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_KERNEL);
  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 (dev_data &&
 110             pci_load_and_free_saved_state(dev, &dev_data->pci_saved_state))
 111                 dev_info(&dev->dev, "Could not reload PCI state\n");
 112         else
 113                 pci_restore_state(dev);
 114
 115         if (dev->msix_cap) {
 116                 struct physdev_pci_device ppdev = {
 117                         .seg = pci_domain_nr(dev->bus),
 118                         .bus = dev->bus->number,
 119                         .devfn = dev->devfn
 120                 };
 121                 int err = HYPERVISOR_physdev_op(PHYSDEVOP_release_msix,
 122                                                 &ppdev);
 123
 124                 if (err && err != -ENOSYS)
 125                         dev_warn(&dev->dev, "MSI-X release failed (%d)\n",
 126                                  err);
 127         }
 128
 129         /* Disable the device */
 130         xen_pcibk_reset_device(dev);
 131
 132         kfree(dev_data);
 133         pci_set_drvdata(dev, NULL);
 134
 135         /* Clean-up the device */
 136         xen_pcibk_config_free_dyn_fields(dev);
 137         xen_pcibk_config_free_dev(dev);
 138
 139         pci_clear_dev_assigned(dev);
 140         pci_dev_put(dev);
 141
 142         kfree(psdev);
 143 }
 144
 145 static inline void pcistub_device_get(struct pcistub_device *psdev)
 146 {
 147         kref_get(&psdev->kref);
 148 }
 149
 150 static inline void pcistub_device_put(struct pcistub_device *psdev)
 151 {
 152         kref_put(&psdev->kref, pcistub_device_release);
 153 }
 154
 155 static struct pcistub_device *pcistub_device_find_locked(int domain, int bus,
 156                                                          int slot, int func)
 157 {
 158         struct pcistub_device *psdev;
 159
 160         list_for_each_entry(psdev, &pcistub_devices, dev_list) {
 161                 if (psdev->dev != NULL
 162                     && domain == pci_domain_nr(psdev->dev->bus)
 163                     && bus == psdev->dev->bus->number
 164                     && slot == PCI_SLOT(psdev->dev->devfn)
 165                     && func == PCI_FUNC(psdev->dev->devfn)) {
 166                         return psdev;
 167                 }
 168         }
 169
 170         return NULL;
 171 }
 172
 173 static struct pcistub_device *pcistub_device_find(int domain, int bus,
 174                                                   int slot, int func)
 175 {
 176         struct pcistub_device *psdev;
 177         unsigned long flags;
 178
 179         spin_lock_irqsave(&pcistub_devices_lock, flags);
 180
 181         psdev = pcistub_device_find_locked(domain, bus, slot, func);
 182         if (psdev)
 183                 pcistub_device_get(psdev);
 184
 185         spin_unlock_irqrestore(&pcistub_devices_lock, flags);
 186         return psdev;
 187 }
 188
 189 static struct pci_dev *pcistub_device_get_pci_dev(struct xen_pcibk_device *pdev,
 190                                                   struct pcistub_device *psdev)
 191 {
 192         struct pci_dev *pci_dev = NULL;
 193         unsigned long flags;
 194
 195         pcistub_device_get(psdev);
 196
 197         spin_lock_irqsave(&psdev->lock, flags);
 198         if (!psdev->pdev) {
 199                 psdev->pdev = pdev;
 200                 pci_dev = psdev->dev;
 201         }
 202         spin_unlock_irqrestore(&psdev->lock, flags);
 203
 204         if (!pci_dev)
 205                 pcistub_device_put(psdev);
 206
 207         return pci_dev;
 208 }
 209
 210 struct pci_dev *pcistub_get_pci_dev_by_slot(struct xen_pcibk_device *pdev,
 211                                             int domain, int bus,
 212                                             int slot, int func)
 213 {
 214         struct pcistub_device *psdev;
 215         struct pci_dev *found_dev = NULL;
 216         unsigned long flags;
 217
 218         spin_lock_irqsave(&pcistub_devices_lock, flags);
 219
 220         psdev = pcistub_device_find_locked(domain, bus, slot, func);
 221         if (psdev)
 222                 found_dev = pcistub_device_get_pci_dev(pdev, psdev);
 223
 224         spin_unlock_irqrestore(&pcistub_devices_lock, flags);
 225         return found_dev;
 226 }
 227
 228 struct pci_dev *pcistub_get_pci_dev(struct xen_pcibk_device *pdev,
 229                                     struct pci_dev *dev)
 230 {
 231         struct pcistub_device *psdev;
 232         struct pci_dev *found_dev = NULL;
 233         unsigned long flags;
 234
 235         spin_lock_irqsave(&pcistub_devices_lock, flags);
 236
 237         list_for_each_entry(psdev, &pcistub_devices, dev_list) {
 238                 if (psdev->dev == dev) {
 239                         found_dev = pcistub_device_get_pci_dev(pdev, psdev);
 240                         break;
 241                 }
 242         }
 243
 244         spin_unlock_irqrestore(&pcistub_devices_lock, flags);
 245         return found_dev;
 246 }
 247
 248 /*
 249  * Called when:
 250  *  - XenBus state has been reconfigure (pci unplug). See xen_pcibk_remove_device
 251  *  - XenBus state has been disconnected (guest shutdown). See xen_pcibk_xenbus_remove
 252  *  - 'echo BDF > unbind' on pciback module with no guest attached. See pcistub_remove
 253  *  - 'echo BDF > unbind' with a guest still using it. See pcistub_remove
 254  *
 255  *  As such we have to be careful.
 256  *
 257  *  To make this easier, the caller has to hold the device lock.
 258  */
 259 void pcistub_put_pci_dev(struct pci_dev *dev)
 260 {
 261         struct pcistub_device *psdev, *found_psdev = NULL;
 262         unsigned long flags;
 263         struct xen_pcibk_dev_data *dev_data;
 264         int ret;
 265
 266         spin_lock_irqsave(&pcistub_devices_lock, flags);
 267
 268         list_for_each_entry(psdev, &pcistub_devices, dev_list) {
 269                 if (psdev->dev == dev) {
 270                         found_psdev = psdev;
 271                         break;
 272                 }
 273         }
 274
 275         spin_unlock_irqrestore(&pcistub_devices_lock, flags);
 276         if (WARN_ON(!found_psdev))
 277                 return;
 278
 279         /*hold this lock for avoiding breaking link between
 280         * pcistub and xen_pcibk when AER is in processing
 281         */
 282         down_write(&pcistub_sem);
 283         /* Cleanup our device
 284          * (so it's ready for the next domain)
 285          */
 286         device_lock_assert(&dev->dev);
 287         __pci_reset_function_locked(dev);
 288
 289         dev_data = pci_get_drvdata(dev);
 290         ret = pci_load_saved_state(dev, dev_data->pci_saved_state);
 291         if (!ret) {
 292                 /*
 293                  * The usual sequence is pci_save_state & pci_restore_state
 294                  * but the guest might have messed the configuration space up.
 295                  * Use the initial version (when device was bound to us).
 296                  */
 297                 pci_restore_state(dev);
 298         } else
 299                 dev_info(&dev->dev, "Could not reload PCI state\n");
 300         /* This disables the device. */
 301         xen_pcibk_reset_device(dev);
 302
 303         /* And cleanup up our emulated fields. */
 304         xen_pcibk_config_reset_dev(dev);
 305         xen_pcibk_config_free_dyn_fields(dev);
 306
 307         dev_data->allow_interrupt_control = 0;
 308
 309         xen_unregister_device_domain_owner(dev);
 310
 311         spin_lock_irqsave(&found_psdev->lock, flags);
 312         found_psdev->pdev = NULL;
 313         spin_unlock_irqrestore(&found_psdev->lock, flags);
 314
 315         pcistub_device_put(found_psdev);
 316         up_write(&pcistub_sem);
 317 }
 318
 319 static int pcistub_match_one(struct pci_dev *dev,
 320                              struct pcistub_device_id *pdev_id)
 321 {
 322         /* Match the specified device by domain, bus, slot, func and also if
 323          * any of the device's parent bridges match.
