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];
1746 * Fast pin a writable pfn only if it is a write fault request
1747 * or the caller allows to map a writable pfn for a read fault
1750 if (!(write_fault
|| writable
))
1753 npages
= __get_user_pages_fast(addr
, 1, 1, page
);
1755 *pfn
= page_to_pfn(page
[0]);
1766 * The slow path to get the pfn of the specified host virtual address,
1767 * 1 indicates success, -errno is returned if error is detected.
1769 static int hva_to_pfn_slow(unsigned long addr
, bool *async
, bool write_fault
,
1770 bool *writable
, kvm_pfn_t
*pfn
)
1772 unsigned int flags
= FOLL_HWPOISON
;
1779 *writable
= write_fault
;
1782 flags
|= FOLL_WRITE
;
1784 flags
|= FOLL_NOWAIT
;
1786 npages
= get_user_pages_unlocked(addr
, 1, &page
, flags
);
1790 /* map read fault as writable if possible */
1791 if (unlikely(!write_fault
) && writable
) {
1794 if (__get_user_pages_fast(addr
, 1, 1, &wpage
) == 1) {
1800 *pfn
= page_to_pfn(page
);
1804 static bool vma_is_valid(struct vm_area_struct
*vma
, bool write_fault
)
1806 if (unlikely(!(vma
->vm_flags
& VM_READ
)))
1809 if (write_fault
&& (unlikely(!(vma
->vm_flags
& VM_WRITE
))))
1815 static int hva_to_pfn_remapped(struct vm_area_struct
*vma
,
1816 unsigned long addr
, bool *async
,
1817 bool write_fault
, bool *writable
,
1823 r
= follow_pfn(vma
, addr
, &pfn
);
1826 * get_user_pages fails for VM_IO and VM_PFNMAP vmas and does
1827 * not call the fault handler, so do it here.
1829 bool unlocked
= false;
1830 r
= fixup_user_fault(current
, current
->mm
, addr
,
1831 (write_fault
? FAULT_FLAG_WRITE
: 0),
1838 r
= follow_pfn(vma
, addr
, &pfn
);
1848 * Get a reference here because callers of *hva_to_pfn* and
1849 * *gfn_to_pfn* ultimately call kvm_release_pfn_clean on the
1850 * returned pfn. This is only needed if the VMA has VM_MIXEDMAP
1851 * set, but the kvm_get_pfn/kvm_release_pfn_clean pair will
1852 * simply do nothing for reserved pfns.
1854 * Whoever called remap_pfn_range is also going to call e.g.
1855 * unmap_mapping_range before the underlying pages are freed,
1856 * causing a call to our MMU notifier.
1865 * Pin guest page in memory and return its pfn.
1866 * @addr: host virtual address which maps memory to the guest
1867 * @atomic: whether this function can sleep
1868 * @async: whether this function need to wait IO complete if the
1869 * host page is not in the memory
1870 * @write_fault: whether we should get a writable host page
1871 * @writable: whether it allows to map a writable host page for !@write_fault
1873 * The function will map a writable host page for these two cases:
1874 * 1): @write_fault = true
1875 * 2): @write_fault = false && @writable, @writable will tell the caller
1876 * whether the mapping is writable.
1878 static kvm_pfn_t
hva_to_pfn(unsigned long addr
, bool atomic
, bool *async
,
1879 bool write_fault
, bool *writable
)
1881 struct vm_area_struct
*vma
;
1885 /* we can do it either atomically or asynchronously, not both */
1886 BUG_ON(atomic
&& async
);
1888 if (hva_to_pfn_fast(addr
, write_fault
, writable
, &pfn
))
1892 return KVM_PFN_ERR_FAULT
;
1894 npages
= hva_to_pfn_slow(addr
, async
, write_fault
, writable
, &pfn
);
1898 down_read(¤t
->mm
->mmap_sem
);
1899 if (npages
== -EHWPOISON
||
1900 (!async
&& check_user_page_hwpoison(addr
))) {
1901 pfn
= KVM_PFN_ERR_HWPOISON
;
1906 vma
= find_vma_intersection(current
->mm
, addr
, addr
+ 1);
1909 pfn
= KVM_PFN_ERR_FAULT
;
1910 else if (vma
->vm_flags
& (VM_IO
| VM_PFNMAP
)) {
1911 r
= hva_to_pfn_remapped(vma
, addr
, async
, write_fault
, writable
, &pfn
);
1915 pfn
= KVM_PFN_ERR_FAULT
;
1917 if (async
&& vma_is_valid(vma
, write_fault
))
1919 pfn
= KVM_PFN_ERR_FAULT
;
1922 up_read(¤t
->mm
->mmap_sem
);
1926 kvm_pfn_t
__gfn_to_pfn_memslot(struct kvm_memory_slot
*slot
, gfn_t gfn
,
1927 bool atomic
, bool *async
, bool write_fault
,
1930 unsigned long addr
= __gfn_to_hva_many(slot
, gfn
, NULL
, write_fault
);
1932 if (addr
== KVM_HVA_ERR_RO_BAD
) {
1935 return KVM_PFN_ERR_RO_FAULT
;
1938 if (kvm_is_error_hva(addr
)) {
1941 return KVM_PFN_NOSLOT
;
1944 /* Do not map writable pfn in the readonly memslot. */
1945 if (writable
&& memslot_is_readonly(slot
)) {
1950 return hva_to_pfn(addr
, atomic
, async
, write_fault
,
1953 EXPORT_SYMBOL_GPL(__gfn_to_pfn_memslot
);
1955 kvm_pfn_t
gfn_to_pfn_prot(struct kvm
*kvm
, gfn_t gfn
, bool write_fault
,
1958 return __gfn_to_pfn_memslot(gfn_to_memslot(kvm
, gfn
), gfn
, false, NULL
,
1959 write_fault
, writable
);
1961 EXPORT_SYMBOL_GPL(gfn_to_pfn_prot
);
1963 kvm_pfn_t
gfn_to_pfn_memslot(struct kvm_memory_slot
*slot
, gfn_t gfn
)
1965 return __gfn_to_pfn_memslot(slot
, gfn
, false, NULL
, true, NULL
);
1967 EXPORT_SYMBOL_GPL(gfn_to_pfn_memslot
);
1969 kvm_pfn_t
gfn_to_pfn_memslot_atomic(struct kvm_memory_slot
*slot
, gfn_t gfn
)
1971 return __gfn_to_pfn_memslot(slot
, gfn
, true, NULL
, true, NULL
);
1973 EXPORT_SYMBOL_GPL(gfn_to_pfn_memslot_atomic
);
1975 kvm_pfn_t
kvm_vcpu_gfn_to_pfn_atomic(struct kvm_vcpu
*vcpu
, gfn_t gfn
)
1977 return gfn_to_pfn_memslot_atomic(kvm_vcpu_gfn_to_memslot(vcpu
, gfn
), gfn
);
1979 EXPORT_SYMBOL_GPL(kvm_vcpu_gfn_to_pfn_atomic
);
1981 kvm_pfn_t
gfn_to_pfn(struct kvm
*kvm
, gfn_t gfn
)
1983 return gfn_to_pfn_memslot(gfn_to_memslot(kvm
, gfn
), gfn
);
1985 EXPORT_SYMBOL_GPL(gfn_to_pfn
);
1987 kvm_pfn_t
kvm_vcpu_gfn_to_pfn(struct kvm_vcpu
*vcpu
, gfn_t gfn
)
1989 return gfn_to_pfn_memslot(kvm_vcpu_gfn_to_memslot(vcpu
, gfn
), gfn
);
1991 EXPORT_SYMBOL_GPL(kvm_vcpu_gfn_to_pfn
);
1993 int gfn_to_page_many_atomic(struct kvm_memory_slot
*slot
, gfn_t gfn
,
1994 struct page
**pages
, int nr_pages
)
1999 addr
= gfn_to_hva_many(slot
, gfn
, &entry
);
2000 if (kvm_is_error_hva(addr
))
2003 if (entry
< nr_pages
)
2006 return __get_user_pages_fast(addr
, nr_pages
, 1, pages
);
2008 EXPORT_SYMBOL_GPL(gfn_to_page_many_atomic
);
2010 static struct page
*kvm_pfn_to_page(kvm_pfn_t pfn
)
2012 if (is_error_noslot_pfn(pfn
))
2013 return KVM_ERR_PTR_BAD_PAGE
;
2015 if (kvm_is_reserved_pfn(pfn
)) {
2017 return KVM_ERR_PTR_BAD_PAGE
;
2020 return pfn_to_page(pfn
);
2023 struct page
*gfn_to_page(struct kvm
*kvm
, gfn_t gfn
)
2027 pfn
= gfn_to_pfn(kvm
, gfn
);
2029 return kvm_pfn_to_page(pfn
);
2031 EXPORT_SYMBOL_GPL(gfn_to_page
);
2033 void kvm_release_pfn(kvm_pfn_t pfn
, bool dirty
, struct gfn_to_pfn_cache
*cache
)
2039 cache
->pfn
= cache
->gfn
= 0;
2042 kvm_release_pfn_dirty(pfn
);
2044 kvm_release_pfn_clean(pfn
);
2047 static void kvm_cache_gfn_to_pfn(struct kvm_memory_slot
*slot
, gfn_t gfn
,
2048 struct gfn_to_pfn_cache
*cache
, u64 gen
)
2050 kvm_release_pfn(cache
->pfn
, cache
->dirty
, cache
);
2052 cache
->pfn
= gfn_to_pfn_memslot(slot
, gfn
);
2054 cache
->dirty
= false;
2055 cache
->generation
= gen
;
2058 static int __kvm_map_gfn(struct kvm_memslots
*slots
, gfn_t gfn
,
2059 struct kvm_host_map
*map
,
2060 struct gfn_to_pfn_cache
*cache
,
2065 struct page
*page
= KVM_UNMAPPED_PAGE
;
2066 struct kvm_memory_slot
*slot
= __gfn_to_memslot(slots
, gfn
);
2067 u64 gen
= slots
->generation
;
2073 if (!cache
->pfn
|| cache
->gfn
!= gfn
||
2074 cache
->generation
!= gen
) {
2077 kvm_cache_gfn_to_pfn(slot
, gfn
, cache
, gen
);
2083 pfn
= gfn_to_pfn_memslot(slot
, gfn
);
2085 if (is_error_noslot_pfn(pfn
))
2088 if (pfn_valid(pfn
)) {
2089 page
= pfn_to_page(pfn
);
2091 hva
= kmap_atomic(page
);
2094 #ifdef CONFIG_HAS_IOMEM
2095 } else if (!atomic
) {
2096 hva
= memremap(pfn_to_hpa(pfn
), PAGE_SIZE
, MEMREMAP_WB
);
