virt/kvm/kvm_main.c

   1 /*
   2  * Kernel-based Virtual Machine driver for Linux
   3  *
   4  * This module enables machines with Intel VT-x extensions to run virtual
   5  * machines without emulation or binary translation.
   6  *
   7  * Copyright (C) 2006 Qumranet, Inc.
   8  * Copyright 2010 Red Hat, Inc. and/or its affiliates.
   9  *
  10  * Authors:
  11  *   Avi Kivity   <avi@qumranet.com>
  12  *   Yaniv Kamay  <yaniv@qumranet.com>
  13  *
  14  * This work is licensed under the terms of the GNU GPL, version 2.  See
  15  * the COPYING file in the top-level directory.
  16  *
  17  */
  18
  19 #include "iodev.h"
  20
  21 #include <linux/kvm_host.h>
  22 #include <linux/kvm.h>
  23 #include <linux/module.h>
  24 #include <linux/errno.h>
  25 #include <linux/percpu.h>
  26 #include <linux/mm.h>
  27 #include <linux/miscdevice.h>
  28 #include <linux/vmalloc.h>
  29 #include <linux/reboot.h>
  30 #include <linux/debugfs.h>
  31 #include <linux/highmem.h>
  32 #include <linux/file.h>
  33 #include <linux/syscore_ops.h>
  34 #include <linux/cpu.h>
  35 #include <linux/sched.h>
  36 #include <linux/cpumask.h>
  37 #include <linux/smp.h>
  38 #include <linux/anon_inodes.h>
  39 #include <linux/profile.h>
  40 #include <linux/kvm_para.h>
  41 #include <linux/pagemap.h>
  42 #include <linux/mman.h>
  43 #include <linux/swap.h>
  44 #include <linux/bitops.h>
  45 #include <linux/spinlock.h>
  46 #include <linux/compat.h>
  47 #include <linux/srcu.h>
  48 #include <linux/hugetlb.h>
  49 #include <linux/slab.h>
  50 #include <linux/sort.h>
  51 #include <linux/bsearch.h>
  52
  53 #include <asm/processor.h>
  54 #include <asm/io.h>
  55 #include <asm/uaccess.h>
  56 #include <asm/pgtable.h>
  57
  58 #include "coalesced_mmio.h"
  59 #include "async_pf.h"
  60
  61 #define CREATE_TRACE_POINTS
  62 #include <trace/events/kvm.h>
  63
  64 MODULE_AUTHOR("Qumranet");
  65 MODULE_LICENSE("GPL");
  66
  67 /*
  68  * Ordering of locks:
  69  *
  70  *              kvm->lock --> kvm->slots_lock --> kvm->irq_lock
  71  */
  72
  73 DEFINE_RAW_SPINLOCK(kvm_lock);
  74 LIST_HEAD(vm_list);
  75
  76 static cpumask_var_t cpus_hardware_enabled;
  77 static int kvm_usage_count = 0;
  78 static atomic_t hardware_enable_failed;
  79
  80 struct kmem_cache *kvm_vcpu_cache;
  81 EXPORT_SYMBOL_GPL(kvm_vcpu_cache);
  82
  83 static __read_mostly struct preempt_ops kvm_preempt_ops;
  84
  85 struct dentry *kvm_debugfs_dir;
  86
  87 static long kvm_vcpu_ioctl(struct file *file, unsigned int ioctl,
  88                            unsigned long arg);
  89 #ifdef CONFIG_COMPAT
  90 static long kvm_vcpu_compat_ioctl(struct file *file, unsigned int ioctl,
  91                                   unsigned long arg);
  92 #endif
  93 static int hardware_enable_all(void);
  94 static void hardware_disable_all(void);
  95
  96 static void kvm_io_bus_destroy(struct kvm_io_bus *bus);
  97
  98 bool kvm_rebooting;
  99 EXPORT_SYMBOL_GPL(kvm_rebooting);
 100
 101 static bool largepages_enabled = true;
 102
 103 bool kvm_is_mmio_pfn(pfn_t pfn)
 104 {
 105         if (pfn_valid(pfn))
 106                 return PageReserved(pfn_to_page(pfn));
 107
 108         return true;
 109 }
 110
 111 /*
 112  * Switches to specified vcpu, until a matching vcpu_put()
 113  */
 114 int vcpu_load(struct kvm_vcpu *vcpu)
 115 {
 116         int cpu;
 117
 118         if (mutex_lock_killable(&vcpu->mutex))
 119                 return -EINTR;
 120         if (unlikely(vcpu->pid != current->pids[PIDTYPE_PID].pid)) {
 121                 /* The thread running this VCPU changed. */
 122                 struct pid *oldpid = vcpu->pid;
 123                 struct pid *newpid = get_task_pid(current, PIDTYPE_PID);
 124                 rcu_assign_pointer(vcpu->pid, newpid);
 125                 synchronize_rcu();
 126                 put_pid(oldpid);
 127         }
 128         cpu = get_cpu();
 129         preempt_notifier_register(&vcpu->preempt_notifier);
 130         kvm_arch_vcpu_load(vcpu, cpu);
 131         put_cpu();
 132         return 0;
 133 }
 134
 135 void vcpu_put(struct kvm_vcpu *vcpu)
 136 {
 137         preempt_disable();
 138         kvm_arch_vcpu_put(vcpu);
 139         preempt_notifier_unregister(&vcpu->preempt_notifier);
 140         preempt_enable();
 141         mutex_unlock(&vcpu->mutex);
 142 }
 143
 144 static void ack_flush(void *_completed)
 145 {
 146 }
 147
 148 static bool make_all_cpus_request(struct kvm *kvm, unsigned int req)
 149 {
 150         int i, cpu, me;
 151         cpumask_var_t cpus;
 152         bool called = true;
 153         struct kvm_vcpu *vcpu;
 154
 155         zalloc_cpumask_var(&cpus, GFP_ATOMIC);
 156
 157         me = get_cpu();
 158         kvm_for_each_vcpu(i, vcpu, kvm) {
 159                 kvm_make_request(req, vcpu);
 160                 cpu = vcpu->cpu;
 161
 162                 /* Set ->requests bit before we read ->mode */
 163                 smp_mb();
 164
 165                 if (cpus != NULL && cpu != -1 && cpu != me &&
 166                       kvm_vcpu_exiting_guest_mode(vcpu) != OUTSIDE_GUEST_MODE)
 167                         cpumask_set_cpu(cpu, cpus);
 168         }
 169         if (unlikely(cpus == NULL))
 170                 smp_call_function_many(cpu_online_mask, ack_flush, NULL, 1);
 171         else if (!cpumask_empty(cpus))
 172                 smp_call_function_many(cpus, ack_flush, NULL, 1);
 173         else
 174                 called = false;
 175         put_cpu();
 176         free_cpumask_var(cpus);
 177         return called;
 178 }
 179
 180 void kvm_flush_remote_tlbs(struct kvm *kvm)
 181 {
 182         long dirty_count = kvm->tlbs_dirty;
 183
 184         smp_mb();
 185         if (make_all_cpus_request(kvm, KVM_REQ_TLB_FLUSH))
 186                 ++kvm->stat.remote_tlb_flush;
 187         cmpxchg(&kvm->tlbs_dirty, dirty_count, 0);
 188 }
 189
 190 void kvm_reload_remote_mmus(struct kvm *kvm)
 191 {
 192         make_all_cpus_request(kvm, KVM_REQ_MMU_RELOAD);
 193 }
 194
 195 void kvm_make_mclock_inprogress_request(struct kvm *kvm)
 196 {
 197         make_all_cpus_request(kvm, KVM_REQ_MCLOCK_INPROGRESS);
 198 }
 199
 200 void kvm_make_scan_ioapic_request(struct kvm *kvm)
 201 {
 202         make_all_cpus_request(kvm, KVM_REQ_SCAN_IOAPIC);
 203 }
 204
 205 int kvm_vcpu_init(struct kvm_vcpu *vcpu, struct kvm *kvm, unsigned id)
 206 {
 207         struct page *page;
 208         int r;
 209
 210         mutex_init(&vcpu->mutex);
 211         vcpu->cpu = -1;
 212         vcpu->kvm = kvm;
 213         vcpu->vcpu_id = id;
 214         vcpu->pid = NULL;
 215         init_waitqueue_head(&vcpu->wq);
 216         kvm_async_pf_vcpu_init(vcpu);
 217
 218         page = alloc_page(GFP_KERNEL | __GFP_ZERO);
 219         if (!page) {
 220                 r = -ENOMEM;
 221                 goto fail;
 222         }
 223         vcpu->run = page_address(page);
 224
 225         kvm_vcpu_set_in_spin_loop(vcpu, false);
 226         kvm_vcpu_set_dy_eligible(vcpu, false);
 227         vcpu->preempted = false;
 228
 229         r = kvm_arch_vcpu_init(vcpu);
 230         if (r < 0)
 231                 goto fail_free_run;
 232         return 0;
 233
 234 fail_free_run:
 235         free_page((unsigned long)vcpu->run);
 236 fail:
 237         return r;
 238 }
 239 EXPORT_SYMBOL_GPL(kvm_vcpu_init);
 240
 241 void kvm_vcpu_uninit(struct kvm_vcpu *vcpu)
 242 {
 243         put_pid(vcpu->pid);
 244         kvm_arch_vcpu_uninit(vcpu);
 245         free_page((unsigned long)vcpu->run);
 246 }
 247 EXPORT_SYMBOL_GPL(kvm_vcpu_uninit);
 248
 249 #if defined(CONFIG_MMU_NOTIFIER) && defined(KVM_ARCH_WANT_MMU_NOTIFIER)
 250 static inline struct kvm *mmu_notifier_to_kvm(struct mmu_notifier *mn)
 251 {
 252         return container_of(mn, struct kvm, mmu_notifier);
 253 }
 254
 255 static void kvm_mmu_notifier_invalidate_page(struct mmu_notifier *mn,
 256                                              struct mm_struct *mm,
 257                                              unsigned long address)
 258 {
 259         struct kvm *kvm = mmu_notifier_to_kvm(mn);
 260         int need_tlb_flush, idx;
 261
 262         /*
 263          * When ->invalidate_page runs, the linux pte has been zapped
 264          * already but the page is still allocated until
 265          * ->invalidate_page returns. So if we increase the sequence
 266          * here the kvm page fault will notice if the spte can't be
 267          * established because the page is going to be freed. If
 268          * instead the kvm page fault establishes the spte before
 269          * ->invalidate_page runs, kvm_unmap_hva will release it
 270          * before returning.
 271          *
 272          * The sequence increase only need to be seen at spin_unlock
 273          * time, and not at spin_lock time.
 274          *
 275          * Increasing the sequence after the spin_unlock would be
 276          * unsafe because the kvm page fault could then establish the
 277          * pte after kvm_unmap_hva returned, without noticing the page
 278          * is going to be freed.
 279          */
 280         idx = srcu_read_lock(&kvm->srcu);
 281         spin_lock(&kvm->mmu_lock);
 282
 283         kvm->mmu_notifier_seq++;
 284         need_tlb_flush = kvm_unmap_hva(kvm, address) | kvm->tlbs_dirty;
 285         /* we've to flush the tlb before the pages can be freed */
 286         if (need_tlb_flush)
 287                 kvm_flush_remote_tlbs(kvm);
 288
 289         spin_unlock(&kvm->mmu_lock);
 290         srcu_read_unlock(&kvm->srcu, idx);
 291 }
 292
 293 static void kvm_mmu_notifier_change_pte(struct mmu_notifier *mn,
 294                                         struct mm_struct *mm,
 295                                         unsigned long address,
 296                                         pte_t pte)
 297 {
 298         struct kvm *kvm = mmu_notifier_to_kvm(mn);
 299         int idx;
 300
 301         idx = srcu_read_lock(&kvm->srcu);
 302         spin_lock(&kvm->mmu_lock);
 303         kvm->mmu_notifier_seq++;
 304         kvm_set_spte_hva(kvm, address, pte);
 305         spin_unlock(&kvm->mmu_lock);
 306         srcu_read_unlock(&kvm->srcu, idx);
 307 }
 308
 309 static void kvm_mmu_notifier_invalidate_range_start(struct mmu_notifier *mn,
 310                                                     struct mm_struct *mm,
 311                                                     unsigned long start,
 312                                                     unsigned long end)
 313 {
 314         struct kvm *kvm = mmu_notifier_to_kvm(mn);
 315         int need_tlb_flush = 0, idx;
 316
 317         idx = srcu_read_lock(&kvm->srcu);
 318         spin_lock(&kvm->mmu_lock);
 319         /*
 320          * The count increase must become visible at unlock time as no
 321          * spte can be established without taking the mmu_lock and
 322          * count is also read inside the mmu_lock critical section.
 323          */
 324         kvm->mmu_notifier_count++;
 325         need_tlb_flush = kvm_unmap_hva_range(kvm, start, end);
 326         need_tlb_flush |= kvm->tlbs_dirty;
 327         /* we've to flush the tlb before the pages can be freed */
 328         if (need_tlb_flush)
 329                 kvm_flush_remote_tlbs(kvm);
 330
 331         spin_unlock(&kvm->mmu_lock);
 332         srcu_read_unlock(&kvm->srcu, idx);
 333 }
 334
 335 static void kvm_mmu_notifier_invalidate_range_end(struct mmu_notifier *mn,
 336                                                   struct mm_struct *mm,
 337                                                   unsigned long start,
 338                                                   unsigned long end)
 339 {
 340         struct kvm *kvm = mmu_notifier_to_kvm(mn);
 341
 342         spin_lock(&kvm->mmu_lock);
 343         /*
 344          * This sequence increase will notify the kvm page fault that
 345          * the page that is going to be mapped in the spte could have
 346          * been freed.
 347          */
 348         kvm->mmu_notifier_seq++;
 349         smp_wmb();
 350         /*
 351          * The above sequence increase must be visible before the
 352          * below count decrease, which is ensured by the smp_wmb above
 353          * in conjunction with the smp_rmb in mmu_notifier_retry().
