Pileus Git - ~andy/linux/blob - virt/kvm/assigned-dev.c

   1 /*
   2  * Kernel-based Virtual Machine - device assignment support
   3  *
   4  * Copyright (C) 2010 Red Hat, Inc. and/or its affiliates.
   5  *
   6  * This work is licensed under the terms of the GNU GPL, version 2.  See
   7  * the COPYING file in the top-level directory.
   8  *
   9  */
  10
  11 #include <linux/kvm_host.h>
  12 #include <linux/kvm.h>
  13 #include <linux/uaccess.h>
  14 #include <linux/vmalloc.h>
  15 #include <linux/errno.h>
  16 #include <linux/spinlock.h>
  17 #include <linux/pci.h>
  18 #include <linux/interrupt.h>
  19 #include <linux/slab.h>
  20 #include <linux/namei.h>
  21 #include <linux/fs.h>
  22 #include "irq.h"
  23
  24 static struct kvm_assigned_dev_kernel *kvm_find_assigned_dev(struct list_head *head,
  25                                                       int assigned_dev_id)
  26 {
  27         struct list_head *ptr;
  28         struct kvm_assigned_dev_kernel *match;
  29
  30         list_for_each(ptr, head) {
  31                 match = list_entry(ptr, struct kvm_assigned_dev_kernel, list);
  32                 if (match->assigned_dev_id == assigned_dev_id)
  33                         return match;
  34         }
  35         return NULL;
  36 }
  37
  38 static int find_index_from_host_irq(struct kvm_assigned_dev_kernel
  39                                     *assigned_dev, int irq)
  40 {
  41         int i, index;
  42         struct msix_entry *host_msix_entries;
  43
  44         host_msix_entries = assigned_dev->host_msix_entries;
  45
  46         index = -1;
  47         for (i = 0; i < assigned_dev->entries_nr; i++)
  48                 if (irq == host_msix_entries[i].vector) {
  49                         index = i;
  50                         break;
  51                 }
  52         if (index < 0)
  53                 printk(KERN_WARNING "Fail to find correlated MSI-X entry!\n");
  54
  55         return index;
  56 }
  57
  58 static irqreturn_t kvm_assigned_dev_intx(int irq, void *dev_id)
  59 {
  60         struct kvm_assigned_dev_kernel *assigned_dev = dev_id;
  61         int ret;
  62
  63         spin_lock(&assigned_dev->intx_lock);
  64         if (pci_check_and_mask_intx(assigned_dev->dev)) {
  65                 assigned_dev->host_irq_disabled = true;
  66                 ret = IRQ_WAKE_THREAD;
  67         } else
  68                 ret = IRQ_NONE;
  69         spin_unlock(&assigned_dev->intx_lock);
  70
  71         return ret;
  72 }
  73
  74 static void
  75 kvm_assigned_dev_raise_guest_irq(struct kvm_assigned_dev_kernel *assigned_dev,
  76                                  int vector)
  77 {
  78         if (unlikely(assigned_dev->irq_requested_type &
  79                      KVM_DEV_IRQ_GUEST_INTX)) {
  80                 spin_lock(&assigned_dev->intx_mask_lock);
  81                 if (!(assigned_dev->flags & KVM_DEV_ASSIGN_MASK_INTX))
  82                         kvm_set_irq(assigned_dev->kvm,
  83                                     assigned_dev->irq_source_id, vector, 1);
  84                 spin_unlock(&assigned_dev->intx_mask_lock);
  85         } else
  86                 kvm_set_irq(assigned_dev->kvm, assigned_dev->irq_source_id,
  87                             vector, 1);
  88 }
  89
  90 static irqreturn_t kvm_assigned_dev_thread_intx(int irq, void *dev_id)
  91 {
  92         struct kvm_assigned_dev_kernel *assigned_dev = dev_id;
  93
  94         if (!(assigned_dev->flags & KVM_DEV_ASSIGN_PCI_2_3)) {
  95                 spin_lock_irq(&assigned_dev->intx_lock);
  96                 disable_irq_nosync(irq);
  97                 assigned_dev->host_irq_disabled = true;
  98                 spin_unlock_irq(&assigned_dev->intx_lock);
  99         }
 100
 101         kvm_assigned_dev_raise_guest_irq(assigned_dev,
 102                                          assigned_dev->guest_irq);
 103
 104         return IRQ_HANDLED;
 105 }
 106
 107 #ifdef __KVM_HAVE_MSI
 108 static irqreturn_t kvm_assigned_dev_thread_msi(int irq, void *dev_id)
 109 {
 110         struct kvm_assigned_dev_kernel *assigned_dev = dev_id;
 111
 112         kvm_assigned_dev_raise_guest_irq(assigned_dev,
 113                                          assigned_dev->guest_irq);
 114
 115         return IRQ_HANDLED;
 116 }
 117 #endif
 118
 119 #ifdef __KVM_HAVE_MSIX
 120 static irqreturn_t kvm_assigned_dev_thread_msix(int irq, void *dev_id)
 121 {
 122         struct kvm_assigned_dev_kernel *assigned_dev = dev_id;
 123         int index = find_index_from_host_irq(assigned_dev, irq);
 124         u32 vector;
 125
 126         if (index >= 0) {
 127                 vector = assigned_dev->guest_msix_entries[index].vector;
 128                 kvm_assigned_dev_raise_guest_irq(assigned_dev, vector);
 129         }
 130
 131         return IRQ_HANDLED;
 132 }
 133 #endif
 134
 135 /* Ack the irq line for an assigned device */
 136 static void kvm_assigned_dev_ack_irq(struct kvm_irq_ack_notifier *kian)
 137 {
 138         struct kvm_assigned_dev_kernel *dev =
 139                 container_of(kian, struct kvm_assigned_dev_kernel,
 140                              ack_notifier);
 141
 142         kvm_set_irq(dev->kvm, dev->irq_source_id, dev->guest_irq, 0);
 143
 144         spin_lock(&dev->intx_mask_lock);
 145
 146         if (!(dev->flags & KVM_DEV_ASSIGN_MASK_INTX)) {
 147                 bool reassert = false;
 148
 149                 spin_lock_irq(&dev->intx_lock);
 150                 /*
 151                  * The guest IRQ may be shared so this ack can come from an
 152                  * IRQ for another guest device.
