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Linux 3.10.35
[linux/fpc-iii.git] / fs / ocfs2 / dlm / dlmdomain.c
blobdbb17c07656ae3ca88c75f02bb4d75100190ffea
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_ctxt *dlm, struct dlm_lock_resource *res)
161 {
162 if (hlist_unhashed(&res->hash_node))
163 return;
164
165 mlog(0, "%s: Unhash res %.*s\n", dlm->name, res->lockname.len,
166 res->lockname.name);
167 hlist_del_init(&res->hash_node);
168 dlm_lockres_put(res);
169 }
170
171 void __dlm_insert_lockres(struct dlm_ctxt *dlm, struct dlm_lock_resource *res)
172 {
173 struct hlist_head *bucket;
174 struct qstr *q;
175
176 assert_spin_locked(&dlm->spinlock);
177
178 q = &res->lockname;
179 bucket = dlm_lockres_hash(dlm, q->hash);
180
181 /* get a reference for our hashtable */
182 dlm_lockres_get(res);
183
184 hlist_add_head(&res->hash_node, bucket);
185
186 mlog(0, "%s: Hash res %.*s\n", dlm->name, res->lockname.len,
187 res->lockname.name);
188 }
189
190 struct dlm_lock_resource * __dlm_lookup_lockres_full(struct dlm_ctxt *dlm,
191 const char *name,
192 unsigned int len,
193 unsigned int hash)
194 {
195 struct hlist_head *bucket;
196 struct hlist_node *list;
197
198 mlog(0, "%.*s\n", len, name);
199
200 assert_spin_locked(&dlm->spinlock);
201
202 bucket = dlm_lockres_hash(dlm, hash);
203
204 hlist_for_each(list, bucket) {
205 struct dlm_lock_resource *res = hlist_entry(list,
206 struct dlm_lock_resource, hash_node);
207 if (res->lockname.name[0] != name[0])
208 continue;
209 if (unlikely(res->lockname.len != len))
210 continue;
211 if (memcmp(res->lockname.name + 1, name + 1, len - 1))
212 continue;
213 dlm_lockres_get(res);
214 return res;
215 }
216 return NULL;
217 }
218
219 /* intended to be called by functions which do not care about lock
220 * resources which are being purged (most net _handler functions).
221 * this will return NULL for any lock resource which is found but
222 * currently in the process of dropping its mastery reference.
223 * use __dlm_lookup_lockres_full when you need the lock resource
224 * regardless (e.g. dlm_get_lock_resource) */
225 struct dlm_lock_resource * __dlm_lookup_lockres(struct dlm_ctxt *dlm,
226 const char *name,
227 unsigned int len,
228 unsigned int hash)
229 {
230 struct dlm_lock_resource *res = NULL;
231
232 mlog(0, "%.*s\n", len, name);
233
234 assert_spin_locked(&dlm->spinlock);
235
236 res = __dlm_lookup_lockres_full(dlm, name, len, hash);
237 if (res) {
238 spin_lock(&res->spinlock);
239 if (res->state & DLM_LOCK_RES_DROPPING_REF) {
240 spin_unlock(&res->spinlock);
241 dlm_lockres_put(res);
242 return NULL;
243 }
244 spin_unlock(&res->spinlock);
245 }
246
247 return res;
248 }
249
250 struct dlm_lock_resource * dlm_lookup_lockres(struct dlm_ctxt *dlm,
251 const char *name,
252 unsigned int len)
253 {
254 struct dlm_lock_resource *res;
255 unsigned int hash = dlm_lockid_hash(name, len);
256
257 spin_lock(&dlm->spinlock);
258 res = __dlm_lookup_lockres(dlm, name, len, hash);
259 spin_unlock(&dlm->spinlock);
260 return res;
261 }
262
263 static struct dlm_ctxt * __dlm_lookup_domain_full(const char *domain, int len)
264 {
265 struct dlm_ctxt *tmp = NULL;
266 struct list_head *iter;
267
268 assert_spin_locked(&dlm_domain_lock);
269
270 /* tmp->name here is always NULL terminated,
271 * but domain may not be! */
272 list_for_each(iter, &dlm_domains) {
273 tmp = list_entry (iter, struct dlm_ctxt, list);
274 if (strlen(tmp->name) == len &&
275 memcmp(tmp->name, domain, len)==0)
276 break;
277 tmp = NULL;
278 }
279
280 return tmp;
281 }
282
283 /* For null terminated domain strings ONLY */
284 static struct dlm_ctxt * __dlm_lookup_domain(const char *domain)
285 {
286 assert_spin_locked(&dlm_domain_lock);
287
288 return __dlm_lookup_domain_full(domain, strlen(domain));
289 }
290
291
292 /* returns true on one of two conditions:
293 * 1) the domain does not exist
294 * 2) the domain exists and it's state is "joined" */
295 static int dlm_wait_on_domain_helper(const char *domain)
296 {
297 int ret = 0;
298 struct dlm_ctxt *tmp = NULL;
299
300 spin_lock(&dlm_domain_lock);
301
302 tmp = __dlm_lookup_domain(domain);
303 if (!tmp)
304 ret = 1;
305 else if (tmp->dlm_state == DLM_CTXT_JOINED)
306 ret = 1;
307
308 spin_unlock(&dlm_domain_lock);
309 return ret;
310 }
311
312 static void dlm_free_ctxt_mem(struct dlm_ctxt *dlm)
313 {
314 dlm_destroy_debugfs_subroot(dlm);
315
316 if (dlm->lockres_hash)
317 dlm_free_pagevec((void **)dlm->lockres_hash, DLM_HASH_PAGES);
318
319 if (dlm->master_hash)
320 dlm_free_pagevec((void **)dlm->master_hash, DLM_HASH_PAGES);
321
322 kfree(dlm->name);
323 kfree(dlm);
324 }
325
326 /* A little strange - this function will be called while holding
327 * dlm_domain_lock and is expected to be holding it on the way out. We
328 * will however drop and reacquire it multiple times */
329 static void dlm_ctxt_release(struct kref *kref)
330 {
331 struct dlm_ctxt *dlm;
332
333 dlm = container_of(kref, struct dlm_ctxt, dlm_refs);
334
335 BUG_ON(dlm->num_joins);
336 BUG_ON(dlm->dlm_state == DLM_CTXT_JOINED);
337
338 /* we may still be in the list if we hit an error during join. */
339 list_del_init(&dlm->list);
340
341 spin_unlock(&dlm_domain_lock);
342
343 mlog(0, "freeing memory from domain %s\n", dlm->name);
344
345 wake_up(&dlm_domain_events);
346
347 dlm_free_ctxt_mem(dlm);
348
349 spin_lock(&dlm_domain_lock);
350 }
351
352 void dlm_put(struct dlm_ctxt *dlm)
353 {
354 spin_lock(&dlm_domain_lock);
355 kref_put(&dlm->dlm_refs, dlm_ctxt_release);
356 spin_unlock(&dlm_domain_lock);
357 }
358
359 static void __dlm_get(struct dlm_ctxt *dlm)
360 {
361 kref_get(&dlm->dlm_refs);
362 }
363
364 /* given a questionable reference to a dlm object, gets a reference if
365 * it can find it in the list, otherwise returns NULL in which case
366 * you shouldn't trust your pointer. */
367 struct dlm_ctxt *dlm_grab(struct dlm_ctxt *dlm)
368 {
369 struct list_head *iter;
370 struct dlm_ctxt *target = NULL;
371
372 spin_lock(&dlm_domain_lock);
373
374 list_for_each(iter, &dlm_domains) {
375 target = list_entry (iter, struct dlm_ctxt, list);
376
377 if (target == dlm) {
378 __dlm_get(target);
379 break;
380 }
381
382 target = NULL;
383 }
384
385 spin_unlock(&dlm_domain_lock);
386
387 return target;
388 }
389
390 int dlm_domain_fully_joined(struct dlm_ctxt *dlm)
391 {
392 int ret;
393
394 spin_lock(&dlm_domain_lock);
395 ret = (dlm->dlm_state == DLM_CTXT_JOINED) ||
396 (dlm->dlm_state == DLM_CTXT_IN_SHUTDOWN);
397 spin_unlock(&dlm_domain_lock);
398
399 return ret;
400 }
401
402 static void dlm_destroy_dlm_worker(struct dlm_ctxt *dlm)
403 {
404 if (dlm->dlm_worker) {
405 flush_workqueue(dlm->dlm_worker);
406 destroy_workqueue(dlm->dlm_worker);
407 dlm->dlm_worker = NULL;
408 }
409 }
410
411 static void dlm_complete_dlm_shutdown(struct dlm_ctxt *dlm)
412 {
413 dlm_unregister_domain_handlers(dlm);
414 dlm_debug_shutdown(dlm);
415 dlm_complete_thread(dlm);
416 dlm_complete_recovery_thread(dlm);
417 dlm_destroy_dlm_worker(dlm);
418
419 /* We've left the domain. Now we can take ourselves out of the
420 * list and allow the kref stuff to help us free the
421 * memory. */
422 spin_lock(&dlm_domain_lock);
423 list_del_init(&dlm->list);
424 spin_unlock(&dlm_domain_lock);
425
426 /* Wake up anyone waiting for us to remove this domain */
427 wake_up(&dlm_domain_events);
428 }
429
430 static int dlm_migrate_all_locks(struct dlm_ctxt *dlm)
431 {
432 int i, num, n, ret = 0;
433 struct dlm_lock_resource *res;
434 struct hlist_node *iter;
435 struct hlist_head *bucket;
436 int dropped;
437
438 mlog(0, "Migrating locks from domain %s\n", dlm->name);
439
440 num = 0;
441 spin_lock(&dlm->spinlock);
442 for (i = 0; i < DLM_HASH_BUCKETS; i++) {
443 redo_bucket:
444 n = 0;
445 bucket = dlm_lockres_hash(dlm, i);
446 iter = bucket->first;
447 while (iter) {
448 n++;
449 res = hlist_entry(iter, struct dlm_lock_resource,
450 hash_node);
451 dlm_lockres_get(res);
452 /* migrate, if necessary. this will drop the dlm
453 * spinlock and retake it if it does migration. */
454 dropped = dlm_empty_lockres(dlm, res);
455
456 spin_lock(&res->spinlock);
457 if (dropped)
458 __dlm_lockres_calc_usage(dlm, res);
459 else
460 iter = res->hash_node.next;
461 spin_unlock(&res->spinlock);
462
463 dlm_lockres_put(res);
464
465 if (dropped) {
466 cond_resched_lock(&dlm->spinlock);
467 goto redo_bucket;
468 }
469 }
470 cond_resched_lock(&dlm->spinlock);
471 num += n;
472 }
473 spin_unlock(&dlm->spinlock);
474 wake_up(&dlm->dlm_thread_wq);
475
476 /* let the dlm thread take care of purging, keep scanning until
477 * nothing remains in the hash */
478 if (num) {
479 mlog(0, "%s: %d lock resources in hash last pass\n",
480 dlm->name, num);
481 ret = -EAGAIN;
482 }
483 mlog(0, "DONE Migrating locks from domain %s\n", dlm->name);
484 return ret;
485 }
486
487 static int dlm_no_joining_node(struct dlm_ctxt *dlm)
488 {
489 int ret;
490
