5 * This work is licensed under the terms of the GNU GPL, version 2. See
6 * the COPYING file in the top-level directory.
9 #include <linux/types.h>
10 #include <linux/hardirq.h>
11 #include <linux/list.h>
12 #include <linux/mutex.h>
13 #include <linux/spinlock.h>
14 #include <linux/signal.h>
15 #include <linux/sched.h>
17 #include <linux/preempt.h>
18 #include <linux/msi.h>
19 #include <asm/signal.h>
21 #include <linux/kvm.h>
22 #include <linux/kvm_para.h>
24 #include <linux/kvm_types.h>
26 #include <asm/kvm_host.h>
29 * vcpu->requests bit members
31 #define KVM_REQ_TLB_FLUSH 0
32 #define KVM_REQ_MIGRATE_TIMER 1
33 #define KVM_REQ_REPORT_TPR_ACCESS 2
34 #define KVM_REQ_MMU_RELOAD 3
35 #define KVM_REQ_TRIPLE_FAULT 4
36 #define KVM_REQ_PENDING_TIMER 5
37 #define KVM_REQ_UNHALT 6
38 #define KVM_REQ_MMU_SYNC 7
39 #define KVM_REQ_CLOCK_UPDATE 8
40 #define KVM_REQ_KICK 9
41 #define KVM_REQ_DEACTIVATE_FPU 10
42 #define KVM_REQ_EVENT 11
43 #define KVM_REQ_APF_HALT 12
45 #define KVM_USERSPACE_IRQ_SOURCE_ID 0
49 extern struct kmem_cache *kvm_vcpu_cache;
52 * It would be nice to use something smarter than a linear search, TBD...
53 * Thankfully we dont expect many devices to register (famous last words :),
54 * so until then it will suffice. At least its abstracted so we can change
59 #define NR_IOBUS_DEVS 200
60 struct kvm_io_device *devs[NR_IOBUS_DEVS];
69 int kvm_io_bus_write(struct kvm *kvm, enum kvm_bus bus_idx, gpa_t addr,
70 int len, const void *val);
71 int kvm_io_bus_read(struct kvm *kvm, enum kvm_bus bus_idx, gpa_t addr, int len,
73 int kvm_io_bus_register_dev(struct kvm *kvm, enum kvm_bus bus_idx,
74 struct kvm_io_device *dev);
75 int kvm_io_bus_unregister_dev(struct kvm *kvm, enum kvm_bus bus_idx,
76 struct kvm_io_device *dev);
78 #ifdef CONFIG_KVM_ASYNC_PF
80 struct work_struct work;
81 struct list_head link;
82 struct list_head queue;
83 struct kvm_vcpu *vcpu;
87 struct kvm_arch_async_pf arch;
92 void kvm_clear_async_pf_completion_queue(struct kvm_vcpu *vcpu);
93 void kvm_check_async_pf_completion(struct kvm_vcpu *vcpu);
94 int kvm_setup_async_pf(struct kvm_vcpu *vcpu, gva_t gva, gfn_t gfn,
95 struct kvm_arch_async_pf *arch);
96 int kvm_async_pf_wakeup_all(struct kvm_vcpu *vcpu);
101 #ifdef CONFIG_PREEMPT_NOTIFIERS
102 struct preempt_notifier preempt_notifier;
109 unsigned long requests;
110 unsigned long guest_debug;
114 int guest_fpu_loaded, guest_xcr0_loaded;
115 wait_queue_head_t wq;
118 struct kvm_vcpu_stat stat;
120 #ifdef CONFIG_HAS_IOMEM
122 int mmio_read_completed;
125 unsigned char mmio_data[8];
126 gpa_t mmio_phys_addr;
129 #ifdef CONFIG_KVM_ASYNC_PF
132 struct list_head queue;
133 struct list_head done;
138 struct kvm_vcpu_arch arch;
142 * Some of the bitops functions do not support too long bitmaps.
143 * This number must be determined not to exceed such limits.
