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Merge tag 'regmap-fix-v4.9-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git...
[linux/fpc-iii.git] / fs / ocfs2 / dlm / dlmdomain.c
blob733e4e79c8e25f02e3a3af1ad562049d32742cbc
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 #define MLOG_MASK_PREFIX (ML_DLM|ML_DLM_DOMAIN)
47 #include "cluster/masklog.h"
48
49 /*
50 * ocfs2 node maps are array of long int, which limits to send them freely
51 * across the wire due to endianness issues. To workaround this, we convert
52 * long ints to byte arrays. Following 3 routines are helper functions to
53 * set/test/copy bits within those array of bytes
54 */
55 static inline void byte_set_bit(u8 nr, u8 map[])
56 {
57 map[nr >> 3] |= (1UL << (nr & 7));
58 }
59
60 static inline int byte_test_bit(u8 nr, u8 map[])
61 {
62 return ((1UL << (nr & 7)) & (map[nr >> 3])) != 0;
63 }
64
65 static inline void byte_copymap(u8 dmap[], unsigned long smap[],
66 unsigned int sz)
67 {
68 unsigned int nn;
69
70 if (!sz)
71 return;
72
73 memset(dmap, 0, ((sz + 7) >> 3));
74 for (nn = 0 ; nn < sz; nn++)
75 if (test_bit(nn, smap))
76 byte_set_bit(nn, dmap);
77 }
78
79 static void dlm_free_pagevec(void **vec, int pages)
80 {
81 while (pages--)
82 free_page((unsigned long)vec[pages]);
83 kfree(vec);
84 }
85
86 static void **dlm_alloc_pagevec(int pages)
87 {
88 void **vec = kmalloc(pages * sizeof(void *), GFP_KERNEL);
89 int i;
90
91 if (!vec)
92 return NULL;
93
94 for (i = 0; i < pages; i++)
95 if (!(vec[i] = (void *)__get_free_page(GFP_KERNEL)))
96 goto out_free;
97
98 mlog(0, "Allocated DLM hash pagevec; %d pages (%lu expected), %lu buckets per page\n",
99 pages, (unsigned long)DLM_HASH_PAGES,
100 (unsigned long)DLM_BUCKETS_PER_PAGE);
101 return vec;
102 out_free:
103 dlm_free_pagevec(vec, i);
104 return NULL;
105 }
106
107 /*
108 *
109 * spinlock lock ordering: if multiple locks are needed, obey this ordering:
110 * dlm_domain_lock
111 * struct dlm_ctxt->spinlock
112 * struct dlm_lock_resource->spinlock
113 * struct dlm_ctxt->master_lock
114 * struct dlm_ctxt->ast_lock
115 * dlm_master_list_entry->spinlock
116 * dlm_lock->spinlock
117 *
118 */
119
120 DEFINE_SPINLOCK(dlm_domain_lock);
121 LIST_HEAD(dlm_domains);
122 static DECLARE_WAIT_QUEUE_HEAD(dlm_domain_events);
123
124 /*
125 * The supported protocol version for DLM communication. Running domains
126 * will have a negotiated version with the same major number and a minor
127 * number equal or smaller. The dlm_ctxt->dlm_locking_proto field should
128 * be used to determine what a running domain is actually using.
129 *
130 * New in version 1.1:
131 * - Message DLM_QUERY_REGION added to support global heartbeat
132 * - Message DLM_QUERY_NODEINFO added to allow online node removes
133 * New in version 1.2:
134 * - Message DLM_BEGIN_EXIT_DOMAIN_MSG added to mark start of exit domain
135 * New in version 1.3:
136 * - Message DLM_DEREF_LOCKRES_DONE added to inform non-master that the
137 * refmap is cleared
138 */
139 static const struct dlm_protocol_version dlm_protocol = {
140 .pv_major = 1,
141 .pv_minor = 3,
142 };
143
144 #define DLM_DOMAIN_BACKOFF_MS 200
145
146 static int dlm_query_join_handler(struct o2net_msg *msg, u32 len, void *data,
147 void **ret_data);
148 static int dlm_assert_joined_handler(struct o2net_msg *msg, u32 len, void *data,
149 void **ret_data);
150 static int dlm_cancel_join_handler(struct o2net_msg *msg, u32 len, void *data,
151 void **ret_data);
152 static int dlm_query_region_handler(struct o2net_msg *msg, u32 len,
153 void *data, void **ret_data);
154 static int dlm_exit_domain_handler(struct o2net_msg *msg, u32 len, void *data,
155 void **ret_data);
156 static int dlm_protocol_compare(struct dlm_protocol_version *existing,
157 struct dlm_protocol_version *request);
158
159 static void dlm_unregister_domain_handlers(struct dlm_ctxt *dlm);
160
161 void __dlm_unhash_lockres(struct dlm_ctxt *dlm, struct dlm_lock_resource *res)
162 {
163 if (hlist_unhashed(&res->hash_node))
164 return;
165
166 mlog(0, "%s: Unhash res %.*s\n", dlm->name, res->lockname.len,
167 res->lockname.name);
168 hlist_del_init(&res->hash_node);
169 dlm_lockres_put(res);
170 }
171
172 void __dlm_insert_lockres(struct dlm_ctxt *dlm, struct dlm_lock_resource *res)
173 {
174 struct hlist_head *bucket;
175
176 assert_spin_locked(&dlm->spinlock);
177
178 bucket = dlm_lockres_hash(dlm, res->lockname.hash);
179
180 /* get a reference for our hashtable */
181 dlm_lockres_get(res);
182
183 hlist_add_head(&res->hash_node, bucket);
184
185 mlog(0, "%s: Hash res %.*s\n", dlm->name, res->lockname.len,
186 res->lockname.name);
187 }
188
189 struct dlm_lock_resource * __dlm_lookup_lockres_full(struct dlm_ctxt *dlm,
190 const char *name,
191 unsigned int len,
192 unsigned int hash)
193 {
194 struct hlist_head *bucket;
195 struct dlm_lock_resource *res;
196
197 mlog(0, "%.*s\n", len, name);
198
199 assert_spin_locked(&dlm->spinlock);
200
201 bucket = dlm_lockres_hash(dlm, hash);
202
203 hlist_for_each_entry(res, bucket, hash_node) {
204 if (res->lockname.name[0] != name[0])
205 continue;
206 if (unlikely(res->lockname.len != len))
207 continue;
208 if (memcmp(res->lockname.name + 1, name + 1, len - 1))
209 continue;
210 dlm_lockres_get(res);
211 return res;
212 }
213 return NULL;
214 }
215
216 /* intended to be called by functions which do not care about lock
217 * resources which are being purged (most net _handler functions).
218 * this will return NULL for any lock resource which is found but
219 * currently in the process of dropping its mastery reference.
220 * use __dlm_lookup_lockres_full when you need the lock resource
221 * regardless (e.g. dlm_get_lock_resource) */
222 struct dlm_lock_resource * __dlm_lookup_lockres(struct dlm_ctxt *dlm,
223 const char *name,
224 unsigned int len,
225 unsigned int hash)
226 {
227 struct dlm_lock_resource *res = NULL;
228
229 mlog(0, "%.*s\n", len, name);
230
231 assert_spin_locked(&dlm->spinlock);
232
233 res = __dlm_lookup_lockres_full(dlm, name, len, hash);
234 if (res) {
235 spin_lock(&res->spinlock);
236 if (res->state & DLM_LOCK_RES_DROPPING_REF) {
237 spin_unlock(&res->spinlock);
238 dlm_lockres_put(res);
239 return NULL;
240 }
241 spin_unlock(&res->spinlock);
242 }
243
244 return res;
245 }
246
247 struct dlm_lock_resource * dlm_lookup_lockres(struct dlm_ctxt *dlm,
248 const char *name,
249 unsigned int len)
250 {
251 struct dlm_lock_resource *res;
252 unsigned int hash = dlm_lockid_hash(name, len);
253
254 spin_lock(&dlm->spinlock);
255 res = __dlm_lookup_lockres(dlm, name, len, hash);
256 spin_unlock(&dlm->spinlock);
257 return res;
258 }
259
260 static struct dlm_ctxt * __dlm_lookup_domain_full(const char *domain, int len)
261 {
262 struct dlm_ctxt *tmp;
263
264 assert_spin_locked(&dlm_domain_lock);
265
266 /* tmp->name here is always NULL terminated,
267 * but domain may not be! */
268 list_for_each_entry(tmp, &dlm_domains, list) {
269 if (strlen(tmp->name) == len &&
270 memcmp(tmp->name, domain, len)==0)
271 return tmp;
272 }
273
274 return NULL;
275 }
276
277 /* For null terminated domain strings ONLY */
278 static struct dlm_ctxt * __dlm_lookup_domain(const char *domain)
279 {
280 assert_spin_locked(&dlm_domain_lock);
281
282 return __dlm_lookup_domain_full(domain, strlen(domain));
283 }
284
285
286 /* returns true on one of two conditions:
287 * 1) the domain does not exist
288 * 2) the domain exists and it's state is "joined" */
289 static int dlm_wait_on_domain_helper(const char *domain)
290 {
291 int ret = 0;
292 struct dlm_ctxt *tmp = NULL;
293
294 spin_lock(&dlm_domain_lock);
295
296 tmp = __dlm_lookup_domain(domain);
297 if (!tmp)
298 ret = 1;
299 else if (tmp->dlm_state == DLM_CTXT_JOINED)
300 ret = 1;
301
302 spin_unlock(&dlm_domain_lock);
303 return ret;
304 }
305
306 static void dlm_free_ctxt_mem(struct dlm_ctxt *dlm)
307 {
308 dlm_destroy_debugfs_subroot(dlm);
309
310 if (dlm->lockres_hash)
311 dlm_free_pagevec((void **)dlm->lockres_hash, DLM_HASH_PAGES);
312
313 if (dlm->master_hash)
314 dlm_free_pagevec((void **)dlm->master_hash, DLM_HASH_PAGES);
315
316 kfree(dlm->name);
317 kfree(dlm);
318 }
319
320 /* A little strange - this function will be called while holding
321 * dlm_domain_lock and is expected to be holding it on the way out. We
322 * will however drop and reacquire it multiple times */
323 static void dlm_ctxt_release(struct kref *kref)
324 {
325 struct dlm_ctxt *dlm;
326
327 dlm = container_of(kref, struct dlm_ctxt, dlm_refs);
