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kvm tools, setup: Create private directory
[linux-2.6/next.git] / virt / kvm / kvm_main.c
blob96ebc0679415baeff88d7764b1c0e956820adad2
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/syscore_ops.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
56 #include "coalesced_mmio.h"
57 #include "async_pf.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_RAW_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 bool kvm_rebooting;
93 EXPORT_SYMBOL_GPL(kvm_rebooting);
94
95 static bool largepages_enabled = true;
96
97 static struct page *hwpoison_page;
98 static pfn_t hwpoison_pfn;
99
100 static struct page *fault_page;
101 static pfn_t fault_pfn;
102
103 inline int kvm_is_mmio_pfn(pfn_t pfn)
104 {
105 if (pfn_valid(pfn)) {
106 int reserved;
107 struct page *tail = pfn_to_page(pfn);
108 struct page *head = compound_trans_head(tail);
109 reserved = PageReserved(head);
110 if (head != tail) {
111 /*
112 * "head" is not a dangling pointer
113 * (compound_trans_head takes care of that)
114 * but the hugepage may have been splitted
115 * from under us (and we may not hold a
116 * reference count on the head page so it can
117 * be reused before we run PageReferenced), so
118 * we've to check PageTail before returning
119 * what we just read.
120 */
121 smp_rmb();
122 if (PageTail(tail))
123 return reserved;
124 }
125 return PageReserved(tail);
126 }
127
128 return true;
129 }
130
131 /*
132 * Switches to specified vcpu, until a matching vcpu_put()
133 */
134 void vcpu_load(struct kvm_vcpu *vcpu)
135 {
136 int cpu;
137
138 mutex_lock(&vcpu->mutex);
139 if (unlikely(vcpu->pid != current->pids[PIDTYPE_PID].pid)) {
140 /* The thread running this VCPU changed. */
141 struct pid *oldpid = vcpu->pid;
142 struct pid *newpid = get_task_pid(current, PIDTYPE_PID);
143 rcu_assign_pointer(vcpu->pid, newpid);
144 synchronize_rcu();
145 put_pid(oldpid);
146 }
147 cpu = get_cpu();
148 preempt_notifier_register(&vcpu->preempt_notifier);
149 kvm_arch_vcpu_load(vcpu, cpu);
150 put_cpu();
151 }
152
153 void vcpu_put(struct kvm_vcpu *vcpu)
154 {
155 preempt_disable();
156 kvm_arch_vcpu_put(vcpu);
157 preempt_notifier_unregister(&vcpu->preempt_notifier);
158 preempt_enable();
159 mutex_unlock(&vcpu->mutex);
160 }
161
162 static void ack_flush(void *_completed)
163 {
164 }
165
166 static bool make_all_cpus_request(struct kvm *kvm, unsigned int req)
167 {
168 int i, cpu, me;
169 cpumask_var_t cpus;
170 bool called = true;
171 struct kvm_vcpu *vcpu;
172
173 zalloc_cpumask_var(&cpus, GFP_ATOMIC);
174
175 me = get_cpu();
176 kvm_for_each_vcpu(i, vcpu, kvm) {
177 kvm_make_request(req, vcpu);
178 cpu = vcpu->cpu;
179
180 /* Set ->requests bit before we read ->mode */
181 smp_mb();
182
183 if (cpus != NULL && cpu != -1 && cpu != me &&
184 kvm_vcpu_exiting_guest_mode(vcpu) != OUTSIDE_GUEST_MODE)
185 cpumask_set_cpu(cpu, cpus);
186 }
187 if (unlikely(cpus == NULL))
188 smp_call_function_many(cpu_online_mask, ack_flush, NULL, 1);
189 else if (!cpumask_empty(cpus))
190 smp_call_function_many(cpus, ack_flush, NULL, 1);
191 else
192 called = false;
193 put_cpu();
194 free_cpumask_var(cpus);
195 return called;
196 }
197
198 void kvm_flush_remote_tlbs(struct kvm *kvm)
199 {
200 int dirty_count = kvm->tlbs_dirty;
201
202 smp_mb();
203 if (make_all_cpus_request(kvm, KVM_REQ_TLB_FLUSH))
204 ++kvm->stat.remote_tlb_flush;
205 cmpxchg(&kvm->tlbs_dirty, dirty_count, 0);
206 }
207
208 void kvm_reload_remote_mmus(struct kvm *kvm)
209 {
210 make_all_cpus_request(kvm, KVM_REQ_MMU_RELOAD);
211 }
212
213 int kvm_vcpu_init(struct kvm_vcpu *vcpu, struct kvm *kvm, unsigned id)
214 {
215 struct page *page;
216 int r;
217
218 mutex_init(&vcpu->mutex);
219 vcpu->cpu = -1;
220 vcpu->kvm = kvm;
221 vcpu->vcpu_id = id;
222 vcpu->pid = NULL;
223 init_waitqueue_head(&vcpu->wq);
224 kvm_async_pf_vcpu_init(vcpu);
225
226 page = alloc_page(GFP_KERNEL | __GFP_ZERO);
227 if (!page) {
228 r = -ENOMEM;
229 goto fail;
230 }
231 vcpu->run = page_address(page);
232
233 r = kvm_arch_vcpu_init(vcpu);
234 if (r < 0)
235 goto fail_free_run;
236 return 0;
237
238 fail_free_run:
239 free_page((unsigned long)vcpu->run);
240 fail:
241 return r;
242 }
243 EXPORT_SYMBOL_GPL(kvm_vcpu_init);
244
245 void kvm_vcpu_uninit(struct kvm_vcpu *vcpu)
246 {
247 put_pid(vcpu->pid);
248 kvm_arch_vcpu_uninit(vcpu);
249 free_page((unsigned long)vcpu->run);
250 }
251 EXPORT_SYMBOL_GPL(kvm_vcpu_uninit);
252
253 #if defined(CONFIG_MMU_NOTIFIER) && defined(KVM_ARCH_WANT_MMU_NOTIFIER)
254 static inline struct kvm *mmu_notifier_to_kvm(struct mmu_notifier *mn)
255 {
256 return container_of(mn, struct kvm, mmu_notifier);
257 }
258
259 static void kvm_mmu_notifier_invalidate_page(struct mmu_notifier *mn,
260 struct mm_struct *mm,
261 unsigned long address)
262 {
263 struct kvm *kvm = mmu_notifier_to_kvm(mn);
264 int need_tlb_flush, idx;
265
266 /*
267 * When ->invalidate_page runs, the linux pte has been zapped
268 * already but the page is still allocated until
269 * ->invalidate_page returns. So if we increase the sequence
270 * here the kvm page fault will notice if the spte can't be
271 * established because the page is going to be freed. If
272 * instead the kvm page fault establishes the spte before
273 * ->invalidate_page runs, kvm_unmap_hva will release it
274 * before returning.
275 *
276 * The sequence increase only need to be seen at spin_unlock
277 * time, and not at spin_lock time.
278 *
279 * Increasing the sequence after the spin_unlock would be
280 * unsafe because the kvm page fault could then establish the
281 * pte after kvm_unmap_hva returned, without noticing the page
282 * is going to be freed.
283 */
284 idx = srcu_read_lock(&kvm->srcu);
285 spin_lock(&kvm->mmu_lock);
286 kvm->mmu_notifier_seq++;
287 need_tlb_flush = kvm_unmap_hva(kvm, address) | kvm->tlbs_dirty;
288 spin_unlock(&kvm->mmu_lock);
289 srcu_read_unlock(&kvm->srcu, idx);
290
291 /* we've to flush the tlb before the pages can be freed */
292 if (need_tlb_flush)
293 kvm_flush_remote_tlbs(kvm);
294
295 }
296
297 static void kvm_mmu_notifier_change_pte(struct mmu_notifier *mn,
298 struct mm_struct *mm,
299 unsigned long address,
300 pte_t pte)
301 {
302 struct kvm *kvm = mmu_notifier_to_kvm(mn);
303 int idx;
304
305 idx = srcu_read_lock(&kvm->srcu);
306 spin_lock(&kvm->mmu_lock);
307 kvm->mmu_notifier_seq++;
308 kvm_set_spte_hva(kvm, address, pte);
309 spin_unlock(&kvm->mmu_lock);
310 srcu_read_unlock(&kvm->srcu, idx);
311 }
312
313 static void kvm_mmu_notifier_invalidate_range_start(struct mmu_notifier *mn,
314 struct mm_struct *mm,
315 unsigned long start,
316 unsigned long end)
317 {
318 struct kvm *kvm = mmu_notifier_to_kvm(mn);
319 int need_tlb_flush = 0, idx;
320
321 idx = srcu_read_lock(&kvm->srcu);
322 spin_lock(&kvm->mmu_lock);
323 /*
324 * The count increase must become visible at unlock time as no
325 * spte can be established without taking the mmu_lock and
326 * count is also read inside the mmu_lock critical section.
327 */
328 kvm->mmu_notifier_count++;
329 for (; start < end; start += PAGE_SIZE)
330 need_tlb_flush |= kvm_unmap_hva(kvm, start);
331 need_tlb_flush |= kvm->tlbs_dirty;
332 spin_unlock(&kvm->mmu_lock);
333 srcu_read_unlock(&kvm->srcu, idx);
334
335 /* we've to flush the tlb before the pages can be freed */
336 if (need_tlb_flush)
337 kvm_flush_remote_tlbs(kvm);
338 }
339
340 static void kvm_mmu_notifier_invalidate_range_end(struct mmu_notifier *mn,
341 struct mm_struct *mm,
342 unsigned long start,
343 unsigned long end)
344 {
345 struct kvm *kvm = mmu_notifier_to_kvm(mn);
346
347 spin_lock(&kvm->mmu_lock);
348 /*
349 * This sequence increase will notify the kvm page fault that
350 * the page that is going to be mapped in the spte could have
351 * been freed.
352 */
353 kvm->mmu_notifier_seq++;
354 /*
355 * The above sequence increase must be visible before the
356 * below count decrease but both values are read by the kvm
357 * page fault under mmu_lock spinlock so we don't need to add
358 * a smb_wmb() here in between the two.