145 #define KVM_MEM_MAX_NR_PAGES ((1UL << 31) - 1)
147 struct kvm_memory_slot {
149 unsigned long npages;
152 unsigned long *dirty_bitmap;
154 unsigned long rmap_pde;
156 } *lpage_info[KVM_NR_PAGE_SIZES - 1];
157 unsigned long userspace_addr;
162 static inline unsigned long kvm_dirty_bitmap_bytes(struct kvm_memory_slot *memslot)
164 return ALIGN(memslot->npages, BITS_PER_LONG) / 8;
167 struct kvm_kernel_irq_routing_entry {
170 int (*set)(struct kvm_kernel_irq_routing_entry *e,
171 struct kvm *kvm, int irq_source_id, int level);
179 struct hlist_node link;
182 #ifdef __KVM_HAVE_IOAPIC
184 struct kvm_irq_routing_table {
185 int chip[KVM_NR_IRQCHIPS][KVM_IOAPIC_NUM_PINS];
186 struct kvm_kernel_irq_routing_entry *rt_entries;
189 * Array indexed by gsi. Each entry contains list of irq chips
190 * the gsi is connected to.
192 struct hlist_head map[0];
197 struct kvm_irq_routing_table {};
201 struct kvm_memslots {
204 struct kvm_memory_slot memslots[KVM_MEMORY_SLOTS +
205 KVM_PRIVATE_MEM_SLOTS];
210 raw_spinlock_t requests_lock;
211 struct mutex slots_lock;
212 struct mm_struct *mm; /* userspace tied to this vm */
213 struct kvm_memslots *memslots;
214 struct srcu_struct srcu;
215 #ifdef CONFIG_KVM_APIC_ARCHITECTURE
217 struct kvm_vcpu *bsp_vcpu;
219 struct kvm_vcpu *vcpus[KVM_MAX_VCPUS];
220 atomic_t online_vcpus;
221 struct list_head vm_list;
223 struct kvm_io_bus *buses[KVM_NR_BUSES];
224 #ifdef CONFIG_HAVE_KVM_EVENTFD
227 struct list_head items;
229 struct list_head ioeventfds;
231 struct kvm_vm_stat stat;
232 struct kvm_arch arch;
233 atomic_t users_count;
234 #ifdef KVM_COALESCED_MMIO_PAGE_OFFSET
235 struct kvm_coalesced_mmio_dev *coalesced_mmio_dev;
236 struct kvm_coalesced_mmio_ring *coalesced_mmio_ring;
239 struct mutex irq_lock;
240 #ifdef CONFIG_HAVE_KVM_IRQCHIP
241 struct kvm_irq_routing_table __rcu *irq_routing;
242 struct hlist_head mask_notifier_list;
243 struct hlist_head irq_ack_notifier_list;
246 #ifdef KVM_ARCH_WANT_MMU_NOTIFIER
247 struct mmu_notifier mmu_notifier;
248 unsigned long mmu_notifier_seq;
249 long mmu_notifier_count;
253 /* The guest did something we don't support. */
254 #define pr_unimpl(vcpu, fmt, ...) \
256 if (printk_ratelimit()) \
257 printk(KERN_ERR "kvm: %i: cpu%i " fmt, \
258 current->tgid, (vcpu)->vcpu_id , ## __VA_ARGS__); \
261 #define kvm_printf(kvm, fmt ...) printk(KERN_DEBUG fmt)
262 #define vcpu_printf(vcpu, fmt...) kvm_printf(vcpu->kvm, fmt)
264 static inline struct kvm_vcpu *kvm_get_vcpu(struct kvm *kvm, int i)
267 return kvm->vcpus[i];
270 #define kvm_for_each_vcpu(idx, vcpup, kvm) \
271 for (idx = 0, vcpup = kvm_get_vcpu(kvm, idx); \
272 idx < atomic_read(&kvm->online_vcpus) && vcpup; \
273 vcpup = kvm_get_vcpu(kvm, ++idx))
275 int kvm_vcpu_init(struct kvm_vcpu *vcpu, struct kvm *kvm, unsigned id);
276 void kvm_vcpu_uninit(struct kvm_vcpu *vcpu);
278 void vcpu_load(struct kvm_vcpu *vcpu);
279 void vcpu_put(struct kvm_vcpu *vcpu);
281 int kvm_init(void *opaque, unsigned vcpu_size, unsigned vcpu_align,
282 struct module *module);
285 void kvm_get_kvm(struct kvm *kvm);
