projects / GitHub / mt8127 / android_kernel_alcatel_ttab.git / blob
? search:


f7197a790341a0c1de8b4a7dfa2c22377cfdf5c5
[GitHub/mt8127/android_kernel_alcatel_ttab.git] / drivers / pci / xen-pcifront.c
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>
16 #include <xen/interface/io/pciif.h>
17 #include <asm/xen/pci.h>
18 #include <linux/interrupt.h>
19 #include <linux/atomic.h>
20 #include <linux/workqueue.h>
21 #include <linux/bitops.h>
22 #include <linux/time.h>
23
24 #include <asm/xen/swiotlb-xen.h>
25 #define INVALID_GRANT_REF (0)
26 #define INVALID_EVTCHN (-1)
27
28 struct pci_bus_entry {
29 struct list_head list;
30 struct pci_bus *bus;
31 };
32
33 #define _PDEVB_op_active (0)
34 #define PDEVB_op_active (1 << (_PDEVB_op_active))
35
36 struct pcifront_device {
37 struct xenbus_device *xdev;
38 struct list_head root_buses;
39
40 int evtchn;
41 int gnt_ref;
42
43 int irq;
44
45 /* Lock this when doing any operations in sh_info */
46 spinlock_t sh_info_lock;
47 struct xen_pci_sharedinfo *sh_info;
48 struct work_struct op_work;
49 unsigned long flags;
50
51 };
52
53 struct pcifront_sd {
54 int domain;
55 struct pcifront_device *pdev;
56 };
57
58 static inline struct pcifront_device *
59 pcifront_get_pdev(struct pcifront_sd *sd)
60 {
61 return sd->pdev;
62 }
63
64 static inline void pcifront_init_sd(struct pcifront_sd *sd,
65 unsigned int domain, unsigned int bus,
66 struct pcifront_device *pdev)
67 {
68 sd->domain = domain;
69 sd->pdev = pdev;
70 }
71
72 static DEFINE_SPINLOCK(pcifront_dev_lock);
73 static struct pcifront_device *pcifront_dev;
74
75 static int verbose_request;
76 module_param(verbose_request, int, 0644);
77
78 static int errno_to_pcibios_err(int errno)
79 {
80 switch (errno) {
81 case XEN_PCI_ERR_success:
82 return PCIBIOS_SUCCESSFUL;
83
84 case XEN_PCI_ERR_dev_not_found:
85 return PCIBIOS_DEVICE_NOT_FOUND;
86
87 case XEN_PCI_ERR_invalid_offset:
88 case XEN_PCI_ERR_op_failed:
89 return PCIBIOS_BAD_REGISTER_NUMBER;
90
91 case XEN_PCI_ERR_not_implemented:
92 return PCIBIOS_FUNC_NOT_SUPPORTED;
93
94 case XEN_PCI_ERR_access_denied:
95 return PCIBIOS_SET_FAILED;
96 }
97 return errno;
98 }
99
100 static inline void schedule_pcifront_aer_op(struct pcifront_device *pdev)
101 {
102 if (test_bit(_XEN_PCIB_active, (unsigned long *)&pdev->sh_info->flags)
103 && !test_and_set_bit(_PDEVB_op_active, &pdev->flags)) {
104 dev_dbg(&pdev->xdev->dev, "schedule aer frontend job\n");
105 schedule_work(&pdev->op_work);
106 }
107 }
108
109 static int do_pci_op(struct pcifront_device *pdev, struct xen_pci_op *op)
110 {
111 int err = 0;
112 struct xen_pci_op *active_op = &pdev->sh_info->op;
113 unsigned long irq_flags;
114 evtchn_port_t port = pdev->evtchn;
115 unsigned irq = pdev->irq;
116 s64 ns, ns_timeout;
117 struct timeval tv;
118
119 spin_lock_irqsave(&pdev->sh_info_lock, irq_flags);
120
121 memcpy(active_op, op, sizeof(struct xen_pci_op));
122
123 /* Go */
124 wmb();
125 set_bit(_XEN_PCIF_active, (unsigned long *)&pdev->sh_info->flags);
126 notify_remote_via_evtchn(port);
127
128 /*
129 * We set a poll timeout of 3 seconds but give up on return after
130 * 2 seconds. It is better to time out too late rather than too early
131 * (in the latter case we end up continually re-executing poll() with a
132 * timeout in the past). 1s difference gives plenty of slack for error.
133 */
134 do_gettimeofday(&tv);
135 ns_timeout = timeval_to_ns(&tv) + 2 * (s64)NSEC_PER_SEC;
136
137 xen_clear_irq_pending(irq);
138
139 while (test_bit(_XEN_PCIF_active,
140 (unsigned long *)&pdev->sh_info->flags)) {
141 xen_poll_irq_timeout(irq, jiffies + 3*HZ);
142 xen_clear_irq_pending(irq);
143 do_gettimeofday(&tv);
144 ns = timeval_to_ns(&tv);
145 if (ns > ns_timeout) {
146 dev_err(&pdev->xdev->dev,
147 "pciback not responding!!!\n");
148 clear_bit(_XEN_PCIF_active,
149 (unsigned long *)&pdev->sh_info->flags);
150 err = XEN_PCI_ERR_dev_not_found;
151 goto out;
152 }
153 }
154
155 /*
156 * We might lose backend service request since we
157 * reuse same evtchn with pci_conf backend response. So re-schedule
158 * aer pcifront service.
