1 /* -*- mode: c; c-basic-offset: 8; -*-
2 * vim: noexpandtab sw=8 ts=8 sts=0:
3 *
4 * dlmdomain.c
5 *
6 * defines domain join / leave apis
7 *
8 * Copyright (C) 2004 Oracle. All rights reserved.
9 *
10 * This program is free software; you can redistribute it and/or
11 * modify it under the terms of the GNU General Public
12 * License as published by the Free Software Foundation; either
13 * version 2 of the License, or (at your option) any later version.
14 *
15 * This program is distributed in the hope that it will be useful,
16 * but WITHOUT ANY WARRANTY; without even the implied warranty of
17 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
18 * General Public License for more details.
19 *
20 * You should have received a copy of the GNU General Public
21 * License along with this program; if not, write to the
22 * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
23 * Boston, MA 021110-1307, USA.
24 *
25 */
26
27 #include <linux/module.h>
28 #include <linux/types.h>
29 #include <linux/slab.h>
30 #include <linux/highmem.h>
31 #include <linux/init.h>
32 #include <linux/spinlock.h>
33 #include <linux/delay.h>
34 #include <linux/err.h>
35 #include <linux/debugfs.h>
36
37 #include "cluster/heartbeat.h"
38 #include "cluster/nodemanager.h"
39 #include "cluster/tcp.h"
40
41 #include "dlmapi.h"
42 #include "dlmcommon.h"
43 #include "dlmdomain.h"
44 #include "dlmdebug.h"
45
46 #include "dlmver.h"
47
48 #define MLOG_MASK_PREFIX (ML_DLM|ML_DLM_DOMAIN)
49 #include "cluster/masklog.h"
50
51 /*
52 * ocfs2 node maps are array of long int, which limits to send them freely
53 * across the wire due to endianness issues. To workaround this, we convert
54 * long ints to byte arrays. Following 3 routines are helper functions to
55 * set/test/copy bits within those array of bytes
56 */
byte_set_bit(u8 nr,u8 map[])57 static inline void byte_set_bit(u8 nr, u8 map[])
58 {
59 map[nr >> 3] |= (1UL << (nr & 7));
60 }
61
byte_test_bit(u8 nr,u8 map[])62 static inline int byte_test_bit(u8 nr, u8 map[])
63 {
64 return ((1UL << (nr & 7)) & (map[nr >> 3])) != 0;
65 }
66
byte_copymap(u8 dmap[],unsigned long smap[],unsigned int sz)67 static inline void byte_copymap(u8 dmap[], unsigned long smap[],
68 unsigned int sz)
69 {
70 unsigned int nn;
71
72 if (!sz)
73 return;
74
75 memset(dmap, 0, ((sz + 7) >> 3));
76 for (nn = 0 ; nn < sz; nn++)
77 if (test_bit(nn, smap))
78 byte_set_bit(nn, dmap);
79 }
80
dlm_free_pagevec(void ** vec,int pages)81 static void dlm_free_pagevec(void **vec, int pages)
82 {
83 while (pages--)
84 free_page((unsigned long)vec[pages]);
85 kfree(vec);
86 }
87
dlm_alloc_pagevec(int pages)88 static void **dlm_alloc_pagevec(int pages)
89 {
90 void **vec = kmalloc(pages * sizeof(void *), GFP_KERNEL);
91 int i;
92
93 if (!vec)
94 return NULL;
95
96 for (i = 0; i < pages; i++)
97 if (!(vec[i] = (void *)__get_free_page(GFP_KERNEL)))
98 goto out_free;
99
100 mlog(0, "Allocated DLM hash pagevec; %d pages (%lu expected), %lu buckets per page\n",
101 pages, (unsigned long)DLM_HASH_PAGES,
102 (unsigned long)DLM_BUCKETS_PER_PAGE);
103 return vec;
104 out_free:
105 dlm_free_pagevec(vec, i);
106 return NULL;
107 }
108
109 /*
110 *
111 * spinlock lock ordering: if multiple locks are needed, obey this ordering:
112 * dlm_domain_lock
113 * struct dlm_ctxt->spinlock
114 * struct dlm_lock_resource->spinlock
115 * struct dlm_ctxt->master_lock
116 * struct dlm_ctxt->ast_lock
117 * dlm_master_list_entry->spinlock
118 * dlm_lock->spinlock
119 *
120 */
121
122 DEFINE_SPINLOCK(dlm_domain_lock);
123 LIST_HEAD(dlm_domains);
124 static DECLARE_WAIT_QUEUE_HEAD(dlm_domain_events);
125
126 /*
127 * The supported protocol version for DLM communication. Running domains
128 * will have a negotiated version with the same major number and a minor
129 * number equal or smaller. The dlm_ctxt->dlm_locking_proto field should
130 * be used to determine what a running domain is actually using.
131 *
132 * New in version 1.1:
133 * - Message DLM_QUERY_REGION added to support global heartbeat
134 * - Message DLM_QUERY_NODEINFO added to allow online node removes
135 */
136 static const struct dlm_protocol_version dlm_protocol = {
137 .pv_major = 1,
138 .pv_minor = 1,
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
__dlm_unhash_lockres(struct dlm_lock_resource * lockres)158 void __dlm_unhash_lockres(struct dlm_lock_resource *lockres)
159 {
160 if (!hlist_unhashed(&lockres->hash_node)) {
161 hlist_del_init(&lockres->hash_node);
162 dlm_lockres_put(lockres);
163 }
164 }
165
__dlm_insert_lockres(struct dlm_ctxt * dlm,struct dlm_lock_resource * res)166 void __dlm_insert_lockres(struct dlm_ctxt *dlm,
167 struct dlm_lock_resource *res)
168 {
169 struct hlist_head *bucket;
170 struct qstr *q;
171
172 assert_spin_locked(&dlm->spinlock);
173
174 q = &res->lockname;
175 bucket = dlm_lockres_hash(dlm, q->hash);
176
177 /* get a reference for our hashtable */
178 dlm_lockres_get(res);
179
180 hlist_add_head(&res->hash_node, bucket);
181 }
182
__dlm_lookup_lockres_full(struct dlm_ctxt * dlm,const char * name,unsigned int len,unsigned int hash)183 struct dlm_lock_resource * __dlm_lookup_lockres_full(struct dlm_ctxt *dlm,
184 const char *name,
185 unsigned int len,
186 unsigned int hash)
187 {
188 struct hlist_head *bucket;
189 struct hlist_node *list;
190
191 mlog(0, "%.*s\n", len, name);
192
193 assert_spin_locked(&dlm->spinlock);
194
195 bucket = dlm_lockres_hash(dlm, hash);
196
197 hlist_for_each(list, bucket) {
198 struct dlm_lock_resource *res = hlist_entry(list,
199 struct dlm_lock_resource, hash_node);
200 if (res->lockname.name[0] != name[0])
201 continue;
202 if (unlikely(res->lockname.len != len))
203 continue;
204 if (memcmp(res->lockname.name + 1, name + 1, len - 1))
205 continue;
206 dlm_lockres_get(res);
207 return res;
208 }
209 return NULL;
210 }
211
212 /* intended to be called by functions which do not care about lock
213 * resources which are being purged (most net _handler functions).
214 * this will return NULL for any lock resource which is found but
215 * currently in the process of dropping its mastery reference.
216 * use __dlm_lookup_lockres_full when you need the lock resource
217 * regardless (e.g. dlm_get_lock_resource) */
__dlm_lookup_lockres(struct dlm_ctxt * dlm,const char * name,unsigned int len,unsigned int hash)218 struct dlm_lock_resource * __dlm_lookup_lockres(struct dlm_ctxt *dlm,
219 const char *name,
220 unsigned int len,
221 unsigned int hash)
222 {
223 struct dlm_lock_resource *res = NULL;
224
225 mlog(0, "%.*s\n", len, name);
226
227 assert_spin_locked(&dlm->spinlock);
228
229 res = __dlm_lookup_lockres_full(dlm, name, len, hash);
230 if (res) {
231 spin_lock(&res->spinlock);
232 if (res->state & DLM_LOCK_RES_DROPPING_REF) {
233 spin_unlock(&res->spinlock);
234 dlm_lockres_put(res);
235 return NULL;
236 }
237 spin_unlock(&res->spinlock);
238 }
239
240 return res;
241 }
242
dlm_lookup_lockres(struct dlm_ctxt * dlm,const char * name,unsigned int len)243 struct dlm_lock_resource * dlm_lookup_lockres(struct dlm_ctxt *dlm,
244 const char *name,
245 unsigned int len)
246 {
247 struct dlm_lock_resource *res;
248 unsigned int hash = dlm_lockid_hash(name, len);
249
250 spin_lock(&dlm->spinlock);
251 res = __dlm_lookup_lockres(dlm, name, len, hash);
252 spin_unlock(&dlm->spinlock);
253 return res;
254 }
255
__dlm_lookup_domain_full(const char * domain,int len)256 static struct dlm_ctxt * __dlm_lookup_domain_full(const char *domain, int len)
257 {
258 struct dlm_ctxt *tmp = NULL;
259 struct list_head *iter;
260
261 assert_spin_locked(&dlm_domain_lock);
262
263 /* tmp->name here is always NULL terminated,
264 * but domain may not be! */
265 list_for_each(iter, &dlm_domains) {
266 tmp = list_entry (iter, struct dlm_ctxt, list);
267 if (strlen(tmp->name) == len &&
268 memcmp(tmp->name, domain, len)==0)
269 break;
270 tmp = NULL;
271 }
272
273 return tmp;
274 }
275
276 /* For null terminated domain strings ONLY */
__dlm_lookup_domain(const char * domain)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" */
dlm_wait_on_domain_helper(const char * domain)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
dlm_free_ctxt_mem(struct dlm_ctxt * dlm)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 if (dlm->name)
