xref: /linux/fs/dlm/lockspace.c (revision f9aec1648df09d55436a0e3a94acff1df507751f)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /******************************************************************************
3 *******************************************************************************
4 **
5 **  Copyright (C) Sistina Software, Inc.  1997-2003  All rights reserved.
6 **  Copyright (C) 2004-2011 Red Hat, Inc.  All rights reserved.
7 **
8 **
9 *******************************************************************************
10 ******************************************************************************/
11 
12 #include <linux/module.h>
13 
14 #include "dlm_internal.h"
15 #include "lockspace.h"
16 #include "member.h"
17 #include "recoverd.h"
18 #include "dir.h"
19 #include "midcomms.h"
20 #include "lowcomms.h"
21 #include "config.h"
22 #include "memory.h"
23 #include "lock.h"
24 #include "recover.h"
25 #include "requestqueue.h"
26 #include "user.h"
27 #include "ast.h"
28 
29 static int			ls_count;
30 static struct mutex		ls_lock;
31 static struct list_head		lslist;
32 static spinlock_t		lslist_lock;
33 static struct task_struct *	scand_task;
34 
35 
36 static ssize_t dlm_control_store(struct dlm_ls *ls, const char *buf, size_t len)
37 {
38 	ssize_t ret = len;
39 	int n;
40 	int rc = kstrtoint(buf, 0, &n);
41 
42 	if (rc)
43 		return rc;
44 	ls = dlm_find_lockspace_local(ls->ls_local_handle);
45 	if (!ls)
46 		return -EINVAL;
47 
48 	switch (n) {
49 	case 0:
50 		dlm_ls_stop(ls);
51 		break;
52 	case 1:
53 		dlm_ls_start(ls);
54 		break;
55 	default:
56 		ret = -EINVAL;
57 	}
58 	dlm_put_lockspace(ls);
59 	return ret;
60 }
61 
62 static ssize_t dlm_event_store(struct dlm_ls *ls, const char *buf, size_t len)
63 {
64 	int rc = kstrtoint(buf, 0, &ls->ls_uevent_result);
65 
66 	if (rc)
67 		return rc;
68 	set_bit(LSFL_UEVENT_WAIT, &ls->ls_flags);
69 	wake_up(&ls->ls_uevent_wait);
70 	return len;
71 }
72 
73 static ssize_t dlm_id_show(struct dlm_ls *ls, char *buf)
74 {
75 	return snprintf(buf, PAGE_SIZE, "%u\n", ls->ls_global_id);
76 }
77 
78 static ssize_t dlm_id_store(struct dlm_ls *ls, const char *buf, size_t len)
79 {
80 	int rc = kstrtouint(buf, 0, &ls->ls_global_id);
81 
82 	if (rc)
83 		return rc;
84 	return len;
85 }
86 
87 static ssize_t dlm_nodir_show(struct dlm_ls *ls, char *buf)
88 {
89 	return snprintf(buf, PAGE_SIZE, "%u\n", dlm_no_directory(ls));
90 }
91 
92 static ssize_t dlm_nodir_store(struct dlm_ls *ls, const char *buf, size_t len)
93 {
94 	int val;
95 	int rc = kstrtoint(buf, 0, &val);
96 
97 	if (rc)
98 		return rc;
99 	if (val == 1)
100 		set_bit(LSFL_NODIR, &ls->ls_flags);
101 	return len;
102 }
103 
104 static ssize_t dlm_recover_status_show(struct dlm_ls *ls, char *buf)
105 {
106 	uint32_t status = dlm_recover_status(ls);
107 	return snprintf(buf, PAGE_SIZE, "%x\n", status);
108 }
109 
110 static ssize_t dlm_recover_nodeid_show(struct dlm_ls *ls, char *buf)
111 {
112 	return snprintf(buf, PAGE_SIZE, "%d\n", ls->ls_recover_nodeid);
113 }
114 
115 struct dlm_attr {
116 	struct attribute attr;
