linux/virt/kvm/kvm_main.c
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   1/*
   2 * Kernel-based Virtual Machine driver for Linux
   3 *
   4 * This module enables machines with Intel VT-x extensions to run virtual
   5 * machines without emulation or binary translation.
   6 *
   7 * Copyright (C) 2006 Qumranet, Inc.
   8 * Copyright 2010 Red Hat, Inc. and/or its affiliates.
   9 *
  10 * Authors:
  11 *   Avi Kivity   <avi@qumranet.com>
  12 *   Yaniv Kamay  <yaniv@qumranet.com>
  13 *
  14 * This work is licensed under the terms of the GNU GPL, version 2.  See
  15 * the COPYING file in the top-level directory.
  16 *
  17 */
  18
  19#include "iodev.h"
  20
  21#include <linux/kvm_host.h>
  22#include <linux/kvm.h>
  23#include <linux/module.h>
  24#include <linux/errno.h>
  25#include <linux/percpu.h>
  26#include <linux/mm.h>
  27#include <linux/miscdevice.h>
  28#include <linux/vmalloc.h>
  29#include <linux/reboot.h>
  30#include <linux/debugfs.h>
  31#include <linux/highmem.h>
  32#include <linux/file.h>
  33#include <linux/syscore_ops.h>
  34#include <linux/cpu.h>
  35#include <linux/sched.h>
  36#include <linux/cpumask.h>
  37#include <linux/smp.h>
  38#include <linux/anon_inodes.h>
  39#include <linux/profile.h>
  40#include <linux/kvm_para.h>
  41#include <linux/pagemap.h>
  42#include <linux/mman.h>
  43#include <linux/swap.h>
  44#include <linux/bitops.h>
  45#include <linux/spinlock.h>
  46#include <linux/compat.h>
  47#include <linux/srcu.h>
  48#include <linux/hugetlb.h>
  49#include <linux/slab.h>
  50#include <linux/sort.h>
  51#include <linux/bsearch.h>
  52
  53#include <asm/processor.h>
  54#include <asm/io.h>
  55#include <asm/uaccess.h>
  56#include <asm/pgtable.h>
  57
  58#include "coalesced_mmio.h"
  59#include "async_pf.h"
  60
  61#define CREATE_TRACE_POINTS
  62#include <trace/events/kvm.h>
  63
  64MODULE_AUTHOR("Qumranet");
  65MODULE_LICENSE("GPL");
  66
  67/*
  68 * Ordering of locks:
  69 *
  70 *              kvm->lock --> kvm->slots_lock --> kvm->irq_lock
  71 */
  72
  73DEFINE_RAW_SPINLOCK(kvm_lock);
  74LIST_HEAD(vm_list);
  75
  76static cpumask_var_t cpus_hardware_enabled;
  77static int kvm_usage_count = 0;
  78static atomic_t hardware_enable_failed;
  79
  80struct kmem_cache *kvm_vcpu_cache;
  81EXPORT_SYMBOL_GPL(kvm_vcpu_cache);
  82
  83static __read_mostly struct preempt_ops kvm_preempt_ops;
  84
  85struct dentry *kvm_debugfs_dir;
  86
  87static long kvm_vcpu_ioctl(struct file *file, unsigned int ioctl,
  88                           unsigned long arg);
  89#ifdef CONFIG_COMPAT
  90static long kvm_vcpu_compat_ioctl(struct file *file, unsigned int ioctl,
  91                                  unsigned long arg);
  92#endif
  93static int hardware_enable_all(void);
  94static void hardware_disable_all(void);
  95
  96static void kvm_io_bus_destroy(struct kvm_io_bus *bus);
  97
  98bool kvm_rebooting;
  99EXPORT_SYMBOL_GPL(kvm_rebooting);
 100
 101static bool largepages_enabled = true;
 102
 103bool kvm_is_mmio_pfn(pfn_t pfn)
 104{
 105        if (pfn_valid(pfn)) {
 106                int reserved;
 107                struct page *tail = pfn_to_page(pfn);
 108                struct page *head = compound_trans_head(tail);
 109                reserved = PageReserved(head);
 110                if (head != tail) {
 111                        /*
 112                         * "head" is not a dangling pointer
 113                         * (compound_trans_head takes care of that)
 114                         * but the hugepage may have been splitted
 115                         * from under us (and we may not hold a
 116                         * reference count on the head page so it can
 117                         * be reused before we run PageReferenced), so
 118                         * we've to check PageTail before returning
 119                         * what we just read.
 120                         */
 121                        smp_rmb();
 122                        if (PageTail(tail))
 123                                return reserved;
 124                }
 125                return PageReserved(tail);
 126        }
 127
 128        return true;
 129}
 130
 131/*
 132 * Switches to specified vcpu, until a matching vcpu_put()
 133 */
 134int vcpu_load(struct kvm_vcpu *vcpu)
 135{
 136        int cpu;
 137
 138        if (mutex_lock_killable(&vcpu->mutex))
 139                return -EINTR;
 140        if (unlikely(vcpu->pid != current->pids[PIDTYPE_PID].pid)) {
 141                /* The thread running this VCPU changed. */
 142                struct pid *oldpid = vcpu->pid;
 143                struct pid *newpid = get_task_pid(current, PIDTYPE_PID);
 144                rcu_assign_pointer(vcpu->pid, newpid);
 145                synchronize_rcu();
 146                put_pid(oldpid);
 147        }
 148        cpu = get_cpu();
 149        preempt_notifier_register(&vcpu->preempt_notifier);
 150        kvm_arch_vcpu_load(vcpu, cpu);
 151        put_cpu();
 152        return 0;
 153}
 154
 155void vcpu_put(struct kvm_vcpu *vcpu)
 156{
 157        preempt_disable();
 158        kvm_arch_vcpu_put(vcpu);
 159        preempt_notifier_unregister(&vcpu->preempt_notifier);
 160        preempt_enable();
 161        mutex_unlock(&vcpu->mutex);
 162}
 163
 164static void ack_flush(void *_completed)
 165{
 166}
 167
 168static bool make_all_cpus_request(struct kvm *kvm, unsigned int req)
 169{
 170        int i, cpu, me;
 171        cpumask_var_t cpus;
 172        bool called = true;
 173        struct kvm_vcpu *vcpu;
 174
 175        zalloc_cpumask_var(&cpus, GFP_ATOMIC);
 176
 177        me = get_cpu();
 178        kvm_for_each_vcpu(i, vcpu, kvm) {
 179                kvm_make_request(req, vcpu);
 180                cpu = vcpu->cpu;
 181
 182                /* Set ->requests bit before we read ->mode */
 183                smp_mb();
 184
 185                if (cpus != NULL && cpu != -1 && cpu != me &&
 186                      kvm_vcpu_exiting_guest_mode(vcpu) != OUTSIDE_GUEST_MODE)
 187                        cpumask_set_cpu(cpu, cpus);
 188        }
 189        if (unlikely(cpus == NULL))
 190                smp_call_function_many(cpu_online_mask, ack_flush, NULL, 1);
 191        else if (!cpumask_empty(cpus))
 192                smp_call_function_many(cpus, ack_flush, NULL, 1);
 193        else
 194                called = false;
 195        put_cpu();
 196        free_cpumask_var(cpus);
 197        return called;
 198}
 199
 200void kvm_flush_remote_tlbs(struct kvm *kvm)
 201{
 202        long dirty_count = kvm->tlbs_dirty;
 203
 204        smp_mb();
 205        if (make_all_cpus_request(kvm, KVM_REQ_TLB_FLUSH))
 206                ++kvm->stat.remote_tlb_flush;
 207        cmpxchg(&kvm->tlbs_dirty, dirty_count, 0);
 208}
 209
 210void kvm_reload_remote_mmus(struct kvm *kvm)
 211{
 212        make_all_cpus_request(kvm, KVM_REQ_MMU_RELOAD);
 213}
 214
 215int kvm_vcpu_init(struct kvm_vcpu *vcpu, struct kvm *kvm, unsigned id)
 216{
 217        struct page *page;
 218        int r;
 219
 220        mutex_init(&vcpu->mutex);
 221        vcpu->cpu = -1;
 222        vcpu->kvm = kvm;
 223        vcpu->vcpu_id = id;
 224        vcpu->pid = NULL;
 225        init_waitqueue_head(&vcpu->wq);
 226        kvm_async_pf_vcpu_init(vcpu);
 227
 228        page = alloc_page(GFP_KERNEL | __GFP_ZERO);
 229        if (!page) {
 230                r = -ENOMEM;
 231                goto fail;
 232        }
 233        vcpu->run = page_address(page);
 234
 235        kvm_vcpu_set_in_spin_loop(vcpu, false);
 236        kvm_vcpu_set_dy_eligible(vcpu, false);
 237
 238        r = kvm_arch_vcpu_init(vcpu);
 239        if (r < 0)
 240                goto fail_free_run;
 241        return 0;
 242
 243fail_free_run:
 244        free_page((unsigned long)vcpu->run);
 245fail:
 246        return r;
 247}
 248EXPORT_SYMBOL_GPL(kvm_vcpu_init);
 249
 250void kvm_vcpu_uninit(struct kvm_vcpu *vcpu)
 251{
 252        put_pid(vcpu->pid);
 253        kvm_arch_vcpu_uninit(vcpu);
 254        free_page((unsigned long)vcpu->run);
 255}
 256EXPORT_SYMBOL_GPL(kvm_vcpu_uninit);
 257
 258#if defined(CONFIG_MMU_NOTIFIER) && defined(KVM_ARCH_WANT_MMU_NOTIFIER)
 259static inline struct kvm *mmu_notifier_to_kvm(struct mmu_notifier *mn)
 260{
 261        return container_of(mn, struct kvm, mmu_notifier);
 262}
 263
 264static void kvm_mmu_notifier_invalidate_page(struct mmu_notifier *mn,
 265                                             struct mm_struct *mm,
 266                                             unsigned long address)
 267{
 268        struct kvm *kvm = mmu_notifier_to_kvm(mn);
 269        int need_tlb_flush, idx;
 270
 271        /*
 272         * When ->invalidate_page runs, the linux pte has been zapped
 273         * already but the page is still allocated until
 274         * ->invalidate_page returns. So if we increase the sequence
 275         * here the kvm page fault will notice if the spte can't be
 276         * established because the page is going to be freed. If
 277         * instead the kvm page fault establishes the spte before
 278         * ->invalidate_page runs, kvm_unmap_hva will release it
 279         * before returning.
 280         *
 281         * The sequence increase only need to be seen at spin_unlock
 282         * time, and not at spin_lock time.
 283         *
 284         * Increasing the sequence after the spin_unlock would be
 285         * unsafe because the kvm page fault could then establish the
 286         * pte after kvm_unmap_hva returned, without noticing the page
 287         * is going to be freed.
 288         */
 289        idx = srcu_read_lock(&kvm->srcu);
 290        spin_lock(&kvm->mmu_lock);
 291
 292        kvm->mmu_notifier_seq++;
 293        need_tlb_flush = kvm_unmap_hva(kvm, address) | kvm->tlbs_dirty;
 294        /* we've to flush the tlb before the pages can be freed */
 295        if (need_tlb_flush)
 296                kvm_flush_remote_tlbs(kvm);
 297
 298        spin_unlock(&kvm->mmu_lock);
 299        srcu_read_unlock(&kvm->srcu, idx);
 300}
 301
 302static void kvm_mmu_notifier_change_pte(struct mmu_notifier *mn,
 303                                        struct mm_struct *mm,
 304                                        unsigned long address,
 305                                        pte_t pte)
 306{
 307        struct kvm *kvm = mmu_notifier_to_kvm(mn);
 308        int idx;
 309
 310        idx = srcu_read_lock(&kvm->srcu);
 311        spin_lock(&kvm->mmu_lock);
 312        kvm->mmu_notifier_seq++;
 313        kvm_set_spte_hva(kvm, address, pte);
 314        spin_unlock(&kvm->mmu_lock);
 315        srcu_read_unlock(&kvm->srcu, idx);
 316}
 317
 318static void kvm_mmu_notifier_invalidate_range_start(struct mmu_notifier *mn,
 319                                                    struct mm_struct *mm,
 320                                                    unsigned long start,
 321                                                    unsigned long end)
 322{
 323        struct kvm *kvm = mmu_notifier_to_kvm(mn);
 324        int need_tlb_flush = 0, idx;
 325
 326        idx = srcu_read_lock(&kvm->srcu);
 327        spin_lock(&kvm->mmu_lock);
 328        /*
 329         * The count increase must become visible at unlock time as no
 330         * spte can be established without taking the mmu_lock and
 331         * count is also read inside the mmu_lock critical section.
 332         */
 333        kvm->mmu_notifier_count++;
 334        need_tlb_flush = kvm_unmap_hva_range(kvm, start, end);
 335        need_tlb_flush |= kvm->tlbs_dirty;
 336        /* we've to flush the tlb before the pages can be freed */
 337        if (need_tlb_flush)
 338                kvm_flush_remote_tlbs(kvm);
 339
 340        spin_unlock(&kvm->mmu_lock);
 341        srcu_read_unlock(&kvm->srcu, idx);
 342}
 343
 344static void kvm_mmu_notifier_invalidate_range_end(struct mmu_notifier *mn,
 345                                                  struct mm_struct *mm,
 346                                                  unsigned long start,
 347                                                  unsigned long end)
 348{
 349        struct kvm *kvm = mmu_notifier_to_kvm(mn);
 350
 351        spin_lock(&kvm->mmu_lock);
 352        /*
 353         * This sequence increase will notify the kvm page fault that
 354         * the page that is going to be mapped in the spte could have
 355         * been freed.