316 kfree(dlm->name);
317
318 kfree(dlm);
319 }
320
321 /* A little strange - this function will be called while holding
322 * dlm_domain_lock and is expected to be holding it on the way out. We
323 * will however drop and reacquire it multiple times */
dlm_ctxt_release(struct kref * kref)324 static void dlm_ctxt_release(struct kref *kref)
325 {
326 struct dlm_ctxt *dlm;
327
328 dlm = container_of(kref, struct dlm_ctxt, dlm_refs);
329
330 BUG_ON(dlm->num_joins);
331 BUG_ON(dlm->dlm_state == DLM_CTXT_JOINED);
332
333 /* we may still be in the list if we hit an error during join. */
334 list_del_init(&dlm->list);
335
336 spin_unlock(&dlm_domain_lock);
337
338 mlog(0, "freeing memory from domain %s\n", dlm->name);
339
340 wake_up(&dlm_domain_events);
341
342 dlm_free_ctxt_mem(dlm);
343
344 spin_lock(&dlm_domain_lock);
345 }
346
dlm_put(struct dlm_ctxt * dlm)347 void dlm_put(struct dlm_ctxt *dlm)
348 {
349 spin_lock(&dlm_domain_lock);
350 kref_put(&dlm->dlm_refs, dlm_ctxt_release);
351 spin_unlock(&dlm_domain_lock);
352 }
353
__dlm_get(struct dlm_ctxt * dlm)354 static void __dlm_get(struct dlm_ctxt *dlm)
355 {
356 kref_get(&dlm->dlm_refs);
357 }
358
359 /* given a questionable reference to a dlm object, gets a reference if
360 * it can find it in the list, otherwise returns NULL in which case
361 * you shouldn't trust your pointer. */
dlm_grab(struct dlm_ctxt * dlm)362 struct dlm_ctxt *dlm_grab(struct dlm_ctxt *dlm)
363 {
364 struct list_head *iter;
365 struct dlm_ctxt *target = NULL;
366
367 spin_lock(&dlm_domain_lock);
368
369 list_for_each(iter, &dlm_domains) {
370 target = list_entry (iter, struct dlm_ctxt, list);
371
372 if (target == dlm) {
373 __dlm_get(target);
374 break;
375 }
376
377 target = NULL;
378 }
379
380 spin_unlock(&dlm_domain_lock);
381
382 return target;
383 }
384
dlm_domain_fully_joined(struct dlm_ctxt * dlm)385 int dlm_domain_fully_joined(struct dlm_ctxt *dlm)
386 {
387 int ret;
388
389 spin_lock(&dlm_domain_lock);
390 ret = (dlm->dlm_state == DLM_CTXT_JOINED) ||
391 (dlm->dlm_state == DLM_CTXT_IN_SHUTDOWN);
392 spin_unlock(&dlm_domain_lock);
393
394 return ret;
395 }
396
dlm_destroy_dlm_worker(struct dlm_ctxt * dlm)397 static void dlm_destroy_dlm_worker(struct dlm_ctxt *dlm)
398 {
399 if (dlm->dlm_worker) {
400 flush_workqueue(dlm->dlm_worker);
401 destroy_workqueue(dlm->dlm_worker);
402 dlm->dlm_worker = NULL;
403 }
404 }
405
dlm_complete_dlm_shutdown(struct dlm_ctxt * dlm)406 static void dlm_complete_dlm_shutdown(struct dlm_ctxt *dlm)
407 {
408 dlm_unregister_domain_handlers(dlm);
409 dlm_debug_shutdown(dlm);
410 dlm_complete_thread(dlm);
411 dlm_complete_recovery_thread(dlm);
412 dlm_destroy_dlm_worker(dlm);
413
414 /* We've left the domain. Now we can take ourselves out of the
415 * list and allow the kref stuff to help us free the
416 * memory. */
417 spin_lock(&dlm_domain_lock);
418 list_del_init(&dlm->list);
419 spin_unlock(&dlm_domain_lock);
420
421 /* Wake up anyone waiting for us to remove this domain */
422 wake_up(&dlm_domain_events);
423 }
424
dlm_migrate_all_locks(struct dlm_ctxt * dlm)425 static int dlm_migrate_all_locks(struct dlm_ctxt *dlm)
426 {
427 int i, num, n, ret = 0;
428 struct dlm_lock_resource *res;
429 struct hlist_node *iter;
430 struct hlist_head *bucket;
431 int dropped;
432
433 mlog(0, "Migrating locks from domain %s\n", dlm->name);
434
435 num = 0;
436 spin_lock(&dlm->spinlock);
437 for (i = 0; i < DLM_HASH_BUCKETS; i++) {
438 redo_bucket:
439 n = 0;
440 bucket = dlm_lockres_hash(dlm, i);
441 iter = bucket->first;
442 while (iter) {
443 n++;
444 res = hlist_entry(iter, struct dlm_lock_resource,
445 hash_node);
446 dlm_lockres_get(res);
447 /* migrate, if necessary. this will drop the dlm
448 * spinlock and retake it if it does migration. */
449 dropped = dlm_empty_lockres(dlm, res);
450
451 spin_lock(&res->spinlock);
452 __dlm_lockres_calc_usage(dlm, res);
453 iter = res->hash_node.next;
454 spin_unlock(&res->spinlock);
455
456 dlm_lockres_put(res);
457
458 if (dropped)
459 goto redo_bucket;
460 }
461 cond_resched_lock(&dlm->spinlock);
462 num += n;
463 }
464 spin_unlock(&dlm->spinlock);
465 wake_up(&dlm->dlm_thread_wq);
466
467 /* let the dlm thread take care of purging, keep scanning until
468 * nothing remains in the hash */
469 if (num) {
470 mlog(0, "%s: %d lock resources in hash last pass\n",
471 dlm->name, num);
472 ret = -EAGAIN;
473 }
474 mlog(0, "DONE Migrating locks from domain %s\n", dlm->name);
475 return ret;
476 }
477
dlm_no_joining_node(struct dlm_ctxt * dlm)478 static int dlm_no_joining_node(struct dlm_ctxt *dlm)
479 {
480 int ret;
481
482 spin_lock(&dlm->spinlock);
483 ret = dlm->joining_node == DLM_LOCK_RES_OWNER_UNKNOWN;
484 spin_unlock(&dlm->spinlock);
485
486 return ret;
487 }
488
dlm_mark_domain_leaving(struct dlm_ctxt * dlm)489 static void dlm_mark_domain_leaving(struct dlm_ctxt *dlm)
490 {
491 /* Yikes, a double spinlock! I need domain_lock for the dlm
492 * state and the dlm spinlock for join state... Sorry! */
493 again:
494 spin_lock(&dlm_domain_lock);
495 spin_lock(&dlm->spinlock);
496
497 if (dlm->joining_node != DLM_LOCK_RES_OWNER_UNKNOWN) {
498 mlog(0, "Node %d is joining, we wait on it.\n",
499 dlm->joining_node);
500 spin_unlock(&dlm->spinlock);
501 spin_unlock(&dlm_domain_lock);
502
503 wait_event(dlm->dlm_join_events, dlm_no_joining_node(dlm));
504 goto again;
505 }
506
507 dlm->dlm_state = DLM_CTXT_LEAVING;
508 spin_unlock(&dlm->spinlock);
509 spin_unlock(&dlm_domain_lock);
510 }
511
__dlm_print_nodes(struct dlm_ctxt * dlm)512 static void __dlm_print_nodes(struct dlm_ctxt *dlm)
513 {
514 int node = -1;
515
516 assert_spin_locked(&dlm->spinlock);
517
518 printk(KERN_NOTICE "o2dlm: Nodes in domain %s: ", dlm->name);
519
520 while ((node = find_next_bit(dlm->domain_map, O2NM_MAX_NODES,
521 node + 1)) < O2NM_MAX_NODES) {
522 printk("%d ", node);
523 }
524 printk("\n");
525 }
526
dlm_exit_domain_handler(struct o2net_msg * msg,u32 len,void * data,void ** ret_data)527 static int dlm_exit_domain_handler(struct o2net_msg *msg, u32 len, void *data,
528 void **ret_data)
529 {
530 struct dlm_ctxt *dlm = data;
531 unsigned int node;
532 struct dlm_exit_domain *exit_msg = (struct dlm_exit_domain *) msg->buf;
533
534 mlog(0, "%p %u %p", msg, len, data);
535
536 if (!dlm_grab(dlm))
537 return 0;
538
539 node = exit_msg->node_idx;
540
541 printk(KERN_NOTICE "o2dlm: Node %u leaves domain %s\n", node, dlm->name);
542
543 spin_lock(&dlm->spinlock);
544 clear_bit(node, dlm->domain_map);
545 __dlm_print_nodes(dlm);
546
547 /* notify anything attached to the heartbeat events */
548 dlm_hb_event_notify_attached(dlm, node, 0);
549
550 spin_unlock(&dlm->spinlock);
551
552 dlm_put(dlm);
553
554 return 0;
555 }
556
dlm_send_one_domain_exit(struct dlm_ctxt * dlm,unsigned int node)557 static int dlm_send_one_domain_exit(struct dlm_ctxt *dlm,
558 unsigned int node)
559 {
560 int status;
561 struct dlm_exit_domain leave_msg;
562
563 mlog(0, "Asking node %u if we can leave the domain %s me = %u\n",
564 node, dlm->name, dlm->node_num);
565
566 memset(&leave_msg, 0, sizeof(leave_msg));
567 leave_msg.node_idx = dlm->node_num;
568
569 status = o2net_send_message(DLM_EXIT_DOMAIN_MSG, dlm->key,
570 &leave_msg, sizeof(leave_msg), node,
571 NULL);
572 if (status < 0)
573 mlog(ML_ERROR, "Error %d when sending message %u (key 0x%x) to "
574 "node %u\n", status, DLM_EXIT_DOMAIN_MSG, dlm->key, node);
575 mlog(0, "status return %d from o2net_send_message\n", status);
576
577 return status;
578 }
579
580
dlm_leave_domain(struct dlm_ctxt * dlm)581 static void dlm_leave_domain(struct dlm_ctxt *dlm)
582 {
583 int node, clear_node, status;
584
585 /* At this point we've migrated away all our locks and won't
586 * accept mastership of new ones. The dlm is responsible for
587 * almost nothing now. We make sure not to confuse any joining
588 * nodes and then commence shutdown procedure. */
589
590 spin_lock(&dlm->spinlock);
591 /* Clear ourselves from the domain map */
592 clear_bit(dlm->node_num, dlm->domain_map);
593 while ((node = find_next_bit(dlm->domain_map, O2NM_MAX_NODES,
594 0)) < O2NM_MAX_NODES) {
595 /* Drop the dlm spinlock. This is safe wrt the domain_map.