359 */
360 kvm->mmu_notifier_count--;
361 spin_unlock(&kvm->mmu_lock);
362
363 BUG_ON(kvm->mmu_notifier_count < 0);
364 }
365
366 static int kvm_mmu_notifier_clear_flush_young(struct mmu_notifier *mn,
367 struct mm_struct *mm,
368 unsigned long address)
369 {
370 struct kvm *kvm = mmu_notifier_to_kvm(mn);
371 int young, idx;
372
373 idx = srcu_read_lock(&kvm->srcu);
374 spin_lock(&kvm->mmu_lock);
375 young = kvm_age_hva(kvm, address);
376 spin_unlock(&kvm->mmu_lock);
377 srcu_read_unlock(&kvm->srcu, idx);
378
379 if (young)
380 kvm_flush_remote_tlbs(kvm);
381
382 return young;
383 }
384
385 static int kvm_mmu_notifier_test_young(struct mmu_notifier *mn,
386 struct mm_struct *mm,
387 unsigned long address)
388 {
389 struct kvm *kvm = mmu_notifier_to_kvm(mn);
390 int young, idx;
391
392 idx = srcu_read_lock(&kvm->srcu);
393 spin_lock(&kvm->mmu_lock);
394 young = kvm_test_age_hva(kvm, address);
395 spin_unlock(&kvm->mmu_lock);
396 srcu_read_unlock(&kvm->srcu, idx);
397
398 return young;
399 }
400
401 static void kvm_mmu_notifier_release(struct mmu_notifier *mn,
402 struct mm_struct *mm)
403 {
404 struct kvm *kvm = mmu_notifier_to_kvm(mn);
405 int idx;
406
407 idx = srcu_read_lock(&kvm->srcu);
408 kvm_arch_flush_shadow(kvm);
409 srcu_read_unlock(&kvm->srcu, idx);
410 }
411
412 static const struct mmu_notifier_ops kvm_mmu_notifier_ops = {
413 .invalidate_page = kvm_mmu_notifier_invalidate_page,
414 .invalidate_range_start = kvm_mmu_notifier_invalidate_range_start,
415 .invalidate_range_end = kvm_mmu_notifier_invalidate_range_end,
416 .clear_flush_young = kvm_mmu_notifier_clear_flush_young,
417 .test_young = kvm_mmu_notifier_test_young,
418 .change_pte = kvm_mmu_notifier_change_pte,
419 .release = kvm_mmu_notifier_release,
420 };
421
422 static int kvm_init_mmu_notifier(struct kvm *kvm)
423 {
424 kvm->mmu_notifier.ops = &kvm_mmu_notifier_ops;
425 return mmu_notifier_register(&kvm->mmu_notifier, current->mm);
426 }
427
428 #else /* !(CONFIG_MMU_NOTIFIER && KVM_ARCH_WANT_MMU_NOTIFIER) */
429
430 static int kvm_init_mmu_notifier(struct kvm *kvm)
431 {
432 return 0;
433 }
434
435 #endif /* CONFIG_MMU_NOTIFIER && KVM_ARCH_WANT_MMU_NOTIFIER */
436
437 static struct kvm *kvm_create_vm(void)
438 {
439 int r, i;
440 struct kvm *kvm = kvm_arch_alloc_vm();
441
442 if (!kvm)
443 return ERR_PTR(-ENOMEM);
444
445 r = kvm_arch_init_vm(kvm);
446 if (r)
447 goto out_err_nodisable;
448
449 r = hardware_enable_all();
450 if (r)
451 goto out_err_nodisable;
452
453 #ifdef CONFIG_HAVE_KVM_IRQCHIP
454 INIT_HLIST_HEAD(&kvm->mask_notifier_list);
455 INIT_HLIST_HEAD(&kvm->irq_ack_notifier_list);
456 #endif
457
458 r = -ENOMEM;
459 kvm->memslots = kzalloc(sizeof(struct kvm_memslots), GFP_KERNEL);
460 if (!kvm->memslots)
461 goto out_err_nosrcu;
462 if (init_srcu_struct(&kvm->srcu))
463 goto out_err_nosrcu;
464 for (i = 0; i < KVM_NR_BUSES; i++) {
465 kvm->buses[i] = kzalloc(sizeof(struct kvm_io_bus),
466 GFP_KERNEL);
467 if (!kvm->buses[i])
468 goto out_err;
469 }
470
471 spin_lock_init(&kvm->mmu_lock);
472 kvm->mm = current->mm;
473 atomic_inc(&kvm->mm->mm_count);
474 kvm_eventfd_init(kvm);
475 mutex_init(&kvm->lock);
476 mutex_init(&kvm->irq_lock);
477 mutex_init(&kvm->slots_lock);
478 atomic_set(&kvm->users_count, 1);
479
480 r = kvm_init_mmu_notifier(kvm);
481 if (r)
482 goto out_err;
483
484 raw_spin_lock(&kvm_lock);
485 list_add(&kvm->vm_list, &vm_list);
486 raw_spin_unlock(&kvm_lock);
487
488 return kvm;
489
490 out_err:
491 cleanup_srcu_struct(&kvm->srcu);
492 out_err_nosrcu:
493 hardware_disable_all();
494 out_err_nodisable:
495 for (i = 0; i < KVM_NR_BUSES; i++)
496 kfree(kvm->buses[i]);
497 kfree(kvm->memslots);
498 kvm_arch_free_vm(kvm);
499 return ERR_PTR(r);
500 }
501
502 static void kvm_destroy_dirty_bitmap(struct kvm_memory_slot *memslot)
503 {
504 if (!memslot->dirty_bitmap)
505 return;
506
507 if (2 * kvm_dirty_bitmap_bytes(memslot) > PAGE_SIZE)
508 vfree(memslot->dirty_bitmap_head);
509 else
510 kfree(memslot->dirty_bitmap_head);
511
512 memslot->dirty_bitmap = NULL;
513 memslot->dirty_bitmap_head = NULL;
514 }
515
516 /*
517 * Free any memory in @free but not in @dont.
518 */
519 static void kvm_free_physmem_slot(struct kvm_memory_slot *free,
520 struct kvm_memory_slot *dont)
521 {
522 int i;
523
524 if (!dont || free->rmap != dont->rmap)
525 vfree(free->rmap);
526
527 if (!dont || free->dirty_bitmap != dont->dirty_bitmap)
528 kvm_destroy_dirty_bitmap(free);
529
530
531 for (i = 0; i < KVM_NR_PAGE_SIZES - 1; ++i) {
532 if (!dont || free->lpage_info[i] != dont->lpage_info[i]) {
533 vfree(free->lpage_info[i]);
534 free->lpage_info[i] = NULL;
535 }
536 }
537
538 free->npages = 0;
539 free->rmap = NULL;
540 }
541
542 void kvm_free_physmem(struct kvm *kvm)
543 {
544 int i;
545 struct kvm_memslots *slots = kvm->memslots;
546
547 for (i = 0; i < slots->nmemslots; ++i)
548 kvm_free_physmem_slot(&slots->memslots[i], NULL);
549
550 kfree(kvm->memslots);
551 }
552
553 static void kvm_destroy_vm(struct kvm *kvm)
554 {
555 int i;
556 struct mm_struct *mm = kvm->mm;
557
558 kvm_arch_sync_events(kvm);
559 raw_spin_lock(&kvm_lock);
560 list_del(&kvm->vm_list);
561 raw_spin_unlock(&kvm_lock);
562 kvm_free_irq_routing(kvm);
563 for (i = 0; i < KVM_NR_BUSES; i++)
564 kvm_io_bus_destroy(kvm->buses[i]);
565 kvm_coalesced_mmio_free(kvm);
566 #if defined(CONFIG_MMU_NOTIFIER) && defined(KVM_ARCH_WANT_MMU_NOTIFIER)
567 mmu_notifier_unregister(&kvm->mmu_notifier, kvm->mm);
568 #else
569 kvm_arch_flush_shadow(kvm);
570 #endif
571 kvm_arch_destroy_vm(kvm);
572 kvm_free_physmem(kvm);
573 cleanup_srcu_struct(&kvm->srcu);
574 kvm_arch_free_vm(kvm);
575 hardware_disable_all();
576 mmdrop(mm);
577 }
578
579 void kvm_get_kvm(struct kvm *kvm)
580 {
581 atomic_inc(&kvm->users_count);
582 }
583 EXPORT_SYMBOL_GPL(kvm_get_kvm);
584
585 void kvm_put_kvm(struct kvm *kvm)
586 {
587 if (atomic_dec_and_test(&kvm->users_count))
588 kvm_destroy_vm(kvm);
589 }
590 EXPORT_SYMBOL_GPL(kvm_put_kvm);
591
592
593 static int kvm_vm_release(struct inode *inode, struct file *filp)
594 {
595 struct kvm *kvm = filp->private_data;
596
597 kvm_irqfd_release(kvm);
598
599 kvm_put_kvm(kvm);
600 return 0;
601 }
602
603 #ifndef CONFIG_S390
604 /*
605 * Allocation size is twice as large as the actual dirty bitmap size.
606 * This makes it possible to do double buffering: see x86's
607 * kvm_vm_ioctl_get_dirty_log().
608 */
609 static int kvm_create_dirty_bitmap(struct kvm_memory_slot *memslot)
610 {
611 unsigned long dirty_bytes = 2 * kvm_dirty_bitmap_bytes(memslot);
612
613 if (dirty_bytes > PAGE_SIZE)
614 memslot->dirty_bitmap = vzalloc(dirty_bytes);
615 else
616 memslot->dirty_bitmap = kzalloc(dirty_bytes, GFP_KERNEL);
617
618 if (!memslot->dirty_bitmap)
619 return -ENOMEM;
620
621 memslot->dirty_bitmap_head = memslot->dirty_bitmap;
622 return 0;
623 }
624 #endif /* !CONFIG_S390 */
625
626 /*
627 * Allocate some memory and give it an address in the guest physical address
628 * space.
629 *
630 * Discontiguous memory is allowed, mostly for framebuffers.
631 *
632 * Must be called holding mmap_sem for write.
633 */
634 int __kvm_set_memory_region(struct kvm *kvm,
635 struct kvm_userspace_memory_region *mem,
636 int user_alloc)
637 {
638 int r;
639 gfn_t base_gfn;
640 unsigned long npages;
641 unsigned long i;
642 struct kvm_memory_slot *memslot;
643 struct kvm_memory_slot old, new;
644 struct kvm_memslots *slots, *old_memslots;
645
646 r = -EINVAL;
647 /* General sanity checks */
648 if (mem->memory_size & (PAGE_SIZE - 1))
649 goto out;
650 if (mem->guest_phys_addr & (PAGE_SIZE - 1))
651 goto out;
652 /* We can read the guest memory with __xxx_user() later on. */
653 if (user_alloc &&
654 ((mem->userspace_addr & (PAGE_SIZE - 1)) ||
655 !access_ok(VERIFY_WRITE,
656 (void __user *)(unsigned long)mem->userspace_addr,
657 mem->memory_size)))
658 goto out;
659 if (mem->slot >= KVM_MEMORY_SLOTS + KVM_PRIVATE_MEM_SLOTS)
660 goto out;
661 if (mem->guest_phys_addr + mem->memory_size < mem->guest_phys_addr)
662 goto out;
663
664 memslot = &kvm->memslots->memslots[mem->slot];
665 base_gfn = mem->guest_phys_addr >> PAGE_SHIFT;
666 npages = mem->memory_size >> PAGE_SHIFT;
667
668 r = -EINVAL;
669 if (npages > KVM_MEM_MAX_NR_PAGES)
670 goto out;
671
672 if (!npages)
673 mem->flags &= ~KVM_MEM_LOG_DIRTY_PAGES;
674
675 new = old = *memslot;
676
677 new.id = mem->slot;
678 new.base_gfn = base_gfn;
679 new.npages = npages;
680 new.flags = mem->flags;
681
682 /* Disallow changing a memory slot's size. */
683 r = -EINVAL;
684 if (npages && old.npages && npages != old.npages)
685 goto out_free;
686
687 /* Check for overlaps */
688 r = -EEXIST;
689 for (i = 0; i < KVM_MEMORY_SLOTS; ++i) {
690 struct kvm_memory_slot *s = &kvm->memslots->memslots[i];
691
692 if (s == memslot || !s->npages)
693 continue;
694 if (!((base_gfn + npages <= s->base_gfn) ||
695 (base_gfn >= s->base_gfn + s->npages)))
696 goto out_free;
697 }
698
699 /* Free page dirty bitmap if unneeded */
700 if (!(new.flags & KVM_MEM_LOG_DIRTY_PAGES))
701 new.dirty_bitmap = NULL;
702
703 r = -ENOMEM;
704
705 /* Allocate if a slot is being created */
706 #ifndef CONFIG_S390
707 if (npages && !new.rmap) {
708 new.rmap = vzalloc(npages * sizeof(*new.rmap));
709
710 if (!new.rmap)
711 goto out_free;
712
713 new.user_alloc = user_alloc;
714 new.userspace_addr = mem->userspace_addr;
715 }
716 if (!npages)
717 goto skip_lpage;
718
719 for (i = 0; i < KVM_NR_PAGE_SIZES - 1; ++i) {
720 unsigned long ugfn;
721 unsigned long j;
722 int lpages;
723 int level = i + 2;
724
725 /* Avoid unused variable warning if no large pages */
726 (void)level;
727
728 if (new.lpage_info[i])
729 continue;
730
731 lpages = 1 + ((base_gfn + npages - 1)
732 >> KVM_HPAGE_GFN_SHIFT(level));
733 lpages -= base_gfn >> KVM_HPAGE_GFN_SHIFT(level);
734
735 new.lpage_info[i] = vzalloc(lpages * sizeof(*new.lpage_info[i]));
736
737 if (!new.lpage_info[i])
738 goto out_free;
739
740 if (base_gfn & (KVM_PAGES_PER_HPAGE(level) - 1))
741 new.lpage_info[i][0].write_count = 1;
742 if ((base_gfn+npages) & (KVM_PAGES_PER_HPAGE(level) - 1))
743 new.lpage_info[i][lpages - 1].write_count = 1;
744 ugfn = new.userspace_addr >> PAGE_SHIFT;
745 /*
746 * If the gfn and userspace address are not aligned wrt each
747 * other, or if explicitly asked to, disable large page
748 * support for this slot
749 */
750 if ((base_gfn ^ ugfn) & (KVM_PAGES_PER_HPAGE(level) - 1) ||
751 !largepages_enabled)
752 for (j = 0; j < lpages; ++j)
753 new.lpage_info[i][j].write_count = 1;
754 }
755
756 skip_lpage:
757
758 /* Allocate page dirty bitmap if needed */
759 if ((new.flags & KVM_MEM_LOG_DIRTY_PAGES) && !new.dirty_bitmap) {
760 if (kvm_create_dirty_bitmap(&new) < 0)
761 goto out_free;
762 /* destroy any largepage mappings for dirty tracking */
763 }
764 #else /* not defined CONFIG_S390 */
765 new.user_alloc = user_alloc;
766 if (user_alloc)
767 new.userspace_addr = mem->userspace_addr;
768 #endif /* not defined CONFIG_S390 */
769
770 if (!npages) {
771 r = -ENOMEM;
772 slots = kzalloc(sizeof(struct kvm_memslots), GFP_KERNEL);
773 if (!slots)
774 goto out_free;
775 memcpy(slots, kvm->memslots, sizeof(struct kvm_memslots));
776 if (mem->slot >= slots->nmemslots)
777 slots->nmemslots = mem->slot + 1;
778 slots->generation++;
779 slots->memslots[mem->slot].flags |= KVM_MEMSLOT_INVALID;
780
781 old_memslots = kvm->memslots;
782 rcu_assign_pointer(kvm->memslots, slots);
783 synchronize_srcu_expedited(&kvm->srcu);
784 /* From this point no new shadow pages pointing to a deleted
785 * memslot will be created.
