xref: /openbmc/linux/virt/kvm/kvm_main.c (revision baa7eb025ab14f3cba2e35c0a8648f9c9f01d24f)
1 /*
2  * Kernel-based Virtual Machine driver for Linux
3  *
4  * This module enables machines with Intel VT-x extensions to run virtual
5  * machines without emulation or binary translation.
6  *
7  * Copyright (C) 2006 Qumranet, Inc.
8  * Copyright 2010 Red Hat, Inc. and/or its affiliates.
9  *
10  * Authors:
11  *   Avi Kivity   <avi@qumranet.com>
12  *   Yaniv Kamay  <yaniv@qumranet.com>
13  *
14  * This work is licensed under the terms of the GNU GPL, version 2.  See
15  * the COPYING file in the top-level directory.
16  *
17  */
18 
19 #include "iodev.h"
20 
21 #include <linux/kvm_host.h>
22 #include <linux/kvm.h>
23 #include <linux/module.h>
24 #include <linux/errno.h>
25 #include <linux/percpu.h>
26 #include <linux/mm.h>
27 #include <linux/miscdevice.h>
28 #include <linux/vmalloc.h>
29 #include <linux/reboot.h>
30 #include <linux/debugfs.h>
31 #include <linux/highmem.h>
32 #include <linux/file.h>
33 #include <linux/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 #include <linux/srcu.h>
48 #include <linux/hugetlb.h>
49 #include <linux/slab.h>
50 
51 #include <asm/processor.h>
52 #include <asm/io.h>
53 #include <asm/uaccess.h>
54 #include <asm/pgtable.h>
55 #include <asm-generic/bitops/le.h>
56 
57 #include "coalesced_mmio.h"
58 
59 #define CREATE_TRACE_POINTS
60 #include <trace/events/kvm.h>
61 
62 MODULE_AUTHOR("Qumranet");
63 MODULE_LICENSE("GPL");
64 
65 /*
66  * Ordering of locks:
67  *
68  * 		kvm->lock --> kvm->slots_lock --> kvm->irq_lock
69  */
70 
71 DEFINE_SPINLOCK(kvm_lock);
72 LIST_HEAD(vm_list);
73 
74 static cpumask_var_t cpus_hardware_enabled;
75 static int kvm_usage_count = 0;
76 static atomic_t hardware_enable_failed;
77 
78 struct kmem_cache *kvm_vcpu_cache;
79 EXPORT_SYMBOL_GPL(kvm_vcpu_cache);
80 
81 static __read_mostly struct preempt_ops kvm_preempt_ops;
82 
83 struct dentry *kvm_debugfs_dir;
84 
85 static long kvm_vcpu_ioctl(struct file *file, unsigned int ioctl,
86 			   unsigned long arg);
87 static int hardware_enable_all(void);
88 static void hardware_disable_all(void);
89 
90 static void kvm_io_bus_destroy(struct kvm_io_bus *bus);
91 
92 static bool kvm_rebooting;
93 
94 static bool largepages_enabled = true;
95 
96 static struct page *hwpoison_page;
97 static pfn_t hwpoison_pfn;
98 
99 static struct page *fault_page;
100 static pfn_t fault_pfn;
101 
102 inline int kvm_is_mmio_pfn(pfn_t pfn)
103 {
104 	if (pfn_valid(pfn)) {
105 		struct page *page = compound_head(pfn_to_page(pfn));
106 		return PageReserved(page);
107 	}
108 
109 	return true;
110 }
111 
112 /*
113  * Switches to specified vcpu, until a matching vcpu_put()
114  */
115 void vcpu_load(struct kvm_vcpu *vcpu)
116 {
117 	int cpu;
118 
119 	mutex_lock(&vcpu->mutex);
120 	cpu = get_cpu();
121 	preempt_notifier_register(&vcpu->preempt_notifier);
122 	kvm_arch_vcpu_load(vcpu, cpu);
123 	put_cpu();
124 }
125 
126 void vcpu_put(struct kvm_vcpu *vcpu)
127 {
128 	preempt_disable();
129 	kvm_arch_vcpu_put(vcpu);
130 	preempt_notifier_unregister(&vcpu->preempt_notifier);
131 	preempt_enable();
132 	mutex_unlock(&vcpu->mutex);
133 }
134 
135 static void ack_flush(void *_completed)
136 {
137 }
138 
139 static bool make_all_cpus_request(struct kvm *kvm, unsigned int req)
140 {
141 	int i, cpu, me;
142 	cpumask_var_t cpus;
143 	bool called = true;
144 	struct kvm_vcpu *vcpu;
145 
146 	zalloc_cpumask_var(&cpus, GFP_ATOMIC);
147 
148 	raw_spin_lock(&kvm->requests_lock);
149 	me = smp_processor_id();
150 	kvm_for_each_vcpu(i, vcpu, kvm) {
151 		if (kvm_make_check_request(req, vcpu))
152 			continue;
153 		cpu = vcpu->cpu;
154 		if (cpus != NULL && cpu != -1 && cpu != me)
155 			cpumask_set_cpu(cpu, cpus);
156 	}
157 	if (unlikely(cpus == NULL))
158 		smp_call_function_many(cpu_online_mask, ack_flush, NULL, 1);
159 	else if (!cpumask_empty(cpus))
160 		smp_call_function_many(cpus, ack_flush, NULL, 1);
161 	else
162 		called = false;
163 	raw_spin_unlock(&kvm->requests_lock);
164 	free_cpumask_var(cpus);
165 	return called;
166 }
167 
168 void kvm_flush_remote_tlbs(struct kvm *kvm)
169 {
170 	if (make_all_cpus_request(kvm, KVM_REQ_TLB_FLUSH))
171 		++kvm->stat.remote_tlb_flush;
172 }
173 
174 void kvm_reload_remote_mmus(struct kvm *kvm)
175 {
176 	make_all_cpus_request(kvm, KVM_REQ_MMU_RELOAD);
177 }
178 
179 int kvm_vcpu_init(struct kvm_vcpu *vcpu, struct kvm *kvm, unsigned id)
180 {
181 	struct page *page;
182 	int r;
183 
184 	mutex_init(&vcpu->mutex);
185 	vcpu->cpu = -1;
186 	vcpu->kvm = kvm;
187 	vcpu->vcpu_id = id;
188 	init_waitqueue_head(&vcpu->wq);
189 
190 	page = alloc_page(GFP_KERNEL | __GFP_ZERO);
191 	if (!page) {
192 		r = -ENOMEM;
193 		goto fail;
194 	}
195 	vcpu->run = page_address(page);
196 
197 	r = kvm_arch_vcpu_init(vcpu);
198 	if (r < 0)
199 		goto fail_free_run;
200 	return 0;
201 
202 fail_free_run:
203 	free_page((unsigned long)vcpu->run);
204 fail:
205 	return r;
206 }
207 EXPORT_SYMBOL_GPL(kvm_vcpu_init);
208 
209 void kvm_vcpu_uninit(struct kvm_vcpu *vcpu)
210 {
211 	kvm_arch_vcpu_uninit(vcpu);
212 	free_page((unsigned long)vcpu->run);
213 }
214 EXPORT_SYMBOL_GPL(kvm_vcpu_uninit);
215 
216 #if defined(CONFIG_MMU_NOTIFIER) && defined(KVM_ARCH_WANT_MMU_NOTIFIER)
217 static inline struct kvm *mmu_notifier_to_kvm(struct mmu_notifier *mn)
218 {
219 	return container_of(mn, struct kvm, mmu_notifier);
220 }
221 
222 static void kvm_mmu_notifier_invalidate_page(struct mmu_notifier *mn,
223 					     struct mm_struct *mm,
224 					     unsigned long address)
225 {
226 	struct kvm *kvm = mmu_notifier_to_kvm(mn);
227 	int need_tlb_flush, idx;
228 
229 	/*
230 	 * When ->invalidate_page runs, the linux pte has been zapped
231 	 * already but the page is still allocated until
232 	 * ->invalidate_page returns. So if we increase the sequence
233 	 * here the kvm page fault will notice if the spte can't be
234 	 * established because the page is going to be freed. If
235 	 * instead the kvm page fault establishes the spte before
236 	 * ->invalidate_page runs, kvm_unmap_hva will release it
237 	 * before returning.
238 	 *
239 	 * The sequence increase only need to be seen at spin_unlock
240 	 * time, and not at spin_lock time.
241 	 *
242 	 * Increasing the sequence after the spin_unlock would be
243 	 * unsafe because the kvm page fault could then establish the
244 	 * pte after kvm_unmap_hva returned, without noticing the page
245 	 * is going to be freed.
246 	 */
247 	idx = srcu_read_lock(&kvm->srcu);
248 	spin_lock(&kvm->mmu_lock);
249 	kvm->mmu_notifier_seq++;
250 	need_tlb_flush = kvm_unmap_hva(kvm, address);
251 	spin_unlock(&kvm->mmu_lock);
252 	srcu_read_unlock(&kvm->srcu, idx);
253 
254 	/* we've to flush the tlb before the pages can be freed */
255 	if (need_tlb_flush)
256 		kvm_flush_remote_tlbs(kvm);
257 
258 }
259 
260 static void kvm_mmu_notifier_change_pte(struct mmu_notifier *mn,
261 					struct mm_struct *mm,
262 					unsigned long address,
263 					pte_t pte)
264 {
265 	struct kvm *kvm = mmu_notifier_to_kvm(mn);
266 	int idx;
267 
268 	idx = srcu_read_lock(&kvm->srcu);
269 	spin_lock(&kvm->mmu_lock);
270 	kvm->mmu_notifier_seq++;
271 	kvm_set_spte_hva(kvm, address, pte);
272 	spin_unlock(&kvm->mmu_lock);
273 	srcu_read_unlock(&kvm->srcu, idx);
274 }
275 
276 static void kvm_mmu_notifier_invalidate_range_start(struct mmu_notifier *mn,
277 						    struct mm_struct *mm,
278 						    unsigned long start,
279 						    unsigned long end)
280 {
281 	struct kvm *kvm = mmu_notifier_to_kvm(mn);
282 	int need_tlb_flush = 0, idx;
283 
284 	idx = srcu_read_lock(&kvm->srcu);
285 	spin_lock(&kvm->mmu_lock);
286 	/*
287 	 * The count increase must become visible at unlock time as no
288 	 * spte can be established without taking the mmu_lock and
289 	 * count is also read inside the mmu_lock critical section.
290 	 */
291 	kvm->mmu_notifier_count++;
292 	for (; start < end; start += PAGE_SIZE)
293 		need_tlb_flush |= kvm_unmap_hva(kvm, start);
294 	spin_unlock(&kvm->mmu_lock);
295 	srcu_read_unlock(&kvm->srcu, idx);
296 
297 	/* we've to flush the tlb before the pages can be freed */
298 	if (need_tlb_flush)
299 		kvm_flush_remote_tlbs(kvm);
300 }
301 
302 static void kvm_mmu_notifier_invalidate_range_end(struct mmu_notifier *mn,
303 						  struct mm_struct *mm,
304 						  unsigned long start,
305 						  unsigned long end)
306 {
307 	struct kvm *kvm = mmu_notifier_to_kvm(mn);
308 
309 	spin_lock(&kvm->mmu_lock);
310 	/*
311 	 * This sequence increase will notify the kvm page fault that
312 	 * the page that is going to be mapped in the spte could have
313 	 * been freed.