491 spin_lock(&dlm->spinlock);
492 ret = dlm->joining_node == DLM_LOCK_RES_OWNER_UNKNOWN;
493 spin_unlock(&dlm->spinlock);
494
495 return ret;
496 }
497
498 static int dlm_begin_exit_domain_handler(struct o2net_msg *msg, u32 len,
499 void *data, void **ret_data)
500 {
501 struct dlm_ctxt *dlm = data;
502 unsigned int node;
503 struct dlm_exit_domain *exit_msg = (struct dlm_exit_domain *) msg->buf;
504
505 if (!dlm_grab(dlm))
506 return 0;
507
508 node = exit_msg->node_idx;
509 mlog(0, "%s: Node %u sent a begin exit domain message\n", dlm->name, node);
510
511 spin_lock(&dlm->spinlock);
512 set_bit(node, dlm->exit_domain_map);
513 spin_unlock(&dlm->spinlock);
514
515 dlm_put(dlm);
516
517 return 0;
518 }
519
520 static void dlm_mark_domain_leaving(struct dlm_ctxt *dlm)
521 {
522 /* Yikes, a double spinlock! I need domain_lock for the dlm
523 * state and the dlm spinlock for join state... Sorry! */
524 again:
525 spin_lock(&dlm_domain_lock);
526 spin_lock(&dlm->spinlock);
527
528 if (dlm->joining_node != DLM_LOCK_RES_OWNER_UNKNOWN) {
529 mlog(0, "Node %d is joining, we wait on it.\n",
530 dlm->joining_node);
531 spin_unlock(&dlm->spinlock);
532 spin_unlock(&dlm_domain_lock);
533
534 wait_event(dlm->dlm_join_events, dlm_no_joining_node(dlm));
535 goto again;
536 }
537
538 dlm->dlm_state = DLM_CTXT_LEAVING;
539 spin_unlock(&dlm->spinlock);
540 spin_unlock(&dlm_domain_lock);
541 }
542
543 static void __dlm_print_nodes(struct dlm_ctxt *dlm)
544 {
545 int node = -1, num = 0;
546
547 assert_spin_locked(&dlm->spinlock);
548
549 printk("( ");
550 while ((node = find_next_bit(dlm->domain_map, O2NM_MAX_NODES,
551 node + 1)) < O2NM_MAX_NODES) {
552 printk("%d ", node);
553 ++num;
554 }
555 printk(") %u nodes\n", num);
556 }
557
558 static int dlm_exit_domain_handler(struct o2net_msg *msg, u32 len, void *data,
559 void **ret_data)
560 {
561 struct dlm_ctxt *dlm = data;
562 unsigned int node;
563 struct dlm_exit_domain *exit_msg = (struct dlm_exit_domain *) msg->buf;
564
565 mlog(0, "%p %u %p", msg, len, data);
566
567 if (!dlm_grab(dlm))
568 return 0;
569
570 node = exit_msg->node_idx;
571
572 spin_lock(&dlm->spinlock);
573 clear_bit(node, dlm->domain_map);
574 clear_bit(node, dlm->exit_domain_map);
575 printk(KERN_NOTICE "o2dlm: Node %u leaves domain %s ", node, dlm->name);
576 __dlm_print_nodes(dlm);
577
578 /* notify anything attached to the heartbeat events */
579 dlm_hb_event_notify_attached(dlm, node, 0);
580
581 spin_unlock(&dlm->spinlock);
582
583 dlm_put(dlm);
584
585 return 0;
586 }
587
588 static int dlm_send_one_domain_exit(struct dlm_ctxt *dlm, u32 msg_type,
589 unsigned int node)
590 {
591 int status;
592 struct dlm_exit_domain leave_msg;
593
594 mlog(0, "%s: Sending domain exit message %u to node %u\n", dlm->name,
595 msg_type, node);
596
597 memset(&leave_msg, 0, sizeof(leave_msg));
598 leave_msg.node_idx = dlm->node_num;
599
600 status = o2net_send_message(msg_type, dlm->key, &leave_msg,
601 sizeof(leave_msg), node, NULL);
602 if (status < 0)
603 mlog(ML_ERROR, "Error %d sending domain exit message %u "
604 "to node %u on domain %s\n", status, msg_type, node,
605 dlm->name);
606
607 return status;
608 }
609
610 static void dlm_begin_exit_domain(struct dlm_ctxt *dlm)
611 {
612 int node = -1;
613
614 /* Support for begin exit domain was added in 1.2 */
615 if (dlm->dlm_locking_proto.pv_major == 1 &&
616 dlm->dlm_locking_proto.pv_minor < 2)
617 return;
618
619 /*
620 * Unlike DLM_EXIT_DOMAIN_MSG, DLM_BEGIN_EXIT_DOMAIN_MSG is purely
621 * informational. Meaning if a node does not receive the message,
622 * so be it.
623 */
624 spin_lock(&dlm->spinlock);
625 while (1) {
626 node = find_next_bit(dlm->domain_map, O2NM_MAX_NODES, node + 1);
627 if (node >= O2NM_MAX_NODES)
628 break;
629 if (node == dlm->node_num)
630 continue;
631
632 spin_unlock(&dlm->spinlock);
633 dlm_send_one_domain_exit(dlm, DLM_BEGIN_EXIT_DOMAIN_MSG, node);
634 spin_lock(&dlm->spinlock);
635 }
636 spin_unlock(&dlm->spinlock);
637 }
638
639 static void dlm_leave_domain(struct dlm_ctxt *dlm)
640 {
641 int node, clear_node, status;
642
643 /* At this point we've migrated away all our locks and won't
644 * accept mastership of new ones. The dlm is responsible for
645 * almost nothing now. We make sure not to confuse any joining
646 * nodes and then commence shutdown procedure. */
647
648 spin_lock(&dlm->spinlock);
649 /* Clear ourselves from the domain map */
650 clear_bit(dlm->node_num, dlm->domain_map);
651 while ((node = find_next_bit(dlm->domain_map, O2NM_MAX_NODES,
652 0)) < O2NM_MAX_NODES) {
653 /* Drop the dlm spinlock. This is safe wrt the domain_map.
654 * -nodes cannot be added now as the
655 * query_join_handlers knows to respond with OK_NO_MAP
656 * -we catch the right network errors if a node is
657 * removed from the map while we're sending him the
658 * exit message. */
659 spin_unlock(&dlm->spinlock);
660
661 clear_node = 1;
662
663 status = dlm_send_one_domain_exit(dlm, DLM_EXIT_DOMAIN_MSG,
664 node);
665 if (status < 0 &&
666 status != -ENOPROTOOPT &&
667 status != -ENOTCONN) {
668 mlog(ML_NOTICE, "Error %d sending domain exit message "
669 "to node %d\n", status, node);
670
671 /* Not sure what to do here but lets sleep for
672 * a bit in case this was a transient
673 * error... */
674 msleep(DLM_DOMAIN_BACKOFF_MS);
675 clear_node = 0;
676 }
677
678 spin_lock(&dlm->spinlock);
679 /* If we're not clearing the node bit then we intend
680 * to loop back around to try again. */
681 if (clear_node)
682 clear_bit(node, dlm->domain_map);
683 }
684 spin_unlock(&dlm->spinlock);
685 }
686
687 int dlm_joined(struct dlm_ctxt *dlm)
688 {
689 int ret = 0;
690
691 spin_lock(&dlm_domain_lock);
692
693 if (dlm->dlm_state == DLM_CTXT_JOINED)
694 ret = 1;
695
696 spin_unlock(&dlm_domain_lock);
697
698 return ret;
699 }
700
701 int dlm_shutting_down(struct dlm_ctxt *dlm)
702 {
703 int ret = 0;
704
705 spin_lock(&dlm_domain_lock);
706
707 if (dlm->dlm_state == DLM_CTXT_IN_SHUTDOWN)
708 ret = 1;
709
710 spin_unlock(&dlm_domain_lock);
711
712 return ret;
713 }
714
715 void dlm_unregister_domain(struct dlm_ctxt *dlm)
716 {
717 int leave = 0;
718 struct dlm_lock_resource *res;
719
720 spin_lock(&dlm_domain_lock);
721 BUG_ON(dlm->dlm_state != DLM_CTXT_JOINED);
722 BUG_ON(!dlm->num_joins);
723
724 dlm->num_joins--;
725 if (!dlm->num_joins) {
726 /* We mark it "in shutdown" now so new register
727 * requests wait until we've completely left the
728 * domain. Don't use DLM_CTXT_LEAVING yet as we still
729 * want new domain joins to communicate with us at
730 * least until we've completed migration of our
731 * resources. */
732 dlm->dlm_state = DLM_CTXT_IN_SHUTDOWN;
733 leave = 1;
734 }
735 spin_unlock(&dlm_domain_lock);
736
737 if (leave) {
738 mlog(0, "shutting down domain %s\n", dlm->name);
739 dlm_begin_exit_domain(dlm);
740
741 /* We changed dlm state, notify the thread */
742 dlm_kick_thread(dlm, NULL);
743
744 while (dlm_migrate_all_locks(dlm)) {
745 /* Give dlm_thread time to purge the lockres' */
746 msleep(500);
747 mlog(0, "%s: more migration to do\n", dlm->name);
748 }
749
750 /* This list should be empty. If not, print remaining lockres */
751 if (!list_empty(&dlm->tracking_list)) {
752 mlog(ML_ERROR, "Following lockres' are still on the "
753 "tracking list:\n");
754 list_for_each_entry(res, &dlm->tracking_list, tracking)
755 dlm_print_one_lock_resource(res);
756 }
757
758 dlm_mark_domain_leaving(dlm);
759 dlm_leave_domain(dlm);
760 printk(KERN_NOTICE "o2dlm: Leaving domain %s\n", dlm->name);
761 dlm_force_free_mles(dlm);
762 dlm_complete_dlm_shutdown(dlm);
763 }
764 dlm_put(dlm);
765 }
766 EXPORT_SYMBOL_GPL(dlm_unregister_domain);
767
768 static int dlm_query_join_proto_check(char *proto_type, int node,
769 struct dlm_protocol_version *ours,
770 struct dlm_protocol_version *request)
771 {
772 int rc;
773 struct dlm_protocol_version proto = *request;
774
775 if (!dlm_protocol_compare(ours, &proto)) {
776 mlog(0,
777 "node %u wanted to join with %s locking protocol "
778 "%u.%u, we respond with %u.%u\n",
779 node, proto_type,
780 request->pv_major,
781 request->pv_minor,
782 proto.pv_major, proto.pv_minor);
783 request->pv_minor = proto.pv_minor;
784 rc = 0;
785 } else {
786 mlog(ML_NOTICE,
787 "Node %u wanted to join with %s locking "
788 "protocol %u.%u, but we have %u.%u, disallowing\n",
789 node, proto_type,
790 request->pv_major,
791 request->pv_minor,
792 ours->pv_major,
793 ours->pv_minor);
794 rc = 1;
795 }
796
797 return rc;
798 }
799
800 /*
801 * struct dlm_query_join_packet is made up of four one-byte fields. They
802 * are effectively in big-endian order already. However, little-endian
803 * machines swap them before putting the packet on the wire (because
804 * query_join's response is a status, and that status is treated as a u32
805 * on the wire). Thus, a big-endian and little-endian machines will treat
806 * this structure differently.
