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 int assigned_device_enable_host_msi(struct kvm *kvm,
 338                                            struct kvm_assigned_dev_kernel *dev)
 339 {
 340         int r;
 341
 342         if (!dev->dev->msi_enabled) {
 343                 r = pci_enable_msi(dev->dev);
 344                 if (r)
 345                         return r;
 346         }
 347
 348         dev->host_irq = dev->dev->irq;
 349         if (request_threaded_irq(dev->host_irq, NULL,
 350                                  kvm_assigned_dev_thread_msi, 0,
 351                                  dev->irq_name, dev)) {
 352                 pci_disable_msi(dev->dev);
 353                 return -EIO;
 354         }
 355
 356         return 0;
 357 }
 358 #endif
 359
 360 #ifdef __KVM_HAVE_MSIX
 361 static int assigned_device_enable_host_msix(struct kvm *kvm,
 362                                             struct kvm_assigned_dev_kernel *dev)
 363 {
 364         int i, r = -EINVAL;
 365
 366         /* host_msix_entries and guest_msix_entries should have been
 367          * initialized */
 368         if (dev->entries_nr == 0)
 369                 return r;
 370
 371         r = pci_enable_msix(dev->dev, dev->host_msix_entries, dev->entries_nr);
 372         if (r)
 373                 return r;
 374
 375         for (i = 0; i < dev->entries_nr; i++) {
 376                 r = request_threaded_irq(dev->host_msix_entries[i].vector,
 377                                          NULL, kvm_assigned_dev_thread_msix,
 378                                          0, dev->irq_name, dev);
 379                 if (r)
 380                         goto err;
 381         }
 382
 383         return 0;
 384 err:
 385         for (i -= 1; i >= 0; i--)
 386                 free_irq(dev->host_msix_entries[i].vector, dev);
 387         pci_disable_msix(dev->dev);
 388         return r;
 389 }
 390
 391 #endif
 392
 393 static int assigned_device_enable_guest_intx(struct kvm *kvm,
 394                                 struct kvm_assigned_dev_kernel *dev,
 395                                 struct kvm_assigned_irq *irq)
 396 {
 397         dev->guest_irq = irq->guest_irq;
 398         dev->ack_notifier.gsi = irq->guest_irq;
 399         return 0;
 400 }
 401
 402 #ifdef __KVM_HAVE_MSI
 403 static int assigned_device_enable_guest_msi(struct kvm *kvm,
 404                         struct kvm_assigned_dev_kernel *dev,
 405                         struct kvm_assigned_irq *irq)
 406 {
 407         dev->guest_irq = irq->guest_irq;
 408         dev->ack_notifier.gsi = -1;
 409         return 0;
 410 }
 411 #endif
 412
 413 #ifdef __KVM_HAVE_MSIX
 414 static int assigned_device_enable_guest_msix(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 static int assign_host_irq(struct kvm *kvm,
 425                            struct kvm_assigned_dev_kernel *dev,
 426                            __u32 host_irq_type)
 427 {
 428         int r = -EEXIST;
 429
 430         if (dev->irq_requested_type & KVM_DEV_IRQ_HOST_MASK)
 431                 return r;
 432
 433         snprintf(dev->irq_name, sizeof(dev->irq_name), "kvm:%s",
 434                  pci_name(dev->dev));
 435
 436         switch (host_irq_type) {
 437         case KVM_DEV_IRQ_HOST_INTX:
 438                 r = assigned_device_enable_host_intx(kvm, dev);
 439                 break;
 440 #ifdef __KVM_HAVE_MSI
 441         case KVM_DEV_IRQ_HOST_MSI:
 442                 r = assigned_device_enable_host_msi(kvm, dev);
 443                 break;
 444 #endif
 445 #ifdef __KVM_HAVE_MSIX
 446         case KVM_DEV_IRQ_HOST_MSIX:
 447                 r = assigned_device_enable_host_msix(kvm, dev);
 448                 break;
 449 #endif
 450         default:
 451                 r = -EINVAL;
 452         }
 453         dev->host_irq_disabled = false;
 454
 455         if (!r)
 456                 dev->irq_requested_type |= host_irq_type;
 457
 458         return r;
 459 }
 460
 461 static int assign_guest_irq(struct kvm *kvm,
 462                             struct kvm_assigned_dev_kernel *dev,