 356         */
 357        kvm->mmu_notifier_seq++;
 358        smp_wmb();
 359        /*
 360         * The above sequence increase must be visible before the
 361         * below count decrease, which is ensured by the smp_wmb above
 362         * in conjunction with the smp_rmb in mmu_notifier_retry().
 363         */
 364        kvm->mmu_notifier_count--;
 365        spin_unlock(&kvm->mmu_lock);
 366
 367        BUG_ON(kvm->mmu_notifier_count < 0);
 368}
 369
 370static int kvm_mmu_notifier_clear_flush_young(struct mmu_notifier *mn,
 371                                              struct mm_struct *mm,
 372                                              unsigned long address)
 373{
 374        struct kvm *kvm = mmu_notifier_to_kvm(mn);
 375        int young, idx;
 376
 377        idx = srcu_read_lock(&kvm->srcu);
 378        spin_lock(&kvm->mmu_lock);
 379
 380        young = kvm_age_hva(kvm, address);
 381        if (young)
 382                kvm_flush_remote_tlbs(kvm);
 383
 384        spin_unlock(&kvm->mmu_lock);
 385        srcu_read_unlock(&kvm->srcu, idx);
 386
 387        return young;
 388}
 389
 390static int kvm_mmu_notifier_test_young(struct mmu_notifier *mn,
 391                                       struct mm_struct *mm,
 392                                       unsigned long address)
 393{
 394        struct kvm *kvm = mmu_notifier_to_kvm(mn);
 395        int young, idx;
 396
 397        idx = srcu_read_lock(&kvm->srcu);
 398        spin_lock(&kvm->mmu_lock);
 399        young = kvm_test_age_hva(kvm, address);
 400        spin_unlock(&kvm->mmu_lock);
 401        srcu_read_unlock(&kvm->srcu, idx);
 402
 403        return young;
 404}
 405
 406static void kvm_mmu_notifier_release(struct mmu_notifier *mn,
 407                                     struct mm_struct *mm)
 408{
 409        struct kvm *kvm = mmu_notifier_to_kvm(mn);
 410        int idx;
 411
 412        idx = srcu_read_lock(&kvm->srcu);
 413        kvm_arch_flush_shadow_all(kvm);
 414        srcu_read_unlock(&kvm->srcu, idx);
 415}
 416
 417static const struct mmu_notifier_ops kvm_mmu_notifier_ops = {
 418        .invalidate_page        = kvm_mmu_notifier_invalidate_page,
 419        .invalidate_range_start = kvm_mmu_notifier_invalidate_range_start,
 420        .invalidate_range_end   = kvm_mmu_notifier_invalidate_range_end,
 421        .clear_flush_young      = kvm_mmu_notifier_clear_flush_young,
 422        .test_young             = kvm_mmu_notifier_test_young,
 423        .change_pte             = kvm_mmu_notifier_change_pte,
 424        .release                = kvm_mmu_notifier_release,
 425};
 426
 427static int kvm_init_mmu_notifier(struct kvm *kvm)
 428{
 429        kvm->mmu_notifier.ops = &kvm_mmu_notifier_ops;
 430        return mmu_notifier_register(&kvm->mmu_notifier, current->mm);
 431}
 432
 433#else  /* !(CONFIG_MMU_NOTIFIER && KVM_ARCH_WANT_MMU_NOTIFIER) */
 434
 435static int kvm_init_mmu_notifier(struct kvm *kvm)
 436{
 437        return 0;
 438}
 439
 440#endif /* CONFIG_MMU_NOTIFIER && KVM_ARCH_WANT_MMU_NOTIFIER */
 441
 442static void kvm_init_memslots_id(struct kvm *kvm)
 443{
 444        int i;
 445        struct kvm_memslots *slots = kvm->memslots;
 446
 447        for (i = 0; i < KVM_MEM_SLOTS_NUM; i++)
 448                slots->id_to_index[i] = slots->memslots[i].id = i;
 449}
 450
 451static struct kvm *kvm_create_vm(unsigned long type)
 452{
 453        int r, i;
 454        struct kvm *kvm = kvm_arch_alloc_vm();
 455
 456        if (!kvm)
 457                return ERR_PTR(-ENOMEM);
 458
 459        r = kvm_arch_init_vm(kvm, type);
 460        if (r)
 461                goto out_err_nodisable;
 462
 463        r = hardware_enable_all();
 464        if (r)
 465                goto out_err_nodisable;
 466
 467#ifdef CONFIG_HAVE_KVM_IRQCHIP
 468        INIT_HLIST_HEAD(&kvm->mask_notifier_list);
 469        INIT_HLIST_HEAD(&kvm->irq_ack_notifier_list);
 470#endif
 471
 472        r = -ENOMEM;
 473        kvm->memslots = kzalloc(sizeof(struct kvm_memslots), GFP_KERNEL);
 474        if (!kvm->memslots)
 475                goto out_err_nosrcu;
 476        kvm_init_memslots_id(kvm);
 477        if (init_srcu_struct(&kvm->srcu))
 478                goto out_err_nosrcu;
 479        for (i = 0; i < KVM_NR_BUSES; i++) {
 480                kvm->buses[i] = kzalloc(sizeof(struct kvm_io_bus),
 481                                        GFP_KERNEL);
 482                if (!kvm->buses[i])
 483                        goto out_err;
 484        }
 485
 486        spin_lock_init(&kvm->mmu_lock);
 487        kvm->mm = current->mm;
 488        atomic_inc(&kvm->mm->mm_count);
 489        kvm_eventfd_init(kvm);
 490        mutex_init(&kvm->lock);
 491        mutex_init(&kvm->irq_lock);
 492        mutex_init(&kvm->slots_lock);
 493        atomic_set(&kvm->users_count, 1);
 494
 495        r = kvm_init_mmu_notifier(kvm);
 496        if (r)
 497                goto out_err;
 498
 499        raw_spin_lock(&kvm_lock);
 500        list_add(&kvm->vm_list, &vm_list);
 501        raw_spin_unlock(&kvm_lock);
 502
 503        return kvm;
 504
 505out_err:
 506        cleanup_srcu_struct(&kvm->srcu);
 507out_err_nosrcu:
 508        hardware_disable_all();
 509out_err_nodisable:
 510        for (i = 0; i < KVM_NR_BUSES; i++)
 511                kfree(kvm->buses[i]);
 512        kfree(kvm->memslots);
 513        kvm_arch_free_vm(kvm);
 514        return ERR_PTR(r);
 515}
 516
 517/*
 518 * Avoid using vmalloc for a small buffer.
 519 * Should not be used when the size is statically known.
 520 */
 521void *kvm_kvzalloc(unsigned long size)
 522{
 523        if (size > PAGE_SIZE)
 524                return vzalloc(size);
 525        else
 526                return kzalloc(size, GFP_KERNEL);
 527}
 528
 529void kvm_kvfree(const void *addr)
 530{
 531        if (is_vmalloc_addr(addr))
 532                vfree(addr);
 533        else
 534                kfree(addr);
 535}
 536
 537static void kvm_destroy_dirty_bitmap(struct kvm_memory_slot *memslot)
 538{
 539        if (!memslot->dirty_bitmap)
 540                return;
 541
 542        kvm_kvfree(memslot->dirty_bitmap);
 543        memslot->dirty_bitmap = NULL;
 544}
 545
 546/*
 547 * Free any memory in @free but not in @dont.
 548 */
 549static void kvm_free_physmem_slot(struct kvm_memory_slot *free,
 550                                  struct kvm_memory_slot *dont)
 551{
 552        if (!dont || free->dirty_bitmap != dont->dirty_bitmap)
 553                kvm_destroy_dirty_bitmap(free);
 554
 555        kvm_arch_free_memslot(free, dont);
 556
 557        free->npages = 0;
 558}
 559
 560void kvm_free_physmem(struct kvm *kvm)
 561{
 562        struct kvm_memslots *slots = kvm->memslots;
 563        struct kvm_memory_slot *memslot;
 564
 565        kvm_for_each_memslot(memslot, slots)
 566                kvm_free_physmem_slot(memslot, NULL);
 567
 568        kfree(kvm->memslots);
 569}
 570
 571static void kvm_destroy_vm(struct kvm *kvm)
 572{
 573        int i;
 574        struct mm_struct *mm = kvm->mm;
 575
 576        kvm_arch_sync_events(kvm);
 577        raw_spin_lock(&kvm_lock);
 578        list_del(&kvm->vm_list);
 579        raw_spin_unlock(&kvm_lock);
 580        kvm_free_irq_routing(kvm);
 581        for (i = 0; i < KVM_NR_BUSES; i++)
 582                kvm_io_bus_destroy(kvm->buses[i]);
 583        kvm_coalesced_mmio_free(kvm);
 584#if defined(CONFIG_MMU_NOTIFIER) && defined(KVM_ARCH_WANT_MMU_NOTIFIER)
 585        mmu_notifier_unregister(&kvm->mmu_notifier, kvm->mm);
 586#else
 587        kvm_arch_flush_shadow_all(kvm);
 588#endif
 589        kvm_arch_destroy_vm(kvm);
 590        kvm_free_physmem(kvm);
 591        cleanup_srcu_struct(&kvm->srcu);
 592        kvm_arch_free_vm(kvm);
 593        hardware_disable_all();
 594        mmdrop(mm);
 595}
 596
 597void kvm_get_kvm(struct kvm *kvm)
 598{
 599        atomic_inc(&kvm->users_count);
 600}
 601EXPORT_SYMBOL_GPL(kvm_get_kvm);
 602
 603void kvm_put_kvm(struct kvm *kvm)
 604{
 605        if (atomic_dec_and_test(&kvm->users_count))
 606                kvm_destroy_vm(kvm);
 607}
 608EXPORT_SYMBOL_GPL(kvm_put_kvm);
 609
 610
 611static int kvm_vm_release(struct inode *inode, struct file *filp)
 612{
 613        struct kvm *kvm = filp->private_data;
 614
 615        kvm_irqfd_release(kvm);
 616
 617        kvm_put_kvm(kvm);
 618        return 0;
 619}
 620
 621/*
 622 * Allocation size is twice as large as the actual dirty bitmap size.
 623 * See x86's kvm_vm_ioctl_get_dirty_log() why this is needed.
 624 */
 625static int kvm_create_dirty_bitmap(struct kvm_memory_slot *memslot)
 626{
 627#ifndef CONFIG_S390
 628        unsigned long dirty_bytes = 2 * kvm_dirty_bitmap_bytes(memslot);
 629
 630        memslot->dirty_bitmap = kvm_kvzalloc(dirty_bytes);
 631        if (!memslot->dirty_bitmap)
 632                return -ENOMEM;
 633
 634#endif /* !CONFIG_S390 */
 635        return 0;
 636}
 637
 638static int cmp_memslot(const void *slot1, const void *slot2)
 639{
 640        struct kvm_memory_slot *s1, *s2;
 641
 642        s1 = (struct kvm_memory_slot *)slot1;
 643        s2 = (struct kvm_memory_slot *)slot2;
 644
 645        if (s1->npages < s2->npages)
 646                return 1;
 647        if (s1->npages > s2->npages)
 648                return -1;
 649
 650        return 0;
 651}
 652
 653/*
 654 * Sort the memslots base on its size, so the larger slots
 655 * will get better fit.
 656 */
 657static void sort_memslots(struct kvm_memslots *slots)
 658{
 659        int i;
 660
 661        sort(slots->memslots, KVM_MEM_SLOTS_NUM,
 662              sizeof(struct kvm_memory_slot), cmp_memslot, NULL);
 663
 664        for (i = 0; i < KVM_MEM_SLOTS_NUM; i++)
 665                slots->id_to_index[slots->memslots[i].id] = i;
 666}
 667
 668void update_memslots(struct kvm_memslots *slots, struct kvm_memory_slot *new)
 669{
 670        if (new) {
 671                int id = new->id;
 672                struct kvm_memory_slot *old = id_to_memslot(slots, id);
 673                unsigned long npages = old->npages;
 674
 675                *old = *new;
 676                if (new->npages != npages)
 677                        sort_memslots(slots);
 678        }
 679
 680        slots->generation++;
 681}
 682
 683static int check_memory_region_flags(struct kvm_userspace_memory_region *mem)
 684{
 685        u32 valid_flags = KVM_MEM_LOG_DIRTY_PAGES;
 686
 687#ifdef KVM_CAP_READONLY_MEM
 688        valid_flags |= KVM_MEM_READONLY;
 689#endif
 690
 691        if (mem->flags & ~valid_flags)
 692                return -EINVAL;
 693
 694        return 0;
 695}
 696
 697/*
 698 * Allocate some memory and give it an address in the guest physical address
 699 * space.
 700 *
 701 * Discontiguous memory is allowed, mostly for framebuffers.
 702 *
 703 * Must be called holding mmap_sem for write.
