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qede: Add basic network device support
[linux-2.6/btrfs-unstable.git] / fs / ocfs2 / dlm / dlmdomain.c
blob6918f30d02cd7631634804389ce0f3deade524e2
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 */
136 static const struct dlm_protocol_version dlm_protocol = {
137 .pv_major = 1,
138 .pv_minor = 2,
139 };
140
141 #define DLM_DOMAIN_BACKOFF_MS 200
142
143 static int dlm_query_join_handler(struct o2net_msg *msg, u32 len, void *data,
144 void **ret_data);
145 static int dlm_assert_joined_handler(struct o2net_msg *msg, u32 len, void *data,
146 void **ret_data);
147 static int dlm_cancel_join_handler(struct o2net_msg *msg, u32 len, void *data,
148 void **ret_data);
149 static int dlm_query_region_handler(struct o2net_msg *msg, u32 len,
150 void *data, void **ret_data);
151 static int dlm_exit_domain_handler(struct o2net_msg *msg, u32 len, void *data,
152 void **ret_data);
153 static int dlm_protocol_compare(struct dlm_protocol_version *existing,
154 struct dlm_protocol_version *request);
155
156 static void dlm_unregister_domain_handlers(struct dlm_ctxt *dlm);
157
158 void __dlm_unhash_lockres(struct dlm_ctxt *dlm, struct dlm_lock_resource *res)
159 {
160 if (hlist_unhashed(&res->hash_node))
161 return;
162
163 mlog(0, "%s: Unhash res %.*s\n", dlm->name, res->lockname.len,
164 res->lockname.name);
165 hlist_del_init(&res->hash_node);
166 dlm_lockres_put(res);
167 }
168
169 void __dlm_insert_lockres(struct dlm_ctxt *dlm, struct dlm_lock_resource *res)
170 {
171 struct hlist_head *bucket;
172 struct qstr *q;
173
174 assert_spin_locked(&dlm->spinlock);
175
176 q = &res->lockname;
177 bucket = dlm_lockres_hash(dlm, q->hash);
178
179 /* get a reference for our hashtable */
180 dlm_lockres_get(res);
181
182 hlist_add_head(&res->hash_node, bucket);
183
184 mlog(0, "%s: Hash res %.*s\n", dlm->name, res->lockname.len,
185 res->lockname.name);
186 }
187
188 struct dlm_lock_resource * __dlm_lookup_lockres_full(struct dlm_ctxt *dlm,
189 const char *name,
190 unsigned int len,
191 unsigned int hash)
192 {
193 struct hlist_head *bucket;
194 struct dlm_lock_resource *res;
195
196 mlog(0, "%.*s\n", len, name);
197
198 assert_spin_locked(&dlm->spinlock);
199
200 bucket = dlm_lockres_hash(dlm, hash);
201
202 hlist_for_each_entry(res, bucket, hash_node) {
203 if (res->lockname.name[0] != name[0])
204 continue;
205 if (unlikely(res->lockname.len != len))
206 continue;
207 if (memcmp(res->lockname.name + 1, name + 1, len - 1))
208 continue;
209 dlm_lockres_get(res);
210 return res;
211 }
212 return NULL;
213 }
214
215 /* intended to be called by functions which do not care about lock
216 * resources which are being purged (most net _handler functions).
217 * this will return NULL for any lock resource which is found but
218 * currently in the process of dropping its mastery reference.
219 * use __dlm_lookup_lockres_full when you need the lock resource
220 * regardless (e.g. dlm_get_lock_resource) */
221 struct dlm_lock_resource * __dlm_lookup_lockres(struct dlm_ctxt *dlm,
222 const char *name,
223 unsigned int len,
224 unsigned int hash)
225 {
226 struct dlm_lock_resource *res = NULL;
227
228 mlog(0, "%.*s\n", len, name);
229
230 assert_spin_locked(&dlm->spinlock);
231
232 res = __dlm_lookup_lockres_full(dlm, name, len, hash);
233 if (res) {
234 spin_lock(&res->spinlock);
235 if (res->state & DLM_LOCK_RES_DROPPING_REF) {
236 spin_unlock(&res->spinlock);
237 dlm_lockres_put(res);
238 return NULL;
239 }
240 spin_unlock(&res->spinlock);
241 }
242
243 return res;
244 }
245
246 struct dlm_lock_resource * dlm_lookup_lockres(struct dlm_ctxt *dlm,
247 const char *name,
248 unsigned int len)
249 {
250 struct dlm_lock_resource *res;
251 unsigned int hash = dlm_lockid_hash(name, len);
252
253 spin_lock(&dlm->spinlock);
254 res = __dlm_lookup_lockres(dlm, name, len, hash);
255 spin_unlock(&dlm->spinlock);
256 return res;
257 }
258
259 static struct dlm_ctxt * __dlm_lookup_domain_full(const char *domain, int len)
260 {
261 struct dlm_ctxt *tmp;
262
263 assert_spin_locked(&dlm_domain_lock);
264
265 /* tmp->name here is always NULL terminated,
266 * but domain may not be! */
267 list_for_each_entry(tmp, &dlm_domains, list) {
268 if (strlen(tmp->name) == len &&
269 memcmp(tmp->name, domain, len)==0)
270 return tmp;
271 }
272
273 return NULL;
274 }
275
276 /* For null terminated domain strings ONLY */
277 static struct dlm_ctxt * __dlm_lookup_domain(const char *domain)
278 {
279 assert_spin_locked(&dlm_domain_lock);
280
281 return __dlm_lookup_domain_full(domain, strlen(domain));
282 }
283
284
285 /* returns true on one of two conditions:
286 * 1) the domain does not exist
287 * 2) the domain exists and it's state is "joined" */
288 static int dlm_wait_on_domain_helper(const char *domain)
289 {
290 int ret = 0;
291 struct dlm_ctxt *tmp = NULL;
292
293 spin_lock(&dlm_domain_lock);
294
295 tmp = __dlm_lookup_domain(domain);
296 if (!tmp)
297 ret = 1;
298 else if (tmp->dlm_state == DLM_CTXT_JOINED)
299 ret = 1;
300
301 spin_unlock(&dlm_domain_lock);
302 return ret;
303 }
304
305 static void dlm_free_ctxt_mem(struct dlm_ctxt *dlm)
306 {
307 dlm_destroy_debugfs_subroot(dlm);
308
309 if (dlm->lockres_hash)
310 dlm_free_pagevec((void **)dlm->lockres_hash, DLM_HASH_PAGES);
311
312 if (dlm->master_hash)
313 dlm_free_pagevec((void **)dlm->master_hash, DLM_HASH_PAGES);
314
315 kfree(dlm->name);
316 kfree(dlm);
317 }
318
319 /* A little strange - this function will be called while holding
320 * dlm_domain_lock and is expected to be holding it on the way out. We
321 * will however drop and reacquire it multiple times */
322 static void dlm_ctxt_release(struct kref *kref)
323 {
324 struct dlm_ctxt *dlm;
325
326 dlm = container_of(kref, struct dlm_ctxt, dlm_refs);
327
328 BUG_ON(dlm->num_joins);
329 BUG_ON(dlm->dlm_state == DLM_CTXT_JOINED);
330
331 /* we may still be in the list if we hit an error during join. */
332 list_del_init(&dlm->list);
333
334 spin_unlock(&dlm_domain_lock);
335
336 mlog(0, "freeing memory from domain %s\n", dlm->name);
337
338 wake_up(&dlm_domain_events);
339
340 dlm_free_ctxt_mem(dlm);
341
342 spin_lock(&dlm_domain_lock);
343 }
344
345 void dlm_put(struct dlm_ctxt *dlm)
346 {
347 spin_lock(&dlm_domain_lock);
348 kref_put(&dlm->dlm_refs, dlm_ctxt_release);
349 spin_unlock(&dlm_domain_lock);
350 }
351
352 static void __dlm_get(struct dlm_ctxt *dlm)
353 {
354 kref_get(&dlm->dlm_refs);
355 }
356
357 /* given a questionable reference to a dlm object, gets a reference if
358 * it can find it in the list, otherwise returns NULL in which case
359 * you shouldn't trust your pointer. */
360 struct dlm_ctxt *dlm_grab(struct dlm_ctxt *dlm)
361 {
362 struct dlm_ctxt *target;
363 struct dlm_ctxt *ret = NULL;
364
365 spin_lock(&dlm_domain_lock);
366
367 list_for_each_entry(target, &dlm_domains, list) {
368 if (target == dlm) {
369 __dlm_get(target);
370 ret = target;
371 break;
372 }
373 }
374
375 spin_unlock(&dlm_domain_lock);
376
377 return ret;
378 }
379
380 int dlm_domain_fully_joined(struct dlm_ctxt *dlm)
381 {
382 int ret;
383
384 spin_lock(&dlm_domain_lock);
385 ret = (dlm->dlm_state == DLM_CTXT_JOINED) ||
386 (dlm->dlm_state == DLM_CTXT_IN_SHUTDOWN);
387 spin_unlock(&dlm_domain_lock);
388
389 return ret;
390 }
391
392 static void dlm_destroy_dlm_worker(struct dlm_ctxt *dlm)
393 {
394 if (dlm->dlm_worker) {
395 flush_workqueue(dlm->dlm_worker);
396 destroy_workqueue(dlm->dlm_worker);
397 dlm->dlm_worker = NULL;
398 }
399 }
400
401 static void dlm_complete_dlm_shutdown(struct dlm_ctxt *dlm)
402 {
403 dlm_unregister_domain_handlers(dlm);
404 dlm_debug_shutdown(dlm);
405 dlm_complete_thread(dlm);
406 dlm_complete_recovery_thread(dlm);
407 dlm_destroy_dlm_worker(dlm);
408
409 /* We've left the domain. Now we can take ourselves out of the
410 * list and allow the kref stuff to help us free the
411 * memory. */
412 spin_lock(&dlm_domain_lock);
413 list_del_init(&dlm->list);
414 spin_unlock(&dlm_domain_lock);
415
416 /* Wake up anyone waiting for us to remove this domain */
417 wake_up(&dlm_domain_events);
418 }
419
420 static int dlm_migrate_all_locks(struct dlm_ctxt *dlm)
421 {
422 int i, num, n, ret = 0;
423 struct dlm_lock_resource *res;
424 struct hlist_node *iter;
425 struct hlist_head *bucket;
426 int dropped;
427
428 mlog(0, "Migrating locks from domain %s\n", dlm->name);
429
430 num = 0;
431 spin_lock(&dlm->spinlock);
432 for (i = 0; i < DLM_HASH_BUCKETS; i++) {
433 redo_bucket:
434 n = 0;
435 bucket = dlm_lockres_hash(dlm, i);
436 iter = bucket->first;
437 while (iter) {
438 n++;
439 res = hlist_entry(iter, struct dlm_lock_resource,
440 hash_node);
441 dlm_lockres_get(res);
442 /* migrate, if necessary. this will drop the dlm
443 * spinlock and retake it if it does migration. */
444 dropped = dlm_empty_lockres(dlm, res);
445
446 spin_lock(&res->spinlock);
447 if (dropped)
448 __dlm_lockres_calc_usage(dlm, res);
449 else
450 iter = res->hash_node.next;
451 spin_unlock(&res->spinlock);
452
453 dlm_lockres_put(res);
454
455 if (dropped) {
456 cond_resched_lock(&dlm->spinlock);
457 goto redo_bucket;
458 }
459 }
460 cond_resched_lock(&dlm->spinlock);
