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 <kvm/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/ioctl.h>
  56 #include <asm/uaccess.h>
  57 #include <asm/pgtable.h>
  58
  59 #include "coalesced_mmio.h"
  60 #include "async_pf.h"
  61 #include "vfio.h"
  62
  63 #define CREATE_TRACE_POINTS
  64 #include <trace/events/kvm.h>
  65
  66 MODULE_AUTHOR("Qumranet");
  67 MODULE_LICENSE("GPL");
  68
  69 static unsigned int halt_poll_ns;
  70 module_param(halt_poll_ns, uint, S_IRUGO | S_IWUSR);
  71
  72 /*
  73  * Ordering of locks:
  74  *
  75  *      kvm->lock --> kvm->slots_lock --> kvm->irq_lock
  76  */
  77
  78 DEFINE_SPINLOCK(kvm_lock);
  79 static DEFINE_RAW_SPINLOCK(kvm_count_lock);
  80 LIST_HEAD(vm_list);
  81
  82 static cpumask_var_t cpus_hardware_enabled;
  83 static int kvm_usage_count;
  84 static atomic_t hardware_enable_failed;
  85
  86 struct kmem_cache *kvm_vcpu_cache;
  87 EXPORT_SYMBOL_GPL(kvm_vcpu_cache);
  88
  89 static __read_mostly struct preempt_ops kvm_preempt_ops;
  90
  91 struct dentry *kvm_debugfs_dir;
  92
  93 static long kvm_vcpu_ioctl(struct file *file, unsigned int ioctl,
  94                            unsigned long arg);
  95 #ifdef CONFIG_KVM_COMPAT
  96 static long kvm_vcpu_compat_ioctl(struct file *file, unsigned int ioctl,
  97                                   unsigned long arg);
  98 #endif
  99 static int hardware_enable_all(void);
 100 static void hardware_disable_all(void);
 101
 102 static void kvm_io_bus_destroy(struct kvm_io_bus *bus);
 103
 104 static void kvm_release_pfn_dirty(pfn_t pfn);
 105 static void mark_page_dirty_in_slot(struct kvm *kvm,
 106                                     struct kvm_memory_slot *memslot, gfn_t gfn);
 107
 108 __visible bool kvm_rebooting;
 109 EXPORT_SYMBOL_GPL(kvm_rebooting);
 110
 111 static bool largepages_enabled = true;
 112
 113 bool kvm_is_reserved_pfn(pfn_t pfn)
 114 {
 115         if (pfn_valid(pfn))
 116                 return PageReserved(pfn_to_page(pfn));
 117
 118         return true;
 119 }
 120
 121 /*
 122  * Switches to specified vcpu, until a matching vcpu_put()
 123  */
 124 int vcpu_load(struct kvm_vcpu *vcpu)
 125 {
 126         int cpu;
 127
 128         if (mutex_lock_killable(&vcpu->mutex))
 129                 return -EINTR;
 130         cpu = get_cpu();
 131         preempt_notifier_register(&vcpu->preempt_notifier);
 132         kvm_arch_vcpu_load(vcpu, cpu);
 133         put_cpu();
 134         return 0;
 135 }
 136
 137 void vcpu_put(struct kvm_vcpu *vcpu)
 138 {
 139         preempt_disable();
 140         kvm_arch_vcpu_put(vcpu);
 141         preempt_notifier_unregister(&vcpu->preempt_notifier);
 142         preempt_enable();
 143         mutex_unlock(&vcpu->mutex);
 144 }
 145
 146 static void ack_flush(void *_completed)
 147 {
 148 }
 149
 150 bool kvm_make_all_cpus_request(struct kvm *kvm, unsigned int req)
 151 {
 152         int i, cpu, me;
 153         cpumask_var_t cpus;
 154         bool called = true;
 155         struct kvm_vcpu *vcpu;
 156
 157         zalloc_cpumask_var(&cpus, GFP_ATOMIC);
 158
 159         me = get_cpu();
 160         kvm_for_each_vcpu(i, vcpu, kvm) {
 161                 kvm_make_request(req, vcpu);
 162                 cpu = vcpu->cpu;
 163
 164                 /* Set ->requests bit before we read ->mode */
 165                 smp_mb();
 166
 167                 if (cpus != NULL && cpu != -1 && cpu != me &&
 168                       kvm_vcpu_exiting_guest_mode(vcpu) != OUTSIDE_GUEST_MODE)
 169                         cpumask_set_cpu(cpu, cpus);
 170         }
 171         if (unlikely(cpus == NULL))
 172                 smp_call_function_many(cpu_online_mask, ack_flush, NULL, 1);
 173         else if (!cpumask_empty(cpus))
 174                 smp_call_function_many(cpus, ack_flush, NULL, 1);
 175         else
 176                 called = false;
 177         put_cpu();
 178         free_cpumask_var(cpus);
 179         return called;
 180 }
 181
 182 #ifndef CONFIG_HAVE_KVM_ARCH_TLB_FLUSH_ALL
 183 void kvm_flush_remote_tlbs(struct kvm *kvm)
 184 {
 185         long dirty_count = kvm->tlbs_dirty;
 186
 187         smp_mb();
 188         if (kvm_make_all_cpus_request(kvm, KVM_REQ_TLB_FLUSH))
 189                 ++kvm->stat.remote_tlb_flush;
 190         cmpxchg(&kvm->tlbs_dirty, dirty_count, 0);
 191 }
 192 EXPORT_SYMBOL_GPL(kvm_flush_remote_tlbs);
 193 #endif
 194
 195 void kvm_reload_remote_mmus(struct kvm *kvm)
 196 {
 197         kvm_make_all_cpus_request(kvm, KVM_REQ_MMU_RELOAD);
 198 }
 199
 200 void kvm_make_mclock_inprogress_request(struct kvm *kvm)
 201 {
 202         kvm_make_all_cpus_request(kvm, KVM_REQ_MCLOCK_INPROGRESS);
 203 }
 204
 205 void kvm_make_scan_ioapic_request(struct kvm *kvm)
 206 {
 207         kvm_make_all_cpus_request(kvm, KVM_REQ_SCAN_IOAPIC);
 208 }
 209
 210 int kvm_vcpu_init(struct kvm_vcpu *vcpu, struct kvm *kvm, unsigned id)
 211 {
 212         struct page *page;
 213         int r;
 214
 215         mutex_init(&vcpu->mutex);
 216         vcpu->cpu = -1;
 217         vcpu->kvm = kvm;
 218         vcpu->vcpu_id = id;
 219         vcpu->pid = NULL;
 220         init_waitqueue_head(&vcpu->wq);
 221         kvm_async_pf_vcpu_init(vcpu);
 222
 223         page = alloc_page(GFP_KERNEL | __GFP_ZERO);
 224         if (!page) {
 225                 r = -ENOMEM;
 226                 goto fail;
 227         }
 228         vcpu->run = page_address(page);
 229
 230         kvm_vcpu_set_in_spin_loop(vcpu, false);
 231         kvm_vcpu_set_dy_eligible(vcpu, false);
 232         vcpu->preempted = false;
 233
 234         r = kvm_arch_vcpu_init(vcpu);
 235         if (r < 0)
 236                 goto fail_free_run;
 237         return 0;
 238
 239 fail_free_run:
 240         free_page((unsigned long)vcpu->run);
 241 fail:
 242         return r;
 243 }
 244 EXPORT_SYMBOL_GPL(kvm_vcpu_init);
 245
 246 void kvm_vcpu_uninit(struct kvm_vcpu *vcpu)
 247 {
 248         put_pid(vcpu->pid);
 249         kvm_arch_vcpu_uninit(vcpu);
 250         free_page((unsigned long)vcpu->run);
 251 }
 252 EXPORT_SYMBOL_GPL(kvm_vcpu_uninit);
 253
 254 #if defined(CONFIG_MMU_NOTIFIER) && defined(KVM_ARCH_WANT_MMU_NOTIFIER)
 255 static inline struct kvm *mmu_notifier_to_kvm(struct mmu_notifier *mn)
 256 {
 257         return container_of(mn, struct kvm, mmu_notifier);
 258 }
 259
 260 static void kvm_mmu_notifier_invalidate_page(struct mmu_notifier *mn,
 261                                              struct mm_struct *mm,
 262                                              unsigned long address)
 263 {
 264         struct kvm *kvm = mmu_notifier_to_kvm(mn);
 265         int need_tlb_flush, idx;
 266
 267         /*
 268          * When ->invalidate_page runs, the linux pte has been zapped
 269          * already but the page is still allocated until
 270          * ->invalidate_page returns. So if we increase the sequence
 271          * here the kvm page fault will notice if the spte can't be
 272          * established because the page is going to be freed. If
 273          * instead the kvm page fault establishes the spte before
 274          * ->invalidate_page runs, kvm_unmap_hva will release it
 275          * before returning.
 276          *
 277          * The sequence increase only need to be seen at spin_unlock
 278          * time, and not at spin_lock time.
 279          *
 280          * Increasing the sequence after the spin_unlock would be
 281          * unsafe because the kvm page fault could then establish the
 282          * pte after kvm_unmap_hva returned, without noticing the page
 283          * is going to be freed.
 284          */
 285         idx = srcu_read_lock(&kvm->srcu);
 286         spin_lock(&kvm->mmu_lock);
 287
 288         kvm->mmu_notifier_seq++;
 289         need_tlb_flush = kvm_unmap_hva(kvm, address) | kvm->tlbs_dirty;
 290         /* we've to flush the tlb before the pages can be freed */
 291         if (need_tlb_flush)
 292                 kvm_flush_remote_tlbs(kvm);
 293
 294         spin_unlock(&kvm->mmu_lock);
 295
 296         kvm_arch_mmu_notifier_invalidate_page(kvm, address);
 297
 298         srcu_read_unlock(&kvm->srcu, idx);
 299 }
 300
 301 static void kvm_mmu_notifier_change_pte(struct mmu_notifier *mn,
 302                                         struct mm_struct *mm,
 303                                         unsigned long address,
 304                                         pte_t pte)
 305 {
 306         struct kvm *kvm = mmu_notifier_to_kvm(mn);
 307         int idx;
 308
 309         idx = srcu_read_lock(&kvm->srcu);
 310         spin_lock(&kvm->mmu_lock);
 311         kvm->mmu_notifier_seq++;
 312         kvm_set_spte_hva(kvm, address, pte);
 313         spin_unlock(&kvm->mmu_lock);
 314         srcu_read_unlock(&kvm->srcu, idx);
 315 }
 316
 317 static void kvm_mmu_notifier_invalidate_range_start(struct mmu_notifier *mn,
 318                                                     struct mm_struct *mm,
 319                                                     unsigned long start,
 320                                                     unsigned long end)
 321 {
 322         struct kvm *kvm = mmu_notifier_to_kvm(mn);
 323         int need_tlb_flush = 0, idx;
 324
 325         idx = srcu_read_lock(&kvm->srcu);
 326         spin_lock(&kvm->mmu_lock);
 327         /*
 328          * The count increase must become visible at unlock time as no
 329          * spte can be established without taking the mmu_lock and
 330          * count is also read inside the mmu_lock critical section.
 331          */
 332         kvm->mmu_notifier_count++;
 333         need_tlb_flush = kvm_unmap_hva_range(kvm, start, end);
 334         need_tlb_flush |= kvm->tlbs_dirty;
 335         /* we've to flush the tlb before the pages can be freed */
 336         if (need_tlb_flush)
 337                 kvm_flush_remote_tlbs(kvm);
 338
 339         spin_unlock(&kvm->mmu_lock);
 340         srcu_read_unlock(&kvm->srcu, idx);
 341 }
 342
 343 static void kvm_mmu_notifier_invalidate_range_end(struct mmu_notifier *mn,
 344                                                   struct mm_struct *mm,
 345                                                   unsigned long start,
 346                                                   unsigned long end)
 347 {
 348         struct kvm *kvm = mmu_notifier_to_kvm(mn);
 349
 350         spin_lock(&kvm->mmu_lock);
 351         /*
 352          * This sequence increase will notify the kvm page fault that
 353          * the page that is going to be mapped in the spte could have
 354          * been freed.
 355          */
 356         kvm->mmu_notifier_seq++;
 357         smp_wmb();
 358         /*
 359          * The above sequence increase must be visible before the
 360          * below count decrease, which is ensured by the smp_wmb above
 361          * in conjunction with the smp_rmb in mmu_notifier_retry().
 362          */
 363         kvm->mmu_notifier_count--;
 364         spin_unlock(&kvm->mmu_lock);
 365
 366         BUG_ON(kvm->mmu_notifier_count < 0);
 367 }
 368
 369 static int kvm_mmu_notifier_clear_flush_young(struct mmu_notifier *mn,
 370                                               struct mm_struct *mm,
 371                                               unsigned long start,
 372                                               unsigned long end)
 373 {
 374         struct kvm *kvm = mmu_notifier_to_kvm(mn);
 375         int young, idx;
 376
 377         idx = srcu_read_lock(&kvm->srcu);
 378         spin_lock(&kvm->mmu_lock);
 379
 380         young = kvm_age_hva(kvm, start, end);
 381         if (young)
 382                 kvm_flush_remote_tlbs(kvm);
 383
 384         spin_unlock(&kvm->mmu_lock);
 385         srcu_read_unlock(&kvm->srcu, idx);
 386
 387         return young;
 388 }
 389
 390 static int kvm_mmu_notifier_test_young(struct mmu_notifier *mn,
 391                                        struct mm_struct *mm,
 392                                        unsigned long address)
 393 {
 394         struct kvm *kvm = mmu_notifier_to_kvm(mn);
 395         int young, idx;
 396
 397         idx = srcu_read_lock(&kvm->srcu);
 398         spin_lock(&kvm->mmu_lock);
 399         young = kvm_test_age_hva(kvm, address);
 400         spin_unlock(&kvm->mmu_lock);
 401         srcu_read_unlock(&kvm->srcu, idx);
 402
 403         return young;
 404 }
 405
 406 static void kvm_mmu_notifier_release(struct mmu_notifier *mn,
 407                                      struct mm_struct *mm)
 408 {
 409         struct kvm *kvm = mmu_notifier_to_kvm(mn);
 410         int idx;
 411
 412         idx = srcu_read_lock(&kvm->srcu);
 413         kvm_arch_flush_shadow_all(kvm);
 414         srcu_read_unlock(&kvm->srcu, idx);
 415 }
 416
 417 static const struct mmu_notifier_ops kvm_mmu_notifier_ops = {
 418         .invalidate_page        = kvm_mmu_notifier_invalidate_page,
 419         .invalidate_range_start = kvm_mmu_notifier_invalidate_range_start,
 420         .invalidate_range_end   = kvm_mmu_notifier_invalidate_range_end,
 421         .clear_flush_young      = kvm_mmu_notifier_clear_flush_young,
 422         .test_young             = kvm_mmu_notifier_test_young,
 423         .change_pte             = kvm_mmu_notifier_change_pte,
 424         .release                = kvm_mmu_notifier_release,
 425 };
 426
 427 static int kvm_init_mmu_notifier(struct kvm *kvm)
 428 {
 429         kvm->mmu_notifier.ops = &kvm_mmu_notifier_ops;
 430         return mmu_notifier_register(&kvm->mmu_notifier, current->mm);
 431 }
 432
 433 #else  /* !(CONFIG_MMU_NOTIFIER && KVM_ARCH_WANT_MMU_NOTIFIER) */
 434
 435 static int kvm_init_mmu_notifier(struct kvm *kvm)
 436 {
 437         return 0;
 438 }
 439
 440 #endif /* CONFIG_MMU_NOTIFIER && KVM_ARCH_WANT_MMU_NOTIFIER */
 441
 442 static void kvm_init_memslots_id(struct kvm *kvm)
 443 {
 444         int i;
 445         struct kvm_memslots *slots = kvm->memslots;
 446
 447         for (i = 0; i < KVM_MEM_SLOTS_NUM; i++)
 448                 slots->id_to_index[i] = slots->memslots[i].id = i;
 449 }
 450
 451 static struct kvm *kvm_create_vm(unsigned long type)
 452 {
 453         int r, i;
 454         struct kvm *kvm = kvm_arch_alloc_vm();
 455
 456         if (!kvm)
 457                 return ERR_PTR(-ENOMEM);
 458
 459         r = kvm_arch_init_vm(kvm, type);
 460         if (r)
 461                 goto out_err_no_disable;
 462
 463         r = hardware_enable_all();
 464         if (r)
 465                 goto out_err_no_disable;
 466
 467 #ifdef CONFIG_HAVE_KVM_IRQFD
 468         INIT_HLIST_HEAD(&kvm->irq_ack_notifier_list);
 469 #endif
 470
 471         BUILD_BUG_ON(KVM_MEM_SLOTS_NUM > SHRT_MAX);
 472
 473         r = -ENOMEM;
 474         kvm->memslots = kzalloc(sizeof(struct kvm_memslots), GFP_KERNEL);
 475         if (!kvm->memslots)
 476                 goto out_err_no_srcu;
 477
 478         /*
 479          * Init kvm generation close to the maximum to easily test the
 480          * code of handling generation number wrap-around.