 153                  */
 154                 if (dev->host_irq_disabled) {
 155                         if (!(dev->flags & KVM_DEV_ASSIGN_PCI_2_3))
 156                                 enable_irq(dev->host_irq);
 157                         else if (!pci_check_and_unmask_intx(dev->dev))
 158                                 reassert = true;
 159                         dev->host_irq_disabled = reassert;
 160                 }
 161                 spin_unlock_irq(&dev->intx_lock);
 162
 163                 if (reassert)
 164                         kvm_set_irq(dev->kvm, dev->irq_source_id,
 165                                     dev->guest_irq, 1);
 166         }
 167
 168         spin_unlock(&dev->intx_mask_lock);
 169 }
 170
 171 static void deassign_guest_irq(struct kvm *kvm,
 172                                struct kvm_assigned_dev_kernel *assigned_dev)
 173 {
 174         if (assigned_dev->ack_notifier.gsi != -1)
 175                 kvm_unregister_irq_ack_notifier(kvm,
 176                                                 &assigned_dev->ack_notifier);
 177
 178         kvm_set_irq(assigned_dev->kvm, assigned_dev->irq_source_id,
 179                     assigned_dev->guest_irq, 0);
 180
 181         if (assigned_dev->irq_source_id != -1)
 182                 kvm_free_irq_source_id(kvm, assigned_dev->irq_source_id);
 183         assigned_dev->irq_source_id = -1;
 184         assigned_dev->irq_requested_type &= ~(KVM_DEV_IRQ_GUEST_MASK);
 185 }
 186
 187 /* The function implicit hold kvm->lock mutex due to cancel_work_sync() */
 188 static void deassign_host_irq(struct kvm *kvm,
 189                               struct kvm_assigned_dev_kernel *assigned_dev)
 190 {
 191         /*
 192          * We disable irq here to prevent further events.
 193          *
 194          * Notice this maybe result in nested disable if the interrupt type is
 195          * INTx, but it's OK for we are going to free it.
 196          *
 197          * If this function is a part of VM destroy, please ensure that till
 198          * now, the kvm state is still legal for probably we also have to wait
 199          * on a currently running IRQ handler.
 200          */
 201         if (assigned_dev->irq_requested_type & KVM_DEV_IRQ_HOST_MSIX) {
 202                 int i;
 203                 for (i = 0; i < assigned_dev->entries_nr; i++)
 204                         disable_irq(assigned_dev->host_msix_entries[i].vector);
 205
 206                 for (i = 0; i < assigned_dev->entries_nr; i++)
 207                         free_irq(assigned_dev->host_msix_entries[i].vector,
 208                                  assigned_dev);
 209
 210                 assigned_dev->entries_nr = 0;
 211                 kfree(assigned_dev->host_msix_entries);
 212                 kfree(assigned_dev->guest_msix_entries);
 213                 pci_disable_msix(assigned_dev->dev);
 214         } else {
 215                 /* Deal with MSI and INTx */
 216                 if ((assigned_dev->irq_requested_type &
 217                      KVM_DEV_IRQ_HOST_INTX) &&
 218                     (assigned_dev->flags & KVM_DEV_ASSIGN_PCI_2_3)) {
 219                         spin_lock_irq(&assigned_dev->intx_lock);
 220                         pci_intx(assigned_dev->dev, false);
 221                         spin_unlock_irq(&assigned_dev->intx_lock);
 222                         synchronize_irq(assigned_dev->host_irq);
 223                 } else
 224                         disable_irq(assigned_dev->host_irq);
 225
 226                 free_irq(assigned_dev->host_irq, assigned_dev);
 227
 228                 if (assigned_dev->irq_requested_type & KVM_DEV_IRQ_HOST_MSI)
 229                         pci_disable_msi(assigned_dev->dev);
 230         }
 231
 232         assigned_dev->irq_requested_type &= ~(KVM_DEV_IRQ_HOST_MASK);
 233 }
 234
 235 static int kvm_deassign_irq(struct kvm *kvm,
 236                             struct kvm_assigned_dev_kernel *assigned_dev,
 237                             unsigned long irq_requested_type)
 238 {
 239         unsigned long guest_irq_type, host_irq_type;
 240
 241         if (!irqchip_in_kernel(kvm))
 242                 return -EINVAL;
 243         /* no irq assignment to deassign */
 244         if (!assigned_dev->irq_requested_type)
 245                 return -ENXIO;
 246
 247         host_irq_type = irq_requested_type & KVM_DEV_IRQ_HOST_MASK;
 248         guest_irq_type = irq_requested_type & KVM_DEV_IRQ_GUEST_MASK;
 249
 250         if (host_irq_type)
 251                 deassign_host_irq(kvm, assigned_dev);
 252         if (guest_irq_type)
 253                 deassign_guest_irq(kvm, assigned_dev);
 254
 255         return 0;
 256 }
 257
 258 static void kvm_free_assigned_irq(struct kvm *kvm,
