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sched: Fix signedness bug in yield_to()
[mirror_ubuntu-zesty-kernel.git] / virt / kvm / kvm_main.c
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 #include <linux/sort.h>
51 #include <linux/bsearch.h>
52
53 #include <asm/processor.h>
54 #include <asm/io.h>
55 #include <asm/uaccess.h>
56 #include <asm/pgtable.h>
57
58 #include "coalesced_mmio.h"
59 #include "async_pf.h"
60
61 #define CREATE_TRACE_POINTS
62 #include <trace/events/kvm.h>
63
64 MODULE_AUTHOR("Qumranet");
65 MODULE_LICENSE("GPL");
66
67 /*
68 * Ordering of locks:
69 *
70 * kvm->lock --> kvm->slots_lock --> kvm->irq_lock
71 */
72
73 DEFINE_SPINLOCK(kvm_lock);
74 static DEFINE_RAW_SPINLOCK(kvm_count_lock);
75 LIST_HEAD(vm_list);
76
77 static cpumask_var_t cpus_hardware_enabled;
78 static int kvm_usage_count = 0;
79 static atomic_t hardware_enable_failed;
80
81 struct kmem_cache *kvm_vcpu_cache;
82 EXPORT_SYMBOL_GPL(kvm_vcpu_cache);
83
84 static __read_mostly struct preempt_ops kvm_preempt_ops;
85
86 struct dentry *kvm_debugfs_dir;
87
88 static long kvm_vcpu_ioctl(struct file *file, unsigned int ioctl,
89 unsigned long arg);
90 #ifdef CONFIG_COMPAT
91 static long kvm_vcpu_compat_ioctl(struct file *file, unsigned int ioctl,
92 unsigned long arg);
93 #endif
94 static int hardware_enable_all(void);
95 static void hardware_disable_all(void);
96
97 static void kvm_io_bus_destroy(struct kvm_io_bus *bus);
98 static void update_memslots(struct kvm_memslots *slots,
99 struct kvm_memory_slot *new, u64 last_generation);
100
101 static void kvm_release_pfn_dirty(pfn_t pfn);
102 static void mark_page_dirty_in_slot(struct kvm *kvm,
103 struct kvm_memory_slot *memslot, gfn_t gfn);
104
105 __visible bool kvm_rebooting;
106 EXPORT_SYMBOL_GPL(kvm_rebooting);
107
108 static bool largepages_enabled = true;
109
110 bool kvm_is_mmio_pfn(pfn_t pfn)
111 {
112 if (pfn_valid(pfn))
113 return PageReserved(pfn_to_page(pfn));
114
115 return true;
116 }
117
118 /*
119 * Switches to specified vcpu, until a matching vcpu_put()
120 */
121 int vcpu_load(struct kvm_vcpu *vcpu)
122 {
123 int cpu;
124
125 if (mutex_lock_killable(&vcpu->mutex))
126 return -EINTR;
127 if (unlikely(vcpu->pid != current->pids[PIDTYPE_PID].pid)) {
128 /* The thread running this VCPU changed. */
129 struct pid *oldpid = vcpu->pid;
130 struct pid *newpid = get_task_pid(current, PIDTYPE_PID);
131 rcu_assign_pointer(vcpu->pid, newpid);
132 synchronize_rcu();
133 put_pid(oldpid);
134 }
135 cpu = get_cpu();
136 preempt_notifier_register(&vcpu->preempt_notifier);
137 kvm_arch_vcpu_load(vcpu, cpu);
138 put_cpu();
139 return 0;
140 }
141
142 void vcpu_put(struct kvm_vcpu *vcpu)
143 {
144 preempt_disable();
145 kvm_arch_vcpu_put(vcpu);
146 preempt_notifier_unregister(&vcpu->preempt_notifier);
147 preempt_enable();
148 mutex_unlock(&vcpu->mutex);
149 }
150
151 static void ack_flush(void *_completed)
152 {
153 }
154
155 static bool make_all_cpus_request(struct kvm *kvm, unsigned int req)
156 {
157 int i, cpu, me;
158 cpumask_var_t cpus;
159 bool called = true;
160 struct kvm_vcpu *vcpu;
161
162 zalloc_cpumask_var(&cpus, GFP_ATOMIC);
163
164 me = get_cpu();
165 kvm_for_each_vcpu(i, vcpu, kvm) {
166 kvm_make_request(req, vcpu);
167 cpu = vcpu->cpu;
168
169 /* Set ->requests bit before we read ->mode */
170 smp_mb();
171
172 if (cpus != NULL && cpu != -1 && cpu != me &&
173 kvm_vcpu_exiting_guest_mode(vcpu) != OUTSIDE_GUEST_MODE)
174 cpumask_set_cpu(cpu, cpus);
175 }
176 if (unlikely(cpus == NULL))
177 smp_call_function_many(cpu_online_mask, ack_flush, NULL, 1);
178 else if (!cpumask_empty(cpus))
179 smp_call_function_many(cpus, ack_flush, NULL, 1);
180 else
181 called = false;
182 put_cpu();
183 free_cpumask_var(cpus);
184 return called;
185 }
186
187 void kvm_flush_remote_tlbs(struct kvm *kvm)
188 {
189 if (make_all_cpus_request(kvm, KVM_REQ_TLB_FLUSH))
190 ++kvm->stat.remote_tlb_flush;
191 kvm->tlbs_dirty = false;
192 }
193 EXPORT_SYMBOL_GPL(kvm_flush_remote_tlbs);
194
195 void kvm_reload_remote_mmus(struct kvm *kvm)
196 {
197 make_all_cpus_request(kvm, KVM_REQ_MMU_RELOAD);
198 }
199
200 void kvm_make_mclock_inprogress_request(struct kvm *kvm)
201 {
202 make_all_cpus_request(kvm, KVM_REQ_MCLOCK_INPROGRESS);
203 }
204
205 void kvm_make_scan_ioapic_request(struct kvm *kvm)
206 {
207 make_all_cpus_request(kvm, KVM_REQ_SCAN_IOAPIC);
208 }
209
210 int kvm_vcpu_init(struct kvm_vcpu *vcpu, struct kvm *kvm, unsigned id)
211 {
212 struct page *page;
213 int r;
214
215 mutex_init(&vcpu->mutex);
216 vcpu->cpu = -1;
217 vcpu->kvm = kvm;
218 vcpu->vcpu_id = id;
219 vcpu->pid = NULL;
220 init_waitqueue_head(&vcpu->wq);
221 kvm_async_pf_vcpu_init(vcpu);
222
223 page = alloc_page(GFP_KERNEL | __GFP_ZERO);
224 if (!page) {
225 r = -ENOMEM;
226 goto fail;
227 }
228 vcpu->run = page_address(page);
229
230 kvm_vcpu_set_in_spin_loop(vcpu, false);
231 kvm_vcpu_set_dy_eligible(vcpu, false);
232 vcpu->preempted = false;
233
234 r = kvm_arch_vcpu_init(vcpu);
235 if (r < 0)
236 goto fail_free_run;
237 return 0;
238
239 fail_free_run:
240 free_page((unsigned long)vcpu->run);
241 fail:
242 return r;
243 }
244 EXPORT_SYMBOL_GPL(kvm_vcpu_init);
245
246 void kvm_vcpu_uninit(struct kvm_vcpu *vcpu)
247 {
248 put_pid(vcpu->pid);
249 kvm_arch_vcpu_uninit(vcpu);
250 free_page((unsigned long)vcpu->run);
251 }
252 EXPORT_SYMBOL_GPL(kvm_vcpu_uninit);
253
254 #if defined(CONFIG_MMU_NOTIFIER) && defined(KVM_ARCH_WANT_MMU_NOTIFIER)
255 static inline struct kvm *mmu_notifier_to_kvm(struct mmu_notifier *mn)
256 {
257 return container_of(mn, struct kvm, mmu_notifier);
258 }
259
260 static void kvm_mmu_notifier_invalidate_page(struct mmu_notifier *mn,
261 struct mm_struct *mm,
262 unsigned long address)
263 {
264 struct kvm *kvm = mmu_notifier_to_kvm(mn);
265 int need_tlb_flush, idx;
266
267 /*
268 * When ->invalidate_page runs, the linux pte has been zapped
269 * already but the page is still allocated until
270 * ->invalidate_page returns. So if we increase the sequence
271 * here the kvm page fault will notice if the spte can't be
272 * established because the page is going to be freed. If
273 * instead the kvm page fault establishes the spte before
274 * ->invalidate_page runs, kvm_unmap_hva will release it
275 * before returning.
276 *
277 * The sequence increase only need to be seen at spin_unlock
278 * time, and not at spin_lock time.
279 *
280 * Increasing the sequence after the spin_unlock would be
281 * unsafe because the kvm page fault could then establish the
282 * pte after kvm_unmap_hva returned, without noticing the page
283 * is going to be freed.
284 */
285 idx = srcu_read_lock(&kvm->srcu);
286 spin_lock(&kvm->mmu_lock);
287
288 kvm->mmu_notifier_seq++;
289 need_tlb_flush = kvm_unmap_hva(kvm, address) | kvm->tlbs_dirty;
290 /* we've to flush the tlb before the pages can be freed */
291 if (need_tlb_flush)
292 kvm_flush_remote_tlbs(kvm);
293
294 spin_unlock(&kvm->mmu_lock);
295 srcu_read_unlock(&kvm->srcu, idx);
296 }
297
298 static void kvm_mmu_notifier_change_pte(struct mmu_notifier *mn,
299 struct mm_struct *mm,
300 unsigned long address,
301 pte_t pte)
302 {
303 struct kvm *kvm = mmu_notifier_to_kvm(mn);
304 int idx;
305
306 idx = srcu_read_lock(&kvm->srcu);
307 spin_lock(&kvm->mmu_lock);
308 kvm->mmu_notifier_seq++;
309 kvm_set_spte_hva(kvm, address, pte);
310 spin_unlock(&kvm->mmu_lock);
311 srcu_read_unlock(&kvm->srcu, idx);
312 }
313
314 static void kvm_mmu_notifier_invalidate_range_start(struct mmu_notifier *mn,
315 struct mm_struct *mm,
316 unsigned long start,
317 unsigned long end)
318 {
319 struct kvm *kvm = mmu_notifier_to_kvm(mn);
320 int need_tlb_flush = 0, idx;
321
322 idx = srcu_read_lock(&kvm->srcu);
323 spin_lock(&kvm->mmu_lock);
324 /*
325 * The count increase must become visible at unlock time as no
326 * spte can be established without taking the mmu_lock and
327 * count is also read inside the mmu_lock critical section.
328 */
329 kvm->mmu_notifier_count++;
330 need_tlb_flush = kvm_unmap_hva_range(kvm, start, end);
331 need_tlb_flush |= kvm->tlbs_dirty;
332 /* we've to flush the tlb before the pages can be freed */
333 if (need_tlb_flush)
334 kvm_flush_remote_tlbs(kvm);
335
336 spin_unlock(&kvm->mmu_lock);
337 srcu_read_unlock(&kvm->srcu, idx);
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 smp_wmb();
355 /*
356 * The above sequence increase must be visible before the
357 * below count decrease, which is ensured by the smp_wmb above
358 * in conjunction with the smp_rmb in mmu_notifier_retry().
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
376 young = kvm_age_hva(kvm, address);
377 if (young)
378 kvm_flush_remote_tlbs(kvm);
379
380 spin_unlock(&kvm->mmu_lock);
381 srcu_read_unlock(&kvm->srcu, idx);
382
383 return young;
384 }
385
386 static int kvm_mmu_notifier_test_young(struct mmu_notifier *mn,
387 struct mm_struct *mm,
388 unsigned long address)
389 {
390 struct kvm *kvm = mmu_notifier_to_kvm(mn);
391 int young, idx;
392
393 idx = srcu_read_lock(&kvm->srcu);
394 spin_lock(&kvm->mmu_lock);
395 young = kvm_test_age_hva(kvm, address);
396 spin_unlock(&kvm->mmu_lock);
397 srcu_read_unlock(&kvm->srcu, idx);
398
399 return young;
400 }
401
402 static void kvm_mmu_notifier_release(struct mmu_notifier *mn,
403 struct mm_struct *mm)
404 {
405 struct kvm *kvm = mmu_notifier_to_kvm(mn);
406 int idx;
407
408 idx = srcu_read_lock(&kvm->srcu);
409 kvm_arch_flush_shadow_all(kvm);
410 srcu_read_unlock(&kvm->srcu, idx);
411 }
412
413 static const struct mmu_notifier_ops kvm_mmu_notifier_ops = {
414 .invalidate_page = kvm_mmu_notifier_invalidate_page,
415 .invalidate_range_start = kvm_mmu_notifier_invalidate_range_start,
416 .invalidate_range_end = kvm_mmu_notifier_invalidate_range_end,
417 .clear_flush_young = kvm_mmu_notifier_clear_flush_young,
418 .test_young = kvm_mmu_notifier_test_young,
419 .change_pte = kvm_mmu_notifier_change_pte,
420 .release = kvm_mmu_notifier_release,
421 };
422
423 static int kvm_init_mmu_notifier(struct kvm *kvm)
424 {
425 kvm->mmu_notifier.ops = &kvm_mmu_notifier_ops;
426 return mmu_notifier_register(&kvm->mmu_notifier, current->mm);
427 }
428
429 #else /* !(CONFIG_MMU_NOTIFIER && KVM_ARCH_WANT_MMU_NOTIFIER) */
430
431 static int kvm_init_mmu_notifier(struct kvm *kvm)
432 {
433 return 0;
434 }
435
436 #endif /* CONFIG_MMU_NOTIFIER && KVM_ARCH_WANT_MMU_NOTIFIER */
437
438 static void kvm_init_memslots_id(struct kvm *kvm)
439 {
440 int i;
441 struct kvm_memslots *slots = kvm->memslots;
442
443 for (i = 0; i < KVM_MEM_SLOTS_NUM; i++)
444 slots->id_to_index[i] = slots->memslots[i].id = i;
445 }
446
447 static struct kvm *kvm_create_vm(unsigned long type)
448 {
449 int r, i;
450 struct kvm *kvm = kvm_arch_alloc_vm();
451
452 if (!kvm)
453 return ERR_PTR(-ENOMEM);
454
455 r = kvm_arch_init_vm(kvm, type);
456 if (r)
457 goto out_err_nodisable;
458
459 r = hardware_enable_all();
460 if (r)
461 goto out_err_nodisable;
462
463 #ifdef CONFIG_HAVE_KVM_IRQCHIP
464 INIT_HLIST_HEAD(&kvm->mask_notifier_list);
465 INIT_HLIST_HEAD(&kvm->irq_ack_notifier_list);
466 #endif
467
468 BUILD_BUG_ON(KVM_MEM_SLOTS_NUM > SHRT_MAX);
469
470 r = -ENOMEM;
471 kvm->memslots = kzalloc(sizeof(struct kvm_memslots), GFP_KERNEL);
472 if (!kvm->memslots)
473 goto out_err_nosrcu;
474 kvm_init_memslots_id(kvm);
475 if (init_srcu_struct(&kvm->srcu))
476 goto out_err_nosrcu;
477 for (i = 0; i < KVM_NR_BUSES; i++) {
478 kvm->buses[i] = kzalloc(sizeof(struct kvm_io_bus),
479 GFP_KERNEL);
480 if (!kvm->buses[i])
481 goto out_err;
482 }
483
484 spin_lock_init(&kvm->mmu_lock);
485 kvm->mm = current->mm;
486 atomic_inc(&kvm->mm->mm_count);
487 kvm_eventfd_init(kvm);
488 mutex_init(&kvm->lock);
489 mutex_init(&kvm->irq_lock);
490 mutex_init(&kvm->slots_lock);
491 atomic_set(&kvm->users_count, 1);
492 INIT_LIST_HEAD(&kvm->devices);
493
494 r = kvm_init_mmu_notifier(kvm);
495 if (r)
496 goto out_err;
497
498 spin_lock(&kvm_lock);
499 list_add(&kvm->vm_list, &vm_list);
500 spin_unlock(&kvm_lock);
501
502 return kvm;
503
504 out_err:
505 cleanup_srcu_struct(&kvm->srcu);
506 out_err_nosrcu:
507 hardware_disable_all();
508 out_err_nodisable:
509 for (i = 0; i < KVM_NR_BUSES; i++)
510 kfree(kvm->buses[i]);
511 kfree(kvm->memslots);
512 kvm_arch_free_vm(kvm);
513 return ERR_PTR(r);
514 }
515
516 /*
517 * Avoid using vmalloc for a small buffer.
