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_free_dyn_fields(dev);
 282         xen_pcibk_config_reset_dev(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                         xen_pcibk_release_pci_dev(found_psdev->pdev,
 555                                                 found_psdev->dev);
 556                 }
 557
 558                 spin_lock_irqsave(&pcistub_devices_lock, flags);
 559                 list_del(&found_psdev->dev_list);
 560                 spin_unlock_irqrestore(&pcistub_devices_lock, flags);
 561
 562                 /* the final put for releasing from the list */
 563                 pcistub_device_put(found_psdev);
 564         }
 565 }
 566
 567 static DEFINE_PCI_DEVICE_TABLE(pcistub_ids) = {
 568         {
 569          .vendor = PCI_ANY_ID,
 570          .device = PCI_ANY_ID,
 571          .subvendor = PCI_ANY_ID,
 572          .subdevice = PCI_ANY_ID,
 573          },
 574         {0,},
 575 };
 576
 577 #define PCI_NODENAME_MAX 40
 578 static void kill_domain_by_device(struct pcistub_device *psdev)
 579 {
 580         struct xenbus_transaction xbt;
 581         int err;
 582         char nodename[PCI_NODENAME_MAX];
 583
 584         BUG_ON(!psdev);
 585         snprintf(nodename, PCI_NODENAME_MAX, "/local/domain/0/backend/pci/%d/0",
 586                 psdev->pdev->xdev->otherend_id);
 587
 588 again:
 589         err = xenbus_transaction_start(&xbt);
 590         if (err) {
 591                 dev_err(&psdev->dev->dev,
 592                         "error %d when start xenbus transaction\n", err);
 593                 return;
 594         }
 595         /*PV AER handlers will set this flag*/
 596         xenbus_printf(xbt, nodename, "aerState" , "aerfail");
 597         err = xenbus_transaction_end(xbt, 0);
 598         if (err) {
 599                 if (err == -EAGAIN)
 600                         goto again;
 601                 dev_err(&psdev->dev->dev,
 602                         "error %d when end xenbus transaction\n", err);
 603                 return;
 604         }
 605 }
 606
 607 /* For each aer recovery step error_detected, mmio_enabled, etc, front_end and
 608  * backend need to have cooperation. In xen_pcibk, those steps will do similar
 609  * jobs: send service request and waiting for front_end response.
 610 */
 611 static pci_ers_result_t common_process(struct pcistub_device *psdev,
 612                                        pci_channel_state_t state, int aer_cmd,
 613                                        pci_ers_result_t result)
 614 {
 615         pci_ers_result_t res = result;
 616         struct xen_pcie_aer_op *aer_op;
 617         int ret;
 618
 619         /*with PV AER drivers*/
 620         aer_op = &(psdev->pdev->sh_info->aer_op);
 621         aer_op->cmd = aer_cmd ;
 622         /*useful for error_detected callback*/
 623         aer_op->err = state;
 624         /*pcifront_end BDF*/
 625         ret = xen_pcibk_get_pcifront_dev(psdev->dev, psdev->pdev,
 626                 &aer_op->domain, &aer_op->bus, &aer_op->devfn);
 627         if (!ret) {
 628                 dev_err(&psdev->dev->dev,
 629                         DRV_NAME ": failed to get pcifront device\n");
 630                 return PCI_ERS_RESULT_NONE;
 631         }
 632         wmb();
 633
 634         dev_dbg(&psdev->dev->dev,
 635                         DRV_NAME ": aer_op %x dom %x bus %x devfn %x\n",
 636                         aer_cmd, aer_op->domain, aer_op->bus, aer_op->devfn);
 637         /*local flag to mark there's aer request, xen_pcibk callback will use
 638         * this flag to judge whether we need to check pci-front give aer
 639         * service ack signal
 640         */
 641         set_bit(_PCIB_op_pending, (unsigned long *)&psdev->pdev->flags);
 642
 643         /*It is possible that a pcifront conf_read_write ops request invokes
 644         * the callback which cause the spurious execution of wake_up.