 259                                   struct kvm_assigned_dev_kernel *assigned_dev)
 260 {
 261         kvm_deassign_irq(kvm, assigned_dev, assigned_dev->irq_requested_type);
 262 }
 263
 264 static void kvm_free_assigned_device(struct kvm *kvm,
 265                                      struct kvm_assigned_dev_kernel
 266                                      *assigned_dev)
 267 {
 268         kvm_free_assigned_irq(kvm, assigned_dev);
 269
 270         pci_reset_function(assigned_dev->dev);
 271         if (pci_load_and_free_saved_state(assigned_dev->dev,
 272                                           &assigned_dev->pci_saved_state))
 273                 printk(KERN_INFO "%s: Couldn't reload %s saved state\n",
 274                        __func__, dev_name(&assigned_dev->dev->dev));
 275         else
 276                 pci_restore_state(assigned_dev->dev);
 277
 278         assigned_dev->dev->dev_flags &= ~PCI_DEV_FLAGS_ASSIGNED;
 279
 280         pci_release_regions(assigned_dev->dev);
 281         pci_disable_device(assigned_dev->dev);
 282         pci_dev_put(assigned_dev->dev);
 283
 284         list_del(&assigned_dev->list);
 285         kfree(assigned_dev);
 286 }
 287
 288 void kvm_free_all_assigned_devices(struct kvm *kvm)
 289 {
 290         struct list_head *ptr, *ptr2;
 291         struct kvm_assigned_dev_kernel *assigned_dev;
 292
 293         list_for_each_safe(ptr, ptr2, &kvm->arch.assigned_dev_head) {
 294                 assigned_dev = list_entry(ptr,
 295                                           struct kvm_assigned_dev_kernel,
 296                                           list);
 297
 298                 kvm_free_assigned_device(kvm, assigned_dev);
 299         }
 300 }
 301
 302 static int assigned_device_enable_host_intx(struct kvm *kvm,
 303                                             struct kvm_assigned_dev_kernel *dev)
 304 {
 305         irq_handler_t irq_handler;
 306         unsigned long flags;
 307
 308         dev->host_irq = dev->dev->irq;
 309
 310         /*
 311          * We can only share the IRQ line with other host devices if we are
 312          * able to disable the IRQ source at device-level - independently of
 313          * the guest driver. Otherwise host devices may suffer from unbounded
 314          * IRQ latencies when the guest keeps the line asserted.
 315          */
 316         if (dev->flags & KVM_DEV_ASSIGN_PCI_2_3) {
 317                 irq_handler = kvm_assigned_dev_intx;
 318                 flags = IRQF_SHARED;
 319         } else {
 320                 irq_handler = NULL;
 321                 flags = IRQF_ONESHOT;
 322         }
 323         if (request_threaded_irq(dev->host_irq, irq_handler,
 324                                  kvm_assigned_dev_thread_intx, flags,
 325                                  dev->irq_name, dev))
 326                 return -EIO;
 327
 328         if (dev->flags & KVM_DEV_ASSIGN_PCI_2_3) {
 329                 spin_lock_irq(&dev->intx_lock);
 330                 pci_intx(dev->dev, true);
 331                 spin_unlock_irq(&dev->intx_lock);
 332         }
 333         return 0;
 334 }
 335
 336 #ifdef __KVM_HAVE_MSI
 337 static irqreturn_t kvm_assigned_dev_msi(int irq, void *dev_id)
 338 {
 339         return IRQ_WAKE_THREAD;
 340 }
 341
 342 static int assigned_device_enable_host_msi(struct kvm *kvm,
 343                                            struct kvm_assigned_dev_kernel *dev)
 344 {
 345         int r;
 346
 347         if (!dev->dev->msi_enabled) {
 348                 r = pci_enable_msi(dev->dev);
 349                 if (r)
 350                         return r;
 351         }
 352
 353         dev->host_irq = dev->dev->irq;
 354         if (request_threaded_irq(dev->host_irq, kvm_assigned_dev_msi,
 355                                  kvm_assigned_dev_thread_msi, 0,
 356                                  dev->irq_name, dev)) {
 357                 pci_disable_msi(dev->dev);
 358                 return -EIO;
 359         }
 360
 361         return 0;
 362 }
 363 #endif
 364
 365 #ifdef __KVM_HAVE_MSIX
 366 static irqreturn_t kvm_assigned_dev_msix(int irq, void *dev_id)
 367 {
 368         return IRQ_WAKE_THREAD;
 369 }
 370
 371 static int assigned_device_enable_host_msix(struct kvm *kvm,
 372                                             struct kvm_assigned_dev_kernel *dev)
 373 {
 374         int i, r = -EINVAL;
 375
 376         /* host_msix_entries and guest_msix_entries should have been
 377          * initialized */
 378         if (dev->entries_nr == 0)
 379                 return r;
 380
 381         r = pci_enable_msix(dev->dev, dev->host_msix_entries, dev->entries_nr);
 382         if (r)
 383                 return r;
 384