286 void kvm_put_kvm(struct kvm *kvm);
288 static inline struct kvm_memslots *kvm_memslots(struct kvm *kvm)
290 return rcu_dereference_check(kvm->memslots,
291 srcu_read_lock_held(&kvm->srcu)
292 || lockdep_is_held(&kvm->slots_lock));
295 #define HPA_MSB ((sizeof(hpa_t) * 8) - 1)
296 #define HPA_ERR_MASK ((hpa_t)1 << HPA_MSB)
297 static inline int is_error_hpa(hpa_t hpa) { return hpa >> HPA_MSB; }
299 extern struct page *bad_page;
300 extern pfn_t bad_pfn;
302 int is_error_page(struct page *page);
303 int is_error_pfn(pfn_t pfn);
304 int is_hwpoison_pfn(pfn_t pfn);
305 int is_fault_pfn(pfn_t pfn);
306 int kvm_is_error_hva(unsigned long addr);
307 int kvm_set_memory_region(struct kvm *kvm,
308 struct kvm_userspace_memory_region *mem,
310 int __kvm_set_memory_region(struct kvm *kvm,
311 struct kvm_userspace_memory_region *mem,
313 int kvm_arch_prepare_memory_region(struct kvm *kvm,
314 struct kvm_memory_slot *memslot,
315 struct kvm_memory_slot old,
316 struct kvm_userspace_memory_region *mem,
318 void kvm_arch_commit_memory_region(struct kvm *kvm,
319 struct kvm_userspace_memory_region *mem,
320 struct kvm_memory_slot old,
322 void kvm_disable_largepages(void);
323 void kvm_arch_flush_shadow(struct kvm *kvm);
325 int gfn_to_page_many_atomic(struct kvm *kvm, gfn_t gfn, struct page **pages,
328 struct page *gfn_to_page(struct kvm *kvm, gfn_t gfn);
329 unsigned long gfn_to_hva(struct kvm *kvm, gfn_t gfn);
330 void kvm_release_page_clean(struct page *page);
331 void kvm_release_page_dirty(struct page *page);
332 void kvm_set_page_dirty(struct page *page);
333 void kvm_set_page_accessed(struct page *page);
335 pfn_t hva_to_pfn_atomic(struct kvm *kvm, unsigned long addr);
336 pfn_t gfn_to_pfn_atomic(struct kvm *kvm, gfn_t gfn);
337 pfn_t gfn_to_pfn_async(struct kvm *kvm, gfn_t gfn, bool *async,
338 bool write_fault, bool *writable);
339 pfn_t gfn_to_pfn(struct kvm *kvm, gfn_t gfn);
340 pfn_t gfn_to_pfn_prot(struct kvm *kvm, gfn_t gfn, bool write_fault,
342 pfn_t gfn_to_pfn_memslot(struct kvm *kvm,
343 struct kvm_memory_slot *slot, gfn_t gfn);
344 int memslot_id(struct kvm *kvm, gfn_t gfn);
345 void kvm_release_pfn_dirty(pfn_t);
346 void kvm_release_pfn_clean(pfn_t pfn);
347 void kvm_set_pfn_dirty(pfn_t pfn);
348 void kvm_set_pfn_accessed(pfn_t pfn);
349 void kvm_get_pfn(pfn_t pfn);
351 int kvm_read_guest_page(struct kvm *kvm, gfn_t gfn, void *data, int offset,
353 int kvm_read_guest_atomic(struct kvm *kvm, gpa_t gpa, void *data,
355 int kvm_read_guest(struct kvm *kvm, gpa_t gpa, void *data, unsigned long len);
356 int kvm_write_guest_page(struct kvm *kvm, gfn_t gfn, const void *data,
357 int offset, int len);
358 int kvm_write_guest(struct kvm *kvm, gpa_t gpa, const void *data,
360 int kvm_write_guest_cached(struct kvm *kvm, struct gfn_to_hva_cache *ghc,
361 void *data, unsigned long len);
362 int kvm_gfn_to_hva_cache_init(struct kvm *kvm, struct gfn_to_hva_cache *ghc,
364 int kvm_clear_guest_page(struct kvm *kvm, gfn_t gfn, int offset, int len);
365 int kvm_clear_guest(struct kvm *kvm, gpa_t gpa, unsigned long len);
