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 #define PCISTUB_DRIVER_NAME "pciback"
  29
  30 static char *pci_devs_to_hide;
  31 wait_queue_head_t xen_pcibk_aer_wait_queue;
  32 /*Add sem for sync AER handling and xen_pcibk remove/reconfigue ops,
  33 * We want to avoid in middle of AER ops, xen_pcibk devices is being removed
  34 */
  35 static DECLARE_RWSEM(pcistub_sem);
  36 module_param_named(hide, pci_devs_to_hide, charp, 0444);
  37
  38 struct pcistub_device_id {
  39         struct list_head slot_list;
  40         int domain;
  41         unsigned char bus;
  42         unsigned int devfn;
  43 };
  44 static LIST_HEAD(pcistub_device_ids);
  45 static DEFINE_SPINLOCK(device_ids_lock);
  46
  47 struct pcistub_device {
  48         struct kref kref;
  49         struct list_head dev_list;
  50         spinlock_t lock;
  51
  52         struct pci_dev *dev;
  53         struct xen_pcibk_device *pdev;/* non-NULL if struct pci_dev is in use */
  54 };
  55
  56 /* Access to pcistub_devices & seized_devices lists and the initialize_devices
  57  * flag must be locked with pcistub_devices_lock
  58  */
  59 static DEFINE_SPINLOCK(pcistub_devices_lock);
  60 static LIST_HEAD(pcistub_devices);
  61
  62 /* wait for device_initcall before initializing our devices
  63  * (see pcistub_init_devices_late)
  64  */
  65 static int initialize_devices;
  66 static LIST_HEAD(seized_devices);
  67
  68 static struct pcistub_device *pcistub_device_alloc(struct pci_dev *dev)
  69 {
  70         struct pcistub_device *psdev;
  71
  72         dev_dbg(&dev->dev, "pcistub_device_alloc\n");
  73
  74         psdev = kzalloc(sizeof(*psdev), GFP_ATOMIC);
  75         if (!psdev)
  76                 return NULL;
  77
  78         psdev->dev = pci_dev_get(dev);
  79         if (!psdev->dev) {
  80                 kfree(psdev);
  81                 return NULL;
  82         }
  83
  84         kref_init(&psdev->kref);
  85         spin_lock_init(&psdev->lock);
  86
  87         return psdev;
  88 }
  89
  90 /* Don't call this directly as it's called by pcistub_device_put */
  91 static void pcistub_device_release(struct kref *kref)
  92 {
  93         struct pcistub_device *psdev;
  94         struct pci_dev *dev;
  95         struct xen_pcibk_dev_data *dev_data;
  96
  97         psdev = container_of(kref, struct pcistub_device, kref);
  98         dev = psdev->dev;
  99         dev_data = pci_get_drvdata(dev);
 100
 101         dev_dbg(&dev->dev, "pcistub_device_release\n");
 102
 103         xen_unregister_device_domain_owner(dev);
 104
 105         /* Call the reset function which does not take lock as this
 106          * is called from "unbind" which takes a device_lock mutex.
 107          */
 108         __pci_reset_function_locked(dev);
 109         if (pci_load_and_free_saved_state(dev, &dev_data->pci_saved_state))
 110                 dev_info(&dev->dev, "Could not reload PCI state\n");
 111         else
 112                 pci_restore_state(dev);
 113
 114         if (dev->msix_cap) {
 115                 struct physdev_pci_device ppdev = {
 116                         .seg = pci_domain_nr(dev->bus),
 117                         .bus = dev->bus->number,
 118                         .devfn = dev->devfn
 119                 };
 120                 int err = HYPERVISOR_physdev_op(PHYSDEVOP_release_msix,
 121                                                 &ppdev);
 122
 123                 if (err && err != -ENOSYS)
 124                         dev_warn(&dev->dev, "MSI-X release failed (%d)\n",
 125                                  err);
 126         }
 127
 128         /* Disable the device */
 129         xen_pcibk_reset_device(dev);
 130
 131         kfree(dev_data);
 132         pci_set_drvdata(dev, NULL);
 133
 134         /* Clean-up the device */
 135         xen_pcibk_config_free_dyn_fields(dev);
 136         xen_pcibk_config_free_dev(dev);
 137
 138         pci_clear_dev_assigned(dev);
 139         pci_dev_put(dev);
 140
 141         kfree(psdev);
 142 }
 143
 144 static inline void pcistub_device_get(struct pcistub_device *psdev)
 145 {
 146         kref_get(&psdev->kref);
 147 }
 148
 149 static inline void pcistub_device_put(struct pcistub_device *psdev)
 150 {
 151         kref_put(&psdev->kref, pcistub_device_release);
 152 }
 153
 154 static struct pcistub_device *pcistub_device_find_locked(int domain, int bus,
 155                                                          int slot, int func)
 156 {
 157         struct pcistub_device *psdev;
 158
 159         list_for_each_entry(psdev, &pcistub_devices, dev_list) {
 160                 if (psdev->dev != NULL
 161                     && domain == pci_domain_nr(psdev->dev->bus)
 162                     && bus == psdev->dev->bus->number
 163                     && slot == PCI_SLOT(psdev->dev->devfn)
 164                     && func == PCI_FUNC(psdev->dev->devfn)) {
 165                         return psdev;
 166                 }
 167         }
 168
 169         return NULL;
 170 }
 171
 172 static struct pcistub_device *pcistub_device_find(int domain, int bus,
 173                                                   int slot, int func)
 174 {
 175         struct pcistub_device *psdev;
 176         unsigned long flags;
 177
 178         spin_lock_irqsave(&pcistub_devices_lock, flags);
 179
 180         psdev = pcistub_device_find_locked(domain, bus, slot, func);
 181         if (psdev)
 182                 pcistub_device_get(psdev);
 183
 184         spin_unlock_irqrestore(&pcistub_devices_lock, flags);
 185         return psdev;
 186 }
 187
 188 static struct pci_dev *pcistub_device_get_pci_dev(struct xen_pcibk_device *pdev,
 189                                                   struct pcistub_device *psdev)
 190 {
 191         struct pci_dev *pci_dev = NULL;
 192         unsigned long flags;
 193
 194         pcistub_device_get(psdev);
 195
 196         spin_lock_irqsave(&psdev->lock, flags);
 197         if (!psdev->pdev) {
 198                 psdev->pdev = pdev;
 199                 pci_dev = psdev->dev;
 200         }
 201         spin_unlock_irqrestore(&psdev->lock, flags);
 202
 203         if (!pci_dev)
 204                 pcistub_device_put(psdev);
 205
 206         return pci_dev;
 207 }
 208
 209 struct pci_dev *pcistub_get_pci_dev_by_slot(struct xen_pcibk_device *pdev,
 210                                             int domain, int bus,
 211                                             int slot, int func)
 212 {
 213         struct pcistub_device *psdev;
 214         struct pci_dev *found_dev = NULL;
 215         unsigned long flags;
 216
 217         spin_lock_irqsave(&pcistub_devices_lock, flags);
 218
 219         psdev = pcistub_device_find_locked(domain, bus, slot, func);
 220         if (psdev)
 221                 found_dev = pcistub_device_get_pci_dev(pdev, psdev);
 222
 223         spin_unlock_irqrestore(&pcistub_devices_lock, flags);
 224         return found_dev;
 225 }
 226
 227 struct pci_dev *pcistub_get_pci_dev(struct xen_pcibk_device *pdev,
 228                                     struct pci_dev *dev)
 229 {
 230         struct pcistub_device *psdev;
 231         struct pci_dev *found_dev = NULL;
 232         unsigned long flags;
 233
 234         spin_lock_irqsave(&pcistub_devices_lock, flags);
 235
 236         list_for_each_entry(psdev, &pcistub_devices, dev_list) {
 237                 if (psdev->dev == dev) {
 238                         found_dev = pcistub_device_get_pci_dev(pdev, psdev);
 239                         break;
 240                 }
 241         }
 242
 243         spin_unlock_irqrestore(&pcistub_devices_lock, flags);
 244         return found_dev;
 245 }
 246
 247 /*
 248  * Called when:
 249  *  - XenBus state has been reconfigure (pci unplug). See xen_pcibk_remove_device
 250  *  - XenBus state has been disconnected (guest shutdown). See xen_pcibk_xenbus_remove
 251  *  - 'echo BDF > unbind' on pciback module with no guest attached. See pcistub_remove
 252  *  - 'echo BDF > unbind' with a guest still using it. See pcistub_remove
 253  *
 254  *  As such we have to be careful.
