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include: replace linux/module.h with "struct module" wherever possible
[linux-2.6/next.git] / fs / ocfs2 / dlm / dlmdomain.c
blob6ed6b95dcf935a6516e935b85a3ca9ffc0b8a9d8
1 /* -*- mode: c; c-basic-offset: 8; -*-
2 * vim: noexpandtab sw=8 ts=8 sts=0:
3 *
4 * dlmdomain.c
5 *
6 * defines domain join / leave apis
7 *
8 * Copyright (C) 2004 Oracle. All rights reserved.
9 *
10 * This program is free software; you can redistribute it and/or
11 * modify it under the terms of the GNU General Public
12 * License as published by the Free Software Foundation; either
13 * version 2 of the License, or (at your option) any later version.
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 * You should have received a copy of the GNU General Public
21 * License along with this program; if not, write to the
22 * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
23 * Boston, MA 021110-1307, USA.
24 *
25 */
26
27 #include <linux/module.h>
28 #include <linux/types.h>
29 #include <linux/slab.h>
30 #include <linux/highmem.h>
31 #include <linux/init.h>
32 #include <linux/spinlock.h>
33 #include <linux/delay.h>
34 #include <linux/err.h>
35 #include <linux/debugfs.h>
36
37 #include "cluster/heartbeat.h"
38 #include "cluster/nodemanager.h"
39 #include "cluster/tcp.h"
40
41 #include "dlmapi.h"
42 #include "dlmcommon.h"
43 #include "dlmdomain.h"
44 #include "dlmdebug.h"
45
46 #include "dlmver.h"
47
48 #define MLOG_MASK_PREFIX (ML_DLM|ML_DLM_DOMAIN)
49 #include "cluster/masklog.h"
50
51 /*
52 * ocfs2 node maps are array of long int, which limits to send them freely
53 * across the wire due to endianness issues. To workaround this, we convert
54 * long ints to byte arrays. Following 3 routines are helper functions to
55 * set/test/copy bits within those array of bytes
56 */
57 static inline void byte_set_bit(u8 nr, u8 map[])
58 {
59 map[nr >> 3] |= (1UL << (nr & 7));
60 }
61
62 static inline int byte_test_bit(u8 nr, u8 map[])
63 {
64 return ((1UL << (nr & 7)) & (map[nr >> 3])) != 0;
65 }
66
67 static inline void byte_copymap(u8 dmap[], unsigned long smap[],
68 unsigned int sz)
69 {
70 unsigned int nn;
71
72 if (!sz)
73 return;
74
75 memset(dmap, 0, ((sz + 7) >> 3));
76 for (nn = 0 ; nn < sz; nn++)
77 if (test_bit(nn, smap))
78 byte_set_bit(nn, dmap);
79 }
80
81 static void dlm_free_pagevec(void **vec, int pages)
82 {
83 while (pages--)
84 free_page((unsigned long)vec[pages]);
85 kfree(vec);
86 }
87
88 static void **dlm_alloc_pagevec(int pages)
89 {
90 void **vec = kmalloc(pages * sizeof(void *), GFP_KERNEL);
91 int i;
92
93 if (!vec)
94 return NULL;
95
96 for (i = 0; i < pages; i++)
97 if (!(vec[i] = (void *)__get_free_page(GFP_KERNEL)))
98 goto out_free;
99
100 mlog(0, "Allocated DLM hash pagevec; %d pages (%lu expected), %lu buckets per page\n",
101 pages, (unsigned long)DLM_HASH_PAGES,
102 (unsigned long)DLM_BUCKETS_PER_PAGE);
103 return vec;
104 out_free:
105 dlm_free_pagevec(vec, i);
106 return NULL;
107 }
108
109 /*
110 *
111 * spinlock lock ordering: if multiple locks are needed, obey this ordering:
112 * dlm_domain_lock
113 * struct dlm_ctxt->spinlock
114 * struct dlm_lock_resource->spinlock
115 * struct dlm_ctxt->master_lock
116 * struct dlm_ctxt->ast_lock
117 * dlm_master_list_entry->spinlock
118 * dlm_lock->spinlock
119 *
120 */
121
122 DEFINE_SPINLOCK(dlm_domain_lock);
123 LIST_HEAD(dlm_domains);
124 static DECLARE_WAIT_QUEUE_HEAD(dlm_domain_events);
125
126 /*
127 * The supported protocol version for DLM communication. Running domains
128 * will have a negotiated version with the same major number and a minor
129 * number equal or smaller. The dlm_ctxt->dlm_locking_proto field should
130 * be used to determine what a running domain is actually using.
131 *
132 * New in version 1.1:
133 * - Message DLM_QUERY_REGION added to support global heartbeat
134 * - Message DLM_QUERY_NODEINFO added to allow online node removes
135 * New in version 1.2:
136 * - Message DLM_BEGIN_EXIT_DOMAIN_MSG added to mark start of exit domain
137 */
138 static const struct dlm_protocol_version dlm_protocol = {
139 .pv_major = 1,
140 .pv_minor = 2,
141 };
142
143 #define DLM_DOMAIN_BACKOFF_MS 200
144
145 static int dlm_query_join_handler(struct o2net_msg *msg, u32 len, void *data,
146 void **ret_data);
147 static int dlm_assert_joined_handler(struct o2net_msg *msg, u32 len, void *data,
148 void **ret_data);
149 static int dlm_cancel_join_handler(struct o2net_msg *msg, u32 len, void *data,
150 void **ret_data);
151 static int dlm_query_region_handler(struct o2net_msg *msg, u32 len,
152 void *data, void **ret_data);
153 static int dlm_exit_domain_handler(struct o2net_msg *msg, u32 len, void *data,
154 void **ret_data);
155 static int dlm_protocol_compare(struct dlm_protocol_version *existing,
156 struct dlm_protocol_version *request);
157
158 static void dlm_unregister_domain_handlers(struct dlm_ctxt *dlm);
159
160 void __dlm_unhash_lockres(struct dlm_lock_resource *lockres)
161 {
162 if (!hlist_unhashed(&lockres->hash_node)) {
163 hlist_del_init(&lockres->hash_node);
164 dlm_lockres_put(lockres);
165 }
166 }
167
168 void __dlm_insert_lockres(struct dlm_ctxt *dlm,
169 struct dlm_lock_resource *res)
170 {
171 struct hlist_head *bucket;
172 struct qstr *q;
173
174 assert_spin_locked(&dlm->spinlock);
175
176 q = &res->lockname;
177 bucket = dlm_lockres_hash(dlm, q->hash);
178
179 /* get a reference for our hashtable */
180 dlm_lockres_get(res);
181
182 hlist_add_head(&res->hash_node, bucket);
183 }
184
185 struct dlm_lock_resource * __dlm_lookup_lockres_full(struct dlm_ctxt *dlm,
186 const char *name,
187 unsigned int len,
188 unsigned int hash)
189 {
190 struct hlist_head *bucket;
191 struct hlist_node *list;
192
193 mlog(0, "%.*s\n", len, name);
194
195 assert_spin_locked(&dlm->spinlock);
196
197 bucket = dlm_lockres_hash(dlm, hash);
198
199 hlist_for_each(list, bucket) {
200 struct dlm_lock_resource *res = hlist_entry(list,
201 struct dlm_lock_resource, hash_node);
202 if (res->lockname.name[0] != name[0])
203 continue;
204 if (unlikely(res->lockname.len != len))
205 continue;
206 if (memcmp(res->lockname.name + 1, name + 1, len - 1))
207 continue;
208 dlm_lockres_get(res);
209 return res;
210 }
211 return NULL;
212 }
213
214 /* intended to be called by functions which do not care about lock
215 * resources which are being purged (most net _handler functions).
216 * this will return NULL for any lock resource which is found but
217 * currently in the process of dropping its mastery reference.
218 * use __dlm_lookup_lockres_full when you need the lock resource
219 * regardless (e.g. dlm_get_lock_resource) */
220 struct dlm_lock_resource * __dlm_lookup_lockres(struct dlm_ctxt *dlm,
221 const char *name,
222 unsigned int len,
223 unsigned int hash)
224 {
225 struct dlm_lock_resource *res = NULL;
226
227 mlog(0, "%.*s\n", len, name);
228
229 assert_spin_locked(&dlm->spinlock);
230
231 res = __dlm_lookup_lockres_full(dlm, name, len, hash);
232 if (res) {
233 spin_lock(&res->spinlock);
234 if (res->state & DLM_LOCK_RES_DROPPING_REF) {
235 spin_unlock(&res->spinlock);
236 dlm_lockres_put(res);
237 return NULL;
238 }
239 spin_unlock(&res->spinlock);
240 }
241
242 return res;
243 }
244
245 struct dlm_lock_resource * dlm_lookup_lockres(struct dlm_ctxt *dlm,
246 const char *name,
247 unsigned int len)
248 {
249 struct dlm_lock_resource *res;
250 unsigned int hash = dlm_lockid_hash(name, len);
251
252 spin_lock(&dlm->spinlock);
253 res = __dlm_lookup_lockres(dlm, name, len, hash);
254 spin_unlock(&dlm->spinlock);
255 return res;
256 }
257
258 static struct dlm_ctxt * __dlm_lookup_domain_full(const char *domain, int len)
259 {
260 struct dlm_ctxt *tmp = NULL;
261 struct list_head *iter;
262
263 assert_spin_locked(&dlm_domain_lock);
264
265 /* tmp->name here is always NULL terminated,
266 * but domain may not be! */
267 list_for_each(iter, &dlm_domains) {
268 tmp = list_entry (iter, struct dlm_ctxt, list);
269 if (strlen(tmp->name) == len &&
270 memcmp(tmp->name, domain, len)==0)
271 break;
272 tmp = NULL;
273 }
274
275 return tmp;
276 }
277
278 /* For null terminated domain strings ONLY */
279 static struct dlm_ctxt * __dlm_lookup_domain(const char *domain)
280 {
281 assert_spin_locked(&dlm_domain_lock);
282
283 return __dlm_lookup_domain_full(domain, strlen(domain));
284 }
285
286
287 /* returns true on one of two conditions:
288 * 1) the domain does not exist
289 * 2) the domain exists and it's state is "joined" */
290 static int dlm_wait_on_domain_helper(const char *domain)
291 {
292 int ret = 0;
293 struct dlm_ctxt *tmp = NULL;
294
295 spin_lock(&dlm_domain_lock);
296
297 tmp = __dlm_lookup_domain(domain);
298 if (!tmp)
299 ret = 1;
300 else if (tmp->dlm_state == DLM_CTXT_JOINED)
301 ret = 1;
302
303 spin_unlock(&dlm_domain_lock);
304 return ret;
305 }
306
307 static void dlm_free_ctxt_mem(struct dlm_ctxt *dlm)
308 {
309 dlm_destroy_debugfs_subroot(dlm);
310
311 if (dlm->lockres_hash)
312 dlm_free_pagevec((void **)dlm->lockres_hash, DLM_HASH_PAGES);
313
