1	/*
2	* PCI Stub Driver - Grabs devices in backend to be exported later
3	*
4	* Ryan Wilson <hap9@epoch.ncsc.mil>
5	* Chris Bookholt <hap10@epoch.ncsc.mil>
6	*/
7
8	#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
9	#define dev_fmt pr_fmt
10
11	#include <linux/module.h>
12	#include <linux/init.h>
13	#include <linux/rwsem.h>
14	#include <linux/list.h>
15	#include <linux/spinlock.h>
16	#include <linux/kref.h>
17	#include <linux/pci.h>
18	#include <linux/wait.h>
19	#include <linux/sched.h>
20	#include <linux/atomic.h>
21	#include <xen/events.h>
22	#include <xen/pci.h>
23	#include <xen/xen.h>
24	#include <asm/xen/hypervisor.h>
25	#include <xen/interface/physdev.h>
26	#include "pciback.h"
27	#include "conf_space.h"
28	#include "conf_space_quirks.h"
29
30	#define PCISTUB_DRIVER_NAME "pciback"
31
32	static char *pci_devs_to_hide;
33	wait_queue_head_t xen_pcibk_aer_wait_queue;
34	/*Add sem for sync AER handling and xen_pcibk remove/reconfigue ops,
35	* We want to avoid in middle of AER ops, xen_pcibk devices is being removed
36	*/
37	static DECLARE_RWSEM(pcistub_sem);
38	module_param_named(hide, pci_devs_to_hide, charp, 0444);
39
40	struct pcistub_device_id {
41	struct list_head slot_list;
42	int domain;
43	unsigned char bus;
44	unsigned int devfn;
45	};
46	static LIST_HEAD(pcistub_device_ids);
47	static DEFINE_SPINLOCK(device_ids_lock);
48
49	struct pcistub_device {
50	struct kref kref;
51	struct list_head dev_list;
52	spinlock_t lock;
53
54	struct pci_dev *dev;
55	struct xen_pcibk_device *pdev;/* non-NULL if struct pci_dev is in use */
56	};
57
58	/* Access to pcistub_devices & seized_devices lists and the initialize_devices
59	* flag must be locked with pcistub_devices_lock
60	*/
61	static DEFINE_SPINLOCK(pcistub_devices_lock);
62	static LIST_HEAD(pcistub_devices);
63
64	/* wait for device_initcall before initializing our devices
65	* (see pcistub_init_devices_late)
66	*/
67	static int initialize_devices;
68	static LIST_HEAD(seized_devices);
69
70	static struct pcistub_device *pcistub_device_alloc(struct pci_dev *dev)
71	{
72	struct pcistub_device *psdev;
73
74	dev_dbg(&dev->dev, "pcistub_device_alloc\n");
75
76	psdev = kzalloc(size: sizeof(*psdev), GFP_KERNEL);
77	if (!psdev)
78	return NULL;
79
80	psdev->dev = pci_dev_get(dev);
81	if (!psdev->dev) {
82	kfree(objp: psdev);
83	return NULL;
84	}
85
86	kref_init(kref: &psdev->kref);
87	spin_lock_init(&psdev->lock);
88
89	return psdev;
90	}
91
92	/* Don't call this directly as it's called by pcistub_device_put */
93	static void pcistub_device_release(struct kref *kref)
94	{
95	struct pcistub_device *psdev;
96	struct pci_dev *dev;
97	struct xen_pcibk_dev_data *dev_data;
98
99	psdev = container_of(kref, struct pcistub_device, kref);
100	dev = psdev->dev;
101	dev_data = pci_get_drvdata(pdev: dev);
102
103	dev_dbg(&dev->dev, "pcistub_device_release\n");
104
105	xen_unregister_device_domain_owner(dev);
106
107	/* Call the reset function which does not take lock as this
108	* is called from "unbind" which takes a device_lock mutex.
109	*/
110	__pci_reset_function_locked(dev);
111	if (dev_data &&
112	pci_load_and_free_saved_state(dev, state: &dev_data->pci_saved_state))
113	dev_info(&dev->dev, "Could not reload PCI state\n");
114	else
115	pci_restore_state(dev);
116
117	if (dev->msix_cap) {
118	struct physdev_pci_device ppdev = {
119	.seg = pci_domain_nr(bus: dev->bus),
120	.bus = dev->bus->number,
121	.devfn = dev->devfn
122	};
123	int err = HYPERVISOR_physdev_op(PHYSDEVOP_release_msix,
124	arg: &ppdev);
125
126	if (err && err != -ENOSYS)
127	dev_warn(&dev->dev, "MSI-X release failed (%d)\n",
128	err);
129	}
130
131	/* Disable the device */
132	xen_pcibk_reset_device(pdev: dev);
133
134	kfree(objp: dev_data);
135	pci_set_drvdata(pdev: dev, NULL);
136
137	/* Clean-up the device */
138	xen_pcibk_config_free_dyn_fields(dev);
139	xen_pcibk_config_free_dev(dev);
140
141	pci_clear_dev_assigned(pdev: dev);
142	pci_dev_put(dev);
143
144	kfree(objp: psdev);
145	}
146
147	static inline void pcistub_device_get(struct pcistub_device *psdev)
148	{
149	kref_get(kref: &psdev->kref);
150	}
151
152	static inline void pcistub_device_put(struct pcistub_device *psdev)
153	{
154	kref_put(kref: &psdev->kref, release: pcistub_device_release);
155	}
156
157	static struct pcistub_device *pcistub_device_find_locked(int domain, int bus,
158	int slot, int func)
159	{
160	struct pcistub_device *psdev;
161
162	list_for_each_entry(psdev, &pcistub_devices, dev_list) {
163	if (psdev->dev != NULL
164	&& domain == pci_domain_nr(bus: psdev->dev->bus)
165	&& bus == psdev->dev->bus->number
166	&& slot == PCI_SLOT(psdev->dev->devfn)
167	&& func == PCI_FUNC(psdev->dev->devfn)) {
168	return psdev;
169	}
170	}
171
172	return NULL;
173	}
174
175	static struct pcistub_device *pcistub_device_find(int domain, int bus,
176	int slot, int func)
177	{
178	struct pcistub_device *psdev;
179	unsigned long flags;
180
181	spin_lock_irqsave(&pcistub_devices_lock, flags);
182
183	psdev = pcistub_device_find_locked(domain, bus, slot, func);
184	if (psdev)
185	pcistub_device_get(psdev);
186
187	spin_unlock_irqrestore(lock: &pcistub_devices_lock, flags);
188	return psdev;
189	}
190
191	static struct pci_dev *pcistub_device_get_pci_dev(struct xen_pcibk_device *pdev,
192	struct pcistub_device *psdev)
193	{
194	struct pci_dev *pci_dev = NULL;
195	unsigned long flags;
196
197	spin_lock_irqsave(&psdev->lock, flags);
198	if (!psdev->pdev) {
199	psdev->pdev = pdev;
200	pci_dev = psdev->dev;
201	}
202	spin_unlock_irqrestore(lock: &psdev->lock, flags);
203
204	if (pci_dev)
205	pcistub_device_get(psdev);
206
207	return pci_dev;
208	}
209
210	struct pci_dev *pcistub_get_pci_dev_by_slot(struct xen_pcibk_device *pdev,
211	int domain, int bus,
212	int slot, int func)
213	{
214	struct pcistub_device *psdev;
215	struct pci_dev *found_dev = NULL;
216	unsigned long flags;
217
218	spin_lock_irqsave(&pcistub_devices_lock, flags);
219
220	psdev = pcistub_device_find_locked(domain, bus, slot, func);
221	if (psdev)
222	found_dev = pcistub_device_get_pci_dev(pdev, psdev);
223
224	spin_unlock_irqrestore(lock: &pcistub_devices_lock, flags);
225	return found_dev;
226	}
227
228	struct pci_dev *pcistub_get_pci_dev(struct xen_pcibk_device *pdev,
229	struct pci_dev *dev)
230	{
231	struct pcistub_device *psdev;
232	struct pci_dev *found_dev = NULL;
233	unsigned long flags;
234
235	spin_lock_irqsave(&pcistub_devices_lock, flags);
236
237	list_for_each_entry(psdev, &pcistub_devices, dev_list) {
238	if (psdev->dev == dev) {
239	found_dev = pcistub_device_get_pci_dev(pdev, psdev);
240	break;
241	}
242	}
243
244	spin_unlock_irqrestore(lock: &pcistub_devices_lock, flags);
245	return found_dev;
246	}
247
248	/*
249	* Called when:
250	* - XenBus state has been reconfigure (pci unplug). See xen_pcibk_remove_device
251	* - XenBus state has been disconnected (guest shutdown). See xen_pcibk_xenbus_remove
252	* - 'echo BDF > unbind' on pciback module with no guest attached. See pcistub_remove
253	* - 'echo BDF > unbind' with a guest still using it. See pcistub_remove
254	*
255	* As such we have to be careful.
