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Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm
[linux-stable.git] / fs / ocfs2 / dlm / dlmdomain.c
blob2018501b2249373fc8ecb7070b82164dc9c036e1
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3 * dlmdomain.c
4 *
5 * defines domain join / leave apis
6 *
7 * Copyright (C) 2004 Oracle. All rights reserved.
8 */
9
10 #include <linux/module.h>
11 #include <linux/types.h>
12 #include <linux/slab.h>
13 #include <linux/highmem.h>
14 #include <linux/init.h>
15 #include <linux/spinlock.h>
16 #include <linux/delay.h>
17 #include <linux/err.h>
18 #include <linux/debugfs.h>
19 #include <linux/sched/signal.h>
20
21 #include "../cluster/heartbeat.h"
22 #include "../cluster/nodemanager.h"
23 #include "../cluster/tcp.h"
24
25 #include "dlmapi.h"
26 #include "dlmcommon.h"
27 #include "dlmdomain.h"
28 #include "dlmdebug.h"
29
30 #define MLOG_MASK_PREFIX (ML_DLM|ML_DLM_DOMAIN)
31 #include "../cluster/masklog.h"
32
33 /*
34 * ocfs2 node maps are array of long int, which limits to send them freely
35 * across the wire due to endianness issues. To workaround this, we convert
36 * long ints to byte arrays. Following 3 routines are helper functions to
37 * set/test/copy bits within those array of bytes
38 */
39 static inline void byte_set_bit(u8 nr, u8 map[])
40 {
41 map[nr >> 3] |= (1UL << (nr & 7));
42 }
43
44 static inline int byte_test_bit(u8 nr, u8 map[])
45 {
46 return ((1UL << (nr & 7)) & (map[nr >> 3])) != 0;
47 }
48
49 static inline void byte_copymap(u8 dmap[], unsigned long smap[],
50 unsigned int sz)
51 {
52 unsigned int nn;
53
54 if (!sz)
55 return;
56
57 memset(dmap, 0, ((sz + 7) >> 3));
58 for (nn = 0 ; nn < sz; nn++)
59 if (test_bit(nn, smap))
60 byte_set_bit(nn, dmap);
61 }
62
63 static void dlm_free_pagevec(void **vec, int pages)
64 {
65 while (pages--)
66 free_page((unsigned long)vec[pages]);
67 kfree(vec);
68 }
69
70 static void **dlm_alloc_pagevec(int pages)
71 {
72 void **vec = kmalloc_array(pages, sizeof(void *), GFP_KERNEL);
73 int i;
74
75 if (!vec)
76 return NULL;
77
78 for (i = 0; i < pages; i++)
79 if (!(vec[i] = (void *)__get_free_page(GFP_KERNEL)))
80 goto out_free;
81
82 mlog(0, "Allocated DLM hash pagevec; %d pages (%lu expected), %lu buckets per page\n",
83 pages, (unsigned long)DLM_HASH_PAGES,
84 (unsigned long)DLM_BUCKETS_PER_PAGE);
85 return vec;
86 out_free:
87 dlm_free_pagevec(vec, i);
88 return NULL;
89 }
90
91 /*
92 *
93 * spinlock lock ordering: if multiple locks are needed, obey this ordering:
94 * dlm_domain_lock
95 * struct dlm_ctxt->spinlock
96 * struct dlm_lock_resource->spinlock
97 * struct dlm_ctxt->master_lock
98 * struct dlm_ctxt->ast_lock
99 * dlm_master_list_entry->spinlock
100 * dlm_lock->spinlock
101 *
102 */
103
104 DEFINE_SPINLOCK(dlm_domain_lock);
105 LIST_HEAD(dlm_domains);
106 static DECLARE_WAIT_QUEUE_HEAD(dlm_domain_events);
107
108 /*
109 * The supported protocol version for DLM communication. Running domains
110 * will have a negotiated version with the same major number and a minor
111 * number equal or smaller. The dlm_ctxt->dlm_locking_proto field should
112 * be used to determine what a running domain is actually using.
113 *
114 * New in version 1.1:
115 * - Message DLM_QUERY_REGION added to support global heartbeat
116 * - Message DLM_QUERY_NODEINFO added to allow online node removes
117 * New in version 1.2:
118 * - Message DLM_BEGIN_EXIT_DOMAIN_MSG added to mark start of exit domain
119 * New in version 1.3:
120 * - Message DLM_DEREF_LOCKRES_DONE added to inform non-master that the
121 * refmap is cleared
122 */
123 static const struct dlm_protocol_version dlm_protocol = {
124 .pv_major = 1,
125 .pv_minor = 3,
126 };
127
128 #define DLM_DOMAIN_BACKOFF_MS 200
129
130 static int dlm_query_join_handler(struct o2net_msg *msg, u32 len, void *data,
131 void **ret_data);
132 static int dlm_assert_joined_handler(struct o2net_msg *msg, u32 len, void *data,
133 void **ret_data);
134 static int dlm_cancel_join_handler(struct o2net_msg *msg, u32 len, void *data,
135 void **ret_data);
136 static int dlm_query_region_handler(struct o2net_msg *msg, u32 len,
137 void *data, void **ret_data);
138 static int dlm_exit_domain_handler(struct o2net_msg *msg, u32 len, void *data,
139 void **ret_data);
140 static int dlm_protocol_compare(struct dlm_protocol_version *existing,
141 struct dlm_protocol_version *request);
142
143 static void dlm_unregister_domain_handlers(struct dlm_ctxt *dlm);
144
145 void __dlm_unhash_lockres(struct dlm_ctxt *dlm, struct dlm_lock_resource *res)
146 {
147 if (hlist_unhashed(&res->hash_node))
148 return;
149
150 mlog(0, "%s: Unhash res %.*s\n", dlm->name, res->lockname.len,
151 res->lockname.name);
152 hlist_del_init(&res->hash_node);
153 dlm_lockres_put(res);
154 }
155
156 void __dlm_insert_lockres(struct dlm_ctxt *dlm, struct dlm_lock_resource *res)
157 {
158 struct hlist_head *bucket;
159
160 assert_spin_locked(&dlm->spinlock);
161
162 bucket = dlm_lockres_hash(dlm, res->lockname.hash);
163
164 /* get a reference for our hashtable */
165 dlm_lockres_get(res);
166
167 hlist_add_head(&res->hash_node, bucket);
168
169 mlog(0, "%s: Hash res %.*s\n", dlm->name, res->lockname.len,
170 res->lockname.name);
171 }
172
173 struct dlm_lock_resource * __dlm_lookup_lockres_full(struct dlm_ctxt *dlm,
174 const char *name,
175 unsigned int len,
176 unsigned int hash)
177 {
178 struct hlist_head *bucket;
179 struct dlm_lock_resource *res;
180
181 mlog(0, "%.*s\n", len, name);
182
183 assert_spin_locked(&dlm->spinlock);
184
185 bucket = dlm_lockres_hash(dlm, hash);
186
187 hlist_for_each_entry(res, bucket, hash_node) {
188 if (res->lockname.name[0] != name[0])
189 continue;
190 if (unlikely(res->lockname.len != len))
191 continue;
192 if (memcmp(res->lockname.name + 1, name + 1, len - 1))
193 continue;
194 dlm_lockres_get(res);
195 return res;
196 }
197 return NULL;
198 }
199
200 /* intended to be called by functions which do not care about lock
201 * resources which are being purged (most net _handler functions).
202 * this will return NULL for any lock resource which is found but
203 * currently in the process of dropping its mastery reference.
204 * use __dlm_lookup_lockres_full when you need the lock resource
205 * regardless (e.g. dlm_get_lock_resource) */
206 struct dlm_lock_resource * __dlm_lookup_lockres(struct dlm_ctxt *dlm,
207 const char *name,
208 unsigned int len,
209 unsigned int hash)
210 {
211 struct dlm_lock_resource *res = NULL;
212
213 mlog(0, "%.*s\n", len, name);
214
215 assert_spin_locked(&dlm->spinlock);
216
217 res = __dlm_lookup_lockres_full(dlm, name, len, hash);
218 if (res) {
219 spin_lock(&res->spinlock);
220 if (res->state & DLM_LOCK_RES_DROPPING_REF) {
221 spin_unlock(&res->spinlock);
222 dlm_lockres_put(res);
223 return NULL;
224 }
225 spin_unlock(&res->spinlock);
226 }
227
228 return res;
229 }
230
231 struct dlm_lock_resource * dlm_lookup_lockres(struct dlm_ctxt *dlm,
232 const char *name,
233 unsigned int len)
234 {
235 struct dlm_lock_resource *res;
236 unsigned int hash = dlm_lockid_hash(name, len);
237
238 spin_lock(&dlm->spinlock);
239 res = __dlm_lookup_lockres(dlm, name, len, hash);
240 spin_unlock(&dlm->spinlock);
241 return res;
242 }
243
244 static struct dlm_ctxt * __dlm_lookup_domain_full(const char *domain, int len)
245 {
246 struct dlm_ctxt *tmp;
247
248 assert_spin_locked(&dlm_domain_lock);
249
250 /* tmp->name here is always NULL terminated,
251 * but domain may not be! */
252 list_for_each_entry(tmp, &dlm_domains, list) {
253 if (strlen(tmp->name) == len &&
254 memcmp(tmp->name, domain, len)==0)
255 return tmp;
256 }
257
258 return NULL;
259 }
260
261 /* For null terminated domain strings ONLY */
262 static struct dlm_ctxt * __dlm_lookup_domain(const char *domain)
263 {
264 assert_spin_locked(&dlm_domain_lock);
265
266 return __dlm_lookup_domain_full(domain, strlen(domain));
267 }
268
269
270 /* returns true on one of two conditions:
271 * 1) the domain does not exist
272 * 2) the domain exists and it's state is "joined" */
273 static int dlm_wait_on_domain_helper(const char *domain)
274 {
275 int ret = 0;
276 struct dlm_ctxt *tmp = NULL;
277
278 spin_lock(&dlm_domain_lock);
279
280 tmp = __dlm_lookup_domain(domain);
281 if (!tmp)
282 ret = 1;
283 else if (tmp->dlm_state == DLM_CTXT_JOINED)
284 ret = 1;
285
286 spin_unlock(&dlm_domain_lock);
287 return ret;
288 }
289
290 static void dlm_free_ctxt_mem(struct dlm_ctxt *dlm)
291 {
292 dlm_destroy_debugfs_subroot(dlm);
293
294 if (dlm->lockres_hash)
295 dlm_free_pagevec((void **)dlm->lockres_hash, DLM_HASH_PAGES);
296
297 if (dlm->master_hash)
298 dlm_free_pagevec((void **)dlm->master_hash, DLM_HASH_PAGES);
299
300 kfree(dlm->name);
301 kfree(dlm);
302 }
303
304 /* A little strange - this function will be called while holding
305 * dlm_domain_lock and is expected to be holding it on the way out. We
306 * will however drop and reacquire it multiple times */
