Merge tag 'stable/for-linus-3.8-rc0-tag' of git://git.kernel.org/pub/scm/linux/kernel...
[~shefty/rdma-dev.git] / drivers / xen / xen-pciback / pci_stub.c
1 /*
2  * PCI Stub Driver - Grabs devices in backend to be exported later
3  *
4  * Ryan Wilson <hap9@epoch.ncsc.mil>
5  * Chris Bookholt <hap10@epoch.ncsc.mil>
6  */
7 #include <linux/module.h>
8 #include <linux/init.h>
9 #include <linux/rwsem.h>
10 #include <linux/list.h>
11 #include <linux/spinlock.h>
12 #include <linux/kref.h>
13 #include <linux/pci.h>
14 #include <linux/wait.h>
15 #include <linux/sched.h>
16 #include <linux/atomic.h>
17 #include <xen/events.h>
18 #include <asm/xen/pci.h>
19 #include <asm/xen/hypervisor.h>
20 #include "pciback.h"
21 #include "conf_space.h"
22 #include "conf_space_quirks.h"
23
24 static char *pci_devs_to_hide;
25 wait_queue_head_t xen_pcibk_aer_wait_queue;
26 /*Add sem for sync AER handling and xen_pcibk remove/reconfigue ops,
27 * We want to avoid in middle of AER ops, xen_pcibk devices is being removed
28 */
29 static DECLARE_RWSEM(pcistub_sem);
30 module_param_named(hide, pci_devs_to_hide, charp, 0444);
31
32 struct pcistub_device_id {
33         struct list_head slot_list;
34         int domain;
35         unsigned char bus;
36         unsigned int devfn;
37 };
38 static LIST_HEAD(pcistub_device_ids);
39 static DEFINE_SPINLOCK(device_ids_lock);
40
41 struct pcistub_device {
42         struct kref kref;
43         struct list_head dev_list;
44         spinlock_t lock;
45
46         struct pci_dev *dev;
47         struct xen_pcibk_device *pdev;/* non-NULL if struct pci_dev is in use */
48 };
49
50 /* Access to pcistub_devices & seized_devices lists and the initialize_devices
51  * flag must be locked with pcistub_devices_lock
52  */
53 static DEFINE_SPINLOCK(pcistub_devices_lock);
54 static LIST_HEAD(pcistub_devices);
55
56 /* wait for device_initcall before initializing our devices
57  * (see pcistub_init_devices_late)
58  */
59 static int initialize_devices;
60 static LIST_HEAD(seized_devices);
61
62 static struct pcistub_device *pcistub_device_alloc(struct pci_dev *dev)
63 {
64         struct pcistub_device *psdev;
65
66         dev_dbg(&dev->dev, "pcistub_device_alloc\n");
67
68         psdev = kzalloc(sizeof(*psdev), GFP_ATOMIC);
69         if (!psdev)
70                 return NULL;
71
72         psdev->dev = pci_dev_get(dev);
73         if (!psdev->dev) {
74                 kfree(psdev);
75                 return NULL;
76         }
77
78         kref_init(&psdev->kref);
79         spin_lock_init(&psdev->lock);
80
81         return psdev;
82 }
83
84 /* Don't call this directly as it's called by pcistub_device_put */
85 static void pcistub_device_release(struct kref *kref)
86 {
87         struct pcistub_device *psdev;
88         struct xen_pcibk_dev_data *dev_data;
89
90         psdev = container_of(kref, struct pcistub_device, kref);
91         dev_data = pci_get_drvdata(psdev->dev);
92
93         dev_dbg(&psdev->dev->dev, "pcistub_device_release\n");
94
95         xen_unregister_device_domain_owner(psdev->dev);
96
97         /* Call the reset function which does not take lock as this
98          * is called from "unbind" which takes a device_lock mutex.
99          */
100         __pci_reset_function_locked(psdev->dev);
101         if (pci_load_and_free_saved_state(psdev->dev,
102                                           &dev_data->pci_saved_state)) {
103                 dev_dbg(&psdev->dev->dev, "Could not reload PCI state\n");
104         } else
105                 pci_restore_state(psdev->dev);
106
107         /* Disable the device */
108         xen_pcibk_reset_device(psdev->dev);
109
110         kfree(dev_data);
111         pci_set_drvdata(psdev->dev, NULL);
112
113         /* Clean-up the device */
114         xen_pcibk_config_free_dyn_fields(psdev->dev);
115         xen_pcibk_config_free_dev(psdev->dev);
116
117         psdev->dev->dev_flags &= ~PCI_DEV_FLAGS_ASSIGNED;
118         pci_dev_put(psdev->dev);
119
120         kfree(psdev);
121 }
122
123 static inline void pcistub_device_get(struct pcistub_device *psdev)
124 {
125         kref_get(&psdev->kref);
126 }
127
128 static inline void pcistub_device_put(struct pcistub_device *psdev)
129 {
130         kref_put(&psdev->kref, pcistub_device_release);
131 }
132
133 static struct pcistub_device *pcistub_device_find(int domain, int bus,
134                                                   int slot, int func)
135 {
136         struct pcistub_device *psdev = NULL;
137         unsigned long flags;
138
139         spin_lock_irqsave(&pcistub_devices_lock, flags);
140
141         list_for_each_entry(psdev, &pcistub_devices, dev_list) {
142                 if (psdev->dev != NULL
143                     && domain == pci_domain_nr(psdev->dev->bus)
144                     && bus == psdev->dev->bus->number
145                     && slot == PCI_SLOT(psdev->dev->devfn)
146                     && func == PCI_FUNC(psdev->dev->devfn)) {
147                         pcistub_device_get(psdev);
148                         goto out;
149                 }
150         }
151
152         /* didn't find it */
153         psdev = NULL;
154
155 out:
156         spin_unlock_irqrestore(&pcistub_devices_lock, flags);
157         return psdev;
158 }
159
160 static struct pci_dev *pcistub_device_get_pci_dev(struct xen_pcibk_device *pdev,
161                                                   struct pcistub_device *psdev)
162 {
163         struct pci_dev *pci_dev = NULL;
164         unsigned long flags;
165
166         pcistub_device_get(psdev);
167
168         spin_lock_irqsave(&psdev->lock, flags);
169         if (!psdev->pdev) {
170                 psdev->pdev = pdev;
171                 pci_dev = psdev->dev;
172         }
173         spin_unlock_irqrestore(&psdev->lock, flags);
174
175         if (!pci_dev)
176                 pcistub_device_put(psdev);
177
178         return pci_dev;
179 }
180
181 struct pci_dev *pcistub_get_pci_dev_by_slot(struct xen_pcibk_device *pdev,
182                                             int domain, int bus,
183                                             int slot, int func)
184 {
185         struct pcistub_device *psdev;
186         struct pci_dev *found_dev = NULL;
187         unsigned long flags;
188
189         spin_lock_irqsave(&pcistub_devices_lock, flags);
190
191         list_for_each_entry(psdev, &pcistub_devices, dev_list) {
192                 if (psdev->dev != NULL
193                     && domain == pci_domain_nr(psdev->dev->bus)
194                     && bus == psdev->dev->bus->number
195                     && slot == PCI_SLOT(psdev->dev->devfn)
196                     && func == PCI_FUNC(psdev->dev->devfn)) {
197                         found_dev = pcistub_device_get_pci_dev(pdev, psdev);
198                         break;
199                 }
200         }
201
202         spin_unlock_irqrestore(&pcistub_devices_lock, flags);
203         return found_dev;