314 	 */
315 	kvm->mmu_notifier_seq++;
316 	/*
317 	 * The above sequence increase must be visible before the
318 	 * below count decrease but both values are read by the kvm
319 	 * page fault under mmu_lock spinlock so we don't need to add
320 	 * a smb_wmb() here in between the two.
321 	 */
322 	kvm->mmu_notifier_count--;
323 	spin_unlock(&kvm->mmu_lock);
324 
325 	BUG_ON(kvm->mmu_notifier_count < 0);
326 }
327 
328 static int kvm_mmu_notifier_clear_flush_young(struct mmu_notifier *mn,
329 					      struct mm_struct *mm,
330 					      unsigned long address)
331 {
332 	struct kvm *kvm = mmu_notifier_to_kvm(mn);
333 	int young, idx;
334 
335 	idx = srcu_read_lock(&kvm->srcu);
336 	spin_lock(&kvm->mmu_lock);
337 	young = kvm_age_hva(kvm, address);
338 	spin_unlock(&kvm->mmu_lock);
339 	srcu_read_unlock(&kvm->srcu, idx);
340 
341 	if (young)
342 		kvm_flush_remote_tlbs(kvm);
343 
344 	return young;
345 }
346 
347 static void kvm_mmu_notifier_release(struct mmu_notifier *mn,
348 				     struct mm_struct *mm)
349 {
350 	struct kvm *kvm = mmu_notifier_to_kvm(mn);
351 	int idx;
352 
353 	idx = srcu_read_lock(&kvm->srcu);
354 	kvm_arch_flush_shadow(kvm);
355 	srcu_read_unlock(&kvm->srcu, idx);
356 }
357 
358 static const struct mmu_notifier_ops kvm_mmu_notifier_ops = {
359 	.invalidate_page	= kvm_mmu_notifier_invalidate_page,
360 	.invalidate_range_start	= kvm_mmu_notifier_invalidate_range_start,
361 	.invalidate_range_end	= kvm_mmu_notifier_invalidate_range_end,
362 	.clear_flush_young	= kvm_mmu_notifier_clear_flush_young,
363 	.change_pte		= kvm_mmu_notifier_change_pte,
364 	.release		= kvm_mmu_notifier_release,
365 };
366 
367 static int kvm_init_mmu_notifier(struct kvm *kvm)
368 {
369 	kvm->mmu_notifier.ops = &kvm_mmu_notifier_ops;
370 	return mmu_notifier_register(&kvm->mmu_notifier, current->mm);
371 }
372 
373 #else  /* !(CONFIG_MMU_NOTIFIER && KVM_ARCH_WANT_MMU_NOTIFIER) */
374 
375 static int kvm_init_mmu_notifier(struct kvm *kvm)
376 {
377 	return 0;
378 }
379 
380 #endif /* CONFIG_MMU_NOTIFIER && KVM_ARCH_WANT_MMU_NOTIFIER */
381 
382 static struct kvm *kvm_create_vm(void)
383 {
384 	int r = 0, i;
385 	struct kvm *kvm = kvm_arch_create_vm();
386 
387 	if (IS_ERR(kvm))
388 		goto out;
389 
390 	r = hardware_enable_all();
391 	if (r)
392 		goto out_err_nodisable;
393 
394 #ifdef CONFIG_HAVE_KVM_IRQCHIP
395 	INIT_HLIST_HEAD(&kvm->mask_notifier_list);
396 	INIT_HLIST_HEAD(&kvm->irq_ack_notifier_list);
397 #endif
398 
399 	r = -ENOMEM;
400 	kvm->memslots = kzalloc(sizeof(struct kvm_memslots), GFP_KERNEL);
401 	if (!kvm->memslots)
402 		goto out_err;
403 	if (init_srcu_struct(&kvm->srcu))
404 		goto out_err;
405 	for (i = 0; i < KVM_NR_BUSES; i++) {
406 		kvm->buses[i] = kzalloc(sizeof(struct kvm_io_bus),
407 					GFP_KERNEL);
408 		if (!kvm->buses[i]) {
409 			cleanup_srcu_struct(&kvm->srcu);
410 			goto out_err;
411 		}
412 	}
413 
414 	r = kvm_init_mmu_notifier(kvm);
415 	if (r) {
416 		cleanup_srcu_struct(&kvm->srcu);
417 		goto out_err;
418 	}
419 
420 	kvm->mm = current->mm;
421 	atomic_inc(&kvm->mm->mm_count);
422 	spin_lock_init(&kvm->mmu_lock);
423 	raw_spin_lock_init(&kvm->requests_lock);
424 	kvm_eventfd_init(kvm);
425 	mutex_init(&kvm->lock);
426 	mutex_init(&kvm->irq_lock);
427 	mutex_init(&kvm->slots_lock);
428 	atomic_set(&kvm->users_count, 1);
429 	spin_lock(&kvm_lock);
430 	list_add(&kvm->vm_list, &vm_list);
431 	spin_unlock(&kvm_lock);
432 out:
433 	return kvm;
434 
435 out_err:
436 	hardware_disable_all();
437 out_err_nodisable:
438 	for (i = 0; i < KVM_NR_BUSES; i++)
439 		kfree(kvm->buses[i]);
440 	kfree(kvm->memslots);
441 	kfree(kvm);
442 	return ERR_PTR(r);
443 }
444 
445 /*
446  * Free any memory in @free but not in @dont.
447  */
448 static void kvm_free_physmem_slot(struct kvm_memory_slot *free,
449 				  struct kvm_memory_slot *dont)
450 {
451 	int i;
452 
453 	if (!dont || free->rmap != dont->rmap)
454 		vfree(free->rmap);
455 
456 	if (!dont || free->dirty_bitmap != dont->dirty_bitmap)
457 		vfree(free->dirty_bitmap);
458 
459 
460 	for (i = 0; i < KVM_NR_PAGE_SIZES - 1; ++i) {
461 		if (!dont || free->lpage_info[i] != dont->lpage_info[i]) {
462 			vfree(free->lpage_info[i]);
463 			free->lpage_info[i] = NULL;
464 		}
465 	}
466 
467 	free->npages = 0;
468 	free->dirty_bitmap = NULL;
469 	free->rmap = NULL;
470 }
471 
472 void kvm_free_physmem(struct kvm *kvm)
473 {
474 	int i;
475 	struct kvm_memslots *slots = kvm->memslots;
476 
477 	for (i = 0; i < slots->nmemslots; ++i)
478 		kvm_free_physmem_slot(&slots->memslots[i], NULL);
479 
480 	kfree(kvm->memslots);
481 }
482 
483 static void kvm_destroy_vm(struct kvm *kvm)
484 {
485 	int i;
486 	struct mm_struct *mm = kvm->mm;
487 
488 	kvm_arch_sync_events(kvm);
489 	spin_lock(&kvm_lock);
490 	list_del(&kvm->vm_list);
491 	spin_unlock(&kvm_lock);
492 	kvm_free_irq_routing(kvm);
493 	for (i = 0; i < KVM_NR_BUSES; i++)
494 		kvm_io_bus_destroy(kvm->buses[i]);
495 	kvm_coalesced_mmio_free(kvm);
496 #if defined(CONFIG_MMU_NOTIFIER) && defined(KVM_ARCH_WANT_MMU_NOTIFIER)
497 	mmu_notifier_unregister(&kvm->mmu_notifier, kvm->mm);
498 #else
499 	kvm_arch_flush_shadow(kvm);
500 #endif
501 	kvm_arch_destroy_vm(kvm);
502 	hardware_disable_all();
503 	mmdrop(mm);
504 }
505 
506 void kvm_get_kvm(struct kvm *kvm)
507 {
508 	atomic_inc(&kvm->users_count);
509 }
510 EXPORT_SYMBOL_GPL(kvm_get_kvm);
511 
512 void kvm_put_kvm(struct kvm *kvm)
513 {
514 	if (atomic_dec_and_test(&kvm->users_count))
515 		kvm_destroy_vm(kvm);
516 }
517 EXPORT_SYMBOL_GPL(kvm_put_kvm);
518 
519 
520 static int kvm_vm_release(struct inode *inode, struct file *filp)
521 {
522 	struct kvm *kvm = filp->private_data;
523 
524 	kvm_irqfd_release(kvm);
525 
526 	kvm_put_kvm(kvm);
527 	return 0;
528 }
529 
530 /*
531  * Allocate some memory and give it an address in the guest physical address
532  * space.
533  *
534  * Discontiguous memory is allowed, mostly for framebuffers.
535  *
536  * Must be called holding mmap_sem for write.
