1 | // SPDX-License-Identifier: GPL-2.0-only |
2 | /* |
3 | * stackglue.c |
4 | * |
5 | * Code which implements an OCFS2 specific interface to underlying |
6 | * cluster stacks. |
7 | * |
8 | * Copyright (C) 2007, 2009 Oracle. All rights reserved. |
9 | */ |
10 | |
11 | #include <linux/list.h> |
12 | #include <linux/spinlock.h> |
13 | #include <linux/module.h> |
14 | #include <linux/slab.h> |
15 | #include <linux/kmod.h> |
16 | #include <linux/fs.h> |
17 | #include <linux/kobject.h> |
18 | #include <linux/sysfs.h> |
19 | #include <linux/sysctl.h> |
20 | |
21 | #include "ocfs2_fs.h" |
22 | |
23 | #include "stackglue.h" |
24 | |
25 | #define OCFS2_STACK_PLUGIN_O2CB "o2cb" |
26 | #define OCFS2_STACK_PLUGIN_USER "user" |
27 | #define OCFS2_MAX_HB_CTL_PATH 256 |
28 | |
29 | static struct ocfs2_protocol_version locking_max_version; |
30 | static DEFINE_SPINLOCK(ocfs2_stack_lock); |
31 | static LIST_HEAD(ocfs2_stack_list); |
32 | static char cluster_stack_name[OCFS2_STACK_LABEL_LEN + 1]; |
33 | static char ocfs2_hb_ctl_path[OCFS2_MAX_HB_CTL_PATH] = "/sbin/ocfs2_hb_ctl" ; |
34 | |
35 | /* |
36 | * The stack currently in use. If not null, active_stack->sp_count > 0, |
37 | * the module is pinned, and the locking protocol cannot be changed. |
38 | */ |
39 | static struct ocfs2_stack_plugin *active_stack; |
40 | |
41 | static struct ocfs2_stack_plugin *ocfs2_stack_lookup(const char *name) |
42 | { |
43 | struct ocfs2_stack_plugin *p; |
44 | |
45 | assert_spin_locked(&ocfs2_stack_lock); |
46 | |
47 | list_for_each_entry(p, &ocfs2_stack_list, sp_list) { |
48 | if (!strcmp(p->sp_name, name)) |
49 | return p; |
50 | } |
51 | |
52 | return NULL; |
53 | } |
54 | |
55 | static int ocfs2_stack_driver_request(const char *stack_name, |
56 | const char *plugin_name) |
57 | { |
58 | int rc; |
59 | struct ocfs2_stack_plugin *p; |
60 | |
61 | spin_lock(lock: &ocfs2_stack_lock); |
62 | |
63 | /* |
64 | * If the stack passed by the filesystem isn't the selected one, |
65 | * we can't continue. |
66 | */ |
67 | if (strcmp(stack_name, cluster_stack_name)) { |
68 | rc = -EBUSY; |
69 | goto out; |
70 | } |
71 | |
72 | if (active_stack) { |
73 | /* |
74 | * If the active stack isn't the one we want, it cannot |
75 | * be selected right now. |
76 | */ |
77 | if (!strcmp(active_stack->sp_name, plugin_name)) |
78 | rc = 0; |
79 | else |
80 | rc = -EBUSY; |
81 | goto out; |
82 | } |
83 | |
84 | p = ocfs2_stack_lookup(name: plugin_name); |
85 | if (!p || !try_module_get(module: p->sp_owner)) { |
86 | rc = -ENOENT; |
87 | goto out; |
88 | } |
89 | |
90 | active_stack = p; |
91 | rc = 0; |
92 | |
93 | out: |
94 | /* If we found it, pin it */ |
95 | if (!rc) |
96 | active_stack->sp_count++; |
97 | |
98 | spin_unlock(lock: &ocfs2_stack_lock); |
99 | return rc; |
100 | } |
101 | |
102 | /* |
103 | * This function looks up the appropriate stack and makes it active. If |
104 | * there is no stack, it tries to load it. It will fail if the stack still |
105 | * cannot be found. It will also fail if a different stack is in use. |
106 | */ |
107 | static int ocfs2_stack_driver_get(const char *stack_name) |
