git.oblomov.eu Git - linux-2.6/blob - 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 #include <linux/swap.h>
  44
  45 #include <asm/processor.h>
  46 #include <asm/io.h>
  47 #include <asm/uaccess.h>
  48 #include <asm/pgtable.h>
  49
  50 #ifdef KVM_COALESCED_MMIO_PAGE_OFFSET
  51 #include "coalesced_mmio.h"
  52 #endif
  53
  54 #ifdef KVM_CAP_DEVICE_ASSIGNMENT
  55 #include <linux/pci.h>
  56 #include <linux/interrupt.h>
  57 #include "irq.h"
  58 #endif
  59
  60 MODULE_AUTHOR("Qumranet");
  61 MODULE_LICENSE("GPL");
  62
  63 static int msi2intx = 1;
  64 module_param(msi2intx, bool, 0);
  65
  66 DEFINE_SPINLOCK(kvm_lock);
  67 LIST_HEAD(vm_list);
  68
  69 static cpumask_var_t cpus_hardware_enabled;
  70
  71 struct kmem_cache *kvm_vcpu_cache;
  72 EXPORT_SYMBOL_GPL(kvm_vcpu_cache);
  73
  74 static __read_mostly struct preempt_ops kvm_preempt_ops;
  75
  76 struct dentry *kvm_debugfs_dir;
  77
  78 static long kvm_vcpu_ioctl(struct file *file, unsigned int ioctl,
  79                            unsigned long arg);
  80
  81 static bool kvm_rebooting;
  82
  83 #ifdef KVM_CAP_DEVICE_ASSIGNMENT
  84 static struct kvm_assigned_dev_kernel *kvm_find_assigned_dev(struct list_head *head,
  85                                                       int assigned_dev_id)
  86 {
  87         struct list_head *ptr;
  88         struct kvm_assigned_dev_kernel *match;
  89
  90         list_for_each(ptr, head) {
  91                 match = list_entry(ptr, struct kvm_assigned_dev_kernel, list);
  92                 if (match->assigned_dev_id == assigned_dev_id)
  93                         return match;
  94         }
  95         return NULL;
  96 }
  97
  98 static void kvm_assigned_dev_interrupt_work_handler(struct work_struct *work)
  99 {
 100         struct kvm_assigned_dev_kernel *assigned_dev;
 101
 102         assigned_dev = container_of(work, struct kvm_assigned_dev_kernel,
 103                                     interrupt_work);
 104
 105         /* This is taken to safely inject irq inside the guest. When
 106          * the interrupt injection (or the ioapic code) uses a
 107          * finer-grained lock, update this
 108          */
 109         mutex_lock(&assigned_dev->kvm->lock);
 110         kvm_set_irq(assigned_dev->kvm, assigned_dev->irq_source_id,
 111                     assigned_dev->guest_irq, 1);
 112
 113         if (assigned_dev->irq_requested_type & KVM_ASSIGNED_DEV_GUEST_MSI) {
 114                 enable_irq(assigned_dev->host_irq);
 115                 assigned_dev->host_irq_disabled = false;
 116         }
 117         mutex_unlock(&assigned_dev->kvm->lock);
 118 }
 119
 120 static irqreturn_t kvm_assigned_dev_intr(int irq, void *dev_id)
 121 {
 122         struct kvm_assigned_dev_kernel *assigned_dev =
 123                 (struct kvm_assigned_dev_kernel *) dev_id;
 124
 125         schedule_work(&assigned_dev->interrupt_work);
 126
 127         disable_irq_nosync(irq);
 128         assigned_dev->host_irq_disabled = true;
 129
 130         return IRQ_HANDLED;
 131 }
 132
 133 /* Ack the irq line for an assigned device */
 134 static void kvm_assigned_dev_ack_irq(struct kvm_irq_ack_notifier *kian)
 135 {
 136         struct kvm_assigned_dev_kernel *dev;
 137
 138         if (kian->gsi == -1)
 139                 return;
 140
 141         dev = container_of(kian, struct kvm_assigned_dev_kernel,
 142                            ack_notifier);
 143
 144         kvm_set_irq(dev->kvm, dev->irq_source_id, dev->guest_irq, 0);
 145
 146         /* The guest irq may be shared so this ack may be
 147          * from another device.
 148          */
 149         if (dev->host_irq_disabled) {
 150                 enable_irq(dev->host_irq);
 151                 dev->host_irq_disabled = false;
 152         }
 153 }
 154
 155 /* The function implicit hold kvm->lock mutex due to cancel_work_sync() */
 156 static void kvm_free_assigned_irq(struct kvm *kvm,
 157                                   struct kvm_assigned_dev_kernel *assigned_dev)
 158 {
 159         if (!irqchip_in_kernel(kvm))
 160                 return;
 161
 162         kvm_unregister_irq_ack_notifier(&assigned_dev->ack_notifier);
 163
 164         if (assigned_dev->irq_source_id != -1)
 165                 kvm_free_irq_source_id(kvm, assigned_dev->irq_source_id);
 166         assigned_dev->irq_source_id = -1;
 167
 168         if (!assigned_dev->irq_requested_type)
 169                 return;
 170
 171         /*
 172          * In kvm_free_device_irq, cancel_work_sync return true if:
 173          * 1. work is scheduled, and then cancelled.
 174          * 2. work callback is executed.
 175          *
 176          * The first one ensured that the irq is disabled and no more events
 177          * would happen. But for the second one, the irq may be enabled (e.g.
 178          * for MSI). So we disable irq here to prevent further events.
 179          *
 180          * Notice this maybe result in nested disable if the interrupt type is
 181          * INTx, but it's OK for we are going to free it.
 182          *
 183          * If this function is a part of VM destroy, please ensure that till
 184          * now, the kvm state is still legal for probably we also have to wait
 185          * interrupt_work done.
 186          */
 187         disable_irq_nosync(assigned_dev->host_irq);
 188         cancel_work_sync(&assigned_dev->interrupt_work);
 189
 190         free_irq(assigned_dev->host_irq, (void *)assigned_dev);
 191
 192         if (assigned_dev->irq_requested_type & KVM_ASSIGNED_DEV_HOST_MSI)
 193                 pci_disable_msi(assigned_dev->dev);
 194
 195         assigned_dev->irq_requested_type = 0;
 196 }
 197
 198
 199 static void kvm_free_assigned_device(struct kvm *kvm,
 200                                      struct kvm_assigned_dev_kernel
 201                                      *assigned_dev)
 202 {
 203         kvm_free_assigned_irq(kvm, assigned_dev);
 204
 205         pci_reset_function(assigned_dev->dev);
 206
 207         pci_release_regions(assigned_dev->dev);
 208         pci_disable_device(assigned_dev->dev);
 209         pci_dev_put(assigned_dev->dev);
 210
 211         list_del(&assigned_dev->list);
 212         kfree(assigned_dev);
 213 }
 214
 215 void kvm_free_all_assigned_devices(struct kvm *kvm)
 216 {
 217         struct list_head *ptr, *ptr2;
 218         struct kvm_assigned_dev_kernel *assigned_dev;
 219
 220         list_for_each_safe(ptr, ptr2, &kvm->arch.assigned_dev_head) {
 221                 assigned_dev = list_entry(ptr,
 222                                           struct kvm_assigned_dev_kernel,
 223                                           list);
 224
 225                 kvm_free_assigned_device(kvm, assigned_dev);
 226         }
 227 }
 228
 229 static int assigned_device_update_intx(struct kvm *kvm,
 230                         struct kvm_assigned_dev_kernel *adev,
 231                         struct kvm_assigned_irq *airq)
 232 {
 233         adev->guest_irq = airq->guest_irq;
 234         adev->ack_notifier.gsi = airq->guest_irq;
 235
 236         if (adev->irq_requested_type & KVM_ASSIGNED_DEV_HOST_INTX)
 237                 return 0;
 238
 239         if (irqchip_in_kernel(kvm)) {
 240                 if (!msi2intx &&
 241                     (adev->irq_requested_type & KVM_ASSIGNED_DEV_HOST_MSI)) {
 242                         free_irq(adev->host_irq, (void *)adev);
 243                         pci_disable_msi(adev->dev);
 244                 }
 245
 246                 if (!capable(CAP_SYS_RAWIO))
 247                         return -EPERM;
 248
 249                 if (airq->host_irq)
 250                         adev->host_irq = airq->host_irq;
 251                 else
 252                         adev->host_irq = adev->dev->irq;
 253
 254                 /* Even though this is PCI, we don't want to use shared
 255                  * interrupts. Sharing host devices with guest-assigned devices
 256                  * on the same interrupt line is not a happy situation: there
 257                  * are going to be long delays in accepting, acking, etc.
 258                  */
 259                 if (request_irq(adev->host_irq, kvm_assigned_dev_intr,
 260                                 0, "kvm_assigned_intx_device", (void *)adev))
 261                         return -EIO;
 262         }
 263
 264         adev->irq_requested_type = KVM_ASSIGNED_DEV_GUEST_INTX |
 265                                    KVM_ASSIGNED_DEV_HOST_INTX;
 266         return 0;
 267 }
 268
 269 #ifdef CONFIG_X86
 270 static int assigned_device_update_msi(struct kvm *kvm,
 271                         struct kvm_assigned_dev_kernel *adev,
 272                         struct kvm_assigned_irq *airq)
 273 {
 274         int r;
 275
 276         adev->guest_irq = airq->guest_irq;
 277         if (airq->flags & KVM_DEV_IRQ_ASSIGN_ENABLE_MSI) {
 278                 /* x86 don't care upper address of guest msi message addr */
 279                 adev->irq_requested_type |= KVM_ASSIGNED_DEV_GUEST_MSI;
 280                 adev->irq_requested_type &= ~KVM_ASSIGNED_DEV_GUEST_INTX;
 281                 adev->ack_notifier.gsi = -1;
 282         } else if (msi2intx) {
 283                 adev->irq_requested_type |= KVM_ASSIGNED_DEV_GUEST_INTX;
 284                 adev->irq_requested_type &= ~KVM_ASSIGNED_DEV_GUEST_MSI;
 285                 adev->ack_notifier.gsi = airq->guest_irq;
 286         } else {
 287                 /*
 288                  * Guest require to disable device MSI, we disable MSI and
 289                  * re-enable INTx by default again. Notice it's only for
 290                  * non-msi2intx.