328
329 BUG_ON(dlm->num_joins);
330 BUG_ON(dlm->dlm_state == DLM_CTXT_JOINED);
331
332 /* we may still be in the list if we hit an error during join. */
333 list_del_init(&dlm->list);
334
335 spin_unlock(&dlm_domain_lock);
336
337 mlog(0, "freeing memory from domain %s\n", dlm->name);
338
339 wake_up(&dlm_domain_events);
340
341 dlm_free_ctxt_mem(dlm);
342
343 spin_lock(&dlm_domain_lock);
344 }
345
346 void dlm_put(struct dlm_ctxt *dlm)
347 {
348 spin_lock(&dlm_domain_lock);
349 kref_put(&dlm->dlm_refs, dlm_ctxt_release);
350 spin_unlock(&dlm_domain_lock);
351 }
352
353 static void __dlm_get(struct dlm_ctxt *dlm)
354 {
355 kref_get(&dlm->dlm_refs);
356 }
357
358 /* given a questionable reference to a dlm object, gets a reference if
359 * it can find it in the list, otherwise returns NULL in which case
360 * you shouldn't trust your pointer. */
361 struct dlm_ctxt *dlm_grab(struct dlm_ctxt *dlm)
362 {
363 struct dlm_ctxt *target;
364 struct dlm_ctxt *ret = NULL;
365
366 spin_lock(&dlm_domain_lock);
367
368 list_for_each_entry(target, &dlm_domains, list) {
369 if (target == dlm) {
370 __dlm_get(target);
371 ret = target;
372 break;
373 }
374 }
375
376 spin_unlock(&dlm_domain_lock);
377
378 return ret;
379 }
380
381 int dlm_domain_fully_joined(struct dlm_ctxt *dlm)
382 {
383 int ret;
384
385 spin_lock(&dlm_domain_lock);
386 ret = (dlm->dlm_state == DLM_CTXT_JOINED) ||
387 (dlm->dlm_state == DLM_CTXT_IN_SHUTDOWN);
388 spin_unlock(&dlm_domain_lock);
389
390 return ret;
391 }
392
393 static void dlm_destroy_dlm_worker(struct dlm_ctxt *dlm)
394 {
395 if (dlm->dlm_worker) {
396 flush_workqueue(dlm->dlm_worker);
397 destroy_workqueue(dlm->dlm_worker);
398 dlm->dlm_worker = NULL;
399 }
400 }
401
402 static void dlm_complete_dlm_shutdown(struct dlm_ctxt *dlm)
403 {
404 dlm_unregister_domain_handlers(dlm);
405 dlm_debug_shutdown(dlm);
406 dlm_complete_thread(dlm);
407 dlm_complete_recovery_thread(dlm);
408 dlm_destroy_dlm_worker(dlm);
409
410 /* We've left the domain. Now we can take ourselves out of the
411 * list and allow the kref stuff to help us free the
412 * memory. */
413 spin_lock(&dlm_domain_lock);
414 list_del_init(&dlm->list);
415 spin_unlock(&dlm_domain_lock);
416
417 /* Wake up anyone waiting for us to remove this domain */
418 wake_up(&dlm_domain_events);
419 }
420
421 static int dlm_migrate_all_locks(struct dlm_ctxt *dlm)
422 {
423 int i, num, n, ret = 0;
424 struct dlm_lock_resource *res;
425 struct hlist_node *iter;
426 struct hlist_head *bucket;
427 int dropped;
428
429 mlog(0, "Migrating locks from domain %s\n", dlm->name);
430
431 num = 0;
432 spin_lock(&dlm->spinlock);
433 for (i = 0; i < DLM_HASH_BUCKETS; i++) {
434 redo_bucket:
435 n = 0;
436 bucket = dlm_lockres_hash(dlm, i);
437 iter = bucket->first;
438 while (iter) {
439 n++;
440 res = hlist_entry(iter, struct dlm_lock_resource,
441 hash_node);
442 dlm_lockres_get(res);
443 /* migrate, if necessary. this will drop the dlm
444 * spinlock and retake it if it does migration. */
445 dropped = dlm_empty_lockres(dlm, res);
446
447 spin_lock(&res->spinlock);
448 if (dropped)
449 __dlm_lockres_calc_usage(dlm, res);
450 else
451 iter = res->hash_node.next;
452 spin_unlock(&res->spinlock);
453
454 dlm_lockres_put(res);
455
456 if (dropped) {
457 cond_resched_lock(&dlm->spinlock);
458 goto redo_bucket;
459 }
460 }
461 cond_resched_lock(&dlm->spinlock);
462 num += n;
463 }
464 spin_unlock(&dlm->spinlock);
465 wake_up(&dlm->dlm_thread_wq);
466
467 /* let the dlm thread take care of purging, keep scanning until
468 * nothing remains in the hash */
469 if (num) {
470 mlog(0, "%s: %d lock resources in hash last pass\n",
471 dlm->name, num);
472 ret = -EAGAIN;
473 }
474 mlog(0, "DONE Migrating locks from domain %s\n", dlm->name);
475 return ret;
476 }
477
478 static int dlm_no_joining_node(struct dlm_ctxt *dlm)
479 {
480 int ret;
481
482 spin_lock(&dlm->spinlock);
483 ret = dlm->joining_node == DLM_LOCK_RES_OWNER_UNKNOWN;
484 spin_unlock(&dlm->spinlock);
485
486 return ret;
487 }
488
489 static int dlm_begin_exit_domain_handler(struct o2net_msg *msg, u32 len,
490 void *data, void **ret_data)
491 {
492 struct dlm_ctxt *dlm = data;
493 unsigned int node;
494 struct dlm_exit_domain *exit_msg = (struct dlm_exit_domain *) msg->buf;
495
496 if (!dlm_grab(dlm))
497 return 0;
498
499 node = exit_msg->node_idx;
500 mlog(0, "%s: Node %u sent a begin exit domain message\n", dlm->name, node);
501
502 spin_lock(&dlm->spinlock);
503 set_bit(node, dlm->exit_domain_map);
504 spin_unlock(&dlm->spinlock);
505
506 dlm_put(dlm);
507
508 return 0;
509 }
510
511 static void dlm_mark_domain_leaving(struct dlm_ctxt *dlm)
512 {
513 /* Yikes, a double spinlock! I need domain_lock for the dlm
514 * state and the dlm spinlock for join state... Sorry! */
515 again:
516 spin_lock(&dlm_domain_lock);
517 spin_lock(&dlm->spinlock);
518
519 if (dlm->joining_node != DLM_LOCK_RES_OWNER_UNKNOWN) {
520 mlog(0, "Node %d is joining, we wait on it.\n",
521 dlm->joining_node);
522 spin_unlock(&dlm->spinlock);
523 spin_unlock(&dlm_domain_lock);
524
525 wait_event(dlm->dlm_join_events, dlm_no_joining_node(dlm));
526 goto again;
527 }
528
529 dlm->dlm_state = DLM_CTXT_LEAVING;
530 spin_unlock(&dlm->spinlock);
531 spin_unlock(&dlm_domain_lock);
532 }
533
534 static void __dlm_print_nodes(struct dlm_ctxt *dlm)
535 {
536 int node = -1, num = 0;
537
538 assert_spin_locked(&dlm->spinlock);
539
540 printk("( ");
541 while ((node = find_next_bit(dlm->domain_map, O2NM_MAX_NODES,
542 node + 1)) < O2NM_MAX_NODES) {
543 printk("%d ", node);
544 ++num;
545 }
546 printk(") %u nodes\n", num);
547 }
548
549 static int dlm_exit_domain_handler(struct o2net_msg *msg, u32 len, void *data,
550 void **ret_data)
551 {
552 struct dlm_ctxt *dlm = data;
553 unsigned int node;
554 struct dlm_exit_domain *exit_msg = (struct dlm_exit_domain *) msg->buf;
555
556 mlog(0, "%p %u %p", msg, len, data);
557
558 if (!dlm_grab(dlm))
559 return 0;
560
561 node = exit_msg->node_idx;
562
563 spin_lock(&dlm->spinlock);
564 clear_bit(node, dlm->domain_map);
565 clear_bit(node, dlm->exit_domain_map);
566 printk(KERN_NOTICE "o2dlm: Node %u leaves domain %s ", node, dlm->name);
567 __dlm_print_nodes(dlm);
568
569 /* notify anything attached to the heartbeat events */
570 dlm_hb_event_notify_attached(dlm, node, 0);
571
572 spin_unlock(&dlm->spinlock);
573
574 dlm_put(dlm);
575
576 return 0;
577 }
578
579 static int dlm_send_one_domain_exit(struct dlm_ctxt *dlm, u32 msg_type,
580 unsigned int node)
581 {
582 int status;
583 struct dlm_exit_domain leave_msg;
584
585 mlog(0, "%s: Sending domain exit message %u to node %u\n", dlm->name,
586 msg_type, node);
587
588 memset(&leave_msg, 0, sizeof(leave_msg));
589 leave_msg.node_idx = dlm->node_num;
590
591 status = o2net_send_message(msg_type, dlm->key, &leave_msg,
592 sizeof(leave_msg), node, NULL);
593 if (status < 0)
594 mlog(ML_ERROR, "Error %d sending domain exit message %u "
595 "to node %u on domain %s\n", status, msg_type, node,
596 dlm->name);
597
598 return status;
599 }
600
601 static void dlm_begin_exit_domain(struct dlm_ctxt *dlm)
602 {
603 int node = -1;
604
605 /* Support for begin exit domain was added in 1.2 */
606 if (dlm->dlm_locking_proto.pv_major == 1 &&
607 dlm->dlm_locking_proto.pv_minor < 2)
608 return;
609
610 /*
611 * Unlike DLM_EXIT_DOMAIN_MSG, DLM_BEGIN_EXIT_DOMAIN_MSG is purely
612 * informational. Meaning if a node does not receive the message,
613 * so be it.
614 */
615 spin_lock(&dlm->spinlock);
616 while (1) {
617 node = find_next_bit(dlm->domain_map, O2NM_MAX_NODES, node + 1);
618 if (node >= O2NM_MAX_NODES)
619 break;
620 if (node == dlm->node_num)
621 continue;
622
623 spin_unlock(&dlm->spinlock);
624 dlm_send_one_domain_exit(dlm, DLM_BEGIN_EXIT_DOMAIN_MSG, node);
625 spin_lock(&dlm->spinlock);
626 }
627 spin_unlock(&dlm->spinlock);
628 }
629
630 static void dlm_leave_domain(struct dlm_ctxt *dlm)
631 {
632 int node, clear_node, status;
633
634 /* At this point we've migrated away all our locks and won't
635 * accept mastership of new ones. The dlm is responsible for
636 * almost nothing now. We make sure not to confuse any joining
637 * nodes and then commence shutdown procedure. */
638
639 spin_lock(&dlm->spinlock);
640 /* Clear ourselves from the domain map */
641 clear_bit(dlm->node_num, dlm->domain_map);
642 while ((node = find_next_bit(dlm->domain_map, O2NM_MAX_NODES,
643 0)) < O2NM_MAX_NODES) {
644 /* Drop the dlm spinlock. This is safe wrt the domain_map.
