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 __devinit 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 __devinit 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 __devinit 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 __devinit 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 __devinit pcistub_probe(struct pci_dev *dev,
 467                                    const struct pci_device_id *id)
 468 {
 469         int err = 0;
 470
 471         dev_dbg(&dev->dev, "probing...\n");
 472
 473         if (pcistub_match(dev)) {
 474
 475                 if (dev->hdr_type != PCI_HEADER_TYPE_NORMAL
 476                     && dev->hdr_type != PCI_HEADER_TYPE_BRIDGE) {
 477                         dev_err(&dev->dev, "can't export pci devices that "
 478                                 "don't have a normal (0) or bridge (1) "
 479                                 "header type!\n");
 480                         err = -ENODEV;
 481                         goto out;
 482                 }
 483
 484                 dev_info(&dev->dev, "seizing device\n");
 485                 err = pcistub_seize(dev);
 486         } else
 487                 /* Didn't find the device */
 488                 err = -ENODEV;
 489
 490 out:
 491         return err;
 492 }
 493
 494 static void pcistub_remove(struct pci_dev *dev)
 495 {
 496         struct pcistub_device *psdev, *found_psdev = NULL;
 497         unsigned long flags;
 498
 499         dev_dbg(&dev->dev, "removing\n");
 500
 501         spin_lock_irqsave(&pcistub_devices_lock, flags);
 502
 503         xen_pcibk_config_quirk_release(dev);
 504
 505         list_for_each_entry(psdev, &pcistub_devices, dev_list) {
 506                 if (psdev->dev == dev) {
 507                         found_psdev = psdev;
 508                         break;
 509                 }
 510         }
 511
 512         spin_unlock_irqrestore(&pcistub_devices_lock, flags);
 513
 514         if (found_psdev) {
 515                 dev_dbg(&dev->dev, "found device to remove - in use? %p\n",
 516                         found_psdev->pdev);
 517
 518                 if (found_psdev->pdev) {
 519                         printk(KERN_WARNING DRV_NAME ": ****** removing device "
 520                                "%s while still in-use! ******\n",
 521                                pci_name(found_psdev->dev));
 522                         printk(KERN_WARNING DRV_NAME ": ****** driver domain may"
 523                                " still access this device's i/o resources!\n");
 524                         printk(KERN_WARNING DRV_NAME ": ****** shutdown driver "
 525                                "domain before binding device\n");
 526                         printk(KERN_WARNING DRV_NAME ": ****** to other drivers "
 527                                "or domains\n");
 528
 529                         xen_pcibk_release_pci_dev(found_psdev->pdev,
 530                                                 found_psdev->dev);
 531                 }
 532
 533                 spin_lock_irqsave(&pcistub_devices_lock, flags);
 534                 list_del(&found_psdev->dev_list);
 535                 spin_unlock_irqrestore(&pcistub_devices_lock, flags);
 536
 537                 /* the final put for releasing from the list */
 538                 pcistub_device_put(found_psdev);
 539         }
 540 }
 541
 542 static DEFINE_PCI_DEVICE_TABLE(pcistub_ids) = {
 543         {
 544          .vendor = PCI_ANY_ID,
 545          .device = PCI_ANY_ID,
 546          .subvendor = PCI_ANY_ID,
 547          .subdevice = PCI_ANY_ID,
 548          },
 549         {0,},
 550 };
 551
 552 #define PCI_NODENAME_MAX 40
 553 static void kill_domain_by_device(struct pcistub_device *psdev)
 554 {
 555         struct xenbus_transaction xbt;
 556         int err;
 557         char nodename[PCI_NODENAME_MAX];
 558
 559         BUG_ON(!psdev);
 560         snprintf(nodename, PCI_NODENAME_MAX, "/local/domain/0/backend/pci/%d/0",
 561                 psdev->pdev->xdev->otherend_id);
 562
 563 again:
 564         err = xenbus_transaction_start(&xbt);
 565         if (err) {
 566                 dev_err(&psdev->dev->dev,
 567                         "error %d when start xenbus transaction\n", err);
 568                 return;
 569         }
 570         /*PV AER handlers will set this flag*/
 571         xenbus_printf(xbt, nodename, "aerState" , "aerfail");
 572         err = xenbus_transaction_end(xbt, 0);
 573         if (err) {
 574                 if (err == -EAGAIN)
 575                         goto again;
 576                 dev_err(&psdev->dev->dev,
 577                         "error %d when end xenbus transaction\n", err);
 578                 return;
 579         }
 580 }
 581
 582 /* For each aer recovery step error_detected, mmio_enabled, etc, front_end and
 583  * backend need to have cooperation. In xen_pcibk, those steps will do similar
 584  * jobs: send service request and waiting for front_end response.
