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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  *
   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 void kvm_reload_remote_mmus(struct kvm *kvm)
 123 {
 124         int i, cpu;
 125         cpumask_t cpus;
 126         struct kvm_vcpu *vcpu;
 127
 128         cpus_clear(cpus);
 129         for (i = 0; i < KVM_MAX_VCPUS; ++i) {
 130                 vcpu = kvm->vcpus[i];
 131                 if (!vcpu)
 132                         continue;
 133                 if (test_and_set_bit(KVM_REQ_MMU_RELOAD, &vcpu->requests))
 134                         continue;
 135                 cpu = vcpu->cpu;
 136                 if (cpu != -1 && cpu != raw_smp_processor_id())
 137                         cpu_set(cpu, cpus);
 138         }
 139         if (cpus_empty(cpus))
 140                 return;
 141         smp_call_function_mask(cpus, ack_flush, NULL, 1);
 142 }
 143
 144
 145 int kvm_vcpu_init(struct kvm_vcpu *vcpu, struct kvm *kvm, unsigned id)
 146 {
 147         struct page *page;
 148         int r;
 149
 150         mutex_init(&vcpu->mutex);
 151         vcpu->cpu = -1;
 152         vcpu->kvm = kvm;
 153         vcpu->vcpu_id = id;
 154         init_waitqueue_head(&vcpu->wq);
 155
 156         page = alloc_page(GFP_KERNEL | __GFP_ZERO);
 157         if (!page) {
 158                 r = -ENOMEM;
 159                 goto fail;
 160         }
 161         vcpu->run = page_address(page);
 162
 163         r = kvm_arch_vcpu_init(vcpu);
 164         if (r < 0)
 165                 goto fail_free_run;
 166         return 0;
 167
 168 fail_free_run:
 169         free_page((unsigned long)vcpu->run);
 170 fail:
 171         return r;
 172 }
 173 EXPORT_SYMBOL_GPL(kvm_vcpu_init);
 174
 175 void kvm_vcpu_uninit(struct kvm_vcpu *vcpu)
 176 {
 177         kvm_arch_vcpu_uninit(vcpu);
 178         free_page((unsigned long)vcpu->run);
 179 }
 180 EXPORT_SYMBOL_GPL(kvm_vcpu_uninit);
 181
 182 static struct kvm *kvm_create_vm(void)
 183 {
 184         struct kvm *kvm = kvm_arch_create_vm();
 185
 186         if (IS_ERR(kvm))
 187                 goto out;
 188
 189         kvm->mm = current->mm;
 190         atomic_inc(&kvm->mm->mm_count);
 191         spin_lock_init(&kvm->mmu_lock);
 192         kvm_io_bus_init(&kvm->pio_bus);
 193         mutex_init(&kvm->lock);
 194         kvm_io_bus_init(&kvm->mmio_bus);
 195         init_rwsem(&kvm->slots_lock);
 196         spin_lock(&kvm_lock);
 197         list_add(&kvm->vm_list, &vm_list);
 198         spin_unlock(&kvm_lock);
 199 out:
 200         return kvm;
 201 }
 202
 203 /*
 204  * Free any memory in @free but not in @dont.
 205  */
 206 static void kvm_free_physmem_slot(struct kvm_memory_slot *free,
 207                                   struct kvm_memory_slot *dont)
 208 {
 209         if (!dont || free->rmap != dont->rmap)
 210                 vfree(free->rmap);
 211
 212         if (!dont || free->dirty_bitmap != dont->dirty_bitmap)
 213                 vfree(free->dirty_bitmap);
 214
 215         if (!dont || free->lpage_info != dont->lpage_info)
 216                 vfree(free->lpage_info);
 217
 218         free->npages = 0;
 219         free->dirty_bitmap = NULL;
 220         free->rmap = NULL;
 221         free->lpage_info = NULL;
 222 }
 223
 224 void kvm_free_physmem(struct kvm *kvm)
 225 {
 226         int i;
 227
 228         for (i = 0; i < kvm->nmemslots; ++i)
 229                 kvm_free_physmem_slot(&kvm->memslots[i], NULL);
 230 }
 231
 232 static void kvm_destroy_vm(struct kvm *kvm)
 233 {
 234         struct mm_struct *mm = kvm->mm;
 235
 236         spin_lock(&kvm_lock);
 237         list_del(&kvm->vm_list);
 238         spin_unlock(&kvm_lock);
 239         kvm_io_bus_destroy(&kvm->pio_bus);
 240         kvm_io_bus_destroy(&kvm->mmio_bus);
 241         kvm_arch_destroy_vm(kvm);
 242         mmdrop(mm);
 243 }
 244
 245 static int kvm_vm_release(struct inode *inode, struct file *filp)
 246 {
 247         struct kvm *kvm = filp->private_data;
 248
 249         kvm_destroy_vm(kvm);
 250         return 0;
 251 }
 252
 253 /*
 254  * Allocate some memory and give it an address in the guest physical address
 255  * space.
 256  *
 257  * Discontiguous memory is allowed, mostly for framebuffers.
 258  *
 259  * Must be called holding mmap_sem for write.
