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 /* halt polling only reduces halt latency by 5-7 us, 500us is enough */
  70 static unsigned int halt_poll_ns = 500000;
  71 module_param(halt_poll_ns, uint, S_IRUGO | S_IWUSR);
  72
  73 /* Default doubles per-vcpu halt_poll_ns. */
  74 static unsigned int halt_poll_ns_grow = 2;
  75 module_param(halt_poll_ns_grow, int, S_IRUGO);
  76
  77 /* Default resets per-vcpu halt_poll_ns . */
  78 static unsigned int halt_poll_ns_shrink;
  79 module_param(halt_poll_ns_shrink, int, S_IRUGO);
  80
  81 /*
  82  * Ordering of locks:
  83  *
  84  *      kvm->lock --> kvm->slots_lock --> kvm->irq_lock
  85  */
  86
  87 DEFINE_SPINLOCK(kvm_lock);
  88 static DEFINE_RAW_SPINLOCK(kvm_count_lock);
  89 LIST_HEAD(vm_list);
  90
  91 static cpumask_var_t cpus_hardware_enabled;
  92 static int kvm_usage_count;
  93 static atomic_t hardware_enable_failed;
  94
  95 struct kmem_cache *kvm_vcpu_cache;
  96 EXPORT_SYMBOL_GPL(kvm_vcpu_cache);
  97
  98 static __read_mostly struct preempt_ops kvm_preempt_ops;
  99
 100 struct dentry *kvm_debugfs_dir;
 101 EXPORT_SYMBOL_GPL(kvm_debugfs_dir);
 102
 103 static long kvm_vcpu_ioctl(struct file *file, unsigned int ioctl,
 104                            unsigned long arg);
 105 #ifdef CONFIG_KVM_COMPAT
 106 static long kvm_vcpu_compat_ioctl(struct file *file, unsigned int ioctl,
 107                                   unsigned long arg);
 108 #endif
 109 static int hardware_enable_all(void);
 110 static void hardware_disable_all(void);
 111
 112 static void kvm_io_bus_destroy(struct kvm_io_bus *bus);
 113
 114 static void kvm_release_pfn_dirty(pfn_t pfn);
 115 static void mark_page_dirty_in_slot(struct kvm_memory_slot *memslot, gfn_t gfn);
 116
 117 __visible bool kvm_rebooting;
 118 EXPORT_SYMBOL_GPL(kvm_rebooting);
 119
 120 static bool largepages_enabled = true;
 121
 122 bool kvm_is_reserved_pfn(pfn_t pfn)
 123 {
 124         if (pfn_valid(pfn))
 125                 return PageReserved(pfn_to_page(pfn));
 126
 127         return true;
 128 }
 129
 130 /*
 131  * Switches to specified vcpu, until a matching vcpu_put()
 132  */
 133 int vcpu_load(struct kvm_vcpu *vcpu)
 134 {
 135         int cpu;
 136
 137         if (mutex_lock_killable(&vcpu->mutex))
 138                 return -EINTR;
 139         cpu = get_cpu();
 140         preempt_notifier_register(&vcpu->preempt_notifier);
 141         kvm_arch_vcpu_load(vcpu, cpu);
 142         put_cpu();
 143         return 0;
 144 }
 145
 146 void vcpu_put(struct kvm_vcpu *vcpu)
 147 {
 148         preempt_disable();
 149         kvm_arch_vcpu_put(vcpu);
 150         preempt_notifier_unregister(&vcpu->preempt_notifier);
 151         preempt_enable();
 152         mutex_unlock(&vcpu->mutex);
 153 }
 154
 155 static void ack_flush(void *_completed)
 156 {
 157 }
 158
 159 bool kvm_make_all_cpus_request(struct kvm *kvm, unsigned int req)
 160 {
 161         int i, cpu, me;
 162         cpumask_var_t cpus;
 163         bool called = true;
 164         struct kvm_vcpu *vcpu;
 165
 166         zalloc_cpumask_var(&cpus, GFP_ATOMIC);
 167
 168         me = get_cpu();
 169         kvm_for_each_vcpu(i, vcpu, kvm) {
 170                 kvm_make_request(req, vcpu);
 171                 cpu = vcpu->cpu;
 172
 173                 /* Set ->requests bit before we read ->mode */
 174                 smp_mb();
 175
 176                 if (cpus != NULL && cpu != -1 && cpu != me &&
 177                       kvm_vcpu_exiting_guest_mode(vcpu) != OUTSIDE_GUEST_MODE)
 178                         cpumask_set_cpu(cpu, cpus);
 179         }
 180         if (unlikely(cpus == NULL))
 181                 smp_call_function_many(cpu_online_mask, ack_flush, NULL, 1);
 182         else if (!cpumask_empty(cpus))
 183                 smp_call_function_many(cpus, ack_flush, NULL, 1);
 184         else
 185                 called = false;
 186         put_cpu();
 187         free_cpumask_var(cpus);
 188         return called;
 189 }
 190
 191 #ifndef CONFIG_HAVE_KVM_ARCH_TLB_FLUSH_ALL
 192 void kvm_flush_remote_tlbs(struct kvm *kvm)
 193 {
 194         long dirty_count = kvm->tlbs_dirty;
 195
 196         smp_mb();
 197         if (kvm_make_all_cpus_request(kvm, KVM_REQ_TLB_FLUSH))
 198                 ++kvm->stat.remote_tlb_flush;
 199         cmpxchg(&kvm->tlbs_dirty, dirty_count, 0);
 200 }
 201 EXPORT_SYMBOL_GPL(kvm_flush_remote_tlbs);
 202 #endif
 203
 204 void kvm_reload_remote_mmus(struct kvm *kvm)
 205 {
 206         kvm_make_all_cpus_request(kvm, KVM_REQ_MMU_RELOAD);
 207 }
 208
 209 void kvm_make_mclock_inprogress_request(struct kvm *kvm)
 210 {
 211         kvm_make_all_cpus_request(kvm, KVM_REQ_MCLOCK_INPROGRESS);
 212 }
 213
 214 void kvm_make_scan_ioapic_request(struct kvm *kvm)
 215 {
 216         kvm_make_all_cpus_request(kvm, KVM_REQ_SCAN_IOAPIC);
 217 }
 218
 219 int kvm_vcpu_init(struct kvm_vcpu *vcpu, struct kvm *kvm, unsigned id)
 220 {
 221         struct page *page;
 222         int r;
 223
 224         mutex_init(&vcpu->mutex);
 225         vcpu->cpu = -1;
 226         vcpu->kvm = kvm;
 227         vcpu->vcpu_id = id;
 228         vcpu->pid = NULL;
 229         vcpu->halt_poll_ns = 0;
 230         init_waitqueue_head(&vcpu->wq);
 231         kvm_async_pf_vcpu_init(vcpu);
 232
 233         page = alloc_page(GFP_KERNEL | __GFP_ZERO);
 234         if (!page) {
 235                 r = -ENOMEM;
 236                 goto fail;
 237         }
 238         vcpu->run = page_address(page);
 239
 240         kvm_vcpu_set_in_spin_loop(vcpu, false);
 241         kvm_vcpu_set_dy_eligible(vcpu, false);
 242         vcpu->preempted = false;
 243
 244         r = kvm_arch_vcpu_init(vcpu);
 245         if (r < 0)
 246                 goto fail_free_run;
 247         return 0;
 248
 249 fail_free_run:
 250         free_page((unsigned long)vcpu->run);
 251 fail:
 252         return r;
 253 }
 254 EXPORT_SYMBOL_GPL(kvm_vcpu_init);
 255
 256 void kvm_vcpu_uninit(struct kvm_vcpu *vcpu)
 257 {
 258         put_pid(vcpu->pid);
 259         kvm_arch_vcpu_uninit(vcpu);
 260         free_page((unsigned long)vcpu->run);
 261 }
 262 EXPORT_SYMBOL_GPL(kvm_vcpu_uninit);
 263
 264 #if defined(CONFIG_MMU_NOTIFIER) && defined(KVM_ARCH_WANT_MMU_NOTIFIER)
 265 static inline struct kvm *mmu_notifier_to_kvm(struct mmu_notifier *mn)
 266 {
 267         return container_of(mn, struct kvm, mmu_notifier);
 268 }
 269
 270 static void kvm_mmu_notifier_invalidate_page(struct mmu_notifier *mn,
 271                                              struct mm_struct *mm,
 272                                              unsigned long address)
 273 {
 274         struct kvm *kvm = mmu_notifier_to_kvm(mn);
 275         int need_tlb_flush, idx;
 276
 277         /*
 278          * When ->invalidate_page runs, the linux pte has been zapped
 279          * already but the page is still allocated until
 280          * ->invalidate_page returns. So if we increase the sequence
 281          * here the kvm page fault will notice if the spte can't be
 282          * established because the page is going to be freed. If
 283          * instead the kvm page fault establishes the spte before
 284          * ->invalidate_page runs, kvm_unmap_hva will release it
 285          * before returning.
 286          *
 287          * The sequence increase only need to be seen at spin_unlock
 288          * time, and not at spin_lock time.
 289          *
 290          * Increasing the sequence after the spin_unlock would be
 291          * unsafe because the kvm page fault could then establish the
 292          * pte after kvm_unmap_hva returned, without noticing the page
 293          * is going to be freed.
 294          */
 295         idx = srcu_read_lock(&kvm->srcu);
 296         spin_lock(&kvm->mmu_lock);
 297
 298         kvm->mmu_notifier_seq++;
 299         need_tlb_flush = kvm_unmap_hva(kvm, address) | kvm->tlbs_dirty;
 300         /* we've to flush the tlb before the pages can be freed */
 301         if (need_tlb_flush)
 302                 kvm_flush_remote_tlbs(kvm);
 303
 304         spin_unlock(&kvm->mmu_lock);
 305
 306         kvm_arch_mmu_notifier_invalidate_page(kvm, address);
 307
 308         srcu_read_unlock(&kvm->srcu, idx);
 309 }
 310
 311 static void kvm_mmu_notifier_change_pte(struct mmu_notifier *mn,
 312                                         struct mm_struct *mm,
 313                                         unsigned long address,
 314                                         pte_t pte)
 315 {
 316         struct kvm *kvm = mmu_notifier_to_kvm(mn);
 317         int idx;
 318
 319         idx = srcu_read_lock(&kvm->srcu);
 320         spin_lock(&kvm->mmu_lock);
 321         kvm->mmu_notifier_seq++;
 322         kvm_set_spte_hva(kvm, address, pte);
 323         spin_unlock(&kvm->mmu_lock);
 324         srcu_read_unlock(&kvm->srcu, idx);
 325 }
 326
 327 static void kvm_mmu_notifier_invalidate_range_start(struct mmu_notifier *mn,
 328                                                     struct mm_struct *mm,
 329                                                     unsigned long start,
 330                                                     unsigned long end)
 331 {
 332         struct kvm *kvm = mmu_notifier_to_kvm(mn);
 333         int need_tlb_flush = 0, idx;
 334
 335         idx = srcu_read_lock(&kvm->srcu);
 336         spin_lock(&kvm->mmu_lock);
 337         /*
 338          * The count increase must become visible at unlock time as no
 339          * spte can be established without taking the mmu_lock and
 340          * count is also read inside the mmu_lock critical section.
 341          */
 342         kvm->mmu_notifier_count++;
 343         need_tlb_flush = kvm_unmap_hva_range(kvm, start, end);
 344         need_tlb_flush |= kvm->tlbs_dirty;
 345         /* we've to flush the tlb before the pages can be freed */
 346         if (need_tlb_flush)
 347                 kvm_flush_remote_tlbs(kvm);
 348
 349         spin_unlock(&kvm->mmu_lock);
 350         srcu_read_unlock(&kvm->srcu, idx);
 351 }
 352
 353 static void kvm_mmu_notifier_invalidate_range_end(struct mmu_notifier *mn,
 354                                                   struct mm_struct *mm,
 355                                                   unsigned long start,
 356                                                   unsigned long end)
 357 {
 358         struct kvm *kvm = mmu_notifier_to_kvm(mn);
 359
 360         spin_lock(&kvm->mmu_lock);
 361         /*
 362          * This sequence increase will notify the kvm page fault that
 363          * the page that is going to be mapped in the spte could have
 364          * been freed.
 365          */
 366         kvm->mmu_notifier_seq++;
 367         smp_wmb();
 368         /*
 369          * The above sequence increase must be visible before the
 370          * below count decrease, which is ensured by the smp_wmb above
 371          * in conjunction with the smp_rmb in mmu_notifier_retry().
 372          */
 373         kvm->mmu_notifier_count--;
 374         spin_unlock(&kvm->mmu_lock);
 375
 376         BUG_ON(kvm->mmu_notifier_count < 0);
 377 }
 378
 379 static int kvm_mmu_notifier_clear_flush_young(struct mmu_notifier *mn,
 380                                               struct mm_struct *mm,
 381                                               unsigned long start,
 382                                               unsigned long end)
 383 {
 384         struct kvm *kvm = mmu_notifier_to_kvm(mn);
 385         int young, idx;
 386
 387         idx = srcu_read_lock(&kvm->srcu);
 388         spin_lock(&kvm->mmu_lock);
 389
 390         young = kvm_age_hva(kvm, start, end);
 391         if (young)
 392                 kvm_flush_remote_tlbs(kvm);
 393
 394         spin_unlock(&kvm->mmu_lock);
 395         srcu_read_unlock(&kvm->srcu, idx);
 396
 397         return young;
 398 }
 399
 400 static int kvm_mmu_notifier_clear_young(struct mmu_notifier *mn,
 401                                         struct mm_struct *mm,
 402                                         unsigned long start,
 403                                         unsigned long end)
 404 {
 405         struct kvm *kvm = mmu_notifier_to_kvm(mn);
 406         int young, idx;
 407
 408         idx = srcu_read_lock(&kvm->srcu);
 409         spin_lock(&kvm->mmu_lock);
 410         /*
 411          * Even though we do not flush TLB, this will still adversely
 412          * affect performance on pre-Haswell Intel EPT, where there is
 413          * no EPT Access Bit to clear so that we have to tear down EPT
 414          * tables instead. If we find this unacceptable, we can always
 415          * add a parameter to kvm_age_hva so that it effectively doesn't
 416          * do anything on clear_young.
 417          *
 418          * Also note that currently we never issue secondary TLB flushes
 419          * from clear_young, leaving this job up to the regular system
 420          * cadence. If we find this inaccurate, we might come up with a
 421          * more sophisticated heuristic later.
 422          */
 423         young = kvm_age_hva(kvm, start, end);
 424         spin_unlock(&kvm->mmu_lock);
 425         srcu_read_unlock(&kvm->srcu, idx);
 426
 427         return young;
 428 }
 429
 430 static int kvm_mmu_notifier_test_young(struct mmu_notifier *mn,
 431                                        struct mm_struct *mm,
 432                                        unsigned long address)
 433 {
 434         struct kvm *kvm = mmu_notifier_to_kvm(mn);
 435         int young, idx;
 436
 437         idx = srcu_read_lock(&kvm->srcu);
 438         spin_lock(&kvm->mmu_lock);
 439         young = kvm_test_age_hva(kvm, address);
 440         spin_unlock(&kvm->mmu_lock);
 441         srcu_read_unlock(&kvm->srcu, idx);
 442
 443         return young;
 444 }
 445
 446 static void kvm_mmu_notifier_release(struct mmu_notifier *mn,
 447                                      struct mm_struct *mm)
 448 {
 449         struct kvm *kvm = mmu_notifier_to_kvm(mn);
 450         int idx;
 451
 452         idx = srcu_read_lock(&kvm->srcu);
 453         kvm_arch_flush_shadow_all(kvm);
 454         srcu_read_unlock(&kvm->srcu, idx);
 455 }
 456
 457 static const struct mmu_notifier_ops kvm_mmu_notifier_ops = {
 458         .invalidate_page        = kvm_mmu_notifier_invalidate_page,
 459         .invalidate_range_start = kvm_mmu_notifier_invalidate_range_start,
 460         .invalidate_range_end   = kvm_mmu_notifier_invalidate_range_end,
 461         .clear_flush_young      = kvm_mmu_notifier_clear_flush_young,
 462         .clear_young            = kvm_mmu_notifier_clear_young,
 463         .test_young             = kvm_mmu_notifier_test_young,
 464         .change_pte             = kvm_mmu_notifier_change_pte,
 465         .release                = kvm_mmu_notifier_release,
 466 };
 467
 468 static int kvm_init_mmu_notifier(struct kvm *kvm)
 469 {
 470         kvm->mmu_notifier.ops = &kvm_mmu_notifier_ops;
 471         return mmu_notifier_register(&kvm->mmu_notifier, current->mm);
 472 }
 473
 474 #else  /* !(CONFIG_MMU_NOTIFIER && KVM_ARCH_WANT_MMU_NOTIFIER) */
 475
 476 static int kvm_init_mmu_notifier(struct kvm *kvm)
 477 {
 478         return 0;
 479 }
 480
 481 #endif /* CONFIG_MMU_NOTIFIER && KVM_ARCH_WANT_MMU_NOTIFIER */
 482
 483 static struct kvm_memslots *kvm_alloc_memslots(void)
 484 {
 485         int i;
 486         struct kvm_memslots *slots;
 487
 488         slots = kvm_kvzalloc(sizeof(struct kvm_memslots));
 489         if (!slots)
 490                 return NULL;
 491
 492         /*
 493          * Init kvm generation close to the maximum to easily test the
 494          * code of handling generation number wrap-around.