 704 */
 705int __kvm_set_memory_region(struct kvm *kvm,
 706                            struct kvm_userspace_memory_region *mem,
 707                            int user_alloc)
 708{
 709        int r;
 710        gfn_t base_gfn;
 711        unsigned long npages;
 712        unsigned long i;
 713        struct kvm_memory_slot *memslot;
 714        struct kvm_memory_slot old, new;
 715        struct kvm_memslots *slots, *old_memslots;
 716
 717        r = check_memory_region_flags(mem);
 718        if (r)
 719                goto out;
 720
 721        r = -EINVAL;
 722        /* General sanity checks */
 723        if (mem->memory_size & (PAGE_SIZE - 1))
 724                goto out;
 725        if (mem->guest_phys_addr & (PAGE_SIZE - 1))
 726                goto out;
 727        /* We can read the guest memory with __xxx_user() later on. */
 728        if (user_alloc &&
 729            ((mem->userspace_addr & (PAGE_SIZE - 1)) ||
 730             !access_ok(VERIFY_WRITE,
 731                        (void __user *)(unsigned long)mem->userspace_addr,
 732                        mem->memory_size)))
 733                goto out;
 734        if (mem->slot >= KVM_MEM_SLOTS_NUM)
 735                goto out;
 736        if (mem->guest_phys_addr + mem->memory_size < mem->guest_phys_addr)
 737                goto out;
 738
 739        memslot = id_to_memslot(kvm->memslots, mem->slot);
 740        base_gfn = mem->guest_phys_addr >> PAGE_SHIFT;
 741        npages = mem->memory_size >> PAGE_SHIFT;
 742
 743        r = -EINVAL;
 744        if (npages > KVM_MEM_MAX_NR_PAGES)
 745                goto out;
 746
 747        if (!npages)
 748                mem->flags &= ~KVM_MEM_LOG_DIRTY_PAGES;
 749
 750        new = old = *memslot;
 751
 752        new.id = mem->slot;
 753        new.base_gfn = base_gfn;
 754        new.npages = npages;
 755        new.flags = mem->flags;
 756
 757        /* Disallow changing a memory slot's size. */
 758        r = -EINVAL;
 759        if (npages && old.npages && npages != old.npages)
 760                goto out_free;
 761
 762        /* Check for overlaps */
 763        r = -EEXIST;
 764        for (i = 0; i < KVM_MEMORY_SLOTS; ++i) {
 765                struct kvm_memory_slot *s = &kvm->memslots->memslots[i];
 766
 767                if (s == memslot || !s->npages)
 768                        continue;
 769                if (!((base_gfn + npages <= s->base_gfn) ||
 770                      (base_gfn >= s->base_gfn + s->npages)))
 771                        goto out_free;
 772        }
 773
 774        /* Free page dirty bitmap if unneeded */
 775        if (!(new.flags & KVM_MEM_LOG_DIRTY_PAGES))
 776                new.dirty_bitmap = NULL;
 777
 778        r = -ENOMEM;
 779
 780        /* Allocate if a slot is being created */
 781        if (npages && !old.npages) {
 782                new.user_alloc = user_alloc;
 783                new.userspace_addr = mem->userspace_addr;
 784
 785                if (kvm_arch_create_memslot(&new, npages))
 786                        goto out_free;
 787        }
 788
 789        /* Allocate page dirty bitmap if needed */
 790        if ((new.flags & KVM_MEM_LOG_DIRTY_PAGES) && !new.dirty_bitmap) {
 791                if (kvm_create_dirty_bitmap(&new) < 0)
 792                        goto out_free;
 793                /* destroy any largepage mappings for dirty tracking */
 794        }
 795
 796        if (!npages || base_gfn != old.base_gfn) {
 797                struct kvm_memory_slot *slot;
 798
 799                r = -ENOMEM;
 800                slots = kmemdup(kvm->memslots, sizeof(struct kvm_memslots),
 801                                GFP_KERNEL);
 802                if (!slots)
 803                        goto out_free;
 804                slot = id_to_memslot(slots, mem->slot);
 805                slot->flags |= KVM_MEMSLOT_INVALID;
 806
 807                update_memslots(slots, NULL);
 808
 809                old_memslots = kvm->memslots;
 810                rcu_assign_pointer(kvm->memslots, slots);
 811                synchronize_srcu_expedited(&kvm->srcu);
 812                /* From this point no new shadow pages pointing to a deleted,
 813                 * or moved, memslot will be created.
 814                 *
 815                 * validation of sp->gfn happens in:
 816                 *      - gfn_to_hva (kvm_read_guest, gfn_to_pfn)
 817                 *      - kvm_is_visible_gfn (mmu_check_roots)
 818                 */
 819                kvm_arch_flush_shadow_memslot(kvm, slot);
 820                kfree(old_memslots);
 821        }
 822
 823        r = kvm_arch_prepare_memory_region(kvm, &new, old, mem, user_alloc);
 824        if (r)
 825                goto out_free;
 826
 827        /* map/unmap the pages in iommu page table */
 828        if (npages) {
 829                r = kvm_iommu_map_pages(kvm, &new);
 830                if (r)
 831                        goto out_free;
 832        } else
 833                kvm_iommu_unmap_pages(kvm, &old);
 834
 835        r = -ENOMEM;
 836        slots = kmemdup(kvm->memslots, sizeof(struct kvm_memslots),
 837                        GFP_KERNEL);
 838        if (!slots)
 839                goto out_free;
 840
 841        /* actual memory is freed via old in kvm_free_physmem_slot below */
 842        if (!npages) {
 843                new.dirty_bitmap = NULL;
 844                memset(&new.arch, 0, sizeof(new.arch));
 845        }
 846
 847        update_memslots(slots, &new);
 848        old_memslots = kvm->memslots;
 849        rcu_assign_pointer(kvm->memslots, slots);
 850        synchronize_srcu_expedited(&kvm->srcu);
 851
 852        kvm_arch_commit_memory_region(kvm, mem, old, user_alloc);
 853
 854        kvm_free_physmem_slot(&old, &new);
 855        kfree(old_memslots);
 856
 857        return 0;
 858
 859out_free:
 860        kvm_free_physmem_slot(&new, &old);
 861out:
 862        return r;
 863
 864}
 865EXPORT_SYMBOL_GPL(__kvm_set_memory_region);
 866
 867int kvm_set_memory_region(struct kvm *kvm,
 868                          struct kvm_userspace_memory_region *mem,
 869                          int user_alloc)
 870{
 871        int r;
 872
 873        mutex_lock(&kvm->slots_lock);
 874        r = __kvm_set_memory_region(kvm, mem, user_alloc);
 875        mutex_unlock(&kvm->slots_lock);
 876        return r;
 877}
 878EXPORT_SYMBOL_GPL(kvm_set_memory_region);
 879
 880int kvm_vm_ioctl_set_memory_region(struct kvm *kvm,
 881                                   struct
 882                                   kvm_userspace_memory_region *mem,
 883                                   int user_alloc)
 884{
 885        if (mem->slot >= KVM_MEMORY_SLOTS)
 886                return -EINVAL;
 887        return kvm_set_memory_region(kvm, mem, user_alloc);
 888}
 889
 890int kvm_get_dirty_log(struct kvm *kvm,
 891                        struct kvm_dirty_log *log, int *is_dirty)
 892{
 893        struct kvm_memory_slot *memslot;
 894        int r, i;
 895        unsigned long n;
 896        unsigned long any = 0;
 897
 898        r = -EINVAL;
 899        if (log->slot >= KVM_MEMORY_SLOTS)
 900                goto out;
 901
 902        memslot = id_to_memslot(kvm->memslots, log->slot);
 903        r = -ENOENT;
 904        if (!memslot->dirty_bitmap)
 905                goto out;
 906
 907        n = kvm_dirty_bitmap_bytes(memslot);
 908
 909        for (i = 0; !any && i < n/sizeof(long); ++i)
 910                any = memslot->dirty_bitmap[i];
 911
 912        r = -EFAULT;
 913        if (copy_to_user(log->dirty_bitmap, memslot->dirty_bitmap, n))
 914                goto out;
 915
 916        if (any)
 917                *is_dirty = 1;
 918
 919        r = 0;
 920out:
 921        return r;
 922}
 923
 924bool kvm_largepages_enabled(void)
 925{
 926        return largepages_enabled;
 927}
 928
 929void kvm_disable_largepages(void)
 930{
 931        largepages_enabled = false;
 932}
 933EXPORT_SYMBOL_GPL(kvm_disable_largepages);
 934
 935struct kvm_memory_slot *gfn_to_memslot(struct kvm *kvm, gfn_t gfn)
 936{
 937        return __gfn_to_memslot(kvm_memslots(kvm), gfn);
 938}
 939EXPORT_SYMBOL_GPL(gfn_to_memslot);
 940
 941int kvm_is_visible_gfn(struct kvm *kvm, gfn_t gfn)
 942{
 943        struct kvm_memory_slot *memslot = gfn_to_memslot(kvm, gfn);
 944
 945        if (!memslot || memslot->id >= KVM_MEMORY_SLOTS ||
 946              memslot->flags & KVM_MEMSLOT_INVALID)
 947                return 0;
 948
 949        return 1;
 950}
 951EXPORT_SYMBOL_GPL(kvm_is_visible_gfn);
 952
 953unsigned long kvm_host_page_size(struct kvm *kvm, gfn_t gfn)
 954{
 955        struct vm_area_struct *vma;
 956        unsigned long addr, size;
 957
 958        size = PAGE_SIZE;
 959
 960        addr = gfn_to_hva(kvm, gfn);
 961        if (kvm_is_error_hva(addr))
 962                return PAGE_SIZE;
 963
 964        down_read(&current->mm->mmap_sem);
 965        vma = find_vma(current->mm, addr);
 966        if (!vma)
 967                goto out;
 968
 969        size = vma_kernel_pagesize(vma);
 970
 971out:
 972        up_read(&current->mm->mmap_sem);
 973
 974        return size;
 975}
 976
 977static bool memslot_is_readonly(struct kvm_memory_slot *slot)
 978{
 979        return slot->flags & KVM_MEM_READONLY;
 980}
 981
 982static unsigned long __gfn_to_hva_many(struct kvm_memory_slot *slot, gfn_t gfn,
 983                                       gfn_t *nr_pages, bool write)
 984{
 985        if (!slot || slot->flags & KVM_MEMSLOT_INVALID)
 986                return KVM_HVA_ERR_BAD;
 987
 988        if (memslot_is_readonly(slot) && write)
 989                return KVM_HVA_ERR_RO_BAD;
 990
 991        if (nr_pages)
 992                *nr_pages = slot->npages - (gfn - slot->base_gfn);
 993
 994        return __gfn_to_hva_memslot(slot, gfn);
 995}
 996
 997static unsigned long gfn_to_hva_many(struct kvm_memory_slot *slot, gfn_t gfn,
 998                                     gfn_t *nr_pages)
 999{
1000        return __gfn_to_hva_many(slot, gfn, nr_pages, true);
1001}
1002
1003unsigned long gfn_to_hva_memslot(struct kvm_memory_slot *slot,
1004                                 gfn_t gfn)
1005{
1006        return gfn_to_hva_many(slot, gfn, NULL);
1007}
1008EXPORT_SYMBOL_GPL(gfn_to_hva_memslot);
1009
1010unsigned long gfn_to_hva(struct kvm *kvm, gfn_t gfn)
1011{
1012        return gfn_to_hva_many(gfn_to_memslot(kvm, gfn), gfn, NULL);
1013}
1014EXPORT_SYMBOL_GPL(gfn_to_hva);
1015
1016/*
1017 * The hva returned by this function is only allowed to be read.
1018 * It should pair with kvm_read_hva() or kvm_read_hva_atomic().
1019 */
1020static unsigned long gfn_to_hva_read(struct kvm *kvm, gfn_t gfn)
1021{
1022        return __gfn_to_hva_many(gfn_to_memslot(kvm, gfn), gfn, NULL, false);
1023}
1024
1025static int kvm_read_hva(void *data, void __user *hva, int len)
1026{
1027        return __copy_from_user(data, hva, len);
1028}
1029
1030static int kvm_read_hva_atomic(void *data, void __user *hva, int len)
1031{
1032        return __copy_from_user_inatomic(data, hva, len);
1033}
1034
1035int get_user_page_nowait(struct task_struct *tsk, struct mm_struct *mm,
1036        unsigned long start, int write, struct page **page)
1037{
1038        int flags = FOLL_TOUCH | FOLL_NOWAIT | FOLL_HWPOISON | FOLL_GET;
1039
1040        if (write)
1041                flags |= FOLL_WRITE;
1042
1043        return __get_user_pages(tsk, mm, start, 1, flags, page, NULL, NULL);
1044}
1045
1046static inline int check_user_page_hwpoison(unsigned long addr)
1047{
1048        int rc, flags = FOLL_TOUCH | FOLL_HWPOISON | FOLL_WRITE;
1049
1050        rc = __get_user_pages(current, current->mm, addr, 1,
1051                              flags, NULL, NULL, NULL);
1052        return rc == -EHWPOISON;
1053}
1054
1055/*
1056 * The atomic path to get the writable pfn which will be stored in @pfn,
1057 * true indicates success, otherwise false is returned.
1058 */
1059static bool hva_to_pfn_fast(unsigned long addr, bool atomic, bool *async,
1060                            bool write_fault, bool *writable, pfn_t *pfn)
1061{
1062        struct page *page[1];
1063        int npages;
1064
1065        if (!(async || atomic))
1066                return false;
1067
1068        /*
1069         * Fast pin a writable pfn only if it is a write fault request
1070         * or the caller allows to map a writable pfn for a read fault
1071         * request.
1072         */
1073        if (!(write_fault || writable))
1074                return false;
1075
1076        npages = __get_user_pages_fast(addr, 1, 1, page);
1077        if (npages == 1) {
1078                *pfn = page_to_pfn(page[0]);
1079
1080                if (writable)
1081                        *writable = true;
1082                return true;
1083        }
1084
1085        return false;
1086}
1087
1088/*
1089 * The slow path to get the pfn of the specified host virtual address,
1090 * 1 indicates success, -errno is returned if error is detected.
