xref: /linux/virt/kvm/kvm_main.c (revision 273b281fa22c293963ee3e6eec418f5dda2dbc83)
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 #include <linux/compat.h>
47 
48 #include <asm/processor.h>
49 #include <asm/io.h>
50 #include <asm/uaccess.h>
51 #include <asm/pgtable.h>
52 
53 #ifdef KVM_COALESCED_MMIO_PAGE_OFFSET
54 #include "coalesced_mmio.h"
55 #endif
56 
57 #define CREATE_TRACE_POINTS
58 #include <trace/events/kvm.h>
59 
60 MODULE_AUTHOR("Qumranet");
61 MODULE_LICENSE("GPL");
62 
63 /*
64  * Ordering of locks:
65  *
66  * 		kvm->slots_lock --> kvm->lock --> kvm->irq_lock
67  */
68 
69 DEFINE_SPINLOCK(kvm_lock);
70 LIST_HEAD(vm_list);
71 
72 static cpumask_var_t cpus_hardware_enabled;
73 static int kvm_usage_count = 0;
74 static atomic_t hardware_enable_failed;
75 
76 struct kmem_cache *kvm_vcpu_cache;
77 EXPORT_SYMBOL_GPL(kvm_vcpu_cache);
78 
79 static __read_mostly struct preempt_ops kvm_preempt_ops;
80 
81 struct dentry *kvm_debugfs_dir;
82 
83 static long kvm_vcpu_ioctl(struct file *file, unsigned int ioctl,
84 			   unsigned long arg);
85 static int hardware_enable_all(void);
86 static void hardware_disable_all(void);
87 
88 static bool kvm_rebooting;
89 
90 static bool largepages_enabled = true;
91 
92 inline int kvm_is_mmio_pfn(pfn_t pfn)
93 {
94 	if (pfn_valid(pfn)) {
95 		struct page *page = compound_head(pfn_to_page(pfn));
96 		return PageReserved(page);
97 	}
98 
99 	return true;
100 }
101 
102 /*
103  * Switches to specified vcpu, until a matching vcpu_put()
104  */
105 void vcpu_load(struct kvm_vcpu *vcpu)
106 {
107 	int cpu;
108 
109 	mutex_lock(&vcpu->mutex);
110 	cpu = get_cpu();
111 	preempt_notifier_register(&vcpu->preempt_notifier);
112 	kvm_arch_vcpu_load(vcpu, cpu);
113 	put_cpu();
114 }
115 
116 void vcpu_put(struct kvm_vcpu *vcpu)
117 {
118 	preempt_disable();
119 	kvm_arch_vcpu_put(vcpu);
120 	preempt_notifier_unregister(&vcpu->preempt_notifier);
121 	preempt_enable();
122 	mutex_unlock(&vcpu->mutex);
123 }
124 
125 static void ack_flush(void *_completed)
126 {
127 }
128 
129 static bool make_all_cpus_request(struct kvm *kvm, unsigned int req)
130 {
131 	int i, cpu, me;
132 	cpumask_var_t cpus;
133 	bool called = true;
134 	struct kvm_vcpu *vcpu;
135 
136 	zalloc_cpumask_var(&cpus, GFP_ATOMIC);
137 
138 	spin_lock(&kvm->requests_lock);
139 	me = smp_processor_id();
140 	kvm_for_each_vcpu(i, vcpu, kvm) {
141 		if (test_and_set_bit(req, &vcpu->requests))
142 			continue;
143 		cpu = vcpu->cpu;
144 		if (cpus != NULL && cpu != -1 && cpu != me)
145 			cpumask_set_cpu(cpu, cpus);
146 	}
147 	if (unlikely(cpus == NULL))
148 		smp_call_function_many(cpu_online_mask, ack_flush, NULL, 1);
149 	else if (!cpumask_empty(cpus))
150 		smp_call_function_many(cpus, ack_flush, NULL, 1);
151 	else
152 		called = false;
153 	spin_unlock(&kvm->requests_lock);
154 	free_cpumask_var(cpus);
155 	return called;
156 }
157 
158 void kvm_flush_remote_tlbs(struct kvm *kvm)
159 {
160 	if (make_all_cpus_request(kvm, KVM_REQ_TLB_FLUSH))
161 		++kvm->stat.remote_tlb_flush;
162 }
163 
164 void kvm_reload_remote_mmus(struct kvm *kvm)
165 {
166 	make_all_cpus_request(kvm, KVM_REQ_MMU_RELOAD);
167 }
168 
169 int kvm_vcpu_init(struct kvm_vcpu *vcpu, struct kvm *kvm, unsigned id)
170 {
171 	struct page *page;
172 	int r;
173 
174 	mutex_init(&vcpu->mutex);
175 	vcpu->cpu = -1;
176 	vcpu->kvm = kvm;
177 	vcpu->vcpu_id = id;
178 	init_waitqueue_head(&vcpu->wq);
179 
180 	page = alloc_page(GFP_KERNEL | __GFP_ZERO);
181 	if (!page) {
182 		r = -ENOMEM;
183 		goto fail;
184 	}
185 	vcpu->run = page_address(page);
186 
187 	r = kvm_arch_vcpu_init(vcpu);
188 	if (r < 0)
189 		goto fail_free_run;
190 	return 0;
191 
192 fail_free_run:
193 	free_page((unsigned long)vcpu->run);
194 fail:
195 	return r;
196 }
197 EXPORT_SYMBOL_GPL(kvm_vcpu_init);
198 
199 void kvm_vcpu_uninit(struct kvm_vcpu *vcpu)
200 {
201 	kvm_arch_vcpu_uninit(vcpu);
202 	free_page((unsigned long)vcpu->run);
203 }
204 EXPORT_SYMBOL_GPL(kvm_vcpu_uninit);
205 
206 #if defined(CONFIG_MMU_NOTIFIER) && defined(KVM_ARCH_WANT_MMU_NOTIFIER)
207 static inline struct kvm *mmu_notifier_to_kvm(struct mmu_notifier *mn)
208 {
209 	return container_of(mn, struct kvm, mmu_notifier);
210 }
211 
212 static void kvm_mmu_notifier_invalidate_page(struct mmu_notifier *mn,
213 					     struct mm_struct *mm,
214 					     unsigned long address)
215 {
216 	struct kvm *kvm = mmu_notifier_to_kvm(mn);
217 	int need_tlb_flush;
218 
219 	/*
220 	 * When ->invalidate_page runs, the linux pte has been zapped
221 	 * already but the page is still allocated until
222 	 * ->invalidate_page returns. So if we increase the sequence
223 	 * here the kvm page fault will notice if the spte can't be
224 	 * established because the page is going to be freed. If
225 	 * instead the kvm page fault establishes the spte before
226 	 * ->invalidate_page runs, kvm_unmap_hva will release it
227 	 * before returning.
228 	 *
229 	 * The sequence increase only need to be seen at spin_unlock
230 	 * time, and not at spin_lock time.
231 	 *
232 	 * Increasing the sequence after the spin_unlock would be
233 	 * unsafe because the kvm page fault could then establish the
234 	 * pte after kvm_unmap_hva returned, without noticing the page
235 	 * is going to be freed.
236 	 */
237 	spin_lock(&kvm->mmu_lock);
238 	kvm->mmu_notifier_seq++;
239 	need_tlb_flush = kvm_unmap_hva(kvm, address);
240 	spin_unlock(&kvm->mmu_lock);
241 
242 	/* we've to flush the tlb before the pages can be freed */
243 	if (need_tlb_flush)
244 		kvm_flush_remote_tlbs(kvm);
245 
246 }
247 
248 static void kvm_mmu_notifier_change_pte(struct mmu_notifier *mn,
249 					struct mm_struct *mm,
250 					unsigned long address,
251 					pte_t pte)
252 {
253 	struct kvm *kvm = mmu_notifier_to_kvm(mn);
254 
255 	spin_lock(&kvm->mmu_lock);
256 	kvm->mmu_notifier_seq++;
257 	kvm_set_spte_hva(kvm, address, pte);
258 	spin_unlock(&kvm->mmu_lock);
259 }
260 
261 static void kvm_mmu_notifier_invalidate_range_start(struct mmu_notifier *mn,
262 						    struct mm_struct *mm,
263 						    unsigned long start,
264 						    unsigned long end)
265 {
266 	struct kvm *kvm = mmu_notifier_to_kvm(mn);
267 	int need_tlb_flush = 0;
268 
269 	spin_lock(&kvm->mmu_lock);
270 	/*
271 	 * The count increase must become visible at unlock time as no
272 	 * spte can be established without taking the mmu_lock and
273 	 * count is also read inside the mmu_lock critical section.
274 	 */
275 	kvm->mmu_notifier_count++;
276 	for (; start < end; start += PAGE_SIZE)
277 		need_tlb_flush |= kvm_unmap_hva(kvm, start);
278 	spin_unlock(&kvm->mmu_lock);
279 
280 	/* we've to flush the tlb before the pages can be freed */
281 	if (need_tlb_flush)
282 		kvm_flush_remote_tlbs(kvm);
283 }
284 
285 static void kvm_mmu_notifier_invalidate_range_end(struct mmu_notifier *mn,
286 						  struct mm_struct *mm,
287 						  unsigned long start,
288 						  unsigned long end)
289 {
290 	struct kvm *kvm = mmu_notifier_to_kvm(mn);
291 
292 	spin_lock(&kvm->mmu_lock);
293 	/*
294 	 * This sequence increase will notify the kvm page fault that
295 	 * the page that is going to be mapped in the spte could have
296 	 * been freed.
297 	 */
298 	kvm->mmu_notifier_seq++;
299 	/*
300 	 * The above sequence increase must be visible before the
301 	 * below count decrease but both values are read by the kvm
302 	 * page fault under mmu_lock spinlock so we don't need to add
303 	 * a smb_wmb() here in between the two.