645 * -nodes cannot be added now as the
646 * query_join_handlers knows to respond with OK_NO_MAP
647 * -we catch the right network errors if a node is
648 * removed from the map while we're sending him the
649 * exit message. */
650 spin_unlock(&dlm->spinlock);
651
652 clear_node = 1;
653
654 status = dlm_send_one_domain_exit(dlm, DLM_EXIT_DOMAIN_MSG,
655 node);
656 if (status < 0 &&
657 status != -ENOPROTOOPT &&
658 status != -ENOTCONN) {
659 mlog(ML_NOTICE, "Error %d sending domain exit message "
660 "to node %d\n", status, node);
661
662 /* Not sure what to do here but lets sleep for
663 * a bit in case this was a transient
664 * error... */
665 msleep(DLM_DOMAIN_BACKOFF_MS);
666 clear_node = 0;
667 }
668
669 spin_lock(&dlm->spinlock);
670 /* If we're not clearing the node bit then we intend
671 * to loop back around to try again. */
672 if (clear_node)
673 clear_bit(node, dlm->domain_map);
674 }
675 spin_unlock(&dlm->spinlock);
676 }
677
678 int dlm_shutting_down(struct dlm_ctxt *dlm)
679 {
680 int ret = 0;
681
682 spin_lock(&dlm_domain_lock);
683
684 if (dlm->dlm_state == DLM_CTXT_IN_SHUTDOWN)
685 ret = 1;
686
687 spin_unlock(&dlm_domain_lock);
688
689 return ret;
690 }
691
692 void dlm_unregister_domain(struct dlm_ctxt *dlm)
693 {
694 int leave = 0;
695 struct dlm_lock_resource *res;
696
697 spin_lock(&dlm_domain_lock);
698 BUG_ON(dlm->dlm_state != DLM_CTXT_JOINED);
699 BUG_ON(!dlm->num_joins);
700
701 dlm->num_joins--;
702 if (!dlm->num_joins) {
703 /* We mark it "in shutdown" now so new register
704 * requests wait until we've completely left the
705 * domain. Don't use DLM_CTXT_LEAVING yet as we still
706 * want new domain joins to communicate with us at
707 * least until we've completed migration of our
708 * resources. */
709 dlm->dlm_state = DLM_CTXT_IN_SHUTDOWN;
710 leave = 1;
711 }
712 spin_unlock(&dlm_domain_lock);
713
714 if (leave) {
715 mlog(0, "shutting down domain %s\n", dlm->name);
716 dlm_begin_exit_domain(dlm);
717
718 /* We changed dlm state, notify the thread */
719 dlm_kick_thread(dlm, NULL);
720
721 while (dlm_migrate_all_locks(dlm)) {
722 /* Give dlm_thread time to purge the lockres' */
723 msleep(500);
724 mlog(0, "%s: more migration to do\n", dlm->name);
725 }
726
727 /* This list should be empty. If not, print remaining lockres */
728 if (!list_empty(&dlm->tracking_list)) {
729 mlog(ML_ERROR, "Following lockres' are still on the "
730 "tracking list:\n");
731 list_for_each_entry(res, &dlm->tracking_list, tracking)
732 dlm_print_one_lock_resource(res);
733 }
734
735 dlm_mark_domain_leaving(dlm);
736 dlm_leave_domain(dlm);
737 printk(KERN_NOTICE "o2dlm: Leaving domain %s\n", dlm->name);
738 dlm_force_free_mles(dlm);
739 dlm_complete_dlm_shutdown(dlm);
740 }
741 dlm_put(dlm);
742 }
743 EXPORT_SYMBOL_GPL(dlm_unregister_domain);
744
745 static int dlm_query_join_proto_check(char *proto_type, int node,
746 struct dlm_protocol_version *ours,
747 struct dlm_protocol_version *request)
748 {
749 int rc;
750 struct dlm_protocol_version proto = *request;
751
752 if (!dlm_protocol_compare(ours, &proto)) {
753 mlog(0,
754 "node %u wanted to join with %s locking protocol "
755 "%u.%u, we respond with %u.%u\n",
756 node, proto_type,
757 request->pv_major,
758 request->pv_minor,
759 proto.pv_major, proto.pv_minor);
760 request->pv_minor = proto.pv_minor;
761 rc = 0;
762 } else {
763 mlog(ML_NOTICE,
764 "Node %u wanted to join with %s locking "
765 "protocol %u.%u, but we have %u.%u, disallowing\n",
766 node, proto_type,
767 request->pv_major,
768 request->pv_minor,
769 ours->pv_major,
770 ours->pv_minor);
771 rc = 1;
772 }
773
774 return rc;
775 }
776
777 /*
778 * struct dlm_query_join_packet is made up of four one-byte fields. They
779 * are effectively in big-endian order already. However, little-endian
780 * machines swap them before putting the packet on the wire (because
781 * query_join's response is a status, and that status is treated as a u32
782 * on the wire). Thus, a big-endian and little-endian machines will treat
783 * this structure differently.
784 *
785 * The solution is to have little-endian machines swap the structure when
786 * converting from the structure to the u32 representation. This will
787 * result in the structure having the correct format on the wire no matter
788 * the host endian format.
789 */
790 static void dlm_query_join_packet_to_wire(struct dlm_query_join_packet *packet,
791 u32 *wire)
792 {
793 union dlm_query_join_response response;
794
795 response.packet = *packet;
796 *wire = be32_to_cpu(response.intval);
797 }
798
799 static void dlm_query_join_wire_to_packet(u32 wire,
800 struct dlm_query_join_packet *packet)
801 {
802 union dlm_query_join_response response;
803
804 response.intval = cpu_to_be32(wire);
805 *packet = response.packet;
806 }
807
808 static int dlm_query_join_handler(struct o2net_msg *msg, u32 len, void *data,
809 void **ret_data)
810 {
811 struct dlm_query_join_request *query;
812 struct dlm_query_join_packet packet = {
813 .code = JOIN_DISALLOW,
814 };
815 struct dlm_ctxt *dlm = NULL;
816 u32 response;
817 u8 nodenum;
818
819 query = (struct dlm_query_join_request *) msg->buf;
820
821 mlog(0, "node %u wants to join domain %s\n", query->node_idx,
822 query->domain);
823
824 /*
825 * If heartbeat doesn't consider the node live, tell it
826 * to back off and try again. This gives heartbeat a chance
827 * to catch up.
828 */
829 if (!o2hb_check_node_heartbeating_no_sem(query->node_idx)) {
830 mlog(0, "node %u is not in our live map yet\n",
831 query->node_idx);
832
833 packet.code = JOIN_DISALLOW;
834 goto respond;
835 }
836
837 packet.code = JOIN_OK_NO_MAP;
838
839 spin_lock(&dlm_domain_lock);
840 dlm = __dlm_lookup_domain_full(query->domain, query->name_len);
841 if (!dlm)
842 goto unlock_respond;
843
844 /*
845 * There is a small window where the joining node may not see the
846 * node(s) that just left but still part of the cluster. DISALLOW
847 * join request if joining node has different node map.
848 */
849 nodenum=0;
850 while (nodenum < O2NM_MAX_NODES) {
851 if (test_bit(nodenum, dlm->domain_map)) {
852 if (!byte_test_bit(nodenum, query->node_map)) {
853 mlog(0, "disallow join as node %u does not "
854 "have node %u in its nodemap\n",
855 query->node_idx, nodenum);
856 packet.code = JOIN_DISALLOW;
857 goto unlock_respond;
858 }
859 }
860 nodenum++;
861 }
862
863 /* Once the dlm ctxt is marked as leaving then we don't want
864 * to be put in someone's domain map.
865 * Also, explicitly disallow joining at certain troublesome
866 * times (ie. during recovery). */
867 if (dlm->dlm_state != DLM_CTXT_LEAVING) {
868 int bit = query->node_idx;
869 spin_lock(&dlm->spinlock);
870
871 if (dlm->dlm_state == DLM_CTXT_NEW &&
872 dlm->joining_node == DLM_LOCK_RES_OWNER_UNKNOWN) {
873 /*If this is a brand new context and we
874 * haven't started our join process yet, then
875 * the other node won the race. */
876 packet.code = JOIN_OK_NO_MAP;
877 } else if (dlm->joining_node != DLM_LOCK_RES_OWNER_UNKNOWN) {
878 /* Disallow parallel joins. */
879 packet.code = JOIN_DISALLOW;
880 } else if (dlm->reco.state & DLM_RECO_STATE_ACTIVE) {
881 mlog(0, "node %u trying to join, but recovery "
882 "is ongoing.\n", bit);
883 packet.code = JOIN_DISALLOW;
884 } else if (test_bit(bit, dlm->recovery_map)) {
885 mlog(0, "node %u trying to join, but it "
886 "still needs recovery.\n", bit);
887 packet.code = JOIN_DISALLOW;
888 } else if (test_bit(bit, dlm->domain_map)) {
889 mlog(0, "node %u trying to join, but it "
890 "is still in the domain! needs recovery?\n",
891 bit);
892 packet.code = JOIN_DISALLOW;
893 } else {
894 /* Alright we're fully a part of this domain
895 * so we keep some state as to who's joining
896 * and indicate to him that needs to be fixed
897 * up. */
898
899 /* Make sure we speak compatible locking protocols. */
900 if (dlm_query_join_proto_check("DLM", bit,
901 &dlm->dlm_locking_proto,
902 &query->dlm_proto)) {
903 packet.code = JOIN_PROTOCOL_MISMATCH;
904 } else if (dlm_query_join_proto_check("fs", bit,
905 &dlm->fs_locking_proto,
906 &query->fs_proto)) {
907 packet.code = JOIN_PROTOCOL_MISMATCH;
908 } else {
909 packet.dlm_minor = query->dlm_proto.pv_minor;
910 packet.fs_minor = query->fs_proto.pv_minor;
911 packet.code = JOIN_OK;
912 __dlm_set_joining_node(dlm, query->node_idx);
913 }
914 }
915
916 spin_unlock(&dlm->spinlock);
917 }
918 unlock_respond:
919 spin_unlock(&dlm_domain_lock);
920
921 respond:
