kernel/drivers/xen/xen-pciback/pci_stub.c

   1 /*
   2  * PCI Stub Driver - Grabs devices in backend to be exported later
   3  *
   4  * Ryan Wilson <hap9@epoch.ncsc.mil>
   5  * Chris Bookholt <hap10@epoch.ncsc.mil>
   6  */
   7
   8 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
   9
  10 #include <linux/module.h>
  11 #include <linux/init.h>
  12 #include <linux/rwsem.h>
  13 #include <linux/list.h>
  14 #include <linux/spinlock.h>
  15 #include <linux/kref.h>
  16 #include <linux/pci.h>
  17 #include <linux/wait.h>
  18 #include <linux/sched.h>
  19 #include <linux/atomic.h>
  20 #include <xen/events.h>
  21 #include <asm/xen/pci.h>
  22 #include <asm/xen/hypervisor.h>
  23 #include <xen/interface/physdev.h>
  24 #include "pciback.h"
  25 #include "conf_space.h"
  26 #include "conf_space_quirks.h"
  27
  28 static char *pci_devs_to_hide;
  29 wait_queue_head_t xen_pcibk_aer_wait_queue;
  30 /*Add sem for sync AER handling and xen_pcibk remove/reconfigue ops,
  31 * We want to avoid in middle of AER ops, xen_pcibk devices is being removed
  32 */
  33 static DECLARE_RWSEM(pcistub_sem);
  34 module_param_named(hide, pci_devs_to_hide, charp, 0444);
  35
  36 struct pcistub_device_id {
  37         struct list_head slot_list;
  38         int domain;
  39         unsigned char bus;
  40         unsigned int devfn;
  41 };
  42 static LIST_HEAD(pcistub_device_ids);
  43 static DEFINE_SPINLOCK(device_ids_lock);
  44
  45 struct pcistub_device {
  46         struct kref kref;
  47         struct list_head dev_list;
  48         spinlock_t lock;
  49
  50         struct pci_dev *dev;
  51         struct xen_pcibk_device *pdev;/* non-NULL if struct pci_dev is in use */
  52 };
  53
  54 /* Access to pcistub_devices & seized_devices lists and the initialize_devices
  55  * flag must be locked with pcistub_devices_lock
  56  */
  57 static DEFINE_SPINLOCK(pcistub_devices_lock);
  58 static LIST_HEAD(pcistub_devices);
  59
  60 /* wait for device_initcall before initializing our devices
  61  * (see pcistub_init_devices_late)
  62  */
  63 static int initialize_devices;
  64 static LIST_HEAD(seized_devices);
  65
  66 static struct pcistub_device *pcistub_device_alloc(struct pci_dev *dev)
  67 {
  68         struct pcistub_device *psdev;
  69
  70         dev_dbg(&dev->dev, "pcistub_device_alloc\n");
  71
  72         psdev = kzalloc(sizeof(*psdev), GFP_ATOMIC);
  73         if (!psdev)
  74                 return NULL;
  75
  76         psdev->dev = pci_dev_get(dev);
  77         if (!psdev->dev) {
  78                 kfree(psdev);
  79                 return NULL;
  80         }
  81
  82         kref_init(&psdev->kref);
  83         spin_lock_init(&psdev->lock);
  84
  85         return psdev;
  86 }
  87
  88 /* Don't call this directly as it's called by pcistub_device_put */
  89 static void pcistub_device_release(struct kref *kref)
  90 {
  91         struct pcistub_device *psdev;
  92         struct pci_dev *dev;
  93         struct xen_pcibk_dev_data *dev_data;
  94
  95         psdev = container_of(kref, struct pcistub_device, kref);
  96         dev = psdev->dev;
  97         dev_data = pci_get_drvdata(dev);
  98
  99         dev_dbg(&dev->dev, "pcistub_device_release\n");
 100
 101         xen_unregister_device_domain_owner(dev);
 102
 103         /* Call the reset function which does not take lock as this
 104          * is called from "unbind" which takes a device_lock mutex.
 105          */
 106         __pci_reset_function_locked(dev);
 107         if (pci_load_and_free_saved_state(dev, &dev_data->pci_saved_state))
 108                 dev_info(&dev->dev, "Could not reload PCI state\n");
 109         else
 110                 pci_restore_state(dev);
 111
 112         if (dev->msix_cap) {
 113                 struct physdev_pci_device ppdev = {
 114                         .seg = pci_domain_nr(dev->bus),
 115                         .bus = dev->bus->number,
 116                         .devfn = dev->devfn
 117                 };
 118                 int err = HYPERVISOR_physdev_op(PHYSDEVOP_release_msix,
 119                                                 &ppdev);
 120
 121                 if (err && err != -ENOSYS)
 122                         dev_warn(&dev->dev, "MSI-X release failed (%d)\n",
 123                                  err);
 124         }
 125
 126         /* Disable the device */
 127         xen_pcibk_reset_device(dev);
 128
 129         kfree(dev_data);
 130         pci_set_drvdata(dev, NULL);
 131
 132         /* Clean-up the device */
 133         xen_pcibk_config_free_dyn_fields(dev);
 134         xen_pcibk_config_free_dev(dev);
 135
 136         pci_clear_dev_assigned(dev);
 137         pci_dev_put(dev);
 138
 139         kfree(psdev);
 140 }
 141
 142 static inline void pcistub_device_get(struct pcistub_device *psdev)
 143 {
 144         kref_get(&psdev->kref);
 145 }
 146
 147 static inline void pcistub_device_put(struct pcistub_device *psdev)
 148 {
 149         kref_put(&psdev->kref, pcistub_device_release);
 150 }
 151
 152 static struct pcistub_device *pcistub_device_find(int domain, int bus,
 153                                                   int slot, int func)
 154 {
 155         struct pcistub_device *psdev = NULL;
 156         unsigned long flags;
 157
 158         spin_lock_irqsave(&pcistub_devices_lock, flags);
 159
 160         list_for_each_entry(psdev, &pcistub_devices, dev_list) {
 161                 if (psdev->dev != NULL
 162                     && domain == pci_domain_nr(psdev->dev->bus)
 163                     && bus == psdev->dev->bus->number
 164                     && slot == PCI_SLOT(psdev->dev->devfn)
 165                     && func == PCI_FUNC(psdev->dev->devfn)) {
 166                         pcistub_device_get(psdev);
 167                         goto out;
 168                 }
 169         }
 170
 171         /* didn't find it */
 172         psdev = NULL;
 173
 174 out:
 175         spin_unlock_irqrestore(&pcistub_devices_lock, flags);
 176         return psdev;
 177 }
 178
 179 static struct pci_dev *pcistub_device_get_pci_dev(struct xen_pcibk_device *pdev,
 180                                                   struct pcistub_device *psdev)
 181 {
 182         struct pci_dev *pci_dev = NULL;
 183         unsigned long flags;
 184
 185         pcistub_device_get(psdev);
 186
 187         spin_lock_irqsave(&psdev->lock, flags);
 188         if (!psdev->pdev) {
 189                 psdev->pdev = pdev;
 190                 pci_dev = psdev->dev;
 191         }
 192         spin_unlock_irqrestore(&psdev->lock, flags);
 193
 194         if (!pci_dev)
 195                 pcistub_device_put(psdev);
 196
 197         return pci_dev;
 198 }
 199
 200 struct pci_dev *pcistub_get_pci_dev_by_slot(struct xen_pcibk_device *pdev,
 201                                             int domain, int bus,
 202                                             int slot, int func)
 203 {
 204         struct pcistub_device *psdev;
 205         struct pci_dev *found_dev = NULL;
 206         unsigned long flags;
 207
 208         spin_lock_irqsave(&pcistub_devices_lock, flags);
 209
 210         list_for_each_entry(psdev, &pcistub_devices, dev_list) {
 211                 if (psdev->dev != NULL
 212                     && domain == pci_domain_nr(psdev->dev->bus)
 213                     && bus == psdev->dev->bus->number
 214                     && slot == PCI_SLOT(psdev->dev->devfn)
 215                     && func == PCI_FUNC(psdev->dev->devfn)) {
 216                         found_dev = pcistub_device_get_pci_dev(pdev, psdev);
 217                         break;
 218                 }
 219         }
 220
 221         spin_unlock_irqrestore(&pcistub_devices_lock, flags);
 222         return found_dev;
 223 }
 224
 225 struct pci_dev *pcistub_get_pci_dev(struct xen_pcibk_device *pdev,
 226                                     struct pci_dev *dev)
 227 {
 228         struct pcistub_device *psdev;
 229         struct pci_dev *found_dev = NULL;
 230         unsigned long flags;
 231
 232         spin_lock_irqsave(&pcistub_devices_lock, flags);
 233
 234         list_for_each_entry(psdev, &pcistub_devices, dev_list) {
 235                 if (psdev->dev == dev) {
 236                         found_dev = pcistub_device_get_pci_dev(pdev, psdev);
 237                         break;
 238                 }
 239         }
 240
 241         spin_unlock_irqrestore(&pcistub_devices_lock, flags);
 242         return found_dev;
 243 }
 244
 245 /*
 246  * Called when:
 247  *  - XenBus state has been reconfigure (pci unplug). See xen_pcibk_remove_device
 248  *  - XenBus state has been disconnected (guest shutdown). See xen_pcibk_xenbus_remove
 249  *  - 'echo BDF > unbind' on pciback module with no guest attached. See pcistub_remove
 250  *  - 'echo BDF > unbind' with a guest still using it. See pcistub_remove
 251  *
 252  *  As such we have to be careful.