 385         for (i = 0; i < dev->entries_nr; i++) {
 386                 r = request_threaded_irq(dev->host_msix_entries[i].vector,
 387                                          kvm_assigned_dev_msix,
 388                                          kvm_assigned_dev_thread_msix,
 389                                          0, dev->irq_name, dev);
 390                 if (r)
 391                         goto err;
 392         }
 393
 394         return 0;
 395 err:
 396         for (i -= 1; i >= 0; i--)
 397                 free_irq(dev->host_msix_entries[i].vector, dev);
 398         pci_disable_msix(dev->dev);
 399         return r;
 400 }
 401
 402 #endif
 403
 404 static int assigned_device_enable_guest_intx(struct kvm *kvm,
 405                                 struct kvm_assigned_dev_kernel *dev,
 406                                 struct kvm_assigned_irq *irq)
 407 {
 408         dev->guest_irq = irq->guest_irq;
 409         dev->ack_notifier.gsi = irq->guest_irq;
 410         return 0;
 411 }
 412
 413 #ifdef __KVM_HAVE_MSI
 414 static int assigned_device_enable_guest_msi(struct kvm *kvm,
 415                         struct kvm_assigned_dev_kernel *dev,
 416                         struct kvm_assigned_irq *irq)
 417 {
 418         dev->guest_irq = irq->guest_irq;
 419         dev->ack_notifier.gsi = -1;
 420         return 0;
 421 }
 422 #endif
 423
 424 #ifdef __KVM_HAVE_MSIX
 425 static int assigned_device_enable_guest_msix(struct kvm *kvm,
 426                         struct kvm_assigned_dev_kernel *dev,
 427                         struct kvm_assigned_irq *irq)
 428 {
 429         dev->guest_irq = irq->guest_irq;
 430         dev->ack_notifier.gsi = -1;
 431         return 0;
 432 }
 433 #endif
 434
 435 static int assign_host_irq(struct kvm *kvm,
 436                            struct kvm_assigned_dev_kernel *dev,
 437                            __u32 host_irq_type)
 438 {
 439         int r = -EEXIST;
 440
 441         if (dev->irq_requested_type & KVM_DEV_IRQ_HOST_MASK)
 442                 return r;
 443
 444         snprintf(dev->irq_name, sizeof(dev->irq_name), "kvm:%s",
 445                  pci_name(dev->dev));
 446
 447         switch (host_irq_type) {
 448         case KVM_DEV_IRQ_HOST_INTX:
 449                 r = assigned_device_enable_host_intx(kvm, dev);
 450                 break;
 451 #ifdef __KVM_HAVE_MSI
 452         case KVM_DEV_IRQ_HOST_MSI:
 453                 r = assigned_device_enable_host_msi(kvm, dev);
 454                 break;
 455 #endif
 456 #ifdef __KVM_HAVE_MSIX
 457         case KVM_DEV_IRQ_HOST_MSIX:
 458                 r = assigned_device_enable_host_msix(kvm, dev);
 459                 break;
 460 #endif
 461         default:
 462                 r = -EINVAL;
 463         }
 464         dev->host_irq_disabled = false;
 465
 466         if (!r)
 467                 dev->irq_requested_type |= host_irq_type;
 468
 469         return r;
 470 }
 471
 472 static int assign_guest_irq(struct kvm *kvm,
 473                             struct kvm_assigned_dev_kernel *dev,
 474                             struct kvm_assigned_irq *irq,
 475                             unsigned long guest_irq_type)
 476 {
 477         int id;
 478         int r = -EEXIST;
 479
 480         if (dev->irq_requested_type & KVM_DEV_IRQ_GUEST_MASK)
 481                 return r;
 482
 483         id = kvm_request_irq_source_id(kvm);
 484         if (id < 0)
 485                 return id;
 486
 487         dev->irq_source_id = id;
 488
 489         switch (guest_irq_type) {
 490         case KVM_DEV_IRQ_GUEST_INTX:
 491                 r = assigned_device_enable_guest_intx(kvm, dev, irq);
 492                 break;
 493 #ifdef __KVM_HAVE_MSI
 494         case KVM_DEV_IRQ_GUEST_MSI:
 495                 r = assigned_device_enable_guest_msi(kvm, dev, irq);
 496                 break;
 497 #endif
 498 #ifdef __KVM_HAVE_MSIX
 499         case KVM_DEV_IRQ_GUEST_MSIX:
 500                 r = assigned_device_enable_guest_msix(kvm, dev, irq);
 501                 break;
 502 #endif
 503         default:
 504                 r = -EINVAL;
 505         }
 506
 507         if (!r) {
 508                 dev->irq_requested_type |= guest_irq_type;
 509                 if (dev->ack_notifier.gsi != -1)
 510                         kvm_register_irq_ack_notifier(kvm, &dev->ack_notifier);
 511         } else
 512                 kvm_free_irq_source_id(kvm, dev->irq_source_id);
 513
 514         return r;
 515 }
 516
 517 /* TODO Deal with KVM_DEV_IRQ_ASSIGNED_MASK_MSIX */
 518 static int kvm_vm_ioctl_assign_irq(struct kvm *kvm,
 519                                    struct kvm_assigned_irq *assigned_irq)
 520 {
 521         int r = -EINVAL;
 522         struct kvm_assigned_dev_kernel *match;