366 struct kvm_memory_slot *gfn_to_memslot(struct kvm *kvm, gfn_t gfn);
367 int kvm_is_visible_gfn(struct kvm *kvm, gfn_t gfn);
368 unsigned long kvm_host_page_size(struct kvm *kvm, gfn_t gfn);
369 void mark_page_dirty(struct kvm *kvm, gfn_t gfn);
370 void mark_page_dirty_in_slot(struct kvm *kvm, struct kvm_memory_slot *memslot,
373 void kvm_vcpu_block(struct kvm_vcpu *vcpu);
374 void kvm_vcpu_on_spin(struct kvm_vcpu *vcpu);
375 void kvm_resched(struct kvm_vcpu *vcpu);
376 void kvm_load_guest_fpu(struct kvm_vcpu *vcpu);
377 void kvm_put_guest_fpu(struct kvm_vcpu *vcpu);
378 void kvm_flush_remote_tlbs(struct kvm *kvm);
379 void kvm_reload_remote_mmus(struct kvm *kvm);
381 long kvm_arch_dev_ioctl(struct file *filp,
382 unsigned int ioctl, unsigned long arg);
383 long kvm_arch_vcpu_ioctl(struct file *filp,
384 unsigned int ioctl, unsigned long arg);
386 int kvm_dev_ioctl_check_extension(long ext);
388 int kvm_get_dirty_log(struct kvm *kvm,
389 struct kvm_dirty_log *log, int *is_dirty);
390 int kvm_vm_ioctl_get_dirty_log(struct kvm *kvm,
391 struct kvm_dirty_log *log);
393 int kvm_vm_ioctl_set_memory_region(struct kvm *kvm,
395 kvm_userspace_memory_region *mem,
397 long kvm_arch_vm_ioctl(struct file *filp,
398 unsigned int ioctl, unsigned long arg);
400 int kvm_arch_vcpu_ioctl_get_fpu(struct kvm_vcpu *vcpu, struct kvm_fpu *fpu);
401 int kvm_arch_vcpu_ioctl_set_fpu(struct kvm_vcpu *vcpu, struct kvm_fpu *fpu);
403 int kvm_arch_vcpu_ioctl_translate(struct kvm_vcpu *vcpu,
404 struct kvm_translation *tr);
406 int kvm_arch_vcpu_ioctl_get_regs(struct kvm_vcpu *vcpu, struct kvm_regs *regs);
407 int kvm_arch_vcpu_ioctl_set_regs(struct kvm_vcpu *vcpu, struct kvm_regs *regs);
408 int kvm_arch_vcpu_ioctl_get_sregs(struct kvm_vcpu *vcpu,
409 struct kvm_sregs *sregs);
410 int kvm_arch_vcpu_ioctl_set_sregs(struct kvm_vcpu *vcpu,
411 struct kvm_sregs *sregs);
412 int kvm_arch_vcpu_ioctl_get_mpstate(struct kvm_vcpu *vcpu,
413 struct kvm_mp_state *mp_state);
414 int kvm_arch_vcpu_ioctl_set_mpstate(struct kvm_vcpu *vcpu,
415 struct kvm_mp_state *mp_state);
416 int kvm_arch_vcpu_ioctl_set_guest_debug(struct kvm_vcpu *vcpu,
417 struct kvm_guest_debug *dbg);
418 int kvm_arch_vcpu_ioctl_run(struct kvm_vcpu *vcpu, struct kvm_run *kvm_run);
420 int kvm_arch_init(void *opaque);
421 void kvm_arch_exit(void);
423 int kvm_arch_vcpu_init(struct kvm_vcpu *vcpu);
424 void kvm_arch_vcpu_uninit(struct kvm_vcpu *vcpu);
426 void kvm_arch_vcpu_free(struct kvm_vcpu *vcpu);
427 void kvm_arch_vcpu_load(struct kvm_vcpu *vcpu, int cpu);
428 void kvm_arch_vcpu_put(struct kvm_vcpu *vcpu);
429 struct kvm_vcpu *kvm_arch_vcpu_create(struct kvm *kvm, unsigned int id);
430 int kvm_arch_vcpu_setup(struct kvm_vcpu *vcpu);
431 void kvm_arch_vcpu_destroy(struct kvm_vcpu *vcpu);
433 int kvm_arch_vcpu_reset(struct kvm_vcpu *vcpu);
434 int kvm_arch_hardware_enable(void *garbage);
435 void kvm_arch_hardware_disable(void *garbage);
436 int kvm_arch_hardware_setup(void);
437 void kvm_arch_hardware_unsetup(void);
438 void kvm_arch_check_processor_compat(void *rtn);