 253  *
 254  *  To make this easier, the caller has to hold the device lock.
 255  */
 256 void pcistub_put_pci_dev(struct pci_dev *dev)
 257 {
 258         struct pcistub_device *psdev, *found_psdev = NULL;
 259         unsigned long flags;
 260         struct xen_pcibk_dev_data *dev_data;
 261         int ret;
 262
 263         spin_lock_irqsave(&pcistub_devices_lock, flags);
 264
 265         list_for_each_entry(psdev, &pcistub_devices, dev_list) {
 266                 if (psdev->dev == dev) {
 267                         found_psdev = psdev;
 268                         break;
 269                 }
 270         }
 271
 272         spin_unlock_irqrestore(&pcistub_devices_lock, flags);
 273         if (WARN_ON(!found_psdev))
 274                 return;
 275
 276         /*hold this lock for avoiding breaking link between
 277         * pcistub and xen_pcibk when AER is in processing
 278         */
 279         down_write(&pcistub_sem);
 280         /* Cleanup our device
 281          * (so it's ready for the next domain)
 282          */
 283         device_lock_assert(&dev->dev);
 284         __pci_reset_function_locked(dev);
 285
 286         dev_data = pci_get_drvdata(dev);
 287         ret = pci_load_saved_state(dev, dev_data->pci_saved_state);
 288         if (!ret) {
 289                 /*
 290                  * The usual sequence is pci_save_state & pci_restore_state
 291                  * but the guest might have messed the configuration space up.
 292                  * Use the initial version (when device was bound to us).
 293                  */
 294                 pci_restore_state(dev);
 295         } else
 296                 dev_info(&dev->dev, "Could not reload PCI state\n");
 297         /* This disables the device. */
 298         xen_pcibk_reset_device(dev);
 299
 300         /* And cleanup up our emulated fields. */
 301         xen_pcibk_config_reset_dev(dev);
 302         xen_pcibk_config_free_dyn_fields(dev);
 303
 304         xen_unregister_device_domain_owner(dev);
 305
 306         spin_lock_irqsave(&found_psdev->lock, flags);
 307         found_psdev->pdev = NULL;
 308         spin_unlock_irqrestore(&found_psdev->lock, flags);
 309
 310         pcistub_device_put(found_psdev);
 311         up_write(&pcistub_sem);
 312 }
 313
 314 static int pcistub_match_one(struct pci_dev *dev,
 315                              struct pcistub_device_id *pdev_id)
 316 {
 317         /* Match the specified device by domain, bus, slot, func and also if
 318          * any of the device's parent bridges match.
 319          */
 320         for (; dev != NULL; dev = dev->bus->self) {
 321                 if (pci_domain_nr(dev->bus) == pdev_id->domain
 322                     && dev->bus->number == pdev_id->bus
 323                     && dev->devfn == pdev_id->devfn)
 324                         return 1;
 325
 326                 /* Sometimes topmost bridge links to itself. */
 327                 if (dev == dev->bus->self)
 328                         break;
 329         }
 330
 331         return 0;
 332 }
 333
 334 static int pcistub_match(struct pci_dev *dev)
 335 {
 336         struct pcistub_device_id *pdev_id;
 337         unsigned long flags;
 338         int found = 0;
 339
 340         spin_lock_irqsave(&device_ids_lock, flags);
 341         list_for_each_entry(pdev_id, &pcistub_device_ids, slot_list) {
 342                 if (pcistub_match_one(dev, pdev_id)) {
 343                         found = 1;
 344                         break;
 345                 }
 346         }
 347         spin_unlock_irqrestore(&device_ids_lock, flags);
 348
 349         return found;
 350 }
 351
 352 static int pcistub_init_device(struct pci_dev *dev)
 353 {
 354         struct xen_pcibk_dev_data *dev_data;
 355         int err = 0;
 356
 357         dev_dbg(&dev->dev, "initializing...\n");
 358
 359         /* The PCI backend is not intended to be a module (or to work with
 360          * removable PCI devices (yet). If it were, xen_pcibk_config_free()
 361          * would need to be called somewhere to free the memory allocated
 362          * here and then to call kfree(pci_get_drvdata(psdev->dev)).
 363          */
 364         dev_data = kzalloc(sizeof(*dev_data) +  strlen(DRV_NAME "[]")
 365                                 + strlen(pci_name(dev)) + 1, GFP_ATOMIC);
 366         if (!dev_data) {
 367                 err = -ENOMEM;
 368                 goto out;
 369         }
 370         pci_set_drvdata(dev, dev_data);
 371
 372         /*
 373          * Setup name for fake IRQ handler. It will only be enabled
 374          * once the device is turned on by the guest.
 375          */
 376         sprintf(dev_data->irq_name, DRV_NAME "[%s]", pci_name(dev));
 377
 378         dev_dbg(&dev->dev, "initializing config\n");
 379
 380         init_waitqueue_head(&xen_pcibk_aer_wait_queue);
 381         err = xen_pcibk_config_init_dev(dev);
 382         if (err)
 383                 goto out;
 384
 385         /* HACK: Force device (& ACPI) to determine what IRQ it's on - we
 386          * must do this here because pcibios_enable_device may specify
 387          * the pci device's true irq (and possibly its other resources)
 388          * if they differ from what's in the configuration space.
 389          * This makes the assumption that the device's resources won't
 390          * change after this point (otherwise this code may break!)