256	*
257	* To make this easier, the caller has to hold the device lock.
258	*/
259	void pcistub_put_pci_dev(struct pci_dev *dev)
260	{
261	struct pcistub_device *psdev, *found_psdev = NULL;
262	unsigned long flags;
263	struct xen_pcibk_dev_data *dev_data;
264	int ret;
265
266	spin_lock_irqsave(&pcistub_devices_lock, flags);
267
268	list_for_each_entry(psdev, &pcistub_devices, dev_list) {
269	if (psdev->dev == dev) {
270	found_psdev = psdev;
271	break;
272	}
273	}
274
275	spin_unlock_irqrestore(lock: &pcistub_devices_lock, flags);
276	if (WARN_ON(!found_psdev))
277	return;
278
279	/*hold this lock for avoiding breaking link between
280	* pcistub and xen_pcibk when AER is in processing
281	*/
282	down_write(sem: &pcistub_sem);
283	/* Cleanup our device
284	* (so it's ready for the next domain)
285	*/
286	device_lock_assert(dev: &dev->dev);
287	__pci_reset_function_locked(dev);
288
289	dev_data = pci_get_drvdata(pdev: dev);
290	ret = pci_load_saved_state(dev, state: dev_data->pci_saved_state);
291	if (!ret) {
292	/*
293	* The usual sequence is pci_save_state & pci_restore_state
294	* but the guest might have messed the configuration space up.
295	* Use the initial version (when device was bound to us).
296	*/
297	pci_restore_state(dev);
298	} else
299	dev_info(&dev->dev, "Could not reload PCI state\n");
300	/* This disables the device. */
301	xen_pcibk_reset_device(pdev: dev);
302
303	/* And cleanup up our emulated fields. */
304	xen_pcibk_config_reset_dev(dev);
305	xen_pcibk_config_free_dyn_fields(dev);
306
307	dev_data->allow_interrupt_control = 0;
308
309	xen_unregister_device_domain_owner(dev);
310
311	spin_lock_irqsave(&found_psdev->lock, flags);
312	found_psdev->pdev = NULL;
313	spin_unlock_irqrestore(lock: &found_psdev->lock, flags);
314
315	pcistub_device_put(psdev: found_psdev);
316	up_write(sem: &pcistub_sem);
317	}
318
319	static int pcistub_match_one(struct pci_dev *dev,
320	struct pcistub_device_id *pdev_id)
321	{
322	/* Match the specified device by domain, bus, slot, func and also if
323	* any of the device's parent bridges match.
324	*/
325	for (; dev != NULL; dev = dev->bus->self) {
326	if (pci_domain_nr(bus: dev->bus) == pdev_id->domain
327	&& dev->bus->number == pdev_id->bus
328	&& dev->devfn == pdev_id->devfn)
329	return 1;
330
331	/* Sometimes topmost bridge links to itself. */
332	if (dev == dev->bus->self)
333	break;
334	}
335
336	return 0;
337	}
338
339	static int pcistub_match(struct pci_dev *dev)
340	{
341	struct pcistub_device_id *pdev_id;
342	unsigned long flags;
343	int found = 0;
344
345	spin_lock_irqsave(&device_ids_lock, flags);
346	list_for_each_entry(pdev_id, &pcistub_device_ids, slot_list) {
347	if (pcistub_match_one(dev, pdev_id)) {
348	found = 1;
349	break;
350	}
351	}
352	spin_unlock_irqrestore(lock: &device_ids_lock, flags);
353
354	return found;
355	}
356
357	static int pcistub_init_device(struct pci_dev *dev)
358	{
359	struct xen_pcibk_dev_data *dev_data;
360	int err = 0;
361
362	dev_dbg(&dev->dev, "initializing...\n");
363
364	/* The PCI backend is not intended to be a module (or to work with
365	* removable PCI devices (yet). If it were, xen_pcibk_config_free()
366	* would need to be called somewhere to free the memory allocated
367	* here and then to call kfree(pci_get_drvdata(psdev->dev)).
368	*/
369	dev_data = kzalloc(size: sizeof(*dev_data) + strlen(DRV_NAME "[]")
370	+ strlen(pci_name(dev)) + 1, GFP_KERNEL);
371	if (!dev_data) {
372	err = -ENOMEM;
373	goto out;
374	}
375	pci_set_drvdata(pdev: dev, data: dev_data);
376
377	/*
378	* Setup name for fake IRQ handler. It will only be enabled
379	* once the device is turned on by the guest.
380	*/
381	sprintf(buf: dev_data->irq_name, DRV_NAME "[%s]", pci_name(pdev: dev));
382
383	dev_dbg(&dev->dev, "initializing config\n");
384
385	init_waitqueue_head(&xen_pcibk_aer_wait_queue);
386	err = xen_pcibk_config_init_dev(dev);
387	if (err)
388	goto out;
389
390	/* HACK: Force device (& ACPI) to determine what IRQ it's on - we
391	* must do this here because pcibios_enable_device may specify
392	* the pci device's true irq (and possibly its other resources)
393	* if they differ from what's in the configuration space.
394	* This makes the assumption that the device's resources won't
395	* change after this point (otherwise this code may break!)
396	*/
397	dev_dbg(&dev->dev, "enabling device\n");
398	err = pci_enable_device(dev);
399	if (err)
400	goto config_release;
401
402	if (dev->msix_cap) {
403	struct physdev_pci_device ppdev = {
404	.seg = pci_domain_nr(bus: dev->bus),
405	.bus = dev->bus->number,
406	.devfn = dev->devfn
407	};
408
409	err = HYPERVISOR_physdev_op(PHYSDEVOP_prepare_msix, arg: &ppdev);
410	if (err && err != -ENOSYS)
411	dev_err(&dev->dev, "MSI-X preparation failed (%d)\n",
412	err);
413	}
414
415	/* We need the device active to save the state. */
416	dev_dbg(&dev->dev, "save state of device\n");
417	pci_save_state(dev);
418	dev_data->pci_saved_state = pci_store_saved_state(dev);
419	if (!dev_data->pci_saved_state)
420	dev_err(&dev->dev, "Could not store PCI conf saved state!\n");
421	else {
422	dev_dbg(&dev->dev, "resetting (FLR, D3, etc) the device\n");
423	__pci_reset_function_locked(dev);
424	pci_restore_state(dev);
425	}
426	/* Now disable the device (this also ensures some private device
427	* data is setup before we export)
428	*/
429	dev_dbg(&dev->dev, "reset device\n");
430	xen_pcibk_reset_device(pdev: dev);
431
432	pci_set_dev_assigned(pdev: dev);
433	return 0;
434
435	config_release:
436	xen_pcibk_config_free_dev(dev);
437
438	out:
439	pci_set_drvdata(pdev: dev, NULL);
440	kfree(objp: dev_data);
441	return err;
442	}
443
444	/*
445	* Because some initialization still happens on
446	* devices during fs_initcall, we need to defer
447	* full initialization of our devices until
448	* device_initcall.