 481          */
 482         kvm->memslots->generation = -150;
 483
 484         kvm_init_memslots_id(kvm);
 485         if (init_srcu_struct(&kvm->srcu))
 486                 goto out_err_no_srcu;
 487         if (init_srcu_struct(&kvm->irq_srcu))
 488                 goto out_err_no_irq_srcu;
 489         for (i = 0; i < KVM_NR_BUSES; i++) {
 490                 kvm->buses[i] = kzalloc(sizeof(struct kvm_io_bus),
 491                                         GFP_KERNEL);
 492                 if (!kvm->buses[i])
 493                         goto out_err;
 494         }
 495
 496         spin_lock_init(&kvm->mmu_lock);
 497         kvm->mm = current->mm;
 498         atomic_inc(&kvm->mm->mm_count);
 499         kvm_eventfd_init(kvm);
 500         mutex_init(&kvm->lock);
 501         mutex_init(&kvm->irq_lock);
 502         mutex_init(&kvm->slots_lock);
 503         atomic_set(&kvm->users_count, 1);
 504         INIT_LIST_HEAD(&kvm->devices);
 505
 506         r = kvm_init_mmu_notifier(kvm);
 507         if (r)
 508                 goto out_err;
 509
 510         spin_lock(&kvm_lock);
 511         list_add(&kvm->vm_list, &vm_list);
 512         spin_unlock(&kvm_lock);
 513
 514         return kvm;
 515
 516 out_err:
 517         cleanup_srcu_struct(&kvm->irq_srcu);
 518 out_err_no_irq_srcu:
 519         cleanup_srcu_struct(&kvm->srcu);
 520 out_err_no_srcu:
 521         hardware_disable_all();
 522 out_err_no_disable:
 523         for (i = 0; i < KVM_NR_BUSES; i++)
 524                 kfree(kvm->buses[i]);
 525         kfree(kvm->memslots);
 526         kvm_arch_free_vm(kvm);
 527         return ERR_PTR(r);
 528 }
 529
 530 /*
 531  * Avoid using vmalloc for a small buffer.
 532  * Should not be used when the size is statically known.
 533  */
 534 void *kvm_kvzalloc(unsigned long size)
 535 {
 536         if (size > PAGE_SIZE)
 537                 return vzalloc(size);
 538         else
 539                 return kzalloc(size, GFP_KERNEL);
 540 }
 541
 542 static void kvm_destroy_dirty_bitmap(struct kvm_memory_slot *memslot)
 543 {
 544         if (!memslot->dirty_bitmap)
 545                 return;
 546
 547         kvfree(memslot->dirty_bitmap);
 548         memslot->dirty_bitmap = NULL;
 549 }
 550
 551 /*
 552  * Free any memory in @free but not in @dont.
 553  */
 554 static void kvm_free_physmem_slot(struct kvm *kvm, struct kvm_memory_slot *free,
 555                                   struct kvm_memory_slot *dont)
 556 {
 557         if (!dont || free->dirty_bitmap != dont->dirty_bitmap)
 558                 kvm_destroy_dirty_bitmap(free);
 559
 560         kvm_arch_free_memslot(kvm, free, dont);
 561
 562         free->npages = 0;
 563 }
 564
 565 static void kvm_free_physmem(struct kvm *kvm)
 566 {
 567         struct kvm_memslots *slots = kvm->memslots;
 568         struct kvm_memory_slot *memslot;
 569
 570         kvm_for_each_memslot(memslot, slots)
 571                 kvm_free_physmem_slot(kvm, memslot, NULL);
 572
 573         kfree(kvm->memslots);
 574 }
 575
 576 static void kvm_destroy_devices(struct kvm *kvm)
 577 {
 578         struct list_head *node, *tmp;
 579
 580         list_for_each_safe(node, tmp, &kvm->devices) {
 581                 struct kvm_device *dev =
 582                         list_entry(node, struct kvm_device, vm_node);
 583
 584                 list_del(node);
 585                 dev->ops->destroy(dev);
 586         }
 587 }
 588
 589 static void kvm_destroy_vm(struct kvm *kvm)
 590 {
 591         int i;
 592         struct mm_struct *mm = kvm->mm;
 593
 594         kvm_arch_sync_events(kvm);
 595         spin_lock(&kvm_lock);
 596         list_del(&kvm->vm_list);
 597         spin_unlock(&kvm_lock);
 598         kvm_free_irq_routing(kvm);
 599         for (i = 0; i < KVM_NR_BUSES; i++)
 600                 kvm_io_bus_destroy(kvm->buses[i]);
 601         kvm_coalesced_mmio_free(kvm);
 602 #if defined(CONFIG_MMU_NOTIFIER) && defined(KVM_ARCH_WANT_MMU_NOTIFIER)
 603         mmu_notifier_unregister(&kvm->mmu_notifier, kvm->mm);
 604 #else
 605         kvm_arch_flush_shadow_all(kvm);
 606 #endif
 607         kvm_arch_destroy_vm(kvm);
 608         kvm_destroy_devices(kvm);
 609         kvm_free_physmem(kvm);
 610         cleanup_srcu_struct(&kvm->irq_srcu);
 611         cleanup_srcu_struct(&kvm->srcu);
 612         kvm_arch_free_vm(kvm);
 613         hardware_disable_all();
 614         mmdrop(mm);
 615 }
 616
 617 void kvm_get_kvm(struct kvm *kvm)
 618 {
 619         atomic_inc(&kvm->users_count);
 620 }
 621 EXPORT_SYMBOL_GPL(kvm_get_kvm);
 622
 623 void kvm_put_kvm(struct kvm *kvm)
 624 {
 625         if (atomic_dec_and_test(&kvm->users_count))
 626                 kvm_destroy_vm(kvm);
 627 }
 628 EXPORT_SYMBOL_GPL(kvm_put_kvm);
 629
 630
 631 static int kvm_vm_release(struct inode *inode, struct file *filp)
 632 {
 633         struct kvm *kvm = filp->private_data;
 634
 635         kvm_irqfd_release(kvm);
 636
 637         kvm_put_kvm(kvm);
 638         return 0;
 639 }
 640
 641 /*
 642  * Allocation size is twice as large as the actual dirty bitmap size.
 643  * See x86's kvm_vm_ioctl_get_dirty_log() why this is needed.
 644  */
 645 static int kvm_create_dirty_bitmap(struct kvm_memory_slot *memslot)
 646 {
 647         unsigned long dirty_bytes = 2 * kvm_dirty_bitmap_bytes(memslot);
 648
 649         memslot->dirty_bitmap = kvm_kvzalloc(dirty_bytes);
 650         if (!memslot->dirty_bitmap)
 651                 return -ENOMEM;
 652
 653         return 0;
 654 }
 655
 656 /*
 657  * Insert memslot and re-sort memslots based on their GFN,
 658  * so binary search could be used to lookup GFN.
 659  * Sorting algorithm takes advantage of having initially
 660  * sorted array and known changed memslot position.
 661  */
 662 static void update_memslots(struct kvm_memslots *slots,
 663                             struct kvm_memory_slot *new)
 664 {
 665         int id = new->id;
 666         int i = slots->id_to_index[id];
 667         struct kvm_memory_slot *mslots = slots->memslots;
 668
 669         WARN_ON(mslots[i].id != id);
 670         if (!new->npages) {
 671                 WARN_ON(!mslots[i].npages);
 672                 new->base_gfn = 0;
 673                 new->flags = 0;
 674                 if (mslots[i].npages)
 675                         slots->used_slots--;
 676         } else {
 677                 if (!mslots[i].npages)
 678                         slots->used_slots++;
 679         }
 680
 681         while (i < KVM_MEM_SLOTS_NUM - 1 &&
 682                new->base_gfn <= mslots[i + 1].base_gfn) {
 683                 if (!mslots[i + 1].npages)
 684                         break;
 685                 mslots[i] = mslots[i + 1];
 686                 slots->id_to_index[mslots[i].id] = i;
 687                 i++;
 688         }
 689
 690         /*
 691          * The ">=" is needed when creating a slot with base_gfn == 0,
 692          * so that it moves before all those with base_gfn == npages == 0.
 693          *
 694          * On the other hand, if new->npages is zero, the above loop has
 695          * already left i pointing to the beginning of the empty part of
 696          * mslots, and the ">=" would move the hole backwards in this
 697          * case---which is wrong.  So skip the loop when deleting a slot.
 698          */
 699         if (new->npages) {
 700                 while (i > 0 &&
 701                        new->base_gfn >= mslots[i - 1].base_gfn) {
 702                         mslots[i] = mslots[i - 1];
 703                         slots->id_to_index[mslots[i].id] = i;
 704                         i--;
 705                 }
 706         } else
 707                 WARN_ON_ONCE(i != slots->used_slots);
 708
 709         mslots[i] = *new;
 710         slots->id_to_index[mslots[i].id] = i;
 711 }
 712
 713 static int check_memory_region_flags(struct kvm_userspace_memory_region *mem)
 714 {
 715         u32 valid_flags = KVM_MEM_LOG_DIRTY_PAGES;
 716
 717 #ifdef __KVM_HAVE_READONLY_MEM
 718         valid_flags |= KVM_MEM_READONLY;
 719 #endif
 720
 721         if (mem->flags & ~valid_flags)
 722                 return -EINVAL;
 723
 724         return 0;
 725 }
 726
 727 static struct kvm_memslots *install_new_memslots(struct kvm *kvm,
 728                 struct kvm_memslots *slots)
 729 {
 730         struct kvm_memslots *old_memslots = kvm->memslots;
 731
 732         /*
 733          * Set the low bit in the generation, which disables SPTE caching
 734          * until the end of synchronize_srcu_expedited.
 735          */
 736         WARN_ON(old_memslots->generation & 1);
 737         slots->generation = old_memslots->generation + 1;
 738
 739         rcu_assign_pointer(kvm->memslots, slots);
 740         synchronize_srcu_expedited(&kvm->srcu);
 741
 742         /*
 743          * Increment the new memslot generation a second time. This prevents
 744          * vm exits that race with memslot updates from caching a memslot
 745          * generation that will (potentially) be valid forever.
 746          */
 747         slots->generation++;
 748
 749         kvm_arch_memslots_updated(kvm);
 750
 751         return old_memslots;
 752 }
 753
 754 /*
 755  * Allocate some memory and give it an address in the guest physical address
 756  * space.
 757  *
 758  * Discontiguous memory is allowed, mostly for framebuffers.
 759  *
 760  * Must be called holding kvm->slots_lock for write.
 761  */
 762 int __kvm_set_memory_region(struct kvm *kvm,
 763                             struct kvm_userspace_memory_region *mem)
 764 {
 765         int r;
 766         gfn_t base_gfn;
 767         unsigned long npages;
 768         struct kvm_memory_slot *slot;
 769         struct kvm_memory_slot old, new;
 770         struct kvm_memslots *slots = NULL, *old_memslots;
 771         enum kvm_mr_change change;
 772
 773         r = check_memory_region_flags(mem);
 774         if (r)
 775                 goto out;
 776
 777         r = -EINVAL;
 778         /* General sanity checks */
 779         if (mem->memory_size & (PAGE_SIZE - 1))
 780                 goto out;
 781         if (mem->guest_phys_addr & (PAGE_SIZE - 1))
 782                 goto out;
 783         /* We can read the guest memory with __xxx_user() later on. */
 784         if ((mem->slot < KVM_USER_MEM_SLOTS) &&
 785             ((mem->userspace_addr & (PAGE_SIZE - 1)) ||
 786              !access_ok(VERIFY_WRITE,
 787                         (void __user *)(unsigned long)mem->userspace_addr,
 788                         mem->memory_size)))
 789                 goto out;
 790         if (mem->slot >= KVM_MEM_SLOTS_NUM)
 791                 goto out;
 792         if (mem->guest_phys_addr + mem->memory_size < mem->guest_phys_addr)
 793                 goto out;
 794
 795         slot = id_to_memslot(kvm->memslots, mem->slot);
 796         base_gfn = mem->guest_phys_addr >> PAGE_SHIFT;
 797         npages = mem->memory_size >> PAGE_SHIFT;
 798
 799         if (npages > KVM_MEM_MAX_NR_PAGES)
 800                 goto out;
 801
 802         if (!npages)
 803                 mem->flags &= ~KVM_MEM_LOG_DIRTY_PAGES;
 804
 805         new = old = *slot;
 806
 807         new.id = mem->slot;
 808         new.base_gfn = base_gfn;
 809         new.npages = npages;
 810         new.flags = mem->flags;
 811
 812         if (npages) {
 813                 if (!old.npages)
 814                         change = KVM_MR_CREATE;
 815                 else { /* Modify an existing slot. */
 816                         if ((mem->userspace_addr != old.userspace_addr) ||
 817                             (npages != old.npages) ||
 818                             ((new.flags ^ old.flags) & KVM_MEM_READONLY))
 819                                 goto out;
 820
 821                         if (base_gfn != old.base_gfn)
 822                                 change = KVM_MR_MOVE;
 823                         else if (new.flags != old.flags)
 824                                 change = KVM_MR_FLAGS_ONLY;
 825                         else { /* Nothing to change. */
 826                                 r = 0;
 827                                 goto out;
 828                         }
 829                 }
 830         } else if (old.npages) {
 831                 change = KVM_MR_DELETE;
 832         } else /* Modify a non-existent slot: disallowed. */
 833                 goto out;
 834
 835         if ((change == KVM_MR_CREATE) || (change == KVM_MR_MOVE)) {
 836                 /* Check for overlaps */
 837                 r = -EEXIST;
 838                 kvm_for_each_memslot(slot, kvm->memslots) {
 839                         if ((slot->id >= KVM_USER_MEM_SLOTS) ||
 840                             (slot->id == mem->slot))
 841                                 continue;
 842                         if (!((base_gfn + npages <= slot->base_gfn) ||
 843                               (base_gfn >= slot->base_gfn + slot->npages)))
 844                                 goto out;
 845                 }
 846         }
 847
 848         /* Free page dirty bitmap if unneeded */
 849         if (!(new.flags & KVM_MEM_LOG_DIRTY_PAGES))
 850                 new.dirty_bitmap = NULL;
 851
 852         r = -ENOMEM;
 853         if (change == KVM_MR_CREATE) {
 854                 new.userspace_addr = mem->userspace_addr;
 855
 856                 if (kvm_arch_create_memslot(kvm, &new, npages))
 857                         goto out_free;
 858         }
 859
 860         /* Allocate page dirty bitmap if needed */
 861         if ((new.flags & KVM_MEM_LOG_DIRTY_PAGES) && !new.dirty_bitmap) {
 862                 if (kvm_create_dirty_bitmap(&new) < 0)
 863                         goto out_free;
 864         }
 865
 866         slots = kmemdup(kvm->memslots, sizeof(struct kvm_memslots),
 867                         GFP_KERNEL);
 868         if (!slots)
 869                 goto out_free;
 870
 871         if ((change == KVM_MR_DELETE) || (change == KVM_MR_MOVE)) {
 872                 slot = id_to_memslot(slots, mem->slot);
 873                 slot->flags |= KVM_MEMSLOT_INVALID;
 874
 875                 old_memslots = install_new_memslots(kvm, slots);
 876
 877                 /* slot was deleted or moved, clear iommu mapping */
 878                 kvm_iommu_unmap_pages(kvm, &old);
 879                 /* From this point no new shadow pages pointing to a deleted,
 880                  * or moved, memslot will be created.
