blob: 966abc6054d7b625c18a5eeb854dc065b40d43c1 [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 Sharma600634972011-07-26 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
Konrad Rzeszutek Wilk3d925322012-07-31 06:26:59 -040024#include <asm/xen/swiotlb-xen.h>
Ryan Wilson956a9202010-08-02 21:31:05 -040025#define INVALID_GRANT_REF (0)
26#define INVALID_EVTCHN (-1)
27
28struct 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
36struct 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
53struct pcifront_sd {
54 int domain;
55 struct pcifront_device *pdev;
56};
57
58static inline struct pcifront_device *
59pcifront_get_pdev(struct pcifront_sd *sd)
60{
61 return sd->pdev;
62}
63
64static 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
72static DEFINE_SPINLOCK(pcifront_dev_lock);
73static struct pcifront_device *pcifront_dev;
74
75static int verbose_request;
76module_param(verbose_request, int, 0644);
77
78static 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
100static 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
109static 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;
170out:
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 */
176static 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,
Konrad Rzeszutek Wilke4de8662012-01-25 16:00:00 -0500193 "read dev=%04x:%02x:%02x.%d - offset %x size %d\n",
Ryan Wilson956a9202010-08-02 21:31:05 -0400194 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 */
215static 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,
Konrad Rzeszutek Wilke4de8662012-01-25 16:00:00 -0500232 "write dev=%04x:%02x:%02x.%d - "
Ryan Wilson956a9202010-08-02 21:31:05 -0400233 "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
Konrad Rzeszutek Wilkb8b0f552012-08-21 14:49:34 -0400240static struct pci_ops pcifront_bus_ops = {
Ryan Wilson956a9202010-08-02 21:31:05 -0400241 .read = pcifront_bus_read,
242 .write = pcifront_bus_write,
243};
244
245#ifdef CONFIG_PCI_MSI
246static int pci_frontend_enable_msix(struct pci_dev *dev,
Konrad Rzeszutek Wilkcc0f89c2011-02-17 12:02:23 -0500247 int vector[], int nvec)
Ryan Wilson956a9202010-08-02 21:31:05 -0400248{
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 */
Konrad Rzeszutek Wilk1d461052011-02-16 13:43:22 -0500281 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;
Konrad Rzeszutek Wilkcc0f89c2011-02-17 12:02:23 -0500286 vector[i] = -1;
Konrad Rzeszutek Wilk1d461052011-02-16 13:43:22 -0500287 continue;
288 }
Konrad Rzeszutek Wilkcc0f89c2011-02-17 12:02:23 -0500289 vector[i] = op.msix_entries[i].vector;
Konrad Rzeszutek Wilk1d461052011-02-16 13:43:22 -0500290 }
Ryan Wilson956a9202010-08-02 21:31:05 -0400291 } else {
292 printk(KERN_DEBUG "enable msix get value %x\n",
293 op.value);
Jan Beulichf09d8432012-04-02 15:22:39 +0100294 err = op.value;
Ryan Wilson956a9202010-08-02 21:31:05 -0400295 }
296 } else {
297 dev_err(&dev->dev, "enable msix get err %x\n", err);
Ryan Wilson956a9202010-08-02 21:31:05 -0400298 }
Konrad Rzeszutek Wilk1d461052011-02-16 13:43:22 -0500299 return err;
Ryan Wilson956a9202010-08-02 21:31:05 -0400300}
301
302static 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
Konrad Rzeszutek Wilkcc0f89c2011-02-17 12:02:23 -0500321static int pci_frontend_enable_msi(struct pci_dev *dev, int vector[])