537  */
538 int __kvm_set_memory_region(struct kvm *kvm,
539 			    struct kvm_userspace_memory_region *mem,
540 			    int user_alloc)
541 {
542 	int r, flush_shadow = 0;
543 	gfn_t base_gfn;
544 	unsigned long npages;
545 	unsigned long i;
546 	struct kvm_memory_slot *memslot;
547 	struct kvm_memory_slot old, new;
548 	struct kvm_memslots *slots, *old_memslots;
549 
550 	r = -EINVAL;
551 	/* General sanity checks */
552 	if (mem->memory_size & (PAGE_SIZE - 1))
553 		goto out;
554 	if (mem->guest_phys_addr & (PAGE_SIZE - 1))
555 		goto out;
556 	if (user_alloc && (mem->userspace_addr & (PAGE_SIZE - 1)))
557 		goto out;
558 	if (mem->slot >= KVM_MEMORY_SLOTS + KVM_PRIVATE_MEM_SLOTS)
559 		goto out;
560 	if (mem->guest_phys_addr + mem->memory_size < mem->guest_phys_addr)
561 		goto out;
562 
563 	memslot = &kvm->memslots->memslots[mem->slot];
564 	base_gfn = mem->guest_phys_addr >> PAGE_SHIFT;
565 	npages = mem->memory_size >> PAGE_SHIFT;
566 
567 	r = -EINVAL;
568 	if (npages > KVM_MEM_MAX_NR_PAGES)
569 		goto out;
570 
571 	if (!npages)
572 		mem->flags &= ~KVM_MEM_LOG_DIRTY_PAGES;
573 
574 	new = old = *memslot;
575 
576 	new.id = mem->slot;
577 	new.base_gfn = base_gfn;
578 	new.npages = npages;
579 	new.flags = mem->flags;
580 
581 	/* Disallow changing a memory slot's size. */
582 	r = -EINVAL;
583 	if (npages && old.npages && npages != old.npages)
584 		goto out_free;
585 
586 	/* Check for overlaps */
587 	r = -EEXIST;
588 	for (i = 0; i < KVM_MEMORY_SLOTS; ++i) {
589 		struct kvm_memory_slot *s = &kvm->memslots->memslots[i];
590 
591 		if (s == memslot || !s->npages)
592 			continue;
593 		if (!((base_gfn + npages <= s->base_gfn) ||
594 		      (base_gfn >= s->base_gfn + s->npages)))
595 			goto out_free;
596 	}
597 
598 	/* Free page dirty bitmap if unneeded */
599 	if (!(new.flags & KVM_MEM_LOG_DIRTY_PAGES))
600 		new.dirty_bitmap = NULL;
601 
602 	r = -ENOMEM;
603 
604 	/* Allocate if a slot is being created */
605 #ifndef CONFIG_S390
606 	if (npages && !new.rmap) {
607 		new.rmap = vmalloc(npages * sizeof(*new.rmap));
608 
609 		if (!new.rmap)
610 			goto out_free;
611 
612 		memset(new.rmap, 0, npages * sizeof(*new.rmap));
613 
614 		new.user_alloc = user_alloc;
615 		new.userspace_addr = mem->userspace_addr;
616 	}
617 	if (!npages)
618 		goto skip_lpage;
619 
620 	for (i = 0; i < KVM_NR_PAGE_SIZES - 1; ++i) {
621 		unsigned long ugfn;
622 		unsigned long j;
623 		int lpages;
624 		int level = i + 2;
625 
626 		/* Avoid unused variable warning if no large pages */
627 		(void)level;
628 
629 		if (new.lpage_info[i])
630 			continue;
631 
632 		lpages = 1 + ((base_gfn + npages - 1)
633 			     >> KVM_HPAGE_GFN_SHIFT(level));
634 		lpages -= base_gfn >> KVM_HPAGE_GFN_SHIFT(level);
635 
636 		new.lpage_info[i] = vmalloc(lpages * sizeof(*new.lpage_info[i]));
637 
638 		if (!new.lpage_info[i])
639 			goto out_free;
640 
641 		memset(new.lpage_info[i], 0,
642 		       lpages * sizeof(*new.lpage_info[i]));
643 
644 		if (base_gfn & (KVM_PAGES_PER_HPAGE(level) - 1))
645 			new.lpage_info[i][0].write_count = 1;
646 		if ((base_gfn+npages) & (KVM_PAGES_PER_HPAGE(level) - 1))
647 			new.lpage_info[i][lpages - 1].write_count = 1;
648 		ugfn = new.userspace_addr >> PAGE_SHIFT;
649 		/*
650 		 * If the gfn and userspace address are not aligned wrt each
651 		 * other, or if explicitly asked to, disable large page
652 		 * support for this slot
653 		 */
654 		if ((base_gfn ^ ugfn) & (KVM_PAGES_PER_HPAGE(level) - 1) ||
655 		    !largepages_enabled)
656 			for (j = 0; j < lpages; ++j)
657 				new.lpage_info[i][j].write_count = 1;
658 	}
659 
660 skip_lpage:
661 
662 	/* Allocate page dirty bitmap if needed */
663 	if ((new.flags & KVM_MEM_LOG_DIRTY_PAGES) && !new.dirty_bitmap) {
664 		unsigned long dirty_bytes = kvm_dirty_bitmap_bytes(&new);
665 
666 		new.dirty_bitmap = vmalloc(dirty_bytes);
667 		if (!new.dirty_bitmap)
668 			goto out_free;
669 		memset(new.dirty_bitmap, 0, dirty_bytes);
670 		/* destroy any largepage mappings for dirty tracking */
671 		if (old.npages)
672 			flush_shadow = 1;
673 	}
674 #else  /* not defined CONFIG_S390 */
675 	new.user_alloc = user_alloc;
676 	if (user_alloc)
677 		new.userspace_addr = mem->userspace_addr;
678 #endif /* not defined CONFIG_S390 */
679 
680 	if (!npages) {
681 		r = -ENOMEM;
682 		slots = kzalloc(sizeof(struct kvm_memslots), GFP_KERNEL);
683 		if (!slots)
684 			goto out_free;
685 		memcpy(slots, kvm->memslots, sizeof(struct kvm_memslots));
686 		if (mem->slot >= slots->nmemslots)
687 			slots->nmemslots = mem->slot + 1;
688 		slots->memslots[mem->slot].flags |= KVM_MEMSLOT_INVALID;
689 
690 		old_memslots = kvm->memslots;
691 		rcu_assign_pointer(kvm->memslots, slots);
692 		synchronize_srcu_expedited(&kvm->srcu);
693 		/* From this point no new shadow pages pointing to a deleted
694 		 * memslot will be created.
695 		 *
696 		 * validation of sp->gfn happens in:
697 		 * 	- gfn_to_hva (kvm_read_guest, gfn_to_pfn)
698 		 * 	- kvm_is_visible_gfn (mmu_check_roots)
699 		 */
700 		kvm_arch_flush_shadow(kvm);
701 		kfree(old_memslots);
702 	}
703 
704 	r = kvm_arch_prepare_memory_region(kvm, &new, old, mem, user_alloc);
705 	if (r)
706 		goto out_free;
707 
708 	/* map the pages in iommu page table */
709 	if (npages) {
710 		r = kvm_iommu_map_pages(kvm, &new);
711 		if (r)
712 			goto out_free;
713 	}
714 
715 	r = -ENOMEM;
716 	slots = kzalloc(sizeof(struct kvm_memslots), GFP_KERNEL);
717 	if (!slots)
718 		goto out_free;
719 	memcpy(slots, kvm->memslots, sizeof(struct kvm_memslots));
720 	if (mem->slot >= slots->nmemslots)
721 		slots->nmemslots = mem->slot + 1;
722 
723 	/* actual memory is freed via old in kvm_free_physmem_slot below */
724 	if (!npages) {
725 		new.rmap = NULL;
726 		new.dirty_bitmap = NULL;
727 		for (i = 0; i < KVM_NR_PAGE_SIZES - 1; ++i)
728 			new.lpage_info[i] = NULL;
729 	}
730 
731 	slots->memslots[mem->slot] = new;
732 	old_memslots = kvm->memslots;
733 	rcu_assign_pointer(kvm->memslots, slots);
734 	synchronize_srcu_expedited(&kvm->srcu);
735 
736 	kvm_arch_commit_memory_region(kvm, mem, old, user_alloc);
737 
738 	kvm_free_physmem_slot(&old, &new);
739 	kfree(old_memslots);
740 
741 	if (flush_shadow)
742 		kvm_arch_flush_shadow(kvm);
743 
744 	return 0;
745 
746 out_free:
747 	kvm_free_physmem_slot(&new, &old);
748 out:
749 	return r;
750 
751 }
752 EXPORT_SYMBOL_GPL(__kvm_set_memory_region);
753 
754 int kvm_set_memory_region(struct kvm *kvm,
755 			  struct kvm_userspace_memory_region *mem,
756 			  int user_alloc)
757 {
758 	int r;
759 
760 	mutex_lock(&kvm->slots_lock);
761 	r = __kvm_set_memory_region(kvm, mem, user_alloc);
762 	mutex_unlock(&kvm->slots_lock);
763 	return r;
764 }
765 EXPORT_SYMBOL_GPL(kvm_set_memory_region);
766 
767 int kvm_vm_ioctl_set_memory_region(struct kvm *kvm,
768 				   struct
769 				   kvm_userspace_memory_region *mem,
770 				   int user_alloc)
771 {
772 	if (mem->slot >= KVM_MEMORY_SLOTS)
773 		return -EINVAL;
774 	return kvm_set_memory_region(kvm, mem, user_alloc);
775 }
776 
777 int kvm_get_dirty_log(struct kvm *kvm,
778 			struct kvm_dirty_log *log, int *is_dirty)
779 {
780 	struct kvm_memory_slot *memslot;
781 	int r, i;
782 	unsigned long n;
783 	unsigned long any = 0;
784 
785 	r = -EINVAL;
786 	if (log->slot >= KVM_MEMORY_SLOTS)
787 		goto out;
788 
789 	memslot = &kvm->memslots->memslots[log->slot];
790 	r = -ENOENT;
791 	if (!memslot->dirty_bitmap)
792 		goto out;
793 
794 	n = kvm_dirty_bitmap_bytes(memslot);
795 
796 	for (i = 0; !any && i < n/sizeof(long); ++i)
797 		any = memslot->dirty_bitmap[i];
798 
799 	r = -EFAULT;
800 	if (copy_to_user(log->dirty_bitmap, memslot->dirty_bitmap, n))
801 		goto out;
802 
803 	if (any)
804 		*is_dirty = 1;
805 
806 	r = 0;
807 out:
808 	return r;
809 }
810 
811 void kvm_disable_largepages(void)
812 {
813 	largepages_enabled = false;
814 }
815 EXPORT_SYMBOL_GPL(kvm_disable_largepages);
816 
817 int is_error_page(struct page *page)
818 {
819 	return page == bad_page || page == hwpoison_page || page == fault_page;
820 }
821 EXPORT_SYMBOL_GPL(is_error_page);
822 
823 int is_error_pfn(pfn_t pfn)
824 {
825 	return pfn == bad_pfn || pfn == hwpoison_pfn || pfn == fault_pfn;
826 }
827 EXPORT_SYMBOL_GPL(is_error_pfn);
828 
829 int is_hwpoison_pfn(pfn_t pfn)
830 {
831 	return pfn == hwpoison_pfn;
832 }
833 EXPORT_SYMBOL_GPL(is_hwpoison_pfn);
834 
835 int is_fault_pfn(pfn_t pfn)
836 {
837 	return pfn == fault_pfn;
838 }
839 EXPORT_SYMBOL_GPL(is_fault_pfn);
840 
841 static inline unsigned long bad_hva(void)
842 {
843 	return PAGE_OFFSET;
844 }
845 
846 int kvm_is_error_hva(unsigned long addr)
847 {
848 	return addr == bad_hva();
849 }
850 EXPORT_SYMBOL_GPL(kvm_is_error_hva);
851 
852 struct kvm_memory_slot *gfn_to_memslot(struct kvm *kvm, gfn_t gfn)
853 {
854 	int i;
855 	struct kvm_memslots *slots = kvm_memslots(kvm);
856 
857 	for (i = 0; i < slots->nmemslots; ++i) {
858 		struct kvm_memory_slot *memslot = &slots->memslots[i];
859 
860 		if (gfn >= memslot->base_gfn
861 		    && gfn < memslot->base_gfn + memslot->npages)
862 			return memslot;
863 	}
864 	return NULL;
865 }
866 EXPORT_SYMBOL_GPL(gfn_to_memslot);
867 
868 int kvm_is_visible_gfn(struct kvm *kvm, gfn_t gfn)
869 {
870 	int i;
871 	struct kvm_memslots *slots = kvm_memslots(kvm);
872 
873 	for (i = 0; i < KVM_MEMORY_SLOTS; ++i) {
874 		struct kvm_memory_slot *memslot = &slots->memslots[i];
875 
876 		if (memslot->flags & KVM_MEMSLOT_INVALID)
877 			continue;
878 
879 		if (gfn >= memslot->base_gfn
880 		    && gfn < memslot->base_gfn + memslot->npages)
881 			return 1;
882 	}
883 	return 0;
884 }
885 EXPORT_SYMBOL_GPL(kvm_is_visible_gfn);