 260  */
 261 int __kvm_set_memory_region(struct kvm *kvm,
 262                             struct kvm_userspace_memory_region *mem,
 263                             int user_alloc)
 264 {
 265         int r;
 266         gfn_t base_gfn;
 267         unsigned long npages;
 268         unsigned long i;
 269         struct kvm_memory_slot *memslot;
 270         struct kvm_memory_slot old, new;
 271
 272         r = -EINVAL;
 273         /* General sanity checks */
 274         if (mem->memory_size & (PAGE_SIZE - 1))
 275                 goto out;
 276         if (mem->guest_phys_addr & (PAGE_SIZE - 1))
 277                 goto out;
 278         if (mem->slot >= KVM_MEMORY_SLOTS + KVM_PRIVATE_MEM_SLOTS)
 279                 goto out;
 280         if (mem->guest_phys_addr + mem->memory_size < mem->guest_phys_addr)
 281                 goto out;
 282
 283         memslot = &kvm->memslots[mem->slot];
 284         base_gfn = mem->guest_phys_addr >> PAGE_SHIFT;
 285         npages = mem->memory_size >> PAGE_SHIFT;
 286
 287         if (!npages)
 288                 mem->flags &= ~KVM_MEM_LOG_DIRTY_PAGES;
 289
 290         new = old = *memslot;
 291
 292         new.base_gfn = base_gfn;
 293         new.npages = npages;
 294         new.flags = mem->flags;
 295
 296         /* Disallow changing a memory slot's size. */
 297         r = -EINVAL;
 298         if (npages && old.npages && npages != old.npages)
 299                 goto out_free;
 300
 301         /* Check for overlaps */
 302         r = -EEXIST;
 303         for (i = 0; i < KVM_MEMORY_SLOTS; ++i) {
 304                 struct kvm_memory_slot *s = &kvm->memslots[i];
 305
 306                 if (s == memslot)
 307                         continue;
 308                 if (!((base_gfn + npages <= s->base_gfn) ||
 309                       (base_gfn >= s->base_gfn + s->npages)))
 310                         goto out_free;
 311         }
 312
 313         /* Free page dirty bitmap if unneeded */
 314         if (!(new.flags & KVM_MEM_LOG_DIRTY_PAGES))
 315                 new.dirty_bitmap = NULL;
 316
 317         r = -ENOMEM;
 318
 319         /* Allocate if a slot is being created */
 320         if (npages && !new.rmap) {
 321                 new.rmap = vmalloc(npages * sizeof(struct page *));
 322
 323                 if (!new.rmap)
 324                         goto out_free;
 325
 326                 memset(new.rmap, 0, npages * sizeof(*new.rmap));
 327
 328                 new.user_alloc = user_alloc;
 329                 new.userspace_addr = mem->userspace_addr;
 330         }
 331         if (npages && !new.lpage_info) {
 332                 int largepages = npages / KVM_PAGES_PER_HPAGE;
 333                 if (npages % KVM_PAGES_PER_HPAGE)
 334                         largepages++;
 335                 if (base_gfn % KVM_PAGES_PER_HPAGE)
 336                         largepages++;
 337
 338                 new.lpage_info = vmalloc(largepages * sizeof(*new.lpage_info));
 339
 340                 if (!new.lpage_info)
 341                         goto out_free;
 342
 343                 memset(new.lpage_info, 0, largepages * sizeof(*new.lpage_info));
 344
 345                 if (base_gfn % KVM_PAGES_PER_HPAGE)
 346                         new.lpage_info[0].write_count = 1;
 347                 if ((base_gfn+npages) % KVM_PAGES_PER_HPAGE)
 348                         new.lpage_info[largepages-1].write_count = 1;
 349         }
 350
 351         /* Allocate page dirty bitmap if needed */
 352         if ((new.flags & KVM_MEM_LOG_DIRTY_PAGES) && !new.dirty_bitmap) {
 353                 unsigned dirty_bytes = ALIGN(npages, BITS_PER_LONG) / 8;
 354
 355                 new.dirty_bitmap = vmalloc(dirty_bytes);
 356                 if (!new.dirty_bitmap)
 357                         goto out_free;
 358                 memset(new.dirty_bitmap, 0, dirty_bytes);
 359         }
 360
 361         if (mem->slot >= kvm->nmemslots)
 362                 kvm->nmemslots = mem->slot + 1;
 363
 364         *memslot = new;
 365
 366         r = kvm_arch_set_memory_region(kvm, mem, old, user_alloc);
 367         if (r) {
 368                 *memslot = old;
 369                 goto out_free;
 370         }
 371
 372         kvm_free_physmem_slot(&old, &new);
 373         return 0;
 374
 375 out_free:
 376         kvm_free_physmem_slot(&new, &old);
 377 out:
 378         return r;
 379
 380 }
 381 EXPORT_SYMBOL_GPL(__kvm_set_memory_region);
 382
 383 int kvm_set_memory_region(struct kvm *kvm,
 384                           struct kvm_userspace_memory_region *mem,
 385                           int user_alloc)
 386 {
 387         int r;
 388
 389         down_write(&kvm->slots_lock);
 390         r = __kvm_set_memory_region(kvm, mem, user_alloc);
 391         up_write(&kvm->slots_lock);
 392         return r;
 393 }
 394 EXPORT_SYMBOL_GPL(kvm_set_memory_region);
 395
 396 int kvm_vm_ioctl_set_memory_region(struct kvm *kvm,
 397                                    struct
 398                                    kvm_userspace_memory_region *mem,
 399                                    int user_alloc)
 400 {
 401         if (mem->slot >= KVM_MEMORY_SLOTS)
 402                 return -EINVAL;
 403         return kvm_set_memory_region(kvm, mem, user_alloc);
 404 }
 405
 406 int kvm_get_dirty_log(struct kvm *kvm,
 407                         struct kvm_dirty_log *log, int *is_dirty)
 408 {
 409         struct kvm_memory_slot *memslot;
 410         int r, i;
 411         int n;
 412         unsigned long any = 0;
 413
 414         r = -EINVAL;
 415         if (log->slot >= KVM_MEMORY_SLOTS)