304 	 */
305 	kvm->mmu_notifier_count--;
306 	spin_unlock(&kvm->mmu_lock);
307 
308 	BUG_ON(kvm->mmu_notifier_count < 0);
309 }
310 
311 static int kvm_mmu_notifier_clear_flush_young(struct mmu_notifier *mn,
312 					      struct mm_struct *mm,
313 					      unsigned long address)
314 {
315 	struct kvm *kvm = mmu_notifier_to_kvm(mn);
316 	int young;
317 
318 	spin_lock(&kvm->mmu_lock);
319 	young = kvm_age_hva(kvm, address);
320 	spin_unlock(&kvm->mmu_lock);
321 
322 	if (young)
323 		kvm_flush_remote_tlbs(kvm);
324 
325 	return young;
326 }
327 
328 static void kvm_mmu_notifier_release(struct mmu_notifier *mn,
329 				     struct mm_struct *mm)
330 {
331 	struct kvm *kvm = mmu_notifier_to_kvm(mn);
332 	kvm_arch_flush_shadow(kvm);
333 }
334 
335 static const struct mmu_notifier_ops kvm_mmu_notifier_ops = {
336 	.invalidate_page	= kvm_mmu_notifier_invalidate_page,
337 	.invalidate_range_start	= kvm_mmu_notifier_invalidate_range_start,
338 	.invalidate_range_end	= kvm_mmu_notifier_invalidate_range_end,
339 	.clear_flush_young	= kvm_mmu_notifier_clear_flush_young,
340 	.change_pte		= kvm_mmu_notifier_change_pte,
341 	.release		= kvm_mmu_notifier_release,
342 };
343 #endif /* CONFIG_MMU_NOTIFIER && KVM_ARCH_WANT_MMU_NOTIFIER */
344 
345 static struct kvm *kvm_create_vm(void)
346 {
347 	int r = 0;
348 	struct kvm *kvm = kvm_arch_create_vm();
349 #ifdef KVM_COALESCED_MMIO_PAGE_OFFSET
350 	struct page *page;
351 #endif
352 
353 	if (IS_ERR(kvm))
354 		goto out;
355 
356 	r = hardware_enable_all();
357 	if (r)
358 		goto out_err_nodisable;
359 
360 #ifdef CONFIG_HAVE_KVM_IRQCHIP
361 	INIT_HLIST_HEAD(&kvm->mask_notifier_list);
362 	INIT_HLIST_HEAD(&kvm->irq_ack_notifier_list);
363 #endif
364 
365 #ifdef KVM_COALESCED_MMIO_PAGE_OFFSET
366 	page = alloc_page(GFP_KERNEL | __GFP_ZERO);
367 	if (!page) {
368 		r = -ENOMEM;
369 		goto out_err;
370 	}
371 	kvm->coalesced_mmio_ring =
372 			(struct kvm_coalesced_mmio_ring *)page_address(page);
373 #endif
374 
375 #if defined(CONFIG_MMU_NOTIFIER) && defined(KVM_ARCH_WANT_MMU_NOTIFIER)
376 	{
377 		kvm->mmu_notifier.ops = &kvm_mmu_notifier_ops;
378 		r = mmu_notifier_register(&kvm->mmu_notifier, current->mm);
379 		if (r) {
380 #ifdef KVM_COALESCED_MMIO_PAGE_OFFSET
381 			put_page(page);
382 #endif
383 			goto out_err;
384 		}
385 	}
386 #endif
387 
388 	kvm->mm = current->mm;
389 	atomic_inc(&kvm->mm->mm_count);
390 	spin_lock_init(&kvm->mmu_lock);
391 	spin_lock_init(&kvm->requests_lock);
392 	kvm_io_bus_init(&kvm->pio_bus);
393 	kvm_eventfd_init(kvm);
394 	mutex_init(&kvm->lock);
395 	mutex_init(&kvm->irq_lock);
396 	kvm_io_bus_init(&kvm->mmio_bus);
397 	init_rwsem(&kvm->slots_lock);
398 	atomic_set(&kvm->users_count, 1);
399 	spin_lock(&kvm_lock);
400 	list_add(&kvm->vm_list, &vm_list);
401 	spin_unlock(&kvm_lock);
402 #ifdef KVM_COALESCED_MMIO_PAGE_OFFSET
403 	kvm_coalesced_mmio_init(kvm);
404 #endif
405 out:
406 	return kvm;
407 
408 out_err:
409 	hardware_disable_all();
410 out_err_nodisable:
411 	kfree(kvm);
412 	return ERR_PTR(r);
413 }
414 
415 /*
416  * Free any memory in @free but not in @dont.
417  */
418 static void kvm_free_physmem_slot(struct kvm_memory_slot *free,
419 				  struct kvm_memory_slot *dont)
420 {
421 	int i;
422 
423 	if (!dont || free->rmap != dont->rmap)
424 		vfree(free->rmap);
425 
426 	if (!dont || free->dirty_bitmap != dont->dirty_bitmap)
427 		vfree(free->dirty_bitmap);
428 
429 
430 	for (i = 0; i < KVM_NR_PAGE_SIZES - 1; ++i) {
431 		if (!dont || free->lpage_info[i] != dont->lpage_info[i]) {
432 			vfree(free->lpage_info[i]);
433 			free->lpage_info[i] = NULL;
434 		}
435 	}
436 
437 	free->npages = 0;
438 	free->dirty_bitmap = NULL;
439 	free->rmap = NULL;
440 }
441 
442 void kvm_free_physmem(struct kvm *kvm)
443 {
444 	int i;
445 
446 	for (i = 0; i < kvm->nmemslots; ++i)
447 		kvm_free_physmem_slot(&kvm->memslots[i], NULL);
448 }
449 
450 static void kvm_destroy_vm(struct kvm *kvm)
451 {
452 	struct mm_struct *mm = kvm->mm;
453 
454 	kvm_arch_sync_events(kvm);
455 	spin_lock(&kvm_lock);
456 	list_del(&kvm->vm_list);
457 	spin_unlock(&kvm_lock);
458 	kvm_free_irq_routing(kvm);
459 	kvm_io_bus_destroy(&kvm->pio_bus);
460 	kvm_io_bus_destroy(&kvm->mmio_bus);
461 #ifdef KVM_COALESCED_MMIO_PAGE_OFFSET
462 	if (kvm->coalesced_mmio_ring != NULL)
463 		free_page((unsigned long)kvm->coalesced_mmio_ring);
464 #endif
465 #if defined(CONFIG_MMU_NOTIFIER) && defined(KVM_ARCH_WANT_MMU_NOTIFIER)
466 	mmu_notifier_unregister(&kvm->mmu_notifier, kvm->mm);
467 #else
468 	kvm_arch_flush_shadow(kvm);
469 #endif
470 	kvm_arch_destroy_vm(kvm);
471 	hardware_disable_all();
472 	mmdrop(mm);
473 }
474 
475 void kvm_get_kvm(struct kvm *kvm)
476 {
477 	atomic_inc(&kvm->users_count);
478 }
479 EXPORT_SYMBOL_GPL(kvm_get_kvm);
480 
481 void kvm_put_kvm(struct kvm *kvm)
482 {
483 	if (atomic_dec_and_test(&kvm->users_count))
484 		kvm_destroy_vm(kvm);
485 }
486 EXPORT_SYMBOL_GPL(kvm_put_kvm);
487 
488 
489 static int kvm_vm_release(struct inode *inode, struct file *filp)
490 {
491 	struct kvm *kvm = filp->private_data;
492 
493 	kvm_irqfd_release(kvm);
494 
495 	kvm_put_kvm(kvm);
496 	return 0;
497 }
498 
499 /*
500  * Allocate some memory and give it an address in the guest physical address
501  * space.
502  *
503  * Discontiguous memory is allowed, mostly for framebuffers.
504  *
505  * Must be called holding mmap_sem for write.
506  */
507 int __kvm_set_memory_region(struct kvm *kvm,
508 			    struct kvm_userspace_memory_region *mem,
509 			    int user_alloc)
510 {
511 	int r;
512 	gfn_t base_gfn;
513 	unsigned long npages;
514 	unsigned long i;
515 	struct kvm_memory_slot *memslot;
516 	struct kvm_memory_slot old, new;
517 
518 	r = -EINVAL;
519 	/* General sanity checks */
520 	if (mem->memory_size & (PAGE_SIZE - 1))
521 		goto out;
522 	if (mem->guest_phys_addr & (PAGE_SIZE - 1))
523 		goto out;
524 	if (user_alloc && (mem->userspace_addr & (PAGE_SIZE - 1)))
525 		goto out;
526 	if (mem->slot >= KVM_MEMORY_SLOTS + KVM_PRIVATE_MEM_SLOTS)
527 		goto out;
528 	if (mem->guest_phys_addr + mem->memory_size < mem->guest_phys_addr)
529 		goto out;
530 
531 	memslot = &kvm->memslots[mem->slot];
532 	base_gfn = mem->guest_phys_addr >> PAGE_SHIFT;
533 	npages = mem->memory_size >> PAGE_SHIFT;
534 
535 	if (!npages)
536 		mem->flags &= ~KVM_MEM_LOG_DIRTY_PAGES;
537 
538 	new = old = *memslot;
539 
540 	new.base_gfn = base_gfn;
541 	new.npages = npages;
542 	new.flags = mem->flags;
543 
544 	/* Disallow changing a memory slot's size. */
545 	r = -EINVAL;
546 	if (npages && old.npages && npages != old.npages)
547 		goto out_free;
548 
549 	/* Check for overlaps */
550 	r = -EEXIST;
551 	for (i = 0; i < KVM_MEMORY_SLOTS; ++i) {
552 		struct kvm_memory_slot *s = &kvm->memslots[i];
553 
554 		if (s == memslot || !s->npages)
555 			continue;
556 		if (!((base_gfn + npages <= s->base_gfn) ||
557 		      (base_gfn >= s->base_gfn + s->npages)))
558 			goto out_free;
559 	}
560 
561 	/* Free page dirty bitmap if unneeded */
562 	if (!(new.flags & KVM_MEM_LOG_DIRTY_PAGES))
563 		new.dirty_bitmap = NULL;
564 
565 	r = -ENOMEM;
566 
567 	/* Allocate if a slot is being created */
568 #ifndef CONFIG_S390
569 	if (npages && !new.rmap) {
570 		new.rmap = vmalloc(npages * sizeof(struct page *));
571 
572 		if (!new.rmap)
573 			goto out_free;
574 
575 		memset(new.rmap, 0, npages * sizeof(*new.rmap));
576 
577 		new.user_alloc = user_alloc;
578 		/*
579 		 * hva_to_rmmap() serialzies with the mmu_lock and to be
580 		 * safe it has to ignore memslots with !user_alloc &&
581 		 * !userspace_addr.