 523         unsigned long host_irq_type, guest_irq_type;
 524
 525         if (!irqchip_in_kernel(kvm))
 526                 return r;
 527
 528         mutex_lock(&kvm->lock);
 529         r = -ENODEV;
 530         match = kvm_find_assigned_dev(&kvm->arch.assigned_dev_head,
 531                                       assigned_irq->assigned_dev_id);
 532         if (!match)
 533                 goto out;
 534
 535         host_irq_type = (assigned_irq->flags & KVM_DEV_IRQ_HOST_MASK);
 536         guest_irq_type = (assigned_irq->flags & KVM_DEV_IRQ_GUEST_MASK);
 537
 538         r = -EINVAL;
 539         /* can only assign one type at a time */
 540         if (hweight_long(host_irq_type) > 1)
 541                 goto out;
 542         if (hweight_long(guest_irq_type) > 1)
 543                 goto out;
 544         if (host_irq_type == 0 && guest_irq_type == 0)
 545                 goto out;
 546
 547         r = 0;
 548         if (host_irq_type)
 549                 r = assign_host_irq(kvm, match, host_irq_type);
 550         if (r)
 551                 goto out;
 552
 553         if (guest_irq_type)
 554                 r = assign_guest_irq(kvm, match, assigned_irq, guest_irq_type);
 555 out:
 556         mutex_unlock(&kvm->lock);
 557         return r;
 558 }
 559
 560 static int kvm_vm_ioctl_deassign_dev_irq(struct kvm *kvm,
 561                                          struct kvm_assigned_irq
 562                                          *assigned_irq)
 563 {
 564         int r = -ENODEV;
 565         struct kvm_assigned_dev_kernel *match;
 566         unsigned long irq_type;
 567
 568         mutex_lock(&kvm->lock);
 569
 570         match = kvm_find_assigned_dev(&kvm->arch.assigned_dev_head,
 571                                       assigned_irq->assigned_dev_id);
 572         if (!match)
 573                 goto out;
 574
 575         irq_type = assigned_irq->flags & (KVM_DEV_IRQ_HOST_MASK |
 576                                           KVM_DEV_IRQ_GUEST_MASK);
 577         r = kvm_deassign_irq(kvm, match, irq_type);
 578 out:
 579         mutex_unlock(&kvm->lock);
 580         return r;
 581 }
 582
 583 /*
 584  * We want to test whether the caller has been granted permissions to
 585  * use this device.  To be able to configure and control the device,
 586  * the user needs access to PCI configuration space and BAR resources.
 587  * These are accessed through PCI sysfs.  PCI config space is often
 588  * passed to the process calling this ioctl via file descriptor, so we
 589  * can't rely on access to that file.  We can check for permissions
 590  * on each of the BAR resource files, which is a pretty clear
 591  * indicator that the user has been granted access to the device.
 592  */
 593 static int probe_sysfs_permissions(struct pci_dev *dev)
 594 {
 595 #ifdef CONFIG_SYSFS
 596         int i;
 597         bool bar_found = false;
 598
 599         for (i = PCI_STD_RESOURCES; i <= PCI_STD_RESOURCE_END; i++) {
 600                 char *kpath, *syspath;
 601                 struct path path;
 602                 struct inode *inode;
 603                 int r;
 604
 605                 if (!pci_resource_len(dev, i))
 606                         continue;
 607
 608                 kpath = kobject_get_path(&dev->dev.kobj, GFP_KERNEL);
 609                 if (!kpath)
 610                         return -ENOMEM;
 611
 612                 /* Per sysfs-rules, sysfs is always at /sys */
 613                 syspath = kasprintf(GFP_KERNEL, "/sys%s/resource%d", kpath, i);
 614                 kfree(kpath);
 615                 if (!syspath)
 616                         return -ENOMEM;
 617
 618                 r = kern_path(syspath, LOOKUP_FOLLOW, &path);
 619                 kfree(syspath);
 620                 if (r)
 621                         return r;
 622
 623                 inode = path.dentry->d_inode;
 624
 625                 r = inode_permission(inode, MAY_READ | MAY_WRITE | MAY_ACCESS);
 626                 path_put(&path);
 627                 if (r)
 628                         return r;
 629
 630                 bar_found = true;
 631         }
 632
 633         /* If no resources, probably something special */
 634         if (!bar_found)
 635                 return -EPERM;
 636
 637         return 0;
 638 #else
 639         return -EINVAL; /* No way to control the device without sysfs */
 640 #endif
 641 }
 642
 643 static int kvm_vm_ioctl_assign_device(struct kvm *kvm,
 644                                       struct kvm_assigned_pci_dev *assigned_dev)
 645 {
 646         int r = 0, idx;
 647         struct kvm_assigned_dev_kernel *match;
 648         struct pci_dev *dev;
 649
 650         if (!(assigned_dev->flags & KVM_DEV_ASSIGN_ENABLE_IOMMU))