 495          */
 496         slots->generation = -150;
 497         for (i = 0; i < KVM_MEM_SLOTS_NUM; i++)
 498                 slots->id_to_index[i] = slots->memslots[i].id = i;
 499
 500         return slots;
 501 }
 502
 503 static void kvm_destroy_dirty_bitmap(struct kvm_memory_slot *memslot)
 504 {
 505         if (!memslot->dirty_bitmap)
 506                 return;
 507
 508         kvfree(memslot->dirty_bitmap);
 509         memslot->dirty_bitmap = NULL;
 510 }
 511
 512 /*
 513  * Free any memory in @free but not in @dont.
 514  */
 515 static void kvm_free_memslot(struct kvm *kvm, struct kvm_memory_slot *free,
 516                               struct kvm_memory_slot *dont)
 517 {
 518         if (!dont || free->dirty_bitmap != dont->dirty_bitmap)
 519                 kvm_destroy_dirty_bitmap(free);
 520
 521         kvm_arch_free_memslot(kvm, free, dont);
 522
 523         free->npages = 0;
 524 }
 525
 526 static void kvm_free_memslots(struct kvm *kvm, struct kvm_memslots *slots)
 527 {
 528         struct kvm_memory_slot *memslot;
 529
 530         if (!slots)
 531                 return;
 532
 533         kvm_for_each_memslot(memslot, slots)
 534                 kvm_free_memslot(kvm, memslot, NULL);
 535
 536         kvfree(slots);
 537 }
 538
 539 static struct kvm *kvm_create_vm(unsigned long type)
 540 {
 541         int r, i;
 542         struct kvm *kvm = kvm_arch_alloc_vm();
 543
 544         if (!kvm)
 545                 return ERR_PTR(-ENOMEM);
 546
 547         r = kvm_arch_init_vm(kvm, type);
 548         if (r)
 549                 goto out_err_no_disable;
 550
 551         r = hardware_enable_all();
 552         if (r)
 553                 goto out_err_no_disable;
 554
 555 #ifdef CONFIG_HAVE_KVM_IRQFD
 556         INIT_HLIST_HEAD(&kvm->irq_ack_notifier_list);
 557 #endif
 558
 559         BUILD_BUG_ON(KVM_MEM_SLOTS_NUM > SHRT_MAX);
 560
 561         r = -ENOMEM;
 562         for (i = 0; i < KVM_ADDRESS_SPACE_NUM; i++) {
 563                 kvm->memslots[i] = kvm_alloc_memslots();
 564                 if (!kvm->memslots[i])
 565                         goto out_err_no_srcu;
 566         }
 567
 568         if (init_srcu_struct(&kvm->srcu))
 569                 goto out_err_no_srcu;
 570         if (init_srcu_struct(&kvm->irq_srcu))
 571                 goto out_err_no_irq_srcu;
 572         for (i = 0; i < KVM_NR_BUSES; i++) {
 573                 kvm->buses[i] = kzalloc(sizeof(struct kvm_io_bus),
 574                                         GFP_KERNEL);
 575                 if (!kvm->buses[i])
 576                         goto out_err;
 577         }
 578
 579         spin_lock_init(&kvm->mmu_lock);
 580         kvm->mm = current->mm;
 581         atomic_inc(&kvm->mm->mm_count);
 582         kvm_eventfd_init(kvm);
 583         mutex_init(&kvm->lock);
 584         mutex_init(&kvm->irq_lock);
 585         mutex_init(&kvm->slots_lock);
 586         atomic_set(&kvm->users_count, 1);
 587         INIT_LIST_HEAD(&kvm->devices);
 588
 589         r = kvm_init_mmu_notifier(kvm);
 590         if (r)
 591                 goto out_err;
 592
 593         spin_lock(&kvm_lock);
 594         list_add(&kvm->vm_list, &vm_list);
 595         spin_unlock(&kvm_lock);
 596
 597         preempt_notifier_inc();
 598
 599         return kvm;
 600
 601 out_err:
 602         cleanup_srcu_struct(&kvm->irq_srcu);
 603 out_err_no_irq_srcu:
 604         cleanup_srcu_struct(&kvm->srcu);
 605 out_err_no_srcu:
 606         hardware_disable_all();
 607 out_err_no_disable:
 608         for (i = 0; i < KVM_NR_BUSES; i++)
 609                 kfree(kvm->buses[i]);
 610         for (i = 0; i < KVM_ADDRESS_SPACE_NUM; i++)
 611                 kvm_free_memslots(kvm, kvm->memslots[i]);
 612         kvm_arch_free_vm(kvm);
 613         return ERR_PTR(r);
 614 }
 615
 616 /*
 617  * Avoid using vmalloc for a small buffer.
 618  * Should not be used when the size is statically known.
 619  */
 620 void *kvm_kvzalloc(unsigned long size)
 621 {
 622         if (size > PAGE_SIZE)
 623                 return vzalloc(size);
 624         else
 625                 return kzalloc(size, GFP_KERNEL);
 626 }
 627
 628 static void kvm_destroy_devices(struct kvm *kvm)
 629 {
 630         struct list_head *node, *tmp;
 631
 632         list_for_each_safe(node, tmp, &kvm->devices) {
 633                 struct kvm_device *dev =
 634                         list_entry(node, struct kvm_device, vm_node);
 635
 636                 list_del(node);
 637                 dev->ops->destroy(dev);
 638         }
 639 }
 640
 641 static void kvm_destroy_vm(struct kvm *kvm)
 642 {
 643         int i;
 644         struct mm_struct *mm = kvm->mm;
 645
 646         kvm_arch_sync_events(kvm);
 647         spin_lock(&kvm_lock);
 648         list_del(&kvm->vm_list);
 649         spin_unlock(&kvm_lock);
 650         kvm_free_irq_routing(kvm);
 651         for (i = 0; i < KVM_NR_BUSES; i++)
 652                 kvm_io_bus_destroy(kvm->buses[i]);
 653         kvm_coalesced_mmio_free(kvm);
 654 #if defined(CONFIG_MMU_NOTIFIER) && defined(KVM_ARCH_WANT_MMU_NOTIFIER)
 655         mmu_notifier_unregister(&kvm->mmu_notifier, kvm->mm);
 656 #else
 657         kvm_arch_flush_shadow_all(kvm);
 658 #endif
 659         kvm_arch_destroy_vm(kvm);
 660         kvm_destroy_devices(kvm);
 661         for (i = 0; i < KVM_ADDRESS_SPACE_NUM; i++)
 662                 kvm_free_memslots(kvm, kvm->memslots[i]);
 663         cleanup_srcu_struct(&kvm->irq_srcu);
 664         cleanup_srcu_struct(&kvm->srcu);
 665         kvm_arch_free_vm(kvm);
 666         preempt_notifier_dec();
 667         hardware_disable_all();
 668         mmdrop(mm);
 669 }
 670
 671 void kvm_get_kvm(struct kvm *kvm)
 672 {
 673         atomic_inc(&kvm->users_count);
 674 }
 675 EXPORT_SYMBOL_GPL(kvm_get_kvm);
 676
 677 void kvm_put_kvm(struct kvm *kvm)
 678 {
 679         if (atomic_dec_and_test(&kvm->users_count))
 680                 kvm_destroy_vm(kvm);
 681 }
 682 EXPORT_SYMBOL_GPL(kvm_put_kvm);
 683
 684
 685 static int kvm_vm_release(struct inode *inode, struct file *filp)
 686 {
 687         struct kvm *kvm = filp->private_data;
 688
 689         kvm_irqfd_release(kvm);
 690
 691         kvm_put_kvm(kvm);
 692         return 0;
 693 }
 694
 695 /*
 696  * Allocation size is twice as large as the actual dirty bitmap size.
 697  * See x86's kvm_vm_ioctl_get_dirty_log() why this is needed.
 698  */
 699 static int kvm_create_dirty_bitmap(struct kvm_memory_slot *memslot)
 700 {
 701         unsigned long dirty_bytes = 2 * kvm_dirty_bitmap_bytes(memslot);
 702
 703         memslot->dirty_bitmap = kvm_kvzalloc(dirty_bytes);
 704         if (!memslot->dirty_bitmap)
 705                 return -ENOMEM;
 706
 707         return 0;
 708 }
 709
 710 /*
 711  * Insert memslot and re-sort memslots based on their GFN,
 712  * so binary search could be used to lookup GFN.
 713  * Sorting algorithm takes advantage of having initially
 714  * sorted array and known changed memslot position.
 715  */
 716 static void update_memslots(struct kvm_memslots *slots,
 717                             struct kvm_memory_slot *new)
 718 {
 719         int id = new->id;
 720         int i = slots->id_to_index[id];
 721         struct kvm_memory_slot *mslots = slots->memslots;
 722
 723         WARN_ON(mslots[i].id != id);
 724         if (!new->npages) {
 725                 WARN_ON(!mslots[i].npages);
 726                 if (mslots[i].npages)
 727                         slots->used_slots--;
 728         } else {
 729                 if (!mslots[i].npages)
 730                         slots->used_slots++;
 731         }
 732
 733         while (i < KVM_MEM_SLOTS_NUM - 1 &&
 734                new->base_gfn <= mslots[i + 1].base_gfn) {
 735                 if (!mslots[i + 1].npages)
 736                         break;
 737                 mslots[i] = mslots[i + 1];
 738                 slots->id_to_index[mslots[i].id] = i;
 739                 i++;
 740         }
 741
 742         /*
 743          * The ">=" is needed when creating a slot with base_gfn == 0,
 744          * so that it moves before all those with base_gfn == npages == 0.
 745          *
 746          * On the other hand, if new->npages is zero, the above loop has
 747          * already left i pointing to the beginning of the empty part of
 748          * mslots, and the ">=" would move the hole backwards in this
 749          * case---which is wrong.  So skip the loop when deleting a slot.
 750          */
 751         if (new->npages) {
 752                 while (i > 0 &&
 753                        new->base_gfn >= mslots[i - 1].base_gfn) {
 754                         mslots[i] = mslots[i - 1];
 755                         slots->id_to_index[mslots[i].id] = i;
 756                         i--;
 757                 }
 758         } else
 759                 WARN_ON_ONCE(i != slots->used_slots);
 760
 761         mslots[i] = *new;
 762         slots->id_to_index[mslots[i].id] = i;
 763 }
 764
 765 static int check_memory_region_flags(const struct kvm_userspace_memory_region *mem)
 766 {
 767         u32 valid_flags = KVM_MEM_LOG_DIRTY_PAGES;
 768
 769 #ifdef __KVM_HAVE_READONLY_MEM
 770         valid_flags |= KVM_MEM_READONLY;
 771 #endif
 772
 773         if (mem->flags & ~valid_flags)
 774                 return -EINVAL;
 775
 776         return 0;
 777 }
 778
 779 static struct kvm_memslots *install_new_memslots(struct kvm *kvm,
 780                 int as_id, struct kvm_memslots *slots)
 781 {
 782         struct kvm_memslots *old_memslots = __kvm_memslots(kvm, as_id);
 783
 784         /*
 785          * Set the low bit in the generation, which disables SPTE caching
 786          * until the end of synchronize_srcu_expedited.
 787          */
 788         WARN_ON(old_memslots->generation & 1);
 789         slots->generation = old_memslots->generation + 1;
 790
 791         rcu_assign_pointer(kvm->memslots[as_id], slots);
 792         synchronize_srcu_expedited(&kvm->srcu);
 793
 794         /*
 795          * Increment the new memslot generation a second time. This prevents
 796          * vm exits that race with memslot updates from caching a memslot
 797          * generation that will (potentially) be valid forever.
 798          */
 799         slots->generation++;
 800
 801         kvm_arch_memslots_updated(kvm, slots);
 802
 803         return old_memslots;
 804 }
 805
 806 /*
 807  * Allocate some memory and give it an address in the guest physical address
 808  * space.
 809  *
 810  * Discontiguous memory is allowed, mostly for framebuffers.
 811  *
 812  * Must be called holding kvm->slots_lock for write.
 813  */
 814 int __kvm_set_memory_region(struct kvm *kvm,
 815                             const struct kvm_userspace_memory_region *mem)
 816 {
 817         int r;
 818         gfn_t base_gfn;
 819         unsigned long npages;
 820         struct kvm_memory_slot *slot;
 821         struct kvm_memory_slot old, new;
 822         struct kvm_memslots *slots = NULL, *old_memslots;
 823         int as_id, id;
 824         enum kvm_mr_change change;
 825
 826         r = check_memory_region_flags(mem);
 827         if (r)
 828                 goto out;
 829
 830         r = -EINVAL;
 831         as_id = mem->slot >> 16;
 832         id = (u16)mem->slot;
 833
 834         /* General sanity checks */
 835         if (mem->memory_size & (PAGE_SIZE - 1))
 836                 goto out;
 837         if (mem->guest_phys_addr & (PAGE_SIZE - 1))
 838                 goto out;
 839         /* We can read the guest memory with __xxx_user() later on. */
 840         if ((id < KVM_USER_MEM_SLOTS) &&
 841             ((mem->userspace_addr & (PAGE_SIZE - 1)) ||
 842              !access_ok(VERIFY_WRITE,
 843                         (void __user *)(unsigned long)mem->userspace_addr,
 844                         mem->memory_size)))
 845                 goto out;
 846         if (as_id >= KVM_ADDRESS_SPACE_NUM || id >= KVM_MEM_SLOTS_NUM)
 847                 goto out;
 848         if (mem->guest_phys_addr + mem->memory_size < mem->guest_phys_addr)
 849                 goto out;
 850
 851         slot = id_to_memslot(__kvm_memslots(kvm, as_id), id);
 852         base_gfn = mem->guest_phys_addr >> PAGE_SHIFT;
 853         npages = mem->memory_size >> PAGE_SHIFT;
 854
 855         if (npages > KVM_MEM_MAX_NR_PAGES)
 856                 goto out;
 857
 858         new = old = *slot;
 859
 860         new.id = id;
 861         new.base_gfn = base_gfn;
 862         new.npages = npages;
 863         new.flags = mem->flags;
 864
 865         if (npages) {
 866                 if (!old.npages)
 867                         change = KVM_MR_CREATE;
 868                 else { /* Modify an existing slot. */
 869                         if ((mem->userspace_addr != old.userspace_addr) ||
 870                             (npages != old.npages) ||
 871                             ((new.flags ^ old.flags) & KVM_MEM_READONLY))
 872                                 goto out;
 873
 874                         if (base_gfn != old.base_gfn)
 875                                 change = KVM_MR_MOVE;
 876                         else if (new.flags != old.flags)
 877                                 change = KVM_MR_FLAGS_ONLY;
 878                         else { /* Nothing to change. */
 879                                 r = 0;
 880                                 goto out;
 881                         }
 882                 }
 883         } else {
 884                 if (!old.npages)
 885                         goto out;
 886
 887                 change = KVM_MR_DELETE;
 888                 new.base_gfn = 0;
 889                 new.flags = 0;
 890         }
 891
 892         if ((change == KVM_MR_CREATE) || (change == KVM_MR_MOVE)) {
 893                 /* Check for overlaps */
 894                 r = -EEXIST;
 895                 kvm_for_each_memslot(slot, __kvm_memslots(kvm, as_id)) {
 896                         if ((slot->id >= KVM_USER_MEM_SLOTS) ||
 897                             (slot->id == id))
 898                                 continue;
 899                         if (!((base_gfn + npages <= slot->base_gfn) ||
 900                               (base_gfn >= slot->base_gfn + slot->npages)))
 901                                 goto out;
 902                 }
 903         }
 904
 905         /* Free page dirty bitmap if unneeded */
 906         if (!(new.flags & KVM_MEM_LOG_DIRTY_PAGES))
 907                 new.dirty_bitmap = NULL;
 908
 909         r = -ENOMEM;
 910         if (change == KVM_MR_CREATE) {
 911                 new.userspace_addr = mem->userspace_addr;
 912
 913                 if (kvm_arch_create_memslot(kvm, &new, npages))
 914                         goto out_free;
 915         }
 916
 917         /* Allocate page dirty bitmap if needed */
 918         if ((new.flags & KVM_MEM_LOG_DIRTY_PAGES) && !new.dirty_bitmap) {
 919                 if (kvm_create_dirty_bitmap(&new) < 0)
 920                         goto out_free;
 921         }
 922
 923         slots = kvm_kvzalloc(sizeof(struct kvm_memslots));
 924         if (!slots)
 925                 goto out_free;
 926         memcpy(slots, __kvm_memslots(kvm, as_id), sizeof(struct kvm_memslots));
 927
 928         if ((change == KVM_MR_DELETE) || (change == KVM_MR_MOVE)) {
 929                 slot = id_to_memslot(slots, id);
 930                 slot->flags |= KVM_MEMSLOT_INVALID;
 931
 932                 old_memslots = install_new_memslots(kvm, as_id, slots);
 933
 934                 /* slot was deleted or moved, clear iommu mapping */
 935                 kvm_iommu_unmap_pages(kvm, &old);
 936                 /* From this point no new shadow pages pointing to a deleted,
 937                  * or moved, memslot will be created.
