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xen-pcifront: fix PCI reference leak
[net-next-2.6.git] / drivers / pci / xen-pcifront.c
CommitLineData
956a9202
RW		 1/*
2 * Xen PCI Frontend.
3 *
4 * Author: Ryan Wilson <hap9@epoch.ncsc.mil>
5 */
6#include <linux/module.h>
7#include <linux/init.h>
8#include <linux/mm.h>
9#include <xen/xenbus.h>
10#include <xen/events.h>
11#include <xen/grant_table.h>
12#include <xen/page.h>
13#include <linux/spinlock.h>
14#include <linux/pci.h>
15#include <linux/msi.h>
956a9202
RW		 16#include <xen/interface/io/pciif.h>
17#include <asm/xen/pci.h>
18#include <linux/interrupt.h>
19#include <asm/atomic.h>
20#include <linux/workqueue.h>
21#include <linux/bitops.h>
22#include <linux/time.h>
23
24#define INVALID_GRANT_REF (0)
25#define INVALID_EVTCHN (-1)
26
27struct pci_bus_entry {
28 struct list_head list;
29 struct pci_bus *bus;
30};
31
32#define _PDEVB_op_active (0)
33#define PDEVB_op_active (1 << (_PDEVB_op_active))
34
35struct pcifront_device {
36 struct xenbus_device *xdev;
37 struct list_head root_buses;
38
39 int evtchn;
40 int gnt_ref;
41
42 int irq;
43
44 /* Lock this when doing any operations in sh_info */
45 spinlock_t sh_info_lock;
46 struct xen_pci_sharedinfo *sh_info;
47 struct work_struct op_work;
48 unsigned long flags;
49
50};
51
52struct pcifront_sd {
53 int domain;
54 struct pcifront_device *pdev;
55};
56
57static inline struct pcifront_device *
58pcifront_get_pdev(struct pcifront_sd *sd)
59{
60 return sd->pdev;
61}
62
63static inline void pcifront_init_sd(struct pcifront_sd *sd,
64 unsigned int domain, unsigned int bus,
65 struct pcifront_device *pdev)
66{
67 sd->domain = domain;
68 sd->pdev = pdev;
69}
70
71static DEFINE_SPINLOCK(pcifront_dev_lock);
72static struct pcifront_device *pcifront_dev;
73
74static int verbose_request;
75module_param(verbose_request, int, 0644);
76
77static int errno_to_pcibios_err(int errno)
78{
79 switch (errno) {
80 case XEN_PCI_ERR_success:
81 return PCIBIOS_SUCCESSFUL;
82
83 case XEN_PCI_ERR_dev_not_found:
84 return PCIBIOS_DEVICE_NOT_FOUND;
85
86 case XEN_PCI_ERR_invalid_offset:
87 case XEN_PCI_ERR_op_failed:
88 return PCIBIOS_BAD_REGISTER_NUMBER;
89
90 case XEN_PCI_ERR_not_implemented:
91 return PCIBIOS_FUNC_NOT_SUPPORTED;
92
93 case XEN_PCI_ERR_access_denied:
94 return PCIBIOS_SET_FAILED;
95 }
96 return errno;
97}
98
99static inline void schedule_pcifront_aer_op(struct pcifront_device *pdev)
100{
101 if (test_bit(_XEN_PCIB_active, (unsigned long *)&pdev->sh_info->flags)
102 && !test_and_set_bit(_PDEVB_op_active, &pdev->flags)) {
103 dev_dbg(&pdev->xdev->dev, "schedule aer frontend job\n");
104 schedule_work(&pdev->op_work);
105 }
106}
107
108static int do_pci_op(struct pcifront_device *pdev, struct xen_pci_op *op)
109{
110 int err = 0;
111 struct xen_pci_op *active_op = &pdev->sh_info->op;
112 unsigned long irq_flags;
113 evtchn_port_t port = pdev->evtchn;
114 unsigned irq = pdev->irq;
115 s64 ns, ns_timeout;
116 struct timeval tv;
117
118 spin_lock_irqsave(&pdev->sh_info_lock, irq_flags);
119
120 memcpy(active_op, op, sizeof(struct xen_pci_op));
121
122 /* Go */
123 wmb();
124 set_bit(_XEN_PCIF_active, (unsigned long *)&pdev->sh_info->flags);
125 notify_remote_via_evtchn(port);
126
127 /*
128 * We set a poll timeout of 3 seconds but give up on return after
129 * 2 seconds. It is better to time out too late rather than too early
130 * (in the latter case we end up continually re-executing poll() with a
131 * timeout in the past). 1s difference gives plenty of slack for error.
