blob: 90832a955991f1d875eaf57a01a3b5c90930cb72 [file] [log] [blame]
Ryan Wilson956a9202010-08-02 21:31:05 -04001/*
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>
Ryan Wilson956a9202010-08-02 21:31:05 -040016#include <xen/interface/io/pciif.h>
17#include <asm/xen/pci.h>
18#include <linux/interrupt.h>
Arun Sharma60063492011-07-26 16:09:06 -070019#include <linux/atomic.h>
Ryan Wilson956a9202010-08-02 21:31:05 -040020#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,
Konrad Rzeszutek Wilkcc0f89c2011-02-17 12:02:23 -0500246 int vector[], int nvec)
Ryan Wilson956a9202010-08-02 21:31:05 -0400247{
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 */
Konrad Rzeszutek Wilk1d461052011-02-16 13:43:22 -0500280 for (i = 0; i < nvec; i++) {
281 if (op.msix_entries[i].vector <= 0) {
282 dev_warn(&dev->dev, "MSI-X entry %d is invalid: %d!\n",
283 i, op.msix_entries[i].vector);
284 err = -EINVAL;
Konrad Rzeszutek Wilkcc0f89c2011-02-17 12:02:23 -0500285 vector[i] = -1;
Konrad Rzeszutek Wilk1d461052011-02-16 13:43:22 -0500286 continue;
287 }
Konrad Rzeszutek Wilkcc0f89c2011-02-17 12:02:23 -0500288 vector[i] = op.msix_entries[i].vector;
Konrad Rzeszutek Wilk1d461052011-02-16 13:43:22 -0500289 }
Ryan Wilson956a9202010-08-02 21:31:05 -0400290 } else {
291 printk(KERN_DEBUG "enable msix get value %x\n",
292 op.value);
Ryan Wilson956a9202010-08-02 21:31:05 -0400293 }
294 } else {
295 dev_err(&dev->dev, "enable msix get err %x\n", err);
Ryan Wilson956a9202010-08-02 21:31:05 -0400296 }
Konrad Rzeszutek Wilk1d461052011-02-16 13:43:22 -0500297 return err;
Ryan Wilson956a9202010-08-02 21:31:05 -0400298}
299
300static void pci_frontend_disable_msix(struct pci_dev *dev)
301{
302 int err;
303 struct xen_pci_op op = {
304 .cmd = XEN_PCI_OP_disable_msix,
305 .domain = pci_domain_nr(dev->bus),
306 .bus = dev->bus->number,
307 .devfn = dev->devfn,
308 };
309 struct pcifront_sd *sd = dev->bus->sysdata;
310 struct pcifront_device *pdev = pcifront_get_pdev(sd);
311
312 err = do_pci_op(pdev, &op);
313
314 /* What should do for error ? */
315 if (err)
316 dev_err(&dev->dev, "pci_disable_msix get err %x\n", err);
317}
318
Konrad Rzeszutek Wilkcc0f89c2011-02-17 12:02:23 -0500319static int pci_frontend_enable_msi(struct pci_dev *dev, int vector[])
Ryan Wilson956a9202010-08-02 21:31:05 -0400320{
321 int err;
322 struct xen_pci_op op = {
323 .cmd = XEN_PCI_OP_enable_msi,
324 .domain = pci_domain_nr(dev->bus),
325 .bus = dev->bus->number,
326 .devfn = dev->devfn,
327 };
328 struct pcifront_sd *sd = dev->bus->sysdata;
329 struct pcifront_device *pdev = pcifront_get_pdev(sd);
330
331 err = do_pci_op(pdev, &op);
332 if (likely(!err)) {
Konrad Rzeszutek Wilkcc0f89c2011-02-17 12:02:23 -0500333 vector[0] = op.value;
Konrad Rzeszutek Wilk1d461052011-02-16 13:43:22 -0500334 if (op.value <= 0) {
