virt/kvm/kvm_main.c

   1 /*
   2  * Kernel-based Virtual Machine driver for Linux
   3  *
   4  * This module enables machines with Intel VT-x extensions to run virtual
   5  * machines without emulation or binary translation.
   6  *
   7  * Copyright (C) 2006 Qumranet, Inc.
   8  *
   9  * Authors:
  10  *   Avi Kivity   <avi@qumranet.com>
  11  *   Yaniv Kamay  <yaniv@qumranet.com>
  12  *
  13  * This work is licensed under the terms of the GNU GPL, version 2.  See
  14  * the COPYING file in the top-level directory.
  15  *
  16  */
  17
  18 #include "iodev.h"
  19
  20 #include <linux/kvm_host.h>
  21 #include <linux/kvm.h>
  22 #include <linux/module.h>
  23 #include <linux/errno.h>
  24 #include <linux/percpu.h>
  25 #include <linux/gfp.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/sysdev.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
  44 #include <asm/processor.h>
  45 #include <asm/io.h>
  46 #include <asm/uaccess.h>
  47 #include <asm/pgtable.h>
  48
  49 MODULE_AUTHOR("Qumranet");
  50 MODULE_LICENSE("GPL");
  51
  52 DEFINE_SPINLOCK(kvm_lock);
  53 LIST_HEAD(vm_list);
  54
  55 static cpumask_t cpus_hardware_enabled;
  56
  57 struct kmem_cache *kvm_vcpu_cache;
  58 EXPORT_SYMBOL_GPL(kvm_vcpu_cache);
  59
  60 static __read_mostly struct preempt_ops kvm_preempt_ops;
  61
  62 static struct dentry *debugfs_dir;
  63
  64 static long kvm_vcpu_ioctl(struct file *file, unsigned int ioctl,
  65                            unsigned long arg);
  66
  67 static inline int valid_vcpu(int n)
  68 {
  69         return likely(n >= 0 && n < KVM_MAX_VCPUS);
  70 }
  71
  72 /*
  73  * Switches to specified vcpu, until a matching vcpu_put()
  74  */
  75 void vcpu_load(struct kvm_vcpu *vcpu)
  76 {
  77         int cpu;
  78
  79         mutex_lock(&vcpu->mutex);
  80         cpu = get_cpu();
  81         preempt_notifier_register(&vcpu->preempt_notifier);
  82         kvm_arch_vcpu_load(vcpu, cpu);
  83         put_cpu();
  84 }
  85
  86 void vcpu_put(struct kvm_vcpu *vcpu)
  87 {
  88         preempt_disable();
  89         kvm_arch_vcpu_put(vcpu);
  90         preempt_notifier_unregister(&vcpu->preempt_notifier);
  91         preempt_enable();
  92         mutex_unlock(&vcpu->mutex);
  93 }
  94
  95 static void ack_flush(void *_completed)
  96 {
  97 }
  98
  99 void kvm_flush_remote_tlbs(struct kvm *kvm)
 100 {
 101         int i, cpu;
 102         cpumask_t cpus;
 103         struct kvm_vcpu *vcpu;
 104
 105         cpus_clear(cpus);
 106         for (i = 0; i < KVM_MAX_VCPUS; ++i) {
 107                 vcpu = kvm->vcpus[i];
 108                 if (!vcpu)
 109                         continue;
 110                 if (test_and_set_bit(KVM_REQ_TLB_FLUSH, &vcpu->requests))
 111                         continue;
 112                 cpu = vcpu->cpu;
 113                 if (cpu != -1 && cpu != raw_smp_processor_id())
 114                         cpu_set(cpu, cpus);
 115         }
 116         if (cpus_empty(cpus))
 117                 return;
 118         ++kvm->stat.remote_tlb_flush;
 119         smp_call_function_mask(cpus, ack_flush, NULL, 1);
 120 }
 121
 122 int kvm_vcpu_init(struct kvm_vcpu *vcpu, struct kvm *kvm, unsigned id)
 123 {
 124         struct page *page;
 125         int r;
 126
 127         mutex_init(&vcpu->mutex);
 128         vcpu->cpu = -1;
 129         vcpu->kvm = kvm;
 130         vcpu->vcpu_id = id;
 131         init_waitqueue_head(&vcpu->wq);
 132
 133         page = alloc_page(GFP_KERNEL | __GFP_ZERO);
 134         if (!page) {
 135                 r = -ENOMEM;
 136                 goto fail;
 137         }
 138         vcpu->run = page_address(page);
 139
 140         r = kvm_arch_vcpu_init(vcpu);
 141         if (r < 0)
 142                 goto fail_free_run;
 143         return 0;
 144
 145 fail_free_run:
 146         free_page((unsigned long)vcpu->run);
 147 fail:
 148         return r;
 149 }
 150 EXPORT_SYMBOL_GPL(kvm_vcpu_init);
 151
 152 void kvm_vcpu_uninit(struct kvm_vcpu *vcpu)
 153 {
 154         kvm_arch_vcpu_uninit(vcpu);
 155         free_page((unsigned long)vcpu->run);
 156 }
 157 EXPORT_SYMBOL_GPL(kvm_vcpu_uninit);
 158
 159 static struct kvm *kvm_create_vm(void)
 160 {
 161         struct kvm *kvm = kvm_arch_create_vm();
 162
 163         if (IS_ERR(kvm))
 164                 goto out;
 165
 166         kvm->mm = current->mm;
 167         atomic_inc(&kvm->mm->mm_count);
 168         spin_lock_init(&kvm->mmu_lock);
 169         kvm_io_bus_init(&kvm->pio_bus);
 170         mutex_init(&kvm->lock);
 171         kvm_io_bus_init(&kvm->mmio_bus);
 172         spin_lock(&kvm_lock);
 173         list_add(&kvm->vm_list, &vm_list);
 174         spin_unlock(&kvm_lock);
 175 out:
 176         return kvm;
 177 }
 178
 179 /*
 180  * Free any memory in @free but not in @dont.