159 */
160 if (test_bit(_XEN_PCIB_active,
161 (unsigned long *)&pdev->sh_info->flags)) {
162 dev_err(&pdev->xdev->dev,
163 "schedule aer pcifront service\n");
164 schedule_pcifront_aer_op(pdev);
165 }
166
167 memcpy(op, active_op, sizeof(struct xen_pci_op));
168
169 err = op->err;
170 out:
171 spin_unlock_irqrestore(&pdev->sh_info_lock, irq_flags);
172 return err;
173 }
174
175 /* Access to this function is spinlocked in drivers/pci/access.c */
176 static int pcifront_bus_read(struct pci_bus *bus, unsigned int devfn,
177 int where, int size, u32 *val)
178 {
179 int err = 0;
180 struct xen_pci_op op = {
181 .cmd = XEN_PCI_OP_conf_read,
182 .domain = pci_domain_nr(bus),
183 .bus = bus->number,
184 .devfn = devfn,
185 .offset = where,
186 .size = size,
187 };
188 struct pcifront_sd *sd = bus->sysdata;
189 struct pcifront_device *pdev = pcifront_get_pdev(sd);
190
191 if (verbose_request)
192 dev_info(&pdev->xdev->dev,
193 "read dev=%04x:%02x:%02x.%d - offset %x size %d\n",
194 pci_domain_nr(bus), bus->number, PCI_SLOT(devfn),
195 PCI_FUNC(devfn), where, size);
196
197 err = do_pci_op(pdev, &op);
198
199 if (likely(!err)) {
200 if (verbose_request)
201 dev_info(&pdev->xdev->dev, "read got back value %x\n",
202 op.value);
203
204 *val = op.value;
205 } else if (err == -ENODEV) {
206 /* No device here, pretend that it just returned 0 */
207 err = 0;
208 *val = 0;
209 }
210
211 return errno_to_pcibios_err(err);
212 }
213
214 /* Access to this function is spinlocked in drivers/pci/access.c */
215 static int pcifront_bus_write(struct pci_bus *bus, unsigned int devfn,
216 int where, int size, u32 val)
217 {
218 struct xen_pci_op op = {
219 .cmd = XEN_PCI_OP_conf_write,
220 .domain = pci_domain_nr(bus),
221 .bus = bus->number,
222 .devfn = devfn,
223 .offset = where,
224 .size = size,
225 .value = val,
226 };
227 struct pcifront_sd *sd = bus->sysdata;
228 struct pcifront_device *pdev = pcifront_get_pdev(sd);
229
230 if (verbose_request)
231 dev_info(&pdev->xdev->dev,
232 "write dev=%04x:%02x:%02x.%d - "
233 "offset %x size %d val %x\n",
234 pci_domain_nr(bus), bus->number,
235 PCI_SLOT(devfn), PCI_FUNC(devfn), where, size, val);
236
237 return errno_to_pcibios_err(do_pci_op(pdev, &op));
238 }
239
240 static struct pci_ops pcifront_bus_ops = {
241 .read = pcifront_bus_read,
242 .write = pcifront_bus_write,
243 };
244
245 #ifdef CONFIG_PCI_MSI
246 static int pci_frontend_enable_msix(struct pci_dev *dev,
247 int vector[], int nvec)
248 {
249 int err;
250 int i;
251 struct xen_pci_op op = {
252 .cmd = XEN_PCI_OP_enable_msix,
253 .domain = pci_domain_nr(dev->bus),
254 .bus = dev->bus->number,
255 .devfn = dev->devfn,
256 .value = nvec,
257 };
258 struct pcifront_sd *sd = dev->bus->sysdata;
259 struct pcifront_device *pdev = pcifront_get_pdev(sd);
260 struct msi_desc *entry;
261
262 if (nvec > SH_INFO_MAX_VEC) {
263 dev_err(&dev->dev, "too much vector for pci frontend: %x."
