1 // SPDX-License-Identifier: GPL-2.0-only
3 * Kernel-based Virtual Machine driver for Linux
5 * This module enables machines with Intel VT-x extensions to run virtual
6 * machines without emulation or binary translation.
8 * Copyright (C) 2006 Qumranet, Inc.
9 * Copyright 2010 Red Hat, Inc. and/or its affiliates.
12 * Avi Kivity <avi@qumranet.com>
13 * Yaniv Kamay <yaniv@qumranet.com>
16 #include <kvm/iodev.h>
18 #include <linux/kvm_host.h>
19 #include <linux/kvm.h>
20 #include <linux/module.h>
21 #include <linux/errno.h>
22 #include <linux/percpu.h>
24 #include <linux/miscdevice.h>
25 #include <linux/vmalloc.h>
26 #include <linux/reboot.h>
27 #include <linux/debugfs.h>
28 #include <linux/highmem.h>
29 #include <linux/file.h>
30 #include <linux/syscore_ops.h>
31 #include <linux/cpu.h>
32 #include <linux/sched/signal.h>
33 #include <linux/sched/mm.h>
34 #include <linux/sched/stat.h>
35 #include <linux/cpumask.h>
36 #include <linux/smp.h>
37 #include <linux/anon_inodes.h>
38 #include <linux/profile.h>
39 #include <linux/kvm_para.h>
40 #include <linux/pagemap.h>
41 #include <linux/mman.h>
42 #include <linux/swap.h>
43 #include <linux/bitops.h>
44 #include <linux/spinlock.h>
45 #include <linux/compat.h>
46 #include <linux/srcu.h>
47 #include <linux/hugetlb.h>
48 #include <linux/slab.h>
49 #include <linux/sort.h>
50 #include <linux/bsearch.h>
52 #include <linux/lockdep.h>
53 #include <linux/kthread.h>
55 #include <asm/processor.h>
56 #include <asm/ioctl.h>
57 #include <linux/uaccess.h>
58 #include <asm/pgtable.h>
60 #include "coalesced_mmio.h"
64 #define CREATE_TRACE_POINTS
65 #include <trace/events/kvm.h>
67 /* Worst case buffer size needed for holding an integer. */
68 #define ITOA_MAX_LEN 12
70 MODULE_AUTHOR("Qumranet");
71 MODULE_LICENSE("GPL");
73 /* Architectures should define their poll value according to the halt latency */
74 unsigned int halt_poll_ns = KVM_HALT_POLL_NS_DEFAULT;
75 module_param(halt_poll_ns, uint, 0644);
76 EXPORT_SYMBOL_GPL(halt_poll_ns);
78 /* Default doubles per-vcpu halt_poll_ns. */
79 unsigned int halt_poll_ns_grow = 2;
80 module_param(halt_poll_ns_grow, uint, 0644);
81 EXPORT_SYMBOL_GPL(halt_poll_ns_grow);
83 /* The start value to grow halt_poll_ns from */
84 unsigned int halt_poll_ns_grow_start = 10000; /* 10us */
85 module_param(halt_poll_ns_grow_start, uint, 0644);
86 EXPORT_SYMBOL_GPL(halt_poll_ns_grow_start);
88 /* Default resets per-vcpu halt_poll_ns . */
89 unsigned int halt_poll_ns_shrink;
90 module_param(halt_poll_ns_shrink, uint, 0644);
91 EXPORT_SYMBOL_GPL(halt_poll_ns_shrink);
96 * kvm->lock --> kvm->slots_lock --> kvm->irq_lock
99 DEFINE_MUTEX(kvm_lock);
100 static DEFINE_RAW_SPINLOCK(kvm_count_lock);
103 static cpumask_var_t cpus_hardware_enabled;
104 static int kvm_usage_count;
105 static atomic_t hardware_enable_failed;
107 static struct kmem_cache *kvm_vcpu_cache;
109 static __read_mostly struct preempt_ops kvm_preempt_ops;
110 static DEFINE_PER_CPU(struct kvm_vcpu *, kvm_running_vcpu);
112 struct dentry *kvm_debugfs_dir;
113 EXPORT_SYMBOL_GPL(kvm_debugfs_dir);
115 static int kvm_debugfs_num_entries;
116 static const struct file_operations stat_fops_per_vm;
118 static long kvm_vcpu_ioctl(struct file *file, unsigned int ioctl,
120 #ifdef CONFIG_KVM_COMPAT
121 static long kvm_vcpu_compat_ioctl(struct file *file, unsigned int ioctl,
123 #define KVM_COMPAT(c) .compat_ioctl = (c)
126 * For architectures that don't implement a compat infrastructure,
127 * adopt a double line of defense:
128 * - Prevent a compat task from opening /dev/kvm
129 * - If the open has been done by a 64bit task, and the KVM fd
130 * passed to a compat task, let the ioctls fail.
132 static long kvm_no_compat_ioctl(struct file *file, unsigned int ioctl,
133 unsigned long arg) { return -EINVAL; }
135 static int kvm_no_compat_open(struct inode *inode, struct file *file)
137 return is_compat_task() ? -ENODEV : 0;
139 #define KVM_COMPAT(c) .compat_ioctl = kvm_no_compat_ioctl, \
140 .open = kvm_no_compat_open
142 static int hardware_enable_all(void);
143 static void hardware_disable_all(void);
145 static void kvm_io_bus_destroy(struct kvm_io_bus *bus);
147 static void mark_page_dirty_in_slot(struct kvm_memory_slot *memslot, gfn_t gfn);
149 __visible bool kvm_rebooting;
150 EXPORT_SYMBOL_GPL(kvm_rebooting);
152 #define KVM_EVENT_CREATE_VM 0
153 #define KVM_EVENT_DESTROY_VM 1
154 static void kvm_uevent_notify_change(unsigned int type, struct kvm *kvm);
155 static unsigned long long kvm_createvm_count;
156 static unsigned long long kvm_active_vms;
158 __weak int kvm_arch_mmu_notifier_invalidate_range(struct kvm *kvm,
159 unsigned long start, unsigned long end, bool blockable)
164 bool kvm_is_zone_device_pfn(kvm_pfn_t pfn)
167 * The metadata used by is_zone_device_page() to determine whether or
168 * not a page is ZONE_DEVICE is guaranteed to be valid if and only if
169 * the device has been pinned, e.g. by get_user_pages(). WARN if the
170 * page_count() is zero to help detect bad usage of this helper.
172 if (!pfn_valid(pfn) || WARN_ON_ONCE(!page_count(pfn_to_page(pfn))))
175 return is_zone_device_page(pfn_to_page(pfn));
178 bool kvm_is_reserved_pfn(kvm_pfn_t pfn)
181 * ZONE_DEVICE pages currently set PG_reserved, but from a refcounting
182 * perspective they are "normal" pages, albeit with slightly different
186 return PageReserved(pfn_to_page(pfn)) &&
188 !kvm_is_zone_device_pfn(pfn);
193 bool kvm_is_transparent_hugepage(kvm_pfn_t pfn)
195 struct page *page = pfn_to_page(pfn);
197 if (!PageTransCompoundMap(page))
200 return is_transparent_hugepage(compound_head(page));
204 * Switches to specified vcpu, until a matching vcpu_put()
206 void vcpu_load(struct kvm_vcpu *vcpu)
210 __this_cpu_write(kvm_running_vcpu, vcpu);
211 preempt_notifier_register(&vcpu->preempt_notifier);
212 kvm_arch_vcpu_load(vcpu, cpu);
215 EXPORT_SYMBOL_GPL(vcpu_load);
217 void vcpu_put(struct kvm_vcpu *vcpu)
220 kvm_arch_vcpu_put(vcpu);
221 preempt_notifier_unregister(&vcpu->preempt_notifier);
222 __this_cpu_write(kvm_running_vcpu, NULL);
225 EXPORT_SYMBOL_GPL(vcpu_put);
227 /* TODO: merge with kvm_arch_vcpu_should_kick */
228 static bool kvm_request_needs_ipi(struct kvm_vcpu *vcpu, unsigned req)
230 int mode = kvm_vcpu_exiting_guest_mode(vcpu);
233 * We need to wait for the VCPU to reenable interrupts and get out of
234 * READING_SHADOW_PAGE_TABLES mode.
236 if (req & KVM_REQUEST_WAIT)
237 return mode != OUTSIDE_GUEST_MODE;
240 * Need to kick a running VCPU, but otherwise there is nothing to do.
242 return mode == IN_GUEST_MODE;
245 static void ack_flush(void *_completed)
249 static inline bool kvm_kick_many_cpus(const struct cpumask *cpus, bool wait)
252 cpus = cpu_online_mask;
254 if (cpumask_empty(cpus))
257 smp_call_function_many(cpus, ack_flush, NULL, wait);
261 bool kvm_make_vcpus_request_mask(struct kvm *kvm, unsigned int req,
262 struct kvm_vcpu *except,
263 unsigned long *vcpu_bitmap, cpumask_var_t tmp)
266 struct kvm_vcpu *vcpu;
271 kvm_for_each_vcpu(i, vcpu, kvm) {
272 if ((vcpu_bitmap && !test_bit(i, vcpu_bitmap)) ||
276 kvm_make_request(req, vcpu);
279 if (!(req & KVM_REQUEST_NO_WAKEUP) && kvm_vcpu_wake_up(vcpu))
282 if (tmp != NULL && cpu != -1 && cpu != me &&
283 kvm_request_needs_ipi(vcpu, req))
284 __cpumask_set_cpu(cpu, tmp);
287 called = kvm_kick_many_cpus(tmp, !!(req & KVM_REQUEST_WAIT));
293 bool kvm_make_all_cpus_request_except(struct kvm *kvm, unsigned int req,
294 struct kvm_vcpu *except)
299 zalloc_cpumask_var(&cpus, GFP_ATOMIC);
301 called = kvm_make_vcpus_request_mask(kvm, req, except, NULL, cpus);
303 free_cpumask_var(cpus);
307 bool kvm_make_all_cpus_request(struct kvm *kvm, unsigned int req)
309 return kvm_make_all_cpus_request_except(kvm, req, NULL);
312 #ifndef CONFIG_HAVE_KVM_ARCH_TLB_FLUSH_ALL
313 void kvm_flush_remote_tlbs(struct kvm *kvm)
316 * Read tlbs_dirty before setting KVM_REQ_TLB_FLUSH in
317 * kvm_make_all_cpus_request.
319 long dirty_count = smp_load_acquire(&kvm->tlbs_dirty);
322 * We want to publish modifications to the page tables before reading
323 * mode. Pairs with a memory barrier in arch-specific code.
324 * - x86: smp_mb__after_srcu_read_unlock in vcpu_enter_guest
325 * and smp_mb in walk_shadow_page_lockless_begin/end.
326 * - powerpc: smp_mb in kvmppc_prepare_to_enter.
328 * There is already an smp_mb__after_atomic() before
329 * kvm_make_all_cpus_request() reads vcpu->mode. We reuse that
332 if (!kvm_arch_flush_remote_tlb(kvm)
333 || kvm_make_all_cpus_request(kvm, KVM_REQ_TLB_FLUSH))
334 ++kvm->stat.remote_tlb_flush;
335 cmpxchg(&kvm->tlbs_dirty, dirty_count, 0);
337 EXPORT_SYMBOL_GPL(kvm_flush_remote_tlbs);
340 void kvm_reload_remote_mmus(struct kvm *kvm)
342 kvm_make_all_cpus_request(kvm, KVM_REQ_MMU_RELOAD);
345 static void kvm_vcpu_init(struct kvm_vcpu *vcpu, struct kvm *kvm, unsigned id)
347 mutex_init(&vcpu->mutex);
352 rcuwait_init(&vcpu->wait);
353 kvm_async_pf_vcpu_init(vcpu);
356 INIT_LIST_HEAD(&vcpu->blocked_vcpu_list);
358 kvm_vcpu_set_in_spin_loop(vcpu, false);
359 kvm_vcpu_set_dy_eligible(vcpu, false);
360 vcpu->preempted = false;
362 preempt_notifier_init(&vcpu->preempt_notifier, &kvm_preempt_ops);
365 void kvm_vcpu_destroy(struct kvm_vcpu *vcpu)
367 kvm_arch_vcpu_destroy(vcpu);
370 * No need for rcu_read_lock as VCPU_RUN is the only place that changes
371 * the vcpu->pid pointer, and at destruction time all file descriptors
374 put_pid(rcu_dereference_protected(vcpu->pid, 1));
376 free_page((unsigned long)vcpu->run);
377 kmem_cache_free(kvm_vcpu_cache, vcpu);
379 EXPORT_SYMBOL_GPL(kvm_vcpu_destroy);
381 #if defined(CONFIG_MMU_NOTIFIER) && defined(KVM_ARCH_WANT_MMU_NOTIFIER)
382 static inline struct kvm *mmu_notifier_to_kvm(struct mmu_notifier *mn)
384 return container_of(mn, struct kvm, mmu_notifier);
387 static void kvm_mmu_notifier_change_pte(struct mmu_notifier *mn,
388 struct mm_struct *mm,
389 unsigned long address,
392 struct kvm *kvm = mmu_notifier_to_kvm(mn);
395 idx = srcu_read_lock(&kvm->srcu);
396 spin_lock(&kvm->mmu_lock);
397 kvm->mmu_notifier_seq++;
399 if (kvm_set_spte_hva(kvm, address, pte))
400 kvm_flush_remote_tlbs(kvm);
402 spin_unlock(&kvm->mmu_lock);
403 srcu_read_unlock(&kvm->srcu, idx);
406 static int kvm_mmu_notifier_invalidate_range_start(struct mmu_notifier *mn,
407 const struct mmu_notifier_range *range)
409 struct kvm *kvm = mmu_notifier_to_kvm(mn);
410 int need_tlb_flush = 0, idx;
413 idx = srcu_read_lock(&kvm->srcu);
414 spin_lock(&kvm->mmu_lock);
416 * The count increase must become visible at unlock time as no
417 * spte can be established without taking the mmu_lock and
418 * count is also read inside the mmu_lock critical section.
420 kvm->mmu_notifier_count++;
421 need_tlb_flush = kvm_unmap_hva_range(kvm, range->start, range->end);
422 need_tlb_flush |= kvm->tlbs_dirty;
423 /* we've to flush the tlb before the pages can be freed */
425 kvm_flush_remote_tlbs(kvm);
427 spin_unlock(&kvm->mmu_lock);
429 ret = kvm_arch_mmu_notifier_invalidate_range(kvm, range->start,
431 mmu_notifier_range_blockable(range));
433 srcu_read_unlock(&kvm->srcu, idx);
438 static void kvm_mmu_notifier_invalidate_range_end(struct mmu_notifier *mn,
439 const struct mmu_notifier_range *range)
441 struct kvm *kvm = mmu_notifier_to_kvm(mn);
443 spin_lock(&kvm->mmu_lock);
445 * This sequence increase will notify the kvm page fault that
446 * the page that is going to be mapped in the spte could have
449 kvm->mmu_notifier_seq++;
452 * The above sequence increase must be visible before the
453 * below count decrease, which is ensured by the smp_wmb above
454 * in conjunction with the smp_rmb in mmu_notifier_retry().
456 kvm->mmu_notifier_count--;
457 spin_unlock(&kvm->mmu_lock);
459 BUG_ON(kvm->mmu_notifier_count < 0);
462 static int kvm_mmu_notifier_clear_flush_young(struct mmu_notifier *mn,
463 struct mm_struct *mm,
467 struct kvm *kvm = mmu_notifier_to_kvm(mn);
470 idx = srcu_read_lock(&kvm->srcu);
471 spin_lock(&kvm->mmu_lock);
473 young = kvm_age_hva(kvm, start, end);
475 kvm_flush_remote_tlbs(kvm);
477 spin_unlock(&kvm->mmu_lock);
478 srcu_read_unlock(&kvm->srcu, idx);
483 static int kvm_mmu_notifier_clear_young(struct mmu_notifier *mn,
484 struct mm_struct *mm,
488 struct kvm *kvm = mmu_notifier_to_kvm(mn);
491 idx = srcu_read_lock(&kvm->srcu);
492 spin_lock(&kvm->mmu_lock);
494 * Even though we do not flush TLB, this will still adversely
495 * affect performance on pre-Haswell Intel EPT, where there is
496 * no EPT Access Bit to clear so that we have to tear down EPT
497 * tables instead. If we find this unacceptable, we can always
498 * add a parameter to kvm_age_hva so that it effectively doesn't
499 * do anything on clear_young.
501 * Also note that currently we never issue secondary TLB flushes
502 * from clear_young, leaving this job up to the regular system
503 * cadence. If we find this inaccurate, we might come up with a
504 * more sophisticated heuristic later.