 255  *
 256  *  To make this easier, the caller has to hold the device lock.
 257  */
 258 void pcistub_put_pci_dev(struct pci_dev *dev)
 259 {
 260         struct pcistub_device *psdev, *found_psdev = NULL;
 261         unsigned long flags;
 262         struct xen_pcibk_dev_data *dev_data;
 263         int ret;
 264
 265         spin_lock_irqsave(&pcistub_devices_lock, flags);
 266
 267         list_for_each_entry(psdev, &pcistub_devices, dev_list) {
 268                 if (psdev->dev == dev) {
 269                         found_psdev = psdev;
 270                         break;
 271                 }
 272         }
 273
 274         spin_unlock_irqrestore(&pcistub_devices_lock, flags);
 275         if (WARN_ON(!found_psdev))
 276                 return;
 277
 278         /*hold this lock for avoiding breaking link between
 279         * pcistub and xen_pcibk when AER is in processing
 280         */
 281         down_write(&pcistub_sem);
 282         /* Cleanup our device
 283          * (so it's ready for the next domain)
 284          */
 285         device_lock_assert(&dev->dev);
 286         __pci_reset_function_locked(dev);
 287
 288         dev_data = pci_get_drvdata(dev);
 289         ret = pci_load_saved_state(dev, dev_data->pci_saved_state);
 290         if (!ret) {
 291                 /*
 292                  * The usual sequence is pci_save_state & pci_restore_state
 293                  * but the guest might have messed the configuration space up.
 294                  * Use the initial version (when device was bound to us).
 295                  */
 296                 pci_restore_state(dev);
 297         } else
 298                 dev_info(&dev->dev, "Could not reload PCI state\n");
 299         /* This disables the device. */
 300         xen_pcibk_reset_device(dev);
 301
 302         /* And cleanup up our emulated fields. */
 303         xen_pcibk_config_reset_dev(dev);
 304         xen_pcibk_config_free_dyn_fields(dev);
 305
 306         xen_unregister_device_domain_owner(dev);
 307
 308         spin_lock_irqsave(&found_psdev->lock, flags);
 309         found_psdev->pdev = NULL;
 310         spin_unlock_irqrestore(&found_psdev->lock, flags);
 311
 312         pcistub_device_put(found_psdev);
 313         up_write(&pcistub_sem);
 314 }
 315
 316 static int pcistub_match_one(struct pci_dev *dev,
 317                              struct pcistub_device_id *pdev_id)
 318 {
 319         /* Match the specified device by domain, bus, slot, func and also if
 320          * any of the device's parent bridges match.
 321          */
 322         for (; dev != NULL; dev = dev->bus->self) {
 323                 if (pci_domain_nr(dev->bus) == pdev_id->domain
 324                     && dev->bus->number == pdev_id->bus
 325                     && dev->devfn == pdev_id->devfn)
 326                         return 1;
 327
 328                 /* Sometimes topmost bridge links to itself. */
 329                 if (dev == dev->bus->self)
 330                         break;
 331         }
 332
 333         return 0;
 334 }
 335
 336 static int pcistub_match(struct pci_dev *dev)
 337 {
 338         struct pcistub_device_id *pdev_id;
 339         unsigned long flags;
 340         int found = 0;
 341
 342         spin_lock_irqsave(&device_ids_lock, flags);
 343         list_for_each_entry(pdev_id, &pcistub_device_ids, slot_list) {
 344                 if (pcistub_match_one(dev, pdev_id)) {
 345                         found = 1;
 346                         break;
 347                 }
 348         }
 349         spin_unlock_irqrestore(&device_ids_lock, flags);
 350
 351         return found;
 352 }
 353
 354 static int pcistub_init_device(struct pci_dev *dev)
 355 {
 356         struct xen_pcibk_dev_data *dev_data;
 357         int err = 0;
 358
 359         dev_dbg(&dev->dev, "initializing...\n");
 360
 361         /* The PCI backend is not intended to be a module (or to work with
 362          * removable PCI devices (yet). If it were, xen_pcibk_config_free()
 363          * would need to be called somewhere to free the memory allocated
 364          * here and then to call kfree(pci_get_drvdata(psdev->dev)).
 365          */
 366         dev_data = kzalloc(sizeof(*dev_data) +  strlen(DRV_NAME "[]")
 367                                 + strlen(pci_name(dev)) + 1, GFP_ATOMIC);
 368         if (!dev_data) {
 369                 err = -ENOMEM;
 370                 goto out;
 371         }
 372         pci_set_drvdata(dev, dev_data);
 373
 374         /*
 375          * Setup name for fake IRQ handler. It will only be enabled
 376          * once the device is turned on by the guest.
 377          */
 378         sprintf(dev_data->irq_name, DRV_NAME "[%s]", pci_name(dev));
 379
 380         dev_dbg(&dev->dev, "initializing config\n");
 381
 382         init_waitqueue_head(&xen_pcibk_aer_wait_queue);
 383         err = xen_pcibk_config_init_dev(dev);
 384         if (err)
 385                 goto out;
 386
 387         /* HACK: Force device (& ACPI) to determine what IRQ it's on - we
 388          * must do this here because pcibios_enable_device may specify
 389          * the pci device's true irq (and possibly its other resources)
 390          * if they differ from what's in the configuration space.
 391          * This makes the assumption that the device's resources won't
 392          * change after this point (otherwise this code may break!)
 393          */
 394         dev_dbg(&dev->dev, "enabling device\n");
 395         err = pci_enable_device(dev);
 396         if (err)
 397                 goto config_release;
 398
 399         if (dev->msix_cap) {
 400                 struct physdev_pci_device ppdev = {
 401                         .seg = pci_domain_nr(dev->bus),
 402                         .bus = dev->bus->number,
 403                         .devfn = dev->devfn
 404                 };
 405
 406                 err = HYPERVISOR_physdev_op(PHYSDEVOP_prepare_msix, &ppdev);
 407                 if (err && err != -ENOSYS)
 408                         dev_err(&dev->dev, "MSI-X preparation failed (%d)\n",
 409                                 err);
 410         }
 411
 412         /* We need the device active to save the state. */
 413         dev_dbg(&dev->dev, "save state of device\n");
 414         pci_save_state(dev);
 415         dev_data->pci_saved_state = pci_store_saved_state(dev);
 416         if (!dev_data->pci_saved_state)
 417                 dev_err(&dev->dev, "Could not store PCI conf saved state!\n");
 418         else {
 419                 dev_dbg(&dev->dev, "resetting (FLR, D3, etc) the device\n");
 420                 __pci_reset_function_locked(dev);
 421                 pci_restore_state(dev);
 422         }
 423         /* Now disable the device (this also ensures some private device
 424          * data is setup before we export)
 425          */
 426         dev_dbg(&dev->dev, "reset device\n");
 427         xen_pcibk_reset_device(dev);
 428
 429         pci_set_dev_assigned(dev);
 430         return 0;
 431
 432 config_release:
 433         xen_pcibk_config_free_dev(dev);
 434
 435 out:
 436         pci_set_drvdata(dev, NULL);
 437         kfree(dev_data);
 438         return err;
 439 }
 440
 441 /*
 442  * Because some initialization still happens on
 443  * devices during fs_initcall, we need to defer
 444  * full initialization of our devices until
 445  * device_initcall.