335 dev_warn(&dev->dev, "MSI entry is invalid: %d!\n",
336 op.value);
337 err = -EINVAL;
Konrad Rzeszutek Wilkcc0f89c2011-02-17 12:02:23 -0500338 vector[0] = -1;
Konrad Rzeszutek Wilk1d461052011-02-16 13:43:22 -0500339 }
Ryan Wilson956a9202010-08-02 21:31:05 -0400340 } else {
341 dev_err(&dev->dev, "pci frontend enable msi failed for dev "
342 "%x:%x\n", op.bus, op.devfn);
343 err = -EINVAL;
344 }
345 return err;
346}
347
348static void pci_frontend_disable_msi(struct pci_dev *dev)
349{
350 int err;
351 struct xen_pci_op op = {
352 .cmd = XEN_PCI_OP_disable_msi,
353 .domain = pci_domain_nr(dev->bus),
354 .bus = dev->bus->number,
355 .devfn = dev->devfn,
356 };
357 struct pcifront_sd *sd = dev->bus->sysdata;
358 struct pcifront_device *pdev = pcifront_get_pdev(sd);
359
360 err = do_pci_op(pdev, &op);
361 if (err == XEN_PCI_ERR_dev_not_found) {
362 /* XXX No response from backend, what shall we do? */
363 printk(KERN_DEBUG "get no response from backend for disable MSI\n");
364 return;
365 }
366 if (err)
367 /* how can pciback notify us fail? */
368 printk(KERN_DEBUG "get fake response frombackend\n");
369}
370
371static struct xen_pci_frontend_ops pci_frontend_ops = {
372 .enable_msi = pci_frontend_enable_msi,
373 .disable_msi = pci_frontend_disable_msi,
374 .enable_msix = pci_frontend_enable_msix,
375 .disable_msix = pci_frontend_disable_msix,
376};
377
378static void pci_frontend_registrar(int enable)
379{
380 if (enable)
381 xen_pci_frontend = &pci_frontend_ops;
382 else
383 xen_pci_frontend = NULL;
384};
385#else
386static inline void pci_frontend_registrar(int enable) { };
387#endif /* CONFIG_PCI_MSI */
388
389/* Claim resources for the PCI frontend as-is, backend won't allow changes */
390static int pcifront_claim_resource(struct pci_dev *dev, void *data)
391{
392 struct pcifront_device *pdev = data;
393 int i;
394 struct resource *r;
395
396 for (i = 0; i < PCI_NUM_RESOURCES; i++) {
397 r = &dev->resource[i];
398
399 if (!r->parent && r->start && r->flags) {
400 dev_info(&pdev->xdev->dev, "claiming resource %s/%d\n",
401 pci_name(dev), i);
402 if (pci_claim_resource(dev, i)) {
Konrad Rzeszutek Wilk917e3e62011-07-22 12:18:43 -0400403 dev_err(&pdev->xdev->dev, "Could not claim resource %s/%d! "
404 "Device offline. Try using e820_host=1 in the guest config.\n",
Ryan Wilson956a9202010-08-02 21:31:05 -0400405 pci_name(dev), i);
406 }
407 }
408 }
409
410 return 0;
411}
412
413static int __devinit pcifront_scan_bus(struct pcifront_device *pdev,
414 unsigned int domain, unsigned int bus,
415 struct pci_bus *b)
416{
417 struct pci_dev *d;
418 unsigned int devfn;
419
420 /* Scan the bus for functions and add.
421 * We omit handling of PCI bridge attachment because pciback prevents
422 * bridges from being exported.