886 
887 unsigned long kvm_host_page_size(struct kvm *kvm, gfn_t gfn)
888 {
889 	struct vm_area_struct *vma;
890 	unsigned long addr, size;
891 
892 	size = PAGE_SIZE;
893 
894 	addr = gfn_to_hva(kvm, gfn);
895 	if (kvm_is_error_hva(addr))
896 		return PAGE_SIZE;
897 
898 	down_read(&current->mm->mmap_sem);
899 	vma = find_vma(current->mm, addr);
900 	if (!vma)
901 		goto out;
902 
903 	size = vma_kernel_pagesize(vma);
904 
905 out:
906 	up_read(&current->mm->mmap_sem);
907 
908 	return size;
909 }
910 
911 int memslot_id(struct kvm *kvm, gfn_t gfn)
912 {
913 	int i;
914 	struct kvm_memslots *slots = kvm_memslots(kvm);
915 	struct kvm_memory_slot *memslot = NULL;
916 
917 	for (i = 0; i < slots->nmemslots; ++i) {
918 		memslot = &slots->memslots[i];
919 
920 		if (gfn >= memslot->base_gfn
921 		    && gfn < memslot->base_gfn + memslot->npages)
922 			break;
923 	}
924 
925 	return memslot - slots->memslots;
926 }
927 
928 static unsigned long gfn_to_hva_many(struct kvm *kvm, gfn_t gfn,
929 				     gfn_t *nr_pages)
930 {
931 	struct kvm_memory_slot *slot;
932 
933 	slot = gfn_to_memslot(kvm, gfn);
934 	if (!slot || slot->flags & KVM_MEMSLOT_INVALID)
935 		return bad_hva();
936 
937 	if (nr_pages)
938 		*nr_pages = slot->npages - (gfn - slot->base_gfn);
939 
940 	return gfn_to_hva_memslot(slot, gfn);
941 }
942 
943 unsigned long gfn_to_hva(struct kvm *kvm, gfn_t gfn)
944 {
945 	return gfn_to_hva_many(kvm, gfn, NULL);
946 }
947 EXPORT_SYMBOL_GPL(gfn_to_hva);
948 
949 static pfn_t hva_to_pfn(struct kvm *kvm, unsigned long addr, bool atomic)
950 {
951 	struct page *page[1];
952 	int npages;
953 	pfn_t pfn;
954 
955 	if (atomic)
956 		npages = __get_user_pages_fast(addr, 1, 1, page);
957 	else {
958 		might_sleep();
959 		npages = get_user_pages_fast(addr, 1, 1, page);
960 	}
961 
962 	if (unlikely(npages != 1)) {
963 		struct vm_area_struct *vma;
964 
965 		if (atomic)
966 			goto return_fault_page;
967 
968 		down_read(&current->mm->mmap_sem);
969 		if (is_hwpoison_address(addr)) {
970 			up_read(&current->mm->mmap_sem);
971 			get_page(hwpoison_page);
972 			return page_to_pfn(hwpoison_page);
973 		}
974 
975 		vma = find_vma(current->mm, addr);
976 
977 		if (vma == NULL || addr < vma->vm_start ||
978 		    !(vma->vm_flags & VM_PFNMAP)) {
979 			up_read(&current->mm->mmap_sem);
980 return_fault_page:
981 			get_page(fault_page);
982 			return page_to_pfn(fault_page);
983 		}
984 
985 		pfn = ((addr - vma->vm_start) >> PAGE_SHIFT) + vma->vm_pgoff;
986 		up_read(&current->mm->mmap_sem);
987 		BUG_ON(!kvm_is_mmio_pfn(pfn));
988 	} else
989 		pfn = page_to_pfn(page[0]);
990 
991 	return pfn;
992 }
993 
994 pfn_t hva_to_pfn_atomic(struct kvm *kvm, unsigned long addr)
995 {
996 	return hva_to_pfn(kvm, addr, true);
997 }
998 EXPORT_SYMBOL_GPL(hva_to_pfn_atomic);
999 
1000 static pfn_t __gfn_to_pfn(struct kvm *kvm, gfn_t gfn, bool atomic)
1001 {
1002 	unsigned long addr;
1003 
1004 	addr = gfn_to_hva(kvm, gfn);
1005 	if (kvm_is_error_hva(addr)) {
1006 		get_page(bad_page);
1007 		return page_to_pfn(bad_page);
1008 	}
1009 
1010 	return hva_to_pfn(kvm, addr, atomic);
1011 }
1012 
1013 pfn_t gfn_to_pfn_atomic(struct kvm *kvm, gfn_t gfn)
1014 {
1015 	return __gfn_to_pfn(kvm, gfn, true);
1016 }
1017 EXPORT_SYMBOL_GPL(gfn_to_pfn_atomic);
1018 
1019 pfn_t gfn_to_pfn(struct kvm *kvm, gfn_t gfn)
1020 {
1021 	return __gfn_to_pfn(kvm, gfn, false);
1022 }
1023 EXPORT_SYMBOL_GPL(gfn_to_pfn);
1024 
1025 pfn_t gfn_to_pfn_memslot(struct kvm *kvm,
1026 			 struct kvm_memory_slot *slot, gfn_t gfn)
1027 {
1028 	unsigned long addr = gfn_to_hva_memslot(slot, gfn);
1029 	return hva_to_pfn(kvm, addr, false);
1030 }
1031 
1032 int gfn_to_page_many_atomic(struct kvm *kvm, gfn_t gfn, struct page **pages,
1033 								  int nr_pages)
1034 {
1035 	unsigned long addr;
1036 	gfn_t entry;
1037 
1038 	addr = gfn_to_hva_many(kvm, gfn, &entry);
1039 	if (kvm_is_error_hva(addr))
1040 		return -1;
1041 
1042 	if (entry < nr_pages)
1043 		return 0;
1044 
1045 	return __get_user_pages_fast(addr, nr_pages, 1, pages);
1046 }
1047 EXPORT_SYMBOL_GPL(gfn_to_page_many_atomic);
1048 
1049 struct page *gfn_to_page(struct kvm *kvm, gfn_t gfn)
1050 {
1051 	pfn_t pfn;
1052 
1053 	pfn = gfn_to_pfn(kvm, gfn);
1054 	if (!kvm_is_mmio_pfn(pfn))
1055 		return pfn_to_page(pfn);
1056 
1057 	WARN_ON(kvm_is_mmio_pfn(pfn));
1058 
1059 	get_page(bad_page);
1060 	return bad_page;
1061 }
1062 
1063 EXPORT_SYMBOL_GPL(gfn_to_page);
1064 
1065 void kvm_release_page_clean(struct page *page)
1066 {
1067 	kvm_release_pfn_clean(page_to_pfn(page));
1068 }
1069 EXPORT_SYMBOL_GPL(kvm_release_page_clean);
1070 
1071 void kvm_release_pfn_clean(pfn_t pfn)
1072 {
1073 	if (!kvm_is_mmio_pfn(pfn))
1074 		put_page(pfn_to_page(pfn));
1075 }
1076 EXPORT_SYMBOL_GPL(kvm_release_pfn_clean);
1077 
1078 void kvm_release_page_dirty(struct page *page)
1079 {
1080 	kvm_release_pfn_dirty(page_to_pfn(page));
1081 }
1082 EXPORT_SYMBOL_GPL(kvm_release_page_dirty);
1083 
1084 void kvm_release_pfn_dirty(pfn_t pfn)
1085 {
1086 	kvm_set_pfn_dirty(pfn);
1087 	kvm_release_pfn_clean(pfn);
1088 }
1089 EXPORT_SYMBOL_GPL(kvm_release_pfn_dirty);
1090 
1091 void kvm_set_page_dirty(struct page *page)
1092 {
1093 	kvm_set_pfn_dirty(page_to_pfn(page));
1094 }
1095 EXPORT_SYMBOL_GPL(kvm_set_page_dirty);
1096 
1097 void kvm_set_pfn_dirty(pfn_t pfn)
1098 {
1099 	if (!kvm_is_mmio_pfn(pfn)) {
1100 		struct page *page = pfn_to_page(pfn);
1101 		if (!PageReserved(page))
1102 			SetPageDirty(page);
1103 	}
1104 }
1105 EXPORT_SYMBOL_GPL(kvm_set_pfn_dirty);
1106 
1107 void kvm_set_pfn_accessed(pfn_t pfn)
1108 {
1109 	if (!kvm_is_mmio_pfn(pfn))
1110 		mark_page_accessed(pfn_to_page(pfn));
1111 }
1112 EXPORT_SYMBOL_GPL(kvm_set_pfn_accessed);
1113 
1114 void kvm_get_pfn(pfn_t pfn)
1115 {
1116 	if (!kvm_is_mmio_pfn(pfn))
1117 		get_page(pfn_to_page(pfn));
1118 }
1119 EXPORT_SYMBOL_GPL(kvm_get_pfn);
1120 
1121 static int next_segment(unsigned long len, int offset)
1122 {
1123 	if (len > PAGE_SIZE - offset)
1124 		return PAGE_SIZE - offset;
1125 	else
1126 		return len;
1127 }
1128 
1129 int kvm_read_guest_page(struct kvm *kvm, gfn_t gfn, void *data, int offset,
1130 			int len)
1131 {
1132 	int r;
1133 	unsigned long addr;
1134 
1135 	addr = gfn_to_hva(kvm, gfn);
1136 	if (kvm_is_error_hva(addr))
1137 		return -EFAULT;
1138 	r = copy_from_user(data, (void __user *)addr + offset, len);
1139 	if (r)
1140 		return -EFAULT;
1141 	return 0;
1142 }
1143 EXPORT_SYMBOL_GPL(kvm_read_guest_page);
1144 
1145 int kvm_read_guest(struct kvm *kvm, gpa_t gpa, void *data, unsigned long len)
1146 {
1147 	gfn_t gfn = gpa >> PAGE_SHIFT;
1148 	int seg;
1149 	int offset = offset_in_page(gpa);
1150 	int ret;
1151 
1152 	while ((seg = next_segment(len, offset)) != 0) {
1153 		ret = kvm_read_guest_page(kvm, gfn, data, offset, seg);
1154 		if (ret < 0)
1155 			return ret;
1156 		offset = 0;
1157 		len -= seg;
1158 		data += seg;
1159 		++gfn;
1160 	}
1161 	return 0;
1162 }
1163 EXPORT_SYMBOL_GPL(kvm_read_guest);
1164 
1165 int kvm_read_guest_atomic(struct kvm *kvm, gpa_t gpa, void *data,
1166 			  unsigned long len)
1167 {
1168 	int r;
1169 	unsigned long addr;
1170 	gfn_t gfn = gpa >> PAGE_SHIFT;
1171 	int offset = offset_in_page(gpa);
1172 
1173 	addr = gfn_to_hva(kvm, gfn);
1174 	if (kvm_is_error_hva(addr))
1175 		return -EFAULT;
1176 	pagefault_disable();
1177 	r = __copy_from_user_inatomic(data, (void __user *)addr + offset, len);
1178 	pagefault_enable();
1179 	if (r)
1180 		return -EFAULT;
1181 	return 0;
1182 }
1183 EXPORT_SYMBOL(kvm_read_guest_atomic);
1184 
1185 int kvm_write_guest_page(struct kvm *kvm, gfn_t gfn, const void *data,
1186 			 int offset, int len)
1187 {
1188 	int r;
1189 	unsigned long addr;
1190 
1191 	addr = gfn_to_hva(kvm, gfn);
1192 	if (kvm_is_error_hva(addr))
1193 		return -EFAULT;
1194 	r = copy_to_user((void __user *)addr + offset, data, len);
1195 	if (r)
1196 		return -EFAULT;
1197 	mark_page_dirty(kvm, gfn);
1198 	return 0;
1199 }
1200 EXPORT_SYMBOL_GPL(kvm_write_guest_page);
1201 
1202 int kvm_write_guest(struct kvm *kvm, gpa_t gpa, const void *data,
1203 		    unsigned long len)
1204 {
1205 	gfn_t gfn = gpa >> PAGE_SHIFT;
1206 	int seg;
1207 	int offset = offset_in_page(gpa);
1208 	int ret;
1209 
1210 	while ((seg = next_segment(len, offset)) != 0) {
1211 		ret = kvm_write_guest_page(kvm, gfn, data, offset, seg);
1212 		if (ret < 0)
1213 			return ret;
1214 		offset = 0;
1215 		len -= seg;
1216 		data += seg;
1217 		++gfn;
1218 	}
1219 	return 0;
1220 }
1221 
1222 int kvm_clear_guest_page(struct kvm *kvm, gfn_t gfn, int offset, int len)
1223 {
1224 	return kvm_write_guest_page(kvm, gfn, empty_zero_page, offset, len);
1225 }
1226 EXPORT_SYMBOL_GPL(kvm_clear_guest_page);
1227 
1228 int kvm_clear_guest(struct kvm *kvm, gpa_t gpa, unsigned long len)
1229 {
1230 	gfn_t gfn = gpa >> PAGE_SHIFT;
1231 	int seg;
1232 	int offset = offset_in_page(gpa);
1233 	int ret;
1234 
1235         while ((seg = next_segment(len, offset)) != 0) {
1236 		ret = kvm_clear_guest_page(kvm, gfn, offset, seg);
1237 		if (ret < 0)
1238 			return ret;
1239 		offset = 0;
1240 		len -= seg;
1241 		++gfn;
1242 	}
1243 	return 0;
1244 }
1245 EXPORT_SYMBOL_GPL(kvm_clear_guest);
1246 
1247 void mark_page_dirty(struct kvm *kvm, gfn_t gfn)
1248 {
1249 	struct kvm_memory_slot *memslot;
1250 
1251 	memslot = gfn_to_memslot(kvm, gfn);
1252 	if (memslot && memslot->dirty_bitmap) {
1253 		unsigned long rel_gfn = gfn - memslot->base_gfn;
1254 
1255 		generic___set_le_bit(rel_gfn, memslot->dirty_bitmap);
1256 	}
1257 }
1258 
1259 /*
1260  * The vCPU has executed a HLT instruction with in-kernel mode enabled.