314 if (dlm->master_hash)
315 dlm_free_pagevec((void **)dlm->master_hash, DLM_HASH_PAGES);
316
317 if (dlm->name)
318 kfree(dlm->name);
319
320 kfree(dlm);
321 }
322
323 /* A little strange - this function will be called while holding
324 * dlm_domain_lock and is expected to be holding it on the way out. We
325 * will however drop and reacquire it multiple times */
326 static void dlm_ctxt_release(struct kref *kref)
327 {
328 struct dlm_ctxt *dlm;
329
330 dlm = container_of(kref, struct dlm_ctxt, dlm_refs);
331
332 BUG_ON(dlm->num_joins);
333 BUG_ON(dlm->dlm_state == DLM_CTXT_JOINED);
334
335 /* we may still be in the list if we hit an error during join. */
336 list_del_init(&dlm->list);
337
338 spin_unlock(&dlm_domain_lock);
339
340 mlog(0, "freeing memory from domain %s\n", dlm->name);
341
342 wake_up(&dlm_domain_events);
343
344 dlm_free_ctxt_mem(dlm);
345
346 spin_lock(&dlm_domain_lock);
347 }
348
349 void dlm_put(struct dlm_ctxt *dlm)
350 {
351 spin_lock(&dlm_domain_lock);
352 kref_put(&dlm->dlm_refs, dlm_ctxt_release);
353 spin_unlock(&dlm_domain_lock);
354 }
355
356 static void __dlm_get(struct dlm_ctxt *dlm)
357 {
358 kref_get(&dlm->dlm_refs);
359 }
360
361 /* given a questionable reference to a dlm object, gets a reference if
362 * it can find it in the list, otherwise returns NULL in which case
363 * you shouldn't trust your pointer. */
364 struct dlm_ctxt *dlm_grab(struct dlm_ctxt *dlm)
365 {
366 struct list_head *iter;
367 struct dlm_ctxt *target = NULL;
368
369 spin_lock(&dlm_domain_lock);
370
371 list_for_each(iter, &dlm_domains) {
372 target = list_entry (iter, struct dlm_ctxt, list);
373
374 if (target == dlm) {
375 __dlm_get(target);
376 break;
377 }
378
379 target = NULL;
380 }
381
382 spin_unlock(&dlm_domain_lock);
383
384 return target;
385 }
386
387 int dlm_domain_fully_joined(struct dlm_ctxt *dlm)
388 {
389 int ret;
390
391 spin_lock(&dlm_domain_lock);
392 ret = (dlm->dlm_state == DLM_CTXT_JOINED) ||
393 (dlm->dlm_state == DLM_CTXT_IN_SHUTDOWN);
394 spin_unlock(&dlm_domain_lock);
395
396 return ret;
397 }
398
399 static void dlm_destroy_dlm_worker(struct dlm_ctxt *dlm)
400 {
401 if (dlm->dlm_worker) {
402 flush_workqueue(dlm->dlm_worker);
403 destroy_workqueue(dlm->dlm_worker);
404 dlm->dlm_worker = NULL;
405 }
406 }
407
408 static void dlm_complete_dlm_shutdown(struct dlm_ctxt *dlm)
409 {
410 dlm_unregister_domain_handlers(dlm);
411 dlm_debug_shutdown(dlm);
412 dlm_complete_thread(dlm);
413 dlm_complete_recovery_thread(dlm);
414 dlm_destroy_dlm_worker(dlm);
415
416 /* We've left the domain. Now we can take ourselves out of the
417 * list and allow the kref stuff to help us free the
418 * memory. */
419 spin_lock(&dlm_domain_lock);
420 list_del_init(&dlm->list);
421 spin_unlock(&dlm_domain_lock);
422
423 /* Wake up anyone waiting for us to remove this domain */
424 wake_up(&dlm_domain_events);
425 }
426
427 static int dlm_migrate_all_locks(struct dlm_ctxt *dlm)
428 {
429 int i, num, n, ret = 0;
430 struct dlm_lock_resource *res;
431 struct hlist_node *iter;
432 struct hlist_head *bucket;
433 int dropped;
434
435 mlog(0, "Migrating locks from domain %s\n", dlm->name);
436
437 num = 0;
438 spin_lock(&dlm->spinlock);
439 for (i = 0; i < DLM_HASH_BUCKETS; i++) {
440 redo_bucket:
441 n = 0;
442 bucket = dlm_lockres_hash(dlm, i);
443 iter = bucket->first;
444 while (iter) {
445 n++;
446 res = hlist_entry(iter, struct dlm_lock_resource,
447 hash_node);
448 dlm_lockres_get(res);
449 /* migrate, if necessary. this will drop the dlm
450 * spinlock and retake it if it does migration. */
451 dropped = dlm_empty_lockres(dlm, res);
452
453 spin_lock(&res->spinlock);
454 if (dropped)
455 __dlm_lockres_calc_usage(dlm, res);
456 else
457 iter = res->hash_node.next;
458 spin_unlock(&res->spinlock);
459
460 dlm_lockres_put(res);
461
462 if (dropped) {
463 cond_resched_lock(&dlm->spinlock);
464 goto redo_bucket;
465 }
466 }
467 cond_resched_lock(&dlm->spinlock);
468 num += n;
469 }
470 spin_unlock(&dlm->spinlock);
471 wake_up(&dlm->dlm_thread_wq);
472
473 /* let the dlm thread take care of purging, keep scanning until
474 * nothing remains in the hash */
475 if (num) {
476 mlog(0, "%s: %d lock resources in hash last pass\n",
477 dlm->name, num);
478 ret = -EAGAIN;
479 }
480 mlog(0, "DONE Migrating locks from domain %s\n", dlm->name);
481 return ret;
482 }
483
484 static int dlm_no_joining_node(struct dlm_ctxt *dlm)
485 {
486 int ret;
487
488 spin_lock(&dlm->spinlock);
489 ret = dlm->joining_node == DLM_LOCK_RES_OWNER_UNKNOWN;
490 spin_unlock(&dlm->spinlock);
491
492 return ret;
493 }
494
495 static int dlm_begin_exit_domain_handler(struct o2net_msg *msg, u32 len,
496 void *data, void **ret_data)
497 {
498 struct dlm_ctxt *dlm = data;
499 unsigned int node;
500 struct dlm_exit_domain *exit_msg = (struct dlm_exit_domain *) msg->buf;
501
502 if (!dlm_grab(dlm))
503 return 0;
504
505 node = exit_msg->node_idx;
506 mlog(0, "%s: Node %u sent a begin exit domain message\n", dlm->name, node);
507
508 spin_lock(&dlm->spinlock);
509 set_bit(node, dlm->exit_domain_map);
510 spin_unlock(&dlm->spinlock);
511
512 dlm_put(dlm);
513
514 return 0;
515 }
516
517 static void dlm_mark_domain_leaving(struct dlm_ctxt *dlm)
518 {
519 /* Yikes, a double spinlock! I need domain_lock for the dlm
520 * state and the dlm spinlock for join state... Sorry! */
521 again:
522 spin_lock(&dlm_domain_lock);
523 spin_lock(&dlm->spinlock);
524
525 if (dlm->joining_node != DLM_LOCK_RES_OWNER_UNKNOWN) {
526 mlog(0, "Node %d is joining, we wait on it.\n",
527 dlm->joining_node);
528 spin_unlock(&dlm->spinlock);
529 spin_unlock(&dlm_domain_lock);
530
531 wait_event(dlm->dlm_join_events, dlm_no_joining_node(dlm));
532 goto again;
533 }
534
535 dlm->dlm_state = DLM_CTXT_LEAVING;
536 spin_unlock(&dlm->spinlock);
537 spin_unlock(&dlm_domain_lock);
538 }
539
540 static void __dlm_print_nodes(struct dlm_ctxt *dlm)
541 {
542 int node = -1;
543
544 assert_spin_locked(&dlm->spinlock);
545
546 printk(KERN_NOTICE "o2dlm: Nodes in domain %s: ", dlm->name);
547
548 while ((node = find_next_bit(dlm->domain_map, O2NM_MAX_NODES,
549 node + 1)) < O2NM_MAX_NODES) {
550 printk("%d ", node);
551 }
552 printk("\n");
553 }
554
555 static int dlm_exit_domain_handler(struct o2net_msg *msg, u32 len, void *data,
556 void **ret_data)
557 {
558 struct dlm_ctxt *dlm = data;
559 unsigned int node;
560 struct dlm_exit_domain *exit_msg = (struct dlm_exit_domain *) msg->buf;
561
562 mlog(0, "%p %u %p", msg, len, data);
563
564 if (!dlm_grab(dlm))
565 return 0;
566
567 node = exit_msg->node_idx;
568
569 printk(KERN_NOTICE "o2dlm: Node %u leaves domain %s\n", node, dlm->name);
570
571 spin_lock(&dlm->spinlock);
572 clear_bit(node, dlm->domain_map);
573 clear_bit(node, dlm->exit_domain_map);
574 __dlm_print_nodes(dlm);
575
576 /* notify anything attached to the heartbeat events */
577 dlm_hb_event_notify_attached(dlm, node, 0);
578
579 spin_unlock(&dlm->spinlock);
580
581 dlm_put(dlm);
582
583 return 0;
584 }
585
586 static int dlm_send_one_domain_exit(struct dlm_ctxt *dlm, u32 msg_type,
587 unsigned int node)
588 {
589 int status;
590 struct dlm_exit_domain leave_msg;
591
592 mlog(0, "%s: Sending domain exit message %u to node %u\n", dlm->name,
593 msg_type, node);
594
595 memset(&leave_msg, 0, sizeof(leave_msg));
596 leave_msg.node_idx = dlm->node_num;
597
598 status = o2net_send_message(msg_type, dlm->key, &leave_msg,
599 sizeof(leave_msg), node, NULL);
600 if (status < 0)
601 mlog(ML_ERROR, "Error %d sending domain exit message %u "
602 "to node %u on domain %s\n", status, msg_type, node,
603 dlm->name);
604
605 return status;
606 }
607
608 static void dlm_begin_exit_domain(struct dlm_ctxt *dlm)
609 {
610 int node = -1;
611
612 /* Support for begin exit domain was added in 1.2 */
613 if (dlm->dlm_locking_proto.pv_major == 1 &&
614 dlm->dlm_locking_proto.pv_minor < 2)
615 return;
616
617 /*
618 * Unlike DLM_EXIT_DOMAIN_MSG, DLM_BEGIN_EXIT_DOMAIN_MSG is purely
619 * informational. Meaning if a node does not receive the message,
620 * so be it.
621 */
622 spin_lock(&dlm->spinlock);
623 while (1) {
624 node = find_next_bit(dlm->domain_map, O2NM_MAX_NODES, node + 1);
625 if (node >= O2NM_MAX_NODES)
626 break;
627 if (node == dlm->node_num)
628 continue;
629
630 spin_unlock(&dlm->spinlock);
631 dlm_send_one_domain_exit(dlm, DLM_BEGIN_EXIT_DOMAIN_MSG, node);
632 spin_lock(&dlm->spinlock);
633 }
634 spin_unlock(&dlm->spinlock);
635 }
636
637 static void dlm_leave_domain(struct dlm_ctxt *dlm)
638 {
639 int node, clear_node, status;
640
641 /* At this point we've migrated away all our locks and won't
642 * accept mastership of new ones. The dlm is responsible for
643 * almost nothing now. We make sure not to confuse any joining
644 * nodes and then commence shutdown procedure. */
645
646 spin_lock(&dlm->spinlock);
647 /* Clear ourselves from the domain map */
648 clear_bit(dlm->node_num, dlm->domain_map);
649 while ((node = find_next_bit(dlm->domain_map, O2NM_MAX_NODES,
650 0)) < O2NM_MAX_NODES) {
651 /* Drop the dlm spinlock. This is safe wrt the domain_map.