Ryan Wilson956a9202010-08-02 21:31:05 -0400322{
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)) {
Konrad Rzeszutek Wilkcc0f89c2011-02-17 12:02:23 -0500335 vector[0] = op.value;
Konrad Rzeszutek Wilk1d461052011-02-16 13:43:22 -0500336 if (op.value <= 0) {
337 dev_warn(&dev->dev, "MSI entry is invalid: %d!\n",
338 op.value);
339 err = -EINVAL;
Konrad Rzeszutek Wilkcc0f89c2011-02-17 12:02:23 -0500340 vector[0] = -1;
Konrad Rzeszutek Wilk1d461052011-02-16 13:43:22 -0500341 }
Ryan Wilson956a9202010-08-02 21:31:05 -0400342 } 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
350static 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
373static 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
380static 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
388static 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 */
392static 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)) {
Konrad Rzeszutek Wilk917e3e62011-07-22 12:18:43 -0400405 dev_err(&pdev->xdev->dev, "Could not claim resource %s/%d! "
406 "Device offline. Try using e820_host=1 in the guest config.\n",
Ryan Wilson956a9202010-08-02 21:31:05 -0400407 pci_name(dev), i);
408 }
409 }
410 }
411
412 return 0;
413}
414
Bill Pemberton15856ad2012-11-21 15:35:00 -0500415static int pcifront_scan_bus(struct pcifront_device *pdev,
Ryan Wilson956a9202010-08-02 21:31:05 -0400416 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 "
Konrad Rzeszutek Wilke4de8662012-01-25 16:00:00 -0500437 "%04x:%02x:%02x.%d found.\n", domain, bus,
Ryan Wilson956a9202010-08-02 21:31:05 -0400438 PCI_SLOT(devfn), PCI_FUNC(devfn));
439 }
440
441 return 0;
442}
443
Bill Pemberton15856ad2012-11-21 15:35:00 -0500444static int pcifront_scan_root(struct pcifront_device *pdev,
Ryan Wilson956a9202010-08-02 21:31:05 -0400445 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
499err_out:
500 kfree(bus_entry);
501 kfree(sd);
502
503 return err;
504}
505
Bill Pemberton15856ad2012-11-21 15:35:00 -0500506static int pcifront_rescan_root(struct pcifront_device *pdev,
Ryan Wilson956a9202010-08-02 21:31:05 -0400507 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
541static 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");
Yinghai Lu210647a2012-02-25 13:54:20 -0800549 pci_stop_and_remove_bus_device(dev);
Ryan Wilson956a9202010-08-02 21:31:05 -0400550 }
551}
552
553static 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
573static 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) {
Jiri Slaby2a63dd72010-11-04 15:31:30 +0100591 dev_err(&pdev->xdev->dev, "device or AER driver is NULL\n");
592 if (pcidev)
593 pci_dev_put(pcidev);
Ryan Wilson956a9202010-08-02 21:31:05 -0400594 return result;
595 }
596 pdrv = pcidev->driver;
597
Alan Stern07d25142012-01-27 10:24:40 -0500598 if (pdrv) {
Ryan Wilson956a9202010-08-02 21:31:05 -0400599 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 }
Ryan Wilson956a9202010-08-02 21:31:05 -0400628 }
629 if (!flag)
630 result = PCI_ERS_RESULT_NONE;
631
632 return result;
633}
634
635
636static 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
666static 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}
Konrad Rzeszutek Wilk3d925322012-07-31 06:26:59 -0400672static int pcifront_connect_and_init_dma(struct pcifront_device *pdev)
Ryan Wilson956a9202010-08-02 21:31:05 -0400673{