 881                  *
 882                  * validation of sp->gfn happens in:
 883                  *      - gfn_to_hva (kvm_read_guest, gfn_to_pfn)
 884                  *      - kvm_is_visible_gfn (mmu_check_roots)
 885                  */
 886                 kvm_arch_flush_shadow_memslot(kvm, slot);
 887
 888                 /*
 889                  * We can re-use the old_memslots from above, the only difference
 890                  * from the currently installed memslots is the invalid flag.  This
 891                  * will get overwritten by update_memslots anyway.
 892                  */
 893                 slots = old_memslots;
 894         }
 895
 896         r = kvm_arch_prepare_memory_region(kvm, &new, mem, change);
 897         if (r)
 898                 goto out_slots;
 899
 900         /* actual memory is freed via old in kvm_free_physmem_slot below */
 901         if (change == KVM_MR_DELETE) {
 902                 new.dirty_bitmap = NULL;
 903                 memset(&new.arch, 0, sizeof(new.arch));
 904         }
 905
 906         update_memslots(slots, &new);
 907         old_memslots = install_new_memslots(kvm, slots);
 908
 909         kvm_arch_commit_memory_region(kvm, mem, &old, change);
 910
 911         kvm_free_physmem_slot(kvm, &old, &new);
 912         kfree(old_memslots);
 913
 914         /*
 915          * IOMMU mapping:  New slots need to be mapped.  Old slots need to be
 916          * un-mapped and re-mapped if their base changes.  Since base change
 917          * unmapping is handled above with slot deletion, mapping alone is
 918          * needed here.  Anything else the iommu might care about for existing
 919          * slots (size changes, userspace addr changes and read-only flag
 920          * changes) is disallowed above, so any other attribute changes getting
 921          * here can be skipped.
 922          */
 923         if ((change == KVM_MR_CREATE) || (change == KVM_MR_MOVE)) {
 924                 r = kvm_iommu_map_pages(kvm, &new);
 925                 return r;
 926         }
 927
 928         return 0;
 929
 930 out_slots:
 931         kfree(slots);
 932 out_free:
 933         kvm_free_physmem_slot(kvm, &new, &old);
 934 out:
 935         return r;
 936 }
 937 EXPORT_SYMBOL_GPL(__kvm_set_memory_region);
 938
 939 int kvm_set_memory_region(struct kvm *kvm,
 940                           struct kvm_userspace_memory_region *mem)
 941 {
 942         int r;
 943
 944         mutex_lock(&kvm->slots_lock);
 945         r = __kvm_set_memory_region(kvm, mem);
 946         mutex_unlock(&kvm->slots_lock);
 947         return r;
 948 }
 949 EXPORT_SYMBOL_GPL(kvm_set_memory_region);
 950
 951 static int kvm_vm_ioctl_set_memory_region(struct kvm *kvm,
 952                                           struct kvm_userspace_memory_region *mem)
 953 {
 954         if (mem->slot >= KVM_USER_MEM_SLOTS)
 955                 return -EINVAL;
 956         return kvm_set_memory_region(kvm, mem);
 957 }
 958
 959 int kvm_get_dirty_log(struct kvm *kvm,
 960                         struct kvm_dirty_log *log, int *is_dirty)
 961 {
 962         struct kvm_memory_slot *memslot;
 963         int r, i;
 964         unsigned long n;
 965         unsigned long any = 0;
 966
 967         r = -EINVAL;
 968         if (log->slot >= KVM_USER_MEM_SLOTS)
 969                 goto out;
 970
 971         memslot = id_to_memslot(kvm->memslots, log->slot);
 972         r = -ENOENT;
 973         if (!memslot->dirty_bitmap)
 974                 goto out;
 975
 976         n = kvm_dirty_bitmap_bytes(memslot);
 977
 978         for (i = 0; !any && i < n/sizeof(long); ++i)
 979                 any = memslot->dirty_bitmap[i];
 980
 981         r = -EFAULT;
 982         if (copy_to_user(log->dirty_bitmap, memslot->dirty_bitmap, n))
 983                 goto out;
 984
 985         if (any)
 986                 *is_dirty = 1;
 987
 988         r = 0;
 989 out:
 990         return r;
 991 }
 992 EXPORT_SYMBOL_GPL(kvm_get_dirty_log);
 993
 994 #ifdef CONFIG_KVM_GENERIC_DIRTYLOG_READ_PROTECT
 995 /**
 996  * kvm_get_dirty_log_protect - get a snapshot of dirty pages, and if any pages
 997  *      are dirty write protect them for next write.
 998  * @kvm:        pointer to kvm instance
 999  * @log:        slot id and address to which we copy the log
1000  * @is_dirty:   flag set if any page is dirty
1001  *
1002  * We need to keep it in mind that VCPU threads can write to the bitmap
1003  * concurrently. So, to avoid losing track of dirty pages we keep the
1004  * following order:
1005  *
1006  *    1. Take a snapshot of the bit and clear it if needed.
1007  *    2. Write protect the corresponding page.
1008  *    3. Copy the snapshot to the userspace.
1009  *    4. Upon return caller flushes TLB's if needed.
1010  *
1011  * Between 2 and 4, the guest may write to the page using the remaining TLB
1012  * entry.  This is not a problem because the page is reported dirty using
1013  * the snapshot taken before and step 4 ensures that writes done after
1014  * exiting to userspace will be logged for the next call.
1015  *
1016  */
1017 int kvm_get_dirty_log_protect(struct kvm *kvm,
1018                         struct kvm_dirty_log *log, bool *is_dirty)
1019 {
1020         struct kvm_memory_slot *memslot;
1021         int r, i;
1022         unsigned long n;
1023         unsigned long *dirty_bitmap;
1024         unsigned long *dirty_bitmap_buffer;
1025
1026         r = -EINVAL;
1027         if (log->slot >= KVM_USER_MEM_SLOTS)
1028                 goto out;
1029
1030         memslot = id_to_memslot(kvm->memslots, log->slot);
1031
1032         dirty_bitmap = memslot->dirty_bitmap;
1033         r = -ENOENT;
1034         if (!dirty_bitmap)
1035                 goto out;
1036
1037         n = kvm_dirty_bitmap_bytes(memslot);
1038
1039         dirty_bitmap_buffer = dirty_bitmap + n / sizeof(long);
1040         memset(dirty_bitmap_buffer, 0, n);
1041
1042         spin_lock(&kvm->mmu_lock);
1043         *is_dirty = false;
1044         for (i = 0; i < n / sizeof(long); i++) {
1045                 unsigned long mask;
1046                 gfn_t offset;
1047
1048                 if (!dirty_bitmap[i])
1049                         continue;
1050
1051                 *is_dirty = true;
1052
1053                 mask = xchg(&dirty_bitmap[i], 0);
1054                 dirty_bitmap_buffer[i] = mask;
1055
1056                 if (mask) {
1057                         offset = i * BITS_PER_LONG;
1058                         kvm_arch_mmu_enable_log_dirty_pt_masked(kvm, memslot,
1059                                                                 offset, mask);
1060                 }
1061         }
1062
1063         spin_unlock(&kvm->mmu_lock);
1064
1065         r = -EFAULT;
1066         if (copy_to_user(log->dirty_bitmap, dirty_bitmap_buffer, n))
1067                 goto out;
1068
1069         r = 0;
1070 out:
1071         return r;
1072 }
1073 EXPORT_SYMBOL_GPL(kvm_get_dirty_log_protect);
1074 #endif
1075
1076 bool kvm_largepages_enabled(void)
1077 {
1078         return largepages_enabled;
1079 }
1080
1081 void kvm_disable_largepages(void)
1082 {
1083         largepages_enabled = false;
1084 }
1085 EXPORT_SYMBOL_GPL(kvm_disable_largepages);
1086
1087 struct kvm_memory_slot *gfn_to_memslot(struct kvm *kvm, gfn_t gfn)
1088 {
1089         return __gfn_to_memslot(kvm_memslots(kvm), gfn);
1090 }
1091 EXPORT_SYMBOL_GPL(gfn_to_memslot);
1092
1093 int kvm_is_visible_gfn(struct kvm *kvm, gfn_t gfn)
1094 {
1095         struct kvm_memory_slot *memslot = gfn_to_memslot(kvm, gfn);
1096
1097         if (!memslot || memslot->id >= KVM_USER_MEM_SLOTS ||
1098               memslot->flags & KVM_MEMSLOT_INVALID)
1099                 return 0;
1100
1101         return 1;
1102 }
1103 EXPORT_SYMBOL_GPL(kvm_is_visible_gfn);
1104
1105 unsigned long kvm_host_page_size(struct kvm *kvm, gfn_t gfn)
1106 {
1107         struct vm_area_struct *vma;
1108         unsigned long addr, size;
1109
1110         size = PAGE_SIZE;
1111
1112         addr = gfn_to_hva(kvm, gfn);
1113         if (kvm_is_error_hva(addr))
1114                 return PAGE_SIZE;
1115
1116         down_read(&current->mm->mmap_sem);
1117         vma = find_vma(current->mm, addr);
1118         if (!vma)
1119                 goto out;
1120
1121         size = vma_kernel_pagesize(vma);
1122
1123 out:
1124         up_read(&current->mm->mmap_sem);
1125
1126         return size;
1127 }
1128
1129 static bool memslot_is_readonly(struct kvm_memory_slot *slot)
1130 {
1131         return slot->flags & KVM_MEM_READONLY;
1132 }
1133
1134 static unsigned long __gfn_to_hva_many(struct kvm_memory_slot *slot, gfn_t gfn,
1135                                        gfn_t *nr_pages, bool write)
1136 {
1137         if (!slot || slot->flags & KVM_MEMSLOT_INVALID)
1138                 return KVM_HVA_ERR_BAD;
1139
1140         if (memslot_is_readonly(slot) && write)
1141                 return KVM_HVA_ERR_RO_BAD;
1142
1143         if (nr_pages)
1144                 *nr_pages = slot->npages - (gfn - slot->base_gfn);
1145
1146         return __gfn_to_hva_memslot(slot, gfn);
1147 }
1148
1149 static unsigned long gfn_to_hva_many(struct kvm_memory_slot *slot, gfn_t gfn,
1150                                      gfn_t *nr_pages)
1151 {
1152         return __gfn_to_hva_many(slot, gfn, nr_pages, true);
1153 }
1154
1155 unsigned long gfn_to_hva_memslot(struct kvm_memory_slot *slot,
1156                                         gfn_t gfn)
1157 {
1158         return gfn_to_hva_many(slot, gfn, NULL);
1159 }
1160 EXPORT_SYMBOL_GPL(gfn_to_hva_memslot);
1161
1162 unsigned long gfn_to_hva(struct kvm *kvm, gfn_t gfn)
1163 {
1164         return gfn_to_hva_many(gfn_to_memslot(kvm, gfn), gfn, NULL);
1165 }
1166 EXPORT_SYMBOL_GPL(gfn_to_hva);
1167
1168 /*
1169  * If writable is set to false, the hva returned by this function is only
1170  * allowed to be read.
1171  */
1172 unsigned long gfn_to_hva_memslot_prot(struct kvm_memory_slot *slot,
1173                                       gfn_t gfn, bool *writable)
1174 {
1175         unsigned long hva = __gfn_to_hva_many(slot, gfn, NULL, false);
1176
1177         if (!kvm_is_error_hva(hva) && writable)
1178                 *writable = !memslot_is_readonly(slot);
1179
1180         return hva;
1181 }
1182
1183 unsigned long gfn_to_hva_prot(struct kvm *kvm, gfn_t gfn, bool *writable)
1184 {
1185         struct kvm_memory_slot *slot = gfn_to_memslot(kvm, gfn);
1186
1187         return gfn_to_hva_memslot_prot(slot, gfn, writable);
1188 }
1189
1190 static int get_user_page_nowait(struct task_struct *tsk, struct mm_struct *mm,
1191         unsigned long start, int write, struct page **page)
1192 {
1193         int flags = FOLL_TOUCH | FOLL_NOWAIT | FOLL_HWPOISON | FOLL_GET;
1194
1195         if (write)
1196                 flags |= FOLL_WRITE;
1197
1198         return __get_user_pages(tsk, mm, start, 1, flags, page, NULL, NULL);
1199 }
1200
1201 static inline int check_user_page_hwpoison(unsigned long addr)
1202 {
1203         int rc, flags = FOLL_TOUCH | FOLL_HWPOISON | FOLL_WRITE;
1204
1205         rc = __get_user_pages(current, current->mm, addr, 1,
1206                               flags, NULL, NULL, NULL);
1207         return rc == -EHWPOISON;
1208 }
1209
1210 /*
1211  * The atomic path to get the writable pfn which will be stored in @pfn,
1212  * true indicates success, otherwise false is returned.
1213  */
1214 static bool hva_to_pfn_fast(unsigned long addr, bool atomic, bool *async,
1215                             bool write_fault, bool *writable, pfn_t *pfn)
1216 {
1217         struct page *page[1];
1218         int npages;
1219
1220         if (!(async || atomic))
1221                 return false;
1222
1223         /*
1224          * Fast pin a writable pfn only if it is a write fault request
1225          * or the caller allows to map a writable pfn for a read fault
1226          * request.
1227          */
1228         if (!(write_fault || writable))
1229                 return false;
1230
1231         npages = __get_user_pages_fast(addr, 1, 1, page);
1232         if (npages == 1) {
1233                 *pfn = page_to_pfn(page[0]);
1234
1235                 if (writable)
1236                         *writable = true;
1237                 return true;
1238         }
1239
1240         return false;
1241 }
1242
1243 /*
1244  * The slow path to get the pfn of the specified host virtual address,
1245  * 1 indicates success, -errno is returned if error is detected.
1246  */
1247 static int hva_to_pfn_slow(unsigned long addr, bool *async, bool write_fault,
1248                            bool *writable, pfn_t *pfn)
1249 {
1250         struct page *page[1];
1251         int npages = 0;
1252
1253         might_sleep();
1254
1255         if (writable)
1256                 *writable = write_fault;
1257
1258         if (async) {
1259                 down_read(&current->mm->mmap_sem);
1260                 npages = get_user_page_nowait(current, current->mm,
1261                                               addr, write_fault, page);
1262                 up_read(&current->mm->mmap_sem);
1263         } else
1264                 npages = __get_user_pages_unlocked(current, current->mm, addr, 1,
1265                                                    write_fault, 0, page,
1266                                                    FOLL_TOUCH|FOLL_HWPOISON);
1267         if (npages != 1)
1268                 return npages;
1269
1270         /* map read fault as writable if possible */
1271         if (unlikely(!write_fault) && writable) {
1272                 struct page *wpage[1];
1273
1274                 npages = __get_user_pages_fast(addr, 1, 1, wpage);
1275                 if (npages == 1) {
1276                         *writable = true;
1277                         put_page(page[0]);
1278                         page[0] = wpage[0];
1279                 }
1280
1281                 npages = 1;
1282         }
1283         *pfn = page_to_pfn(page[0]);
1284         return npages;
1285 }
1286
1287 static bool vma_is_valid(struct vm_area_struct *vma, bool write_fault)
1288 {
1289         if (unlikely(!(vma->vm_flags & VM_READ)))
1290                 return false;
1291
1292         if (write_fault && (unlikely(!(vma->vm_flags & VM_WRITE))))
1293                 return false;
1294
1295         return true;
1296 }
1297
1298 /*
1299  * Pin guest page in memory and return its pfn.
1300  * @addr: host virtual address which maps memory to the guest
1301  * @atomic: whether this function can sleep
1302  * @async: whether this function need to wait IO complete if the
1303  *         host page is not in the memory
1304  * @write_fault: whether we should get a writable host page
1305  * @writable: whether it allows to map a writable host page for !@write_fault
1306  *
1307  * The function will map a writable host page for these two cases:
1308  * 1): @write_fault = true
1309  * 2): @write_fault = false && @writable, @writable will tell the caller
1310  *     whether the mapping is writable.
