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24ef1815 JB |
1 | /* -*- mode: c; c-basic-offset: 8; -*- |
2 | * vim: noexpandtab sw=8 ts=8 sts=0: | |
3 | * | |
4 | * stackglue.c | |
5 | * | |
6 | * Code which implements an OCFS2 specific interface to underlying | |
7 | * cluster stacks. | |
8 | * | |
9 | * Copyright (C) 2007 Oracle. All rights reserved. | |
10 | * | |
11 | * This program is free software; you can redistribute it and/or | |
12 | * modify it under the terms of the GNU General Public | |
13 | * License as published by the Free Software Foundation, version 2. | |
14 | * | |
15 | * This program is distributed in the hope that it will be useful, | |
16 | * but WITHOUT ANY WARRANTY; without even the implied warranty of | |
17 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU | |
18 | * General Public License for more details. | |
19 | */ | |
20 | ||
286eaa95 JB |
21 | #include <linux/list.h> |
22 | #include <linux/spinlock.h> | |
23 | #include <linux/module.h> | |
4670c46d | 24 | #include <linux/slab.h> |
6953b4c0 | 25 | #include <linux/kmod.h> |
74ae4e10 JB |
26 | #include <linux/fs.h> |
27 | #include <linux/kobject.h> | |
28 | #include <linux/sysfs.h> | |
3878f110 | 29 | #include <linux/sysctl.h> |
4670c46d | 30 | |
9c6c877c JB |
31 | #include "ocfs2_fs.h" |
32 | ||
286eaa95 | 33 | #include "stackglue.h" |
4670c46d | 34 | |
9c6c877c JB |
35 | #define OCFS2_STACK_PLUGIN_O2CB "o2cb" |
36 | #define OCFS2_STACK_PLUGIN_USER "user" | |
9f9a99f4 | 37 | #define OCFS2_MAX_HB_CTL_PATH 256 |
9c6c877c | 38 | |
286eaa95 JB |
39 | static struct ocfs2_locking_protocol *lproto; |
40 | static DEFINE_SPINLOCK(ocfs2_stack_lock); | |
41 | static LIST_HEAD(ocfs2_stack_list); | |
9c6c877c | 42 | static char cluster_stack_name[OCFS2_STACK_LABEL_LEN + 1]; |
9f9a99f4 | 43 | static char ocfs2_hb_ctl_path[OCFS2_MAX_HB_CTL_PATH] = "/sbin/ocfs2_hb_ctl"; |
19fdb624 | 44 | |
286eaa95 JB |
45 | /* |
46 | * The stack currently in use. If not null, active_stack->sp_count > 0, | |
47 | * the module is pinned, and the locking protocol cannot be changed. | |
48 | */ | |
49 | static struct ocfs2_stack_plugin *active_stack; | |
50 | ||
51 | static struct ocfs2_stack_plugin *ocfs2_stack_lookup(const char *name) | |
52 | { | |
53 | struct ocfs2_stack_plugin *p; | |
54 | ||
55 | assert_spin_locked(&ocfs2_stack_lock); | |
56 | ||
57 | list_for_each_entry(p, &ocfs2_stack_list, sp_list) { | |
58 | if (!strcmp(p->sp_name, name)) | |
59 | return p; | |
60 | } | |
61 | ||
62 | return NULL; | |
63 | } | |
64 | ||
9c6c877c JB |
65 | static int ocfs2_stack_driver_request(const char *stack_name, |
66 | const char *plugin_name) | |
286eaa95 JB |
67 | { |
68 | int rc; | |
69 | struct ocfs2_stack_plugin *p; | |
70 | ||
71 | spin_lock(&ocfs2_stack_lock); | |
72 | ||
9c6c877c JB |
73 | /* |
74 | * If the stack passed by the filesystem isn't the selected one, | |