506 young = kvm_age_hva(kvm, start, end);
507 spin_unlock(&kvm->mmu_lock);
508 srcu_read_unlock(&kvm->srcu, idx);
513 static int kvm_mmu_notifier_test_young(struct mmu_notifier *mn,
514 struct mm_struct *mm,
515 unsigned long address)
517 struct kvm *kvm = mmu_notifier_to_kvm(mn);
520 idx = srcu_read_lock(&kvm->srcu);
521 spin_lock(&kvm->mmu_lock);
522 young = kvm_test_age_hva(kvm, address);
523 spin_unlock(&kvm->mmu_lock);
524 srcu_read_unlock(&kvm->srcu, idx);
529 static void kvm_mmu_notifier_release(struct mmu_notifier *mn,
530 struct mm_struct *mm)
532 struct kvm *kvm = mmu_notifier_to_kvm(mn);
535 idx = srcu_read_lock(&kvm->srcu);
536 kvm_arch_flush_shadow_all(kvm);
537 srcu_read_unlock(&kvm->srcu, idx);
540 static const struct mmu_notifier_ops kvm_mmu_notifier_ops = {
541 .invalidate_range_start = kvm_mmu_notifier_invalidate_range_start,
542 .invalidate_range_end = kvm_mmu_notifier_invalidate_range_end,
543 .clear_flush_young = kvm_mmu_notifier_clear_flush_young,
544 .clear_young = kvm_mmu_notifier_clear_young,
545 .test_young = kvm_mmu_notifier_test_young,
546 .change_pte = kvm_mmu_notifier_change_pte,
547 .release = kvm_mmu_notifier_release,
550 static int kvm_init_mmu_notifier(struct kvm *kvm)
552 kvm->mmu_notifier.ops = &kvm_mmu_notifier_ops;
553 return mmu_notifier_register(&kvm->mmu_notifier, current->mm);
556 #else /* !(CONFIG_MMU_NOTIFIER && KVM_ARCH_WANT_MMU_NOTIFIER) */
558 static int kvm_init_mmu_notifier(struct kvm *kvm)
563 #endif /* CONFIG_MMU_NOTIFIER && KVM_ARCH_WANT_MMU_NOTIFIER */
565 static struct kvm_memslots *kvm_alloc_memslots(void)
568 struct kvm_memslots *slots;
570 slots = kvzalloc(sizeof(struct kvm_memslots), GFP_KERNEL_ACCOUNT);
574 for (i = 0; i < KVM_MEM_SLOTS_NUM; i++)
575 slots->id_to_index[i] = -1;
580 static void kvm_destroy_dirty_bitmap(struct kvm_memory_slot *memslot)
582 if (!memslot->dirty_bitmap)
585 kvfree(memslot->dirty_bitmap);
586 memslot->dirty_bitmap = NULL;
589 static void kvm_free_memslot(struct kvm *kvm, struct kvm_memory_slot *slot)
591 kvm_destroy_dirty_bitmap(slot);
593 kvm_arch_free_memslot(kvm, slot);
599 static void kvm_free_memslots(struct kvm *kvm, struct kvm_memslots *slots)
601 struct kvm_memory_slot *memslot;
606 kvm_for_each_memslot(memslot, slots)
607 kvm_free_memslot(kvm, memslot);
612 static void kvm_destroy_vm_debugfs(struct kvm *kvm)
616 if (!kvm->debugfs_dentry)
619 debugfs_remove_recursive(kvm->debugfs_dentry);
621 if (kvm->debugfs_stat_data) {
622 for (i = 0; i < kvm_debugfs_num_entries; i++)
623 kfree(kvm->debugfs_stat_data[i]);
624 kfree(kvm->debugfs_stat_data);
628 static int kvm_create_vm_debugfs(struct kvm *kvm, int fd)
630 char dir_name[ITOA_MAX_LEN * 2];
631 struct kvm_stat_data *stat_data;
632 struct kvm_stats_debugfs_item *p;
634 if (!debugfs_initialized())
637 snprintf(dir_name, sizeof(dir_name), "%d-%d", task_pid_nr(current), fd);
638 kvm->debugfs_dentry = debugfs_create_dir(dir_name, kvm_debugfs_dir);
640 kvm->debugfs_stat_data = kcalloc(kvm_debugfs_num_entries,
641 sizeof(*kvm->debugfs_stat_data),
643 if (!kvm->debugfs_stat_data)
646 for (p = debugfs_entries; p->name; p++) {
647 stat_data = kzalloc(sizeof(*stat_data), GFP_KERNEL_ACCOUNT);
651 stat_data->kvm = kvm;
652 stat_data->dbgfs_item = p;
653 kvm->debugfs_stat_data[p - debugfs_entries] = stat_data;
654 debugfs_create_file(p->name, KVM_DBGFS_GET_MODE(p),
655 kvm->debugfs_dentry, stat_data,
662 * Called after the VM is otherwise initialized, but just before adding it to
665 int __weak kvm_arch_post_init_vm(struct kvm *kvm)
671 * Called just after removing the VM from the vm_list, but before doing any
674 void __weak kvm_arch_pre_destroy_vm(struct kvm *kvm)
678 static struct kvm *kvm_create_vm(unsigned long type)
680 struct kvm *kvm = kvm_arch_alloc_vm();
685 return ERR_PTR(-ENOMEM);
687 spin_lock_init(&kvm->mmu_lock);
689 kvm->mm = current->mm;
690 kvm_eventfd_init(kvm);
691 mutex_init(&kvm->lock);
692 mutex_init(&kvm->irq_lock);
693 mutex_init(&kvm->slots_lock);
694 INIT_LIST_HEAD(&kvm->devices);
696 BUILD_BUG_ON(KVM_MEM_SLOTS_NUM > SHRT_MAX);
698 if (init_srcu_struct(&kvm->srcu))
699 goto out_err_no_srcu;
700 if (init_srcu_struct(&kvm->irq_srcu))
701 goto out_err_no_irq_srcu;
703 refcount_set(&kvm->users_count, 1);
704 for (i = 0; i < KVM_ADDRESS_SPACE_NUM; i++) {
705 struct kvm_memslots *slots = kvm_alloc_memslots();
708 goto out_err_no_arch_destroy_vm;
709 /* Generations must be different for each address space. */
710 slots->generation = i;
711 rcu_assign_pointer(kvm->memslots[i], slots);
714 for (i = 0; i < KVM_NR_BUSES; i++) {
715 rcu_assign_pointer(kvm->buses[i],
716 kzalloc(sizeof(struct kvm_io_bus), GFP_KERNEL_ACCOUNT));
718 goto out_err_no_arch_destroy_vm;
721 kvm->max_halt_poll_ns = halt_poll_ns;
723 r = kvm_arch_init_vm(kvm, type);
725 goto out_err_no_arch_destroy_vm;
727 r = hardware_enable_all();
729 goto out_err_no_disable;
731 #ifdef CONFIG_HAVE_KVM_IRQFD
732 INIT_HLIST_HEAD(&kvm->irq_ack_notifier_list);
735 r = kvm_init_mmu_notifier(kvm);
737 goto out_err_no_mmu_notifier;
739 r = kvm_arch_post_init_vm(kvm);
743 mutex_lock(&kvm_lock);
744 list_add(&kvm->vm_list, &vm_list);
745 mutex_unlock(&kvm_lock);
747 preempt_notifier_inc();
752 #if defined(CONFIG_MMU_NOTIFIER) && defined(KVM_ARCH_WANT_MMU_NOTIFIER)
753 if (kvm->mmu_notifier.ops)
754 mmu_notifier_unregister(&kvm->mmu_notifier, current->mm);
756 out_err_no_mmu_notifier:
757 hardware_disable_all();
759 kvm_arch_destroy_vm(kvm);
760 out_err_no_arch_destroy_vm:
761 WARN_ON_ONCE(!refcount_dec_and_test(&kvm->users_count));
762 for (i = 0; i < KVM_NR_BUSES; i++)
763 kfree(kvm_get_bus(kvm, i));
764 for (i = 0; i < KVM_ADDRESS_SPACE_NUM; i++)
765 kvm_free_memslots(kvm, __kvm_memslots(kvm, i));
766 cleanup_srcu_struct(&kvm->irq_srcu);
768 cleanup_srcu_struct(&kvm->srcu);
770 kvm_arch_free_vm(kvm);
775 static void kvm_destroy_devices(struct kvm *kvm)
777 struct kvm_device *dev, *tmp;
780 * We do not need to take the kvm->lock here, because nobody else
781 * has a reference to the struct kvm at this point and therefore
782 * cannot access the devices list anyhow.
784 list_for_each_entry_safe(dev, tmp, &kvm->devices, vm_node) {
785 list_del(&dev->vm_node);
786 dev->ops->destroy(dev);
790 static void kvm_destroy_vm(struct kvm *kvm)
793 struct mm_struct *mm = kvm->mm;
795 kvm_uevent_notify_change(KVM_EVENT_DESTROY_VM, kvm);
796 kvm_destroy_vm_debugfs(kvm);
797 kvm_arch_sync_events(kvm);
798 mutex_lock(&kvm_lock);
799 list_del(&kvm->vm_list);
800 mutex_unlock(&kvm_lock);
801 kvm_arch_pre_destroy_vm(kvm);
803 kvm_free_irq_routing(kvm);
804 for (i = 0; i < KVM_NR_BUSES; i++) {
805 struct kvm_io_bus *bus = kvm_get_bus(kvm, i);
808 kvm_io_bus_destroy(bus);
809 kvm->buses[i] = NULL;
811 kvm_coalesced_mmio_free(kvm);
812 #if defined(CONFIG_MMU_NOTIFIER) && defined(KVM_ARCH_WANT_MMU_NOTIFIER)
813 mmu_notifier_unregister(&kvm->mmu_notifier, kvm->mm);
815 kvm_arch_flush_shadow_all(kvm);
817 kvm_arch_destroy_vm(kvm);
818 kvm_destroy_devices(kvm);
819 for (i = 0; i < KVM_ADDRESS_SPACE_NUM; i++)
820 kvm_free_memslots(kvm, __kvm_memslots(kvm, i));
821 cleanup_srcu_struct(&kvm->irq_srcu);
822 cleanup_srcu_struct(&kvm->srcu);
823 kvm_arch_free_vm(kvm);
824 preempt_notifier_dec();
825 hardware_disable_all();
829 void kvm_get_kvm(struct kvm *kvm)
831 refcount_inc(&kvm->users_count);
833 EXPORT_SYMBOL_GPL(kvm_get_kvm);
835 void kvm_put_kvm(struct kvm *kvm)
837 if (refcount_dec_and_test(&kvm->users_count))
840 EXPORT_SYMBOL_GPL(kvm_put_kvm);
843 * Used to put a reference that was taken on behalf of an object associated
844 * with a user-visible file descriptor, e.g. a vcpu or device, if installation
845 * of the new file descriptor fails and the reference cannot be transferred to
846 * its final owner. In such cases, the caller is still actively using @kvm and
847 * will fail miserably if the refcount unexpectedly hits zero.
849 void kvm_put_kvm_no_destroy(struct kvm *kvm)
851 WARN_ON(refcount_dec_and_test(&kvm->users_count));
853 EXPORT_SYMBOL_GPL(kvm_put_kvm_no_destroy);
855 static int kvm_vm_release(struct inode *inode, struct file *filp)
857 struct kvm *kvm = filp->private_data;
859 kvm_irqfd_release(kvm);
866 * Allocation size is twice as large as the actual dirty bitmap size.
867 * See kvm_vm_ioctl_get_dirty_log() why this is needed.
869 static int kvm_alloc_dirty_bitmap(struct kvm_memory_slot *memslot)
871 unsigned long dirty_bytes = 2 * kvm_dirty_bitmap_bytes(memslot);
873 memslot->dirty_bitmap = kvzalloc(dirty_bytes, GFP_KERNEL_ACCOUNT);
874 if (!memslot->dirty_bitmap)
881 * Delete a memslot by decrementing the number of used slots and shifting all
882 * other entries in the array forward one spot.
884 static inline void kvm_memslot_delete(struct kvm_memslots *slots,
885 struct kvm_memory_slot *memslot)
887 struct kvm_memory_slot *mslots = slots->memslots;
890 if (WARN_ON(slots->id_to_index[memslot->id] == -1))
895 if (atomic_read(&slots->lru_slot) >= slots->used_slots)
896 atomic_set(&slots->lru_slot, 0);
898 for (i = slots->id_to_index[memslot->id]; i < slots->used_slots; i++) {
899 mslots[i] = mslots[i + 1];
900 slots->id_to_index[mslots[i].id] = i;
902 mslots[i] = *memslot;
903 slots->id_to_index[memslot->id] = -1;
907 * "Insert" a new memslot by incrementing the number of used slots. Returns
908 * the new slot's initial index into the memslots array.
910 static inline int kvm_memslot_insert_back(struct kvm_memslots *slots)
912 return slots->used_slots++;
916 * Move a changed memslot backwards in the array by shifting existing slots
917 * with a higher GFN toward the front of the array. Note, the changed memslot
918 * itself is not preserved in the array, i.e. not swapped at this time, only
919 * its new index into the array is tracked. Returns the changed memslot's
920 * current index into the memslots array.
922 static inline int kvm_memslot_move_backward(struct kvm_memslots *slots,
923 struct kvm_memory_slot *memslot)
925 struct kvm_memory_slot *mslots = slots->memslots;
928 if (WARN_ON_ONCE(slots->id_to_index[memslot->id] == -1) ||
929 WARN_ON_ONCE(!slots->used_slots))
933 * Move the target memslot backward in the array by shifting existing
934 * memslots with a higher GFN (than the target memslot) towards the
935 * front of the array.
937 for (i = slots->id_to_index[memslot->id]; i < slots->used_slots - 1; i++) {
938 if (memslot->base_gfn > mslots[i + 1].base_gfn)
941 WARN_ON_ONCE(memslot->base_gfn == mslots[i + 1].base_gfn);
943 /* Shift the next memslot forward one and update its index. */
944 mslots[i] = mslots[i + 1];
945 slots->id_to_index[mslots[i].id] = i;
951 * Move a changed memslot forwards in the array by shifting existing slots with
952 * a lower GFN toward the back of the array. Note, the changed memslot itself
953 * is not preserved in the array, i.e. not swapped at this time, only its new
954 * index into the array is tracked. Returns the changed memslot's final index
955 * into the memslots array.
957 static inline int kvm_memslot_move_forward(struct kvm_memslots *slots,
958 struct kvm_memory_slot *memslot,
961 struct kvm_memory_slot *mslots = slots->memslots;
964 for (i = start; i > 0; i--) {
965 if (memslot->base_gfn < mslots[i - 1].base_gfn)
968 WARN_ON_ONCE(memslot->base_gfn == mslots[i - 1].base_gfn);
970 /* Shift the next memslot back one and update its index. */
971 mslots[i] = mslots[i - 1];
972 slots->id_to_index[mslots[i].id] = i;
978 * Re-sort memslots based on their GFN to account for an added, deleted, or
979 * moved memslot. Sorting memslots by GFN allows using a binary search during
982 * IMPORTANT: Slots are sorted from highest GFN to lowest GFN! I.e. the entry
983 * at memslots[0] has the highest GFN.
985 * The sorting algorithm takes advantage of having initially sorted memslots
986 * and knowing the position of the changed memslot. Sorting is also optimized
987 * by not swapping the updated memslot and instead only shifting other memslots
988 * and tracking the new index for the update memslot. Only once its final
989 * index is known is the updated memslot copied into its position in the array.
991 * - When deleting a memslot, the deleted memslot simply needs to be moved to
992 * the end of the array.
994 * - When creating a memslot, the algorithm "inserts" the new memslot at the
995 * end of the array and then it forward to its correct location.
997 * - When moving a memslot, the algorithm first moves the updated memslot
998 * backward to handle the scenario where the memslot's GFN was changed to a
999 * lower value. update_memslots() then falls through and runs the same flow
1000 * as creating a memslot to move the memslot forward to handle the scenario
1001 * where its GFN was changed to a higher value.
1003 * Note, slots are sorted from highest->lowest instead of lowest->highest for
1004 * historical reasons. Originally, invalid memslots where denoted by having
1005 * GFN=0, thus sorting from highest->lowest naturally sorted invalid memslots
1006 * to the end of the array. The current algorithm uses dedicated logic to
1007 * delete a memslot and thus does not rely on invalid memslots having GFN=0.
1009 * The other historical motiviation for highest->lowest was to improve the
1010 * performance of memslot lookup. KVM originally used a linear search starting
1011 * at memslots[0]. On x86, the largest memslot usually has one of the highest,
1012 * if not *the* highest, GFN, as the bulk of the guest's RAM is located in a
1013 * single memslot above the 4gb boundary. As the largest memslot is also the
1014 * most likely to be referenced, sorting it to the front of the array was
1015 * advantageous. The current binary search starts from the middle of the array
1016 * and uses an LRU pointer to improve performance for all memslots and GFNs.
1018 static void update_memslots(struct kvm_memslots *slots,
1019 struct kvm_memory_slot *memslot,
1020 enum kvm_mr_change change)
1024 if (change == KVM_MR_DELETE) {
1025 kvm_memslot_delete(slots, memslot);
1027 if (change == KVM_MR_CREATE)
1028 i = kvm_memslot_insert_back(slots);
1030 i = kvm_memslot_move_backward(slots, memslot);
1031 i = kvm_memslot_move_forward(slots, memslot, i);
1034 * Copy the memslot to its new position in memslots and update
1035 * its index accordingly.
1037 slots->memslots[i] = *memslot;
1038 slots->id_to_index[memslot->id] = i;
1042 static int check_memory_region_flags(const struct kvm_userspace_memory_region *mem)
1044 u32 valid_flags = KVM_MEM_LOG_DIRTY_PAGES;
1046 #ifdef __KVM_HAVE_READONLY_MEM
1047 valid_flags |= KVM_MEM_READONLY;
1050 if (mem->flags & ~valid_flags)
1056 static struct kvm_memslots *install_new_memslots(struct kvm *kvm,
1057 int as_id, struct kvm_memslots *slots)
1059 struct kvm_memslots *old_memslots = __kvm_memslots(kvm, as_id);
1060 u64 gen = old_memslots->generation;
1062 WARN_ON(gen & KVM_MEMSLOT_GEN_UPDATE_IN_PROGRESS);
1063 slots->generation = gen | KVM_MEMSLOT_GEN_UPDATE_IN_PROGRESS;
1065 rcu_assign_pointer(kvm->memslots[as_id], slots);
1066 synchronize_srcu_expedited(&kvm->srcu);
1069 * Increment the new memslot generation a second time, dropping the
1070 * update in-progress flag and incrementing the generation based on
1071 * the number of address spaces. This provides a unique and easily
1072 * identifiable generation number while the memslots are in flux.
1074 gen = slots->generation & ~KVM_MEMSLOT_GEN_UPDATE_IN_PROGRESS;
1077 * Generations must be unique even across address spaces. We do not need
1078 * a global counter for that, instead the generation space is evenly split
1079 * across address spaces. For example, with two address spaces, address
1080 * space 0 will use generations 0, 2, 4, ... while address space 1 will
1081 * use generations 1, 3, 5, ...
1083 gen += KVM_ADDRESS_SPACE_NUM;
1085 kvm_arch_memslots_updated(kvm, gen);
1087 slots->generation = gen;
1089 return old_memslots;
1093 * Note, at a minimum, the current number of used slots must be allocated, even
1094 * when deleting a memslot, as we need a complete duplicate of the memslots for
1095 * use when invalidating a memslot prior to deleting/moving the memslot.