 181  */
 182 static void kvm_free_physmem_slot(struct kvm_memory_slot *free,
 183                                   struct kvm_memory_slot *dont)
 184 {
 185         if (!dont || free->rmap != dont->rmap)
 186                 vfree(free->rmap);
 187
 188         if (!dont || free->dirty_bitmap != dont->dirty_bitmap)
 189                 vfree(free->dirty_bitmap);
 190
 191         free->npages = 0;
 192         free->dirty_bitmap = NULL;
 193         free->rmap = NULL;
 194 }
 195
 196 void kvm_free_physmem(struct kvm *kvm)
 197 {
 198         int i;
 199
 200         for (i = 0; i < kvm->nmemslots; ++i)
 201                 kvm_free_physmem_slot(&kvm->memslots[i], NULL);
 202 }
 203
 204 static void kvm_destroy_vm(struct kvm *kvm)
 205 {
 206         struct mm_struct *mm = kvm->mm;
 207
 208         spin_lock(&kvm_lock);
 209         list_del(&kvm->vm_list);
 210         spin_unlock(&kvm_lock);
 211         kvm_io_bus_destroy(&kvm->pio_bus);
 212         kvm_io_bus_destroy(&kvm->mmio_bus);
 213         kvm_arch_destroy_vm(kvm);
 214         mmdrop(mm);
 215 }
 216
 217 static int kvm_vm_release(struct inode *inode, struct file *filp)
 218 {
 219         struct kvm *kvm = filp->private_data;
 220
 221         kvm_destroy_vm(kvm);
 222         return 0;
 223 }
 224
 225 /*
 226  * Allocate some memory and give it an address in the guest physical address
 227  * space.
 228  *
 229  * Discontiguous memory is allowed, mostly for framebuffers.
 230  *
 231  * Must be called holding mmap_sem for write.
 232  */
 233 int __kvm_set_memory_region(struct kvm *kvm,
 234                             struct kvm_userspace_memory_region *mem,
 235                             int user_alloc)
 236 {
 237         int r;
 238         gfn_t base_gfn;
 239         unsigned long npages;
 240         unsigned long i;
 241         struct kvm_memory_slot *memslot;
 242         struct kvm_memory_slot old, new;
 243
 244         r = -EINVAL;
 245         /* General sanity checks */
 246         if (mem->memory_size & (PAGE_SIZE - 1))
 247                 goto out;
 248         if (mem->guest_phys_addr & (PAGE_SIZE - 1))
 249                 goto out;
 250         if (mem->slot >= KVM_MEMORY_SLOTS + KVM_PRIVATE_MEM_SLOTS)
 251                 goto out;
 252         if (mem->guest_phys_addr + mem->memory_size < mem->guest_phys_addr)
 253                 goto out;
 254
 255         memslot = &kvm->memslots[mem->slot];
 256         base_gfn = mem->guest_phys_addr >> PAGE_SHIFT;
 257         npages = mem->memory_size >> PAGE_SHIFT;
 258
 259         if (!npages)
 260                 mem->flags &= ~KVM_MEM_LOG_DIRTY_PAGES;
 261
 262         new = old = *memslot;
 263
 264         new.base_gfn = base_gfn;
 265         new.npages = npages;
 266         new.flags = mem->flags;
 267
 268         /* Disallow changing a memory slot's size. */
 269         r = -EINVAL;
 270         if (npages && old.npages && npages != old.npages)
 271                 goto out_free;
 272
 273         /* Check for overlaps */
 274         r = -EEXIST;
 275         for (i = 0; i < KVM_MEMORY_SLOTS; ++i) {
 276                 struct kvm_memory_slot *s = &kvm->memslots[i];
 277
 278                 if (s == memslot)
 279                         continue;
 280                 if (!((base_gfn + npages <= s->base_gfn) ||
 281                       (base_gfn >= s->base_gfn + s->npages)))
 282                         goto out_free;
 283         }
 284
 285         /* Free page dirty bitmap if unneeded */
 286         if (!(new.flags & KVM_MEM_LOG_DIRTY_PAGES))
 287                 new.dirty_bitmap = NULL;
 288
 289         r = -ENOMEM;
 290
 291         /* Allocate if a slot is being created */
 292         if (npages && !new.rmap) {
 293                 new.rmap = vmalloc(npages * sizeof(struct page *));
 294
 295                 if (!new.rmap)
 296                         goto out_free;
 297
 298                 memset(new.rmap, 0, npages * sizeof(*new.rmap));
 299
 300                 new.user_alloc = user_alloc;
 301                 new.userspace_addr = mem->userspace_addr;
 302         }
 303
 304         /* Allocate page dirty bitmap if needed */
 305         if ((new.flags & KVM_MEM_LOG_DIRTY_PAGES) && !new.dirty_bitmap) {
 306                 unsigned dirty_bytes = ALIGN(npages, BITS_PER_LONG) / 8;
 307
 308                 new.dirty_bitmap = vmalloc(dirty_bytes);
 309                 if (!new.dirty_bitmap)
 310                         goto out_free;
 311                 memset(new.dirty_bitmap, 0, dirty_bytes);
 312         }
 313
 314         if (mem->slot >= kvm->nmemslots)
 315                 kvm->nmemslots = mem->slot + 1;
 316
 317         *memslot = new;
 318
 319         r = kvm_arch_set_memory_region(kvm, mem, old, user_alloc);
 320         if (r) {
 321                 *memslot = old;
 322                 goto out_free;
 323         }
 324
 325         kvm_free_physmem_slot(&old, &new);
 326         return 0;
 327
 328 out_free:
 329         kvm_free_physmem_slot(&new, &old);
 330 out:
 331         return r;
 332
 333 }
 334 EXPORT_SYMBOL_GPL(__kvm_set_memory_region);
 335
 336 int kvm_set_memory_region(struct kvm *kvm,
 337                           struct kvm_userspace_memory_region *mem,
 338                           int user_alloc)
 339 {
 340         int r;
 341
 342         down_write(&current->mm->mmap_sem);
 343         r = __kvm_set_memory_region(kvm, mem, user_alloc);
 344         up_write(&current->mm->mmap_sem);
 345         return r;
 346 }
 347 EXPORT_SYMBOL_GPL(kvm_set_memory_region);
 348
 349 int kvm_vm_ioctl_set_memory_region(struct kvm *kvm,
 350                                    struct