922 mlog(0, "We respond with %u\n", packet.code);
923
924 dlm_query_join_packet_to_wire(&packet, &response);
925 return response;
926 }
927
928 static int dlm_assert_joined_handler(struct o2net_msg *msg, u32 len, void *data,
929 void **ret_data)
930 {
931 struct dlm_assert_joined *assert;
932 struct dlm_ctxt *dlm = NULL;
933
934 assert = (struct dlm_assert_joined *) msg->buf;
935
936 mlog(0, "node %u asserts join on domain %s\n", assert->node_idx,
937 assert->domain);
938
939 spin_lock(&dlm_domain_lock);
940 dlm = __dlm_lookup_domain_full(assert->domain, assert->name_len);
941 /* XXX should we consider no dlm ctxt an error? */
942 if (dlm) {
943 spin_lock(&dlm->spinlock);
944
945 /* Alright, this node has officially joined our
946 * domain. Set him in the map and clean up our
947 * leftover join state. */
948 BUG_ON(dlm->joining_node != assert->node_idx);
949
950 if (dlm->reco.state & DLM_RECO_STATE_ACTIVE) {
951 mlog(0, "dlm recovery is ongoing, disallow join\n");
952 spin_unlock(&dlm->spinlock);
953 spin_unlock(&dlm_domain_lock);
954 return -EAGAIN;
955 }
956
957 set_bit(assert->node_idx, dlm->domain_map);
958 clear_bit(assert->node_idx, dlm->exit_domain_map);
959 __dlm_set_joining_node(dlm, DLM_LOCK_RES_OWNER_UNKNOWN);
960
961 printk(KERN_NOTICE "o2dlm: Node %u joins domain %s ",
962 assert->node_idx, dlm->name);
963 __dlm_print_nodes(dlm);
964
965 /* notify anything attached to the heartbeat events */
966 dlm_hb_event_notify_attached(dlm, assert->node_idx, 1);
967
968 spin_unlock(&dlm->spinlock);
969 }
970 spin_unlock(&dlm_domain_lock);
971
972 return 0;
973 }
974
975 static int dlm_match_regions(struct dlm_ctxt *dlm,
976 struct dlm_query_region *qr,
977 char *local, int locallen)
978 {
979 char *remote = qr->qr_regions;
980 char *l, *r;
981 int localnr, i, j, foundit;
982 int status = 0;
983
984 if (!o2hb_global_heartbeat_active()) {
985 if (qr->qr_numregions) {
986 mlog(ML_ERROR, "Domain %s: Joining node %d has global "
987 "heartbeat enabled but local node %d does not\n",
988 qr->qr_domain, qr->qr_node, dlm->node_num);
989 status = -EINVAL;
990 }
991 goto bail;
992 }
993
994 if (o2hb_global_heartbeat_active() && !qr->qr_numregions) {
995 mlog(ML_ERROR, "Domain %s: Local node %d has global "
996 "heartbeat enabled but joining node %d does not\n",
997 qr->qr_domain, dlm->node_num, qr->qr_node);
998 status = -EINVAL;
999 goto bail;
1000 }
1001
1002 r = remote;
1003 for (i = 0; i < qr->qr_numregions; ++i) {
1004 mlog(0, "Region %.*s\n", O2HB_MAX_REGION_NAME_LEN, r);
1005 r += O2HB_MAX_REGION_NAME_LEN;
1006 }
1007
1008 localnr = min(O2NM_MAX_REGIONS, locallen/O2HB_MAX_REGION_NAME_LEN);
1009 localnr = o2hb_get_all_regions(local, (u8)localnr);
1010
1011 /* compare local regions with remote */
1012 l = local;
1013 for (i = 0; i < localnr; ++i) {
1014 foundit = 0;
1015 r = remote;
1016 for (j = 0; j <= qr->qr_numregions; ++j) {
1017 if (!memcmp(l, r, O2HB_MAX_REGION_NAME_LEN)) {
1018 foundit = 1;
1019 break;
1020 }
1021 r += O2HB_MAX_REGION_NAME_LEN;
1022 }
1023 if (!foundit) {
1024 status = -EINVAL;
1025 mlog(ML_ERROR, "Domain %s: Region '%.*s' registered "
1026 "in local node %d but not in joining node %d\n",
1027 qr->qr_domain, O2HB_MAX_REGION_NAME_LEN, l,
1028 dlm->node_num, qr->qr_node);
1029 goto bail;
1030 }
1031 l += O2HB_MAX_REGION_NAME_LEN;
1032 }
1033
1034 /* compare remote with local regions */
1035 r = remote;
1036 for (i = 0; i < qr->qr_numregions; ++i) {
1037 foundit = 0;
1038 l = local;
1039 for (j = 0; j < localnr; ++j) {
1040 if (!memcmp(r, l, O2HB_MAX_REGION_NAME_LEN)) {
1041 foundit = 1;
1042 break;
1043 }
1044 l += O2HB_MAX_REGION_NAME_LEN;
1045 }
1046 if (!foundit) {
1047 status = -EINVAL;
1048 mlog(ML_ERROR, "Domain %s: Region '%.*s' registered "
1049 "in joining node %d but not in local node %d\n",
1050 qr->qr_domain, O2HB_MAX_REGION_NAME_LEN, r,
1051 qr->qr_node, dlm->node_num);
1052 goto bail;
1053 }
1054 r += O2HB_MAX_REGION_NAME_LEN;
1055 }
1056
1057 bail:
1058 return status;
1059 }
1060
1061 static int dlm_send_regions(struct dlm_ctxt *dlm, unsigned long *node_map)
1062 {
1063 struct dlm_query_region *qr = NULL;
1064 int status, ret = 0, i;
1065 char *p;
1066
1067 if (find_next_bit(node_map, O2NM_MAX_NODES, 0) >= O2NM_MAX_NODES)
1068 goto bail;
1069
1070 qr = kzalloc(sizeof(struct dlm_query_region), GFP_KERNEL);
1071 if (!qr) {
1072 ret = -ENOMEM;
1073 mlog_errno(ret);
1074 goto bail;
1075 }
1076
1077 qr->qr_node = dlm->node_num;
1078 qr->qr_namelen = strlen(dlm->name);
1079 memcpy(qr->qr_domain, dlm->name, qr->qr_namelen);
1080 /* if local hb, the numregions will be zero */
1081 if (o2hb_global_heartbeat_active())
1082 qr->qr_numregions = o2hb_get_all_regions(qr->qr_regions,
1083 O2NM_MAX_REGIONS);
1084
1085 p = qr->qr_regions;
1086 for (i = 0; i < qr->qr_numregions; ++i, p += O2HB_MAX_REGION_NAME_LEN)
1087 mlog(0, "Region %.*s\n", O2HB_MAX_REGION_NAME_LEN, p);
1088
1089 i = -1;
1090 while ((i = find_next_bit(node_map, O2NM_MAX_NODES,
1091 i + 1)) < O2NM_MAX_NODES) {
1092 if (i == dlm->node_num)
1093 continue;
1094
1095 mlog(0, "Sending regions to node %d\n", i);
1096
1097 ret = o2net_send_message(DLM_QUERY_REGION, DLM_MOD_KEY, qr,
1098 sizeof(struct dlm_query_region),
1099 i, &status);
1100 if (ret >= 0)
1101 ret = status;
1102 if (ret) {
1103 mlog(ML_ERROR, "Region mismatch %d, node %d\n",
1104 ret, i);
1105 break;
1106 }
1107 }
1108
1109 bail:
1110 kfree(qr);
1111 return ret;
1112 }
1113
1114 static int dlm_query_region_handler(struct o2net_msg *msg, u32 len,
1115 void *data, void **ret_data)
1116 {
1117 struct dlm_query_region *qr;
1118 struct dlm_ctxt *dlm = NULL;
1119 char *local = NULL;
1120 int status = 0;
1121
1122 qr = (struct dlm_query_region *) msg->buf;
1123
1124 mlog(0, "Node %u queries hb regions on domain %s\n", qr->qr_node,
1125 qr->qr_domain);
1126
1127 /* buffer used in dlm_mast_regions() */
1128 local = kmalloc(sizeof(qr->qr_regions), GFP_KERNEL);
1129 if (!local)
1130 return -ENOMEM;
1131
1132 status = -EINVAL;
1133
1134 spin_lock(&dlm_domain_lock);
1135 dlm = __dlm_lookup_domain_full(qr->qr_domain, qr->qr_namelen);
1136 if (!dlm) {
1137 mlog(ML_ERROR, "Node %d queried hb regions on domain %s "
1138 "before join domain\n", qr->qr_node, qr->qr_domain);
1139 goto out_domain_lock;
1140 }
1141
1142 spin_lock(&dlm->spinlock);
1143 if (dlm->joining_node != qr->qr_node) {
1144 mlog(ML_ERROR, "Node %d queried hb regions on domain %s "
1145 "but joining node is %d\n", qr->qr_node, qr->qr_domain,
1146 dlm->joining_node);
1147 goto out_dlm_lock;
1148 }
1149
1150 /* Support for global heartbeat was added in 1.1 */
1151 if (dlm->dlm_locking_proto.pv_major == 1 &&
1152 dlm->dlm_locking_proto.pv_minor == 0) {
1153 mlog(ML_ERROR, "Node %d queried hb regions on domain %s "
1154 "but active dlm protocol is %d.%d\n", qr->qr_node,
1155 qr->qr_domain, dlm->dlm_locking_proto.pv_major,
1156 dlm->dlm_locking_proto.pv_minor);
1157 goto out_dlm_lock;
1158 }
1159
1160 status = dlm_match_regions(dlm, qr, local, sizeof(qr->qr_regions));
1161
1162 out_dlm_lock:
1163 spin_unlock(&dlm->spinlock);
1164
1165 out_domain_lock:
1166 spin_unlock(&dlm_domain_lock);
1167
1168 kfree(local);
1169
1170 return status;
1171 }
1172
1173 static int dlm_match_nodes(struct dlm_ctxt *dlm, struct dlm_query_nodeinfo *qn)
1174 {
1175 struct o2nm_node *local;
1176 struct dlm_node_info *remote;
1177 int i, j;
1178 int status = 0;
1179
1180 for (j = 0; j < qn->qn_numnodes; ++j)
1181 mlog(0, "Node %3d, %pI4:%u\n", qn->qn_nodes[j].ni_nodenum,
1182 &(qn->qn_nodes[j].ni_ipv4_address),
1183 ntohs(qn->qn_nodes[j].ni_ipv4_port));
1184
1185 for (i = 0; i < O2NM_MAX_NODES && !status; ++i) {
1186 local = o2nm_get_node_by_num(i);
1187 remote = NULL;
1188 for (j = 0; j < qn->qn_numnodes; ++j) {
1189 if (qn->qn_nodes[j].ni_nodenum == i) {
1190 remote = &(qn->qn_nodes[j]);
1191 break;
1192 }
1193 }
1194
1195 if (!local && !remote)
1196 continue;
1197
1198 if ((local && !remote) || (!local && remote))
1199 status = -EINVAL;
1200
1201 if (!status &&
1202 ((remote->ni_nodenum != local->nd_num) ||
1203 (remote->ni_ipv4_port != local->nd_ipv4_port) ||
1204 (remote->ni_ipv4_address != local->nd_ipv4_address)))
1205 status = -EINVAL;
1206
1207 if (status) {
1208 if (remote && !local)
1209 mlog(ML_ERROR, "Domain %s: Node %d (%pI4:%u) "
1210 "registered in joining node %d but not in "
1211 "local node %d\n", qn->qn_domain,
1212 remote->ni_nodenum,
1213 &(remote->ni_ipv4_address),
1214 ntohs(remote->ni_ipv4_port),