75 | * we can't continue. | |
76 | */ | |
77 | if (strcmp(stack_name, cluster_stack_name)) { | |
78 | rc = -EBUSY; | |
79 | goto out; | |
80 | } | |
81 | ||
286eaa95 JB |
82 | if (active_stack) { |
83 | /* | |
84 | * If the active stack isn't the one we want, it cannot | |
85 | * be selected right now. | |
86 | */ | |
9c6c877c | 87 | if (!strcmp(active_stack->sp_name, plugin_name)) |
286eaa95 JB |
88 | rc = 0; |
89 | else | |
90 | rc = -EBUSY; | |
91 | goto out; | |
92 | } | |
93 | ||
9c6c877c | 94 | p = ocfs2_stack_lookup(plugin_name); |
286eaa95 JB |
95 | if (!p || !try_module_get(p->sp_owner)) { |
96 | rc = -ENOENT; | |
97 | goto out; | |
98 | } | |
99 | ||
100 | /* Ok, the stack is pinned */ | |
101 | p->sp_count++; | |
102 | active_stack = p; | |
103 | ||
104 | rc = 0; | |
105 | ||
106 | out: | |
107 | spin_unlock(&ocfs2_stack_lock); | |
108 | return rc; | |
109 | } | |
110 | ||
111 | /* | |
112 | * This function looks up the appropriate stack and makes it active. If | |
113 | * there is no stack, it tries to load it. It will fail if the stack still | |
114 | * cannot be found. It will also fail if a different stack is in use. | |
115 | */ | |
9c6c877c | 116 | static int ocfs2_stack_driver_get(const char *stack_name) |
286eaa95 JB |
117 | { |
118 | int rc; | |
9c6c877c JB |
119 | char *plugin_name = OCFS2_STACK_PLUGIN_O2CB; |
120 | ||
121 | /* | |
122 | * Classic stack does not pass in a stack name. This is | |
123 | * compatible with older tools as well. | |
124 | */ | |
125 | if (!stack_name || !*stack_name) | |
126 | stack_name = OCFS2_STACK_PLUGIN_O2CB; | |
127 | ||
128 | if (strlen(stack_name) != OCFS2_STACK_LABEL_LEN) { | |
129 | printk(KERN_ERR | |
130 | "ocfs2 passed an invalid cluster stack label: \"%s\"\n", | |
131 | stack_name); | |
132 | return -EINVAL; | |
133 | } | |
286eaa95 | 134 | |
9c6c877c JB |
135 | /* Anything that isn't the classic stack is a user stack */ |
136 | if (strcmp(stack_name, OCFS2_STACK_PLUGIN_O2CB)) | |
137 | plugin_name = OCFS2_STACK_PLUGIN_USER; | |
138 | ||
139 | rc = ocfs2_stack_driver_request(stack_name, plugin_name); | |
286eaa95 | 140 | if (rc == -ENOENT) { |
9c6c877c JB |
141 | request_module("ocfs2_stack_%s", plugin_name); |
142 | rc = ocfs2_stack_driver_request(stack_name, plugin_name); | |
286eaa95 JB |
143 | } |
144 | ||
145 | if (rc == -ENOENT) { | |
146 | printk(KERN_ERR | |
147 | "ocfs2: Cluster stack driver \"%s\" cannot be found\n", | |
9c6c877c | 148 | plugin_name); |
286eaa95 JB |
149 | } else if (rc == -EBUSY) { |
150 | printk(KERN_ERR | |
9c6c877c | 151 | "ocfs2: A different cluster stack is in use\n"); |
286eaa95 JB |
152 | } |
153 | ||
154 | return rc; | |
155 | } | |
24ef1815 | 156 | |
286eaa95 JB |
157 | static void ocfs2_stack_driver_put(void) |
158 | { | |
159 | spin_lock(&ocfs2_stack_lock); | |
160 | BUG_ON(active_stack == NULL); | |
161 | BUG_ON(active_stack->sp_count == 0); | |