596 * -nodes cannot be added now as the
597 * query_join_handlers knows to respond with OK_NO_MAP
598 * -we catch the right network errors if a node is
599 * removed from the map while we're sending him the
600 * exit message. */
601 spin_unlock(&dlm->spinlock);
602
603 clear_node = 1;
604
605 status = dlm_send_one_domain_exit(dlm, node);
606 if (status < 0 &&
607 status != -ENOPROTOOPT &&
608 status != -ENOTCONN) {
609 mlog(ML_NOTICE, "Error %d sending domain exit message "
610 "to node %d\n", status, node);
611
612 /* Not sure what to do here but lets sleep for
613 * a bit in case this was a transient
614 * error... */
615 msleep(DLM_DOMAIN_BACKOFF_MS);
616 clear_node = 0;
617 }
618
619 spin_lock(&dlm->spinlock);
620 /* If we're not clearing the node bit then we intend
621 * to loop back around to try again. */
622 if (clear_node)
623 clear_bit(node, dlm->domain_map);
624 }
625 spin_unlock(&dlm->spinlock);
626 }
627
dlm_joined(struct dlm_ctxt * dlm)628 int dlm_joined(struct dlm_ctxt *dlm)
629 {
630 int ret = 0;
631
632 spin_lock(&dlm_domain_lock);
633
634 if (dlm->dlm_state == DLM_CTXT_JOINED)
635 ret = 1;
636
637 spin_unlock(&dlm_domain_lock);
638
639 return ret;
640 }
641
dlm_shutting_down(struct dlm_ctxt * dlm)642 int dlm_shutting_down(struct dlm_ctxt *dlm)
643 {
644 int ret = 0;
645
646 spin_lock(&dlm_domain_lock);
647
648 if (dlm->dlm_state == DLM_CTXT_IN_SHUTDOWN)
649 ret = 1;
650
651 spin_unlock(&dlm_domain_lock);
652
653 return ret;
654 }
655
dlm_unregister_domain(struct dlm_ctxt * dlm)656 void dlm_unregister_domain(struct dlm_ctxt *dlm)
657 {
658 int leave = 0;
659 struct dlm_lock_resource *res;
660
661 spin_lock(&dlm_domain_lock);
662 BUG_ON(dlm->dlm_state != DLM_CTXT_JOINED);
663 BUG_ON(!dlm->num_joins);
664
665 dlm->num_joins--;
666 if (!dlm->num_joins) {
667 /* We mark it "in shutdown" now so new register
668 * requests wait until we've completely left the
669 * domain. Don't use DLM_CTXT_LEAVING yet as we still
670 * want new domain joins to communicate with us at
671 * least until we've completed migration of our
672 * resources. */
673 dlm->dlm_state = DLM_CTXT_IN_SHUTDOWN;
674 leave = 1;
675 }
676 spin_unlock(&dlm_domain_lock);
677
678 if (leave) {
679 mlog(0, "shutting down domain %s\n", dlm->name);
680
681 /* We changed dlm state, notify the thread */
682 dlm_kick_thread(dlm, NULL);
683
684 while (dlm_migrate_all_locks(dlm)) {
685 /* Give dlm_thread time to purge the lockres' */
686 msleep(500);
687 mlog(0, "%s: more migration to do\n", dlm->name);
688 }
689
690 /* This list should be empty. If not, print remaining lockres */
691 if (!list_empty(&dlm->tracking_list)) {
692 mlog(ML_ERROR, "Following lockres' are still on the "
693 "tracking list:\n");
694 list_for_each_entry(res, &dlm->tracking_list, tracking)
695 dlm_print_one_lock_resource(res);
696 }
697
698 dlm_mark_domain_leaving(dlm);
699 dlm_leave_domain(dlm);
700 dlm_force_free_mles(dlm);
701 dlm_complete_dlm_shutdown(dlm);
702 }
703 dlm_put(dlm);
704 }
705 EXPORT_SYMBOL_GPL(dlm_unregister_domain);
706
dlm_query_join_proto_check(char * proto_type,int node,struct dlm_protocol_version * ours,struct dlm_protocol_version * request)707 static int dlm_query_join_proto_check(char *proto_type, int node,
708 struct dlm_protocol_version *ours,
709 struct dlm_protocol_version *request)
710 {
711 int rc;
712 struct dlm_protocol_version proto = *request;
713
714 if (!dlm_protocol_compare(ours, &proto)) {
715 mlog(0,
716 "node %u wanted to join with %s locking protocol "
717 "%u.%u, we respond with %u.%u\n",
718 node, proto_type,
719 request->pv_major,
720 request->pv_minor,
721 proto.pv_major, proto.pv_minor);
722 request->pv_minor = proto.pv_minor;
723 rc = 0;
724 } else {
725 mlog(ML_NOTICE,
726 "Node %u wanted to join with %s locking "
727 "protocol %u.%u, but we have %u.%u, disallowing\n",
728 node, proto_type,
729 request->pv_major,
730 request->pv_minor,
731 ours->pv_major,
732 ours->pv_minor);
733 rc = 1;
734 }
735
736 return rc;
737 }
738
739 /*
740 * struct dlm_query_join_packet is made up of four one-byte fields. They
741 * are effectively in big-endian order already. However, little-endian
742 * machines swap them before putting the packet on the wire (because
743 * query_join's response is a status, and that status is treated as a u32
744 * on the wire). Thus, a big-endian and little-endian machines will treat
745 * this structure differently.
746 *
747 * The solution is to have little-endian machines swap the structure when
748 * converting from the structure to the u32 representation. This will
749 * result in the structure having the correct format on the wire no matter
750 * the host endian format.
751 */
dlm_query_join_packet_to_wire(struct dlm_query_join_packet * packet,u32 * wire)752 static void dlm_query_join_packet_to_wire(struct dlm_query_join_packet *packet,
753 u32 *wire)
754 {
755 union dlm_query_join_response response;
756
757 response.packet = *packet;
758 *wire = cpu_to_be32(response.intval);
759 }
760
dlm_query_join_wire_to_packet(u32 wire,struct dlm_query_join_packet * packet)761 static void dlm_query_join_wire_to_packet(u32 wire,
762 struct dlm_query_join_packet *packet)
763 {
764 union dlm_query_join_response response;
765
766 response.intval = cpu_to_be32(wire);
767 *packet = response.packet;
768 }
769
dlm_query_join_handler(struct o2net_msg * msg,u32 len,void * data,void ** ret_data)770 static int dlm_query_join_handler(struct o2net_msg *msg, u32 len, void *data,
771 void **ret_data)
772 {
773 struct dlm_query_join_request *query;
774 struct dlm_query_join_packet packet = {
775 .code = JOIN_DISALLOW,
776 };
777 struct dlm_ctxt *dlm = NULL;
778 u32 response;
779 u8 nodenum;
780
781 query = (struct dlm_query_join_request *) msg->buf;
782
783 mlog(0, "node %u wants to join domain %s\n", query->node_idx,
784 query->domain);
785
786 /*
787 * If heartbeat doesn't consider the node live, tell it
788 * to back off and try again. This gives heartbeat a chance
789 * to catch up.
790 */
791 if (!o2hb_check_node_heartbeating(query->node_idx)) {
792 mlog(0, "node %u is not in our live map yet\n",
793 query->node_idx);
794
795 packet.code = JOIN_DISALLOW;
796 goto respond;
797 }
798
799 packet.code = JOIN_OK_NO_MAP;
800
801 spin_lock(&dlm_domain_lock);
802 dlm = __dlm_lookup_domain_full(query->domain, query->name_len);
803 if (!dlm)
804 goto unlock_respond;
805
806 /*
807 * There is a small window where the joining node may not see the
808 * node(s) that just left but still part of the cluster. DISALLOW
809 * join request if joining node has different node map.
810 */
811 nodenum=0;
812 while (nodenum < O2NM_MAX_NODES) {
813 if (test_bit(nodenum, dlm->domain_map)) {
814 if (!byte_test_bit(nodenum, query->node_map)) {
815 mlog(0, "disallow join as node %u does not "
816 "have node %u in its nodemap\n",
817 query->node_idx, nodenum);
818 packet.code = JOIN_DISALLOW;
819 goto unlock_respond;
820 }
821 }
822 nodenum++;
823 }
824
825 /* Once the dlm ctxt is marked as leaving then we don't want
826 * to be put in someone's domain map.
827 * Also, explicitly disallow joining at certain troublesome
828 * times (ie. during recovery). */
829 if (dlm && dlm->dlm_state != DLM_CTXT_LEAVING) {
830 int bit = query->node_idx;
831 spin_lock(&dlm->spinlock);
832
833 if (dlm->dlm_state == DLM_CTXT_NEW &&
834 dlm->joining_node == DLM_LOCK_RES_OWNER_UNKNOWN) {
835 /*If this is a brand new context and we
836 * haven't started our join process yet, then
837 * the other node won the race. */
838 packet.code = JOIN_OK_NO_MAP;
839 } else if (dlm->joining_node != DLM_LOCK_RES_OWNER_UNKNOWN) {
840 /* Disallow parallel joins. */
841 packet.code = JOIN_DISALLOW;
842 } else if (dlm->reco.state & DLM_RECO_STATE_ACTIVE) {
843 mlog(0, "node %u trying to join, but recovery "
844 "is ongoing.\n", bit);
845 packet.code = JOIN_DISALLOW;
846 } else if (test_bit(bit, dlm->recovery_map)) {
847 mlog(0, "node %u trying to join, but it "
848 "still needs recovery.\n", bit);
849 packet.code = JOIN_DISALLOW;
850 } else if (test_bit(bit, dlm->domain_map)) {
851 mlog(0, "node %u trying to join, but it "
852 "is still in the domain! needs recovery?\n",
853 bit);
854 packet.code = JOIN_DISALLOW;
855 } else {
856 /* Alright we're fully a part of this domain
857 * so we keep some state as to who's joining
858 * and indicate to him that needs to be fixed
859 * up. */
860
861 /* Make sure we speak compatible locking protocols. */
862 if (dlm_query_join_proto_check("DLM", bit,
863 &dlm->dlm_locking_proto,
864 &query->dlm_proto)) {
865 packet.code = JOIN_PROTOCOL_MISMATCH;
866 } else if (dlm_query_join_proto_check("fs", bit,
867 &dlm->fs_locking_proto,
868 &query->fs_proto)) {
869 packet.code = JOIN_PROTOCOL_MISMATCH;