1097 static struct kvm_memslots *kvm_dup_memslots(struct kvm_memslots *old,
1098 enum kvm_mr_change change)
1100 struct kvm_memslots *slots;
1101 size_t old_size, new_size;
1103 old_size = sizeof(struct kvm_memslots) +
1104 (sizeof(struct kvm_memory_slot) * old->used_slots);
1106 if (change == KVM_MR_CREATE)
1107 new_size = old_size + sizeof(struct kvm_memory_slot);
1109 new_size = old_size;
1111 slots = kvzalloc(new_size, GFP_KERNEL_ACCOUNT);
1113 memcpy(slots, old, old_size);
1118 static int kvm_set_memslot(struct kvm *kvm,
1119 const struct kvm_userspace_memory_region *mem,
1120 struct kvm_memory_slot *old,
1121 struct kvm_memory_slot *new, int as_id,
1122 enum kvm_mr_change change)
1124 struct kvm_memory_slot *slot;
1125 struct kvm_memslots *slots;
1128 slots = kvm_dup_memslots(__kvm_memslots(kvm, as_id), change);
1132 if (change == KVM_MR_DELETE || change == KVM_MR_MOVE) {
1134 * Note, the INVALID flag needs to be in the appropriate entry
1135 * in the freshly allocated memslots, not in @old or @new.
1137 slot = id_to_memslot(slots, old->id);
1138 slot->flags |= KVM_MEMSLOT_INVALID;
1141 * We can re-use the old memslots, the only difference from the
1142 * newly installed memslots is the invalid flag, which will get
1143 * dropped by update_memslots anyway. We'll also revert to the
1144 * old memslots if preparing the new memory region fails.
1146 slots = install_new_memslots(kvm, as_id, slots);
1148 /* From this point no new shadow pages pointing to a deleted,
1149 * or moved, memslot will be created.
1151 * validation of sp->gfn happens in:
1152 * - gfn_to_hva (kvm_read_guest, gfn_to_pfn)
1153 * - kvm_is_visible_gfn (mmu_check_root)
1155 kvm_arch_flush_shadow_memslot(kvm, slot);
1158 r = kvm_arch_prepare_memory_region(kvm, new, mem, change);
1162 update_memslots(slots, new, change);
1163 slots = install_new_memslots(kvm, as_id, slots);
1165 kvm_arch_commit_memory_region(kvm, mem, old, new, change);
1171 if (change == KVM_MR_DELETE || change == KVM_MR_MOVE)
1172 slots = install_new_memslots(kvm, as_id, slots);
1177 static int kvm_delete_memslot(struct kvm *kvm,
1178 const struct kvm_userspace_memory_region *mem,
1179 struct kvm_memory_slot *old, int as_id)
1181 struct kvm_memory_slot new;
1187 memset(&new, 0, sizeof(new));
1190 r = kvm_set_memslot(kvm, mem, old, &new, as_id, KVM_MR_DELETE);
1194 kvm_free_memslot(kvm, old);
1199 * Allocate some memory and give it an address in the guest physical address
1202 * Discontiguous memory is allowed, mostly for framebuffers.
1204 * Must be called holding kvm->slots_lock for write.
1206 int __kvm_set_memory_region(struct kvm *kvm,
1207 const struct kvm_userspace_memory_region *mem)
1209 struct kvm_memory_slot old, new;
1210 struct kvm_memory_slot *tmp;
1211 enum kvm_mr_change change;
1215 r = check_memory_region_flags(mem);
1219 as_id = mem->slot >> 16;
1220 id = (u16)mem->slot;
1222 /* General sanity checks */
1223 if (mem->memory_size & (PAGE_SIZE - 1))
1225 if (mem->guest_phys_addr & (PAGE_SIZE - 1))
1227 /* We can read the guest memory with __xxx_user() later on. */
1228 if ((mem->userspace_addr & (PAGE_SIZE - 1)) ||
1229 !access_ok((void __user *)(unsigned long)mem->userspace_addr,
1232 if (as_id >= KVM_ADDRESS_SPACE_NUM || id >= KVM_MEM_SLOTS_NUM)
1234 if (mem->guest_phys_addr + mem->memory_size < mem->guest_phys_addr)
1238 * Make a full copy of the old memslot, the pointer will become stale
1239 * when the memslots are re-sorted by update_memslots(), and the old
1240 * memslot needs to be referenced after calling update_memslots(), e.g.
1241 * to free its resources and for arch specific behavior.
1243 tmp = id_to_memslot(__kvm_memslots(kvm, as_id), id);
1248 memset(&old, 0, sizeof(old));
1252 if (!mem->memory_size)
1253 return kvm_delete_memslot(kvm, mem, &old, as_id);
1256 new.base_gfn = mem->guest_phys_addr >> PAGE_SHIFT;
1257 new.npages = mem->memory_size >> PAGE_SHIFT;
1258 new.flags = mem->flags;
1259 new.userspace_addr = mem->userspace_addr;
1261 if (new.npages > KVM_MEM_MAX_NR_PAGES)
1265 change = KVM_MR_CREATE;
1266 new.dirty_bitmap = NULL;
1267 memset(&new.arch, 0, sizeof(new.arch));
1268 } else { /* Modify an existing slot. */
1269 if ((new.userspace_addr != old.userspace_addr) ||
1270 (new.npages != old.npages) ||
1271 ((new.flags ^ old.flags) & KVM_MEM_READONLY))
1274 if (new.base_gfn != old.base_gfn)
1275 change = KVM_MR_MOVE;
1276 else if (new.flags != old.flags)
1277 change = KVM_MR_FLAGS_ONLY;
1278 else /* Nothing to change. */
1281 /* Copy dirty_bitmap and arch from the current memslot. */
1282 new.dirty_bitmap = old.dirty_bitmap;
1283 memcpy(&new.arch, &old.arch, sizeof(new.arch));
1286 if ((change == KVM_MR_CREATE) || (change == KVM_MR_MOVE)) {
1287 /* Check for overlaps */
1288 kvm_for_each_memslot(tmp, __kvm_memslots(kvm, as_id)) {
1291 if (!((new.base_gfn + new.npages <= tmp->base_gfn) ||
1292 (new.base_gfn >= tmp->base_gfn + tmp->npages)))
1297 /* Allocate/free page dirty bitmap as needed */
1298 if (!(new.flags & KVM_MEM_LOG_DIRTY_PAGES))
1299 new.dirty_bitmap = NULL;
1300 else if (!new.dirty_bitmap) {
1301 r = kvm_alloc_dirty_bitmap(&new);
1305 if (kvm_dirty_log_manual_protect_and_init_set(kvm))
1306 bitmap_set(new.dirty_bitmap, 0, new.npages);
1309 r = kvm_set_memslot(kvm, mem, &old, &new, as_id, change);
1313 if (old.dirty_bitmap && !new.dirty_bitmap)
1314 kvm_destroy_dirty_bitmap(&old);
1318 if (new.dirty_bitmap && !old.dirty_bitmap)
1319 kvm_destroy_dirty_bitmap(&new);
1322 EXPORT_SYMBOL_GPL(__kvm_set_memory_region);
1324 int kvm_set_memory_region(struct kvm *kvm,
1325 const struct kvm_userspace_memory_region *mem)
1329 mutex_lock(&kvm->slots_lock);
1330 r = __kvm_set_memory_region(kvm, mem);
1331 mutex_unlock(&kvm->slots_lock);
1334 EXPORT_SYMBOL_GPL(kvm_set_memory_region);
1336 static int kvm_vm_ioctl_set_memory_region(struct kvm *kvm,
1337 struct kvm_userspace_memory_region *mem)
1339 if ((u16)mem->slot >= KVM_USER_MEM_SLOTS)
1342 return kvm_set_memory_region(kvm, mem);
1345 #ifndef CONFIG_KVM_GENERIC_DIRTYLOG_READ_PROTECT
1347 * kvm_get_dirty_log - get a snapshot of dirty pages
1348 * @kvm: pointer to kvm instance
1349 * @log: slot id and address to which we copy the log
1350 * @is_dirty: set to '1' if any dirty pages were found
1351 * @memslot: set to the associated memslot, always valid on success
1353 int kvm_get_dirty_log(struct kvm *kvm, struct kvm_dirty_log *log,
1354 int *is_dirty, struct kvm_memory_slot **memslot)
1356 struct kvm_memslots *slots;
1359 unsigned long any = 0;
1364 as_id = log->slot >> 16;
1365 id = (u16)log->slot;
1366 if (as_id >= KVM_ADDRESS_SPACE_NUM || id >= KVM_USER_MEM_SLOTS)
1369 slots = __kvm_memslots(kvm, as_id);
1370 *memslot = id_to_memslot(slots, id);
1371 if (!(*memslot) || !(*memslot)->dirty_bitmap)
1374 kvm_arch_sync_dirty_log(kvm, *memslot);
1376 n = kvm_dirty_bitmap_bytes(*memslot);
1378 for (i = 0; !any && i < n/sizeof(long); ++i)
1379 any = (*memslot)->dirty_bitmap[i];
1381 if (copy_to_user(log->dirty_bitmap, (*memslot)->dirty_bitmap, n))
1388 EXPORT_SYMBOL_GPL(kvm_get_dirty_log);
1390 #else /* CONFIG_KVM_GENERIC_DIRTYLOG_READ_PROTECT */
1392 * kvm_get_dirty_log_protect - get a snapshot of dirty pages
1393 * and reenable dirty page tracking for the corresponding pages.
1394 * @kvm: pointer to kvm instance
1395 * @log: slot id and address to which we copy the log
1397 * We need to keep it in mind that VCPU threads can write to the bitmap
1398 * concurrently. So, to avoid losing track of dirty pages we keep the
1401 * 1. Take a snapshot of the bit and clear it if needed.
1402 * 2. Write protect the corresponding page.
1403 * 3. Copy the snapshot to the userspace.
1404 * 4. Upon return caller flushes TLB's if needed.
1406 * Between 2 and 4, the guest may write to the page using the remaining TLB
1407 * entry. This is not a problem because the page is reported dirty using
1408 * the snapshot taken before and step 4 ensures that writes done after
1409 * exiting to userspace will be logged for the next call.
1412 static int kvm_get_dirty_log_protect(struct kvm *kvm, struct kvm_dirty_log *log)
1414 struct kvm_memslots *slots;
1415 struct kvm_memory_slot *memslot;
1418 unsigned long *dirty_bitmap;
1419 unsigned long *dirty_bitmap_buffer;
1422 as_id = log->slot >> 16;
1423 id = (u16)log->slot;
1424 if (as_id >= KVM_ADDRESS_SPACE_NUM || id >= KVM_USER_MEM_SLOTS)
1427 slots = __kvm_memslots(kvm, as_id);
1428 memslot = id_to_memslot(slots, id);
1429 if (!memslot || !memslot->dirty_bitmap)
1432 dirty_bitmap = memslot->dirty_bitmap;
1434 kvm_arch_sync_dirty_log(kvm, memslot);
1436 n = kvm_dirty_bitmap_bytes(memslot);
1438 if (kvm->manual_dirty_log_protect) {
1440 * Unlike kvm_get_dirty_log, we always return false in *flush,
1441 * because no flush is needed until KVM_CLEAR_DIRTY_LOG. There
1442 * is some code duplication between this function and
1443 * kvm_get_dirty_log, but hopefully all architecture
1444 * transition to kvm_get_dirty_log_protect and kvm_get_dirty_log
1445 * can be eliminated.
1447 dirty_bitmap_buffer = dirty_bitmap;
1449 dirty_bitmap_buffer = kvm_second_dirty_bitmap(memslot);
1450 memset(dirty_bitmap_buffer, 0, n);
1452 spin_lock(&kvm->mmu_lock);
1453 for (i = 0; i < n / sizeof(long); i++) {
1457 if (!dirty_bitmap[i])
1461 mask = xchg(&dirty_bitmap[i], 0);
1462 dirty_bitmap_buffer[i] = mask;
1464 offset = i * BITS_PER_LONG;
1465 kvm_arch_mmu_enable_log_dirty_pt_masked(kvm, memslot,
1468 spin_unlock(&kvm->mmu_lock);
1472 kvm_arch_flush_remote_tlbs_memslot(kvm, memslot);
1474 if (copy_to_user(log->dirty_bitmap, dirty_bitmap_buffer, n))
1481 * kvm_vm_ioctl_get_dirty_log - get and clear the log of dirty pages in a slot
1482 * @kvm: kvm instance
1483 * @log: slot id and address to which we copy the log
1485 * Steps 1-4 below provide general overview of dirty page logging. See
1486 * kvm_get_dirty_log_protect() function description for additional details.
1488 * We call kvm_get_dirty_log_protect() to handle steps 1-3, upon return we
1489 * always flush the TLB (step 4) even if previous step failed and the dirty
1490 * bitmap may be corrupt. Regardless of previous outcome the KVM logging API
1491 * does not preclude user space subsequent dirty log read. Flushing TLB ensures
1492 * writes will be marked dirty for next log read.
1494 * 1. Take a snapshot of the bit and clear it if needed.
1495 * 2. Write protect the corresponding page.
1496 * 3. Copy the snapshot to the userspace.
1497 * 4. Flush TLB's if needed.
1499 static int kvm_vm_ioctl_get_dirty_log(struct kvm *kvm,
1500 struct kvm_dirty_log *log)
1504 mutex_lock(&kvm->slots_lock);
1506 r = kvm_get_dirty_log_protect(kvm, log);
1508 mutex_unlock(&kvm->slots_lock);
1513 * kvm_clear_dirty_log_protect - clear dirty bits in the bitmap
1514 * and reenable dirty page tracking for the corresponding pages.
1515 * @kvm: pointer to kvm instance
1516 * @log: slot id and address from which to fetch the bitmap of dirty pages
1518 static int kvm_clear_dirty_log_protect(struct kvm *kvm,
1519 struct kvm_clear_dirty_log *log)
1521 struct kvm_memslots *slots;
1522 struct kvm_memory_slot *memslot;
1526 unsigned long *dirty_bitmap;
1527 unsigned long *dirty_bitmap_buffer;
1530 as_id = log->slot >> 16;
1531 id = (u16)log->slot;
1532 if (as_id >= KVM_ADDRESS_SPACE_NUM || id >= KVM_USER_MEM_SLOTS)
1535 if (log->first_page & 63)
1538 slots = __kvm_memslots(kvm, as_id);
1539 memslot = id_to_memslot(slots, id);
1540 if (!memslot || !memslot->dirty_bitmap)
1543 dirty_bitmap = memslot->dirty_bitmap;
1545 n = ALIGN(log->num_pages, BITS_PER_LONG) / 8;
1547 if (log->first_page > memslot->npages ||
1548 log->num_pages > memslot->npages - log->first_page ||
1549 (log->num_pages < memslot->npages - log->first_page && (log->num_pages & 63)))
1552 kvm_arch_sync_dirty_log(kvm, memslot);
1555 dirty_bitmap_buffer = kvm_second_dirty_bitmap(memslot);
1556 if (copy_from_user(dirty_bitmap_buffer, log->dirty_bitmap, n))
1559 spin_lock(&kvm->mmu_lock);
1560 for (offset = log->first_page, i = offset / BITS_PER_LONG,
1561 n = DIV_ROUND_UP(log->num_pages, BITS_PER_LONG); n--;
1562 i++, offset += BITS_PER_LONG) {
1563 unsigned long mask = *dirty_bitmap_buffer++;
1564 atomic_long_t *p = (atomic_long_t *) &dirty_bitmap[i];
1568 mask &= atomic_long_fetch_andnot(mask, p);
1571 * mask contains the bits that really have been cleared. This
1572 * never includes any bits beyond the length of the memslot (if
1573 * the length is not aligned to 64 pages), therefore it is not
1574 * a problem if userspace sets them in log->dirty_bitmap.
1578 kvm_arch_mmu_enable_log_dirty_pt_masked(kvm, memslot,
1582 spin_unlock(&kvm->mmu_lock);
1585 kvm_arch_flush_remote_tlbs_memslot(kvm, memslot);
1590 static int kvm_vm_ioctl_clear_dirty_log(struct kvm *kvm,
1591 struct kvm_clear_dirty_log *log)
1595 mutex_lock(&kvm->slots_lock);
1597 r = kvm_clear_dirty_log_protect(kvm, log);
1599 mutex_unlock(&kvm->slots_lock);
1602 #endif /* CONFIG_KVM_GENERIC_DIRTYLOG_READ_PROTECT */
1604 struct kvm_memory_slot *gfn_to_memslot(struct kvm *kvm, gfn_t gfn)
1606 return __gfn_to_memslot(kvm_memslots(kvm), gfn);
1608 EXPORT_SYMBOL_GPL(gfn_to_memslot);
1610 struct kvm_memory_slot *kvm_vcpu_gfn_to_memslot(struct kvm_vcpu *vcpu, gfn_t gfn)
1612 return __gfn_to_memslot(kvm_vcpu_memslots(vcpu), gfn);
1614 EXPORT_SYMBOL_GPL(kvm_vcpu_gfn_to_memslot);
1616 bool kvm_is_visible_gfn(struct kvm *kvm, gfn_t gfn)
1618 struct kvm_memory_slot *memslot = gfn_to_memslot(kvm, gfn);
1620 return kvm_is_visible_memslot(memslot);
1622 EXPORT_SYMBOL_GPL(kvm_is_visible_gfn);
1624 unsigned long kvm_host_page_size(struct kvm_vcpu *vcpu, gfn_t gfn)
1626 struct vm_area_struct *vma;
1627 unsigned long addr, size;
1631 addr = kvm_vcpu_gfn_to_hva_prot(vcpu, gfn, NULL);
1632 if (kvm_is_error_hva(addr))
1635 down_read(¤t->mm->mmap_sem);
1636 vma = find_vma(current->mm, addr);
1640 size = vma_kernel_pagesize(vma);
1643 up_read(¤t->mm->mmap_sem);
1648 static bool memslot_is_readonly(struct kvm_memory_slot *slot)
1650 return slot->flags & KVM_MEM_READONLY;
1653 static unsigned long __gfn_to_hva_many(struct kvm_memory_slot *slot, gfn_t gfn,
1654 gfn_t *nr_pages, bool write)
1656 if (!slot || slot->flags & KVM_MEMSLOT_INVALID)
1657 return KVM_HVA_ERR_BAD;
1659 if (memslot_is_readonly(slot) && write)
1660 return KVM_HVA_ERR_RO_BAD;
1663 *nr_pages = slot->npages - (gfn - slot->base_gfn);
1665 return __gfn_to_hva_memslot(slot, gfn);
1668 static unsigned long gfn_to_hva_many(struct kvm_memory_slot *slot, gfn_t gfn,
1671 return __gfn_to_hva_many(slot, gfn, nr_pages, true);
1674 unsigned long gfn_to_hva_memslot(struct kvm_memory_slot *slot,
1677 return gfn_to_hva_many(slot, gfn, NULL);
1679 EXPORT_SYMBOL_GPL(gfn_to_hva_memslot);
1681 unsigned long gfn_to_hva(struct kvm *kvm, gfn_t gfn)
1683 return gfn_to_hva_many(gfn_to_memslot(kvm, gfn), gfn, NULL);
1685 EXPORT_SYMBOL_GPL(gfn_to_hva);
1687 unsigned long kvm_vcpu_gfn_to_hva(struct kvm_vcpu *vcpu, gfn_t gfn)
1689 return gfn_to_hva_many(kvm_vcpu_gfn_to_memslot(vcpu, gfn), gfn, NULL);
1691 EXPORT_SYMBOL_GPL(kvm_vcpu_gfn_to_hva);
1694 * Return the hva of a @gfn and the R/W attribute if possible.