 416                 goto out;
 417
 418         memslot = &kvm->memslots[log->slot];
 419         r = -ENOENT;
 420         if (!memslot->dirty_bitmap)
 421                 goto out;
 422
 423         n = ALIGN(memslot->npages, BITS_PER_LONG) / 8;
 424
 425         for (i = 0; !any && i < n/sizeof(long); ++i)
 426                 any = memslot->dirty_bitmap[i];
 427
 428         r = -EFAULT;
 429         if (copy_to_user(log->dirty_bitmap, memslot->dirty_bitmap, n))
 430                 goto out;
 431
 432         if (any)
 433                 *is_dirty = 1;
 434
 435         r = 0;
 436 out:
 437         return r;
 438 }
 439
 440 int is_error_page(struct page *page)
 441 {
 442         return page == bad_page;
 443 }
 444 EXPORT_SYMBOL_GPL(is_error_page);
 445
 446 static inline unsigned long bad_hva(void)
 447 {
 448         return PAGE_OFFSET;
 449 }
 450
 451 int kvm_is_error_hva(unsigned long addr)
 452 {
 453         return addr == bad_hva();
 454 }
 455 EXPORT_SYMBOL_GPL(kvm_is_error_hva);
 456
 457 static struct kvm_memory_slot *__gfn_to_memslot(struct kvm *kvm, gfn_t gfn)
 458 {
 459         int i;
 460
 461         for (i = 0; i < kvm->nmemslots; ++i) {
 462                 struct kvm_memory_slot *memslot = &kvm->memslots[i];
 463
 464                 if (gfn >= memslot->base_gfn
 465                     && gfn < memslot->base_gfn + memslot->npages)
 466                         return memslot;
 467         }
 468         return NULL;
 469 }
 470
 471 struct kvm_memory_slot *gfn_to_memslot(struct kvm *kvm, gfn_t gfn)
 472 {
 473         gfn = unalias_gfn(kvm, gfn);
 474         return __gfn_to_memslot(kvm, gfn);
 475 }
 476
 477 int kvm_is_visible_gfn(struct kvm *kvm, gfn_t gfn)
 478 {
 479         int i;
 480
 481         gfn = unalias_gfn(kvm, gfn);
 482         for (i = 0; i < KVM_MEMORY_SLOTS; ++i) {
 483                 struct kvm_memory_slot *memslot = &kvm->memslots[i];
 484
 485                 if (gfn >= memslot->base_gfn
 486                     && gfn < memslot->base_gfn + memslot->npages)
 487                         return 1;
 488         }
 489         return 0;
 490 }
 491 EXPORT_SYMBOL_GPL(kvm_is_visible_gfn);
 492
 493 unsigned long gfn_to_hva(struct kvm *kvm, gfn_t gfn)
 494 {
 495         struct kvm_memory_slot *slot;
 496
 497         gfn = unalias_gfn(kvm, gfn);
 498         slot = __gfn_to_memslot(kvm, gfn);
 499         if (!slot)
 500                 return bad_hva();
 501         return (slot->userspace_addr + (gfn - slot->base_gfn) * PAGE_SIZE);
 502 }
 503
 504 /*
 505  * Requires current->mm->mmap_sem to be held
 506  */
 507 struct page *gfn_to_page(struct kvm *kvm, gfn_t gfn)
 508 {
 509         struct page *page[1];
 510         unsigned long addr;
 511         int npages;
 512
 513         might_sleep();
 514
 515         addr = gfn_to_hva(kvm, gfn);
 516         if (kvm_is_error_hva(addr)) {
 517                 get_page(bad_page);
 518                 return bad_page;
 519         }
 520
 521         npages = get_user_pages(current, current->mm, addr, 1, 1, 1, page,
 522                                 NULL);
 523
 524         if (npages != 1) {
 525                 get_page(bad_page);
 526                 return bad_page;
 527         }
 528
 529         return page[0];
 530 }
 531
 532 EXPORT_SYMBOL_GPL(gfn_to_page);
 533
 534 void kvm_release_page_clean(struct page *page)
 535 {
 536         put_page(page);
 537 }
 538 EXPORT_SYMBOL_GPL(kvm_release_page_clean);
 539
 540 void kvm_release_page_dirty(struct page *page)
 541 {
 542         if (!PageReserved(page))
 543                 SetPageDirty(page);
 544         put_page(page);
 545 }
 546 EXPORT_SYMBOL_GPL(kvm_release_page_dirty);
 547
 548 static int next_segment(unsigned long len, int offset)
 549 {
 550         if (len > PAGE_SIZE - offset)
 551                 return PAGE_SIZE - offset;
 552         else
 553                 return len;
 554 }
 555
 556 int kvm_read_guest_page(struct kvm *kvm, gfn_t gfn, void *data, int offset,
 557                         int len)
 558 {
 559         int r;
 560         unsigned long addr;
 561
 562         addr = gfn_to_hva(kvm, gfn);
 563         if (kvm_is_error_hva(addr))
 564                 return -EFAULT;
 565         r = copy_from_user(data, (void __user *)addr + offset, len);
 566         if (r)
 567                 return -EFAULT;
 568         return 0;
 569 }
 570 EXPORT_SYMBOL_GPL(kvm_read_guest_page);
 571
 572 int kvm_read_guest(struct kvm *kvm, gpa_t gpa, void *data, unsigned long len)
 573 {
 574         gfn_t gfn = gpa >> PAGE_SHIFT;
 575         int seg;
 576         int offset = offset_in_page(gpa);
 577         int ret;
 578
 579         while ((seg = next_segment(len, offset)) != 0) {
 580                 ret = kvm_read_guest_page(kvm, gfn, data, offset, seg);
 581                 if (ret < 0)
 582                         return ret;
 583                 offset = 0;
 584                 len -= seg;
 585                 data += seg;
 586                 ++gfn;
 587         }
 588         return 0;
 589 }
 590 EXPORT_SYMBOL_GPL(kvm_read_guest);
 591
 592 int kvm_read_guest_atomic(struct kvm *kvm, gpa_t gpa, void *data,
 593                           unsigned long len)
 594 {
 595         int r;
 596         unsigned long addr;
 597         gfn_t gfn = gpa >> PAGE_SHIFT;
 598         int offset = offset_in_page(gpa);
 599
 600         addr = gfn_to_hva(kvm, gfn);
 601         if (kvm_is_error_hva(addr))
 602                 return -EFAULT;
 603         pagefault_disable();
 604         r = __copy_from_user_inatomic(data, (void __user *)addr + offset, len);
 605         pagefault_enable();