 463                             struct kvm_assigned_irq *irq,
 464                             unsigned long guest_irq_type)
 465 {
 466         int id;
 467         int r = -EEXIST;
 468
 469         if (dev->irq_requested_type & KVM_DEV_IRQ_GUEST_MASK)
 470                 return r;
 471
 472         id = kvm_request_irq_source_id(kvm);
 473         if (id < 0)
 474                 return id;
 475
 476         dev->irq_source_id = id;
 477
 478         switch (guest_irq_type) {
 479         case KVM_DEV_IRQ_GUEST_INTX:
 480                 r = assigned_device_enable_guest_intx(kvm, dev, irq);
 481                 break;
 482 #ifdef __KVM_HAVE_MSI
 483         case KVM_DEV_IRQ_GUEST_MSI:
 484                 r = assigned_device_enable_guest_msi(kvm, dev, irq);
 485                 break;
 486 #endif
 487 #ifdef __KVM_HAVE_MSIX
 488         case KVM_DEV_IRQ_GUEST_MSIX:
 489                 r = assigned_device_enable_guest_msix(kvm, dev, irq);
 490                 break;
 491 #endif
 492         default:
 493                 r = -EINVAL;
 494         }
 495
 496         if (!r) {
 497                 dev->irq_requested_type |= guest_irq_type;
 498                 if (dev->ack_notifier.gsi != -1)
 499                         kvm_register_irq_ack_notifier(kvm, &dev->ack_notifier);
 500         } else
 501                 kvm_free_irq_source_id(kvm, dev->irq_source_id);
 502
 503         return r;
 504 }
 505
 506 /* TODO Deal with KVM_DEV_IRQ_ASSIGNED_MASK_MSIX */
 507 static int kvm_vm_ioctl_assign_irq(struct kvm *kvm,
 508                                    struct kvm_assigned_irq *assigned_irq)
 509 {
 510         int r = -EINVAL;
 511         struct kvm_assigned_dev_kernel *match;
 512         unsigned long host_irq_type, guest_irq_type;
 513
 514         if (!irqchip_in_kernel(kvm))
 515                 return r;
 516
 517         mutex_lock(&kvm->lock);
 518         r = -ENODEV;
 519         match = kvm_find_assigned_dev(&kvm->arch.assigned_dev_head,
 520                                       assigned_irq->assigned_dev_id);
 521         if (!match)
 522                 goto out;
 523
 524         host_irq_type = (assigned_irq->flags & KVM_DEV_IRQ_HOST_MASK);
 525         guest_irq_type = (assigned_irq->flags & KVM_DEV_IRQ_GUEST_MASK);
 526
 527         r = -EINVAL;
 528         /* can only assign one type at a time */
 529         if (hweight_long(host_irq_type) > 1)
 530                 goto out;
 531         if (hweight_long(guest_irq_type) > 1)
 532                 goto out;
 533         if (host_irq_type == 0 && guest_irq_type == 0)
 534                 goto out;
 535
 536         r = 0;
 537         if (host_irq_type)
 538                 r = assign_host_irq(kvm, match, host_irq_type);
 539         if (r)
 540                 goto out;
 541
 542         if (guest_irq_type)
 543                 r = assign_guest_irq(kvm, match, assigned_irq, guest_irq_type);
 544 out:
 545         mutex_unlock(&kvm->lock);
 546         return r;
 547 }
 548
 549 static int kvm_vm_ioctl_deassign_dev_irq(struct kvm *kvm,
 550                                          struct kvm_assigned_irq
 551                                          *assigned_irq)
 552 {
 553         int r = -ENODEV;
 554         struct kvm_assigned_dev_kernel *match;
 555         unsigned long irq_type;
 556
 557         mutex_lock(&kvm->lock);
 558
 559         match = kvm_find_assigned_dev(&kvm->arch.assigned_dev_head,
 560                                       assigned_irq->assigned_dev_id);
 561         if (!match)
 562                 goto out;
 563
 564         irq_type = assigned_irq->flags & (KVM_DEV_IRQ_HOST_MASK |
 565                                           KVM_DEV_IRQ_GUEST_MASK);
 566         r = kvm_deassign_irq(kvm, match, irq_type);
 567 out:
 568         mutex_unlock(&kvm->lock);
 569         return r;
 570 }
 571
 572 /*
 573  * We want to test whether the caller has been granted permissions to
 574  * use this device.  To be able to configure and control the device,
 575  * the user needs access to PCI configuration space and BAR resources.