117 	ssize_t (*show)(struct dlm_ls *, char *);
118 	ssize_t (*store)(struct dlm_ls *, const char *, size_t);
119 };
120 
121 static struct dlm_attr dlm_attr_control = {
122 	.attr  = {.name = "control", .mode = S_IWUSR},
123 	.store = dlm_control_store
124 };
125 
126 static struct dlm_attr dlm_attr_event = {
127 	.attr  = {.name = "event_done", .mode = S_IWUSR},
128 	.store = dlm_event_store
129 };
130 
131 static struct dlm_attr dlm_attr_id = {
132 	.attr  = {.name = "id", .mode = S_IRUGO | S_IWUSR},
133 	.show  = dlm_id_show,
134 	.store = dlm_id_store
135 };
136 
137 static struct dlm_attr dlm_attr_nodir = {
138 	.attr  = {.name = "nodir", .mode = S_IRUGO | S_IWUSR},
139 	.show  = dlm_nodir_show,
140 	.store = dlm_nodir_store
141 };
142 
143 static struct dlm_attr dlm_attr_recover_status = {
144 	.attr  = {.name = "recover_status", .mode = S_IRUGO},
145 	.show  = dlm_recover_status_show
146 };
147 
148 static struct dlm_attr dlm_attr_recover_nodeid = {
149 	.attr  = {.name = "recover_nodeid", .mode = S_IRUGO},
150 	.show  = dlm_recover_nodeid_show
151 };
152 
153 static struct attribute *dlm_attrs[] = {
154 	&dlm_attr_control.attr,
155 	&dlm_attr_event.attr,
156 	&dlm_attr_id.attr,
157 	&dlm_attr_nodir.attr,
158 	&dlm_attr_recover_status.attr,
159 	&dlm_attr_recover_nodeid.attr,
160 	NULL,
161 };
162 ATTRIBUTE_GROUPS(dlm);
163 
164 static ssize_t dlm_attr_show(struct kobject *kobj, struct attribute *attr,
165 			     char *buf)
166 {
167 	struct dlm_ls *ls  = container_of(kobj, struct dlm_ls, ls_kobj);
168 	struct dlm_attr *a = container_of(attr, struct dlm_attr, attr);
169 	return a->show ? a->show(ls, buf) : 0;
170 }
171 
172 static ssize_t dlm_attr_store(struct kobject *kobj, struct attribute *attr,
173 			      const char *buf, size_t len)
174 {
175 	struct dlm_ls *ls  = container_of(kobj, struct dlm_ls, ls_kobj);
176 	struct dlm_attr *a = container_of(attr, struct dlm_attr, attr);
177 	return a->store ? a->store(ls, buf, len) : len;
178 }
179 
180 static void lockspace_kobj_release(struct kobject *k)
181 {
182 	struct dlm_ls *ls  = container_of(k, struct dlm_ls, ls_kobj);
183 	kfree(ls);
184 }
185 
186 static const struct sysfs_ops dlm_attr_ops = {
187 	.show  = dlm_attr_show,
188 	.store = dlm_attr_store,
189 };
190 
191 static struct kobj_type dlm_ktype = {
192 	.default_groups = dlm_groups,
193 	.sysfs_ops     = &dlm_attr_ops,
194 	.release       = lockspace_kobj_release,
195 };
196 
197 static struct kset *dlm_kset;
198 
199 static int do_uevent(struct dlm_ls *ls, int in)
200 {
201 	if (in)
202 		kobject_uevent(&ls->ls_kobj, KOBJ_ONLINE);
203 	else
204 		kobject_uevent(&ls->ls_kobj, KOBJ_OFFLINE);
205 
206 	log_rinfo(ls, "%s the lockspace group...", in ? "joining" : "leaving");
207 
208 	/* dlm_controld will see the uevent, do the necessary group management
209 	   and then write to sysfs to wake us */
210 
211 	wait_event(ls->ls_uevent_wait,
212 		   test_and_clear_bit(LSFL_UEVENT_WAIT, &ls->ls_flags));
213 
214 	log_rinfo(ls, "group event done %d", ls->ls_uevent_result);
215 
