blob: 33a31cfef55dd407c829f29a8c3b71379442799a [file] [log] [blame]
Jeremy Fitzhardinge4bac07c2007-07-17 18:37:06 -07001/******************************************************************************
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
Joe Perches283c0972013-06-28 03:21:41 -070033#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
34
Jeremy Fitzhardinge4bac07c2007-07-17 18:37:06 -070035#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>
Alex Zeffertt1107ba82009-01-07 18:07:11 -080045#include <linux/proc_fs.h>
Jeremy Fitzhardinge4bac07c2007-07-17 18:37:06 -070046#include <linux/notifier.h>
47#include <linux/kthread.h>
48#include <linux/mutex.h>
49#include <linux/io.h>
Tejun Heo5a0e3ad2010-03-24 17:04:11 +090050#include <linux/slab.h>
Paul Gortmaker72ee5112011-07-03 16:20:57 -040051#include <linux/module.h>
Jeremy Fitzhardinge4bac07c2007-07-17 18:37:06 -070052
53#include <asm/page.h>
54#include <asm/pgtable.h>
55#include <asm/xen/hypervisor.h>
Jeremy Fitzhardinge1ccbf532009-10-06 15:11:14 -070056
57#include <xen/xen.h>
Jeremy Fitzhardinge4bac07c2007-07-17 18:37:06 -070058#include <xen/xenbus.h>
59#include <xen/events.h>
Boris Ostrovsky16f1cf32015-04-29 17:10:13 -040060#include <xen/xen-ops.h>
Jeremy Fitzhardinge4bac07c2007-07-17 18:37:06 -070061#include <xen/page.h>
62
Sheng Yangbee6ab52010-05-14 12:39:33 +010063#include <xen/hvm.h>
64
Jeremy Fitzhardinge4bac07c2007-07-17 18:37:06 -070065#include "xenbus_comms.h"
66#include "xenbus_probe.h"
67
Alex Zeffertt1107ba82009-01-07 18:07:11 -080068
Jeremy Fitzhardinge4bac07c2007-07-17 18:37:06 -070069int xen_store_evtchn;
Jeremy Fitzhardinge8e3e9992009-03-21 23:51:26 -070070EXPORT_SYMBOL_GPL(xen_store_evtchn);
Alex Zeffertt1107ba82009-01-07 18:07:11 -080071
Jeremy Fitzhardinge4bac07c2007-07-17 18:37:06 -070072struct xenstore_domain_interface *xen_store_interface;
Jeremy Fitzhardinge8e3e9992009-03-21 23:51:26 -070073EXPORT_SYMBOL_GPL(xen_store_interface);
74
Aurelien Chartier33c11742013-05-28 18:09:55 +010075enum xenstore_init xen_store_domain_type;
76EXPORT_SYMBOL_GPL(xen_store_domain_type);
77
Julien Grall5f510422015-08-07 17:34:42 +010078static unsigned long xen_store_gfn;
Jeremy Fitzhardinge4bac07c2007-07-17 18:37:06 -070079
80static BLOCKING_NOTIFIER_HEAD(xenstore_chain);
81
Jeremy Fitzhardinge4bac07c2007-07-17 18:37:06 -070082/* If something in array of ids matches this device, return it. */
83static const struct xenbus_device_id *
84match_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
93int 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}
Ian Campbell2de06cc2009-02-09 12:05:51 -0800102EXPORT_SYMBOL_GPL(xenbus_match);
Jeremy Fitzhardinge4bac07c2007-07-17 18:37:06 -0700103
Ian Campbell2de06cc2009-02-09 12:05:51 -0800104
Jeremy Fitzhardinge4bac07c2007-07-17 18:37:06 -0700105static void free_otherend_details(struct xenbus_device *dev)
106{
107 kfree(dev->otherend);
108 dev->otherend = NULL;
109}
110
111
112static 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