2113 int kvm_map_gfn(struct kvm_vcpu
*vcpu
, gfn_t gfn
, struct kvm_host_map
*map
,
2114 struct gfn_to_pfn_cache
*cache
, bool atomic
)
2116 return __kvm_map_gfn(kvm_memslots(vcpu
->kvm
), gfn
, map
,
2119 EXPORT_SYMBOL_GPL(kvm_map_gfn
);
2121 int kvm_vcpu_map(struct kvm_vcpu
*vcpu
, gfn_t gfn
, struct kvm_host_map
*map
)
2123 return __kvm_map_gfn(kvm_vcpu_memslots(vcpu
), gfn
, map
,
2126 EXPORT_SYMBOL_GPL(kvm_vcpu_map
);
2128 static void __kvm_unmap_gfn(struct kvm_memory_slot
*memslot
,
2129 struct kvm_host_map
*map
,
2130 struct gfn_to_pfn_cache
*cache
,
2131 bool dirty
, bool atomic
)
2139 if (map
->page
!= KVM_UNMAPPED_PAGE
) {
2141 kunmap_atomic(map
->hva
);
2145 #ifdef CONFIG_HAS_IOMEM
2149 WARN_ONCE(1, "Unexpected unmapping in atomic context");
2153 mark_page_dirty_in_slot(memslot
, map
->gfn
);
2156 cache
->dirty
|= dirty
;
2158 kvm_release_pfn(map
->pfn
, dirty
, NULL
);
2164 int kvm_unmap_gfn(struct kvm_vcpu
*vcpu
, struct kvm_host_map
*map
,
2165 struct gfn_to_pfn_cache
*cache
, bool dirty
, bool atomic
)
2167 __kvm_unmap_gfn(gfn_to_memslot(vcpu
->kvm
, map
->gfn
), map
,
2168 cache
, dirty
, atomic
);
2171 EXPORT_SYMBOL_GPL(kvm_unmap_gfn
);
2173 void kvm_vcpu_unmap(struct kvm_vcpu
*vcpu
, struct kvm_host_map
*map
, bool dirty
)
2175 __kvm_unmap_gfn(kvm_vcpu_gfn_to_memslot(vcpu
, map
->gfn
), map
, NULL
,
2178 EXPORT_SYMBOL_GPL(kvm_vcpu_unmap
);
2180 struct page
*kvm_vcpu_gfn_to_page(struct kvm_vcpu
*vcpu
, gfn_t gfn
)
2184 pfn
= kvm_vcpu_gfn_to_pfn(vcpu
, gfn
);
2186 return kvm_pfn_to_page(pfn
);
2188 EXPORT_SYMBOL_GPL(kvm_vcpu_gfn_to_page
);
2190 void kvm_release_page_clean(struct page
*page
)
2192 WARN_ON(is_error_page(page
));
2194 kvm_release_pfn_clean(page_to_pfn(page
));
2196 EXPORT_SYMBOL_GPL(kvm_release_page_clean
);
2198 void kvm_release_pfn_clean(kvm_pfn_t pfn
)
2200 if (!is_error_noslot_pfn(pfn
) && !kvm_is_reserved_pfn(pfn
))
2201 put_page(pfn_to_page(pfn
));
2203 EXPORT_SYMBOL_GPL(kvm_release_pfn_clean
);
2205 void kvm_release_page_dirty(struct page
*page
)
2207 WARN_ON(is_error_page(page
));
2209 kvm_release_pfn_dirty(page_to_pfn(page
));
2211 EXPORT_SYMBOL_GPL(kvm_release_page_dirty
);
2213 void kvm_release_pfn_dirty(kvm_pfn_t pfn
)
2215 kvm_set_pfn_dirty(pfn
);
2216 kvm_release_pfn_clean(pfn
);
2218 EXPORT_SYMBOL_GPL(kvm_release_pfn_dirty
);
2220 void kvm_set_pfn_dirty(kvm_pfn_t pfn
)
2222 if (!kvm_is_reserved_pfn(pfn
) && !kvm_is_zone_device_pfn(pfn
))
2223 SetPageDirty(pfn_to_page(pfn
));
2225 EXPORT_SYMBOL_GPL(kvm_set_pfn_dirty
);
2227 void kvm_set_pfn_accessed(kvm_pfn_t pfn
)
2229 if (!kvm_is_reserved_pfn(pfn
) && !kvm_is_zone_device_pfn(pfn
))
2230 mark_page_accessed(pfn_to_page(pfn
));
2232 EXPORT_SYMBOL_GPL(kvm_set_pfn_accessed
);
2234 void kvm_get_pfn(kvm_pfn_t pfn
)
2236 if (!kvm_is_reserved_pfn(pfn
))
2237 get_page(pfn_to_page(pfn
));
2239 EXPORT_SYMBOL_GPL(kvm_get_pfn
);
2241 static int next_segment(unsigned long len
, int offset
)
2243 if (len
> PAGE_SIZE
- offset
)
2244 return PAGE_SIZE
- offset
;
2249 static int __kvm_read_guest_page(struct kvm_memory_slot
*slot
, gfn_t gfn
,
2250 void *data
, int offset
, int len
)
2255 addr
= gfn_to_hva_memslot_prot(slot
, gfn
, NULL
);
2256 if (kvm_is_error_hva(addr
))
2258 r
= __copy_from_user(data
, (void __user
*)addr
+ offset
, len
);
2264 int kvm_read_guest_page(struct kvm
*kvm
, gfn_t gfn
, void *data
, int offset
,
2267 struct kvm_memory_slot
*slot
= gfn_to_memslot(kvm
, gfn
);
2269 return __kvm_read_guest_page(slot
, gfn
, data
, offset
, len
);
2271 EXPORT_SYMBOL_GPL(kvm_read_guest_page
);
2273 int kvm_vcpu_read_guest_page(struct kvm_vcpu
*vcpu
, gfn_t gfn
, void *data
,
2274 int offset
, int len
)
2276 struct kvm_memory_slot
*slot
= kvm_vcpu_gfn_to_memslot(vcpu
, gfn
);
2278 return __kvm_read_guest_page(slot
, gfn
, data
, offset
, len
);
2280 EXPORT_SYMBOL_GPL(kvm_vcpu_read_guest_page
);
2282 int kvm_read_guest(struct kvm
*kvm
, gpa_t gpa
, void *data
, unsigned long len
)
2284 gfn_t gfn
= gpa
>> PAGE_SHIFT
;
2286 int offset
= offset_in_page(gpa
);
2289 while ((seg
= next_segment(len
, offset
)) != 0) {
2290 ret
= kvm_read_guest_page(kvm
, gfn
, data
, offset
, seg
);
2300 EXPORT_SYMBOL_GPL(kvm_read_guest
);
2302 int kvm_vcpu_read_guest(struct kvm_vcpu
*vcpu
, gpa_t gpa
, void *data
, unsigned long len
)
2304 gfn_t gfn
= gpa
>> PAGE_SHIFT
;
2306 int offset
= offset_in_page(gpa
);
2309 while ((seg
= next_segment(len
, offset
)) != 0) {
2310 ret
= kvm_vcpu_read_guest_page(vcpu
, gfn
, data
, offset
, seg
);
2320 EXPORT_SYMBOL_GPL(kvm_vcpu_read_guest
);
2322 static int __kvm_read_guest_atomic(struct kvm_memory_slot
*slot
, gfn_t gfn
,
2323 void *data
, int offset
, unsigned long len
)
2328 addr
= gfn_to_hva_memslot_prot(slot
, gfn
, NULL
);
2329 if (kvm_is_error_hva(addr
))
2331 pagefault_disable();
2332 r
= __copy_from_user_inatomic(data
, (void __user
*)addr
+ offset
, len
);
2339 int kvm_vcpu_read_guest_atomic(struct kvm_vcpu
*vcpu
, gpa_t gpa
,
2340 void *data
, unsigned long len
)
2342 gfn_t gfn
= gpa
>> PAGE_SHIFT
;
2343 struct kvm_memory_slot
*slot
= kvm_vcpu_gfn_to_memslot(vcpu
, gfn
);
2344 int offset
= offset_in_page(gpa
);
2346 return __kvm_read_guest_atomic(slot
, gfn
, data
, offset
, len
);
2348 EXPORT_SYMBOL_GPL(kvm_vcpu_read_guest_atomic
);
2350 static int __kvm_write_guest_page(struct kvm_memory_slot
*memslot
, gfn_t gfn
,
2351 const void *data
, int offset
, int len
)
2356 addr
= gfn_to_hva_memslot(memslot
, gfn
);
2357 if (kvm_is_error_hva(addr
))
2359 r
= __copy_to_user((void __user
*)addr
+ offset
, data
, len
);
2362 mark_page_dirty_in_slot(memslot
, gfn
);
2366 int kvm_write_guest_page(struct kvm
*kvm
, gfn_t gfn
,
2367 const void *data
, int offset
, int len
)
2369 struct kvm_memory_slot
*slot
= gfn_to_memslot(kvm
, gfn
);
2371 return __kvm_write_guest_page(slot
, gfn
, data
, offset
, len
);
2373 EXPORT_SYMBOL_GPL(kvm_write_guest_page
);
2375 int kvm_vcpu_write_guest_page(struct kvm_vcpu
*vcpu
, gfn_t gfn
,
2376 const void *data
, int offset
, int len
)
2378 struct kvm_memory_slot
*slot
= kvm_vcpu_gfn_to_memslot(vcpu
, gfn
);
2380 return __kvm_write_guest_page(slot
, gfn
, data
, offset
, len
);
2382 EXPORT_SYMBOL_GPL(kvm_vcpu_write_guest_page
);
2384 int kvm_write_guest(struct kvm
*kvm
, gpa_t gpa
, const void *data
,
2387 gfn_t gfn
= gpa
>> PAGE_SHIFT
;
2389 int offset
= offset_in_page(gpa
);
2392 while ((seg
= next_segment(len
, offset
)) != 0) {
2393 ret
= kvm_write_guest_page(kvm
, gfn
, data
, offset
, seg
);
2403 EXPORT_SYMBOL_GPL(kvm_write_guest
);
2405 int kvm_vcpu_write_guest(struct kvm_vcpu
*vcpu
, gpa_t gpa
, const void *data
,
2408 gfn_t gfn
= gpa
>> PAGE_SHIFT
;
2410 int offset
= offset_in_page(gpa
);
2413 while ((seg
= next_segment(len
, offset
)) != 0) {
2414 ret
= kvm_vcpu_write_guest_page(vcpu
, gfn
, data
, offset
, seg
);
2424 EXPORT_SYMBOL_GPL(kvm_vcpu_write_guest
);
2426 static int __kvm_gfn_to_hva_cache_init(struct kvm_memslots
*slots
,
2427 struct gfn_to_hva_cache
*ghc
,
2428 gpa_t gpa
, unsigned long len
)
2430 int offset
= offset_in_page(gpa
);
2431 gfn_t start_gfn
= gpa
>> PAGE_SHIFT
;
2432 gfn_t end_gfn
= (gpa
+ len
- 1) >> PAGE_SHIFT
;
2433 gfn_t nr_pages_needed
= end_gfn
- start_gfn
+ 1;
2434 gfn_t nr_pages_avail
;
2436 /* Update ghc->generation before performing any error checks. */
2437 ghc
->generation
= slots
->generation
;
2439 if (start_gfn
> end_gfn
) {
2440 ghc
->hva
= KVM_HVA_ERR_BAD
;
2445 * If the requested region crosses two memslots, we still
2446 * verify that the entire region is valid here.