204 }
205
206 struct pci_dev *pcistub_get_pci_dev(struct xen_pcibk_device *pdev,
207                                     struct pci_dev *dev)
208 {
209         struct pcistub_device *psdev;
210         struct pci_dev *found_dev = NULL;
211         unsigned long flags;
212
213         spin_lock_irqsave(&pcistub_devices_lock, flags);
214
215         list_for_each_entry(psdev, &pcistub_devices, dev_list) {
216                 if (psdev->dev == dev) {
217                         found_dev = pcistub_device_get_pci_dev(pdev, psdev);
218                         break;
219                 }
220         }
221
222         spin_unlock_irqrestore(&pcistub_devices_lock, flags);
223         return found_dev;
224 }
225
226 void pcistub_put_pci_dev(struct pci_dev *dev)
227 {
228         struct pcistub_device *psdev, *found_psdev = NULL;
229         unsigned long flags;
230
231         spin_lock_irqsave(&pcistub_devices_lock, flags);
232
233         list_for_each_entry(psdev, &pcistub_devices, dev_list) {
234                 if (psdev->dev == dev) {
235                         found_psdev = psdev;
236                         break;
237                 }
238         }
239
240         spin_unlock_irqrestore(&pcistub_devices_lock, flags);
241         if (WARN_ON(!found_psdev))
242                 return;
243
244         /*hold this lock for avoiding breaking link between
245         * pcistub and xen_pcibk when AER is in processing
246         */
247         down_write(&pcistub_sem);
248         /* Cleanup our device
249          * (so it's ready for the next domain)
250          */
251
252         /* This is OK - we are running from workqueue context
253          * and want to inhibit the user from fiddling with 'reset'
254          */
255         pci_reset_function(dev);
256         pci_restore_state(psdev->dev);
257
258         /* This disables the device. */
259         xen_pcibk_reset_device(found_psdev->dev);
260
261         /* And cleanup up our emulated fields. */
262         xen_pcibk_config_free_dyn_fields(found_psdev->dev);
263         xen_pcibk_config_reset_dev(found_psdev->dev);
264
265         xen_unregister_device_domain_owner(found_psdev->dev);
266
267         spin_lock_irqsave(&found_psdev->lock, flags);
268         found_psdev->pdev = NULL;
269         spin_unlock_irqrestore(&found_psdev->lock, flags);
270
271         pcistub_device_put(found_psdev);
272         up_write(&pcistub_sem);
273 }
274
275 static int __devinit pcistub_match_one(struct pci_dev *dev,
276                                        struct pcistub_device_id *pdev_id)
277 {
278         /* Match the specified device by domain, bus, slot, func and also if
279          * any of the device's parent bridges match.
280          */
281         for (; dev != NULL; dev = dev->bus->self) {
282                 if (pci_domain_nr(dev->bus) == pdev_id->domain
283                     && dev->bus->number == pdev_id->bus
284                     && dev->devfn == pdev_id->devfn)
285                         return 1;
286
287                 /* Sometimes topmost bridge links to itself. */
288                 if (dev == dev->bus->self)
289                         break;
290         }
291
292         return 0;
293 }
294
295 static int __devinit pcistub_match(struct pci_dev *dev)
296 {
297         struct pcistub_device_id *pdev_id;
298         unsigned long flags;
299         int found = 0;
300
301         spin_lock_irqsave(&device_ids_lock, flags);
302         list_for_each_entry(pdev_id, &pcistub_device_ids, slot_list) {
303                 if (pcistub_match_one(dev, pdev_id)) {
304                         found = 1;
305                         break;
306                 }
307         }
308         spin_unlock_irqrestore(&device_ids_lock, flags);
309
310         return found;
311 }
312
313 static int __devinit pcistub_init_device(struct pci_dev *dev)
314 {
315         struct xen_pcibk_dev_data *dev_data;
316         int err = 0;
317
318         dev_dbg(&dev->dev, "initializing...\n");
319
320         /* The PCI backend is not intended to be a module (or to work with
321          * removable PCI devices (yet). If it were, xen_pcibk_config_free()
322          * would need to be called somewhere to free the memory allocated
323          * here and then to call kfree(pci_get_drvdata(psdev->dev)).
324          */
325         dev_data = kzalloc(sizeof(*dev_data) +  strlen(DRV_NAME "[]")
326                                 + strlen(pci_name(dev)) + 1, GFP_ATOMIC);
327         if (!dev_data) {
328                 err = -ENOMEM;
329                 goto out;
330         }
331         pci_set_drvdata(dev, dev_data);
332
333         /*
334          * Setup name for fake IRQ handler. It will only be enabled
335          * once the device is turned on by the guest.
336          */
337         sprintf(dev_data->irq_name, DRV_NAME "[%s]", pci_name(dev));
338
339         dev_dbg(&dev->dev, "initializing config\n");
340
341         init_waitqueue_head(&xen_pcibk_aer_wait_queue);
342         err = xen_pcibk_config_init_dev(dev);
343         if (err)
344                 goto out;
345
346         /* HACK: Force device (& ACPI) to determine what IRQ it's on - we
347          * must do this here because pcibios_enable_device may specify
348          * the pci device's true irq (and possibly its other resources)
349          * if they differ from what's in the configuration space.
350          * This makes the assumption that the device's resources won't
351          * change after this point (otherwise this code may break!)
352          */
353         dev_dbg(&dev->dev, "enabling device\n");
354         err = pci_enable_device(dev);
355         if (err)
356                 goto config_release;
357
358         /* We need the device active to save the state. */
359         dev_dbg(&dev->dev, "save state of device\n");
360         pci_save_state(dev);
361         dev_data->pci_saved_state = pci_store_saved_state(dev);
362         if (!dev_data->pci_saved_state)
363                 dev_err(&dev->dev, "Could not store PCI conf saved state!\n");
364         else {
365                 dev_dbg(&dev->dev, "resetting (FLR, D3, etc) the device\n");
366                 __pci_reset_function_locked(dev);
367                 pci_restore_state(dev);
368         }
369         /* Now disable the device (this also ensures some private device
370          * data is setup before we export)
371          */
372         dev_dbg(&dev->dev, "reset device\n");
373         xen_pcibk_reset_device(dev);
374
375         dev->dev_flags |= PCI_DEV_FLAGS_ASSIGNED;
376         return 0;
377
378 config_release:
379         xen_pcibk_config_free_dev(dev);
380
381 out:
382         pci_set_drvdata(dev, NULL);
383         kfree(dev_data);
384         return err;
385 }
386
387 /*
388  * Because some initialization still happens on
389  * devices during fs_initcall, we need to defer
390  * full initialization of our devices until
391  * device_initcall.