807 *
808 * The solution is to have little-endian machines swap the structure when
809 * converting from the structure to the u32 representation. This will
810 * result in the structure having the correct format on the wire no matter
811 * the host endian format.
812 */
813 static void dlm_query_join_packet_to_wire(struct dlm_query_join_packet *packet,
814 u32 *wire)
815 {
816 union dlm_query_join_response response;
817
818 response.packet = *packet;
819 *wire = be32_to_cpu(response.intval);
820 }
821
822 static void dlm_query_join_wire_to_packet(u32 wire,
823 struct dlm_query_join_packet *packet)
824 {
825 union dlm_query_join_response response;
826
827 response.intval = cpu_to_be32(wire);
828 *packet = response.packet;
829 }
830
831 static int dlm_query_join_handler(struct o2net_msg *msg, u32 len, void *data,
832 void **ret_data)
833 {
834 struct dlm_query_join_request *query;
835 struct dlm_query_join_packet packet = {
836 .code = JOIN_DISALLOW,
837 };
838 struct dlm_ctxt *dlm = NULL;
839 u32 response;
840 u8 nodenum;
841
842 query = (struct dlm_query_join_request *) msg->buf;
843
844 mlog(0, "node %u wants to join domain %s\n", query->node_idx,
845 query->domain);
846
847 /*
848 * If heartbeat doesn't consider the node live, tell it
849 * to back off and try again. This gives heartbeat a chance
850 * to catch up.
851 */
852 if (!o2hb_check_node_heartbeating(query->node_idx)) {
853 mlog(0, "node %u is not in our live map yet\n",
854 query->node_idx);
855
856 packet.code = JOIN_DISALLOW;
857 goto respond;
858 }
859
860 packet.code = JOIN_OK_NO_MAP;
861
862 spin_lock(&dlm_domain_lock);
863 dlm = __dlm_lookup_domain_full(query->domain, query->name_len);
864 if (!dlm)
865 goto unlock_respond;
866
867 /*
868 * There is a small window where the joining node may not see the
869 * node(s) that just left but still part of the cluster. DISALLOW
870 * join request if joining node has different node map.
871 */
872 nodenum=0;
873 while (nodenum < O2NM_MAX_NODES) {
874 if (test_bit(nodenum, dlm->domain_map)) {
875 if (!byte_test_bit(nodenum, query->node_map)) {
876 mlog(0, "disallow join as node %u does not "
877 "have node %u in its nodemap\n",
878 query->node_idx, nodenum);
879 packet.code = JOIN_DISALLOW;
880 goto unlock_respond;
881 }
882 }
883 nodenum++;
884 }
885
886 /* Once the dlm ctxt is marked as leaving then we don't want
887 * to be put in someone's domain map.
888 * Also, explicitly disallow joining at certain troublesome
889 * times (ie. during recovery). */
890 if (dlm && dlm->dlm_state != DLM_CTXT_LEAVING) {
891 int bit = query->node_idx;
892 spin_lock(&dlm->spinlock);
893
894 if (dlm->dlm_state == DLM_CTXT_NEW &&
895 dlm->joining_node == DLM_LOCK_RES_OWNER_UNKNOWN) {
896 /*If this is a brand new context and we
897 * haven't started our join process yet, then
898 * the other node won the race. */
899 packet.code = JOIN_OK_NO_MAP;
900 } else if (dlm->joining_node != DLM_LOCK_RES_OWNER_UNKNOWN) {
901 /* Disallow parallel joins. */
902 packet.code = JOIN_DISALLOW;
903 } else if (dlm->reco.state & DLM_RECO_STATE_ACTIVE) {
904 mlog(0, "node %u trying to join, but recovery "
905 "is ongoing.\n", bit);
906 packet.code = JOIN_DISALLOW;
907 } else if (test_bit(bit, dlm->recovery_map)) {
908 mlog(0, "node %u trying to join, but it "
909 "still needs recovery.\n", bit);
910 packet.code = JOIN_DISALLOW;
911 } else if (test_bit(bit, dlm->domain_map)) {
912 mlog(0, "node %u trying to join, but it "
913 "is still in the domain! needs recovery?\n",
914 bit);
915 packet.code = JOIN_DISALLOW;
916 } else {
917 /* Alright we're fully a part of this domain
918 * so we keep some state as to who's joining
919 * and indicate to him that needs to be fixed
920 * up. */
921
922 /* Make sure we speak compatible locking protocols. */
923 if (dlm_query_join_proto_check("DLM", bit,
924 &dlm->dlm_locking_proto,
925 &query->dlm_proto)) {
926 packet.code = JOIN_PROTOCOL_MISMATCH;
927 } else if (dlm_query_join_proto_check("fs", bit,
928 &dlm->fs_locking_proto,
929 &query->fs_proto)) {
930 packet.code = JOIN_PROTOCOL_MISMATCH;
931 } else {
932 packet.dlm_minor = query->dlm_proto.pv_minor;
933 packet.fs_minor = query->fs_proto.pv_minor;
934 packet.code = JOIN_OK;
935 __dlm_set_joining_node(dlm, query->node_idx);
936 }
937 }
938
939 spin_unlock(&dlm->spinlock);
940 }
941 unlock_respond:
942 spin_unlock(&dlm_domain_lock);
943
944 respond:
945 mlog(0, "We respond with %u\n", packet.code);
946
947 dlm_query_join_packet_to_wire(&packet, &response);
948 return response;
949 }
950
951 static int dlm_assert_joined_handler(struct o2net_msg *msg, u32 len, void *data,
952 void **ret_data)
953 {
954 struct dlm_assert_joined *assert;
955 struct dlm_ctxt *dlm = NULL;
956
957 assert = (struct dlm_assert_joined *) msg->buf;
958
959 mlog(0, "node %u asserts join on domain %s\n", assert->node_idx,
960 assert->domain);
961
962 spin_lock(&dlm_domain_lock);
963 dlm = __dlm_lookup_domain_full(assert->domain, assert->name_len);
964 /* XXX should we consider no dlm ctxt an error? */
965 if (dlm) {
966 spin_lock(&dlm->spinlock);
967
968 /* Alright, this node has officially joined our
969 * domain. Set him in the map and clean up our
970 * leftover join state. */
971 BUG_ON(dlm->joining_node != assert->node_idx);
972 set_bit(assert->node_idx, dlm->domain_map);
973 clear_bit(assert->node_idx, dlm->exit_domain_map);
974 __dlm_set_joining_node(dlm, DLM_LOCK_RES_OWNER_UNKNOWN);
975
976 printk(KERN_NOTICE "o2dlm: Node %u joins domain %s ",
977 assert->node_idx, dlm->name);
978 __dlm_print_nodes(dlm);
979
980 /* notify anything attached to the heartbeat events */
981 dlm_hb_event_notify_attached(dlm, assert->node_idx, 1);
982
983 spin_unlock(&dlm->spinlock);
984 }
985 spin_unlock(&dlm_domain_lock);
986
987 return 0;
988 }
989
990 static int dlm_match_regions(struct dlm_ctxt *dlm,
991 struct dlm_query_region *qr,
992 char *local, int locallen)
993 {
994 char *remote = qr->qr_regions;
995 char *l, *r;
996 int localnr, i, j, foundit;
997 int status = 0;
998
999 if (!o2hb_global_heartbeat_active()) {
1000 if (qr->qr_numregions) {
1001 mlog(ML_ERROR, "Domain %s: Joining node %d has global "
1002 "heartbeat enabled but local node %d does not\n",
1003 qr->qr_domain, qr->qr_node, dlm->node_num);
1004 status = -EINVAL;
1005 }
1006 goto bail;
1007 }
1008
1009 if (o2hb_global_heartbeat_active() && !qr->qr_numregions) {
1010 mlog(ML_ERROR, "Domain %s: Local node %d has global "
1011 "heartbeat enabled but joining node %d does not\n",
1012 qr->qr_domain, dlm->node_num, qr->qr_node);
1013 status = -EINVAL;
1014 goto bail;
1015 }
1016
1017 r = remote;
1018 for (i = 0; i < qr->qr_numregions; ++i) {
1019 mlog(0, "Region %.*s\n", O2HB_MAX_REGION_NAME_LEN, r);
1020 r += O2HB_MAX_REGION_NAME_LEN;
1021 }
1022
1023 localnr = min(O2NM_MAX_REGIONS, locallen/O2HB_MAX_REGION_NAME_LEN);
1024 localnr = o2hb_get_all_regions(local, (u8)localnr);
1025
1026 /* compare local regions with remote */
1027 l = local;
1028 for (i = 0; i < localnr; ++i) {
1029 foundit = 0;
1030 r = remote;
1031 for (j = 0; j <= qr->qr_numregions; ++j) {
1032 if (!memcmp(l, r, O2HB_MAX_REGION_NAME_LEN)) {
1033 foundit = 1;
1034 break;
1035 }
1036 r += O2HB_MAX_REGION_NAME_LEN;
1037 }
1038 if (!foundit) {
1039 status = -EINVAL;
1040 mlog(ML_ERROR, "Domain %s: Region '%.*s' registered "
1041 "in local node %d but not in joining node %d\n",
1042 qr->qr_domain, O2HB_MAX_REGION_NAME_LEN, l,
1043 dlm->node_num, qr->qr_node);
1044 goto bail;
1045 }
1046 l += O2HB_MAX_REGION_NAME_LEN;
1047 }
1048
1049 /* compare remote with local regions */