108 | { |
109 | int rc; |
110 | char *plugin_name = OCFS2_STACK_PLUGIN_O2CB; |
111 | |
112 | /* |
113 | * Classic stack does not pass in a stack name. This is |
114 | * compatible with older tools as well. |
115 | */ |
116 | if (!stack_name || !*stack_name) |
117 | stack_name = OCFS2_STACK_PLUGIN_O2CB; |
118 | |
119 | if (strlen(stack_name) != OCFS2_STACK_LABEL_LEN) { |
120 | printk(KERN_ERR |
121 | "ocfs2 passed an invalid cluster stack label: \"%s\"\n" , |
122 | stack_name); |
123 | return -EINVAL; |
124 | } |
125 | |
126 | /* Anything that isn't the classic stack is a user stack */ |
127 | if (strcmp(stack_name, OCFS2_STACK_PLUGIN_O2CB)) |
128 | plugin_name = OCFS2_STACK_PLUGIN_USER; |
129 | |
130 | rc = ocfs2_stack_driver_request(stack_name, plugin_name); |
131 | if (rc == -ENOENT) { |
132 | request_module("ocfs2_stack_%s" , plugin_name); |
133 | rc = ocfs2_stack_driver_request(stack_name, plugin_name); |
134 | } |
135 | |
136 | if (rc == -ENOENT) { |
137 | printk(KERN_ERR |
138 | "ocfs2: Cluster stack driver \"%s\" cannot be found\n" , |
139 | plugin_name); |
140 | } else if (rc == -EBUSY) { |
141 | printk(KERN_ERR |
142 | "ocfs2: A different cluster stack is in use\n" ); |
143 | } |
144 | |
145 | return rc; |
146 | } |
147 | |
148 | static void ocfs2_stack_driver_put(void) |
149 | { |
150 | spin_lock(lock: &ocfs2_stack_lock); |
151 | BUG_ON(active_stack == NULL); |
152 | BUG_ON(active_stack->sp_count == 0); |
153 | |
154 | active_stack->sp_count--; |
155 | if (!active_stack->sp_count) { |
156 | module_put(module: active_stack->sp_owner); |
157 | active_stack = NULL; |
158 | } |
159 | spin_unlock(lock: &ocfs2_stack_lock); |
160 | } |
161 | |
162 | int ocfs2_stack_glue_register(struct ocfs2_stack_plugin *plugin) |
163 | { |
164 | int rc; |
165 | |
166 | spin_lock(lock: &ocfs2_stack_lock); |
167 | if (!ocfs2_stack_lookup(name: plugin->sp_name)) { |
168 | plugin->sp_count = 0; |
169 | plugin->sp_max_proto = locking_max_version; |
170 | list_add(new: &plugin->sp_list, head: &ocfs2_stack_list); |
171 | printk(KERN_INFO "ocfs2: Registered cluster interface %s\n" , |
172 | plugin->sp_name); |
173 | rc = 0; |
174 | } else { |
175 | printk(KERN_ERR "ocfs2: Stack \"%s\" already registered\n" , |
176 | plugin->sp_name); |
177 | rc = -EEXIST; |
178 | } |
179 | spin_unlock(lock: &ocfs2_stack_lock); |
180 | |
181 | return rc; |
182 | } |
183 | EXPORT_SYMBOL_GPL(ocfs2_stack_glue_register); |
184 | |
185 | void ocfs2_stack_glue_unregister(struct ocfs2_stack_plugin *plugin) |
186 | { |
187 | struct ocfs2_stack_plugin *p; |
188 | |
189 | spin_lock(lock: &ocfs2_stack_lock); |
190 | p = ocfs2_stack_lookup(name: plugin->sp_name); |
191 | if (p) { |
192 | BUG_ON(p != plugin); |
193 | BUG_ON(plugin == active_stack); |
194 | BUG_ON(plugin->sp_count != 0); |
195 | list_del_init(entry: &plugin->sp_list); |
196 | printk(KERN_INFO "ocfs2: Unregistered cluster interface %s\n" , |
197 | plugin->sp_name); |
198 | } else { |
199 | printk(KERN_ERR "Stack \"%s\" is not registered\n" , |
200 | plugin->sp_name); |
201 | } |