1261  */
1262 void kvm_vcpu_block(struct kvm_vcpu *vcpu)
1263 {
1264 	DEFINE_WAIT(wait);
1265 
1266 	for (;;) {
1267 		prepare_to_wait(&vcpu->wq, &wait, TASK_INTERRUPTIBLE);
1268 
1269 		if (kvm_arch_vcpu_runnable(vcpu)) {
1270 			kvm_make_request(KVM_REQ_UNHALT, vcpu);
1271 			break;
1272 		}
1273 		if (kvm_cpu_has_pending_timer(vcpu))
1274 			break;
1275 		if (signal_pending(current))
1276 			break;
1277 
1278 		schedule();
1279 	}
1280 
1281 	finish_wait(&vcpu->wq, &wait);
1282 }
1283 
1284 void kvm_resched(struct kvm_vcpu *vcpu)
1285 {
1286 	if (!need_resched())
1287 		return;
1288 	cond_resched();
1289 }
1290 EXPORT_SYMBOL_GPL(kvm_resched);
1291 
1292 void kvm_vcpu_on_spin(struct kvm_vcpu *vcpu)
1293 {
1294 	ktime_t expires;
1295 	DEFINE_WAIT(wait);
1296 
1297 	prepare_to_wait(&vcpu->wq, &wait, TASK_INTERRUPTIBLE);
1298 
1299 	/* Sleep for 100 us, and hope lock-holder got scheduled */
1300 	expires = ktime_add_ns(ktime_get(), 100000UL);
1301 	schedule_hrtimeout(&expires, HRTIMER_MODE_ABS);
1302 
1303 	finish_wait(&vcpu->wq, &wait);
1304 }
1305 EXPORT_SYMBOL_GPL(kvm_vcpu_on_spin);
1306 
1307 static int kvm_vcpu_fault(struct vm_area_struct *vma, struct vm_fault *vmf)
1308 {
1309 	struct kvm_vcpu *vcpu = vma->vm_file->private_data;
1310 	struct page *page;
1311 
1312 	if (vmf->pgoff == 0)
1313 		page = virt_to_page(vcpu->run);
1314 #ifdef CONFIG_X86
1315 	else if (vmf->pgoff == KVM_PIO_PAGE_OFFSET)
1316 		page = virt_to_page(vcpu->arch.pio_data);
1317 #endif
1318 #ifdef KVM_COALESCED_MMIO_PAGE_OFFSET
1319 	else if (vmf->pgoff == KVM_COALESCED_MMIO_PAGE_OFFSET)
1320 		page = virt_to_page(vcpu->kvm->coalesced_mmio_ring);
1321 #endif
1322 	else
1323 		return VM_FAULT_SIGBUS;
1324 	get_page(page);
1325 	vmf->page = page;
1326 	return 0;
1327 }
1328 
1329 static const struct vm_operations_struct kvm_vcpu_vm_ops = {
1330 	.fault = kvm_vcpu_fault,
1331 };
1332 
1333 static int kvm_vcpu_mmap(struct file *file, struct vm_area_struct *vma)
1334 {
1335 	vma->vm_ops = &kvm_vcpu_vm_ops;
1336 	return 0;
1337 }
1338 
1339 static int kvm_vcpu_release(struct inode *inode, struct file *filp)
1340 {
1341 	struct kvm_vcpu *vcpu = filp->private_data;
1342 
1343 	kvm_put_kvm(vcpu->kvm);
1344 	return 0;
1345 }
1346 
1347 static struct file_operations kvm_vcpu_fops = {
1348 	.release        = kvm_vcpu_release,
1349 	.unlocked_ioctl = kvm_vcpu_ioctl,
1350 	.compat_ioctl   = kvm_vcpu_ioctl,
1351 	.mmap           = kvm_vcpu_mmap,
1352 	.llseek		= noop_llseek,
1353 };
1354 
1355 /*
1356  * Allocates an inode for the vcpu.
1357  */
1358 static int create_vcpu_fd(struct kvm_vcpu *vcpu)
1359 {
1360 	return anon_inode_getfd("kvm-vcpu", &kvm_vcpu_fops, vcpu, O_RDWR);
1361 }
1362 
1363 /*
1364  * Creates some virtual cpus.  Good luck creating more than one.
1365  */
1366 static int kvm_vm_ioctl_create_vcpu(struct kvm *kvm, u32 id)
1367 {
1368 	int r;
1369 	struct kvm_vcpu *vcpu, *v;
1370 
1371 	vcpu = kvm_arch_vcpu_create(kvm, id);
1372 	if (IS_ERR(vcpu))
1373 		return PTR_ERR(vcpu);
1374 
1375 	preempt_notifier_init(&vcpu->preempt_notifier, &kvm_preempt_ops);
1376 
1377 	r = kvm_arch_vcpu_setup(vcpu);
1378 	if (r)
1379 		return r;
1380 
1381 	mutex_lock(&kvm->lock);
1382 	if (atomic_read(&kvm->online_vcpus) == KVM_MAX_VCPUS) {
1383 		r = -EINVAL;
1384 		goto vcpu_destroy;
1385 	}
1386 
1387 	kvm_for_each_vcpu(r, v, kvm)
1388 		if (v->vcpu_id == id) {
1389 			r = -EEXIST;
1390 			goto vcpu_destroy;
1391 		}
1392 
1393 	BUG_ON(kvm->vcpus[atomic_read(&kvm->online_vcpus)]);
1394 
1395 	/* Now it's all set up, let userspace reach it */
1396 	kvm_get_kvm(kvm);
1397 	r = create_vcpu_fd(vcpu);
1398 	if (r < 0) {
1399 		kvm_put_kvm(kvm);
1400 		goto vcpu_destroy;
1401 	}
1402 
1403 	kvm->vcpus[atomic_read(&kvm->online_vcpus)] = vcpu;
1404 	smp_wmb();
1405 	atomic_inc(&kvm->online_vcpus);
1406 
1407 #ifdef CONFIG_KVM_APIC_ARCHITECTURE
1408 	if (kvm->bsp_vcpu_id == id)
1409 		kvm->bsp_vcpu = vcpu;
1410 #endif
1411 	mutex_unlock(&kvm->lock);
1412 	return r;
1413 
1414 vcpu_destroy:
1415 	mutex_unlock(&kvm->lock);
1416 	kvm_arch_vcpu_destroy(vcpu);
1417 	return r;
1418 }
1419 
1420 static int kvm_vcpu_ioctl_set_sigmask(struct kvm_vcpu *vcpu, sigset_t *sigset)
1421 {
1422 	if (sigset) {
1423 		sigdelsetmask(sigset, sigmask(SIGKILL)|sigmask(SIGSTOP));
1424 		vcpu->sigset_active = 1;
1425 		vcpu->sigset = *sigset;
1426 	} else
1427 		vcpu->sigset_active = 0;
1428 	return 0;
1429 }
1430 
1431 static long kvm_vcpu_ioctl(struct file *filp,
1432 			   unsigned int ioctl, unsigned long arg)
1433 {
1434 	struct kvm_vcpu *vcpu = filp->private_data;
1435 	void __user *argp = (void __user *)arg;
1436 	int r;
1437 	struct kvm_fpu *fpu = NULL;
1438 	struct kvm_sregs *kvm_sregs = NULL;
1439 
1440 	if (vcpu->kvm->mm != current->mm)
1441 		return -EIO;
1442 
1443 #if defined(CONFIG_S390) || defined(CONFIG_PPC)
1444 	/*
1445 	 * Special cases: vcpu ioctls that are asynchronous to vcpu execution,
1446 	 * so vcpu_load() would break it.
