linux/drivers/xen/xen-pciback/pci_stub.c
<<
>>
Prefs
   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 <asm/xen/pci.h>
  23#include <asm/xen/hypervisor.h>
  24#include <xen/interface/physdev.h>
  25#include "pciback.h"
  26#include "conf_space.h"
  27#include "conf_space_quirks.h"
  28
  29#define PCISTUB_DRIVER_NAME "pciback"
  30
  31static char *pci_devs_to_hide;
  32wait_queue_head_t xen_pcibk_aer_wait_queue;
  33/*Add sem for sync AER handling and xen_pcibk remove/reconfigue ops,
  34* We want to avoid in middle of AER ops, xen_pcibk devices is being removed
  35*/
  36static DECLARE_RWSEM(pcistub_sem);
  37module_param_named(hide, pci_devs_to_hide, charp, 0444);
  38
  39struct pcistub_device_id {
  40        struct list_head slot_list;
  41        int domain;
  42        unsigned char bus;
  43        unsigned int devfn;
  44};
  45static LIST_HEAD(pcistub_device_ids);
  46static DEFINE_SPINLOCK(device_ids_lock);
  47
  48struct pcistub_device {
  49        struct kref kref;
  50        struct list_head dev_list;
  51        spinlock_t lock;
  52
  53        struct pci_dev *dev;
  54        struct xen_pcibk_device *pdev;/* non-NULL if struct pci_dev is in use */
  55};
  56
  57/* Access to pcistub_devices & seized_devices lists and the initialize_devices
  58 * flag must be locked with pcistub_devices_lock
  59 */
  60static DEFINE_SPINLOCK(pcistub_devices_lock);
  61static LIST_HEAD(pcistub_devices);
  62
  63/* wait for device_initcall before initializing our devices
  64 * (see pcistub_init_devices_late)
  65 */
  66static int initialize_devices;
  67static LIST_HEAD(seized_devices);
  68
  69static struct pcistub_device *pcistub_device_alloc(struct pci_dev *dev)
  70{
  71        struct pcistub_device *psdev;
  72
  73        dev_dbg(&dev->dev, "pcistub_device_alloc\n");
  74
  75        psdev = kzalloc(sizeof(*psdev), GFP_KERNEL);
  76        if (!psdev)
  77                return NULL;
  78
  79        psdev->dev = pci_dev_get(dev);
  80        if (!psdev->dev) {
  81                kfree(psdev);
  82                return NULL;
  83        }
  84
  85        kref_init(&psdev->kref);
  86        spin_lock_init(&psdev->lock);
  87
  88        return psdev;
  89}
  90
  91/* Don't call this directly as it's called by pcistub_device_put */
  92static void pcistub_device_release(struct kref *kref)
  93{
  94        struct pcistub_device *psdev;
  95        struct pci_dev *dev;
  96        struct xen_pcibk_dev_data *dev_data;
  97
  98        psdev = container_of(kref, struct pcistub_device, kref);
  99        dev = psdev->dev;
 100        dev_data = pci_get_drvdata(dev);
 101
 102        dev_dbg(&dev->dev, "pcistub_device_release\n");
 103
 104        xen_unregister_device_domain_owner(dev);
 105
 106        /* Call the reset function which does not take lock as this
 107         * is called from "unbind" which takes a device_lock mutex.
 108         */
 109        __pci_reset_function_locked(dev);
 110        if (dev_data &&
 111            pci_load_and_free_saved_state(dev, &dev_data->pci_saved_state))
 112                dev_info(&dev->dev, "Could not reload PCI state\n");
 113        else
 114                pci_restore_state(dev);
 115
 116        if (dev->msix_cap) {
 117                struct physdev_pci_device ppdev = {
 118                        .seg = pci_domain_nr(dev->bus),
 119                        .bus = dev->bus->number,
 120                        .devfn = dev->devfn
 121                };
 122                int err = HYPERVISOR_physdev_op(PHYSDEVOP_release_msix,
 123                                                &ppdev);
 124
 125                if (err && err != -ENOSYS)
 126                        dev_warn(&dev->dev, "MSI-X release failed (%d)\n",
 127                                 err);
 128        }
 129
 130        /* Disable the device */
 131        xen_pcibk_reset_device(dev);
 132
 133        kfree(dev_data);
 134        pci_set_drvdata(dev, NULL);
 135
 136        /* Clean-up the device */
 137        xen_pcibk_config_free_dyn_fields(dev);
 138        xen_pcibk_config_free_dev(dev);
 139
 140        pci_clear_dev_assigned(dev);
 141        pci_dev_put(dev);
 142
 143        kfree(psdev);
 144}
 145
 146static inline void pcistub_device_get(struct pcistub_device *psdev)
 147{
 148        kref_get(&psdev->kref);
 149}
 150
 151static inline void pcistub_device_put(struct pcistub_device *psdev)
 152{
 153        kref_put(&psdev->kref, pcistub_device_release);
 154}
 155
 156static struct pcistub_device *pcistub_device_find_locked(int domain, int bus,
 157                                                         int slot, int func)
 158{
 159        struct pcistub_device *psdev;
 160
 161        list_for_each_entry(psdev, &pcistub_devices, dev_list) {
 162                if (psdev->dev != NULL
 163                    && domain == pci_domain_nr(psdev->dev->bus)
 164                    && bus == psdev->dev->bus->number
 165                    && slot == PCI_SLOT(psdev->dev->devfn)
 166                    && func == PCI_FUNC(psdev->dev->devfn)) {
 167                        return psdev;
 168                }
 169        }
 170
 171        return NULL;
 172}
 173
 174static struct pcistub_device *pcistub_device_find(int domain, int bus,
 175                                                  int slot, int func)
 176{
 177        struct pcistub_device *psdev;
 178        unsigned long flags;
 179
 180        spin_lock_irqsave(&pcistub_devices_lock, flags);
 181
 182        psdev = pcistub_device_find_locked(domain, bus, slot, func);
 183        if (psdev)
 184                pcistub_device_get(psdev);
 185
 186        spin_unlock_irqrestore(&pcistub_devices_lock, flags);
 187        return psdev;
 188}
 189
 190static struct pci_dev *pcistub_device_get_pci_dev(struct xen_pcibk_device *pdev,
 191                                                  struct pcistub_device *psdev)
 192{
 193        struct pci_dev *pci_dev = NULL;
 194        unsigned long flags;
 195
 196        pcistub_device_get(psdev);
 197
 198        spin_lock_irqsave(&psdev->lock, flags);
 199        if (!psdev->pdev) {
 200                psdev->pdev = pdev;
 201                pci_dev = psdev->dev;
 202        }
 203        spin_unlock_irqrestore(&psdev->lock, flags);
 204
 205        if (!pci_dev)
 206                pcistub_device_put(psdev);
 207
 208        return pci_dev;
 209}
 210
 211struct pci_dev *pcistub_get_pci_dev_by_slot(struct xen_pcibk_device *pdev,
 212                                            int domain, int bus,
 213                                            int slot, int func)
 214{
 215        struct pcistub_device *psdev;
 216        struct pci_dev *found_dev = NULL;
 217        unsigned long flags;
 218
 219        spin_lock_irqsave(&pcistub_devices_lock, flags);
 220
 221        psdev = pcistub_device_find_locked(domain, bus, slot, func);
 222        if (psdev)
 223                found_dev = pcistub_device_get_pci_dev(pdev, psdev);
 224
 225        spin_unlock_irqrestore(&pcistub_devices_lock, flags);
 226        return found_dev;
 227}
 228
 229struct pci_dev *pcistub_get_pci_dev(struct xen_pcibk_device *pdev,
 230                                    struct pci_dev *dev)
 231{
 232        struct pcistub_device *psdev;
 233        struct pci_dev *found_dev = NULL;
 234        unsigned long flags;
 235
 236        spin_lock_irqsave(&pcistub_devices_lock, flags);
 237
 238        list_for_each_entry(psdev, &pcistub_devices, dev_list) {
 239                if (psdev->dev == dev) {
 240                        found_dev = pcistub_device_get_pci_dev(pdev, psdev);
 241                        break;
 242                }
 243        }
 244
 245        spin_unlock_irqrestore(&pcistub_devices_lock, flags);
 246        return found_dev;
 247}
 248
 249/*
 250 * Called when:
 251 *  - XenBus state has been reconfigure (pci unplug). See xen_pcibk_remove_device
 252 *  - XenBus state has been disconnected (guest shutdown). See xen_pcibk_xenbus_remove
 253 *  - 'echo BDF > unbind' on pciback module with no guest attached. See pcistub_remove
 254 *  - 'echo BDF > unbind' with a guest still using it. See pcistub_remove
 255 *
 256 *  As such we have to be careful.