 354          */
 355         kvm->mmu_notifier_count--;
 356         spin_unlock(&kvm->mmu_lock);
 357
 358         BUG_ON(kvm->mmu_notifier_count < 0);
 359 }
 360
 361 static int kvm_mmu_notifier_clear_flush_young(struct mmu_notifier *mn,
 362                                               struct mm_struct *mm,
 363                                               unsigned long address)
 364 {
 365         struct kvm *kvm = mmu_notifier_to_kvm(mn);
 366         int young, idx;
 367
 368         idx = srcu_read_lock(&kvm->srcu);
 369         spin_lock(&kvm->mmu_lock);
 370
 371         young = kvm_age_hva(kvm, address);
 372         if (young)
 373                 kvm_flush_remote_tlbs(kvm);
 374
 375         spin_unlock(&kvm->mmu_lock);
 376         srcu_read_unlock(&kvm->srcu, idx);
 377
 378         return young;
 379 }
 380
 381 static int kvm_mmu_notifier_test_young(struct mmu_notifier *mn,
 382                                        struct mm_struct *mm,
 383                                        unsigned long address)
 384 {
 385         struct kvm *kvm = mmu_notifier_to_kvm(mn);
 386         int young, idx;
 387
 388         idx = srcu_read_lock(&kvm->srcu);
 389         spin_lock(&kvm->mmu_lock);
 390         young = kvm_test_age_hva(kvm, address);
 391         spin_unlock(&kvm->mmu_lock);
 392         srcu_read_unlock(&kvm->srcu, idx);
 393
 394         return young;
 395 }
 396
 397 static void kvm_mmu_notifier_release(struct mmu_notifier *mn,
 398                                      struct mm_struct *mm)
 399 {
 400         struct kvm *kvm = mmu_notifier_to_kvm(mn);
 401         int idx;
 402
 403         idx = srcu_read_lock(&kvm->srcu);
 404         kvm_arch_flush_shadow_all(kvm);
 405         srcu_read_unlock(&kvm->srcu, idx);
 406 }
 407
 408 static const struct mmu_notifier_ops kvm_mmu_notifier_ops = {
 409         .invalidate_page        = kvm_mmu_notifier_invalidate_page,
 410         .invalidate_range_start = kvm_mmu_notifier_invalidate_range_start,
 411         .invalidate_range_end   = kvm_mmu_notifier_invalidate_range_end,
 412         .clear_flush_young      = kvm_mmu_notifier_clear_flush_young,
 413         .test_young             = kvm_mmu_notifier_test_young,
 414         .change_pte             = kvm_mmu_notifier_change_pte,
 415         .release                = kvm_mmu_notifier_release,
 416 };
 417
 418 static int kvm_init_mmu_notifier(struct kvm *kvm)
 419 {
 420         kvm->mmu_notifier.ops = &kvm_mmu_notifier_ops;
 421         return mmu_notifier_register(&kvm->mmu_notifier, current->mm);
 422 }
 423
 424 #else  /* !(CONFIG_MMU_NOTIFIER && KVM_ARCH_WANT_MMU_NOTIFIER) */
 425
 426 static int kvm_init_mmu_notifier(struct kvm *kvm)
 427 {
 428         return 0;
 429 }
 430
 431 #endif /* CONFIG_MMU_NOTIFIER && KVM_ARCH_WANT_MMU_NOTIFIER */
 432
 433 static void kvm_init_memslots_id(struct kvm *kvm)
 434 {
 435         int i;
 436         struct kvm_memslots *slots = kvm->memslots;
 437
 438         for (i = 0; i < KVM_MEM_SLOTS_NUM; i++)
 439                 slots->id_to_index[i] = slots->memslots[i].id = i;
 440 }
 441
 442 static struct kvm *kvm_create_vm(unsigned long type)
 443 {
 444         int r, i;
 445         struct kvm *kvm = kvm_arch_alloc_vm();
 446
 447         if (!kvm)
 448                 return ERR_PTR(-ENOMEM);
 449
 450         r = kvm_arch_init_vm(kvm, type);
 451         if (r)
 452                 goto out_err_nodisable;
 453
 454         r = hardware_enable_all();
 455         if (r)
 456                 goto out_err_nodisable;
 457
 458 #ifdef CONFIG_HAVE_KVM_IRQCHIP
 459         INIT_HLIST_HEAD(&kvm->mask_notifier_list);
 460         INIT_HLIST_HEAD(&kvm->irq_ack_notifier_list);
 461 #endif
 462
 463         BUILD_BUG_ON(KVM_MEM_SLOTS_NUM > SHRT_MAX);
 464
 465         r = -ENOMEM;
 466         kvm->memslots = kzalloc(sizeof(struct kvm_memslots), GFP_KERNEL);
 467         if (!kvm->memslots)
 468                 goto out_err_nosrcu;
 469         kvm_init_memslots_id(kvm);
 470         if (init_srcu_struct(&kvm->srcu))
 471                 goto out_err_nosrcu;
 472         for (i = 0; i < KVM_NR_BUSES; i++) {
 473                 kvm->buses[i] = kzalloc(sizeof(struct kvm_io_bus),
 474                                         GFP_KERNEL);
 475                 if (!kvm->buses[i])
 476                         goto out_err;
 477         }
 478
 479         spin_lock_init(&kvm->mmu_lock);
 480         kvm->mm = current->mm;
 481         atomic_inc(&kvm->mm->mm_count);
 482         kvm_eventfd_init(kvm);
 483         mutex_init(&kvm->lock);
 484         mutex_init(&kvm->irq_lock);
 485         mutex_init(&kvm->slots_lock);
 486         atomic_set(&kvm->users_count, 1);
 487         INIT_LIST_HEAD(&kvm->devices);
 488
 489         r = kvm_init_mmu_notifier(kvm);
 490         if (r)
 491                 goto out_err;
 492
 493         raw_spin_lock(&kvm_lock);
 494         list_add(&kvm->vm_list, &vm_list);
 495         raw_spin_unlock(&kvm_lock);
 496
 497         return kvm;
 498
 499 out_err:
 500         cleanup_srcu_struct(&kvm->srcu);
 501 out_err_nosrcu:
 502         hardware_disable_all();
 503 out_err_nodisable:
 504         for (i = 0; i < KVM_NR_BUSES; i++)
 505                 kfree(kvm->buses[i]);
 506         kfree(kvm->memslots);
 507         kvm_arch_free_vm(kvm);
 508         return ERR_PTR(r);
 509 }
 510
 511 /*
 512  * Avoid using vmalloc for a small buffer.
 513  * Should not be used when the size is statically known.
 514  */
 515 void *kvm_kvzalloc(unsigned long size)
 516 {
 517         if (size > PAGE_SIZE)
 518                 return vzalloc(size);
 519         else
 520                 return kzalloc(size, GFP_KERNEL);
 521 }
 522
 523 void kvm_kvfree(const void *addr)
 524 {
 525         if (is_vmalloc_addr(addr))
 526                 vfree(addr);
 527         else
 528                 kfree(addr);
 529 }
 530
 531 static void kvm_destroy_dirty_bitmap(struct kvm_memory_slot *memslot)
 532 {
 533         if (!memslot->dirty_bitmap)
 534                 return;
 535
 536         kvm_kvfree(memslot->dirty_bitmap);
 537         memslot->dirty_bitmap = NULL;
 538 }
 539
 540 /*
 541  * Free any memory in @free but not in @dont.
 542  */
 543 static void kvm_free_physmem_slot(struct kvm_memory_slot *free,
 544                                   struct kvm_memory_slot *dont)
 545 {
 546         if (!dont || free->dirty_bitmap != dont->dirty_bitmap)
 547                 kvm_destroy_dirty_bitmap(free);
 548
 549         kvm_arch_free_memslot(free, dont);
 550
 551         free->npages = 0;
 552 }
 553
 554 void kvm_free_physmem(struct kvm *kvm)
 555 {
 556         struct kvm_memslots *slots = kvm->memslots;
 557         struct kvm_memory_slot *memslot;
 558
 559         kvm_for_each_memslot(memslot, slots)
 560                 kvm_free_physmem_slot(memslot, NULL);
 561
 562         kfree(kvm->memslots);
 563 }
 564
 565 static void kvm_destroy_devices(struct kvm *kvm)
 566 {
 567         struct list_head *node, *tmp;
 568
 569         list_for_each_safe(node, tmp, &kvm->devices) {
 570                 struct kvm_device *dev =
 571                         list_entry(node, struct kvm_device, vm_node);
 572
 573                 list_del(node);
 574                 dev->ops->destroy(dev);
 575         }
 576 }
 577
 578 static void kvm_destroy_vm(struct kvm *kvm)
 579 {
 580         int i;
 581         struct mm_struct *mm = kvm->mm;
 582
 583         kvm_arch_sync_events(kvm);
 584         raw_spin_lock(&kvm_lock);
 585         list_del(&kvm->vm_list);
 586         raw_spin_unlock(&kvm_lock);
 587         kvm_free_irq_routing(kvm);
 588         for (i = 0; i < KVM_NR_BUSES; i++)
 589                 kvm_io_bus_destroy(kvm->buses[i]);
 590         kvm_coalesced_mmio_free(kvm);
 591 #if defined(CONFIG_MMU_NOTIFIER) && defined(KVM_ARCH_WANT_MMU_NOTIFIER)
 592         mmu_notifier_unregister(&kvm->mmu_notifier, kvm->mm);
 593 #else
 594         kvm_arch_flush_shadow_all(kvm);
 595 #endif
 596         kvm_arch_destroy_vm(kvm);
 597         kvm_destroy_devices(kvm);
 598         kvm_free_physmem(kvm);
 599         cleanup_srcu_struct(&kvm->srcu);
 600         kvm_arch_free_vm(kvm);
 601         hardware_disable_all();
 602         mmdrop(mm);
 603 }
 604
 605 void kvm_get_kvm(struct kvm *kvm)
 606 {
 607         atomic_inc(&kvm->users_count);
 608 }
 609 EXPORT_SYMBOL_GPL(kvm_get_kvm);
 610
 611 void kvm_put_kvm(struct kvm *kvm)
 612 {
 613         if (atomic_dec_and_test(&kvm->users_count))
 614                 kvm_destroy_vm(kvm);
 615 }
 616 EXPORT_SYMBOL_GPL(kvm_put_kvm);
 617
 618
 619 static int kvm_vm_release(struct inode *inode, struct file *filp)
 620 {
 621         struct kvm *kvm = filp->private_data;
 622
 623         kvm_irqfd_release(kvm);
 624
 625         kvm_put_kvm(kvm);
 626         return 0;
 627 }
 628
 629 /*
 630  * Allocation size is twice as large as the actual dirty bitmap size.
 631  * See x86's kvm_vm_ioctl_get_dirty_log() why this is needed.
 632  */
 633 static int kvm_create_dirty_bitmap(struct kvm_memory_slot *memslot)
 634 {
 635 #ifndef CONFIG_S390
 636         unsigned long dirty_bytes = 2 * kvm_dirty_bitmap_bytes(memslot);
 637
 638         memslot->dirty_bitmap = kvm_kvzalloc(dirty_bytes);
 639         if (!memslot->dirty_bitmap)
 640                 return -ENOMEM;
 641
 642 #endif /* !CONFIG_S390 */
 643         return 0;
 644 }
 645
 646 static int cmp_memslot(const void *slot1, const void *slot2)
 647 {
 648         struct kvm_memory_slot *s1, *s2;
 649
 650         s1 = (struct kvm_memory_slot *)slot1;
 651         s2 = (struct kvm_memory_slot *)slot2;
 652
 653         if (s1->npages < s2->npages)
 654                 return 1;
 655         if (s1->npages > s2->npages)
 656                 return -1;
 657
 658         return 0;
 659 }
 660
 661 /*
 662  * Sort the memslots base on its size, so the larger slots
 663  * will get better fit.
 664  */
 665 static void sort_memslots(struct kvm_memslots *slots)
 666 {
 667         int i;
 668
 669         sort(slots->memslots, KVM_MEM_SLOTS_NUM,
 670               sizeof(struct kvm_memory_slot), cmp_memslot, NULL);
 671
 672         for (i = 0; i < KVM_MEM_SLOTS_NUM; i++)
 673                 slots->id_to_index[slots->memslots[i].id] = i;
 674 }
 675
 676 void update_memslots(struct kvm_memslots *slots, struct kvm_memory_slot *new,
 677                      u64 last_generation)
 678 {
 679         if (new) {
 680                 int id = new->id;
 681                 struct kvm_memory_slot *old = id_to_memslot(slots, id);
 682                 unsigned long npages = old->npages;
 683
 684                 *old = *new;
 685                 if (new->npages != npages)
 686                         sort_memslots(slots);
 687         }
 688
 689         slots->generation = last_generation + 1;
 690 }
 691
 692 static int check_memory_region_flags(struct kvm_userspace_memory_region *mem)
 693 {
 694         u32 valid_flags = KVM_MEM_LOG_DIRTY_PAGES;
 695
 696 #ifdef KVM_CAP_READONLY_MEM
 697         valid_flags |= KVM_MEM_READONLY;
 698 #endif
 699
 700         if (mem->flags & ~valid_flags)
 701                 return -EINVAL;
 702
 703         return 0;
 704 }
 705
 706 static struct kvm_memslots *install_new_memslots(struct kvm *kvm,
 707                 struct kvm_memslots *slots, struct kvm_memory_slot *new)
 708 {
 709         struct kvm_memslots *old_memslots = kvm->memslots;
 710
 711         update_memslots(slots, new, kvm->memslots->generation);
 712         rcu_assign_pointer(kvm->memslots, slots);
 713         synchronize_srcu_expedited(&kvm->srcu);
 714
 715         kvm_arch_memslots_updated(kvm);
 716
 717         return old_memslots;
 718 }
 719
 720 /*
 721  * Allocate some memory and give it an address in the guest physical address
 722  * space.
 723  *
 724  * Discontiguous memory is allowed, mostly for framebuffers.
 725  *
 726  * Must be called holding mmap_sem for write.
 727  */
 728 int __kvm_set_memory_region(struct kvm *kvm,
 729                             struct kvm_userspace_memory_region *mem)
 730 {
 731         int r;
 732         gfn_t base_gfn;
 733         unsigned long npages;
 734         struct kvm_memory_slot *slot;
 735         struct kvm_memory_slot old, new;
 736         struct kvm_memslots *slots = NULL, *old_memslots;
 737         enum kvm_mr_change change;
 738
 739         r = check_memory_region_flags(mem);
 740         if (r)
 741                 goto out;
 742
 743         r = -EINVAL;
 744         /* General sanity checks */
 745         if (mem->memory_size & (PAGE_SIZE - 1))
 746                 goto out;
 747         if (mem->guest_phys_addr & (PAGE_SIZE - 1))
 748                 goto out;
 749         /* We can read the guest memory with __xxx_user() later on. */
 750         if ((mem->slot < KVM_USER_MEM_SLOTS) &&
 751             ((mem->userspace_addr & (PAGE_SIZE - 1)) ||
 752              !access_ok(VERIFY_WRITE,
 753                         (void __user *)(unsigned long)mem->userspace_addr,
 754                         mem->memory_size)))
 755                 goto out;
 756         if (mem->slot >= KVM_MEM_SLOTS_NUM)
 757                 goto out;
 758         if (mem->guest_phys_addr + mem->memory_size < mem->guest_phys_addr)
 759                 goto out;
 760
 761         slot = id_to_memslot(kvm->memslots, mem->slot);
 762         base_gfn = mem->guest_phys_addr >> PAGE_SHIFT;
 763         npages = mem->memory_size >> PAGE_SHIFT;
 764
 765         r = -EINVAL;
 766         if (npages > KVM_MEM_MAX_NR_PAGES)
 767                 goto out;
 768
 769         if (!npages)
 770                 mem->flags &= ~KVM_MEM_LOG_DIRTY_PAGES;
 771
 772         new = old = *slot;
 773
 774         new.id = mem->slot;
 775         new.base_gfn = base_gfn;
 776         new.npages = npages;
 777         new.flags = mem->flags;
 778
 779         r = -EINVAL;
 780         if (npages) {
 781                 if (!old.npages)
 782                         change = KVM_MR_CREATE;
 783                 else { /* Modify an existing slot. */
 784                         if ((mem->userspace_addr != old.userspace_addr) ||
 785                             (npages != old.npages) ||
 786                             ((new.flags ^ old.flags) & KVM_MEM_READONLY))
 787                                 goto out;
 788
 789                         if (base_gfn != old.base_gfn)
 790                                 change = KVM_MR_MOVE;
 791                         else if (new.flags != old.flags)
 792                                 change = KVM_MR_FLAGS_ONLY;
 793                         else { /* Nothing to change. */
 794                                 r = 0;
 795                                 goto out;
 796                         }
 797                 }
 798         } else if (old.npages) {
 799                 change = KVM_MR_DELETE;
 800         } else /* Modify a non-existent slot: disallowed. */
 801                 goto out;
 802
 803         if ((change == KVM_MR_CREATE) || (change == KVM_MR_MOVE)) {
 804                 /* Check for overlaps */
 805                 r = -EEXIST;
 806                 kvm_for_each_memslot(slot, kvm->memslots) {
 807                         if ((slot->id >= KVM_USER_MEM_SLOTS) ||
 808                             (slot->id == mem->slot))
 809                                 continue;
 810                         if (!((base_gfn + npages <= slot->base_gfn) ||
 811                               (base_gfn >= slot->base_gfn + slot->npages)))
 812                                 goto out;
 813                 }
 814         }
 815
 816         /* Free page dirty bitmap if unneeded */
 817         if (!(new.flags & KVM_MEM_LOG_DIRTY_PAGES))
 818                 new.dirty_bitmap = NULL;
 819
 820         r = -ENOMEM;
 821         if (change == KVM_MR_CREATE) {
 822                 new.userspace_addr = mem->userspace_addr;
 823
 824                 if (kvm_arch_create_memslot(&new, npages))
 825                         goto out_free;
 826         }
 827
 828         /* Allocate page dirty bitmap if needed */
 829         if ((new.flags & KVM_MEM_LOG_DIRTY_PAGES) && !new.dirty_bitmap) {
 830                 if (kvm_create_dirty_bitmap(&new) < 0)
 831                         goto out_free;
 832         }
 833
 834         if ((change == KVM_MR_DELETE) || (change == KVM_MR_MOVE)) {
 835                 r = -ENOMEM;
 836                 slots = kmemdup(kvm->memslots, sizeof(struct kvm_memslots),
 837                                 GFP_KERNEL);
 838                 if (!slots)
 839                         goto out_free;
 840                 slot = id_to_memslot(slots, mem->slot);
 841                 slot->flags |= KVM_MEMSLOT_INVALID;
 842
 843                 old_memslots = install_new_memslots(kvm, slots, NULL);
 844
 845                 /* slot was deleted or moved, clear iommu mapping */
 846                 kvm_iommu_unmap_pages(kvm, &old);
 847                 /* From this point no new shadow pages pointing to a deleted,
 848                  * or moved, memslot will be created.