582 		 */
583 		if (user_alloc)
584 			new.userspace_addr = mem->userspace_addr;
585 		else
586 			new.userspace_addr = 0;
587 	}
588 	if (!npages)
589 		goto skip_lpage;
590 
591 	for (i = 0; i < KVM_NR_PAGE_SIZES - 1; ++i) {
592 		unsigned long ugfn;
593 		unsigned long j;
594 		int lpages;
595 		int level = i + 2;
596 
597 		/* Avoid unused variable warning if no large pages */
598 		(void)level;
599 
600 		if (new.lpage_info[i])
601 			continue;
602 
603 		lpages = 1 + (base_gfn + npages - 1) /
604 			     KVM_PAGES_PER_HPAGE(level);
605 		lpages -= base_gfn / KVM_PAGES_PER_HPAGE(level);
606 
607 		new.lpage_info[i] = vmalloc(lpages * sizeof(*new.lpage_info[i]));
608 
609 		if (!new.lpage_info[i])
610 			goto out_free;
611 
612 		memset(new.lpage_info[i], 0,
613 		       lpages * sizeof(*new.lpage_info[i]));
614 
615 		if (base_gfn % KVM_PAGES_PER_HPAGE(level))
616 			new.lpage_info[i][0].write_count = 1;
617 		if ((base_gfn+npages) % KVM_PAGES_PER_HPAGE(level))
618 			new.lpage_info[i][lpages - 1].write_count = 1;
619 		ugfn = new.userspace_addr >> PAGE_SHIFT;
620 		/*
621 		 * If the gfn and userspace address are not aligned wrt each
622 		 * other, or if explicitly asked to, disable large page
623 		 * support for this slot
624 		 */
625 		if ((base_gfn ^ ugfn) & (KVM_PAGES_PER_HPAGE(level) - 1) ||
626 		    !largepages_enabled)
627 			for (j = 0; j < lpages; ++j)
628 				new.lpage_info[i][j].write_count = 1;
629 	}
630 
631 skip_lpage:
632 
633 	/* Allocate page dirty bitmap if needed */
634 	if ((new.flags & KVM_MEM_LOG_DIRTY_PAGES) && !new.dirty_bitmap) {
635 		unsigned dirty_bytes = ALIGN(npages, BITS_PER_LONG) / 8;
636 
637 		new.dirty_bitmap = vmalloc(dirty_bytes);
638 		if (!new.dirty_bitmap)
639 			goto out_free;
640 		memset(new.dirty_bitmap, 0, dirty_bytes);
641 		if (old.npages)
642 			kvm_arch_flush_shadow(kvm);
643 	}
644 #else  /* not defined CONFIG_S390 */
645 	new.user_alloc = user_alloc;
646 	if (user_alloc)
647 		new.userspace_addr = mem->userspace_addr;
648 #endif /* not defined CONFIG_S390 */
649 
650 	if (!npages)
651 		kvm_arch_flush_shadow(kvm);
652 
653 	spin_lock(&kvm->mmu_lock);
654 	if (mem->slot >= kvm->nmemslots)
655 		kvm->nmemslots = mem->slot + 1;
656 
657 	*memslot = new;
658 	spin_unlock(&kvm->mmu_lock);
659 
660 	r = kvm_arch_set_memory_region(kvm, mem, old, user_alloc);
661 	if (r) {
662 		spin_lock(&kvm->mmu_lock);
663 		*memslot = old;
664 		spin_unlock(&kvm->mmu_lock);
665 		goto out_free;
666 	}
667 
668 	kvm_free_physmem_slot(&old, npages ? &new : NULL);
669 	/* Slot deletion case: we have to update the current slot */
670 	spin_lock(&kvm->mmu_lock);
671 	if (!npages)
672 		*memslot = old;
673 	spin_unlock(&kvm->mmu_lock);
674 #ifdef CONFIG_DMAR
675 	/* map the pages in iommu page table */
676 	r = kvm_iommu_map_pages(kvm, base_gfn, npages);
677 	if (r)
678 		goto out;
679 #endif
680 	return 0;
681 
682 out_free:
683 	kvm_free_physmem_slot(&new, &old);
684 out:
685 	return r;
686 
687 }
688 EXPORT_SYMBOL_GPL(__kvm_set_memory_region);
689 
690 int kvm_set_memory_region(struct kvm *kvm,
691 			  struct kvm_userspace_memory_region *mem,
692 			  int user_alloc)
693 {
694 	int r;
695 
696 	down_write(&kvm->slots_lock);
697 	r = __kvm_set_memory_region(kvm, mem, user_alloc);
698 	up_write(&kvm->slots_lock);
699 	return r;
700 }
701 EXPORT_SYMBOL_GPL(kvm_set_memory_region);
702 
703 int kvm_vm_ioctl_set_memory_region(struct kvm *kvm,
704 				   struct
705 				   kvm_userspace_memory_region *mem,
706 				   int user_alloc)
707 {
708 	if (mem->slot >= KVM_MEMORY_SLOTS)
709 		return -EINVAL;
710 	return kvm_set_memory_region(kvm, mem, user_alloc);
711 }
712 
713 int kvm_get_dirty_log(struct kvm *kvm,
714 			struct kvm_dirty_log *log, int *is_dirty)
715 {
716 	struct kvm_memory_slot *memslot;
717 	int r, i;
718 	int n;
719 	unsigned long any = 0;
720 
721 	r = -EINVAL;
722 	if (log->slot >= KVM_MEMORY_SLOTS)
723 		goto out;
724 
725 	memslot = &kvm->memslots[log->slot];
726 	r = -ENOENT;
727 	if (!memslot->dirty_bitmap)
728 		goto out;
729 
730 	n = ALIGN(memslot->npages, BITS_PER_LONG) / 8;
731 
732 	for (i = 0; !any && i < n/sizeof(long); ++i)
733 		any = memslot->dirty_bitmap[i];
734 
735 	r = -EFAULT;
736 	if (copy_to_user(log->dirty_bitmap, memslot->dirty_bitmap, n))
737 		goto out;
738 
739 	if (any)
740 		*is_dirty = 1;
741 
742 	r = 0;
743 out:
744 	return r;
745 }
746 
747 void kvm_disable_largepages(void)
748 {
749 	largepages_enabled = false;
750 }
751 EXPORT_SYMBOL_GPL(kvm_disable_largepages);
752 
753 int is_error_page(struct page *page)
754 {
755 	return page == bad_page;
756 }
757 EXPORT_SYMBOL_GPL(is_error_page);
758 
759 int is_error_pfn(pfn_t pfn)
760 {
761 	return pfn == bad_pfn;
762 }
763 EXPORT_SYMBOL_GPL(is_error_pfn);
764 
765 static inline unsigned long bad_hva(void)
766 {
767 	return PAGE_OFFSET;
768 }
769 
770 int kvm_is_error_hva(unsigned long addr)
771 {
772 	return addr == bad_hva();
773 }
774 EXPORT_SYMBOL_GPL(kvm_is_error_hva);
775 
776 struct kvm_memory_slot *gfn_to_memslot_unaliased(struct kvm *kvm, gfn_t gfn)
777 {
778 	int i;
779 
780 	for (i = 0; i < kvm->nmemslots; ++i) {
781 		struct kvm_memory_slot *memslot = &kvm->memslots[i];
782 
783 		if (gfn >= memslot->base_gfn
784 		    && gfn < memslot->base_gfn + memslot->npages)
785 			return memslot;
786 	}
787 	return NULL;
788 }
789 EXPORT_SYMBOL_GPL(gfn_to_memslot_unaliased);
790 
791 struct kvm_memory_slot *gfn_to_memslot(struct kvm *kvm, gfn_t gfn)
792 {
793 	gfn = unalias_gfn(kvm, gfn);
794 	return gfn_to_memslot_unaliased(kvm, gfn);
795 }
796 
797 int kvm_is_visible_gfn(struct kvm *kvm, gfn_t gfn)
798 {
799 	int i;
800 
801 	gfn = unalias_gfn(kvm, gfn);
802 	for (i = 0; i < KVM_MEMORY_SLOTS; ++i) {
803 		struct kvm_memory_slot *memslot = &kvm->memslots[i];
804 
805 		if (gfn >= memslot->base_gfn
806 		    && gfn < memslot->base_gfn + memslot->npages)
807 			return 1;
808 	}
809 	return 0;
810 }
811 EXPORT_SYMBOL_GPL(kvm_is_visible_gfn);
812 
813 unsigned long gfn_to_hva(struct kvm *kvm, gfn_t gfn)
814 {
815 	struct kvm_memory_slot *slot;
816 
817 	gfn = unalias_gfn(kvm, gfn);
818 	slot = gfn_to_memslot_unaliased(kvm, gfn);
819 	if (!slot)
820 		return bad_hva();
821 	return (slot->userspace_addr + (gfn - slot->base_gfn) * PAGE_SIZE);
822 }
823 EXPORT_SYMBOL_GPL(gfn_to_hva);
824 
825 pfn_t gfn_to_pfn(struct kvm *kvm, gfn_t gfn)
826 {
827 	struct page *page[1];
