drivers/xen/xen-pciback/pci_stub.c

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