1696 * @slot: the kvm_memory_slot which contains @gfn
1697 * @gfn: the gfn to be translated
1698 * @writable: used to return the read/write attribute of the @slot if the hva
1699 * is valid and @writable is not NULL
1701 unsigned long gfn_to_hva_memslot_prot(struct kvm_memory_slot *slot,
1702 gfn_t gfn, bool *writable)
1704 unsigned long hva = __gfn_to_hva_many(slot, gfn, NULL, false);
1706 if (!kvm_is_error_hva(hva) && writable)
1707 *writable = !memslot_is_readonly(slot);
1712 unsigned long gfn_to_hva_prot(struct kvm *kvm, gfn_t gfn, bool *writable)
1714 struct kvm_memory_slot *slot = gfn_to_memslot(kvm, gfn);
1716 return gfn_to_hva_memslot_prot(slot, gfn, writable);
1719 unsigned long kvm_vcpu_gfn_to_hva_prot(struct kvm_vcpu *vcpu, gfn_t gfn, bool *writable)
1721 struct kvm_memory_slot *slot = kvm_vcpu_gfn_to_memslot(vcpu, gfn);
1723 return gfn_to_hva_memslot_prot(slot, gfn, writable);
1726 static inline int check_user_page_hwpoison(unsigned long addr)
1728 int rc, flags = FOLL_HWPOISON | FOLL_WRITE;
1730 rc = get_user_pages(addr, 1, flags, NULL, NULL);
1731 return rc == -EHWPOISON;
1735 * The fast path to get the writable pfn which will be stored in @pfn,
1736 * true indicates success, otherwise false is returned. It's also the
1737 * only part that runs if we can in atomic context.
1739 static bool hva_to_pfn_fast(unsigned long addr, bool write_fault,
1740 bool *writable, kvm_pfn_t *pfn)
1742 struct page *page[1];
1745 * Fast pin a writable pfn only if it is a write fault request
1746 * or the caller allows to map a writable pfn for a read fault
1749 if (!(write_fault || writable))
1752 if (get_user_page_fast_only(addr, FOLL_WRITE, page)) {
1753 *pfn = page_to_pfn(page[0]);
1764 * The slow path to get the pfn of the specified host virtual address,
1765 * 1 indicates success, -errno is returned if error is detected.
1767 static int hva_to_pfn_slow(unsigned long addr, bool *async, bool write_fault,
1768 bool *writable, kvm_pfn_t *pfn)
1770 unsigned int flags = FOLL_HWPOISON;
1777 *writable = write_fault;
1780 flags |= FOLL_WRITE;
1782 flags |= FOLL_NOWAIT;
1784 npages = get_user_pages_unlocked(addr, 1, &page, flags);
1788 /* map read fault as writable if possible */
1789 if (unlikely(!write_fault) && writable) {
1792 if (get_user_page_fast_only(addr, FOLL_WRITE, &wpage)) {
1798 *pfn = page_to_pfn(page);
1802 static bool vma_is_valid(struct vm_area_struct *vma, bool write_fault)
1804 if (unlikely(!(vma->vm_flags & VM_READ)))
1807 if (write_fault && (unlikely(!(vma->vm_flags & VM_WRITE))))
1813 static int hva_to_pfn_remapped(struct vm_area_struct *vma,
1814 unsigned long addr, bool *async,
1815 bool write_fault, bool *writable,
1821 r = follow_pfn(vma, addr, &pfn);
1824 * get_user_pages fails for VM_IO and VM_PFNMAP vmas and does
1825 * not call the fault handler, so do it here.
1827 bool unlocked = false;
1828 r = fixup_user_fault(current, current->mm, addr,
1829 (write_fault ? FAULT_FLAG_WRITE : 0),
1836 r = follow_pfn(vma, addr, &pfn);
1846 * Get a reference here because callers of *hva_to_pfn* and
1847 * *gfn_to_pfn* ultimately call kvm_release_pfn_clean on the
1848 * returned pfn. This is only needed if the VMA has VM_MIXEDMAP
1849 * set, but the kvm_get_pfn/kvm_release_pfn_clean pair will
1850 * simply do nothing for reserved pfns.
1852 * Whoever called remap_pfn_range is also going to call e.g.
1853 * unmap_mapping_range before the underlying pages are freed,
1854 * causing a call to our MMU notifier.
1863 * Pin guest page in memory and return its pfn.
1864 * @addr: host virtual address which maps memory to the guest
1865 * @atomic: whether this function can sleep
1866 * @async: whether this function need to wait IO complete if the
1867 * host page is not in the memory
1868 * @write_fault: whether we should get a writable host page
1869 * @writable: whether it allows to map a writable host page for !@write_fault
1871 * The function will map a writable host page for these two cases:
1872 * 1): @write_fault = true
1873 * 2): @write_fault = false && @writable, @writable will tell the caller
1874 * whether the mapping is writable.
1876 static kvm_pfn_t hva_to_pfn(unsigned long addr, bool atomic, bool *async,
1877 bool write_fault, bool *writable)
1879 struct vm_area_struct *vma;
1883 /* we can do it either atomically or asynchronously, not both */
1884 BUG_ON(atomic && async);
1886 if (hva_to_pfn_fast(addr, write_fault, writable, &pfn))
1890 return KVM_PFN_ERR_FAULT;
1892 npages = hva_to_pfn_slow(addr, async, write_fault, writable, &pfn);
1896 down_read(¤t->mm->mmap_sem);
1897 if (npages == -EHWPOISON ||
1898 (!async && check_user_page_hwpoison(addr))) {
1899 pfn = KVM_PFN_ERR_HWPOISON;
1904 vma = find_vma_intersection(current->mm, addr, addr + 1);
1907 pfn = KVM_PFN_ERR_FAULT;
1908 else if (vma->vm_flags & (VM_IO | VM_PFNMAP)) {
1909 r = hva_to_pfn_remapped(vma, addr, async, write_fault, writable, &pfn);
1913 pfn = KVM_PFN_ERR_FAULT;
1915 if (async && vma_is_valid(vma, write_fault))
1917 pfn = KVM_PFN_ERR_FAULT;
1920 up_read(¤t->mm->mmap_sem);
1924 kvm_pfn_t __gfn_to_pfn_memslot(struct kvm_memory_slot *slot, gfn_t gfn,
1925 bool atomic, bool *async, bool write_fault,
1928 unsigned long addr = __gfn_to_hva_many(slot, gfn, NULL, write_fault);
1930 if (addr == KVM_HVA_ERR_RO_BAD) {
1933 return KVM_PFN_ERR_RO_FAULT;
1936 if (kvm_is_error_hva(addr)) {
1939 return KVM_PFN_NOSLOT;
1942 /* Do not map writable pfn in the readonly memslot. */
1943 if (writable && memslot_is_readonly(slot)) {
1948 return hva_to_pfn(addr, atomic, async, write_fault,
1951 EXPORT_SYMBOL_GPL(__gfn_to_pfn_memslot);
1953 kvm_pfn_t gfn_to_pfn_prot(struct kvm *kvm, gfn_t gfn, bool write_fault,
1956 return __gfn_to_pfn_memslot(gfn_to_memslot(kvm, gfn), gfn, false, NULL,
1957 write_fault, writable);
1959 EXPORT_SYMBOL_GPL(gfn_to_pfn_prot);
1961 kvm_pfn_t gfn_to_pfn_memslot(struct kvm_memory_slot *slot, gfn_t gfn)
1963 return __gfn_to_pfn_memslot(slot, gfn, false, NULL, true, NULL);
1965 EXPORT_SYMBOL_GPL(gfn_to_pfn_memslot);
1967 kvm_pfn_t gfn_to_pfn_memslot_atomic(struct kvm_memory_slot *slot, gfn_t gfn)
1969 return __gfn_to_pfn_memslot(slot, gfn, true, NULL, true, NULL);
1971 EXPORT_SYMBOL_GPL(gfn_to_pfn_memslot_atomic);
1973 kvm_pfn_t kvm_vcpu_gfn_to_pfn_atomic(struct kvm_vcpu *vcpu, gfn_t gfn)
1975 return gfn_to_pfn_memslot_atomic(kvm_vcpu_gfn_to_memslot(vcpu, gfn), gfn);
1977 EXPORT_SYMBOL_GPL(kvm_vcpu_gfn_to_pfn_atomic);
1979 kvm_pfn_t gfn_to_pfn(struct kvm *kvm, gfn_t gfn)
1981 return gfn_to_pfn_memslot(gfn_to_memslot(kvm, gfn), gfn);
1983 EXPORT_SYMBOL_GPL(gfn_to_pfn);
1985 kvm_pfn_t kvm_vcpu_gfn_to_pfn(struct kvm_vcpu *vcpu, gfn_t gfn)
1987 return gfn_to_pfn_memslot(kvm_vcpu_gfn_to_memslot(vcpu, gfn), gfn);
1989 EXPORT_SYMBOL_GPL(kvm_vcpu_gfn_to_pfn);
1991 int gfn_to_page_many_atomic(struct kvm_memory_slot *slot, gfn_t gfn,
1992 struct page **pages, int nr_pages)
1997 addr = gfn_to_hva_many(slot, gfn, &entry);
1998 if (kvm_is_error_hva(addr))
2001 if (entry < nr_pages)
2004 return get_user_pages_fast_only(addr, nr_pages, FOLL_WRITE, pages);
2006 EXPORT_SYMBOL_GPL(gfn_to_page_many_atomic);
2008 static struct page *kvm_pfn_to_page(kvm_pfn_t pfn)
2010 if (is_error_noslot_pfn(pfn))
2011 return KVM_ERR_PTR_BAD_PAGE;
2013 if (kvm_is_reserved_pfn(pfn)) {
2015 return KVM_ERR_PTR_BAD_PAGE;
2018 return pfn_to_page(pfn);
2021 struct page *gfn_to_page(struct kvm *kvm, gfn_t gfn)
2025 pfn = gfn_to_pfn(kvm, gfn);
2027 return kvm_pfn_to_page(pfn);
2029 EXPORT_SYMBOL_GPL(gfn_to_page);
2031 void kvm_release_pfn(kvm_pfn_t pfn, bool dirty, struct gfn_to_pfn_cache *cache)
2037 cache->pfn = cache->gfn = 0;
2040 kvm_release_pfn_dirty(pfn);
2042 kvm_release_pfn_clean(pfn);
2045 static void kvm_cache_gfn_to_pfn(struct kvm_memory_slot *slot, gfn_t gfn,
2046 struct gfn_to_pfn_cache *cache, u64 gen)
2048 kvm_release_pfn(cache->pfn, cache->dirty, cache);
2050 cache->pfn = gfn_to_pfn_memslot(slot, gfn);
2052 cache->dirty = false;
2053 cache->generation = gen;
2056 static int __kvm_map_gfn(struct kvm_memslots *slots, gfn_t gfn,
2057 struct kvm_host_map *map,
2058 struct gfn_to_pfn_cache *cache,
2063 struct page *page = KVM_UNMAPPED_PAGE;
2064 struct kvm_memory_slot *slot = __gfn_to_memslot(slots, gfn);
2065 u64 gen = slots->generation;
2071 if (!cache->pfn || cache->gfn != gfn ||
2072 cache->generation != gen) {
2075 kvm_cache_gfn_to_pfn(slot, gfn, cache, gen);
2081 pfn = gfn_to_pfn_memslot(slot, gfn);
2083 if (is_error_noslot_pfn(pfn))
2086 if (pfn_valid(pfn)) {
2087 page = pfn_to_page(pfn);
2089 hva = kmap_atomic(page);
2092 #ifdef CONFIG_HAS_IOMEM
2093 } else if (!atomic) {
2094 hva = memremap(pfn_to_hpa(pfn), PAGE_SIZE, MEMREMAP_WB);
2111 int kvm_map_gfn(struct kvm_vcpu *vcpu, gfn_t gfn, struct kvm_host_map *map,
2112 struct gfn_to_pfn_cache *cache, bool atomic)
2114 return __kvm_map_gfn(kvm_memslots(vcpu->kvm), gfn, map,
2117 EXPORT_SYMBOL_GPL(kvm_map_gfn);
2119 int kvm_vcpu_map(struct kvm_vcpu *vcpu, gfn_t gfn, struct kvm_host_map *map)
2121 return __kvm_map_gfn(kvm_vcpu_memslots(vcpu), gfn, map,
2124 EXPORT_SYMBOL_GPL(kvm_vcpu_map);
2126 static void __kvm_unmap_gfn(struct kvm_memory_slot *memslot,
2127 struct kvm_host_map *map,
2128 struct gfn_to_pfn_cache *cache,
2129 bool dirty, bool atomic)
2137 if (map->page != KVM_UNMAPPED_PAGE) {
2139 kunmap_atomic(map->hva);
2143 #ifdef CONFIG_HAS_IOMEM
2147 WARN_ONCE(1, "Unexpected unmapping in atomic context");
2151 mark_page_dirty_in_slot(memslot, map->gfn);
2154 cache->dirty |= dirty;
2156 kvm_release_pfn(map->pfn, dirty, NULL);
2162 int kvm_unmap_gfn(struct kvm_vcpu *vcpu, struct kvm_host_map *map,
2163 struct gfn_to_pfn_cache *cache, bool dirty, bool atomic)
2165 __kvm_unmap_gfn(gfn_to_memslot(vcpu->kvm, map->gfn), map,
2166 cache, dirty, atomic);
2169 EXPORT_SYMBOL_GPL(kvm_unmap_gfn);
2171 void kvm_vcpu_unmap(struct kvm_vcpu *vcpu, struct kvm_host_map *map, bool dirty)
2173 __kvm_unmap_gfn(kvm_vcpu_gfn_to_memslot(vcpu, map->gfn), map, NULL,
2176 EXPORT_SYMBOL_GPL(kvm_vcpu_unmap);
2178 struct page *kvm_vcpu_gfn_to_page(struct kvm_vcpu *vcpu, gfn_t gfn)
2182 pfn = kvm_vcpu_gfn_to_pfn(vcpu, gfn);
2184 return kvm_pfn_to_page(pfn);
2186 EXPORT_SYMBOL_GPL(kvm_vcpu_gfn_to_page);
2188 void kvm_release_page_clean(struct page *page)
2190 WARN_ON(is_error_page(page));
2192 kvm_release_pfn_clean(page_to_pfn(page));
2194 EXPORT_SYMBOL_GPL(kvm_release_page_clean);
2196 void kvm_release_pfn_clean(kvm_pfn_t pfn)
2198 if (!is_error_noslot_pfn(pfn) && !kvm_is_reserved_pfn(pfn))
2199 put_page(pfn_to_page(pfn));
2201 EXPORT_SYMBOL_GPL(kvm_release_pfn_clean);
2203 void kvm_release_page_dirty(struct page *page)
2205 WARN_ON(is_error_page(page));
2207 kvm_release_pfn_dirty(page_to_pfn(page));
2209 EXPORT_SYMBOL_GPL(kvm_release_page_dirty);
2211 void kvm_release_pfn_dirty(kvm_pfn_t pfn)
2213 kvm_set_pfn_dirty(pfn);
2214 kvm_release_pfn_clean(pfn);
2216 EXPORT_SYMBOL_GPL(kvm_release_pfn_dirty);
2218 void kvm_set_pfn_dirty(kvm_pfn_t pfn)
2220 if (!kvm_is_reserved_pfn(pfn) && !kvm_is_zone_device_pfn(pfn))
2221 SetPageDirty(pfn_to_page(pfn));
2223 EXPORT_SYMBOL_GPL(kvm_set_pfn_dirty);
2225 void kvm_set_pfn_accessed(kvm_pfn_t pfn)
2227 if (!kvm_is_reserved_pfn(pfn) && !kvm_is_zone_device_pfn(pfn))
2228 mark_page_accessed(pfn_to_page(pfn));
2230 EXPORT_SYMBOL_GPL(kvm_set_pfn_accessed);
2232 void kvm_get_pfn(kvm_pfn_t pfn)
2234 if (!kvm_is_reserved_pfn(pfn))
2235 get_page(pfn_to_page(pfn));
2237 EXPORT_SYMBOL_GPL(kvm_get_pfn);
2239 static int next_segment(unsigned long len, int offset)
2241 if (len > PAGE_SIZE - offset)
2242 return PAGE_SIZE - offset;
2247 static int __kvm_read_guest_page(struct kvm_memory_slot *slot, gfn_t gfn,
2248 void *data, int offset, int len)
2253 addr = gfn_to_hva_memslot_prot(slot, gfn, NULL);
2254 if (kvm_is_error_hva(addr))
2256 r = __copy_from_user(data, (void __user *)addr + offset, len);
2262 int kvm_read_guest_page(struct kvm *kvm, gfn_t gfn, void *data, int offset,
2265 struct kvm_memory_slot *slot = gfn_to_memslot(kvm, gfn);
2267 return __kvm_read_guest_page(slot, gfn, data, offset, len);
2269 EXPORT_SYMBOL_GPL(kvm_read_guest_page);
2271 int kvm_vcpu_read_guest_page(struct kvm_vcpu *vcpu, gfn_t gfn, void *data,
2272 int offset, int len)
2274 struct kvm_memory_slot *slot = kvm_vcpu_gfn_to_memslot(vcpu, gfn);
2276 return __kvm_read_guest_page(slot, gfn, data, offset, len);
2278 EXPORT_SYMBOL_GPL(kvm_vcpu_read_guest_page);
2280 int kvm_read_guest(struct kvm *kvm, gpa_t gpa, void *data, unsigned long len)
2282 gfn_t gfn = gpa >> PAGE_SHIFT;
2284 int offset = offset_in_page(gpa);
2287 while ((seg = next_segment(len, offset)) != 0) {
2288 ret = kvm_read_guest_page(kvm, gfn, data, offset, seg);
2298 EXPORT_SYMBOL_GPL(kvm_read_guest);
2300 int kvm_vcpu_read_guest(struct kvm_vcpu *vcpu, gpa_t gpa, void *data, unsigned long len)
2302 gfn_t gfn = gpa >> PAGE_SHIFT;
2304 int offset = offset_in_page(gpa);
2307 while ((seg = next_segment(len, offset)) != 0) {
2308 ret = kvm_vcpu_read_guest_page(vcpu, gfn, data, offset, seg);
2318 EXPORT_SYMBOL_GPL(kvm_vcpu_read_guest);
2320 static int __kvm_read_guest_atomic(struct kvm_memory_slot *slot, gfn_t gfn,
2321 void *data, int offset, unsigned long len)
2326 addr = gfn_to_hva_memslot_prot(slot, gfn, NULL);
2327 if (kvm_is_error_hva(addr))
2329 pagefault_disable();
2330 r = __copy_from_user_inatomic(data, (void __user *)addr + offset, len);
2337 int kvm_vcpu_read_guest_atomic(struct kvm_vcpu *vcpu, gpa_t gpa,
2338 void *data, unsigned long len)
2340 gfn_t gfn = gpa >> PAGE_SHIFT;
2341 struct kvm_memory_slot *slot = kvm_vcpu_gfn_to_memslot(vcpu, gfn);
2342 int offset = offset_in_page(gpa);
2344 return __kvm_read_guest_atomic(slot, gfn, data, offset, len);
2346 EXPORT_SYMBOL_GPL(kvm_vcpu_read_guest_atomic);
2348 static int __kvm_write_guest_page(struct kvm_memory_slot *memslot, gfn_t gfn,
2349 const void *data, int offset, int len)
2354 addr = gfn_to_hva_memslot(memslot, gfn);
2355 if (kvm_is_error_hva(addr))
2357 r = __copy_to_user((void __user *)addr + offset, data, len);
2360 mark_page_dirty_in_slot(memslot, gfn);
2364 int kvm_write_guest_page(struct kvm *kvm, gfn_t gfn,
2365 const void *data, int offset, int len)
2367 struct kvm_memory_slot *slot = gfn_to_memslot(kvm, gfn);
2369 return __kvm_write_guest_page(slot, gfn, data, offset, len);
2371 EXPORT_SYMBOL_GPL(kvm_write_guest_page);
2373 int kvm_vcpu_write_guest_page(struct kvm_vcpu *vcpu, gfn_t gfn,
2374 const void *data, int offset, int len)
2376 struct kvm_memory_slot *slot = kvm_vcpu_gfn_to_memslot(vcpu, gfn);
2378 return __kvm_write_guest_page(slot, gfn, data, offset, len);
2380 EXPORT_SYMBOL_GPL(kvm_vcpu_write_guest_page);
2382 int kvm_write_guest(struct kvm *kvm, gpa_t gpa, const void *data,
2385 gfn_t gfn = gpa >> PAGE_SHIFT;
2387 int offset = offset_in_page(gpa);
2390 while ((seg = next_segment(len, offset)) != 0) {
2391 ret = kvm_write_guest_page(kvm, gfn, data, offset, seg);
2401 EXPORT_SYMBOL_GPL(kvm_write_guest);
2403 int kvm_vcpu_write_guest(struct kvm_vcpu *vcpu, gpa_t gpa, const void *data,
2406 gfn_t gfn = gpa >> PAGE_SHIFT;
2408 int offset = offset_in_page(gpa);
2411 while ((seg = next_segment(len, offset)) != 0) {
2412 ret = kvm_vcpu_write_guest_page(vcpu, gfn, data, offset, seg);
2422 EXPORT_SYMBOL_GPL(kvm_vcpu_write_guest);
2424 static int __kvm_gfn_to_hva_cache_init(struct kvm_memslots *slots,
2425 struct gfn_to_hva_cache *ghc,
2426 gpa_t gpa, unsigned long len)
2428 int offset = offset_in_page(gpa);
2429 gfn_t start_gfn = gpa >> PAGE_SHIFT;
2430 gfn_t end_gfn = (gpa + len - 1) >> PAGE_SHIFT;
2431 gfn_t nr_pages_needed = end_gfn - start_gfn + 1;
2432 gfn_t nr_pages_avail;
2434 /* Update ghc->generation before performing any error checks. */
2435 ghc->generation = slots->generation;
2437 if (start_gfn > end_gfn) {
2438 ghc->hva = KVM_HVA_ERR_BAD;
2443 * If the requested region crosses two memslots, we still
2444 * verify that the entire region is valid here.