202 | spin_unlock(lock: &ocfs2_stack_lock); |
203 | } |
204 | EXPORT_SYMBOL_GPL(ocfs2_stack_glue_unregister); |
205 | |
206 | void ocfs2_stack_glue_set_max_proto_version(struct ocfs2_protocol_version *max_proto) |
207 | { |
208 | struct ocfs2_stack_plugin *p; |
209 | |
210 | spin_lock(lock: &ocfs2_stack_lock); |
211 | if (memcmp(p: max_proto, q: &locking_max_version, |
212 | size: sizeof(struct ocfs2_protocol_version))) { |
213 | BUG_ON(locking_max_version.pv_major != 0); |
214 | |
215 | locking_max_version = *max_proto; |
216 | list_for_each_entry(p, &ocfs2_stack_list, sp_list) { |
217 | p->sp_max_proto = locking_max_version; |
218 | } |
219 | } |
220 | spin_unlock(lock: &ocfs2_stack_lock); |
221 | } |
222 | EXPORT_SYMBOL_GPL(ocfs2_stack_glue_set_max_proto_version); |
223 | |
224 | |
225 | /* |
226 | * The ocfs2_dlm_lock() and ocfs2_dlm_unlock() functions take no argument |
227 | * for the ast and bast functions. They will pass the lksb to the ast |
228 | * and bast. The caller can wrap the lksb with their own structure to |
229 | * get more information. |
230 | */ |
231 | int ocfs2_dlm_lock(struct ocfs2_cluster_connection *conn, |
232 | int mode, |
233 | struct ocfs2_dlm_lksb *lksb, |
234 | u32 flags, |
235 | void *name, |
236 | unsigned int namelen) |
237 | { |
238 | if (!lksb->lksb_conn) |
239 | lksb->lksb_conn = conn; |
240 | else |
241 | BUG_ON(lksb->lksb_conn != conn); |
242 | return active_stack->sp_ops->dlm_lock(conn, mode, lksb, flags, |
243 | name, namelen); |
244 | } |
245 | EXPORT_SYMBOL_GPL(ocfs2_dlm_lock); |
246 | |
247 | int ocfs2_dlm_unlock(struct ocfs2_cluster_connection *conn, |
248 | struct ocfs2_dlm_lksb *lksb, |
249 | u32 flags) |
250 | { |
251 | BUG_ON(lksb->lksb_conn == NULL); |
252 | |
253 | return active_stack->sp_ops->dlm_unlock(conn, lksb, flags); |
254 | } |
255 | EXPORT_SYMBOL_GPL(ocfs2_dlm_unlock); |
256 | |
257 | int ocfs2_dlm_lock_status(struct ocfs2_dlm_lksb *lksb) |
258 | { |
259 | return active_stack->sp_ops->lock_status(lksb); |
260 | } |
261 | EXPORT_SYMBOL_GPL(ocfs2_dlm_lock_status); |
262 | |
263 | int ocfs2_dlm_lvb_valid(struct ocfs2_dlm_lksb *lksb) |
264 | { |
265 | return active_stack->sp_ops->lvb_valid(lksb); |
266 | } |
267 | EXPORT_SYMBOL_GPL(ocfs2_dlm_lvb_valid); |
268 | |
269 | void *ocfs2_dlm_lvb(struct ocfs2_dlm_lksb *lksb) |
270 | { |
271 | return active_stack->sp_ops->lock_lvb(lksb); |
272 | } |
273 | EXPORT_SYMBOL_GPL(ocfs2_dlm_lvb); |
274 | |
275 | void ocfs2_dlm_dump_lksb(struct ocfs2_dlm_lksb *lksb) |
276 | { |
277 | active_stack->sp_ops->dump_lksb(lksb); |
278 | } |
279 | EXPORT_SYMBOL_GPL(ocfs2_dlm_dump_lksb); |
280 | |
281 | int ocfs2_stack_supports_plocks(void) |
282 | { |
283 | return active_stack && active_stack->sp_ops->plock; |
284 | } |
285 | EXPORT_SYMBOL_GPL(ocfs2_stack_supports_plocks); |
286 | |
287 | /* |
288 | * ocfs2_plock() can only be safely called if |
289 | * ocfs2_stack_supports_plocks() returned true |
290 | */ |
291 | int ocfs2_plock(struct ocfs2_cluster_connection *conn, u64 ino, |
292 | struct file *file, int cmd, struct file_lock *fl) |
293 | { |