 446  */
 447 static int __init pcistub_init_devices_late(void)
 448 {
 449         struct pcistub_device *psdev;
 450         unsigned long flags;
 451         int err = 0;
 452
 453         spin_lock_irqsave(&pcistub_devices_lock, flags);
 454
 455         while (!list_empty(&seized_devices)) {
 456                 psdev = container_of(seized_devices.next,
 457                                      struct pcistub_device, dev_list);
 458                 list_del(&psdev->dev_list);
 459
 460                 spin_unlock_irqrestore(&pcistub_devices_lock, flags);
 461
 462                 err = pcistub_init_device(psdev->dev);
 463                 if (err) {
 464                         dev_err(&psdev->dev->dev,
 465                                 "error %d initializing device\n", err);
 466                         kfree(psdev);
 467                         psdev = NULL;
 468                 }
 469
 470                 spin_lock_irqsave(&pcistub_devices_lock, flags);
 471
 472                 if (psdev)
 473                         list_add_tail(&psdev->dev_list, &pcistub_devices);
 474         }
 475
 476         initialize_devices = 1;
 477
 478         spin_unlock_irqrestore(&pcistub_devices_lock, flags);
 479
 480         return 0;
 481 }
 482
 483 static void pcistub_device_id_add_list(struct pcistub_device_id *new,
 484                                        int domain, int bus, unsigned int devfn)
 485 {
 486         struct pcistub_device_id *pci_dev_id;
 487         unsigned long flags;
 488         int found = 0;
 489
 490         spin_lock_irqsave(&device_ids_lock, flags);
 491
 492         list_for_each_entry(pci_dev_id, &pcistub_device_ids, slot_list) {
 493                 if (pci_dev_id->domain == domain && pci_dev_id->bus == bus &&
 494                     pci_dev_id->devfn == devfn) {
 495                         found = 1;
 496                         break;
 497                 }
 498         }
 499
 500         if (!found) {
 501                 new->domain = domain;
 502                 new->bus = bus;
 503                 new->devfn = devfn;
 504                 list_add_tail(&new->slot_list, &pcistub_device_ids);
 505         }
 506
 507         spin_unlock_irqrestore(&device_ids_lock, flags);
 508
 509         if (found)
 510                 kfree(new);
 511 }
 512
 513 static int pcistub_seize(struct pci_dev *dev,
 514                          struct pcistub_device_id *pci_dev_id)
 515 {
 516         struct pcistub_device *psdev;
 517         unsigned long flags;
 518         int err = 0;
 519
 520         psdev = pcistub_device_alloc(dev);
 521         if (!psdev) {
 522                 kfree(pci_dev_id);
 523                 return -ENOMEM;
 524         }
 525
 526         spin_lock_irqsave(&pcistub_devices_lock, flags);
 527
 528         if (initialize_devices) {
 529                 spin_unlock_irqrestore(&pcistub_devices_lock, flags);
 530
 531                 /* don't want irqs disabled when calling pcistub_init_device */
 532                 err = pcistub_init_device(psdev->dev);
 533
 534                 spin_lock_irqsave(&pcistub_devices_lock, flags);
 535
 536                 if (!err)
 537                         list_add(&psdev->dev_list, &pcistub_devices);
 538         } else {
 539                 dev_dbg(&dev->dev, "deferring initialization\n");
 540                 list_add(&psdev->dev_list, &seized_devices);
 541         }
 542
 543         spin_unlock_irqrestore(&pcistub_devices_lock, flags);
 544
 545         if (err) {
 546                 kfree(pci_dev_id);
 547                 pcistub_device_put(psdev);
 548         } else if (pci_dev_id)
 549                 pcistub_device_id_add_list(pci_dev_id, pci_domain_nr(dev->bus),
 550                                            dev->bus->number, dev->devfn);
 551
 552         return err;
 553 }
 554
 555 /* Called when 'bind'. This means we must _NOT_ call pci_reset_function or
 556  * other functions that take the sysfs lock. */
 557 static int pcistub_probe(struct pci_dev *dev, const struct pci_device_id *id)
 558 {
 559         int err = 0, match;
 560         struct pcistub_device_id *pci_dev_id = NULL;
 561
 562         dev_dbg(&dev->dev, "probing...\n");
 563
 564         match = pcistub_match(dev);
 565
 566         if ((dev->driver_override &&
 567              !strcmp(dev->driver_override, PCISTUB_DRIVER_NAME)) ||
 568             match) {
 569
 570                 if (dev->hdr_type != PCI_HEADER_TYPE_NORMAL
 571                     && dev->hdr_type != PCI_HEADER_TYPE_BRIDGE) {
 572                         dev_err(&dev->dev, "can't export pci devices that "
 573                                 "don't have a normal (0) or bridge (1) "
 574                                 "header type!\n");
 575                         err = -ENODEV;
 576                         goto out;
 577                 }
 578
 579                 if (!match) {
 580                         pci_dev_id = kmalloc(sizeof(*pci_dev_id), GFP_ATOMIC);
 581                         if (!pci_dev_id) {
 582                                 err = -ENOMEM;
 583                                 goto out;
 584                         }
 585                 }
 586
 587                 dev_info(&dev->dev, "seizing device\n");
 588                 err = pcistub_seize(dev, pci_dev_id);
 589         } else
 590                 /* Didn't find the device */
 591                 err = -ENODEV;
 592
 593 out:
 594         return err;
 595 }
 596
 597 /* Called when 'unbind'. This means we must _NOT_ call pci_reset_function or
 598  * other functions that take the sysfs lock. */
 599 static void pcistub_remove(struct pci_dev *dev)
 600 {
 601         struct pcistub_device *psdev, *found_psdev = NULL;
 602         unsigned long flags;
 603
 604         dev_dbg(&dev->dev, "removing\n");
 605
 606         spin_lock_irqsave(&pcistub_devices_lock, flags);
 607
 608         xen_pcibk_config_quirk_release(dev);
 609
 610         list_for_each_entry(psdev, &pcistub_devices, dev_list) {
 611                 if (psdev->dev == dev) {
 612                         found_psdev = psdev;
 613                         break;
 614                 }
 615         }
 616
 617         spin_unlock_irqrestore(&pcistub_devices_lock, flags);
 618
 619         if (found_psdev) {
 620                 dev_dbg(&dev->dev, "found device to remove %s\n",
 621                         found_psdev->pdev ? "- in-use" : "");
 622
 623                 if (found_psdev->pdev) {
 624                         int domid = xen_find_device_domain_owner(dev);
 625
 626                         pr_warn("****** removing device %s while still in-use by domain %d! ******\n",
 627                                pci_name(found_psdev->dev), domid);
 628                         pr_warn("****** driver domain may still access this device's i/o resources!\n");
 629                         pr_warn("****** shutdown driver domain before binding device\n");
 630                         pr_warn("****** to other drivers or domains\n");
 631
 632                         /* N.B. This ends up calling pcistub_put_pci_dev which ends up
 633                          * doing the FLR. */
 634                         xen_pcibk_release_pci_dev(found_psdev->pdev,
 635                                                 found_psdev->dev,
 636                                                 false /* caller holds the lock. */);
 637                 }
 638
 639                 spin_lock_irqsave(&pcistub_devices_lock, flags);
 640                 list_del(&found_psdev->dev_list);
 641                 spin_unlock_irqrestore(&pcistub_devices_lock, flags);
 642
 643                 /* the final put for releasing from the list */
 644                 pcistub_device_put(found_psdev);
 645         }
 646 }
 647
 648 static const struct pci_device_id pcistub_ids[] = {
 649         {
 650          .vendor = PCI_ANY_ID,
 651          .device = PCI_ANY_ID,
 652          .subvendor = PCI_ANY_ID,
 653          .subdevice = PCI_ANY_ID,
 654          },
 655         {0,},
 656 };
 657
 658 #define PCI_NODENAME_MAX 40
 659 static void kill_domain_by_device(struct pcistub_device *psdev)
 660 {
 661         struct xenbus_transaction xbt;
 662         int err;
 663         char nodename[PCI_NODENAME_MAX];
 664
 665         BUG_ON(!psdev);
 666         snprintf(nodename, PCI_NODENAME_MAX, "/local/domain/0/backend/pci/%d/0",
 667                 psdev->pdev->xdev->otherend_id);
 668
 669 again:
 670         err = xenbus_transaction_start(&xbt);
 671         if (err) {
 672                 dev_err(&psdev->dev->dev,
 673                         "error %d when start xenbus transaction\n", err);
 674                 return;
 675         }
 676         /*PV AER handlers will set this flag*/
 677         xenbus_printf(xbt, nodename, "aerState" , "aerfail");
 678         err = xenbus_transaction_end(xbt, 0);
 679         if (err) {
 680                 if (err == -EAGAIN)
 681                         goto again;
 682                 dev_err(&psdev->dev->dev,
 683                         "error %d when end xenbus transaction\n", err);
 684                 return;
 685         }
 686 }
 687
 688 /* For each aer recovery step error_detected, mmio_enabled, etc, front_end and
 689  * backend need to have cooperation. In xen_pcibk, those steps will do similar
 690  * jobs: send service request and waiting for front_end response.