870 } else {
871 packet.dlm_minor = query->dlm_proto.pv_minor;
872 packet.fs_minor = query->fs_proto.pv_minor;
873 packet.code = JOIN_OK;
874 __dlm_set_joining_node(dlm, query->node_idx);
875 }
876 }
877
878 spin_unlock(&dlm->spinlock);
879 }
880 unlock_respond:
881 spin_unlock(&dlm_domain_lock);
882
883 respond:
884 mlog(0, "We respond with %u\n", packet.code);
885
886 dlm_query_join_packet_to_wire(&packet, &response);
887 return response;
888 }
889
dlm_assert_joined_handler(struct o2net_msg * msg,u32 len,void * data,void ** ret_data)890 static int dlm_assert_joined_handler(struct o2net_msg *msg, u32 len, void *data,
891 void **ret_data)
892 {
893 struct dlm_assert_joined *assert;
894 struct dlm_ctxt *dlm = NULL;
895
896 assert = (struct dlm_assert_joined *) msg->buf;
897
898 mlog(0, "node %u asserts join on domain %s\n", assert->node_idx,
899 assert->domain);
900
901 spin_lock(&dlm_domain_lock);
902 dlm = __dlm_lookup_domain_full(assert->domain, assert->name_len);
903 /* XXX should we consider no dlm ctxt an error? */
904 if (dlm) {
905 spin_lock(&dlm->spinlock);
906
907 /* Alright, this node has officially joined our
908 * domain. Set him in the map and clean up our
909 * leftover join state. */
910 BUG_ON(dlm->joining_node != assert->node_idx);
911 set_bit(assert->node_idx, dlm->domain_map);
912 __dlm_set_joining_node(dlm, DLM_LOCK_RES_OWNER_UNKNOWN);
913
914 printk(KERN_NOTICE "o2dlm: Node %u joins domain %s\n",
915 assert->node_idx, dlm->name);
916 __dlm_print_nodes(dlm);
917
918 /* notify anything attached to the heartbeat events */
919 dlm_hb_event_notify_attached(dlm, assert->node_idx, 1);
920
921 spin_unlock(&dlm->spinlock);
922 }
923 spin_unlock(&dlm_domain_lock);
924
925 return 0;
926 }
927
dlm_match_regions(struct dlm_ctxt * dlm,struct dlm_query_region * qr,char * local,int locallen)928 static int dlm_match_regions(struct dlm_ctxt *dlm,
929 struct dlm_query_region *qr,
930 char *local, int locallen)
931 {
932 char *remote = qr->qr_regions;
933 char *l, *r;
934 int localnr, i, j, foundit;
935 int status = 0;
936
937 if (!o2hb_global_heartbeat_active()) {
938 if (qr->qr_numregions) {
939 mlog(ML_ERROR, "Domain %s: Joining node %d has global "
940 "heartbeat enabled but local node %d does not\n",
941 qr->qr_domain, qr->qr_node, dlm->node_num);
942 status = -EINVAL;
943 }
944 goto bail;
945 }
946
947 if (o2hb_global_heartbeat_active() && !qr->qr_numregions) {
948 mlog(ML_ERROR, "Domain %s: Local node %d has global "
949 "heartbeat enabled but joining node %d does not\n",
950 qr->qr_domain, dlm->node_num, qr->qr_node);
951 status = -EINVAL;
952 goto bail;
953 }
954
955 r = remote;
956 for (i = 0; i < qr->qr_numregions; ++i) {
957 mlog(0, "Region %.*s\n", O2HB_MAX_REGION_NAME_LEN, r);
958 r += O2HB_MAX_REGION_NAME_LEN;
959 }
960
961 localnr = min(O2NM_MAX_REGIONS, locallen/O2HB_MAX_REGION_NAME_LEN);
962 localnr = o2hb_get_all_regions(local, (u8)localnr);
963
964 /* compare local regions with remote */
965 l = local;
966 for (i = 0; i < localnr; ++i) {
967 foundit = 0;
968 r = remote;
969 for (j = 0; j <= qr->qr_numregions; ++j) {
970 if (!memcmp(l, r, O2HB_MAX_REGION_NAME_LEN)) {
971 foundit = 1;
972 break;
973 }
974 r += O2HB_MAX_REGION_NAME_LEN;
975 }
976 if (!foundit) {
977 status = -EINVAL;
978 mlog(ML_ERROR, "Domain %s: Region '%.*s' registered "
979 "in local node %d but not in joining node %d\n",
980 qr->qr_domain, O2HB_MAX_REGION_NAME_LEN, l,
981 dlm->node_num, qr->qr_node);
982 goto bail;
983 }
984 l += O2HB_MAX_REGION_NAME_LEN;
985 }
986
987 /* compare remote with local regions */
988 r = remote;
989 for (i = 0; i < qr->qr_numregions; ++i) {
990 foundit = 0;
991 l = local;
992 for (j = 0; j < localnr; ++j) {
993 if (!memcmp(r, l, O2HB_MAX_REGION_NAME_LEN)) {
994 foundit = 1;
995 break;
996 }
997 l += O2HB_MAX_REGION_NAME_LEN;
998 }
999 if (!foundit) {
1000 status = -EINVAL;
1001 mlog(ML_ERROR, "Domain %s: Region '%.*s' registered "
1002 "in joining node %d but not in local node %d\n",
1003 qr->qr_domain, O2HB_MAX_REGION_NAME_LEN, r,
1004 qr->qr_node, dlm->node_num);
1005 goto bail;
1006 }
1007 r += O2HB_MAX_REGION_NAME_LEN;
1008 }
1009
1010 bail:
1011 return status;
1012 }
1013
dlm_send_regions(struct dlm_ctxt * dlm,unsigned long * node_map)1014 static int dlm_send_regions(struct dlm_ctxt *dlm, unsigned long *node_map)
1015 {
1016 struct dlm_query_region *qr = NULL;
1017 int status, ret = 0, i;
1018 char *p;
1019
1020 if (find_next_bit(node_map, O2NM_MAX_NODES, 0) >= O2NM_MAX_NODES)
1021 goto bail;
1022
1023 qr = kzalloc(sizeof(struct dlm_query_region), GFP_KERNEL);
1024 if (!qr) {
1025 ret = -ENOMEM;
1026 mlog_errno(ret);
1027 goto bail;
1028 }
1029
1030 qr->qr_node = dlm->node_num;
1031 qr->qr_namelen = strlen(dlm->name);
1032 memcpy(qr->qr_domain, dlm->name, qr->qr_namelen);
1033 /* if local hb, the numregions will be zero */
1034 if (o2hb_global_heartbeat_active())
1035 qr->qr_numregions = o2hb_get_all_regions(qr->qr_regions,
1036 O2NM_MAX_REGIONS);
1037
1038 p = qr->qr_regions;
1039 for (i = 0; i < qr->qr_numregions; ++i, p += O2HB_MAX_REGION_NAME_LEN)
1040 mlog(0, "Region %.*s\n", O2HB_MAX_REGION_NAME_LEN, p);
1041
1042 i = -1;
1043 while ((i = find_next_bit(node_map, O2NM_MAX_NODES,
1044 i + 1)) < O2NM_MAX_NODES) {
1045 if (i == dlm->node_num)
1046 continue;
1047
1048 mlog(0, "Sending regions to node %d\n", i);
1049
1050 ret = o2net_send_message(DLM_QUERY_REGION, DLM_MOD_KEY, qr,
1051 sizeof(struct dlm_query_region),
1052 i, &status);
1053 if (ret >= 0)
1054 ret = status;
1055 if (ret) {
1056 mlog(ML_ERROR, "Region mismatch %d, node %d\n",
1057 ret, i);
1058 break;
1059 }
1060 }
1061
1062 bail:
1063 kfree(qr);
1064 return ret;
1065 }
1066
dlm_query_region_handler(struct o2net_msg * msg,u32 len,void * data,void ** ret_data)1067 static int dlm_query_region_handler(struct o2net_msg *msg, u32 len,
1068 void *data, void **ret_data)
1069 {
1070 struct dlm_query_region *qr;
1071 struct dlm_ctxt *dlm = NULL;
1072 char *local = NULL;
1073 int status = 0;
1074 int locked = 0;
1075
1076 qr = (struct dlm_query_region *) msg->buf;
1077
1078 mlog(0, "Node %u queries hb regions on domain %s\n", qr->qr_node,
1079 qr->qr_domain);
1080
1081 /* buffer used in dlm_mast_regions() */
1082 local = kmalloc(sizeof(qr->qr_regions), GFP_KERNEL);
1083 if (!local) {
1084 status = -ENOMEM;
1085 goto bail;
1086 }
1087
1088 status = -EINVAL;
1089
1090 spin_lock(&dlm_domain_lock);
1091 dlm = __dlm_lookup_domain_full(qr->qr_domain, qr->qr_namelen);
1092 if (!dlm) {
1093 mlog(ML_ERROR, "Node %d queried hb regions on domain %s "
1094 "before join domain\n", qr->qr_node, qr->qr_domain);
1095 goto bail;
1096 }
1097
1098 spin_lock(&dlm->spinlock);
1099 locked = 1;
1100 if (dlm->joining_node != qr->qr_node) {
1101 mlog(ML_ERROR, "Node %d queried hb regions on domain %s "
1102 "but joining node is %d\n", qr->qr_node, qr->qr_domain,
1103 dlm->joining_node);
1104 goto bail;
1105 }
1106
1107 /* Support for global heartbeat was added in 1.1 */
1108 if (dlm->dlm_locking_proto.pv_major == 1 &&
1109 dlm->dlm_locking_proto.pv_minor == 0) {
1110 mlog(ML_ERROR, "Node %d queried hb regions on domain %s "
1111 "but active dlm protocol is %d.%d\n", qr->qr_node,
1112 qr->qr_domain, dlm->dlm_locking_proto.pv_major,
1113 dlm->dlm_locking_proto.pv_minor);
1114 goto bail;
1115 }
1116
1117 status = dlm_match_regions(dlm, qr, local, sizeof(qr->qr_regions));
1118
1119 bail:
1120 if (locked)
1121 spin_unlock(&dlm->spinlock);
1122 spin_unlock(&dlm_domain_lock);
1123
1124 kfree(local);
1125
1126 return status;
1127 }
1128
dlm_match_nodes(struct dlm_ctxt * dlm,struct dlm_query_nodeinfo * qn)1129 static int dlm_match_nodes(struct dlm_ctxt *dlm, struct dlm_query_nodeinfo *qn)
1130 {
1131 struct o2nm_node *local;
1132 struct dlm_node_info *remote;
1133 int i, j;
1134 int status = 0;
1135
1136 for (j = 0; j < qn->qn_numnodes; ++j)
1137 mlog(0, "Node %3d, %pI4:%u\n", qn->qn_nodes[j].ni_nodenum,
1138 &(qn->qn_nodes[j].ni_ipv4_address),
1139 ntohs(qn->qn_nodes[j].ni_ipv4_port));
1140
1141 for (i = 0; i < O2NM_MAX_NODES && !status; ++i) {
1142 local = o2nm_get_node_by_num(i);
1143 remote = NULL;
1144 for (j = 0; j < qn->qn_numnodes; ++j) {
1145 if (qn->qn_nodes[j].ni_nodenum == i) {
1146 remote = &(qn->qn_nodes[j]);
1147 break;
1148 }
1149 }
1150
1151 if (!local && !remote)
1152 continue;
1153
1154 if ((local && !remote) || (!local && remote))
1155 status = -EINVAL;
1156
1157 if (!status &&
1158 ((remote->ni_nodenum != local->nd_num) ||
1159 (remote->ni_ipv4_port != local->nd_ipv4_port) ||
1160 (remote->ni_ipv4_address != local->nd_ipv4_address)))
1161 status = -EINVAL;
1162
1163 if (status) {
1164 if (remote && !local)
1165 mlog(ML_ERROR, "Domain %s: Node %d (%pI4:%u) "