Ian Campbell2de06cc2009-02-09 12:05:51 -0800122static 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
134static int watch_otherend(struct xenbus_device *dev)
135{
Ian Campbell6bac7f92010-12-10 14:39:15 +0000136 struct xen_bus_type *bus =
137 container_of(dev->dev.bus, struct xen_bus_type, bus);
Ian Campbell2de06cc2009-02-09 12:05:51 -0800138
Ian Campbell6bac7f92010-12-10 14:39:15 +0000139 return xenbus_watch_pathfmt(dev, &dev->otherend_watch,
140 bus->otherend_changed,
Ian Campbell2de06cc2009-02-09 12:05:51 -0800141 "%s/%s", dev->otherend, "state");
142}
143
144
145int xenbus_read_otherend_details(struct xenbus_device *xendev,
Jeremy Fitzhardinge4bac07c2007-07-17 18:37:06 -0700146 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}
Ian Campbell2de06cc2009-02-09 12:05:51 -0800170EXPORT_SYMBOL_GPL(xenbus_read_otherend_details);
Jeremy Fitzhardinge4bac07c2007-07-17 18:37:06 -0700171
Ian Campbell2de06cc2009-02-09 12:05:51 -0800172void xenbus_otherend_changed(struct xenbus_watch *watch,
173 const char **vec, unsigned int len,
174 int ignore_on_shutdown)
Jeremy Fitzhardinge4bac07c2007-07-17 18:37:06 -0700175{
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))) {
Joe Perches898eb712007-10-18 03:06:30 -0700186 dev_dbg(&dev->dev, "Ignoring watch at %s\n",
187 vec[XS_WATCH_PATH]);
Jeremy Fitzhardinge4bac07c2007-07-17 18:37:06 -0700188 return;
189 }
190
191 state = xenbus_read_driver_state(dev->otherend);
192
Joe Perches898eb712007-10-18 03:06:30 -0700193 dev_dbg(&dev->dev, "state is %d, (%s), %s, %s\n",
Jeremy Fitzhardinge4bac07c2007-07-17 18:37:06 -0700194 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) {
Ian Campbell2de06cc2009-02-09 12:05:51 -0800202 if (ignore_on_shutdown && (state == XenbusStateClosing))
Jeremy Fitzhardinge4bac07c2007-07-17 18:37:06 -0700203 xenbus_frontend_closed(dev);
204 return;
205 }
206
207 if (drv->otherend_changed)
208 drv->otherend_changed(dev, state);
209}
Ian Campbell2de06cc2009-02-09 12:05:51 -0800210EXPORT_SYMBOL_GPL(xenbus_otherend_changed);
Jeremy Fitzhardinge4bac07c2007-07-17 18:37:06 -0700211
212int 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;
251fail:
252 xenbus_dev_error(dev, err, "xenbus_dev_probe on %s", dev->nodename);
253 xenbus_switch_state(dev, XenbusStateClosed);
Jeremy Fitzhardinge7432e4b2009-10-29 14:19:42 -0700254 return err;
Jeremy Fitzhardinge4bac07c2007-07-17 18:37:06 -0700255}
Ian Campbell2de06cc2009-02-09 12:05:51 -0800256EXPORT_SYMBOL_GPL(xenbus_dev_probe);
Jeremy Fitzhardinge4bac07c2007-07-17 18:37:06 -0700257
258int 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);
Jeremy Fitzhardinge4bac07c2007-07-17 18:37:06 -0700266
267 if (drv->remove)
268 drv->remove(dev);
269
Jan Beulichbd0d5aa2012-03-05 17:11:31 +0000270 free_otherend_details(dev);
271
Jeremy Fitzhardinge4bac07c2007-07-17 18:37:06 -0700272 xenbus_switch_state(dev, XenbusStateClosed);
273 return 0;
274}
Ian Campbell2de06cc2009-02-09 12:05:51 -0800275EXPORT_SYMBOL_GPL(xenbus_dev_remove);
Jeremy Fitzhardinge4bac07c2007-07-17 18:37:06 -0700276