392  */
393 static int __init pcistub_init_devices_late(void)
394 {
395         struct pcistub_device *psdev;
396         unsigned long flags;
397         int err = 0;
398
399         pr_debug(DRV_NAME ": pcistub_init_devices_late\n");
400
401         spin_lock_irqsave(&pcistub_devices_lock, flags);
402
403         while (!list_empty(&seized_devices)) {
404                 psdev = container_of(seized_devices.next,
405                                      struct pcistub_device, dev_list);
406                 list_del(&psdev->dev_list);
407
408                 spin_unlock_irqrestore(&pcistub_devices_lock, flags);
409
410                 err = pcistub_init_device(psdev->dev);
411                 if (err) {
412                         dev_err(&psdev->dev->dev,
413                                 "error %d initializing device\n", err);
414                         kfree(psdev);
415                         psdev = NULL;
416                 }
417
418                 spin_lock_irqsave(&pcistub_devices_lock, flags);
419
420                 if (psdev)
421                         list_add_tail(&psdev->dev_list, &pcistub_devices);
422         }
423
424         initialize_devices = 1;
425
426         spin_unlock_irqrestore(&pcistub_devices_lock, flags);
427
428         return 0;
429 }
430
431 static int __devinit pcistub_seize(struct pci_dev *dev)
432 {
433         struct pcistub_device *psdev;
434         unsigned long flags;
435         int err = 0;
436
437         psdev = pcistub_device_alloc(dev);
438         if (!psdev)
439                 return -ENOMEM;
440
441         spin_lock_irqsave(&pcistub_devices_lock, flags);
442
443         if (initialize_devices) {
444                 spin_unlock_irqrestore(&pcistub_devices_lock, flags);
445
446                 /* don't want irqs disabled when calling pcistub_init_device */
447                 err = pcistub_init_device(psdev->dev);
448
449                 spin_lock_irqsave(&pcistub_devices_lock, flags);
450
451                 if (!err)
452                         list_add(&psdev->dev_list, &pcistub_devices);
453         } else {
454                 dev_dbg(&dev->dev, "deferring initialization\n");
455                 list_add(&psdev->dev_list, &seized_devices);
456         }
457
458         spin_unlock_irqrestore(&pcistub_devices_lock, flags);
459
460         if (err)
461                 pcistub_device_put(psdev);
462
463         return err;
464 }
465
466 static int __devinit pcistub_probe(struct pci_dev *dev,
467                                    const struct pci_device_id *id)
468 {
469         int err = 0;
470
471         dev_dbg(&dev->dev, "probing...\n");
472
473         if (pcistub_match(dev)) {
474
475                 if (dev->hdr_type != PCI_HEADER_TYPE_NORMAL
476                     && dev->hdr_type != PCI_HEADER_TYPE_BRIDGE) {
477                         dev_err(&dev->dev, "can't export pci devices that "
478                                 "don't have a normal (0) or bridge (1) "
479                                 "header type!\n");
480                         err = -ENODEV;
481                         goto out;
482                 }
483
484                 dev_info(&dev->dev, "seizing device\n");
485                 err = pcistub_seize(dev);
486         } else
487                 /* Didn't find the device */
488                 err = -ENODEV;
489
490 out:
491         return err;
492 }
493
494 static void pcistub_remove(struct pci_dev *dev)
495 {
496         struct pcistub_device *psdev, *found_psdev = NULL;
497         unsigned long flags;
498
499         dev_dbg(&dev->dev, "removing\n");
500
501         spin_lock_irqsave(&pcistub_devices_lock, flags);
502
503         xen_pcibk_config_quirk_release(dev);
504
505         list_for_each_entry(psdev, &pcistub_devices, dev_list) {
506                 if (psdev->dev == dev) {
507                         found_psdev = psdev;
508                         break;
509                 }
510         }
511
512         spin_unlock_irqrestore(&pcistub_devices_lock, flags);
513
514         if (found_psdev) {
515                 dev_dbg(&dev->dev, "found device to remove - in use? %p\n",
516                         found_psdev->pdev);
517
518                 if (found_psdev->pdev) {
519                         printk(KERN_WARNING DRV_NAME ": ****** removing device "
520                                "%s while still in-use! ******\n",
521                                pci_name(found_psdev->dev));
522                         printk(KERN_WARNING DRV_NAME ": ****** driver domain may"
523                                " still access this device's i/o resources!\n");
524                         printk(KERN_WARNING DRV_NAME ": ****** shutdown driver "
525                                "domain before binding device\n");
526                         printk(KERN_WARNING DRV_NAME ": ****** to other drivers "
527                                "or domains\n");
528
529                         xen_pcibk_release_pci_dev(found_psdev->pdev,
530                                                 found_psdev->dev);
531                 }
532
533                 spin_lock_irqsave(&pcistub_devices_lock, flags);
534                 list_del(&found_psdev->dev_list);
535                 spin_unlock_irqrestore(&pcistub_devices_lock, flags);
536
537                 /* the final put for releasing from the list */
538                 pcistub_device_put(found_psdev);
539         }
540 }
541
542 static DEFINE_PCI_DEVICE_TABLE(pcistub_ids) = {
543         {
544          .vendor = PCI_ANY_ID,
545          .device = PCI_ANY_ID,
546          .subvendor = PCI_ANY_ID,
547          .subdevice = PCI_ANY_ID,
548          },
549         {0,},
550 };
551
552 #define PCI_NODENAME_MAX 40
553 static void kill_domain_by_device(struct pcistub_device *psdev)
554 {
555         struct xenbus_transaction xbt;
556         int err;
557         char nodename[PCI_NODENAME_MAX];
558
559         BUG_ON(!psdev);
560         snprintf(nodename, PCI_NODENAME_MAX, "/local/domain/0/backend/pci/%d/0",
561                 psdev->pdev->xdev->otherend_id);
562
563 again:
564         err = xenbus_transaction_start(&xbt);
565         if (err) {
566                 dev_err(&psdev->dev->dev,
567                         "error %d when start xenbus transaction\n", err);
568                 return;
569         }
570         /*PV AER handlers will set this flag*/
571         xenbus_printf(xbt, nodename, "aerState" , "aerfail");
572         err = xenbus_transaction_end(xbt, 0);
573         if (err) {
574                 if (err == -EAGAIN)
575                         goto again;
576                 dev_err(&psdev->dev->dev,
577                         "error %d when end xenbus transaction\n", err);
578                 return;
579         }
580 }
581
582 /* For each aer recovery step error_detected, mmio_enabled, etc, front_end and
583  * backend need to have cooperation. In xen_pcibk, those steps will do similar
584  * jobs: send service request and waiting for front_end response.