1166 "registered in joining node %d but not in "
1167 "local node %d\n", qn->qn_domain,
1168 remote->ni_nodenum,
1169 &(remote->ni_ipv4_address),
1170 ntohs(remote->ni_ipv4_port),
1171 qn->qn_nodenum, dlm->node_num);
1172 if (local && !remote)
1173 mlog(ML_ERROR, "Domain %s: Node %d (%pI4:%u) "
1174 "registered in local node %d but not in "
1175 "joining node %d\n", qn->qn_domain,
1176 local->nd_num, &(local->nd_ipv4_address),
1177 ntohs(local->nd_ipv4_port),
1178 dlm->node_num, qn->qn_nodenum);
1179 BUG_ON((!local && !remote));
1180 }
1181
1182 if (local)
1183 o2nm_node_put(local);
1184 }
1185
1186 return status;
1187 }
1188
dlm_send_nodeinfo(struct dlm_ctxt * dlm,unsigned long * node_map)1189 static int dlm_send_nodeinfo(struct dlm_ctxt *dlm, unsigned long *node_map)
1190 {
1191 struct dlm_query_nodeinfo *qn = NULL;
1192 struct o2nm_node *node;
1193 int ret = 0, status, count, i;
1194
1195 if (find_next_bit(node_map, O2NM_MAX_NODES, 0) >= O2NM_MAX_NODES)
1196 goto bail;
1197
1198 qn = kzalloc(sizeof(struct dlm_query_nodeinfo), GFP_KERNEL);
1199 if (!qn) {
1200 ret = -ENOMEM;
1201 mlog_errno(ret);
1202 goto bail;
1203 }
1204
1205 for (i = 0, count = 0; i < O2NM_MAX_NODES; ++i) {
1206 node = o2nm_get_node_by_num(i);
1207 if (!node)
1208 continue;
1209 qn->qn_nodes[count].ni_nodenum = node->nd_num;
1210 qn->qn_nodes[count].ni_ipv4_port = node->nd_ipv4_port;
1211 qn->qn_nodes[count].ni_ipv4_address = node->nd_ipv4_address;
1212 mlog(0, "Node %3d, %pI4:%u\n", node->nd_num,
1213 &(node->nd_ipv4_address), ntohs(node->nd_ipv4_port));
1214 ++count;
1215 o2nm_node_put(node);
1216 }
1217
1218 qn->qn_nodenum = dlm->node_num;
1219 qn->qn_numnodes = count;
1220 qn->qn_namelen = strlen(dlm->name);
1221 memcpy(qn->qn_domain, dlm->name, qn->qn_namelen);
1222
1223 i = -1;
1224 while ((i = find_next_bit(node_map, O2NM_MAX_NODES,
1225 i + 1)) < O2NM_MAX_NODES) {
1226 if (i == dlm->node_num)
1227 continue;
1228
1229 mlog(0, "Sending nodeinfo to node %d\n", i);
1230
1231 ret = o2net_send_message(DLM_QUERY_NODEINFO, DLM_MOD_KEY,
1232 qn, sizeof(struct dlm_query_nodeinfo),
1233 i, &status);
1234 if (ret >= 0)
1235 ret = status;
1236 if (ret) {
1237 mlog(ML_ERROR, "node mismatch %d, node %d\n", ret, i);
1238 break;
1239 }
1240 }
1241
1242 bail:
1243 kfree(qn);
1244 return ret;
1245 }
1246
dlm_query_nodeinfo_handler(struct o2net_msg * msg,u32 len,void * data,void ** ret_data)1247 static int dlm_query_nodeinfo_handler(struct o2net_msg *msg, u32 len,
1248 void *data, void **ret_data)
1249 {
1250 struct dlm_query_nodeinfo *qn;
1251 struct dlm_ctxt *dlm = NULL;
1252 int locked = 0, status = -EINVAL;
1253
1254 qn = (struct dlm_query_nodeinfo *) msg->buf;
1255
1256 mlog(0, "Node %u queries nodes on domain %s\n", qn->qn_nodenum,
1257 qn->qn_domain);
1258
1259 spin_lock(&dlm_domain_lock);
1260 dlm = __dlm_lookup_domain_full(qn->qn_domain, qn->qn_namelen);
1261 if (!dlm) {
1262 mlog(ML_ERROR, "Node %d queried nodes on domain %s before "
1263 "join domain\n", qn->qn_nodenum, qn->qn_domain);
1264 goto bail;
1265 }
1266
1267 spin_lock(&dlm->spinlock);
1268 locked = 1;
1269 if (dlm->joining_node != qn->qn_nodenum) {
1270 mlog(ML_ERROR, "Node %d queried nodes on domain %s but "
1271 "joining node is %d\n", qn->qn_nodenum, qn->qn_domain,
1272 dlm->joining_node);
1273 goto bail;
1274 }
1275
1276 /* Support for node query was added in 1.1 */
1277 if (dlm->dlm_locking_proto.pv_major == 1 &&
1278 dlm->dlm_locking_proto.pv_minor == 0) {
1279 mlog(ML_ERROR, "Node %d queried nodes on domain %s "
1280 "but active dlm protocol is %d.%d\n", qn->qn_nodenum,
1281 qn->qn_domain, dlm->dlm_locking_proto.pv_major,
1282 dlm->dlm_locking_proto.pv_minor);
1283 goto bail;
1284 }
1285
1286 status = dlm_match_nodes(dlm, qn);
1287
1288 bail:
1289 if (locked)
1290 spin_unlock(&dlm->spinlock);
1291 spin_unlock(&dlm_domain_lock);
1292
1293 return status;
1294 }
1295
dlm_cancel_join_handler(struct o2net_msg * msg,u32 len,void * data,void ** ret_data)1296 static int dlm_cancel_join_handler(struct o2net_msg *msg, u32 len, void *data,
1297 void **ret_data)
1298 {
1299 struct dlm_cancel_join *cancel;
1300 struct dlm_ctxt *dlm = NULL;
1301
1302 cancel = (struct dlm_cancel_join *) msg->buf;
1303
1304 mlog(0, "node %u cancels join on domain %s\n", cancel->node_idx,
1305 cancel->domain);
1306
1307 spin_lock(&dlm_domain_lock);
1308 dlm = __dlm_lookup_domain_full(cancel->domain, cancel->name_len);
1309
1310 if (dlm) {
1311 spin_lock(&dlm->spinlock);
1312
1313 /* Yikes, this guy wants to cancel his join. No
1314 * problem, we simply cleanup our join state. */
1315 BUG_ON(dlm->joining_node != cancel->node_idx);
1316 __dlm_set_joining_node(dlm, DLM_LOCK_RES_OWNER_UNKNOWN);
1317
1318 spin_unlock(&dlm->spinlock);
1319 }
1320 spin_unlock(&dlm_domain_lock);
1321
1322 return 0;
1323 }
1324
dlm_send_one_join_cancel(struct dlm_ctxt * dlm,unsigned int node)1325 static int dlm_send_one_join_cancel(struct dlm_ctxt *dlm,
1326 unsigned int node)
1327 {
1328 int status;
1329 struct dlm_cancel_join cancel_msg;
1330
1331 memset(&cancel_msg, 0, sizeof(cancel_msg));
1332 cancel_msg.node_idx = dlm->node_num;
1333 cancel_msg.name_len = strlen(dlm->name);
1334 memcpy(cancel_msg.domain, dlm->name, cancel_msg.name_len);
1335
1336 status = o2net_send_message(DLM_CANCEL_JOIN_MSG, DLM_MOD_KEY,
1337 &cancel_msg, sizeof(cancel_msg), node,
1338 NULL);
1339 if (status < 0) {
1340 mlog(ML_ERROR, "Error %d when sending message %u (key 0x%x) to "
1341 "node %u\n", status, DLM_CANCEL_JOIN_MSG, DLM_MOD_KEY,
1342 node);
1343 goto bail;
1344 }
1345
1346 bail:
1347 return status;
1348 }
1349
1350 /* map_size should be in bytes. */
dlm_send_join_cancels(struct dlm_ctxt * dlm,unsigned long * node_map,unsigned int map_size)1351 static int dlm_send_join_cancels(struct dlm_ctxt *dlm,
1352 unsigned long *node_map,
1353 unsigned int map_size)
1354 {
1355 int status, tmpstat;
1356 unsigned int node;
1357
1358 if (map_size != (BITS_TO_LONGS(O2NM_MAX_NODES) *
1359 sizeof(unsigned long))) {
1360 mlog(ML_ERROR,
1361 "map_size %u != BITS_TO_LONGS(O2NM_MAX_NODES) %u\n",
1362 map_size, (unsigned)BITS_TO_LONGS(O2NM_MAX_NODES));
1363 return -EINVAL;
1364 }
1365
1366 status = 0;
1367 node = -1;
1368 while ((node = find_next_bit(node_map, O2NM_MAX_NODES,
1369 node + 1)) < O2NM_MAX_NODES) {
1370 if (node == dlm->node_num)
1371 continue;
1372
1373 tmpstat = dlm_send_one_join_cancel(dlm, node);
1374 if (tmpstat) {
1375 mlog(ML_ERROR, "Error return %d cancelling join on "
1376 "node %d\n", tmpstat, node);
1377 if (!status)
1378 status = tmpstat;
1379 }
1380 }
1381
1382 if (status)
1383 mlog_errno(status);
1384 return status;
1385 }
1386
dlm_request_join(struct dlm_ctxt * dlm,int node,enum dlm_query_join_response_code * response)1387 static int dlm_request_join(struct dlm_ctxt *dlm,
1388 int node,
1389 enum dlm_query_join_response_code *response)
1390 {
1391 int status;
1392 struct dlm_query_join_request join_msg;
1393 struct dlm_query_join_packet packet;
1394 u32 join_resp;
1395
1396 mlog(0, "querying node %d\n", node);
1397
1398 memset(&join_msg, 0, sizeof(join_msg));
1399 join_msg.node_idx = dlm->node_num;
1400 join_msg.name_len = strlen(dlm->name);
1401 memcpy(join_msg.domain, dlm->name, join_msg.name_len);
1402 join_msg.dlm_proto = dlm->dlm_locking_proto;
1403 join_msg.fs_proto = dlm->fs_locking_proto;
1404
1405 /* copy live node map to join message */
1406 byte_copymap(join_msg.node_map, dlm->live_nodes_map, O2NM_MAX_NODES);
1407
1408 status = o2net_send_message(DLM_QUERY_JOIN_MSG, DLM_MOD_KEY, &join_msg,
1409 sizeof(join_msg), node, &join_resp);
1410 if (status < 0 && status != -ENOPROTOOPT) {
1411 mlog(ML_ERROR, "Error %d when sending message %u (key 0x%x) to "
1412 "node %u\n", status, DLM_QUERY_JOIN_MSG, DLM_MOD_KEY,
1413 node);
1414 goto bail;
1415 }
1416 dlm_query_join_wire_to_packet(join_resp, &packet);
1417
1418 /* -ENOPROTOOPT from the net code means the other side isn't
1419 listening for our message type -- that's fine, it means
1420 his dlm isn't up, so we can consider him a 'yes' but not
1421 joined into the domain. */
1422 if (status == -ENOPROTOOPT) {
1423 status = 0;
1424 *response = JOIN_OK_NO_MAP;
1425 } else if (packet.code == JOIN_DISALLOW ||
1426 packet.code == JOIN_OK_NO_MAP) {
1427 *response = packet.code;
1428 } else if (packet.code == JOIN_PROTOCOL_MISMATCH) {
1429 mlog(ML_NOTICE,
1430 "This node requested DLM locking protocol %u.%u and "
1431 "filesystem locking protocol %u.%u. At least one of "
1432 "the protocol versions on node %d is not compatible, "
1433 "disconnecting\n",
1434 dlm->dlm_locking_proto.pv_major,
1435 dlm->dlm_locking_proto.pv_minor,
1436 dlm->fs_locking_proto.pv_major,
1437 dlm->fs_locking_proto.pv_minor,
1438 node);
1439 status = -EPROTO;
1440 *response = packet.code;