 938                  *
 939                  * validation of sp->gfn happens in:
 940                  *      - gfn_to_hva (kvm_read_guest, gfn_to_pfn)
 941                  *      - kvm_is_visible_gfn (mmu_check_roots)
 942                  */
 943                 kvm_arch_flush_shadow_memslot(kvm, slot);
 944
 945                 /*
 946                  * We can re-use the old_memslots from above, the only difference
 947                  * from the currently installed memslots is the invalid flag.  This
 948                  * will get overwritten by update_memslots anyway.
 949                  */
 950                 slots = old_memslots;
 951         }
 952
 953         r = kvm_arch_prepare_memory_region(kvm, &new, mem, change);
 954         if (r)
 955                 goto out_slots;
 956
 957         /* actual memory is freed via old in kvm_free_memslot below */
 958         if (change == KVM_MR_DELETE) {
 959                 new.dirty_bitmap = NULL;
 960                 memset(&new.arch, 0, sizeof(new.arch));
 961         }
 962
 963         update_memslots(slots, &new);
 964         old_memslots = install_new_memslots(kvm, as_id, slots);
 965
 966         kvm_arch_commit_memory_region(kvm, mem, &old, &new, change);
 967
 968         kvm_free_memslot(kvm, &old, &new);
 969         kvfree(old_memslots);
 970
 971         /*
 972          * IOMMU mapping:  New slots need to be mapped.  Old slots need to be
 973          * un-mapped and re-mapped if their base changes.  Since base change
 974          * unmapping is handled above with slot deletion, mapping alone is
 975          * needed here.  Anything else the iommu might care about for existing
 976          * slots (size changes, userspace addr changes and read-only flag
 977          * changes) is disallowed above, so any other attribute changes getting
 978          * here can be skipped.
 979          */
 980         if ((change == KVM_MR_CREATE) || (change == KVM_MR_MOVE)) {
 981                 r = kvm_iommu_map_pages(kvm, &new);
 982                 return r;
 983         }
 984
 985         return 0;
 986
 987 out_slots:
 988         kvfree(slots);
 989 out_free:
 990         kvm_free_memslot(kvm, &new, &old);
 991 out:
 992         return r;
 993 }
 994 EXPORT_SYMBOL_GPL(__kvm_set_memory_region);
 995
 996 int kvm_set_memory_region(struct kvm *kvm,
 997                           const struct kvm_userspace_memory_region *mem)
 998 {
 999         int r;
1000
1001         mutex_lock(&kvm->slots_lock);
1002         r = __kvm_set_memory_region(kvm, mem);
1003         mutex_unlock(&kvm->slots_lock);
1004         return r;
1005 }
1006 EXPORT_SYMBOL_GPL(kvm_set_memory_region);
1007
1008 static int kvm_vm_ioctl_set_memory_region(struct kvm *kvm,
1009                                           struct kvm_userspace_memory_region *mem)
1010 {
1011         if ((u16)mem->slot >= KVM_USER_MEM_SLOTS)
1012                 return -EINVAL;
1013
1014         return kvm_set_memory_region(kvm, mem);
1015 }
1016
1017 int kvm_get_dirty_log(struct kvm *kvm,
1018                         struct kvm_dirty_log *log, int *is_dirty)
1019 {
1020         struct kvm_memslots *slots;
1021         struct kvm_memory_slot *memslot;
1022         int r, i, as_id, id;
1023         unsigned long n;
1024         unsigned long any = 0;
1025
1026         r = -EINVAL;
1027         as_id = log->slot >> 16;
1028         id = (u16)log->slot;
1029         if (as_id >= KVM_ADDRESS_SPACE_NUM || id >= KVM_USER_MEM_SLOTS)
1030                 goto out;
1031
1032         slots = __kvm_memslots(kvm, as_id);
1033         memslot = id_to_memslot(slots, id);
1034         r = -ENOENT;
1035         if (!memslot->dirty_bitmap)
1036                 goto out;
1037
1038         n = kvm_dirty_bitmap_bytes(memslot);
1039
1040         for (i = 0; !any && i < n/sizeof(long); ++i)
1041                 any = memslot->dirty_bitmap[i];
1042
1043         r = -EFAULT;
1044         if (copy_to_user(log->dirty_bitmap, memslot->dirty_bitmap, n))
1045                 goto out;
1046
1047         if (any)
1048                 *is_dirty = 1;
1049
1050         r = 0;
1051 out:
1052         return r;
1053 }
1054 EXPORT_SYMBOL_GPL(kvm_get_dirty_log);
1055
1056 #ifdef CONFIG_KVM_GENERIC_DIRTYLOG_READ_PROTECT
1057 /**
1058  * kvm_get_dirty_log_protect - get a snapshot of dirty pages, and if any pages
1059  *      are dirty write protect them for next write.
1060  * @kvm:        pointer to kvm instance
1061  * @log:        slot id and address to which we copy the log
1062  * @is_dirty:   flag set if any page is dirty
1063  *
1064  * We need to keep it in mind that VCPU threads can write to the bitmap
1065  * concurrently. So, to avoid losing track of dirty pages we keep the
1066  * following order:
1067  *
1068  *    1. Take a snapshot of the bit and clear it if needed.
1069  *    2. Write protect the corresponding page.
1070  *    3. Copy the snapshot to the userspace.
1071  *    4. Upon return caller flushes TLB's if needed.
1072  *
1073  * Between 2 and 4, the guest may write to the page using the remaining TLB
1074  * entry.  This is not a problem because the page is reported dirty using
1075  * the snapshot taken before and step 4 ensures that writes done after
1076  * exiting to userspace will be logged for the next call.
1077  *
1078  */
1079 int kvm_get_dirty_log_protect(struct kvm *kvm,
1080                         struct kvm_dirty_log *log, bool *is_dirty)
1081 {
1082         struct kvm_memslots *slots;
1083         struct kvm_memory_slot *memslot;
1084         int r, i, as_id, id;
1085         unsigned long n;
1086         unsigned long *dirty_bitmap;
1087         unsigned long *dirty_bitmap_buffer;
1088
1089         r = -EINVAL;
1090         as_id = log->slot >> 16;
1091         id = (u16)log->slot;
1092         if (as_id >= KVM_ADDRESS_SPACE_NUM || id >= KVM_USER_MEM_SLOTS)
1093                 goto out;
1094
1095         slots = __kvm_memslots(kvm, as_id);
1096         memslot = id_to_memslot(slots, id);
1097
1098         dirty_bitmap = memslot->dirty_bitmap;
1099         r = -ENOENT;
1100         if (!dirty_bitmap)
1101                 goto out;
1102
1103         n = kvm_dirty_bitmap_bytes(memslot);
1104
1105         dirty_bitmap_buffer = dirty_bitmap + n / sizeof(long);
1106         memset(dirty_bitmap_buffer, 0, n);
1107
1108         spin_lock(&kvm->mmu_lock);
1109         *is_dirty = false;
1110         for (i = 0; i < n / sizeof(long); i++) {
1111                 unsigned long mask;
1112                 gfn_t offset;
1113
1114                 if (!dirty_bitmap[i])
1115                         continue;
1116
1117                 *is_dirty = true;
1118
1119                 mask = xchg(&dirty_bitmap[i], 0);
1120                 dirty_bitmap_buffer[i] = mask;
1121
1122                 if (mask) {
1123                         offset = i * BITS_PER_LONG;
1124                         kvm_arch_mmu_enable_log_dirty_pt_masked(kvm, memslot,
1125                                                                 offset, mask);
1126                 }
1127         }
1128
1129         spin_unlock(&kvm->mmu_lock);
1130
1131         r = -EFAULT;
1132         if (copy_to_user(log->dirty_bitmap, dirty_bitmap_buffer, n))
1133                 goto out;
1134
1135         r = 0;
1136 out:
1137         return r;
1138 }
1139 EXPORT_SYMBOL_GPL(kvm_get_dirty_log_protect);
1140 #endif
1141
1142 bool kvm_largepages_enabled(void)
1143 {
1144         return largepages_enabled;
1145 }
1146
1147 void kvm_disable_largepages(void)
1148 {
1149         largepages_enabled = false;
1150 }
1151 EXPORT_SYMBOL_GPL(kvm_disable_largepages);
1152
1153 struct kvm_memory_slot *gfn_to_memslot(struct kvm *kvm, gfn_t gfn)
1154 {
1155         return __gfn_to_memslot(kvm_memslots(kvm), gfn);
1156 }
1157 EXPORT_SYMBOL_GPL(gfn_to_memslot);
1158
1159 struct kvm_memory_slot *kvm_vcpu_gfn_to_memslot(struct kvm_vcpu *vcpu, gfn_t gfn)
1160 {
1161         return __gfn_to_memslot(kvm_vcpu_memslots(vcpu), gfn);
1162 }
1163
1164 int kvm_is_visible_gfn(struct kvm *kvm, gfn_t gfn)
1165 {
1166         struct kvm_memory_slot *memslot = gfn_to_memslot(kvm, gfn);
1167
1168         if (!memslot || memslot->id >= KVM_USER_MEM_SLOTS ||
1169               memslot->flags & KVM_MEMSLOT_INVALID)
1170                 return 0;
1171
1172         return 1;
1173 }
1174 EXPORT_SYMBOL_GPL(kvm_is_visible_gfn);
1175
1176 unsigned long kvm_host_page_size(struct kvm *kvm, gfn_t gfn)
1177 {
1178         struct vm_area_struct *vma;
1179         unsigned long addr, size;
1180
1181         size = PAGE_SIZE;
1182
1183         addr = gfn_to_hva(kvm, gfn);
1184         if (kvm_is_error_hva(addr))
1185                 return PAGE_SIZE;
1186
1187         down_read(&current->mm->mmap_sem);
1188         vma = find_vma(current->mm, addr);
1189         if (!vma)
1190                 goto out;
1191
1192         size = vma_kernel_pagesize(vma);
1193
1194 out:
1195         up_read(&current->mm->mmap_sem);
1196
1197         return size;
1198 }
1199
1200 static bool memslot_is_readonly(struct kvm_memory_slot *slot)
1201 {
1202         return slot->flags & KVM_MEM_READONLY;
1203 }
1204
1205 static unsigned long __gfn_to_hva_many(struct kvm_memory_slot *slot, gfn_t gfn,
1206                                        gfn_t *nr_pages, bool write)
1207 {
1208         if (!slot || slot->flags & KVM_MEMSLOT_INVALID)
1209                 return KVM_HVA_ERR_BAD;
1210
1211         if (memslot_is_readonly(slot) && write)
1212                 return KVM_HVA_ERR_RO_BAD;
1213
1214         if (nr_pages)
1215                 *nr_pages = slot->npages - (gfn - slot->base_gfn);
1216
1217         return __gfn_to_hva_memslot(slot, gfn);
1218 }
1219
1220 static unsigned long gfn_to_hva_many(struct kvm_memory_slot *slot, gfn_t gfn,
1221                                      gfn_t *nr_pages)
1222 {
1223         return __gfn_to_hva_many(slot, gfn, nr_pages, true);
1224 }
1225
1226 unsigned long gfn_to_hva_memslot(struct kvm_memory_slot *slot,
1227                                         gfn_t gfn)
1228 {
1229         return gfn_to_hva_many(slot, gfn, NULL);
1230 }
1231 EXPORT_SYMBOL_GPL(gfn_to_hva_memslot);
1232
1233 unsigned long gfn_to_hva(struct kvm *kvm, gfn_t gfn)
1234 {
1235         return gfn_to_hva_many(gfn_to_memslot(kvm, gfn), gfn, NULL);
1236 }
1237 EXPORT_SYMBOL_GPL(gfn_to_hva);
1238
1239 unsigned long kvm_vcpu_gfn_to_hva(struct kvm_vcpu *vcpu, gfn_t gfn)
1240 {
1241         return gfn_to_hva_many(kvm_vcpu_gfn_to_memslot(vcpu, gfn), gfn, NULL);
1242 }
1243 EXPORT_SYMBOL_GPL(kvm_vcpu_gfn_to_hva);
1244
1245 /*
1246  * If writable is set to false, the hva returned by this function is only
1247  * allowed to be read.
1248  */
1249 unsigned long gfn_to_hva_memslot_prot(struct kvm_memory_slot *slot,
1250                                       gfn_t gfn, bool *writable)
1251 {
1252         unsigned long hva = __gfn_to_hva_many(slot, gfn, NULL, false);
1253
1254         if (!kvm_is_error_hva(hva) && writable)
1255                 *writable = !memslot_is_readonly(slot);
1256
1257         return hva;
1258 }
1259
1260 unsigned long gfn_to_hva_prot(struct kvm *kvm, gfn_t gfn, bool *writable)
1261 {
1262         struct kvm_memory_slot *slot = gfn_to_memslot(kvm, gfn);
1263
1264         return gfn_to_hva_memslot_prot(slot, gfn, writable);
1265 }
1266
1267 unsigned long kvm_vcpu_gfn_to_hva_prot(struct kvm_vcpu *vcpu, gfn_t gfn, bool *writable)
1268 {
1269         struct kvm_memory_slot *slot = kvm_vcpu_gfn_to_memslot(vcpu, gfn);
1270
1271         return gfn_to_hva_memslot_prot(slot, gfn, writable);
1272 }
1273
1274 static int get_user_page_nowait(struct task_struct *tsk, struct mm_struct *mm,
1275         unsigned long start, int write, struct page **page)
1276 {
1277         int flags = FOLL_TOUCH | FOLL_NOWAIT | FOLL_HWPOISON | FOLL_GET;
1278
1279         if (write)
1280                 flags |= FOLL_WRITE;
1281
1282         return __get_user_pages(tsk, mm, start, 1, flags, page, NULL, NULL);
1283 }
1284
1285 static inline int check_user_page_hwpoison(unsigned long addr)
1286 {
1287         int rc, flags = FOLL_TOUCH | FOLL_HWPOISON | FOLL_WRITE;
1288
1289         rc = __get_user_pages(current, current->mm, addr, 1,
1290                               flags, NULL, NULL, NULL);
1291         return rc == -EHWPOISON;
1292 }
1293
1294 /*
1295  * The atomic path to get the writable pfn which will be stored in @pfn,
1296  * true indicates success, otherwise false is returned.
1297  */
1298 static bool hva_to_pfn_fast(unsigned long addr, bool atomic, bool *async,
1299                             bool write_fault, bool *writable, pfn_t *pfn)
1300 {
1301         struct page *page[1];
1302         int npages;
1303
1304         if (!(async || atomic))
1305                 return false;
1306
1307         /*
1308          * Fast pin a writable pfn only if it is a write fault request
1309          * or the caller allows to map a writable pfn for a read fault
1310          * request.
1311          */
1312         if (!(write_fault || writable))
1313                 return false;
1314
1315         npages = __get_user_pages_fast(addr, 1, 1, page);
1316         if (npages == 1) {
1317                 *pfn = page_to_pfn(page[0]);
1318
1319                 if (writable)
1320                         *writable = true;
1321                 return true;
1322         }
1323
1324         return false;
1325 }
1326
1327 /*
1328  * The slow path to get the pfn of the specified host virtual address,
1329  * 1 indicates success, -errno is returned if error is detected.
1330  */
1331 static int hva_to_pfn_slow(unsigned long addr, bool *async, bool write_fault,
1332                            bool *writable, pfn_t *pfn)
1333 {
1334         struct page *page[1];
1335         int npages = 0;
1336
1337         might_sleep();
1338
1339         if (writable)
1340                 *writable = write_fault;
1341
1342         if (async) {
1343                 down_read(&current->mm->mmap_sem);
1344                 npages = get_user_page_nowait(current, current->mm,
1345                                               addr, write_fault, page);
1346                 up_read(&current->mm->mmap_sem);
1347         } else
1348                 npages = __get_user_pages_unlocked(current, current->mm, addr, 1,
1349                                                    write_fault, 0, page,
1350                                                    FOLL_TOUCH|FOLL_HWPOISON);
1351         if (npages != 1)
1352                 return npages;
1353
1354         /* map read fault as writable if possible */
1355         if (unlikely(!write_fault) && writable) {
1356                 struct page *wpage[1];
1357
1358                 npages = __get_user_pages_fast(addr, 1, 1, wpage);
1359                 if (npages == 1) {
1360                         *writable = true;
1361                         put_page(page[0]);
1362                         page[0] = wpage[0];
1363                 }
1364
1365                 npages = 1;
1366         }
1367         *pfn = page_to_pfn(page[0]);
1368         return npages;
1369 }
1370
1371 static bool vma_is_valid(struct vm_area_struct *vma, bool write_fault)
1372 {
1373         if (unlikely(!(vma->vm_flags & VM_READ)))
1374                 return false;
1375
1376         if (write_fault && (unlikely(!(vma->vm_flags & VM_WRITE))))
1377                 return false;
1378
1379         return true;
1380 }
1381
1382 /*
1383  * Pin guest page in memory and return its pfn.
1384  * @addr: host virtual address which maps memory to the guest
1385  * @atomic: whether this function can sleep
1386  * @async: whether this function need to wait IO complete if the
1387  *         host page is not in the memory
1388  * @write_fault: whether we should get a writable host page
1389  * @writable: whether it allows to map a writable host page for !@write_fault
1390  *
1391  * The function will map a writable host page for these two cases:
1392  * 1): @write_fault = true
1393  * 2): @write_fault = false && @writable, @writable will tell the caller
1394  *     whether the mapping is writable.