294 | WARN_ON_ONCE(active_stack->sp_ops->plock == NULL); |
295 | if (active_stack->sp_ops->plock) |
296 | return active_stack->sp_ops->plock(conn, ino, file, cmd, fl); |
297 | return -EOPNOTSUPP; |
298 | } |
299 | EXPORT_SYMBOL_GPL(ocfs2_plock); |
300 | |
301 | int ocfs2_cluster_connect(const char *stack_name, |
302 | const char *cluster_name, |
303 | int cluster_name_len, |
304 | const char *group, |
305 | int grouplen, |
306 | struct ocfs2_locking_protocol *lproto, |
307 | void (*recovery_handler)(int node_num, |
308 | void *recovery_data), |
309 | void *recovery_data, |
310 | struct ocfs2_cluster_connection **conn) |
311 | { |
312 | int rc = 0; |
313 | struct ocfs2_cluster_connection *new_conn; |
314 | |
315 | BUG_ON(group == NULL); |
316 | BUG_ON(conn == NULL); |
317 | BUG_ON(recovery_handler == NULL); |
318 | |
319 | if (grouplen > GROUP_NAME_MAX) { |
320 | rc = -EINVAL; |
321 | goto out; |
322 | } |
323 | |
324 | if (memcmp(p: &lproto->lp_max_version, q: &locking_max_version, |
325 | size: sizeof(struct ocfs2_protocol_version))) { |
326 | rc = -EINVAL; |
327 | goto out; |
328 | } |
329 | |
330 | new_conn = kzalloc(size: sizeof(struct ocfs2_cluster_connection), |
331 | GFP_KERNEL); |
332 | if (!new_conn) { |
333 | rc = -ENOMEM; |
334 | goto out; |
335 | } |
336 | |
337 | strscpy(p: new_conn->cc_name, q: group, GROUP_NAME_MAX + 1); |
338 | new_conn->cc_namelen = grouplen; |
339 | if (cluster_name_len) |
340 | strscpy(p: new_conn->cc_cluster_name, q: cluster_name, |
341 | CLUSTER_NAME_MAX + 1); |
342 | new_conn->cc_cluster_name_len = cluster_name_len; |
343 | new_conn->cc_recovery_handler = recovery_handler; |
344 | new_conn->cc_recovery_data = recovery_data; |
345 | |
346 | new_conn->cc_proto = lproto; |
347 | /* Start the new connection at our maximum compatibility level */ |
348 | new_conn->cc_version = lproto->lp_max_version; |
349 | |
350 | /* This will pin the stack driver if successful */ |
351 | rc = ocfs2_stack_driver_get(stack_name); |
352 | if (rc) |
353 | goto out_free; |
354 | |
355 | rc = active_stack->sp_ops->connect(new_conn); |
356 | if (rc) { |
357 | ocfs2_stack_driver_put(); |
358 | goto out_free; |
359 | } |
360 | |
361 | *conn = new_conn; |
362 | |
363 | out_free: |
364 | if (rc) |
365 | kfree(objp: new_conn); |
366 | |
367 | out: |
368 | return rc; |
369 | } |
370 | EXPORT_SYMBOL_GPL(ocfs2_cluster_connect); |
371 | |
372 | /* The caller will ensure all nodes have the same cluster stack */ |
373 | int ocfs2_cluster_connect_agnostic(const char *group, |
374 | int grouplen, |
375 | struct ocfs2_locking_protocol *lproto, |
376 | void (*recovery_handler)(int node_num, |
377 | void *recovery_data), |
378 | void *recovery_data, |
379 | struct ocfs2_cluster_connection **conn) |
380 | { |
381 | char *stack_name = NULL; |
382 | |
383 | if (cluster_stack_name[0]) |
384 | stack_name = cluster_stack_name; |
385 | return ocfs2_cluster_connect(stack_name, NULL, 0, group, grouplen, |
386 | lproto, recovery_handler, recovery_data, |
387 | conn); |
388 | } |
389 | EXPORT_SYMBOL_GPL(ocfs2_cluster_connect_agnostic); |
390 | |