 585 */
 586 static pci_ers_result_t common_process(struct pcistub_device *psdev,
 587                                        pci_channel_state_t state, int aer_cmd,
 588                                        pci_ers_result_t result)
 589 {
 590         pci_ers_result_t res = result;
 591         struct xen_pcie_aer_op *aer_op;
 592         int ret;
 593
 594         /*with PV AER drivers*/
 595         aer_op = &(psdev->pdev->sh_info->aer_op);
 596         aer_op->cmd = aer_cmd ;
 597         /*useful for error_detected callback*/
 598         aer_op->err = state;
 599         /*pcifront_end BDF*/
 600         ret = xen_pcibk_get_pcifront_dev(psdev->dev, psdev->pdev,
 601                 &aer_op->domain, &aer_op->bus, &aer_op->devfn);
 602         if (!ret) {
 603                 dev_err(&psdev->dev->dev,
 604                         DRV_NAME ": failed to get pcifront device\n");
 605                 return PCI_ERS_RESULT_NONE;
 606         }
 607         wmb();
 608
 609         dev_dbg(&psdev->dev->dev,
 610                         DRV_NAME ": aer_op %x dom %x bus %x devfn %x\n",
 611                         aer_cmd, aer_op->domain, aer_op->bus, aer_op->devfn);
 612         /*local flag to mark there's aer request, xen_pcibk callback will use
 613         * this flag to judge whether we need to check pci-front give aer
 614         * service ack signal
 615         */
 616         set_bit(_PCIB_op_pending, (unsigned long *)&psdev->pdev->flags);
 617
 618         /*It is possible that a pcifront conf_read_write ops request invokes
 619         * the callback which cause the spurious execution of wake_up.
 620         * Yet it is harmless and better than a spinlock here
 621         */
 622         set_bit(_XEN_PCIB_active,
 623                 (unsigned long *)&psdev->pdev->sh_info->flags);
 624         wmb();
 625         notify_remote_via_irq(psdev->pdev->evtchn_irq);
 626
 627         ret = wait_event_timeout(xen_pcibk_aer_wait_queue,
 628                                  !(test_bit(_XEN_PCIB_active, (unsigned long *)
 629                                  &psdev->pdev->sh_info->flags)), 300*HZ);
 630
 631         if (!ret) {
 632                 if (test_bit(_XEN_PCIB_active,
 633                         (unsigned long *)&psdev->pdev->sh_info->flags)) {
 634                         dev_err(&psdev->dev->dev,
 635                                 "pcifront aer process not responding!\n");
 636                         clear_bit(_XEN_PCIB_active,
 637                           (unsigned long *)&psdev->pdev->sh_info->flags);
 638                         aer_op->err = PCI_ERS_RESULT_NONE;
 639                         return res;
 640                 }
 641         }
 642         clear_bit(_PCIB_op_pending, (unsigned long *)&psdev->pdev->flags);
 643
 644         if (test_bit(_XEN_PCIF_active,
 645                 (unsigned long *)&psdev->pdev->sh_info->flags)) {
 646                 dev_dbg(&psdev->dev->dev,
 647                         "schedule pci_conf service in " DRV_NAME "\n");
 648                 xen_pcibk_test_and_schedule_op(psdev->pdev);
 649         }
 650
 651         res = (pci_ers_result_t)aer_op->err;
 652         return res;
 653 }
 654
 655 /*
 656 * xen_pcibk_slot_reset: it will send the slot_reset request to  pcifront in case
 657 * of the device driver could provide this service, and then wait for pcifront
 658 * ack.
 659 * @dev: pointer to PCI devices
 660 * return value is used by aer_core do_recovery policy
 661 */
 662 static pci_ers_result_t xen_pcibk_slot_reset(struct pci_dev *dev)
 663 {
 664         struct pcistub_device *psdev;
 665         pci_ers_result_t result;
 666
 667         result = PCI_ERS_RESULT_RECOVERED;
 668         dev_dbg(&dev->dev, "xen_pcibk_slot_reset(bus:%x,devfn:%x)\n",
 669                 dev->bus->number, dev->devfn);
 670
 671         down_write(&pcistub_sem);
 672         psdev = pcistub_device_find(pci_domain_nr(dev->bus),
 673                                 dev->bus->number,
 674                                 PCI_SLOT(dev->devfn),
 675                                 PCI_FUNC(dev->devfn));
 676
 677         if (!psdev || !psdev->pdev) {
 678                 dev_err(&dev->dev,
 679                         DRV_NAME " device is not found/assigned\n");
 680                 goto end;
 681         }
 682
 683         if (!psdev->pdev->sh_info) {
 684                 dev_err(&dev->dev, DRV_NAME " device is not connected or owned"
 685                         " by HVM, kill it\n");
 686                 kill_domain_by_device(psdev);
 687                 goto end;
 688         }
 689
 690         if (!test_bit(_XEN_PCIB_AERHANDLER,
 691                 (unsigned long *)&psdev->pdev->sh_info->flags)) {
 692                 dev_err(&dev->dev,
 693                         "guest with no AER driver should have been killed\n");
 694                 goto end;
 695         }
 696         result = common_process(psdev, 1, XEN_PCI_OP_aer_slotreset, result);
 697
 698         if (result == PCI_ERS_RESULT_NONE ||
 699                 result == PCI_ERS_RESULT_DISCONNECT) {