 351                                    kvm_userspace_memory_region *mem,
 352                                    int user_alloc)
 353 {
 354         if (mem->slot >= KVM_MEMORY_SLOTS)
 355                 return -EINVAL;
 356         return kvm_set_memory_region(kvm, mem, user_alloc);
 357 }
 358
 359 int kvm_get_dirty_log(struct kvm *kvm,
 360                         struct kvm_dirty_log *log, int *is_dirty)
 361 {
 362         struct kvm_memory_slot *memslot;
 363         int r, i;
 364         int n;
 365         unsigned long any = 0;
 366
 367         r = -EINVAL;
 368         if (log->slot >= KVM_MEMORY_SLOTS)
 369                 goto out;
 370
 371         memslot = &kvm->memslots[log->slot];
 372         r = -ENOENT;
 373         if (!memslot->dirty_bitmap)
 374                 goto out;
 375
 376         n = ALIGN(memslot->npages, BITS_PER_LONG) / 8;
 377
 378         for (i = 0; !any && i < n/sizeof(long); ++i)
 379                 any = memslot->dirty_bitmap[i];
 380
 381         r = -EFAULT;
 382         if (copy_to_user(log->dirty_bitmap, memslot->dirty_bitmap, n))
 383                 goto out;
 384
 385         if (any)
 386                 *is_dirty = 1;
 387
 388         r = 0;
 389 out:
 390         return r;
 391 }
 392
 393 int is_error_page(struct page *page)
 394 {
 395         return page == bad_page;
 396 }
 397 EXPORT_SYMBOL_GPL(is_error_page);
 398
 399 static inline unsigned long bad_hva(void)
 400 {
 401         return PAGE_OFFSET;
 402 }
 403
 404 int kvm_is_error_hva(unsigned long addr)
 405 {
 406         return addr == bad_hva();
 407 }
 408 EXPORT_SYMBOL_GPL(kvm_is_error_hva);
 409
 410 static struct kvm_memory_slot *__gfn_to_memslot(struct kvm *kvm, gfn_t gfn)
 411 {
 412         int i;
 413
 414         for (i = 0; i < kvm->nmemslots; ++i) {
 415                 struct kvm_memory_slot *memslot = &kvm->memslots[i];
 416
 417                 if (gfn >= memslot->base_gfn
 418                     && gfn < memslot->base_gfn + memslot->npages)
 419                         return memslot;
 420         }
 421         return NULL;
 422 }
 423
 424 struct kvm_memory_slot *gfn_to_memslot(struct kvm *kvm, gfn_t gfn)
 425 {
 426         gfn = unalias_gfn(kvm, gfn);
 427         return __gfn_to_memslot(kvm, gfn);
 428 }
 429
 430 int kvm_is_visible_gfn(struct kvm *kvm, gfn_t gfn)
 431 {
 432         int i;
 433
 434         gfn = unalias_gfn(kvm, gfn);
 435         for (i = 0; i < KVM_MEMORY_SLOTS; ++i) {
 436                 struct kvm_memory_slot *memslot = &kvm->memslots[i];
 437
 438                 if (gfn >= memslot->base_gfn
 439                     && gfn < memslot->base_gfn + memslot->npages)
 440                         return 1;
 441         }
 442         return 0;
 443 }
 444 EXPORT_SYMBOL_GPL(kvm_is_visible_gfn);
 445
 446 static unsigned long gfn_to_hva(struct kvm *kvm, gfn_t gfn)
 447 {
 448         struct kvm_memory_slot *slot;
 449
 450         gfn = unalias_gfn(kvm, gfn);
 451         slot = __gfn_to_memslot(kvm, gfn);
 452         if (!slot)
 453                 return bad_hva();
 454         return (slot->userspace_addr + (gfn - slot->base_gfn) * PAGE_SIZE);
 455 }
 456
 457 /*
 458  * Requires current->mm->mmap_sem to be held
 459  */
 460 struct page *gfn_to_page(struct kvm *kvm, gfn_t gfn)
 461 {
 462         struct page *page[1];
 463         unsigned long addr;
 464         int npages;
 465
 466         might_sleep();
 467
 468         addr = gfn_to_hva(kvm, gfn);
 469         if (kvm_is_error_hva(addr)) {
 470                 get_page(bad_page);
 471                 return bad_page;
 472         }
 473
 474         npages = get_user_pages(current, current->mm, addr, 1, 1, 1, page,
 475                                 NULL);
 476
 477         if (npages != 1) {
 478                 get_page(bad_page);
 479                 return bad_page;
 480         }
 481
 482         return page[0];
 483 }
 484
 485 EXPORT_SYMBOL_GPL(gfn_to_page);
 486
 487 void kvm_release_page_clean(struct page *page)
 488 {
 489         put_page(page);
 490 }
 491 EXPORT_SYMBOL_GPL(kvm_release_page_clean);
 492
 493 void kvm_release_page_dirty(struct page *page)
 494 {
 495         if (!PageReserved(page))
 496                 SetPageDirty(page);
 497         put_page(page);
 498 }
 499 EXPORT_SYMBOL_GPL(kvm_release_page_dirty);
 500
 501 static int next_segment(unsigned long len, int offset)
 502 {
 503         if (len > PAGE_SIZE - offset)
 504                 return PAGE_SIZE - offset;
 505         else
 506                 return len;
 507 }
 508
 509 int kvm_read_guest_page(struct kvm *kvm, gfn_t gfn, void *data, int offset,
 510                         int len)
 511 {
 512         int r;
 513         unsigned long addr;
 514
 515         addr = gfn_to_hva(kvm, gfn);
 516         if (kvm_is_error_hva(addr))
 517                 return -EFAULT;
 518         r = copy_from_user(data, (void __user *)addr + offset, len);
 519         if (r)
 520                 return -EFAULT;
 521         return 0;
 522 }
 523 EXPORT_SYMBOL_GPL(kvm_read_guest_page);
 524
 525 int kvm_read_guest(struct kvm *kvm, gpa_t gpa, void *data, unsigned long len)
 526 {
 527         gfn_t gfn = gpa >> PAGE_SHIFT;
 528         int seg;
 529         int offset = offset_in_page(gpa);
 530         int ret;
 531
 532         while ((seg = next_segment(len, offset)) != 0) {
 533                 ret = kvm_read_guest_page(kvm, gfn, data, offset, seg);
 534                 if (ret < 0)
 535                         return ret;
 536                 offset = 0;
 537                 len -= seg;
 538                 data += seg;
 539                 ++gfn;