1215 qn->qn_nodenum, dlm->node_num);
1216 if (local && !remote)
1217 mlog(ML_ERROR, "Domain %s: Node %d (%pI4:%u) "
1218 "registered in local node %d but not in "
1219 "joining node %d\n", qn->qn_domain,
1220 local->nd_num, &(local->nd_ipv4_address),
1221 ntohs(local->nd_ipv4_port),
1222 dlm->node_num, qn->qn_nodenum);
1223 BUG_ON((!local && !remote));
1224 }
1225
1226 if (local)
1227 o2nm_node_put(local);
1228 }
1229
1230 return status;
1231 }
1232
1233 static int dlm_send_nodeinfo(struct dlm_ctxt *dlm, unsigned long *node_map)
1234 {
1235 struct dlm_query_nodeinfo *qn = NULL;
1236 struct o2nm_node *node;
1237 int ret = 0, status, count, i;
1238
1239 if (find_next_bit(node_map, O2NM_MAX_NODES, 0) >= O2NM_MAX_NODES)
1240 goto bail;
1241
1242 qn = kzalloc(sizeof(struct dlm_query_nodeinfo), GFP_KERNEL);
1243 if (!qn) {
1244 ret = -ENOMEM;
1245 mlog_errno(ret);
1246 goto bail;
1247 }
1248
1249 for (i = 0, count = 0; i < O2NM_MAX_NODES; ++i) {
1250 node = o2nm_get_node_by_num(i);
1251 if (!node)
1252 continue;
1253 qn->qn_nodes[count].ni_nodenum = node->nd_num;
1254 qn->qn_nodes[count].ni_ipv4_port = node->nd_ipv4_port;
1255 qn->qn_nodes[count].ni_ipv4_address = node->nd_ipv4_address;
1256 mlog(0, "Node %3d, %pI4:%u\n", node->nd_num,
1257 &(node->nd_ipv4_address), ntohs(node->nd_ipv4_port));
1258 ++count;
1259 o2nm_node_put(node);
1260 }
1261
1262 qn->qn_nodenum = dlm->node_num;
1263 qn->qn_numnodes = count;
1264 qn->qn_namelen = strlen(dlm->name);
1265 memcpy(qn->qn_domain, dlm->name, qn->qn_namelen);
1266
1267 i = -1;
1268 while ((i = find_next_bit(node_map, O2NM_MAX_NODES,
1269 i + 1)) < O2NM_MAX_NODES) {
1270 if (i == dlm->node_num)
1271 continue;
1272
1273 mlog(0, "Sending nodeinfo to node %d\n", i);
1274
1275 ret = o2net_send_message(DLM_QUERY_NODEINFO, DLM_MOD_KEY,
1276 qn, sizeof(struct dlm_query_nodeinfo),
1277 i, &status);
1278 if (ret >= 0)
1279 ret = status;
1280 if (ret) {
1281 mlog(ML_ERROR, "node mismatch %d, node %d\n", ret, i);
1282 break;
1283 }
1284 }
1285
1286 bail:
1287 kfree(qn);
1288 return ret;
1289 }
1290
1291 static int dlm_query_nodeinfo_handler(struct o2net_msg *msg, u32 len,
1292 void *data, void **ret_data)
1293 {
1294 struct dlm_query_nodeinfo *qn;
1295 struct dlm_ctxt *dlm = NULL;
1296 int locked = 0, status = -EINVAL;
1297
1298 qn = (struct dlm_query_nodeinfo *) msg->buf;
1299
1300 mlog(0, "Node %u queries nodes on domain %s\n", qn->qn_nodenum,
1301 qn->qn_domain);
1302
1303 spin_lock(&dlm_domain_lock);
1304 dlm = __dlm_lookup_domain_full(qn->qn_domain, qn->qn_namelen);
1305 if (!dlm) {
1306 mlog(ML_ERROR, "Node %d queried nodes on domain %s before "
1307 "join domain\n", qn->qn_nodenum, qn->qn_domain);
1308 goto bail;
1309 }
1310
1311 spin_lock(&dlm->spinlock);
1312 locked = 1;
1313 if (dlm->joining_node != qn->qn_nodenum) {
1314 mlog(ML_ERROR, "Node %d queried nodes on domain %s but "
1315 "joining node is %d\n", qn->qn_nodenum, qn->qn_domain,
1316 dlm->joining_node);
1317 goto bail;
1318 }
1319
1320 /* Support for node query was added in 1.1 */
1321 if (dlm->dlm_locking_proto.pv_major == 1 &&
1322 dlm->dlm_locking_proto.pv_minor == 0) {
1323 mlog(ML_ERROR, "Node %d queried nodes on domain %s "
1324 "but active dlm protocol is %d.%d\n", qn->qn_nodenum,
1325 qn->qn_domain, dlm->dlm_locking_proto.pv_major,
1326 dlm->dlm_locking_proto.pv_minor);
1327 goto bail;
1328 }
1329
1330 status = dlm_match_nodes(dlm, qn);
1331
1332 bail:
1333 if (locked)
1334 spin_unlock(&dlm->spinlock);
1335 spin_unlock(&dlm_domain_lock);
1336
1337 return status;
1338 }
1339
1340 static int dlm_cancel_join_handler(struct o2net_msg *msg, u32 len, void *data,
1341 void **ret_data)
1342 {
1343 struct dlm_cancel_join *cancel;
1344 struct dlm_ctxt *dlm = NULL;
1345
1346 cancel = (struct dlm_cancel_join *) msg->buf;
1347
1348 mlog(0, "node %u cancels join on domain %s\n", cancel->node_idx,
1349 cancel->domain);
1350
1351 spin_lock(&dlm_domain_lock);
1352 dlm = __dlm_lookup_domain_full(cancel->domain, cancel->name_len);
1353
1354 if (dlm) {
1355 spin_lock(&dlm->spinlock);
1356
1357 /* Yikes, this guy wants to cancel his join. No
1358 * problem, we simply cleanup our join state. */
1359 BUG_ON(dlm->joining_node != cancel->node_idx);
1360 __dlm_set_joining_node(dlm, DLM_LOCK_RES_OWNER_UNKNOWN);
1361
1362 spin_unlock(&dlm->spinlock);
1363 }
1364 spin_unlock(&dlm_domain_lock);
1365
1366 return 0;
1367 }
1368
1369 static int dlm_send_one_join_cancel(struct dlm_ctxt *dlm,
1370 unsigned int node)
1371 {
1372 int status;
1373 struct dlm_cancel_join cancel_msg;
1374
1375 memset(&cancel_msg, 0, sizeof(cancel_msg));
1376 cancel_msg.node_idx = dlm->node_num;
1377 cancel_msg.name_len = strlen(dlm->name);
1378 memcpy(cancel_msg.domain, dlm->name, cancel_msg.name_len);
1379
1380 status = o2net_send_message(DLM_CANCEL_JOIN_MSG, DLM_MOD_KEY,
1381 &cancel_msg, sizeof(cancel_msg), node,
1382 NULL);
1383 if (status < 0) {
1384 mlog(ML_ERROR, "Error %d when sending message %u (key 0x%x) to "
1385 "node %u\n", status, DLM_CANCEL_JOIN_MSG, DLM_MOD_KEY,
1386 node);
1387 goto bail;
1388 }
1389
1390 bail:
1391 return status;
1392 }
1393
1394 /* map_size should be in bytes. */
1395 static int dlm_send_join_cancels(struct dlm_ctxt *dlm,
1396 unsigned long *node_map,
1397 unsigned int map_size)
1398 {
1399 int status, tmpstat;
1400 int node;
1401
1402 if (map_size != (BITS_TO_LONGS(O2NM_MAX_NODES) *
1403 sizeof(unsigned long))) {
1404 mlog(ML_ERROR,
1405 "map_size %u != BITS_TO_LONGS(O2NM_MAX_NODES) %u\n",
1406 map_size, (unsigned)BITS_TO_LONGS(O2NM_MAX_NODES));
1407 return -EINVAL;
1408 }
1409
1410 status = 0;
1411 node = -1;
1412 while ((node = find_next_bit(node_map, O2NM_MAX_NODES,
1413 node + 1)) < O2NM_MAX_NODES) {
1414 if (node == dlm->node_num)
1415 continue;
1416
1417 tmpstat = dlm_send_one_join_cancel(dlm, node);
1418 if (tmpstat) {
1419 mlog(ML_ERROR, "Error return %d cancelling join on "
1420 "node %d\n", tmpstat, node);
1421 if (!status)
1422 status = tmpstat;
1423 }
1424 }
1425
1426 if (status)
1427 mlog_errno(status);
1428 return status;
1429 }
1430
1431 static int dlm_request_join(struct dlm_ctxt *dlm,
1432 int node,
1433 enum dlm_query_join_response_code *response)
1434 {
1435 int status;
1436 struct dlm_query_join_request join_msg;
1437 struct dlm_query_join_packet packet;
1438 u32 join_resp;
1439
1440 mlog(0, "querying node %d\n", node);
1441
1442 memset(&join_msg, 0, sizeof(join_msg));
1443 join_msg.node_idx = dlm->node_num;
1444 join_msg.name_len = strlen(dlm->name);
1445 memcpy(join_msg.domain, dlm->name, join_msg.name_len);
1446 join_msg.dlm_proto = dlm->dlm_locking_proto;
1447 join_msg.fs_proto = dlm->fs_locking_proto;
1448
1449 /* copy live node map to join message */
1450 byte_copymap(join_msg.node_map, dlm->live_nodes_map, O2NM_MAX_NODES);
1451
1452 status = o2net_send_message(DLM_QUERY_JOIN_MSG, DLM_MOD_KEY, &join_msg,
1453 sizeof(join_msg), node, &join_resp);
1454 if (status < 0 && status != -ENOPROTOOPT) {
1455 mlog(ML_ERROR, "Error %d when sending message %u (key 0x%x) to "
1456 "node %u\n", status, DLM_QUERY_JOIN_MSG, DLM_MOD_KEY,
1457 node);
1458 goto bail;
1459 }
1460 dlm_query_join_wire_to_packet(join_resp, &packet);
1461
1462 /* -ENOPROTOOPT from the net code means the other side isn't
1463 listening for our message type -- that's fine, it means
1464 his dlm isn't up, so we can consider him a 'yes' but not
1465 joined into the domain. */
1466 if (status == -ENOPROTOOPT) {
1467 status = 0;
1468 *response = JOIN_OK_NO_MAP;
1469 } else {
1470 *response = packet.code;
1471 switch (packet.code) {
1472 case JOIN_DISALLOW:
1473 case JOIN_OK_NO_MAP:
1474 break;
1475 case JOIN_PROTOCOL_MISMATCH:
1476 mlog(ML_NOTICE,
1477 "This node requested DLM locking protocol %u.%u and "
1478 "filesystem locking protocol %u.%u. At least one of "
1479 "the protocol versions on node %d is not compatible, "
1480 "disconnecting\n",
1481 dlm->dlm_locking_proto.pv_major,
1482 dlm->dlm_locking_proto.pv_minor,
1483 dlm->fs_locking_proto.pv_major,
1484 dlm->fs_locking_proto.pv_minor,
1485 node);
1486 status = -EPROTO;
1487 break;
1488 case JOIN_OK:
1489 /* Use the same locking protocol as the remote node */
1490 dlm->dlm_locking_proto.pv_minor = packet.dlm_minor;
1491 dlm->fs_locking_proto.pv_minor = packet.fs_minor;
1492 mlog(0,
1493 "Node %d responds JOIN_OK with DLM locking protocol "
1494 "%u.%u and fs locking protocol %u.%u\n",
1495 node,
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 break;