 257 *
 258 *  To make this easier, the caller has to hold the device lock.
 259 */
 260void pcistub_put_pci_dev(struct pci_dev *dev)
 261{
 262        struct pcistub_device *psdev, *found_psdev = NULL;
 263        unsigned long flags;
 264        struct xen_pcibk_dev_data *dev_data;
 265        int ret;
 266
 267        spin_lock_irqsave(&pcistub_devices_lock, flags);
 268
 269        list_for_each_entry(psdev, &pcistub_devices, dev_list) {
 270                if (psdev->dev == dev) {
 271                        found_psdev = psdev;
 272                        break;
 273                }
 274        }
 275
 276        spin_unlock_irqrestore(&pcistub_devices_lock, flags);
 277        if (WARN_ON(!found_psdev))
 278                return;
 279
 280        /*hold this lock for avoiding breaking link between
 281        * pcistub and xen_pcibk when AER is in processing
 282        */
 283        down_write(&pcistub_sem);
 284        /* Cleanup our device
 285         * (so it's ready for the next domain)
 286         */
 287        device_lock_assert(&dev->dev);
 288        __pci_reset_function_locked(dev);
 289
 290        dev_data = pci_get_drvdata(dev);
 291        ret = pci_load_saved_state(dev, dev_data->pci_saved_state);
 292        if (!ret) {
 293                /*
 294                 * The usual sequence is pci_save_state & pci_restore_state
 295                 * but the guest might have messed the configuration space up.
 296                 * Use the initial version (when device was bound to us).
 297                 */
 298                pci_restore_state(dev);
 299        } else
 300                dev_info(&dev->dev, "Could not reload PCI state\n");
 301        /* This disables the device. */
 302        xen_pcibk_reset_device(dev);
 303
 304        /* And cleanup up our emulated fields. */
 305        xen_pcibk_config_reset_dev(dev);
 306        xen_pcibk_config_free_dyn_fields(dev);
 307
 308        dev_data->allow_interrupt_control = 0;
 309
 310        xen_unregister_device_domain_owner(dev);
 311
 312        spin_lock_irqsave(&found_psdev->lock, flags);
 313        found_psdev->pdev = NULL;
 314        spin_unlock_irqrestore(&found_psdev->lock, flags);
 315
 316        pcistub_device_put(found_psdev);
 317        up_write(&pcistub_sem);
 318}
 319
 320static int pcistub_match_one(struct pci_dev *dev,
 321                             struct pcistub_device_id *pdev_id)
 322{
 323        /* Match the specified device by domain, bus, slot, func and also if
 324         * any of the device's parent bridges match.
 325         */
 326        for (; dev != NULL; dev = dev->bus->self) {
 327                if (pci_domain_nr(dev->bus) == pdev_id->domain
 328                    && dev->bus->number == pdev_id->bus
 329                    && dev->devfn == pdev_id->devfn)
 330                        return 1;
 331
 332                /* Sometimes topmost bridge links to itself. */
 333                if (dev == dev->bus->self)
 334                        break;
 335        }
 336
 337        return 0;
 338}
 339
 340static int pcistub_match(struct pci_dev *dev)
 341{
 342        struct pcistub_device_id *pdev_id;
 343        unsigned long flags;
 344        int found = 0;
 345
 346        spin_lock_irqsave(&device_ids_lock, flags);
 347        list_for_each_entry(pdev_id, &pcistub_device_ids, slot_list) {
 348                if (pcistub_match_one(dev, pdev_id)) {
 349                        found = 1;
 350                        break;
 351                }
 352        }
 353        spin_unlock_irqrestore(&device_ids_lock, flags);
 354
 355        return found;
 356}
 357
 358static int pcistub_init_device(struct pci_dev *dev)
 359{
 360        struct xen_pcibk_dev_data *dev_data;
 361        int err = 0;
 362
 363        dev_dbg(&dev->dev, "initializing...\n");
 364
 365        /* The PCI backend is not intended to be a module (or to work with
 366         * removable PCI devices (yet). If it were, xen_pcibk_config_free()
 367         * would need to be called somewhere to free the memory allocated
 368         * here and then to call kfree(pci_get_drvdata(psdev->dev)).
 369         */
 370        dev_data = kzalloc(sizeof(*dev_data) +  strlen(DRV_NAME "[]")
 371                                + strlen(pci_name(dev)) + 1, GFP_KERNEL);
 372        if (!dev_data) {
 373                err = -ENOMEM;
 374                goto out;
 375        }
 376        pci_set_drvdata(dev, dev_data);
 377
 378        /*
 379         * Setup name for fake IRQ handler. It will only be enabled
 380         * once the device is turned on by the guest.
 381         */
 382        sprintf(dev_data->irq_name, DRV_NAME "[%s]", pci_name(dev));
 383
 384        dev_dbg(&dev->dev, "initializing config\n");
 385
 386        init_waitqueue_head(&xen_pcibk_aer_wait_queue);
 387        err = xen_pcibk_config_init_dev(dev);
 388        if (err)
 389                goto out;
 390
 391        /* HACK: Force device (& ACPI) to determine what IRQ it's on - we
 392         * must do this here because pcibios_enable_device may specify
 393         * the pci device's true irq (and possibly its other resources)
 394         * if they differ from what's in the configuration space.
 395         * This makes the assumption that the device's resources won't
 396         * change after this point (otherwise this code may break!)
 397         */
 398        dev_dbg(&dev->dev, "enabling device\n");
 399        err = pci_enable_device(dev);
 400        if (err)
 401                goto config_release;
 402
 403        if (dev->msix_cap) {
 404                struct physdev_pci_device ppdev = {
 405                        .seg = pci_domain_nr(dev->bus),
 406                        .bus = dev->bus->number,
 407                        .devfn = dev->devfn
 408                };
 409
 410                err = HYPERVISOR_physdev_op(PHYSDEVOP_prepare_msix, &ppdev);
 411                if (err && err != -ENOSYS)
 412                        dev_err(&dev->dev, "MSI-X preparation failed (%d)\n",
 413                                err);
 414        }
 415
 416        /* We need the device active to save the state. */
 417        dev_dbg(&dev->dev, "save state of device\n");
 418        pci_save_state(dev);
 419        dev_data->pci_saved_state = pci_store_saved_state(dev);
 420        if (!dev_data->pci_saved_state)
 421                dev_err(&dev->dev, "Could not store PCI conf saved state!\n");
 422        else {
 423                dev_dbg(&dev->dev, "resetting (FLR, D3, etc) the device\n");
 424                __pci_reset_function_locked(dev);
 425                pci_restore_state(dev);
 426        }
 427        /* Now disable the device (this also ensures some private device
 428         * data is setup before we export)
 429         */
 430        dev_dbg(&dev->dev, "reset device\n");
 431        xen_pcibk_reset_device(dev);
 432
 433        pci_set_dev_assigned(dev);
 434        return 0;
 435
 436config_release:
 437        xen_pcibk_config_free_dev(dev);
 438
 439out:
 440        pci_set_drvdata(dev, NULL);
 441        kfree(dev_data);
 442        return err;
 443}
 444
 445/*
 446 * Because some initialization still happens on
 447 * devices during fs_initcall, we need to defer
 448 * full initialization of our devices until
 449 * device_initcall.