 849                  *
 850                  * validation of sp->gfn happens in:
 851                  *      - gfn_to_hva (kvm_read_guest, gfn_to_pfn)
 852                  *      - kvm_is_visible_gfn (mmu_check_roots)
 853                  */
 854                 kvm_arch_flush_shadow_memslot(kvm, slot);
 855                 slots = old_memslots;
 856         }
 857
 858         r = kvm_arch_prepare_memory_region(kvm, &new, mem, change);
 859         if (r)
 860                 goto out_slots;
 861
 862         r = -ENOMEM;
 863         /*
 864          * We can re-use the old_memslots from above, the only difference
 865          * from the currently installed memslots is the invalid flag.  This
 866          * will get overwritten by update_memslots anyway.
 867          */
 868         if (!slots) {
 869                 slots = kmemdup(kvm->memslots, sizeof(struct kvm_memslots),
 870                                 GFP_KERNEL);
 871                 if (!slots)
 872                         goto out_free;
 873         }
 874
 875         /*
 876          * IOMMU mapping:  New slots need to be mapped.  Old slots need to be
 877          * un-mapped and re-mapped if their base changes.  Since base change
 878          * unmapping is handled above with slot deletion, mapping alone is
 879          * needed here.  Anything else the iommu might care about for existing
 880          * slots (size changes, userspace addr changes and read-only flag
 881          * changes) is disallowed above, so any other attribute changes getting
 882          * here can be skipped.
 883          */
 884         if ((change == KVM_MR_CREATE) || (change == KVM_MR_MOVE)) {
 885                 r = kvm_iommu_map_pages(kvm, &new);
 886                 if (r)
 887                         goto out_slots;
 888         }
 889
 890         /* actual memory is freed via old in kvm_free_physmem_slot below */
 891         if (change == KVM_MR_DELETE) {
 892                 new.dirty_bitmap = NULL;
 893                 memset(&new.arch, 0, sizeof(new.arch));
 894         }
 895
 896         old_memslots = install_new_memslots(kvm, slots, &new);
 897
 898         kvm_arch_commit_memory_region(kvm, mem, &old, change);
 899
 900         kvm_free_physmem_slot(&old, &new);
 901         kfree(old_memslots);
 902
 903         return 0;
 904
 905 out_slots:
 906         kfree(slots);
 907 out_free:
 908         kvm_free_physmem_slot(&new, &old);
 909 out:
 910         return r;
 911 }
 912 EXPORT_SYMBOL_GPL(__kvm_set_memory_region);
 913
 914 int kvm_set_memory_region(struct kvm *kvm,
 915                           struct kvm_userspace_memory_region *mem)
 916 {
 917         int r;
 918
 919         mutex_lock(&kvm->slots_lock);
 920         r = __kvm_set_memory_region(kvm, mem);
 921         mutex_unlock(&kvm->slots_lock);
 922         return r;
 923 }
 924 EXPORT_SYMBOL_GPL(kvm_set_memory_region);
 925
 926 int kvm_vm_ioctl_set_memory_region(struct kvm *kvm,
 927                                    struct kvm_userspace_memory_region *mem)
 928 {
 929         if (mem->slot >= KVM_USER_MEM_SLOTS)
 930                 return -EINVAL;
 931         return kvm_set_memory_region(kvm, mem);
 932 }
 933
 934 int kvm_get_dirty_log(struct kvm *kvm,
 935                         struct kvm_dirty_log *log, int *is_dirty)
 936 {
 937         struct kvm_memory_slot *memslot;
 938         int r, i;
 939         unsigned long n;
 940         unsigned long any = 0;
 941
 942         r = -EINVAL;
 943         if (log->slot >= KVM_USER_MEM_SLOTS)
 944                 goto out;
 945
 946         memslot = id_to_memslot(kvm->memslots, log->slot);
 947         r = -ENOENT;
 948         if (!memslot->dirty_bitmap)
 949                 goto out;
 950
 951         n = kvm_dirty_bitmap_bytes(memslot);
 952
 953         for (i = 0; !any && i < n/sizeof(long); ++i)
 954                 any = memslot->dirty_bitmap[i];
 955
 956         r = -EFAULT;
 957         if (copy_to_user(log->dirty_bitmap, memslot->dirty_bitmap, n))
 958                 goto out;
 959
 960         if (any)
 961                 *is_dirty = 1;
 962
 963         r = 0;
 964 out:
 965         return r;
 966 }
 967
 968 bool kvm_largepages_enabled(void)
 969 {
 970         return largepages_enabled;
 971 }
 972
 973 void kvm_disable_largepages(void)
 974 {
 975         largepages_enabled = false;
 976 }
 977 EXPORT_SYMBOL_GPL(kvm_disable_largepages);
 978
 979 struct kvm_memory_slot *gfn_to_memslot(struct kvm *kvm, gfn_t gfn)
 980 {
 981         return __gfn_to_memslot(kvm_memslots(kvm), gfn);
 982 }
 983 EXPORT_SYMBOL_GPL(gfn_to_memslot);
 984
 985 int kvm_is_visible_gfn(struct kvm *kvm, gfn_t gfn)
 986 {
 987         struct kvm_memory_slot *memslot = gfn_to_memslot(kvm, gfn);
 988
 989         if (!memslot || memslot->id >= KVM_USER_MEM_SLOTS ||
 990               memslot->flags & KVM_MEMSLOT_INVALID)
 991                 return 0;
 992
 993         return 1;
 994 }
 995 EXPORT_SYMBOL_GPL(kvm_is_visible_gfn);
 996
 997 unsigned long kvm_host_page_size(struct kvm *kvm, gfn_t gfn)
 998 {
 999         struct vm_area_struct *vma;
1000         unsigned long addr, size;
1001
1002         size = PAGE_SIZE;
1003
1004         addr = gfn_to_hva(kvm, gfn);
1005         if (kvm_is_error_hva(addr))
1006                 return PAGE_SIZE;
1007
1008         down_read(&current->mm->mmap_sem);
1009         vma = find_vma(current->mm, addr);
1010         if (!vma)
1011                 goto out;
1012
1013         size = vma_kernel_pagesize(vma);
1014
1015 out:
1016         up_read(&current->mm->mmap_sem);
1017
1018         return size;
1019 }
1020
1021 static bool memslot_is_readonly(struct kvm_memory_slot *slot)
1022 {
1023         return slot->flags & KVM_MEM_READONLY;
1024 }
1025
1026 static unsigned long __gfn_to_hva_many(struct kvm_memory_slot *slot, gfn_t gfn,
1027                                        gfn_t *nr_pages, bool write)
1028 {
1029         if (!slot || slot->flags & KVM_MEMSLOT_INVALID)
1030                 return KVM_HVA_ERR_BAD;
1031
1032         if (memslot_is_readonly(slot) && write)
1033                 return KVM_HVA_ERR_RO_BAD;
1034
1035         if (nr_pages)
1036                 *nr_pages = slot->npages - (gfn - slot->base_gfn);
1037
1038         return __gfn_to_hva_memslot(slot, gfn);
1039 }
1040
1041 static unsigned long gfn_to_hva_many(struct kvm_memory_slot *slot, gfn_t gfn,
1042                                      gfn_t *nr_pages)
1043 {
1044         return __gfn_to_hva_many(slot, gfn, nr_pages, true);
1045 }
1046
1047 unsigned long gfn_to_hva_memslot(struct kvm_memory_slot *slot,
1048                                  gfn_t gfn)
1049 {
1050         return gfn_to_hva_many(slot, gfn, NULL);
1051 }
1052 EXPORT_SYMBOL_GPL(gfn_to_hva_memslot);
1053
1054 unsigned long gfn_to_hva(struct kvm *kvm, gfn_t gfn)
1055 {
1056         return gfn_to_hva_many(gfn_to_memslot(kvm, gfn), gfn, NULL);
1057 }
1058 EXPORT_SYMBOL_GPL(gfn_to_hva);
1059
1060 /*
1061  * If writable is set to false, the hva returned by this function is only
1062  * allowed to be read.
1063  */
1064 unsigned long gfn_to_hva_prot(struct kvm *kvm, gfn_t gfn, bool *writable)
1065 {
1066         struct kvm_memory_slot *slot = gfn_to_memslot(kvm, gfn);
1067         unsigned long hva = __gfn_to_hva_many(slot, gfn, NULL, false);
1068
1069         if (!kvm_is_error_hva(hva) && writable)
1070                 *writable = !memslot_is_readonly(slot);
1071
1072         return hva;
1073 }
1074
1075 static int kvm_read_hva(void *data, void __user *hva, int len)
1076 {
1077         return __copy_from_user(data, hva, len);
1078 }
1079
1080 static int kvm_read_hva_atomic(void *data, void __user *hva, int len)
1081 {
1082         return __copy_from_user_inatomic(data, hva, len);
1083 }
1084
1085 static int get_user_page_nowait(struct task_struct *tsk, struct mm_struct *mm,
1086         unsigned long start, int write, struct page **page)
1087 {
1088         int flags = FOLL_TOUCH | FOLL_NOWAIT | FOLL_HWPOISON | FOLL_GET;
1089
1090         if (write)
1091                 flags |= FOLL_WRITE;
1092
1093         return __get_user_pages(tsk, mm, start, 1, flags, page, NULL, NULL);
1094 }
1095
1096 static inline int check_user_page_hwpoison(unsigned long addr)
1097 {
1098         int rc, flags = FOLL_TOUCH | FOLL_HWPOISON | FOLL_WRITE;
1099
1100         rc = __get_user_pages(current, current->mm, addr, 1,
1101                               flags, NULL, NULL, NULL);
1102         return rc == -EHWPOISON;
1103 }
1104
1105 /*
1106  * The atomic path to get the writable pfn which will be stored in @pfn,
1107  * true indicates success, otherwise false is returned.
1108  */
1109 static bool hva_to_pfn_fast(unsigned long addr, bool atomic, bool *async,
1110                             bool write_fault, bool *writable, pfn_t *pfn)
1111 {
1112         struct page *page[1];
1113         int npages;
1114
1115         if (!(async || atomic))
1116                 return false;
1117
1118         /*
1119          * Fast pin a writable pfn only if it is a write fault request
1120          * or the caller allows to map a writable pfn for a read fault
1121          * request.
1122          */
1123         if (!(write_fault || writable))
1124                 return false;
1125
1126         npages = __get_user_pages_fast(addr, 1, 1, page);
1127         if (npages == 1) {
1128                 *pfn = page_to_pfn(page[0]);
1129
1130                 if (writable)
1131                         *writable = true;
1132                 return true;
1133         }
1134
1135         return false;
1136 }
1137
1138 /*
1139  * The slow path to get the pfn of the specified host virtual address,
1140  * 1 indicates success, -errno is returned if error is detected.
1141  */
1142 static int hva_to_pfn_slow(unsigned long addr, bool *async, bool write_fault,
1143                            bool *writable, pfn_t *pfn)
1144 {
1145         struct page *page[1];
1146         int npages = 0;
1147
1148         might_sleep();
1149
1150         if (writable)
1151                 *writable = write_fault;
1152
1153         if (async) {
1154                 down_read(&current->mm->mmap_sem);
1155                 npages = get_user_page_nowait(current, current->mm,
1156                                               addr, write_fault, page);
1157                 up_read(&current->mm->mmap_sem);
1158         } else
1159                 npages = get_user_pages_fast(addr, 1, write_fault,
1160                                              page);
1161         if (npages != 1)
1162                 return npages;
1163
1164         /* map read fault as writable if possible */
1165         if (unlikely(!write_fault) && writable) {
1166                 struct page *wpage[1];
1167
1168                 npages = __get_user_pages_fast(addr, 1, 1, wpage);
1169                 if (npages == 1) {
1170                         *writable = true;
1171                         put_page(page[0]);
1172                         page[0] = wpage[0];
1173                 }
1174
1175                 npages = 1;
1176         }
1177         *pfn = page_to_pfn(page[0]);
1178         return npages;
1179 }
1180
1181 static bool vma_is_valid(struct vm_area_struct *vma, bool write_fault)
1182 {
1183         if (unlikely(!(vma->vm_flags & VM_READ)))
1184                 return false;
1185
1186         if (write_fault && (unlikely(!(vma->vm_flags & VM_WRITE))))
1187                 return false;
1188
1189         return true;
1190 }
1191
1192 /*
1193  * Pin guest page in memory and return its pfn.
1194  * @addr: host virtual address which maps memory to the guest
1195  * @atomic: whether this function can sleep
1196  * @async: whether this function need to wait IO complete if the
1197  *         host page is not in the memory
1198  * @write_fault: whether we should get a writable host page
1199  * @writable: whether it allows to map a writable host page for !@write_fault
1200  *
1201  * The function will map a writable host page for these two cases:
1202  * 1): @write_fault = true
1203  * 2): @write_fault = false && @writable, @writable will tell the caller
1204  *     whether the mapping is writable.