132 */
133 do_gettimeofday(&tv);
134 ns_timeout = timeval_to_ns(&tv) + 2 * (s64)NSEC_PER_SEC;
135
136 xen_clear_irq_pending(irq);
137
138 while (test_bit(_XEN_PCIF_active,
139 (unsigned long *)&pdev->sh_info->flags)) {
140 xen_poll_irq_timeout(irq, jiffies + 3*HZ);
141 xen_clear_irq_pending(irq);
142 do_gettimeofday(&tv);
143 ns = timeval_to_ns(&tv);
144 if (ns > ns_timeout) {
145 dev_err(&pdev->xdev->dev,
146 "pciback not responding!!!\n");
147 clear_bit(_XEN_PCIF_active,
148 (unsigned long *)&pdev->sh_info->flags);
149 err = XEN_PCI_ERR_dev_not_found;
150 goto out;
151 }
152 }
153
154 /*
155 * We might lose backend service request since we
156 * reuse same evtchn with pci_conf backend response. So re-schedule
157 * aer pcifront service.
158 */
159 if (test_bit(_XEN_PCIB_active,
160 (unsigned long *)&pdev->sh_info->flags)) {
161 dev_err(&pdev->xdev->dev,
162 "schedule aer pcifront service\n");
163 schedule_pcifront_aer_op(pdev);
164 }
165
166 memcpy(op, active_op, sizeof(struct xen_pci_op));
167
168 err = op->err;
169out:
170 spin_unlock_irqrestore(&pdev->sh_info_lock, irq_flags);
171 return err;
172}
173
174/* Access to this function is spinlocked in drivers/pci/access.c */
175static int pcifront_bus_read(struct pci_bus *bus, unsigned int devfn,
176 int where, int size, u32 *val)
177{
178 int err = 0;
179 struct xen_pci_op op = {
180 .cmd = XEN_PCI_OP_conf_read,
181 .domain = pci_domain_nr(bus),
182 .bus = bus->number,
183 .devfn = devfn,
184 .offset = where,
185 .size = size,
186 };
187 struct pcifront_sd *sd = bus->sysdata;
188 struct pcifront_device *pdev = pcifront_get_pdev(sd);
189
190 if (verbose_request)
191 dev_info(&pdev->xdev->dev,
192 "read dev=%04x:%02x:%02x.%01x - offset %x size %d\n",
193 pci_domain_nr(bus), bus->number, PCI_SLOT(devfn),
194 PCI_FUNC(devfn), where, size);
195
196 err = do_pci_op(pdev, &op);
197
198 if (likely(!err)) {
199 if (verbose_request)
200 dev_info(&pdev->xdev->dev, "read got back value %x\n",
201 op.value);
202
203 *val = op.value;
204 } else if (err == -ENODEV) {
205 /* No device here, pretend that it just returned 0 */
206 err = 0;
207 *val = 0;
208 }
209
210 return errno_to_pcibios_err(err);
211}
212
213/* Access to this function is spinlocked in drivers/pci/access.c */
214static int pcifront_bus_write(struct pci_bus *bus, unsigned int devfn,
215 int where, int size, u32 val)
216{
217 struct xen_pci_op op = {
218 .cmd = XEN_PCI_OP_conf_write,
219 .domain = pci_domain_nr(bus),
220 .bus = bus->number,
221 .devfn = devfn,
222 .offset = where,
223 .size = size,
224 .value = val,
225 };
226 struct pcifront_sd *sd = bus->sysdata;
227 struct pcifront_device *pdev = pcifront_get_pdev(sd);
228
229 if (verbose_request)
230 dev_info(&pdev->xdev->dev,
231 "write dev=%04x:%02x:%02x.%01x - "
232 "offset %x size %d val %x\n",
233 pci_domain_nr(bus), bus->number,
234 PCI_SLOT(devfn), PCI_FUNC(devfn), where, size, val);
235
236 return errno_to_pcibios_err(do_pci_op(pdev, &op));
237}
238
239struct pci_ops pcifront_bus_ops = {
240 .read = pcifront_bus_read,
241 .write = pcifront_bus_write,
242};
243
244#ifdef CONFIG_PCI_MSI
245static int pci_frontend_enable_msix(struct pci_dev *dev,
246 int **vector, int nvec)
247{
248 int err;
249 int i;
250 struct xen_pci_op op = {
251 .cmd = XEN_PCI_OP_enable_msix,
252 .domain = pci_domain_nr(dev->bus),
253 .bus = dev->bus->number,
254 .devfn = dev->devfn,
255 .value = nvec,
256 };
257 struct pcifront_sd *sd = dev->bus->sysdata;
258 struct pcifront_device *pdev = pcifront_get_pdev(sd);
259 struct msi_desc *entry;
260
261 if (nvec > SH_INFO_MAX_VEC) {
262 dev_err(&dev->dev, "too much vector for pci frontend: %x."
