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33#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
34#define dev_fmt pr_fmt
35
36#define DPRINTK(fmt, args...) \
37 pr_debug("xenbus_probe (%s:%d) " fmt ".\n", \
38 __func__, __LINE__, ##args)
39
40#include <linux/kernel.h>
41#include <linux/err.h>
42#include <linux/string.h>
43#include <linux/ctype.h>
44#include <linux/fcntl.h>
45#include <linux/mm.h>
46#include <linux/proc_fs.h>
47#include <linux/notifier.h>
48#include <linux/kthread.h>
49#include <linux/mutex.h>
50#include <linux/io.h>
51#include <linux/slab.h>
52#include <linux/module.h>
53
54#include <asm/page.h>
55#include <asm/xen/hypervisor.h>
56
57#include <xen/xen.h>
58#include <xen/xenbus.h>
59#include <xen/events.h>
60#include <xen/xen-ops.h>
61#include <xen/page.h>
62
63#include <xen/hvm.h>
64
65#include "xenbus.h"
66
67
68int xen_store_evtchn;
69EXPORT_SYMBOL_GPL(xen_store_evtchn);
70
71struct xenstore_domain_interface *xen_store_interface;
72EXPORT_SYMBOL_GPL(xen_store_interface);
73
74enum xenstore_init xen_store_domain_type;
75EXPORT_SYMBOL_GPL(xen_store_domain_type);
76
77static unsigned long xen_store_gfn;
78
79static BLOCKING_NOTIFIER_HEAD(xenstore_chain);
80
81
82static const struct xenbus_device_id *
83match_device(const struct xenbus_device_id *arr, struct xenbus_device *dev)
84{
85 for (; *arr->devicetype != '\0'; arr++) {
86 if (!strcmp(arr->devicetype, dev->devicetype))
87 return arr;
88 }
89 return NULL;
90}
91
92int xenbus_match(struct device *_dev, struct device_driver *_drv)
93{
94 struct xenbus_driver *drv = to_xenbus_driver(_drv);
95
96 if (!drv->ids)
97 return 0;
98
99 return match_device(drv->ids, to_xenbus_device(_dev)) != NULL;
100}
101EXPORT_SYMBOL_GPL(xenbus_match);
102
103
104static void free_otherend_details(struct xenbus_device *dev)
105{
106 kfree(dev->otherend);
107 dev->otherend = NULL;
108}
109
110
111static void free_otherend_watch(struct xenbus_device *dev)
112{
113 if (dev->otherend_watch.node) {
114 unregister_xenbus_watch(&dev->otherend_watch);
115 kfree(dev->otherend_watch.node);
116 dev->otherend_watch.node = NULL;
117 }
118}
119
120
121static int talk_to_otherend(struct xenbus_device *dev)
122{
123 struct xenbus_driver *drv = to_xenbus_driver(dev->dev.driver);
124
125 free_otherend_watch(dev);
126 free_otherend_details(dev);
127
128 return drv->read_otherend_details(dev);
129}
130
131
132
133static int watch_otherend(struct xenbus_device *dev)
134{
135 struct xen_bus_type *bus =
136 container_of(dev->dev.bus, struct xen_bus_type, bus);
137
138 return xenbus_watch_pathfmt(dev, &dev->otherend_watch,
139 bus->otherend_will_handle,
140 bus->otherend_changed,
141 "%s/%s", dev->otherend, "state");
142}
143
144
145int xenbus_read_otherend_details(struct xenbus_device *xendev,
146 char *id_node, char *path_node)
147{
148 int err = xenbus_gather(XBT_NIL, xendev->nodename,
149 id_node, "%i", &xendev->otherend_id,
150 path_node, NULL, &xendev->otherend,
151 NULL);
152 if (err) {
153 xenbus_dev_fatal(xendev, err,
154 "reading other end details from %s",
155 xendev->nodename);
156 return err;
157 }
158 if (strlen(xendev->otherend) == 0 ||
159 !xenbus_exists(XBT_NIL, xendev->otherend, "")) {
160 xenbus_dev_fatal(xendev, -ENOENT,
161 "unable to read other end from %s. "
162 "missing or inaccessible.",
163 xendev->nodename);
164 free_otherend_details(xendev);
165 return -ENOENT;