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 dev_err(&pdev->xdev->dev, "PCI frontend already installed!\n");
683 err = -EEXIST;
684 }
Ryan Wilson956a9202010-08-02 21:31:05 -0400685 spin_unlock(&pcifront_dev_lock);
686
Konrad Rzeszutek Wilk3d925322012-07-31 06:26:59 -0400687 if (!err && !swiotlb_nr_tbl()) {
688 err = pci_xen_swiotlb_init_late();
689 if (err)
690 dev_err(&pdev->xdev->dev, "Could not setup SWIOTLB!\n");
691 }
Ryan Wilson956a9202010-08-02 21:31:05 -0400692 return err;
693}
694
695static void pcifront_disconnect(struct pcifront_device *pdev)
696{
697 spin_lock(&pcifront_dev_lock);
698
699 if (pdev == pcifront_dev) {
700 dev_info(&pdev->xdev->dev,
701 "Disconnecting PCI Frontend Buses\n");
702 pcifront_dev = NULL;
703 }
704
705 spin_unlock(&pcifront_dev_lock);
706}
707static struct pcifront_device *alloc_pdev(struct xenbus_device *xdev)
708{
709 struct pcifront_device *pdev;
710
711 pdev = kzalloc(sizeof(struct pcifront_device), GFP_KERNEL);
712 if (pdev == NULL)
713 goto out;
714
715 pdev->sh_info =
716 (struct xen_pci_sharedinfo *)__get_free_page(GFP_KERNEL);
717 if (pdev->sh_info == NULL) {
718 kfree(pdev);
719 pdev = NULL;
720 goto out;
721 }
722 pdev->sh_info->flags = 0;
723
724 /*Flag for registering PV AER handler*/
725 set_bit(_XEN_PCIB_AERHANDLER, (void *)&pdev->sh_info->flags);
726
727 dev_set_drvdata(&xdev->dev, pdev);
728 pdev->xdev = xdev;
729
730 INIT_LIST_HEAD(&pdev->root_buses);
731
732 spin_lock_init(&pdev->sh_info_lock);
733
734 pdev->evtchn = INVALID_EVTCHN;
735 pdev->gnt_ref = INVALID_GRANT_REF;
736 pdev->irq = -1;
737
738 INIT_WORK(&pdev->op_work, pcifront_do_aer);
739
740 dev_dbg(&xdev->dev, "Allocated pdev @ 0x%p pdev->sh_info @ 0x%p\n",
741 pdev, pdev->sh_info);
742out:
743 return pdev;
744}
745
746static void free_pdev(struct pcifront_device *pdev)
747{
748 dev_dbg(&pdev->xdev->dev, "freeing pdev @ 0x%p\n", pdev);
749
750 pcifront_free_roots(pdev);
751
Tejun Heodb2e2e62011-01-24 15:43:03 +0100752 cancel_work_sync(&pdev->op_work);
Ryan Wilson956a9202010-08-02 21:31:05 -0400753
754 if (pdev->irq >= 0)
755 unbind_from_irqhandler(pdev->irq, pdev);
756
757 if (pdev->evtchn != INVALID_EVTCHN)
758 xenbus_free_evtchn(pdev->xdev, pdev->evtchn);
759
760 if (pdev->gnt_ref != INVALID_GRANT_REF)
761 gnttab_end_foreign_access(pdev->gnt_ref, 0 /* r/w page */,
762 (unsigned long)pdev->sh_info);
763 else
764 free_page((unsigned long)pdev->sh_info);
765
766 dev_set_drvdata(&pdev->xdev->dev, NULL);
767
768 kfree(pdev);
769}
770
771static int pcifront_publish_info(struct pcifront_device *pdev)
772{
773 int err = 0;
774 struct xenbus_transaction trans;
775
776 err = xenbus_grant_ring(pdev->xdev, virt_to_mfn(pdev->sh_info));
777 if (err < 0)
778 goto out;
779
780 pdev->gnt_ref = err;
781
782 err = xenbus_alloc_evtchn(pdev->xdev, &pdev->evtchn);
783 if (err)
784 goto out;
785
786 err = bind_evtchn_to_irqhandler(pdev->evtchn, pcifront_handler_aer,
787 0, "pcifront", pdev);
788
789 if (err < 0)
790 return err;
791
792 pdev->irq = err;
793
794do_publish:
795 err = xenbus_transaction_start(&trans);
796 if (err) {
797 xenbus_dev_fatal(pdev->xdev, err,
798 "Error writing configuration for backend "
799 "(start transaction)");
800 goto out;
801 }
802
803 err = xenbus_printf(trans, pdev->xdev->nodename,