449	*/
450	static int __init pcistub_init_devices_late(void)
451	{
452	struct pcistub_device *psdev;
453	unsigned long flags;
454	int err = 0;
455
456	spin_lock_irqsave(&pcistub_devices_lock, flags);
457
458	while (!list_empty(head: &seized_devices)) {
459	psdev = container_of(seized_devices.next,
460	struct pcistub_device, dev_list);
461	list_del(entry: &psdev->dev_list);
462
463	spin_unlock_irqrestore(lock: &pcistub_devices_lock, flags);
464
465	err = pcistub_init_device(dev: psdev->dev);
466	if (err) {
467	dev_err(&psdev->dev->dev,
468	"error %d initializing device\n", err);
469	kfree(objp: psdev);
470	psdev = NULL;
471	}
472
473	spin_lock_irqsave(&pcistub_devices_lock, flags);
474
475	if (psdev)
476	list_add_tail(new: &psdev->dev_list, head: &pcistub_devices);
477	}
478
479	initialize_devices = 1;
480
481	spin_unlock_irqrestore(lock: &pcistub_devices_lock, flags);
482
483	return 0;
484	}
485
486	static void pcistub_device_id_add_list(struct pcistub_device_id *new,
487	int domain, int bus, unsigned int devfn)
488	{
489	struct pcistub_device_id *pci_dev_id;
490	unsigned long flags;
491	int found = 0;
492
493	spin_lock_irqsave(&device_ids_lock, flags);
494
495	list_for_each_entry(pci_dev_id, &pcistub_device_ids, slot_list) {
496	if (pci_dev_id->domain == domain && pci_dev_id->bus == bus &&
497	pci_dev_id->devfn == devfn) {
498	found = 1;
499	break;
500	}
501	}
502
503	if (!found) {
504	new->domain = domain;
505	new->bus = bus;
506	new->devfn = devfn;
507	list_add_tail(new: &new->slot_list, head: &pcistub_device_ids);
508	}
509
510	spin_unlock_irqrestore(lock: &device_ids_lock, flags);
511
512	if (found)
513	kfree(objp: new);
514	}
515
516	static int pcistub_seize(struct pci_dev *dev,
517	struct pcistub_device_id *pci_dev_id)
518	{
519	struct pcistub_device *psdev;
520	unsigned long flags;
521	int err = 0;
522
523	psdev = pcistub_device_alloc(dev);
524	if (!psdev) {
525	kfree(objp: pci_dev_id);
526	return -ENOMEM;
527	}
528
529	spin_lock_irqsave(&pcistub_devices_lock, flags);
530
531	if (initialize_devices) {
532	spin_unlock_irqrestore(lock: &pcistub_devices_lock, flags);
533
534	/* don't want irqs disabled when calling pcistub_init_device */
535	err = pcistub_init_device(dev: psdev->dev);
536
537	spin_lock_irqsave(&pcistub_devices_lock, flags);
538
539	if (!err)
540	list_add(new: &psdev->dev_list, head: &pcistub_devices);
541	} else {
542	dev_dbg(&dev->dev, "deferring initialization\n");
543	list_add(new: &psdev->dev_list, head: &seized_devices);
544	}
545
546	spin_unlock_irqrestore(lock: &pcistub_devices_lock, flags);
547
548	if (err) {
549	kfree(objp: pci_dev_id);
550	pcistub_device_put(psdev);
551	} else if (pci_dev_id)
552	pcistub_device_id_add_list(new: pci_dev_id, domain: pci_domain_nr(bus: dev->bus),
553	bus: dev->bus->number, devfn: dev->devfn);
554
555	return err;
556	}
557
558	/* Called when 'bind'. This means we must _NOT_ call pci_reset_function or
559	* other functions that take the sysfs lock. */
560	static int pcistub_probe(struct pci_dev *dev, const struct pci_device_id *id)
561	{
562	int err = 0, match;
563	struct pcistub_device_id *pci_dev_id = NULL;
564
565	dev_dbg(&dev->dev, "probing...\n");
566
567	match = pcistub_match(dev);
568
569	if ((dev->driver_override &&
570	!strcmp(dev->driver_override, PCISTUB_DRIVER_NAME)) ||
571	match) {
572
573	if (dev->hdr_type != PCI_HEADER_TYPE_NORMAL
574	&& dev->hdr_type != PCI_HEADER_TYPE_BRIDGE) {
575	dev_err(&dev->dev, "can't export pci devices that "
576	"don't have a normal (0) or bridge (1) "
577	"header type!\n");
578	err = -ENODEV;
579	goto out;
580	}
581
582	if (!match) {
583	pci_dev_id = kmalloc(size: sizeof(*pci_dev_id), GFP_KERNEL);
584	if (!pci_dev_id) {
585	err = -ENOMEM;
586	goto out;
587	}
588	}
589
590	dev_info(&dev->dev, "seizing device\n");
591	err = pcistub_seize(dev, pci_dev_id);
592	} else
593	/* Didn't find the device */
594	err = -ENODEV;
595
596	out:
597	return err;
598	}
599
600	/* Called when 'unbind'. This means we must _NOT_ call pci_reset_function or
601	* other functions that take the sysfs lock. */
602	static void pcistub_remove(struct pci_dev *dev)
603	{
604	struct pcistub_device *psdev, *found_psdev = NULL;
605	unsigned long flags;
606
607	dev_dbg(&dev->dev, "removing\n");
608
609	spin_lock_irqsave(&pcistub_devices_lock, flags);
610
611	xen_pcibk_config_quirk_release(dev);
612
613	list_for_each_entry(psdev, &pcistub_devices, dev_list) {
614	if (psdev->dev == dev) {
615	found_psdev = psdev;
616	break;
617	}
618	}
619
620	spin_unlock_irqrestore(lock: &pcistub_devices_lock, flags);
621
622	if (found_psdev) {
623	dev_dbg(&dev->dev, "found device to remove %s\n",
624	found_psdev->pdev ? "- in-use" : "");
625
626	if (found_psdev->pdev) {
627	int domid = xen_find_device_domain_owner(dev);
628
629	dev_warn(&dev->dev, "****** removing device %s while still in-use by domain %d! ******\n",
630	pci_name(found_psdev->dev), domid);
631	dev_warn(&dev->dev, "****** driver domain may still access this device's i/o resources!\n");
632	dev_warn(&dev->dev, "****** shutdown driver domain before binding device\n");
633	dev_warn(&dev->dev, "****** to other drivers or domains\n");
634
635	/* N.B. This ends up calling pcistub_put_pci_dev which ends up
636	* doing the FLR. */
637	xen_pcibk_release_pci_dev(pdev: found_psdev->pdev,
638	dev: found_psdev->dev,
639	lock: false /* caller holds the lock. */);
640	}
641
642	spin_lock_irqsave(&pcistub_devices_lock, flags);
643	list_del(entry: &found_psdev->dev_list);
644	spin_unlock_irqrestore(lock: &pcistub_devices_lock, flags);
645
646	/* the final put for releasing from the list */
647	pcistub_device_put(psdev: found_psdev);
648	}
649	}
650
651	static const struct pci_device_id pcistub_ids[] = {
652	{
653	.vendor = PCI_ANY_ID,
654	.device = PCI_ANY_ID,
655	.subvendor = PCI_ANY_ID,
656	.subdevice = PCI_ANY_ID,
657	},
658	{0,},
659	};
660
661	#define PCI_NODENAME_MAX 40
662	static void kill_domain_by_device(struct pcistub_device *psdev)
663	{
664	struct xenbus_transaction xbt;
665	int err;
666	char nodename[PCI_NODENAME_MAX];
667
668	BUG_ON(!psdev);
669	snprintf(buf: nodename, PCI_NODENAME_MAX, fmt: "/local/domain/0/backend/pci/%d/0",
670	psdev->pdev->xdev->otherend_id);
671
672	again:
673	err = xenbus_transaction_start(t: &xbt);
674	if (err) {
675	dev_err(&psdev->dev->dev,
676	"error %d when start xenbus transaction\n", err);
677	return;
678	}
679	/*PV AER handlers will set this flag*/
680	xenbus_printf(t: xbt, dir: nodename, node: "aerState" , fmt: "aerfail");
681	err = xenbus_transaction_end(t: xbt, abort: 0);
682	if (err) {
683	if (err == -EAGAIN)
684	goto again;
685	dev_err(&psdev->dev->dev,
686	"error %d when end xenbus transaction\n", err);
687	return;
688	}
689	}
690
691	/* For each aer recovery step error_detected, mmio_enabled, etc, front_end and
692	* backend need to have cooperation. In xen_pcibk, those steps will do similar
693	* jobs: send service request and waiting for front_end response.
