Commit | Line | Data |
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4bac07c9 JF |
1 | /****************************************************************************** |
2 | * Talks to Xen Store to figure out what devices we have. | |
3 | * | |
4 | * Copyright (C) 2005 Rusty Russell, IBM Corporation | |
5 | * Copyright (C) 2005 Mike Wray, Hewlett-Packard | |
6 | * Copyright (C) 2005, 2006 XenSource Ltd | |
7 | * | |
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: | |
13 | * | |
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: | |
20 | * | |
21 | * The above copyright notice and this permission notice shall be included in | |
22 | * all copies or substantial portions of the Software. | |
23 | * | |
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 | |
30 | * IN THE SOFTWARE. | |
31 | */ | |
32 | ||
283c0972 JP |
33 | #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt |
34 | ||
4bac07c9 JF |
35 | #define DPRINTK(fmt, args...) \ |
36 | pr_debug("xenbus_probe (%s:%d) " fmt ".\n", \ | |
37 | __func__, __LINE__, ##args) | |
38 | ||
39 | #include <linux/kernel.h> | |
40 | #include <linux/err.h> | |
41 | #include <linux/string.h> | |
42 | #include <linux/ctype.h> | |
43 | #include <linux/fcntl.h> | |
44 | #include <linux/mm.h> | |
1107ba88 | 45 | #include <linux/proc_fs.h> |
4bac07c9 JF |
46 | #include <linux/notifier.h> |
47 | #include <linux/kthread.h> | |
48 | #include <linux/mutex.h> | |
49 | #include <linux/io.h> | |
5a0e3ad6 | 50 | #include <linux/slab.h> |
72ee5112 | 51 | #include <linux/module.h> |
4bac07c9 JF |
52 | |
53 | #include <asm/page.h> | |
54 | #include <asm/pgtable.h> | |
55 | #include <asm/xen/hypervisor.h> | |
1ccbf534 JF |
56 | |
57 | #include <xen/xen.h> | |
4bac07c9 JF |
58 | #include <xen/xenbus.h> |
59 | #include <xen/events.h> | |
16f1cf3b | 60 | #include <xen/xen-ops.h> |
4bac07c9 JF |
61 | #include <xen/page.h> |
62 | ||
bee6ab53 SY |
63 | #include <xen/hvm.h> |
64 | ||
4bac07c9 JF |
65 | #include "xenbus_comms.h" |
66 | #include "xenbus_probe.h" | |
67 | ||
1107ba88 | 68 | |
4bac07c9 | 69 | int xen_store_evtchn; |
8e3e9991 | 70 | EXPORT_SYMBOL_GPL(xen_store_evtchn); |
1107ba88 | 71 | |
4bac07c9 | 72 | struct xenstore_domain_interface *xen_store_interface; |
8e3e9991 JF |
73 | EXPORT_SYMBOL_GPL(xen_store_interface); |
74 | ||
33c1174b AC |
75 | enum xenstore_init xen_store_domain_type; |
76 | EXPORT_SYMBOL_GPL(xen_store_domain_type); | |
77 | ||
5f51042f | 78 | static unsigned long xen_store_gfn; |
4bac07c9 JF |
79 | |
80 | static BLOCKING_NOTIFIER_HEAD(xenstore_chain); | |
81 | ||
4bac07c9 JF |
82 | /* If something in array of ids matches this device, return it. */ |
83 | static const struct xenbus_device_id * | |
84 | match_device(const struct xenbus_device_id *arr, struct xenbus_device *dev) | |
85 | { | |
86 | for (; *arr->devicetype != '\0'; arr++) { | |
87 | if (!strcmp(arr->devicetype, dev->devicetype)) | |
88 | return arr; | |
89 | } | |
90 | return NULL; | |
91 | } | |
92 | ||
93 | int xenbus_match(struct device *_dev, struct device_driver *_drv) | |
94 | { | |
95 | struct xenbus_driver *drv = to_xenbus_driver(_drv); | |
96 | ||
97 | if (!drv->ids) | |
98 | return 0; | |
99 | ||
100 | return match_device(drv->ids, to_xenbus_device(_dev)) != NULL; | |
101 | } | |
2de06cc1 IC |
102 | EXPORT_SYMBOL_GPL(xenbus_match); |
103 | ||
4bac07c9 | 104 | |
4bac07c9 JF |