263 " Increase SH_INFO_MAX_VEC.\n", nvec);
264 return -EINVAL;
265 }
266
267 i = 0;
268 list_for_each_entry(entry, &dev->msi_list, list) {
269 op.msix_entries[i].entry = entry->msi_attrib.entry_nr;
270 /* Vector is useless at this point. */
271 op.msix_entries[i].vector = -1;
272 i++;
273 }
274
275 err = do_pci_op(pdev, &op);
276
277 if (likely(!err)) {
278 if (likely(!op.value)) {
279 /* we get the result */
280 for (i = 0; i < nvec; i++)
281 *(*vector+i) = op.msix_entries[i].vector;
282 return 0;
283 } else {
284 printk(KERN_DEBUG "enable msix get value %x\n",
285 op.value);
286 return op.value;
287 }
288 } else {
289 dev_err(&dev->dev, "enable msix get err %x\n", err);
290 return err;
291 }
292}
293
294static void pci_frontend_disable_msix(struct pci_dev *dev)
295{
296 int err;
297 struct xen_pci_op op = {
298 .cmd = XEN_PCI_OP_disable_msix,
299 .domain = pci_domain_nr(dev->bus),
300 .bus = dev->bus->number,
301 .devfn = dev->devfn,
302 };
303 struct pcifront_sd *sd = dev->bus->sysdata;
304 struct pcifront_device *pdev = pcifront_get_pdev(sd);
305
306 err = do_pci_op(pdev, &op);
307
308 /* What should do for error ? */
309 if (err)
310 dev_err(&dev->dev, "pci_disable_msix get err %x\n", err);
311}
312
313static int pci_frontend_enable_msi(struct pci_dev *dev, int **vector)
314{
315 int err;
316 struct xen_pci_op op = {
317 .cmd = XEN_PCI_OP_enable_msi,
318 .domain = pci_domain_nr(dev->bus),
319 .bus = dev->bus->number,
320 .devfn = dev->devfn,
321 };
322 struct pcifront_sd *sd = dev->bus->sysdata;
323 struct pcifront_device *pdev = pcifront_get_pdev(sd);
324
325 err = do_pci_op(pdev, &op);
326 if (likely(!err)) {
327 *(*vector) = op.value;
328 } else {
329 dev_err(&dev->dev, "pci frontend enable msi failed for dev "
330 "%x:%x\n", op.bus, op.devfn);
331 err = -EINVAL;
332 }
333 return err;
334}
335
336static void pci_frontend_disable_msi(struct pci_dev *dev)
337{
338 int err;
339 struct xen_pci_op op = {
340 .cmd = XEN_PCI_OP_disable_msi,
341 .domain = pci_domain_nr(dev->bus),
342 .bus = dev->bus->number,
343 .devfn = dev->devfn,
344 };
345 struct pcifront_sd *sd = dev->bus->sysdata;
346 struct pcifront_device *pdev = pcifront_get_pdev(sd);
347
348 err = do_pci_op(pdev, &op);
349 if (err == XEN_PCI_ERR_dev_not_found) {
350 /* XXX No response from backend, what shall we do? */
351 printk(KERN_DEBUG "get no response from backend for disable MSI\n");
352 return;
353 }
354 if (err)
355 /* how can pciback notify us fail? */
356 printk(KERN_DEBUG "get fake response frombackend\n");
357}
358
359static struct xen_pci_frontend_ops pci_frontend_ops = {
360 .enable_msi = pci_frontend_enable_msi,
361 .disable_msi = pci_frontend_disable_msi,
362 .enable_msix = pci_frontend_enable_msix,
363 .disable_msix = pci_frontend_disable_msix,
364};
365
366static void pci_frontend_registrar(int enable)
367{
368 if (enable)
369 xen_pci_frontend = &pci_frontend_ops;
370 else
371 xen_pci_frontend = NULL;
372};
373#else
374static inline void pci_frontend_registrar(int enable) { };
375#endif /* CONFIG_PCI_MSI */
376
377/* Claim resources for the PCI frontend as-is, backend won't allow changes */
378static int pcifront_claim_resource(struct pci_dev *dev, void *data)
379{
380 struct pcifront_device *pdev = data;
381 int i;
382 struct resource *r;
383
384 for (i = 0; i < PCI_NUM_RESOURCES; i++) {
385 r = &dev->resource[i];
386
387 if (!r->parent && r->start && r->flags) {
388 dev_info(&pdev->xdev->dev, "claiming resource %s/%d\n",
389 pci_name(dev), i);
390 if (pci_claim_resource(dev, i)) {
391 dev_err(&pdev->xdev->dev, "Could not claim "
392 "resource %s/%d! Device offline. Try "
393 "giving less than 4GB to domain.\n",
394 pci_name(dev), i);
395 }
396 }
397 }
398
399 return 0;
400}
401
402static int __devinit pcifront_scan_bus(struct pcifront_device *pdev,
403 unsigned int domain, unsigned int bus,
404 struct pci_bus *b)
405{
406 struct pci_dev *d;
407 unsigned int devfn;
408
409 /* Scan the bus for functions and add.
410 * We omit handling of PCI bridge attachment because pciback prevents
411 * bridges from being exported.