694	*/
695	static pci_ers_result_t common_process(struct pcistub_device *psdev,
696	pci_channel_state_t state, int aer_cmd,
697	pci_ers_result_t result)
698	{
699	pci_ers_result_t res = result;
700	struct xen_pcie_aer_op *aer_op;
701	struct xen_pcibk_device *pdev = psdev->pdev;
702	struct xen_pci_sharedinfo *sh_info = pdev->sh_info;
703	int ret;
704
705	/*with PV AER drivers*/
706	aer_op = &(sh_info->aer_op);
707	aer_op->cmd = aer_cmd ;
708	/*useful for error_detected callback*/
709	aer_op->err = state;
710	/*pcifront_end BDF*/
711	ret = xen_pcibk_get_pcifront_dev(pcidev: psdev->dev, pdev: psdev->pdev,
712	domain: &aer_op->domain, bus: &aer_op->bus, devfn: &aer_op->devfn);
713	if (!ret) {
714	dev_err(&psdev->dev->dev, "failed to get pcifront device\n");
715	return PCI_ERS_RESULT_NONE;
716	}
717	wmb();
718
719	dev_dbg(&psdev->dev->dev, "aer_op %x dom %x bus %x devfn %x\n",
720	aer_cmd, aer_op->domain, aer_op->bus, aer_op->devfn);
721	/*local flag to mark there's aer request, xen_pcibk callback will use
722	* this flag to judge whether we need to check pci-front give aer
723	* service ack signal
724	*/
725	set_bit(_PCIB_op_pending, addr: (unsigned long *)&pdev->flags);
726
727	/*It is possible that a pcifront conf_read_write ops request invokes
728	* the callback which cause the spurious execution of wake_up.
729	* Yet it is harmless and better than a spinlock here
730	*/
731	set_bit(_XEN_PCIB_active,
732	addr: (unsigned long *)&sh_info->flags);
733	wmb();
734	notify_remote_via_irq(irq: pdev->evtchn_irq);
735
736	/* Enable IRQ to signal "request done". */
737	xen_pcibk_lateeoi(pdev, eoi_flag: 0);
738
739	ret = wait_event_timeout(xen_pcibk_aer_wait_queue,
740	!(test_bit(_XEN_PCIB_active, (unsigned long *)
741	&sh_info->flags)), 300*HZ);
742
743	/* Enable IRQ for pcifront request if not already active. */
744	if (!test_bit(_PDEVF_op_active, &pdev->flags))
745	xen_pcibk_lateeoi(pdev, eoi_flag: 0);
746
747	if (!ret) {
748	if (test_bit(_XEN_PCIB_active,
749	(unsigned long *)&sh_info->flags)) {
750	dev_err(&psdev->dev->dev,
751	"pcifront aer process not responding!\n");
752	clear_bit(_XEN_PCIB_active,
753	addr: (unsigned long *)&sh_info->flags);
754	aer_op->err = PCI_ERS_RESULT_NONE;
755	return res;
756	}
757	}
758	clear_bit(_PCIB_op_pending, addr: (unsigned long *)&pdev->flags);
759
760	res = (pci_ers_result_t)aer_op->err;
761	return res;
762	}
763
764	/*
765	* xen_pcibk_slot_reset: it will send the slot_reset request to pcifront in case
766	* of the device driver could provide this service, and then wait for pcifront
767	* ack.
768	* @dev: pointer to PCI devices
769	* return value is used by aer_core do_recovery policy
770	*/
771	static pci_ers_result_t xen_pcibk_slot_reset(struct pci_dev *dev)
772	{
773	struct pcistub_device *psdev;
774	pci_ers_result_t result;
775
776	result = PCI_ERS_RESULT_RECOVERED;
777	dev_dbg(&dev->dev, "xen_pcibk_slot_reset(bus:%x,devfn:%x)\n",
778	dev->bus->number, dev->devfn);
779
780	down_write(sem: &pcistub_sem);
781	psdev = pcistub_device_find(domain: pci_domain_nr(bus: dev->bus),
782	bus: dev->bus->number,
783	PCI_SLOT(dev->devfn),
784	PCI_FUNC(dev->devfn));
785
786	if (!psdev || !psdev->pdev) {
787	dev_err(&dev->dev, "device is not found/assigned\n");
788	goto end;
789	}
790
791	if (!psdev->pdev->sh_info) {
792	dev_err(&dev->dev, "device is not connected or owned"
793	" by HVM, kill it\n");
794	kill_domain_by_device(psdev);
795	goto end;
796	}
797
798	if (!test_bit(_XEN_PCIB_AERHANDLER,
799	(unsigned long *)&psdev->pdev->sh_info->flags)) {
800	dev_err(&dev->dev,
801	"guest with no AER driver should have been killed\n");
802	goto end;
803	}
804	result = common_process(psdev, state: pci_channel_io_normal, XEN_PCI_OP_aer_slotreset, result);
805
806	if (result == PCI_ERS_RESULT_NONE ||
807	result == PCI_ERS_RESULT_DISCONNECT) {
808	dev_dbg(&dev->dev,
809	"No AER slot_reset service or disconnected!\n");
810	kill_domain_by_device(psdev);
811	}
812	end:
813	if (psdev)
814	pcistub_device_put(psdev);
815	up_write(sem: &pcistub_sem);
816	return result;
817
818	}
819
820
821	/*xen_pcibk_mmio_enabled: it will send the mmio_enabled request to pcifront
822	* in case of the device driver could provide this service, and then wait
823	* for pcifront ack
824	* @dev: pointer to PCI devices
825	* return value is used by aer_core do_recovery policy
826	*/
827
828	static pci_ers_result_t xen_pcibk_mmio_enabled(struct pci_dev *dev)
829	{
830	struct pcistub_device *psdev;
831	pci_ers_result_t result;
832
833	result = PCI_ERS_RESULT_RECOVERED;
834	dev_dbg(&dev->dev, "xen_pcibk_mmio_enabled(bus:%x,devfn:%x)\n",
835	dev->bus->number, dev->devfn);
836
837	down_write(sem: &pcistub_sem);
838	psdev = pcistub_device_find(domain: pci_domain_nr(bus: dev->bus),
839	bus: dev->bus->number,
840	PCI_SLOT(dev->devfn),
841	PCI_FUNC(dev->devfn));
842
843	if (!psdev || !psdev->pdev) {
844	dev_err(&dev->dev, "device is not found/assigned\n");
845	goto end;
846	}
847
848	if (!psdev->pdev->sh_info) {
849	dev_err(&dev->dev, "device is not connected or owned"
850	" by HVM, kill it\n");
851	kill_domain_by_device(psdev);
852	goto end;
853	}
854
855	if (!test_bit(_XEN_PCIB_AERHANDLER,
856	(unsigned long *)&psdev->pdev->sh_info->flags)) {
857	dev_err(&dev->dev,
858	"guest with no AER driver should have been killed\n");
859	goto end;
860	}
861	result = common_process(psdev, state: pci_channel_io_normal, XEN_PCI_OP_aer_mmio, result);
862
863	if (result == PCI_ERS_RESULT_NONE ||
864	result == PCI_ERS_RESULT_DISCONNECT) {
865	dev_dbg(&dev->dev,
866	"No AER mmio_enabled service or disconnected!\n");
867	kill_domain_by_device(psdev);
868	}
869	end:
870	if (psdev)
871	pcistub_device_put(psdev);
872	up_write(sem: &pcistub_sem);
873	return result;
874	}
875
876	/*xen_pcibk_error_detected: it will send the error_detected request to pcifront
877	* in case of the device driver could provide this service, and then wait
878	* for pcifront ack.