461 num += n;
462 }
463 spin_unlock(&dlm->spinlock);
464 wake_up(&dlm->dlm_thread_wq);
465
466 /* let the dlm thread take care of purging, keep scanning until
467 * nothing remains in the hash */
468 if (num) {
469 mlog(0, "%s: %d lock resources in hash last pass\n",
470 dlm->name, num);
471 ret = -EAGAIN;
472 }
473 mlog(0, "DONE Migrating locks from domain %s\n", dlm->name);
474 return ret;
475 }
476
477 static int dlm_no_joining_node(struct dlm_ctxt *dlm)
478 {
479 int ret;
480
481 spin_lock(&dlm->spinlock);
482 ret = dlm->joining_node == DLM_LOCK_RES_OWNER_UNKNOWN;
483 spin_unlock(&dlm->spinlock);
484
485 return ret;
486 }
487
488 static int dlm_begin_exit_domain_handler(struct o2net_msg *msg, u32 len,
489 void *data, void **ret_data)
490 {
491 struct dlm_ctxt *dlm = data;
492 unsigned int node;
493 struct dlm_exit_domain *exit_msg = (struct dlm_exit_domain *) msg->buf;
494
495 if (!dlm_grab(dlm))
496 return 0;
497
498 node = exit_msg->node_idx;
499 mlog(0, "%s: Node %u sent a begin exit domain message\n", dlm->name, node);
500
501 spin_lock(&dlm->spinlock);
502 set_bit(node, dlm->exit_domain_map);
503 spin_unlock(&dlm->spinlock);
504
505 dlm_put(dlm);
506
507 return 0;
508 }
509
510 static void dlm_mark_domain_leaving(struct dlm_ctxt *dlm)
511 {
512 /* Yikes, a double spinlock! I need domain_lock for the dlm
513 * state and the dlm spinlock for join state... Sorry! */
514 again:
515 spin_lock(&dlm_domain_lock);
516 spin_lock(&dlm->spinlock);
517
518 if (dlm->joining_node != DLM_LOCK_RES_OWNER_UNKNOWN) {
519 mlog(0, "Node %d is joining, we wait on it.\n",
520 dlm->joining_node);
521 spin_unlock(&dlm->spinlock);
522 spin_unlock(&dlm_domain_lock);
523
524 wait_event(dlm->dlm_join_events, dlm_no_joining_node(dlm));
525 goto again;
526 }
527
528 dlm->dlm_state = DLM_CTXT_LEAVING;
529 spin_unlock(&dlm->spinlock);
530 spin_unlock(&dlm_domain_lock);
531 }
532
533 static void __dlm_print_nodes(struct dlm_ctxt *dlm)
534 {
535 int node = -1, num = 0;
536
537 assert_spin_locked(&dlm->spinlock);
538
539 printk("( ");
540 while ((node = find_next_bit(dlm->domain_map, O2NM_MAX_NODES,
541 node + 1)) < O2NM_MAX_NODES) {
542 printk("%d ", node);
543 ++num;
544 }
545 printk(") %u nodes\n", num);
546 }
547
548 static int dlm_exit_domain_handler(struct o2net_msg *msg, u32 len, void *data,
549 void **ret_data)
550 {
551 struct dlm_ctxt *dlm = data;
552 unsigned int node;
553 struct dlm_exit_domain *exit_msg = (struct dlm_exit_domain *) msg->buf;
554
555 mlog(0, "%p %u %p", msg, len, data);
556
557 if (!dlm_grab(dlm))
558 return 0;
559
560 node = exit_msg->node_idx;
561
562 spin_lock(&dlm->spinlock);
563 clear_bit(node, dlm->domain_map);
564 clear_bit(node, dlm->exit_domain_map);
565 printk(KERN_NOTICE "o2dlm: Node %u leaves domain %s ", node, dlm->name);
566 __dlm_print_nodes(dlm);
567
568 /* notify anything attached to the heartbeat events */
569 dlm_hb_event_notify_attached(dlm, node, 0);
570
571 spin_unlock(&dlm->spinlock);
572
573 dlm_put(dlm);
574
575 return 0;
576 }
577
578 static int dlm_send_one_domain_exit(struct dlm_ctxt *dlm, u32 msg_type,
579 unsigned int node)
580 {
581 int status;
582 struct dlm_exit_domain leave_msg;
583
584 mlog(0, "%s: Sending domain exit message %u to node %u\n", dlm->name,
585 msg_type, node);
586
587 memset(&leave_msg, 0, sizeof(leave_msg));
588 leave_msg.node_idx = dlm->node_num;
589
590 status = o2net_send_message(msg_type, dlm->key, &leave_msg,
591 sizeof(leave_msg), node, NULL);
592 if (status < 0)
593 mlog(ML_ERROR, "Error %d sending domain exit message %u "
594 "to node %u on domain %s\n", status, msg_type, node,
595 dlm->name);
596
597 return status;
598 }
599
600 static void dlm_begin_exit_domain(struct dlm_ctxt *dlm)
601 {
602 int node = -1;
603
604 /* Support for begin exit domain was added in 1.2 */
605 if (dlm->dlm_locking_proto.pv_major == 1 &&
606 dlm->dlm_locking_proto.pv_minor < 2)
607 return;
608
609 /*
610 * Unlike DLM_EXIT_DOMAIN_MSG, DLM_BEGIN_EXIT_DOMAIN_MSG is purely
611 * informational. Meaning if a node does not receive the message,
612 * so be it.
613 */
614 spin_lock(&dlm->spinlock);
615 while (1) {
616 node = find_next_bit(dlm->domain_map, O2NM_MAX_NODES, node + 1);
617 if (node >= O2NM_MAX_NODES)
618 break;
619 if (node == dlm->node_num)
620 continue;
621
622 spin_unlock(&dlm->spinlock);
623 dlm_send_one_domain_exit(dlm, DLM_BEGIN_EXIT_DOMAIN_MSG, node);
624 spin_lock(&dlm->spinlock);
625 }
626 spin_unlock(&dlm->spinlock);
627 }
628
629 static void dlm_leave_domain(struct dlm_ctxt *dlm)
630 {
631 int node, clear_node, status;
632
633 /* At this point we've migrated away all our locks and won't
634 * accept mastership of new ones. The dlm is responsible for
635 * almost nothing now. We make sure not to confuse any joining
636 * nodes and then commence shutdown procedure. */
637
638 spin_lock(&dlm->spinlock);
639 /* Clear ourselves from the domain map */
640 clear_bit(dlm->node_num, dlm->domain_map);
641 while ((node = find_next_bit(dlm->domain_map, O2NM_MAX_NODES,
642 0)) < O2NM_MAX_NODES) {
643 /* Drop the dlm spinlock. This is safe wrt the domain_map.
644 * -nodes cannot be added now as the
645 * query_join_handlers knows to respond with OK_NO_MAP
646 * -we catch the right network errors if a node is
647 * removed from the map while we're sending him the
648 * exit message. */
649 spin_unlock(&dlm->spinlock);
650
651 clear_node = 1;
652
653 status = dlm_send_one_domain_exit(dlm, DLM_EXIT_DOMAIN_MSG,
654 node);
655 if (status < 0 &&
656 status != -ENOPROTOOPT &&
657 status != -ENOTCONN) {
658 mlog(ML_NOTICE, "Error %d sending domain exit message "
659 "to node %d\n", status, node);
660
661 /* Not sure what to do here but lets sleep for
662 * a bit in case this was a transient
663 * error... */
664 msleep(DLM_DOMAIN_BACKOFF_MS);
665 clear_node = 0;
666 }
667
668 spin_lock(&dlm->spinlock);
669 /* If we're not clearing the node bit then we intend
670 * to loop back around to try again. */
671 if (clear_node)
672 clear_bit(node, dlm->domain_map);
673 }
674 spin_unlock(&dlm->spinlock);
675 }
676
677 int dlm_shutting_down(struct dlm_ctxt *dlm)
678 {
679 int ret = 0;
680
681 spin_lock(&dlm_domain_lock);
682
683 if (dlm->dlm_state == DLM_CTXT_IN_SHUTDOWN)
684 ret = 1;
685
686 spin_unlock(&dlm_domain_lock);
687
688 return ret;
689 }
690
691 void dlm_unregister_domain(struct dlm_ctxt *dlm)
692 {
693 int leave = 0;
694 struct dlm_lock_resource *res;
695
696 spin_lock(&dlm_domain_lock);
697 BUG_ON(dlm->dlm_state != DLM_CTXT_JOINED);
698 BUG_ON(!dlm->num_joins);
699
700 dlm->num_joins--;
701 if (!dlm->num_joins) {
702 /* We mark it "in shutdown" now so new register
703 * requests wait until we've completely left the
704 * domain. Don't use DLM_CTXT_LEAVING yet as we still
705 * want new domain joins to communicate with us at
706 * least until we've completed migration of our
707 * resources. */
708 dlm->dlm_state = DLM_CTXT_IN_SHUTDOWN;
709 leave = 1;
710 }
711 spin_unlock(&dlm_domain_lock);
712
713 if (leave) {
714 mlog(0, "shutting down domain %s\n", dlm->name);
715 dlm_begin_exit_domain(dlm);
716
717 /* We changed dlm state, notify the thread */
718 dlm_kick_thread(dlm, NULL);
719
720 while (dlm_migrate_all_locks(dlm)) {
721 /* Give dlm_thread time to purge the lockres' */
722 msleep(500);
723 mlog(0, "%s: more migration to do\n", dlm->name);
724 }
725
726 /* This list should be empty. If not, print remaining lockres */
727 if (!list_empty(&dlm->tracking_list)) {
728 mlog(ML_ERROR, "Following lockres' are still on the "
729 "tracking list:\n");
730 list_for_each_entry(res, &dlm->tracking_list, tracking)
731 dlm_print_one_lock_resource(res);
732 }
733
734 dlm_mark_domain_leaving(dlm);
735 dlm_leave_domain(dlm);
736 printk(KERN_NOTICE "o2dlm: Leaving domain %s\n", dlm->name);
737 dlm_force_free_mles(dlm);
738 dlm_complete_dlm_shutdown(dlm);
739 }
740 dlm_put(dlm);
741 }
742 EXPORT_SYMBOL_GPL(dlm_unregister_domain);
743
744 static int dlm_query_join_proto_check(char *proto_type, int node,
745 struct dlm_protocol_version *ours,
746 struct dlm_protocol_version *request)
747 {
748 int rc;
749 struct dlm_protocol_version proto = *request;
750
751 if (!dlm_protocol_compare(ours, &proto)) {
752 mlog(0,
753 "node %u wanted to join with %s locking protocol "
754 "%u.%u, we respond with %u.%u\n",
755 node, proto_type,
756 request->pv_major,
757 request->pv_minor,
758 proto.pv_major, proto.pv_minor);
759 request->pv_minor = proto.pv_minor;
760 rc = 0;
761 } else {
762 mlog(ML_NOTICE,
763 "Node %u wanted to join with %s locking "
764 "protocol %u.%u, but we have %u.%u, disallowing\n",
765 node, proto_type,
766 request->pv_major,
767 request->pv_minor,
768 ours->pv_major,
769 ours->pv_minor);
770 rc = 1;
771 }
772
773 return rc;
774 }
775
776 /*
777 * struct dlm_query_join_packet is made up of four one-byte fields. They
778 * are effectively in big-endian order already. However, little-endian
779 * machines swap them before putting the packet on the wire (because
780 * query_join's response is a status, and that status is treated as a u32
781 * on the wire). Thus, a big-endian and little-endian machines will treat
782 * this structure differently.