1447 	 */
1448 	if (ioctl == KVM_S390_INTERRUPT || ioctl == KVM_INTERRUPT)
1449 		return kvm_arch_vcpu_ioctl(filp, ioctl, arg);
1450 #endif
1451 
1452 
1453 	vcpu_load(vcpu);
1454 	switch (ioctl) {
1455 	case KVM_RUN:
1456 		r = -EINVAL;
1457 		if (arg)
1458 			goto out;
1459 		r = kvm_arch_vcpu_ioctl_run(vcpu, vcpu->run);
1460 		break;
1461 	case KVM_GET_REGS: {
1462 		struct kvm_regs *kvm_regs;
1463 
1464 		r = -ENOMEM;
1465 		kvm_regs = kzalloc(sizeof(struct kvm_regs), GFP_KERNEL);
1466 		if (!kvm_regs)
1467 			goto out;
1468 		r = kvm_arch_vcpu_ioctl_get_regs(vcpu, kvm_regs);
1469 		if (r)
1470 			goto out_free1;
1471 		r = -EFAULT;
1472 		if (copy_to_user(argp, kvm_regs, sizeof(struct kvm_regs)))
1473 			goto out_free1;
1474 		r = 0;
1475 out_free1:
1476 		kfree(kvm_regs);
1477 		break;
1478 	}
1479 	case KVM_SET_REGS: {
1480 		struct kvm_regs *kvm_regs;
1481 
1482 		r = -ENOMEM;
1483 		kvm_regs = kzalloc(sizeof(struct kvm_regs), GFP_KERNEL);
1484 		if (!kvm_regs)
1485 			goto out;
1486 		r = -EFAULT;
1487 		if (copy_from_user(kvm_regs, argp, sizeof(struct kvm_regs)))
1488 			goto out_free2;
1489 		r = kvm_arch_vcpu_ioctl_set_regs(vcpu, kvm_regs);
1490 		if (r)
1491 			goto out_free2;
1492 		r = 0;
1493 out_free2:
1494 		kfree(kvm_regs);
1495 		break;
1496 	}
1497 	case KVM_GET_SREGS: {
1498 		kvm_sregs = kzalloc(sizeof(struct kvm_sregs), GFP_KERNEL);
1499 		r = -ENOMEM;
1500 		if (!kvm_sregs)
1501 			goto out;
1502 		r = kvm_arch_vcpu_ioctl_get_sregs(vcpu, kvm_sregs);
1503 		if (r)
1504 			goto out;
1505 		r = -EFAULT;
1506 		if (copy_to_user(argp, kvm_sregs, sizeof(struct kvm_sregs)))
1507 			goto out;
1508 		r = 0;
1509 		break;
1510 	}
1511 	case KVM_SET_SREGS: {
1512 		kvm_sregs = kmalloc(sizeof(struct kvm_sregs), GFP_KERNEL);
1513 		r = -ENOMEM;
1514 		if (!kvm_sregs)
1515 			goto out;
1516 		r = -EFAULT;
1517 		if (copy_from_user(kvm_sregs, argp, sizeof(struct kvm_sregs)))
1518 			goto out;
1519 		r = kvm_arch_vcpu_ioctl_set_sregs(vcpu, kvm_sregs);
1520 		if (r)
1521 			goto out;
1522 		r = 0;
1523 		break;
1524 	}
1525 	case KVM_GET_MP_STATE: {
1526 		struct kvm_mp_state mp_state;
1527 
1528 		r = kvm_arch_vcpu_ioctl_get_mpstate(vcpu, &mp_state);
1529 		if (r)
1530 			goto out;
1531 		r = -EFAULT;
1532 		if (copy_to_user(argp, &mp_state, sizeof mp_state))
1533 			goto out;
1534 		r = 0;
1535 		break;
1536 	}
1537 	case KVM_SET_MP_STATE: {
1538 		struct kvm_mp_state mp_state;
1539 
1540 		r = -EFAULT;
1541 		if (copy_from_user(&mp_state, argp, sizeof mp_state))
1542 			goto out;
1543 		r = kvm_arch_vcpu_ioctl_set_mpstate(vcpu, &mp_state);
1544 		if (r)
1545 			goto out;
1546 		r = 0;
1547 		break;
1548 	}
1549 	case KVM_TRANSLATE: {
1550 		struct kvm_translation tr;
1551 
1552 		r = -EFAULT;
1553 		if (copy_from_user(&tr, argp, sizeof tr))
1554 			goto out;
1555 		r = kvm_arch_vcpu_ioctl_translate(vcpu, &tr);
1556 		if (r)
1557 			goto out;
1558 		r = -EFAULT;
1559 		if (copy_to_user(argp, &tr, sizeof tr))
1560 			goto out;
1561 		r = 0;
1562 		break;
1563 	}
1564 	case KVM_SET_GUEST_DEBUG: {
1565 		struct kvm_guest_debug dbg;
1566 
1567 		r = -EFAULT;
1568 		if (copy_from_user(&dbg, argp, sizeof dbg))
1569 			goto out;
1570 		r = kvm_arch_vcpu_ioctl_set_guest_debug(vcpu, &dbg);
1571 		if (r)
1572 			goto out;
1573 		r = 0;
1574 		break;
1575 	}
1576 	case KVM_SET_SIGNAL_MASK: {
1577 		struct kvm_signal_mask __user *sigmask_arg = argp;
1578 		struct kvm_signal_mask kvm_sigmask;
1579 		sigset_t sigset, *p;
1580 
1581 		p = NULL;
1582 		if (argp) {
1583 			r = -EFAULT;
1584 			if (copy_from_user(&kvm_sigmask, argp,
1585 					   sizeof kvm_sigmask))
1586 				goto out;
1587 			r = -EINVAL;
1588 			if (kvm_sigmask.len != sizeof sigset)
1589 				goto out;
1590 			r = -EFAULT;
1591 			if (copy_from_user(&sigset, sigmask_arg->sigset,
1592 					   sizeof sigset))
1593 				goto out;
1594 			p = &sigset;
1595 		}
1596 		r = kvm_vcpu_ioctl_set_sigmask(vcpu, p);
1597 		break;
1598 	}
1599 	case KVM_GET_FPU: {
1600 		fpu = kzalloc(sizeof(struct kvm_fpu), GFP_KERNEL);
1601 		r = -ENOMEM;
1602 		if (!fpu)
1603 			goto out;
1604 		r = kvm_arch_vcpu_ioctl_get_fpu(vcpu, fpu);
1605 		if (r)
1606 			goto out;
1607 		r = -EFAULT;
1608 		if (copy_to_user(argp, fpu, sizeof(struct kvm_fpu)))
1609 			goto out;
1610 		r = 0;
1611 		break;
1612 	}
1613 	case KVM_SET_FPU: {
1614 		fpu = kmalloc(sizeof(struct kvm_fpu), GFP_KERNEL);
1615 		r = -ENOMEM;
1616 		if (!fpu)
1617 			goto out;
1618 		r = -EFAULT;
1619 		if (copy_from_user(fpu, argp, sizeof(struct kvm_fpu)))
1620 			goto out;
1621 		r = kvm_arch_vcpu_ioctl_set_fpu(vcpu, fpu);
1622 		if (r)
1623 			goto out;
1624 		r = 0;
1625 		break;
1626 	}
1627 	default:
1628 		r = kvm_arch_vcpu_ioctl(filp, ioctl, arg);
1629 	}
1630 out:
1631 	vcpu_put(vcpu);
1632 	kfree(fpu);
1633 	kfree(kvm_sregs);
1634 	return r;
1635 }
1636 
1637 static long kvm_vm_ioctl(struct file *filp,
1638 			   unsigned int ioctl, unsigned long arg)
1639 {
1640 	struct kvm *kvm = filp->private_data;
1641 	void __user *argp = (void __user *)arg;
1642 	int r;
1643 
1644 	if (kvm->mm != current->mm)
1645 		return -EIO;
1646 	switch (ioctl) {
1647 	case KVM_CREATE_VCPU:
1648 		r = kvm_vm_ioctl_create_vcpu(kvm, arg);
1649 		if (r < 0)
1650 			goto out;
1651 		break;
1652 	case KVM_SET_USER_MEMORY_REGION: {
1653 		struct kvm_userspace_memory_region kvm_userspace_mem;
1654 
1655 		r = -EFAULT;
1656 		if (copy_from_user(&kvm_userspace_mem, argp,
1657 						sizeof kvm_userspace_mem))
1658 			goto out;
1659 
1660 		r = kvm_vm_ioctl_set_memory_region(kvm, &kvm_userspace_mem, 1);
1661 		if (r)
1662 			goto out;
1663 		break;
1664 	}
1665 	case KVM_GET_DIRTY_LOG: {
1666 		struct kvm_dirty_log log;
1667 
1668 		r = -EFAULT;
1669 		if (copy_from_user(&log, argp, sizeof log))
1670 			goto out;
1671 		r = kvm_vm_ioctl_get_dirty_log(kvm, &log);
1672 		if (r)
1673 			goto out;
1674 		break;
1675 	}
1676 #ifdef KVM_COALESCED_MMIO_PAGE_OFFSET
1677 	case KVM_REGISTER_COALESCED_MMIO: {
1678 		struct kvm_coalesced_mmio_zone zone;
1679 		r = -EFAULT;
1680 		if (copy_from_user(&zone, argp, sizeof zone))
1681 			goto out;
1682 		r = kvm_vm_ioctl_register_coalesced_mmio(kvm, &zone);
1683 		if (r)
1684 			goto out;
1685 		r = 0;
1686 		break;
1687 	}
1688 	case KVM_UNREGISTER_COALESCED_MMIO: {
1689 		struct kvm_coalesced_mmio_zone zone;
1690 		r = -EFAULT;
1691 		if (copy_from_user(&zone, argp, sizeof zone))
1692 			goto out;
1693 		r = kvm_vm_ioctl_unregister_coalesced_mmio(kvm, &zone);
1694 		if (r)
1695 			goto out;
1696 		r = 0;
1697 		break;
1698 	}
1699 #endif
1700 	case KVM_IRQFD: {
1701 		struct kvm_irqfd data;
1702 
1703 		r = -EFAULT;
1704 		if (copy_from_user(&data, argp, sizeof data))
1705 			goto out;
1706 		r = kvm_irqfd(kvm, data.fd, data.gsi, data.flags);
1707 		break;
1708 	}
1709 	case KVM_IOEVENTFD: {
1710 		struct kvm_ioeventfd data;
1711 
1712 		r = -EFAULT;
1713 		if (copy_from_user(&data, argp, sizeof data))
1714 			goto out;
1715 		r = kvm_ioeventfd(kvm, &data);
1716 		break;
1717 	}
1718 #ifdef CONFIG_KVM_APIC_ARCHITECTURE
1719 	case KVM_SET_BOOT_CPU_ID:
1720 		r = 0;
1721 		mutex_lock(&kvm->lock);
1722 		if (atomic_read(&kvm->online_vcpus) != 0)
1723 			r = -EBUSY;
1724 		else
1725 			kvm->bsp_vcpu_id = arg;
1726 		mutex_unlock(&kvm->lock);
1727 		break;
1728 #endif
1729 	default:
1730 		r = kvm_arch_vm_ioctl(filp, ioctl, arg);
1731 		if (r == -ENOTTY)
1732 			r = kvm_vm_ioctl_assigned_device(kvm, ioctl, arg);
1733 	}
1734 out:
1735 	return r;
1736 }
1737 
1738 #ifdef CONFIG_COMPAT
1739 struct compat_kvm_dirty_log {
