOL_GPL(kvm_put_kvm);
914 
915 
916 static int kvm_vm_release(struct inode *inode, struct file *filp)
917 {
918 	struct kvm *kvm = filp->private_data;
919 
920 	kvm_put_kvm(kvm);
921 	return 0;
922 }
923 
924 /*
925  * Allocate some memory and give it an address in the guest physical address
926  * space.
927  *
928  * Discontiguous memory is allowed, mostly for framebuffers.
929  *
930  * Must be called holding mmap_sem for write.
931  */
932 int __kvm_set_memory_region(struct kvm *kvm,
933 			    struct kvm_userspace_memory_region *mem,
934 			    int user_alloc)
935 {
936 	int r;
937 	gfn_t base_gfn;
938 	unsigned long npages;
939 	unsigned long i;
940 	struct kvm_memory_slot *memslot;
941 	struct kvm_memory_slot old, new;
942 
943 	r = -EINVAL;
944 	/* General sanity checks */
945 	if (mem->memory_size & (PAGE_SIZE - 1))
946 		goto out;
947 	if (mem->guest_phys_addr & (PAGE_SIZE - 1))
948 		goto out;
949 	if (user_alloc && (mem->userspace_addr & (PAGE_SIZE - 1)))
950 		goto out;
951 	if (mem->slot >= KVM_MEMORY_SLOTS + KVM_PRIVATE_MEM_SLOTS)
952 		goto out;
953 	if (mem->guest_phys_addr + mem->memory_size < mem->guest_phys_addr)
954 		goto out;
955 
956 	memslot = &kvm->memslots[mem->slot];
957 	base_gfn = mem->guest_phys_addr >> PAGE_SHIFT;
958 	npages = mem->memory_size >> PAGE_SHIFT;
959 
960 	if (!npages)
961 		mem->flags &= ~KVM_MEM_LOG_DIRTY_PAGES;
962 
963 	new = old = *memslot;
964 
965 	new.base_gfn = base_gfn;
966 	new.npages = npages;
967 	new.flags = mem->flags;
968 
969 	/* Disallow changing a memory slot's size. */
970 	r = -EINVAL;
971 	if (npages && old.npages && npages != old.npages)
972 		goto out_free;
973 
974 	/* Check for overlaps */
975 	r = -EEXIST;
976 	for (i = 0; i < KVM_MEMORY_SLOTS; ++i) {
977 		struct kvm_memory_slot *s = &kvm->memslots[i];
978 
979 		if (s == memslot)
980 			continue;
981 		if (!((base_gfn + npages <= s->base_gfn) ||
982 		      (base_gfn >= s->base_gfn + s->npages)))
983 			goto out_free;
984 	}
985 
986 	/* Free page dirty bitmap if unneeded */
987 	if (!(new.flags & KVM_MEM_LOG_DIRTY_PAGES))
988 		new.dirty_bitmap = NULL;
989 
990 	r = -ENOMEM;
991 
992 	/* Allocate if a slot is being created */
993 #ifndef CONFIG_S390
994 	if (npages && !new.rmap) {
995 		new.rmap = vmalloc(npages * sizeof(struct page *));
996 
997 		if (!new.rmap)
998 			goto out_free;
999 
1000 		memset(new.rmap, 0, npages * sizeof(*new.rmap));
1001 
1002 		new.user_alloc = user_alloc;
1003 		/*
1004 		 * hva_to_rmmap() serialzies with the mmu_lock and to be
1005 		 * safe it has to ignore memslots with !user_alloc &&
1006 		 * !userspace_addr.
1007 		 */
1008 		if (user_alloc)
1009 			new.userspace_addr = mem->userspace_addr;
1010 		else
1011 			new.userspace_addr = 0;
1012 	}
1013 	if (npages && !new.lpage_info) {
1014 		int largepages = npages / KVM_PAGES_PER_HPAGE;
1015 		if (npages % KVM_PAGES_PER_HPAGE)
1016 			largepages++;
1017 		if (base_gfn % KVM_PAGES_PER_HPAGE)
1018 			largepages++;
1019 
1020 		new.lpage_info = vmalloc(largepages * sizeof(*new.lpage_info));
1021 
1022 		if (!new.lpage_info)
1023 			goto out_free;
1024 
1025 		memset(new.lpage_info, 0, largepages * sizeof(*new.lpage_info));
1026 
1027 		if (base_gfn % KVM_PAGES_PER_HPAGE)
1028 			new.lpage_info[0].write_count = 1;
1029 		if ((base_gfn+npages) % KVM_PAGES_PER_HPAGE)
1030 			new.lpage_info[largepages-1].write_count = 1;
1031 	}
1032 
1033 	/* Allocate page dirty bitmap if needed */
1034 	if ((new.flags & KVM_MEM_LOG_DIRTY_PAGES) && !new.dirty_bitmap) {
1035 		unsigned dirty_bytes = ALIGN(npages, BITS_PER_LONG) / 8;
1036 
1037 		new.dirty_bitmap = vmalloc(dirty_bytes);
1038 		if (!new.dirty_bitmap)
1039 			goto out_free;
1040 		memset(new.dirty_bitmap, 0, dirty_bytes);
1041 	}
1042 #endif /* not defined CONFIG_S390 */
1043 
1044 	if (!npages)
1045 		kvm_arch_flush_shadow(kvm);
1046 
1047 	spin_lock(&kvm->mmu_lock);
1048 	if (mem->slot >= kvm->nmemslots)
1049 		kvm->nmemslots = mem->slot + 1;
1050 
1051 	*memslot = new;
1052 	spin_unlock(&kvm->mmu_lock);
1053 
1054 	r = kvm_arch_set_memory_region(kvm, mem, old, user_alloc);
1055 	if (r) {
1056 		spin_lock(&kvm->mmu_lock);
1057 		*memslot = old;
1058 		spin_unlock(&kvm->mmu_lock);
1059 		goto out_free;
1060 	}
1061 
1062 	kvm_free_physmem_slot(&old, npages ? &new : NULL);
1063 	/* Slot deletion case: we have to update the current slot */
1064 	if (!npages)
1065 		*memslot = old;
1066 #ifdef CONFIG_DMAR
1067 	/* map the pages in iommu page table */
1068 	r = kvm_iommu_map_pages(kvm, base_gfn, npages);
1069 	if (r)
1070 		goto out;
1071 #endif
1072 	return 0;
1073 
1074 out_free:
1075 	kvm_free_physmem_slot(&new, &old);
1076 out:
1077 	return r;
1078 
1079 }
1080 EXPORT_SYMBOL_GPL(__kvm_set_memory_region);
1081 
1082 int kvm_set_memory_region(struct kvm *kvm,
1083 			  struct kvm_userspace_memory_region *mem,
1084 			  int user_alloc)
1085 {
1086 	int r;
1087 