105 | static void free_otherend_details(struct xenbus_device *dev) |
106 | { | |
107 | kfree(dev->otherend); | |
108 | dev->otherend = NULL; | |
109 | } | |
110 | ||
111 | ||
112 | static void free_otherend_watch(struct xenbus_device *dev) | |
113 | { | |
114 | if (dev->otherend_watch.node) { | |
115 | unregister_xenbus_watch(&dev->otherend_watch); | |
116 | kfree(dev->otherend_watch.node); | |
117 | dev->otherend_watch.node = NULL; | |
118 | } | |
119 | } | |
120 | ||
121 | ||
2de06cc1 IC |
122 | static int talk_to_otherend(struct xenbus_device *dev) |
123 | { | |
124 | struct xenbus_driver *drv = to_xenbus_driver(dev->dev.driver); | |
125 | ||
126 | free_otherend_watch(dev); | |
127 | free_otherend_details(dev); | |
128 | ||
129 | return drv->read_otherend_details(dev); | |
130 | } | |
131 | ||
132 | ||
133 | ||
134 | static int watch_otherend(struct xenbus_device *dev) | |
135 | { | |
6bac7f9f IC |
136 | struct xen_bus_type *bus = |
137 | container_of(dev->dev.bus, struct xen_bus_type, bus); | |
2de06cc1 | 138 | |
6bac7f9f IC |
139 | return xenbus_watch_pathfmt(dev, &dev->otherend_watch, |
140 | bus->otherend_changed, | |
2de06cc1 IC |
141 | "%s/%s", dev->otherend, "state"); |
142 | } | |
143 | ||
144 | ||
145 | int xenbus_read_otherend_details(struct xenbus_device *xendev, | |
4bac07c9 JF |
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 | } | |
2de06cc1 | 170 | EXPORT_SYMBOL_GPL(xenbus_read_otherend_details); |
4bac07c9 | 171 | |
2de06cc1 IC |
172 | void xenbus_otherend_changed(struct xenbus_watch *watch, |
173 | const char **vec, unsigned int len, | |
174 | int ignore_on_shutdown) | |
4bac07c9 JF |
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 | /* 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, vec[XS_WATCH_PATH], | |
185 | strlen(dev->otherend))) { | |
898eb71c JP |
186 | dev_dbg(&dev->dev, "Ignoring watch at %s\n", |
187 | vec[XS_WATCH_PATH]); | |
4bac07c9 JF |
188 | return; |
189 | } | |
190 | ||
191 | state = xenbus_read_driver_state(dev->otherend); | |
192 | ||
898eb71c | 193 | dev_dbg(&dev->dev, "state is %d, (%s), %s, %s\n", |
4bac07c9 JF |
194 | state, xenbus_strstate(state), dev->otherend_watch.node, |
195 | vec[XS_WATCH_PATH]); | |
196 | ||
197 | /* | |
198 | * Ignore xenbus transitions during shutdown. This prevents us doing | |
199 | * work that can fail e.g., when the rootfs is gone. | |
200 | */ | |
201 | if (system_state > SYSTEM_RUNNING) { | |
2de06cc1 | 202 | if (ignore_on_shutdown && (state == XenbusStateClosing)) |
4bac07c9 JF |
203 | xenbus_frontend_closed(dev); |
204 | return; | |
205 | } | |
206 | ||
207 | if (drv->otherend_changed) | |
208 | drv->otherend_changed(dev, state); | |
209 | } | |
2de06cc1 | 210 | EXPORT_SYMBOL_GPL(xenbus_otherend_changed); |
4bac07c9 JF |
211 | |
212 | int xenbus_dev_probe(struct device *_dev) | |
213 | { | |
214 | struct xenbus_device *dev = to_xenbus_device(_dev); | |
215 | struct xenbus_driver *drv = to_xenbus_driver(_dev->driver); | |
216 | const struct xenbus_device_id *id; | |
217 | int err; | |
218 | ||
219 | DPRINTK("%s", dev->nodename); | |
220 | ||
221 | if (!drv->probe) { | |
222 | err = -ENODEV; | |
223 | goto fail; | |
224 | } | |
225 | ||
226 | id = match_device(drv->ids, dev); | |
227 | if (!id) { | |
228 | err = -ENODEV; | |
229 | goto fail; | |
230 | } | |
231 | ||
232 | err = talk_to_otherend(dev); | |
233 | if (err) { | |
234 | dev_warn(&dev->dev, "talk_to_otherend on %s failed.\n", | |
