2 * Kernel-based Virtual Machine driver for Linux
4 * This module enables machines with Intel VT-x extensions to run virtual
5 * machines without emulation or binary translation.
7 * Copyright (C) 2006 Qumranet, Inc.
8 * Copyright 2010 Red Hat, Inc. and/or its affiliates.
11 * Avi Kivity <avi@qumranet.com>
12 * Yaniv Kamay <yaniv@qumranet.com>
14 * This work is licensed under the terms of the GNU GPL, version 2. See
15 * the COPYING file in the top-level directory.
19 #include <kvm/iodev.h>
21 #include <linux/kvm_host.h>
22 #include <linux/kvm.h>
23 #include <linux/module.h>
24 #include <linux/errno.h>
25 #include <linux/percpu.h>
27 #include <linux/miscdevice.h>
28 #include <linux/vmalloc.h>
29 #include <linux/reboot.h>
30 #include <linux/debugfs.h>
31 #include <linux/highmem.h>
32 #include <linux/file.h>
33 #include <linux/syscore_ops.h>
34 #include <linux/cpu.h>
35 #include <linux/sched.h>
36 #include <linux/cpumask.h>
37 #include <linux/smp.h>
38 #include <linux/anon_inodes.h>
39 #include <linux/profile.h>
40 #include <linux/kvm_para.h>
41 #include <linux/pagemap.h>
42 #include <linux/mman.h>
43 #include <linux/swap.h>
44 #include <linux/bitops.h>
45 #include <linux/spinlock.h>
46 #include <linux/compat.h>
47 #include <linux/srcu.h>
48 #include <linux/hugetlb.h>
49 #include <linux/slab.h>
50 #include <linux/sort.h>
51 #include <linux/bsearch.h>
53 #include <asm/processor.h>
55 #include <asm/ioctl.h>
56 #include <asm/uaccess.h>
57 #include <asm/pgtable.h>
59 #include "coalesced_mmio.h"
63 #define CREATE_TRACE_POINTS
64 #include <trace/events/kvm.h>
66 /* Worst case buffer size needed for holding an integer. */
67 #define ITOA_MAX_LEN 12
69 MODULE_AUTHOR("Qumranet");
70 MODULE_LICENSE("GPL");
72 /* Architectures should define their poll value according to the halt latency */
73 static unsigned int halt_poll_ns
= KVM_HALT_POLL_NS_DEFAULT
;
74 module_param(halt_poll_ns
, uint
, S_IRUGO
| S_IWUSR
);
76 /* Default doubles per-vcpu halt_poll_ns. */
77 static unsigned int halt_poll_ns_grow
= 2;
78 module_param(halt_poll_ns_grow
, uint
, S_IRUGO
| S_IWUSR
);
80 /* Default resets per-vcpu halt_poll_ns . */
81 static unsigned int halt_poll_ns_shrink
;
82 module_param(halt_poll_ns_shrink
, uint
, S_IRUGO
| S_IWUSR
);
87 * kvm->lock --> kvm->slots_lock --> kvm->irq_lock
90 DEFINE_SPINLOCK(kvm_lock
);
91 static DEFINE_RAW_SPINLOCK(kvm_count_lock
);
94 static cpumask_var_t cpus_hardware_enabled
;
95 static int kvm_usage_count
;
96 static atomic_t hardware_enable_failed
;
98 struct kmem_cache
*kvm_vcpu_cache
;
99 EXPORT_SYMBOL_GPL(kvm_vcpu_cache
);
101 static __read_mostly
struct preempt_ops kvm_preempt_ops
;
103 struct dentry
*kvm_debugfs_dir
;
104 EXPORT_SYMBOL_GPL(kvm_debugfs_dir
);
106 static int kvm_debugfs_num_entries
;
107 static const struct file_operations
*stat_fops_per_vm
[];
109 static long kvm_vcpu_ioctl(struct file
*file
, unsigned int ioctl
,
111 #ifdef CONFIG_KVM_COMPAT
112 static long kvm_vcpu_compat_ioctl(struct file
*file
, unsigned int ioctl
,
115 static int hardware_enable_all(void);
116 static void hardware_disable_all(void);
118 static void kvm_io_bus_destroy(struct kvm_io_bus
*bus
);
120 static void kvm_release_pfn_dirty(kvm_pfn_t pfn
);
121 static void mark_page_dirty_in_slot(struct kvm_memory_slot
*memslot
, gfn_t gfn
);
123 __visible
bool kvm_rebooting
;
124 EXPORT_SYMBOL_GPL(kvm_rebooting
);
126 static bool largepages_enabled
= true;
128 bool kvm_is_reserved_pfn(kvm_pfn_t pfn
)
131 return PageReserved(pfn_to_page(pfn
));
137 * Switches to specified vcpu, until a matching vcpu_put()
139 int vcpu_load(struct kvm_vcpu
*vcpu
)
143 if (mutex_lock_killable(&vcpu
->mutex
))
146 preempt_notifier_register(&vcpu
->preempt_notifier
);
147 kvm_arch_vcpu_load(vcpu
, cpu
);
151 EXPORT_SYMBOL_GPL(vcpu_load
);
153 void vcpu_put(struct kvm_vcpu
*vcpu
)
156 kvm_arch_vcpu_put(vcpu
);
157 preempt_notifier_unregister(&vcpu
->preempt_notifier
);
159 mutex_unlock(&vcpu
->mutex
);
161 EXPORT_SYMBOL_GPL(vcpu_put
);
163 static void ack_flush(void *_completed
)
167 bool kvm_make_all_cpus_request(struct kvm
*kvm
, unsigned int req
)
172 struct kvm_vcpu
*vcpu
;
174 zalloc_cpumask_var(&cpus
, GFP_ATOMIC
);
177 kvm_for_each_vcpu(i
, vcpu
, kvm
) {
178 kvm_make_request(req
, vcpu
);
181 /* Set ->requests bit before we read ->mode. */
182 smp_mb__after_atomic();
184 if (cpus
!= NULL
&& cpu
!= -1 && cpu
!= me
&&
185 kvm_vcpu_exiting_guest_mode(vcpu
) != OUTSIDE_GUEST_MODE
)
186 cpumask_set_cpu(cpu
, cpus
);
188 if (unlikely(cpus
== NULL
))
189 smp_call_function_many(cpu_online_mask
, ack_flush
, NULL
, 1);
190 else if (!cpumask_empty(cpus
))
191 smp_call_function_many(cpus
, ack_flush
, NULL
, 1);
195 free_cpumask_var(cpus
);
199 #ifndef CONFIG_HAVE_KVM_ARCH_TLB_FLUSH_ALL
200 void kvm_flush_remote_tlbs(struct kvm
*kvm
)
203 * Read tlbs_dirty before setting KVM_REQ_TLB_FLUSH in
204 * kvm_make_all_cpus_request.
206 long dirty_count
= smp_load_acquire(&kvm
->tlbs_dirty
);
209 * We want to publish modifications to the page tables before reading
210 * mode. Pairs with a memory barrier in arch-specific code.
211 * - x86: smp_mb__after_srcu_read_unlock in vcpu_enter_guest
212 * and smp_mb in walk_shadow_page_lockless_begin/end.
213 * - powerpc: smp_mb in kvmppc_prepare_to_enter.
215 * There is already an smp_mb__after_atomic() before
216 * kvm_make_all_cpus_request() reads vcpu->mode. We reuse that
219 if (kvm_make_all_cpus_request(kvm
, KVM_REQ_TLB_FLUSH
))
220 ++kvm
->stat
.remote_tlb_flush
;
221 cmpxchg(&kvm
->tlbs_dirty
, dirty_count
, 0);
223 EXPORT_SYMBOL_GPL(kvm_flush_remote_tlbs
);
226 void kvm_reload_remote_mmus(struct kvm
*kvm
)
228 kvm_make_all_cpus_request(kvm
, KVM_REQ_MMU_RELOAD
);
231 int kvm_vcpu_init(struct kvm_vcpu
*vcpu
, struct kvm
*kvm
, unsigned id
)
236 mutex_init(&vcpu
->mutex
);
241 init_swait_queue_head(&vcpu
->wq
);
242 kvm_async_pf_vcpu_init(vcpu
);
245 INIT_LIST_HEAD(&vcpu
->blocked_vcpu_list
);
247 page
= alloc_page(GFP_KERNEL
| __GFP_ZERO
);
252 vcpu
->run
= page_address(page
);
254 kvm_vcpu_set_in_spin_loop(vcpu
, false);
255 kvm_vcpu_set_dy_eligible(vcpu
, false);
256 vcpu
->preempted
= false;
258 r
= kvm_arch_vcpu_init(vcpu
);
264 free_page((unsigned long)vcpu
->run
);
268 EXPORT_SYMBOL_GPL(kvm_vcpu_init
);
270 void kvm_vcpu_uninit(struct kvm_vcpu
*vcpu
)
273 kvm_arch_vcpu_uninit(vcpu
);
274 free_page((unsigned long)vcpu
->run
);
276 EXPORT_SYMBOL_GPL(kvm_vcpu_uninit
);
278 #if defined(CONFIG_MMU_NOTIFIER) && defined(KVM_ARCH_WANT_MMU_NOTIFIER)
279 static inline struct kvm
*mmu_notifier_to_kvm(struct mmu_notifier
*mn
)
281 return container_of(mn
, struct kvm
, mmu_notifier
);
284 static void kvm_mmu_notifier_invalidate_page(struct mmu_notifier
*mn
,
285 struct mm_struct
*mm
,
286 unsigned long address
)
288 struct kvm
*kvm
= mmu_notifier_to_kvm(mn
);
289 int need_tlb_flush
, idx
;
292 * When ->invalidate_page runs, the linux pte has been zapped
293 * already but the page is still allocated until
294 * ->invalidate_page returns. So if we increase the sequence
295 * here the kvm page fault will notice if the spte can't be
296 * established because the page is going to be freed. If
297 * instead the kvm page fault establishes the spte before
298 * ->invalidate_page runs, kvm_unmap_hva will release it
301 * The sequence increase only need to be seen at spin_unlock
302 * time, and not at spin_lock time.
304 * Increasing the sequence after the spin_unlock would be
305 * unsafe because the kvm page fault could then establish the
306 * pte after kvm_unmap_hva returned, without noticing the page
307 * is going to be freed.
309 idx
= srcu_read_lock(&kvm
->srcu
);
310 spin_lock(&kvm
->mmu_lock
);
312 kvm
->mmu_notifier_seq
++;
313 need_tlb_flush
= kvm_unmap_hva(kvm
, address
) | kvm
->tlbs_dirty
;
314 /* we've to flush the tlb before the pages can be freed */
316 kvm_flush_remote_tlbs(kvm
);
318 spin_unlock(&kvm
->mmu_lock
);
320 kvm_arch_mmu_notifier_invalidate_page(kvm
, address
);
322 srcu_read_unlock(&kvm
->srcu
, idx
);
325 static void kvm_mmu_notifier_change_pte(struct mmu_notifier
*mn
,
326 struct mm_struct
*mm
,
327 unsigned long address
,
330 struct kvm
*kvm
= mmu_notifier_to_kvm(mn
);
333 idx
= srcu_read_lock(&kvm
->srcu
);
334 spin_lock(&kvm
->mmu_lock
);
335 kvm
->mmu_notifier_seq
++;
336 kvm_set_spte_hva(kvm
, address
, pte
);
337 spin_unlock(&kvm
->mmu_lock
);
338 srcu_read_unlock(&kvm
->srcu
, idx
);
341 static void kvm_mmu_notifier_invalidate_range_start(struct mmu_notifier
*mn
,
342 struct mm_struct
*mm
,
346 struct kvm
*kvm
= mmu_notifier_to_kvm(mn
);
347 int need_tlb_flush
= 0, idx
;
349 idx
= srcu_read_lock(&kvm
->srcu
);
350 spin_lock(&kvm
->mmu_lock
);
352 * The count increase must become visible at unlock time as no
353 * spte can be established without taking the mmu_lock and
354 * count is also read inside the mmu_lock critical section.
356 kvm
->mmu_notifier_count
++;
357 need_tlb_flush
= kvm_unmap_hva_range(kvm
, start
, end
);
358 need_tlb_flush
|= kvm
->tlbs_dirty
;
359 /* we've to flush the tlb before the pages can be freed */
361 kvm_flush_remote_tlbs(kvm
);
363 spin_unlock(&kvm
->mmu_lock
);
364 srcu_read_unlock(&kvm
->srcu
, idx
);
367 static void kvm_mmu_notifier_invalidate_range_end(struct mmu_notifier
*mn
,
368 struct mm_struct
*mm
,
372 struct kvm
*kvm
= mmu_notifier_to_kvm(mn
);
374 spin_lock(&kvm
->mmu_lock
);
376 * This sequence increase will notify the kvm page fault that
377 * the page that is going to be mapped in the spte could have
380 kvm
->mmu_notifier_seq
++;
383 * The above sequence increase must be visible before the
384 * below count decrease, which is ensured by the smp_wmb above
385 * in conjunction with the smp_rmb in mmu_notifier_retry().
387 kvm
->mmu_notifier_count
--;
388 spin_unlock(&kvm
->mmu_lock
);
390 BUG_ON(kvm
->mmu_notifier_count
< 0);
393 static int kvm_mmu_notifier_clear_flush_young(struct mmu_notifier
*mn
,
394 struct mm_struct
*mm
,
398 struct kvm
*kvm
= mmu_notifier_to_kvm(mn
);
401 idx
= srcu_read_lock(&kvm
->srcu
);
402 spin_lock(&kvm
->mmu_lock
);
404 young
= kvm_age_hva(kvm
, start
, end
);
406 kvm_flush_remote_tlbs(kvm
);
408 spin_unlock(&kvm
->mmu_lock
);
409 srcu_read_unlock(&kvm
->srcu
, idx
);
414 static int kvm_mmu_notifier_clear_young(struct mmu_notifier
*mn
,
415 struct mm_struct
*mm
,
419 struct kvm
*kvm
= mmu_notifier_to_kvm(mn
);
422 idx
= srcu_read_lock(&kvm
->srcu
);
423 spin_lock(&kvm
->mmu_lock
);
425 * Even though we do not flush TLB, this will still adversely
426 * affect performance on pre-Haswell Intel EPT, where there is
427 * no EPT Access Bit to clear so that we have to tear down EPT
428 * tables instead. If we find this unacceptable, we can always
429 * add a parameter to kvm_age_hva so that it effectively doesn't
430 * do anything on clear_young.
432 * Also note that currently we never issue secondary TLB flushes
433 * from clear_young, leaving this job up to the regular system
434 * cadence. If we find this inaccurate, we might come up with a
435 * more sophisticated heuristic later.