1501 default:
1502 status = -EINVAL;
1503 mlog(ML_ERROR, "invalid response %d from node %u\n",
1504 packet.code, node);
1505 /* Reset response to JOIN_DISALLOW */
1506 *response = JOIN_DISALLOW;
1507 break;
1508 }
1509 }
1510
1511 mlog(0, "status %d, node %d response is %d\n", status, node,
1512 *response);
1513
1514 bail:
1515 return status;
1516 }
1517
1518 static int dlm_send_one_join_assert(struct dlm_ctxt *dlm,
1519 unsigned int node)
1520 {
1521 int status;
1522 int ret;
1523 struct dlm_assert_joined assert_msg;
1524
1525 mlog(0, "Sending join assert to node %u\n", node);
1526
1527 memset(&assert_msg, 0, sizeof(assert_msg));
1528 assert_msg.node_idx = dlm->node_num;
1529 assert_msg.name_len = strlen(dlm->name);
1530 memcpy(assert_msg.domain, dlm->name, assert_msg.name_len);
1531
1532 status = o2net_send_message(DLM_ASSERT_JOINED_MSG, DLM_MOD_KEY,
1533 &assert_msg, sizeof(assert_msg), node,
1534 &ret);
1535 if (status < 0)
1536 mlog(ML_ERROR, "Error %d when sending message %u (key 0x%x) to "
1537 "node %u\n", status, DLM_ASSERT_JOINED_MSG, DLM_MOD_KEY,
1538 node);
1539 else
1540 status = ret;
1541
1542 return status;
1543 }
1544
1545 static void dlm_send_join_asserts(struct dlm_ctxt *dlm,
1546 unsigned long *node_map)
1547 {
1548 int status, node, live;
1549
1550 status = 0;
1551 node = -1;
1552 while ((node = find_next_bit(node_map, O2NM_MAX_NODES,
1553 node + 1)) < O2NM_MAX_NODES) {
1554 if (node == dlm->node_num)
1555 continue;
1556
1557 do {
1558 /* It is very important that this message be
1559 * received so we spin until either the node
1560 * has died or it gets the message. */
1561 status = dlm_send_one_join_assert(dlm, node);
1562
1563 spin_lock(&dlm->spinlock);
1564 live = test_bit(node, dlm->live_nodes_map);
1565 spin_unlock(&dlm->spinlock);
1566
1567 if (status) {
1568 mlog(ML_ERROR, "Error return %d asserting "
1569 "join on node %d\n", status, node);
1570
1571 /* give us some time between errors... */
1572 if (live)
1573 msleep(DLM_DOMAIN_BACKOFF_MS);
1574 }
1575 } while (status && live);
1576 }
1577 }
1578
1579 struct domain_join_ctxt {
1580 unsigned long live_map[BITS_TO_LONGS(O2NM_MAX_NODES)];
1581 unsigned long yes_resp_map[BITS_TO_LONGS(O2NM_MAX_NODES)];
1582 };
1583
1584 static int dlm_should_restart_join(struct dlm_ctxt *dlm,
1585 struct domain_join_ctxt *ctxt,
1586 enum dlm_query_join_response_code response)
1587 {
1588 int ret;
1589
1590 if (response == JOIN_DISALLOW) {
1591 mlog(0, "Latest response of disallow -- should restart\n");
1592 return 1;
1593 }
1594
1595 spin_lock(&dlm->spinlock);
1596 /* For now, we restart the process if the node maps have
1597 * changed at all */
1598 ret = memcmp(ctxt->live_map, dlm->live_nodes_map,
1599 sizeof(dlm->live_nodes_map));
1600 spin_unlock(&dlm->spinlock);
1601
1602 if (ret)
1603 mlog(0, "Node maps changed -- should restart\n");
1604
1605 return ret;
1606 }
1607
1608 static int dlm_try_to_join_domain(struct dlm_ctxt *dlm)
1609 {
1610 int status = 0, tmpstat, node;
1611 struct domain_join_ctxt *ctxt;
1612 enum dlm_query_join_response_code response = JOIN_DISALLOW;
1613
1614 mlog(0, "%p", dlm);
1615
1616 ctxt = kzalloc(sizeof(*ctxt), GFP_KERNEL);
1617 if (!ctxt) {
1618 status = -ENOMEM;
1619 mlog_errno(status);
1620 goto bail;
1621 }
1622
1623 /* group sem locking should work for us here -- we're already
1624 * registered for heartbeat events so filling this should be
1625 * atomic wrt getting those handlers called. */
1626 o2hb_fill_node_map(dlm->live_nodes_map, sizeof(dlm->live_nodes_map));
1627
1628 spin_lock(&dlm->spinlock);
1629 memcpy(ctxt->live_map, dlm->live_nodes_map, sizeof(ctxt->live_map));
1630
1631 __dlm_set_joining_node(dlm, dlm->node_num);
1632
1633 spin_unlock(&dlm->spinlock);
1634
1635 node = -1;
1636 while ((node = find_next_bit(ctxt->live_map, O2NM_MAX_NODES,
1637 node + 1)) < O2NM_MAX_NODES) {
1638 if (node == dlm->node_num)
1639 continue;
1640
1641 status = dlm_request_join(dlm, node, &response);
1642 if (status < 0) {
1643 mlog_errno(status);
1644 goto bail;
1645 }
1646
1647 /* Ok, either we got a response or the node doesn't have a
1648 * dlm up. */
1649 if (response == JOIN_OK)
1650 set_bit(node, ctxt->yes_resp_map);
1651
1652 if (dlm_should_restart_join(dlm, ctxt, response)) {
1653 status = -EAGAIN;
1654 goto bail;
1655 }
1656 }
1657
1658 mlog(0, "Yay, done querying nodes!\n");
1659
1660 /* Yay, everyone agree's we can join the domain. My domain is
1661 * comprised of all nodes who were put in the
1662 * yes_resp_map. Copy that into our domain map and send a join
1663 * assert message to clean up everyone elses state. */
1664 spin_lock(&dlm->spinlock);
1665 memcpy(dlm->domain_map, ctxt->yes_resp_map,
1666 sizeof(ctxt->yes_resp_map));
1667 set_bit(dlm->node_num, dlm->domain_map);
1668 spin_unlock(&dlm->spinlock);
1669
1670 /* Support for global heartbeat and node info was added in 1.1 */
1671 if (dlm->dlm_locking_proto.pv_major > 1 ||
1672 dlm->dlm_locking_proto.pv_minor > 0) {
1673 status = dlm_send_nodeinfo(dlm, ctxt->yes_resp_map);
1674 if (status) {
1675 mlog_errno(status);
1676 goto bail;
1677 }
1678 status = dlm_send_regions(dlm, ctxt->yes_resp_map);
1679 if (status) {
1680 mlog_errno(status);
1681 goto bail;
1682 }
1683 }
1684
1685 dlm_send_join_asserts(dlm, ctxt->yes_resp_map);
1686
1687 /* Joined state *must* be set before the joining node
1688 * information, otherwise the query_join handler may read no
1689 * current joiner but a state of NEW and tell joining nodes
1690 * we're not in the domain. */
1691 spin_lock(&dlm_domain_lock);
1692 dlm->dlm_state = DLM_CTXT_JOINED;
1693 dlm->num_joins++;
1694 spin_unlock(&dlm_domain_lock);
1695
1696 bail:
1697 spin_lock(&dlm->spinlock);
1698 __dlm_set_joining_node(dlm, DLM_LOCK_RES_OWNER_UNKNOWN);
1699 if (!status) {
1700 printk(KERN_NOTICE "o2dlm: Joining domain %s ", dlm->name);
1701 __dlm_print_nodes(dlm);
1702 }
1703 spin_unlock(&dlm->spinlock);
1704
1705 if (ctxt) {
1706 /* Do we need to send a cancel message to any nodes? */
1707 if (status < 0) {
1708 tmpstat = dlm_send_join_cancels(dlm,
1709 ctxt->yes_resp_map,
1710 sizeof(ctxt->yes_resp_map));
1711 if (tmpstat < 0)
1712 mlog_errno(tmpstat);
1713 }
1714 kfree(ctxt);
1715 }
1716
1717 mlog(0, "returning %d\n", status);
1718 return status;
1719 }
1720
1721 static void dlm_unregister_domain_handlers(struct dlm_ctxt *dlm)
1722 {
1723 o2hb_unregister_callback(dlm->name, &dlm->dlm_hb_up);
1724 o2hb_unregister_callback(dlm->name, &dlm->dlm_hb_down);
1725 o2net_unregister_handler_list(&dlm->dlm_domain_handlers);
1726 }
1727
1728 static int dlm_register_domain_handlers(struct dlm_ctxt *dlm)
1729 {
1730 int status;
1731
1732 mlog(0, "registering handlers.\n");
1733
1734 o2hb_setup_callback(&dlm->dlm_hb_down, O2HB_NODE_DOWN_CB,
1735 dlm_hb_node_down_cb, dlm, DLM_HB_NODE_DOWN_PRI);
1736 o2hb_setup_callback(&dlm->dlm_hb_up, O2HB_NODE_UP_CB,
1737 dlm_hb_node_up_cb, dlm, DLM_HB_NODE_UP_PRI);
1738
1739 status = o2hb_register_callback(dlm->name, &dlm->dlm_hb_down);
1740 if (status)
1741 goto bail;
1742
1743 status = o2hb_register_callback(dlm->name, &dlm->dlm_hb_up);
1744 if (status)
1745 goto bail;
1746
1747 status = o2net_register_handler(DLM_MASTER_REQUEST_MSG, dlm->key,
1748 sizeof(struct dlm_master_request),
1749 dlm_master_request_handler,
1750 dlm, NULL, &dlm->dlm_domain_handlers);
1751 if (status)
1752 goto bail;
1753
1754 status = o2net_register_handler(DLM_ASSERT_MASTER_MSG, dlm->key,
1755 sizeof(struct dlm_assert_master),
1756 dlm_assert_master_handler,
1757 dlm, dlm_assert_master_post_handler,
1758 &dlm->dlm_domain_handlers);
1759 if (status)
1760 goto bail;
1761
1762 status = o2net_register_handler(DLM_CREATE_LOCK_MSG, dlm->key,
1763 sizeof(struct dlm_create_lock),
1764 dlm_create_lock_handler,
1765 dlm, NULL, &dlm->dlm_domain_handlers);
1766 if (status)
1767 goto bail;
1768
1769 status = o2net_register_handler(DLM_CONVERT_LOCK_MSG, dlm->key,
1770 DLM_CONVERT_LOCK_MAX_LEN,
1771 dlm_convert_lock_handler,
1772 dlm, NULL, &dlm->dlm_domain_handlers);
1773 if (status)
1774 goto bail;
1775
1776 status = o2net_register_handler(DLM_UNLOCK_LOCK_MSG, dlm->key,
1777 DLM_UNLOCK_LOCK_MAX_LEN,
1778 dlm_unlock_lock_handler,
1779 dlm, NULL, &dlm->dlm_domain_handlers);
1780 if (status)
1781 goto bail;
1782
1783 status = o2net_register_handler(DLM_PROXY_AST_MSG, dlm->key,
1784 DLM_PROXY_AST_MAX_LEN,
1785 dlm_proxy_ast_handler,
1786 dlm, NULL, &dlm->dlm_domain_handlers);
1787 if (status)
1788 goto bail;