235 | dev->nodename); | |
236 | return err; | |
237 | } | |
238 | ||
239 | err = drv->probe(dev, id); | |
240 | if (err) | |
241 | goto fail; | |
242 | ||
243 | err = watch_otherend(dev); | |
244 | if (err) { | |
245 | dev_warn(&dev->dev, "watch_otherend on %s failed.\n", | |
246 | dev->nodename); | |
247 | return err; | |
248 | } | |
249 | ||
250 | return 0; | |
251 | fail: | |
252 | xenbus_dev_error(dev, err, "xenbus_dev_probe on %s", dev->nodename); | |
253 | xenbus_switch_state(dev, XenbusStateClosed); | |
7432e4bd | 254 | return err; |
4bac07c9 | 255 | } |
2de06cc1 | 256 | EXPORT_SYMBOL_GPL(xenbus_dev_probe); |
4bac07c9 JF |
257 | |
258 | int xenbus_dev_remove(struct device *_dev) | |
259 | { | |
260 | struct xenbus_device *dev = to_xenbus_device(_dev); | |
261 | struct xenbus_driver *drv = to_xenbus_driver(_dev->driver); | |
262 | ||
263 | DPRINTK("%s", dev->nodename); | |
264 | ||
265 | free_otherend_watch(dev); | |
4bac07c9 JF |
266 | |
267 | if (drv->remove) | |
268 | drv->remove(dev); | |
269 | ||
bd0d5aa4 JB |
270 | free_otherend_details(dev); |
271 | ||
4bac07c9 JF |
272 | xenbus_switch_state(dev, XenbusStateClosed); |
273 | return 0; | |
274 | } | |
2de06cc1 | 275 | EXPORT_SYMBOL_GPL(xenbus_dev_remove); |
4bac07c9 | 276 | |
2de06cc1 | 277 | void xenbus_dev_shutdown(struct device *_dev) |
4bac07c9 JF |
278 | { |
279 | struct xenbus_device *dev = to_xenbus_device(_dev); | |
280 | unsigned long timeout = 5*HZ; | |
281 | ||
282 | DPRINTK("%s", dev->nodename); | |
283 | ||
284 | get_device(&dev->dev); | |
285 | if (dev->state != XenbusStateConnected) { | |
283c0972 JP |
286 | pr_info("%s: %s: %s != Connected, skipping\n", |
287 | __func__, dev->nodename, xenbus_strstate(dev->state)); | |
4bac07c9 JF |
288 | goto out; |
289 | } | |
290 | xenbus_switch_state(dev, XenbusStateClosing); | |
291 | timeout = wait_for_completion_timeout(&dev->down, timeout); | |
292 | if (!timeout) | |
283c0972 JP |
293 | pr_info("%s: %s timeout closing device\n", |
294 | __func__, dev->nodename); | |
4bac07c9 JF |
295 | out: |
296 | put_device(&dev->dev); | |
297 | } | |
2de06cc1 | 298 | EXPORT_SYMBOL_GPL(xenbus_dev_shutdown); |
4bac07c9 JF |
299 | |
300 | int xenbus_register_driver_common(struct xenbus_driver *drv, | |
95afae48 DV |
301 | struct xen_bus_type *bus, |
302 | struct module *owner, const char *mod_name) | |
4bac07c9 | 303 | { |
95afae48 | 304 | drv->driver.name = drv->name ? drv->name : drv->ids[0].devicetype; |
4bac07c9 | 305 | drv->driver.bus = &bus->bus; |
95afae48 DV |
306 | drv->driver.owner = owner; |
307 | drv->driver.mod_name = mod_name; | |
4bac07c9 JF |
308 | |
309 | return driver_register(&drv->driver); | |
310 | } | |
2de06cc1 | 311 | EXPORT_SYMBOL_GPL(xenbus_register_driver_common); |
4bac07c9 JF |
312 | |
313 | void xenbus_unregister_driver(struct xenbus_driver *drv) | |
314 | { | |
315 | driver_unregister(&drv->driver); | |
316 | } | |
317 | EXPORT_SYMBOL_GPL(xenbus_unregister_driver); | |
318 | ||
6913200a | 319 | struct xb_find_info { |
4bac07c9 JF |
320 | struct xenbus_device *dev; |
321 | const char *nodename; | |
322 | }; | |
323 | ||
324 | static int cmp_dev(struct device *dev, void *data) | |
325 | { | |
326 | struct xenbus_device *xendev = to_xenbus_device(dev); | |
327 | struct xb_find_info *info = data; | |
328 | ||
329 | if (!strcmp(xendev->nodename, info->nodename)) { | |
330 | info->dev = xendev; | |