1091 */
1092static int hva_to_pfn_slow(unsigned long addr, bool *async, bool write_fault,
1093                           bool *writable, pfn_t *pfn)
1094{
1095        struct page *page[1];
1096        int npages = 0;
1097
1098        might_sleep();
1099
1100        if (writable)
1101                *writable = write_fault;
1102
1103        if (async) {
1104                down_read(&current->mm->mmap_sem);
1105                npages = get_user_page_nowait(current, current->mm,
1106                                              addr, write_fault, page);
1107                up_read(&current->mm->mmap_sem);
1108        } else
1109                npages = get_user_pages_fast(addr, 1, write_fault,
1110                                             page);
1111        if (npages != 1)
1112                return npages;
1113
1114        /* map read fault as writable if possible */
1115        if (unlikely(!write_fault) && writable) {
1116                struct page *wpage[1];
1117
1118                npages = __get_user_pages_fast(addr, 1, 1, wpage);
1119                if (npages == 1) {
1120                        *writable = true;
1121                        put_page(page[0]);
1122                        page[0] = wpage[0];
1123                }
1124
1125                npages = 1;
1126        }
1127        *pfn = page_to_pfn(page[0]);
1128        return npages;
1129}
1130
1131static bool vma_is_valid(struct vm_area_struct *vma, bool write_fault)
1132{
1133        if (unlikely(!(vma->vm_flags & VM_READ)))
1134                return false;
1135
1136        if (write_fault && (unlikely(!(vma->vm_flags & VM_WRITE))))
1137                return false;
1138
1139        return true;
1140}
1141
1142/*
1143 * Pin guest page in memory and return its pfn.
1144 * @addr: host virtual address which maps memory to the guest
1145 * @atomic: whether this function can sleep
1146 * @async: whether this function need to wait IO complete if the
1147 *         host page is not in the memory
1148 * @write_fault: whether we should get a writable host page
1149 * @writable: whether it allows to map a writable host page for !@write_fault
1150 *
1151 * The function will map a writable host page for these two cases:
1152 * 1): @write_fault = true
1153 * 2): @write_fault = false && @writable, @writable will tell the caller
1154 *     whether the mapping is writable.
1155 */
1156static pfn_t hva_to_pfn(unsigned long addr, bool atomic, bool *async,
1157                        bool write_fault, bool *writable)
1158{
1159        struct vm_area_struct *vma;
1160        pfn_t pfn = 0;
1161        int npages;
1162
1163        /* we can do it either atomically or asynchronously, not both */
1164        BUG_ON(atomic && async);
1165
1166        if (hva_to_pfn_fast(addr, atomic, async, write_fault, writable, &pfn))
1167                return pfn;
1168
1169        if (atomic)
1170                return KVM_PFN_ERR_FAULT;
1171
1172        npages = hva_to_pfn_slow(addr, async, write_fault, writable, &pfn);
1173        if (npages == 1)
1174                return pfn;
1175
1176        down_read(&current->mm->mmap_sem);
1177        if (npages == -EHWPOISON ||
1178              (!async && check_user_page_hwpoison(addr))) {
1179                pfn = KVM_PFN_ERR_HWPOISON;
1180                goto exit;
1181        }
1182
1183        vma = find_vma_intersection(current->mm, addr, addr + 1);
1184
1185        if (vma == NULL)
1186                pfn = KVM_PFN_ERR_FAULT;
1187        else if ((vma->vm_flags & VM_PFNMAP)) {
1188                pfn = ((addr - vma->vm_start) >> PAGE_SHIFT) +
1189                        vma->vm_pgoff;
1190                BUG_ON(!kvm_is_mmio_pfn(pfn));
1191        } else {
1192                if (async && vma_is_valid(vma, write_fault))
1193                        *async = true;
1194                pfn = KVM_PFN_ERR_FAULT;
1195        }
1196exit:
1197        up_read(&current->mm->mmap_sem);
1198        return pfn;
1199}
1200
1201static pfn_t
1202__gfn_to_pfn_memslot(struct kvm_memory_slot *slot, gfn_t gfn, bool atomic,
1203                     bool *async, bool write_fault, bool *writable)
1204{
1205        unsigned long addr = __gfn_to_hva_many(slot, gfn, NULL, write_fault);
1206
1207        if (addr == KVM_HVA_ERR_RO_BAD)
1208                return KVM_PFN_ERR_RO_FAULT;
1209
1210        if (kvm_is_error_hva(addr))
1211                return KVM_PFN_ERR_BAD;
1212
1213        /* Do not map writable pfn in the readonly memslot. */
1214        if (writable && memslot_is_readonly(slot)) {
1215                *writable = false;
1216                writable = NULL;
1217        }
1218
1219        return hva_to_pfn(addr, atomic, async, write_fault,
1220                          writable);
1221}
1222
1223static pfn_t __gfn_to_pfn(struct kvm *kvm, gfn_t gfn, bool atomic, bool *async,
1224                          bool write_fault, bool *writable)
1225{
1226        struct kvm_memory_slot *slot;
1227
1228        if (async)
1229                *async = false;
1230
1231        slot = gfn_to_memslot(kvm, gfn);
1232
1233        return __gfn_to_pfn_memslot(slot, gfn, atomic, async, write_fault,
1234                                    writable);
1235}
1236
1237pfn_t gfn_to_pfn_atomic(struct kvm *kvm, gfn_t gfn)
1238{
1239        return __gfn_to_pfn(kvm, gfn, true, NULL, true, NULL);
1240}
1241EXPORT_SYMBOL_GPL(gfn_to_pfn_atomic);
1242
1243pfn_t gfn_to_pfn_async(struct kvm *kvm, gfn_t gfn, bool *async,
1244                       bool write_fault, bool *writable)
1245{
1246        return __gfn_to_pfn(kvm, gfn, false, async, write_fault, writable);
1247}
1248EXPORT_SYMBOL_GPL(gfn_to_pfn_async);
1249
1250pfn_t gfn_to_pfn(struct kvm *kvm, gfn_t gfn)
1251{
1252        return __gfn_to_pfn(kvm, gfn, false, NULL, true, NULL);
1253}
1254EXPORT_SYMBOL_GPL(gfn_to_pfn);
1255
1256pfn_t gfn_to_pfn_prot(struct kvm *kvm, gfn_t gfn, bool write_fault,
1257                      bool *writable)
1258{
1259        return __gfn_to_pfn(kvm, gfn, false, NULL, write_fault, writable);
1260}
1261EXPORT_SYMBOL_GPL(gfn_to_pfn_prot);
1262
1263pfn_t gfn_to_pfn_memslot(struct kvm_memory_slot *slot, gfn_t gfn)
1264{
1265        return __gfn_to_pfn_memslot(slot, gfn, false, NULL, true, NULL);
1266}
1267
1268pfn_t gfn_to_pfn_memslot_atomic(struct kvm_memory_slot *slot, gfn_t gfn)
1269{
1270        return __gfn_to_pfn_memslot(slot, gfn, true, NULL, true, NULL);
1271}
1272EXPORT_SYMBOL_GPL(gfn_to_pfn_memslot_atomic);
1273
1274int gfn_to_page_many_atomic(struct kvm *kvm, gfn_t gfn, struct page **pages,
1275                                                                  int nr_pages)
1276{
1277        unsigned long addr;
1278        gfn_t entry;
1279
1280        addr = gfn_to_hva_many(gfn_to_memslot(kvm, gfn), gfn, &entry);
1281        if (kvm_is_error_hva(addr))
1282                return -1;
1283
1284        if (entry < nr_pages)
1285                return 0;
1286
1287        return __get_user_pages_fast(addr, nr_pages, 1, pages);
1288}
1289EXPORT_SYMBOL_GPL(gfn_to_page_many_atomic);
1290
1291static struct page *kvm_pfn_to_page(pfn_t pfn)
1292{
1293        if (is_error_pfn(pfn))
1294                return KVM_ERR_PTR_BAD_PAGE;
1295
1296        if (kvm_is_mmio_pfn(pfn)) {
1297                WARN_ON(1);
1298                return KVM_ERR_PTR_BAD_PAGE;
1299        }
1300
1301        return pfn_to_page(pfn);
1302}
1303
1304struct page *gfn_to_page(struct kvm *kvm, gfn_t gfn)
1305{
1306        pfn_t pfn;
1307
1308        pfn = gfn_to_pfn(kvm, gfn);
1309
1310        return kvm_pfn_to_page(pfn);
1311}
1312
1313EXPORT_SYMBOL_GPL(gfn_to_page);
1314
1315void kvm_release_page_clean(struct page *page)
1316{
1317        WARN_ON(is_error_page(page));
1318
1319        kvm_release_pfn_clean(page_to_pfn(page));
1320}
1321EXPORT_SYMBOL_GPL(kvm_release_page_clean);
1322
1323void kvm_release_pfn_clean(pfn_t pfn)
1324{
1325        if (!is_error_pfn(pfn) && !kvm_is_mmio_pfn(pfn))
1326                put_page(pfn_to_page(pfn));
1327}
1328EXPORT_SYMBOL_GPL(kvm_release_pfn_clean);
1329
1330void kvm_release_page_dirty(struct page *page)
1331{
1332        WARN_ON(is_error_page(page));
1333
1334        kvm_release_pfn_dirty(page_to_pfn(page));
1335}
1336EXPORT_SYMBOL_GPL(kvm_release_page_dirty);
1337
1338void kvm_release_pfn_dirty(pfn_t pfn)
1339{
1340        kvm_set_pfn_dirty(pfn);
1341        kvm_release_pfn_clean(pfn);
1342}
1343EXPORT_SYMBOL_GPL(kvm_release_pfn_dirty);
1344
1345void kvm_set_page_dirty(struct page *page)
1346{
1347        kvm_set_pfn_dirty(page_to_pfn(page));
1348}
1349EXPORT_SYMBOL_GPL(kvm_set_page_dirty);
1350
1351void kvm_set_pfn_dirty(pfn_t pfn)
1352{
1353        if (!kvm_is_mmio_pfn(pfn)) {
1354                struct page *page = pfn_to_page(pfn);
1355                if (!PageReserved(page))
1356                        SetPageDirty(page);
1357        }
1358}
1359EXPORT_SYMBOL_GPL(kvm_set_pfn_dirty);
1360
1361void kvm_set_pfn_accessed(pfn_t pfn)
1362{
1363        if (!kvm_is_mmio_pfn(pfn))
1364                mark_page_accessed(pfn_to_page(pfn));
1365}
1366EXPORT_SYMBOL_GPL(kvm_set_pfn_accessed);
1367
1368void kvm_get_pfn(pfn_t pfn)
1369{
1370        if (!kvm_is_mmio_pfn(pfn))
1371                get_page(pfn_to_page(pfn));
1372}
1373EXPORT_SYMBOL_GPL(kvm_get_pfn);
1374
1375static int next_segment(unsigned long len, int offset)
1376{
1377        if (len > PAGE_SIZE - offset)
1378                return PAGE_SIZE - offset;
1379        else
1380                return len;
1381}
1382
1383int kvm_read_guest_page(struct kvm *kvm, gfn_t gfn, void *data, int offset,
1384                        int len)
1385{
1386        int r;
1387        unsigned long addr;
1388
1389        addr = gfn_to_hva_read(kvm, gfn);
1390        if (kvm_is_error_hva(addr))
1391                return -EFAULT;
1392        r = kvm_read_hva(data, (void __user *)addr + offset, len);
1393        if (r)
1394                return -EFAULT;
1395        return 0;
1396}
1397EXPORT_SYMBOL_GPL(kvm_read_guest_page);
1398
1399int kvm_read_guest(struct kvm *kvm, gpa_t gpa, void *data, unsigned long len)
1400{
1401        gfn_t gfn = gpa >> PAGE_SHIFT;
1402        int seg;
1403        int offset = offset_in_page(gpa);
1404        int ret;
1405
1406        while ((seg = next_segment(len, offset)) != 0) {
1407                ret = kvm_read_guest_page(kvm, gfn, data, offset, seg);
1408                if (ret < 0)
1409                        return ret;
1410                offset = 0;
1411                len -= seg;
1412                data += seg;
1413                ++gfn;
1414        }
1415        return 0;
1416}
1417EXPORT_SYMBOL_GPL(kvm_read_guest);
1418
1419int kvm_read_guest_atomic(struct kvm *kvm, gpa_t gpa, void *data,
1420                          unsigned long len)
1421{
1422        int r;
1423        unsigned long addr;
1424        gfn_t gfn = gpa >> PAGE_SHIFT;
1425        int offset = offset_in_page(gpa);
1426
1427        addr = gfn_to_hva_read(kvm, gfn);
1428        if (kvm_is_error_hva(addr))
1429                return -EFAULT;
1430        pagefault_disable();
1431        r = kvm_read_hva_atomic(data, (void __user *)addr + offset, len);
1432        pagefault_enable();
1433        if (r)
1434                return -EFAULT;
1435        return 0;
1436}
1437EXPORT_SYMBOL(kvm_read_guest_atomic);
1438
1439int kvm_write_guest_page(struct kvm *kvm, gfn_t gfn, const void *data,
1440                         int offset, int len)
1441{
1442        int r;
1443        unsigned long addr;
1444
1445        addr = gfn_to_hva(kvm, gfn);
1446        if (kvm_is_error_hva(addr))
1447                return -EFAULT;
1448        r = __copy_to_user((void __user *)addr + offset, data, len);
1449        if (r)
1450                return -EFAULT;
1451        mark_page_dirty(kvm, gfn);
1452        return 0;
1453}
1454EXPORT_SYMBOL_GPL(kvm_write_guest_page);
1455
1456int kvm_write_guest(struct kvm *kvm, gpa_t gpa, const void *data,
1457                    unsigned long len)
1458{
1459        gfn_t gfn = gpa >> PAGE_SHIFT;