307 static void dlm_ctxt_release(struct kref *kref)
308 {
309 struct dlm_ctxt *dlm;
310
311 dlm = container_of(kref, struct dlm_ctxt, dlm_refs);
312
313 BUG_ON(dlm->num_joins);
314 BUG_ON(dlm->dlm_state == DLM_CTXT_JOINED);
315
316 /* we may still be in the list if we hit an error during join. */
317 list_del_init(&dlm->list);
318
319 spin_unlock(&dlm_domain_lock);
320
321 mlog(0, "freeing memory from domain %s\n", dlm->name);
322
323 wake_up(&dlm_domain_events);
324
325 dlm_free_ctxt_mem(dlm);
326
327 spin_lock(&dlm_domain_lock);
328 }
329
330 void dlm_put(struct dlm_ctxt *dlm)
331 {
332 spin_lock(&dlm_domain_lock);
333 kref_put(&dlm->dlm_refs, dlm_ctxt_release);
334 spin_unlock(&dlm_domain_lock);
335 }
336
337 static void __dlm_get(struct dlm_ctxt *dlm)
338 {
339 kref_get(&dlm->dlm_refs);
340 }
341
342 /* given a questionable reference to a dlm object, gets a reference if
343 * it can find it in the list, otherwise returns NULL in which case
344 * you shouldn't trust your pointer. */
345 struct dlm_ctxt *dlm_grab(struct dlm_ctxt *dlm)
346 {
347 struct dlm_ctxt *target;
348 struct dlm_ctxt *ret = NULL;
349
350 spin_lock(&dlm_domain_lock);
351
352 list_for_each_entry(target, &dlm_domains, list) {
353 if (target == dlm) {
354 __dlm_get(target);
355 ret = target;
356 break;
357 }
358 }
359
360 spin_unlock(&dlm_domain_lock);
361
362 return ret;
363 }
364
365 int dlm_domain_fully_joined(struct dlm_ctxt *dlm)
366 {
367 int ret;
368
369 spin_lock(&dlm_domain_lock);
370 ret = (dlm->dlm_state == DLM_CTXT_JOINED) ||
371 (dlm->dlm_state == DLM_CTXT_IN_SHUTDOWN);
372 spin_unlock(&dlm_domain_lock);
373
374 return ret;
375 }
376
377 static void dlm_destroy_dlm_worker(struct dlm_ctxt *dlm)
378 {
379 if (dlm->dlm_worker) {
380 destroy_workqueue(dlm->dlm_worker);
381 dlm->dlm_worker = NULL;
382 }
383 }
384
385 static void dlm_complete_dlm_shutdown(struct dlm_ctxt *dlm)
386 {
387 dlm_unregister_domain_handlers(dlm);
388 dlm_complete_thread(dlm);
389 dlm_complete_recovery_thread(dlm);
390 dlm_destroy_dlm_worker(dlm);
391
392 /* We've left the domain. Now we can take ourselves out of the
393 * list and allow the kref stuff to help us free the
394 * memory. */
395 spin_lock(&dlm_domain_lock);
396 list_del_init(&dlm->list);
397 spin_unlock(&dlm_domain_lock);
398
399 /* Wake up anyone waiting for us to remove this domain */
400 wake_up(&dlm_domain_events);
401 }
402
403 static int dlm_migrate_all_locks(struct dlm_ctxt *dlm)
404 {
405 int i, num, n, ret = 0;
406 struct dlm_lock_resource *res;
407 struct hlist_node *iter;
408 struct hlist_head *bucket;
409 int dropped;
410
411 mlog(0, "Migrating locks from domain %s\n", dlm->name);
412
413 num = 0;
414 spin_lock(&dlm->spinlock);
415 for (i = 0; i < DLM_HASH_BUCKETS; i++) {
416 redo_bucket:
417 n = 0;
418 bucket = dlm_lockres_hash(dlm, i);
419 iter = bucket->first;
420 while (iter) {
421 n++;
422 res = hlist_entry(iter, struct dlm_lock_resource,
423 hash_node);
424 dlm_lockres_get(res);
425 /* migrate, if necessary. this will drop the dlm
426 * spinlock and retake it if it does migration. */
427 dropped = dlm_empty_lockres(dlm, res);
428
429 spin_lock(&res->spinlock);
430 if (dropped)
431 __dlm_lockres_calc_usage(dlm, res);
432 else
433 iter = res->hash_node.next;
434 spin_unlock(&res->spinlock);
435
436 dlm_lockres_put(res);
437
438 if (dropped) {
439 cond_resched_lock(&dlm->spinlock);
440 goto redo_bucket;
441 }
442 }
443 cond_resched_lock(&dlm->spinlock);
444 num += n;
445 }
446
447 if (!num) {
448 if (dlm->reco.state & DLM_RECO_STATE_ACTIVE) {
449 mlog(0, "%s: perhaps there are more lock resources "
450 "need to be migrated after dlm recovery\n", dlm->name);
451 ret = -EAGAIN;
452 } else {
453 mlog(0, "%s: we won't do dlm recovery after migrating "
454 "all lock resources\n", dlm->name);
455 dlm->migrate_done = 1;
456 }
457 }
458
459 spin_unlock(&dlm->spinlock);
460 wake_up(&dlm->dlm_thread_wq);
461
462 /* let the dlm thread take care of purging, keep scanning until
463 * nothing remains in the hash */
464 if (num) {
465 mlog(0, "%s: %d lock resources in hash last pass\n",
466 dlm->name, num);
467 ret = -EAGAIN;
468 }
469 mlog(0, "DONE Migrating locks from domain %s\n", dlm->name);
470 return ret;
471 }
472
473 static int dlm_no_joining_node(struct dlm_ctxt *dlm)
474 {
475 int ret;
476
477 spin_lock(&dlm->spinlock);
478 ret = dlm->joining_node == DLM_LOCK_RES_OWNER_UNKNOWN;
479 spin_unlock(&dlm->spinlock);
480
481 return ret;
482 }
483
484 static int dlm_begin_exit_domain_handler(struct o2net_msg *msg, u32 len,
485 void *data, void **ret_data)
486 {
487 struct dlm_ctxt *dlm = data;
488 unsigned int node;
489 struct dlm_exit_domain *exit_msg = (struct dlm_exit_domain *) msg->buf;
490
491 if (!dlm_grab(dlm))
492 return 0;
493
494 node = exit_msg->node_idx;
495 mlog(0, "%s: Node %u sent a begin exit domain message\n", dlm->name, node);
496
497 spin_lock(&dlm->spinlock);
498 set_bit(node, dlm->exit_domain_map);
499 spin_unlock(&dlm->spinlock);
500
501 dlm_put(dlm);
502
503 return 0;
504 }
505
506 static void dlm_mark_domain_leaving(struct dlm_ctxt *dlm)
507 {
508 /* Yikes, a double spinlock! I need domain_lock for the dlm
509 * state and the dlm spinlock for join state... Sorry! */
510 again:
511 spin_lock(&dlm_domain_lock);
512 spin_lock(&dlm->spinlock);
513
514 if (dlm->joining_node != DLM_LOCK_RES_OWNER_UNKNOWN) {
515 mlog(0, "Node %d is joining, we wait on it.\n",
516 dlm->joining_node);
517 spin_unlock(&dlm->spinlock);
518 spin_unlock(&dlm_domain_lock);
519
520 wait_event(dlm->dlm_join_events, dlm_no_joining_node(dlm));
521 goto again;
522 }
523
524 dlm->dlm_state = DLM_CTXT_LEAVING;
525 spin_unlock(&dlm->spinlock);
526 spin_unlock(&dlm_domain_lock);
527 }
528
529 static void __dlm_print_nodes(struct dlm_ctxt *dlm)
530 {
531 int node = -1, num = 0;
532
533 assert_spin_locked(&dlm->spinlock);
534
535 printk("( ");
536 while ((node = find_next_bit(dlm->domain_map, O2NM_MAX_NODES,
537 node + 1)) < O2NM_MAX_NODES) {
538 printk("%d ", node);
539 ++num;
540 }
541 printk(") %u nodes\n", num);
542 }
543
544 static int dlm_exit_domain_handler(struct o2net_msg *msg, u32 len, void *data,
545 void **ret_data)
546 {
547 struct dlm_ctxt *dlm = data;
548 unsigned int node;
549 struct dlm_exit_domain *exit_msg = (struct dlm_exit_domain *) msg->buf;
550
551 mlog(0, "%p %u %p", msg, len, data);
552
553 if (!dlm_grab(dlm))
554 return 0;
555
556 node = exit_msg->node_idx;
557
558 spin_lock(&dlm->spinlock);
559 clear_bit(node, dlm->domain_map);
560 clear_bit(node, dlm->exit_domain_map);
561 printk(KERN_NOTICE "o2dlm: Node %u leaves domain %s ", node, dlm->name);
562 __dlm_print_nodes(dlm);
563
564 /* notify anything attached to the heartbeat events */
565 dlm_hb_event_notify_attached(dlm, node, 0);
566
567 spin_unlock(&dlm->spinlock);
568
569 dlm_put(dlm);
570
571 return 0;
572 }
573
574 static int dlm_send_one_domain_exit(struct dlm_ctxt *dlm, u32 msg_type,
575 unsigned int node)
576 {
577 int status;
578 struct dlm_exit_domain leave_msg;
579
580 mlog(0, "%s: Sending domain exit message %u to node %u\n", dlm->name,
581 msg_type, node);
582
583 memset(&leave_msg, 0, sizeof(leave_msg));
584 leave_msg.node_idx = dlm->node_num;
585
586 status = o2net_send_message(msg_type, dlm->key, &leave_msg,
587 sizeof(leave_msg), node, NULL);
588 if (status < 0)
589 mlog(ML_ERROR, "Error %d sending domain exit message %u "
590 "to node %u on domain %s\n", status, msg_type, node,
591 dlm->name);
592
593 return status;
594 }
595
596 static void dlm_begin_exit_domain(struct dlm_ctxt *dlm)
597 {
598 int node = -1;
599
600 /* Support for begin exit domain was added in 1.2 */
601 if (dlm->dlm_locking_proto.pv_major == 1 &&
602 dlm->dlm_locking_proto.pv_minor < 2)
603 return;
604
605 /*
606 * Unlike DLM_EXIT_DOMAIN_MSG, DLM_BEGIN_EXIT_DOMAIN_MSG is purely
607 * informational. Meaning if a node does not receive the message,
608 * so be it.
609 */
610 spin_lock(&dlm->spinlock);
611 while (1) {
612 node = find_next_bit(dlm->domain_map, O2NM_MAX_NODES, node + 1);
613 if (node >= O2NM_MAX_NODES)
614 break;
615 if (node == dlm->node_num)
616 continue;
617
618 spin_unlock(&dlm->spinlock);
619 dlm_send_one_domain_exit(dlm, DLM_BEGIN_EXIT_DOMAIN_MSG, node);
620 spin_lock(&dlm->spinlock);
621 }
622 spin_unlock(&dlm->spinlock);
623 }
624
625 static void dlm_leave_domain(struct dlm_ctxt *dlm)
626 {
627 int node, clear_node, status;
628
629 /* At this point we've migrated away all our locks and won't
630 * accept mastership of new ones. The dlm is responsible for
631 * almost nothing now. We make sure not to confuse any joining
632 * nodes and then commence shutdown procedure. */
633
634 spin_lock(&dlm->spinlock);
635 /* Clear ourselves from the domain map */
636 clear_bit(dlm->node_num, dlm->domain_map);
637 while ((node = find_next_bit(dlm->domain_map, O2NM_MAX_NODES,
638 0)) < O2NM_MAX_NODES) {
639 /* Drop the dlm spinlock. This is safe wrt the domain_map.