412 */
413 for (devfn = 0; devfn < 0x100; devfn++) {
414 d = pci_get_slot(b, devfn);
415 if (d) {
416 /* Device is already known. */
417 pci_dev_put(d);
418 continue;
419 }
420
421 d = pci_scan_single_device(b, devfn);
422 if (d)
423 dev_info(&pdev->xdev->dev, "New device on "
424 "%04x:%02x:%02x.%02x found.\n", domain, bus,
425 PCI_SLOT(devfn), PCI_FUNC(devfn));
426 }
427
428 return 0;
429}
430
431static int __devinit pcifront_scan_root(struct pcifront_device *pdev,
432 unsigned int domain, unsigned int bus)
433{
434 struct pci_bus *b;
435 struct pcifront_sd *sd = NULL;
436 struct pci_bus_entry *bus_entry = NULL;
437 int err = 0;
438
439#ifndef CONFIG_PCI_DOMAINS
440 if (domain != 0) {
441 dev_err(&pdev->xdev->dev,
442 "PCI Root in non-zero PCI Domain! domain=%d\n", domain);
443 dev_err(&pdev->xdev->dev,
444 "Please compile with CONFIG_PCI_DOMAINS\n");
445 err = -EINVAL;
446 goto err_out;
447 }
448#endif
449
450 dev_info(&pdev->xdev->dev, "Creating PCI Frontend Bus %04x:%02x\n",
451 domain, bus);
452
453 bus_entry = kmalloc(sizeof(*bus_entry), GFP_KERNEL);
454 sd = kmalloc(sizeof(*sd), GFP_KERNEL);
455 if (!bus_entry || !sd) {
456 err = -ENOMEM;
457 goto err_out;
458 }
459 pcifront_init_sd(sd, domain, bus, pdev);
460
461 b = pci_scan_bus_parented(&pdev->xdev->dev, bus,
462 &pcifront_bus_ops, sd);
463 if (!b) {
464 dev_err(&pdev->xdev->dev,
465 "Error creating PCI Frontend Bus!\n");
466 err = -ENOMEM;
467 goto err_out;
468 }
469
470 bus_entry->bus = b;
471
472 list_add(&bus_entry->list, &pdev->root_buses);
473
474 /* pci_scan_bus_parented skips devices which do not have a have
475 * devfn==0. The pcifront_scan_bus enumerates all devfn. */
476 err = pcifront_scan_bus(pdev, domain, bus, b);
477
478 /* Claim resources before going "live" with our devices */
479 pci_walk_bus(b, pcifront_claim_resource, pdev);
480
481 /* Create SysFS and notify udev of the devices. Aka: "going live" */
482 pci_bus_add_devices(b);
483
484 return err;
485
486err_out:
487 kfree(bus_entry);
488 kfree(sd);
489
490 return err;
491}
492
493static int __devinit pcifront_rescan_root(struct pcifront_device *pdev,
494 unsigned int domain, unsigned int bus)
495{
496 int err;
497 struct pci_bus *b;
498
499#ifndef CONFIG_PCI_DOMAINS
500 if (domain != 0) {
501 dev_err(&pdev->xdev->dev,
502 "PCI Root in non-zero PCI Domain! domain=%d\n", domain);
503 dev_err(&pdev->xdev->dev,
504 "Please compile with CONFIG_PCI_DOMAINS\n");
505 return -EINVAL;
506 }
507#endif
508
509 dev_info(&pdev->xdev->dev, "Rescanning PCI Frontend Bus %04x:%02x\n",
510 domain, bus);
511
512 b = pci_find_bus(domain, bus);
513 if (!b)
514 /* If the bus is unknown, create it. */
515 return pcifront_scan_root(pdev, domain, bus);
516
517 err = pcifront_scan_bus(pdev, domain, bus, b);
518
519 /* Claim resources before going "live" with our devices */
520 pci_walk_bus(b, pcifront_claim_resource, pdev);
521
522 /* Create SysFS and notify udev of the devices. Aka: "going live" */
523 pci_bus_add_devices(b);
524
525 return err;
526}
527
528static void free_root_bus_devs(struct pci_bus *bus)
529{
530 struct pci_dev *dev;
531
532 while (!list_empty(&bus->devices)) {
533 dev = container_of(bus->devices.next, struct pci_dev,
534 bus_list);
535 dev_dbg(&dev->dev, "removing device\n");
536 pci_remove_bus_device(dev);
537 }
538}
539
540static void pcifront_free_roots(struct pcifront_device *pdev)
541{
542 struct pci_bus_entry *bus_entry, *t;
543
544 dev_dbg(&pdev->xdev->dev, "cleaning up root buses\n");
545
546 list_for_each_entry_safe(bus_entry, t, &pdev->root_buses, list) {
547 list_del(&bus_entry->list);
548
549 free_root_bus_devs(bus_entry->bus);
550
551 kfree(bus_entry->bus->sysdata);
552
553 device_unregister(bus_entry->bus->bridge);