1311  */
1312 static pfn_t hva_to_pfn(unsigned long addr, bool atomic, bool *async,
1313                         bool write_fault, bool *writable)
1314 {
1315         struct vm_area_struct *vma;
1316         pfn_t pfn = 0;
1317         int npages;
1318
1319         /* we can do it either atomically or asynchronously, not both */
1320         BUG_ON(atomic && async);
1321
1322         if (hva_to_pfn_fast(addr, atomic, async, write_fault, writable, &pfn))
1323                 return pfn;
1324
1325         if (atomic)
1326                 return KVM_PFN_ERR_FAULT;
1327
1328         npages = hva_to_pfn_slow(addr, async, write_fault, writable, &pfn);
1329         if (npages == 1)
1330                 return pfn;
1331
1332         down_read(&current->mm->mmap_sem);
1333         if (npages == -EHWPOISON ||
1334               (!async && check_user_page_hwpoison(addr))) {
1335                 pfn = KVM_PFN_ERR_HWPOISON;
1336                 goto exit;
1337         }
1338
1339         vma = find_vma_intersection(current->mm, addr, addr + 1);
1340
1341         if (vma == NULL)
1342                 pfn = KVM_PFN_ERR_FAULT;
1343         else if ((vma->vm_flags & VM_PFNMAP)) {
1344                 pfn = ((addr - vma->vm_start) >> PAGE_SHIFT) +
1345                         vma->vm_pgoff;
1346                 BUG_ON(!kvm_is_reserved_pfn(pfn));
1347         } else {
1348                 if (async && vma_is_valid(vma, write_fault))
1349                         *async = true;
1350                 pfn = KVM_PFN_ERR_FAULT;
1351         }
1352 exit:
1353         up_read(&current->mm->mmap_sem);
1354         return pfn;
1355 }
1356
1357 static pfn_t
1358 __gfn_to_pfn_memslot(struct kvm_memory_slot *slot, gfn_t gfn, bool atomic,
1359                      bool *async, bool write_fault, bool *writable)
1360 {
1361         unsigned long addr = __gfn_to_hva_many(slot, gfn, NULL, write_fault);
1362
1363         if (addr == KVM_HVA_ERR_RO_BAD)
1364                 return KVM_PFN_ERR_RO_FAULT;
1365
1366         if (kvm_is_error_hva(addr))
1367                 return KVM_PFN_NOSLOT;
1368
1369         /* Do not map writable pfn in the readonly memslot. */
1370         if (writable && memslot_is_readonly(slot)) {
1371                 *writable = false;
1372                 writable = NULL;
1373         }
1374
1375         return hva_to_pfn(addr, atomic, async, write_fault,
1376                           writable);
1377 }
1378
1379 static pfn_t __gfn_to_pfn(struct kvm *kvm, gfn_t gfn, bool atomic, bool *async,
1380                           bool write_fault, bool *writable)
1381 {
1382         struct kvm_memory_slot *slot;
1383
1384         if (async)
1385                 *async = false;
1386
1387         slot = gfn_to_memslot(kvm, gfn);
1388
1389         return __gfn_to_pfn_memslot(slot, gfn, atomic, async, write_fault,
1390                                     writable);
1391 }
1392
1393 pfn_t gfn_to_pfn_atomic(struct kvm *kvm, gfn_t gfn)
1394 {
1395         return __gfn_to_pfn(kvm, gfn, true, NULL, true, NULL);
1396 }
1397 EXPORT_SYMBOL_GPL(gfn_to_pfn_atomic);
1398
1399 pfn_t gfn_to_pfn_async(struct kvm *kvm, gfn_t gfn, bool *async,
1400                        bool write_fault, bool *writable)
1401 {
1402         return __gfn_to_pfn(kvm, gfn, false, async, write_fault, writable);
1403 }
1404 EXPORT_SYMBOL_GPL(gfn_to_pfn_async);
1405
1406 pfn_t gfn_to_pfn(struct kvm *kvm, gfn_t gfn)
1407 {
1408         return __gfn_to_pfn(kvm, gfn, false, NULL, true, NULL);
1409 }
1410 EXPORT_SYMBOL_GPL(gfn_to_pfn);
1411
1412 pfn_t gfn_to_pfn_prot(struct kvm *kvm, gfn_t gfn, bool write_fault,
1413                       bool *writable)
1414 {
1415         return __gfn_to_pfn(kvm, gfn, false, NULL, write_fault, writable);
1416 }
1417 EXPORT_SYMBOL_GPL(gfn_to_pfn_prot);
1418
1419 pfn_t gfn_to_pfn_memslot(struct kvm_memory_slot *slot, gfn_t gfn)
1420 {
1421         return __gfn_to_pfn_memslot(slot, gfn, false, NULL, true, NULL);
1422 }
1423
1424 pfn_t gfn_to_pfn_memslot_atomic(struct kvm_memory_slot *slot, gfn_t gfn)
1425 {
1426         return __gfn_to_pfn_memslot(slot, gfn, true, NULL, true, NULL);
1427 }
1428 EXPORT_SYMBOL_GPL(gfn_to_pfn_memslot_atomic);
1429
1430 int gfn_to_page_many_atomic(struct kvm *kvm, gfn_t gfn, struct page **pages,
1431                                                                   int nr_pages)
1432 {
1433         unsigned long addr;
1434         gfn_t entry;
1435
1436         addr = gfn_to_hva_many(gfn_to_memslot(kvm, gfn), gfn, &entry);
1437         if (kvm_is_error_hva(addr))
1438                 return -1;
1439
1440         if (entry < nr_pages)
1441                 return 0;
1442
1443         return __get_user_pages_fast(addr, nr_pages, 1, pages);
1444 }
1445 EXPORT_SYMBOL_GPL(gfn_to_page_many_atomic);
1446
1447 static struct page *kvm_pfn_to_page(pfn_t pfn)
1448 {
1449         if (is_error_noslot_pfn(pfn))
1450                 return KVM_ERR_PTR_BAD_PAGE;
1451
1452         if (kvm_is_reserved_pfn(pfn)) {
1453                 WARN_ON(1);
1454                 return KVM_ERR_PTR_BAD_PAGE;
1455         }
1456
1457         return pfn_to_page(pfn);
1458 }
1459
1460 struct page *gfn_to_page(struct kvm *kvm, gfn_t gfn)
1461 {
1462         pfn_t pfn;
1463
1464         pfn = gfn_to_pfn(kvm, gfn);
1465
1466         return kvm_pfn_to_page(pfn);
1467 }
1468 EXPORT_SYMBOL_GPL(gfn_to_page);
1469
1470 void kvm_release_page_clean(struct page *page)
1471 {
1472         WARN_ON(is_error_page(page));
1473
1474         kvm_release_pfn_clean(page_to_pfn(page));
1475 }
1476 EXPORT_SYMBOL_GPL(kvm_release_page_clean);
1477
1478 void kvm_release_pfn_clean(pfn_t pfn)
1479 {
1480         if (!is_error_noslot_pfn(pfn) && !kvm_is_reserved_pfn(pfn))
1481                 put_page(pfn_to_page(pfn));
1482 }
1483 EXPORT_SYMBOL_GPL(kvm_release_pfn_clean);
1484
1485 void kvm_release_page_dirty(struct page *page)
1486 {
1487         WARN_ON(is_error_page(page));
1488
1489         kvm_release_pfn_dirty(page_to_pfn(page));
1490 }
1491 EXPORT_SYMBOL_GPL(kvm_release_page_dirty);
1492
1493 static void kvm_release_pfn_dirty(pfn_t pfn)
1494 {
1495         kvm_set_pfn_dirty(pfn);
1496         kvm_release_pfn_clean(pfn);
1497 }
1498
1499 void kvm_set_pfn_dirty(pfn_t pfn)
1500 {
1501         if (!kvm_is_reserved_pfn(pfn)) {
1502                 struct page *page = pfn_to_page(pfn);
1503
1504                 if (!PageReserved(page))
1505                         SetPageDirty(page);
1506         }
1507 }
1508 EXPORT_SYMBOL_GPL(kvm_set_pfn_dirty);
1509
1510 void kvm_set_pfn_accessed(pfn_t pfn)
1511 {
1512         if (!kvm_is_reserved_pfn(pfn))
1513                 mark_page_accessed(pfn_to_page(pfn));
1514 }
1515 EXPORT_SYMBOL_GPL(kvm_set_pfn_accessed);
1516
1517 void kvm_get_pfn(pfn_t pfn)
1518 {
1519         if (!kvm_is_reserved_pfn(pfn))
1520                 get_page(pfn_to_page(pfn));
1521 }
1522 EXPORT_SYMBOL_GPL(kvm_get_pfn);
1523
1524 static int next_segment(unsigned long len, int offset)
1525 {
1526         if (len > PAGE_SIZE - offset)
1527                 return PAGE_SIZE - offset;
1528         else
1529                 return len;
1530 }
1531
1532 int kvm_read_guest_page(struct kvm *kvm, gfn_t gfn, void *data, int offset,
1533                         int len)
1534 {
1535         int r;
1536         unsigned long addr;
1537
1538         addr = gfn_to_hva_prot(kvm, gfn, NULL);
1539         if (kvm_is_error_hva(addr))
1540                 return -EFAULT;
1541         r = __copy_from_user(data, (void __user *)addr + offset, len);
1542         if (r)
1543                 return -EFAULT;
1544         return 0;
1545 }
1546 EXPORT_SYMBOL_GPL(kvm_read_guest_page);
1547
1548 int kvm_read_guest(struct kvm *kvm, gpa_t gpa, void *data, unsigned long len)
1549 {
1550         gfn_t gfn = gpa >> PAGE_SHIFT;
1551         int seg;
1552         int offset = offset_in_page(gpa);
1553         int ret;
1554
1555         while ((seg = next_segment(len, offset)) != 0) {
1556                 ret = kvm_read_guest_page(kvm, gfn, data, offset, seg);
1557                 if (ret < 0)
1558                         return ret;
1559                 offset = 0;
1560                 len -= seg;
1561                 data += seg;
1562                 ++gfn;
1563         }
1564         return 0;
1565 }
1566 EXPORT_SYMBOL_GPL(kvm_read_guest);
1567
1568 int kvm_read_guest_atomic(struct kvm *kvm, gpa_t gpa, void *data,
1569                           unsigned long len)
1570 {
1571         int r;
1572         unsigned long addr;
1573         gfn_t gfn = gpa >> PAGE_SHIFT;
1574         int offset = offset_in_page(gpa);
1575
1576         addr = gfn_to_hva_prot(kvm, gfn, NULL);
1577         if (kvm_is_error_hva(addr))
1578                 return -EFAULT;
1579         pagefault_disable();
1580         r = __copy_from_user_inatomic(data, (void __user *)addr + offset, len);
1581         pagefault_enable();
1582         if (r)
1583                 return -EFAULT;
1584         return 0;
1585 }
1586 EXPORT_SYMBOL(kvm_read_guest_atomic);
1587
1588 int kvm_write_guest_page(struct kvm *kvm, gfn_t gfn, const void *data,
1589                          int offset, int len)
1590 {
1591         int r;
1592         unsigned long addr;
1593
1594         addr = gfn_to_hva(kvm, gfn);
1595         if (kvm_is_error_hva(addr))
1596                 return -EFAULT;
1597         r = __copy_to_user((void __user *)addr + offset, data, len);
1598         if (r)
1599                 return -EFAULT;
1600         mark_page_dirty(kvm, gfn);
1601         return 0;
1602 }
1603 EXPORT_SYMBOL_GPL(kvm_write_guest_page);
1604
1605 int kvm_write_guest(struct kvm *kvm, gpa_t gpa, const void *data,
1606                     unsigned long len)
1607 {
1608         gfn_t gfn = gpa >> PAGE_SHIFT;
1609         int seg;
1610         int offset = offset_in_page(gpa);
1611         int ret;
1612
1613         while ((seg = next_segment(len, offset)) != 0) {
1614                 ret = kvm_write_guest_page(kvm, gfn, data, offset, seg);
1615                 if (ret < 0)
1616                         return ret;
1617                 offset = 0;
1618                 len -= seg;
1619                 data += seg;
1620                 ++gfn;
1621         }
1622         return 0;
1623 }
1624 EXPORT_SYMBOL_GPL(kvm_write_guest);
1625
1626 int kvm_gfn_to_hva_cache_init(struct kvm *kvm, struct gfn_to_hva_cache *ghc,
1627                               gpa_t gpa, unsigned long len)
1628 {
1629         struct kvm_memslots *slots = kvm_memslots(kvm);
1630         int offset = offset_in_page(gpa);
1631         gfn_t start_gfn = gpa >> PAGE_SHIFT;
1632         gfn_t end_gfn = (gpa + len - 1) >> PAGE_SHIFT;
1633         gfn_t nr_pages_needed = end_gfn - start_gfn + 1;
1634         gfn_t nr_pages_avail;
1635
1636         ghc->gpa = gpa;
1637         ghc->generation = slots->generation;
1638         ghc->len = len;
1639         ghc->memslot = gfn_to_memslot(kvm, start_gfn);
1640         ghc->hva = gfn_to_hva_many(ghc->memslot, start_gfn, &nr_pages_avail);
1641         if (!kvm_is_error_hva(ghc->hva) && nr_pages_avail >= nr_pages_needed) {
1642                 ghc->hva += offset;
1643         } else {
1644                 /*
1645                  * If the requested region crosses two memslots, we still
1646                  * verify that the entire region is valid here.