423 */
424 for (devfn = 0; devfn < 0x100; devfn++) {
425 d = pci_get_slot(b, devfn);
426 if (d) {
427 /* Device is already known. */
428 pci_dev_put(d);
429 continue;
430 }
431
432 d = pci_scan_single_device(b, devfn);
433 if (d)
434 dev_info(&pdev->xdev->dev, "New device on "
435 "%04x:%02x:%02x.%02x found.\n", domain, bus,
436 PCI_SLOT(devfn), PCI_FUNC(devfn));
437 }
438
439 return 0;
440}
441
442static int __devinit pcifront_scan_root(struct pcifront_device *pdev,
443 unsigned int domain, unsigned int bus)
444{
445 struct pci_bus *b;
446 struct pcifront_sd *sd = NULL;
447 struct pci_bus_entry *bus_entry = NULL;
448 int err = 0;
449
450#ifndef CONFIG_PCI_DOMAINS
451 if (domain != 0) {
452 dev_err(&pdev->xdev->dev,
453 "PCI Root in non-zero PCI Domain! domain=%d\n", domain);
454 dev_err(&pdev->xdev->dev,
455 "Please compile with CONFIG_PCI_DOMAINS\n");
456 err = -EINVAL;
457 goto err_out;
458 }
459#endif
460
461 dev_info(&pdev->xdev->dev, "Creating PCI Frontend Bus %04x:%02x\n",
462 domain, bus);
463
464 bus_entry = kmalloc(sizeof(*bus_entry), GFP_KERNEL);
465 sd = kmalloc(sizeof(*sd), GFP_KERNEL);
466 if (!bus_entry || !sd) {
467 err = -ENOMEM;
468 goto err_out;
469 }
470 pcifront_init_sd(sd, domain, bus, pdev);
471
472 b = pci_scan_bus_parented(&pdev->xdev->dev, bus,
473 &pcifront_bus_ops, sd);
474 if (!b) {
475 dev_err(&pdev->xdev->dev,
476 "Error creating PCI Frontend Bus!\n");
477 err = -ENOMEM;
478 goto err_out;
479 }
480
481 bus_entry->bus = b;
482
483 list_add(&bus_entry->list, &pdev->root_buses);
484
485 /* pci_scan_bus_parented skips devices which do not have a have
486 * devfn==0. The pcifront_scan_bus enumerates all devfn. */
487 err = pcifront_scan_bus(pdev, domain, bus, b);
488
489 /* Claim resources before going "live" with our devices */
490 pci_walk_bus(b, pcifront_claim_resource, pdev);
491
492 /* Create SysFS and notify udev of the devices. Aka: "going live" */
493 pci_bus_add_devices(b);
494
495 return err;
496
497err_out:
498 kfree(bus_entry);
499 kfree(sd);
500
501 return err;
502}
503
504static int __devinit pcifront_rescan_root(struct pcifront_device *pdev,
505 unsigned int domain, unsigned int bus)
506{
507 int err;
508 struct pci_bus *b;
509
510#ifndef CONFIG_PCI_DOMAINS
511 if (domain != 0) {
512 dev_err(&pdev->xdev->dev,
513 "PCI Root in non-zero PCI Domain! domain=%d\n", domain);
514 dev_err(&pdev->xdev->dev,
515 "Please compile with CONFIG_PCI_DOMAINS\n");
516 return -EINVAL;
517 }
518#endif
519
520 dev_info(&pdev->xdev->dev, "Rescanning PCI Frontend Bus %04x:%02x\n",
521 domain, bus);
522
523 b = pci_find_bus(domain, bus);
524 if (!b)
525 /* If the bus is unknown, create it. */
526 return pcifront_scan_root(pdev, domain, bus);
527
528 err = pcifront_scan_bus(pdev, domain, bus, b);
529
530 /* Claim resources before going "live" with our devices */
531 pci_walk_bus(b, pcifront_claim_resource, pdev);
532
533 /* Create SysFS and notify udev of the devices. Aka: "going live" */
534 pci_bus_add_devices(b);
535
536 return err;
537}
538
539static void free_root_bus_devs(struct pci_bus *bus)
540{
541 struct pci_dev *dev;
542