 291                  */
 292                 assigned_device_update_intx(kvm, adev, airq);
 293                 return 0;
 294         }
 295
 296         if (adev->irq_requested_type & KVM_ASSIGNED_DEV_HOST_MSI)
 297                 return 0;
 298
 299         if (irqchip_in_kernel(kvm)) {
 300                 if (!msi2intx) {
 301                         if (adev->irq_requested_type &
 302                                         KVM_ASSIGNED_DEV_HOST_INTX)
 303                                 free_irq(adev->host_irq, (void *)adev);
 304
 305                         r = pci_enable_msi(adev->dev);
 306                         if (r)
 307                                 return r;
 308                 }
 309
 310                 adev->host_irq = adev->dev->irq;
 311                 if (request_irq(adev->host_irq, kvm_assigned_dev_intr, 0,
 312                                 "kvm_assigned_msi_device", (void *)adev))
 313                         return -EIO;
 314         }
 315
 316         if (!msi2intx)
 317                 adev->irq_requested_type = KVM_ASSIGNED_DEV_GUEST_MSI;
 318
 319         adev->irq_requested_type |= KVM_ASSIGNED_DEV_HOST_MSI;
 320         return 0;
 321 }
 322 #endif
 323
 324 static int kvm_vm_ioctl_assign_irq(struct kvm *kvm,
 325                                    struct kvm_assigned_irq
 326                                    *assigned_irq)
 327 {
 328         int r = 0;
 329         struct kvm_assigned_dev_kernel *match;
 330         u32 current_flags = 0, changed_flags;
 331
 332         mutex_lock(&kvm->lock);
 333
 334         match = kvm_find_assigned_dev(&kvm->arch.assigned_dev_head,
 335                                       assigned_irq->assigned_dev_id);
 336         if (!match) {
 337                 mutex_unlock(&kvm->lock);
 338                 return -EINVAL;
 339         }
 340
 341         if (!match->irq_requested_type) {
 342                 INIT_WORK(&match->interrupt_work,
 343                                 kvm_assigned_dev_interrupt_work_handler);
 344                 if (irqchip_in_kernel(kvm)) {
 345                         /* Register ack nofitier */
 346                         match->ack_notifier.gsi = -1;
 347                         match->ack_notifier.irq_acked =
 348                                         kvm_assigned_dev_ack_irq;
 349                         kvm_register_irq_ack_notifier(kvm,
 350                                         &match->ack_notifier);
 351
 352                         /* Request IRQ source ID */
 353                         r = kvm_request_irq_source_id(kvm);
 354                         if (r < 0)
 355                                 goto out_release;
 356                         else
 357                                 match->irq_source_id = r;
 358
 359 #ifdef CONFIG_X86
 360                         /* Determine host device irq type, we can know the
 361                          * result from dev->msi_enabled */
 362                         if (msi2intx)
 363                                 pci_enable_msi(match->dev);
 364 #endif
 365                 }
 366         }
 367
 368         if ((match->irq_requested_type & KVM_ASSIGNED_DEV_HOST_MSI) &&
 369                  (match->irq_requested_type & KVM_ASSIGNED_DEV_GUEST_MSI))
 370                 current_flags |= KVM_DEV_IRQ_ASSIGN_ENABLE_MSI;
 371
 372         changed_flags = assigned_irq->flags ^ current_flags;
 373
 374         if ((changed_flags & KVM_DEV_IRQ_ASSIGN_MSI_ACTION) ||
 375             (msi2intx && match->dev->msi_enabled)) {
 376 #ifdef CONFIG_X86
 377                 r = assigned_device_update_msi(kvm, match, assigned_irq);
 378                 if (r) {
 379                         printk(KERN_WARNING "kvm: failed to enable "
 380                                         "MSI device!\n");
 381                         goto out_release;
 382                 }
 383 #else
 384                 r = -ENOTTY;
 385 #endif
 386         } else if (assigned_irq->host_irq == 0 && match->dev->irq == 0) {
 387                 /* Host device IRQ 0 means don't support INTx */
 388                 if (!msi2intx) {
 389                         printk(KERN_WARNING
 390                                "kvm: wait device to enable MSI!\n");
 391                         r = 0;
 392                 } else {
 393                         printk(KERN_WARNING
 394                                "kvm: failed to enable MSI device!\n");
 395                         r = -ENOTTY;
 396                         goto out_release;
 397                 }
 398         } else {
 399                 /* Non-sharing INTx mode */
 400                 r = assigned_device_update_intx(kvm, match, assigned_irq);
 401                 if (r) {
 402                         printk(KERN_WARNING "kvm: failed to enable "
 403                                         "INTx device!\n");
 404                         goto out_release;
 405                 }
 406         }
 407
 408         mutex_unlock(&kvm->lock);
 409         return r;
 410 out_release:
 411         mutex_unlock(&kvm->lock);
 412         kvm_free_assigned_device(kvm, match);
 413         return r;
 414 }
 415
 416 static int kvm_vm_ioctl_assign_device(struct kvm *kvm,
 417                                       struct kvm_assigned_pci_dev *assigned_dev)
 418 {
 419         int r = 0;
 420         struct kvm_assigned_dev_kernel *match;
 421         struct pci_dev *dev;
 422
 423         down_read(&kvm->slots_lock);
 424         mutex_lock(&kvm->lock);
 425
 426         match = kvm_find_assigned_dev(&kvm->arch.assigned_dev_head,
 427                                       assigned_dev->assigned_dev_id);
 428         if (match) {
 429                 /* device already assigned */
 430                 r = -EINVAL;
 431                 goto out;
 432         }
 433
 434         match = kzalloc(sizeof(struct kvm_assigned_dev_kernel), GFP_KERNEL);
 435         if (match == NULL) {
 436                 printk(KERN_INFO "%s: Couldn't allocate memory\n",
 437                        __func__);
 438                 r = -ENOMEM;
 439                 goto out;
 440         }
 441         dev = pci_get_bus_and_slot(assigned_dev->busnr,
 442                                    assigned_dev->devfn);
 443         if (!dev) {
 444                 printk(KERN_INFO "%s: host device not found\n", __func__);
 445                 r = -EINVAL;
 446                 goto out_free;
 447         }
 448         if (pci_enable_device(dev)) {
 449                 printk(KERN_INFO "%s: Could not enable PCI device\n", __func__);
 450                 r = -EBUSY;
 451                 goto out_put;
 452         }
 453         r = pci_request_regions(dev, "kvm_assigned_device");
 454         if (r) {
 455                 printk(KERN_INFO "%s: Could not get access to device regions\n",
 456                        __func__);
 457                 goto out_disable;
 458         }
 459
 460         pci_reset_function(dev);
 461
 462         match->assigned_dev_id = assigned_dev->assigned_dev_id;
 463         match->host_busnr = assigned_dev->busnr;
 464         match->host_devfn = assigned_dev->devfn;
 465         match->flags = assigned_dev->flags;
 466         match->dev = dev;
 467         match->irq_source_id = -1;
 468         match->kvm = kvm;
 469
 470         list_add(&match->list, &kvm->arch.assigned_dev_head);
 471
 472         if (assigned_dev->flags & KVM_DEV_ASSIGN_ENABLE_IOMMU) {
 473                 if (!kvm->arch.iommu_domain) {
 474                         r = kvm_iommu_map_guest(kvm);
 475                         if (r)
 476                                 goto out_list_del;
 477                 }
 478                 r = kvm_assign_device(kvm, match);
 479                 if (r)
 480                         goto out_list_del;
 481         }
 482
 483 out:
 484         mutex_unlock(&kvm->lock);
 485         up_read(&kvm->slots_lock);
 486         return r;
 487 out_list_del:
 488         list_del(&match->list);
 489         pci_release_regions(dev);
 490 out_disable:
 491         pci_disable_device(dev);
 492 out_put:
 493         pci_dev_put(dev);
 494 out_free:
 495         kfree(match);
 496         mutex_unlock(&kvm->lock);
 497         up_read(&kvm->slots_lock);
 498         return r;
 499 }
 500 #endif
 501
 502 #ifdef KVM_CAP_DEVICE_DEASSIGNMENT
 503 static int kvm_vm_ioctl_deassign_device(struct kvm *kvm,
 504                 struct kvm_assigned_pci_dev *assigned_dev)
 505 {
 506         int r = 0;
 507         struct kvm_assigned_dev_kernel *match;
 508
 509         mutex_lock(&kvm->lock);
 510
 511         match = kvm_find_assigned_dev(&kvm->arch.assigned_dev_head,
 512                                       assigned_dev->assigned_dev_id);
 513         if (!match) {
 514                 printk(KERN_INFO "%s: device hasn't been assigned before, "
 515                   "so cannot be deassigned\n", __func__);
 516                 r = -EINVAL;
 517                 goto out;
 518         }
 519
 520         if (match->flags & KVM_DEV_ASSIGN_ENABLE_IOMMU)
 521                 kvm_deassign_device(kvm, match);
 522
 523         kvm_free_assigned_device(kvm, match);
 524
 525 out:
 526         mutex_unlock(&kvm->lock);
 527         return r;
 528 }
 529 #endif
 530
 531 static inline int valid_vcpu(int n)
 532 {
 533         return likely(n >= 0 && n < KVM_MAX_VCPUS);
 534 }
 535
 536 inline int kvm_is_mmio_pfn(pfn_t pfn)
 537 {
 538         if (pfn_valid(pfn)) {
 539                 struct page *page = compound_head(pfn_to_page(pfn));
 540                 return PageReserved(page);
 541         }
 542
 543         return true;
 544 }
 545
 546 /*
 547  * Switches to specified vcpu, until a matching vcpu_put()
 548  */
 549 void vcpu_load(struct kvm_vcpu *vcpu)
 550 {
 551         int cpu;
 552
 553         mutex_lock(&vcpu->mutex);
 554         cpu = get_cpu();
 555         preempt_notifier_register(&vcpu->preempt_notifier);
 556         kvm_arch_vcpu_load(vcpu, cpu);
 557         put_cpu();
 558 }
 559
 560 void vcpu_put(struct kvm_vcpu *vcpu)
 561 {
 562         preempt_disable();
 563         kvm_arch_vcpu_put(vcpu);
 564         preempt_notifier_unregister(&vcpu->preempt_notifier);
 565         preempt_enable();
 566         mutex_unlock(&vcpu->mutex);
 567 }
 568
 569 static void ack_flush(void *_completed)
 570 {
 571 }
 572
 573 static bool make_all_cpus_request(struct kvm *kvm, unsigned int req)
 574 {
 575         int i, cpu, me;
 576         cpumask_var_t cpus;
 577         bool called = true;
 578         struct kvm_vcpu *vcpu;
 579
 580         if (alloc_cpumask_var(&cpus, GFP_ATOMIC))
 581                 cpumask_clear(cpus);
 582
 583         me = get_cpu();
 584         for (i = 0; i < KVM_MAX_VCPUS; ++i) {
 585                 vcpu = kvm->vcpus[i];
 586                 if (!vcpu)
 587                         continue;
 588                 if (test_and_set_bit(req, &vcpu->requests))
 589                         continue;
 590                 cpu = vcpu->cpu;
 591                 if (cpus != NULL && cpu != -1 && cpu != me)
 592                         cpumask_set_cpu(cpu, cpus);
 593         }
 594         if (unlikely(cpus == NULL))
 595                 smp_call_function_many(cpu_online_mask, ack_flush, NULL, 1);
 596         else if (!cpumask_empty(cpus))
 597                 smp_call_function_many(cpus, ack_flush, NULL, 1);
 598         else
 599                 called = false;
 600         put_cpu();
 601         free_cpumask_var(cpus);
 602         return called;
 603 }
 604
 605 void kvm_flush_remote_tlbs(struct kvm *kvm)
 606 {
 607         if (make_all_cpus_request(kvm, KVM_REQ_TLB_FLUSH))
 608                 ++kvm->stat.remote_tlb_flush;
 609 }
 610
 611 void kvm_reload_remote_mmus(struct kvm *kvm)
 612 {
 613         make_all_cpus_request(kvm, KVM_REQ_MMU_RELOAD);
 614 }
 615
 616 int kvm_vcpu_init(struct kvm_vcpu *vcpu, struct kvm *kvm, unsigned id)
 617 {
 618         struct page *page;
 619         int r;
 620
 621         mutex_init(&vcpu->mutex);
 622         vcpu->cpu = -1;
 623         vcpu->kvm = kvm;
 624         vcpu->vcpu_id = id;
 625         init_waitqueue_head(&vcpu->wq);
 626
 627         page = alloc_page(GFP_KERNEL | __GFP_ZERO);
 628         if (!page) {
 629                 r = -ENOMEM;
 630                 goto fail;
 631         }
 632         vcpu->run = page_address(page);
 633
 634         r = kvm_arch_vcpu_init(vcpu);
 635         if (r < 0)
 636                 goto fail_free_run;
 637         return 0;
 638
 639 fail_free_run:
 640         free_page((unsigned long)vcpu->run);
 641 fail:
 642         return r;
 643 }
 644 EXPORT_SYMBOL_GPL(kvm_vcpu_init);
 645
 646 void kvm_vcpu_uninit(struct kvm_vcpu *vcpu)
 647 {
 648         kvm_arch_vcpu_uninit(vcpu);
 649         free_page((unsigned long)vcpu->run);
 650 }
 651 EXPORT_SYMBOL_GPL(kvm_vcpu_uninit);
 652
 653 #if defined(CONFIG_MMU_NOTIFIER) && defined(KVM_ARCH_WANT_MMU_NOTIFIER)
 654 static inline struct kvm *mmu_notifier_to_kvm(struct mmu_notifier *mn)
 655 {
 656         return container_of(mn, struct kvm, mmu_notifier);
 657 }
 658
 659 static void kvm_mmu_notifier_invalidate_page(struct mmu_notifier *mn,
 660                                              struct mm_struct *mm,
 661                                              unsigned long address)
 662 {
 663         struct kvm *kvm = mmu_notifier_to_kvm(mn);
 664         int need_tlb_flush;
 665
 666         /*
 667          * When ->invalidate_page runs, the linux pte has been zapped
 668          * already but the page is still allocated until
 669          * ->invalidate_page returns. So if we increase the sequence
 670          * here the kvm page fault will notice if the spte can't be
 671          * established because the page is going to be freed. If
 672          * instead the kvm page fault establishes the spte before
 673          * ->invalidate_page runs, kvm_unmap_hva will release it
 674          * before returning.