 540         }
 541         return 0;
 542 }
 543 EXPORT_SYMBOL_GPL(kvm_read_guest);
 544
 545 int kvm_read_guest_atomic(struct kvm *kvm, gpa_t gpa, void *data,
 546                           unsigned long len)
 547 {
 548         int r;
 549         unsigned long addr;
 550         gfn_t gfn = gpa >> PAGE_SHIFT;
 551         int offset = offset_in_page(gpa);
 552
 553         addr = gfn_to_hva(kvm, gfn);
 554         if (kvm_is_error_hva(addr))
 555                 return -EFAULT;
 556         r = __copy_from_user_inatomic(data, (void __user *)addr + offset, len);
 557         if (r)
 558                 return -EFAULT;
 559         return 0;
 560 }
 561 EXPORT_SYMBOL(kvm_read_guest_atomic);
 562
 563 int kvm_write_guest_page(struct kvm *kvm, gfn_t gfn, const void *data,
 564                          int offset, int len)
 565 {
 566         int r;
 567         unsigned long addr;
 568
 569         addr = gfn_to_hva(kvm, gfn);
 570         if (kvm_is_error_hva(addr))
 571                 return -EFAULT;
 572         r = copy_to_user((void __user *)addr + offset, data, len);
 573         if (r)
 574                 return -EFAULT;
 575         mark_page_dirty(kvm, gfn);
 576         return 0;
 577 }
 578 EXPORT_SYMBOL_GPL(kvm_write_guest_page);
 579
 580 int kvm_write_guest(struct kvm *kvm, gpa_t gpa, const void *data,
 581                     unsigned long len)
 582 {
 583         gfn_t gfn = gpa >> PAGE_SHIFT;
 584         int seg;
 585         int offset = offset_in_page(gpa);
 586         int ret;
 587
 588         while ((seg = next_segment(len, offset)) != 0) {
 589                 ret = kvm_write_guest_page(kvm, gfn, data, offset, seg);
 590                 if (ret < 0)
 591                         return ret;
 592                 offset = 0;
 593                 len -= seg;
 594                 data += seg;
 595                 ++gfn;
 596         }
 597         return 0;
 598 }
 599
 600 int kvm_clear_guest_page(struct kvm *kvm, gfn_t gfn, int offset, int len)
 601 {
 602         return kvm_write_guest_page(kvm, gfn, empty_zero_page, offset, len);
 603 }
 604 EXPORT_SYMBOL_GPL(kvm_clear_guest_page);
 605
 606 int kvm_clear_guest(struct kvm *kvm, gpa_t gpa, unsigned long len)
 607 {
 608         gfn_t gfn = gpa >> PAGE_SHIFT;
 609         int seg;
 610         int offset = offset_in_page(gpa);
 611         int ret;
 612
 613         while ((seg = next_segment(len, offset)) != 0) {
 614                 ret = kvm_clear_guest_page(kvm, gfn, offset, seg);
 615                 if (ret < 0)
 616                         return ret;
 617                 offset = 0;
 618                 len -= seg;
 619                 ++gfn;
 620         }
 621         return 0;
 622 }
 623 EXPORT_SYMBOL_GPL(kvm_clear_guest);
 624
 625 void mark_page_dirty(struct kvm *kvm, gfn_t gfn)
 626 {
 627         struct kvm_memory_slot *memslot;
 628
 629         gfn = unalias_gfn(kvm, gfn);
 630         memslot = __gfn_to_memslot(kvm, gfn);
 631         if (memslot && memslot->dirty_bitmap) {
 632                 unsigned long rel_gfn = gfn - memslot->base_gfn;
 633
 634                 /* avoid RMW */
 635                 if (!test_bit(rel_gfn, memslot->dirty_bitmap))
 636                         set_bit(rel_gfn, memslot->dirty_bitmap);
 637         }
 638 }
 639
 640 /*
 641  * The vCPU has executed a HLT instruction with in-kernel mode enabled.
 642  */
 643 void kvm_vcpu_block(struct kvm_vcpu *vcpu)
 644 {
 645         DECLARE_WAITQUEUE(wait, current);
 646
 647         add_wait_queue(&vcpu->wq, &wait);
 648
 649         /*
 650          * We will block until either an interrupt or a signal wakes us up
 651          */
 652         while (!kvm_cpu_has_interrupt(vcpu)
 653                && !signal_pending(current)
 654                && !kvm_arch_vcpu_runnable(vcpu)) {
 655                 set_current_state(TASK_INTERRUPTIBLE);
 656                 vcpu_put(vcpu);
 657                 schedule();
 658                 vcpu_load(vcpu);
 659         }
 660
 661         __set_current_state(TASK_RUNNING);
 662         remove_wait_queue(&vcpu->wq, &wait);
 663 }
 664
 665 void kvm_resched(struct kvm_vcpu *vcpu)
 666 {
 667         if (!need_resched())
 668                 return;
 669         cond_resched();
 670 }
 671 EXPORT_SYMBOL_GPL(kvm_resched);
 672
 673 static int kvm_vcpu_fault(struct vm_area_struct *vma, struct vm_fault *vmf)
 674 {
 675         struct kvm_vcpu *vcpu = vma->vm_file->private_data;
 676         struct page *page;
 677
 678         if (vmf->pgoff == 0)
 679                 page = virt_to_page(vcpu->run);
 680         else if (vmf->pgoff == KVM_PIO_PAGE_OFFSET)
 681                 page = virt_to_page(vcpu->arch.pio_data);
 682         else
 683                 return VM_FAULT_SIGBUS;
 684         get_page(page);
 685         vmf->page = page;
 686         return 0;
 687 }
 688
 689 static struct vm_operations_struct kvm_vcpu_vm_ops = {
 690         .fault = kvm_vcpu_fault,
 691 };
 692
 693 static int kvm_vcpu_mmap(struct file *file, struct vm_area_struct *vma)
 694 {
 695         vma->vm_ops = &kvm_vcpu_vm_ops;
 696         return 0;
 697 }
 698
 699 static int kvm_vcpu_release(struct inode *inode, struct file *filp)
 700 {
 701         struct kvm_vcpu *vcpu = filp->private_data;
 702
 703         fput(vcpu->kvm->filp);
 704         return 0;
 705 }
 706
 707 static struct file_operations kvm_vcpu_fops = {
 708         .release        = kvm_vcpu_release,
 709         .unlocked_ioctl = kvm_vcpu_ioctl,
 710         .compat_ioctl   = kvm_vcpu_ioctl,
 711         .mmap           = kvm_vcpu_mmap,
 712 };
 713
 714 /*
 715  * Allocates an inode for the vcpu.