2448 for ( ; start_gfn
<= end_gfn
; start_gfn
+= nr_pages_avail
) {
2449 ghc
->memslot
= __gfn_to_memslot(slots
, start_gfn
);
2450 ghc
->hva
= gfn_to_hva_many(ghc
->memslot
, start_gfn
,
2452 if (kvm_is_error_hva(ghc
->hva
))
2456 /* Use the slow path for cross page reads and writes. */
2457 if (nr_pages_needed
== 1)
2460 ghc
->memslot
= NULL
;
2467 int kvm_gfn_to_hva_cache_init(struct kvm
*kvm
, struct gfn_to_hva_cache
*ghc
,
2468 gpa_t gpa
, unsigned long len
)
2470 struct kvm_memslots
*slots
= kvm_memslots(kvm
);
2471 return __kvm_gfn_to_hva_cache_init(slots
, ghc
, gpa
, len
);
2473 EXPORT_SYMBOL_GPL(kvm_gfn_to_hva_cache_init
);
2475 int kvm_write_guest_offset_cached(struct kvm
*kvm
, struct gfn_to_hva_cache
*ghc
,
2476 void *data
, unsigned int offset
,
2479 struct kvm_memslots
*slots
= kvm_memslots(kvm
);
2481 gpa_t gpa
= ghc
->gpa
+ offset
;
2483 BUG_ON(len
+ offset
> ghc
->len
);
2485 if (slots
->generation
!= ghc
->generation
) {
2486 if (__kvm_gfn_to_hva_cache_init(slots
, ghc
, ghc
->gpa
, ghc
->len
))
2490 if (kvm_is_error_hva(ghc
->hva
))
2493 if (unlikely(!ghc
->memslot
))
2494 return kvm_write_guest(kvm
, gpa
, data
, len
);
2496 r
= __copy_to_user((void __user
*)ghc
->hva
+ offset
, data
, len
);
2499 mark_page_dirty_in_slot(ghc
->memslot
, gpa
>> PAGE_SHIFT
);
2503 EXPORT_SYMBOL_GPL(kvm_write_guest_offset_cached
);
2505 int kvm_write_guest_cached(struct kvm
*kvm
, struct gfn_to_hva_cache
*ghc
,
2506 void *data
, unsigned long len
)
2508 return kvm_write_guest_offset_cached(kvm
, ghc
, data
, 0, len
);
2510 EXPORT_SYMBOL_GPL(kvm_write_guest_cached
);
2512 int kvm_read_guest_offset_cached(struct kvm
*kvm
, struct gfn_to_hva_cache
*ghc
,
2513 void *data
, unsigned int offset
,
2516 struct kvm_memslots
*slots
= kvm_memslots(kvm
);
2518 gpa_t gpa
= ghc
->gpa
+ offset
;
2520 BUG_ON(len
+ offset
> ghc
->len
);
2522 if (slots
->generation
!= ghc
->generation
) {
2523 if (__kvm_gfn_to_hva_cache_init(slots
, ghc
, ghc
->gpa
, ghc
->len
))
2527 if (kvm_is_error_hva(ghc
->hva
))
2530 if (unlikely(!ghc
->memslot
))
2531 return kvm_read_guest(kvm
, gpa
, data
, len
);
2533 r
= __copy_from_user(data
, (void __user
*)ghc
->hva
+ offset
, len
);
2539 EXPORT_SYMBOL_GPL(kvm_read_guest_offset_cached
);
2541 int kvm_read_guest_cached(struct kvm
*kvm
, struct gfn_to_hva_cache
*ghc
,
2542 void *data
, unsigned long len
)
2544 return kvm_read_guest_offset_cached(kvm
, ghc
, data
, 0, len
);
2546 EXPORT_SYMBOL_GPL(kvm_read_guest_cached
);
2548 int kvm_clear_guest_page(struct kvm
*kvm
, gfn_t gfn
, int offset
, int len
)
2550 const void *zero_page
= (const void *) __va(page_to_phys(ZERO_PAGE(0)));
2552 return kvm_write_guest_page(kvm
, gfn
, zero_page
, offset
, len
);
2554 EXPORT_SYMBOL_GPL(kvm_clear_guest_page
);
2556 int kvm_clear_guest(struct kvm
*kvm
, gpa_t gpa
, unsigned long len
)
2558 gfn_t gfn
= gpa
>> PAGE_SHIFT
;
2560 int offset
= offset_in_page(gpa
);
2563 while ((seg
= next_segment(len
, offset
)) != 0) {
2564 ret
= kvm_clear_guest_page(kvm
, gfn
, offset
, seg
);
2573 EXPORT_SYMBOL_GPL(kvm_clear_guest
);
2575 static void mark_page_dirty_in_slot(struct kvm_memory_slot
*memslot
,
2578 if (memslot
&& memslot
->dirty_bitmap
) {
2579 unsigned long rel_gfn
= gfn
- memslot
->base_gfn
;
2581 set_bit_le(rel_gfn
, memslot
->dirty_bitmap
);
2585 void mark_page_dirty(struct kvm
*kvm
, gfn_t gfn
)
2587 struct kvm_memory_slot
*memslot
;
2589 memslot
= gfn_to_memslot(kvm
, gfn
);
2590 mark_page_dirty_in_slot(memslot
, gfn
);
2592 EXPORT_SYMBOL_GPL(mark_page_dirty
);
2594 void kvm_vcpu_mark_page_dirty(struct kvm_vcpu
*vcpu
, gfn_t gfn
)
2596 struct kvm_memory_slot
*memslot
;
2598 memslot
= kvm_vcpu_gfn_to_memslot(vcpu
, gfn
);
2599 mark_page_dirty_in_slot(memslot
, gfn
);
2601 EXPORT_SYMBOL_GPL(kvm_vcpu_mark_page_dirty
);
2603 void kvm_sigset_activate(struct kvm_vcpu
*vcpu
)
2605 if (!vcpu
->sigset_active
)
2609 * This does a lockless modification of ->real_blocked, which is fine
2610 * because, only current can change ->real_blocked and all readers of
2611 * ->real_blocked don't care as long ->real_blocked is always a subset
2614 sigprocmask(SIG_SETMASK
, &vcpu
->sigset
, ¤t
->real_blocked
);
2617 void kvm_sigset_deactivate(struct kvm_vcpu
*vcpu
)
2619 if (!vcpu
->sigset_active
)
2622 sigprocmask(SIG_SETMASK
, ¤t
->real_blocked
, NULL
);
2623 sigemptyset(¤t
->real_blocked
);
2626 static void grow_halt_poll_ns(struct kvm_vcpu
*vcpu
)
2628 unsigned int old
, val
, grow
, grow_start
;
2630 old
= val
= vcpu
->halt_poll_ns
;
2631 grow_start
= READ_ONCE(halt_poll_ns_grow_start
);
2632 grow
= READ_ONCE(halt_poll_ns_grow
);
2637 if (val
< grow_start
)
2640 if (val
> halt_poll_ns
)
2643 vcpu
->halt_poll_ns
= val
;
2645 trace_kvm_halt_poll_ns_grow(vcpu
->vcpu_id
, val
, old
);
2648 static void shrink_halt_poll_ns(struct kvm_vcpu
*vcpu
)
2650 unsigned int old
, val
, shrink
;
2652 old
= val
= vcpu
->halt_poll_ns
;
2653 shrink
= READ_ONCE(halt_poll_ns_shrink
);
2659 vcpu
->halt_poll_ns
= val
;
2660 trace_kvm_halt_poll_ns_shrink(vcpu
->vcpu_id
, val
, old
);
2663 static int kvm_vcpu_check_block(struct kvm_vcpu
*vcpu
)
2666 int idx
= srcu_read_lock(&vcpu
->kvm
->srcu
);
2668 if (kvm_arch_vcpu_runnable(vcpu
)) {
2669 kvm_make_request(KVM_REQ_UNHALT
, vcpu
);
2672 if (kvm_cpu_has_pending_timer(vcpu
))
2674 if (signal_pending(current
))
2679 srcu_read_unlock(&vcpu
->kvm
->srcu
, idx
);
2684 update_halt_poll_stats(struct kvm_vcpu
*vcpu
, u64 poll_ns
, bool waited
)
2687 vcpu
->stat
.halt_poll_fail_ns
+= poll_ns
;
2689 vcpu
->stat
.halt_poll_success_ns
+= poll_ns
;
2693 * The vCPU has executed a HLT instruction with in-kernel mode enabled.
2695 void kvm_vcpu_block(struct kvm_vcpu
*vcpu
)
2697 ktime_t start
, cur
, poll_end
;
2698 bool waited
= false;
2701 kvm_arch_vcpu_blocking(vcpu
);
2703 start
= cur
= poll_end
= ktime_get();
2704 if (vcpu
->halt_poll_ns
&& !kvm_arch_no_poll(vcpu
)) {
2705 ktime_t stop
= ktime_add_ns(ktime_get(), vcpu
->halt_poll_ns
);
2707 ++vcpu
->stat
.halt_attempted_poll
;
2710 * This sets KVM_REQ_UNHALT if an interrupt
2713 if (kvm_vcpu_check_block(vcpu
) < 0) {
2714 ++vcpu
->stat
.halt_successful_poll
;
2715 if (!vcpu_valid_wakeup(vcpu
))
2716 ++vcpu
->stat
.halt_poll_invalid
;
2719 poll_end
= cur
= ktime_get();
2720 } while (single_task_running() && ktime_before(cur
, stop
));
2723 prepare_to_rcuwait(&vcpu
->wait
);
2725 set_current_state(TASK_INTERRUPTIBLE
);
2727 if (kvm_vcpu_check_block(vcpu
) < 0)
2733 finish_rcuwait(&vcpu
->wait
);
2736 kvm_arch_vcpu_unblocking(vcpu
);
2737 block_ns
= ktime_to_ns(cur
) - ktime_to_ns(start
);
2739 update_halt_poll_stats(
2740 vcpu
, ktime_to_ns(ktime_sub(poll_end
, start
)), waited
);
2742 if (!kvm_arch_no_poll(vcpu
)) {
2743 if (!vcpu_valid_wakeup(vcpu
)) {
2744 shrink_halt_poll_ns(vcpu
);
2745 } else if (vcpu
->kvm
->max_halt_poll_ns
) {
2746 if (block_ns
<= vcpu
->halt_poll_ns
)
2748 /* we had a long block, shrink polling */
2749 else if (vcpu
->halt_poll_ns
&&
2750 block_ns
> vcpu
->kvm
->max_halt_poll_ns
)
2751 shrink_halt_poll_ns(vcpu
);
2752 /* we had a short halt and our poll time is too small */
2753 else if (vcpu
->halt_poll_ns
< vcpu
->kvm
->max_halt_poll_ns
&&
2754 block_ns
< vcpu
->kvm
->max_halt_poll_ns
)
2755 grow_halt_poll_ns(vcpu
);
2757 vcpu
->halt_poll_ns
= 0;
2761 trace_kvm_vcpu_wakeup(block_ns
, waited
, vcpu_valid_wakeup(vcpu
));
2762 kvm_arch_vcpu_block_finish(vcpu
);
2764 EXPORT_SYMBOL_GPL(kvm_vcpu_block
);
2766 bool kvm_vcpu_wake_up(struct kvm_vcpu
*vcpu
)
2768 struct rcuwait
*waitp
;
2770 waitp
= kvm_arch_vcpu_get_wait(vcpu
);
2771 if (rcuwait_wake_up(waitp
)) {
2772 WRITE_ONCE(vcpu
->ready
, true);
2773 ++vcpu
->stat
.halt_wakeup
;
2779 EXPORT_SYMBOL_GPL(kvm_vcpu_wake_up
);
2783 * Kick a sleeping VCPU, or a guest VCPU in guest mode, into host kernel mode.
2785 void kvm_vcpu_kick(struct kvm_vcpu
*vcpu
)
2788 int cpu
= vcpu
->cpu
;
2790 if (kvm_vcpu_wake_up(vcpu
))
2794 if (cpu
!= me
&& (unsigned)cpu
< nr_cpu_ids
&& cpu_online(cpu
))
2795 if (kvm_arch_vcpu_should_kick(vcpu
))
2796 smp_send_reschedule(cpu
);
2799 EXPORT_SYMBOL_GPL(kvm_vcpu_kick
);
2800 #endif /* !CONFIG_S390 */
2802 int kvm_vcpu_yield_to(struct kvm_vcpu
*target
)
2805 struct task_struct
*task
= NULL
;
2809 pid
= rcu_dereference(target
->pid
);
2811 task
= get_pid_task(pid
, PIDTYPE_PID
);
2815 ret
= yield_to(task
, 1);
2816 put_task_struct(task
);
2820 EXPORT_SYMBOL_GPL(kvm_vcpu_yield_to
);
2823 * Helper that checks whether a VCPU is eligible for directed yield.
2824 * Most eligible candidate to yield is decided by following heuristics:
2826 * (a) VCPU which has not done pl-exit or cpu relax intercepted recently
2827 * (preempted lock holder), indicated by @in_spin_loop.
2828 * Set at the beginning and cleared at the end of interception/PLE handler.
2830 * (b) VCPU which has done pl-exit/ cpu relax intercepted but did not get
2831 * chance last time (mostly it has become eligible now since we have probably
2832 * yielded to lockholder in last iteration. This is done by toggling
2833 * @dy_eligible each time a VCPU checked for eligibility.)
2835 * Yielding to a recently pl-exited/cpu relax intercepted VCPU before yielding
2836 * to preempted lock-holder could result in wrong VCPU selection and CPU
2837 * burning. Giving priority for a potential lock-holder increases lock
2840 * Since algorithm is based on heuristics, accessing another VCPU data without
2841 * locking does not harm. It may result in trying to yield to same VCPU, fail
2842 * and continue with next VCPU and so on.
2844 static bool kvm_vcpu_eligible_for_directed_yield(struct kvm_vcpu
*vcpu
)
2846 #ifdef CONFIG_HAVE_KVM_CPU_RELAX_INTERCEPT
2849 eligible
= !vcpu
->spin_loop
.in_spin_loop
||
2850 vcpu
->spin_loop
.dy_eligible
;
2852 if (vcpu
->spin_loop
.in_spin_loop
)
2853 kvm_vcpu_set_dy_eligible(vcpu
, !vcpu
->spin_loop
.dy_eligible
);
2862 * Unlike kvm_arch_vcpu_runnable, this function is called outside
2863 * a vcpu_load/vcpu_put pair. However, for most architectures
2864 * kvm_arch_vcpu_runnable does not require vcpu_load.