640 * -nodes cannot be added now as the
641 * query_join_handlers knows to respond with OK_NO_MAP
642 * -we catch the right network errors if a node is
643 * removed from the map while we're sending him the
644 * exit message. */
645 spin_unlock(&dlm->spinlock);
646
647 clear_node = 1;
648
649 status = dlm_send_one_domain_exit(dlm, DLM_EXIT_DOMAIN_MSG,
650 node);
651 if (status < 0 &&
652 status != -ENOPROTOOPT &&
653 status != -ENOTCONN) {
654 mlog(ML_NOTICE, "Error %d sending domain exit message "
655 "to node %d\n", status, node);
656
657 /* Not sure what to do here but lets sleep for
658 * a bit in case this was a transient
659 * error... */
660 msleep(DLM_DOMAIN_BACKOFF_MS);
661 clear_node = 0;
662 }
663
664 spin_lock(&dlm->spinlock);
665 /* If we're not clearing the node bit then we intend
666 * to loop back around to try again. */
667 if (clear_node)
668 clear_bit(node, dlm->domain_map);
669 }
670 spin_unlock(&dlm->spinlock);
671 }
672
673 void dlm_unregister_domain(struct dlm_ctxt *dlm)
674 {
675 int leave = 0;
676 struct dlm_lock_resource *res;
677
678 spin_lock(&dlm_domain_lock);
679 BUG_ON(dlm->dlm_state != DLM_CTXT_JOINED);
680 BUG_ON(!dlm->num_joins);
681
682 dlm->num_joins--;
683 if (!dlm->num_joins) {
684 /* We mark it "in shutdown" now so new register
685 * requests wait until we've completely left the
686 * domain. Don't use DLM_CTXT_LEAVING yet as we still
687 * want new domain joins to communicate with us at
688 * least until we've completed migration of our
689 * resources. */
690 dlm->dlm_state = DLM_CTXT_IN_SHUTDOWN;
691 leave = 1;
692 }
693 spin_unlock(&dlm_domain_lock);
694
695 if (leave) {
696 mlog(0, "shutting down domain %s\n", dlm->name);
697 dlm_begin_exit_domain(dlm);
698
699 /* We changed dlm state, notify the thread */
700 dlm_kick_thread(dlm, NULL);
701
702 while (dlm_migrate_all_locks(dlm)) {
703 /* Give dlm_thread time to purge the lockres' */
704 msleep(500);
705 mlog(0, "%s: more migration to do\n", dlm->name);
706 }
707
708 /* This list should be empty. If not, print remaining lockres */
709 if (!list_empty(&dlm->tracking_list)) {
710 mlog(ML_ERROR, "Following lockres' are still on the "
711 "tracking list:\n");
712 list_for_each_entry(res, &dlm->tracking_list, tracking)
713 dlm_print_one_lock_resource(res);
714 }
715
716 dlm_mark_domain_leaving(dlm);
717 dlm_leave_domain(dlm);
718 printk(KERN_NOTICE "o2dlm: Leaving domain %s\n", dlm->name);
719 dlm_force_free_mles(dlm);
720 dlm_complete_dlm_shutdown(dlm);
721 }
722 dlm_put(dlm);
723 }
724 EXPORT_SYMBOL_GPL(dlm_unregister_domain);
725
726 static int dlm_query_join_proto_check(char *proto_type, int node,
727 struct dlm_protocol_version *ours,
728 struct dlm_protocol_version *request)
729 {
730 int rc;
731 struct dlm_protocol_version proto = *request;
732
733 if (!dlm_protocol_compare(ours, &proto)) {
734 mlog(0,
735 "node %u wanted to join with %s locking protocol "
736 "%u.%u, we respond with %u.%u\n",
737 node, proto_type,
738 request->pv_major,
739 request->pv_minor,
740 proto.pv_major, proto.pv_minor);
741 request->pv_minor = proto.pv_minor;
742 rc = 0;
743 } else {
744 mlog(ML_NOTICE,
745 "Node %u wanted to join with %s locking "
746 "protocol %u.%u, but we have %u.%u, disallowing\n",
747 node, proto_type,
748 request->pv_major,
749 request->pv_minor,
750 ours->pv_major,
751 ours->pv_minor);
752 rc = 1;
753 }
754
755 return rc;
756 }
757
758 /*
759 * struct dlm_query_join_packet is made up of four one-byte fields. They
760 * are effectively in big-endian order already. However, little-endian
761 * machines swap them before putting the packet on the wire (because
762 * query_join's response is a status, and that status is treated as a u32
763 * on the wire). Thus, a big-endian and little-endian machines will treat
764 * this structure differently.
765 *
766 * The solution is to have little-endian machines swap the structure when
767 * converting from the structure to the u32 representation. This will
768 * result in the structure having the correct format on the wire no matter
769 * the host endian format.
770 */
771 static void dlm_query_join_packet_to_wire(struct dlm_query_join_packet *packet,
772 u32 *wire)
773 {
774 union dlm_query_join_response response;
775
776 response.packet = *packet;
777 *wire = be32_to_cpu(response.intval);
778 }
779
780 static void dlm_query_join_wire_to_packet(u32 wire,
781 struct dlm_query_join_packet *packet)
782 {
783 union dlm_query_join_response response;
784
785 response.intval = cpu_to_be32(wire);
786 *packet = response.packet;
787 }
788
789 static int dlm_query_join_handler(struct o2net_msg *msg, u32 len, void *data,
790 void **ret_data)
791 {
792 struct dlm_query_join_request *query;
793 struct dlm_query_join_packet packet = {
794 .code = JOIN_DISALLOW,
795 };
796 struct dlm_ctxt *dlm = NULL;
797 u32 response;
798 u8 nodenum;
799
800 query = (struct dlm_query_join_request *) msg->buf;
801
802 mlog(0, "node %u wants to join domain %s\n", query->node_idx,
803 query->domain);
804
805 /*
806 * If heartbeat doesn't consider the node live, tell it
807 * to back off and try again. This gives heartbeat a chance
808 * to catch up.
809 */
810 if (!o2hb_check_node_heartbeating_no_sem(query->node_idx)) {
811 mlog(0, "node %u is not in our live map yet\n",
812 query->node_idx);
813
814 packet.code = JOIN_DISALLOW;
815 goto respond;
816 }
817
818 packet.code = JOIN_OK_NO_MAP;
819
820 spin_lock(&dlm_domain_lock);
821 dlm = __dlm_lookup_domain_full(query->domain, query->name_len);
822 if (!dlm)
823 goto unlock_respond;
824
825 /*
826 * There is a small window where the joining node may not see the
827 * node(s) that just left but still part of the cluster. DISALLOW
828 * join request if joining node has different node map.
829 */
830 nodenum=0;
831 while (nodenum < O2NM_MAX_NODES) {
832 if (test_bit(nodenum, dlm->domain_map)) {
833 if (!byte_test_bit(nodenum, query->node_map)) {
834 mlog(0, "disallow join as node %u does not "
835 "have node %u in its nodemap\n",
836 query->node_idx, nodenum);
837 packet.code = JOIN_DISALLOW;
838 goto unlock_respond;
839 }
840 }
841 nodenum++;
842 }
843
844 /* Once the dlm ctxt is marked as leaving then we don't want
845 * to be put in someone's domain map.
846 * Also, explicitly disallow joining at certain troublesome
847 * times (ie. during recovery). */
848 if (dlm->dlm_state != DLM_CTXT_LEAVING) {
849 int bit = query->node_idx;
850 spin_lock(&dlm->spinlock);
851
852 if (dlm->dlm_state == DLM_CTXT_NEW &&
853 dlm->joining_node == DLM_LOCK_RES_OWNER_UNKNOWN) {
854 /*If this is a brand new context and we
855 * haven't started our join process yet, then
856 * the other node won the race. */
857 packet.code = JOIN_OK_NO_MAP;
858 } else if (dlm->joining_node != DLM_LOCK_RES_OWNER_UNKNOWN) {
859 /* Disallow parallel joins. */
860 packet.code = JOIN_DISALLOW;
861 } else if (dlm->reco.state & DLM_RECO_STATE_ACTIVE) {
862 mlog(0, "node %u trying to join, but recovery "
863 "is ongoing.\n", bit);
864 packet.code = JOIN_DISALLOW;
865 } else if (test_bit(bit, dlm->recovery_map)) {
866 mlog(0, "node %u trying to join, but it "
867 "still needs recovery.\n", bit);
868 packet.code = JOIN_DISALLOW;
869 } else if (test_bit(bit, dlm->domain_map)) {
870 mlog(0, "node %u trying to join, but it "
871 "is still in the domain! needs recovery?\n",
872 bit);
873 packet.code = JOIN_DISALLOW;
874 } else {
875 /* Alright we're fully a part of this domain
876 * so we keep some state as to who's joining
877 * and indicate to him that needs to be fixed
878 * up. */
879
880 /* Make sure we speak compatible locking protocols. */
881 if (dlm_query_join_proto_check("DLM", bit,
882 &dlm->dlm_locking_proto,
883 &query->dlm_proto)) {
884 packet.code = JOIN_PROTOCOL_MISMATCH;
885 } else if (dlm_query_join_proto_check("fs", bit,
886 &dlm->fs_locking_proto,
887 &query->fs_proto)) {
888 packet.code = JOIN_PROTOCOL_MISMATCH;
889 } else {
890 packet.dlm_minor = query->dlm_proto.pv_minor;
891 packet.fs_minor = query->fs_proto.pv_minor;
892 packet.code = JOIN_OK;
893 __dlm_set_joining_node(dlm, query->node_idx);
894 }
895 }
896
897 spin_unlock(&dlm->spinlock);
898 }
899 unlock_respond:
900 spin_unlock(&dlm_domain_lock);
901
902 respond:
903 mlog(0, "We respond with %u\n", packet.code);
904
905 dlm_query_join_packet_to_wire(&packet, &response);
906 return response;
907 }
908