166 }
167
168 return 0;
169}
170EXPORT_SYMBOL_GPL(xenbus_read_otherend_details);
171
172void xenbus_otherend_changed(struct xenbus_watch *watch,
173 const char *path, const char *token,
174 int ignore_on_shutdown)
175{
176 struct xenbus_device *dev =
177 container_of(watch, struct xenbus_device, otherend_watch);
178 struct xenbus_driver *drv = to_xenbus_driver(dev->dev.driver);
179 enum xenbus_state state;
180
181
182
183 if (!dev->otherend ||
184 strncmp(dev->otherend, path, strlen(dev->otherend))) {
185 dev_dbg(&dev->dev, "Ignoring watch at %s\n", path);
186 return;
187 }
188
189 state = xenbus_read_driver_state(dev->otherend);
190
191 dev_dbg(&dev->dev, "state is %d, (%s), %s, %s\n",
192 state, xenbus_strstate(state), dev->otherend_watch.node, path);
193
194
195
196
197
198 if (system_state > SYSTEM_RUNNING) {
199 if (ignore_on_shutdown && (state == XenbusStateClosing))
200 xenbus_frontend_closed(dev);
201 return;
202 }
203
204 if (drv->otherend_changed)
205 drv->otherend_changed(dev, state);
206}
207EXPORT_SYMBOL_GPL(xenbus_otherend_changed);
208
209int xenbus_dev_probe(struct device *_dev)
210{
211 struct xenbus_device *dev = to_xenbus_device(_dev);
212 struct xenbus_driver *drv = to_xenbus_driver(_dev->driver);
213 const struct xenbus_device_id *id;
214 int err;
215
216 DPRINTK("%s", dev->nodename);
217
218 if (!drv->probe) {
219 err = -ENODEV;
220 goto fail;
221 }
222
223 id = match_device(drv->ids, dev);
224 if (!id) {
225 err = -ENODEV;
226 goto fail;
227 }
228
229 err = talk_to_otherend(dev);
230 if (err) {
231 dev_warn(&dev->dev, "talk_to_otherend on %s failed.\n",
232 dev->nodename);
233 return err;
234 }
235
236 if (!try_module_get(drv->driver.owner)) {
237 dev_warn(&dev->dev, "failed to acquire module reference on '%s'\n",
238 drv->driver.name);
239 err = -ESRCH;
240 goto fail;
241 }
242
243 down(&dev->reclaim_sem);
244 err = drv->probe(dev, id);
245 up(&dev->reclaim_sem);
246 if (err)
247 goto fail_put;
248
249 err = watch_otherend(dev);
250 if (err) {
251 dev_warn(&dev->dev, "watch_otherend on %s failed.\n",
252 dev->nodename);
253 return err;
254 }
255
256 return 0;
257fail_put:
258 module_put(drv->driver.owner);
259fail:
260 xenbus_dev_error(dev, err, "xenbus_dev_probe on %s", dev->nodename);
261 return err;
262}
263EXPORT_SYMBOL_GPL(xenbus_dev_probe);
264
265int xenbus_dev_remove(struct device *_dev)
266{
267 struct xenbus_device *dev = to_xenbus_device(_dev);
268 struct xenbus_driver *drv = to_xenbus_driver(_dev->driver);
269
270 DPRINTK("%s", dev->nodename);
271
272 free_otherend_watch(dev);
273
274 if (drv->remove) {
275 down(&dev->reclaim_sem);
276 drv->remove(dev);
277 up(&dev->reclaim_sem);
278 }
279
280 module_put(drv->driver.owner);
281
282 free_otherend_details(dev);
283
284
285
286
287
288
289
290 if (!drv->allow_rebind ||
291 xenbus_read_driver_state(dev->nodename) == XenbusStateClosing)
292 xenbus_switch_state(dev, XenbusStateClosed);
293
294 return 0;
295}
296EXPORT_SYMBOL_GPL(xenbus_dev_remove);
297
298int xenbus_register_driver_common(struct xenbus_driver *drv,
299 struct xen_bus_type *bus,
300 struct module *owner, const char *mod_name)
301{
302 drv->driver.name = drv->name ? drv->name : drv->ids[0].devicetype;
303 drv->driver.bus = &bus->bus;
304 drv->driver.owner = owner;
305 drv->driver.mod_name = mod_name;
306
307 return driver_register(&drv->driver);
308}