 450 */
 451static int __init pcistub_init_devices_late(void)
 452{
 453        struct pcistub_device *psdev;
 454        unsigned long flags;
 455        int err = 0;
 456
 457        spin_lock_irqsave(&pcistub_devices_lock, flags);
 458
 459        while (!list_empty(&seized_devices)) {
 460                psdev = container_of(seized_devices.next,
 461                                     struct pcistub_device, dev_list);
 462                list_del(&psdev->dev_list);
 463
 464                spin_unlock_irqrestore(&pcistub_devices_lock, flags);
 465
 466                err = pcistub_init_device(psdev->dev);
 467                if (err) {
 468                        dev_err(&psdev->dev->dev,
 469                                "error %d initializing device\n", err);
 470                        kfree(psdev);
 471                        psdev = NULL;
 472                }
 473
 474                spin_lock_irqsave(&pcistub_devices_lock, flags);
 475
 476                if (psdev)
 477                        list_add_tail(&psdev->dev_list, &pcistub_devices);
 478        }
 479
 480        initialize_devices = 1;
 481
 482        spin_unlock_irqrestore(&pcistub_devices_lock, flags);
 483
 484        return 0;
 485}
 486
 487static void pcistub_device_id_add_list(struct pcistub_device_id *new,
 488                                       int domain, int bus, unsigned int devfn)
 489{
 490        struct pcistub_device_id *pci_dev_id;
 491        unsigned long flags;
 492        int found = 0;
 493
 494        spin_lock_irqsave(&device_ids_lock, flags);
 495
 496        list_for_each_entry(pci_dev_id, &pcistub_device_ids, slot_list) {
 497                if (pci_dev_id->domain == domain && pci_dev_id->bus == bus &&
 498                    pci_dev_id->devfn == devfn) {
 499                        found = 1;
 500                        break;
 501                }
 502        }
 503
 504        if (!found) {
 505                new->domain = domain;
 506                new->bus = bus;
 507                new->devfn = devfn;
 508                list_add_tail(&new->slot_list, &pcistub_device_ids);
 509        }
 510
 511        spin_unlock_irqrestore(&device_ids_lock, flags);
 512
 513        if (found)
 514                kfree(new);
 515}
 516
 517static int pcistub_seize(struct pci_dev *dev,
 518                         struct pcistub_device_id *pci_dev_id)
 519{
 520        struct pcistub_device *psdev;
 521        unsigned long flags;
 522        int err = 0;
 523
 524        psdev = pcistub_device_alloc(dev);
 525        if (!psdev) {
 526                kfree(pci_dev_id);
 527                return -ENOMEM;
 528        }
 529
 530        spin_lock_irqsave(&pcistub_devices_lock, flags);
 531
 532        if (initialize_devices) {
 533                spin_unlock_irqrestore(&pcistub_devices_lock, flags);
 534
 535                /* don't want irqs disabled when calling pcistub_init_device */
 536                err = pcistub_init_device(psdev->dev);
 537
 538                spin_lock_irqsave(&pcistub_devices_lock, flags);
 539
 540                if (!err)
 541                        list_add(&psdev->dev_list, &pcistub_devices);
 542        } else {
 543                dev_dbg(&dev->dev, "deferring initialization\n");
 544                list_add(&psdev->dev_list, &seized_devices);
 545        }
 546
 547        spin_unlock_irqrestore(&pcistub_devices_lock, flags);
 548
 549        if (err) {
 550                kfree(pci_dev_id);
 551                pcistub_device_put(psdev);
 552        } else if (pci_dev_id)
 553                pcistub_device_id_add_list(pci_dev_id, pci_domain_nr(dev->bus),
 554                                           dev->bus->number, dev->devfn);
 555
 556        return err;
 557}
 558
 559/* Called when 'bind'. This means we must _NOT_ call pci_reset_function or
 560 * other functions that take the sysfs lock. */
 561static int pcistub_probe(struct pci_dev *dev, const struct pci_device_id *id)
 562{
 563        int err = 0, match;
 564        struct pcistub_device_id *pci_dev_id = NULL;
 565
 566        dev_dbg(&dev->dev, "probing...\n");
 567
 568        match = pcistub_match(dev);
 569
 570        if ((dev->driver_override &&
 571             !strcmp(dev->driver_override, PCISTUB_DRIVER_NAME)) ||
 572            match) {
 573
 574                if (dev->hdr_type != PCI_HEADER_TYPE_NORMAL
 575                    && dev->hdr_type != PCI_HEADER_TYPE_BRIDGE) {
 576                        dev_err(&dev->dev, "can't export pci devices that "
 577                                "don't have a normal (0) or bridge (1) "
 578                                "header type!\n");
 579                        err = -ENODEV;
 580                        goto out;
 581                }
 582
 583                if (!match) {
 584                        pci_dev_id = kmalloc(sizeof(*pci_dev_id), GFP_KERNEL);
 585                        if (!pci_dev_id) {
 586                                err = -ENOMEM;
 587                                goto out;
 588                        }
 589                }
 590
 591                dev_info(&dev->dev, "seizing device\n");
 592                err = pcistub_seize(dev, pci_dev_id);
 593        } else
 594                /* Didn't find the device */
 595                err = -ENODEV;
 596
 597out:
 598        return err;
 599}
 600
 601/* Called when 'unbind'. This means we must _NOT_ call pci_reset_function or
 602 * other functions that take the sysfs lock. */
 603static void pcistub_remove(struct pci_dev *dev)
 604{
 605        struct pcistub_device *psdev, *found_psdev = NULL;
 606        unsigned long flags;
 607
 608        dev_dbg(&dev->dev, "removing\n");
 609
 610        spin_lock_irqsave(&pcistub_devices_lock, flags);
 611
 612        xen_pcibk_config_quirk_release(dev);
 613
 614        list_for_each_entry(psdev, &pcistub_devices, dev_list) {
 615                if (psdev->dev == dev) {
 616                        found_psdev = psdev;
 617                        break;
 618                }
 619        }
 620
 621        spin_unlock_irqrestore(&pcistub_devices_lock, flags);
 622
 623        if (found_psdev) {
 624                dev_dbg(&dev->dev, "found device to remove %s\n",
 625                        found_psdev->pdev ? "- in-use" : "");
 626
 627                if (found_psdev->pdev) {
 628                        int domid = xen_find_device_domain_owner(dev);
 629
 630                        dev_warn(&dev->dev, "****** removing device %s while still in-use by domain %d! ******\n",
 631                               pci_name(found_psdev->dev), domid);
 632                        dev_warn(&dev->dev, "****** driver domain may still access this device's i/o resources!\n");
 633                        dev_warn(&dev->dev, "****** shutdown driver domain before binding device\n");
 634                        dev_warn(&dev->dev, "****** to other drivers or domains\n");
 635
 636                        /* N.B. This ends up calling pcistub_put_pci_dev which ends up
 637                         * doing the FLR. */
 638                        xen_pcibk_release_pci_dev(found_psdev->pdev,
 639                                                found_psdev->dev,
 640                                                false /* caller holds the lock. */);
 641                }
 642
 643                spin_lock_irqsave(&pcistub_devices_lock, flags);
 644                list_del(&found_psdev->dev_list);
 645                spin_unlock_irqrestore(&pcistub_devices_lock, flags);
 646
 647                /* the final put for releasing from the list */
 648                pcistub_device_put(found_psdev);
 649        }
 650}
 651
 652static const struct pci_device_id pcistub_ids[] = {
 653        {
 654         .vendor = PCI_ANY_ID,
 655         .device = PCI_ANY_ID,
 656         .subvendor = PCI_ANY_ID,
 657         .subdevice = PCI_ANY_ID,
 658         },
 659        {0,},
 660};
 661
 662#define PCI_NODENAME_MAX 40
 663static void kill_domain_by_device(struct pcistub_device *psdev)
 664{
 665        struct xenbus_transaction xbt;
 666        int err;
 667        char nodename[PCI_NODENAME_MAX];
 668
 669        BUG_ON(!psdev);
 670        snprintf(nodename, PCI_NODENAME_MAX, "/local/domain/0/backend/pci/%d/0",
 671                psdev->pdev->xdev->otherend_id);
 672
 673again:
 674        err = xenbus_transaction_start(&xbt);
 675        if (err) {
 676                dev_err(&psdev->dev->dev,
 677                        "error %d when start xenbus transaction\n", err);
 678                return;
 679        }
 680        /*PV AER handlers will set this flag*/
 681        xenbus_printf(xbt, nodename, "aerState" , "aerfail");
 682        err = xenbus_transaction_end(xbt, 0);
 683        if (err) {
 684                if (err == -EAGAIN)
 685                        goto again;
 686                dev_err(&psdev->dev->dev,
 687                        "error %d when end xenbus transaction\n", err);
 688                return;
 689        }
 690}
 691
 692/* For each aer recovery step error_detected, mmio_enabled, etc, front_end and
 693 * backend need to have cooperation. In xen_pcibk, those steps will do similar
 694 * jobs: send service request and waiting for front_end response.