804 "pci-op-ref", "%u", pdev->gnt_ref);
805 if (!err)
806 err = xenbus_printf(trans, pdev->xdev->nodename,
807 "event-channel", "%u", pdev->evtchn);
808 if (!err)
809 err = xenbus_printf(trans, pdev->xdev->nodename,
810 "magic", XEN_PCI_MAGIC);
811
812 if (err) {
813 xenbus_transaction_end(trans, 1);
814 xenbus_dev_fatal(pdev->xdev, err,
815 "Error writing configuration for backend");
816 goto out;
817 } else {
818 err = xenbus_transaction_end(trans, 0);
819 if (err == -EAGAIN)
820 goto do_publish;
821 else if (err) {
822 xenbus_dev_fatal(pdev->xdev, err,
823 "Error completing transaction "
824 "for backend");
825 goto out;
826 }
827 }
828
829 xenbus_switch_state(pdev->xdev, XenbusStateInitialised);
830
831 dev_dbg(&pdev->xdev->dev, "publishing successful!\n");
832
833out:
834 return err;
835}
836
Bill Pemberton15856ad2012-11-21 15:35:00 -0500837static int pcifront_try_connect(struct pcifront_device *pdev)
Ryan Wilson956a9202010-08-02 21:31:05 -0400838{
839 int err = -EFAULT;
840 int i, num_roots, len;
841 char str[64];
842 unsigned int domain, bus;
843
844
845 /* Only connect once */
846 if (xenbus_read_driver_state(pdev->xdev->nodename) !=
847 XenbusStateInitialised)
848 goto out;
849
Konrad Rzeszutek Wilk3d925322012-07-31 06:26:59 -0400850 err = pcifront_connect_and_init_dma(pdev);
Ryan Wilson956a9202010-08-02 21:31:05 -0400851 if (err) {
852 xenbus_dev_fatal(pdev->xdev, err,
Konrad Rzeszutek Wilk3d925322012-07-31 06:26:59 -0400853 "Error setting up PCI Frontend");
Ryan Wilson956a9202010-08-02 21:31:05 -0400854 goto out;
855 }
856
857 err = xenbus_scanf(XBT_NIL, pdev->xdev->otherend,
858 "root_num", "%d", &num_roots);
859 if (err == -ENOENT) {
860 xenbus_dev_error(pdev->xdev, err,
861 "No PCI Roots found, trying 0000:00");
862 err = pcifront_scan_root(pdev, 0, 0);
863 num_roots = 0;
864 } else if (err != 1) {
865 if (err == 0)
866 err = -EINVAL;
867 xenbus_dev_fatal(pdev->xdev, err,
868 "Error reading number of PCI roots");
869 goto out;
870 }
871
872 for (i = 0; i < num_roots; i++) {
873 len = snprintf(str, sizeof(str), "root-%d", i);
874 if (unlikely(len >= (sizeof(str) - 1))) {
875 err = -ENOMEM;
876 goto out;
877 }
878
879 err = xenbus_scanf(XBT_NIL, pdev->xdev->otherend, str,
880 "%x:%x", &domain, &bus);
881 if (err != 2) {
882 if (err >= 0)
883 err = -EINVAL;
884 xenbus_dev_fatal(pdev->xdev, err,
885 "Error reading PCI root %d", i);
886 goto out;
887 }
888
889 err = pcifront_scan_root(pdev, domain, bus);
890 if (err) {
891 xenbus_dev_fatal(pdev->xdev, err,
892 "Error scanning PCI root %04x:%02x",
893 domain, bus);
894 goto out;
895 }
896 }
897
898 err = xenbus_switch_state(pdev->xdev, XenbusStateConnected);
899
900out:
901 return err;
902}
903
904static int pcifront_try_disconnect(struct pcifront_device *pdev)
905{
906 int err = 0;
907 enum xenbus_state prev_state;
908
909
910 prev_state = xenbus_read_driver_state(pdev->xdev->nodename);
911
912 if (prev_state >= XenbusStateClosing)
913 goto out;
914
915 if (prev_state == XenbusStateConnected) {
916 pcifront_free_roots(pdev);
917 pcifront_disconnect(pdev);
918 }
919
920 err = xenbus_switch_state(pdev->xdev, XenbusStateClosed);
921
922out:
923
924 return err;
925}
926
Bill Pemberton15856ad2012-11-21 15:35:00 -0500927static int pcifront_attach_devices(struct pcifront_device *pdev)