309EXPORT_SYMBOL_GPL(xenbus_register_driver_common);
310
311void xenbus_unregister_driver(struct xenbus_driver *drv)
312{
313 driver_unregister(&drv->driver);
314}
315EXPORT_SYMBOL_GPL(xenbus_unregister_driver);
316
317struct xb_find_info {
318 struct xenbus_device *dev;
319 const char *nodename;
320};
321
322static int cmp_dev(struct device *dev, void *data)
323{
324 struct xenbus_device *xendev = to_xenbus_device(dev);
325 struct xb_find_info *info = data;
326
327 if (!strcmp(xendev->nodename, info->nodename)) {
328 info->dev = xendev;
329 get_device(dev);
330 return 1;
331 }
332 return 0;
333}
334
335static struct xenbus_device *xenbus_device_find(const char *nodename,
336 struct bus_type *bus)
337{
338 struct xb_find_info info = { .dev = NULL, .nodename = nodename };
339
340 bus_for_each_dev(bus, NULL, &info, cmp_dev);
341 return info.dev;
342}
343
344static int cleanup_dev(struct device *dev, void *data)
345{
346 struct xenbus_device *xendev = to_xenbus_device(dev);
347 struct xb_find_info *info = data;
348 int len = strlen(info->nodename);
349
350 DPRINTK("%s", info->nodename);
351
352
353 if (strncmp(xendev->nodename, info->nodename, len))
354 return 0;
355
356
357 if ((strlen(xendev->nodename) > len) && (xendev->nodename[len] != '/'))
358 return 0;
359
360 info->dev = xendev;
361 get_device(dev);
362 return 1;
363}
364
365static void xenbus_cleanup_devices(const char *path, struct bus_type *bus)
366{
367 struct xb_find_info info = { .nodename = path };
368
369 do {
370 info.dev = NULL;
371 bus_for_each_dev(bus, NULL, &info, cleanup_dev);
372 if (info.dev) {
373 device_unregister(&info.dev->dev);
374 put_device(&info.dev->dev);
375 }
376 } while (info.dev);
377}
378
379static void xenbus_dev_release(struct device *dev)
380{
381 if (dev)
382 kfree(to_xenbus_device(dev));
383}
384
385static ssize_t nodename_show(struct device *dev,
386 struct device_attribute *attr, char *buf)
387{
388 return sprintf(buf, "%s\n", to_xenbus_device(dev)->nodename);
389}
390static DEVICE_ATTR_RO(nodename);
391
392static ssize_t devtype_show(struct device *dev,
393 struct device_attribute *attr, char *buf)
394{
395 return sprintf(buf, "%s\n", to_xenbus_device(dev)->devicetype);
396}
397static DEVICE_ATTR_RO(devtype);
398
399static ssize_t modalias_show(struct device *dev,
400 struct device_attribute *attr, char *buf)
401{
402 return sprintf(buf, "%s:%s\n", dev->bus->name,
403 to_xenbus_device(dev)->devicetype);
404}
405static DEVICE_ATTR_RO(modalias);
406
407static ssize_t state_show(struct device *dev,
408 struct device_attribute *attr, char *buf)
409{
410 return sprintf(buf, "%s\n",
411 xenbus_strstate(to_xenbus_device(dev)->state));
412}
413static DEVICE_ATTR_RO(state);
414
415static struct attribute *xenbus_dev_attrs[] = {
416 &dev_attr_nodename.attr,
417 &dev_attr_devtype.attr,
418 &dev_attr_modalias.attr,
419 &dev_attr_state.attr,
420 NULL,
421};
422
423static const struct attribute_group xenbus_dev_group = {
424 .attrs = xenbus_dev_attrs,
425};
426
427const struct attribute_group *xenbus_dev_groups[] = {
428 &xenbus_dev_group,
429 NULL,
430};
431EXPORT_SYMBOL_GPL(xenbus_dev_groups);
432
433int xenbus_probe_node(struct xen_bus_type *bus,
434 const char *type,
435 const char *nodename)
436{
437 char devname[XEN_BUS_ID_SIZE];
438 int err;
439 struct xenbus_device *xendev;
440 size_t stringlen;
441 char *tmpstring;
442