 700                 dev_dbg(&dev->dev,
 701                         "No AER slot_reset service or disconnected!\n");
 702                 kill_domain_by_device(psdev);
 703         }
 704 end:
 705         if (psdev)
 706                 pcistub_device_put(psdev);
 707         up_write(&pcistub_sem);
 708         return result;
 709
 710 }
 711
 712
 713 /*xen_pcibk_mmio_enabled: it will send the mmio_enabled request to  pcifront
 714 * in case of the device driver could provide this service, and then wait
 715 * for pcifront ack
 716 * @dev: pointer to PCI devices
 717 * return value is used by aer_core do_recovery policy
 718 */
 719
 720 static pci_ers_result_t xen_pcibk_mmio_enabled(struct pci_dev *dev)
 721 {
 722         struct pcistub_device *psdev;
 723         pci_ers_result_t result;
 724
 725         result = PCI_ERS_RESULT_RECOVERED;
 726         dev_dbg(&dev->dev, "xen_pcibk_mmio_enabled(bus:%x,devfn:%x)\n",
 727                 dev->bus->number, dev->devfn);
 728
 729         down_write(&pcistub_sem);
 730         psdev = pcistub_device_find(pci_domain_nr(dev->bus),
 731                                 dev->bus->number,
 732                                 PCI_SLOT(dev->devfn),
 733                                 PCI_FUNC(dev->devfn));
 734
 735         if (!psdev || !psdev->pdev) {
 736                 dev_err(&dev->dev,
 737                         DRV_NAME " device is not found/assigned\n");
 738                 goto end;
 739         }
 740
 741         if (!psdev->pdev->sh_info) {
 742                 dev_err(&dev->dev, DRV_NAME " device is not connected or owned"
 743                         " by HVM, kill it\n");
 744                 kill_domain_by_device(psdev);
 745                 goto end;
 746         }
 747
 748         if (!test_bit(_XEN_PCIB_AERHANDLER,
 749                 (unsigned long *)&psdev->pdev->sh_info->flags)) {
 750                 dev_err(&dev->dev,
 751                         "guest with no AER driver should have been killed\n");
 752                 goto end;
 753         }
 754         result = common_process(psdev, 1, XEN_PCI_OP_aer_mmio, result);
 755
 756         if (result == PCI_ERS_RESULT_NONE ||
 757                 result == PCI_ERS_RESULT_DISCONNECT) {
 758                 dev_dbg(&dev->dev,
 759                         "No AER mmio_enabled service or disconnected!\n");
 760                 kill_domain_by_device(psdev);
 761         }
 762 end:
 763         if (psdev)
 764                 pcistub_device_put(psdev);
 765         up_write(&pcistub_sem);
 766         return result;
 767 }
 768
 769 /*xen_pcibk_error_detected: it will send the error_detected 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 * @error: the current PCI connection state
 774 * return value is used by aer_core do_recovery policy
 775 */
 776
 777 static pci_ers_result_t xen_pcibk_error_detected(struct pci_dev *dev,
 778         pci_channel_state_t error)
 779 {
 780         struct pcistub_device *psdev;
 781         pci_ers_result_t result;
 782
 783         result = PCI_ERS_RESULT_CAN_RECOVER;
 784         dev_dbg(&dev->dev, "xen_pcibk_error_detected(bus:%x,devfn:%x)\n",
 785                 dev->bus->number, dev->devfn);
 786
 787         down_write(&pcistub_sem);
 788         psdev = pcistub_device_find(pci_domain_nr(dev->bus),
 789                                 dev->bus->number,
 790                                 PCI_SLOT(dev->devfn),
 791                                 PCI_FUNC(dev->devfn));
 792
 793         if (!psdev || !psdev->pdev) {
 794                 dev_err(&dev->dev,
 795                         DRV_NAME " device is not found/assigned\n");
 796                 goto end;
 797         }
 798
 799         if (!psdev->pdev->sh_info) {
 800                 dev_err(&dev->dev, DRV_NAME " device is not connected or owned"
 801                         " by HVM, kill it\n");
 802                 kill_domain_by_device(psdev);
 803                 goto end;
 804         }
 805
 806         /*Guest owns the device yet no aer handler regiested, kill guest*/
 807         if (!test_bit(_XEN_PCIB_AERHANDLER,
 808                 (unsigned long *)&psdev->pdev->sh_info->flags)) {
 809                 dev_dbg(&dev->dev, "guest may have no aer driver, kill it\n");
 810                 kill_domain_by_device(psdev);
 811                 goto end;
 812         }
 813         result = common_process(psdev, error, XEN_PCI_OP_aer_detected, result);
 814
 815         if (result == PCI_ERS_RESULT_NONE ||
 816                 result == PCI_ERS_RESULT_DISCONNECT) {
 817                 dev_dbg(&dev->dev,
 818                         "No AER error_detected service or disconnected!\n");
 819                 kill_domain_by_device(psdev);
 820         }
 821 end:
 822         if (psdev)
 823                 pcistub_device_put(psdev);
 824         up_write(&pcistub_sem);
 825         return result;
 826 }
 827
 828 /*xen_pcibk_error_resume: it will send the error_resume request to  pcifront
 829 * in case of the device driver could provide this service, and then wait
 830 * for pcifront ack.