783 *
784 * The solution is to have little-endian machines swap the structure when
785 * converting from the structure to the u32 representation. This will
786 * result in the structure having the correct format on the wire no matter
787 * the host endian format.
788 */
789 static void dlm_query_join_packet_to_wire(struct dlm_query_join_packet *packet,
790 u32 *wire)
791 {
792 union dlm_query_join_response response;
793
794 response.packet = *packet;
795 *wire = be32_to_cpu(response.intval);
796 }
797
798 static void dlm_query_join_wire_to_packet(u32 wire,
799 struct dlm_query_join_packet *packet)
800 {
801 union dlm_query_join_response response;
802
803 response.intval = cpu_to_be32(wire);
804 *packet = response.packet;
805 }
806
807 static int dlm_query_join_handler(struct o2net_msg *msg, u32 len, void *data,
808 void **ret_data)
809 {
810 struct dlm_query_join_request *query;
811 struct dlm_query_join_packet packet = {
812 .code = JOIN_DISALLOW,
813 };
814 struct dlm_ctxt *dlm = NULL;
815 u32 response;
816 u8 nodenum;
817
818 query = (struct dlm_query_join_request *) msg->buf;
819
820 mlog(0, "node %u wants to join domain %s\n", query->node_idx,
821 query->domain);
822
823 /*
824 * If heartbeat doesn't consider the node live, tell it
825 * to back off and try again. This gives heartbeat a chance
826 * to catch up.
827 */
828 if (!o2hb_check_node_heartbeating_no_sem(query->node_idx)) {
829 mlog(0, "node %u is not in our live map yet\n",
830 query->node_idx);
831
832 packet.code = JOIN_DISALLOW;
833 goto respond;
834 }
835
836 packet.code = JOIN_OK_NO_MAP;
837
838 spin_lock(&dlm_domain_lock);
839 dlm = __dlm_lookup_domain_full(query->domain, query->name_len);
840 if (!dlm)
841 goto unlock_respond;
842
843 /*
844 * There is a small window where the joining node may not see the
845 * node(s) that just left but still part of the cluster. DISALLOW
846 * join request if joining node has different node map.
847 */
848 nodenum=0;
849 while (nodenum < O2NM_MAX_NODES) {
850 if (test_bit(nodenum, dlm->domain_map)) {
851 if (!byte_test_bit(nodenum, query->node_map)) {
852 mlog(0, "disallow join as node %u does not "
853 "have node %u in its nodemap\n",
854 query->node_idx, nodenum);
855 packet.code = JOIN_DISALLOW;
856 goto unlock_respond;
857 }
858 }
859 nodenum++;
860 }
861
862 /* Once the dlm ctxt is marked as leaving then we don't want
863 * to be put in someone's domain map.
864 * Also, explicitly disallow joining at certain troublesome
865 * times (ie. during recovery). */
866 if (dlm->dlm_state != DLM_CTXT_LEAVING) {
867 int bit = query->node_idx;
868 spin_lock(&dlm->spinlock);
869
870 if (dlm->dlm_state == DLM_CTXT_NEW &&
871 dlm->joining_node == DLM_LOCK_RES_OWNER_UNKNOWN) {
872 /*If this is a brand new context and we
873 * haven't started our join process yet, then
874 * the other node won the race. */
875 packet.code = JOIN_OK_NO_MAP;
876 } else if (dlm->joining_node != DLM_LOCK_RES_OWNER_UNKNOWN) {
877 /* Disallow parallel joins. */
878 packet.code = JOIN_DISALLOW;
879 } else if (dlm->reco.state & DLM_RECO_STATE_ACTIVE) {
880 mlog(0, "node %u trying to join, but recovery "
881 "is ongoing.\n", bit);
882 packet.code = JOIN_DISALLOW;
883 } else if (test_bit(bit, dlm->recovery_map)) {
884 mlog(0, "node %u trying to join, but it "
885 "still needs recovery.\n", bit);
886 packet.code = JOIN_DISALLOW;
887 } else if (test_bit(bit, dlm->domain_map)) {
888 mlog(0, "node %u trying to join, but it "
889 "is still in the domain! needs recovery?\n",
890 bit);
891 packet.code = JOIN_DISALLOW;
892 } else {
893 /* Alright we're fully a part of this domain
894 * so we keep some state as to who's joining
895 * and indicate to him that needs to be fixed
896 * up. */
897
898 /* Make sure we speak compatible locking protocols. */
899 if (dlm_query_join_proto_check("DLM", bit,
900 &dlm->dlm_locking_proto,
901 &query->dlm_proto)) {
902 packet.code = JOIN_PROTOCOL_MISMATCH;
903 } else if (dlm_query_join_proto_check("fs", bit,
904 &dlm->fs_locking_proto,
905 &query->fs_proto)) {
906 packet.code = JOIN_PROTOCOL_MISMATCH;
907 } else {
908 packet.dlm_minor = query->dlm_proto.pv_minor;
909 packet.fs_minor = query->fs_proto.pv_minor;
910 packet.code = JOIN_OK;
911 __dlm_set_joining_node(dlm, query->node_idx);
912 }
913 }
914
915 spin_unlock(&dlm->spinlock);
916 }
917 unlock_respond:
918 spin_unlock(&dlm_domain_lock);
919
920 respond:
921 mlog(0, "We respond with %u\n", packet.code);
922
923 dlm_query_join_packet_to_wire(&packet, &response);
924 return response;
925 }
926
927 static int dlm_assert_joined_handler(struct o2net_msg *msg, u32 len, void *data,
928 void **ret_data)
929 {
930 struct dlm_assert_joined *assert;
931 struct dlm_ctxt *dlm = NULL;
932
933 assert = (struct dlm_assert_joined *) msg->buf;
934
935 mlog(0, "node %u asserts join on domain %s\n", assert->node_idx,
936 assert->domain);
937
938 spin_lock(&dlm_domain_lock);
939 dlm = __dlm_lookup_domain_full(assert->domain, assert->name_len);
940 /* XXX should we consider no dlm ctxt an error? */
941 if (dlm) {
942 spin_lock(&dlm->spinlock);
943
944 /* Alright, this node has officially joined our
945 * domain. Set him in the map and clean up our
946 * leftover join state. */
947 BUG_ON(dlm->joining_node != assert->node_idx);
948
949 if (dlm->reco.state & DLM_RECO_STATE_ACTIVE) {
950 mlog(0, "dlm recovery is ongoing, disallow join\n");
951 spin_unlock(&dlm->spinlock);
952 spin_unlock(&dlm_domain_lock);
953 return -EAGAIN;
954 }
955
956 set_bit(assert->node_idx, dlm->domain_map);
957 clear_bit(assert->node_idx, dlm->exit_domain_map);
958 __dlm_set_joining_node(dlm, DLM_LOCK_RES_OWNER_UNKNOWN);
959
960 printk(KERN_NOTICE "o2dlm: Node %u joins domain %s ",
961 assert->node_idx, dlm->name);
962 __dlm_print_nodes(dlm);
963
964 /* notify anything attached to the heartbeat events */
965 dlm_hb_event_notify_attached(dlm, assert->node_idx, 1);
966
967 spin_unlock(&dlm->spinlock);
968 }
969 spin_unlock(&dlm_domain_lock);
970
971 return 0;
972 }
973
974 static int dlm_match_regions(struct dlm_ctxt *dlm,
975 struct dlm_query_region *qr,
976 char *local, int locallen)
977 {
978 char *remote = qr->qr_regions;
979 char *l, *r;
980 int localnr, i, j, foundit;
981 int status = 0;
982
983 if (!o2hb_global_heartbeat_active()) {
984 if (qr->qr_numregions) {
985 mlog(ML_ERROR, "Domain %s: Joining node %d has global "
986 "heartbeat enabled but local node %d does not\n",
987 qr->qr_domain, qr->qr_node, dlm->node_num);
988 status = -EINVAL;
989 }
990 goto bail;
991 }
992
993 if (o2hb_global_heartbeat_active() && !qr->qr_numregions) {
994 mlog(ML_ERROR, "Domain %s: Local node %d has global "
995 "heartbeat enabled but joining node %d does not\n",
996 qr->qr_domain, dlm->node_num, qr->qr_node);
997 status = -EINVAL;
998 goto bail;
999 }
1000
1001 r = remote;
1002 for (i = 0; i < qr->qr_numregions; ++i) {
1003 mlog(0, "Region %.*s\n", O2HB_MAX_REGION_NAME_LEN, r);
1004 r += O2HB_MAX_REGION_NAME_LEN;
1005 }
1006
1007 localnr = min(O2NM_MAX_REGIONS, locallen/O2HB_MAX_REGION_NAME_LEN);
1008 localnr = o2hb_get_all_regions(local, (u8)localnr);
1009
1010 /* compare local regions with remote */
1011 l = local;
1012 for (i = 0; i < localnr; ++i) {
1013 foundit = 0;
1014 r = remote;
1015 for (j = 0; j <= qr->qr_numregions; ++j) {
1016 if (!memcmp(l, r, O2HB_MAX_REGION_NAME_LEN)) {
1017 foundit = 1;
1018 break;
1019 }
1020 r += O2HB_MAX_REGION_NAME_LEN;
1021 }
1022 if (!foundit) {
1023 status = -EINVAL;
1024 mlog(ML_ERROR, "Domain %s: Region '%.*s' registered "
1025 "in local node %d but not in joining node %d\n",
1026 qr->qr_domain, O2HB_MAX_REGION_NAME_LEN, l,