2866 bool __weak
kvm_arch_dy_runnable(struct kvm_vcpu
*vcpu
)
2868 return kvm_arch_vcpu_runnable(vcpu
);
2871 static bool vcpu_dy_runnable(struct kvm_vcpu
*vcpu
)
2873 if (kvm_arch_dy_runnable(vcpu
))
2876 #ifdef CONFIG_KVM_ASYNC_PF
2877 if (!list_empty_careful(&vcpu
->async_pf
.done
))
2884 void kvm_vcpu_on_spin(struct kvm_vcpu
*me
, bool yield_to_kernel_mode
)
2886 struct kvm
*kvm
= me
->kvm
;
2887 struct kvm_vcpu
*vcpu
;
2888 int last_boosted_vcpu
= me
->kvm
->last_boosted_vcpu
;
2894 kvm_vcpu_set_in_spin_loop(me
, true);
2896 * We boost the priority of a VCPU that is runnable but not
2897 * currently running, because it got preempted by something
2898 * else and called schedule in __vcpu_run. Hopefully that
2899 * VCPU is holding the lock that we need and will release it.
2900 * We approximate round-robin by starting at the last boosted VCPU.
2902 for (pass
= 0; pass
< 2 && !yielded
&& try; pass
++) {
2903 kvm_for_each_vcpu(i
, vcpu
, kvm
) {
2904 if (!pass
&& i
<= last_boosted_vcpu
) {
2905 i
= last_boosted_vcpu
;
2907 } else if (pass
&& i
> last_boosted_vcpu
)
2909 if (!READ_ONCE(vcpu
->ready
))
2913 if (rcuwait_active(&vcpu
->wait
) &&
2914 !vcpu_dy_runnable(vcpu
))
2916 if (READ_ONCE(vcpu
->preempted
) && yield_to_kernel_mode
&&
2917 !kvm_arch_vcpu_in_kernel(vcpu
))
2919 if (!kvm_vcpu_eligible_for_directed_yield(vcpu
))
2922 yielded
= kvm_vcpu_yield_to(vcpu
);
2924 kvm
->last_boosted_vcpu
= i
;
2926 } else if (yielded
< 0) {
2933 kvm_vcpu_set_in_spin_loop(me
, false);
2935 /* Ensure vcpu is not eligible during next spinloop */
2936 kvm_vcpu_set_dy_eligible(me
, false);
2938 EXPORT_SYMBOL_GPL(kvm_vcpu_on_spin
);
2940 static vm_fault_t
kvm_vcpu_fault(struct vm_fault
*vmf
)
2942 struct kvm_vcpu
*vcpu
= vmf
->vma
->vm_file
->private_data
;
2945 if (vmf
->pgoff
== 0)
2946 page
= virt_to_page(vcpu
->run
);
2948 else if (vmf
->pgoff
== KVM_PIO_PAGE_OFFSET
)
2949 page
= virt_to_page(vcpu
->arch
.pio_data
);
2951 #ifdef CONFIG_KVM_MMIO
2952 else if (vmf
->pgoff
== KVM_COALESCED_MMIO_PAGE_OFFSET
)
2953 page
= virt_to_page(vcpu
->kvm
->coalesced_mmio_ring
);
2956 return kvm_arch_vcpu_fault(vcpu
, vmf
);
2962 static const struct vm_operations_struct kvm_vcpu_vm_ops
= {
2963 .fault
= kvm_vcpu_fault
,
2966 static int kvm_vcpu_mmap(struct file
*file
, struct vm_area_struct
*vma
)
2968 vma
->vm_ops
= &kvm_vcpu_vm_ops
;
2972 static int kvm_vcpu_release(struct inode
*inode
, struct file
*filp
)
2974 struct kvm_vcpu
*vcpu
= filp
->private_data
;
2976 debugfs_remove_recursive(vcpu
->debugfs_dentry
);
2977 kvm_put_kvm(vcpu
->kvm
);
2981 static struct file_operations kvm_vcpu_fops
= {
2982 .release
= kvm_vcpu_release
,
2983 .unlocked_ioctl
= kvm_vcpu_ioctl
,
2984 .mmap
= kvm_vcpu_mmap
,
2985 .llseek
= noop_llseek
,
2986 KVM_COMPAT(kvm_vcpu_compat_ioctl
),
2990 * Allocates an inode for the vcpu.
2992 static int create_vcpu_fd(struct kvm_vcpu
*vcpu
)
2994 char name
[8 + 1 + ITOA_MAX_LEN
+ 1];
2996 snprintf(name
, sizeof(name
), "kvm-vcpu:%d", vcpu
->vcpu_id
);
2997 return anon_inode_getfd(name
, &kvm_vcpu_fops
, vcpu
, O_RDWR
| O_CLOEXEC
);
3000 static void kvm_create_vcpu_debugfs(struct kvm_vcpu
*vcpu
)
3002 #ifdef __KVM_HAVE_ARCH_VCPU_DEBUGFS
3003 char dir_name
[ITOA_MAX_LEN
* 2];
3005 if (!debugfs_initialized())
3008 snprintf(dir_name
, sizeof(dir_name
), "vcpu%d", vcpu
->vcpu_id
);
3009 vcpu
->debugfs_dentry
= debugfs_create_dir(dir_name
,
3010 vcpu
->kvm
->debugfs_dentry
);
3012 kvm_arch_create_vcpu_debugfs(vcpu
);
3017 * Creates some virtual cpus. Good luck creating more than one.
3019 static int kvm_vm_ioctl_create_vcpu(struct kvm
*kvm
, u32 id
)
3022 struct kvm_vcpu
*vcpu
;
3025 if (id
>= KVM_MAX_VCPU_ID
)
3028 mutex_lock(&kvm
->lock
);
3029 if (kvm
->created_vcpus
== KVM_MAX_VCPUS
) {
3030 mutex_unlock(&kvm
->lock
);
3034 kvm
->created_vcpus
++;
3035 mutex_unlock(&kvm
->lock
);
3037 r
= kvm_arch_vcpu_precreate(kvm
, id
);
3039 goto vcpu_decrement
;
3041 vcpu
= kmem_cache_zalloc(kvm_vcpu_cache
, GFP_KERNEL
);
3044 goto vcpu_decrement
;
3047 BUILD_BUG_ON(sizeof(struct kvm_run
) > PAGE_SIZE
);
3048 page
= alloc_page(GFP_KERNEL
| __GFP_ZERO
);
3053 vcpu
->run
= page_address(page
);
3055 kvm_vcpu_init(vcpu
, kvm
, id
);
3057 r
= kvm_arch_vcpu_create(vcpu
);
3059 goto vcpu_free_run_page
;
3061 mutex_lock(&kvm
->lock
);
3062 if (kvm_get_vcpu_by_id(kvm
, id
)) {
3064 goto unlock_vcpu_destroy
;
3067 vcpu
->vcpu_idx
= atomic_read(&kvm
->online_vcpus
);
3068 BUG_ON(kvm
->vcpus
[vcpu
->vcpu_idx
]);
3070 /* Now it's all set up, let userspace reach it */
3072 r
= create_vcpu_fd(vcpu
);
3074 kvm_put_kvm_no_destroy(kvm
);
3075 goto unlock_vcpu_destroy
;
3078 kvm
->vcpus
[vcpu
->vcpu_idx
] = vcpu
;
3081 * Pairs with smp_rmb() in kvm_get_vcpu. Write kvm->vcpus
3082 * before kvm->online_vcpu's incremented value.
3085 atomic_inc(&kvm
->online_vcpus
);
3087 mutex_unlock(&kvm
->lock
);
3088 kvm_arch_vcpu_postcreate(vcpu
);
3089 kvm_create_vcpu_debugfs(vcpu
);
3092 unlock_vcpu_destroy
:
3093 mutex_unlock(&kvm
->lock
);
3094 kvm_arch_vcpu_destroy(vcpu
);
3096 free_page((unsigned long)vcpu
->run
);
3098 kmem_cache_free(kvm_vcpu_cache
, vcpu
);
3100 mutex_lock(&kvm
->lock
);
3101 kvm
->created_vcpus
--;
3102 mutex_unlock(&kvm
->lock
);
3106 static int kvm_vcpu_ioctl_set_sigmask(struct kvm_vcpu
*vcpu
, sigset_t
*sigset
)
3109 sigdelsetmask(sigset
, sigmask(SIGKILL
)|sigmask(SIGSTOP
));
3110 vcpu
->sigset_active
= 1;
3111 vcpu
->sigset
= *sigset
;
3113 vcpu
->sigset_active
= 0;
3117 static long kvm_vcpu_ioctl(struct file
*filp
,
3118 unsigned int ioctl
, unsigned long arg
)
3120 struct kvm_vcpu
*vcpu
= filp
->private_data
;
3121 void __user
*argp
= (void __user
*)arg
;
3123 struct kvm_fpu
*fpu
= NULL
;
3124 struct kvm_sregs
*kvm_sregs
= NULL
;
3126 if (vcpu
->kvm
->mm
!= current
->mm
)
3129 if (unlikely(_IOC_TYPE(ioctl
) != KVMIO
))
3133 * Some architectures have vcpu ioctls that are asynchronous to vcpu
3134 * execution; mutex_lock() would break them.