 675          *
 676          * The sequence increase only need to be seen at spin_unlock
 677          * time, and not at spin_lock time.
 678          *
 679          * Increasing the sequence after the spin_unlock would be
 680          * unsafe because the kvm page fault could then establish the
 681          * pte after kvm_unmap_hva returned, without noticing the page
 682          * is going to be freed.
 683          */
 684         spin_lock(&kvm->mmu_lock);
 685         kvm->mmu_notifier_seq++;
 686         need_tlb_flush = kvm_unmap_hva(kvm, address);
 687         spin_unlock(&kvm->mmu_lock);
 688
 689         /* we've to flush the tlb before the pages can be freed */
 690         if (need_tlb_flush)
 691                 kvm_flush_remote_tlbs(kvm);
 692
 693 }
 694
 695 static void kvm_mmu_notifier_invalidate_range_start(struct mmu_notifier *mn,
 696                                                     struct mm_struct *mm,
 697                                                     unsigned long start,
 698                                                     unsigned long end)
 699 {
 700         struct kvm *kvm = mmu_notifier_to_kvm(mn);
 701         int need_tlb_flush = 0;
 702
 703         spin_lock(&kvm->mmu_lock);
 704         /*
 705          * The count increase must become visible at unlock time as no
 706          * spte can be established without taking the mmu_lock and
 707          * count is also read inside the mmu_lock critical section.
 708          */
 709         kvm->mmu_notifier_count++;
 710         for (; start < end; start += PAGE_SIZE)
 711                 need_tlb_flush |= kvm_unmap_hva(kvm, start);
 712         spin_unlock(&kvm->mmu_lock);
 713
 714         /* we've to flush the tlb before the pages can be freed */
 715         if (need_tlb_flush)
 716                 kvm_flush_remote_tlbs(kvm);
 717 }
 718
 719 static void kvm_mmu_notifier_invalidate_range_end(struct mmu_notifier *mn,
 720                                                   struct mm_struct *mm,
 721                                                   unsigned long start,
 722                                                   unsigned long end)
 723 {
 724         struct kvm *kvm = mmu_notifier_to_kvm(mn);
 725
 726         spin_lock(&kvm->mmu_lock);
 727         /*
 728          * This sequence increase will notify the kvm page fault that
 729          * the page that is going to be mapped in the spte could have
 730          * been freed.
 731          */
 732         kvm->mmu_notifier_seq++;
 733         /*
 734          * The above sequence increase must be visible before the
 735          * below count decrease but both values are read by the kvm
 736          * page fault under mmu_lock spinlock so we don't need to add
 737          * a smb_wmb() here in between the two.
 738          */
 739         kvm->mmu_notifier_count--;
 740         spin_unlock(&kvm->mmu_lock);
 741
 742         BUG_ON(kvm->mmu_notifier_count < 0);
 743 }
 744
 745 static int kvm_mmu_notifier_clear_flush_young(struct mmu_notifier *mn,
 746                                               struct mm_struct *mm,
 747                                               unsigned long address)
 748 {
 749         struct kvm *kvm = mmu_notifier_to_kvm(mn);
 750         int young;
 751
 752         spin_lock(&kvm->mmu_lock);
 753         young = kvm_age_hva(kvm, address);
 754         spin_unlock(&kvm->mmu_lock);
 755
 756         if (young)
 757                 kvm_flush_remote_tlbs(kvm);
 758
 759         return young;
 760 }
 761
 762 static void kvm_mmu_notifier_release(struct mmu_notifier *mn,
 763                                      struct mm_struct *mm)
 764 {
 765         struct kvm *kvm = mmu_notifier_to_kvm(mn);
 766         kvm_arch_flush_shadow(kvm);
 767 }
 768
 769 static const struct mmu_notifier_ops kvm_mmu_notifier_ops = {
 770         .invalidate_page        = kvm_mmu_notifier_invalidate_page,
 771         .invalidate_range_start = kvm_mmu_notifier_invalidate_range_start,
 772         .invalidate_range_end   = kvm_mmu_notifier_invalidate_range_end,
 773         .clear_flush_young      = kvm_mmu_notifier_clear_flush_young,
 774         .release                = kvm_mmu_notifier_release,
 775 };
 776 #endif /* CONFIG_MMU_NOTIFIER && KVM_ARCH_WANT_MMU_NOTIFIER */
 777
 778 static struct kvm *kvm_create_vm(void)
 779 {
 780         struct kvm *kvm = kvm_arch_create_vm();
 781 #ifdef KVM_COALESCED_MMIO_PAGE_OFFSET
 782         struct page *page;
 783 #endif
 784
 785         if (IS_ERR(kvm))
 786                 goto out;
 787 #ifdef CONFIG_HAVE_KVM_IRQCHIP
 788         INIT_LIST_HEAD(&kvm->irq_routing);
 789         INIT_HLIST_HEAD(&kvm->mask_notifier_list);
 790 #endif
 791
 792 #ifdef KVM_COALESCED_MMIO_PAGE_OFFSET
 793         page = alloc_page(GFP_KERNEL | __GFP_ZERO);
 794         if (!page) {
 795                 kfree(kvm);
 796                 return ERR_PTR(-ENOMEM);
 797         }
 798         kvm->coalesced_mmio_ring =
 799                         (struct kvm_coalesced_mmio_ring *)page_address(page);
 800 #endif
 801
 802 #if defined(CONFIG_MMU_NOTIFIER) && defined(KVM_ARCH_WANT_MMU_NOTIFIER)
 803         {
 804                 int err;
 805                 kvm->mmu_notifier.ops = &kvm_mmu_notifier_ops;
 806                 err = mmu_notifier_register(&kvm->mmu_notifier, current->mm);
 807                 if (err) {
 808 #ifdef KVM_COALESCED_MMIO_PAGE_OFFSET
 809                         put_page(page);
 810 #endif
 811                         kfree(kvm);
 812                         return ERR_PTR(err);
 813                 }
 814         }
 815 #endif
 816
 817         kvm->mm = current->mm;
 818         atomic_inc(&kvm->mm->mm_count);
 819         spin_lock_init(&kvm->mmu_lock);
 820         kvm_io_bus_init(&kvm->pio_bus);
 821         mutex_init(&kvm->lock);
 822         kvm_io_bus_init(&kvm->mmio_bus);
 823         init_rwsem(&kvm->slots_lock);
 824         atomic_set(&kvm->users_count, 1);
 825         spin_lock(&kvm_lock);
 826         list_add(&kvm->vm_list, &vm_list);
 827         spin_unlock(&kvm_lock);
 828 #ifdef KVM_COALESCED_MMIO_PAGE_OFFSET
 829         kvm_coalesced_mmio_init(kvm);
 830 #endif
 831 out:
 832         return kvm;
 833 }
 834
 835 /*
 836  * Free any memory in @free but not in @dont.
 837  */
 838 static void kvm_free_physmem_slot(struct kvm_memory_slot *free,
 839                                   struct kvm_memory_slot *dont)
 840 {
 841         if (!dont || free->rmap != dont->rmap)
 842                 vfree(free->rmap);
 843
 844         if (!dont || free->dirty_bitmap != dont->dirty_bitmap)
 845                 vfree(free->dirty_bitmap);
 846
 847         if (!dont || free->lpage_info != dont->lpage_info)
 848                 vfree(free->lpage_info);
 849
 850         free->npages = 0;
 851         free->dirty_bitmap = NULL;
 852         free->rmap = NULL;
 853         free->lpage_info = NULL;
 854 }
 855
 856 void kvm_free_physmem(struct kvm *kvm)
 857 {
 858         int i;
 859
 860         for (i = 0; i < kvm->nmemslots; ++i)
 861                 kvm_free_physmem_slot(&kvm->memslots[i], NULL);
 862 }
 863
 864 static void kvm_destroy_vm(struct kvm *kvm)
 865 {
 866         struct mm_struct *mm = kvm->mm;
 867
 868         kvm_arch_sync_events(kvm);
 869         spin_lock(&kvm_lock);
 870         list_del(&kvm->vm_list);
 871         spin_unlock(&kvm_lock);
 872         kvm_free_irq_routing(kvm);
 873         kvm_io_bus_destroy(&kvm->pio_bus);
 874         kvm_io_bus_destroy(&kvm->mmio_bus);
 875 #ifdef KVM_COALESCED_MMIO_PAGE_OFFSET
 876         if (kvm->coalesced_mmio_ring != NULL)
 877                 free_page((unsigned long)kvm->coalesced_mmio_ring);
 878 #endif
 879 #if defined(CONFIG_MMU_NOTIFIER) && defined(KVM_ARCH_WANT_MMU_NOTIFIER)
 880         mmu_notifier_unregister(&kvm->mmu_notifier, kvm->mm);
 881 #endif
 882         kvm_arch_destroy_vm(kvm);
 883         mmdrop(mm);
 884 }
 885
 886 void kvm_get_kvm(struct kvm *kvm)
 887 {
 888         atomic_inc(&kvm->users_count);
 889 }
 890 EXPORT_SYMBOL_GPL(kvm_get_kvm);
 891
 892 void kvm_put_kvm(struct kvm *kvm)
 893 {
 894         if (atomic_dec_and_test(&kvm->users_count))
 895                 kvm_destroy_vm(kvm);
 896 }
 897 EXPORT_SYMBOL_GPL(kvm_put_kvm);
 898
 899
 900 static int kvm_vm_release(struct inode *inode, struct file *filp)
 901 {
 902         struct kvm *kvm = filp->private_data;
 903
 904         kvm_put_kvm(kvm);
 905         return 0;
 906 }
 907
 908 /*
 909  * Allocate some memory and give it an address in the guest physical address
 910  * space.