264 " Increase SH_INFO_MAX_VEC.\n", nvec);
265 return -EINVAL;
266 }
267
268 i = 0;
269 list_for_each_entry(entry, &dev->msi_list, list) {
270 op.msix_entries[i].entry = entry->msi_attrib.entry_nr;
271 /* Vector is useless at this point. */
272 op.msix_entries[i].vector = -1;
273 i++;
274 }
275
276 err = do_pci_op(pdev, &op);
277
278 if (likely(!err)) {
279 if (likely(!op.value)) {
280 /* we get the result */
281 for (i = 0; i < nvec; i++) {
282 if (op.msix_entries[i].vector <= 0) {
283 dev_warn(&dev->dev, "MSI-X entry %d is invalid: %d!\n",
284 i, op.msix_entries[i].vector);
285 err = -EINVAL;
286 vector[i] = -1;
287 continue;
288 }
289 vector[i] = op.msix_entries[i].vector;
290 }
291 } else {
292 printk(KERN_DEBUG "enable msix get value %x\n",
293 op.value);
294 err = op.value;
295 }
296 } else {
297 dev_err(&dev->dev, "enable msix get err %x\n", err);
298 }
299 return err;
300 }
301
302 static void pci_frontend_disable_msix(struct pci_dev *dev)
303 {
304 int err;
305 struct xen_pci_op op = {
306 .cmd = XEN_PCI_OP_disable_msix,
307 .domain = pci_domain_nr(dev->bus),
308 .bus = dev->bus->number,
309 .devfn = dev->devfn,
310 };
311 struct pcifront_sd *sd = dev->bus->sysdata;
312 struct pcifront_device *pdev = pcifront_get_pdev(sd);
313
314 err = do_pci_op(pdev, &op);
315
316 /* What should do for error ? */
317 if (err)
318 dev_err(&dev->dev, "pci_disable_msix get err %x\n", err);
319 }
320
321 static int pci_frontend_enable_msi(struct pci_dev *dev, int vector[])
322 {
323 int err;
324 struct xen_pci_op op = {
325 .cmd = XEN_PCI_OP_enable_msi,
326 .domain = pci_domain_nr(dev->bus),
327 .bus = dev->bus->number,
328 .devfn = dev->devfn,
329 };
330 struct pcifront_sd *sd = dev->bus->sysdata;
331 struct pcifront_device *pdev = pcifront_get_pdev(sd);
332
333 err = do_pci_op(pdev, &op);
334 if (likely(!err)) {
335 vector[0] = op.value;
336 if (op.value <= 0) {
337 dev_warn(&dev->dev, "MSI entry is invalid: %d!\n",
338 op.value);
339 err = -EINVAL;
340 vector[0] = -1;
341 }
342 } else {
343 dev_err(&dev->dev, "pci frontend enable msi failed for dev "
344 "%x:%x\n", op.bus, op.devfn);
345 err = -EINVAL;
346 }
347 return err;
348 }
349
350 static void pci_frontend_disable_msi(struct pci_dev *dev)
351 {
352 int err;
353 struct xen_pci_op op = {
354 .cmd = XEN_PCI_OP_disable_msi,
355 .domain = pci_domain_nr(dev->bus),
356 .bus = dev->bus->number,
357 .devfn = dev->devfn,
358 };
359 struct pcifront_sd *sd = dev->bus->sysdata;
360 struct pcifront_device *pdev = pcifront_get_pdev(sd);
361
362 err = do_pci_op(pdev, &op);
363 if (err == XEN_PCI_ERR_dev_not_found) {
364 /* XXX No response from backend, what shall we do? */
365 printk(KERN_DEBUG "get no response from backend for disable MSI\n");
366 return;
367 }
368 if (err)
369 /* how can pciback notify us fail? */
370 printk(KERN_DEBUG "get fake response frombackend\n");
371 }
372
373 static struct xen_pci_frontend_ops pci_frontend_ops = {
374 .enable_msi = pci_frontend_enable_msi,
375 .disable_msi = pci_frontend_disable_msi,
376 .enable_msix = pci_frontend_enable_msix,
377 .disable_msix = pci_frontend_disable_msix,
378 };
379
380 static void pci_frontend_registrar(int enable)
381 {
382 if (enable)
383 xen_pci_frontend = &pci_frontend_ops;
384 else
385 xen_pci_frontend = NULL;
386 };
387 #else
388 static inline void pci_frontend_registrar(int enable) { };
389 #endif /* CONFIG_PCI_MSI */
390
391 /* Claim resources for the PCI frontend as-is, backend won't allow changes */
392 static int pcifront_claim_resource(struct pci_dev *dev, void *data)
393 {
394 struct pcifront_device *pdev = data;
395 int i;
396 struct resource *r;
397
398 for (i = 0; i < PCI_NUM_RESOURCES; i++) {
399 r = &dev->resource[i];
400
401 if (!r->parent && r->start && r->flags) {
402 dev_info(&pdev->xdev->dev, "claiming resource %s/%d\n",
403 pci_name(dev), i);
404 if (pci_claim_resource(dev, i)) {
405 dev_err(&pdev->xdev->dev, "Could not claim resource %s/%d! "
406 "Device offline. Try using e820_host=1 in the guest config.\n",
407 pci_name(dev), i);
408 }
409 }
410 }
411
412 return 0;
413 }
414
415 static int pcifront_scan_bus(struct pcifront_device *pdev,
416 unsigned int domain, unsigned int bus,
417 struct pci_bus *b)
418 {
419 struct pci_dev *d;
420 unsigned int devfn;
421
422 /* Scan the bus for functions and add.
423 * We omit handling of PCI bridge attachment because pciback prevents
424 * bridges from being exported.