1027 dlm->node_num, qr->qr_node);
1028 goto bail;
1029 }
1030 l += O2HB_MAX_REGION_NAME_LEN;
1031 }
1032
1033 /* compare remote with local regions */
1034 r = remote;
1035 for (i = 0; i < qr->qr_numregions; ++i) {
1036 foundit = 0;
1037 l = local;
1038 for (j = 0; j < localnr; ++j) {
1039 if (!memcmp(r, l, O2HB_MAX_REGION_NAME_LEN)) {
1040 foundit = 1;
1041 break;
1042 }
1043 l += O2HB_MAX_REGION_NAME_LEN;
1044 }
1045 if (!foundit) {
1046 status = -EINVAL;
1047 mlog(ML_ERROR, "Domain %s: Region '%.*s' registered "
1048 "in joining node %d but not in local node %d\n",
1049 qr->qr_domain, O2HB_MAX_REGION_NAME_LEN, r,
1050 qr->qr_node, dlm->node_num);
1051 goto bail;
1052 }
1053 r += O2HB_MAX_REGION_NAME_LEN;
1054 }
1055
1056 bail:
1057 return status;
1058 }
1059
1060 static int dlm_send_regions(struct dlm_ctxt *dlm, unsigned long *node_map)
1061 {
1062 struct dlm_query_region *qr = NULL;
1063 int status, ret = 0, i;
1064 char *p;
1065
1066 if (find_next_bit(node_map, O2NM_MAX_NODES, 0) >= O2NM_MAX_NODES)
1067 goto bail;
1068
1069 qr = kzalloc(sizeof(struct dlm_query_region), GFP_KERNEL);
1070 if (!qr) {
1071 ret = -ENOMEM;
1072 mlog_errno(ret);
1073 goto bail;
1074 }
1075
1076 qr->qr_node = dlm->node_num;
1077 qr->qr_namelen = strlen(dlm->name);
1078 memcpy(qr->qr_domain, dlm->name, qr->qr_namelen);
1079 /* if local hb, the numregions will be zero */
1080 if (o2hb_global_heartbeat_active())
1081 qr->qr_numregions = o2hb_get_all_regions(qr->qr_regions,
1082 O2NM_MAX_REGIONS);
1083
1084 p = qr->qr_regions;
1085 for (i = 0; i < qr->qr_numregions; ++i, p += O2HB_MAX_REGION_NAME_LEN)
1086 mlog(0, "Region %.*s\n", O2HB_MAX_REGION_NAME_LEN, p);
1087
1088 i = -1;
1089 while ((i = find_next_bit(node_map, O2NM_MAX_NODES,
1090 i + 1)) < O2NM_MAX_NODES) {
1091 if (i == dlm->node_num)
1092 continue;
1093
1094 mlog(0, "Sending regions to node %d\n", i);
1095
1096 ret = o2net_send_message(DLM_QUERY_REGION, DLM_MOD_KEY, qr,
1097 sizeof(struct dlm_query_region),
1098 i, &status);
1099 if (ret >= 0)
1100 ret = status;
1101 if (ret) {
1102 mlog(ML_ERROR, "Region mismatch %d, node %d\n",
1103 ret, i);
1104 break;
1105 }
1106 }
1107
1108 bail:
1109 kfree(qr);
1110 return ret;
1111 }
1112
1113 static int dlm_query_region_handler(struct o2net_msg *msg, u32 len,
1114 void *data, void **ret_data)
1115 {
1116 struct dlm_query_region *qr;
1117 struct dlm_ctxt *dlm = NULL;
1118 char *local = NULL;
1119 int status = 0;
1120
1121 qr = (struct dlm_query_region *) msg->buf;
1122
1123 mlog(0, "Node %u queries hb regions on domain %s\n", qr->qr_node,
1124 qr->qr_domain);
1125
1126 /* buffer used in dlm_mast_regions() */
1127 local = kmalloc(sizeof(qr->qr_regions), GFP_KERNEL);
1128 if (!local)
1129 return -ENOMEM;
1130
1131 status = -EINVAL;
1132
1133 spin_lock(&dlm_domain_lock);
1134 dlm = __dlm_lookup_domain_full(qr->qr_domain, qr->qr_namelen);
1135 if (!dlm) {
1136 mlog(ML_ERROR, "Node %d queried hb regions on domain %s "
1137 "before join domain\n", qr->qr_node, qr->qr_domain);
1138 goto out_domain_lock;
1139 }
1140
1141 spin_lock(&dlm->spinlock);
1142 if (dlm->joining_node != qr->qr_node) {
1143 mlog(ML_ERROR, "Node %d queried hb regions on domain %s "
1144 "but joining node is %d\n", qr->qr_node, qr->qr_domain,
1145 dlm->joining_node);
1146 goto out_dlm_lock;
1147 }
1148
1149 /* Support for global heartbeat was added in 1.1 */
1150 if (dlm->dlm_locking_proto.pv_major == 1 &&
1151 dlm->dlm_locking_proto.pv_minor == 0) {
1152 mlog(ML_ERROR, "Node %d queried hb regions on domain %s "
1153 "but active dlm protocol is %d.%d\n", qr->qr_node,
1154 qr->qr_domain, dlm->dlm_locking_proto.pv_major,
1155 dlm->dlm_locking_proto.pv_minor);
1156 goto out_dlm_lock;
1157 }
1158
1159 status = dlm_match_regions(dlm, qr, local, sizeof(qr->qr_regions));
1160
1161 out_dlm_lock:
1162 spin_unlock(&dlm->spinlock);
1163
1164 out_domain_lock:
1165 spin_unlock(&dlm_domain_lock);
1166
1167 kfree(local);
1168
1169 return status;
1170 }
1171
1172 static int dlm_match_nodes(struct dlm_ctxt *dlm, struct dlm_query_nodeinfo *qn)
1173 {
1174 struct o2nm_node *local;
1175 struct dlm_node_info *remote;
1176 int i, j;
1177 int status = 0;
1178
1179 for (j = 0; j < qn->qn_numnodes; ++j)
1180 mlog(0, "Node %3d, %pI4:%u\n", qn->qn_nodes[j].ni_nodenum,
1181 &(qn->qn_nodes[j].ni_ipv4_address),
1182 ntohs(qn->qn_nodes[j].ni_ipv4_port));
1183
1184 for (i = 0; i < O2NM_MAX_NODES && !status; ++i) {
1185 local = o2nm_get_node_by_num(i);
1186 remote = NULL;
1187 for (j = 0; j < qn->qn_numnodes; ++j) {
1188 if (qn->qn_nodes[j].ni_nodenum == i) {
1189 remote = &(qn->qn_nodes[j]);
1190 break;
1191 }
1192 }
1193
1194 if (!local && !remote)
1195 continue;
1196
1197 if ((local && !remote) || (!local && remote))
1198 status = -EINVAL;
1199
1200 if (!status &&
1201 ((remote->ni_nodenum != local->nd_num) ||
1202 (remote->ni_ipv4_port != local->nd_ipv4_port) ||
1203 (remote->ni_ipv4_address != local->nd_ipv4_address)))
1204 status = -EINVAL;
1205
1206 if (status) {
1207 if (remote && !local)
1208 mlog(ML_ERROR, "Domain %s: Node %d (%pI4:%u) "
1209 "registered in joining node %d but not in "
1210 "local node %d\n", qn->qn_domain,
1211 remote->ni_nodenum,
1212 &(remote->ni_ipv4_address),
1213 ntohs(remote->ni_ipv4_port),
1214 qn->qn_nodenum, dlm->node_num);
1215 if (local && !remote)
1216 mlog(ML_ERROR, "Domain %s: Node %d (%pI4:%u) "
1217 "registered in local node %d but not in "
1218 "joining node %d\n", qn->qn_domain,
1219 local->nd_num, &(local->nd_ipv4_address),
1220 ntohs(local->nd_ipv4_port),
1221 dlm->node_num, qn->qn_nodenum);
1222 BUG_ON((!local && !remote));
1223 }
1224
1225 if (local)
1226 o2nm_node_put(local);
1227 }
1228
1229 return status;
1230 }
1231
1232 static int dlm_send_nodeinfo(struct dlm_ctxt *dlm, unsigned long *node_map)
1233 {
1234 struct dlm_query_nodeinfo *qn = NULL;
1235 struct o2nm_node *node;
1236 int ret = 0, status, count, i;
1237
1238 if (find_next_bit(node_map, O2NM_MAX_NODES, 0) >= O2NM_MAX_NODES)
1239 goto bail;
1240
1241 qn = kzalloc(sizeof(struct dlm_query_nodeinfo), GFP_KERNEL);
1242 if (!qn) {
1243 ret = -ENOMEM;
1244 mlog_errno(ret);
1245 goto bail;
1246 }
1247
1248 for (i = 0, count = 0; i < O2NM_MAX_NODES; ++i) {
1249 node = o2nm_get_node_by_num(i);
1250 if (!node)
1251 continue;
1252 qn->qn_nodes[count].ni_nodenum = node->nd_num;
1253 qn->qn_nodes[count].ni_ipv4_port = node->nd_ipv4_port;
1254 qn->qn_nodes[count].ni_ipv4_address = node->nd_ipv4_address;
1255 mlog(0, "Node %3d, %pI4:%u\n", node->nd_num,
1256 &(node->nd_ipv4_address), ntohs(node->nd_ipv4_port));
1257 ++count;
1258 o2nm_node_put(node);
1259 }
1260
1261 qn->qn_nodenum = dlm->node_num;
1262 qn->qn_numnodes = count;
1263 qn->qn_namelen = strlen(dlm->name);
1264 memcpy(qn->qn_domain, dlm->name, qn->qn_namelen);
1265
1266 i = -1;
1267 while ((i = find_next_bit(node_map, O2NM_MAX_NODES,
1268 i + 1)) < O2NM_MAX_NODES) {
1269 if (i == dlm->node_num)
1270 continue;
1271
1272 mlog(0, "Sending nodeinfo to node %d\n", i);
1273
1274 ret = o2net_send_message(DLM_QUERY_NODEINFO, DLM_MOD_KEY,
1275 qn, sizeof(struct dlm_query_nodeinfo),
1276 i, &status);
1277 if (ret >= 0)
1278 ret = status;
1279 if (ret) {
1280 mlog(ML_ERROR, "node mismatch %d, node %d\n", ret, i);
1281 break;
1282 }
1283 }
1284
1285 bail:
1286 kfree(qn);
1287 return ret;
1288 }
1289
1290 static int dlm_query_nodeinfo_handler(struct o2net_msg *msg, u32 len,
1291 void *data, void **ret_data)
1292 {
1293 struct dlm_query_nodeinfo *qn;
1294 struct dlm_ctxt *dlm = NULL;
1295 int locked = 0, status = -EINVAL;
1296
1297 qn = (struct dlm_query_nodeinfo *) msg->buf;