 911  *
 912  * Discontiguous memory is allowed, mostly for framebuffers.
 913  *
 914  * Must be called holding mmap_sem for write.
 915  */
 916 int __kvm_set_memory_region(struct kvm *kvm,
 917                             struct kvm_userspace_memory_region *mem,
 918                             int user_alloc)
 919 {
 920         int r;
 921         gfn_t base_gfn;
 922         unsigned long npages;
 923         unsigned long i;
 924         struct kvm_memory_slot *memslot;
 925         struct kvm_memory_slot old, new;
 926
 927         r = -EINVAL;
 928         /* General sanity checks */
 929         if (mem->memory_size & (PAGE_SIZE - 1))
 930                 goto out;
 931         if (mem->guest_phys_addr & (PAGE_SIZE - 1))
 932                 goto out;
 933         if (user_alloc && (mem->userspace_addr & (PAGE_SIZE - 1)))
 934                 goto out;
 935         if (mem->slot >= KVM_MEMORY_SLOTS + KVM_PRIVATE_MEM_SLOTS)
 936                 goto out;
 937         if (mem->guest_phys_addr + mem->memory_size < mem->guest_phys_addr)
 938                 goto out;
 939
 940         memslot = &kvm->memslots[mem->slot];
 941         base_gfn = mem->guest_phys_addr >> PAGE_SHIFT;
 942         npages = mem->memory_size >> PAGE_SHIFT;
 943
 944         if (!npages)
 945                 mem->flags &= ~KVM_MEM_LOG_DIRTY_PAGES;
 946
 947         new = old = *memslot;
 948
 949         new.base_gfn = base_gfn;
 950         new.npages = npages;
 951         new.flags = mem->flags;
 952
 953         /* Disallow changing a memory slot's size. */
 954         r = -EINVAL;
 955         if (npages && old.npages && npages != old.npages)
 956                 goto out_free;
 957
 958         /* Check for overlaps */
 959         r = -EEXIST;
 960         for (i = 0; i < KVM_MEMORY_SLOTS; ++i) {
 961                 struct kvm_memory_slot *s = &kvm->memslots[i];
 962
 963                 if (s == memslot)
 964                         continue;
 965                 if (!((base_gfn + npages <= s->base_gfn) ||
 966                       (base_gfn >= s->base_gfn + s->npages)))
 967                         goto out_free;
 968         }
 969
 970         /* Free page dirty bitmap if unneeded */
 971         if (!(new.flags & KVM_MEM_LOG_DIRTY_PAGES))
 972                 new.dirty_bitmap = NULL;
 973
 974         r = -ENOMEM;
 975
 976         /* Allocate if a slot is being created */
 977 #ifndef CONFIG_S390
 978         if (npages && !new.rmap) {
 979                 new.rmap = vmalloc(npages * sizeof(struct page *));
 980
 981                 if (!new.rmap)
 982                         goto out_free;
 983
 984                 memset(new.rmap, 0, npages * sizeof(*new.rmap));
 985
 986                 new.user_alloc = user_alloc;
 987                 /*
 988                  * hva_to_rmmap() serialzies with the mmu_lock and to be
 989                  * safe it has to ignore memslots with !user_alloc &&
 990                  * !userspace_addr.
 991                  */
 992                 if (user_alloc)
 993                         new.userspace_addr = mem->userspace_addr;
 994                 else
 995                         new.userspace_addr = 0;
 996         }
 997         if (npages && !new.lpage_info) {
 998                 int largepages = npages / KVM_PAGES_PER_HPAGE;
 999                 if (npages % KVM_PAGES_PER_HPAGE)
1000                         largepages++;
1001                 if (base_gfn % KVM_PAGES_PER_HPAGE)
1002                         largepages++;
1003
1004                 new.lpage_info = vmalloc(largepages * sizeof(*new.lpage_info));
1005
1006                 if (!new.lpage_info)
1007                         goto out_free;
1008
1009                 memset(new.lpage_info, 0, largepages * sizeof(*new.lpage_info));
1010
1011                 if (base_gfn % KVM_PAGES_PER_HPAGE)
1012                         new.lpage_info[0].write_count = 1;
1013                 if ((base_gfn+npages) % KVM_PAGES_PER_HPAGE)
1014                         new.lpage_info[largepages-1].write_count = 1;
1015         }
1016
1017         /* Allocate page dirty bitmap if needed */
1018         if ((new.flags & KVM_MEM_LOG_DIRTY_PAGES) && !new.dirty_bitmap) {
1019                 unsigned dirty_bytes = ALIGN(npages, BITS_PER_LONG) / 8;
1020
1021                 new.dirty_bitmap = vmalloc(dirty_bytes);
1022                 if (!new.dirty_bitmap)
1023                         goto out_free;
1024                 memset(new.dirty_bitmap, 0, dirty_bytes);
1025         }
1026 #endif /* not defined CONFIG_S390 */
1027
1028         if (!npages)
1029                 kvm_arch_flush_shadow(kvm);
1030
1031         spin_lock(&kvm->mmu_lock);
1032         if (mem->slot >= kvm->nmemslots)
1033                 kvm->nmemslots = mem->slot + 1;
1034
1035         *memslot = new;
1036         spin_unlock(&kvm->mmu_lock);
1037
1038         r = kvm_arch_set_memory_region(kvm, mem, old, user_alloc);
1039         if (r) {
1040                 spin_lock(&kvm->mmu_lock);
1041                 *memslot = old;
1042                 spin_unlock(&kvm->mmu_lock);
1043                 goto out_free;
1044         }
1045
1046         kvm_free_physmem_slot(&old, npages ? &new : NULL);
1047         /* Slot deletion case: we have to update the current slot */
1048         if (!npages)
1049                 *memslot = old;
1050 #ifdef CONFIG_DMAR
1051         /* map the pages in iommu page table */
1052         r = kvm_iommu_map_pages(kvm, base_gfn, npages);
1053         if (r)
1054                 goto out;
1055 #endif
1056         return 0;
1057
1058 out_free:
1059         kvm_free_physmem_slot(&new, &old);
1060 out:
1061         return r;
1062
1063 }
1064 EXPORT_SYMBOL_GPL(__kvm_set_memory_region);
1065
1066 int kvm_set_memory_region(struct kvm *kvm,
1067                           struct kvm_userspace_memory_region *mem,
1068                           int user_alloc)
1069 {
1070         int r;
1071
1072         down_write(&kvm->slots_lock);
1073         r = __kvm_set_memory_region(kvm, mem, user_alloc);
1074         up_write(&kvm->slots_lock);
1075         return r;
1076 }
1077 EXPORT_SYMBOL_GPL(kvm_set_memory_region);
1078
1079 int kvm_vm_ioctl_set_memory_region(struct kvm *kvm,
1080                                    struct
1081                                    kvm_userspace_memory_region *mem,
1082                                    int user_alloc)
1083 {
1084         if (mem->slot >= KVM_MEMORY_SLOTS)
1085                 return -EINVAL;
1086         return kvm_set_memory_region(kvm, mem, user_alloc);
1087 }
1088
1089 int kvm_get_dirty_log(struct kvm *kvm,
1090                         struct kvm_dirty_log *log, int *is_dirty)
1091 {
1092         struct kvm_memory_slot *memslot;
1093         int r, i;
1094         int n;
1095         unsigned long any = 0;
1096
1097         r = -EINVAL;
1098         if (log->slot >= KVM_MEMORY_SLOTS)
1099                 goto out;
1100
1101         memslot = &kvm->memslots[log->slot];
1102         r = -ENOENT;
1103         if (!memslot->dirty_bitmap)
1104                 goto out;
1105
1106         n = ALIGN(memslot->npages, BITS_PER_LONG) / 8;
1107
1108         for (i = 0; !any && i < n/sizeof(long); ++i)
1109                 any = memslot->dirty_bitmap[i];
1110
1111         r = -EFAULT;
1112         if (copy_to_user(log->dirty_bitmap, memslot->dirty_bitmap, n))
1113                 goto out;
1114
1115         if (any)
1116                 *is_dirty = 1;
1117
1118         r = 0;
1119 out:
1120         return r;
1121 }
1122
1123 int is_error_page(struct page *page)
1124 {
1125         return page == bad_page;
1126 }
1127 EXPORT_SYMBOL_GPL(is_error_page);
1128
1129 int is_error_pfn(pfn_t pfn)
1130 {
1131         return pfn == bad_pfn;
1132 }
1133 EXPORT_SYMBOL_GPL(is_error_pfn);
1134
1135 static inline unsigned long bad_hva(void)
1136 {
1137         return PAGE_OFFSET;
1138 }
1139
1140 int kvm_is_error_hva(unsigned long addr)
1141 {
1142         return addr == bad_hva();
1143 }
1144 EXPORT_SYMBOL_GPL(kvm_is_error_hva);
1145
1146 struct kvm_memory_slot *gfn_to_memslot_unaliased(struct kvm *kvm, gfn_t gfn)
1147 {
1148         int i;
1149
1150         for (i = 0; i < kvm->nmemslots; ++i) {
1151                 struct kvm_memory_slot *memslot = &kvm->memslots[i];
1152
1153                 if (gfn >= memslot->base_gfn
1154                     && gfn < memslot->base_gfn + memslot->npages)
1155                         return memslot;
1156         }
1157         return NULL;
1158 }
1159 EXPORT_SYMBOL_GPL(gfn_to_memslot_unaliased);
1160
1161 struct kvm_memory_slot *gfn_to_memslot(struct kvm *kvm, gfn_t gfn)
1162 {
1163         gfn = unalias_gfn(kvm, gfn);
1164         return gfn_to_memslot_unaliased(kvm, gfn);
1165 }
1166
1167 int kvm_is_visible_gfn(struct kvm *kvm, gfn_t gfn)
1168 {
1169         int i;
1170
1171         gfn = unalias_gfn(kvm, gfn);
1172         for (i = 0; i < KVM_MEMORY_SLOTS; ++i) {
1173                 struct kvm_memory_slot *memslot = &kvm->memslots[i];
1174
1175                 if (gfn >= memslot->base_gfn
1176                     && gfn < memslot->base_gfn + memslot->npages)
1177                         return 1;
1178         }
1179         return 0;
1180 }
1181 EXPORT_SYMBOL_GPL(kvm_is_visible_gfn);
1182
1183 unsigned long gfn_to_hva(struct kvm *kvm, gfn_t gfn)
1184 {
1185         struct kvm_memory_slot *slot;
1186
1187         gfn = unalias_gfn(kvm, gfn);
1188         slot = gfn_to_memslot_unaliased(kvm, gfn);
1189         if (!slot)
1190                 return bad_hva();
1191         return (slot->userspace_addr + (gfn - slot->base_gfn) * PAGE_SIZE);
1192 }
1193 EXPORT_SYMBOL_GPL(gfn_to_hva);
1194
1195 pfn_t gfn_to_pfn(struct kvm *kvm, gfn_t gfn)
1196 {
1197         struct page *page[1];
1198         unsigned long addr;
1199         int npages;
1200         pfn_t pfn;
1201
1202         might_sleep();
1203
1204         addr = gfn_to_hva(kvm, gfn);
1205         if (kvm_is_error_hva(addr)) {
1206                 get_page(bad_page);
1207                 return page_to_pfn(bad_page);
1208         }
1209
1210         npages = get_user_pages_fast(addr, 1, 1, page);
1211