909 static int dlm_assert_joined_handler(struct o2net_msg *msg, u32 len, void *data,
910 void **ret_data)
911 {
912 struct dlm_assert_joined *assert;
913 struct dlm_ctxt *dlm = NULL;
914
915 assert = (struct dlm_assert_joined *) msg->buf;
916
917 mlog(0, "node %u asserts join on domain %s\n", assert->node_idx,
918 assert->domain);
919
920 spin_lock(&dlm_domain_lock);
921 dlm = __dlm_lookup_domain_full(assert->domain, assert->name_len);
922 /* XXX should we consider no dlm ctxt an error? */
923 if (dlm) {
924 spin_lock(&dlm->spinlock);
925
926 /* Alright, this node has officially joined our
927 * domain. Set him in the map and clean up our
928 * leftover join state. */
929 BUG_ON(dlm->joining_node != assert->node_idx);
930
931 if (dlm->reco.state & DLM_RECO_STATE_ACTIVE) {
932 mlog(0, "dlm recovery is ongoing, disallow join\n");
933 spin_unlock(&dlm->spinlock);
934 spin_unlock(&dlm_domain_lock);
935 return -EAGAIN;
936 }
937
938 set_bit(assert->node_idx, dlm->domain_map);
939 clear_bit(assert->node_idx, dlm->exit_domain_map);
940 __dlm_set_joining_node(dlm, DLM_LOCK_RES_OWNER_UNKNOWN);
941
942 printk(KERN_NOTICE "o2dlm: Node %u joins domain %s ",
943 assert->node_idx, dlm->name);
944 __dlm_print_nodes(dlm);
945
946 /* notify anything attached to the heartbeat events */
947 dlm_hb_event_notify_attached(dlm, assert->node_idx, 1);
948
949 spin_unlock(&dlm->spinlock);
950 }
951 spin_unlock(&dlm_domain_lock);
952
953 return 0;
954 }
955
956 static int dlm_match_regions(struct dlm_ctxt *dlm,
957 struct dlm_query_region *qr,
958 char *local, int locallen)
959 {
960 char *remote = qr->qr_regions;
961 char *l, *r;
962 int localnr, i, j, foundit;
963 int status = 0;
964
965 if (!o2hb_global_heartbeat_active()) {
966 if (qr->qr_numregions) {
967 mlog(ML_ERROR, "Domain %s: Joining node %d has global "
968 "heartbeat enabled but local node %d does not\n",
969 qr->qr_domain, qr->qr_node, dlm->node_num);
970 status = -EINVAL;
971 }
972 goto bail;
973 }
974
975 if (o2hb_global_heartbeat_active() && !qr->qr_numregions) {
976 mlog(ML_ERROR, "Domain %s: Local node %d has global "
977 "heartbeat enabled but joining node %d does not\n",
978 qr->qr_domain, dlm->node_num, qr->qr_node);
979 status = -EINVAL;
980 goto bail;
981 }
982
983 r = remote;
984 for (i = 0; i < qr->qr_numregions; ++i) {
985 mlog(0, "Region %.*s\n", O2HB_MAX_REGION_NAME_LEN, r);
986 r += O2HB_MAX_REGION_NAME_LEN;
987 }
988
989 localnr = min(O2NM_MAX_REGIONS, locallen/O2HB_MAX_REGION_NAME_LEN);
990 localnr = o2hb_get_all_regions(local, (u8)localnr);
991
992 /* compare local regions with remote */
993 l = local;
994 for (i = 0; i < localnr; ++i) {
995 foundit = 0;
996 r = remote;
997 for (j = 0; j <= qr->qr_numregions; ++j) {
998 if (!memcmp(l, r, O2HB_MAX_REGION_NAME_LEN)) {
999 foundit = 1;
1000 break;
1001 }
1002 r += O2HB_MAX_REGION_NAME_LEN;
1003 }
1004 if (!foundit) {
1005 status = -EINVAL;
1006 mlog(ML_ERROR, "Domain %s: Region '%.*s' registered "
1007 "in local node %d but not in joining node %d\n",
1008 qr->qr_domain, O2HB_MAX_REGION_NAME_LEN, l,
1009 dlm->node_num, qr->qr_node);
1010 goto bail;
1011 }
1012 l += O2HB_MAX_REGION_NAME_LEN;
1013 }
1014
1015 /* compare remote with local regions */
1016 r = remote;
1017 for (i = 0; i < qr->qr_numregions; ++i) {
1018 foundit = 0;
1019 l = local;
1020 for (j = 0; j < localnr; ++j) {
1021 if (!memcmp(r, l, O2HB_MAX_REGION_NAME_LEN)) {
1022 foundit = 1;
1023 break;
1024 }
1025 l += O2HB_MAX_REGION_NAME_LEN;
1026 }
1027 if (!foundit) {
1028 status = -EINVAL;
1029 mlog(ML_ERROR, "Domain %s: Region '%.*s' registered "
1030 "in joining node %d but not in local node %d\n",
1031 qr->qr_domain, O2HB_MAX_REGION_NAME_LEN, r,
1032 qr->qr_node, dlm->node_num);
1033 goto bail;
1034 }
1035 r += O2HB_MAX_REGION_NAME_LEN;
1036 }
1037
1038 bail:
1039 return status;
1040 }
1041
1042 static int dlm_send_regions(struct dlm_ctxt *dlm, unsigned long *node_map)
1043 {
1044 struct dlm_query_region *qr = NULL;
1045 int status, ret = 0, i;
1046 char *p;
1047
1048 if (find_first_bit(node_map, O2NM_MAX_NODES) >= O2NM_MAX_NODES)
1049 goto bail;
1050
1051 qr = kzalloc(sizeof(struct dlm_query_region), GFP_KERNEL);
1052 if (!qr) {
1053 ret = -ENOMEM;
1054 mlog_errno(ret);
1055 goto bail;
1056 }
1057
1058 qr->qr_node = dlm->node_num;
1059 qr->qr_namelen = strlen(dlm->name);
1060 memcpy(qr->qr_domain, dlm->name, qr->qr_namelen);
1061 /* if local hb, the numregions will be zero */
1062 if (o2hb_global_heartbeat_active())
1063 qr->qr_numregions = o2hb_get_all_regions(qr->qr_regions,
1064 O2NM_MAX_REGIONS);
1065
1066 p = qr->qr_regions;
1067 for (i = 0; i < qr->qr_numregions; ++i, p += O2HB_MAX_REGION_NAME_LEN)
1068 mlog(0, "Region %.*s\n", O2HB_MAX_REGION_NAME_LEN, p);
1069
1070 i = -1;
1071 while ((i = find_next_bit(node_map, O2NM_MAX_NODES,
1072 i + 1)) < O2NM_MAX_NODES) {
1073 if (i == dlm->node_num)
1074 continue;
1075
1076 mlog(0, "Sending regions to node %d\n", i);
1077
1078 ret = o2net_send_message(DLM_QUERY_REGION, DLM_MOD_KEY, qr,
1079 sizeof(struct dlm_query_region),
1080 i, &status);
1081 if (ret >= 0)
1082 ret = status;
1083 if (ret) {
1084 mlog(ML_ERROR, "Region mismatch %d, node %d\n",
1085 ret, i);
1086 break;
1087 }
1088 }
1089
1090 bail:
1091 kfree(qr);
1092 return ret;
1093 }
1094
1095 static int dlm_query_region_handler(struct o2net_msg *msg, u32 len,
1096 void *data, void **ret_data)
1097 {
1098 struct dlm_query_region *qr;
1099 struct dlm_ctxt *dlm = NULL;
1100 char *local = NULL;
1101 int status = 0;
1102
1103 qr = (struct dlm_query_region *) msg->buf;
1104
1105 mlog(0, "Node %u queries hb regions on domain %s\n", qr->qr_node,
1106 qr->qr_domain);
1107
1108 /* buffer used in dlm_mast_regions() */
1109 local = kmalloc(sizeof(qr->qr_regions), GFP_KERNEL);
1110 if (!local)
1111 return -ENOMEM;
1112
1113 status = -EINVAL;
1114
1115 spin_lock(&dlm_domain_lock);
1116 dlm = __dlm_lookup_domain_full(qr->qr_domain, qr->qr_namelen);
1117 if (!dlm) {
1118 mlog(ML_ERROR, "Node %d queried hb regions on domain %s "
1119 "before join domain\n", qr->qr_node, qr->qr_domain);
1120 goto out_domain_lock;
1121 }
1122
1123 spin_lock(&dlm->spinlock);
1124 if (dlm->joining_node != qr->qr_node) {
1125 mlog(ML_ERROR, "Node %d queried hb regions on domain %s "
1126 "but joining node is %d\n", qr->qr_node, qr->qr_domain,
1127 dlm->joining_node);
1128 goto out_dlm_lock;
1129 }
1130
1131 /* Support for global heartbeat was added in 1.1 */
1132 if (dlm->dlm_locking_proto.pv_major == 1 &&
1133 dlm->dlm_locking_proto.pv_minor == 0) {
1134 mlog(ML_ERROR, "Node %d queried hb regions on domain %s "
1135 "but active dlm protocol is %d.%d\n", qr->qr_node,
1136 qr->qr_domain, dlm->dlm_locking_proto.pv_major,
1137 dlm->dlm_locking_proto.pv_minor);
1138 goto out_dlm_lock;
1139 }
1140
1141 status = dlm_match_regions(dlm, qr, local, sizeof(qr->qr_regions));
1142
1143 out_dlm_lock:
1144 spin_unlock(&dlm->spinlock);
1145
1146 out_domain_lock:
1147 spin_unlock(&dlm_domain_lock);
1148
1149 kfree(local);
1150
1151 return status;
1152 }
1153
1154 static int dlm_match_nodes(struct dlm_ctxt *dlm, struct dlm_query_nodeinfo *qn)
1155 {
1156 struct o2nm_node *local;
1157 struct dlm_node_info *remote;
1158 int i, j;
1159 int status = 0;
1160
1161 for (j = 0; j < qn->qn_numnodes; ++j)
1162 mlog(0, "Node %3d, %pI4:%u\n", qn->qn_nodes[j].ni_nodenum,
1163 &(qn->qn_nodes[j].ni_ipv4_address),
1164 ntohs(qn->qn_nodes[j].ni_ipv4_port));
1165
1166 for (i = 0; i < O2NM_MAX_NODES && !status; ++i) {
1167 local = o2nm_get_node_by_num(i);
1168 remote = NULL;
1169 for (j = 0; j < qn->qn_numnodes; ++j) {
1170 if (qn->qn_nodes[j].ni_nodenum == i) {
1171 remote = &(qn->qn_nodes[j]);
1172 break;
1173 }
1174 }
1175
1176 if (!local && !remote)
1177 continue;
1178
1179 if ((local && !remote) || (!local && remote))
1180 status = -EINVAL;
1181
1182 if (!status &&
1183 ((remote->ni_nodenum != local->nd_num) ||
1184 (remote->ni_ipv4_port != local->nd_ipv4_port) ||
1185 (remote->ni_ipv4_address != local->nd_ipv4_address)))
1186 status = -EINVAL;
1187
1188 if (status) {
1189 if (remote && !local)
1190 mlog(ML_ERROR, "Domain %s: Node %d (%pI4:%u) "
1191 "registered in joining node %d but not in "
1192 "local node %d\n", qn->qn_domain,
1193 remote->ni_nodenum,
1194 &(remote->ni_ipv4_address),
1195 ntohs(remote->ni_ipv4_port),
1196 qn->qn_nodenum, dlm->node_num);
1197 if (local && !remote)
1198 mlog(ML_ERROR, "Domain %s: Node %d (%pI4:%u) "