1647                  */
1648                 while (start_gfn <= end_gfn) {
1649                         ghc->memslot = gfn_to_memslot(kvm, start_gfn);
1650                         ghc->hva = gfn_to_hva_many(ghc->memslot, start_gfn,
1651                                                    &nr_pages_avail);
1652                         if (kvm_is_error_hva(ghc->hva))
1653                                 return -EFAULT;
1654                         start_gfn += nr_pages_avail;
1655                 }
1656                 /* Use the slow path for cross page reads and writes. */
1657                 ghc->memslot = NULL;
1658         }
1659         return 0;
1660 }
1661 EXPORT_SYMBOL_GPL(kvm_gfn_to_hva_cache_init);
1662
1663 int kvm_write_guest_cached(struct kvm *kvm, struct gfn_to_hva_cache *ghc,
1664                            void *data, unsigned long len)
1665 {
1666         struct kvm_memslots *slots = kvm_memslots(kvm);
1667         int r;
1668
1669         BUG_ON(len > ghc->len);
1670
1671         if (slots->generation != ghc->generation)
1672                 kvm_gfn_to_hva_cache_init(kvm, ghc, ghc->gpa, ghc->len);
1673
1674         if (unlikely(!ghc->memslot))
1675                 return kvm_write_guest(kvm, ghc->gpa, data, len);
1676
1677         if (kvm_is_error_hva(ghc->hva))
1678                 return -EFAULT;
1679
1680         r = __copy_to_user((void __user *)ghc->hva, data, len);
1681         if (r)
1682                 return -EFAULT;
1683         mark_page_dirty_in_slot(kvm, ghc->memslot, ghc->gpa >> PAGE_SHIFT);
1684
1685         return 0;
1686 }
1687 EXPORT_SYMBOL_GPL(kvm_write_guest_cached);
1688
1689 int kvm_read_guest_cached(struct kvm *kvm, struct gfn_to_hva_cache *ghc,
1690                            void *data, unsigned long len)
1691 {
1692         struct kvm_memslots *slots = kvm_memslots(kvm);
1693         int r;
1694
1695         BUG_ON(len > ghc->len);
1696
1697         if (slots->generation != ghc->generation)
1698                 kvm_gfn_to_hva_cache_init(kvm, ghc, ghc->gpa, ghc->len);
1699
1700         if (unlikely(!ghc->memslot))
1701                 return kvm_read_guest(kvm, ghc->gpa, data, len);
1702
1703         if (kvm_is_error_hva(ghc->hva))
1704                 return -EFAULT;
1705
1706         r = __copy_from_user(data, (void __user *)ghc->hva, len);
1707         if (r)
1708                 return -EFAULT;
1709
1710         return 0;
1711 }
1712 EXPORT_SYMBOL_GPL(kvm_read_guest_cached);
1713
1714 int kvm_clear_guest_page(struct kvm *kvm, gfn_t gfn, int offset, int len)
1715 {
1716         const void *zero_page = (const void *) __va(page_to_phys(ZERO_PAGE(0)));
1717
1718         return kvm_write_guest_page(kvm, gfn, zero_page, offset, len);
1719 }
1720 EXPORT_SYMBOL_GPL(kvm_clear_guest_page);
1721
1722 int kvm_clear_guest(struct kvm *kvm, gpa_t gpa, unsigned long len)
1723 {
1724         gfn_t gfn = gpa >> PAGE_SHIFT;
1725         int seg;
1726         int offset = offset_in_page(gpa);
1727         int ret;
1728
1729         while ((seg = next_segment(len, offset)) != 0) {
1730                 ret = kvm_clear_guest_page(kvm, gfn, offset, seg);
1731                 if (ret < 0)
1732                         return ret;
1733                 offset = 0;
1734                 len -= seg;
1735                 ++gfn;
1736         }
1737         return 0;
1738 }
1739 EXPORT_SYMBOL_GPL(kvm_clear_guest);
1740
1741 static void mark_page_dirty_in_slot(struct kvm *kvm,
1742                                     struct kvm_memory_slot *memslot,
1743                                     gfn_t gfn)
1744 {
1745         if (memslot && memslot->dirty_bitmap) {
1746                 unsigned long rel_gfn = gfn - memslot->base_gfn;
1747
1748                 set_bit_le(rel_gfn, memslot->dirty_bitmap);
1749         }
1750 }
1751
1752 void mark_page_dirty(struct kvm *kvm, gfn_t gfn)
1753 {
1754         struct kvm_memory_slot *memslot;
1755
1756         memslot = gfn_to_memslot(kvm, gfn);
1757         mark_page_dirty_in_slot(kvm, memslot, gfn);
1758 }
1759 EXPORT_SYMBOL_GPL(mark_page_dirty);
1760
1761 static int kvm_vcpu_check_block(struct kvm_vcpu *vcpu)
1762 {
1763         if (kvm_arch_vcpu_runnable(vcpu)) {
1764                 kvm_make_request(KVM_REQ_UNHALT, vcpu);
1765                 return -EINTR;
1766         }
1767         if (kvm_cpu_has_pending_timer(vcpu))
1768                 return -EINTR;
1769         if (signal_pending(current))
1770                 return -EINTR;
1771
1772         return 0;
1773 }
1774
1775 /*
1776  * The vCPU has executed a HLT instruction with in-kernel mode enabled.
1777  */
1778 void kvm_vcpu_block(struct kvm_vcpu *vcpu)
1779 {
1780         ktime_t start, cur;
1781         DEFINE_WAIT(wait);
1782         bool waited = false;
1783
1784         start = cur = ktime_get();
1785         if (halt_poll_ns) {
1786                 ktime_t stop = ktime_add_ns(ktime_get(), halt_poll_ns);
1787
1788                 do {
1789                         /*
1790                          * This sets KVM_REQ_UNHALT if an interrupt
1791                          * arrives.
1792                          */
1793                         if (kvm_vcpu_check_block(vcpu) < 0) {
1794                                 ++vcpu->stat.halt_successful_poll;
1795                                 goto out;
1796                         }
1797                         cur = ktime_get();
1798                 } while (single_task_running() && ktime_before(cur, stop));
1799         }
1800
1801         for (;;) {
1802                 prepare_to_wait(&vcpu->wq, &wait, TASK_INTERRUPTIBLE);
1803
1804                 if (kvm_vcpu_check_block(vcpu) < 0)
1805                         break;
1806
1807                 waited = true;
1808                 schedule();
1809         }
1810
1811         finish_wait(&vcpu->wq, &wait);
1812         cur = ktime_get();
1813
1814 out:
1815         trace_kvm_vcpu_wakeup(ktime_to_ns(cur) - ktime_to_ns(start), waited);
1816 }
1817 EXPORT_SYMBOL_GPL(kvm_vcpu_block);
1818
1819 #ifndef CONFIG_S390
1820 /*
1821  * Kick a sleeping VCPU, or a guest VCPU in guest mode, into host kernel mode.
1822  */
1823 void kvm_vcpu_kick(struct kvm_vcpu *vcpu)
1824 {
1825         int me;
1826         int cpu = vcpu->cpu;
1827         wait_queue_head_t *wqp;
1828
1829         wqp = kvm_arch_vcpu_wq(vcpu);
1830         if (waitqueue_active(wqp)) {
1831                 wake_up_interruptible(wqp);
1832                 ++vcpu->stat.halt_wakeup;
1833         }
1834
1835         me = get_cpu();
1836         if (cpu != me && (unsigned)cpu < nr_cpu_ids && cpu_online(cpu))
1837                 if (kvm_arch_vcpu_should_kick(vcpu))
1838                         smp_send_reschedule(cpu);
1839         put_cpu();
1840 }
1841 EXPORT_SYMBOL_GPL(kvm_vcpu_kick);
1842 #endif /* !CONFIG_S390 */
1843
1844 int kvm_vcpu_yield_to(struct kvm_vcpu *target)
1845 {
1846         struct pid *pid;
1847         struct task_struct *task = NULL;
1848         int ret = 0;
1849
1850         rcu_read_lock();
1851         pid = rcu_dereference(target->pid);
1852         if (pid)
1853                 task = get_pid_task(pid, PIDTYPE_PID);
1854         rcu_read_unlock();
1855         if (!task)
1856                 return ret;
1857         ret = yield_to(task, 1);
1858         put_task_struct(task);
1859
1860         return ret;
1861 }
1862 EXPORT_SYMBOL_GPL(kvm_vcpu_yield_to);
1863
1864 /*
1865  * Helper that checks whether a VCPU is eligible for directed yield.
1866  * Most eligible candidate to yield is decided by following heuristics:
1867  *
1868  *  (a) VCPU which has not done pl-exit or cpu relax intercepted recently
1869  *  (preempted lock holder), indicated by @in_spin_loop.
1870  *  Set at the beiginning and cleared at the end of interception/PLE handler.
1871  *
1872  *  (b) VCPU which has done pl-exit/ cpu relax intercepted but did not get
1873  *  chance last time (mostly it has become eligible now since we have probably
1874  *  yielded to lockholder in last iteration. This is done by toggling
1875  *  @dy_eligible each time a VCPU checked for eligibility.)
1876  *
1877  *  Yielding to a recently pl-exited/cpu relax intercepted VCPU before yielding
1878  *  to preempted lock-holder could result in wrong VCPU selection and CPU
1879  *  burning. Giving priority for a potential lock-holder increases lock
1880  *  progress.
1881  *
1882  *  Since algorithm is based on heuristics, accessing another VCPU data without
1883  *  locking does not harm. It may result in trying to yield to  same VCPU, fail
1884  *  and continue with next VCPU and so on.
1885  */
1886 static bool kvm_vcpu_eligible_for_directed_yield(struct kvm_vcpu *vcpu)
1887 {
1888 #ifdef CONFIG_HAVE_KVM_CPU_RELAX_INTERCEPT
1889         bool eligible;
1890
1891         eligible = !vcpu->spin_loop.in_spin_loop ||
1892                     vcpu->spin_loop.dy_eligible;
1893
1894         if (vcpu->spin_loop.in_spin_loop)
1895                 kvm_vcpu_set_dy_eligible(vcpu, !vcpu->spin_loop.dy_eligible);
1896
1897         return eligible;
1898 #else
1899         return true;
1900 #endif
1901 }
1902
1903 void kvm_vcpu_on_spin(struct kvm_vcpu *me)
1904 {
1905         struct kvm *kvm = me->kvm;
1906         struct kvm_vcpu *vcpu;
1907         int last_boosted_vcpu = me->kvm->last_boosted_vcpu;
1908         int yielded = 0;
1909         int try = 3;
1910         int pass;
1911         int i;
1912
1913         kvm_vcpu_set_in_spin_loop(me, true);
1914         /*
1915          * We boost the priority of a VCPU that is runnable but not
1916          * currently running, because it got preempted by something
1917          * else and called schedule in __vcpu_run.  Hopefully that
1918          * VCPU is holding the lock that we need and will release it.
1919          * We approximate round-robin by starting at the last boosted VCPU.
1920          */
1921         for (pass = 0; pass < 2 && !yielded && try; pass++) {
1922                 kvm_for_each_vcpu(i, vcpu, kvm) {
1923                         if (!pass && i <= last_boosted_vcpu) {
1924                                 i = last_boosted_vcpu;
1925                                 continue;
1926                         } else if (pass && i > last_boosted_vcpu)
1927                                 break;
1928                         if (!ACCESS_ONCE(vcpu->preempted))
1929                                 continue;
1930                         if (vcpu == me)
1931                                 continue;
1932                         if (waitqueue_active(&vcpu->wq) && !kvm_arch_vcpu_runnable(vcpu))
1933                                 continue;
1934                         if (!kvm_vcpu_eligible_for_directed_yield(vcpu))
1935                                 continue;
1936
1937                         yielded = kvm_vcpu_yield_to(vcpu);
1938                         if (yielded > 0) {
1939                                 kvm->last_boosted_vcpu = i;
1940                                 break;
1941                         } else if (yielded < 0) {
1942                                 try--;
1943                                 if (!try)
1944                                         break;
1945                         }
1946                 }
1947         }
1948         kvm_vcpu_set_in_spin_loop(me, false);
1949
1950         /* Ensure vcpu is not eligible during next spinloop */
1951         kvm_vcpu_set_dy_eligible(me, false);
1952 }
1953 EXPORT_SYMBOL_GPL(kvm_vcpu_on_spin);
1954
1955 static int kvm_vcpu_fault(struct vm_area_struct *vma, struct vm_fault *vmf)
1956 {
1957         struct kvm_vcpu *vcpu = vma->vm_file->private_data;
1958         struct page *page;
1959
1960         if (vmf->pgoff == 0)
1961                 page = virt_to_page(vcpu->run);
1962 #ifdef CONFIG_X86
1963         else if (vmf->pgoff == KVM_PIO_PAGE_OFFSET)
1964                 page = virt_to_page(vcpu->arch.pio_data);
1965 #endif
1966 #ifdef KVM_COALESCED_MMIO_PAGE_OFFSET
1967         else if (vmf->pgoff == KVM_COALESCED_MMIO_PAGE_OFFSET)
1968                 page = virt_to_page(vcpu->kvm->coalesced_mmio_ring);
1969 #endif
1970         else
1971                 return kvm_arch_vcpu_fault(vcpu, vmf);
1972         get_page(page);
1973         vmf->page = page;
1974         return 0;
1975 }
1976
1977 static const struct vm_operations_struct kvm_vcpu_vm_ops = {
1978         .fault = kvm_vcpu_fault,
1979 };
1980
1981 static int kvm_vcpu_mmap(struct file *file, struct vm_area_struct *vma)
1982 {
1983         vma->vm_ops = &kvm_vcpu_vm_ops;
1984         return 0;
1985 }
1986
1987 static int kvm_vcpu_release(struct inode *inode, struct file *filp)
1988 {
1989         struct kvm_vcpu *vcpu = filp->private_data;
1990
1991         kvm_put_kvm(vcpu->kvm);
1992         return 0;
1993 }
1994
1995 static struct file_operations kvm_vcpu_fops = {
1996         .release        = kvm_vcpu_release,
1997         .unlocked_ioctl = kvm_vcpu_ioctl,
1998 #ifdef CONFIG_KVM_COMPAT
1999         .compat_ioctl   = kvm_vcpu_compat_ioctl,
2000 #endif
2001         .mmap           = kvm_vcpu_mmap,
2002         .llseek         = noop_llseek,
2003 };
2004
2005 /*
2006  * Allocates an inode for the vcpu.
2007  */
2008 static int create_vcpu_fd(struct kvm_vcpu *vcpu)
2009 {
2010         return anon_inode_getfd("kvm-vcpu", &kvm_vcpu_fops, vcpu, O_RDWR | O_CLOEXEC);
2011 }
2012
2013 /*
2014  * Creates some virtual cpus.  Good luck creating more than one.
2015  */
2016 static int kvm_vm_ioctl_create_vcpu(struct kvm *kvm, u32 id)
2017 {
2018         int r;
2019         struct kvm_vcpu *vcpu, *v;
2020
2021         if (id >= KVM_MAX_VCPUS)
2022                 return -EINVAL;
2023
2024         vcpu = kvm_arch_vcpu_create(kvm, id);
2025         if (IS_ERR(vcpu))
2026                 return PTR_ERR(vcpu);
2027
2028         preempt_notifier_init(&vcpu->preempt_notifier, &kvm_preempt_ops);
2029
2030         r = kvm_arch_vcpu_setup(vcpu);
2031         if (r)
2032                 goto vcpu_destroy;
2033
2034         mutex_lock(&kvm->lock);
2035         if (!kvm_vcpu_compatible(vcpu)) {
2036                 r = -EINVAL;
2037                 goto unlock_vcpu_destroy;
2038         }
2039         if (atomic_read(&kvm->online_vcpus) == KVM_MAX_VCPUS) {
2040                 r = -EINVAL;
2041                 goto unlock_vcpu_destroy;
2042         }
2043
2044         kvm_for_each_vcpu(r, v, kvm)
2045                 if (v->vcpu_id == id) {
2046                         r = -EEXIST;
2047                         goto unlock_vcpu_destroy;
2048                 }
2049
2050         BUG_ON(kvm->vcpus[atomic_read(&kvm->online_vcpus)]);
2051
2052         /* Now it's all set up, let userspace reach it */
2053         kvm_get_kvm(kvm);
2054         r = create_vcpu_fd(vcpu);
2055         if (r < 0) {
2056                 kvm_put_kvm(kvm);
2057                 goto unlock_vcpu_destroy;
2058         }
2059
2060         kvm->vcpus[atomic_read(&kvm->online_vcpus)] = vcpu;
2061         smp_wmb();
2062         atomic_inc(&kvm->online_vcpus);
2063
2064         mutex_unlock(&kvm->lock);
2065         kvm_arch_vcpu_postcreate(vcpu);
2066         return r;
2067
2068 unlock_vcpu_destroy:
2069         mutex_unlock(&kvm->lock);
2070 vcpu_destroy:
2071         kvm_arch_vcpu_destroy(vcpu);
2072         return r;
2073 }
2074
2075 static int kvm_vcpu_ioctl_set_sigmask(struct kvm_vcpu *vcpu, sigset_t *sigset)
2076 {
2077         if (sigset) {
2078                 sigdelsetmask(sigset, sigmask(SIGKILL)|sigmask(SIGSTOP));
2079                 vcpu->sigset_active = 1;
2080                 vcpu->sigset = *sigset;
2081         } else
2082                 vcpu->sigset_active = 0;
2083         return 0;
2084 }
2085
2086 static long kvm_vcpu_ioctl(struct file *filp,
2087                            unsigned int ioctl, unsigned long arg)
2088 {
2089         struct kvm_vcpu *vcpu = filp->private_data;
2090         void __user *argp = (void __user *)arg;
2091         int r;
2092         struct kvm_fpu *fpu = NULL;
2093         struct kvm_sregs *kvm_sregs = NULL;
2094
2095         if (vcpu->kvm->mm != current->mm)
2096                 return -EIO;
2097
2098         if (unlikely(_IOC_TYPE(ioctl) != KVMIO))
2099                 return -EINVAL;
2100
2101 #if defined(CONFIG_S390) || defined(CONFIG_PPC) || defined(CONFIG_MIPS)
2102         /*
2103          * Special cases: vcpu ioctls that are asynchronous to vcpu execution,
2104          * so vcpu_load() would break it.