 391          */
 392         dev_dbg(&dev->dev, "enabling device\n");
 393         err = pci_enable_device(dev);
 394         if (err)
 395                 goto config_release;
 396
 397         if (dev->msix_cap) {
 398                 struct physdev_pci_device ppdev = {
 399                         .seg = pci_domain_nr(dev->bus),
 400                         .bus = dev->bus->number,
 401                         .devfn = dev->devfn
 402                 };
 403
 404                 err = HYPERVISOR_physdev_op(PHYSDEVOP_prepare_msix, &ppdev);
 405                 if (err && err != -ENOSYS)
 406                         dev_err(&dev->dev, "MSI-X preparation failed (%d)\n",
 407                                 err);
 408         }
 409
 410         /* We need the device active to save the state. */
 411         dev_dbg(&dev->dev, "save state of device\n");
 412         pci_save_state(dev);
 413         dev_data->pci_saved_state = pci_store_saved_state(dev);
 414         if (!dev_data->pci_saved_state)
 415                 dev_err(&dev->dev, "Could not store PCI conf saved state!\n");
 416         else {
 417                 dev_dbg(&dev->dev, "resetting (FLR, D3, etc) the device\n");
 418                 __pci_reset_function_locked(dev);
 419                 pci_restore_state(dev);
 420         }
 421         /* Now disable the device (this also ensures some private device
 422          * data is setup before we export)
 423          */
 424         dev_dbg(&dev->dev, "reset device\n");
 425         xen_pcibk_reset_device(dev);
 426
 427         pci_set_dev_assigned(dev);
 428         return 0;
 429
 430 config_release:
 431         xen_pcibk_config_free_dev(dev);
 432
 433 out:
 434         pci_set_drvdata(dev, NULL);
 435         kfree(dev_data);
 436         return err;
 437 }
 438
 439 /*
 440  * Because some initialization still happens on
 441  * devices during fs_initcall, we need to defer
 442  * full initialization of our devices until
 443  * device_initcall.
 444  */
 445 static int __init pcistub_init_devices_late(void)
 446 {
 447         struct pcistub_device *psdev;
 448         unsigned long flags;
 449         int err = 0;
 450
 451         spin_lock_irqsave(&pcistub_devices_lock, flags);
 452
 453         while (!list_empty(&seized_devices)) {
 454                 psdev = container_of(seized_devices.next,
 455                                      struct pcistub_device, dev_list);
 456                 list_del(&psdev->dev_list);
 457
 458                 spin_unlock_irqrestore(&pcistub_devices_lock, flags);
 459
 460                 err = pcistub_init_device(psdev->dev);
 461                 if (err) {
 462                         dev_err(&psdev->dev->dev,
 463                                 "error %d initializing device\n", err);
 464                         kfree(psdev);
 465                         psdev = NULL;
 466                 }
 467
 468                 spin_lock_irqsave(&pcistub_devices_lock, flags);
 469
 470                 if (psdev)
 471                         list_add_tail(&psdev->dev_list, &pcistub_devices);
 472         }
 473
 474         initialize_devices = 1;
 475
 476         spin_unlock_irqrestore(&pcistub_devices_lock, flags);
 477
 478         return 0;
 479 }
 480
 481 static int pcistub_seize(struct pci_dev *dev)
 482 {
 483         struct pcistub_device *psdev;
 484         unsigned long flags;
 485         int err = 0;
 486
 487         psdev = pcistub_device_alloc(dev);
 488         if (!psdev)
 489                 return -ENOMEM;
 490
 491         spin_lock_irqsave(&pcistub_devices_lock, flags);
 492
 493         if (initialize_devices) {
 494                 spin_unlock_irqrestore(&pcistub_devices_lock, flags);
 495
 496                 /* don't want irqs disabled when calling pcistub_init_device */
 497                 err = pcistub_init_device(psdev->dev);
 498
 499                 spin_lock_irqsave(&pcistub_devices_lock, flags);
 500
 501                 if (!err)
 502                         list_add(&psdev->dev_list, &pcistub_devices);
 503         } else {
 504                 dev_dbg(&dev->dev, "deferring initialization\n");
 505                 list_add(&psdev->dev_list, &seized_devices);
 506         }
 507
 508         spin_unlock_irqrestore(&pcistub_devices_lock, flags);
 509
 510         if (err)
 511                 pcistub_device_put(psdev);
 512
 513         return err;
 514 }
 515
 516 /* Called when 'bind'. This means we must _NOT_ call pci_reset_function or
 517  * other functions that take the sysfs lock. */
 518 static int pcistub_probe(struct pci_dev *dev, const struct pci_device_id *id)
 519 {
 520         int err = 0;
 521
 522         dev_dbg(&dev->dev, "probing...\n");
 523
 524         if (pcistub_match(dev)) {
 525
 526                 if (dev->hdr_type != PCI_HEADER_TYPE_NORMAL
 527                     && dev->hdr_type != PCI_HEADER_TYPE_BRIDGE) {
 528                         dev_err(&dev->dev, "can't export pci devices that "
 529                                 "don't have a normal (0) or bridge (1) "
 530                                 "header type!\n");
 531                         err = -ENODEV;
 532                         goto out;
 533                 }
 534
 535                 dev_info(&dev->dev, "seizing device\n");
 536                 err = pcistub_seize(dev);
 537         } else
 538                 /* Didn't find the device */
 539                 err = -ENODEV;
 540
 541 out:
 542         return err;
 543 }
 544
 545 /* Called when 'unbind'. This means we must _NOT_ call pci_reset_function or
 546  * other functions that take the sysfs lock. */
 547 static void pcistub_remove(struct pci_dev *dev)
 548 {
 549         struct pcistub_device *psdev, *found_psdev = NULL;
 550         unsigned long flags;
 551
 552         dev_dbg(&dev->dev, "removing\n");
 553
 554         spin_lock_irqsave(&pcistub_devices_lock, flags);
 555
 556         xen_pcibk_config_quirk_release(dev);
 557
 558         list_for_each_entry(psdev, &pcistub_devices, dev_list) {
 559                 if (psdev->dev == dev) {
 560                         found_psdev = psdev;
 561                         break;
 562                 }
 563         }
 564
 565         spin_unlock_irqrestore(&pcistub_devices_lock, flags);
 566
 567         if (found_psdev) {
 568                 dev_dbg(&dev->dev, "found device to remove %s\n",
 569                         found_psdev->pdev ? "- in-use" : "");
 570
 571                 if (found_psdev->pdev) {
 572                         int domid = xen_find_device_domain_owner(dev);
 573
 574                         pr_warn("****** removing device %s while still in-use by domain %d! ******\n",
 575                                pci_name(found_psdev->dev), domid);
 576                         pr_warn("****** driver domain may still access this device's i/o resources!\n");
 577                         pr_warn("****** shutdown driver domain before binding device\n");
 578                         pr_warn("****** to other drivers or domains\n");
 579
 580                         /* N.B. This ends up calling pcistub_put_pci_dev which ends up
 581                          * doing the FLR. */
 582                         xen_pcibk_release_pci_dev(found_psdev->pdev,
 583                                                 found_psdev->dev,
 584                                                 false /* caller holds the lock. */);
 585                 }
 586
 587                 spin_lock_irqsave(&pcistub_devices_lock, flags);
 588                 list_del(&found_psdev->dev_list);
 589                 spin_unlock_irqrestore(&pcistub_devices_lock, flags);
 590
 591                 /* the final put for releasing from the list */
 592                 pcistub_device_put(found_psdev);
 593         }
 594 }
 595
 596 static const struct pci_device_id pcistub_ids[] = {
 597         {
 598          .vendor = PCI_ANY_ID,
 599          .device = PCI_ANY_ID,
 600          .subvendor = PCI_ANY_ID,
 601          .subdevice = PCI_ANY_ID,
 602          },
 603         {0,},
 604 };
 605
 606 #define PCI_NODENAME_MAX 40
 607 static void kill_domain_by_device(struct pcistub_device *psdev)
 608 {
 609         struct xenbus_transaction xbt;
 610         int err;
 611         char nodename[PCI_NODENAME_MAX];
 612
 613         BUG_ON(!psdev);
 614         snprintf(nodename, PCI_NODENAME_MAX, "/local/domain/0/backend/pci/%d/0",
 615                 psdev->pdev->xdev->otherend_id);
 616
 617 again:
 618         err = xenbus_transaction_start(&xbt);
 619         if (err) {
 620                 dev_err(&psdev->dev->dev,
 621                         "error %d when start xenbus transaction\n", err);
 622                 return;
 623         }
 624         /*PV AER handlers will set this flag*/
 625         xenbus_printf(xbt, nodename, "aerState" , "aerfail");
 626         err = xenbus_transaction_end(xbt, 0);
 627         if (err) {
 628                 if (err == -EAGAIN)
 629                         goto again;
 630                 dev_err(&psdev->dev->dev,
 631                         "error %d when end xenbus transaction\n", err);
 632                 return;
 633         }
 634 }
 635
 636 /* For each aer recovery step error_detected, mmio_enabled, etc, front_end and
 637  * backend need to have cooperation. In xen_pcibk, those steps will do similar
 638  * jobs: send service request and waiting for front_end response.