162 | ||
163 | active_stack->sp_count--; | |
164 | if (!active_stack->sp_count) { | |
165 | module_put(active_stack->sp_owner); | |
166 | active_stack = NULL; | |
167 | } | |
168 | spin_unlock(&ocfs2_stack_lock); | |
169 | } | |
170 | ||
171 | int ocfs2_stack_glue_register(struct ocfs2_stack_plugin *plugin) | |
172 | { | |
173 | int rc; | |
174 | ||
175 | spin_lock(&ocfs2_stack_lock); | |
176 | if (!ocfs2_stack_lookup(plugin->sp_name)) { | |
177 | plugin->sp_count = 0; | |
178 | plugin->sp_proto = lproto; | |
179 | list_add(&plugin->sp_list, &ocfs2_stack_list); | |
180 | printk(KERN_INFO "ocfs2: Registered cluster interface %s\n", | |
181 | plugin->sp_name); | |
182 | rc = 0; | |
183 | } else { | |
184 | printk(KERN_ERR "ocfs2: Stack \"%s\" already registered\n", | |
185 | plugin->sp_name); | |
186 | rc = -EEXIST; | |
187 | } | |
188 | spin_unlock(&ocfs2_stack_lock); | |
189 | ||
190 | return rc; | |
191 | } | |
192 | EXPORT_SYMBOL_GPL(ocfs2_stack_glue_register); | |
193 | ||
194 | void ocfs2_stack_glue_unregister(struct ocfs2_stack_plugin *plugin) | |
195 | { | |
196 | struct ocfs2_stack_plugin *p; | |
197 | ||
198 | spin_lock(&ocfs2_stack_lock); | |
199 | p = ocfs2_stack_lookup(plugin->sp_name); | |
200 | if (p) { | |
201 | BUG_ON(p != plugin); | |
202 | BUG_ON(plugin == active_stack); | |
203 | BUG_ON(plugin->sp_count != 0); | |
204 | list_del_init(&plugin->sp_list); | |
205 | printk(KERN_INFO "ocfs2: Unregistered cluster interface %s\n", | |
206 | plugin->sp_name); | |
207 | } else { | |
208 | printk(KERN_ERR "Stack \"%s\" is not registered\n", | |
209 | plugin->sp_name); | |
210 | } | |
211 | spin_unlock(&ocfs2_stack_lock); | |
212 | } | |
213 | EXPORT_SYMBOL_GPL(ocfs2_stack_glue_unregister); | |
214 | ||
215 | void ocfs2_stack_glue_set_locking_protocol(struct ocfs2_locking_protocol *proto) | |
216 | { | |
217 | struct ocfs2_stack_plugin *p; | |
218 | ||
219 | BUG_ON(proto == NULL); | |
220 | ||
221 | spin_lock(&ocfs2_stack_lock); | |
222 | BUG_ON(active_stack != NULL); | |
223 | ||
224 | lproto = proto; | |
225 | list_for_each_entry(p, &ocfs2_stack_list, sp_list) { | |
226 | p->sp_proto = lproto; | |
227 | } | |
228 | ||
229 | spin_unlock(&ocfs2_stack_lock); | |
230 | } | |
231 | EXPORT_SYMBOL_GPL(ocfs2_stack_glue_set_locking_protocol); | |
7431cd7e | 232 | |
24ef1815 | 233 | |
cf4d8d75 DT |
234 | /* |
235 | * The ocfs2_dlm_lock() and ocfs2_dlm_unlock() functions take | |
236 | * "struct ocfs2_lock_res *astarg" instead of "void *astarg" because the | |
237 | * underlying stack plugins need to pilfer the lksb off of the lock_res. | |
238 | * If some other structure needs to be passed as an astarg, the plugins | |
239 | * will need to be given a different avenue to the lksb. | |
240 | */ | |
553aa7e4 JB |
241 | int ocfs2_dlm_lock(struct ocfs2_cluster_connection *conn, |
242 | int mode, | |