1212         if (unlikely(npages != 1)) {
1213                 struct vm_area_struct *vma;
1214
1215                 down_read(&current->mm->mmap_sem);
1216                 vma = find_vma(current->mm, addr);
1217
1218                 if (vma == NULL || addr < vma->vm_start ||
1219                     !(vma->vm_flags & VM_PFNMAP)) {
1220                         up_read(&current->mm->mmap_sem);
1221                         get_page(bad_page);
1222                         return page_to_pfn(bad_page);
1223                 }
1224
1225                 pfn = ((addr - vma->vm_start) >> PAGE_SHIFT) + vma->vm_pgoff;
1226                 up_read(&current->mm->mmap_sem);
1227                 BUG_ON(!kvm_is_mmio_pfn(pfn));
1228         } else
1229                 pfn = page_to_pfn(page[0]);
1230
1231         return pfn;
1232 }
1233
1234 EXPORT_SYMBOL_GPL(gfn_to_pfn);
1235
1236 struct page *gfn_to_page(struct kvm *kvm, gfn_t gfn)
1237 {
1238         pfn_t pfn;
1239
1240         pfn = gfn_to_pfn(kvm, gfn);
1241         if (!kvm_is_mmio_pfn(pfn))
1242                 return pfn_to_page(pfn);
1243
1244         WARN_ON(kvm_is_mmio_pfn(pfn));
1245
1246         get_page(bad_page);
1247         return bad_page;
1248 }
1249
1250 EXPORT_SYMBOL_GPL(gfn_to_page);
1251
1252 void kvm_release_page_clean(struct page *page)
1253 {
1254         kvm_release_pfn_clean(page_to_pfn(page));
1255 }
1256 EXPORT_SYMBOL_GPL(kvm_release_page_clean);
1257
1258 void kvm_release_pfn_clean(pfn_t pfn)
1259 {
1260         if (!kvm_is_mmio_pfn(pfn))
1261                 put_page(pfn_to_page(pfn));
1262 }
1263 EXPORT_SYMBOL_GPL(kvm_release_pfn_clean);
1264
1265 void kvm_release_page_dirty(struct page *page)
1266 {
1267         kvm_release_pfn_dirty(page_to_pfn(page));
1268 }
1269 EXPORT_SYMBOL_GPL(kvm_release_page_dirty);
1270
1271 void kvm_release_pfn_dirty(pfn_t pfn)
1272 {
1273         kvm_set_pfn_dirty(pfn);
1274         kvm_release_pfn_clean(pfn);
1275 }
1276 EXPORT_SYMBOL_GPL(kvm_release_pfn_dirty);
1277
1278 void kvm_set_page_dirty(struct page *page)
1279 {
1280         kvm_set_pfn_dirty(page_to_pfn(page));
1281 }
1282 EXPORT_SYMBOL_GPL(kvm_set_page_dirty);
1283
1284 void kvm_set_pfn_dirty(pfn_t pfn)
1285 {
1286         if (!kvm_is_mmio_pfn(pfn)) {
1287                 struct page *page = pfn_to_page(pfn);
1288                 if (!PageReserved(page))
1289                         SetPageDirty(page);
1290         }
1291 }
1292 EXPORT_SYMBOL_GPL(kvm_set_pfn_dirty);
1293
1294 void kvm_set_pfn_accessed(pfn_t pfn)
1295 {
1296         if (!kvm_is_mmio_pfn(pfn))
1297                 mark_page_accessed(pfn_to_page(pfn));
1298 }
1299 EXPORT_SYMBOL_GPL(kvm_set_pfn_accessed);
1300
1301 void kvm_get_pfn(pfn_t pfn)
1302 {
1303         if (!kvm_is_mmio_pfn(pfn))
1304                 get_page(pfn_to_page(pfn));
1305 }
1306 EXPORT_SYMBOL_GPL(kvm_get_pfn);
1307
1308 static int next_segment(unsigned long len, int offset)
1309 {
1310         if (len > PAGE_SIZE - offset)
1311                 return PAGE_SIZE - offset;
1312         else
1313                 return len;
1314 }
1315
1316 int kvm_read_guest_page(struct kvm *kvm, gfn_t gfn, void *data, int offset,
1317                         int len)
1318 {
1319         int r;
1320         unsigned long addr;
1321
1322         addr = gfn_to_hva(kvm, gfn);
1323         if (kvm_is_error_hva(addr))
1324                 return -EFAULT;
1325         r = copy_from_user(data, (void __user *)addr + offset, len);
1326         if (r)
1327                 return -EFAULT;
1328         return 0;
1329 }
1330 EXPORT_SYMBOL_GPL(kvm_read_guest_page);
1331
1332 int kvm_read_guest(struct kvm *kvm, gpa_t gpa, void *data, unsigned long len)
1333 {
1334         gfn_t gfn = gpa >> PAGE_SHIFT;
1335         int seg;
1336         int offset = offset_in_page(gpa);
1337         int ret;
1338
1339         while ((seg = next_segment(len, offset)) != 0) {
1340                 ret = kvm_read_guest_page(kvm, gfn, data, offset, seg);
1341                 if (ret < 0)
1342                         return ret;
1343                 offset = 0;
1344                 len -= seg;
1345                 data += seg;
1346                 ++gfn;
1347         }
1348         return 0;
1349 }
1350 EXPORT_SYMBOL_GPL(kvm_read_guest);
1351
1352 int kvm_read_guest_atomic(struct kvm *kvm, gpa_t gpa, void *data,
1353                           unsigned long len)
1354 {
1355         int r;
1356         unsigned long addr;
1357         gfn_t gfn = gpa >> PAGE_SHIFT;
1358         int offset = offset_in_page(gpa);
1359
1360         addr = gfn_to_hva(kvm, gfn);
1361         if (kvm_is_error_hva(addr))
1362                 return -EFAULT;
1363         pagefault_disable();
1364         r = __copy_from_user_inatomic(data, (void __user *)addr + offset, len);
1365         pagefault_enable();
1366         if (r)
1367                 return -EFAULT;
1368         return 0;
1369 }
1370 EXPORT_SYMBOL(kvm_read_guest_atomic);
1371
1372 int kvm_write_guest_page(struct kvm *kvm, gfn_t gfn, const void *data,
1373                          int offset, int len)
1374 {
1375         int r;
1376         unsigned long addr;
1377
1378         addr = gfn_to_hva(kvm, gfn);
1379         if (kvm_is_error_hva(addr))
1380                 return -EFAULT;
1381         r = copy_to_user((void __user *)addr + offset, data, len);
1382         if (r)
1383                 return -EFAULT;
1384         mark_page_dirty(kvm, gfn);
1385         return 0;
1386 }
1387 EXPORT_SYMBOL_GPL(kvm_write_guest_page);
1388
1389 int kvm_write_guest(struct kvm *kvm, gpa_t gpa, const void *data,
1390                     unsigned long len)
1391 {
1392         gfn_t gfn = gpa >> PAGE_SHIFT;
1393         int seg;
1394         int offset = offset_in_page(gpa);
1395         int ret;
1396
1397         while ((seg = next_segment(len, offset)) != 0) {
1398                 ret = kvm_write_guest_page(kvm, gfn, data, offset, seg);
1399                 if (ret < 0)
1400                         return ret;
1401                 offset = 0;
1402                 len -= seg;
1403                 data += seg;
1404                 ++gfn;
1405         }
1406         return 0;
1407 }
1408
1409 int kvm_clear_guest_page(struct kvm *kvm, gfn_t gfn, int offset, int len)
1410 {
1411         return kvm_write_guest_page(kvm, gfn, empty_zero_page, offset, len);
1412 }
1413 EXPORT_SYMBOL_GPL(kvm_clear_guest_page);
1414
1415 int kvm_clear_guest(struct kvm *kvm, gpa_t gpa, unsigned long len)
1416 {
1417         gfn_t gfn = gpa >> PAGE_SHIFT;
1418         int seg;
1419         int offset = offset_in_page(gpa);
1420         int ret;
1421
1422         while ((seg = next_segment(len, offset)) != 0) {
1423                 ret = kvm_clear_guest_page(kvm, gfn, offset, seg);
1424                 if (ret < 0)
1425                         return ret;
1426                 offset = 0;
1427                 len -= seg;
1428                 ++gfn;
1429         }
1430         return 0;
1431 }
1432 EXPORT_SYMBOL_GPL(kvm_clear_guest);
1433
1434 void mark_page_dirty(struct kvm *kvm, gfn_t gfn)
1435 {
1436         struct kvm_memory_slot *memslot;
1437
1438         gfn = unalias_gfn(kvm, gfn);
1439         memslot = gfn_to_memslot_unaliased(kvm, gfn);
1440         if (memslot && memslot->dirty_bitmap) {
1441                 unsigned long rel_gfn = gfn - memslot->base_gfn;
1442
1443                 /* avoid RMW */
1444                 if (!test_bit(rel_gfn, memslot->dirty_bitmap))
1445                         set_bit(rel_gfn, memslot->dirty_bitmap);
1446         }
1447 }
1448
1449 /*
1450  * The vCPU has executed a HLT instruction with in-kernel mode enabled.
1451  */
1452 void kvm_vcpu_block(struct kvm_vcpu *vcpu)
1453 {
1454         DEFINE_WAIT(wait);
1455
1456         for (;;) {
1457                 prepare_to_wait(&vcpu->wq, &wait, TASK_INTERRUPTIBLE);
1458
1459                 if (kvm_cpu_has_interrupt(vcpu) ||
1460                     kvm_cpu_has_pending_timer(vcpu) ||
1461                     kvm_arch_vcpu_runnable(vcpu)) {
1462                         set_bit(KVM_REQ_UNHALT, &vcpu->requests);
1463                         break;
1464                 }
1465                 if (signal_pending(current))
1466                         break;
1467
1468                 vcpu_put(vcpu);
1469                 schedule();
1470                 vcpu_load(vcpu);
1471         }
1472
1473         finish_wait(&vcpu->wq, &wait);
1474 }
1475
1476 void kvm_resched(struct kvm_vcpu *vcpu)
1477 {
1478         if (!need_resched())
1479                 return;
1480         cond_resched();
1481 }
1482 EXPORT_SYMBOL_GPL(kvm_resched);
1483
1484 static int kvm_vcpu_fault(struct vm_area_struct *vma, struct vm_fault *vmf)
1485 {
1486         struct kvm_vcpu *vcpu = vma->vm_file->private_data;
1487         struct page *page;
1488
1489         if (vmf->pgoff == 0)
1490                 page = virt_to_page(vcpu->run);
1491 #ifdef CONFIG_X86
1492         else if (vmf->pgoff == KVM_PIO_PAGE_OFFSET)
1493                 page = virt_to_page(vcpu->arch.pio_data);
1494 #endif
1495 #ifdef KVM_COALESCED_MMIO_PAGE_OFFSET
1496         else if (vmf->pgoff == KVM_COALESCED_MMIO_PAGE_OFFSET)
1497                 page = virt_to_page(vcpu->kvm->coalesced_mmio_ring);
1498 #endif
1499         else
1500                 return VM_FAULT_SIGBUS;
1501         get_page(page);
1502         vmf->page = page;
1503         return 0;
1504 }
1505
1506 static struct vm_operations_struct kvm_vcpu_vm_ops = {
1507         .fault = kvm_vcpu_fault,
1508 };
1509
1510 static int kvm_vcpu_mmap(struct file *file, struct vm_area_struct *vma)
1511 {
1512         vma->vm_ops = &kvm_vcpu_vm_ops;
1513         return 0;
1514 }
1515
1516 static int kvm_vcpu_release(struct inode *inode, struct file *filp)
1517 {
1518         struct kvm_vcpu *vcpu = filp->private_data;
1519
1520         kvm_put_kvm(vcpu->kvm);
1521         return 0;
1522 }
1523
1524 static struct file_operations kvm_vcpu_fops = {
1525         .release        = kvm_vcpu_release,
1526         .unlocked_ioctl = kvm_vcpu_ioctl,
1527         .compat_ioctl   = kvm_vcpu_ioctl,
1528         .mmap           = kvm_vcpu_mmap,
1529 };
1530
1531 /*
1532  * Allocates an inode for the vcpu.