 324          */
 325         for (; dev != NULL; dev = dev->bus->self) {
 326                 if (pci_domain_nr(dev->bus) == pdev_id->domain
 327                     && dev->bus->number == pdev_id->bus
 328                     && dev->devfn == pdev_id->devfn)
 329                         return 1;
 330
 331                 /* Sometimes topmost bridge links to itself. */
 332                 if (dev == dev->bus->self)
 333                         break;
 334         }
 335
 336         return 0;
 337 }
 338
 339 static int pcistub_match(struct pci_dev *dev)
 340 {
 341         struct pcistub_device_id *pdev_id;
 342         unsigned long flags;
 343         int found = 0;
 344
 345         spin_lock_irqsave(&device_ids_lock, flags);
 346         list_for_each_entry(pdev_id, &pcistub_device_ids, slot_list) {
 347                 if (pcistub_match_one(dev, pdev_id)) {
 348                         found = 1;
 349                         break;
 350                 }
 351         }
 352         spin_unlock_irqrestore(&device_ids_lock, flags);
 353
 354         return found;
 355 }
 356
 357 static int pcistub_init_device(struct pci_dev *dev)
 358 {
 359         struct xen_pcibk_dev_data *dev_data;
 360         int err = 0;
 361
 362         dev_dbg(&dev->dev, "initializing...\n");
 363
 364         /* The PCI backend is not intended to be a module (or to work with
 365          * removable PCI devices (yet). If it were, xen_pcibk_config_free()
 366          * would need to be called somewhere to free the memory allocated
 367          * here and then to call kfree(pci_get_drvdata(psdev->dev)).
 368          */
 369         dev_data = kzalloc(sizeof(*dev_data) +  strlen(DRV_NAME "[]")
 370                                 + strlen(pci_name(dev)) + 1, GFP_KERNEL);
 371         if (!dev_data) {
 372                 err = -ENOMEM;
 373                 goto out;
 374         }
 375         pci_set_drvdata(dev, dev_data);
 376
 377         /*
 378          * Setup name for fake IRQ handler. It will only be enabled
 379          * once the device is turned on by the guest.
 380          */
 381         sprintf(dev_data->irq_name, DRV_NAME "[%s]", pci_name(dev));
 382
 383         dev_dbg(&dev->dev, "initializing config\n");
 384
 385         init_waitqueue_head(&xen_pcibk_aer_wait_queue);
 386         err = xen_pcibk_config_init_dev(dev);
 387         if (err)
 388                 goto out;
 389
 390         /* HACK: Force device (& ACPI) to determine what IRQ it's on - we
 391          * must do this here because pcibios_enable_device may specify
 392          * the pci device's true irq (and possibly its other resources)
 393          * if they differ from what's in the configuration space.
 394          * This makes the assumption that the device's resources won't
 395          * change after this point (otherwise this code may break!)
 396          */
 397         dev_dbg(&dev->dev, "enabling device\n");
 398         err = pci_enable_device(dev);
 399         if (err)
 400                 goto config_release;
 401
 402         if (dev->msix_cap) {
 403                 struct physdev_pci_device ppdev = {
 404                         .seg = pci_domain_nr(dev->bus),
 405                         .bus = dev->bus->number,
 406                         .devfn = dev->devfn
 407                 };
 408
 409                 err = HYPERVISOR_physdev_op(PHYSDEVOP_prepare_msix, &ppdev);
 410                 if (err && err != -ENOSYS)
 411                         dev_err(&dev->dev, "MSI-X preparation failed (%d)\n",
 412                                 err);
 413         }
 414
 415         /* We need the device active to save the state. */
 416         dev_dbg(&dev->dev, "save state of device\n");
 417         pci_save_state(dev);
 418         dev_data->pci_saved_state = pci_store_saved_state(dev);
 419         if (!dev_data->pci_saved_state)
 420                 dev_err(&dev->dev, "Could not store PCI conf saved state!\n");
 421         else {
 422                 dev_dbg(&dev->dev, "resetting (FLR, D3, etc) the device\n");
 423                 __pci_reset_function_locked(dev);
 424                 pci_restore_state(dev);
 425         }
 426         /* Now disable the device (this also ensures some private device
 427          * data is setup before we export)
 428          */
 429         dev_dbg(&dev->dev, "reset device\n");
 430         xen_pcibk_reset_device(dev);
 431
 432         pci_set_dev_assigned(dev);
 433         return 0;
 434
 435 config_release:
 436         xen_pcibk_config_free_dev(dev);
 437
 438 out:
 439         pci_set_drvdata(dev, NULL);
 440         kfree(dev_data);
 441         return err;
 442 }
 443
 444 /*
 445  * Because some initialization still happens on
 446  * devices during fs_initcall, we need to defer
 447  * full initialization of our devices until
 448  * device_initcall.
 449  */
 450 static int __init pcistub_init_devices_late(void)
 451 {
 452         struct pcistub_device *psdev;
 453         unsigned long flags;
 454         int err = 0;
 455
 456         spin_lock_irqsave(&pcistub_devices_lock, flags);
 457
 458         while (!list_empty(&seized_devices)) {
 459                 psdev = container_of(seized_devices.next,
 460                                      struct pcistub_device, dev_list);
 461                 list_del(&psdev->dev_list);
 462
 463                 spin_unlock_irqrestore(&pcistub_devices_lock, flags);
 464
 465                 err = pcistub_init_device(psdev->dev);
 466                 if (err) {
 467                         dev_err(&psdev->dev->dev,
 468                                 "error %d initializing device\n", err);
 469                         kfree(psdev);
 470                         psdev = NULL;
 471                 }
 472
 473                 spin_lock_irqsave(&pcistub_devices_lock, flags);
 474
 475                 if (psdev)
 476                         list_add_tail(&psdev->dev_list, &pcistub_devices);
 477         }
 478
 479         initialize_devices = 1;
 480
 481         spin_unlock_irqrestore(&pcistub_devices_lock, flags);
 482
 483         return 0;
 484 }
 485
 486 static void pcistub_device_id_add_list(struct pcistub_device_id *new,
 487                                        int domain, int bus, unsigned int devfn)
 488 {
 489         struct pcistub_device_id *pci_dev_id;
 490         unsigned long flags;
 491         int found = 0;
 492
 493         spin_lock_irqsave(&device_ids_lock, flags);
 494
 495         list_for_each_entry(pci_dev_id, &pcistub_device_ids, slot_list) {
 496                 if (pci_dev_id->domain == domain && pci_dev_id->bus == bus &&
 497                     pci_dev_id->devfn == devfn) {
 498                         found = 1;
 499                         break;
 500                 }
 501         }
 502
 503         if (!found) {
 504                 new->domain = domain;
 505                 new->bus = bus;
 506                 new->devfn = devfn;
 507                 list_add_tail(&new->slot_list, &pcistub_device_ids);
 508         }
 509
 510         spin_unlock_irqrestore(&device_ids_lock, flags);
 511
 512         if (found)
 513                 kfree(new);
 514 }
 515
 516 static int pcistub_seize(struct pci_dev *dev,
 517                          struct pcistub_device_id *pci_dev_id)
 518 {
 519         struct pcistub_device *psdev;
 520         unsigned long flags;
 521         int err = 0;
 522
 523         psdev = pcistub_device_alloc(dev);
 524         if (!psdev) {
 525                 kfree(pci_dev_id);
 526                 return -ENOMEM;
 527         }
 528
 529         spin_lock_irqsave(&pcistub_devices_lock, flags);
 530
 531         if (initialize_devices) {
 532                 spin_unlock_irqrestore(&pcistub_devices_lock, flags);
 533
 534                 /* don't want irqs disabled when calling pcistub_init_device */
 535                 err = pcistub_init_device(psdev->dev);
 536
 537                 spin_lock_irqsave(&pcistub_devices_lock, flags);
 538
