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 #define dev_fmt pr_fmt
  10
  11 #include <linux/module.h>
  12 #include <linux/init.h>
  13 #include <linux/rwsem.h>
  14 #include <linux/list.h>
  15 #include <linux/spinlock.h>
  16 #include <linux/kref.h>
  17 #include <linux/pci.h>
  18 #include <linux/wait.h>
  19 #include <linux/sched.h>
  20 #include <linux/atomic.h>
  21 #include <xen/events.h>
  22 #include <xen/pci.h>
  23 #include <xen/xen.h>
  24 #include <asm/xen/hypervisor.h>
  25 #include <xen/interface/physdev.h>
  26 #include "pciback.h"
  27 #include "conf_space.h"
  28 #include "conf_space_quirks.h"
  29
  30 #define PCISTUB_DRIVER_NAME "pciback"
  31
  32 static char *pci_devs_to_hide;
  33 wait_queue_head_t xen_pcibk_aer_wait_queue;
  34 /*Add sem for sync AER handling and xen_pcibk remove/reconfigue ops,
  35 * We want to avoid in middle of AER ops, xen_pcibk devices is being removed
  36 */
  37 static DECLARE_RWSEM(pcistub_sem);
  38 module_param_named(hide, pci_devs_to_hide, charp, 0444);
  39
  40 struct pcistub_device_id {
  41         struct list_head slot_list;
  42         int domain;
  43         unsigned char bus;
  44         unsigned int devfn;
  45 };
  46 static LIST_HEAD(pcistub_device_ids);
  47 static DEFINE_SPINLOCK(device_ids_lock);
  48
  49 struct pcistub_device {
  50         struct kref kref;
  51         struct list_head dev_list;
  52         spinlock_t lock;
  53
  54         struct pci_dev *dev;
  55         struct xen_pcibk_device *pdev;/* non-NULL if struct pci_dev is in use */
  56 };
  57
  58 /* Access to pcistub_devices & seized_devices lists and the initialize_devices
  59  * flag must be locked with pcistub_devices_lock
  60  */
  61 static DEFINE_SPINLOCK(pcistub_devices_lock);
  62 static LIST_HEAD(pcistub_devices);
  63
  64 /* wait for device_initcall before initializing our devices
  65  * (see pcistub_init_devices_late)
  66  */
  67 static int initialize_devices;
  68 static LIST_HEAD(seized_devices);
  69
  70 static struct pcistub_device *pcistub_device_alloc(struct pci_dev *dev)
  71 {
  72         struct pcistub_device *psdev;
  73
  74         dev_dbg(&dev->dev, "pcistub_device_alloc\n");
  75
  76         psdev = kzalloc(sizeof(*psdev), GFP_KERNEL);
  77         if (!psdev)
  78                 return NULL;
  79
  80         psdev->dev = pci_dev_get(dev);
  81         if (!psdev->dev) {
  82                 kfree(psdev);
  83                 return NULL;
  84         }
  85
  86         kref_init(&psdev->kref);
  87         spin_lock_init(&psdev->lock);
  88
  89         return psdev;
  90 }
  91
  92 /* Don't call this directly as it's called by pcistub_device_put */
  93 static void pcistub_device_release(struct kref *kref)
  94 {
  95         struct pcistub_device *psdev;
  96         struct pci_dev *dev;
  97         struct xen_pcibk_dev_data *dev_data;
  98
  99         psdev = container_of(kref, struct pcistub_device, kref);
 100         dev = psdev->dev;
 101         dev_data = pci_get_drvdata(dev);
 102
 103         dev_dbg(&dev->dev, "pcistub_device_release\n");
 104
 105         xen_unregister_device_domain_owner(dev);
 106
 107         /* Call the reset function which does not take lock as this
 108          * is called from "unbind" which takes a device_lock mutex.
 109          */
 110         __pci_reset_function_locked(dev);
 111         if (dev_data &&
 112             pci_load_and_free_saved_state(dev, &dev_data->pci_saved_state))
 113                 dev_info(&dev->dev, "Could not reload PCI state\n");
 114         else
 115                 pci_restore_state(dev);
 116
 117         if (dev->msix_cap) {
 118                 struct physdev_pci_device ppdev = {
 119                         .seg = pci_domain_nr(dev->bus),
 120                         .bus = dev->bus->number,
 121                         .devfn = dev->devfn
 122                 };
 123                 int err = HYPERVISOR_physdev_op(PHYSDEVOP_release_msix,
 124                                                 &ppdev);
 125
 126                 if (err && err != -ENOSYS)
 127                         dev_warn(&dev->dev, "MSI-X release failed (%d)\n",
 128                                  err);
 129         }
 130
 131         /* Disable the device */
 132         xen_pcibk_reset_device(dev);
 133
 134         kfree(dev_data);
 135         pci_set_drvdata(dev, NULL);
 136
 137         /* Clean-up the device */
 138         xen_pcibk_config_free_dyn_fields(dev);
 139         xen_pcibk_config_free_dev(dev);
 140
 141         pci_clear_dev_assigned(dev);
 142         pci_dev_put(dev);
 143
 144         kfree(psdev);
 145 }
 146
 147 static inline void pcistub_device_get(struct pcistub_device *psdev)
 148 {