652 * -nodes cannot be added now as the
653 * query_join_handlers knows to respond with OK_NO_MAP
654 * -we catch the right network errors if a node is
655 * removed from the map while we're sending him the
656 * exit message. */
657 spin_unlock(&dlm->spinlock);
658
659 clear_node = 1;
660
661 status = dlm_send_one_domain_exit(dlm, DLM_EXIT_DOMAIN_MSG,
662 node);
663 if (status < 0 &&
664 status != -ENOPROTOOPT &&
665 status != -ENOTCONN) {
666 mlog(ML_NOTICE, "Error %d sending domain exit message "
667 "to node %d\n", status, node);
668
669 /* Not sure what to do here but lets sleep for
670 * a bit in case this was a transient
671 * error... */
672 msleep(DLM_DOMAIN_BACKOFF_MS);
673 clear_node = 0;
674 }
675
676 spin_lock(&dlm->spinlock);
677 /* If we're not clearing the node bit then we intend
678 * to loop back around to try again. */
679 if (clear_node)
680 clear_bit(node, dlm->domain_map);
681 }
682 spin_unlock(&dlm->spinlock);
683 }
684
685 int dlm_joined(struct dlm_ctxt *dlm)
686 {
687 int ret = 0;
688
689 spin_lock(&dlm_domain_lock);
690
691 if (dlm->dlm_state == DLM_CTXT_JOINED)
692 ret = 1;
693
694 spin_unlock(&dlm_domain_lock);
695
696 return ret;
697 }
698
699 int dlm_shutting_down(struct dlm_ctxt *dlm)
700 {
701 int ret = 0;
702
703 spin_lock(&dlm_domain_lock);
704
705 if (dlm->dlm_state == DLM_CTXT_IN_SHUTDOWN)
706 ret = 1;
707
708 spin_unlock(&dlm_domain_lock);
709
710 return ret;
711 }
712
713 void dlm_unregister_domain(struct dlm_ctxt *dlm)
714 {
715 int leave = 0;
716 struct dlm_lock_resource *res;
717
718 spin_lock(&dlm_domain_lock);
719 BUG_ON(dlm->dlm_state != DLM_CTXT_JOINED);
720 BUG_ON(!dlm->num_joins);
721
722 dlm->num_joins--;
723 if (!dlm->num_joins) {
724 /* We mark it "in shutdown" now so new register
725 * requests wait until we've completely left the
726 * domain. Don't use DLM_CTXT_LEAVING yet as we still
727 * want new domain joins to communicate with us at
728 * least until we've completed migration of our
729 * resources. */
730 dlm->dlm_state = DLM_CTXT_IN_SHUTDOWN;
731 leave = 1;
732 }
733 spin_unlock(&dlm_domain_lock);
734
735 if (leave) {
736 mlog(0, "shutting down domain %s\n", dlm->name);
737 dlm_begin_exit_domain(dlm);
738
739 /* We changed dlm state, notify the thread */
740 dlm_kick_thread(dlm, NULL);
741
742 while (dlm_migrate_all_locks(dlm)) {
743 /* Give dlm_thread time to purge the lockres' */
744 msleep(500);
745 mlog(0, "%s: more migration to do\n", dlm->name);
746 }
747
748 /* This list should be empty. If not, print remaining lockres */
749 if (!list_empty(&dlm->tracking_list)) {
750 mlog(ML_ERROR, "Following lockres' are still on the "
751 "tracking list:\n");
752 list_for_each_entry(res, &dlm->tracking_list, tracking)
753 dlm_print_one_lock_resource(res);
754 }
755
756 dlm_mark_domain_leaving(dlm);
757 dlm_leave_domain(dlm);
758 dlm_force_free_mles(dlm);
759 dlm_complete_dlm_shutdown(dlm);
760 }
761 dlm_put(dlm);
762 }
763 EXPORT_SYMBOL_GPL(dlm_unregister_domain);
764
765 static int dlm_query_join_proto_check(char *proto_type, int node,
766 struct dlm_protocol_version *ours,
767 struct dlm_protocol_version *request)
768 {
769 int rc;
770 struct dlm_protocol_version proto = *request;
771
772 if (!dlm_protocol_compare(ours, &proto)) {
773 mlog(0,
774 "node %u wanted to join with %s locking protocol "
775 "%u.%u, we respond with %u.%u\n",
776 node, proto_type,
777 request->pv_major,
778 request->pv_minor,
779 proto.pv_major, proto.pv_minor);
780 request->pv_minor = proto.pv_minor;
781 rc = 0;
782 } else {
783 mlog(ML_NOTICE,
784 "Node %u wanted to join with %s locking "
785 "protocol %u.%u, but we have %u.%u, disallowing\n",
786 node, proto_type,
787 request->pv_major,
788 request->pv_minor,
789 ours->pv_major,
790 ours->pv_minor);
791 rc = 1;
792 }
793
794 return rc;
795 }
796
797 /*
798 * struct dlm_query_join_packet is made up of four one-byte fields. They
799 * are effectively in big-endian order already. However, little-endian
800 * machines swap them before putting the packet on the wire (because
801 * query_join's response is a status, and that status is treated as a u32
802 * on the wire). Thus, a big-endian and little-endian machines will treat
803 * this structure differently.
804 *
805 * The solution is to have little-endian machines swap the structure when
806 * converting from the structure to the u32 representation. This will
807 * result in the structure having the correct format on the wire no matter
808 * the host endian format.
809 */
810 static void dlm_query_join_packet_to_wire(struct dlm_query_join_packet *packet,
811 u32 *wire)
812 {
813 union dlm_query_join_response response;
814
815 response.packet = *packet;
816 *wire = cpu_to_be32(response.intval);
817 }
818
819 static void dlm_query_join_wire_to_packet(u32 wire,
820 struct dlm_query_join_packet *packet)
821 {
822 union dlm_query_join_response response;
823
824 response.intval = cpu_to_be32(wire);
825 *packet = response.packet;
826 }
827
828 static int dlm_query_join_handler(struct o2net_msg *msg, u32 len, void *data,
829 void **ret_data)
830 {
831 struct dlm_query_join_request *query;
832 struct dlm_query_join_packet packet = {
833 .code = JOIN_DISALLOW,
834 };
835 struct dlm_ctxt *dlm = NULL;
836 u32 response;
837 u8 nodenum;
838
839 query = (struct dlm_query_join_request *) msg->buf;
840
841 mlog(0, "node %u wants to join domain %s\n", query->node_idx,
842 query->domain);
843
844 /*
845 * If heartbeat doesn't consider the node live, tell it
846 * to back off and try again. This gives heartbeat a chance
847 * to catch up.
848 */
849 if (!o2hb_check_node_heartbeating(query->node_idx)) {
850 mlog(0, "node %u is not in our live map yet\n",
851 query->node_idx);
852
853 packet.code = JOIN_DISALLOW;
854 goto respond;
855 }
856
857 packet.code = JOIN_OK_NO_MAP;
858
859 spin_lock(&dlm_domain_lock);
860 dlm = __dlm_lookup_domain_full(query->domain, query->name_len);
861 if (!dlm)
862 goto unlock_respond;
863
864 /*
865 * There is a small window where the joining node may not see the
866 * node(s) that just left but still part of the cluster. DISALLOW
867 * join request if joining node has different node map.
868 */
869 nodenum=0;
870 while (nodenum < O2NM_MAX_NODES) {
871 if (test_bit(nodenum, dlm->domain_map)) {
872 if (!byte_test_bit(nodenum, query->node_map)) {
873 mlog(0, "disallow join as node %u does not "
874 "have node %u in its nodemap\n",
875 query->node_idx, nodenum);
876 packet.code = JOIN_DISALLOW;
877 goto unlock_respond;
878 }
879 }
880 nodenum++;
881 }
882
883 /* Once the dlm ctxt is marked as leaving then we don't want
884 * to be put in someone's domain map.