1395  */
1396 static pfn_t hva_to_pfn(unsigned long addr, bool atomic, bool *async,
1397                         bool write_fault, bool *writable)
1398 {
1399         struct vm_area_struct *vma;
1400         pfn_t pfn = 0;
1401         int npages;
1402
1403         /* we can do it either atomically or asynchronously, not both */
1404         BUG_ON(atomic && async);
1405
1406         if (hva_to_pfn_fast(addr, atomic, async, write_fault, writable, &pfn))
1407                 return pfn;
1408
1409         if (atomic)
1410                 return KVM_PFN_ERR_FAULT;
1411
1412         npages = hva_to_pfn_slow(addr, async, write_fault, writable, &pfn);
1413         if (npages == 1)
1414                 return pfn;
1415
1416         down_read(&current->mm->mmap_sem);
1417         if (npages == -EHWPOISON ||
1418               (!async && check_user_page_hwpoison(addr))) {
1419                 pfn = KVM_PFN_ERR_HWPOISON;
1420                 goto exit;
1421         }
1422
1423         vma = find_vma_intersection(current->mm, addr, addr + 1);
1424
1425         if (vma == NULL)
1426                 pfn = KVM_PFN_ERR_FAULT;
1427         else if ((vma->vm_flags & VM_PFNMAP)) {
1428                 pfn = ((addr - vma->vm_start) >> PAGE_SHIFT) +
1429                         vma->vm_pgoff;
1430                 BUG_ON(!kvm_is_reserved_pfn(pfn));
1431         } else {
1432                 if (async && vma_is_valid(vma, write_fault))
1433                         *async = true;
1434                 pfn = KVM_PFN_ERR_FAULT;
1435         }
1436 exit:
1437         up_read(&current->mm->mmap_sem);
1438         return pfn;
1439 }
1440
1441 pfn_t __gfn_to_pfn_memslot(struct kvm_memory_slot *slot, gfn_t gfn, bool atomic,
1442                            bool *async, bool write_fault, bool *writable)
1443 {
1444         unsigned long addr = __gfn_to_hva_many(slot, gfn, NULL, write_fault);
1445
1446         if (addr == KVM_HVA_ERR_RO_BAD)
1447                 return KVM_PFN_ERR_RO_FAULT;
1448
1449         if (kvm_is_error_hva(addr))
1450                 return KVM_PFN_NOSLOT;
1451
1452         /* Do not map writable pfn in the readonly memslot. */
1453         if (writable && memslot_is_readonly(slot)) {
1454                 *writable = false;
1455                 writable = NULL;
1456         }
1457
1458         return hva_to_pfn(addr, atomic, async, write_fault,
1459                           writable);
1460 }
1461 EXPORT_SYMBOL_GPL(__gfn_to_pfn_memslot);
1462
1463 pfn_t gfn_to_pfn_prot(struct kvm *kvm, gfn_t gfn, bool write_fault,
1464                       bool *writable)
1465 {
1466         return __gfn_to_pfn_memslot(gfn_to_memslot(kvm, gfn), gfn, false, NULL,
1467                                     write_fault, writable);
1468 }
1469 EXPORT_SYMBOL_GPL(gfn_to_pfn_prot);
1470
1471 pfn_t gfn_to_pfn_memslot(struct kvm_memory_slot *slot, gfn_t gfn)
1472 {
1473         return __gfn_to_pfn_memslot(slot, gfn, false, NULL, true, NULL);
1474 }
1475 EXPORT_SYMBOL_GPL(gfn_to_pfn_memslot);
1476
1477 pfn_t gfn_to_pfn_memslot_atomic(struct kvm_memory_slot *slot, gfn_t gfn)
1478 {
1479         return __gfn_to_pfn_memslot(slot, gfn, true, NULL, true, NULL);
1480 }
1481 EXPORT_SYMBOL_GPL(gfn_to_pfn_memslot_atomic);
1482
1483 pfn_t gfn_to_pfn_atomic(struct kvm *kvm, gfn_t gfn)
1484 {
1485         return gfn_to_pfn_memslot_atomic(gfn_to_memslot(kvm, gfn), gfn);
1486 }
1487 EXPORT_SYMBOL_GPL(gfn_to_pfn_atomic);
1488
1489 pfn_t kvm_vcpu_gfn_to_pfn_atomic(struct kvm_vcpu *vcpu, gfn_t gfn)
1490 {
1491         return gfn_to_pfn_memslot_atomic(kvm_vcpu_gfn_to_memslot(vcpu, gfn), gfn);
1492 }
1493 EXPORT_SYMBOL_GPL(kvm_vcpu_gfn_to_pfn_atomic);
1494
1495 pfn_t gfn_to_pfn(struct kvm *kvm, gfn_t gfn)
1496 {
1497         return gfn_to_pfn_memslot(gfn_to_memslot(kvm, gfn), gfn);
1498 }
1499 EXPORT_SYMBOL_GPL(gfn_to_pfn);
1500
1501 pfn_t kvm_vcpu_gfn_to_pfn(struct kvm_vcpu *vcpu, gfn_t gfn)
1502 {
1503         return gfn_to_pfn_memslot(kvm_vcpu_gfn_to_memslot(vcpu, gfn), gfn);
1504 }
1505 EXPORT_SYMBOL_GPL(kvm_vcpu_gfn_to_pfn);
1506
1507 int gfn_to_page_many_atomic(struct kvm_memory_slot *slot, gfn_t gfn,
1508                             struct page **pages, int nr_pages)
1509 {
1510         unsigned long addr;
1511         gfn_t entry;
1512
1513         addr = gfn_to_hva_many(slot, gfn, &entry);
1514         if (kvm_is_error_hva(addr))
1515                 return -1;
1516
1517         if (entry < nr_pages)
1518                 return 0;
1519
1520         return __get_user_pages_fast(addr, nr_pages, 1, pages);
1521 }
1522 EXPORT_SYMBOL_GPL(gfn_to_page_many_atomic);
1523
1524 static struct page *kvm_pfn_to_page(pfn_t pfn)
1525 {
1526         if (is_error_noslot_pfn(pfn))
1527                 return KVM_ERR_PTR_BAD_PAGE;
1528
1529         if (kvm_is_reserved_pfn(pfn)) {
1530                 WARN_ON(1);
1531                 return KVM_ERR_PTR_BAD_PAGE;
1532         }
1533
1534         return pfn_to_page(pfn);
1535 }
1536
1537 struct page *gfn_to_page(struct kvm *kvm, gfn_t gfn)
1538 {
1539         pfn_t pfn;
1540
1541         pfn = gfn_to_pfn(kvm, gfn);
1542
1543         return kvm_pfn_to_page(pfn);
1544 }
1545 EXPORT_SYMBOL_GPL(gfn_to_page);
1546
1547 struct page *kvm_vcpu_gfn_to_page(struct kvm_vcpu *vcpu, gfn_t gfn)
1548 {
1549         pfn_t pfn;
1550
1551         pfn = kvm_vcpu_gfn_to_pfn(vcpu, gfn);
1552
1553         return kvm_pfn_to_page(pfn);
1554 }
1555 EXPORT_SYMBOL_GPL(kvm_vcpu_gfn_to_page);
1556
1557 void kvm_release_page_clean(struct page *page)
1558 {
1559         WARN_ON(is_error_page(page));
1560
1561         kvm_release_pfn_clean(page_to_pfn(page));
1562 }
1563 EXPORT_SYMBOL_GPL(kvm_release_page_clean);
1564
1565 void kvm_release_pfn_clean(pfn_t pfn)
1566 {
1567         if (!is_error_noslot_pfn(pfn) && !kvm_is_reserved_pfn(pfn))
1568                 put_page(pfn_to_page(pfn));
1569 }
1570 EXPORT_SYMBOL_GPL(kvm_release_pfn_clean);
1571
1572 void kvm_release_page_dirty(struct page *page)
1573 {
1574         WARN_ON(is_error_page(page));
1575
1576         kvm_release_pfn_dirty(page_to_pfn(page));
1577 }
1578 EXPORT_SYMBOL_GPL(kvm_release_page_dirty);
1579
1580 static void kvm_release_pfn_dirty(pfn_t pfn)
1581 {
1582         kvm_set_pfn_dirty(pfn);
1583         kvm_release_pfn_clean(pfn);
1584 }
1585
1586 void kvm_set_pfn_dirty(pfn_t pfn)
1587 {
1588         if (!kvm_is_reserved_pfn(pfn)) {
1589                 struct page *page = pfn_to_page(pfn);
1590
1591                 if (!PageReserved(page))
1592                         SetPageDirty(page);
1593         }
1594 }
1595 EXPORT_SYMBOL_GPL(kvm_set_pfn_dirty);
1596
1597 void kvm_set_pfn_accessed(pfn_t pfn)
1598 {
1599         if (!kvm_is_reserved_pfn(pfn))
1600                 mark_page_accessed(pfn_to_page(pfn));
1601 }
1602 EXPORT_SYMBOL_GPL(kvm_set_pfn_accessed);
1603
1604 void kvm_get_pfn(pfn_t pfn)
1605 {
1606         if (!kvm_is_reserved_pfn(pfn))
1607                 get_page(pfn_to_page(pfn));
1608 }
1609 EXPORT_SYMBOL_GPL(kvm_get_pfn);
1610
1611 static int next_segment(unsigned long len, int offset)
1612 {
1613         if (len > PAGE_SIZE - offset)
1614                 return PAGE_SIZE - offset;
1615         else
1616                 return len;
1617 }
1618
1619 static int __kvm_read_guest_page(struct kvm_memory_slot *slot, gfn_t gfn,
1620                                  void *data, int offset, int len)
1621 {
1622         int r;
1623         unsigned long addr;
1624
1625         addr = gfn_to_hva_memslot_prot(slot, gfn, NULL);
1626         if (kvm_is_error_hva(addr))
1627                 return -EFAULT;
1628         r = __copy_from_user(data, (void __user *)addr + offset, len);
1629         if (r)
1630                 return -EFAULT;
1631         return 0;
1632 }
1633
1634 int kvm_read_guest_page(struct kvm *kvm, gfn_t gfn, void *data, int offset,
1635                         int len)
1636 {
1637         struct kvm_memory_slot *slot = gfn_to_memslot(kvm, gfn);
1638
1639         return __kvm_read_guest_page(slot, gfn, data, offset, len);
1640 }
1641 EXPORT_SYMBOL_GPL(kvm_read_guest_page);
1642
1643 int kvm_vcpu_read_guest_page(struct kvm_vcpu *vcpu, gfn_t gfn, void *data,
1644                              int offset, int len)
1645 {
1646         struct kvm_memory_slot *slot = kvm_vcpu_gfn_to_memslot(vcpu, gfn);
1647
1648         return __kvm_read_guest_page(slot, gfn, data, offset, len);
1649 }
1650 EXPORT_SYMBOL_GPL(kvm_vcpu_read_guest_page);
1651
1652 int kvm_read_guest(struct kvm *kvm, gpa_t gpa, void *data, unsigned long len)
1653 {
1654         gfn_t gfn = gpa >> PAGE_SHIFT;
1655         int seg;
1656         int offset = offset_in_page(gpa);
1657         int ret;
1658
1659         while ((seg = next_segment(len, offset)) != 0) {
1660                 ret = kvm_read_guest_page(kvm, gfn, data, offset, seg);
1661                 if (ret < 0)
1662                         return ret;
1663                 offset = 0;
1664                 len -= seg;
1665                 data += seg;
1666                 ++gfn;
1667         }
1668         return 0;
1669 }
1670 EXPORT_SYMBOL_GPL(kvm_read_guest);
1671
1672 int kvm_vcpu_read_guest(struct kvm_vcpu *vcpu, gpa_t gpa, void *data, unsigned long len)
1673 {
1674         gfn_t gfn = gpa >> PAGE_SHIFT;
1675         int seg;
1676         int offset = offset_in_page(gpa);
1677         int ret;
1678
1679         while ((seg = next_segment(len, offset)) != 0) {
1680                 ret = kvm_vcpu_read_guest_page(vcpu, gfn, data, offset, seg);
1681                 if (ret < 0)
1682                         return ret;
1683                 offset = 0;
1684                 len -= seg;
1685                 data += seg;
1686                 ++gfn;
1687         }
1688         return 0;
1689 }
1690 EXPORT_SYMBOL_GPL(kvm_vcpu_read_guest);
1691
1692 static int __kvm_read_guest_atomic(struct kvm_memory_slot *slot, gfn_t gfn,
1693                                    void *data, int offset, unsigned long len)
1694 {
1695         int r;
1696         unsigned long addr;
1697
1698         addr = gfn_to_hva_memslot_prot(slot, gfn, NULL);
1699         if (kvm_is_error_hva(addr))
1700                 return -EFAULT;
1701         pagefault_disable();
1702         r = __copy_from_user_inatomic(data, (void __user *)addr + offset, len);
1703         pagefault_enable();
1704         if (r)
1705                 return -EFAULT;
1706         return 0;
1707 }
1708
1709 int kvm_read_guest_atomic(struct kvm *kvm, gpa_t gpa, void *data,
1710                           unsigned long len)
1711 {
1712         gfn_t gfn = gpa >> PAGE_SHIFT;
1713         struct kvm_memory_slot *slot = gfn_to_memslot(kvm, gfn);
1714         int offset = offset_in_page(gpa);
1715
1716         return __kvm_read_guest_atomic(slot, gfn, data, offset, len);
1717 }
1718 EXPORT_SYMBOL_GPL(kvm_read_guest_atomic);
1719
1720 int kvm_vcpu_read_guest_atomic(struct kvm_vcpu *vcpu, gpa_t gpa,
1721                                void *data, unsigned long len)
1722 {
1723         gfn_t gfn = gpa >> PAGE_SHIFT;
1724         struct kvm_memory_slot *slot = kvm_vcpu_gfn_to_memslot(vcpu, gfn);
1725         int offset = offset_in_page(gpa);
1726
1727         return __kvm_read_guest_atomic(slot, gfn, data, offset, len);
1728 }
1729 EXPORT_SYMBOL_GPL(kvm_vcpu_read_guest_atomic);
1730
1731 static int __kvm_write_guest_page(struct kvm_memory_slot *memslot, gfn_t gfn,
1732                                   const void *data, int offset, int len)
1733 {
1734         int r;
1735         unsigned long addr;
1736
1737         addr = gfn_to_hva_memslot(memslot, gfn);
1738         if (kvm_is_error_hva(addr))
1739                 return -EFAULT;
1740         r = __copy_to_user((void __user *)addr + offset, data, len);
1741         if (r)
1742                 return -EFAULT;
1743         mark_page_dirty_in_slot(memslot, gfn);
1744         return 0;
1745 }
1746
1747 int kvm_write_guest_page(struct kvm *kvm, gfn_t gfn,
1748                          const void *data, int offset, int len)
1749 {
1750         struct kvm_memory_slot *slot = gfn_to_memslot(kvm, gfn);
1751
1752         return __kvm_write_guest_page(slot, gfn, data, offset, len);
1753 }
1754 EXPORT_SYMBOL_GPL(kvm_write_guest_page);
1755
1756 int kvm_vcpu_write_guest_page(struct kvm_vcpu *vcpu, gfn_t gfn,
1757                               const void *data, int offset, int len)
1758 {
1759         struct kvm_memory_slot *slot = kvm_vcpu_gfn_to_memslot(vcpu, gfn);
1760
1761         return __kvm_write_guest_page(slot, gfn, data, offset, len);
1762 }
1763 EXPORT_SYMBOL_GPL(kvm_vcpu_write_guest_page);
1764
1765 int kvm_write_guest(struct kvm *kvm, gpa_t gpa, const void *data,
1766                     unsigned long len)
1767 {
1768         gfn_t gfn = gpa >> PAGE_SHIFT;
1769         int seg;
1770         int offset = offset_in_page(gpa);
1771         int ret;
1772
1773         while ((seg = next_segment(len, offset)) != 0) {
1774                 ret = kvm_write_guest_page(kvm, gfn, data, offset, seg);
1775                 if (ret < 0)
1776                         return ret;
1777                 offset = 0;
1778                 len -= seg;
1779                 data += seg;
1780                 ++gfn;
1781         }
1782         return 0;
1783 }
1784 EXPORT_SYMBOL_GPL(kvm_write_guest);
1785
1786 int kvm_vcpu_write_guest(struct kvm_vcpu *vcpu, gpa_t gpa, const void *data,
1787                          unsigned long len)
1788 {
1789         gfn_t gfn = gpa >> PAGE_SHIFT;
1790         int seg;
1791         int offset = offset_in_page(gpa);
1792         int ret;
1793
1794         while ((seg = next_segment(len, offset)) != 0) {
1795                 ret = kvm_vcpu_write_guest_page(vcpu, gfn, data, offset, seg);
1796                 if (ret < 0)
1797                         return ret;
1798                 offset = 0;
1799                 len -= seg;
1800                 data += seg;
1801                 ++gfn;
1802         }
1803         return 0;
1804 }
1805 EXPORT_SYMBOL_GPL(kvm_vcpu_write_guest);
1806
1807 int kvm_gfn_to_hva_cache_init(struct kvm *kvm, struct gfn_to_hva_cache *ghc,
1808                               gpa_t gpa, unsigned long len)
1809 {
1810         struct kvm_memslots *slots = kvm_memslots(kvm);
1811         int offset = offset_in_page(gpa);
1812         gfn_t start_gfn = gpa >> PAGE_SHIFT;
1813         gfn_t end_gfn = (gpa + len - 1) >> PAGE_SHIFT;
1814         gfn_t nr_pages_needed = end_gfn - start_gfn + 1;
1815         gfn_t nr_pages_avail;
1816
1817         ghc->gpa = gpa;
1818         ghc->generation = slots->generation;
1819         ghc->len = len;
1820         ghc->memslot = gfn_to_memslot(kvm, start_gfn);
1821         ghc->hva = gfn_to_hva_many(ghc->memslot, start_gfn, NULL);
1822         if (!kvm_is_error_hva(ghc->hva) && nr_pages_needed <= 1) {
1823                 ghc->hva += offset;
1824         } else {
1825                 /*
1826                  * If the requested region crosses two memslots, we still
1827                  * verify that the entire region is valid here.