 695*/
 696static pci_ers_result_t common_process(struct pcistub_device *psdev,
 697                                       pci_channel_state_t state, int aer_cmd,
 698                                       pci_ers_result_t result)
 699{
 700        pci_ers_result_t res = result;
 701        struct xen_pcie_aer_op *aer_op;
 702        struct xen_pcibk_device *pdev = psdev->pdev;
 703        struct xen_pci_sharedinfo *sh_info = pdev->sh_info;
 704        int ret;
 705
 706        /*with PV AER drivers*/
 707        aer_op = &(sh_info->aer_op);
 708        aer_op->cmd = aer_cmd ;
 709        /*useful for error_detected callback*/
 710        aer_op->err = state;
 711        /*pcifront_end BDF*/
 712        ret = xen_pcibk_get_pcifront_dev(psdev->dev, psdev->pdev,
 713                &aer_op->domain, &aer_op->bus, &aer_op->devfn);
 714        if (!ret) {
 715                dev_err(&psdev->dev->dev, "failed to get pcifront device\n");
 716                return PCI_ERS_RESULT_NONE;
 717        }
 718        wmb();
 719
 720        dev_dbg(&psdev->dev->dev, "aer_op %x dom %x bus %x devfn %x\n",
 721                        aer_cmd, aer_op->domain, aer_op->bus, aer_op->devfn);
 722        /*local flag to mark there's aer request, xen_pcibk callback will use
 723        * this flag to judge whether we need to check pci-front give aer
 724        * service ack signal
 725        */
 726        set_bit(_PCIB_op_pending, (unsigned long *)&pdev->flags);
 727
 728        /*It is possible that a pcifront conf_read_write ops request invokes
 729        * the callback which cause the spurious execution of wake_up.
 730        * Yet it is harmless and better than a spinlock here
 731        */
 732        set_bit(_XEN_PCIB_active,
 733                (unsigned long *)&sh_info->flags);
 734        wmb();
 735        notify_remote_via_irq(pdev->evtchn_irq);
 736
 737        /* Enable IRQ to signal "request done". */
 738        xen_pcibk_lateeoi(pdev, 0);
 739
 740        ret = wait_event_timeout(xen_pcibk_aer_wait_queue,
 741                                 !(test_bit(_XEN_PCIB_active, (unsigned long *)
 742                                 &sh_info->flags)), 300*HZ);
 743
 744        /* Enable IRQ for pcifront request if not already active. */
 745        if (!test_bit(_PDEVF_op_active, &pdev->flags))
 746                xen_pcibk_lateeoi(pdev, 0);
 747
 748        if (!ret) {
 749                if (test_bit(_XEN_PCIB_active,
 750                        (unsigned long *)&sh_info->flags)) {
 751                        dev_err(&psdev->dev->dev,
 752                                "pcifront aer process not responding!\n");
 753                        clear_bit(_XEN_PCIB_active,
 754                          (unsigned long *)&sh_info->flags);
 755                        aer_op->err = PCI_ERS_RESULT_NONE;
 756                        return res;
 757                }
 758        }
 759        clear_bit(_PCIB_op_pending, (unsigned long *)&pdev->flags);
 760
 761        res = (pci_ers_result_t)aer_op->err;
 762        return res;
 763}
 764
 765/*
 766* xen_pcibk_slot_reset: it will send the slot_reset request to  pcifront in case
 767* of the device driver could provide this service, and then wait for pcifront
 768* ack.
 769* @dev: pointer to PCI devices
 770* return value is used by aer_core do_recovery policy
 771*/
 772static pci_ers_result_t xen_pcibk_slot_reset(struct pci_dev *dev)
 773{
 774        struct pcistub_device *psdev;
 775        pci_ers_result_t result;
 776
 777        result = PCI_ERS_RESULT_RECOVERED;
 778        dev_dbg(&dev->dev, "xen_pcibk_slot_reset(bus:%x,devfn:%x)\n",
 779                dev->bus->number, dev->devfn);
 780
 781        down_write(&pcistub_sem);
 782        psdev = pcistub_device_find(pci_domain_nr(dev->bus),
 783                                dev->bus->number,
 784                                PCI_SLOT(dev->devfn),
 785                                PCI_FUNC(dev->devfn));
 786
 787        if (!psdev || !psdev->pdev) {
 788                dev_err(&dev->dev, "device is not found/assigned\n");
 789                goto end;
 790        }
 791
 792        if (!psdev->pdev->sh_info) {
 793                dev_err(&dev->dev, "device is not connected or owned"
 794                        " by HVM, kill it\n");
 795                kill_domain_by_device(psdev);
 796                goto end;
 797        }
 798
 799        if (!test_bit(_XEN_PCIB_AERHANDLER,
 800                (unsigned long *)&psdev->pdev->sh_info->flags)) {
 801                dev_err(&dev->dev,
 802                        "guest with no AER driver should have been killed\n");
 803                goto end;
 804        }
 805        result = common_process(psdev, pci_channel_io_normal, XEN_PCI_OP_aer_slotreset, result);
 806
 807        if (result == PCI_ERS_RESULT_NONE ||
 808                result == PCI_ERS_RESULT_DISCONNECT) {
 809                dev_dbg(&dev->dev,
 810                        "No AER slot_reset service or disconnected!\n");
 811                kill_domain_by_device(psdev);
 812        }
 813end:
 814        if (psdev)
 815                pcistub_device_put(psdev);
 816        up_write(&pcistub_sem);
 817        return result;
 818
 819}
 820
 821
 822/*xen_pcibk_mmio_enabled: it will send the mmio_enabled request to  pcifront
 823* in case of the device driver could provide this service, and then wait
 824* for pcifront ack
 825* @dev: pointer to PCI devices
 826* return value is used by aer_core do_recovery policy
 827*/
 828
 829static pci_ers_result_t xen_pcibk_mmio_enabled(struct pci_dev *dev)
 830{
 831        struct pcistub_device *psdev;
 832        pci_ers_result_t result;
 833
 834        result = PCI_ERS_RESULT_RECOVERED;
 835        dev_dbg(&dev->dev, "xen_pcibk_mmio_enabled(bus:%x,devfn:%x)\n",
 836                dev->bus->number, dev->devfn);
 837
 838        down_write(&pcistub_sem);
 839        psdev = pcistub_device_find(pci_domain_nr(dev->bus),
 840                                dev->bus->number,
 841                                PCI_SLOT(dev->devfn),
 842                                PCI_FUNC(dev->devfn));
 843
 844        if (!psdev || !psdev->pdev) {
 845                dev_err(&dev->dev, "device is not found/assigned\n");
 846                goto end;
 847        }
 848
 849        if (!psdev->pdev->sh_info) {
 850                dev_err(&dev->dev, "device is not connected or owned"
 851                        " by HVM, kill it\n");
 852                kill_domain_by_device(psdev);
 853                goto end;
 854        }
 855
 856        if (!test_bit(_XEN_PCIB_AERHANDLER,
 857                (unsigned long *)&psdev->pdev->sh_info->flags)) {
 858                dev_err(&dev->dev,
 859                        "guest with no AER driver should have been killed\n");
 860                goto end;
 861        }
 862        result = common_process(psdev, pci_channel_io_normal, XEN_PCI_OP_aer_mmio, result);
 863
 864        if (result == PCI_ERS_RESULT_NONE ||
 865                result == PCI_ERS_RESULT_DISCONNECT) {
 866                dev_dbg(&dev->dev,
 867                        "No AER mmio_enabled service or disconnected!\n");
 868                kill_domain_by_device(psdev);
 869        }
 870end:
 871        if (psdev)
 872                pcistub_device_put(psdev);
 873        up_write(&pcistub_sem);
 874        return result;
 875}
 876
 877/*xen_pcibk_error_detected: it will send the error_detected request to  pcifront
 878* in case of the device driver could provide this service, and then wait
 879* for pcifront ack.