1199 "registered in local node %d but not in "
1200 "joining node %d\n", qn->qn_domain,
1201 local->nd_num, &(local->nd_ipv4_address),
1202 ntohs(local->nd_ipv4_port),
1203 dlm->node_num, qn->qn_nodenum);
1204 BUG_ON((!local && !remote));
1205 }
1206
1207 if (local)
1208 o2nm_node_put(local);
1209 }
1210
1211 return status;
1212 }
1213
1214 static int dlm_send_nodeinfo(struct dlm_ctxt *dlm, unsigned long *node_map)
1215 {
1216 struct dlm_query_nodeinfo *qn = NULL;
1217 struct o2nm_node *node;
1218 int ret = 0, status, count, i;
1219
1220 if (find_first_bit(node_map, O2NM_MAX_NODES) >= O2NM_MAX_NODES)
1221 goto bail;
1222
1223 qn = kzalloc(sizeof(struct dlm_query_nodeinfo), GFP_KERNEL);
1224 if (!qn) {
1225 ret = -ENOMEM;
1226 mlog_errno(ret);
1227 goto bail;
1228 }
1229
1230 for (i = 0, count = 0; i < O2NM_MAX_NODES; ++i) {
1231 node = o2nm_get_node_by_num(i);
1232 if (!node)
1233 continue;
1234 qn->qn_nodes[count].ni_nodenum = node->nd_num;
1235 qn->qn_nodes[count].ni_ipv4_port = node->nd_ipv4_port;
1236 qn->qn_nodes[count].ni_ipv4_address = node->nd_ipv4_address;
1237 mlog(0, "Node %3d, %pI4:%u\n", node->nd_num,
1238 &(node->nd_ipv4_address), ntohs(node->nd_ipv4_port));
1239 ++count;
1240 o2nm_node_put(node);
1241 }
1242
1243 qn->qn_nodenum = dlm->node_num;
1244 qn->qn_numnodes = count;
1245 qn->qn_namelen = strlen(dlm->name);
1246 memcpy(qn->qn_domain, dlm->name, qn->qn_namelen);
1247
1248 i = -1;
1249 while ((i = find_next_bit(node_map, O2NM_MAX_NODES,
1250 i + 1)) < O2NM_MAX_NODES) {
1251 if (i == dlm->node_num)
1252 continue;
1253
1254 mlog(0, "Sending nodeinfo to node %d\n", i);
1255
1256 ret = o2net_send_message(DLM_QUERY_NODEINFO, DLM_MOD_KEY,
1257 qn, sizeof(struct dlm_query_nodeinfo),
1258 i, &status);
1259 if (ret >= 0)
1260 ret = status;
1261 if (ret) {
1262 mlog(ML_ERROR, "node mismatch %d, node %d\n", ret, i);
1263 break;
1264 }
1265 }
1266
1267 bail:
1268 kfree(qn);
1269 return ret;
1270 }
1271
1272 static int dlm_query_nodeinfo_handler(struct o2net_msg *msg, u32 len,
1273 void *data, void **ret_data)
1274 {
1275 struct dlm_query_nodeinfo *qn;
1276 struct dlm_ctxt *dlm = NULL;
1277 int status = -EINVAL;
1278
1279 qn = (struct dlm_query_nodeinfo *) msg->buf;
1280
1281 mlog(0, "Node %u queries nodes on domain %s\n", qn->qn_nodenum,
1282 qn->qn_domain);
1283
1284 spin_lock(&dlm_domain_lock);
1285 dlm = __dlm_lookup_domain_full(qn->qn_domain, qn->qn_namelen);
1286 if (!dlm) {
1287 mlog(ML_ERROR, "Node %d queried nodes on domain %s before "
1288 "join domain\n", qn->qn_nodenum, qn->qn_domain);
1289 goto bail;
1290 }
1291
1292 spin_lock(&dlm->spinlock);
1293 if (dlm->joining_node != qn->qn_nodenum) {
1294 mlog(ML_ERROR, "Node %d queried nodes on domain %s but "
1295 "joining node is %d\n", qn->qn_nodenum, qn->qn_domain,
1296 dlm->joining_node);
1297 goto unlock;
1298 }
1299
1300 /* Support for node query was added in 1.1 */
1301 if (dlm->dlm_locking_proto.pv_major == 1 &&
1302 dlm->dlm_locking_proto.pv_minor == 0) {
1303 mlog(ML_ERROR, "Node %d queried nodes on domain %s "
1304 "but active dlm protocol is %d.%d\n", qn->qn_nodenum,
1305 qn->qn_domain, dlm->dlm_locking_proto.pv_major,
1306 dlm->dlm_locking_proto.pv_minor);
1307 goto unlock;
1308 }
1309
1310 status = dlm_match_nodes(dlm, qn);
1311
1312 unlock:
1313 spin_unlock(&dlm->spinlock);
1314 bail:
1315 spin_unlock(&dlm_domain_lock);
1316
1317 return status;
1318 }
1319
1320 static int dlm_cancel_join_handler(struct o2net_msg *msg, u32 len, void *data,
1321 void **ret_data)
1322 {
1323 struct dlm_cancel_join *cancel;
1324 struct dlm_ctxt *dlm = NULL;
1325
1326 cancel = (struct dlm_cancel_join *) msg->buf;
1327
1328 mlog(0, "node %u cancels join on domain %s\n", cancel->node_idx,
1329 cancel->domain);
1330
1331 spin_lock(&dlm_domain_lock);
1332 dlm = __dlm_lookup_domain_full(cancel->domain, cancel->name_len);
1333
1334 if (dlm) {
1335 spin_lock(&dlm->spinlock);
1336
1337 /* Yikes, this guy wants to cancel his join. No
1338 * problem, we simply cleanup our join state. */
1339 BUG_ON(dlm->joining_node != cancel->node_idx);
1340 __dlm_set_joining_node(dlm, DLM_LOCK_RES_OWNER_UNKNOWN);
1341
1342 spin_unlock(&dlm->spinlock);
1343 }
1344 spin_unlock(&dlm_domain_lock);
1345
1346 return 0;
1347 }
1348
1349 static int dlm_send_one_join_cancel(struct dlm_ctxt *dlm,
1350 unsigned int node)
1351 {
1352 int status;
1353 struct dlm_cancel_join cancel_msg;
1354
1355 memset(&cancel_msg, 0, sizeof(cancel_msg));
1356 cancel_msg.node_idx = dlm->node_num;
1357 cancel_msg.name_len = strlen(dlm->name);
1358 memcpy(cancel_msg.domain, dlm->name, cancel_msg.name_len);
1359
1360 status = o2net_send_message(DLM_CANCEL_JOIN_MSG, DLM_MOD_KEY,
1361 &cancel_msg, sizeof(cancel_msg), node,
1362 NULL);
1363 if (status < 0) {
1364 mlog(ML_ERROR, "Error %d when sending message %u (key 0x%x) to "
1365 "node %u\n", status, DLM_CANCEL_JOIN_MSG, DLM_MOD_KEY,
1366 node);
1367 goto bail;
1368 }
1369
1370 bail:
1371 return status;
1372 }
1373
1374 /* map_size should be in bytes. */
1375 static int dlm_send_join_cancels(struct dlm_ctxt *dlm,
1376 unsigned long *node_map,
1377 unsigned int map_size)
1378 {
1379 int status, tmpstat;
1380 int node;
1381
1382 if (map_size != (BITS_TO_LONGS(O2NM_MAX_NODES) *
1383 sizeof(unsigned long))) {
1384 mlog(ML_ERROR,
1385 "map_size %u != BITS_TO_LONGS(O2NM_MAX_NODES) %u\n",
1386 map_size, (unsigned)BITS_TO_LONGS(O2NM_MAX_NODES));
1387 return -EINVAL;
1388 }
1389
1390 status = 0;
1391 node = -1;
1392 while ((node = find_next_bit(node_map, O2NM_MAX_NODES,
1393 node + 1)) < O2NM_MAX_NODES) {
1394 if (node == dlm->node_num)
1395 continue;
1396
1397 tmpstat = dlm_send_one_join_cancel(dlm, node);
1398 if (tmpstat) {
1399 mlog(ML_ERROR, "Error return %d cancelling join on "
1400 "node %d\n", tmpstat, node);
1401 if (!status)
1402 status = tmpstat;
1403 }
1404 }
1405
1406 if (status)
1407 mlog_errno(status);
1408 return status;
1409 }
1410
1411 static int dlm_request_join(struct dlm_ctxt *dlm,
1412 int node,
1413 enum dlm_query_join_response_code *response)
1414 {
1415 int status;
1416 struct dlm_query_join_request join_msg;
1417 struct dlm_query_join_packet packet;
1418 u32 join_resp;
1419
1420 mlog(0, "querying node %d\n", node);
1421
1422 memset(&join_msg, 0, sizeof(join_msg));
1423 join_msg.node_idx = dlm->node_num;
1424 join_msg.name_len = strlen(dlm->name);
1425 memcpy(join_msg.domain, dlm->name, join_msg.name_len);
1426 join_msg.dlm_proto = dlm->dlm_locking_proto;
1427 join_msg.fs_proto = dlm->fs_locking_proto;
1428
1429 /* copy live node map to join message */
1430 byte_copymap(join_msg.node_map, dlm->live_nodes_map, O2NM_MAX_NODES);
1431
1432 status = o2net_send_message(DLM_QUERY_JOIN_MSG, DLM_MOD_KEY, &join_msg,
1433 sizeof(join_msg), node, &join_resp);
1434 if (status < 0 && status != -ENOPROTOOPT) {
1435 mlog(ML_ERROR, "Error %d when sending message %u (key 0x%x) to "
1436 "node %u\n", status, DLM_QUERY_JOIN_MSG, DLM_MOD_KEY,
1437 node);
1438 goto bail;
1439 }
1440 dlm_query_join_wire_to_packet(join_resp, &packet);
1441
1442 /* -ENOPROTOOPT from the net code means the other side isn't
1443 listening for our message type -- that's fine, it means
1444 his dlm isn't up, so we can consider him a 'yes' but not
1445 joined into the domain. */
1446 if (status == -ENOPROTOOPT) {
1447 status = 0;
1448 *response = JOIN_OK_NO_MAP;
1449 } else {
1450 *response = packet.code;
1451 switch (packet.code) {
1452 case JOIN_DISALLOW:
1453 case JOIN_OK_NO_MAP:
1454 break;
1455 case JOIN_PROTOCOL_MISMATCH:
1456 mlog(ML_NOTICE,
1457 "This node requested DLM locking protocol %u.%u and "
1458 "filesystem locking protocol %u.%u. At least one of "
1459 "the protocol versions on node %d is not compatible, "
1460 "disconnecting\n",
1461 dlm->dlm_locking_proto.pv_major,
1462 dlm->dlm_locking_proto.pv_minor,
1463 dlm->fs_locking_proto.pv_major,
1464 dlm->fs_locking_proto.pv_minor,
1465 node);
1466 status = -EPROTO;
1467 break;
1468 case JOIN_OK:
1469 /* Use the same locking protocol as the remote node */
1470 dlm->dlm_locking_proto.pv_minor = packet.dlm_minor;
1471 dlm->fs_locking_proto.pv_minor = packet.fs_minor;
1472 mlog(0,
1473 "Node %d responds JOIN_OK with DLM locking protocol "
1474 "%u.%u and fs locking protocol %u.%u\n",
1475 node,
1476 dlm->dlm_locking_proto.pv_major,
1477 dlm->dlm_locking_proto.pv_minor,
1478 dlm->fs_locking_proto.pv_major,