 831 * @dev: pointer to PCI devices
 832 */
 833
 834 static void xen_pcibk_error_resume(struct pci_dev *dev)
 835 {
 836         struct pcistub_device *psdev;
 837
 838         dev_dbg(&dev->dev, "xen_pcibk_error_resume(bus:%x,devfn:%x)\n",
 839                 dev->bus->number, dev->devfn);
 840
 841         down_write(&pcistub_sem);
 842         psdev = pcistub_device_find(pci_domain_nr(dev->bus),
 843                                 dev->bus->number,
 844                                 PCI_SLOT(dev->devfn),
 845                                 PCI_FUNC(dev->devfn));
 846
 847         if (!psdev || !psdev->pdev) {
 848                 dev_err(&dev->dev,
 849                         DRV_NAME " device is not found/assigned\n");
 850                 goto end;
 851         }
 852
 853         if (!psdev->pdev->sh_info) {
 854                 dev_err(&dev->dev, DRV_NAME " device is not connected or owned"
 855                         " by HVM, kill it\n");
 856                 kill_domain_by_device(psdev);
 857                 goto end;
 858         }
 859
 860         if (!test_bit(_XEN_PCIB_AERHANDLER,
 861                 (unsigned long *)&psdev->pdev->sh_info->flags)) {
 862                 dev_err(&dev->dev,
 863                         "guest with no AER driver should have been killed\n");
 864                 kill_domain_by_device(psdev);
 865                 goto end;
 866         }
 867         common_process(psdev, 1, XEN_PCI_OP_aer_resume,
 868                        PCI_ERS_RESULT_RECOVERED);
 869 end:
 870         if (psdev)
 871                 pcistub_device_put(psdev);
 872         up_write(&pcistub_sem);
 873         return;
 874 }
 875
 876 /*add xen_pcibk AER handling*/
 877 static const struct pci_error_handlers xen_pcibk_error_handler = {
 878         .error_detected = xen_pcibk_error_detected,
 879         .mmio_enabled = xen_pcibk_mmio_enabled,
 880         .slot_reset = xen_pcibk_slot_reset,
 881         .resume = xen_pcibk_error_resume,
 882 };
 883
 884 /*
 885  * Note: There is no MODULE_DEVICE_TABLE entry here because this isn't
 886  * for a normal device. I don't want it to be loaded automatically.
 887  */
 888
 889 static struct pci_driver xen_pcibk_pci_driver = {
 890         /* The name should be xen_pciback, but until the tools are updated
 891          * we will keep it as pciback. */
 892         .name = "pciback",
 893         .id_table = pcistub_ids,
 894         .probe = pcistub_probe,
 895         .remove = pcistub_remove,
 896         .err_handler = &xen_pcibk_error_handler,
 897 };
 898
 899 static inline int str_to_slot(const char *buf, int *domain, int *bus,
 900                               int *slot, int *func)
 901 {
 902         int parsed = 0;
 903
 904         switch (sscanf(buf, " %x:%x:%x.%x %n", domain, bus, slot, func,
 905                        &parsed)) {
 906         case 3:
 907                 *func = -1;
 908                 sscanf(buf, " %x:%x:%x.* %n", domain, bus, slot, &parsed);
 909                 break;
 910         case 2:
 911                 *slot = *func = -1;
 912                 sscanf(buf, " %x:%x:*.* %n", domain, bus, &parsed);
 913                 break;
 914         }
 915         if (parsed && !buf[parsed])
 916                 return 0;
 917
 918         /* try again without domain */
 919         *domain = 0;
 920         switch (sscanf(buf, " %x:%x.%x %n", bus, slot, func, &parsed)) {
 921         case 2:
 922                 *func = -1;
 923                 sscanf(buf, " %x:%x.* %n", bus, slot, &parsed);
 924                 break;
 925         case 1:
 926                 *slot = *func = -1;
 927                 sscanf(buf, " %x:*.* %n", bus, &parsed);
 928                 break;
 929         }
 930         if (parsed && !buf[parsed])
 931                 return 0;
 932
 933         return -EINVAL;
 934 }
 935
 936 static inline int str_to_quirk(const char *buf, int *domain, int *bus, int
 937                                *slot, int *func, int *reg, int *size, int *mask)
 938 {
 939         int parsed = 0;
 940
 941         sscanf(buf, " %x:%x:%x.%x-%x:%x:%x %n", domain, bus, slot, func,
 942                reg, size, mask, &parsed);
 943         if (parsed && !buf[parsed])
 944                 return 0;
 945
 946         /* try again without domain */
 947         *domain = 0;
 948         sscanf(buf, " %x:%x.%x-%x:%x:%x %n", bus, slot, func, reg, size,
 949                mask, &parsed);
 950         if (parsed && !buf[parsed])
 951                 return 0;
 952
 953         return -EINVAL;
 954 }
 955
 956 static int pcistub_device_id_add(int domain, int bus, int slot, int func)
 957 {
 958         struct pcistub_device_id *pci_dev_id;
 959         unsigned long flags;
 960         int rc = 0, devfn = PCI_DEVFN(slot, func);
 961
 962         if (slot < 0) {
 963                 for (slot = 0; !rc && slot < 32; ++slot)
 964                         rc = pcistub_device_id_add(domain, bus, slot, func);
 965                 return rc;
 966         }
 967
 968         if (func < 0) {
 969                 for (func = 0; !rc && func < 8; ++func)
