1 /******************************************************************************
2 * Talks to Xen Store to figure out what devices we have.
4 * Copyright (C) 2005 Rusty Russell, IBM Corporation
5 * Copyright (C) 2005 Mike Wray, Hewlett-Packard
6 * Copyright (C) 2005, 2006 XenSource Ltd
8 * This program is free software; you can redistribute it and/or
9 * modify it under the terms of the GNU General Public License version 2
10 * as published by the Free Software Foundation; or, when distributed
11 * separately from the Linux kernel or incorporated into other
12 * software packages, subject to the following license:
14 * Permission is hereby granted, free of charge, to any person obtaining a copy
15 * of this source file (the "Software"), to deal in the Software without
16 * restriction, including without limitation the rights to use, copy, modify,
17 * merge, publish, distribute, sublicense, and/or sell copies of the Software,
18 * and to permit persons to whom the Software is furnished to do so, subject to
19 * the following conditions:
21 * The above copyright notice and this permission notice shall be included in
22 * all copies or substantial portions of the Software.
24 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
25 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
26 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
27 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
28 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
29 * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
33 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
34 #define dev_fmt pr_fmt
36 #define DPRINTK(fmt, args...) \
37 pr_debug("xenbus_probe (%s:%d) " fmt ".\n", \
38 __func__, __LINE__, ##args)
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>
46 #include <linux/proc_fs.h>
47 #include <linux/notifier.h>
48 #include <linux/kthread.h>
49 #include <linux/mutex.h>
51 #include <linux/slab.h>
52 #include <linux/module.h>
55 #include <asm/xen/hypervisor.h>
58 #include <xen/xenbus.h>
59 #include <xen/events.h>
60 #include <xen/xen-ops.h>
69 EXPORT_SYMBOL_GPL(xen_store_evtchn);
71 struct xenstore_domain_interface *xen_store_interface;
72 EXPORT_SYMBOL_GPL(xen_store_interface);
74 enum xenstore_init xen_store_domain_type;
75 EXPORT_SYMBOL_GPL(xen_store_domain_type);
77 static unsigned long xen_store_gfn;
79 static BLOCKING_NOTIFIER_HEAD(xenstore_chain);
81 /* If something in array of ids matches this device, return it. */
82 static const struct xenbus_device_id *
83 match_device(const struct xenbus_device_id *arr, struct xenbus_device *dev)
85 for (; *arr->devicetype != '\0'; arr++) {
86 if (!strcmp(arr->devicetype, dev->devicetype))
92 int xenbus_match(struct device *_dev, struct device_driver *_drv)
94 struct xenbus_driver *drv = to_xenbus_driver(_drv);
99 return match_device(drv->ids, to_xenbus_device(_dev)) != NULL;
101 EXPORT_SYMBOL_GPL(xenbus_match);
104 static void free_otherend_details(struct xenbus_device *dev)
106 kfree(dev->otherend);
107 dev->otherend = NULL;
111 static void free_otherend_watch(struct xenbus_device *dev)
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;
121 static int talk_to_otherend(struct xenbus_device *dev)
123 struct xenbus_driver *drv = to_xenbus_driver(dev->dev.driver);
125 free_otherend_watch(dev);
126 free_otherend_details(dev);
128 return drv->read_otherend_details(dev);
133 static int watch_otherend(struct xenbus_device *dev)
135 struct xen_bus_type *bus =
136 container_of(dev->dev.bus, struct xen_bus_type, bus);
138 return xenbus_watch_pathfmt(dev, &dev->otherend_watch,
139 bus->otherend_will_handle,
140 bus->otherend_changed,
141 "%s/%s", dev->otherend, "state");
145 int xenbus_read_otherend_details(struct xenbus_device *xendev,
146 char *id_node, char *path_node)
148 int err = xenbus_gather(XBT_NIL, xendev->nodename,
149 id_node, "%i", &xendev->otherend_id,
150 path_node, NULL, &xendev->otherend,
153 xenbus_dev_fatal(xendev, err,
154 "reading other end details from %s",
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.",
164 free_otherend_details(xendev);
170 EXPORT_SYMBOL_GPL(xenbus_read_otherend_details);
172 void xenbus_otherend_changed(struct xenbus_watch *watch,
173 const char *path, const char *token,
174 int ignore_on_shutdown)
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;
181 /* Protect us against watches firing on old details when the otherend
182 details change, say immediately after a resume. */
183 if (!dev->otherend ||
184 strncmp(dev->otherend, path, strlen(dev->otherend))) {
185 dev_dbg(&dev->dev, "Ignoring watch at %s\n", path);
189 state = xenbus_read_driver_state(dev->otherend);
191 dev_dbg(&dev->dev, "state is %d, (%s), %s, %s\n",
192 state, xenbus_strstate(state), dev->otherend_watch.node, path);
195 * Ignore xenbus transitions during shutdown. This prevents us doing
196 * work that can fail e.g., when the rootfs is gone.