 576  * These are accessed through PCI sysfs.  PCI config space is often
 577  * passed to the process calling this ioctl via file descriptor, so we
 578  * can't rely on access to that file.  We can check for permissions
 579  * on each of the BAR resource files, which is a pretty clear
 580  * indicator that the user has been granted access to the device.
 581  */
 582 static int probe_sysfs_permissions(struct pci_dev *dev)
 583 {
 584 #ifdef CONFIG_SYSFS
 585         int i;
 586         bool bar_found = false;
 587
 588         for (i = PCI_STD_RESOURCES; i <= PCI_STD_RESOURCE_END; i++) {
 589                 char *kpath, *syspath;
 590                 struct path path;
 591                 struct inode *inode;
 592                 int r;
 593
 594                 if (!pci_resource_len(dev, i))
 595                         continue;
 596
 597                 kpath = kobject_get_path(&dev->dev.kobj, GFP_KERNEL);
 598                 if (!kpath)
 599                         return -ENOMEM;
 600
 601                 /* Per sysfs-rules, sysfs is always at /sys */
 602                 syspath = kasprintf(GFP_KERNEL, "/sys%s/resource%d", kpath, i);
 603                 kfree(kpath);
 604                 if (!syspath)
 605                         return -ENOMEM;
 606
 607                 r = kern_path(syspath, LOOKUP_FOLLOW, &path);
 608                 kfree(syspath);
 609                 if (r)
 610                         return r;
 611
 612                 inode = path.dentry->d_inode;
 613
 614                 r = inode_permission(inode, MAY_READ | MAY_WRITE | MAY_ACCESS);
 615                 path_put(&path);
 616                 if (r)
 617                         return r;
 618
 619                 bar_found = true;
 620         }
 621
 622         /* If no resources, probably something special */
 623         if (!bar_found)
 624                 return -EPERM;
 625
 626         return 0;
 627 #else
 628         return -EINVAL; /* No way to control the device without sysfs */
 629 #endif
 630 }
 631
 632 static int kvm_vm_ioctl_assign_device(struct kvm *kvm,
 633                                       struct kvm_assigned_pci_dev *assigned_dev)
 634 {
 635         int r = 0, idx;
 636         struct kvm_assigned_dev_kernel *match;
 637         struct pci_dev *dev;
 638         u8 header_type;
 639
 640         if (!(assigned_dev->flags & KVM_DEV_ASSIGN_ENABLE_IOMMU))
 641                 return -EINVAL;
 642
 643         mutex_lock(&kvm->lock);
 644         idx = srcu_read_lock(&kvm->srcu);
 645
 646         match = kvm_find_assigned_dev(&kvm->arch.assigned_dev_head,
 647                                       assigned_dev->assigned_dev_id);
 648         if (match) {
 649                 /* device already assigned */
 650                 r = -EEXIST;
 651                 goto out;
 652         }
 653
 654         match = kzalloc(sizeof(struct kvm_assigned_dev_kernel), GFP_KERNEL);
 655         if (match == NULL) {
 656                 printk(KERN_INFO "%s: Couldn't allocate memory\n",
 657                        __func__);
 658                 r = -ENOMEM;
 659                 goto out;
 660         }
 661         dev = pci_get_domain_bus_and_slot(assigned_dev->segnr,
 662                                    assigned_dev->busnr,
 663                                    assigned_dev->devfn);
 664         if (!dev) {
 665                 printk(KERN_INFO "%s: host device not found\n", __func__);
 666                 r = -EINVAL;
 667                 goto out_free;
 668         }
 669
 670         /* Don't allow bridges to be assigned */
 671         pci_read_config_byte(dev, PCI_HEADER_TYPE, &header_type);
 672         if ((header_type & PCI_HEADER_TYPE) != PCI_HEADER_TYPE_NORMAL) {
 673                 r = -EPERM;
 674                 goto out_put;
 675         }
 676
 677         r = probe_sysfs_permissions(dev);
 678         if (r)
 679                 goto out_put;
 680
 681         if (pci_enable_device(dev)) {