Ian Campbell2de06cc2009-02-09 12:05:51 -0800277void xenbus_dev_shutdown(struct device *_dev)
Jeremy Fitzhardinge4bac07c2007-07-17 18:37:06 -0700278{
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) {
Joe Perches283c0972013-06-28 03:21:41 -0700286 pr_info("%s: %s: %s != Connected, skipping\n",
287 __func__, dev->nodename, xenbus_strstate(dev->state));
Jeremy Fitzhardinge4bac07c2007-07-17 18:37:06 -0700288 goto out;
289 }
290 xenbus_switch_state(dev, XenbusStateClosing);
291 timeout = wait_for_completion_timeout(&dev->down, timeout);
292 if (!timeout)
Joe Perches283c0972013-06-28 03:21:41 -0700293 pr_info("%s: %s timeout closing device\n",
294 __func__, dev->nodename);
Jeremy Fitzhardinge4bac07c2007-07-17 18:37:06 -0700295 out:
296 put_device(&dev->dev);
297}
Ian Campbell2de06cc2009-02-09 12:05:51 -0800298EXPORT_SYMBOL_GPL(xenbus_dev_shutdown);
Jeremy Fitzhardinge4bac07c2007-07-17 18:37:06 -0700299
300int xenbus_register_driver_common(struct xenbus_driver *drv,
David Vrabel95afae42014-09-08 17:30:41 +0100301 struct xen_bus_type *bus,
302 struct module *owner, const char *mod_name)
Jeremy Fitzhardinge4bac07c2007-07-17 18:37:06 -0700303{
David Vrabel95afae42014-09-08 17:30:41 +0100304 drv->driver.name = drv->name ? drv->name : drv->ids[0].devicetype;
Jeremy Fitzhardinge4bac07c2007-07-17 18:37:06 -0700305 drv->driver.bus = &bus->bus;
David Vrabel95afae42014-09-08 17:30:41 +0100306 drv->driver.owner = owner;
307 drv->driver.mod_name = mod_name;
Jeremy Fitzhardinge4bac07c2007-07-17 18:37:06 -0700308
309 return driver_register(&drv->driver);
310}
Ian Campbell2de06cc2009-02-09 12:05:51 -0800311EXPORT_SYMBOL_GPL(xenbus_register_driver_common);
Jeremy Fitzhardinge4bac07c2007-07-17 18:37:06 -0700312
313void xenbus_unregister_driver(struct xenbus_driver *drv)
314{
315 driver_unregister(&drv->driver);
316}
317EXPORT_SYMBOL_GPL(xenbus_unregister_driver);
318
Ruslan Pisarev69132002011-07-26 14:17:23 +0300319struct xb_find_info {
Jeremy Fitzhardinge4bac07c2007-07-17 18:37:06 -0700320 struct xenbus_device *dev;
321 const char *nodename;
322};
323
324static 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
Konrad Rzeszutek Wilkb8b0f552012-08-21 14:49:34 -0400337static struct xenbus_device *xenbus_device_find(const char *nodename,
338 struct bus_type *bus)
Jeremy Fitzhardinge4bac07c2007-07-17 18:37:06 -0700339{
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
346static 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
367static 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
381static void xenbus_dev_release(struct device *dev)
382{
383 if (dev)
384 kfree(to_xenbus_device(dev));
385}
386
Bastian Blankcc85e932011-06-29 14:39:26 +0200387static ssize_t nodename_show(struct device *dev,
388 struct device_attribute *attr, char *buf)
Jeremy Fitzhardinge4bac07c2007-07-17 18:37:06 -0700389{
390 return sprintf(buf, "%s\n", to_xenbus_device(dev)->nodename);
391}
Greg Kroah-Hartman85dd9262013-10-06 23:55:49 -0700392static DEVICE_ATTR_RO(nodename);
Jeremy Fitzhardinge4bac07c2007-07-17 18:37:06 -0700393