 880* @dev: pointer to PCI devices
 881* @error: the current PCI connection state
 882* return value is used by aer_core do_recovery policy
 883*/
 884
 885static pci_ers_result_t xen_pcibk_error_detected(struct pci_dev *dev,
 886        pci_channel_state_t error)
 887{
 888        struct pcistub_device *psdev;
 889        pci_ers_result_t result;
 890
 891        result = PCI_ERS_RESULT_CAN_RECOVER;
 892        dev_dbg(&dev->dev, "xen_pcibk_error_detected(bus:%x,devfn:%x)\n",
 893                dev->bus->number, dev->devfn);
 894
 895        down_write(&pcistub_sem);
 896        psdev = pcistub_device_find(pci_domain_nr(dev->bus),
 897                                dev->bus->number,
 898                                PCI_SLOT(dev->devfn),
 899                                PCI_FUNC(dev->devfn));
 900
 901        if (!psdev || !psdev->pdev) {
 902                dev_err(&dev->dev, "device is not found/assigned\n");
 903                goto end;
 904        }
 905
 906        if (!psdev->pdev->sh_info) {
 907                dev_err(&dev->dev, "device is not connected or owned"
 908                        " by HVM, kill it\n");
 909                kill_domain_by_device(psdev);
 910                goto end;
 911        }
 912
 913        /*Guest owns the device yet no aer handler regiested, kill guest*/
 914        if (!test_bit(_XEN_PCIB_AERHANDLER,
 915                (unsigned long *)&psdev->pdev->sh_info->flags)) {
 916                dev_dbg(&dev->dev, "guest may have no aer driver, kill it\n");
 917                kill_domain_by_device(psdev);
 918                goto end;
 919        }
 920        result = common_process(psdev, error, XEN_PCI_OP_aer_detected, result);
 921
 922        if (result == PCI_ERS_RESULT_NONE ||
 923                result == PCI_ERS_RESULT_DISCONNECT) {
 924                dev_dbg(&dev->dev,
 925                        "No AER error_detected service or disconnected!\n");
 926                kill_domain_by_device(psdev);
 927        }
 928end:
 929        if (psdev)
 930                pcistub_device_put(psdev);
 931        up_write(&pcistub_sem);
 932        return result;
 933}
 934
 935/*xen_pcibk_error_resume: it will send the error_resume request to  pcifront
 936* in case of the device driver could provide this service, and then wait
 937* for pcifront ack.
 938* @dev: pointer to PCI devices
 939*/
 940
 941static void xen_pcibk_error_resume(struct pci_dev *dev)
 942{
 943        struct pcistub_device *psdev;
 944
 945        dev_dbg(&dev->dev, "xen_pcibk_error_resume(bus:%x,devfn:%x)\n",
 946                dev->bus->number, dev->devfn);
 947
 948        down_write(&pcistub_sem);
 949        psdev = pcistub_device_find(pci_domain_nr(dev->bus),
 950                                dev->bus->number,
 951                                PCI_SLOT(dev->devfn),
 952                                PCI_FUNC(dev->devfn));
 953
 954        if (!psdev || !psdev->pdev) {
 955                dev_err(&dev->dev, "device is not found/assigned\n");
 956                goto end;
 957        }
 958
 959        if (!psdev->pdev->sh_info) {
 960                dev_err(&dev->dev, "device is not connected or owned"
 961                        " by HVM, kill it\n");
 962                kill_domain_by_device(psdev);
 963                goto end;
 964        }
 965
 966        if (!test_bit(_XEN_PCIB_AERHANDLER,
 967                (unsigned long *)&psdev->pdev->sh_info->flags)) {
 968                dev_err(&dev->dev,
 969                        "guest with no AER driver should have been killed\n");
 970                kill_domain_by_device(psdev);
 971                goto end;
 972        }
 973        common_process(psdev, pci_channel_io_normal, XEN_PCI_OP_aer_resume,
 974                       PCI_ERS_RESULT_RECOVERED);
 975end:
 976        if (psdev)
 977                pcistub_device_put(psdev);
 978        up_write(&pcistub_sem);
 979        return;
 980}
 981
 982/*add xen_pcibk AER handling*/
 983static const struct pci_error_handlers xen_pcibk_error_handler = {
 984        .error_detected = xen_pcibk_error_detected,
 985        .mmio_enabled = xen_pcibk_mmio_enabled,
 986        .slot_reset = xen_pcibk_slot_reset,
 987        .resume = xen_pcibk_error_resume,
 988};
 989
 990/*
 991 * Note: There is no MODULE_DEVICE_TABLE entry here because this isn't
 992 * for a normal device. I don't want it to be loaded automatically.