585 */
586 static pci_ers_result_t common_process(struct pcistub_device *psdev,
587                                        pci_channel_state_t state, int aer_cmd,
588                                        pci_ers_result_t result)
589 {
590         pci_ers_result_t res = result;
591         struct xen_pcie_aer_op *aer_op;
592         int ret;
593
594         /*with PV AER drivers*/
595         aer_op = &(psdev->pdev->sh_info->aer_op);
596         aer_op->cmd = aer_cmd ;
597         /*useful for error_detected callback*/
598         aer_op->err = state;
599         /*pcifront_end BDF*/
600         ret = xen_pcibk_get_pcifront_dev(psdev->dev, psdev->pdev,
601                 &aer_op->domain, &aer_op->bus, &aer_op->devfn);
602         if (!ret) {
603                 dev_err(&psdev->dev->dev,
604                         DRV_NAME ": failed to get pcifront device\n");
605                 return PCI_ERS_RESULT_NONE;
606         }
607         wmb();
608
609         dev_dbg(&psdev->dev->dev,
610                         DRV_NAME ": aer_op %x dom %x bus %x devfn %x\n",
611                         aer_cmd, aer_op->domain, aer_op->bus, aer_op->devfn);
612         /*local flag to mark there's aer request, xen_pcibk callback will use
613         * this flag to judge whether we need to check pci-front give aer
614         * service ack signal
615         */
616         set_bit(_PCIB_op_pending, (unsigned long *)&psdev->pdev->flags);
617
618         /*It is possible that a pcifront conf_read_write ops request invokes
619         * the callback which cause the spurious execution of wake_up.
620         * Yet it is harmless and better than a spinlock here
621         */
622         set_bit(_XEN_PCIB_active,
623                 (unsigned long *)&psdev->pdev->sh_info->flags);
624         wmb();
625         notify_remote_via_irq(psdev->pdev->evtchn_irq);
626
627         ret = wait_event_timeout(xen_pcibk_aer_wait_queue,
628                                  !(test_bit(_XEN_PCIB_active, (unsigned long *)
629                                  &psdev->pdev->sh_info->flags)), 300*HZ);
630
631         if (!ret) {
632                 if (test_bit(_XEN_PCIB_active,
633                         (unsigned long *)&psdev->pdev->sh_info->flags)) {
634                         dev_err(&psdev->dev->dev,
635                                 "pcifront aer process not responding!\n");
636                         clear_bit(_XEN_PCIB_active,
637                           (unsigned long *)&psdev->pdev->sh_info->flags);
638                         aer_op->err = PCI_ERS_RESULT_NONE;
639                         return res;
640                 }
641         }
642         clear_bit(_PCIB_op_pending, (unsigned long *)&psdev->pdev->flags);
643
644         if (test_bit(_XEN_PCIF_active,
645                 (unsigned long *)&psdev->pdev->sh_info->flags)) {
646                 dev_dbg(&psdev->dev->dev,
647                         "schedule pci_conf service in " DRV_NAME "\n");
648                 xen_pcibk_test_and_schedule_op(psdev->pdev);
649         }
650
651         res = (pci_ers_result_t)aer_op->err;
652         return res;
653 }
654
655 /*
656 * xen_pcibk_slot_reset: it will send the slot_reset request to  pcifront in case
657 * of the device driver could provide this service, and then wait for pcifront
658 * ack.
659 * @dev: pointer to PCI devices
660 * return value is used by aer_core do_recovery policy
661 */
662 static pci_ers_result_t xen_pcibk_slot_reset(struct pci_dev *dev)
663 {
664         struct pcistub_device *psdev;
665         pci_ers_result_t result;
666
667         result = PCI_ERS_RESULT_RECOVERED;
668         dev_dbg(&dev->dev, "xen_pcibk_slot_reset(bus:%x,devfn:%x)\n",
669                 dev->bus->number, dev->devfn);
670
671         down_write(&pcistub_sem);
672         psdev = pcistub_device_find(pci_domain_nr(dev->bus),
673                                 dev->bus->number,
674                                 PCI_SLOT(dev->devfn),
675                                 PCI_FUNC(dev->devfn));
676
677         if (!psdev || !psdev->pdev) {
678                 dev_err(&dev->dev,
679                         DRV_NAME " device is not found/assigned\n");
680                 goto end;
681         }
682
683         if (!psdev->pdev->sh_info) {
684                 dev_err(&dev->dev, DRV_NAME " device is not connected or owned"
685                         " by HVM, kill it\n");
686                 kill_domain_by_device(psdev);
687                 goto end;
688         }
689
690         if (!test_bit(_XEN_PCIB_AERHANDLER,
691                 (unsigned long *)&psdev->pdev->sh_info->flags)) {
692                 dev_err(&dev->dev,
693                         "guest with no AER driver should have been killed\n");
694                 goto end;
695         }
696         result = common_process(psdev, 1, XEN_PCI_OP_aer_slotreset, result);
697
698         if (result == PCI_ERS_RESULT_NONE ||
699                 result == PCI_ERS_RESULT_DISCONNECT) {
700                 dev_dbg(&dev->dev,
701                         "No AER slot_reset service or disconnected!\n");
702                 kill_domain_by_device(psdev);
703         }
704 end:
705         if (psdev)
706                 pcistub_device_put(psdev);
707         up_write(&pcistub_sem);
708         return result;
709
710 }
711
712
713 /*xen_pcibk_mmio_enabled: it will send the mmio_enabled request to  pcifront
714 * in case of the device driver could provide this service, and then wait
715 * for pcifront ack
716 * @dev: pointer to PCI devices
717 * return value is used by aer_core do_recovery policy
718 */
719
720 static pci_ers_result_t xen_pcibk_mmio_enabled(struct pci_dev *dev)
721 {
722         struct pcistub_device *psdev;
723         pci_ers_result_t result;
724
725         result = PCI_ERS_RESULT_RECOVERED;
726         dev_dbg(&dev->dev, "xen_pcibk_mmio_enabled(bus:%x,devfn:%x)\n",
727                 dev->bus->number, dev->devfn);
728
729         down_write(&pcistub_sem);
730         psdev = pcistub_device_find(pci_domain_nr(dev->bus),
731                                 dev->bus->number,
732                                 PCI_SLOT(dev->devfn),
733                                 PCI_FUNC(dev->devfn));
734
735         if (!psdev || !psdev->pdev) {
736                 dev_err(&dev->dev,
737                         DRV_NAME " device is not found/assigned\n");
738                 goto end;
739         }
740
741         if (!psdev->pdev->sh_info) {
742                 dev_err(&dev->dev, DRV_NAME " device is not connected or owned"
743                         " by HVM, kill it\n");
744                 kill_domain_by_device(psdev);
745                 goto end;
746         }
747
748         if (!test_bit(_XEN_PCIB_AERHANDLER,
749                 (unsigned long *)&psdev->pdev->sh_info->flags)) {
750                 dev_err(&dev->dev,
751                         "guest with no AER driver should have been killed\n");
752                 goto end;
753         }
754         result = common_process(psdev, 1, XEN_PCI_OP_aer_mmio, result);
755
756         if (result == PCI_ERS_RESULT_NONE ||
757                 result == PCI_ERS_RESULT_DISCONNECT) {
758                 dev_dbg(&dev->dev,
759                         "No AER mmio_enabled service or disconnected!\n");
760                 kill_domain_by_device(psdev);
761         }
762 end:
763         if (psdev)
764                 pcistub_device_put(psdev);
765         up_write(&pcistub_sem);
766         return result;
767 }
768
769 /*xen_pcibk_error_detected: it will send the error_detected request to  pcifront
770 * in case of the device driver could provide this service, and then wait
771 * for pcifront ack.