1460        int seg;
1461        int offset = offset_in_page(gpa);
1462        int ret;
1463
1464        while ((seg = next_segment(len, offset)) != 0) {
1465                ret = kvm_write_guest_page(kvm, gfn, data, offset, seg);
1466                if (ret < 0)
1467                        return ret;
1468                offset = 0;
1469                len -= seg;
1470                data += seg;
1471                ++gfn;
1472        }
1473        return 0;
1474}
1475
1476int kvm_gfn_to_hva_cache_init(struct kvm *kvm, struct gfn_to_hva_cache *ghc,
1477                              gpa_t gpa)
1478{
1479        struct kvm_memslots *slots = kvm_memslots(kvm);
1480        int offset = offset_in_page(gpa);
1481        gfn_t gfn = gpa >> PAGE_SHIFT;
1482
1483        ghc->gpa = gpa;
1484        ghc->generation = slots->generation;
1485        ghc->memslot = gfn_to_memslot(kvm, gfn);
1486        ghc->hva = gfn_to_hva_many(ghc->memslot, gfn, NULL);
1487        if (!kvm_is_error_hva(ghc->hva))
1488                ghc->hva += offset;
1489        else
1490                return -EFAULT;
1491
1492        return 0;
1493}
1494EXPORT_SYMBOL_GPL(kvm_gfn_to_hva_cache_init);
1495
1496int kvm_write_guest_cached(struct kvm *kvm, struct gfn_to_hva_cache *ghc,
1497                           void *data, unsigned long len)
1498{
1499        struct kvm_memslots *slots = kvm_memslots(kvm);
1500        int r;
1501
1502        if (slots->generation != ghc->generation)
1503                kvm_gfn_to_hva_cache_init(kvm, ghc, ghc->gpa);
1504
1505        if (kvm_is_error_hva(ghc->hva))
1506                return -EFAULT;
1507
1508        r = __copy_to_user((void __user *)ghc->hva, data, len);
1509        if (r)
1510                return -EFAULT;
1511        mark_page_dirty_in_slot(kvm, ghc->memslot, ghc->gpa >> PAGE_SHIFT);
1512
1513        return 0;
1514}
1515EXPORT_SYMBOL_GPL(kvm_write_guest_cached);
1516
1517int kvm_read_guest_cached(struct kvm *kvm, struct gfn_to_hva_cache *ghc,
1518                           void *data, unsigned long len)
1519{
1520        struct kvm_memslots *slots = kvm_memslots(kvm);
1521        int r;
1522
1523        if (slots->generation != ghc->generation)
1524                kvm_gfn_to_hva_cache_init(kvm, ghc, ghc->gpa);
1525
1526        if (kvm_is_error_hva(ghc->hva))
1527                return -EFAULT;
1528
1529        r = __copy_from_user(data, (void __user *)ghc->hva, len);
1530        if (r)
1531                return -EFAULT;
1532
1533        return 0;
1534}
1535EXPORT_SYMBOL_GPL(kvm_read_guest_cached);
1536
1537int kvm_clear_guest_page(struct kvm *kvm, gfn_t gfn, int offset, int len)
1538{
1539        return kvm_write_guest_page(kvm, gfn, (const void *) empty_zero_page,
1540                                    offset, len);
1541}
1542EXPORT_SYMBOL_GPL(kvm_clear_guest_page);
1543
1544int kvm_clear_guest(struct kvm *kvm, gpa_t gpa, unsigned long len)
1545{
1546        gfn_t gfn = gpa >> PAGE_SHIFT;
1547        int seg;
1548        int offset = offset_in_page(gpa);
1549        int ret;
1550
1551        while ((seg = next_segment(len, offset)) != 0) {
1552                ret = kvm_clear_guest_page(kvm, gfn, offset, seg);
1553                if (ret < 0)
1554                        return ret;
1555                offset = 0;
1556                len -= seg;
1557                ++gfn;
1558        }
1559        return 0;
1560}
1561EXPORT_SYMBOL_GPL(kvm_clear_guest);
1562
1563void mark_page_dirty_in_slot(struct kvm *kvm, struct kvm_memory_slot *memslot,
1564                             gfn_t gfn)
1565{
1566        if (memslot && memslot->dirty_bitmap) {
1567                unsigned long rel_gfn = gfn - memslot->base_gfn;
1568
1569                set_bit_le(rel_gfn, memslot->dirty_bitmap);
1570        }
1571}
1572
1573void mark_page_dirty(struct kvm *kvm, gfn_t gfn)
1574{
1575        struct kvm_memory_slot *memslot;
1576
1577        memslot = gfn_to_memslot(kvm, gfn);
1578        mark_page_dirty_in_slot(kvm, memslot, gfn);
1579}
1580
1581/*
1582 * The vCPU has executed a HLT instruction with in-kernel mode enabled.
1583 */
1584void kvm_vcpu_block(struct kvm_vcpu *vcpu)
1585{
1586        DEFINE_WAIT(wait);
1587
1588        for (;;) {
1589                prepare_to_wait(&vcpu->wq, &wait, TASK_INTERRUPTIBLE);
1590
1591                if (kvm_arch_vcpu_runnable(vcpu)) {
1592                        kvm_make_request(KVM_REQ_UNHALT, vcpu);
1593                        break;
1594                }
1595                if (kvm_cpu_has_pending_timer(vcpu))
1596                        break;
1597                if (signal_pending(current))
1598                        break;
1599
1600                schedule();
1601        }
1602
1603        finish_wait(&vcpu->wq, &wait);
1604}
1605
1606#ifndef CONFIG_S390
1607/*
1608 * Kick a sleeping VCPU, or a guest VCPU in guest mode, into host kernel mode.
1609 */
1610void kvm_vcpu_kick(struct kvm_vcpu *vcpu)
1611{
1612        int me;
1613        int cpu = vcpu->cpu;
1614        wait_queue_head_t *wqp;
1615
1616        wqp = kvm_arch_vcpu_wq(vcpu);
1617        if (waitqueue_active(wqp)) {
1618                wake_up_interruptible(wqp);
1619                ++vcpu->stat.halt_wakeup;
1620        }
1621
1622        me = get_cpu();
1623        if (cpu != me && (unsigned)cpu < nr_cpu_ids && cpu_online(cpu))
1624                if (kvm_arch_vcpu_should_kick(vcpu))
1625                        smp_send_reschedule(cpu);
1626        put_cpu();
1627}
1628#endif /* !CONFIG_S390 */
1629
1630void kvm_resched(struct kvm_vcpu *vcpu)
1631{
1632        if (!need_resched())
1633                return;
1634        cond_resched();
1635}
1636EXPORT_SYMBOL_GPL(kvm_resched);
1637
1638bool kvm_vcpu_yield_to(struct kvm_vcpu *target)
1639{
1640        struct pid *pid;
1641        struct task_struct *task = NULL;
1642
1643        rcu_read_lock();
1644        pid = rcu_dereference(target->pid);
1645        if (pid)
1646                task = get_pid_task(target->pid, PIDTYPE_PID);
1647        rcu_read_unlock();
1648        if (!task)
1649                return false;
1650        if (task->flags & PF_VCPU) {
1651                put_task_struct(task);
1652                return false;
1653        }
1654        if (yield_to(task, 1)) {
1655                put_task_struct(task);
1656                return true;
1657        }
1658        put_task_struct(task);
1659        return false;
1660}
1661EXPORT_SYMBOL_GPL(kvm_vcpu_yield_to);
1662
1663#ifdef CONFIG_HAVE_KVM_CPU_RELAX_INTERCEPT
1664/*
1665 * Helper that checks whether a VCPU is eligible for directed yield.
1666 * Most eligible candidate to yield is decided by following heuristics:
1667 *
1668 *  (a) VCPU which has not done pl-exit or cpu relax intercepted recently
1669 *  (preempted lock holder), indicated by @in_spin_loop.
1670 *  Set at the beiginning and cleared at the end of interception/PLE handler.
1671 *
1672 *  (b) VCPU which has done pl-exit/ cpu relax intercepted but did not get
1673 *  chance last time (mostly it has become eligible now since we have probably
1674 *  yielded to lockholder in last iteration. This is done by toggling
1675 *  @dy_eligible each time a VCPU checked for eligibility.)
1676 *
1677 *  Yielding to a recently pl-exited/cpu relax intercepted VCPU before yielding
1678 *  to preempted lock-holder could result in wrong VCPU selection and CPU
1679 *  burning. Giving priority for a potential lock-holder increases lock
1680 *  progress.
1681 *
1682 *  Since algorithm is based on heuristics, accessing another VCPU data without
1683 *  locking does not harm. It may result in trying to yield to  same VCPU, fail
1684 *  and continue with next VCPU and so on.
1685 */
1686bool kvm_vcpu_eligible_for_directed_yield(struct kvm_vcpu *vcpu)
1687{
1688        bool eligible;
1689
1690        eligible = !vcpu->spin_loop.in_spin_loop ||
1691                        (vcpu->spin_loop.in_spin_loop &&
1692                         vcpu->spin_loop.dy_eligible);
1693
1694        if (vcpu->spin_loop.in_spin_loop)
1695                kvm_vcpu_set_dy_eligible(vcpu, !vcpu->spin_loop.dy_eligible);
1696
1697        return eligible;
1698}
1699#endif
1700void kvm_vcpu_on_spin(struct kvm_vcpu *me)
1701{
1702        struct kvm *kvm = me->kvm;
1703        struct kvm_vcpu *vcpu;
1704        int last_boosted_vcpu = me->kvm->last_boosted_vcpu;
1705        int yielded = 0;
1706        int pass;
1707        int i;
1708
1709        kvm_vcpu_set_in_spin_loop(me, true);
1710        /*
1711         * We boost the priority of a VCPU that is runnable but not
1712         * currently running, because it got preempted by something
1713         * else and called schedule in __vcpu_run.  Hopefully that
1714         * VCPU is holding the lock that we need and will release it.
1715         * We approximate round-robin by starting at the last boosted VCPU.
1716         */
1717        for (pass = 0; pass < 2 && !yielded; pass++) {
1718                kvm_for_each_vcpu(i, vcpu, kvm) {
1719                        if (!pass && i <= last_boosted_vcpu) {
1720                                i = last_boosted_vcpu;
1721                                continue;
1722                        } else if (pass && i > last_boosted_vcpu)
1723                                break;
1724                        if (vcpu == me)
1725                                continue;
1726                        if (waitqueue_active(&vcpu->wq))
1727                                continue;
1728                        if (!kvm_vcpu_eligible_for_directed_yield(vcpu))
1729                                continue;
1730                        if (kvm_vcpu_yield_to(vcpu)) {
1731                                kvm->last_boosted_vcpu = i;
1732                                yielded = 1;
1733                                break;
1734                        }
1735                }
1736        }
1737        kvm_vcpu_set_in_spin_loop(me, false);
1738
1739        /* Ensure vcpu is not eligible during next spinloop */
1740        kvm_vcpu_set_dy_eligible(me, false);
1741}
1742EXPORT_SYMBOL_GPL(kvm_vcpu_on_spin);
1743
1744static int kvm_vcpu_fault(struct vm_area_struct *vma, struct vm_fault *vmf)
1745{
1746        struct kvm_vcpu *vcpu = vma->vm_file->private_data;
1747        struct page *page;
1748
1749        if (vmf->pgoff == 0)
1750                page = virt_to_page(vcpu->run);
1751#ifdef CONFIG_X86
1752        else if (vmf->pgoff == KVM_PIO_PAGE_OFFSET)
1753                page = virt_to_page(vcpu->arch.pio_data);
1754#endif
1755#ifdef KVM_COALESCED_MMIO_PAGE_OFFSET
1756        else if (vmf->pgoff == KVM_COALESCED_MMIO_PAGE_OFFSET)
1757                page = virt_to_page(vcpu->kvm->coalesced_mmio_ring);
1758#endif
1759        else
1760                return kvm_arch_vcpu_fault(vcpu, vmf);
1761        get_page(page);
1762        vmf->page = page;
1763        return 0;
1764}
1765
1766static const struct vm_operations_struct kvm_vcpu_vm_ops = {
1767        .fault = kvm_vcpu_fault,
1768};
1769
1770static int kvm_vcpu_mmap(struct file *file, struct vm_area_struct *vma)
1771{
1772        vma->vm_ops = &kvm_vcpu_vm_ops;
1773        return 0;
1774}
1775
1776static int kvm_vcpu_release(struct inode *inode, struct file *filp)
1777{
1778        struct kvm_vcpu *vcpu = filp->private_data;
1779
1780        kvm_put_kvm(vcpu->kvm);
1781        return 0;
1782}
1783
1784static struct file_operations kvm_vcpu_fops = {
1785        .release        = kvm_vcpu_release,
1786        .unlocked_ioctl = kvm_vcpu_ioctl,
1787#ifdef CONFIG_COMPAT
1788        .compat_ioctl   = kvm_vcpu_compat_ioctl,
1789#endif
1790        .mmap           = kvm_vcpu_mmap,
1791        .llseek         = noop_llseek,
1792};
1793
1794/*
1795 * Allocates an inode for the vcpu.
1796 */
1797static int create_vcpu_fd(struct kvm_vcpu *vcpu)
1798{
1799        return anon_inode_getfd("kvm-vcpu", &kvm_vcpu_fops, vcpu, O_RDWR);
1800}
1801
1802/*
1803 * Creates some virtual cpus.  Good luck creating more than one.