439 int kvm_arch_vcpu_runnable(struct kvm_vcpu *vcpu);
441 void kvm_free_physmem(struct kvm *kvm);
443 struct kvm *kvm_arch_create_vm(void);
444 void kvm_arch_destroy_vm(struct kvm *kvm);
445 void kvm_free_all_assigned_devices(struct kvm *kvm);
446 void kvm_arch_sync_events(struct kvm *kvm);
448 int kvm_cpu_has_pending_timer(struct kvm_vcpu *vcpu);
449 void kvm_vcpu_kick(struct kvm_vcpu *vcpu);
451 int kvm_is_mmio_pfn(pfn_t pfn);
453 struct kvm_irq_ack_notifier {
454 struct hlist_node link;
456 void (*irq_acked)(struct kvm_irq_ack_notifier *kian);
459 #define KVM_ASSIGNED_MSIX_PENDING 0x1
460 struct kvm_guest_msix_entry {
466 struct kvm_assigned_dev_kernel {
467 struct kvm_irq_ack_notifier ack_notifier;
468 struct work_struct interrupt_work;
469 struct list_head list;
474 unsigned int entries_nr;
476 bool host_irq_disabled;
477 struct msix_entry *host_msix_entries;
479 struct kvm_guest_msix_entry *guest_msix_entries;
480 unsigned long irq_requested_type;
485 spinlock_t assigned_dev_lock;
488 struct kvm_irq_mask_notifier {
489 void (*func)(struct kvm_irq_mask_notifier *kimn, bool masked);
491 struct hlist_node link;
494 void kvm_register_irq_mask_notifier(struct kvm *kvm, int irq,
495 struct kvm_irq_mask_notifier *kimn);
496 void kvm_unregister_irq_mask_notifier(struct kvm *kvm, int irq,
497 struct kvm_irq_mask_notifier *kimn);
498 void kvm_fire_mask_notifiers(struct kvm *kvm, unsigned irqchip, unsigned pin,
501 #ifdef __KVM_HAVE_IOAPIC
502 void kvm_get_intr_delivery_bitmask(struct kvm_ioapic *ioapic,
503 union kvm_ioapic_redirect_entry *entry,
504 unsigned long *deliver_bitmask);
506 int kvm_set_irq(struct kvm *kvm, int irq_source_id, u32 irq, int level);
507 void kvm_notify_acked_irq(struct kvm *kvm, unsigned irqchip, unsigned pin);
508 void kvm_register_irq_ack_notifier(struct kvm *kvm,
509 struct kvm_irq_ack_notifier *kian);
510 void kvm_unregister_irq_ack_notifier(struct kvm *kvm,
511 struct kvm_irq_ack_notifier *kian);
512 int kvm_request_irq_source_id(struct kvm *kvm);
513 void kvm_free_irq_source_id(struct kvm *kvm, int irq_source_id);
515 /* For vcpu->arch.iommu_flags */
516 #define KVM_IOMMU_CACHE_COHERENCY 0x1
518 #ifdef CONFIG_IOMMU_API
519 int kvm_iommu_map_pages(struct kvm *kvm, struct kvm_memory_slot *slot);
520 int kvm_iommu_map_guest(struct kvm *kvm);
521 int kvm_iommu_unmap_guest(struct kvm *kvm);
522 int kvm_assign_device(struct kvm *kvm,
523 struct kvm_assigned_dev_kernel *assigned_dev);
524 int kvm_deassign_device(struct kvm *kvm,
525 struct kvm_assigned_dev_kernel *assigned_dev);
526 #else /* CONFIG_IOMMU_API */
527 static inline int kvm_iommu_map_pages(struct kvm *kvm,
528 struct kvm_memory_slot *slot)
533 static inline int kvm_iommu_map_guest(struct kvm *kvm)
538 static inline int kvm_iommu_unmap_guest(struct kvm *kvm)
543 static inline int kvm_assign_device(struct kvm *kvm,
544 struct kvm_assigned_dev_kernel *assigned_dev)
549 static inline int kvm_deassign_device(struct kvm *kvm,
550 struct kvm_assigned_dev_kernel *assigned_dev)
554 #endif /* CONFIG_IOMMU_API */