 993 */
 994
 995static struct pci_driver xen_pcibk_pci_driver = {
 996        /* The name should be xen_pciback, but until the tools are updated
 997         * we will keep it as pciback. */
 998        .name = PCISTUB_DRIVER_NAME,
 999        .id_table = pcistub_ids,
1000        .probe = pcistub_probe,
1001        .remove = pcistub_remove,
1002        .err_handler = &xen_pcibk_error_handler,
1003};
1004
1005static inline int str_to_slot(const char *buf, int *domain, int *bus,
1006                              int *slot, int *func)
1007{
1008        int parsed = 0;
1009
1010        switch (sscanf(buf, " %x:%x:%x.%x %n", domain, bus, slot, func,
1011                       &parsed)) {
1012        case 3:
1013                *func = -1;
1014                sscanf(buf, " %x:%x:%x.* %n", domain, bus, slot, &parsed);
1015                break;
1016        case 2:
1017                *slot = *func = -1;
1018                sscanf(buf, " %x:%x:*.* %n", domain, bus, &parsed);
1019                break;
1020        }
1021        if (parsed && !buf[parsed])
1022                return 0;
1023
1024        /* try again without domain */
1025        *domain = 0;
1026        switch (sscanf(buf, " %x:%x.%x %n", bus, slot, func, &parsed)) {
1027        case 2:
1028                *func = -1;
1029                sscanf(buf, " %x:%x.* %n", bus, slot, &parsed);
1030                break;
1031        case 1:
1032                *slot = *func = -1;
1033                sscanf(buf, " %x:*.* %n", bus, &parsed);
1034                break;
1035        }
1036        if (parsed && !buf[parsed])
1037                return 0;
1038
1039        return -EINVAL;
1040}
1041
1042static inline int str_to_quirk(const char *buf, int *domain, int *bus, int
1043                               *slot, int *func, int *reg, int *size, int *mask)
1044{
1045        int parsed = 0;
1046
1047        sscanf(buf, " %x:%x:%x.%x-%x:%x:%x %n", domain, bus, slot, func,
1048               reg, size, mask, &parsed);
1049        if (parsed && !buf[parsed])
1050                return 0;
1051
1052        /* try again without domain */
1053        *domain = 0;
1054        sscanf(buf, " %x:%x.%x-%x:%x:%x %n", bus, slot, func, reg, size,
1055               mask, &parsed);
1056        if (parsed && !buf[parsed])
1057                return 0;
1058
1059        return -EINVAL;
1060}
1061
1062static int pcistub_device_id_add(int domain, int bus, int slot, int func)
1063{
1064        struct pcistub_device_id *pci_dev_id;
1065        int rc = 0, devfn = PCI_DEVFN(slot, func);
1066
1067        if (slot < 0) {
1068                for (slot = 0; !rc && slot < 32; ++slot)
1069                        rc = pcistub_device_id_add(domain, bus, slot, func);
1070                return rc;
1071        }
1072
1073        if (func < 0) {
1074                for (func = 0; !rc && func < 8; ++func)
1075                        rc = pcistub_device_id_add(domain, bus, slot, func);
1076                return rc;
1077        }
1078
1079        if ((
1080#if !defined(MODULE) /* pci_domains_supported is not being exported */ \
1081    || !defined(CONFIG_PCI_DOMAINS)
1082             !pci_domains_supported ? domain :
1083#endif
1084             domain < 0 || domain > 0xffff)
1085            || bus < 0 || bus > 0xff
1086            || PCI_SLOT(devfn) != slot
1087            || PCI_FUNC(devfn) != func)
1088                return -EINVAL;
1089
1090        pci_dev_id = kmalloc(sizeof(*pci_dev_id), GFP_KERNEL);
1091        if (!pci_dev_id)
1092                return -ENOMEM;
1093
1094        pr_debug("wants to seize %04x:%02x:%02x.%d\n",
1095                 domain, bus, slot, func);
1096
1097        pcistub_device_id_add_list(pci_dev_id, domain, bus, devfn);
1098
1099        return 0;
1100}
1101
1102static int pcistub_device_id_remove(int domain, int bus, int slot, int func)
1103{
1104        struct pcistub_device_id *pci_dev_id, *t;
1105        int err = -ENOENT;
1106        unsigned long flags;
1107
1108        spin_lock_irqsave(&device_ids_lock, flags);
1109        list_for_each_entry_safe(pci_dev_id, t, &pcistub_device_ids,
1110                                 slot_list) {
1111                if (pci_dev_id->domain == domain && pci_dev_id->bus == bus
1112                    && (slot < 0 || PCI_SLOT(pci_dev_id->devfn) == slot)
1113                    && (func < 0 || PCI_FUNC(pci_dev_id->devfn) == func)) {
1114                        /* Don't break; here because it's possible the same
1115                         * slot could be in the list more than once
1116                         */
1117                        list_del(&pci_dev_id->slot_list);
1118                        kfree(pci_dev_id);
1119
1120                        err = 0;
1121
1122                        pr_debug("removed %04x:%02x:%02x.%d from seize list\n",
1123                                 domain, bus, slot, func);
1124                }
1125        }
1126        spin_unlock_irqrestore(&device_ids_lock, flags);
1127
1128        return err;
1129}
1130
1131static int pcistub_reg_add(int domain, int bus, int slot, int func,
1132                           unsigned int reg, unsigned int size,
1133                           unsigned int mask)
1134{
1135        int err = 0;
1136        struct pcistub_device *psdev;
1137        struct pci_dev *dev;
1138        struct config_field *field;
1139
1140        if (reg > 0xfff || (size < 4 && (mask >> (size * 8))))
1141                return -EINVAL;
1142
1143        psdev = pcistub_device_find(domain, bus, slot, func);
1144        if (!psdev) {
1145                err = -ENODEV;
1146                goto out;
1147        }
1148        dev = psdev->dev;
1149
1150        field = kzalloc(sizeof(*field), GFP_KERNEL);
1151        if (!field) {
1152                err = -ENOMEM;
1153                goto out;
1154        }
1155
1156        field->offset = reg;
1157        field->size = size;
1158        field->mask = mask;
1159        field->init = NULL;
1160        field->reset = NULL;
1161        field->release = NULL;
1162        field->clean = xen_pcibk_config_field_free;
1163
1164        err = xen_pcibk_config_quirks_add_field(dev, field);
1165        if (err)
1166                kfree(field);
1167out:
1168        if (psdev)
1169                pcistub_device_put(psdev);
1170        return err;
1171}
1172
1173static ssize_t new_slot_store(struct device_driver *drv, const char *buf,
1174                              size_t count)
1175{
1176        int domain, bus, slot, func;
1177        int err;
1178
1179        err = str_to_slot(buf, &domain, &bus, &slot, &func);
1180        if (err)
1181                goto out;
1182
1183        err = pcistub_device_id_add(domain, bus, slot, func);
1184
1185out:
1186        if (!err)
1187                err = count;
1188        return err;
1189}
1190static DRIVER_ATTR_WO(new_slot);
1191
1192static ssize_t remove_slot_store(struct device_driver *drv, const char *buf,
1193                                 size_t count)
1194{
1195        int domain, bus, slot, func;
1196        int err;
1197
1198        err = str_to_slot(buf, &domain, &bus, &slot, &func);
1199        if (err)
1200                goto out;
1201
1202        err = pcistub_device_id_remove(domain, bus, slot, func);
1203
1204out:
1205        if (!err)
1206                err = count;
1207        return err;
1208}
1209static DRIVER_ATTR_WO(remove_slot);
1210
1211static ssize_t slots_show(struct device_driver *drv, char *buf)
1212{
1213        struct pcistub_device_id *pci_dev_id;
1214        size_t count = 0;
1215        unsigned long flags;
1216
1217        spin_lock_irqsave(&device_ids_lock, flags);
1218        list_for_each_entry(pci_dev_id, &pcistub_device_ids, slot_list) {
1219                if (count >= PAGE_SIZE)
1220                        break;
1221
1222                count += scnprintf(buf + count, PAGE_SIZE - count,
1223                                   "%04x:%02x:%02x.%d\n",
1224                                   pci_dev_id->domain, pci_dev_id->bus,
1225                                   PCI_SLOT(pci_dev_id->devfn),
1226                                   PCI_FUNC(pci_dev_id->devfn));
1227        }
1228        spin_unlock_irqrestore(&device_ids_lock, flags);
1229
1230        return count;
1231}
1232static DRIVER_ATTR_RO(slots);
1233
1234static ssize_t irq_handlers_show(struct device_driver *drv, char *buf)
1235{
1236        struct pcistub_device *psdev;
1237        struct xen_pcibk_dev_data *dev_data;
1238        size_t count = 0;
1239        unsigned long flags;
1240
1241        spin_lock_irqsave(&pcistub_devices_lock, flags);
1242        list_for_each_entry(psdev, &pcistub_devices, dev_list) {
1243                if (count >= PAGE_SIZE)
1244                        break;
1245                if (!psdev->dev)
1246                        continue;
1247                dev_data = pci_get_drvdata(psdev->dev);