1533  */
1534 static int create_vcpu_fd(struct kvm_vcpu *vcpu)
1535 {
1536         int fd = anon_inode_getfd("kvm-vcpu", &kvm_vcpu_fops, vcpu, 0);
1537         if (fd < 0)
1538                 kvm_put_kvm(vcpu->kvm);
1539         return fd;
1540 }
1541
1542 /*
1543  * Creates some virtual cpus.  Good luck creating more than one.
1544  */
1545 static int kvm_vm_ioctl_create_vcpu(struct kvm *kvm, int n)
1546 {
1547         int r;
1548         struct kvm_vcpu *vcpu;
1549
1550         if (!valid_vcpu(n))
1551                 return -EINVAL;
1552
1553         vcpu = kvm_arch_vcpu_create(kvm, n);
1554         if (IS_ERR(vcpu))
1555                 return PTR_ERR(vcpu);
1556
1557         preempt_notifier_init(&vcpu->preempt_notifier, &kvm_preempt_ops);
1558
1559         r = kvm_arch_vcpu_setup(vcpu);
1560         if (r)
1561                 return r;
1562
1563         mutex_lock(&kvm->lock);
1564         if (kvm->vcpus[n]) {
1565                 r = -EEXIST;
1566                 goto vcpu_destroy;
1567         }
1568         kvm->vcpus[n] = vcpu;
1569         mutex_unlock(&kvm->lock);
1570
1571         /* Now it's all set up, let userspace reach it */
1572         kvm_get_kvm(kvm);
1573         r = create_vcpu_fd(vcpu);
1574         if (r < 0)
1575                 goto unlink;
1576         return r;
1577
1578 unlink:
1579         mutex_lock(&kvm->lock);
1580         kvm->vcpus[n] = NULL;
1581 vcpu_destroy:
1582         mutex_unlock(&kvm->lock);
1583         kvm_arch_vcpu_destroy(vcpu);
1584         return r;
1585 }
1586
1587 static int kvm_vcpu_ioctl_set_sigmask(struct kvm_vcpu *vcpu, sigset_t *sigset)
1588 {
1589         if (sigset) {
1590                 sigdelsetmask(sigset, sigmask(SIGKILL)|sigmask(SIGSTOP));
1591                 vcpu->sigset_active = 1;
1592                 vcpu->sigset = *sigset;
1593         } else
1594                 vcpu->sigset_active = 0;
1595         return 0;
1596 }
1597
1598 static long kvm_vcpu_ioctl(struct file *filp,
1599                            unsigned int ioctl, unsigned long arg)
1600 {
1601         struct kvm_vcpu *vcpu = filp->private_data;
1602         void __user *argp = (void __user *)arg;
1603         int r;
1604         struct kvm_fpu *fpu = NULL;
1605         struct kvm_sregs *kvm_sregs = NULL;
1606
1607         if (vcpu->kvm->mm != current->mm)
1608                 return -EIO;
1609         switch (ioctl) {
1610         case KVM_RUN:
1611                 r = -EINVAL;
1612                 if (arg)
1613                         goto out;
1614                 r = kvm_arch_vcpu_ioctl_run(vcpu, vcpu->run);
1615                 break;
1616         case KVM_GET_REGS: {
1617                 struct kvm_regs *kvm_regs;
1618
1619                 r = -ENOMEM;
1620                 kvm_regs = kzalloc(sizeof(struct kvm_regs), GFP_KERNEL);
1621                 if (!kvm_regs)
1622                         goto out;
1623                 r = kvm_arch_vcpu_ioctl_get_regs(vcpu, kvm_regs);
1624                 if (r)
1625                         goto out_free1;
1626                 r = -EFAULT;
1627                 if (copy_to_user(argp, kvm_regs, sizeof(struct kvm_regs)))
1628                         goto out_free1;
1629                 r = 0;
1630 out_free1:
1631                 kfree(kvm_regs);
1632                 break;
1633         }
1634         case KVM_SET_REGS: {
1635                 struct kvm_regs *kvm_regs;
1636
1637                 r = -ENOMEM;
1638                 kvm_regs = kzalloc(sizeof(struct kvm_regs), GFP_KERNEL);
1639                 if (!kvm_regs)
1640                         goto out;
1641                 r = -EFAULT;
1642                 if (copy_from_user(kvm_regs, argp, sizeof(struct kvm_regs)))
1643                         goto out_free2;
1644                 r = kvm_arch_vcpu_ioctl_set_regs(vcpu, kvm_regs);
1645                 if (r)
1646                         goto out_free2;
1647                 r = 0;
1648 out_free2:
1649                 kfree(kvm_regs);
1650                 break;
1651         }
1652         case KVM_GET_SREGS: {
1653                 kvm_sregs = kzalloc(sizeof(struct kvm_sregs), GFP_KERNEL);
1654                 r = -ENOMEM;
1655                 if (!kvm_sregs)
1656                         goto out;
1657                 r = kvm_arch_vcpu_ioctl_get_sregs(vcpu, kvm_sregs);
1658                 if (r)
1659                         goto out;
1660                 r = -EFAULT;
1661                 if (copy_to_user(argp, kvm_sregs, sizeof(struct kvm_sregs)))
1662                         goto out;
1663                 r = 0;
1664                 break;
1665         }
1666         case KVM_SET_SREGS: {
1667                 kvm_sregs = kmalloc(sizeof(struct kvm_sregs), GFP_KERNEL);
1668                 r = -ENOMEM;
1669                 if (!kvm_sregs)
1670                         goto out;
1671                 r = -EFAULT;
1672                 if (copy_from_user(kvm_sregs, argp, sizeof(struct kvm_sregs)))
1673                         goto out;
1674                 r = kvm_arch_vcpu_ioctl_set_sregs(vcpu, kvm_sregs);
1675                 if (r)
1676                         goto out;
1677                 r = 0;
1678                 break;
1679         }
1680         case KVM_GET_MP_STATE: {
1681                 struct kvm_mp_state mp_state;
1682
1683                 r = kvm_arch_vcpu_ioctl_get_mpstate(vcpu, &mp_state);
1684                 if (r)
1685                         goto out;
1686                 r = -EFAULT;
1687                 if (copy_to_user(argp, &mp_state, sizeof mp_state))
1688                         goto out;
1689                 r = 0;
1690                 break;
1691         }
1692         case KVM_SET_MP_STATE: {
1693                 struct kvm_mp_state mp_state;
1694
1695                 r = -EFAULT;
1696                 if (copy_from_user(&mp_state, argp, sizeof mp_state))
1697                         goto out;
1698                 r = kvm_arch_vcpu_ioctl_set_mpstate(vcpu, &mp_state);
1699                 if (r)
1700                         goto out;
1701                 r = 0;
1702                 break;
1703         }
1704         case KVM_TRANSLATE: {
1705                 struct kvm_translation tr;
1706
1707                 r = -EFAULT;
1708                 if (copy_from_user(&tr, argp, sizeof tr))
1709                         goto out;
1710                 r = kvm_arch_vcpu_ioctl_translate(vcpu, &tr);
1711                 if (r)
1712                         goto out;
1713                 r = -EFAULT;
1714                 if (copy_to_user(argp, &tr, sizeof tr))
1715                         goto out;
1716                 r = 0;
1717                 break;
1718         }
1719         case KVM_SET_GUEST_DEBUG: {
1720                 struct kvm_guest_debug dbg;
1721
1722                 r = -EFAULT;
1723                 if (copy_from_user(&dbg, argp, sizeof dbg))
1724                         goto out;
1725                 r = kvm_arch_vcpu_ioctl_set_guest_debug(vcpu, &dbg);
1726                 if (r)
1727                         goto out;
1728                 r = 0;
1729                 break;
1730         }
1731         case KVM_SET_SIGNAL_MASK: {
1732                 struct kvm_signal_mask __user *sigmask_arg = argp;
1733                 struct kvm_signal_mask kvm_sigmask;
1734                 sigset_t sigset, *p;
1735
1736                 p = NULL;
1737                 if (argp) {
1738                         r = -EFAULT;
1739                         if (copy_from_user(&kvm_sigmask, argp,
1740                                            sizeof kvm_sigmask))
1741                                 goto out;
1742                         r = -EINVAL;
1743                         if (kvm_sigmask.len != sizeof sigset)
1744                                 goto out;
1745                         r = -EFAULT;
1746                         if (copy_from_user(&sigset, sigmask_arg->sigset,
1747                                            sizeof sigset))
1748                                 goto out;
1749                         p = &sigset;
1750                 }
1751                 r = kvm_vcpu_ioctl_set_sigmask(vcpu, &sigset);
1752                 break;
1753         }
1754         case KVM_GET_FPU: {
1755                 fpu = kzalloc(sizeof(struct kvm_fpu), GFP_KERNEL);
1756                 r = -ENOMEM;
1757                 if (!fpu)
1758                         goto out;
1759                 r = kvm_arch_vcpu_ioctl_get_fpu(vcpu, fpu);
1760                 if (r)
1761                         goto out;
1762                 r = -EFAULT;
1763                 if (copy_to_user(argp, fpu, sizeof(struct kvm_fpu)))
1764                         goto out;
1765                 r = 0;
1766                 break;
1767         }
1768         case KVM_SET_FPU: {
1769                 fpu = kmalloc(sizeof(struct kvm_fpu), GFP_KERNEL);
1770                 r = -ENOMEM;
1771                 if (!fpu)
1772                         goto out;
1773                 r = -EFAULT;
1774                 if (copy_from_user(fpu, argp, sizeof(struct kvm_fpu)))
1775                         goto out;
1776                 r = kvm_arch_vcpu_ioctl_set_fpu(vcpu, fpu);
1777                 if (r)
1778                         goto out;
1779                 r = 0;
1780                 break;
1781         }
1782         default:
1783                 r = kvm_arch_vcpu_ioctl(filp, ioctl, arg);
1784         }
1785 out:
1786         kfree(fpu);
1787         kfree(kvm_sregs);
1788         return r;
1789 }
1790
1791 static long kvm_vm_ioctl(struct file *filp,
1792                            unsigned int ioctl, unsigned long arg)
1793 {
1794         struct kvm *kvm = filp->private_data;
1795         void __user *argp = (void __user *)arg;
1796         int r;
1797
1798         if (kvm->mm != current->mm)
1799                 return -EIO;
1800         switch (ioctl) {
1801         case KVM_CREATE_VCPU:
1802                 r = kvm_vm_ioctl_create_vcpu(kvm, arg);
1803                 if (r < 0)
1804                         goto out;
1805                 break;
1806         case KVM_SET_USER_MEMORY_REGION: {
1807                 struct kvm_userspace_memory_region kvm_userspace_mem;
1808
1809                 r = -EFAULT;
1810                 if (copy_from_user(&kvm_userspace_mem, argp,
1811                                                 sizeof kvm_userspace_mem))
1812                         goto out;
1813
1814                 r = kvm_vm_ioctl_set_memory_region(kvm, &kvm_userspace_mem, 1);
1815                 if (r)
1816                         goto out;
1817                 break;