198 if (system_state > SYSTEM_RUNNING) {
199 if (ignore_on_shutdown && (state == XenbusStateClosing))
200 xenbus_frontend_closed(dev);
204 if (drv->otherend_changed)
205 drv->otherend_changed(dev, state);
207 EXPORT_SYMBOL_GPL(xenbus_otherend_changed);
209 #define XENBUS_SHOW_STAT(name) \
210 static ssize_t name##_show(struct device *_dev, \
211 struct device_attribute *attr, \
214 struct xenbus_device *dev = to_xenbus_device(_dev); \
216 return sprintf(buf, "%d\n", atomic_read(&dev->name)); \
218 static DEVICE_ATTR_RO(name)
220 XENBUS_SHOW_STAT(event_channels);
221 XENBUS_SHOW_STAT(events);
222 XENBUS_SHOW_STAT(spurious_events);
223 XENBUS_SHOW_STAT(jiffies_eoi_delayed);
225 static ssize_t spurious_threshold_show(struct device *_dev,
226 struct device_attribute *attr,
229 struct xenbus_device *dev = to_xenbus_device(_dev);
231 return sprintf(buf, "%d\n", dev->spurious_threshold);
234 static ssize_t spurious_threshold_store(struct device *_dev,
235 struct device_attribute *attr,
236 const char *buf, size_t count)
238 struct xenbus_device *dev = to_xenbus_device(_dev);
242 ret = kstrtouint(buf, 0, &val);
246 dev->spurious_threshold = val;
251 static DEVICE_ATTR_RW(spurious_threshold);
253 static struct attribute *xenbus_attrs[] = {
254 &dev_attr_event_channels.attr,
255 &dev_attr_events.attr,
256 &dev_attr_spurious_events.attr,
257 &dev_attr_jiffies_eoi_delayed.attr,
258 &dev_attr_spurious_threshold.attr,
262 static const struct attribute_group xenbus_group = {
264 .attrs = xenbus_attrs,
267 int xenbus_dev_probe(struct device *_dev)
269 struct xenbus_device *dev = to_xenbus_device(_dev);
270 struct xenbus_driver *drv = to_xenbus_driver(_dev->driver);
271 const struct xenbus_device_id *id;
274 DPRINTK("%s", dev->nodename);
281 id = match_device(drv->ids, dev);
287 err = talk_to_otherend(dev);
289 dev_warn(&dev->dev, "talk_to_otherend on %s failed.\n",
294 if (!try_module_get(drv->driver.owner)) {
295 dev_warn(&dev->dev, "failed to acquire module reference on '%s'\n",
301 down(&dev->reclaim_sem);
302 err = drv->probe(dev, id);
303 up(&dev->reclaim_sem);
307 err = watch_otherend(dev);
309 dev_warn(&dev->dev, "watch_otherend on %s failed.\n",
314 dev->spurious_threshold = 1;
315 if (sysfs_create_group(&dev->dev.kobj, &xenbus_group))
316 dev_warn(&dev->dev, "sysfs_create_group on %s failed.\n",
321 module_put(drv->driver.owner);
323 xenbus_dev_error(dev, err, "xenbus_dev_probe on %s", dev->nodename);
326 EXPORT_SYMBOL_GPL(xenbus_dev_probe);
328 void xenbus_dev_remove(struct device *_dev)
330 struct xenbus_device *dev = to_xenbus_device(_dev);
331 struct xenbus_driver *drv = to_xenbus_driver(_dev->driver);
333 DPRINTK("%s", dev->nodename);
335 sysfs_remove_group(&dev->dev.kobj, &xenbus_group);
337 free_otherend_watch(dev);
340 down(&dev->reclaim_sem);
342 up(&dev->reclaim_sem);
345 module_put(drv->driver.owner);
347 free_otherend_details(dev);
350 * If the toolstack has forced the device state to closing then set
351 * the state to closed now to allow it to be cleaned up.