1205  */
1206 static pfn_t hva_to_pfn(unsigned long addr, bool atomic, bool *async,
1207                         bool write_fault, bool *writable)
1208 {
1209         struct vm_area_struct *vma;
1210         pfn_t pfn = 0;
1211         int npages;
1212
1213         /* we can do it either atomically or asynchronously, not both */
1214         BUG_ON(atomic && async);
1215
1216         if (hva_to_pfn_fast(addr, atomic, async, write_fault, writable, &pfn))
1217                 return pfn;
1218
1219         if (atomic)
1220                 return KVM_PFN_ERR_FAULT;
1221
1222         npages = hva_to_pfn_slow(addr, async, write_fault, writable, &pfn);
1223         if (npages == 1)
1224                 return pfn;
1225
1226         down_read(&current->mm->mmap_sem);
1227         if (npages == -EHWPOISON ||
1228               (!async && check_user_page_hwpoison(addr))) {
1229                 pfn = KVM_PFN_ERR_HWPOISON;
1230                 goto exit;
1231         }
1232
1233         vma = find_vma_intersection(current->mm, addr, addr + 1);
1234
1235         if (vma == NULL)
1236                 pfn = KVM_PFN_ERR_FAULT;
1237         else if ((vma->vm_flags & VM_PFNMAP)) {
1238                 pfn = ((addr - vma->vm_start) >> PAGE_SHIFT) +
1239                         vma->vm_pgoff;
1240                 BUG_ON(!kvm_is_mmio_pfn(pfn));
1241         } else {
1242                 if (async && vma_is_valid(vma, write_fault))
1243                         *async = true;
1244                 pfn = KVM_PFN_ERR_FAULT;
1245         }
1246 exit:
1247         up_read(&current->mm->mmap_sem);
1248         return pfn;
1249 }
1250
1251 static pfn_t
1252 __gfn_to_pfn_memslot(struct kvm_memory_slot *slot, gfn_t gfn, bool atomic,
1253                      bool *async, bool write_fault, bool *writable)
1254 {
1255         unsigned long addr = __gfn_to_hva_many(slot, gfn, NULL, write_fault);
1256
1257         if (addr == KVM_HVA_ERR_RO_BAD)
1258                 return KVM_PFN_ERR_RO_FAULT;
1259
1260         if (kvm_is_error_hva(addr))
1261                 return KVM_PFN_NOSLOT;
1262
1263         /* Do not map writable pfn in the readonly memslot. */
1264         if (writable && memslot_is_readonly(slot)) {
1265                 *writable = false;
1266                 writable = NULL;
1267         }
1268
1269         return hva_to_pfn(addr, atomic, async, write_fault,
1270                           writable);
1271 }
1272
1273 static pfn_t __gfn_to_pfn(struct kvm *kvm, gfn_t gfn, bool atomic, bool *async,
1274                           bool write_fault, bool *writable)
1275 {
1276         struct kvm_memory_slot *slot;
1277
1278         if (async)
1279                 *async = false;
1280
1281         slot = gfn_to_memslot(kvm, gfn);
1282
1283         return __gfn_to_pfn_memslot(slot, gfn, atomic, async, write_fault,
1284                                     writable);
1285 }
1286
1287 pfn_t gfn_to_pfn_atomic(struct kvm *kvm, gfn_t gfn)
1288 {
1289         return __gfn_to_pfn(kvm, gfn, true, NULL, true, NULL);
1290 }
1291 EXPORT_SYMBOL_GPL(gfn_to_pfn_atomic);
1292
1293 pfn_t gfn_to_pfn_async(struct kvm *kvm, gfn_t gfn, bool *async,
1294                        bool write_fault, bool *writable)
1295 {
1296         return __gfn_to_pfn(kvm, gfn, false, async, write_fault, writable);
1297 }
1298 EXPORT_SYMBOL_GPL(gfn_to_pfn_async);
1299
1300 pfn_t gfn_to_pfn(struct kvm *kvm, gfn_t gfn)
1301 {
1302         return __gfn_to_pfn(kvm, gfn, false, NULL, true, NULL);
1303 }
1304 EXPORT_SYMBOL_GPL(gfn_to_pfn);
1305
1306 pfn_t gfn_to_pfn_prot(struct kvm *kvm, gfn_t gfn, bool write_fault,
1307                       bool *writable)
1308 {
1309         return __gfn_to_pfn(kvm, gfn, false, NULL, write_fault, writable);
1310 }
1311 EXPORT_SYMBOL_GPL(gfn_to_pfn_prot);
1312
1313 pfn_t gfn_to_pfn_memslot(struct kvm_memory_slot *slot, gfn_t gfn)
1314 {
1315         return __gfn_to_pfn_memslot(slot, gfn, false, NULL, true, NULL);
1316 }
1317
1318 pfn_t gfn_to_pfn_memslot_atomic(struct kvm_memory_slot *slot, gfn_t gfn)
1319 {
1320         return __gfn_to_pfn_memslot(slot, gfn, true, NULL, true, NULL);
1321 }
1322 EXPORT_SYMBOL_GPL(gfn_to_pfn_memslot_atomic);
1323
1324 int gfn_to_page_many_atomic(struct kvm *kvm, gfn_t gfn, struct page **pages,
1325                                                                   int nr_pages)
1326 {
1327         unsigned long addr;
1328         gfn_t entry;
1329
1330         addr = gfn_to_hva_many(gfn_to_memslot(kvm, gfn), gfn, &entry);
1331         if (kvm_is_error_hva(addr))
1332                 return -1;
1333
1334         if (entry < nr_pages)
1335                 return 0;
1336
1337         return __get_user_pages_fast(addr, nr_pages, 1, pages);
1338 }
1339 EXPORT_SYMBOL_GPL(gfn_to_page_many_atomic);
1340
1341 static struct page *kvm_pfn_to_page(pfn_t pfn)
1342 {
1343         if (is_error_noslot_pfn(pfn))
1344                 return KVM_ERR_PTR_BAD_PAGE;
1345
1346         if (kvm_is_mmio_pfn(pfn)) {
1347                 WARN_ON(1);
1348                 return KVM_ERR_PTR_BAD_PAGE;
1349         }
1350
1351         return pfn_to_page(pfn);
1352 }
1353
1354 struct page *gfn_to_page(struct kvm *kvm, gfn_t gfn)
1355 {
1356         pfn_t pfn;
1357
1358         pfn = gfn_to_pfn(kvm, gfn);
1359
1360         return kvm_pfn_to_page(pfn);
1361 }
1362
1363 EXPORT_SYMBOL_GPL(gfn_to_page);
1364
1365 void kvm_release_page_clean(struct page *page)
1366 {
1367         WARN_ON(is_error_page(page));
1368
1369         kvm_release_pfn_clean(page_to_pfn(page));
1370 }
1371 EXPORT_SYMBOL_GPL(kvm_release_page_clean);
1372
1373 void kvm_release_pfn_clean(pfn_t pfn)
1374 {
1375         if (!is_error_noslot_pfn(pfn) && !kvm_is_mmio_pfn(pfn))
1376                 put_page(pfn_to_page(pfn));
1377 }
1378 EXPORT_SYMBOL_GPL(kvm_release_pfn_clean);
1379
1380 void kvm_release_page_dirty(struct page *page)
1381 {
1382         WARN_ON(is_error_page(page));
1383
1384         kvm_release_pfn_dirty(page_to_pfn(page));
1385 }
1386 EXPORT_SYMBOL_GPL(kvm_release_page_dirty);
1387
1388 void kvm_release_pfn_dirty(pfn_t pfn)
1389 {
1390         kvm_set_pfn_dirty(pfn);
1391         kvm_release_pfn_clean(pfn);
1392 }
1393 EXPORT_SYMBOL_GPL(kvm_release_pfn_dirty);
1394
1395 void kvm_set_page_dirty(struct page *page)
1396 {
1397         kvm_set_pfn_dirty(page_to_pfn(page));
1398 }
1399 EXPORT_SYMBOL_GPL(kvm_set_page_dirty);
1400
1401 void kvm_set_pfn_dirty(pfn_t pfn)
1402 {
1403         if (!kvm_is_mmio_pfn(pfn)) {
1404                 struct page *page = pfn_to_page(pfn);
1405                 if (!PageReserved(page))
1406                         SetPageDirty(page);
1407         }
1408 }
1409 EXPORT_SYMBOL_GPL(kvm_set_pfn_dirty);
1410
1411 void kvm_set_pfn_accessed(pfn_t pfn)
1412 {
1413         if (!kvm_is_mmio_pfn(pfn))
1414                 mark_page_accessed(pfn_to_page(pfn));
1415 }
1416 EXPORT_SYMBOL_GPL(kvm_set_pfn_accessed);
1417
1418 void kvm_get_pfn(pfn_t pfn)
1419 {
1420         if (!kvm_is_mmio_pfn(pfn))
1421                 get_page(pfn_to_page(pfn));
1422 }
1423 EXPORT_SYMBOL_GPL(kvm_get_pfn);
1424
1425 static int next_segment(unsigned long len, int offset)
1426 {
1427         if (len > PAGE_SIZE - offset)
1428                 return PAGE_SIZE - offset;
1429         else
1430                 return len;
1431 }
1432
1433 int kvm_read_guest_page(struct kvm *kvm, gfn_t gfn, void *data, int offset,
1434                         int len)
1435 {
1436         int r;
1437         unsigned long addr;
1438
1439         addr = gfn_to_hva_prot(kvm, gfn, NULL);
1440         if (kvm_is_error_hva(addr))
1441                 return -EFAULT;
1442         r = kvm_read_hva(data, (void __user *)addr + offset, len);
1443         if (r)
1444                 return -EFAULT;
1445         return 0;
1446 }
1447 EXPORT_SYMBOL_GPL(kvm_read_guest_page);
1448
1449 int kvm_read_guest(struct kvm *kvm, gpa_t gpa, void *data, unsigned long len)
1450 {
1451         gfn_t gfn = gpa >> PAGE_SHIFT;
1452         int seg;
1453         int offset = offset_in_page(gpa);
1454         int ret;
1455
1456         while ((seg = next_segment(len, offset)) != 0) {
1457                 ret = kvm_read_guest_page(kvm, gfn, data, offset, seg);
1458                 if (ret < 0)
1459                         return ret;
1460                 offset = 0;
1461                 len -= seg;
1462                 data += seg;
1463                 ++gfn;
1464         }
1465         return 0;
1466 }
1467 EXPORT_SYMBOL_GPL(kvm_read_guest);
1468
1469 int kvm_read_guest_atomic(struct kvm *kvm, gpa_t gpa, void *data,
1470                           unsigned long len)
1471 {
1472         int r;
1473         unsigned long addr;
1474         gfn_t gfn = gpa >> PAGE_SHIFT;
1475         int offset = offset_in_page(gpa);
1476
1477         addr = gfn_to_hva_prot(kvm, gfn, NULL);
1478         if (kvm_is_error_hva(addr))
1479                 return -EFAULT;
1480         pagefault_disable();
1481         r = kvm_read_hva_atomic(data, (void __user *)addr + offset, len);
1482         pagefault_enable();
1483         if (r)
1484                 return -EFAULT;
1485         return 0;
1486 }
1487 EXPORT_SYMBOL(kvm_read_guest_atomic);
1488
1489 int kvm_write_guest_page(struct kvm *kvm, gfn_t gfn, const void *data,
1490                          int offset, int len)
1491 {
1492         int r;
1493         unsigned long addr;
1494
1495         addr = gfn_to_hva(kvm, gfn);
1496         if (kvm_is_error_hva(addr))
1497                 return -EFAULT;
1498         r = __copy_to_user((void __user *)addr + offset, data, len);
1499         if (r)
1500                 return -EFAULT;
1501         mark_page_dirty(kvm, gfn);
1502         return 0;
1503 }
1504 EXPORT_SYMBOL_GPL(kvm_write_guest_page);
1505
1506 int kvm_write_guest(struct kvm *kvm, gpa_t gpa, const void *data,
1507                     unsigned long len)
1508 {
1509         gfn_t gfn = gpa >> PAGE_SHIFT;
1510         int seg;
1511         int offset = offset_in_page(gpa);
1512         int ret;
1513
1514         while ((seg = next_segment(len, offset)) != 0) {
1515                 ret = kvm_write_guest_page(kvm, gfn, data, offset, seg);
1516                 if (ret < 0)
1517                         return ret;
1518                 offset = 0;
1519                 len -= seg;
1520                 data += seg;
1521                 ++gfn;
1522         }
1523         return 0;
1524 }
1525
1526 int kvm_gfn_to_hva_cache_init(struct kvm *kvm, struct gfn_to_hva_cache *ghc,
1527                               gpa_t gpa, unsigned long len)
1528 {
1529         struct kvm_memslots *slots = kvm_memslots(kvm);
1530         int offset = offset_in_page(gpa);
1531         gfn_t start_gfn = gpa >> PAGE_SHIFT;
1532         gfn_t end_gfn = (gpa + len - 1) >> PAGE_SHIFT;
1533         gfn_t nr_pages_needed = end_gfn - start_gfn + 1;
1534         gfn_t nr_pages_avail;
1535
1536         ghc->gpa = gpa;
1537         ghc->generation = slots->generation;
1538         ghc->len = len;
1539         ghc->memslot = gfn_to_memslot(kvm, start_gfn);
1540         ghc->hva = gfn_to_hva_many(ghc->memslot, start_gfn, &nr_pages_avail);
1541         if (!kvm_is_error_hva(ghc->hva) && nr_pages_avail >= nr_pages_needed) {
1542                 ghc->hva += offset;
1543         } else {
1544                 /*
1545                  * If the requested region crosses two memslots, we still
1546                  * verify that the entire region is valid here.
1547                  */
1548                 while (start_gfn <= end_gfn) {
1549                         ghc->memslot = gfn_to_memslot(kvm, start_gfn);
1550                         ghc->hva = gfn_to_hva_many(ghc->memslot, start_gfn,
1551                                                    &nr_pages_avail);
1552                         if (kvm_is_error_hva(ghc->hva))
1553                                 return -EFAULT;
1554                         start_gfn += nr_pages_avail;
1555                 }
1556                 /* Use the slow path for cross page reads and writes. */
1557                 ghc->memslot = NULL;
1558         }
1559         return 0;
1560 }
1561 EXPORT_SYMBOL_GPL(kvm_gfn_to_hva_cache_init);
1562
1563 int kvm_write_guest_cached(struct kvm *kvm, struct gfn_to_hva_cache *ghc,
1564                            void *data, unsigned long len)
1565 {
1566         struct kvm_memslots *slots = kvm_memslots(kvm);
1567         int r;
1568
1569         BUG_ON(len > ghc->len);
1570
1571         if (slots->generation != ghc->generation)
1572                 kvm_gfn_to_hva_cache_init(kvm, ghc, ghc->gpa, ghc->len);
1573
1574         if (unlikely(!ghc->memslot))
1575                 return kvm_write_guest(kvm, ghc->gpa, data, len);
1576
1577         if (kvm_is_error_hva(ghc->hva))
1578                 return -EFAULT;
1579
1580         r = __copy_to_user((void __user *)ghc->hva, data, len);
1581         if (r)
1582                 return -EFAULT;
1583         mark_page_dirty_in_slot(kvm, ghc->memslot, ghc->gpa >> PAGE_SHIFT);
1584
1585         return 0;
1586 }
1587 EXPORT_SYMBOL_GPL(kvm_write_guest_cached);
1588
1589 int kvm_read_guest_cached(struct kvm *kvm, struct gfn_to_hva_cache *ghc,
1590                            void *data, unsigned long len)
1591 {
1592         struct kvm_memslots *slots = kvm_memslots(kvm);
1593         int r;
1594
1595         BUG_ON(len > ghc->len);
1596
1597         if (slots->generation != ghc->generation)
1598                 kvm_gfn_to_hva_cache_init(kvm, ghc, ghc->gpa, ghc->len);
1599
1600         if (unlikely(!ghc->memslot))
1601                 return kvm_read_guest(kvm, ghc->gpa, data, len);
1602
1603         if (kvm_is_error_hva(ghc->hva))
1604                 return -EFAULT;
1605
1606         r = __copy_from_user(data, (void __user *)ghc->hva, len);
1607         if (r)
1608                 return -EFAULT;
1609
1610         return 0;
1611 }
1612 EXPORT_SYMBOL_GPL(kvm_read_guest_cached);
1613
1614 int kvm_clear_guest_page(struct kvm *kvm, gfn_t gfn, int offset, int len)
1615 {
1616         return kvm_write_guest_page(kvm, gfn, (const void *) empty_zero_page,
1617                                     offset, len);
1618 }
1619 EXPORT_SYMBOL_GPL(kvm_clear_guest_page);
1620
1621 int kvm_clear_guest(struct kvm *kvm, gpa_t gpa, unsigned long len)
1622 {
1623         gfn_t gfn = gpa >> PAGE_SHIFT;
1624         int seg;
1625         int offset = offset_in_page(gpa);
1626         int ret;
1627
1628         while ((seg = next_segment(len, offset)) != 0) {
1629                 ret = kvm_clear_guest_page(kvm, gfn, offset, seg);
1630                 if (ret < 0)
1631                         return ret;
1632                 offset = 0;
1633                 len -= seg;
1634                 ++gfn;
1635         }
1636         return 0;
1637 }
1638 EXPORT_SYMBOL_GPL(kvm_clear_guest);
1639
1640 void mark_page_dirty_in_slot(struct kvm *kvm, struct kvm_memory_slot *memslot,
1641                              gfn_t gfn)
1642 {
1643         if (memslot && memslot->dirty_bitmap) {
1644                 unsigned long rel_gfn = gfn - memslot->base_gfn;
1645
1646                 set_bit_le(rel_gfn, memslot->dirty_bitmap);
1647         }
1648 }
1649
1650 void mark_page_dirty(struct kvm *kvm, gfn_t gfn)
1651 {
1652         struct kvm_memory_slot *memslot;
1653
1654         memslot = gfn_to_memslot(kvm, gfn);
1655         mark_page_dirty_in_slot(kvm, memslot, gfn);
1656 }
1657
1658 /*
1659  * The vCPU has executed a HLT instruction with in-kernel mode enabled.