425 */
426 for (devfn = 0; devfn < 0x100; devfn++) {
427 d = pci_get_slot(b, devfn);
428 if (d) {
429 /* Device is already known. */
430 pci_dev_put(d);
431 continue;
432 }
433
434 d = pci_scan_single_device(b, devfn);
435 if (d)
436 dev_info(&pdev->xdev->dev, "New device on "
437 "%04x:%02x:%02x.%d found.\n", domain, bus,
438 PCI_SLOT(devfn), PCI_FUNC(devfn));
439 }
440
441 return 0;
442 }
443
444 static int pcifront_scan_root(struct pcifront_device *pdev,
445 unsigned int domain, unsigned int bus)
446 {
447 struct pci_bus *b;
448 struct pcifront_sd *sd = NULL;
449 struct pci_bus_entry *bus_entry = NULL;
450 int err = 0;
451
452 #ifndef CONFIG_PCI_DOMAINS
453 if (domain != 0) {
454 dev_err(&pdev->xdev->dev,
455 "PCI Root in non-zero PCI Domain! domain=%d\n", domain);
456 dev_err(&pdev->xdev->dev,
457 "Please compile with CONFIG_PCI_DOMAINS\n");
458 err = -EINVAL;
459 goto err_out;
460 }
461 #endif
462
463 dev_info(&pdev->xdev->dev, "Creating PCI Frontend Bus %04x:%02x\n",
464 domain, bus);
465
466 bus_entry = kmalloc(sizeof(*bus_entry), GFP_KERNEL);
467 sd = kmalloc(sizeof(*sd), GFP_KERNEL);
468 if (!bus_entry || !sd) {
469 err = -ENOMEM;
470 goto err_out;
471 }
472 pcifront_init_sd(sd, domain, bus, pdev);
473
474 b = pci_scan_bus_parented(&pdev->xdev->dev, bus,
475 &pcifront_bus_ops, sd);
476 if (!b) {
477 dev_err(&pdev->xdev->dev,
478 "Error creating PCI Frontend Bus!\n");
479 err = -ENOMEM;
480 goto err_out;
481 }
482
483 bus_entry->bus = b;
484
485 list_add(&bus_entry->list, &pdev->root_buses);
486
487 /* pci_scan_bus_parented skips devices which do not have a have
488 * devfn==0. The pcifront_scan_bus enumerates all devfn. */
489 err = pcifront_scan_bus(pdev, domain, bus, b);
490
491 /* Claim resources before going "live" with our devices */
492 pci_walk_bus(b, pcifront_claim_resource, pdev);
493
494 /* Create SysFS and notify udev of the devices. Aka: "going live" */
495 pci_bus_add_devices(b);
496
497 return err;
498
499 err_out:
500 kfree(bus_entry);
501 kfree(sd);
502
503 return err;
504 }
505
506 static int pcifront_rescan_root(struct pcifront_device *pdev,
507 unsigned int domain, unsigned int bus)
508 {
509 int err;
510 struct pci_bus *b;
511
512 #ifndef CONFIG_PCI_DOMAINS
513 if (domain != 0) {
514 dev_err(&pdev->xdev->dev,
515 "PCI Root in non-zero PCI Domain! domain=%d\n", domain);
516 dev_err(&pdev->xdev->dev,
517 "Please compile with CONFIG_PCI_DOMAINS\n");
518 return -EINVAL;
519 }
520 #endif
521
522 dev_info(&pdev->xdev->dev, "Rescanning PCI Frontend Bus %04x:%02x\n",
523 domain, bus);
524
525 b = pci_find_bus(domain, bus);
526 if (!b)
527 /* If the bus is unknown, create it. */
528 return pcifront_scan_root(pdev, domain, bus);
529
530 err = pcifront_scan_bus(pdev, domain, bus, b);
531
532 /* Claim resources before going "live" with our devices */
533 pci_walk_bus(b, pcifront_claim_resource, pdev);
534
535 /* Create SysFS and notify udev of the devices. Aka: "going live" */
536 pci_bus_add_devices(b);
537
538 return err;
539 }
540
541 static void free_root_bus_devs(struct pci_bus *bus)
542 {
543 struct pci_dev *dev;
544
545 while (!list_empty(&bus->devices)) {
546 dev = container_of(bus->devices.next, struct pci_dev,
547 bus_list);
548 dev_dbg(&dev->dev, "removing device\n");
549 pci_stop_and_remove_bus_device(dev);
550 }
551 }
552
553 static void pcifront_free_roots(struct pcifront_device *pdev)
554 {
555 struct pci_bus_entry *bus_entry, *t;
556
557 dev_dbg(&pdev->xdev->dev, "cleaning up root buses\n");
558
559 list_for_each_entry_safe(bus_entry, t, &pdev->root_buses, list) {
560 list_del(&bus_entry->list);
561
562 free_root_bus_devs(bus_entry->bus);
563
564 kfree(bus_entry->bus->sysdata);
565
566 device_unregister(bus_entry->bus->bridge);