Bastian Blankcc85e932011-06-29 14:39:26 +0200394static ssize_t devtype_show(struct device *dev,
395 struct device_attribute *attr, char *buf)
Jeremy Fitzhardinge4bac07c2007-07-17 18:37:06 -0700396{
397 return sprintf(buf, "%s\n", to_xenbus_device(dev)->devicetype);
398}
Greg Kroah-Hartman85dd9262013-10-06 23:55:49 -0700399static DEVICE_ATTR_RO(devtype);
Jeremy Fitzhardinge4bac07c2007-07-17 18:37:06 -0700400
Bastian Blankcc85e932011-06-29 14:39:26 +0200401static ssize_t modalias_show(struct device *dev,
402 struct device_attribute *attr, char *buf)
Mark McLoughlind2f0c522008-04-02 10:54:05 -0700403{
Bastian Blank149bb2f2011-06-29 14:40:08 +0200404 return sprintf(buf, "%s:%s\n", dev->bus->name,
405 to_xenbus_device(dev)->devicetype);
Mark McLoughlind2f0c522008-04-02 10:54:05 -0700406}
Greg Kroah-Hartman85dd9262013-10-06 23:55:49 -0700407static DEVICE_ATTR_RO(modalias);
Bastian Blankcc85e932011-06-29 14:39:26 +0200408
Greg Kroah-Hartman85dd9262013-10-06 23:55:49 -0700409static struct attribute *xenbus_dev_attrs[] = {
410 &dev_attr_nodename.attr,
411 &dev_attr_devtype.attr,
412 &dev_attr_modalias.attr,
413 NULL,
Bastian Blankcc85e932011-06-29 14:39:26 +0200414};
Greg Kroah-Hartman85dd9262013-10-06 23:55:49 -0700415
416static const struct attribute_group xenbus_dev_group = {
417 .attrs = xenbus_dev_attrs,
418};
419
420const struct attribute_group *xenbus_dev_groups[] = {
421 &xenbus_dev_group,
422 NULL,
423};
424EXPORT_SYMBOL_GPL(xenbus_dev_groups);
Jeremy Fitzhardinge4bac07c2007-07-17 18:37:06 -0700425
426int xenbus_probe_node(struct xen_bus_type *bus,
427 const char *type,
428 const char *nodename)
429{
Kay Sievers2a678cc2009-01-06 10:44:34 -0800430 char devname[XEN_BUS_ID_SIZE];
Jeremy Fitzhardinge4bac07c2007-07-17 18:37:06 -0700431 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
Kay Sievers2a678cc2009-01-06 10:44:34 -0800465 err = bus->get_bus_id(devname, xendev->nodename);
Jeremy Fitzhardinge4bac07c2007-07-17 18:37:06 -0700466 if (err)
467 goto fail;
468
Kees Cook02aa2a32013-07-03 15:04:56 -0700469 dev_set_name(&xendev->dev, "%s", devname);
Kay Sievers2a678cc2009-01-06 10:44:34 -0800470
Jeremy Fitzhardinge4bac07c2007-07-17 18:37:06 -0700471 /* Register with generic device framework. */
472 err = device_register(&xendev->dev);
473 if (err)
474 goto fail;
475
Jeremy Fitzhardinge4bac07c2007-07-17 18:37:06 -0700476 return 0;
Jeremy Fitzhardinge4bac07c2007-07-17 18:37:06 -0700477fail:
478 kfree(xendev);
479 return err;
480}
Ian Campbell2de06cc2009-02-09 12:05:51 -0800481EXPORT_SYMBOL_GPL(xenbus_probe_node);
Jeremy Fitzhardinge4bac07c2007-07-17 18:37:06 -0700482
483static 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);
Jeremy Fitzhardingea39bda22010-03-29 14:38:12 -0700491 if (IS_ERR(dir))
Jeremy Fitzhardinge4bac07c2007-07-17 18:37:06 -0700492 return PTR_ERR(dir);
493
494 for (i = 0; i < dir_n; i++) {
Ian Campbell2de06cc2009-02-09 12:05:51 -0800495 err = bus->probe(bus, type, dir[i]);
Jeremy Fitzhardingea39bda22010-03-29 14:38:12 -0700496 if (err)