 149         kref_get(&psdev->kref);
 150 }
 151
 152 static inline void pcistub_device_put(struct pcistub_device *psdev)
 153 {
 154         kref_put(&psdev->kref, pcistub_device_release);
 155 }
 156
 157 static struct pcistub_device *pcistub_device_find_locked(int domain, int bus,
 158                                                          int slot, int func)
 159 {
 160         struct pcistub_device *psdev;
 161
 162         list_for_each_entry(psdev, &pcistub_devices, dev_list) {
 163                 if (psdev->dev != NULL
 164                     && domain == pci_domain_nr(psdev->dev->bus)
 165                     && bus == psdev->dev->bus->number
 166                     && slot == PCI_SLOT(psdev->dev->devfn)
 167                     && func == PCI_FUNC(psdev->dev->devfn)) {
 168                         return psdev;
 169                 }
 170         }
 171
 172         return NULL;
 173 }
 174
 175 static struct pcistub_device *pcistub_device_find(int domain, int bus,
 176                                                   int slot, int func)
 177 {
 178         struct pcistub_device *psdev;
 179         unsigned long flags;
 180
 181         spin_lock_irqsave(&pcistub_devices_lock, flags);
 182
 183         psdev = pcistub_device_find_locked(domain, bus, slot, func);
 184         if (psdev)
 185                 pcistub_device_get(psdev);
 186
 187         spin_unlock_irqrestore(&pcistub_devices_lock, flags);
 188         return psdev;
 189 }
 190
 191 static struct pci_dev *pcistub_device_get_pci_dev(struct xen_pcibk_device *pdev,
 192                                                   struct pcistub_device *psdev)
 193 {
 194         struct pci_dev *pci_dev = NULL;
 195         unsigned long flags;
 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_get(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                         dev_warn(&dev->dev, "****** removing device %s while still in-use by domain %d! ******\n",
 630                                pci_name(found_psdev->dev), domid);
 631                         dev_warn(&dev->dev, "****** driver domain may still access this device's i/o resources!\n");
 632                         dev_warn(&dev->dev, "****** shutdown driver domain before binding device\n");
 633                         dev_warn(&dev->dev, "****** 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, "failed to get pcifront device\n");
 715                 return PCI_ERS_RESULT_NONE;
 716         }
 717         wmb();
 718
 719         dev_dbg(&psdev->dev->dev, "aer_op %x dom %x bus %x devfn %x\n",
 720                         aer_cmd, aer_op->domain, aer_op->bus, aer_op->devfn);
 721         /*local flag to mark there's aer request, xen_pcibk callback will use
 722         * this flag to judge whether we need to check pci-front give aer
 723         * service ack signal
 724         */
 725         set_bit(_PCIB_op_pending, (unsigned long *)&pdev->flags);
 726
 727         /*It is possible that a pcifront conf_read_write ops request invokes
 728         * the callback which cause the spurious execution of wake_up.
 729         * Yet it is harmless and better than a spinlock here
 730         */
 731         set_bit(_XEN_PCIB_active,
 732                 (unsigned long *)&sh_info->flags);
 733         wmb();
 734         notify_remote_via_irq(pdev->evtchn_irq);
 735
 736         /* Enable IRQ to signal "request done". */
 737         xen_pcibk_lateeoi(pdev, 0);
 738
 739         ret = wait_event_timeout(xen_pcibk_aer_wait_queue,
 740                                  !(test_bit(_XEN_PCIB_active, (unsigned long *)
 741                                  &sh_info->flags)), 300*HZ);
 742
 743         /* Enable IRQ for pcifront request if not already active. */
 744         if (!test_bit(_PDEVF_op_active, &pdev->flags))
 745                 xen_pcibk_lateeoi(pdev, 0);
 746
 747         if (!ret) {
 748                 if (test_bit(_XEN_PCIB_active,
 749                         (unsigned long *)&sh_info->flags)) {
 750                         dev_err(&psdev->dev->dev,
 751                                 "pcifront aer process not responding!\n");
 752                         clear_bit(_XEN_PCIB_active,
 753                           (unsigned long *)&sh_info->flags);
 754                         aer_op->err = PCI_ERS_RESULT_NONE;
 755                         return res;
 756                 }
 757         }
 758         clear_bit(_PCIB_op_pending, (unsigned long *)&pdev->flags);
 759
 760         res = (pci_ers_result_t)aer_op->err;
 761         return res;
 762 }
 763
 764 /*
 765 * xen_pcibk_slot_reset: it will send the slot_reset request to  pcifront in case
 766 * of the device driver could provide this service, and then wait for pcifront
 767 * ack.