 716  */
 717 static int create_vcpu_fd(struct kvm_vcpu *vcpu)
 718 {
 719         int fd, r;
 720         struct inode *inode;
 721         struct file *file;
 722
 723         r = anon_inode_getfd(&fd, &inode, &file,
 724                              "kvm-vcpu", &kvm_vcpu_fops, vcpu);
 725         if (r)
 726                 return r;
 727         atomic_inc(&vcpu->kvm->filp->f_count);
 728         return fd;
 729 }
 730
 731 /*
 732  * Creates some virtual cpus.  Good luck creating more than one.
 733  */
 734 static int kvm_vm_ioctl_create_vcpu(struct kvm *kvm, int n)
 735 {
 736         int r;
 737         struct kvm_vcpu *vcpu;
 738
 739         if (!valid_vcpu(n))
 740                 return -EINVAL;
 741
 742         vcpu = kvm_arch_vcpu_create(kvm, n);
 743         if (IS_ERR(vcpu))
 744                 return PTR_ERR(vcpu);
 745
 746         preempt_notifier_init(&vcpu->preempt_notifier, &kvm_preempt_ops);
 747
 748         r = kvm_arch_vcpu_setup(vcpu);
 749         if (r)
 750                 goto vcpu_destroy;
 751
 752         mutex_lock(&kvm->lock);
 753         if (kvm->vcpus[n]) {
 754                 r = -EEXIST;
 755                 mutex_unlock(&kvm->lock);
 756                 goto vcpu_destroy;
 757         }
 758         kvm->vcpus[n] = vcpu;
 759         mutex_unlock(&kvm->lock);
 760
 761         /* Now it's all set up, let userspace reach it */
 762         r = create_vcpu_fd(vcpu);
 763         if (r < 0)
 764                 goto unlink;
 765         return r;
 766
 767 unlink:
 768         mutex_lock(&kvm->lock);
 769         kvm->vcpus[n] = NULL;
 770         mutex_unlock(&kvm->lock);
 771 vcpu_destroy:
 772         kvm_arch_vcpu_destroy(vcpu);
 773         return r;
 774 }
 775
 776 static int kvm_vcpu_ioctl_set_sigmask(struct kvm_vcpu *vcpu, sigset_t *sigset)
 777 {
 778         if (sigset) {
 779                 sigdelsetmask(sigset, sigmask(SIGKILL)|sigmask(SIGSTOP));
 780                 vcpu->sigset_active = 1;
 781                 vcpu->sigset = *sigset;
 782         } else
 783                 vcpu->sigset_active = 0;
 784         return 0;
 785 }
 786
 787 static long kvm_vcpu_ioctl(struct file *filp,
 788                            unsigned int ioctl, unsigned long arg)
 789 {
 790         struct kvm_vcpu *vcpu = filp->private_data;
 791         void __user *argp = (void __user *)arg;
 792         int r;
 793
 794         if (vcpu->kvm->mm != current->mm)
 795                 return -EIO;
 796         switch (ioctl) {
 797         case KVM_RUN:
 798                 r = -EINVAL;
 799                 if (arg)
 800                         goto out;
 801                 r = kvm_arch_vcpu_ioctl_run(vcpu, vcpu->run);
 802                 break;
 803         case KVM_GET_REGS: {
 804                 struct kvm_regs kvm_regs;
 805
 806                 memset(&kvm_regs, 0, sizeof kvm_regs);
 807                 r = kvm_arch_vcpu_ioctl_get_regs(vcpu, &kvm_regs);
 808                 if (r)
 809                         goto out;
 810                 r = -EFAULT;
 811                 if (copy_to_user(argp, &kvm_regs, sizeof kvm_regs))
 812                         goto out;
 813                 r = 0;
 814                 break;
 815         }
 816         case KVM_SET_REGS: {
 817                 struct kvm_regs kvm_regs;
 818
 819                 r = -EFAULT;
 820                 if (copy_from_user(&kvm_regs, argp, sizeof kvm_regs))
 821                         goto out;
 822                 r = kvm_arch_vcpu_ioctl_set_regs(vcpu, &kvm_regs);
 823                 if (r)
 824                         goto out;
 825                 r = 0;
 826                 break;
 827         }
 828         case KVM_GET_SREGS: {
 829                 struct kvm_sregs kvm_sregs;
 830
 831                 memset(&kvm_sregs, 0, sizeof kvm_sregs);
 832                 r = kvm_arch_vcpu_ioctl_get_sregs(vcpu, &kvm_sregs);
 833                 if (r)
 834                         goto out;
 835                 r = -EFAULT;
 836                 if (copy_to_user(argp, &kvm_sregs, sizeof kvm_sregs))
 837                         goto out;
 838                 r = 0;
 839                 break;
 840         }
 841         case KVM_SET_SREGS: {
 842                 struct kvm_sregs kvm_sregs;
 843
 844                 r = -EFAULT;
 845                 if (copy_from_user(&kvm_sregs, argp, sizeof kvm_sregs))
 846                         goto out;
 847                 r = kvm_arch_vcpu_ioctl_set_sregs(vcpu, &kvm_sregs);
 848                 if (r)
 849                         goto out;
 850                 r = 0;
 851                 break;
 852         }
 853         case KVM_TRANSLATE: {
 854                 struct kvm_translation tr;
 855
 856                 r = -EFAULT;
 857                 if (copy_from_user(&tr, argp, sizeof tr))
 858                         goto out;
 859                 r = kvm_arch_vcpu_ioctl_translate(vcpu, &tr);
 860                 if (r)
 861                         goto out;
 862                 r = -EFAULT;
 863                 if (copy_to_user(argp, &tr, sizeof tr))
 864                         goto out;
 865                 r = 0;
 866                 break;
 867         }
 868         case KVM_DEBUG_GUEST: {
 869                 struct kvm_debug_guest dbg;
 870
 871                 r = -EFAULT;
 872                 if (copy_from_user(&dbg, argp, sizeof dbg))
 873                         goto out;
 874                 r = kvm_arch_vcpu_ioctl_debug_guest(vcpu, &dbg);
 875                 if (r)
 876                         goto out;
 877                 r = 0;
 878                 break;
 879         }
 880         case KVM_SET_SIGNAL_MASK: {