 639 */
 640 static pci_ers_result_t common_process(struct pcistub_device *psdev,
 641                                        pci_channel_state_t state, int aer_cmd,
 642                                        pci_ers_result_t result)
 643 {
 644         pci_ers_result_t res = result;
 645         struct xen_pcie_aer_op *aer_op;
 646         struct xen_pcibk_device *pdev = psdev->pdev;
 647         struct xen_pci_sharedinfo *sh_info = pdev->sh_info;
 648         int ret;
 649
 650         /*with PV AER drivers*/
 651         aer_op = &(sh_info->aer_op);
 652         aer_op->cmd = aer_cmd ;
 653         /*useful for error_detected callback*/
 654         aer_op->err = state;
 655         /*pcifront_end BDF*/
 656         ret = xen_pcibk_get_pcifront_dev(psdev->dev, psdev->pdev,
 657                 &aer_op->domain, &aer_op->bus, &aer_op->devfn);
 658         if (!ret) {
 659                 dev_err(&psdev->dev->dev,
 660                         DRV_NAME ": failed to get pcifront device\n");
 661                 return PCI_ERS_RESULT_NONE;
 662         }
 663         wmb();
 664
 665         dev_dbg(&psdev->dev->dev,
 666                         DRV_NAME ": aer_op %x dom %x bus %x devfn %x\n",
 667                         aer_cmd, aer_op->domain, aer_op->bus, aer_op->devfn);
 668         /*local flag to mark there's aer request, xen_pcibk callback will use
 669         * this flag to judge whether we need to check pci-front give aer
 670         * service ack signal
 671         */
 672         set_bit(_PCIB_op_pending, (unsigned long *)&pdev->flags);
 673
 674         /*It is possible that a pcifront conf_read_write ops request invokes
 675         * the callback which cause the spurious execution of wake_up.
 676         * Yet it is harmless and better than a spinlock here
 677         */
 678         set_bit(_XEN_PCIB_active,
 679                 (unsigned long *)&sh_info->flags);
 680         wmb();
 681         notify_remote_via_irq(pdev->evtchn_irq);
 682
 683         ret = wait_event_timeout(xen_pcibk_aer_wait_queue,
 684                                  !(test_bit(_XEN_PCIB_active, (unsigned long *)
 685                                  &sh_info->flags)), 300*HZ);
 686
 687         if (!ret) {
 688                 if (test_bit(_XEN_PCIB_active,
 689                         (unsigned long *)&sh_info->flags)) {
 690                         dev_err(&psdev->dev->dev,
 691                                 "pcifront aer process not responding!\n");
 692                         clear_bit(_XEN_PCIB_active,
 693                           (unsigned long *)&sh_info->flags);
 694                         aer_op->err = PCI_ERS_RESULT_NONE;
 695                         return res;
 696                 }
 697         }
 698         clear_bit(_PCIB_op_pending, (unsigned long *)&pdev->flags);
 699
 700         if (test_bit(_XEN_PCIF_active,
 701                 (unsigned long *)&sh_info->flags)) {
 702                 dev_dbg(&psdev->dev->dev,
 703                         "schedule pci_conf service in " DRV_NAME "\n");
 704                 xen_pcibk_test_and_schedule_op(psdev->pdev);
 705         }
 706
 707         res = (pci_ers_result_t)aer_op->err;
 708         return res;
 709 }
 710
 711 /*
 712 * xen_pcibk_slot_reset: it will send the slot_reset request to  pcifront in case
 713 * of the device driver could provide this service, and then wait for pcifront
 714 * ack.
 715 * @dev: pointer to PCI devices
 716 * return value is used by aer_core do_recovery policy
 717 */
 718 static pci_ers_result_t xen_pcibk_slot_reset(struct pci_dev *dev)
 719 {
 720         struct pcistub_device *psdev;
 721         pci_ers_result_t result;
 722
 723         result = PCI_ERS_RESULT_RECOVERED;
 724         dev_dbg(&dev->dev, "xen_pcibk_slot_reset(bus:%x,devfn:%x)\n",
 725                 dev->bus->number, dev->devfn);
 726
 727         down_write(&pcistub_sem);
 728         psdev = pcistub_device_find(pci_domain_nr(dev->bus),
 729                                 dev->bus->number,
 730                                 PCI_SLOT(dev->devfn),
 731                                 PCI_FUNC(dev->devfn));
 732
 733         if (!psdev || !psdev->pdev) {
 734                 dev_err(&dev->dev,
 735                         DRV_NAME " device is not found/assigned\n");
 736                 goto end;
 737         }
 738
 739         if (!psdev->pdev->sh_info) {
 740                 dev_err(&dev->dev, DRV_NAME " device is not connected or owned"
 741                         " by HVM, kill it\n");
 742                 kill_domain_by_device(psdev);
 743                 goto end;
 744         }
 745
 746         if (!test_bit(_XEN_PCIB_AERHANDLER,
 747                 (unsigned long *)&psdev->pdev->sh_info->flags)) {
 748                 dev_err(&dev->dev,
 749                         "guest with no AER driver should have been killed\n");
 750                 goto end;
 751         }
 752         result = common_process(psdev, 1, XEN_PCI_OP_aer_slotreset, result);
 753
 754         if (result == PCI_ERS_RESULT_NONE ||
 755                 result == PCI_ERS_RESULT_DISCONNECT) {
 756                 dev_dbg(&dev->dev,
 757                         "No AER slot_reset service or disconnected!\n");
 758                 kill_domain_by_device(psdev);
 759         }
 760 end:
 761         if (psdev)
 762                 pcistub_device_put(psdev);
 763         up_write(&pcistub_sem);
 764         return result;
 765
 766 }
 767
 768
 769 /*xen_pcibk_mmio_enabled: it will send the mmio_enabled request to  pcifront
 770 * in case of the device driver could provide this service, and then wait
 771 * for pcifront ack
 772 * @dev: pointer to PCI devices
 773 * return value is used by aer_core do_recovery policy
 774 */
 775
 776 static pci_ers_result_t xen_pcibk_mmio_enabled(struct pci_dev *dev)
 777 {
 778         struct pcistub_device *psdev;
 779         pci_ers_result_t result;
 780
 781         result = PCI_ERS_RESULT_RECOVERED;
 782         dev_dbg(&dev->dev, "xen_pcibk_mmio_enabled(bus:%x,devfn:%x)\n",
 783                 dev->bus->number, dev->devfn);
 784
 785         down_write(&pcistub_sem);
 786         psdev = pcistub_device_find(pci_domain_nr(dev->bus),
 787                                 dev->bus->number,
 788                                 PCI_SLOT(dev->devfn),
 789                                 PCI_FUNC(dev->devfn));
 790
 791         if (!psdev || !psdev->pdev) {
 792                 dev_err(&dev->dev,
 793                         DRV_NAME " device is not found/assigned\n");
 794                 goto end;
 795         }
 796
 797         if (!psdev->pdev->sh_info) {
 798                 dev_err(&dev->dev, DRV_NAME " device is not connected or owned"
 799                         " by HVM, kill it\n");
 800                 kill_domain_by_device(psdev);
 801                 goto end;
 802         }
 803
 804         if (!test_bit(_XEN_PCIB_AERHANDLER,
 805                 (unsigned long *)&psdev->pdev->sh_info->flags)) {
 806                 dev_err(&dev->dev,
 807                         "guest with no AER driver should have been killed\n");
 808                 goto end;
 809         }
 810         result = common_process(psdev, 1, XEN_PCI_OP_aer_mmio, result);
 811
 812         if (result == PCI_ERS_RESULT_NONE ||
 813                 result == PCI_ERS_RESULT_DISCONNECT) {
 814                 dev_dbg(&dev->dev,
 815                         "No AER mmio_enabled service or disconnected!\n");
 816                 kill_domain_by_device(psdev);
 817         }
 818 end:
 819         if (psdev)
 820                 pcistub_device_put(psdev);
 821         up_write(&pcistub_sem);
 822         return result;
 823 }
 824
 825 /*xen_pcibk_error_detected: it will send the error_detected request to  pcifront
 826 * in case of the device driver could provide this service, and then wait
 827 * for pcifront ack.