 606         if (r)
 607                 return -EFAULT;
 608         return 0;
 609 }
 610 EXPORT_SYMBOL(kvm_read_guest_atomic);
 611
 612 int kvm_write_guest_page(struct kvm *kvm, gfn_t gfn, const void *data,
 613                          int offset, int len)
 614 {
 615         int r;
 616         unsigned long addr;
 617
 618         addr = gfn_to_hva(kvm, gfn);
 619         if (kvm_is_error_hva(addr))
 620                 return -EFAULT;
 621         r = copy_to_user((void __user *)addr + offset, data, len);
 622         if (r)
 623                 return -EFAULT;
 624         mark_page_dirty(kvm, gfn);
 625         return 0;
 626 }
 627 EXPORT_SYMBOL_GPL(kvm_write_guest_page);
 628
 629 int kvm_write_guest(struct kvm *kvm, gpa_t gpa, const void *data,
 630                     unsigned long len)
 631 {
 632         gfn_t gfn = gpa >> PAGE_SHIFT;
 633         int seg;
 634         int offset = offset_in_page(gpa);
 635         int ret;
 636
 637         while ((seg = next_segment(len, offset)) != 0) {
 638                 ret = kvm_write_guest_page(kvm, gfn, data, offset, seg);
 639                 if (ret < 0)
 640                         return ret;
 641                 offset = 0;
 642                 len -= seg;
 643                 data += seg;
 644                 ++gfn;
 645         }
 646         return 0;
 647 }
 648
 649 int kvm_clear_guest_page(struct kvm *kvm, gfn_t gfn, int offset, int len)
 650 {
 651         return kvm_write_guest_page(kvm, gfn, empty_zero_page, offset, len);
 652 }
 653 EXPORT_SYMBOL_GPL(kvm_clear_guest_page);
 654
 655 int kvm_clear_guest(struct kvm *kvm, gpa_t gpa, unsigned long len)
 656 {
 657         gfn_t gfn = gpa >> PAGE_SHIFT;
 658         int seg;
 659         int offset = offset_in_page(gpa);
 660         int ret;
 661
 662         while ((seg = next_segment(len, offset)) != 0) {
 663                 ret = kvm_clear_guest_page(kvm, gfn, offset, seg);
 664                 if (ret < 0)
 665                         return ret;
 666                 offset = 0;
 667                 len -= seg;
 668                 ++gfn;
 669         }
 670         return 0;
 671 }
 672 EXPORT_SYMBOL_GPL(kvm_clear_guest);
 673
 674 void mark_page_dirty(struct kvm *kvm, gfn_t gfn)
 675 {
 676         struct kvm_memory_slot *memslot;
 677
 678         gfn = unalias_gfn(kvm, gfn);
 679         memslot = __gfn_to_memslot(kvm, gfn);
 680         if (memslot && memslot->dirty_bitmap) {
 681                 unsigned long rel_gfn = gfn - memslot->base_gfn;
 682
 683                 /* avoid RMW */
 684                 if (!test_bit(rel_gfn, memslot->dirty_bitmap))
 685                         set_bit(rel_gfn, memslot->dirty_bitmap);
 686         }
 687 }
 688
 689 /*
 690  * The vCPU has executed a HLT instruction with in-kernel mode enabled.
 691  */
 692 void kvm_vcpu_block(struct kvm_vcpu *vcpu)
 693 {
 694         DECLARE_WAITQUEUE(wait, current);
 695
 696         add_wait_queue(&vcpu->wq, &wait);
 697
 698         /*
 699          * We will block until either an interrupt or a signal wakes us up
 700          */
 701         while (!kvm_cpu_has_interrupt(vcpu)
 702                && !signal_pending(current)
 703                && !kvm_arch_vcpu_runnable(vcpu)) {
 704                 set_current_state(TASK_INTERRUPTIBLE);
 705                 vcpu_put(vcpu);
 706                 schedule();
 707                 vcpu_load(vcpu);
 708         }
 709
 710         __set_current_state(TASK_RUNNING);
 711         remove_wait_queue(&vcpu->wq, &wait);
 712 }
 713
 714 void kvm_resched(struct kvm_vcpu *vcpu)
 715 {
 716         if (!need_resched())
 717                 return;
 718         cond_resched();
 719 }
 720 EXPORT_SYMBOL_GPL(kvm_resched);
 721
 722 static int kvm_vcpu_fault(struct vm_area_struct *vma, struct vm_fault *vmf)
 723 {
 724         struct kvm_vcpu *vcpu = vma->vm_file->private_data;
 725         struct page *page;
 726
 727         if (vmf->pgoff == 0)
 728                 page = virt_to_page(vcpu->run);
 729 #ifdef CONFIG_X86
 730         else if (vmf->pgoff == KVM_PIO_PAGE_OFFSET)
 731                 page = virt_to_page(vcpu->arch.pio_data);
 732 #endif
 733         else
 734                 return VM_FAULT_SIGBUS;
 735         get_page(page);
 736         vmf->page = page;
 737         return 0;
 738 }
 739
 740 static struct vm_operations_struct kvm_vcpu_vm_ops = {
 741         .fault = kvm_vcpu_fault,
 742 };
 743
 744 static int kvm_vcpu_mmap(struct file *file, struct vm_area_struct *vma)
 745 {
 746         vma->vm_ops = &kvm_vcpu_vm_ops;
 747         return 0;
 748 }
 749
 750 static int kvm_vcpu_release(struct inode *inode, struct file *filp)
 751 {
 752         struct kvm_vcpu *vcpu = filp->private_data;
 753
 754         fput(vcpu->kvm->filp);
 755         return 0;
 756 }
 757
 758 static const struct file_operations kvm_vcpu_fops = {
 759         .release        = kvm_vcpu_release,
 760         .unlocked_ioctl = kvm_vcpu_ioctl,
 761         .compat_ioctl   = kvm_vcpu_ioctl,
 762         .mmap           = kvm_vcpu_mmap,
 763 };
 764
 765 /*
 766  * Allocates an inode for the vcpu.
 767  */
 768 static int create_vcpu_fd(struct kvm_vcpu *vcpu)
 769 {
 770         int fd, r;
 771         struct inode *inode;
 772         struct file *file;
 773
 774         r = anon_inode_getfd(&fd, &inode, &file,
 775                              "kvm-vcpu", &kvm_vcpu_fops, vcpu);
 776         if (r)
 777                 return r;
 778         atomic_inc(&vcpu->kvm->filp->f_count);
 779         return fd;
 780 }
 781
 782 /*
 783  * Creates some virtual cpus.  Good luck creating more than one.