786 *
787 * validation of sp->gfn happens in:
788 * - gfn_to_hva (kvm_read_guest, gfn_to_pfn)
789 * - kvm_is_visible_gfn (mmu_check_roots)
790 */
791 kvm_arch_flush_shadow(kvm);
792 kfree(old_memslots);
793 }
794
795 r = kvm_arch_prepare_memory_region(kvm, &new, old, mem, user_alloc);
796 if (r)
797 goto out_free;
798
799 /* map the pages in iommu page table */
800 if (npages) {
801 r = kvm_iommu_map_pages(kvm, &new);
802 if (r)
803 goto out_free;
804 }
805
806 r = -ENOMEM;
807 slots = kzalloc(sizeof(struct kvm_memslots), GFP_KERNEL);
808 if (!slots)
809 goto out_free;
810 memcpy(slots, kvm->memslots, sizeof(struct kvm_memslots));
811 if (mem->slot >= slots->nmemslots)
812 slots->nmemslots = mem->slot + 1;
813 slots->generation++;
814
815 /* actual memory is freed via old in kvm_free_physmem_slot below */
816 if (!npages) {
817 new.rmap = NULL;
818 new.dirty_bitmap = NULL;
819 for (i = 0; i < KVM_NR_PAGE_SIZES - 1; ++i)
820 new.lpage_info[i] = NULL;
821 }
822
823 slots->memslots[mem->slot] = new;
824 old_memslots = kvm->memslots;
825 rcu_assign_pointer(kvm->memslots, slots);
826 synchronize_srcu_expedited(&kvm->srcu);
827
828 kvm_arch_commit_memory_region(kvm, mem, old, user_alloc);
829
830 kvm_free_physmem_slot(&old, &new);
831 kfree(old_memslots);
832
833 return 0;
834
835 out_free:
836 kvm_free_physmem_slot(&new, &old);
837 out:
838 return r;
839
840 }
841 EXPORT_SYMBOL_GPL(__kvm_set_memory_region);
842
843 int kvm_set_memory_region(struct kvm *kvm,
844 struct kvm_userspace_memory_region *mem,
845 int user_alloc)
846 {
847 int r;
848
849 mutex_lock(&kvm->slots_lock);
850 r = __kvm_set_memory_region(kvm, mem, user_alloc);
851 mutex_unlock(&kvm->slots_lock);
852 return r;
853 }
854 EXPORT_SYMBOL_GPL(kvm_set_memory_region);
855
856 int kvm_vm_ioctl_set_memory_region(struct kvm *kvm,
857 struct
858 kvm_userspace_memory_region *mem,
859 int user_alloc)
860 {
861 if (mem->slot >= KVM_MEMORY_SLOTS)
862 return -EINVAL;
863 return kvm_set_memory_region(kvm, mem, user_alloc);
864 }
865
866 int kvm_get_dirty_log(struct kvm *kvm,
867 struct kvm_dirty_log *log, int *is_dirty)
868 {
869 struct kvm_memory_slot *memslot;
870 int r, i;
871 unsigned long n;
872 unsigned long any = 0;
873
874 r = -EINVAL;
875 if (log->slot >= KVM_MEMORY_SLOTS)
876 goto out;
877
878 memslot = &kvm->memslots->memslots[log->slot];
879 r = -ENOENT;
880 if (!memslot->dirty_bitmap)
881 goto out;
882
883 n = kvm_dirty_bitmap_bytes(memslot);
884
885 for (i = 0; !any && i < n/sizeof(long); ++i)
886 any = memslot->dirty_bitmap[i];
887
888 r = -EFAULT;
889 if (copy_to_user(log->dirty_bitmap, memslot->dirty_bitmap, n))
890 goto out;
891
892 if (any)
893 *is_dirty = 1;
894
895 r = 0;
896 out:
897 return r;
898 }
899
900 void kvm_disable_largepages(void)
901 {
902 largepages_enabled = false;
903 }
904 EXPORT_SYMBOL_GPL(kvm_disable_largepages);
905
906 int is_error_page(struct page *page)
907 {
908 return page == bad_page || page == hwpoison_page || page == fault_page;
909 }
910 EXPORT_SYMBOL_GPL(is_error_page);
911
912 int is_error_pfn(pfn_t pfn)
913 {
914 return pfn == bad_pfn || pfn == hwpoison_pfn || pfn == fault_pfn;
915 }
916 EXPORT_SYMBOL_GPL(is_error_pfn);
917
918 int is_hwpoison_pfn(pfn_t pfn)
919 {
920 return pfn == hwpoison_pfn;
921 }
922 EXPORT_SYMBOL_GPL(is_hwpoison_pfn);
923
924 int is_fault_pfn(pfn_t pfn)
925 {
926 return pfn == fault_pfn;
927 }
928 EXPORT_SYMBOL_GPL(is_fault_pfn);
929
930 static inline unsigned long bad_hva(void)
931 {
932 return PAGE_OFFSET;
933 }
934
935 int kvm_is_error_hva(unsigned long addr)
936 {
937 return addr == bad_hva();
938 }
939 EXPORT_SYMBOL_GPL(kvm_is_error_hva);
940
941 static struct kvm_memory_slot *__gfn_to_memslot(struct kvm_memslots *slots,
942 gfn_t gfn)
943 {
944 int i;
945
946 for (i = 0; i < slots->nmemslots; ++i) {
947 struct kvm_memory_slot *memslot = &slots->memslots[i];
948
949 if (gfn >= memslot->base_gfn
950 && gfn < memslot->base_gfn + memslot->npages)
951 return memslot;
952 }
953 return NULL;
954 }
955
956 struct kvm_memory_slot *gfn_to_memslot(struct kvm *kvm, gfn_t gfn)
957 {
958 return __gfn_to_memslot(kvm_memslots(kvm), gfn);
959 }
960 EXPORT_SYMBOL_GPL(gfn_to_memslot);
961
962 int kvm_is_visible_gfn(struct kvm *kvm, gfn_t gfn)
963 {
964 int i;
965 struct kvm_memslots *slots = kvm_memslots(kvm);
966
967 for (i = 0; i < KVM_MEMORY_SLOTS; ++i) {
968 struct kvm_memory_slot *memslot = &slots->memslots[i];
969
970 if (memslot->flags & KVM_MEMSLOT_INVALID)
971 continue;
972
973 if (gfn >= memslot->base_gfn
974 && gfn < memslot->base_gfn + memslot->npages)
975 return 1;
976 }
977 return 0;
978 }
979 EXPORT_SYMBOL_GPL(kvm_is_visible_gfn);
980
981 unsigned long kvm_host_page_size(struct kvm *kvm, gfn_t gfn)
982 {
983 struct vm_area_struct *vma;
984 unsigned long addr, size;
985
986 size = PAGE_SIZE;
987
988 addr = gfn_to_hva(kvm, gfn);
989 if (kvm_is_error_hva(addr))
990 return PAGE_SIZE;
991
992 down_read(&current->mm->mmap_sem);
993 vma = find_vma(current->mm, addr);
994 if (!vma)
995 goto out;
996
997 size = vma_kernel_pagesize(vma);
998
999 out:
1000 up_read(&current->mm->mmap_sem);
1001
1002 return size;
1003 }
1004
1005 static unsigned long gfn_to_hva_many(struct kvm_memory_slot *slot, gfn_t gfn,
1006 gfn_t *nr_pages)
1007 {
1008 if (!slot || slot->flags & KVM_MEMSLOT_INVALID)
1009 return bad_hva();
1010
1011 if (nr_pages)
1012 *nr_pages = slot->npages - (gfn - slot->base_gfn);
1013
1014 return gfn_to_hva_memslot(slot, gfn);
1015 }
1016
1017 unsigned long gfn_to_hva(struct kvm *kvm, gfn_t gfn)
1018 {
1019 return gfn_to_hva_many(gfn_to_memslot(kvm, gfn), gfn, NULL);
1020 }
1021 EXPORT_SYMBOL_GPL(gfn_to_hva);
1022
1023 static pfn_t get_fault_pfn(void)
1024 {
1025 get_page(fault_page);
1026 return fault_pfn;
1027 }
1028
1029 int get_user_page_nowait(struct task_struct *tsk, struct mm_struct *mm,
1030 unsigned long start, int write, struct page **page)
1031 {
1032 int flags = FOLL_TOUCH | FOLL_NOWAIT | FOLL_HWPOISON | FOLL_GET;
1033
1034 if (write)
1035 flags |= FOLL_WRITE;
1036
1037 return __get_user_pages(tsk, mm, start, 1, flags, page, NULL, NULL);
1038 }
1039
1040 static inline int check_user_page_hwpoison(unsigned long addr)
1041 {
1042 int rc, flags = FOLL_TOUCH | FOLL_HWPOISON | FOLL_WRITE;
1043
1044 rc = __get_user_pages(current, current->mm, addr, 1,
1045 flags, NULL, NULL, NULL);
1046 return rc == -EHWPOISON;
1047 }
1048
1049 static pfn_t hva_to_pfn(struct kvm *kvm, unsigned long addr, bool atomic,
1050 bool *async, bool write_fault, bool *writable)
1051 {
1052 struct page *page[1];
1053 int npages = 0;
1054 pfn_t pfn;
1055
1056 /* we can do it either atomically or asynchronously, not both */
1057 BUG_ON(atomic && async);
1058
1059 BUG_ON(!write_fault && !writable);
1060
1061 if (writable)
1062 *writable = true;
1063
1064 if (atomic || async)
1065 npages = __get_user_pages_fast(addr, 1, 1, page);
1066
1067 if (unlikely(npages != 1) && !atomic) {
1068 might_sleep();
1069
1070 if (writable)
1071 *writable = write_fault;
1072
1073 if (async) {
1074 down_read(&current->mm->mmap_sem);
1075 npages = get_user_page_nowait(current, current->mm,
1076 addr, write_fault, page);
1077 up_read(&current->mm->mmap_sem);
1078 } else
1079 npages = get_user_pages_fast(addr, 1, write_fault,
1080 page);
1081
1082 /* map read fault as writable if possible */
1083 if (unlikely(!write_fault) && npages == 1) {
1084 struct page *wpage[1];
1085
1086 npages = __get_user_pages_fast(addr, 1, 1, wpage);
1087 if (npages == 1) {
1088 *writable = true;
1089 put_page(page[0]);
1090 page[0] = wpage[0];
1091 }
1092 npages = 1;
1093 }
1094 }
1095
1096 if (unlikely(npages != 1)) {
1097 struct vm_area_struct *vma;
1098
1099 if (atomic)