1088 	down_write(&kvm->slots_lock);
1089 	r = __kvm_set_memory_region(kvm, mem, user_alloc);
1090 	up_write(&kvm->slots_lock);
1091 	return r;
1092 }
1093 EXPORT_SYMBOL_GPL(kvm_set_memory_region);
1094 
1095 int kvm_vm_ioctl_set_memory_region(struct kvm *kvm,
1096 				   struct
1097 				   kvm_userspace_memory_region *mem,
1098 				   int user_alloc)
1099 {
1100 	if (mem->slot >= KVM_MEMORY_SLOTS)
1101 		return -EINVAL;
1102 	return kvm_set_memory_region(kvm, mem, user_alloc);
1103 }
1104 
1105 int kvm_get_dirty_log(struct kvm *kvm,
1106 			struct kvm_dirty_log *log, int *is_dirty)
1107 {
1108 	struct kvm_memory_slot *memslot;
1109 	int r, i;
1110 	int n;
1111 	unsigned long any = 0;
1112 
1113 	r = -EINVAL;
1114 	if (log->slot >= KVM_MEMORY_SLOTS)
1115 		goto out;
1116 
1117 	memslot = &kvm->memslots[log->slot];
1118 	r = -ENOENT;
1119 	if (!memslot->dirty_bitmap)
1120 		goto out;
1121 
1122 	n = ALIGN(memslot->npages, BITS_PER_LONG) / 8;
1123 
1124 	for (i = 0; !any && i < n/sizeof(long); ++i)
1125 		any = memslot->dirty_bitmap[i];
1126 
1127 	r = -EFAULT;
1128 	if (copy_to_user(log->dirty_bitmap, memslot->dirty_bitmap, n))
1129 		goto out;
1130 
1131 	if (any)
1132 		*is_dirty = 1;
1133 
1134 	r = 0;
1135 out:
1136 	return r;
1137 }
1138 
1139 int is_error_page(struct page *page)
1140 {
1141 	return page == bad_page;
1142 }
1143 EXPORT_SYMBOL_GPL(is_error_page);
1144 
1145 int is_error_pfn(pfn_t pfn)
1146 {
1147 	return pfn == bad_pfn;
1148 }
1149 EXPORT_SYMBOL_GPL(is_error_pfn);
1150 
1151 static inline unsigned long bad_hva(void)
1152 {
1153 	return PAGE_OFFSET;
1154 }
1155 
1156 int kvm_is_error_hva(unsigned long addr)
1157 {
1158 	return addr == bad_hva();
1159 }
1160 EXPORT_SYMBOL_GPL(kvm_is_error_hva);
1161 
1162 struct kvm_memory_slot *gfn_to_memslot_unaliased(struct kvm *kvm, gfn_t gfn)
1163 {
1164 	int i;
1165 
1166 	for (i = 0; i < kvm->nmemslots; ++i) {
1167 		struct kvm_memory_slot *memslot = &kvm->memslots[i];
1168 
1169 		if (gfn >= memslot->base_gfn
1170 		    && gfn < memslot->base_gfn + memslot->npages)
1171 			return memslot;
1172 	}
1173 	return NULL;
1174 }
1175 EXPORT_SYMBOL_GPL(gfn_to_memslot_unaliased);
1176 
1177 struct kvm_memory_slot *gfn_to_memslot(struct kvm *kvm, gfn_t gfn)
1178 {
1179 	gfn = unalias_gfn(kvm, gfn);
1180 	return gfn_to_memslot_unaliased(kvm, gfn);
1181 }
1182 
1183 int kvm_is_visible_gfn(struct kvm *kvm, gfn_t gfn)
1184 {
1185 	int i;
1186 
1187 	gfn = unalias_gfn(kvm, gfn);
1188 	for (i = 0; i < KVM_MEMORY_SLOTS; ++i) {
1189 		struct kvm_memory_slot *memslot = &kvm->memslots[i];
1190 
1191 		if (gfn >= memslot->base_gfn
1192 		    && gfn < memslot->base_gfn + memslot->npages)
1193 			return 1;
1194 	}
1195 	return 0;
1196 }
1197 EXPORT_SYMBOL_GPL(kvm_is_visible_gfn);
1198 
1199 unsigned long gfn_to_hva(struct kvm *kvm, gfn_t gfn)
1200 {
1201 	struct kvm_memory_slot *slot;
1202 
1203 	gfn = unalias_gfn(kvm, gfn);
1204 	slot = gfn_to_memslot_unaliased(kvm, gfn);
1205 	if (!slot)
1206 		return bad_hva();
1207 	return (slot->userspace_addr + (gfn - slot->base_gfn) * PAGE_SIZE);
1208 }
1209 EXPORT_SYMBOL_GPL(gfn_to_hva);
1210 
1211 pfn_t gfn_to_pfn(struct kvm *kvm, gfn_t gfn)
1212 {
1213 	struct page *page[1];
1214 	unsigned long addr;
1215 	int npages;
1216 	pfn_t pfn;
1217 
1218 	might_sleep();
1219 
1220 	addr = gfn_to_hva(kvm, gfn);
1221 	if (kvm_is_error_hva(addr)) {
1222 		get_page(bad_page);
1223 		return page_to_pfn(bad_page);
1224 	}
1225 
1226 	npages = get_user_pages_fast(addr, 1, 1, page);
1227 
1228 	if (unlikely(npages != 1)) {
1229 		struct vm_area_struct *vma;
1230 
1231 		down_read(&current->mm->mmap_sem);
1232 		vma = find_vma(current->mm, addr);
1233 
1234 		if (vma == NULL || addr < vma->vm_start ||
1235 		    !(vma->vm_flags & VM_PFNMAP)) {
1236 			up_read(&current->mm->mmap_sem);
1237 			get_page(bad_page);
1238 			return page_to_pfn(bad_page);
1239 		}
1240 
1241 		pfn = ((addr - vma->vm_start) >> PAGE_SHIFT) + vma->vm_pgoff;
1242 		up_read(&current->mm->mmap_sem);
1243 		BUG_ON(!kvm_is_mmio_pfn(pfn));
1244 	} else
1245 		pfn = page_to_pfn(page[0]);
1246 
1247 	return pfn;
1248 }
1249 
1250 EXPORT_SYMBOL_GPL(gfn_to_pfn);
1251 
1252 struct page *gfn_to_page(struct kvm *kvm, gfn_t gfn)
1253 {
1254 	pfn_t pfn;
1255 
1256 	pfn = gfn_to_pfn(kvm, gfn);
1257 	if (!kvm_is_mmio_pfn(pfn))
1258 		return pfn_to_page(pfn);
1259 
1260 	WARN_ON(kvm_is_mmio_pfn(pfn));
1261 
1262 	get_page(bad_page);
1263 	return bad_page;
1264 }
1265 
1266 EXPORT_SYMBOL_GPL(gfn_to_page);
1267 
1268 void kvm_release_page_clean(struct page *page)
1269 {
1270 	kvm_release_pfn_clean(page_to_pfn(page));
1271 }
1272 EXPORT_SYMBOL_GPL(kvm_release_page_clean);
1273 
1274 void kvm_release_pfn_clean(pfn_t pfn)
1275 {
1276 	if (!kvm_is_mmio_pfn(pfn))
1277 		put_page(pfn_to_page(pfn));
1278 }
1279 EXPORT_SYMBOL_GPL(kvm_release_pfn_clean);
1280 
1281 void kvm_release_page_dirty(struct page *page)