1298
1299 mlog(0, "Node %u queries nodes on domain %s\n", qn->qn_nodenum,
1300 qn->qn_domain);
1301
1302 spin_lock(&dlm_domain_lock);
1303 dlm = __dlm_lookup_domain_full(qn->qn_domain, qn->qn_namelen);
1304 if (!dlm) {
1305 mlog(ML_ERROR, "Node %d queried nodes on domain %s before "
1306 "join domain\n", qn->qn_nodenum, qn->qn_domain);
1307 goto bail;
1308 }
1309
1310 spin_lock(&dlm->spinlock);
1311 locked = 1;
1312 if (dlm->joining_node != qn->qn_nodenum) {
1313 mlog(ML_ERROR, "Node %d queried nodes on domain %s but "
1314 "joining node is %d\n", qn->qn_nodenum, qn->qn_domain,
1315 dlm->joining_node);
1316 goto bail;
1317 }
1318
1319 /* Support for node query was added in 1.1 */
1320 if (dlm->dlm_locking_proto.pv_major == 1 &&
1321 dlm->dlm_locking_proto.pv_minor == 0) {
1322 mlog(ML_ERROR, "Node %d queried nodes on domain %s "
1323 "but active dlm protocol is %d.%d\n", qn->qn_nodenum,
1324 qn->qn_domain, dlm->dlm_locking_proto.pv_major,
1325 dlm->dlm_locking_proto.pv_minor);
1326 goto bail;
1327 }
1328
1329 status = dlm_match_nodes(dlm, qn);
1330
1331 bail:
1332 if (locked)
1333 spin_unlock(&dlm->spinlock);
1334 spin_unlock(&dlm_domain_lock);
1335
1336 return status;
1337 }
1338
1339 static int dlm_cancel_join_handler(struct o2net_msg *msg, u32 len, void *data,
1340 void **ret_data)
1341 {
1342 struct dlm_cancel_join *cancel;
1343 struct dlm_ctxt *dlm = NULL;
1344
1345 cancel = (struct dlm_cancel_join *) msg->buf;
1346
1347 mlog(0, "node %u cancels join on domain %s\n", cancel->node_idx,
1348 cancel->domain);
1349
1350 spin_lock(&dlm_domain_lock);
1351 dlm = __dlm_lookup_domain_full(cancel->domain, cancel->name_len);
1352
1353 if (dlm) {
1354 spin_lock(&dlm->spinlock);
1355
1356 /* Yikes, this guy wants to cancel his join. No
1357 * problem, we simply cleanup our join state. */
1358 BUG_ON(dlm->joining_node != cancel->node_idx);
1359 __dlm_set_joining_node(dlm, DLM_LOCK_RES_OWNER_UNKNOWN);
1360
1361 spin_unlock(&dlm->spinlock);
1362 }
1363 spin_unlock(&dlm_domain_lock);
1364
1365 return 0;
1366 }
1367
1368 static int dlm_send_one_join_cancel(struct dlm_ctxt *dlm,
1369 unsigned int node)
1370 {
1371 int status;
1372 struct dlm_cancel_join cancel_msg;
1373
1374 memset(&cancel_msg, 0, sizeof(cancel_msg));
1375 cancel_msg.node_idx = dlm->node_num;
1376 cancel_msg.name_len = strlen(dlm->name);
1377 memcpy(cancel_msg.domain, dlm->name, cancel_msg.name_len);
1378
1379 status = o2net_send_message(DLM_CANCEL_JOIN_MSG, DLM_MOD_KEY,
1380 &cancel_msg, sizeof(cancel_msg), node,
1381 NULL);
1382 if (status < 0) {
1383 mlog(ML_ERROR, "Error %d when sending message %u (key 0x%x) to "
1384 "node %u\n", status, DLM_CANCEL_JOIN_MSG, DLM_MOD_KEY,
1385 node);
1386 goto bail;
1387 }
1388
1389 bail:
1390 return status;
1391 }
1392
1393 /* map_size should be in bytes. */
1394 static int dlm_send_join_cancels(struct dlm_ctxt *dlm,
1395 unsigned long *node_map,
1396 unsigned int map_size)
1397 {
1398 int status, tmpstat;
1399 unsigned int node;
1400
1401 if (map_size != (BITS_TO_LONGS(O2NM_MAX_NODES) *
1402 sizeof(unsigned long))) {
1403 mlog(ML_ERROR,
1404 "map_size %u != BITS_TO_LONGS(O2NM_MAX_NODES) %u\n",
1405 map_size, (unsigned)BITS_TO_LONGS(O2NM_MAX_NODES));
1406 return -EINVAL;
1407 }
1408
1409 status = 0;
1410 node = -1;
1411 while ((node = find_next_bit(node_map, O2NM_MAX_NODES,
1412 node + 1)) < O2NM_MAX_NODES) {
1413 if (node == dlm->node_num)
1414 continue;
1415
1416 tmpstat = dlm_send_one_join_cancel(dlm, node);
1417 if (tmpstat) {
1418 mlog(ML_ERROR, "Error return %d cancelling join on "
1419 "node %d\n", tmpstat, node);
1420 if (!status)
1421 status = tmpstat;
1422 }
1423 }
1424
1425 if (status)
1426 mlog_errno(status);
1427 return status;
1428 }
1429
1430 static int dlm_request_join(struct dlm_ctxt *dlm,
1431 int node,
1432 enum dlm_query_join_response_code *response)
1433 {
1434 int status;
1435 struct dlm_query_join_request join_msg;
1436 struct dlm_query_join_packet packet;
1437 u32 join_resp;
1438
1439 mlog(0, "querying node %d\n", node);
1440
1441 memset(&join_msg, 0, sizeof(join_msg));
1442 join_msg.node_idx = dlm->node_num;
1443 join_msg.name_len = strlen(dlm->name);
1444 memcpy(join_msg.domain, dlm->name, join_msg.name_len);
1445 join_msg.dlm_proto = dlm->dlm_locking_proto;
1446 join_msg.fs_proto = dlm->fs_locking_proto;
1447
1448 /* copy live node map to join message */
1449 byte_copymap(join_msg.node_map, dlm->live_nodes_map, O2NM_MAX_NODES);
1450
1451 status = o2net_send_message(DLM_QUERY_JOIN_MSG, DLM_MOD_KEY, &join_msg,
1452 sizeof(join_msg), node, &join_resp);
1453 if (status < 0 && status != -ENOPROTOOPT) {
1454 mlog(ML_ERROR, "Error %d when sending message %u (key 0x%x) to "
1455 "node %u\n", status, DLM_QUERY_JOIN_MSG, DLM_MOD_KEY,
1456 node);
1457 goto bail;
1458 }
1459 dlm_query_join_wire_to_packet(join_resp, &packet);
1460
1461 /* -ENOPROTOOPT from the net code means the other side isn't
1462 listening for our message type -- that's fine, it means
1463 his dlm isn't up, so we can consider him a 'yes' but not
1464 joined into the domain. */
1465 if (status == -ENOPROTOOPT) {
1466 status = 0;
1467 *response = JOIN_OK_NO_MAP;
1468 } else {
1469 *response = packet.code;
1470 switch (packet.code) {
1471 case JOIN_DISALLOW:
1472 case JOIN_OK_NO_MAP:
1473 break;
1474 case JOIN_PROTOCOL_MISMATCH:
1475 mlog(ML_NOTICE,
1476 "This node requested DLM locking protocol %u.%u and "
1477 "filesystem locking protocol %u.%u. At least one of "
1478 "the protocol versions on node %d is not compatible, "
1479 "disconnecting\n",
1480 dlm->dlm_locking_proto.pv_major,
1481 dlm->dlm_locking_proto.pv_minor,
1482 dlm->fs_locking_proto.pv_major,
1483 dlm->fs_locking_proto.pv_minor,
1484 node);
1485 status = -EPROTO;
1486 break;
1487 case JOIN_OK:
1488 /* Use the same locking protocol as the remote node */
1489 dlm->dlm_locking_proto.pv_minor = packet.dlm_minor;
1490 dlm->fs_locking_proto.pv_minor = packet.fs_minor;
1491 mlog(0,
1492 "Node %d responds JOIN_OK with DLM locking protocol "
1493 "%u.%u and fs locking protocol %u.%u\n",
1494 node,
1495 dlm->dlm_locking_proto.pv_major,
1496 dlm->dlm_locking_proto.pv_minor,
1497 dlm->fs_locking_proto.pv_major,
1498 dlm->fs_locking_proto.pv_minor);
1499 break;
1500 default:
1501 status = -EINVAL;
1502 mlog(ML_ERROR, "invalid response %d from node %u\n",
1503 packet.code, node);
1504 /* Reset response to JOIN_DISALLOW */
1505 *response = JOIN_DISALLOW;
1506 break;
1507 }
1508 }
1509
1510 mlog(0, "status %d, node %d response is %d\n", status, node,
1511 *response);
1512
1513 bail:
1514 return status;
1515 }
1516
1517 static int dlm_send_one_join_assert(struct dlm_ctxt *dlm,
1518 unsigned int node)
1519 {
1520 int status;
1521 int ret;
1522 struct dlm_assert_joined assert_msg;
1523
1524 mlog(0, "Sending join assert to node %u\n", node);
1525
1526 memset(&assert_msg, 0, sizeof(assert_msg));
1527 assert_msg.node_idx = dlm->node_num;
1528 assert_msg.name_len = strlen(dlm->name);
1529 memcpy(assert_msg.domain, dlm->name, assert_msg.name_len);
1530
1531 status = o2net_send_message(DLM_ASSERT_JOINED_MSG, DLM_MOD_KEY,
1532 &assert_msg, sizeof(assert_msg), node,
1533 &ret);
1534 if (status < 0)
1535 mlog(ML_ERROR, "Error %d when sending message %u (key 0x%x) to "
1536 "node %u\n", status, DLM_ASSERT_JOINED_MSG, DLM_MOD_KEY,
1537 node);
1538 else
1539 status = ret;
1540
1541 return status;
1542 }
1543
1544 static void dlm_send_join_asserts(struct dlm_ctxt *dlm,
1545 unsigned long *node_map)
1546 {
1547 int status, node, live;
1548
1549 status = 0;
1550 node = -1;
1551 while ((node = find_next_bit(node_map, O2NM_MAX_NODES,