2446 for ( ; start_gfn <= end_gfn; start_gfn += nr_pages_avail) {
2447 ghc->memslot = __gfn_to_memslot(slots, start_gfn);
2448 ghc->hva = gfn_to_hva_many(ghc->memslot, start_gfn,
2450 if (kvm_is_error_hva(ghc->hva))
2454 /* Use the slow path for cross page reads and writes. */
2455 if (nr_pages_needed == 1)
2458 ghc->memslot = NULL;
2465 int kvm_gfn_to_hva_cache_init(struct kvm *kvm, struct gfn_to_hva_cache *ghc,
2466 gpa_t gpa, unsigned long len)
2468 struct kvm_memslots *slots = kvm_memslots(kvm);
2469 return __kvm_gfn_to_hva_cache_init(slots, ghc, gpa, len);
2471 EXPORT_SYMBOL_GPL(kvm_gfn_to_hva_cache_init);
2473 int kvm_write_guest_offset_cached(struct kvm *kvm, struct gfn_to_hva_cache *ghc,
2474 void *data, unsigned int offset,
2477 struct kvm_memslots *slots = kvm_memslots(kvm);
2479 gpa_t gpa = ghc->gpa + offset;
2481 BUG_ON(len + offset > ghc->len);
2483 if (slots->generation != ghc->generation) {
2484 if (__kvm_gfn_to_hva_cache_init(slots, ghc, ghc->gpa, ghc->len))
2488 if (kvm_is_error_hva(ghc->hva))
2491 if (unlikely(!ghc->memslot))
2492 return kvm_write_guest(kvm, gpa, data, len);
2494 r = __copy_to_user((void __user *)ghc->hva + offset, data, len);
2497 mark_page_dirty_in_slot(ghc->memslot, gpa >> PAGE_SHIFT);
2501 EXPORT_SYMBOL_GPL(kvm_write_guest_offset_cached);
2503 int kvm_write_guest_cached(struct kvm *kvm, struct gfn_to_hva_cache *ghc,
2504 void *data, unsigned long len)
2506 return kvm_write_guest_offset_cached(kvm, ghc, data, 0, len);
2508 EXPORT_SYMBOL_GPL(kvm_write_guest_cached);
2510 int kvm_read_guest_offset_cached(struct kvm *kvm, struct gfn_to_hva_cache *ghc,
2511 void *data, unsigned int offset,
2514 struct kvm_memslots *slots = kvm_memslots(kvm);
2516 gpa_t gpa = ghc->gpa + offset;
2518 BUG_ON(len + offset > ghc->len);
2520 if (slots->generation != ghc->generation) {
2521 if (__kvm_gfn_to_hva_cache_init(slots, ghc, ghc->gpa, ghc->len))
2525 if (kvm_is_error_hva(ghc->hva))
2528 if (unlikely(!ghc->memslot))
2529 return kvm_read_guest(kvm, gpa, data, len);
2531 r = __copy_from_user(data, (void __user *)ghc->hva + offset, len);
2537 EXPORT_SYMBOL_GPL(kvm_read_guest_offset_cached);
2539 int kvm_read_guest_cached(struct kvm *kvm, struct gfn_to_hva_cache *ghc,
2540 void *data, unsigned long len)
2542 return kvm_read_guest_offset_cached(kvm, ghc, data, 0, len);
2544 EXPORT_SYMBOL_GPL(kvm_read_guest_cached);
2546 int kvm_clear_guest_page(struct kvm *kvm, gfn_t gfn, int offset, int len)
2548 const void *zero_page = (const void *) __va(page_to_phys(ZERO_PAGE(0)));
2550 return kvm_write_guest_page(kvm, gfn, zero_page, offset, len);
2552 EXPORT_SYMBOL_GPL(kvm_clear_guest_page);
2554 int kvm_clear_guest(struct kvm *kvm, gpa_t gpa, unsigned long len)
2556 gfn_t gfn = gpa >> PAGE_SHIFT;
2558 int offset = offset_in_page(gpa);
2561 while ((seg = next_segment(len, offset)) != 0) {
2562 ret = kvm_clear_guest_page(kvm, gfn, offset, seg);
2571 EXPORT_SYMBOL_GPL(kvm_clear_guest);
2573 static void mark_page_dirty_in_slot(struct kvm_memory_slot *memslot,
2576 if (memslot && memslot->dirty_bitmap) {
2577 unsigned long rel_gfn = gfn - memslot->base_gfn;
2579 set_bit_le(rel_gfn, memslot->dirty_bitmap);
2583 void mark_page_dirty(struct kvm *kvm, gfn_t gfn)
2585 struct kvm_memory_slot *memslot;
2587 memslot = gfn_to_memslot(kvm, gfn);
2588 mark_page_dirty_in_slot(memslot, gfn);
2590 EXPORT_SYMBOL_GPL(mark_page_dirty);
2592 void kvm_vcpu_mark_page_dirty(struct kvm_vcpu *vcpu, gfn_t gfn)
2594 struct kvm_memory_slot *memslot;
2596 memslot = kvm_vcpu_gfn_to_memslot(vcpu, gfn);
2597 mark_page_dirty_in_slot(memslot, gfn);
2599 EXPORT_SYMBOL_GPL(kvm_vcpu_mark_page_dirty);
2601 void kvm_sigset_activate(struct kvm_vcpu *vcpu)
2603 if (!vcpu->sigset_active)
2607 * This does a lockless modification of ->real_blocked, which is fine
2608 * because, only current can change ->real_blocked and all readers of
2609 * ->real_blocked don't care as long ->real_blocked is always a subset
2612 sigprocmask(SIG_SETMASK, &vcpu->sigset, ¤t->real_blocked);
2615 void kvm_sigset_deactivate(struct kvm_vcpu *vcpu)
2617 if (!vcpu->sigset_active)
2620 sigprocmask(SIG_SETMASK, ¤t->real_blocked, NULL);
2621 sigemptyset(¤t->real_blocked);
2624 static void grow_halt_poll_ns(struct kvm_vcpu *vcpu)
2626 unsigned int old, val, grow, grow_start;
2628 old = val = vcpu->halt_poll_ns;
2629 grow_start = READ_ONCE(halt_poll_ns_grow_start);
2630 grow = READ_ONCE(halt_poll_ns_grow);
2635 if (val < grow_start)
2638 if (val > halt_poll_ns)
2641 vcpu->halt_poll_ns = val;
2643 trace_kvm_halt_poll_ns_grow(vcpu->vcpu_id, val, old);
2646 static void shrink_halt_poll_ns(struct kvm_vcpu *vcpu)
2648 unsigned int old, val, shrink;
2650 old = val = vcpu->halt_poll_ns;
2651 shrink = READ_ONCE(halt_poll_ns_shrink);
2657 vcpu->halt_poll_ns = val;
2658 trace_kvm_halt_poll_ns_shrink(vcpu->vcpu_id, val, old);
2661 static int kvm_vcpu_check_block(struct kvm_vcpu *vcpu)
2664 int idx = srcu_read_lock(&vcpu->kvm->srcu);
2666 if (kvm_arch_vcpu_runnable(vcpu)) {
2667 kvm_make_request(KVM_REQ_UNHALT, vcpu);
2670 if (kvm_cpu_has_pending_timer(vcpu))
2672 if (signal_pending(current))
2677 srcu_read_unlock(&vcpu->kvm->srcu, idx);
2682 update_halt_poll_stats(struct kvm_vcpu *vcpu, u64 poll_ns, bool waited)
2685 vcpu->stat.halt_poll_fail_ns += poll_ns;
2687 vcpu->stat.halt_poll_success_ns += poll_ns;
2691 * The vCPU has executed a HLT instruction with in-kernel mode enabled.
2693 void kvm_vcpu_block(struct kvm_vcpu *vcpu)
2695 ktime_t start, cur, poll_end;
2696 bool waited = false;
2699 kvm_arch_vcpu_blocking(vcpu);
2701 start = cur = poll_end = ktime_get();
2702 if (vcpu->halt_poll_ns && !kvm_arch_no_poll(vcpu)) {
2703 ktime_t stop = ktime_add_ns(ktime_get(), vcpu->halt_poll_ns);
2705 ++vcpu->stat.halt_attempted_poll;
2708 * This sets KVM_REQ_UNHALT if an interrupt
2711 if (kvm_vcpu_check_block(vcpu) < 0) {
2712 ++vcpu->stat.halt_successful_poll;
2713 if (!vcpu_valid_wakeup(vcpu))
2714 ++vcpu->stat.halt_poll_invalid;
2717 poll_end = cur = ktime_get();
2718 } while (single_task_running() && ktime_before(cur, stop));
2721 prepare_to_rcuwait(&vcpu->wait);
2723 set_current_state(TASK_INTERRUPTIBLE);
2725 if (kvm_vcpu_check_block(vcpu) < 0)
2731 finish_rcuwait(&vcpu->wait);
2734 kvm_arch_vcpu_unblocking(vcpu);
2735 block_ns = ktime_to_ns(cur) - ktime_to_ns(start);
2737 update_halt_poll_stats(
2738 vcpu, ktime_to_ns(ktime_sub(poll_end, start)), waited);
2740 if (!kvm_arch_no_poll(vcpu)) {
2741 if (!vcpu_valid_wakeup(vcpu)) {
2742 shrink_halt_poll_ns(vcpu);
2743 } else if (vcpu->kvm->max_halt_poll_ns) {
2744 if (block_ns <= vcpu->halt_poll_ns)
2746 /* we had a long block, shrink polling */
2747 else if (vcpu->halt_poll_ns &&
2748 block_ns > vcpu->kvm->max_halt_poll_ns)
2749 shrink_halt_poll_ns(vcpu);
2750 /* we had a short halt and our poll time is too small */
2751 else if (vcpu->halt_poll_ns < vcpu->kvm->max_halt_poll_ns &&
2752 block_ns < vcpu->kvm->max_halt_poll_ns)
2753 grow_halt_poll_ns(vcpu);
2755 vcpu->halt_poll_ns = 0;
2759 trace_kvm_vcpu_wakeup(block_ns, waited, vcpu_valid_wakeup(vcpu));
2760 kvm_arch_vcpu_block_finish(vcpu);
2762 EXPORT_SYMBOL_GPL(kvm_vcpu_block);
2764 bool kvm_vcpu_wake_up(struct kvm_vcpu *vcpu)
2766 struct rcuwait *waitp;
2768 waitp = kvm_arch_vcpu_get_wait(vcpu);
2769 if (rcuwait_wake_up(waitp)) {
2770 WRITE_ONCE(vcpu->ready, true);
2771 ++vcpu->stat.halt_wakeup;
2777 EXPORT_SYMBOL_GPL(kvm_vcpu_wake_up);
2781 * Kick a sleeping VCPU, or a guest VCPU in guest mode, into host kernel mode.
2783 void kvm_vcpu_kick(struct kvm_vcpu *vcpu)
2786 int cpu = vcpu->cpu;
2788 if (kvm_vcpu_wake_up(vcpu))
2792 if (cpu != me && (unsigned)cpu < nr_cpu_ids && cpu_online(cpu))
2793 if (kvm_arch_vcpu_should_kick(vcpu))
2794 smp_send_reschedule(cpu);
2797 EXPORT_SYMBOL_GPL(kvm_vcpu_kick);
2798 #endif /* !CONFIG_S390 */
2800 int kvm_vcpu_yield_to(struct kvm_vcpu *target)
2803 struct task_struct *task = NULL;
2807 pid = rcu_dereference(target->pid);
2809 task = get_pid_task(pid, PIDTYPE_PID);
2813 ret = yield_to(task, 1);
2814 put_task_struct(task);
2818 EXPORT_SYMBOL_GPL(kvm_vcpu_yield_to);
2821 * Helper that checks whether a VCPU is eligible for directed yield.
2822 * Most eligible candidate to yield is decided by following heuristics:
2824 * (a) VCPU which has not done pl-exit or cpu relax intercepted recently
2825 * (preempted lock holder), indicated by @in_spin_loop.
2826 * Set at the beginning and cleared at the end of interception/PLE handler.
2828 * (b) VCPU which has done pl-exit/ cpu relax intercepted but did not get
2829 * chance last time (mostly it has become eligible now since we have probably
2830 * yielded to lockholder in last iteration. This is done by toggling
2831 * @dy_eligible each time a VCPU checked for eligibility.)
2833 * Yielding to a recently pl-exited/cpu relax intercepted VCPU before yielding
2834 * to preempted lock-holder could result in wrong VCPU selection and CPU
2835 * burning. Giving priority for a potential lock-holder increases lock
2838 * Since algorithm is based on heuristics, accessing another VCPU data without
2839 * locking does not harm. It may result in trying to yield to same VCPU, fail
2840 * and continue with next VCPU and so on.
2842 static bool kvm_vcpu_eligible_for_directed_yield(struct kvm_vcpu *vcpu)
2844 #ifdef CONFIG_HAVE_KVM_CPU_RELAX_INTERCEPT
2847 eligible = !vcpu->spin_loop.in_spin_loop ||
2848 vcpu->spin_loop.dy_eligible;
2850 if (vcpu->spin_loop.in_spin_loop)
2851 kvm_vcpu_set_dy_eligible(vcpu, !vcpu->spin_loop.dy_eligible);
2860 * Unlike kvm_arch_vcpu_runnable, this function is called outside
2861 * a vcpu_load/vcpu_put pair. However, for most architectures
2862 * kvm_arch_vcpu_runnable does not require vcpu_load.