1828                  */
1829                 while (start_gfn <= end_gfn) {
1830                         ghc->memslot = gfn_to_memslot(kvm, start_gfn);
1831                         ghc->hva = gfn_to_hva_many(ghc->memslot, start_gfn,
1832                                                    &nr_pages_avail);
1833                         if (kvm_is_error_hva(ghc->hva))
1834                                 return -EFAULT;
1835                         start_gfn += nr_pages_avail;
1836                 }
1837                 /* Use the slow path for cross page reads and writes. */
1838                 ghc->memslot = NULL;
1839         }
1840         return 0;
1841 }
1842 EXPORT_SYMBOL_GPL(kvm_gfn_to_hva_cache_init);
1843
1844 int kvm_write_guest_cached(struct kvm *kvm, struct gfn_to_hva_cache *ghc,
1845                            void *data, unsigned long len)
1846 {
1847         struct kvm_memslots *slots = kvm_memslots(kvm);
1848         int r;
1849
1850         BUG_ON(len > ghc->len);
1851
1852         if (slots->generation != ghc->generation)
1853                 kvm_gfn_to_hva_cache_init(kvm, ghc, ghc->gpa, ghc->len);
1854
1855         if (unlikely(!ghc->memslot))
1856                 return kvm_write_guest(kvm, ghc->gpa, data, len);
1857
1858         if (kvm_is_error_hva(ghc->hva))
1859                 return -EFAULT;
1860
1861         r = __copy_to_user((void __user *)ghc->hva, data, len);
1862         if (r)
1863                 return -EFAULT;
1864         mark_page_dirty_in_slot(ghc->memslot, ghc->gpa >> PAGE_SHIFT);
1865
1866         return 0;
1867 }
1868 EXPORT_SYMBOL_GPL(kvm_write_guest_cached);
1869
1870 int kvm_read_guest_cached(struct kvm *kvm, struct gfn_to_hva_cache *ghc,
1871                            void *data, unsigned long len)
1872 {
1873         struct kvm_memslots *slots = kvm_memslots(kvm);
1874         int r;
1875
1876         BUG_ON(len > ghc->len);
1877
1878         if (slots->generation != ghc->generation)
1879                 kvm_gfn_to_hva_cache_init(kvm, ghc, ghc->gpa, ghc->len);
1880
1881         if (unlikely(!ghc->memslot))
1882                 return kvm_read_guest(kvm, ghc->gpa, data, len);
1883
1884         if (kvm_is_error_hva(ghc->hva))
1885                 return -EFAULT;
1886
1887         r = __copy_from_user(data, (void __user *)ghc->hva, len);
1888         if (r)
1889                 return -EFAULT;
1890
1891         return 0;
1892 }
1893 EXPORT_SYMBOL_GPL(kvm_read_guest_cached);
1894
1895 int kvm_clear_guest_page(struct kvm *kvm, gfn_t gfn, int offset, int len)
1896 {
1897         const void *zero_page = (const void *) __va(page_to_phys(ZERO_PAGE(0)));
1898
1899         return kvm_write_guest_page(kvm, gfn, zero_page, offset, len);
1900 }
1901 EXPORT_SYMBOL_GPL(kvm_clear_guest_page);
1902
1903 int kvm_clear_guest(struct kvm *kvm, gpa_t gpa, unsigned long len)
1904 {
1905         gfn_t gfn = gpa >> PAGE_SHIFT;
1906         int seg;
1907         int offset = offset_in_page(gpa);
1908         int ret;
1909
1910         while ((seg = next_segment(len, offset)) != 0) {
1911                 ret = kvm_clear_guest_page(kvm, gfn, offset, seg);
1912                 if (ret < 0)
1913                         return ret;
1914                 offset = 0;
1915                 len -= seg;
1916                 ++gfn;
1917         }
1918         return 0;
1919 }
1920 EXPORT_SYMBOL_GPL(kvm_clear_guest);
1921
1922 static void mark_page_dirty_in_slot(struct kvm_memory_slot *memslot,
1923                                     gfn_t gfn)
1924 {
1925         if (memslot && memslot->dirty_bitmap) {
1926                 unsigned long rel_gfn = gfn - memslot->base_gfn;
1927
1928                 set_bit_le(rel_gfn, memslot->dirty_bitmap);
1929         }
1930 }
1931
1932 void mark_page_dirty(struct kvm *kvm, gfn_t gfn)
1933 {
1934         struct kvm_memory_slot *memslot;
1935
1936         memslot = gfn_to_memslot(kvm, gfn);
1937         mark_page_dirty_in_slot(memslot, gfn);
1938 }
1939 EXPORT_SYMBOL_GPL(mark_page_dirty);
1940
1941 void kvm_vcpu_mark_page_dirty(struct kvm_vcpu *vcpu, gfn_t gfn)
1942 {
1943         struct kvm_memory_slot *memslot;
1944
1945         memslot = kvm_vcpu_gfn_to_memslot(vcpu, gfn);
1946         mark_page_dirty_in_slot(memslot, gfn);
1947 }
1948 EXPORT_SYMBOL_GPL(kvm_vcpu_mark_page_dirty);
1949
1950 static void grow_halt_poll_ns(struct kvm_vcpu *vcpu)
1951 {
1952         int old, val;
1953
1954         old = val = vcpu->halt_poll_ns;
1955         /* 10us base */
1956         if (val == 0 && halt_poll_ns_grow)
1957                 val = 10000;
1958         else
1959                 val *= halt_poll_ns_grow;
1960
1961         vcpu->halt_poll_ns = val;
1962         trace_kvm_halt_poll_ns_grow(vcpu->vcpu_id, val, old);
1963 }
1964
1965 static void shrink_halt_poll_ns(struct kvm_vcpu *vcpu)
1966 {
1967         int old, val;
1968
1969         old = val = vcpu->halt_poll_ns;
1970         if (halt_poll_ns_shrink == 0)
1971                 val = 0;
1972         else
1973                 val /= halt_poll_ns_shrink;
1974
1975         vcpu->halt_poll_ns = val;
1976         trace_kvm_halt_poll_ns_shrink(vcpu->vcpu_id, val, old);
1977 }
1978
1979 static int kvm_vcpu_check_block(struct kvm_vcpu *vcpu)
1980 {
1981         if (kvm_arch_vcpu_runnable(vcpu)) {
1982                 kvm_make_request(KVM_REQ_UNHALT, vcpu);
1983                 return -EINTR;
1984         }
1985         if (kvm_cpu_has_pending_timer(vcpu))
1986                 return -EINTR;
1987         if (signal_pending(current))
1988                 return -EINTR;
1989
1990         return 0;
1991 }
1992
1993 /*
1994  * The vCPU has executed a HLT instruction with in-kernel mode enabled.
1995  */
1996 void kvm_vcpu_block(struct kvm_vcpu *vcpu)
1997 {
1998         ktime_t start, cur;
1999         DEFINE_WAIT(wait);
2000         bool waited = false;
2001         u64 block_ns;
2002
2003         start = cur = ktime_get();
2004         if (vcpu->halt_poll_ns) {
2005                 ktime_t stop = ktime_add_ns(ktime_get(), vcpu->halt_poll_ns);
2006
2007                 do {
2008                         /*
2009                          * This sets KVM_REQ_UNHALT if an interrupt
2010                          * arrives.
2011                          */
2012                         if (kvm_vcpu_check_block(vcpu) < 0) {
2013                                 ++vcpu->stat.halt_successful_poll;
2014                                 goto out;
2015                         }
2016                         cur = ktime_get();
2017                 } while (single_task_running() && ktime_before(cur, stop));
2018         }
2019
2020         for (;;) {
2021                 prepare_to_wait(&vcpu->wq, &wait, TASK_INTERRUPTIBLE);
2022
2023                 if (kvm_vcpu_check_block(vcpu) < 0)
2024                         break;
2025
2026                 waited = true;
2027                 schedule();
2028         }
2029
2030         finish_wait(&vcpu->wq, &wait);
2031         cur = ktime_get();
2032
2033 out:
2034         block_ns = ktime_to_ns(cur) - ktime_to_ns(start);
2035
2036         if (halt_poll_ns) {
2037                 if (block_ns <= vcpu->halt_poll_ns)
2038                         ;
2039                 /* we had a long block, shrink polling */
2040                 else if (vcpu->halt_poll_ns && block_ns > halt_poll_ns)
2041                         shrink_halt_poll_ns(vcpu);
2042                 /* we had a short halt and our poll time is too small */
2043                 else if (vcpu->halt_poll_ns < halt_poll_ns &&
2044                         block_ns < halt_poll_ns)
2045                         grow_halt_poll_ns(vcpu);
2046         } else
2047                 vcpu->halt_poll_ns = 0;
2048
2049         trace_kvm_vcpu_wakeup(block_ns, waited);
2050 }
2051 EXPORT_SYMBOL_GPL(kvm_vcpu_block);
2052
2053 #ifndef CONFIG_S390
2054 /*
2055  * Kick a sleeping VCPU, or a guest VCPU in guest mode, into host kernel mode.
2056  */
2057 void kvm_vcpu_kick(struct kvm_vcpu *vcpu)
2058 {
2059         int me;
2060         int cpu = vcpu->cpu;
2061         wait_queue_head_t *wqp;
2062
2063         wqp = kvm_arch_vcpu_wq(vcpu);
2064         if (waitqueue_active(wqp)) {
2065                 wake_up_interruptible(wqp);
2066                 ++vcpu->stat.halt_wakeup;
2067         }
2068
2069         me = get_cpu();
2070         if (cpu != me && (unsigned)cpu < nr_cpu_ids && cpu_online(cpu))
2071                 if (kvm_arch_vcpu_should_kick(vcpu))
2072                         smp_send_reschedule(cpu);
2073         put_cpu();
2074 }
2075 EXPORT_SYMBOL_GPL(kvm_vcpu_kick);
2076 #endif /* !CONFIG_S390 */
2077
2078 int kvm_vcpu_yield_to(struct kvm_vcpu *target)
2079 {
2080         struct pid *pid;
2081         struct task_struct *task = NULL;
2082         int ret = 0;
2083
2084         rcu_read_lock();
2085         pid = rcu_dereference(target->pid);
2086         if (pid)
2087                 task = get_pid_task(pid, PIDTYPE_PID);
2088         rcu_read_unlock();
2089         if (!task)
2090                 return ret;
2091         ret = yield_to(task, 1);
2092         put_task_struct(task);
2093
2094         return ret;
2095 }
2096 EXPORT_SYMBOL_GPL(kvm_vcpu_yield_to);
2097
2098 /*
2099  * Helper that checks whether a VCPU is eligible for directed yield.
2100  * Most eligible candidate to yield is decided by following heuristics:
2101  *
2102  *  (a) VCPU which has not done pl-exit or cpu relax intercepted recently
2103  *  (preempted lock holder), indicated by @in_spin_loop.
2104  *  Set at the beiginning and cleared at the end of interception/PLE handler.
2105  *
2106  *  (b) VCPU which has done pl-exit/ cpu relax intercepted but did not get
2107  *  chance last time (mostly it has become eligible now since we have probably
2108  *  yielded to lockholder in last iteration. This is done by toggling
2109  *  @dy_eligible each time a VCPU checked for eligibility.)
2110  *
2111  *  Yielding to a recently pl-exited/cpu relax intercepted VCPU before yielding
2112  *  to preempted lock-holder could result in wrong VCPU selection and CPU
2113  *  burning. Giving priority for a potential lock-holder increases lock
2114  *  progress.
2115  *
2116  *  Since algorithm is based on heuristics, accessing another VCPU data without
2117  *  locking does not harm. It may result in trying to yield to  same VCPU, fail
2118  *  and continue with next VCPU and so on.
2119  */
2120 static bool kvm_vcpu_eligible_for_directed_yield(struct kvm_vcpu *vcpu)
2121 {
2122 #ifdef CONFIG_HAVE_KVM_CPU_RELAX_INTERCEPT
2123         bool eligible;
2124
2125         eligible = !vcpu->spin_loop.in_spin_loop ||
2126                     vcpu->spin_loop.dy_eligible;
2127
2128         if (vcpu->spin_loop.in_spin_loop)
2129                 kvm_vcpu_set_dy_eligible(vcpu, !vcpu->spin_loop.dy_eligible);
2130
2131         return eligible;
2132 #else
2133         return true;
2134 #endif
2135 }
2136
2137 void kvm_vcpu_on_spin(struct kvm_vcpu *me)
2138 {
2139         struct kvm *kvm = me->kvm;
2140         struct kvm_vcpu *vcpu;
2141         int last_boosted_vcpu = me->kvm->last_boosted_vcpu;
2142         int yielded = 0;
2143         int try = 3;
2144         int pass;
2145         int i;
2146
2147         kvm_vcpu_set_in_spin_loop(me, true);
2148         /*
2149          * We boost the priority of a VCPU that is runnable but not
2150          * currently running, because it got preempted by something
2151          * else and called schedule in __vcpu_run.  Hopefully that
2152          * VCPU is holding the lock that we need and will release it.
2153          * We approximate round-robin by starting at the last boosted VCPU.
2154          */
2155         for (pass = 0; pass < 2 && !yielded && try; pass++) {
2156                 kvm_for_each_vcpu(i, vcpu, kvm) {
2157                         if (!pass && i <= last_boosted_vcpu) {
2158                                 i = last_boosted_vcpu;
2159                                 continue;
2160                         } else if (pass && i > last_boosted_vcpu)
2161                                 break;
2162                         if (!ACCESS_ONCE(vcpu->preempted))
2163                                 continue;
2164                         if (vcpu == me)
2165                                 continue;
2166                         if (waitqueue_active(&vcpu->wq) && !kvm_arch_vcpu_runnable(vcpu))
2167                                 continue;
2168                         if (!kvm_vcpu_eligible_for_directed_yield(vcpu))
2169                                 continue;
2170
2171                         yielded = kvm_vcpu_yield_to(vcpu);
2172                         if (yielded > 0) {
2173                                 kvm->last_boosted_vcpu = i;
2174                                 break;
2175                         } else if (yielded < 0) {
2176                                 try--;
2177                                 if (!try)
2178                                         break;
2179                         }
2180                 }
2181         }
2182         kvm_vcpu_set_in_spin_loop(me, false);
2183
2184         /* Ensure vcpu is not eligible during next spinloop */
2185         kvm_vcpu_set_dy_eligible(me, false);
2186 }
2187 EXPORT_SYMBOL_GPL(kvm_vcpu_on_spin);
2188
2189 static int kvm_vcpu_fault(struct vm_area_struct *vma, struct vm_fault *vmf)
2190 {
2191         struct kvm_vcpu *vcpu = vma->vm_file->private_data;
2192         struct page *page;
2193
2194         if (vmf->pgoff == 0)
2195                 page = virt_to_page(vcpu->run);
2196 #ifdef CONFIG_X86
2197         else if (vmf->pgoff == KVM_PIO_PAGE_OFFSET)
2198                 page = virt_to_page(vcpu->arch.pio_data);
2199 #endif
2200 #ifdef KVM_COALESCED_MMIO_PAGE_OFFSET
2201         else if (vmf->pgoff == KVM_COALESCED_MMIO_PAGE_OFFSET)
2202                 page = virt_to_page(vcpu->kvm->coalesced_mmio_ring);
2203 #endif
2204         else
2205                 return kvm_arch_vcpu_fault(vcpu, vmf);
2206         get_page(page);
2207         vmf->page = page;
2208         return 0;
2209 }
2210
2211 static const struct vm_operations_struct kvm_vcpu_vm_ops = {
2212         .fault = kvm_vcpu_fault,
2213 };
2214
2215 static int kvm_vcpu_mmap(struct file *file, struct vm_area_struct *vma)
2216 {
2217         vma->vm_ops = &kvm_vcpu_vm_ops;
2218         return 0;
2219 }
2220
2221 static int kvm_vcpu_release(struct inode *inode, struct file *filp)
2222 {
2223         struct kvm_vcpu *vcpu = filp->private_data;
2224
2225         kvm_put_kvm(vcpu->kvm);
2226         return 0;
2227 }
2228
2229 static struct file_operations kvm_vcpu_fops = {
2230         .release        = kvm_vcpu_release,
2231         .unlocked_ioctl = kvm_vcpu_ioctl,
2232 #ifdef CONFIG_KVM_COMPAT
2233         .compat_ioctl   = kvm_vcpu_compat_ioctl,
2234 #endif
2235         .mmap           = kvm_vcpu_mmap,
2236         .llseek         = noop_llseek,
2237 };
2238
2239 /*
2240  * Allocates an inode for the vcpu.