885 * Also, explicitly disallow joining at certain troublesome
886 * times (ie. during recovery). */
887 if (dlm && dlm->dlm_state != DLM_CTXT_LEAVING) {
888 int bit = query->node_idx;
889 spin_lock(&dlm->spinlock);
890
891 if (dlm->dlm_state == DLM_CTXT_NEW &&
892 dlm->joining_node == DLM_LOCK_RES_OWNER_UNKNOWN) {
893 /*If this is a brand new context and we
894 * haven't started our join process yet, then
895 * the other node won the race. */
896 packet.code = JOIN_OK_NO_MAP;
897 } else if (dlm->joining_node != DLM_LOCK_RES_OWNER_UNKNOWN) {
898 /* Disallow parallel joins. */
899 packet.code = JOIN_DISALLOW;
900 } else if (dlm->reco.state & DLM_RECO_STATE_ACTIVE) {
901 mlog(0, "node %u trying to join, but recovery "
902 "is ongoing.\n", bit);
903 packet.code = JOIN_DISALLOW;
904 } else if (test_bit(bit, dlm->recovery_map)) {
905 mlog(0, "node %u trying to join, but it "
906 "still needs recovery.\n", bit);
907 packet.code = JOIN_DISALLOW;
908 } else if (test_bit(bit, dlm->domain_map)) {
909 mlog(0, "node %u trying to join, but it "
910 "is still in the domain! needs recovery?\n",
911 bit);
912 packet.code = JOIN_DISALLOW;
913 } else {
914 /* Alright we're fully a part of this domain
915 * so we keep some state as to who's joining
916 * and indicate to him that needs to be fixed
917 * up. */
918
919 /* Make sure we speak compatible locking protocols. */
920 if (dlm_query_join_proto_check("DLM", bit,
921 &dlm->dlm_locking_proto,
922 &query->dlm_proto)) {
923 packet.code = JOIN_PROTOCOL_MISMATCH;
924 } else if (dlm_query_join_proto_check("fs", bit,
925 &dlm->fs_locking_proto,
926 &query->fs_proto)) {
927 packet.code = JOIN_PROTOCOL_MISMATCH;
928 } else {
929 packet.dlm_minor = query->dlm_proto.pv_minor;
930 packet.fs_minor = query->fs_proto.pv_minor;
931 packet.code = JOIN_OK;
932 __dlm_set_joining_node(dlm, query->node_idx);
933 }
934 }
935
936 spin_unlock(&dlm->spinlock);
937 }
938 unlock_respond:
939 spin_unlock(&dlm_domain_lock);
940
941 respond:
942 mlog(0, "We respond with %u\n", packet.code);
943
944 dlm_query_join_packet_to_wire(&packet, &response);
945 return response;
946 }
947
948 static int dlm_assert_joined_handler(struct o2net_msg *msg, u32 len, void *data,
949 void **ret_data)
950 {
951 struct dlm_assert_joined *assert;
952 struct dlm_ctxt *dlm = NULL;
953
954 assert = (struct dlm_assert_joined *) msg->buf;
955
956 mlog(0, "node %u asserts join on domain %s\n", assert->node_idx,
957 assert->domain);
958
959 spin_lock(&dlm_domain_lock);
960 dlm = __dlm_lookup_domain_full(assert->domain, assert->name_len);
961 /* XXX should we consider no dlm ctxt an error? */
962 if (dlm) {
963 spin_lock(&dlm->spinlock);
964
965 /* Alright, this node has officially joined our
966 * domain. Set him in the map and clean up our
967 * leftover join state. */
968 BUG_ON(dlm->joining_node != assert->node_idx);
969 set_bit(assert->node_idx, dlm->domain_map);
970 clear_bit(assert->node_idx, dlm->exit_domain_map);
971 __dlm_set_joining_node(dlm, DLM_LOCK_RES_OWNER_UNKNOWN);
972
973 printk(KERN_NOTICE "o2dlm: Node %u joins domain %s\n",
974 assert->node_idx, dlm->name);
975 __dlm_print_nodes(dlm);
976
977 /* notify anything attached to the heartbeat events */
978 dlm_hb_event_notify_attached(dlm, assert->node_idx, 1);
979
980 spin_unlock(&dlm->spinlock);
981 }
982 spin_unlock(&dlm_domain_lock);
983
984 return 0;
985 }
986
987 static int dlm_match_regions(struct dlm_ctxt *dlm,
988 struct dlm_query_region *qr,
989 char *local, int locallen)
990 {
991 char *remote = qr->qr_regions;
992 char *l, *r;
993 int localnr, i, j, foundit;
994 int status = 0;
995
996 if (!o2hb_global_heartbeat_active()) {
997 if (qr->qr_numregions) {
998 mlog(ML_ERROR, "Domain %s: Joining node %d has global "
999 "heartbeat enabled but local node %d does not\n",
1000 qr->qr_domain, qr->qr_node, dlm->node_num);
1001 status = -EINVAL;
1002 }
1003 goto bail;
1004 }
1005
1006 if (o2hb_global_heartbeat_active() && !qr->qr_numregions) {
1007 mlog(ML_ERROR, "Domain %s: Local node %d has global "
1008 "heartbeat enabled but joining node %d does not\n",
1009 qr->qr_domain, dlm->node_num, qr->qr_node);
1010 status = -EINVAL;
1011 goto bail;
1012 }
1013
1014 r = remote;
1015 for (i = 0; i < qr->qr_numregions; ++i) {
1016 mlog(0, "Region %.*s\n", O2HB_MAX_REGION_NAME_LEN, r);
1017 r += O2HB_MAX_REGION_NAME_LEN;
1018 }
1019
1020 localnr = min(O2NM_MAX_REGIONS, locallen/O2HB_MAX_REGION_NAME_LEN);
1021 localnr = o2hb_get_all_regions(local, (u8)localnr);
1022
1023 /* compare local regions with remote */
1024 l = local;
1025 for (i = 0; i < localnr; ++i) {
1026 foundit = 0;
1027 r = remote;
1028 for (j = 0; j <= qr->qr_numregions; ++j) {
1029 if (!memcmp(l, r, O2HB_MAX_REGION_NAME_LEN)) {
1030 foundit = 1;
1031 break;
1032 }
1033 r += O2HB_MAX_REGION_NAME_LEN;
1034 }
1035 if (!foundit) {
1036 status = -EINVAL;
1037 mlog(ML_ERROR, "Domain %s: Region '%.*s' registered "
1038 "in local node %d but not in joining node %d\n",
1039 qr->qr_domain, O2HB_MAX_REGION_NAME_LEN, l,
1040 dlm->node_num, qr->qr_node);
1041 goto bail;
1042 }
1043 l += O2HB_MAX_REGION_NAME_LEN;
1044 }
1045
1046 /* compare remote with local regions */
1047 r = remote;
1048 for (i = 0; i < qr->qr_numregions; ++i) {
1049 foundit = 0;
1050 l = local;
1051 for (j = 0; j < localnr; ++j) {
1052 if (!memcmp(r, l, O2HB_MAX_REGION_NAME_LEN)) {
1053 foundit = 1;
1054 break;
1055 }
1056 l += O2HB_MAX_REGION_NAME_LEN;
1057 }
1058 if (!foundit) {
1059 status = -EINVAL;
1060 mlog(ML_ERROR, "Domain %s: Region '%.*s' registered "
1061 "in joining node %d but not in local node %d\n",
1062 qr->qr_domain, O2HB_MAX_REGION_NAME_LEN, r,
1063 qr->qr_node, dlm->node_num);
1064 goto bail;
1065 }
1066 r += O2HB_MAX_REGION_NAME_LEN;
1067 }
1068
1069 bail:
1070 return status;
1071 }
1072
1073 static int dlm_send_regions(struct dlm_ctxt *dlm, unsigned long *node_map)
1074 {
1075 struct dlm_query_region *qr = NULL;
1076 int status, ret = 0, i;
1077 char *p;
1078
1079 if (find_next_bit(node_map, O2NM_MAX_NODES, 0) >= O2NM_MAX_NODES)
1080 goto bail;
1081
1082 qr = kzalloc(sizeof(struct dlm_query_region), GFP_KERNEL);
1083 if (!qr) {
1084 ret = -ENOMEM;
1085 mlog_errno(ret);
1086 goto bail;
1087 }
1088
1089 qr->qr_node = dlm->node_num;
1090 qr->qr_namelen = strlen(dlm->name);
1091 memcpy(qr->qr_domain, dlm->name, qr->qr_namelen);
1092 /* if local hb, the numregions will be zero */
1093 if (o2hb_global_heartbeat_active())
1094 qr->qr_numregions = o2hb_get_all_regions(qr->qr_regions,
1095 O2NM_MAX_REGIONS);
1096
1097 p = qr->qr_regions;
1098 for (i = 0; i < qr->qr_numregions; ++i, p += O2HB_MAX_REGION_NAME_LEN)
1099 mlog(0, "Region %.*s\n", O2HB_MAX_REGION_NAME_LEN, p);
1100
1101 i = -1;
1102 while ((i = find_next_bit(node_map, O2NM_MAX_NODES,
1103 i + 1)) < O2NM_MAX_NODES) {
1104 if (i == dlm->node_num)
1105 continue;
1106
1107 mlog(0, "Sending regions to node %d\n", i);
1108
1109 ret = o2net_send_message(DLM_QUERY_REGION, DLM_MOD_KEY, qr,
1110 sizeof(struct dlm_query_region),
1111 i, &status);
1112 if (ret >= 0)
1113 ret = status;
1114 if (ret) {
1115 mlog(ML_ERROR, "Region mismatch %d, node %d\n",
1116 ret, i);
1117 break;
1118 }
1119 }
1120
1121 bail:
1122 kfree(qr);
1123 return ret;
1124 }
1125
1126 static int dlm_query_region_handler(struct o2net_msg *msg, u32 len,
1127 void *data, void **ret_data)
1128 {
1129 struct dlm_query_region *qr;
1130 struct dlm_ctxt *dlm = NULL;
1131 char *local = NULL;
1132 int status = 0;
1133 int locked = 0;
1134
1135 qr = (struct dlm_query_region *) msg->buf;
1136
1137 mlog(0, "Node %u queries hb regions on domain %s\n", qr->qr_node,
1138 qr->qr_domain);
1139
1140 /* buffer used in dlm_mast_regions() */
1141 local = kmalloc(sizeof(qr->qr_regions), GFP_KERNEL);
1142 if (!local) {
1143 status = -ENOMEM;
1144 goto bail;
1145 }
1146
1147 status = -EINVAL;
1148
1149 spin_lock(&dlm_domain_lock);
1150 dlm = __dlm_lookup_domain_full(qr->qr_domain, qr->qr_namelen);
1151 if (!dlm) {
1152 mlog(ML_ERROR, "Node %d queried hb regions on domain %s "
1153 "before join domain\n", qr->qr_node, qr->qr_domain);
1154 goto bail;
1155 }
1156
1157 spin_lock(&dlm->spinlock);
1158 locked = 1;
1159 if (dlm->joining_node != qr->qr_node) {
1160 mlog(ML_ERROR, "Node %d queried hb regions on domain %s "
1161 "but joining node is %d\n", qr->qr_node, qr->qr_domain,
1162 dlm->joining_node);
1163 goto bail;
1164 }
1165
1166 /* Support for global heartbeat was added in 1.1 */
1167 if (dlm->dlm_locking_proto.pv_major == 1 &&
1168 dlm->dlm_locking_proto.pv_minor == 0) {
1169 mlog(ML_ERROR, "Node %d queried hb regions on domain %s "
1170 "but active dlm protocol is %d.%d\n", qr->qr_node,
1171 qr->qr_domain, dlm->dlm_locking_proto.pv_major,
1172 dlm->dlm_locking_proto.pv_minor);
1173 goto bail;
1174 }
1175
1176 status = dlm_match_regions(dlm, qr, local, sizeof(qr->qr_regions));
1177
1178 bail:
1179 if (locked)
1180 spin_unlock(&dlm->spinlock);
1181 spin_unlock(&dlm_domain_lock);
1182
1183 kfree(local);
1184
1185 return status;
1186 }
1187
1188 static int dlm_match_nodes(struct dlm_ctxt *dlm, struct dlm_query_nodeinfo *qn)
1189 {
1190 struct o2nm_node *local;
1191 struct dlm_node_info *remote;
1192 int i, j;
1193 int status = 0;
1194
1195 for (j = 0; j < qn->qn_numnodes; ++j)
1196 mlog(0, "Node %3d, %pI4:%u\n", qn->qn_nodes[j].ni_nodenum,
1197 &(qn->qn_nodes[j].ni_ipv4_address),
1198 ntohs(qn->qn_nodes[j].ni_ipv4_port));
1199
1200 for (i = 0; i < O2NM_MAX_NODES && !status; ++i) {
1201 local = o2nm_get_node_by_num(i);
1202 remote = NULL;
1203 for (j = 0; j < qn->qn_numnodes; ++j) {
1204 if (qn->qn_nodes[j].ni_nodenum == i) {
1205 remote = &(qn->qn_nodes[j]);
1206 break;
1207 }
1208 }
1209
1210 if (!local && !remote)
1211 continue;
1212
1213 if ((local && !remote) || (!local && remote))
1214 status = -EINVAL;
1215
1216 if (!status &&
1217 ((remote->ni_nodenum != local->nd_num) ||
1218 (remote->ni_ipv4_port != local->nd_ipv4_port) ||
1219 (remote->ni_ipv4_address != local->nd_ipv4_address)))
1220 status = -EINVAL;
1221
1222 if (status) {
1223 if (remote && !local)
1224 mlog(ML_ERROR, "Domain %s: Node %d (%pI4:%u) "
1225 "registered in joining node %d but not in "
1226 "local node %d\n", qn->qn_domain,
1227 remote->ni_nodenum,
1228 &(remote->ni_ipv4_address),
1229 ntohs(remote->ni_ipv4_port),
1230 qn->qn_nodenum, dlm->node_num);
1231 if (local && !remote)
1232 mlog(ML_ERROR, "Domain %s: Node %d (%pI4:%u) "
1233 "registered in local node %d but not in "
1234 "joining node %d\n", qn->qn_domain,
1235 local->nd_num, &(local->nd_ipv4_address),
1236 ntohs(local->nd_ipv4_port),
1237 dlm->node_num, qn->qn_nodenum);
1238 BUG_ON((!local && !remote));
1239 }
1240
1241 if (local)
1242 o2nm_node_put(local);
1243 }
1244
1245 return status;
1246 }
1247
1248 static int dlm_send_nodeinfo(struct dlm_ctxt *dlm, unsigned long *node_map)
1249 {
1250 struct dlm_query_nodeinfo *qn = NULL;
1251 struct o2nm_node *node;
1252 int ret = 0, status, count, i;
1253
1254 if (find_next_bit(node_map, O2NM_MAX_NODES, 0) >= O2NM_MAX_NODES)
1255 goto bail;
1256
1257 qn = kzalloc(sizeof(struct dlm_query_nodeinfo), GFP_KERNEL);
1258 if (!qn) {
1259 ret = -ENOMEM;
1260 mlog_errno(ret);
1261 goto bail;
1262 }
1263
1264 for (i = 0, count = 0; i < O2NM_MAX_NODES; ++i) {
1265 node = o2nm_get_node_by_num(i);
1266 if (!node)
1267 continue;
1268 qn->qn_nodes[count].ni_nodenum = node->nd_num;
1269 qn->qn_nodes[count].ni_ipv4_port = node->nd_ipv4_port;
1270 qn->qn_nodes[count].ni_ipv4_address = node->nd_ipv4_address;
1271 mlog(0, "Node %3d, %pI4:%u\n", node->nd_num,
1272 &(node->nd_ipv4_address), ntohs(node->nd_ipv4_port));
1273 ++count;
1274 o2nm_node_put(node);
1275 }
1276
1277 qn->qn_nodenum = dlm->node_num;
1278 qn->qn_numnodes = count;
1279 qn->qn_namelen = strlen(dlm->name);
1280 memcpy(qn->qn_domain, dlm->name, qn->qn_namelen);
1281
1282 i = -1;
1283 while ((i = find_next_bit(node_map, O2NM_MAX_NODES,
1284 i + 1)) < O2NM_MAX_NODES) {
1285 if (i == dlm->node_num)
1286 continue;
1287
1288 mlog(0, "Sending nodeinfo to node %d\n", i);
1289
1290 ret = o2net_send_message(DLM_QUERY_NODEINFO, DLM_MOD_KEY,
1291 qn, sizeof(struct dlm_query_nodeinfo),
1292 i, &status);
1293 if (ret >= 0)
1294 ret = status;
1295 if (ret) {
1296 mlog(ML_ERROR, "node mismatch %d, node %d\n", ret, i);
1297 break;
1298 }
1299 }
1300
1301 bail:
1302 kfree(qn);
1303 return ret;
1304 }
1305
1306 static int dlm_query_nodeinfo_handler(struct o2net_msg *msg, u32 len,
1307 void *data, void **ret_data)
1308 {
1309 struct dlm_query_nodeinfo *qn;
1310 struct dlm_ctxt *dlm = NULL;
1311 int locked = 0, status = -EINVAL;
1312
1313 qn = (struct dlm_query_nodeinfo *) msg->buf;
1314
1315 mlog(0, "Node %u queries nodes on domain %s\n", qn->qn_nodenum,
1316 qn->qn_domain);
1317
1318 spin_lock(&dlm_domain_lock);
1319 dlm = __dlm_lookup_domain_full(qn->qn_domain, qn->qn_namelen);
1320 if (!dlm) {
1321 mlog(ML_ERROR, "Node %d queried nodes on domain %s before "
1322 "join domain\n", qn->qn_nodenum, qn->qn_domain);
1323 goto bail;
1324 }
1325
1326 spin_lock(&dlm->spinlock);
1327 locked = 1;
1328 if (dlm->joining_node != qn->qn_nodenum) {
1329 mlog(ML_ERROR, "Node %d queried nodes on domain %s but "
1330 "joining node is %d\n", qn->qn_nodenum, qn->qn_domain,
1331 dlm->joining_node);
1332 goto bail;
1333 }
1334
1335 /* Support for node query was added in 1.1 */
1336 if (dlm->dlm_locking_proto.pv_major == 1 &&
1337 dlm->dlm_locking_proto.pv_minor == 0) {
1338 mlog(ML_ERROR, "Node %d queried nodes on domain %s "
1339 "but active dlm protocol is %d.%d\n", qn->qn_nodenum,
1340 qn->qn_domain, dlm->dlm_locking_proto.pv_major,
1341 dlm->dlm_locking_proto.pv_minor);
1342 goto bail;
1343 }
1344
1345 status = dlm_match_nodes(dlm, qn);
1346
1347 bail:
1348 if (locked)
1349 spin_unlock(&dlm->spinlock);
1350 spin_unlock(&dlm_domain_lock);
1351
1352 return status;
1353 }
1354
1355 static int dlm_cancel_join_handler(struct o2net_msg *msg, u32 len, void *data,
1356 void **ret_data)
1357 {
1358 struct dlm_cancel_join *cancel;
1359 struct dlm_ctxt *dlm = NULL;
1360
1361 cancel = (struct dlm_cancel_join *) msg->buf;
1362
1363 mlog(0, "node %u cancels join on domain %s\n", cancel->node_idx,
1364 cancel->domain);
1365
1366 spin_lock(&dlm_domain_lock);
1367 dlm = __dlm_lookup_domain_full(cancel->domain, cancel->name_len);
1368
1369 if (dlm) {
1370 spin_lock(&dlm->spinlock);
1371
1372 /* Yikes, this guy wants to cancel his join. No
1373 * problem, we simply cleanup our join state. */
1374 BUG_ON(dlm->joining_node != cancel->node_idx);
1375 __dlm_set_joining_node(dlm, DLM_LOCK_RES_OWNER_UNKNOWN);
1376
1377 spin_unlock(&dlm->spinlock);
1378 }
1379 spin_unlock(&dlm_domain_lock);
1380
1381 return 0;
1382 }
1383
1384 static int dlm_send_one_join_cancel(struct dlm_ctxt *dlm,
1385 unsigned int node)
1386 {
1387 int status;
1388 struct dlm_cancel_join cancel_msg;
1389
1390 memset(&cancel_msg, 0, sizeof(cancel_msg));
1391 cancel_msg.node_idx = dlm->node_num;
1392 cancel_msg.name_len = strlen(dlm->name);
1393 memcpy(cancel_msg.domain, dlm->name, cancel_msg.name_len);
1394
1395 status = o2net_send_message(DLM_CANCEL_JOIN_MSG, DLM_MOD_KEY,
1396 &cancel_msg, sizeof(cancel_msg), node,
1397 NULL);
1398 if (status < 0) {
1399 mlog(ML_ERROR, "Error %d when sending message %u (key 0x%x) to "
1400 "node %u\n", status, DLM_CANCEL_JOIN_MSG, DLM_MOD_KEY,
1401 node);
1402 goto bail;
1403 }
1404
1405 bail:
1406 return status;
1407 }
1408
1409 /* map_size should be in bytes. */
1410 static int dlm_send_join_cancels(struct dlm_ctxt *dlm,
1411 unsigned long *node_map,
1412 unsigned int map_size)
1413 {
1414 int status, tmpstat;
1415 unsigned int node;
1416
1417 if (map_size != (BITS_TO_LONGS(O2NM_MAX_NODES) *
1418 sizeof(unsigned long))) {
1419 mlog(ML_ERROR,
1420 "map_size %u != BITS_TO_LONGS(O2NM_MAX_NODES) %u\n",
1421 map_size, (unsigned)BITS_TO_LONGS(O2NM_MAX_NODES));
1422 return -EINVAL;
1423 }
1424
1425 status = 0;
1426 node = -1;
1427 while ((node = find_next_bit(node_map, O2NM_MAX_NODES,
1428 node + 1)) < O2NM_MAX_NODES) {
1429 if (node == dlm->node_num)
1430 continue;
1431
1432 tmpstat = dlm_send_one_join_cancel(dlm, node);
1433 if (tmpstat) {
1434 mlog(ML_ERROR, "Error return %d cancelling join on "
1435 "node %d\n", tmpstat, node);
1436 if (!status)
1437 status = tmpstat;
1438 }
1439 }
1440
1441 if (status)
1442 mlog_errno(status);
1443 return status;
1444 }
1445
1446 static int dlm_request_join(struct dlm_ctxt *dlm,
1447 int node,
1448 enum dlm_query_join_response_code *response)
1449 {
1450 int status;
1451 struct dlm_query_join_request join_msg;
1452 struct dlm_query_join_packet packet;
1453 u32 join_resp;
1454
1455 mlog(0, "querying node %d\n", node);
1456
1457 memset(&join_msg, 0, sizeof(join_msg));
1458 join_msg.node_idx = dlm->node_num;
1459 join_msg.name_len = strlen(dlm->name);
1460 memcpy(join_msg.domain, dlm->name, join_msg.name_len);
1461 join_msg.dlm_proto = dlm->dlm_locking_proto;
1462 join_msg.fs_proto = dlm->fs_locking_proto;
1463
1464 /* copy live node map to join message */
1465 byte_copymap(join_msg.node_map, dlm->live_nodes_map, O2NM_MAX_NODES);
1466
1467 status = o2net_send_message(DLM_QUERY_JOIN_MSG, DLM_MOD_KEY, &join_msg,
1468 sizeof(join_msg), node, &join_resp);
1469 if (status < 0 && status != -ENOPROTOOPT) {
1470 mlog(ML_ERROR, "Error %d when sending message %u (key 0x%x) to "
1471 "node %u\n", status, DLM_QUERY_JOIN_MSG, DLM_MOD_KEY,
1472 node);
1473 goto bail;
1474 }
1475 dlm_query_join_wire_to_packet(join_resp, &packet);
1476
1477 /* -ENOPROTOOPT from the net code means the other side isn't
1478 listening for our message type -- that's fine, it means
1479 his dlm isn't up, so we can consider him a 'yes' but not
1480 joined into the domain. */
1481 if (status == -ENOPROTOOPT) {