3136 r
= kvm_arch_vcpu_async_ioctl(filp
, ioctl
, arg
);
3137 if (r
!= -ENOIOCTLCMD
)
3140 if (mutex_lock_killable(&vcpu
->mutex
))
3148 oldpid
= rcu_access_pointer(vcpu
->pid
);
3149 if (unlikely(oldpid
!= task_pid(current
))) {
3150 /* The thread running this VCPU changed. */
3153 r
= kvm_arch_vcpu_run_pid_change(vcpu
);
3157 newpid
= get_task_pid(current
, PIDTYPE_PID
);
3158 rcu_assign_pointer(vcpu
->pid
, newpid
);
3163 r
= kvm_arch_vcpu_ioctl_run(vcpu
);
3164 trace_kvm_userspace_exit(vcpu
->run
->exit_reason
, r
);
3167 case KVM_GET_REGS
: {
3168 struct kvm_regs
*kvm_regs
;
3171 kvm_regs
= kzalloc(sizeof(struct kvm_regs
), GFP_KERNEL_ACCOUNT
);
3174 r
= kvm_arch_vcpu_ioctl_get_regs(vcpu
, kvm_regs
);
3178 if (copy_to_user(argp
, kvm_regs
, sizeof(struct kvm_regs
)))
3185 case KVM_SET_REGS
: {
3186 struct kvm_regs
*kvm_regs
;
3188 kvm_regs
= memdup_user(argp
, sizeof(*kvm_regs
));
3189 if (IS_ERR(kvm_regs
)) {
3190 r
= PTR_ERR(kvm_regs
);
3193 r
= kvm_arch_vcpu_ioctl_set_regs(vcpu
, kvm_regs
);
3197 case KVM_GET_SREGS
: {
3198 kvm_sregs
= kzalloc(sizeof(struct kvm_sregs
),
3199 GFP_KERNEL_ACCOUNT
);
3203 r
= kvm_arch_vcpu_ioctl_get_sregs(vcpu
, kvm_sregs
);
3207 if (copy_to_user(argp
, kvm_sregs
, sizeof(struct kvm_sregs
)))
3212 case KVM_SET_SREGS
: {
3213 kvm_sregs
= memdup_user(argp
, sizeof(*kvm_sregs
));
3214 if (IS_ERR(kvm_sregs
)) {
3215 r
= PTR_ERR(kvm_sregs
);
3219 r
= kvm_arch_vcpu_ioctl_set_sregs(vcpu
, kvm_sregs
);
3222 case KVM_GET_MP_STATE
: {
3223 struct kvm_mp_state mp_state
;
3225 r
= kvm_arch_vcpu_ioctl_get_mpstate(vcpu
, &mp_state
);
3229 if (copy_to_user(argp
, &mp_state
, sizeof(mp_state
)))
3234 case KVM_SET_MP_STATE
: {
3235 struct kvm_mp_state mp_state
;
3238 if (copy_from_user(&mp_state
, argp
, sizeof(mp_state
)))
3240 r
= kvm_arch_vcpu_ioctl_set_mpstate(vcpu
, &mp_state
);
3243 case KVM_TRANSLATE
: {
3244 struct kvm_translation tr
;
3247 if (copy_from_user(&tr
, argp
, sizeof(tr
)))
3249 r
= kvm_arch_vcpu_ioctl_translate(vcpu
, &tr
);
3253 if (copy_to_user(argp
, &tr
, sizeof(tr
)))
3258 case KVM_SET_GUEST_DEBUG
: {
3259 struct kvm_guest_debug dbg
;
3262 if (copy_from_user(&dbg
, argp
, sizeof(dbg
)))
3264 r
= kvm_arch_vcpu_ioctl_set_guest_debug(vcpu
, &dbg
);
3267 case KVM_SET_SIGNAL_MASK
: {
3268 struct kvm_signal_mask __user
*sigmask_arg
= argp
;
3269 struct kvm_signal_mask kvm_sigmask
;
3270 sigset_t sigset
, *p
;
3275 if (copy_from_user(&kvm_sigmask
, argp
,
3276 sizeof(kvm_sigmask
)))
3279 if (kvm_sigmask
.len
!= sizeof(sigset
))
3282 if (copy_from_user(&sigset
, sigmask_arg
->sigset
,
3287 r
= kvm_vcpu_ioctl_set_sigmask(vcpu
, p
);
3291 fpu
= kzalloc(sizeof(struct kvm_fpu
), GFP_KERNEL_ACCOUNT
);
3295 r
= kvm_arch_vcpu_ioctl_get_fpu(vcpu
, fpu
);
3299 if (copy_to_user(argp
, fpu
, sizeof(struct kvm_fpu
)))
3305 fpu
= memdup_user(argp
, sizeof(*fpu
));
3311 r
= kvm_arch_vcpu_ioctl_set_fpu(vcpu
, fpu
);
3315 r
= kvm_arch_vcpu_ioctl(filp
, ioctl
, arg
);
3318 mutex_unlock(&vcpu
->mutex
);
3324 #ifdef CONFIG_KVM_COMPAT
3325 static long kvm_vcpu_compat_ioctl(struct file
*filp
,
3326 unsigned int ioctl
, unsigned long arg
)
3328 struct kvm_vcpu
*vcpu
= filp
->private_data
;
3329 void __user
*argp
= compat_ptr(arg
);
3332 if (vcpu
->kvm
->mm
!= current
->mm
)
3336 case KVM_SET_SIGNAL_MASK
: {
3337 struct kvm_signal_mask __user
*sigmask_arg
= argp
;
3338 struct kvm_signal_mask kvm_sigmask
;
3343 if (copy_from_user(&kvm_sigmask
, argp
,
3344 sizeof(kvm_sigmask
)))
3347 if (kvm_sigmask
.len
!= sizeof(compat_sigset_t
))
3350 if (get_compat_sigset(&sigset
, (void *)sigmask_arg
->sigset
))
3352 r
= kvm_vcpu_ioctl_set_sigmask(vcpu
, &sigset
);
3354 r
= kvm_vcpu_ioctl_set_sigmask(vcpu
, NULL
);
3358 r
= kvm_vcpu_ioctl(filp
, ioctl
, arg
);
3366 static int kvm_device_mmap(struct file
*filp
, struct vm_area_struct
*vma
)
3368 struct kvm_device
*dev
= filp
->private_data
;
3371 return dev
->ops
->mmap(dev
, vma
);
3376 static int kvm_device_ioctl_attr(struct kvm_device
*dev
,
3377 int (*accessor
)(struct kvm_device
*dev
,
3378 struct kvm_device_attr
*attr
),
3381 struct kvm_device_attr attr
;
3386 if (copy_from_user(&attr
, (void __user
*)arg
, sizeof(attr
)))
3389 return accessor(dev
, &attr
);
3392 static long kvm_device_ioctl(struct file
*filp
, unsigned int ioctl
,
3395 struct kvm_device
*dev
= filp
->private_data
;
3397 if (dev
->kvm
->mm
!= current
->mm
)
3401 case KVM_SET_DEVICE_ATTR
:
3402 return kvm_device_ioctl_attr(dev
, dev
->ops
->set_attr
, arg
);
3403 case KVM_GET_DEVICE_ATTR
:
3404 return kvm_device_ioctl_attr(dev
, dev
->ops
->get_attr
, arg
);
3405 case KVM_HAS_DEVICE_ATTR
:
3406 return kvm_device_ioctl_attr(dev
, dev
->ops
->has_attr
, arg
);
3408 if (dev
->ops
->ioctl
)
3409 return dev
->ops
->ioctl(dev
, ioctl
, arg
);
3415 static int kvm_device_release(struct inode
*inode
, struct file
*filp
)
3417 struct kvm_device
*dev
= filp
->private_data
;
3418 struct kvm
*kvm
= dev
->kvm
;
3420 if (dev
->ops
->release
) {
3421 mutex_lock(&kvm
->lock
);
3422 list_del(&dev
->vm_node
);
3423 dev
->ops
->release(dev
);
3424 mutex_unlock(&kvm
->lock
);
3431 static const struct file_operations kvm_device_fops
= {
3432 .unlocked_ioctl
= kvm_device_ioctl
,
3433 .release
= kvm_device_release
,
3434 KVM_COMPAT(kvm_device_ioctl
),
3435 .mmap
= kvm_device_mmap
,
3438 struct kvm_device
*kvm_device_from_filp(struct file
*filp
)
3440 if (filp
->f_op
!= &kvm_device_fops
)
3443 return filp
->private_data
;
3446 static const struct kvm_device_ops
*kvm_device_ops_table
[KVM_DEV_TYPE_MAX
] = {
3447 #ifdef CONFIG_KVM_MPIC
3448 [KVM_DEV_TYPE_FSL_MPIC_20
] = &kvm_mpic_ops
,
3449 [KVM_DEV_TYPE_FSL_MPIC_42
] = &kvm_mpic_ops
,
3453 int kvm_register_device_ops(const struct kvm_device_ops
*ops
, u32 type
)
3455 if (type
>= ARRAY_SIZE(kvm_device_ops_table
))
3458 if (kvm_device_ops_table
[type
] != NULL
)
3461 kvm_device_ops_table
[type
] = ops
;
3465 void kvm_unregister_device_ops(u32 type
)
3467 if (kvm_device_ops_table
[type
] != NULL
)
3468 kvm_device_ops_table
[type
] = NULL
;
3471 static int kvm_ioctl_create_device(struct kvm
*kvm
,
3472 struct kvm_create_device
*cd
)
3474 const struct kvm_device_ops
*ops
= NULL
;
3475 struct kvm_device
*dev
;
3476 bool test
= cd
->flags
& KVM_CREATE_DEVICE_TEST
;
3480 if (cd
->type
>= ARRAY_SIZE(kvm_device_ops_table
))
3483 type
= array_index_nospec(cd
->type
, ARRAY_SIZE(kvm_device_ops_table
));
3484 ops
= kvm_device_ops_table
[type
];
3491 dev
= kzalloc(sizeof(*dev
), GFP_KERNEL_ACCOUNT
);
3498 mutex_lock(&kvm
->lock
);
3499 ret
= ops
->create(dev
, type
);
3501 mutex_unlock(&kvm
->lock
);
3505 list_add(&dev
->vm_node
, &kvm
->devices
);
3506 mutex_unlock(&kvm
->lock
);
3512 ret
= anon_inode_getfd(ops
->name
, &kvm_device_fops
, dev
, O_RDWR
| O_CLOEXEC
);
3514 kvm_put_kvm_no_destroy(kvm
);
3515 mutex_lock(&kvm
->lock
);
3516 list_del(&dev
->vm_node
);
3517 mutex_unlock(&kvm
->lock
);
3526 static long kvm_vm_ioctl_check_extension_generic(struct kvm
*kvm
, long arg
)
3529 case KVM_CAP_USER_MEMORY
:
3530 case KVM_CAP_DESTROY_MEMORY_REGION_WORKS
:
3531 case KVM_CAP_JOIN_MEMORY_REGIONS_WORKS
:
3532 case KVM_CAP_INTERNAL_ERROR_DATA
:
3533 #ifdef CONFIG_HAVE_KVM_MSI
3534 case KVM_CAP_SIGNAL_MSI
:
3536 #ifdef CONFIG_HAVE_KVM_IRQFD
3538 case KVM_CAP_IRQFD_RESAMPLE
:
3540 case KVM_CAP_IOEVENTFD_ANY_LENGTH
:
3541 case KVM_CAP_CHECK_EXTENSION_VM
:
3542 case KVM_CAP_ENABLE_CAP_VM
:
3543 case KVM_CAP_HALT_POLL
:
3545 #ifdef CONFIG_KVM_MMIO
3546 case KVM_CAP_COALESCED_MMIO
:
3547 return KVM_COALESCED_MMIO_PAGE_OFFSET
;
3548 case KVM_CAP_COALESCED_PIO
:
3551 #ifdef CONFIG_KVM_GENERIC_DIRTYLOG_READ_PROTECT
3552 case KVM_CAP_MANUAL_DIRTY_LOG_PROTECT2
:
3553 return KVM_DIRTY_LOG_MANUAL_CAPS
;
3555 #ifdef CONFIG_HAVE_KVM_IRQ_ROUTING
3556 case KVM_CAP_IRQ_ROUTING
:
3557 return KVM_MAX_IRQ_ROUTES
;
3559 #if KVM_ADDRESS_SPACE_NUM > 1
3560 case KVM_CAP_MULTI_ADDRESS_SPACE
:
3561 return KVM_ADDRESS_SPACE_NUM
;
3563 case KVM_CAP_NR_MEMSLOTS
:
3564 return KVM_USER_MEM_SLOTS
;
3568 return kvm_vm_ioctl_check_extension(kvm
, arg
);
3571 int __attribute__((weak
)) kvm_vm_ioctl_enable_cap(struct kvm
*kvm
,
3572 struct kvm_enable_cap
*cap
)
3577 static int kvm_vm_ioctl_enable_cap_generic(struct kvm
*kvm
,
3578 struct kvm_enable_cap
*cap
)
3581 #ifdef CONFIG_KVM_GENERIC_DIRTYLOG_READ_PROTECT
3582 case KVM_CAP_MANUAL_DIRTY_LOG_PROTECT2
: {
3583 u64 allowed_options
= KVM_DIRTY_LOG_MANUAL_PROTECT_ENABLE
;
3585 if (cap
->args
[0] & KVM_DIRTY_LOG_MANUAL_PROTECT_ENABLE
)
3586 allowed_options
= KVM_DIRTY_LOG_MANUAL_CAPS
;
3588 if (cap
->flags
|| (cap
->args
[0] & ~allowed_options
))
3590 kvm
->manual_dirty_log_protect
= cap
->args
[0];
3594 case KVM_CAP_HALT_POLL
: {
3595 if (cap
->flags
|| cap
->args
[0] != (unsigned int)cap
->args
[0])