556 static inline void kvm_guest_enter(void)
558 account_system_vtime(current);
559 current->flags |= PF_VCPU;
562 static inline void kvm_guest_exit(void)
564 account_system_vtime(current);
565 current->flags &= ~PF_VCPU;
568 static inline unsigned long gfn_to_hva_memslot(struct kvm_memory_slot *slot,
571 return slot->userspace_addr + (gfn - slot->base_gfn) * PAGE_SIZE;
574 static inline gpa_t gfn_to_gpa(gfn_t gfn)
576 return (gpa_t)gfn << PAGE_SHIFT;
579 static inline gfn_t gpa_to_gfn(gpa_t gpa)
581 return (gfn_t)(gpa >> PAGE_SHIFT);
584 static inline hpa_t pfn_to_hpa(pfn_t pfn)
586 return (hpa_t)pfn << PAGE_SHIFT;
589 static inline void kvm_migrate_timers(struct kvm_vcpu *vcpu)
591 set_bit(KVM_REQ_MIGRATE_TIMER, &vcpu->requests);
599 struct kvm_stats_debugfs_item {
602 enum kvm_stat_kind kind;
603 struct dentry *dentry;
605 extern struct kvm_stats_debugfs_item debugfs_entries[];
606 extern struct dentry *kvm_debugfs_dir;
608 #ifdef KVM_ARCH_WANT_MMU_NOTIFIER
609 static inline int mmu_notifier_retry(struct kvm_vcpu *vcpu, unsigned long mmu_seq)
611 if (unlikely(vcpu->kvm->mmu_notifier_count))
614 * Both reads happen under the mmu_lock and both values are
615 * modified under mmu_lock, so there's no need of smb_rmb()
616 * here in between, otherwise mmu_notifier_count should be
617 * read before mmu_notifier_seq, see
618 * mmu_notifier_invalidate_range_end write side.
620 if (vcpu->kvm->mmu_notifier_seq != mmu_seq)
626 #ifdef CONFIG_HAVE_KVM_IRQCHIP
628 #define KVM_MAX_IRQ_ROUTES 1024
630 int kvm_setup_default_irq_routing(struct kvm *kvm);
631 int kvm_set_irq_routing(struct kvm *kvm,
632 const struct kvm_irq_routing_entry *entries,
635 void kvm_free_irq_routing(struct kvm *kvm);
639 static inline void kvm_free_irq_routing(struct kvm *kvm) {}
643 #ifdef CONFIG_HAVE_KVM_EVENTFD
645 void kvm_eventfd_init(struct kvm *kvm);
646 int kvm_irqfd(struct kvm *kvm, int fd, int gsi, int flags);
647 void kvm_irqfd_release(struct kvm *kvm);
648 int kvm_ioeventfd(struct kvm *kvm, struct kvm_ioeventfd *args);
652 static inline void kvm_eventfd_init(struct kvm *kvm) {}
653 static inline int kvm_irqfd(struct kvm *kvm, int fd, int gsi, int flags)
658 static inline void kvm_irqfd_release(struct kvm *kvm) {}
659 static inline int kvm_ioeventfd(struct kvm *kvm, struct kvm_ioeventfd *args)
664 #endif /* CONFIG_HAVE_KVM_EVENTFD */
666 #ifdef CONFIG_KVM_APIC_ARCHITECTURE
667 static inline bool kvm_vcpu_is_bsp(struct kvm_vcpu *vcpu)
669 return vcpu->kvm->bsp_vcpu_id == vcpu->vcpu_id;
673 #ifdef __KVM_HAVE_DEVICE_ASSIGNMENT
675 long kvm_vm_ioctl_assigned_device(struct kvm *kvm, unsigned ioctl,
680 static inline long kvm_vm_ioctl_assigned_device(struct kvm *kvm, unsigned ioctl,
688 static inline void kvm_make_request(int req, struct kvm_vcpu *vcpu)
690 set_bit(req, &vcpu->requests);
693 static inline bool kvm_make_check_request(int req, struct kvm_vcpu *vcpu)
695 return test_and_set_bit(req, &vcpu->requests);
698 static inline bool kvm_check_request(int req, struct kvm_vcpu *vcpu)
700 if (test_bit(req, &vcpu->requests)) {
701 clear_bit(req, &vcpu->requests);