243 | union ocfs2_dlm_lksb *lksb, | |
244 | u32 flags, | |
245 | void *name, | |
246 | unsigned int namelen, | |
cf4d8d75 | 247 | struct ocfs2_lock_res *astarg) |
553aa7e4 | 248 | { |
286eaa95 | 249 | BUG_ON(lproto == NULL); |
bd3e7610 | 250 | |
286eaa95 JB |
251 | return active_stack->sp_ops->dlm_lock(conn, mode, lksb, flags, |
252 | name, namelen, astarg); | |
24ef1815 | 253 | } |
286eaa95 | 254 | EXPORT_SYMBOL_GPL(ocfs2_dlm_lock); |
24ef1815 | 255 | |
553aa7e4 JB |
256 | int ocfs2_dlm_unlock(struct ocfs2_cluster_connection *conn, |
257 | union ocfs2_dlm_lksb *lksb, | |
258 | u32 flags, | |
cf4d8d75 | 259 | struct ocfs2_lock_res *astarg) |
553aa7e4 | 260 | { |
286eaa95 | 261 | BUG_ON(lproto == NULL); |
553aa7e4 | 262 | |
286eaa95 | 263 | return active_stack->sp_ops->dlm_unlock(conn, lksb, flags, astarg); |
8f2c9c1b | 264 | } |
286eaa95 | 265 | EXPORT_SYMBOL_GPL(ocfs2_dlm_unlock); |
8f2c9c1b | 266 | |
553aa7e4 JB |
267 | int ocfs2_dlm_lock_status(union ocfs2_dlm_lksb *lksb) |
268 | { | |
286eaa95 | 269 | return active_stack->sp_ops->lock_status(lksb); |
553aa7e4 | 270 | } |
286eaa95 | 271 | EXPORT_SYMBOL_GPL(ocfs2_dlm_lock_status); |
553aa7e4 | 272 | |
8f2c9c1b JB |
273 | /* |
274 | * Why don't we cast to ocfs2_meta_lvb? The "clean" answer is that we | |
275 | * don't cast at the glue level. The real answer is that the header | |
276 | * ordering is nigh impossible. | |
277 | */ | |
553aa7e4 JB |
278 | void *ocfs2_dlm_lvb(union ocfs2_dlm_lksb *lksb) |
279 | { | |
286eaa95 | 280 | return active_stack->sp_ops->lock_lvb(lksb); |
cf0acdcd | 281 | } |
286eaa95 | 282 | EXPORT_SYMBOL_GPL(ocfs2_dlm_lvb); |
cf0acdcd | 283 | |
553aa7e4 JB |
284 | void ocfs2_dlm_dump_lksb(union ocfs2_dlm_lksb *lksb) |
285 | { | |
286eaa95 | 286 | active_stack->sp_ops->dump_lksb(lksb); |
553aa7e4 | 287 | } |
286eaa95 | 288 | EXPORT_SYMBOL_GPL(ocfs2_dlm_dump_lksb); |
553aa7e4 | 289 | |
9c6c877c JB |
290 | int ocfs2_cluster_connect(const char *stack_name, |
291 | const char *group, | |
4670c46d JB |
292 | int grouplen, |
293 | void (*recovery_handler)(int node_num, | |
294 | void *recovery_data), | |
295 | void *recovery_data, | |
296 | struct ocfs2_cluster_connection **conn) | |
297 | { | |
298 | int rc = 0; | |
299 | struct ocfs2_cluster_connection *new_conn; | |
4670c46d JB |
300 | |
301 | BUG_ON(group == NULL); | |
302 | BUG_ON(conn == NULL); | |
303 | BUG_ON(recovery_handler == NULL); | |
304 | ||
305 | if (grouplen > GROUP_NAME_MAX) { | |
306 | rc = -EINVAL; | |
307 | goto out; | |
308 | } | |
309 | ||
310 | new_conn = kzalloc(sizeof(struct ocfs2_cluster_connection), | |
311 | GFP_KERNEL); | |
312 | if (!new_conn) { | |
313 | rc = -ENOMEM; | |
314 | goto out; | |
315 | } | |
316 | ||
317 | memcpy(new_conn->cc_name, group, grouplen); | |
318 | new_conn->cc_namelen = grouplen; | |
319 | new_conn->cc_recovery_handler = recovery_handler; | |
320 | new_conn->cc_recovery_data = recovery_data; | |