1282 {
1283 	kvm_release_pfn_dirty(page_to_pfn(page));
1284 }
1285 EXPORT_SYMBOL_GPL(kvm_release_page_dirty);
1286 
1287 void kvm_release_pfn_dirty(pfn_t pfn)
1288 {
1289 	kvm_set_pfn_dirty(pfn);
1290 	kvm_release_pfn_clean(pfn);
1291 }
1292 EXPORT_SYMBOL_GPL(kvm_release_pfn_dirty);
1293 
1294 void kvm_set_page_dirty(struct page *page)
1295 {
1296 	kvm_set_pfn_dirty(page_to_pfn(page));
1297 }
1298 EXPORT_SYMBOL_GPL(kvm_set_page_dirty);
1299 
1300 void kvm_set_pfn_dirty(pfn_t pfn)
1301 {
1302 	if (!kvm_is_mmio_pfn(pfn)) {
1303 		struct page *page = pfn_to_page(pfn);
1304 		if (!PageReserved(page))
1305 			SetPageDirty(page);
1306 	}
1307 }
1308 EXPORT_SYMBOL_GPL(kvm_set_pfn_dirty);
1309 
1310 void kvm_set_pfn_accessed(pfn_t pfn)
1311 {
1312 	if (!kvm_is_mmio_pfn(pfn))
1313 		mark_page_accessed(pfn_to_page(pfn));
1314 }
1315 EXPORT_SYMBOL_GPL(kvm_set_pfn_accessed);
1316 
1317 void kvm_get_pfn(pfn_t pfn)
1318 {
1319 	if (!kvm_is_mmio_pfn(pfn))
1320 		get_page(pfn_to_page(pfn));
1321 }
1322 EXPORT_SYMBOL_GPL(kvm_get_pfn);
1323 
1324 static int next_segment(unsigned long len, int offset)
1325 {
1326 	if (len > PAGE_SIZE - offset)
1327 		return PAGE_SIZE - offset;
1328 	else
1329 		return len;
1330 }
1331 
1332 int kvm_read_guest_page(struct kvm *kvm, gfn_t gfn, void *data, int offset,
1333 			int len)
1334 {
1335 	int r;
1336 	unsigned long addr;
1337 
1338 	addr = gfn_to_hva(kvm, gfn);
1339 	if (kvm_is_error_hva(addr))
1340 		return -EFAULT;
1341 	r = copy_from_user(data, (void __user *)addr + offset, len);
1342 	if (r)
1343 		return -EFAULT;
1344 	return 0;
1345 }
1346 EXPORT_SYMBOL_GPL(kvm_read_guest_page);
1347 
1348 int kvm_read_guest(struct kvm *kvm, gpa_t gpa, void *data, unsigned long len)
1349 {
1350 	gfn_t gfn = gpa >> PAGE_SHIFT;
1351 	int seg;
1352 	int offset = offset_in_page(gpa);
1353 	int ret;
1354 
1355 	while ((seg = next_segment(len, offset)) != 0) {
1356 		ret = kvm_read_guest_page(kvm, gfn, data, offset, seg);
1357 		if (ret < 0)
1358 			return ret;
1359 		offset = 0;
1360 		len -= seg;
1361 		data += seg;
1362 		++gfn;
1363 	}
1364 	return 0;
1365 }
1366 EXPORT_SYMBOL_GPL(kvm_read_guest);
1367 
1368 int kvm_read_guest_atomic(struct kvm *kvm, gpa_t gpa, void *data,
1369 			  unsigned long len)
1370 {
1371 	int r;
1372 	unsigned long addr;
1373 	gfn_t gfn = gpa >> PAGE_SHIFT;
1374 	int offset = offset_in_page(gpa);
1375 
1376 	addr = gfn_to_hva(kvm, gfn);
1377 	if (kvm_is_error_hva(addr))
1378 		return -EFAULT;
1379 	pagefault_disable();
1380 	r = __copy_from_user_inatomic(data, (void __user *)addr + offset, len);
1381 	pagefault_enable();
1382 	if (r)
1383 		return -EFAULT;
1384 	return 0;
1385 }
1386 EXPORT_SYMBOL(kvm_read_guest_atomic);
1387 
1388 int kvm_write_guest_page(struct kvm *kvm, gfn_t gfn, const void *data,
1389 			 int offset, int len)
1390 {
1391 	int r;
1392 	unsigned long addr;
1393 
1394 	addr = gfn_to_hva(kvm, gfn);
1395 	if (kvm_is_error_hva(addr))
1396 		return -EFAULT;
1397 	r = copy_to_user((void __user *)addr + offset, data, len);
1398 	if (r)
1399 		return -EFAULT;
1400 	mark_page_dirty(kvm, gfn);
1401 	return 0;
1402 }
1403 EXPORT_SYMBOL_GPL(kvm_write_guest_page);
1404 
1405 int kvm_write_guest(struct kvm *kvm, gpa_t gpa, const void *data,
1406 		    unsigned long len)
1407 {
1408 	gfn_t gfn = gpa >> PAGE_SHIFT;
1409 	int seg;
1410 	int offset = offset_in_page(gpa);
1411 	int ret;
1412 
1413 	while ((seg = next_segment(len, offset)) != 0) {
1414 		ret = kvm_write_guest_page(kvm, gfn, data, offset, seg);
1415 		if (ret < 0)
1416 			return ret;
1417 		offset = 0;
1418 		len -= seg;
1419 		data += seg;
1420 		++gfn;
1421 	}
1422 	return 0;
1423 }
1424 
1425 int kvm_clear_guest_page(struct kvm *kvm, gfn_t gfn, int offset, int len)
1426 {
1427 	return kvm_write_guest_page(kvm, gfn, empty_zero_page, offset, len);
1428 }
1429 EXPORT_SYMBOL_GPL(kvm_clear_guest_page);
1430 
1431 int kvm_clear_guest(struct kvm *kvm, gpa_t gpa, unsigned long len)
1432 {
1433 	gfn_t gfn = gpa >> PAGE_SHIFT;
1434 	int seg;
1435 	int offset = offset_in_page(gpa);
1436 	int ret;
1437 
1438         while ((seg = next_segment(len, offset)) != 0) {
1439 		ret = kvm_clear_guest_page(kvm, gfn, offset, seg);
1440 		if (ret < 0)
1441 			return ret;
1442 		offset = 0;
1443 		len -= seg;
1444 		++gfn;
1445 	}
1446 	return 0;
1447 }
1448 EXPORT_SYMBOL_GPL(kvm_clear_guest);
1449 
1450 void mark_page_dirty(struct kvm *kvm, gfn_t gfn)
1451 {
1452 	struct kvm_memory_slot *memslot;
1453 
1454 	gfn = unalias_gfn(kvm, gfn);
1455 	memslot = gfn_to_memslot_unaliased(kvm, gfn);
1456 	if (memslot && memslot->dirty_bitmap) {
1457 		unsigned long rel_gfn = gfn - memslot->base_gfn;
1458 
1459 		/* avoid RMW */
1460 		if (!test_bit(rel_gfn, memslot->dirty_bitmap))
1461 			set_bit(rel_gfn, memslot->dirty_bitmap);
1462 	}
1463 }
1464 
1465 /*
1466  * The vCPU has executed a HLT instruction with in-kernel mode enabled.