2105          */
2106         if (ioctl == KVM_S390_INTERRUPT || ioctl == KVM_S390_IRQ || ioctl == KVM_INTERRUPT)
2107                 return kvm_arch_vcpu_ioctl(filp, ioctl, arg);
2108 #endif
2109
2110
2111         r = vcpu_load(vcpu);
2112         if (r)
2113                 return r;
2114         switch (ioctl) {
2115         case KVM_RUN:
2116                 r = -EINVAL;
2117                 if (arg)
2118                         goto out;
2119                 if (unlikely(vcpu->pid != current->pids[PIDTYPE_PID].pid)) {
2120                         /* The thread running this VCPU changed. */
2121                         struct pid *oldpid = vcpu->pid;
2122                         struct pid *newpid = get_task_pid(current, PIDTYPE_PID);
2123
2124                         rcu_assign_pointer(vcpu->pid, newpid);
2125                         if (oldpid)
2126                                 synchronize_rcu();
2127                         put_pid(oldpid);
2128                 }
2129                 r = kvm_arch_vcpu_ioctl_run(vcpu, vcpu->run);
2130                 trace_kvm_userspace_exit(vcpu->run->exit_reason, r);
2131                 break;
2132         case KVM_GET_REGS: {
2133                 struct kvm_regs *kvm_regs;
2134
2135                 r = -ENOMEM;
2136                 kvm_regs = kzalloc(sizeof(struct kvm_regs), GFP_KERNEL);
2137                 if (!kvm_regs)
2138                         goto out;
2139                 r = kvm_arch_vcpu_ioctl_get_regs(vcpu, kvm_regs);
2140                 if (r)
2141                         goto out_free1;
2142                 r = -EFAULT;
2143                 if (copy_to_user(argp, kvm_regs, sizeof(struct kvm_regs)))
2144                         goto out_free1;
2145                 r = 0;
2146 out_free1:
2147                 kfree(kvm_regs);
2148                 break;
2149         }
2150         case KVM_SET_REGS: {
2151                 struct kvm_regs *kvm_regs;
2152
2153                 r = -ENOMEM;
2154                 kvm_regs = memdup_user(argp, sizeof(*kvm_regs));
2155                 if (IS_ERR(kvm_regs)) {
2156                         r = PTR_ERR(kvm_regs);
2157                         goto out;
2158                 }
2159                 r = kvm_arch_vcpu_ioctl_set_regs(vcpu, kvm_regs);
2160                 kfree(kvm_regs);
2161                 break;
2162         }
2163         case KVM_GET_SREGS: {
2164                 kvm_sregs = kzalloc(sizeof(struct kvm_sregs), GFP_KERNEL);
2165                 r = -ENOMEM;
2166                 if (!kvm_sregs)
2167                         goto out;
2168                 r = kvm_arch_vcpu_ioctl_get_sregs(vcpu, kvm_sregs);
2169                 if (r)
2170                         goto out;
2171                 r = -EFAULT;
2172                 if (copy_to_user(argp, kvm_sregs, sizeof(struct kvm_sregs)))
2173                         goto out;
2174                 r = 0;
2175                 break;
2176         }
2177         case KVM_SET_SREGS: {
2178                 kvm_sregs = memdup_user(argp, sizeof(*kvm_sregs));
2179                 if (IS_ERR(kvm_sregs)) {
2180                         r = PTR_ERR(kvm_sregs);
2181                         kvm_sregs = NULL;
2182                         goto out;
2183                 }
2184                 r = kvm_arch_vcpu_ioctl_set_sregs(vcpu, kvm_sregs);
2185                 break;
2186         }
2187         case KVM_GET_MP_STATE: {
2188                 struct kvm_mp_state mp_state;
2189
2190                 r = kvm_arch_vcpu_ioctl_get_mpstate(vcpu, &mp_state);
2191                 if (r)
2192                         goto out;
2193                 r = -EFAULT;
2194                 if (copy_to_user(argp, &mp_state, sizeof(mp_state)))
2195                         goto out;
2196                 r = 0;
2197                 break;
2198         }
2199         case KVM_SET_MP_STATE: {
2200                 struct kvm_mp_state mp_state;
2201
2202                 r = -EFAULT;
2203                 if (copy_from_user(&mp_state, argp, sizeof(mp_state)))
2204                         goto out;
2205                 r = kvm_arch_vcpu_ioctl_set_mpstate(vcpu, &mp_state);
2206                 break;
2207         }
2208         case KVM_TRANSLATE: {
2209                 struct kvm_translation tr;
2210
2211                 r = -EFAULT;
2212                 if (copy_from_user(&tr, argp, sizeof(tr)))
2213                         goto out;
2214                 r = kvm_arch_vcpu_ioctl_translate(vcpu, &tr);
2215                 if (r)
2216                         goto out;
2217                 r = -EFAULT;
2218                 if (copy_to_user(argp, &tr, sizeof(tr)))
2219                         goto out;
2220                 r = 0;
2221                 break;
2222         }
2223         case KVM_SET_GUEST_DEBUG: {
2224                 struct kvm_guest_debug dbg;
2225
2226                 r = -EFAULT;
2227                 if (copy_from_user(&dbg, argp, sizeof(dbg)))
2228                         goto out;
2229                 r = kvm_arch_vcpu_ioctl_set_guest_debug(vcpu, &dbg);
2230                 break;
2231         }
2232         case KVM_SET_SIGNAL_MASK: {
2233                 struct kvm_signal_mask __user *sigmask_arg = argp;
2234                 struct kvm_signal_mask kvm_sigmask;
2235                 sigset_t sigset, *p;
2236
2237                 p = NULL;
2238                 if (argp) {
2239                         r = -EFAULT;
2240                         if (copy_from_user(&kvm_sigmask, argp,
2241                                            sizeof(kvm_sigmask)))
2242                                 goto out;
2243                         r = -EINVAL;
2244                         if (kvm_sigmask.len != sizeof(sigset))
2245                                 goto out;
2246                         r = -EFAULT;
2247                         if (copy_from_user(&sigset, sigmask_arg->sigset,
2248                                            sizeof(sigset)))
2249                                 goto out;
2250                         p = &sigset;
2251                 }
2252                 r = kvm_vcpu_ioctl_set_sigmask(vcpu, p);
2253                 break;
2254         }
2255         case KVM_GET_FPU: {
2256                 fpu = kzalloc(sizeof(struct kvm_fpu), GFP_KERNEL);
2257                 r = -ENOMEM;
2258                 if (!fpu)
2259                         goto out;
2260                 r = kvm_arch_vcpu_ioctl_get_fpu(vcpu, fpu);
2261                 if (r)
2262                         goto out;
2263                 r = -EFAULT;
2264                 if (copy_to_user(argp, fpu, sizeof(struct kvm_fpu)))
2265                         goto out;
2266                 r = 0;
2267                 break;
2268         }
2269         case KVM_SET_FPU: {
2270                 fpu = memdup_user(argp, sizeof(*fpu));
2271                 if (IS_ERR(fpu)) {
2272                         r = PTR_ERR(fpu);
2273                         fpu = NULL;
2274                         goto out;
2275                 }
2276                 r = kvm_arch_vcpu_ioctl_set_fpu(vcpu, fpu);
2277                 break;
2278         }
2279         default:
2280                 r = kvm_arch_vcpu_ioctl(filp, ioctl, arg);
2281         }
2282 out:
2283         vcpu_put(vcpu);
2284         kfree(fpu);
2285         kfree(kvm_sregs);
2286         return r;
2287 }
2288
2289 #ifdef CONFIG_KVM_COMPAT
2290 static long kvm_vcpu_compat_ioctl(struct file *filp,
2291                                   unsigned int ioctl, unsigned long arg)
2292 {
2293         struct kvm_vcpu *vcpu = filp->private_data;
2294         void __user *argp = compat_ptr(arg);
2295         int r;
2296
2297         if (vcpu->kvm->mm != current->mm)
2298                 return -EIO;
2299
2300         switch (ioctl) {
2301         case KVM_SET_SIGNAL_MASK: {
2302                 struct kvm_signal_mask __user *sigmask_arg = argp;
2303                 struct kvm_signal_mask kvm_sigmask;
2304                 compat_sigset_t csigset;
2305                 sigset_t sigset;
2306
2307                 if (argp) {
2308                         r = -EFAULT;
2309                         if (copy_from_user(&kvm_sigmask, argp,
2310                                            sizeof(kvm_sigmask)))
2311                                 goto out;
2312                         r = -EINVAL;
2313                         if (kvm_sigmask.len != sizeof(csigset))
2314                                 goto out;
2315                         r = -EFAULT;
2316                         if (copy_from_user(&csigset, sigmask_arg->sigset,
2317                                            sizeof(csigset)))
2318                                 goto out;
2319                         sigset_from_compat(&sigset, &csigset);
2320                         r = kvm_vcpu_ioctl_set_sigmask(vcpu, &sigset);
2321                 } else
2322                         r = kvm_vcpu_ioctl_set_sigmask(vcpu, NULL);
2323                 break;
2324         }
2325         default:
2326                 r = kvm_vcpu_ioctl(filp, ioctl, arg);
2327         }
2328
2329 out:
2330         return r;
2331 }
2332 #endif
2333
2334 static int kvm_device_ioctl_attr(struct kvm_device *dev,
2335                                  int (*accessor)(struct kvm_device *dev,
2336                                                  struct kvm_device_attr *attr),
2337                                  unsigned long arg)
2338 {
2339         struct kvm_device_attr attr;
2340
2341         if (!accessor)
2342                 return -EPERM;
2343
2344         if (copy_from_user(&attr, (void __user *)arg, sizeof(attr)))
2345                 return -EFAULT;
2346
2347         return accessor(dev, &attr);
2348 }
2349
2350 static long kvm_device_ioctl(struct file *filp, unsigned int ioctl,
2351                              unsigned long arg)
2352 {
2353         struct kvm_device *dev = filp->private_data;
2354
2355         switch (ioctl) {
2356         case KVM_SET_DEVICE_ATTR:
2357                 return kvm_device_ioctl_attr(dev, dev->ops->set_attr, arg);
2358         case KVM_GET_DEVICE_ATTR:
2359                 return kvm_device_ioctl_attr(dev, dev->ops->get_attr, arg);
2360         case KVM_HAS_DEVICE_ATTR:
2361                 return kvm_device_ioctl_attr(dev, dev->ops->has_attr, arg);
2362         default:
2363                 if (dev->ops->ioctl)
2364                         return dev->ops->ioctl(dev, ioctl, arg);
2365
2366                 return -ENOTTY;
2367         }
2368 }
2369
2370 static int kvm_device_release(struct inode *inode, struct file *filp)
2371 {
2372         struct kvm_device *dev = filp->private_data;
2373         struct kvm *kvm = dev->kvm;
2374
2375         kvm_put_kvm(kvm);
2376         return 0;
2377 }
2378
2379 static const struct file_operations kvm_device_fops = {
2380         .unlocked_ioctl = kvm_device_ioctl,
2381 #ifdef CONFIG_KVM_COMPAT
2382         .compat_ioctl = kvm_device_ioctl,
2383 #endif
2384         .release = kvm_device_release,
2385 };
2386
2387 struct kvm_device *kvm_device_from_filp(struct file *filp)
2388 {
2389         if (filp->f_op != &kvm_device_fops)
2390                 return NULL;
2391
2392         return filp->private_data;
2393 }
2394
2395 static struct kvm_device_ops *kvm_device_ops_table[KVM_DEV_TYPE_MAX] = {
2396 #ifdef CONFIG_KVM_MPIC
2397         [KVM_DEV_TYPE_FSL_MPIC_20]      = &kvm_mpic_ops,
2398         [KVM_DEV_TYPE_FSL_MPIC_42]      = &kvm_mpic_ops,
2399 #endif
2400
2401 #ifdef CONFIG_KVM_XICS
2402         [KVM_DEV_TYPE_XICS]             = &kvm_xics_ops,
2403 #endif
2404 };
2405
2406 int kvm_register_device_ops(struct kvm_device_ops *ops, u32 type)
2407 {
2408         if (type >= ARRAY_SIZE(kvm_device_ops_table))
2409                 return -ENOSPC;
2410
2411         if (kvm_device_ops_table[type] != NULL)
2412                 return -EEXIST;
2413
2414         kvm_device_ops_table[type] = ops;
2415         return 0;
2416 }
2417
2418 void kvm_unregister_device_ops(u32 type)
2419 {
2420         if (kvm_device_ops_table[type] != NULL)
2421                 kvm_device_ops_table[type] = NULL;
2422 }
2423
2424 static int kvm_ioctl_create_device(struct kvm *kvm,
2425                                    struct kvm_create_device *cd)
2426 {
2427         struct kvm_device_ops *ops = NULL;
2428         struct kvm_device *dev;
2429         bool test = cd->flags & KVM_CREATE_DEVICE_TEST;
2430         int ret;
2431
2432         if (cd->type >= ARRAY_SIZE(kvm_device_ops_table))
2433                 return -ENODEV;
2434
2435         ops = kvm_device_ops_table[cd->type];
2436         if (ops == NULL)
2437                 return -ENODEV;
2438
2439         if (test)
2440                 return 0;
2441
2442         dev = kzalloc(sizeof(*dev), GFP_KERNEL);
2443         if (!dev)
2444                 return -ENOMEM;
2445
2446         dev->ops = ops;
2447         dev->kvm = kvm;
2448
2449         ret = ops->create(dev, cd->type);
2450         if (ret < 0) {
2451                 kfree(dev);
2452                 return ret;
2453         }
2454
2455         ret = anon_inode_getfd(ops->name, &kvm_device_fops, dev, O_RDWR | O_CLOEXEC);
2456         if (ret < 0) {
2457                 ops->destroy(dev);
2458                 return ret;
2459         }
2460
2461         list_add(&dev->vm_node, &kvm->devices);
2462         kvm_get_kvm(kvm);
2463         cd->fd = ret;
2464         return 0;
2465 }
2466
2467 static long kvm_vm_ioctl_check_extension_generic(struct kvm *kvm, long arg)
2468 {
2469         switch (arg) {
2470         case KVM_CAP_USER_MEMORY:
2471         case KVM_CAP_DESTROY_MEMORY_REGION_WORKS:
2472         case KVM_CAP_JOIN_MEMORY_REGIONS_WORKS:
2473 #ifdef CONFIG_KVM_APIC_ARCHITECTURE
2474         case KVM_CAP_SET_BOOT_CPU_ID:
2475 #endif
2476         case KVM_CAP_INTERNAL_ERROR_DATA:
2477 #ifdef CONFIG_HAVE_KVM_MSI
2478         case KVM_CAP_SIGNAL_MSI:
2479 #endif
2480 #ifdef CONFIG_HAVE_KVM_IRQFD
2481         case KVM_CAP_IRQFD_RESAMPLE:
2482 #endif
2483         case KVM_CAP_CHECK_EXTENSION_VM:
2484                 return 1;
2485 #ifdef CONFIG_HAVE_KVM_IRQ_ROUTING
2486         case KVM_CAP_IRQ_ROUTING:
2487                 return KVM_MAX_IRQ_ROUTES;
2488 #endif
2489         default:
2490                 break;
2491         }