 784  */
 785 static int kvm_vm_ioctl_create_vcpu(struct kvm *kvm, int n)
 786 {
 787         int r;
 788         struct kvm_vcpu *vcpu;
 789
 790         if (!valid_vcpu(n))
 791                 return -EINVAL;
 792
 793         vcpu = kvm_arch_vcpu_create(kvm, n);
 794         if (IS_ERR(vcpu))
 795                 return PTR_ERR(vcpu);
 796
 797         preempt_notifier_init(&vcpu->preempt_notifier, &kvm_preempt_ops);
 798
 799         r = kvm_arch_vcpu_setup(vcpu);
 800         if (r)
 801                 goto vcpu_destroy;
 802
 803         mutex_lock(&kvm->lock);
 804         if (kvm->vcpus[n]) {
 805                 r = -EEXIST;
 806                 mutex_unlock(&kvm->lock);
 807                 goto vcpu_destroy;
 808         }
 809         kvm->vcpus[n] = vcpu;
 810         mutex_unlock(&kvm->lock);
 811
 812         /* Now it's all set up, let userspace reach it */
 813         r = create_vcpu_fd(vcpu);
 814         if (r < 0)
 815                 goto unlink;
 816         return r;
 817
 818 unlink:
 819         mutex_lock(&kvm->lock);
 820         kvm->vcpus[n] = NULL;
 821         mutex_unlock(&kvm->lock);
 822 vcpu_destroy:
 823         kvm_arch_vcpu_destroy(vcpu);
 824         return r;
 825 }
 826
 827 static int kvm_vcpu_ioctl_set_sigmask(struct kvm_vcpu *vcpu, sigset_t *sigset)
 828 {
 829         if (sigset) {
 830                 sigdelsetmask(sigset, sigmask(SIGKILL)|sigmask(SIGSTOP));
 831                 vcpu->sigset_active = 1;
 832                 vcpu->sigset = *sigset;
 833         } else
 834                 vcpu->sigset_active = 0;
 835         return 0;
 836 }
 837
 838 static long kvm_vcpu_ioctl(struct file *filp,
 839                            unsigned int ioctl, unsigned long arg)
 840 {
 841         struct kvm_vcpu *vcpu = filp->private_data;
 842         void __user *argp = (void __user *)arg;
 843         int r;
 844
 845         if (vcpu->kvm->mm != current->mm)
 846                 return -EIO;
 847         switch (ioctl) {
 848         case KVM_RUN:
 849                 r = -EINVAL;
 850                 if (arg)
 851                         goto out;
 852                 r = kvm_arch_vcpu_ioctl_run(vcpu, vcpu->run);
 853                 break;
 854         case KVM_GET_REGS: {
 855                 struct kvm_regs kvm_regs;
 856
 857                 memset(&kvm_regs, 0, sizeof kvm_regs);
 858                 r = kvm_arch_vcpu_ioctl_get_regs(vcpu, &kvm_regs);
 859                 if (r)
 860                         goto out;
 861                 r = -EFAULT;
 862                 if (copy_to_user(argp, &kvm_regs, sizeof kvm_regs))
 863                         goto out;
 864                 r = 0;
 865                 break;
 866         }
 867         case KVM_SET_REGS: {
 868                 struct kvm_regs kvm_regs;
 869
 870                 r = -EFAULT;
 871                 if (copy_from_user(&kvm_regs, argp, sizeof kvm_regs))
 872                         goto out;
 873                 r = kvm_arch_vcpu_ioctl_set_regs(vcpu, &kvm_regs);
 874                 if (r)
 875                         goto out;
 876                 r = 0;
 877                 break;
 878         }
 879         case KVM_GET_SREGS: {
 880                 struct kvm_sregs kvm_sregs;
 881
 882                 memset(&kvm_sregs, 0, sizeof kvm_sregs);
 883                 r = kvm_arch_vcpu_ioctl_get_sregs(vcpu, &kvm_sregs);
 884                 if (r)
 885                         goto out;
 886                 r = -EFAULT;
 887                 if (copy_to_user(argp, &kvm_sregs, sizeof kvm_sregs))
 888                         goto out;
 889                 r = 0;
 890                 break;
 891         }
 892         case KVM_SET_SREGS: {
 893                 struct kvm_sregs kvm_sregs;
 894
 895                 r = -EFAULT;
 896                 if (copy_from_user(&kvm_sregs, argp, sizeof kvm_sregs))
 897                         goto out;
 898                 r = kvm_arch_vcpu_ioctl_set_sregs(vcpu, &kvm_sregs);
 899                 if (r)
 900                         goto out;
 901                 r = 0;
 902                 break;
 903         }
 904         case KVM_TRANSLATE: {
 905                 struct kvm_translation tr;
 906
 907                 r = -EFAULT;
 908                 if (copy_from_user(&tr, argp, sizeof tr))
 909                         goto out;
 910                 r = kvm_arch_vcpu_ioctl_translate(vcpu, &tr);
 911                 if (r)
 912                         goto out;
 913                 r = -EFAULT;
 914                 if (copy_to_user(argp, &tr, sizeof tr))
 915                         goto out;
 916                 r = 0;
 917                 break;
 918         }
 919         case KVM_DEBUG_GUEST: {
 920                 struct kvm_debug_guest dbg;
 921
 922                 r = -EFAULT;
 923                 if (copy_from_user(&dbg, argp, sizeof dbg))
 924                         goto out;
 925                 r = kvm_arch_vcpu_ioctl_debug_guest(vcpu, &dbg);
 926                 if (r)
 927                         goto out;
 928                 r = 0;
 929                 break;
 930         }
 931         case KVM_SET_SIGNAL_MASK: {
 932                 struct kvm_signal_mask __user *sigmask_arg = argp;
 933                 struct kvm_signal_mask kvm_sigmask;
 934                 sigset_t sigset, *p;
 935
 936                 p = NULL;
 937                 if (argp) {
 938                         r = -EFAULT;
 939                         if (copy_from_user(&kvm_sigmask, argp,
 940                                            sizeof kvm_sigmask))