518 * Should not be used when the size is statically known.
519 */
520 void *kvm_kvzalloc(unsigned long size)
521 {
522 if (size > PAGE_SIZE)
523 return vzalloc(size);
524 else
525 return kzalloc(size, GFP_KERNEL);
526 }
527
528 void kvm_kvfree(const void *addr)
529 {
530 if (is_vmalloc_addr(addr))
531 vfree(addr);
532 else
533 kfree(addr);
534 }
535
536 static void kvm_destroy_dirty_bitmap(struct kvm_memory_slot *memslot)
537 {
538 if (!memslot->dirty_bitmap)
539 return;
540
541 kvm_kvfree(memslot->dirty_bitmap);
542 memslot->dirty_bitmap = NULL;
543 }
544
545 /*
546 * Free any memory in @free but not in @dont.
547 */
548 static void kvm_free_physmem_slot(struct kvm *kvm, struct kvm_memory_slot *free,
549 struct kvm_memory_slot *dont)
550 {
551 if (!dont || free->dirty_bitmap != dont->dirty_bitmap)
552 kvm_destroy_dirty_bitmap(free);
553
554 kvm_arch_free_memslot(kvm, free, dont);
555
556 free->npages = 0;
557 }
558
559 static void kvm_free_physmem(struct kvm *kvm)
560 {
561 struct kvm_memslots *slots = kvm->memslots;
562 struct kvm_memory_slot *memslot;
563
564 kvm_for_each_memslot(memslot, slots)
565 kvm_free_physmem_slot(kvm, memslot, NULL);
566
567 kfree(kvm->memslots);
568 }
569
570 static void kvm_destroy_devices(struct kvm *kvm)
571 {
572 struct list_head *node, *tmp;
573
574 list_for_each_safe(node, tmp, &kvm->devices) {
575 struct kvm_device *dev =
576 list_entry(node, struct kvm_device, vm_node);
577
578 list_del(node);
579 dev->ops->destroy(dev);
580 }
581 }
582
583 static void kvm_destroy_vm(struct kvm *kvm)
584 {
585 int i;
586 struct mm_struct *mm = kvm->mm;
587
588 kvm_arch_sync_events(kvm);
589 spin_lock(&kvm_lock);
590 list_del(&kvm->vm_list);
591 spin_unlock(&kvm_lock);
592 kvm_free_irq_routing(kvm);
593 for (i = 0; i < KVM_NR_BUSES; i++)
594 kvm_io_bus_destroy(kvm->buses[i]);
595 kvm_coalesced_mmio_free(kvm);
596 #if defined(CONFIG_MMU_NOTIFIER) && defined(KVM_ARCH_WANT_MMU_NOTIFIER)
597 mmu_notifier_unregister(&kvm->mmu_notifier, kvm->mm);
598 #else
599 kvm_arch_flush_shadow_all(kvm);
600 #endif
601 kvm_arch_destroy_vm(kvm);
602 kvm_destroy_devices(kvm);
603 kvm_free_physmem(kvm);
604 cleanup_srcu_struct(&kvm->srcu);
605 kvm_arch_free_vm(kvm);
606 hardware_disable_all();
607 mmdrop(mm);
608 }
609
610 void kvm_get_kvm(struct kvm *kvm)
611 {
612 atomic_inc(&kvm->users_count);
613 }
614 EXPORT_SYMBOL_GPL(kvm_get_kvm);
615
616 void kvm_put_kvm(struct kvm *kvm)
617 {
618 if (atomic_dec_and_test(&kvm->users_count))
619 kvm_destroy_vm(kvm);
620 }
621 EXPORT_SYMBOL_GPL(kvm_put_kvm);
622
623
624 static int kvm_vm_release(struct inode *inode, struct file *filp)
625 {
626 struct kvm *kvm = filp->private_data;
627
628 kvm_irqfd_release(kvm);
629
630 kvm_put_kvm(kvm);
631 return 0;
632 }
633
634 /*
635 * Allocation size is twice as large as the actual dirty bitmap size.
636 * See x86's kvm_vm_ioctl_get_dirty_log() why this is needed.
637 */
638 static int kvm_create_dirty_bitmap(struct kvm_memory_slot *memslot)
639 {
640 #ifndef CONFIG_S390
641 unsigned long dirty_bytes = 2 * kvm_dirty_bitmap_bytes(memslot);
642
643 memslot->dirty_bitmap = kvm_kvzalloc(dirty_bytes);
644 if (!memslot->dirty_bitmap)
645 return -ENOMEM;
646
647 #endif /* !CONFIG_S390 */
648 return 0;
649 }
650
651 static int cmp_memslot(const void *slot1, const void *slot2)
652 {
653 struct kvm_memory_slot *s1, *s2;
654
655 s1 = (struct kvm_memory_slot *)slot1;
656 s2 = (struct kvm_memory_slot *)slot2;
657
658 if (s1->npages < s2->npages)
659 return 1;
660 if (s1->npages > s2->npages)
661 return -1;
662
663 return 0;
664 }
665
666 /*
667 * Sort the memslots base on its size, so the larger slots
668 * will get better fit.
669 */
670 static void sort_memslots(struct kvm_memslots *slots)
671 {
672 int i;
673
674 sort(slots->memslots, KVM_MEM_SLOTS_NUM,
675 sizeof(struct kvm_memory_slot), cmp_memslot, NULL);
676
677 for (i = 0; i < KVM_MEM_SLOTS_NUM; i++)
678 slots->id_to_index[slots->memslots[i].id] = i;
679 }
680
681 static void update_memslots(struct kvm_memslots *slots,
682 struct kvm_memory_slot *new,
683 u64 last_generation)
684 {
685 if (new) {
686 int id = new->id;
687 struct kvm_memory_slot *old = id_to_memslot(slots, id);
688 unsigned long npages = old->npages;
689
690 *old = *new;
691 if (new->npages != npages)
692 sort_memslots(slots);
693 }
694
695 slots->generation = last_generation + 1;
696 }
697
698 static int check_memory_region_flags(struct kvm_userspace_memory_region *mem)
699 {
700 u32 valid_flags = KVM_MEM_LOG_DIRTY_PAGES;
701
702 #ifdef KVM_CAP_READONLY_MEM
703 valid_flags |= KVM_MEM_READONLY;
704 #endif
705
706 if (mem->flags & ~valid_flags)
707 return -EINVAL;
708
709 return 0;
710 }
711
712 static struct kvm_memslots *install_new_memslots(struct kvm *kvm,
713 struct kvm_memslots *slots, struct kvm_memory_slot *new)
714 {
715 struct kvm_memslots *old_memslots = kvm->memslots;
716
717 update_memslots(slots, new, kvm->memslots->generation);
718 rcu_assign_pointer(kvm->memslots, slots);
719 synchronize_srcu_expedited(&kvm->srcu);
720
721 kvm_arch_memslots_updated(kvm);
722
723 return old_memslots;
724 }
725
726 /*
727 * Allocate some memory and give it an address in the guest physical address
728 * space.
729 *
730 * Discontiguous memory is allowed, mostly for framebuffers.
731 *
732 * Must be called holding mmap_sem for write.
733 */
734 int __kvm_set_memory_region(struct kvm *kvm,
735 struct kvm_userspace_memory_region *mem)
736 {
737 int r;
738 gfn_t base_gfn;
739 unsigned long npages;
740 struct kvm_memory_slot *slot;
741 struct kvm_memory_slot old, new;
742 struct kvm_memslots *slots = NULL, *old_memslots;
743 enum kvm_mr_change change;
744
745 r = check_memory_region_flags(mem);
746 if (r)
747 goto out;
748
749 r = -EINVAL;
750 /* General sanity checks */
751 if (mem->memory_size & (PAGE_SIZE - 1))
752 goto out;
753 if (mem->guest_phys_addr & (PAGE_SIZE - 1))
754 goto out;
755 /* We can read the guest memory with __xxx_user() later on. */
756 if ((mem->slot < KVM_USER_MEM_SLOTS) &&
757 ((mem->userspace_addr & (PAGE_SIZE - 1)) ||
758 !access_ok(VERIFY_WRITE,
759 (void __user *)(unsigned long)mem->userspace_addr,
760 mem->memory_size)))
761 goto out;
762 if (mem->slot >= KVM_MEM_SLOTS_NUM)
763 goto out;
764 if (mem->guest_phys_addr + mem->memory_size < mem->guest_phys_addr)
765 goto out;
766
767 slot = id_to_memslot(kvm->memslots, mem->slot);
768 base_gfn = mem->guest_phys_addr >> PAGE_SHIFT;
769 npages = mem->memory_size >> PAGE_SHIFT;
770
771 r = -EINVAL;
772 if (npages > KVM_MEM_MAX_NR_PAGES)
773 goto out;
774
775 if (!npages)
776 mem->flags &= ~KVM_MEM_LOG_DIRTY_PAGES;
777
778 new = old = *slot;
779
780 new.id = mem->slot;
781 new.base_gfn = base_gfn;
782 new.npages = npages;
783 new.flags = mem->flags;
784
785 r = -EINVAL;
786 if (npages) {
787 if (!old.npages)
788 change = KVM_MR_CREATE;
789 else { /* Modify an existing slot. */
790 if ((mem->userspace_addr != old.userspace_addr) ||
791 (npages != old.npages) ||
792 ((new.flags ^ old.flags) & KVM_MEM_READONLY))
793 goto out;
794
795 if (base_gfn != old.base_gfn)
796 change = KVM_MR_MOVE;
797 else if (new.flags != old.flags)
798 change = KVM_MR_FLAGS_ONLY;
799 else { /* Nothing to change. */
800 r = 0;
801 goto out;
802 }
803 }
804 } else if (old.npages) {
805 change = KVM_MR_DELETE;
806 } else /* Modify a non-existent slot: disallowed. */
807 goto out;
808
809 if ((change == KVM_MR_CREATE) || (change == KVM_MR_MOVE)) {
810 /* Check for overlaps */
811 r = -EEXIST;
812 kvm_for_each_memslot(slot, kvm->memslots) {
813 if ((slot->id >= KVM_USER_MEM_SLOTS) ||
814 (slot->id == mem->slot))
815 continue;
816 if (!((base_gfn + npages <= slot->base_gfn) ||
817 (base_gfn >= slot->base_gfn + slot->npages)))
818 goto out;
819 }
820 }
821
822 /* Free page dirty bitmap if unneeded */
823 if (!(new.flags & KVM_MEM_LOG_DIRTY_PAGES))
824 new.dirty_bitmap = NULL;
825
826 r = -ENOMEM;
827 if (change == KVM_MR_CREATE) {
828 new.userspace_addr = mem->userspace_addr;
829
830 if (kvm_arch_create_memslot(kvm, &new, npages))
831 goto out_free;
832 }
833
834 /* Allocate page dirty bitmap if needed */
835 if ((new.flags & KVM_MEM_LOG_DIRTY_PAGES) && !new.dirty_bitmap) {
836 if (kvm_create_dirty_bitmap(&new) < 0)
837 goto out_free;
838 }
839
840 if ((change == KVM_MR_DELETE) || (change == KVM_MR_MOVE)) {
841 r = -ENOMEM;
842 slots = kmemdup(kvm->memslots, sizeof(struct kvm_memslots),
843 GFP_KERNEL);
844 if (!slots)
845 goto out_free;
846 slot = id_to_memslot(slots, mem->slot);
847 slot->flags |= KVM_MEMSLOT_INVALID;
848
849 old_memslots = install_new_memslots(kvm, slots, NULL);
850
851 /* slot was deleted or moved, clear iommu mapping */
852 kvm_iommu_unmap_pages(kvm, &old);
853 /* From this point no new shadow pages pointing to a deleted,
854 * or moved, memslot will be created.
855 *
856 * validation of sp->gfn happens in:
857 * - gfn_to_hva (kvm_read_guest, gfn_to_pfn)
858 * - kvm_is_visible_gfn (mmu_check_roots)
859 */
860 kvm_arch_flush_shadow_memslot(kvm, slot);
861 slots = old_memslots;
862 }
863
864 r = kvm_arch_prepare_memory_region(kvm, &new, mem, change);
865 if (r)
866 goto out_slots;
867
868 r = -ENOMEM;
869 /*
870 * We can re-use the old_memslots from above, the only difference
871 * from the currently installed memslots is the invalid flag. This
872 * will get overwritten by update_memslots anyway.