352 * Similarly, if the driver does not support re-bind, set the
355 if (!drv->allow_rebind ||
356 xenbus_read_driver_state(dev->nodename) == XenbusStateClosing)
357 xenbus_switch_state(dev, XenbusStateClosed);
359 EXPORT_SYMBOL_GPL(xenbus_dev_remove);
361 int xenbus_register_driver_common(struct xenbus_driver *drv,
362 struct xen_bus_type *bus,
363 struct module *owner, const char *mod_name)
365 drv->driver.name = drv->name ? drv->name : drv->ids[0].devicetype;
366 drv->driver.bus = &bus->bus;
367 drv->driver.owner = owner;
368 drv->driver.mod_name = mod_name;
370 return driver_register(&drv->driver);
372 EXPORT_SYMBOL_GPL(xenbus_register_driver_common);
374 void xenbus_unregister_driver(struct xenbus_driver *drv)
376 driver_unregister(&drv->driver);
378 EXPORT_SYMBOL_GPL(xenbus_unregister_driver);
380 struct xb_find_info {
381 struct xenbus_device *dev;
382 const char *nodename;
385 static int cmp_dev(struct device *dev, void *data)
387 struct xenbus_device *xendev = to_xenbus_device(dev);
388 struct xb_find_info *info = data;
390 if (!strcmp(xendev->nodename, info->nodename)) {
398 static struct xenbus_device *xenbus_device_find(const char *nodename,
399 struct bus_type *bus)
401 struct xb_find_info info = { .dev = NULL, .nodename = nodename };
403 bus_for_each_dev(bus, NULL, &info, cmp_dev);
407 static int cleanup_dev(struct device *dev, void *data)
409 struct xenbus_device *xendev = to_xenbus_device(dev);
410 struct xb_find_info *info = data;
411 int len = strlen(info->nodename);
413 DPRINTK("%s", info->nodename);
415 /* Match the info->nodename path, or any subdirectory of that path. */
416 if (strncmp(xendev->nodename, info->nodename, len))
419 /* If the node name is longer, ensure it really is a subdirectory. */
420 if ((strlen(xendev->nodename) > len) && (xendev->nodename[len] != '/'))
428 static void xenbus_cleanup_devices(const char *path, struct bus_type *bus)
430 struct xb_find_info info = { .nodename = path };
434 bus_for_each_dev(bus, NULL, &info, cleanup_dev);
436 device_unregister(&info.dev->dev);
437 put_device(&info.dev->dev);
442 static void xenbus_dev_release(struct device *dev)
445 kfree(to_xenbus_device(dev));
448 static ssize_t nodename_show(struct device *dev,
449 struct device_attribute *attr, char *buf)
451 return sprintf(buf, "%s\n", to_xenbus_device(dev)->nodename);
453 static DEVICE_ATTR_RO(nodename);
455 static ssize_t devtype_show(struct device *dev,
456 struct device_attribute *attr, char *buf)
458 return sprintf(buf, "%s\n", to_xenbus_device(dev)->devicetype);
460 static DEVICE_ATTR_RO(devtype);
462 static ssize_t modalias_show(struct device *dev,
463 struct device_attribute *attr, char *buf)
465 return sprintf(buf, "%s:%s\n", dev->bus->name,
466 to_xenbus_device(dev)->devicetype);
468 static DEVICE_ATTR_RO(modalias);
470 static ssize_t state_show(struct device *dev,
471 struct device_attribute *attr, char *buf)
473 return sprintf(buf, "%s\n",
474 xenbus_strstate(to_xenbus_device(dev)->state));
476 static DEVICE_ATTR_RO(state);
478 static struct attribute *xenbus_dev_attrs[] = {
479 &dev_attr_nodename.attr,
480 &dev_attr_devtype.attr,
481 &dev_attr_modalias.attr,
482 &dev_attr_state.attr,
486 static const struct attribute_group xenbus_dev_group = {