Jeremy Fitzhardinge4bac07c2007-07-17 18:37:06 -0700497 break;
498 }
Jeremy Fitzhardingea39bda22010-03-29 14:38:12 -0700499
Jeremy Fitzhardinge4bac07c2007-07-17 18:37:06 -0700500 kfree(dir);
501 return err;
502}
503
504int 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);
Jeremy Fitzhardingea39bda22010-03-29 14:38:12 -0700511 if (IS_ERR(dir))
Jeremy Fitzhardinge4bac07c2007-07-17 18:37:06 -0700512 return PTR_ERR(dir);
513
514 for (i = 0; i < dir_n; i++) {
515 err = xenbus_probe_device_type(bus, dir[i]);
Jeremy Fitzhardingea39bda22010-03-29 14:38:12 -0700516 if (err)
Jeremy Fitzhardinge4bac07c2007-07-17 18:37:06 -0700517 break;
518 }
Jeremy Fitzhardingea39bda22010-03-29 14:38:12 -0700519
Jeremy Fitzhardinge4bac07c2007-07-17 18:37:06 -0700520 kfree(dir);
521 return err;
522}
Ian Campbell2de06cc2009-02-09 12:05:51 -0800523EXPORT_SYMBOL_GPL(xenbus_probe_devices);
Jeremy Fitzhardinge4bac07c2007-07-17 18:37:06 -0700524
525static 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
535static 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
548void xenbus_dev_changed(const char *node, struct xen_bus_type *bus)
549{
550 int exists, rootlen;
551 struct xenbus_device *dev;
Kay Sievers2a678cc2009-01-06 10:44:34 -0800552 char type[XEN_BUS_ID_SIZE];
Jeremy Fitzhardinge4bac07c2007-07-17 18:37:06 -0700553 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;
Kay Sievers2a678cc2009-01-06 10:44:34 -0800566 snprintf(type, XEN_BUS_ID_SIZE, "%.*s", (int)strcspn(p, "/"), p);
567 type[XEN_BUS_ID_SIZE-1] = '\0';
Jeremy Fitzhardinge4bac07c2007-07-17 18:37:06 -0700568
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}
Jeremy Fitzhardingec6a960c2009-02-09 12:05:53 -0800584EXPORT_SYMBOL_GPL(xenbus_dev_changed);
Jeremy Fitzhardinge4bac07c2007-07-17 18:37:06 -0700585
Kazuhiro SUZUKIc7853ae2011-02-18 14:43:07 -0800586int xenbus_dev_suspend(struct device *dev)
Jeremy Fitzhardinge4bac07c2007-07-17 18:37:06 -0700587{
588 int err = 0;
589 struct xenbus_driver *drv;
Ian Campbell6bac7f92010-12-10 14:39:15 +0000590 struct xenbus_device *xdev
591 = container_of(dev, struct xenbus_device, dev);
Jeremy Fitzhardinge4bac07c2007-07-17 18:37:06 -0700592
Ian Campbell2de06cc2009-02-09 12:05:51 -0800593 DPRINTK("%s", xdev->nodename);
Jeremy Fitzhardinge4bac07c2007-07-17 18:37:06 -0700594
595 if (dev->driver == NULL)
596 return 0;
597 drv = to_xenbus_driver(dev->driver);
Jeremy Fitzhardinge4bac07c2007-07-17 18:37:06 -0700598 if (drv->suspend)
Kazuhiro SUZUKIc7853ae2011-02-18 14:43:07 -0800599 err = drv->suspend(xdev);
Jeremy Fitzhardinge4bac07c2007-07-17 18:37:06 -0700600 if (err)
Joe Perches283c0972013-06-28 03:21:41 -0700601 pr_warn("suspend %s failed: %i\n", dev_name(dev), err);
Jeremy Fitzhardinge4bac07c2007-07-17 18:37:06 -0700602 return 0;
603}
Ian Campbell2de06cc2009-02-09 12:05:51 -0800604EXPORT_SYMBOL_GPL(xenbus_dev_suspend);
Jeremy Fitzhardinge4bac07c2007-07-17 18:37:06 -0700605
Ian Campbell2de06cc2009-02-09 12:05:51 -0800606int xenbus_dev_resume(struct device *dev)