873 */
874 if (!slots) {
875 slots = kmemdup(kvm->memslots, sizeof(struct kvm_memslots),
876 GFP_KERNEL);
877 if (!slots)
878 goto out_free;
879 }
880
881 /* actual memory is freed via old in kvm_free_physmem_slot below */
882 if (change == KVM_MR_DELETE) {
883 new.dirty_bitmap = NULL;
884 memset(&new.arch, 0, sizeof(new.arch));
885 }
886
887 old_memslots = install_new_memslots(kvm, slots, &new);
888
889 kvm_arch_commit_memory_region(kvm, mem, &old, change);
890
891 kvm_free_physmem_slot(kvm, &old, &new);
892 kfree(old_memslots);
893
894 /*
895 * IOMMU mapping: New slots need to be mapped. Old slots need to be
896 * un-mapped and re-mapped if their base changes. Since base change
897 * unmapping is handled above with slot deletion, mapping alone is
898 * needed here. Anything else the iommu might care about for existing
899 * slots (size changes, userspace addr changes and read-only flag
900 * changes) is disallowed above, so any other attribute changes getting
901 * here can be skipped.
902 */
903 if ((change == KVM_MR_CREATE) || (change == KVM_MR_MOVE)) {
904 r = kvm_iommu_map_pages(kvm, &new);
905 return r;
906 }
907
908 return 0;
909
910 out_slots:
911 kfree(slots);
912 out_free:
913 kvm_free_physmem_slot(kvm, &new, &old);
914 out:
915 return r;
916 }
917 EXPORT_SYMBOL_GPL(__kvm_set_memory_region);
918
919 int kvm_set_memory_region(struct kvm *kvm,
920 struct kvm_userspace_memory_region *mem)
921 {
922 int r;
923
924 mutex_lock(&kvm->slots_lock);
925 r = __kvm_set_memory_region(kvm, mem);
926 mutex_unlock(&kvm->slots_lock);
927 return r;
928 }
929 EXPORT_SYMBOL_GPL(kvm_set_memory_region);
930
931 static int kvm_vm_ioctl_set_memory_region(struct kvm *kvm,
932 struct kvm_userspace_memory_region *mem)
933 {
934 if (mem->slot >= KVM_USER_MEM_SLOTS)
935 return -EINVAL;
936 return kvm_set_memory_region(kvm, mem);
937 }
938
939 int kvm_get_dirty_log(struct kvm *kvm,
940 struct kvm_dirty_log *log, int *is_dirty)
941 {
942 struct kvm_memory_slot *memslot;
943 int r, i;
944 unsigned long n;
945 unsigned long any = 0;
946
947 r = -EINVAL;
948 if (log->slot >= KVM_USER_MEM_SLOTS)
949 goto out;
950
951 memslot = id_to_memslot(kvm->memslots, log->slot);
952 r = -ENOENT;
953 if (!memslot->dirty_bitmap)
954 goto out;
955
956 n = kvm_dirty_bitmap_bytes(memslot);
957
958 for (i = 0; !any && i < n/sizeof(long); ++i)
959 any = memslot->dirty_bitmap[i];
960
961 r = -EFAULT;
962 if (copy_to_user(log->dirty_bitmap, memslot->dirty_bitmap, n))
963 goto out;
964
965 if (any)
966 *is_dirty = 1;
967
968 r = 0;
969 out:
970 return r;
971 }
972 EXPORT_SYMBOL_GPL(kvm_get_dirty_log);
973
974 bool kvm_largepages_enabled(void)
975 {
976 return largepages_enabled;
977 }
978
979 void kvm_disable_largepages(void)
980 {
981 largepages_enabled = false;
982 }
983 EXPORT_SYMBOL_GPL(kvm_disable_largepages);
984
985 struct kvm_memory_slot *gfn_to_memslot(struct kvm *kvm, gfn_t gfn)
986 {
987 return __gfn_to_memslot(kvm_memslots(kvm), gfn);
988 }
989 EXPORT_SYMBOL_GPL(gfn_to_memslot);
990
991 int kvm_is_visible_gfn(struct kvm *kvm, gfn_t gfn)
992 {
993 struct kvm_memory_slot *memslot = gfn_to_memslot(kvm, gfn);
994
995 if (!memslot || memslot->id >= KVM_USER_MEM_SLOTS ||
996 memslot->flags & KVM_MEMSLOT_INVALID)
997 return 0;
998
999 return 1;
1000 }
1001 EXPORT_SYMBOL_GPL(kvm_is_visible_gfn);
1002
1003 unsigned long kvm_host_page_size(struct kvm *kvm, gfn_t gfn)
1004 {
1005 struct vm_area_struct *vma;
1006 unsigned long addr, size;
1007
1008 size = PAGE_SIZE;
1009
1010 addr = gfn_to_hva(kvm, gfn);
1011 if (kvm_is_error_hva(addr))
1012 return PAGE_SIZE;
1013
1014 down_read(&current->mm->mmap_sem);
1015 vma = find_vma(current->mm, addr);
1016 if (!vma)
1017 goto out;
1018
1019 size = vma_kernel_pagesize(vma);
1020
1021 out:
1022 up_read(&current->mm->mmap_sem);
1023
1024 return size;
1025 }
1026
1027 static bool memslot_is_readonly(struct kvm_memory_slot *slot)
1028 {
1029 return slot->flags & KVM_MEM_READONLY;
1030 }
1031
1032 static unsigned long __gfn_to_hva_many(struct kvm_memory_slot *slot, gfn_t gfn,
1033 gfn_t *nr_pages, bool write)
1034 {
1035 if (!slot || slot->flags & KVM_MEMSLOT_INVALID)
1036 return KVM_HVA_ERR_BAD;
1037
1038 if (memslot_is_readonly(slot) && write)
1039 return KVM_HVA_ERR_RO_BAD;
1040
1041 if (nr_pages)
1042 *nr_pages = slot->npages - (gfn - slot->base_gfn);
1043
1044 return __gfn_to_hva_memslot(slot, gfn);
1045 }
1046
1047 static unsigned long gfn_to_hva_many(struct kvm_memory_slot *slot, gfn_t gfn,
1048 gfn_t *nr_pages)
1049 {
1050 return __gfn_to_hva_many(slot, gfn, nr_pages, true);
1051 }
1052
1053 unsigned long gfn_to_hva_memslot(struct kvm_memory_slot *slot,
1054 gfn_t gfn)
1055 {
1056 return gfn_to_hva_many(slot, gfn, NULL);
1057 }
1058 EXPORT_SYMBOL_GPL(gfn_to_hva_memslot);
1059
1060 unsigned long gfn_to_hva(struct kvm *kvm, gfn_t gfn)
1061 {
1062 return gfn_to_hva_many(gfn_to_memslot(kvm, gfn), gfn, NULL);
1063 }
1064 EXPORT_SYMBOL_GPL(gfn_to_hva);
1065
1066 /*
1067 * If writable is set to false, the hva returned by this function is only
1068 * allowed to be read.
1069 */
1070 unsigned long gfn_to_hva_prot(struct kvm *kvm, gfn_t gfn, bool *writable)
1071 {
1072 struct kvm_memory_slot *slot = gfn_to_memslot(kvm, gfn);
1073 unsigned long hva = __gfn_to_hva_many(slot, gfn, NULL, false);
1074
1075 if (!kvm_is_error_hva(hva) && writable)
1076 *writable = !memslot_is_readonly(slot);
1077
1078 return hva;
1079 }
1080
1081 static int kvm_read_hva(void *data, void __user *hva, int len)
1082 {
1083 return __copy_from_user(data, hva, len);
1084 }
1085
1086 static int kvm_read_hva_atomic(void *data, void __user *hva, int len)
1087 {
1088 return __copy_from_user_inatomic(data, hva, len);
1089 }
1090
1091 static int get_user_page_nowait(struct task_struct *tsk, struct mm_struct *mm,
1092 unsigned long start, int write, struct page **page)
1093 {
1094 int flags = FOLL_TOUCH | FOLL_NOWAIT | FOLL_HWPOISON | FOLL_GET;
1095
1096 if (write)
1097 flags |= FOLL_WRITE;
1098
1099 return __get_user_pages(tsk, mm, start, 1, flags, page, NULL, NULL);
1100 }
1101
1102 static inline int check_user_page_hwpoison(unsigned long addr)
1103 {
1104 int rc, flags = FOLL_TOUCH | FOLL_HWPOISON | FOLL_WRITE;
1105
1106 rc = __get_user_pages(current, current->mm, addr, 1,
1107 flags, NULL, NULL, NULL);
1108 return rc == -EHWPOISON;
1109 }
1110
1111 /*
1112 * The atomic path to get the writable pfn which will be stored in @pfn,
1113 * true indicates success, otherwise false is returned.
1114 */
1115 static bool hva_to_pfn_fast(unsigned long addr, bool atomic, bool *async,
1116 bool write_fault, bool *writable, pfn_t *pfn)
1117 {
1118 struct page *page[1];
1119 int npages;
1120
1121 if (!(async || atomic))
1122 return false;
1123
1124 /*
1125 * Fast pin a writable pfn only if it is a write fault request
1126 * or the caller allows to map a writable pfn for a read fault
1127 * request.
1128 */
1129 if (!(write_fault || writable))
1130 return false;
1131
1132 npages = __get_user_pages_fast(addr, 1, 1, page);
1133 if (npages == 1) {
1134 *pfn = page_to_pfn(page[0]);
1135
1136 if (writable)
1137 *writable = true;
1138 return true;
1139 }
1140
1141 return false;
1142 }
1143
1144 /*
1145 * The slow path to get the pfn of the specified host virtual address,
1146 * 1 indicates success, -errno is returned if error is detected.
1147 */
1148 static int hva_to_pfn_slow(unsigned long addr, bool *async, bool write_fault,
1149 bool *writable, pfn_t *pfn)
1150 {
1151 struct page *page[1];
1152 int npages = 0;
1153
1154 might_sleep();
1155
1156 if (writable)
1157 *writable = write_fault;
1158
1159 if (async) {
1160 down_read(&current->mm->mmap_sem);
1161 npages = get_user_page_nowait(current, current->mm,
1162 addr, write_fault, page);
1163 up_read(&current->mm->mmap_sem);
1164 } else
1165 npages = get_user_pages_fast(addr, 1, write_fault,
1166 page);
1167 if (npages != 1)
1168 return npages;
1169
1170 /* map read fault as writable if possible */
1171 if (unlikely(!write_fault) && writable) {
1172 struct page *wpage[1];
1173
1174 npages = __get_user_pages_fast(addr, 1, 1, wpage);
1175 if (npages == 1) {
1176 *writable = true;
1177 put_page(page[0]);
1178 page[0] = wpage[0];
1179 }
1180
1181 npages = 1;
1182 }
1183 *pfn = page_to_pfn(page[0]);
1184 return npages;
1185 }
1186
1187 static bool vma_is_valid(struct vm_area_struct *vma, bool write_fault)
1188 {
1189 if (unlikely(!(vma->vm_flags & VM_READ)))
1190 return false;
1191
1192 if (write_fault && (unlikely(!(vma->vm_flags & VM_WRITE))))
1193 return false;
1194
1195 return true;
1196 }
1197
1198 /*
1199 * Pin guest page in memory and return its pfn.
1200 * @addr: host virtual address which maps memory to the guest
1201 * @atomic: whether this function can sleep
1202 * @async: whether this function need to wait IO complete if the
1203 * host page is not in the memory
1204 * @write_fault: whether we should get a writable host page
1205 * @writable: whether it allows to map a writable host page for !@write_fault
1206 *
1207 * The function will map a writable host page for these two cases:
1208 * 1): @write_fault = true
1209 * 2): @write_fault = false && @writable, @writable will tell the caller
1210 * whether the mapping is writable.