1100 return get_fault_pfn();
1101
1102 down_read(&current->mm->mmap_sem);
1103 if (npages == -EHWPOISON ||
1104 (!async && check_user_page_hwpoison(addr))) {
1105 up_read(&current->mm->mmap_sem);
1106 get_page(hwpoison_page);
1107 return page_to_pfn(hwpoison_page);
1108 }
1109
1110 vma = find_vma_intersection(current->mm, addr, addr+1);
1111
1112 if (vma == NULL)
1113 pfn = get_fault_pfn();
1114 else if ((vma->vm_flags & VM_PFNMAP)) {
1115 pfn = ((addr - vma->vm_start) >> PAGE_SHIFT) +
1116 vma->vm_pgoff;
1117 BUG_ON(!kvm_is_mmio_pfn(pfn));
1118 } else {
1119 if (async && (vma->vm_flags & VM_WRITE))
1120 *async = true;
1121 pfn = get_fault_pfn();
1122 }
1123 up_read(&current->mm->mmap_sem);
1124 } else
1125 pfn = page_to_pfn(page[0]);
1126
1127 return pfn;
1128 }
1129
1130 pfn_t hva_to_pfn_atomic(struct kvm *kvm, unsigned long addr)
1131 {
1132 return hva_to_pfn(kvm, addr, true, NULL, true, NULL);
1133 }
1134 EXPORT_SYMBOL_GPL(hva_to_pfn_atomic);
1135
1136 static pfn_t __gfn_to_pfn(struct kvm *kvm, gfn_t gfn, bool atomic, bool *async,
1137 bool write_fault, bool *writable)
1138 {
1139 unsigned long addr;
1140
1141 if (async)
1142 *async = false;
1143
1144 addr = gfn_to_hva(kvm, gfn);
1145 if (kvm_is_error_hva(addr)) {
1146 get_page(bad_page);
1147 return page_to_pfn(bad_page);
1148 }
1149
1150 return hva_to_pfn(kvm, addr, atomic, async, write_fault, writable);
1151 }
1152
1153 pfn_t gfn_to_pfn_atomic(struct kvm *kvm, gfn_t gfn)
1154 {
1155 return __gfn_to_pfn(kvm, gfn, true, NULL, true, NULL);
1156 }
1157 EXPORT_SYMBOL_GPL(gfn_to_pfn_atomic);
1158
1159 pfn_t gfn_to_pfn_async(struct kvm *kvm, gfn_t gfn, bool *async,
1160 bool write_fault, bool *writable)
1161 {
1162 return __gfn_to_pfn(kvm, gfn, false, async, write_fault, writable);
1163 }
1164 EXPORT_SYMBOL_GPL(gfn_to_pfn_async);
1165
1166 pfn_t gfn_to_pfn(struct kvm *kvm, gfn_t gfn)
1167 {
1168 return __gfn_to_pfn(kvm, gfn, false, NULL, true, NULL);
1169 }
1170 EXPORT_SYMBOL_GPL(gfn_to_pfn);
1171
1172 pfn_t gfn_to_pfn_prot(struct kvm *kvm, gfn_t gfn, bool write_fault,
1173 bool *writable)
1174 {
1175 return __gfn_to_pfn(kvm, gfn, false, NULL, write_fault, writable);
1176 }
1177 EXPORT_SYMBOL_GPL(gfn_to_pfn_prot);
1178
1179 pfn_t gfn_to_pfn_memslot(struct kvm *kvm,
1180 struct kvm_memory_slot *slot, gfn_t gfn)
1181 {
1182 unsigned long addr = gfn_to_hva_memslot(slot, gfn);
1183 return hva_to_pfn(kvm, addr, false, NULL, true, NULL);
1184 }
1185
1186 int gfn_to_page_many_atomic(struct kvm *kvm, gfn_t gfn, struct page **pages,
1187 int nr_pages)
1188 {
1189 unsigned long addr;
1190 gfn_t entry;
1191
1192 addr = gfn_to_hva_many(gfn_to_memslot(kvm, gfn), gfn, &entry);
1193 if (kvm_is_error_hva(addr))
1194 return -1;
1195
1196 if (entry < nr_pages)
1197 return 0;
1198
1199 return __get_user_pages_fast(addr, nr_pages, 1, pages);
1200 }
1201 EXPORT_SYMBOL_GPL(gfn_to_page_many_atomic);
1202
1203 struct page *gfn_to_page(struct kvm *kvm, gfn_t gfn)
1204 {
1205 pfn_t pfn;
1206
1207 pfn = gfn_to_pfn(kvm, gfn);
1208 if (!kvm_is_mmio_pfn(pfn))
1209 return pfn_to_page(pfn);
1210
1211 WARN_ON(kvm_is_mmio_pfn(pfn));
1212
1213 get_page(bad_page);
1214 return bad_page;
1215 }
1216
1217 EXPORT_SYMBOL_GPL(gfn_to_page);
1218
1219 void kvm_release_page_clean(struct page *page)
1220 {
1221 kvm_release_pfn_clean(page_to_pfn(page));
1222 }
1223 EXPORT_SYMBOL_GPL(kvm_release_page_clean);
1224
1225 void kvm_release_pfn_clean(pfn_t pfn)
1226 {
1227 if (!kvm_is_mmio_pfn(pfn))
1228 put_page(pfn_to_page(pfn));
1229 }
1230 EXPORT_SYMBOL_GPL(kvm_release_pfn_clean);
1231
1232 void kvm_release_page_dirty(struct page *page)
1233 {
1234 kvm_release_pfn_dirty(page_to_pfn(page));
1235 }
1236 EXPORT_SYMBOL_GPL(kvm_release_page_dirty);
1237
1238 void kvm_release_pfn_dirty(pfn_t pfn)
1239 {
1240 kvm_set_pfn_dirty(pfn);
1241 kvm_release_pfn_clean(pfn);
1242 }
1243 EXPORT_SYMBOL_GPL(kvm_release_pfn_dirty);
1244
1245 void kvm_set_page_dirty(struct page *page)
1246 {
1247 kvm_set_pfn_dirty(page_to_pfn(page));
1248 }
1249 EXPORT_SYMBOL_GPL(kvm_set_page_dirty);
1250
1251 void kvm_set_pfn_dirty(pfn_t pfn)
1252 {
1253 if (!kvm_is_mmio_pfn(pfn)) {
1254 struct page *page = pfn_to_page(pfn);
1255 if (!PageReserved(page))
1256 SetPageDirty(page);
1257 }
1258 }
1259 EXPORT_SYMBOL_GPL(kvm_set_pfn_dirty);
1260
1261 void kvm_set_pfn_accessed(pfn_t pfn)
1262 {
1263 if (!kvm_is_mmio_pfn(pfn))
1264 mark_page_accessed(pfn_to_page(pfn));
1265 }
1266 EXPORT_SYMBOL_GPL(kvm_set_pfn_accessed);
1267
1268 void kvm_get_pfn(pfn_t pfn)
1269 {
1270 if (!kvm_is_mmio_pfn(pfn))
1271 get_page(pfn_to_page(pfn));
1272 }
1273 EXPORT_SYMBOL_GPL(kvm_get_pfn);
1274
1275 static int next_segment(unsigned long len, int offset)
1276 {
1277 if (len > PAGE_SIZE - offset)
1278 return PAGE_SIZE - offset;
1279 else
1280 return len;
1281 }
1282
1283 int kvm_read_guest_page(struct kvm *kvm, gfn_t gfn, void *data, int offset,
1284 int len)
1285 {
1286 int r;
1287 unsigned long addr;
1288
1289 addr = gfn_to_hva(kvm, gfn);
1290 if (kvm_is_error_hva(addr))
1291 return -EFAULT;
1292 r = __copy_from_user(data, (void __user *)addr + offset, len);
1293 if (r)
1294 return -EFAULT;
1295 return 0;
1296 }
1297 EXPORT_SYMBOL_GPL(kvm_read_guest_page);
1298
1299 int kvm_read_guest(struct kvm *kvm, gpa_t gpa, void *data, unsigned long len)
1300 {
1301 gfn_t gfn = gpa >> PAGE_SHIFT;
1302 int seg;
1303 int offset = offset_in_page(gpa);
1304 int ret;
1305
1306 while ((seg = next_segment(len, offset)) != 0) {
1307 ret = kvm_read_guest_page(kvm, gfn, data, offset, seg);
1308 if (ret < 0)
1309 return ret;
1310 offset = 0;
1311 len -= seg;
1312 data += seg;
1313 ++gfn;
1314 }
1315 return 0;
1316 }
1317 EXPORT_SYMBOL_GPL(kvm_read_guest);
1318
1319 int kvm_read_guest_atomic(struct kvm *kvm, gpa_t gpa, void *data,
1320 unsigned long len)
1321 {
1322 int r;
1323 unsigned long addr;
1324 gfn_t gfn = gpa >> PAGE_SHIFT;
1325 int offset = offset_in_page(gpa);
1326
1327 addr = gfn_to_hva(kvm, gfn);
1328 if (kvm_is_error_hva(addr))
1329 return -EFAULT;
1330 pagefault_disable();
1331 r = __copy_from_user_inatomic(data, (void __user *)addr + offset, len);
1332 pagefault_enable();
1333 if (r)
1334 return -EFAULT;
1335 return 0;
1336 }
1337 EXPORT_SYMBOL(kvm_read_guest_atomic);
1338
1339 int kvm_write_guest_page(struct kvm *kvm, gfn_t gfn, const void *data,
1340 int offset, int len)
1341 {
1342 int r;
1343 unsigned long addr;
1344
1345 addr = gfn_to_hva(kvm, gfn);
1346 if (kvm_is_error_hva(addr))
1347 return -EFAULT;
1348 r = copy_to_user((void __user *)addr + offset, data, len);
1349 if (r)
1350 return -EFAULT;
1351 mark_page_dirty(kvm, gfn);
1352 return 0;
1353 }
1354 EXPORT_SYMBOL_GPL(kvm_write_guest_page);
1355
1356 int kvm_write_guest(struct kvm *kvm, gpa_t gpa, const void *data,
1357 unsigned long len)
1358 {
1359 gfn_t gfn = gpa >> PAGE_SHIFT;
1360 int seg;
1361 int offset = offset_in_page(gpa);
1362 int ret;
1363
1364 while ((seg = next_segment(len, offset)) != 0) {
1365 ret = kvm_write_guest_page(kvm, gfn, data, offset, seg);
1366 if (ret < 0)
1367 return ret;
1368 offset = 0;
1369 len -= seg;
1370 data += seg;
1371 ++gfn;
1372 }
1373 return 0;
1374 }
1375
1376 int kvm_gfn_to_hva_cache_init(struct kvm *kvm, struct gfn_to_hva_cache *ghc,
1377 gpa_t gpa)
1378 {
1379 struct kvm_memslots *slots = kvm_memslots(kvm);
1380 int offset = offset_in_page(gpa);
1381 gfn_t gfn = gpa >> PAGE_SHIFT;
1382
1383 ghc->gpa = gpa;
1384 ghc->generation = slots->generation;
1385 ghc->memslot = __gfn_to_memslot(slots, gfn);
1386 ghc->hva = gfn_to_hva_many(ghc->memslot, gfn, NULL);
1387 if (!kvm_is_error_hva(ghc->hva))
1388 ghc->hva += offset;
1389 else
1390 return -EFAULT;
1391
1392 return 0;
1393 }