3598 kvm
->max_halt_poll_ns
= cap
->args
[0];
3602 return kvm_vm_ioctl_enable_cap(kvm
, cap
);
3606 static long kvm_vm_ioctl(struct file
*filp
,
3607 unsigned int ioctl
, unsigned long arg
)
3609 struct kvm
*kvm
= filp
->private_data
;
3610 void __user
*argp
= (void __user
*)arg
;
3613 if (kvm
->mm
!= current
->mm
)
3616 case KVM_CREATE_VCPU
:
3617 r
= kvm_vm_ioctl_create_vcpu(kvm
, arg
);
3619 case KVM_ENABLE_CAP
: {
3620 struct kvm_enable_cap cap
;
3623 if (copy_from_user(&cap
, argp
, sizeof(cap
)))
3625 r
= kvm_vm_ioctl_enable_cap_generic(kvm
, &cap
);
3628 case KVM_SET_USER_MEMORY_REGION
: {
3629 struct kvm_userspace_memory_region kvm_userspace_mem
;
3632 if (copy_from_user(&kvm_userspace_mem
, argp
,
3633 sizeof(kvm_userspace_mem
)))
3636 r
= kvm_vm_ioctl_set_memory_region(kvm
, &kvm_userspace_mem
);
3639 case KVM_GET_DIRTY_LOG
: {
3640 struct kvm_dirty_log log
;
3643 if (copy_from_user(&log
, argp
, sizeof(log
)))
3645 r
= kvm_vm_ioctl_get_dirty_log(kvm
, &log
);
3648 #ifdef CONFIG_KVM_GENERIC_DIRTYLOG_READ_PROTECT
3649 case KVM_CLEAR_DIRTY_LOG
: {
3650 struct kvm_clear_dirty_log log
;
3653 if (copy_from_user(&log
, argp
, sizeof(log
)))
3655 r
= kvm_vm_ioctl_clear_dirty_log(kvm
, &log
);
3659 #ifdef CONFIG_KVM_MMIO
3660 case KVM_REGISTER_COALESCED_MMIO
: {
3661 struct kvm_coalesced_mmio_zone zone
;
3664 if (copy_from_user(&zone
, argp
, sizeof(zone
)))
3666 r
= kvm_vm_ioctl_register_coalesced_mmio(kvm
, &zone
);
3669 case KVM_UNREGISTER_COALESCED_MMIO
: {
3670 struct kvm_coalesced_mmio_zone zone
;
3673 if (copy_from_user(&zone
, argp
, sizeof(zone
)))
3675 r
= kvm_vm_ioctl_unregister_coalesced_mmio(kvm
, &zone
);
3680 struct kvm_irqfd data
;
3683 if (copy_from_user(&data
, argp
, sizeof(data
)))
3685 r
= kvm_irqfd(kvm
, &data
);
3688 case KVM_IOEVENTFD
: {
3689 struct kvm_ioeventfd data
;
3692 if (copy_from_user(&data
, argp
, sizeof(data
)))
3694 r
= kvm_ioeventfd(kvm
, &data
);
3697 #ifdef CONFIG_HAVE_KVM_MSI
3698 case KVM_SIGNAL_MSI
: {
3702 if (copy_from_user(&msi
, argp
, sizeof(msi
)))
3704 r
= kvm_send_userspace_msi(kvm
, &msi
);
3708 #ifdef __KVM_HAVE_IRQ_LINE
3709 case KVM_IRQ_LINE_STATUS
:
3710 case KVM_IRQ_LINE
: {
3711 struct kvm_irq_level irq_event
;
3714 if (copy_from_user(&irq_event
, argp
, sizeof(irq_event
)))
3717 r
= kvm_vm_ioctl_irq_line(kvm
, &irq_event
,
3718 ioctl
== KVM_IRQ_LINE_STATUS
);
3723 if (ioctl
== KVM_IRQ_LINE_STATUS
) {
3724 if (copy_to_user(argp
, &irq_event
, sizeof(irq_event
)))
3732 #ifdef CONFIG_HAVE_KVM_IRQ_ROUTING
3733 case KVM_SET_GSI_ROUTING
: {
3734 struct kvm_irq_routing routing
;
3735 struct kvm_irq_routing __user
*urouting
;
3736 struct kvm_irq_routing_entry
*entries
= NULL
;
3739 if (copy_from_user(&routing
, argp
, sizeof(routing
)))
3742 if (!kvm_arch_can_set_irq_routing(kvm
))
3744 if (routing
.nr
> KVM_MAX_IRQ_ROUTES
)
3750 entries
= vmalloc(array_size(sizeof(*entries
),
3756 if (copy_from_user(entries
, urouting
->entries
,
3757 routing
.nr
* sizeof(*entries
)))
3758 goto out_free_irq_routing
;
3760 r
= kvm_set_irq_routing(kvm
, entries
, routing
.nr
,
3762 out_free_irq_routing
:
3766 #endif /* CONFIG_HAVE_KVM_IRQ_ROUTING */
3767 case KVM_CREATE_DEVICE
: {
3768 struct kvm_create_device cd
;
3771 if (copy_from_user(&cd
, argp
, sizeof(cd
)))
3774 r
= kvm_ioctl_create_device(kvm
, &cd
);
3779 if (copy_to_user(argp
, &cd
, sizeof(cd
)))
3785 case KVM_CHECK_EXTENSION
:
3786 r
= kvm_vm_ioctl_check_extension_generic(kvm
, arg
);
3789 r
= kvm_arch_vm_ioctl(filp
, ioctl
, arg
);
3795 #ifdef CONFIG_KVM_COMPAT
3796 struct compat_kvm_dirty_log
{
3800 compat_uptr_t dirty_bitmap
; /* one bit per page */
3805 static long kvm_vm_compat_ioctl(struct file
*filp
,
3806 unsigned int ioctl
, unsigned long arg
)
3808 struct kvm
*kvm
= filp
->private_data
;
3811 if (kvm
->mm
!= current
->mm
)
3814 case KVM_GET_DIRTY_LOG
: {
3815 struct compat_kvm_dirty_log compat_log
;
3816 struct kvm_dirty_log log
;
3818 if (copy_from_user(&compat_log
, (void __user
*)arg
,
3819 sizeof(compat_log
)))
3821 log
.slot
= compat_log
.slot
;
3822 log
.padding1
= compat_log
.padding1
;
3823 log
.padding2
= compat_log
.padding2
;
3824 log
.dirty_bitmap
= compat_ptr(compat_log
.dirty_bitmap
);
3826 r
= kvm_vm_ioctl_get_dirty_log(kvm
, &log
);
3830 r
= kvm_vm_ioctl(filp
, ioctl
, arg
);
3836 static struct file_operations kvm_vm_fops
= {
3837 .release
= kvm_vm_release
,
3838 .unlocked_ioctl
= kvm_vm_ioctl
,
3839 .llseek
= noop_llseek
,
3840 KVM_COMPAT(kvm_vm_compat_ioctl
),
3843 static int kvm_dev_ioctl_create_vm(unsigned long type
)
3849 kvm
= kvm_create_vm(type
);
3851 return PTR_ERR(kvm
);
3852 #ifdef CONFIG_KVM_MMIO
3853 r
= kvm_coalesced_mmio_init(kvm
);
3857 r
= get_unused_fd_flags(O_CLOEXEC
);
3861 file
= anon_inode_getfile("kvm-vm", &kvm_vm_fops
, kvm
, O_RDWR
);
3869 * Don't call kvm_put_kvm anymore at this point; file->f_op is
3870 * already set, with ->release() being kvm_vm_release(). In error
3871 * cases it will be called by the final fput(file) and will take
3872 * care of doing kvm_put_kvm(kvm).
3874 if (kvm_create_vm_debugfs(kvm
, r
) < 0) {
3879 kvm_uevent_notify_change(KVM_EVENT_CREATE_VM
, kvm
);
3881 fd_install(r
, file
);
3889 static long kvm_dev_ioctl(struct file
*filp
,
3890 unsigned int ioctl
, unsigned long arg
)
3895 case KVM_GET_API_VERSION
:
3898 r
= KVM_API_VERSION
;
3901 r
= kvm_dev_ioctl_create_vm(arg
);
3903 case KVM_CHECK_EXTENSION
:
3904 r
= kvm_vm_ioctl_check_extension_generic(NULL
, arg
);
3906 case KVM_GET_VCPU_MMAP_SIZE
:
3909 r
= PAGE_SIZE
; /* struct kvm_run */
3911 r
+= PAGE_SIZE
; /* pio data page */
3913 #ifdef CONFIG_KVM_MMIO
3914 r
+= PAGE_SIZE
; /* coalesced mmio ring page */
3917 case KVM_TRACE_ENABLE
:
3918 case KVM_TRACE_PAUSE
:
3919 case KVM_TRACE_DISABLE
:
3923 return kvm_arch_dev_ioctl(filp
, ioctl
, arg
);
3929 static struct file_operations kvm_chardev_ops
= {
3930 .unlocked_ioctl
= kvm_dev_ioctl
,
3931 .llseek
= noop_llseek
,
3932 KVM_COMPAT(kvm_dev_ioctl
),
3935 static struct miscdevice kvm_dev
= {
3941 static void hardware_enable_nolock(void *junk
)
3943 int cpu
= raw_smp_processor_id();
3946 if (cpumask_test_cpu(cpu
, cpus_hardware_enabled
))
3949 cpumask_set_cpu(cpu
, cpus_hardware_enabled
);
3951 r
= kvm_arch_hardware_enable();
3954 cpumask_clear_cpu(cpu
, cpus_hardware_enabled
);
3955 atomic_inc(&hardware_enable_failed
);
3956 pr_info("kvm: enabling virtualization on CPU%d failed\n", cpu
);
3960 static int kvm_starting_cpu(unsigned int cpu
)
3962 raw_spin_lock(&kvm_count_lock
);
3963 if (kvm_usage_count
)
3964 hardware_enable_nolock(NULL
);
3965 raw_spin_unlock(&kvm_count_lock
);
3969 static void hardware_disable_nolock(void *junk
)
3971 int cpu
= raw_smp_processor_id();
3973 if (!cpumask_test_cpu(cpu
, cpus_hardware_enabled
))
3975 cpumask_clear_cpu(cpu
, cpus_hardware_enabled
);
3976 kvm_arch_hardware_disable();
3979 static int kvm_dying_cpu(unsigned int cpu
)
3981 raw_spin_lock(&kvm_count_lock
);
3982 if (kvm_usage_count
)
3983 hardware_disable_nolock(NULL
);
3984 raw_spin_unlock(&kvm_count_lock
);
3988 static void hardware_disable_all_nolock(void)
3990 BUG_ON(!kvm_usage_count
);
3993 if (!kvm_usage_count
)
3994 on_each_cpu(hardware_disable_nolock
, NULL
, 1);
3997 static void hardware_disable_all(void)
3999 raw_spin_lock(&kvm_count_lock
);
4000 hardware_disable_all_nolock();
4001 raw_spin_unlock(&kvm_count_lock
);
4004 static int hardware_enable_all(void)
4008 raw_spin_lock(&kvm_count_lock
);
4011 if (kvm_usage_count
== 1) {
4012 atomic_set(&hardware_enable_failed
, 0);
4013 on_each_cpu(hardware_enable_nolock
, NULL
, 1);
4015 if (atomic_read(&hardware_enable_failed
)) {
4016 hardware_disable_all_nolock();
4021 raw_spin_unlock(&kvm_count_lock
);
4026 static int kvm_reboot(struct notifier_block
*notifier
, unsigned long val
,
4030 * Some (well, at least mine) BIOSes hang on reboot if
4033 * And Intel TXT required VMX off for all cpu when system shutdown.
4035 pr_info("kvm: exiting hardware virtualization\n");
4036 kvm_rebooting
= true;
4037 on_each_cpu(hardware_disable_nolock
, NULL
, 1);
4041 static struct notifier_block kvm_reboot_notifier
= {
4042 .notifier_call
= kvm_reboot
,
4046 static void kvm_io_bus_destroy(struct kvm_io_bus
*bus
)
4050 for (i
= 0; i
< bus
->dev_count
; i
++) {
4051 struct kvm_io_device
*pos
= bus
->range
[i
].dev
;
4053 kvm_iodevice_destructor(pos
);
4058 static inline int kvm_io_bus_cmp(const struct kvm_io_range
*r1
,
4059 const struct kvm_io_range
*r2
)
4061 gpa_t addr1
= r1
->addr
;
4062 gpa_t addr2
= r2
->addr
;
4067 /* If r2->len == 0, match the exact address. If r2->len != 0,
4068 * accept any overlapping write. Any order is acceptable for
4069 * overlapping ranges, because kvm_io_bus_get_first_dev ensures
4070 * we process all of them.