 645         * Yet it is harmless and better than a spinlock here
 646         */
 647         set_bit(_XEN_PCIB_active,
 648                 (unsigned long *)&psdev->pdev->sh_info->flags);
 649         wmb();
 650         notify_remote_via_irq(psdev->pdev->evtchn_irq);
 651
 652         ret = wait_event_timeout(xen_pcibk_aer_wait_queue,
 653                                  !(test_bit(_XEN_PCIB_active, (unsigned long *)
 654                                  &psdev->pdev->sh_info->flags)), 300*HZ);
 655
 656         if (!ret) {
 657                 if (test_bit(_XEN_PCIB_active,
 658                         (unsigned long *)&psdev->pdev->sh_info->flags)) {
 659                         dev_err(&psdev->dev->dev,
 660                                 "pcifront aer process not responding!\n");
 661                         clear_bit(_XEN_PCIB_active,
 662                           (unsigned long *)&psdev->pdev->sh_info->flags);
 663                         aer_op->err = PCI_ERS_RESULT_NONE;
 664                         return res;
 665                 }
 666         }
 667         clear_bit(_PCIB_op_pending, (unsigned long *)&psdev->pdev->flags);
 668
 669         if (test_bit(_XEN_PCIF_active,
 670                 (unsigned long *)&psdev->pdev->sh_info->flags)) {
 671                 dev_dbg(&psdev->dev->dev,
 672                         "schedule pci_conf service in " DRV_NAME "\n");
 673                 xen_pcibk_test_and_schedule_op(psdev->pdev);
 674         }
 675
 676         res = (pci_ers_result_t)aer_op->err;
 677         return res;
 678 }
 679
 680 /*
 681 * xen_pcibk_slot_reset: it will send the slot_reset request to  pcifront in case
 682 * of the device driver could provide this service, and then wait for pcifront
 683 * ack.
 684 * @dev: pointer to PCI devices
 685 * return value is used by aer_core do_recovery policy
 686 */
 687 static pci_ers_result_t xen_pcibk_slot_reset(struct pci_dev *dev)
 688 {
 689         struct pcistub_device *psdev;
 690         pci_ers_result_t result;
 691
 692         result = PCI_ERS_RESULT_RECOVERED;
 693         dev_dbg(&dev->dev, "xen_pcibk_slot_reset(bus:%x,devfn:%x)\n",
 694                 dev->bus->number, dev->devfn);
 695
 696         down_write(&pcistub_sem);
 697         psdev = pcistub_device_find(pci_domain_nr(dev->bus),
 698                                 dev->bus->number,
 699                                 PCI_SLOT(dev->devfn),
 700                                 PCI_FUNC(dev->devfn));
 701
 702         if (!psdev || !psdev->pdev) {
 703                 dev_err(&dev->dev,
 704                         DRV_NAME " device is not found/assigned\n");
 705                 goto end;
 706         }
 707
 708         if (!psdev->pdev->sh_info) {
 709                 dev_err(&dev->dev, DRV_NAME " device is not connected or owned"
 710                         " by HVM, kill it\n");
 711                 kill_domain_by_device(psdev);
 712                 goto end;
 713         }
 714
 715         if (!test_bit(_XEN_PCIB_AERHANDLER,
 716                 (unsigned long *)&psdev->pdev->sh_info->flags)) {
 717                 dev_err(&dev->dev,
 718                         "guest with no AER driver should have been killed\n");
 719                 goto end;
 720         }
 721         result = common_process(psdev, 1, XEN_PCI_OP_aer_slotreset, result);
 722
 723         if (result == PCI_ERS_RESULT_NONE ||
 724                 result == PCI_ERS_RESULT_DISCONNECT) {
 725                 dev_dbg(&dev->dev,
 726                         "No AER slot_reset service or disconnected!\n");
 727                 kill_domain_by_device(psdev);
 728         }
 729 end:
 730         if (psdev)
 731                 pcistub_device_put(psdev);
 732         up_write(&pcistub_sem);
 733         return result;
 734
 735 }
 736
 737
 738 /*xen_pcibk_mmio_enabled: it will send the mmio_enabled request to  pcifront
 739 * in case of the device driver could provide this service, and then wait
 740 * for pcifront ack
 741 * @dev: pointer to PCI devices
 742 * return value is used by aer_core do_recovery policy
 743 */
 744
 745 static pci_ers_result_t xen_pcibk_mmio_enabled(struct pci_dev *dev)
 746 {
 747         struct pcistub_device *psdev;
 748         pci_ers_result_t result;
 749
 750         result = PCI_ERS_RESULT_RECOVERED;
 751         dev_dbg(&dev->dev, "xen_pcibk_mmio_enabled(bus:%x,devfn:%x)\n",
 752                 dev->bus->number, dev->devfn);
 753
 754         down_write(&pcistub_sem);
 755         psdev = pcistub_device_find(pci_domain_nr(dev->bus),
 756                                 dev->bus->number,
 757                                 PCI_SLOT(dev->devfn),
 758                                 PCI_FUNC(dev->devfn));
 759
 760         if (!psdev || !psdev->pdev) {
 761                 dev_err(&dev->dev,
 762                         DRV_NAME " device is not found/assigned\n");
 763                 goto end;
 764         }
 765
 766         if (!psdev->pdev->sh_info) {
 767                 dev_err(&dev->dev, DRV_NAME " device is not connected or owned"
 768                         " by HVM, kill it\n");
 769                 kill_domain_by_device(psdev);
 770                 goto end;
 771         }
 772
 773         if (!test_bit(_XEN_PCIB_AERHANDLER,
 774                 (unsigned long *)&psdev->pdev->sh_info->flags)) {
 775                 dev_err(&dev->dev,
 776                         "guest with no AER driver should have been killed\n");
 777                 goto end;
 778         }
 779         result = common_process(psdev, 1, XEN_PCI_OP_aer_mmio, result);
 780
 781         if (result == PCI_ERS_RESULT_NONE ||
 782                 result == PCI_ERS_RESULT_DISCONNECT) {
 783                 dev_dbg(&dev->dev,
 784                         "No AER mmio_enabled service or disconnected!\n");
 785                 kill_domain_by_device(psdev);
 786         }
 787 end:
 788         if (psdev)
 789                 pcistub_device_put(psdev);
 790         up_write(&pcistub_sem);
 791         return result;
 792 }
 793
 794 /*xen_pcibk_error_detected: it will send the error_detected request to  pcifront
 795 * in case of the device driver could provide this service, and then wait
 796 * for pcifront ack.