 651                 return -EINVAL;
 652
 653         mutex_lock(&kvm->lock);
 654         idx = srcu_read_lock(&kvm->srcu);
 655
 656         match = kvm_find_assigned_dev(&kvm->arch.assigned_dev_head,
 657                                       assigned_dev->assigned_dev_id);
 658         if (match) {
 659                 /* device already assigned */
 660                 r = -EEXIST;
 661                 goto out;
 662         }
 663
 664         match = kzalloc(sizeof(struct kvm_assigned_dev_kernel), GFP_KERNEL);
 665         if (match == NULL) {
 666                 printk(KERN_INFO "%s: Couldn't allocate memory\n",
 667                        __func__);
 668                 r = -ENOMEM;
 669                 goto out;
 670         }
 671         dev = pci_get_domain_bus_and_slot(assigned_dev->segnr,
 672                                    assigned_dev->busnr,
 673                                    assigned_dev->devfn);
 674         if (!dev) {
 675                 printk(KERN_INFO "%s: host device not found\n", __func__);
 676                 r = -EINVAL;
 677                 goto out_free;
 678         }
 679
 680         /* Don't allow bridges to be assigned */
 681         if (dev->hdr_type != PCI_HEADER_TYPE_NORMAL) {
 682                 r = -EPERM;
 683                 goto out_put;
 684         }
 685
 686         r = probe_sysfs_permissions(dev);
 687         if (r)
 688                 goto out_put;
 689
 690         if (pci_enable_device(dev)) {
 691                 printk(KERN_INFO "%s: Could not enable PCI device\n", __func__);
 692                 r = -EBUSY;
 693                 goto out_put;
 694         }
 695         r = pci_request_regions(dev, "kvm_assigned_device");
 696         if (r) {
 697                 printk(KERN_INFO "%s: Could not get access to device regions\n",
 698                        __func__);
 699                 goto out_disable;
 700         }
 701
 702         pci_reset_function(dev);
 703         pci_save_state(dev);
 704         match->pci_saved_state = pci_store_saved_state(dev);
 705         if (!match->pci_saved_state)
 706                 printk(KERN_DEBUG "%s: Couldn't store %s saved state\n",
 707                        __func__, dev_name(&dev->dev));
 708
 709         if (!pci_intx_mask_supported(dev))
 710                 assigned_dev->flags &= ~KVM_DEV_ASSIGN_PCI_2_3;
 711
 712         match->assigned_dev_id = assigned_dev->assigned_dev_id;
 713         match->host_segnr = assigned_dev->segnr;
 714         match->host_busnr = assigned_dev->busnr;
 715         match->host_devfn = assigned_dev->devfn;
 716         match->flags = assigned_dev->flags;
 717         match->dev = dev;
 718         spin_lock_init(&match->intx_lock);
 719         spin_lock_init(&match->intx_mask_lock);
 720         match->irq_source_id = -1;
 721         match->kvm = kvm;
 722         match->ack_notifier.irq_acked = kvm_assigned_dev_ack_irq;
 723
 724         list_add(&match->list, &kvm->arch.assigned_dev_head);
 725
 726         if (!kvm->arch.iommu_domain) {
 727                 r = kvm_iommu_map_guest(kvm);
 728                 if (r)
 729                         goto out_list_del;
 730         }
 731         r = kvm_assign_device(kvm, match);
 732         if (r)
 733                 goto out_list_del;
 734
 735 out:
 736         srcu_read_unlock(&kvm->srcu, idx);
 737         mutex_unlock(&kvm->lock);
 738         return r;
 739 out_list_del:
 740         if (pci_load_and_free_saved_state(dev, &match->pci_saved_state))
 741                 printk(KERN_INFO "%s: Couldn't reload %s saved state\n",
 742                        __func__, dev_name(&dev->dev));
 743         list_del(&match->list);
 744         pci_release_regions(dev);
 745 out_disable:
 746         pci_disable_device(dev);
 747 out_put:
 748         pci_dev_put(dev);
 749 out_free:
 750         kfree(match);
 751         srcu_read_unlock(&kvm->srcu, idx);
 752         mutex_unlock(&kvm->lock);
 753         return r;
 754 }
 755
 756 static int kvm_vm_ioctl_deassign_device(struct kvm *kvm,
 757                 struct kvm_assigned_pci_dev *assigned_dev)
 758 {
 759         int r = 0;
 760         struct kvm_assigned_dev_kernel *match;
 761
 762         mutex_lock(&kvm->lock);
 763
 764         match = kvm_find_assigned_dev(&kvm->arch.assigned_dev_head,
 765                                       assigned_dev->assigned_dev_id);
 766         if (!match) {
 767                 printk(KERN_INFO "%s: device hasn't been assigned before, "
 768                   "so cannot be deassigned\n", __func__);
 769                 r = -EINVAL;
 770                 goto out;
 771         }
 772
 773         kvm_deassign_device(kvm, match);
 774
 775         kvm_free_assigned_device(kvm, match);