 970                         rc = pcistub_device_id_add(domain, bus, slot, func);
 971                 return rc;
 972         }
 973
 974         if ((
 975 #if !defined(MODULE) /* pci_domains_supported is not being exported */ \
 976     || !defined(CONFIG_PCI_DOMAINS)
 977              !pci_domains_supported ? domain :
 978 #endif
 979              domain < 0 || domain > 0xffff)
 980             || bus < 0 || bus > 0xff
 981             || PCI_SLOT(devfn) != slot
 982             || PCI_FUNC(devfn) != func)
 983                 return -EINVAL;
 984
 985         pci_dev_id = kmalloc(sizeof(*pci_dev_id), GFP_KERNEL);
 986         if (!pci_dev_id)
 987                 return -ENOMEM;
 988
 989         pci_dev_id->domain = domain;
 990         pci_dev_id->bus = bus;
 991         pci_dev_id->devfn = devfn;
 992
 993         pr_debug(DRV_NAME ": wants to seize %04x:%02x:%02x.%d\n",
 994                  domain, bus, slot, func);
 995
 996         spin_lock_irqsave(&device_ids_lock, flags);
 997         list_add_tail(&pci_dev_id->slot_list, &pcistub_device_ids);
 998         spin_unlock_irqrestore(&device_ids_lock, flags);
 999
1000         return 0;
1001 }
1002
1003 static int pcistub_device_id_remove(int domain, int bus, int slot, int func)
1004 {
1005         struct pcistub_device_id *pci_dev_id, *t;
1006         int err = -ENOENT;
1007         unsigned long flags;
1008
1009         spin_lock_irqsave(&device_ids_lock, flags);
1010         list_for_each_entry_safe(pci_dev_id, t, &pcistub_device_ids,
1011                                  slot_list) {
1012                 if (pci_dev_id->domain == domain && pci_dev_id->bus == bus
1013                     && (slot < 0 || PCI_SLOT(pci_dev_id->devfn) == slot)
1014                     && (func < 0 || PCI_FUNC(pci_dev_id->devfn) == func)) {
1015                         /* Don't break; here because it's possible the same
1016                          * slot could be in the list more than once
1017                          */
1018                         list_del(&pci_dev_id->slot_list);
1019                         kfree(pci_dev_id);
1020
1021                         err = 0;
1022
1023                         pr_debug(DRV_NAME ": removed %04x:%02x:%02x.%d from "
1024                                  "seize list\n", domain, bus, slot, func);
1025                 }
1026         }
1027         spin_unlock_irqrestore(&device_ids_lock, flags);
1028
1029         return err;
1030 }
1031
1032 static int pcistub_reg_add(int domain, int bus, int slot, int func,
1033                            unsigned int reg, unsigned int size,
1034                            unsigned int mask)
1035 {
1036         int err = 0;
1037         struct pcistub_device *psdev;
1038         struct pci_dev *dev;
1039         struct config_field *field;
1040
1041         if (reg > 0xfff || (size < 4 && (mask >> (size * 8))))
1042                 return -EINVAL;
1043
1044         psdev = pcistub_device_find(domain, bus, slot, func);
1045         if (!psdev) {
1046                 err = -ENODEV;
1047                 goto out;
1048         }
1049         dev = psdev->dev;
1050
1051         field = kzalloc(sizeof(*field), GFP_ATOMIC);
1052         if (!field) {
1053                 err = -ENOMEM;
1054                 goto out;
1055         }
1056
1057         field->offset = reg;
1058         field->size = size;
1059         field->mask = mask;
1060         field->init = NULL;
1061         field->reset = NULL;
1062         field->release = NULL;
1063         field->clean = xen_pcibk_config_field_free;
1064
1065         err = xen_pcibk_config_quirks_add_field(dev, field);
1066         if (err)
1067                 kfree(field);
1068 out:
1069         if (psdev)
1070                 pcistub_device_put(psdev);
1071         return err;
1072 }
1073
1074 static ssize_t pcistub_slot_add(struct device_driver *drv, const char *buf,
1075                                 size_t count)
1076 {
1077         int domain, bus, slot, func;
1078         int err;
1079
1080         err = str_to_slot(buf, &domain, &bus, &slot, &func);
1081         if (err)
1082                 goto out;
1083
1084         err = pcistub_device_id_add(domain, bus, slot, func);
1085
1086 out:
1087         if (!err)
1088                 err = count;
1089         return err;
1090 }
1091 static DRIVER_ATTR(new_slot, S_IWUSR, NULL, pcistub_slot_add);
1092
1093 static ssize_t pcistub_slot_remove(struct device_driver *drv, const char *buf,
1094                                    size_t count)
1095 {
1096         int domain, bus, slot, func;
1097         int err;
1098
1099         err = str_to_slot(buf, &domain, &bus, &slot, &func);
1100         if (err)
1101                 goto out;
1102
1103         err = pcistub_device_id_remove(domain, bus, slot, func);
1104
1105 out:
1106         if (!err)
1107                 err = count;
1108         return err;
1109 }
1110 static DRIVER_ATTR(remove_slot, S_IWUSR, NULL, pcistub_slot_remove);
1111
1112 static ssize_t pcistub_slot_show(struct device_driver *drv, char *buf)
1113 {
1114         struct pcistub_device_id *pci_dev_id;
1115         size_t count = 0;