 797 * @dev: pointer to PCI devices
 798 * @error: the current PCI connection state
 799 * return value is used by aer_core do_recovery policy
 800 */
 801
 802 static pci_ers_result_t xen_pcibk_error_detected(struct pci_dev *dev,
 803         pci_channel_state_t error)
 804 {
 805         struct pcistub_device *psdev;
 806         pci_ers_result_t result;
 807
 808         result = PCI_ERS_RESULT_CAN_RECOVER;
 809         dev_dbg(&dev->dev, "xen_pcibk_error_detected(bus:%x,devfn:%x)\n",
 810                 dev->bus->number, dev->devfn);
 811
 812         down_write(&pcistub_sem);
 813         psdev = pcistub_device_find(pci_domain_nr(dev->bus),
 814                                 dev->bus->number,
 815                                 PCI_SLOT(dev->devfn),
 816                                 PCI_FUNC(dev->devfn));
 817
 818         if (!psdev || !psdev->pdev) {
 819                 dev_err(&dev->dev,
 820                         DRV_NAME " device is not found/assigned\n");
 821                 goto end;
 822         }
 823
 824         if (!psdev->pdev->sh_info) {
 825                 dev_err(&dev->dev, DRV_NAME " device is not connected or owned"
 826                         " by HVM, kill it\n");
 827                 kill_domain_by_device(psdev);
 828                 goto end;
 829         }
 830
 831         /*Guest owns the device yet no aer handler regiested, kill guest*/
 832         if (!test_bit(_XEN_PCIB_AERHANDLER,
 833                 (unsigned long *)&psdev->pdev->sh_info->flags)) {
 834                 dev_dbg(&dev->dev, "guest may have no aer driver, kill it\n");
 835                 kill_domain_by_device(psdev);
 836                 goto end;
 837         }
 838         result = common_process(psdev, error, XEN_PCI_OP_aer_detected, result);
 839
 840         if (result == PCI_ERS_RESULT_NONE ||
 841                 result == PCI_ERS_RESULT_DISCONNECT) {
 842                 dev_dbg(&dev->dev,
 843                         "No AER error_detected service or disconnected!\n");
 844                 kill_domain_by_device(psdev);
 845         }
 846 end:
 847         if (psdev)
 848                 pcistub_device_put(psdev);
 849         up_write(&pcistub_sem);
 850         return result;
 851 }
 852
 853 /*xen_pcibk_error_resume: it will send the error_resume request to  pcifront
 854 * in case of the device driver could provide this service, and then wait
 855 * for pcifront ack.
 856 * @dev: pointer to PCI devices
 857 */
 858
 859 static void xen_pcibk_error_resume(struct pci_dev *dev)
 860 {
 861         struct pcistub_device *psdev;
 862
 863         dev_dbg(&dev->dev, "xen_pcibk_error_resume(bus:%x,devfn:%x)\n",
 864                 dev->bus->number, dev->devfn);
 865
 866         down_write(&pcistub_sem);
 867         psdev = pcistub_device_find(pci_domain_nr(dev->bus),
 868                                 dev->bus->number,
 869                                 PCI_SLOT(dev->devfn),
 870                                 PCI_FUNC(dev->devfn));
 871
 872         if (!psdev || !psdev->pdev) {
 873                 dev_err(&dev->dev,
 874                         DRV_NAME " device is not found/assigned\n");
 875                 goto end;
 876         }
 877
 878         if (!psdev->pdev->sh_info) {
 879                 dev_err(&dev->dev, DRV_NAME " device is not connected or owned"
 880                         " by HVM, kill it\n");
 881                 kill_domain_by_device(psdev);
 882                 goto end;
 883         }
 884
 885         if (!test_bit(_XEN_PCIB_AERHANDLER,
 886                 (unsigned long *)&psdev->pdev->sh_info->flags)) {
 887                 dev_err(&dev->dev,
 888                         "guest with no AER driver should have been killed\n");
 889                 kill_domain_by_device(psdev);
 890                 goto end;
 891         }
 892         common_process(psdev, 1, XEN_PCI_OP_aer_resume,
 893                        PCI_ERS_RESULT_RECOVERED);
 894 end:
 895         if (psdev)
 896                 pcistub_device_put(psdev);
 897         up_write(&pcistub_sem);
 898         return;
 899 }
 900
 901 /*add xen_pcibk AER handling*/
 902 static const struct pci_error_handlers xen_pcibk_error_handler = {
 903         .error_detected = xen_pcibk_error_detected,
 904         .mmio_enabled = xen_pcibk_mmio_enabled,
 905         .slot_reset = xen_pcibk_slot_reset,
 906         .resume = xen_pcibk_error_resume,
 907 };
 908
 909 /*
 910  * Note: There is no MODULE_DEVICE_TABLE entry here because this isn't
 911  * for a normal device. I don't want it to be loaded automatically.