487 .attrs = xenbus_dev_attrs,
490 const struct attribute_group *xenbus_dev_groups[] = {
494 EXPORT_SYMBOL_GPL(xenbus_dev_groups);
496 int xenbus_probe_node(struct xen_bus_type *bus,
498 const char *nodename)
500 char devname[XEN_BUS_ID_SIZE];
502 struct xenbus_device *xendev;
506 enum xenbus_state state = xenbus_read_driver_state(nodename);
508 if (state != XenbusStateInitialising) {
509 /* Device is not new, so ignore it. This can happen if a
510 device is going away after switching to Closed. */
514 stringlen = strlen(nodename) + 1 + strlen(type) + 1;
515 xendev = kzalloc(sizeof(*xendev) + stringlen, GFP_KERNEL);
519 xendev->state = XenbusStateInitialising;
521 /* Copy the strings into the extra space. */
523 tmpstring = (char *)(xendev + 1);
524 strcpy(tmpstring, nodename);
525 xendev->nodename = tmpstring;
527 tmpstring += strlen(tmpstring) + 1;
528 strcpy(tmpstring, type);
529 xendev->devicetype = tmpstring;
530 init_completion(&xendev->down);
532 xendev->dev.bus = &bus->bus;
533 xendev->dev.release = xenbus_dev_release;
535 err = bus->get_bus_id(devname, xendev->nodename);
539 dev_set_name(&xendev->dev, "%s", devname);
540 sema_init(&xendev->reclaim_sem, 1);
542 /* Register with generic device framework. */
543 err = device_register(&xendev->dev);
545 put_device(&xendev->dev);
555 EXPORT_SYMBOL_GPL(xenbus_probe_node);
557 static int xenbus_probe_device_type(struct xen_bus_type *bus, const char *type)
561 unsigned int dir_n = 0;
564 dir = xenbus_directory(XBT_NIL, bus->root, type, &dir_n);
568 for (i = 0; i < dir_n; i++) {
569 err = bus->probe(bus, type, dir[i]);
578 int xenbus_probe_devices(struct xen_bus_type *bus)
582 unsigned int i, dir_n;
584 dir = xenbus_directory(XBT_NIL, bus->root, "", &dir_n);
588 for (i = 0; i < dir_n; i++) {
589 err = xenbus_probe_device_type(bus, dir[i]);
597 EXPORT_SYMBOL_GPL(xenbus_probe_devices);
599 static unsigned int char_count(const char *str, char c)
601 unsigned int i, ret = 0;
603 for (i = 0; str[i]; i++)
609 static int strsep_len(const char *str, char c, unsigned int len)
613 for (i = 0; str[i]; i++)
619 return (len == 0) ? i : -ERANGE;
622 void xenbus_dev_changed(const char *node, struct xen_bus_type *bus)
625 struct xenbus_device *dev;
626 char type[XEN_BUS_ID_SIZE];
627 const char *p, *root;
629 if (char_count(node, '/') < 2)
632 exists = xenbus_exists(XBT_NIL, node, "");
634 xenbus_cleanup_devices(node, &bus->bus);
638 /* backend/<type>/... or device/<type>/... */
639 p = strchr(node, '/') + 1;
640 snprintf(type, XEN_BUS_ID_SIZE, "%.*s", (int)strcspn(p, "/"), p);
641 type[XEN_BUS_ID_SIZE-1] = '\0';
643 rootlen = strsep_len(node, '/', bus->levels);
646 root = kasprintf(GFP_KERNEL, "%.*s", rootlen, node);
650 dev = xenbus_device_find(root, &bus->bus);
652 xenbus_probe_node(bus, type, root);
654 put_device(&dev->dev);
658 EXPORT_SYMBOL_GPL(xenbus_dev_changed);
660 int xenbus_dev_suspend(struct device *dev)
663 struct xenbus_driver *drv;
664 struct xenbus_device *xdev
665 = container_of(dev, struct xenbus_device, dev);
667 DPRINTK("%s", xdev->nodename);
669 if (dev->driver == NULL)
671 drv = to_xenbus_driver(dev->driver);
673 err = drv->suspend(xdev);
675 dev_warn(dev, "suspend failed: %i\n", err);