554 pci_remove_bus(bus_entry->bus);
555
556 kfree(bus_entry);
557 }
558}
559
560static pci_ers_result_t pcifront_common_process(int cmd,
561 struct pcifront_device *pdev,
562 pci_channel_state_t state)
563{
564 pci_ers_result_t result;
565 struct pci_driver *pdrv;
566 int bus = pdev->sh_info->aer_op.bus;
567 int devfn = pdev->sh_info->aer_op.devfn;
568 struct pci_dev *pcidev;
569 int flag = 0;
570
571 dev_dbg(&pdev->xdev->dev,
572 "pcifront AER process: cmd %x (bus:%x, devfn%x)",
573 cmd, bus, devfn);
574 result = PCI_ERS_RESULT_NONE;
575
576 pcidev = pci_get_bus_and_slot(bus, devfn);
577 if (!pcidev || !pcidev->driver) {
2a63dd72
JS		 578 dev_err(&pdev->xdev->dev, "device or AER driver is NULL\n");
579 if (pcidev)
580 pci_dev_put(pcidev);
956a9202
RW		 581 return result;
582 }
583 pdrv = pcidev->driver;
584
585 if (get_driver(&pdrv->driver)) {
586 if (pdrv->err_handler && pdrv->err_handler->error_detected) {
587 dev_dbg(&pcidev->dev,
588 "trying to call AER service\n");
589 if (pcidev) {
590 flag = 1;
591 switch (cmd) {
592 case XEN_PCI_OP_aer_detected:
593 result = pdrv->err_handler->
594 error_detected(pcidev, state);
595 break;
596 case XEN_PCI_OP_aer_mmio:
597 result = pdrv->err_handler->
598 mmio_enabled(pcidev);
599 break;
600 case XEN_PCI_OP_aer_slotreset:
601 result = pdrv->err_handler->
602 slot_reset(pcidev);
603 break;
604 case XEN_PCI_OP_aer_resume:
605 pdrv->err_handler->resume(pcidev);
606 break;
607 default:
608 dev_err(&pdev->xdev->dev,
609 "bad request in aer recovery "
610 "operation!\n");
611
612 }
613 }
614 }
615 put_driver(&pdrv->driver);
616 }
617 if (!flag)
618 result = PCI_ERS_RESULT_NONE;
619
620 return result;
621}
622
623
624static void pcifront_do_aer(struct work_struct *data)
625{
626 struct pcifront_device *pdev =
627 container_of(data, struct pcifront_device, op_work);
628 int cmd = pdev->sh_info->aer_op.cmd;
629 pci_channel_state_t state =
630 (pci_channel_state_t)pdev->sh_info->aer_op.err;
631
632 /*If a pci_conf op is in progress,
633 we have to wait until it is done before service aer op*/
634 dev_dbg(&pdev->xdev->dev,
635 "pcifront service aer bus %x devfn %x\n",
636 pdev->sh_info->aer_op.bus, pdev->sh_info->aer_op.devfn);
637
638 pdev->sh_info->aer_op.err = pcifront_common_process(cmd, pdev, state);
639
640 /* Post the operation to the guest. */
641 wmb();
642 clear_bit(_XEN_PCIB_active, (unsigned long *)&pdev->sh_info->flags);
643 notify_remote_via_evtchn(pdev->evtchn);
644
645 /*in case of we lost an aer request in four lines time_window*/
646 smp_mb__before_clear_bit();
647 clear_bit(_PDEVB_op_active, &pdev->flags);
648 smp_mb__after_clear_bit();
649
650 schedule_pcifront_aer_op(pdev);
651
652}
653
654static irqreturn_t pcifront_handler_aer(int irq, void *dev)
655{
656 struct pcifront_device *pdev = dev;
657 schedule_pcifront_aer_op(pdev);
658 return IRQ_HANDLED;
659}
660static int pcifront_connect(struct pcifront_device *pdev)
661{
662 int err = 0;
663
664 spin_lock(&pcifront_dev_lock);
665
666 if (!pcifront_dev) {
667 dev_info(&pdev->xdev->dev, "Installing PCI frontend\n");
668 pcifront_dev = pdev;
669 } else {
670 dev_err(&pdev->xdev->dev, "PCI frontend already installed!\n");
671 err = -EEXIST;
672 }
673
674 spin_unlock(&pcifront_dev_lock);
675
676 return err;
677}
678
679static void pcifront_disconnect(struct pcifront_device *pdev)
680{
681 spin_lock(&pcifront_dev_lock);
682
683 if (pdev == pcifront_dev) {
684 dev_info(&pdev->xdev->dev,
685 "Disconnecting PCI Frontend Buses\n");
686 pcifront_dev = NULL;
687 }
688
689 spin_unlock(&pcifront_dev_lock);
690}
691static struct pcifront_device *alloc_pdev(struct xenbus_device *xdev)
692{
693 struct pcifront_device *pdev;
694
695 pdev = kzalloc(sizeof(struct pcifront_device), GFP_KERNEL);