543 while (!list_empty(&bus->devices)) {
544 dev = container_of(bus->devices.next, struct pci_dev,
545 bus_list);
546 dev_dbg(&dev->dev, "removing device\n");
547 pci_remove_bus_device(dev);
548 }
549}
550
551static void pcifront_free_roots(struct pcifront_device *pdev)
552{
553 struct pci_bus_entry *bus_entry, *t;
554
555 dev_dbg(&pdev->xdev->dev, "cleaning up root buses\n");
556
557 list_for_each_entry_safe(bus_entry, t, &pdev->root_buses, list) {
558 list_del(&bus_entry->list);
559
560 free_root_bus_devs(bus_entry->bus);
561
562 kfree(bus_entry->bus->sysdata);
563
564 device_unregister(bus_entry->bus->bridge);
565 pci_remove_bus(bus_entry->bus);
566
567 kfree(bus_entry);
568 }
569}
570
571static pci_ers_result_t pcifront_common_process(int cmd,
572 struct pcifront_device *pdev,
573 pci_channel_state_t state)
574{
575 pci_ers_result_t result;
576 struct pci_driver *pdrv;
577 int bus = pdev->sh_info->aer_op.bus;
578 int devfn = pdev->sh_info->aer_op.devfn;
579 struct pci_dev *pcidev;
580 int flag = 0;
581
582 dev_dbg(&pdev->xdev->dev,
583 "pcifront AER process: cmd %x (bus:%x, devfn%x)",
584 cmd, bus, devfn);
585 result = PCI_ERS_RESULT_NONE;
586
587 pcidev = pci_get_bus_and_slot(bus, devfn);
588 if (!pcidev || !pcidev->driver) {
Jiri Slaby2a63dd72010-11-04 15:31:30 +0100589 dev_err(&pdev->xdev->dev, "device or AER driver is NULL\n");
590 if (pcidev)
591 pci_dev_put(pcidev);
Ryan Wilson956a9202010-08-02 21:31:05 -0400592 return result;
593 }
594 pdrv = pcidev->driver;
595
596 if (get_driver(&pdrv->driver)) {
597 if (pdrv->err_handler && pdrv->err_handler->error_detected) {
598 dev_dbg(&pcidev->dev,
599 "trying to call AER service\n");
600 if (pcidev) {
601 flag = 1;
602 switch (cmd) {
603 case XEN_PCI_OP_aer_detected:
604 result = pdrv->err_handler->
605 error_detected(pcidev, state);
606 break;
607 case XEN_PCI_OP_aer_mmio:
608 result = pdrv->err_handler->
609 mmio_enabled(pcidev);
610 break;
611 case XEN_PCI_OP_aer_slotreset:
612 result = pdrv->err_handler->
613 slot_reset(pcidev);
614 break;
615 case XEN_PCI_OP_aer_resume:
616 pdrv->err_handler->resume(pcidev);
617 break;
618 default:
619 dev_err(&pdev->xdev->dev,
620 "bad request in aer recovery "
621 "operation!\n");
622
623 }
624 }
625 }
626 put_driver(&pdrv->driver);
627 }
628 if (!flag)
629 result = PCI_ERS_RESULT_NONE;
630
631 return result;
632}
633
634
635static void pcifront_do_aer(struct work_struct *data)
636{
637 struct pcifront_device *pdev =
638 container_of(data, struct pcifront_device, op_work);
639 int cmd = pdev->sh_info->aer_op.cmd;
640 pci_channel_state_t state =
641 (pci_channel_state_t)pdev->sh_info->aer_op.err;
642
643 /*If a pci_conf op is in progress,
644 we have to wait until it is done before service aer op*/
645 dev_dbg(&pdev->xdev->dev,
646 "pcifront service aer bus %x devfn %x\n",
647 pdev->sh_info->aer_op.bus, pdev->sh_info->aer_op.devfn);
648
649 pdev->sh_info->aer_op.err = pcifront_common_process(cmd, pdev, state);
650
651 /* Post the operation to the guest. */
652 wmb();
653 clear_bit(_XEN_PCIB_active, (unsigned long *)&pdev->sh_info->flags);
654 notify_remote_via_evtchn(pdev->evtchn);
655