321 | ||
322 | /* Start the new connection at our maximum compatibility level */ | |
286eaa95 JB |
323 | new_conn->cc_version = lproto->lp_max_version; |
324 | ||
325 | /* This will pin the stack driver if successful */ | |
9c6c877c | 326 | rc = ocfs2_stack_driver_get(stack_name); |
286eaa95 JB |
327 | if (rc) |
328 | goto out_free; | |
4670c46d | 329 | |
286eaa95 | 330 | rc = active_stack->sp_ops->connect(new_conn); |
553aa7e4 | 331 | if (rc) { |
286eaa95 | 332 | ocfs2_stack_driver_put(); |
4670c46d JB |
333 | goto out_free; |
334 | } | |
335 | ||
4670c46d JB |
336 | *conn = new_conn; |
337 | ||
338 | out_free: | |
553aa7e4 | 339 | if (rc) |
4670c46d | 340 | kfree(new_conn); |
4670c46d JB |
341 | |
342 | out: | |
343 | return rc; | |
344 | } | |
286eaa95 | 345 | EXPORT_SYMBOL_GPL(ocfs2_cluster_connect); |
4670c46d | 346 | |
286eaa95 JB |
347 | /* If hangup_pending is 0, the stack driver will be dropped */ |
348 | int ocfs2_cluster_disconnect(struct ocfs2_cluster_connection *conn, | |
349 | int hangup_pending) | |
553aa7e4 JB |
350 | { |
351 | int ret; | |
352 | ||
353 | BUG_ON(conn == NULL); | |
354 | ||
286eaa95 | 355 | ret = active_stack->sp_ops->disconnect(conn, hangup_pending); |
553aa7e4 JB |
356 | |
357 | /* XXX Should we free it anyway? */ | |
286eaa95 | 358 | if (!ret) { |
553aa7e4 | 359 | kfree(conn); |
286eaa95 JB |
360 | if (!hangup_pending) |
361 | ocfs2_stack_driver_put(); | |
362 | } | |
553aa7e4 JB |
363 | |
364 | return ret; | |
365 | } | |
286eaa95 | 366 | EXPORT_SYMBOL_GPL(ocfs2_cluster_disconnect); |
553aa7e4 | 367 | |
9f9a99f4 JB |
368 | /* |
369 | * Leave the group for this filesystem. This is executed by a userspace | |
370 | * program (stored in ocfs2_hb_ctl_path). | |
371 | */ | |
372 | static void ocfs2_leave_group(const char *group) | |
373 | { | |
374 | int ret; | |
375 | char *argv[5], *envp[3]; | |
376 | ||
377 | argv[0] = ocfs2_hb_ctl_path; | |
378 | argv[1] = "-K"; | |
379 | argv[2] = "-u"; | |
380 | argv[3] = (char *)group; | |
381 | argv[4] = NULL; | |
382 | ||
383 | /* minimal command environment taken from cpu_run_sbin_hotplug */ | |
384 | envp[0] = "HOME=/"; | |
385 | envp[1] = "PATH=/sbin:/bin:/usr/sbin:/usr/bin"; | |
386 | envp[2] = NULL; | |
387 | ||
388 | ret = call_usermodehelper(argv[0], argv, envp, UMH_WAIT_PROC); | |
389 | if (ret < 0) { | |
390 | printk(KERN_ERR | |
391 | "ocfs2: Error %d running user helper " | |
392 | "\"%s %s %s %s\"\n", | |
393 | ret, argv[0], argv[1], argv[2], argv[3]); | |
394 | } | |
395 | } | |
396 | ||
397 | /* | |
398 | * Hangup is a required post-umount. ocfs2-tools software expects the | |
399 | * filesystem to call "ocfs2_hb_ctl" during unmount. This happens | |
400 | * regardless of whether the DLM got started, so we can't do it | |
401 | * in ocfs2_cluster_disconnect(). The ocfs2_leave_group() function does | |
402 | * the actual work. | |