1394 EXPORT_SYMBOL_GPL(kvm_gfn_to_hva_cache_init);
1395
1396 int kvm_write_guest_cached(struct kvm *kvm, struct gfn_to_hva_cache *ghc,
1397 void *data, unsigned long len)
1398 {
1399 struct kvm_memslots *slots = kvm_memslots(kvm);
1400 int r;
1401
1402 if (slots->generation != ghc->generation)
1403 kvm_gfn_to_hva_cache_init(kvm, ghc, ghc->gpa);
1404
1405 if (kvm_is_error_hva(ghc->hva))
1406 return -EFAULT;
1407
1408 r = copy_to_user((void __user *)ghc->hva, data, len);
1409 if (r)
1410 return -EFAULT;
1411 mark_page_dirty_in_slot(kvm, ghc->memslot, ghc->gpa >> PAGE_SHIFT);
1412
1413 return 0;
1414 }
1415 EXPORT_SYMBOL_GPL(kvm_write_guest_cached);
1416
1417 int kvm_clear_guest_page(struct kvm *kvm, gfn_t gfn, int offset, int len)
1418 {
1419 return kvm_write_guest_page(kvm, gfn, (const void *) empty_zero_page,
1420 offset, len);
1421 }
1422 EXPORT_SYMBOL_GPL(kvm_clear_guest_page);
1423
1424 int kvm_clear_guest(struct kvm *kvm, gpa_t gpa, unsigned long len)
1425 {
1426 gfn_t gfn = gpa >> PAGE_SHIFT;
1427 int seg;
1428 int offset = offset_in_page(gpa);
1429 int ret;
1430
1431 while ((seg = next_segment(len, offset)) != 0) {
1432 ret = kvm_clear_guest_page(kvm, gfn, offset, seg);
1433 if (ret < 0)
1434 return ret;
1435 offset = 0;
1436 len -= seg;
1437 ++gfn;
1438 }
1439 return 0;
1440 }
1441 EXPORT_SYMBOL_GPL(kvm_clear_guest);
1442
1443 void mark_page_dirty_in_slot(struct kvm *kvm, struct kvm_memory_slot *memslot,
1444 gfn_t gfn)
1445 {
1446 if (memslot && memslot->dirty_bitmap) {
1447 unsigned long rel_gfn = gfn - memslot->base_gfn;
1448
1449 __set_bit_le(rel_gfn, memslot->dirty_bitmap);
1450 }
1451 }
1452
1453 void mark_page_dirty(struct kvm *kvm, gfn_t gfn)
1454 {
1455 struct kvm_memory_slot *memslot;
1456
1457 memslot = gfn_to_memslot(kvm, gfn);
1458 mark_page_dirty_in_slot(kvm, memslot, gfn);
1459 }
1460
1461 /*
1462 * The vCPU has executed a HLT instruction with in-kernel mode enabled.
1463 */
1464 void kvm_vcpu_block(struct kvm_vcpu *vcpu)
1465 {
1466 DEFINE_WAIT(wait);
1467
1468 for (;;) {
1469 prepare_to_wait(&vcpu->wq, &wait, TASK_INTERRUPTIBLE);
1470
1471 if (kvm_arch_vcpu_runnable(vcpu)) {
1472 kvm_make_request(KVM_REQ_UNHALT, vcpu);
1473 break;
1474 }
1475 if (kvm_cpu_has_pending_timer(vcpu))
1476 break;
1477 if (signal_pending(current))
1478 break;
1479
1480 schedule();
1481 }
1482
1483 finish_wait(&vcpu->wq, &wait);
1484 }
1485
1486 void kvm_resched(struct kvm_vcpu *vcpu)
1487 {
1488 if (!need_resched())
1489 return;
1490 cond_resched();
1491 }
1492 EXPORT_SYMBOL_GPL(kvm_resched);
1493
1494 void kvm_vcpu_on_spin(struct kvm_vcpu *me)
1495 {
1496 struct kvm *kvm = me->kvm;
1497 struct kvm_vcpu *vcpu;
1498 int last_boosted_vcpu = me->kvm->last_boosted_vcpu;
1499 int yielded = 0;
1500 int pass;
1501 int i;
1502
1503 /*
1504 * We boost the priority of a VCPU that is runnable but not
1505 * currently running, because it got preempted by something
1506 * else and called schedule in __vcpu_run. Hopefully that
1507 * VCPU is holding the lock that we need and will release it.
1508 * We approximate round-robin by starting at the last boosted VCPU.
1509 */
1510 for (pass = 0; pass < 2 && !yielded; pass++) {
1511 kvm_for_each_vcpu(i, vcpu, kvm) {
1512 struct task_struct *task = NULL;
1513 struct pid *pid;
1514 if (!pass && i < last_boosted_vcpu) {
1515 i = last_boosted_vcpu;
1516 continue;
1517 } else if (pass && i > last_boosted_vcpu)
1518 break;
1519 if (vcpu == me)
1520 continue;
1521 if (waitqueue_active(&vcpu->wq))
1522 continue;
1523 rcu_read_lock();
1524 pid = rcu_dereference(vcpu->pid);
1525 if (pid)
1526 task = get_pid_task(vcpu->pid, PIDTYPE_PID);
1527 rcu_read_unlock();
1528 if (!task)
1529 continue;
1530 if (task->flags & PF_VCPU) {
1531 put_task_struct(task);
1532 continue;
1533 }
1534 if (yield_to(task, 1)) {
1535 put_task_struct(task);
1536 kvm->last_boosted_vcpu = i;
1537 yielded = 1;
1538 break;
1539 }
1540 put_task_struct(task);
1541 }
1542 }
1543 }
1544 EXPORT_SYMBOL_GPL(kvm_vcpu_on_spin);
1545
1546 static int kvm_vcpu_fault(struct vm_area_struct *vma, struct vm_fault *vmf)
1547 {
1548 struct kvm_vcpu *vcpu = vma->vm_file->private_data;
1549 struct page *page;
1550
1551 if (vmf->pgoff == 0)
1552 page = virt_to_page(vcpu->run);
1553 #ifdef CONFIG_X86
1554 else if (vmf->pgoff == KVM_PIO_PAGE_OFFSET)
1555 page = virt_to_page(vcpu->arch.pio_data);
1556 #endif
1557 #ifdef KVM_COALESCED_MMIO_PAGE_OFFSET
1558 else if (vmf->pgoff == KVM_COALESCED_MMIO_PAGE_OFFSET)
1559 page = virt_to_page(vcpu->kvm->coalesced_mmio_ring);
1560 #endif
1561 else
1562 return VM_FAULT_SIGBUS;
1563 get_page(page);
1564 vmf->page = page;
1565 return 0;
1566 }
1567
1568 static const struct vm_operations_struct kvm_vcpu_vm_ops = {
1569 .fault = kvm_vcpu_fault,
1570 };
1571
1572 static int kvm_vcpu_mmap(struct file *file, struct vm_area_struct *vma)
1573 {
1574 vma->vm_ops = &kvm_vcpu_vm_ops;
1575 return 0;
1576 }
1577
1578 static int kvm_vcpu_release(struct inode *inode, struct file *filp)
1579 {
1580 struct kvm_vcpu *vcpu = filp->private_data;
1581
1582 kvm_put_kvm(vcpu->kvm);
1583 return 0;
1584 }
1585
1586 static struct file_operations kvm_vcpu_fops = {
1587 .release = kvm_vcpu_release,
1588 .unlocked_ioctl = kvm_vcpu_ioctl,
1589 .compat_ioctl = kvm_vcpu_ioctl,
1590 .mmap = kvm_vcpu_mmap,
1591 .llseek = noop_llseek,
1592 };
1593
1594 /*
1595 * Allocates an inode for the vcpu.
1596 */
1597 static int create_vcpu_fd(struct kvm_vcpu *vcpu)
1598 {
1599 return anon_inode_getfd("kvm-vcpu", &kvm_vcpu_fops, vcpu, O_RDWR);
1600 }
1601
1602 /*
1603 * Creates some virtual cpus. Good luck creating more than one.
1604 */
1605 static int kvm_vm_ioctl_create_vcpu(struct kvm *kvm, u32 id)
1606 {
1607 int r;
1608 struct kvm_vcpu *vcpu, *v;
1609
1610 vcpu = kvm_arch_vcpu_create(kvm, id);
1611 if (IS_ERR(vcpu))
1612 return PTR_ERR(vcpu);
1613
1614 preempt_notifier_init(&vcpu->preempt_notifier, &kvm_preempt_ops);
1615
1616 r = kvm_arch_vcpu_setup(vcpu);
1617 if (r)
1618 return r;
1619
1620 mutex_lock(&kvm->lock);
1621 if (atomic_read(&kvm->online_vcpus) == KVM_MAX_VCPUS) {
1622 r = -EINVAL;
1623 goto vcpu_destroy;
1624 }
1625
1626 kvm_for_each_vcpu(r, v, kvm)
1627 if (v->vcpu_id == id) {
1628 r = -EEXIST;
1629 goto vcpu_destroy;
1630 }
1631
1632 BUG_ON(kvm->vcpus[atomic_read(&kvm->online_vcpus)]);
1633
1634 /* Now it's all set up, let userspace reach it */
1635 kvm_get_kvm(kvm);
1636 r = create_vcpu_fd(vcpu);
1637 if (r < 0) {
1638 kvm_put_kvm(kvm);
1639 goto vcpu_destroy;
1640 }
1641
1642 kvm->vcpus[atomic_read(&kvm->online_vcpus)] = vcpu;
1643 smp_wmb();
1644 atomic_inc(&kvm->online_vcpus);
1645
1646 #ifdef CONFIG_KVM_APIC_ARCHITECTURE
1647 if (kvm->bsp_vcpu_id == id)
1648 kvm->bsp_vcpu = vcpu;
1649 #endif
1650 mutex_unlock(&kvm->lock);
1651 return r;
1652
1653 vcpu_destroy:
1654 mutex_unlock(&kvm->lock);
1655 kvm_arch_vcpu_destroy(vcpu);
1656 return r;
1657 }
1658
1659 static int kvm_vcpu_ioctl_set_sigmask(struct kvm_vcpu *vcpu, sigset_t *sigset)
1660 {
1661 if (sigset) {
1662 sigdelsetmask(sigset, sigmask(SIGKILL)|sigmask(SIGSTOP));
1663 vcpu->sigset_active = 1;
1664 vcpu->sigset = *sigset;
1665 } else
1666 vcpu->sigset_active = 0;
1667 return 0;
1668 }
1669
1670 static long kvm_vcpu_ioctl(struct file *filp,
1671 unsigned int ioctl, unsigned long arg)
1672 {
1673 struct kvm_vcpu *vcpu = filp->private_data;
1674 void __user *argp = (void __user *)arg;
1675 int r;
1676 struct kvm_fpu *fpu = NULL;
1677 struct kvm_sregs *kvm_sregs = NULL;
1678
1679 if (vcpu->kvm->mm != current->mm)
1680 return -EIO;
1681
1682 #if defined(CONFIG_S390) || defined(CONFIG_PPC)
1683 /*
1684 * Special cases: vcpu ioctls that are asynchronous to vcpu execution,
1685 * so vcpu_load() would break it.