828 	unsigned long addr;
829 	int npages;
830 	pfn_t pfn;
831 
832 	might_sleep();
833 
834 	addr = gfn_to_hva(kvm, gfn);
835 	if (kvm_is_error_hva(addr)) {
836 		get_page(bad_page);
837 		return page_to_pfn(bad_page);
838 	}
839 
840 	npages = get_user_pages_fast(addr, 1, 1, page);
841 
842 	if (unlikely(npages != 1)) {
843 		struct vm_area_struct *vma;
844 
845 		down_read(&current->mm->mmap_sem);
846 		vma = find_vma(current->mm, addr);
847 
848 		if (vma == NULL || addr < vma->vm_start ||
849 		    !(vma->vm_flags & VM_PFNMAP)) {
850 			up_read(&current->mm->mmap_sem);
851 			get_page(bad_page);
852 			return page_to_pfn(bad_page);
853 		}
854 
855 		pfn = ((addr - vma->vm_start) >> PAGE_SHIFT) + vma->vm_pgoff;
856 		up_read(&current->mm->mmap_sem);
857 		BUG_ON(!kvm_is_mmio_pfn(pfn));
858 	} else
859 		pfn = page_to_pfn(page[0]);
860 
861 	return pfn;
862 }
863 
864 EXPORT_SYMBOL_GPL(gfn_to_pfn);
865 
866 struct page *gfn_to_page(struct kvm *kvm, gfn_t gfn)
867 {
868 	pfn_t pfn;
869 
870 	pfn = gfn_to_pfn(kvm, gfn);
871 	if (!kvm_is_mmio_pfn(pfn))
872 		return pfn_to_page(pfn);
873 
874 	WARN_ON(kvm_is_mmio_pfn(pfn));
875 
876 	get_page(bad_page);
877 	return bad_page;
878 }
879 
880 EXPORT_SYMBOL_GPL(gfn_to_page);
881 
882 void kvm_release_page_clean(struct page *page)
883 {
884 	kvm_release_pfn_clean(page_to_pfn(page));
885 }
886 EXPORT_SYMBOL_GPL(kvm_release_page_clean);
887 
888 void kvm_release_pfn_clean(pfn_t pfn)
889 {
890 	if (!kvm_is_mmio_pfn(pfn))
891 		put_page(pfn_to_page(pfn));
892 }
893 EXPORT_SYMBOL_GPL(kvm_release_pfn_clean);
894 
895 void kvm_release_page_dirty(struct page *page)
896 {
897 	kvm_release_pfn_dirty(page_to_pfn(page));
898 }
899 EXPORT_SYMBOL_GPL(kvm_release_page_dirty);
900 
901 void kvm_release_pfn_dirty(pfn_t pfn)
902 {
903 	kvm_set_pfn_dirty(pfn);
904 	kvm_release_pfn_clean(pfn);
905 }
906 EXPORT_SYMBOL_GPL(kvm_release_pfn_dirty);
907 
908 void kvm_set_page_dirty(struct page *page)
909 {
910 	kvm_set_pfn_dirty(page_to_pfn(page));
911 }
912 EXPORT_SYMBOL_GPL(kvm_set_page_dirty);
913 
914 void kvm_set_pfn_dirty(pfn_t pfn)
915 {
916 	if (!kvm_is_mmio_pfn(pfn)) {
917 		struct page *page = pfn_to_page(pfn);
918 		if (!PageReserved(page))
919 			SetPageDirty(page);
920 	}
921 }
922 EXPORT_SYMBOL_GPL(kvm_set_pfn_dirty);
923 
924 void kvm_set_pfn_accessed(pfn_t pfn)
925 {
926 	if (!kvm_is_mmio_pfn(pfn))
927 		mark_page_accessed(pfn_to_page(pfn));
928 }
929 EXPORT_SYMBOL_GPL(kvm_set_pfn_accessed);
930 
931 void kvm_get_pfn(pfn_t pfn)
932 {
933 	if (!kvm_is_mmio_pfn(pfn))
934 		get_page(pfn_to_page(pfn));
935 }
936 EXPORT_SYMBOL_GPL(kvm_get_pfn);
937 
938 static int next_segment(unsigned long len, int offset)
939 {
940 	if (len > PAGE_SIZE - offset)
941 		return PAGE_SIZE - offset;
942 	else
943 		return len;
944 }
945 
946 int kvm_read_guest_page(struct kvm *kvm, gfn_t gfn, void *data, int offset,
947 			int len)
948 {
949 	int r;
950 	unsigned long addr;
951 
952 	addr = gfn_to_hva(kvm, gfn);
953 	if (kvm_is_error_hva(addr))
954 		return -EFAULT;
955 	r = copy_from_user(data, (void __user *)addr + offset, len);
956 	if (r)
957 		return -EFAULT;
958 	return 0;
959 }
960 EXPORT_SYMBOL_GPL(kvm_read_guest_page);
961 
962 int kvm_read_guest(struct kvm *kvm, gpa_t gpa, void *data, unsigned long len)
963 {
964 	gfn_t gfn = gpa >> PAGE_SHIFT;
965 	int seg;
966 	int offset = offset_in_page(gpa);
967 	int ret;
968 
969 	while ((seg = next_segment(len, offset)) != 0) {
970 		ret = kvm_read_guest_page(kvm, gfn, data, offset, seg);
971 		if (ret < 0)
972 			return ret;
973 		offset = 0;
974 		len -= seg;
975 		data += seg;
976 		++gfn;
977 	}
978 	return 0;
979 }
980 EXPORT_SYMBOL_GPL(kvm_read_guest);
981 
982 int kvm_read_guest_atomic(struct kvm *kvm, gpa_t gpa, void *data,
983 			  unsigned long len)
984 {
985 	int r;
986 	unsigned long addr;
987 	gfn_t gfn = gpa >> PAGE_SHIFT;
988 	int offset = offset_in_page(gpa);
989 
990 	addr = gfn_to_hva(kvm, gfn);
991 	if (kvm_is_error_hva(addr))
992 		return -EFAULT;
993 	pagefault_disable();
994 	r = __copy_from_user_inatomic(data, (void __user *)addr + offset, len);
995 	pagefault_enable();
996 	if (r)
997 		return -EFAULT;
998 	return 0;
999 }
1000 EXPORT_SYMBOL(kvm_read_guest_atomic);
1001 
1002 int kvm_write_guest_page(struct kvm *kvm, gfn_t gfn, const void *data,
1003 			 int offset, int len)
1004 {
1005 	int r;
1006 	unsigned long addr;
1007 
1008 	addr = gfn_to_hva(kvm, gfn);
1009 	if (kvm_is_error_hva(addr))
1010 		return -EFAULT;
1011 	r = copy_to_user((void __user *)addr + offset, data, len);
1012 	if (r)
1013 		return -EFAULT;
1014 	mark_page_dirty(kvm, gfn);
1015 	return 0;
1016 }
1017 EXPORT_SYMBOL_GPL(kvm_write_guest_page);
1018 
1019 int kvm_write_guest(struct kvm *kvm, gpa_t gpa, const void *data,
1020 		    unsigned long len)
1021 {
1022 	gfn_t gfn = gpa >> PAGE_SHIFT;
1023 	int seg;
1024 	int offset = offset_in_page(gpa);
1025 	int ret;
1026 
1027 	while ((seg = next_segment(len, offset)) != 0) {
1028 		ret = kvm_write_guest_page(kvm, gfn, data, offset, seg);
1029 		if (ret < 0)
1030 			return ret;
1031 		offset = 0;
1032 		len -= seg;
1033 		data += seg;
1034 		++gfn;
1035 	}
1036 	return 0;
1037 }
1038 
1039 int kvm_clear_guest_page(struct kvm *kvm, gfn_t gfn, int offset, int len)
1040 {
1041 	return kvm_write_guest_page(kvm, gfn, empty_zero_page, offset, len);
1042 }
1043 EXPORT_SYMBOL_GPL(kvm_clear_guest_page);
1044 
1045 int kvm_clear_guest(struct kvm *kvm, gpa_t gpa, unsigned long len)
1046 {
1047 	gfn_t gfn = gpa >> PAGE_SHIFT;
1048 	int seg;
1049 	int offset = offset_in_page(gpa);
1050 	int ret;
1051 
1052         while ((seg = next_segment(len, offset)) != 0) {
1053 		ret = kvm_clear_guest_page(kvm, gfn, offset, seg);
1054 		if (ret < 0)
1055 			return ret;
1056 		offset = 0;
1057 		len -= seg;
1058 		++gfn;
1059 	}
1060 	return 0;
1061 }
1062 EXPORT_SYMBOL_GPL(kvm_clear_guest);
1063 
1064 void mark_page_dirty(struct kvm *kvm, gfn_t gfn)
1065 {
1066 	struct kvm_memory_slot *memslot;
1067 
1068 	gfn = unalias_gfn(kvm, gfn);
1069 	memslot = gfn_to_memslot_unaliased(kvm, gfn);
1070 	if (memslot && memslot->dirty_bitmap) {
1071 		unsigned long rel_gfn = gfn - memslot->base_gfn;
1072 
1073 		/* avoid RMW */
1074 		if (!test_bit(rel_gfn, memslot->dirty_bitmap))
1075 			set_bit(rel_gfn, memslot->dirty_bitmap);
1076 	}
1077 }
1078 
1079 /*
1080  * The vCPU has executed a HLT instruction with in-kernel mode enabled.