772 * @dev: pointer to PCI devices
773 * @error: the current PCI connection state
774 * return value is used by aer_core do_recovery policy
775 */
776
777 static pci_ers_result_t xen_pcibk_error_detected(struct pci_dev *dev,
778         pci_channel_state_t error)
779 {
780         struct pcistub_device *psdev;
781         pci_ers_result_t result;
782
783         result = PCI_ERS_RESULT_CAN_RECOVER;
784         dev_dbg(&dev->dev, "xen_pcibk_error_detected(bus:%x,devfn:%x)\n",
785                 dev->bus->number, dev->devfn);
786
787         down_write(&pcistub_sem);
788         psdev = pcistub_device_find(pci_domain_nr(dev->bus),
789                                 dev->bus->number,
790                                 PCI_SLOT(dev->devfn),
791                                 PCI_FUNC(dev->devfn));
792
793         if (!psdev || !psdev->pdev) {
794                 dev_err(&dev->dev,
795                         DRV_NAME " device is not found/assigned\n");
796                 goto end;
797         }
798
799         if (!psdev->pdev->sh_info) {
800                 dev_err(&dev->dev, DRV_NAME " device is not connected or owned"
801                         " by HVM, kill it\n");
802                 kill_domain_by_device(psdev);
803                 goto end;
804         }
805
806         /*Guest owns the device yet no aer handler regiested, kill guest*/
807         if (!test_bit(_XEN_PCIB_AERHANDLER,
808                 (unsigned long *)&psdev->pdev->sh_info->flags)) {
809                 dev_dbg(&dev->dev, "guest may have no aer driver, kill it\n");
810                 kill_domain_by_device(psdev);
811                 goto end;
812         }
813         result = common_process(psdev, error, XEN_PCI_OP_aer_detected, result);
814
815         if (result == PCI_ERS_RESULT_NONE ||
816                 result == PCI_ERS_RESULT_DISCONNECT) {
817                 dev_dbg(&dev->dev,
818                         "No AER error_detected service or disconnected!\n");
819                 kill_domain_by_device(psdev);
820         }
821 end:
822         if (psdev)
823                 pcistub_device_put(psdev);
824         up_write(&pcistub_sem);
825         return result;
826 }
827
828 /*xen_pcibk_error_resume: it will send the error_resume request to  pcifront
829 * in case of the device driver could provide this service, and then wait
830 * for pcifront ack.
831 * @dev: pointer to PCI devices
832 */
833
834 static void xen_pcibk_error_resume(struct pci_dev *dev)
835 {
836         struct pcistub_device *psdev;
837
838         dev_dbg(&dev->dev, "xen_pcibk_error_resume(bus:%x,devfn:%x)\n",
839                 dev->bus->number, dev->devfn);
840
841         down_write(&pcistub_sem);
842         psdev = pcistub_device_find(pci_domain_nr(dev->bus),
843                                 dev->bus->number,
844                                 PCI_SLOT(dev->devfn),
845                                 PCI_FUNC(dev->devfn));
846
847         if (!psdev || !psdev->pdev) {
848                 dev_err(&dev->dev,
849                         DRV_NAME " device is not found/assigned\n");
850                 goto end;
851         }
852
853         if (!psdev->pdev->sh_info) {
854                 dev_err(&dev->dev, DRV_NAME " device is not connected or owned"
855                         " by HVM, kill it\n");
856                 kill_domain_by_device(psdev);
857                 goto end;
858         }
859
860         if (!test_bit(_XEN_PCIB_AERHANDLER,
861                 (unsigned long *)&psdev->pdev->sh_info->flags)) {
862                 dev_err(&dev->dev,
863                         "guest with no AER driver should have been killed\n");
864                 kill_domain_by_device(psdev);
865                 goto end;
866         }
867         common_process(psdev, 1, XEN_PCI_OP_aer_resume,
868                        PCI_ERS_RESULT_RECOVERED);
869 end:
870         if (psdev)
871                 pcistub_device_put(psdev);
872         up_write(&pcistub_sem);
873         return;
874 }
875
876 /*add xen_pcibk AER handling*/
877 static const struct pci_error_handlers xen_pcibk_error_handler = {
878         .error_detected = xen_pcibk_error_detected,
879         .mmio_enabled = xen_pcibk_mmio_enabled,
880         .slot_reset = xen_pcibk_slot_reset,
881         .resume = xen_pcibk_error_resume,
882 };
883
884 /*
885  * Note: There is no MODULE_DEVICE_TABLE entry here because this isn't
886  * for a normal device. I don't want it to be loaded automatically.