 881                 struct kvm_signal_mask __user *sigmask_arg = argp;
 882                 struct kvm_signal_mask kvm_sigmask;
 883                 sigset_t sigset, *p;
 884
 885                 p = NULL;
 886                 if (argp) {
 887                         r = -EFAULT;
 888                         if (copy_from_user(&kvm_sigmask, argp,
 889                                            sizeof kvm_sigmask))
 890                                 goto out;
 891                         r = -EINVAL;
 892                         if (kvm_sigmask.len != sizeof sigset)
 893                                 goto out;
 894                         r = -EFAULT;
 895                         if (copy_from_user(&sigset, sigmask_arg->sigset,
 896                                            sizeof sigset))
 897                                 goto out;
 898                         p = &sigset;
 899                 }
 900                 r = kvm_vcpu_ioctl_set_sigmask(vcpu, &sigset);
 901                 break;
 902         }
 903         case KVM_GET_FPU: {
 904                 struct kvm_fpu fpu;
 905
 906                 memset(&fpu, 0, sizeof fpu);
 907                 r = kvm_arch_vcpu_ioctl_get_fpu(vcpu, &fpu);
 908                 if (r)
 909                         goto out;
 910                 r = -EFAULT;
 911                 if (copy_to_user(argp, &fpu, sizeof fpu))
 912                         goto out;
 913                 r = 0;
 914                 break;
 915         }
 916         case KVM_SET_FPU: {
 917                 struct kvm_fpu fpu;
 918
 919                 r = -EFAULT;
 920                 if (copy_from_user(&fpu, argp, sizeof fpu))
 921                         goto out;
 922                 r = kvm_arch_vcpu_ioctl_set_fpu(vcpu, &fpu);
 923                 if (r)
 924                         goto out;
 925                 r = 0;
 926                 break;
 927         }
 928         default:
 929                 r = kvm_arch_vcpu_ioctl(filp, ioctl, arg);
 930         }
 931 out:
 932         return r;
 933 }
 934
 935 static long kvm_vm_ioctl(struct file *filp,
 936                            unsigned int ioctl, unsigned long arg)
 937 {
 938         struct kvm *kvm = filp->private_data;
 939         void __user *argp = (void __user *)arg;
 940         int r;
 941
 942         if (kvm->mm != current->mm)
 943                 return -EIO;
 944         switch (ioctl) {
 945         case KVM_CREATE_VCPU:
 946                 r = kvm_vm_ioctl_create_vcpu(kvm, arg);
 947                 if (r < 0)
 948                         goto out;
 949                 break;
 950         case KVM_SET_USER_MEMORY_REGION: {
 951                 struct kvm_userspace_memory_region kvm_userspace_mem;
 952
 953                 r = -EFAULT;
 954                 if (copy_from_user(&kvm_userspace_mem, argp,
 955                                                 sizeof kvm_userspace_mem))
 956                         goto out;
 957
 958                 r = kvm_vm_ioctl_set_memory_region(kvm, &kvm_userspace_mem, 1);
 959                 if (r)
 960                         goto out;
 961                 break;
 962         }
 963         case KVM_GET_DIRTY_LOG: {
 964                 struct kvm_dirty_log log;
 965
 966                 r = -EFAULT;
 967                 if (copy_from_user(&log, argp, sizeof log))
 968                         goto out;
 969                 r = kvm_vm_ioctl_get_dirty_log(kvm, &log);
 970                 if (r)
 971                         goto out;
 972                 break;
 973         }
 974         default:
 975                 r = kvm_arch_vm_ioctl(filp, ioctl, arg);
 976         }
 977 out:
 978         return r;
 979 }
 980
 981 static int kvm_vm_fault(struct vm_area_struct *vma, struct vm_fault *vmf)
 982 {
 983         struct kvm *kvm = vma->vm_file->private_data;
 984         struct page *page;
 985
 986         if (!kvm_is_visible_gfn(kvm, vmf->pgoff))
 987                 return VM_FAULT_SIGBUS;
 988         page = gfn_to_page(kvm, vmf->pgoff);
 989         if (is_error_page(page)) {
 990                 kvm_release_page_clean(page);
 991                 return VM_FAULT_SIGBUS;
 992         }
 993         vmf->page = page;
 994         return 0;
 995 }
 996
 997 static struct vm_operations_struct kvm_vm_vm_ops = {
 998         .fault = kvm_vm_fault,
 999 };
1000
1001 static int kvm_vm_mmap(struct file *file, struct vm_area_struct *vma)
1002 {
1003         vma->vm_ops = &kvm_vm_vm_ops;
1004         return 0;
1005 }
1006
1007 static struct file_operations kvm_vm_fops = {
1008         .release        = kvm_vm_release,
1009         .unlocked_ioctl = kvm_vm_ioctl,
1010         .compat_ioctl   = kvm_vm_ioctl,
1011         .mmap           = kvm_vm_mmap,
1012 };
1013
1014 static int kvm_dev_ioctl_create_vm(void)
1015 {
1016         int fd, r;
1017         struct inode *inode;
1018         struct file *file;
1019         struct kvm *kvm;
1020
1021         kvm = kvm_create_vm();
1022         if (IS_ERR(kvm))
1023                 return PTR_ERR(kvm);
1024         r = anon_inode_getfd(&fd, &inode, &file, "kvm-vm", &kvm_vm_fops, kvm);
1025         if (r) {
1026                 kvm_destroy_vm(kvm);
1027                 return r;
1028         }
1029
1030         kvm->filp = file;
1031
1032         return fd;
1033 }
1034
1035 static long kvm_dev_ioctl(struct file *filp,
1036                           unsigned int ioctl, unsigned long arg)
1037 {
1038         void __user *argp = (void __user *)arg;
1039         long r = -EINVAL;
1040
1041         switch (ioctl) {
1042         case KVM_GET_API_VERSION:
1043                 r = -EINVAL;
1044                 if (arg)
