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