1660  */
1661 void kvm_vcpu_block(struct kvm_vcpu *vcpu)
1662 {
1663         DEFINE_WAIT(wait);
1664
1665         for (;;) {
1666                 prepare_to_wait(&vcpu->wq, &wait, TASK_INTERRUPTIBLE);
1667
1668                 if (kvm_arch_vcpu_runnable(vcpu)) {
1669                         kvm_make_request(KVM_REQ_UNHALT, vcpu);
1670                         break;
1671                 }
1672                 if (kvm_cpu_has_pending_timer(vcpu))
1673                         break;
1674                 if (signal_pending(current))
1675                         break;
1676
1677                 schedule();
1678         }
1679
1680         finish_wait(&vcpu->wq, &wait);
1681 }
1682
1683 #ifndef CONFIG_S390
1684 /*
1685  * Kick a sleeping VCPU, or a guest VCPU in guest mode, into host kernel mode.
1686  */
1687 void kvm_vcpu_kick(struct kvm_vcpu *vcpu)
1688 {
1689         int me;
1690         int cpu = vcpu->cpu;
1691         wait_queue_head_t *wqp;
1692
1693         wqp = kvm_arch_vcpu_wq(vcpu);
1694         if (waitqueue_active(wqp)) {
1695                 wake_up_interruptible(wqp);
1696                 ++vcpu->stat.halt_wakeup;
1697         }
1698
1699         me = get_cpu();
1700         if (cpu != me && (unsigned)cpu < nr_cpu_ids && cpu_online(cpu))
1701                 if (kvm_arch_vcpu_should_kick(vcpu))
1702                         smp_send_reschedule(cpu);
1703         put_cpu();
1704 }
1705 EXPORT_SYMBOL_GPL(kvm_vcpu_kick);
1706 #endif /* !CONFIG_S390 */
1707
1708 void kvm_resched(struct kvm_vcpu *vcpu)
1709 {
1710         if (!need_resched())
1711                 return;
1712         cond_resched();
1713 }
1714 EXPORT_SYMBOL_GPL(kvm_resched);
1715
1716 bool kvm_vcpu_yield_to(struct kvm_vcpu *target)
1717 {
1718         struct pid *pid;
1719         struct task_struct *task = NULL;
1720         bool ret = false;
1721
1722         rcu_read_lock();
1723         pid = rcu_dereference(target->pid);
1724         if (pid)
1725                 task = get_pid_task(target->pid, PIDTYPE_PID);
1726         rcu_read_unlock();
1727         if (!task)
1728                 return ret;
1729         if (task->flags & PF_VCPU) {
1730                 put_task_struct(task);
1731                 return ret;
1732         }
1733         ret = yield_to(task, 1);
1734         put_task_struct(task);
1735
1736         return ret;
1737 }
1738 EXPORT_SYMBOL_GPL(kvm_vcpu_yield_to);
1739
1740 #ifdef CONFIG_HAVE_KVM_CPU_RELAX_INTERCEPT
1741 /*
1742  * Helper that checks whether a VCPU is eligible for directed yield.
1743  * Most eligible candidate to yield is decided by following heuristics:
1744  *
1745  *  (a) VCPU which has not done pl-exit or cpu relax intercepted recently
1746  *  (preempted lock holder), indicated by @in_spin_loop.
1747  *  Set at the beiginning and cleared at the end of interception/PLE handler.
1748  *
1749  *  (b) VCPU which has done pl-exit/ cpu relax intercepted but did not get
1750  *  chance last time (mostly it has become eligible now since we have probably
1751  *  yielded to lockholder in last iteration. This is done by toggling
1752  *  @dy_eligible each time a VCPU checked for eligibility.)
1753  *
1754  *  Yielding to a recently pl-exited/cpu relax intercepted VCPU before yielding
1755  *  to preempted lock-holder could result in wrong VCPU selection and CPU
1756  *  burning. Giving priority for a potential lock-holder increases lock
1757  *  progress.
1758  *
1759  *  Since algorithm is based on heuristics, accessing another VCPU data without
1760  *  locking does not harm. It may result in trying to yield to  same VCPU, fail
1761  *  and continue with next VCPU and so on.
1762  */
1763 bool kvm_vcpu_eligible_for_directed_yield(struct kvm_vcpu *vcpu)
1764 {
1765         bool eligible;
1766
1767         eligible = !vcpu->spin_loop.in_spin_loop ||
1768                         (vcpu->spin_loop.in_spin_loop &&
1769                          vcpu->spin_loop.dy_eligible);
1770
1771         if (vcpu->spin_loop.in_spin_loop)
1772                 kvm_vcpu_set_dy_eligible(vcpu, !vcpu->spin_loop.dy_eligible);
1773
1774         return eligible;
1775 }
1776 #endif
1777
1778 void kvm_vcpu_on_spin(struct kvm_vcpu *me)
1779 {
1780         struct kvm *kvm = me->kvm;
1781         struct kvm_vcpu *vcpu;
1782         int last_boosted_vcpu = me->kvm->last_boosted_vcpu;
1783         int yielded = 0;
1784         int try = 3;
1785         int pass;
1786         int i;
1787
1788         kvm_vcpu_set_in_spin_loop(me, true);
1789         /*
1790          * We boost the priority of a VCPU that is runnable but not
1791          * currently running, because it got preempted by something
1792          * else and called schedule in __vcpu_run.  Hopefully that
1793          * VCPU is holding the lock that we need and will release it.
1794          * We approximate round-robin by starting at the last boosted VCPU.
1795          */
1796         for (pass = 0; pass < 2 && !yielded && try; pass++) {
1797                 kvm_for_each_vcpu(i, vcpu, kvm) {
1798                         if (!pass && i <= last_boosted_vcpu) {
1799                                 i = last_boosted_vcpu;
1800                                 continue;
1801                         } else if (pass && i > last_boosted_vcpu)
1802                                 break;
1803                         if (!ACCESS_ONCE(vcpu->preempted))
1804                                 continue;
1805                         if (vcpu == me)
1806                                 continue;
1807                         if (waitqueue_active(&vcpu->wq))
1808                                 continue;
1809                         if (!kvm_vcpu_eligible_for_directed_yield(vcpu))
1810                                 continue;
1811
1812                         yielded = kvm_vcpu_yield_to(vcpu);
1813                         if (yielded > 0) {
1814                                 kvm->last_boosted_vcpu = i;
1815                                 break;
1816                         } else if (yielded < 0) {
1817                                 try--;
1818                                 if (!try)
1819                                         break;
1820                         }
1821                 }
1822         }
1823         kvm_vcpu_set_in_spin_loop(me, false);
1824
1825         /* Ensure vcpu is not eligible during next spinloop */
1826         kvm_vcpu_set_dy_eligible(me, false);
1827 }
1828 EXPORT_SYMBOL_GPL(kvm_vcpu_on_spin);
1829
1830 static int kvm_vcpu_fault(struct vm_area_struct *vma, struct vm_fault *vmf)
1831 {
1832         struct kvm_vcpu *vcpu = vma->vm_file->private_data;
1833         struct page *page;
1834
1835         if (vmf->pgoff == 0)
1836                 page = virt_to_page(vcpu->run);
1837 #ifdef CONFIG_X86
1838         else if (vmf->pgoff == KVM_PIO_PAGE_OFFSET)
1839                 page = virt_to_page(vcpu->arch.pio_data);
1840 #endif
1841 #ifdef KVM_COALESCED_MMIO_PAGE_OFFSET
1842         else if (vmf->pgoff == KVM_COALESCED_MMIO_PAGE_OFFSET)
1843                 page = virt_to_page(vcpu->kvm->coalesced_mmio_ring);
1844 #endif
1845         else
1846                 return kvm_arch_vcpu_fault(vcpu, vmf);
1847         get_page(page);
1848         vmf->page = page;
1849         return 0;
1850 }
1851
1852 static const struct vm_operations_struct kvm_vcpu_vm_ops = {
1853         .fault = kvm_vcpu_fault,
1854 };
1855
1856 static int kvm_vcpu_mmap(struct file *file, struct vm_area_struct *vma)
1857 {
1858         vma->vm_ops = &kvm_vcpu_vm_ops;
1859         return 0;
1860 }
1861
1862 static int kvm_vcpu_release(struct inode *inode, struct file *filp)
1863 {
1864         struct kvm_vcpu *vcpu = filp->private_data;
1865
1866         kvm_put_kvm(vcpu->kvm);
1867         return 0;
1868 }
1869
1870 static struct file_operations kvm_vcpu_fops = {
1871         .release        = kvm_vcpu_release,
1872         .unlocked_ioctl = kvm_vcpu_ioctl,
1873 #ifdef CONFIG_COMPAT
1874         .compat_ioctl   = kvm_vcpu_compat_ioctl,
1875 #endif
1876         .mmap           = kvm_vcpu_mmap,
1877         .llseek         = noop_llseek,
1878 };
1879
1880 /*
1881  * Allocates an inode for the vcpu.
1882  */
1883 static int create_vcpu_fd(struct kvm_vcpu *vcpu)
1884 {
1885         return anon_inode_getfd("kvm-vcpu", &kvm_vcpu_fops, vcpu, O_RDWR | O_CLOEXEC);
1886 }
1887
1888 /*
1889  * Creates some virtual cpus.  Good luck creating more than one.
1890  */
1891 static int kvm_vm_ioctl_create_vcpu(struct kvm *kvm, u32 id)
1892 {
1893         int r;
1894         struct kvm_vcpu *vcpu, *v;
1895
1896         vcpu = kvm_arch_vcpu_create(kvm, id);
1897         if (IS_ERR(vcpu))
1898                 return PTR_ERR(vcpu);
1899
1900         preempt_notifier_init(&vcpu->preempt_notifier, &kvm_preempt_ops);
1901
1902         r = kvm_arch_vcpu_setup(vcpu);
1903         if (r)
1904                 goto vcpu_destroy;
1905
1906         mutex_lock(&kvm->lock);
1907         if (!kvm_vcpu_compatible(vcpu)) {
1908                 r = -EINVAL;
1909                 goto unlock_vcpu_destroy;
1910         }
1911         if (atomic_read(&kvm->online_vcpus) == KVM_MAX_VCPUS) {
1912                 r = -EINVAL;
1913                 goto unlock_vcpu_destroy;
1914         }
1915
1916         kvm_for_each_vcpu(r, v, kvm)
1917                 if (v->vcpu_id == id) {
1918                         r = -EEXIST;
1919                         goto unlock_vcpu_destroy;
1920                 }
1921
1922         BUG_ON(kvm->vcpus[atomic_read(&kvm->online_vcpus)]);
1923
1924         /* Now it's all set up, let userspace reach it */
1925         kvm_get_kvm(kvm);
1926         r = create_vcpu_fd(vcpu);
1927         if (r < 0) {
1928                 kvm_put_kvm(kvm);
1929                 goto unlock_vcpu_destroy;
1930         }
1931
1932         kvm->vcpus[atomic_read(&kvm->online_vcpus)] = vcpu;
1933         smp_wmb();
1934         atomic_inc(&kvm->online_vcpus);
1935
1936         mutex_unlock(&kvm->lock);
1937         kvm_arch_vcpu_postcreate(vcpu);
1938         return r;
1939
1940 unlock_vcpu_destroy:
1941         mutex_unlock(&kvm->lock);
1942 vcpu_destroy:
1943         kvm_arch_vcpu_destroy(vcpu);
1944         return r;
1945 }
1946
1947 static int kvm_vcpu_ioctl_set_sigmask(struct kvm_vcpu *vcpu, sigset_t *sigset)
1948 {
1949         if (sigset) {
1950                 sigdelsetmask(sigset, sigmask(SIGKILL)|sigmask(SIGSTOP));
1951                 vcpu->sigset_active = 1;
1952                 vcpu->sigset = *sigset;
1953         } else
1954                 vcpu->sigset_active = 0;
1955         return 0;
1956 }
1957
1958 static long kvm_vcpu_ioctl(struct file *filp,
1959                            unsigned int ioctl, unsigned long arg)
1960 {
1961         struct kvm_vcpu *vcpu = filp->private_data;
1962         void __user *argp = (void __user *)arg;
1963         int r;
1964         struct kvm_fpu *fpu = NULL;
1965         struct kvm_sregs *kvm_sregs = NULL;
1966
1967         if (vcpu->kvm->mm != current->mm)
1968                 return -EIO;
1969
1970 #if defined(CONFIG_S390) || defined(CONFIG_PPC) || defined(CONFIG_MIPS)
1971         /*
1972          * Special cases: vcpu ioctls that are asynchronous to vcpu execution,
1973          * so vcpu_load() would break it.