 691 */
 692 static pci_ers_result_t common_process(struct pcistub_device *psdev,
 693                                        pci_channel_state_t state, int aer_cmd,
 694                                        pci_ers_result_t result)
 695 {
 696         pci_ers_result_t res = result;
 697         struct xen_pcie_aer_op *aer_op;
 698         struct xen_pcibk_device *pdev = psdev->pdev;
 699         struct xen_pci_sharedinfo *sh_info = pdev->sh_info;
 700         int ret;
 701
 702         /*with PV AER drivers*/
 703         aer_op = &(sh_info->aer_op);
 704         aer_op->cmd = aer_cmd ;
 705         /*useful for error_detected callback*/
 706         aer_op->err = state;
 707         /*pcifront_end BDF*/
 708         ret = xen_pcibk_get_pcifront_dev(psdev->dev, psdev->pdev,
 709                 &aer_op->domain, &aer_op->bus, &aer_op->devfn);
 710         if (!ret) {
 711                 dev_err(&psdev->dev->dev,
 712                         DRV_NAME ": failed to get pcifront device\n");
 713                 return PCI_ERS_RESULT_NONE;
 714         }
 715         wmb();
 716
 717         dev_dbg(&psdev->dev->dev,
 718                         DRV_NAME ": aer_op %x dom %x bus %x devfn %x\n",
 719                         aer_cmd, aer_op->domain, aer_op->bus, aer_op->devfn);
 720         /*local flag to mark there's aer request, xen_pcibk callback will use
 721         * this flag to judge whether we need to check pci-front give aer
 722         * service ack signal
 723         */
 724         set_bit(_PCIB_op_pending, (unsigned long *)&pdev->flags);
 725
 726         /*It is possible that a pcifront conf_read_write ops request invokes
 727         * the callback which cause the spurious execution of wake_up.
 728         * Yet it is harmless and better than a spinlock here
 729         */
 730         set_bit(_XEN_PCIB_active,
 731                 (unsigned long *)&sh_info->flags);
 732         wmb();
 733         notify_remote_via_irq(pdev->evtchn_irq);
 734
 735         ret = wait_event_timeout(xen_pcibk_aer_wait_queue,
 736                                  !(test_bit(_XEN_PCIB_active, (unsigned long *)
 737                                  &sh_info->flags)), 300*HZ);
 738
 739         if (!ret) {
 740                 if (test_bit(_XEN_PCIB_active,
 741                         (unsigned long *)&sh_info->flags)) {
 742                         dev_err(&psdev->dev->dev,
 743                                 "pcifront aer process not responding!\n");
 744                         clear_bit(_XEN_PCIB_active,
 745                           (unsigned long *)&sh_info->flags);
 746                         aer_op->err = PCI_ERS_RESULT_NONE;
 747                         return res;
 748                 }
 749         }
 750         clear_bit(_PCIB_op_pending, (unsigned long *)&pdev->flags);
 751
 752         if (test_bit(_XEN_PCIF_active,
 753                 (unsigned long *)&sh_info->flags)) {
 754                 dev_dbg(&psdev->dev->dev,
 755                         "schedule pci_conf service in " DRV_NAME "\n");
 756                 xen_pcibk_test_and_schedule_op(psdev->pdev);
 757         }
 758
 759         res = (pci_ers_result_t)aer_op->err;
 760         return res;
 761 }
 762
 763 /*
 764 * xen_pcibk_slot_reset: it will send the slot_reset request to  pcifront in case
 765 * of the device driver could provide this service, and then wait for pcifront
 766 * ack.
 767 * @dev: pointer to PCI devices
 768 * return value is used by aer_core do_recovery policy
 769 */
 770 static pci_ers_result_t xen_pcibk_slot_reset(struct pci_dev *dev)
 771 {
 772         struct pcistub_device *psdev;
 773         pci_ers_result_t result;
 774
 775         result = PCI_ERS_RESULT_RECOVERED;
 776         dev_dbg(&dev->dev, "xen_pcibk_slot_reset(bus:%x,devfn:%x)\n",
 777                 dev->bus->number, dev->devfn);
 778
 779         down_write(&pcistub_sem);
 780         psdev = pcistub_device_find(pci_domain_nr(dev->bus),
 781                                 dev->bus->number,
 782                                 PCI_SLOT(dev->devfn),
 783                                 PCI_FUNC(dev->devfn));
 784
 785         if (!psdev || !psdev->pdev) {
 786                 dev_err(&dev->dev,
 787                         DRV_NAME " device is not found/assigned\n");
 788                 goto end;
 789         }
 790
 791         if (!psdev->pdev->sh_info) {
 792                 dev_err(&dev->dev, DRV_NAME " device is not connected or owned"
 793                         " by HVM, kill it\n");
 794                 kill_domain_by_device(psdev);
 795                 goto end;
 796         }
 797
 798         if (!test_bit(_XEN_PCIB_AERHANDLER,
 799                 (unsigned long *)&psdev->pdev->sh_info->flags)) {
 800                 dev_err(&dev->dev,
 801                         "guest with no AER driver should have been killed\n");
 802                 goto end;
 803         }
 804         result = common_process(psdev, 1, XEN_PCI_OP_aer_slotreset, result);
 805
 806         if (result == PCI_ERS_RESULT_NONE ||
 807                 result == PCI_ERS_RESULT_DISCONNECT) {
 808                 dev_dbg(&dev->dev,
 809                         "No AER slot_reset service or disconnected!\n");
 810                 kill_domain_by_device(psdev);
 811         }
 812 end:
 813         if (psdev)
 814                 pcistub_device_put(psdev);
 815         up_write(&pcistub_sem);
 816         return result;
 817
 818 }
 819
 820
 821 /*xen_pcibk_mmio_enabled: it will send the mmio_enabled request to  pcifront
 822 * in case of the device driver could provide this service, and then wait
 823 * for pcifront ack
 824 * @dev: pointer to PCI devices
 825 * return value is used by aer_core do_recovery policy
 826 */
 827
 828 static pci_ers_result_t xen_pcibk_mmio_enabled(struct pci_dev *dev)
 829 {
 830         struct pcistub_device *psdev;
 831         pci_ers_result_t result;
 832
 833         result = PCI_ERS_RESULT_RECOVERED;
 834         dev_dbg(&dev->dev, "xen_pcibk_mmio_enabled(bus:%x,devfn:%x)\n",
 835                 dev->bus->number, dev->devfn);
 836
 837         down_write(&pcistub_sem);
 838         psdev = pcistub_device_find(pci_domain_nr(dev->bus),
 839                                 dev->bus->number,
 840                                 PCI_SLOT(dev->devfn),
 841                                 PCI_FUNC(dev->devfn));
 842
 843         if (!psdev || !psdev->pdev) {
 844                 dev_err(&dev->dev,
 845                         DRV_NAME " device is not found/assigned\n");
 846                 goto end;
 847         }
 848
 849         if (!psdev->pdev->sh_info) {
 850                 dev_err(&dev->dev, DRV_NAME " device is not connected or owned"
 851                         " by HVM, kill it\n");
 852                 kill_domain_by_device(psdev);
 853                 goto end;
 854         }
 855
 856         if (!test_bit(_XEN_PCIB_AERHANDLER,
 857                 (unsigned long *)&psdev->pdev->sh_info->flags)) {
 858                 dev_err(&dev->dev,
 859                         "guest with no AER driver should have been killed\n");
 860                 goto end;
 861         }
 862         result = common_process(psdev, 1, XEN_PCI_OP_aer_mmio, result);
 863
 864         if (result == PCI_ERS_RESULT_NONE ||
 865                 result == PCI_ERS_RESULT_DISCONNECT) {
 866                 dev_dbg(&dev->dev,
 867                         "No AER mmio_enabled service or disconnected!\n");
 868                 kill_domain_by_device(psdev);
 869         }
 870 end:
 871         if (psdev)
 872                 pcistub_device_put(psdev);
 873         up_write(&pcistub_sem);
 874         return result;
 875 }
 876
 877 /*xen_pcibk_error_detected: it will send the error_detected request to  pcifront
 878 * in case of the device driver could provide this service, and then wait
 879 * for pcifront ack.