1479 dlm->fs_locking_proto.pv_minor);
1480 break;
1481 default:
1482 status = -EINVAL;
1483 mlog(ML_ERROR, "invalid response %d from node %u\n",
1484 packet.code, node);
1485 /* Reset response to JOIN_DISALLOW */
1486 *response = JOIN_DISALLOW;
1487 break;
1488 }
1489 }
1490
1491 mlog(0, "status %d, node %d response is %d\n", status, node,
1492 *response);
1493
1494 bail:
1495 return status;
1496 }
1497
1498 static int dlm_send_one_join_assert(struct dlm_ctxt *dlm,
1499 unsigned int node)
1500 {
1501 int status;
1502 int ret;
1503 struct dlm_assert_joined assert_msg;
1504
1505 mlog(0, "Sending join assert to node %u\n", node);
1506
1507 memset(&assert_msg, 0, sizeof(assert_msg));
1508 assert_msg.node_idx = dlm->node_num;
1509 assert_msg.name_len = strlen(dlm->name);
1510 memcpy(assert_msg.domain, dlm->name, assert_msg.name_len);
1511
1512 status = o2net_send_message(DLM_ASSERT_JOINED_MSG, DLM_MOD_KEY,
1513 &assert_msg, sizeof(assert_msg), node,
1514 &ret);
1515 if (status < 0)
1516 mlog(ML_ERROR, "Error %d when sending message %u (key 0x%x) to "
1517 "node %u\n", status, DLM_ASSERT_JOINED_MSG, DLM_MOD_KEY,
1518 node);
1519 else
1520 status = ret;
1521
1522 return status;
1523 }
1524
1525 static void dlm_send_join_asserts(struct dlm_ctxt *dlm,
1526 unsigned long *node_map)
1527 {
1528 int status, node, live;
1529
1530 node = -1;
1531 while ((node = find_next_bit(node_map, O2NM_MAX_NODES,
1532 node + 1)) < O2NM_MAX_NODES) {
1533 if (node == dlm->node_num)
1534 continue;
1535
1536 do {
1537 /* It is very important that this message be
1538 * received so we spin until either the node
1539 * has died or it gets the message. */
1540 status = dlm_send_one_join_assert(dlm, node);
1541
1542 spin_lock(&dlm->spinlock);
1543 live = test_bit(node, dlm->live_nodes_map);
1544 spin_unlock(&dlm->spinlock);
1545
1546 if (status) {
1547 mlog(ML_ERROR, "Error return %d asserting "
1548 "join on node %d\n", status, node);
1549
1550 /* give us some time between errors... */
1551 if (live)
1552 msleep(DLM_DOMAIN_BACKOFF_MS);
1553 }
1554 } while (status && live);
1555 }
1556 }
1557
1558 struct domain_join_ctxt {
1559 unsigned long live_map[BITS_TO_LONGS(O2NM_MAX_NODES)];
1560 unsigned long yes_resp_map[BITS_TO_LONGS(O2NM_MAX_NODES)];
1561 };
1562
1563 static int dlm_should_restart_join(struct dlm_ctxt *dlm,
1564 struct domain_join_ctxt *ctxt,
1565 enum dlm_query_join_response_code response)
1566 {
1567 int ret;
1568
1569 if (response == JOIN_DISALLOW) {
1570 mlog(0, "Latest response of disallow -- should restart\n");
1571 return 1;
1572 }
1573
1574 spin_lock(&dlm->spinlock);
1575 /* For now, we restart the process if the node maps have
1576 * changed at all */
1577 ret = !bitmap_equal(ctxt->live_map, dlm->live_nodes_map,
1578 O2NM_MAX_NODES);
1579 spin_unlock(&dlm->spinlock);
1580
1581 if (ret)
1582 mlog(0, "Node maps changed -- should restart\n");
1583
1584 return ret;
1585 }
1586
1587 static int dlm_try_to_join_domain(struct dlm_ctxt *dlm)
1588 {
1589 int status = 0, tmpstat, node;
1590 struct domain_join_ctxt *ctxt;
1591 enum dlm_query_join_response_code response = JOIN_DISALLOW;
1592
1593 mlog(0, "%p", dlm);
1594
1595 ctxt = kzalloc(sizeof(*ctxt), GFP_KERNEL);
1596 if (!ctxt) {
1597 status = -ENOMEM;
1598 mlog_errno(status);
1599 goto bail;
1600 }
1601
1602 /* group sem locking should work for us here -- we're already
1603 * registered for heartbeat events so filling this should be
1604 * atomic wrt getting those handlers called. */
1605 o2hb_fill_node_map(dlm->live_nodes_map, O2NM_MAX_NODES);
1606
1607 spin_lock(&dlm->spinlock);
1608 bitmap_copy(ctxt->live_map, dlm->live_nodes_map, O2NM_MAX_NODES);
1609 __dlm_set_joining_node(dlm, dlm->node_num);
1610 spin_unlock(&dlm->spinlock);
1611
1612 node = -1;
1613 while ((node = find_next_bit(ctxt->live_map, O2NM_MAX_NODES,
1614 node + 1)) < O2NM_MAX_NODES) {
1615 if (node == dlm->node_num)
1616 continue;
1617
1618 status = dlm_request_join(dlm, node, &response);
1619 if (status < 0) {
1620 mlog_errno(status);
1621 goto bail;
1622 }
1623
1624 /* Ok, either we got a response or the node doesn't have a
1625 * dlm up. */
1626 if (response == JOIN_OK)
1627 set_bit(node, ctxt->yes_resp_map);
1628
1629 if (dlm_should_restart_join(dlm, ctxt, response)) {
1630 status = -EAGAIN;
1631 goto bail;
1632 }
1633 }
1634
1635 mlog(0, "Yay, done querying nodes!\n");
1636
1637 /* Yay, everyone agree's we can join the domain. My domain is
1638 * comprised of all nodes who were put in the
1639 * yes_resp_map. Copy that into our domain map and send a join
1640 * assert message to clean up everyone elses state. */
1641 spin_lock(&dlm->spinlock);
1642 bitmap_copy(dlm->domain_map, ctxt->yes_resp_map, O2NM_MAX_NODES);
1643 set_bit(dlm->node_num, dlm->domain_map);
1644 spin_unlock(&dlm->spinlock);
1645
1646 /* Support for global heartbeat and node info was added in 1.1 */
1647 if (dlm->dlm_locking_proto.pv_major > 1 ||
1648 dlm->dlm_locking_proto.pv_minor > 0) {
1649 status = dlm_send_nodeinfo(dlm, ctxt->yes_resp_map);
1650 if (status) {
1651 mlog_errno(status);
1652 goto bail;
1653 }
1654 status = dlm_send_regions(dlm, ctxt->yes_resp_map);
1655 if (status) {
1656 mlog_errno(status);
1657 goto bail;
1658 }
1659 }
1660
1661 dlm_send_join_asserts(dlm, ctxt->yes_resp_map);
1662
1663 /* Joined state *must* be set before the joining node
1664 * information, otherwise the query_join handler may read no
1665 * current joiner but a state of NEW and tell joining nodes
1666 * we're not in the domain. */
1667 spin_lock(&dlm_domain_lock);
1668 dlm->dlm_state = DLM_CTXT_JOINED;
1669 dlm->num_joins++;
1670 spin_unlock(&dlm_domain_lock);
1671
1672 bail:
1673 spin_lock(&dlm->spinlock);
1674 __dlm_set_joining_node(dlm, DLM_LOCK_RES_OWNER_UNKNOWN);
1675 if (!status) {
1676 printk(KERN_NOTICE "o2dlm: Joining domain %s ", dlm->name);
1677 __dlm_print_nodes(dlm);
1678 }
1679 spin_unlock(&dlm->spinlock);
1680
1681 if (ctxt) {
1682 /* Do we need to send a cancel message to any nodes? */
1683 if (status < 0) {
1684 tmpstat = dlm_send_join_cancels(dlm,
1685 ctxt->yes_resp_map,
1686 sizeof(ctxt->yes_resp_map));
1687 if (tmpstat < 0)
1688 mlog_errno(tmpstat);
1689 }
1690 kfree(ctxt);
1691 }
1692
1693 mlog(0, "returning %d\n", status);
1694 return status;
1695 }
1696
1697 static void dlm_unregister_domain_handlers(struct dlm_ctxt *dlm)
1698 {
1699 o2hb_unregister_callback(dlm->name, &dlm->dlm_hb_up);
1700 o2hb_unregister_callback(dlm->name, &dlm->dlm_hb_down);
1701 o2net_unregister_handler_list(&dlm->dlm_domain_handlers);
1702 }
1703
1704 static int dlm_register_domain_handlers(struct dlm_ctxt *dlm)
1705 {
1706 int status;
1707
1708 mlog(0, "registering handlers.\n");
1709
1710 o2hb_setup_callback(&dlm->dlm_hb_down, O2HB_NODE_DOWN_CB,
1711 dlm_hb_node_down_cb, dlm, DLM_HB_NODE_DOWN_PRI);
1712 o2hb_setup_callback(&dlm->dlm_hb_up, O2HB_NODE_UP_CB,
1713 dlm_hb_node_up_cb, dlm, DLM_HB_NODE_UP_PRI);
1714
1715 status = o2hb_register_callback(dlm->name, &dlm->dlm_hb_down);
1716 if (status)
1717 goto bail;
1718
1719 status = o2hb_register_callback(dlm->name, &dlm->dlm_hb_up);
1720 if (status)
1721 goto bail;
1722
1723 status = o2net_register_handler(DLM_MASTER_REQUEST_MSG, dlm->key,
1724 sizeof(struct dlm_master_request),
1725 dlm_master_request_handler,
1726 dlm, NULL, &dlm->dlm_domain_handlers);
1727 if (status)
1728 goto bail;
1729
1730 status = o2net_register_handler(DLM_ASSERT_MASTER_MSG, dlm->key,
1731 sizeof(struct dlm_assert_master),
1732 dlm_assert_master_handler,
1733 dlm, dlm_assert_master_post_handler,
1734 &dlm->dlm_domain_handlers);
1735 if (status)
1736 goto bail;
1737
1738 status = o2net_register_handler(DLM_CREATE_LOCK_MSG, dlm->key,
1739 sizeof(struct dlm_create_lock),
1740 dlm_create_lock_handler,
1741 dlm, NULL, &dlm->dlm_domain_handlers);
1742 if (status)
1743 goto bail;
1744
1745 status = o2net_register_handler(DLM_CONVERT_LOCK_MSG, dlm->key,
1746 DLM_CONVERT_LOCK_MAX_LEN,
1747 dlm_convert_lock_handler,
1748 dlm, NULL, &dlm->dlm_domain_handlers);
1749 if (status)
1750 goto bail;
1751
1752 status = o2net_register_handler(DLM_UNLOCK_LOCK_MSG, dlm->key,
1753 DLM_UNLOCK_LOCK_MAX_LEN,
1754 dlm_unlock_lock_handler,
1755 dlm, NULL, &dlm->dlm_domain_handlers);
1756 if (status)
1757 goto bail;
1758
1759 status = o2net_register_handler(DLM_PROXY_AST_MSG, dlm->key,
1760 DLM_PROXY_AST_MAX_LEN,
1761 dlm_proxy_ast_handler,