1482 status = 0;
1483 *response = JOIN_OK_NO_MAP;
1484 } else if (packet.code == JOIN_DISALLOW ||
1485 packet.code == JOIN_OK_NO_MAP) {
1486 *response = packet.code;
1487 } else if (packet.code == JOIN_PROTOCOL_MISMATCH) {
1488 mlog(ML_NOTICE,
1489 "This node requested DLM locking protocol %u.%u and "
1490 "filesystem locking protocol %u.%u. At least one of "
1491 "the protocol versions on node %d is not compatible, "
1492 "disconnecting\n",
1493 dlm->dlm_locking_proto.pv_major,
1494 dlm->dlm_locking_proto.pv_minor,
1495 dlm->fs_locking_proto.pv_major,
1496 dlm->fs_locking_proto.pv_minor,
1497 node);
1498 status = -EPROTO;
1499 *response = packet.code;
1500 } else if (packet.code == JOIN_OK) {
1501 *response = packet.code;
1502 /* Use the same locking protocol as the remote node */
1503 dlm->dlm_locking_proto.pv_minor = packet.dlm_minor;
1504 dlm->fs_locking_proto.pv_minor = packet.fs_minor;
1505 mlog(0,
1506 "Node %d responds JOIN_OK with DLM locking protocol "
1507 "%u.%u and fs locking protocol %u.%u\n",
1508 node,
1509 dlm->dlm_locking_proto.pv_major,
1510 dlm->dlm_locking_proto.pv_minor,
1511 dlm->fs_locking_proto.pv_major,
1512 dlm->fs_locking_proto.pv_minor);
1513 } else {
1514 status = -EINVAL;
1515 mlog(ML_ERROR, "invalid response %d from node %u\n",
1516 packet.code, node);
1517 }
1518
1519 mlog(0, "status %d, node %d response is %d\n", status, node,
1520 *response);
1521
1522 bail:
1523 return status;
1524 }
1525
1526 static int dlm_send_one_join_assert(struct dlm_ctxt *dlm,
1527 unsigned int node)
1528 {
1529 int status;
1530 struct dlm_assert_joined assert_msg;
1531
1532 mlog(0, "Sending join assert to node %u\n", node);
1533
1534 memset(&assert_msg, 0, sizeof(assert_msg));
1535 assert_msg.node_idx = dlm->node_num;
1536 assert_msg.name_len = strlen(dlm->name);
1537 memcpy(assert_msg.domain, dlm->name, assert_msg.name_len);
1538
1539 status = o2net_send_message(DLM_ASSERT_JOINED_MSG, DLM_MOD_KEY,
1540 &assert_msg, sizeof(assert_msg), node,
1541 NULL);
1542 if (status < 0)
1543 mlog(ML_ERROR, "Error %d when sending message %u (key 0x%x) to "
1544 "node %u\n", status, DLM_ASSERT_JOINED_MSG, DLM_MOD_KEY,
1545 node);
1546
1547 return status;
1548 }
1549
1550 static void dlm_send_join_asserts(struct dlm_ctxt *dlm,
1551 unsigned long *node_map)
1552 {
1553 int status, node, live;
1554
1555 status = 0;
1556 node = -1;
1557 while ((node = find_next_bit(node_map, O2NM_MAX_NODES,
1558 node + 1)) < O2NM_MAX_NODES) {
1559 if (node == dlm->node_num)
1560 continue;
1561
1562 do {
1563 /* It is very important that this message be
1564 * received so we spin until either the node
1565 * has died or it gets the message. */
1566 status = dlm_send_one_join_assert(dlm, node);
1567
1568 spin_lock(&dlm->spinlock);
1569 live = test_bit(node, dlm->live_nodes_map);
1570 spin_unlock(&dlm->spinlock);
1571
1572 if (status) {
1573 mlog(ML_ERROR, "Error return %d asserting "
1574 "join on node %d\n", status, node);
1575
1576 /* give us some time between errors... */
1577 if (live)
1578 msleep(DLM_DOMAIN_BACKOFF_MS);
1579 }
1580 } while (status && live);
1581 }
1582 }
1583
1584 struct domain_join_ctxt {
1585 unsigned long live_map[BITS_TO_LONGS(O2NM_MAX_NODES)];
1586 unsigned long yes_resp_map[BITS_TO_LONGS(O2NM_MAX_NODES)];
1587 };
1588
1589 static int dlm_should_restart_join(struct dlm_ctxt *dlm,
1590 struct domain_join_ctxt *ctxt,
1591 enum dlm_query_join_response_code response)
1592 {
1593 int ret;
1594
1595 if (response == JOIN_DISALLOW) {
1596 mlog(0, "Latest response of disallow -- should restart\n");
1597 return 1;
1598 }
1599
1600 spin_lock(&dlm->spinlock);
1601 /* For now, we restart the process if the node maps have
1602 * changed at all */
1603 ret = memcmp(ctxt->live_map, dlm->live_nodes_map,
1604 sizeof(dlm->live_nodes_map));
1605 spin_unlock(&dlm->spinlock);
1606
1607 if (ret)
1608 mlog(0, "Node maps changed -- should restart\n");
1609
1610 return ret;
1611 }
1612
1613 static int dlm_try_to_join_domain(struct dlm_ctxt *dlm)
1614 {
1615 int status = 0, tmpstat, node;
1616 struct domain_join_ctxt *ctxt;
1617 enum dlm_query_join_response_code response = JOIN_DISALLOW;
1618
1619 mlog(0, "%p", dlm);
1620
1621 ctxt = kzalloc(sizeof(*ctxt), GFP_KERNEL);
1622 if (!ctxt) {
1623 status = -ENOMEM;
1624 mlog_errno(status);
1625 goto bail;
1626 }
1627
1628 /* group sem locking should work for us here -- we're already
1629 * registered for heartbeat events so filling this should be
1630 * atomic wrt getting those handlers called. */
1631 o2hb_fill_node_map(dlm->live_nodes_map, sizeof(dlm->live_nodes_map));
1632
1633 spin_lock(&dlm->spinlock);
1634 memcpy(ctxt->live_map, dlm->live_nodes_map, sizeof(ctxt->live_map));
1635
1636 __dlm_set_joining_node(dlm, dlm->node_num);
1637
1638 spin_unlock(&dlm->spinlock);
1639
1640 node = -1;
1641 while ((node = find_next_bit(ctxt->live_map, O2NM_MAX_NODES,
1642 node + 1)) < O2NM_MAX_NODES) {
1643 if (node == dlm->node_num)
1644 continue;
1645
1646 status = dlm_request_join(dlm, node, &response);
1647 if (status < 0) {
1648 mlog_errno(status);
1649 goto bail;
1650 }
1651
1652 /* Ok, either we got a response or the node doesn't have a
1653 * dlm up. */
1654 if (response == JOIN_OK)
1655 set_bit(node, ctxt->yes_resp_map);
1656
1657 if (dlm_should_restart_join(dlm, ctxt, response)) {
1658 status = -EAGAIN;
1659 goto bail;
1660 }
1661 }
1662
1663 mlog(0, "Yay, done querying nodes!\n");
1664
1665 /* Yay, everyone agree's we can join the domain. My domain is
1666 * comprised of all nodes who were put in the
1667 * yes_resp_map. Copy that into our domain map and send a join
1668 * assert message to clean up everyone elses state. */
1669 spin_lock(&dlm->spinlock);
1670 memcpy(dlm->domain_map, ctxt->yes_resp_map,
1671 sizeof(ctxt->yes_resp_map));
1672 set_bit(dlm->node_num, dlm->domain_map);
1673 spin_unlock(&dlm->spinlock);
1674
1675 /* Support for global heartbeat and node info was added in 1.1 */
1676 if (dlm->dlm_locking_proto.pv_major > 1 ||
1677 dlm->dlm_locking_proto.pv_minor > 0) {
1678 status = dlm_send_nodeinfo(dlm, ctxt->yes_resp_map);
1679 if (status) {
1680 mlog_errno(status);
1681 goto bail;
1682 }
1683 status = dlm_send_regions(dlm, ctxt->yes_resp_map);
1684 if (status) {
1685 mlog_errno(status);
1686 goto bail;
1687 }
1688 }
1689
1690 dlm_send_join_asserts(dlm, ctxt->yes_resp_map);
1691
1692 /* Joined state *must* be set before the joining node
1693 * information, otherwise the query_join handler may read no
1694 * current joiner but a state of NEW and tell joining nodes
1695 * we're not in the domain. */
1696 spin_lock(&dlm_domain_lock);
1697 dlm->dlm_state = DLM_CTXT_JOINED;
1698 dlm->num_joins++;
1699 spin_unlock(&dlm_domain_lock);
1700
1701 bail:
1702 spin_lock(&dlm->spinlock);
1703 __dlm_set_joining_node(dlm, DLM_LOCK_RES_OWNER_UNKNOWN);
1704 if (!status)
1705 __dlm_print_nodes(dlm);
1706 spin_unlock(&dlm->spinlock);
1707
1708 if (ctxt) {
1709 /* Do we need to send a cancel message to any nodes? */
1710 if (status < 0) {
1711 tmpstat = dlm_send_join_cancels(dlm,
1712 ctxt->yes_resp_map,
1713 sizeof(ctxt->yes_resp_map));
1714 if (tmpstat < 0)
1715 mlog_errno(tmpstat);
1716 }
1717 kfree(ctxt);
1718 }
1719
1720 mlog(0, "returning %d\n", status);
1721 return status;
1722 }
1723
1724 static void dlm_unregister_domain_handlers(struct dlm_ctxt *dlm)
1725 {
1726 o2hb_unregister_callback(dlm->name, &dlm->dlm_hb_up);
1727 o2hb_unregister_callback(dlm->name, &dlm->dlm_hb_down);
1728 o2net_unregister_handler_list(&dlm->dlm_domain_handlers);
1729 }
1730
1731 static int dlm_register_domain_handlers(struct dlm_ctxt *dlm)
1732 {
1733 int status;
1734
1735 mlog(0, "registering handlers.\n");
1736
1737 o2hb_setup_callback(&dlm->dlm_hb_down, O2HB_NODE_DOWN_CB,
1738 dlm_hb_node_down_cb, dlm, DLM_HB_NODE_DOWN_PRI);
1739 status = o2hb_register_callback(dlm->name, &dlm->dlm_hb_down);
1740 if (status)
1741 goto bail;
1742
1743 o2hb_setup_callback(&dlm->dlm_hb_up, O2HB_NODE_UP_CB,
1744 dlm_hb_node_up_cb, dlm, DLM_HB_NODE_UP_PRI);
1745 status = o2hb_register_callback(dlm->name, &dlm->dlm_hb_up);
1746 if (status)
1747 goto bail;
1748
1749 status = o2net_register_handler(DLM_MASTER_REQUEST_MSG, dlm->key,
1750 sizeof(struct dlm_master_request),
1751 dlm_master_request_handler,
1752 dlm, NULL, &dlm->dlm_domain_handlers);
1753 if (status)
1754 goto bail;
1755
1756 status = o2net_register_handler(DLM_ASSERT_MASTER_MSG, dlm->key,
1757 sizeof(struct dlm_assert_master),
1758 dlm_assert_master_handler,
1759 dlm, dlm_assert_master_post_handler,
1760 &dlm->dlm_domain_handlers);
1761 if (status)
1762 goto bail;
1763
1764 status = o2net_register_handler(DLM_CREATE_LOCK_MSG, dlm->key,
1765 sizeof(struct dlm_create_lock),
1766 dlm_create_lock_handler,
1767 dlm, NULL, &dlm->dlm_domain_handlers);
1768 if (status)
1769 goto bail;
1770
1771 status = o2net_register_handler(DLM_CONVERT_LOCK_MSG, dlm->key,