1686 */
1687 if (ioctl == KVM_S390_INTERRUPT || ioctl == KVM_INTERRUPT)
1688 return kvm_arch_vcpu_ioctl(filp, ioctl, arg);
1689 #endif
1690
1691
1692 vcpu_load(vcpu);
1693 switch (ioctl) {
1694 case KVM_RUN:
1695 r = -EINVAL;
1696 if (arg)
1697 goto out;
1698 r = kvm_arch_vcpu_ioctl_run(vcpu, vcpu->run);
1699 trace_kvm_userspace_exit(vcpu->run->exit_reason, r);
1700 break;
1701 case KVM_GET_REGS: {
1702 struct kvm_regs *kvm_regs;
1703
1704 r = -ENOMEM;
1705 kvm_regs = kzalloc(sizeof(struct kvm_regs), GFP_KERNEL);
1706 if (!kvm_regs)
1707 goto out;
1708 r = kvm_arch_vcpu_ioctl_get_regs(vcpu, kvm_regs);
1709 if (r)
1710 goto out_free1;
1711 r = -EFAULT;
1712 if (copy_to_user(argp, kvm_regs, sizeof(struct kvm_regs)))
1713 goto out_free1;
1714 r = 0;
1715 out_free1:
1716 kfree(kvm_regs);
1717 break;
1718 }
1719 case KVM_SET_REGS: {
1720 struct kvm_regs *kvm_regs;
1721
1722 r = -ENOMEM;
1723 kvm_regs = kzalloc(sizeof(struct kvm_regs), GFP_KERNEL);
1724 if (!kvm_regs)
1725 goto out;
1726 r = -EFAULT;
1727 if (copy_from_user(kvm_regs, argp, sizeof(struct kvm_regs)))
1728 goto out_free2;
1729 r = kvm_arch_vcpu_ioctl_set_regs(vcpu, kvm_regs);
1730 if (r)
1731 goto out_free2;
1732 r = 0;
1733 out_free2:
1734 kfree(kvm_regs);
1735 break;
1736 }
1737 case KVM_GET_SREGS: {
1738 kvm_sregs = kzalloc(sizeof(struct kvm_sregs), GFP_KERNEL);
1739 r = -ENOMEM;
1740 if (!kvm_sregs)
1741 goto out;
1742 r = kvm_arch_vcpu_ioctl_get_sregs(vcpu, kvm_sregs);
1743 if (r)
1744 goto out;
1745 r = -EFAULT;
1746 if (copy_to_user(argp, kvm_sregs, sizeof(struct kvm_sregs)))
1747 goto out;
1748 r = 0;
1749 break;
1750 }
1751 case KVM_SET_SREGS: {
1752 kvm_sregs = kmalloc(sizeof(struct kvm_sregs), GFP_KERNEL);
1753 r = -ENOMEM;
1754 if (!kvm_sregs)
1755 goto out;
1756 r = -EFAULT;
1757 if (copy_from_user(kvm_sregs, argp, sizeof(struct kvm_sregs)))
1758 goto out;
1759 r = kvm_arch_vcpu_ioctl_set_sregs(vcpu, kvm_sregs);
1760 if (r)
1761 goto out;
1762 r = 0;
1763 break;
1764 }
1765 case KVM_GET_MP_STATE: {
1766 struct kvm_mp_state mp_state;
1767
1768 r = kvm_arch_vcpu_ioctl_get_mpstate(vcpu, &mp_state);
1769 if (r)
1770 goto out;
1771 r = -EFAULT;
1772 if (copy_to_user(argp, &mp_state, sizeof mp_state))
1773 goto out;
1774 r = 0;
1775 break;
1776 }
1777 case KVM_SET_MP_STATE: {
1778 struct kvm_mp_state mp_state;
1779
1780 r = -EFAULT;
1781 if (copy_from_user(&mp_state, argp, sizeof mp_state))
1782 goto out;
1783 r = kvm_arch_vcpu_ioctl_set_mpstate(vcpu, &mp_state);
1784 if (r)
1785 goto out;
1786 r = 0;
1787 break;
1788 }
1789 case KVM_TRANSLATE: {
1790 struct kvm_translation tr;
1791
1792 r = -EFAULT;
1793 if (copy_from_user(&tr, argp, sizeof tr))
1794 goto out;
1795 r = kvm_arch_vcpu_ioctl_translate(vcpu, &tr);
1796 if (r)
1797 goto out;
1798 r = -EFAULT;
1799 if (copy_to_user(argp, &tr, sizeof tr))
1800 goto out;
1801 r = 0;
1802 break;
1803 }
1804 case KVM_SET_GUEST_DEBUG: {
1805 struct kvm_guest_debug dbg;
1806
1807 r = -EFAULT;
1808 if (copy_from_user(&dbg, argp, sizeof dbg))
1809 goto out;
1810 r = kvm_arch_vcpu_ioctl_set_guest_debug(vcpu, &dbg);
1811 if (r)
1812 goto out;
1813 r = 0;
1814 break;
1815 }
1816 case KVM_SET_SIGNAL_MASK: {
1817 struct kvm_signal_mask __user *sigmask_arg = argp;
1818 struct kvm_signal_mask kvm_sigmask;
1819 sigset_t sigset, *p;
1820
1821 p = NULL;
1822 if (argp) {
1823 r = -EFAULT;
1824 if (copy_from_user(&kvm_sigmask, argp,
1825 sizeof kvm_sigmask))
1826 goto out;
1827 r = -EINVAL;
1828 if (kvm_sigmask.len != sizeof sigset)
1829 goto out;
1830 r = -EFAULT;
1831 if (copy_from_user(&sigset, sigmask_arg->sigset,
1832 sizeof sigset))
1833 goto out;
1834 p = &sigset;
1835 }
1836 r = kvm_vcpu_ioctl_set_sigmask(vcpu, p);
1837 break;
1838 }
1839 case KVM_GET_FPU: {
1840 fpu = kzalloc(sizeof(struct kvm_fpu), GFP_KERNEL);
1841 r = -ENOMEM;
1842 if (!fpu)
1843 goto out;
1844 r = kvm_arch_vcpu_ioctl_get_fpu(vcpu, fpu);
1845 if (r)
1846 goto out;
1847 r = -EFAULT;
1848 if (copy_to_user(argp, fpu, sizeof(struct kvm_fpu)))
1849 goto out;
1850 r = 0;
1851 break;
1852 }
1853 case KVM_SET_FPU: {
1854 fpu = kmalloc(sizeof(struct kvm_fpu), GFP_KERNEL);
1855 r = -ENOMEM;
1856 if (!fpu)
1857 goto out;
1858 r = -EFAULT;
1859 if (copy_from_user(fpu, argp, sizeof(struct kvm_fpu)))
1860 goto out;
1861 r = kvm_arch_vcpu_ioctl_set_fpu(vcpu, fpu);
1862 if (r)
1863 goto out;
1864 r = 0;
1865 break;
1866 }
1867 default:
1868 r = kvm_arch_vcpu_ioctl(filp, ioctl, arg);
1869 }
1870 out:
1871 vcpu_put(vcpu);
1872 kfree(fpu);
1873 kfree(kvm_sregs);
1874 return r;
1875 }
1876
1877 static long kvm_vm_ioctl(struct file *filp,
1878 unsigned int ioctl, unsigned long arg)
1879 {
1880 struct kvm *kvm = filp->private_data;
1881 void __user *argp = (void __user *)arg;
1882 int r;
1883
1884 if (kvm->mm != current->mm)
1885 return -EIO;
1886 switch (ioctl) {
1887 case KVM_CREATE_VCPU:
1888 r = kvm_vm_ioctl_create_vcpu(kvm, arg);
1889 if (r < 0)
1890 goto out;
1891 break;
1892 case KVM_SET_USER_MEMORY_REGION: {
1893 struct kvm_userspace_memory_region kvm_userspace_mem;
1894
1895 r = -EFAULT;
1896 if (copy_from_user(&kvm_userspace_mem, argp,
1897 sizeof kvm_userspace_mem))
1898 goto out;
1899
1900 r = kvm_vm_ioctl_set_memory_region(kvm, &kvm_userspace_mem, 1);
1901 if (r)
1902 goto out;
1903 break;
1904 }
1905 case KVM_GET_DIRTY_LOG: {
1906 struct kvm_dirty_log log;
1907
1908 r = -EFAULT;
1909 if (copy_from_user(&log, argp, sizeof log))
1910 goto out;
1911 r = kvm_vm_ioctl_get_dirty_log(kvm, &log);
1912 if (r)
1913 goto out;
1914 break;
1915 }
1916 #ifdef KVM_COALESCED_MMIO_PAGE_OFFSET
1917 case KVM_REGISTER_COALESCED_MMIO: {
1918 struct kvm_coalesced_mmio_zone zone;
1919 r = -EFAULT;
1920 if (copy_from_user(&zone, argp, sizeof zone))
1921 goto out;
1922 r = kvm_vm_ioctl_register_coalesced_mmio(kvm, &zone);
1923 if (r)
1924 goto out;
1925 r = 0;
1926 break;
1927 }
1928 case KVM_UNREGISTER_COALESCED_MMIO: {
1929 struct kvm_coalesced_mmio_zone zone;
1930 r = -EFAULT;
1931 if (copy_from_user(&zone, argp, sizeof zone))
1932 goto out;
1933 r = kvm_vm_ioctl_unregister_coalesced_mmio(kvm, &zone);
1934 if (r)
1935 goto out;
1936 r = 0;
1937 break;
1938 }
1939 #endif
1940 case KVM_IRQFD: {
1941 struct kvm_irqfd data;
1942
1943 r = -EFAULT;
1944 if (copy_from_user(&data, argp, sizeof data))
1945 goto out;
1946 r = kvm_irqfd(kvm, data.fd, data.gsi, data.flags);
1947 break;
1948 }
1949 case KVM_IOEVENTFD: {
1950 struct kvm_ioeventfd data;
1951
1952 r = -EFAULT;
1953 if (copy_from_user(&data, argp, sizeof data))
1954 goto out;
1955 r = kvm_ioeventfd(kvm, &data);
1956 break;
1957 }
1958 #ifdef CONFIG_KVM_APIC_ARCHITECTURE
1959 case KVM_SET_BOOT_CPU_ID:
1960 r = 0;
1961 mutex_lock(&kvm->lock);
1962 if (atomic_read(&kvm->online_vcpus) != 0)
1963 r = -EBUSY;
1964 else
1965 kvm->bsp_vcpu_id = arg;
1966 mutex_unlock(&kvm->lock);
1967 break;
1968 #endif
1969 default:
1970 r = kvm_arch_vm_ioctl(filp, ioctl, arg);
1971 if (r == -ENOTTY)
1972 r = kvm_vm_ioctl_assigned_device(kvm, ioctl, arg);
1973 }
1974 out:
1975 return r;
1976 }
1977
1978 #ifdef CONFIG_COMPAT
1979 struct compat_kvm_dirty_log {
1980 __u32 slot;
1981 __u32 padding1;
1982 union {
1983 compat_uptr_t dirty_bitmap; /* one bit per page */
1984 __u64 padding2;
1985 };