678 EXPORT_SYMBOL_GPL(xenbus_dev_suspend);
680 int xenbus_dev_resume(struct device *dev)
683 struct xenbus_driver *drv;
684 struct xenbus_device *xdev
685 = container_of(dev, struct xenbus_device, dev);
687 DPRINTK("%s", xdev->nodename);
689 if (dev->driver == NULL)
691 drv = to_xenbus_driver(dev->driver);
692 err = talk_to_otherend(xdev);
694 dev_warn(dev, "resume (talk_to_otherend) failed: %i\n", err);
698 xdev->state = XenbusStateInitialising;
701 err = drv->resume(xdev);
703 dev_warn(dev, "resume failed: %i\n", err);
708 err = watch_otherend(xdev);
710 dev_warn(dev, "resume (watch_otherend) failed: %d\n", err);
716 EXPORT_SYMBOL_GPL(xenbus_dev_resume);
718 int xenbus_dev_cancel(struct device *dev)
724 EXPORT_SYMBOL_GPL(xenbus_dev_cancel);
726 /* A flag to determine if xenstored is 'ready' (i.e. has started) */
730 int register_xenstore_notifier(struct notifier_block *nb)
734 if (xenstored_ready > 0)
735 ret = nb->notifier_call(nb, 0, NULL);
737 blocking_notifier_chain_register(&xenstore_chain, nb);
741 EXPORT_SYMBOL_GPL(register_xenstore_notifier);
743 void unregister_xenstore_notifier(struct notifier_block *nb)
745 blocking_notifier_chain_unregister(&xenstore_chain, nb);
747 EXPORT_SYMBOL_GPL(unregister_xenstore_notifier);
749 static void xenbus_probe(void)
754 * In the HVM case, xenbus_init() deferred its call to
755 * xs_init() in case callbacks were not operational yet.
758 if (xen_store_domain_type == XS_HVM)
761 /* Notify others that xenstore is up */
762 blocking_notifier_call_chain(&xenstore_chain, 0, NULL);
766 * Returns true when XenStore init must be deferred in order to
767 * allow the PCI platform device to be initialised, before we
768 * can actually have event channel interrupts working.
770 static bool xs_hvm_defer_init_for_callback(void)
772 #ifdef CONFIG_XEN_PVHVM
773 return xen_store_domain_type == XS_HVM &&
774 !xen_have_vector_callback;
780 static int xenbus_probe_thread(void *unused)
785 * We actually just want to wait for *any* trigger of xb_waitq,
786 * and run xenbus_probe() the moment it occurs.
788 prepare_to_wait(&xb_waitq, &w, TASK_INTERRUPTIBLE);
790 finish_wait(&xb_waitq, &w);
797 static int __init xenbus_probe_initcall(void)
800 * Probe XenBus here in the XS_PV case, and also XS_HVM unless we
801 * need to wait for the platform PCI device to come up.
803 if (xen_store_domain_type == XS_PV ||
804 (xen_store_domain_type == XS_HVM &&
805 !xs_hvm_defer_init_for_callback()))
809 * For XS_LOCAL, spawn a thread which will wait for xenstored
810 * or a xenstore-stubdom to be started, then probe. It will be
811 * triggered when communication starts happening, by waiting
814 if (xen_store_domain_type == XS_LOCAL) {
815 struct task_struct *probe_task;
817 probe_task = kthread_run(xenbus_probe_thread, NULL,
819 if (IS_ERR(probe_task))
820 return PTR_ERR(probe_task);
824 device_initcall(xenbus_probe_initcall);
826 int xen_set_callback_via(uint64_t via)
828 struct xen_hvm_param a;
831 a.domid = DOMID_SELF;
832 a.index = HVM_PARAM_CALLBACK_IRQ;
835 ret = HYPERVISOR_hvm_op(HVMOP_set_param, &a);
840 * If xenbus_probe_initcall() deferred the xenbus_probe()
841 * due to the callback not functioning yet, we can do it now.