 768 * @dev: pointer to PCI devices
 769 * return value is used by aer_core do_recovery policy
 770 */
 771 static pci_ers_result_t xen_pcibk_slot_reset(struct pci_dev *dev)
 772 {
 773         struct pcistub_device *psdev;
 774         pci_ers_result_t result;
 775
 776         result = PCI_ERS_RESULT_RECOVERED;
 777         dev_dbg(&dev->dev, "xen_pcibk_slot_reset(bus:%x,devfn:%x)\n",
 778                 dev->bus->number, dev->devfn);
 779
 780         down_write(&pcistub_sem);
 781         psdev = pcistub_device_find(pci_domain_nr(dev->bus),
 782                                 dev->bus->number,
 783                                 PCI_SLOT(dev->devfn),
 784                                 PCI_FUNC(dev->devfn));
 785
 786         if (!psdev || !psdev->pdev) {
 787                 dev_err(&dev->dev, "device is not found/assigned\n");
 788                 goto end;
 789         }
 790
 791         if (!psdev->pdev->sh_info) {
 792                 dev_err(&dev->dev, "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, pci_channel_io_normal, 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, "device is not found/assigned\n");
 845                 goto end;
 846         }
 847
 848         if (!psdev->pdev->sh_info) {
 849                 dev_err(&dev->dev, "device is not connected or owned"
 850                         " by HVM, kill it\n");
 851                 kill_domain_by_device(psdev);
 852                 goto end;
 853         }
 854
 855         if (!test_bit(_XEN_PCIB_AERHANDLER,
 856                 (unsigned long *)&psdev->pdev->sh_info->flags)) {
 857                 dev_err(&dev->dev,
 858                         "guest with no AER driver should have been killed\n");
 859                 goto end;
 860         }
 861         result = common_process(psdev, pci_channel_io_normal, XEN_PCI_OP_aer_mmio, result);
 862
 863         if (result == PCI_ERS_RESULT_NONE ||
 864                 result == PCI_ERS_RESULT_DISCONNECT) {
 865                 dev_dbg(&dev->dev,
 866                         "No AER mmio_enabled service or disconnected!\n");
 867                 kill_domain_by_device(psdev);
 868         }
 869 end:
 870         if (psdev)
 871                 pcistub_device_put(psdev);
 872         up_write(&pcistub_sem);
 873         return result;
 874 }
 875
 876 /*xen_pcibk_error_detected: it will send the error_detected request to  pcifront
 877 * in case of the device driver could provide this service, and then wait
 878 * for pcifront ack.
 879 * @dev: pointer to PCI devices
 880 * @error: the current PCI connection state
 881 * return value is used by aer_core do_recovery policy
 882 */
 883
 884 static pci_ers_result_t xen_pcibk_error_detected(struct pci_dev *dev,
 885         pci_channel_state_t error)
 886 {
 887         struct pcistub_device *psdev;
 888         pci_ers_result_t result;
 889
 890         result = PCI_ERS_RESULT_CAN_RECOVER;
 891         dev_dbg(&dev->dev, "xen_pcibk_error_detected(bus:%x,devfn:%x)\n",
 892                 dev->bus->number, dev->devfn);
 893
 894         down_write(&pcistub_sem);
 895         psdev = pcistub_device_find(pci_domain_nr(dev->bus),
 896                                 dev->bus->number,
 897                                 PCI_SLOT(dev->devfn),
 898                                 PCI_FUNC(dev->devfn));
 899
 900         if (!psdev || !psdev->pdev) {
 901                 dev_err(&dev->dev, "device is not found/assigned\n");
 902                 goto end;
 903         }
 904
 905         if (!psdev->pdev->sh_info) {
 906                 dev_err(&dev->dev, "device is not connected or owned"
 907                         " by HVM, kill it\n");
 908                 kill_domain_by_device(psdev);
 909                 goto end;
 910         }
 911
 912         /*Guest owns the device yet no aer handler regiested, kill guest*/
 913         if (!test_bit(_XEN_PCIB_AERHANDLER,
 914                 (unsigned long *)&psdev->pdev->sh_info->flags)) {
 915                 dev_dbg(&dev->dev, "guest may have no aer driver, kill it\n");
 916                 kill_domain_by_device(psdev);
 917                 goto end;
 918         }
 919         result = common_process(psdev, error, XEN_PCI_OP_aer_detected, result);
 920
 921         if (result == PCI_ERS_RESULT_NONE ||
 922                 result == PCI_ERS_RESULT_DISCONNECT) {
 923                 dev_dbg(&dev->dev,
 924                         "No AER error_detected service or disconnected!\n");
 925                 kill_domain_by_device(psdev);
 926         }
 927 end:
 928         if (psdev)
 929                 pcistub_device_put(psdev);
 930         up_write(&pcistub_sem);
 931         return result;
 932 }
 933
 934 /*xen_pcibk_error_resume: it will send the error_resume request to  pcifront
 935 * in case of the device driver could provide this service, and then wait
 936 * for pcifront ack.
 937 * @dev: pointer to PCI devices
 938 */
 939
 940 static void xen_pcibk_error_resume(struct pci_dev *dev)
 941 {
 942         struct pcistub_device *psdev;
 943
 944         dev_dbg(&dev->dev, "xen_pcibk_error_resume(bus:%x,devfn:%x)\n",
 945                 dev->bus->number, dev->devfn);
 946
 947         down_write(&pcistub_sem);
 948         psdev = pcistub_device_find(pci_domain_nr(dev->bus),
 949                                 dev->bus->number,
 950                                 PCI_SLOT(dev->devfn),
 951                                 PCI_FUNC(dev->devfn));
 952
 953         if (!psdev || !psdev->pdev) {
 954                 dev_err(&dev->dev, "device is not found/assigned\n");
 955                 goto end;
 956         }
 957
 958         if (!psdev->pdev->sh_info) {
 959                 dev_err(&dev->dev, "device is not connected or owned"
 960                         " by HVM, kill it\n");
 961                 kill_domain_by_device(psdev);
 962                 goto end;
 963         }
 964
 965         if (!test_bit(_XEN_PCIB_AERHANDLER,
 966                 (unsigned long *)&psdev->pdev->sh_info->flags)) {
 967                 dev_err(&dev->dev,
 968                         "guest with no AER driver should have been killed\n");
 969                 kill_domain_by_device(psdev);
 970                 goto end;
 971         }
 972         common_process(psdev, pci_channel_io_normal, XEN_PCI_OP_aer_resume,
 973                        PCI_ERS_RESULT_RECOVERED);
 974 end:
 975         if (psdev)
 976                 pcistub_device_put(psdev);
 977         up_write(&pcistub_sem);
 978         return;
 979 }
 980
 981 /*add xen_pcibk AER handling*/
 982 static const struct pci_error_handlers xen_pcibk_error_handler = {
 983         .error_detected = xen_pcibk_error_detected,
 984         .mmio_enabled = xen_pcibk_mmio_enabled,
 985         .slot_reset = xen_pcibk_slot_reset,
 986         .resume = xen_pcibk_error_resume,
 987 };
 988
 989 /*
 990  * Note: There is no MODULE_DEVICE_TABLE entry here because this isn't
 991  * for a normal device. I don't want it to be loaded automatically.