1762 dlm, NULL, &dlm->dlm_domain_handlers);
1763 if (status)
1764 goto bail;
1765
1766 status = o2net_register_handler(DLM_EXIT_DOMAIN_MSG, dlm->key,
1767 sizeof(struct dlm_exit_domain),
1768 dlm_exit_domain_handler,
1769 dlm, NULL, &dlm->dlm_domain_handlers);
1770 if (status)
1771 goto bail;
1772
1773 status = o2net_register_handler(DLM_DEREF_LOCKRES_MSG, dlm->key,
1774 sizeof(struct dlm_deref_lockres),
1775 dlm_deref_lockres_handler,
1776 dlm, NULL, &dlm->dlm_domain_handlers);
1777 if (status)
1778 goto bail;
1779
1780 status = o2net_register_handler(DLM_MIGRATE_REQUEST_MSG, dlm->key,
1781 sizeof(struct dlm_migrate_request),
1782 dlm_migrate_request_handler,
1783 dlm, NULL, &dlm->dlm_domain_handlers);
1784 if (status)
1785 goto bail;
1786
1787 status = o2net_register_handler(DLM_MIG_LOCKRES_MSG, dlm->key,
1788 DLM_MIG_LOCKRES_MAX_LEN,
1789 dlm_mig_lockres_handler,
1790 dlm, NULL, &dlm->dlm_domain_handlers);
1791 if (status)
1792 goto bail;
1793
1794 status = o2net_register_handler(DLM_MASTER_REQUERY_MSG, dlm->key,
1795 sizeof(struct dlm_master_requery),
1796 dlm_master_requery_handler,
1797 dlm, NULL, &dlm->dlm_domain_handlers);
1798 if (status)
1799 goto bail;
1800
1801 status = o2net_register_handler(DLM_LOCK_REQUEST_MSG, dlm->key,
1802 sizeof(struct dlm_lock_request),
1803 dlm_request_all_locks_handler,
1804 dlm, NULL, &dlm->dlm_domain_handlers);
1805 if (status)
1806 goto bail;
1807
1808 status = o2net_register_handler(DLM_RECO_DATA_DONE_MSG, dlm->key,
1809 sizeof(struct dlm_reco_data_done),
1810 dlm_reco_data_done_handler,
1811 dlm, NULL, &dlm->dlm_domain_handlers);
1812 if (status)
1813 goto bail;
1814
1815 status = o2net_register_handler(DLM_BEGIN_RECO_MSG, dlm->key,
1816 sizeof(struct dlm_begin_reco),
1817 dlm_begin_reco_handler,
1818 dlm, NULL, &dlm->dlm_domain_handlers);
1819 if (status)
1820 goto bail;
1821
1822 status = o2net_register_handler(DLM_FINALIZE_RECO_MSG, dlm->key,
1823 sizeof(struct dlm_finalize_reco),
1824 dlm_finalize_reco_handler,
1825 dlm, NULL, &dlm->dlm_domain_handlers);
1826 if (status)
1827 goto bail;
1828
1829 status = o2net_register_handler(DLM_BEGIN_EXIT_DOMAIN_MSG, dlm->key,
1830 sizeof(struct dlm_exit_domain),
1831 dlm_begin_exit_domain_handler,
1832 dlm, NULL, &dlm->dlm_domain_handlers);
1833 if (status)
1834 goto bail;
1835
1836 status = o2net_register_handler(DLM_DEREF_LOCKRES_DONE, dlm->key,
1837 sizeof(struct dlm_deref_lockres_done),
1838 dlm_deref_lockres_done_handler,
1839 dlm, NULL, &dlm->dlm_domain_handlers);
1840 bail:
1841 if (status)
1842 dlm_unregister_domain_handlers(dlm);
1843
1844 return status;
1845 }
1846
1847 static int dlm_join_domain(struct dlm_ctxt *dlm)
1848 {
1849 int status;
1850 unsigned int backoff;
1851 unsigned int total_backoff = 0;
1852 char wq_name[O2NM_MAX_NAME_LEN];
1853
1854 BUG_ON(!dlm);
1855
1856 mlog(0, "Join domain %s\n", dlm->name);
1857
1858 status = dlm_register_domain_handlers(dlm);
1859 if (status) {
1860 mlog_errno(status);
1861 goto bail;
1862 }
1863
1864 status = dlm_launch_thread(dlm);
1865 if (status < 0) {
1866 mlog_errno(status);
1867 goto bail;
1868 }
1869
1870 status = dlm_launch_recovery_thread(dlm);
1871 if (status < 0) {
1872 mlog_errno(status);
1873 goto bail;
1874 }
1875
1876 dlm_debug_init(dlm);
1877
1878 snprintf(wq_name, O2NM_MAX_NAME_LEN, "dlm_wq-%s", dlm->name);
1879 dlm->dlm_worker = alloc_workqueue(wq_name, WQ_MEM_RECLAIM, 0);
1880 if (!dlm->dlm_worker) {
1881 status = -ENOMEM;
1882 mlog_errno(status);
1883 goto bail;
1884 }
1885
1886 do {
1887 status = dlm_try_to_join_domain(dlm);
1888
1889 /* If we're racing another node to the join, then we
1890 * need to back off temporarily and let them
1891 * complete. */
1892 #define DLM_JOIN_TIMEOUT_MSECS 90000
1893 if (status == -EAGAIN) {
1894 if (signal_pending(current)) {
1895 status = -ERESTARTSYS;
1896 goto bail;
1897 }
1898
1899 if (total_backoff > DLM_JOIN_TIMEOUT_MSECS) {
1900 status = -ERESTARTSYS;
1901 mlog(ML_NOTICE, "Timed out joining dlm domain "
1902 "%s after %u msecs\n", dlm->name,
1903 total_backoff);
1904 goto bail;
1905 }
1906
1907 /*
1908 * <chip> After you!
1909 * <dale> No, after you!
1910 * <chip> I insist!
1911 * <dale> But you first!
1912 * ...
1913 */
1914 backoff = (unsigned int)(jiffies & 0x3);
1915 backoff *= DLM_DOMAIN_BACKOFF_MS;
1916 total_backoff += backoff;
1917 mlog(0, "backoff %d\n", backoff);
1918 msleep(backoff);
1919 }
1920 } while (status == -EAGAIN);
1921
1922 if (status < 0) {
1923 mlog_errno(status);
1924 goto bail;
1925 }
1926
1927 status = 0;
1928 bail:
1929 wake_up(&dlm_domain_events);
1930
1931 if (status) {
1932 dlm_unregister_domain_handlers(dlm);
1933 dlm_complete_thread(dlm);
1934 dlm_complete_recovery_thread(dlm);
1935 dlm_destroy_dlm_worker(dlm);
1936 }
1937
1938 return status;
1939 }
1940
1941 static struct dlm_ctxt *dlm_alloc_ctxt(const char *domain,
1942 u32 key)
1943 {
1944 int i;
1945 int ret;
1946 struct dlm_ctxt *dlm = NULL;
1947
1948 dlm = kzalloc(sizeof(*dlm), GFP_KERNEL);
1949 if (!dlm) {
1950 ret = -ENOMEM;
1951 mlog_errno(ret);
1952 goto leave;
1953 }
1954
1955 dlm->name = kstrdup(domain, GFP_KERNEL);
1956 if (dlm->name == NULL) {
1957 ret = -ENOMEM;
1958 mlog_errno(ret);
1959 goto leave;
1960 }
1961
1962 dlm->lockres_hash = (struct hlist_head **)dlm_alloc_pagevec(DLM_HASH_PAGES);
1963 if (!dlm->lockres_hash) {
1964 ret = -ENOMEM;
1965 mlog_errno(ret);
1966 goto leave;
1967 }
1968
1969 for (i = 0; i < DLM_HASH_BUCKETS; i++)
1970 INIT_HLIST_HEAD(dlm_lockres_hash(dlm, i));
1971
1972 dlm->master_hash = (struct hlist_head **)
1973 dlm_alloc_pagevec(DLM_HASH_PAGES);
1974 if (!dlm->master_hash) {
1975 ret = -ENOMEM;
1976 mlog_errno(ret);
1977 goto leave;
1978 }
1979
1980 for (i = 0; i < DLM_HASH_BUCKETS; i++)
1981 INIT_HLIST_HEAD(dlm_master_hash(dlm, i));
1982
1983 dlm->key = key;
1984 dlm->node_num = o2nm_this_node();
1985
1986 dlm_create_debugfs_subroot(dlm);
1987
1988 spin_lock_init(&dlm->spinlock);
1989 spin_lock_init(&dlm->master_lock);
1990 spin_lock_init(&dlm->ast_lock);
1991 spin_lock_init(&dlm->track_lock);
1992 INIT_LIST_HEAD(&dlm->list);
1993 INIT_LIST_HEAD(&dlm->dirty_list);
1994 INIT_LIST_HEAD(&dlm->reco.resources);
1995 INIT_LIST_HEAD(&dlm->reco.node_data);
1996 INIT_LIST_HEAD(&dlm->purge_list);
1997 INIT_LIST_HEAD(&dlm->dlm_domain_handlers);
1998 INIT_LIST_HEAD(&dlm->tracking_list);
1999 dlm->reco.state = 0;
2000
2001 INIT_LIST_HEAD(&dlm->pending_asts);
2002 INIT_LIST_HEAD(&dlm->pending_basts);
2003
2004 mlog(0, "dlm->recovery_map=%p, &(dlm->recovery_map[0])=%p\n",
2005 dlm->recovery_map, &(dlm->recovery_map[0]));
2006
2007 bitmap_zero(dlm->recovery_map, O2NM_MAX_NODES);
2008 bitmap_zero(dlm->live_nodes_map, O2NM_MAX_NODES);
2009 bitmap_zero(dlm->domain_map, O2NM_MAX_NODES);
2010
2011 dlm->dlm_thread_task = NULL;
2012 dlm->dlm_reco_thread_task = NULL;
2013 dlm->dlm_worker = NULL;
2014 init_waitqueue_head(&dlm->dlm_thread_wq);
2015 init_waitqueue_head(&dlm->dlm_reco_thread_wq);
2016 init_waitqueue_head(&dlm->reco.event);
2017 init_waitqueue_head(&dlm->ast_wq);
2018 init_waitqueue_head(&dlm->migration_wq);
2019 INIT_LIST_HEAD(&dlm->mle_hb_events);
2020
2021 dlm->joining_node = DLM_LOCK_RES_OWNER_UNKNOWN;
2022 init_waitqueue_head(&dlm->dlm_join_events);
2023
2024 dlm->migrate_done = 0;
2025
2026 dlm->reco.new_master = O2NM_INVALID_NODE_NUM;
2027 dlm->reco.dead_node = O2NM_INVALID_NODE_NUM;
2028
2029 atomic_set(&dlm->res_tot_count, 0);
2030 atomic_set(&dlm->res_cur_count, 0);
2031 for (i = 0; i < DLM_MLE_NUM_TYPES; ++i) {
2032 atomic_set(&dlm->mle_tot_count[i], 0);
2033 atomic_set(&dlm->mle_cur_count[i], 0);
2034 }
2035
2036 spin_lock_init(&dlm->work_lock);
2037 INIT_LIST_HEAD(&dlm->work_list);
2038 INIT_WORK(&dlm->dispatched_work, dlm_dispatch_work);
2039
2040 kref_init(&dlm->dlm_refs);
2041 dlm->dlm_state = DLM_CTXT_NEW;
2042
2043 INIT_LIST_HEAD(&dlm->dlm_eviction_callbacks);
2044
2045 mlog(0, "context init: refcount %u\n",
2046 kref_read(&dlm->dlm_refs));
2047
2048 ret = 0;
2049 leave:
2050 if (ret < 0 && dlm) {
2051 if (dlm->master_hash)
2052 dlm_free_pagevec((void **)dlm->master_hash,
2053 DLM_HASH_PAGES);
2054
2055 if (dlm->lockres_hash)
2056 dlm_free_pagevec((void **)dlm->lockres_hash,
2057 DLM_HASH_PAGES);
2058
2059 kfree(dlm->name);
2060 kfree(dlm);
2061 dlm = NULL;
2062 }
2063 return dlm;
2064 }
2065
2066 /*
2067 * Compare a requested locking protocol version against the current one.