Jeremy Fitzhardinge4bac07c2007-07-17 18:37:06 -0700607{
608 int err;
609 struct xenbus_driver *drv;
Ian Campbell6bac7f92010-12-10 14:39:15 +0000610 struct xenbus_device *xdev
611 = container_of(dev, struct xenbus_device, dev);
Jeremy Fitzhardinge4bac07c2007-07-17 18:37:06 -0700612
Ian Campbell2de06cc2009-02-09 12:05:51 -0800613 DPRINTK("%s", xdev->nodename);
Jeremy Fitzhardinge4bac07c2007-07-17 18:37:06 -0700614
615 if (dev->driver == NULL)
616 return 0;
Jeremy Fitzhardinge4bac07c2007-07-17 18:37:06 -0700617 drv = to_xenbus_driver(dev->driver);
Jeremy Fitzhardinge4bac07c2007-07-17 18:37:06 -0700618 err = talk_to_otherend(xdev);
619 if (err) {
Joe Perches283c0972013-06-28 03:21:41 -0700620 pr_warn("resume (talk_to_otherend) %s failed: %i\n",
621 dev_name(dev), err);
Jeremy Fitzhardinge4bac07c2007-07-17 18:37:06 -0700622 return err;
623 }
624
625 xdev->state = XenbusStateInitialising;
626
627 if (drv->resume) {
628 err = drv->resume(xdev);
629 if (err) {
Joe Perches283c0972013-06-28 03:21:41 -0700630 pr_warn("resume %s failed: %i\n", dev_name(dev), err);
Jeremy Fitzhardinge4bac07c2007-07-17 18:37:06 -0700631 return err;
632 }
633 }
634
635 err = watch_otherend(xdev);
636 if (err) {
Joe Perches283c0972013-06-28 03:21:41 -0700637 pr_warn("resume (watch_otherend) %s failed: %d.\n",
638 dev_name(dev), err);
Jeremy Fitzhardinge4bac07c2007-07-17 18:37:06 -0700639 return err;
640 }
641
642 return 0;
643}
Ian Campbell2de06cc2009-02-09 12:05:51 -0800644EXPORT_SYMBOL_GPL(xenbus_dev_resume);
Jeremy Fitzhardinge4bac07c2007-07-17 18:37:06 -0700645
Kazuhiro SUZUKIc7853ae2011-02-18 14:43:07 -0800646int xenbus_dev_cancel(struct device *dev)
647{
648 /* Do nothing */
649 DPRINTK("cancel");
650 return 0;
651}
652EXPORT_SYMBOL_GPL(xenbus_dev_cancel);
653
Jeremy Fitzhardinge4bac07c2007-07-17 18:37:06 -0700654/* A flag to determine if xenstored is 'ready' (i.e. has started) */
Ruslan Pisarev69132002011-07-26 14:17:23 +0300655int xenstored_ready;
Jeremy Fitzhardinge4bac07c2007-07-17 18:37:06 -0700656
657
658int register_xenstore_notifier(struct notifier_block *nb)
659{
660 int ret = 0;
661
Stefano Stabellinia947f0f2010-10-04 16:10:06 +0100662 if (xenstored_ready > 0)
663 ret = nb->notifier_call(nb, 0, NULL);
664 else
665 blocking_notifier_chain_register(&xenstore_chain, nb);
Jeremy Fitzhardinge4bac07c2007-07-17 18:37:06 -0700666
667 return ret;
668}
669EXPORT_SYMBOL_GPL(register_xenstore_notifier);
670
671void unregister_xenstore_notifier(struct notifier_block *nb)
672{
673 blocking_notifier_chain_unregister(&xenstore_chain, nb);
674}
675EXPORT_SYMBOL_GPL(unregister_xenstore_notifier);
676
677void xenbus_probe(struct work_struct *unused)
678{
Stefano Stabellinia947f0f2010-10-04 16:10:06 +0100679 xenstored_ready = 1;
Jeremy Fitzhardinge4bac07c2007-07-17 18:37:06 -0700680
Jeremy Fitzhardinge4bac07c2007-07-17 18:37:06 -0700681 /* Notify others that xenstore is up */
682 blocking_notifier_call_chain(&xenstore_chain, 0, NULL);
683}
Stefano Stabellini183d03c2010-05-17 17:08:21 +0100684EXPORT_SYMBOL_GPL(xenbus_probe);