1467  */
1468 void kvm_vcpu_block(struct kvm_vcpu *vcpu)
1469 {
1470 	DEFINE_WAIT(wait);
1471 
1472 	for (;;) {
1473 		prepare_to_wait(&vcpu->wq, &wait, TASK_INTERRUPTIBLE);
1474 
1475 		if (kvm_cpu_has_interrupt(vcpu) ||
1476 		    kvm_cpu_has_pending_timer(vcpu) ||
1477 		    kvm_arch_vcpu_runnable(vcpu)) {
1478 			set_bit(KVM_REQ_UNHALT, &vcpu->requests);
1479 			break;
1480 		}
1481 		if (signal_pending(current))
1482 			break;
1483 
1484 		vcpu_put(vcpu);
1485 		schedule();
1486 		vcpu_load(vcpu);
1487 	}
1488 
1489 	finish_wait(&vcpu->wq, &wait);
1490 }
1491 
1492 void kvm_resched(struct kvm_vcpu *vcpu)
1493 {
1494 	if (!need_resched())
1495 		return;
1496 	cond_resched();
1497 }
1498 EXPORT_SYMBOL_GPL(kvm_resched);
1499 
1500 static int kvm_vcpu_fault(struct vm_area_struct *vma, struct vm_fault *vmf)
1501 {
1502 	struct kvm_vcpu *vcpu = vma->vm_file->private_data;
1503 	struct page *page;
1504 
1505 	if (vmf->pgoff == 0)
1506 		page = virt_to_page(vcpu->run);
1507 #ifdef CONFIG_X86
1508 	else if (vmf->pgoff == KVM_PIO_PAGE_OFFSET)
1509 		page = virt_to_page(vcpu->arch.pio_data);
1510 #endif
1511 #ifdef KVM_COALESCED_MMIO_PAGE_OFFSET
1512 	else if (vmf->pgoff == KVM_COALESCED_MMIO_PAGE_OFFSET)
1513 		page = virt_to_page(vcpu->kvm->coalesced_mmio_ring);
1514 #endif
1515 	else
1516 		return VM_FAULT_SIGBUS;
1517 	get_page(page);
1518 	vmf->page = page;
1519 	return 0;
1520 }
1521 
1522 static struct vm_operations_struct kvm_vcpu_vm_ops = {
1523 	.fault = kvm_vcpu_fault,
1524 };
1525 
1526 static int kvm_vcpu_mmap(struct file *file, struct vm_area_struct *vma)
1527 {
1528 	vma->vm_ops = &kvm_vcpu_vm_ops;
1529 	return 0;
1530 }
1531 
1532 static int kvm_vcpu_release(struct inode *inode, struct file *filp)
1533 {
1534 	struct kvm_vcpu *vcpu = filp->private_data;
1535 
1536 	kvm_put_kvm(vcpu->kvm);
1537 	return 0;
1538 }
1539 
1540 static struct file_operations kvm_vcpu_fops = {
1541 	.release        = kvm_vcpu_release,
1542 	.unlocked_ioctl = kvm_vcpu_ioctl,
1543 	.compat_ioctl   = kvm_vcpu_ioctl,
1544 	.mmap           = kvm_vcpu_mmap,
1545 };
1546 
1547 /*
1548  * Allocates an inode for the vcpu.
1549  */
1550 static int create_vcpu_fd(struct kvm_vcpu *vcpu)
1551 {
1552 	int fd = anon_inode_getfd("kvm-vcpu", &kvm_vcpu_fops, vcpu, 0);
1553 	if (fd < 0)
1554 		kvm_put_kvm(vcpu->kvm);
1555 	return fd;
1556 }
1557 
1558 /*
1559  * Creates some virtual cpus.  Good luck creating more than one.
1560  */
1561 static int kvm_vm_ioctl_create_vcpu(struct kvm *kvm, int n)
1562 {
1563 	int r;
1564 	struct kvm_vcpu *vcpu;
1565 
1566 	if (!valid_vcpu(n))
1567 		return -EINVAL;
1568 
1569 	vcpu = kvm_arch_vcpu_create(kvm, n);
1570 	if (IS_ERR(vcpu))
1571 		return PTR_ERR(vcpu);
1572 
1573 	preempt_notifier_init(&vcpu->preempt_notifier, &kvm_preempt_ops);
1574 
1575 	r = kvm_arch_vcpu_setup(vcpu);
1576 	if (r)
1577 		return r;
1578 
1579 	mutex_lock(&kvm->lock);
1580 	if (kvm->vcpus[n]) {
1581 		r = -EEXIST;
1582 		goto vcpu_destroy;
1583 	}
1584 	kvm->vcpus[n] = vcpu;
1585 	mutex_unlock(&kvm->lock);
1586 
1587 	/* Now it's all set up, let userspace reach it */
1588 	kvm_get_kvm(kvm);
1589 	r = create_vcpu_fd(vcpu);
1590 	if (r < 0)
1591 		goto unlink;
1592 	return r;
1593 
1594 unlink:
1595 	mutex_lock(&kvm->lock);
1596 	kvm->vcpus[n] = NULL;
1597 vcpu_destroy:
1598 	mutex_unlock(&kvm->lock);
1599 	kvm_arch_vcpu_destroy(vcpu);
1600 	return r;
1601 }
1602 
1603 static int kvm_vcpu_ioctl_set_sigmask(struct kvm_vcpu *vcpu, sigset_t *sigset)
1604 {
1605 	if (sigset) {
1606 		sigdelsetmask(sigset, sigmask(SIGKILL)|sigmask(SIGSTOP));
1607 		vcpu->sigset_active = 1;
1608 		vcpu->sigset = *sigset;
1609 	} else
1610 		vcpu->sigset_active = 0;
1611 	return 0;
1612 }
1613 
1614 static long kvm_vcpu_ioctl(struct file *filp,
1615 			   unsigned int ioctl, unsigned long arg)
1616 {
1617 	struct kvm_vcpu *vcpu = filp->private_data;
1618 	void __user *argp = (void __user *)arg;
1619 	int r;
1620 	struct kvm_fpu *fpu = NULL;
1621 	struct kvm_sregs *kvm_sregs = NULL;
1622 
1623 	if (vcpu->kvm->mm != current->mm)
1624 		return -EIO;
1625 	switch (ioctl) {
1626 	case KVM_RUN:
1627 		r = -EINVAL;
1628 		if (arg)
1629 			goto out;
1630 		r = kvm_arch_vcpu_ioctl_run(vcpu, vcpu->run);
1631 		break;
1632 	case KVM_GET_REGS: {
1633 		struct kvm_regs *kvm_regs;
1634 
1635 		r = -ENOMEM;
1636 		kvm_regs = kzalloc(sizeof(struct kvm_regs), GFP_KERNEL);
1637 		if (!kvm_regs)
1638 			goto out;
1639 		r = kvm_arch_vcpu_ioctl_get_regs(vcpu, kvm_regs);
1640 		if (r)
1641 			goto out_free1;
1642 		r = -EFAULT;
1643 		if (copy_to_user(argp, kvm_regs, sizeof(struct kvm_regs)))
1644 			goto out_free1;
1645 		r = 0;
1646 out_free1:
1647 		kfree(kvm_regs);
1648 		break;
1649 	}
1650 	case KVM_SET_REGS: {
1651 		struct kvm_regs *kvm_regs;
1652 