1081  */
1082 void kvm_vcpu_block(struct kvm_vcpu *vcpu)
1083 {
1084 	DEFINE_WAIT(wait);
1085 
1086 	for (;;) {
1087 		prepare_to_wait(&vcpu->wq, &wait, TASK_INTERRUPTIBLE);
1088 
1089 		if (kvm_arch_vcpu_runnable(vcpu)) {
1090 			set_bit(KVM_REQ_UNHALT, &vcpu->requests);
1091 			break;
1092 		}
1093 		if (kvm_cpu_has_pending_timer(vcpu))
1094 			break;
1095 		if (signal_pending(current))
1096 			break;
1097 
1098 		schedule();
1099 	}
1100 
1101 	finish_wait(&vcpu->wq, &wait);
1102 }
1103 
1104 void kvm_resched(struct kvm_vcpu *vcpu)
1105 {
1106 	if (!need_resched())
1107 		return;
1108 	cond_resched();
1109 }
1110 EXPORT_SYMBOL_GPL(kvm_resched);
1111 
1112 void kvm_vcpu_on_spin(struct kvm_vcpu *vcpu)
1113 {
1114 	ktime_t expires;
1115 	DEFINE_WAIT(wait);
1116 
1117 	prepare_to_wait(&vcpu->wq, &wait, TASK_INTERRUPTIBLE);
1118 
1119 	/* Sleep for 100 us, and hope lock-holder got scheduled */
1120 	expires = ktime_add_ns(ktime_get(), 100000UL);
1121 	schedule_hrtimeout(&expires, HRTIMER_MODE_ABS);
1122 
1123 	finish_wait(&vcpu->wq, &wait);
1124 }
1125 EXPORT_SYMBOL_GPL(kvm_vcpu_on_spin);
1126 
1127 static int kvm_vcpu_fault(struct vm_area_struct *vma, struct vm_fault *vmf)
1128 {
1129 	struct kvm_vcpu *vcpu = vma->vm_file->private_data;
1130 	struct page *page;
1131 
1132 	if (vmf->pgoff == 0)
1133 		page = virt_to_page(vcpu->run);
1134 #ifdef CONFIG_X86
1135 	else if (vmf->pgoff == KVM_PIO_PAGE_OFFSET)
1136 		page = virt_to_page(vcpu->arch.pio_data);
1137 #endif
1138 #ifdef KVM_COALESCED_MMIO_PAGE_OFFSET
1139 	else if (vmf->pgoff == KVM_COALESCED_MMIO_PAGE_OFFSET)
1140 		page = virt_to_page(vcpu->kvm->coalesced_mmio_ring);
1141 #endif
1142 	else
1143 		return VM_FAULT_SIGBUS;
1144 	get_page(page);
1145 	vmf->page = page;
1146 	return 0;
1147 }
1148 
1149 static const struct vm_operations_struct kvm_vcpu_vm_ops = {
1150 	.fault = kvm_vcpu_fault,
1151 };
1152 
1153 static int kvm_vcpu_mmap(struct file *file, struct vm_area_struct *vma)
1154 {
1155 	vma->vm_ops = &kvm_vcpu_vm_ops;
1156 	return 0;
1157 }
1158 
1159 static int kvm_vcpu_release(struct inode *inode, struct file *filp)
1160 {
1161 	struct kvm_vcpu *vcpu = filp->private_data;
1162 
1163 	kvm_put_kvm(vcpu->kvm);
1164 	return 0;
1165 }
1166 
1167 static struct file_operations kvm_vcpu_fops = {
1168 	.release        = kvm_vcpu_release,
1169 	.unlocked_ioctl = kvm_vcpu_ioctl,
1170 	.compat_ioctl   = kvm_vcpu_ioctl,
1171 	.mmap           = kvm_vcpu_mmap,
1172 };
1173 
1174 /*
1175  * Allocates an inode for the vcpu.
1176  */
1177 static int create_vcpu_fd(struct kvm_vcpu *vcpu)
1178 {
1179 	return anon_inode_getfd("kvm-vcpu", &kvm_vcpu_fops, vcpu, 0);
1180 }
1181 
1182 /*
1183  * Creates some virtual cpus.  Good luck creating more than one.
1184  */
1185 static int kvm_vm_ioctl_create_vcpu(struct kvm *kvm, u32 id)
1186 {
1187 	int r;
1188 	struct kvm_vcpu *vcpu, *v;
1189 
1190 	vcpu = kvm_arch_vcpu_create(kvm, id);
1191 	if (IS_ERR(vcpu))
1192 		return PTR_ERR(vcpu);
1193 
1194 	preempt_notifier_init(&vcpu->preempt_notifier, &kvm_preempt_ops);
1195 
1196 	r = kvm_arch_vcpu_setup(vcpu);
1197 	if (r)
1198 		return r;
1199 
1200 	mutex_lock(&kvm->lock);
1201 	if (atomic_read(&kvm->online_vcpus) == KVM_MAX_VCPUS) {
1202 		r = -EINVAL;
1203 		goto vcpu_destroy;
1204 	}
1205 
1206 	kvm_for_each_vcpu(r, v, kvm)
1207 		if (v->vcpu_id == id) {
1208 			r = -EEXIST;
1209 			goto vcpu_destroy;
1210 		}
1211 
1212 	BUG_ON(kvm->vcpus[atomic_read(&kvm->online_vcpus)]);
1213 
1214 	/* Now it's all set up, let userspace reach it */
1215 	kvm_get_kvm(kvm);
1216 	r = create_vcpu_fd(vcpu);
1217 	if (r < 0) {
1218 		kvm_put_kvm(kvm);
1219 		goto vcpu_destroy;
1220 	}
1221 
1222 	kvm->vcpus[atomic_read(&kvm->online_vcpus)] = vcpu;
1223 	smp_wmb();
1224 	atomic_inc(&kvm->online_vcpus);
1225 
1226 #ifdef CONFIG_KVM_APIC_ARCHITECTURE
1227 	if (kvm->bsp_vcpu_id == id)
1228 		kvm->bsp_vcpu = vcpu;
1229 #endif
1230 	mutex_unlock(&kvm->lock);
1231 	return r;
1232 
1233 vcpu_destroy:
1234 	mutex_unlock(&kvm->lock);
1235 	kvm_arch_vcpu_destroy(vcpu);
1236 	return r;
1237 }
1238 
1239 static int kvm_vcpu_ioctl_set_sigmask(struct kvm_vcpu *vcpu, sigset_t *sigset)
1240 {
1241 	if (sigset) {
1242 		sigdelsetmask(sigset, sigmask(SIGKILL)|sigmask(SIGSTOP));
1243 		vcpu->sigset_active = 1;
1244 		vcpu->sigset = *sigset;
1245 	} else
1246 		vcpu->sigset_active = 0;
1247 	return 0;
1248 }
1249 
1250 static long kvm_vcpu_ioctl(struct file *filp,
1251 			   unsigned int ioctl, unsigned long arg)
1252 {
1253 	struct kvm_vcpu *vcpu = filp->private_data;
1254 	void __user *argp = (void __user *)arg;
1255 	int r;
1256 	struct kvm_fpu *fpu = NULL;
1257 	struct kvm_sregs *kvm_sregs = NULL;
1258 
1259 	if (vcpu->kvm->mm != current->mm)
1260 		return -EIO;
1261 	switch (ioctl) {
1262 	case KVM_RUN:
1263 		r = -EINVAL;
1264 		if (arg)
1265 			goto out;
1266 		r = kvm_arch_vcpu_ioctl_run(vcpu, vcpu->run);
1267 		break;
1268 	case KVM_GET_REGS: {
1269 		struct kvm_regs *kvm_regs;
1270 
1271 		r = -ENOMEM;
1272 		kvm_regs = kzalloc(sizeof(struct kvm_regs), GFP_KERNEL);
1273 		if (!kvm_regs)
1274 			goto out;
1275 		r = kvm_arch_vcpu_ioctl_get_regs(vcpu, kvm_regs);
1276 		if (r)
1277 			goto out_free1;
1278 		r = -EFAULT;
1279 		if (copy_to_user(argp, kvm_regs, sizeof(struct kvm_regs)))
1280 			goto out_free1;
1281 		r = 0;
1282 out_free1:
1283 		kfree(kvm_regs);
1284 		break;
1285 	}
1286 	case KVM_SET_REGS: {
1287 		struct kvm_regs *kvm_regs;
1288 
1289 		r = -ENOMEM;
1290 		kvm_regs = kzalloc(sizeof(struct kvm_regs), GFP_KERNEL);
1291 		if (!kvm_regs)
1292 			goto out;
1293 		r = -EFAULT;
1294 		if (copy_from_user(kvm_regs, argp, sizeof(struct kvm_regs)))
1295 			goto out_free2;
1296 		r = kvm_arch_vcpu_ioctl_set_regs(vcpu, kvm_regs);
1297 		if (r)
1298 			goto out_free2;
1299 		r = 0;
1300 out_free2:
1301 		kfree(kvm_regs);
1302 		break;
1303 	}
1304 	case KVM_GET_SREGS: {
1305 		kvm_sregs = kzalloc(sizeof(struct kvm_sregs), GFP_KERNEL);
1306 		r = -ENOMEM;
1307 		if (!kvm_sregs)
1308 			goto out;
1309 		r = kvm_arch_vcpu_ioctl_get_sregs(vcpu, kvm_sregs);
1310 		if (r)
1311 			goto out;
1312 		r = -EFAULT;
1313 		if (copy_to_user(argp, kvm_sregs, sizeof(struct kvm_sregs)))
1314 			goto out;
1315 		r = 0;
1316 		break;
1317 	}
1318 	case KVM_SET_SREGS: {
1319 		kvm_sregs = kmalloc(sizeof(struct kvm_sregs), GFP_KERNEL);
1320 		r = -ENOMEM;
1321 		if (!kvm_sregs)
1322 			goto out;
1323 		r = -EFAULT;
1324 		if (copy_from_user(kvm_sregs, argp, sizeof(struct kvm_sregs)))
1325 			goto out;
1326 		r = kvm_arch_vcpu_ioctl_set_sregs(vcpu, kvm_sregs);