879	* @dev: pointer to PCI devices
880	* @error: the current PCI connection state
881	* return value is used by aer_core do_recovery policy
882	*/
883
884	static pci_ers_result_t xen_pcibk_error_detected(struct pci_dev *dev,
885	pci_channel_state_t error)
886	{
887	struct pcistub_device *psdev;
888	pci_ers_result_t result;
889
890	result = PCI_ERS_RESULT_CAN_RECOVER;
891	dev_dbg(&dev->dev, "xen_pcibk_error_detected(bus:%x,devfn:%x)\n",
892	dev->bus->number, dev->devfn);
893
894	down_write(sem: &pcistub_sem);
895	psdev = pcistub_device_find(domain: pci_domain_nr(bus: dev->bus),
896	bus: dev->bus->number,
897	PCI_SLOT(dev->devfn),
898	PCI_FUNC(dev->devfn));
899
900	if (!psdev || !psdev->pdev) {
901	dev_err(&dev->dev, "device is not found/assigned\n");
902	goto end;
903	}
904
905	if (!psdev->pdev->sh_info) {
906	dev_err(&dev->dev, "device is not connected or owned"
907	" by HVM, kill it\n");
908	kill_domain_by_device(psdev);
909	goto end;
910	}
911
912	/*Guest owns the device yet no aer handler regiested, kill guest*/
913	if (!test_bit(_XEN_PCIB_AERHANDLER,
914	(unsigned long *)&psdev->pdev->sh_info->flags)) {
915	dev_dbg(&dev->dev, "guest may have no aer driver, kill it\n");
916	kill_domain_by_device(psdev);
917	goto end;
918	}
919	result = common_process(psdev, state: error, XEN_PCI_OP_aer_detected, result);
920
921	if (result == PCI_ERS_RESULT_NONE ||
922	result == PCI_ERS_RESULT_DISCONNECT) {
923	dev_dbg(&dev->dev,
924	"No AER error_detected service or disconnected!\n");
925	kill_domain_by_device(psdev);
926	}
927	end:
928	if (psdev)
929	pcistub_device_put(psdev);
930	up_write(sem: &pcistub_sem);
931	return result;
932	}
933
934	/*xen_pcibk_error_resume: it will send the error_resume request to pcifront
935	* in case of the device driver could provide this service, and then wait
936	* for pcifront ack.
937	* @dev: pointer to PCI devices
938	*/
939
940	static void xen_pcibk_error_resume(struct pci_dev *dev)
941	{
942	struct pcistub_device *psdev;
943
944	dev_dbg(&dev->dev, "xen_pcibk_error_resume(bus:%x,devfn:%x)\n",
945	dev->bus->number, dev->devfn);
946
947	down_write(sem: &pcistub_sem);
948	psdev = pcistub_device_find(domain: pci_domain_nr(bus: dev->bus),
949	bus: dev->bus->number,
950	PCI_SLOT(dev->devfn),
951	PCI_FUNC(dev->devfn));
952
953	if (!psdev || !psdev->pdev) {
954	dev_err(&dev->dev, "device is not found/assigned\n");
955	goto end;
956	}
957
958	if (!psdev->pdev->sh_info) {
959	dev_err(&dev->dev, "device is not connected or owned"
960	" by HVM, kill it\n");
961	kill_domain_by_device(psdev);
962	goto end;
963	}
964
965	if (!test_bit(_XEN_PCIB_AERHANDLER,
966	(unsigned long *)&psdev->pdev->sh_info->flags)) {
967	dev_err(&dev->dev,
968	"guest with no AER driver should have been killed\n");
969	kill_domain_by_device(psdev);
970	goto end;
971	}
972	common_process(psdev, state: pci_channel_io_normal, XEN_PCI_OP_aer_resume,
973	result: PCI_ERS_RESULT_RECOVERED);
974	end:
975	if (psdev)
976	pcistub_device_put(psdev);
977	up_write(sem: &pcistub_sem);
978	return;
979	}
980
981	/*add xen_pcibk AER handling*/
982	static const struct pci_error_handlers xen_pcibk_error_handler = {
983	.error_detected = xen_pcibk_error_detected,
984	.mmio_enabled = xen_pcibk_mmio_enabled,
985	.slot_reset = xen_pcibk_slot_reset,
986	.resume = xen_pcibk_error_resume,
987	};
988
989	/*
990	* Note: There is no MODULE_DEVICE_TABLE entry here because this isn't
991	* for a normal device. I don't want it to be loaded automatically.
992	*/
993
994	static struct pci_driver xen_pcibk_pci_driver = {
995	/* The name should be xen_pciback, but until the tools are updated
996	* we will keep it as pciback. */
997	.name = PCISTUB_DRIVER_NAME,
998	.id_table = pcistub_ids,
999	.probe = pcistub_probe,
1000	.remove = pcistub_remove,
1001	.err_handler = &xen_pcibk_error_handler,
1002	};
1003
1004	static inline int str_to_slot(const char *buf, int *domain, int *bus,
1005	int *slot, int *func)
1006	{
1007	int parsed = 0;
1008
1009	switch (sscanf(buf, " %x:%x:%x.%x %n", domain, bus, slot, func,
1010	&parsed)) {
1011	case 3:
1012	*func = -1;
1013	sscanf(buf, " %x:%x:%x.* %n", domain, bus, slot, &parsed);
1014	break;
1015	case 2:
1016	*slot = *func = -1;
1017	sscanf(buf, " %x:%x:*.* %n", domain, bus, &parsed);
1018	break;
1019	}
1020	if (parsed && !buf[parsed])
1021	return 0;
1022
1023	/* try again without domain */
1024	*domain = 0;
1025	switch (sscanf(buf, " %x:%x.%x %n", bus, slot, func, &parsed)) {
1026	case 2:
1027	*func = -1;
1028	sscanf(buf, " %x:%x.* %n", bus, slot, &parsed);
1029	break;
1030	case 1:
1031	*slot = *func = -1;
1032	sscanf(buf, " %x:*.* %n", bus, &parsed);
1033	break;
1034	}
1035	if (parsed && !buf[parsed])
1036	return 0;
1037
1038	return -EINVAL;
1039	}
1040
1041	static inline int str_to_quirk(const char *buf, int *domain, int *bus, int
1042	*slot, int *func, int *reg, int *size, int *mask)
1043	{
1044	int parsed = 0;
1045
1046	sscanf(buf, " %x:%x:%x.%x-%x:%x:%x %n", domain, bus, slot, func,
1047	reg, size, mask, &parsed);
1048	if (parsed && !buf[parsed])
1049	return 0;
1050
1051	/* try again without domain */
1052	*domain = 0;
1053	sscanf(buf, " %x:%x.%x-%x:%x:%x %n", bus, slot, func, reg, size,
1054	mask, &parsed);
1055	if (parsed && !buf[parsed])
1056	return 0;
1057
1058	return -EINVAL;
1059	}
1060
1061	static int pcistub_device_id_add(int domain, int bus, int slot, int func)
1062	{
1063	struct pcistub_device_id *pci_dev_id;
1064	int rc = 0, devfn = PCI_DEVFN(slot, func);
1065
1066	if (slot < 0) {
1067	for (slot = 0; !rc && slot < 32; ++slot)
1068	rc = pcistub_device_id_add(domain, bus, slot, func);
1069	return rc;
1070	}
1071
1072	if (func < 0) {
1073	for (func = 0; !rc && func < 8; ++func)
1074	rc = pcistub_device_id_add(domain, bus, slot, func);
1075	return rc;
1076	}
1077
1078	if ((
1079	#if !defined(MODULE) /* pci_domains_supported is not being exported */ \