 539                 if (!err)
 540                         list_add(&psdev->dev_list, &pcistub_devices);
 541         } else {
 542                 dev_dbg(&dev->dev, "deferring initialization\n");
 543                 list_add(&psdev->dev_list, &seized_devices);
 544         }
 545
 546         spin_unlock_irqrestore(&pcistub_devices_lock, flags);
 547
 548         if (err) {
 549                 kfree(pci_dev_id);
 550                 pcistub_device_put(psdev);
 551         } else if (pci_dev_id)
 552                 pcistub_device_id_add_list(pci_dev_id, pci_domain_nr(dev->bus),
 553                                            dev->bus->number, dev->devfn);
 554
 555         return err;
 556 }
 557
 558 /* Called when 'bind'. This means we must _NOT_ call pci_reset_function or
 559  * other functions that take the sysfs lock. */
 560 static int pcistub_probe(struct pci_dev *dev, const struct pci_device_id *id)
 561 {
 562         int err = 0, match;
 563         struct pcistub_device_id *pci_dev_id = NULL;
 564
 565         dev_dbg(&dev->dev, "probing...\n");
 566
 567         match = pcistub_match(dev);
 568
 569         if ((dev->driver_override &&
 570              !strcmp(dev->driver_override, PCISTUB_DRIVER_NAME)) ||
 571             match) {
 572
 573                 if (dev->hdr_type != PCI_HEADER_TYPE_NORMAL
 574                     && dev->hdr_type != PCI_HEADER_TYPE_BRIDGE) {
 575                         dev_err(&dev->dev, "can't export pci devices that "
 576                                 "don't have a normal (0) or bridge (1) "
 577                                 "header type!\n");
 578                         err = -ENODEV;
 579                         goto out;
 580                 }
 581
 582                 if (!match) {
 583                         pci_dev_id = kmalloc(sizeof(*pci_dev_id), GFP_KERNEL);
 584                         if (!pci_dev_id) {
 585                                 err = -ENOMEM;
 586                                 goto out;
 587                         }
 588                 }
 589
 590                 dev_info(&dev->dev, "seizing device\n");
 591                 err = pcistub_seize(dev, pci_dev_id);
 592         } else
 593                 /* Didn't find the device */
 594                 err = -ENODEV;
 595
 596 out:
 597         return err;
 598 }
 599
 600 /* Called when 'unbind'. This means we must _NOT_ call pci_reset_function or
 601  * other functions that take the sysfs lock. */
 602 static void pcistub_remove(struct pci_dev *dev)
 603 {
 604         struct pcistub_device *psdev, *found_psdev = NULL;
 605         unsigned long flags;
 606
 607         dev_dbg(&dev->dev, "removing\n");
 608
 609         spin_lock_irqsave(&pcistub_devices_lock, flags);
 610
 611         xen_pcibk_config_quirk_release(dev);
 612
 613         list_for_each_entry(psdev, &pcistub_devices, dev_list) {
 614                 if (psdev->dev == dev) {
 615                         found_psdev = psdev;
 616                         break;
 617                 }
 618         }
 619
 620         spin_unlock_irqrestore(&pcistub_devices_lock, flags);
 621
 622         if (found_psdev) {
 623                 dev_dbg(&dev->dev, "found device to remove %s\n",
 624                         found_psdev->pdev ? "- in-use" : "");
 625
 626                 if (found_psdev->pdev) {
 627                         int domid = xen_find_device_domain_owner(dev);
 628
 629                         pr_warn("****** removing device %s while still in-use by domain %d! ******\n",
 630                                pci_name(found_psdev->dev), domid);
 631                         pr_warn("****** driver domain may still access this device's i/o resources!\n");
 632                         pr_warn("****** shutdown driver domain before binding device\n");
 633                         pr_warn("****** to other drivers or domains\n");
 634
 635                         /* N.B. This ends up calling pcistub_put_pci_dev which ends up
 636                          * doing the FLR. */
 637                         xen_pcibk_release_pci_dev(found_psdev->pdev,
 638                                                 found_psdev->dev,
 639                                                 false /* caller holds the lock. */);
 640                 }
 641
 642                 spin_lock_irqsave(&pcistub_devices_lock, flags);
 643                 list_del(&found_psdev->dev_list);
 644                 spin_unlock_irqrestore(&pcistub_devices_lock, flags);
 645
 646                 /* the final put for releasing from the list */
 647                 pcistub_device_put(found_psdev);
 648         }
 649 }
 650
 651 static const struct pci_device_id pcistub_ids[] = {
 652         {
 653          .vendor = PCI_ANY_ID,
 654          .device = PCI_ANY_ID,
 655          .subvendor = PCI_ANY_ID,
 656          .subdevice = PCI_ANY_ID,
 657          },
 658         {0,},
 659 };
 660
 661 #define PCI_NODENAME_MAX 40
 662 static void kill_domain_by_device(struct pcistub_device *psdev)
 663 {
 664         struct xenbus_transaction xbt;
 665         int err;
 666         char nodename[PCI_NODENAME_MAX];
 667
 668         BUG_ON(!psdev);
 669         snprintf(nodename, PCI_NODENAME_MAX, "/local/domain/0/backend/pci/%d/0",
 670                 psdev->pdev->xdev->otherend_id);
 671
 672 again:
 673         err = xenbus_transaction_start(&xbt);
 674         if (err) {
 675                 dev_err(&psdev->dev->dev,
 676                         "error %d when start xenbus transaction\n", err);
 677                 return;
 678         }
 679         /*PV AER handlers will set this flag*/
 680         xenbus_printf(xbt, nodename, "aerState" , "aerfail");
 681         err = xenbus_transaction_end(xbt, 0);
 682         if (err) {
 683                 if (err == -EAGAIN)
 684                         goto again;
 685                 dev_err(&psdev->dev->dev,
 686                         "error %d when end xenbus transaction\n", err);
 687                 return;
 688         }
 689 }
 690
 691 /* For each aer recovery step error_detected, mmio_enabled, etc, front_end and
 692  * backend need to have cooperation. In xen_pcibk, those steps will do similar
 693  * jobs: send service request and waiting for front_end response.
 694 */
 695 static pci_ers_result_t common_process(struct pcistub_device *psdev,
 696                                        pci_channel_state_t state, int aer_cmd,
 697                                        pci_ers_result_t result)
 698 {
 699         pci_ers_result_t res = result;
 700         struct xen_pcie_aer_op *aer_op;
 701         struct xen_pcibk_device *pdev = psdev->pdev;
 702         struct xen_pci_sharedinfo *sh_info = pdev->sh_info;
 703         int ret;
 704
 705         /*with PV AER drivers*/
 706         aer_op = &(sh_info->aer_op);
 707         aer_op->cmd = aer_cmd ;
 708         /*useful for error_detected callback*/
 709         aer_op->err = state;
 710         /*pcifront_end BDF*/
 711         ret = xen_pcibk_get_pcifront_dev(psdev->dev, psdev->pdev,
 712                 &aer_op->domain, &aer_op->bus, &aer_op->devfn);
 713         if (!ret) {
 714                 dev_err(&psdev->dev->dev,
 715                         DRV_NAME ": failed to get pcifront device\n");
 716                 return PCI_ERS_RESULT_NONE;
 717         }
 718         wmb();
 719
 720         dev_dbg(&psdev->dev->dev,
 721                         DRV_NAME ": aer_op %x dom %x bus %x devfn %x\n",
 722                         aer_cmd, aer_op->domain, aer_op->bus, aer_op->devfn);
 723         /*local flag to mark there's aer request, xen_pcibk callback will use
 724         * this flag to judge whether we need to check pci-front give aer
 725         * service ack signal
 726         */
 727         set_bit(_PCIB_op_pending, (unsigned long *)&pdev->flags);
 728
 729         /*It is possible that a pcifront conf_read_write ops request invokes
 730         * the callback which cause the spurious execution of wake_up.