1772 DLM_CONVERT_LOCK_MAX_LEN,
1773 dlm_convert_lock_handler,
1774 dlm, NULL, &dlm->dlm_domain_handlers);
1775 if (status)
1776 goto bail;
1777
1778 status = o2net_register_handler(DLM_UNLOCK_LOCK_MSG, dlm->key,
1779 DLM_UNLOCK_LOCK_MAX_LEN,
1780 dlm_unlock_lock_handler,
1781 dlm, NULL, &dlm->dlm_domain_handlers);
1782 if (status)
1783 goto bail;
1784
1785 status = o2net_register_handler(DLM_PROXY_AST_MSG, dlm->key,
1786 DLM_PROXY_AST_MAX_LEN,
1787 dlm_proxy_ast_handler,
1788 dlm, NULL, &dlm->dlm_domain_handlers);
1789 if (status)
1790 goto bail;
1791
1792 status = o2net_register_handler(DLM_EXIT_DOMAIN_MSG, dlm->key,
1793 sizeof(struct dlm_exit_domain),
1794 dlm_exit_domain_handler,
1795 dlm, NULL, &dlm->dlm_domain_handlers);
1796 if (status)
1797 goto bail;
1798
1799 status = o2net_register_handler(DLM_DEREF_LOCKRES_MSG, dlm->key,
1800 sizeof(struct dlm_deref_lockres),
1801 dlm_deref_lockres_handler,
1802 dlm, NULL, &dlm->dlm_domain_handlers);
1803 if (status)
1804 goto bail;
1805
1806 status = o2net_register_handler(DLM_MIGRATE_REQUEST_MSG, dlm->key,
1807 sizeof(struct dlm_migrate_request),
1808 dlm_migrate_request_handler,
1809 dlm, NULL, &dlm->dlm_domain_handlers);
1810 if (status)
1811 goto bail;
1812
1813 status = o2net_register_handler(DLM_MIG_LOCKRES_MSG, dlm->key,
1814 DLM_MIG_LOCKRES_MAX_LEN,
1815 dlm_mig_lockres_handler,
1816 dlm, NULL, &dlm->dlm_domain_handlers);
1817 if (status)
1818 goto bail;
1819
1820 status = o2net_register_handler(DLM_MASTER_REQUERY_MSG, dlm->key,
1821 sizeof(struct dlm_master_requery),
1822 dlm_master_requery_handler,
1823 dlm, NULL, &dlm->dlm_domain_handlers);
1824 if (status)
1825 goto bail;
1826
1827 status = o2net_register_handler(DLM_LOCK_REQUEST_MSG, dlm->key,
1828 sizeof(struct dlm_lock_request),
1829 dlm_request_all_locks_handler,
1830 dlm, NULL, &dlm->dlm_domain_handlers);
1831 if (status)
1832 goto bail;
1833
1834 status = o2net_register_handler(DLM_RECO_DATA_DONE_MSG, dlm->key,
1835 sizeof(struct dlm_reco_data_done),
1836 dlm_reco_data_done_handler,
1837 dlm, NULL, &dlm->dlm_domain_handlers);
1838 if (status)
1839 goto bail;
1840
1841 status = o2net_register_handler(DLM_BEGIN_RECO_MSG, dlm->key,
1842 sizeof(struct dlm_begin_reco),
1843 dlm_begin_reco_handler,
1844 dlm, NULL, &dlm->dlm_domain_handlers);
1845 if (status)
1846 goto bail;
1847
1848 status = o2net_register_handler(DLM_FINALIZE_RECO_MSG, dlm->key,
1849 sizeof(struct dlm_finalize_reco),
1850 dlm_finalize_reco_handler,
1851 dlm, NULL, &dlm->dlm_domain_handlers);
1852 if (status)
1853 goto bail;
1854
1855 status = o2net_register_handler(DLM_BEGIN_EXIT_DOMAIN_MSG, dlm->key,
1856 sizeof(struct dlm_exit_domain),
1857 dlm_begin_exit_domain_handler,
1858 dlm, NULL, &dlm->dlm_domain_handlers);
1859 if (status)
1860 goto bail;
1861
1862 bail:
1863 if (status)
1864 dlm_unregister_domain_handlers(dlm);
1865
1866 return status;
1867 }
1868
1869 static int dlm_join_domain(struct dlm_ctxt *dlm)
1870 {
1871 int status;
1872 unsigned int backoff;
1873 unsigned int total_backoff = 0;
1874
1875 BUG_ON(!dlm);
1876
1877 mlog(0, "Join domain %s\n", dlm->name);
1878
1879 status = dlm_register_domain_handlers(dlm);
1880 if (status) {
1881 mlog_errno(status);
1882 goto bail;
1883 }
1884
1885 status = dlm_debug_init(dlm);
1886 if (status < 0) {
1887 mlog_errno(status);
1888 goto bail;
1889 }
1890
1891 status = dlm_launch_thread(dlm);
1892 if (status < 0) {
1893 mlog_errno(status);
1894 goto bail;
1895 }
1896
1897 status = dlm_launch_recovery_thread(dlm);
1898 if (status < 0) {
1899 mlog_errno(status);
1900 goto bail;
1901 }
1902
1903 dlm->dlm_worker = create_singlethread_workqueue("dlm_wq");
1904 if (!dlm->dlm_worker) {
1905 status = -ENOMEM;
1906 mlog_errno(status);
1907 goto bail;
1908 }
1909
1910 do {
1911 status = dlm_try_to_join_domain(dlm);
1912
1913 /* If we're racing another node to the join, then we
1914 * need to back off temporarily and let them
1915 * complete. */
1916 #define DLM_JOIN_TIMEOUT_MSECS 90000
1917 if (status == -EAGAIN) {
1918 if (signal_pending(current)) {
1919 status = -ERESTARTSYS;
1920 goto bail;
1921 }
1922
1923 if (total_backoff >
1924 msecs_to_jiffies(DLM_JOIN_TIMEOUT_MSECS)) {
1925 status = -ERESTARTSYS;
1926 mlog(ML_NOTICE, "Timed out joining dlm domain "
1927 "%s after %u msecs\n", dlm->name,
1928 jiffies_to_msecs(total_backoff));
1929 goto bail;
1930 }
1931
1932 /*
1933 * <chip> After you!
1934 * <dale> No, after you!
1935 * <chip> I insist!
1936 * <dale> But you first!
1937 * ...
1938 */
1939 backoff = (unsigned int)(jiffies & 0x3);
1940 backoff *= DLM_DOMAIN_BACKOFF_MS;
1941 total_backoff += backoff;
1942 mlog(0, "backoff %d\n", backoff);
1943 msleep(backoff);
1944 }
1945 } while (status == -EAGAIN);
1946
1947 if (status < 0) {
1948 mlog_errno(status);
1949 goto bail;
1950 }
1951
1952 status = 0;
1953 bail:
1954 wake_up(&dlm_domain_events);
1955
1956 if (status) {
1957 dlm_unregister_domain_handlers(dlm);
1958 dlm_debug_shutdown(dlm);
1959 dlm_complete_thread(dlm);
1960 dlm_complete_recovery_thread(dlm);
1961 dlm_destroy_dlm_worker(dlm);
1962 }
1963
1964 return status;
1965 }
1966
1967 static struct dlm_ctxt *dlm_alloc_ctxt(const char *domain,
1968 u32 key)
1969 {
1970 int i;
1971 int ret;
1972 struct dlm_ctxt *dlm = NULL;
1973
1974 dlm = kzalloc(sizeof(*dlm), GFP_KERNEL);
1975 if (!dlm) {
1976 mlog_errno(-ENOMEM);
1977 goto leave;
1978 }
1979
1980 dlm->name = kstrdup(domain, GFP_KERNEL);
1981 if (dlm->name == NULL) {
1982 mlog_errno(-ENOMEM);
1983 kfree(dlm);
1984 dlm = NULL;
1985 goto leave;
1986 }
1987
1988 dlm->lockres_hash = (struct hlist_head **)dlm_alloc_pagevec(DLM_HASH_PAGES);
1989 if (!dlm->lockres_hash) {
1990 mlog_errno(-ENOMEM);
1991 kfree(dlm->name);
1992 kfree(dlm);
1993 dlm = NULL;
1994 goto leave;
1995 }
1996
1997 for (i = 0; i < DLM_HASH_BUCKETS; i++)
1998 INIT_HLIST_HEAD(dlm_lockres_hash(dlm, i));
1999
2000 dlm->master_hash = (struct hlist_head **)
2001 dlm_alloc_pagevec(DLM_HASH_PAGES);
2002 if (!dlm->master_hash) {
2003 mlog_errno(-ENOMEM);
2004 dlm_free_pagevec((void **)dlm->lockres_hash, DLM_HASH_PAGES);
2005 kfree(dlm->name);
2006 kfree(dlm);
2007 dlm = NULL;
2008 goto leave;
2009 }
2010
2011 for (i = 0; i < DLM_HASH_BUCKETS; i++)
2012 INIT_HLIST_HEAD(dlm_master_hash(dlm, i));
2013
2014 dlm->key = key;
2015 dlm->node_num = o2nm_this_node();
2016
2017 ret = dlm_create_debugfs_subroot(dlm);
2018 if (ret < 0) {
2019 dlm_free_pagevec((void **)dlm->master_hash, DLM_HASH_PAGES);
2020 dlm_free_pagevec((void **)dlm->lockres_hash, DLM_HASH_PAGES);
2021 kfree(dlm->name);
2022 kfree(dlm);
2023 dlm = NULL;
2024 goto leave;
2025 }
2026
2027 spin_lock_init(&dlm->spinlock);
2028 spin_lock_init(&dlm->master_lock);
2029 spin_lock_init(&dlm->ast_lock);
2030 spin_lock_init(&dlm->track_lock);
2031 INIT_LIST_HEAD(&dlm->list);
2032 INIT_LIST_HEAD(&dlm->dirty_list);
2033 INIT_LIST_HEAD(&dlm->reco.resources);
2034 INIT_LIST_HEAD(&dlm->reco.received);
2035 INIT_LIST_HEAD(&dlm->reco.node_data);
2036 INIT_LIST_HEAD(&dlm->purge_list);
2037 INIT_LIST_HEAD(&dlm->dlm_domain_handlers);
2038 INIT_LIST_HEAD(&dlm->tracking_list);
2039 dlm->reco.state = 0;
2040
2041 INIT_LIST_HEAD(&dlm->pending_asts);
2042 INIT_LIST_HEAD(&dlm->pending_basts);
2043
2044 mlog(0, "dlm->recovery_map=%p, &(dlm->recovery_map[0])=%p\n",
2045 dlm->recovery_map, &(dlm->recovery_map[0]));
2046
2047 memset(dlm->recovery_map, 0, sizeof(dlm->recovery_map));
2048 memset(dlm->live_nodes_map, 0, sizeof(dlm->live_nodes_map));
2049 memset(dlm->domain_map, 0, sizeof(dlm->domain_map));
2050
2051 dlm->dlm_thread_task = NULL;
2052 dlm->dlm_reco_thread_task = NULL;
2053 dlm->dlm_worker = NULL;
2054 init_waitqueue_head(&dlm->dlm_thread_wq);
2055 init_waitqueue_head(&dlm->dlm_reco_thread_wq);
2056 init_waitqueue_head(&dlm->reco.event);
2057 init_waitqueue_head(&dlm->ast_wq);
2058 init_waitqueue_head(&dlm->migration_wq);
2059 INIT_LIST_HEAD(&dlm->mle_hb_events);
2060
2061 dlm->joining_node = DLM_LOCK_RES_OWNER_UNKNOWN;
2062 init_waitqueue_head(&dlm->dlm_join_events);
2063
2064 dlm->reco.new_master = O2NM_INVALID_NODE_NUM;
2065 dlm->reco.dead_node = O2NM_INVALID_NODE_NUM;
2066
2067 atomic_set(&dlm->res_tot_count, 0);
2068 atomic_set(&dlm->res_cur_count, 0);
2069 for (i = 0; i < DLM_MLE_NUM_TYPES; ++i) {
2070 atomic_set(&dlm->mle_tot_count[i], 0);
2071 atomic_set(&dlm->mle_cur_count[i], 0);
2072 }
2073
2074 spin_lock_init(&dlm->work_lock);
2075 INIT_LIST_HEAD(&dlm->work_list);
2076 INIT_WORK(&dlm->dispatched_work, dlm_dispatch_work);
2077
2078 kref_init(&dlm->dlm_refs);
2079 dlm->dlm_state = DLM_CTXT_NEW;
2080
2081 INIT_LIST_HEAD(&dlm->dlm_eviction_callbacks);
2082
2083 mlog(0, "context init: refcount %u\n",
2084 atomic_read(&dlm->dlm_refs.refcount));
2085
2086 leave:
2087 return dlm;
2088 }
2089
2090 /*
2091 * Compare a requested locking protocol version against the current one.