1050 r = remote;
1051 for (i = 0; i < qr->qr_numregions; ++i) {
1052 foundit = 0;
1053 l = local;
1054 for (j = 0; j < localnr; ++j) {
1055 if (!memcmp(r, l, O2HB_MAX_REGION_NAME_LEN)) {
1056 foundit = 1;
1057 break;
1058 }
1059 l += O2HB_MAX_REGION_NAME_LEN;
1060 }
1061 if (!foundit) {
1062 status = -EINVAL;
1063 mlog(ML_ERROR, "Domain %s: Region '%.*s' registered "
1064 "in joining node %d but not in local node %d\n",
1065 qr->qr_domain, O2HB_MAX_REGION_NAME_LEN, r,
1066 qr->qr_node, dlm->node_num);
1067 goto bail;
1068 }
1069 r += O2HB_MAX_REGION_NAME_LEN;
1070 }
1071
1072 bail:
1073 return status;
1074 }
1075
1076 static int dlm_send_regions(struct dlm_ctxt *dlm, unsigned long *node_map)
1077 {
1078 struct dlm_query_region *qr = NULL;
1079 int status, ret = 0, i;
1080 char *p;
1081
1082 if (find_next_bit(node_map, O2NM_MAX_NODES, 0) >= O2NM_MAX_NODES)
1083 goto bail;
1084
1085 qr = kzalloc(sizeof(struct dlm_query_region), GFP_KERNEL);
1086 if (!qr) {
1087 ret = -ENOMEM;
1088 mlog_errno(ret);
1089 goto bail;
1090 }
1091
1092 qr->qr_node = dlm->node_num;
1093 qr->qr_namelen = strlen(dlm->name);
1094 memcpy(qr->qr_domain, dlm->name, qr->qr_namelen);
1095 /* if local hb, the numregions will be zero */
1096 if (o2hb_global_heartbeat_active())
1097 qr->qr_numregions = o2hb_get_all_regions(qr->qr_regions,
1098 O2NM_MAX_REGIONS);
1099
1100 p = qr->qr_regions;
1101 for (i = 0; i < qr->qr_numregions; ++i, p += O2HB_MAX_REGION_NAME_LEN)
1102 mlog(0, "Region %.*s\n", O2HB_MAX_REGION_NAME_LEN, p);
1103
1104 i = -1;
1105 while ((i = find_next_bit(node_map, O2NM_MAX_NODES,
1106 i + 1)) < O2NM_MAX_NODES) {
1107 if (i == dlm->node_num)
1108 continue;
1109
1110 mlog(0, "Sending regions to node %d\n", i);
1111
1112 ret = o2net_send_message(DLM_QUERY_REGION, DLM_MOD_KEY, qr,
1113 sizeof(struct dlm_query_region),
1114 i, &status);
1115 if (ret >= 0)
1116 ret = status;
1117 if (ret) {
1118 mlog(ML_ERROR, "Region mismatch %d, node %d\n",
1119 ret, i);
1120 break;
1121 }
1122 }
1123
1124 bail:
1125 kfree(qr);
1126 return ret;
1127 }
1128
1129 static int dlm_query_region_handler(struct o2net_msg *msg, u32 len,
1130 void *data, void **ret_data)
1131 {
1132 struct dlm_query_region *qr;
1133 struct dlm_ctxt *dlm = NULL;
1134 char *local = NULL;
1135 int status = 0;
1136 int locked = 0;
1137
1138 qr = (struct dlm_query_region *) msg->buf;
1139
1140 mlog(0, "Node %u queries hb regions on domain %s\n", qr->qr_node,
1141 qr->qr_domain);
1142
1143 /* buffer used in dlm_mast_regions() */
1144 local = kmalloc(sizeof(qr->qr_regions), GFP_KERNEL);
1145 if (!local) {
1146 status = -ENOMEM;
1147 goto bail;
1148 }
1149
1150 status = -EINVAL;
1151
1152 spin_lock(&dlm_domain_lock);
1153 dlm = __dlm_lookup_domain_full(qr->qr_domain, qr->qr_namelen);
1154 if (!dlm) {
1155 mlog(ML_ERROR, "Node %d queried hb regions on domain %s "
1156 "before join domain\n", qr->qr_node, qr->qr_domain);
1157 goto bail;
1158 }
1159
1160 spin_lock(&dlm->spinlock);
1161 locked = 1;
1162 if (dlm->joining_node != qr->qr_node) {
1163 mlog(ML_ERROR, "Node %d queried hb regions on domain %s "
1164 "but joining node is %d\n", qr->qr_node, qr->qr_domain,
1165 dlm->joining_node);
1166 goto bail;
1167 }
1168
1169 /* Support for global heartbeat was added in 1.1 */
1170 if (dlm->dlm_locking_proto.pv_major == 1 &&
1171 dlm->dlm_locking_proto.pv_minor == 0) {
1172 mlog(ML_ERROR, "Node %d queried hb regions on domain %s "
1173 "but active dlm protocol is %d.%d\n", qr->qr_node,
1174 qr->qr_domain, dlm->dlm_locking_proto.pv_major,
1175 dlm->dlm_locking_proto.pv_minor);
1176 goto bail;
1177 }
1178
1179 status = dlm_match_regions(dlm, qr, local, sizeof(qr->qr_regions));
1180
1181 bail:
1182 if (locked)
1183 spin_unlock(&dlm->spinlock);
1184 spin_unlock(&dlm_domain_lock);
1185
1186 kfree(local);
1187
1188 return status;
1189 }
1190
1191 static int dlm_match_nodes(struct dlm_ctxt *dlm, struct dlm_query_nodeinfo *qn)
1192 {
1193 struct o2nm_node *local;
1194 struct dlm_node_info *remote;
1195 int i, j;
1196 int status = 0;
1197
1198 for (j = 0; j < qn->qn_numnodes; ++j)
1199 mlog(0, "Node %3d, %pI4:%u\n", qn->qn_nodes[j].ni_nodenum,
1200 &(qn->qn_nodes[j].ni_ipv4_address),
1201 ntohs(qn->qn_nodes[j].ni_ipv4_port));
1202
1203 for (i = 0; i < O2NM_MAX_NODES && !status; ++i) {
1204 local = o2nm_get_node_by_num(i);
1205 remote = NULL;
1206 for (j = 0; j < qn->qn_numnodes; ++j) {
1207 if (qn->qn_nodes[j].ni_nodenum == i) {
1208 remote = &(qn->qn_nodes[j]);
1209 break;
1210 }
1211 }
1212
1213 if (!local && !remote)
1214 continue;
1215
1216 if ((local && !remote) || (!local && remote))
1217 status = -EINVAL;
1218
1219 if (!status &&
1220 ((remote->ni_nodenum != local->nd_num) ||
1221 (remote->ni_ipv4_port != local->nd_ipv4_port) ||
1222 (remote->ni_ipv4_address != local->nd_ipv4_address)))
1223 status = -EINVAL;
1224
1225 if (status) {
1226 if (remote && !local)
1227 mlog(ML_ERROR, "Domain %s: Node %d (%pI4:%u) "
1228 "registered in joining node %d but not in "
1229 "local node %d\n", qn->qn_domain,
1230 remote->ni_nodenum,
1231 &(remote->ni_ipv4_address),
1232 ntohs(remote->ni_ipv4_port),
1233 qn->qn_nodenum, dlm->node_num);
1234 if (local && !remote)
1235 mlog(ML_ERROR, "Domain %s: Node %d (%pI4:%u) "
1236 "registered in local node %d but not in "
1237 "joining node %d\n", qn->qn_domain,
1238 local->nd_num, &(local->nd_ipv4_address),
1239 ntohs(local->nd_ipv4_port),
1240 dlm->node_num, qn->qn_nodenum);
1241 BUG_ON((!local && !remote));
1242 }
1243
1244 if (local)
1245 o2nm_node_put(local);
1246 }
1247
1248 return status;
1249 }
1250
1251 static int dlm_send_nodeinfo(struct dlm_ctxt *dlm, unsigned long *node_map)
1252 {
1253 struct dlm_query_nodeinfo *qn = NULL;
1254 struct o2nm_node *node;
1255 int ret = 0, status, count, i;
1256
1257 if (find_next_bit(node_map, O2NM_MAX_NODES, 0) >= O2NM_MAX_NODES)
1258 goto bail;
1259
1260 qn = kzalloc(sizeof(struct dlm_query_nodeinfo), GFP_KERNEL);
1261 if (!qn) {
1262 ret = -ENOMEM;
1263 mlog_errno(ret);
1264 goto bail;
1265 }
1266
1267 for (i = 0, count = 0; i < O2NM_MAX_NODES; ++i) {
1268 node = o2nm_get_node_by_num(i);
1269 if (!node)
1270 continue;
1271 qn->qn_nodes[count].ni_nodenum = node->nd_num;
1272 qn->qn_nodes[count].ni_ipv4_port = node->nd_ipv4_port;
1273 qn->qn_nodes[count].ni_ipv4_address = node->nd_ipv4_address;
1274 mlog(0, "Node %3d, %pI4:%u\n", node->nd_num,
1275 &(node->nd_ipv4_address), ntohs(node->nd_ipv4_port));
1276 ++count;
1277 o2nm_node_put(node);
1278 }
1279
1280 qn->qn_nodenum = dlm->node_num;
1281 qn->qn_numnodes = count;
1282 qn->qn_namelen = strlen(dlm->name);
1283 memcpy(qn->qn_domain, dlm->name, qn->qn_namelen);
1284
1285 i = -1;
1286 while ((i = find_next_bit(node_map, O2NM_MAX_NODES,
1287 i + 1)) < O2NM_MAX_NODES) {
1288 if (i == dlm->node_num)
1289 continue;
1290
1291 mlog(0, "Sending nodeinfo to node %d\n", i);
1292
1293 ret = o2net_send_message(DLM_QUERY_NODEINFO, DLM_MOD_KEY,
1294 qn, sizeof(struct dlm_query_nodeinfo),
1295 i, &status);
1296 if (ret >= 0)
1297 ret = status;
1298 if (ret) {
1299 mlog(ML_ERROR, "node mismatch %d, node %d\n", ret, i);
1300 break;
1301 }
1302 }
1303
1304 bail:
1305 kfree(qn);
1306 return ret;
1307 }
1308
1309 static int dlm_query_nodeinfo_handler(struct o2net_msg *msg, u32 len,
1310 void *data, void **ret_data)
1311 {
1312 struct dlm_query_nodeinfo *qn;
1313 struct dlm_ctxt *dlm = NULL;
1314 int locked = 0, status = -EINVAL;
1315
1316 qn = (struct dlm_query_nodeinfo *) msg->buf;
1317
1318 mlog(0, "Node %u queries nodes on domain %s\n", qn->qn_nodenum,
1319 qn->qn_domain);
1320
1321 spin_lock(&dlm_domain_lock);