1045                         goto out;
1046                 r = KVM_API_VERSION;
1047                 break;
1048         case KVM_CREATE_VM:
1049                 r = -EINVAL;
1050                 if (arg)
1051                         goto out;
1052                 r = kvm_dev_ioctl_create_vm();
1053                 break;
1054         case KVM_CHECK_EXTENSION:
1055                 r = kvm_dev_ioctl_check_extension((long)argp);
1056                 break;
1057         case KVM_GET_VCPU_MMAP_SIZE:
1058                 r = -EINVAL;
1059                 if (arg)
1060                         goto out;
1061                 r = 2 * PAGE_SIZE;
1062                 break;
1063         default:
1064                 return kvm_arch_dev_ioctl(filp, ioctl, arg);
1065         }
1066 out:
1067         return r;
1068 }
1069
1070 static struct file_operations kvm_chardev_ops = {
1071         .unlocked_ioctl = kvm_dev_ioctl,
1072         .compat_ioctl   = kvm_dev_ioctl,
1073 };
1074
1075 static struct miscdevice kvm_dev = {
1076         KVM_MINOR,
1077         "kvm",
1078         &kvm_chardev_ops,
1079 };
1080
1081 static void hardware_enable(void *junk)
1082 {
1083         int cpu = raw_smp_processor_id();
1084
1085         if (cpu_isset(cpu, cpus_hardware_enabled))
1086                 return;
1087         cpu_set(cpu, cpus_hardware_enabled);
1088         kvm_arch_hardware_enable(NULL);
1089 }
1090
1091 static void hardware_disable(void *junk)
1092 {
1093         int cpu = raw_smp_processor_id();
1094
1095         if (!cpu_isset(cpu, cpus_hardware_enabled))
1096                 return;
1097         cpu_clear(cpu, cpus_hardware_enabled);
1098         decache_vcpus_on_cpu(cpu);
1099         kvm_arch_hardware_disable(NULL);
1100 }
1101
1102 static int kvm_cpu_hotplug(struct notifier_block *notifier, unsigned long val,
1103                            void *v)
1104 {
1105         int cpu = (long)v;
1106
1107         val &= ~CPU_TASKS_FROZEN;
1108         switch (val) {
1109         case CPU_DYING:
1110                 printk(KERN_INFO "kvm: disabling virtualization on CPU%d\n",
1111                        cpu);
1112                 hardware_disable(NULL);
1113                 break;
1114         case CPU_UP_CANCELED:
1115                 printk(KERN_INFO "kvm: disabling virtualization on CPU%d\n",
1116                        cpu);
1117                 smp_call_function_single(cpu, hardware_disable, NULL, 0, 1);
1118                 break;
1119         case CPU_ONLINE:
1120                 printk(KERN_INFO "kvm: enabling virtualization on CPU%d\n",
1121                        cpu);
1122                 smp_call_function_single(cpu, hardware_enable, NULL, 0, 1);
1123                 break;
1124         }
1125         return NOTIFY_OK;
1126 }
1127
1128 static int kvm_reboot(struct notifier_block *notifier, unsigned long val,
1129                       void *v)
1130 {
1131         if (val == SYS_RESTART) {
1132                 /*
1133                  * Some (well, at least mine) BIOSes hang on reboot if
1134                  * in vmx root mode.
1135                  */
1136                 printk(KERN_INFO "kvm: exiting hardware virtualization\n");
1137                 on_each_cpu(hardware_disable, NULL, 0, 1);
1138         }
1139         return NOTIFY_OK;
1140 }
1141
1142 static struct notifier_block kvm_reboot_notifier = {
1143         .notifier_call = kvm_reboot,
1144         .priority = 0,
1145 };
1146
1147 void kvm_io_bus_init(struct kvm_io_bus *bus)
1148 {
1149         memset(bus, 0, sizeof(*bus));
1150 }
1151
1152 void kvm_io_bus_destroy(struct kvm_io_bus *bus)
1153 {
1154         int i;
1155
1156         for (i = 0; i < bus->dev_count; i++) {
1157                 struct kvm_io_device *pos = bus->devs[i];
1158
1159                 kvm_iodevice_destructor(pos);
1160         }
1161 }
1162
1163 struct kvm_io_device *kvm_io_bus_find_dev(struct kvm_io_bus *bus, gpa_t addr)
1164 {
1165         int i;
1166
1167         for (i = 0; i < bus->dev_count; i++) {
1168                 struct kvm_io_device *pos = bus->devs[i];
1169
1170                 if (pos->in_range(pos, addr))
1171                         return pos;
1172         }
1173
1174         return NULL;
1175 }
1176
1177 void kvm_io_bus_register_dev(struct kvm_io_bus *bus, struct kvm_io_device *dev)
1178 {
1179         BUG_ON(bus->dev_count > (NR_IOBUS_DEVS-1));
1180
1181         bus->devs[bus->dev_count++] = dev;
1182 }
1183
1184 static struct notifier_block kvm_cpu_notifier = {
1185         .notifier_call = kvm_cpu_hotplug,
1186         .priority = 20, /* must be > scheduler priority */
1187 };
1188
1189 static u64 vm_stat_get(void *_offset)
1190 {
1191         unsigned offset = (long)_offset;
1192         u64 total = 0;
1193         struct kvm *kvm;
1194
1195         spin_lock(&kvm_lock);
1196         list_for_each_entry(kvm, &vm_list, vm_list)
1197                 total += *(u32 *)((void *)kvm + offset);
1198         spin_unlock(&kvm_lock);
1199         return total;
1200 }
1201
1202 DEFINE_SIMPLE_ATTRIBUTE(vm_stat_fops, vm_stat_get, NULL, "%llu\n");
1203
1204 static u64 vcpu_stat_get(void *_offset)
1205 {
1206         unsigned offset = (long)_offset;
1207         u64 total = 0;
1208         struct kvm *kvm;
1209         struct kvm_vcpu *vcpu;
1210         int i;
1211
1212         spin_lock(&kvm_lock);
1213         list_for_each_entry(kvm, &vm_list, vm_list)
1214                 for (i = 0; i < KVM_MAX_VCPUS; ++i) {
1215                         vcpu = kvm->vcpus[i];
1216                         if (vcpu)
1217                                 total += *(u32 *)((void *)vcpu + offset);
1218                 }