331 | get_device(dev); | |
332 | return 1; | |
333 | } | |
334 | return 0; | |
335 | } | |
336 | ||
b8b0f559 KRW |
337 | static struct xenbus_device *xenbus_device_find(const char *nodename, |
338 | struct bus_type *bus) | |
4bac07c9 JF |
339 | { |
340 | struct xb_find_info info = { .dev = NULL, .nodename = nodename }; | |
341 | ||
342 | bus_for_each_dev(bus, NULL, &info, cmp_dev); | |
343 | return info.dev; | |
344 | } | |
345 | ||
346 | static int cleanup_dev(struct device *dev, void *data) | |
347 | { | |
348 | struct xenbus_device *xendev = to_xenbus_device(dev); | |
349 | struct xb_find_info *info = data; | |
350 | int len = strlen(info->nodename); | |
351 | ||
352 | DPRINTK("%s", info->nodename); | |
353 | ||
354 | /* Match the info->nodename path, or any subdirectory of that path. */ | |
355 | if (strncmp(xendev->nodename, info->nodename, len)) | |
356 | return 0; | |
357 | ||
358 | /* If the node name is longer, ensure it really is a subdirectory. */ | |
359 | if ((strlen(xendev->nodename) > len) && (xendev->nodename[len] != '/')) | |
360 | return 0; | |
361 | ||
362 | info->dev = xendev; | |
363 | get_device(dev); | |
364 | return 1; | |
365 | } | |
366 | ||
367 | static void xenbus_cleanup_devices(const char *path, struct bus_type *bus) | |
368 | { | |
369 | struct xb_find_info info = { .nodename = path }; | |
370 | ||
371 | do { | |
372 | info.dev = NULL; | |
373 | bus_for_each_dev(bus, NULL, &info, cleanup_dev); | |
374 | if (info.dev) { | |
375 | device_unregister(&info.dev->dev); | |
376 | put_device(&info.dev->dev); | |
377 | } | |
378 | } while (info.dev); | |
379 | } | |
380 | ||
381 | static void xenbus_dev_release(struct device *dev) | |
382 | { | |
383 | if (dev) | |
384 | kfree(to_xenbus_device(dev)); | |
385 | } | |
386 | ||
cc85e933 BB |
387 | static ssize_t nodename_show(struct device *dev, |
388 | struct device_attribute *attr, char *buf) | |
4bac07c9 JF |
389 | { |
390 | return sprintf(buf, "%s\n", to_xenbus_device(dev)->nodename); | |
391 | } | |
85dd9268 | 392 | static DEVICE_ATTR_RO(nodename); |
4bac07c9 | 393 | |
cc85e933 BB |
394 | static ssize_t devtype_show(struct device *dev, |
395 | struct device_attribute *attr, char *buf) | |
4bac07c9 JF |
396 | { |
397 | return sprintf(buf, "%s\n", to_xenbus_device(dev)->devicetype); | |
398 | } | |
85dd9268 | 399 | static DEVICE_ATTR_RO(devtype); |
4bac07c9 | 400 | |
cc85e933 BB |
401 | static ssize_t modalias_show(struct device *dev, |
402 | struct device_attribute *attr, char *buf) | |
d2f0c52b | 403 | { |
149bb2fa BB |
404 | return sprintf(buf, "%s:%s\n", dev->bus->name, |
405 | to_xenbus_device(dev)->devicetype); | |
d2f0c52b | 406 | } |
85dd9268 | 407 | static DEVICE_ATTR_RO(modalias); |
cc85e933 | 408 | |
85dd9268 GKH |
409 | static struct attribute *xenbus_dev_attrs[] = { |
410 | &dev_attr_nodename.attr, | |
411 | &dev_attr_devtype.attr, | |
412 | &dev_attr_modalias.attr, | |
413 | NULL, | |
cc85e933 | 414 | }; |
85dd9268 GKH |
415 | |
416 | static const struct attribute_group xenbus_dev_group = { | |
417 | .attrs = xenbus_dev_attrs, | |
418 | }; | |
419 | ||
420 | const struct attribute_group *xenbus_dev_groups[] = { | |
421 | &xenbus_dev_group, | |
422 | NULL, | |
423 | }; | |
424 | EXPORT_SYMBOL_GPL(xenbus_dev_groups); | |
4bac07c9 JF |
425 | |
426 | int xenbus_probe_node(struct xen_bus_type *bus, | |
427 | const char *type, | |
428 | const char *nodename) | |
429 | { | |