1974          */
1975         if (ioctl == KVM_S390_INTERRUPT || ioctl == KVM_INTERRUPT)
1976                 return kvm_arch_vcpu_ioctl(filp, ioctl, arg);
1977 #endif
1978
1979
1980         r = vcpu_load(vcpu);
1981         if (r)
1982                 return r;
1983         switch (ioctl) {
1984         case KVM_RUN:
1985                 r = -EINVAL;
1986                 if (arg)
1987                         goto out;
1988                 r = kvm_arch_vcpu_ioctl_run(vcpu, vcpu->run);
1989                 trace_kvm_userspace_exit(vcpu->run->exit_reason, r);
1990                 break;
1991         case KVM_GET_REGS: {
1992                 struct kvm_regs *kvm_regs;
1993
1994                 r = -ENOMEM;
1995                 kvm_regs = kzalloc(sizeof(struct kvm_regs), GFP_KERNEL);
1996                 if (!kvm_regs)
1997                         goto out;
1998                 r = kvm_arch_vcpu_ioctl_get_regs(vcpu, kvm_regs);
1999                 if (r)
2000                         goto out_free1;
2001                 r = -EFAULT;
2002                 if (copy_to_user(argp, kvm_regs, sizeof(struct kvm_regs)))
2003                         goto out_free1;
2004                 r = 0;
2005 out_free1:
2006                 kfree(kvm_regs);
2007                 break;
2008         }
2009         case KVM_SET_REGS: {
2010                 struct kvm_regs *kvm_regs;
2011
2012                 r = -ENOMEM;
2013                 kvm_regs = memdup_user(argp, sizeof(*kvm_regs));
2014                 if (IS_ERR(kvm_regs)) {
2015                         r = PTR_ERR(kvm_regs);
2016                         goto out;
2017                 }
2018                 r = kvm_arch_vcpu_ioctl_set_regs(vcpu, kvm_regs);
2019                 kfree(kvm_regs);
2020                 break;
2021         }
2022         case KVM_GET_SREGS: {
2023                 kvm_sregs = kzalloc(sizeof(struct kvm_sregs), GFP_KERNEL);
2024                 r = -ENOMEM;
2025                 if (!kvm_sregs)
2026                         goto out;
2027                 r = kvm_arch_vcpu_ioctl_get_sregs(vcpu, kvm_sregs);
2028                 if (r)
2029                         goto out;
2030                 r = -EFAULT;
2031                 if (copy_to_user(argp, kvm_sregs, sizeof(struct kvm_sregs)))
2032                         goto out;
2033                 r = 0;
2034                 break;
2035         }
2036         case KVM_SET_SREGS: {
2037                 kvm_sregs = memdup_user(argp, sizeof(*kvm_sregs));
2038                 if (IS_ERR(kvm_sregs)) {
2039                         r = PTR_ERR(kvm_sregs);
2040                         kvm_sregs = NULL;
2041                         goto out;
2042                 }
2043                 r = kvm_arch_vcpu_ioctl_set_sregs(vcpu, kvm_sregs);
2044                 break;
2045         }
2046         case KVM_GET_MP_STATE: {
2047                 struct kvm_mp_state mp_state;
2048
2049                 r = kvm_arch_vcpu_ioctl_get_mpstate(vcpu, &mp_state);
2050                 if (r)
2051                         goto out;
2052                 r = -EFAULT;
2053                 if (copy_to_user(argp, &mp_state, sizeof mp_state))
2054                         goto out;
2055                 r = 0;
2056                 break;
2057         }
2058         case KVM_SET_MP_STATE: {
2059                 struct kvm_mp_state mp_state;
2060
2061                 r = -EFAULT;
2062                 if (copy_from_user(&mp_state, argp, sizeof mp_state))
2063                         goto out;
2064                 r = kvm_arch_vcpu_ioctl_set_mpstate(vcpu, &mp_state);
2065                 break;
2066         }
2067         case KVM_TRANSLATE: {
2068                 struct kvm_translation tr;
2069
2070                 r = -EFAULT;
2071                 if (copy_from_user(&tr, argp, sizeof tr))
2072                         goto out;
2073                 r = kvm_arch_vcpu_ioctl_translate(vcpu, &tr);
2074                 if (r)
2075                         goto out;
2076                 r = -EFAULT;
2077                 if (copy_to_user(argp, &tr, sizeof tr))
2078                         goto out;
2079                 r = 0;
2080                 break;
2081         }
2082         case KVM_SET_GUEST_DEBUG: {
2083                 struct kvm_guest_debug dbg;
2084
2085                 r = -EFAULT;
2086                 if (copy_from_user(&dbg, argp, sizeof dbg))
2087                         goto out;
2088                 r = kvm_arch_vcpu_ioctl_set_guest_debug(vcpu, &dbg);
2089                 break;
2090         }
2091         case KVM_SET_SIGNAL_MASK: {
2092                 struct kvm_signal_mask __user *sigmask_arg = argp;
2093                 struct kvm_signal_mask kvm_sigmask;
2094                 sigset_t sigset, *p;
2095
2096                 p = NULL;
2097                 if (argp) {
2098                         r = -EFAULT;
2099                         if (copy_from_user(&kvm_sigmask, argp,
2100                                            sizeof kvm_sigmask))
2101                                 goto out;
2102                         r = -EINVAL;
2103                         if (kvm_sigmask.len != sizeof sigset)
2104                                 goto out;
2105                         r = -EFAULT;
2106                         if (copy_from_user(&sigset, sigmask_arg->sigset,
2107                                            sizeof sigset))
2108                                 goto out;
2109                         p = &sigset;
2110                 }
2111                 r = kvm_vcpu_ioctl_set_sigmask(vcpu, p);
2112                 break;
2113         }
2114         case KVM_GET_FPU: {
2115                 fpu = kzalloc(sizeof(struct kvm_fpu), GFP_KERNEL);
2116                 r = -ENOMEM;
2117                 if (!fpu)
2118                         goto out;
2119                 r = kvm_arch_vcpu_ioctl_get_fpu(vcpu, fpu);
2120                 if (r)
2121                         goto out;
2122                 r = -EFAULT;
2123                 if (copy_to_user(argp, fpu, sizeof(struct kvm_fpu)))
2124                         goto out;
2125                 r = 0;
2126                 break;
2127         }
2128         case KVM_SET_FPU: {
2129                 fpu = memdup_user(argp, sizeof(*fpu));
2130                 if (IS_ERR(fpu)) {
2131                         r = PTR_ERR(fpu);
2132                         fpu = NULL;
2133                         goto out;
2134                 }
2135                 r = kvm_arch_vcpu_ioctl_set_fpu(vcpu, fpu);
2136                 break;
2137         }
2138         default:
2139                 r = kvm_arch_vcpu_ioctl(filp, ioctl, arg);
2140         }
2141 out:
2142         vcpu_put(vcpu);
2143         kfree(fpu);
2144         kfree(kvm_sregs);
2145         return r;
2146 }
2147
2148 #ifdef CONFIG_COMPAT
2149 static long kvm_vcpu_compat_ioctl(struct file *filp,
2150                                   unsigned int ioctl, unsigned long arg)
2151 {
2152         struct kvm_vcpu *vcpu = filp->private_data;
2153         void __user *argp = compat_ptr(arg);
2154         int r;
2155
2156         if (vcpu->kvm->mm != current->mm)
2157                 return -EIO;
2158
2159         switch (ioctl) {
2160         case KVM_SET_SIGNAL_MASK: {
2161                 struct kvm_signal_mask __user *sigmask_arg = argp;
2162                 struct kvm_signal_mask kvm_sigmask;
2163                 compat_sigset_t csigset;
2164                 sigset_t sigset;
2165
2166                 if (argp) {
2167                         r = -EFAULT;
2168                         if (copy_from_user(&kvm_sigmask, argp,
2169                                            sizeof kvm_sigmask))
2170                                 goto out;
2171                         r = -EINVAL;
2172                         if (kvm_sigmask.len != sizeof csigset)
2173                                 goto out;
2174                         r = -EFAULT;
2175                         if (copy_from_user(&csigset, sigmask_arg->sigset,
2176                                            sizeof csigset))
2177                                 goto out;
2178                         sigset_from_compat(&sigset, &csigset);
2179                         r = kvm_vcpu_ioctl_set_sigmask(vcpu, &sigset);
2180                 } else
2181                         r = kvm_vcpu_ioctl_set_sigmask(vcpu, NULL);
2182                 break;
2183         }
2184         default:
2185                 r = kvm_vcpu_ioctl(filp, ioctl, arg);
2186         }
2187
2188 out:
2189         return r;
2190 }
2191 #endif
2192
2193 static int kvm_device_ioctl_attr(struct kvm_device *dev,
2194                                  int (*accessor)(struct kvm_device *dev,
2195                                                  struct kvm_device_attr *attr),
2196                                  unsigned long arg)
2197 {
2198         struct kvm_device_attr attr;
2199
2200         if (!accessor)
2201                 return -EPERM;
2202
2203         if (copy_from_user(&attr, (void __user *)arg, sizeof(attr)))
2204                 return -EFAULT;
2205
2206         return accessor(dev, &attr);
2207 }
2208
2209 static long kvm_device_ioctl(struct file *filp, unsigned int ioctl,
2210                              unsigned long arg)
2211 {
2212         struct kvm_device *dev = filp->private_data;
2213
2214         switch (ioctl) {
2215         case KVM_SET_DEVICE_ATTR:
2216                 return kvm_device_ioctl_attr(dev, dev->ops->set_attr, arg);
2217         case KVM_GET_DEVICE_ATTR:
2218                 return kvm_device_ioctl_attr(dev, dev->ops->get_attr, arg);
2219         case KVM_HAS_DEVICE_ATTR:
2220                 return kvm_device_ioctl_attr(dev, dev->ops->has_attr, arg);
2221         default:
2222                 if (dev->ops->ioctl)
2223                         return dev->ops->ioctl(dev, ioctl, arg);
2224
2225                 return -ENOTTY;
2226         }
2227 }
2228
2229 static int kvm_device_release(struct inode *inode, struct file *filp)
2230 {
2231         struct kvm_device *dev = filp->private_data;
2232         struct kvm *kvm = dev->kvm;
2233
2234         kvm_put_kvm(kvm);
2235         return 0;
2236 }
2237
2238 static const struct file_operations kvm_device_fops = {
2239         .unlocked_ioctl = kvm_device_ioctl,
2240 #ifdef CONFIG_COMPAT
2241         .compat_ioctl = kvm_device_ioctl,
2242 #endif
2243         .release = kvm_device_release,
2244 };
2245
2246 struct kvm_device *kvm_device_from_filp(struct file *filp)
2247 {
2248         if (filp->f_op != &kvm_device_fops)
2249                 return NULL;
2250
2251         return filp->private_data;
2252 }
2253
2254 static int kvm_ioctl_create_device(struct kvm *kvm,
2255                                    struct kvm_create_device *cd)
2256 {
2257         struct kvm_device_ops *ops = NULL;
2258         struct kvm_device *dev;
2259         bool test = cd->flags & KVM_CREATE_DEVICE_TEST;
2260         int ret;
2261
2262         switch (cd->type) {
2263 #ifdef CONFIG_KVM_MPIC
2264         case KVM_DEV_TYPE_FSL_MPIC_20:
2265         case KVM_DEV_TYPE_FSL_MPIC_42:
2266                 ops = &kvm_mpic_ops;
2267                 break;
2268 #endif
2269 #ifdef CONFIG_KVM_XICS
2270         case KVM_DEV_TYPE_XICS:
2271                 ops = &kvm_xics_ops;
2272                 break;
2273 #endif
2274         default:
2275                 return -ENODEV;
2276         }
2277
2278         if (test)
2279                 return 0;
2280
2281         dev = kzalloc(sizeof(*dev), GFP_KERNEL);
2282         if (!dev)
2283                 return -ENOMEM;
2284
2285         dev->ops = ops;
2286         dev->kvm = kvm;
2287
2288         ret = ops->create(dev, cd->type);
2289         if (ret < 0) {
2290                 kfree(dev);
2291                 return ret;
2292         }
2293
2294         ret = anon_inode_getfd(ops->name, &kvm_device_fops, dev, O_RDWR | O_CLOEXEC);
2295         if (ret < 0) {
2296                 ops->destroy(dev);
2297                 return ret;
2298         }
2299
2300         list_add(&dev->vm_node, &kvm->devices);
2301         kvm_get_kvm(kvm);
2302         cd->fd = ret;
2303         return 0;
2304 }
2305
2306 static long kvm_vm_ioctl(struct file *filp,
2307                            unsigned int ioctl, unsigned long arg)
2308 {
2309         struct kvm *kvm = filp->private_data;
2310         void __user *argp = (void __user *)arg;
2311         int r;
2312
2313         if (kvm->mm != current->mm)
2314                 return -EIO;
2315         switch (ioctl) {
2316         case KVM_CREATE_VCPU:
2317                 r = kvm_vm_ioctl_create_vcpu(kvm, arg);
2318                 break;
2319         case KVM_SET_USER_MEMORY_REGION: {
2320                 struct kvm_userspace_memory_region kvm_userspace_mem;
2321
2322                 r = -EFAULT;
2323                 if (copy_from_user(&kvm_userspace_mem, argp,
2324                                                 sizeof kvm_userspace_mem))
2325                         goto out;
2326
2327                 r = kvm_vm_ioctl_set_memory_region(kvm, &kvm_userspace_mem);
2328                 break;
2329         }
2330         case KVM_GET_DIRTY_LOG: {
2331                 struct kvm_dirty_log log;
2332
2333                 r = -EFAULT;
2334                 if (copy_from_user(&log, argp, sizeof log))
2335                         goto out;
2336                 r = kvm_vm_ioctl_get_dirty_log(kvm, &log);
2337                 break;
2338         }
2339 #ifdef KVM_COALESCED_MMIO_PAGE_OFFSET
2340         case KVM_REGISTER_COALESCED_MMIO: {
2341                 struct kvm_coalesced_mmio_zone zone;
2342                 r = -EFAULT;
2343                 if (copy_from_user(&zone, argp, sizeof zone))
2344                         goto out;
2345                 r = kvm_vm_ioctl_register_coalesced_mmio(kvm, &zone);
2346                 break;
2347         }
2348         case KVM_UNREGISTER_COALESCED_MMIO: {
2349                 struct kvm_coalesced_mmio_zone zone;
2350                 r = -EFAULT;
2351                 if (copy_from_user(&zone, argp, sizeof zone))
2352                         goto out;
2353                 r = kvm_vm_ioctl_unregister_coalesced_mmio(kvm, &zone);
2354                 break;
2355         }
2356 #endif
2357         case KVM_IRQFD: {
2358                 struct kvm_irqfd data;
2359
2360                 r = -EFAULT;
2361                 if (copy_from_user(&data, argp, sizeof data))
2362                         goto out;
2363                 r = kvm_irqfd(kvm, &data);
2364                 break;
2365         }
2366         case KVM_IOEVENTFD: {
2367                 struct kvm_ioeventfd data;
2368
2369                 r = -EFAULT;
2370                 if (copy_from_user(&data, argp, sizeof data))
2371                         goto out;
2372                 r = kvm_ioeventfd(kvm, &data);
2373                 break;
2374         }
2375 #ifdef CONFIG_KVM_APIC_ARCHITECTURE
2376         case KVM_SET_BOOT_CPU_ID:
2377                 r = 0;
2378                 mutex_lock(&kvm->lock);
2379                 if (atomic_read(&kvm->online_vcpus) != 0)
2380                         r = -EBUSY;
2381                 else
2382                         kvm->bsp_vcpu_id = arg;
2383                 mutex_unlock(&kvm->lock);
2384                 break;
2385 #endif
2386 #ifdef CONFIG_HAVE_KVM_MSI
2387         case KVM_SIGNAL_MSI: {
2388                 struct kvm_msi msi;
2389
2390                 r = -EFAULT;
2391                 if (copy_from_user(&msi, argp, sizeof msi))
2392                         goto out;
2393                 r = kvm_send_userspace_msi(kvm, &msi);
2394                 break;
2395         }
2396 #endif
2397 #ifdef __KVM_HAVE_IRQ_LINE
2398         case KVM_IRQ_LINE_STATUS:
2399         case KVM_IRQ_LINE: {
2400                 struct kvm_irq_level irq_event;
2401
2402                 r = -EFAULT;
2403                 if (copy_from_user(&irq_event, argp, sizeof irq_event))
2404                         goto out;
2405
2406                 r = kvm_vm_ioctl_irq_line(kvm, &irq_event,
2407                                         ioctl == KVM_IRQ_LINE_STATUS);
2408                 if (r)
2409                         goto out;
2410
2411                 r = -EFAULT;
2412                 if (ioctl == KVM_IRQ_LINE_STATUS) {
2413                         if (copy_to_user(argp, &irq_event, sizeof irq_event))
2414                                 goto out;
2415                 }
2416
2417                 r = 0;
2418                 break;
2419         }
2420 #endif