 912  */
 913
 914 static struct pci_driver xen_pcibk_pci_driver = {
 915         /* The name should be xen_pciback, but until the tools are updated
 916          * we will keep it as pciback. */
 917         .name = "pciback",
 918         .id_table = pcistub_ids,
 919         .probe = pcistub_probe,
 920         .remove = pcistub_remove,
 921         .err_handler = &xen_pcibk_error_handler,
 922 };
 923
 924 static inline int str_to_slot(const char *buf, int *domain, int *bus,
 925                               int *slot, int *func)
 926 {
 927         int parsed = 0;
 928
 929         switch (sscanf(buf, " %x:%x:%x.%x %n", domain, bus, slot, func,
 930                        &parsed)) {
 931         case 3:
 932                 *func = -1;
 933                 sscanf(buf, " %x:%x:%x.* %n", domain, bus, slot, &parsed);
 934                 break;
 935         case 2:
 936                 *slot = *func = -1;
 937                 sscanf(buf, " %x:%x:*.* %n", domain, bus, &parsed);
 938                 break;
 939         }
 940         if (parsed && !buf[parsed])
 941                 return 0;
 942
 943         /* try again without domain */
 944         *domain = 0;
 945         switch (sscanf(buf, " %x:%x.%x %n", bus, slot, func, &parsed)) {
 946         case 2:
 947                 *func = -1;
 948                 sscanf(buf, " %x:%x.* %n", bus, slot, &parsed);
 949                 break;
 950         case 1:
 951                 *slot = *func = -1;
 952                 sscanf(buf, " %x:*.* %n", bus, &parsed);
 953                 break;
 954         }
 955         if (parsed && !buf[parsed])
 956                 return 0;
 957
 958         return -EINVAL;
 959 }
 960
 961 static inline int str_to_quirk(const char *buf, int *domain, int *bus, int
 962                                *slot, int *func, int *reg, int *size, int *mask)
 963 {
 964         int parsed = 0;
 965
 966         sscanf(buf, " %x:%x:%x.%x-%x:%x:%x %n", domain, bus, slot, func,
 967                reg, size, mask, &parsed);
 968         if (parsed && !buf[parsed])
 969                 return 0;
 970
 971         /* try again without domain */
 972         *domain = 0;
 973         sscanf(buf, " %x:%x.%x-%x:%x:%x %n", bus, slot, func, reg, size,
 974                mask, &parsed);
 975         if (parsed && !buf[parsed])
 976                 return 0;
 977
 978         return -EINVAL;
 979 }
 980
 981 static int pcistub_device_id_add(int domain, int bus, int slot, int func)
 982 {
 983         struct pcistub_device_id *pci_dev_id;
 984         unsigned long flags;
 985         int rc = 0, devfn = PCI_DEVFN(slot, func);
 986
 987         if (slot < 0) {
 988                 for (slot = 0; !rc && slot < 32; ++slot)
 989                         rc = pcistub_device_id_add(domain, bus, slot, func);
 990                 return rc;
 991         }
 992
 993         if (func < 0) {
 994                 for (func = 0; !rc && func < 8; ++func)
 995                         rc = pcistub_device_id_add(domain, bus, slot, func);
 996                 return rc;
 997         }
 998
 999         if ((
1000 #if !defined(MODULE) /* pci_domains_supported is not being exported */ \
1001     || !defined(CONFIG_PCI_DOMAINS)
1002              !pci_domains_supported ? domain :
1003 #endif
1004              domain < 0 || domain > 0xffff)
1005             || bus < 0 || bus > 0xff
1006             || PCI_SLOT(devfn) != slot
1007             || PCI_FUNC(devfn) != func)
1008                 return -EINVAL;
1009
1010         pci_dev_id = kmalloc(sizeof(*pci_dev_id), GFP_KERNEL);
1011         if (!pci_dev_id)
1012                 return -ENOMEM;
1013
1014         pci_dev_id->domain = domain;
1015         pci_dev_id->bus = bus;
1016         pci_dev_id->devfn = devfn;
1017
1018         pr_debug("wants to seize %04x:%02x:%02x.%d\n",
1019                  domain, bus, slot, func);
1020
1021         spin_lock_irqsave(&device_ids_lock, flags);
1022         list_add_tail(&pci_dev_id->slot_list, &pcistub_device_ids);
1023         spin_unlock_irqrestore(&device_ids_lock, flags);
1024
1025         return 0;
1026 }
1027
1028 static int pcistub_device_id_remove(int domain, int bus, int slot, int func)
1029 {
1030         struct pcistub_device_id *pci_dev_id, *t;
1031         int err = -ENOENT;
1032         unsigned long flags;
1033
1034         spin_lock_irqsave(&device_ids_lock, flags);
1035         list_for_each_entry_safe(pci_dev_id, t, &pcistub_device_ids,
1036                                  slot_list) {
1037                 if (pci_dev_id->domain == domain && pci_dev_id->bus == bus
1038                     && (slot < 0 || PCI_SLOT(pci_dev_id->devfn) == slot)