2241  */
2242 static int create_vcpu_fd(struct kvm_vcpu *vcpu)
2243 {
2244         return anon_inode_getfd("kvm-vcpu", &kvm_vcpu_fops, vcpu, O_RDWR | O_CLOEXEC);
2245 }
2246
2247 /*
2248  * Creates some virtual cpus.  Good luck creating more than one.
2249  */
2250 static int kvm_vm_ioctl_create_vcpu(struct kvm *kvm, u32 id)
2251 {
2252         int r;
2253         struct kvm_vcpu *vcpu, *v;
2254
2255         if (id >= KVM_MAX_VCPUS)
2256                 return -EINVAL;
2257
2258         vcpu = kvm_arch_vcpu_create(kvm, id);
2259         if (IS_ERR(vcpu))
2260                 return PTR_ERR(vcpu);
2261
2262         preempt_notifier_init(&vcpu->preempt_notifier, &kvm_preempt_ops);
2263
2264         r = kvm_arch_vcpu_setup(vcpu);
2265         if (r)
2266                 goto vcpu_destroy;
2267
2268         mutex_lock(&kvm->lock);
2269         if (!kvm_vcpu_compatible(vcpu)) {
2270                 r = -EINVAL;
2271                 goto unlock_vcpu_destroy;
2272         }
2273         if (atomic_read(&kvm->online_vcpus) == KVM_MAX_VCPUS) {
2274                 r = -EINVAL;
2275                 goto unlock_vcpu_destroy;
2276         }
2277
2278         kvm_for_each_vcpu(r, v, kvm)
2279                 if (v->vcpu_id == id) {
2280                         r = -EEXIST;
2281                         goto unlock_vcpu_destroy;
2282                 }
2283
2284         BUG_ON(kvm->vcpus[atomic_read(&kvm->online_vcpus)]);
2285
2286         /* Now it's all set up, let userspace reach it */
2287         kvm_get_kvm(kvm);
2288         r = create_vcpu_fd(vcpu);
2289         if (r < 0) {
2290                 kvm_put_kvm(kvm);
2291                 goto unlock_vcpu_destroy;
2292         }
2293
2294         kvm->vcpus[atomic_read(&kvm->online_vcpus)] = vcpu;
2295
2296         /*
2297          * Pairs with smp_rmb() in kvm_get_vcpu.  Write kvm->vcpus
2298          * before kvm->online_vcpu's incremented value.
2299          */
2300         smp_wmb();
2301         atomic_inc(&kvm->online_vcpus);
2302
2303         mutex_unlock(&kvm->lock);
2304         kvm_arch_vcpu_postcreate(vcpu);
2305         return r;
2306
2307 unlock_vcpu_destroy:
2308         mutex_unlock(&kvm->lock);
2309 vcpu_destroy:
2310         kvm_arch_vcpu_destroy(vcpu);
2311         return r;
2312 }
2313
2314 static int kvm_vcpu_ioctl_set_sigmask(struct kvm_vcpu *vcpu, sigset_t *sigset)
2315 {
2316         if (sigset) {
2317                 sigdelsetmask(sigset, sigmask(SIGKILL)|sigmask(SIGSTOP));
2318                 vcpu->sigset_active = 1;
2319                 vcpu->sigset = *sigset;
2320         } else
2321                 vcpu->sigset_active = 0;
2322         return 0;
2323 }
2324
2325 static long kvm_vcpu_ioctl(struct file *filp,
2326                            unsigned int ioctl, unsigned long arg)
2327 {
2328         struct kvm_vcpu *vcpu = filp->private_data;
2329         void __user *argp = (void __user *)arg;
2330         int r;
2331         struct kvm_fpu *fpu = NULL;
2332         struct kvm_sregs *kvm_sregs = NULL;
2333
2334         if (vcpu->kvm->mm != current->mm)
2335                 return -EIO;
2336
2337         if (unlikely(_IOC_TYPE(ioctl) != KVMIO))
2338                 return -EINVAL;
2339
2340 #if defined(CONFIG_S390) || defined(CONFIG_PPC) || defined(CONFIG_MIPS)
2341         /*
2342          * Special cases: vcpu ioctls that are asynchronous to vcpu execution,
2343          * so vcpu_load() would break it.
2344          */
2345         if (ioctl == KVM_S390_INTERRUPT || ioctl == KVM_S390_IRQ || ioctl == KVM_INTERRUPT)
2346                 return kvm_arch_vcpu_ioctl(filp, ioctl, arg);
2347 #endif
2348
2349
2350         r = vcpu_load(vcpu);
2351         if (r)
2352                 return r;
2353         switch (ioctl) {
2354         case KVM_RUN:
2355                 r = -EINVAL;
2356                 if (arg)
2357                         goto out;
2358                 if (unlikely(vcpu->pid != current->pids[PIDTYPE_PID].pid)) {
2359                         /* The thread running this VCPU changed. */
2360                         struct pid *oldpid = vcpu->pid;
2361                         struct pid *newpid = get_task_pid(current, PIDTYPE_PID);
2362
2363                         rcu_assign_pointer(vcpu->pid, newpid);
2364                         if (oldpid)
2365                                 synchronize_rcu();
2366                         put_pid(oldpid);
2367                 }
2368                 r = kvm_arch_vcpu_ioctl_run(vcpu, vcpu->run);
2369                 trace_kvm_userspace_exit(vcpu->run->exit_reason, r);
2370                 break;
2371         case KVM_GET_REGS: {
2372                 struct kvm_regs *kvm_regs;
2373
2374                 r = -ENOMEM;
2375                 kvm_regs = kzalloc(sizeof(struct kvm_regs), GFP_KERNEL);
2376                 if (!kvm_regs)
2377                         goto out;
2378                 r = kvm_arch_vcpu_ioctl_get_regs(vcpu, kvm_regs);
2379                 if (r)
2380                         goto out_free1;
2381                 r = -EFAULT;
2382                 if (copy_to_user(argp, kvm_regs, sizeof(struct kvm_regs)))
2383                         goto out_free1;
2384                 r = 0;
2385 out_free1:
2386                 kfree(kvm_regs);
2387                 break;
2388         }
2389         case KVM_SET_REGS: {
2390                 struct kvm_regs *kvm_regs;
2391
2392                 r = -ENOMEM;
2393                 kvm_regs = memdup_user(argp, sizeof(*kvm_regs));
2394                 if (IS_ERR(kvm_regs)) {
2395                         r = PTR_ERR(kvm_regs);
2396                         goto out;
2397                 }
2398                 r = kvm_arch_vcpu_ioctl_set_regs(vcpu, kvm_regs);
2399                 kfree(kvm_regs);
2400                 break;
2401         }
2402         case KVM_GET_SREGS: {
2403                 kvm_sregs = kzalloc(sizeof(struct kvm_sregs), GFP_KERNEL);
2404                 r = -ENOMEM;
2405                 if (!kvm_sregs)
2406                         goto out;
2407                 r = kvm_arch_vcpu_ioctl_get_sregs(vcpu, kvm_sregs);
2408                 if (r)
2409                         goto out;
2410                 r = -EFAULT;
2411                 if (copy_to_user(argp, kvm_sregs, sizeof(struct kvm_sregs)))
2412                         goto out;
2413                 r = 0;
2414                 break;
2415         }
2416         case KVM_SET_SREGS: {
2417                 kvm_sregs = memdup_user(argp, sizeof(*kvm_sregs));
2418                 if (IS_ERR(kvm_sregs)) {
2419                         r = PTR_ERR(kvm_sregs);
2420                         kvm_sregs = NULL;
2421                         goto out;
2422                 }
2423                 r = kvm_arch_vcpu_ioctl_set_sregs(vcpu, kvm_sregs);
2424                 break;
2425         }
2426         case KVM_GET_MP_STATE: {
2427                 struct kvm_mp_state mp_state;
2428
2429                 r = kvm_arch_vcpu_ioctl_get_mpstate(vcpu, &mp_state);
2430                 if (r)
2431                         goto out;
2432                 r = -EFAULT;
2433                 if (copy_to_user(argp, &mp_state, sizeof(mp_state)))
2434                         goto out;
2435                 r = 0;
2436                 break;
2437         }
2438         case KVM_SET_MP_STATE: {
2439                 struct kvm_mp_state mp_state;
2440
2441                 r = -EFAULT;
2442                 if (copy_from_user(&mp_state, argp, sizeof(mp_state)))
2443                         goto out;
2444                 r = kvm_arch_vcpu_ioctl_set_mpstate(vcpu, &mp_state);
2445                 break;
2446         }
2447         case KVM_TRANSLATE: {
2448                 struct kvm_translation tr;
2449
2450                 r = -EFAULT;
2451                 if (copy_from_user(&tr, argp, sizeof(tr)))
2452                         goto out;
2453                 r = kvm_arch_vcpu_ioctl_translate(vcpu, &tr);
2454                 if (r)
2455                         goto out;
2456                 r = -EFAULT;
2457                 if (copy_to_user(argp, &tr, sizeof(tr)))
2458                         goto out;
2459                 r = 0;
2460                 break;
2461         }
2462         case KVM_SET_GUEST_DEBUG: {
2463                 struct kvm_guest_debug dbg;
2464
2465                 r = -EFAULT;
2466                 if (copy_from_user(&dbg, argp, sizeof(dbg)))
2467                         goto out;
2468                 r = kvm_arch_vcpu_ioctl_set_guest_debug(vcpu, &dbg);
2469                 break;
2470         }
2471         case KVM_SET_SIGNAL_MASK: {
2472                 struct kvm_signal_mask __user *sigmask_arg = argp;
2473                 struct kvm_signal_mask kvm_sigmask;
2474                 sigset_t sigset, *p;
2475
2476                 p = NULL;
2477                 if (argp) {
2478                         r = -EFAULT;
2479                         if (copy_from_user(&kvm_sigmask, argp,
2480                                            sizeof(kvm_sigmask)))
2481                                 goto out;
2482                         r = -EINVAL;
2483                         if (kvm_sigmask.len != sizeof(sigset))
2484                                 goto out;
2485                         r = -EFAULT;
2486                         if (copy_from_user(&sigset, sigmask_arg->sigset,
2487                                            sizeof(sigset)))
2488                                 goto out;
2489                         p = &sigset;
2490                 }
2491                 r = kvm_vcpu_ioctl_set_sigmask(vcpu, p);
2492                 break;
2493         }
2494         case KVM_GET_FPU: {
2495                 fpu = kzalloc(sizeof(struct kvm_fpu), GFP_KERNEL);
2496                 r = -ENOMEM;
2497                 if (!fpu)
2498                         goto out;
2499                 r = kvm_arch_vcpu_ioctl_get_fpu(vcpu, fpu);
2500                 if (r)
2501                         goto out;
2502                 r = -EFAULT;
2503                 if (copy_to_user(argp, fpu, sizeof(struct kvm_fpu)))
2504                         goto out;
2505                 r = 0;
2506                 break;
2507         }
2508         case KVM_SET_FPU: {
2509                 fpu = memdup_user(argp, sizeof(*fpu));
2510                 if (IS_ERR(fpu)) {
2511                         r = PTR_ERR(fpu);
2512                         fpu = NULL;
2513                         goto out;
2514                 }
2515                 r = kvm_arch_vcpu_ioctl_set_fpu(vcpu, fpu);
2516                 break;
2517         }
2518         default:
2519                 r = kvm_arch_vcpu_ioctl(filp, ioctl, arg);
2520         }
2521 out:
2522         vcpu_put(vcpu);
2523         kfree(fpu);
2524         kfree(kvm_sregs);
2525         return r;
2526 }
2527
2528 #ifdef CONFIG_KVM_COMPAT
2529 static long kvm_vcpu_compat_ioctl(struct file *filp,
2530                                   unsigned int ioctl, unsigned long arg)
2531 {
2532         struct kvm_vcpu *vcpu = filp->private_data;
2533         void __user *argp = compat_ptr(arg);
2534         int r;
2535
2536         if (vcpu->kvm->mm != current->mm)
2537                 return -EIO;
2538
2539         switch (ioctl) {
2540         case KVM_SET_SIGNAL_MASK: {
2541                 struct kvm_signal_mask __user *sigmask_arg = argp;
2542                 struct kvm_signal_mask kvm_sigmask;
2543                 compat_sigset_t csigset;
2544                 sigset_t sigset;
2545
2546                 if (argp) {
2547                         r = -EFAULT;
2548                         if (copy_from_user(&kvm_sigmask, argp,
2549                                            sizeof(kvm_sigmask)))
2550                                 goto out;
2551                         r = -EINVAL;
2552                         if (kvm_sigmask.len != sizeof(csigset))
2553                                 goto out;
2554                         r = -EFAULT;
2555                         if (copy_from_user(&csigset, sigmask_arg->sigset,
2556                                            sizeof(csigset)))
2557                                 goto out;
2558                         sigset_from_compat(&sigset, &csigset);
2559                         r = kvm_vcpu_ioctl_set_sigmask(vcpu, &sigset);
2560                 } else
2561                         r = kvm_vcpu_ioctl_set_sigmask(vcpu, NULL);
2562                 break;
2563         }
2564         default:
2565                 r = kvm_vcpu_ioctl(filp, ioctl, arg);
2566         }
2567
2568 out:
2569         return r;
2570 }
2571 #endif
2572
2573 static int kvm_device_ioctl_attr(struct kvm_device *dev,
2574                                  int (*accessor)(struct kvm_device *dev,
2575                                                  struct kvm_device_attr *attr),
2576                                  unsigned long arg)
2577 {
2578         struct kvm_device_attr attr;
2579
2580         if (!accessor)
2581                 return -EPERM;
2582
2583         if (copy_from_user(&attr, (void __user *)arg, sizeof(attr)))
2584                 return -EFAULT;
2585
2586         return accessor(dev, &attr);
2587 }
2588
2589 static long kvm_device_ioctl(struct file *filp, unsigned int ioctl,
2590                              unsigned long arg)
2591 {
2592         struct kvm_device *dev = filp->private_data;
2593
2594         switch (ioctl) {
2595         case KVM_SET_DEVICE_ATTR:
2596                 return kvm_device_ioctl_attr(dev, dev->ops->set_attr, arg);
2597         case KVM_GET_DEVICE_ATTR:
2598                 return kvm_device_ioctl_attr(dev, dev->ops->get_attr, arg);
2599         case KVM_HAS_DEVICE_ATTR:
2600                 return kvm_device_ioctl_attr(dev, dev->ops->has_attr, arg);
2601         default:
2602                 if (dev->ops->ioctl)
2603                         return dev->ops->ioctl(dev, ioctl, arg);
2604
2605                 return -ENOTTY;
2606         }
2607 }
2608
2609 static int kvm_device_release(struct inode *inode, struct file *filp)
2610 {
2611         struct kvm_device *dev = filp->private_data;
2612         struct kvm *kvm = dev->kvm;
2613
2614         kvm_put_kvm(kvm);
2615         return 0;
2616 }
2617
2618 static const struct file_operations kvm_device_fops = {
2619         .unlocked_ioctl = kvm_device_ioctl,
2620 #ifdef CONFIG_KVM_COMPAT
2621         .compat_ioctl = kvm_device_ioctl,
2622 #endif
2623         .release = kvm_device_release,
2624 };
2625
2626 struct kvm_device *kvm_device_from_filp(struct file *filp)
2627 {
2628         if (filp->f_op != &kvm_device_fops)
2629                 return NULL;
2630
2631         return filp->private_data;
2632 }
2633
2634 static struct kvm_device_ops *kvm_device_ops_table[KVM_DEV_TYPE_MAX] = {
2635 #ifdef CONFIG_KVM_MPIC
2636         [KVM_DEV_TYPE_FSL_MPIC_20]      = &kvm_mpic_ops,
2637         [KVM_DEV_TYPE_FSL_MPIC_42]      = &kvm_mpic_ops,
2638 #endif
2639
2640 #ifdef CONFIG_KVM_XICS
2641         [KVM_DEV_TYPE_XICS]             = &kvm_xics_ops,
2642 #endif
2643 };
2644
2645 int kvm_register_device_ops(struct kvm_device_ops *ops, u32 type)
2646 {
2647         if (type >= ARRAY_SIZE(kvm_device_ops_table))
2648                 return -ENOSPC;
2649
2650         if (kvm_device_ops_table[type] != NULL)
2651                 return -EEXIST;
2652
2653         kvm_device_ops_table[type] = ops;
2654         return 0;
2655 }
2656
2657 void kvm_unregister_device_ops(u32 type)
2658 {
2659         if (kvm_device_ops_table[type] != NULL)
2660                 kvm_device_ops_table[type] = NULL;
2661 }
2662
2663 static int kvm_ioctl_create_device(struct kvm *kvm,
2664                                    struct kvm_create_device *cd)
2665 {