4083 static int kvm_io_bus_sort_cmp(const void *p1
, const void *p2
)
4085 return kvm_io_bus_cmp(p1
, p2
);
4088 static int kvm_io_bus_get_first_dev(struct kvm_io_bus
*bus
,
4089 gpa_t addr
, int len
)
4091 struct kvm_io_range
*range
, key
;
4094 key
= (struct kvm_io_range
) {
4099 range
= bsearch(&key
, bus
->range
, bus
->dev_count
,
4100 sizeof(struct kvm_io_range
), kvm_io_bus_sort_cmp
);
4104 off
= range
- bus
->range
;
4106 while (off
> 0 && kvm_io_bus_cmp(&key
, &bus
->range
[off
-1]) == 0)
4112 static int __kvm_io_bus_write(struct kvm_vcpu
*vcpu
, struct kvm_io_bus
*bus
,
4113 struct kvm_io_range
*range
, const void *val
)
4117 idx
= kvm_io_bus_get_first_dev(bus
, range
->addr
, range
->len
);
4121 while (idx
< bus
->dev_count
&&
4122 kvm_io_bus_cmp(range
, &bus
->range
[idx
]) == 0) {
4123 if (!kvm_iodevice_write(vcpu
, bus
->range
[idx
].dev
, range
->addr
,
4132 /* kvm_io_bus_write - called under kvm->slots_lock */
4133 int kvm_io_bus_write(struct kvm_vcpu
*vcpu
, enum kvm_bus bus_idx
, gpa_t addr
,
4134 int len
, const void *val
)
4136 struct kvm_io_bus
*bus
;
4137 struct kvm_io_range range
;
4140 range
= (struct kvm_io_range
) {
4145 bus
= srcu_dereference(vcpu
->kvm
->buses
[bus_idx
], &vcpu
->kvm
->srcu
);
4148 r
= __kvm_io_bus_write(vcpu
, bus
, &range
, val
);
4149 return r
< 0 ? r
: 0;
4151 EXPORT_SYMBOL_GPL(kvm_io_bus_write
);
4153 /* kvm_io_bus_write_cookie - called under kvm->slots_lock */
4154 int kvm_io_bus_write_cookie(struct kvm_vcpu
*vcpu
, enum kvm_bus bus_idx
,
4155 gpa_t addr
, int len
, const void *val
, long cookie
)
4157 struct kvm_io_bus
*bus
;
4158 struct kvm_io_range range
;
4160 range
= (struct kvm_io_range
) {
4165 bus
= srcu_dereference(vcpu
->kvm
->buses
[bus_idx
], &vcpu
->kvm
->srcu
);
4169 /* First try the device referenced by cookie. */
4170 if ((cookie
>= 0) && (cookie
< bus
->dev_count
) &&
4171 (kvm_io_bus_cmp(&range
, &bus
->range
[cookie
]) == 0))
4172 if (!kvm_iodevice_write(vcpu
, bus
->range
[cookie
].dev
, addr
, len
,
4177 * cookie contained garbage; fall back to search and return the
4178 * correct cookie value.
4180 return __kvm_io_bus_write(vcpu
, bus
, &range
, val
);
4183 static int __kvm_io_bus_read(struct kvm_vcpu
*vcpu
, struct kvm_io_bus
*bus
,
4184 struct kvm_io_range
*range
, void *val
)
4188 idx
= kvm_io_bus_get_first_dev(bus
, range
->addr
, range
->len
);
4192 while (idx
< bus
->dev_count
&&
4193 kvm_io_bus_cmp(range
, &bus
->range
[idx
]) == 0) {
4194 if (!kvm_iodevice_read(vcpu
, bus
->range
[idx
].dev
, range
->addr
,
4203 /* kvm_io_bus_read - called under kvm->slots_lock */
4204 int kvm_io_bus_read(struct kvm_vcpu
*vcpu
, enum kvm_bus bus_idx
, gpa_t addr
,
4207 struct kvm_io_bus
*bus
;
4208 struct kvm_io_range range
;
4211 range
= (struct kvm_io_range
) {
4216 bus
= srcu_dereference(vcpu
->kvm
->buses
[bus_idx
], &vcpu
->kvm
->srcu
);
4219 r
= __kvm_io_bus_read(vcpu
, bus
, &range
, val
);
4220 return r
< 0 ? r
: 0;
4223 /* Caller must hold slots_lock. */
4224 int kvm_io_bus_register_dev(struct kvm
*kvm
, enum kvm_bus bus_idx
, gpa_t addr
,
4225 int len
, struct kvm_io_device
*dev
)
4228 struct kvm_io_bus
*new_bus
, *bus
;
4229 struct kvm_io_range range
;
4231 bus
= kvm_get_bus(kvm
, bus_idx
);
4235 /* exclude ioeventfd which is limited by maximum fd */
4236 if (bus
->dev_count
- bus
->ioeventfd_count
> NR_IOBUS_DEVS
- 1)
4239 new_bus
= kmalloc(struct_size(bus
, range
, bus
->dev_count
+ 1),
4240 GFP_KERNEL_ACCOUNT
);
4244 range
= (struct kvm_io_range
) {
4250 for (i
= 0; i
< bus
->dev_count
; i
++)
4251 if (kvm_io_bus_cmp(&bus
->range
[i
], &range
) > 0)
4254 memcpy(new_bus
, bus
, sizeof(*bus
) + i
* sizeof(struct kvm_io_range
));
4255 new_bus
->dev_count
++;
4256 new_bus
->range
[i
] = range
;
4257 memcpy(new_bus
->range
+ i
+ 1, bus
->range
+ i
,
4258 (bus
->dev_count
- i
) * sizeof(struct kvm_io_range
));
4259 rcu_assign_pointer(kvm
->buses
[bus_idx
], new_bus
);
4260 synchronize_srcu_expedited(&kvm
->srcu
);
4266 /* Caller must hold slots_lock. */
4267 void kvm_io_bus_unregister_dev(struct kvm
*kvm
, enum kvm_bus bus_idx
,
4268 struct kvm_io_device
*dev
)
4271 struct kvm_io_bus
*new_bus
, *bus
;
4273 bus
= kvm_get_bus(kvm
, bus_idx
);
4277 for (i
= 0; i
< bus
->dev_count
; i
++)
4278 if (bus
->range
[i
].dev
== dev
) {
4282 if (i
== bus
->dev_count
)
4285 new_bus
= kmalloc(struct_size(bus
, range
, bus
->dev_count
- 1),
4286 GFP_KERNEL_ACCOUNT
);
4288 pr_err("kvm: failed to shrink bus, removing it completely\n");
4292 memcpy(new_bus
, bus
, sizeof(*bus
) + i
* sizeof(struct kvm_io_range
));
4293 new_bus
->dev_count
--;
4294 memcpy(new_bus
->range
+ i
, bus
->range
+ i
+ 1,
4295 (new_bus
->dev_count
- i
) * sizeof(struct kvm_io_range
));
4298 rcu_assign_pointer(kvm
->buses
[bus_idx
], new_bus
);
4299 synchronize_srcu_expedited(&kvm
->srcu
);
4304 struct kvm_io_device
*kvm_io_bus_get_dev(struct kvm
*kvm
, enum kvm_bus bus_idx
,
4307 struct kvm_io_bus
*bus
;
4308 int dev_idx
, srcu_idx
;
4309 struct kvm_io_device
*iodev
= NULL
;
4311 srcu_idx
= srcu_read_lock(&kvm
->srcu
);
4313 bus
= srcu_dereference(kvm
->buses
[bus_idx
], &kvm
->srcu
);
4317 dev_idx
= kvm_io_bus_get_first_dev(bus
, addr
, 1);
4321 iodev
= bus
->range
[dev_idx
].dev
;
4324 srcu_read_unlock(&kvm
->srcu
, srcu_idx
);
4328 EXPORT_SYMBOL_GPL(kvm_io_bus_get_dev
);
4330 static int kvm_debugfs_open(struct inode
*inode
, struct file
*file
,
4331 int (*get
)(void *, u64
*), int (*set
)(void *, u64
),
4334 struct kvm_stat_data
*stat_data
= (struct kvm_stat_data
*)
4337 /* The debugfs files are a reference to the kvm struct which
4338 * is still valid when kvm_destroy_vm is called.
4339 * To avoid the race between open and the removal of the debugfs
4340 * directory we test against the users count.
4342 if (!refcount_inc_not_zero(&stat_data
->kvm
->users_count
))
4345 if (simple_attr_open(inode
, file
, get
,
4346 KVM_DBGFS_GET_MODE(stat_data
->dbgfs_item
) & 0222
4349 kvm_put_kvm(stat_data
->kvm
);
4356 static int kvm_debugfs_release(struct inode
*inode
, struct file
*file
)
4358 struct kvm_stat_data
*stat_data
= (struct kvm_stat_data
*)
4361 simple_attr_release(inode
, file
);
4362 kvm_put_kvm(stat_data
->kvm
);
4367 static int kvm_get_stat_per_vm(struct kvm
*kvm
, size_t offset
, u64
*val
)
4369 *val
= *(ulong
*)((void *)kvm
+ offset
);
4374 static int kvm_clear_stat_per_vm(struct kvm
*kvm
, size_t offset
)
4376 *(ulong
*)((void *)kvm
+ offset
) = 0;
4381 static int kvm_get_stat_per_vcpu(struct kvm
*kvm
, size_t offset
, u64
*val
)
4384 struct kvm_vcpu
*vcpu
;
4388 kvm_for_each_vcpu(i
, vcpu
, kvm
)
4389 *val
+= *(u64
*)((void *)vcpu
+ offset
);
4394 static int kvm_clear_stat_per_vcpu(struct kvm
*kvm
, size_t offset
)
4397 struct kvm_vcpu
*vcpu
;
4399 kvm_for_each_vcpu(i
, vcpu
, kvm
)
4400 *(u64
*)((void *)vcpu
+ offset
) = 0;
4405 static int kvm_stat_data_get(void *data
, u64
*val
)
4408 struct kvm_stat_data
*stat_data
= (struct kvm_stat_data
*)data
;
4410 switch (stat_data
->dbgfs_item
->kind
) {
4412 r
= kvm_get_stat_per_vm(stat_data
->kvm
,
4413 stat_data
->dbgfs_item
->offset
, val
);
4416 r
= kvm_get_stat_per_vcpu(stat_data
->kvm
,
4417 stat_data
->dbgfs_item
->offset
, val
);
4424 static int kvm_stat_data_clear(void *data
, u64 val
)
4427 struct kvm_stat_data
*stat_data
= (struct kvm_stat_data
*)data
;
4432 switch (stat_data
->dbgfs_item
->kind
) {
4434 r
= kvm_clear_stat_per_vm(stat_data
->kvm
,
4435 stat_data
->dbgfs_item
->offset
);
4438 r
= kvm_clear_stat_per_vcpu(stat_data
->kvm
,
4439 stat_data
->dbgfs_item
->offset
);
4446 static int kvm_stat_data_open(struct inode
*inode
, struct file
*file
)
4448 __simple_attr_check_format("%llu\n", 0ull);
4449 return kvm_debugfs_open(inode
, file
, kvm_stat_data_get
,
4450 kvm_stat_data_clear
, "%llu\n");
4453 static const struct file_operations stat_fops_per_vm
= {
4454 .owner
= THIS_MODULE
,
4455 .open
= kvm_stat_data_open
,
4456 .release
= kvm_debugfs_release
,
4457 .read
= simple_attr_read
,
4458 .write
= simple_attr_write
,
4459 .llseek
= no_llseek
,
4462 static int vm_stat_get(void *_offset
, u64
*val
)
4464 unsigned offset
= (long)_offset
;
4469 mutex_lock(&kvm_lock
);
4470 list_for_each_entry(kvm
, &vm_list
, vm_list
) {
4471 kvm_get_stat_per_vm(kvm
, offset
, &tmp_val
);
4474 mutex_unlock(&kvm_lock
);
4478 static int vm_stat_clear(void *_offset
, u64 val
)
4480 unsigned offset
= (long)_offset
;
4486 mutex_lock(&kvm_lock
);
4487 list_for_each_entry(kvm
, &vm_list
, vm_list
) {
4488 kvm_clear_stat_per_vm(kvm
, offset
);
4490 mutex_unlock(&kvm_lock
);
4495 DEFINE_SIMPLE_ATTRIBUTE(vm_stat_fops
, vm_stat_get
, vm_stat_clear
, "%llu\n");
4497 static int vcpu_stat_get(void *_offset
, u64
*val
)
4499 unsigned offset
= (long)_offset
;
4504 mutex_lock(&kvm_lock
);
4505 list_for_each_entry(kvm
, &vm_list
, vm_list
) {
4506 kvm_get_stat_per_vcpu(kvm