1653 		r = -ENOMEM;
1654 		kvm_regs = kzalloc(sizeof(struct kvm_regs), GFP_KERNEL);
1655 		if (!kvm_regs)
1656 			goto out;
1657 		r = -EFAULT;
1658 		if (copy_from_user(kvm_regs, argp, sizeof(struct kvm_regs)))
1659 			goto out_free2;
1660 		r = kvm_arch_vcpu_ioctl_set_regs(vcpu, kvm_regs);
1661 		if (r)
1662 			goto out_free2;
1663 		r = 0;
1664 out_free2:
1665 		kfree(kvm_regs);
1666 		break;
1667 	}
1668 	case KVM_GET_SREGS: {
1669 		kvm_sregs = kzalloc(sizeof(struct kvm_sregs), GFP_KERNEL);
1670 		r = -ENOMEM;
1671 		if (!kvm_sregs)
1672 			goto out;
1673 		r = kvm_arch_vcpu_ioctl_get_sregs(vcpu, kvm_sregs);
1674 		if (r)
1675 			goto out;
1676 		r = -EFAULT;
1677 		if (copy_to_user(argp, kvm_sregs, sizeof(struct kvm_sregs)))
1678 			goto out;
1679 		r = 0;
1680 		break;
1681 	}
1682 	case KVM_SET_SREGS: {
1683 		kvm_sregs = kmalloc(sizeof(struct kvm_sregs), GFP_KERNEL);
1684 		r = -ENOMEM;
1685 		if (!kvm_sregs)
1686 			goto out;
1687 		r = -EFAULT;
1688 		if (copy_from_user(kvm_sregs, argp, sizeof(struct kvm_sregs)))
1689 			goto out;
1690 		r = kvm_arch_vcpu_ioctl_set_sregs(vcpu, kvm_sregs);
1691 		if (r)
1692 			goto out;
1693 		r = 0;
1694 		break;
1695 	}
1696 	case KVM_GET_MP_STATE: {
1697 		struct kvm_mp_state mp_state;
1698 
1699 		r = kvm_arch_vcpu_ioctl_get_mpstate(vcpu, &mp_state);
1700 		if (r)
1701 			goto out;
1702 		r = -EFAULT;
1703 		if (copy_to_user(argp, &mp_state, sizeof mp_state))
1704 			goto out;
1705 		r = 0;
1706 		break;
1707 	}
1708 	case KVM_SET_MP_STATE: {
1709 		struct kvm_mp_state mp_state;
1710 
1711 		r = -EFAULT;
1712 		if (copy_from_user(&mp_state, argp, sizeof mp_state))
1713 			goto out;
1714 		r = kvm_arch_vcpu_ioctl_set_mpstate(vcpu, &mp_state);
1715 		if (r)
1716 			goto out;
1717 		r = 0;
1718 		break;
1719 	}
1720 	case KVM_TRANSLATE: {
1721 		struct kvm_translation tr;
1722 
1723 		r = -EFAULT;
1724 		if (copy_from_user(&tr, argp, sizeof tr))
1725 			goto out;
1726 		r = kvm_arch_vcpu_ioctl_translate(vcpu, &tr);
1727 		if (r)
1728 			goto out;
1729 		r = -EFAULT;
1730 		if (copy_to_user(argp, &tr, sizeof tr))
1731 			goto out;
1732 		r = 0;
1733 		break;
1734 	}
1735 	case KVM_DEBUG_GUEST: {
1736 		struct kvm_debug_guest dbg;
1737 
1738 		r = -EFAULT;
1739 		if (copy_from_user(&dbg, argp, sizeof dbg))
1740 			goto out;
1741 		r = kvm_arch_vcpu_ioctl_debug_guest(vcpu, &dbg);
1742 		if (r)
1743 			goto out;
1744 		r = 0;
1745 		break;
1746 	}
1747 	case KVM_SET_SIGNAL_MASK: {
1748 		struct kvm_signal_mask __user *sigmask_arg = argp;
1749 		struct kvm_signal_mask kvm_sigmask;
1750 		sigset_t sigset, *p;
1751 
1752 		p = NULL;
1753 		if (argp) {
1754 			r = -EFAULT;
1755 			if (copy_from_user(&kvm_sigmask, argp,
1756 					   sizeof kvm_sigmask))
1757 				goto out;
1758 			r = -EINVAL;
1759 			if (kvm_sigmask.len != sizeof sigset)
1760 				goto out;
1761 			r = -EFAULT;
1762 			if (copy_from_user(&sigset, sigmask_arg->sigset,
1763 					   sizeof sigset))
1764 				goto out;
1765 			p = &sigset;
1766 		}
1767 		r = kvm_vcpu_ioctl_set_sigmask(vcpu, &sigset);
1768 		break;
1769 	}
1770 	case KVM_GET_FPU: {
1771 		fpu = kzalloc(sizeof(struct kvm_fpu), GFP_KERNEL);
1772 		r = -ENOMEM;
1773 		if (!fpu)
1774 			goto out;
1775 		r = kvm_arch_vcpu_ioctl_get_fpu(vcpu, fpu);
1776 		if (r)
1777 			goto out;
1778 		r = -EFAULT;
1779 		if (copy_to_user(argp, fpu, sizeof(struct kvm_fpu)))
1780 			goto out;
1781 		r = 0;
1782 		break;
1783 	}
1784 	case KVM_SET_FPU: {
1785 		fpu = kmalloc(sizeof(struct kvm_fpu), GFP_KERNEL);
1786 		r = -ENOMEM;
1787 		if (!fpu)
1788 			goto out;
1789 		r = -EFAULT;
1790 		if (copy_from_user(fpu, argp, sizeof(struct kvm_fpu)))
1791 			goto out;
1792 		r = kvm_arch_vcpu_ioctl_set_fpu(vcpu, fpu);
1793 		if (r)
1794 			goto out;
1795 		r = 0;
1796 		break;
1797 	}
1798 	default:
1799 		r = kvm_arch_vcpu_ioctl(filp, ioctl, arg);
1800 	}
1801 out:
1802 	kfree(fpu);
1803 	kfree(kvm_sregs);
1804 	return r;
1805 }
1806 
1807 static long kvm_vm_ioctl(struct file *filp,
1808 			   unsigned int ioctl, unsigned long arg)
1809 {
1810 	struct kvm *kvm = filp->private_data;
1811 	void __user *argp = (void __user *)arg;
1812 	int r;
1813 
1814 	if (kvm->mm != current->mm)
1815 		return -EIO;
1816 	switch (ioctl) {
1817 	case KVM_CREATE_VCPU:
1818 		r = kvm_vm_ioctl_create_vcpu(kvm, arg);
1819 		if (r < 0)
1820 			goto out;
1821 		break;
1822 	case KVM_SET_USER_MEMORY_REGION: {
1823 		struct kvm_userspace_memory_region kvm_userspace_mem;
1824 
1825 		r = -EFAULT;
1826 		if (copy_from_user(&kvm_userspace_mem, argp,
1827 						sizeof kvm_userspace_mem))
1828 			goto out;
1829 
1830 		r = kvm_vm_ioctl_set_memory_region(kvm, &kvm_userspace_mem, 1);
1831 		if (r)
1832 			goto out;
1833 		break;
1834 	}
1835 	case KVM_GET_DIRTY_LOG: {