2666         struct kvm_device_ops *ops = NULL;
2667         struct kvm_device *dev;
2668         bool test = cd->flags & KVM_CREATE_DEVICE_TEST;
2669         int ret;
2670
2671         if (cd->type >= ARRAY_SIZE(kvm_device_ops_table))
2672                 return -ENODEV;
2673
2674         ops = kvm_device_ops_table[cd->type];
2675         if (ops == NULL)
2676                 return -ENODEV;
2677
2678         if (test)
2679                 return 0;
2680
2681         dev = kzalloc(sizeof(*dev), GFP_KERNEL);
2682         if (!dev)
2683                 return -ENOMEM;
2684
2685         dev->ops = ops;
2686         dev->kvm = kvm;
2687
2688         ret = ops->create(dev, cd->type);
2689         if (ret < 0) {
2690                 kfree(dev);
2691                 return ret;
2692         }
2693
2694         ret = anon_inode_getfd(ops->name, &kvm_device_fops, dev, O_RDWR | O_CLOEXEC);
2695         if (ret < 0) {
2696                 ops->destroy(dev);
2697                 return ret;
2698         }
2699
2700         list_add(&dev->vm_node, &kvm->devices);
2701         kvm_get_kvm(kvm);
2702         cd->fd = ret;
2703         return 0;
2704 }
2705
2706 static long kvm_vm_ioctl_check_extension_generic(struct kvm *kvm, long arg)
2707 {
2708         switch (arg) {
2709         case KVM_CAP_USER_MEMORY:
2710         case KVM_CAP_DESTROY_MEMORY_REGION_WORKS:
2711         case KVM_CAP_JOIN_MEMORY_REGIONS_WORKS:
2712         case KVM_CAP_INTERNAL_ERROR_DATA:
2713 #ifdef CONFIG_HAVE_KVM_MSI
2714         case KVM_CAP_SIGNAL_MSI:
2715 #endif
2716 #ifdef CONFIG_HAVE_KVM_IRQFD
2717         case KVM_CAP_IRQFD:
2718         case KVM_CAP_IRQFD_RESAMPLE:
2719 #endif
2720         case KVM_CAP_CHECK_EXTENSION_VM:
2721                 return 1;
2722 #ifdef CONFIG_HAVE_KVM_IRQ_ROUTING
2723         case KVM_CAP_IRQ_ROUTING:
2724                 return KVM_MAX_IRQ_ROUTES;
2725 #endif
2726 #if KVM_ADDRESS_SPACE_NUM > 1
2727         case KVM_CAP_MULTI_ADDRESS_SPACE:
2728                 return KVM_ADDRESS_SPACE_NUM;
2729 #endif
2730         default:
2731                 break;
2732         }
2733         return kvm_vm_ioctl_check_extension(kvm, arg);
2734 }
2735
2736 static long kvm_vm_ioctl(struct file *filp,
2737                            unsigned int ioctl, unsigned long arg)
2738 {
2739         struct kvm *kvm = filp->private_data;
2740         void __user *argp = (void __user *)arg;
2741         int r;
2742
2743         if (kvm->mm != current->mm)
2744                 return -EIO;
2745         switch (ioctl) {
2746         case KVM_CREATE_VCPU:
2747                 r = kvm_vm_ioctl_create_vcpu(kvm, arg);
2748                 break;
2749         case KVM_SET_USER_MEMORY_REGION: {
2750                 struct kvm_userspace_memory_region kvm_userspace_mem;
2751
2752                 r = -EFAULT;
2753                 if (copy_from_user(&kvm_userspace_mem, argp,
2754                                                 sizeof(kvm_userspace_mem)))
2755                         goto out;
2756
2757                 r = kvm_vm_ioctl_set_memory_region(kvm, &kvm_userspace_mem);
2758                 break;
2759         }
2760         case KVM_GET_DIRTY_LOG: {
2761                 struct kvm_dirty_log log;
2762
2763                 r = -EFAULT;
2764                 if (copy_from_user(&log, argp, sizeof(log)))
2765                         goto out;
2766                 r = kvm_vm_ioctl_get_dirty_log(kvm, &log);
2767                 break;
2768         }
2769 #ifdef KVM_COALESCED_MMIO_PAGE_OFFSET
2770         case KVM_REGISTER_COALESCED_MMIO: {
2771                 struct kvm_coalesced_mmio_zone zone;
2772
2773                 r = -EFAULT;
2774                 if (copy_from_user(&zone, argp, sizeof(zone)))
2775                         goto out;
2776                 r = kvm_vm_ioctl_register_coalesced_mmio(kvm, &zone);
2777                 break;
2778         }
2779         case KVM_UNREGISTER_COALESCED_MMIO: {
2780                 struct kvm_coalesced_mmio_zone zone;
2781
2782                 r = -EFAULT;
2783                 if (copy_from_user(&zone, argp, sizeof(zone)))
2784                         goto out;
2785                 r = kvm_vm_ioctl_unregister_coalesced_mmio(kvm, &zone);
2786                 break;
2787         }
2788 #endif
2789         case KVM_IRQFD: {
2790                 struct kvm_irqfd data;
2791
2792                 r = -EFAULT;
2793                 if (copy_from_user(&data, argp, sizeof(data)))
2794                         goto out;
2795                 r = kvm_irqfd(kvm, &data);
2796                 break;
2797         }
2798         case KVM_IOEVENTFD: {
2799                 struct kvm_ioeventfd data;
2800
2801                 r = -EFAULT;
2802                 if (copy_from_user(&data, argp, sizeof(data)))
2803                         goto out;
2804                 r = kvm_ioeventfd(kvm, &data);
2805                 break;
2806         }
2807 #ifdef CONFIG_HAVE_KVM_MSI
2808         case KVM_SIGNAL_MSI: {
2809                 struct kvm_msi msi;
2810
2811                 r = -EFAULT;
2812                 if (copy_from_user(&msi, argp, sizeof(msi)))
2813                         goto out;
2814                 r = kvm_send_userspace_msi(kvm, &msi);
2815                 break;
2816         }
2817 #endif
2818 #ifdef __KVM_HAVE_IRQ_LINE
2819         case KVM_IRQ_LINE_STATUS:
2820         case KVM_IRQ_LINE: {
2821                 struct kvm_irq_level irq_event;
2822
2823                 r = -EFAULT;
2824                 if (copy_from_user(&irq_event, argp, sizeof(irq_event)))
2825                         goto out;
2826
2827                 r = kvm_vm_ioctl_irq_line(kvm, &irq_event,
2828                                         ioctl == KVM_IRQ_LINE_STATUS);
2829                 if (r)
2830                         goto out;
2831
2832                 r = -EFAULT;
2833                 if (ioctl == KVM_IRQ_LINE_STATUS) {
2834                         if (copy_to_user(argp, &irq_event, sizeof(irq_event)))
2835                                 goto out;
2836                 }
2837
2838                 r = 0;
2839                 break;
2840         }
2841 #endif
2842 #ifdef CONFIG_HAVE_KVM_IRQ_ROUTING
2843         case KVM_SET_GSI_ROUTING: {
2844                 struct kvm_irq_routing routing;
2845                 struct kvm_irq_routing __user *urouting;
2846                 struct kvm_irq_routing_entry *entries;
2847
2848                 r = -EFAULT;
2849                 if (copy_from_user(&routing, argp, sizeof(routing)))
2850                         goto out;
2851                 r = -EINVAL;
2852                 if (routing.nr >= KVM_MAX_IRQ_ROUTES)
2853                         goto out;
2854                 if (routing.flags)
2855                         goto out;
2856                 r = -ENOMEM;
2857                 entries = vmalloc(routing.nr * sizeof(*entries));
2858                 if (!entries)
2859                         goto out;
2860                 r = -EFAULT;
2861                 urouting = argp;
2862                 if (copy_from_user(entries, urouting->entries,
2863                                    routing.nr * sizeof(*entries)))
2864                         goto out_free_irq_routing;
2865                 r = kvm_set_irq_routing(kvm, entries, routing.nr,
2866                                         routing.flags);
2867 out_free_irq_routing:
2868                 vfree(entries);
2869                 break;
2870         }
2871 #endif /* CONFIG_HAVE_KVM_IRQ_ROUTING */
2872         case KVM_CREATE_DEVICE: {
2873                 struct kvm_create_device cd;
2874
2875                 r = -EFAULT;
2876                 if (copy_from_user(&cd, argp, sizeof(cd)))
2877                         goto out;
2878
2879                 r = kvm_ioctl_create_device(kvm, &cd);
2880                 if (r)
2881                         goto out;
2882
2883                 r = -EFAULT;
2884                 if (copy_to_user(argp, &cd, sizeof(cd)))
2885                         goto out;
2886
2887                 r = 0;
2888                 break;
2889         }
2890         case KVM_CHECK_EXTENSION:
2891                 r = kvm_vm_ioctl_check_extension_generic(kvm, arg);
2892                 break;
2893         default:
2894                 r = kvm_arch_vm_ioctl(filp, ioctl, arg);
2895         }
2896 out:
2897         return r;
2898 }
2899
2900 #ifdef CONFIG_KVM_COMPAT
2901 struct compat_kvm_dirty_log {
2902         __u32 slot;
2903         __u32 padding1;
2904         union {
2905                 compat_uptr_t dirty_bitmap; /* one bit per page */
2906                 __u64 padding2;
2907         };
2908 };
2909
2910 static long kvm_vm_compat_ioctl(struct file *filp,
2911                            unsigned int ioctl, unsigned long arg)
2912 {
2913         struct kvm *kvm = filp->private_data;
2914         int r;
2915
2916         if (kvm->mm != current->mm)
2917                 return -EIO;
2918         switch (ioctl) {
2919         case KVM_GET_DIRTY_LOG: {
2920                 struct compat_kvm_dirty_log compat_log;
2921                 struct kvm_dirty_log log;
2922
2923                 r = -EFAULT;
2924                 if (copy_from_user(&compat_log, (void __user *)arg,
2925                                    sizeof(compat_log)))
2926                         goto out;
2927                 log.slot         = compat_log.slot;
2928                 log.padding1     = compat_log.padding1;
2929                 log.padding2     = compat_log.padding2;
2930                 log.dirty_bitmap = compat_ptr(compat_log.dirty_bitmap);
2931
2932                 r = kvm_vm_ioctl_get_dirty_log(kvm, &log);
2933                 break;
2934         }
2935         default:
2936                 r = kvm_vm_ioctl(filp, ioctl, arg);
2937         }
2938
2939 out:
2940         return r;
2941 }
2942 #endif
2943
2944 static struct file_operations kvm_vm_fops = {
2945         .release        = kvm_vm_release,
2946         .unlocked_ioctl = kvm_vm_ioctl,
2947 #ifdef CONFIG_KVM_COMPAT
2948         .compat_ioctl   = kvm_vm_compat_ioctl,
2949 #endif
2950         .llseek         = noop_llseek,
2951 };
2952
2953 static int kvm_dev_ioctl_create_vm(unsigned long type)
2954 {
2955         int r;
2956         struct kvm *kvm;
2957
2958         kvm = kvm_create_vm(type);
2959         if (IS_ERR(kvm))
2960                 return PTR_ERR(kvm);
2961 #ifdef KVM_COALESCED_MMIO_PAGE_OFFSET
2962         r = kvm_coalesced_mmio_init(kvm);
2963         if (r < 0) {
2964                 kvm_put_kvm(kvm);
2965                 return r;
2966         }
2967 #endif
2968         r = anon_inode_getfd("kvm-vm", &kvm_vm_fops, kvm, O_RDWR | O_CLOEXEC);
2969         if (r < 0)
2970                 kvm_put_kvm(kvm);
2971
2972         return r;
2973 }
2974
2975 static long kvm_dev_ioctl(struct file *filp,
2976                           unsigned int ioctl, unsigned long arg)
2977 {
2978         long r = -EINVAL;
2979
2980         switch (ioctl) {
2981         case KVM_GET_API_VERSION:
2982                 if (arg)
2983                         goto out;
2984                 r = KVM_API_VERSION;
2985                 break;
2986         case KVM_CREATE_VM:
2987                 r = kvm_dev_ioctl_create_vm(arg);
2988                 break;
2989         case KVM_CHECK_EXTENSION:
2990                 r = kvm_vm_ioctl_check_extension_generic(NULL, arg);
2991                 break;
2992         case KVM_GET_VCPU_MMAP_SIZE:
2993                 if (arg)
2994                         goto out;
2995                 r = PAGE_SIZE;     /* struct kvm_run */
2996 #ifdef CONFIG_X86
2997                 r += PAGE_SIZE;    /* pio data page */
2998 #endif
2999 #ifdef KVM_COALESCED_MMIO_PAGE_OFFSET
3000                 r += PAGE_SIZE;    /* coalesced mmio ring page */
3001 #endif
3002                 break;
3003         case KVM_TRACE_ENABLE:
3004         case KVM_TRACE_PAUSE:
3005         case KVM_TRACE_DISABLE:
3006                 r = -EOPNOTSUPP;
3007                 break;
3008         default:
3009                 return kvm_arch_dev_ioctl(filp, ioctl, arg);
3010         }
3011 out:
3012         return r;
3013 }
3014
3015 static struct file_operations kvm_chardev_ops = {
3016         .unlocked_ioctl = kvm_dev_ioctl,
3017         .compat_ioctl   = kvm_dev_ioctl,
3018         .llseek         = noop_llseek,
3019 };
3020
3021 static struct miscdevice kvm_dev = {
3022         KVM_MINOR,
3023         "kvm",
3024         &kvm_chardev_ops,
3025 };
3026
3027 static void hardware_enable_nolock(void *junk)
3028 {
3029         int cpu = raw_smp_processor_id();
3030         int r;
3031
3032         if (cpumask_test_cpu(cpu, cpus_hardware_enabled))
3033                 return;
3034
3035         cpumask_set_cpu(cpu, cpus_hardware_enabled);
3036
3037         r = kvm_arch_hardware_enable();
3038
3039         if (r) {
3040                 cpumask_clear_cpu(cpu, cpus_hardware_enabled);
3041                 atomic_inc(&hardware_enable_failed);
3042                 pr_info("kvm: enabling virtualization on CPU%d failed\n", cpu);
3043         }
3044 }
3045
3046 static void hardware_enable(void)
3047 {
3048         raw_spin_lock(&kvm_count_lock);
3049         if (kvm_usage_count)
3050                 hardware_enable_nolock(NULL);
3051         raw_spin_unlock(&kvm_count_lock);
3052 }
3053
3054 static void hardware_disable_nolock(void *junk)
3055 {
3056         int cpu = raw_smp_processor_id();
3057
3058         if (!cpumask_test_cpu(cpu, cpus_hardware_enabled))
3059                 return;
3060         cpumask_clear_cpu(cpu, cpus_hardware_enabled);
3061         kvm_arch_hardware_disable();
3062 }
3063
3064 static void hardware_disable(void)
3065 {
3066         raw_spin_lock(&kvm_count_lock);
3067         if (kvm_usage_count)
3068                 hardware_disable_nolock(NULL);
3069         raw_spin_unlock(&kvm_count_lock);
3070 }
3071
3072 static void hardware_disable_all_nolock(void)
3073 {
3074         BUG_ON(!kvm_usage_count);
3075
3076         kvm_usage_count--;
3077         if (!kvm_usage_count)
3078                 on_each_cpu(hardware_disable_nolock, NULL, 1);
3079 }
3080
3081 static void hardware_disable_all(void)
3082 {
3083         raw_spin_lock(&kvm_count_lock);
3084         hardware_disable_all_nolock();
3085         raw_spin_unlock(&kvm_count_lock);
3086 }
3087
3088 static int hardware_enable_all(void)
3089 {
3090         int r = 0;
3091
3092         raw_spin_lock(&kvm_count_lock);
3093
3094         kvm_usage_count++;
3095         if (kvm_usage_count == 1) {
3096                 atomic_set(&hardware_enable_failed, 0);
3097                 on_each_cpu(hardware_enable_nolock, NULL, 1);
3098
3099                 if (atomic_read(&hardware_enable_failed)) {
3100                         hardware_disable_all_nolock();
3101                         r = -EBUSY;
3102                 }
3103         }
3104
3105         raw_spin_unlock(&kvm_count_lock);
3106
3107         return r;
3108 }
3109
3110 static int kvm_cpu_hotplug(struct notifier_block *notifier, unsigned long val,
3111                            void *v)
3112 {
3113         val &= ~CPU_TASKS_FROZEN;
3114         switch (val) {
3115         case CPU_DYING:
3116                 hardware_disable();
3117                 break;
3118         case CPU_STARTING:
3119                 hardware_enable();
3120                 break;
3121         }
3122         return NOTIFY_OK;
3123 }
3124
3125 static int kvm_reboot(struct notifier_block *notifier, unsigned long val,
3126                       void *v)
3127 {
3128         /*
3129          * Some (well, at least mine) BIOSes hang on reboot if
3130          * in vmx root mode.
3131          *
3132          * And Intel TXT required VMX off for all cpu when system shutdown.