443 enum xenbus_state state = xenbus_read_driver_state(nodename);
444
445 if (state != XenbusStateInitialising) {
446
447
448 return 0;
449 }
450
451 stringlen = strlen(nodename) + 1 + strlen(type) + 1;
452 xendev = kzalloc(sizeof(*xendev) + stringlen, GFP_KERNEL);
453 if (!xendev)
454 return -ENOMEM;
455
456 xendev->state = XenbusStateInitialising;
457
458
459
460 tmpstring = (char *)(xendev + 1);
461 strcpy(tmpstring, nodename);
462 xendev->nodename = tmpstring;
463
464 tmpstring += strlen(tmpstring) + 1;
465 strcpy(tmpstring, type);
466 xendev->devicetype = tmpstring;
467 init_completion(&xendev->down);
468
469 xendev->dev.bus = &bus->bus;
470 xendev->dev.release = xenbus_dev_release;
471
472 err = bus->get_bus_id(devname, xendev->nodename);
473 if (err)
474 goto fail;
475
476 dev_set_name(&xendev->dev, "%s", devname);
477 sema_init(&xendev->reclaim_sem, 1);
478
479
480 err = device_register(&xendev->dev);
481 if (err) {
482 put_device(&xendev->dev);
483 xendev = NULL;
484 goto fail;
485 }
486
487 return 0;
488fail:
489 kfree(xendev);
490 return err;
491}
492EXPORT_SYMBOL_GPL(xenbus_probe_node);
493
494static int xenbus_probe_device_type(struct xen_bus_type *bus, const char *type)
495{
496 int err = 0;
497 char **dir;
498 unsigned int dir_n = 0;
499 int i;
500
501 dir = xenbus_directory(XBT_NIL, bus->root, type, &dir_n);
502 if (IS_ERR(dir))
503 return PTR_ERR(dir);
504
505 for (i = 0; i < dir_n; i++) {
506 err = bus->probe(bus, type, dir[i]);
507 if (err)
508 break;
509 }
510
511 kfree(dir);
512 return err;
513}
514
515int xenbus_probe_devices(struct xen_bus_type *bus)
516{
517 int err = 0;
518 char **dir;
519 unsigned int i, dir_n;
520
521 dir = xenbus_directory(XBT_NIL, bus->root, "", &dir_n);
522 if (IS_ERR(dir))
523 return PTR_ERR(dir);
524
525 for (i = 0; i < dir_n; i++) {
526 err = xenbus_probe_device_type(bus, dir[i]);
527 if (err)
528 break;
529 }
530
531 kfree(dir);
532 return err;
533}
534EXPORT_SYMBOL_GPL(xenbus_probe_devices);
535
536static unsigned int char_count(const char *str, char c)
537{
538 unsigned int i, ret = 0;
539
540 for (i = 0; str[i]; i++)
541 if (str[i] == c)
542 ret++;
543 return ret;
544}
545
546static int strsep_len(const char *str, char c, unsigned int len)
547{
548 unsigned int i;
549
550 for (i = 0; str[i]; i++)
551 if (str[i] == c) {
552 if (len == 0)
553 return i;
554 len--;
555 }
556 return (len == 0) ? i : -ERANGE;
557}
558
559void xenbus_dev_changed(const char *node, struct xen_bus_type *bus)
560{
561 int exists, rootlen;
562 struct xenbus_device *dev;
563 char type[XEN_BUS_ID_SIZE];
564 const char *p, *root;
565
566 if (char_count(node, '/') < 2)
567 return;
568
569 exists = xenbus_exists(XBT_NIL, node, "");
570 if (!exists) {
571 xenbus_cleanup_devices(node, &bus->bus);
572 return;
573 }
574
575
576 p = strchr(node, '/') + 1;
577 snprintf(type, XEN_BUS_ID_SIZE, "%.*s", (int)strcspn(p, "/"), p);
578 type[XEN_BUS_ID_SIZE-1] = '\0';
579
580 rootlen = strsep_len(node, '/', bus->levels);
581 if (rootlen < 0)
582 return;
583 root = kasprintf(GFP_KERNEL, "%.*s", rootlen, node);
584 if (!root)
585 return;
586
587 dev = xenbus_device_find(root, &bus->bus);
588 if (!dev)
589 xenbus_probe_node(bus, type, root);
590 else
591 put_device(&dev->dev);
592
593 kfree(root);
594}
595EXPORT_SYMBOL_GPL(xenbus_dev_changed);
596
597int xenbus_dev_suspend(struct device *dev)
598{
599 int err = 0;
600 struct xenbus_driver *drv;