 992  */
 993
 994 static struct pci_driver xen_pcibk_pci_driver = {
 995         /* The name should be xen_pciback, but until the tools are updated
 996          * we will keep it as pciback. */
 997         .name = PCISTUB_DRIVER_NAME,
 998         .id_table = pcistub_ids,
 999         .probe = pcistub_probe,
1000         .remove = pcistub_remove,
1001         .err_handler = &xen_pcibk_error_handler,
1002 };
1003
1004 static inline int str_to_slot(const char *buf, int *domain, int *bus,
1005                               int *slot, int *func)
1006 {
1007         int parsed = 0;
1008
1009         switch (sscanf(buf, " %x:%x:%x.%x %n", domain, bus, slot, func,
1010                        &parsed)) {
1011         case 3:
1012                 *func = -1;
1013                 sscanf(buf, " %x:%x:%x.* %n", domain, bus, slot, &parsed);
1014                 break;
1015         case 2:
1016                 *slot = *func = -1;
1017                 sscanf(buf, " %x:%x:*.* %n", domain, bus, &parsed);
1018                 break;
1019         }
1020         if (parsed && !buf[parsed])
1021                 return 0;
1022
1023         /* try again without domain */
1024         *domain = 0;
1025         switch (sscanf(buf, " %x:%x.%x %n", bus, slot, func, &parsed)) {
1026         case 2:
1027                 *func = -1;
1028                 sscanf(buf, " %x:%x.* %n", bus, slot, &parsed);
1029                 break;
1030         case 1:
1031                 *slot = *func = -1;
1032                 sscanf(buf, " %x:*.* %n", bus, &parsed);
1033                 break;
1034         }
1035         if (parsed && !buf[parsed])
1036                 return 0;
1037
1038         return -EINVAL;
1039 }
1040
1041 static inline int str_to_quirk(const char *buf, int *domain, int *bus, int
1042                                *slot, int *func, int *reg, int *size, int *mask)
1043 {
1044         int parsed = 0;
1045
1046         sscanf(buf, " %x:%x:%x.%x-%x:%x:%x %n", domain, bus, slot, func,
1047                reg, size, mask, &parsed);
1048         if (parsed && !buf[parsed])
1049                 return 0;
1050
1051         /* try again without domain */
1052         *domain = 0;
1053         sscanf(buf, " %x:%x.%x-%x:%x:%x %n", bus, slot, func, reg, size,
1054                mask, &parsed);
1055         if (parsed && !buf[parsed])
1056                 return 0;
1057
1058         return -EINVAL;
1059 }
1060
1061 static int pcistub_device_id_add(int domain, int bus, int slot, int func)
1062 {
1063         struct pcistub_device_id *pci_dev_id;
1064         int rc = 0, devfn = PCI_DEVFN(slot, func);
1065
1066         if (slot < 0) {
1067                 for (slot = 0; !rc && slot < 32; ++slot)
1068                         rc = pcistub_device_id_add(domain, bus, slot, func);
1069                 return rc;
1070         }
1071
1072         if (func < 0) {
1073                 for (func = 0; !rc && func < 8; ++func)
1074                         rc = pcistub_device_id_add(domain, bus, slot, func);
1075                 return rc;
1076         }
1077
1078         if ((
1079 #if !defined(MODULE) /* pci_domains_supported is not being exported */ \
1080     || !defined(CONFIG_PCI_DOMAINS)
1081              !pci_domains_supported ? domain :
1082 #endif
1083              domain < 0 || domain > 0xffff)
1084             || bus < 0 || bus > 0xff
1085             || PCI_SLOT(devfn) != slot
1086             || PCI_FUNC(devfn) != func)
1087                 return -EINVAL;
1088
1089         pci_dev_id = kmalloc(sizeof(*pci_dev_id), GFP_KERNEL);
1090         if (!pci_dev_id)
1091                 return -ENOMEM;
1092
1093         pr_debug("wants to seize %04x:%02x:%02x.%d\n",
1094                  domain, bus, slot, func);
1095
1096         pcistub_device_id_add_list(pci_dev_id, domain, bus, devfn);
1097
1098         return 0;
1099 }
1100
1101 static int pcistub_device_id_remove(int domain, int bus, int slot, int func)
1102 {
1103         struct pcistub_device_id *pci_dev_id, *t;
1104         int err = -ENOENT;
1105         unsigned long flags;
1106
1107         spin_lock_irqsave(&device_ids_lock, flags);
1108         list_for_each_entry_safe(pci_dev_id, t, &pcistub_device_ids,
1109                                  slot_list) {
1110                 if (pci_dev_id->domain == domain && pci_dev_id->bus == bus
1111                     && (slot < 0 || PCI_SLOT(pci_dev_id->devfn) == slot)
1112                     && (func < 0 || PCI_FUNC(pci_dev_id->devfn) == func)) {
1113                         /* Don't break; here because it's possible the same
1114                          * slot could be in the list more than once
1115                          */
1116                         list_del(&pci_dev_id->slot_list);
1117                         kfree(pci_dev_id);
1118
1119                         err = 0;
1120
1121                         pr_debug("removed %04x:%02x:%02x.%d from seize list\n",
1122                                  domain, bus, slot, func);
1123                 }
1124         }
1125         spin_unlock_irqrestore(&device_ids_lock, flags);
1126
1127         return err;
1128 }
1129
1130 static int pcistub_reg_add(int domain, int bus, int slot, int func,
1131                            unsigned int reg, unsigned int size,
1132                            unsigned int mask)
1133 {
1134         int err = 0;
1135         struct pcistub_device *psdev;
1136         struct pci_dev *dev;