1836 		struct kvm_dirty_log log;
1837 
1838 		r = -EFAULT;
1839 		if (copy_from_user(&log, argp, sizeof log))
1840 			goto out;
1841 		r = kvm_vm_ioctl_get_dirty_log(kvm, &log);
1842 		if (r)
1843 			goto out;
1844 		break;
1845 	}
1846 #ifdef KVM_COALESCED_MMIO_PAGE_OFFSET
1847 	case KVM_REGISTER_COALESCED_MMIO: {
1848 		struct kvm_coalesced_mmio_zone zone;
1849 		r = -EFAULT;
1850 		if (copy_from_user(&zone, argp, sizeof zone))
1851 			goto out;
1852 		r = -ENXIO;
1853 		r = kvm_vm_ioctl_register_coalesced_mmio(kvm, &zone);
1854 		if (r)
1855 			goto out;
1856 		r = 0;
1857 		break;
1858 	}
1859 	case KVM_UNREGISTER_COALESCED_MMIO: {
1860 		struct kvm_coalesced_mmio_zone zone;
1861 		r = -EFAULT;
1862 		if (copy_from_user(&zone, argp, sizeof zone))
1863 			goto out;
1864 		r = -ENXIO;
1865 		r = kvm_vm_ioctl_unregister_coalesced_mmio(kvm, &zone);
1866 		if (r)
1867 			goto out;
1868 		r = 0;
1869 		break;
1870 	}
1871 #endif
1872 #ifdef KVM_CAP_DEVICE_ASSIGNMENT
1873 	case KVM_ASSIGN_PCI_DEVICE: {
1874 		struct kvm_assigned_pci_dev assigned_dev;
1875 
1876 		r = -EFAULT;
1877 		if (copy_from_user(&assigned_dev, argp, sizeof assigned_dev))
1878 			goto out;
1879 		r = kvm_vm_ioctl_assign_device(kvm, &assigned_dev);
1880 		if (r)
1881 			goto out;
1882 		break;
1883 	}
1884 	case KVM_ASSIGN_IRQ: {
1885 		struct kvm_assigned_irq assigned_irq;
1886 
1887 		r = -EFAULT;
1888 		if (copy_from_user(&assigned_irq, argp, sizeof assigned_irq))
1889 			goto out;
1890 		r = kvm_vm_ioctl_assign_irq(kvm, &assigned_irq);
1891 		if (r)
1892 			goto out;
1893 		break;
1894 	}
1895 #endif
1896 #ifdef KVM_CAP_DEVICE_DEASSIGNMENT
1897 	case KVM_DEASSIGN_PCI_DEVICE: {
1898 		struct kvm_assigned_pci_dev assigned_dev;
1899 
1900 		r = -EFAULT;
1901 		if (copy_from_user(&assigned_dev, argp, sizeof assigned_dev))
1902 			goto out;
1903 		r = kvm_vm_ioctl_deassign_device(kvm, &assigned_dev);
1904 		if (r)
1905 			goto out;
1906 		break;
1907 	}
1908 #endif
1909 	default:
1910 		r = kvm_arch_vm_ioctl(filp, ioctl, arg);
1911 	}
1912 out:
1913 	return r;
1914 }
1915 
1916 static int kvm_vm_fault(struct vm_area_struct *vma, struct vm_fault *vmf)
1917 {
1918 	struct page *page[1];
1919 	unsigned long addr;
1920 	int npages;
1921 	gfn_t gfn = vmf->pgoff;
1922 	struct kvm *kvm = vma->vm_file->private_data;
1923 
1924 	addr = gfn_to_hva(kvm, gfn);
1925 	if (kvm_is_error_hva(addr))
1926 		return VM_FAULT_SIGBUS;
1927 
1928 	npages = get_user_pages(current, current->mm, addr, 1, 1, 0, page,
1929 				NULL);
1930 	if (unlikely(npages != 1))
1931 		return VM_FAULT_SIGBUS;
1932 
1933 	vmf->page = page[0];
1934 	return 0;
1935 }
1936 
1937 static struct vm_operations_struct kvm_vm_vm_ops = {
1938 	.fault = kvm_vm_fault,
1939 };
1940 
1941 static int kvm_vm_mmap(struct file *file, struct vm_area_struct *vma)
1942 {
1943 	vma->vm_ops = &kvm_vm_vm_ops;
1944 	return 0;
1945 }
1946 
1947 static struct file_operations kvm_vm_fops = {
1948 	.release        = kvm_vm_release,
1949 	.unlocked_ioctl = kvm_vm_ioctl,
1950 	.compat_ioctl   = kvm_vm_ioctl,
1951 	.mmap           = kvm_vm_mmap,
1952 };
1953 
1954 static int kvm_dev_ioctl_create_vm(void)
1955 {
1956 	int fd;
1957 	struct kvm *kvm;
1958 
1959 	kvm = kvm_create_vm();
1960 	if (IS_ERR(kvm))
1961 		return PTR_ERR(kvm);
1962 	fd = anon_inode_getfd("kvm-vm", &kvm_vm_fops, kvm, 0);
1963 	if (fd < 0)
1964 		kvm_put_kvm(kvm);
1965 
1966 	return fd;
1967 }
1968 
1969 static long kvm_dev_ioctl_check_extension_generic(long arg)
1970 {
1971 	switch (arg) {
1972 	case KVM_CAP_USER_MEMORY:
1973 	case KVM_CAP_DESTROY_MEMORY_REGION_WORKS:
1974 		return 1;
1975 	default:
1976 		break;
1977 	}
1978 	return kvm_dev_ioctl_check_extension(arg);
1979 }
1980 
1981 static long kvm_dev_ioctl(struct file *filp,
1982 			  unsigned int ioctl, unsigned long arg)
1983 {
1984 	long r = -EINVAL;
1985 
1986 	switch (ioctl) {
1987 	case KVM_GET_API_VERSION:
1988 		r = -EINVAL;
1989 		if (arg)
1990 			goto out;
1991 		r = KVM_API_VERSION;
1992 		break;
1993 	case KVM_CREATE_VM:
1994 		r = -EINVAL;
1995 		if (arg)
1996 			goto out;
1997 		r = kvm_dev_ioctl_create_vm();
1998 		break;
1999 	case KVM_CHECK_EXTENSION:
2000 		r = kvm_dev_ioctl_check_extension_generic(arg);
2001 		break;
2002 	case KVM_GET_VCPU_MMAP_SIZE:
2003 		r = -EINVAL;
2004 		if (arg)
2005 			goto out;
2006 		r = PAGE_SIZE;     /* struct kvm_run */
2007 #ifdef CONFIG_X86
2008 		r += PAGE_SIZE;    /* pio data page */
2009 #endif
2010 #ifdef KVM_COALESCED_MMIO_PAGE_OFFSET
2011 		r += PAGE_SIZE;    /* coalesced mmio ring page */
2012 #endif
2013 		break;
2014 	case KVM_TRACE_ENABLE:
2015 	case KVM_TRACE_PAUSE:
2016 	case KVM_TRACE_DISABLE:
2017 		r = kvm_trace_ioctl(ioctl, arg);
2018 		break;
2019 	default:
2020 		return kvm_arch_dev_ioctl(filp, ioctl, arg);
2021 	}