1818         }
1819         case KVM_GET_DIRTY_LOG: {
1820                 struct kvm_dirty_log log;
1821
1822                 r = -EFAULT;
1823                 if (copy_from_user(&log, argp, sizeof log))
1824                         goto out;
1825                 r = kvm_vm_ioctl_get_dirty_log(kvm, &log);
1826                 if (r)
1827                         goto out;
1828                 break;
1829         }
1830 #ifdef KVM_COALESCED_MMIO_PAGE_OFFSET
1831         case KVM_REGISTER_COALESCED_MMIO: {
1832                 struct kvm_coalesced_mmio_zone zone;
1833                 r = -EFAULT;
1834                 if (copy_from_user(&zone, argp, sizeof zone))
1835                         goto out;
1836                 r = -ENXIO;
1837                 r = kvm_vm_ioctl_register_coalesced_mmio(kvm, &zone);
1838                 if (r)
1839                         goto out;
1840                 r = 0;
1841                 break;
1842         }
1843         case KVM_UNREGISTER_COALESCED_MMIO: {
1844                 struct kvm_coalesced_mmio_zone zone;
1845                 r = -EFAULT;
1846                 if (copy_from_user(&zone, argp, sizeof zone))
1847                         goto out;
1848                 r = -ENXIO;
1849                 r = kvm_vm_ioctl_unregister_coalesced_mmio(kvm, &zone);
1850                 if (r)
1851                         goto out;
1852                 r = 0;
1853                 break;
1854         }
1855 #endif
1856 #ifdef KVM_CAP_DEVICE_ASSIGNMENT
1857         case KVM_ASSIGN_PCI_DEVICE: {
1858                 struct kvm_assigned_pci_dev assigned_dev;
1859
1860                 r = -EFAULT;
1861                 if (copy_from_user(&assigned_dev, argp, sizeof assigned_dev))
1862                         goto out;
1863                 r = kvm_vm_ioctl_assign_device(kvm, &assigned_dev);
1864                 if (r)
1865                         goto out;
1866                 break;
1867         }
1868         case KVM_ASSIGN_IRQ: {
1869                 struct kvm_assigned_irq assigned_irq;
1870
1871                 r = -EFAULT;
1872                 if (copy_from_user(&assigned_irq, argp, sizeof assigned_irq))
1873                         goto out;
1874                 r = kvm_vm_ioctl_assign_irq(kvm, &assigned_irq);
1875                 if (r)
1876                         goto out;
1877                 break;
1878         }
1879 #endif
1880 #ifdef KVM_CAP_DEVICE_DEASSIGNMENT
1881         case KVM_DEASSIGN_PCI_DEVICE: {
1882                 struct kvm_assigned_pci_dev assigned_dev;
1883
1884                 r = -EFAULT;
1885                 if (copy_from_user(&assigned_dev, argp, sizeof assigned_dev))
1886                         goto out;
1887                 r = kvm_vm_ioctl_deassign_device(kvm, &assigned_dev);
1888                 if (r)
1889                         goto out;
1890                 break;
1891         }
1892 #endif
1893 #ifdef KVM_CAP_IRQ_ROUTING
1894         case KVM_SET_GSI_ROUTING: {
1895                 struct kvm_irq_routing routing;
1896                 struct kvm_irq_routing __user *urouting;
1897                 struct kvm_irq_routing_entry *entries;
1898
1899                 r = -EFAULT;
1900                 if (copy_from_user(&routing, argp, sizeof(routing)))
1901                         goto out;
1902                 r = -EINVAL;
1903                 if (routing.nr >= KVM_MAX_IRQ_ROUTES)
1904                         goto out;
1905                 if (routing.flags)
1906                         goto out;
1907                 r = -ENOMEM;
1908                 entries = vmalloc(routing.nr * sizeof(*entries));
1909                 if (!entries)
1910                         goto out;
1911                 r = -EFAULT;
1912                 urouting = argp;
1913                 if (copy_from_user(entries, urouting->entries,
1914                                    routing.nr * sizeof(*entries)))
1915                         goto out_free_irq_routing;
1916                 r = kvm_set_irq_routing(kvm, entries, routing.nr,
1917                                         routing.flags);
1918         out_free_irq_routing:
1919                 vfree(entries);
1920                 break;
1921         }
1922 #endif
1923         default:
1924                 r = kvm_arch_vm_ioctl(filp, ioctl, arg);
1925         }
1926 out:
1927         return r;
1928 }
1929
1930 static int kvm_vm_fault(struct vm_area_struct *vma, struct vm_fault *vmf)
1931 {
1932         struct page *page[1];
1933         unsigned long addr;
1934         int npages;
1935         gfn_t gfn = vmf->pgoff;
1936         struct kvm *kvm = vma->vm_file->private_data;
1937
1938         addr = gfn_to_hva(kvm, gfn);
1939         if (kvm_is_error_hva(addr))
1940                 return VM_FAULT_SIGBUS;
1941
1942         npages = get_user_pages(current, current->mm, addr, 1, 1, 0, page,
1943                                 NULL);
1944         if (unlikely(npages != 1))
1945                 return VM_FAULT_SIGBUS;
1946
1947         vmf->page = page[0];
1948         return 0;
1949 }
1950
1951 static struct vm_operations_struct kvm_vm_vm_ops = {
1952         .fault = kvm_vm_fault,
1953 };
1954
1955 static int kvm_vm_mmap(struct file *file, struct vm_area_struct *vma)
1956 {
1957         vma->vm_ops = &kvm_vm_vm_ops;
1958         return 0;
1959 }
1960
1961 static struct file_operations kvm_vm_fops = {
1962         .release        = kvm_vm_release,
1963         .unlocked_ioctl = kvm_vm_ioctl,
1964         .compat_ioctl   = kvm_vm_ioctl,
1965         .mmap           = kvm_vm_mmap,
1966 };
1967
1968 static int kvm_dev_ioctl_create_vm(void)
1969 {
1970         int fd;
1971         struct kvm *kvm;
1972
1973         kvm = kvm_create_vm();
1974         if (IS_ERR(kvm))
1975                 return PTR_ERR(kvm);
1976         fd = anon_inode_getfd("kvm-vm", &kvm_vm_fops, kvm, 0);
1977         if (fd < 0)
1978                 kvm_put_kvm(kvm);
1979
1980         return fd;
1981 }
1982
1983 static long kvm_dev_ioctl_check_extension_generic(long arg)
1984 {
1985         switch (arg) {
1986         case KVM_CAP_USER_MEMORY:
1987         case KVM_CAP_DESTROY_MEMORY_REGION_WORKS:
1988                 return 1;
1989 #ifdef CONFIG_HAVE_KVM_IRQCHIP
1990         case KVM_CAP_IRQ_ROUTING:
1991                 return KVM_MAX_IRQ_ROUTES;
1992 #endif
1993         default:
1994                 break;
1995         }
1996         return kvm_dev_ioctl_check_extension(arg);
1997 }
1998
1999 static long kvm_dev_ioctl(struct file *filp,
2000                           unsigned int ioctl, unsigned long arg)
2001 {
2002         long r = -EINVAL;
2003
2004         switch (ioctl) {
2005         case KVM_GET_API_VERSION:
2006                 r = -EINVAL;
2007                 if (arg)
2008                         goto out;
2009                 r = KVM_API_VERSION;
2010                 break;
2011         case KVM_CREATE_VM:
2012                 r = -EINVAL;
2013                 if (arg)
2014                         goto out;
2015                 r = kvm_dev_ioctl_create_vm();
2016                 break;
2017         case KVM_CHECK_EXTENSION:
2018                 r = kvm_dev_ioctl_check_extension_generic(arg);
2019                 break;
2020         case KVM_GET_VCPU_MMAP_SIZE:
2021                 r = -EINVAL;
2022                 if (arg)
2023                         goto out;
2024                 r = PAGE_SIZE;     /* struct kvm_run */
2025 #ifdef CONFIG_X86
2026                 r += PAGE_SIZE;    /* pio data page */
2027 #endif
2028 #ifdef KVM_COALESCED_MMIO_PAGE_OFFSET
2029                 r += PAGE_SIZE;    /* coalesced mmio ring page */
2030 #endif
2031                 break;
2032         case KVM_TRACE_ENABLE:
2033         case KVM_TRACE_PAUSE:
2034         case KVM_TRACE_DISABLE:
2035                 r = kvm_trace_ioctl(ioctl, arg);
2036                 break;
2037         default:
2038                 return kvm_arch_dev_ioctl(filp, ioctl, arg);
2039         }
2040 out:
2041         return r;
2042 }
2043
2044 static struct file_operations kvm_chardev_ops = {
2045         .unlocked_ioctl = kvm_dev_ioctl,
2046         .compat_ioctl   = kvm_dev_ioctl,
2047 };
2048
2049 static struct miscdevice kvm_dev = {
2050         KVM_MINOR,
2051         "kvm",
2052         &kvm_chardev_ops,
2053 };
2054
2055 static void hardware_enable(void *junk)
2056 {
2057         int cpu = raw_smp_processor_id();
2058
2059         if (cpumask_test_cpu(cpu, cpus_hardware_enabled))
2060                 return;
2061         cpumask_set_cpu(cpu, cpus_hardware_enabled);
2062         kvm_arch_hardware_enable(NULL);
2063 }
2064
2065 static void hardware_disable(void *junk)
2066 {
2067         int cpu = raw_smp_processor_id();
2068
2069         if (!cpumask_test_cpu(cpu, cpus_hardware_enabled))
2070                 return;
2071         cpumask_clear_cpu(cpu, cpus_hardware_enabled);
2072         kvm_arch_hardware_disable(NULL);
2073 }
2074
2075 static int kvm_cpu_hotplug(struct notifier_block *notifier, unsigned long val,
2076                            void *v)
2077 {
2078         int cpu = (long)v;
2079
2080         val &= ~CPU_TASKS_FROZEN;
2081         switch (val) {
2082         case CPU_DYING:
2083                 printk(KERN_INFO "kvm: disabling virtualization on CPU%d\n",
2084                        cpu);
2085                 hardware_disable(NULL);
2086                 break;
2087         case CPU_UP_CANCELED:
2088                 printk(KERN_INFO "kvm: disabling virtualization on CPU%d\n",
2089                        cpu);
2090                 smp_call_function_single(cpu, hardware_disable, NULL, 1);
2091                 break;
2092         case CPU_ONLINE:
2093                 printk(KERN_INFO "kvm: enabling virtualization on CPU%d\n",
2094                        cpu);
2095                 smp_call_function_single(cpu, hardware_enable, NULL, 1);
2096                 break;
2097         }
2098         return NOTIFY_OK;
2099 }
2100
2101
2102 asmlinkage void kvm_handle_fault_on_reboot(void)
2103 {
2104         if (kvm_rebooting)
2105                 /* spin while reset goes on */
2106                 while (true)
2107                         ;
2108         /* Fault while not rebooting.  We want the trace. */
2109         BUG();
2110 }
2111 EXPORT_SYMBOL_GPL(kvm_handle_fault_on_reboot);
2112
2113 static int kvm_reboot(struct notifier_block *notifier, unsigned long val,
2114                       void *v)
2115 {
2116         if (val == SYS_RESTART) {
2117                 /*
2118                  * Some (well, at least mine) BIOSes hang on reboot if
2119                  * in vmx root mode.