437 young
= kvm_age_hva(kvm
, start
, end
);
438 spin_unlock(&kvm
->mmu_lock
);
439 srcu_read_unlock(&kvm
->srcu
, idx
);
444 static int kvm_mmu_notifier_test_young(struct mmu_notifier
*mn
,
445 struct mm_struct
*mm
,
446 unsigned long address
)
448 struct kvm
*kvm
= mmu_notifier_to_kvm(mn
);
451 idx
= srcu_read_lock(&kvm
->srcu
);
452 spin_lock(&kvm
->mmu_lock
);
453 young
= kvm_test_age_hva(kvm
, address
);
454 spin_unlock(&kvm
->mmu_lock
);
455 srcu_read_unlock(&kvm
->srcu
, idx
);
460 static void kvm_mmu_notifier_release(struct mmu_notifier
*mn
,
461 struct mm_struct
*mm
)
463 struct kvm
*kvm
= mmu_notifier_to_kvm(mn
);
466 idx
= srcu_read_lock(&kvm
->srcu
);
467 kvm_arch_flush_shadow_all(kvm
);
468 srcu_read_unlock(&kvm
->srcu
, idx
);
471 static const struct mmu_notifier_ops kvm_mmu_notifier_ops
= {
472 .invalidate_page
= kvm_mmu_notifier_invalidate_page
,
473 .invalidate_range_start
= kvm_mmu_notifier_invalidate_range_start
,
474 .invalidate_range_end
= kvm_mmu_notifier_invalidate_range_end
,
475 .clear_flush_young
= kvm_mmu_notifier_clear_flush_young
,
476 .clear_young
= kvm_mmu_notifier_clear_young
,
477 .test_young
= kvm_mmu_notifier_test_young
,
478 .change_pte
= kvm_mmu_notifier_change_pte
,
479 .release
= kvm_mmu_notifier_release
,
482 static int kvm_init_mmu_notifier(struct kvm
*kvm
)
484 kvm
->mmu_notifier
.ops
= &kvm_mmu_notifier_ops
;
485 return mmu_notifier_register(&kvm
->mmu_notifier
, current
->mm
);
488 #else /* !(CONFIG_MMU_NOTIFIER && KVM_ARCH_WANT_MMU_NOTIFIER) */
490 static int kvm_init_mmu_notifier(struct kvm
*kvm
)
495 #endif /* CONFIG_MMU_NOTIFIER && KVM_ARCH_WANT_MMU_NOTIFIER */
497 static struct kvm_memslots
*kvm_alloc_memslots(void)
500 struct kvm_memslots
*slots
;
502 slots
= kvm_kvzalloc(sizeof(struct kvm_memslots
));
507 * Init kvm generation close to the maximum to easily test the
508 * code of handling generation number wrap-around.
510 slots
->generation
= -150;
511 for (i
= 0; i
< KVM_MEM_SLOTS_NUM
; i
++)
512 slots
->id_to_index
[i
] = slots
->memslots
[i
].id
= i
;
517 static void kvm_destroy_dirty_bitmap(struct kvm_memory_slot
*memslot
)
519 if (!memslot
->dirty_bitmap
)
522 kvfree(memslot
->dirty_bitmap
);
523 memslot
->dirty_bitmap
= NULL
;
527 * Free any memory in @free but not in @dont.
529 static void kvm_free_memslot(struct kvm
*kvm
, struct kvm_memory_slot
*free
,
530 struct kvm_memory_slot
*dont
)
532 if (!dont
|| free
->dirty_bitmap
!= dont
->dirty_bitmap
)
533 kvm_destroy_dirty_bitmap(free
);
535 kvm_arch_free_memslot(kvm
, free
, dont
);
540 static void kvm_free_memslots(struct kvm
*kvm
, struct kvm_memslots
*slots
)
542 struct kvm_memory_slot
*memslot
;
547 kvm_for_each_memslot(memslot
, slots
)
548 kvm_free_memslot(kvm
, memslot
, NULL
);
553 static void kvm_destroy_vm_debugfs(struct kvm
*kvm
)
557 if (!kvm
->debugfs_dentry
)
560 debugfs_remove_recursive(kvm
->debugfs_dentry
);
562 if (kvm
->debugfs_stat_data
) {
563 for (i
= 0; i
< kvm_debugfs_num_entries
; i
++)
564 kfree(kvm
->debugfs_stat_data
[i
]);
565 kfree(kvm
->debugfs_stat_data
);
569 static int kvm_create_vm_debugfs(struct kvm
*kvm
, int fd
)
571 char dir_name
[ITOA_MAX_LEN
* 2];
572 struct kvm_stat_data
*stat_data
;
573 struct kvm_stats_debugfs_item
*p
;
575 if (!debugfs_initialized())
578 snprintf(dir_name
, sizeof(dir_name
), "%d-%d", task_pid_nr(current
), fd
);
579 kvm
->debugfs_dentry
= debugfs_create_dir(dir_name
,
581 if (!kvm
->debugfs_dentry
)
584 kvm
->debugfs_stat_data
= kcalloc(kvm_debugfs_num_entries
,
585 sizeof(*kvm
->debugfs_stat_data
),
587 if (!kvm
->debugfs_stat_data
)
590 for (p
= debugfs_entries
; p
->name
; p
++) {
591 stat_data
= kzalloc(sizeof(*stat_data
), GFP_KERNEL
);
595 stat_data
->kvm
= kvm
;
596 stat_data
->offset
= p
->offset
;
597 kvm
->debugfs_stat_data
[p
- debugfs_entries
] = stat_data
;
598 if (!debugfs_create_file(p
->name
, 0444,
601 stat_fops_per_vm
[p
->kind
]))
607 static struct kvm
*kvm_create_vm(unsigned long type
)
610 struct kvm
*kvm
= kvm_arch_alloc_vm();
613 return ERR_PTR(-ENOMEM
);
615 spin_lock_init(&kvm
->mmu_lock
);
616 atomic_inc(¤t
->mm
->mm_count
);
617 kvm
->mm
= current
->mm
;
618 kvm_eventfd_init(kvm
);
619 mutex_init(&kvm
->lock
);
620 mutex_init(&kvm
->irq_lock
);
621 mutex_init(&kvm
->slots_lock
);
622 atomic_set(&kvm
->users_count
, 1);
623 INIT_LIST_HEAD(&kvm
->devices
);
625 r
= kvm_arch_init_vm(kvm
, type
);
627 goto out_err_no_disable
;
629 r
= hardware_enable_all();
631 goto out_err_no_disable
;
633 #ifdef CONFIG_HAVE_KVM_IRQFD
634 INIT_HLIST_HEAD(&kvm
->irq_ack_notifier_list
);
637 BUILD_BUG_ON(KVM_MEM_SLOTS_NUM
> SHRT_MAX
);
640 for (i
= 0; i
< KVM_ADDRESS_SPACE_NUM
; i
++) {
641 kvm
->memslots
[i
] = kvm_alloc_memslots();
642 if (!kvm
->memslots
[i
])
643 goto out_err_no_srcu
;
646 if (init_srcu_struct(&kvm
->srcu
))
647 goto out_err_no_srcu
;
648 if (init_srcu_struct(&kvm
->irq_srcu
))
649 goto out_err_no_irq_srcu
;
650 for (i
= 0; i
< KVM_NR_BUSES
; i
++) {
651 kvm
->buses
[i
] = kzalloc(sizeof(struct kvm_io_bus
),
657 r
= kvm_init_mmu_notifier(kvm
);
661 spin_lock(&kvm_lock
);
662 list_add(&kvm
->vm_list
, &vm_list
);
663 spin_unlock(&kvm_lock
);
665 preempt_notifier_inc();
670 cleanup_srcu_struct(&kvm
->irq_srcu
);
672 cleanup_srcu_struct(&kvm
->srcu
);
674 hardware_disable_all();
676 for (i
= 0; i
< KVM_NR_BUSES
; i
++)
677 kfree(kvm
->buses
[i
]);
678 for (i
= 0; i
< KVM_ADDRESS_SPACE_NUM
; i
++)
679 kvm_free_memslots(kvm
, kvm
->memslots
[i
]);
680 kvm_arch_free_vm(kvm
);
686 * Avoid using vmalloc for a small buffer.
687 * Should not be used when the size is statically known.
689 void *kvm_kvzalloc(unsigned long size
)
691 if (size
> PAGE_SIZE
)
692 return vzalloc(size
);
694 return kzalloc(size
, GFP_KERNEL
);
697 static void kvm_destroy_devices(struct kvm
*kvm
)
699 struct kvm_device
*dev
, *tmp
;
702 * We do not need to take the kvm->lock here, because nobody else
703 * has a reference to the struct kvm at this point and therefore
704 * cannot access the devices list anyhow.
706 list_for_each_entry_safe(dev
, tmp
, &kvm
->devices
, vm_node
) {
707 list_del(&dev
->vm_node
);
708 dev
->ops
->destroy(dev
);
712 static void kvm_destroy_vm(struct kvm
*kvm
)
715 struct mm_struct
*mm
= kvm
->mm
;
717 kvm_destroy_vm_debugfs(kvm
);
718 kvm_arch_sync_events(kvm
);
719 spin_lock(&kvm_lock
);
720 list_del(&kvm
->vm_list
);
721 spin_unlock(&kvm_lock
);
722 kvm_free_irq_routing(kvm
);
723 for (i
= 0; i
< KVM_NR_BUSES
; i
++)
724 kvm_io_bus_destroy(kvm
->buses
[i
]);
725 kvm_coalesced_mmio_free(kvm
);
726 #if defined(CONFIG_MMU_NOTIFIER) && defined(KVM_ARCH_WANT_MMU_NOTIFIER)
727 mmu_notifier_unregister(&kvm
->mmu_notifier
, kvm
->mm
);
729 kvm_arch_flush_shadow_all(kvm
);
731 kvm_arch_destroy_vm(kvm
);
732 kvm_destroy_devices(kvm
);
733 for (i
= 0; i
< KVM_ADDRESS_SPACE_NUM
; i
++)
734 kvm_free_memslots(kvm
, kvm
->memslots
[i
]);
735 cleanup_srcu_struct(&kvm
->irq_srcu
);
736 cleanup_srcu_struct(&kvm
->srcu
);
737 kvm_arch_free_vm(kvm
);
738 preempt_notifier_dec();
739 hardware_disable_all();
743 void kvm_get_kvm(struct kvm
*kvm
)
745 atomic_inc(&kvm
->users_count
);
747 EXPORT_SYMBOL_GPL(kvm_get_kvm
);
749 void kvm_put_kvm(struct kvm
*kvm
)
751 if (atomic_dec_and_test(&kvm
->users_count
))
754 EXPORT_SYMBOL_GPL(kvm_put_kvm
);
757 static int kvm_vm_release(struct inode
*inode
, struct file
*filp
)
759 struct kvm
*kvm
= filp
->private_data
;
761 kvm_irqfd_release(kvm
);
768 * Allocation size is twice as large as the actual dirty bitmap size.
769 * See x86's kvm_vm_ioctl_get_dirty_log() why this is needed.
771 static int kvm_create_dirty_bitmap(struct kvm_memory_slot
*memslot
)
773 unsigned long dirty_bytes
= 2 * kvm_dirty_bitmap_bytes(memslot
);
775 memslot
->dirty_bitmap
= kvm_kvzalloc(dirty_bytes
);
776 if (!memslot
->dirty_bitmap
)
783 * Insert memslot and re-sort memslots based on their GFN,
784 * so binary search could be used to lookup GFN.
785 * Sorting algorithm takes advantage of having initially
786 * sorted array and known changed memslot position.
788 static void update_memslots(struct kvm_memslots
*slots
,
789 struct kvm_memory_slot
*new)
792 int i
= slots
->id_to_index
[id
];
793 struct kvm_memory_slot
*mslots
= slots
->memslots
;
795 WARN_ON(mslots
[i
].id
!= id
);
797 WARN_ON(!mslots
[i
].npages
);
798 if (mslots
[i
].npages
)
801 if (!mslots
[i
].npages
)
805 while (i
< KVM_MEM_SLOTS_NUM
- 1 &&
806 new->base_gfn
<= mslots
[i
+ 1].base_gfn
) {
807 if (!mslots
[i
+ 1].npages
)
809 mslots
[i
] = mslots
[i
+ 1];
810 slots
->id_to_index
[mslots
[i
].id
] = i
;
815 * The ">=" is needed when creating a slot with base_gfn == 0,
816 * so that it moves before all those with base_gfn == npages == 0.
818 * On the other hand, if new->npages is zero, the above loop has
819 * already left i pointing to the beginning of the empty part of
820 * mslots, and the ">=" would move the hole backwards in this
821 * case---which is wrong. So skip the loop when deleting a slot.
825 new->base_gfn
>= mslots
[i
- 1].base_gfn
) {
826 mslots
[i
] = mslots
[i
- 1];
827 slots
->id_to_index
[mslots
[i
].id
] = i
;
831 WARN_ON_ONCE(i
!= slots
->used_slots
);
834 slots
->id_to_index
[mslots
[i
].id
] = i
;
837 static int check_memory_region_flags(const struct kvm_userspace_memory_region
*mem
)
839 u32 valid_flags
= KVM_MEM_LOG_DIRTY_PAGES
;
841 #ifdef __KVM_HAVE_READONLY_MEM
842 valid_flags
|= KVM_MEM_READONLY
;
845 if (mem
->flags
& ~valid_flags
)
851 static struct kvm_memslots
*install_new_memslots(struct kvm
*kvm
,
852 int as_id
, struct kvm_memslots
*slots
)
854 struct kvm_memslots
*old_memslots
= __kvm_memslots(kvm
, as_id
);
857 * Set the low bit in the generation, which disables SPTE caching
858 * until the end of synchronize_srcu_expedited.
860 WARN_ON(old_memslots
->generation
& 1);
861 slots
->generation
= old_memslots
->generation
+ 1;
863 rcu_assign_pointer(kvm
->memslots
[as_id
], slots
);
864 synchronize_srcu_expedited(&kvm
->srcu
);
867 * Increment the new memslot generation a second time. This prevents
868 * vm exits that race with memslot updates from caching a memslot
869 * generation that will (potentially) be valid forever.
873 kvm_arch_memslots_updated(kvm
, slots
);
879 * Allocate some memory and give it an address in the guest physical address
882 * Discontiguous memory is allowed, mostly for framebuffers.
884 * Must be called holding kvm->slots_lock for write.
886 int __kvm_set_memory_region(struct kvm
*kvm
,
887 const struct kvm_userspace_memory_region
*mem
)
891 unsigned long npages
;
892 struct kvm_memory_slot
*slot
;
893 struct kvm_memory_slot old
, new;
894 struct kvm_memslots
*slots
= NULL
, *old_memslots
;
896 enum kvm_mr_change change
;
898 r
= check_memory_region_flags(mem
);
903 as_id
= mem
->slot
>> 16;
906 /* General sanity checks */
907 if (mem
->memory_size
& (PAGE_SIZE
- 1))
909 if (mem
->guest_phys_addr
& (PAGE_SIZE
- 1))
911 /* We can read the guest memory with __xxx_user() later on. */
912 if ((id
< KVM_USER_MEM_SLOTS
) &&
913 ((mem
->userspace_addr
& (PAGE_SIZE
- 1)) ||
914 !access_ok(VERIFY_WRITE
,
915 (void __user
*)(unsigned long)mem
->userspace_addr
,
918 if (as_id
>= KVM_ADDRESS_SPACE_NUM
|| id
>= KVM_MEM_SLOTS_NUM
)
920 if (mem
->guest_phys_addr
+ mem
->memory_size
< mem
->guest_phys_addr
)
923 slot
= id_to_memslot(__kvm_memslots(kvm
, as_id
), id
);
924 base_gfn
= mem
->guest_phys_addr
>> PAGE_SHIFT
;
925 npages
= mem
->memory_size
>> PAGE_SHIFT
;
927 if (npages
> KVM_MEM_MAX_NR_PAGES
)
933 new.base_gfn
= base_gfn
;
935 new.flags
= mem
->flags
;
939 change
= KVM_MR_CREATE
;
940 else { /* Modify an existing slot. */
941 if ((mem
->userspace_addr
!= old
.userspace_addr
) ||
942 (npages
!= old
.npages
) ||
943 ((new.flags
^ old
.flags
) & KVM_MEM_READONLY
))
946 if (base_gfn
!= old
.base_gfn
)
947 change
= KVM_MR_MOVE
;
948 else if (new.flags
!= old
.flags
)
949 change
= KVM_MR_FLAGS_ONLY
;
950 else { /* Nothing to change. */
959 change
= KVM_MR_DELETE
;
964 if ((change
== KVM_MR_CREATE
) || (change
== KVM_MR_MOVE
)) {
965 /* Check for overlaps */
967 kvm_for_each_memslot(slot
, __kvm_memslots(kvm
, as_id
)) {
968 if ((slot
->id
>= KVM_USER_MEM_SLOTS
) ||
971 if (!((base_gfn
+ npages
<= slot
->base_gfn
) ||
972 (base_gfn
>= slot
->base_gfn
+ slot
->npages
)))
977 /* Free page dirty bitmap if unneeded */
978 if (!(new.flags
& KVM_MEM_LOG_DIRTY_PAGES
))
979 new.dirty_bitmap
= NULL
;
982 if (change
== KVM_MR_CREATE
) {
983 new.userspace_addr
= mem
->userspace_addr
;
985 if (kvm_arch_create_memslot(kvm
, &new, npages
))
989 /* Allocate page dirty bitmap if needed */
990 if ((new.flags
& KVM_MEM_LOG_DIRTY_PAGES
) && !new.dirty_bitmap
) {
991 if (kvm_create_dirty_bitmap(&new) < 0)
995 slots
= kvm_kvzalloc(sizeof(struct kvm_memslots
));
998 memcpy(slots
, __kvm_memslots(kvm
, as_id
), sizeof(struct kvm_memslots
));
1000 if ((change
== KVM_MR_DELETE
) || (change
== KVM_MR_MOVE
)) {
1001 slot
= id_to_memslot(slots
, id
);
1002 slot
->flags
|= KVM_MEMSLOT_INVALID
;
1004 old_memslots
= install_new_memslots(kvm
, as_id
, slots
);
1006 /* slot was deleted or moved, clear iommu mapping */
1007 kvm_iommu_unmap_pages(kvm
, &old
);
1008 /* From this point no new shadow pages pointing to a deleted,
1009 * or moved, memslot will be created.