 731         * Yet it is harmless and better than a spinlock here
 732         */
 733         set_bit(_XEN_PCIB_active,
 734                 (unsigned long *)&sh_info->flags);
 735         wmb();
 736         notify_remote_via_irq(pdev->evtchn_irq);
 737
 738         ret = wait_event_timeout(xen_pcibk_aer_wait_queue,
 739                                  !(test_bit(_XEN_PCIB_active, (unsigned long *)
 740                                  &sh_info->flags)), 300*HZ);
 741
 742         if (!ret) {
 743                 if (test_bit(_XEN_PCIB_active,
 744                         (unsigned long *)&sh_info->flags)) {
 745                         dev_err(&psdev->dev->dev,
 746                                 "pcifront aer process not responding!\n");
 747                         clear_bit(_XEN_PCIB_active,
 748                           (unsigned long *)&sh_info->flags);
 749                         aer_op->err = PCI_ERS_RESULT_NONE;
 750                         return res;
 751                 }
 752         }
 753         clear_bit(_PCIB_op_pending, (unsigned long *)&pdev->flags);
 754
 755         if (test_bit(_XEN_PCIF_active,
 756                 (unsigned long *)&sh_info->flags)) {
 757                 dev_dbg(&psdev->dev->dev,
 758                         "schedule pci_conf service in " DRV_NAME "\n");
 759                 xen_pcibk_test_and_schedule_op(psdev->pdev);
 760         }
 761
 762         res = (pci_ers_result_t)aer_op->err;
 763         return res;
 764 }
 765
 766 /*
 767 * xen_pcibk_slot_reset: it will send the slot_reset request to  pcifront in case
 768 * of the device driver could provide this service, and then wait for pcifront
 769 * ack.
 770 * @dev: pointer to PCI devices
 771 * return value is used by aer_core do_recovery policy
 772 */
 773 static pci_ers_result_t xen_pcibk_slot_reset(struct pci_dev *dev)
 774 {
 775         struct pcistub_device *psdev;
 776         pci_ers_result_t result;
 777
 778         result = PCI_ERS_RESULT_RECOVERED;
 779         dev_dbg(&dev->dev, "xen_pcibk_slot_reset(bus:%x,devfn:%x)\n",
 780                 dev->bus->number, dev->devfn);
 781
 782         down_write(&pcistub_sem);
 783         psdev = pcistub_device_find(pci_domain_nr(dev->bus),
 784                                 dev->bus->number,
 785                                 PCI_SLOT(dev->devfn),
 786                                 PCI_FUNC(dev->devfn));
 787
 788         if (!psdev || !psdev->pdev) {
 789                 dev_err(&dev->dev,
 790                         DRV_NAME " device is not found/assigned\n");
 791                 goto end;
 792         }
 793
 794         if (!psdev->pdev->sh_info) {
 795                 dev_err(&dev->dev, DRV_NAME " device is not connected or owned"
 796                         " by HVM, kill it\n");
 797                 kill_domain_by_device(psdev);
 798                 goto end;
 799         }
 800
 801         if (!test_bit(_XEN_PCIB_AERHANDLER,
 802                 (unsigned long *)&psdev->pdev->sh_info->flags)) {
 803                 dev_err(&dev->dev,
 804                         "guest with no AER driver should have been killed\n");
 805                 goto end;
 806         }
 807         result = common_process(psdev, 1, XEN_PCI_OP_aer_slotreset, result);
 808
 809         if (result == PCI_ERS_RESULT_NONE ||
 810                 result == PCI_ERS_RESULT_DISCONNECT) {
 811                 dev_dbg(&dev->dev,
 812                         "No AER slot_reset service or disconnected!\n");
 813                 kill_domain_by_device(psdev);
 814         }
 815 end:
 816         if (psdev)
 817                 pcistub_device_put(psdev);
 818         up_write(&pcistub_sem);
 819         return result;
 820
 821 }
 822
 823
 824 /*xen_pcibk_mmio_enabled: it will send the mmio_enabled request to  pcifront
 825 * in case of the device driver could provide this service, and then wait
 826 * for pcifront ack
 827 * @dev: pointer to PCI devices
 828 * return value is used by aer_core do_recovery policy
 829 */
 830
 831 static pci_ers_result_t xen_pcibk_mmio_enabled(struct pci_dev *dev)
 832 {
 833         struct pcistub_device *psdev;
 834         pci_ers_result_t result;
 835
 836         result = PCI_ERS_RESULT_RECOVERED;
 837         dev_dbg(&dev->dev, "xen_pcibk_mmio_enabled(bus:%x,devfn:%x)\n",
 838                 dev->bus->number, dev->devfn);
 839
 840         down_write(&pcistub_sem);
 841         psdev = pcistub_device_find(pci_domain_nr(dev->bus),
 842                                 dev->bus->number,
 843                                 PCI_SLOT(dev->devfn),
 844                                 PCI_FUNC(dev->devfn));
 845
 846         if (!psdev || !psdev->pdev) {
 847                 dev_err(&dev->dev,
 848                         DRV_NAME " device is not found/assigned\n");
 849                 goto end;
 850         }
 851
 852         if (!psdev->pdev->sh_info) {
 853                 dev_err(&dev->dev, DRV_NAME " device is not connected or owned"
 854                         " by HVM, kill it\n");
 855                 kill_domain_by_device(psdev);
 856                 goto end;
 857         }
 858
 859         if (!test_bit(_XEN_PCIB_AERHANDLER,
 860                 (unsigned long *)&psdev->pdev->sh_info->flags)) {
 861                 dev_err(&dev->dev,
 862                         "guest with no AER driver should have been killed\n");
 863                 goto end;
 864         }
 865         result = common_process(psdev, 1, XEN_PCI_OP_aer_mmio, result);
 866
 867         if (result == PCI_ERS_RESULT_NONE ||
 868                 result == PCI_ERS_RESULT_DISCONNECT) {
 869                 dev_dbg(&dev->dev,
 870                         "No AER mmio_enabled service or disconnected!\n");
 871                 kill_domain_by_device(psdev);
 872         }
 873 end:
 874         if (psdev)
 875                 pcistub_device_put(psdev);
 876         up_write(&pcistub_sem);
 877         return result;
 878 }
 879
 880 /*xen_pcibk_error_detected: it will send the error_detected request to  pcifront
 881 * in case of the device driver could provide this service, and then wait
 882 * for pcifront ack.