1039                     && (func < 0 || PCI_FUNC(pci_dev_id->devfn) == func)) {
1040                         /* Don't break; here because it's possible the same
1041                          * slot could be in the list more than once
1042                          */
1043                         list_del(&pci_dev_id->slot_list);
1044                         kfree(pci_dev_id);
1045
1046                         err = 0;
1047
1048                         pr_debug("removed %04x:%02x:%02x.%d from seize list\n",
1049                                  domain, bus, slot, func);
1050                 }
1051         }
1052         spin_unlock_irqrestore(&device_ids_lock, flags);
1053
1054         return err;
1055 }
1056
1057 static int pcistub_reg_add(int domain, int bus, int slot, int func,
1058                            unsigned int reg, unsigned int size,
1059                            unsigned int mask)
1060 {
1061         int err = 0;
1062         struct pcistub_device *psdev;
1063         struct pci_dev *dev;
1064         struct config_field *field;
1065
1066         if (reg > 0xfff || (size < 4 && (mask >> (size * 8))))
1067                 return -EINVAL;
1068
1069         psdev = pcistub_device_find(domain, bus, slot, func);
1070         if (!psdev) {
1071                 err = -ENODEV;
1072                 goto out;
1073         }
1074         dev = psdev->dev;
1075
1076         field = kzalloc(sizeof(*field), GFP_ATOMIC);
1077         if (!field) {
1078                 err = -ENOMEM;
1079                 goto out;
1080         }
1081
1082         field->offset = reg;
1083         field->size = size;
1084         field->mask = mask;
1085         field->init = NULL;
1086         field->reset = NULL;
1087         field->release = NULL;
1088         field->clean = xen_pcibk_config_field_free;
1089
1090         err = xen_pcibk_config_quirks_add_field(dev, field);
1091         if (err)
1092                 kfree(field);
1093 out:
1094         if (psdev)
1095                 pcistub_device_put(psdev);
1096         return err;
1097 }
1098
1099 static ssize_t pcistub_slot_add(struct device_driver *drv, const char *buf,
1100                                 size_t count)
1101 {
1102         int domain, bus, slot, func;
1103         int err;
1104
1105         err = str_to_slot(buf, &domain, &bus, &slot, &func);
1106         if (err)
1107                 goto out;
1108
1109         err = pcistub_device_id_add(domain, bus, slot, func);
1110
1111 out:
1112         if (!err)
1113                 err = count;
1114         return err;
1115 }
1116 static DRIVER_ATTR(new_slot, S_IWUSR, NULL, pcistub_slot_add);
1117
1118 static ssize_t pcistub_slot_remove(struct device_driver *drv, const char *buf,
1119                                    size_t count)
1120 {
1121         int domain, bus, slot, func;
1122         int err;
1123
1124         err = str_to_slot(buf, &domain, &bus, &slot, &func);
1125         if (err)
1126                 goto out;
1127
1128         err = pcistub_device_id_remove(domain, bus, slot, func);
1129
1130 out:
1131         if (!err)
1132                 err = count;
1133         return err;
1134 }
1135 static DRIVER_ATTR(remove_slot, S_IWUSR, NULL, pcistub_slot_remove);
1136
1137 static ssize_t pcistub_slot_show(struct device_driver *drv, char *buf)
1138 {
1139         struct pcistub_device_id *pci_dev_id;
1140         size_t count = 0;
1141         unsigned long flags;
1142
1143         spin_lock_irqsave(&device_ids_lock, flags);
1144         list_for_each_entry(pci_dev_id, &pcistub_device_ids, slot_list) {
1145                 if (count >= PAGE_SIZE)
1146                         break;
1147
1148                 count += scnprintf(buf + count, PAGE_SIZE - count,
1149                                    "%04x:%02x:%02x.%d\n",
1150                                    pci_dev_id->domain, pci_dev_id->bus,
1151                                    PCI_SLOT(pci_dev_id->devfn),
1152                                    PCI_FUNC(pci_dev_id->devfn));
1153         }
1154         spin_unlock_irqrestore(&device_ids_lock, flags);
1155
1156         return count;
1157 }
1158 static DRIVER_ATTR(slots, S_IRUSR, pcistub_slot_show, NULL);
1159
1160 static ssize_t pcistub_irq_handler_show(struct device_driver *drv, char *buf)
1161 {
1162         struct pcistub_device *psdev;
1163         struct xen_pcibk_dev_data *dev_data;
1164         size_t count = 0;
1165         unsigned long flags;
1166
1167         spin_lock_irqsave(&pcistub_devices_lock, flags);
1168         list_for_each_entry(psdev, &pcistub_devices, dev_list) {
1169                 if (count >= PAGE_SIZE)
1170                         break;
1171                 if (!psdev->dev)
1172                         continue;