1327 		if (r)
1328 			goto out;
1329 		r = 0;
1330 		break;
1331 	}
1332 	case KVM_GET_MP_STATE: {
1333 		struct kvm_mp_state mp_state;
1334 
1335 		r = kvm_arch_vcpu_ioctl_get_mpstate(vcpu, &mp_state);
1336 		if (r)
1337 			goto out;
1338 		r = -EFAULT;
1339 		if (copy_to_user(argp, &mp_state, sizeof mp_state))
1340 			goto out;
1341 		r = 0;
1342 		break;
1343 	}
1344 	case KVM_SET_MP_STATE: {
1345 		struct kvm_mp_state mp_state;
1346 
1347 		r = -EFAULT;
1348 		if (copy_from_user(&mp_state, argp, sizeof mp_state))
1349 			goto out;
1350 		r = kvm_arch_vcpu_ioctl_set_mpstate(vcpu, &mp_state);
1351 		if (r)
1352 			goto out;
1353 		r = 0;
1354 		break;
1355 	}
1356 	case KVM_TRANSLATE: {
1357 		struct kvm_translation tr;
1358 
1359 		r = -EFAULT;
1360 		if (copy_from_user(&tr, argp, sizeof tr))
1361 			goto out;
1362 		r = kvm_arch_vcpu_ioctl_translate(vcpu, &tr);
1363 		if (r)
1364 			goto out;
1365 		r = -EFAULT;
1366 		if (copy_to_user(argp, &tr, sizeof tr))
1367 			goto out;
1368 		r = 0;
1369 		break;
1370 	}
1371 	case KVM_SET_GUEST_DEBUG: {
1372 		struct kvm_guest_debug dbg;
1373 
1374 		r = -EFAULT;
1375 		if (copy_from_user(&dbg, argp, sizeof dbg))
1376 			goto out;
1377 		r = kvm_arch_vcpu_ioctl_set_guest_debug(vcpu, &dbg);
1378 		if (r)
1379 			goto out;
1380 		r = 0;
1381 		break;
1382 	}
1383 	case KVM_SET_SIGNAL_MASK: {
1384 		struct kvm_signal_mask __user *sigmask_arg = argp;
1385 		struct kvm_signal_mask kvm_sigmask;
1386 		sigset_t sigset, *p;
1387 
1388 		p = NULL;
1389 		if (argp) {
1390 			r = -EFAULT;
1391 			if (copy_from_user(&kvm_sigmask, argp,
1392 					   sizeof kvm_sigmask))
1393 				goto out;
1394 			r = -EINVAL;
1395 			if (kvm_sigmask.len != sizeof sigset)
1396 				goto out;
1397 			r = -EFAULT;
1398 			if (copy_from_user(&sigset, sigmask_arg->sigset,
1399 					   sizeof sigset))
1400 				goto out;
1401 			p = &sigset;
1402 		}
1403 		r = kvm_vcpu_ioctl_set_sigmask(vcpu, &sigset);
1404 		break;
1405 	}
1406 	case KVM_GET_FPU: {
1407 		fpu = kzalloc(sizeof(struct kvm_fpu), GFP_KERNEL);
1408 		r = -ENOMEM;
1409 		if (!fpu)
1410 			goto out;
1411 		r = kvm_arch_vcpu_ioctl_get_fpu(vcpu, fpu);
1412 		if (r)
1413 			goto out;
1414 		r = -EFAULT;
1415 		if (copy_to_user(argp, fpu, sizeof(struct kvm_fpu)))
1416 			goto out;
1417 		r = 0;
1418 		break;
1419 	}
1420 	case KVM_SET_FPU: {
1421 		fpu = kmalloc(sizeof(struct kvm_fpu), GFP_KERNEL);
1422 		r = -ENOMEM;
1423 		if (!fpu)
1424 			goto out;
1425 		r = -EFAULT;
1426 		if (copy_from_user(fpu, argp, sizeof(struct kvm_fpu)))
1427 			goto out;
1428 		r = kvm_arch_vcpu_ioctl_set_fpu(vcpu, fpu);
1429 		if (r)
1430 			goto out;
1431 		r = 0;
1432 		break;
1433 	}
1434 	default:
1435 		r = kvm_arch_vcpu_ioctl(filp, ioctl, arg);
1436 	}
1437 out:
1438 	kfree(fpu);
1439 	kfree(kvm_sregs);
1440 	return r;
1441 }
1442 
1443 static long kvm_vm_ioctl(struct file *filp,
1444 			   unsigned int ioctl, unsigned long arg)
1445 {
1446 	struct kvm *kvm = filp->private_data;
1447 	void __user *argp = (void __user *)arg;
1448 	int r;
1449 
1450 	if (kvm->mm != current->mm)
1451 		return -EIO;
1452 	switch (ioctl) {
1453 	case KVM_CREATE_VCPU:
1454 		r = kvm_vm_ioctl_create_vcpu(kvm, arg);
1455 		if (r < 0)
1456 			goto out;
1457 		break;
1458 	case KVM_SET_USER_MEMORY_REGION: {
1459 		struct kvm_userspace_memory_region kvm_userspace_mem;
1460 
1461 		r = -EFAULT;
1462 		if (copy_from_user(&kvm_userspace_mem, argp,
1463 						sizeof kvm_userspace_mem))
1464 			goto out;
1465 
1466 		r = kvm_vm_ioctl_set_memory_region(kvm, &kvm_userspace_mem, 1);
1467 		if (r)
1468 			goto out;
1469 		break;
1470 	}
1471 	case KVM_GET_DIRTY_LOG: {
1472 		struct kvm_dirty_log log;
1473 
1474 		r = -EFAULT;
1475 		if (copy_from_user(&log, argp, sizeof log))
1476 			goto out;
1477 		r = kvm_vm_ioctl_get_dirty_log(kvm, &log);
1478 		if (r)
1479 			goto out;
1480 		break;
1481 	}
1482 #ifdef KVM_COALESCED_MMIO_PAGE_OFFSET
1483 	case KVM_REGISTER_COALESCED_MMIO: {
1484 		struct kvm_coalesced_mmio_zone zone;
1485 		r = -EFAULT;
1486 		if (copy_from_user(&zone, argp, sizeof zone))
1487 			goto out;
1488 		r = -ENXIO;
1489 		r = kvm_vm_ioctl_register_coalesced_mmio(kvm, &zone);
1490 		if (r)
1491 			goto out;
1492 		r = 0;
1493 		break;
1494 	}
1495 	case KVM_UNREGISTER_COALESCED_MMIO: {
1496 		struct kvm_coalesced_mmio_zone zone;
1497 		r = -EFAULT;
1498 		if (copy_from_user(&zone, argp, sizeof zone))
1499 			goto out;
1500 		r = -ENXIO;
1501 		r = kvm_vm_ioctl_unregister_coalesced_mmio(kvm, &zone);
1502 		if (r)
1503 			goto out;
1504 		r = 0;
1505 		break;
1506 	}
1507 #endif
1508 	case KVM_IRQFD: {
1509 		struct kvm_irqfd data;
1510 
1511 		r = -EFAULT;
1512 		if (copy_from_user(&data, argp, sizeof data))
1513 			goto out;
1514 		r = kvm_irqfd(kvm, data.fd, data.gsi, data.flags);
1515 		break;
1516 	}
1517 	case KVM_IOEVENTFD: {
1518 		struct kvm_ioeventfd data;
1519 
1520 		r = -EFAULT;
1521 		if (copy_from_user(&data, argp, sizeof data))
1522 			goto out;
1523 		r = kvm_ioeventfd(kvm, &data);
1524 		break;
1525 	}
1526 #ifdef CONFIG_KVM_APIC_ARCHITECTURE
1527 	case KVM_SET_BOOT_CPU_ID:
1528 		r = 0;
1529 		mutex_lock(&kvm->lock);
1530 		if (atomic_read(&kvm->online_vcpus) != 0)
1531 			r = -EBUSY;
1532 		else
1533 			kvm->bsp_vcpu_id = arg;
1534 		mutex_unlock(&kvm->lock);
1535 		break;
1536 #endif
1537 	default:
1538 		r = kvm_arch_vm_ioctl(filp, ioctl, arg);
1539 		if (r == -ENOTTY)
1540 			r = kvm_vm_ioctl_assigned_device(kvm, ioctl, arg);
1541 	}
1542 out:
1543 	return r;
1544 }
1545 
1546 #ifdef CONFIG_COMPAT
1547 struct compat_kvm_dirty_log {
1548 	__u32 slot;
1549 	__u32 padding1;
1550 	union {
1551 		compat_uptr_t dirty_bitmap; /* one bit per page */
1552 		__u64 padding2;
1553 	};
1554 };
1555 
1556 static long kvm_vm_compat_ioctl(struct file *filp,
1557 			   unsigned int ioctl, unsigned long arg)
1558 {
1559 	struct kvm *kvm = filp->private_data;
1560 	int r;
1561 
1562 	if (kvm->mm != current->mm)
1563 		return -EIO;
1564 	switch (ioctl) {
1565 	case KVM_GET_DIRTY_LOG: {
1566 		struct compat_kvm_dirty_log compat_log;
1567 		struct kvm_dirty_log log;
1568 
1569 		r = -EFAULT;
1570 		if (copy_from_user(&compat_log, (void __user *)arg,
1571 				   sizeof(compat_log)))
1572 			goto out;
1573 		log.slot	 = compat_log.slot;
1574 		log.padding1	 = compat_log.padding1;
1575 		log.padding2	 = compat_log.padding2;
1576 		log.dirty_bitmap = compat_ptr(compat_log.dirty_bitmap);
1577 
1578 		r = kvm_vm_ioctl_get_dirty_log(kvm, &log);
1579 		if (r)