1441 } else if (packet.code == JOIN_OK) {
1442 *response = packet.code;
1443 /* Use the same locking protocol as the remote node */
1444 dlm->dlm_locking_proto.pv_minor = packet.dlm_minor;
1445 dlm->fs_locking_proto.pv_minor = packet.fs_minor;
1446 mlog(0,
1447 "Node %d responds JOIN_OK with DLM locking protocol "
1448 "%u.%u and fs locking protocol %u.%u\n",
1449 node,
1450 dlm->dlm_locking_proto.pv_major,
1451 dlm->dlm_locking_proto.pv_minor,
1452 dlm->fs_locking_proto.pv_major,
1453 dlm->fs_locking_proto.pv_minor);
1454 } else {
1455 status = -EINVAL;
1456 mlog(ML_ERROR, "invalid response %d from node %u\n",
1457 packet.code, node);
1458 }
1459
1460 mlog(0, "status %d, node %d response is %d\n", status, node,
1461 *response);
1462
1463 bail:
1464 return status;
1465 }
1466
dlm_send_one_join_assert(struct dlm_ctxt * dlm,unsigned int node)1467 static int dlm_send_one_join_assert(struct dlm_ctxt *dlm,
1468 unsigned int node)
1469 {
1470 int status;
1471 struct dlm_assert_joined assert_msg;
1472
1473 mlog(0, "Sending join assert to node %u\n", node);
1474
1475 memset(&assert_msg, 0, sizeof(assert_msg));
1476 assert_msg.node_idx = dlm->node_num;
1477 assert_msg.name_len = strlen(dlm->name);
1478 memcpy(assert_msg.domain, dlm->name, assert_msg.name_len);
1479
1480 status = o2net_send_message(DLM_ASSERT_JOINED_MSG, DLM_MOD_KEY,
1481 &assert_msg, sizeof(assert_msg), node,
1482 NULL);
1483 if (status < 0)
1484 mlog(ML_ERROR, "Error %d when sending message %u (key 0x%x) to "
1485 "node %u\n", status, DLM_ASSERT_JOINED_MSG, DLM_MOD_KEY,
1486 node);
1487
1488 return status;
1489 }
1490
dlm_send_join_asserts(struct dlm_ctxt * dlm,unsigned long * node_map)1491 static void dlm_send_join_asserts(struct dlm_ctxt *dlm,
1492 unsigned long *node_map)
1493 {
1494 int status, node, live;
1495
1496 status = 0;
1497 node = -1;
1498 while ((node = find_next_bit(node_map, O2NM_MAX_NODES,
1499 node + 1)) < O2NM_MAX_NODES) {
1500 if (node == dlm->node_num)
1501 continue;
1502
1503 do {
1504 /* It is very important that this message be
1505 * received so we spin until either the node
1506 * has died or it gets the message. */
1507 status = dlm_send_one_join_assert(dlm, node);
1508
1509 spin_lock(&dlm->spinlock);
1510 live = test_bit(node, dlm->live_nodes_map);
1511 spin_unlock(&dlm->spinlock);
1512
1513 if (status) {
1514 mlog(ML_ERROR, "Error return %d asserting "
1515 "join on node %d\n", status, node);
1516
1517 /* give us some time between errors... */
1518 if (live)
1519 msleep(DLM_DOMAIN_BACKOFF_MS);
1520 }
1521 } while (status && live);
1522 }
1523 }
1524
1525 struct domain_join_ctxt {
1526 unsigned long live_map[BITS_TO_LONGS(O2NM_MAX_NODES)];
1527 unsigned long yes_resp_map[BITS_TO_LONGS(O2NM_MAX_NODES)];
1528 };
1529
dlm_should_restart_join(struct dlm_ctxt * dlm,struct domain_join_ctxt * ctxt,enum dlm_query_join_response_code response)1530 static int dlm_should_restart_join(struct dlm_ctxt *dlm,
1531 struct domain_join_ctxt *ctxt,
1532 enum dlm_query_join_response_code response)
1533 {
1534 int ret;
1535
1536 if (response == JOIN_DISALLOW) {
1537 mlog(0, "Latest response of disallow -- should restart\n");
1538 return 1;
1539 }
1540
1541 spin_lock(&dlm->spinlock);
1542 /* For now, we restart the process if the node maps have
1543 * changed at all */
1544 ret = memcmp(ctxt->live_map, dlm->live_nodes_map,
1545 sizeof(dlm->live_nodes_map));
1546 spin_unlock(&dlm->spinlock);
1547
1548 if (ret)
1549 mlog(0, "Node maps changed -- should restart\n");
1550
1551 return ret;
1552 }
1553
dlm_try_to_join_domain(struct dlm_ctxt * dlm)1554 static int dlm_try_to_join_domain(struct dlm_ctxt *dlm)
1555 {
1556 int status = 0, tmpstat, node;
1557 struct domain_join_ctxt *ctxt;
1558 enum dlm_query_join_response_code response = JOIN_DISALLOW;
1559
1560 mlog(0, "%p", dlm);
1561
1562 ctxt = kzalloc(sizeof(*ctxt), GFP_KERNEL);
1563 if (!ctxt) {
1564 status = -ENOMEM;
1565 mlog_errno(status);
1566 goto bail;
1567 }
1568
1569 /* group sem locking should work for us here -- we're already
1570 * registered for heartbeat events so filling this should be
1571 * atomic wrt getting those handlers called. */
1572 o2hb_fill_node_map(dlm->live_nodes_map, sizeof(dlm->live_nodes_map));
1573
1574 spin_lock(&dlm->spinlock);
1575 memcpy(ctxt->live_map, dlm->live_nodes_map, sizeof(ctxt->live_map));
1576
1577 __dlm_set_joining_node(dlm, dlm->node_num);
1578
1579 spin_unlock(&dlm->spinlock);
1580
1581 node = -1;
1582 while ((node = find_next_bit(ctxt->live_map, O2NM_MAX_NODES,
1583 node + 1)) < O2NM_MAX_NODES) {
1584 if (node == dlm->node_num)
1585 continue;
1586
1587 status = dlm_request_join(dlm, node, &response);
1588 if (status < 0) {
1589 mlog_errno(status);
1590 goto bail;
1591 }
1592
1593 /* Ok, either we got a response or the node doesn't have a
1594 * dlm up. */
1595 if (response == JOIN_OK)
1596 set_bit(node, ctxt->yes_resp_map);
1597
1598 if (dlm_should_restart_join(dlm, ctxt, response)) {
1599 status = -EAGAIN;
1600 goto bail;
1601 }
1602 }
1603
1604 mlog(0, "Yay, done querying nodes!\n");
1605
1606 /* Yay, everyone agree's we can join the domain. My domain is
1607 * comprised of all nodes who were put in the
1608 * yes_resp_map. Copy that into our domain map and send a join
1609 * assert message to clean up everyone elses state. */
1610 spin_lock(&dlm->spinlock);
1611 memcpy(dlm->domain_map, ctxt->yes_resp_map,
1612 sizeof(ctxt->yes_resp_map));
1613 set_bit(dlm->node_num, dlm->domain_map);
1614 spin_unlock(&dlm->spinlock);
1615
1616 /* Support for global heartbeat and node info was added in 1.1 */
1617 if (dlm->dlm_locking_proto.pv_major > 1 ||
1618 dlm->dlm_locking_proto.pv_minor > 0) {
1619 status = dlm_send_nodeinfo(dlm, ctxt->yes_resp_map);
1620 if (status) {
1621 mlog_errno(status);
1622 goto bail;
1623 }
1624 status = dlm_send_regions(dlm, ctxt->yes_resp_map);
1625 if (status) {
1626 mlog_errno(status);
1627 goto bail;
1628 }
1629 }
1630
1631 dlm_send_join_asserts(dlm, ctxt->yes_resp_map);
1632
1633 /* Joined state *must* be set before the joining node
1634 * information, otherwise the query_join handler may read no
1635 * current joiner but a state of NEW and tell joining nodes
1636 * we're not in the domain. */
1637 spin_lock(&dlm_domain_lock);
1638 dlm->dlm_state = DLM_CTXT_JOINED;
1639 dlm->num_joins++;
1640 spin_unlock(&dlm_domain_lock);
1641
1642 bail:
1643 spin_lock(&dlm->spinlock);
1644 __dlm_set_joining_node(dlm, DLM_LOCK_RES_OWNER_UNKNOWN);
1645 if (!status)
1646 __dlm_print_nodes(dlm);
1647 spin_unlock(&dlm->spinlock);
1648
1649 if (ctxt) {
1650 /* Do we need to send a cancel message to any nodes? */
1651 if (status < 0) {
1652 tmpstat = dlm_send_join_cancels(dlm,
1653 ctxt->yes_resp_map,
1654 sizeof(ctxt->yes_resp_map));
1655 if (tmpstat < 0)
1656 mlog_errno(tmpstat);
1657 }
1658 kfree(ctxt);
1659 }
1660
1661 mlog(0, "returning %d\n", status);
1662 return status;
1663 }
1664
dlm_unregister_domain_handlers(struct dlm_ctxt * dlm)1665 static void dlm_unregister_domain_handlers(struct dlm_ctxt *dlm)
1666 {
1667 o2hb_unregister_callback(dlm->name, &dlm->dlm_hb_up);
1668 o2hb_unregister_callback(dlm->name, &dlm->dlm_hb_down);
1669 o2net_unregister_handler_list(&dlm->dlm_domain_handlers);
1670 }
1671
dlm_register_domain_handlers(struct dlm_ctxt * dlm)1672 static int dlm_register_domain_handlers(struct dlm_ctxt *dlm)
1673 {
1674 int status;
1675
1676 mlog(0, "registering handlers.\n");
1677
1678 o2hb_setup_callback(&dlm->dlm_hb_down, O2HB_NODE_DOWN_CB,
1679 dlm_hb_node_down_cb, dlm, DLM_HB_NODE_DOWN_PRI);
1680 status = o2hb_register_callback(dlm->name, &dlm->dlm_hb_down);
1681 if (status)
1682 goto bail;
1683
1684 o2hb_setup_callback(&dlm->dlm_hb_up, O2HB_NODE_UP_CB,
1685 dlm_hb_node_up_cb, dlm, DLM_HB_NODE_UP_PRI);
1686 status = o2hb_register_callback(dlm->name, &dlm->dlm_hb_up);
1687 if (status)
1688 goto bail;
1689
1690 status = o2net_register_handler(DLM_MASTER_REQUEST_MSG, dlm->key,
1691 sizeof(struct dlm_master_request),
1692 dlm_master_request_handler,
1693 dlm, NULL, &dlm->dlm_domain_handlers);
1694 if (status)
1695 goto bail;
1696
1697 status = o2net_register_handler(DLM_ASSERT_MASTER_MSG, dlm->key,
1698 sizeof(struct dlm_assert_master),
1699 dlm_assert_master_handler,
1700 dlm, dlm_assert_master_post_handler,
1701 &dlm->dlm_domain_handlers);
1702 if (status)
1703 goto bail;
1704
1705 status = o2net_register_handler(DLM_CREATE_LOCK_MSG, dlm->key,
1706 sizeof(struct dlm_create_lock),
1707 dlm_create_lock_handler,
1708 dlm, NULL, &dlm->dlm_domain_handlers);
1709 if (status)
1710 goto bail;
1711
1712 status = o2net_register_handler(DLM_CONVERT_LOCK_MSG, dlm->key,
1713 DLM_CONVERT_LOCK_MAX_LEN,
1714 dlm_convert_lock_handler,
1715 dlm, NULL, &dlm->dlm_domain_handlers);