 828 * @dev: pointer to PCI devices
 829 * @error: the current PCI connection state
 830 * return value is used by aer_core do_recovery policy
 831 */
 832
 833 static pci_ers_result_t xen_pcibk_error_detected(struct pci_dev *dev,
 834         pci_channel_state_t error)
 835 {
 836         struct pcistub_device *psdev;
 837         pci_ers_result_t result;
 838
 839         result = PCI_ERS_RESULT_CAN_RECOVER;
 840         dev_dbg(&dev->dev, "xen_pcibk_error_detected(bus:%x,devfn:%x)\n",
 841                 dev->bus->number, dev->devfn);
 842
 843         down_write(&pcistub_sem);
 844         psdev = pcistub_device_find(pci_domain_nr(dev->bus),
 845                                 dev->bus->number,
 846                                 PCI_SLOT(dev->devfn),
 847                                 PCI_FUNC(dev->devfn));
 848
 849         if (!psdev || !psdev->pdev) {
 850                 dev_err(&dev->dev,
 851                         DRV_NAME " device is not found/assigned\n");
 852                 goto end;
 853         }
 854
 855         if (!psdev->pdev->sh_info) {
 856                 dev_err(&dev->dev, DRV_NAME " device is not connected or owned"
 857                         " by HVM, kill it\n");
 858                 kill_domain_by_device(psdev);
 859                 goto end;
 860         }
 861
 862         /*Guest owns the device yet no aer handler regiested, kill guest*/
 863         if (!test_bit(_XEN_PCIB_AERHANDLER,
 864                 (unsigned long *)&psdev->pdev->sh_info->flags)) {
 865                 dev_dbg(&dev->dev, "guest may have no aer driver, kill it\n");
 866                 kill_domain_by_device(psdev);
 867                 goto end;
 868         }
 869         result = common_process(psdev, error, XEN_PCI_OP_aer_detected, result);
 870
 871         if (result == PCI_ERS_RESULT_NONE ||
 872                 result == PCI_ERS_RESULT_DISCONNECT) {
 873                 dev_dbg(&dev->dev,
 874                         "No AER error_detected service or disconnected!\n");
 875                 kill_domain_by_device(psdev);
 876         }
 877 end:
 878         if (psdev)
 879                 pcistub_device_put(psdev);
 880         up_write(&pcistub_sem);
 881         return result;
 882 }
 883
 884 /*xen_pcibk_error_resume: it will send the error_resume request to  pcifront
 885 * in case of the device driver could provide this service, and then wait
 886 * for pcifront ack.
 887 * @dev: pointer to PCI devices
 888 */
 889
 890 static void xen_pcibk_error_resume(struct pci_dev *dev)
 891 {
 892         struct pcistub_device *psdev;
 893
 894         dev_dbg(&dev->dev, "xen_pcibk_error_resume(bus:%x,devfn:%x)\n",
 895                 dev->bus->number, dev->devfn);
 896
 897         down_write(&pcistub_sem);
 898         psdev = pcistub_device_find(pci_domain_nr(dev->bus),
 899                                 dev->bus->number,
 900                                 PCI_SLOT(dev->devfn),
 901                                 PCI_FUNC(dev->devfn));
 902
 903         if (!psdev || !psdev->pdev) {
 904                 dev_err(&dev->dev,
 905                         DRV_NAME " device is not found/assigned\n");
 906                 goto end;
 907         }
 908
 909         if (!psdev->pdev->sh_info) {
 910                 dev_err(&dev->dev, DRV_NAME " device is not connected or owned"
 911                         " by HVM, kill it\n");
 912                 kill_domain_by_device(psdev);
 913                 goto end;
 914         }
 915
 916         if (!test_bit(_XEN_PCIB_AERHANDLER,
 917                 (unsigned long *)&psdev->pdev->sh_info->flags)) {
 918                 dev_err(&dev->dev,
 919                         "guest with no AER driver should have been killed\n");
 920                 kill_domain_by_device(psdev);
 921                 goto end;
 922         }
 923         common_process(psdev, 1, XEN_PCI_OP_aer_resume,
 924                        PCI_ERS_RESULT_RECOVERED);
 925 end:
 926         if (psdev)
 927                 pcistub_device_put(psdev);
 928         up_write(&pcistub_sem);
 929         return;
 930 }
 931
 932 /*add xen_pcibk AER handling*/
 933 static const struct pci_error_handlers xen_pcibk_error_handler = {
 934         .error_detected = xen_pcibk_error_detected,
 935         .mmio_enabled = xen_pcibk_mmio_enabled,
 936         .slot_reset = xen_pcibk_slot_reset,
 937         .resume = xen_pcibk_error_resume,
 938 };
 939
 940 /*
 941  * Note: There is no MODULE_DEVICE_TABLE entry here because this isn't
 942  * for a normal device. I don't want it to be loaded automatically.