1248                if (!dev_data)
1249                        continue;
1250                count +=
1251                    scnprintf(buf + count, PAGE_SIZE - count,
1252                              "%s:%s:%sing:%ld\n",
1253                              pci_name(psdev->dev),
1254                              dev_data->isr_on ? "on" : "off",
1255                              dev_data->ack_intr ? "ack" : "not ack",
1256                              dev_data->handled);
1257        }
1258        spin_unlock_irqrestore(&pcistub_devices_lock, flags);
1259        return count;
1260}
1261static DRIVER_ATTR_RO(irq_handlers);
1262
1263static ssize_t irq_handler_state_store(struct device_driver *drv,
1264                                       const char *buf, size_t count)
1265{
1266        struct pcistub_device *psdev;
1267        struct xen_pcibk_dev_data *dev_data;
1268        int domain, bus, slot, func;
1269        int err;
1270
1271        err = str_to_slot(buf, &domain, &bus, &slot, &func);
1272        if (err)
1273                return err;
1274
1275        psdev = pcistub_device_find(domain, bus, slot, func);
1276        if (!psdev) {
1277                err = -ENOENT;
1278                goto out;
1279        }
1280
1281        dev_data = pci_get_drvdata(psdev->dev);
1282        if (!dev_data) {
1283                err = -ENOENT;
1284                goto out;
1285        }
1286
1287        dev_dbg(&psdev->dev->dev, "%s fake irq handler: %d->%d\n",
1288                dev_data->irq_name, dev_data->isr_on,
1289                !dev_data->isr_on);
1290
1291        dev_data->isr_on = !(dev_data->isr_on);
1292        if (dev_data->isr_on)
1293                dev_data->ack_intr = 1;
1294out:
1295        if (psdev)
1296                pcistub_device_put(psdev);
1297        if (!err)
1298                err = count;
1299        return err;
1300}
1301static DRIVER_ATTR_WO(irq_handler_state);
1302
1303static ssize_t quirks_store(struct device_driver *drv, const char *buf,
1304                            size_t count)
1305{
1306        int domain, bus, slot, func, reg, size, mask;
1307        int err;
1308
1309        err = str_to_quirk(buf, &domain, &bus, &slot, &func, &reg, &size,
1310                           &mask);
1311        if (err)
1312                goto out;
1313
1314        err = pcistub_reg_add(domain, bus, slot, func, reg, size, mask);
1315
1316out:
1317        if (!err)
1318                err = count;
1319        return err;
1320}
1321
1322static ssize_t quirks_show(struct device_driver *drv, char *buf)
1323{
1324        int count = 0;
1325        unsigned long flags;
1326        struct xen_pcibk_config_quirk *quirk;
1327        struct xen_pcibk_dev_data *dev_data;
1328        const struct config_field *field;
1329        const struct config_field_entry *cfg_entry;
1330
1331        spin_lock_irqsave(&device_ids_lock, flags);
1332        list_for_each_entry(quirk, &xen_pcibk_quirks, quirks_list) {
1333                if (count >= PAGE_SIZE)
1334                        goto out;
1335
1336                count += scnprintf(buf + count, PAGE_SIZE - count,
1337                                   "%02x:%02x.%01x\n\t%04x:%04x:%04x:%04x\n",
1338                                   quirk->pdev->bus->number,
1339                                   PCI_SLOT(quirk->pdev->devfn),
1340                                   PCI_FUNC(quirk->pdev->devfn),
1341                                   quirk->devid.vendor, quirk->devid.device,
1342                                   quirk->devid.subvendor,
1343                                   quirk->devid.subdevice);
1344
1345                dev_data = pci_get_drvdata(quirk->pdev);
1346
1347                list_for_each_entry(cfg_entry, &dev_data->config_fields, list) {
1348                        field = cfg_entry->field;
1349                        if (count >= PAGE_SIZE)
1350                                goto out;
1351
1352                        count += scnprintf(buf + count, PAGE_SIZE - count,
1353                                           "\t\t%08x:%01x:%08x\n",
1354                                           cfg_entry->base_offset +
1355                                           field->offset, field->size,
1356                                           field->mask);
1357                }
1358        }
1359
1360out:
1361        spin_unlock_irqrestore(&device_ids_lock, flags);
1362
1363        return count;
1364}
1365static DRIVER_ATTR_RW(quirks);
1366
1367static ssize_t permissive_store(struct device_driver *drv, const char *buf,
1368                                size_t count)
1369{
1370        int domain, bus, slot, func;
1371        int err;
1372        struct pcistub_device *psdev;
1373        struct xen_pcibk_dev_data *dev_data;
1374
1375        err = str_to_slot(buf, &domain, &bus, &slot, &func);
1376        if (err)
1377                goto out;
1378
1379        psdev = pcistub_device_find(domain, bus, slot, func);
1380        if (!psdev) {
1381                err = -ENODEV;
1382                goto out;
1383        }
1384
1385        dev_data = pci_get_drvdata(psdev->dev);
1386        /* the driver data for a device should never be null at this point */
1387        if (!dev_data) {
1388                err = -ENXIO;
1389                goto release;
1390        }
1391        if (!dev_data->permissive) {
1392                dev_data->permissive = 1;
1393                /* Let user know that what they're doing could be unsafe */
1394                dev_warn(&psdev->dev->dev, "enabling permissive mode "
1395                         "configuration space accesses!\n");
1396                dev_warn(&psdev->dev->dev,
1397                         "permissive mode is potentially unsafe!\n");
1398        }
1399release:
1400        pcistub_device_put(psdev);
1401out:
1402        if (!err)
1403                err = count;
1404        return err;
1405}
1406
1407static ssize_t permissive_show(struct device_driver *drv, char *buf)
1408{
1409        struct pcistub_device *psdev;
1410        struct xen_pcibk_dev_data *dev_data;
1411        size_t count = 0;
1412        unsigned long flags;
1413        spin_lock_irqsave(&pcistub_devices_lock, flags);
1414        list_for_each_entry(psdev, &pcistub_devices, dev_list) {
1415                if (count >= PAGE_SIZE)
1416                        break;
1417                if (!psdev->dev)
1418                        continue;
1419                dev_data = pci_get_drvdata(psdev->dev);
1420                if (!dev_data || !dev_data->permissive)
1421                        continue;
1422                count +=
1423                    scnprintf(buf + count, PAGE_SIZE - count, "%s\n",
1424                              pci_name(psdev->dev));
1425        }
1426        spin_unlock_irqrestore(&pcistub_devices_lock, flags);
1427        return count;
1428}
1429static DRIVER_ATTR_RW(permissive);
1430
1431static ssize_t allow_interrupt_control_store(struct device_driver *drv,
1432                                             const char *buf, size_t count)
1433{
1434        int domain, bus, slot, func;
1435        int err;
1436        struct pcistub_device *psdev;
1437        struct xen_pcibk_dev_data *dev_data;
1438
1439        err = str_to_slot(buf, &domain, &bus, &slot, &func);
1440        if (err)
1441                goto out;
1442
1443        psdev = pcistub_device_find(domain, bus, slot, func);
1444        if (!psdev) {
1445                err = -ENODEV;
1446                goto out;
1447        }
1448
1449        dev_data = pci_get_drvdata(psdev->dev);
1450        /* the driver data for a device should never be null at this point */
1451        if (!dev_data) {
1452                err = -ENXIO;
1453                goto release;
1454        }
1455        dev_data->allow_interrupt_control = 1;
1456release:
1457        pcistub_device_put(psdev);
1458out:
1459        if (!err)
1460                err = count;
1461        return err;
1462}
1463
1464static ssize_t allow_interrupt_control_show(struct device_driver *drv,
1465                                            char *buf)
1466{
1467        struct pcistub_device *psdev;
1468        struct xen_pcibk_dev_data *dev_data;
1469        size_t count = 0;
1470        unsigned long flags;
1471
1472        spin_lock_irqsave(&pcistub_devices_lock, flags);
1473        list_for_each_entry(psdev, &pcistub_devices, dev_list) {
1474                if (count >= PAGE_SIZE)
1475                        break;
1476                if (!psdev->dev)
1477                        continue;
1478                dev_data = pci_get_drvdata(psdev->dev);
1479                if (!dev_data || !dev_data->allow_interrupt_control)
1480                        continue;
1481                count +=
1482                    scnprintf(buf + count, PAGE_SIZE - count, "%s\n",