1789
1790 status = o2net_register_handler(DLM_EXIT_DOMAIN_MSG, dlm->key,
1791 sizeof(struct dlm_exit_domain),
1792 dlm_exit_domain_handler,
1793 dlm, NULL, &dlm->dlm_domain_handlers);
1794 if (status)
1795 goto bail;
1796
1797 status = o2net_register_handler(DLM_DEREF_LOCKRES_MSG, dlm->key,
1798 sizeof(struct dlm_deref_lockres),
1799 dlm_deref_lockres_handler,
1800 dlm, NULL, &dlm->dlm_domain_handlers);
1801 if (status)
1802 goto bail;
1803
1804 status = o2net_register_handler(DLM_MIGRATE_REQUEST_MSG, dlm->key,
1805 sizeof(struct dlm_migrate_request),
1806 dlm_migrate_request_handler,
1807 dlm, NULL, &dlm->dlm_domain_handlers);
1808 if (status)
1809 goto bail;
1810
1811 status = o2net_register_handler(DLM_MIG_LOCKRES_MSG, dlm->key,
1812 DLM_MIG_LOCKRES_MAX_LEN,
1813 dlm_mig_lockres_handler,
1814 dlm, NULL, &dlm->dlm_domain_handlers);
1815 if (status)
1816 goto bail;
1817
1818 status = o2net_register_handler(DLM_MASTER_REQUERY_MSG, dlm->key,
1819 sizeof(struct dlm_master_requery),
1820 dlm_master_requery_handler,
1821 dlm, NULL, &dlm->dlm_domain_handlers);
1822 if (status)
1823 goto bail;
1824
1825 status = o2net_register_handler(DLM_LOCK_REQUEST_MSG, dlm->key,
1826 sizeof(struct dlm_lock_request),
1827 dlm_request_all_locks_handler,
1828 dlm, NULL, &dlm->dlm_domain_handlers);
1829 if (status)
1830 goto bail;
1831
1832 status = o2net_register_handler(DLM_RECO_DATA_DONE_MSG, dlm->key,
1833 sizeof(struct dlm_reco_data_done),
1834 dlm_reco_data_done_handler,
1835 dlm, NULL, &dlm->dlm_domain_handlers);
1836 if (status)
1837 goto bail;
1838
1839 status = o2net_register_handler(DLM_BEGIN_RECO_MSG, dlm->key,
1840 sizeof(struct dlm_begin_reco),
1841 dlm_begin_reco_handler,
1842 dlm, NULL, &dlm->dlm_domain_handlers);
1843 if (status)
1844 goto bail;
1845
1846 status = o2net_register_handler(DLM_FINALIZE_RECO_MSG, dlm->key,
1847 sizeof(struct dlm_finalize_reco),
1848 dlm_finalize_reco_handler,
1849 dlm, NULL, &dlm->dlm_domain_handlers);
1850 if (status)
1851 goto bail;
1852
1853 status = o2net_register_handler(DLM_BEGIN_EXIT_DOMAIN_MSG, dlm->key,
1854 sizeof(struct dlm_exit_domain),
1855 dlm_begin_exit_domain_handler,
1856 dlm, NULL, &dlm->dlm_domain_handlers);
1857 if (status)
1858 goto bail;
1859
1860 status = o2net_register_handler(DLM_DEREF_LOCKRES_DONE, dlm->key,
1861 sizeof(struct dlm_deref_lockres_done),
1862 dlm_deref_lockres_done_handler,
1863 dlm, NULL, &dlm->dlm_domain_handlers);
1864 bail:
1865 if (status)
1866 dlm_unregister_domain_handlers(dlm);
1867
1868 return status;
1869 }
1870
1871 static int dlm_join_domain(struct dlm_ctxt *dlm)
1872 {
1873 int status;
1874 unsigned int backoff;
1875 unsigned int total_backoff = 0;
1876 char wq_name[O2NM_MAX_NAME_LEN];
1877
1878 BUG_ON(!dlm);
1879
1880 mlog(0, "Join domain %s\n", dlm->name);
1881
1882 status = dlm_register_domain_handlers(dlm);
1883 if (status) {
1884 mlog_errno(status);
1885 goto bail;
1886 }
1887
1888 status = dlm_launch_thread(dlm);
1889 if (status < 0) {
1890 mlog_errno(status);
1891 goto bail;
1892 }
1893
1894 status = dlm_launch_recovery_thread(dlm);
1895 if (status < 0) {
1896 mlog_errno(status);
1897 goto bail;
1898 }
1899
1900 status = dlm_debug_init(dlm);
1901 if (status < 0) {
1902 mlog_errno(status);
1903 goto bail;
1904 }
1905
1906 snprintf(wq_name, O2NM_MAX_NAME_LEN, "dlm_wq-%s", dlm->name);
1907 dlm->dlm_worker = alloc_workqueue(wq_name, WQ_MEM_RECLAIM, 0);
1908 if (!dlm->dlm_worker) {
1909 status = -ENOMEM;
1910 mlog_errno(status);
1911 goto bail;
1912 }
1913
1914 do {
1915 status = dlm_try_to_join_domain(dlm);
1916
1917 /* If we're racing another node to the join, then we
1918 * need to back off temporarily and let them
1919 * complete. */
1920 #define DLM_JOIN_TIMEOUT_MSECS 90000
1921 if (status == -EAGAIN) {
1922 if (signal_pending(current)) {
1923 status = -ERESTARTSYS;
1924 goto bail;
1925 }
1926
1927 if (total_backoff > DLM_JOIN_TIMEOUT_MSECS) {
1928 status = -ERESTARTSYS;
1929 mlog(ML_NOTICE, "Timed out joining dlm domain "
1930 "%s after %u msecs\n", dlm->name,
1931 total_backoff);
1932 goto bail;
1933 }
1934
1935 /*
1936 * <chip> After you!
1937 * <dale> No, after you!
1938 * <chip> I insist!
1939 * <dale> But you first!
1940 * ...
1941 */
1942 backoff = (unsigned int)(jiffies & 0x3);
1943 backoff *= DLM_DOMAIN_BACKOFF_MS;
1944 total_backoff += backoff;
1945 mlog(0, "backoff %d\n", backoff);
1946 msleep(backoff);
1947 }
1948 } while (status == -EAGAIN);
1949
1950 if (status < 0) {
1951 mlog_errno(status);
1952 goto bail;
1953 }
1954
1955 status = 0;
1956 bail:
1957 wake_up(&dlm_domain_events);
1958
1959 if (status) {
1960 dlm_unregister_domain_handlers(dlm);
1961 dlm_debug_shutdown(dlm);
1962 dlm_complete_thread(dlm);
1963 dlm_complete_recovery_thread(dlm);
1964 dlm_destroy_dlm_worker(dlm);
1965 }
1966
1967 return status;
1968 }
1969
1970 static struct dlm_ctxt *dlm_alloc_ctxt(const char *domain,
1971 u32 key)
1972 {
1973 int i;
1974 int ret;
1975 struct dlm_ctxt *dlm = NULL;
1976
1977 dlm = kzalloc(sizeof(*dlm), GFP_KERNEL);
1978 if (!dlm) {
1979 ret = -ENOMEM;
1980 mlog_errno(ret);
1981 goto leave;
1982 }
1983
1984 dlm->name = kstrdup(domain, GFP_KERNEL);
1985 if (dlm->name == NULL) {
1986 ret = -ENOMEM;
1987 mlog_errno(ret);
1988 goto leave;
1989 }
1990
1991 dlm->lockres_hash = (struct hlist_head **)dlm_alloc_pagevec(DLM_HASH_PAGES);
1992 if (!dlm->lockres_hash) {
1993 ret = -ENOMEM;
1994 mlog_errno(ret);
1995 goto leave;
1996 }
1997
1998 for (i = 0; i < DLM_HASH_BUCKETS; i++)
1999 INIT_HLIST_HEAD(dlm_lockres_hash(dlm, i));
2000
2001 dlm->master_hash = (struct hlist_head **)
2002 dlm_alloc_pagevec(DLM_HASH_PAGES);
2003 if (!dlm->master_hash) {
2004 ret = -ENOMEM;
2005 mlog_errno(ret);
2006 goto leave;
2007 }
2008
2009 for (i = 0; i < DLM_HASH_BUCKETS; i++)
2010 INIT_HLIST_HEAD(dlm_master_hash(dlm, i));
2011
2012 dlm->key = key;
2013 dlm->node_num = o2nm_this_node();
2014
2015 ret = dlm_create_debugfs_subroot(dlm);
2016 if (ret < 0)
2017 goto leave;
2018
2019 spin_lock_init(&dlm->spinlock);
2020 spin_lock_init(&dlm->master_lock);
2021 spin_lock_init(&dlm->ast_lock);
2022 spin_lock_init(&dlm->track_lock);
2023 INIT_LIST_HEAD(&dlm->list);
2024 INIT_LIST_HEAD(&dlm->dirty_list);
2025 INIT_LIST_HEAD(&dlm->reco.resources);
2026 INIT_LIST_HEAD(&dlm->reco.node_data);
2027 INIT_LIST_HEAD(&dlm->purge_list);
2028 INIT_LIST_HEAD(&dlm->dlm_domain_handlers);
2029 INIT_LIST_HEAD(&dlm->tracking_list);
2030 dlm->reco.state = 0;
2031
2032 INIT_LIST_HEAD(&dlm->pending_asts);
2033 INIT_LIST_HEAD(&dlm->pending_basts);
2034
2035 mlog(0, "dlm->recovery_map=%p, &(dlm->recovery_map[0])=%p\n",
2036 dlm->recovery_map, &(dlm->recovery_map[0]));
2037
2038 memset(dlm->recovery_map, 0, sizeof(dlm->recovery_map));
2039 memset(dlm->live_nodes_map, 0, sizeof(dlm->live_nodes_map));
2040 memset(dlm->domain_map, 0, sizeof(dlm->domain_map));
2041
2042 dlm->dlm_thread_task = NULL;
2043 dlm->dlm_reco_thread_task = NULL;
2044 dlm->dlm_worker = NULL;
2045 init_waitqueue_head(&dlm->dlm_thread_wq);
2046 init_waitqueue_head(&dlm->dlm_reco_thread_wq);
2047 init_waitqueue_head(&dlm->reco.event);
2048 init_waitqueue_head(&dlm->ast_wq);
2049 init_waitqueue_head(&dlm->migration_wq);
2050 INIT_LIST_HEAD(&dlm->mle_hb_events);
2051
2052 dlm->joining_node = DLM_LOCK_RES_OWNER_UNKNOWN;
2053 init_waitqueue_head(&dlm->dlm_join_events);
2054
2055 dlm->reco.new_master = O2NM_INVALID_NODE_NUM;
2056 dlm->reco.dead_node = O2NM_INVALID_NODE_NUM;
2057
2058 atomic_set(&dlm->res_tot_count, 0);
2059 atomic_set(&dlm->res_cur_count, 0);
2060 for (i = 0; i < DLM_MLE_NUM_TYPES; ++i) {
2061 atomic_set(&dlm->mle_tot_count[i], 0);
2062 atomic_set(&dlm->mle_cur_count[i], 0);
2063 }
2064
2065 spin_lock_init(&dlm->work_lock);
2066 INIT_LIST_HEAD(&dlm->work_list);
2067 INIT_WORK(&dlm->dispatched_work, dlm_dispatch_work);
2068
2069 kref_init(&dlm->dlm_refs);
2070 dlm->dlm_state = DLM_CTXT_NEW;
2071
2072 INIT_LIST_HEAD(&dlm->dlm_eviction_callbacks);
2073
2074 mlog(0, "context init: refcount %u\n",
2075 atomic_read(&dlm->dlm_refs.refcount));
2076
2077 leave:
2078 if (ret < 0 && dlm) {
2079 if (dlm->master_hash)
2080 dlm_free_pagevec((void **)dlm->master_hash,
2081 DLM_HASH_PAGES);
2082
2083 if (dlm->lockres_hash)
2084 dlm_free_pagevec((void **)dlm->lockres_hash,
2085 DLM_HASH_PAGES);
2086
2087 kfree(dlm->name);
2088 kfree(dlm);
2089 dlm = NULL;
2090 }
2091 return dlm;
2092 }
2093
2094 /*
2095 * Compare a requested locking protocol version against the current one.