1011 * validation of sp->gfn happens in:
1012 * - gfn_to_hva (kvm_read_guest, gfn_to_pfn)
1013 * - kvm_is_visible_gfn (mmu_check_roots)
1015 kvm_arch_flush_shadow_memslot(kvm
, slot
);
1018 * We can re-use the old_memslots from above, the only difference
1019 * from the currently installed memslots is the invalid flag. This
1020 * will get overwritten by update_memslots anyway.
1022 slots
= old_memslots
;
1025 r
= kvm_arch_prepare_memory_region(kvm
, &new, mem
, change
);
1029 /* actual memory is freed via old in kvm_free_memslot below */
1030 if (change
== KVM_MR_DELETE
) {
1031 new.dirty_bitmap
= NULL
;
1032 memset(&new.arch
, 0, sizeof(new.arch
));
1035 update_memslots(slots
, &new);
1036 old_memslots
= install_new_memslots(kvm
, as_id
, slots
);
1038 kvm_arch_commit_memory_region(kvm
, mem
, &old
, &new, change
);
1040 kvm_free_memslot(kvm
, &old
, &new);
1041 kvfree(old_memslots
);
1044 * IOMMU mapping: New slots need to be mapped. Old slots need to be
1045 * un-mapped and re-mapped if their base changes. Since base change
1046 * unmapping is handled above with slot deletion, mapping alone is
1047 * needed here. Anything else the iommu might care about for existing
1048 * slots (size changes, userspace addr changes and read-only flag
1049 * changes) is disallowed above, so any other attribute changes getting
1050 * here can be skipped.
1052 if ((change
== KVM_MR_CREATE
) || (change
== KVM_MR_MOVE
)) {
1053 r
= kvm_iommu_map_pages(kvm
, &new);
1062 kvm_free_memslot(kvm
, &new, &old
);
1066 EXPORT_SYMBOL_GPL(__kvm_set_memory_region
);
1068 int kvm_set_memory_region(struct kvm
*kvm
,
1069 const struct kvm_userspace_memory_region
*mem
)
1073 mutex_lock(&kvm
->slots_lock
);
1074 r
= __kvm_set_memory_region(kvm
, mem
);
1075 mutex_unlock(&kvm
->slots_lock
);
1078 EXPORT_SYMBOL_GPL(kvm_set_memory_region
);
1080 static int kvm_vm_ioctl_set_memory_region(struct kvm
*kvm
,
1081 struct kvm_userspace_memory_region
*mem
)
1083 if ((u16
)mem
->slot
>= KVM_USER_MEM_SLOTS
)
1086 return kvm_set_memory_region(kvm
, mem
);
1089 int kvm_get_dirty_log(struct kvm
*kvm
,
1090 struct kvm_dirty_log
*log
, int *is_dirty
)
1092 struct kvm_memslots
*slots
;
1093 struct kvm_memory_slot
*memslot
;
1094 int r
, i
, as_id
, id
;
1096 unsigned long any
= 0;
1099 as_id
= log
->slot
>> 16;
1100 id
= (u16
)log
->slot
;
1101 if (as_id
>= KVM_ADDRESS_SPACE_NUM
|| id
>= KVM_USER_MEM_SLOTS
)
1104 slots
= __kvm_memslots(kvm
, as_id
);
1105 memslot
= id_to_memslot(slots
, id
);
1107 if (!memslot
->dirty_bitmap
)
1110 n
= kvm_dirty_bitmap_bytes(memslot
);
1112 for (i
= 0; !any
&& i
< n
/sizeof(long); ++i
)
1113 any
= memslot
->dirty_bitmap
[i
];
1116 if (copy_to_user(log
->dirty_bitmap
, memslot
->dirty_bitmap
, n
))
1126 EXPORT_SYMBOL_GPL(kvm_get_dirty_log
);
1128 #ifdef CONFIG_KVM_GENERIC_DIRTYLOG_READ_PROTECT
1130 * kvm_get_dirty_log_protect - get a snapshot of dirty pages, and if any pages
1131 * are dirty write protect them for next write.
1132 * @kvm: pointer to kvm instance
1133 * @log: slot id and address to which we copy the log
1134 * @is_dirty: flag set if any page is dirty
1136 * We need to keep it in mind that VCPU threads can write to the bitmap
1137 * concurrently. So, to avoid losing track of dirty pages we keep the
1140 * 1. Take a snapshot of the bit and clear it if needed.
1141 * 2. Write protect the corresponding page.
1142 * 3. Copy the snapshot to the userspace.
1143 * 4. Upon return caller flushes TLB's if needed.
1145 * Between 2 and 4, the guest may write to the page using the remaining TLB
1146 * entry. This is not a problem because the page is reported dirty using
1147 * the snapshot taken before and step 4 ensures that writes done after
1148 * exiting to userspace will be logged for the next call.
1151 int kvm_get_dirty_log_protect(struct kvm
*kvm
,
1152 struct kvm_dirty_log
*log
, bool *is_dirty
)
1154 struct kvm_memslots
*slots
;
1155 struct kvm_memory_slot
*memslot
;
1156 int r
, i
, as_id
, id
;
1158 unsigned long *dirty_bitmap
;
1159 unsigned long *dirty_bitmap_buffer
;
1162 as_id
= log
->slot
>> 16;
1163 id
= (u16
)log
->slot
;
1164 if (as_id
>= KVM_ADDRESS_SPACE_NUM
|| id
>= KVM_USER_MEM_SLOTS
)
1167 slots
= __kvm_memslots(kvm
, as_id
);
1168 memslot
= id_to_memslot(slots
, id
);
1170 dirty_bitmap
= memslot
->dirty_bitmap
;
1175 n
= kvm_dirty_bitmap_bytes(memslot
);
1177 dirty_bitmap_buffer
= dirty_bitmap
+ n
/ sizeof(long);
1178 memset(dirty_bitmap_buffer
, 0, n
);
1180 spin_lock(&kvm
->mmu_lock
);
1182 for (i
= 0; i
< n
/ sizeof(long); i
++) {
1186 if (!dirty_bitmap
[i
])
1191 mask
= xchg(&dirty_bitmap
[i
], 0);
1192 dirty_bitmap_buffer
[i
] = mask
;
1195 offset
= i
* BITS_PER_LONG
;
1196 kvm_arch_mmu_enable_log_dirty_pt_masked(kvm
, memslot
,
1201 spin_unlock(&kvm
->mmu_lock
);
1204 if (copy_to_user(log
->dirty_bitmap
, dirty_bitmap_buffer
, n
))
1211 EXPORT_SYMBOL_GPL(kvm_get_dirty_log_protect
);
1214 bool kvm_largepages_enabled(void)
1216 return largepages_enabled
;
1219 void kvm_disable_largepages(void)
1221 largepages_enabled
= false;
1223 EXPORT_SYMBOL_GPL(kvm_disable_largepages
);
1225 struct kvm_memory_slot
*gfn_to_memslot(struct kvm
*kvm
, gfn_t gfn
)
1227 return __gfn_to_memslot(kvm_memslots(kvm
), gfn
);
1229 EXPORT_SYMBOL_GPL(gfn_to_memslot
);
1231 struct kvm_memory_slot
*kvm_vcpu_gfn_to_memslot(struct kvm_vcpu
*vcpu
, gfn_t gfn
)
1233 return __gfn_to_memslot(kvm_vcpu_memslots(vcpu
), gfn
);
1236 bool kvm_is_visible_gfn(struct kvm
*kvm
, gfn_t gfn
)
1238 struct kvm_memory_slot
*memslot
= gfn_to_memslot(kvm
, gfn
);
1240 if (!memslot
|| memslot
->id
>= KVM_USER_MEM_SLOTS
||
1241 memslot
->flags
& KVM_MEMSLOT_INVALID
)
1246 EXPORT_SYMBOL_GPL(kvm_is_visible_gfn
);
1248 unsigned long kvm_host_page_size(struct kvm
*kvm
, gfn_t gfn
)
1250 struct vm_area_struct
*vma
;
1251 unsigned long addr
, size
;
1255 addr
= gfn_to_hva(kvm
, gfn
);
1256 if (kvm_is_error_hva(addr
))
1259 down_read(¤t
->mm
->mmap_sem
);
1260 vma
= find_vma(current
->mm
, addr
);
1264 size
= vma_kernel_pagesize(vma
);
1267 up_read(¤t
->mm
->mmap_sem
);
1272 static bool memslot_is_readonly(struct kvm_memory_slot
*slot
)
1274 return slot
->flags
& KVM_MEM_READONLY
;
1277 static unsigned long __gfn_to_hva_many(struct kvm_memory_slot
*slot
, gfn_t gfn
,
1278 gfn_t
*nr_pages
, bool write
)
1280 if (!slot
|| slot
->flags
& KVM_MEMSLOT_INVALID
)
1281 return KVM_HVA_ERR_BAD
;
1283 if (memslot_is_readonly(slot
) && write
)
1284 return KVM_HVA_ERR_RO_BAD
;
1287 *nr_pages
= slot
->npages
- (gfn
- slot
->base_gfn
);
1289 return __gfn_to_hva_memslot(slot
, gfn
);
1292 static unsigned long gfn_to_hva_many(struct kvm_memory_slot
*slot
, gfn_t gfn
,
1295 return __gfn_to_hva_many(slot
, gfn
, nr_pages
, true);
1298 unsigned long gfn_to_hva_memslot(struct kvm_memory_slot
*slot
,
1301 return gfn_to_hva_many(slot
, gfn
, NULL
);
1303 EXPORT_SYMBOL_GPL(gfn_to_hva_memslot
);
1305 unsigned long gfn_to_hva(struct kvm
*kvm
, gfn_t gfn
)
1307 return gfn_to_hva_many(gfn_to_memslot(kvm
, gfn
), gfn
, NULL
);
1309 EXPORT_SYMBOL_GPL(gfn_to_hva
);
1311 unsigned long kvm_vcpu_gfn_to_hva(struct kvm_vcpu
*vcpu
, gfn_t gfn
)
1313 return gfn_to_hva_many(kvm_vcpu_gfn_to_memslot(vcpu
, gfn
), gfn
, NULL
);
1315 EXPORT_SYMBOL_GPL(kvm_vcpu_gfn_to_hva
);
1318 * If writable is set to false, the hva returned by this function is only
1319 * allowed to be read.
1321 unsigned long gfn_to_hva_memslot_prot(struct kvm_memory_slot
*slot
,
1322 gfn_t gfn
, bool *writable
)
1324 unsigned long hva
= __gfn_to_hva_many(slot
, gfn
, NULL
, false);
1326 if (!kvm_is_error_hva(hva
) && writable
)
1327 *writable
= !memslot_is_readonly(slot
);
1332 unsigned long gfn_to_hva_prot(struct kvm
*kvm
, gfn_t gfn
, bool *writable
)
1334 struct kvm_memory_slot
*slot
= gfn_to_memslot(kvm
, gfn
);
1336 return gfn_to_hva_memslot_prot(slot
, gfn
, writable
);
1339 unsigned long kvm_vcpu_gfn_to_hva_prot(struct kvm_vcpu
*vcpu
, gfn_t gfn
, bool *writable
)
1341 struct kvm_memory_slot
*slot
= kvm_vcpu_gfn_to_memslot(vcpu
, gfn
);
1343 return gfn_to_hva_memslot_prot(slot
, gfn
, writable
);
1346 static int get_user_page_nowait(unsigned long start
, int write
,
1349 int flags
= FOLL_TOUCH
| FOLL_NOWAIT
| FOLL_HWPOISON
| FOLL_GET
;
1352 flags
|= FOLL_WRITE
;
1354 return __get_user_pages(current
, current
->mm
, start
, 1, flags
, page
,
1358 static inline int check_user_page_hwpoison(unsigned long addr
)
1360 int rc
, flags
= FOLL_TOUCH
| FOLL_HWPOISON
| FOLL_WRITE
;
1362 rc
= __get_user_pages(current
, current
->mm
, addr
, 1,
1363 flags
, NULL
, NULL
, NULL
);
1364 return rc
== -EHWPOISON
;
1368 * The atomic path to get the writable pfn which will be stored in @pfn,
1369 * true indicates success, otherwise false is returned.
1371 static bool hva_to_pfn_fast(unsigned long addr
, bool atomic
, bool *async
,
1372 bool write_fault
, bool *writable
, kvm_pfn_t
*pfn
)
1374 struct page
*page
[1];
1377 if (!(async
|| atomic
))
1381 * Fast pin a writable pfn only if it is a write fault request
1382 * or the caller allows to map a writable pfn for a read fault
1385 if (!(write_fault
|| writable
))
1388 npages
= __get_user_pages_fast(addr
, 1, 1, page
);
1390 *pfn
= page_to_pfn(page
[0]);
1401 * The slow path to get the pfn of the specified host virtual address,
1402 * 1 indicates success, -errno is returned if error is detected.