2022 out:
2023 	return r;
2024 }
2025 
2026 static struct file_operations kvm_chardev_ops = {
2027 	.unlocked_ioctl = kvm_dev_ioctl,
2028 	.compat_ioctl   = kvm_dev_ioctl,
2029 };
2030 
2031 static struct miscdevice kvm_dev = {
2032 	KVM_MINOR,
2033 	"kvm",
2034 	&kvm_chardev_ops,
2035 };
2036 
2037 static void hardware_enable(void *junk)
2038 {
2039 	int cpu = raw_smp_processor_id();
2040 
2041 	if (cpumask_test_cpu(cpu, cpus_hardware_enabled))
2042 		return;
2043 	cpumask_set_cpu(cpu, cpus_hardware_enabled);
2044 	kvm_arch_hardware_enable(NULL);
2045 }
2046 
2047 static void hardware_disable(void *junk)
2048 {
2049 	int cpu = raw_smp_processor_id();
2050 
2051 	if (!cpumask_test_cpu(cpu, cpus_hardware_enabled))
2052 		return;
2053 	cpumask_clear_cpu(cpu, cpus_hardware_enabled);
2054 	kvm_arch_hardware_disable(NULL);
2055 }
2056 
2057 static int kvm_cpu_hotplug(struct notifier_block *notifier, unsigned long val,
2058 			   void *v)
2059 {
2060 	int cpu = (long)v;
2061 
2062 	val &= ~CPU_TASKS_FROZEN;
2063 	switch (val) {
2064 	case CPU_DYING:
2065 		printk(KERN_INFO "kvm: disabling virtualization on CPU%d\n",
2066 		       cpu);
2067 		hardware_disable(NULL);
2068 		break;
2069 	case CPU_UP_CANCELED:
2070 		printk(KERN_INFO "kvm: disabling virtualization on CPU%d\n",
2071 		       cpu);
2072 		smp_call_function_single(cpu, hardware_disable, NULL, 1);
2073 		break;
2074 	case CPU_ONLINE:
2075 		printk(KERN_INFO "kvm: enabling virtualization on CPU%d\n",
2076 		       cpu);
2077 		smp_call_function_single(cpu, hardware_enable, NULL, 1);
2078 		break;
2079 	}
2080 	return NOTIFY_OK;
2081 }
2082 
2083 
2084 asmlinkage void kvm_handle_fault_on_reboot(void)
2085 {
2086 	if (kvm_rebooting)
2087 		/* spin while reset goes on */
2088 		while (true)
2089 			;
2090 	/* Fault while not rebooting.  We want the trace. */
2091 	BUG();
2092 }
2093 EXPORT_SYMBOL_GPL(kvm_handle_fault_on_reboot);
2094 
2095 static int kvm_reboot(struct notifier_block *notifier, unsigned long val,
2096 		      void *v)
2097 {
2098 	if (val == SYS_RESTART) {
2099 		/*
2100 		 * Some (well, at least mine) BIOSes hang on reboot if
2101 		 * in vmx root mode.
2102 		 */
2103 		printk(KERN_INFO "kvm: exiting hardware virtualization\n");
2104 		kvm_rebooting = true;
2105 		on_each_cpu(hardware_disable, NULL, 1);
2106 	}
2107 	return NOTIFY_OK;
2108 }
2109 
2110 static struct notifier_block kvm_reboot_notifier = {
2111 	.notifier_call = kvm_reboot,
2112 	.priority = 0,
2113 };
2114 
2115 void kvm_io_bus_init(struct kvm_io_bus *bus)
2116 {
2117 	memset(bus, 0, sizeof(*bus));
2118 }
2119 
2120 void kvm_io_bus_destroy(struct kvm_io_bus *bus)
2121 {
2122 	int i;
2123 
2124 	for (i = 0; i < bus->dev_count; i++) {
2125 		struct kvm_io_device *pos = bus->devs[i];
2126 
2127 		kvm_iodevice_destructor(pos);
2128 	}
2129 }
2130 
2131 struct kvm_io_device *kvm_io_bus_find_dev(struct kvm_io_bus *bus,
2132 					  gpa_t addr, int len, int is_write)
2133 {
2134 	int i;
2135 
2136 	for (i = 0; i < bus->dev_count; i++) {
2137 		struct kvm_io_device *pos = bus->devs[i];
2138 
2139 		if (pos->in_range(pos, addr, len, is_write))
2140 			return pos;
2141 	}
2142 
2143 	return NULL;
2144 }
2145 
2146 void kvm_io_bus_register_dev(struct kvm_io_bus *bus, struct kvm_io_device *dev)
2147 {
2148 	BUG_ON(bus->dev_count > (NR_IOBUS_DEVS-1));
2149 
2150 	bus->devs[bus->dev_count++] = dev;
2151 }
2152 
2153 static struct notifier_block kvm_cpu_notifier = {
2154 	.notifier_call = kvm_cpu_hotplug,
2155 	.priority = 20, /* must be > scheduler priority */
2156 };
2157 
2158 static int vm_stat_get(void *_offset, u64 *val)
2159 {
2160 	unsigned offset = (long)_offset;
2161 	struct kvm *kvm;
2162 
2163 	*val = 0;
2164 	spin_lock(&kvm_lock);
2165 	list_for_each_entry(kvm, &vm_list, vm_list)
2166 		*val += *(u32 *)((void *)kvm + offset);
2167 	spin_unlock(&kvm_lock);
2168 	return 0;
2169 }
2170 
2171 DEFINE_SIMPLE_ATTRIBUTE(vm_stat_fops, vm_stat_get, NULL, "%llu\n");
2172 
2173 static int vcpu_stat_get(void *_offset, u64 *val)
2174 {
2175 	unsigned offset = (long)_offset;
2176 	struct kvm *kvm;
2177 	struct kvm_vcpu *vcpu;
2178 	int i;
2179 
2180 	*val = 0;
2181 	spin_lock(&kvm_lock);
2182 	list_for_each_entry(kvm, &vm_list, vm_list)
2183 		for (i = 0; i < KVM_MAX_VCPUS; ++i) {
2184 			vcpu = kvm->vcpus[i];
2185 			if (vcpu)
2186 				*val += *(u32 *)((void *)vcpu + offset);
2187 		}
2188 	spin_unlock(&kvm_lock);
2189 	return 0;
2190 }
2191 
2192 DEFINE_SIMPLE_ATTRIBUTE(vcpu_stat_fops, vcpu_stat_get, NULL, "%llu\n");
2193 
2194 static struct file_operations *stat_fops[] = {
2195 	[KVM_STAT_VCPU] = &vcpu_stat_fops,
2196 	[KVM_STAT_VM]   = &vm_stat_fops,
2197 };
2198 
2199 static void kvm_init_debug(void)
2200 {
2201 	struct kvm_stats_debugfs_item *p;
2202 