1483                              pci_name(psdev->dev));
1484        }
1485        spin_unlock_irqrestore(&pcistub_devices_lock, flags);
1486        return count;
1487}
1488static DRIVER_ATTR_RW(allow_interrupt_control);
1489
1490static void pcistub_exit(void)
1491{
1492        driver_remove_file(&xen_pcibk_pci_driver.driver, &driver_attr_new_slot);
1493        driver_remove_file(&xen_pcibk_pci_driver.driver,
1494                           &driver_attr_remove_slot);
1495        driver_remove_file(&xen_pcibk_pci_driver.driver, &driver_attr_slots);
1496        driver_remove_file(&xen_pcibk_pci_driver.driver, &driver_attr_quirks);
1497        driver_remove_file(&xen_pcibk_pci_driver.driver,
1498                           &driver_attr_permissive);
1499        driver_remove_file(&xen_pcibk_pci_driver.driver,
1500                           &driver_attr_allow_interrupt_control);
1501        driver_remove_file(&xen_pcibk_pci_driver.driver,
1502                           &driver_attr_irq_handlers);
1503        driver_remove_file(&xen_pcibk_pci_driver.driver,
1504                           &driver_attr_irq_handler_state);
1505        pci_unregister_driver(&xen_pcibk_pci_driver);
1506}
1507
1508static int __init pcistub_init(void)
1509{
1510        int pos = 0;
1511        int err = 0;
1512        int domain, bus, slot, func;
1513        int parsed;
1514
1515        if (pci_devs_to_hide && *pci_devs_to_hide) {
1516                do {
1517                        parsed = 0;
1518
1519                        err = sscanf(pci_devs_to_hide + pos,
1520                                     " (%x:%x:%x.%x) %n",
1521                                     &domain, &bus, &slot, &func, &parsed);
1522                        switch (err) {
1523                        case 3:
1524                                func = -1;
1525                                sscanf(pci_devs_to_hide + pos,
1526                                       " (%x:%x:%x.*) %n",
1527                                       &domain, &bus, &slot, &parsed);
1528                                break;
1529                        case 2:
1530                                slot = func = -1;
1531                                sscanf(pci_devs_to_hide + pos,
1532                                       " (%x:%x:*.*) %n",
1533                                       &domain, &bus, &parsed);
1534                                break;
1535                        }
1536
1537                        if (!parsed) {
1538                                domain = 0;
1539                                err = sscanf(pci_devs_to_hide + pos,
1540                                             " (%x:%x.%x) %n",
1541                                             &bus, &slot, &func, &parsed);
1542                                switch (err) {
1543                                case 2:
1544                                        func = -1;
1545                                        sscanf(pci_devs_to_hide + pos,
1546                                               " (%x:%x.*) %n",
1547                                               &bus, &slot, &parsed);
1548                                        break;
1549                                case 1:
1550                                        slot = func = -1;
1551                                        sscanf(pci_devs_to_hide + pos,
1552                                               " (%x:*.*) %n",
1553                                               &bus, &parsed);
1554                                        break;
1555                                }
1556                        }
1557
1558                        if (parsed <= 0)
1559                                goto parse_error;
1560
1561                        err = pcistub_device_id_add(domain, bus, slot, func);
1562                        if (err)
1563                                goto out;
1564
1565                        pos += parsed;
1566                } while (pci_devs_to_hide[pos]);
1567        }
1568
1569        /* If we're the first PCI Device Driver to register, we're the
1570         * first one to get offered PCI devices as they become
1571         * available (and thus we can be the first to grab them)
1572         */
1573        err = pci_register_driver(&xen_pcibk_pci_driver);
1574        if (err < 0)
1575                goto out;
1576
1577        err = driver_create_file(&xen_pcibk_pci_driver.driver,
1578                                 &driver_attr_new_slot);
1579        if (!err)
1580                err = driver_create_file(&xen_pcibk_pci_driver.driver,
1581                                         &driver_attr_remove_slot);
1582        if (!err)
1583                err = driver_create_file(&xen_pcibk_pci_driver.driver,
1584                                         &driver_attr_slots);
1585        if (!err)
1586                err = driver_create_file(&xen_pcibk_pci_driver.driver,
1587                                         &driver_attr_quirks);
1588        if (!err)
1589                err = driver_create_file(&xen_pcibk_pci_driver.driver,
1590                                         &driver_attr_permissive);
1591        if (!err)
1592                err = driver_create_file(&xen_pcibk_pci_driver.driver,
1593                                         &driver_attr_allow_interrupt_control);
1594
1595        if (!err)
1596                err = driver_create_file(&xen_pcibk_pci_driver.driver,
1597                                         &driver_attr_irq_handlers);
1598        if (!err)
1599                err = driver_create_file(&xen_pcibk_pci_driver.driver,
1600                                        &driver_attr_irq_handler_state);
1601        if (err)
1602                pcistub_exit();
1603
1604out:
1605        return err;
1606
1607parse_error:
1608        pr_err("Error parsing pci_devs_to_hide at \"%s\"\n",
1609               pci_devs_to_hide + pos);
1610        return -EINVAL;
1611}
1612
1613#ifndef MODULE
1614/*
1615 * fs_initcall happens before device_initcall
1616 * so xen_pcibk *should* get called first (b/c we
1617 * want to suck up any device before other drivers
1618 * get a chance by being the first pci device
1619 * driver to register)
1620 */
1621fs_initcall(pcistub_init);
1622#endif
1623
1624#ifdef CONFIG_PCI_IOV
1625static struct pcistub_device *find_vfs(const struct pci_dev *pdev)
1626{
1627        struct pcistub_device *psdev = NULL;
1628        unsigned long flags;
1629        bool found = false;
1630
1631        spin_lock_irqsave(&pcistub_devices_lock, flags);
1632        list_for_each_entry(psdev, &pcistub_devices, dev_list) {
1633                if (!psdev->pdev && psdev->dev != pdev
1634                    && pci_physfn(psdev->dev) == pdev) {
1635                        found = true;
1636                        break;
1637                }
1638        }
1639        spin_unlock_irqrestore(&pcistub_devices_lock, flags);
1640        if (found)
1641                return psdev;
1642        return NULL;
1643}
1644
1645static int pci_stub_notifier(struct notifier_block *nb,
1646                             unsigned long action, void *data)
1647{
1648        struct device *dev = data;
1649        const struct pci_dev *pdev = to_pci_dev(dev);
1650
1651        if (action != BUS_NOTIFY_UNBIND_DRIVER)
1652                return NOTIFY_DONE;
1653
1654        if (!pdev->is_physfn)
1655                return NOTIFY_DONE;
1656
1657        for (;;) {
1658                struct pcistub_device *psdev = find_vfs(pdev);
1659                if (!psdev)
1660                        break;
1661                device_release_driver(&psdev->dev->dev);
1662        }
1663        return NOTIFY_DONE;
1664}
1665
1666static struct notifier_block pci_stub_nb = {
1667        .notifier_call = pci_stub_notifier,
1668};
1669#endif
1670
1671static int __init xen_pcibk_init(void)
1672{
1673        int err;
1674
1675        if (!xen_initial_domain())
1676                return -ENODEV;
1677
1678        err = xen_pcibk_config_init();
1679        if (err)
1680                return err;
1681
1682#ifdef MODULE
1683        err = pcistub_init();
1684        if (err < 0)
1685                return err;
1686#endif
1687
1688        pcistub_init_devices_late();
1689        err = xen_pcibk_xenbus_register();
1690        if (err)
1691                pcistub_exit();
1692#ifdef CONFIG_PCI_IOV
1693        else
1694                bus_register_notifier(&pci_bus_type, &pci_stub_nb);
1695#endif
1696
1697        return err;
1698}
1699
1700static void __exit xen_pcibk_cleanup(void)
1701{
1702#ifdef CONFIG_PCI_IOV
1703        bus_unregister_notifier(&pci_bus_type, &pci_stub_nb);
1704#endif
1705        xen_pcibk_xenbus_unregister();
1706        pcistub_exit();
1707}
1708
1709module_init(xen_pcibk_init);
1710module_exit(xen_pcibk_cleanup);
1711
1712MODULE_LICENSE("Dual BSD/GPL");
1713MODULE_ALIAS("xen-backend:pci");
1714