656 /*in case of we lost an aer request in four lines time_window*/
657 smp_mb__before_clear_bit();
658 clear_bit(_PDEVB_op_active, &pdev->flags);
659 smp_mb__after_clear_bit();
660
661 schedule_pcifront_aer_op(pdev);
662
663}
664
665static irqreturn_t pcifront_handler_aer(int irq, void *dev)
666{
667 struct pcifront_device *pdev = dev;
668 schedule_pcifront_aer_op(pdev);
669 return IRQ_HANDLED;
670}
671static int pcifront_connect(struct pcifront_device *pdev)
672{
673 int err = 0;
674
675 spin_lock(&pcifront_dev_lock);
676
677 if (!pcifront_dev) {
678 dev_info(&pdev->xdev->dev, "Installing PCI frontend\n");
679 pcifront_dev = pdev;
680 } else {
681 dev_err(&pdev->xdev->dev, "PCI frontend already installed!\n");
682 err = -EEXIST;
683 }
684
685 spin_unlock(&pcifront_dev_lock);
686
687 return err;
688}
689
690static void pcifront_disconnect(struct pcifront_device *pdev)
691{
692 spin_lock(&pcifront_dev_lock);
693
694 if (pdev == pcifront_dev) {
695 dev_info(&pdev->xdev->dev,
696 "Disconnecting PCI Frontend Buses\n");
697 pcifront_dev = NULL;
698 }
699
700 spin_unlock(&pcifront_dev_lock);
701}
702static struct pcifront_device *alloc_pdev(struct xenbus_device *xdev)
703{
704 struct pcifront_device *pdev;
705
706 pdev = kzalloc(sizeof(struct pcifront_device), GFP_KERNEL);
707 if (pdev == NULL)
708 goto out;
709
710 pdev->sh_info =
711 (struct xen_pci_sharedinfo *)__get_free_page(GFP_KERNEL);
712 if (pdev->sh_info == NULL) {
713 kfree(pdev);
714 pdev = NULL;
715 goto out;
716 }
717 pdev->sh_info->flags = 0;
718
719 /*Flag for registering PV AER handler*/
720 set_bit(_XEN_PCIB_AERHANDLER, (void *)&pdev->sh_info->flags);
721
722 dev_set_drvdata(&xdev->dev, pdev);
723 pdev->xdev = xdev;
724
725 INIT_LIST_HEAD(&pdev->root_buses);
726
727 spin_lock_init(&pdev->sh_info_lock);
728
729 pdev->evtchn = INVALID_EVTCHN;
730 pdev->gnt_ref = INVALID_GRANT_REF;
731 pdev->irq = -1;
732
733 INIT_WORK(&pdev->op_work, pcifront_do_aer);
734
735 dev_dbg(&xdev->dev, "Allocated pdev @ 0x%p pdev->sh_info @ 0x%p\n",
736 pdev, pdev->sh_info);
737out:
738 return pdev;
739}
740
741static void free_pdev(struct pcifront_device *pdev)
742{
743 dev_dbg(&pdev->xdev->dev, "freeing pdev @ 0x%p\n", pdev);
744
745 pcifront_free_roots(pdev);
746
Tejun Heodb2e2e62011-01-24 15:43:03 +0100747 cancel_work_sync(&pdev->op_work);
Ryan Wilson956a9202010-08-02 21:31:05 -0400748
749 if (pdev->irq >= 0)
750 unbind_from_irqhandler(pdev->irq, pdev);
751
752 if (pdev->evtchn != INVALID_EVTCHN)
753 xenbus_free_evtchn(pdev->xdev, pdev->evtchn);
754
755 if (pdev->gnt_ref != INVALID_GRANT_REF)
756 gnttab_end_foreign_access(pdev->gnt_ref, 0 /* r/w page */,
757 (unsigned long)pdev->sh_info);
758 else
759 free_page((unsigned long)pdev->sh_info);
760
761 dev_set_drvdata(&pdev->xdev->dev, NULL);
762
763 kfree(pdev);
764}
765
766static int pcifront_publish_info(struct pcifront_device *pdev)
767{
768 int err = 0;
769 struct xenbus_transaction trans;
770
771 err = xenbus_grant_ring(pdev->xdev, virt_to_mfn(pdev->sh_info));
772 if (err < 0)
773 goto out;
774
775 pdev->gnt_ref = err;
776
777 err = xenbus_alloc_evtchn(pdev->xdev, &pdev->evtchn);
