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