216 	return ls->ls_uevent_result;
217 }
218 
219 static int dlm_uevent(struct kset *kset, struct kobject *kobj,
220 		      struct kobj_uevent_env *env)
221 {
222 	struct dlm_ls *ls = container_of(kobj, struct dlm_ls, ls_kobj);
223 
224 	add_uevent_var(env, "LOCKSPACE=%s", ls->ls_name);
225 	return 0;
226 }
227 
228 static const struct kset_uevent_ops dlm_uevent_ops = {
229 	.uevent = dlm_uevent,
230 };
231 
232 int __init dlm_lockspace_init(void)
233 {
234 	ls_count = 0;
235 	mutex_init(&ls_lock);
236 	INIT_LIST_HEAD(&lslist);
237 	spin_lock_init(&lslist_lock);
238 
239 	dlm_kset = kset_create_and_add("dlm", &dlm_uevent_ops, kernel_kobj);
240 	if (!dlm_kset) {
241 		printk(KERN_WARNING "%s: can not create kset\n", __func__);
242 		return -ENOMEM;
243 	}
244 	return 0;
245 }
246 
247 void dlm_lockspace_exit(void)
248 {
249 	kset_unregister(dlm_kset);
250 }
251 
252 static struct dlm_ls *find_ls_to_scan(void)
253 {
254 	struct dlm_ls *ls;
255 
256 	spin_lock(&lslist_lock);
257 	list_for_each_entry(ls, &lslist, ls_list) {
258 		if (time_after_eq(jiffies, ls->ls_scan_time +
259 					    dlm_config.ci_scan_secs * HZ)) {
260 			spin_unlock(&lslist_lock);
261 			return ls;
262 		}
263 	}
264 	spin_unlock(&lslist_lock);
265 	return NULL;
266 }
267 
268 static int dlm_scand(void *data)
269 {
270 	struct dlm_ls *ls;
271 
272 	while (!kthread_should_stop()) {
273 		ls = find_ls_to_scan();
274 		if (ls) {
275 			if (dlm_lock_recovery_try(ls)) {
276 				ls->ls_scan_time = jiffies;
277 				dlm_scan_rsbs(ls);
278 				dlm_scan_timeout(ls);
279 				dlm_scan_waiters(ls);
280 				dlm_unlock_recovery(ls);
281 			} else {
282 				ls->ls_scan_time += HZ;
283 			}
284 			continue;
285 		}
286 		schedule_timeout_interruptible(dlm_config.ci_scan_secs * HZ);
287 	}
288 	return 0;
289 }
290 
291 static int dlm_scand_start(void)
292 {
293 	struct task_struct *p;
294 	int error = 0;
295 
296 	p = kthread_run(dlm_scand, NULL, "dlm_scand");
297 	if (IS_ERR(p))
298 		error = PTR_ERR(p);
299 	else
300 		scand_task = p;
301 	return error;
302 }
303 
304 static void dlm_scand_stop(void)
305 {
306 	kthread_stop(scand_task);
307 }
308 
309 struct dlm_ls *dlm_find_lockspace_global(uint32_t id)
310 {
311 	struct dlm_ls *ls;
312 
313 	spin_lock(&lslist_lock);
314 
315 	list_for_each_entry(ls, &lslist, ls_list) {
316 		if (ls->ls_global_id == id) {
317 			ls->ls_count++;
318 			goto out;
319 		}
320 	}
321 	ls = NULL;
322  out:
323 	spin_unlock(&lslist_lock);
324 	return ls;
325 }
326 
327 struct dlm_ls *dlm_find_lockspace_local(dlm_lockspace_t *lockspace)
328 {
329 	struct dlm_ls *ls;
330 
331 	spin_lock(&lslist_lock);
332 	list_for_each_entry(ls, &lslist, ls_list) {
333 		if (ls->ls_local_handle == lockspace) {
334 			ls->ls_count++;
335 			goto out;
336 		}
337 	}
338 	ls = NULL;
339  out:
340 	spin_unlock(&lslist_lock);
341 	return ls;
342 }
343 
344 struct dlm_ls *dlm_find_lockspace_device(int minor)
345 {
346 	struct dlm_ls *ls;
347 
348 	spin_lock(&lslist_lock);
349 	list_for_each_entry(ls, &lslist, ls_list) {
350 		if (ls->ls_device.minor == minor) {