1173                 dev_data = pci_get_drvdata(psdev->dev);
1174                 if (!dev_data)
1175                         continue;
1176                 count +=
1177                     scnprintf(buf + count, PAGE_SIZE - count,
1178                               "%s:%s:%sing:%ld\n",
1179                               pci_name(psdev->dev),
1180                               dev_data->isr_on ? "on" : "off",
1181                               dev_data->ack_intr ? "ack" : "not ack",
1182                               dev_data->handled);
1183         }
1184         spin_unlock_irqrestore(&pcistub_devices_lock, flags);
1185         return count;
1186 }
1187 static DRIVER_ATTR(irq_handlers, S_IRUSR, pcistub_irq_handler_show, NULL);
1188
1189 static ssize_t pcistub_irq_handler_switch(struct device_driver *drv,
1190                                           const char *buf,
1191                                           size_t count)
1192 {
1193         struct pcistub_device *psdev;
1194         struct xen_pcibk_dev_data *dev_data;
1195         int domain, bus, slot, func;
1196         int err;
1197
1198         err = str_to_slot(buf, &domain, &bus, &slot, &func);
1199         if (err)
1200                 return err;
1201
1202         psdev = pcistub_device_find(domain, bus, slot, func);
1203         if (!psdev) {
1204                 err = -ENOENT;
1205                 goto out;
1206         }
1207
1208         dev_data = pci_get_drvdata(psdev->dev);
1209         if (!dev_data) {
1210                 err = -ENOENT;
1211                 goto out;
1212         }
1213
1214         dev_dbg(&psdev->dev->dev, "%s fake irq handler: %d->%d\n",
1215                 dev_data->irq_name, dev_data->isr_on,
1216                 !dev_data->isr_on);
1217
1218         dev_data->isr_on = !(dev_data->isr_on);
1219         if (dev_data->isr_on)
1220                 dev_data->ack_intr = 1;
1221 out:
1222         if (psdev)
1223                 pcistub_device_put(psdev);
1224         if (!err)
1225                 err = count;
1226         return err;
1227 }
1228 static DRIVER_ATTR(irq_handler_state, S_IWUSR, NULL,
1229                    pcistub_irq_handler_switch);
1230
1231 static ssize_t pcistub_quirk_add(struct device_driver *drv, const char *buf,
1232                                  size_t count)
1233 {
1234         int domain, bus, slot, func, reg, size, mask;
1235         int err;
1236
1237         err = str_to_quirk(buf, &domain, &bus, &slot, &func, &reg, &size,
1238                            &mask);
1239         if (err)
1240                 goto out;
1241
1242         err = pcistub_reg_add(domain, bus, slot, func, reg, size, mask);
1243
1244 out:
1245         if (!err)
1246                 err = count;
1247         return err;
1248 }
1249
1250 static ssize_t pcistub_quirk_show(struct device_driver *drv, char *buf)
1251 {
1252         int count = 0;
1253         unsigned long flags;
1254         struct xen_pcibk_config_quirk *quirk;
1255         struct xen_pcibk_dev_data *dev_data;
1256         const struct config_field *field;
1257         const struct config_field_entry *cfg_entry;
1258
1259         spin_lock_irqsave(&device_ids_lock, flags);
1260         list_for_each_entry(quirk, &xen_pcibk_quirks, quirks_list) {
1261                 if (count >= PAGE_SIZE)
1262                         goto out;
1263
1264                 count += scnprintf(buf + count, PAGE_SIZE - count,
1265                                    "%02x:%02x.%01x\n\t%04x:%04x:%04x:%04x\n",
1266                                    quirk->pdev->bus->number,
1267                                    PCI_SLOT(quirk->pdev->devfn),
1268                                    PCI_FUNC(quirk->pdev->devfn),
1269                                    quirk->devid.vendor, quirk->devid.device,
1270                                    quirk->devid.subvendor,
1271                                    quirk->devid.subdevice);
1272
1273                 dev_data = pci_get_drvdata(quirk->pdev);
1274
1275                 list_for_each_entry(cfg_entry, &dev_data->config_fields, list) {
1276                         field = cfg_entry->field;
1277                         if (count >= PAGE_SIZE)
1278                                 goto out;
1279
1280                         count += scnprintf(buf + count, PAGE_SIZE - count,
1281                                            "\t\t%08x:%01x:%08x\n",
1282                                            cfg_entry->base_offset +
1283                                            field->offset, field->size,
1284                                            field->mask);
1285                 }
1286         }
1287
1288 out:
1289         spin_unlock_irqrestore(&device_ids_lock, flags);