1080	|| !defined(CONFIG_PCI_DOMAINS)
1081	!pci_domains_supported ? domain :
1082	#endif
1083	domain < 0 || domain > 0xffff)
1084	|| bus < 0 || bus > 0xff
1085	|| PCI_SLOT(devfn) != slot
1086	|| PCI_FUNC(devfn) != func)
1087	return -EINVAL;
1088
1089	pci_dev_id = kmalloc(size: sizeof(*pci_dev_id), GFP_KERNEL);
1090	if (!pci_dev_id)
1091	return -ENOMEM;
1092
1093	pr_debug("wants to seize %04x:%02x:%02x.%d\n",
1094	domain, bus, slot, func);
1095
1096	pcistub_device_id_add_list(new: pci_dev_id, domain, bus, devfn);
1097
1098	return 0;
1099	}
1100
1101	static int pcistub_device_id_remove(int domain, int bus, int slot, int func)
1102	{
1103	struct pcistub_device_id *pci_dev_id, *t;
1104	int err = -ENOENT;
1105	unsigned long flags;
1106
1107	spin_lock_irqsave(&device_ids_lock, flags);
1108	list_for_each_entry_safe(pci_dev_id, t, &pcistub_device_ids,
1109	slot_list) {
1110	if (pci_dev_id->domain == domain && pci_dev_id->bus == bus
1111	&& (slot < 0 || PCI_SLOT(pci_dev_id->devfn) == slot)
1112	&& (func < 0 || PCI_FUNC(pci_dev_id->devfn) == func)) {
1113	/* Don't break; here because it's possible the same
1114	* slot could be in the list more than once
1115	*/
1116	list_del(entry: &pci_dev_id->slot_list);
1117	kfree(objp: pci_dev_id);
1118
1119	err = 0;
1120
1121	pr_debug("removed %04x:%02x:%02x.%d from seize list\n",
1122	domain, bus, slot, func);
1123	}
1124	}
1125	spin_unlock_irqrestore(lock: &device_ids_lock, flags);
1126
1127	return err;
1128	}
1129
1130	static int pcistub_reg_add(int domain, int bus, int slot, int func,
1131	unsigned int reg, unsigned int size,
1132	unsigned int mask)
1133	{
1134	int err = 0;
1135	struct pcistub_device *psdev;
1136	struct pci_dev *dev;
1137	struct config_field *field;
1138
1139	if (reg > 0xfff || (size < 4 && (mask >> (size * 8))))
1140	return -EINVAL;
1141
1142	psdev = pcistub_device_find(domain, bus, slot, func);
1143	if (!psdev) {
1144	err = -ENODEV;
1145	goto out;
1146	}
1147	dev = psdev->dev;
1148
1149	field = kzalloc(size: sizeof(*field), GFP_KERNEL);
1150	if (!field) {
1151	err = -ENOMEM;
1152	goto out;
1153	}
1154
1155	field->offset = reg;
1156	field->size = size;
1157	field->mask = mask;
1158	field->init = NULL;
1159	field->reset = NULL;
1160	field->release = NULL;
1161	field->clean = xen_pcibk_config_field_free;
1162
1163	err = xen_pcibk_config_quirks_add_field(dev, field);
1164	if (err)
1165	kfree(objp: field);
1166	out:
1167	if (psdev)
1168	pcistub_device_put(psdev);
1169	return err;
1170	}
1171
1172	static ssize_t new_slot_store(struct device_driver *drv, const char *buf,
1173	size_t count)
1174	{
1175	int domain, bus, slot, func;
1176	int err;
1177
1178	err = str_to_slot(buf, domain: &domain, bus: &bus, slot: &slot, func: &func);
1179	if (err)
1180	goto out;
1181
1182	err = pcistub_device_id_add(domain, bus, slot, func);
1183
1184	out:
1185	if (!err)
1186	err = count;
1187	return err;
1188	}
1189	static DRIVER_ATTR_WO(new_slot);
1190
1191	static ssize_t remove_slot_store(struct device_driver *drv, const char *buf,
1192	size_t count)
1193	{
1194	int domain, bus, slot, func;
1195	int err;
1196
1197	err = str_to_slot(buf, domain: &domain, bus: &bus, slot: &slot, func: &func);
1198	if (err)
1199	goto out;
1200
1201	err = pcistub_device_id_remove(domain, bus, slot, func);
1202
1203	out:
1204	if (!err)
1205	err = count;
1206	return err;
1207	}
1208	static DRIVER_ATTR_WO(remove_slot);
1209
1210	static ssize_t slots_show(struct device_driver *drv, char *buf)
1211	{
1212	struct pcistub_device_id *pci_dev_id;
1213	size_t count = 0;
1214	unsigned long flags;
1215
1216	spin_lock_irqsave(&device_ids_lock, flags);
1217	list_for_each_entry(pci_dev_id, &pcistub_device_ids, slot_list) {
1218	if (count >= PAGE_SIZE)
1219	break;
1220
1221	count += scnprintf(buf: buf + count, PAGE_SIZE - count,
1222	fmt: "%04x:%02x:%02x.%d\n",
1223	pci_dev_id->domain, pci_dev_id->bus,
1224	PCI_SLOT(pci_dev_id->devfn),
1225	PCI_FUNC(pci_dev_id->devfn));
1226	}
1227	spin_unlock_irqrestore(lock: &device_ids_lock, flags);
1228
1229	return count;
1230	}
1231	static DRIVER_ATTR_RO(slots);
1232
1233	static ssize_t irq_handlers_show(struct device_driver *drv, char *buf)
1234	{
1235	struct pcistub_device *psdev;
1236	struct xen_pcibk_dev_data *dev_data;
1237	size_t count = 0;
1238	unsigned long flags;
1239
1240	spin_lock_irqsave(&pcistub_devices_lock, flags);
1241	list_for_each_entry(psdev, &pcistub_devices, dev_list) {
1242	if (count >= PAGE_SIZE)
1243	break;
1244	if (!psdev->dev)
1245	continue;
1246	dev_data = pci_get_drvdata(pdev: psdev->dev);
1247	if (!dev_data)
1248	continue;
1249	count +=
1250	scnprintf(buf: buf + count, PAGE_SIZE - count,
1251	fmt: "%s:%s:%sing:%ld\n",
1252	pci_name(pdev: psdev->dev),
1253	dev_data->isr_on ? "on" : "off",
1254	dev_data->ack_intr ? "ack" : "not ack",
1255	dev_data->handled);
1256	}
1257	spin_unlock_irqrestore(lock: &pcistub_devices_lock, flags);
1258	return count;
1259	}
1260	static DRIVER_ATTR_RO(irq_handlers);
1261
1262	static ssize_t irq_handler_state_store(struct device_driver *drv,
1263	const char *buf, size_t count)
1264	{
1265	struct pcistub_device *psdev;
1266	struct xen_pcibk_dev_data *dev_data;
1267	int domain, bus, slot, func;
1268	int err;
1269
1270	err = str_to_slot(buf, domain: &domain, bus: &bus, slot: &slot, func: &func);
1271	if (err)
1272	return err;
1273
1274	psdev = pcistub_device_find(domain, bus, slot, func);
1275	if (!psdev) {
1276	err = -ENOENT;
1277	goto out;
1278	}
1279
1280	dev_data = pci_get_drvdata(pdev: psdev->dev);
1281	if (!dev_data) {
1282	err = -ENOENT;
1283	goto out;
1284	}
1285
1286	dev_dbg(&psdev->dev->dev, "%s fake irq handler: %d->%d\n",
1287	dev_data->irq_name, dev_data->isr_on,
1288	!dev_data->isr_on);
1289
1290	dev_data->isr_on = !(dev_data->isr_on);
1291	if (dev_data->isr_on)
1292	dev_data->ack_intr = 1;