1116         unsigned long flags;
1117
1118         spin_lock_irqsave(&device_ids_lock, flags);
1119         list_for_each_entry(pci_dev_id, &pcistub_device_ids, slot_list) {
1120                 if (count >= PAGE_SIZE)
1121                         break;
1122
1123                 count += scnprintf(buf + count, PAGE_SIZE - count,
1124                                    "%04x:%02x:%02x.%d\n",
1125                                    pci_dev_id->domain, pci_dev_id->bus,
1126                                    PCI_SLOT(pci_dev_id->devfn),
1127                                    PCI_FUNC(pci_dev_id->devfn));
1128         }
1129         spin_unlock_irqrestore(&device_ids_lock, flags);
1130
1131         return count;
1132 }
1133 static DRIVER_ATTR(slots, S_IRUSR, pcistub_slot_show, NULL);
1134
1135 static ssize_t pcistub_irq_handler_show(struct device_driver *drv, char *buf)
1136 {
1137         struct pcistub_device *psdev;
1138         struct xen_pcibk_dev_data *dev_data;
1139         size_t count = 0;
1140         unsigned long flags;
1141
1142         spin_lock_irqsave(&pcistub_devices_lock, flags);
1143         list_for_each_entry(psdev, &pcistub_devices, dev_list) {
1144                 if (count >= PAGE_SIZE)
1145                         break;
1146                 if (!psdev->dev)
1147                         continue;
1148                 dev_data = pci_get_drvdata(psdev->dev);
1149                 if (!dev_data)
1150                         continue;
1151                 count +=
1152                     scnprintf(buf + count, PAGE_SIZE - count,
1153                               "%s:%s:%sing:%ld\n",
1154                               pci_name(psdev->dev),
1155                               dev_data->isr_on ? "on" : "off",
1156                               dev_data->ack_intr ? "ack" : "not ack",
1157                               dev_data->handled);
1158         }
1159         spin_unlock_irqrestore(&pcistub_devices_lock, flags);
1160         return count;
1161 }
1162 static DRIVER_ATTR(irq_handlers, S_IRUSR, pcistub_irq_handler_show, NULL);
1163
1164 static ssize_t pcistub_irq_handler_switch(struct device_driver *drv,
1165                                           const char *buf,
1166                                           size_t count)
1167 {
1168         struct pcistub_device *psdev;
1169         struct xen_pcibk_dev_data *dev_data;
1170         int domain, bus, slot, func;
1171         int err = -ENOENT;
1172
1173         err = str_to_slot(buf, &domain, &bus, &slot, &func);
1174         if (err)
1175                 return err;
1176
1177         psdev = pcistub_device_find(domain, bus, slot, func);
1178         if (!psdev)
1179                 goto out;
1180
1181         dev_data = pci_get_drvdata(psdev->dev);
1182         if (!dev_data)
1183                 goto out;
1184
1185         dev_dbg(&psdev->dev->dev, "%s fake irq handler: %d->%d\n",
1186                 dev_data->irq_name, dev_data->isr_on,
1187                 !dev_data->isr_on);
1188
1189         dev_data->isr_on = !(dev_data->isr_on);
1190         if (dev_data->isr_on)
1191                 dev_data->ack_intr = 1;
1192 out:
1193         if (psdev)
1194                 pcistub_device_put(psdev);
1195         if (!err)
1196                 err = count;
1197         return err;
1198 }
1199 static DRIVER_ATTR(irq_handler_state, S_IWUSR, NULL,
1200                    pcistub_irq_handler_switch);
1201
1202 static ssize_t pcistub_quirk_add(struct device_driver *drv, const char *buf,
1203                                  size_t count)
1204 {
1205         int domain, bus, slot, func, reg, size, mask;
1206         int err;
1207
1208         err = str_to_quirk(buf, &domain, &bus, &slot, &func, &reg, &size,
1209                            &mask);
1210         if (err)
1211                 goto out;
1212
1213         err = pcistub_reg_add(domain, bus, slot, func, reg, size, mask);
1214
1215 out:
1216         if (!err)
1217                 err = count;
1218         return err;
1219 }
1220
1221 static ssize_t pcistub_quirk_show(struct device_driver *drv, char *buf)
1222 {
1223         int count = 0;
1224         unsigned long flags;
1225         struct xen_pcibk_config_quirk *quirk;
1226         struct xen_pcibk_dev_data *dev_data;
1227         const struct config_field *field;
1228         const struct config_field_entry *cfg_entry;
1229
1230         spin_lock_irqsave(&device_ids_lock, flags);
1231         list_for_each_entry(quirk, &xen_pcibk_quirks, quirks_list) {
1232                 if (count >= PAGE_SIZE)
1233                         goto out;
1234
1235                 count += scnprintf(buf + count, PAGE_SIZE - count,
1236                                    "%02x:%02x.%01x\n\t%04x:%04x:%04x:%04x\n",
1237                                    quirk->pdev->bus->number,
1238                                    PCI_SLOT(quirk->pdev->devfn),
1239                                    PCI_FUNC(quirk->pdev->devfn),
1240                                    quirk->devid.vendor, quirk->devid.device,
1241                                    quirk->devid.subvendor,