1580 			goto out;
1581 		break;
1582 	}
1583 	default:
1584 		r = kvm_vm_ioctl(filp, ioctl, arg);
1585 	}
1586 
1587 out:
1588 	return r;
1589 }
1590 #endif
1591 
1592 static int kvm_vm_fault(struct vm_area_struct *vma, struct vm_fault *vmf)
1593 {
1594 	struct page *page[1];
1595 	unsigned long addr;
1596 	int npages;
1597 	gfn_t gfn = vmf->pgoff;
1598 	struct kvm *kvm = vma->vm_file->private_data;
1599 
1600 	addr = gfn_to_hva(kvm, gfn);
1601 	if (kvm_is_error_hva(addr))
1602 		return VM_FAULT_SIGBUS;
1603 
1604 	npages = get_user_pages(current, current->mm, addr, 1, 1, 0, page,
1605 				NULL);
1606 	if (unlikely(npages != 1))
1607 		return VM_FAULT_SIGBUS;
1608 
1609 	vmf->page = page[0];
1610 	return 0;
1611 }
1612 
1613 static const struct vm_operations_struct kvm_vm_vm_ops = {
1614 	.fault = kvm_vm_fault,
1615 };
1616 
1617 static int kvm_vm_mmap(struct file *file, struct vm_area_struct *vma)
1618 {
1619 	vma->vm_ops = &kvm_vm_vm_ops;
1620 	return 0;
1621 }
1622 
1623 static struct file_operations kvm_vm_fops = {
1624 	.release        = kvm_vm_release,
1625 	.unlocked_ioctl = kvm_vm_ioctl,
1626 #ifdef CONFIG_COMPAT
1627 	.compat_ioctl   = kvm_vm_compat_ioctl,
1628 #endif
1629 	.mmap           = kvm_vm_mmap,
1630 };
1631 
1632 static int kvm_dev_ioctl_create_vm(void)
1633 {
1634 	int fd;
1635 	struct kvm *kvm;
1636 
1637 	kvm = kvm_create_vm();
1638 	if (IS_ERR(kvm))
1639 		return PTR_ERR(kvm);
1640 	fd = anon_inode_getfd("kvm-vm", &kvm_vm_fops, kvm, 0);
1641 	if (fd < 0)
1642 		kvm_put_kvm(kvm);
1643 
1644 	return fd;
1645 }
1646 
1647 static long kvm_dev_ioctl_check_extension_generic(long arg)
1648 {
1649 	switch (arg) {
1650 	case KVM_CAP_USER_MEMORY:
1651 	case KVM_CAP_DESTROY_MEMORY_REGION_WORKS:
1652 	case KVM_CAP_JOIN_MEMORY_REGIONS_WORKS:
1653 #ifdef CONFIG_KVM_APIC_ARCHITECTURE
1654 	case KVM_CAP_SET_BOOT_CPU_ID:
1655 #endif
1656 	case KVM_CAP_INTERNAL_ERROR_DATA:
1657 		return 1;
1658 #ifdef CONFIG_HAVE_KVM_IRQCHIP
1659 	case KVM_CAP_IRQ_ROUTING:
1660 		return KVM_MAX_IRQ_ROUTES;
1661 #endif
1662 	default:
1663 		break;
1664 	}
1665 	return kvm_dev_ioctl_check_extension(arg);
1666 }
1667 
1668 static long kvm_dev_ioctl(struct file *filp,
1669 			  unsigned int ioctl, unsigned long arg)
1670 {
1671 	long r = -EINVAL;
1672 
1673 	switch (ioctl) {
1674 	case KVM_GET_API_VERSION:
1675 		r = -EINVAL;
1676 		if (arg)
1677 			goto out;
1678 		r = KVM_API_VERSION;
1679 		break;
1680 	case KVM_CREATE_VM:
1681 		r = -EINVAL;
1682 		if (arg)
1683 			goto out;
1684 		r = kvm_dev_ioctl_create_vm();
1685 		break;
1686 	case KVM_CHECK_EXTENSION:
1687 		r = kvm_dev_ioctl_check_extension_generic(arg);
1688 		break;
1689 	case KVM_GET_VCPU_MMAP_SIZE:
1690 		r = -EINVAL;
1691 		if (arg)
1692 			goto out;
1693 		r = PAGE_SIZE;     /* struct kvm_run */
1694 #ifdef CONFIG_X86
1695 		r += PAGE_SIZE;    /* pio data page */
1696 #endif
1697 #ifdef KVM_COALESCED_MMIO_PAGE_OFFSET
1698 		r += PAGE_SIZE;    /* coalesced mmio ring page */
1699 #endif
1700 		break;
1701 	case KVM_TRACE_ENABLE:
1702 	case KVM_TRACE_PAUSE:
1703 	case KVM_TRACE_DISABLE:
1704 		r = -EOPNOTSUPP;
1705 		break;
1706 	default:
1707 		return kvm_arch_dev_ioctl(filp, ioctl, arg);
1708 	}
1709 out:
1710 	return r;
1711 }
1712 
1713 static struct file_operations kvm_chardev_ops = {
1714 	.unlocked_ioctl = kvm_dev_ioctl,
1715 	.compat_ioctl   = kvm_dev_ioctl,
1716 };
1717 
1718 static struct miscdevice kvm_dev = {
1719 	KVM_MINOR,
1720 	"kvm",
1721 	&kvm_chardev_ops,
1722 };
1723 
1724 static void hardware_enable(void *junk)
1725 {
1726 	int cpu = raw_smp_processor_id();
1727 	int r;
1728 
1729 	if (cpumask_test_cpu(cpu, cpus_hardware_enabled))
1730 		return;
1731 
1732 	cpumask_set_cpu(cpu, cpus_hardware_enabled);
1733 
1734 	r = kvm_arch_hardware_enable(NULL);
1735 
1736 	if (r) {
1737 		cpumask_clear_cpu(cpu, cpus_hardware_enabled);
1738 		atomic_inc(&hardware_enable_failed);
1739 		printk(KERN_INFO "kvm: enabling virtualization on "
1740 				 "CPU%d failed\n", cpu);
1741 	}
1742 }
1743 
1744 static void hardware_disable(void *junk)
1745 {
1746 	int cpu = raw_smp_processor_id();
1747 
1748 	if (!cpumask_test_cpu(cpu, cpus_hardware_enabled))
1749 		return;
1750 	cpumask_clear_cpu(cpu, cpus_hardware_enabled);
1751 	kvm_arch_hardware_disable(NULL);
1752 }
1753 
1754 static void hardware_disable_all_nolock(void)
1755 {
1756 	BUG_ON(!kvm_usage_count);
1757 
1758 	kvm_usage_count--;
1759 	if (!kvm_usage_count)
1760 		on_each_cpu(hardware_disable, NULL, 1);
1761 }
1762 
1763 static void hardware_disable_all(void)
1764 {
1765 	spin_lock(&kvm_lock);
1766 	hardware_disable_all_nolock();
1767 	spin_unlock(&kvm_lock);
1768 }
1769 
1770 static int hardware_enable_all(void)
1771 {
1772 	int r = 0;
1773 
1774 	spin_lock(&kvm_lock);
1775 
1776 	kvm_usage_count++;
1777 	if (kvm_usage_count == 1) {
1778 		atomic_set(&hardware_enable_failed, 0);
1779 		on_each_cpu(hardware_enable, NULL, 1);
1780 
1781 		if (atomic_read(&hardware_enable_failed)) {
1782 			hardware_disable_all_nolock();
1783 			r = -EBUSY;
1784 		}
1785 	}
1786 
1787 	spin_unlock(&kvm_lock);
1788 
1789 	return r;
1790 }
1791 
1792 static int kvm_cpu_hotplug(struct notifier_block *notifier, unsigned long val,
1793 			   void *v)
1794 {
1795 	int cpu = (long)v;
1796 
1797 	if (!kvm_usage_count)
1798 		return NOTIFY_OK;
1799 
1800 	val &= ~CPU_TASKS_FROZEN;
1801 	switch (val) {
1802 	case CPU_DYING:
1803 		printk(KERN_INFO "kvm: disabling virtualization on CPU%d\n",
1804 		       cpu);
1805 		hardware_disable(NULL);
1806 		break;
1807 	case CPU_UP_CANCELED:
1808 		printk(KERN_INFO "kvm: disabling virtualization on CPU%d\n",
1809 		       cpu);
1810 		smp_call_function_single(cpu, hardware_disable, NULL, 1);
1811 		break;
1812 	case CPU_ONLINE:
1813 		printk(KERN_INFO "kvm: enabling virtualization on CPU%d\n",
1814 		       cpu);
1815 		smp_call_function_single(cpu, hardware_enable, NULL, 1);
1816 		break;
1817 	}
1818 	return NOTIFY_OK;
1819 }
1820 
1821 
1822 asmlinkage void kvm_handle_fault_on_reboot(void)
1823 {
1824 	if (kvm_rebooting)
1825 		/* spin while reset goes on */
1826 		while (true)
1827 			;
1828 	/* Fault while not rebooting.  We want the trace. */
1829 	BUG();
1830 }
1831 EXPORT_SYMBOL_GPL(kvm_handle_fault_on_reboot);
1832 
1833 static int kvm_reboot(struct notifier_block *notifier, unsigned long val,
1834 		      void *v)
1835 {
1836 	/*
1837 	 * Some (well, at least mine) BIOSes hang on reboot if
1838 	 * in vmx root mode.
1839 	 *
1840 	 * And Intel TXT required VMX off for all cpu when system shutdown.