 880 * @dev: pointer to PCI devices
 881 * @error: the current PCI connection state
 882 * return value is used by aer_core do_recovery policy
 883 */
 884
 885 static pci_ers_result_t xen_pcibk_error_detected(struct pci_dev *dev,
 886         pci_channel_state_t error)
 887 {
 888         struct pcistub_device *psdev;
 889         pci_ers_result_t result;
 890
 891         result = PCI_ERS_RESULT_CAN_RECOVER;
 892         dev_dbg(&dev->dev, "xen_pcibk_error_detected(bus:%x,devfn:%x)\n",
 893                 dev->bus->number, dev->devfn);
 894
 895         down_write(&pcistub_sem);
 896         psdev = pcistub_device_find(pci_domain_nr(dev->bus),
 897                                 dev->bus->number,
 898                                 PCI_SLOT(dev->devfn),
 899                                 PCI_FUNC(dev->devfn));
 900
 901         if (!psdev || !psdev->pdev) {
 902                 dev_err(&dev->dev,
 903                         DRV_NAME " device is not found/assigned\n");
 904                 goto end;
 905         }
 906
 907         if (!psdev->pdev->sh_info) {
 908                 dev_err(&dev->dev, DRV_NAME " device is not connected or owned"
 909                         " by HVM, kill it\n");
 910                 kill_domain_by_device(psdev);
 911                 goto end;
 912         }
 913
 914         /*Guest owns the device yet no aer handler regiested, kill guest*/
 915         if (!test_bit(_XEN_PCIB_AERHANDLER,
 916                 (unsigned long *)&psdev->pdev->sh_info->flags)) {
 917                 dev_dbg(&dev->dev, "guest may have no aer driver, kill it\n");
 918                 kill_domain_by_device(psdev);
 919                 goto end;
 920         }
 921         result = common_process(psdev, error, XEN_PCI_OP_aer_detected, result);
 922
 923         if (result == PCI_ERS_RESULT_NONE ||
 924                 result == PCI_ERS_RESULT_DISCONNECT) {
 925                 dev_dbg(&dev->dev,
 926                         "No AER error_detected service or disconnected!\n");
 927                 kill_domain_by_device(psdev);
 928         }
 929 end:
 930         if (psdev)
 931                 pcistub_device_put(psdev);
 932         up_write(&pcistub_sem);
 933         return result;
 934 }
 935
 936 /*xen_pcibk_error_resume: it will send the error_resume request to  pcifront
 937 * in case of the device driver could provide this service, and then wait
 938 * for pcifront ack.
 939 * @dev: pointer to PCI devices
 940 */
 941
 942 static void xen_pcibk_error_resume(struct pci_dev *dev)
 943 {
 944         struct pcistub_device *psdev;
 945
 946         dev_dbg(&dev->dev, "xen_pcibk_error_resume(bus:%x,devfn:%x)\n",
 947                 dev->bus->number, dev->devfn);
 948
 949         down_write(&pcistub_sem);
 950         psdev = pcistub_device_find(pci_domain_nr(dev->bus),
 951                                 dev->bus->number,
 952                                 PCI_SLOT(dev->devfn),
 953                                 PCI_FUNC(dev->devfn));
 954
 955         if (!psdev || !psdev->pdev) {
 956                 dev_err(&dev->dev,
 957                         DRV_NAME " device is not found/assigned\n");
 958                 goto end;
 959         }
 960
 961         if (!psdev->pdev->sh_info) {
 962                 dev_err(&dev->dev, DRV_NAME " device is not connected or owned"
 963                         " by HVM, kill it\n");
 964                 kill_domain_by_device(psdev);
 965                 goto end;
 966         }
 967
 968         if (!test_bit(_XEN_PCIB_AERHANDLER,
 969                 (unsigned long *)&psdev->pdev->sh_info->flags)) {
 970                 dev_err(&dev->dev,
 971                         "guest with no AER driver should have been killed\n");
 972                 kill_domain_by_device(psdev);
 973                 goto end;
 974         }
 975         common_process(psdev, 1, XEN_PCI_OP_aer_resume,
 976                        PCI_ERS_RESULT_RECOVERED);
 977 end:
 978         if (psdev)
 979                 pcistub_device_put(psdev);
 980         up_write(&pcistub_sem);
 981         return;
 982 }
 983
 984 /*add xen_pcibk AER handling*/
 985 static const struct pci_error_handlers xen_pcibk_error_handler = {
 986         .error_detected = xen_pcibk_error_detected,
 987         .mmio_enabled = xen_pcibk_mmio_enabled,
 988         .slot_reset = xen_pcibk_slot_reset,
 989         .resume = xen_pcibk_error_resume,
 990 };
 991
 992 /*
 993  * Note: There is no MODULE_DEVICE_TABLE entry here because this isn't
 994  * for a normal device. I don't want it to be loaded automatically.