 941                                 goto out;
 942                         r = -EINVAL;
 943                         if (kvm_sigmask.len != sizeof sigset)
 944                                 goto out;
 945                         r = -EFAULT;
 946                         if (copy_from_user(&sigset, sigmask_arg->sigset,
 947                                            sizeof sigset))
 948                                 goto out;
 949                         p = &sigset;
 950                 }
 951                 r = kvm_vcpu_ioctl_set_sigmask(vcpu, &sigset);
 952                 break;
 953         }
 954         case KVM_GET_FPU: {
 955                 struct kvm_fpu fpu;
 956
 957                 memset(&fpu, 0, sizeof fpu);
 958                 r = kvm_arch_vcpu_ioctl_get_fpu(vcpu, &fpu);
 959                 if (r)
 960                         goto out;
 961                 r = -EFAULT;
 962                 if (copy_to_user(argp, &fpu, sizeof fpu))
 963                         goto out;
 964                 r = 0;
 965                 break;
 966         }
 967         case KVM_SET_FPU: {
 968                 struct kvm_fpu fpu;
 969
 970                 r = -EFAULT;
 971                 if (copy_from_user(&fpu, argp, sizeof fpu))
 972                         goto out;
 973                 r = kvm_arch_vcpu_ioctl_set_fpu(vcpu, &fpu);
 974                 if (r)
 975                         goto out;
 976                 r = 0;
 977                 break;
 978         }
 979         default:
 980                 r = kvm_arch_vcpu_ioctl(filp, ioctl, arg);
 981         }
 982 out:
 983         return r;
 984 }
 985
 986 static long kvm_vm_ioctl(struct file *filp,
 987                            unsigned int ioctl, unsigned long arg)
 988 {
 989         struct kvm *kvm = filp->private_data;
 990         void __user *argp = (void __user *)arg;
 991         int r;
 992
 993         if (kvm->mm != current->mm)
 994                 return -EIO;
 995         switch (ioctl) {
 996         case KVM_CREATE_VCPU:
 997                 r = kvm_vm_ioctl_create_vcpu(kvm, arg);
 998                 if (r < 0)
 999                         goto out;
1000                 break;
1001         case KVM_SET_USER_MEMORY_REGION: {
1002                 struct kvm_userspace_memory_region kvm_userspace_mem;
1003
1004                 r = -EFAULT;
1005                 if (copy_from_user(&kvm_userspace_mem, argp,
1006                                                 sizeof kvm_userspace_mem))
1007                         goto out;
1008
1009                 r = kvm_vm_ioctl_set_memory_region(kvm, &kvm_userspace_mem, 1);
1010                 if (r)
1011                         goto out;
1012                 break;
1013         }
1014         case KVM_GET_DIRTY_LOG: {
1015                 struct kvm_dirty_log log;
1016
1017                 r = -EFAULT;
1018                 if (copy_from_user(&log, argp, sizeof log))
1019                         goto out;
1020                 r = kvm_vm_ioctl_get_dirty_log(kvm, &log);
1021                 if (r)
1022                         goto out;
1023                 break;
1024         }
1025         default:
1026                 r = kvm_arch_vm_ioctl(filp, ioctl, arg);
1027         }
1028 out:
1029         return r;
1030 }
1031
1032 static int kvm_vm_fault(struct vm_area_struct *vma, struct vm_fault *vmf)
1033 {
1034         struct kvm *kvm = vma->vm_file->private_data;
1035         struct page *page;
1036
1037         if (!kvm_is_visible_gfn(kvm, vmf->pgoff))
1038                 return VM_FAULT_SIGBUS;
1039         page = gfn_to_page(kvm, vmf->pgoff);
1040         if (is_error_page(page)) {
1041                 kvm_release_page_clean(page);
1042                 return VM_FAULT_SIGBUS;
1043         }
1044         vmf->page = page;
1045         return 0;
1046 }
1047
1048 static struct vm_operations_struct kvm_vm_vm_ops = {
1049         .fault = kvm_vm_fault,
1050 };
1051
1052 static int kvm_vm_mmap(struct file *file, struct vm_area_struct *vma)
1053 {
1054         vma->vm_ops = &kvm_vm_vm_ops;
1055         return 0;
1056 }
1057
1058 static const struct file_operations kvm_vm_fops = {
1059         .release        = kvm_vm_release,
1060         .unlocked_ioctl = kvm_vm_ioctl,
1061         .compat_ioctl   = kvm_vm_ioctl,
1062         .mmap           = kvm_vm_mmap,
1063 };
1064
1065 static int kvm_dev_ioctl_create_vm(void)
1066 {
1067         int fd, r;
1068         struct inode *inode;
1069         struct file *file;
1070         struct kvm *kvm;
1071
1072         kvm = kvm_create_vm();
1073         if (IS_ERR(kvm))
1074                 return PTR_ERR(kvm);
1075         r = anon_inode_getfd(&fd, &inode, &file, "kvm-vm", &kvm_vm_fops, kvm);
1076         if (r) {
1077                 kvm_destroy_vm(kvm);
1078                 return r;
1079         }
1080
1081         kvm->filp = file;
1082
1083         return fd;
1084 }
1085
1086 static long kvm_dev_ioctl(struct file *filp,
1087                           unsigned int ioctl, unsigned long arg)
1088 {
1089         void __user *argp = (void __user *)arg;
1090         long r = -EINVAL;
1091
1092         switch (ioctl) {
1093         case KVM_GET_API_VERSION:
1094                 r = -EINVAL;
1095                 if (arg)
1096                         goto out;
1097                 r = KVM_API_VERSION;
1098                 break;
1099         case KVM_CREATE_VM:
1100                 r = -EINVAL;
1101                 if (arg)
1102                         goto out;
1103                 r = kvm_dev_ioctl_create_vm();