2a678cc5 | 430 | char devname[XEN_BUS_ID_SIZE]; |
4bac07c9 JF |
431 | int err; |
432 | struct xenbus_device *xendev; | |
433 | size_t stringlen; | |
434 | char *tmpstring; | |
435 | ||
436 | enum xenbus_state state = xenbus_read_driver_state(nodename); | |
437 | ||
438 | if (state != XenbusStateInitialising) { | |
439 | /* Device is not new, so ignore it. This can happen if a | |
440 | device is going away after switching to Closed. */ | |
441 | return 0; | |
442 | } | |
443 | ||
444 | stringlen = strlen(nodename) + 1 + strlen(type) + 1; | |
445 | xendev = kzalloc(sizeof(*xendev) + stringlen, GFP_KERNEL); | |
446 | if (!xendev) | |
447 | return -ENOMEM; | |
448 | ||
449 | xendev->state = XenbusStateInitialising; | |
450 | ||
451 | /* Copy the strings into the extra space. */ | |
452 | ||
453 | tmpstring = (char *)(xendev + 1); | |
454 | strcpy(tmpstring, nodename); | |
455 | xendev->nodename = tmpstring; | |
456 | ||
457 | tmpstring += strlen(tmpstring) + 1; | |
458 | strcpy(tmpstring, type); | |
459 | xendev->devicetype = tmpstring; | |
460 | init_completion(&xendev->down); | |
461 | ||
462 | xendev->dev.bus = &bus->bus; | |
463 | xendev->dev.release = xenbus_dev_release; | |
464 | ||
2a678cc5 | 465 | err = bus->get_bus_id(devname, xendev->nodename); |
4bac07c9 JF |
466 | if (err) |
467 | goto fail; | |
468 | ||
02aa2a37 | 469 | dev_set_name(&xendev->dev, "%s", devname); |
2a678cc5 | 470 | |
4bac07c9 JF |
471 | /* Register with generic device framework. */ |
472 | err = device_register(&xendev->dev); | |
473 | if (err) | |
474 | goto fail; | |
475 | ||
4bac07c9 | 476 | return 0; |
4bac07c9 JF |
477 | fail: |
478 | kfree(xendev); | |
479 | return err; | |
480 | } | |
2de06cc1 | 481 | EXPORT_SYMBOL_GPL(xenbus_probe_node); |
4bac07c9 JF |
482 | |
483 | static int xenbus_probe_device_type(struct xen_bus_type *bus, const char *type) | |
484 | { | |
485 | int err = 0; | |
486 | char **dir; | |
487 | unsigned int dir_n = 0; | |
488 | int i; | |
489 | ||
490 | dir = xenbus_directory(XBT_NIL, bus->root, type, &dir_n); | |
a39bda27 | 491 | if (IS_ERR(dir)) |
4bac07c9 JF |
492 | return PTR_ERR(dir); |
493 | ||
494 | for (i = 0; i < dir_n; i++) { | |
2de06cc1 | 495 | err = bus->probe(bus, type, dir[i]); |
a39bda27 | 496 | if (err) |
4bac07c9 JF |
497 | break; |
498 | } | |
a39bda27 | 499 | |
4bac07c9 JF |
500 | kfree(dir); |
501 | return err; | |
502 | } | |
503 | ||
504 | int xenbus_probe_devices(struct xen_bus_type *bus) | |
505 | { | |
506 | int err = 0; | |
507 | char **dir; | |
508 | unsigned int i, dir_n; | |
509 | ||
510 | dir = xenbus_directory(XBT_NIL, bus->root, "", &dir_n); | |
a39bda27 | 511 | if (IS_ERR(dir)) |
4bac07c9 JF |
512 | return PTR_ERR(dir); |
513 | ||
514 | for (i = 0; i < dir_n; i++) { | |
515 | err = xenbus_probe_device_type(bus, dir[i]); | |
a39bda27 | 516 | if (err) |
4bac07c9 JF |
517 | break; |
518 | } | |
a39bda27 | 519 | |
4bac07c9 JF |
520 | kfree(dir); |
521 | return err; | |
522 | } | |
2de06cc1 | 523 | EXPORT_SYMBOL_GPL(xenbus_probe_devices); |
4bac07c9 JF |
524 | |
525 | static unsigned int char_count(const char *str, char c) | |
526 | { | |
527 | unsigned int i, ret = 0; | |
528 | ||
529 | for (i = 0; str[i]; i++) | |
530 | if (str[i] == c) | |
531 | ret++; | |
532 | return ret; | |
533 | } | |
534 | ||
535 | static int strsep_len(const char *str, char c, unsigned int len) | |
536 | { | |
537 | unsigned int i; | |