1740 	__u32 slot;
1741 	__u32 padding1;
1742 	union {
1743 		compat_uptr_t dirty_bitmap; /* one bit per page */
1744 		__u64 padding2;
1745 	};
1746 };
1747 
1748 static long kvm_vm_compat_ioctl(struct file *filp,
1749 			   unsigned int ioctl, unsigned long arg)
1750 {
1751 	struct kvm *kvm = filp->private_data;
1752 	int r;
1753 
1754 	if (kvm->mm != current->mm)
1755 		return -EIO;
1756 	switch (ioctl) {
1757 	case KVM_GET_DIRTY_LOG: {
1758 		struct compat_kvm_dirty_log compat_log;
1759 		struct kvm_dirty_log log;
1760 
1761 		r = -EFAULT;
1762 		if (copy_from_user(&compat_log, (void __user *)arg,
1763 				   sizeof(compat_log)))
1764 			goto out;
1765 		log.slot	 = compat_log.slot;
1766 		log.padding1	 = compat_log.padding1;
1767 		log.padding2	 = compat_log.padding2;
1768 		log.dirty_bitmap = compat_ptr(compat_log.dirty_bitmap);
1769 
1770 		r = kvm_vm_ioctl_get_dirty_log(kvm, &log);
1771 		if (r)
1772 			goto out;
1773 		break;
1774 	}
1775 	default:
1776 		r = kvm_vm_ioctl(filp, ioctl, arg);
1777 	}
1778 
1779 out:
1780 	return r;
1781 }
1782 #endif
1783 
1784 static int kvm_vm_fault(struct vm_area_struct *vma, struct vm_fault *vmf)
1785 {
1786 	struct page *page[1];
1787 	unsigned long addr;
1788 	int npages;
1789 	gfn_t gfn = vmf->pgoff;
1790 	struct kvm *kvm = vma->vm_file->private_data;
1791 
1792 	addr = gfn_to_hva(kvm, gfn);
1793 	if (kvm_is_error_hva(addr))
1794 		return VM_FAULT_SIGBUS;
1795 
1796 	npages = get_user_pages(current, current->mm, addr, 1, 1, 0, page,
1797 				NULL);
1798 	if (unlikely(npages != 1))
1799 		return VM_FAULT_SIGBUS;
1800 
1801 	vmf->page = page[0];
1802 	return 0;
1803 }
1804 
1805 static const struct vm_operations_struct kvm_vm_vm_ops = {
1806 	.fault = kvm_vm_fault,
1807 };
1808 
1809 static int kvm_vm_mmap(struct file *file, struct vm_area_struct *vma)
1810 {
1811 	vma->vm_ops = &kvm_vm_vm_ops;
1812 	return 0;
1813 }
1814 
1815 static struct file_operations kvm_vm_fops = {
1816 	.release        = kvm_vm_release,
1817 	.unlocked_ioctl = kvm_vm_ioctl,
1818 #ifdef CONFIG_COMPAT
1819 	.compat_ioctl   = kvm_vm_compat_ioctl,
1820 #endif
1821 	.mmap           = kvm_vm_mmap,
1822 	.llseek		= noop_llseek,
1823 };
1824 
1825 static int kvm_dev_ioctl_create_vm(void)
1826 {
1827 	int fd, r;
1828 	struct kvm *kvm;
1829 
1830 	kvm = kvm_create_vm();
1831 	if (IS_ERR(kvm))
1832 		return PTR_ERR(kvm);
1833 #ifdef KVM_COALESCED_MMIO_PAGE_OFFSET
1834 	r = kvm_coalesced_mmio_init(kvm);
1835 	if (r < 0) {
1836 		kvm_put_kvm(kvm);
1837 		return r;
1838 	}
1839 #endif
1840 	fd = anon_inode_getfd("kvm-vm", &kvm_vm_fops, kvm, O_RDWR);
1841 	if (fd < 0)
1842 		kvm_put_kvm(kvm);
1843 
1844 	return fd;
1845 }
1846 
1847 static long kvm_dev_ioctl_check_extension_generic(long arg)
1848 {
1849 	switch (arg) {
1850 	case KVM_CAP_USER_MEMORY:
1851 	case KVM_CAP_DESTROY_MEMORY_REGION_WORKS:
1852 	case KVM_CAP_JOIN_MEMORY_REGIONS_WORKS:
1853 #ifdef CONFIG_KVM_APIC_ARCHITECTURE
1854 	case KVM_CAP_SET_BOOT_CPU_ID:
1855 #endif
1856 	case KVM_CAP_INTERNAL_ERROR_DATA:
1857 		return 1;
1858 #ifdef CONFIG_HAVE_KVM_IRQCHIP
1859 	case KVM_CAP_IRQ_ROUTING:
1860 		return KVM_MAX_IRQ_ROUTES;
1861 #endif
1862 	default:
1863 		break;
1864 	}
1865 	return kvm_dev_ioctl_check_extension(arg);
1866 }
1867 
1868 static long kvm_dev_ioctl(struct file *filp,
1869 			  unsigned int ioctl, unsigned long arg)
1870 {
1871 	long r = -EINVAL;
1872 
1873 	switch (ioctl) {
1874 	case KVM_GET_API_VERSION:
1875 		r = -EINVAL;
1876 		if (arg)
1877 			goto out;
1878 		r = KVM_API_VERSION;
1879 		break;
1880 	case KVM_CREATE_VM:
1881 		r = -EINVAL;
1882 		if (arg)
1883 			goto out;
1884 		r = kvm_dev_ioctl_create_vm();
1885 		break;
1886 	case KVM_CHECK_EXTENSION:
1887 		r = kvm_dev_ioctl_check_extension_generic(arg);
1888 		break;
1889 	case KVM_GET_VCPU_MMAP_SIZE:
1890 		r = -EINVAL;
1891 		if (arg)
1892 			goto out;
1893 		r = PAGE_SIZE;     /* struct kvm_run */
1894 #ifdef CONFIG_X86
1895 		r += PAGE_SIZE;    /* pio data page */
1896 #endif
1897 #ifdef KVM_COALESCED_MMIO_PAGE_OFFSET
1898 		r += PAGE_SIZE;    /* coalesced mmio ring page */
1899 #endif
1900 		break;
1901 	case KVM_TRACE_ENABLE:
1902 	case KVM_TRACE_PAUSE:
1903 	case KVM_TRACE_DISABLE:
1904 		r = -EOPNOTSUPP;
1905 		break;
1906 	default:
1907 		return kvm_arch_dev_ioctl(filp, ioctl, arg);
1908 	}
1909 out:
1910 	return r;
1911 }
1912 
1913 static struct file_operations kvm_chardev_ops = {
1914 	.unlocked_ioctl = kvm_dev_ioctl,
1915 	.compat_ioctl   = kvm_dev_ioctl,
1916 	.llseek		= noop_llseek,
1917 };
1918 
1919 static struct miscdevice kvm_dev = {
1920 	KVM_MINOR,
1921 	"kvm",
1922 	&kvm_chardev_ops,
1923 };
1924 
1925 static void hardware_enable(void *junk)
1926 {
1927 	int cpu = raw_smp_processor_id();
1928 	int r;
1929 
1930 	if (cpumask_test_cpu(cpu, cpus_hardware_enabled))
1931 		return;
1932 
1933 	cpumask_set_cpu(cpu, cpus_hardware_enabled);
1934 
1935 	r = kvm_arch_hardware_enable(NULL);
1936 
1937 	if (r) {
1938 		cpumask_clear_cpu(cpu, cpus_hardware_enabled);
1939 		atomic_inc(&hardware_enable_failed);
1940 		printk(KERN_INFO "kvm: enabling virtualization on "
1941 				 "CPU%d failed\n", cpu);
1942 	}
1943 }
1944 
1945 static void hardware_disable(void *junk)
1946 {
1947 	int cpu = raw_smp_processor_id();
1948 
1949 	if (!cpumask_test_cpu(cpu, cpus_hardware_enabled))
1950 		return;
1951 	cpumask_clear_cpu(cpu, cpus_hardware_enabled);
1952 	kvm_arch_hardware_disable(NULL);
1953 }
1954 
1955 static void hardware_disable_all_nolock(void)
1956 {
1957 	BUG_ON(!kvm_usage_count);
1958 
1959 	kvm_usage_count--;
1960 	if (!kvm_usage_count)
1961 		on_each_cpu(hardware_disable, NULL, 1);
1962 }
1963 
1964 static void hardware_disable_all(void)
1965 {
1966 	spin_lock(&kvm_lock);
1967 	hardware_disable_all_nolock();
1968 	spin_unlock(&kvm_lock);
1969 }
1970 
1971 static int hardware_enable_all(void)
1972 {
1973 	int r = 0;
1974 
1975 	spin_lock(&kvm_lock);
1976 
1977 	kvm_usage_count++;
1978 	if (kvm_usage_count == 1) {
1979 		atomic_set(&hardware_enable_failed, 0);
1980 		on_each_cpu(hardware_enable, NULL, 1);
1981 
1982 		if (atomic_read(&hardware_enable_failed)) {
1983 			hardware_disable_all_nolock();
1984 			r = -EBUSY;
1985 		}
1986 	}
1987 
1988 	spin_unlock(&kvm_lock);
1989 
1990 	return r;
1991 }
1992 
1993 static int kvm_cpu_hotplug(struct notifier_block *notifier, unsigned long val,
1994 			   void *v)
1995 {
1996 	int cpu = (long)v;
1997 
1998 	if (!kvm_usage_count)
1999 		return NOTIFY_OK;
2000 
2001 	val &= ~CPU_TASKS_FROZEN;
2002 	switch (val) {
2003 	case CPU_DYING:
2004 		printk(KERN_INFO "kvm: disabling virtualization on CPU%d\n",
2005 		       cpu);
2006 		hardware_disable(NULL);
2007 		break;
2008 	case CPU_STARTING:
2009 		printk(KERN_INFO "kvm: enabling virtualization on CPU%d\n",
2010 		       cpu);
2011 		spin_lock(&kvm_lock);
2012 		hardware_enable(NULL);
2013 		spin_unlock(&kvm_lock);
2014 		break;
2015 	}
2016 	return NOTIFY_OK;
2017 }
2018 
2019 
2020 asmlinkage void kvm_handle_fault_on_reboot(void)
2021 {
2022 	if (kvm_rebooting) {
2023 		/* spin while reset goes on */
2024 		local_irq_enable();
2025 		while (true)
2026 			cpu_relax();
2027 	}
2028 	/* Fault while not rebooting.  We want the trace. */
2029 	BUG();
2030 }
2031 EXPORT_SYMBOL_GPL(kvm_handle_fault_on_reboot);
2032 
2033 static int kvm_reboot(struct notifier_block *notifier, unsigned long val,
2034 		      void *v)
2035 {
2036 	/*
2037 	 * Some (well, at least mine) BIOSes hang on reboot if
2038 	 * in vmx root mode.
2039 	 *
2040 	 * And Intel TXT required VMX off for all cpu when system shutdown.