887  */
888
889 static struct pci_driver xen_pcibk_pci_driver = {
890         /* The name should be xen_pciback, but until the tools are updated
891          * we will keep it as pciback. */
892         .name = "pciback",
893         .id_table = pcistub_ids,
894         .probe = pcistub_probe,
895         .remove = pcistub_remove,
896         .err_handler = &xen_pcibk_error_handler,
897 };
898
899 static inline int str_to_slot(const char *buf, int *domain, int *bus,
900                               int *slot, int *func)
901 {
902         int parsed = 0;
903
904         switch (sscanf(buf, " %x:%x:%x.%x %n", domain, bus, slot, func,
905                        &parsed)) {
906         case 3:
907                 *func = -1;
908                 sscanf(buf, " %x:%x:%x.* %n", domain, bus, slot, &parsed);
909                 break;
910         case 2:
911                 *slot = *func = -1;
912                 sscanf(buf, " %x:%x:*.* %n", domain, bus, &parsed);
913                 break;
914         }
915         if (parsed && !buf[parsed])
916                 return 0;
917
918         /* try again without domain */
919         *domain = 0;
920         switch (sscanf(buf, " %x:%x.%x %n", bus, slot, func, &parsed)) {
921         case 2:
922                 *func = -1;
923                 sscanf(buf, " %x:%x.* %n", bus, slot, &parsed);
924                 break;
925         case 1:
926                 *slot = *func = -1;
927                 sscanf(buf, " %x:*.* %n", bus, &parsed);
928                 break;
929         }
930         if (parsed && !buf[parsed])
931                 return 0;
932
933         return -EINVAL;
934 }
935
936 static inline int str_to_quirk(const char *buf, int *domain, int *bus, int
937                                *slot, int *func, int *reg, int *size, int *mask)
938 {
939         int parsed = 0;
940
941         sscanf(buf, " %x:%x:%x.%x-%x:%x:%x %n", domain, bus, slot, func,
942                reg, size, mask, &parsed);
943         if (parsed && !buf[parsed])
944                 return 0;
945
946         /* try again without domain */
947         *domain = 0;
948         sscanf(buf, " %x:%x.%x-%x:%x:%x %n", bus, slot, func, reg, size,
949                mask, &parsed);
950         if (parsed && !buf[parsed])
951                 return 0;
952
953         return -EINVAL;
954 }
955
956 static int pcistub_device_id_add(int domain, int bus, int slot, int func)
957 {
958         struct pcistub_device_id *pci_dev_id;
959         unsigned long flags;
960         int rc = 0, devfn = PCI_DEVFN(slot, func);
961
962         if (slot < 0) {
963                 for (slot = 0; !rc && slot < 32; ++slot)
964                         rc = pcistub_device_id_add(domain, bus, slot, func);
965                 return rc;
966         }
967
968         if (func < 0) {
969                 for (func = 0; !rc && func < 8; ++func)
970                         rc = pcistub_device_id_add(domain, bus, slot, func);
971                 return rc;
972         }
973
974         if ((
975 #if !defined(MODULE) /* pci_domains_supported is not being exported */ \
976     || !defined(CONFIG_PCI_DOMAINS)
977              !pci_domains_supported ? domain :
978 #endif
979              domain < 0 || domain > 0xffff)
980             || bus < 0 || bus > 0xff
981             || PCI_SLOT(devfn) != slot
982             || PCI_FUNC(devfn) != func)
983                 return -EINVAL;
984
985         pci_dev_id = kmalloc(sizeof(*pci_dev_id), GFP_KERNEL);
986         if (!pci_dev_id)
987                 return -ENOMEM;
988
989         pci_dev_id->domain = domain;
990         pci_dev_id->bus = bus;
991         pci_dev_id->devfn = devfn;
992
993         pr_debug(DRV_NAME ": wants to seize %04x:%02x:%02x.%d\n",
994                  domain, bus, slot, func);
995
996         spin_lock_irqsave(&device_ids_lock, flags);
997         list_add_tail(&pci_dev_id->slot_list, &pcistub_device_ids);
998         spin_unlock_irqrestore(&device_ids_lock, flags);
999
1000         return 0;
1001 }
1002
1003 static int pcistub_device_id_remove(int domain, int bus, int slot, int func)
1004 {
1005         struct pcistub_device_id *pci_dev_id, *t;
1006         int err = -ENOENT;
1007         unsigned long flags;
1008
1009         spin_lock_irqsave(&device_ids_lock, flags);
1010         list_for_each_entry_safe(pci_dev_id, t, &pcistub_device_ids,
1011                                  slot_list) {
1012                 if (pci_dev_id->domain == domain && pci_dev_id->bus == bus
1013                     && (slot < 0 || PCI_SLOT(pci_dev_id->devfn) == slot)
1014                     && (func < 0 || PCI_FUNC(pci_dev_id->devfn) == func)) {
1015                         /* Don't break; here because it's possible the same
1016                          * slot could be in the list more than once
1017                          */
1018                         list_del(&pci_dev_id->slot_list);
1019                         kfree(pci_dev_id);
1020
1021                         err = 0;
1022
1023                         pr_debug(DRV_NAME ": removed %04x:%02x:%02x.%d from "
1024                                  "seize list\n", domain, bus, slot, func);
1025                 }
1026         }
1027         spin_unlock_irqrestore(&device_ids_lock, flags);
1028
1029         return err;
1030 }
1031
1032 static int pcistub_reg_add(int domain, int bus, int slot, int func,
1033                            unsigned int reg, unsigned int size,
1034                            unsigned int mask)
1035 {
1036         int err = 0;
1037         struct pcistub_device *psdev;
1038         struct pci_dev *dev;
1039         struct config_field *field;
1040
1041         if (reg > 0xfff || (size < 4 && (mask >> (size * 8))))
1042                 return -EINVAL;
1043
1044         psdev = pcistub_device_find(domain, bus, slot, func);
1045         if (!psdev) {
1046                 err = -ENODEV;
1047                 goto out;
1048         }
1049         dev = psdev->dev;
1050
1051         field = kzalloc(sizeof(*field), GFP_ATOMIC);
1052         if (!field) {
1053                 err = -ENOMEM;
1054                 goto out;
1055         }
1056
1057         field->offset = reg;
1058         field->size = size;
1059         field->mask = mask;
1060         field->init = NULL;
1061         field->reset = NULL;
1062         field->release = NULL;
1063         field->clean = xen_pcibk_config_field_free;
1064
1065         err = xen_pcibk_config_quirks_add_field(dev, field);
1066         if (err)
1067                 kfree(field);
1068 out:
1069         if (psdev)
1070                 pcistub_device_put(psdev);
1071         return err;
1072 }
1073
1074 static ssize_t pcistub_slot_add(struct device_driver *drv, const char *buf,
1075                                 size_t count)
1076 {
1077         int domain, bus, slot, func;
1078         int err;
1079
1080         err = str_to_slot(buf, &domain, &bus, &slot, &func);
1081         if (err)
1082                 goto out;
1083
1084         err = pcistub_device_id_add(domain, bus, slot, func);
1085
1086 out:
1087         if (!err)
1088                 err = count;
1089         return err;
1090 }
1091 static DRIVER_ATTR(new_slot, S_IWUSR, NULL, pcistub_slot_add);
1092
1093 static ssize_t pcistub_slot_remove(struct device_driver *drv, const char *buf,
1094                                    size_t count)
1095 {
1096         int domain, bus, slot, func;
1097         int err;
1098
1099         err = str_to_slot(buf, &domain, &bus, &slot, &func);
1100         if (err)
1101                 goto out;
1102
1103         err = pcistub_device_id_remove(domain, bus, slot, func);
1104
1105 out:
1106         if (!err)
1107                 err = count;
1108         return err;
1109 }
1110 static DRIVER_ATTR(remove_slot, S_IWUSR, NULL, pcistub_slot_remove);