538 | ||
539 | for (i = 0; str[i]; i++) | |
540 | if (str[i] == c) { | |
541 | if (len == 0) | |
542 | return i; | |
543 | len--; | |
544 | } | |
545 | return (len == 0) ? i : -ERANGE; | |
546 | } | |
547 | ||
548 | void xenbus_dev_changed(const char *node, struct xen_bus_type *bus) | |
549 | { | |
550 | int exists, rootlen; | |
551 | struct xenbus_device *dev; | |
2a678cc5 | 552 | char type[XEN_BUS_ID_SIZE]; |
4bac07c9 JF |
553 | const char *p, *root; |
554 | ||
555 | if (char_count(node, '/') < 2) | |
556 | return; | |
557 | ||
558 | exists = xenbus_exists(XBT_NIL, node, ""); | |
559 | if (!exists) { | |
560 | xenbus_cleanup_devices(node, &bus->bus); | |
561 | return; | |
562 | } | |
563 | ||
564 | /* backend/<type>/... or device/<type>/... */ | |
565 | p = strchr(node, '/') + 1; | |
2a678cc5 KS |
566 | snprintf(type, XEN_BUS_ID_SIZE, "%.*s", (int)strcspn(p, "/"), p); |
567 | type[XEN_BUS_ID_SIZE-1] = '\0'; | |
4bac07c9 JF |
568 | |
569 | rootlen = strsep_len(node, '/', bus->levels); | |
570 | if (rootlen < 0) | |
571 | return; | |
572 | root = kasprintf(GFP_KERNEL, "%.*s", rootlen, node); | |
573 | if (!root) | |
574 | return; | |
575 | ||
576 | dev = xenbus_device_find(root, &bus->bus); | |
577 | if (!dev) | |
578 | xenbus_probe_node(bus, type, root); | |
579 | else | |
580 | put_device(&dev->dev); | |
581 | ||
582 | kfree(root); | |
583 | } | |
c6a960ce | 584 | EXPORT_SYMBOL_GPL(xenbus_dev_changed); |
4bac07c9 | 585 | |
c7853aea | 586 | int xenbus_dev_suspend(struct device *dev) |
4bac07c9 JF |
587 | { |
588 | int err = 0; | |
589 | struct xenbus_driver *drv; | |
6bac7f9f IC |
590 | struct xenbus_device *xdev |
591 | = container_of(dev, struct xenbus_device, dev); | |
4bac07c9 | 592 | |
2de06cc1 | 593 | DPRINTK("%s", xdev->nodename); |
4bac07c9 JF |
594 | |
595 | if (dev->driver == NULL) | |
596 | return 0; | |
597 | drv = to_xenbus_driver(dev->driver); | |
4bac07c9 | 598 | if (drv->suspend) |
c7853aea | 599 | err = drv->suspend(xdev); |
4bac07c9 | 600 | if (err) |
283c0972 | 601 | pr_warn("suspend %s failed: %i\n", dev_name(dev), err); |
4bac07c9 JF |
602 | return 0; |
603 | } | |
2de06cc1 | 604 | EXPORT_SYMBOL_GPL(xenbus_dev_suspend); |
4bac07c9 | 605 | |
2de06cc1 | 606 | int xenbus_dev_resume(struct device *dev) |
4bac07c9 JF |
607 | { |
608 | int err; | |
609 | struct xenbus_driver *drv; | |
6bac7f9f IC |
610 | struct xenbus_device *xdev |
611 | = container_of(dev, struct xenbus_device, dev); | |
4bac07c9 | 612 | |
2de06cc1 | 613 | DPRINTK("%s", xdev->nodename); |
4bac07c9 JF |
614 | |
615 | if (dev->driver == NULL) | |
616 | return 0; | |
4bac07c9 | 617 | drv = to_xenbus_driver(dev->driver); |
4bac07c9 JF |
618 | err = talk_to_otherend(xdev); |
619 | if (err) { | |
283c0972 JP |
620 | pr_warn("resume (talk_to_otherend) %s failed: %i\n", |
621 | dev_name(dev), err); | |
4bac07c9 JF |
622 | return err; |
623 | } | |
624 | ||
625 | xdev->state = XenbusStateInitialising; | |
626 | ||
627 | if (drv->resume) { | |
628 | err = drv->resume(xdev); | |
629 | if (err) { | |
283c0972 | 630 | pr_warn("resume %s failed: %i\n", dev_name(dev), err); |
4bac07c9 JF |
631 | return err; |
632 | } | |
633 | } | |
634 | ||
635 | err = watch_otherend(xdev); | |
636 | if (err) { | |
283c0972 JP |
637 | pr_warn("resume (watch_otherend) %s failed: %d.\n", |
638 | dev_name(dev), err); | |
4bac07c9 JF |
639 | return err; |
640 | } | |
641 | ||
642 | return 0; | |