2092 *
2093 * If the major numbers are different, they are incompatible.
2094 * If the current minor is greater than the request, they are incompatible.
2095 * If the current minor is less than or equal to the request, they are
2096 * compatible, and the requester should run at the current minor version.
2097 */
2098 static int dlm_protocol_compare(struct dlm_protocol_version *existing,
2099 struct dlm_protocol_version *request)
2100 {
2101 if (existing->pv_major != request->pv_major)
2102 return 1;
2103
2104 if (existing->pv_minor > request->pv_minor)
2105 return 1;
2106
2107 if (existing->pv_minor < request->pv_minor)
2108 request->pv_minor = existing->pv_minor;
2109
2110 return 0;
2111 }
2112
2113 /*
2114 * dlm_register_domain: one-time setup per "domain".
2115 *
2116 * The filesystem passes in the requested locking version via proto.
2117 * If registration was successful, proto will contain the negotiated
2118 * locking protocol.
2119 */
2120 struct dlm_ctxt * dlm_register_domain(const char *domain,
2121 u32 key,
2122 struct dlm_protocol_version *fs_proto)
2123 {
2124 int ret;
2125 struct dlm_ctxt *dlm = NULL;
2126 struct dlm_ctxt *new_ctxt = NULL;
2127
2128 if (strlen(domain) >= O2NM_MAX_NAME_LEN) {
2129 ret = -ENAMETOOLONG;
2130 mlog(ML_ERROR, "domain name length too long\n");
2131 goto leave;
2132 }
2133
2134 if (!o2hb_check_local_node_heartbeating()) {
2135 mlog(ML_ERROR, "the local node has not been configured, or is "
2136 "not heartbeating\n");
2137 ret = -EPROTO;
2138 goto leave;
2139 }
2140
2141 mlog(0, "register called for domain \"%s\"\n", domain);
2142
2143 retry:
2144 dlm = NULL;
2145 if (signal_pending(current)) {
2146 ret = -ERESTARTSYS;
2147 mlog_errno(ret);
2148 goto leave;
2149 }
2150
2151 spin_lock(&dlm_domain_lock);
2152
2153 dlm = __dlm_lookup_domain(domain);
2154 if (dlm) {
2155 if (dlm->dlm_state != DLM_CTXT_JOINED) {
2156 spin_unlock(&dlm_domain_lock);
2157
2158 mlog(0, "This ctxt is not joined yet!\n");
2159 wait_event_interruptible(dlm_domain_events,
2160 dlm_wait_on_domain_helper(
2161 domain));
2162 goto retry;
2163 }
2164
2165 if (dlm_protocol_compare(&dlm->fs_locking_proto, fs_proto)) {
2166 spin_unlock(&dlm_domain_lock);
2167 mlog(ML_ERROR,
2168 "Requested locking protocol version is not "
2169 "compatible with already registered domain "
2170 "\"%s\"\n", domain);
2171 ret = -EPROTO;
2172 goto leave;
2173 }
2174
2175 __dlm_get(dlm);
2176 dlm->num_joins++;
2177
2178 spin_unlock(&dlm_domain_lock);
2179
2180 ret = 0;
2181 goto leave;
2182 }
2183
2184 /* doesn't exist */
2185 if (!new_ctxt) {
2186 spin_unlock(&dlm_domain_lock);
2187
2188 new_ctxt = dlm_alloc_ctxt(domain, key);
2189 if (new_ctxt)
2190 goto retry;
2191
2192 ret = -ENOMEM;
2193 mlog_errno(ret);
2194 goto leave;
2195 }
2196
2197 /* a little variable switch-a-roo here... */
2198 dlm = new_ctxt;
2199 new_ctxt = NULL;
2200
2201 /* add the new domain */
2202 list_add_tail(&dlm->list, &dlm_domains);
2203 spin_unlock(&dlm_domain_lock);
2204
2205 /*
2206 * Pass the locking protocol version into the join. If the join
2207 * succeeds, it will have the negotiated protocol set.
2208 */
2209 dlm->dlm_locking_proto = dlm_protocol;
2210 dlm->fs_locking_proto = *fs_proto;
2211
2212 ret = dlm_join_domain(dlm);
2213 if (ret) {
2214 mlog_errno(ret);
2215 dlm_put(dlm);
2216 goto leave;
2217 }
2218
2219 /* Tell the caller what locking protocol we negotiated */
2220 *fs_proto = dlm->fs_locking_proto;
2221
2222 ret = 0;
2223 leave:
2224 if (new_ctxt)
2225 dlm_free_ctxt_mem(new_ctxt);
2226
2227 if (ret < 0)
2228 dlm = ERR_PTR(ret);
2229
2230 return dlm;
2231 }
2232 EXPORT_SYMBOL_GPL(dlm_register_domain);
2233
2234 static LIST_HEAD(dlm_join_handlers);
2235
2236 static void dlm_unregister_net_handlers(void)
2237 {
2238 o2net_unregister_handler_list(&dlm_join_handlers);
2239 }
2240
2241 static int dlm_register_net_handlers(void)
2242 {
2243 int status = 0;
2244
2245 status = o2net_register_handler(DLM_QUERY_JOIN_MSG, DLM_MOD_KEY,
2246 sizeof(struct dlm_query_join_request),
2247 dlm_query_join_handler,
2248 NULL, NULL, &dlm_join_handlers);
2249 if (status)
2250 goto bail;
2251
2252 status = o2net_register_handler(DLM_ASSERT_JOINED_MSG, DLM_MOD_KEY,
2253 sizeof(struct dlm_assert_joined),
2254 dlm_assert_joined_handler,
2255 NULL, NULL, &dlm_join_handlers);
2256 if (status)
2257 goto bail;
2258
2259 status = o2net_register_handler(DLM_CANCEL_JOIN_MSG, DLM_MOD_KEY,
2260 sizeof(struct dlm_cancel_join),
2261 dlm_cancel_join_handler,
2262 NULL, NULL, &dlm_join_handlers);
2263 if (status)
2264 goto bail;
2265
2266 status = o2net_register_handler(DLM_QUERY_REGION, DLM_MOD_KEY,
2267 sizeof(struct dlm_query_region),
2268 dlm_query_region_handler,
2269 NULL, NULL, &dlm_join_handlers);
2270
2271 if (status)
2272 goto bail;
2273
2274 status = o2net_register_handler(DLM_QUERY_NODEINFO, DLM_MOD_KEY,
2275 sizeof(struct dlm_query_nodeinfo),
2276 dlm_query_nodeinfo_handler,
2277 NULL, NULL, &dlm_join_handlers);
2278 bail:
2279 if (status < 0)
2280 dlm_unregister_net_handlers();
2281
2282 return status;
2283 }
2284
2285 /* Domain eviction callback handling.
2286 *
2287 * The file system requires notification of node death *before* the
2288 * dlm completes it's recovery work, otherwise it may be able to
2289 * acquire locks on resources requiring recovery. Since the dlm can
2290 * evict a node from it's domain *before* heartbeat fires, a similar
2291 * mechanism is required. */
2292
2293 /* Eviction is not expected to happen often, so a per-domain lock is
2294 * not necessary. Eviction callbacks are allowed to sleep for short
2295 * periods of time. */
2296 static DECLARE_RWSEM(dlm_callback_sem);
2297
2298 void dlm_fire_domain_eviction_callbacks(struct dlm_ctxt *dlm,
2299 int node_num)
2300 {
2301 struct list_head *iter;
2302 struct dlm_eviction_cb *cb;
2303
2304 down_read(&dlm_callback_sem);
2305 list_for_each(iter, &dlm->dlm_eviction_callbacks) {
2306 cb = list_entry(iter, struct dlm_eviction_cb, ec_item);
2307
2308 cb->ec_func(node_num, cb->ec_data);
2309 }
2310 up_read(&dlm_callback_sem);
2311 }
2312
2313 void dlm_setup_eviction_cb(struct dlm_eviction_cb *cb,
2314 dlm_eviction_func *f,
2315 void *data)
2316 {
2317 INIT_LIST_HEAD(&cb->ec_item);
2318 cb->ec_func = f;
2319 cb->ec_data = data;
2320 }
2321 EXPORT_SYMBOL_GPL(dlm_setup_eviction_cb);
2322
2323 void dlm_register_eviction_cb(struct dlm_ctxt *dlm,
2324 struct dlm_eviction_cb *cb)
2325 {
2326 down_write(&dlm_callback_sem);
2327 list_add_tail(&cb->ec_item, &dlm->dlm_eviction_callbacks);
2328 up_write(&dlm_callback_sem);
2329 }
2330 EXPORT_SYMBOL_GPL(dlm_register_eviction_cb);
2331
2332 void dlm_unregister_eviction_cb(struct dlm_eviction_cb *cb)
2333 {
2334 down_write(&dlm_callback_sem);
2335 list_del_init(&cb->ec_item);
2336 up_write(&dlm_callback_sem);
2337 }
2338 EXPORT_SYMBOL_GPL(dlm_unregister_eviction_cb);
2339
2340 static int __init dlm_init(void)
2341 {
2342 int status;
2343
2344 dlm_print_version();
2345
2346 status = dlm_init_mle_cache();
2347 if (status) {
2348 mlog(ML_ERROR, "Could not create o2dlm_mle slabcache\n");
2349 goto error;
2350 }
2351
2352 status = dlm_init_master_caches();
2353 if (status) {
2354 mlog(ML_ERROR, "Could not create o2dlm_lockres and "
2355 "o2dlm_lockname slabcaches\n");
2356 goto error;
2357 }
2358
2359 status = dlm_init_lock_cache();
2360 if (status) {
2361 mlog(ML_ERROR, "Count not create o2dlm_lock slabcache\n");
2362 goto error;
2363 }
2364
2365 status = dlm_register_net_handlers();
2366 if (status) {
2367 mlog(ML_ERROR, "Unable to register network handlers\n");
2368 goto error;
2369 }
2370
2371 status = dlm_create_debugfs_root();
2372 if (status)
2373 goto error;
2374
2375 return 0;
2376 error:
2377 dlm_unregister_net_handlers();
2378 dlm_destroy_lock_cache();
2379 dlm_destroy_master_caches();
2380 dlm_destroy_mle_cache();
2381 return -1;
2382 }
2383
2384 static void __exit dlm_exit (void)
2385 {
2386 dlm_destroy_debugfs_root();
2387 dlm_unregister_net_handlers();
2388 dlm_destroy_lock_cache();
2389 dlm_destroy_master_caches();
2390 dlm_destroy_mle_cache();
2391 }
2392
2393 MODULE_AUTHOR("Oracle");
2394 MODULE_LICENSE("GPL");
2395
2396 module_init(dlm_init);
2397 module_exit(dlm_exit);
linux-next