1404 static int hva_to_pfn_slow(unsigned long addr
, bool *async
, bool write_fault
,
1405 bool *writable
, kvm_pfn_t
*pfn
)
1407 struct page
*page
[1];
1413 *writable
= write_fault
;
1416 down_read(¤t
->mm
->mmap_sem
);
1417 npages
= get_user_page_nowait(addr
, write_fault
, page
);
1418 up_read(¤t
->mm
->mmap_sem
);
1420 unsigned int flags
= FOLL_TOUCH
| FOLL_HWPOISON
;
1423 flags
|= FOLL_WRITE
;
1425 npages
= __get_user_pages_unlocked(current
, current
->mm
, addr
, 1,
1431 /* map read fault as writable if possible */
1432 if (unlikely(!write_fault
) && writable
) {
1433 struct page
*wpage
[1];
1435 npages
= __get_user_pages_fast(addr
, 1, 1, wpage
);
1444 *pfn
= page_to_pfn(page
[0]);
1448 static bool vma_is_valid(struct vm_area_struct
*vma
, bool write_fault
)
1450 if (unlikely(!(vma
->vm_flags
& VM_READ
)))
1453 if (write_fault
&& (unlikely(!(vma
->vm_flags
& VM_WRITE
))))
1459 static int hva_to_pfn_remapped(struct vm_area_struct
*vma
,
1460 unsigned long addr
, bool *async
,
1461 bool write_fault
, kvm_pfn_t
*p_pfn
)
1466 r
= follow_pfn(vma
, addr
, &pfn
);
1469 * get_user_pages fails for VM_IO and VM_PFNMAP vmas and does
1470 * not call the fault handler, so do it here.
1472 bool unlocked
= false;
1473 r
= fixup_user_fault(current
, current
->mm
, addr
,
1474 (write_fault
? FAULT_FLAG_WRITE
: 0),
1481 r
= follow_pfn(vma
, addr
, &pfn
);
1489 * Get a reference here because callers of *hva_to_pfn* and
1490 * *gfn_to_pfn* ultimately call kvm_release_pfn_clean on the
1491 * returned pfn. This is only needed if the VMA has VM_MIXEDMAP
1492 * set, but the kvm_get_pfn/kvm_release_pfn_clean pair will
1493 * simply do nothing for reserved pfns.
1495 * Whoever called remap_pfn_range is also going to call e.g.
1496 * unmap_mapping_range before the underlying pages are freed,
1497 * causing a call to our MMU notifier.
1506 * Pin guest page in memory and return its pfn.
1507 * @addr: host virtual address which maps memory to the guest
1508 * @atomic: whether this function can sleep
1509 * @async: whether this function need to wait IO complete if the
1510 * host page is not in the memory
1511 * @write_fault: whether we should get a writable host page
1512 * @writable: whether it allows to map a writable host page for !@write_fault
1514 * The function will map a writable host page for these two cases:
1515 * 1): @write_fault = true
1516 * 2): @write_fault = false && @writable, @writable will tell the caller
1517 * whether the mapping is writable.
1519 static kvm_pfn_t
hva_to_pfn(unsigned long addr
, bool atomic
, bool *async
,
1520 bool write_fault
, bool *writable
)
1522 struct vm_area_struct
*vma
;
1526 /* we can do it either atomically or asynchronously, not both */
1527 BUG_ON(atomic
&& async
);
1529 if (hva_to_pfn_fast(addr
, atomic
, async
, write_fault
, writable
, &pfn
))
1533 return KVM_PFN_ERR_FAULT
;
1535 npages
= hva_to_pfn_slow(addr
, async
, write_fault
, writable
, &pfn
);
1539 down_read(¤t
->mm
->mmap_sem
);
1540 if (npages
== -EHWPOISON
||
1541 (!async
&& check_user_page_hwpoison(addr
))) {
1542 pfn
= KVM_PFN_ERR_HWPOISON
;
1547 vma
= find_vma_intersection(current
->mm
, addr
, addr
+ 1);
1550 pfn
= KVM_PFN_ERR_FAULT
;
1551 else if (vma
->vm_flags
& (VM_IO
| VM_PFNMAP
)) {
1552 r
= hva_to_pfn_remapped(vma
, addr
, async
, write_fault
, &pfn
);
1556 pfn
= KVM_PFN_ERR_FAULT
;
1558 if (async
&& vma_is_valid(vma
, write_fault
))
1560 pfn
= KVM_PFN_ERR_FAULT
;
1563 up_read(¤t
->mm
->mmap_sem
);
1567 kvm_pfn_t
__gfn_to_pfn_memslot(struct kvm_memory_slot
*slot
, gfn_t gfn
,
1568 bool atomic
, bool *async
, bool write_fault
,
1571 unsigned long addr
= __gfn_to_hva_many(slot
, gfn
, NULL
, write_fault
);
1573 if (addr
== KVM_HVA_ERR_RO_BAD
) {
1576 return KVM_PFN_ERR_RO_FAULT
;
1579 if (kvm_is_error_hva(addr
)) {
1582 return KVM_PFN_NOSLOT
;
1585 /* Do not map writable pfn in the readonly memslot. */
1586 if (writable
&& memslot_is_readonly(slot
)) {
1591 return hva_to_pfn(addr
, atomic
, async
, write_fault
,
1594 EXPORT_SYMBOL_GPL(__gfn_to_pfn_memslot
);
1596 kvm_pfn_t
gfn_to_pfn_prot(struct kvm
*kvm
, gfn_t gfn
, bool write_fault
,
1599 return __gfn_to_pfn_memslot(gfn_to_memslot(kvm
, gfn
), gfn
, false, NULL
,
1600 write_fault
, writable
);
1602 EXPORT_SYMBOL_GPL(gfn_to_pfn_prot
);
1604 kvm_pfn_t
gfn_to_pfn_memslot(struct kvm_memory_slot
*slot
, gfn_t gfn
)
1606 return __gfn_to_pfn_memslot(slot
, gfn
, false, NULL
, true, NULL
);
1608 EXPORT_SYMBOL_GPL(gfn_to_pfn_memslot
);
1610 kvm_pfn_t
gfn_to_pfn_memslot_atomic(struct kvm_memory_slot
*slot
, gfn_t gfn
)
1612 return __gfn_to_pfn_memslot(slot
, gfn
, true, NULL
, true, NULL
);
1614 EXPORT_SYMBOL_GPL(gfn_to_pfn_memslot_atomic
);
1616 kvm_pfn_t
gfn_to_pfn_atomic(struct kvm
*kvm
, gfn_t gfn
)
1618 return gfn_to_pfn_memslot_atomic(gfn_to_memslot(kvm
, gfn
), gfn
);
1620 EXPORT_SYMBOL_GPL(gfn_to_pfn_atomic
);
1622 kvm_pfn_t
kvm_vcpu_gfn_to_pfn_atomic(struct kvm_vcpu
*vcpu
, gfn_t gfn
)
1624 return gfn_to_pfn_memslot_atomic(kvm_vcpu_gfn_to_memslot(vcpu
, gfn
), gfn
);
1626 EXPORT_SYMBOL_GPL(kvm_vcpu_gfn_to_pfn_atomic
);
1628 kvm_pfn_t
gfn_to_pfn(struct kvm
*kvm
, gfn_t gfn
)
1630 return gfn_to_pfn_memslot(gfn_to_memslot(kvm
, gfn
), gfn
);
1632 EXPORT_SYMBOL_GPL(gfn_to_pfn
);
1634 kvm_pfn_t
kvm_vcpu_gfn_to_pfn(struct kvm_vcpu
*vcpu
, gfn_t gfn
)
1636 return gfn_to_pfn_memslot(kvm_vcpu_gfn_to_memslot(vcpu
, gfn
), gfn
);
1638 EXPORT_SYMBOL_GPL(kvm_vcpu_gfn_to_pfn
);
1640 int gfn_to_page_many_atomic(struct kvm_memory_slot
*slot
, gfn_t gfn
,
1641 struct page
**pages
, int nr_pages
)
1646 addr
= gfn_to_hva_many(slot
, gfn
, &entry
);
1647 if (kvm_is_error_hva(addr
))
1650 if (entry
< nr_pages
)
1653 return __get_user_pages_fast(addr
, nr_pages
, 1, pages
);
1655 EXPORT_SYMBOL_GPL(gfn_to_page_many_atomic
);
1657 static struct page
*kvm_pfn_to_page(kvm_pfn_t pfn
)
1659 if (is_error_noslot_pfn(pfn
))
1660 return KVM_ERR_PTR_BAD_PAGE
;
1662 if (kvm_is_reserved_pfn(pfn
)) {
1664 return KVM_ERR_PTR_BAD_PAGE
;
1667 return pfn_to_page(pfn
);
1670 struct page
*gfn_to_page(struct kvm
*kvm
, gfn_t gfn
)
1674 pfn
= gfn_to_pfn(kvm
, gfn
);
1676 return kvm_pfn_to_page(pfn
);
1678 EXPORT_SYMBOL_GPL(gfn_to_page
);
1680 struct page
*kvm_vcpu_gfn_to_page(struct kvm_vcpu
*vcpu
, gfn_t gfn
)
1684 pfn
= kvm_vcpu_gfn_to_pfn(vcpu
, gfn
);
1686 return kvm_pfn_to_page(pfn
);
1688 EXPORT_SYMBOL_GPL(kvm_vcpu_gfn_to_page
);
1690 void kvm_release_page_clean(struct page
*page
)
1692 WARN_ON(is_error_page(page
));
1694 kvm_release_pfn_clean(page_to_pfn(page
));
1696 EXPORT_SYMBOL_GPL(kvm_release_page_clean
);
1698 void kvm_release_pfn_clean(kvm_pfn_t pfn
)
1700 if (!is_error_noslot_pfn(pfn
) && !kvm_is_reserved_pfn(pfn
))
1701 put_page(pfn_to_page(pfn
));
1703 EXPORT_SYMBOL_GPL(kvm_release_pfn_clean
);
1705 void kvm_release_page_dirty(struct page
*page
)
1707 WARN_ON(is_error_page(page
));
1709 kvm_release_pfn_dirty(page_to_pfn(page
));
1711 EXPORT_SYMBOL_GPL(kvm_release_page_dirty
);
1713 static void kvm_release_pfn_dirty(kvm_pfn_t pfn
)
1715 kvm_set_pfn_dirty(pfn
);
1716 kvm_release_pfn_clean(pfn
);
1719 void kvm_set_pfn_dirty(kvm_pfn_t pfn
)
1721 if (!kvm_is_reserved_pfn(pfn
)) {
1722 struct page
*page
= pfn_to_page(pfn
);
1724 if (!PageReserved(page
))
1728 EXPORT_SYMBOL_GPL(kvm_set_pfn_dirty
);
1730 void kvm_set_pfn_accessed(kvm_pfn_t pfn
)
1732 if (!kvm_is_reserved_pfn(pfn
))
1733 mark_page_accessed(pfn_to_page(pfn
));
1735 EXPORT_SYMBOL_GPL(kvm_set_pfn_accessed
);
1737 void kvm_get_pfn(kvm_pfn_t pfn
)
1739 if (!kvm_is_reserved_pfn(pfn
))
1740 get_page(pfn_to_page(pfn
));
1742 EXPORT_SYMBOL_GPL(kvm_get_pfn
);
1744 static int next_segment(unsigned long len
, int offset
)
1746 if (len
> PAGE_SIZE
- offset
)
1747 return PAGE_SIZE
- offset
;
1752 static int __kvm_read_guest_page(struct kvm_memory_slot
*slot
, gfn_t gfn
,
1753 void *data
, int offset
, int len
)
1758 addr
= gfn_to_hva_memslot_prot(slot
, gfn
, NULL
);
1759 if (kvm_is_error_hva(addr
))
1761 r
= __copy_from_user(data
, (void __user
*)addr
+ offset
, len
);
1767 int kvm_read_guest_page(struct kvm
*kvm
, gfn_t gfn
, void *data
, int offset
,
1770 struct kvm_memory_slot
*slot
= gfn_to_memslot(kvm
, gfn
);
1772 return __kvm_read_guest_page(slot
, gfn
, data
, offset
, len
);
1774 EXPORT_SYMBOL_GPL(kvm_read_guest_page
);
1776 int kvm_vcpu_read_guest_page(struct kvm_vcpu
*vcpu
, gfn_t gfn
, void *data
,
1777 int offset
, int len
)
1779 struct kvm_memory_slot
*slot
= kvm_vcpu_gfn_to_memslot(vcpu
, gfn
);
1781 return __kvm_read_guest_page(slot
, gfn
, data
, offset
, len
);
1783 EXPORT_SYMBOL_GPL(kvm_vcpu_read_guest_page
);
1785 int kvm_read_guest(struct kvm
*kvm
, gpa_t gpa
, void *data
, unsigned long len
)
1787 gfn_t gfn
= gpa
>> PAGE_SHIFT
;
1789 int offset
= offset_in_page(gpa
);
1792 while ((seg
= next_segment(len
, offset
)) != 0) {
1793 ret
= kvm_read_guest_page(kvm
, gfn
, data
, offset
, seg
);
1803 EXPORT_SYMBOL_GPL(kvm_read_guest
);
1805 int kvm_vcpu_read_guest(struct kvm_vcpu
*vcpu
, gpa_t gpa
, void *data
, unsigned long len
)
1807 gfn_t gfn
= gpa
>> PAGE_SHIFT
;
1809 int offset
= offset_in_page(gpa
);
1812 while ((seg
= next_segment(len
, offset
)) != 0) {
1813 ret
= kvm_vcpu_read_guest_page(vcpu
, gfn
, data
, offset
, seg
);
1823 EXPORT_SYMBOL_GPL(kvm_vcpu_read_guest
);
1825 static int __kvm_read_guest_atomic(struct kvm_memory_slot
*slot
, gfn_t gfn
,
1826 void *data
, int offset
, unsigned long len
)
1831 addr
= gfn_to_hva_memslot_prot(slot
, gfn
, NULL
);
1832 if (kvm_is_error_hva(addr
))
1834 pagefault_disable();
1835 r
= __copy_from_user_inatomic(data
, (void __user
*)addr
+ offset
, len
);
1842 int kvm_read_guest_atomic(struct kvm
*kvm
, gpa_t gpa
, void *data
,
1845 gfn_t gfn
= gpa
>> PAGE_SHIFT
;
1846 struct kvm_memory_slot
*slot
= gfn_to_memslot(kvm
, gfn
);
1847 int offset
= offset_in_page(gpa
);
1849 return __kvm_read_guest_atomic(slot
, gfn
, data
, offset
, len
);
1851 EXPORT_SYMBOL_GPL(kvm_read_guest_atomic
);
1853 int kvm_vcpu_read_guest_atomic(struct kvm_vcpu
*vcpu
, gpa_t gpa
,
1854 void *data
, unsigned long len
)
1856 gfn_t gfn
= gpa
>> PAGE_SHIFT
;
1857 struct kvm_memory_slot
*slot
= kvm_vcpu_gfn_to_memslot(vcpu
, gfn
);
1858 int offset
= offset_in_page(gpa
);
1860 return __kvm_read_guest_atomic(slot
, gfn
, data
, offset
, len
);
1862 EXPORT_SYMBOL_GPL(kvm_vcpu_read_guest_atomic
);
1864 static int __kvm_write_guest_page(struct kvm_memory_slot
*memslot
, gfn_t gfn
,
1865 const void *data
, int offset
, int len
)
1870 addr
= gfn_to_hva_memslot(memslot
, gfn
);
1871 if (kvm_is_error_hva(addr
))
1873 r
= __copy_to_user((void __user
*)addr
+ offset
, data
, len
);
1876 mark_page_dirty_in_slot(memslot
, gfn
);
1880 int kvm_write_guest_page(struct kvm
*kvm
, gfn_t gfn
,
1881 const void *data
, int offset
, int len
)
1883 struct kvm_memory_slot
*slot
= gfn_to_memslot(kvm
, gfn
);
1885 return __kvm_write_guest_page(slot
, gfn
, data
, offset
, len
);
1887 EXPORT_SYMBOL_GPL(kvm_write_guest_page
);
1889 int kvm_vcpu_write_guest_page(struct kvm_vcpu
*vcpu
, gfn_t gfn
,
1890 const void *data
, int offset
, int len
)
1892 struct kvm_memory_slot
*slot
= kvm_vcpu_gfn_to_memslot(vcpu
, gfn
);
1894 return __kvm_write_guest_page(slot
, gfn
, data
, offset
, len
);
1896 EXPORT_SYMBOL_GPL(kvm_vcpu_write_guest_page
);
1898 int kvm_write_guest(struct kvm
*kvm
, gpa_t gpa
, const void *data
,
1901 gfn_t gfn
= gpa
>> PAGE_SHIFT
;
1903 int offset
= offset_in_page(gpa
);
1906 while ((seg
= next_segment(len
, offset
)) != 0) {
1907 ret
= kvm_write_guest_page(kvm
, gfn
, data
, offset
, seg
);
1917 EXPORT_SYMBOL_GPL(kvm_write_guest
);
1919 int kvm_vcpu_write_guest(struct kvm_vcpu
*vcpu
, gpa_t gpa
, const void *data
,
1922 gfn_t gfn
= gpa
>> PAGE_SHIFT
;
1924 int offset
= offset_in_page(gpa
);
1927 while ((seg
= next_segment(len
, offset
)) != 0) {
1928 ret
= kvm_vcpu_write_guest_page(vcpu
, gfn
, data
, offset
, seg
);
1938 EXPORT_SYMBOL_GPL(kvm_vcpu_write_guest
);
1940 int kvm_gfn_to_hva_cache_init(struct kvm
*kvm
, struct gfn_to_hva_cache
*ghc
,
1941 gpa_t gpa
, unsigned long len
)
1943 struct kvm_memslots
*slots
= kvm_memslots(kvm
);
1944 int offset
= offset_in_page(gpa
);
1945 gfn_t start_gfn
= gpa
>> PAGE_SHIFT
;
1946 gfn_t end_gfn
= (gpa
+ len
- 1) >> PAGE_SHIFT
;
1947 gfn_t nr_pages_needed
= end_gfn
- start_gfn
+ 1;
1948 gfn_t nr_pages_avail
;
1951 ghc
->generation
= slots
->generation
;
1953 ghc
->memslot
= gfn_to_memslot(kvm
, start_gfn
);
1954 ghc
->hva
= gfn_to_hva_many(ghc
->memslot
, start_gfn
, NULL
);
1955 if (!kvm_is_error_hva(ghc
->hva
) && nr_pages_needed
<= 1) {
1959 * If the requested region crosses two memslots, we still
1960 * verify that the entire region is valid here.