 883 * @dev: pointer to PCI devices
 884 * @error: the current PCI connection state
 885 * return value is used by aer_core do_recovery policy
 886 */
 887
 888 static pci_ers_result_t xen_pcibk_error_detected(struct pci_dev *dev,
 889         pci_channel_state_t error)
 890 {
 891         struct pcistub_device *psdev;
 892         pci_ers_result_t result;
 893
 894         result = PCI_ERS_RESULT_CAN_RECOVER;
 895         dev_dbg(&dev->dev, "xen_pcibk_error_detected(bus:%x,devfn:%x)\n",
 896                 dev->bus->number, dev->devfn);
 897
 898         down_write(&pcistub_sem);
 899         psdev = pcistub_device_find(pci_domain_nr(dev->bus),
 900                                 dev->bus->number,
 901                                 PCI_SLOT(dev->devfn),
 902                                 PCI_FUNC(dev->devfn));
 903
 904         if (!psdev || !psdev->pdev) {
 905                 dev_err(&dev->dev,
 906                         DRV_NAME " device is not found/assigned\n");
 907                 goto end;
 908         }
 909
 910         if (!psdev->pdev->sh_info) {
 911                 dev_err(&dev->dev, DRV_NAME " device is not connected or owned"
 912                         " by HVM, kill it\n");
 913                 kill_domain_by_device(psdev);
 914                 goto end;
 915         }
 916
 917         /*Guest owns the device yet no aer handler regiested, kill guest*/
 918         if (!test_bit(_XEN_PCIB_AERHANDLER,
 919                 (unsigned long *)&psdev->pdev->sh_info->flags)) {
 920                 dev_dbg(&dev->dev, "guest may have no aer driver, kill it\n");
 921                 kill_domain_by_device(psdev);
 922                 goto end;
 923         }
 924         result = common_process(psdev, error, XEN_PCI_OP_aer_detected, result);
 925
 926         if (result == PCI_ERS_RESULT_NONE ||
 927                 result == PCI_ERS_RESULT_DISCONNECT) {
 928                 dev_dbg(&dev->dev,
 929                         "No AER error_detected service or disconnected!\n");
 930                 kill_domain_by_device(psdev);
 931         }
 932 end:
 933         if (psdev)
 934                 pcistub_device_put(psdev);
 935         up_write(&pcistub_sem);
 936         return result;
 937 }
 938
 939 /*xen_pcibk_error_resume: it will send the error_resume request to  pcifront
 940 * in case of the device driver could provide this service, and then wait
 941 * for pcifront ack.
 942 * @dev: pointer to PCI devices
 943 */
 944
 945 static void xen_pcibk_error_resume(struct pci_dev *dev)
 946 {
 947         struct pcistub_device *psdev;
 948
 949         dev_dbg(&dev->dev, "xen_pcibk_error_resume(bus:%x,devfn:%x)\n",
 950                 dev->bus->number, dev->devfn);
 951
 952         down_write(&pcistub_sem);
 953         psdev = pcistub_device_find(pci_domain_nr(dev->bus),
 954                                 dev->bus->number,
 955                                 PCI_SLOT(dev->devfn),
 956                                 PCI_FUNC(dev->devfn));
 957
 958         if (!psdev || !psdev->pdev) {
 959                 dev_err(&dev->dev,
 960                         DRV_NAME " device is not found/assigned\n");
 961                 goto end;
 962         }
 963
 964         if (!psdev->pdev->sh_info) {
 965                 dev_err(&dev->dev, DRV_NAME " device is not connected or owned"
 966                         " by HVM, kill it\n");
 967                 kill_domain_by_device(psdev);
 968                 goto end;
 969         }
 970
 971         if (!test_bit(_XEN_PCIB_AERHANDLER,
 972                 (unsigned long *)&psdev->pdev->sh_info->flags)) {
 973                 dev_err(&dev->dev,
 974                         "guest with no AER driver should have been killed\n");
 975                 kill_domain_by_device(psdev);
 976                 goto end;
 977         }
 978         common_process(psdev, 1, XEN_PCI_OP_aer_resume,
 979                        PCI_ERS_RESULT_RECOVERED);
 980 end:
 981         if (psdev)
 982                 pcistub_device_put(psdev);
 983         up_write(&pcistub_sem);
 984         return;
 985 }
 986
 987 /*add xen_pcibk AER handling*/
 988 static const struct pci_error_handlers xen_pcibk_error_handler = {
 989         .error_detected = xen_pcibk_error_detected,
 990         .mmio_enabled = xen_pcibk_mmio_enabled,
 991         .slot_reset = xen_pcibk_slot_reset,
 992         .resume = xen_pcibk_error_resume,
 993 };
 994
 995 /*
 996  * Note: There is no MODULE_DEVICE_TABLE entry here because this isn't
 997  * for a normal device. I don't want it to be loaded automatically.
 998  */
 999
1000 static struct pci_driver xen_pcibk_pci_driver = {
1001         /* The name should be xen_pciback, but until the tools are updated
1002          * we will keep it as pciback. */
1003         .name = PCISTUB_DRIVER_NAME,
1004         .id_table = pcistub_ids,
1005         .probe = pcistub_probe,
1006         .remove = pcistub_remove,
1007         .err_handler = &xen_pcibk_error_handler,
1008 };
1009
1010 static inline int str_to_slot(const char *buf, int *domain, int *bus,
1011                               int *slot, int *func)
1012 {
1013         int parsed = 0;
1014
1015         switch (sscanf(buf, " %x:%x:%x.%x %n", domain, bus, slot, func,
1016                        &parsed)) {
1017         case 3:
1018                 *func = -1;
1019                 sscanf(buf, " %x:%x:%x.* %n", domain, bus, slot, &parsed);
1020                 break;
1021         case 2:
1022                 *slot = *func = -1;
1023                 sscanf(buf, " %x:%x:*.* %n", domain, bus, &parsed);
1024                 break;
1025         }
1026         if (parsed && !buf[parsed])
1027                 return 0;
1028
1029         /* try again without domain */
1030         *domain = 0;
1031         switch (sscanf(buf, " %x:%x.%x %n", bus, slot, func, &parsed)) {
1032         case 2:
1033                 *func = -1;
1034                 sscanf(buf, " %x:%x.* %n", bus, slot, &parsed);
1035                 break;
1036         case 1:
1037                 *slot = *func = -1;
1038                 sscanf(buf, " %x:*.* %n", bus, &parsed);
1039                 break;
1040         }
1041         if (parsed && !buf[parsed])
1042                 return 0;
1043
1044         return -EINVAL;
1045 }
1046
1047 static inline int str_to_quirk(const char *buf, int *domain, int *bus, int
1048                                *slot, int *func, int *reg, int *size, int *mask)
1049 {
1050         int parsed = 0;
1051
1052         sscanf(buf, " %x:%x:%x.%x-%x:%x:%x %n", domain, bus, slot, func,
1053                reg, size, mask, &parsed);
1054         if (parsed && !buf[parsed])
1055                 return 0;
1056
1057         /* try again without domain */
1058         *domain = 0;
1059         sscanf(buf, " %x:%x.%x-%x:%x:%x %n", bus, slot, func, reg, size,
1060                mask, &parsed);
1061         if (parsed && !buf[parsed])
1062                 return 0;
1063
1064         return -EINVAL;
1065 }
1066
1067 static int pcistub_device_id_add(int domain, int bus, int slot, int func)
1068 {
1069         struct pcistub_device_id *pci_dev_id;
1070         int rc = 0, devfn = PCI_DEVFN(slot, func);
1071
1072         if (slot < 0) {
1073                 for (slot = 0; !rc && slot < 32; ++slot)
1074                         rc = pcistub_device_id_add(domain, bus, slot, func);
1075                 return rc;
1076         }
1077
1078         if (func < 0) {
1079                 for (func = 0; !rc && func < 8; ++func)
1080                         rc = pcistub_device_id_add(domain, bus, slot, func);
1081                 return rc;
1082         }
1083
1084         if ((
1085 #if !defined(MODULE) /* pci_domains_supported is not being exported */ \
1086     || !defined(CONFIG_PCI_DOMAINS)
1087              !pci_domains_supported ? domain :
1088 #endif
1089              domain < 0 || domain > 0xffff)
1090             || bus < 0 || bus > 0xff