843 if (!xenstored_ready && xs_hvm_defer_init_for_callback())
848 EXPORT_SYMBOL_GPL(xen_set_callback_via);
850 /* Set up event channel for xenstored which is run as a local process
851 * (this is normally used only in dom0)
853 static int __init xenstored_local_init(void)
856 unsigned long page = 0;
857 struct evtchn_alloc_unbound alloc_unbound;
859 /* Allocate Xenstore page */
860 page = get_zeroed_page(GFP_KERNEL);
864 xen_store_gfn = virt_to_gfn((void *)page);
866 /* Next allocate a local port which xenstored can bind to */
867 alloc_unbound.dom = DOMID_SELF;
868 alloc_unbound.remote_dom = DOMID_SELF;
870 err = HYPERVISOR_event_channel_op(EVTCHNOP_alloc_unbound,
876 xen_store_evtchn = alloc_unbound.port;
886 static int xenbus_resume_cb(struct notifier_block *nb,
887 unsigned long action, void *data)
891 if (xen_hvm_domain()) {
894 err = hvm_get_parameter(HVM_PARAM_STORE_EVTCHN, &v);
896 xen_store_evtchn = v;
898 pr_warn("Cannot update xenstore event channel: %d\n",
901 xen_store_evtchn = xen_start_info->store_evtchn;
906 static struct notifier_block xenbus_resume_nb = {
907 .notifier_call = xenbus_resume_cb,
910 static int __init xenbus_init(void)
914 xen_store_domain_type = XS_UNKNOWN;
919 xenbus_ring_ops_init();
922 xen_store_domain_type = XS_PV;
923 if (xen_hvm_domain())
924 xen_store_domain_type = XS_HVM;
925 if (xen_hvm_domain() && xen_initial_domain())
926 xen_store_domain_type = XS_LOCAL;
927 if (xen_pv_domain() && !xen_start_info->store_evtchn)
928 xen_store_domain_type = XS_LOCAL;
929 if (xen_pv_domain() && xen_start_info->store_evtchn)
932 switch (xen_store_domain_type) {
934 err = xenstored_local_init();
937 xen_store_interface = gfn_to_virt(xen_store_gfn);
940 xen_store_evtchn = xen_start_info->store_evtchn;
941 xen_store_gfn = xen_start_info->store_mfn;
942 xen_store_interface = gfn_to_virt(xen_store_gfn);
945 err = hvm_get_parameter(HVM_PARAM_STORE_EVTCHN, &v);
948 xen_store_evtchn = (int)v;
949 err = hvm_get_parameter(HVM_PARAM_STORE_PFN, &v);
953 * Uninitialized hvm_params are zero and return no error.
954 * Although it is theoretically possible to have
955 * HVM_PARAM_STORE_PFN set to zero on purpose, in reality it is
956 * not zero when valid. If zero, it means that Xenstore hasn't
957 * been properly initialized. Instead of attempting to map a
958 * wrong guest physical address return error.
960 * Also recognize all bits set as an invalid value.
966 /* Avoid truncation on 32-bit. */
967 #if BITS_PER_LONG == 32
969 pr_err("%s: cannot handle HVM_PARAM_STORE_PFN=%llx > ULONG_MAX\n",
975 xen_store_gfn = (unsigned long)v;
976 xen_store_interface =
977 xen_remap(xen_store_gfn << XEN_PAGE_SHIFT,
981 pr_warn("Xenstore state unknown\n");
986 * HVM domains may not have a functional callback yet. In that
987 * case let xs_init() be called from xenbus_probe(), which will
988 * get invoked at an appropriate time.
990 if (xen_store_domain_type != XS_HVM) {
993 pr_warn("Error initializing xenstore comms: %i\n", err);
998 if ((xen_store_domain_type != XS_LOCAL) &&
999 (xen_store_domain_type != XS_UNKNOWN))
1000 xen_resume_notifier_register(&xenbus_resume_nb);
1002 #ifdef CONFIG_XEN_COMPAT_XENFS
1004 * Create xenfs mountpoint in /proc for compatibility with
1005 * utilities that expect to find "xenbus" under "/proc/xen".
1007 proc_create_mount_point("xen");
1012 xen_store_domain_type = XS_UNKNOWN;
1016 postcore_initcall(xenbus_init);
1018 MODULE_LICENSE("GPL");