1962 while (start_gfn
<= end_gfn
) {
1963 ghc
->memslot
= gfn_to_memslot(kvm
, start_gfn
);
1964 ghc
->hva
= gfn_to_hva_many(ghc
->memslot
, start_gfn
,
1966 if (kvm_is_error_hva(ghc
->hva
))
1968 start_gfn
+= nr_pages_avail
;
1970 /* Use the slow path for cross page reads and writes. */
1971 ghc
->memslot
= NULL
;
1975 EXPORT_SYMBOL_GPL(kvm_gfn_to_hva_cache_init
);
1977 int kvm_write_guest_cached(struct kvm
*kvm
, struct gfn_to_hva_cache
*ghc
,
1978 void *data
, unsigned long len
)
1980 struct kvm_memslots
*slots
= kvm_memslots(kvm
);
1983 BUG_ON(len
> ghc
->len
);
1985 if (slots
->generation
!= ghc
->generation
)
1986 kvm_gfn_to_hva_cache_init(kvm
, ghc
, ghc
->gpa
, ghc
->len
);
1988 if (unlikely(!ghc
->memslot
))
1989 return kvm_write_guest(kvm
, ghc
->gpa
, data
, len
);
1991 if (kvm_is_error_hva(ghc
->hva
))
1994 r
= __copy_to_user((void __user
*)ghc
->hva
, data
, len
);
1997 mark_page_dirty_in_slot(ghc
->memslot
, ghc
->gpa
>> PAGE_SHIFT
);
2001 EXPORT_SYMBOL_GPL(kvm_write_guest_cached
);
2003 int kvm_read_guest_cached(struct kvm
*kvm
, struct gfn_to_hva_cache
*ghc
,
2004 void *data
, unsigned long len
)
2006 struct kvm_memslots
*slots
= kvm_memslots(kvm
);
2009 BUG_ON(len
> ghc
->len
);
2011 if (slots
->generation
!= ghc
->generation
)
2012 kvm_gfn_to_hva_cache_init(kvm
, ghc
, ghc
->gpa
, ghc
->len
);
2014 if (unlikely(!ghc
->memslot
))
2015 return kvm_read_guest(kvm
, ghc
->gpa
, data
, len
);
2017 if (kvm_is_error_hva(ghc
->hva
))
2020 r
= __copy_from_user(data
, (void __user
*)ghc
->hva
, len
);
2026 EXPORT_SYMBOL_GPL(kvm_read_guest_cached
);
2028 int kvm_clear_guest_page(struct kvm
*kvm
, gfn_t gfn
, int offset
, int len
)
2030 const void *zero_page
= (const void *) __va(page_to_phys(ZERO_PAGE(0)));
2032 return kvm_write_guest_page(kvm
, gfn
, zero_page
, offset
, len
);
2034 EXPORT_SYMBOL_GPL(kvm_clear_guest_page
);
2036 int kvm_clear_guest(struct kvm
*kvm
, gpa_t gpa
, unsigned long len
)
2038 gfn_t gfn
= gpa
>> PAGE_SHIFT
;
2040 int offset
= offset_in_page(gpa
);
2043 while ((seg
= next_segment(len
, offset
)) != 0) {
2044 ret
= kvm_clear_guest_page(kvm
, gfn
, offset
, seg
);
2053 EXPORT_SYMBOL_GPL(kvm_clear_guest
);
2055 static void mark_page_dirty_in_slot(struct kvm_memory_slot
*memslot
,
2058 if (memslot
&& memslot
->dirty_bitmap
) {
2059 unsigned long rel_gfn
= gfn
- memslot
->base_gfn
;
2061 set_bit_le(rel_gfn
, memslot
->dirty_bitmap
);
2065 void mark_page_dirty(struct kvm
*kvm
, gfn_t gfn
)
2067 struct kvm_memory_slot
*memslot
;
2069 memslot
= gfn_to_memslot(kvm
, gfn
);
2070 mark_page_dirty_in_slot(memslot
, gfn
);
2072 EXPORT_SYMBOL_GPL(mark_page_dirty
);
2074 void kvm_vcpu_mark_page_dirty(struct kvm_vcpu
*vcpu
, gfn_t gfn
)
2076 struct kvm_memory_slot
*memslot
;
2078 memslot
= kvm_vcpu_gfn_to_memslot(vcpu
, gfn
);
2079 mark_page_dirty_in_slot(memslot
, gfn
);
2081 EXPORT_SYMBOL_GPL(kvm_vcpu_mark_page_dirty
);
2083 static void grow_halt_poll_ns(struct kvm_vcpu
*vcpu
)
2085 unsigned int old
, val
, grow
;
2087 old
= val
= vcpu
->halt_poll_ns
;
2088 grow
= READ_ONCE(halt_poll_ns_grow
);
2090 if (val
== 0 && grow
)
2095 if (val
> halt_poll_ns
)
2098 vcpu
->halt_poll_ns
= val
;
2099 trace_kvm_halt_poll_ns_grow(vcpu
->vcpu_id
, val
, old
);
2102 static void shrink_halt_poll_ns(struct kvm_vcpu
*vcpu
)
2104 unsigned int old
, val
, shrink
;
2106 old
= val
= vcpu
->halt_poll_ns
;
2107 shrink
= READ_ONCE(halt_poll_ns_shrink
);
2113 vcpu
->halt_poll_ns
= val
;
2114 trace_kvm_halt_poll_ns_shrink(vcpu
->vcpu_id
, val
, old
);
2117 static int kvm_vcpu_check_block(struct kvm_vcpu
*vcpu
)
2119 if (kvm_arch_vcpu_runnable(vcpu
)) {
2120 kvm_make_request(KVM_REQ_UNHALT
, vcpu
);
2123 if (kvm_cpu_has_pending_timer(vcpu
))
2125 if (signal_pending(current
))
2132 * The vCPU has executed a HLT instruction with in-kernel mode enabled.
2134 void kvm_vcpu_block(struct kvm_vcpu
*vcpu
)
2137 DECLARE_SWAITQUEUE(wait
);
2138 bool waited
= false;
2141 start
= cur
= ktime_get();
2142 if (vcpu
->halt_poll_ns
) {
2143 ktime_t stop
= ktime_add_ns(ktime_get(), vcpu
->halt_poll_ns
);
2145 ++vcpu
->stat
.halt_attempted_poll
;
2148 * This sets KVM_REQ_UNHALT if an interrupt
2151 if (kvm_vcpu_check_block(vcpu
) < 0) {
2152 ++vcpu
->stat
.halt_successful_poll
;
2153 if (!vcpu_valid_wakeup(vcpu
))
2154 ++vcpu
->stat
.halt_poll_invalid
;
2158 } while (single_task_running() && ktime_before(cur
, stop
));
2161 kvm_arch_vcpu_blocking(vcpu
);
2164 prepare_to_swait(&vcpu
->wq
, &wait
, TASK_INTERRUPTIBLE
);
2166 if (kvm_vcpu_check_block(vcpu
) < 0)
2173 finish_swait(&vcpu
->wq
, &wait
);
2176 kvm_arch_vcpu_unblocking(vcpu
);
2178 block_ns
= ktime_to_ns(cur
) - ktime_to_ns(start
);
2180 if (!vcpu_valid_wakeup(vcpu
))
2181 shrink_halt_poll_ns(vcpu
);
2182 else if (halt_poll_ns
) {
2183 if (block_ns
<= vcpu
->halt_poll_ns
)
2185 /* we had a long block, shrink polling */
2186 else if (vcpu
->halt_poll_ns
&& block_ns
> halt_poll_ns
)
2187 shrink_halt_poll_ns(vcpu
);
2188 /* we had a short halt and our poll time is too small */
2189 else if (vcpu
->halt_poll_ns
< halt_poll_ns
&&
2190 block_ns
< halt_poll_ns
)
2191 grow_halt_poll_ns(vcpu
);
2193 vcpu
->halt_poll_ns
= 0;
2195 trace_kvm_vcpu_wakeup(block_ns
, waited
, vcpu_valid_wakeup(vcpu
));
2196 kvm_arch_vcpu_block_finish(vcpu
);
2198 EXPORT_SYMBOL_GPL(kvm_vcpu_block
);
2201 void kvm_vcpu_wake_up(struct kvm_vcpu
*vcpu
)
2203 struct swait_queue_head
*wqp
;
2205 wqp
= kvm_arch_vcpu_wq(vcpu
);
2206 if (swait_active(wqp
)) {
2208 ++vcpu
->stat
.halt_wakeup
;
2212 EXPORT_SYMBOL_GPL(kvm_vcpu_wake_up
);
2215 * Kick a sleeping VCPU, or a guest VCPU in guest mode, into host kernel mode.
2217 void kvm_vcpu_kick(struct kvm_vcpu
*vcpu
)
2220 int cpu
= vcpu
->cpu
;
2222 kvm_vcpu_wake_up(vcpu
);
2224 if (cpu
!= me
&& (unsigned)cpu
< nr_cpu_ids
&& cpu_online(cpu
))
2225 if (kvm_arch_vcpu_should_kick(vcpu
))
2226 smp_send_reschedule(cpu
);
2229 EXPORT_SYMBOL_GPL(kvm_vcpu_kick
);
2230 #endif /* !CONFIG_S390 */
2232 int kvm_vcpu_yield_to(struct kvm_vcpu
*target
)
2235 struct task_struct
*task
= NULL
;
2239 pid
= rcu_dereference(target
->pid
);
2241 task
= get_pid_task(pid
, PIDTYPE_PID
);
2245 ret
= yield_to(task
, 1);
2246 put_task_struct(task
);
2250 EXPORT_SYMBOL_GPL(kvm_vcpu_yield_to
);
2253 * Helper that checks whether a VCPU is eligible for directed yield.
2254 * Most eligible candidate to yield is decided by following heuristics:
2256 * (a) VCPU which has not done pl-exit or cpu relax intercepted recently
2257 * (preempted lock holder), indicated by @in_spin_loop.
2258 * Set at the beiginning and cleared at the end of interception/PLE handler.
2260 * (b) VCPU which has done pl-exit/ cpu relax intercepted but did not get
2261 * chance last time (mostly it has become eligible now since we have probably
2262 * yielded to lockholder in last iteration. This is done by toggling
2263 * @dy_eligible each time a VCPU checked for eligibility.)
2265 * Yielding to a recently pl-exited/cpu relax intercepted VCPU before yielding
2266 * to preempted lock-holder could result in wrong VCPU selection and CPU
2267 * burning. Giving priority for a potential lock-holder increases lock
2270 * Since algorithm is based on heuristics, accessing another VCPU data without
2271 * locking does not harm. It may result in trying to yield to same VCPU, fail
2272 * and continue with next VCPU and so on.
2274 static bool kvm_vcpu_eligible_for_directed_yield(struct kvm_vcpu
*vcpu
)
2276 #ifdef CONFIG_HAVE_KVM_CPU_RELAX_INTERCEPT
2279 eligible
= !vcpu
->spin_loop
.in_spin_loop
||
2280 vcpu
->spin_loop
.dy_eligible
;
2282 if (vcpu
->spin_loop
.in_spin_loop
)
2283 kvm_vcpu_set_dy_eligible(vcpu
, !vcpu
->spin_loop
.dy_eligible
);
2291 void kvm_vcpu_on_spin(struct kvm_vcpu
*me
)
2293 struct kvm
*kvm
= me
->kvm
;
2294 struct kvm_vcpu
*vcpu
;
2295 int last_boosted_vcpu
= me
->kvm
->last_boosted_vcpu
;
2301 kvm_vcpu_set_in_spin_loop(me
, true);
2303 * We boost the priority of a VCPU that is runnable but not
2304 * currently running, because it got preempted by something
2305 * else and called schedule in __vcpu_run. Hopefully that
2306 * VCPU is holding the lock that we need and will release it.
2307 * We approximate round-robin by starting at the last boosted VCPU.