696 if (pdev == NULL)
697 goto out;
698
699 pdev->sh_info =
700 (struct xen_pci_sharedinfo *)__get_free_page(GFP_KERNEL);
701 if (pdev->sh_info == NULL) {
702 kfree(pdev);
703 pdev = NULL;
704 goto out;
705 }
706 pdev->sh_info->flags = 0;
707
708 /*Flag for registering PV AER handler*/
709 set_bit(_XEN_PCIB_AERHANDLER, (void *)&pdev->sh_info->flags);
710
711 dev_set_drvdata(&xdev->dev, pdev);
712 pdev->xdev = xdev;
713
714 INIT_LIST_HEAD(&pdev->root_buses);
715
716 spin_lock_init(&pdev->sh_info_lock);
717
718 pdev->evtchn = INVALID_EVTCHN;
719 pdev->gnt_ref = INVALID_GRANT_REF;
720 pdev->irq = -1;
721
722 INIT_WORK(&pdev->op_work, pcifront_do_aer);
723
724 dev_dbg(&xdev->dev, "Allocated pdev @ 0x%p pdev->sh_info @ 0x%p\n",
725 pdev, pdev->sh_info);
726out:
727 return pdev;
728}
729
730static void free_pdev(struct pcifront_device *pdev)
731{
732 dev_dbg(&pdev->xdev->dev, "freeing pdev @ 0x%p\n", pdev);
733
734 pcifront_free_roots(pdev);
735
736 /*For PCIE_AER error handling job*/
737 flush_scheduled_work();
738
739 if (pdev->irq >= 0)
740 unbind_from_irqhandler(pdev->irq, pdev);
741
742 if (pdev->evtchn != INVALID_EVTCHN)
743 xenbus_free_evtchn(pdev->xdev, pdev->evtchn);
744
745 if (pdev->gnt_ref != INVALID_GRANT_REF)
746 gnttab_end_foreign_access(pdev->gnt_ref, 0 /* r/w page */,
747 (unsigned long)pdev->sh_info);
748 else
749 free_page((unsigned long)pdev->sh_info);
750
751 dev_set_drvdata(&pdev->xdev->dev, NULL);
752
753 kfree(pdev);
754}
755
756static int pcifront_publish_info(struct pcifront_device *pdev)
757{
758 int err = 0;
759 struct xenbus_transaction trans;
760
761 err = xenbus_grant_ring(pdev->xdev, virt_to_mfn(pdev->sh_info));
762 if (err < 0)
763 goto out;
764
765 pdev->gnt_ref = err;
766
767 err = xenbus_alloc_evtchn(pdev->xdev, &pdev->evtchn);
768 if (err)
769 goto out;
770
771 err = bind_evtchn_to_irqhandler(pdev->evtchn, pcifront_handler_aer,
772 0, "pcifront", pdev);
773
774 if (err < 0)
775 return err;
776
777 pdev->irq = err;
778
779do_publish:
780 err = xenbus_transaction_start(&trans);
781 if (err) {
782 xenbus_dev_fatal(pdev->xdev, err,
783 "Error writing configuration for backend "
784 "(start transaction)");
785 goto out;
786 }
787
788 err = xenbus_printf(trans, pdev->xdev->nodename,
789 "pci-op-ref", "%u", pdev->gnt_ref);
790 if (!err)
791 err = xenbus_printf(trans, pdev->xdev->nodename,
792 "event-channel", "%u", pdev->evtchn);
793 if (!err)
794 err = xenbus_printf(trans, pdev->xdev->nodename,
795 "magic", XEN_PCI_MAGIC);
796
797 if (err) {
798 xenbus_transaction_end(trans, 1);
799 xenbus_dev_fatal(pdev->xdev, err,
800 "Error writing configuration for backend");
801 goto out;
802 } else {
803 err = xenbus_transaction_end(trans, 0);
804 if (err == -EAGAIN)
805 goto do_publish;
806 else if (err) {
807 xenbus_dev_fatal(pdev->xdev, err,
808 "Error completing transaction "
809 "for backend");
810 goto out;
811 }
812 }
813
814 xenbus_switch_state(pdev->xdev, XenbusStateInitialised);
815
816 dev_dbg(&pdev->xdev->dev, "publishing successful!\n");
817
818out:
819 return err;
820}
821
822static int __devinit pcifront_try_connect(struct pcifront_device *pdev)
823{
824 int err = -EFAULT;
825 int i, num_roots, len;
826 char str[64];
827 unsigned int domain, bus;
828
829
830 /* Only connect once */
831 if (xenbus_read_driver_state(pdev->xdev->nodename) !=
832 XenbusStateInitialised)
833 goto out;
834
835 err = pcifront_connect(pdev);
836 if (err) {
837 xenbus_dev_fatal(pdev->xdev, err,
838 "Error connecting PCI Frontend");
839 goto out;
840 }
841
842 err = xenbus_scanf(XBT_NIL, pdev->xdev->otherend,
843 "root_num", "%d", &num_roots);
844 if (err == -ENOENT) {
845 xenbus_dev_error(pdev->xdev, err,
846 "No PCI Roots found, trying 0000:00");
