drivers/xen/xen-pciback/pci_stub.c

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