2864 bool __weak kvm_arch_dy_runnable(struct kvm_vcpu *vcpu)
2866 return kvm_arch_vcpu_runnable(vcpu);
2869 static bool vcpu_dy_runnable(struct kvm_vcpu *vcpu)
2871 if (kvm_arch_dy_runnable(vcpu))
2874 #ifdef CONFIG_KVM_ASYNC_PF
2875 if (!list_empty_careful(&vcpu->async_pf.done))
2882 void kvm_vcpu_on_spin(struct kvm_vcpu *me, bool yield_to_kernel_mode)
2884 struct kvm *kvm = me->kvm;
2885 struct kvm_vcpu *vcpu;
2886 int last_boosted_vcpu = me->kvm->last_boosted_vcpu;
2892 kvm_vcpu_set_in_spin_loop(me, true);
2894 * We boost the priority of a VCPU that is runnable but not
2895 * currently running, because it got preempted by something
2896 * else and called schedule in __vcpu_run. Hopefully that
2897 * VCPU is holding the lock that we need and will release it.
2898 * We approximate round-robin by starting at the last boosted VCPU.
2900 for (pass = 0; pass < 2 && !yielded && try; pass++) {
2901 kvm_for_each_vcpu(i, vcpu, kvm) {
2902 if (!pass && i <= last_boosted_vcpu) {
2903 i = last_boosted_vcpu;
2905 } else if (pass && i > last_boosted_vcpu)
2907 if (!READ_ONCE(vcpu->ready))
2911 if (rcuwait_active(&vcpu->wait) &&
2912 !vcpu_dy_runnable(vcpu))
2914 if (READ_ONCE(vcpu->preempted) && yield_to_kernel_mode &&
2915 !kvm_arch_vcpu_in_kernel(vcpu))
2917 if (!kvm_vcpu_eligible_for_directed_yield(vcpu))
2920 yielded = kvm_vcpu_yield_to(vcpu);
2922 kvm->last_boosted_vcpu = i;
2924 } else if (yielded < 0) {
2931 kvm_vcpu_set_in_spin_loop(me, false);
2933 /* Ensure vcpu is not eligible during next spinloop */
2934 kvm_vcpu_set_dy_eligible(me, false);
2936 EXPORT_SYMBOL_GPL(kvm_vcpu_on_spin);
2938 static vm_fault_t kvm_vcpu_fault(struct vm_fault *vmf)
2940 struct kvm_vcpu *vcpu = vmf->vma->vm_file->private_data;
2943 if (vmf->pgoff == 0)
2944 page = virt_to_page(vcpu->run);
2946 else if (vmf->pgoff == KVM_PIO_PAGE_OFFSET)
2947 page = virt_to_page(vcpu->arch.pio_data);
2949 #ifdef CONFIG_KVM_MMIO
2950 else if (vmf->pgoff == KVM_COALESCED_MMIO_PAGE_OFFSET)
2951 page = virt_to_page(vcpu->kvm->coalesced_mmio_ring);
2954 return kvm_arch_vcpu_fault(vcpu, vmf);
2960 static const struct vm_operations_struct kvm_vcpu_vm_ops = {
2961 .fault = kvm_vcpu_fault,
2964 static int kvm_vcpu_mmap(struct file *file, struct vm_area_struct *vma)
2966 vma->vm_ops = &kvm_vcpu_vm_ops;
2970 static int kvm_vcpu_release(struct inode *inode, struct file *filp)
2972 struct kvm_vcpu *vcpu = filp->private_data;
2974 debugfs_remove_recursive(vcpu->debugfs_dentry);
2975 kvm_put_kvm(vcpu->kvm);
2979 static struct file_operations kvm_vcpu_fops = {
2980 .release = kvm_vcpu_release,
2981 .unlocked_ioctl = kvm_vcpu_ioctl,
2982 .mmap = kvm_vcpu_mmap,
2983 .llseek = noop_llseek,
2984 KVM_COMPAT(kvm_vcpu_compat_ioctl),
2988 * Allocates an inode for the vcpu.
2990 static int create_vcpu_fd(struct kvm_vcpu *vcpu)
2992 char name[8 + 1 + ITOA_MAX_LEN + 1];
2994 snprintf(name, sizeof(name), "kvm-vcpu:%d", vcpu->vcpu_id);
2995 return anon_inode_getfd(name, &kvm_vcpu_fops, vcpu, O_RDWR | O_CLOEXEC);
2998 static void kvm_create_vcpu_debugfs(struct kvm_vcpu *vcpu)
3000 #ifdef __KVM_HAVE_ARCH_VCPU_DEBUGFS
3001 char dir_name[ITOA_MAX_LEN * 2];
3003 if (!debugfs_initialized())
3006 snprintf(dir_name, sizeof(dir_name), "vcpu%d", vcpu->vcpu_id);
3007 vcpu->debugfs_dentry = debugfs_create_dir(dir_name,
3008 vcpu->kvm->debugfs_dentry);
3010 kvm_arch_create_vcpu_debugfs(vcpu);
3015 * Creates some virtual cpus. Good luck creating more than one.
3017 static int kvm_vm_ioctl_create_vcpu(struct kvm *kvm, u32 id)
3020 struct kvm_vcpu *vcpu;
3023 if (id >= KVM_MAX_VCPU_ID)
3026 mutex_lock(&kvm->lock);
3027 if (kvm->created_vcpus == KVM_MAX_VCPUS) {
3028 mutex_unlock(&kvm->lock);
3032 kvm->created_vcpus++;
3033 mutex_unlock(&kvm->lock);
3035 r = kvm_arch_vcpu_precreate(kvm, id);
3037 goto vcpu_decrement;
3039 vcpu = kmem_cache_zalloc(kvm_vcpu_cache, GFP_KERNEL);
3042 goto vcpu_decrement;
3045 BUILD_BUG_ON(sizeof(struct kvm_run) > PAGE_SIZE);
3046 page = alloc_page(GFP_KERNEL | __GFP_ZERO);
3051 vcpu->run = page_address(page);
3053 kvm_vcpu_init(vcpu, kvm, id);
3055 r = kvm_arch_vcpu_create(vcpu);
3057 goto vcpu_free_run_page;
3059 mutex_lock(&kvm->lock);
3060 if (kvm_get_vcpu_by_id(kvm, id)) {
3062 goto unlock_vcpu_destroy;
3065 vcpu->vcpu_idx = atomic_read(&kvm->online_vcpus);
3066 BUG_ON(kvm->vcpus[vcpu->vcpu_idx]);
3068 /* Now it's all set up, let userspace reach it */
3070 r = create_vcpu_fd(vcpu);
3072 kvm_put_kvm_no_destroy(kvm);
3073 goto unlock_vcpu_destroy;
3076 kvm->vcpus[vcpu->vcpu_idx] = vcpu;
3079 * Pairs with smp_rmb() in kvm_get_vcpu. Write kvm->vcpus
3080 * before kvm->online_vcpu's incremented value.
3083 atomic_inc(&kvm->online_vcpus);
3085 mutex_unlock(&kvm->lock);
3086 kvm_arch_vcpu_postcreate(vcpu);
3087 kvm_create_vcpu_debugfs(vcpu);
3090 unlock_vcpu_destroy:
3091 mutex_unlock(&kvm->lock);
3092 kvm_arch_vcpu_destroy(vcpu);
3094 free_page((unsigned long)vcpu->run);
3096 kmem_cache_free(kvm_vcpu_cache, vcpu);
3098 mutex_lock(&kvm->lock);
3099 kvm->created_vcpus--;
3100 mutex_unlock(&kvm->lock);
3104 static int kvm_vcpu_ioctl_set_sigmask(struct kvm_vcpu *vcpu, sigset_t *sigset)
3107 sigdelsetmask(sigset, sigmask(SIGKILL)|sigmask(SIGSTOP));
3108 vcpu->sigset_active = 1;
3109 vcpu->sigset = *sigset;
3111 vcpu->sigset_active = 0;
3115 static long kvm_vcpu_ioctl(struct file *filp,
3116 unsigned int ioctl, unsigned long arg)
3118 struct kvm_vcpu *vcpu = filp->private_data;
3119 void __user *argp = (void __user *)arg;
3121 struct kvm_fpu *fpu = NULL;
3122 struct kvm_sregs *kvm_sregs = NULL;
3124 if (vcpu->kvm->mm != current->mm)
3127 if (unlikely(_IOC_TYPE(ioctl) != KVMIO))
3131 * Some architectures have vcpu ioctls that are asynchronous to vcpu
3132 * execution; mutex_lock() would break them.
3134 r = kvm_arch_vcpu_async_ioctl(filp, ioctl, arg);
3135 if (r != -ENOIOCTLCMD)
3138 if (mutex_lock_killable(&vcpu->mutex))
3146 oldpid = rcu_access_pointer(vcpu->pid);
3147 if (unlikely(oldpid != task_pid(current))) {
3148 /* The thread running this VCPU changed. */
3151 r = kvm_arch_vcpu_run_pid_change(vcpu);
3155 newpid = get_task_pid(current, PIDTYPE_PID);
3156 rcu_assign_pointer(vcpu->pid, newpid);
3161 r = kvm_arch_vcpu_ioctl_run(vcpu);
3162 trace_kvm_userspace_exit(vcpu->run->exit_reason, r);
3165 case KVM_GET_REGS: {
3166 struct kvm_regs *kvm_regs;
3169 kvm_regs = kzalloc(sizeof(struct kvm_regs), GFP_KERNEL_ACCOUNT);
3172 r = kvm_arch_vcpu_ioctl_get_regs(vcpu, kvm_regs);
3176 if (copy_to_user(argp, kvm_regs, sizeof(struct kvm_regs)))
3183 case KVM_SET_REGS: {
3184 struct kvm_regs *kvm_regs;
3186 kvm_regs = memdup_user(argp, sizeof(*kvm_regs));
3187 if (IS_ERR(kvm_regs)) {
3188 r = PTR_ERR(kvm_regs);
3191 r = kvm_arch_vcpu_ioctl_set_regs(vcpu, kvm_regs);
3195 case KVM_GET_SREGS: {
3196 kvm_sregs = kzalloc(sizeof(struct kvm_sregs),
3197 GFP_KERNEL_ACCOUNT);
3201 r = kvm_arch_vcpu_ioctl_get_sregs(vcpu, kvm_sregs);
3205 if (copy_to_user(argp, kvm_sregs, sizeof(struct kvm_sregs)))
3210 case KVM_SET_SREGS: {
3211 kvm_sregs = memdup_user(argp, sizeof(*kvm_sregs));
3212 if (IS_ERR(kvm_sregs)) {
3213 r = PTR_ERR(kvm_sregs);
3217 r = kvm_arch_vcpu_ioctl_set_sregs(vcpu, kvm_sregs);
3220 case KVM_GET_MP_STATE: {
3221 struct kvm_mp_state mp_state;
3223 r = kvm_arch_vcpu_ioctl_get_mpstate(vcpu, &mp_state);
3227 if (copy_to_user(argp, &mp_state, sizeof(mp_state)))
3232 case KVM_SET_MP_STATE: {
3233 struct kvm_mp_state mp_state;
3236 if (copy_from_user(&mp_state, argp, sizeof(mp_state)))
3238 r = kvm_arch_vcpu_ioctl_set_mpstate(vcpu, &mp_state);
3241 case KVM_TRANSLATE: {
3242 struct kvm_translation tr;
3245 if (copy_from_user(&tr, argp, sizeof(tr)))
3247 r = kvm_arch_vcpu_ioctl_translate(vcpu, &tr);
3251 if (copy_to_user(argp, &tr, sizeof(tr)))
3256 case KVM_SET_GUEST_DEBUG: {
3257 struct kvm_guest_debug dbg;
3260 if (copy_from_user(&dbg, argp, sizeof(dbg)))
3262 r = kvm_arch_vcpu_ioctl_set_guest_debug(vcpu, &dbg);
3265 case KVM_SET_SIGNAL_MASK: {
3266 struct kvm_signal_mask __user *sigmask_arg = argp;
3267 struct kvm_signal_mask kvm_sigmask;
3268 sigset_t sigset, *p;
3273 if (copy_from_user(&kvm_sigmask, argp,
3274 sizeof(kvm_sigmask)))
3277 if (kvm_sigmask.len != sizeof(sigset))
3280 if (copy_from_user(&sigset, sigmask_arg->sigset,
3285 r = kvm_vcpu_ioctl_set_sigmask(vcpu, p);
3289 fpu = kzalloc(sizeof(struct kvm_fpu), GFP_KERNEL_ACCOUNT);
3293 r = kvm_arch_vcpu_ioctl_get_fpu(vcpu, fpu);
3297 if (copy_to_user(argp, fpu, sizeof(struct kvm_fpu)))
3303 fpu = memdup_user(argp, sizeof(*fpu));
3309 r = kvm_arch_vcpu_ioctl_set_fpu(vcpu, fpu);
3313 r = kvm_arch_vcpu_ioctl(filp, ioctl, arg);
3316 mutex_unlock(&vcpu->mutex);
3322 #ifdef CONFIG_KVM_COMPAT
3323 static long kvm_vcpu_compat_ioctl(struct file *filp,
3324 unsigned int ioctl, unsigned long arg)
3326 struct kvm_vcpu *vcpu = filp->private_data;
3327 void __user *argp = compat_ptr(arg);
3330 if (vcpu->kvm->mm != current->mm)
3334 case KVM_SET_SIGNAL_MASK: {
3335 struct kvm_signal_mask __user *sigmask_arg = argp;
3336 struct kvm_signal_mask kvm_sigmask;
3341 if (copy_from_user(&kvm_sigmask, argp,
3342 sizeof(kvm_sigmask)))
3345 if (kvm_sigmask.len != sizeof(compat_sigset_t))
3348 if (get_compat_sigset(&sigset, (void *)sigmask_arg->sigset))
3350 r = kvm_vcpu_ioctl_set_sigmask(vcpu, &sigset);
3352 r = kvm_vcpu_ioctl_set_sigmask(vcpu, NULL);
3356 r = kvm_vcpu_ioctl(filp, ioctl, arg);
3364 static int kvm_device_mmap(struct file *filp, struct vm_area_struct *vma)
3366 struct kvm_device *dev = filp->private_data;
3369 return dev->ops->mmap(dev, vma);
3374 static int kvm_device_ioctl_attr(struct kvm_device *dev,
3375 int (*accessor)(struct kvm_device *dev,
3376 struct kvm_device_attr *attr),
3379 struct kvm_device_attr attr;
3384 if (copy_from_user(&attr, (void __user *)arg, sizeof(attr)))
3387 return accessor(dev, &attr);
3390 static long kvm_device_ioctl(struct file *filp, unsigned int ioctl,
3393 struct kvm_device *dev = filp->private_data;
3395 if (dev->kvm->mm != current->mm)
3399 case KVM_SET_DEVICE_ATTR:
3400 return kvm_device_ioctl_attr(dev, dev->ops->set_attr, arg);
3401 case KVM_GET_DEVICE_ATTR:
3402 return kvm_device_ioctl_attr(dev, dev->ops->get_attr, arg);
3403 case KVM_HAS_DEVICE_ATTR:
3404 return kvm_device_ioctl_attr(dev, dev->ops->has_attr, arg);
3406 if (dev->ops->ioctl)
3407 return dev->ops->ioctl(dev, ioctl, arg);
3413 static int kvm_device_release(struct inode *inode, struct file *filp)
3415 struct kvm_device *dev = filp->private_data;
3416 struct kvm *kvm = dev->kvm;
3418 if (dev->ops->release) {
3419 mutex_lock(&kvm->lock);
3420 list_del(&dev->vm_node);
3421 dev->ops->release(dev);
3422 mutex_unlock(&kvm->lock);
3429 static const struct file_operations kvm_device_fops = {
3430 .unlocked_ioctl = kvm_device_ioctl,
3431 .release = kvm_device_release,
3432 KVM_COMPAT(kvm_device_ioctl),
3433 .mmap = kvm_device_mmap,
3436 struct kvm_device *kvm_device_from_filp(struct file *filp)
3438 if (filp->f_op != &kvm_device_fops)
3441 return filp->private_data;
3444 static const struct kvm_device_ops *kvm_device_ops_table[KVM_DEV_TYPE_MAX] = {
3445 #ifdef CONFIG_KVM_MPIC
3446 [KVM_DEV_TYPE_FSL_MPIC_20] = &kvm_mpic_ops,
3447 [KVM_DEV_TYPE_FSL_MPIC_42] = &kvm_mpic_ops,
3451 int kvm_register_device_ops(const struct kvm_device_ops *ops, u32 type)
3453 if (type >= ARRAY_SIZE(kvm_device_ops_table))
3456 if (kvm_device_ops_table[type] != NULL)
3459 kvm_device_ops_table[type] = ops;
3463 void kvm_unregister_device_ops(u32 type)
3465 if (kvm_device_ops_table[type] != NULL)
3466 kvm_device_ops_table[type] = NULL;
3469 static int kvm_ioctl_create_device(struct kvm *kvm,
3470 struct kvm_create_device *cd)
3472 const struct kvm_device_ops *ops = NULL;
3473 struct kvm_device *dev;
3474 bool test = cd->flags & KVM_CREATE_DEVICE_TEST;
3478 if (cd->type >= ARRAY_SIZE(kvm_device_ops_table))
3481 type = array_index_nospec(cd->type, ARRAY_SIZE(kvm_device_ops_table));
3482 ops = kvm_device_ops_table[type];
3489 dev = kzalloc(sizeof(*dev), GFP_KERNEL_ACCOUNT);
3496 mutex_lock(&kvm->lock);
3497 ret = ops->create(dev, type);
3499 mutex_unlock(&kvm->lock);
3503 list_add(&dev->vm_node, &kvm->devices);
3504 mutex_unlock(&kvm->lock);
3510 ret = anon_inode_getfd(ops->name, &kvm_device_fops, dev, O_RDWR | O_CLOEXEC);
3512 kvm_put_kvm_no_destroy(kvm);
3513 mutex_lock(&kvm->lock);
3514 list_del(&dev->vm_node);