847 err = pcifront_scan_root(pdev, 0, 0);
848 num_roots = 0;
849 } else if (err != 1) {
850 if (err == 0)
851 err = -EINVAL;
852 xenbus_dev_fatal(pdev->xdev, err,
853 "Error reading number of PCI roots");
854 goto out;
855 }
856
857 for (i = 0; i < num_roots; i++) {
858 len = snprintf(str, sizeof(str), "root-%d", i);
859 if (unlikely(len >= (sizeof(str) - 1))) {
860 err = -ENOMEM;
861 goto out;
862 }
863
864 err = xenbus_scanf(XBT_NIL, pdev->xdev->otherend, str,
865 "%x:%x", &domain, &bus);
866 if (err != 2) {
867 if (err >= 0)
868 err = -EINVAL;
869 xenbus_dev_fatal(pdev->xdev, err,
870 "Error reading PCI root %d", i);
871 goto out;
872 }
873
874 err = pcifront_scan_root(pdev, domain, bus);
875 if (err) {
876 xenbus_dev_fatal(pdev->xdev, err,
877 "Error scanning PCI root %04x:%02x",
878 domain, bus);
879 goto out;
880 }
881 }
882
883 err = xenbus_switch_state(pdev->xdev, XenbusStateConnected);
884
885out:
886 return err;
887}
888
889static int pcifront_try_disconnect(struct pcifront_device *pdev)
890{
891 int err = 0;
892 enum xenbus_state prev_state;
893
894
895 prev_state = xenbus_read_driver_state(pdev->xdev->nodename);
896
897 if (prev_state >= XenbusStateClosing)
898 goto out;
899
900 if (prev_state == XenbusStateConnected) {
901 pcifront_free_roots(pdev);
902 pcifront_disconnect(pdev);
903 }
904
905 err = xenbus_switch_state(pdev->xdev, XenbusStateClosed);
906
907out:
908
909 return err;
910}
911
912static int __devinit pcifront_attach_devices(struct pcifront_device *pdev)
913{
914 int err = -EFAULT;
915 int i, num_roots, len;
916 unsigned int domain, bus;
917 char str[64];
918
919 if (xenbus_read_driver_state(pdev->xdev->nodename) !=
920 XenbusStateReconfiguring)
921 goto out;
922
923 err = xenbus_scanf(XBT_NIL, pdev->xdev->otherend,
924 "root_num", "%d", &num_roots);
925 if (err == -ENOENT) {
926 xenbus_dev_error(pdev->xdev, err,
927 "No PCI Roots found, trying 0000:00");
928 err = pcifront_rescan_root(pdev, 0, 0);
929 num_roots = 0;
930 } else if (err != 1) {
931 if (err == 0)
932 err = -EINVAL;
933 xenbus_dev_fatal(pdev->xdev, err,
934 "Error reading number of PCI roots");
935 goto out;
936 }
937
938 for (i = 0; i < num_roots; i++) {
939 len = snprintf(str, sizeof(str), "root-%d", i);
940 if (unlikely(len >= (sizeof(str) - 1))) {
941 err = -ENOMEM;
942 goto out;
943 }
944
945 err = xenbus_scanf(XBT_NIL, pdev->xdev->otherend, str,
946 "%x:%x", &domain, &bus);
947 if (err != 2) {
948 if (err >= 0)
949 err = -EINVAL;
950 xenbus_dev_fatal(pdev->xdev, err,
951 "Error reading PCI root %d", i);
952 goto out;
953 }
954
955 err = pcifront_rescan_root(pdev, domain, bus);
956 if (err) {
957 xenbus_dev_fatal(pdev->xdev, err,
958 "Error scanning PCI root %04x:%02x",
959 domain, bus);
960 goto out;
961 }
962 }
963
964 xenbus_switch_state(pdev->xdev, XenbusStateConnected);
965
966out:
967 return err;
968}
969
970static int pcifront_detach_devices(struct pcifront_device *pdev)
971{
972 int err = 0;
973 int i, num_devs;
974 unsigned int domain, bus, slot, func;
975 struct pci_bus *pci_bus;
976 struct pci_dev *pci_dev;
977 char str[64];
978
979 if (xenbus_read_driver_state(pdev->xdev->nodename) !=
980 XenbusStateConnected)
981 goto out;
982
983 err = xenbus_scanf(XBT_NIL, pdev->xdev->otherend, "num_devs", "%d",
984 &num_devs);
985 if (err != 1) {
986 if (err >= 0)
987 err = -EINVAL;
988 xenbus_dev_fatal(pdev->xdev, err,
989 "Error reading number of PCI devices");
990 goto out;
991 }
992
993 /* Find devices being detached and remove them. */
994 for (i = 0; i < num_devs; i++) {
995 int l, state;
996 l = snprintf(str, sizeof(str), "state-%d", i);
997 if (unlikely(l >= (sizeof(str) - 1))) {
998 err = -ENOMEM;
999 goto out;
1000 }
1001 err = xenbus_scanf(XBT_NIL, pdev->xdev->otherend, str, "%d",