1137         struct config_field *field;
1138
1139         if (reg > 0xfff || (size < 4 && (mask >> (size * 8))))
1140                 return -EINVAL;
1141
1142         psdev = pcistub_device_find(domain, bus, slot, func);
1143         if (!psdev) {
1144                 err = -ENODEV;
1145                 goto out;
1146         }
1147         dev = psdev->dev;
1148
1149         field = kzalloc(sizeof(*field), GFP_KERNEL);
1150         if (!field) {
1151                 err = -ENOMEM;
1152                 goto out;
1153         }
1154
1155         field->offset = reg;
1156         field->size = size;
1157         field->mask = mask;
1158         field->init = NULL;
1159         field->reset = NULL;
1160         field->release = NULL;
1161         field->clean = xen_pcibk_config_field_free;
1162
1163         err = xen_pcibk_config_quirks_add_field(dev, field);
1164         if (err)
1165                 kfree(field);
1166 out:
1167         if (psdev)
1168                 pcistub_device_put(psdev);
1169         return err;
1170 }
1171
1172 static ssize_t new_slot_store(struct device_driver *drv, const char *buf,
1173                               size_t count)
1174 {
1175         int domain, bus, slot, func;
1176         int err;
1177
1178         err = str_to_slot(buf, &domain, &bus, &slot, &func);
1179         if (err)
1180                 goto out;
1181
1182         err = pcistub_device_id_add(domain, bus, slot, func);
1183
1184 out:
1185         if (!err)
1186                 err = count;
1187         return err;
1188 }
1189 static DRIVER_ATTR_WO(new_slot);
1190
1191 static ssize_t remove_slot_store(struct device_driver *drv, const char *buf,
1192                                  size_t count)
1193 {
1194         int domain, bus, slot, func;
1195         int err;
1196
1197         err = str_to_slot(buf, &domain, &bus, &slot, &func);
1198         if (err)
1199                 goto out;
1200
1201         err = pcistub_device_id_remove(domain, bus, slot, func);
1202
1203 out:
1204         if (!err)
1205                 err = count;
1206         return err;
1207 }
1208 static DRIVER_ATTR_WO(remove_slot);
1209
1210 static ssize_t slots_show(struct device_driver *drv, char *buf)
1211 {
1212         struct pcistub_device_id *pci_dev_id;
1213         size_t count = 0;
1214         unsigned long flags;
1215
1216         spin_lock_irqsave(&device_ids_lock, flags);
1217         list_for_each_entry(pci_dev_id, &pcistub_device_ids, slot_list) {
1218                 if (count >= PAGE_SIZE)
1219                         break;
1220
1221                 count += scnprintf(buf + count, PAGE_SIZE - count,
1222                                    "%04x:%02x:%02x.%d\n",
1223                                    pci_dev_id->domain, pci_dev_id->bus,
1224                                    PCI_SLOT(pci_dev_id->devfn),
1225                                    PCI_FUNC(pci_dev_id->devfn));
1226         }
1227         spin_unlock_irqrestore(&device_ids_lock, flags);
1228
1229         return count;
1230 }
1231 static DRIVER_ATTR_RO(slots);
1232
1233 static ssize_t irq_handlers_show(struct device_driver *drv, char *buf)
1234 {
1235         struct pcistub_device *psdev;
1236         struct xen_pcibk_dev_data *dev_data;
1237         size_t count = 0;
1238         unsigned long flags;
1239
1240         spin_lock_irqsave(&pcistub_devices_lock, flags);
1241         list_for_each_entry(psdev, &pcistub_devices, dev_list) {
1242                 if (count >= PAGE_SIZE)
1243                         break;
1244                 if (!psdev->dev)
1245                         continue;
1246                 dev_data = pci_get_drvdata(psdev->dev);
1247                 if (!dev_data)
1248                         continue;
1249                 count +=
1250                     scnprintf(buf + count, PAGE_SIZE - count,
1251                               "%s:%s:%sing:%ld\n",
1252                               pci_name(psdev->dev),
1253                               dev_data->isr_on ? "on" : "off",
1254                               dev_data->ack_intr ? "ack" : "not ack",
1255                               dev_data->handled);
1256         }
1257         spin_unlock_irqrestore(&pcistub_devices_lock, flags);
1258         return count;
1259 }
1260 static DRIVER_ATTR_RO(irq_handlers);
1261
1262 static ssize_t irq_handler_state_store(struct device_driver *drv,
1263                                        const char *buf, size_t count)
1264 {
1265         struct pcistub_device *psdev;
1266         struct xen_pcibk_dev_data *dev_data;
1267         int domain, bus, slot, func;
1268         int err;
1269
1270         err = str_to_slot(buf, &domain, &bus, &slot, &func);
1271         if (err)
1272                 return err;
1273
1274         psdev = pcistub_device_find(domain, bus, slot, func);
1275         if (!psdev) {
1276                 err = -ENOENT;
1277                 goto out;
1278         }
1279
1280         dev_data = pci_get_drvdata(psdev->dev);
1281         if (!dev_data) {
1282                 err = -ENOENT;
1283                 goto out;
1284         }
1285
1286         dev_dbg(&psdev->dev->dev, "%s fake irq handler: %d->%d\n",
1287                 dev_data->irq_name, dev_data->isr_on,
1288                 !dev_data->isr_on);
1289
1290         dev_data->isr_on = !(dev_data->isr_on);
1291         if (dev_data->isr_on)
1292                 dev_data->ack_intr = 1;
1293 out:
1294         if (psdev)