1804 */
1805static int kvm_vm_ioctl_create_vcpu(struct kvm *kvm, u32 id)
1806{
1807        int r;
1808        struct kvm_vcpu *vcpu, *v;
1809
1810        vcpu = kvm_arch_vcpu_create(kvm, id);
1811        if (IS_ERR(vcpu))
1812                return PTR_ERR(vcpu);
1813
1814        preempt_notifier_init(&vcpu->preempt_notifier, &kvm_preempt_ops);
1815
1816        r = kvm_arch_vcpu_setup(vcpu);
1817        if (r)
1818                goto vcpu_destroy;
1819
1820        mutex_lock(&kvm->lock);
1821        if (!kvm_vcpu_compatible(vcpu)) {
1822                r = -EINVAL;
1823                goto unlock_vcpu_destroy;
1824        }
1825        if (atomic_read(&kvm->online_vcpus) == KVM_MAX_VCPUS) {
1826                r = -EINVAL;
1827                goto unlock_vcpu_destroy;
1828        }
1829
1830        kvm_for_each_vcpu(r, v, kvm)
1831                if (v->vcpu_id == id) {
1832                        r = -EEXIST;
1833                        goto unlock_vcpu_destroy;
1834                }
1835
1836        BUG_ON(kvm->vcpus[atomic_read(&kvm->online_vcpus)]);
1837
1838        /* Now it's all set up, let userspace reach it */
1839        kvm_get_kvm(kvm);
1840        r = create_vcpu_fd(vcpu);
1841        if (r < 0) {
1842                kvm_put_kvm(kvm);
1843                goto unlock_vcpu_destroy;
1844        }
1845
1846        kvm->vcpus[atomic_read(&kvm->online_vcpus)] = vcpu;
1847        smp_wmb();
1848        atomic_inc(&kvm->online_vcpus);
1849
1850        mutex_unlock(&kvm->lock);
1851        return r;
1852
1853unlock_vcpu_destroy:
1854        mutex_unlock(&kvm->lock);
1855vcpu_destroy:
1856        kvm_arch_vcpu_destroy(vcpu);
1857        return r;
1858}
1859
1860static int kvm_vcpu_ioctl_set_sigmask(struct kvm_vcpu *vcpu, sigset_t *sigset)
1861{
1862        if (sigset) {
1863                sigdelsetmask(sigset, sigmask(SIGKILL)|sigmask(SIGSTOP));
1864                vcpu->sigset_active = 1;
1865                vcpu->sigset = *sigset;
1866        } else
1867                vcpu->sigset_active = 0;
1868        return 0;
1869}
1870
1871static long kvm_vcpu_ioctl(struct file *filp,
1872                           unsigned int ioctl, unsigned long arg)
1873{
1874        struct kvm_vcpu *vcpu = filp->private_data;
1875        void __user *argp = (void __user *)arg;
1876        int r;
1877        struct kvm_fpu *fpu = NULL;
1878        struct kvm_sregs *kvm_sregs = NULL;
1879
1880        if (vcpu->kvm->mm != current->mm)
1881                return -EIO;
1882
1883#if defined(CONFIG_S390) || defined(CONFIG_PPC)
1884        /*
1885         * Special cases: vcpu ioctls that are asynchronous to vcpu execution,
1886         * so vcpu_load() would break it.
1887         */
1888        if (ioctl == KVM_S390_INTERRUPT || ioctl == KVM_INTERRUPT)
1889                return kvm_arch_vcpu_ioctl(filp, ioctl, arg);
1890#endif
1891
1892
1893        r = vcpu_load(vcpu);
1894        if (r)
1895                return r;
1896        switch (ioctl) {
1897        case KVM_RUN:
1898                r = -EINVAL;
1899                if (arg)
1900                        goto out;
1901                r = kvm_arch_vcpu_ioctl_run(vcpu, vcpu->run);
1902                trace_kvm_userspace_exit(vcpu->run->exit_reason, r);
1903                break;
1904        case KVM_GET_REGS: {
1905                struct kvm_regs *kvm_regs;
1906
1907                r = -ENOMEM;
1908                kvm_regs = kzalloc(sizeof(struct kvm_regs), GFP_KERNEL);
1909                if (!kvm_regs)
1910                        goto out;
1911                r = kvm_arch_vcpu_ioctl_get_regs(vcpu, kvm_regs);
1912                if (r)
1913                        goto out_free1;
1914                r = -EFAULT;
1915                if (copy_to_user(argp, kvm_regs, sizeof(struct kvm_regs)))
1916                        goto out_free1;
1917                r = 0;
1918out_free1:
1919                kfree(kvm_regs);
1920                break;
1921        }
1922        case KVM_SET_REGS: {
1923                struct kvm_regs *kvm_regs;
1924
1925                r = -ENOMEM;
1926                kvm_regs = memdup_user(argp, sizeof(*kvm_regs));
1927                if (IS_ERR(kvm_regs)) {
1928                        r = PTR_ERR(kvm_regs);
1929                        goto out;
1930                }
1931                r = kvm_arch_vcpu_ioctl_set_regs(vcpu, kvm_regs);
1932                if (r)
1933                        goto out_free2;
1934                r = 0;
1935out_free2:
1936                kfree(kvm_regs);
1937                break;
1938        }
1939        case KVM_GET_SREGS: {
1940                kvm_sregs = kzalloc(sizeof(struct kvm_sregs), GFP_KERNEL);
1941                r = -ENOMEM;
1942                if (!kvm_sregs)
1943                        goto out;
1944                r = kvm_arch_vcpu_ioctl_get_sregs(vcpu, kvm_sregs);
1945                if (r)
1946                        goto out;
1947                r = -EFAULT;
1948                if (copy_to_user(argp, kvm_sregs, sizeof(struct kvm_sregs)))
1949                        goto out;
1950                r = 0;
1951                break;
1952        }
1953        case KVM_SET_SREGS: {
1954                kvm_sregs = memdup_user(argp, sizeof(*kvm_sregs));
1955                if (IS_ERR(kvm_sregs)) {
1956                        r = PTR_ERR(kvm_sregs);
1957                        goto out;
1958                }
1959                r = kvm_arch_vcpu_ioctl_set_sregs(vcpu, kvm_sregs);
1960                if (r)
1961                        goto out;
1962                r = 0;
1963                break;
1964        }
1965        case KVM_GET_MP_STATE: {
1966                struct kvm_mp_state mp_state;
1967
1968                r = kvm_arch_vcpu_ioctl_get_mpstate(vcpu, &mp_state);
1969                if (r)
1970                        goto out;
1971                r = -EFAULT;
1972                if (copy_to_user(argp, &mp_state, sizeof mp_state))
1973                        goto out;
1974                r = 0;
1975                break;
1976        }
1977        case KVM_SET_MP_STATE: {
1978                struct kvm_mp_state mp_state;
1979
1980                r = -EFAULT;
1981                if (copy_from_user(&mp_state, argp, sizeof mp_state))
1982                        goto out;
1983                r = kvm_arch_vcpu_ioctl_set_mpstate(vcpu, &mp_state);
1984                if (r)
1985                        goto out;
1986                r = 0;
1987                break;
1988        }
1989        case KVM_TRANSLATE: {
1990                struct kvm_translation tr;
1991
1992                r = -EFAULT;
1993                if (copy_from_user(&tr, argp, sizeof tr))
1994                        goto out;
1995                r = kvm_arch_vcpu_ioctl_translate(vcpu, &tr);
1996                if (r)
1997                        goto out;
1998                r = -EFAULT;
1999                if (copy_to_user(argp, &tr, sizeof tr))
2000                        goto out;
2001                r = 0;
2002                break;
2003        }
2004        case KVM_SET_GUEST_DEBUG: {
2005                struct kvm_guest_debug dbg;
2006
2007                r = -EFAULT;
2008                if (copy_from_user(&dbg, argp, sizeof dbg))
2009                        goto out;
2010                r = kvm_arch_vcpu_ioctl_set_guest_debug(vcpu, &dbg);
2011                if (r)
2012                        goto out;
2013                r = 0;
2014                break;
2015        }
2016        case KVM_SET_SIGNAL_MASK: {
2017                struct kvm_signal_mask __user *sigmask_arg = argp;
2018                struct kvm_signal_mask kvm_sigmask;
2019                sigset_t sigset, *p;
2020
2021                p = NULL;
2022                if (argp) {
2023                        r = -EFAULT;
2024                        if (copy_from_user(&kvm_sigmask, argp,
2025                                           sizeof kvm_sigmask))
2026                                goto out;
2027                        r = -EINVAL;
2028                        if (kvm_sigmask.len != sizeof sigset)
2029                                goto out;
2030                        r = -EFAULT;
2031                        if (copy_from_user(&sigset, sigmask_arg->sigset,
2032                                           sizeof sigset))
2033                                goto out;
2034                        p = &sigset;
2035                }
2036                r = kvm_vcpu_ioctl_set_sigmask(vcpu, p);
2037                break;
2038        }
2039        case KVM_GET_FPU: {
2040                fpu = kzalloc(sizeof(struct kvm_fpu), GFP_KERNEL);
2041                r = -ENOMEM;
2042                if (!fpu)
2043                        goto out;
2044                r = kvm_arch_vcpu_ioctl_get_fpu(vcpu, fpu);
2045                if (r)
2046                        goto out;
2047                r = -EFAULT;
2048                if (copy_to_user(argp, fpu, sizeof(struct kvm_fpu)))
2049                        goto out;
2050                r = 0;
2051                break;
2052        }
2053        case KVM_SET_FPU: {
2054                fpu = memdup_user(argp, sizeof(*fpu));
2055                if (IS_ERR(fpu)) {
2056                        r = PTR_ERR(fpu);
2057                        goto out;
2058                }
2059                r = kvm_arch_vcpu_ioctl_set_fpu(vcpu, fpu);
2060                if (r)
2061                        goto out;
2062                r = 0;
2063                break;
2064        }
2065        default:
2066                r = kvm_arch_vcpu_ioctl(filp, ioctl, arg);
2067        }
2068out:
2069        vcpu_put(vcpu);
2070        kfree(fpu);
2071        kfree(kvm_sregs);
2072        return r;
2073}
2074
2075#ifdef CONFIG_COMPAT
2076static long kvm_vcpu_compat_ioctl(struct file *filp,
2077                                  unsigned int ioctl, unsigned long arg)
2078{
2079        struct kvm_vcpu *vcpu = filp->private_data;
2080        void __user *argp = compat_ptr(arg);
2081        int r;
2082
2083        if (vcpu->kvm->mm != current->mm)
2084                return -EIO;
2085
2086        switch (ioctl) {
2087        case KVM_SET_SIGNAL_MASK: {
2088                struct kvm_signal_mask __user *sigmask_arg = argp;
2089                struct kvm_signal_mask kvm_sigmask;
2090                compat_sigset_t csigset;
2091                sigset_t sigset;
2092
2093                if (argp) {
2094                        r = -EFAULT;
2095                        if (copy_from_user(&kvm_sigmask, argp,
2096                                           sizeof kvm_sigmask))
2097                                goto out;
2098                        r = -EINVAL;
2099                        if (kvm_sigmask.len != sizeof csigset)
2100                                goto out;
2101                        r = -EFAULT;
2102                        if (copy_from_user(&csigset, sigmask_arg->sigset,
2103                                           sizeof csigset))
2104                                goto out;
2105                        sigset_from_compat(&sigset, &csigset);
2106                        r = kvm_vcpu_ioctl_set_sigmask(vcpu, &sigset);
2107                } else
2108                        r = kvm_vcpu_ioctl_set_sigmask(vcpu, NULL);
2109                break;
2110        }
2111        default:
2112                r = kvm_vcpu_ioctl(filp, ioctl, arg);
2113        }
2114
2115out:
2116        return r;
2117}
2118#endif
2119
2120static long kvm_vm_ioctl(struct file *filp,
2121                           unsigned int ioctl, unsigned long arg)
2122{
2123        struct kvm *kvm = filp->private_data;
2124        void __user *argp = (void __user *)arg;
2125        int r;
2126
2127        if (kvm->mm != current->mm)
2128                return -EIO;
2129        switch (ioctl) {
2130        case KVM_CREATE_VCPU:
2131                r = kvm_vm_ioctl_create_vcpu(kvm, arg);
2132                if (r < 0)
2133                        goto out;
2134                break;
2135        case KVM_SET_USER_MEMORY_REGION: {
2136                struct kvm_userspace_memory_region kvm_userspace_mem;
2137
2138                r = -EFAULT;
2139                if (copy_from_user(&kvm_userspace_mem, argp,
2140                                                sizeof kvm_userspace_mem))
2141                        goto out;
2142
2143                r = kvm_vm_ioctl_set_memory_region(kvm, &kvm_userspace_mem, 1);
2144                if (r)
2145                        goto out;
2146                break;
2147        }
2148        case KVM_GET_DIRTY_LOG: {
2149                struct kvm_dirty_log log;
2150
2151                r = -EFAULT;
2152                if (copy_from_user(&log, argp, sizeof log))
2153                        goto out;
2154                r = kvm_vm_ioctl_get_dirty_log(kvm, &log);
2155                if (r)
2156                        goto out;