567 pci_remove_bus(bus_entry->bus);
568
569 kfree(bus_entry);
570 }
571 }
572
573 static pci_ers_result_t pcifront_common_process(int cmd,
574 struct pcifront_device *pdev,
575 pci_channel_state_t state)
576 {
577 pci_ers_result_t result;
578 struct pci_driver *pdrv;
579 int bus = pdev->sh_info->aer_op.bus;
580 int devfn = pdev->sh_info->aer_op.devfn;
581 struct pci_dev *pcidev;
582 int flag = 0;
583
584 dev_dbg(&pdev->xdev->dev,
585 "pcifront AER process: cmd %x (bus:%x, devfn%x)",
586 cmd, bus, devfn);
587 result = PCI_ERS_RESULT_NONE;
588
589 pcidev = pci_get_bus_and_slot(bus, devfn);
590 if (!pcidev || !pcidev->driver) {
591 dev_err(&pdev->xdev->dev, "device or AER driver is NULL\n");
592 if (pcidev)
593 pci_dev_put(pcidev);
594 return result;
595 }
596 pdrv = pcidev->driver;
597
598 if (pdrv) {
599 if (pdrv->err_handler && pdrv->err_handler->error_detected) {
600 dev_dbg(&pcidev->dev,
601 "trying to call AER service\n");
602 if (pcidev) {
603 flag = 1;
604 switch (cmd) {
605 case XEN_PCI_OP_aer_detected:
606 result = pdrv->err_handler->
607 error_detected(pcidev, state);
608 break;
609 case XEN_PCI_OP_aer_mmio:
610 result = pdrv->err_handler->
611 mmio_enabled(pcidev);
612 break;
613 case XEN_PCI_OP_aer_slotreset:
614 result = pdrv->err_handler->
615 slot_reset(pcidev);
616 break;
617 case XEN_PCI_OP_aer_resume:
618 pdrv->err_handler->resume(pcidev);
619 break;
620 default:
621 dev_err(&pdev->xdev->dev,
622 "bad request in aer recovery "
623 "operation!\n");
624
625 }
626 }
627 }
628 }
629 if (!flag)
630 result = PCI_ERS_RESULT_NONE;
631
632 return result;
633 }
634
635
636 static void pcifront_do_aer(struct work_struct *data)
637 {
638 struct pcifront_device *pdev =
639 container_of(data, struct pcifront_device, op_work);
640 int cmd = pdev->sh_info->aer_op.cmd;
641 pci_channel_state_t state =
642 (pci_channel_state_t)pdev->sh_info->aer_op.err;
643
644 /*If a pci_conf op is in progress,
645 we have to wait until it is done before service aer op*/
646 dev_dbg(&pdev->xdev->dev,
647 "pcifront service aer bus %x devfn %x\n",
648 pdev->sh_info->aer_op.bus, pdev->sh_info->aer_op.devfn);
649
650 pdev->sh_info->aer_op.err = pcifront_common_process(cmd, pdev, state);
651
652 /* Post the operation to the guest. */
653 wmb();
654 clear_bit(_XEN_PCIB_active, (unsigned long *)&pdev->sh_info->flags);
655 notify_remote_via_evtchn(pdev->evtchn);
656
657 /*in case of we lost an aer request in four lines time_window*/
658 smp_mb__before_clear_bit();
659 clear_bit(_PDEVB_op_active, &pdev->flags);
660 smp_mb__after_clear_bit();
661
662 schedule_pcifront_aer_op(pdev);
663
664 }
665
666 static irqreturn_t pcifront_handler_aer(int irq, void *dev)
667 {
668 struct pcifront_device *pdev = dev;
669 schedule_pcifront_aer_op(pdev);
670 return IRQ_HANDLED;
671 }
672 static int pcifront_connect_and_init_dma(struct pcifront_device *pdev)
673 {
674 int err = 0;
675
676 spin_lock(&pcifront_dev_lock);
677
678 if (!pcifront_dev) {
679 dev_info(&pdev->xdev->dev, "Installing PCI frontend\n");
680 pcifront_dev = pdev;
681 } else
682 err = -EEXIST;
683
684 spin_unlock(&pcifront_dev_lock);
685
686 if (!err && !swiotlb_nr_tbl()) {
687 err = pci_xen_swiotlb_init_late();
688 if (err)
689 dev_err(&pdev->xdev->dev, "Could not setup SWIOTLB!\n");
690 }
691 return err;
692 }
693
694 static void pcifront_disconnect(struct pcifront_device *pdev)
695 {
696 spin_lock(&pcifront_dev_lock);
697
698 if (pdev == pcifront_dev) {
699 dev_info(&pdev->xdev->dev,
700 "Disconnecting PCI Frontend Buses\n");
701 pcifront_dev = NULL;
702 }
703
704 spin_unlock(&pcifront_dev_lock);
705 }
706 static struct pcifront_device *alloc_pdev(struct xenbus_device *xdev)
707 {
708 struct pcifront_device *pdev;
709