1552 node + 1)) < O2NM_MAX_NODES) {
1553 if (node == dlm->node_num)
1554 continue;
1555
1556 do {
1557 /* It is very important that this message be
1558 * received so we spin until either the node
1559 * has died or it gets the message. */
1560 status = dlm_send_one_join_assert(dlm, node);
1561
1562 spin_lock(&dlm->spinlock);
1563 live = test_bit(node, dlm->live_nodes_map);
1564 spin_unlock(&dlm->spinlock);
1565
1566 if (status) {
1567 mlog(ML_ERROR, "Error return %d asserting "
1568 "join on node %d\n", status, node);
1569
1570 /* give us some time between errors... */
1571 if (live)
1572 msleep(DLM_DOMAIN_BACKOFF_MS);
1573 }
1574 } while (status && live);
1575 }
1576 }
1577
1578 struct domain_join_ctxt {
1579 unsigned long live_map[BITS_TO_LONGS(O2NM_MAX_NODES)];
1580 unsigned long yes_resp_map[BITS_TO_LONGS(O2NM_MAX_NODES)];
1581 };
1582
1583 static int dlm_should_restart_join(struct dlm_ctxt *dlm,
1584 struct domain_join_ctxt *ctxt,
1585 enum dlm_query_join_response_code response)
1586 {
1587 int ret;
1588
1589 if (response == JOIN_DISALLOW) {
1590 mlog(0, "Latest response of disallow -- should restart\n");
1591 return 1;
1592 }
1593
1594 spin_lock(&dlm->spinlock);
1595 /* For now, we restart the process if the node maps have
1596 * changed at all */
1597 ret = memcmp(ctxt->live_map, dlm->live_nodes_map,
1598 sizeof(dlm->live_nodes_map));
1599 spin_unlock(&dlm->spinlock);
1600
1601 if (ret)
1602 mlog(0, "Node maps changed -- should restart\n");
1603
1604 return ret;
1605 }
1606
1607 static int dlm_try_to_join_domain(struct dlm_ctxt *dlm)
1608 {
1609 int status = 0, tmpstat, node;
1610 struct domain_join_ctxt *ctxt;
1611 enum dlm_query_join_response_code response = JOIN_DISALLOW;
1612
1613 mlog(0, "%p", dlm);
1614
1615 ctxt = kzalloc(sizeof(*ctxt), GFP_KERNEL);
1616 if (!ctxt) {
1617 status = -ENOMEM;
1618 mlog_errno(status);
1619 goto bail;
1620 }
1621
1622 /* group sem locking should work for us here -- we're already
1623 * registered for heartbeat events so filling this should be
1624 * atomic wrt getting those handlers called. */
1625 o2hb_fill_node_map(dlm->live_nodes_map, sizeof(dlm->live_nodes_map));
1626
1627 spin_lock(&dlm->spinlock);
1628 memcpy(ctxt->live_map, dlm->live_nodes_map, sizeof(ctxt->live_map));
1629
1630 __dlm_set_joining_node(dlm, dlm->node_num);
1631
1632 spin_unlock(&dlm->spinlock);
1633
1634 node = -1;
1635 while ((node = find_next_bit(ctxt->live_map, O2NM_MAX_NODES,
1636 node + 1)) < O2NM_MAX_NODES) {
1637 if (node == dlm->node_num)
1638 continue;
1639
1640 status = dlm_request_join(dlm, node, &response);
1641 if (status < 0) {
1642 mlog_errno(status);
1643 goto bail;
1644 }
1645
1646 /* Ok, either we got a response or the node doesn't have a
1647 * dlm up. */
1648 if (response == JOIN_OK)
1649 set_bit(node, ctxt->yes_resp_map);
1650
1651 if (dlm_should_restart_join(dlm, ctxt, response)) {
1652 status = -EAGAIN;
1653 goto bail;
1654 }
1655 }
1656
1657 mlog(0, "Yay, done querying nodes!\n");
1658
1659 /* Yay, everyone agree's we can join the domain. My domain is
1660 * comprised of all nodes who were put in the
1661 * yes_resp_map. Copy that into our domain map and send a join
1662 * assert message to clean up everyone elses state. */
1663 spin_lock(&dlm->spinlock);
1664 memcpy(dlm->domain_map, ctxt->yes_resp_map,
1665 sizeof(ctxt->yes_resp_map));
1666 set_bit(dlm->node_num, dlm->domain_map);
1667 spin_unlock(&dlm->spinlock);
1668
1669 /* Support for global heartbeat and node info was added in 1.1 */
1670 if (dlm->dlm_locking_proto.pv_major > 1 ||
1671 dlm->dlm_locking_proto.pv_minor > 0) {
1672 status = dlm_send_nodeinfo(dlm, ctxt->yes_resp_map);
1673 if (status) {
1674 mlog_errno(status);
1675 goto bail;
1676 }
1677 status = dlm_send_regions(dlm, ctxt->yes_resp_map);
1678 if (status) {
1679 mlog_errno(status);
1680 goto bail;
1681 }
1682 }
1683
1684 dlm_send_join_asserts(dlm, ctxt->yes_resp_map);
1685
1686 /* Joined state *must* be set before the joining node
1687 * information, otherwise the query_join handler may read no
1688 * current joiner but a state of NEW and tell joining nodes
1689 * we're not in the domain. */
1690 spin_lock(&dlm_domain_lock);
1691 dlm->dlm_state = DLM_CTXT_JOINED;
1692 dlm->num_joins++;
1693 spin_unlock(&dlm_domain_lock);
1694
1695 bail:
1696 spin_lock(&dlm->spinlock);
1697 __dlm_set_joining_node(dlm, DLM_LOCK_RES_OWNER_UNKNOWN);
1698 if (!status) {
1699 printk(KERN_NOTICE "o2dlm: Joining domain %s ", dlm->name);
1700 __dlm_print_nodes(dlm);
1701 }
1702 spin_unlock(&dlm->spinlock);
1703
1704 if (ctxt) {
1705 /* Do we need to send a cancel message to any nodes? */
1706 if (status < 0) {
1707 tmpstat = dlm_send_join_cancels(dlm,
1708 ctxt->yes_resp_map,
1709 sizeof(ctxt->yes_resp_map));
1710 if (tmpstat < 0)
1711 mlog_errno(tmpstat);
1712 }
1713 kfree(ctxt);
1714 }
1715
1716 mlog(0, "returning %d\n", status);
1717 return status;
1718 }
1719
1720 static void dlm_unregister_domain_handlers(struct dlm_ctxt *dlm)
1721 {
1722 o2hb_unregister_callback(dlm->name, &dlm->dlm_hb_up);
1723 o2hb_unregister_callback(dlm->name, &dlm->dlm_hb_down);
1724 o2net_unregister_handler_list(&dlm->dlm_domain_handlers);
1725 }
1726
1727 static int dlm_register_domain_handlers(struct dlm_ctxt *dlm)
1728 {
1729 int status;
1730
1731 mlog(0, "registering handlers.\n");
1732
1733 o2hb_setup_callback(&dlm->dlm_hb_down, O2HB_NODE_DOWN_CB,
1734 dlm_hb_node_down_cb, dlm, DLM_HB_NODE_DOWN_PRI);
1735 o2hb_setup_callback(&dlm->dlm_hb_up, O2HB_NODE_UP_CB,
1736 dlm_hb_node_up_cb, dlm, DLM_HB_NODE_UP_PRI);
1737
1738 status = o2hb_register_callback(dlm->name, &dlm->dlm_hb_down);
1739 if (status)
1740 goto bail;
1741
1742 status = o2hb_register_callback(dlm->name, &dlm->dlm_hb_up);
1743 if (status)
1744 goto bail;
1745
1746 status = o2net_register_handler(DLM_MASTER_REQUEST_MSG, dlm->key,
1747 sizeof(struct dlm_master_request),
1748 dlm_master_request_handler,
1749 dlm, NULL, &dlm->dlm_domain_handlers);
1750 if (status)
1751 goto bail;
1752
1753 status = o2net_register_handler(DLM_ASSERT_MASTER_MSG, dlm->key,
1754 sizeof(struct dlm_assert_master),
1755 dlm_assert_master_handler,
1756 dlm, dlm_assert_master_post_handler,
1757 &dlm->dlm_domain_handlers);
1758 if (status)
1759 goto bail;
1760
1761 status = o2net_register_handler(DLM_CREATE_LOCK_MSG, dlm->key,
1762 sizeof(struct dlm_create_lock),
1763 dlm_create_lock_handler,
1764 dlm, NULL, &dlm->dlm_domain_handlers);
1765 if (status)
1766 goto bail;
1767
1768 status = o2net_register_handler(DLM_CONVERT_LOCK_MSG, dlm->key,
1769 DLM_CONVERT_LOCK_MAX_LEN,
1770 dlm_convert_lock_handler,
1771 dlm, NULL, &dlm->dlm_domain_handlers);
1772 if (status)
1773 goto bail;
1774
1775 status = o2net_register_handler(DLM_UNLOCK_LOCK_MSG, dlm->key,
1776 DLM_UNLOCK_LOCK_MAX_LEN,
1777 dlm_unlock_lock_handler,
1778 dlm, NULL, &dlm->dlm_domain_handlers);
1779 if (status)
1780 goto bail;
1781
1782 status = o2net_register_handler(DLM_PROXY_AST_MSG, dlm->key,
1783 DLM_PROXY_AST_MAX_LEN,
1784 dlm_proxy_ast_handler,
1785 dlm, NULL, &dlm->dlm_domain_handlers);
1786 if (status)
1787 goto bail;
1788
1789 status = o2net_register_handler(DLM_EXIT_DOMAIN_MSG, dlm->key,
1790 sizeof(struct dlm_exit_domain),
1791 dlm_exit_domain_handler,
1792 dlm, NULL, &dlm->dlm_domain_handlers);
1793 if (status)
1794 goto bail;
1795
1796 status = o2net_register_handler(DLM_DEREF_LOCKRES_MSG, dlm->key,
1797 sizeof(struct dlm_deref_lockres),
1798 dlm_deref_lockres_handler,
1799 dlm, NULL, &dlm->dlm_domain_handlers);
1800 if (status)
1801 goto bail;
1802
1803 status = o2net_register_handler(DLM_MIGRATE_REQUEST_MSG, dlm->key,