643 | } | |
2de06cc1 | 644 | EXPORT_SYMBOL_GPL(xenbus_dev_resume); |
4bac07c9 | 645 | |
c7853aea KS |
646 | int xenbus_dev_cancel(struct device *dev) |
647 | { | |
648 | /* Do nothing */ | |
649 | DPRINTK("cancel"); | |
650 | return 0; | |
651 | } | |
652 | EXPORT_SYMBOL_GPL(xenbus_dev_cancel); | |
653 | ||
4bac07c9 | 654 | /* A flag to determine if xenstored is 'ready' (i.e. has started) */ |
6913200a | 655 | int xenstored_ready; |
4bac07c9 JF |
656 | |
657 | ||
658 | int register_xenstore_notifier(struct notifier_block *nb) | |
659 | { | |
660 | int ret = 0; | |
661 | ||
a947f0f8 SS |
662 | if (xenstored_ready > 0) |
663 | ret = nb->notifier_call(nb, 0, NULL); | |
664 | else | |
665 | blocking_notifier_chain_register(&xenstore_chain, nb); | |
4bac07c9 JF |
666 | |
667 | return ret; | |
668 | } | |
669 | EXPORT_SYMBOL_GPL(register_xenstore_notifier); | |
670 | ||
671 | void unregister_xenstore_notifier(struct notifier_block *nb) | |
672 | { | |
673 | blocking_notifier_chain_unregister(&xenstore_chain, nb); | |
674 | } | |
675 | EXPORT_SYMBOL_GPL(unregister_xenstore_notifier); | |
676 | ||
677 | void xenbus_probe(struct work_struct *unused) | |
678 | { | |
a947f0f8 | 679 | xenstored_ready = 1; |
4bac07c9 | 680 | |
4bac07c9 JF |
681 | /* Notify others that xenstore is up */ |
682 | blocking_notifier_call_chain(&xenstore_chain, 0, NULL); | |
683 | } | |
183d03cc | 684 | EXPORT_SYMBOL_GPL(xenbus_probe); |
4bac07c9 | 685 | |
183d03cc SS |
686 | static int __init xenbus_probe_initcall(void) |
687 | { | |
688 | if (!xen_domain()) | |
689 | return -ENODEV; | |
690 | ||
691 | if (xen_initial_domain() || xen_hvm_domain()) | |
692 | return 0; | |
693 | ||
694 | xenbus_probe(NULL); | |
695 | return 0; | |
696 | } | |
697 | ||
698 | device_initcall(xenbus_probe_initcall); | |
699 | ||
e4184aaf DDG |
700 | /* Set up event channel for xenstored which is run as a local process |
701 | * (this is normally used only in dom0) | |
702 | */ | |
703 | static int __init xenstored_local_init(void) | |
4bac07c9 JF |
704 | { |
705 | int err = 0; | |
b37a56d6 | 706 | unsigned long page = 0; |
e4184aaf | 707 | struct evtchn_alloc_unbound alloc_unbound; |
4bac07c9 | 708 | |
e4184aaf DDG |
709 | /* Allocate Xenstore page */ |
710 | page = get_zeroed_page(GFP_KERNEL); | |
711 | if (!page) | |
712 | goto out_err; | |
4bac07c9 | 713 | |
5f51042f | 714 | xen_store_gfn = xen_start_info->store_mfn = virt_to_gfn((void *)page); |
4bac07c9 | 715 | |
e4184aaf DDG |
716 | /* Next allocate a local port which xenstored can bind to */ |
717 | alloc_unbound.dom = DOMID_SELF; | |
718 | alloc_unbound.remote_dom = DOMID_SELF; | |
b37a56d6 | 719 | |
e4184aaf DDG |
720 | err = HYPERVISOR_event_channel_op(EVTCHNOP_alloc_unbound, |
721 | &alloc_unbound); | |
722 | if (err == -ENOSYS) | |
723 | goto out_err; | |
b37a56d6 | 724 | |
e4184aaf DDG |
725 | BUG_ON(err); |
726 | xen_store_evtchn = xen_start_info->store_evtchn = | |
727 | alloc_unbound.port; | |
b37a56d6 | 728 | |
e4184aaf | 729 | return 0; |
b37a56d6 | 730 | |
e4184aaf DDG |
731 | out_err: |
732 | if (page != 0) | |
733 | free_page(page); | |
734 | return err; | |
735 | } | |
b37a56d6 | 736 | |
16f1cf3b BO |
737 | static int xenbus_resume_cb(struct notifier_block *nb, |
738 | unsigned long action, void *data) | |
739 | { | |
740 | int err = 0; | |
741 | ||
742 | if (xen_hvm_domain()) { | |
76ea3cb4 | 743 | uint64_t v = 0; |
16f1cf3b BO |