710 pdev = kzalloc(sizeof(struct pcifront_device), GFP_KERNEL);
711 if (pdev == NULL)
712 goto out;
713
714 pdev->sh_info =
715 (struct xen_pci_sharedinfo *)__get_free_page(GFP_KERNEL);
716 if (pdev->sh_info == NULL) {
717 kfree(pdev);
718 pdev = NULL;
719 goto out;
720 }
721 pdev->sh_info->flags = 0;
722
723 /*Flag for registering PV AER handler*/
724 set_bit(_XEN_PCIB_AERHANDLER, (void *)&pdev->sh_info->flags);
725
726 dev_set_drvdata(&xdev->dev, pdev);
727 pdev->xdev = xdev;
728
729 INIT_LIST_HEAD(&pdev->root_buses);
730
731 spin_lock_init(&pdev->sh_info_lock);
732
733 pdev->evtchn = INVALID_EVTCHN;
734 pdev->gnt_ref = INVALID_GRANT_REF;
735 pdev->irq = -1;
736
737 INIT_WORK(&pdev->op_work, pcifront_do_aer);
738
739 dev_dbg(&xdev->dev, "Allocated pdev @ 0x%p pdev->sh_info @ 0x%p\n",
740 pdev, pdev->sh_info);
741 out:
742 return pdev;
743 }
744
745 static void free_pdev(struct pcifront_device *pdev)
746 {
747 dev_dbg(&pdev->xdev->dev, "freeing pdev @ 0x%p\n", pdev);
748
749 pcifront_free_roots(pdev);
750
751 cancel_work_sync(&pdev->op_work);
752
753 if (pdev->irq >= 0)
754 unbind_from_irqhandler(pdev->irq, pdev);
755
756 if (pdev->evtchn != INVALID_EVTCHN)
757 xenbus_free_evtchn(pdev->xdev, pdev->evtchn);
758
759 if (pdev->gnt_ref != INVALID_GRANT_REF)
760 gnttab_end_foreign_access(pdev->gnt_ref, 0 /* r/w page */,
761 (unsigned long)pdev->sh_info);
762 else
763 free_page((unsigned long)pdev->sh_info);
764
765 dev_set_drvdata(&pdev->xdev->dev, NULL);
766
767 kfree(pdev);
768 }
769
770 static int pcifront_publish_info(struct pcifront_device *pdev)
771 {
772 int err = 0;
773 struct xenbus_transaction trans;
774
775 err = xenbus_grant_ring(pdev->xdev, virt_to_mfn(pdev->sh_info));
776 if (err < 0)
777 goto out;
778
779 pdev->gnt_ref = err;
780
781 err = xenbus_alloc_evtchn(pdev->xdev, &pdev->evtchn);
782 if (err)
783 goto out;
784
785 err = bind_evtchn_to_irqhandler(pdev->evtchn, pcifront_handler_aer,
786 0, "pcifront", pdev);
787
788 if (err < 0)
789 return err;
790
791 pdev->irq = err;
792
793 do_publish:
794 err = xenbus_transaction_start(&trans);
795 if (err) {
796 xenbus_dev_fatal(pdev->xdev, err,
797 "Error writing configuration for backend "
798 "(start transaction)");
799 goto out;
800 }
801
802 err = xenbus_printf(trans, pdev->xdev->nodename,
803 "pci-op-ref", "%u", pdev->gnt_ref);
804 if (!err)
805 err = xenbus_printf(trans, pdev->xdev->nodename,
806 "event-channel", "%u", pdev->evtchn);
807 if (!err)
808 err = xenbus_printf(trans, pdev->xdev->nodename,
809 "magic", XEN_PCI_MAGIC);
810
811 if (err) {
812 xenbus_transaction_end(trans, 1);
813 xenbus_dev_fatal(pdev->xdev, err,
814 "Error writing configuration for backend");
815 goto out;
816 } else {
817 err = xenbus_transaction_end(trans, 0);
818 if (err == -EAGAIN)
819 goto do_publish;
820 else if (err) {
821 xenbus_dev_fatal(pdev->xdev, err,
822 "Error completing transaction "
823 "for backend");
824 goto out;
825 }
826 }
827
828 xenbus_switch_state(pdev->xdev, XenbusStateInitialised);
829
830 dev_dbg(&pdev->xdev->dev, "publishing successful!\n");
831
832 out:
833 return err;
834 }
835
836 static int pcifront_try_connect(struct pcifront_device *pdev)
837 {
838 int err = -EFAULT;
839 int i, num_roots, len;
840 char str[64];
841 unsigned int domain, bus;
842
843
844 /* Only connect once */
845 if (xenbus_read_driver_state(pdev->xdev->nodename) !=
846 XenbusStateInitialised)
847 goto out;
848
849 err = pcifront_connect_and_init_dma(pdev);
850 if (err && err != -EEXIST) {
851 xenbus_dev_fatal(pdev->xdev, err,
852 "Error setting up PCI Frontend");
853 goto out;
854 }
855
856 err = xenbus_scanf(XBT_NIL, pdev->xdev->otherend,
857 "root_num", "%d", &num_roots);
858 if (err == -ENOENT) {