3515 mutex_unlock(&kvm->lock);
3524 static long kvm_vm_ioctl_check_extension_generic(struct kvm *kvm, long arg)
3527 case KVM_CAP_USER_MEMORY:
3528 case KVM_CAP_DESTROY_MEMORY_REGION_WORKS:
3529 case KVM_CAP_JOIN_MEMORY_REGIONS_WORKS:
3530 case KVM_CAP_INTERNAL_ERROR_DATA:
3531 #ifdef CONFIG_HAVE_KVM_MSI
3532 case KVM_CAP_SIGNAL_MSI:
3534 #ifdef CONFIG_HAVE_KVM_IRQFD
3536 case KVM_CAP_IRQFD_RESAMPLE:
3538 case KVM_CAP_IOEVENTFD_ANY_LENGTH:
3539 case KVM_CAP_CHECK_EXTENSION_VM:
3540 case KVM_CAP_ENABLE_CAP_VM:
3541 case KVM_CAP_HALT_POLL:
3543 #ifdef CONFIG_KVM_MMIO
3544 case KVM_CAP_COALESCED_MMIO:
3545 return KVM_COALESCED_MMIO_PAGE_OFFSET;
3546 case KVM_CAP_COALESCED_PIO:
3549 #ifdef CONFIG_KVM_GENERIC_DIRTYLOG_READ_PROTECT
3550 case KVM_CAP_MANUAL_DIRTY_LOG_PROTECT2:
3551 return KVM_DIRTY_LOG_MANUAL_CAPS;
3553 #ifdef CONFIG_HAVE_KVM_IRQ_ROUTING
3554 case KVM_CAP_IRQ_ROUTING:
3555 return KVM_MAX_IRQ_ROUTES;
3557 #if KVM_ADDRESS_SPACE_NUM > 1
3558 case KVM_CAP_MULTI_ADDRESS_SPACE:
3559 return KVM_ADDRESS_SPACE_NUM;
3561 case KVM_CAP_NR_MEMSLOTS:
3562 return KVM_USER_MEM_SLOTS;
3566 return kvm_vm_ioctl_check_extension(kvm, arg);
3569 int __attribute__((weak)) kvm_vm_ioctl_enable_cap(struct kvm *kvm,
3570 struct kvm_enable_cap *cap)
3575 static int kvm_vm_ioctl_enable_cap_generic(struct kvm *kvm,
3576 struct kvm_enable_cap *cap)
3579 #ifdef CONFIG_KVM_GENERIC_DIRTYLOG_READ_PROTECT
3580 case KVM_CAP_MANUAL_DIRTY_LOG_PROTECT2: {
3581 u64 allowed_options = KVM_DIRTY_LOG_MANUAL_PROTECT_ENABLE;
3583 if (cap->args[0] & KVM_DIRTY_LOG_MANUAL_PROTECT_ENABLE)
3584 allowed_options = KVM_DIRTY_LOG_MANUAL_CAPS;
3586 if (cap->flags || (cap->args[0] & ~allowed_options))
3588 kvm->manual_dirty_log_protect = cap->args[0];
3592 case KVM_CAP_HALT_POLL: {
3593 if (cap->flags || cap->args[0] != (unsigned int)cap->args[0])
3596 kvm->max_halt_poll_ns = cap->args[0];
3600 return kvm_vm_ioctl_enable_cap(kvm, cap);
3604 static long kvm_vm_ioctl(struct file *filp,
3605 unsigned int ioctl, unsigned long arg)
3607 struct kvm *kvm = filp->private_data;
3608 void __user *argp = (void __user *)arg;
3611 if (kvm->mm != current->mm)
3614 case KVM_CREATE_VCPU:
3615 r = kvm_vm_ioctl_create_vcpu(kvm, arg);
3617 case KVM_ENABLE_CAP: {
3618 struct kvm_enable_cap cap;
3621 if (copy_from_user(&cap, argp, sizeof(cap)))
3623 r = kvm_vm_ioctl_enable_cap_generic(kvm, &cap);
3626 case KVM_SET_USER_MEMORY_REGION: {
3627 struct kvm_userspace_memory_region kvm_userspace_mem;
3630 if (copy_from_user(&kvm_userspace_mem, argp,
3631 sizeof(kvm_userspace_mem)))
3634 r = kvm_vm_ioctl_set_memory_region(kvm, &kvm_userspace_mem);
3637 case KVM_GET_DIRTY_LOG: {
3638 struct kvm_dirty_log log;
3641 if (copy_from_user(&log, argp, sizeof(log)))
3643 r = kvm_vm_ioctl_get_dirty_log(kvm, &log);
3646 #ifdef CONFIG_KVM_GENERIC_DIRTYLOG_READ_PROTECT
3647 case KVM_CLEAR_DIRTY_LOG: {
3648 struct kvm_clear_dirty_log log;
3651 if (copy_from_user(&log, argp, sizeof(log)))
3653 r = kvm_vm_ioctl_clear_dirty_log(kvm, &log);
3657 #ifdef CONFIG_KVM_MMIO
3658 case KVM_REGISTER_COALESCED_MMIO: {
3659 struct kvm_coalesced_mmio_zone zone;
3662 if (copy_from_user(&zone, argp, sizeof(zone)))
3664 r = kvm_vm_ioctl_register_coalesced_mmio(kvm, &zone);
3667 case KVM_UNREGISTER_COALESCED_MMIO: {
3668 struct kvm_coalesced_mmio_zone zone;
3671 if (copy_from_user(&zone, argp, sizeof(zone)))
3673 r = kvm_vm_ioctl_unregister_coalesced_mmio(kvm, &zone);
3678 struct kvm_irqfd data;
3681 if (copy_from_user(&data, argp, sizeof(data)))
3683 r = kvm_irqfd(kvm, &data);
3686 case KVM_IOEVENTFD: {
3687 struct kvm_ioeventfd data;
3690 if (copy_from_user(&data, argp, sizeof(data)))
3692 r = kvm_ioeventfd(kvm, &data);
3695 #ifdef CONFIG_HAVE_KVM_MSI
3696 case KVM_SIGNAL_MSI: {
3700 if (copy_from_user(&msi, argp, sizeof(msi)))
3702 r = kvm_send_userspace_msi(kvm, &msi);
3706 #ifdef __KVM_HAVE_IRQ_LINE
3707 case KVM_IRQ_LINE_STATUS:
3708 case KVM_IRQ_LINE: {
3709 struct kvm_irq_level irq_event;
3712 if (copy_from_user(&irq_event, argp, sizeof(irq_event)))
3715 r = kvm_vm_ioctl_irq_line(kvm, &irq_event,
3716 ioctl == KVM_IRQ_LINE_STATUS);
3721 if (ioctl == KVM_IRQ_LINE_STATUS) {
3722 if (copy_to_user(argp, &irq_event, sizeof(irq_event)))
3730 #ifdef CONFIG_HAVE_KVM_IRQ_ROUTING
3731 case KVM_SET_GSI_ROUTING: {
3732 struct kvm_irq_routing routing;
3733 struct kvm_irq_routing __user *urouting;
3734 struct kvm_irq_routing_entry *entries = NULL;
3737 if (copy_from_user(&routing, argp, sizeof(routing)))
3740 if (!kvm_arch_can_set_irq_routing(kvm))
3742 if (routing.nr > KVM_MAX_IRQ_ROUTES)
3748 entries = vmalloc(array_size(sizeof(*entries),
3754 if (copy_from_user(entries, urouting->entries,
3755 routing.nr * sizeof(*entries)))
3756 goto out_free_irq_routing;
3758 r = kvm_set_irq_routing(kvm, entries, routing.nr,
3760 out_free_irq_routing:
3764 #endif /* CONFIG_HAVE_KVM_IRQ_ROUTING */
3765 case KVM_CREATE_DEVICE: {
3766 struct kvm_create_device cd;
3769 if (copy_from_user(&cd, argp, sizeof(cd)))
3772 r = kvm_ioctl_create_device(kvm, &cd);
3777 if (copy_to_user(argp, &cd, sizeof(cd)))
3783 case KVM_CHECK_EXTENSION:
3784 r = kvm_vm_ioctl_check_extension_generic(kvm, arg);
3787 r = kvm_arch_vm_ioctl(filp, ioctl, arg);
3793 #ifdef CONFIG_KVM_COMPAT
3794 struct compat_kvm_dirty_log {
3798 compat_uptr_t dirty_bitmap; /* one bit per page */
3803 static long kvm_vm_compat_ioctl(struct file *filp,
3804 unsigned int ioctl, unsigned long arg)
3806 struct kvm *kvm = filp->private_data;
3809 if (kvm->mm != current->mm)
3812 case KVM_GET_DIRTY_LOG: {
3813 struct compat_kvm_dirty_log compat_log;
3814 struct kvm_dirty_log log;
3816 if (copy_from_user(&compat_log, (void __user *)arg,
3817 sizeof(compat_log)))
3819 log.slot = compat_log.slot;
3820 log.padding1 = compat_log.padding1;
3821 log.padding2 = compat_log.padding2;
3822 log.dirty_bitmap = compat_ptr(compat_log.dirty_bitmap);
3824 r = kvm_vm_ioctl_get_dirty_log(kvm, &log);
3828 r = kvm_vm_ioctl(filp, ioctl, arg);
3834 static struct file_operations kvm_vm_fops = {
3835 .release = kvm_vm_release,
3836 .unlocked_ioctl = kvm_vm_ioctl,
3837 .llseek = noop_llseek,
3838 KVM_COMPAT(kvm_vm_compat_ioctl),
3841 static int kvm_dev_ioctl_create_vm(unsigned long type)
3847 kvm = kvm_create_vm(type);
3849 return PTR_ERR(kvm);
3850 #ifdef CONFIG_KVM_MMIO
3851 r = kvm_coalesced_mmio_init(kvm);
3855 r = get_unused_fd_flags(O_CLOEXEC);
3859 file = anon_inode_getfile("kvm-vm", &kvm_vm_fops, kvm, O_RDWR);
3867 * Don't call kvm_put_kvm anymore at this point; file->f_op is
3868 * already set, with ->release() being kvm_vm_release(). In error
3869 * cases it will be called by the final fput(file) and will take
3870 * care of doing kvm_put_kvm(kvm).
3872 if (kvm_create_vm_debugfs(kvm, r) < 0) {
3877 kvm_uevent_notify_change(KVM_EVENT_CREATE_VM, kvm);
3879 fd_install(r, file);
3887 static long kvm_dev_ioctl(struct file *filp,
3888 unsigned int ioctl, unsigned long arg)
3893 case KVM_GET_API_VERSION:
3896 r = KVM_API_VERSION;
3899 r = kvm_dev_ioctl_create_vm(arg);
3901 case KVM_CHECK_EXTENSION:
3902 r = kvm_vm_ioctl_check_extension_generic(NULL, arg);
3904 case KVM_GET_VCPU_MMAP_SIZE:
3907 r = PAGE_SIZE; /* struct kvm_run */
3909 r += PAGE_SIZE; /* pio data page */
3911 #ifdef CONFIG_KVM_MMIO
3912 r += PAGE_SIZE; /* coalesced mmio ring page */
3915 case KVM_TRACE_ENABLE:
3916 case KVM_TRACE_PAUSE:
3917 case KVM_TRACE_DISABLE:
3921 return kvm_arch_dev_ioctl(filp, ioctl, arg);
3927 static struct file_operations kvm_chardev_ops = {
3928 .unlocked_ioctl = kvm_dev_ioctl,
3929 .llseek = noop_llseek,
3930 KVM_COMPAT(kvm_dev_ioctl),
3933 static struct miscdevice kvm_dev = {
3939 static void hardware_enable_nolock(void *junk)
3941 int cpu = raw_smp_processor_id();
3944 if (cpumask_test_cpu(cpu, cpus_hardware_enabled))
3947 cpumask_set_cpu(cpu, cpus_hardware_enabled);
3949 r = kvm_arch_hardware_enable();
3952 cpumask_clear_cpu(cpu, cpus_hardware_enabled);
3953 atomic_inc(&hardware_enable_failed);
3954 pr_info("kvm: enabling virtualization on CPU%d failed\n", cpu);
3958 static int kvm_starting_cpu(unsigned int cpu)
3960 raw_spin_lock(&kvm_count_lock);
3961 if (kvm_usage_count)
3962 hardware_enable_nolock(NULL);
3963 raw_spin_unlock(&kvm_count_lock);
3967 static void hardware_disable_nolock(void *junk)
3969 int cpu = raw_smp_processor_id();
3971 if (!cpumask_test_cpu(cpu, cpus_hardware_enabled))
3973 cpumask_clear_cpu(cpu, cpus_hardware_enabled);
3974 kvm_arch_hardware_disable();
3977 static int kvm_dying_cpu(unsigned int cpu)
3979 raw_spin_lock(&kvm_count_lock);
3980 if (kvm_usage_count)
3981 hardware_disable_nolock(NULL);
3982 raw_spin_unlock(&kvm_count_lock);
3986 static void hardware_disable_all_nolock(void)
3988 BUG_ON(!kvm_usage_count);
3991 if (!kvm_usage_count)
3992 on_each_cpu(hardware_disable_nolock, NULL, 1);
3995 static void hardware_disable_all(void)
3997 raw_spin_lock(&kvm_count_lock);
3998 hardware_disable_all_nolock();
3999 raw_spin_unlock(&kvm_count_lock);
4002 static int hardware_enable_all(void)
4006 raw_spin_lock(&kvm_count_lock);
4009 if (kvm_usage_count == 1) {
4010 atomic_set(&hardware_enable_failed, 0);
4011 on_each_cpu(hardware_enable_nolock, NULL, 1);
4013 if (atomic_read(&hardware_enable_failed)) {
4014 hardware_disable_all_nolock();
4019 raw_spin_unlock(&kvm_count_lock);
4024 static int kvm_reboot(struct notifier_block *notifier, unsigned long val,
4028 * Some (well, at least mine) BIOSes hang on reboot if
4031 * And Intel TXT required VMX off for all cpu when system shutdown.
4033 pr_info("kvm: exiting hardware virtualization\n");
4034 kvm_rebooting = true;
4035 on_each_cpu(hardware_disable_nolock, NULL, 1);
4039 static struct notifier_block kvm_reboot_notifier = {
4040 .notifier_call = kvm_reboot,
4044 static void kvm_io_bus_destroy(struct kvm_io_bus *bus)
4048 for (i = 0; i < bus->dev_count; i++) {
4049 struct kvm_io_device *pos = bus->range[i].dev;
4051 kvm_iodevice_destructor(pos);
4056 static inline int kvm_io_bus_cmp(const struct kvm_io_range *r1,
4057 const struct kvm_io_range *r2)
4059 gpa_t addr1 = r1->addr;
4060 gpa_t addr2 = r2->addr;
4065 /* If r2->len == 0, match the exact address. If r2->len != 0,
4066 * accept any overlapping write. Any order is acceptable for
4067 * overlapping ranges, because kvm_io_bus_get_first_dev ensures
4068 * we process all of them.
4081 static int kvm_io_bus_sort_cmp(const void *p1, const void *p2)
4083 return kvm_io_bus_cmp(p1, p2);
4086 static int kvm_io_bus_get_first_dev(struct kvm_io_bus *bus,
4087 gpa_t addr, int len)
4089 struct kvm_io_range *range, key;
4092 key = (struct kvm_io_range) {
4097 range = bsearch(&key, bus->range, bus->dev_count,
4098 sizeof(struct kvm_io_range), kvm_io_bus_sort_cmp);
4102 off = range - bus->range;
4104 while (off > 0 && kvm_io_bus_cmp(&key, &bus->range[off-1]) == 0)
4110 static int __kvm_io_bus_write(struct kvm_vcpu *vcpu, struct kvm_io_bus *bus,
4111 struct kvm_io_range *range, const void *val)
4115 idx = kvm_io_bus_get_first_dev(bus, range->addr, range->len);
4119 while (idx < bus->dev_count &&
4120 kvm_io_bus_cmp(range, &bus->range[idx]) == 0) {
4121 if (!kvm_iodevice_write(vcpu, bus->range[idx].dev, range->addr,
4130 /* kvm_io_bus_write - called under kvm->slots_lock */
4131 int kvm_io_bus_write(struct kvm_vcpu *vcpu, enum kvm_bus bus_idx, gpa_t addr,
4132 int len, const void *val)
4134 struct kvm_io_bus *bus;
4135 struct kvm_io_range range;
4138 range = (struct kvm_io_range) {
4143 bus = srcu_dereference(vcpu->kvm->buses[bus_idx], &vcpu->kvm->srcu);
4146 r = __kvm_io_bus_write(vcpu, bus, &range, val);
4147 return r < 0 ? r : 0;
4149 EXPORT_SYMBOL_GPL(kvm_io_bus_write);
4151 /* kvm_io_bus_write_cookie - called under kvm->slots_lock */
4152 int kvm_io_bus_write_cookie(struct kvm_vcpu *vcpu, enum kvm_bus bus_idx,
4153 gpa_t addr, int len, const void *val, long cookie)
4155 struct kvm_io_bus *bus;
4156 struct kvm_io_range range;
4158 range = (struct kvm_io_range) {
4163 bus = srcu_dereference(vcpu->kvm->buses[bus_idx], &vcpu->kvm->srcu);
4167 /* First try the device referenced by cookie. */
4168 if ((cookie >= 0) && (cookie < bus->dev_count) &&
4169 (kvm_io_bus_cmp(&range, &bus->range[cookie]) == 0))
4170 if (!kvm_iodevice_write(vcpu, bus->range[cookie].dev, addr, len,
4175 * cookie contained garbage; fall back to search and return the
4176 * correct cookie value.