1986 };
1987
1988 static long kvm_vm_compat_ioctl(struct file *filp,
1989 unsigned int ioctl, unsigned long arg)
1990 {
1991 struct kvm *kvm = filp->private_data;
1992 int r;
1993
1994 if (kvm->mm != current->mm)
1995 return -EIO;
1996 switch (ioctl) {
1997 case KVM_GET_DIRTY_LOG: {
1998 struct compat_kvm_dirty_log compat_log;
1999 struct kvm_dirty_log log;
2000
2001 r = -EFAULT;
2002 if (copy_from_user(&compat_log, (void __user *)arg,
2003 sizeof(compat_log)))
2004 goto out;
2005 log.slot = compat_log.slot;
2006 log.padding1 = compat_log.padding1;
2007 log.padding2 = compat_log.padding2;
2008 log.dirty_bitmap = compat_ptr(compat_log.dirty_bitmap);
2009
2010 r = kvm_vm_ioctl_get_dirty_log(kvm, &log);
2011 if (r)
2012 goto out;
2013 break;
2014 }
2015 default:
2016 r = kvm_vm_ioctl(filp, ioctl, arg);
2017 }
2018
2019 out:
2020 return r;
2021 }
2022 #endif
2023
2024 static int kvm_vm_fault(struct vm_area_struct *vma, struct vm_fault *vmf)
2025 {
2026 struct page *page[1];
2027 unsigned long addr;
2028 int npages;
2029 gfn_t gfn = vmf->pgoff;
2030 struct kvm *kvm = vma->vm_file->private_data;
2031
2032 addr = gfn_to_hva(kvm, gfn);
2033 if (kvm_is_error_hva(addr))
2034 return VM_FAULT_SIGBUS;
2035
2036 npages = get_user_pages(current, current->mm, addr, 1, 1, 0, page,
2037 NULL);
2038 if (unlikely(npages != 1))
2039 return VM_FAULT_SIGBUS;
2040
2041 vmf->page = page[0];
2042 return 0;
2043 }
2044
2045 static const struct vm_operations_struct kvm_vm_vm_ops = {
2046 .fault = kvm_vm_fault,
2047 };
2048
2049 static int kvm_vm_mmap(struct file *file, struct vm_area_struct *vma)
2050 {
2051 vma->vm_ops = &kvm_vm_vm_ops;
2052 return 0;
2053 }
2054
2055 static struct file_operations kvm_vm_fops = {
2056 .release = kvm_vm_release,
2057 .unlocked_ioctl = kvm_vm_ioctl,
2058 #ifdef CONFIG_COMPAT
2059 .compat_ioctl = kvm_vm_compat_ioctl,
2060 #endif
2061 .mmap = kvm_vm_mmap,
2062 .llseek = noop_llseek,
2063 };
2064
2065 static int kvm_dev_ioctl_create_vm(void)
2066 {
2067 int r;
2068 struct kvm *kvm;
2069
2070 kvm = kvm_create_vm();
2071 if (IS_ERR(kvm))
2072 return PTR_ERR(kvm);
2073 #ifdef KVM_COALESCED_MMIO_PAGE_OFFSET
2074 r = kvm_coalesced_mmio_init(kvm);
2075 if (r < 0) {
2076 kvm_put_kvm(kvm);
2077 return r;
2078 }
2079 #endif
2080 r = anon_inode_getfd("kvm-vm", &kvm_vm_fops, kvm, O_RDWR);
2081 if (r < 0)
2082 kvm_put_kvm(kvm);
2083
2084 return r;
2085 }
2086
2087 static long kvm_dev_ioctl_check_extension_generic(long arg)
2088 {
2089 switch (arg) {
2090 case KVM_CAP_USER_MEMORY:
2091 case KVM_CAP_DESTROY_MEMORY_REGION_WORKS:
2092 case KVM_CAP_JOIN_MEMORY_REGIONS_WORKS:
2093 #ifdef CONFIG_KVM_APIC_ARCHITECTURE
2094 case KVM_CAP_SET_BOOT_CPU_ID:
2095 #endif
2096 case KVM_CAP_INTERNAL_ERROR_DATA:
2097 return 1;
2098 #ifdef CONFIG_HAVE_KVM_IRQCHIP
2099 case KVM_CAP_IRQ_ROUTING:
2100 return KVM_MAX_IRQ_ROUTES;
2101 #endif
2102 default:
2103 break;
2104 }
2105 return kvm_dev_ioctl_check_extension(arg);
2106 }
2107
2108 static long kvm_dev_ioctl(struct file *filp,
2109 unsigned int ioctl, unsigned long arg)
2110 {
2111 long r = -EINVAL;
2112
2113 switch (ioctl) {
2114 case KVM_GET_API_VERSION:
2115 r = -EINVAL;
2116 if (arg)
2117 goto out;
2118 r = KVM_API_VERSION;
2119 break;
2120 case KVM_CREATE_VM:
2121 r = -EINVAL;
2122 if (arg)
2123 goto out;
2124 r = kvm_dev_ioctl_create_vm();
2125 break;
2126 case KVM_CHECK_EXTENSION:
2127 r = kvm_dev_ioctl_check_extension_generic(arg);
2128 break;
2129 case KVM_GET_VCPU_MMAP_SIZE:
2130 r = -EINVAL;
2131 if (arg)
2132 goto out;
2133 r = PAGE_SIZE; /* struct kvm_run */
2134 #ifdef CONFIG_X86
2135 r += PAGE_SIZE; /* pio data page */
2136 #endif
2137 #ifdef KVM_COALESCED_MMIO_PAGE_OFFSET
2138 r += PAGE_SIZE; /* coalesced mmio ring page */
2139 #endif
2140 break;
2141 case KVM_TRACE_ENABLE:
2142 case KVM_TRACE_PAUSE:
2143 case KVM_TRACE_DISABLE:
2144 r = -EOPNOTSUPP;
2145 break;
2146 default:
2147 return kvm_arch_dev_ioctl(filp, ioctl, arg);
2148 }
2149 out:
2150 return r;
2151 }
2152
2153 static struct file_operations kvm_chardev_ops = {
2154 .unlocked_ioctl = kvm_dev_ioctl,
2155 .compat_ioctl = kvm_dev_ioctl,
2156 .llseek = noop_llseek,
2157 };
2158
2159 static struct miscdevice kvm_dev = {
2160 KVM_MINOR,
2161 "kvm",
2162 &kvm_chardev_ops,
2163 };
2164
2165 static void hardware_enable_nolock(void *junk)
2166 {
2167 int cpu = raw_smp_processor_id();
2168 int r;
2169
2170 if (cpumask_test_cpu(cpu, cpus_hardware_enabled))
2171 return;
2172
2173 cpumask_set_cpu(cpu, cpus_hardware_enabled);
2174
2175 r = kvm_arch_hardware_enable(NULL);
2176
2177 if (r) {
2178 cpumask_clear_cpu(cpu, cpus_hardware_enabled);
2179 atomic_inc(&hardware_enable_failed);
2180 printk(KERN_INFO "kvm: enabling virtualization on "
2181 "CPU%d failed\n", cpu);
2182 }
2183 }
2184
2185 static void hardware_enable(void *junk)
2186 {
2187 raw_spin_lock(&kvm_lock);
2188 hardware_enable_nolock(junk);
2189 raw_spin_unlock(&kvm_lock);
2190 }
2191
2192 static void hardware_disable_nolock(void *junk)
2193 {
2194 int cpu = raw_smp_processor_id();
2195
2196 if (!cpumask_test_cpu(cpu, cpus_hardware_enabled))
2197 return;
2198 cpumask_clear_cpu(cpu, cpus_hardware_enabled);
2199 kvm_arch_hardware_disable(NULL);
2200 }
2201
2202 static void hardware_disable(void *junk)
2203 {
2204 raw_spin_lock(&kvm_lock);
2205 hardware_disable_nolock(junk);
2206 raw_spin_unlock(&kvm_lock);
2207 }
2208
2209 static void hardware_disable_all_nolock(void)
2210 {
2211 BUG_ON(!kvm_usage_count);
2212
2213 kvm_usage_count--;
2214 if (!kvm_usage_count)
2215 on_each_cpu(hardware_disable_nolock, NULL, 1);
2216 }
2217
2218 static void hardware_disable_all(void)
2219 {
2220 raw_spin_lock(&kvm_lock);
2221 hardware_disable_all_nolock();
2222 raw_spin_unlock(&kvm_lock);
2223 }
2224
2225 static int hardware_enable_all(void)
2226 {
2227 int r = 0;
2228
2229 raw_spin_lock(&kvm_lock);
2230
2231 kvm_usage_count++;
2232 if (kvm_usage_count == 1) {
2233 atomic_set(&hardware_enable_failed, 0);
2234 on_each_cpu(hardware_enable_nolock, NULL, 1);
2235
2236 if (atomic_read(&hardware_enable_failed)) {
2237 hardware_disable_all_nolock();
2238 r = -EBUSY;
2239 }
2240 }
2241
2242 raw_spin_unlock(&kvm_lock);
2243
2244 return r;
2245 }
2246
2247 static int kvm_cpu_hotplug(struct notifier_block *notifier, unsigned long val,
2248 void *v)
2249 {
2250 int cpu = (long)v;
2251
2252 if (!kvm_usage_count)
2253 return NOTIFY_OK;
2254
2255 val &= ~CPU_TASKS_FROZEN;
2256 switch (val) {
2257 case CPU_DYING:
2258 printk(KERN_INFO "kvm: disabling virtualization on CPU%d\n",
2259 cpu);
2260 hardware_disable(NULL);
2261 break;
2262 case CPU_STARTING:
2263 printk(KERN_INFO "kvm: enabling virtualization on CPU%d\n",
2264 cpu);
2265 hardware_enable(NULL);
2266 break;
2267 }
2268 return NOTIFY_OK;
2269 }
2270
2271
2272 asmlinkage void kvm_spurious_fault(void)
2273 {
2274 /* Fault while not rebooting. We want the trace. */
2275 BUG();
2276 }
2277 EXPORT_SYMBOL_GPL(kvm_spurious_fault);
2278
2279 static int kvm_reboot(struct notifier_block *notifier, unsigned long val,
2280 void *v)
2281 {
2282 /*
2283 * Some (well, at least mine) BIOSes hang on reboot if
2284 * in vmx root mode.
2285 *
2286 * And Intel TXT required VMX off for all cpu when system shutdown.