1295                 pcistub_device_put(psdev);
1296         if (!err)
1297                 err = count;
1298         return err;
1299 }
1300 static DRIVER_ATTR_WO(irq_handler_state);
1301
1302 static ssize_t quirks_store(struct device_driver *drv, const char *buf,
1303                             size_t count)
1304 {
1305         int domain, bus, slot, func, reg, size, mask;
1306         int err;
1307
1308         err = str_to_quirk(buf, &domain, &bus, &slot, &func, &reg, &size,
1309                            &mask);
1310         if (err)
1311                 goto out;
1312
1313         err = pcistub_reg_add(domain, bus, slot, func, reg, size, mask);
1314
1315 out:
1316         if (!err)
1317                 err = count;
1318         return err;
1319 }
1320
1321 static ssize_t quirks_show(struct device_driver *drv, char *buf)
1322 {
1323         int count = 0;
1324         unsigned long flags;
1325         struct xen_pcibk_config_quirk *quirk;
1326         struct xen_pcibk_dev_data *dev_data;
1327         const struct config_field *field;
1328         const struct config_field_entry *cfg_entry;
1329
1330         spin_lock_irqsave(&device_ids_lock, flags);
1331         list_for_each_entry(quirk, &xen_pcibk_quirks, quirks_list) {
1332                 if (count >= PAGE_SIZE)
1333                         goto out;
1334
1335                 count += scnprintf(buf + count, PAGE_SIZE - count,
1336                                    "%02x:%02x.%01x\n\t%04x:%04x:%04x:%04x\n",
1337                                    quirk->pdev->bus->number,
1338                                    PCI_SLOT(quirk->pdev->devfn),
1339                                    PCI_FUNC(quirk->pdev->devfn),
1340                                    quirk->devid.vendor, quirk->devid.device,
1341                                    quirk->devid.subvendor,
1342                                    quirk->devid.subdevice);
1343
1344                 dev_data = pci_get_drvdata(quirk->pdev);
1345
1346                 list_for_each_entry(cfg_entry, &dev_data->config_fields, list) {
1347                         field = cfg_entry->field;
1348                         if (count >= PAGE_SIZE)
1349                                 goto out;
1350
1351                         count += scnprintf(buf + count, PAGE_SIZE - count,
1352                                            "\t\t%08x:%01x:%08x\n",
1353                                            cfg_entry->base_offset +
1354                                            field->offset, field->size,
1355                                            field->mask);
1356                 }
1357         }
1358
1359 out:
1360         spin_unlock_irqrestore(&device_ids_lock, flags);
1361
1362         return count;
1363 }
1364 static DRIVER_ATTR_RW(quirks);
1365
1366 static ssize_t permissive_store(struct device_driver *drv, const char *buf,
1367                                 size_t count)
1368 {
1369         int domain, bus, slot, func;
1370         int err;
1371         struct pcistub_device *psdev;
1372         struct xen_pcibk_dev_data *dev_data;
1373
1374         err = str_to_slot(buf, &domain, &bus, &slot, &func);
1375         if (err)
1376                 goto out;
1377
1378         psdev = pcistub_device_find(domain, bus, slot, func);
1379         if (!psdev) {
1380                 err = -ENODEV;
1381                 goto out;
1382         }
1383
1384         dev_data = pci_get_drvdata(psdev->dev);
1385         /* the driver data for a device should never be null at this point */
1386         if (!dev_data) {
1387                 err = -ENXIO;
1388                 goto release;
1389         }
1390         if (!dev_data->permissive) {
1391                 dev_data->permissive = 1;
1392                 /* Let user know that what they're doing could be unsafe */
1393                 dev_warn(&psdev->dev->dev, "enabling permissive mode "
1394                          "configuration space accesses!\n");
1395                 dev_warn(&psdev->dev->dev,
1396                          "permissive mode is potentially unsafe!\n");
1397         }
1398 release:
1399         pcistub_device_put(psdev);
1400 out:
1401         if (!err)
1402                 err = count;
1403         return err;
1404 }
1405
1406 static ssize_t permissive_show(struct device_driver *drv, char *buf)
1407 {
1408         struct pcistub_device *psdev;
1409         struct xen_pcibk_dev_data *dev_data;
1410         size_t count = 0;
1411         unsigned long flags;
1412         spin_lock_irqsave(&pcistub_devices_lock, flags);
1413         list_for_each_entry(psdev, &pcistub_devices, dev_list) {
1414                 if (count >= PAGE_SIZE)
1415                         break;
1416                 if (!psdev->dev)
1417                         continue;
1418                 dev_data = pci_get_drvdata(psdev->dev);
1419                 if (!dev_data || !dev_data->permissive)
1420                         continue;
1421                 count +=
1422                     scnprintf(buf + count, PAGE_SIZE - count, "%s\n",
1423                               pci_name(psdev->dev));
1424         }
1425         spin_unlock_irqrestore(&pcistub_devices_lock, flags);
1426         return count;
1427 }
1428 static DRIVER_ATTR_RW(permissive);
1429
1430 static ssize_t allow_interrupt_control_store(struct device_driver *drv,
1431                                              const char *buf, size_t count)
1432 {