1290
1291         return count;
1292 }
1293 static DRIVER_ATTR(quirks, S_IRUSR | S_IWUSR, pcistub_quirk_show,
1294                    pcistub_quirk_add);
1295
1296 static ssize_t permissive_add(struct device_driver *drv, const char *buf,
1297                               size_t count)
1298 {
1299         int domain, bus, slot, func;
1300         int err;
1301         struct pcistub_device *psdev;
1302         struct xen_pcibk_dev_data *dev_data;
1303
1304         err = str_to_slot(buf, &domain, &bus, &slot, &func);
1305         if (err)
1306                 goto out;
1307
1308         psdev = pcistub_device_find(domain, bus, slot, func);
1309         if (!psdev) {
1310                 err = -ENODEV;
1311                 goto out;
1312         }
1313
1314         dev_data = pci_get_drvdata(psdev->dev);
1315         /* the driver data for a device should never be null at this point */
1316         if (!dev_data) {
1317                 err = -ENXIO;
1318                 goto release;
1319         }
1320         if (!dev_data->permissive) {
1321                 dev_data->permissive = 1;
1322                 /* Let user know that what they're doing could be unsafe */
1323                 dev_warn(&psdev->dev->dev, "enabling permissive mode "
1324                          "configuration space accesses!\n");
1325                 dev_warn(&psdev->dev->dev,
1326                          "permissive mode is potentially unsafe!\n");
1327         }
1328 release:
1329         pcistub_device_put(psdev);
1330 out:
1331         if (!err)
1332                 err = count;
1333         return err;
1334 }
1335
1336 static ssize_t permissive_show(struct device_driver *drv, char *buf)
1337 {
1338         struct pcistub_device *psdev;
1339         struct xen_pcibk_dev_data *dev_data;
1340         size_t count = 0;
1341         unsigned long flags;
1342         spin_lock_irqsave(&pcistub_devices_lock, flags);
1343         list_for_each_entry(psdev, &pcistub_devices, dev_list) {
1344                 if (count >= PAGE_SIZE)
1345                         break;
1346                 if (!psdev->dev)
1347                         continue;
1348                 dev_data = pci_get_drvdata(psdev->dev);
1349                 if (!dev_data || !dev_data->permissive)
1350                         continue;
1351                 count +=
1352                     scnprintf(buf + count, PAGE_SIZE - count, "%s\n",
1353                               pci_name(psdev->dev));
1354         }
1355         spin_unlock_irqrestore(&pcistub_devices_lock, flags);
1356         return count;
1357 }
1358 static DRIVER_ATTR(permissive, S_IRUSR | S_IWUSR, permissive_show,
1359                    permissive_add);
1360
1361 static void pcistub_exit(void)
1362 {
1363         driver_remove_file(&xen_pcibk_pci_driver.driver, &driver_attr_new_slot);
1364         driver_remove_file(&xen_pcibk_pci_driver.driver,
1365                            &driver_attr_remove_slot);
1366         driver_remove_file(&xen_pcibk_pci_driver.driver, &driver_attr_slots);
1367         driver_remove_file(&xen_pcibk_pci_driver.driver, &driver_attr_quirks);
1368         driver_remove_file(&xen_pcibk_pci_driver.driver,
1369                            &driver_attr_permissive);
1370         driver_remove_file(&xen_pcibk_pci_driver.driver,
1371                            &driver_attr_irq_handlers);
1372         driver_remove_file(&xen_pcibk_pci_driver.driver,
1373                            &driver_attr_irq_handler_state);
1374         pci_unregister_driver(&xen_pcibk_pci_driver);
1375 }
1376
1377 static int __init pcistub_init(void)
1378 {
1379         int pos = 0;
1380         int err = 0;
1381         int domain, bus, slot, func;
1382         int parsed;
1383
1384         if (pci_devs_to_hide && *pci_devs_to_hide) {
1385                 do {
1386                         parsed = 0;
1387
1388                         err = sscanf(pci_devs_to_hide + pos,
1389                                      " (%x:%x:%x.%x) %n",
1390                                      &domain, &bus, &slot, &func, &parsed);
1391                         switch (err) {
1392                         case 3:
1393                                 func = -1;
1394                                 sscanf(pci_devs_to_hide + pos,
1395                                        " (%x:%x:%x.*) %n",
1396                                        &domain, &bus, &slot, &parsed);
1397                                 break;
1398                         case 2:
1399                                 slot = func = -1;
1400                                 sscanf(pci_devs_to_hide + pos,
1401                                        " (%x:%x:*.*) %n",