 995  */
 996
 997 static struct pci_driver xen_pcibk_pci_driver = {
 998         /* The name should be xen_pciback, but until the tools are updated
 999          * we will keep it as pciback. */
1000         .name = PCISTUB_DRIVER_NAME,
1001         .id_table = pcistub_ids,
1002         .probe = pcistub_probe,
1003         .remove = pcistub_remove,
1004         .err_handler = &xen_pcibk_error_handler,
1005 };
1006
1007 static inline int str_to_slot(const char *buf, int *domain, int *bus,
1008                               int *slot, int *func)
1009 {
1010         int parsed = 0;
1011
1012         switch (sscanf(buf, " %x:%x:%x.%x %n", domain, bus, slot, func,
1013                        &parsed)) {
1014         case 3:
1015                 *func = -1;
1016                 sscanf(buf, " %x:%x:%x.* %n", domain, bus, slot, &parsed);
1017                 break;
1018         case 2:
1019                 *slot = *func = -1;
1020                 sscanf(buf, " %x:%x:*.* %n", domain, bus, &parsed);
1021                 break;
1022         }
1023         if (parsed && !buf[parsed])
1024                 return 0;
1025
1026         /* try again without domain */
1027         *domain = 0;
1028         switch (sscanf(buf, " %x:%x.%x %n", bus, slot, func, &parsed)) {
1029         case 2:
1030                 *func = -1;
1031                 sscanf(buf, " %x:%x.* %n", bus, slot, &parsed);
1032                 break;
1033         case 1:
1034                 *slot = *func = -1;
1035                 sscanf(buf, " %x:*.* %n", bus, &parsed);
1036                 break;
1037         }
1038         if (parsed && !buf[parsed])
1039                 return 0;
1040
1041         return -EINVAL;
1042 }
1043
1044 static inline int str_to_quirk(const char *buf, int *domain, int *bus, int
1045                                *slot, int *func, int *reg, int *size, int *mask)
1046 {
1047         int parsed = 0;
1048
1049         sscanf(buf, " %x:%x:%x.%x-%x:%x:%x %n", domain, bus, slot, func,
1050                reg, size, mask, &parsed);
1051         if (parsed && !buf[parsed])
1052                 return 0;
1053
1054         /* try again without domain */
1055         *domain = 0;
1056         sscanf(buf, " %x:%x.%x-%x:%x:%x %n", bus, slot, func, reg, size,
1057                mask, &parsed);
1058         if (parsed && !buf[parsed])
1059                 return 0;
1060
1061         return -EINVAL;
1062 }
1063
1064 static int pcistub_device_id_add(int domain, int bus, int slot, int func)
1065 {
1066         struct pcistub_device_id *pci_dev_id;
1067         int rc = 0, devfn = PCI_DEVFN(slot, func);
1068
1069         if (slot < 0) {
1070                 for (slot = 0; !rc && slot < 32; ++slot)
1071                         rc = pcistub_device_id_add(domain, bus, slot, func);
1072                 return rc;
1073         }
1074
1075         if (func < 0) {
1076                 for (func = 0; !rc && func < 8; ++func)
1077                         rc = pcistub_device_id_add(domain, bus, slot, func);
1078                 return rc;
1079         }
1080
1081         if ((
1082 #if !defined(MODULE) /* pci_domains_supported is not being exported */ \
1083     || !defined(CONFIG_PCI_DOMAINS)
1084              !pci_domains_supported ? domain :
1085 #endif
1086              domain < 0 || domain > 0xffff)
1087             || bus < 0 || bus > 0xff
1088             || PCI_SLOT(devfn) != slot
1089             || PCI_FUNC(devfn) != func)
1090                 return -EINVAL;
1091
1092         pci_dev_id = kmalloc(sizeof(*pci_dev_id), GFP_KERNEL);
1093         if (!pci_dev_id)
1094                 return -ENOMEM;
1095
1096         pr_debug("wants to seize %04x:%02x:%02x.%d\n",
1097                  domain, bus, slot, func);
1098
1099         pcistub_device_id_add_list(pci_dev_id, domain, bus, devfn);
1100
1101         return 0;
1102 }
1103
1104 static int pcistub_device_id_remove(int domain, int bus, int slot, int func)
1105 {
1106         struct pcistub_device_id *pci_dev_id, *t;
1107         int err = -ENOENT;
1108         unsigned long flags;
1109
1110         spin_lock_irqsave(&device_ids_lock, flags);
1111         list_for_each_entry_safe(pci_dev_id, t, &pcistub_device_ids,
1112                                  slot_list) {
1113                 if (pci_dev_id->domain == domain && pci_dev_id->bus == bus
1114                     && (slot < 0 || PCI_SLOT(pci_dev_id->devfn) == slot)
1115                     && (func < 0 || PCI_FUNC(pci_dev_id->devfn) == func)) {
1116                         /* Don't break; here because it's possible the same
1117                          * slot could be in the list more than once
1118                          */
1119                         list_del(&pci_dev_id->slot_list);
1120                         kfree(pci_dev_id);
1121
1122                         err = 0;
1123
1124                         pr_debug("removed %04x:%02x:%02x.%d from seize list\n",
1125                                  domain, bus, slot, func);
1126                 }
1127         }
1128         spin_unlock_irqrestore(&device_ids_lock, flags);
1129
1130         return err;
1131 }
1132
1133 static int pcistub_reg_add(int domain, int bus, int slot, int func,
1134                            unsigned int reg, unsigned int size,
1135                            unsigned int mask)
1136 {
1137         int err = 0;
1138         struct pcistub_device *psdev;
1139         struct pci_dev *dev;
1140         struct config_field *field;
1141
1142         if (reg > 0xfff || (size < 4 && (mask >> (size * 8))))
1143                 return -EINVAL;
1144
1145         psdev = pcistub_device_find(domain, bus, slot, func);
1146         if (!psdev) {
1147                 err = -ENODEV;
1148                 goto out;
1149         }
1150         dev = psdev->dev;
1151
1152         field = kzalloc(sizeof(*field), GFP_ATOMIC);
1153         if (!field) {
1154                 err = -ENOMEM;
1155                 goto out;
1156         }
1157
1158         field->offset = reg;
1159         field->size = size;
1160         field->mask = mask;
1161         field->init = NULL;
1162         field->reset = NULL;
1163         field->release = NULL;
1164         field->clean = xen_pcibk_config_field_free;
1165
1166         err = xen_pcibk_config_quirks_add_field(dev, field);
1167         if (err)
1168                 kfree(field);
1169 out:
1170         if (psdev)
1171                 pcistub_device_put(psdev);
1172         return err;
1173 }
1174
1175 static ssize_t new_slot_store(struct device_driver *drv, const char *buf,
1176                               size_t count)
1177 {
1178         int domain, bus, slot, func;
1179         int err;
1180
1181         err = str_to_slot(buf, &domain, &bus, &slot, &func);
1182         if (err)
1183                 goto out;
1184
1185         err = pcistub_device_id_add(domain, bus, slot, func);
1186
1187 out:
1188         if (!err)
1189                 err = count;
1190         return err;
1191 }
1192 static DRIVER_ATTR_WO(new_slot);
1193
1194 static ssize_t remove_slot_store(struct device_driver *drv, const char *buf,
1195                                  size_t count)
1196 {
1197         int domain, bus, slot, func;
1198         int err;
1199
1200         err = str_to_slot(buf, &domain, &bus, &slot, &func);
1201         if (err)
1202                 goto out;
1203
1204         err = pcistub_device_id_remove(domain, bus, slot, func);
1205
1206 out:
1207         if (!err)
1208                 err = count;
1209         return err;
1210 }
1211 static DRIVER_ATTR_WO(remove_slot);
1212
1213 static ssize_t slots_show(struct device_driver *drv, char *buf)
1214 {
1215         struct pcistub_device_id *pci_dev_id;
1216         size_t count = 0;
1217         unsigned long flags;
1218
1219         spin_lock_irqsave(&device_ids_lock, flags);
1220         list_for_each_entry(pci_dev_id, &pcistub_device_ids, slot_list) {
1221                 if (count >= PAGE_SIZE)
1222                         break;
1223
1224                 count += scnprintf(buf + count, PAGE_SIZE - count,
1225                                    "%04x:%02x:%02x.%d\n",
1226                                    pci_dev_id->domain, pci_dev_id->bus,