391 | /* If hangup_pending is 0, the stack driver will be dropped */ |
392 | int ocfs2_cluster_disconnect(struct ocfs2_cluster_connection *conn, |
393 | int hangup_pending) |
394 | { |
395 | int ret; |
396 | |
397 | BUG_ON(conn == NULL); |
398 | |
399 | ret = active_stack->sp_ops->disconnect(conn); |
400 | |
401 | /* XXX Should we free it anyway? */ |
402 | if (!ret) { |
403 | kfree(objp: conn); |
404 | if (!hangup_pending) |
405 | ocfs2_stack_driver_put(); |
406 | } |
407 | |
408 | return ret; |
409 | } |
410 | EXPORT_SYMBOL_GPL(ocfs2_cluster_disconnect); |
411 | |
412 | /* |
413 | * Leave the group for this filesystem. This is executed by a userspace |
414 | * program (stored in ocfs2_hb_ctl_path). |
415 | */ |
416 | static void ocfs2_leave_group(const char *group) |
417 | { |
418 | int ret; |
419 | char *argv[5], *envp[3]; |
420 | |
421 | argv[0] = ocfs2_hb_ctl_path; |
422 | argv[1] = "-K" ; |
423 | argv[2] = "-u" ; |
424 | argv[3] = (char *)group; |
425 | argv[4] = NULL; |
426 | |
427 | /* minimal command environment taken from cpu_run_sbin_hotplug */ |
428 | envp[0] = "HOME=/" ; |
429 | envp[1] = "PATH=/sbin:/bin:/usr/sbin:/usr/bin" ; |
430 | envp[2] = NULL; |
431 | |
432 | ret = call_usermodehelper(path: argv[0], argv, envp, UMH_WAIT_PROC); |
433 | if (ret < 0) { |
434 | printk(KERN_ERR |
435 | "ocfs2: Error %d running user helper " |
436 | "\"%s %s %s %s\"\n" , |
437 | ret, argv[0], argv[1], argv[2], argv[3]); |
438 | } |
439 | } |
440 | |
441 | /* |
442 | * Hangup is a required post-umount. ocfs2-tools software expects the |
443 | * filesystem to call "ocfs2_hb_ctl" during unmount. This happens |
444 | * regardless of whether the DLM got started, so we can't do it |
445 | * in ocfs2_cluster_disconnect(). The ocfs2_leave_group() function does |
446 | * the actual work. |
447 | */ |
448 | void ocfs2_cluster_hangup(const char *group, int grouplen) |
449 | { |
450 | BUG_ON(group == NULL); |
451 | BUG_ON(group[grouplen] != '\0'); |
452 | |
453 | ocfs2_leave_group(group); |
454 | |
455 | /* cluster_disconnect() was called with hangup_pending==1 */ |
456 | ocfs2_stack_driver_put(); |
457 | } |
458 | EXPORT_SYMBOL_GPL(ocfs2_cluster_hangup); |
459 | |
460 | int ocfs2_cluster_this_node(struct ocfs2_cluster_connection *conn, |
461 | unsigned int *node) |
462 | { |
463 | return active_stack->sp_ops->this_node(conn, node); |
464 | } |
465 | EXPORT_SYMBOL_GPL(ocfs2_cluster_this_node); |
466 | |
467 | |
468 | /* |
469 | * Sysfs bits |
470 | */ |
471 | |
472 | static ssize_t ocfs2_max_locking_protocol_show(struct kobject *kobj, |
473 | struct kobj_attribute *attr, |
474 | char *buf) |
475 | { |
476 | ssize_t ret = 0; |
477 | |
478 | spin_lock(lock: &ocfs2_stack_lock); |
479 | if (locking_max_version.pv_major) |
480 | ret = snprintf(buf, PAGE_SIZE, fmt: "%u.%u\n" , |
481 | locking_max_version.pv_major, |
482 | locking_max_version.pv_minor); |
483 | spin_unlock(lock: &ocfs2_stack_lock); |
484 | |
485 | return ret; |
486 | } |
487 | |
488 | static struct kobj_attribute ocfs2_attr_max_locking_protocol = |
489 | __ATTR(max_locking_protocol, S_IRUGO, |