 682                 printk(KERN_INFO "%s: Could not enable PCI device\n", __func__);
 683                 r = -EBUSY;
 684                 goto out_put;
 685         }
 686         r = pci_request_regions(dev, "kvm_assigned_device");
 687         if (r) {
 688                 printk(KERN_INFO "%s: Could not get access to device regions\n",
 689                        __func__);
 690                 goto out_disable;
 691         }
 692
 693         pci_reset_function(dev);
 694         pci_save_state(dev);
 695         match->pci_saved_state = pci_store_saved_state(dev);
 696         if (!match->pci_saved_state)
 697                 printk(KERN_DEBUG "%s: Couldn't store %s saved state\n",
 698                        __func__, dev_name(&dev->dev));
 699
 700         if (!pci_intx_mask_supported(dev))
 701                 assigned_dev->flags &= ~KVM_DEV_ASSIGN_PCI_2_3;
 702
 703         match->assigned_dev_id = assigned_dev->assigned_dev_id;
 704         match->host_segnr = assigned_dev->segnr;
 705         match->host_busnr = assigned_dev->busnr;
 706         match->host_devfn = assigned_dev->devfn;
 707         match->flags = assigned_dev->flags;
 708         match->dev = dev;
 709         spin_lock_init(&match->intx_lock);
 710         spin_lock_init(&match->intx_mask_lock);
 711         match->irq_source_id = -1;
 712         match->kvm = kvm;
 713         match->ack_notifier.irq_acked = kvm_assigned_dev_ack_irq;
 714
 715         list_add(&match->list, &kvm->arch.assigned_dev_head);
 716
 717         if (!kvm->arch.iommu_domain) {
 718                 r = kvm_iommu_map_guest(kvm);
 719                 if (r)
 720                         goto out_list_del;
 721         }
 722         r = kvm_assign_device(kvm, match);
 723         if (r)
 724                 goto out_list_del;
 725
 726 out:
 727         srcu_read_unlock(&kvm->srcu, idx);
 728         mutex_unlock(&kvm->lock);
 729         return r;
 730 out_list_del:
 731         if (pci_load_and_free_saved_state(dev, &match->pci_saved_state))
 732                 printk(KERN_INFO "%s: Couldn't reload %s saved state\n",
 733                        __func__, dev_name(&dev->dev));
 734         list_del(&match->list);
 735         pci_release_regions(dev);
 736 out_disable:
 737         pci_disable_device(dev);
 738 out_put:
 739         pci_dev_put(dev);
 740 out_free:
 741         kfree(match);
 742         srcu_read_unlock(&kvm->srcu, idx);
 743         mutex_unlock(&kvm->lock);
 744         return r;
 745 }
 746
 747 static int kvm_vm_ioctl_deassign_device(struct kvm *kvm,
 748                 struct kvm_assigned_pci_dev *assigned_dev)
 749 {
 750         int r = 0;
 751         struct kvm_assigned_dev_kernel *match;
 752
 753         mutex_lock(&kvm->lock);
 754
 755         match = kvm_find_assigned_dev(&kvm->arch.assigned_dev_head,
 756                                       assigned_dev->assigned_dev_id);
 757         if (!match) {
 758                 printk(KERN_INFO "%s: device hasn't been assigned before, "
 759                   "so cannot be deassigned\n", __func__);
 760                 r = -EINVAL;
 761                 goto out;
 762         }
 763
 764         kvm_deassign_device(kvm, match);
 765
 766         kvm_free_assigned_device(kvm, match);
 767
 768 out:
 769         mutex_unlock(&kvm->lock);
 770         return r;
 771 }
 772
 773
 774 #ifdef __KVM_HAVE_MSIX
 775 static int kvm_vm_ioctl_set_msix_nr(struct kvm *kvm,
 776                                     struct kvm_assigned_msix_nr *entry_nr)
 777 {
 778         int r = 0;
 779         struct kvm_assigned_dev_kernel *adev;
 780
 781         mutex_lock(&kvm->lock);
 782
 783         adev = kvm_find_assigned_dev(&kvm->arch.assigned_dev_head,
 784                                       entry_nr->assigned_dev_id);
 785         if (!adev) {
 786                 r = -EINVAL;
 787                 goto msix_nr_out;
 788         }
 789
 790         if (adev->entries_nr == 0) {
 791                 adev->entries_nr = entry_nr->entry_nr;