351 			ls->ls_count++;
352 			goto out;
353 		}
354 	}
355 	ls = NULL;
356  out:
357 	spin_unlock(&lslist_lock);
358 	return ls;
359 }
360 
361 void dlm_put_lockspace(struct dlm_ls *ls)
362 {
363 	spin_lock(&lslist_lock);
364 	ls->ls_count--;
365 	spin_unlock(&lslist_lock);
366 }
367 
368 static void remove_lockspace(struct dlm_ls *ls)
369 {
370 	for (;;) {
371 		spin_lock(&lslist_lock);
372 		if (ls->ls_count == 0) {
373 			WARN_ON(ls->ls_create_count != 0);
374 			list_del(&ls->ls_list);
375 			spin_unlock(&lslist_lock);
376 			return;
377 		}
378 		spin_unlock(&lslist_lock);
379 		ssleep(1);
380 	}
381 }
382 
383 static int threads_start(void)
384 {
385 	int error;
386 
387 	error = dlm_scand_start();
388 	if (error) {
389 		log_print("cannot start dlm_scand thread %d", error);
390 		goto fail;
391 	}
392 
393 	/* Thread for sending/receiving messages for all lockspace's */
394 	error = dlm_midcomms_start();
395 	if (error) {
396 		log_print("cannot start dlm lowcomms %d", error);
397 		goto scand_fail;
398 	}
399 
400 	return 0;
401 
402  scand_fail:
403 	dlm_scand_stop();
404  fail:
405 	return error;
406 }
407 
408 static int new_lockspace(const char *name, const char *cluster,
409 			 uint32_t flags, int lvblen,
410 			 const struct dlm_lockspace_ops *ops, void *ops_arg,
411 			 int *ops_result, dlm_lockspace_t **lockspace)
412 {
413 	struct dlm_ls *ls;
414 	int i, size, error;
415 	int do_unreg = 0;
416 	int namelen = strlen(name);
417 
418 	if (namelen > DLM_LOCKSPACE_LEN || namelen == 0)
419 		return -EINVAL;
420 
421 	if (!lvblen || (lvblen % 8))
422 		return -EINVAL;
423 
424 	if (!try_module_get(THIS_MODULE))
425 		return -EINVAL;
426 
427 	if (!dlm_user_daemon_available()) {
428 		log_print("dlm user daemon not available");
429 		error = -EUNATCH;
430 		goto out;
431 	}
432 
433 	if (ops && ops_result) {
434 	       	if (!dlm_config.ci_recover_callbacks)
435 			*ops_result = -EOPNOTSUPP;
436 		else
437 			*ops_result = 0;
438 	}
439 
440 	if (!cluster)
441 		log_print("dlm cluster name '%s' is being used without an application provided cluster name",
442 			  dlm_config.ci_cluster_name);
443 
444 	if (dlm_config.ci_recover_callbacks && cluster &&
445 	    strncmp(cluster, dlm_config.ci_cluster_name, DLM_LOCKSPACE_LEN)) {
446 		log_print("dlm cluster name '%s' does not match "
447 			  "the application cluster name '%s'",
448 			  dlm_config.ci_cluster_name, cluster);
449 		error = -EBADR;
450 		goto out;
451 	}
452 
453 	error = 0;
454 
455 	spin_lock(&lslist_lock);
456 	list_for_each_entry(ls, &lslist, ls_list) {
457 		WARN_ON(ls->ls_create_count <= 0);
458 		if (ls->ls_namelen != namelen)
459 			continue;
460 		if (memcmp(ls->ls_name, name, namelen))
461 			continue;
462 		if (flags & DLM_LSFL_NEWEXCL) {
463 			error = -EEXIST;
464 			break;
465 		}
466 		ls->ls_create_count++;
467 		*lockspace = ls;
468 		error = 1;
469 		break;
470 	}
471 	spin_unlock(&lslist_lock);
472 
473 	if (error)
474 		goto out;
475 
476 	error = -ENOMEM;
477 
478 	ls = kzalloc(sizeof(struct dlm_ls) + namelen, GFP_NOFS);