1322 dlm = __dlm_lookup_domain_full(qn->qn_domain, qn->qn_namelen);
1323 if (!dlm) {
1324 mlog(ML_ERROR, "Node %d queried nodes on domain %s before "
1325 "join domain\n", qn->qn_nodenum, qn->qn_domain);
1326 goto bail;
1327 }
1328
1329 spin_lock(&dlm->spinlock);
1330 locked = 1;
1331 if (dlm->joining_node != qn->qn_nodenum) {
1332 mlog(ML_ERROR, "Node %d queried nodes on domain %s but "
1333 "joining node is %d\n", qn->qn_nodenum, qn->qn_domain,
1334 dlm->joining_node);
1335 goto bail;
1336 }
1337
1338 /* Support for node query was added in 1.1 */
1339 if (dlm->dlm_locking_proto.pv_major == 1 &&
1340 dlm->dlm_locking_proto.pv_minor == 0) {
1341 mlog(ML_ERROR, "Node %d queried nodes on domain %s "
1342 "but active dlm protocol is %d.%d\n", qn->qn_nodenum,
1343 qn->qn_domain, dlm->dlm_locking_proto.pv_major,
1344 dlm->dlm_locking_proto.pv_minor);
1345 goto bail;
1346 }
1347
1348 status = dlm_match_nodes(dlm, qn);
1349
1350 bail:
1351 if (locked)
1352 spin_unlock(&dlm->spinlock);
1353 spin_unlock(&dlm_domain_lock);
1354
1355 return status;
1356 }
1357
1358 static int dlm_cancel_join_handler(struct o2net_msg *msg, u32 len, void *data,
1359 void **ret_data)
1360 {
1361 struct dlm_cancel_join *cancel;
1362 struct dlm_ctxt *dlm = NULL;
1363
1364 cancel = (struct dlm_cancel_join *) msg->buf;
1365
1366 mlog(0, "node %u cancels join on domain %s\n", cancel->node_idx,
1367 cancel->domain);
1368
1369 spin_lock(&dlm_domain_lock);
1370 dlm = __dlm_lookup_domain_full(cancel->domain, cancel->name_len);
1371
1372 if (dlm) {
1373 spin_lock(&dlm->spinlock);
1374
1375 /* Yikes, this guy wants to cancel his join. No
1376 * problem, we simply cleanup our join state. */
1377 BUG_ON(dlm->joining_node != cancel->node_idx);
1378 __dlm_set_joining_node(dlm, DLM_LOCK_RES_OWNER_UNKNOWN);
1379
1380 spin_unlock(&dlm->spinlock);
1381 }
1382 spin_unlock(&dlm_domain_lock);
1383
1384 return 0;
1385 }
1386
1387 static int dlm_send_one_join_cancel(struct dlm_ctxt *dlm,
1388 unsigned int node)
1389 {
1390 int status;
1391 struct dlm_cancel_join cancel_msg;
1392
1393 memset(&cancel_msg, 0, sizeof(cancel_msg));
1394 cancel_msg.node_idx = dlm->node_num;
1395 cancel_msg.name_len = strlen(dlm->name);
1396 memcpy(cancel_msg.domain, dlm->name, cancel_msg.name_len);
1397
1398 status = o2net_send_message(DLM_CANCEL_JOIN_MSG, DLM_MOD_KEY,
1399 &cancel_msg, sizeof(cancel_msg), node,
1400 NULL);
1401 if (status < 0) {
1402 mlog(ML_ERROR, "Error %d when sending message %u (key 0x%x) to "
1403 "node %u\n", status, DLM_CANCEL_JOIN_MSG, DLM_MOD_KEY,
1404 node);
1405 goto bail;
1406 }
1407
1408 bail:
1409 return status;
1410 }
1411
1412 /* map_size should be in bytes. */
1413 static int dlm_send_join_cancels(struct dlm_ctxt *dlm,
1414 unsigned long *node_map,
1415 unsigned int map_size)
1416 {
1417 int status, tmpstat;
1418 unsigned int node;
1419
1420 if (map_size != (BITS_TO_LONGS(O2NM_MAX_NODES) *
1421 sizeof(unsigned long))) {
1422 mlog(ML_ERROR,
1423 "map_size %u != BITS_TO_LONGS(O2NM_MAX_NODES) %u\n",
1424 map_size, (unsigned)BITS_TO_LONGS(O2NM_MAX_NODES));
1425 return -EINVAL;
1426 }
1427
1428 status = 0;
1429 node = -1;
1430 while ((node = find_next_bit(node_map, O2NM_MAX_NODES,
1431 node + 1)) < O2NM_MAX_NODES) {
1432 if (node == dlm->node_num)
1433 continue;
1434
1435 tmpstat = dlm_send_one_join_cancel(dlm, node);
1436 if (tmpstat) {
1437 mlog(ML_ERROR, "Error return %d cancelling join on "
1438 "node %d\n", tmpstat, node);
1439 if (!status)
1440 status = tmpstat;
1441 }
1442 }
1443
1444 if (status)
1445 mlog_errno(status);
1446 return status;
1447 }
1448
1449 static int dlm_request_join(struct dlm_ctxt *dlm,
1450 int node,
1451 enum dlm_query_join_response_code *response)
1452 {
1453 int status;
1454 struct dlm_query_join_request join_msg;
1455 struct dlm_query_join_packet packet;
1456 u32 join_resp;
1457
1458 mlog(0, "querying node %d\n", node);
1459
1460 memset(&join_msg, 0, sizeof(join_msg));
1461 join_msg.node_idx = dlm->node_num;
1462 join_msg.name_len = strlen(dlm->name);
1463 memcpy(join_msg.domain, dlm->name, join_msg.name_len);
1464 join_msg.dlm_proto = dlm->dlm_locking_proto;
1465 join_msg.fs_proto = dlm->fs_locking_proto;
1466
1467 /* copy live node map to join message */
1468 byte_copymap(join_msg.node_map, dlm->live_nodes_map, O2NM_MAX_NODES);
1469
1470 status = o2net_send_message(DLM_QUERY_JOIN_MSG, DLM_MOD_KEY, &join_msg,
1471 sizeof(join_msg), node, &join_resp);
1472 if (status < 0 && status != -ENOPROTOOPT) {
1473 mlog(ML_ERROR, "Error %d when sending message %u (key 0x%x) to "
1474 "node %u\n", status, DLM_QUERY_JOIN_MSG, DLM_MOD_KEY,
1475 node);
1476 goto bail;
1477 }
1478 dlm_query_join_wire_to_packet(join_resp, &packet);
1479
1480 /* -ENOPROTOOPT from the net code means the other side isn't
1481 listening for our message type -- that's fine, it means
1482 his dlm isn't up, so we can consider him a 'yes' but not
1483 joined into the domain. */
1484 if (status == -ENOPROTOOPT) {
1485 status = 0;
1486 *response = JOIN_OK_NO_MAP;
1487 } else if (packet.code == JOIN_DISALLOW ||
1488 packet.code == JOIN_OK_NO_MAP) {
1489 *response = packet.code;
1490 } else if (packet.code == JOIN_PROTOCOL_MISMATCH) {
1491 mlog(ML_NOTICE,
1492 "This node requested DLM locking protocol %u.%u and "
1493 "filesystem locking protocol %u.%u. At least one of "
1494 "the protocol versions on node %d is not compatible, "
1495 "disconnecting\n",
1496 dlm->dlm_locking_proto.pv_major,
1497 dlm->dlm_locking_proto.pv_minor,
1498 dlm->fs_locking_proto.pv_major,
1499 dlm->fs_locking_proto.pv_minor,
1500 node);
1501 status = -EPROTO;
1502 *response = packet.code;
1503 } else if (packet.code == JOIN_OK) {
1504 *response = packet.code;
1505 /* Use the same locking protocol as the remote node */
1506 dlm->dlm_locking_proto.pv_minor = packet.dlm_minor;
1507 dlm->fs_locking_proto.pv_minor = packet.fs_minor;
1508 mlog(0,
1509 "Node %d responds JOIN_OK with DLM locking protocol "
1510 "%u.%u and fs locking protocol %u.%u\n",
1511 node,
1512 dlm->dlm_locking_proto.pv_major,
1513 dlm->dlm_locking_proto.pv_minor,
1514 dlm->fs_locking_proto.pv_major,
1515 dlm->fs_locking_proto.pv_minor);
1516 } else {
1517 status = -EINVAL;
1518 mlog(ML_ERROR, "invalid response %d from node %u\n",
1519 packet.code, node);
1520 }
1521
1522 mlog(0, "status %d, node %d response is %d\n", status, node,
1523 *response);
1524
1525 bail:
1526 return status;
1527 }
1528
1529 static int dlm_send_one_join_assert(struct dlm_ctxt *dlm,
1530 unsigned int node)
1531 {
1532 int status;
1533 struct dlm_assert_joined assert_msg;
1534
1535 mlog(0, "Sending join assert to node %u\n", node);
1536
1537 memset(&assert_msg, 0, sizeof(assert_msg));
1538 assert_msg.node_idx = dlm->node_num;
1539 assert_msg.name_len = strlen(dlm->name);
1540 memcpy(assert_msg.domain, dlm->name, assert_msg.name_len);
1541
1542 status = o2net_send_message(DLM_ASSERT_JOINED_MSG, DLM_MOD_KEY,
1543 &assert_msg, sizeof(assert_msg), node,
1544 NULL);
1545 if (status < 0)
1546 mlog(ML_ERROR, "Error %d when sending message %u (key 0x%x) to "
1547 "node %u\n", status, DLM_ASSERT_JOINED_MSG, DLM_MOD_KEY,
1548 node);
1549
1550 return status;
1551 }
1552
1553 static void dlm_send_join_asserts(struct dlm_ctxt *dlm,
1554 unsigned long *node_map)
1555 {
1556 int status, node, live;
1557
1558 status = 0;
1559 node = -1;
1560 while ((node = find_next_bit(node_map, O2NM_MAX_NODES,
1561 node + 1)) < O2NM_MAX_NODES) {
1562 if (node == dlm->node_num)
1563 continue;
1564
1565 do {
1566 /* It is very important that this message be
1567 * received so we spin until either the node