4178 return __kvm_io_bus_write(vcpu, bus, &range, val);
4181 static int __kvm_io_bus_read(struct kvm_vcpu *vcpu, struct kvm_io_bus *bus,
4182 struct kvm_io_range *range, void *val)
4186 idx = kvm_io_bus_get_first_dev(bus, range->addr, range->len);
4190 while (idx < bus->dev_count &&
4191 kvm_io_bus_cmp(range, &bus->range[idx]) == 0) {
4192 if (!kvm_iodevice_read(vcpu, bus->range[idx].dev, range->addr,
4201 /* kvm_io_bus_read - called under kvm->slots_lock */
4202 int kvm_io_bus_read(struct kvm_vcpu *vcpu, enum kvm_bus bus_idx, gpa_t addr,
4205 struct kvm_io_bus *bus;
4206 struct kvm_io_range range;
4209 range = (struct kvm_io_range) {
4214 bus = srcu_dereference(vcpu->kvm->buses[bus_idx], &vcpu->kvm->srcu);
4217 r = __kvm_io_bus_read(vcpu, bus, &range, val);
4218 return r < 0 ? r : 0;
4221 /* Caller must hold slots_lock. */
4222 int kvm_io_bus_register_dev(struct kvm *kvm, enum kvm_bus bus_idx, gpa_t addr,
4223 int len, struct kvm_io_device *dev)
4226 struct kvm_io_bus *new_bus, *bus;
4227 struct kvm_io_range range;
4229 bus = kvm_get_bus(kvm, bus_idx);
4233 /* exclude ioeventfd which is limited by maximum fd */
4234 if (bus->dev_count - bus->ioeventfd_count > NR_IOBUS_DEVS - 1)
4237 new_bus = kmalloc(struct_size(bus, range, bus->dev_count + 1),
4238 GFP_KERNEL_ACCOUNT);
4242 range = (struct kvm_io_range) {
4248 for (i = 0; i < bus->dev_count; i++)
4249 if (kvm_io_bus_cmp(&bus->range[i], &range) > 0)
4252 memcpy(new_bus, bus, sizeof(*bus) + i * sizeof(struct kvm_io_range));
4253 new_bus->dev_count++;
4254 new_bus->range[i] = range;
4255 memcpy(new_bus->range + i + 1, bus->range + i,
4256 (bus->dev_count - i) * sizeof(struct kvm_io_range));
4257 rcu_assign_pointer(kvm->buses[bus_idx], new_bus);
4258 synchronize_srcu_expedited(&kvm->srcu);
4264 /* Caller must hold slots_lock. */
4265 void kvm_io_bus_unregister_dev(struct kvm *kvm, enum kvm_bus bus_idx,
4266 struct kvm_io_device *dev)
4269 struct kvm_io_bus *new_bus, *bus;
4271 bus = kvm_get_bus(kvm, bus_idx);
4275 for (i = 0; i < bus->dev_count; i++)
4276 if (bus->range[i].dev == dev) {
4280 if (i == bus->dev_count)
4283 new_bus = kmalloc(struct_size(bus, range, bus->dev_count - 1),
4284 GFP_KERNEL_ACCOUNT);
4286 pr_err("kvm: failed to shrink bus, removing it completely\n");
4290 memcpy(new_bus, bus, sizeof(*bus) + i * sizeof(struct kvm_io_range));
4291 new_bus->dev_count--;
4292 memcpy(new_bus->range + i, bus->range + i + 1,
4293 (new_bus->dev_count - i) * sizeof(struct kvm_io_range));
4296 rcu_assign_pointer(kvm->buses[bus_idx], new_bus);
4297 synchronize_srcu_expedited(&kvm->srcu);
4302 struct kvm_io_device *kvm_io_bus_get_dev(struct kvm *kvm, enum kvm_bus bus_idx,
4305 struct kvm_io_bus *bus;
4306 int dev_idx, srcu_idx;
4307 struct kvm_io_device *iodev = NULL;
4309 srcu_idx = srcu_read_lock(&kvm->srcu);
4311 bus = srcu_dereference(kvm->buses[bus_idx], &kvm->srcu);
4315 dev_idx = kvm_io_bus_get_first_dev(bus, addr, 1);
4319 iodev = bus->range[dev_idx].dev;
4322 srcu_read_unlock(&kvm->srcu, srcu_idx);
4326 EXPORT_SYMBOL_GPL(kvm_io_bus_get_dev);
4328 static int kvm_debugfs_open(struct inode *inode, struct file *file,
4329 int (*get)(void *, u64 *), int (*set)(void *, u64),
4332 struct kvm_stat_data *stat_data = (struct kvm_stat_data *)
4335 /* The debugfs files are a reference to the kvm struct which
4336 * is still valid when kvm_destroy_vm is called.
4337 * To avoid the race between open and the removal of the debugfs
4338 * directory we test against the users count.
4340 if (!refcount_inc_not_zero(&stat_data->kvm->users_count))
4343 if (simple_attr_open(inode, file, get,
4344 KVM_DBGFS_GET_MODE(stat_data->dbgfs_item) & 0222
4347 kvm_put_kvm(stat_data->kvm);
4354 static int kvm_debugfs_release(struct inode *inode, struct file *file)
4356 struct kvm_stat_data *stat_data = (struct kvm_stat_data *)
4359 simple_attr_release(inode, file);
4360 kvm_put_kvm(stat_data->kvm);
4365 static int kvm_get_stat_per_vm(struct kvm *kvm, size_t offset, u64 *val)
4367 *val = *(ulong *)((void *)kvm + offset);
4372 static int kvm_clear_stat_per_vm(struct kvm *kvm, size_t offset)
4374 *(ulong *)((void *)kvm + offset) = 0;
4379 static int kvm_get_stat_per_vcpu(struct kvm *kvm, size_t offset, u64 *val)
4382 struct kvm_vcpu *vcpu;
4386 kvm_for_each_vcpu(i, vcpu, kvm)
4387 *val += *(u64 *)((void *)vcpu + offset);
4392 static int kvm_clear_stat_per_vcpu(struct kvm *kvm, size_t offset)
4395 struct kvm_vcpu *vcpu;
4397 kvm_for_each_vcpu(i, vcpu, kvm)
4398 *(u64 *)((void *)vcpu + offset) = 0;
4403 static int kvm_stat_data_get(void *data, u64 *val)
4406 struct kvm_stat_data *stat_data = (struct kvm_stat_data *)data;
4408 switch (stat_data->dbgfs_item->kind) {
4410 r = kvm_get_stat_per_vm(stat_data->kvm,
4411 stat_data->dbgfs_item->offset, val);
4414 r = kvm_get_stat_per_vcpu(stat_data->kvm,
4415 stat_data->dbgfs_item->offset, val);
4422 static int kvm_stat_data_clear(void *data, u64 val)
4425 struct kvm_stat_data *stat_data = (struct kvm_stat_data *)data;
4430 switch (stat_data->dbgfs_item->kind) {
4432 r = kvm_clear_stat_per_vm(stat_data->kvm,
4433 stat_data->dbgfs_item->offset);
4436 r = kvm_clear_stat_per_vcpu(stat_data->kvm,
4437 stat_data->dbgfs_item->offset);
4444 static int kvm_stat_data_open(struct inode *inode, struct file *file)
4446 __simple_attr_check_format("%llu\n", 0ull);
4447 return kvm_debugfs_open(inode, file, kvm_stat_data_get,
4448 kvm_stat_data_clear, "%llu\n");
4451 static const struct file_operations stat_fops_per_vm = {
4452 .owner = THIS_MODULE,
4453 .open = kvm_stat_data_open,
4454 .release = kvm_debugfs_release,
4455 .read = simple_attr_read,
4456 .write = simple_attr_write,
4457 .llseek = no_llseek,
4460 static int vm_stat_get(void *_offset, u64 *val)
4462 unsigned offset = (long)_offset;
4467 mutex_lock(&kvm_lock);
4468 list_for_each_entry(kvm, &vm_list, vm_list) {
4469 kvm_get_stat_per_vm(kvm, offset, &tmp_val);
4472 mutex_unlock(&kvm_lock);
4476 static int vm_stat_clear(void *_offset, u64 val)
4478 unsigned offset = (long)_offset;
4484 mutex_lock(&kvm_lock);
4485 list_for_each_entry(kvm, &vm_list, vm_list) {
4486 kvm_clear_stat_per_vm(kvm, offset);
4488 mutex_unlock(&kvm_lock);
4493 DEFINE_SIMPLE_ATTRIBUTE(vm_stat_fops, vm_stat_get, vm_stat_clear, "%llu\n");
4495 static int vcpu_stat_get(void *_offset, u64 *val)
4497 unsigned offset = (long)_offset;
4502 mutex_lock(&kvm_lock);
4503 list_for_each_entry(kvm, &vm_list, vm_list) {
4504 kvm_get_stat_per_vcpu(kvm, offset, &tmp_val);
4507 mutex_unlock(&kvm_lock);
4511 static int vcpu_stat_clear(void *_offset, u64 val)
4513 unsigned offset = (long)_offset;
4519 mutex_lock(&kvm_lock);
4520 list_for_each_entry(kvm, &vm_list, vm_list) {
4521 kvm_clear_stat_per_vcpu(kvm, offset);
4523 mutex_unlock(&kvm_lock);
4528 DEFINE_SIMPLE_ATTRIBUTE(vcpu_stat_fops, vcpu_stat_get, vcpu_stat_clear,
4531 static const struct file_operations *stat_fops[] = {
4532 [KVM_STAT_VCPU] = &vcpu_stat_fops,
4533 [KVM_STAT_VM] = &vm_stat_fops,
4536 static void kvm_uevent_notify_change(unsigned int type, struct kvm *kvm)
4538 struct kobj_uevent_env *env;
4539 unsigned long long created, active;
4541 if (!kvm_dev.this_device || !kvm)
4544 mutex_lock(&kvm_lock);
4545 if (type == KVM_EVENT_CREATE_VM) {
4546 kvm_createvm_count++;
4548 } else if (type == KVM_EVENT_DESTROY_VM) {
4551 created = kvm_createvm_count;
4552 active = kvm_active_vms;
4553 mutex_unlock(&kvm_lock);
4555 env = kzalloc(sizeof(*env), GFP_KERNEL_ACCOUNT);
4559 add_uevent_var(env, "CREATED=%llu", created);
4560 add_uevent_var(env, "COUNT=%llu", active);
4562 if (type == KVM_EVENT_CREATE_VM) {
4563 add_uevent_var(env, "EVENT=create");
4564 kvm->userspace_pid = task_pid_nr(current);
4565 } else if (type == KVM_EVENT_DESTROY_VM) {
4566 add_uevent_var(env, "EVENT=destroy");
4568 add_uevent_var(env, "PID=%d", kvm->userspace_pid);
4570 if (!IS_ERR_OR_NULL(kvm->debugfs_dentry)) {
4571 char *tmp, *p = kmalloc(PATH_MAX, GFP_KERNEL_ACCOUNT);
4574 tmp = dentry_path_raw(kvm->debugfs_dentry, p, PATH_MAX);
4576 add_uevent_var(env, "STATS_PATH=%s", tmp);
4580 /* no need for checks, since we are adding at most only 5 keys */
4581 env->envp[env->envp_idx++] = NULL;
4582 kobject_uevent_env(&kvm_dev.this_device->kobj, KOBJ_CHANGE, env->envp);
4586 static void kvm_init_debug(void)
4588 struct kvm_stats_debugfs_item *p;
4590 kvm_debugfs_dir = debugfs_create_dir("kvm", NULL);
4592 kvm_debugfs_num_entries = 0;
4593 for (p = debugfs_entries; p->name; ++p, kvm_debugfs_num_entries++) {
4594 debugfs_create_file(p->name, KVM_DBGFS_GET_MODE(p),
4595 kvm_debugfs_dir, (void *)(long)p->offset,
4596 stat_fops[p->kind]);
4600 static int kvm_suspend(void)
4602 if (kvm_usage_count)
4603 hardware_disable_nolock(NULL);
4607 static void kvm_resume(void)
4609 if (kvm_usage_count) {
4610 #ifdef CONFIG_LOCKDEP
4611 WARN_ON(lockdep_is_held(&kvm_count_lock));
4613 hardware_enable_nolock(NULL);
4617 static struct syscore_ops kvm_syscore_ops = {
4618 .suspend = kvm_suspend,
4619 .resume = kvm_resume,
4623 struct kvm_vcpu *preempt_notifier_to_vcpu(struct preempt_notifier *pn)
4625 return container_of(pn, struct kvm_vcpu, preempt_notifier);
4628 static void kvm_sched_in(struct preempt_notifier *pn, int cpu)
4630 struct kvm_vcpu *vcpu = preempt_notifier_to_vcpu(pn);
4632 WRITE_ONCE(vcpu->preempted, false);
4633 WRITE_ONCE(vcpu->ready, false);
4635 __this_cpu_write(kvm_running_vcpu, vcpu);
4636 kvm_arch_sched_in(vcpu, cpu);
4637 kvm_arch_vcpu_load(vcpu, cpu);
4640 static void kvm_sched_out(struct preempt_notifier *pn,
4641 struct task_struct *next)
4643 struct kvm_vcpu *vcpu = preempt_notifier_to_vcpu(pn);
4645 if (current->state == TASK_RUNNING) {
4646 WRITE_ONCE(vcpu->preempted, true);
4647 WRITE_ONCE(vcpu->ready, true);
4649 kvm_arch_vcpu_put(vcpu);
4650 __this_cpu_write(kvm_running_vcpu, NULL);
4654 * kvm_get_running_vcpu - get the vcpu running on the current CPU.
4656 * We can disable preemption locally around accessing the per-CPU variable,
4657 * and use the resolved vcpu pointer after enabling preemption again,
4658 * because even if the current thread is migrated to another CPU, reading
4659 * the per-CPU value later will give us the same value as we update the
4660 * per-CPU variable in the preempt notifier handlers.
4662 struct kvm_vcpu *kvm_get_running_vcpu(void)
4664 struct kvm_vcpu *vcpu;
4667 vcpu = __this_cpu_read(kvm_running_vcpu);
4672 EXPORT_SYMBOL_GPL(kvm_get_running_vcpu);
4675 * kvm_get_running_vcpus - get the per-CPU array of currently running vcpus.
4677 struct kvm_vcpu * __percpu *kvm_get_running_vcpus(void)
4679 return &kvm_running_vcpu;
4682 struct kvm_cpu_compat_check {
4687 static void check_processor_compat(void *data)
4689 struct kvm_cpu_compat_check *c = data;
4691 *c->ret = kvm_arch_check_processor_compat(c->opaque);
4694 int kvm_init(void *opaque, unsigned vcpu_size, unsigned vcpu_align,
4695 struct module *module)
4697 struct kvm_cpu_compat_check c;
4701 r = kvm_arch_init(opaque);
4706 * kvm_arch_init makes sure there's at most one caller
4707 * for architectures that support multiple implementations,
4708 * like intel and amd on x86.
4709 * kvm_arch_init must be called before kvm_irqfd_init to avoid creating
4710 * conflicts in case kvm is already setup for another implementation.
4712 r = kvm_irqfd_init();
4716 if (!zalloc_cpumask_var(&cpus_hardware_enabled, GFP_KERNEL)) {
4721 r = kvm_arch_hardware_setup(opaque);
4727 for_each_online_cpu(cpu) {
4728 smp_call_function_single(cpu, check_processor_compat, &c, 1);
4733 r = cpuhp_setup_state_nocalls(CPUHP_AP_KVM_STARTING, "kvm/cpu:starting",
4734 kvm_starting_cpu, kvm_dying_cpu);
4737 register_reboot_notifier(&kvm_reboot_notifier);
4739 /* A kmem cache lets us meet the alignment requirements of fx_save. */
4741 vcpu_align = __alignof__(struct kvm_vcpu);
4743 kmem_cache_create_usercopy("kvm_vcpu", vcpu_size, vcpu_align,
4745 offsetof(struct kvm_vcpu, arch),
4746 sizeof_field(struct kvm_vcpu, arch),
4748 if (!kvm_vcpu_cache) {
4753 r = kvm_async_pf_init();
4757 kvm_chardev_ops.owner = module;
4758 kvm_vm_fops.owner = module;
4759 kvm_vcpu_fops.owner = module;
4761 r = misc_register(&kvm_dev);
4763 pr_err("kvm: misc device register failed\n");
4767 register_syscore_ops(&kvm_syscore_ops);
4769 kvm_preempt_ops.sched_in = kvm_sched_in;
4770 kvm_preempt_ops.sched_out = kvm_sched_out;
4774 r = kvm_vfio_ops_init();
4780 kvm_async_pf_deinit();
4782 kmem_cache_destroy(kvm_vcpu_cache);
4784 unregister_reboot_notifier(&kvm_reboot_notifier);
4785 cpuhp_remove_state_nocalls(CPUHP_AP_KVM_STARTING);
4787 kvm_arch_hardware_unsetup();
4789 free_cpumask_var(cpus_hardware_enabled);
4797 EXPORT_SYMBOL_GPL(kvm_init);
4801 debugfs_remove_recursive(kvm_debugfs_dir);
4802 misc_deregister(&kvm_dev);
4803 kmem_cache_destroy(kvm_vcpu_cache);
4804 kvm_async_pf_deinit();
4805 unregister_syscore_ops(&kvm_syscore_ops);
4806 unregister_reboot_notifier(&kvm_reboot_notifier);
4807 cpuhp_remove_state_nocalls(CPUHP_AP_KVM_STARTING);
4808 on_each_cpu(hardware_disable_nolock, NULL, 1);
4809 kvm_arch_hardware_unsetup();
4812 free_cpumask_var(cpus_hardware_enabled);
4813 kvm_vfio_ops_exit();
4815 EXPORT_SYMBOL_GPL(kvm_exit);
4817 struct kvm_vm_worker_thread_context {
4819 struct task_struct *parent;
4820 struct completion init_done;
4821 kvm_vm_thread_fn_t thread_fn;
4826 static int kvm_vm_worker_thread(void *context)
4829 * The init_context is allocated on the stack of the parent thread, so
4830 * we have to locally copy anything that is needed beyond initialization
4832 struct kvm_vm_worker_thread_context *init_context = context;
4833 struct kvm *kvm = init_context->kvm;
4834 kvm_vm_thread_fn_t thread_fn = init_context->thread_fn;
4835 uintptr_t data = init_context->data;
4838 err = kthread_park(current);
4839 /* kthread_park(current) is never supposed to return an error */
4844 err = cgroup_attach_task_all(init_context->parent, current);
4846 kvm_err("%s: cgroup_attach_task_all failed with err %d\n",
4851 set_user_nice(current, task_nice(init_context->parent));
4854 init_context->err = err;
4855 complete(&init_context->init_done);
4856 init_context = NULL;
4861 /* Wait to be woken up by the spawner before proceeding. */
4864 if (!kthread_should_stop())
4865 err = thread_fn(kvm, data);
4870 int kvm_vm_create_worker_thread(struct kvm *kvm, kvm_vm_thread_fn_t thread_fn,
4871 uintptr_t data, const char *name,
4872 struct task_struct **thread_ptr)
4874 struct kvm_vm_worker_thread_context init_context = {};
4875 struct task_struct *thread;
4878 init_context.kvm = kvm;
4879 init_context.parent = current;
4880 init_context.thread_fn = thread_fn;
4881 init_context.data = data;
4882 init_completion(&init_context.init_done);
4884 thread = kthread_run(kvm_vm_worker_thread, &init_context,
4885 "%s-%d", name, task_pid_nr(current));
4887 return PTR_ERR(thread);
4889 /* kthread_run is never supposed to return NULL */
4890 WARN_ON(thread == NULL);
4892 wait_for_completion(&init_context.init_done);
4894 if (!init_context.err)
4895 *thread_ptr = thread;
4897 return init_context.err;