479 	if (!ls)
480 		goto out;
481 	memcpy(ls->ls_name, name, namelen);
482 	ls->ls_namelen = namelen;
483 	ls->ls_lvblen = lvblen;
484 	ls->ls_count = 0;
485 	ls->ls_flags = 0;
486 	ls->ls_scan_time = jiffies;
487 
488 	if (ops && dlm_config.ci_recover_callbacks) {
489 		ls->ls_ops = ops;
490 		ls->ls_ops_arg = ops_arg;
491 	}
492 
493 	if (flags & DLM_LSFL_TIMEWARN)
494 		set_bit(LSFL_TIMEWARN, &ls->ls_flags);
495 
496 	/* ls_exflags are forced to match among nodes, and we don't
497 	   need to require all nodes to have some flags set */
498 	ls->ls_exflags = (flags & ~(DLM_LSFL_TIMEWARN | DLM_LSFL_FS |
499 				    DLM_LSFL_NEWEXCL));
500 
501 	size = READ_ONCE(dlm_config.ci_rsbtbl_size);
502 	ls->ls_rsbtbl_size = size;
503 
504 	ls->ls_rsbtbl = vmalloc(array_size(size, sizeof(struct dlm_rsbtable)));
505 	if (!ls->ls_rsbtbl)
506 		goto out_lsfree;
507 	for (i = 0; i < size; i++) {
508 		ls->ls_rsbtbl[i].keep.rb_node = NULL;
509 		ls->ls_rsbtbl[i].toss.rb_node = NULL;
510 		spin_lock_init(&ls->ls_rsbtbl[i].lock);
511 	}
512 
513 	spin_lock_init(&ls->ls_remove_spin);
514 
515 	for (i = 0; i < DLM_REMOVE_NAMES_MAX; i++) {
516 		ls->ls_remove_names[i] = kzalloc(DLM_RESNAME_MAXLEN+1,
517 						 GFP_KERNEL);
518 		if (!ls->ls_remove_names[i])
519 			goto out_rsbtbl;
520 	}
521 
522 	idr_init(&ls->ls_lkbidr);
523 	spin_lock_init(&ls->ls_lkbidr_spin);
524 
525 	INIT_LIST_HEAD(&ls->ls_waiters);
526 	mutex_init(&ls->ls_waiters_mutex);
527 	INIT_LIST_HEAD(&ls->ls_orphans);
528 	mutex_init(&ls->ls_orphans_mutex);
529 	INIT_LIST_HEAD(&ls->ls_timeout);
530 	mutex_init(&ls->ls_timeout_mutex);
531 
532 	INIT_LIST_HEAD(&ls->ls_new_rsb);
533 	spin_lock_init(&ls->ls_new_rsb_spin);
534 
535 	INIT_LIST_HEAD(&ls->ls_nodes);
536 	INIT_LIST_HEAD(&ls->ls_nodes_gone);
537 	ls->ls_num_nodes = 0;
538 	ls->ls_low_nodeid = 0;
539 	ls->ls_total_weight = 0;
540 	ls->ls_node_array = NULL;
541 
542 	memset(&ls->ls_stub_rsb, 0, sizeof(struct dlm_rsb));
543 	ls->ls_stub_rsb.res_ls = ls;
544 
545 	ls->ls_debug_rsb_dentry = NULL;
546 	ls->ls_debug_waiters_dentry = NULL;
547 
548 	init_waitqueue_head(&ls->ls_uevent_wait);
549 	ls->ls_uevent_result = 0;
550 	init_completion(&ls->ls_members_done);
551 	ls->ls_members_result = -1;
552 
553 	mutex_init(&ls->ls_cb_mutex);
554 	INIT_LIST_HEAD(&ls->ls_cb_delay);
555 
556 	ls->ls_recoverd_task = NULL;
557 	mutex_init(&ls->ls_recoverd_active);
558 	spin_lock_init(&ls->ls_recover_lock);
559 	spin_lock_init(&ls->ls_rcom_spin);
560 	get_random_bytes(&ls->ls_rcom_seq, sizeof(uint64_t));
561 	ls->ls_recover_status = 0;
562 	ls->ls_recover_seq = 0;
563 	ls->ls_recover_args = NULL;
564 	init_rwsem(&ls->ls_in_recovery);
565 	init_rwsem(&ls->ls_recv_active);
566 	INIT_LIST_HEAD(&ls->ls_requestqueue);
567 	mutex_init(&ls->ls_requestqueue_mutex);
568 	mutex_init(&ls->ls_clear_proc_locks);
569 
570 	/* Due backwards compatibility with 3.1 we need to use maximum
571 	 * possible dlm message size to be sure the message will fit and
572 	 * not having out of bounds issues. However on sending side 3.2
573 	 * might send less.