1227                                    PCI_SLOT(pci_dev_id->devfn),
1228                                    PCI_FUNC(pci_dev_id->devfn));
1229         }
1230         spin_unlock_irqrestore(&device_ids_lock, flags);
1231
1232         return count;
1233 }
1234 static DRIVER_ATTR_RO(slots);
1235
1236 static ssize_t irq_handlers_show(struct device_driver *drv, char *buf)
1237 {
1238         struct pcistub_device *psdev;
1239         struct xen_pcibk_dev_data *dev_data;
1240         size_t count = 0;
1241         unsigned long flags;
1242
1243         spin_lock_irqsave(&pcistub_devices_lock, flags);
1244         list_for_each_entry(psdev, &pcistub_devices, dev_list) {
1245                 if (count >= PAGE_SIZE)
1246                         break;
1247                 if (!psdev->dev)
1248                         continue;
1249                 dev_data = pci_get_drvdata(psdev->dev);
1250                 if (!dev_data)
1251                         continue;
1252                 count +=
1253                     scnprintf(buf + count, PAGE_SIZE - count,
1254                               "%s:%s:%sing:%ld\n",
1255                               pci_name(psdev->dev),
1256                               dev_data->isr_on ? "on" : "off",
1257                               dev_data->ack_intr ? "ack" : "not ack",
1258                               dev_data->handled);
1259         }
1260         spin_unlock_irqrestore(&pcistub_devices_lock, flags);
1261         return count;
1262 }
1263 static DRIVER_ATTR_RO(irq_handlers);
1264
1265 static ssize_t irq_handler_state_store(struct device_driver *drv,
1266                                        const char *buf, size_t count)
1267 {
1268         struct pcistub_device *psdev;
1269         struct xen_pcibk_dev_data *dev_data;
1270         int domain, bus, slot, func;
1271         int err;
1272
1273         err = str_to_slot(buf, &domain, &bus, &slot, &func);
1274         if (err)
1275                 return err;
1276
1277         psdev = pcistub_device_find(domain, bus, slot, func);
1278         if (!psdev) {
1279                 err = -ENOENT;
1280                 goto out;
1281         }
1282
1283         dev_data = pci_get_drvdata(psdev->dev);
1284         if (!dev_data) {
1285                 err = -ENOENT;
1286                 goto out;
1287         }
1288
1289         dev_dbg(&psdev->dev->dev, "%s fake irq handler: %d->%d\n",
1290                 dev_data->irq_name, dev_data->isr_on,
1291                 !dev_data->isr_on);
1292
1293         dev_data->isr_on = !(dev_data->isr_on);
1294         if (dev_data->isr_on)
1295                 dev_data->ack_intr = 1;
1296 out:
1297         if (psdev)
1298                 pcistub_device_put(psdev);
1299         if (!err)
1300                 err = count;
1301         return err;
1302 }
1303 static DRIVER_ATTR_WO(irq_handler_state);
1304
1305 static ssize_t quirks_store(struct device_driver *drv, const char *buf,
1306                             size_t count)
1307 {
1308         int domain, bus, slot, func, reg, size, mask;
1309         int err;
1310
1311         err = str_to_quirk(buf, &domain, &bus, &slot, &func, &reg, &size,
1312                            &mask);
1313         if (err)
1314                 goto out;
1315
1316         err = pcistub_reg_add(domain, bus, slot, func, reg, size, mask);
1317
1318 out:
1319         if (!err)
1320                 err = count;
1321         return err;
1322 }
1323
1324 static ssize_t quirks_show(struct device_driver *drv, char *buf)
1325 {
1326         int count = 0;
1327         unsigned long flags;
1328         struct xen_pcibk_config_quirk *quirk;
1329         struct xen_pcibk_dev_data *dev_data;
1330         const struct config_field *field;
1331         const struct config_field_entry *cfg_entry;
1332
1333         spin_lock_irqsave(&device_ids_lock, flags);
1334         list_for_each_entry(quirk, &xen_pcibk_quirks, quirks_list) {
1335                 if (count >= PAGE_SIZE)
1336                         goto out;
1337
1338                 count += scnprintf(buf + count, PAGE_SIZE - count,
1339                                    "%02x:%02x.%01x\n\t%04x:%04x:%04x:%04x\n",
1340                                    quirk->pdev->bus->number,
1341                                    PCI_SLOT(quirk->pdev->devfn),
1342                                    PCI_FUNC(quirk->pdev->devfn),
1343                                    quirk->devid.vendor, quirk->devid.device,
1344                                    quirk->devid.subvendor,
1345                                    quirk->devid.subdevice);
1346
1347                 dev_data = pci_get_drvdata(quirk->pdev);
1348
1349                 list_for_each_entry(cfg_entry, &dev_data->config_fields, list) {
1350                         field = cfg_entry->field;
1351                         if (count >= PAGE_SIZE)
1352                                 goto out;
1353
1354                         count += scnprintf(buf + count, PAGE_SIZE - count,
1355                                            "\t\t%08x:%01x:%08x\n",
1356                                            cfg_entry->base_offset +
1357                                            field->offset, field->size,
1358                                            field->mask);
1359                 }
1360         }
1361
1362 out:
1363         spin_unlock_irqrestore(&device_ids_lock, flags);
1364
1365         return count;
1366 }
1367 static DRIVER_ATTR_RW(quirks);
1368
1369 static ssize_t permissive_store(struct device_driver *drv, const char *buf,
1370                                 size_t count)
1371 {
1372         int domain, bus, slot, func;
1373         int err;
1374         struct pcistub_device *psdev;
1375         struct xen_pcibk_dev_data *dev_data;
1376
1377         err = str_to_slot(buf, &domain, &bus, &slot, &func);
1378         if (err)
1379                 goto out;
1380
1381         psdev = pcistub_device_find(domain, bus, slot, func);
1382         if (!psdev) {
1383                 err = -ENODEV;
1384                 goto out;
1385         }
1386
1387         dev_data = pci_get_drvdata(psdev->dev);
1388         /* the driver data for a device should never be null at this point */
1389         if (!dev_data) {
1390                 err = -ENXIO;
1391                 goto release;
1392         }
1393         if (!dev_data->permissive) {
1394                 dev_data->permissive = 1;
1395                 /* Let user know that what they're doing could be unsafe */
1396                 dev_warn(&psdev->dev->dev, "enabling permissive mode "
1397                          "configuration space accesses!\n");
1398                 dev_warn(&psdev->dev->dev,
1399                          "permissive mode is potentially unsafe!\n");
1400         }
1401 release:
1402         pcistub_device_put(psdev);
1403 out:
1404         if (!err)
1405                 err = count;
1406         return err;
1407 }
1408
1409 static ssize_t permissive_show(struct device_driver *drv, char *buf)
1410 {
1411         struct pcistub_device *psdev;
1412         struct xen_pcibk_dev_data *dev_data;
1413         size_t count = 0;
1414         unsigned long flags;
1415         spin_lock_irqsave(&pcistub_devices_lock, flags);
1416         list_for_each_entry(psdev, &pcistub_devices, dev_list) {
1417                 if (count >= PAGE_SIZE)
1418                         break;
1419                 if (!psdev->dev)
1420                         continue;
1421                 dev_data = pci_get_drvdata(psdev->dev);
1422                 if (!dev_data || !dev_data->permissive)
1423                         continue;
1424                 count +=
1425                     scnprintf(buf + count, PAGE_SIZE - count, "%s\n",
1426                               pci_name(psdev->dev));
1427         }
1428         spin_unlock_irqrestore(&pcistub_devices_lock, flags);
1429         return count;
1430 }
1431 static DRIVER_ATTR_RW(permissive);
1432
1433 static void pcistub_exit(void)
1434 {
1435         driver_remove_file(&xen_pcibk_pci_driver.driver, &driver_attr_new_slot);
1436         driver_remove_file(&xen_pcibk_pci_driver.driver,
1437                            &driver_attr_remove_slot);
1438         driver_remove_file(&xen_pcibk_pci_driver.driver, &driver_attr_slots);