403 | */ | |
6953b4c0 JB |
404 | void ocfs2_cluster_hangup(const char *group, int grouplen) |
405 | { | |
406 | BUG_ON(group == NULL); | |
407 | BUG_ON(group[grouplen] != '\0'); | |
408 | ||
cf4d8d75 DT |
409 | if (active_stack->sp_ops->hangup) |
410 | active_stack->sp_ops->hangup(group, grouplen); | |
286eaa95 | 411 | |
9f9a99f4 JB |
412 | ocfs2_leave_group(group); |
413 | ||
286eaa95 JB |
414 | /* cluster_disconnect() was called with hangup_pending==1 */ |
415 | ocfs2_stack_driver_put(); | |
19fdb624 | 416 | } |
286eaa95 | 417 | EXPORT_SYMBOL_GPL(ocfs2_cluster_hangup); |
19fdb624 | 418 | |
553aa7e4 JB |
419 | int ocfs2_cluster_this_node(unsigned int *node) |
420 | { | |
286eaa95 | 421 | return active_stack->sp_ops->this_node(node); |
553aa7e4 | 422 | } |
286eaa95 | 423 | EXPORT_SYMBOL_GPL(ocfs2_cluster_this_node); |
553aa7e4 | 424 | |
286eaa95 | 425 | |
74ae4e10 JB |
426 | /* |
427 | * Sysfs bits | |
428 | */ | |
429 | ||
430 | static ssize_t ocfs2_max_locking_protocol_show(struct kobject *kobj, | |
431 | struct kobj_attribute *attr, | |
432 | char *buf) | |
433 | { | |
434 | ssize_t ret = 0; | |
435 | ||
436 | spin_lock(&ocfs2_stack_lock); | |
437 | if (lproto) | |
438 | ret = snprintf(buf, PAGE_SIZE, "%u.%u\n", | |
439 | lproto->lp_max_version.pv_major, | |
440 | lproto->lp_max_version.pv_minor); | |
441 | spin_unlock(&ocfs2_stack_lock); | |
442 | ||
443 | return ret; | |
444 | } | |
445 | ||
446 | static struct kobj_attribute ocfs2_attr_max_locking_protocol = | |
447 | __ATTR(max_locking_protocol, S_IFREG | S_IRUGO, | |
448 | ocfs2_max_locking_protocol_show, NULL); | |
449 | ||
450 | static ssize_t ocfs2_loaded_cluster_plugins_show(struct kobject *kobj, | |
451 | struct kobj_attribute *attr, | |
452 | char *buf) | |
24ef1815 | 453 | { |
74ae4e10 JB |
454 | ssize_t ret = 0, total = 0, remain = PAGE_SIZE; |
455 | struct ocfs2_stack_plugin *p; | |
456 | ||
457 | spin_lock(&ocfs2_stack_lock); | |
458 | list_for_each_entry(p, &ocfs2_stack_list, sp_list) { | |
459 | ret = snprintf(buf, remain, "%s\n", | |
460 | p->sp_name); | |
461 | if (ret < 0) { | |
462 | total = ret; | |
463 | break; | |
464 | } | |
465 | if (ret == remain) { | |
466 | /* snprintf() didn't fit */ | |
467 | total = -E2BIG; | |
468 | break; | |
469 | } | |
470 | total += ret; | |
471 | remain -= ret; | |
472 | } | |
473 | spin_unlock(&ocfs2_stack_lock); | |
474 | ||
475 | return total; | |
476 | } | |
477 | ||
478 | static struct kobj_attribute ocfs2_attr_loaded_cluster_plugins = | |
479 | __ATTR(loaded_cluster_plugins, S_IFREG | S_IRUGO, | |
480 | ocfs2_loaded_cluster_plugins_show, NULL); | |
481 | ||
482 | static ssize_t ocfs2_active_cluster_plugin_show(struct kobject *kobj, | |
483 | struct kobj_attribute *attr, | |
484 | char *buf) | |
485 | { | |
486 | ssize_t ret = 0; | |
487 | ||
488 | spin_lock(&ocfs2_stack_lock); | |
489 | if (active_stack) { | |