Ryan Wilson956a9202010-08-02 21:31:05 -0400928{
929 int err = -EFAULT;
930 int i, num_roots, len;
931 unsigned int domain, bus;
932 char str[64];
933
934 if (xenbus_read_driver_state(pdev->xdev->nodename) !=
935 XenbusStateReconfiguring)
936 goto out;
937
938 err = xenbus_scanf(XBT_NIL, pdev->xdev->otherend,
939 "root_num", "%d", &num_roots);
940 if (err == -ENOENT) {
941 xenbus_dev_error(pdev->xdev, err,
942 "No PCI Roots found, trying 0000:00");
943 err = pcifront_rescan_root(pdev, 0, 0);
944 num_roots = 0;
945 } else if (err != 1) {
946 if (err == 0)
947 err = -EINVAL;
948 xenbus_dev_fatal(pdev->xdev, err,
949 "Error reading number of PCI roots");
950 goto out;
951 }
952
953 for (i = 0; i < num_roots; i++) {
954 len = snprintf(str, sizeof(str), "root-%d", i);
955 if (unlikely(len >= (sizeof(str) - 1))) {
956 err = -ENOMEM;
957 goto out;
958 }
959
960 err = xenbus_scanf(XBT_NIL, pdev->xdev->otherend, str,
961 "%x:%x", &domain, &bus);
962 if (err != 2) {
963 if (err >= 0)
964 err = -EINVAL;
965 xenbus_dev_fatal(pdev->xdev, err,
966 "Error reading PCI root %d", i);
967 goto out;
968 }
969
970 err = pcifront_rescan_root(pdev, domain, bus);
971 if (err) {
972 xenbus_dev_fatal(pdev->xdev, err,
973 "Error scanning PCI root %04x:%02x",
974 domain, bus);
975 goto out;
976 }
977 }
978
979 xenbus_switch_state(pdev->xdev, XenbusStateConnected);
980
981out:
982 return err;
983}
984
985static int pcifront_detach_devices(struct pcifront_device *pdev)
986{
987 int err = 0;
988 int i, num_devs;
989 unsigned int domain, bus, slot, func;
Ryan Wilson956a9202010-08-02 21:31:05 -0400990 struct pci_dev *pci_dev;
991 char str[64];
992
993 if (xenbus_read_driver_state(pdev->xdev->nodename) !=
994 XenbusStateConnected)
995 goto out;
996
997 err = xenbus_scanf(XBT_NIL, pdev->xdev->otherend, "num_devs", "%d",
998 &num_devs);
999 if (err != 1) {
1000 if (err >= 0)
1001 err = -EINVAL;
1002 xenbus_dev_fatal(pdev->xdev, err,
1003 "Error reading number of PCI devices");
1004 goto out;
1005 }
1006
1007 /* Find devices being detached and remove them. */
1008 for (i = 0; i < num_devs; i++) {
1009 int l, state;
1010 l = snprintf(str, sizeof(str), "state-%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, "%d",
1016 &state);
1017 if (err != 1)
1018 state = XenbusStateUnknown;
1019
1020 if (state != XenbusStateClosing)
1021 continue;
1022
1023 /* Remove device. */
1024 l = snprintf(str, sizeof(str), "vdev-%d", i);
1025 if (unlikely(l >= (sizeof(str) - 1))) {
1026 err = -ENOMEM;
1027 goto out;
1028 }
1029 err = xenbus_scanf(XBT_NIL, pdev->xdev->otherend, str,
1030 "%x:%x:%x.%x", &domain, &bus, &slot, &func);
1031 if (err != 4) {
1032 if (err >= 0)
1033 err = -EINVAL;
1034 xenbus_dev_fatal(pdev->xdev, err,
1035 "Error reading PCI device %d", i);
1036 goto out;
1037 }
1038
Jiang Liu2ccc2462012-08-28 23:43:58 +08001039 pci_dev = pci_get_domain_bus_and_slot(domain, bus,
1040 PCI_DEVFN(slot, func));
Ryan Wilson956a9202010-08-02 21:31:05 -04001041 if (!pci_dev) {
1042 dev_dbg(&pdev->xdev->dev,
Konrad Rzeszutek Wilke4de8662012-01-25 16:00:00 -05001043 "Cannot get PCI device %04x:%02x:%02x.%d\n",
Ryan Wilson956a9202010-08-02 21:31:05 -04001044 domain, bus, slot, func);
1045 continue;
1046 }
Yinghai Lu210647a2012-02-25 13:54:20 -08001047 pci_stop_and_remove_bus_device(pci_dev);