1211 */
1212 static pfn_t hva_to_pfn(unsigned long addr, bool atomic, bool *async,
1213 bool write_fault, bool *writable)
1214 {
1215 struct vm_area_struct *vma;
1216 pfn_t pfn = 0;
1217 int npages;
1218
1219 /* we can do it either atomically or asynchronously, not both */
1220 BUG_ON(atomic && async);
1221
1222 if (hva_to_pfn_fast(addr, atomic, async, write_fault, writable, &pfn))
1223 return pfn;
1224
1225 if (atomic)
1226 return KVM_PFN_ERR_FAULT;
1227
1228 npages = hva_to_pfn_slow(addr, async, write_fault, writable, &pfn);
1229 if (npages == 1)
1230 return pfn;
1231
1232 down_read(&current->mm->mmap_sem);
1233 if (npages == -EHWPOISON ||
1234 (!async && check_user_page_hwpoison(addr))) {
1235 pfn = KVM_PFN_ERR_HWPOISON;
1236 goto exit;
1237 }
1238
1239 vma = find_vma_intersection(current->mm, addr, addr + 1);
1240
1241 if (vma == NULL)
1242 pfn = KVM_PFN_ERR_FAULT;
1243 else if ((vma->vm_flags & VM_PFNMAP)) {
1244 pfn = ((addr - vma->vm_start) >> PAGE_SHIFT) +
1245 vma->vm_pgoff;
1246 BUG_ON(!kvm_is_mmio_pfn(pfn));
1247 } else {
1248 if (async && vma_is_valid(vma, write_fault))
1249 *async = true;
1250 pfn = KVM_PFN_ERR_FAULT;
1251 }
1252 exit:
1253 up_read(&current->mm->mmap_sem);
1254 return pfn;
1255 }
1256
1257 static pfn_t
1258 __gfn_to_pfn_memslot(struct kvm_memory_slot *slot, gfn_t gfn, bool atomic,
1259 bool *async, bool write_fault, bool *writable)
1260 {
1261 unsigned long addr = __gfn_to_hva_many(slot, gfn, NULL, write_fault);
1262
1263 if (addr == KVM_HVA_ERR_RO_BAD)
1264 return KVM_PFN_ERR_RO_FAULT;
1265
1266 if (kvm_is_error_hva(addr))
1267 return KVM_PFN_NOSLOT;
1268
1269 /* Do not map writable pfn in the readonly memslot. */
1270 if (writable && memslot_is_readonly(slot)) {
1271 *writable = false;
1272 writable = NULL;
1273 }
1274
1275 return hva_to_pfn(addr, atomic, async, write_fault,
1276 writable);
1277 }
1278
1279 static pfn_t __gfn_to_pfn(struct kvm *kvm, gfn_t gfn, bool atomic, bool *async,
1280 bool write_fault, bool *writable)
1281 {
1282 struct kvm_memory_slot *slot;
1283
1284 if (async)
1285 *async = false;
1286
1287 slot = gfn_to_memslot(kvm, gfn);
1288
1289 return __gfn_to_pfn_memslot(slot, gfn, atomic, async, write_fault,
1290 writable);
1291 }
1292
1293 pfn_t gfn_to_pfn_atomic(struct kvm *kvm, gfn_t gfn)
1294 {
1295 return __gfn_to_pfn(kvm, gfn, true, NULL, true, NULL);
1296 }
1297 EXPORT_SYMBOL_GPL(gfn_to_pfn_atomic);
1298
1299 pfn_t gfn_to_pfn_async(struct kvm *kvm, gfn_t gfn, bool *async,
1300 bool write_fault, bool *writable)
1301 {
1302 return __gfn_to_pfn(kvm, gfn, false, async, write_fault, writable);
1303 }
1304 EXPORT_SYMBOL_GPL(gfn_to_pfn_async);
1305
1306 pfn_t gfn_to_pfn(struct kvm *kvm, gfn_t gfn)
1307 {
1308 return __gfn_to_pfn(kvm, gfn, false, NULL, true, NULL);
1309 }
1310 EXPORT_SYMBOL_GPL(gfn_to_pfn);
1311
1312 pfn_t gfn_to_pfn_prot(struct kvm *kvm, gfn_t gfn, bool write_fault,
1313 bool *writable)
1314 {
1315 return __gfn_to_pfn(kvm, gfn, false, NULL, write_fault, writable);
1316 }
1317 EXPORT_SYMBOL_GPL(gfn_to_pfn_prot);
1318
1319 pfn_t gfn_to_pfn_memslot(struct kvm_memory_slot *slot, gfn_t gfn)
1320 {
1321 return __gfn_to_pfn_memslot(slot, gfn, false, NULL, true, NULL);
1322 }
1323
1324 pfn_t gfn_to_pfn_memslot_atomic(struct kvm_memory_slot *slot, gfn_t gfn)
1325 {
1326 return __gfn_to_pfn_memslot(slot, gfn, true, NULL, true, NULL);
1327 }
1328 EXPORT_SYMBOL_GPL(gfn_to_pfn_memslot_atomic);
1329
1330 int gfn_to_page_many_atomic(struct kvm *kvm, gfn_t gfn, struct page **pages,
1331 int nr_pages)
1332 {
1333 unsigned long addr;
1334 gfn_t entry;
1335
1336 addr = gfn_to_hva_many(gfn_to_memslot(kvm, gfn), gfn, &entry);
1337 if (kvm_is_error_hva(addr))
1338 return -1;
1339
1340 if (entry < nr_pages)
1341 return 0;
1342
1343 return __get_user_pages_fast(addr, nr_pages, 1, pages);
1344 }
1345 EXPORT_SYMBOL_GPL(gfn_to_page_many_atomic);
1346
1347 static struct page *kvm_pfn_to_page(pfn_t pfn)
1348 {
1349 if (is_error_noslot_pfn(pfn))
1350 return KVM_ERR_PTR_BAD_PAGE;
1351
1352 if (kvm_is_mmio_pfn(pfn)) {
1353 WARN_ON(1);
1354 return KVM_ERR_PTR_BAD_PAGE;
1355 }
1356
1357 return pfn_to_page(pfn);
1358 }
1359
1360 struct page *gfn_to_page(struct kvm *kvm, gfn_t gfn)
1361 {
1362 pfn_t pfn;
1363
1364 pfn = gfn_to_pfn(kvm, gfn);
1365
1366 return kvm_pfn_to_page(pfn);
1367 }
1368
1369 EXPORT_SYMBOL_GPL(gfn_to_page);
1370
1371 void kvm_release_page_clean(struct page *page)
1372 {
1373 WARN_ON(is_error_page(page));
1374
1375 kvm_release_pfn_clean(page_to_pfn(page));
1376 }
1377 EXPORT_SYMBOL_GPL(kvm_release_page_clean);
1378
1379 void kvm_release_pfn_clean(pfn_t pfn)
1380 {
1381 if (!is_error_noslot_pfn(pfn) && !kvm_is_mmio_pfn(pfn))
1382 put_page(pfn_to_page(pfn));
1383 }
1384 EXPORT_SYMBOL_GPL(kvm_release_pfn_clean);
1385
1386 void kvm_release_page_dirty(struct page *page)
1387 {
1388 WARN_ON(is_error_page(page));
1389
1390 kvm_release_pfn_dirty(page_to_pfn(page));
1391 }
1392 EXPORT_SYMBOL_GPL(kvm_release_page_dirty);
1393
1394 static void kvm_release_pfn_dirty(pfn_t pfn)
1395 {
1396 kvm_set_pfn_dirty(pfn);
1397 kvm_release_pfn_clean(pfn);
1398 }
1399
1400 void kvm_set_pfn_dirty(pfn_t pfn)
1401 {
1402 if (!kvm_is_mmio_pfn(pfn)) {
1403 struct page *page = pfn_to_page(pfn);
1404 if (!PageReserved(page))
1405 SetPageDirty(page);
1406 }
1407 }
1408 EXPORT_SYMBOL_GPL(kvm_set_pfn_dirty);
1409
1410 void kvm_set_pfn_accessed(pfn_t pfn)
1411 {
1412 if (!kvm_is_mmio_pfn(pfn))
1413 mark_page_accessed(pfn_to_page(pfn));
1414 }
1415 EXPORT_SYMBOL_GPL(kvm_set_pfn_accessed);
1416
1417 void kvm_get_pfn(pfn_t pfn)
1418 {
1419 if (!kvm_is_mmio_pfn(pfn))
1420 get_page(pfn_to_page(pfn));
1421 }
1422 EXPORT_SYMBOL_GPL(kvm_get_pfn);
1423
1424 static int next_segment(unsigned long len, int offset)
1425 {
1426 if (len > PAGE_SIZE - offset)
1427 return PAGE_SIZE - offset;
1428 else
1429 return len;
1430 }
1431
1432 int kvm_read_guest_page(struct kvm *kvm, gfn_t gfn, void *data, int offset,
1433 int len)
1434 {
1435 int r;
1436 unsigned long addr;
1437
1438 addr = gfn_to_hva_prot(kvm, gfn, NULL);
1439 if (kvm_is_error_hva(addr))
1440 return -EFAULT;
1441 r = kvm_read_hva(data, (void __user *)addr + offset, len);
1442 if (r)
1443 return -EFAULT;
1444 return 0;
1445 }
1446 EXPORT_SYMBOL_GPL(kvm_read_guest_page);
1447
1448 int kvm_read_guest(struct kvm *kvm, gpa_t gpa, void *data, unsigned long len)
1449 {
1450 gfn_t gfn = gpa >> PAGE_SHIFT;
1451 int seg;
1452 int offset = offset_in_page(gpa);
1453 int ret;
1454
1455 while ((seg = next_segment(len, offset)) != 0) {
1456 ret = kvm_read_guest_page(kvm, gfn, data, offset, seg);
1457 if (ret < 0)
1458 return ret;
1459 offset = 0;
1460 len -= seg;
1461 data += seg;
1462 ++gfn;
1463 }
1464 return 0;
1465 }
1466 EXPORT_SYMBOL_GPL(kvm_read_guest);
1467
1468 int kvm_read_guest_atomic(struct kvm *kvm, gpa_t gpa, void *data,
1469 unsigned long len)
1470 {
1471 int r;
1472 unsigned long addr;
1473 gfn_t gfn = gpa >> PAGE_SHIFT;
1474 int offset = offset_in_page(gpa);
1475
1476 addr = gfn_to_hva_prot(kvm, gfn, NULL);
1477 if (kvm_is_error_hva(addr))
1478 return -EFAULT;
1479 pagefault_disable();
1480 r = kvm_read_hva_atomic(data, (void __user *)addr + offset, len);
1481 pagefault_enable();
1482 if (r)
1483 return -EFAULT;
1484 return 0;
1485 }
1486 EXPORT_SYMBOL(kvm_read_guest_atomic);
1487
1488 int kvm_write_guest_page(struct kvm *kvm, gfn_t gfn, const void *data,
1489 int offset, int len)
1490 {
1491 int r;
1492 unsigned long addr;
1493
1494 addr = gfn_to_hva(kvm, gfn);
1495 if (kvm_is_error_hva(addr))
1496 return -EFAULT;
1497 r = __copy_to_user((void __user *)addr + offset, data, len);
1498 if (r)
1499 return -EFAULT;
1500 mark_page_dirty(kvm, gfn);
1501 return 0;
1502 }
1503 EXPORT_SYMBOL_GPL(kvm_write_guest_page);
1504
1505 int kvm_write_guest(struct kvm *kvm, gpa_t gpa, const void *data,
1506 unsigned long len)
1507 {
1508 gfn_t gfn = gpa >> PAGE_SHIFT;
1509 int seg;
1510 int offset = offset_in_page(gpa);
1511 int ret;
1512
1513 while ((seg = next_segment(len, offset)) != 0) {
1514 ret = kvm_write_guest_page(kvm, gfn, data, offset, seg);
1515 if (ret < 0)
1516 return ret;
1517 offset = 0;
1518 len -= seg;
1519 data += seg;
1520 ++gfn;
1521 }
1522 return 0;
1523 }
1524
1525 int kvm_gfn_to_hva_cache_init(struct kvm *kvm, struct gfn_to_hva_cache *ghc,
1526 gpa_t gpa, unsigned long len)
1527 {
1528 struct kvm_memslots *slots = kvm_memslots(kvm);
1529 int offset = offset_in_page(gpa);
1530 gfn_t start_gfn = gpa >> PAGE_SHIFT;
1531 gfn_t end_gfn = (gpa + len - 1) >> PAGE_SHIFT;
1532 gfn_t nr_pages_needed = end_gfn - start_gfn + 1;
1533 gfn_t nr_pages_avail;
1534
1535 ghc->gpa = gpa;
1536 ghc->generation = slots->generation;
1537 ghc->len = len;
1538 ghc->memslot = gfn_to_memslot(kvm, start_gfn);
1539 ghc->hva = gfn_to_hva_many(ghc->memslot, start_gfn, &nr_pages_avail);
1540 if (!kvm_is_error_hva(ghc->hva) && nr_pages_avail >= nr_pages_needed) {
1541 ghc->hva += offset;
1542 } else {
1543 /*
1544 * If the requested region crosses two memslots, we still
1545 * verify that the entire region is valid here.
1546 */
1547 while (start_gfn <= end_gfn) {
1548 ghc->memslot = gfn_to_memslot(kvm, start_gfn);
1549 ghc->hva = gfn_to_hva_many(ghc->memslot, start_gfn,
1550 &nr_pages_avail);
1551 if (kvm_is_error_hva(ghc->hva))
1552 return -EFAULT;
1553 start_gfn += nr_pages_avail;
1554 }
1555 /* Use the slow path for cross page reads and writes. */
1556 ghc->memslot = NULL;
1557 }
1558 return 0;
1559 }
1560 EXPORT_SYMBOL_GPL(kvm_gfn_to_hva_cache_init);
1561
1562 int kvm_write_guest_cached(struct kvm *kvm, struct gfn_to_hva_cache *ghc,
1563 void *data, unsigned long len)
1564 {
1565 struct kvm_memslots *slots = kvm_memslots(kvm);
1566 int r;
1567
1568 BUG_ON(len > ghc->len);
1569
1570 if (slots->generation != ghc->generation)
1571 kvm_gfn_to_hva_cache_init(kvm, ghc, ghc->gpa, ghc->len);
1572
1573 if (unlikely(!ghc->memslot))
1574 return kvm_write_guest(kvm, ghc->gpa, data, len);
1575
1576 if (kvm_is_error_hva(ghc->hva))
1577 return -EFAULT;
1578
1579 r = __copy_to_user((void __user *)ghc->hva, data, len);
1580 if (r)
1581 return -EFAULT;
1582 mark_page_dirty_in_slot(kvm, ghc->memslot, ghc->gpa >> PAGE_SHIFT);
1583
1584 return 0;
1585 }
1586 EXPORT_SYMBOL_GPL(kvm_write_guest_cached);
1587
1588 int kvm_read_guest_cached(struct kvm *kvm, struct gfn_to_hva_cache *ghc,
1589 void *data, unsigned long len)
1590 {
1591 struct kvm_memslots *slots = kvm_memslots(kvm);
1592 int r;
1593
1594 BUG_ON(len > ghc->len);
1595
1596 if (slots->generation != ghc->generation)
1597 kvm_gfn_to_hva_cache_init(kvm, ghc, ghc->gpa, ghc->len);
1598
1599 if (unlikely(!ghc->memslot))
1600 return kvm_read_guest(kvm, ghc->gpa, data, len);
1601
1602 if (kvm_is_error_hva(ghc->hva))
1603 return -EFAULT;
1604
1605 r = __copy_from_user(data, (void __user *)ghc->hva, len);
1606 if (r)
1607 return -EFAULT;
1608
1609 return 0;
1610 }
1611 EXPORT_SYMBOL_GPL(kvm_read_guest_cached);
1612
1613 int kvm_clear_guest_page(struct kvm *kvm, gfn_t gfn, int offset, int len)
1614 {
1615 const void *zero_page = (const void *) __va(page_to_phys(ZERO_PAGE(0)));
1616
1617 return kvm_write_guest_page(kvm, gfn, zero_page, offset, len);
1618 }
1619 EXPORT_SYMBOL_GPL(kvm_clear_guest_page);
1620
1621 int kvm_clear_guest(struct kvm *kvm, gpa_t gpa, unsigned long len)
1622 {
1623 gfn_t gfn = gpa >> PAGE_SHIFT;
1624 int seg;
1625 int offset = offset_in_page(gpa);
1626 int ret;
1627
1628 while ((seg = next_segment(len, offset)) != 0) {
1629 ret = kvm_clear_guest_page(kvm, gfn, offset, seg);
1630 if (ret < 0)
1631 return ret;
1632 offset = 0;
1633 len -= seg;
1634 ++gfn;
1635 }
1636 return 0;
1637 }
1638 EXPORT_SYMBOL_GPL(kvm_clear_guest);
1639
1640 static void mark_page_dirty_in_slot(struct kvm *kvm,
1641 struct kvm_memory_slot *memslot,
1642 gfn_t gfn)
1643 {
1644 if (memslot && memslot->dirty_bitmap) {
1645 unsigned long rel_gfn = gfn - memslot->base_gfn;
1646
1647 set_bit_le(rel_gfn, memslot->dirty_bitmap);
1648 }
1649 }
1650
1651 void mark_page_dirty(struct kvm *kvm, gfn_t gfn)
1652 {
1653 struct kvm_memory_slot *memslot;
1654
1655 memslot = gfn_to_memslot(kvm, gfn);
1656 mark_page_dirty_in_slot(kvm, memslot, gfn);
1657 }
1658 EXPORT_SYMBOL_GPL(mark_page_dirty);
1659
1660 /*
1661 * The vCPU has executed a HLT instruction with in-kernel mode enabled.