 943  */
 944
 945 static struct pci_driver xen_pcibk_pci_driver = {
 946         /* The name should be xen_pciback, but until the tools are updated
 947          * we will keep it as pciback. */
 948         .name = "pciback",
 949         .id_table = pcistub_ids,
 950         .probe = pcistub_probe,
 951         .remove = pcistub_remove,
 952         .err_handler = &xen_pcibk_error_handler,
 953 };
 954
 955 static inline int str_to_slot(const char *buf, int *domain, int *bus,
 956                               int *slot, int *func)
 957 {
 958         int parsed = 0;
 959
 960         switch (sscanf(buf, " %x:%x:%x.%x %n", domain, bus, slot, func,
 961                        &parsed)) {
 962         case 3:
 963                 *func = -1;
 964                 sscanf(buf, " %x:%x:%x.* %n", domain, bus, slot, &parsed);
 965                 break;
 966         case 2:
 967                 *slot = *func = -1;
 968                 sscanf(buf, " %x:%x:*.* %n", domain, bus, &parsed);
 969                 break;
 970         }
 971         if (parsed && !buf[parsed])
 972                 return 0;
 973
 974         /* try again without domain */
 975         *domain = 0;
 976         switch (sscanf(buf, " %x:%x.%x %n", bus, slot, func, &parsed)) {
 977         case 2:
 978                 *func = -1;
 979                 sscanf(buf, " %x:%x.* %n", bus, slot, &parsed);
 980                 break;
 981         case 1:
 982                 *slot = *func = -1;
 983                 sscanf(buf, " %x:*.* %n", bus, &parsed);
 984                 break;
 985         }
 986         if (parsed && !buf[parsed])
 987                 return 0;
 988
 989         return -EINVAL;
 990 }
 991
 992 static inline int str_to_quirk(const char *buf, int *domain, int *bus, int
 993                                *slot, int *func, int *reg, int *size, int *mask)
 994 {
 995         int parsed = 0;
 996
 997         sscanf(buf, " %x:%x:%x.%x-%x:%x:%x %n", domain, bus, slot, func,
 998                reg, size, mask, &parsed);
 999         if (parsed && !buf[parsed])
1000                 return 0;
1001
1002         /* try again without domain */
1003         *domain = 0;
1004         sscanf(buf, " %x:%x.%x-%x:%x:%x %n", bus, slot, func, reg, size,
1005                mask, &parsed);
1006         if (parsed && !buf[parsed])
1007                 return 0;
1008
1009         return -EINVAL;
1010 }
1011
1012 static int pcistub_device_id_add(int domain, int bus, int slot, int func)
1013 {
1014         struct pcistub_device_id *pci_dev_id;
1015         unsigned long flags;
1016         int rc = 0, devfn = PCI_DEVFN(slot, func);
1017
1018         if (slot < 0) {
1019                 for (slot = 0; !rc && slot < 32; ++slot)
1020                         rc = pcistub_device_id_add(domain, bus, slot, func);
1021                 return rc;
1022         }
1023
1024         if (func < 0) {
1025                 for (func = 0; !rc && func < 8; ++func)
1026                         rc = pcistub_device_id_add(domain, bus, slot, func);
1027                 return rc;
1028         }
1029
1030         if ((
1031 #if !defined(MODULE) /* pci_domains_supported is not being exported */ \
1032     || !defined(CONFIG_PCI_DOMAINS)
1033              !pci_domains_supported ? domain :
1034 #endif
1035              domain < 0 || domain > 0xffff)
1036             || bus < 0 || bus > 0xff
1037             || PCI_SLOT(devfn) != slot
1038             || PCI_FUNC(devfn) != func)
1039                 return -EINVAL;
1040
1041         pci_dev_id = kmalloc(sizeof(*pci_dev_id), GFP_KERNEL);
1042         if (!pci_dev_id)
1043                 return -ENOMEM;
1044
1045         pci_dev_id->domain = domain;
1046         pci_dev_id->bus = bus;
1047         pci_dev_id->devfn = devfn;
1048
1049         pr_debug("wants to seize %04x:%02x:%02x.%d\n",
1050                  domain, bus, slot, func);
1051
1052         spin_lock_irqsave(&device_ids_lock, flags);
1053         list_add_tail(&pci_dev_id->slot_list, &pcistub_device_ids);
1054         spin_unlock_irqrestore(&device_ids_lock, flags);
1055
1056         return 0;
1057 }
1058
1059 static int pcistub_device_id_remove(int domain, int bus, int slot, int func)
1060 {
1061         struct pcistub_device_id *pci_dev_id, *t;
1062         int err = -ENOENT;
1063         unsigned long flags;
1064
1065         spin_lock_irqsave(&device_ids_lock, flags);
1066         list_for_each_entry_safe(pci_dev_id, t, &pcistub_device_ids,
1067                                  slot_list) {
1068                 if (pci_dev_id->domain == domain && pci_dev_id->bus == bus
1069                     && (slot < 0 || PCI_SLOT(pci_dev_id->devfn) == slot)
1070                     && (func < 0 || PCI_FUNC(pci_dev_id->devfn) == func)) {
1071                         /* Don't break; here because it's possible the same
1072                          * slot could be in the list more than once
1073                          */
1074                         list_del(&pci_dev_id->slot_list);
1075                         kfree(pci_dev_id);
1076
1077                         err = 0;
1078
1079                         pr_debug("removed %04x:%02x:%02x.%d from seize list\n",
1080                                  domain, bus, slot, func);
1081                 }
1082         }
1083         spin_unlock_irqrestore(&device_ids_lock, flags);
1084
1085         return err;
1086 }
1087
1088 static int pcistub_reg_add(int domain, int bus, int slot, int func,
1089                            unsigned int reg, unsigned int size,
1090                            unsigned int mask)
1091 {
1092         int err = 0;
1093         struct pcistub_device *psdev;
1094         struct pci_dev *dev;
1095         struct config_field *field;
1096
1097         if (reg > 0xfff || (size < 4 && (mask >> (size * 8))))
1098                 return -EINVAL;
1099
1100         psdev = pcistub_device_find(domain, bus, slot, func);
1101         if (!psdev) {
1102                 err = -ENODEV;
1103                 goto out;
1104         }
1105         dev = psdev->dev;
1106
1107         field = kzalloc(sizeof(*field), GFP_ATOMIC);
1108         if (!field) {
1109                 err = -ENOMEM;
1110                 goto out;
1111         }
1112
1113         field->offset = reg;
1114         field->size = size;
1115         field->mask = mask;
1116         field->init = NULL;
1117         field->reset = NULL;
1118         field->release = NULL;
1119         field->clean = xen_pcibk_config_field_free;
1120
1121         err = xen_pcibk_config_quirks_add_field(dev, field);
1122         if (err)
1123                 kfree(field);
1124 out:
1125         if (psdev)
1126                 pcistub_device_put(psdev);
1127         return err;
1128 }
1129
1130 static ssize_t pcistub_slot_add(struct device_driver *drv, const char *buf,
1131                                 size_t count)
1132 {
1133         int domain, bus, slot, func;
1134         int err;
1135
1136         err = str_to_slot(buf, &domain, &bus, &slot, &func);
1137         if (err)
1138                 goto out;
1139
1140         err = pcistub_device_id_add(domain, bus, slot, func);
1141
1142 out:
1143         if (!err)
1144                 err = count;
1145         return err;
1146 }
1147 static DRIVER_ATTR(new_slot, S_IWUSR, NULL, pcistub_slot_add);
1148
1149 static ssize_t pcistub_slot_remove(struct device_driver *drv, const char *buf,
1150                                    size_t count)
1151 {
1152         int domain, bus, slot, func;
1153         int err;
1154
1155         err = str_to_slot(buf, &domain, &bus, &slot, &func);
1156         if (err)
1157                 goto out;
1158
1159         err = pcistub_device_id_remove(domain, bus, slot, func);
1160
1161 out:
1162         if (!err)
1163                 err = count;
1164         return err;
1165 }
1166 static DRIVER_ATTR(remove_slot, S_IWUSR, NULL, pcistub_slot_remove);
1167
1168 static ssize_t pcistub_slot_show(struct device_driver *drv, char *buf)
1169 {
1170         struct pcistub_device_id *pci_dev_id;
1171         size_t count = 0;
1172         unsigned long flags;
1173
1174         spin_lock_irqsave(&device_ids_lock, flags);
1175         list_for_each_entry(pci_dev_id, &pcistub_device_ids, slot_list) {
1176                 if (count >= PAGE_SIZE)
1177                         break;
1178
1179                 count += scnprintf(buf + count, PAGE_SIZE - count,
1180                                    "%04x:%02x:%02x.%d\n",