1091             || PCI_SLOT(devfn) != slot
1092             || PCI_FUNC(devfn) != func)
1093                 return -EINVAL;
1094
1095         pci_dev_id = kmalloc(sizeof(*pci_dev_id), GFP_KERNEL);
1096         if (!pci_dev_id)
1097                 return -ENOMEM;
1098
1099         pr_debug("wants to seize %04x:%02x:%02x.%d\n",
1100                  domain, bus, slot, func);
1101
1102         pcistub_device_id_add_list(pci_dev_id, domain, bus, devfn);
1103
1104         return 0;
1105 }
1106
1107 static int pcistub_device_id_remove(int domain, int bus, int slot, int func)
1108 {
1109         struct pcistub_device_id *pci_dev_id, *t;
1110         int err = -ENOENT;
1111         unsigned long flags;
1112
1113         spin_lock_irqsave(&device_ids_lock, flags);
1114         list_for_each_entry_safe(pci_dev_id, t, &pcistub_device_ids,
1115                                  slot_list) {
1116                 if (pci_dev_id->domain == domain && pci_dev_id->bus == bus
1117                     && (slot < 0 || PCI_SLOT(pci_dev_id->devfn) == slot)
1118                     && (func < 0 || PCI_FUNC(pci_dev_id->devfn) == func)) {
1119                         /* Don't break; here because it's possible the same
1120                          * slot could be in the list more than once
1121                          */
1122                         list_del(&pci_dev_id->slot_list);
1123                         kfree(pci_dev_id);
1124
1125                         err = 0;
1126
1127                         pr_debug("removed %04x:%02x:%02x.%d from seize list\n",
1128                                  domain, bus, slot, func);
1129                 }
1130         }
1131         spin_unlock_irqrestore(&device_ids_lock, flags);
1132
1133         return err;
1134 }
1135
1136 static int pcistub_reg_add(int domain, int bus, int slot, int func,
1137                            unsigned int reg, unsigned int size,
1138                            unsigned int mask)
1139 {
1140         int err = 0;
1141         struct pcistub_device *psdev;
1142         struct pci_dev *dev;
1143         struct config_field *field;
1144
1145         if (reg > 0xfff || (size < 4 && (mask >> (size * 8))))
1146                 return -EINVAL;
1147
1148         psdev = pcistub_device_find(domain, bus, slot, func);
1149         if (!psdev) {
1150                 err = -ENODEV;
1151                 goto out;
1152         }
1153         dev = psdev->dev;
1154
1155         field = kzalloc(sizeof(*field), GFP_KERNEL);
1156         if (!field) {
1157                 err = -ENOMEM;
1158                 goto out;
1159         }
1160
1161         field->offset = reg;
1162         field->size = size;
1163         field->mask = mask;
1164         field->init = NULL;
1165         field->reset = NULL;
1166         field->release = NULL;
1167         field->clean = xen_pcibk_config_field_free;
1168
1169         err = xen_pcibk_config_quirks_add_field(dev, field);
1170         if (err)
1171                 kfree(field);
1172 out:
1173         if (psdev)
1174                 pcistub_device_put(psdev);
1175         return err;
1176 }
1177
1178 static ssize_t new_slot_store(struct device_driver *drv, const char *buf,
1179                               size_t count)
1180 {
1181         int domain, bus, slot, func;
1182         int err;
1183
1184         err = str_to_slot(buf, &domain, &bus, &slot, &func);
1185         if (err)
1186                 goto out;
1187
1188         err = pcistub_device_id_add(domain, bus, slot, func);
1189
1190 out:
1191         if (!err)
1192                 err = count;
1193         return err;
1194 }
1195 static DRIVER_ATTR_WO(new_slot);
1196
1197 static ssize_t remove_slot_store(struct device_driver *drv, const char *buf,
1198                                  size_t count)
1199 {
1200         int domain, bus, slot, func;
1201         int err;
1202
1203         err = str_to_slot(buf, &domain, &bus, &slot, &func);
1204         if (err)
1205                 goto out;
1206
1207         err = pcistub_device_id_remove(domain, bus, slot, func);
1208
1209 out:
1210         if (!err)
1211                 err = count;
1212         return err;
1213 }
1214 static DRIVER_ATTR_WO(remove_slot);
1215
1216 static ssize_t slots_show(struct device_driver *drv, char *buf)
1217 {
1218         struct pcistub_device_id *pci_dev_id;
1219         size_t count = 0;
1220         unsigned long flags;
1221
1222         spin_lock_irqsave(&device_ids_lock, flags);
1223         list_for_each_entry(pci_dev_id, &pcistub_device_ids, slot_list) {
1224                 if (count >= PAGE_SIZE)
1225                         break;
1226
1227                 count += scnprintf(buf + count, PAGE_SIZE - count,
1228                                    "%04x:%02x:%02x.%d\n",
1229                                    pci_dev_id->domain, pci_dev_id->bus,
1230                                    PCI_SLOT(pci_dev_id->devfn),
1231                                    PCI_FUNC(pci_dev_id->devfn));
1232         }
1233         spin_unlock_irqrestore(&device_ids_lock, flags);
1234
1235         return count;
1236 }
1237 static DRIVER_ATTR_RO(slots);
1238
1239 static ssize_t irq_handlers_show(struct device_driver *drv, char *buf)
1240 {
1241         struct pcistub_device *psdev;
1242         struct xen_pcibk_dev_data *dev_data;
1243         size_t count = 0;
1244         unsigned long flags;
1245
1246         spin_lock_irqsave(&pcistub_devices_lock, flags);
1247         list_for_each_entry(psdev, &pcistub_devices, dev_list) {
1248                 if (count >= PAGE_SIZE)
1249                         break;
1250                 if (!psdev->dev)
1251                         continue;
1252                 dev_data = pci_get_drvdata(psdev->dev);
1253                 if (!dev_data)
1254                         continue;
1255                 count +=
1256                     scnprintf(buf + count, PAGE_SIZE - count,
1257                               "%s:%s:%sing:%ld\n",
1258                               pci_name(psdev->dev),
1259                               dev_data->isr_on ? "on" : "off",
1260                               dev_data->ack_intr ? "ack" : "not ack",
1261                               dev_data->handled);
1262         }
1263         spin_unlock_irqrestore(&pcistub_devices_lock, flags);
1264         return count;
1265 }
1266 static DRIVER_ATTR_RO(irq_handlers);
1267
1268 static ssize_t irq_handler_state_store(struct device_driver *drv,
1269                                        const char *buf, size_t count)
1270 {
1271         struct pcistub_device *psdev;
1272         struct xen_pcibk_dev_data *dev_data;
1273         int domain, bus, slot, func;
1274         int err;
1275
1276         err = str_to_slot(buf, &domain, &bus, &slot, &func);
1277         if (err)
1278                 return err;
1279
1280         psdev = pcistub_device_find(domain, bus, slot, func);
1281         if (!psdev) {
1282                 err = -ENOENT;
1283                 goto out;
1284         }
1285
1286         dev_data = pci_get_drvdata(psdev->dev);
1287         if (!dev_data) {
1288                 err = -ENOENT;
1289                 goto out;
1290         }
1291
1292         dev_dbg(&psdev->dev->dev, "%s fake irq handler: %d->%d\n",
1293                 dev_data->irq_name, dev_data->isr_on,
1294                 !dev_data->isr_on);
1295
1296         dev_data->isr_on = !(dev_data->isr_on);
1297         if (dev_data->isr_on)
1298                 dev_data->ack_intr = 1;
1299 out:
1300         if (psdev)
1301                 pcistub_device_put(psdev);
1302         if (!err)
1303                 err = count;
1304         return err;
1305 }
1306 static DRIVER_ATTR_WO(irq_handler_state);
1307
1308 static ssize_t quirks_store(struct device_driver *drv, const char *buf,
1309                             size_t count)
1310 {
1311         int domain, bus, slot, func, reg, size, mask;
1312         int err;
1313