 776
 777 out:
 778         mutex_unlock(&kvm->lock);
 779         return r;
 780 }
 781
 782
 783 #ifdef __KVM_HAVE_MSIX
 784 static int kvm_vm_ioctl_set_msix_nr(struct kvm *kvm,
 785                                     struct kvm_assigned_msix_nr *entry_nr)
 786 {
 787         int r = 0;
 788         struct kvm_assigned_dev_kernel *adev;
 789
 790         mutex_lock(&kvm->lock);
 791
 792         adev = kvm_find_assigned_dev(&kvm->arch.assigned_dev_head,
 793                                       entry_nr->assigned_dev_id);
 794         if (!adev) {
 795                 r = -EINVAL;
 796                 goto msix_nr_out;
 797         }
 798
 799         if (adev->entries_nr == 0) {
 800                 adev->entries_nr = entry_nr->entry_nr;
 801                 if (adev->entries_nr == 0 ||
 802                     adev->entries_nr > KVM_MAX_MSIX_PER_DEV) {
 803                         r = -EINVAL;
 804                         goto msix_nr_out;
 805                 }
 806
 807                 adev->host_msix_entries = kzalloc(sizeof(struct msix_entry) *
 808                                                 entry_nr->entry_nr,
 809                                                 GFP_KERNEL);
 810                 if (!adev->host_msix_entries) {
 811                         r = -ENOMEM;
 812                         goto msix_nr_out;
 813                 }
 814                 adev->guest_msix_entries =
 815                         kzalloc(sizeof(struct msix_entry) * entry_nr->entry_nr,
 816                                 GFP_KERNEL);
 817                 if (!adev->guest_msix_entries) {
 818                         kfree(adev->host_msix_entries);
 819                         r = -ENOMEM;
 820                         goto msix_nr_out;
 821                 }
 822         } else /* Not allowed set MSI-X number twice */
 823                 r = -EINVAL;
 824 msix_nr_out:
 825         mutex_unlock(&kvm->lock);
 826         return r;
 827 }
 828
 829 static int kvm_vm_ioctl_set_msix_entry(struct kvm *kvm,
 830                                        struct kvm_assigned_msix_entry *entry)
 831 {
 832         int r = 0, i;
 833         struct kvm_assigned_dev_kernel *adev;
 834
 835         mutex_lock(&kvm->lock);
 836
 837         adev = kvm_find_assigned_dev(&kvm->arch.assigned_dev_head,
 838                                       entry->assigned_dev_id);
 839
 840         if (!adev) {
 841                 r = -EINVAL;
 842                 goto msix_entry_out;
 843         }
 844
 845         for (i = 0; i < adev->entries_nr; i++)
 846                 if (adev->guest_msix_entries[i].vector == 0 ||
 847                     adev->guest_msix_entries[i].entry == entry->entry) {
 848                         adev->guest_msix_entries[i].entry = entry->entry;
 849                         adev->guest_msix_entries[i].vector = entry->gsi;
 850                         adev->host_msix_entries[i].entry = entry->entry;
 851                         break;
 852                 }
 853         if (i == adev->entries_nr) {
 854                 r = -ENOSPC;
 855                 goto msix_entry_out;
 856         }
 857
 858 msix_entry_out:
 859         mutex_unlock(&kvm->lock);
 860
 861         return r;
 862 }
 863 #endif
 864
 865 static int kvm_vm_ioctl_set_pci_irq_mask(struct kvm *kvm,
 866                 struct kvm_assigned_pci_dev *assigned_dev)
 867 {
 868         int r = 0;
 869         struct kvm_assigned_dev_kernel *match;
 870
 871         mutex_lock(&kvm->lock);
 872
 873         match = kvm_find_assigned_dev(&kvm->arch.assigned_dev_head,
 874                                       assigned_dev->assigned_dev_id);
 875         if (!match) {
 876                 r = -ENODEV;
 877                 goto out;
 878         }
 879
 880         spin_lock(&match->intx_mask_lock);
 881
 882         match->flags &= ~KVM_DEV_ASSIGN_MASK_INTX;
 883         match->flags |= assigned_dev->flags & KVM_DEV_ASSIGN_MASK_INTX;
 884
 885         if (match->irq_requested_type & KVM_DEV_IRQ_GUEST_INTX) {
 886                 if (assigned_dev->flags & KVM_DEV_ASSIGN_MASK_INTX) {
 887                         kvm_set_irq(match->kvm, match->irq_source_id,
 888                                     match->guest_irq, 0);
 889                         /*
 890                          * Masking at hardware-level is performed on demand,
 891                          * i.e. when an IRQ actually arrives at the host.
 892                          */
 893                 } else if (!(assigned_dev->flags & KVM_DEV_ASSIGN_PCI_2_3)) {
 894                         /*
 895                          * Unmask the IRQ line if required. Unmasking at
 896                          * device level will be performed by user space.