490 | ret = snprintf(buf, PAGE_SIZE, "%s\n", | |
491 | active_stack->sp_name); | |
492 | if (ret == PAGE_SIZE) | |
493 | ret = -E2BIG; | |
494 | } | |
495 | spin_unlock(&ocfs2_stack_lock); | |
496 | ||
497 | return ret; | |
498 | } | |
499 | ||
500 | static struct kobj_attribute ocfs2_attr_active_cluster_plugin = | |
501 | __ATTR(active_cluster_plugin, S_IFREG | S_IRUGO, | |
502 | ocfs2_active_cluster_plugin_show, NULL); | |
503 | ||
9c6c877c JB |
504 | static ssize_t ocfs2_cluster_stack_show(struct kobject *kobj, |
505 | struct kobj_attribute *attr, | |
506 | char *buf) | |
507 | { | |
508 | ssize_t ret; | |
509 | spin_lock(&ocfs2_stack_lock); | |
510 | ret = snprintf(buf, PAGE_SIZE, "%s\n", cluster_stack_name); | |
511 | spin_unlock(&ocfs2_stack_lock); | |
512 | ||
513 | return ret; | |
514 | } | |
515 | ||
516 | static ssize_t ocfs2_cluster_stack_store(struct kobject *kobj, | |
517 | struct kobj_attribute *attr, | |
518 | const char *buf, size_t count) | |
519 | { | |
520 | size_t len = count; | |
521 | ssize_t ret; | |
522 | ||
523 | if (len == 0) | |
524 | return len; | |
525 | ||
526 | if (buf[len - 1] == '\n') | |
527 | len--; | |
528 | ||
529 | if ((len != OCFS2_STACK_LABEL_LEN) || | |
530 | (strnlen(buf, len) != len)) | |
531 | return -EINVAL; | |
532 | ||
533 | spin_lock(&ocfs2_stack_lock); | |
534 | if (active_stack) { | |
535 | if (!strncmp(buf, cluster_stack_name, len)) | |
536 | ret = count; | |
537 | else | |
538 | ret = -EBUSY; | |
539 | } else { | |
540 | memcpy(cluster_stack_name, buf, len); | |
541 | ret = count; | |
542 | } | |
543 | spin_unlock(&ocfs2_stack_lock); | |
544 | ||
545 | return ret; | |
546 | } | |
547 | ||
548 | ||
549 | static struct kobj_attribute ocfs2_attr_cluster_stack = | |
550 | __ATTR(cluster_stack, S_IFREG | S_IRUGO | S_IWUSR, | |
551 | ocfs2_cluster_stack_show, | |
552 | ocfs2_cluster_stack_store); | |
553 | ||
74ae4e10 JB |
554 | static struct attribute *ocfs2_attrs[] = { |
555 | &ocfs2_attr_max_locking_protocol.attr, | |
556 | &ocfs2_attr_loaded_cluster_plugins.attr, | |
557 | &ocfs2_attr_active_cluster_plugin.attr, | |
9c6c877c | 558 | &ocfs2_attr_cluster_stack.attr, |
74ae4e10 JB |
559 | NULL, |
560 | }; | |
561 | ||
562 | static struct attribute_group ocfs2_attr_group = { | |
563 | .attrs = ocfs2_attrs, | |
564 | }; | |
565 | ||
566 | static struct kset *ocfs2_kset; | |
567 | ||
568 | static void ocfs2_sysfs_exit(void) | |
569 | { | |
570 | kset_unregister(ocfs2_kset); | |
571 | } | |
572 | ||
573 | static int ocfs2_sysfs_init(void) | |
574 | { | |
575 | int ret; | |
576 | ||
577 | ocfs2_kset = kset_create_and_add("ocfs2", NULL, fs_kobj); | |
578 | if (!ocfs2_kset) | |
579 | return -ENOMEM; | |
580 | ||
581 | ret = sysfs_create_group(&ocfs2_kset->kobj, &ocfs2_attr_group); | |
582 | if (ret) | |
583 | goto error; | |
584 | ||
286eaa95 | 585 | return 0; |
74ae4e10 JB |
586 | |