1568 * has died or it gets the message. */
1569 status = dlm_send_one_join_assert(dlm, node);
1570
1571 spin_lock(&dlm->spinlock);
1572 live = test_bit(node, dlm->live_nodes_map);
1573 spin_unlock(&dlm->spinlock);
1574
1575 if (status) {
1576 mlog(ML_ERROR, "Error return %d asserting "
1577 "join on node %d\n", status, node);
1578
1579 /* give us some time between errors... */
1580 if (live)
1581 msleep(DLM_DOMAIN_BACKOFF_MS);
1582 }
1583 } while (status && live);
1584 }
1585 }
1586
1587 struct domain_join_ctxt {
1588 unsigned long live_map[BITS_TO_LONGS(O2NM_MAX_NODES)];
1589 unsigned long yes_resp_map[BITS_TO_LONGS(O2NM_MAX_NODES)];
1590 };
1591
1592 static int dlm_should_restart_join(struct dlm_ctxt *dlm,
1593 struct domain_join_ctxt *ctxt,
1594 enum dlm_query_join_response_code response)
1595 {
1596 int ret;
1597
1598 if (response == JOIN_DISALLOW) {
1599 mlog(0, "Latest response of disallow -- should restart\n");
1600 return 1;
1601 }
1602
1603 spin_lock(&dlm->spinlock);
1604 /* For now, we restart the process if the node maps have
1605 * changed at all */
1606 ret = memcmp(ctxt->live_map, dlm->live_nodes_map,
1607 sizeof(dlm->live_nodes_map));
1608 spin_unlock(&dlm->spinlock);
1609
1610 if (ret)
1611 mlog(0, "Node maps changed -- should restart\n");
1612
1613 return ret;
1614 }
1615
1616 static int dlm_try_to_join_domain(struct dlm_ctxt *dlm)
1617 {
1618 int status = 0, tmpstat, node;
1619 struct domain_join_ctxt *ctxt;
1620 enum dlm_query_join_response_code response = JOIN_DISALLOW;
1621
1622 mlog(0, "%p", dlm);
1623
1624 ctxt = kzalloc(sizeof(*ctxt), GFP_KERNEL);
1625 if (!ctxt) {
1626 status = -ENOMEM;
1627 mlog_errno(status);
1628 goto bail;
1629 }
1630
1631 /* group sem locking should work for us here -- we're already
1632 * registered for heartbeat events so filling this should be
1633 * atomic wrt getting those handlers called. */
1634 o2hb_fill_node_map(dlm->live_nodes_map, sizeof(dlm->live_nodes_map));
1635
1636 spin_lock(&dlm->spinlock);
1637 memcpy(ctxt->live_map, dlm->live_nodes_map, sizeof(ctxt->live_map));
1638
1639 __dlm_set_joining_node(dlm, dlm->node_num);
1640
1641 spin_unlock(&dlm->spinlock);
1642
1643 node = -1;
1644 while ((node = find_next_bit(ctxt->live_map, O2NM_MAX_NODES,
1645 node + 1)) < O2NM_MAX_NODES) {
1646 if (node == dlm->node_num)
1647 continue;
1648
1649 status = dlm_request_join(dlm, node, &response);
1650 if (status < 0) {
1651 mlog_errno(status);
1652 goto bail;
1653 }
1654
1655 /* Ok, either we got a response or the node doesn't have a
1656 * dlm up. */
1657 if (response == JOIN_OK)
1658 set_bit(node, ctxt->yes_resp_map);
1659
1660 if (dlm_should_restart_join(dlm, ctxt, response)) {
1661 status = -EAGAIN;
1662 goto bail;
1663 }
1664 }
1665
1666 mlog(0, "Yay, done querying nodes!\n");
1667
1668 /* Yay, everyone agree's we can join the domain. My domain is
1669 * comprised of all nodes who were put in the
1670 * yes_resp_map. Copy that into our domain map and send a join
1671 * assert message to clean up everyone elses state. */
1672 spin_lock(&dlm->spinlock);
1673 memcpy(dlm->domain_map, ctxt->yes_resp_map,
1674 sizeof(ctxt->yes_resp_map));
1675 set_bit(dlm->node_num, dlm->domain_map);
1676 spin_unlock(&dlm->spinlock);
1677
1678 /* Support for global heartbeat and node info was added in 1.1 */
1679 if (dlm->dlm_locking_proto.pv_major > 1 ||
1680 dlm->dlm_locking_proto.pv_minor > 0) {
1681 status = dlm_send_nodeinfo(dlm, ctxt->yes_resp_map);
1682 if (status) {
1683 mlog_errno(status);
1684 goto bail;
1685 }
1686 status = dlm_send_regions(dlm, ctxt->yes_resp_map);
1687 if (status) {
1688 mlog_errno(status);
1689 goto bail;
1690 }
1691 }
1692
1693 dlm_send_join_asserts(dlm, ctxt->yes_resp_map);
1694
1695 /* Joined state *must* be set before the joining node
1696 * information, otherwise the query_join handler may read no
1697 * current joiner but a state of NEW and tell joining nodes
1698 * we're not in the domain. */
1699 spin_lock(&dlm_domain_lock);
1700 dlm->dlm_state = DLM_CTXT_JOINED;
1701 dlm->num_joins++;
1702 spin_unlock(&dlm_domain_lock);
1703
1704 bail:
1705 spin_lock(&dlm->spinlock);
1706 __dlm_set_joining_node(dlm, DLM_LOCK_RES_OWNER_UNKNOWN);
1707 if (!status) {
1708 printk(KERN_NOTICE "o2dlm: Joining domain %s ", dlm->name);
1709 __dlm_print_nodes(dlm);
1710 }
1711 spin_unlock(&dlm->spinlock);
1712
1713 if (ctxt) {
1714 /* Do we need to send a cancel message to any nodes? */
1715 if (status < 0) {
1716 tmpstat = dlm_send_join_cancels(dlm,
1717 ctxt->yes_resp_map,
1718 sizeof(ctxt->yes_resp_map));
1719 if (tmpstat < 0)
1720 mlog_errno(tmpstat);
1721 }
1722 kfree(ctxt);
1723 }
1724
1725 mlog(0, "returning %d\n", status);
1726 return status;
1727 }
1728
1729 static void dlm_unregister_domain_handlers(struct dlm_ctxt *dlm)
1730 {
1731 o2hb_unregister_callback(dlm->name, &dlm->dlm_hb_up);
1732 o2hb_unregister_callback(dlm->name, &dlm->dlm_hb_down);
1733 o2net_unregister_handler_list(&dlm->dlm_domain_handlers);
1734 }
1735
1736 static int dlm_register_domain_handlers(struct dlm_ctxt *dlm)
1737 {
1738 int status;
1739
1740 mlog(0, "registering handlers.\n");
1741
1742 o2hb_setup_callback(&dlm->dlm_hb_down, O2HB_NODE_DOWN_CB,
1743 dlm_hb_node_down_cb, dlm, DLM_HB_NODE_DOWN_PRI);
1744 status = o2hb_register_callback(dlm->name, &dlm->dlm_hb_down);
1745 if (status)
1746 goto bail;
1747
1748 o2hb_setup_callback(&dlm->dlm_hb_up, O2HB_NODE_UP_CB,
1749 dlm_hb_node_up_cb, dlm, DLM_HB_NODE_UP_PRI);
1750 status = o2hb_register_callback(dlm->name, &dlm->dlm_hb_up);
1751 if (status)
1752 goto bail;
1753
1754 status = o2net_register_handler(DLM_MASTER_REQUEST_MSG, dlm->key,
1755 sizeof(struct dlm_master_request),
1756 dlm_master_request_handler,
1757 dlm, NULL, &dlm->dlm_domain_handlers);
1758 if (status)
1759 goto bail;
1760
1761 status = o2net_register_handler(DLM_ASSERT_MASTER_MSG, dlm->key,
1762 sizeof(struct dlm_assert_master),
1763 dlm_assert_master_handler,
1764 dlm, dlm_assert_master_post_handler,
1765 &dlm->dlm_domain_handlers);
1766 if (status)
1767 goto bail;
1768
1769 status = o2net_register_handler(DLM_CREATE_LOCK_MSG, dlm->key,
1770 sizeof(struct dlm_create_lock),
1771 dlm_create_lock_handler,
1772 dlm, NULL, &dlm->dlm_domain_handlers);
1773 if (status)
1774 goto bail;
1775
1776 status = o2net_register_handler(DLM_CONVERT_LOCK_MSG, dlm->key,
1777 DLM_CONVERT_LOCK_MAX_LEN,
1778 dlm_convert_lock_handler,
1779 dlm, NULL, &dlm->dlm_domain_handlers);
1780 if (status)
1781 goto bail;
1782
1783 status = o2net_register_handler(DLM_UNLOCK_LOCK_MSG, dlm->key,
1784 DLM_UNLOCK_LOCK_MAX_LEN,
1785 dlm_unlock_lock_handler,
1786 dlm, NULL, &dlm->dlm_domain_handlers);
1787 if (status)
1788 goto bail;
1789
1790 status = o2net_register_handler(DLM_PROXY_AST_MSG, dlm->key,
1791 DLM_PROXY_AST_MAX_LEN,
1792 dlm_proxy_ast_handler,
1793 dlm, NULL, &dlm->dlm_domain_handlers);
1794 if (status)
1795 goto bail;
1796
1797 status = o2net_register_handler(DLM_EXIT_DOMAIN_MSG, dlm->key,
1798 sizeof(struct dlm_exit_domain),
1799 dlm_exit_domain_handler,
1800 dlm, NULL, &dlm->dlm_domain_handlers);
1801 if (status)
1802 goto bail;
1803
1804 status = o2net_register_handler(DLM_DEREF_LOCKRES_MSG, dlm->key,
1805 sizeof(struct dlm_deref_lockres),
1806 dlm_deref_lockres_handler,
1807 dlm, NULL, &dlm->dlm_domain_handlers);
1808 if (status)
1809 goto bail;
1810
1811 status = o2net_register_handler(DLM_MIGRATE_REQUEST_MSG, dlm->key,
1812 sizeof(struct dlm_migrate_request),
1813 dlm_migrate_request_handler,
1814 dlm, NULL, &dlm->dlm_domain_handlers);
1815 if (status)
1816 goto bail;
1817