1104                 break;
1105         case KVM_CHECK_EXTENSION:
1106                 r = kvm_dev_ioctl_check_extension((long)argp);
1107                 break;
1108         case KVM_GET_VCPU_MMAP_SIZE:
1109                 r = -EINVAL;
1110                 if (arg)
1111                         goto out;
1112                 r = PAGE_SIZE;     /* struct kvm_run */
1113 #ifdef CONFIG_X86
1114                 r += PAGE_SIZE;    /* pio data page */
1115 #endif
1116                 break;
1117         default:
1118                 return kvm_arch_dev_ioctl(filp, ioctl, arg);
1119         }
1120 out:
1121         return r;
1122 }
1123
1124 static struct file_operations kvm_chardev_ops = {
1125         .unlocked_ioctl = kvm_dev_ioctl,
1126         .compat_ioctl   = kvm_dev_ioctl,
1127 };
1128
1129 static struct miscdevice kvm_dev = {
1130         KVM_MINOR,
1131         "kvm",
1132         &kvm_chardev_ops,
1133 };
1134
1135 static void hardware_enable(void *junk)
1136 {
1137         int cpu = raw_smp_processor_id();
1138
1139         if (cpu_isset(cpu, cpus_hardware_enabled))
1140                 return;
1141         cpu_set(cpu, cpus_hardware_enabled);
1142         kvm_arch_hardware_enable(NULL);
1143 }
1144
1145 static void hardware_disable(void *junk)
1146 {
1147         int cpu = raw_smp_processor_id();
1148
1149         if (!cpu_isset(cpu, cpus_hardware_enabled))
1150                 return;
1151         cpu_clear(cpu, cpus_hardware_enabled);
1152         decache_vcpus_on_cpu(cpu);
1153         kvm_arch_hardware_disable(NULL);
1154 }
1155
1156 static int kvm_cpu_hotplug(struct notifier_block *notifier, unsigned long val,
1157                            void *v)
1158 {
1159         int cpu = (long)v;
1160
1161         val &= ~CPU_TASKS_FROZEN;
1162         switch (val) {
1163         case CPU_DYING:
1164                 printk(KERN_INFO "kvm: disabling virtualization on CPU%d\n",
1165                        cpu);
1166                 hardware_disable(NULL);
1167                 break;
1168         case CPU_UP_CANCELED:
1169                 printk(KERN_INFO "kvm: disabling virtualization on CPU%d\n",
1170                        cpu);
1171                 smp_call_function_single(cpu, hardware_disable, NULL, 0, 1);
1172                 break;
1173         case CPU_ONLINE:
1174                 printk(KERN_INFO "kvm: enabling virtualization on CPU%d\n",
1175                        cpu);
1176                 smp_call_function_single(cpu, hardware_enable, NULL, 0, 1);
1177                 break;
1178         }
1179         return NOTIFY_OK;
1180 }
1181
1182 static int kvm_reboot(struct notifier_block *notifier, unsigned long val,
1183                       void *v)
1184 {
1185         if (val == SYS_RESTART) {
1186                 /*
1187                  * Some (well, at least mine) BIOSes hang on reboot if
1188                  * in vmx root mode.
1189                  */
1190                 printk(KERN_INFO "kvm: exiting hardware virtualization\n");
1191                 on_each_cpu(hardware_disable, NULL, 0, 1);
1192         }
1193         return NOTIFY_OK;
1194 }
1195
1196 static struct notifier_block kvm_reboot_notifier = {
1197         .notifier_call = kvm_reboot,
1198         .priority = 0,
1199 };
1200
1201 void kvm_io_bus_init(struct kvm_io_bus *bus)
1202 {
1203         memset(bus, 0, sizeof(*bus));
1204 }
1205
1206 void kvm_io_bus_destroy(struct kvm_io_bus *bus)
1207 {
1208         int i;
1209
1210         for (i = 0; i < bus->dev_count; i++) {
1211                 struct kvm_io_device *pos = bus->devs[i];
1212
1213                 kvm_iodevice_destructor(pos);
1214         }
1215 }
1216
1217 struct kvm_io_device *kvm_io_bus_find_dev(struct kvm_io_bus *bus, gpa_t addr)
1218 {
1219         int i;
1220
1221         for (i = 0; i < bus->dev_count; i++) {
1222                 struct kvm_io_device *pos = bus->devs[i];
1223
1224                 if (pos->in_range(pos, addr))
1225                         return pos;
1226         }
1227
1228         return NULL;
1229 }
1230
1231 void kvm_io_bus_register_dev(struct kvm_io_bus *bus, struct kvm_io_device *dev)
1232 {
1233         BUG_ON(bus->dev_count > (NR_IOBUS_DEVS-1));
1234
1235         bus->devs[bus->dev_count++] = dev;
1236 }
1237
1238 static struct notifier_block kvm_cpu_notifier = {
1239         .notifier_call = kvm_cpu_hotplug,
1240         .priority = 20, /* must be > scheduler priority */
1241 };
1242
1243 static int vm_stat_get(void *_offset, u64 *val)
1244 {
1245         unsigned offset = (long)_offset;
1246         struct kvm *kvm;
1247
1248         *val = 0;
1249         spin_lock(&kvm_lock);
1250         list_for_each_entry(kvm, &vm_list, vm_list)
1251                 *val += *(u32 *)((void *)kvm + offset);
1252         spin_unlock(&kvm_lock);
1253         return 0;
1254 }
1255
1256 DEFINE_SIMPLE_ATTRIBUTE(vm_stat_fops, vm_stat_get, NULL, "%llu\n");
1257
1258 static int vcpu_stat_get(void *_offset, u64 *val)
1259 {
1260         unsigned offset = (long)_offset;
1261         struct kvm *kvm;
1262         struct kvm_vcpu *vcpu;
1263         int i;
1264
1265         *val = 0;
1266         spin_lock(&kvm_lock);
1267         list_for_each_entry(kvm, &vm_list, vm_list)
1268                 for (i = 0; i < KVM_MAX_VCPUS; ++i) {
1269                         vcpu = kvm->vcpus[i];
1270                         if (vcpu)
1271                                 *val += *(u32 *)((void *)vcpu + offset);
1272                 }
1273         spin_unlock(&kvm_lock);
1274         return 0;
1275 }
1276