778 if (err)
779 goto out;
780
781 err = bind_evtchn_to_irqhandler(pdev->evtchn, pcifront_handler_aer,
782 0, "pcifront", pdev);
783
784 if (err < 0)
785 return err;
786
787 pdev->irq = err;
788
789do_publish:
790 err = xenbus_transaction_start(&trans);
791 if (err) {
792 xenbus_dev_fatal(pdev->xdev, err,
793 "Error writing configuration for backend "
794 "(start transaction)");
795 goto out;
796 }
797
798 err = xenbus_printf(trans, pdev->xdev->nodename,
799 "pci-op-ref", "%u", pdev->gnt_ref);
800 if (!err)
801 err = xenbus_printf(trans, pdev->xdev->nodename,
802 "event-channel", "%u", pdev->evtchn);
803 if (!err)
804 err = xenbus_printf(trans, pdev->xdev->nodename,
805 "magic", XEN_PCI_MAGIC);
806
807 if (err) {
808 xenbus_transaction_end(trans, 1);
809 xenbus_dev_fatal(pdev->xdev, err,
810 "Error writing configuration for backend");
811 goto out;
812 } else {
813 err = xenbus_transaction_end(trans, 0);
814 if (err == -EAGAIN)
815 goto do_publish;
816 else if (err) {
817 xenbus_dev_fatal(pdev->xdev, err,
818 "Error completing transaction "
819 "for backend");
820 goto out;
821 }
822 }
823
824 xenbus_switch_state(pdev->xdev, XenbusStateInitialised);
825
826 dev_dbg(&pdev->xdev->dev, "publishing successful!\n");
827
828out:
829 return err;
830}
831
832static int __devinit pcifront_try_connect(struct pcifront_device *pdev)
833{
834 int err = -EFAULT;
835 int i, num_roots, len;
836 char str[64];
837 unsigned int domain, bus;
838
839
840 /* Only connect once */
841 if (xenbus_read_driver_state(pdev->xdev->nodename) !=
842 XenbusStateInitialised)
843 goto out;
844
845 err = pcifront_connect(pdev);
846 if (err) {
847 xenbus_dev_fatal(pdev->xdev, err,
848 "Error connecting PCI Frontend");
849 goto out;
850 }
851
852 err = xenbus_scanf(XBT_NIL, pdev->xdev->otherend,
853 "root_num", "%d", &num_roots);
854 if (err == -ENOENT) {
855 xenbus_dev_error(pdev->xdev, err,
856 "No PCI Roots found, trying 0000:00");
857 err = pcifront_scan_root(pdev, 0, 0);
858 num_roots = 0;
859 } else if (err != 1) {
860 if (err == 0)
861 err = -EINVAL;
862 xenbus_dev_fatal(pdev->xdev, err,
863 "Error reading number of PCI roots");
864 goto out;
865 }
866
867 for (i = 0; i < num_roots; i++) {
868 len = snprintf(str, sizeof(str), "root-%d", i);
869 if (unlikely(len >= (sizeof(str) - 1))) {
870 err = -ENOMEM;
871 goto out;
872 }
873
874 err = xenbus_scanf(XBT_NIL, pdev->xdev->otherend, str,
875 "%x:%x", &domain, &bus);
876 if (err != 2) {
877 if (err >= 0)
878 err = -EINVAL;
879 xenbus_dev_fatal(pdev->xdev, err,
880 "Error reading PCI root %d", i);
881 goto out;
882 }
883
884 err = pcifront_scan_root(pdev, domain, bus);
885 if (err) {
886 xenbus_dev_fatal(pdev->xdev, err,
887 "Error scanning PCI root %04x:%02x",
888 domain, bus);
889 goto out;
890 }
891 }
892
893 err = xenbus_switch_state(pdev->xdev, XenbusStateConnected);
894
895out:
896 return err;
897}
898
899static int pcifront_try_disconnect(struct pcifront_device *pdev)
900{
901 int err = 0;
902 enum xenbus_state prev_state;
903
904
905 prev_state = xenbus_read_driver_state(pdev->xdev->nodename);
906
907 if (prev_state >= XenbusStateClosing)
908 goto out;