1293	out:
1294	if (psdev)
1295	pcistub_device_put(psdev);
1296	if (!err)
1297	err = count;
1298	return err;
1299	}
1300	static DRIVER_ATTR_WO(irq_handler_state);
1301
1302	static ssize_t quirks_store(struct device_driver *drv, const char *buf,
1303	size_t count)
1304	{
1305	int domain, bus, slot, func, reg, size, mask;
1306	int err;
1307
1308	err = str_to_quirk(buf, domain: &domain, bus: &bus, slot: &slot, func: &func, reg: &reg, size: &size,
1309	mask: &mask);
1310	if (err)
1311	goto out;
1312
1313	err = pcistub_reg_add(domain, bus, slot, func, reg, size, mask);
1314
1315	out:
1316	if (!err)
1317	err = count;
1318	return err;
1319	}
1320
1321	static ssize_t quirks_show(struct device_driver *drv, char *buf)
1322	{
1323	int count = 0;
1324	unsigned long flags;
1325	struct xen_pcibk_config_quirk *quirk;
1326	struct xen_pcibk_dev_data *dev_data;
1327	const struct config_field *field;
1328	const struct config_field_entry *cfg_entry;
1329
1330	spin_lock_irqsave(&device_ids_lock, flags);
1331	list_for_each_entry(quirk, &xen_pcibk_quirks, quirks_list) {
1332	if (count >= PAGE_SIZE)
1333	goto out;
1334
1335	count += scnprintf(buf: buf + count, PAGE_SIZE - count,
1336	fmt: "%02x:%02x.%01x\n\t%04x:%04x:%04x:%04x\n",
1337	quirk->pdev->bus->number,
1338	PCI_SLOT(quirk->pdev->devfn),
1339	PCI_FUNC(quirk->pdev->devfn),
1340	quirk->devid.vendor, quirk->devid.device,
1341	quirk->devid.subvendor,
1342	quirk->devid.subdevice);
1343
1344	dev_data = pci_get_drvdata(pdev: quirk->pdev);
1345
1346	list_for_each_entry(cfg_entry, &dev_data->config_fields, list) {
1347	field = cfg_entry->field;
1348	if (count >= PAGE_SIZE)
1349	goto out;
1350
1351	count += scnprintf(buf: buf + count, PAGE_SIZE - count,
1352	fmt: "\t\t%08x:%01x:%08x\n",
1353	cfg_entry->base_offset +
1354	field->offset, field->size,
1355	field->mask);
1356	}
1357	}
1358
1359	out:
1360	spin_unlock_irqrestore(lock: &device_ids_lock, flags);
1361
1362	return count;
1363	}
1364	static DRIVER_ATTR_RW(quirks);
1365
1366	static ssize_t permissive_store(struct device_driver *drv, const char *buf,
1367	size_t count)
1368	{
1369	int domain, bus, slot, func;
1370	int err;
1371	struct pcistub_device *psdev;
1372	struct xen_pcibk_dev_data *dev_data;
1373
1374	err = str_to_slot(buf, domain: &domain, bus: &bus, slot: &slot, func: &func);
1375	if (err)
1376	goto out;
1377
1378	psdev = pcistub_device_find(domain, bus, slot, func);
1379	if (!psdev) {
1380	err = -ENODEV;
1381	goto out;
1382	}
1383
1384	dev_data = pci_get_drvdata(pdev: psdev->dev);
1385	/* the driver data for a device should never be null at this point */
1386	if (!dev_data) {
1387	err = -ENXIO;
1388	goto release;
1389	}
1390	if (!dev_data->permissive) {
1391	dev_data->permissive = 1;
1392	/* Let user know that what they're doing could be unsafe */
1393	dev_warn(&psdev->dev->dev, "enabling permissive mode "
1394	"configuration space accesses!\n");
1395	dev_warn(&psdev->dev->dev,
1396	"permissive mode is potentially unsafe!\n");
1397	}
1398	release:
1399	pcistub_device_put(psdev);
1400	out:
1401	if (!err)
1402	err = count;
1403	return err;
1404	}
1405
1406	static ssize_t permissive_show(struct device_driver *drv, char *buf)
1407	{
1408	struct pcistub_device *psdev;
1409	struct xen_pcibk_dev_data *dev_data;
1410	size_t count = 0;
1411	unsigned long flags;
1412	spin_lock_irqsave(&pcistub_devices_lock, flags);
1413	list_for_each_entry(psdev, &pcistub_devices, dev_list) {
1414	if (count >= PAGE_SIZE)
1415	break;
1416	if (!psdev->dev)
1417	continue;
1418	dev_data = pci_get_drvdata(pdev: psdev->dev);
1419	if (!dev_data || !dev_data->permissive)
1420	continue;
1421	count +=
1422	scnprintf(buf: buf + count, PAGE_SIZE - count, fmt: "%s\n",
1423	pci_name(pdev: psdev->dev));
1424	}
1425	spin_unlock_irqrestore(lock: &pcistub_devices_lock, flags);
1426	return count;
1427	}
1428	static DRIVER_ATTR_RW(permissive);
1429
1430	static ssize_t allow_interrupt_control_store(struct device_driver *drv,
1431	const char *buf, size_t count)
1432	{
1433	int domain, bus, slot, func;
1434	int err;
1435	struct pcistub_device *psdev;
1436	struct xen_pcibk_dev_data *dev_data;
1437
1438	err = str_to_slot(buf, domain: &domain, bus: &bus, slot: &slot, func: &func);
1439	if (err)
1440	goto out;
1441
1442	psdev = pcistub_device_find(domain, bus, slot, func);
1443	if (!psdev) {
1444	err = -ENODEV;
1445	goto out;
1446	}
1447
1448	dev_data = pci_get_drvdata(pdev: psdev->dev);
1449	/* the driver data for a device should never be null at this point */
1450	if (!dev_data) {
1451	err = -ENXIO;
1452	goto release;
1453	}
1454	dev_data->allow_interrupt_control = 1;
1455	release:
1456	pcistub_device_put(psdev);
1457	out:
1458	if (!err)
1459	err = count;
1460	return err;
1461	}
1462
1463	static ssize_t allow_interrupt_control_show(struct device_driver *drv,
1464	char *buf)
1465	{
1466	struct pcistub_device *psdev;
1467	struct xen_pcibk_dev_data *dev_data;
1468	size_t count = 0;
1469	unsigned long flags;
1470
1471	spin_lock_irqsave(&pcistub_devices_lock, flags);
1472	list_for_each_entry(psdev, &pcistub_devices, dev_list) {
1473	if (count >= PAGE_SIZE)
1474	break;
1475	if (!psdev->dev)
1476	continue;
1477	dev_data = pci_get_drvdata(pdev: psdev->dev);
1478	if (!dev_data || !dev_data->allow_interrupt_control)
1479	continue;
1480	count +=
1481	scnprintf(buf: buf + count, PAGE_SIZE - count, fmt: "%s\n",
1482	pci_name(pdev: psdev->dev));
1483	}
1484	spin_unlock_irqrestore(lock: &pcistub_devices_lock, flags);
1485	return count;
1486	}
1487	static DRIVER_ATTR_RW(allow_interrupt_control);
1488
1489	static void pcistub_exit(void)
1490	{
1491	driver_remove_file(driver: &xen_pcibk_pci_driver.driver, attr: &driver_attr_new_slot);
1492	driver_remove_file(driver: &xen_pcibk_pci_driver.driver,
1493	attr: &driver_attr_remove_slot);
1494	driver_remove_file(driver: &xen_pcibk_pci_driver.driver, attr: &driver_attr_slots);