 897                          */
 898                         spin_lock_irq(&match->intx_lock);
 899                         if (match->host_irq_disabled) {
 900                                 enable_irq(match->host_irq);
 901                                 match->host_irq_disabled = false;
 902                         }
 903                         spin_unlock_irq(&match->intx_lock);
 904                 }
 905         }
 906
 907         spin_unlock(&match->intx_mask_lock);
 908
 909 out:
 910         mutex_unlock(&kvm->lock);
 911         return r;
 912 }
 913
 914 long kvm_vm_ioctl_assigned_device(struct kvm *kvm, unsigned ioctl,
 915                                   unsigned long arg)
 916 {
 917         void __user *argp = (void __user *)arg;
 918         int r;
 919
 920         switch (ioctl) {
 921         case KVM_ASSIGN_PCI_DEVICE: {
 922                 struct kvm_assigned_pci_dev assigned_dev;
 923
 924                 r = -EFAULT;
 925                 if (copy_from_user(&assigned_dev, argp, sizeof assigned_dev))
 926                         goto out;
 927                 r = kvm_vm_ioctl_assign_device(kvm, &assigned_dev);
 928                 if (r)
 929                         goto out;
 930                 break;
 931         }
 932         case KVM_ASSIGN_IRQ: {
 933                 r = -EOPNOTSUPP;
 934                 break;
 935         }
 936         case KVM_ASSIGN_DEV_IRQ: {
 937                 struct kvm_assigned_irq assigned_irq;
 938
 939                 r = -EFAULT;
 940                 if (copy_from_user(&assigned_irq, argp, sizeof assigned_irq))
 941                         goto out;
 942                 r = kvm_vm_ioctl_assign_irq(kvm, &assigned_irq);
 943                 if (r)
 944                         goto out;
 945                 break;
 946         }
 947         case KVM_DEASSIGN_DEV_IRQ: {
 948                 struct kvm_assigned_irq assigned_irq;
 949
 950                 r = -EFAULT;
 951                 if (copy_from_user(&assigned_irq, argp, sizeof assigned_irq))
 952                         goto out;
 953                 r = kvm_vm_ioctl_deassign_dev_irq(kvm, &assigned_irq);
 954                 if (r)
 955                         goto out;
 956                 break;
 957         }
 958         case KVM_DEASSIGN_PCI_DEVICE: {
 959                 struct kvm_assigned_pci_dev assigned_dev;
 960
 961                 r = -EFAULT;
 962                 if (copy_from_user(&assigned_dev, argp, sizeof assigned_dev))
 963                         goto out;
 964                 r = kvm_vm_ioctl_deassign_device(kvm, &assigned_dev);
 965                 if (r)
 966                         goto out;
 967                 break;
 968         }
 969 #ifdef KVM_CAP_IRQ_ROUTING
 970         case KVM_SET_GSI_ROUTING: {
 971                 struct kvm_irq_routing routing;
 972                 struct kvm_irq_routing __user *urouting;
 973                 struct kvm_irq_routing_entry *entries;
 974
 975                 r = -EFAULT;
 976                 if (copy_from_user(&routing, argp, sizeof(routing)))
 977                         goto out;
 978                 r = -EINVAL;
 979                 if (routing.nr >= KVM_MAX_IRQ_ROUTES)
 980                         goto out;
 981                 if (routing.flags)
 982                         goto out;
 983                 r = -ENOMEM;
 984                 entries = vmalloc(routing.nr * sizeof(*entries));
 985                 if (!entries)
 986                         goto out;
 987                 r = -EFAULT;
 988                 urouting = argp;
 989                 if (copy_from_user(entries, urouting->entries,
 990                                    routing.nr * sizeof(*entries)))
 991                         goto out_free_irq_routing;
 992                 r = kvm_set_irq_routing(kvm, entries, routing.nr,
 993                                         routing.flags);
 994         out_free_irq_routing:
 995                 vfree(entries);
 996                 break;
 997         }
 998 #endif /* KVM_CAP_IRQ_ROUTING */
 999 #ifdef __KVM_HAVE_MSIX
1000         case KVM_ASSIGN_SET_MSIX_NR: {
1001                 struct kvm_assigned_msix_nr entry_nr;
1002                 r = -EFAULT;
1003                 if (copy_from_user(&entry_nr, argp, sizeof entry_nr))
1004                         goto out;
1005                 r = kvm_vm_ioctl_set_msix_nr(kvm, &entry_nr);
1006                 if (r)
1007                         goto out;
1008                 break;
1009         }
1010         case KVM_ASSIGN_SET_MSIX_ENTRY: {
1011                 struct kvm_assigned_msix_entry entry;
1012                 r = -EFAULT;
1013                 if (copy_from_user(&entry, argp, sizeof entry))
1014                         goto out;
1015                 r = kvm_vm_ioctl_set_msix_entry(kvm, &entry);
1016                 if (r)
1017                         goto out;
1018                 break;
1019         }
1020 #endif
1021         case KVM_ASSIGN_SET_INTX_MASK: {
1022                 struct kvm_assigned_pci_dev assigned_dev;
1023
1024                 r = -EFAULT;
1025                 if (copy_from_user(&assigned_dev, argp, sizeof assigned_dev))
1026                         goto out;
1027                 r = kvm_vm_ioctl_set_pci_irq_mask(kvm, &assigned_dev);
1028                 break;
1029         }
1030         default:
1031                 r = -ENOTTY;
1032                 break;
1033         }
1034 out:
1035         return r;
1036 }