2309 for (pass
= 0; pass
< 2 && !yielded
&& try; pass
++) {
2310 kvm_for_each_vcpu(i
, vcpu
, kvm
) {
2311 if (!pass
&& i
<= last_boosted_vcpu
) {
2312 i
= last_boosted_vcpu
;
2314 } else if (pass
&& i
> last_boosted_vcpu
)
2316 if (!ACCESS_ONCE(vcpu
->preempted
))
2320 if (swait_active(&vcpu
->wq
) && !kvm_arch_vcpu_runnable(vcpu
))
2322 if (!kvm_vcpu_eligible_for_directed_yield(vcpu
))
2325 yielded
= kvm_vcpu_yield_to(vcpu
);
2327 kvm
->last_boosted_vcpu
= i
;
2329 } else if (yielded
< 0) {
2336 kvm_vcpu_set_in_spin_loop(me
, false);
2338 /* Ensure vcpu is not eligible during next spinloop */
2339 kvm_vcpu_set_dy_eligible(me
, false);
2341 EXPORT_SYMBOL_GPL(kvm_vcpu_on_spin
);
2343 static int kvm_vcpu_fault(struct vm_area_struct
*vma
, struct vm_fault
*vmf
)
2345 struct kvm_vcpu
*vcpu
= vma
->vm_file
->private_data
;
2348 if (vmf
->pgoff
== 0)
2349 page
= virt_to_page(vcpu
->run
);
2351 else if (vmf
->pgoff
== KVM_PIO_PAGE_OFFSET
)
2352 page
= virt_to_page(vcpu
->arch
.pio_data
);
2354 #ifdef KVM_COALESCED_MMIO_PAGE_OFFSET
2355 else if (vmf
->pgoff
== KVM_COALESCED_MMIO_PAGE_OFFSET
)
2356 page
= virt_to_page(vcpu
->kvm
->coalesced_mmio_ring
);
2359 return kvm_arch_vcpu_fault(vcpu
, vmf
);
2365 static const struct vm_operations_struct kvm_vcpu_vm_ops
= {
2366 .fault
= kvm_vcpu_fault
,
2369 static int kvm_vcpu_mmap(struct file
*file
, struct vm_area_struct
*vma
)
2371 vma
->vm_ops
= &kvm_vcpu_vm_ops
;
2375 static int kvm_vcpu_release(struct inode
*inode
, struct file
*filp
)
2377 struct kvm_vcpu
*vcpu
= filp
->private_data
;
2379 debugfs_remove_recursive(vcpu
->debugfs_dentry
);
2380 kvm_put_kvm(vcpu
->kvm
);
2384 static struct file_operations kvm_vcpu_fops
= {
2385 .release
= kvm_vcpu_release
,
2386 .unlocked_ioctl
= kvm_vcpu_ioctl
,
2387 #ifdef CONFIG_KVM_COMPAT
2388 .compat_ioctl
= kvm_vcpu_compat_ioctl
,
2390 .mmap
= kvm_vcpu_mmap
,
2391 .llseek
= noop_llseek
,
2395 * Allocates an inode for the vcpu.
2397 static int create_vcpu_fd(struct kvm_vcpu
*vcpu
)
2399 return anon_inode_getfd("kvm-vcpu", &kvm_vcpu_fops
, vcpu
, O_RDWR
| O_CLOEXEC
);
2402 static int kvm_create_vcpu_debugfs(struct kvm_vcpu
*vcpu
)
2404 char dir_name
[ITOA_MAX_LEN
* 2];
2407 if (!kvm_arch_has_vcpu_debugfs())
2410 if (!debugfs_initialized())
2413 snprintf(dir_name
, sizeof(dir_name
), "vcpu%d", vcpu
->vcpu_id
);
2414 vcpu
->debugfs_dentry
= debugfs_create_dir(dir_name
,
2415 vcpu
->kvm
->debugfs_dentry
);
2416 if (!vcpu
->debugfs_dentry
)
2419 ret
= kvm_arch_create_vcpu_debugfs(vcpu
);
2421 debugfs_remove_recursive(vcpu
->debugfs_dentry
);
2429 * Creates some virtual cpus. Good luck creating more than one.
2431 static int kvm_vm_ioctl_create_vcpu(struct kvm
*kvm
, u32 id
)
2434 struct kvm_vcpu
*vcpu
;
2436 if (id
>= KVM_MAX_VCPU_ID
)
2439 mutex_lock(&kvm
->lock
);
2440 if (kvm
->created_vcpus
== KVM_MAX_VCPUS
) {
2441 mutex_unlock(&kvm
->lock
);
2445 kvm
->created_vcpus
++;
2446 mutex_unlock(&kvm
->lock
);
2448 vcpu
= kvm_arch_vcpu_create(kvm
, id
);
2451 goto vcpu_decrement
;
2454 preempt_notifier_init(&vcpu
->preempt_notifier
, &kvm_preempt_ops
);
2456 r
= kvm_arch_vcpu_setup(vcpu
);
2460 r
= kvm_create_vcpu_debugfs(vcpu
);
2464 mutex_lock(&kvm
->lock
);
2465 if (kvm_get_vcpu_by_id(kvm
, id
)) {
2467 goto unlock_vcpu_destroy
;
2470 BUG_ON(kvm
->vcpus
[atomic_read(&kvm
->online_vcpus
)]);
2472 /* Now it's all set up, let userspace reach it */
2474 r
= create_vcpu_fd(vcpu
);
2477 goto unlock_vcpu_destroy
;
2480 kvm
->vcpus
[atomic_read(&kvm
->online_vcpus
)] = vcpu
;
2483 * Pairs with smp_rmb() in kvm_get_vcpu. Write kvm->vcpus
2484 * before kvm->online_vcpu's incremented value.
2487 atomic_inc(&kvm
->online_vcpus
);
2489 mutex_unlock(&kvm
->lock
);
2490 kvm_arch_vcpu_postcreate(vcpu
);
2493 unlock_vcpu_destroy
:
2494 mutex_unlock(&kvm
->lock
);
2495 debugfs_remove_recursive(vcpu
->debugfs_dentry
);
2497 kvm_arch_vcpu_destroy(vcpu
);
2499 mutex_lock(&kvm
->lock
);
2500 kvm
->created_vcpus
--;
2501 mutex_unlock(&kvm
->lock
);
2505 static int kvm_vcpu_ioctl_set_sigmask(struct kvm_vcpu
*vcpu
, sigset_t
*sigset
)
2508 sigdelsetmask(sigset
, sigmask(SIGKILL
)|sigmask(SIGSTOP
));
2509 vcpu
->sigset_active
= 1;
2510 vcpu
->sigset
= *sigset
;
2512 vcpu
->sigset_active
= 0;
2516 static long kvm_vcpu_ioctl(struct file
*filp
,
2517 unsigned int ioctl
, unsigned long arg
)
2519 struct kvm_vcpu
*vcpu
= filp
->private_data
;
2520 void __user
*argp
= (void __user
*)arg
;
2522 struct kvm_fpu
*fpu
= NULL
;
2523 struct kvm_sregs
*kvm_sregs
= NULL
;
2525 if (vcpu
->kvm
->mm
!= current
->mm
)
2528 if (unlikely(_IOC_TYPE(ioctl
) != KVMIO
))
2531 #if defined(CONFIG_S390) || defined(CONFIG_PPC) || defined(CONFIG_MIPS)
2533 * Special cases: vcpu ioctls that are asynchronous to vcpu execution,
2534 * so vcpu_load() would break it.
2536 if (ioctl
== KVM_S390_INTERRUPT
|| ioctl
== KVM_S390_IRQ
|| ioctl
== KVM_INTERRUPT
)
2537 return kvm_arch_vcpu_ioctl(filp
, ioctl
, arg
);
2541 r
= vcpu_load(vcpu
);
2549 if (unlikely(vcpu
->pid
!= current
->pids
[PIDTYPE_PID
].pid
)) {
2550 /* The thread running this VCPU changed. */
2551 struct pid
*oldpid
= vcpu
->pid
;
2552 struct pid
*newpid
= get_task_pid(current
, PIDTYPE_PID
);
2554 rcu_assign_pointer(vcpu
->pid
, newpid
);
2559 r
= kvm_arch_vcpu_ioctl_run(vcpu
, vcpu
->run
);
2560 trace_kvm_userspace_exit(vcpu
->run
->exit_reason
, r
);
2562 case KVM_GET_REGS
: {
2563 struct kvm_regs
*kvm_regs
;
2566 kvm_regs
= kzalloc(sizeof(struct kvm_regs
), GFP_KERNEL
);
2569 r
= kvm_arch_vcpu_ioctl_get_regs(vcpu
, kvm_regs
);
2573 if (copy_to_user(argp
, kvm_regs
, sizeof(struct kvm_regs
)))
2580 case KVM_SET_REGS
: {
2581 struct kvm_regs
*kvm_regs
;
2584 kvm_regs
= memdup_user(argp
, sizeof(*kvm_regs
));
2585 if (IS_ERR(kvm_regs
)) {
2586 r
= PTR_ERR(kvm_regs
);
2589 r
= kvm_arch_vcpu_ioctl_set_regs(vcpu
, kvm_regs
);
2593 case KVM_GET_SREGS
: {
2594 kvm_sregs
= kzalloc(sizeof(struct kvm_sregs
), GFP_KERNEL
);
2598 r
= kvm_arch_vcpu_ioctl_get_sregs(vcpu
, kvm_sregs
);
2602 if (copy_to_user(argp
, kvm_sregs
, sizeof(struct kvm_sregs
)))
2607 case KVM_SET_SREGS
: {
2608 kvm_sregs
= memdup_user(argp
, sizeof(*kvm_sregs
));
2609 if (IS_ERR(kvm_sregs
)) {
2610 r
= PTR_ERR(kvm_sregs
);
2614 r
= kvm_arch_vcpu_ioctl_set_sregs(vcpu
, kvm_sregs
);
2617 case KVM_GET_MP_STATE
: {
2618 struct kvm_mp_state mp_state
;
2620 r
= kvm_arch_vcpu_ioctl_get_mpstate(vcpu
, &mp_state
);
2624 if (copy_to_user(argp
, &mp_state
, sizeof(mp_state
)))
2629 case KVM_SET_MP_STATE
: {
2630 struct kvm_mp_state mp_state
;
2633 if (copy_from_user(&mp_state
, argp
, sizeof(mp_state
)))
2635 r
= kvm_arch_vcpu_ioctl_set_mpstate(vcpu
, &mp_state
);
2638 case KVM_TRANSLATE
: {
2639 struct kvm_translation tr
;
2642 if (copy_from_user(&tr
, argp
, sizeof(tr
)))
2644 r
= kvm_arch_vcpu_ioctl_translate(vcpu
, &tr
);
2648 if (copy_to_user(argp
, &tr
, sizeof(tr
)))
2653 case KVM_SET_GUEST_DEBUG
: {
2654 struct kvm_guest_debug dbg
;
2657 if (copy_from_user(&dbg
, argp
, sizeof(dbg
)))
2659 r
= kvm_arch_vcpu_ioctl_set_guest_debug(vcpu
, &dbg
);
2662 case KVM_SET_SIGNAL_MASK
: {
2663 struct kvm_signal_mask __user
*sigmask_arg
= argp
;
2664 struct kvm_signal_mask kvm_sigmask
;
2665 sigset_t sigset
, *p
;
2670 if (copy_from_user(&kvm_sigmask
, argp
,
2671 sizeof(kvm_sigmask
)))
2674 if (kvm_sigmask
.len
!= sizeof(sigset
))
2677 if (copy_from_user(&sigset
, sigmask_arg
->sigset
,
2682 r
= kvm_vcpu_ioctl_set_sigmask(vcpu
, p
);
2686 fpu
= kzalloc(sizeof(struct kvm_fpu
), GFP_KERNEL
);
2690 r
= kvm_arch_vcpu_ioctl_get_fpu(vcpu
, fpu
);
2694 if (copy_to_user(argp
, fpu
, sizeof(struct kvm_fpu
)))
2700 fpu
= memdup_user(argp
, sizeof(*fpu
));
2706 r
= kvm_arch_vcpu_ioctl_set_fpu(vcpu
, fpu
);
2710 r
= kvm_arch_vcpu_ioctl(filp
, ioctl
, arg
);
2719 #ifdef CONFIG_KVM_COMPAT
2720 static long kvm_vcpu_compat_ioctl(struct file
*filp
,
2721 unsigned int ioctl
, unsigned long arg
)
2723 struct kvm_vcpu
*vcpu
= filp
->private_data
;
2724 void __user
*argp
= compat_ptr(arg
);
2727 if (vcpu
->kvm
->mm
!= current
->mm
)
2731 case KVM_SET_SIGNAL_MASK
: {
2732 struct kvm_signal_mask __user
*sigmask_arg
= argp
;
2733 struct kvm_signal_mask kvm_sigmask
;
2734 compat_sigset_t csigset
;
2739 if (copy_from_user(&kvm_sigmask
, argp
,
2740 sizeof(kvm_sigmask
)))
2743 if (kvm_sigmask
.len
!= sizeof(csigset
))
2746 if (copy_from_user(&csigset
, sigmask_arg
->sigset
,
2749 sigset_from_compat(&sigset
, &csigset
);
2750 r
= kvm_vcpu_ioctl_set_sigmask(vcpu
, &sigset
);
2752 r
= kvm_vcpu_ioctl_set_sigmask(vcpu
, NULL
);
2756 r
= kvm_vcpu_ioctl(filp
, ioctl
, arg
);
2764 static int kvm_device_ioctl_attr(struct kvm_device
*dev
,
2765 int (*accessor
)(struct kvm_device
*dev
,
2766 struct kvm_device_attr
*attr
),
2769 struct kvm_device_attr attr
;
2774 if (copy_from_user(&attr
, (void __user
*)arg
, sizeof(attr
)))
2777 return accessor(dev
, &attr
);
2780 static long kvm_device_ioctl(struct file
*filp
, unsigned int ioctl
,
2783 struct kvm_device
*dev
= filp
->private_data
;
2786 case KVM_SET_DEVICE_ATTR
:
2787 return kvm_device_ioctl_attr(dev
, dev
->ops
->set_attr
, arg
);
2788 case KVM_GET_DEVICE_ATTR
:
2789 return kvm_device_ioctl_attr(dev
, dev
->ops
->get_attr
, arg
);
2790 case KVM_HAS_DEVICE_ATTR
:
2791 return kvm_device_ioctl_attr(dev
, dev
->ops
->has_attr
, arg
);
2793 if (dev
->ops
->ioctl
)
2794 return dev
->ops
->ioctl(dev
, ioctl
, arg
);
2800 static int kvm_device_release(struct inode
*inode
, struct file
*filp
)
2802 struct kvm_device
*dev
= filp
->private_data
;
2803 struct kvm
*kvm
= dev
->kvm
;
2809 static const struct file_operations kvm_device_fops
= {
2810 .unlocked_ioctl
= kvm_device_ioctl
,
2811 #ifdef CONFIG_KVM_COMPAT
2812 .compat_ioctl
= kvm_device_ioctl
,
2814 .release
= kvm_device_release
,
2817 struct kvm_device
*kvm_device_from_filp(struct file
*filp
)
2819 if (filp
->f_op
!= &kvm_device_fops
)
2822 return filp
->private_data
;
2825 static struct kvm_device_ops
*kvm_device_ops_table
[KVM_DEV_TYPE_MAX
] = {
2826 #ifdef CONFIG_KVM_MPIC
2827 [KVM_DEV_TYPE_FSL_MPIC_20
] = &kvm_mpic_ops
,
2828 [KVM_DEV_TYPE_FSL_MPIC_42
] = &kvm_mpic_ops
,
2831 #ifdef CONFIG_KVM_XICS
2832 [KVM_DEV_TYPE_XICS
] = &kvm_xics_ops
,
2836 int kvm_register_device_ops(struct kvm_device_ops
*ops
, u32 type
)
2838 if (type
>= ARRAY_SIZE(kvm_device_ops_table
))
2841 if (kvm_device_ops_table
[type
] != NULL
)
2844 kvm_device_ops_table
[type
] = ops
;
2848 void kvm_unregister_device_ops(u32 type
)
2850 if (kvm_device_ops_table
[type
] != NULL
)
2851 kvm_device_ops_table
[type
] = NULL
;
2854 static int kvm_ioctl_create_device(struct kvm
*kvm
,
2855 struct kvm_create_device
*cd
)
2857 struct kvm_device_ops
*ops
= NULL
;
2858 struct kvm_device
*dev
;
2859 bool test
= cd
->flags
& KVM_CREATE_DEVICE_TEST
;
2862 if (cd
->type
>= ARRAY_SIZE(kvm_device_ops_table
))
2865 ops
= kvm_device_ops_table
[cd
->type
];
2872 dev
= kzalloc(sizeof(*dev
), GFP_KERNEL
);
2879 mutex_lock(&kvm
->lock
);
2880 ret
= ops
->create(dev
, cd
->type
);
2882 mutex_unlock(&kvm
->lock
);
2886 list_add(&dev
->vm_node
, &kvm
->devices
);
2887 mutex_unlock(&kvm
->lock
);
2892 ret
= anon_inode_getfd(ops
->name
, &kvm_device_fops
, dev
, O_RDWR
| O_CLOEXEC
);
2895 mutex_lock(&kvm
->lock
);
2896 list_del(&dev