1314         err = str_to_quirk(buf, &domain, &bus, &slot, &func, &reg, &size,
1315                            &mask);
1316         if (err)
1317                 goto out;
1318
1319         err = pcistub_reg_add(domain, bus, slot, func, reg, size, mask);
1320
1321 out:
1322         if (!err)
1323                 err = count;
1324         return err;
1325 }
1326
1327 static ssize_t quirks_show(struct device_driver *drv, char *buf)
1328 {
1329         int count = 0;
1330         unsigned long flags;
1331         struct xen_pcibk_config_quirk *quirk;
1332         struct xen_pcibk_dev_data *dev_data;
1333         const struct config_field *field;
1334         const struct config_field_entry *cfg_entry;
1335
1336         spin_lock_irqsave(&device_ids_lock, flags);
1337         list_for_each_entry(quirk, &xen_pcibk_quirks, quirks_list) {
1338                 if (count >= PAGE_SIZE)
1339                         goto out;
1340
1341                 count += scnprintf(buf + count, PAGE_SIZE - count,
1342                                    "%02x:%02x.%01x\n\t%04x:%04x:%04x:%04x\n",
1343                                    quirk->pdev->bus->number,
1344                                    PCI_SLOT(quirk->pdev->devfn),
1345                                    PCI_FUNC(quirk->pdev->devfn),
1346                                    quirk->devid.vendor, quirk->devid.device,
1347                                    quirk->devid.subvendor,
1348                                    quirk->devid.subdevice);
1349
1350                 dev_data = pci_get_drvdata(quirk->pdev);
1351
1352                 list_for_each_entry(cfg_entry, &dev_data->config_fields, list) {
1353                         field = cfg_entry->field;
1354                         if (count >= PAGE_SIZE)
1355                                 goto out;
1356
1357                         count += scnprintf(buf + count, PAGE_SIZE - count,
1358                                            "\t\t%08x:%01x:%08x\n",
1359                                            cfg_entry->base_offset +
1360                                            field->offset, field->size,
1361                                            field->mask);
1362                 }
1363         }
1364
1365 out:
1366         spin_unlock_irqrestore(&device_ids_lock, flags);
1367
1368         return count;
1369 }
1370 static DRIVER_ATTR_RW(quirks);
1371
1372 static ssize_t permissive_store(struct device_driver *drv, const char *buf,
1373                                 size_t count)
1374 {
1375         int domain, bus, slot, func;
1376         int err;
1377         struct pcistub_device *psdev;
1378         struct xen_pcibk_dev_data *dev_data;
1379
1380         err = str_to_slot(buf, &domain, &bus, &slot, &func);
1381         if (err)
1382                 goto out;
1383
1384         psdev = pcistub_device_find(domain, bus, slot, func);
1385         if (!psdev) {
1386                 err = -ENODEV;
1387                 goto out;
1388         }
1389
1390         dev_data = pci_get_drvdata(psdev->dev);
1391         /* the driver data for a device should never be null at this point */
1392         if (!dev_data) {
1393                 err = -ENXIO;
1394                 goto release;
1395         }
1396         if (!dev_data->permissive) {
1397                 dev_data->permissive = 1;
1398                 /* Let user know that what they're doing could be unsafe */
1399                 dev_warn(&psdev->dev->dev, "enabling permissive mode "
1400                          "configuration space accesses!\n");
1401                 dev_warn(&psdev->dev->dev,
1402                          "permissive mode is potentially unsafe!\n");
1403         }
1404 release:
1405         pcistub_device_put(psdev);
1406 out:
1407         if (!err)
1408                 err = count;
1409         return err;
1410 }
1411
1412 static ssize_t permissive_show(struct device_driver *drv, char *buf)
1413 {
1414         struct pcistub_device *psdev;
1415         struct xen_pcibk_dev_data *dev_data;
1416         size_t count = 0;
1417         unsigned long flags;
1418         spin_lock_irqsave(&pcistub_devices_lock, flags);
1419         list_for_each_entry(psdev, &pcistub_devices, dev_list) {
1420                 if (count >= PAGE_SIZE)
1421                         break;
1422                 if (!psdev->dev)
1423                         continue;
1424                 dev_data = pci_get_drvdata(psdev->dev);
1425                 if (!dev_data || !dev_data->permissive)
1426                         continue;
1427                 count +=
1428                     scnprintf(buf + count, PAGE_SIZE - count, "%s\n",
1429                               pci_name(psdev->dev));
1430         }
1431         spin_unlock_irqrestore(&pcistub_devices_lock, flags);
1432         return count;
1433 }
1434 static DRIVER_ATTR_RW(permissive);
1435
1436 static ssize_t allow_interrupt_control_store(struct device_driver *drv,
1437                                              const char *buf, size_t count)
1438 {
1439         int domain, bus, slot, func;
1440         int err;
1441         struct pcistub_device *psdev;
1442         struct xen_pcibk_dev_data *dev_data;
1443
1444         err = str_to_slot(buf, &domain, &bus, &slot, &func);
1445         if (err)
1446                 goto out;
1447
1448         psdev = pcistub_device_find(domain, bus, slot, func);
1449         if (!psdev) {
1450                 err = -ENODEV;
1451                 goto out;
1452         }
1453
1454         dev_data = pci_get_drvdata(psdev->dev);
1455         /* the driver data for a device should never be null at this point */
1456         if (!dev_data) {
1457                 err = -ENXIO;
1458                 goto release;
1459         }
1460         dev_data->allow_interrupt_control = 1;
1461 release:
1462         pcistub_device_put(psdev);
1463 out:
1464         if (!err)
1465                 err = count;
1466         return err;
1467 }
1468
1469 static ssize_t allow_interrupt_control_show(struct device_driver *drv,
1470                                             char *buf)
1471 {
1472         struct pcistub_device *psdev;
1473         struct xen_pcibk_dev_data *dev_data;
1474         size_t count = 0;
1475         unsigned long flags;
1476
1477         spin_lock_irqsave(&pcistub_devices_lock, flags);
1478         list_for_each_entry(psdev, &pcistub_devices, dev_list) {
1479                 if (count >= PAGE_SIZE)
1480                         break;
1481                 if (!psdev->dev)
1482                         continue;
1483                 dev_data = pci_get_drvdata(psdev->dev);
1484                 if (!dev_data || !dev_data->allow_interrupt_control)
1485                         continue;
1486                 count +=
1487                     scnprintf(buf + count, PAGE_SIZE - count, "%s\n",
1488                               pci_name(psdev->dev));
1489         }
1490         spin_unlock_irqrestore(&pcistub_devices_lock, flags);
1491         return count;
1492 }
1493 static DRIVER_ATTR_RW(allow_interrupt_control);
1494
1495 static void pcistub_exit(void)
1496 {
1497         driver_remove_file(&xen_pcibk_pci_driver.driver, &driver_attr_new_slot);
1498         driver_remove_file(&xen_pcibk_pci_driver.driver,
1499                            &driver_attr_remove_slot);
1500         driver_remove_file(&xen_pcibk_pci_driver.driver, &driver_attr_slots);
1501         driver_remove_file(&xen_pcibk_pci_driver.driver, &driver_attr_quirks);
1502         driver_remove_file(&xen_pcibk_pci_driver.driver,
1503                            &driver_attr_permissive);
1504         driver_remove_file(&xen_pcibk_pci_driver.driver,
1505                            &driver_attr_allow_interrupt_control);
1506         driver_remove_file(&xen_pcibk_pci_driver.driver,
1507                            &driver_attr_irq_handlers);
1508         driver_remove_file(&xen_pcibk_pci_driver.driver,
1509                            &driver_attr_irq_handler_state);