601 struct xenbus_device *xdev
602 = container_of(dev, struct xenbus_device, dev);
603
604 DPRINTK("%s", xdev->nodename);
605
606 if (dev->driver == NULL)
607 return 0;
608 drv = to_xenbus_driver(dev->driver);
609 if (drv->suspend)
610 err = drv->suspend(xdev);
611 if (err)
612 dev_warn(dev, "suspend failed: %i\n", err);
613 return 0;
614}
615EXPORT_SYMBOL_GPL(xenbus_dev_suspend);
616
617int xenbus_dev_resume(struct device *dev)
618{
619 int err;
620 struct xenbus_driver *drv;
621 struct xenbus_device *xdev
622 = container_of(dev, struct xenbus_device, dev);
623
624 DPRINTK("%s", xdev->nodename);
625
626 if (dev->driver == NULL)
627 return 0;
628 drv = to_xenbus_driver(dev->driver);
629 err = talk_to_otherend(xdev);
630 if (err) {
631 dev_warn(dev, "resume (talk_to_otherend) failed: %i\n", err);
632 return err;
633 }
634
635 xdev->state = XenbusStateInitialising;
636
637 if (drv->resume) {
638 err = drv->resume(xdev);
639 if (err) {
640 dev_warn(dev, "resume failed: %i\n", err);
641 return err;
642 }
643 }
644
645 err = watch_otherend(xdev);
646 if (err) {
647 dev_warn(dev, "resume (watch_otherend) failed: %d\n", err);
648 return err;
649 }
650
651 return 0;
652}
653EXPORT_SYMBOL_GPL(xenbus_dev_resume);
654
655int xenbus_dev_cancel(struct device *dev)
656{
657
658 DPRINTK("cancel");
659 return 0;
660}
661EXPORT_SYMBOL_GPL(xenbus_dev_cancel);
662
663
664int xenstored_ready;
665
666
667int register_xenstore_notifier(struct notifier_block *nb)
668{
669 int ret = 0;
670
671 if (xenstored_ready > 0)
672 ret = nb->notifier_call(nb, 0, NULL);
673 else
674 blocking_notifier_chain_register(&xenstore_chain, nb);
675
676 return ret;
677}
678EXPORT_SYMBOL_GPL(register_xenstore_notifier);
679
680void unregister_xenstore_notifier(struct notifier_block *nb)
681{
682 blocking_notifier_chain_unregister(&xenstore_chain, nb);
683}
684EXPORT_SYMBOL_GPL(unregister_xenstore_notifier);
685
686static void xenbus_probe(void)
687{
688 xenstored_ready = 1;
689
690
691
692
693
694
695 if (xen_store_domain_type == XS_HVM)
696 xs_init();
697
698
699 blocking_notifier_call_chain(&xenstore_chain, 0, NULL);
700}
701
702
703
704
705
706
707static bool xs_hvm_defer_init_for_callback(void)
708{
709#ifdef CONFIG_XEN_PVHVM
710 return xen_store_domain_type == XS_HVM &&
711 !xen_have_vector_callback;
712#else
713 return false;
714#endif
715}
716
717static int xenbus_probe_thread(void *unused)
718{
719 DEFINE_WAIT(w);
720
721
722
723
724
725 prepare_to_wait(&xb_waitq, &w, TASK_INTERRUPTIBLE);
726 schedule();
727 finish_wait(&xb_waitq, &w);
728
729 DPRINTK("probing");
730 xenbus_probe();
731 return 0;
732}
733
734static int __init xenbus_probe_initcall(void)
735{
736
737
738
739
740 if (xen_store_domain_type == XS_PV ||
741 (xen_store_domain_type == XS_HVM &&
742 !xs_hvm_defer_init_for_callback()))
743 xenbus_probe();
744
745
746
747
748
749
750
751 if (xen_store_domain_type == XS_LOCAL) {
752 struct task_struct *probe_task;
753
754 probe_task = kthread_run(xenbus_probe_thread, NULL,
755 "xenbus_probe");
756 if (IS_ERR(probe_task))
757 return PTR_ERR(probe_task);
758 }
759 return 0;
760}
761device_initcall(xenbus_probe_initcall);
762
763int xen_set_callback_via(uint64_t via)
764{
765 struct xen_hvm_param a;
766 int ret;
767
768 a.domid = DOMID_SELF;
769 a.index = HVM_PARAM_CALLBACK_IRQ;
770 a.value = via;
771
772 ret = HYPERVISOR_hvm_op(HVMOP_set_param, &a);