1716 if (status)
1717 goto bail;
1718
1719 status = o2net_register_handler(DLM_UNLOCK_LOCK_MSG, dlm->key,
1720 DLM_UNLOCK_LOCK_MAX_LEN,
1721 dlm_unlock_lock_handler,
1722 dlm, NULL, &dlm->dlm_domain_handlers);
1723 if (status)
1724 goto bail;
1725
1726 status = o2net_register_handler(DLM_PROXY_AST_MSG, dlm->key,
1727 DLM_PROXY_AST_MAX_LEN,
1728 dlm_proxy_ast_handler,
1729 dlm, NULL, &dlm->dlm_domain_handlers);
1730 if (status)
1731 goto bail;
1732
1733 status = o2net_register_handler(DLM_EXIT_DOMAIN_MSG, dlm->key,
1734 sizeof(struct dlm_exit_domain),
1735 dlm_exit_domain_handler,
1736 dlm, NULL, &dlm->dlm_domain_handlers);
1737 if (status)
1738 goto bail;
1739
1740 status = o2net_register_handler(DLM_DEREF_LOCKRES_MSG, dlm->key,
1741 sizeof(struct dlm_deref_lockres),
1742 dlm_deref_lockres_handler,
1743 dlm, NULL, &dlm->dlm_domain_handlers);
1744 if (status)
1745 goto bail;
1746
1747 status = o2net_register_handler(DLM_MIGRATE_REQUEST_MSG, dlm->key,
1748 sizeof(struct dlm_migrate_request),
1749 dlm_migrate_request_handler,
1750 dlm, NULL, &dlm->dlm_domain_handlers);
1751 if (status)
1752 goto bail;
1753
1754 status = o2net_register_handler(DLM_MIG_LOCKRES_MSG, dlm->key,
1755 DLM_MIG_LOCKRES_MAX_LEN,
1756 dlm_mig_lockres_handler,
1757 dlm, NULL, &dlm->dlm_domain_handlers);
1758 if (status)
1759 goto bail;
1760
1761 status = o2net_register_handler(DLM_MASTER_REQUERY_MSG, dlm->key,
1762 sizeof(struct dlm_master_requery),
1763 dlm_master_requery_handler,
1764 dlm, NULL, &dlm->dlm_domain_handlers);
1765 if (status)
1766 goto bail;
1767
1768 status = o2net_register_handler(DLM_LOCK_REQUEST_MSG, dlm->key,
1769 sizeof(struct dlm_lock_request),
1770 dlm_request_all_locks_handler,
1771 dlm, NULL, &dlm->dlm_domain_handlers);
1772 if (status)
1773 goto bail;
1774
1775 status = o2net_register_handler(DLM_RECO_DATA_DONE_MSG, dlm->key,
1776 sizeof(struct dlm_reco_data_done),
1777 dlm_reco_data_done_handler,
1778 dlm, NULL, &dlm->dlm_domain_handlers);
1779 if (status)
1780 goto bail;
1781
1782 status = o2net_register_handler(DLM_BEGIN_RECO_MSG, dlm->key,
1783 sizeof(struct dlm_begin_reco),
1784 dlm_begin_reco_handler,
1785 dlm, NULL, &dlm->dlm_domain_handlers);
1786 if (status)
1787 goto bail;
1788
1789 status = o2net_register_handler(DLM_FINALIZE_RECO_MSG, dlm->key,
1790 sizeof(struct dlm_finalize_reco),
1791 dlm_finalize_reco_handler,
1792 dlm, NULL, &dlm->dlm_domain_handlers);
1793 if (status)
1794 goto bail;
1795
1796 bail:
1797 if (status)
1798 dlm_unregister_domain_handlers(dlm);
1799
1800 return status;
1801 }
1802
dlm_join_domain(struct dlm_ctxt * dlm)1803 static int dlm_join_domain(struct dlm_ctxt *dlm)
1804 {
1805 int status;
1806 unsigned int backoff;
1807 unsigned int total_backoff = 0;
1808
1809 BUG_ON(!dlm);
1810
1811 mlog(0, "Join domain %s\n", dlm->name);
1812
1813 status = dlm_register_domain_handlers(dlm);
1814 if (status) {
1815 mlog_errno(status);
1816 goto bail;
1817 }
1818
1819 status = dlm_debug_init(dlm);
1820 if (status < 0) {
1821 mlog_errno(status);
1822 goto bail;
1823 }
1824
1825 status = dlm_launch_thread(dlm);
1826 if (status < 0) {
1827 mlog_errno(status);
1828 goto bail;
1829 }
1830
1831 status = dlm_launch_recovery_thread(dlm);
1832 if (status < 0) {
1833 mlog_errno(status);
1834 goto bail;
1835 }
1836
1837 dlm->dlm_worker = create_singlethread_workqueue("dlm_wq");
1838 if (!dlm->dlm_worker) {
1839 status = -ENOMEM;
1840 mlog_errno(status);
1841 goto bail;
1842 }
1843
1844 do {
1845 status = dlm_try_to_join_domain(dlm);
1846
1847 /* If we're racing another node to the join, then we
1848 * need to back off temporarily and let them
1849 * complete. */
1850 #define DLM_JOIN_TIMEOUT_MSECS 90000
1851 if (status == -EAGAIN) {
1852 if (signal_pending(current)) {
1853 status = -ERESTARTSYS;
1854 goto bail;
1855 }
1856
1857 if (total_backoff >
1858 msecs_to_jiffies(DLM_JOIN_TIMEOUT_MSECS)) {
1859 status = -ERESTARTSYS;
1860 mlog(ML_NOTICE, "Timed out joining dlm domain "
1861 "%s after %u msecs\n", dlm->name,
1862 jiffies_to_msecs(total_backoff));
1863 goto bail;
1864 }
1865
1866 /*
1867 * <chip> After you!
1868 * <dale> No, after you!
1869 * <chip> I insist!
1870 * <dale> But you first!
1871 * ...
1872 */
1873 backoff = (unsigned int)(jiffies & 0x3);
1874 backoff *= DLM_DOMAIN_BACKOFF_MS;
1875 total_backoff += backoff;
1876 mlog(0, "backoff %d\n", backoff);
1877 msleep(backoff);
1878 }
1879 } while (status == -EAGAIN);
1880
1881 if (status < 0) {
1882 mlog_errno(status);
1883 goto bail;
1884 }
1885
1886 status = 0;
1887 bail:
1888 wake_up(&dlm_domain_events);
1889
1890 if (status) {
1891 dlm_unregister_domain_handlers(dlm);
1892 dlm_debug_shutdown(dlm);
1893 dlm_complete_thread(dlm);
1894 dlm_complete_recovery_thread(dlm);
1895 dlm_destroy_dlm_worker(dlm);
1896 }
1897
1898 return status;
1899 }
1900
dlm_alloc_ctxt(const char * domain,u32 key)1901 static struct dlm_ctxt *dlm_alloc_ctxt(const char *domain,
1902 u32 key)
1903 {
1904 int i;
1905 int ret;
1906 struct dlm_ctxt *dlm = NULL;
1907
1908 dlm = kzalloc(sizeof(*dlm), GFP_KERNEL);
1909 if (!dlm) {
1910 mlog_errno(-ENOMEM);
1911 goto leave;
1912 }
1913
1914 dlm->name = kstrdup(domain, GFP_KERNEL);
1915 if (dlm->name == NULL) {
1916 mlog_errno(-ENOMEM);
1917 kfree(dlm);
1918 dlm = NULL;
1919 goto leave;
1920 }
1921
1922 dlm->lockres_hash = (struct hlist_head **)dlm_alloc_pagevec(DLM_HASH_PAGES);
1923 if (!dlm->lockres_hash) {
1924 mlog_errno(-ENOMEM);
1925 kfree(dlm->name);
1926 kfree(dlm);
1927 dlm = NULL;
1928 goto leave;
1929 }
1930
1931 for (i = 0; i < DLM_HASH_BUCKETS; i++)
1932 INIT_HLIST_HEAD(dlm_lockres_hash(dlm, i));
1933
1934 dlm->master_hash = (struct hlist_head **)
1935 dlm_alloc_pagevec(DLM_HASH_PAGES);
1936 if (!dlm->master_hash) {
1937 mlog_errno(-ENOMEM);
1938 dlm_free_pagevec((void **)dlm->lockres_hash, DLM_HASH_PAGES);
1939 kfree(dlm->name);
1940 kfree(dlm);
1941 dlm = NULL;
1942 goto leave;
1943 }
1944
1945 for (i = 0; i < DLM_HASH_BUCKETS; i++)
1946 INIT_HLIST_HEAD(dlm_master_hash(dlm, i));
1947
1948 dlm->key = key;
1949 dlm->node_num = o2nm_this_node();
1950
1951 ret = dlm_create_debugfs_subroot(dlm);
1952 if (ret < 0) {
1953 dlm_free_pagevec((void **)dlm->master_hash, DLM_HASH_PAGES);
1954 dlm_free_pagevec((void **)dlm->lockres_hash, DLM_HASH_PAGES);
1955 kfree(dlm->name);
1956 kfree(dlm);
1957 dlm = NULL;
1958 goto leave;
1959 }
1960
1961 spin_lock_init(&dlm->spinlock);
1962 spin_lock_init(&dlm->master_lock);
1963 spin_lock_init(&dlm->ast_lock);
1964 spin_lock_init(&dlm->track_lock);
1965 INIT_LIST_HEAD(&dlm->list);
1966 INIT_LIST_HEAD(&dlm->dirty_list);
1967 INIT_LIST_HEAD(&dlm->reco.resources);
1968 INIT_LIST_HEAD(&dlm->reco.received);
1969 INIT_LIST_HEAD(&dlm->reco.node_data);
1970 INIT_LIST_HEAD(&dlm->purge_list);
1971 INIT_LIST_HEAD(&dlm->dlm_domain_handlers);
1972 INIT_LIST_HEAD(&dlm->tracking_list);
1973 dlm->reco.state = 0;
1974
1975 INIT_LIST_HEAD(&dlm->pending_asts);
1976 INIT_LIST_HEAD(&dlm->pending_basts);
1977
1978 mlog(0, "dlm->recovery_map=%p, &(dlm->recovery_map[0])=%p\n",
1979 dlm->recovery_map, &(dlm->recovery_map[0]));
1980
1981 memset(dlm->recovery_map, 0, sizeof(dlm->recovery_map));
1982 memset(dlm->live_nodes_map, 0, sizeof(dlm->live_nodes_map));
1983 memset(dlm->domain_map, 0, sizeof(dlm->domain_map));
1984
1985 dlm->dlm_thread_task = NULL;
1986 dlm->dlm_reco_thread_task = NULL;
1987 dlm->dlm_worker = NULL;
1988 init_waitqueue_head(&dlm->dlm_thread_wq);
1989 init_waitqueue_head(&dlm->dlm_reco_thread_wq);
1990 init_waitqueue_head(&dlm->reco.event);
1991 init_waitqueue_head(&dlm->ast_wq);
1992 init_waitqueue_head(&dlm->migration_wq);
1993 INIT_LIST_HEAD(&dlm->mle_hb_events);
1994
1995 dlm->joining_node = DLM_LOCK_RES_OWNER_UNKNOWN;
1996 init_waitqueue_head(&dlm->dlm_join_events);
1997
1998 dlm->reco.new_master = O2NM_INVALID_NODE_NUM;
1999 dlm->reco.dead_node = O2NM_INVALID_NODE_NUM;
2000
2001 atomic_set(&dlm->res_tot_count, 0);
2002 atomic_set(&dlm->res_cur_count, 0);
2003 for (i = 0; i < DLM_MLE_NUM_TYPES; ++i) {
2004 atomic_set(&dlm->mle_tot_count[i], 0);
2005 atomic_set(&dlm->mle_cur_count[i], 0);
2006 }
2007
2008 spin_lock_init(&dlm->work_lock);
2009 INIT_LIST_HEAD(&dlm->work_list);
2010 INIT_WORK(&dlm->dispatched_work, dlm_dispatch_work);
2011
2012 kref_init(&dlm->dlm_refs);
2013 dlm->dlm_state = DLM_CTXT_NEW;
2014
2015 INIT_LIST_HEAD(&dlm->dlm_eviction_callbacks);
2016
2017 mlog(0, "context init: refcount %u\n",
2018 atomic_read(&dlm->dlm_refs.refcount));
2019
2020 leave:
2021 return dlm;
2022 }
2023
2024 /*
2025 * Compare a requested locking protocol version against the current one.
2026 *
2027 * If the major numbers are different, they are incompatible.
2028 * If the current minor is greater than the request, they are incompatible.