744 | |
745 | err = hvm_get_parameter(HVM_PARAM_STORE_EVTCHN, &v); | |
746 | if (!err && v) | |
747 | xen_store_evtchn = v; | |
748 | else | |
749 | pr_warn("Cannot update xenstore event channel: %d\n", | |
750 | err); | |
751 | } else | |
752 | xen_store_evtchn = xen_start_info->store_evtchn; | |
753 | ||
754 | return err; | |
755 | } | |
756 | ||
757 | static struct notifier_block xenbus_resume_nb = { | |
758 | .notifier_call = xenbus_resume_cb, | |
759 | }; | |
760 | ||
e4184aaf DDG |
761 | static int __init xenbus_init(void) |
762 | { | |
763 | int err = 0; | |
ecc635f9 | 764 | uint64_t v = 0; |
33c1174b | 765 | xen_store_domain_type = XS_UNKNOWN; |
b37a56d6 | 766 | |
e4184aaf DDG |
767 | if (!xen_domain()) |
768 | return -ENODEV; | |
769 | ||
2c5d37d3 DDG |
770 | xenbus_ring_ops_init(); |
771 | ||
ecc635f9 | 772 | if (xen_pv_domain()) |
33c1174b | 773 | xen_store_domain_type = XS_PV; |
ecc635f9 | 774 | if (xen_hvm_domain()) |
33c1174b | 775 | xen_store_domain_type = XS_HVM; |
ecc635f9 | 776 | if (xen_hvm_domain() && xen_initial_domain()) |
33c1174b | 777 | xen_store_domain_type = XS_LOCAL; |
ecc635f9 | 778 | if (xen_pv_domain() && !xen_start_info->store_evtchn) |
33c1174b | 779 | xen_store_domain_type = XS_LOCAL; |
ecc635f9 SS |
780 | if (xen_pv_domain() && xen_start_info->store_evtchn) |
781 | xenstored_ready = 1; | |
782 | ||
33c1174b AC |
783 | switch (xen_store_domain_type) { |
784 | case XS_LOCAL: | |
ecc635f9 SS |
785 | err = xenstored_local_init(); |
786 | if (err) | |
787 | goto out_error; | |
5f51042f | 788 | xen_store_interface = gfn_to_virt(xen_store_gfn); |
ecc635f9 | 789 | break; |
33c1174b | 790 | case XS_PV: |
ecc635f9 | 791 | xen_store_evtchn = xen_start_info->store_evtchn; |
5f51042f JG |
792 | xen_store_gfn = xen_start_info->store_mfn; |
793 | xen_store_interface = gfn_to_virt(xen_store_gfn); | |
ecc635f9 | 794 | break; |
33c1174b | 795 | case XS_HVM: |
e4184aaf DDG |
796 | err = hvm_get_parameter(HVM_PARAM_STORE_EVTCHN, &v); |
797 | if (err) | |
798 | goto out_error; | |
799 | xen_store_evtchn = (int)v; | |
800 | err = hvm_get_parameter(HVM_PARAM_STORE_PFN, &v); | |
801 | if (err) | |
802 | goto out_error; | |
5f51042f | 803 | xen_store_gfn = (unsigned long)v; |
ecc635f9 | 804 | xen_store_interface = |
7d567928 JG |
805 | xen_remap(xen_store_gfn << XEN_PAGE_SHIFT, |
806 | XEN_PAGE_SIZE); | |
ecc635f9 SS |
807 | break; |
808 | default: | |
809 | pr_warn("Xenstore state unknown\n"); | |
810 | break; | |
4bac07c9 | 811 | } |
4bac07c9 JF |
812 | |
813 | /* Initialize the interface to xenstore. */ | |
814 | err = xs_init(); | |
815 | if (err) { | |
283c0972 | 816 | pr_warn("Error initializing xenstore comms: %i\n", err); |
2de06cc1 | 817 | goto out_error; |
4bac07c9 JF |
818 | } |
819 | ||
16f1cf3b BO |
820 | if ((xen_store_domain_type != XS_LOCAL) && |
821 | (xen_store_domain_type != XS_UNKNOWN)) | |
822 | xen_resume_notifier_register(&xenbus_resume_nb); | |
823 | ||
1107ba88 AZ |
824 | #ifdef CONFIG_XEN_COMPAT_XENFS |
825 | /* | |
826 | * Create xenfs mountpoint in /proc for compatibility with | |
827 | * utilities that expect to find "xenbus" under "/proc/xen". | |
828 | */ | |
829 | proc_mkdir("xen", NULL); | |
830 | #endif | |
831 | ||
6913200a | 832 | out_error: |
4bac07c9 JF |
833 | return err; |
834 | } | |
835 | ||
183d03cc | 836 | postcore_initcall(xenbus_init); |
4bac07c9 JF |
837 | |
838 | MODULE_LICENSE("GPL"); |