2157                break;
2158        }
2159#ifdef KVM_COALESCED_MMIO_PAGE_OFFSET
2160        case KVM_REGISTER_COALESCED_MMIO: {
2161                struct kvm_coalesced_mmio_zone zone;
2162                r = -EFAULT;
2163                if (copy_from_user(&zone, argp, sizeof zone))
2164                        goto out;
2165                r = kvm_vm_ioctl_register_coalesced_mmio(kvm, &zone);
2166                if (r)
2167                        goto out;
2168                r = 0;
2169                break;
2170        }
2171        case KVM_UNREGISTER_COALESCED_MMIO: {
2172                struct kvm_coalesced_mmio_zone zone;
2173                r = -EFAULT;
2174                if (copy_from_user(&zone, argp, sizeof zone))
2175                        goto out;
2176                r = kvm_vm_ioctl_unregister_coalesced_mmio(kvm, &zone);
2177                if (r)
2178                        goto out;
2179                r = 0;
2180                break;
2181        }
2182#endif
2183        case KVM_IRQFD: {
2184                struct kvm_irqfd data;
2185
2186                r = -EFAULT;
2187                if (copy_from_user(&data, argp, sizeof data))
2188                        goto out;
2189                r = kvm_irqfd(kvm, &data);
2190                break;
2191        }
2192        case KVM_IOEVENTFD: {
2193                struct kvm_ioeventfd data;
2194
2195                r = -EFAULT;
2196                if (copy_from_user(&data, argp, sizeof data))
2197                        goto out;
2198                r = kvm_ioeventfd(kvm, &data);
2199                break;
2200        }
2201#ifdef CONFIG_KVM_APIC_ARCHITECTURE
2202        case KVM_SET_BOOT_CPU_ID:
2203                r = 0;
2204                mutex_lock(&kvm->lock);
2205                if (atomic_read(&kvm->online_vcpus) != 0)
2206                        r = -EBUSY;
2207                else
2208                        kvm->bsp_vcpu_id = arg;
2209                mutex_unlock(&kvm->lock);
2210                break;
2211#endif
2212#ifdef CONFIG_HAVE_KVM_MSI
2213        case KVM_SIGNAL_MSI: {
2214                struct kvm_msi msi;
2215
2216                r = -EFAULT;
2217                if (copy_from_user(&msi, argp, sizeof msi))
2218                        goto out;
2219                r = kvm_send_userspace_msi(kvm, &msi);
2220                break;
2221        }
2222#endif
2223#ifdef __KVM_HAVE_IRQ_LINE
2224        case KVM_IRQ_LINE_STATUS:
2225        case KVM_IRQ_LINE: {
2226                struct kvm_irq_level irq_event;
2227
2228                r = -EFAULT;
2229                if (copy_from_user(&irq_event, argp, sizeof irq_event))
2230                        goto out;
2231
2232                r = kvm_vm_ioctl_irq_line(kvm, &irq_event);
2233                if (r)
2234                        goto out;
2235
2236                r = -EFAULT;
2237                if (ioctl == KVM_IRQ_LINE_STATUS) {
2238                        if (copy_to_user(argp, &irq_event, sizeof irq_event))
2239                                goto out;
2240                }
2241
2242                r = 0;
2243                break;
2244        }
2245#endif
2246        default:
2247                r = kvm_arch_vm_ioctl(filp, ioctl, arg);
2248                if (r == -ENOTTY)
2249                        r = kvm_vm_ioctl_assigned_device(kvm, ioctl, arg);
2250        }
2251out:
2252        return r;
2253}
2254
2255#ifdef CONFIG_COMPAT
2256struct compat_kvm_dirty_log {
2257        __u32 slot;
2258        __u32 padding1;
2259        union {
2260                compat_uptr_t dirty_bitmap; /* one bit per page */
2261                __u64 padding2;
2262        };
2263};
2264
2265static long kvm_vm_compat_ioctl(struct file *filp,
2266                           unsigned int ioctl, unsigned long arg)
2267{
2268        struct kvm *kvm = filp->private_data;
2269        int r;
2270
2271        if (kvm->mm != current->mm)
2272                return -EIO;
2273        switch (ioctl) {
2274        case KVM_GET_DIRTY_LOG: {
2275                struct compat_kvm_dirty_log compat_log;
2276                struct kvm_dirty_log log;
2277
2278                r = -EFAULT;
2279                if (copy_from_user(&compat_log, (void __user *)arg,
2280                                   sizeof(compat_log)))
2281                        goto out;
2282                log.slot         = compat_log.slot;
2283                log.padding1     = compat_log.padding1;
2284                log.padding2     = compat_log.padding2;
2285                log.dirty_bitmap = compat_ptr(compat_log.dirty_bitmap);
2286
2287                r = kvm_vm_ioctl_get_dirty_log(kvm, &log);
2288                if (r)
2289                        goto out;
2290                break;
2291        }
2292        default:
2293                r = kvm_vm_ioctl(filp, ioctl, arg);
2294        }
2295
2296out:
2297        return r;
2298}
2299#endif
2300
2301static int kvm_vm_fault(struct vm_area_struct *vma, struct vm_fault *vmf)
2302{
2303        struct page *page[1];
2304        unsigned long addr;
2305        int npages;
2306        gfn_t gfn = vmf->pgoff;
2307        struct kvm *kvm = vma->vm_file->private_data;
2308
2309        addr = gfn_to_hva(kvm, gfn);
2310        if (kvm_is_error_hva(addr))
2311                return VM_FAULT_SIGBUS;
2312
2313        npages = get_user_pages(current, current->mm, addr, 1, 1, 0, page,
2314                                NULL);
2315        if (unlikely(npages != 1))
2316                return VM_FAULT_SIGBUS;
2317
2318        vmf->page = page[0];
2319        return 0;
2320}
2321
2322static const struct vm_operations_struct kvm_vm_vm_ops = {
2323        .fault = kvm_vm_fault,
2324};
2325
2326static int kvm_vm_mmap(struct file *file, struct vm_area_struct *vma)
2327{
2328        vma->vm_ops = &kvm_vm_vm_ops;
2329        return 0;
2330}
2331
2332static struct file_operations kvm_vm_fops = {
2333        .release        = kvm_vm_release,
2334        .unlocked_ioctl = kvm_vm_ioctl,
2335#ifdef CONFIG_COMPAT
2336        .compat_ioctl   = kvm_vm_compat_ioctl,
2337#endif
2338        .mmap           = kvm_vm_mmap,
2339        .llseek         = noop_llseek,
2340};
2341
2342static int kvm_dev_ioctl_create_vm(unsigned long type)
2343{
2344        int r;
2345        struct kvm *kvm;
2346
2347        kvm = kvm_create_vm(type);
2348        if (IS_ERR(kvm))
2349                return PTR_ERR(kvm);
2350#ifdef KVM_COALESCED_MMIO_PAGE_OFFSET
2351        r = kvm_coalesced_mmio_init(kvm);
2352        if (r < 0) {
2353                kvm_put_kvm(kvm);
2354                return r;
2355        }
2356#endif
2357        r = anon_inode_getfd("kvm-vm", &kvm_vm_fops, kvm, O_RDWR);
2358        if (r < 0)
2359                kvm_put_kvm(kvm);
2360
2361        return r;
2362}
2363
2364static long kvm_dev_ioctl_check_extension_generic(long arg)
2365{
2366        switch (arg) {
2367        case KVM_CAP_USER_MEMORY:
2368        case KVM_CAP_DESTROY_MEMORY_REGION_WORKS:
2369        case KVM_CAP_JOIN_MEMORY_REGIONS_WORKS:
2370#ifdef CONFIG_KVM_APIC_ARCHITECTURE
2371        case KVM_CAP_SET_BOOT_CPU_ID:
2372#endif
2373        case KVM_CAP_INTERNAL_ERROR_DATA:
2374#ifdef CONFIG_HAVE_KVM_MSI
2375        case KVM_CAP_SIGNAL_MSI:
2376#endif
2377                return 1;
2378#ifdef KVM_CAP_IRQ_ROUTING
2379        case KVM_CAP_IRQ_ROUTING:
2380                return KVM_MAX_IRQ_ROUTES;
2381#endif
2382        default:
2383                break;
2384        }
2385        return kvm_dev_ioctl_check_extension(arg);
2386}
2387
2388static long kvm_dev_ioctl(struct file *filp,
2389                          unsigned int ioctl, unsigned long arg)
2390{
2391        long r = -EINVAL;
2392
2393        switch (ioctl) {
2394        case KVM_GET_API_VERSION:
2395                r = -EINVAL;
2396                if (arg)
2397                        goto out;
2398                r = KVM_API_VERSION;
2399                break;
2400        case KVM_CREATE_VM:
2401                r = kvm_dev_ioctl_create_vm(arg);
2402                break;
2403        case KVM_CHECK_EXTENSION:
2404                r = kvm_dev_ioctl_check_extension_generic(arg);
2405                break;
2406        case KVM_GET_VCPU_MMAP_SIZE:
2407                r = -EINVAL;
2408                if (arg)
2409                        goto out;
2410                r = PAGE_SIZE;     /* struct kvm_run */
2411#ifdef CONFIG_X86
2412                r += PAGE_SIZE;    /* pio data page */
2413#endif
2414#ifdef KVM_COALESCED_MMIO_PAGE_OFFSET
2415                r += PAGE_SIZE;    /* coalesced mmio ring page */
2416#endif
2417                break;
2418        case KVM_TRACE_ENABLE:
2419        case KVM_TRACE_PAUSE:
2420        case KVM_TRACE_DISABLE:
2421                r = -EOPNOTSUPP;
2422                break;
2423        default:
2424                return kvm_arch_dev_ioctl(filp, ioctl, arg);
2425        }
2426out:
2427        return r;
2428}
2429
2430static struct file_operations kvm_chardev_ops = {
2431        .unlocked_ioctl = kvm_dev_ioctl,
2432        .compat_ioctl   = kvm_dev_ioctl,
2433        .llseek         = noop_llseek,
2434};
2435
2436static struct miscdevice kvm_dev = {
2437        KVM_MINOR,
2438        "kvm",
2439        &kvm_chardev_ops,
2440};
2441
2442static void hardware_enable_nolock(void *junk)
2443{
2444        int cpu = raw_smp_processor_id();
2445        int r;
2446
2447        if (cpumask_test_cpu(cpu, cpus_hardware_enabled))
2448                return;
2449
2450        cpumask_set_cpu(cpu, cpus_hardware_enabled);
2451
2452        r = kvm_arch_hardware_enable(NULL);
2453
2454        if (r) {
2455                cpumask_clear_cpu(cpu, cpus_hardware_enabled);
2456                atomic_inc(&hardware_enable_failed);
2457                printk(KERN_INFO "kvm: enabling virtualization on "
2458                                 "CPU%d failed\n", cpu);
2459        }
2460}
2461
2462static void hardware_enable(void *junk)
2463{
2464        raw_spin_lock(&kvm_lock);
2465        hardware_enable_nolock(junk);
2466        raw_spin_unlock(&kvm_lock);
2467}
2468
2469static void hardware_disable_nolock(void *junk)
2470{
2471        int cpu = raw_smp_processor_id();
2472
2473        if (!cpumask_test_cpu(cpu, cpus_hardware_enabled))
2474                return;
2475        cpumask_clear_cpu(cpu, cpus_hardware_enabled);
2476        kvm_arch_hardware_disable(NULL);
2477}
2478
2479static void hardware_disable(void *junk)
2480{
2481        raw_spin_lock(&kvm_lock);
2482        hardware_disable_nolock(junk);
2483        raw_spin_unlock(&kvm_lock);
2484}
2485
2486static void hardware_disable_all_nolock(void)
2487{
2488        BUG_ON(!kvm_usage_count);
2489
2490        kvm_usage_count--;
2491        if (!kvm_usage_count)
2492                on_each_cpu(hardware_disable_nolock, NULL, 1);
2493}
2494
2495static void hardware_disable_all(void)
2496{
2497        raw_spin_lock(&kvm_lock);
2498        hardware_disable_all_nolock();
2499        raw_spin_unlock(&kvm_lock);
2500}
2501
2502static int hardware_enable_all(void)
2503{
2504        int r = 0;
2505
2506        raw_spin_lock(&kvm_lock);
2507
2508        kvm_usage_count++;
2509        if (kvm_usage_count == 1) {
2510                atomic_set(&hardware_enable_failed, 0);
2511                on_each_cpu(hardware_enable_nolock, NULL, 1);
2512
2513                if (atomic_read(&hardware_enable_failed)) {
2514                        hardware_disable_all_nolock();
2515                        r = -EBUSY;
2516                }
2517        }
2518
2519        raw_spin_unlock(&kvm_lock);
2520
2521        return r;
2522}
2523
2524static int kvm_cpu_hotplug(struct notifier_block *notifier, unsigned long val,
2525                           void *v)
2526{
2527        int cpu = (long)v;
2528
2529        if (!kvm_usage_count)
2530                return NOTIFY_OK;
2531
2532        val &= ~CPU_TASKS_FROZEN;
2533        switch (val) {
2534        case CPU_DYING:
2535                printk(KERN_INFO "kvm: disabling virtualization on CPU%d\n",
2536                       cpu);
2537                hardware_disable(NULL);
2538                break;
2539        case CPU_STARTING:
2540                printk(KERN_INFO "kvm: enabling virtualization on CPU%d\n",
2541                       cpu);
2542                hardware_enable(NULL);
2543                break;
2544        }
2545        return NOTIFY_OK;
2546}
2547
2548
2549asmlinkage void kvm_spurious_fault(void)
2550{
2551        /* Fault while not rebooting.  We want the trace. */
2552        BUG();
2553}
2554EXPORT_SYMBOL_GPL(kvm_spurious_fault);
2555
2556static int kvm_reboot(struct notifier_block *notifier, unsigned long val,
2557                      void *v)
2558{
2559        /*
2560         * Some (well, at least mine) BIOSes hang on reboot if
2561         * in vmx root mode.
2562         *
2563         * And Intel TXT required VMX off for all cpu when system shutdown.