->vm_node
);
2897 mutex_unlock(&kvm
->lock
);
2906 static long kvm_vm_ioctl_check_extension_generic(struct kvm
*kvm
, long arg
)
2909 case KVM_CAP_USER_MEMORY
:
2910 case KVM_CAP_DESTROY_MEMORY_REGION_WORKS
:
2911 case KVM_CAP_JOIN_MEMORY_REGIONS_WORKS
:
2912 case KVM_CAP_INTERNAL_ERROR_DATA
:
2913 #ifdef CONFIG_HAVE_KVM_MSI
2914 case KVM_CAP_SIGNAL_MSI
:
2916 #ifdef CONFIG_HAVE_KVM_IRQFD
2918 case KVM_CAP_IRQFD_RESAMPLE
:
2920 case KVM_CAP_IOEVENTFD_ANY_LENGTH
:
2921 case KVM_CAP_CHECK_EXTENSION_VM
:
2923 #ifdef CONFIG_HAVE_KVM_IRQ_ROUTING
2924 case KVM_CAP_IRQ_ROUTING
:
2925 return KVM_MAX_IRQ_ROUTES
;
2927 #if KVM_ADDRESS_SPACE_NUM > 1
2928 case KVM_CAP_MULTI_ADDRESS_SPACE
:
2929 return KVM_ADDRESS_SPACE_NUM
;
2931 case KVM_CAP_MAX_VCPU_ID
:
2932 return KVM_MAX_VCPU_ID
;
2936 return kvm_vm_ioctl_check_extension(kvm
, arg
);
2939 static long kvm_vm_ioctl(struct file
*filp
,
2940 unsigned int ioctl
, unsigned long arg
)
2942 struct kvm
*kvm
= filp
->private_data
;
2943 void __user
*argp
= (void __user
*)arg
;
2946 if (kvm
->mm
!= current
->mm
)
2949 case KVM_CREATE_VCPU
:
2950 r
= kvm_vm_ioctl_create_vcpu(kvm
, arg
);
2952 case KVM_SET_USER_MEMORY_REGION
: {
2953 struct kvm_userspace_memory_region kvm_userspace_mem
;
2956 if (copy_from_user(&kvm_userspace_mem
, argp
,
2957 sizeof(kvm_userspace_mem
)))
2960 r
= kvm_vm_ioctl_set_memory_region(kvm
, &kvm_userspace_mem
);
2963 case KVM_GET_DIRTY_LOG
: {
2964 struct kvm_dirty_log log
;
2967 if (copy_from_user(&log
, argp
, sizeof(log
)))
2969 r
= kvm_vm_ioctl_get_dirty_log(kvm
, &log
);
2972 #ifdef KVM_COALESCED_MMIO_PAGE_OFFSET
2973 case KVM_REGISTER_COALESCED_MMIO
: {
2974 struct kvm_coalesced_mmio_zone zone
;
2977 if (copy_from_user(&zone
, argp
, sizeof(zone
)))
2979 r
= kvm_vm_ioctl_register_coalesced_mmio(kvm
, &zone
);
2982 case KVM_UNREGISTER_COALESCED_MMIO
: {
2983 struct kvm_coalesced_mmio_zone zone
;
2986 if (copy_from_user(&zone
, argp
, sizeof(zone
)))
2988 r
= kvm_vm_ioctl_unregister_coalesced_mmio(kvm
, &zone
);
2993 struct kvm_irqfd data
;
2996 if (copy_from_user(&data
, argp
, sizeof(data
)))
2998 r
= kvm_irqfd(kvm
, &data
);
3001 case KVM_IOEVENTFD
: {
3002 struct kvm_ioeventfd data
;
3005 if (copy_from_user(&data
, argp
, sizeof(data
)))
3007 r
= kvm_ioeventfd(kvm
, &data
);
3010 #ifdef CONFIG_HAVE_KVM_MSI
3011 case KVM_SIGNAL_MSI
: {
3015 if (copy_from_user(&msi
, argp
, sizeof(msi
)))
3017 r
= kvm_send_userspace_msi(kvm
, &msi
);
3021 #ifdef __KVM_HAVE_IRQ_LINE
3022 case KVM_IRQ_LINE_STATUS
:
3023 case KVM_IRQ_LINE
: {
3024 struct kvm_irq_level irq_event
;
3027 if (copy_from_user(&irq_event
, argp
, sizeof(irq_event
)))
3030 r
= kvm_vm_ioctl_irq_line(kvm
, &irq_event
,
3031 ioctl
== KVM_IRQ_LINE_STATUS
);
3036 if (ioctl
== KVM_IRQ_LINE_STATUS
) {
3037 if (copy_to_user(argp
, &irq_event
, sizeof(irq_event
)))
3045 #ifdef CONFIG_HAVE_KVM_IRQ_ROUTING
3046 case KVM_SET_GSI_ROUTING
: {
3047 struct kvm_irq_routing routing
;
3048 struct kvm_irq_routing __user
*urouting
;
3049 struct kvm_irq_routing_entry
*entries
= NULL
;
3052 if (copy_from_user(&routing
, argp
, sizeof(routing
)))
3055 if (routing
.nr
> KVM_MAX_IRQ_ROUTES
)
3061 entries
= vmalloc(routing
.nr
* sizeof(*entries
));
3066 if (copy_from_user(entries
, urouting
->entries
,
3067 routing
.nr
* sizeof(*entries
)))
3068 goto out_free_irq_routing
;
3070 r
= kvm_set_irq_routing(kvm
, entries
, routing
.nr
,
3072 out_free_irq_routing
:
3076 #endif /* CONFIG_HAVE_KVM_IRQ_ROUTING */
3077 case KVM_CREATE_DEVICE
: {
3078 struct kvm_create_device cd
;
3081 if (copy_from_user(&cd
, argp
, sizeof(cd
)))
3084 r
= kvm_ioctl_create_device(kvm
, &cd
);
3089 if (copy_to_user(argp
, &cd
, sizeof(cd
)))
3095 case KVM_CHECK_EXTENSION
:
3096 r
= kvm_vm_ioctl_check_extension_generic(kvm
, arg
);
3099 r
= kvm_arch_vm_ioctl(filp
, ioctl
, arg
);
3105 #ifdef CONFIG_KVM_COMPAT
3106 struct compat_kvm_dirty_log
{
3110 compat_uptr_t dirty_bitmap
; /* one bit per page */
3115 static long kvm_vm_compat_ioctl(struct file
*filp
,
3116 unsigned int ioctl
, unsigned long arg
)
3118 struct kvm
*kvm
= filp
->private_data
;
3121 if (kvm
->mm
!= current
->mm
)
3124 case KVM_GET_DIRTY_LOG
: {
3125 struct compat_kvm_dirty_log compat_log
;
3126 struct kvm_dirty_log log
;
3129 if (copy_from_user(&compat_log
, (void __user
*)arg
,
3130 sizeof(compat_log
)))
3132 log
.slot
= compat_log
.slot
;
3133 log
.padding1
= compat_log
.padding1
;
3134 log
.padding2
= compat_log
.padding2
;
3135 log
.dirty_bitmap
= compat_ptr(compat_log
.dirty_bitmap
);
3137 r
= kvm_vm_ioctl_get_dirty_log(kvm
, &log
);
3141 r
= kvm_vm_ioctl(filp
, ioctl
, arg
);
3149 static struct file_operations kvm_vm_fops
= {
3150 .release
= kvm_vm_release
,
3151 .unlocked_ioctl
= kvm_vm_ioctl
,
3152 #ifdef CONFIG_KVM_COMPAT
3153 .compat_ioctl
= kvm_vm_compat_ioctl
,
3155 .llseek
= noop_llseek
,
3158 static int kvm_dev_ioctl_create_vm(unsigned long type
)
3164 kvm
= kvm_create_vm(type
);
3166 return PTR_ERR(kvm
);
3167 #ifdef KVM_COALESCED_MMIO_PAGE_OFFSET
3168 r
= kvm_coalesced_mmio_init(kvm
);
3174 r
= get_unused_fd_flags(O_CLOEXEC
);
3179 file
= anon_inode_getfile("kvm-vm", &kvm_vm_fops
, kvm
, O_RDWR
);
3183 return PTR_ERR(file
);
3186 if (kvm_create_vm_debugfs(kvm
, r
) < 0) {
3192 fd_install(r
, file
);
3196 static long kvm_dev_ioctl(struct file
*filp
,
3197 unsigned int ioctl
, unsigned long arg
)
3202 case KVM_GET_API_VERSION
:
3205 r
= KVM_API_VERSION
;
3208 r
= kvm_dev_ioctl_create_vm(arg
);
3210 case KVM_CHECK_EXTENSION
:
3211 r
= kvm_vm_ioctl_check_extension_generic(NULL
, arg
);
3213 case KVM_GET_VCPU_MMAP_SIZE
:
3216 r
= PAGE_SIZE
; /* struct kvm_run */
3218 r
+= PAGE_SIZE
; /* pio data page */
3220 #ifdef KVM_COALESCED_MMIO_PAGE_OFFSET
3221 r
+= PAGE_SIZE
; /* coalesced mmio ring page */
3224 case KVM_TRACE_ENABLE
:
3225 case KVM_TRACE_PAUSE
:
3226 case KVM_TRACE_DISABLE
:
3230 return kvm_arch_dev_ioctl(filp
, ioctl
, arg
);
3236 static struct file_operations kvm_chardev_ops
= {
3237 .unlocked_ioctl
= kvm_dev_ioctl
,
3238 .compat_ioctl
= kvm_dev_ioctl
,
3239 .llseek
= noop_llseek
,
3242 static struct miscdevice kvm_dev
= {
3248 static void hardware_enable_nolock(void *junk
)
3250 int cpu
= raw_smp_processor_id();
3253 if (cpumask_test_cpu(cpu
, cpus_hardware_enabled
))
3256 cpumask_set_cpu(cpu
, cpus_hardware_enabled
);
3258 r
= kvm_arch_hardware_enable();
3261 cpumask_clear_cpu(cpu
, cpus_hardware_enabled
);
3262 atomic_inc(&hardware_enable_failed
);
3263 pr_info("kvm: enabling virtualization on CPU%d failed\n", cpu
);
3267 static int kvm_starting_cpu(unsigned int cpu
)
3269 raw_spin_lock(&kvm_count_lock
);
3270 if (kvm_usage_count
)
3271 hardware_enable_nolock(NULL
);
3272 raw_spin_unlock(&kvm_count_lock
);
3276 static void hardware_disable_nolock(void *junk
)
3278 int cpu
= raw_smp_processor_id();
3280 if (!cpumask_test_cpu(cpu
, cpus_hardware_enabled
))
3282 cpumask_clear_cpu(cpu
, cpus_hardware_enabled
);
3283 kvm_arch_hardware_disable();
3286 static int kvm_dying_cpu(unsigned int cpu
)
3288 raw_spin_lock(&kvm_count_lock
);
3289 if (kvm_usage_count
)
3290 hardware_disable_nolock(NULL
);
3291 raw_spin_unlock(&kvm_count_lock
);
3295 static void hardware_disable_all_nolock(void)
3297 BUG_ON(!kvm_usage_count
);
3300 if (!kvm_usage_count
)
3301 on_each_cpu(hardware_disable_nolock
, NULL
, 1);
3304 static void hardware_disable_all(void)
3306 raw_spin_lock(&kvm_count_lock
);
3307 hardware_disable_all_nolock();
3308 raw_spin_unlock(&kvm_count_lock
);
3311 static int hardware_enable_all(void)
3315 raw_spin_lock(&kvm_count_lock
);
3318 if (kvm_usage_count
== 1) {
3319 atomic_set(&hardware_enable_failed
, 0);
3320 on_each_cpu(hardware_enable_nolock
, NULL
, 1);
3322 if (atomic_read(&hardware_enable_failed
)) {
3323 hardware_disable_all_nolock();
3328 raw_spin_unlock(&kvm_count_lock
);
3333 static int kvm_reboot(struct notifier_block
*notifier
, unsigned long val
,
3337 * Some (well, at least mine) BIOSes hang on reboot if
3340 * And Intel TXT required VMX off for all cpu when system shutdown.
3342 pr_info("kvm: exiting hardware virtualization\n");
3343 kvm_rebooting
= true;
3344 on_each_cpu(hardware_disable_nolock
, NULL
, 1);
3348 static struct notifier_block kvm_reboot_notifier
= {
3349 .notifier_call
= kvm_reboot
,
3353 static void kvm_io_bus_destroy(struct kvm_io_bus
*bus
)
3357 for (i
= 0; i
< bus
->dev_count
; i
++) {
3358 struct kvm_io_device
*pos
= bus
->range
[i
].dev
;
3360 kvm_iodevice_destructor(pos
);
3365 static inline int kvm_io_bus_cmp(const struct kvm_io_range
*r1
,
3366 const struct kvm_io_range
*r2
)
3368 gpa_t addr1
= r1
->addr
;
3369 gpa_t addr2
= r2
->addr
;
3374 /* If r2->len == 0, match the exact address. If r2->len != 0,
3375 * accept any overlapping write. Any order is acceptable for
3376 * overlapping ranges, because kvm_io_bus_get_first_dev ensures
3377 * we process all of them.
3390 static int kvm_io_bus_sort_cmp(const void *p1
, const void *p2
)
3392 return kvm_io_bus_cmp(p1
, p2
);
3395 static int kvm_io_bus_insert_dev(struct kvm_io_bus
*bus
, struct kvm_io_device
*dev
,
3396 gpa_t addr
, int len
)
3398 bus
->range
[bus
->dev_count
++] = (struct kvm_io_range
) {
3404 sort(bus
->range
, bus
->dev_count
, sizeof(struct kvm_io_range
),
3405 kvm_io_bus_sort_cmp
, NULL
);
3410 static int kvm_io_bus_get_first_dev(struct kvm_io_bus
*bus
,
3411 gpa_t addr
, int len
)
3413 struct kvm_io_range
*range
, key
;
3416 key
= (struct kvm_io_range
) {
3421 range
= bsearch(&key
, bus
->range
, bus
->dev_count
,
3422 sizeof(struct kvm_io_range
), kvm_io_bus_sort_cmp
);
3426 off
= range
- bus
->range
;
3428 while (off
> 0 && kvm_io_bus_cmp(&key
, &bus
->range
[off
-1]) == 0)
3434 static int __kvm_io_bus_write(struct kvm_vcpu
*vcpu
, struct kvm_io_bus
*bus
,
3435 struct kvm_io_range
*range
, const void *val
)
3439 idx
= kvm_io_bus_get_first_dev(bus
, range
->addr
, range
->len
);
3443 while (idx
< bus
->dev_count
&&
3444 kvm_io_bus_cmp(range
, &bus
->range
[idx
]) == 0) {
3445 if (!kvm_iodevice_write(vcpu
, bus
->range
[idx
].dev
, range
->addr
,
3454 /* kvm_io_bus_write - called under kvm->slots_lock */
3455 int kvm_io_bus_write(struct kvm_vcpu
*vcpu
, enum kvm_bus bus_idx
, gpa_t addr
,
3456 int len
, const void *val
)
3458 struct kvm_io_bus
*bus
;
3459 struct kvm_io_range range
;
3462 range
= (struct kvm_io_range
) {
3467 bus
= srcu_dereference(vcpu
->kvm
->buses
[bus_idx
], &vcpu
->kvm
->srcu
);
3468 r
= __kvm_io_bus_write(vcpu
, bus
, &range
, val
);
3469 return r
< 0 ? r
: 0;
3472 /* kvm_io_bus_write_cookie - called under kvm->slots_lock */
3473 int kvm_io_bus_write_cookie(struct kvm_vcpu
*vcpu
, enum kvm_bus bus_idx
,
3474 gpa_t addr
, int len
, const void *val
, long cookie
)
3476 struct kvm_io_bus
*bus
;
3477 struct kvm_io_range range
;
3479 range
= (struct kvm_io_range
) {
3484 bus
= srcu_dereference(vcpu
->kvm
->buses
[bus_idx
], &vcpu
->kvm
->srcu
);
3486 /* First try the device referenced by cookie. */
3487 if ((cookie
>= 0) && (cookie
< bus
->dev_count
) &&
3488 (kvm_io_bus_cmp(&range
, &bus
->range
[cookie
]) == 0))
3489 if (!kvm_iodevice_write(vcpu
, bus
->range
[cookie
].dev
, addr
, len
,
3494 * cookie contained garbage; fall back to search and return the
3495 * correct cookie value.