1002 &state);
1003 if (err != 1)
1004 state = XenbusStateUnknown;
1005
1006 if (state != XenbusStateClosing)
1007 continue;
1008
1009 /* Remove device. */
1010 l = snprintf(str, sizeof(str), "vdev-%d", i);
1011 if (unlikely(l >= (sizeof(str) - 1))) {
1012 err = -ENOMEM;
1013 goto out;
1014 }
1015 err = xenbus_scanf(XBT_NIL, pdev->xdev->otherend, str,
1016 "%x:%x:%x.%x", &domain, &bus, &slot, &func);
1017 if (err != 4) {
1018 if (err >= 0)
1019 err = -EINVAL;
1020 xenbus_dev_fatal(pdev->xdev, err,
1021 "Error reading PCI device %d", i);
1022 goto out;
1023 }
1024
1025 pci_bus = pci_find_bus(domain, bus);
1026 if (!pci_bus) {
1027 dev_dbg(&pdev->xdev->dev, "Cannot get bus %04x:%02x\n",
1028 domain, bus);
1029 continue;
1030 }
1031 pci_dev = pci_get_slot(pci_bus, PCI_DEVFN(slot, func));
1032 if (!pci_dev) {
1033 dev_dbg(&pdev->xdev->dev,
1034 "Cannot get PCI device %04x:%02x:%02x.%02x\n",
1035 domain, bus, slot, func);
1036 continue;
1037 }
1038 pci_remove_bus_device(pci_dev);
1039 pci_dev_put(pci_dev);
1040
1041 dev_dbg(&pdev->xdev->dev,
1042 "PCI device %04x:%02x:%02x.%02x removed.\n",
1043 domain, bus, slot, func);
1044 }
1045
1046 err = xenbus_switch_state(pdev->xdev, XenbusStateReconfiguring);
1047
1048out:
1049 return err;
1050}
1051
1052static void __init_refok pcifront_backend_changed(struct xenbus_device *xdev,
1053 enum xenbus_state be_state)
1054{
1055 struct pcifront_device *pdev = dev_get_drvdata(&xdev->dev);
1056
1057 switch (be_state) {
1058 case XenbusStateUnknown:
1059 case XenbusStateInitialising:
1060 case XenbusStateInitWait:
1061 case XenbusStateInitialised:
1062 case XenbusStateClosed:
1063 break;
1064
1065 case XenbusStateConnected:
1066 pcifront_try_connect(pdev);
1067 break;
1068
1069 case XenbusStateClosing:
1070 dev_warn(&xdev->dev, "backend going away!\n");
1071 pcifront_try_disconnect(pdev);
1072 break;
1073
1074 case XenbusStateReconfiguring:
1075 pcifront_detach_devices(pdev);
1076 break;
1077
1078 case XenbusStateReconfigured:
1079 pcifront_attach_devices(pdev);
1080 break;
1081 }
1082}
1083
1084static int pcifront_xenbus_probe(struct xenbus_device *xdev,
1085 const struct xenbus_device_id *id)
1086{
1087 int err = 0;
1088 struct pcifront_device *pdev = alloc_pdev(xdev);
1089
1090 if (pdev == NULL) {
1091 err = -ENOMEM;
1092 xenbus_dev_fatal(xdev, err,
1093 "Error allocating pcifront_device struct");
1094 goto out;
1095 }
1096
1097 err = pcifront_publish_info(pdev);
1098 if (err)
1099 free_pdev(pdev);
1100
1101out:
1102 return err;
1103}
1104
1105static int pcifront_xenbus_remove(struct xenbus_device *xdev)
1106{
1107 struct pcifront_device *pdev = dev_get_drvdata(&xdev->dev);
1108 if (pdev)
1109 free_pdev(pdev);
1110
1111 return 0;
1112}
1113
1114static const struct xenbus_device_id xenpci_ids[] = {
1115 {"pci"},
1116 {""},
1117};
1118
1119static struct xenbus_driver xenbus_pcifront_driver = {
1120 .name = "pcifront",
1121 .owner = THIS_MODULE,
1122 .ids = xenpci_ids,
1123 .probe = pcifront_xenbus_probe,
1124 .remove = pcifront_xenbus_remove,
1125 .otherend_changed = pcifront_backend_changed,
1126};
1127
1128static int __init pcifront_init(void)
1129{
1130 if (!xen_pv_domain() || xen_initial_domain())
1131 return -ENODEV;
1132
1133 pci_frontend_registrar(1 /* enable */);
1134
1135 return xenbus_register_frontend(&xenbus_pcifront_driver);
1136}
1137
1138static void __exit pcifront_cleanup(void)
1139{
1140 xenbus_unregister_driver(&xenbus_pcifront_driver);
1141 pci_frontend_registrar(0 /* disable */);
1142}
1143module_init(pcifront_init);
1144module_exit(pcifront_cleanup);
1145
1146MODULE_DESCRIPTION("Xen PCI passthrough frontend.");
1147MODULE_LICENSE("GPL");
1148MODULE_ALIAS("xen:pci");
Clone of davem's net-next-2.6 tree