859 xenbus_dev_error(pdev->xdev, err,
860 "No PCI Roots found, trying 0000:00");
861 err = pcifront_scan_root(pdev, 0, 0);
862 num_roots = 0;
863 } else if (err != 1) {
864 if (err == 0)
865 err = -EINVAL;
866 xenbus_dev_fatal(pdev->xdev, err,
867 "Error reading number of PCI roots");
868 goto out;
869 }
870
871 for (i = 0; i < num_roots; i++) {
872 len = snprintf(str, sizeof(str), "root-%d", i);
873 if (unlikely(len >= (sizeof(str) - 1))) {
874 err = -ENOMEM;
875 goto out;
876 }
877
878 err = xenbus_scanf(XBT_NIL, pdev->xdev->otherend, str,
879 "%x:%x", &domain, &bus);
880 if (err != 2) {
881 if (err >= 0)
882 err = -EINVAL;
883 xenbus_dev_fatal(pdev->xdev, err,
884 "Error reading PCI root %d", i);
885 goto out;
886 }
887
888 err = pcifront_scan_root(pdev, domain, bus);
889 if (err) {
890 xenbus_dev_fatal(pdev->xdev, err,
891 "Error scanning PCI root %04x:%02x",
892 domain, bus);
893 goto out;
894 }
895 }
896
897 err = xenbus_switch_state(pdev->xdev, XenbusStateConnected);
898
899 out:
900 return err;
901 }
902
903 static int pcifront_try_disconnect(struct pcifront_device *pdev)
904 {
905 int err = 0;
906 enum xenbus_state prev_state;
907
908
909 prev_state = xenbus_read_driver_state(pdev->xdev->nodename);
910
911 if (prev_state >= XenbusStateClosing)
912 goto out;
913
914 if (prev_state == XenbusStateConnected) {
915 pcifront_free_roots(pdev);
916 pcifront_disconnect(pdev);
917 }
918
919 err = xenbus_switch_state(pdev->xdev, XenbusStateClosed);
920
921 out:
922
923 return err;
924 }
925
926 static int pcifront_attach_devices(struct pcifront_device *pdev)
927 {
928 int err = -EFAULT;
929 int i, num_roots, len;
930 unsigned int domain, bus;
931 char str[64];
932
933 if (xenbus_read_driver_state(pdev->xdev->nodename) !=
934 XenbusStateReconfiguring)
935 goto out;
936
937 err = xenbus_scanf(XBT_NIL, pdev->xdev->otherend,
938 "root_num", "%d", &num_roots);
939 if (err == -ENOENT) {
940 xenbus_dev_error(pdev->xdev, err,
941 "No PCI Roots found, trying 0000:00");
942 err = pcifront_rescan_root(pdev, 0, 0);
943 num_roots = 0;
944 } else if (err != 1) {
945 if (err == 0)
946 err = -EINVAL;
947 xenbus_dev_fatal(pdev->xdev, err,
948 "Error reading number of PCI roots");
949 goto out;
950 }
951
952 for (i = 0; i < num_roots; i++) {
953 len = snprintf(str, sizeof(str), "root-%d", i);
954 if (unlikely(len >= (sizeof(str) - 1))) {
955 err = -ENOMEM;
956 goto out;
957 }
958
959 err = xenbus_scanf(XBT_NIL, pdev->xdev->otherend, str,
960 "%x:%x", &domain, &bus);
961 if (err != 2) {
962 if (err >= 0)
963 err = -EINVAL;
964 xenbus_dev_fatal(pdev->xdev, err,
965 "Error reading PCI root %d", i);
966 goto out;
967 }
968
969 err = pcifront_rescan_root(pdev, domain, bus);
970 if (err) {
971 xenbus_dev_fatal(pdev->xdev, err,
972 "Error scanning PCI root %04x:%02x",
973 domain, bus);
974 goto out;
975 }
976 }
977
978 xenbus_switch_state(pdev->xdev, XenbusStateConnected);
979
980 out:
981 return err;
982 }
983
984 static int pcifront_detach_devices(struct pcifront_device *pdev)
985 {
986 int err = 0;
987 int i, num_devs;
988 unsigned int domain, bus, slot, func;
989 struct pci_dev *pci_dev;
990 char str[64];
991
992 if (xenbus_read_driver_state(pdev->xdev->nodename) !=
993 XenbusStateConnected)
994 goto out;
995
996 err = xenbus_scanf(XBT_NIL, pdev->xdev->otherend, "num_devs", "%d",
997 &num_devs);
998 if (err != 1) {
999 if (err >= 0)
1000 err = -EINVAL;
1001 xenbus_dev_fatal(pdev->xdev, err,
1002 "Error reading number of PCI devices");
1003 goto out;
1004 }
1005
1006 /* Find devices being detached and remove them. */
1007 for (i = 0; i < num_devs; i++) {
1008 int l, state;
1009 l = snprintf(str, sizeof(str), "state-%d", i);
1010 if (unlikely(l >= (sizeof(str) - 1))) {
1011 err = -ENOMEM;