1495	driver_remove_file(driver: &xen_pcibk_pci_driver.driver, attr: &driver_attr_quirks);
1496	driver_remove_file(driver: &xen_pcibk_pci_driver.driver,
1497	attr: &driver_attr_permissive);
1498	driver_remove_file(driver: &xen_pcibk_pci_driver.driver,
1499	attr: &driver_attr_allow_interrupt_control);
1500	driver_remove_file(driver: &xen_pcibk_pci_driver.driver,
1501	attr: &driver_attr_irq_handlers);
1502	driver_remove_file(driver: &xen_pcibk_pci_driver.driver,
1503	attr: &driver_attr_irq_handler_state);
1504	pci_unregister_driver(dev: &xen_pcibk_pci_driver);
1505	}
1506
1507	static int __init pcistub_init(void)
1508	{
1509	int pos = 0;
1510	int err = 0;
1511	int domain, bus, slot, func;
1512	int parsed;
1513
1514	if (pci_devs_to_hide && *pci_devs_to_hide) {
1515	do {
1516	parsed = 0;
1517
1518	err = sscanf(pci_devs_to_hide + pos,
1519	" (%x:%x:%x.%x) %n",
1520	&domain, &bus, &slot, &func, &parsed);
1521	switch (err) {
1522	case 3:
1523	func = -1;
1524	sscanf(pci_devs_to_hide + pos,
1525	" (%x:%x:%x.*) %n",
1526	&domain, &bus, &slot, &parsed);
1527	break;
1528	case 2:
1529	slot = func = -1;
1530	sscanf(pci_devs_to_hide + pos,
1531	" (%x:%x:*.*) %n",
1532	&domain, &bus, &parsed);
1533	break;
1534	}
1535
1536	if (!parsed) {
1537	domain = 0;
1538	err = sscanf(pci_devs_to_hide + pos,
1539	" (%x:%x.%x) %n",
1540	&bus, &slot, &func, &parsed);
1541	switch (err) {
1542	case 2:
1543	func = -1;
1544	sscanf(pci_devs_to_hide + pos,
1545	" (%x:%x.*) %n",
1546	&bus, &slot, &parsed);
1547	break;
1548	case 1:
1549	slot = func = -1;
1550	sscanf(pci_devs_to_hide + pos,
1551	" (%x:*.*) %n",
1552	&bus, &parsed);
1553	break;
1554	}
1555	}
1556
1557	if (parsed <= 0)
1558	goto parse_error;
1559
1560	err = pcistub_device_id_add(domain, bus, slot, func);
1561	if (err)
1562	goto out;
1563
1564	pos += parsed;
1565	} while (pci_devs_to_hide[pos]);
1566	}
1567
1568	/* If we're the first PCI Device Driver to register, we're the
1569	* first one to get offered PCI devices as they become
1570	* available (and thus we can be the first to grab them)
1571	*/
1572	err = pci_register_driver(&xen_pcibk_pci_driver);
1573	if (err < 0)
1574	goto out;
1575
1576	err = driver_create_file(driver: &xen_pcibk_pci_driver.driver,
1577	attr: &driver_attr_new_slot);
1578	if (!err)
1579	err = driver_create_file(driver: &xen_pcibk_pci_driver.driver,
1580	attr: &driver_attr_remove_slot);
1581	if (!err)
1582	err = driver_create_file(driver: &xen_pcibk_pci_driver.driver,
1583	attr: &driver_attr_slots);
1584	if (!err)
1585	err = driver_create_file(driver: &xen_pcibk_pci_driver.driver,
1586	attr: &driver_attr_quirks);
1587	if (!err)
1588	err = driver_create_file(driver: &xen_pcibk_pci_driver.driver,
1589	attr: &driver_attr_permissive);
1590	if (!err)
1591	err = driver_create_file(driver: &xen_pcibk_pci_driver.driver,
1592	attr: &driver_attr_allow_interrupt_control);
1593
1594	if (!err)
1595	err = driver_create_file(driver: &xen_pcibk_pci_driver.driver,
1596	attr: &driver_attr_irq_handlers);
1597	if (!err)
1598	err = driver_create_file(driver: &xen_pcibk_pci_driver.driver,
1599	attr: &driver_attr_irq_handler_state);
1600	if (err)
1601	pcistub_exit();
1602
1603	out:
1604	return err;
1605
1606	parse_error:
1607	pr_err("Error parsing pci_devs_to_hide at \"%s\"\n",
1608	pci_devs_to_hide + pos);
1609	return -EINVAL;
1610	}
1611
1612	#ifndef MODULE
1613	/*
1614	* fs_initcall happens before device_initcall
1615	* so xen_pcibk *should* get called first (b/c we
1616	* want to suck up any device before other drivers
1617	* get a chance by being the first pci device
1618	* driver to register)
1619	*/
1620	fs_initcall(pcistub_init);
1621	#endif
1622
1623	#ifdef CONFIG_PCI_IOV
1624	static struct pcistub_device *find_vfs(const struct pci_dev *pdev)
1625	{
1626	struct pcistub_device *psdev = NULL;
1627	unsigned long flags;
1628	bool found = false;
1629
1630	spin_lock_irqsave(&pcistub_devices_lock, flags);
1631	list_for_each_entry(psdev, &pcistub_devices, dev_list) {
1632	if (!psdev->pdev && psdev->dev != pdev
1633	&& pci_physfn(dev: psdev->dev) == pdev) {
1634	found = true;
1635	break;
1636	}
1637	}
1638	spin_unlock_irqrestore(lock: &pcistub_devices_lock, flags);
1639	if (found)
1640	return psdev;
1641	return NULL;
1642	}
1643
1644	static int pci_stub_notifier(struct notifier_block *nb,
1645	unsigned long action, void *data)
1646	{
1647	struct device *dev = data;
1648	const struct pci_dev *pdev = to_pci_dev(dev);
1649
1650	if (action != BUS_NOTIFY_UNBIND_DRIVER)
1651	return NOTIFY_DONE;
1652
1653	if (!pdev->is_physfn)
1654	return NOTIFY_DONE;
1655
1656	for (;;) {
1657	struct pcistub_device *psdev = find_vfs(pdev);
1658	if (!psdev)
1659	break;
1660	device_release_driver(dev: &psdev->dev->dev);
1661	}
1662	return NOTIFY_DONE;
1663	}
1664
1665	static struct notifier_block pci_stub_nb = {
1666	.notifier_call = pci_stub_notifier,
1667	};
1668	#endif
1669
1670	static int __init xen_pcibk_init(void)
1671	{
1672	int err;
1673
1674	if (!xen_initial_domain())
1675	return -ENODEV;
1676
1677	err = xen_pcibk_config_init();
1678	if (err)
1679	return err;
1680
1681	#ifdef MODULE
1682	err = pcistub_init();
1683	if (err < 0)
1684	return err;
1685	#endif
1686
1687	pcistub_init_devices_late();
1688	err = xen_pcibk_xenbus_register();
1689	if (err)
1690	pcistub_exit();
1691	#ifdef CONFIG_PCI_IOV
1692	else
1693	bus_register_notifier(bus: &pci_bus_type, nb: &pci_stub_nb);
1694	#endif
1695
1696	return err;
1697	}
1698
1699	static void __exit xen_pcibk_cleanup(void)
1700	{
1701	#ifdef CONFIG_PCI_IOV
1702	bus_unregister_notifier(bus: &pci_bus_type, nb: &pci_stub_nb);
1703	#endif
1704	xen_pcibk_xenbus_unregister();
1705	pcistub_exit();
1706	}
1707
1708	module_init(xen_pcibk_init);
1709	module_exit(xen_pcibk_cleanup);
1710
1711	MODULE_LICENSE("Dual BSD/GPL");
1712	MODULE_ALIAS("xen-backend:pci");
1713