2120                  */
2121                 printk(KERN_INFO "kvm: exiting hardware virtualization\n");
2122                 kvm_rebooting = true;
2123                 on_each_cpu(hardware_disable, NULL, 1);
2124         }
2125         return NOTIFY_OK;
2126 }
2127
2128 static struct notifier_block kvm_reboot_notifier = {
2129         .notifier_call = kvm_reboot,
2130         .priority = 0,
2131 };
2132
2133 void kvm_io_bus_init(struct kvm_io_bus *bus)
2134 {
2135         memset(bus, 0, sizeof(*bus));
2136 }
2137
2138 void kvm_io_bus_destroy(struct kvm_io_bus *bus)
2139 {
2140         int i;
2141
2142         for (i = 0; i < bus->dev_count; i++) {
2143                 struct kvm_io_device *pos = bus->devs[i];
2144
2145                 kvm_iodevice_destructor(pos);
2146         }
2147 }
2148
2149 struct kvm_io_device *kvm_io_bus_find_dev(struct kvm_io_bus *bus,
2150                                           gpa_t addr, int len, int is_write)
2151 {
2152         int i;
2153
2154         for (i = 0; i < bus->dev_count; i++) {
2155                 struct kvm_io_device *pos = bus->devs[i];
2156
2157                 if (pos->in_range(pos, addr, len, is_write))
2158                         return pos;
2159         }
2160
2161         return NULL;
2162 }
2163
2164 void kvm_io_bus_register_dev(struct kvm_io_bus *bus, struct kvm_io_device *dev)
2165 {
2166         BUG_ON(bus->dev_count > (NR_IOBUS_DEVS-1));
2167
2168         bus->devs[bus->dev_count++] = dev;
2169 }
2170
2171 static struct notifier_block kvm_cpu_notifier = {
2172         .notifier_call = kvm_cpu_hotplug,
2173         .priority = 20, /* must be > scheduler priority */
2174 };
2175
2176 static int vm_stat_get(void *_offset, u64 *val)
2177 {
2178         unsigned offset = (long)_offset;
2179         struct kvm *kvm;
2180
2181         *val = 0;
2182         spin_lock(&kvm_lock);
2183         list_for_each_entry(kvm, &vm_list, vm_list)
2184                 *val += *(u32 *)((void *)kvm + offset);
2185         spin_unlock(&kvm_lock);
2186         return 0;
2187 }
2188
2189 DEFINE_SIMPLE_ATTRIBUTE(vm_stat_fops, vm_stat_get, NULL, "%llu\n");
2190
2191 static int vcpu_stat_get(void *_offset, u64 *val)
2192 {
2193         unsigned offset = (long)_offset;
2194         struct kvm *kvm;
2195         struct kvm_vcpu *vcpu;
2196         int i;
2197
2198         *val = 0;
2199         spin_lock(&kvm_lock);
2200         list_for_each_entry(kvm, &vm_list, vm_list)
2201                 for (i = 0; i < KVM_MAX_VCPUS; ++i) {
2202                         vcpu = kvm->vcpus[i];
2203                         if (vcpu)
2204                                 *val += *(u32 *)((void *)vcpu + offset);
2205                 }
2206         spin_unlock(&kvm_lock);
2207         return 0;
2208 }
2209
2210 DEFINE_SIMPLE_ATTRIBUTE(vcpu_stat_fops, vcpu_stat_get, NULL, "%llu\n");
2211
2212 static struct file_operations *stat_fops[] = {
2213         [KVM_STAT_VCPU] = &vcpu_stat_fops,
2214         [KVM_STAT_VM]   = &vm_stat_fops,
2215 };
2216
2217 static void kvm_init_debug(void)
2218 {
2219         struct kvm_stats_debugfs_item *p;
2220
2221         kvm_debugfs_dir = debugfs_create_dir("kvm", NULL);
2222         for (p = debugfs_entries; p->name; ++p)
2223                 p->dentry = debugfs_create_file(p->name, 0444, kvm_debugfs_dir,
2224                                                 (void *)(long)p->offset,
2225                                                 stat_fops[p->kind]);
2226 }
2227
2228 static void kvm_exit_debug(void)
2229 {
2230         struct kvm_stats_debugfs_item *p;
2231
2232         for (p = debugfs_entries; p->name; ++p)
2233                 debugfs_remove(p->dentry);
2234         debugfs_remove(kvm_debugfs_dir);
2235 }
2236
2237 static int kvm_suspend(struct sys_device *dev, pm_message_t state)
2238 {
2239         hardware_disable(NULL);
2240         return 0;
2241 }
2242
2243 static int kvm_resume(struct sys_device *dev)
2244 {
2245         hardware_enable(NULL);
2246         return 0;
2247 }
2248
2249 static struct sysdev_class kvm_sysdev_class = {
2250         .name = "kvm",
2251         .suspend = kvm_suspend,
2252         .resume = kvm_resume,
2253 };
2254
2255 static struct sys_device kvm_sysdev = {
2256         .id = 0,
2257         .cls = &kvm_sysdev_class,
2258 };
2259
2260 struct page *bad_page;
2261 pfn_t bad_pfn;
2262
2263 static inline
2264 struct kvm_vcpu *preempt_notifier_to_vcpu(struct preempt_notifier *pn)
2265 {
2266         return container_of(pn, struct kvm_vcpu, preempt_notifier);
2267 }
2268
2269 static void kvm_sched_in(struct preempt_notifier *pn, int cpu)
2270 {
2271         struct kvm_vcpu *vcpu = preempt_notifier_to_vcpu(pn);
2272
2273         kvm_arch_vcpu_load(vcpu, cpu);
2274 }
2275
2276 static void kvm_sched_out(struct preempt_notifier *pn,
2277                           struct task_struct *next)
2278 {
2279         struct kvm_vcpu *vcpu = preempt_notifier_to_vcpu(pn);
2280
2281         kvm_arch_vcpu_put(vcpu);
2282 }
2283
2284 int kvm_init(void *opaque, unsigned int vcpu_size,
2285                   struct module *module)
2286 {
2287         int r;
2288         int cpu;
2289
2290         kvm_init_debug();
2291
2292         r = kvm_arch_init(opaque);
2293         if (r)
2294                 goto out_fail;
2295
2296         bad_page = alloc_page(GFP_KERNEL | __GFP_ZERO);
2297
2298         if (bad_page == NULL) {
2299                 r = -ENOMEM;
2300                 goto out;
2301         }
2302
2303         bad_pfn = page_to_pfn(bad_page);
2304
2305         if (!alloc_cpumask_var(&cpus_hardware_enabled, GFP_KERNEL)) {
2306                 r = -ENOMEM;
2307                 goto out_free_0;
2308         }
2309
2310         r = kvm_arch_hardware_setup();
2311         if (r < 0)
2312                 goto out_free_0a;
2313
2314         for_each_online_cpu(cpu) {
2315                 smp_call_function_single(cpu,
2316                                 kvm_arch_check_processor_compat,
2317                                 &r, 1);
2318                 if (r < 0)
2319                         goto out_free_1;
2320         }
2321
2322         on_each_cpu(hardware_enable, NULL, 1);
2323         r = register_cpu_notifier(&kvm_cpu_notifier);
2324         if (r)
2325                 goto out_free_2;
2326         register_reboot_notifier(&kvm_reboot_notifier);
2327
2328         r = sysdev_class_register(&kvm_sysdev_class);
2329         if (r)
2330                 goto out_free_3;
2331
2332         r = sysdev_register(&kvm_sysdev);
2333         if (r)
2334                 goto out_free_4;
2335
2336         /* A kmem cache lets us meet the alignment requirements of fx_save. */
2337         kvm_vcpu_cache = kmem_cache_create("kvm_vcpu", vcpu_size,
2338                                            __alignof__(struct kvm_vcpu),
2339                                            0, NULL);
2340         if (!kvm_vcpu_cache) {
2341                 r = -ENOMEM;
2342                 goto out_free_5;
2343         }
2344
2345         kvm_chardev_ops.owner = module;
2346         kvm_vm_fops.owner = module;
2347         kvm_vcpu_fops.owner = module;
2348
2349         r = misc_register(&kvm_dev);
2350         if (r) {
2351                 printk(KERN_ERR "kvm: misc device register failed\n");
2352                 goto out_free;
2353         }
2354
2355         kvm_preempt_ops.sched_in = kvm_sched_in;
2356         kvm_preempt_ops.sched_out = kvm_sched_out;
2357 #ifndef CONFIG_X86
2358         msi2intx = 0;
2359 #endif
2360
2361         return 0;
2362
2363 out_free:
2364         kmem_cache_destroy(kvm_vcpu_cache);
2365 out_free_5:
2366         sysdev_unregister(&kvm_sysdev);
2367 out_free_4:
2368         sysdev_class_unregister(&kvm_sysdev_class);
2369 out_free_3:
2370         unregister_reboot_notifier(&kvm_reboot_notifier);
2371         unregister_cpu_notifier(&kvm_cpu_notifier);
2372 out_free_2:
2373         on_each_cpu(hardware_disable, NULL, 1);
2374 out_free_1:
2375         kvm_arch_hardware_unsetup();
2376 out_free_0a:
2377         free_cpumask_var(cpus_hardware_enabled);
2378 out_free_0:
2379         __free_page(bad_page);
2380 out:
2381         kvm_arch_exit();
2382         kvm_exit_debug();
2383 out_fail:
2384         return r;
2385 }
2386 EXPORT_SYMBOL_GPL(kvm_init);
2387
2388 void kvm_exit(void)
2389 {
2390         kvm_trace_cleanup();
2391         misc_deregister(&kvm_dev);
2392         kmem_cache_destroy(kvm_vcpu_cache);
2393         sysdev_unregister(&kvm_sysdev);
2394         sysdev_class_unregister(&kvm_sysdev_class);
2395         unregister_reboot_notifier(&kvm_reboot_notifier);
2396         unregister_cpu_notifier(&kvm_cpu_notifier);
2397         on_each_cpu(hardware_disable, NULL, 1);
2398         kvm_arch_hardware_unsetup();
2399         kvm_arch_exit();
2400         kvm_exit_debug();
2401         free_cpumask_var(cpus_hardware_enabled);
2402         __free_page(bad_page);
2403 }
2404 EXPORT_SYMBOL_GPL(kvm_exit);