587 | error: | |
588 | kset_unregister(ocfs2_kset); | |
589 | return ret; | |
590 | } | |
591 | ||
3878f110 JB |
592 | /* |
593 | * Sysctl bits | |
594 | * | |
595 | * The sysctl lives at /proc/sys/fs/ocfs2/nm/hb_ctl_path. The 'nm' doesn't | |
596 | * make as much sense in a multiple cluster stack world, but it's safer | |
597 | * and easier to preserve the name. | |
598 | */ | |
599 | ||
600 | #define FS_OCFS2_NM 1 | |
601 | ||
3878f110 JB |
602 | static ctl_table ocfs2_nm_table[] = { |
603 | { | |
604 | .ctl_name = 1, | |
605 | .procname = "hb_ctl_path", | |
606 | .data = ocfs2_hb_ctl_path, | |
607 | .maxlen = OCFS2_MAX_HB_CTL_PATH, | |
608 | .mode = 0644, | |
609 | .proc_handler = &proc_dostring, | |
610 | .strategy = &sysctl_string, | |
611 | }, | |
612 | { .ctl_name = 0 } | |
613 | }; | |
614 | ||
615 | static ctl_table ocfs2_mod_table[] = { | |
616 | { | |
617 | .ctl_name = FS_OCFS2_NM, | |
618 | .procname = "nm", | |
619 | .data = NULL, | |
620 | .maxlen = 0, | |
621 | .mode = 0555, | |
622 | .child = ocfs2_nm_table | |
623 | }, | |
624 | { .ctl_name = 0} | |
625 | }; | |
626 | ||
627 | static ctl_table ocfs2_kern_table[] = { | |
628 | { | |
629 | .ctl_name = FS_OCFS2, | |
630 | .procname = "ocfs2", | |
631 | .data = NULL, | |
632 | .maxlen = 0, | |
633 | .mode = 0555, | |
634 | .child = ocfs2_mod_table | |
635 | }, | |
636 | { .ctl_name = 0} | |
637 | }; | |
638 | ||
639 | static ctl_table ocfs2_root_table[] = { | |
640 | { | |
641 | .ctl_name = CTL_FS, | |
642 | .procname = "fs", | |
643 | .data = NULL, | |
644 | .maxlen = 0, | |
645 | .mode = 0555, | |
646 | .child = ocfs2_kern_table | |
647 | }, | |
648 | { .ctl_name = 0 } | |
649 | }; | |
650 | ||
651 | static struct ctl_table_header *ocfs2_table_header = NULL; | |
652 | ||
3878f110 JB |
653 | |
654 | /* | |
655 | * Initialization | |
656 | */ | |
657 | ||
74ae4e10 JB |
658 | static int __init ocfs2_stack_glue_init(void) |
659 | { | |
9c6c877c JB |
660 | strcpy(cluster_stack_name, OCFS2_STACK_PLUGIN_O2CB); |
661 | ||
3878f110 JB |
662 | ocfs2_table_header = register_sysctl_table(ocfs2_root_table); |
663 | if (!ocfs2_table_header) { | |
664 | printk(KERN_ERR | |
665 | "ocfs2 stack glue: unable to register sysctl\n"); | |
666 | return -ENOMEM; /* or something. */ | |
667 | } | |
668 | ||
74ae4e10 | 669 | return ocfs2_sysfs_init(); |
286eaa95 | 670 | } |
24ef1815 | 671 | |
286eaa95 JB |
672 | static void __exit ocfs2_stack_glue_exit(void) |
673 | { | |
674 | lproto = NULL; | |
74ae4e10 | 675 | ocfs2_sysfs_exit(); |
3878f110 JB |
676 | if (ocfs2_table_header) |
677 | unregister_sysctl_table(ocfs2_table_header); | |
24ef1815 JB |
678 | } |
679 | ||
286eaa95 JB |
680 | MODULE_AUTHOR("Oracle"); |
681 | MODULE_DESCRIPTION("ocfs2 cluter stack glue layer"); | |
682 | MODULE_LICENSE("GPL"); | |
683 | module_init(ocfs2_stack_glue_init); | |
684 | module_exit(ocfs2_stack_glue_exit); |