 792                 if (adev->entries_nr == 0 ||
 793                     adev->entries_nr > KVM_MAX_MSIX_PER_DEV) {
 794                         r = -EINVAL;
 795                         goto msix_nr_out;
 796                 }
 797
 798                 adev->host_msix_entries = kzalloc(sizeof(struct msix_entry) *
 799                                                 entry_nr->entry_nr,
 800                                                 GFP_KERNEL);
 801                 if (!adev->host_msix_entries) {
 802                         r = -ENOMEM;
 803                         goto msix_nr_out;
 804                 }
 805                 adev->guest_msix_entries =
 806                         kzalloc(sizeof(struct msix_entry) * entry_nr->entry_nr,
 807                                 GFP_KERNEL);
 808                 if (!adev->guest_msix_entries) {
 809                         kfree(adev->host_msix_entries);
 810                         r = -ENOMEM;
 811                         goto msix_nr_out;
 812                 }
 813         } else /* Not allowed set MSI-X number twice */
 814                 r = -EINVAL;
 815 msix_nr_out:
 816         mutex_unlock(&kvm->lock);
 817         return r;
 818 }
 819
 820 static int kvm_vm_ioctl_set_msix_entry(struct kvm *kvm,
 821                                        struct kvm_assigned_msix_entry *entry)
 822 {
 823         int r = 0, i;
 824         struct kvm_assigned_dev_kernel *adev;
 825
 826         mutex_lock(&kvm->lock);
 827
 828         adev = kvm_find_assigned_dev(&kvm->arch.assigned_dev_head,
 829                                       entry->assigned_dev_id);
 830
 831         if (!adev) {
 832                 r = -EINVAL;
 833                 goto msix_entry_out;
 834         }
 835
 836         for (i = 0; i < adev->entries_nr; i++)
 837                 if (adev->guest_msix_entries[i].vector == 0 ||
 838                     adev->guest_msix_entries[i].entry == entry->entry) {
 839                         adev->guest_msix_entries[i].entry = entry->entry;
 840                         adev->guest_msix_entries[i].vector = entry->gsi;
 841                         adev->host_msix_entries[i].entry = entry->entry;
 842                         break;
 843                 }
 844         if (i == adev->entries_nr) {
 845                 r = -ENOSPC;
 846                 goto msix_entry_out;
 847         }
 848
 849 msix_entry_out:
 850         mutex_unlock(&kvm->lock);
 851
 852         return r;
 853 }
 854 #endif
 855
 856 static int kvm_vm_ioctl_set_pci_irq_mask(struct kvm *kvm,
 857                 struct kvm_assigned_pci_dev *assigned_dev)
 858 {
 859         int r = 0;
 860         struct kvm_assigned_dev_kernel *match;
 861
 862         mutex_lock(&kvm->lock);
 863
 864         match = kvm_find_assigned_dev(&kvm->arch.assigned_dev_head,
 865                                       assigned_dev->assigned_dev_id);
 866         if (!match) {
 867                 r = -ENODEV;
 868                 goto out;
 869         }
 870
 871         spin_lock(&match->intx_mask_lock);
 872
 873         match->flags &= ~KVM_DEV_ASSIGN_MASK_INTX;
 874         match->flags |= assigned_dev->flags & KVM_DEV_ASSIGN_MASK_INTX;
 875
 876         if (match->irq_requested_type & KVM_DEV_IRQ_GUEST_INTX) {
 877                 if (assigned_dev->flags & KVM_DEV_ASSIGN_MASK_INTX) {
 878                         kvm_set_irq(match->kvm, match->irq_source_id,
 879                                     match->guest_irq, 0);
 880                         /*
 881                          * Masking at hardware-level is performed on demand,
 882                          * i.e. when an IRQ actually arrives at the host.
 883                          */
 884                 } else if (!(assigned_dev->flags & KVM_DEV_ASSIGN_PCI_2_3)) {
 885                         /*
 886                          * Unmask the IRQ line if required. Unmasking at
 887                          * device level will be performed by user space.