2096 *
2097 * If the major numbers are different, they are incompatible.
2098 * If the current minor is greater than the request, they are incompatible.
2099 * If the current minor is less than or equal to the request, they are
2100 * compatible, and the requester should run at the current minor version.
2101 */
2102 static int dlm_protocol_compare(struct dlm_protocol_version *existing,
2103 struct dlm_protocol_version *request)
2104 {
2105 if (existing->pv_major != request->pv_major)
2106 return 1;
2107
2108 if (existing->pv_minor > request->pv_minor)
2109 return 1;
2110
2111 if (existing->pv_minor < request->pv_minor)
2112 request->pv_minor = existing->pv_minor;
2113
2114 return 0;
2115 }
2116
2117 /*
2118 * dlm_register_domain: one-time setup per "domain".
2119 *
2120 * The filesystem passes in the requested locking version via proto.
2121 * If registration was successful, proto will contain the negotiated
2122 * locking protocol.
2123 */
2124 struct dlm_ctxt * dlm_register_domain(const char *domain,
2125 u32 key,
2126 struct dlm_protocol_version *fs_proto)
2127 {
2128 int ret;
2129 struct dlm_ctxt *dlm = NULL;
2130 struct dlm_ctxt *new_ctxt = NULL;
2131
2132 if (strlen(domain) >= O2NM_MAX_NAME_LEN) {
2133 ret = -ENAMETOOLONG;
2134 mlog(ML_ERROR, "domain name length too long\n");
2135 goto leave;
2136 }
2137
2138 mlog(0, "register called for domain \"%s\"\n", domain);
2139
2140 retry:
2141 dlm = NULL;
2142 if (signal_pending(current)) {
2143 ret = -ERESTARTSYS;
2144 mlog_errno(ret);
2145 goto leave;
2146 }
2147
2148 spin_lock(&dlm_domain_lock);
2149
2150 dlm = __dlm_lookup_domain(domain);
2151 if (dlm) {
2152 if (dlm->dlm_state != DLM_CTXT_JOINED) {
2153 spin_unlock(&dlm_domain_lock);
2154
2155 mlog(0, "This ctxt is not joined yet!\n");
2156 wait_event_interruptible(dlm_domain_events,
2157 dlm_wait_on_domain_helper(
2158 domain));
2159 goto retry;
2160 }
2161
2162 if (dlm_protocol_compare(&dlm->fs_locking_proto, fs_proto)) {
2163 spin_unlock(&dlm_domain_lock);
2164 mlog(ML_ERROR,
2165 "Requested locking protocol version is not "
2166 "compatible with already registered domain "
2167 "\"%s\"\n", domain);
2168 ret = -EPROTO;
2169 goto leave;
2170 }
2171
2172 __dlm_get(dlm);
2173 dlm->num_joins++;
2174
2175 spin_unlock(&dlm_domain_lock);
2176
2177 ret = 0;
2178 goto leave;
2179 }
2180
2181 /* doesn't exist */
2182 if (!new_ctxt) {
2183 spin_unlock(&dlm_domain_lock);
2184
2185 new_ctxt = dlm_alloc_ctxt(domain, key);
2186 if (new_ctxt)
2187 goto retry;
2188
2189 ret = -ENOMEM;
2190 mlog_errno(ret);
2191 goto leave;
2192 }
2193
2194 /* a little variable switch-a-roo here... */
2195 dlm = new_ctxt;
2196 new_ctxt = NULL;
2197
2198 /* add the new domain */
2199 list_add_tail(&dlm->list, &dlm_domains);
2200 spin_unlock(&dlm_domain_lock);
2201
2202 /*
2203 * Pass the locking protocol version into the join. If the join
2204 * succeeds, it will have the negotiated protocol set.
2205 */
2206 dlm->dlm_locking_proto = dlm_protocol;
2207 dlm->fs_locking_proto = *fs_proto;
2208
2209 ret = dlm_join_domain(dlm);
2210 if (ret) {
2211 mlog_errno(ret);
2212 dlm_put(dlm);
2213 goto leave;
2214 }
2215
2216 /* Tell the caller what locking protocol we negotiated */
2217 *fs_proto = dlm->fs_locking_proto;
2218
2219 ret = 0;
2220 leave:
2221 if (new_ctxt)
2222 dlm_free_ctxt_mem(new_ctxt);
2223
2224 if (ret < 0)
2225 dlm = ERR_PTR(ret);
2226
2227 return dlm;
2228 }
2229 EXPORT_SYMBOL_GPL(dlm_register_domain);
2230
2231 static LIST_HEAD(dlm_join_handlers);
2232
2233 static void dlm_unregister_net_handlers(void)
2234 {
2235 o2net_unregister_handler_list(&dlm_join_handlers);
2236 }
2237
2238 static int dlm_register_net_handlers(void)
2239 {
2240 int status = 0;
2241
2242 status = o2net_register_handler(DLM_QUERY_JOIN_MSG, DLM_MOD_KEY,
2243 sizeof(struct dlm_query_join_request),
2244 dlm_query_join_handler,
2245 NULL, NULL, &dlm_join_handlers);
2246 if (status)
2247 goto bail;
2248
2249 status = o2net_register_handler(DLM_ASSERT_JOINED_MSG, DLM_MOD_KEY,
2250 sizeof(struct dlm_assert_joined),
2251 dlm_assert_joined_handler,
2252 NULL, NULL, &dlm_join_handlers);
2253 if (status)
2254 goto bail;
2255
2256 status = o2net_register_handler(DLM_CANCEL_JOIN_MSG, DLM_MOD_KEY,
2257 sizeof(struct dlm_cancel_join),
2258 dlm_cancel_join_handler,
2259 NULL, NULL, &dlm_join_handlers);
2260 if (status)
2261 goto bail;
2262
2263 status = o2net_register_handler(DLM_QUERY_REGION, DLM_MOD_KEY,
2264 sizeof(struct dlm_query_region),
2265 dlm_query_region_handler,
2266 NULL, NULL, &dlm_join_handlers);
2267
2268 if (status)
2269 goto bail;
2270
2271 status = o2net_register_handler(DLM_QUERY_NODEINFO, DLM_MOD_KEY,
2272 sizeof(struct dlm_query_nodeinfo),
2273 dlm_query_nodeinfo_handler,
2274 NULL, NULL, &dlm_join_handlers);
2275 bail:
2276 if (status < 0)
2277 dlm_unregister_net_handlers();
2278
2279 return status;
2280 }
2281
2282 /* Domain eviction callback handling.
2283 *
2284 * The file system requires notification of node death *before* the
2285 * dlm completes it's recovery work, otherwise it may be able to
2286 * acquire locks on resources requiring recovery. Since the dlm can
2287 * evict a node from it's domain *before* heartbeat fires, a similar
2288 * mechanism is required. */
2289
2290 /* Eviction is not expected to happen often, so a per-domain lock is
2291 * not necessary. Eviction callbacks are allowed to sleep for short
2292 * periods of time. */
2293 static DECLARE_RWSEM(dlm_callback_sem);
2294
2295 void dlm_fire_domain_eviction_callbacks(struct dlm_ctxt *dlm,
2296 int node_num)
2297 {
2298 struct dlm_eviction_cb *cb;
2299
2300 down_read(&dlm_callback_sem);
2301 list_for_each_entry(cb, &dlm->dlm_eviction_callbacks, ec_item) {
2302 cb->ec_func(node_num, cb->ec_data);
2303 }
2304 up_read(&dlm_callback_sem);
2305 }
2306
2307 void dlm_setup_eviction_cb(struct dlm_eviction_cb *cb,
2308 dlm_eviction_func *f,
2309 void *data)
2310 {
2311 INIT_LIST_HEAD(&cb->ec_item);
2312 cb->ec_func = f;
2313 cb->ec_data = data;
2314 }
2315 EXPORT_SYMBOL_GPL(dlm_setup_eviction_cb);
2316
2317 void dlm_register_eviction_cb(struct dlm_ctxt *dlm,
2318 struct dlm_eviction_cb *cb)
2319 {
2320 down_write(&dlm_callback_sem);
2321 list_add_tail(&cb->ec_item, &dlm->dlm_eviction_callbacks);
2322 up_write(&dlm_callback_sem);
2323 }
2324 EXPORT_SYMBOL_GPL(dlm_register_eviction_cb);
2325
2326 void dlm_unregister_eviction_cb(struct dlm_eviction_cb *cb)
2327 {
2328 down_write(&dlm_callback_sem);
2329 list_del_init(&cb->ec_item);
2330 up_write(&dlm_callback_sem);
2331 }
2332 EXPORT_SYMBOL_GPL(dlm_unregister_eviction_cb);
2333
2334 static int __init dlm_init(void)
2335 {
2336 int status;
2337
2338 status = dlm_init_mle_cache();
2339 if (status) {
2340 mlog(ML_ERROR, "Could not create o2dlm_mle slabcache\n");
2341 goto error;
2342 }
2343
2344 status = dlm_init_master_caches();
2345 if (status) {
2346 mlog(ML_ERROR, "Could not create o2dlm_lockres and "
2347 "o2dlm_lockname slabcaches\n");
2348 goto error;
2349 }
2350
2351 status = dlm_init_lock_cache();
2352 if (status) {
2353 mlog(ML_ERROR, "Count not create o2dlm_lock slabcache\n");
2354 goto error;
2355 }
2356
2357 status = dlm_register_net_handlers();
2358 if (status) {
2359 mlog(ML_ERROR, "Unable to register network handlers\n");
2360 goto error;
2361 }
2362
2363 status = dlm_create_debugfs_root();
2364 if (status)
2365 goto error;
2366
2367 return 0;
2368 error:
2369 dlm_unregister_net_handlers();
2370 dlm_destroy_lock_cache();
2371 dlm_destroy_master_caches();
2372 dlm_destroy_mle_cache();
2373 return -1;
2374 }
2375
2376 static void __exit dlm_exit (void)
2377 {
2378 dlm_destroy_debugfs_root();
2379 dlm_unregister_net_handlers();
2380 dlm_destroy_lock_cache();
2381 dlm_destroy_master_caches();
2382 dlm_destroy_mle_cache();
2383 }
2384
2385 MODULE_AUTHOR("Oracle");
2386 MODULE_LICENSE("GPL");
2387 MODULE_DESCRIPTION("OCFS2 Distributed Lock Management");
2388
2389 module_init(dlm_init);
2390 module_exit(dlm_exit);
Linux with added FPC-III support