3497 return __kvm_io_bus_write(vcpu
, bus
, &range
, val
);
3500 static int __kvm_io_bus_read(struct kvm_vcpu
*vcpu
, struct kvm_io_bus
*bus
,
3501 struct kvm_io_range
*range
, void *val
)
3505 idx
= kvm_io_bus_get_first_dev(bus
, range
->addr
, range
->len
);
3509 while (idx
< bus
->dev_count
&&
3510 kvm_io_bus_cmp(range
, &bus
->range
[idx
]) == 0) {
3511 if (!kvm_iodevice_read(vcpu
, bus
->range
[idx
].dev
, range
->addr
,
3519 EXPORT_SYMBOL_GPL(kvm_io_bus_write
);
3521 /* kvm_io_bus_read - called under kvm->slots_lock */
3522 int kvm_io_bus_read(struct kvm_vcpu
*vcpu
, enum kvm_bus bus_idx
, gpa_t addr
,
3525 struct kvm_io_bus
*bus
;
3526 struct kvm_io_range range
;
3529 range
= (struct kvm_io_range
) {
3534 bus
= srcu_dereference(vcpu
->kvm
->buses
[bus_idx
], &vcpu
->kvm
->srcu
);
3535 r
= __kvm_io_bus_read(vcpu
, bus
, &range
, val
);
3536 return r
< 0 ? r
: 0;
3540 /* Caller must hold slots_lock. */
3541 int kvm_io_bus_register_dev(struct kvm
*kvm
, enum kvm_bus bus_idx
, gpa_t addr
,
3542 int len
, struct kvm_io_device
*dev
)
3544 struct kvm_io_bus
*new_bus
, *bus
;
3546 bus
= kvm
->buses
[bus_idx
];
3547 /* exclude ioeventfd which is limited by maximum fd */
3548 if (bus
->dev_count
- bus
->ioeventfd_count
> NR_IOBUS_DEVS
- 1)
3551 new_bus
= kmalloc(sizeof(*bus
) + ((bus
->dev_count
+ 1) *
3552 sizeof(struct kvm_io_range
)), GFP_KERNEL
);
3555 memcpy(new_bus
, bus
, sizeof(*bus
) + (bus
->dev_count
*
3556 sizeof(struct kvm_io_range
)));
3557 kvm_io_bus_insert_dev(new_bus
, dev
, addr
, len
);
3558 rcu_assign_pointer(kvm
->buses
[bus_idx
], new_bus
);
3559 synchronize_srcu_expedited(&kvm
->srcu
);
3565 /* Caller must hold slots_lock. */
3566 int kvm_io_bus_unregister_dev(struct kvm
*kvm
, enum kvm_bus bus_idx
,
3567 struct kvm_io_device
*dev
)
3570 struct kvm_io_bus
*new_bus
, *bus
;
3572 bus
= kvm
->buses
[bus_idx
];
3574 for (i
= 0; i
< bus
->dev_count
; i
++)
3575 if (bus
->range
[i
].dev
== dev
) {
3583 new_bus
= kmalloc(sizeof(*bus
) + ((bus
->dev_count
- 1) *
3584 sizeof(struct kvm_io_range
)), GFP_KERNEL
);
3588 memcpy(new_bus
, bus
, sizeof(*bus
) + i
* sizeof(struct kvm_io_range
));
3589 new_bus
->dev_count
--;
3590 memcpy(new_bus
->range
+ i
, bus
->range
+ i
+ 1,
3591 (new_bus
->dev_count
- i
) * sizeof(struct kvm_io_range
));
3593 rcu_assign_pointer(kvm
->buses
[bus_idx
], new_bus
);
3594 synchronize_srcu_expedited(&kvm
->srcu
);
3599 struct kvm_io_device
*kvm_io_bus_get_dev(struct kvm
*kvm
, enum kvm_bus bus_idx
,
3602 struct kvm_io_bus
*bus
;
3603 int dev_idx
, srcu_idx
;
3604 struct kvm_io_device
*iodev
= NULL
;
3606 srcu_idx
= srcu_read_lock(&kvm
->srcu
);
3608 bus
= srcu_dereference(kvm
->buses
[bus_idx
], &kvm
->srcu
);
3610 dev_idx
= kvm_io_bus_get_first_dev(bus
, addr
, 1);
3614 iodev
= bus
->range
[dev_idx
].dev
;
3617 srcu_read_unlock(&kvm
->srcu
, srcu_idx
);
3621 EXPORT_SYMBOL_GPL(kvm_io_bus_get_dev
);
3623 static int kvm_debugfs_open(struct inode
*inode
, struct file
*file
,
3624 int (*get
)(void *, u64
*), int (*set
)(void *, u64
),
3627 struct kvm_stat_data
*stat_data
= (struct kvm_stat_data
*)
3630 /* The debugfs files are a reference to the kvm struct which
3631 * is still valid when kvm_destroy_vm is called.
3632 * To avoid the race between open and the removal of the debugfs
3633 * directory we test against the users count.
3635 if (!atomic_add_unless(&stat_data
->kvm
->users_count
, 1, 0))
3638 if (simple_attr_open(inode
, file
, get
, set
, fmt
)) {
3639 kvm_put_kvm(stat_data
->kvm
);
3646 static int kvm_debugfs_release(struct inode
*inode
, struct file
*file
)
3648 struct kvm_stat_data
*stat_data
= (struct kvm_stat_data
*)
3651 simple_attr_release(inode
, file
);
3652 kvm_put_kvm(stat_data
->kvm
);
3657 static int vm_stat_get_per_vm(void *data
, u64
*val
)
3659 struct kvm_stat_data
*stat_data
= (struct kvm_stat_data
*)data
;
3661 *val
= *(ulong
*)((void *)stat_data
->kvm
+ stat_data
->offset
);
3666 static int vm_stat_get_per_vm_open(struct inode
*inode
, struct file
*file
)
3668 __simple_attr_check_format("%llu\n", 0ull);
3669 return kvm_debugfs_open(inode
, file
, vm_stat_get_per_vm
,
3673 static const struct file_operations vm_stat_get_per_vm_fops
= {
3674 .owner
= THIS_MODULE
,
3675 .open
= vm_stat_get_per_vm_open
,
3676 .release
= kvm_debugfs_release
,
3677 .read
= simple_attr_read
,
3678 .write
= simple_attr_write
,
3679 .llseek
= generic_file_llseek
,
3682 static int vcpu_stat_get_per_vm(void *data
, u64
*val
)
3685 struct kvm_stat_data
*stat_data
= (struct kvm_stat_data
*)data
;
3686 struct kvm_vcpu
*vcpu
;
3690 kvm_for_each_vcpu(i
, vcpu
, stat_data
->kvm
)
3691 *val
+= *(u64
*)((void *)vcpu
+ stat_data
->offset
);
3696 static int vcpu_stat_get_per_vm_open(struct inode
*inode
, struct file
*file
)
3698 __simple_attr_check_format("%llu\n", 0ull);
3699 return kvm_debugfs_open(inode
, file
, vcpu_stat_get_per_vm
,
3703 static const struct file_operations vcpu_stat_get_per_vm_fops
= {
3704 .owner
= THIS_MODULE
,
3705 .open
= vcpu_stat_get_per_vm_open
,
3706 .release
= kvm_debugfs_release
,
3707 .read
= simple_attr_read
,
3708 .write
= simple_attr_write
,
3709 .llseek
= generic_file_llseek
,
3712 static const struct file_operations
*stat_fops_per_vm
[] = {
3713 [KVM_STAT_VCPU
] = &vcpu_stat_get_per_vm_fops
,
3714 [KVM_STAT_VM
] = &vm_stat_get_per_vm_fops
,
3717 static int vm_stat_get(void *_offset
, u64
*val
)
3719 unsigned offset
= (long)_offset
;
3721 struct kvm_stat_data stat_tmp
= {.offset
= offset
};
3725 spin_lock(&kvm_lock
);
3726 list_for_each_entry(kvm
, &vm_list
, vm_list
) {
3728 vm_stat_get_per_vm((void *)&stat_tmp
, &tmp_val
);
3731 spin_unlock(&kvm_lock
);
3735 DEFINE_SIMPLE_ATTRIBUTE(vm_stat_fops
, vm_stat_get
, NULL
, "%llu\n");
3737 static int vcpu_stat_get(void *_offset
, u64
*val
)
3739 unsigned offset
= (long)_offset
;
3741 struct kvm_stat_data stat_tmp
= {.offset
= offset
};
3745 spin_lock(&kvm_lock
);
3746 list_for_each_entry(kvm
, &vm_list
, vm_list
) {
3748 vcpu_stat_get_per_vm((void *)&stat_tmp
, &tmp_val
);
3751 spin_unlock(&kvm_lock
);
3755 DEFINE_SIMPLE_ATTRIBUTE(vcpu_stat_fops
, vcpu_stat_get
, NULL
, "%llu\n");
3757 static const struct file_operations
*stat_fops
[] = {
3758 [KVM_STAT_VCPU
] = &vcpu_stat_fops
,
3759 [KVM_STAT_VM
] = &vm_stat_fops
,
3762 static int kvm_init_debug(void)
3765 struct kvm_stats_debugfs_item
*p
;
3767 kvm_debugfs_dir
= debugfs_create_dir("kvm", NULL
);
3768 if (kvm_debugfs_dir
== NULL
)
3771 kvm_debugfs_num_entries
= 0;
3772 for (p
= debugfs_entries
; p
->name
; ++p
, kvm_debugfs_num_entries
++) {
3773 if (!debugfs_create_file(p
->name
, 0444, kvm_debugfs_dir
,
3774 (void *)(long)p
->offset
,
3775 stat_fops
[p
->kind
]))
3782 debugfs_remove_recursive(kvm_debugfs_dir
);
3787 static int kvm_suspend(void)
3789 if (kvm_usage_count
)
3790 hardware_disable_nolock(NULL
);
3794 static void kvm_resume(void)
3796 if (kvm_usage_count
) {
3797 WARN_ON(raw_spin_is_locked(&kvm_count_lock
));
3798 hardware_enable_nolock(NULL
);
3802 static struct syscore_ops kvm_syscore_ops
= {
3803 .suspend
= kvm_suspend
,
3804 .resume
= kvm_resume
,
3808 struct kvm_vcpu
*preempt_notifier_to_vcpu(struct preempt_notifier
*pn
)
3810 return container_of(pn
, struct kvm_vcpu
, preempt_notifier
);
3813 static void kvm_sched_in(struct preempt_notifier
*pn
, int cpu
)
3815 struct kvm_vcpu
*vcpu
= preempt_notifier_to_vcpu(pn
);
3817 if (vcpu
->preempted
)
3818 vcpu
->preempted
= false;
3820 kvm_arch_sched_in(vcpu
, cpu
);
3822 kvm_arch_vcpu_load(vcpu
, cpu
);
3825 static void kvm_sched_out(struct preempt_notifier
*pn
,
3826 struct task_struct
*next
)
3828 struct kvm_vcpu
*vcpu
= preempt_notifier_to_vcpu(pn
);
3830 if (current
->state
== TASK_RUNNING
)
3831 vcpu
->preempted
= true;
3832 kvm_arch_vcpu_put(vcpu
);
3835 int kvm_init(void *opaque
, unsigned vcpu_size
, unsigned vcpu_align
,
3836 struct module
*module
)
3841 r
= kvm_arch_init(opaque
);
3846 * kvm_arch_init makes sure there's at most one caller
3847 * for architectures that support multiple implementations,
3848 * like intel and amd on x86.
3851 if (!zalloc_cpumask_var(&cpus_hardware_enabled
, GFP_KERNEL
)) {
3856 r
= kvm_arch_hardware_setup();
3860 for_each_online_cpu(cpu
) {
3861 smp_call_function_single(cpu
,
3862 kvm_arch_check_processor_compat
,
3868 r
= cpuhp_setup_state_nocalls(CPUHP_AP_KVM_STARTING
, "AP_KVM_STARTING",
3869 kvm_starting_cpu
, kvm_dying_cpu
);
3872 register_reboot_notifier(&kvm_reboot_notifier
);
3874 /* A kmem cache lets us meet the alignment requirements of fx_save. */
3876 vcpu_align
= __alignof__(struct kvm_vcpu
);
3877 kvm_vcpu_cache
= kmem_cache_create("kvm_vcpu", vcpu_size
, vcpu_align
,
3879 if (!kvm_vcpu_cache
) {
3884 r
= kvm_async_pf_init();
3888 kvm_chardev_ops
.owner
= module
;
3889 kvm_vm_fops
.owner
= module
;
3890 kvm_vcpu_fops
.owner
= module
;
3892 r
= misc_register(&kvm_dev
);
3894 pr_err("kvm: misc device register failed\n");
3898 register_syscore_ops(&kvm_syscore_ops
);
3900 kvm_preempt_ops
.sched_in
= kvm_sched_in
;
3901 kvm_preempt_ops
.sched_out
= kvm_sched_out
;
3903 r
= kvm_init_debug();
3905 pr_err("kvm: create debugfs files failed\n");
3909 r
= kvm_vfio_ops_init();
3915 unregister_syscore_ops(&kvm_syscore_ops
);
3916 misc_deregister(&kvm_dev
);
3918 kvm_async_pf_deinit();
3920 kmem_cache_destroy(kvm_vcpu_cache
);
3922 unregister_reboot_notifier(&kvm_reboot_notifier
);
3923 cpuhp_remove_state_nocalls(CPUHP_AP_KVM_STARTING
);
3926 kvm_arch_hardware_unsetup();
3928 free_cpumask_var(cpus_hardware_enabled
);
3935 EXPORT_SYMBOL_GPL(kvm_init
);
3939 debugfs_remove_recursive(kvm_debugfs_dir
);
3940 misc_deregister(&kvm_dev
);
3941 kmem_cache_destroy(kvm_vcpu_cache
);
3942 kvm_async_pf_deinit();
3943 unregister_syscore_ops(&kvm_syscore_ops
);
3944 unregister_reboot_notifier(&kvm_reboot_notifier
);
3945 cpuhp_remove_state_nocalls(CPUHP_AP_KVM_STARTING
);
3946 on_each_cpu(hardware_disable_nolock
, NULL
, 1);
3947 kvm_arch_hardware_unsetup();
3950 free_cpumask_var(cpus_hardware_enabled
);
3951 kvm_vfio_ops_exit();
3953 EXPORT_SYMBOL_GPL(kvm_exit
);