1219         spin_unlock(&kvm_lock);
1220         return total;
1221 }
1222
1223 DEFINE_SIMPLE_ATTRIBUTE(vcpu_stat_fops, vcpu_stat_get, NULL, "%llu\n");
1224
1225 static struct file_operations *stat_fops[] = {
1226         [KVM_STAT_VCPU] = &vcpu_stat_fops,
1227         [KVM_STAT_VM]   = &vm_stat_fops,
1228 };
1229
1230 static void kvm_init_debug(void)
1231 {
1232         struct kvm_stats_debugfs_item *p;
1233
1234         debugfs_dir = debugfs_create_dir("kvm", NULL);
1235         for (p = debugfs_entries; p->name; ++p)
1236                 p->dentry = debugfs_create_file(p->name, 0444, debugfs_dir,
1237                                                 (void *)(long)p->offset,
1238                                                 stat_fops[p->kind]);
1239 }
1240
1241 static void kvm_exit_debug(void)
1242 {
1243         struct kvm_stats_debugfs_item *p;
1244
1245         for (p = debugfs_entries; p->name; ++p)
1246                 debugfs_remove(p->dentry);
1247         debugfs_remove(debugfs_dir);
1248 }
1249
1250 static int kvm_suspend(struct sys_device *dev, pm_message_t state)
1251 {
1252         hardware_disable(NULL);
1253         return 0;
1254 }
1255
1256 static int kvm_resume(struct sys_device *dev)
1257 {
1258         hardware_enable(NULL);
1259         return 0;
1260 }
1261
1262 static struct sysdev_class kvm_sysdev_class = {
1263         .name = "kvm",
1264         .suspend = kvm_suspend,
1265         .resume = kvm_resume,
1266 };
1267
1268 static struct sys_device kvm_sysdev = {
1269         .id = 0,
1270         .cls = &kvm_sysdev_class,
1271 };
1272
1273 struct page *bad_page;
1274
1275 static inline
1276 struct kvm_vcpu *preempt_notifier_to_vcpu(struct preempt_notifier *pn)
1277 {
1278         return container_of(pn, struct kvm_vcpu, preempt_notifier);
1279 }
1280
1281 static void kvm_sched_in(struct preempt_notifier *pn, int cpu)
1282 {
1283         struct kvm_vcpu *vcpu = preempt_notifier_to_vcpu(pn);
1284
1285         kvm_arch_vcpu_load(vcpu, cpu);
1286 }
1287
1288 static void kvm_sched_out(struct preempt_notifier *pn,
1289                           struct task_struct *next)
1290 {
1291         struct kvm_vcpu *vcpu = preempt_notifier_to_vcpu(pn);
1292
1293         kvm_arch_vcpu_put(vcpu);
1294 }
1295
1296 int kvm_init(void *opaque, unsigned int vcpu_size,
1297                   struct module *module)
1298 {
1299         int r;
1300         int cpu;
1301
1302         kvm_init_debug();
1303
1304         r = kvm_arch_init(opaque);
1305         if (r)
1306                 goto out_fail;
1307
1308         bad_page = alloc_page(GFP_KERNEL | __GFP_ZERO);
1309
1310         if (bad_page == NULL) {
1311                 r = -ENOMEM;
1312                 goto out;
1313         }
1314
1315         r = kvm_arch_hardware_setup();
1316         if (r < 0)
1317                 goto out_free_0;
1318
1319         for_each_online_cpu(cpu) {
1320                 smp_call_function_single(cpu,
1321                                 kvm_arch_check_processor_compat,
1322                                 &r, 0, 1);
1323                 if (r < 0)
1324                         goto out_free_1;
1325         }
1326
1327         on_each_cpu(hardware_enable, NULL, 0, 1);
1328         r = register_cpu_notifier(&kvm_cpu_notifier);
1329         if (r)
1330                 goto out_free_2;
1331         register_reboot_notifier(&kvm_reboot_notifier);
1332
1333         r = sysdev_class_register(&kvm_sysdev_class);
1334         if (r)
1335                 goto out_free_3;
1336
1337         r = sysdev_register(&kvm_sysdev);
1338         if (r)
1339                 goto out_free_4;
1340
1341         /* A kmem cache lets us meet the alignment requirements of fx_save. */
1342         kvm_vcpu_cache = kmem_cache_create("kvm_vcpu", vcpu_size,
1343                                            __alignof__(struct kvm_vcpu),
1344                                            0, NULL);
1345         if (!kvm_vcpu_cache) {
1346                 r = -ENOMEM;
1347                 goto out_free_5;
1348         }
1349
1350         kvm_chardev_ops.owner = module;
1351
1352         r = misc_register(&kvm_dev);
1353         if (r) {
1354                 printk(KERN_ERR "kvm: misc device register failed\n");
1355                 goto out_free;
1356         }
1357
1358         kvm_preempt_ops.sched_in = kvm_sched_in;
1359         kvm_preempt_ops.sched_out = kvm_sched_out;
1360
1361         return 0;
1362
1363 out_free:
1364         kmem_cache_destroy(kvm_vcpu_cache);
1365 out_free_5:
1366         sysdev_unregister(&kvm_sysdev);
1367 out_free_4:
1368         sysdev_class_unregister(&kvm_sysdev_class);
1369 out_free_3:
1370         unregister_reboot_notifier(&kvm_reboot_notifier);
1371         unregister_cpu_notifier(&kvm_cpu_notifier);
1372 out_free_2:
1373         on_each_cpu(hardware_disable, NULL, 0, 1);
1374 out_free_1:
1375         kvm_arch_hardware_unsetup();
1376 out_free_0:
1377         __free_page(bad_page);
1378 out:
1379         kvm_arch_exit();
1380         kvm_exit_debug();
1381 out_fail:
1382         return r;
1383 }
1384 EXPORT_SYMBOL_GPL(kvm_init);
1385
1386 void kvm_exit(void)
1387 {
1388         misc_deregister(&kvm_dev);
1389         kmem_cache_destroy(kvm_vcpu_cache);
1390         sysdev_unregister(&kvm_sysdev);
1391         sysdev_class_unregister(&kvm_sysdev_class);
1392         unregister_reboot_notifier(&kvm_reboot_notifier);
1393         unregister_cpu_notifier(&kvm_cpu_notifier);
1394         on_each_cpu(hardware_disable, NULL, 0, 1);
1395         kvm_arch_hardware_unsetup();
1396         kvm_arch_exit();
1397         kvm_exit_debug();
1398         __free_page(bad_page);
1399 }
1400 EXPORT_SYMBOL_GPL(kvm_exit);