3133          */
3134         pr_info("kvm: exiting hardware virtualization\n");
3135         kvm_rebooting = true;
3136         on_each_cpu(hardware_disable_nolock, NULL, 1);
3137         return NOTIFY_OK;
3138 }
3139
3140 static struct notifier_block kvm_reboot_notifier = {
3141         .notifier_call = kvm_reboot,
3142         .priority = 0,
3143 };
3144
3145 static void kvm_io_bus_destroy(struct kvm_io_bus *bus)
3146 {
3147         int i;
3148
3149         for (i = 0; i < bus->dev_count; i++) {
3150                 struct kvm_io_device *pos = bus->range[i].dev;
3151
3152                 kvm_iodevice_destructor(pos);
3153         }
3154         kfree(bus);
3155 }
3156
3157 static inline int kvm_io_bus_cmp(const struct kvm_io_range *r1,
3158                                  const struct kvm_io_range *r2)
3159 {
3160         if (r1->addr < r2->addr)
3161                 return -1;
3162         if (r1->addr + r1->len > r2->addr + r2->len)
3163                 return 1;
3164         return 0;
3165 }
3166
3167 static int kvm_io_bus_sort_cmp(const void *p1, const void *p2)
3168 {
3169         return kvm_io_bus_cmp(p1, p2);
3170 }
3171
3172 static int kvm_io_bus_insert_dev(struct kvm_io_bus *bus, struct kvm_io_device *dev,
3173                           gpa_t addr, int len)
3174 {
3175         bus->range[bus->dev_count++] = (struct kvm_io_range) {
3176                 .addr = addr,
3177                 .len = len,
3178                 .dev = dev,
3179         };
3180
3181         sort(bus->range, bus->dev_count, sizeof(struct kvm_io_range),
3182                 kvm_io_bus_sort_cmp, NULL);
3183
3184         return 0;
3185 }
3186
3187 static int kvm_io_bus_get_first_dev(struct kvm_io_bus *bus,
3188                              gpa_t addr, int len)
3189 {
3190         struct kvm_io_range *range, key;
3191         int off;
3192
3193         key = (struct kvm_io_range) {
3194                 .addr = addr,
3195                 .len = len,
3196         };
3197
3198         range = bsearch(&key, bus->range, bus->dev_count,
3199                         sizeof(struct kvm_io_range), kvm_io_bus_sort_cmp);
3200         if (range == NULL)
3201                 return -ENOENT;
3202
3203         off = range - bus->range;
3204
3205         while (off > 0 && kvm_io_bus_cmp(&key, &bus->range[off-1]) == 0)
3206                 off--;
3207
3208         return off;
3209 }
3210
3211 static int __kvm_io_bus_write(struct kvm_vcpu *vcpu, struct kvm_io_bus *bus,
3212                               struct kvm_io_range *range, const void *val)
3213 {
3214         int idx;
3215
3216         idx = kvm_io_bus_get_first_dev(bus, range->addr, range->len);
3217         if (idx < 0)
3218                 return -EOPNOTSUPP;
3219
3220         while (idx < bus->dev_count &&
3221                 kvm_io_bus_cmp(range, &bus->range[idx]) == 0) {
3222                 if (!kvm_iodevice_write(vcpu, bus->range[idx].dev, range->addr,
3223                                         range->len, val))
3224                         return idx;
3225                 idx++;
3226         }
3227
3228         return -EOPNOTSUPP;
3229 }
3230
3231 /* kvm_io_bus_write - called under kvm->slots_lock */
3232 int kvm_io_bus_write(struct kvm_vcpu *vcpu, enum kvm_bus bus_idx, gpa_t addr,
3233                      int len, const void *val)
3234 {
3235         struct kvm_io_bus *bus;
3236         struct kvm_io_range range;
3237         int r;
3238
3239         range = (struct kvm_io_range) {
3240                 .addr = addr,
3241                 .len = len,
3242         };
3243
3244         bus = srcu_dereference(vcpu->kvm->buses[bus_idx], &vcpu->kvm->srcu);
3245         r = __kvm_io_bus_write(vcpu, bus, &range, val);
3246         return r < 0 ? r : 0;
3247 }
3248
3249 /* kvm_io_bus_write_cookie - called under kvm->slots_lock */
3250 int kvm_io_bus_write_cookie(struct kvm_vcpu *vcpu, enum kvm_bus bus_idx,
3251                             gpa_t addr, int len, const void *val, long cookie)
3252 {
3253         struct kvm_io_bus *bus;
3254         struct kvm_io_range range;
3255
3256         range = (struct kvm_io_range) {
3257                 .addr = addr,
3258                 .len = len,
3259         };
3260
3261         bus = srcu_dereference(vcpu->kvm->buses[bus_idx], &vcpu->kvm->srcu);
3262
3263         /* First try the device referenced by cookie. */
3264         if ((cookie >= 0) && (cookie < bus->dev_count) &&
3265             (kvm_io_bus_cmp(&range, &bus->range[cookie]) == 0))
3266                 if (!kvm_iodevice_write(vcpu, bus->range[cookie].dev, addr, len,
3267                                         val))
3268                         return cookie;
3269
3270         /*
3271          * cookie contained garbage; fall back to search and return the
3272          * correct cookie value.
3273          */
3274         return __kvm_io_bus_write(vcpu, bus, &range, val);
3275 }
3276
3277 static int __kvm_io_bus_read(struct kvm_vcpu *vcpu, struct kvm_io_bus *bus,
3278                              struct kvm_io_range *range, void *val)
3279 {
3280         int idx;
3281
3282         idx = kvm_io_bus_get_first_dev(bus, range->addr, range->len);
3283         if (idx < 0)
3284                 return -EOPNOTSUPP;
3285
3286         while (idx < bus->dev_count &&
3287                 kvm_io_bus_cmp(range, &bus->range[idx]) == 0) {
3288                 if (!kvm_iodevice_read(vcpu, bus->range[idx].dev, range->addr,
3289                                        range->len, val))
3290                         return idx;
3291                 idx++;
3292         }
3293
3294         return -EOPNOTSUPP;
3295 }
3296 EXPORT_SYMBOL_GPL(kvm_io_bus_write);
3297
3298 /* kvm_io_bus_read - called under kvm->slots_lock */
3299 int kvm_io_bus_read(struct kvm_vcpu *vcpu, enum kvm_bus bus_idx, gpa_t addr,
3300                     int len, void *val)
3301 {
3302         struct kvm_io_bus *bus;
3303         struct kvm_io_range range;
3304         int r;
3305
3306         range = (struct kvm_io_range) {
3307                 .addr = addr,
3308                 .len = len,
3309         };
3310
3311         bus = srcu_dereference(vcpu->kvm->buses[bus_idx], &vcpu->kvm->srcu);
3312         r = __kvm_io_bus_read(vcpu, bus, &range, val);
3313         return r < 0 ? r : 0;
3314 }
3315
3316
3317 /* Caller must hold slots_lock. */
3318 int kvm_io_bus_register_dev(struct kvm *kvm, enum kvm_bus bus_idx, gpa_t addr,
3319                             int len, struct kvm_io_device *dev)
3320 {
3321         struct kvm_io_bus *new_bus, *bus;
3322
3323         bus = kvm->buses[bus_idx];
3324         /* exclude ioeventfd which is limited by maximum fd */
3325         if (bus->dev_count - bus->ioeventfd_count > NR_IOBUS_DEVS - 1)
3326                 return -ENOSPC;
3327
3328         new_bus = kzalloc(sizeof(*bus) + ((bus->dev_count + 1) *
3329                           sizeof(struct kvm_io_range)), GFP_KERNEL);
3330         if (!new_bus)
3331                 return -ENOMEM;
3332         memcpy(new_bus, bus, sizeof(*bus) + (bus->dev_count *
3333                sizeof(struct kvm_io_range)));
3334         kvm_io_bus_insert_dev(new_bus, dev, addr, len);
3335         rcu_assign_pointer(kvm->buses[bus_idx], new_bus);
3336         synchronize_srcu_expedited(&kvm->srcu);
3337         kfree(bus);
3338
3339         return 0;
3340 }
3341
3342 /* Caller must hold slots_lock. */
3343 int kvm_io_bus_unregister_dev(struct kvm *kvm, enum kvm_bus bus_idx,
3344                               struct kvm_io_device *dev)
3345 {
3346         int i, r;
3347         struct kvm_io_bus *new_bus, *bus;
3348
3349         bus = kvm->buses[bus_idx];
3350         r = -ENOENT;
3351         for (i = 0; i < bus->dev_count; i++)
3352                 if (bus->range[i].dev == dev) {
3353                         r = 0;
3354                         break;
3355                 }
3356
3357         if (r)
3358                 return r;
3359
3360         new_bus = kzalloc(sizeof(*bus) + ((bus->dev_count - 1) *
3361                           sizeof(struct kvm_io_range)), GFP_KERNEL);
3362         if (!new_bus)
3363                 return -ENOMEM;
3364
3365         memcpy(new_bus, bus, sizeof(*bus) + i * sizeof(struct kvm_io_range));
3366         new_bus->dev_count--;
3367         memcpy(new_bus->range + i, bus->range + i + 1,
3368                (new_bus->dev_count - i) * sizeof(struct kvm_io_range));
3369
3370         rcu_assign_pointer(kvm->buses[bus_idx], new_bus);
3371         synchronize_srcu_expedited(&kvm->srcu);
3372         kfree(bus);
3373         return r;
3374 }
3375
3376 static struct notifier_block kvm_cpu_notifier = {
3377         .notifier_call = kvm_cpu_hotplug,
3378 };
3379
3380 static int vm_stat_get(void *_offset, u64 *val)
3381 {
3382         unsigned offset = (long)_offset;
3383         struct kvm *kvm;
3384
3385         *val = 0;
3386         spin_lock(&kvm_lock);
3387         list_for_each_entry(kvm, &vm_list, vm_list)
3388                 *val += *(u32 *)((void *)kvm + offset);
3389         spin_unlock(&kvm_lock);
3390         return 0;
3391 }
3392
3393 DEFINE_SIMPLE_ATTRIBUTE(vm_stat_fops, vm_stat_get, NULL, "%llu\n");
3394
3395 static int vcpu_stat_get(void *_offset, u64 *val)
3396 {
3397         unsigned offset = (long)_offset;
3398         struct kvm *kvm;
3399         struct kvm_vcpu *vcpu;
3400         int i;
3401
3402         *val = 0;
3403         spin_lock(&kvm_lock);
3404         list_for_each_entry(kvm, &vm_list, vm_list)
3405                 kvm_for_each_vcpu(i, vcpu, kvm)
3406                         *val += *(u32 *)((void *)vcpu + offset);
3407
3408         spin_unlock(&kvm_lock);
3409         return 0;
3410 }
3411
3412 DEFINE_SIMPLE_ATTRIBUTE(vcpu_stat_fops, vcpu_stat_get, NULL, "%llu\n");
3413
3414 static const struct file_operations *stat_fops[] = {
3415         [KVM_STAT_VCPU] = &vcpu_stat_fops,
3416         [KVM_STAT_VM]   = &vm_stat_fops,
3417 };
3418
3419 static int kvm_init_debug(void)
3420 {
3421         int r = -EEXIST;
3422         struct kvm_stats_debugfs_item *p;
3423
3424         kvm_debugfs_dir = debugfs_create_dir("kvm", NULL);
3425         if (kvm_debugfs_dir == NULL)
3426                 goto out;
3427
3428         for (p = debugfs_entries; p->name; ++p) {
3429                 p->dentry = debugfs_create_file(p->name, 0444, kvm_debugfs_dir,
3430                                                 (void *)(long)p->offset,
3431                                                 stat_fops[p->kind]);
3432                 if (p->dentry == NULL)
3433                         goto out_dir;
3434         }
3435
3436         return 0;
3437
3438 out_dir:
3439         debugfs_remove_recursive(kvm_debugfs_dir);
3440 out:
3441         return r;
3442 }
3443
3444 static void kvm_exit_debug(void)
3445 {
3446         struct kvm_stats_debugfs_item *p;
3447
3448         for (p = debugfs_entries; p->name; ++p)
3449                 debugfs_remove(p->dentry);
3450         debugfs_remove(kvm_debugfs_dir);
3451 }
3452
3453 static int kvm_suspend(void)
3454 {
3455         if (kvm_usage_count)
3456                 hardware_disable_nolock(NULL);
3457         return 0;
3458 }
3459
3460 static void kvm_resume(void)
3461 {
3462         if (kvm_usage_count) {
3463                 WARN_ON(raw_spin_is_locked(&kvm_count_lock));
3464                 hardware_enable_nolock(NULL);
3465         }
3466 }
3467
3468 static struct syscore_ops kvm_syscore_ops = {
3469         .suspend = kvm_suspend,
3470         .resume = kvm_resume,
3471 };
3472
3473 static inline
3474 struct kvm_vcpu *preempt_notifier_to_vcpu(struct preempt_notifier *pn)
3475 {
3476         return container_of(pn, struct kvm_vcpu, preempt_notifier);
3477 }
3478
3479 static void kvm_sched_in(struct preempt_notifier *pn, int cpu)
3480 {
3481         struct kvm_vcpu *vcpu = preempt_notifier_to_vcpu(pn);
3482
3483         if (vcpu->preempted)
3484                 vcpu->preempted = false;
3485
3486         kvm_arch_sched_in(vcpu, cpu);
3487
3488         kvm_arch_vcpu_load(vcpu, cpu);
3489 }
3490
3491 static void kvm_sched_out(struct preempt_notifier *pn,
3492                           struct task_struct *next)
3493 {
3494         struct kvm_vcpu *vcpu = preempt_notifier_to_vcpu(pn);
3495
3496         if (current->state == TASK_RUNNING)
3497                 vcpu->preempted = true;
3498         kvm_arch_vcpu_put(vcpu);
3499 }
3500
3501 int kvm_init(void *opaque, unsigned vcpu_size, unsigned vcpu_align,
3502                   struct module *module)
3503 {
3504         int r;
3505         int cpu;
3506
3507         r = kvm_arch_init(opaque);
3508         if (r)
3509                 goto out_fail;
3510
3511         /*
3512          * kvm_arch_init makes sure there's at most one caller
3513          * for architectures that support multiple implementations,
3514          * like intel and amd on x86.
3515          * kvm_arch_init must be called before kvm_irqfd_init to avoid creating
3516          * conflicts in case kvm is already setup for another implementation.
3517          */
3518         r = kvm_irqfd_init();
3519         if (r)
3520                 goto out_irqfd;
3521
3522         if (!zalloc_cpumask_var(&cpus_hardware_enabled, GFP_KERNEL)) {
3523                 r = -ENOMEM;
3524                 goto out_free_0;
3525         }
3526
3527         r = kvm_arch_hardware_setup();
3528         if (r < 0)
3529                 goto out_free_0a;
3530
3531         for_each_online_cpu(cpu) {
3532                 smp_call_function_single(cpu,
3533                                 kvm_arch_check_processor_compat,
3534                                 &r, 1);
3535                 if (r < 0)
3536                         goto out_free_1;
3537         }
3538
3539         r = register_cpu_notifier(&kvm_cpu_notifier);
3540         if (r)
3541                 goto out_free_2;
3542         register_reboot_notifier(&kvm_reboot_notifier);
3543
3544         /* A kmem cache lets us meet the alignment requirements of fx_save. */
3545         if (!vcpu_align)
3546                 vcpu_align = __alignof__(struct kvm_vcpu);
3547         kvm_vcpu_cache = kmem_cache_create("kvm_vcpu", vcpu_size, vcpu_align,
3548                                            0, NULL);
3549         if (!kvm_vcpu_cache) {
3550                 r = -ENOMEM;
3551                 goto out_free_3;
3552         }
3553
3554         r = kvm_async_pf_init();
3555         if (r)
3556                 goto out_free;
3557
3558         kvm_chardev_ops.owner = module;
3559         kvm_vm_fops.owner = module;
3560         kvm_vcpu_fops.owner = module;
3561
3562         r = misc_register(&kvm_dev);
3563         if (r) {
3564                 pr_err("kvm: misc device register failed\n");
3565                 goto out_unreg;
3566         }
3567
3568         register_syscore_ops(&kvm_syscore_ops);
3569
3570         kvm_preempt_ops.sched_in = kvm_sched_in;
3571         kvm_preempt_ops.sched_out = kvm_sched_out;
3572
3573         r = kvm_init_debug();
3574         if (r) {
3575                 pr_err("kvm: create debugfs files failed\n");
3576                 goto out_undebugfs;
3577         }
3578
3579         r = kvm_vfio_ops_init();
3580         WARN_ON(r);
3581
3582         return 0;
3583
3584 out_undebugfs:
3585         unregister_syscore_ops(&kvm_syscore_ops);
3586         misc_deregister(&kvm_dev);
3587 out_unreg:
3588         kvm_async_pf_deinit();
3589 out_free:
3590         kmem_cache_destroy(kvm_vcpu_cache);
3591 out_free_3:
3592         unregister_reboot_notifier(&kvm_reboot_notifier);
3593         unregister_cpu_notifier(&kvm_cpu_notifier);
3594 out_free_2:
3595 out_free_1:
3596         kvm_arch_hardware_unsetup();
3597 out_free_0a:
3598         free_cpumask_var(cpus_hardware_enabled);
3599 out_free_0:
3600         kvm_irqfd_exit();
3601 out_irqfd:
3602         kvm_arch_exit();
3603 out_fail:
3604         return r;
3605 }
3606 EXPORT_SYMBOL_GPL(kvm_init);
3607
3608 void kvm_exit(void)
3609 {
3610         kvm_exit_debug();
3611         misc_deregister(&kvm_dev);
3612         kmem_cache_destroy(kvm_vcpu_cache);
3613         kvm_async_pf_deinit();
3614         unregister_syscore_ops(&kvm_syscore_ops);
3615         unregister_reboot_notifier(&kvm_reboot_notifier);
3616         unregister_cpu_notifier(&kvm_cpu_notifier);
3617         on_each_cpu(hardware_disable_nolock, NULL, 1);
3618         kvm_arch_hardware_unsetup();
3619         kvm_arch_exit();
3620         kvm_irqfd_exit();
3621         free_cpumask_var(cpus_hardware_enabled);
3622         kvm_vfio_ops_exit();
3623 }
3624 EXPORT_SYMBOL_GPL(kvm_exit);