, offset
, &tmp_val
);
4509 mutex_unlock(&kvm_lock
);
4513 static int vcpu_stat_clear(void *_offset
, u64 val
)
4515 unsigned offset
= (long)_offset
;
4521 mutex_lock(&kvm_lock
);
4522 list_for_each_entry(kvm
, &vm_list
, vm_list
) {
4523 kvm_clear_stat_per_vcpu(kvm
, offset
);
4525 mutex_unlock(&kvm_lock
);
4530 DEFINE_SIMPLE_ATTRIBUTE(vcpu_stat_fops
, vcpu_stat_get
, vcpu_stat_clear
,
4533 static const struct file_operations
*stat_fops
[] = {
4534 [KVM_STAT_VCPU
] = &vcpu_stat_fops
,
4535 [KVM_STAT_VM
] = &vm_stat_fops
,
4538 static void kvm_uevent_notify_change(unsigned int type
, struct kvm
*kvm
)
4540 struct kobj_uevent_env
*env
;
4541 unsigned long long created
, active
;
4543 if (!kvm_dev
.this_device
|| !kvm
)
4546 mutex_lock(&kvm_lock
);
4547 if (type
== KVM_EVENT_CREATE_VM
) {
4548 kvm_createvm_count
++;
4550 } else if (type
== KVM_EVENT_DESTROY_VM
) {
4553 created
= kvm_createvm_count
;
4554 active
= kvm_active_vms
;
4555 mutex_unlock(&kvm_lock
);
4557 env
= kzalloc(sizeof(*env
), GFP_KERNEL_ACCOUNT
);
4561 add_uevent_var(env
, "CREATED=%llu", created
);
4562 add_uevent_var(env
, "COUNT=%llu", active
);
4564 if (type
== KVM_EVENT_CREATE_VM
) {
4565 add_uevent_var(env
, "EVENT=create");
4566 kvm
->userspace_pid
= task_pid_nr(current
);
4567 } else if (type
== KVM_EVENT_DESTROY_VM
) {
4568 add_uevent_var(env
, "EVENT=destroy");
4570 add_uevent_var(env
, "PID=%d", kvm
->userspace_pid
);
4572 if (!IS_ERR_OR_NULL(kvm
->debugfs_dentry
)) {
4573 char *tmp
, *p
= kmalloc(PATH_MAX
, GFP_KERNEL_ACCOUNT
);
4576 tmp
= dentry_path_raw(kvm
->debugfs_dentry
, p
, PATH_MAX
);
4578 add_uevent_var(env
, "STATS_PATH=%s", tmp
);
4582 /* no need for checks, since we are adding at most only 5 keys */
4583 env
->envp
[env
->envp_idx
++] = NULL
;
4584 kobject_uevent_env(&kvm_dev
.this_device
->kobj
, KOBJ_CHANGE
, env
->envp
);
4588 static void kvm_init_debug(void)
4590 struct kvm_stats_debugfs_item
*p
;
4592 kvm_debugfs_dir
= debugfs_create_dir("kvm", NULL
);
4594 kvm_debugfs_num_entries
= 0;
4595 for (p
= debugfs_entries
; p
->name
; ++p
, kvm_debugfs_num_entries
++) {
4596 debugfs_create_file(p
->name
, KVM_DBGFS_GET_MODE(p
),
4597 kvm_debugfs_dir
, (void *)(long)p
->offset
,
4598 stat_fops
[p
->kind
]);
4602 static int kvm_suspend(void)
4604 if (kvm_usage_count
)
4605 hardware_disable_nolock(NULL
);
4609 static void kvm_resume(void)
4611 if (kvm_usage_count
) {
4612 #ifdef CONFIG_LOCKDEP
4613 WARN_ON(lockdep_is_held(&kvm_count_lock
));
4615 hardware_enable_nolock(NULL
);
4619 static struct syscore_ops kvm_syscore_ops
= {
4620 .suspend
= kvm_suspend
,
4621 .resume
= kvm_resume
,
4625 struct kvm_vcpu
*preempt_notifier_to_vcpu(struct preempt_notifier
*pn
)
4627 return container_of(pn
, struct kvm_vcpu
, preempt_notifier
);
4630 static void kvm_sched_in(struct preempt_notifier
*pn
, int cpu
)
4632 struct kvm_vcpu
*vcpu
= preempt_notifier_to_vcpu(pn
);
4634 WRITE_ONCE(vcpu
->preempted
, false);
4635 WRITE_ONCE(vcpu
->ready
, false);
4637 __this_cpu_write(kvm_running_vcpu
, vcpu
);
4638 kvm_arch_sched_in(vcpu
, cpu
);
4639 kvm_arch_vcpu_load(vcpu
, cpu
);
4642 static void kvm_sched_out(struct preempt_notifier
*pn
,
4643 struct task_struct
*next
)
4645 struct kvm_vcpu
*vcpu
= preempt_notifier_to_vcpu(pn
);
4647 if (current
->state
== TASK_RUNNING
) {
4648 WRITE_ONCE(vcpu
->preempted
, true);
4649 WRITE_ONCE(vcpu
->ready
, true);
4651 kvm_arch_vcpu_put(vcpu
);
4652 __this_cpu_write(kvm_running_vcpu
, NULL
);
4656 * kvm_get_running_vcpu - get the vcpu running on the current CPU.
4658 * We can disable preemption locally around accessing the per-CPU variable,
4659 * and use the resolved vcpu pointer after enabling preemption again,
4660 * because even if the current thread is migrated to another CPU, reading
4661 * the per-CPU value later will give us the same value as we update the
4662 * per-CPU variable in the preempt notifier handlers.
4664 struct kvm_vcpu
*kvm_get_running_vcpu(void)
4666 struct kvm_vcpu
*vcpu
;
4669 vcpu
= __this_cpu_read(kvm_running_vcpu
);
4674 EXPORT_SYMBOL_GPL(kvm_get_running_vcpu
);
4677 * kvm_get_running_vcpus - get the per-CPU array of currently running vcpus.
4679 struct kvm_vcpu
* __percpu
*kvm_get_running_vcpus(void)
4681 return &kvm_running_vcpu
;
4684 struct kvm_cpu_compat_check
{
4689 static void check_processor_compat(void *data
)
4691 struct kvm_cpu_compat_check
*c
= data
;
4693 *c
->ret
= kvm_arch_check_processor_compat(c
->opaque
);
4696 int kvm_init(void *opaque
, unsigned vcpu_size
, unsigned vcpu_align
,
4697 struct module
*module
)
4699 struct kvm_cpu_compat_check c
;
4703 r
= kvm_arch_init(opaque
);
4708 * kvm_arch_init makes sure there's at most one caller
4709 * for architectures that support multiple implementations,
4710 * like intel and amd on x86.
4711 * kvm_arch_init must be called before kvm_irqfd_init to avoid creating
4712 * conflicts in case kvm is already setup for another implementation.
4714 r
= kvm_irqfd_init();
4718 if (!zalloc_cpumask_var(&cpus_hardware_enabled
, GFP_KERNEL
)) {
4723 r
= kvm_arch_hardware_setup(opaque
);
4729 for_each_online_cpu(cpu
) {
4730 smp_call_function_single(cpu
, check_processor_compat
, &c
, 1);
4735 r
= cpuhp_setup_state_nocalls(CPUHP_AP_KVM_STARTING
, "kvm/cpu:starting",
4736 kvm_starting_cpu
, kvm_dying_cpu
);
4739 register_reboot_notifier(&kvm_reboot_notifier
);
4741 /* A kmem cache lets us meet the alignment requirements of fx_save. */
4743 vcpu_align
= __alignof__(struct kvm_vcpu
);
4745 kmem_cache_create_usercopy("kvm_vcpu", vcpu_size
, vcpu_align
,
4747 offsetof(struct kvm_vcpu
, arch
),
4748 sizeof_field(struct kvm_vcpu
, arch
),
4750 if (!kvm_vcpu_cache
) {
4755 r
= kvm_async_pf_init();
4759 kvm_chardev_ops
.owner
= module
;
4760 kvm_vm_fops
.owner
= module
;
4761 kvm_vcpu_fops
.owner
= module
;
4763 r
= misc_register(&kvm_dev
);
4765 pr_err("kvm: misc device register failed\n");
4769 register_syscore_ops(&kvm_syscore_ops
);
4771 kvm_preempt_ops
.sched_in
= kvm_sched_in
;
4772 kvm_preempt_ops
.sched_out
= kvm_sched_out
;
4776 r
= kvm_vfio_ops_init();
4782 kvm_async_pf_deinit();
4784 kmem_cache_destroy(kvm_vcpu_cache
);
4786 unregister_reboot_notifier(&kvm_reboot_notifier
);
4787 cpuhp_remove_state_nocalls(CPUHP_AP_KVM_STARTING
);
4789 kvm_arch_hardware_unsetup();
4791 free_cpumask_var(cpus_hardware_enabled
);
4799 EXPORT_SYMBOL_GPL(kvm_init
);
4803 debugfs_remove_recursive(kvm_debugfs_dir
);
4804 misc_deregister(&kvm_dev
);
4805 kmem_cache_destroy(kvm_vcpu_cache
);
4806 kvm_async_pf_deinit();
4807 unregister_syscore_ops(&kvm_syscore_ops
);
4808 unregister_reboot_notifier(&kvm_reboot_notifier
);
4809 cpuhp_remove_state_nocalls(CPUHP_AP_KVM_STARTING
);
4810 on_each_cpu(hardware_disable_nolock
, NULL
, 1);
4811 kvm_arch_hardware_unsetup();
4814 free_cpumask_var(cpus_hardware_enabled
);
4815 kvm_vfio_ops_exit();
4817 EXPORT_SYMBOL_GPL(kvm_exit
);
4819 struct kvm_vm_worker_thread_context
{
4821 struct task_struct
*parent
;
4822 struct completion init_done
;
4823 kvm_vm_thread_fn_t thread_fn
;
4828 static int kvm_vm_worker_thread(void *context
)
4831 * The init_context is allocated on the stack of the parent thread, so
4832 * we have to locally copy anything that is needed beyond initialization
4834 struct kvm_vm_worker_thread_context
*init_context
= context
;
4835 struct kvm
*kvm
= init_context
->kvm
;
4836 kvm_vm_thread_fn_t thread_fn
= init_context
->thread_fn
;
4837 uintptr_t data
= init_context
->data
;
4840 err
= kthread_park(current
);
4841 /* kthread_park(current) is never supposed to return an error */
4846 err
= cgroup_attach_task_all(init_context
->parent
, current
);
4848 kvm_err("%s: cgroup_attach_task_all failed with err %d\n",
4853 set_user_nice(current
, task_nice(init_context
->parent
));
4856 init_context
->err
= err
;
4857 complete(&init_context
->init_done
);
4858 init_context
= NULL
;
4863 /* Wait to be woken up by the spawner before proceeding. */
4866 if (!kthread_should_stop())
4867 err
= thread_fn(kvm
, data
);
4872 int kvm_vm_create_worker_thread(struct kvm
*kvm
, kvm_vm_thread_fn_t thread_fn
,
4873 uintptr_t data
, const char *name
,
4874 struct task_struct
**thread_ptr
)
4876 struct kvm_vm_worker_thread_context init_context
= {};
4877 struct task_struct
*thread
;
4880 init_context
.kvm
= kvm
;
4881 init_context
.parent
= current
;
4882 init_context
.thread_fn
= thread_fn
;
4883 init_context
.data
= data
;
4884 init_completion(&init_context
.init_done
);
4886 thread
= kthread_run(kvm_vm_worker_thread
, &init_context
,
4887 "%s-%d", name
, task_pid_nr(current
));
4889 return PTR_ERR(thread
);
4891 /* kthread_run is never supposed to return NULL */
4892 WARN_ON(thread
== NULL
);
4894 wait_for_completion(&init_context
.init_done
);
4896 if (!init_context
.err
)
4897 *thread_ptr
= thread
;
4899 return init_context
.err
;