1242                                    quirk->devid.subdevice);
1243
1244                 dev_data = pci_get_drvdata(quirk->pdev);
1245
1246                 list_for_each_entry(cfg_entry, &dev_data->config_fields, list) {
1247                         field = cfg_entry->field;
1248                         if (count >= PAGE_SIZE)
1249                                 goto out;
1250
1251                         count += scnprintf(buf + count, PAGE_SIZE - count,
1252                                            "\t\t%08x:%01x:%08x\n",
1253                                            cfg_entry->base_offset +
1254                                            field->offset, field->size,
1255                                            field->mask);
1256                 }
1257         }
1258
1259 out:
1260         spin_unlock_irqrestore(&device_ids_lock, flags);
1261
1262         return count;
1263 }
1264 static DRIVER_ATTR(quirks, S_IRUSR | S_IWUSR, pcistub_quirk_show,
1265                    pcistub_quirk_add);
1266
1267 static ssize_t permissive_add(struct device_driver *drv, const char *buf,
1268                               size_t count)
1269 {
1270         int domain, bus, slot, func;
1271         int err;
1272         struct pcistub_device *psdev;
1273         struct xen_pcibk_dev_data *dev_data;
1274
1275         err = str_to_slot(buf, &domain, &bus, &slot, &func);
1276         if (err)
1277                 goto out;
1278
1279         psdev = pcistub_device_find(domain, bus, slot, func);
1280         if (!psdev) {
1281                 err = -ENODEV;
1282                 goto out;
1283         }
1284
1285         dev_data = pci_get_drvdata(psdev->dev);
1286         /* the driver data for a device should never be null at this point */
1287         if (!dev_data) {
1288                 err = -ENXIO;
1289                 goto release;
1290         }
1291         if (!dev_data->permissive) {
1292                 dev_data->permissive = 1;
1293                 /* Let user know that what they're doing could be unsafe */
1294                 dev_warn(&psdev->dev->dev, "enabling permissive mode "
1295                          "configuration space accesses!\n");
1296                 dev_warn(&psdev->dev->dev,
1297                          "permissive mode is potentially unsafe!\n");
1298         }
1299 release:
1300         pcistub_device_put(psdev);
1301 out:
1302         if (!err)
1303                 err = count;
1304         return err;
1305 }
1306
1307 static ssize_t permissive_show(struct device_driver *drv, char *buf)
1308 {
1309         struct pcistub_device *psdev;
1310         struct xen_pcibk_dev_data *dev_data;
1311         size_t count = 0;
1312         unsigned long flags;
1313         spin_lock_irqsave(&pcistub_devices_lock, flags);
1314         list_for_each_entry(psdev, &pcistub_devices, dev_list) {
1315                 if (count >= PAGE_SIZE)
1316                         break;
1317                 if (!psdev->dev)
1318                         continue;
1319                 dev_data = pci_get_drvdata(psdev->dev);
1320                 if (!dev_data || !dev_data->permissive)
1321                         continue;
1322                 count +=
1323                     scnprintf(buf + count, PAGE_SIZE - count, "%s\n",
1324                               pci_name(psdev->dev));
1325         }
1326         spin_unlock_irqrestore(&pcistub_devices_lock, flags);
1327         return count;
1328 }
1329 static DRIVER_ATTR(permissive, S_IRUSR | S_IWUSR, permissive_show,
1330                    permissive_add);
1331
1332 static void pcistub_exit(void)
1333 {
1334         driver_remove_file(&xen_pcibk_pci_driver.driver, &driver_attr_new_slot);
1335         driver_remove_file(&xen_pcibk_pci_driver.driver,
1336                            &driver_attr_remove_slot);
1337         driver_remove_file(&xen_pcibk_pci_driver.driver, &driver_attr_slots);
1338         driver_remove_file(&xen_pcibk_pci_driver.driver, &driver_attr_quirks);
1339         driver_remove_file(&xen_pcibk_pci_driver.driver,
1340                            &driver_attr_permissive);
1341         driver_remove_file(&xen_pcibk_pci_driver.driver,
1342                            &driver_attr_irq_handlers);
1343         driver_remove_file(&xen_pcibk_pci_driver.driver,
1344                            &driver_attr_irq_handler_state);
1345         pci_unregister_driver(&xen_pcibk_pci_driver);
1346 }
1347
1348 static int __init pcistub_init(void)
1349 {
1350         int pos = 0;
1351         int err = 0;
1352         int domain, bus, slot, func;
1353         int parsed;
1354
1355         if (pci_devs_to_hide && *pci_devs_to_hide) {
1356                 do {
1357                         parsed = 0;
1358
1359                         err = sscanf(pci_devs_to_hide + pos,
1360                                      " (%x:%x:%x.%x) %n",
1361                                      &domain, &bus, &slot, &func, &parsed);
1362                         switch (err) {
1363                         case 3:
1364                                 func = -1;
1365                                 sscanf(pci_devs_to_hide + pos,