Jeremy Fitzhardinge4bac07c2007-07-17 18:37:06 -0700685
Stefano Stabellini183d03c2010-05-17 17:08:21 +0100686static 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
698device_initcall(xenbus_probe_initcall);
699
Daniel De Graafe4184aa2011-10-13 16:07:08 -0400700/* Set up event channel for xenstored which is run as a local process
701 * (this is normally used only in dom0)
702 */
703static int __init xenstored_local_init(void)
Jeremy Fitzhardinge4bac07c2007-07-17 18:37:06 -0700704{
705 int err = 0;
Juan Quintelab37a56d2010-09-02 14:53:56 +0100706 unsigned long page = 0;
Daniel De Graafe4184aa2011-10-13 16:07:08 -0400707 struct evtchn_alloc_unbound alloc_unbound;
Jeremy Fitzhardinge4bac07c2007-07-17 18:37:06 -0700708
Daniel De Graafe4184aa2011-10-13 16:07:08 -0400709 /* Allocate Xenstore page */
710 page = get_zeroed_page(GFP_KERNEL);
711 if (!page)
712 goto out_err;
Jeremy Fitzhardinge4bac07c2007-07-17 18:37:06 -0700713
Julien Grall5f510422015-08-07 17:34:42 +0100714 xen_store_gfn = xen_start_info->store_mfn = virt_to_gfn((void *)page);
Daniel De Graafe4184aa2011-10-13 16:07:08 -0400715
716 /* Next allocate a local port which xenstored can bind to */
717 alloc_unbound.dom = DOMID_SELF;
718 alloc_unbound.remote_dom = DOMID_SELF;
719
720 err = HYPERVISOR_event_channel_op(EVTCHNOP_alloc_unbound,
721 &alloc_unbound);
722 if (err == -ENOSYS)
723 goto out_err;
724
725 BUG_ON(err);
726 xen_store_evtchn = xen_start_info->store_evtchn =
727 alloc_unbound.port;
728
729 return 0;
730
731 out_err:
732 if (page != 0)
733 free_page(page);
734 return err;
735}
736
Boris Ostrovsky16f1cf32015-04-29 17:10:13 -0400737static 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()) {
Jan Beulich76ea3cb2015-05-28 09:26:37 +0100743 uint64_t v = 0;
Boris Ostrovsky16f1cf32015-04-29 17:10:13 -0400744
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
757static struct notifier_block xenbus_resume_nb = {
758 .notifier_call = xenbus_resume_cb,
759};
760
Daniel De Graafe4184aa2011-10-13 16:07:08 -0400761static int __init xenbus_init(void)
762{
763 int err = 0;
Stefano Stabelliniecc635f2012-09-14 12:13:12 +0100764 uint64_t v = 0;
Aurelien Chartier33c11742013-05-28 18:09:55 +0100765 xen_store_domain_type = XS_UNKNOWN;
Daniel De Graafe4184aa2011-10-13 16:07:08 -0400766
Jeremy Fitzhardinge6e833582008-08-19 13:16:17 -0700767 if (!xen_domain())
Daniel De Graafe4184aa2011-10-13 16:07:08 -0400768 return -ENODEV;
Jeremy Fitzhardinge4bac07c2007-07-17 18:37:06 -0700769
Daniel De Graaf2c5d37d2011-12-19 14:55:14 -0500770 xenbus_ring_ops_init();
771
Stefano Stabelliniecc635f2012-09-14 12:13:12 +0100772 if (xen_pv_domain())
Aurelien Chartier33c11742013-05-28 18:09:55 +0100773 xen_store_domain_type = XS_PV;
Stefano Stabelliniecc635f2012-09-14 12:13:12 +0100774 if (xen_hvm_domain())
Aurelien Chartier33c11742013-05-28 18:09:55 +0100775 xen_store_domain_type = XS_HVM;
Stefano Stabelliniecc635f2012-09-14 12:13:12 +0100776 if (xen_hvm_domain() && xen_initial_domain())