2287 */
2288 printk(KERN_INFO "kvm: exiting hardware virtualization\n");
2289 kvm_rebooting = true;
2290 on_each_cpu(hardware_disable_nolock, NULL, 1);
2291 return NOTIFY_OK;
2292 }
2293
2294 static struct notifier_block kvm_reboot_notifier = {
2295 .notifier_call = kvm_reboot,
2296 .priority = 0,
2297 };
2298
2299 static void kvm_io_bus_destroy(struct kvm_io_bus *bus)
2300 {
2301 int i;
2302
2303 for (i = 0; i < bus->dev_count; i++) {
2304 struct kvm_io_device *pos = bus->devs[i];
2305
2306 kvm_iodevice_destructor(pos);
2307 }
2308 kfree(bus);
2309 }
2310
2311 /* kvm_io_bus_write - called under kvm->slots_lock */
2312 int kvm_io_bus_write(struct kvm *kvm, enum kvm_bus bus_idx, gpa_t addr,
2313 int len, const void *val)
2314 {
2315 int i;
2316 struct kvm_io_bus *bus;
2317
2318 bus = srcu_dereference(kvm->buses[bus_idx], &kvm->srcu);
2319 for (i = 0; i < bus->dev_count; i++)
2320 if (!kvm_iodevice_write(bus->devs[i], addr, len, val))
2321 return 0;
2322 return -EOPNOTSUPP;
2323 }
2324
2325 /* kvm_io_bus_read - called under kvm->slots_lock */
2326 int kvm_io_bus_read(struct kvm *kvm, enum kvm_bus bus_idx, gpa_t addr,
2327 int len, void *val)
2328 {
2329 int i;
2330 struct kvm_io_bus *bus;
2331
2332 bus = srcu_dereference(kvm->buses[bus_idx], &kvm->srcu);
2333 for (i = 0; i < bus->dev_count; i++)
2334 if (!kvm_iodevice_read(bus->devs[i], addr, len, val))
2335 return 0;
2336 return -EOPNOTSUPP;
2337 }
2338
2339 /* Caller must hold slots_lock. */
2340 int kvm_io_bus_register_dev(struct kvm *kvm, enum kvm_bus bus_idx,
2341 struct kvm_io_device *dev)
2342 {
2343 struct kvm_io_bus *new_bus, *bus;
2344
2345 bus = kvm->buses[bus_idx];
2346 if (bus->dev_count > NR_IOBUS_DEVS-1)
2347 return -ENOSPC;
2348
2349 new_bus = kzalloc(sizeof(struct kvm_io_bus), GFP_KERNEL);
2350 if (!new_bus)
2351 return -ENOMEM;
2352 memcpy(new_bus, bus, sizeof(struct kvm_io_bus));
2353 new_bus->devs[new_bus->dev_count++] = dev;
2354 rcu_assign_pointer(kvm->buses[bus_idx], new_bus);
2355 synchronize_srcu_expedited(&kvm->srcu);
2356 kfree(bus);
2357
2358 return 0;
2359 }
2360
2361 /* Caller must hold slots_lock. */
2362 int kvm_io_bus_unregister_dev(struct kvm *kvm, enum kvm_bus bus_idx,
2363 struct kvm_io_device *dev)
2364 {
2365 int i, r;
2366 struct kvm_io_bus *new_bus, *bus;
2367
2368 new_bus = kzalloc(sizeof(struct kvm_io_bus), GFP_KERNEL);
2369 if (!new_bus)
2370 return -ENOMEM;
2371
2372 bus = kvm->buses[bus_idx];
2373 memcpy(new_bus, bus, sizeof(struct kvm_io_bus));
2374
2375 r = -ENOENT;
2376 for (i = 0; i < new_bus->dev_count; i++)
2377 if (new_bus->devs[i] == dev) {
2378 r = 0;
2379 new_bus->devs[i] = new_bus->devs[--new_bus->dev_count];
2380 break;
2381 }
2382
2383 if (r) {
2384 kfree(new_bus);
2385 return r;
2386 }
2387
2388 rcu_assign_pointer(kvm->buses[bus_idx], new_bus);
2389 synchronize_srcu_expedited(&kvm->srcu);
2390 kfree(bus);
2391 return r;
2392 }
2393
2394 static struct notifier_block kvm_cpu_notifier = {
2395 .notifier_call = kvm_cpu_hotplug,
2396 };
2397
2398 static int vm_stat_get(void *_offset, u64 *val)
2399 {
2400 unsigned offset = (long)_offset;
2401 struct kvm *kvm;
2402
2403 *val = 0;
2404 raw_spin_lock(&kvm_lock);
2405 list_for_each_entry(kvm, &vm_list, vm_list)
2406 *val += *(u32 *)((void *)kvm + offset);
2407 raw_spin_unlock(&kvm_lock);
2408 return 0;
2409 }
2410
2411 DEFINE_SIMPLE_ATTRIBUTE(vm_stat_fops, vm_stat_get, NULL, "%llu\n");
2412
2413 static int vcpu_stat_get(void *_offset, u64 *val)
2414 {
2415 unsigned offset = (long)_offset;
2416 struct kvm *kvm;
2417 struct kvm_vcpu *vcpu;
2418 int i;
2419
2420 *val = 0;
2421 raw_spin_lock(&kvm_lock);
2422 list_for_each_entry(kvm, &vm_list, vm_list)
2423 kvm_for_each_vcpu(i, vcpu, kvm)
2424 *val += *(u32 *)((void *)vcpu + offset);
2425
2426 raw_spin_unlock(&kvm_lock);
2427 return 0;
2428 }
2429
2430 DEFINE_SIMPLE_ATTRIBUTE(vcpu_stat_fops, vcpu_stat_get, NULL, "%llu\n");
2431
2432 static const struct file_operations *stat_fops[] = {
2433 [KVM_STAT_VCPU] = &vcpu_stat_fops,
2434 [KVM_STAT_VM] = &vm_stat_fops,
2435 };
2436
2437 static void kvm_init_debug(void)
2438 {
2439 struct kvm_stats_debugfs_item *p;
2440
2441 kvm_debugfs_dir = debugfs_create_dir("kvm", NULL);
2442 for (p = debugfs_entries; p->name; ++p)
2443 p->dentry = debugfs_create_file(p->name, 0444, kvm_debugfs_dir,
2444 (void *)(long)p->offset,
2445 stat_fops[p->kind]);
2446 }
2447
2448 static void kvm_exit_debug(void)
2449 {
2450 struct kvm_stats_debugfs_item *p;
2451
2452 for (p = debugfs_entries; p->name; ++p)
2453 debugfs_remove(p->dentry);
2454 debugfs_remove(kvm_debugfs_dir);
2455 }
2456
2457 static int kvm_suspend(void)
2458 {
2459 if (kvm_usage_count)
2460 hardware_disable_nolock(NULL);
2461 return 0;
2462 }
2463
2464 static void kvm_resume(void)
2465 {
2466 if (kvm_usage_count) {
2467 WARN_ON(raw_spin_is_locked(&kvm_lock));
2468 hardware_enable_nolock(NULL);
2469 }
2470 }
2471
2472 static struct syscore_ops kvm_syscore_ops = {
2473 .suspend = kvm_suspend,
2474 .resume = kvm_resume,
2475 };
2476
2477 struct page *bad_page;
2478 pfn_t bad_pfn;
2479
2480 static inline
2481 struct kvm_vcpu *preempt_notifier_to_vcpu(struct preempt_notifier *pn)
2482 {
2483 return container_of(pn, struct kvm_vcpu, preempt_notifier);
2484 }
2485
2486 static void kvm_sched_in(struct preempt_notifier *pn, int cpu)
2487 {
2488 struct kvm_vcpu *vcpu = preempt_notifier_to_vcpu(pn);
2489
2490 kvm_arch_vcpu_load(vcpu, cpu);
2491 }
2492
2493 static void kvm_sched_out(struct preempt_notifier *pn,
2494 struct task_struct *next)
2495 {
2496 struct kvm_vcpu *vcpu = preempt_notifier_to_vcpu(pn);
2497
2498 kvm_arch_vcpu_put(vcpu);
2499 }
2500
2501 int kvm_init(void *opaque, unsigned vcpu_size, unsigned vcpu_align,
2502 struct module *module)
2503 {
2504 int r;
2505 int cpu;
2506
2507 r = kvm_arch_init(opaque);
2508 if (r)
2509 goto out_fail;
2510
2511 bad_page = alloc_page(GFP_KERNEL | __GFP_ZERO);
2512
2513 if (bad_page == NULL) {
2514 r = -ENOMEM;
2515 goto out;
2516 }
2517
2518 bad_pfn = page_to_pfn(bad_page);
2519
2520 hwpoison_page = alloc_page(GFP_KERNEL | __GFP_ZERO);
2521
2522 if (hwpoison_page == NULL) {
2523 r = -ENOMEM;
2524 goto out_free_0;
2525 }
2526
2527 hwpoison_pfn = page_to_pfn(hwpoison_page);
2528
2529 fault_page = alloc_page(GFP_KERNEL | __GFP_ZERO);
2530
2531 if (fault_page == NULL) {
2532 r = -ENOMEM;
2533 goto out_free_0;
2534 }
2535
2536 fault_pfn = page_to_pfn(fault_page);
2537
2538 if (!zalloc_cpumask_var(&cpus_hardware_enabled, GFP_KERNEL)) {
2539 r = -ENOMEM;
2540 goto out_free_0;
2541 }
2542
2543 r = kvm_arch_hardware_setup();
2544 if (r < 0)
2545 goto out_free_0a;
2546
2547 for_each_online_cpu(cpu) {
2548 smp_call_function_single(cpu,
2549 kvm_arch_check_processor_compat,
2550 &r, 1);
2551 if (r < 0)
2552 goto out_free_1;
2553 }
2554
2555 r = register_cpu_notifier(&kvm_cpu_notifier);
2556 if (r)
2557 goto out_free_2;
2558 register_reboot_notifier(&kvm_reboot_notifier);
2559
2560 /* A kmem cache lets us meet the alignment requirements of fx_save. */
2561 if (!vcpu_align)
2562 vcpu_align = __alignof__(struct kvm_vcpu);
2563 kvm_vcpu_cache = kmem_cache_create("kvm_vcpu", vcpu_size, vcpu_align,
2564 0, NULL);
2565 if (!kvm_vcpu_cache) {
2566 r = -ENOMEM;
2567 goto out_free_3;
2568 }
2569
2570 r = kvm_async_pf_init();
2571 if (r)
2572 goto out_free;
2573
2574 kvm_chardev_ops.owner = module;
2575 kvm_vm_fops.owner = module;
2576 kvm_vcpu_fops.owner = module;
2577
2578 r = misc_register(&kvm_dev);
2579 if (r) {
2580 printk(KERN_ERR "kvm: misc device register failed\n");
2581 goto out_unreg;
2582 }
2583
2584 register_syscore_ops(&kvm_syscore_ops);
2585
2586 kvm_preempt_ops.sched_in = kvm_sched_in;
2587 kvm_preempt_ops.sched_out = kvm_sched_out;
2588
2589 kvm_init_debug();
2590
2591 return 0;
2592
2593 out_unreg:
2594 kvm_async_pf_deinit();
2595 out_free:
2596 kmem_cache_destroy(kvm_vcpu_cache);
2597 out_free_3:
2598 unregister_reboot_notifier(&kvm_reboot_notifier);
2599 unregister_cpu_notifier(&kvm_cpu_notifier);
2600 out_free_2:
2601 out_free_1:
2602 kvm_arch_hardware_unsetup();
2603 out_free_0a:
2604 free_cpumask_var(cpus_hardware_enabled);
2605 out_free_0:
2606 if (fault_page)
2607 __free_page(fault_page);
2608 if (hwpoison_page)
2609 __free_page(hwpoison_page);
2610 __free_page(bad_page);
2611 out:
2612 kvm_arch_exit();
2613 out_fail:
2614 return r;
2615 }
2616 EXPORT_SYMBOL_GPL(kvm_init);
2617
2618 void kvm_exit(void)
2619 {
2620 kvm_exit_debug();
2621 misc_deregister(&kvm_dev);
2622 kmem_cache_destroy(kvm_vcpu_cache);
2623 kvm_async_pf_deinit();
2624 unregister_syscore_ops(&kvm_syscore_ops);
2625 unregister_reboot_notifier(&kvm_reboot_notifier);
2626 unregister_cpu_notifier(&kvm_cpu_notifier);
2627 on_each_cpu(hardware_disable_nolock, NULL, 1);
2628 kvm_arch_hardware_unsetup();
2629 kvm_arch_exit();
2630 free_cpumask_var(cpus_hardware_enabled);
2631 __free_page(hwpoison_page);
2632 __free_page(bad_page);
2633 }
2634 EXPORT_SYMBOL_GPL(kvm_exit);
linux-next