2029 * If the current minor is less than or equal to the request, they are
2030 * compatible, and the requester should run at the current minor version.
2031 */
dlm_protocol_compare(struct dlm_protocol_version * existing,struct dlm_protocol_version * request)2032 static int dlm_protocol_compare(struct dlm_protocol_version *existing,
2033 struct dlm_protocol_version *request)
2034 {
2035 if (existing->pv_major != request->pv_major)
2036 return 1;
2037
2038 if (existing->pv_minor > request->pv_minor)
2039 return 1;
2040
2041 if (existing->pv_minor < request->pv_minor)
2042 request->pv_minor = existing->pv_minor;
2043
2044 return 0;
2045 }
2046
2047 /*
2048 * dlm_register_domain: one-time setup per "domain".
2049 *
2050 * The filesystem passes in the requested locking version via proto.
2051 * If registration was successful, proto will contain the negotiated
2052 * locking protocol.
2053 */
dlm_register_domain(const char * domain,u32 key,struct dlm_protocol_version * fs_proto)2054 struct dlm_ctxt * dlm_register_domain(const char *domain,
2055 u32 key,
2056 struct dlm_protocol_version *fs_proto)
2057 {
2058 int ret;
2059 struct dlm_ctxt *dlm = NULL;
2060 struct dlm_ctxt *new_ctxt = NULL;
2061
2062 if (strlen(domain) >= O2NM_MAX_NAME_LEN) {
2063 ret = -ENAMETOOLONG;
2064 mlog(ML_ERROR, "domain name length too long\n");
2065 goto leave;
2066 }
2067
2068 if (!o2hb_check_local_node_heartbeating()) {
2069 mlog(ML_ERROR, "the local node has not been configured, or is "
2070 "not heartbeating\n");
2071 ret = -EPROTO;
2072 goto leave;
2073 }
2074
2075 mlog(0, "register called for domain \"%s\"\n", domain);
2076
2077 retry:
2078 dlm = NULL;
2079 if (signal_pending(current)) {
2080 ret = -ERESTARTSYS;
2081 mlog_errno(ret);
2082 goto leave;
2083 }
2084
2085 spin_lock(&dlm_domain_lock);
2086
2087 dlm = __dlm_lookup_domain(domain);
2088 if (dlm) {
2089 if (dlm->dlm_state != DLM_CTXT_JOINED) {
2090 spin_unlock(&dlm_domain_lock);
2091
2092 mlog(0, "This ctxt is not joined yet!\n");
2093 wait_event_interruptible(dlm_domain_events,
2094 dlm_wait_on_domain_helper(
2095 domain));
2096 goto retry;
2097 }
2098
2099 if (dlm_protocol_compare(&dlm->fs_locking_proto, fs_proto)) {
2100 spin_unlock(&dlm_domain_lock);
2101 mlog(ML_ERROR,
2102 "Requested locking protocol version is not "
2103 "compatible with already registered domain "
2104 "\"%s\"\n", domain);
2105 ret = -EPROTO;
2106 goto leave;
2107 }
2108
2109 __dlm_get(dlm);
2110 dlm->num_joins++;
2111
2112 spin_unlock(&dlm_domain_lock);
2113
2114 ret = 0;
2115 goto leave;
2116 }
2117
2118 /* doesn't exist */
2119 if (!new_ctxt) {
2120 spin_unlock(&dlm_domain_lock);
2121
2122 new_ctxt = dlm_alloc_ctxt(domain, key);
2123 if (new_ctxt)
2124 goto retry;
2125
2126 ret = -ENOMEM;
2127 mlog_errno(ret);
2128 goto leave;
2129 }
2130
2131 /* a little variable switch-a-roo here... */
2132 dlm = new_ctxt;
2133 new_ctxt = NULL;
2134
2135 /* add the new domain */
2136 list_add_tail(&dlm->list, &dlm_domains);
2137 spin_unlock(&dlm_domain_lock);
2138
2139 /*
2140 * Pass the locking protocol version into the join. If the join
2141 * succeeds, it will have the negotiated protocol set.
2142 */
2143 dlm->dlm_locking_proto = dlm_protocol;
2144 dlm->fs_locking_proto = *fs_proto;
2145
2146 ret = dlm_join_domain(dlm);
2147 if (ret) {
2148 mlog_errno(ret);
2149 dlm_put(dlm);
2150 goto leave;
2151 }
2152
2153 /* Tell the caller what locking protocol we negotiated */
2154 *fs_proto = dlm->fs_locking_proto;
2155
2156 ret = 0;
2157 leave:
2158 if (new_ctxt)
2159 dlm_free_ctxt_mem(new_ctxt);
2160
2161 if (ret < 0)
2162 dlm = ERR_PTR(ret);
2163
2164 return dlm;
2165 }
2166 EXPORT_SYMBOL_GPL(dlm_register_domain);
2167
2168 static LIST_HEAD(dlm_join_handlers);
2169
dlm_unregister_net_handlers(void)2170 static void dlm_unregister_net_handlers(void)
2171 {
2172 o2net_unregister_handler_list(&dlm_join_handlers);
2173 }
2174
dlm_register_net_handlers(void)2175 static int dlm_register_net_handlers(void)
2176 {
2177 int status = 0;
2178
2179 status = o2net_register_handler(DLM_QUERY_JOIN_MSG, DLM_MOD_KEY,
2180 sizeof(struct dlm_query_join_request),
2181 dlm_query_join_handler,
2182 NULL, NULL, &dlm_join_handlers);
2183 if (status)
2184 goto bail;
2185
2186 status = o2net_register_handler(DLM_ASSERT_JOINED_MSG, DLM_MOD_KEY,
2187 sizeof(struct dlm_assert_joined),
2188 dlm_assert_joined_handler,
2189 NULL, NULL, &dlm_join_handlers);
2190 if (status)
2191 goto bail;
2192
2193 status = o2net_register_handler(DLM_CANCEL_JOIN_MSG, DLM_MOD_KEY,
2194 sizeof(struct dlm_cancel_join),
2195 dlm_cancel_join_handler,
2196 NULL, NULL, &dlm_join_handlers);
2197 if (status)
2198 goto bail;
2199
2200 status = o2net_register_handler(DLM_QUERY_REGION, DLM_MOD_KEY,
2201 sizeof(struct dlm_query_region),
2202 dlm_query_region_handler,
2203 NULL, NULL, &dlm_join_handlers);
2204
2205 if (status)
2206 goto bail;
2207
2208 status = o2net_register_handler(DLM_QUERY_NODEINFO, DLM_MOD_KEY,
2209 sizeof(struct dlm_query_nodeinfo),
2210 dlm_query_nodeinfo_handler,
2211 NULL, NULL, &dlm_join_handlers);
2212 bail:
2213 if (status < 0)
2214 dlm_unregister_net_handlers();
2215
2216 return status;
2217 }
2218
2219 /* Domain eviction callback handling.
2220 *
2221 * The file system requires notification of node death *before* the
2222 * dlm completes it's recovery work, otherwise it may be able to
2223 * acquire locks on resources requiring recovery. Since the dlm can
2224 * evict a node from it's domain *before* heartbeat fires, a similar
2225 * mechanism is required. */
2226
2227 /* Eviction is not expected to happen often, so a per-domain lock is
2228 * not necessary. Eviction callbacks are allowed to sleep for short
2229 * periods of time. */
2230 static DECLARE_RWSEM(dlm_callback_sem);
2231
dlm_fire_domain_eviction_callbacks(struct dlm_ctxt * dlm,int node_num)2232 void dlm_fire_domain_eviction_callbacks(struct dlm_ctxt *dlm,
2233 int node_num)
2234 {
2235 struct list_head *iter;
2236 struct dlm_eviction_cb *cb;
2237
2238 down_read(&dlm_callback_sem);
2239 list_for_each(iter, &dlm->dlm_eviction_callbacks) {
2240 cb = list_entry(iter, struct dlm_eviction_cb, ec_item);
2241
2242 cb->ec_func(node_num, cb->ec_data);
2243 }
2244 up_read(&dlm_callback_sem);
2245 }
2246
dlm_setup_eviction_cb(struct dlm_eviction_cb * cb,dlm_eviction_func * f,void * data)2247 void dlm_setup_eviction_cb(struct dlm_eviction_cb *cb,
2248 dlm_eviction_func *f,
2249 void *data)
2250 {
2251 INIT_LIST_HEAD(&cb->ec_item);
2252 cb->ec_func = f;
2253 cb->ec_data = data;
2254 }
2255 EXPORT_SYMBOL_GPL(dlm_setup_eviction_cb);
2256
dlm_register_eviction_cb(struct dlm_ctxt * dlm,struct dlm_eviction_cb * cb)2257 void dlm_register_eviction_cb(struct dlm_ctxt *dlm,
2258 struct dlm_eviction_cb *cb)
2259 {
2260 down_write(&dlm_callback_sem);
2261 list_add_tail(&cb->ec_item, &dlm->dlm_eviction_callbacks);
2262 up_write(&dlm_callback_sem);
2263 }
2264 EXPORT_SYMBOL_GPL(dlm_register_eviction_cb);
2265
dlm_unregister_eviction_cb(struct dlm_eviction_cb * cb)2266 void dlm_unregister_eviction_cb(struct dlm_eviction_cb *cb)
2267 {
2268 down_write(&dlm_callback_sem);
2269 list_del_init(&cb->ec_item);
2270 up_write(&dlm_callback_sem);
2271 }
2272 EXPORT_SYMBOL_GPL(dlm_unregister_eviction_cb);
2273
dlm_init(void)2274 static int __init dlm_init(void)
2275 {
2276 int status;
2277
2278 dlm_print_version();
2279
2280 status = dlm_init_mle_cache();
2281 if (status) {
2282 mlog(ML_ERROR, "Could not create o2dlm_mle slabcache\n");
2283 goto error;
2284 }
2285
2286 status = dlm_init_master_caches();
2287 if (status) {
2288 mlog(ML_ERROR, "Could not create o2dlm_lockres and "
2289 "o2dlm_lockname slabcaches\n");
2290 goto error;
2291 }
2292
2293 status = dlm_init_lock_cache();
2294 if (status) {
2295 mlog(ML_ERROR, "Count not create o2dlm_lock slabcache\n");
2296 goto error;
2297 }
2298
2299 status = dlm_register_net_handlers();
2300 if (status) {
2301 mlog(ML_ERROR, "Unable to register network handlers\n");
2302 goto error;
2303 }
2304
2305 status = dlm_create_debugfs_root();
2306 if (status)
2307 goto error;
2308
2309 return 0;
2310 error:
2311 dlm_unregister_net_handlers();
2312 dlm_destroy_lock_cache();
2313 dlm_destroy_master_caches();
2314 dlm_destroy_mle_cache();
2315 return -1;
2316 }
2317
dlm_exit(void)2318 static void __exit dlm_exit (void)
2319 {
2320 dlm_destroy_debugfs_root();
2321 dlm_unregister_net_handlers();
2322 dlm_destroy_lock_cache();
2323 dlm_destroy_master_caches();
2324 dlm_destroy_mle_cache();
2325 }
2326
2327 MODULE_AUTHOR("Oracle");
2328 MODULE_LICENSE("GPL");
2329
2330 module_init(dlm_init);
2331 module_exit(dlm_exit);
2332