490 | ocfs2_max_locking_protocol_show, NULL); |
491 | |
492 | static ssize_t ocfs2_loaded_cluster_plugins_show(struct kobject *kobj, |
493 | struct kobj_attribute *attr, |
494 | char *buf) |
495 | { |
496 | ssize_t ret = 0, total = 0, remain = PAGE_SIZE; |
497 | struct ocfs2_stack_plugin *p; |
498 | |
499 | spin_lock(lock: &ocfs2_stack_lock); |
500 | list_for_each_entry(p, &ocfs2_stack_list, sp_list) { |
501 | ret = snprintf(buf, size: remain, fmt: "%s\n" , |
502 | p->sp_name); |
503 | if (ret >= remain) { |
504 | /* snprintf() didn't fit */ |
505 | total = -E2BIG; |
506 | break; |
507 | } |
508 | total += ret; |
509 | remain -= ret; |
510 | } |
511 | spin_unlock(lock: &ocfs2_stack_lock); |
512 | |
513 | return total; |
514 | } |
515 | |
516 | static struct kobj_attribute ocfs2_attr_loaded_cluster_plugins = |
517 | __ATTR(loaded_cluster_plugins, S_IRUGO, |
518 | ocfs2_loaded_cluster_plugins_show, NULL); |
519 | |
520 | static ssize_t ocfs2_active_cluster_plugin_show(struct kobject *kobj, |
521 | struct kobj_attribute *attr, |
522 | char *buf) |
523 | { |
524 | ssize_t ret = 0; |
525 | |
526 | spin_lock(lock: &ocfs2_stack_lock); |
527 | if (active_stack) { |
528 | ret = snprintf(buf, PAGE_SIZE, fmt: "%s\n" , |
529 | active_stack->sp_name); |
530 | if (ret >= PAGE_SIZE) |
531 | ret = -E2BIG; |
532 | } |
533 | spin_unlock(lock: &ocfs2_stack_lock); |
534 | |
535 | return ret; |
536 | } |
537 | |
538 | static struct kobj_attribute ocfs2_attr_active_cluster_plugin = |
539 | __ATTR(active_cluster_plugin, S_IRUGO, |
540 | ocfs2_active_cluster_plugin_show, NULL); |
541 | |
542 | static ssize_t ocfs2_cluster_stack_show(struct kobject *kobj, |
543 | struct kobj_attribute *attr, |
544 | char *buf) |
545 | { |
546 | ssize_t ret; |
547 | spin_lock(lock: &ocfs2_stack_lock); |
548 | ret = snprintf(buf, PAGE_SIZE, fmt: "%s\n" , cluster_stack_name); |
549 | spin_unlock(lock: &ocfs2_stack_lock); |
550 | |
551 | return ret; |
552 | } |
553 | |
554 | static ssize_t ocfs2_cluster_stack_store(struct kobject *kobj, |
555 | struct kobj_attribute *attr, |
556 | const char *buf, size_t count) |
557 | { |
558 | size_t len = count; |
559 | ssize_t ret; |
560 | |
561 | if (len == 0) |
562 | return len; |
563 | |
564 | if (buf[len - 1] == '\n') |
565 | len--; |
566 | |
567 | if ((len != OCFS2_STACK_LABEL_LEN) || |
568 | (strnlen(p: buf, maxlen: len) != len)) |
569 | return -EINVAL; |
570 | |
571 | spin_lock(lock: &ocfs2_stack_lock); |
572 | if (active_stack) { |
573 | if (!strncmp(buf, cluster_stack_name, len)) |
574 | ret = count; |
575 | else |
576 | ret = -EBUSY; |
577 | } else { |
578 | memcpy(cluster_stack_name, buf, len); |
579 | ret = count; |
580 | } |
581 | spin_unlock(lock: &ocfs2_stack_lock); |
582 | |
583 | return ret; |
584 | } |
585 | |
586 | |
587 | static struct kobj_attribute ocfs2_attr_cluster_stack = |
588 | __ATTR(cluster_stack, S_IRUGO | S_IWUSR, |
589 | ocfs2_cluster_stack_show, |
590 | ocfs2_cluster_stack_store); |
591 | |
592 | |
593 | |
594 | static ssize_t ocfs2_dlm_recover_show(struct kobject *kobj, |
595 | struct kobj_attribute *attr, |
596 | char *buf) |