1433         int domain, bus, slot, func;
1434         int err;
1435         struct pcistub_device *psdev;
1436         struct xen_pcibk_dev_data *dev_data;
1437
1438         err = str_to_slot(buf, &domain, &bus, &slot, &func);
1439         if (err)
1440                 goto out;
1441
1442         psdev = pcistub_device_find(domain, bus, slot, func);
1443         if (!psdev) {
1444                 err = -ENODEV;
1445                 goto out;
1446         }
1447
1448         dev_data = pci_get_drvdata(psdev->dev);
1449         /* the driver data for a device should never be null at this point */
1450         if (!dev_data) {
1451                 err = -ENXIO;
1452                 goto release;
1453         }
1454         dev_data->allow_interrupt_control = 1;
1455 release:
1456         pcistub_device_put(psdev);
1457 out:
1458         if (!err)
1459                 err = count;
1460         return err;
1461 }
1462
1463 static ssize_t allow_interrupt_control_show(struct device_driver *drv,
1464                                             char *buf)
1465 {
1466         struct pcistub_device *psdev;
1467         struct xen_pcibk_dev_data *dev_data;
1468         size_t count = 0;
1469         unsigned long flags;
1470
1471         spin_lock_irqsave(&pcistub_devices_lock, flags);
1472         list_for_each_entry(psdev, &pcistub_devices, dev_list) {
1473                 if (count >= PAGE_SIZE)
1474                         break;
1475                 if (!psdev->dev)
1476                         continue;
1477                 dev_data = pci_get_drvdata(psdev->dev);
1478                 if (!dev_data || !dev_data->allow_interrupt_control)
1479                         continue;
1480                 count +=
1481                     scnprintf(buf + count, PAGE_SIZE - count, "%s\n",
1482                               pci_name(psdev->dev));
1483         }
1484         spin_unlock_irqrestore(&pcistub_devices_lock, flags);
1485         return count;
1486 }
1487 static DRIVER_ATTR_RW(allow_interrupt_control);
1488
1489 static void pcistub_exit(void)
1490 {
1491         driver_remove_file(&xen_pcibk_pci_driver.driver, &driver_attr_new_slot);
1492         driver_remove_file(&xen_pcibk_pci_driver.driver,
1493                            &driver_attr_remove_slot);
1494         driver_remove_file(&xen_pcibk_pci_driver.driver, &driver_attr_slots);
1495         driver_remove_file(&xen_pcibk_pci_driver.driver, &driver_attr_quirks);
1496         driver_remove_file(&xen_pcibk_pci_driver.driver,
1497                            &driver_attr_permissive);
1498         driver_remove_file(&xen_pcibk_pci_driver.driver,
1499                            &driver_attr_allow_interrupt_control);
1500         driver_remove_file(&xen_pcibk_pci_driver.driver,
1501                            &driver_attr_irq_handlers);
1502         driver_remove_file(&xen_pcibk_pci_driver.driver,
1503                            &driver_attr_irq_handler_state);
1504         pci_unregister_driver(&xen_pcibk_pci_driver);
1505 }
1506
1507 static int __init pcistub_init(void)
1508 {
1509         int pos = 0;
1510         int err = 0;
1511         int domain, bus, slot, func;
1512         int parsed;
1513
1514         if (pci_devs_to_hide && *pci_devs_to_hide) {
1515                 do {
1516                         parsed = 0;
1517
1518                         err = sscanf(pci_devs_to_hide + pos,
1519                                      " (%x:%x:%x.%x) %n",
1520                                      &domain, &bus, &slot, &func, &parsed);
1521                         switch (err) {
1522                         case 3:
1523                                 func = -1;
1524                                 sscanf(pci_devs_to_hide + pos,
1525                                        " (%x:%x:%x.*) %n",
1526                                        &domain, &bus, &slot, &parsed);
1527                                 break;
1528                         case 2:
1529                                 slot = func = -1;
1530                                 sscanf(pci_devs_to_hide + pos,
1531                                        " (%x:%x:*.*) %n",
1532                                        &domain, &bus, &parsed);
1533                                 break;
1534                         }
1535
1536                         if (!parsed) {
1537                                 domain = 0;
1538                                 err = sscanf(pci_devs_to_hide + pos,
1539                                              " (%x:%x.%x) %n",
1540                                              &bus, &slot, &func, &parsed);
1541                                 switch (err) {
1542                                 case 2:
1543                                         func = -1;
1544                                         sscanf(pci_devs_to_hide + pos,
1545                                                " (%x:%x.*) %n",
1546                                                &bus, &slot, &parsed);
1547                                         break;
1548                                 case 1:
1549                                         slot = func = -1;
1550                                         sscanf(pci_devs_to_hide + pos,
1551                                                " (%x:*.*) %n",
1552                                                &bus, &parsed);
1553                                         break;
1554                                 }