1818 status = o2net_register_handler(DLM_MIG_LOCKRES_MSG, dlm->key,
1819 DLM_MIG_LOCKRES_MAX_LEN,
1820 dlm_mig_lockres_handler,
1821 dlm, NULL, &dlm->dlm_domain_handlers);
1822 if (status)
1823 goto bail;
1824
1825 status = o2net_register_handler(DLM_MASTER_REQUERY_MSG, dlm->key,
1826 sizeof(struct dlm_master_requery),
1827 dlm_master_requery_handler,
1828 dlm, NULL, &dlm->dlm_domain_handlers);
1829 if (status)
1830 goto bail;
1831
1832 status = o2net_register_handler(DLM_LOCK_REQUEST_MSG, dlm->key,
1833 sizeof(struct dlm_lock_request),
1834 dlm_request_all_locks_handler,
1835 dlm, NULL, &dlm->dlm_domain_handlers);
1836 if (status)
1837 goto bail;
1838
1839 status = o2net_register_handler(DLM_RECO_DATA_DONE_MSG, dlm->key,
1840 sizeof(struct dlm_reco_data_done),
1841 dlm_reco_data_done_handler,
1842 dlm, NULL, &dlm->dlm_domain_handlers);
1843 if (status)
1844 goto bail;
1845
1846 status = o2net_register_handler(DLM_BEGIN_RECO_MSG, dlm->key,
1847 sizeof(struct dlm_begin_reco),
1848 dlm_begin_reco_handler,
1849 dlm, NULL, &dlm->dlm_domain_handlers);
1850 if (status)
1851 goto bail;
1852
1853 status = o2net_register_handler(DLM_FINALIZE_RECO_MSG, dlm->key,
1854 sizeof(struct dlm_finalize_reco),
1855 dlm_finalize_reco_handler,
1856 dlm, NULL, &dlm->dlm_domain_handlers);
1857 if (status)
1858 goto bail;
1859
1860 status = o2net_register_handler(DLM_BEGIN_EXIT_DOMAIN_MSG, dlm->key,
1861 sizeof(struct dlm_exit_domain),
1862 dlm_begin_exit_domain_handler,
1863 dlm, NULL, &dlm->dlm_domain_handlers);
1864 if (status)
1865 goto bail;
1866
1867 bail:
1868 if (status)
1869 dlm_unregister_domain_handlers(dlm);
1870
1871 return status;
1872 }
1873
1874 static int dlm_join_domain(struct dlm_ctxt *dlm)
1875 {
1876 int status;
1877 unsigned int backoff;
1878 unsigned int total_backoff = 0;
1879
1880 BUG_ON(!dlm);
1881
1882 mlog(0, "Join domain %s\n", dlm->name);
1883
1884 status = dlm_register_domain_handlers(dlm);
1885 if (status) {
1886 mlog_errno(status);
1887 goto bail;
1888 }
1889
1890 status = dlm_debug_init(dlm);
1891 if (status < 0) {
1892 mlog_errno(status);
1893 goto bail;
1894 }
1895
1896 status = dlm_launch_thread(dlm);
1897 if (status < 0) {
1898 mlog_errno(status);
1899 goto bail;
1900 }
1901
1902 status = dlm_launch_recovery_thread(dlm);
1903 if (status < 0) {
1904 mlog_errno(status);
1905 goto bail;
1906 }
1907
1908 dlm->dlm_worker = create_singlethread_workqueue("dlm_wq");
1909 if (!dlm->dlm_worker) {
1910 status = -ENOMEM;
1911 mlog_errno(status);
1912 goto bail;
1913 }
1914
1915 do {
1916 status = dlm_try_to_join_domain(dlm);
1917
1918 /* If we're racing another node to the join, then we
1919 * need to back off temporarily and let them
1920 * complete. */
1921 #define DLM_JOIN_TIMEOUT_MSECS 90000
1922 if (status == -EAGAIN) {
1923 if (signal_pending(current)) {
1924 status = -ERESTARTSYS;
1925 goto bail;
1926 }
1927
1928 if (total_backoff >
1929 msecs_to_jiffies(DLM_JOIN_TIMEOUT_MSECS)) {
1930 status = -ERESTARTSYS;
1931 mlog(ML_NOTICE, "Timed out joining dlm domain "
1932 "%s after %u msecs\n", dlm->name,
1933 jiffies_to_msecs(total_backoff));
1934 goto bail;
1935 }
1936
1937 /*
1938 * <chip> After you!
1939 * <dale> No, after you!
1940 * <chip> I insist!
1941 * <dale> But you first!
1942 * ...
1943 */
1944 backoff = (unsigned int)(jiffies & 0x3);
1945 backoff *= DLM_DOMAIN_BACKOFF_MS;
1946 total_backoff += backoff;
1947 mlog(0, "backoff %d\n", backoff);
1948 msleep(backoff);
1949 }
1950 } while (status == -EAGAIN);
1951
1952 if (status < 0) {
1953 mlog_errno(status);
1954 goto bail;
1955 }
1956
1957 status = 0;
1958 bail:
1959 wake_up(&dlm_domain_events);
1960
1961 if (status) {
1962 dlm_unregister_domain_handlers(dlm);
1963 dlm_debug_shutdown(dlm);
1964 dlm_complete_thread(dlm);
1965 dlm_complete_recovery_thread(dlm);
1966 dlm_destroy_dlm_worker(dlm);
1967 }
1968
1969 return status;
1970 }
1971
1972 static struct dlm_ctxt *dlm_alloc_ctxt(const char *domain,
1973 u32 key)
1974 {
1975 int i;
1976 int ret;
1977 struct dlm_ctxt *dlm = NULL;
1978
1979 dlm = kzalloc(sizeof(*dlm), GFP_KERNEL);
1980 if (!dlm) {
1981 mlog_errno(-ENOMEM);
1982 goto leave;
1983 }
1984
1985 dlm->name = kstrdup(domain, GFP_KERNEL);
1986 if (dlm->name == NULL) {
1987 mlog_errno(-ENOMEM);
1988 kfree(dlm);
1989 dlm = NULL;
1990 goto leave;
1991 }
1992
1993 dlm->lockres_hash = (struct hlist_head **)dlm_alloc_pagevec(DLM_HASH_PAGES);
1994 if (!dlm->lockres_hash) {
1995 mlog_errno(-ENOMEM);
1996 kfree(dlm->name);
1997 kfree(dlm);
1998 dlm = NULL;
1999 goto leave;
2000 }
2001
2002 for (i = 0; i < DLM_HASH_BUCKETS; i++)
2003 INIT_HLIST_HEAD(dlm_lockres_hash(dlm, i));
2004
2005 dlm->master_hash = (struct hlist_head **)
2006 dlm_alloc_pagevec(DLM_HASH_PAGES);
2007 if (!dlm->master_hash) {
2008 mlog_errno(-ENOMEM);
2009 dlm_free_pagevec((void **)dlm->lockres_hash, DLM_HASH_PAGES);
2010 kfree(dlm->name);
2011 kfree(dlm);
2012 dlm = NULL;
2013 goto leave;
2014 }
2015
2016 for (i = 0; i < DLM_HASH_BUCKETS; i++)
2017 INIT_HLIST_HEAD(dlm_master_hash(dlm, i));
2018
2019 dlm->key = key;
2020 dlm->node_num = o2nm_this_node();
2021
2022 ret = dlm_create_debugfs_subroot(dlm);
2023 if (ret < 0) {
2024 dlm_free_pagevec((void **)dlm->master_hash, DLM_HASH_PAGES);
2025 dlm_free_pagevec((void **)dlm->lockres_hash, DLM_HASH_PAGES);
2026 kfree(dlm->name);
2027 kfree(dlm);
2028 dlm = NULL;
2029 goto leave;
2030 }
2031
2032 spin_lock_init(&dlm->spinlock);
2033 spin_lock_init(&dlm->master_lock);
2034 spin_lock_init(&dlm->ast_lock);
2035 spin_lock_init(&dlm->track_lock);
2036 INIT_LIST_HEAD(&dlm->list);
2037 INIT_LIST_HEAD(&dlm->dirty_list);
2038 INIT_LIST_HEAD(&dlm->reco.resources);
2039 INIT_LIST_HEAD(&dlm->reco.received);
2040 INIT_LIST_HEAD(&dlm->reco.node_data);
2041 INIT_LIST_HEAD(&dlm->purge_list);
2042 INIT_LIST_HEAD(&dlm->dlm_domain_handlers);
2043 INIT_LIST_HEAD(&dlm->tracking_list);
2044 dlm->reco.state = 0;
2045
2046 INIT_LIST_HEAD(&dlm->pending_asts);
2047 INIT_LIST_HEAD(&dlm->pending_basts);
2048
2049 mlog(0, "dlm->recovery_map=%p, &(dlm->recovery_map[0])=%p\n",
2050 dlm->recovery_map, &(dlm->recovery_map[0]));
2051
2052 memset(dlm->recovery_map, 0, sizeof(dlm->recovery_map));
2053 memset(dlm->live_nodes_map, 0, sizeof(dlm->live_nodes_map));
2054 memset(dlm->domain_map, 0, sizeof(dlm->domain_map));
2055
2056 dlm->dlm_thread_task = NULL;
2057 dlm->dlm_reco_thread_task = NULL;
2058 dlm->dlm_worker = NULL;
2059 init_waitqueue_head(&dlm->dlm_thread_wq);
2060 init_waitqueue_head(&dlm->dlm_reco_thread_wq);
2061 init_waitqueue_head(&dlm->reco.event);
2062 init_waitqueue_head(&dlm->ast_wq);
2063 init_waitqueue_head(&dlm->migration_wq);
2064 INIT_LIST_HEAD(&dlm->mle_hb_events);
2065
2066 dlm->joining_node = DLM_LOCK_RES_OWNER_UNKNOWN;
2067 init_waitqueue_head(&dlm->dlm_join_events);
2068
2069 dlm->reco.new_master = O2NM_INVALID_NODE_NUM;
2070 dlm->reco.dead_node = O2NM_INVALID_NODE_NUM;
2071
2072 atomic_set(&dlm->res_tot_count, 0);
2073 atomic_set(&dlm->res_cur_count, 0);
2074 for (i = 0; i < DLM_MLE_NUM_TYPES; ++i) {
2075 atomic_set(&dlm->mle_tot_count[i], 0);
2076 atomic_set(&dlm->mle_cur_count[i], 0);
2077 }
2078
2079 spin_lock_init(&dlm->work_lock);
2080 INIT_LIST_HEAD(&dlm->work_list);
2081 INIT_WORK(&dlm->dispatched_work, dlm_dispatch_work);
2082
2083 kref_init(&dlm->dlm_refs);
2084 dlm->dlm_state = DLM_CTXT_NEW;
2085
2086 INIT_LIST_HEAD(&dlm->dlm_eviction_callbacks);
2087
2088 mlog(0, "context init: refcount %u\n",
2089 atomic_read(&dlm->dlm_refs.refcount));
2090
2091 leave:
2092 return dlm;
2093 }
2094
2095 /*
2096 * Compare a requested locking protocol version against the current one.