1402                                        &domain, &bus, &parsed);
1403                                 break;
1404                         }
1405
1406                         if (!parsed) {
1407                                 domain = 0;
1408                                 err = sscanf(pci_devs_to_hide + pos,
1409                                              " (%x:%x.%x) %n",
1410                                              &bus, &slot, &func, &parsed);
1411                                 switch (err) {
1412                                 case 2:
1413                                         func = -1;
1414                                         sscanf(pci_devs_to_hide + pos,
1415                                                " (%x:%x.*) %n",
1416                                                &bus, &slot, &parsed);
1417                                         break;
1418                                 case 1:
1419                                         slot = func = -1;
1420                                         sscanf(pci_devs_to_hide + pos,
1421                                                " (%x:*.*) %n",
1422                                                &bus, &parsed);
1423                                         break;
1424                                 }
1425                         }
1426
1427                         if (parsed <= 0)
1428                                 goto parse_error;
1429
1430                         err = pcistub_device_id_add(domain, bus, slot, func);
1431                         if (err)
1432                                 goto out;
1433
1434                         pos += parsed;
1435                 } while (pci_devs_to_hide[pos]);
1436         }
1437
1438         /* If we're the first PCI Device Driver to register, we're the
1439          * first one to get offered PCI devices as they become
1440          * available (and thus we can be the first to grab them)
1441          */
1442         err = pci_register_driver(&xen_pcibk_pci_driver);
1443         if (err < 0)
1444                 goto out;
1445
1446         err = driver_create_file(&xen_pcibk_pci_driver.driver,
1447                                  &driver_attr_new_slot);
1448         if (!err)
1449                 err = driver_create_file(&xen_pcibk_pci_driver.driver,
1450                                          &driver_attr_remove_slot);
1451         if (!err)
1452                 err = driver_create_file(&xen_pcibk_pci_driver.driver,
1453                                          &driver_attr_slots);
1454         if (!err)
1455                 err = driver_create_file(&xen_pcibk_pci_driver.driver,
1456                                          &driver_attr_quirks);
1457         if (!err)
1458                 err = driver_create_file(&xen_pcibk_pci_driver.driver,
1459                                          &driver_attr_permissive);
1460
1461         if (!err)
1462                 err = driver_create_file(&xen_pcibk_pci_driver.driver,
1463                                          &driver_attr_irq_handlers);
1464         if (!err)
1465                 err = driver_create_file(&xen_pcibk_pci_driver.driver,
1466                                         &driver_attr_irq_handler_state);
1467         if (err)
1468                 pcistub_exit();
1469
1470 out:
1471         return err;
1472
1473 parse_error:
1474         pr_err("Error parsing pci_devs_to_hide at \"%s\"\n",
1475                pci_devs_to_hide + pos);
1476         return -EINVAL;
1477 }
1478
1479 #ifndef MODULE
1480 /*
1481  * fs_initcall happens before device_initcall
1482  * so xen_pcibk *should* get called first (b/c we
1483  * want to suck up any device before other drivers
1484  * get a chance by being the first pci device
1485  * driver to register)
1486  */
1487 fs_initcall(pcistub_init);
1488 #endif
1489
1490 static int __init xen_pcibk_init(void)
1491 {
1492         int err;
1493
1494         if (!xen_initial_domain())
1495                 return -ENODEV;
1496
1497         err = xen_pcibk_config_init();
1498         if (err)
1499                 return err;
1500
1501 #ifdef MODULE
1502         err = pcistub_init();
1503         if (err < 0)
1504                 return err;
1505 #endif
1506
1507         pcistub_init_devices_late();
1508         err = xen_pcibk_xenbus_register();
1509         if (err)
1510                 pcistub_exit();
1511
1512         return err;
1513 }
1514
1515 static void __exit xen_pcibk_cleanup(void)
1516 {
1517         xen_pcibk_xenbus_unregister();
1518         pcistub_exit();
1519 }
1520
1521 module_init(xen_pcibk_init);
1522 module_exit(xen_pcibk_cleanup);
1523
1524 MODULE_LICENSE("Dual BSD/GPL");
1525 MODULE_ALIAS("xen-backend:pci");