1277 DEFINE_SIMPLE_ATTRIBUTE(vcpu_stat_fops, vcpu_stat_get, NULL, "%llu\n");
1278
1279 static struct file_operations *stat_fops[] = {
1280         [KVM_STAT_VCPU] = &vcpu_stat_fops,
1281         [KVM_STAT_VM]   = &vm_stat_fops,
1282 };
1283
1284 static void kvm_init_debug(void)
1285 {
1286         struct kvm_stats_debugfs_item *p;
1287
1288         debugfs_dir = debugfs_create_dir("kvm", NULL);
1289         for (p = debugfs_entries; p->name; ++p)
1290                 p->dentry = debugfs_create_file(p->name, 0444, debugfs_dir,
1291                                                 (void *)(long)p->offset,
1292                                                 stat_fops[p->kind]);
1293 }
1294
1295 static void kvm_exit_debug(void)
1296 {
1297         struct kvm_stats_debugfs_item *p;
1298
1299         for (p = debugfs_entries; p->name; ++p)
1300                 debugfs_remove(p->dentry);
1301         debugfs_remove(debugfs_dir);
1302 }
1303
1304 static int kvm_suspend(struct sys_device *dev, pm_message_t state)
1305 {
1306         hardware_disable(NULL);
1307         return 0;
1308 }
1309
1310 static int kvm_resume(struct sys_device *dev)
1311 {
1312         hardware_enable(NULL);
1313         return 0;
1314 }
1315
1316 static struct sysdev_class kvm_sysdev_class = {
1317         .name = "kvm",
1318         .suspend = kvm_suspend,
1319         .resume = kvm_resume,
1320 };
1321
1322 static struct sys_device kvm_sysdev = {
1323         .id = 0,
1324         .cls = &kvm_sysdev_class,
1325 };
1326
1327 struct page *bad_page;
1328
1329 static inline
1330 struct kvm_vcpu *preempt_notifier_to_vcpu(struct preempt_notifier *pn)
1331 {
1332         return container_of(pn, struct kvm_vcpu, preempt_notifier);
1333 }
1334
1335 static void kvm_sched_in(struct preempt_notifier *pn, int cpu)
1336 {
1337         struct kvm_vcpu *vcpu = preempt_notifier_to_vcpu(pn);
1338
1339         kvm_arch_vcpu_load(vcpu, cpu);
1340 }
1341
1342 static void kvm_sched_out(struct preempt_notifier *pn,
1343                           struct task_struct *next)
1344 {
1345         struct kvm_vcpu *vcpu = preempt_notifier_to_vcpu(pn);
1346
1347         kvm_arch_vcpu_put(vcpu);
1348 }
1349
1350 int kvm_init(void *opaque, unsigned int vcpu_size,
1351                   struct module *module)
1352 {
1353         int r;
1354         int cpu;
1355
1356         kvm_init_debug();
1357
1358         r = kvm_arch_init(opaque);
1359         if (r)
1360                 goto out_fail;
1361
1362         bad_page = alloc_page(GFP_KERNEL | __GFP_ZERO);
1363
1364         if (bad_page == NULL) {
1365                 r = -ENOMEM;
1366                 goto out;
1367         }
1368
1369         r = kvm_arch_hardware_setup();
1370         if (r < 0)
1371                 goto out_free_0;
1372
1373         for_each_online_cpu(cpu) {
1374                 smp_call_function_single(cpu,
1375                                 kvm_arch_check_processor_compat,
1376                                 &r, 0, 1);
1377                 if (r < 0)
1378                         goto out_free_1;
1379         }
1380
1381         on_each_cpu(hardware_enable, NULL, 0, 1);
1382         r = register_cpu_notifier(&kvm_cpu_notifier);
1383         if (r)
1384                 goto out_free_2;
1385         register_reboot_notifier(&kvm_reboot_notifier);
1386
1387         r = sysdev_class_register(&kvm_sysdev_class);
1388         if (r)
1389                 goto out_free_3;
1390
1391         r = sysdev_register(&kvm_sysdev);
1392         if (r)
1393                 goto out_free_4;
1394
1395         /* A kmem cache lets us meet the alignment requirements of fx_save. */
1396         kvm_vcpu_cache = kmem_cache_create("kvm_vcpu", vcpu_size,
1397                                            __alignof__(struct kvm_vcpu),
1398                                            0, NULL);
1399         if (!kvm_vcpu_cache) {
1400                 r = -ENOMEM;
1401                 goto out_free_5;
1402         }
1403
1404         kvm_chardev_ops.owner = module;
1405
1406         r = misc_register(&kvm_dev);
1407         if (r) {
1408                 printk(KERN_ERR "kvm: misc device register failed\n");
1409                 goto out_free;
1410         }
1411
1412         kvm_preempt_ops.sched_in = kvm_sched_in;
1413         kvm_preempt_ops.sched_out = kvm_sched_out;
1414
1415         return 0;
1416
1417 out_free:
1418         kmem_cache_destroy(kvm_vcpu_cache);
1419 out_free_5:
1420         sysdev_unregister(&kvm_sysdev);
1421 out_free_4:
1422         sysdev_class_unregister(&kvm_sysdev_class);
1423 out_free_3:
1424         unregister_reboot_notifier(&kvm_reboot_notifier);
1425         unregister_cpu_notifier(&kvm_cpu_notifier);
1426 out_free_2:
1427         on_each_cpu(hardware_disable, NULL, 0, 1);
1428 out_free_1:
1429         kvm_arch_hardware_unsetup();
1430 out_free_0:
1431         __free_page(bad_page);
1432 out:
1433         kvm_arch_exit();
1434         kvm_exit_debug();
1435 out_fail:
1436         return r;
1437 }
1438 EXPORT_SYMBOL_GPL(kvm_init);
1439
1440 void kvm_exit(void)
1441 {
1442         misc_deregister(&kvm_dev);
1443         kmem_cache_destroy(kvm_vcpu_cache);
1444         sysdev_unregister(&kvm_sysdev);
1445         sysdev_class_unregister(&kvm_sysdev_class);
1446         unregister_reboot_notifier(&kvm_reboot_notifier);
1447         unregister_cpu_notifier(&kvm_cpu_notifier);
1448         on_each_cpu(hardware_disable, NULL, 0, 1);
1449         kvm_arch_hardware_unsetup();
1450         kvm_arch_exit();
1451         kvm_exit_debug();
1452         __free_page(bad_page);
1453 }
1454 EXPORT_SYMBOL_GPL(kvm_exit);