574 	 */
575 	ls->ls_recover_buf = kmalloc(DLM_MAX_SOCKET_BUFSIZE, GFP_NOFS);
576 	if (!ls->ls_recover_buf)
577 		goto out_lkbidr;
578 
579 	ls->ls_slot = 0;
580 	ls->ls_num_slots = 0;
581 	ls->ls_slots_size = 0;
582 	ls->ls_slots = NULL;
583 
584 	INIT_LIST_HEAD(&ls->ls_recover_list);
585 	spin_lock_init(&ls->ls_recover_list_lock);
586 	idr_init(&ls->ls_recover_idr);
587 	spin_lock_init(&ls->ls_recover_idr_lock);
588 	ls->ls_recover_list_count = 0;
589 	ls->ls_local_handle = ls;
590 	init_waitqueue_head(&ls->ls_wait_general);
591 	INIT_LIST_HEAD(&ls->ls_root_list);
592 	init_rwsem(&ls->ls_root_sem);
593 
594 	spin_lock(&lslist_lock);
595 	ls->ls_create_count = 1;
596 	list_add(&ls->ls_list, &lslist);
597 	spin_unlock(&lslist_lock);
598 
599 	if (flags & DLM_LSFL_FS) {
600 		error = dlm_callback_start(ls);
601 		if (error) {
602 			log_error(ls, "can't start dlm_callback %d", error);
603 			goto out_delist;
604 		}
605 	}
606 
607 	init_waitqueue_head(&ls->ls_recover_lock_wait);
608 
609 	/*
610 	 * Once started, dlm_recoverd first looks for ls in lslist, then
611 	 * initializes ls_in_recovery as locked in "down" mode.  We need
612 	 * to wait for the wakeup from dlm_recoverd because in_recovery
613 	 * has to start out in down mode.
614 	 */
615 
616 	error = dlm_recoverd_start(ls);
617 	if (error) {
618 		log_error(ls, "can't start dlm_recoverd %d", error);
619 		goto out_callback;
620 	}
621 
622 	wait_event(ls->ls_recover_lock_wait,
623 		   test_bit(LSFL_RECOVER_LOCK, &ls->ls_flags));
624 
625 	/* let kobject handle freeing of ls if there's an error */
626 	do_unreg = 1;
627 
628 	ls->ls_kobj.kset = dlm_kset;
629 	error = kobject_init_and_add(&ls->ls_kobj, &dlm_ktype, NULL,
630 				     "%s", ls->ls_name);
631 	if (error)
632 		goto out_recoverd;
633 	kobject_uevent(&ls->ls_kobj, KOBJ_ADD);
634 
635 	/* This uevent triggers dlm_controld in userspace to add us to the
636 	   group of nodes that are members of this lockspace (managed by the
637 	   cluster infrastructure.)  Once it's done that, it tells us who the
638 	   current lockspace members are (via configfs) and then tells the
639 	   lockspace to start running (via sysfs) in dlm_ls_start(). */
640 
641 	error = do_uevent(ls, 1);
642 	if (error)
643 		goto out_recoverd;
644 
645 	wait_for_completion(&ls->ls_members_done);
646 	error = ls->ls_members_result;
647 	if (error)
648 		goto out_members;
649 
650 	dlm_create_debug_file(ls);
651 
652 	log_rinfo(ls, "join complete");
653 	*lockspace = ls;
654 	return 0;
655 
656  out_members:
657 	do_uevent(ls, 0);
658 	dlm_clear_members(ls);
659 	kfree(ls->ls_node_array);
660  out_recoverd:
661 	dlm_recoverd_stop(ls);
662  out_callback:
663 	dlm_callback_stop(ls);
664  out_delist:
665 	spin_lock(&lslist_lock);
666 	list_del(&ls->ls_list);
667 	spin_unlock(&lslist_lock);
668 	idr_destroy(&ls->ls_recover_idr);
669 	kfree(ls->ls_recover_buf);
670  out_lkbidr:
671 	idr_destroy(&ls->ls_lkbidr);
672  out_rsbtbl:
673 	for (i = 0; i < DLM_REMOVE_NAMES_MAX; i++)
674 		kfree(ls->ls_remove_names[i]);
675 	vfree(ls->ls_rsbtbl);
676  out_lsfree:
677 	if (do_unreg)