1841 	 */
1842 	printk(KERN_INFO "kvm: exiting hardware virtualization\n");
1843 	kvm_rebooting = true;
1844 	on_each_cpu(hardware_disable, NULL, 1);
1845 	return NOTIFY_OK;
1846 }
1847 
1848 static struct notifier_block kvm_reboot_notifier = {
1849 	.notifier_call = kvm_reboot,
1850 	.priority = 0,
1851 };
1852 
1853 void kvm_io_bus_init(struct kvm_io_bus *bus)
1854 {
1855 	memset(bus, 0, sizeof(*bus));
1856 }
1857 
1858 void kvm_io_bus_destroy(struct kvm_io_bus *bus)
1859 {
1860 	int i;
1861 
1862 	for (i = 0; i < bus->dev_count; i++) {
1863 		struct kvm_io_device *pos = bus->devs[i];
1864 
1865 		kvm_iodevice_destructor(pos);
1866 	}
1867 }
1868 
1869 /* kvm_io_bus_write - called under kvm->slots_lock */
1870 int kvm_io_bus_write(struct kvm_io_bus *bus, gpa_t addr,
1871 		     int len, const void *val)
1872 {
1873 	int i;
1874 	for (i = 0; i < bus->dev_count; i++)
1875 		if (!kvm_iodevice_write(bus->devs[i], addr, len, val))
1876 			return 0;
1877 	return -EOPNOTSUPP;
1878 }
1879 
1880 /* kvm_io_bus_read - called under kvm->slots_lock */
1881 int kvm_io_bus_read(struct kvm_io_bus *bus, gpa_t addr, int len, void *val)
1882 {
1883 	int i;
1884 	for (i = 0; i < bus->dev_count; i++)
1885 		if (!kvm_iodevice_read(bus->devs[i], addr, len, val))
1886 			return 0;
1887 	return -EOPNOTSUPP;
1888 }
1889 
1890 int kvm_io_bus_register_dev(struct kvm *kvm, struct kvm_io_bus *bus,
1891 			     struct kvm_io_device *dev)
1892 {
1893 	int ret;
1894 
1895 	down_write(&kvm->slots_lock);
1896 	ret = __kvm_io_bus_register_dev(bus, dev);
1897 	up_write(&kvm->slots_lock);
1898 
1899 	return ret;
1900 }
1901 
1902 /* An unlocked version. Caller must have write lock on slots_lock. */
1903 int __kvm_io_bus_register_dev(struct kvm_io_bus *bus,
1904 			      struct kvm_io_device *dev)
1905 {
1906 	if (bus->dev_count > NR_IOBUS_DEVS-1)
1907 		return -ENOSPC;
1908 
1909 	bus->devs[bus->dev_count++] = dev;
1910 
1911 	return 0;
1912 }
1913 
1914 void kvm_io_bus_unregister_dev(struct kvm *kvm,
1915 			       struct kvm_io_bus *bus,
1916 			       struct kvm_io_device *dev)
1917 {
1918 	down_write(&kvm->slots_lock);
1919 	__kvm_io_bus_unregister_dev(bus, dev);
1920 	up_write(&kvm->slots_lock);
1921 }
1922 
1923 /* An unlocked version. Caller must have write lock on slots_lock. */
1924 void __kvm_io_bus_unregister_dev(struct kvm_io_bus *bus,
1925 				 struct kvm_io_device *dev)
1926 {
1927 	int i;
1928 
1929 	for (i = 0; i < bus->dev_count; i++)
1930 		if (bus->devs[i] == dev) {
1931 			bus->devs[i] = bus->devs[--bus->dev_count];
1932 			break;
1933 		}
1934 }
1935 
1936 static struct notifier_block kvm_cpu_notifier = {
1937 	.notifier_call = kvm_cpu_hotplug,
1938 	.priority = 20, /* must be > scheduler priority */
1939 };
1940 
1941 static int vm_stat_get(void *_offset, u64 *val)
1942 {
1943 	unsigned offset = (long)_offset;
1944 	struct kvm *kvm;
1945 
1946 	*val = 0;
1947 	spin_lock(&kvm_lock);
1948 	list_for_each_entry(kvm, &vm_list, vm_list)
1949 		*val += *(u32 *)((void *)kvm + offset);
1950 	spin_unlock(&kvm_lock);
1951 	return 0;
1952 }
1953 
1954 DEFINE_SIMPLE_ATTRIBUTE(vm_stat_fops, vm_stat_get, NULL, "%llu\n");
1955 
1956 static int vcpu_stat_get(void *_offset, u64 *val)
1957 {
1958 	unsigned offset = (long)_offset;
1959 	struct kvm *kvm;
1960 	struct kvm_vcpu *vcpu;
1961 	int i;
1962 
1963 	*val = 0;
1964 	spin_lock(&kvm_lock);
1965 	list_for_each_entry(kvm, &vm_list, vm_list)
1966 		kvm_for_each_vcpu(i, vcpu, kvm)
1967 			*val += *(u32 *)((void *)vcpu + offset);
1968 
1969 	spin_unlock(&kvm_lock);
1970 	return 0;
1971 }
1972 
1973 DEFINE_SIMPLE_ATTRIBUTE(vcpu_stat_fops, vcpu_stat_get, NULL, "%llu\n");
1974 
1975 static const struct file_operations *stat_fops[] = {
1976 	[KVM_STAT_VCPU] = &vcpu_stat_fops,
1977 	[KVM_STAT_VM]   = &vm_stat_fops,
1978 };
1979 
1980 static void kvm_init_debug(void)
1981 {
1982 	struct kvm_stats_debugfs_item *p;
1983 
1984 	kvm_debugfs_dir = debugfs_create_dir("kvm", NULL);
1985 	for (p = debugfs_entries; p->name; ++p)
1986 		p->dentry = debugfs_create_file(p->name, 0444, kvm_debugfs_dir,
1987 						(void *)(long)p->offset,
1988 						stat_fops[p->kind]);
1989 }
1990 
1991 static void kvm_exit_debug(void)
1992 {
1993 	struct kvm_stats_debugfs_item *p;
1994 
1995 	for (p = debugfs_entries; p->name; ++p)
1996 		debugfs_remove(p->dentry);
1997 	debugfs_remove(kvm_debugfs_dir);
1998 }
1999 
2000 static int kvm_suspend(struct sys_device *dev, pm_message_t state)
2001 {
2002 	if (kvm_usage_count)
2003 		hardware_disable(NULL);
2004 	return 0;
2005 }
2006 
2007 static int kvm_resume(struct sys_device *dev)
2008 {
2009 	if (kvm_usage_count)
2010 		hardware_enable(NULL);
2011 	return 0;
2012 }
2013 
2014 static struct sysdev_class kvm_sysdev_class = {
2015 	.name = "kvm",
2016 	.suspend = kvm_suspend,
2017 	.resume = kvm_resume,
2018 };
2019 
2020 static struct sys_device kvm_sysdev = {
2021 	.id = 0,
2022 	.cls = &kvm_sysdev_class,
2023 };
2024 
2025 struct page *bad_page;
2026 pfn_t bad_pfn;
2027 
2028 static inline
2029 struct kvm_vcpu *preempt_notifier_to_vcpu(struct preempt_notifier *pn)
2030 {
2031 	return container_of(pn, struct kvm_vcpu, preempt_notifier);
2032 }
2033 
2034 static void kvm_sched_in(struct preempt_notifier *pn, int cpu)
2035 {
2036 	struct kvm_vcpu *vcpu = preempt_notifier_to_vcpu(pn);
2037 
2038 	kvm_arch_vcpu_load(vcpu, cpu);
2039 }
2040 
2041 static void kvm_sched_out(struct preempt_notifier *pn,
2042 			  struct task_struct *next)
2043 {
2044 	struct kvm_vcpu *vcpu = preempt_notifier_to_vcpu(pn);
2045 
2046 	kvm_arch_vcpu_put(vcpu);
2047 }
2048 
2049 int kvm_init(void *opaque, unsigned int vcpu_size,
2050 		  struct module *module)
2051 {
2052 	int r;
2053 	int cpu;
2054 
2055 	r = kvm_arch_init(opaque);
2056 	if (r)
2057 		goto out_fail;
2058 
2059 	bad_page = alloc_page(GFP_KERNEL | __GFP_ZERO);
2060 
2061 	if (bad_page == NULL) {
2062 		r = -ENOMEM;
2063 		goto out;
2064 	}
2065 
2066 	bad_pfn = page_to_pfn(bad_page);
2067 
2068 	if (!zalloc_cpumask_var(&cpus_hardware_enabled, GFP_KERNEL)) {
2069 		r = -ENOMEM;
2070 		goto out_free_0;
2071 	}
2072 
2073 	r = kvm_arch_hardware_setup();
2074 	if (r < 0)
2075 		goto out_free_0a;
2076 
2077 	for_each_online_cpu(cpu) {
2078 		smp_call_function_single(cpu,
2079 				kvm_arch_check_processor_compat,
2080 				&r, 1);
2081 		if (r < 0)
2082 			goto out_free_1;
2083 	}
2084 
2085 	r = register_cpu_notifier(&kvm_cpu_notifier);
2086 	if (r)
2087 		goto out_free_2;
2088 	register_reboot_notifier(&kvm_reboot_notifier);
2089 
2090 	r = sysdev_class_register(&kvm_sysdev_class);
2091 	if (r)
2092 		goto out_free_3;
2093 
2094 	r = sysdev_register(&kvm_sysdev);
2095 	if (r)
2096 		goto out_free_4;
2097 
2098 	/* A kmem cache lets us meet the alignment requirements of fx_save. */
2099 	kvm_vcpu_cache = kmem_cache_create("kvm_vcpu", vcpu_size,
2100 					   __alignof__(struct kvm_vcpu),
2101 					   0, NULL);
2102 	if (!kvm_vcpu_cache) {
2103 		r = -ENOMEM;
2104 		goto out_free_5;
2105 	}
2106 
2107 	kvm_chardev_ops.owner = module;
2108 	kvm_vm_fops.owner = module;
2109 	kvm_vcpu_fops.owner = module;
2110 
2111 	r = misc_register(&kvm_dev);
2112 	if (r) {
2113 		printk(KERN_ERR "kvm: misc device register failed\n");
2114 		goto out_free;
2115 	}
2116 
2117 	kvm_preempt_ops.sched_in = kvm_sched_in;
2118 	kvm_preempt_ops.sched_out = kvm_sched_out;
2119 
2120 	kvm_init_debug();
2121 
2122 	return 0;
2123 
2124 out_free:
2125 	kmem_cache_destroy(kvm_vcpu_cache);
2126 out_free_5:
2127 	sysdev_unregister(&kvm_sysdev);
2128 out_free_4:
2129 	sysdev_class_unregister(&kvm_sysdev_class);
2130 out_free_3:
2131 	unregister_reboot_notifier(&kvm_reboot_notifier);
2132 	unregister_cpu_notifier(&kvm_cpu_notifier);
2133 out_free_2:
2134 out_free_1:
2135 	kvm_arch_hardware_unsetup();
2136 out_free_0a:
2137 	free_cpumask_var(cpus_hardware_enabled);
2138 out_free_0:
2139 	__free_page(bad_page);
2140 out:
2141 	kvm_arch_exit();
2142 out_fail:
2143 	return r;
2144 }
2145 EXPORT_SYMBOL_GPL(kvm_init);
2146 
2147 void kvm_exit(void)
2148 {
2149 	tracepoint_synchronize_unregister();
2150 	kvm_exit_debug();
2151 	misc_deregister(&kvm_dev);
2152 	kmem_cache_destroy(kvm_vcpu_cache);
2153 	sysdev_unregister(&kvm_sysdev);
2154 	sysdev_class_unregister(&kvm_sysdev_class);
2155 	unregister_reboot_notifier(&kvm_reboot_notifier);
2156 	unregister_cpu_notifier(&kvm_cpu_notifier);
2157 	on_each_cpu(hardware_disable, NULL, 1);
2158 	kvm_arch_hardware_unsetup();
2159 	kvm_arch_exit();
2160 	free_cpumask_var(cpus_hardware_enabled);
2161 	__free_page(bad_page);
2162 }
2163 EXPORT_SYMBOL_GPL(kvm_exit);
2164