1181                                    pci_dev_id->domain, pci_dev_id->bus,
1182                                    PCI_SLOT(pci_dev_id->devfn),
1183                                    PCI_FUNC(pci_dev_id->devfn));
1184         }
1185         spin_unlock_irqrestore(&device_ids_lock, flags);
1186
1187         return count;
1188 }
1189 static DRIVER_ATTR(slots, S_IRUSR, pcistub_slot_show, NULL);
1190
1191 static ssize_t pcistub_irq_handler_show(struct device_driver *drv, char *buf)
1192 {
1193         struct pcistub_device *psdev;
1194         struct xen_pcibk_dev_data *dev_data;
1195         size_t count = 0;
1196         unsigned long flags;
1197
1198         spin_lock_irqsave(&pcistub_devices_lock, flags);
1199         list_for_each_entry(psdev, &pcistub_devices, dev_list) {
1200                 if (count >= PAGE_SIZE)
1201                         break;
1202                 if (!psdev->dev)
1203                         continue;
1204                 dev_data = pci_get_drvdata(psdev->dev);
1205                 if (!dev_data)
1206                         continue;
1207                 count +=
1208                     scnprintf(buf + count, PAGE_SIZE - count,
1209                               "%s:%s:%sing:%ld\n",
1210                               pci_name(psdev->dev),
1211                               dev_data->isr_on ? "on" : "off",
1212                               dev_data->ack_intr ? "ack" : "not ack",
1213                               dev_data->handled);
1214         }
1215         spin_unlock_irqrestore(&pcistub_devices_lock, flags);
1216         return count;
1217 }
1218 static DRIVER_ATTR(irq_handlers, S_IRUSR, pcistub_irq_handler_show, NULL);
1219
1220 static ssize_t pcistub_irq_handler_switch(struct device_driver *drv,
1221                                           const char *buf,
1222                                           size_t count)
1223 {
1224         struct pcistub_device *psdev;
1225         struct xen_pcibk_dev_data *dev_data;
1226         int domain, bus, slot, func;
1227         int err;
1228
1229         err = str_to_slot(buf, &domain, &bus, &slot, &func);
1230         if (err)
1231                 return err;
1232
1233         psdev = pcistub_device_find(domain, bus, slot, func);
1234         if (!psdev) {
1235                 err = -ENOENT;
1236                 goto out;
1237         }
1238
1239         dev_data = pci_get_drvdata(psdev->dev);
1240         if (!dev_data) {
1241                 err = -ENOENT;
1242                 goto out;
1243         }
1244
1245         dev_dbg(&psdev->dev->dev, "%s fake irq handler: %d->%d\n",
1246                 dev_data->irq_name, dev_data->isr_on,
1247                 !dev_data->isr_on);
1248
1249         dev_data->isr_on = !(dev_data->isr_on);
1250         if (dev_data->isr_on)
1251                 dev_data->ack_intr = 1;
1252 out:
1253         if (psdev)
1254                 pcistub_device_put(psdev);
1255         if (!err)
1256                 err = count;
1257         return err;
1258 }
1259 static DRIVER_ATTR(irq_handler_state, S_IWUSR, NULL,
1260                    pcistub_irq_handler_switch);
1261
1262 static ssize_t pcistub_quirk_add(struct device_driver *drv, const char *buf,
1263                                  size_t count)
1264 {
1265         int domain, bus, slot, func, reg, size, mask;
1266         int err;
1267
1268         err = str_to_quirk(buf, &domain, &bus, &slot, &func, &reg, &size,
1269                            &mask);
1270         if (err)
1271                 goto out;
1272
1273         err = pcistub_reg_add(domain, bus, slot, func, reg, size, mask);
1274
1275 out:
1276         if (!err)
1277                 err = count;
1278         return err;
1279 }
1280
1281 static ssize_t pcistub_quirk_show(struct device_driver *drv, char *buf)
1282 {
1283         int count = 0;
1284         unsigned long flags;
1285         struct xen_pcibk_config_quirk *quirk;
1286         struct xen_pcibk_dev_data *dev_data;
1287         const struct config_field *field;
1288         const struct config_field_entry *cfg_entry;
1289
1290         spin_lock_irqsave(&device_ids_lock, flags);
1291         list_for_each_entry(quirk, &xen_pcibk_quirks, quirks_list) {
1292                 if (count >= PAGE_SIZE)
1293                         goto out;
1294
1295                 count += scnprintf(buf + count, PAGE_SIZE - count,
1296                                    "%02x:%02x.%01x\n\t%04x:%04x:%04x:%04x\n",
1297                                    quirk->pdev->bus->number,
1298                                    PCI_SLOT(quirk->pdev->devfn),
1299                                    PCI_FUNC(quirk->pdev->devfn),
1300                                    quirk->devid.vendor, quirk->devid.device,
1301                                    quirk->devid.subvendor,
1302                                    quirk->devid.subdevice);
1303
1304                 dev_data = pci_get_drvdata(quirk->pdev);
1305
1306                 list_for_each_entry(cfg_entry, &dev_data->config_fields, list) {
1307                         field = cfg_entry->field;
1308                         if (count >= PAGE_SIZE)
1309                                 goto out;
1310
1311                         count += scnprintf(buf + count, PAGE_SIZE - count,
1312                                            "\t\t%08x:%01x:%08x\n",
1313                                            cfg_entry->base_offset +
1314                                            field->offset, field->size,
1315                                            field->mask);
1316                 }
1317         }
1318
1319 out:
1320         spin_unlock_irqrestore(&device_ids_lock, flags);
1321
1322         return count;
1323 }
1324 static DRIVER_ATTR(quirks, S_IRUSR | S_IWUSR, pcistub_quirk_show,
1325                    pcistub_quirk_add);
1326
1327 static ssize_t permissive_add(struct device_driver *drv, const char *buf,
1328                               size_t count)
1329 {
1330         int domain, bus, slot, func;
1331         int err;
1332         struct pcistub_device *psdev;
1333         struct xen_pcibk_dev_data *dev_data;
1334
1335         err = str_to_slot(buf, &domain, &bus, &slot, &func);
1336         if (err)
1337                 goto out;
1338
1339         psdev = pcistub_device_find(domain, bus, slot, func);
1340         if (!psdev) {
1341                 err = -ENODEV;
1342                 goto out;
1343         }
1344
1345         dev_data = pci_get_drvdata(psdev->dev);
1346         /* the driver data for a device should never be null at this point */
1347         if (!dev_data) {
1348                 err = -ENXIO;
1349                 goto release;
1350         }
1351         if (!dev_data->permissive) {
1352                 dev_data->permissive = 1;
1353                 /* Let user know that what they're doing could be unsafe */
1354                 dev_warn(&psdev->dev->dev, "enabling permissive mode "
1355                          "configuration space accesses!\n");
1356                 dev_warn(&psdev->dev->dev,
1357                          "permissive mode is potentially unsafe!\n");
1358         }
1359 release:
1360         pcistub_device_put(psdev);
1361 out:
1362         if (!err)
1363                 err = count;
1364         return err;
1365 }
1366
1367 static ssize_t permissive_show(struct device_driver *drv, char *buf)
1368 {
1369         struct pcistub_device *psdev;
1370         struct xen_pcibk_dev_data *dev_data;
1371         size_t count = 0;
1372         unsigned long flags;
1373         spin_lock_irqsave(&pcistub_devices_lock, flags);
1374         list_for_each_entry(psdev, &pcistub_devices, dev_list) {
1375                 if (count >= PAGE_SIZE)
1376                         break;
1377                 if (!psdev->dev)
1378                         continue;
1379                 dev_data = pci_get_drvdata(psdev->dev);
1380                 if (!dev_data || !dev_data->permissive)
1381                         continue;
1382                 count +=
1383                     scnprintf(buf + count, PAGE_SIZE - count, "%s\n",
1384                               pci_name(psdev->dev));
1385         }
1386         spin_unlock_irqrestore(&pcistub_devices_lock, flags);
1387         return count;
1388 }
1389 static DRIVER_ATTR(permissive, S_IRUSR | S_IWUSR, permissive_show,
1390                    permissive_add);
1391
1392 static void pcistub_exit(void)
1393 {