2421 #ifdef CONFIG_HAVE_KVM_IRQ_ROUTING
2422         case KVM_SET_GSI_ROUTING: {
2423                 struct kvm_irq_routing routing;
2424                 struct kvm_irq_routing __user *urouting;
2425                 struct kvm_irq_routing_entry *entries;
2426
2427                 r = -EFAULT;
2428                 if (copy_from_user(&routing, argp, sizeof(routing)))
2429                         goto out;
2430                 r = -EINVAL;
2431                 if (routing.nr >= KVM_MAX_IRQ_ROUTES)
2432                         goto out;
2433                 if (routing.flags)
2434                         goto out;
2435                 r = -ENOMEM;
2436                 entries = vmalloc(routing.nr * sizeof(*entries));
2437                 if (!entries)
2438                         goto out;
2439                 r = -EFAULT;
2440                 urouting = argp;
2441                 if (copy_from_user(entries, urouting->entries,
2442                                    routing.nr * sizeof(*entries)))
2443                         goto out_free_irq_routing;
2444                 r = kvm_set_irq_routing(kvm, entries, routing.nr,
2445                                         routing.flags);
2446         out_free_irq_routing:
2447                 vfree(entries);
2448                 break;
2449         }
2450 #endif /* CONFIG_HAVE_KVM_IRQ_ROUTING */
2451         case KVM_CREATE_DEVICE: {
2452                 struct kvm_create_device cd;
2453
2454                 r = -EFAULT;
2455                 if (copy_from_user(&cd, argp, sizeof(cd)))
2456                         goto out;
2457
2458                 r = kvm_ioctl_create_device(kvm, &cd);
2459                 if (r)
2460                         goto out;
2461
2462                 r = -EFAULT;
2463                 if (copy_to_user(argp, &cd, sizeof(cd)))
2464                         goto out;
2465
2466                 r = 0;
2467                 break;
2468         }
2469         default:
2470                 r = kvm_arch_vm_ioctl(filp, ioctl, arg);
2471                 if (r == -ENOTTY)
2472                         r = kvm_vm_ioctl_assigned_device(kvm, ioctl, arg);
2473         }
2474 out:
2475         return r;
2476 }
2477
2478 #ifdef CONFIG_COMPAT
2479 struct compat_kvm_dirty_log {
2480         __u32 slot;
2481         __u32 padding1;
2482         union {
2483                 compat_uptr_t dirty_bitmap; /* one bit per page */
2484                 __u64 padding2;
2485         };
2486 };
2487
2488 static long kvm_vm_compat_ioctl(struct file *filp,
2489                            unsigned int ioctl, unsigned long arg)
2490 {
2491         struct kvm *kvm = filp->private_data;
2492         int r;
2493
2494         if (kvm->mm != current->mm)
2495                 return -EIO;
2496         switch (ioctl) {
2497         case KVM_GET_DIRTY_LOG: {
2498                 struct compat_kvm_dirty_log compat_log;
2499                 struct kvm_dirty_log log;
2500
2501                 r = -EFAULT;
2502                 if (copy_from_user(&compat_log, (void __user *)arg,
2503                                    sizeof(compat_log)))
2504                         goto out;
2505                 log.slot         = compat_log.slot;
2506                 log.padding1     = compat_log.padding1;
2507                 log.padding2     = compat_log.padding2;
2508                 log.dirty_bitmap = compat_ptr(compat_log.dirty_bitmap);
2509
2510                 r = kvm_vm_ioctl_get_dirty_log(kvm, &log);
2511                 break;
2512         }
2513         default:
2514                 r = kvm_vm_ioctl(filp, ioctl, arg);
2515         }
2516
2517 out:
2518         return r;
2519 }
2520 #endif
2521
2522 static int kvm_vm_fault(struct vm_area_struct *vma, struct vm_fault *vmf)
2523 {
2524         struct page *page[1];
2525         unsigned long addr;
2526         int npages;
2527         gfn_t gfn = vmf->pgoff;
2528         struct kvm *kvm = vma->vm_file->private_data;
2529
2530         addr = gfn_to_hva(kvm, gfn);
2531         if (kvm_is_error_hva(addr))
2532                 return VM_FAULT_SIGBUS;
2533
2534         npages = get_user_pages(current, current->mm, addr, 1, 1, 0, page,
2535                                 NULL);
2536         if (unlikely(npages != 1))
2537                 return VM_FAULT_SIGBUS;
2538
2539         vmf->page = page[0];
2540         return 0;
2541 }
2542
2543 static const struct vm_operations_struct kvm_vm_vm_ops = {
2544         .fault = kvm_vm_fault,
2545 };
2546
2547 static int kvm_vm_mmap(struct file *file, struct vm_area_struct *vma)
2548 {
2549         vma->vm_ops = &kvm_vm_vm_ops;
2550         return 0;
2551 }
2552
2553 static struct file_operations kvm_vm_fops = {
2554         .release        = kvm_vm_release,
2555         .unlocked_ioctl = kvm_vm_ioctl,
2556 #ifdef CONFIG_COMPAT
2557         .compat_ioctl   = kvm_vm_compat_ioctl,
2558 #endif
2559         .mmap           = kvm_vm_mmap,
2560         .llseek         = noop_llseek,
2561 };
2562
2563 static int kvm_dev_ioctl_create_vm(unsigned long type)
2564 {
2565         int r;
2566         struct kvm *kvm;
2567
2568         kvm = kvm_create_vm(type);
2569         if (IS_ERR(kvm))
2570                 return PTR_ERR(kvm);
2571 #ifdef KVM_COALESCED_MMIO_PAGE_OFFSET
2572         r = kvm_coalesced_mmio_init(kvm);
2573         if (r < 0) {
2574                 kvm_put_kvm(kvm);
2575                 return r;
2576         }
2577 #endif
2578         r = anon_inode_getfd("kvm-vm", &kvm_vm_fops, kvm, O_RDWR | O_CLOEXEC);
2579         if (r < 0)
2580                 kvm_put_kvm(kvm);
2581
2582         return r;
2583 }
2584
2585 static long kvm_dev_ioctl_check_extension_generic(long arg)
2586 {
2587         switch (arg) {
2588         case KVM_CAP_USER_MEMORY:
2589         case KVM_CAP_DESTROY_MEMORY_REGION_WORKS:
2590         case KVM_CAP_JOIN_MEMORY_REGIONS_WORKS:
2591 #ifdef CONFIG_KVM_APIC_ARCHITECTURE
2592         case KVM_CAP_SET_BOOT_CPU_ID:
2593 #endif
2594         case KVM_CAP_INTERNAL_ERROR_DATA:
2595 #ifdef CONFIG_HAVE_KVM_MSI
2596         case KVM_CAP_SIGNAL_MSI:
2597 #endif
2598 #ifdef CONFIG_HAVE_KVM_IRQ_ROUTING
2599         case KVM_CAP_IRQFD_RESAMPLE:
2600 #endif
2601                 return 1;
2602 #ifdef CONFIG_HAVE_KVM_IRQ_ROUTING
2603         case KVM_CAP_IRQ_ROUTING:
2604                 return KVM_MAX_IRQ_ROUTES;
2605 #endif
2606         default:
2607                 break;
2608         }
2609         return kvm_dev_ioctl_check_extension(arg);
2610 }
2611
2612 static long kvm_dev_ioctl(struct file *filp,
2613                           unsigned int ioctl, unsigned long arg)
2614 {
2615         long r = -EINVAL;
2616
2617         switch (ioctl) {
2618         case KVM_GET_API_VERSION:
2619                 r = -EINVAL;
2620                 if (arg)
2621                         goto out;
2622                 r = KVM_API_VERSION;
2623                 break;
2624         case KVM_CREATE_VM:
2625                 r = kvm_dev_ioctl_create_vm(arg);
2626                 break;
2627         case KVM_CHECK_EXTENSION:
2628                 r = kvm_dev_ioctl_check_extension_generic(arg);
2629                 break;
2630         case KVM_GET_VCPU_MMAP_SIZE:
2631                 r = -EINVAL;
2632                 if (arg)
2633                         goto out;
2634                 r = PAGE_SIZE;     /* struct kvm_run */
2635 #ifdef CONFIG_X86
2636                 r += PAGE_SIZE;    /* pio data page */
2637 #endif
2638 #ifdef KVM_COALESCED_MMIO_PAGE_OFFSET
2639                 r += PAGE_SIZE;    /* coalesced mmio ring page */
2640 #endif
2641                 break;
2642         case KVM_TRACE_ENABLE:
2643         case KVM_TRACE_PAUSE:
2644         case KVM_TRACE_DISABLE:
2645                 r = -EOPNOTSUPP;
2646                 break;
2647         default:
2648                 return kvm_arch_dev_ioctl(filp, ioctl, arg);
2649         }
2650 out:
2651         return r;
2652 }
2653
2654 static struct file_operations kvm_chardev_ops = {
2655         .unlocked_ioctl = kvm_dev_ioctl,
2656         .compat_ioctl   = kvm_dev_ioctl,
2657         .llseek         = noop_llseek,
2658 };
2659
2660 static struct miscdevice kvm_dev = {
2661         KVM_MINOR,
2662         "kvm",
2663         &kvm_chardev_ops,
2664 };
2665
2666 static void hardware_enable_nolock(void *junk)
2667 {
2668         int cpu = raw_smp_processor_id();
2669         int r;
2670
2671         if (cpumask_test_cpu(cpu, cpus_hardware_enabled))
2672                 return;
2673
2674         cpumask_set_cpu(cpu, cpus_hardware_enabled);
2675
2676         r = kvm_arch_hardware_enable(NULL);
2677
2678         if (r) {
2679                 cpumask_clear_cpu(cpu, cpus_hardware_enabled);
2680                 atomic_inc(&hardware_enable_failed);
2681                 printk(KERN_INFO "kvm: enabling virtualization on "
2682                                  "CPU%d failed\n", cpu);
2683         }
2684 }
2685
2686 static void hardware_enable(void *junk)
2687 {
2688         raw_spin_lock(&kvm_lock);
2689         hardware_enable_nolock(junk);
2690         raw_spin_unlock(&kvm_lock);
2691 }
2692
2693 static void hardware_disable_nolock(void *junk)
2694 {
2695         int cpu = raw_smp_processor_id();
2696
2697         if (!cpumask_test_cpu(cpu, cpus_hardware_enabled))
2698                 return;
2699         cpumask_clear_cpu(cpu, cpus_hardware_enabled);
2700         kvm_arch_hardware_disable(NULL);
2701 }
2702
2703 static void hardware_disable(void *junk)
2704 {
2705         raw_spin_lock(&kvm_lock);
2706         hardware_disable_nolock(junk);
2707         raw_spin_unlock(&kvm_lock);
2708 }
2709
2710 static void hardware_disable_all_nolock(void)
2711 {
2712         BUG_ON(!kvm_usage_count);
2713
2714         kvm_usage_count--;
2715         if (!kvm_usage_count)
2716                 on_each_cpu(hardware_disable_nolock, NULL, 1);
2717 }
2718
2719 static void hardware_disable_all(void)
2720 {
2721         raw_spin_lock(&kvm_lock);
2722         hardware_disable_all_nolock();
2723         raw_spin_unlock(&kvm_lock);
2724 }
2725
2726 static int hardware_enable_all(void)
2727 {
2728         int r = 0;
2729
2730         raw_spin_lock(&kvm_lock);
2731
2732         kvm_usage_count++;
2733         if (kvm_usage_count == 1) {
2734                 atomic_set(&hardware_enable_failed, 0);
2735                 on_each_cpu(hardware_enable_nolock, NULL, 1);
2736
2737                 if (atomic_read(&hardware_enable_failed)) {
2738                         hardware_disable_all_nolock();
2739                         r = -EBUSY;
2740                 }
2741         }
2742
2743         raw_spin_unlock(&kvm_lock);
2744
2745         return r;
2746 }
2747
2748 static int kvm_cpu_hotplug(struct notifier_block *notifier, unsigned long val,
2749                            void *v)
2750 {
2751         int cpu = (long)v;
2752
2753         if (!kvm_usage_count)
2754                 return NOTIFY_OK;
2755
2756         val &= ~CPU_TASKS_FROZEN;
2757         switch (val) {
2758         case CPU_DYING:
2759                 printk(KERN_INFO "kvm: disabling virtualization on CPU%d\n",
2760                        cpu);
2761                 hardware_disable(NULL);
2762                 break;
2763         case CPU_STARTING:
2764                 printk(KERN_INFO "kvm: enabling virtualization on CPU%d\n",
2765                        cpu);
2766                 hardware_enable(NULL);
2767                 break;
2768         }
2769         return NOTIFY_OK;
2770 }
2771
2772 static int kvm_reboot(struct notifier_block *notifier, unsigned long val,
2773                       void *v)
2774 {
2775         /*
2776          * Some (well, at least mine) BIOSes hang on reboot if
2777          * in vmx root mode.
2778          *
2779          * And Intel TXT required VMX off for all cpu when system shutdown.
2780          */
2781         printk(KERN_INFO "kvm: exiting hardware virtualization\n");
2782         kvm_rebooting = true;
2783         on_each_cpu(hardware_disable_nolock, NULL, 1);
2784         return NOTIFY_OK;
2785 }
2786
2787 static struct notifier_block kvm_reboot_notifier = {
2788         .notifier_call = kvm_reboot,
2789         .priority = 0,
2790 };
2791
2792 static void kvm_io_bus_destroy(struct kvm_io_bus *bus)
2793 {
2794         int i;
2795
2796         for (i = 0; i < bus->dev_count; i++) {
2797                 struct kvm_io_device *pos = bus->range[i].dev;
2798
2799                 kvm_iodevice_destructor(pos);
2800         }
2801         kfree(bus);
2802 }
2803
2804 static inline int kvm_io_bus_cmp(const struct kvm_io_range *r1,
2805                                  const struct kvm_io_range *r2)
2806 {
2807         if (r1->addr < r2->addr)
2808                 return -1;
2809         if (r1->addr + r1->len > r2->addr + r2->len)
2810                 return 1;
2811         return 0;
2812 }
2813
2814 static int kvm_io_bus_sort_cmp(const void *p1, const void *p2)
2815 {
2816         return kvm_io_bus_cmp(p1, p2);
2817 }
2818
2819 static int kvm_io_bus_insert_dev(struct kvm_io_bus *bus, struct kvm_io_device *dev,
2820                           gpa_t addr, int len)
2821 {
2822         bus->range[bus->dev_count++] = (struct kvm_io_range) {
2823                 .addr = addr,
2824                 .len = len,
2825                 .dev = dev,
2826         };
2827
2828         sort(bus->range, bus->dev_count, sizeof(struct kvm_io_range),
2829                 kvm_io_bus_sort_cmp, NULL);
2830
2831         return 0;
2832 }
2833
2834 static int kvm_io_bus_get_first_dev(struct kvm_io_bus *bus,
2835                              gpa_t addr, int len)
2836 {
2837         struct kvm_io_range *range, key;
2838         int off;
2839
2840         key = (struct kvm_io_range) {
2841                 .addr = addr,
2842                 .len = len,
2843         };
2844
2845         range = bsearch(&key, bus->range, bus->dev_count,
2846                         sizeof(struct kvm_io_range), kvm_io_bus_sort_cmp);
2847         if (range == NULL)
2848                 return -ENOENT;
2849
2850         off = range - bus->range;
2851
2852         while (off > 0 && kvm_io_bus_cmp(&key, &bus->range[off-1]) == 0)
2853                 off--;
2854
2855         return off;
2856 }
2857
2858 static int __kvm_io_bus_write(struct kvm_io_bus *bus,
2859                               struct kvm_io_range *range, const void *val)
2860 {
2861         int idx;
2862
2863         idx = kvm_io_bus_get_first_dev(bus, range->addr, range->len);
2864         if (idx < 0)
2865                 return -EOPNOTSUPP;
2866
2867         while (idx < bus->dev_count &&
2868                 kvm_io_bus_cmp(range, &bus->range[idx]) == 0) {
2869                 if (!kvm_iodevice_write(bus->range[idx].dev, range->addr,
2870                                         range->len, val))
2871                         return idx;
2872                 idx++;
2873         }
2874
2875         return -EOPNOTSUPP;
2876 }
2877
2878 /* kvm_io_bus_write - called under kvm->slots_lock */
2879 int kvm_io_bus_write(struct kvm *kvm, enum kvm_bus bus_idx, gpa_t addr,
2880                      int len, const void *val)
2881 {
2882         struct kvm_io_bus *bus;
2883         struct kvm_io_range range;
2884         int r;
2885
2886         range = (struct kvm_io_range) {
2887                 .addr = addr,
2888                 .len = len,
2889         };
2890
2891         bus = srcu_dereference(kvm->buses[bus_idx], &kvm->srcu);
2892         r = __kvm_io_bus_write(bus, &range, val);
2893         return r < 0 ? r : 0;
2894 }
2895
2896 /* kvm_io_bus_write_cookie - called under kvm->slots_lock */
2897 int kvm_io_bus_write_cookie(struct kvm *kvm, enum kvm_bus bus_idx, gpa_t addr,
2898                             int len, const void *val, long cookie)
2899 {
2900         struct kvm_io_bus *bus;
2901         struct kvm_io_range range;
2902
2903         range = (struct kvm_io_range) {
2904                 .addr = addr,
2905                 .len = len,
2906         };
2907
2908         bus = srcu_dereference(kvm->buses[bus_idx], &kvm->srcu);
2909
2910         /* First try the device referenced by cookie. */
2911         if ((cookie >= 0) && (cookie < bus->dev_count) &&
2912             (kvm_io_bus_cmp(&range, &bus->range[cookie]) == 0))
2913                 if (!kvm_iodevice_write(bus->range[cookie].dev, addr, len,
2914                                         val))
2915                         return cookie;
2916
2917         /*
2918          * cookie contained garbage; fall back to search and return the
2919          * correct cookie value.