773 if (ret)
774 return ret;
775
776
777
778
779
780 if (!xenstored_ready && xs_hvm_defer_init_for_callback())
781 xenbus_probe();
782
783 return ret;
784}
785EXPORT_SYMBOL_GPL(xen_set_callback_via);
786
787
788
789
790static int __init xenstored_local_init(void)
791{
792 int err = -ENOMEM;
793 unsigned long page = 0;
794 struct evtchn_alloc_unbound alloc_unbound;
795
796
797 page = get_zeroed_page(GFP_KERNEL);
798 if (!page)
799 goto out_err;
800
801 xen_store_gfn = virt_to_gfn((void *)page);
802
803
804 alloc_unbound.dom = DOMID_SELF;
805 alloc_unbound.remote_dom = DOMID_SELF;
806
807 err = HYPERVISOR_event_channel_op(EVTCHNOP_alloc_unbound,
808 &alloc_unbound);
809 if (err == -ENOSYS)
810 goto out_err;
811
812 BUG_ON(err);
813 xen_store_evtchn = alloc_unbound.port;
814
815 return 0;
816
817 out_err:
818 if (page != 0)
819 free_page(page);
820 return err;
821}
822
823static int xenbus_resume_cb(struct notifier_block *nb,
824 unsigned long action, void *data)
825{
826 int err = 0;
827
828 if (xen_hvm_domain()) {
829 uint64_t v = 0;
830
831 err = hvm_get_parameter(HVM_PARAM_STORE_EVTCHN, &v);
832 if (!err && v)
833 xen_store_evtchn = v;
834 else
835 pr_warn("Cannot update xenstore event channel: %d\n",
836 err);
837 } else
838 xen_store_evtchn = xen_start_info->store_evtchn;
839
840 return err;
841}
842
843static struct notifier_block xenbus_resume_nb = {
844 .notifier_call = xenbus_resume_cb,
845};
846
847static int __init xenbus_init(void)
848{
849 int err = 0;
850 uint64_t v = 0;
851 xen_store_domain_type = XS_UNKNOWN;
852
853 if (!xen_domain())
854 return -ENODEV;
855
856 xenbus_ring_ops_init();
857
858 if (xen_pv_domain())
859 xen_store_domain_type = XS_PV;
860 if (xen_hvm_domain())
861 xen_store_domain_type = XS_HVM;
862 if (xen_hvm_domain() && xen_initial_domain())
863 xen_store_domain_type = XS_LOCAL;
864 if (xen_pv_domain() && !xen_start_info->store_evtchn)
865 xen_store_domain_type = XS_LOCAL;
866 if (xen_pv_domain() && xen_start_info->store_evtchn)
867 xenstored_ready = 1;
868
869 switch (xen_store_domain_type) {
870 case XS_LOCAL:
871 err = xenstored_local_init();
872 if (err)
873 goto out_error;
874 xen_store_interface = gfn_to_virt(xen_store_gfn);
875 break;
876 case XS_PV:
877 xen_store_evtchn = xen_start_info->store_evtchn;
878 xen_store_gfn = xen_start_info->store_mfn;
879 xen_store_interface = gfn_to_virt(xen_store_gfn);
880 break;
881 case XS_HVM:
882 err = hvm_get_parameter(HVM_PARAM_STORE_EVTCHN, &v);
883 if (err)
884 goto out_error;
885 xen_store_evtchn = (int)v;
886 err = hvm_get_parameter(HVM_PARAM_STORE_PFN, &v);
887 if (err)
888 goto out_error;
889 xen_store_gfn = (unsigned long)v;
890 xen_store_interface =
891 xen_remap(xen_store_gfn << XEN_PAGE_SHIFT,
892 XEN_PAGE_SIZE);
893 break;
894 default:
895 pr_warn("Xenstore state unknown\n");
896 break;
897 }
898
899
900
901
902
903
904 if (xen_store_domain_type != XS_HVM) {
905 err = xs_init();
906 if (err) {
907 pr_warn("Error initializing xenstore comms: %i\n", err);
908 goto out_error;
909 }
910 }
911
912 if ((xen_store_domain_type != XS_LOCAL) &&
913 (xen_store_domain_type != XS_UNKNOWN))
914 xen_resume_notifier_register(&xenbus_resume_nb);
915
916#ifdef CONFIG_XEN_COMPAT_XENFS
917
918
919
920
921 proc_create_mount_point("xen");
922#endif
923
924out_error:
925 return err;
926}
927
928postcore_initcall(xenbus_init);
929
930MODULE_LICENSE("GPL");
931