1555                         }
1556
1557                         if (parsed <= 0)
1558                                 goto parse_error;
1559
1560                         err = pcistub_device_id_add(domain, bus, slot, func);
1561                         if (err)
1562                                 goto out;
1563
1564                         pos += parsed;
1565                 } while (pci_devs_to_hide[pos]);
1566         }
1567
1568         /* If we're the first PCI Device Driver to register, we're the
1569          * first one to get offered PCI devices as they become
1570          * available (and thus we can be the first to grab them)
1571          */
1572         err = pci_register_driver(&xen_pcibk_pci_driver);
1573         if (err < 0)
1574                 goto out;
1575
1576         err = driver_create_file(&xen_pcibk_pci_driver.driver,
1577                                  &driver_attr_new_slot);
1578         if (!err)
1579                 err = driver_create_file(&xen_pcibk_pci_driver.driver,
1580                                          &driver_attr_remove_slot);
1581         if (!err)
1582                 err = driver_create_file(&xen_pcibk_pci_driver.driver,
1583                                          &driver_attr_slots);
1584         if (!err)
1585                 err = driver_create_file(&xen_pcibk_pci_driver.driver,
1586                                          &driver_attr_quirks);
1587         if (!err)
1588                 err = driver_create_file(&xen_pcibk_pci_driver.driver,
1589                                          &driver_attr_permissive);
1590         if (!err)
1591                 err = driver_create_file(&xen_pcibk_pci_driver.driver,
1592                                          &driver_attr_allow_interrupt_control);
1593
1594         if (!err)
1595                 err = driver_create_file(&xen_pcibk_pci_driver.driver,
1596                                          &driver_attr_irq_handlers);
1597         if (!err)
1598                 err = driver_create_file(&xen_pcibk_pci_driver.driver,
1599                                         &driver_attr_irq_handler_state);
1600         if (err)
1601                 pcistub_exit();
1602
1603 out:
1604         return err;
1605
1606 parse_error:
1607         pr_err("Error parsing pci_devs_to_hide at \"%s\"\n",
1608                pci_devs_to_hide + pos);
1609         return -EINVAL;
1610 }
1611
1612 #ifndef MODULE
1613 /*
1614  * fs_initcall happens before device_initcall
1615  * so xen_pcibk *should* get called first (b/c we
1616  * want to suck up any device before other drivers
1617  * get a chance by being the first pci device
1618  * driver to register)
1619  */
1620 fs_initcall(pcistub_init);
1621 #endif
1622
1623 #ifdef CONFIG_PCI_IOV
1624 static struct pcistub_device *find_vfs(const struct pci_dev *pdev)
1625 {
1626         struct pcistub_device *psdev = NULL;
1627         unsigned long flags;
1628         bool found = false;
1629
1630         spin_lock_irqsave(&pcistub_devices_lock, flags);
1631         list_for_each_entry(psdev, &pcistub_devices, dev_list) {
1632                 if (!psdev->pdev && psdev->dev != pdev
1633                     && pci_physfn(psdev->dev) == pdev) {
1634                         found = true;
1635                         break;
1636                 }
1637         }
1638         spin_unlock_irqrestore(&pcistub_devices_lock, flags);
1639         if (found)
1640                 return psdev;
1641         return NULL;
1642 }
1643
1644 static int pci_stub_notifier(struct notifier_block *nb,
1645                              unsigned long action, void *data)
1646 {
1647         struct device *dev = data;
1648         const struct pci_dev *pdev = to_pci_dev(dev);
1649
1650         if (action != BUS_NOTIFY_UNBIND_DRIVER)
1651                 return NOTIFY_DONE;
1652
1653         if (!pdev->is_physfn)
1654                 return NOTIFY_DONE;
1655
1656         for (;;) {
1657                 struct pcistub_device *psdev = find_vfs(pdev);
1658                 if (!psdev)
1659                         break;
1660                 device_release_driver(&psdev->dev->dev);
1661         }
1662         return NOTIFY_DONE;
1663 }
1664
1665 static struct notifier_block pci_stub_nb = {
1666         .notifier_call = pci_stub_notifier,
1667 };
1668 #endif
1669
1670 static int __init xen_pcibk_init(void)
1671 {
1672         int err;
1673
1674         if (!xen_initial_domain())
1675                 return -ENODEV;
1676
1677         err = xen_pcibk_config_init();
1678         if (err)
1679                 return err;
1680
1681 #ifdef MODULE
1682         err = pcistub_init();
1683         if (err < 0)
1684                 return err;
1685 #endif
1686
1687         pcistub_init_devices_late();
1688         err = xen_pcibk_xenbus_register();
1689         if (err)
1690                 pcistub_exit();
1691 #ifdef CONFIG_PCI_IOV
1692         else
1693                 bus_register_notifier(&pci_bus_type, &pci_stub_nb);
1694 #endif
1695
1696         return err;
1697 }
1698
1699 static void __exit xen_pcibk_cleanup(void)
1700 {
1701 #ifdef CONFIG_PCI_IOV
1702         bus_unregister_notifier(&pci_bus_type, &pci_stub_nb);
1703 #endif
1704         xen_pcibk_xenbus_unregister();
1705         pcistub_exit();
1706 }
1707
1708 module_init(xen_pcibk_init);
1709 module_exit(xen_pcibk_cleanup);
1710
1711 MODULE_LICENSE("Dual BSD/GPL");
1712 MODULE_ALIAS("xen-backend:pci");