2203 	kvm_debugfs_dir = debugfs_create_dir("kvm", NULL);
2204 	for (p = debugfs_entries; p->name; ++p)
2205 		p->dentry = debugfs_create_file(p->name, 0444, kvm_debugfs_dir,
2206 						(void *)(long)p->offset,
2207 						stat_fops[p->kind]);
2208 }
2209 
2210 static void kvm_exit_debug(void)
2211 {
2212 	struct kvm_stats_debugfs_item *p;
2213 
2214 	for (p = debugfs_entries; p->name; ++p)
2215 		debugfs_remove(p->dentry);
2216 	debugfs_remove(kvm_debugfs_dir);
2217 }
2218 
2219 static int kvm_suspend(struct sys_device *dev, pm_message_t state)
2220 {
2221 	hardware_disable(NULL);
2222 	return 0;
2223 }
2224 
2225 static int kvm_resume(struct sys_device *dev)
2226 {
2227 	hardware_enable(NULL);
2228 	return 0;
2229 }
2230 
2231 static struct sysdev_class kvm_sysdev_class = {
2232 	.name = "kvm",
2233 	.suspend = kvm_suspend,
2234 	.resume = kvm_resume,
2235 };
2236 
2237 static struct sys_device kvm_sysdev = {
2238 	.id = 0,
2239 	.cls = &kvm_sysdev_class,
2240 };
2241 
2242 struct page *bad_page;
2243 pfn_t bad_pfn;
2244 
2245 static inline
2246 struct kvm_vcpu *preempt_notifier_to_vcpu(struct preempt_notifier *pn)
2247 {
2248 	return container_of(pn, struct kvm_vcpu, preempt_notifier);
2249 }
2250 
2251 static void kvm_sched_in(struct preempt_notifier *pn, int cpu)
2252 {
2253 	struct kvm_vcpu *vcpu = preempt_notifier_to_vcpu(pn);
2254 
2255 	kvm_arch_vcpu_load(vcpu, cpu);
2256 }
2257 
2258 static void kvm_sched_out(struct preempt_notifier *pn,
2259 			  struct task_struct *next)
2260 {
2261 	struct kvm_vcpu *vcpu = preempt_notifier_to_vcpu(pn);
2262 
2263 	kvm_arch_vcpu_put(vcpu);
2264 }
2265 
2266 int kvm_init(void *opaque, unsigned int vcpu_size,
2267 		  struct module *module)
2268 {
2269 	int r;
2270 	int cpu;
2271 
2272 	kvm_init_debug();
2273 
2274 	r = kvm_arch_init(opaque);
2275 	if (r)
2276 		goto out_fail;
2277 
2278 	bad_page = alloc_page(GFP_KERNEL | __GFP_ZERO);
2279 
2280 	if (bad_page == NULL) {
2281 		r = -ENOMEM;
2282 		goto out;
2283 	}
2284 
2285 	bad_pfn = page_to_pfn(bad_page);
2286 
2287 	if (!alloc_cpumask_var(&cpus_hardware_enabled, GFP_KERNEL)) {
2288 		r = -ENOMEM;
2289 		goto out_free_0;
2290 	}
2291 
2292 	r = kvm_arch_hardware_setup();
2293 	if (r < 0)
2294 		goto out_free_0a;
2295 
2296 	for_each_online_cpu(cpu) {
2297 		smp_call_function_single(cpu,
2298 				kvm_arch_check_processor_compat,
2299 				&r, 1);
2300 		if (r < 0)
2301 			goto out_free_1;
2302 	}
2303 
2304 	on_each_cpu(hardware_enable, NULL, 1);
2305 	r = register_cpu_notifier(&kvm_cpu_notifier);
2306 	if (r)
2307 		goto out_free_2;
2308 	register_reboot_notifier(&kvm_reboot_notifier);
2309 
2310 	r = sysdev_class_register(&kvm_sysdev_class);
2311 	if (r)
2312 		goto out_free_3;
2313 
2314 	r = sysdev_register(&kvm_sysdev);
2315 	if (r)
2316 		goto out_free_4;
2317 
2318 	/* A kmem cache lets us meet the alignment requirements of fx_save. */
2319 	kvm_vcpu_cache = kmem_cache_create("kvm_vcpu", vcpu_size,
2320 					   __alignof__(struct kvm_vcpu),
2321 					   0, NULL);
2322 	if (!kvm_vcpu_cache) {
2323 		r = -ENOMEM;
2324 		goto out_free_5;
2325 	}
2326 
2327 	kvm_chardev_ops.owner = module;
2328 	kvm_vm_fops.owner = module;
2329 	kvm_vcpu_fops.owner = module;
2330 
2331 	r = misc_register(&kvm_dev);
2332 	if (r) {
2333 		printk(KERN_ERR "kvm: misc device register failed\n");
2334 		goto out_free;
2335 	}
2336 
2337 	kvm_preempt_ops.sched_in = kvm_sched_in;
2338 	kvm_preempt_ops.sched_out = kvm_sched_out;
2339 #ifndef CONFIG_X86
2340 	msi2intx = 0;
2341 #endif
2342 
2343 	return 0;
2344 
2345 out_free:
2346 	kmem_cache_destroy(kvm_vcpu_cache);
2347 out_free_5:
2348 	sysdev_unregister(&kvm_sysdev);
2349 out_free_4:
2350 	sysdev_class_unregister(&kvm_sysdev_class);
2351 out_free_3:
2352 	unregister_reboot_notifier(&kvm_reboot_notifier);
2353 	unregister_cpu_notifier(&kvm_cpu_notifier);
2354 out_free_2:
2355 	on_each_cpu(hardware_disable, NULL, 1);
2356 out_free_1:
2357 	kvm_arch_hardware_unsetup();
2358 out_free_0a:
2359 	free_cpumask_var(cpus_hardware_enabled);
2360 out_free_0:
2361 	__free_page(bad_page);
2362 out:
2363 	kvm_arch_exit();
2364 	kvm_exit_debug();
2365 out_fail:
2366 	return r;
2367 }
2368 EXPORT_SYMBOL_GPL(kvm_init);
2369 
2370 void kvm_exit(void)
2371 {
2372 	kvm_trace_cleanup();
2373 	misc_deregister(&kvm_dev);
2374 	kmem_cache_destroy(kvm_vcpu_cache);
2375 	sysdev_unregister(&kvm_sysdev);
2376 	sysdev_class_unregister(&kvm_sysdev_class);
2377 	unregister_reboot_notifier(&kvm_reboot_notifier);
2378 	unregister_cpu_notifier(&kvm_cpu_notifier);
2379 	on_each_cpu(hardware_disable, NULL, 1);
2380 	kvm_arch_hardware_unsetup();
2381 	kvm_arch_exit();
2382 	kvm_exit_debug();
2383 	free_cpumask_var(cpus_hardware_enabled);
2384 	__free_page(bad_page);
2385 }
2386 EXPORT_SYMBOL_GPL(kvm_exit);
2387