909
910 if (prev_state == XenbusStateConnected) {
911 pcifront_free_roots(pdev);
912 pcifront_disconnect(pdev);
913 }
914
915 err = xenbus_switch_state(pdev->xdev, XenbusStateClosed);
916
917out:
918
919 return err;
920}
921
922static int __devinit pcifront_attach_devices(struct pcifront_device *pdev)
923{
924 int err = -EFAULT;
925 int i, num_roots, len;
926 unsigned int domain, bus;
927 char str[64];
928
929 if (xenbus_read_driver_state(pdev->xdev->nodename) !=
930 XenbusStateReconfiguring)
931 goto out;
932
933 err = xenbus_scanf(XBT_NIL, pdev->xdev->otherend,
934 "root_num", "%d", &num_roots);
935 if (err == -ENOENT) {
936 xenbus_dev_error(pdev->xdev, err,
937 "No PCI Roots found, trying 0000:00");
938 err = pcifront_rescan_root(pdev, 0, 0);
939 num_roots = 0;
940 } else if (err != 1) {
941 if (err == 0)
942 err = -EINVAL;
943 xenbus_dev_fatal(pdev->xdev, err,
944 "Error reading number of PCI roots");
945 goto out;
946 }
947
948 for (i = 0; i < num_roots; i++) {
949 len = snprintf(str, sizeof(str), "root-%d", i);
950 if (unlikely(len >= (sizeof(str) - 1))) {
951 err = -ENOMEM;
952 goto out;
953 }
954
955 err = xenbus_scanf(XBT_NIL, pdev->xdev->otherend, str,
956 "%x:%x", &domain, &bus);
957 if (err != 2) {
958 if (err >= 0)
959 err = -EINVAL;
960 xenbus_dev_fatal(pdev->xdev, err,
961 "Error reading PCI root %d", i);
962 goto out;
963 }
964
965 err = pcifront_rescan_root(pdev, domain, bus);
966 if (err) {
967 xenbus_dev_fatal(pdev->xdev, err,
968 "Error scanning PCI root %04x:%02x",
969 domain, bus);
970 goto out;
971 }
972 }
973
974 xenbus_switch_state(pdev->xdev, XenbusStateConnected);
975
976out:
977 return err;
978}
979
980static int pcifront_detach_devices(struct pcifront_device *pdev)
981{
982 int err = 0;
983 int i, num_devs;
984 unsigned int domain, bus, slot, func;
985 struct pci_bus *pci_bus;
986 struct pci_dev *pci_dev;
987 char str[64];
988
989 if (xenbus_read_driver_state(pdev->xdev->nodename) !=
990 XenbusStateConnected)
991 goto out;
992
993 err = xenbus_scanf(XBT_NIL, pdev->xdev->otherend, "num_devs", "%d",
994 &num_devs);
995 if (err != 1) {
996 if (err >= 0)
997 err = -EINVAL;
998 xenbus_dev_fatal(pdev->xdev, err,
999 "Error reading number of PCI devices");
1000 goto out;
1001 }
1002
1003 /* Find devices being detached and remove them. */
1004 for (i = 0; i < num_devs; i++) {
1005 int l, state;
1006 l = snprintf(str, sizeof(str), "state-%d", i);
1007 if (unlikely(l >= (sizeof(str) - 1))) {
1008 err = -ENOMEM;
1009 goto out;
1010 }
1011 err = xenbus_scanf(XBT_NIL, pdev->xdev->otherend, str, "%d",
1012 &state);
1013 if (err != 1)
1014 state = XenbusStateUnknown;
1015
1016 if (state != XenbusStateClosing)
1017 continue;
1018
1019 /* Remove device. */
1020 l = snprintf(str, sizeof(str), "vdev-%d", i);
1021 if (unlikely(l >= (sizeof(str) - 1))) {
1022 err = -ENOMEM;
1023 goto out;
1024 }
1025 err = xenbus_scanf(XBT_NIL, pdev->xdev->otherend, str,
1026 "%x:%x:%x.%x", &domain, &bus, &slot, &func);
1027 if (err != 4) {
1028 if (err >= 0)
1029 err = -EINVAL;
1030 xenbus_dev_fatal(pdev->xdev, err,
1031 "Error reading PCI device %d", i);
1032 goto out;