2068 *
2069 * If the major numbers are different, they are incompatible.
2070 * If the current minor is greater than the request, they are incompatible.
2071 * If the current minor is less than or equal to the request, they are
2072 * compatible, and the requester should run at the current minor version.
2073 */
2074 static int dlm_protocol_compare(struct dlm_protocol_version *existing,
2075 struct dlm_protocol_version *request)
2076 {
2077 if (existing->pv_major != request->pv_major)
2078 return 1;
2079
2080 if (existing->pv_minor > request->pv_minor)
2081 return 1;
2082
2083 if (existing->pv_minor < request->pv_minor)
2084 request->pv_minor = existing->pv_minor;
2085
2086 return 0;
2087 }
2088
2089 /*
2090 * dlm_register_domain: one-time setup per "domain".
2091 *
2092 * The filesystem passes in the requested locking version via proto.
2093 * If registration was successful, proto will contain the negotiated
2094 * locking protocol.
2095 */
2096 struct dlm_ctxt * dlm_register_domain(const char *domain,
2097 u32 key,
2098 struct dlm_protocol_version *fs_proto)
2099 {
2100 int ret;
2101 struct dlm_ctxt *dlm = NULL;
2102 struct dlm_ctxt *new_ctxt = NULL;
2103
2104 if (strlen(domain) >= O2NM_MAX_NAME_LEN) {
2105 ret = -ENAMETOOLONG;
2106 mlog(ML_ERROR, "domain name length too long\n");
2107 goto leave;
2108 }
2109
2110 mlog(0, "register called for domain \"%s\"\n", domain);
2111
2112 retry:
2113 dlm = NULL;
2114 if (signal_pending(current)) {
2115 ret = -ERESTARTSYS;
2116 mlog_errno(ret);
2117 goto leave;
2118 }
2119
2120 spin_lock(&dlm_domain_lock);
2121
2122 dlm = __dlm_lookup_domain(domain);
2123 if (dlm) {
2124 if (dlm->dlm_state != DLM_CTXT_JOINED) {
2125 spin_unlock(&dlm_domain_lock);
2126
2127 mlog(0, "This ctxt is not joined yet!\n");
2128 wait_event_interruptible(dlm_domain_events,
2129 dlm_wait_on_domain_helper(
2130 domain));
2131 goto retry;
2132 }
2133
2134 if (dlm_protocol_compare(&dlm->fs_locking_proto, fs_proto)) {
2135 spin_unlock(&dlm_domain_lock);
2136 mlog(ML_ERROR,
2137 "Requested locking protocol version is not "
2138 "compatible with already registered domain "
2139 "\"%s\"\n", domain);
2140 ret = -EPROTO;
2141 goto leave;
2142 }
2143
2144 __dlm_get(dlm);
2145 dlm->num_joins++;
2146
2147 spin_unlock(&dlm_domain_lock);
2148
2149 ret = 0;
2150 goto leave;
2151 }
2152
2153 /* doesn't exist */
2154 if (!new_ctxt) {
2155 spin_unlock(&dlm_domain_lock);
2156
2157 new_ctxt = dlm_alloc_ctxt(domain, key);
2158 if (new_ctxt)
2159 goto retry;
2160
2161 ret = -ENOMEM;
2162 mlog_errno(ret);
2163 goto leave;
2164 }
2165
2166 /* a little variable switch-a-roo here... */
2167 dlm = new_ctxt;
2168 new_ctxt = NULL;
2169
2170 /* add the new domain */
2171 list_add_tail(&dlm->list, &dlm_domains);
2172 spin_unlock(&dlm_domain_lock);
2173
2174 /*
2175 * Pass the locking protocol version into the join. If the join
2176 * succeeds, it will have the negotiated protocol set.
2177 */
2178 dlm->dlm_locking_proto = dlm_protocol;
2179 dlm->fs_locking_proto = *fs_proto;
2180
2181 ret = dlm_join_domain(dlm);
2182 if (ret) {
2183 mlog_errno(ret);
2184 dlm_put(dlm);
2185 goto leave;
2186 }
2187
2188 /* Tell the caller what locking protocol we negotiated */
2189 *fs_proto = dlm->fs_locking_proto;
2190
2191 ret = 0;
2192 leave:
2193 if (new_ctxt)
2194 dlm_free_ctxt_mem(new_ctxt);
2195
2196 if (ret < 0)
2197 dlm = ERR_PTR(ret);
2198
2199 return dlm;
2200 }
2201 EXPORT_SYMBOL_GPL(dlm_register_domain);
2202
2203 static LIST_HEAD(dlm_join_handlers);
2204
2205 static void dlm_unregister_net_handlers(void)
2206 {
2207 o2net_unregister_handler_list(&dlm_join_handlers);
2208 }
2209
2210 static int dlm_register_net_handlers(void)
2211 {
2212 int status = 0;
2213
2214 status = o2net_register_handler(DLM_QUERY_JOIN_MSG, DLM_MOD_KEY,
2215 sizeof(struct dlm_query_join_request),
2216 dlm_query_join_handler,
2217 NULL, NULL, &dlm_join_handlers);
2218 if (status)
2219 goto bail;
2220
2221 status = o2net_register_handler(DLM_ASSERT_JOINED_MSG, DLM_MOD_KEY,
2222 sizeof(struct dlm_assert_joined),
2223 dlm_assert_joined_handler,
2224 NULL, NULL, &dlm_join_handlers);
2225 if (status)
2226 goto bail;
2227
2228 status = o2net_register_handler(DLM_CANCEL_JOIN_MSG, DLM_MOD_KEY,
2229 sizeof(struct dlm_cancel_join),
2230 dlm_cancel_join_handler,
2231 NULL, NULL, &dlm_join_handlers);
2232 if (status)
2233 goto bail;
2234
2235 status = o2net_register_handler(DLM_QUERY_REGION, DLM_MOD_KEY,
2236 sizeof(struct dlm_query_region),
2237 dlm_query_region_handler,
2238 NULL, NULL, &dlm_join_handlers);
2239
2240 if (status)
2241 goto bail;
2242
2243 status = o2net_register_handler(DLM_QUERY_NODEINFO, DLM_MOD_KEY,
2244 sizeof(struct dlm_query_nodeinfo),
2245 dlm_query_nodeinfo_handler,
2246 NULL, NULL, &dlm_join_handlers);
2247 bail:
2248 if (status < 0)
2249 dlm_unregister_net_handlers();
2250
2251 return status;
2252 }
2253
2254 /* Domain eviction callback handling.
2255 *
2256 * The file system requires notification of node death *before* the
2257 * dlm completes it's recovery work, otherwise it may be able to
2258 * acquire locks on resources requiring recovery. Since the dlm can
2259 * evict a node from it's domain *before* heartbeat fires, a similar
2260 * mechanism is required. */
2261
2262 /* Eviction is not expected to happen often, so a per-domain lock is
2263 * not necessary. Eviction callbacks are allowed to sleep for short
2264 * periods of time. */
2265 static DECLARE_RWSEM(dlm_callback_sem);
2266
2267 void dlm_fire_domain_eviction_callbacks(struct dlm_ctxt *dlm,
2268 int node_num)
2269 {
2270 struct dlm_eviction_cb *cb;
2271
2272 down_read(&dlm_callback_sem);
2273 list_for_each_entry(cb, &dlm->dlm_eviction_callbacks, ec_item) {
2274 cb->ec_func(node_num, cb->ec_data);
2275 }
2276 up_read(&dlm_callback_sem);
2277 }
2278
2279 void dlm_setup_eviction_cb(struct dlm_eviction_cb *cb,
2280 dlm_eviction_func *f,
2281 void *data)
2282 {
2283 INIT_LIST_HEAD(&cb->ec_item);
2284 cb->ec_func = f;
2285 cb->ec_data = data;
2286 }
2287 EXPORT_SYMBOL_GPL(dlm_setup_eviction_cb);
2288
2289 void dlm_register_eviction_cb(struct dlm_ctxt *dlm,
2290 struct dlm_eviction_cb *cb)
2291 {
2292 down_write(&dlm_callback_sem);
2293 list_add_tail(&cb->ec_item, &dlm->dlm_eviction_callbacks);
2294 up_write(&dlm_callback_sem);
2295 }
2296 EXPORT_SYMBOL_GPL(dlm_register_eviction_cb);
2297
2298 void dlm_unregister_eviction_cb(struct dlm_eviction_cb *cb)
2299 {
2300 down_write(&dlm_callback_sem);
2301 list_del_init(&cb->ec_item);
2302 up_write(&dlm_callback_sem);
2303 }
2304 EXPORT_SYMBOL_GPL(dlm_unregister_eviction_cb);
2305
2306 static int __init dlm_init(void)
2307 {
2308 int status;
2309
2310 status = dlm_init_mle_cache();
2311 if (status) {
2312 mlog(ML_ERROR, "Could not create o2dlm_mle slabcache\n");
2313 goto error;
2314 }
2315
2316 status = dlm_init_master_caches();
2317 if (status) {
2318 mlog(ML_ERROR, "Could not create o2dlm_lockres and "
2319 "o2dlm_lockname slabcaches\n");
2320 goto error;
2321 }
2322
2323 status = dlm_init_lock_cache();
2324 if (status) {
2325 mlog(ML_ERROR, "Count not create o2dlm_lock slabcache\n");
2326 goto error;
2327 }
2328
2329 status = dlm_register_net_handlers();
2330 if (status) {
2331 mlog(ML_ERROR, "Unable to register network handlers\n");
2332 goto error;
2333 }
2334
2335 dlm_create_debugfs_root();
2336
2337 return 0;
2338 error:
2339 dlm_unregister_net_handlers();
2340 dlm_destroy_lock_cache();
2341 dlm_destroy_master_caches();
2342 dlm_destroy_mle_cache();
2343 return -1;
2344 }
2345
2346 static void __exit dlm_exit (void)
2347 {
2348 dlm_destroy_debugfs_root();
2349 dlm_unregister_net_handlers();
2350 dlm_destroy_lock_cache();
2351 dlm_destroy_master_caches();
2352 dlm_destroy_mle_cache();
2353 }
2354
2355 MODULE_AUTHOR("Oracle");
2356 MODULE_LICENSE("GPL");
2357 MODULE_DESCRIPTION("OCFS2 Distributed Lock Management");
2358
2359 module_init(dlm_init);
2360 module_exit(dlm_exit);
Linux kernel stable tree