2492         return kvm_vm_ioctl_check_extension(kvm, arg);
2493 }
2494
2495 static long kvm_vm_ioctl(struct file *filp,
2496                            unsigned int ioctl, unsigned long arg)
2497 {
2498         struct kvm *kvm = filp->private_data;
2499         void __user *argp = (void __user *)arg;
2500         int r;
2501
2502         if (kvm->mm != current->mm)
2503                 return -EIO;
2504         switch (ioctl) {
2505         case KVM_CREATE_VCPU:
2506                 r = kvm_vm_ioctl_create_vcpu(kvm, arg);
2507                 break;
2508         case KVM_SET_USER_MEMORY_REGION: {
2509                 struct kvm_userspace_memory_region kvm_userspace_mem;
2510
2511                 r = -EFAULT;
2512                 if (copy_from_user(&kvm_userspace_mem, argp,
2513                                                 sizeof(kvm_userspace_mem)))
2514                         goto out;
2515
2516                 r = kvm_vm_ioctl_set_memory_region(kvm, &kvm_userspace_mem);
2517                 break;
2518         }
2519         case KVM_GET_DIRTY_LOG: {
2520                 struct kvm_dirty_log log;
2521
2522                 r = -EFAULT;
2523                 if (copy_from_user(&log, argp, sizeof(log)))
2524                         goto out;
2525                 r = kvm_vm_ioctl_get_dirty_log(kvm, &log);
2526                 break;
2527         }
2528 #ifdef KVM_COALESCED_MMIO_PAGE_OFFSET
2529         case KVM_REGISTER_COALESCED_MMIO: {
2530                 struct kvm_coalesced_mmio_zone zone;
2531
2532                 r = -EFAULT;
2533                 if (copy_from_user(&zone, argp, sizeof(zone)))
2534                         goto out;
2535                 r = kvm_vm_ioctl_register_coalesced_mmio(kvm, &zone);
2536                 break;
2537         }
2538         case KVM_UNREGISTER_COALESCED_MMIO: {
2539                 struct kvm_coalesced_mmio_zone zone;
2540
2541                 r = -EFAULT;
2542                 if (copy_from_user(&zone, argp, sizeof(zone)))
2543                         goto out;
2544                 r = kvm_vm_ioctl_unregister_coalesced_mmio(kvm, &zone);
2545                 break;
2546         }
2547 #endif
2548         case KVM_IRQFD: {
2549                 struct kvm_irqfd data;
2550
2551                 r = -EFAULT;
2552                 if (copy_from_user(&data, argp, sizeof(data)))
2553                         goto out;
2554                 r = kvm_irqfd(kvm, &data);
2555                 break;
2556         }
2557         case KVM_IOEVENTFD: {
2558                 struct kvm_ioeventfd data;
2559
2560                 r = -EFAULT;
2561                 if (copy_from_user(&data, argp, sizeof(data)))
2562                         goto out;
2563                 r = kvm_ioeventfd(kvm, &data);
2564                 break;
2565         }
2566 #ifdef CONFIG_KVM_APIC_ARCHITECTURE
2567         case KVM_SET_BOOT_CPU_ID:
2568                 r = 0;
2569                 mutex_lock(&kvm->lock);
2570                 if (atomic_read(&kvm->online_vcpus) != 0)
2571                         r = -EBUSY;
2572                 else
2573                         kvm->bsp_vcpu_id = arg;
2574                 mutex_unlock(&kvm->lock);
2575                 break;
2576 #endif
2577 #ifdef CONFIG_HAVE_KVM_MSI
2578         case KVM_SIGNAL_MSI: {
2579                 struct kvm_msi msi;
2580
2581                 r = -EFAULT;
2582                 if (copy_from_user(&msi, argp, sizeof(msi)))
2583                         goto out;
2584                 r = kvm_send_userspace_msi(kvm, &msi);
2585                 break;
2586         }
2587 #endif
2588 #ifdef __KVM_HAVE_IRQ_LINE
2589         case KVM_IRQ_LINE_STATUS:
2590         case KVM_IRQ_LINE: {
2591                 struct kvm_irq_level irq_event;
2592
2593                 r = -EFAULT;
2594                 if (copy_from_user(&irq_event, argp, sizeof(irq_event)))
2595                         goto out;
2596
2597                 r = kvm_vm_ioctl_irq_line(kvm, &irq_event,
2598                                         ioctl == KVM_IRQ_LINE_STATUS);
2599                 if (r)
2600                         goto out;
2601
2602                 r = -EFAULT;
2603                 if (ioctl == KVM_IRQ_LINE_STATUS) {
2604                         if (copy_to_user(argp, &irq_event, sizeof(irq_event)))
2605                                 goto out;
2606                 }
2607
2608                 r = 0;
2609                 break;
2610         }
2611 #endif
2612 #ifdef CONFIG_HAVE_KVM_IRQ_ROUTING
2613         case KVM_SET_GSI_ROUTING: {
2614                 struct kvm_irq_routing routing;
2615                 struct kvm_irq_routing __user *urouting;
2616                 struct kvm_irq_routing_entry *entries;
2617
2618                 r = -EFAULT;
2619                 if (copy_from_user(&routing, argp, sizeof(routing)))
2620                         goto out;
2621                 r = -EINVAL;
2622                 if (routing.nr >= KVM_MAX_IRQ_ROUTES)
2623                         goto out;
2624                 if (routing.flags)
2625                         goto out;
2626                 r = -ENOMEM;
2627                 entries = vmalloc(routing.nr * sizeof(*entries));
2628                 if (!entries)
2629                         goto out;
2630                 r = -EFAULT;
2631                 urouting = argp;
2632                 if (copy_from_user(entries, urouting->entries,
2633                                    routing.nr * sizeof(*entries)))
2634                         goto out_free_irq_routing;
2635                 r = kvm_set_irq_routing(kvm, entries, routing.nr,
2636                                         routing.flags);
2637 out_free_irq_routing:
2638                 vfree(entries);
2639                 break;
2640         }
2641 #endif /* CONFIG_HAVE_KVM_IRQ_ROUTING */
2642         case KVM_CREATE_DEVICE: {
2643                 struct kvm_create_device cd;
2644
2645                 r = -EFAULT;
2646                 if (copy_from_user(&cd, argp, sizeof(cd)))
2647                         goto out;
2648
2649                 r = kvm_ioctl_create_device(kvm, &cd);
2650                 if (r)
2651                         goto out;
2652
2653                 r = -EFAULT;
2654                 if (copy_to_user(argp, &cd, sizeof(cd)))
2655                         goto out;
2656
2657                 r = 0;
2658                 break;
2659         }
2660         case KVM_CHECK_EXTENSION:
2661                 r = kvm_vm_ioctl_check_extension_generic(kvm, arg);
2662                 break;
2663         default:
2664                 r = kvm_arch_vm_ioctl(filp, ioctl, arg);
2665         }
2666 out:
2667         return r;
2668 }
2669
2670 #ifdef CONFIG_KVM_COMPAT
2671 struct compat_kvm_dirty_log {
2672         __u32 slot;
2673         __u32 padding1;
2674         union {
2675                 compat_uptr_t dirty_bitmap; /* one bit per page */
2676                 __u64 padding2;
2677         };
2678 };
2679
2680 static long kvm_vm_compat_ioctl(struct file *filp,
2681                            unsigned int ioctl, unsigned long arg)
2682 {
2683         struct kvm *kvm = filp->private_data;
2684         int r;
2685
2686         if (kvm->mm != current->mm)
2687                 return -EIO;
2688         switch (ioctl) {
2689         case KVM_GET_DIRTY_LOG: {
2690                 struct compat_kvm_dirty_log compat_log;
2691                 struct kvm_dirty_log log;
2692
2693                 r = -EFAULT;
2694                 if (copy_from_user(&compat_log, (void __user *)arg,
2695                                    sizeof(compat_log)))
2696                         goto out;
2697                 log.slot         = compat_log.slot;
2698                 log.padding1     = compat_log.padding1;
2699                 log.padding2     = compat_log.padding2;
2700                 log.dirty_bitmap = compat_ptr(compat_log.dirty_bitmap);
2701
2702                 r = kvm_vm_ioctl_get_dirty_log(kvm, &log);
2703                 break;
2704         }
2705         default:
2706                 r = kvm_vm_ioctl(filp, ioctl, arg);
2707         }
2708
2709 out:
2710         return r;
2711 }
2712 #endif
2713
2714 static struct file_operations kvm_vm_fops = {
2715         .release        = kvm_vm_release,
2716         .unlocked_ioctl = kvm_vm_ioctl,
2717 #ifdef CONFIG_KVM_COMPAT
2718         .compat_ioctl   = kvm_vm_compat_ioctl,
2719 #endif
2720         .llseek         = noop_llseek,
2721 };
2722
2723 static int kvm_dev_ioctl_create_vm(unsigned long type)
2724 {
2725         int r;
2726         struct kvm *kvm;
2727
2728         kvm = kvm_create_vm(type);
2729         if (IS_ERR(kvm))
2730                 return PTR_ERR(kvm);
2731 #ifdef KVM_COALESCED_MMIO_PAGE_OFFSET
2732         r = kvm_coalesced_mmio_init(kvm);
2733         if (r < 0) {
2734                 kvm_put_kvm(kvm);
2735                 return r;
2736         }
2737 #endif
2738         r = anon_inode_getfd("kvm-vm", &kvm_vm_fops, kvm, O_RDWR | O_CLOEXEC);
2739         if (r < 0)
2740                 kvm_put_kvm(kvm);
2741
2742         return r;
2743 }
2744
2745 static long kvm_dev_ioctl(struct file *filp,
2746                           unsigned int ioctl, unsigned long arg)
2747 {
2748         long r = -EINVAL;
2749
2750         switch (ioctl) {
2751         case KVM_GET_API_VERSION:
2752                 if (arg)
2753                         goto out;
2754                 r = KVM_API_VERSION;
2755                 break;
2756         case KVM_CREATE_VM:
2757                 r = kvm_dev_ioctl_create_vm(arg);
2758                 break;
2759         case KVM_CHECK_EXTENSION:
2760                 r = kvm_vm_ioctl_check_extension_generic(NULL, arg);
2761                 break;
2762         case KVM_GET_VCPU_MMAP_SIZE:
2763                 if (arg)
2764                         goto out;
2765                 r = PAGE_SIZE;     /* struct kvm_run */
2766 #ifdef CONFIG_X86
2767                 r += PAGE_SIZE;    /* pio data page */
2768 #endif
2769 #ifdef KVM_COALESCED_MMIO_PAGE_OFFSET
2770                 r += PAGE_SIZE;    /* coalesced mmio ring page */
2771 #endif
2772                 break;
2773         case KVM_TRACE_ENABLE:
2774         case KVM_TRACE_PAUSE:
2775         case KVM_TRACE_DISABLE:
2776                 r = -EOPNOTSUPP;
2777                 break;
2778         default:
2779                 return kvm_arch_dev_ioctl(filp, ioctl, arg);
2780         }
2781 out:
2782         return r;
2783 }
2784
2785 static struct file_operations kvm_chardev_ops = {
2786         .unlocked_ioctl = kvm_dev_ioctl,
2787         .compat_ioctl   = kvm_dev_ioctl,
2788         .llseek         = noop_llseek,
2789 };
2790
2791 static struct miscdevice kvm_dev = {
2792         KVM_MINOR,
2793         "kvm",
2794         &kvm_chardev_ops,
2795 };
2796
2797 static void hardware_enable_nolock(void *junk)
2798 {
2799         int cpu = raw_smp_processor_id();
2800         int r;
2801
2802         if (cpumask_test_cpu(cpu, cpus_hardware_enabled))
2803                 return;
2804
2805         cpumask_set_cpu(cpu, cpus_hardware_enabled);
2806
2807         r = kvm_arch_hardware_enable();
2808
2809         if (r) {
2810                 cpumask_clear_cpu(cpu, cpus_hardware_enabled);
2811                 atomic_inc(&hardware_enable_failed);
2812                 pr_info("kvm: enabling virtualization on CPU%d failed\n", cpu);
2813         }
2814 }
2815
2816 static void hardware_enable(void)
2817 {
2818         raw_spin_lock(&kvm_count_lock);
2819         if (kvm_usage_count)
2820                 hardware_enable_nolock(NULL);
2821         raw_spin_unlock(&kvm_count_lock);
2822 }
2823
2824 static void hardware_disable_nolock(void *junk)
2825 {
2826         int cpu = raw_smp_processor_id();
2827
2828         if (!cpumask_test_cpu(cpu, cpus_hardware_enabled))
2829                 return;
2830         cpumask_clear_cpu(cpu, cpus_hardware_enabled);
2831         kvm_arch_hardware_disable();
2832 }
2833
2834 static void hardware_disable(void)
2835 {
2836         raw_spin_lock(&kvm_count_lock);
2837         if (kvm_usage_count)
2838                 hardware_disable_nolock(NULL);
2839         raw_spin_unlock(&kvm_count_lock);
2840 }
2841
2842 static void hardware_disable_all_nolock(void)
2843 {
2844         BUG_ON(!kvm_usage_count);
2845
2846         kvm_usage_count--;
2847         if (!kvm_usage_count)
2848                 on_each_cpu(hardware_disable_nolock, NULL, 1);
2849 }
2850
2851 static void hardware_disable_all(void)
2852 {
2853         raw_spin_lock(&kvm_count_lock);
2854         hardware_disable_all_nolock();
2855         raw_spin_unlock(&kvm_count_lock);
2856 }
2857
2858 static int hardware_enable_all(void)
2859 {
2860         int r = 0;
2861
2862         raw_spin_lock(&kvm_count_lock);
2863
2864         kvm_usage_count++;
2865         if (kvm_usage_count == 1) {
2866                 atomic_set(&hardware_enable_failed, 0);
2867                 on_each_cpu(hardware_enable_nolock, NULL, 1);
2868
2869                 if (atomic_read(&hardware_enable_failed)) {
2870                         hardware_disable_all_nolock();
2871                         r = -EBUSY;
2872                 }
2873         }
2874
2875         raw_spin_unlock(&kvm_count_lock);
2876
2877         return r;
2878 }
2879
2880 static int kvm_cpu_hotplug(struct notifier_block *notifier, unsigned long val,
2881                            void *v)
2882 {
2883         int cpu = (long)v;
2884
2885         val &= ~CPU_TASKS_FROZEN;
2886         switch (val) {
2887         case CPU_DYING:
2888                 pr_info("kvm: disabling virtualization on CPU%d\n",
2889                        cpu);
2890                 hardware_disable();
2891                 break;
2892         case CPU_STARTING:
2893                 pr_info("kvm: enabling virtualization on CPU%d\n",
2894                        cpu);
2895                 hardware_enable();
2896                 break;
2897         }
2898         return NOTIFY_OK;
2899 }
2900
2901 static int kvm_reboot(struct notifier_block *notifier, unsigned long val,
2902                       void *v)
2903 {
2904         /*
2905          * Some (well, at least mine) BIOSes hang on reboot if
2906          * in vmx root mode.
2907          *
2908          * And Intel TXT required VMX off for all cpu when system shutdown.