2920          */
2921         return __kvm_io_bus_write(bus, &range, val);
2922 }
2923
2924 static int __kvm_io_bus_read(struct kvm_io_bus *bus, struct kvm_io_range *range,
2925                              void *val)
2926 {
2927         int idx;
2928
2929         idx = kvm_io_bus_get_first_dev(bus, range->addr, range->len);
2930         if (idx < 0)
2931                 return -EOPNOTSUPP;
2932
2933         while (idx < bus->dev_count &&
2934                 kvm_io_bus_cmp(range, &bus->range[idx]) == 0) {
2935                 if (!kvm_iodevice_read(bus->range[idx].dev, range->addr,
2936                                        range->len, val))
2937                         return idx;
2938                 idx++;
2939         }
2940
2941         return -EOPNOTSUPP;
2942 }
2943
2944 /* kvm_io_bus_read - called under kvm->slots_lock */
2945 int kvm_io_bus_read(struct kvm *kvm, enum kvm_bus bus_idx, gpa_t addr,
2946                     int len, void *val)
2947 {
2948         struct kvm_io_bus *bus;
2949         struct kvm_io_range range;
2950         int r;
2951
2952         range = (struct kvm_io_range) {
2953                 .addr = addr,
2954                 .len = len,
2955         };
2956
2957         bus = srcu_dereference(kvm->buses[bus_idx], &kvm->srcu);
2958         r = __kvm_io_bus_read(bus, &range, val);
2959         return r < 0 ? r : 0;
2960 }
2961
2962 /* kvm_io_bus_read_cookie - called under kvm->slots_lock */
2963 int kvm_io_bus_read_cookie(struct kvm *kvm, enum kvm_bus bus_idx, gpa_t addr,
2964                            int len, void *val, long cookie)
2965 {
2966         struct kvm_io_bus *bus;
2967         struct kvm_io_range range;
2968
2969         range = (struct kvm_io_range) {
2970                 .addr = addr,
2971                 .len = len,
2972         };
2973
2974         bus = srcu_dereference(kvm->buses[bus_idx], &kvm->srcu);
2975
2976         /* First try the device referenced by cookie. */
2977         if ((cookie >= 0) && (cookie < bus->dev_count) &&
2978             (kvm_io_bus_cmp(&range, &bus->range[cookie]) == 0))
2979                 if (!kvm_iodevice_read(bus->range[cookie].dev, addr, len,
2980                                        val))
2981                         return cookie;
2982
2983         /*
2984          * cookie contained garbage; fall back to search and return the
2985          * correct cookie value.
2986          */
2987         return __kvm_io_bus_read(bus, &range, val);
2988 }
2989
2990 /* Caller must hold slots_lock. */
2991 int kvm_io_bus_register_dev(struct kvm *kvm, enum kvm_bus bus_idx, gpa_t addr,
2992                             int len, struct kvm_io_device *dev)
2993 {
2994         struct kvm_io_bus *new_bus, *bus;
2995
2996         bus = kvm->buses[bus_idx];
2997         /* exclude ioeventfd which is limited by maximum fd */
2998         if (bus->dev_count - bus->ioeventfd_count > NR_IOBUS_DEVS - 1)
2999                 return -ENOSPC;
3000
3001         new_bus = kzalloc(sizeof(*bus) + ((bus->dev_count + 1) *
3002                           sizeof(struct kvm_io_range)), GFP_KERNEL);
3003         if (!new_bus)
3004                 return -ENOMEM;
3005         memcpy(new_bus, bus, sizeof(*bus) + (bus->dev_count *
3006                sizeof(struct kvm_io_range)));
3007         kvm_io_bus_insert_dev(new_bus, dev, addr, len);
3008         rcu_assign_pointer(kvm->buses[bus_idx], new_bus);
3009         synchronize_srcu_expedited(&kvm->srcu);
3010         kfree(bus);
3011
3012         return 0;
3013 }
3014
3015 /* Caller must hold slots_lock. */
3016 int kvm_io_bus_unregister_dev(struct kvm *kvm, enum kvm_bus bus_idx,
3017                               struct kvm_io_device *dev)
3018 {
3019         int i, r;
3020         struct kvm_io_bus *new_bus, *bus;
3021
3022         bus = kvm->buses[bus_idx];
3023         r = -ENOENT;
3024         for (i = 0; i < bus->dev_count; i++)
3025                 if (bus->range[i].dev == dev) {
3026                         r = 0;
3027                         break;
3028                 }
3029
3030         if (r)
3031                 return r;
3032
3033         new_bus = kzalloc(sizeof(*bus) + ((bus->dev_count - 1) *
3034                           sizeof(struct kvm_io_range)), GFP_KERNEL);
3035         if (!new_bus)
3036                 return -ENOMEM;
3037
3038         memcpy(new_bus, bus, sizeof(*bus) + i * sizeof(struct kvm_io_range));
3039         new_bus->dev_count--;
3040         memcpy(new_bus->range + i, bus->range + i + 1,
3041                (new_bus->dev_count - i) * sizeof(struct kvm_io_range));
3042
3043         rcu_assign_pointer(kvm->buses[bus_idx], new_bus);
3044         synchronize_srcu_expedited(&kvm->srcu);
3045         kfree(bus);
3046         return r;
3047 }
3048
3049 static struct notifier_block kvm_cpu_notifier = {
3050         .notifier_call = kvm_cpu_hotplug,
3051 };
3052
3053 static int vm_stat_get(void *_offset, u64 *val)
3054 {
3055         unsigned offset = (long)_offset;
3056         struct kvm *kvm;
3057
3058         *val = 0;
3059         raw_spin_lock(&kvm_lock);
3060         list_for_each_entry(kvm, &vm_list, vm_list)
3061                 *val += *(u32 *)((void *)kvm + offset);
3062         raw_spin_unlock(&kvm_lock);
3063         return 0;
3064 }
3065
3066 DEFINE_SIMPLE_ATTRIBUTE(vm_stat_fops, vm_stat_get, NULL, "%llu\n");
3067
3068 static int vcpu_stat_get(void *_offset, u64 *val)
3069 {
3070         unsigned offset = (long)_offset;
3071         struct kvm *kvm;
3072         struct kvm_vcpu *vcpu;
3073         int i;
3074
3075         *val = 0;
3076         raw_spin_lock(&kvm_lock);
3077         list_for_each_entry(kvm, &vm_list, vm_list)
3078                 kvm_for_each_vcpu(i, vcpu, kvm)
3079                         *val += *(u32 *)((void *)vcpu + offset);
3080
3081         raw_spin_unlock(&kvm_lock);
3082         return 0;
3083 }
3084
3085 DEFINE_SIMPLE_ATTRIBUTE(vcpu_stat_fops, vcpu_stat_get, NULL, "%llu\n");
3086
3087 static const struct file_operations *stat_fops[] = {
3088         [KVM_STAT_VCPU] = &vcpu_stat_fops,
3089         [KVM_STAT_VM]   = &vm_stat_fops,
3090 };
3091
3092 static int kvm_init_debug(void)
3093 {
3094         int r = -EFAULT;
3095         struct kvm_stats_debugfs_item *p;
3096
3097         kvm_debugfs_dir = debugfs_create_dir("kvm", NULL);
3098         if (kvm_debugfs_dir == NULL)
3099                 goto out;
3100
3101         for (p = debugfs_entries; p->name; ++p) {
3102                 p->dentry = debugfs_create_file(p->name, 0444, kvm_debugfs_dir,
3103                                                 (void *)(long)p->offset,
3104                                                 stat_fops[p->kind]);
3105                 if (p->dentry == NULL)
3106                         goto out_dir;
3107         }
3108
3109         return 0;
3110
3111 out_dir:
3112         debugfs_remove_recursive(kvm_debugfs_dir);
3113 out:
3114         return r;
3115 }
3116
3117 static void kvm_exit_debug(void)
3118 {
3119         struct kvm_stats_debugfs_item *p;
3120
3121         for (p = debugfs_entries; p->name; ++p)
3122                 debugfs_remove(p->dentry);
3123         debugfs_remove(kvm_debugfs_dir);
3124 }
3125
3126 static int kvm_suspend(void)
3127 {
3128         if (kvm_usage_count)
3129                 hardware_disable_nolock(NULL);
3130         return 0;
3131 }
3132
3133 static void kvm_resume(void)
3134 {
3135         if (kvm_usage_count) {
3136                 WARN_ON(raw_spin_is_locked(&kvm_lock));
3137                 hardware_enable_nolock(NULL);
3138         }
3139 }
3140
3141 static struct syscore_ops kvm_syscore_ops = {
3142         .suspend = kvm_suspend,
3143         .resume = kvm_resume,
3144 };
3145
3146 static inline
3147 struct kvm_vcpu *preempt_notifier_to_vcpu(struct preempt_notifier *pn)
3148 {
3149         return container_of(pn, struct kvm_vcpu, preempt_notifier);
3150 }
3151
3152 static void kvm_sched_in(struct preempt_notifier *pn, int cpu)
3153 {
3154         struct kvm_vcpu *vcpu = preempt_notifier_to_vcpu(pn);
3155         if (vcpu->preempted)
3156                 vcpu->preempted = false;
3157
3158         kvm_arch_vcpu_load(vcpu, cpu);
3159 }
3160
3161 static void kvm_sched_out(struct preempt_notifier *pn,
3162                           struct task_struct *next)
3163 {
3164         struct kvm_vcpu *vcpu = preempt_notifier_to_vcpu(pn);
3165
3166         if (current->state == TASK_RUNNING)
3167                 vcpu->preempted = true;
3168         kvm_arch_vcpu_put(vcpu);
3169 }
3170
3171 int kvm_init(void *opaque, unsigned vcpu_size, unsigned vcpu_align,
3172                   struct module *module)
3173 {
3174         int r;
3175         int cpu;
3176
3177         r = kvm_arch_init(opaque);
3178         if (r)
3179                 goto out_fail;
3180
3181         /*
3182          * kvm_arch_init makes sure there's at most one caller
3183          * for architectures that support multiple implementations,
3184          * like intel and amd on x86.
3185          * kvm_arch_init must be called before kvm_irqfd_init to avoid creating
3186          * conflicts in case kvm is already setup for another implementation.
3187          */
3188         r = kvm_irqfd_init();
3189         if (r)
3190                 goto out_irqfd;
3191
3192         if (!zalloc_cpumask_var(&cpus_hardware_enabled, GFP_KERNEL)) {
3193                 r = -ENOMEM;
3194                 goto out_free_0;
3195         }
3196
3197         r = kvm_arch_hardware_setup();
3198         if (r < 0)
3199                 goto out_free_0a;
3200
3201         for_each_online_cpu(cpu) {
3202                 smp_call_function_single(cpu,
3203                                 kvm_arch_check_processor_compat,
3204                                 &r, 1);
3205                 if (r < 0)
3206                         goto out_free_1;
3207         }
3208
3209         r = register_cpu_notifier(&kvm_cpu_notifier);
3210         if (r)
3211                 goto out_free_2;
3212         register_reboot_notifier(&kvm_reboot_notifier);
3213
3214         /* A kmem cache lets us meet the alignment requirements of fx_save. */
3215         if (!vcpu_align)
3216                 vcpu_align = __alignof__(struct kvm_vcpu);
3217         kvm_vcpu_cache = kmem_cache_create("kvm_vcpu", vcpu_size, vcpu_align,
3218                                            0, NULL);
3219         if (!kvm_vcpu_cache) {
3220                 r = -ENOMEM;
3221                 goto out_free_3;
3222         }
3223
3224         r = kvm_async_pf_init();
3225         if (r)
3226                 goto out_free;
3227
3228         kvm_chardev_ops.owner = module;
3229         kvm_vm_fops.owner = module;
3230         kvm_vcpu_fops.owner = module;
3231
3232         r = misc_register(&kvm_dev);
3233         if (r) {
3234                 printk(KERN_ERR "kvm: misc device register failed\n");
3235                 goto out_unreg;
3236         }
3237
3238         register_syscore_ops(&kvm_syscore_ops);
3239
3240         kvm_preempt_ops.sched_in = kvm_sched_in;
3241         kvm_preempt_ops.sched_out = kvm_sched_out;
3242
3243         r = kvm_init_debug();
3244         if (r) {
3245                 printk(KERN_ERR "kvm: create debugfs files failed\n");
3246                 goto out_undebugfs;
3247         }
3248
3249         return 0;
3250
3251 out_undebugfs:
3252         unregister_syscore_ops(&kvm_syscore_ops);
3253         misc_deregister(&kvm_dev);
3254 out_unreg:
3255         kvm_async_pf_deinit();
3256 out_free:
3257         kmem_cache_destroy(kvm_vcpu_cache);
3258 out_free_3:
3259         unregister_reboot_notifier(&kvm_reboot_notifier);
3260         unregister_cpu_notifier(&kvm_cpu_notifier);
3261 out_free_2:
3262 out_free_1:
3263         kvm_arch_hardware_unsetup();
3264 out_free_0a:
3265         free_cpumask_var(cpus_hardware_enabled);
3266 out_free_0:
3267         kvm_irqfd_exit();
3268 out_irqfd:
3269         kvm_arch_exit();
3270 out_fail:
3271         return r;
3272 }
3273 EXPORT_SYMBOL_GPL(kvm_init);
3274
3275 void kvm_exit(void)
3276 {
3277         kvm_exit_debug();
3278         misc_deregister(&kvm_dev);
3279         kmem_cache_destroy(kvm_vcpu_cache);
3280         kvm_async_pf_deinit();
3281         unregister_syscore_ops(&kvm_syscore_ops);
3282         unregister_reboot_notifier(&kvm_reboot_notifier);
3283         unregister_cpu_notifier(&kvm_cpu_notifier);
3284         on_each_cpu(hardware_disable_nolock, NULL, 1);
3285         kvm_arch_hardware_unsetup();
3286         kvm_arch_exit();
3287         kvm_irqfd_exit();
3288         free_cpumask_var(cpus_hardware_enabled);
3289 }
3290 EXPORT_SYMBOL_GPL(kvm_exit);