1662 */
1663 void kvm_vcpu_block(struct kvm_vcpu *vcpu)
1664 {
1665 DEFINE_WAIT(wait);
1666
1667 for (;;) {
1668 prepare_to_wait(&vcpu->wq, &wait, TASK_INTERRUPTIBLE);
1669
1670 if (kvm_arch_vcpu_runnable(vcpu)) {
1671 kvm_make_request(KVM_REQ_UNHALT, vcpu);
1672 break;
1673 }
1674 if (kvm_cpu_has_pending_timer(vcpu))
1675 break;
1676 if (signal_pending(current))
1677 break;
1678
1679 schedule();
1680 }
1681
1682 finish_wait(&vcpu->wq, &wait);
1683 }
1684 EXPORT_SYMBOL_GPL(kvm_vcpu_block);
1685
1686 #ifndef CONFIG_S390
1687 /*
1688 * Kick a sleeping VCPU, or a guest VCPU in guest mode, into host kernel mode.
1689 */
1690 void kvm_vcpu_kick(struct kvm_vcpu *vcpu)
1691 {
1692 int me;
1693 int cpu = vcpu->cpu;
1694 wait_queue_head_t *wqp;
1695
1696 wqp = kvm_arch_vcpu_wq(vcpu);
1697 if (waitqueue_active(wqp)) {
1698 wake_up_interruptible(wqp);
1699 ++vcpu->stat.halt_wakeup;
1700 }
1701
1702 me = get_cpu();
1703 if (cpu != me && (unsigned)cpu < nr_cpu_ids && cpu_online(cpu))
1704 if (kvm_arch_vcpu_should_kick(vcpu))
1705 smp_send_reschedule(cpu);
1706 put_cpu();
1707 }
1708 EXPORT_SYMBOL_GPL(kvm_vcpu_kick);
1709 #endif /* !CONFIG_S390 */
1710
1711 int kvm_vcpu_yield_to(struct kvm_vcpu *target)
1712 {
1713 struct pid *pid;
1714 struct task_struct *task = NULL;
1715 int ret = 0;
1716
1717 rcu_read_lock();
1718 pid = rcu_dereference(target->pid);
1719 if (pid)
1720 task = get_pid_task(target->pid, PIDTYPE_PID);
1721 rcu_read_unlock();
1722 if (!task)
1723 return ret;
1724 if (task->flags & PF_VCPU) {
1725 put_task_struct(task);
1726 return ret;
1727 }
1728 ret = yield_to(task, 1);
1729 put_task_struct(task);
1730
1731 return ret;
1732 }
1733 EXPORT_SYMBOL_GPL(kvm_vcpu_yield_to);
1734
1735 /*
1736 * Helper that checks whether a VCPU is eligible for directed yield.
1737 * Most eligible candidate to yield is decided by following heuristics:
1738 *
1739 * (a) VCPU which has not done pl-exit or cpu relax intercepted recently
1740 * (preempted lock holder), indicated by @in_spin_loop.
1741 * Set at the beiginning and cleared at the end of interception/PLE handler.
1742 *
1743 * (b) VCPU which has done pl-exit/ cpu relax intercepted but did not get
1744 * chance last time (mostly it has become eligible now since we have probably
1745 * yielded to lockholder in last iteration. This is done by toggling
1746 * @dy_eligible each time a VCPU checked for eligibility.)
1747 *
1748 * Yielding to a recently pl-exited/cpu relax intercepted VCPU before yielding
1749 * to preempted lock-holder could result in wrong VCPU selection and CPU
1750 * burning. Giving priority for a potential lock-holder increases lock
1751 * progress.
1752 *
1753 * Since algorithm is based on heuristics, accessing another VCPU data without
1754 * locking does not harm. It may result in trying to yield to same VCPU, fail
1755 * and continue with next VCPU and so on.
1756 */
1757 static bool kvm_vcpu_eligible_for_directed_yield(struct kvm_vcpu *vcpu)
1758 {
1759 #ifdef CONFIG_HAVE_KVM_CPU_RELAX_INTERCEPT
1760 bool eligible;
1761
1762 eligible = !vcpu->spin_loop.in_spin_loop ||
1763 (vcpu->spin_loop.in_spin_loop &&
1764 vcpu->spin_loop.dy_eligible);
1765
1766 if (vcpu->spin_loop.in_spin_loop)
1767 kvm_vcpu_set_dy_eligible(vcpu, !vcpu->spin_loop.dy_eligible);
1768
1769 return eligible;
1770 #else
1771 return true;
1772 #endif
1773 }
1774
1775 void kvm_vcpu_on_spin(struct kvm_vcpu *me)
1776 {
1777 struct kvm *kvm = me->kvm;
1778 struct kvm_vcpu *vcpu;
1779 int last_boosted_vcpu = me->kvm->last_boosted_vcpu;
1780 int yielded = 0;
1781 int try = 3;
1782 int pass;
1783 int i;
1784
1785 kvm_vcpu_set_in_spin_loop(me, true);
1786 /*
1787 * We boost the priority of a VCPU that is runnable but not
1788 * currently running, because it got preempted by something
1789 * else and called schedule in __vcpu_run. Hopefully that
1790 * VCPU is holding the lock that we need and will release it.
1791 * We approximate round-robin by starting at the last boosted VCPU.
1792 */
1793 for (pass = 0; pass < 2 && !yielded && try; pass++) {
1794 kvm_for_each_vcpu(i, vcpu, kvm) {
1795 if (!pass && i <= last_boosted_vcpu) {
1796 i = last_boosted_vcpu;
1797 continue;
1798 } else if (pass && i > last_boosted_vcpu)
1799 break;
1800 if (!ACCESS_ONCE(vcpu->preempted))
1801 continue;
1802 if (vcpu == me)
1803 continue;
1804 if (waitqueue_active(&vcpu->wq) && !kvm_arch_vcpu_runnable(vcpu))
1805 continue;
1806 if (!kvm_vcpu_eligible_for_directed_yield(vcpu))
1807 continue;
1808
1809 yielded = kvm_vcpu_yield_to(vcpu);
1810 if (yielded > 0) {
1811 kvm->last_boosted_vcpu = i;
1812 break;
1813 } else if (yielded < 0) {
1814 try--;
1815 if (!try)
1816 break;
1817 }
1818 }
1819 }
1820 kvm_vcpu_set_in_spin_loop(me, false);
1821
1822 /* Ensure vcpu is not eligible during next spinloop */
1823 kvm_vcpu_set_dy_eligible(me, false);
1824 }
1825 EXPORT_SYMBOL_GPL(kvm_vcpu_on_spin);
1826
1827 static int kvm_vcpu_fault(struct vm_area_struct *vma, struct vm_fault *vmf)
1828 {
1829 struct kvm_vcpu *vcpu = vma->vm_file->private_data;
1830 struct page *page;
1831
1832 if (vmf->pgoff == 0)
1833 page = virt_to_page(vcpu->run);
1834 #ifdef CONFIG_X86
1835 else if (vmf->pgoff == KVM_PIO_PAGE_OFFSET)
1836 page = virt_to_page(vcpu->arch.pio_data);
1837 #endif
1838 #ifdef KVM_COALESCED_MMIO_PAGE_OFFSET
1839 else if (vmf->pgoff == KVM_COALESCED_MMIO_PAGE_OFFSET)
1840 page = virt_to_page(vcpu->kvm->coalesced_mmio_ring);
1841 #endif
1842 else
1843 return kvm_arch_vcpu_fault(vcpu, vmf);
1844 get_page(page);
1845 vmf->page = page;
1846 return 0;
1847 }
1848
1849 static const struct vm_operations_struct kvm_vcpu_vm_ops = {
1850 .fault = kvm_vcpu_fault,
1851 };
1852
1853 static int kvm_vcpu_mmap(struct file *file, struct vm_area_struct *vma)
1854 {
1855 vma->vm_ops = &kvm_vcpu_vm_ops;
1856 return 0;
1857 }
1858
1859 static int kvm_vcpu_release(struct inode *inode, struct file *filp)
1860 {
1861 struct kvm_vcpu *vcpu = filp->private_data;
1862
1863 kvm_put_kvm(vcpu->kvm);
1864 return 0;
1865 }
1866
1867 static struct file_operations kvm_vcpu_fops = {
1868 .release = kvm_vcpu_release,
1869 .unlocked_ioctl = kvm_vcpu_ioctl,
1870 #ifdef CONFIG_COMPAT
1871 .compat_ioctl = kvm_vcpu_compat_ioctl,
1872 #endif
1873 .mmap = kvm_vcpu_mmap,
1874 .llseek = noop_llseek,
1875 };
1876
1877 /*
1878 * Allocates an inode for the vcpu.
1879 */
1880 static int create_vcpu_fd(struct kvm_vcpu *vcpu)
1881 {
1882 return anon_inode_getfd("kvm-vcpu", &kvm_vcpu_fops, vcpu, O_RDWR | O_CLOEXEC);
1883 }
1884
1885 /*
1886 * Creates some virtual cpus. Good luck creating more than one.
1887 */
1888 static int kvm_vm_ioctl_create_vcpu(struct kvm *kvm, u32 id)
1889 {
1890 int r;
1891 struct kvm_vcpu *vcpu, *v;
1892
1893 if (id >= KVM_MAX_VCPUS)
1894 return -EINVAL;
1895
1896 vcpu = kvm_arch_vcpu_create(kvm, id);
1897 if (IS_ERR(vcpu))
1898 return PTR_ERR(vcpu);
1899
1900 preempt_notifier_init(&vcpu->preempt_notifier, &kvm_preempt_ops);
1901
1902 r = kvm_arch_vcpu_setup(vcpu);
1903 if (r)
1904 goto vcpu_destroy;
1905
1906 mutex_lock(&kvm->lock);
1907 if (!kvm_vcpu_compatible(vcpu)) {
1908 r = -EINVAL;
1909 goto unlock_vcpu_destroy;
1910 }
1911 if (atomic_read(&kvm->online_vcpus) == KVM_MAX_VCPUS) {
1912 r = -EINVAL;
1913 goto unlock_vcpu_destroy;
1914 }
1915
1916 kvm_for_each_vcpu(r, v, kvm)
1917 if (v->vcpu_id == id) {
1918 r = -EEXIST;
1919 goto unlock_vcpu_destroy;
1920 }
1921
1922 BUG_ON(kvm->vcpus[atomic_read(&kvm->online_vcpus)]);
1923
1924 /* Now it's all set up, let userspace reach it */
1925 kvm_get_kvm(kvm);
1926 r = create_vcpu_fd(vcpu);
1927 if (r < 0) {
1928 kvm_put_kvm(kvm);
1929 goto unlock_vcpu_destroy;
1930 }
1931
1932 kvm->vcpus[atomic_read(&kvm->online_vcpus)] = vcpu;
1933 smp_wmb();
1934 atomic_inc(&kvm->online_vcpus);
1935
1936 mutex_unlock(&kvm->lock);
1937 kvm_arch_vcpu_postcreate(vcpu);
1938 return r;
1939
1940 unlock_vcpu_destroy:
1941 mutex_unlock(&kvm->lock);
1942 vcpu_destroy:
1943 kvm_arch_vcpu_destroy(vcpu);
1944 return r;
1945 }
1946
1947 static int kvm_vcpu_ioctl_set_sigmask(struct kvm_vcpu *vcpu, sigset_t *sigset)
1948 {
1949 if (sigset) {
1950 sigdelsetmask(sigset, sigmask(SIGKILL)|sigmask(SIGSTOP));
1951 vcpu->sigset_active = 1;
1952 vcpu->sigset = *sigset;
1953 } else
1954 vcpu->sigset_active = 0;
1955 return 0;
1956 }
1957
1958 static long kvm_vcpu_ioctl(struct file *filp,
1959 unsigned int ioctl, unsigned long arg)
1960 {
1961 struct kvm_vcpu *vcpu = filp->private_data;
1962 void __user *argp = (void __user *)arg;
1963 int r;
1964 struct kvm_fpu *fpu = NULL;
1965 struct kvm_sregs *kvm_sregs = NULL;
1966
1967 if (vcpu->kvm->mm != current->mm)
1968 return -EIO;
1969
1970 #if defined(CONFIG_S390) || defined(CONFIG_PPC) || defined(CONFIG_MIPS)
1971 /*
1972 * Special cases: vcpu ioctls that are asynchronous to vcpu execution,
1973 * so vcpu_load() would break it.