597 | { |
598 | return snprintf(buf, PAGE_SIZE, fmt: "1\n" ); |
599 | } |
600 | |
601 | static struct kobj_attribute ocfs2_attr_dlm_recover_support = |
602 | __ATTR(dlm_recover_callback_support, S_IRUGO, |
603 | ocfs2_dlm_recover_show, NULL); |
604 | |
605 | static struct attribute *ocfs2_attrs[] = { |
606 | &ocfs2_attr_max_locking_protocol.attr, |
607 | &ocfs2_attr_loaded_cluster_plugins.attr, |
608 | &ocfs2_attr_active_cluster_plugin.attr, |
609 | &ocfs2_attr_cluster_stack.attr, |
610 | &ocfs2_attr_dlm_recover_support.attr, |
611 | NULL, |
612 | }; |
613 | |
614 | static const struct attribute_group ocfs2_attr_group = { |
615 | .attrs = ocfs2_attrs, |
616 | }; |
617 | |
618 | struct kset *ocfs2_kset; |
619 | EXPORT_SYMBOL_GPL(ocfs2_kset); |
620 | |
621 | static void ocfs2_sysfs_exit(void) |
622 | { |
623 | kset_unregister(kset: ocfs2_kset); |
624 | } |
625 | |
626 | static int ocfs2_sysfs_init(void) |
627 | { |
628 | int ret; |
629 | |
630 | ocfs2_kset = kset_create_and_add(name: "ocfs2" , NULL, parent_kobj: fs_kobj); |
631 | if (!ocfs2_kset) |
632 | return -ENOMEM; |
633 | |
634 | ret = sysfs_create_group(kobj: &ocfs2_kset->kobj, grp: &ocfs2_attr_group); |
635 | if (ret) |
636 | goto error; |
637 | |
638 | return 0; |
639 | |
640 | error: |
641 | kset_unregister(kset: ocfs2_kset); |
642 | return ret; |
643 | } |
644 | |
645 | /* |
646 | * Sysctl bits |
647 | * |
648 | * The sysctl lives at /proc/sys/fs/ocfs2/nm/hb_ctl_path. The 'nm' doesn't |
649 | * make as much sense in a multiple cluster stack world, but it's safer |
650 | * and easier to preserve the name. |
651 | */ |
652 | |
653 | static struct ctl_table ocfs2_nm_table[] = { |
654 | { |
655 | .procname = "hb_ctl_path" , |
656 | .data = ocfs2_hb_ctl_path, |
657 | .maxlen = OCFS2_MAX_HB_CTL_PATH, |
658 | .mode = 0644, |
659 | .proc_handler = proc_dostring, |
660 | }, |
661 | { } |
662 | }; |
663 | |
664 | static struct ctl_table_header *; |
665 | |
666 | /* |
667 | * Initialization |
668 | */ |
669 | |
670 | static int __init ocfs2_stack_glue_init(void) |
671 | { |
672 | int ret; |
673 | |
674 | strcpy(p: cluster_stack_name, OCFS2_STACK_PLUGIN_O2CB); |
675 | |
676 | ocfs2_table_header = register_sysctl("fs/ocfs2/nm" , ocfs2_nm_table); |
677 | if (!ocfs2_table_header) { |
678 | printk(KERN_ERR |
679 | "ocfs2 stack glue: unable to register sysctl\n" ); |
680 | return -ENOMEM; /* or something. */ |
681 | } |
682 | |
683 | ret = ocfs2_sysfs_init(); |
684 | if (ret) |
685 | unregister_sysctl_table(table: ocfs2_table_header); |
686 | |
687 | return ret; |
688 | } |
689 | |
690 | static void __exit ocfs2_stack_glue_exit(void) |
691 | { |
692 | memset(&locking_max_version, 0, |
693 | sizeof(struct ocfs2_protocol_version)); |
694 | ocfs2_sysfs_exit(); |
695 | if (ocfs2_table_header) |
696 | unregister_sysctl_table(table: ocfs2_table_header); |
697 | } |
698 | |
699 | MODULE_AUTHOR("Oracle" ); |
700 | MODULE_DESCRIPTION("ocfs2 cluster stack glue layer" ); |
701 | MODULE_LICENSE("GPL" ); |
702 | module_init(ocfs2_stack_glue_init); |
703 | module_exit(ocfs2_stack_glue_exit); |
704 | |