1012 goto out;
1013 }
1014 err = xenbus_scanf(XBT_NIL, pdev->xdev->otherend, str, "%d",
1015 &state);
1016 if (err != 1)
1017 state = XenbusStateUnknown;
1018
1019 if (state != XenbusStateClosing)
1020 continue;
1021
1022 /* Remove device. */
1023 l = snprintf(str, sizeof(str), "vdev-%d", i);
1024 if (unlikely(l >= (sizeof(str) - 1))) {
1025 err = -ENOMEM;
1026 goto out;
1027 }
1028 err = xenbus_scanf(XBT_NIL, pdev->xdev->otherend, str,
1029 "%x:%x:%x.%x", &domain, &bus, &slot, &func);
1030 if (err != 4) {
1031 if (err >= 0)
1032 err = -EINVAL;
1033 xenbus_dev_fatal(pdev->xdev, err,
1034 "Error reading PCI device %d", i);
1035 goto out;
1036 }
1037
1038 pci_dev = pci_get_domain_bus_and_slot(domain, bus,
1039 PCI_DEVFN(slot, func));
1040 if (!pci_dev) {
1041 dev_dbg(&pdev->xdev->dev,
1042 "Cannot get PCI device %04x:%02x:%02x.%d\n",
1043 domain, bus, slot, func);
1044 continue;
1045 }
1046 pci_stop_and_remove_bus_device(pci_dev);
1047 pci_dev_put(pci_dev);
1048
1049 dev_dbg(&pdev->xdev->dev,
1050 "PCI device %04x:%02x:%02x.%d removed.\n",
1051 domain, bus, slot, func);
1052 }
1053
1054 err = xenbus_switch_state(pdev->xdev, XenbusStateReconfiguring);
1055
1056 out:
1057 return err;
1058 }
1059
1060 static void __init_refok pcifront_backend_changed(struct xenbus_device *xdev,
1061 enum xenbus_state be_state)
1062 {
1063 struct pcifront_device *pdev = dev_get_drvdata(&xdev->dev);
1064
1065 switch (be_state) {
1066 case XenbusStateUnknown:
1067 case XenbusStateInitialising:
1068 case XenbusStateInitWait:
1069 case XenbusStateInitialised:
1070 break;
1071
1072 case XenbusStateConnected:
1073 pcifront_try_connect(pdev);
1074 break;
1075
1076 case XenbusStateClosed:
1077 if (xdev->state == XenbusStateClosed)
1078 break;
1079 /* Missed the backend's CLOSING state -- fallthrough */
1080 case XenbusStateClosing:
1081 dev_warn(&xdev->dev, "backend going away!\n");
1082 pcifront_try_disconnect(pdev);
1083 break;
1084
1085 case XenbusStateReconfiguring:
1086 pcifront_detach_devices(pdev);
1087 break;
1088
1089 case XenbusStateReconfigured:
1090 pcifront_attach_devices(pdev);
1091 break;
1092 }
1093 }
1094
1095 static int pcifront_xenbus_probe(struct xenbus_device *xdev,
1096 const struct xenbus_device_id *id)
1097 {
1098 int err = 0;
1099 struct pcifront_device *pdev = alloc_pdev(xdev);
1100
1101 if (pdev == NULL) {
1102 err = -ENOMEM;
1103 xenbus_dev_fatal(xdev, err,
1104 "Error allocating pcifront_device struct");
1105 goto out;
1106 }
1107
1108 err = pcifront_publish_info(pdev);
1109 if (err)
1110 free_pdev(pdev);
1111
1112 out:
1113 return err;
1114 }
1115
1116 static int pcifront_xenbus_remove(struct xenbus_device *xdev)
1117 {
1118 struct pcifront_device *pdev = dev_get_drvdata(&xdev->dev);
1119 if (pdev)
1120 free_pdev(pdev);
1121
1122 return 0;
1123 }
1124
1125 static const struct xenbus_device_id xenpci_ids[] = {
1126 {"pci"},
1127 {""},
1128 };
1129
1130 static DEFINE_XENBUS_DRIVER(xenpci, "pcifront",
1131 .probe = pcifront_xenbus_probe,
1132 .remove = pcifront_xenbus_remove,
1133 .otherend_changed = pcifront_backend_changed,
1134 );
1135
1136 static int __init pcifront_init(void)
1137 {
1138 if (!xen_pv_domain() || xen_initial_domain())
1139 return -ENODEV;
1140
1141 pci_frontend_registrar(1 /* enable */);
1142
1143 return xenbus_register_frontend(&xenpci_driver);
1144 }
1145
1146 static void __exit pcifront_cleanup(void)
1147 {
1148 xenbus_unregister_driver(&xenpci_driver);
1149 pci_frontend_registrar(0 /* disable */);
1150 }
1151 module_init(pcifront_init);
1152 module_exit(pcifront_cleanup);
1153
1154 MODULE_DESCRIPTION("Xen PCI passthrough frontend.");
1155 MODULE_LICENSE("GPL");
1156 MODULE_ALIAS("xen:pci");
kernel source for telekom puls (alcatel/mediatek)