2041 	 */
2042 	printk(KERN_INFO "kvm: exiting hardware virtualization\n");
2043 	kvm_rebooting = true;
2044 	on_each_cpu(hardware_disable, NULL, 1);
2045 	return NOTIFY_OK;
2046 }
2047 
2048 static struct notifier_block kvm_reboot_notifier = {
2049 	.notifier_call = kvm_reboot,
2050 	.priority = 0,
2051 };
2052 
2053 static void kvm_io_bus_destroy(struct kvm_io_bus *bus)
2054 {
2055 	int i;
2056 
2057 	for (i = 0; i < bus->dev_count; i++) {
2058 		struct kvm_io_device *pos = bus->devs[i];
2059 
2060 		kvm_iodevice_destructor(pos);
2061 	}
2062 	kfree(bus);
2063 }
2064 
2065 /* kvm_io_bus_write - called under kvm->slots_lock */
2066 int kvm_io_bus_write(struct kvm *kvm, enum kvm_bus bus_idx, gpa_t addr,
2067 		     int len, const void *val)
2068 {
2069 	int i;
2070 	struct kvm_io_bus *bus;
2071 
2072 	bus = srcu_dereference(kvm->buses[bus_idx], &kvm->srcu);
2073 	for (i = 0; i < bus->dev_count; i++)
2074 		if (!kvm_iodevice_write(bus->devs[i], addr, len, val))
2075 			return 0;
2076 	return -EOPNOTSUPP;
2077 }
2078 
2079 /* kvm_io_bus_read - called under kvm->slots_lock */
2080 int kvm_io_bus_read(struct kvm *kvm, enum kvm_bus bus_idx, gpa_t addr,
2081 		    int len, void *val)
2082 {
2083 	int i;
2084 	struct kvm_io_bus *bus;
2085 
2086 	bus = srcu_dereference(kvm->buses[bus_idx], &kvm->srcu);
2087 	for (i = 0; i < bus->dev_count; i++)
2088 		if (!kvm_iodevice_read(bus->devs[i], addr, len, val))
2089 			return 0;
2090 	return -EOPNOTSUPP;
2091 }
2092 
2093 /* Caller must hold slots_lock. */
2094 int kvm_io_bus_register_dev(struct kvm *kvm, enum kvm_bus bus_idx,
2095 			    struct kvm_io_device *dev)
2096 {
2097 	struct kvm_io_bus *new_bus, *bus;
2098 
2099 	bus = kvm->buses[bus_idx];
2100 	if (bus->dev_count > NR_IOBUS_DEVS-1)
2101 		return -ENOSPC;
2102 
2103 	new_bus = kzalloc(sizeof(struct kvm_io_bus), GFP_KERNEL);
2104 	if (!new_bus)
2105 		return -ENOMEM;
2106 	memcpy(new_bus, bus, sizeof(struct kvm_io_bus));
2107 	new_bus->devs[new_bus->dev_count++] = dev;
2108 	rcu_assign_pointer(kvm->buses[bus_idx], new_bus);
2109 	synchronize_srcu_expedited(&kvm->srcu);
2110 	kfree(bus);
2111 
2112 	return 0;
2113 }
2114 
2115 /* Caller must hold slots_lock. */
2116 int kvm_io_bus_unregister_dev(struct kvm *kvm, enum kvm_bus bus_idx,
2117 			      struct kvm_io_device *dev)
2118 {
2119 	int i, r;
2120 	struct kvm_io_bus *new_bus, *bus;
2121 
2122 	new_bus = kzalloc(sizeof(struct kvm_io_bus), GFP_KERNEL);
2123 	if (!new_bus)
2124 		return -ENOMEM;
2125 
2126 	bus = kvm->buses[bus_idx];
2127 	memcpy(new_bus, bus, sizeof(struct kvm_io_bus));
2128 
2129 	r = -ENOENT;
2130 	for (i = 0; i < new_bus->dev_count; i++)
2131 		if (new_bus->devs[i] == dev) {
2132 			r = 0;
2133 			new_bus->devs[i] = new_bus->devs[--new_bus->dev_count];
2134 			break;
2135 		}
2136 
2137 	if (r) {
2138 		kfree(new_bus);
2139 		return r;
2140 	}
2141 
2142 	rcu_assign_pointer(kvm->buses[bus_idx], new_bus);
2143 	synchronize_srcu_expedited(&kvm->srcu);
2144 	kfree(bus);
2145 	return r;
2146 }
2147 
2148 static struct notifier_block kvm_cpu_notifier = {
2149 	.notifier_call = kvm_cpu_hotplug,
2150 };
2151 
2152 static int vm_stat_get(void *_offset, u64 *val)
2153 {
2154 	unsigned offset = (long)_offset;
2155 	struct kvm *kvm;
2156 
2157 	*val = 0;
2158 	spin_lock(&kvm_lock);
2159 	list_for_each_entry(kvm, &vm_list, vm_list)
2160 		*val += *(u32 *)((void *)kvm + offset);
2161 	spin_unlock(&kvm_lock);
2162 	return 0;
2163 }
2164 
2165 DEFINE_SIMPLE_ATTRIBUTE(vm_stat_fops, vm_stat_get, NULL, "%llu\n");
2166 
2167 static int vcpu_stat_get(void *_offset, u64 *val)
2168 {
2169 	unsigned offset = (long)_offset;
2170 	struct kvm *kvm;
2171 	struct kvm_vcpu *vcpu;
2172 	int i;
2173 
2174 	*val = 0;
2175 	spin_lock(&kvm_lock);
2176 	list_for_each_entry(kvm, &vm_list, vm_list)
2177 		kvm_for_each_vcpu(i, vcpu, kvm)
2178 			*val += *(u32 *)((void *)vcpu + offset);
2179 
2180 	spin_unlock(&kvm_lock);
2181 	return 0;
2182 }
2183 
2184 DEFINE_SIMPLE_ATTRIBUTE(vcpu_stat_fops, vcpu_stat_get, NULL, "%llu\n");
2185 
2186 static const struct file_operations *stat_fops[] = {
2187 	[KVM_STAT_VCPU] = &vcpu_stat_fops,
2188 	[KVM_STAT_VM]   = &vm_stat_fops,
2189 };
2190 
2191 static void kvm_init_debug(void)
2192 {
2193 	struct kvm_stats_debugfs_item *p;
2194 
2195 	kvm_debugfs_dir = debugfs_create_dir("kvm", NULL);
2196 	for (p = debugfs_entries; p->name; ++p)
2197 		p->dentry = debugfs_create_file(p->name, 0444, kvm_debugfs_dir,
2198 						(void *)(long)p->offset,
2199 						stat_fops[p->kind]);
2200 }
2201 
2202 static void kvm_exit_debug(void)
2203 {
2204 	struct kvm_stats_debugfs_item *p;
2205 
2206 	for (p = debugfs_entries; p->name; ++p)
2207 		debugfs_remove(p->dentry);
2208 	debugfs_remove(kvm_debugfs_dir);
2209 }
2210 
2211 static int kvm_suspend(struct sys_device *dev, pm_message_t state)
2212 {
2213 	if (kvm_usage_count)
2214 		hardware_disable(NULL);
2215 	return 0;
2216 }
2217 
2218 static int kvm_resume(struct sys_device *dev)
2219 {
2220 	if (kvm_usage_count) {
2221 		WARN_ON(spin_is_locked(&kvm_lock));
2222 		hardware_enable(NULL);
2223 	}
2224 	return 0;
2225 }
2226 
2227 static struct sysdev_class kvm_sysdev_class = {
2228 	.name = "kvm",
2229 	.suspend = kvm_suspend,
2230 	.resume = kvm_resume,
2231 };
2232 
2233 static struct sys_device kvm_sysdev = {
2234 	.id = 0,
2235 	.cls = &kvm_sysdev_class,
2236 };
2237 
2238 struct page *bad_page;
2239 pfn_t bad_pfn;
2240 
2241 static inline
2242 struct kvm_vcpu *preempt_notifier_to_vcpu(struct preempt_notifier *pn)
2243 {
2244 	return container_of(pn, struct kvm_vcpu, preempt_notifier);
2245 }
2246 
2247 static void kvm_sched_in(struct preempt_notifier *pn, int cpu)
2248 {
2249 	struct kvm_vcpu *vcpu = preempt_notifier_to_vcpu(pn);
2250 
2251 	kvm_arch_vcpu_load(vcpu, cpu);
2252 }
2253 
2254 static void kvm_sched_out(struct preempt_notifier *pn,
2255 			  struct task_struct *next)
2256 {
2257 	struct kvm_vcpu *vcpu = preempt_notifier_to_vcpu(pn);
2258 
2259 	kvm_arch_vcpu_put(vcpu);
2260 }
2261 
2262 int kvm_init(void *opaque, unsigned vcpu_size, unsigned vcpu_align,
2263 		  struct module *module)
2264 {
2265 	int r;
2266 	int cpu;
2267 
2268 	r = kvm_arch_init(opaque);
2269 	if (r)
2270 		goto out_fail;
2271 
2272 	bad_page = alloc_page(GFP_KERNEL | __GFP_ZERO);
2273 
2274 	if (bad_page == NULL) {
2275 		r = -ENOMEM;
2276 		goto out;
2277 	}
2278 
2279 	bad_pfn = page_to_pfn(bad_page);
2280 
2281 	hwpoison_page = alloc_page(GFP_KERNEL | __GFP_ZERO);
2282 
2283 	if (hwpoison_page == NULL) {
2284 		r = -ENOMEM;
2285 		goto out_free_0;
2286 	}
2287 
2288 	hwpoison_pfn = page_to_pfn(hwpoison_page);
2289 
2290 	fault_page = alloc_page(GFP_KERNEL | __GFP_ZERO);
2291 
2292 	if (fault_page == NULL) {
2293 		r = -ENOMEM;
2294 		goto out_free_0;
2295 	}
2296 
2297 	fault_pfn = page_to_pfn(fault_page);
2298 
2299 	if (!zalloc_cpumask_var(&cpus_hardware_enabled, GFP_KERNEL)) {
2300 		r = -ENOMEM;
2301 		goto out_free_0;
2302 	}
2303 
2304 	r = kvm_arch_hardware_setup();
2305 	if (r < 0)
2306 		goto out_free_0a;
2307 
2308 	for_each_online_cpu(cpu) {
2309 		smp_call_function_single(cpu,
2310 				kvm_arch_check_processor_compat,
2311 				&r, 1);
2312 		if (r < 0)
2313 			goto out_free_1;
2314 	}
2315 
2316 	r = register_cpu_notifier(&kvm_cpu_notifier);
2317 	if (r)
2318 		goto out_free_2;
2319 	register_reboot_notifier(&kvm_reboot_notifier);
2320 
2321 	r = sysdev_class_register(&kvm_sysdev_class);
2322 	if (r)
2323 		goto out_free_3;
2324 
2325 	r = sysdev_register(&kvm_sysdev);
2326 	if (r)
2327 		goto out_free_4;
2328 
2329 	/* A kmem cache lets us meet the alignment requirements of fx_save. */
2330 	if (!vcpu_align)
2331 		vcpu_align = __alignof__(struct kvm_vcpu);
2332 	kvm_vcpu_cache = kmem_cache_create("kvm_vcpu", vcpu_size, vcpu_align,
2333 					   0, NULL);
2334 	if (!kvm_vcpu_cache) {
2335 		r = -ENOMEM;
2336 		goto out_free_5;
2337 	}
2338 
2339 	kvm_chardev_ops.owner = module;
2340 	kvm_vm_fops.owner = module;
2341 	kvm_vcpu_fops.owner = module;
2342 
2343 	r = misc_register(&kvm_dev);
2344 	if (r) {
2345 		printk(KERN_ERR "kvm: misc device register failed\n");
2346 		goto out_free;
2347 	}
2348 
2349 	kvm_preempt_ops.sched_in = kvm_sched_in;
2350 	kvm_preempt_ops.sched_out = kvm_sched_out;
2351 
2352 	kvm_init_debug();
2353 
2354 	return 0;
2355 
2356 out_free:
2357 	kmem_cache_destroy(kvm_vcpu_cache);
2358 out_free_5:
2359 	sysdev_unregister(&kvm_sysdev);
2360 out_free_4:
2361 	sysdev_class_unregister(&kvm_sysdev_class);
2362 out_free_3:
2363 	unregister_reboot_notifier(&kvm_reboot_notifier);
2364 	unregister_cpu_notifier(&kvm_cpu_notifier);
2365 out_free_2:
2366 out_free_1:
2367 	kvm_arch_hardware_unsetup();
2368 out_free_0a:
2369 	free_cpumask_var(cpus_hardware_enabled);
2370 out_free_0:
2371 	if (fault_page)
2372 		__free_page(fault_page);
2373 	if (hwpoison_page)
2374 		__free_page(hwpoison_page);
2375 	__free_page(bad_page);
2376 out:
2377 	kvm_arch_exit();
2378 out_fail:
2379 	return r;
2380 }
2381 EXPORT_SYMBOL_GPL(kvm_init);
2382 
2383 void kvm_exit(void)
2384 {
2385 	kvm_exit_debug();
2386 	misc_deregister(&kvm_dev);
2387 	kmem_cache_destroy(kvm_vcpu_cache);
2388 	sysdev_unregister(&kvm_sysdev);
2389 	sysdev_class_unregister(&kvm_sysdev_class);
2390 	unregister_reboot_notifier(&kvm_reboot_notifier);
2391 	unregister_cpu_notifier(&kvm_cpu_notifier);
2392 	on_each_cpu(hardware_disable, NULL, 1);
2393 	kvm_arch_hardware_unsetup();
2394 	kvm_arch_exit();
2395 	free_cpumask_var(cpus_hardware_enabled);
2396 	__free_page(hwpoison_page);
2397 	__free_page(bad_page);
2398 }
2399 EXPORT_SYMBOL_GPL(kvm_exit);
2400