 888                          */
 889                         spin_lock_irq(&match->intx_lock);
 890                         if (match->host_irq_disabled) {
 891                                 enable_irq(match->host_irq);
 892                                 match->host_irq_disabled = false;
 893                         }
 894                         spin_unlock_irq(&match->intx_lock);
 895                 }
 896         }
 897
 898         spin_unlock(&match->intx_mask_lock);
 899
 900 out:
 901         mutex_unlock(&kvm->lock);
 902         return r;
 903 }
 904
 905 long kvm_vm_ioctl_assigned_device(struct kvm *kvm, unsigned ioctl,
 906                                   unsigned long arg)
 907 {
 908         void __user *argp = (void __user *)arg;
 909         int r;
 910
 911         switch (ioctl) {
 912         case KVM_ASSIGN_PCI_DEVICE: {
 913                 struct kvm_assigned_pci_dev assigned_dev;
 914
 915                 r = -EFAULT;
 916                 if (copy_from_user(&assigned_dev, argp, sizeof assigned_dev))
 917                         goto out;
 918                 r = kvm_vm_ioctl_assign_device(kvm, &assigned_dev);
 919                 if (r)
 920                         goto out;
 921                 break;
 922         }
 923         case KVM_ASSIGN_IRQ: {
 924                 r = -EOPNOTSUPP;
 925                 break;
 926         }
 927         case KVM_ASSIGN_DEV_IRQ: {
 928                 struct kvm_assigned_irq assigned_irq;
 929
 930                 r = -EFAULT;
 931                 if (copy_from_user(&assigned_irq, argp, sizeof assigned_irq))
 932                         goto out;
 933                 r = kvm_vm_ioctl_assign_irq(kvm, &assigned_irq);
 934                 if (r)
 935                         goto out;
 936                 break;
 937         }
 938         case KVM_DEASSIGN_DEV_IRQ: {
 939                 struct kvm_assigned_irq assigned_irq;
 940
 941                 r = -EFAULT;
 942                 if (copy_from_user(&assigned_irq, argp, sizeof assigned_irq))
 943                         goto out;
 944                 r = kvm_vm_ioctl_deassign_dev_irq(kvm, &assigned_irq);
 945                 if (r)
 946                         goto out;
 947                 break;
 948         }
 949         case KVM_DEASSIGN_PCI_DEVICE: {
 950                 struct kvm_assigned_pci_dev assigned_dev;
 951
 952                 r = -EFAULT;
 953                 if (copy_from_user(&assigned_dev, argp, sizeof assigned_dev))
 954                         goto out;
 955                 r = kvm_vm_ioctl_deassign_device(kvm, &assigned_dev);
 956                 if (r)
 957                         goto out;
 958                 break;
 959         }
 960 #ifdef KVM_CAP_IRQ_ROUTING
 961         case KVM_SET_GSI_ROUTING: {
 962                 struct kvm_irq_routing routing;
 963                 struct kvm_irq_routing __user *urouting;
 964                 struct kvm_irq_routing_entry *entries;
 965
 966                 r = -EFAULT;
 967                 if (copy_from_user(&routing, argp, sizeof(routing)))
 968                         goto out;
 969                 r = -EINVAL;
 970                 if (routing.nr >= KVM_MAX_IRQ_ROUTES)
 971                         goto out;
 972                 if (routing.flags)
 973                         goto out;
 974                 r = -ENOMEM;
 975                 entries = vmalloc(routing.nr * sizeof(*entries));
 976                 if (!entries)
 977                         goto out;
 978                 r = -EFAULT;
 979                 urouting = argp;
 980                 if (copy_from_user(entries, urouting->entries,
 981                                    routing.nr * sizeof(*entries)))
 982                         goto out_free_irq_routing;
 983                 r = kvm_set_irq_routing(kvm, entries, routing.nr,
 984                                         routing.flags);
 985         out_free_irq_routing:
 986                 vfree(entries);
 987                 break;
 988         }
 989 #endif /* KVM_CAP_IRQ_ROUTING */
 990 #ifdef __KVM_HAVE_MSIX
 991         case KVM_ASSIGN_SET_MSIX_NR: {
 992                 struct kvm_assigned_msix_nr entry_nr;
 993                 r = -EFAULT;
 994                 if (copy_from_user(&entry_nr, argp, sizeof entry_nr))
 995                         goto out;
 996                 r = kvm_vm_ioctl_set_msix_nr(kvm, &entry_nr);
 997                 if (r)
 998                         goto out;
 999                 break;
1000         }
1001         case KVM_ASSIGN_SET_MSIX_ENTRY: {
1002                 struct kvm_assigned_msix_entry entry;
1003                 r = -EFAULT;
1004                 if (copy_from_user(&entry, argp, sizeof entry))
1005                         goto out;
1006                 r = kvm_vm_ioctl_set_msix_entry(kvm, &entry);
1007                 if (r)
1008                         goto out;
1009                 break;
1010         }
1011 #endif
1012         case KVM_ASSIGN_SET_INTX_MASK: {
1013                 struct kvm_assigned_pci_dev assigned_dev;
1014
1015                 r = -EFAULT;
1016                 if (copy_from_user(&assigned_dev, argp, sizeof assigned_dev))
1017                         goto out;
1018                 r = kvm_vm_ioctl_set_pci_irq_mask(kvm, &assigned_dev);
1019                 break;
1020         }
1021         default:
1022                 r = -ENOTTY;
1023                 break;
1024         }
1025 out:
1026         return r;
1027 }