2097 *
2098 * If the major numbers are different, they are incompatible.
2099 * If the current minor is greater than the request, they are incompatible.
2100 * If the current minor is less than or equal to the request, they are
2101 * compatible, and the requester should run at the current minor version.
2102 */
2103 static int dlm_protocol_compare(struct dlm_protocol_version *existing,
2104 struct dlm_protocol_version *request)
2105 {
2106 if (existing->pv_major != request->pv_major)
2107 return 1;
2108
2109 if (existing->pv_minor > request->pv_minor)
2110 return 1;
2111
2112 if (existing->pv_minor < request->pv_minor)
2113 request->pv_minor = existing->pv_minor;
2114
2115 return 0;
2116 }
2117
2118 /*
2119 * dlm_register_domain: one-time setup per "domain".
2120 *
2121 * The filesystem passes in the requested locking version via proto.
2122 * If registration was successful, proto will contain the negotiated
2123 * locking protocol.
2124 */
2125 struct dlm_ctxt * dlm_register_domain(const char *domain,
2126 u32 key,
2127 struct dlm_protocol_version *fs_proto)
2128 {
2129 int ret;
2130 struct dlm_ctxt *dlm = NULL;
2131 struct dlm_ctxt *new_ctxt = NULL;
2132
2133 if (strlen(domain) >= O2NM_MAX_NAME_LEN) {
2134 ret = -ENAMETOOLONG;
2135 mlog(ML_ERROR, "domain name length too long\n");
2136 goto leave;
2137 }
2138
2139 mlog(0, "register called for domain \"%s\"\n", domain);
2140
2141 retry:
2142 dlm = NULL;
2143 if (signal_pending(current)) {
2144 ret = -ERESTARTSYS;
2145 mlog_errno(ret);
2146 goto leave;
2147 }
2148
2149 spin_lock(&dlm_domain_lock);
2150
2151 dlm = __dlm_lookup_domain(domain);
2152 if (dlm) {
2153 if (dlm->dlm_state != DLM_CTXT_JOINED) {
2154 spin_unlock(&dlm_domain_lock);
2155
2156 mlog(0, "This ctxt is not joined yet!\n");
2157 wait_event_interruptible(dlm_domain_events,
2158 dlm_wait_on_domain_helper(
2159 domain));
2160 goto retry;
2161 }
2162
2163 if (dlm_protocol_compare(&dlm->fs_locking_proto, fs_proto)) {
2164 spin_unlock(&dlm_domain_lock);
2165 mlog(ML_ERROR,
2166 "Requested locking protocol version is not "
2167 "compatible with already registered domain "
2168 "\"%s\"\n", domain);
2169 ret = -EPROTO;
2170 goto leave;
2171 }
2172
2173 __dlm_get(dlm);
2174 dlm->num_joins++;
2175
2176 spin_unlock(&dlm_domain_lock);
2177
2178 ret = 0;
2179 goto leave;
2180 }
2181
2182 /* doesn't exist */
2183 if (!new_ctxt) {
2184 spin_unlock(&dlm_domain_lock);
2185
2186 new_ctxt = dlm_alloc_ctxt(domain, key);
2187 if (new_ctxt)
2188 goto retry;
2189
2190 ret = -ENOMEM;
2191 mlog_errno(ret);
2192 goto leave;
2193 }
2194
2195 /* a little variable switch-a-roo here... */
2196 dlm = new_ctxt;
2197 new_ctxt = NULL;
2198
2199 /* add the new domain */
2200 list_add_tail(&dlm->list, &dlm_domains);
2201 spin_unlock(&dlm_domain_lock);
2202
2203 /*
2204 * Pass the locking protocol version into the join. If the join
2205 * succeeds, it will have the negotiated protocol set.
2206 */
2207 dlm->dlm_locking_proto = dlm_protocol;
2208 dlm->fs_locking_proto = *fs_proto;
2209
2210 ret = dlm_join_domain(dlm);
2211 if (ret) {
2212 mlog_errno(ret);
2213 dlm_put(dlm);
2214 goto leave;
2215 }
2216
2217 /* Tell the caller what locking protocol we negotiated */
2218 *fs_proto = dlm->fs_locking_proto;
2219
2220 ret = 0;
2221 leave:
2222 if (new_ctxt)
2223 dlm_free_ctxt_mem(new_ctxt);
2224
2225 if (ret < 0)
2226 dlm = ERR_PTR(ret);
2227
2228 return dlm;
2229 }
2230 EXPORT_SYMBOL_GPL(dlm_register_domain);
2231
2232 static LIST_HEAD(dlm_join_handlers);
2233
2234 static void dlm_unregister_net_handlers(void)
2235 {
2236 o2net_unregister_handler_list(&dlm_join_handlers);
2237 }
2238
2239 static int dlm_register_net_handlers(void)
2240 {
2241 int status = 0;
2242
2243 status = o2net_register_handler(DLM_QUERY_JOIN_MSG, DLM_MOD_KEY,
2244 sizeof(struct dlm_query_join_request),
2245 dlm_query_join_handler,
2246 NULL, NULL, &dlm_join_handlers);
2247 if (status)
2248 goto bail;
2249
2250 status = o2net_register_handler(DLM_ASSERT_JOINED_MSG, DLM_MOD_KEY,
2251 sizeof(struct dlm_assert_joined),
2252 dlm_assert_joined_handler,
2253 NULL, NULL, &dlm_join_handlers);
2254 if (status)
2255 goto bail;
2256
2257 status = o2net_register_handler(DLM_CANCEL_JOIN_MSG, DLM_MOD_KEY,
2258 sizeof(struct dlm_cancel_join),
2259 dlm_cancel_join_handler,
2260 NULL, NULL, &dlm_join_handlers);
2261 if (status)
2262 goto bail;
2263
2264 status = o2net_register_handler(DLM_QUERY_REGION, DLM_MOD_KEY,
2265 sizeof(struct dlm_query_region),
2266 dlm_query_region_handler,
2267 NULL, NULL, &dlm_join_handlers);
2268
2269 if (status)
2270 goto bail;
2271
2272 status = o2net_register_handler(DLM_QUERY_NODEINFO, DLM_MOD_KEY,
2273 sizeof(struct dlm_query_nodeinfo),
2274 dlm_query_nodeinfo_handler,
2275 NULL, NULL, &dlm_join_handlers);
2276 bail:
2277 if (status < 0)
2278 dlm_unregister_net_handlers();
2279
2280 return status;
2281 }
2282
2283 /* Domain eviction callback handling.
2284 *
2285 * The file system requires notification of node death *before* the
2286 * dlm completes it's recovery work, otherwise it may be able to
2287 * acquire locks on resources requiring recovery. Since the dlm can
2288 * evict a node from it's domain *before* heartbeat fires, a similar
2289 * mechanism is required. */
2290
2291 /* Eviction is not expected to happen often, so a per-domain lock is
2292 * not necessary. Eviction callbacks are allowed to sleep for short
2293 * periods of time. */
2294 static DECLARE_RWSEM(dlm_callback_sem);
2295
2296 void dlm_fire_domain_eviction_callbacks(struct dlm_ctxt *dlm,
2297 int node_num)
2298 {
2299 struct list_head *iter;
2300 struct dlm_eviction_cb *cb;
2301
2302 down_read(&dlm_callback_sem);
2303 list_for_each(iter, &dlm->dlm_eviction_callbacks) {
2304 cb = list_entry(iter, struct dlm_eviction_cb, ec_item);
2305
2306 cb->ec_func(node_num, cb->ec_data);
2307 }
2308 up_read(&dlm_callback_sem);
2309 }
2310
2311 void dlm_setup_eviction_cb(struct dlm_eviction_cb *cb,
2312 dlm_eviction_func *f,
2313 void *data)
2314 {
2315 INIT_LIST_HEAD(&cb->ec_item);
2316 cb->ec_func = f;
2317 cb->ec_data = data;
2318 }
2319 EXPORT_SYMBOL_GPL(dlm_setup_eviction_cb);
2320
2321 void dlm_register_eviction_cb(struct dlm_ctxt *dlm,
2322 struct dlm_eviction_cb *cb)
2323 {
2324 down_write(&dlm_callback_sem);
2325 list_add_tail(&cb->ec_item, &dlm->dlm_eviction_callbacks);
2326 up_write(&dlm_callback_sem);
2327 }
2328 EXPORT_SYMBOL_GPL(dlm_register_eviction_cb);
2329
2330 void dlm_unregister_eviction_cb(struct dlm_eviction_cb *cb)
2331 {
2332 down_write(&dlm_callback_sem);
2333 list_del_init(&cb->ec_item);
2334 up_write(&dlm_callback_sem);
2335 }
2336 EXPORT_SYMBOL_GPL(dlm_unregister_eviction_cb);
2337
2338 static int __init dlm_init(void)
2339 {
2340 int status;
2341
2342 dlm_print_version();
2343
2344 status = dlm_init_mle_cache();
2345 if (status) {
2346 mlog(ML_ERROR, "Could not create o2dlm_mle slabcache\n");
2347 goto error;
2348 }
2349
2350 status = dlm_init_master_caches();
2351 if (status) {
2352 mlog(ML_ERROR, "Could not create o2dlm_lockres and "
2353 "o2dlm_lockname slabcaches\n");
2354 goto error;
2355 }
2356
2357 status = dlm_init_lock_cache();
2358 if (status) {
2359 mlog(ML_ERROR, "Count not create o2dlm_lock slabcache\n");
2360 goto error;
2361 }
2362
2363 status = dlm_register_net_handlers();
2364 if (status) {
2365 mlog(ML_ERROR, "Unable to register network handlers\n");
2366 goto error;
2367 }
2368
2369 status = dlm_create_debugfs_root();
2370 if (status)
2371 goto error;
2372
2373 return 0;
2374 error:
2375 dlm_unregister_net_handlers();
2376 dlm_destroy_lock_cache();
2377 dlm_destroy_master_caches();
2378 dlm_destroy_mle_cache();
2379 return -1;
2380 }
2381
2382 static void __exit dlm_exit (void)
2383 {
2384 dlm_destroy_debugfs_root();
2385 dlm_unregister_net_handlers();
2386 dlm_destroy_lock_cache();
2387 dlm_destroy_master_caches();
2388 dlm_destroy_mle_cache();
2389 }
2390
2391 MODULE_AUTHOR("Oracle");
2392 MODULE_LICENSE("GPL");
2393
2394 module_init(dlm_init);
2395 module_exit(dlm_exit);
Linux with added FPC-III support