1804 sizeof(struct dlm_migrate_request),
1805 dlm_migrate_request_handler,
1806 dlm, NULL, &dlm->dlm_domain_handlers);
1807 if (status)
1808 goto bail;
1809
1810 status = o2net_register_handler(DLM_MIG_LOCKRES_MSG, dlm->key,
1811 DLM_MIG_LOCKRES_MAX_LEN,
1812 dlm_mig_lockres_handler,
1813 dlm, NULL, &dlm->dlm_domain_handlers);
1814 if (status)
1815 goto bail;
1816
1817 status = o2net_register_handler(DLM_MASTER_REQUERY_MSG, dlm->key,
1818 sizeof(struct dlm_master_requery),
1819 dlm_master_requery_handler,
1820 dlm, NULL, &dlm->dlm_domain_handlers);
1821 if (status)
1822 goto bail;
1823
1824 status = o2net_register_handler(DLM_LOCK_REQUEST_MSG, dlm->key,
1825 sizeof(struct dlm_lock_request),
1826 dlm_request_all_locks_handler,
1827 dlm, NULL, &dlm->dlm_domain_handlers);
1828 if (status)
1829 goto bail;
1830
1831 status = o2net_register_handler(DLM_RECO_DATA_DONE_MSG, dlm->key,
1832 sizeof(struct dlm_reco_data_done),
1833 dlm_reco_data_done_handler,
1834 dlm, NULL, &dlm->dlm_domain_handlers);
1835 if (status)
1836 goto bail;
1837
1838 status = o2net_register_handler(DLM_BEGIN_RECO_MSG, dlm->key,
1839 sizeof(struct dlm_begin_reco),
1840 dlm_begin_reco_handler,
1841 dlm, NULL, &dlm->dlm_domain_handlers);
1842 if (status)
1843 goto bail;
1844
1845 status = o2net_register_handler(DLM_FINALIZE_RECO_MSG, dlm->key,
1846 sizeof(struct dlm_finalize_reco),
1847 dlm_finalize_reco_handler,
1848 dlm, NULL, &dlm->dlm_domain_handlers);
1849 if (status)
1850 goto bail;
1851
1852 status = o2net_register_handler(DLM_BEGIN_EXIT_DOMAIN_MSG, dlm->key,
1853 sizeof(struct dlm_exit_domain),
1854 dlm_begin_exit_domain_handler,
1855 dlm, NULL, &dlm->dlm_domain_handlers);
1856
1857 bail:
1858 if (status)
1859 dlm_unregister_domain_handlers(dlm);
1860
1861 return status;
1862 }
1863
1864 static int dlm_join_domain(struct dlm_ctxt *dlm)
1865 {
1866 int status;
1867 unsigned int backoff;
1868 unsigned int total_backoff = 0;
1869
1870 BUG_ON(!dlm);
1871
1872 mlog(0, "Join domain %s\n", dlm->name);
1873
1874 status = dlm_register_domain_handlers(dlm);
1875 if (status) {
1876 mlog_errno(status);
1877 goto bail;
1878 }
1879
1880 status = dlm_launch_thread(dlm);
1881 if (status < 0) {
1882 mlog_errno(status);
1883 goto bail;
1884 }
1885
1886 status = dlm_launch_recovery_thread(dlm);
1887 if (status < 0) {
1888 mlog_errno(status);
1889 goto bail;
1890 }
1891
1892 status = dlm_debug_init(dlm);
1893 if (status < 0) {
1894 mlog_errno(status);
1895 goto bail;
1896 }
1897
1898 dlm->dlm_worker = create_singlethread_workqueue("dlm_wq");
1899 if (!dlm->dlm_worker) {
1900 status = -ENOMEM;
1901 mlog_errno(status);
1902 goto bail;
1903 }
1904
1905 do {
1906 status = dlm_try_to_join_domain(dlm);
1907
1908 /* If we're racing another node to the join, then we
1909 * need to back off temporarily and let them
1910 * complete. */
1911 #define DLM_JOIN_TIMEOUT_MSECS 90000
1912 if (status == -EAGAIN) {
1913 if (signal_pending(current)) {
1914 status = -ERESTARTSYS;
1915 goto bail;
1916 }
1917
1918 if (total_backoff > DLM_JOIN_TIMEOUT_MSECS) {
1919 status = -ERESTARTSYS;
1920 mlog(ML_NOTICE, "Timed out joining dlm domain "
1921 "%s after %u msecs\n", dlm->name,
1922 total_backoff);
1923 goto bail;
1924 }
1925
1926 /*
1927 * <chip> After you!
1928 * <dale> No, after you!
1929 * <chip> I insist!
1930 * <dale> But you first!
1931 * ...
1932 */
1933 backoff = (unsigned int)(jiffies & 0x3);
1934 backoff *= DLM_DOMAIN_BACKOFF_MS;
1935 total_backoff += backoff;
1936 mlog(0, "backoff %d\n", backoff);
1937 msleep(backoff);
1938 }
1939 } while (status == -EAGAIN);
1940
1941 if (status < 0) {
1942 mlog_errno(status);
1943 goto bail;
1944 }
1945
1946 status = 0;
1947 bail:
1948 wake_up(&dlm_domain_events);
1949
1950 if (status) {
1951 dlm_unregister_domain_handlers(dlm);
1952 dlm_debug_shutdown(dlm);
1953 dlm_complete_thread(dlm);
1954 dlm_complete_recovery_thread(dlm);
1955 dlm_destroy_dlm_worker(dlm);
1956 }
1957
1958 return status;
1959 }
1960
1961 static struct dlm_ctxt *dlm_alloc_ctxt(const char *domain,
1962 u32 key)
1963 {
1964 int i;
1965 int ret;
1966 struct dlm_ctxt *dlm = NULL;
1967
1968 dlm = kzalloc(sizeof(*dlm), GFP_KERNEL);
1969 if (!dlm) {
1970 ret = -ENOMEM;
1971 mlog_errno(ret);
1972 goto leave;
1973 }
1974
1975 dlm->name = kstrdup(domain, GFP_KERNEL);
1976 if (dlm->name == NULL) {
1977 ret = -ENOMEM;
1978 mlog_errno(ret);
1979 goto leave;
1980 }
1981
1982 dlm->lockres_hash = (struct hlist_head **)dlm_alloc_pagevec(DLM_HASH_PAGES);
1983 if (!dlm->lockres_hash) {
1984 ret = -ENOMEM;
1985 mlog_errno(ret);
1986 goto leave;
1987 }
1988
1989 for (i = 0; i < DLM_HASH_BUCKETS; i++)
1990 INIT_HLIST_HEAD(dlm_lockres_hash(dlm, i));
1991
1992 dlm->master_hash = (struct hlist_head **)
1993 dlm_alloc_pagevec(DLM_HASH_PAGES);
1994 if (!dlm->master_hash) {
1995 ret = -ENOMEM;
1996 mlog_errno(ret);
1997 goto leave;
1998 }
1999
2000 for (i = 0; i < DLM_HASH_BUCKETS; i++)
2001 INIT_HLIST_HEAD(dlm_master_hash(dlm, i));
2002
2003 dlm->key = key;
2004 dlm->node_num = o2nm_this_node();
2005
2006 ret = dlm_create_debugfs_subroot(dlm);
2007 if (ret < 0)
2008 goto leave;
2009
2010 spin_lock_init(&dlm->spinlock);
2011 spin_lock_init(&dlm->master_lock);
2012 spin_lock_init(&dlm->ast_lock);
2013 spin_lock_init(&dlm->track_lock);
2014 INIT_LIST_HEAD(&dlm->list);
2015 INIT_LIST_HEAD(&dlm->dirty_list);
2016 INIT_LIST_HEAD(&dlm->reco.resources);
2017 INIT_LIST_HEAD(&dlm->reco.node_data);
2018 INIT_LIST_HEAD(&dlm->purge_list);
2019 INIT_LIST_HEAD(&dlm->dlm_domain_handlers);
2020 INIT_LIST_HEAD(&dlm->tracking_list);
2021 dlm->reco.state = 0;
2022
2023 INIT_LIST_HEAD(&dlm->pending_asts);
2024 INIT_LIST_HEAD(&dlm->pending_basts);
2025
2026 mlog(0, "dlm->recovery_map=%p, &(dlm->recovery_map[0])=%p\n",
2027 dlm->recovery_map, &(dlm->recovery_map[0]));
2028
2029 memset(dlm->recovery_map, 0, sizeof(dlm->recovery_map));
2030 memset(dlm->live_nodes_map, 0, sizeof(dlm->live_nodes_map));
2031 memset(dlm->domain_map, 0, sizeof(dlm->domain_map));
2032
2033 dlm->dlm_thread_task = NULL;
2034 dlm->dlm_reco_thread_task = NULL;
2035 dlm->dlm_worker = NULL;
2036 init_waitqueue_head(&dlm->dlm_thread_wq);
2037 init_waitqueue_head(&dlm->dlm_reco_thread_wq);
2038 init_waitqueue_head(&dlm->reco.event);
2039 init_waitqueue_head(&dlm->ast_wq);
2040 init_waitqueue_head(&dlm->migration_wq);
2041 INIT_LIST_HEAD(&dlm->mle_hb_events);
2042
2043 dlm->joining_node = DLM_LOCK_RES_OWNER_UNKNOWN;
2044 init_waitqueue_head(&dlm->dlm_join_events);
2045
2046 dlm->reco.new_master = O2NM_INVALID_NODE_NUM;
2047 dlm->reco.dead_node = O2NM_INVALID_NODE_NUM;
2048
2049 atomic_set(&dlm->res_tot_count, 0);
2050 atomic_set(&dlm->res_cur_count, 0);
2051 for (i = 0; i < DLM_MLE_NUM_TYPES; ++i) {
2052 atomic_set(&dlm->mle_tot_count[i], 0);
2053 atomic_set(&dlm->mle_cur_count[i], 0);
2054 }
2055
2056 spin_lock_init(&dlm->work_lock);
2057 INIT_LIST_HEAD(&dlm->work_list);
2058 INIT_WORK(&dlm->dispatched_work, dlm_dispatch_work);
2059
2060 kref_init(&dlm->dlm_refs);
2061 dlm->dlm_state = DLM_CTXT_NEW;
2062
2063 INIT_LIST_HEAD(&dlm->dlm_eviction_callbacks);
2064
2065 mlog(0, "context init: refcount %u\n",
2066 atomic_read(&dlm->dlm_refs.refcount));
2067
2068 leave:
2069 if (ret < 0 && dlm) {
2070 if (dlm->master_hash)
2071 dlm_free_pagevec((void **)dlm->master_hash,
2072 DLM_HASH_PAGES);
2073
2074 if (dlm->lockres_hash)
2075 dlm_free_pagevec((void **)dlm->lockres_hash,
2076 DLM_HASH_PAGES);
2077
2078 kfree(dlm->name);
2079 kfree(dlm);
2080 dlm = NULL;
2081 }
2082 return dlm;
2083 }
2084
2085 /*
2086 * Compare a requested locking protocol version against the current one.