1111
1112 static ssize_t pcistub_slot_show(struct device_driver *drv, char *buf)
1113 {
1114         struct pcistub_device_id *pci_dev_id;
1115         size_t count = 0;
1116         unsigned long flags;
1117
1118         spin_lock_irqsave(&device_ids_lock, flags);
1119         list_for_each_entry(pci_dev_id, &pcistub_device_ids, slot_list) {
1120                 if (count >= PAGE_SIZE)
1121                         break;
1122
1123                 count += scnprintf(buf + count, PAGE_SIZE - count,
1124                                    "%04x:%02x:%02x.%d\n",
1125                                    pci_dev_id->domain, pci_dev_id->bus,
1126                                    PCI_SLOT(pci_dev_id->devfn),
1127                                    PCI_FUNC(pci_dev_id->devfn));
1128         }
1129         spin_unlock_irqrestore(&device_ids_lock, flags);
1130
1131         return count;
1132 }
1133 static DRIVER_ATTR(slots, S_IRUSR, pcistub_slot_show, NULL);
1134
1135 static ssize_t pcistub_irq_handler_show(struct device_driver *drv, char *buf)
1136 {
1137         struct pcistub_device *psdev;
1138         struct xen_pcibk_dev_data *dev_data;
1139         size_t count = 0;
1140         unsigned long flags;
1141
1142         spin_lock_irqsave(&pcistub_devices_lock, flags);
1143         list_for_each_entry(psdev, &pcistub_devices, dev_list) {
1144                 if (count >= PAGE_SIZE)
1145                         break;
1146                 if (!psdev->dev)
1147                         continue;
1148                 dev_data = pci_get_drvdata(psdev->dev);
1149                 if (!dev_data)
1150                         continue;
1151                 count +=
1152                     scnprintf(buf + count, PAGE_SIZE - count,
1153                               "%s:%s:%sing:%ld\n",
1154                               pci_name(psdev->dev),
1155                               dev_data->isr_on ? "on" : "off",
1156                               dev_data->ack_intr ? "ack" : "not ack",
1157                               dev_data->handled);
1158         }
1159         spin_unlock_irqrestore(&pcistub_devices_lock, flags);
1160         return count;
1161 }
1162 static DRIVER_ATTR(irq_handlers, S_IRUSR, pcistub_irq_handler_show, NULL);
1163
1164 static ssize_t pcistub_irq_handler_switch(struct device_driver *drv,
1165                                           const char *buf,
1166                                           size_t count)
1167 {
1168         struct pcistub_device *psdev;
1169         struct xen_pcibk_dev_data *dev_data;
1170         int domain, bus, slot, func;
1171         int err = -ENOENT;
1172
1173         err = str_to_slot(buf, &domain, &bus, &slot, &func);
1174         if (err)
1175                 return err;
1176
1177         psdev = pcistub_device_find(domain, bus, slot, func);
1178         if (!psdev)
1179                 goto out;
1180
1181         dev_data = pci_get_drvdata(psdev->dev);
1182         if (!dev_data)
1183                 goto out;
1184
1185         dev_dbg(&psdev->dev->dev, "%s fake irq handler: %d->%d\n",
1186                 dev_data->irq_name, dev_data->isr_on,
1187                 !dev_data->isr_on);
1188
1189         dev_data->isr_on = !(dev_data->isr_on);
1190         if (dev_data->isr_on)
1191                 dev_data->ack_intr = 1;
1192 out:
1193         if (psdev)
1194                 pcistub_device_put(psdev);
1195         if (!err)
1196                 err = count;
1197         return err;
1198 }
1199 static DRIVER_ATTR(irq_handler_state, S_IWUSR, NULL,
1200                    pcistub_irq_handler_switch);
1201
1202 static ssize_t pcistub_quirk_add(struct device_driver *drv, const char *buf,
1203                                  size_t count)
1204 {
1205         int domain, bus, slot, func, reg, size, mask;
1206         int err;
1207
1208         err = str_to_quirk(buf, &domain, &bus, &slot, &func, &reg, &size,
1209                            &mask);
1210         if (err)
1211                 goto out;
1212
1213         err = pcistub_reg_add(domain, bus, slot, func, reg, size, mask);
1214
1215 out:
1216         if (!err)
1217                 err = count;
1218         return err;
1219 }
1220
1221 static ssize_t pcistub_quirk_show(struct device_driver *drv, char *buf)
1222 {
1223         int count = 0;
1224         unsigned long flags;
1225         struct xen_pcibk_config_quirk *quirk;
1226         struct xen_pcibk_dev_data *dev_data;
1227         const struct config_field *field;
1228         const struct config_field_entry *cfg_entry;
1229
1230         spin_lock_irqsave(&device_ids_lock, flags);
1231         list_for_each_entry(quirk, &xen_pcibk_quirks, quirks_list) {
1232                 if (count >= PAGE_SIZE)
1233                         goto out;
1234
1235                 count += scnprintf(buf + count, PAGE_SIZE - count,
1236                                    "%02x:%02x.%01x\n\t%04x:%04x:%04x:%04x\n",
1237                                    quirk->pdev->bus->number,
1238                                    PCI_SLOT(quirk->pdev->devfn),
1239                                    PCI_FUNC(quirk->pdev->devfn),
1240                                    quirk->devid.vendor, quirk->devid.device,
1241                                    quirk->devid.subvendor,
1242                                    quirk->devid.subdevice);
1243
1244                 dev_data = pci_get_drvdata(quirk->pdev);
1245
1246                 list_for_each_entry(cfg_entry, &dev_data->config_fields, list) {
1247                         field = cfg_entry->field;
1248                         if (count >= PAGE_SIZE)
1249                                 goto out;
1250
1251                         count += scnprintf(buf + count, PAGE_SIZE - count,
1252                                            "\t\t%08x:%01x:%08x\n",
1253                                            cfg_entry->base_offset +
1254                                            field->offset, field->size,
1255                                            field->mask);
1256                 }
1257         }
1258
1259 out:
1260         spin_unlock_irqrestore(&device_ids_lock, flags);
1261
1262         return count;
1263 }
1264 static DRIVER_ATTR(quirks, S_IRUSR | S_IWUSR, pcistub_quirk_show,
1265                    pcistub_quirk_add);
1266
1267 static ssize_t permissive_add(struct device_driver *drv, const char *buf,
1268                               size_t count)
1269 {
1270         int domain, bus, slot, func;
1271         int err;
1272         struct pcistub_device *psdev;
1273         struct xen_pcibk_dev_data *dev_data;
1274
1275         err = str_to_slot(buf, &domain, &bus, &slot, &func);
1276         if (err)
1277                 goto out;
1278
1279         psdev = pcistub_device_find(domain, bus, slot, func);
1280         if (!psdev) {
1281                 err = -ENODEV;
1282                 goto out;
1283         }
1284
1285         dev_data = pci_get_drvdata(psdev->dev);
1286         /* the driver data for a device should never be null at this point */
1287         if (!dev_data) {
1288                 err = -ENXIO;
1289                 goto release;
1290         }
1291         if (!dev_data->permissive) {
1292                 dev_data->permissive = 1;
1293                 /* Let user know that what they're doing could be unsafe */
1294                 dev_warn(&psdev->dev->dev, "enabling permissive mode "
1295                          "configuration space accesses!\n");
1296                 dev_warn(&psdev->dev->dev,
1297                          "permissive mode is potentially unsafe!\n");
1298         }
1299 release:
1300         pcistub_device_put(psdev);
1301 out:
1302         if (!err)
1303                 err = count;
1304         return err;
1305 }
1306