1366                                        " (%x:%x:%x.*) %n",
1367                                        &domain, &bus, &slot, &parsed);
1368                                 break;
1369                         case 2:
1370                                 slot = func = -1;
1371                                 sscanf(pci_devs_to_hide + pos,
1372                                        " (%x:%x:*.*) %n",
1373                                        &domain, &bus, &parsed);
1374                                 break;
1375                         }
1376
1377                         if (!parsed) {
1378                                 domain = 0;
1379                                 err = sscanf(pci_devs_to_hide + pos,
1380                                              " (%x:%x.%x) %n",
1381                                              &bus, &slot, &func, &parsed);
1382                                 switch (err) {
1383                                 case 2:
1384                                         func = -1;
1385                                         sscanf(pci_devs_to_hide + pos,
1386                                                " (%x:%x.*) %n",
1387                                                &bus, &slot, &parsed);
1388                                         break;
1389                                 case 1:
1390                                         slot = func = -1;
1391                                         sscanf(pci_devs_to_hide + pos,
1392                                                " (%x:*.*) %n",
1393                                                &bus, &parsed);
1394                                         break;
1395                                 }
1396                         }
1397
1398                         if (parsed <= 0)
1399                                 goto parse_error;
1400
1401                         err = pcistub_device_id_add(domain, bus, slot, func);
1402                         if (err)
1403                                 goto out;
1404
1405                         pos += parsed;
1406                 } while (pci_devs_to_hide[pos]);
1407         }
1408
1409         /* If we're the first PCI Device Driver to register, we're the
1410          * first one to get offered PCI devices as they become
1411          * available (and thus we can be the first to grab them)
1412          */
1413         err = pci_register_driver(&xen_pcibk_pci_driver);
1414         if (err < 0)
1415                 goto out;
1416
1417         err = driver_create_file(&xen_pcibk_pci_driver.driver,
1418                                  &driver_attr_new_slot);
1419         if (!err)
1420                 err = driver_create_file(&xen_pcibk_pci_driver.driver,
1421                                          &driver_attr_remove_slot);
1422         if (!err)
1423                 err = driver_create_file(&xen_pcibk_pci_driver.driver,
1424                                          &driver_attr_slots);
1425         if (!err)
1426                 err = driver_create_file(&xen_pcibk_pci_driver.driver,
1427                                          &driver_attr_quirks);
1428         if (!err)
1429                 err = driver_create_file(&xen_pcibk_pci_driver.driver,
1430                                          &driver_attr_permissive);
1431
1432         if (!err)
1433                 err = driver_create_file(&xen_pcibk_pci_driver.driver,
1434                                          &driver_attr_irq_handlers);
1435         if (!err)
1436                 err = driver_create_file(&xen_pcibk_pci_driver.driver,
1437                                         &driver_attr_irq_handler_state);
1438         if (err)
1439                 pcistub_exit();
1440
1441 out:
1442         return err;
1443
1444 parse_error:
1445         printk(KERN_ERR DRV_NAME ": Error parsing pci_devs_to_hide at \"%s\"\n",
1446                pci_devs_to_hide + pos);
1447         return -EINVAL;
1448 }
1449
1450 #ifndef MODULE
1451 /*
1452  * fs_initcall happens before device_initcall
1453  * so xen_pcibk *should* get called first (b/c we
1454  * want to suck up any device before other drivers
1455  * get a chance by being the first pci device
1456  * driver to register)
1457  */
1458 fs_initcall(pcistub_init);
1459 #endif
1460
1461 static int __init xen_pcibk_init(void)
1462 {
1463         int err;
1464
1465         if (!xen_initial_domain())
1466                 return -ENODEV;
1467
1468         err = xen_pcibk_config_init();
1469         if (err)
1470                 return err;
1471
1472 #ifdef MODULE
1473         err = pcistub_init();
1474         if (err < 0)
1475                 return err;
1476 #endif
1477
1478         pcistub_init_devices_late();
1479         err = xen_pcibk_xenbus_register();
1480         if (err)
1481                 pcistub_exit();
1482
1483         return err;
1484 }
1485
1486 static void __exit xen_pcibk_cleanup(void)
1487 {
1488         xen_pcibk_xenbus_unregister();
1489         pcistub_exit();
1490 }
1491
1492 module_init(xen_pcibk_init);
1493 module_exit(xen_pcibk_cleanup);
1494
1495 MODULE_LICENSE("Dual BSD/GPL");
1496 MODULE_ALIAS("xen-backend:pci");