2087 *
2088 * If the major numbers are different, they are incompatible.
2089 * If the current minor is greater than the request, they are incompatible.
2090 * If the current minor is less than or equal to the request, they are
2091 * compatible, and the requester should run at the current minor version.
2092 */
2093 static int dlm_protocol_compare(struct dlm_protocol_version *existing,
2094 struct dlm_protocol_version *request)
2095 {
2096 if (existing->pv_major != request->pv_major)
2097 return 1;
2098
2099 if (existing->pv_minor > request->pv_minor)
2100 return 1;
2101
2102 if (existing->pv_minor < request->pv_minor)
2103 request->pv_minor = existing->pv_minor;
2104
2105 return 0;
2106 }
2107
2108 /*
2109 * dlm_register_domain: one-time setup per "domain".
2110 *
2111 * The filesystem passes in the requested locking version via proto.
2112 * If registration was successful, proto will contain the negotiated
2113 * locking protocol.
2114 */
2115 struct dlm_ctxt * dlm_register_domain(const char *domain,
2116 u32 key,
2117 struct dlm_protocol_version *fs_proto)
2118 {
2119 int ret;
2120 struct dlm_ctxt *dlm = NULL;
2121 struct dlm_ctxt *new_ctxt = NULL;
2122
2123 if (strlen(domain) >= O2NM_MAX_NAME_LEN) {
2124 ret = -ENAMETOOLONG;
2125 mlog(ML_ERROR, "domain name length too long\n");
2126 goto leave;
2127 }
2128
2129 mlog(0, "register called for domain \"%s\"\n", domain);
2130
2131 retry:
2132 dlm = NULL;
2133 if (signal_pending(current)) {
2134 ret = -ERESTARTSYS;
2135 mlog_errno(ret);
2136 goto leave;
2137 }
2138
2139 spin_lock(&dlm_domain_lock);
2140
2141 dlm = __dlm_lookup_domain(domain);
2142 if (dlm) {
2143 if (dlm->dlm_state != DLM_CTXT_JOINED) {
2144 spin_unlock(&dlm_domain_lock);
2145
2146 mlog(0, "This ctxt is not joined yet!\n");
2147 wait_event_interruptible(dlm_domain_events,
2148 dlm_wait_on_domain_helper(
2149 domain));
2150 goto retry;
2151 }
2152
2153 if (dlm_protocol_compare(&dlm->fs_locking_proto, fs_proto)) {
2154 spin_unlock(&dlm_domain_lock);
2155 mlog(ML_ERROR,
2156 "Requested locking protocol version is not "
2157 "compatible with already registered domain "
2158 "\"%s\"\n", domain);
2159 ret = -EPROTO;
2160 goto leave;
2161 }
2162
2163 __dlm_get(dlm);
2164 dlm->num_joins++;
2165
2166 spin_unlock(&dlm_domain_lock);
2167
2168 ret = 0;
2169 goto leave;
2170 }
2171
2172 /* doesn't exist */
2173 if (!new_ctxt) {
2174 spin_unlock(&dlm_domain_lock);
2175
2176 new_ctxt = dlm_alloc_ctxt(domain, key);
2177 if (new_ctxt)
2178 goto retry;
2179
2180 ret = -ENOMEM;
2181 mlog_errno(ret);
2182 goto leave;
2183 }
2184
2185 /* a little variable switch-a-roo here... */
2186 dlm = new_ctxt;
2187 new_ctxt = NULL;
2188
2189 /* add the new domain */
2190 list_add_tail(&dlm->list, &dlm_domains);
2191 spin_unlock(&dlm_domain_lock);
2192
2193 /*
2194 * Pass the locking protocol version into the join. If the join
2195 * succeeds, it will have the negotiated protocol set.
2196 */
2197 dlm->dlm_locking_proto = dlm_protocol;
2198 dlm->fs_locking_proto = *fs_proto;
2199
2200 ret = dlm_join_domain(dlm);
2201 if (ret) {
2202 mlog_errno(ret);
2203 dlm_put(dlm);
2204 goto leave;
2205 }
2206
2207 /* Tell the caller what locking protocol we negotiated */
2208 *fs_proto = dlm->fs_locking_proto;
2209
2210 ret = 0;
2211 leave:
2212 if (new_ctxt)
2213 dlm_free_ctxt_mem(new_ctxt);
2214
2215 if (ret < 0)
2216 dlm = ERR_PTR(ret);
2217
2218 return dlm;
2219 }
2220 EXPORT_SYMBOL_GPL(dlm_register_domain);
2221
2222 static LIST_HEAD(dlm_join_handlers);
2223
2224 static void dlm_unregister_net_handlers(void)
2225 {
2226 o2net_unregister_handler_list(&dlm_join_handlers);
2227 }
2228
2229 static int dlm_register_net_handlers(void)
2230 {
2231 int status = 0;
2232
2233 status = o2net_register_handler(DLM_QUERY_JOIN_MSG, DLM_MOD_KEY,
2234 sizeof(struct dlm_query_join_request),
2235 dlm_query_join_handler,
2236 NULL, NULL, &dlm_join_handlers);
2237 if (status)
2238 goto bail;
2239
2240 status = o2net_register_handler(DLM_ASSERT_JOINED_MSG, DLM_MOD_KEY,
2241 sizeof(struct dlm_assert_joined),
2242 dlm_assert_joined_handler,
2243 NULL, NULL, &dlm_join_handlers);
2244 if (status)
2245 goto bail;
2246
2247 status = o2net_register_handler(DLM_CANCEL_JOIN_MSG, DLM_MOD_KEY,
2248 sizeof(struct dlm_cancel_join),
2249 dlm_cancel_join_handler,
2250 NULL, NULL, &dlm_join_handlers);
2251 if (status)
2252 goto bail;
2253
2254 status = o2net_register_handler(DLM_QUERY_REGION, DLM_MOD_KEY,
2255 sizeof(struct dlm_query_region),
2256 dlm_query_region_handler,
2257 NULL, NULL, &dlm_join_handlers);
2258
2259 if (status)
2260 goto bail;
2261
2262 status = o2net_register_handler(DLM_QUERY_NODEINFO, DLM_MOD_KEY,
2263 sizeof(struct dlm_query_nodeinfo),
2264 dlm_query_nodeinfo_handler,
2265 NULL, NULL, &dlm_join_handlers);
2266 bail:
2267 if (status < 0)
2268 dlm_unregister_net_handlers();
2269
2270 return status;
2271 }
2272
2273 /* Domain eviction callback handling.
2274 *
2275 * The file system requires notification of node death *before* the
2276 * dlm completes it's recovery work, otherwise it may be able to
2277 * acquire locks on resources requiring recovery. Since the dlm can
2278 * evict a node from it's domain *before* heartbeat fires, a similar
2279 * mechanism is required. */
2280
2281 /* Eviction is not expected to happen often, so a per-domain lock is
2282 * not necessary. Eviction callbacks are allowed to sleep for short
2283 * periods of time. */
2284 static DECLARE_RWSEM(dlm_callback_sem);
2285
2286 void dlm_fire_domain_eviction_callbacks(struct dlm_ctxt *dlm,
2287 int node_num)
2288 {
2289 struct dlm_eviction_cb *cb;
2290
2291 down_read(&dlm_callback_sem);
2292 list_for_each_entry(cb, &dlm->dlm_eviction_callbacks, ec_item) {
2293 cb->ec_func(node_num, cb->ec_data);
2294 }
2295 up_read(&dlm_callback_sem);
2296 }
2297
2298 void dlm_setup_eviction_cb(struct dlm_eviction_cb *cb,
2299 dlm_eviction_func *f,
2300 void *data)
2301 {
2302 INIT_LIST_HEAD(&cb->ec_item);
2303 cb->ec_func = f;
2304 cb->ec_data = data;
2305 }
2306 EXPORT_SYMBOL_GPL(dlm_setup_eviction_cb);
2307
2308 void dlm_register_eviction_cb(struct dlm_ctxt *dlm,
2309 struct dlm_eviction_cb *cb)
2310 {
2311 down_write(&dlm_callback_sem);
2312 list_add_tail(&cb->ec_item, &dlm->dlm_eviction_callbacks);
2313 up_write(&dlm_callback_sem);
2314 }
2315 EXPORT_SYMBOL_GPL(dlm_register_eviction_cb);
2316
2317 void dlm_unregister_eviction_cb(struct dlm_eviction_cb *cb)
2318 {
2319 down_write(&dlm_callback_sem);
2320 list_del_init(&cb->ec_item);
2321 up_write(&dlm_callback_sem);
2322 }
2323 EXPORT_SYMBOL_GPL(dlm_unregister_eviction_cb);
2324
2325 static int __init dlm_init(void)
2326 {
2327 int status;
2328
2329 status = dlm_init_mle_cache();
2330 if (status) {
2331 mlog(ML_ERROR, "Could not create o2dlm_mle slabcache\n");
2332 goto error;
2333 }
2334
2335 status = dlm_init_master_caches();
2336 if (status) {
2337 mlog(ML_ERROR, "Could not create o2dlm_lockres and "
2338 "o2dlm_lockname slabcaches\n");
2339 goto error;
2340 }
2341
2342 status = dlm_init_lock_cache();
2343 if (status) {
2344 mlog(ML_ERROR, "Count not create o2dlm_lock slabcache\n");
2345 goto error;
2346 }
2347
2348 status = dlm_register_net_handlers();
2349 if (status) {
2350 mlog(ML_ERROR, "Unable to register network handlers\n");
2351 goto error;
2352 }
2353
2354 status = dlm_create_debugfs_root();
2355 if (status)
2356 goto error;
2357
2358 return 0;
2359 error:
2360 dlm_unregister_net_handlers();
2361 dlm_destroy_lock_cache();
2362 dlm_destroy_master_caches();
2363 dlm_destroy_mle_cache();
2364 return -1;
2365 }
2366
2367 static void __exit dlm_exit (void)
2368 {
2369 dlm_destroy_debugfs_root();
2370 dlm_unregister_net_handlers();
2371 dlm_destroy_lock_cache();
2372 dlm_destroy_master_caches();
2373 dlm_destroy_mle_cache();
2374 }
2375
2376 MODULE_AUTHOR("Oracle");
2377 MODULE_LICENSE("GPL");
2378 MODULE_DESCRIPTION("OCFS2 Distributed Lock Management");
2379
2380 module_init(dlm_init);
2381 module_exit(dlm_exit);
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