1439         driver_remove_file(&xen_pcibk_pci_driver.driver, &driver_attr_quirks);
1440         driver_remove_file(&xen_pcibk_pci_driver.driver,
1441                            &driver_attr_permissive);
1442         driver_remove_file(&xen_pcibk_pci_driver.driver,
1443                            &driver_attr_irq_handlers);
1444         driver_remove_file(&xen_pcibk_pci_driver.driver,
1445                            &driver_attr_irq_handler_state);
1446         pci_unregister_driver(&xen_pcibk_pci_driver);
1447 }
1448
1449 static int __init pcistub_init(void)
1450 {
1451         int pos = 0;
1452         int err = 0;
1453         int domain, bus, slot, func;
1454         int parsed;
1455
1456         if (pci_devs_to_hide && *pci_devs_to_hide) {
1457                 do {
1458                         parsed = 0;
1459
1460                         err = sscanf(pci_devs_to_hide + pos,
1461                                      " (%x:%x:%x.%x) %n",
1462                                      &domain, &bus, &slot, &func, &parsed);
1463                         switch (err) {
1464                         case 3:
1465                                 func = -1;
1466                                 sscanf(pci_devs_to_hide + pos,
1467                                        " (%x:%x:%x.*) %n",
1468                                        &domain, &bus, &slot, &parsed);
1469                                 break;
1470                         case 2:
1471                                 slot = func = -1;
1472                                 sscanf(pci_devs_to_hide + pos,
1473                                        " (%x:%x:*.*) %n",
1474                                        &domain, &bus, &parsed);
1475                                 break;
1476                         }
1477
1478                         if (!parsed) {
1479                                 domain = 0;
1480                                 err = sscanf(pci_devs_to_hide + pos,
1481                                              " (%x:%x.%x) %n",
1482                                              &bus, &slot, &func, &parsed);
1483                                 switch (err) {
1484                                 case 2:
1485                                         func = -1;
1486                                         sscanf(pci_devs_to_hide + pos,
1487                                                " (%x:%x.*) %n",
1488                                                &bus, &slot, &parsed);
1489                                         break;
1490                                 case 1:
1491                                         slot = func = -1;
1492                                         sscanf(pci_devs_to_hide + pos,
1493                                                " (%x:*.*) %n",
1494                                                &bus, &parsed);
1495                                         break;
1496                                 }
1497                         }
1498
1499                         if (parsed <= 0)
1500                                 goto parse_error;
1501
1502                         err = pcistub_device_id_add(domain, bus, slot, func);
1503                         if (err)
1504                                 goto out;
1505
1506                         pos += parsed;
1507                 } while (pci_devs_to_hide[pos]);
1508         }
1509
1510         /* If we're the first PCI Device Driver to register, we're the
1511          * first one to get offered PCI devices as they become
1512          * available (and thus we can be the first to grab them)
1513          */
1514         err = pci_register_driver(&xen_pcibk_pci_driver);
1515         if (err < 0)
1516                 goto out;
1517
1518         err = driver_create_file(&xen_pcibk_pci_driver.driver,
1519                                  &driver_attr_new_slot);
1520         if (!err)
1521                 err = driver_create_file(&xen_pcibk_pci_driver.driver,
1522                                          &driver_attr_remove_slot);
1523         if (!err)
1524                 err = driver_create_file(&xen_pcibk_pci_driver.driver,
1525                                          &driver_attr_slots);
1526         if (!err)
1527                 err = driver_create_file(&xen_pcibk_pci_driver.driver,
1528                                          &driver_attr_quirks);
1529         if (!err)
1530                 err = driver_create_file(&xen_pcibk_pci_driver.driver,
1531                                          &driver_attr_permissive);
1532
1533         if (!err)
1534                 err = driver_create_file(&xen_pcibk_pci_driver.driver,
1535                                          &driver_attr_irq_handlers);
1536         if (!err)
1537                 err = driver_create_file(&xen_pcibk_pci_driver.driver,
1538                                         &driver_attr_irq_handler_state);
1539         if (err)
1540                 pcistub_exit();
1541
1542 out:
1543         return err;
1544
1545 parse_error:
1546         pr_err("Error parsing pci_devs_to_hide at \"%s\"\n",
1547                pci_devs_to_hide + pos);
1548         return -EINVAL;
1549 }
1550
1551 #ifndef MODULE
1552 /*
1553  * fs_initcall happens before device_initcall
1554  * so xen_pcibk *should* get called first (b/c we
1555  * want to suck up any device before other drivers
1556  * get a chance by being the first pci device
1557  * driver to register)
1558  */
1559 fs_initcall(pcistub_init);
1560 #endif
1561
1562 #ifdef CONFIG_PCI_IOV
1563 static struct pcistub_device *find_vfs(const struct pci_dev *pdev)
1564 {
1565         struct pcistub_device *psdev = NULL;
1566         unsigned long flags;
1567         bool found = false;
1568
1569         spin_lock_irqsave(&pcistub_devices_lock, flags);
1570         list_for_each_entry(psdev, &pcistub_devices, dev_list) {
1571                 if (!psdev->pdev && psdev->dev != pdev
1572                     && pci_physfn(psdev->dev) == pdev) {
1573                         found = true;
1574                         break;
1575                 }
1576         }
1577         spin_unlock_irqrestore(&pcistub_devices_lock, flags);
1578         if (found)
1579                 return psdev;
1580         return NULL;
1581 }
1582
1583 static int pci_stub_notifier(struct notifier_block *nb,
1584                              unsigned long action, void *data)
1585 {
1586         struct device *dev = data;
1587         const struct pci_dev *pdev = to_pci_dev(dev);
1588
1589         if (action != BUS_NOTIFY_UNBIND_DRIVER)
1590                 return NOTIFY_DONE;
1591
1592         if (!pdev->is_physfn)
1593                 return NOTIFY_DONE;
1594
1595         for (;;) {
1596                 struct pcistub_device *psdev = find_vfs(pdev);
1597                 if (!psdev)
1598                         break;
1599                 device_release_driver(&psdev->dev->dev);
1600         }
1601         return NOTIFY_DONE;
1602 }
1603
1604 static struct notifier_block pci_stub_nb = {
1605         .notifier_call = pci_stub_notifier,
1606 };
1607 #endif
1608
1609 static int __init xen_pcibk_init(void)
1610 {
1611         int err;
1612
1613         if (!xen_initial_domain())
1614                 return -ENODEV;
1615
1616         err = xen_pcibk_config_init();
1617         if (err)
1618                 return err;
1619
1620 #ifdef MODULE
1621         err = pcistub_init();
1622         if (err < 0)
1623                 return err;
1624 #endif
1625
1626         pcistub_init_devices_late();
1627         err = xen_pcibk_xenbus_register();
1628         if (err)
1629                 pcistub_exit();
1630 #ifdef CONFIG_PCI_IOV
1631         else
1632                 bus_register_notifier(&pci_bus_type, &pci_stub_nb);
1633 #endif
1634
1635         return err;
1636 }
1637
1638 static void __exit xen_pcibk_cleanup(void)
1639 {
1640 #ifdef CONFIG_PCI_IOV
1641         bus_unregister_notifier(&pci_bus_type, &pci_stub_nb);
1642 #endif
1643         xen_pcibk_xenbus_unregister();
1644         pcistub_exit();
1645 }
1646
1647 module_init(xen_pcibk_init);
1648 module_exit(xen_pcibk_cleanup);
1649
1650 MODULE_LICENSE("Dual BSD/GPL");
1651 MODULE_ALIAS("xen-backend:pci");