1033 }
1034
1035 pci_bus = pci_find_bus(domain, bus);
1036 if (!pci_bus) {
1037 dev_dbg(&pdev->xdev->dev, "Cannot get bus %04x:%02x\n",
1038 domain, bus);
1039 continue;
1040 }
1041 pci_dev = pci_get_slot(pci_bus, PCI_DEVFN(slot, func));
1042 if (!pci_dev) {
1043 dev_dbg(&pdev->xdev->dev,
1044 "Cannot get PCI device %04x:%02x:%02x.%02x\n",
1045 domain, bus, slot, func);
1046 continue;
1047 }
1048 pci_remove_bus_device(pci_dev);
1049 pci_dev_put(pci_dev);
1050
1051 dev_dbg(&pdev->xdev->dev,
1052 "PCI device %04x:%02x:%02x.%02x removed.\n",
1053 domain, bus, slot, func);
1054 }
1055
1056 err = xenbus_switch_state(pdev->xdev, XenbusStateReconfiguring);
1057
1058out:
1059 return err;
1060}
1061
1062static void __init_refok pcifront_backend_changed(struct xenbus_device *xdev,
1063 enum xenbus_state be_state)
1064{
1065 struct pcifront_device *pdev = dev_get_drvdata(&xdev->dev);
1066
1067 switch (be_state) {
1068 case XenbusStateUnknown:
1069 case XenbusStateInitialising:
1070 case XenbusStateInitWait:
1071 case XenbusStateInitialised:
1072 case XenbusStateClosed:
1073 break;
1074
1075 case XenbusStateConnected:
1076 pcifront_try_connect(pdev);
1077 break;
1078
1079 case XenbusStateClosing:
1080 dev_warn(&xdev->dev, "backend going away!\n");
1081 pcifront_try_disconnect(pdev);
1082 break;
1083
1084 case XenbusStateReconfiguring:
1085 pcifront_detach_devices(pdev);
1086 break;
1087
1088 case XenbusStateReconfigured:
1089 pcifront_attach_devices(pdev);
1090 break;
1091 }
1092}
1093
1094static int pcifront_xenbus_probe(struct xenbus_device *xdev,
1095 const struct xenbus_device_id *id)
1096{
1097 int err = 0;
1098 struct pcifront_device *pdev = alloc_pdev(xdev);
1099
1100 if (pdev == NULL) {
1101 err = -ENOMEM;
1102 xenbus_dev_fatal(xdev, err,
1103 "Error allocating pcifront_device struct");
1104 goto out;
1105 }
1106
1107 err = pcifront_publish_info(pdev);
1108 if (err)
1109 free_pdev(pdev);
1110
1111out:
1112 return err;
1113}
1114
1115static int pcifront_xenbus_remove(struct xenbus_device *xdev)
1116{
1117 struct pcifront_device *pdev = dev_get_drvdata(&xdev->dev);
1118 if (pdev)
1119 free_pdev(pdev);
1120
1121 return 0;
1122}
1123
1124static const struct xenbus_device_id xenpci_ids[] = {
1125 {"pci"},
1126 {""},
1127};
1128
1129static struct xenbus_driver xenbus_pcifront_driver = {
1130 .name = "pcifront",
1131 .owner = THIS_MODULE,
1132 .ids = xenpci_ids,
1133 .probe = pcifront_xenbus_probe,
1134 .remove = pcifront_xenbus_remove,
1135 .otherend_changed = pcifront_backend_changed,
1136};
1137
1138static int __init pcifront_init(void)
1139{
1140 if (!xen_pv_domain() || xen_initial_domain())
1141 return -ENODEV;
1142
1143 pci_frontend_registrar(1 /* enable */);
1144
1145 return xenbus_register_frontend(&xenbus_pcifront_driver);
1146}
1147
1148static void __exit pcifront_cleanup(void)
1149{
1150 xenbus_unregister_driver(&xenbus_pcifront_driver);
1151 pci_frontend_registrar(0 /* disable */);
1152}
1153module_init(pcifront_init);
1154module_exit(pcifront_cleanup);
1155
1156MODULE_DESCRIPTION("Xen PCI passthrough frontend.");
1157MODULE_LICENSE("GPL");
1158MODULE_ALIAS("xen:pci");