678 		kobject_put(&ls->ls_kobj);
679 	else
680 		kfree(ls);
681  out:
682 	module_put(THIS_MODULE);
683 	return error;
684 }
685 
686 int dlm_new_lockspace(const char *name, const char *cluster,
687 		      uint32_t flags, int lvblen,
688 		      const struct dlm_lockspace_ops *ops, void *ops_arg,
689 		      int *ops_result, dlm_lockspace_t **lockspace)
690 {
691 	int error = 0;
692 
693 	mutex_lock(&ls_lock);
694 	if (!ls_count)
695 		error = threads_start();
696 	if (error)
697 		goto out;
698 
699 	error = new_lockspace(name, cluster, flags, lvblen, ops, ops_arg,
700 			      ops_result, lockspace);
701 	if (!error)
702 		ls_count++;
703 	if (error > 0)
704 		error = 0;
705 	if (!ls_count) {
706 		dlm_scand_stop();
707 		dlm_midcomms_shutdown();
708 		dlm_lowcomms_stop();
709 	}
710  out:
711 	mutex_unlock(&ls_lock);
712 	return error;
713 }
714 
715 static int lkb_idr_is_local(int id, void *p, void *data)
716 {
717 	struct dlm_lkb *lkb = p;
718 
719 	return lkb->lkb_nodeid == 0 && lkb->lkb_grmode != DLM_LOCK_IV;
720 }
721 
722 static int lkb_idr_is_any(int id, void *p, void *data)
723 {
724 	return 1;
725 }
726 
727 static int lkb_idr_free(int id, void *p, void *data)
728 {
729 	struct dlm_lkb *lkb = p;
730 
731 	if (lkb->lkb_lvbptr && lkb->lkb_flags & DLM_IFL_MSTCPY)
732 		dlm_free_lvb(lkb->lkb_lvbptr);
733 
734 	dlm_free_lkb(lkb);
735 	return 0;
736 }
737 
738 /* NOTE: We check the lkbidr here rather than the resource table.
739    This is because there may be LKBs queued as ASTs that have been unlinked
740    from their RSBs and are pending deletion once the AST has been delivered */
741 
742 static int lockspace_busy(struct dlm_ls *ls, int force)
743 {
744 	int rv;
745 
746 	spin_lock(&ls->ls_lkbidr_spin);
747 	if (force == 0) {
748 		rv = idr_for_each(&ls->ls_lkbidr, lkb_idr_is_any, ls);
749 	} else if (force == 1) {
750 		rv = idr_for_each(&ls->ls_lkbidr, lkb_idr_is_local, ls);
751 	} else {
752 		rv = 0;
753 	}
754 	spin_unlock(&ls->ls_lkbidr_spin);
755 	return rv;
756 }
757 
758 static int release_lockspace(struct dlm_ls *ls, int force)
759 {
760 	struct dlm_rsb *rsb;
761 	struct rb_node *n;
762 	int i, busy, rv;
763 
764 	busy = lockspace_busy(ls, force);
765 
766 	spin_lock(&lslist_lock);
767 	if (ls->ls_create_count == 1) {
768 		if (busy) {
769 			rv = -EBUSY;
770 		} else {
771 			/* remove_lockspace takes ls off lslist */
772 			ls->ls_create_count = 0;
773 			rv = 0;
774 		}
775 	} else if (ls->ls_create_count > 1) {
776 		rv = --ls->ls_create_count;
777 	} else {
778 		rv = -EINVAL;
779 	}
780 	spin_unlock(&lslist_lock);
781 
782 	if (rv) {
783 		log_debug(ls, "release_lockspace no remove %d", rv);
784 		return rv;
785 	}
786 
787 	dlm_device_deregister(ls);
788 
789 	if (force < 3 && dlm_user_daemon_available())
790 		do_uevent(ls, 0);
791 
792 	dlm_recoverd_stop(ls);
793 
794 	if (ls_count == 1) {
795 		dlm_scand_stop();
796 		dlm_clear_members(ls);
797 		dlm_midcomms_shutdown();
798 	}
799 
800 	dlm_callback_stop(ls);
801 
802 	remove_lockspace(ls);
803 
804 	dlm_delete_debug_file(ls);
805 
806 	idr_destroy(&ls->ls_recover_idr);