1394         driver_remove_file(&xen_pcibk_pci_driver.driver, &driver_attr_new_slot);
1395         driver_remove_file(&xen_pcibk_pci_driver.driver,
1396                            &driver_attr_remove_slot);
1397         driver_remove_file(&xen_pcibk_pci_driver.driver, &driver_attr_slots);
1398         driver_remove_file(&xen_pcibk_pci_driver.driver, &driver_attr_quirks);
1399         driver_remove_file(&xen_pcibk_pci_driver.driver,
1400                            &driver_attr_permissive);
1401         driver_remove_file(&xen_pcibk_pci_driver.driver,
1402                            &driver_attr_irq_handlers);
1403         driver_remove_file(&xen_pcibk_pci_driver.driver,
1404                            &driver_attr_irq_handler_state);
1405         pci_unregister_driver(&xen_pcibk_pci_driver);
1406 }
1407
1408 static int __init pcistub_init(void)
1409 {
1410         int pos = 0;
1411         int err = 0;
1412         int domain, bus, slot, func;
1413         int parsed;
1414
1415         if (pci_devs_to_hide && *pci_devs_to_hide) {
1416                 do {
1417                         parsed = 0;
1418
1419                         err = sscanf(pci_devs_to_hide + pos,
1420                                      " (%x:%x:%x.%x) %n",
1421                                      &domain, &bus, &slot, &func, &parsed);
1422                         switch (err) {
1423                         case 3:
1424                                 func = -1;
1425                                 sscanf(pci_devs_to_hide + pos,
1426                                        " (%x:%x:%x.*) %n",
1427                                        &domain, &bus, &slot, &parsed);
1428                                 break;
1429                         case 2:
1430                                 slot = func = -1;
1431                                 sscanf(pci_devs_to_hide + pos,
1432                                        " (%x:%x:*.*) %n",
1433                                        &domain, &bus, &parsed);
1434                                 break;
1435                         }
1436
1437                         if (!parsed) {
1438                                 domain = 0;
1439                                 err = sscanf(pci_devs_to_hide + pos,
1440                                              " (%x:%x.%x) %n",
1441                                              &bus, &slot, &func, &parsed);
1442                                 switch (err) {
1443                                 case 2:
1444                                         func = -1;
1445                                         sscanf(pci_devs_to_hide + pos,
1446                                                " (%x:%x.*) %n",
1447                                                &bus, &slot, &parsed);
1448                                         break;
1449                                 case 1:
1450                                         slot = func = -1;
1451                                         sscanf(pci_devs_to_hide + pos,
1452                                                " (%x:*.*) %n",
1453                                                &bus, &parsed);
1454                                         break;
1455                                 }
1456                         }
1457
1458                         if (parsed <= 0)
1459                                 goto parse_error;
1460
1461                         err = pcistub_device_id_add(domain, bus, slot, func);
1462                         if (err)
1463                                 goto out;
1464
1465                         pos += parsed;
1466                 } while (pci_devs_to_hide[pos]);
1467         }
1468
1469         /* If we're the first PCI Device Driver to register, we're the
1470          * first one to get offered PCI devices as they become
1471          * available (and thus we can be the first to grab them)
1472          */
1473         err = pci_register_driver(&xen_pcibk_pci_driver);
1474         if (err < 0)
1475                 goto out;
1476
1477         err = driver_create_file(&xen_pcibk_pci_driver.driver,
1478                                  &driver_attr_new_slot);
1479         if (!err)
1480                 err = driver_create_file(&xen_pcibk_pci_driver.driver,
1481                                          &driver_attr_remove_slot);
1482         if (!err)
1483                 err = driver_create_file(&xen_pcibk_pci_driver.driver,
1484                                          &driver_attr_slots);
1485         if (!err)
1486                 err = driver_create_file(&xen_pcibk_pci_driver.driver,
1487                                          &driver_attr_quirks);
1488         if (!err)
1489                 err = driver_create_file(&xen_pcibk_pci_driver.driver,
1490                                          &driver_attr_permissive);
1491
1492         if (!err)
1493                 err = driver_create_file(&xen_pcibk_pci_driver.driver,
1494                                          &driver_attr_irq_handlers);
1495         if (!err)
1496                 err = driver_create_file(&xen_pcibk_pci_driver.driver,
1497                                         &driver_attr_irq_handler_state);
1498         if (err)
1499                 pcistub_exit();
1500
1501 out:
1502         return err;
1503
1504 parse_error:
1505         pr_err("Error parsing pci_devs_to_hide at \"%s\"\n",
1506                pci_devs_to_hide + pos);
1507         return -EINVAL;
1508 }
1509
1510 #ifndef MODULE
1511 /*
1512  * fs_initcall happens before device_initcall
1513  * so xen_pcibk *should* get called first (b/c we
1514  * want to suck up any device before other drivers
1515  * get a chance by being the first pci device
1516  * driver to register)
1517  */
1518 fs_initcall(pcistub_init);
1519 #endif
1520
1521 #ifdef CONFIG_PCI_IOV
1522 static struct pcistub_device *find_vfs(const struct pci_dev *pdev)
1523 {
1524         struct pcistub_device *psdev = NULL;
1525         unsigned long flags;
1526         bool found = false;
1527
1528         spin_lock_irqsave(&pcistub_devices_lock, flags);
1529         list_for_each_entry(psdev, &pcistub_devices, dev_list) {
1530                 if (!psdev->pdev && psdev->dev != pdev
1531                     && pci_physfn(psdev->dev) == pdev) {
1532                         found = true;
1533                         break;
1534                 }
1535         }
1536         spin_unlock_irqrestore(&pcistub_devices_lock, flags);
1537         if (found)
1538                 return psdev;
1539         return NULL;
1540 }
1541
1542 static int pci_stub_notifier(struct notifier_block *nb,
1543                              unsigned long action, void *data)
1544 {
1545         struct device *dev = data;
1546         const struct pci_dev *pdev = to_pci_dev(dev);
1547
1548         if (action != BUS_NOTIFY_UNBIND_DRIVER)
1549                 return NOTIFY_DONE;
1550
1551         if (!pdev->is_physfn)
1552                 return NOTIFY_DONE;
1553
1554         for (;;) {
1555                 struct pcistub_device *psdev = find_vfs(pdev);
1556                 if (!psdev)
1557                         break;
1558                 device_release_driver(&psdev->dev->dev);
1559         }
1560         return NOTIFY_DONE;
1561 }
1562
1563 static struct notifier_block pci_stub_nb = {
1564         .notifier_call = pci_stub_notifier,
1565 };
1566 #endif
1567
1568 static int __init xen_pcibk_init(void)
1569 {
1570         int err;
1571
1572         if (!xen_initial_domain())
1573                 return -ENODEV;
1574
1575         err = xen_pcibk_config_init();
1576         if (err)
1577                 return err;
1578
1579 #ifdef MODULE
1580         err = pcistub_init();
1581         if (err < 0)
1582                 return err;
1583 #endif
1584
1585         pcistub_init_devices_late();
1586         err = xen_pcibk_xenbus_register();
1587         if (err)
1588                 pcistub_exit();
1589 #ifdef CONFIG_PCI_IOV
1590         else
1591                 bus_register_notifier(&pci_bus_type, &pci_stub_nb);
1592 #endif
1593
1594         return err;
1595 }
1596
1597 static void __exit xen_pcibk_cleanup(void)
1598 {
1599 #ifdef CONFIG_PCI_IOV
1600         bus_unregister_notifier(&pci_bus_type, &pci_stub_nb);
1601 #endif
1602         xen_pcibk_xenbus_unregister();
1603         pcistub_exit();
1604 }
1605
1606 module_init(xen_pcibk_init);
1607 module_exit(xen_pcibk_cleanup);
1608
1609 MODULE_LICENSE("Dual BSD/GPL");
1610 MODULE_ALIAS("xen-backend:pci");