1307 static ssize_t permissive_show(struct device_driver *drv, char *buf)
1308 {
1309         struct pcistub_device *psdev;
1310         struct xen_pcibk_dev_data *dev_data;
1311         size_t count = 0;
1312         unsigned long flags;
1313         spin_lock_irqsave(&pcistub_devices_lock, flags);
1314         list_for_each_entry(psdev, &pcistub_devices, dev_list) {
1315                 if (count >= PAGE_SIZE)
1316                         break;
1317                 if (!psdev->dev)
1318                         continue;
1319                 dev_data = pci_get_drvdata(psdev->dev);
1320                 if (!dev_data || !dev_data->permissive)
1321                         continue;
1322                 count +=
1323                     scnprintf(buf + count, PAGE_SIZE - count, "%s\n",
1324                               pci_name(psdev->dev));
1325         }
1326         spin_unlock_irqrestore(&pcistub_devices_lock, flags);
1327         return count;
1328 }
1329 static DRIVER_ATTR(permissive, S_IRUSR | S_IWUSR, permissive_show,
1330                    permissive_add);
1331
1332 static void pcistub_exit(void)
1333 {
1334         driver_remove_file(&xen_pcibk_pci_driver.driver, &driver_attr_new_slot);
1335         driver_remove_file(&xen_pcibk_pci_driver.driver,
1336                            &driver_attr_remove_slot);
1337         driver_remove_file(&xen_pcibk_pci_driver.driver, &driver_attr_slots);
1338         driver_remove_file(&xen_pcibk_pci_driver.driver, &driver_attr_quirks);
1339         driver_remove_file(&xen_pcibk_pci_driver.driver,
1340                            &driver_attr_permissive);
1341         driver_remove_file(&xen_pcibk_pci_driver.driver,
1342                            &driver_attr_irq_handlers);
1343         driver_remove_file(&xen_pcibk_pci_driver.driver,
1344                            &driver_attr_irq_handler_state);
1345         pci_unregister_driver(&xen_pcibk_pci_driver);
1346 }
1347
1348 static int __init pcistub_init(void)
1349 {
1350         int pos = 0;
1351         int err = 0;
1352         int domain, bus, slot, func;
1353         int parsed;
1354
1355         if (pci_devs_to_hide && *pci_devs_to_hide) {
1356                 do {
1357                         parsed = 0;
1358
1359                         err = sscanf(pci_devs_to_hide + pos,
1360                                      " (%x:%x:%x.%x) %n",
1361                                      &domain, &bus, &slot, &func, &parsed);
1362                         switch (err) {
1363                         case 3:
1364                                 func = -1;
1365                                 sscanf(pci_devs_to_hide + pos,
1366                                        " (%x:%x:%x.*) %n",
1367                                        &domain, &bus, &slot, &parsed);
1368                                 break;
1369                         case 2:
1370                                 slot = func = -1;
1371                                 sscanf(pci_devs_to_hide + pos,
1372                                        " (%x:%x:*.*) %n",
1373                                        &domain, &bus, &parsed);
1374                                 break;
1375                         }
1376
1377                         if (!parsed) {
1378                                 domain = 0;
1379                                 err = sscanf(pci_devs_to_hide + pos,
1380                                              " (%x:%x.%x) %n",
1381                                              &bus, &slot, &func, &parsed);
1382                                 switch (err) {
1383                                 case 2:
1384                                         func = -1;
1385                                         sscanf(pci_devs_to_hide + pos,
1386                                                " (%x:%x.*) %n",
1387                                                &bus, &slot, &parsed);
1388                                         break;
1389                                 case 1:
1390                                         slot = func = -1;
1391                                         sscanf(pci_devs_to_hide + pos,
1392                                                " (%x:*.*) %n",
1393                                                &bus, &parsed);
1394                                         break;
1395                                 }
1396                         }
1397
1398                         if (parsed <= 0)
1399                                 goto parse_error;
1400
1401                         err = pcistub_device_id_add(domain, bus, slot, func);
1402                         if (err)
1403                                 goto out;
1404
1405                         pos += parsed;
1406                 } while (pci_devs_to_hide[pos]);
1407         }
1408
1409         /* If we're the first PCI Device Driver to register, we're the
1410          * first one to get offered PCI devices as they become
1411          * available (and thus we can be the first to grab them)
1412          */
1413         err = pci_register_driver(&xen_pcibk_pci_driver);
1414         if (err < 0)
1415                 goto out;
1416
1417         err = driver_create_file(&xen_pcibk_pci_driver.driver,
1418                                  &driver_attr_new_slot);
1419         if (!err)
1420                 err = driver_create_file(&xen_pcibk_pci_driver.driver,
1421                                          &driver_attr_remove_slot);
1422         if (!err)
1423                 err = driver_create_file(&xen_pcibk_pci_driver.driver,
1424                                          &driver_attr_slots);
1425         if (!err)
1426                 err = driver_create_file(&xen_pcibk_pci_driver.driver,
1427                                          &driver_attr_quirks);
1428         if (!err)
1429                 err = driver_create_file(&xen_pcibk_pci_driver.driver,
1430                                          &driver_attr_permissive);
1431
1432         if (!err)
1433                 err = driver_create_file(&xen_pcibk_pci_driver.driver,
1434                                          &driver_attr_irq_handlers);
1435         if (!err)
1436                 err = driver_create_file(&xen_pcibk_pci_driver.driver,
1437                                         &driver_attr_irq_handler_state);
1438         if (err)
1439                 pcistub_exit();
1440
1441 out:
1442         return err;
1443
1444 parse_error:
1445         printk(KERN_ERR DRV_NAME ": Error parsing pci_devs_to_hide at \"%s\"\n",
1446                pci_devs_to_hide + pos);
1447         return -EINVAL;
1448 }
1449
1450 #ifndef MODULE
1451 /*
1452  * fs_initcall happens before device_initcall
1453  * so xen_pcibk *should* get called first (b/c we
1454  * want to suck up any device before other drivers
1455  * get a chance by being the first pci device
1456  * driver to register)
1457  */
1458 fs_initcall(pcistub_init);
1459 #endif
1460
1461 static int __init xen_pcibk_init(void)
1462 {
1463         int err;
1464
1465         if (!xen_initial_domain())
1466                 return -ENODEV;
1467
1468         err = xen_pcibk_config_init();
1469         if (err)
1470                 return err;
1471
1472 #ifdef MODULE
1473         err = pcistub_init();
1474         if (err < 0)
1475                 return err;
1476 #endif
1477
1478         pcistub_init_devices_late();
1479         err = xen_pcibk_xenbus_register();
1480         if (err)
1481                 pcistub_exit();
1482
1483         return err;
1484 }
1485
1486 static void __exit xen_pcibk_cleanup(void)
1487 {
1488         xen_pcibk_xenbus_unregister();
1489         pcistub_exit();
1490 }
1491
1492 module_init(xen_pcibk_init);
1493 module_exit(xen_pcibk_cleanup);
1494
1495 MODULE_LICENSE("Dual BSD/GPL");
1496 MODULE_ALIAS("xen-backend:pci");