Aurelien Chartier33c11742013-05-28 18:09:55 +0100777 xen_store_domain_type = XS_LOCAL;
Stefano Stabelliniecc635f2012-09-14 12:13:12 +0100778 if (xen_pv_domain() && !xen_start_info->store_evtchn)
Aurelien Chartier33c11742013-05-28 18:09:55 +0100779 xen_store_domain_type = XS_LOCAL;
Stefano Stabelliniecc635f2012-09-14 12:13:12 +0100780 if (xen_pv_domain() && xen_start_info->store_evtchn)
781 xenstored_ready = 1;
782
Aurelien Chartier33c11742013-05-28 18:09:55 +0100783 switch (xen_store_domain_type) {
784 case XS_LOCAL:
Stefano Stabelliniecc635f2012-09-14 12:13:12 +0100785 err = xenstored_local_init();
786 if (err)
787 goto out_error;
Julien Grall5f510422015-08-07 17:34:42 +0100788 xen_store_interface = gfn_to_virt(xen_store_gfn);
Stefano Stabelliniecc635f2012-09-14 12:13:12 +0100789 break;
Aurelien Chartier33c11742013-05-28 18:09:55 +0100790 case XS_PV:
Stefano Stabelliniecc635f2012-09-14 12:13:12 +0100791 xen_store_evtchn = xen_start_info->store_evtchn;
Julien Grall5f510422015-08-07 17:34:42 +0100792 xen_store_gfn = xen_start_info->store_mfn;
793 xen_store_interface = gfn_to_virt(xen_store_gfn);
Stefano Stabelliniecc635f2012-09-14 12:13:12 +0100794 break;
Aurelien Chartier33c11742013-05-28 18:09:55 +0100795 case XS_HVM:
Daniel De Graafe4184aa2011-10-13 16:07:08 -0400796 err = hvm_get_parameter(HVM_PARAM_STORE_EVTCHN, &v);
797 if (err)
Juan Quintelab37a56d2010-09-02 14:53:56 +0100798 goto out_error;
Daniel De Graafe4184aa2011-10-13 16:07:08 -0400799 xen_store_evtchn = (int)v;
800 err = hvm_get_parameter(HVM_PARAM_STORE_PFN, &v);
801 if (err)
Juan Quintelab37a56d2010-09-02 14:53:56 +0100802 goto out_error;
Julien Grall5f510422015-08-07 17:34:42 +0100803 xen_store_gfn = (unsigned long)v;
Stefano Stabelliniecc635f2012-09-14 12:13:12 +0100804 xen_store_interface =
Julien Grall7d567922015-05-05 16:38:27 +0100805 xen_remap(xen_store_gfn << XEN_PAGE_SHIFT,
806 XEN_PAGE_SIZE);
Stefano Stabelliniecc635f2012-09-14 12:13:12 +0100807 break;
808 default:
809 pr_warn("Xenstore state unknown\n");
810 break;
Jeremy Fitzhardinge4bac07c2007-07-17 18:37:06 -0700811 }
Jeremy Fitzhardinge4bac07c2007-07-17 18:37:06 -0700812
813 /* Initialize the interface to xenstore. */
814 err = xs_init();
815 if (err) {
Joe Perches283c0972013-06-28 03:21:41 -0700816 pr_warn("Error initializing xenstore comms: %i\n", err);
Ian Campbell2de06cc2009-02-09 12:05:51 -0800817 goto out_error;
Jeremy Fitzhardinge4bac07c2007-07-17 18:37:06 -0700818 }
819
Boris Ostrovsky16f1cf32015-04-29 17:10:13 -0400820 if ((xen_store_domain_type != XS_LOCAL) &&
821 (xen_store_domain_type != XS_UNKNOWN))
822 xen_resume_notifier_register(&xenbus_resume_nb);
823
Alex Zeffertt1107ba82009-01-07 18:07:11 -0800824#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
Ruslan Pisarev69132002011-07-26 14:17:23 +0300832out_error:
Jeremy Fitzhardinge4bac07c2007-07-17 18:37:06 -0700833 return err;
834}
835
Stefano Stabellini183d03c2010-05-17 17:08:21 +0100836postcore_initcall(xenbus_init);
Jeremy Fitzhardinge4bac07c2007-07-17 18:37:06 -0700837
838MODULE_LICENSE("GPL");