807 	kfree(ls->ls_recover_buf);
808 
809 	/*
810 	 * Free all lkb's in idr
811 	 */
812 
813 	idr_for_each(&ls->ls_lkbidr, lkb_idr_free, ls);
814 	idr_destroy(&ls->ls_lkbidr);
815 
816 	/*
817 	 * Free all rsb's on rsbtbl[] lists
818 	 */
819 
820 	for (i = 0; i < ls->ls_rsbtbl_size; i++) {
821 		while ((n = rb_first(&ls->ls_rsbtbl[i].keep))) {
822 			rsb = rb_entry(n, struct dlm_rsb, res_hashnode);
823 			rb_erase(n, &ls->ls_rsbtbl[i].keep);
824 			dlm_free_rsb(rsb);
825 		}
826 
827 		while ((n = rb_first(&ls->ls_rsbtbl[i].toss))) {
828 			rsb = rb_entry(n, struct dlm_rsb, res_hashnode);
829 			rb_erase(n, &ls->ls_rsbtbl[i].toss);
830 			dlm_free_rsb(rsb);
831 		}
832 	}
833 
834 	vfree(ls->ls_rsbtbl);
835 
836 	for (i = 0; i < DLM_REMOVE_NAMES_MAX; i++)
837 		kfree(ls->ls_remove_names[i]);
838 
839 	while (!list_empty(&ls->ls_new_rsb)) {
840 		rsb = list_first_entry(&ls->ls_new_rsb, struct dlm_rsb,
841 				       res_hashchain);
842 		list_del(&rsb->res_hashchain);
843 		dlm_free_rsb(rsb);
844 	}
845 
846 	/*
847 	 * Free structures on any other lists
848 	 */
849 
850 	dlm_purge_requestqueue(ls);
851 	kfree(ls->ls_recover_args);
852 	dlm_clear_members(ls);
853 	dlm_clear_members_gone(ls);
854 	kfree(ls->ls_node_array);
855 	log_rinfo(ls, "release_lockspace final free");
856 	kobject_put(&ls->ls_kobj);
857 	/* The ls structure will be freed when the kobject is done with */
858 
859 	module_put(THIS_MODULE);
860 	return 0;
861 }
862 
863 /*
864  * Called when a system has released all its locks and is not going to use the
865  * lockspace any longer.  We free everything we're managing for this lockspace.
866  * Remaining nodes will go through the recovery process as if we'd died.  The
867  * lockspace must continue to function as usual, participating in recoveries,
868  * until this returns.
869  *
870  * Force has 4 possible values:
871  * 0 - don't destroy locksapce if it has any LKBs
872  * 1 - destroy lockspace if it has remote LKBs but not if it has local LKBs
873  * 2 - destroy lockspace regardless of LKBs
874  * 3 - destroy lockspace as part of a forced shutdown
875  */
876 
877 int dlm_release_lockspace(void *lockspace, int force)
878 {
879 	struct dlm_ls *ls;
880 	int error;
881 
882 	ls = dlm_find_lockspace_local(lockspace);
883 	if (!ls)
884 		return -EINVAL;
885 	dlm_put_lockspace(ls);
886 
887 	mutex_lock(&ls_lock);
888 	error = release_lockspace(ls, force);
889 	if (!error)
890 		ls_count--;
891 	if (!ls_count)
892 		dlm_lowcomms_stop();
893 	mutex_unlock(&ls_lock);
894 
895 	return error;
896 }
897 
898 void dlm_stop_lockspaces(void)
899 {
900 	struct dlm_ls *ls;
901 	int count;
902 
903  restart:
904 	count = 0;
905 	spin_lock(&lslist_lock);
906 	list_for_each_entry(ls, &lslist, ls_list) {
907 		if (!test_bit(LSFL_RUNNING, &ls->ls_flags)) {
908 			count++;
909 			continue;
910 		}
911 		spin_unlock(&lslist_lock);
912 		log_error(ls, "no userland control daemon, stopping lockspace");
913 		dlm_ls_stop(ls);
914 		goto restart;
915 	}
916 	spin_unlock(&lslist_lock);
917 
918 	if (count)
919 		log_print("dlm user daemon left %d lockspaces", count);
920 }
921 
922