1974 */
1975 if (ioctl == KVM_S390_INTERRUPT || ioctl == KVM_INTERRUPT)
1976 return kvm_arch_vcpu_ioctl(filp, ioctl, arg);
1977 #endif
1978
1979
1980 r = vcpu_load(vcpu);
1981 if (r)
1982 return r;
1983 switch (ioctl) {
1984 case KVM_RUN:
1985 r = -EINVAL;
1986 if (arg)
1987 goto out;
1988 r = kvm_arch_vcpu_ioctl_run(vcpu, vcpu->run);
1989 trace_kvm_userspace_exit(vcpu->run->exit_reason, r);
1990 break;
1991 case KVM_GET_REGS: {
1992 struct kvm_regs *kvm_regs;
1993
1994 r = -ENOMEM;
1995 kvm_regs = kzalloc(sizeof(struct kvm_regs), GFP_KERNEL);
1996 if (!kvm_regs)
1997 goto out;
1998 r = kvm_arch_vcpu_ioctl_get_regs(vcpu, kvm_regs);
1999 if (r)
2000 goto out_free1;
2001 r = -EFAULT;
2002 if (copy_to_user(argp, kvm_regs, sizeof(struct kvm_regs)))
2003 goto out_free1;
2004 r = 0;
2005 out_free1:
2006 kfree(kvm_regs);
2007 break;
2008 }
2009 case KVM_SET_REGS: {
2010 struct kvm_regs *kvm_regs;
2011
2012 r = -ENOMEM;
2013 kvm_regs = memdup_user(argp, sizeof(*kvm_regs));
2014 if (IS_ERR(kvm_regs)) {
2015 r = PTR_ERR(kvm_regs);
2016 goto out;
2017 }
2018 r = kvm_arch_vcpu_ioctl_set_regs(vcpu, kvm_regs);
2019 kfree(kvm_regs);
2020 break;
2021 }
2022 case KVM_GET_SREGS: {
2023 kvm_sregs = kzalloc(sizeof(struct kvm_sregs), GFP_KERNEL);
2024 r = -ENOMEM;
2025 if (!kvm_sregs)
2026 goto out;
2027 r = kvm_arch_vcpu_ioctl_get_sregs(vcpu, kvm_sregs);
2028 if (r)
2029 goto out;
2030 r = -EFAULT;
2031 if (copy_to_user(argp, kvm_sregs, sizeof(struct kvm_sregs)))
2032 goto out;
2033 r = 0;
2034 break;
2035 }
2036 case KVM_SET_SREGS: {
2037 kvm_sregs = memdup_user(argp, sizeof(*kvm_sregs));
2038 if (IS_ERR(kvm_sregs)) {
2039 r = PTR_ERR(kvm_sregs);
2040 kvm_sregs = NULL;
2041 goto out;
2042 }
2043 r = kvm_arch_vcpu_ioctl_set_sregs(vcpu, kvm_sregs);
2044 break;
2045 }
2046 case KVM_GET_MP_STATE: {
2047 struct kvm_mp_state mp_state;
2048
2049 r = kvm_arch_vcpu_ioctl_get_mpstate(vcpu, &mp_state);
2050 if (r)
2051 goto out;
2052 r = -EFAULT;
2053 if (copy_to_user(argp, &mp_state, sizeof mp_state))
2054 goto out;
2055 r = 0;
2056 break;
2057 }
2058 case KVM_SET_MP_STATE: {
2059 struct kvm_mp_state mp_state;
2060
2061 r = -EFAULT;
2062 if (copy_from_user(&mp_state, argp, sizeof mp_state))
2063 goto out;
2064 r = kvm_arch_vcpu_ioctl_set_mpstate(vcpu, &mp_state);
2065 break;
2066 }
2067 case KVM_TRANSLATE: {
2068 struct kvm_translation tr;
2069
2070 r = -EFAULT;
2071 if (copy_from_user(&tr, argp, sizeof tr))
2072 goto out;
2073 r = kvm_arch_vcpu_ioctl_translate(vcpu, &tr);
2074 if (r)
2075 goto out;
2076 r = -EFAULT;
2077 if (copy_to_user(argp, &tr, sizeof tr))
2078 goto out;
2079 r = 0;
2080 break;
2081 }
2082 case KVM_SET_GUEST_DEBUG: {
2083 struct kvm_guest_debug dbg;
2084
2085 r = -EFAULT;
2086 if (copy_from_user(&dbg, argp, sizeof dbg))
2087 goto out;
2088 r = kvm_arch_vcpu_ioctl_set_guest_debug(vcpu, &dbg);
2089 break;
2090 }
2091 case KVM_SET_SIGNAL_MASK: {
2092 struct kvm_signal_mask __user *sigmask_arg = argp;
2093 struct kvm_signal_mask kvm_sigmask;
2094 sigset_t sigset, *p;
2095
2096 p = NULL;
2097 if (argp) {
2098 r = -EFAULT;
2099 if (copy_from_user(&kvm_sigmask, argp,
2100 sizeof kvm_sigmask))
2101 goto out;
2102 r = -EINVAL;
2103 if (kvm_sigmask.len != sizeof sigset)
2104 goto out;
2105 r = -EFAULT;
2106 if (copy_from_user(&sigset, sigmask_arg->sigset,
2107 sizeof sigset))
2108 goto out;
2109 p = &sigset;
2110 }
2111 r = kvm_vcpu_ioctl_set_sigmask(vcpu, p);
2112 break;
2113 }
2114 case KVM_GET_FPU: {
2115 fpu = kzalloc(sizeof(struct kvm_fpu), GFP_KERNEL);
2116 r = -ENOMEM;
2117 if (!fpu)
2118 goto out;
2119 r = kvm_arch_vcpu_ioctl_get_fpu(vcpu, fpu);
2120 if (r)
2121 goto out;
2122 r = -EFAULT;
2123 if (copy_to_user(argp, fpu, sizeof(struct kvm_fpu)))
2124 goto out;
2125 r = 0;
2126 break;
2127 }
2128 case KVM_SET_FPU: {
2129 fpu = memdup_user(argp, sizeof(*fpu));
2130 if (IS_ERR(fpu)) {
2131 r = PTR_ERR(fpu);
2132 fpu = NULL;
2133 goto out;
2134 }
2135 r = kvm_arch_vcpu_ioctl_set_fpu(vcpu, fpu);
2136 break;
2137 }
2138 default:
2139 r = kvm_arch_vcpu_ioctl(filp, ioctl, arg);
2140 }
2141 out:
2142 vcpu_put(vcpu);
2143 kfree(fpu);
2144 kfree(kvm_sregs);
2145 return r;
2146 }
2147
2148 #ifdef CONFIG_COMPAT
2149 static long kvm_vcpu_compat_ioctl(struct file *filp,
2150 unsigned int ioctl, unsigned long arg)
2151 {
2152 struct kvm_vcpu *vcpu = filp->private_data;
2153 void __user *argp = compat_ptr(arg);
2154 int r;
2155
2156 if (vcpu->kvm->mm != current->mm)
2157 return -EIO;
2158
2159 switch (ioctl) {
2160 case KVM_SET_SIGNAL_MASK: {
2161 struct kvm_signal_mask __user *sigmask_arg = argp;
2162 struct kvm_signal_mask kvm_sigmask;
2163 compat_sigset_t csigset;
2164 sigset_t sigset;
2165
2166 if (argp) {
2167 r = -EFAULT;
2168 if (copy_from_user(&kvm_sigmask, argp,
2169 sizeof kvm_sigmask))
2170 goto out;
2171 r = -EINVAL;
2172 if (kvm_sigmask.len != sizeof csigset)
2173 goto out;
2174 r = -EFAULT;
2175 if (copy_from_user(&csigset, sigmask_arg->sigset,
2176 sizeof csigset))
2177 goto out;
2178 sigset_from_compat(&sigset, &csigset);
2179 r = kvm_vcpu_ioctl_set_sigmask(vcpu, &sigset);
2180 } else
2181 r = kvm_vcpu_ioctl_set_sigmask(vcpu, NULL);
2182 break;
2183 }
2184 default:
2185 r = kvm_vcpu_ioctl(filp, ioctl, arg);
2186 }
2187
2188 out:
2189 return r;
2190 }
2191 #endif
2192
2193 static int kvm_device_ioctl_attr(struct kvm_device *dev,
2194 int (*accessor)(struct kvm_device *dev,
2195 struct kvm_device_attr *attr),
2196 unsigned long arg)
2197 {
2198 struct kvm_device_attr attr;
2199
2200 if (!accessor)
2201 return -EPERM;
2202
2203 if (copy_from_user(&attr, (void __user *)arg, sizeof(attr)))
2204 return -EFAULT;
2205
2206 return accessor(dev, &attr);
2207 }
2208
2209 static long kvm_device_ioctl(struct file *filp, unsigned int ioctl,
2210 unsigned long arg)
2211 {
2212 struct kvm_device *dev = filp->private_data;
2213
2214 switch (ioctl) {
2215 case KVM_SET_DEVICE_ATTR:
2216 return kvm_device_ioctl_attr(dev, dev->ops->set_attr, arg);
2217 case KVM_GET_DEVICE_ATTR:
2218 return kvm_device_ioctl_attr(dev, dev->ops->get_attr, arg);
2219 case KVM_HAS_DEVICE_ATTR:
2220 return kvm_device_ioctl_attr(dev, dev->ops->has_attr, arg);
2221 default:
2222 if (dev->ops->ioctl)
2223 return dev->ops->ioctl(dev, ioctl, arg);
2224
2225 return -ENOTTY;
2226 }
2227 }
2228
2229 static int kvm_device_release(struct inode *inode, struct file *filp)
2230 {
2231 struct kvm_device *dev = filp->private_data;
2232 struct kvm *kvm = dev->kvm;
2233
2234 kvm_put_kvm(kvm);
2235 return 0;
2236 }
2237
2238 static const struct file_operations kvm_device_fops = {
2239 .unlocked_ioctl = kvm_device_ioctl,
2240 #ifdef CONFIG_COMPAT
2241 .compat_ioctl = kvm_device_ioctl,
2242 #endif
2243 .release = kvm_device_release,
2244 };
2245
2246 struct kvm_device *kvm_device_from_filp(struct file *filp)
2247 {
2248 if (filp->f_op != &kvm_device_fops)
2249 return NULL;
2250
2251 return filp->private_data;
2252 }
2253
2254 static int kvm_ioctl_create_device(struct kvm *kvm,
2255 struct kvm_create_device *cd)
2256 {
2257 struct kvm_device_ops *ops = NULL;
2258 struct kvm_device *dev;
2259 bool test = cd->flags & KVM_CREATE_DEVICE_TEST;
2260 int ret;
2261
2262 switch (cd->type) {
2263 #ifdef CONFIG_KVM_MPIC
2264 case KVM_DEV_TYPE_FSL_MPIC_20:
2265 case KVM_DEV_TYPE_FSL_MPIC_42:
2266 ops = &kvm_mpic_ops;
2267 break;
2268 #endif
2269 #ifdef CONFIG_KVM_XICS
2270 case KVM_DEV_TYPE_XICS:
2271 ops = &kvm_xics_ops;
2272 break;
2273 #endif
2274 #ifdef CONFIG_KVM_VFIO
2275 case KVM_DEV_TYPE_VFIO:
2276 ops = &kvm_vfio_ops;
2277 break;
2278 #endif
2279 #ifdef CONFIG_KVM_ARM_VGIC
2280 case KVM_DEV_TYPE_ARM_VGIC_V2:
2281 ops = &kvm_arm_vgic_v2_ops;
2282 break;
2283 #endif
2284 #ifdef CONFIG_S390
2285 case KVM_DEV_TYPE_FLIC:
2286 ops = &kvm_flic_ops;
2287 break;
2288 #endif
2289 default:
2290 return -ENODEV;
2291 }
2292
2293 if (test)
2294 return 0;
2295
2296 dev = kzalloc(sizeof(*dev), GFP_KERNEL);
2297 if (!dev)
2298 return -ENOMEM;
2299
2300 dev->ops = ops;
2301 dev->kvm = kvm;
2302
2303 ret = ops->create(dev, cd->type);
2304 if (ret < 0) {
2305 kfree(dev);
2306 return ret;
2307 }
2308
2309 ret = anon_inode_getfd(ops->name, &kvm_device_fops, dev, O_RDWR | O_CLOEXEC);
2310 if (ret < 0) {
2311 ops->destroy(dev);
2312 return ret;
2313 }
2314
2315 list_add(&dev->vm_node, &kvm->devices);
2316 kvm_get_kvm(kvm);
2317 cd->fd = ret;
2318 return 0;
2319 }
2320
2321 static long kvm_vm_ioctl(struct file *filp,
2322 unsigned int ioctl, unsigned long arg)
2323 {
2324 struct kvm *kvm = filp->private_data;
2325 void __user *argp = (void __user *)arg;
2326 int r;
2327
2328 if (kvm->mm != current->mm)
2329 return -EIO;
2330 switch (ioctl) {
2331 case KVM_CREATE_VCPU:
2332 r = kvm_vm_ioctl_create_vcpu(kvm, arg);
2333 break;
2334 case KVM_SET_USER_MEMORY_REGION: {
2335 struct kvm_userspace_memory_region kvm_userspace_mem;
2336
2337 r = -EFAULT;
2338 if (copy_from_user(&kvm_userspace_mem, argp,
2339 sizeof kvm_userspace_mem))
2340 goto out;
2341
2342 r = kvm_vm_ioctl_set_memory_region(kvm, &kvm_userspace_mem);
2343 break;
2344 }
2345 case KVM_GET_DIRTY_LOG: {
2346 struct kvm_dirty_log log;
2347
2348 r = -EFAULT;
2349 if (copy_from_user(&log, argp, sizeof log))
2350 goto out;
2351 r = kvm_vm_ioctl_get_dirty_log(kvm, &log);
2352 break;
2353 }
2354 #ifdef KVM_COALESCED_MMIO_PAGE_OFFSET
2355 case KVM_REGISTER_COALESCED_MMIO: {
2356 struct kvm_coalesced_mmio_zone zone;
2357 r = -EFAULT;
2358 if (copy_from_user(&zone, argp, sizeof zone))
2359 goto out;
2360 r = kvm_vm_ioctl_register_coalesced_mmio(kvm, &zone);
2361 break;
2362 }
2363 case KVM_UNREGISTER_COALESCED_MMIO: {
2364 struct kvm_coalesced_mmio_zone zone;
2365 r = -EFAULT;
2366 if (copy_from_user(&zone, argp, sizeof zone))
2367 goto out;
2368 r = kvm_vm_ioctl_unregister_coalesced_mmio(kvm, &zone);
2369 break;
2370 }
2371 #endif
2372 case KVM_IRQFD: {
2373 struct kvm_irqfd data;
2374
2375 r = -EFAULT;
2376 if (copy_from_user(&data, argp, sizeof data))
2377 goto out;
2378 r = kvm_irqfd(kvm, &data);
2379 break;
2380 }
2381 case KVM_IOEVENTFD: {
2382 struct kvm_ioeventfd data;
2383
2384 r = -EFAULT;
2385 if (copy_from_user(&data, argp, sizeof data))
2386 goto out;
2387 r = kvm_ioeventfd(kvm, &data);
2388 break;
2389 }
2390 #ifdef CONFIG_KVM_APIC_ARCHITECTURE
2391 case KVM_SET_BOOT_CPU_ID:
2392 r = 0;
2393 mutex_lock(&kvm->lock);
2394 if (atomic_read(&kvm->online_vcpus) != 0)
2395 r = -EBUSY;
2396 else
2397 kvm->bsp_vcpu_id = arg;
2398 mutex_unlock(&kvm->lock);
2399 break;
2400 #endif
2401 #ifdef CONFIG_HAVE_KVM_MSI
2402 case KVM_SIGNAL_MSI: {
2403 struct kvm_msi msi;
2404
2405 r = -EFAULT;
2406 if (copy_from_user(&msi, argp, sizeof msi))
2407 goto out;
2408 r = kvm_send_userspace_msi(kvm, &msi);
2409 break;
2410 }
2411 #endif
2412 #ifdef __KVM_HAVE_IRQ_LINE
2413 case KVM_IRQ_LINE_STATUS:
2414 case KVM_IRQ_LINE: {
2415 struct kvm_irq_level irq_event;
2416
2417 r = -EFAULT;
2418 if (copy_from_user(&irq_event, argp, sizeof irq_event))
2419 goto out;
2420
2421 r = kvm_vm_ioctl_irq_line(kvm, &irq_event,
2422 ioctl == KVM_IRQ_LINE_STATUS);
2423 if (r)
2424 goto out;
2425
2426 r = -EFAULT;
2427 if (ioctl == KVM_IRQ_LINE_STATUS) {
2428 if (copy_to_user(argp, &irq_event, sizeof irq_event))
2429 goto out;
2430 }
2431
2432 r = 0;
2433 break;
2434 }
2435 #endif
2436 #ifdef CONFIG_HAVE_KVM_IRQ_ROUTING
2437 case KVM_SET_GSI_ROUTING: {
2438 struct kvm_irq_routing routing;
2439 struct kvm_irq_routing __user *urouting;
2440 struct kvm_irq_routing_entry *entries;