2909          */
2910         pr_info("kvm: exiting hardware virtualization\n");
2911         kvm_rebooting = true;
2912         on_each_cpu(hardware_disable_nolock, NULL, 1);
2913         return NOTIFY_OK;
2914 }
2915
2916 static struct notifier_block kvm_reboot_notifier = {
2917         .notifier_call = kvm_reboot,
2918         .priority = 0,
2919 };
2920
2921 static void kvm_io_bus_destroy(struct kvm_io_bus *bus)
2922 {
2923         int i;
2924
2925         for (i = 0; i < bus->dev_count; i++) {
2926                 struct kvm_io_device *pos = bus->range[i].dev;
2927
2928                 kvm_iodevice_destructor(pos);
2929         }
2930         kfree(bus);
2931 }
2932
2933 static inline int kvm_io_bus_cmp(const struct kvm_io_range *r1,
2934                                  const struct kvm_io_range *r2)
2935 {
2936         if (r1->addr < r2->addr)
2937                 return -1;
2938         if (r1->addr + r1->len > r2->addr + r2->len)
2939                 return 1;
2940         return 0;
2941 }
2942
2943 static int kvm_io_bus_sort_cmp(const void *p1, const void *p2)
2944 {
2945         return kvm_io_bus_cmp(p1, p2);
2946 }
2947
2948 static int kvm_io_bus_insert_dev(struct kvm_io_bus *bus, struct kvm_io_device *dev,
2949                           gpa_t addr, int len)
2950 {
2951         bus->range[bus->dev_count++] = (struct kvm_io_range) {
2952                 .addr = addr,
2953                 .len = len,
2954                 .dev = dev,
2955         };
2956
2957         sort(bus->range, bus->dev_count, sizeof(struct kvm_io_range),
2958                 kvm_io_bus_sort_cmp, NULL);
2959
2960         return 0;
2961 }
2962
2963 static int kvm_io_bus_get_first_dev(struct kvm_io_bus *bus,
2964                              gpa_t addr, int len)
2965 {
2966         struct kvm_io_range *range, key;
2967         int off;
2968
2969         key = (struct kvm_io_range) {
2970                 .addr = addr,
2971                 .len = len,
2972         };
2973
2974         range = bsearch(&key, bus->range, bus->dev_count,
2975                         sizeof(struct kvm_io_range), kvm_io_bus_sort_cmp);
2976         if (range == NULL)
2977                 return -ENOENT;
2978
2979         off = range - bus->range;
2980
2981         while (off > 0 && kvm_io_bus_cmp(&key, &bus->range[off-1]) == 0)
2982                 off--;
2983
2984         return off;
2985 }
2986
2987 static int __kvm_io_bus_write(struct kvm_vcpu *vcpu, struct kvm_io_bus *bus,
2988                               struct kvm_io_range *range, const void *val)
2989 {
2990         int idx;
2991
2992         idx = kvm_io_bus_get_first_dev(bus, range->addr, range->len);
2993         if (idx < 0)
2994                 return -EOPNOTSUPP;
2995
2996         while (idx < bus->dev_count &&
2997                 kvm_io_bus_cmp(range, &bus->range[idx]) == 0) {
2998                 if (!kvm_iodevice_write(vcpu, bus->range[idx].dev, range->addr,
2999                                         range->len, val))
3000                         return idx;
3001                 idx++;
3002         }
3003
3004         return -EOPNOTSUPP;
3005 }
3006
3007 /* kvm_io_bus_write - called under kvm->slots_lock */
3008 int kvm_io_bus_write(struct kvm_vcpu *vcpu, enum kvm_bus bus_idx, gpa_t addr,
3009                      int len, const void *val)
3010 {
3011         struct kvm_io_bus *bus;
3012         struct kvm_io_range range;
3013         int r;
3014
3015         range = (struct kvm_io_range) {
3016                 .addr = addr,
3017                 .len = len,
3018         };
3019
3020         bus = srcu_dereference(vcpu->kvm->buses[bus_idx], &vcpu->kvm->srcu);
3021         r = __kvm_io_bus_write(vcpu, bus, &range, val);
3022         return r < 0 ? r : 0;
3023 }
3024
3025 /* kvm_io_bus_write_cookie - called under kvm->slots_lock */
3026 int kvm_io_bus_write_cookie(struct kvm_vcpu *vcpu, enum kvm_bus bus_idx,
3027                             gpa_t addr, int len, const void *val, long cookie)
3028 {
3029         struct kvm_io_bus *bus;
3030         struct kvm_io_range range;
3031
3032         range = (struct kvm_io_range) {
3033                 .addr = addr,
3034                 .len = len,
3035         };
3036
3037         bus = srcu_dereference(vcpu->kvm->buses[bus_idx], &vcpu->kvm->srcu);
3038
3039         /* First try the device referenced by cookie. */
3040         if ((cookie >= 0) && (cookie < bus->dev_count) &&
3041             (kvm_io_bus_cmp(&range, &bus->range[cookie]) == 0))
3042                 if (!kvm_iodevice_write(vcpu, bus->range[cookie].dev, addr, len,
3043                                         val))
3044                         return cookie;
3045
3046         /*
3047          * cookie contained garbage; fall back to search and return the
3048          * correct cookie value.
3049          */
3050         return __kvm_io_bus_write(vcpu, bus, &range, val);
3051 }
3052
3053 static int __kvm_io_bus_read(struct kvm_vcpu *vcpu, struct kvm_io_bus *bus,
3054                              struct kvm_io_range *range, void *val)
3055 {
3056         int idx;
3057
3058         idx = kvm_io_bus_get_first_dev(bus, range->addr, range->len);
3059         if (idx < 0)
3060                 return -EOPNOTSUPP;
3061
3062         while (idx < bus->dev_count &&
3063                 kvm_io_bus_cmp(range, &bus->range[idx]) == 0) {
3064                 if (!kvm_iodevice_read(vcpu, bus->range[idx].dev, range->addr,
3065                                        range->len, val))
3066                         return idx;
3067                 idx++;
3068         }
3069
3070         return -EOPNOTSUPP;
3071 }
3072 EXPORT_SYMBOL_GPL(kvm_io_bus_write);
3073
3074 /* kvm_io_bus_read - called under kvm->slots_lock */
3075 int kvm_io_bus_read(struct kvm_vcpu *vcpu, enum kvm_bus bus_idx, gpa_t addr,
3076                     int len, void *val)
3077 {
3078         struct kvm_io_bus *bus;
3079         struct kvm_io_range range;
3080         int r;
3081
3082         range = (struct kvm_io_range) {
3083                 .addr = addr,
3084                 .len = len,
3085         };
3086
3087         bus = srcu_dereference(vcpu->kvm->buses[bus_idx], &vcpu->kvm->srcu);
3088         r = __kvm_io_bus_read(vcpu, bus, &range, val);
3089         return r < 0 ? r : 0;
3090 }
3091
3092
3093 /* Caller must hold slots_lock. */
3094 int kvm_io_bus_register_dev(struct kvm *kvm, enum kvm_bus bus_idx, gpa_t addr,
3095                             int len, struct kvm_io_device *dev)
3096 {
3097         struct kvm_io_bus *new_bus, *bus;
3098
3099         bus = kvm->buses[bus_idx];
3100         /* exclude ioeventfd which is limited by maximum fd */
3101         if (bus->dev_count - bus->ioeventfd_count > NR_IOBUS_DEVS - 1)
3102                 return -ENOSPC;
3103
3104         new_bus = kzalloc(sizeof(*bus) + ((bus->dev_count + 1) *
3105                           sizeof(struct kvm_io_range)), GFP_KERNEL);
3106         if (!new_bus)
3107                 return -ENOMEM;
3108         memcpy(new_bus, bus, sizeof(*bus) + (bus->dev_count *
3109                sizeof(struct kvm_io_range)));
3110         kvm_io_bus_insert_dev(new_bus, dev, addr, len);
3111         rcu_assign_pointer(kvm->buses[bus_idx], new_bus);
3112         synchronize_srcu_expedited(&kvm->srcu);
3113         kfree(bus);
3114
3115         return 0;
3116 }
3117
3118 /* Caller must hold slots_lock. */
3119 int kvm_io_bus_unregister_dev(struct kvm *kvm, enum kvm_bus bus_idx,
3120                               struct kvm_io_device *dev)
3121 {
3122         int i, r;
3123         struct kvm_io_bus *new_bus, *bus;
3124
3125         bus = kvm->buses[bus_idx];
3126         r = -ENOENT;
3127         for (i = 0; i < bus->dev_count; i++)
3128                 if (bus->range[i].dev == dev) {
3129                         r = 0;
3130                         break;
3131                 }
3132
3133         if (r)
3134                 return r;
3135
3136         new_bus = kzalloc(sizeof(*bus) + ((bus->dev_count - 1) *
3137                           sizeof(struct kvm_io_range)), GFP_KERNEL);
3138         if (!new_bus)
3139                 return -ENOMEM;
3140
3141         memcpy(new_bus, bus, sizeof(*bus) + i * sizeof(struct kvm_io_range));
3142         new_bus->dev_count--;
3143         memcpy(new_bus->range + i, bus->range + i + 1,
3144                (new_bus->dev_count - i) * sizeof(struct kvm_io_range));
3145
3146         rcu_assign_pointer(kvm->buses[bus_idx], new_bus);
3147         synchronize_srcu_expedited(&kvm->srcu);
3148         kfree(bus);
3149         return r;
3150 }
3151
3152 static struct notifier_block kvm_cpu_notifier = {
3153         .notifier_call = kvm_cpu_hotplug,
3154 };
3155
3156 static int vm_stat_get(void *_offset, u64 *val)
3157 {
3158         unsigned offset = (long)_offset;
3159         struct kvm *kvm;
3160
3161         *val = 0;
3162         spin_lock(&kvm_lock);
3163         list_for_each_entry(kvm, &vm_list, vm_list)
3164                 *val += *(u32 *)((void *)kvm + offset);
3165         spin_unlock(&kvm_lock);
3166         return 0;
3167 }
3168
3169 DEFINE_SIMPLE_ATTRIBUTE(vm_stat_fops, vm_stat_get, NULL, "%llu\n");
3170
3171 static int vcpu_stat_get(void *_offset, u64 *val)
3172 {
3173         unsigned offset = (long)_offset;
3174         struct kvm *kvm;
3175         struct kvm_vcpu *vcpu;
3176         int i;
3177
3178         *val = 0;
3179         spin_lock(&kvm_lock);
3180         list_for_each_entry(kvm, &vm_list, vm_list)
3181                 kvm_for_each_vcpu(i, vcpu, kvm)
3182                         *val += *(u32 *)((void *)vcpu + offset);
3183
3184         spin_unlock(&kvm_lock);
3185         return 0;
3186 }
3187
3188 DEFINE_SIMPLE_ATTRIBUTE(vcpu_stat_fops, vcpu_stat_get, NULL, "%llu\n");
3189
3190 static const struct file_operations *stat_fops[] = {
3191         [KVM_STAT_VCPU] = &vcpu_stat_fops,
3192         [KVM_STAT_VM]   = &vm_stat_fops,
3193 };
3194
3195 static int kvm_init_debug(void)
3196 {
3197         int r = -EEXIST;
3198         struct kvm_stats_debugfs_item *p;
3199
3200         kvm_debugfs_dir = debugfs_create_dir("kvm", NULL);
3201         if (kvm_debugfs_dir == NULL)
3202                 goto out;
3203
3204         for (p = debugfs_entries; p->name; ++p) {
3205                 p->dentry = debugfs_create_file(p->name, 0444, kvm_debugfs_dir,
3206                                                 (void *)(long)p->offset,
3207                                                 stat_fops[p->kind]);
3208                 if (p->dentry == NULL)
3209                         goto out_dir;
3210         }
3211
3212         return 0;
3213
3214 out_dir:
3215         debugfs_remove_recursive(kvm_debugfs_dir);
3216 out:
3217         return r;
3218 }
3219
3220 static void kvm_exit_debug(void)
3221 {
3222         struct kvm_stats_debugfs_item *p;
3223
3224         for (p = debugfs_entries; p->name; ++p)
3225                 debugfs_remove(p->dentry);
3226         debugfs_remove(kvm_debugfs_dir);
3227 }
3228
3229 static int kvm_suspend(void)
3230 {
3231         if (kvm_usage_count)
3232                 hardware_disable_nolock(NULL);
3233         return 0;
3234 }
3235
3236 static void kvm_resume(void)
3237 {
3238         if (kvm_usage_count) {
3239                 WARN_ON(raw_spin_is_locked(&kvm_count_lock));
3240                 hardware_enable_nolock(NULL);
3241         }
3242 }
3243
3244 static struct syscore_ops kvm_syscore_ops = {
3245         .suspend = kvm_suspend,
3246         .resume = kvm_resume,
3247 };
3248
3249 static inline
3250 struct kvm_vcpu *preempt_notifier_to_vcpu(struct preempt_notifier *pn)
3251 {
3252         return container_of(pn, struct kvm_vcpu, preempt_notifier);
3253 }
3254
3255 static void kvm_sched_in(struct preempt_notifier *pn, int cpu)
3256 {
3257         struct kvm_vcpu *vcpu = preempt_notifier_to_vcpu(pn);
3258
3259         if (vcpu->preempted)
3260                 vcpu->preempted = false;
3261
3262         kvm_arch_sched_in(vcpu, cpu);
3263
3264         kvm_arch_vcpu_load(vcpu, cpu);
3265 }
3266
3267 static void kvm_sched_out(struct preempt_notifier *pn,
3268                           struct task_struct *next)
3269 {
3270         struct kvm_vcpu *vcpu = preempt_notifier_to_vcpu(pn);
3271
3272         if (current->state == TASK_RUNNING)
3273                 vcpu->preempted = true;
3274         kvm_arch_vcpu_put(vcpu);
3275 }
3276
3277 int kvm_init(void *opaque, unsigned vcpu_size, unsigned vcpu_align,
3278                   struct module *module)
3279 {
3280         int r;
3281         int cpu;
3282
3283         r = kvm_arch_init(opaque);
3284         if (r)
3285                 goto out_fail;
3286
3287         /*
3288          * kvm_arch_init makes sure there's at most one caller
3289          * for architectures that support multiple implementations,
3290          * like intel and amd on x86.
3291          * kvm_arch_init must be called before kvm_irqfd_init to avoid creating
3292          * conflicts in case kvm is already setup for another implementation.
3293          */
3294         r = kvm_irqfd_init();
3295         if (r)
3296                 goto out_irqfd;
3297
3298         if (!zalloc_cpumask_var(&cpus_hardware_enabled, GFP_KERNEL)) {
3299                 r = -ENOMEM;
3300                 goto out_free_0;
3301         }
3302
3303         r = kvm_arch_hardware_setup();
3304         if (r < 0)
3305                 goto out_free_0a;
3306
3307         for_each_online_cpu(cpu) {
3308                 smp_call_function_single(cpu,
3309                                 kvm_arch_check_processor_compat,
3310                                 &r, 1);
3311                 if (r < 0)
3312                         goto out_free_1;
3313         }
3314
3315         r = register_cpu_notifier(&kvm_cpu_notifier);
3316         if (r)
3317                 goto out_free_2;
3318         register_reboot_notifier(&kvm_reboot_notifier);
3319
3320         /* A kmem cache lets us meet the alignment requirements of fx_save. */
3321         if (!vcpu_align)
3322                 vcpu_align = __alignof__(struct kvm_vcpu);
3323         kvm_vcpu_cache = kmem_cache_create("kvm_vcpu", vcpu_size, vcpu_align,
3324                                            0, NULL);
3325         if (!kvm_vcpu_cache) {
3326                 r = -ENOMEM;
3327                 goto out_free_3;
3328         }
3329
3330         r = kvm_async_pf_init();
3331         if (r)
3332                 goto out_free;
3333
3334         kvm_chardev_ops.owner = module;
3335         kvm_vm_fops.owner = module;
3336         kvm_vcpu_fops.owner = module;
3337
3338         r = misc_register(&kvm_dev);
3339         if (r) {
3340                 pr_err("kvm: misc device register failed\n");
3341                 goto out_unreg;
3342         }
3343
3344         register_syscore_ops(&kvm_syscore_ops);
3345
3346         kvm_preempt_ops.sched_in = kvm_sched_in;
3347         kvm_preempt_ops.sched_out = kvm_sched_out;
3348
3349         r = kvm_init_debug();
3350         if (r) {
3351                 pr_err("kvm: create debugfs files failed\n");
3352                 goto out_undebugfs;
3353         }
3354
3355         r = kvm_vfio_ops_init();
3356         WARN_ON(r);
3357
3358         return 0;
3359
3360 out_undebugfs:
3361         unregister_syscore_ops(&kvm_syscore_ops);
3362         misc_deregister(&kvm_dev);
3363 out_unreg:
3364         kvm_async_pf_deinit();
3365 out_free:
3366         kmem_cache_destroy(kvm_vcpu_cache);
3367 out_free_3:
3368         unregister_reboot_notifier(&kvm_reboot_notifier);
3369         unregister_cpu_notifier(&kvm_cpu_notifier);
3370 out_free_2:
3371 out_free_1:
3372         kvm_arch_hardware_unsetup();
3373 out_free_0a:
3374         free_cpumask_var(cpus_hardware_enabled);
3375 out_free_0:
3376         kvm_irqfd_exit();
3377 out_irqfd:
3378         kvm_arch_exit();
3379 out_fail:
3380         return r;
3381 }
3382 EXPORT_SYMBOL_GPL(kvm_init);
3383
3384 void kvm_exit(void)
3385 {
3386         kvm_exit_debug();
3387         misc_deregister(&kvm_dev);
3388         kmem_cache_destroy(kvm_vcpu_cache);
3389         kvm_async_pf_deinit();
3390         unregister_syscore_ops(&kvm_syscore_ops);
3391         unregister_reboot_notifier(&kvm_reboot_notifier);
3392         unregister_cpu_notifier(&kvm_cpu_notifier);
3393         on_each_cpu(hardware_disable_nolock, NULL, 1);
3394         kvm_arch_hardware_unsetup();
3395         kvm_arch_exit();
3396         kvm_irqfd_exit();
3397         free_cpumask_var(cpus_hardware_enabled);
3398         kvm_vfio_ops_exit();
3399 }
3400 EXPORT_SYMBOL_GPL(kvm_exit);