2564         */
2565        printk(KERN_INFO "kvm: exiting hardware virtualization\n");
2566        kvm_rebooting = true;
2567        on_each_cpu(hardware_disable_nolock, NULL, 1);
2568        return NOTIFY_OK;
2569}
2570
2571static struct notifier_block kvm_reboot_notifier = {
2572        .notifier_call = kvm_reboot,
2573        .priority = 0,
2574};
2575
2576static void kvm_io_bus_destroy(struct kvm_io_bus *bus)
2577{
2578        int i;
2579
2580        for (i = 0; i < bus->dev_count; i++) {
2581                struct kvm_io_device *pos = bus->range[i].dev;
2582
2583                kvm_iodevice_destructor(pos);
2584        }
2585        kfree(bus);
2586}
2587
2588int kvm_io_bus_sort_cmp(const void *p1, const void *p2)
2589{
2590        const struct kvm_io_range *r1 = p1;
2591        const struct kvm_io_range *r2 = p2;
2592
2593        if (r1->addr < r2->addr)
2594                return -1;
2595        if (r1->addr + r1->len > r2->addr + r2->len)
2596                return 1;
2597        return 0;
2598}
2599
2600int kvm_io_bus_insert_dev(struct kvm_io_bus *bus, struct kvm_io_device *dev,
2601                          gpa_t addr, int len)
2602{
2603        bus->range[bus->dev_count++] = (struct kvm_io_range) {
2604                .addr = addr,
2605                .len = len,
2606                .dev = dev,
2607        };
2608
2609        sort(bus->range, bus->dev_count, sizeof(struct kvm_io_range),
2610                kvm_io_bus_sort_cmp, NULL);
2611
2612        return 0;
2613}
2614
2615int kvm_io_bus_get_first_dev(struct kvm_io_bus *bus,
2616                             gpa_t addr, int len)
2617{
2618        struct kvm_io_range *range, key;
2619        int off;
2620
2621        key = (struct kvm_io_range) {
2622                .addr = addr,
2623                .len = len,
2624        };
2625
2626        range = bsearch(&key, bus->range, bus->dev_count,
2627                        sizeof(struct kvm_io_range), kvm_io_bus_sort_cmp);
2628        if (range == NULL)
2629                return -ENOENT;
2630
2631        off = range - bus->range;
2632
2633        while (off > 0 && kvm_io_bus_sort_cmp(&key, &bus->range[off-1]) == 0)
2634                off--;
2635
2636        return off;
2637}
2638
2639/* kvm_io_bus_write - called under kvm->slots_lock */
2640int kvm_io_bus_write(struct kvm *kvm, enum kvm_bus bus_idx, gpa_t addr,
2641                     int len, const void *val)
2642{
2643        int idx;
2644        struct kvm_io_bus *bus;
2645        struct kvm_io_range range;
2646
2647        range = (struct kvm_io_range) {
2648                .addr = addr,
2649                .len = len,
2650        };
2651
2652        bus = srcu_dereference(kvm->buses[bus_idx], &kvm->srcu);
2653        idx = kvm_io_bus_get_first_dev(bus, addr, len);
2654        if (idx < 0)
2655                return -EOPNOTSUPP;
2656
2657        while (idx < bus->dev_count &&
2658                kvm_io_bus_sort_cmp(&range, &bus->range[idx]) == 0) {
2659                if (!kvm_iodevice_write(bus->range[idx].dev, addr, len, val))
2660                        return 0;
2661                idx++;
2662        }
2663
2664        return -EOPNOTSUPP;
2665}
2666
2667/* kvm_io_bus_read - called under kvm->slots_lock */
2668int kvm_io_bus_read(struct kvm *kvm, enum kvm_bus bus_idx, gpa_t addr,
2669                    int len, void *val)
2670{
2671        int idx;
2672        struct kvm_io_bus *bus;
2673        struct kvm_io_range range;
2674
2675        range = (struct kvm_io_range) {
2676                .addr = addr,
2677                .len = len,
2678        };
2679
2680        bus = srcu_dereference(kvm->buses[bus_idx], &kvm->srcu);
2681        idx = kvm_io_bus_get_first_dev(bus, addr, len);
2682        if (idx < 0)
2683                return -EOPNOTSUPP;
2684
2685        while (idx < bus->dev_count &&
2686                kvm_io_bus_sort_cmp(&range, &bus->range[idx]) == 0) {
2687                if (!kvm_iodevice_read(bus->range[idx].dev, addr, len, val))
2688                        return 0;
2689                idx++;
2690        }
2691
2692        return -EOPNOTSUPP;
2693}
2694
2695/* Caller must hold slots_lock. */
2696int kvm_io_bus_register_dev(struct kvm *kvm, enum kvm_bus bus_idx, gpa_t addr,
2697                            int len, struct kvm_io_device *dev)
2698{
2699        struct kvm_io_bus *new_bus, *bus;
2700
2701        bus = kvm->buses[bus_idx];
2702        if (bus->dev_count > NR_IOBUS_DEVS - 1)
2703                return -ENOSPC;
2704
2705        new_bus = kzalloc(sizeof(*bus) + ((bus->dev_count + 1) *
2706                          sizeof(struct kvm_io_range)), GFP_KERNEL);
2707        if (!new_bus)
2708                return -ENOMEM;
2709        memcpy(new_bus, bus, sizeof(*bus) + (bus->dev_count *
2710               sizeof(struct kvm_io_range)));
2711        kvm_io_bus_insert_dev(new_bus, dev, addr, len);
2712        rcu_assign_pointer(kvm->buses[bus_idx], new_bus);
2713        synchronize_srcu_expedited(&kvm->srcu);
2714        kfree(bus);
2715
2716        return 0;
2717}
2718
2719/* Caller must hold slots_lock. */
2720int kvm_io_bus_unregister_dev(struct kvm *kvm, enum kvm_bus bus_idx,
2721                              struct kvm_io_device *dev)
2722{
2723        int i, r;
2724        struct kvm_io_bus *new_bus, *bus;
2725
2726        bus = kvm->buses[bus_idx];
2727        r = -ENOENT;
2728        for (i = 0; i < bus->dev_count; i++)
2729                if (bus->range[i].dev == dev) {
2730                        r = 0;
2731                        break;
2732                }
2733
2734        if (r)
2735                return r;
2736
2737        new_bus = kzalloc(sizeof(*bus) + ((bus->dev_count - 1) *
2738                          sizeof(struct kvm_io_range)), GFP_KERNEL);
2739        if (!new_bus)
2740                return -ENOMEM;
2741
2742        memcpy(new_bus, bus, sizeof(*bus) + i * sizeof(struct kvm_io_range));
2743        new_bus->dev_count--;
2744        memcpy(new_bus->range + i, bus->range + i + 1,
2745               (new_bus->dev_count - i) * sizeof(struct kvm_io_range));
2746
2747        rcu_assign_pointer(kvm->buses[bus_idx], new_bus);
2748        synchronize_srcu_expedited(&kvm->srcu);
2749        kfree(bus);
2750        return r;
2751}
2752
2753static struct notifier_block kvm_cpu_notifier = {
2754        .notifier_call = kvm_cpu_hotplug,
2755};
2756
2757static int vm_stat_get(void *_offset, u64 *val)
2758{
2759        unsigned offset = (long)_offset;
2760        struct kvm *kvm;
2761
2762        *val = 0;
2763        raw_spin_lock(&kvm_lock);
2764        list_for_each_entry(kvm, &vm_list, vm_list)
2765                *val += *(u32 *)((void *)kvm + offset);
2766        raw_spin_unlock(&kvm_lock);
2767        return 0;
2768}
2769
2770DEFINE_SIMPLE_ATTRIBUTE(vm_stat_fops, vm_stat_get, NULL, "%llu\n");
2771
2772static int vcpu_stat_get(void *_offset, u64 *val)
2773{
2774        unsigned offset = (long)_offset;
2775        struct kvm *kvm;
2776        struct kvm_vcpu *vcpu;
2777        int i;
2778
2779        *val = 0;
2780        raw_spin_lock(&kvm_lock);
2781        list_for_each_entry(kvm, &vm_list, vm_list)
2782                kvm_for_each_vcpu(i, vcpu, kvm)
2783                        *val += *(u32 *)((void *)vcpu + offset);
2784
2785        raw_spin_unlock(&kvm_lock);
2786        return 0;
2787}
2788
2789DEFINE_SIMPLE_ATTRIBUTE(vcpu_stat_fops, vcpu_stat_get, NULL, "%llu\n");
2790
2791static const struct file_operations *stat_fops[] = {
2792        [KVM_STAT_VCPU] = &vcpu_stat_fops,
2793        [KVM_STAT_VM]   = &vm_stat_fops,
2794};
2795
2796static int kvm_init_debug(void)
2797{
2798        int r = -EFAULT;
2799        struct kvm_stats_debugfs_item *p;
2800
2801        kvm_debugfs_dir = debugfs_create_dir("kvm", NULL);
2802        if (kvm_debugfs_dir == NULL)
2803                goto out;
2804
2805        for (p = debugfs_entries; p->name; ++p) {
2806                p->dentry = debugfs_create_file(p->name, 0444, kvm_debugfs_dir,
2807                                                (void *)(long)p->offset,
2808                                                stat_fops[p->kind]);
2809                if (p->dentry == NULL)
2810                        goto out_dir;
2811        }
2812
2813        return 0;
2814
2815out_dir:
2816        debugfs_remove_recursive(kvm_debugfs_dir);
2817out:
2818        return r;
2819}
2820
2821static void kvm_exit_debug(void)
2822{
2823        struct kvm_stats_debugfs_item *p;
2824
2825        for (p = debugfs_entries; p->name; ++p)
2826                debugfs_remove(p->dentry);
2827        debugfs_remove(kvm_debugfs_dir);
2828}
2829
2830static int kvm_suspend(void)
2831{
2832        if (kvm_usage_count)
2833                hardware_disable_nolock(NULL);
2834        return 0;
2835}
2836
2837static void kvm_resume(void)
2838{
2839        if (kvm_usage_count) {
2840                WARN_ON(raw_spin_is_locked(&kvm_lock));
2841                hardware_enable_nolock(NULL);
2842        }
2843}
2844
2845static struct syscore_ops kvm_syscore_ops = {
2846        .suspend = kvm_suspend,
2847        .resume = kvm_resume,
2848};
2849
2850static inline
2851struct kvm_vcpu *preempt_notifier_to_vcpu(struct preempt_notifier *pn)
2852{
2853        return container_of(pn, struct kvm_vcpu, preempt_notifier);
2854}
2855
2856static void kvm_sched_in(struct preempt_notifier *pn, int cpu)
2857{
2858        struct kvm_vcpu *vcpu = preempt_notifier_to_vcpu(pn);
2859
2860        kvm_arch_vcpu_load(vcpu, cpu);
2861}
2862
2863static void kvm_sched_out(struct preempt_notifier *pn,
2864                          struct task_struct *next)
2865{
2866        struct kvm_vcpu *vcpu = preempt_notifier_to_vcpu(pn);
2867
2868        kvm_arch_vcpu_put(vcpu);
2869}
2870
2871int kvm_init(void *opaque, unsigned vcpu_size, unsigned vcpu_align,
2872                  struct module *module)
2873{
2874        int r;
2875        int cpu;
2876
2877        r = kvm_arch_init(opaque);
2878        if (r)
2879                goto out_fail;
2880
2881        if (!zalloc_cpumask_var(&cpus_hardware_enabled, GFP_KERNEL)) {
2882                r = -ENOMEM;
2883                goto out_free_0;
2884        }
2885
2886        r = kvm_arch_hardware_setup();
2887        if (r < 0)
2888                goto out_free_0a;
2889
2890        for_each_online_cpu(cpu) {
2891                smp_call_function_single(cpu,
2892                                kvm_arch_check_processor_compat,
2893                                &r, 1);
2894                if (r < 0)
2895                        goto out_free_1;
2896        }
2897
2898        r = register_cpu_notifier(&kvm_cpu_notifier);
2899        if (r)
2900                goto out_free_2;
2901        register_reboot_notifier(&kvm_reboot_notifier);
2902
2903        /* A kmem cache lets us meet the alignment requirements of fx_save. */
2904        if (!vcpu_align)
2905                vcpu_align = __alignof__(struct kvm_vcpu);
2906        kvm_vcpu_cache = kmem_cache_create("kvm_vcpu", vcpu_size, vcpu_align,
2907                                           0, NULL);
2908        if (!kvm_vcpu_cache) {
2909                r = -ENOMEM;
2910                goto out_free_3;
2911        }
2912
2913        r = kvm_async_pf_init();
2914        if (r)
2915                goto out_free;
2916
2917        kvm_chardev_ops.owner = module;
2918        kvm_vm_fops.owner = module;
2919        kvm_vcpu_fops.owner = module;
2920
2921        r = misc_register(&kvm_dev);
2922        if (r) {
2923                printk(KERN_ERR "kvm: misc device register failed\n");
2924                goto out_unreg;
2925        }
2926
2927        register_syscore_ops(&kvm_syscore_ops);
2928
2929        kvm_preempt_ops.sched_in = kvm_sched_in;
2930        kvm_preempt_ops.sched_out = kvm_sched_out;
2931
2932        r = kvm_init_debug();
2933        if (r) {
2934                printk(KERN_ERR "kvm: create debugfs files failed\n");
2935                goto out_undebugfs;
2936        }
2937
2938        return 0;
2939
2940out_undebugfs:
2941        unregister_syscore_ops(&kvm_syscore_ops);
2942out_unreg:
2943        kvm_async_pf_deinit();
2944out_free:
2945        kmem_cache_destroy(kvm_vcpu_cache);
2946out_free_3:
2947        unregister_reboot_notifier(&kvm_reboot_notifier);
2948        unregister_cpu_notifier(&kvm_cpu_notifier);
2949out_free_2:
2950out_free_1:
2951        kvm_arch_hardware_unsetup();
2952out_free_0a:
2953        free_cpumask_var(cpus_hardware_enabled);
2954out_free_0:
2955        kvm_arch_exit();
2956out_fail:
2957        return r;
2958}
2959EXPORT_SYMBOL_GPL(kvm_init);
2960
2961void kvm_exit(void)
2962{
2963        kvm_exit_debug();
2964        misc_deregister(&kvm_dev);
2965        kmem_cache_destroy(kvm_vcpu_cache);
2966        kvm_async_pf_deinit();
2967        unregister_syscore_ops(&kvm_syscore_ops);
2968        unregister_reboot_notifier(&kvm_reboot_notifier);
2969        unregister_cpu_notifier(&kvm_cpu_notifier);
2970        on_each_cpu(hardware_disable_nolock, NULL, 1);
2971        kvm_arch_hardware_unsetup();
2972        kvm_arch_exit();
2973        free_cpumask_var(cpus_hardware_enabled);
2974}
2975EXPORT_SYMBOL_GPL(kvm_exit);
2976
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