2441
2442 r = -EFAULT;
2443 if (copy_from_user(&routing, argp, sizeof(routing)))
2444 goto out;
2445 r = -EINVAL;
2446 if (routing.nr >= KVM_MAX_IRQ_ROUTES)
2447 goto out;
2448 if (routing.flags)
2449 goto out;
2450 r = -ENOMEM;
2451 entries = vmalloc(routing.nr * sizeof(*entries));
2452 if (!entries)
2453 goto out;
2454 r = -EFAULT;
2455 urouting = argp;
2456 if (copy_from_user(entries, urouting->entries,
2457 routing.nr * sizeof(*entries)))
2458 goto out_free_irq_routing;
2459 r = kvm_set_irq_routing(kvm, entries, routing.nr,
2460 routing.flags);
2461 out_free_irq_routing:
2462 vfree(entries);
2463 break;
2464 }
2465 #endif /* CONFIG_HAVE_KVM_IRQ_ROUTING */
2466 case KVM_CREATE_DEVICE: {
2467 struct kvm_create_device cd;
2468
2469 r = -EFAULT;
2470 if (copy_from_user(&cd, argp, sizeof(cd)))
2471 goto out;
2472
2473 r = kvm_ioctl_create_device(kvm, &cd);
2474 if (r)
2475 goto out;
2476
2477 r = -EFAULT;
2478 if (copy_to_user(argp, &cd, sizeof(cd)))
2479 goto out;
2480
2481 r = 0;
2482 break;
2483 }
2484 default:
2485 r = kvm_arch_vm_ioctl(filp, ioctl, arg);
2486 if (r == -ENOTTY)
2487 r = kvm_vm_ioctl_assigned_device(kvm, ioctl, arg);
2488 }
2489 out:
2490 return r;
2491 }
2492
2493 #ifdef CONFIG_COMPAT
2494 struct compat_kvm_dirty_log {
2495 __u32 slot;
2496 __u32 padding1;
2497 union {
2498 compat_uptr_t dirty_bitmap; /* one bit per page */
2499 __u64 padding2;
2500 };
2501 };
2502
2503 static long kvm_vm_compat_ioctl(struct file *filp,
2504 unsigned int ioctl, unsigned long arg)
2505 {
2506 struct kvm *kvm = filp->private_data;
2507 int r;
2508
2509 if (kvm->mm != current->mm)
2510 return -EIO;
2511 switch (ioctl) {
2512 case KVM_GET_DIRTY_LOG: {
2513 struct compat_kvm_dirty_log compat_log;
2514 struct kvm_dirty_log log;
2515
2516 r = -EFAULT;
2517 if (copy_from_user(&compat_log, (void __user *)arg,
2518 sizeof(compat_log)))
2519 goto out;
2520 log.slot = compat_log.slot;
2521 log.padding1 = compat_log.padding1;
2522 log.padding2 = compat_log.padding2;
2523 log.dirty_bitmap = compat_ptr(compat_log.dirty_bitmap);
2524
2525 r = kvm_vm_ioctl_get_dirty_log(kvm, &log);
2526 break;
2527 }
2528 default:
2529 r = kvm_vm_ioctl(filp, ioctl, arg);
2530 }
2531
2532 out:
2533 return r;
2534 }
2535 #endif
2536
2537 static struct file_operations kvm_vm_fops = {
2538 .release = kvm_vm_release,
2539 .unlocked_ioctl = kvm_vm_ioctl,
2540 #ifdef CONFIG_COMPAT
2541 .compat_ioctl = kvm_vm_compat_ioctl,
2542 #endif
2543 .llseek = noop_llseek,
2544 };
2545
2546 static int kvm_dev_ioctl_create_vm(unsigned long type)
2547 {
2548 int r;
2549 struct kvm *kvm;
2550
2551 kvm = kvm_create_vm(type);
2552 if (IS_ERR(kvm))
2553 return PTR_ERR(kvm);
2554 #ifdef KVM_COALESCED_MMIO_PAGE_OFFSET
2555 r = kvm_coalesced_mmio_init(kvm);
2556 if (r < 0) {
2557 kvm_put_kvm(kvm);
2558 return r;
2559 }
2560 #endif
2561 r = anon_inode_getfd("kvm-vm", &kvm_vm_fops, kvm, O_RDWR | O_CLOEXEC);
2562 if (r < 0)
2563 kvm_put_kvm(kvm);
2564
2565 return r;
2566 }
2567
2568 static long kvm_dev_ioctl_check_extension_generic(long arg)
2569 {
2570 switch (arg) {
2571 case KVM_CAP_USER_MEMORY:
2572 case KVM_CAP_DESTROY_MEMORY_REGION_WORKS:
2573 case KVM_CAP_JOIN_MEMORY_REGIONS_WORKS:
2574 #ifdef CONFIG_KVM_APIC_ARCHITECTURE
2575 case KVM_CAP_SET_BOOT_CPU_ID:
2576 #endif
2577 case KVM_CAP_INTERNAL_ERROR_DATA:
2578 #ifdef CONFIG_HAVE_KVM_MSI
2579 case KVM_CAP_SIGNAL_MSI:
2580 #endif
2581 #ifdef CONFIG_HAVE_KVM_IRQ_ROUTING
2582 case KVM_CAP_IRQFD_RESAMPLE:
2583 #endif
2584 return 1;
2585 #ifdef CONFIG_HAVE_KVM_IRQ_ROUTING
2586 case KVM_CAP_IRQ_ROUTING:
2587 return KVM_MAX_IRQ_ROUTES;
2588 #endif
2589 default:
2590 break;
2591 }
2592 return kvm_dev_ioctl_check_extension(arg);
2593 }
2594
2595 static long kvm_dev_ioctl(struct file *filp,
2596 unsigned int ioctl, unsigned long arg)
2597 {
2598 long r = -EINVAL;
2599
2600 switch (ioctl) {
2601 case KVM_GET_API_VERSION:
2602 r = -EINVAL;
2603 if (arg)
2604 goto out;
2605 r = KVM_API_VERSION;
2606 break;
2607 case KVM_CREATE_VM:
2608 r = kvm_dev_ioctl_create_vm(arg);
2609 break;
2610 case KVM_CHECK_EXTENSION:
2611 r = kvm_dev_ioctl_check_extension_generic(arg);
2612 break;
2613 case KVM_GET_VCPU_MMAP_SIZE:
2614 r = -EINVAL;
2615 if (arg)
2616 goto out;
2617 r = PAGE_SIZE; /* struct kvm_run */
2618 #ifdef CONFIG_X86
2619 r += PAGE_SIZE; /* pio data page */
2620 #endif
2621 #ifdef KVM_COALESCED_MMIO_PAGE_OFFSET
2622 r += PAGE_SIZE; /* coalesced mmio ring page */
2623 #endif
2624 break;
2625 case KVM_TRACE_ENABLE:
2626 case KVM_TRACE_PAUSE:
2627 case KVM_TRACE_DISABLE:
2628 r = -EOPNOTSUPP;
2629 break;
2630 default:
2631 return kvm_arch_dev_ioctl(filp, ioctl, arg);
2632 }
2633 out:
2634 return r;
2635 }
2636
2637 static struct file_operations kvm_chardev_ops = {
2638 .unlocked_ioctl = kvm_dev_ioctl,
2639 .compat_ioctl = kvm_dev_ioctl,
2640 .llseek = noop_llseek,
2641 };
2642
2643 static struct miscdevice kvm_dev = {
2644 KVM_MINOR,
2645 "kvm",
2646 &kvm_chardev_ops,
2647 };
2648
2649 static void hardware_enable_nolock(void *junk)
2650 {
2651 int cpu = raw_smp_processor_id();
2652 int r;
2653
2654 if (cpumask_test_cpu(cpu, cpus_hardware_enabled))
2655 return;
2656
2657 cpumask_set_cpu(cpu, cpus_hardware_enabled);
2658
2659 r = kvm_arch_hardware_enable(NULL);
2660
2661 if (r) {
2662 cpumask_clear_cpu(cpu, cpus_hardware_enabled);
2663 atomic_inc(&hardware_enable_failed);
2664 printk(KERN_INFO "kvm: enabling virtualization on "
2665 "CPU%d failed\n", cpu);
2666 }
2667 }
2668
2669 static void hardware_enable(void)
2670 {
2671 raw_spin_lock(&kvm_count_lock);
2672 if (kvm_usage_count)
2673 hardware_enable_nolock(NULL);
2674 raw_spin_unlock(&kvm_count_lock);
2675 }
2676
2677 static void hardware_disable_nolock(void *junk)
2678 {
2679 int cpu = raw_smp_processor_id();
2680
2681 if (!cpumask_test_cpu(cpu, cpus_hardware_enabled))
2682 return;
2683 cpumask_clear_cpu(cpu, cpus_hardware_enabled);
2684 kvm_arch_hardware_disable(NULL);
2685 }
2686
2687 static void hardware_disable(void)
2688 {
2689 raw_spin_lock(&kvm_count_lock);
2690 if (kvm_usage_count)
2691 hardware_disable_nolock(NULL);
2692 raw_spin_unlock(&kvm_count_lock);
2693 }
2694
2695 static void hardware_disable_all_nolock(void)
2696 {
2697 BUG_ON(!kvm_usage_count);
2698
2699 kvm_usage_count--;
2700 if (!kvm_usage_count)
2701 on_each_cpu(hardware_disable_nolock, NULL, 1);
2702 }
2703
2704 static void hardware_disable_all(void)
2705 {
2706 raw_spin_lock(&kvm_count_lock);
2707 hardware_disable_all_nolock();
2708 raw_spin_unlock(&kvm_count_lock);
2709 }
2710
2711 static int hardware_enable_all(void)
2712 {
2713 int r = 0;
2714
2715 raw_spin_lock(&kvm_count_lock);
2716
2717 kvm_usage_count++;
2718 if (kvm_usage_count == 1) {
2719 atomic_set(&hardware_enable_failed, 0);
2720 on_each_cpu(hardware_enable_nolock, NULL, 1);
2721
2722 if (atomic_read(&hardware_enable_failed)) {
2723 hardware_disable_all_nolock();
2724 r = -EBUSY;
2725 }
2726 }
2727
2728 raw_spin_unlock(&kvm_count_lock);
2729
2730 return r;
2731 }
2732
2733 static int kvm_cpu_hotplug(struct notifier_block *notifier, unsigned long val,
2734 void *v)
2735 {
2736 int cpu = (long)v;
2737
2738 val &= ~CPU_TASKS_FROZEN;
2739 switch (val) {
2740 case CPU_DYING:
2741 printk(KERN_INFO "kvm: disabling virtualization on CPU%d\n",
2742 cpu);
2743 hardware_disable();
2744 break;
2745 case CPU_STARTING:
2746 printk(KERN_INFO "kvm: enabling virtualization on CPU%d\n",
2747 cpu);
2748 hardware_enable();
2749 break;
2750 }
2751 return NOTIFY_OK;
2752 }
2753
2754 static int kvm_reboot(struct notifier_block *notifier, unsigned long val,
2755 void *v)
2756 {
2757 /*
2758 * Some (well, at least mine) BIOSes hang on reboot if
2759 * in vmx root mode.
2760 *
2761 * And Intel TXT required VMX off for all cpu when system shutdown.
2762 */
2763 printk(KERN_INFO "kvm: exiting hardware virtualization\n");
2764 kvm_rebooting = true;
2765 on_each_cpu(hardware_disable_nolock, NULL, 1);
2766 return NOTIFY_OK;
2767 }
2768
2769 static struct notifier_block kvm_reboot_notifier = {
2770 .notifier_call = kvm_reboot,
2771 .priority = 0,
2772 };
2773
2774 static void kvm_io_bus_destroy(struct kvm_io_bus *bus)
2775 {
2776 int i;
2777
2778 for (i = 0; i < bus->dev_count; i++) {
2779 struct kvm_io_device *pos = bus->range[i].dev;
2780
2781 kvm_iodevice_destructor(pos);
2782 }
2783 kfree(bus);
2784 }
2785
2786 static inline int kvm_io_bus_cmp(const struct kvm_io_range *r1,
2787 const struct kvm_io_range *r2)
2788 {
2789 if (r1->addr < r2->addr)
2790 return -1;
2791 if (r1->addr + r1->len > r2->addr + r2->len)
2792 return 1;
2793 return 0;
2794 }
2795
2796 static int kvm_io_bus_sort_cmp(const void *p1, const void *p2)
2797 {
2798 return kvm_io_bus_cmp(p1, p2);
2799 }
2800
2801 static int kvm_io_bus_insert_dev(struct kvm_io_bus *bus, struct kvm_io_device *dev,
2802 gpa_t addr, int len)
2803 {
2804 bus->range[bus->dev_count++] = (struct kvm_io_range) {
2805 .addr = addr,
2806 .len = len,
2807 .dev = dev,
2808 };
2809
2810 sort(bus->range, bus->dev_count, sizeof(struct kvm_io_range),
2811 kvm_io_bus_sort_cmp, NULL);
2812
2813 return 0;
2814 }
2815
2816 static int kvm_io_bus_get_first_dev(struct kvm_io_bus *bus,
2817 gpa_t addr, int len)
2818 {
2819 struct kvm_io_range *range, key;
2820 int off;
2821
2822 key = (struct kvm_io_range) {
2823 .addr = addr,
2824 .len = len,
2825 };
2826
2827 range = bsearch(&key, bus->range, bus->dev_count,
2828 sizeof(struct kvm_io_range), kvm_io_bus_sort_cmp);
2829 if (range == NULL)
2830 return -ENOENT;
2831
2832 off = range - bus->range;
2833
2834 while (off > 0 && kvm_io_bus_cmp(&key, &bus->range[off-1]) == 0)
2835 off--;
2836
2837 return off;
2838 }
2839
2840 static int __kvm_io_bus_write(struct kvm_io_bus *bus,
2841 struct kvm_io_range *range, const void *val)
2842 {
2843 int idx;
2844
2845 idx = kvm_io_bus_get_first_dev(bus, range->addr, range->len);
2846 if (idx < 0)
2847 return -EOPNOTSUPP;
2848
2849 while (idx < bus->dev_count &&
2850 kvm_io_bus_cmp(range, &bus->range[idx]) == 0) {
2851 if (!kvm_iodevice_write(bus->range[idx].dev, range->addr,
2852 range->len, val))
2853 return idx;
2854 idx++;
2855 }
2856
2857 return -EOPNOTSUPP;
2858 }
2859
2860 /* kvm_io_bus_write - called under kvm->slots_lock */
2861 int kvm_io_bus_write(struct kvm *kvm, enum kvm_bus bus_idx, gpa_t addr,
2862 int len, const void *val)
2863 {
2864 struct kvm_io_bus *bus;
2865 struct kvm_io_range range;
2866 int r;
2867
2868 range = (struct kvm_io_range) {
2869 .addr = addr,
2870 .len = len,
2871 };
2872
2873 bus = srcu_dereference(kvm->buses[bus_idx], &kvm->srcu);
2874 r = __kvm_io_bus_write(bus, &range, val);
2875 return r < 0 ? r : 0;
2876 }
2877
2878 /* kvm_io_bus_write_cookie - called under kvm->slots_lock */
2879 int kvm_io_bus_write_cookie(struct kvm *kvm, enum kvm_bus bus_idx, gpa_t addr,
2880 int len, const void *val, long cookie)
2881 {
2882 struct kvm_io_bus *bus;
2883 struct kvm_io_range range;
2884
2885 range = (struct kvm_io_range) {
2886 .addr = addr,
2887 .len = len,
2888 };
2889
2890 bus = srcu_dereference(kvm->buses[bus_idx], &kvm->srcu);
2891
2892 /* First try the device referenced by cookie. */
2893 if ((cookie >= 0) && (cookie < bus->dev_count) &&
2894 (kvm_io_bus_cmp(&range, &bus->range[cookie]) == 0))
2895 if (!kvm_iodevice_write(bus->range[cookie].dev, addr, len,
2896 val))
2897 return cookie;
2898
2899 /*
2900 * cookie contained garbage; fall back to search and return the
2901 * correct cookie value.