1510         pci_unregister_driver(&xen_pcibk_pci_driver);
1511 }
1512
1513 static int __init pcistub_init(void)
1514 {
1515         int pos = 0;
1516         int err = 0;
1517         int domain, bus, slot, func;
1518         int parsed;
1519
1520         if (pci_devs_to_hide && *pci_devs_to_hide) {
1521                 do {
1522                         parsed = 0;
1523
1524                         err = sscanf(pci_devs_to_hide + pos,
1525                                      " (%x:%x:%x.%x) %n",
1526                                      &domain, &bus, &slot, &func, &parsed);
1527                         switch (err) {
1528                         case 3:
1529                                 func = -1;
1530                                 sscanf(pci_devs_to_hide + pos,
1531                                        " (%x:%x:%x.*) %n",
1532                                        &domain, &bus, &slot, &parsed);
1533                                 break;
1534                         case 2:
1535                                 slot = func = -1;
1536                                 sscanf(pci_devs_to_hide + pos,
1537                                        " (%x:%x:*.*) %n",
1538                                        &domain, &bus, &parsed);
1539                                 break;
1540                         }
1541
1542                         if (!parsed) {
1543                                 domain = 0;
1544                                 err = sscanf(pci_devs_to_hide + pos,
1545                                              " (%x:%x.%x) %n",
1546                                              &bus, &slot, &func, &parsed);
1547                                 switch (err) {
1548                                 case 2:
1549                                         func = -1;
1550                                         sscanf(pci_devs_to_hide + pos,
1551                                                " (%x:%x.*) %n",
1552                                                &bus, &slot, &parsed);
1553                                         break;
1554                                 case 1:
1555                                         slot = func = -1;
1556                                         sscanf(pci_devs_to_hide + pos,
1557                                                " (%x:*.*) %n",
1558                                                &bus, &parsed);
1559                                         break;
1560                                 }
1561                         }
1562
1563                         if (parsed <= 0)
1564                                 goto parse_error;
1565
1566                         err = pcistub_device_id_add(domain, bus, slot, func);
1567                         if (err)
1568                                 goto out;
1569
1570                         pos += parsed;
1571                 } while (pci_devs_to_hide[pos]);
1572         }
1573
1574         /* If we're the first PCI Device Driver to register, we're the
1575          * first one to get offered PCI devices as they become
1576          * available (and thus we can be the first to grab them)
1577          */
1578         err = pci_register_driver(&xen_pcibk_pci_driver);
1579         if (err < 0)
1580                 goto out;
1581
1582         err = driver_create_file(&xen_pcibk_pci_driver.driver,
1583                                  &driver_attr_new_slot);
1584         if (!err)
1585                 err = driver_create_file(&xen_pcibk_pci_driver.driver,
1586                                          &driver_attr_remove_slot);
1587         if (!err)
1588                 err = driver_create_file(&xen_pcibk_pci_driver.driver,
1589                                          &driver_attr_slots);
1590         if (!err)
1591                 err = driver_create_file(&xen_pcibk_pci_driver.driver,
1592                                          &driver_attr_quirks);
1593         if (!err)
1594                 err = driver_create_file(&xen_pcibk_pci_driver.driver,
1595                                          &driver_attr_permissive);
1596         if (!err)
1597                 err = driver_create_file(&xen_pcibk_pci_driver.driver,
1598                                          &driver_attr_allow_interrupt_control);
1599
1600         if (!err)
1601                 err = driver_create_file(&xen_pcibk_pci_driver.driver,
1602                                          &driver_attr_irq_handlers);
1603         if (!err)
1604                 err = driver_create_file(&xen_pcibk_pci_driver.driver,
1605                                         &driver_attr_irq_handler_state);
1606         if (err)
1607                 pcistub_exit();
1608
1609 out:
1610         return err;
1611
1612 parse_error:
1613         pr_err("Error parsing pci_devs_to_hide at \"%s\"\n",
1614                pci_devs_to_hide + pos);
1615         return -EINVAL;
1616 }
1617
1618 #ifndef MODULE
1619 /*
1620  * fs_initcall happens before device_initcall
1621  * so xen_pcibk *should* get called first (b/c we
1622  * want to suck up any device before other drivers
1623  * get a chance by being the first pci device
1624  * driver to register)
1625  */
1626 fs_initcall(pcistub_init);
1627 #endif
1628
1629 #ifdef CONFIG_PCI_IOV
1630 static struct pcistub_device *find_vfs(const struct pci_dev *pdev)
1631 {
1632         struct pcistub_device *psdev = NULL;
1633         unsigned long flags;
1634         bool found = false;
1635
1636         spin_lock_irqsave(&pcistub_devices_lock, flags);
1637         list_for_each_entry(psdev, &pcistub_devices, dev_list) {
1638                 if (!psdev->pdev && psdev->dev != pdev
1639                     && pci_physfn(psdev->dev) == pdev) {
1640                         found = true;
1641                         break;
1642                 }
1643         }
1644         spin_unlock_irqrestore(&pcistub_devices_lock, flags);
1645         if (found)
1646                 return psdev;
1647         return NULL;
1648 }
1649
1650 static int pci_stub_notifier(struct notifier_block *nb,
1651                              unsigned long action, void *data)
1652 {
1653         struct device *dev = data;
1654         const struct pci_dev *pdev = to_pci_dev(dev);
1655
1656         if (action != BUS_NOTIFY_UNBIND_DRIVER)
1657                 return NOTIFY_DONE;
1658
1659         if (!pdev->is_physfn)
1660                 return NOTIFY_DONE;
1661
1662         for (;;) {
1663                 struct pcistub_device *psdev = find_vfs(pdev);
1664                 if (!psdev)
1665                         break;
1666                 device_release_driver(&psdev->dev->dev);
1667         }
1668         return NOTIFY_DONE;
1669 }
1670
1671 static struct notifier_block pci_stub_nb = {
1672         .notifier_call = pci_stub_notifier,
1673 };
1674 #endif
1675
1676 static int __init xen_pcibk_init(void)
1677 {
1678         int err;
1679
1680         if (!xen_initial_domain())
1681                 return -ENODEV;
1682
1683         err = xen_pcibk_config_init();
1684         if (err)
1685                 return err;
1686
1687 #ifdef MODULE
1688         err = pcistub_init();
1689         if (err < 0)
1690                 return err;
1691 #endif
1692
1693         pcistub_init_devices_late();
1694         err = xen_pcibk_xenbus_register();
1695         if (err)
1696                 pcistub_exit();
1697 #ifdef CONFIG_PCI_IOV
1698         else
1699                 bus_register_notifier(&pci_bus_type, &pci_stub_nb);
1700 #endif
1701
1702         return err;
1703 }
1704
1705 static void __exit xen_pcibk_cleanup(void)
1706 {
1707 #ifdef CONFIG_PCI_IOV
1708         bus_unregister_notifier(&pci_bus_type, &pci_stub_nb);
1709 #endif
1710         xen_pcibk_xenbus_unregister();
1711         pcistub_exit();
1712 }
1713
1714 module_init(xen_pcibk_init);
1715 module_exit(xen_pcibk_cleanup);
1716
1717 MODULE_LICENSE("Dual BSD/GPL");
1718 MODULE_ALIAS("xen-backend:pci");