Ryan Wilson956a9202010-08-02 21:31:05 -04001048 pci_dev_put(pci_dev);
1049
1050 dev_dbg(&pdev->xdev->dev,
Konrad Rzeszutek Wilke4de8662012-01-25 16:00:00 -05001051 "PCI device %04x:%02x:%02x.%d removed.\n",
Ryan Wilson956a9202010-08-02 21:31:05 -04001052 domain, bus, slot, func);
1053 }
1054
1055 err = xenbus_switch_state(pdev->xdev, XenbusStateReconfiguring);
1056
1057out:
1058 return err;
1059}
1060
1061static void __init_refok pcifront_backend_changed(struct xenbus_device *xdev,
1062 enum xenbus_state be_state)
1063{
1064 struct pcifront_device *pdev = dev_get_drvdata(&xdev->dev);
1065
1066 switch (be_state) {
1067 case XenbusStateUnknown:
1068 case XenbusStateInitialising:
1069 case XenbusStateInitWait:
1070 case XenbusStateInitialised:
Ryan Wilson956a9202010-08-02 21:31:05 -04001071 break;
1072
1073 case XenbusStateConnected:
1074 pcifront_try_connect(pdev);
1075 break;
1076
David Vrabeld5af64d2012-10-18 11:03:36 +01001077 case XenbusStateClosed:
1078 if (xdev->state == XenbusStateClosed)
1079 break;
1080 /* Missed the backend's CLOSING state -- fallthrough */
Ryan Wilson956a9202010-08-02 21:31:05 -04001081 case XenbusStateClosing:
1082 dev_warn(&xdev->dev, "backend going away!\n");
1083 pcifront_try_disconnect(pdev);
1084 break;
1085
1086 case XenbusStateReconfiguring:
1087 pcifront_detach_devices(pdev);
1088 break;
1089
1090 case XenbusStateReconfigured:
1091 pcifront_attach_devices(pdev);
1092 break;
1093 }
1094}
1095
1096static int pcifront_xenbus_probe(struct xenbus_device *xdev,
1097 const struct xenbus_device_id *id)
1098{
1099 int err = 0;
1100 struct pcifront_device *pdev = alloc_pdev(xdev);
1101
1102 if (pdev == NULL) {
1103 err = -ENOMEM;
1104 xenbus_dev_fatal(xdev, err,
1105 "Error allocating pcifront_device struct");
1106 goto out;
1107 }
1108
1109 err = pcifront_publish_info(pdev);
1110 if (err)
1111 free_pdev(pdev);
1112
1113out:
1114 return err;
1115}
1116
1117static int pcifront_xenbus_remove(struct xenbus_device *xdev)
1118{
1119 struct pcifront_device *pdev = dev_get_drvdata(&xdev->dev);
1120 if (pdev)
1121 free_pdev(pdev);
1122
1123 return 0;
1124}
1125
1126static const struct xenbus_device_id xenpci_ids[] = {
1127 {"pci"},
1128 {""},
1129};
1130
Jan Beulich73db1442011-12-22 09:08:13 +00001131static DEFINE_XENBUS_DRIVER(xenpci, "pcifront",
Ryan Wilson956a9202010-08-02 21:31:05 -04001132 .probe = pcifront_xenbus_probe,
1133 .remove = pcifront_xenbus_remove,
1134 .otherend_changed = pcifront_backend_changed,
Jan Beulich73db1442011-12-22 09:08:13 +00001135);
Ryan Wilson956a9202010-08-02 21:31:05 -04001136
1137static int __init pcifront_init(void)
1138{
1139 if (!xen_pv_domain() || xen_initial_domain())
1140 return -ENODEV;
1141
1142 pci_frontend_registrar(1 /* enable */);
1143
Jan Beulich73db1442011-12-22 09:08:13 +00001144 return xenbus_register_frontend(&xenpci_driver);
Ryan Wilson956a9202010-08-02 21:31:05 -04001145}
1146
1147static void __exit pcifront_cleanup(void)
1148{
Jan Beulich73db1442011-12-22 09:08:13 +00001149 xenbus_unregister_driver(&xenpci_driver);
Ryan Wilson956a9202010-08-02 21:31:05 -04001150 pci_frontend_registrar(0 /* disable */);
1151}
1152module_init(pcifront_init);
1153module_exit(pcifront_cleanup);
1154
1155MODULE_DESCRIPTION("Xen PCI passthrough frontend.");
1156MODULE_LICENSE("GPL");
1157MODULE_ALIAS("xen:pci");