2902 */
2903 return __kvm_io_bus_write(bus, &range, val);
2904 }
2905
2906 static int __kvm_io_bus_read(struct kvm_io_bus *bus, struct kvm_io_range *range,
2907 void *val)
2908 {
2909 int idx;
2910
2911 idx = kvm_io_bus_get_first_dev(bus, range->addr, range->len);
2912 if (idx < 0)
2913 return -EOPNOTSUPP;
2914
2915 while (idx < bus->dev_count &&
2916 kvm_io_bus_cmp(range, &bus->range[idx]) == 0) {
2917 if (!kvm_iodevice_read(bus->range[idx].dev, range->addr,
2918 range->len, val))
2919 return idx;
2920 idx++;
2921 }
2922
2923 return -EOPNOTSUPP;
2924 }
2925
2926 /* kvm_io_bus_read - called under kvm->slots_lock */
2927 int kvm_io_bus_read(struct kvm *kvm, enum kvm_bus bus_idx, gpa_t addr,
2928 int len, void *val)
2929 {
2930 struct kvm_io_bus *bus;
2931 struct kvm_io_range range;
2932 int r;
2933
2934 range = (struct kvm_io_range) {
2935 .addr = addr,
2936 .len = len,
2937 };
2938
2939 bus = srcu_dereference(kvm->buses[bus_idx], &kvm->srcu);
2940 r = __kvm_io_bus_read(bus, &range, val);
2941 return r < 0 ? r : 0;
2942 }
2943
2944
2945 /* Caller must hold slots_lock. */
2946 int kvm_io_bus_register_dev(struct kvm *kvm, enum kvm_bus bus_idx, gpa_t addr,
2947 int len, struct kvm_io_device *dev)
2948 {
2949 struct kvm_io_bus *new_bus, *bus;
2950
2951 bus = kvm->buses[bus_idx];
2952 /* exclude ioeventfd which is limited by maximum fd */
2953 if (bus->dev_count - bus->ioeventfd_count > NR_IOBUS_DEVS - 1)
2954 return -ENOSPC;
2955
2956 new_bus = kzalloc(sizeof(*bus) + ((bus->dev_count + 1) *
2957 sizeof(struct kvm_io_range)), GFP_KERNEL);
2958 if (!new_bus)
2959 return -ENOMEM;
2960 memcpy(new_bus, bus, sizeof(*bus) + (bus->dev_count *
2961 sizeof(struct kvm_io_range)));
2962 kvm_io_bus_insert_dev(new_bus, dev, addr, len);
2963 rcu_assign_pointer(kvm->buses[bus_idx], new_bus);
2964 synchronize_srcu_expedited(&kvm->srcu);
2965 kfree(bus);
2966
2967 return 0;
2968 }
2969
2970 /* Caller must hold slots_lock. */
2971 int kvm_io_bus_unregister_dev(struct kvm *kvm, enum kvm_bus bus_idx,
2972 struct kvm_io_device *dev)
2973 {
2974 int i, r;
2975 struct kvm_io_bus *new_bus, *bus;
2976
2977 bus = kvm->buses[bus_idx];
2978 r = -ENOENT;
2979 for (i = 0; i < bus->dev_count; i++)
2980 if (bus->range[i].dev == dev) {
2981 r = 0;
2982 break;
2983 }
2984
2985 if (r)
2986 return r;
2987
2988 new_bus = kzalloc(sizeof(*bus) + ((bus->dev_count - 1) *
2989 sizeof(struct kvm_io_range)), GFP_KERNEL);
2990 if (!new_bus)
2991 return -ENOMEM;
2992
2993 memcpy(new_bus, bus, sizeof(*bus) + i * sizeof(struct kvm_io_range));
2994 new_bus->dev_count--;
2995 memcpy(new_bus->range + i, bus->range + i + 1,
2996 (new_bus->dev_count - i) * sizeof(struct kvm_io_range));
2997
2998 rcu_assign_pointer(kvm->buses[bus_idx], new_bus);
2999 synchronize_srcu_expedited(&kvm->srcu);
3000 kfree(bus);
3001 return r;
3002 }
3003
3004 static struct notifier_block kvm_cpu_notifier = {
3005 .notifier_call = kvm_cpu_hotplug,
3006 };
3007
3008 static int vm_stat_get(void *_offset, u64 *val)
3009 {
3010 unsigned offset = (long)_offset;
3011 struct kvm *kvm;
3012
3013 *val = 0;
3014 spin_lock(&kvm_lock);
3015 list_for_each_entry(kvm, &vm_list, vm_list)
3016 *val += *(u32 *)((void *)kvm + offset);
3017 spin_unlock(&kvm_lock);
3018 return 0;
3019 }
3020
3021 DEFINE_SIMPLE_ATTRIBUTE(vm_stat_fops, vm_stat_get, NULL, "%llu\n");
3022
3023 static int vcpu_stat_get(void *_offset, u64 *val)
3024 {
3025 unsigned offset = (long)_offset;
3026 struct kvm *kvm;
3027 struct kvm_vcpu *vcpu;
3028 int i;
3029
3030 *val = 0;
3031 spin_lock(&kvm_lock);
3032 list_for_each_entry(kvm, &vm_list, vm_list)
3033 kvm_for_each_vcpu(i, vcpu, kvm)
3034 *val += *(u32 *)((void *)vcpu + offset);
3035
3036 spin_unlock(&kvm_lock);
3037 return 0;
3038 }
3039
3040 DEFINE_SIMPLE_ATTRIBUTE(vcpu_stat_fops, vcpu_stat_get, NULL, "%llu\n");
3041
3042 static const struct file_operations *stat_fops[] = {
3043 [KVM_STAT_VCPU] = &vcpu_stat_fops,
3044 [KVM_STAT_VM] = &vm_stat_fops,
3045 };
3046
3047 static int kvm_init_debug(void)
3048 {
3049 int r = -EEXIST;
3050 struct kvm_stats_debugfs_item *p;
3051
3052 kvm_debugfs_dir = debugfs_create_dir("kvm", NULL);
3053 if (kvm_debugfs_dir == NULL)
3054 goto out;
3055
3056 for (p = debugfs_entries; p->name; ++p) {
3057 p->dentry = debugfs_create_file(p->name, 0444, kvm_debugfs_dir,
3058 (void *)(long)p->offset,
3059 stat_fops[p->kind]);
3060 if (p->dentry == NULL)
3061 goto out_dir;
3062 }
3063
3064 return 0;
3065
3066 out_dir:
3067 debugfs_remove_recursive(kvm_debugfs_dir);
3068 out:
3069 return r;
3070 }
3071
3072 static void kvm_exit_debug(void)
3073 {
3074 struct kvm_stats_debugfs_item *p;
3075
3076 for (p = debugfs_entries; p->name; ++p)
3077 debugfs_remove(p->dentry);
3078 debugfs_remove(kvm_debugfs_dir);
3079 }
3080
3081 static int kvm_suspend(void)
3082 {
3083 if (kvm_usage_count)
3084 hardware_disable_nolock(NULL);
3085 return 0;
3086 }
3087
3088 static void kvm_resume(void)
3089 {
3090 if (kvm_usage_count) {
3091 WARN_ON(raw_spin_is_locked(&kvm_count_lock));
3092 hardware_enable_nolock(NULL);
3093 }
3094 }
3095
3096 static struct syscore_ops kvm_syscore_ops = {
3097 .suspend = kvm_suspend,
3098 .resume = kvm_resume,
3099 };
3100
3101 static inline
3102 struct kvm_vcpu *preempt_notifier_to_vcpu(struct preempt_notifier *pn)
3103 {
3104 return container_of(pn, struct kvm_vcpu, preempt_notifier);
3105 }
3106
3107 static void kvm_sched_in(struct preempt_notifier *pn, int cpu)
3108 {
3109 struct kvm_vcpu *vcpu = preempt_notifier_to_vcpu(pn);
3110 if (vcpu->preempted)
3111 vcpu->preempted = false;
3112
3113 kvm_arch_vcpu_load(vcpu, cpu);
3114 }
3115
3116 static void kvm_sched_out(struct preempt_notifier *pn,
3117 struct task_struct *next)
3118 {
3119 struct kvm_vcpu *vcpu = preempt_notifier_to_vcpu(pn);
3120
3121 if (current->state == TASK_RUNNING)
3122 vcpu->preempted = true;
3123 kvm_arch_vcpu_put(vcpu);
3124 }
3125
3126 int kvm_init(void *opaque, unsigned vcpu_size, unsigned vcpu_align,
3127 struct module *module)
3128 {
3129 int r;
3130 int cpu;
3131
3132 r = kvm_arch_init(opaque);
3133 if (r)
3134 goto out_fail;
3135
3136 /*
3137 * kvm_arch_init makes sure there's at most one caller
3138 * for architectures that support multiple implementations,
3139 * like intel and amd on x86.
3140 * kvm_arch_init must be called before kvm_irqfd_init to avoid creating
3141 * conflicts in case kvm is already setup for another implementation.
3142 */
3143 r = kvm_irqfd_init();
3144 if (r)
3145 goto out_irqfd;
3146
3147 if (!zalloc_cpumask_var(&cpus_hardware_enabled, GFP_KERNEL)) {
3148 r = -ENOMEM;
3149 goto out_free_0;
3150 }
3151
3152 r = kvm_arch_hardware_setup();
3153 if (r < 0)
3154 goto out_free_0a;
3155
3156 for_each_online_cpu(cpu) {
3157 smp_call_function_single(cpu,
3158 kvm_arch_check_processor_compat,
3159 &r, 1);
3160 if (r < 0)
3161 goto out_free_1;
3162 }
3163
3164 r = register_cpu_notifier(&kvm_cpu_notifier);
3165 if (r)
3166 goto out_free_2;
3167 register_reboot_notifier(&kvm_reboot_notifier);
3168
3169 /* A kmem cache lets us meet the alignment requirements of fx_save. */
3170 if (!vcpu_align)
3171 vcpu_align = __alignof__(struct kvm_vcpu);
3172 kvm_vcpu_cache = kmem_cache_create("kvm_vcpu", vcpu_size, vcpu_align,
3173 0, NULL);
3174 if (!kvm_vcpu_cache) {
3175 r = -ENOMEM;
3176 goto out_free_3;
3177 }
3178
3179 r = kvm_async_pf_init();
3180 if (r)
3181 goto out_free;
3182
3183 kvm_chardev_ops.owner = module;
3184 kvm_vm_fops.owner = module;
3185 kvm_vcpu_fops.owner = module;
3186
3187 r = misc_register(&kvm_dev);
3188 if (r) {
3189 printk(KERN_ERR "kvm: misc device register failed\n");
3190 goto out_unreg;
3191 }
3192
3193 register_syscore_ops(&kvm_syscore_ops);
3194
3195 kvm_preempt_ops.sched_in = kvm_sched_in;
3196 kvm_preempt_ops.sched_out = kvm_sched_out;
3197
3198 r = kvm_init_debug();
3199 if (r) {
3200 printk(KERN_ERR "kvm: create debugfs files failed\n");
3201 goto out_undebugfs;
3202 }
3203
3204 return 0;
3205
3206 out_undebugfs:
3207 unregister_syscore_ops(&kvm_syscore_ops);
3208 misc_deregister(&kvm_dev);
3209 out_unreg:
3210 kvm_async_pf_deinit();
3211 out_free:
3212 kmem_cache_destroy(kvm_vcpu_cache);
3213 out_free_3:
3214 unregister_reboot_notifier(&kvm_reboot_notifier);
3215 unregister_cpu_notifier(&kvm_cpu_notifier);
3216 out_free_2:
3217 out_free_1:
3218 kvm_arch_hardware_unsetup();
3219 out_free_0a:
3220 free_cpumask_var(cpus_hardware_enabled);
3221 out_free_0:
3222 kvm_irqfd_exit();
3223 out_irqfd:
3224 kvm_arch_exit();
3225 out_fail:
3226 return r;
3227 }
3228 EXPORT_SYMBOL_GPL(kvm_init);
3229
3230 void kvm_exit(void)
3231 {
3232 kvm_exit_debug();
3233 misc_deregister(&kvm_dev);
3234 kmem_cache_destroy(kvm_vcpu_cache);
3235 kvm_async_pf_deinit();
3236 unregister_syscore_ops(&kvm_syscore_ops);
3237 unregister_reboot_notifier(&kvm_reboot_notifier);
3238 unregister_cpu_notifier(&kvm_cpu_notifier);
3239 on_each_cpu(hardware_disable_nolock, NULL, 1);
3240 kvm_arch_hardware_unsetup();
3241 kvm_arch_exit();
3242 kvm_irqfd_exit();
3243 free_cpumask_var(cpus_hardware_enabled);
3244 }
3245 EXPORT_SYMBOL_GPL(kvm_exit);
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