1 /* -*- mode: c; c-basic-offset: 8; -*-
2 * vim: noexpandtab sw=8 ts=8 sts=0:
6 * defines domain join / leave apis
8 * Copyright (C) 2004 Oracle. All rights reserved.
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.
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.
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.
27 #include <linux/module.h>
28 #include <linux/types.h>
29 #include <linux/slab.h>
30 #include <linux/highmem.h>
31 #include <linux/utsname.h>
32 #include <linux/init.h>
33 #include <linux/spinlock.h>
34 #include <linux/delay.h>
35 #include <linux/err.h>
37 #include "cluster/heartbeat.h"
38 #include "cluster/nodemanager.h"
39 #include "cluster/tcp.h"
42 #include "dlmcommon.h"
44 #include "dlmdomain.h"
48 #define MLOG_MASK_PREFIX (ML_DLM|ML_DLM_DOMAIN)
49 #include "cluster/masklog.h"
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
57 static inline void byte_set_bit(u8 nr, u8 map[])
59 map[nr >> 3] |= (1UL << (nr & 7));
62 static inline int byte_test_bit(u8 nr, u8 map[])
64 return ((1UL << (nr & 7)) & (map[nr >> 3])) != 0;
67 static inline void byte_copymap(u8 dmap[], unsigned long smap[],
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);
81 static void dlm_free_pagevec(void **vec, int pages)
84 free_page((unsigned long)vec[pages]);
88 static void **dlm_alloc_pagevec(int pages)
90 void **vec = kmalloc(pages * sizeof(void *), GFP_KERNEL);
96 for (i = 0; i < pages; i++)
97 if (!(vec[i] = (void *)__get_free_page(GFP_KERNEL)))
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);
105 dlm_free_pagevec(vec, i);
111 * spinlock lock ordering: if multiple locks are needed, obey this ordering:
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
122 DEFINE_SPINLOCK(dlm_domain_lock);
123 LIST_HEAD(dlm_domains);
124 static DECLARE_WAIT_QUEUE_HEAD(dlm_domain_events);
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.
132 static const struct dlm_protocol_version dlm_protocol = {
137 #define DLM_DOMAIN_BACKOFF_MS 200
139 static int dlm_query_join_handler(struct o2net_msg *msg, u32 len, void *data,
141 static int dlm_assert_joined_handler(struct o2net_msg *msg, u32 len, void *data,
143 static int dlm_cancel_join_handler(struct o2net_msg *msg, u32 len, void *data,
145 static int dlm_exit_domain_handler(struct o2net_msg *msg, u32 len, void *data,
147 static int dlm_protocol_compare(struct dlm_protocol_version *existing,
148 struct dlm_protocol_version *request);
150 static void dlm_unregister_domain_handlers(struct dlm_ctxt *dlm);
152 void __dlm_unhash_lockres(struct dlm_lock_resource *lockres)
154 if (!hlist_unhashed(&lockres->hash_node)) {
155 hlist_del_init(&lockres->hash_node);
156 dlm_lockres_put(lockres);
160 void __dlm_insert_lockres(struct dlm_ctxt *dlm,
161 struct dlm_lock_resource *res)
163 struct hlist_head *bucket;
166 assert_spin_locked(&dlm->spinlock);
169 bucket = dlm_lockres_hash(dlm, q->hash);
171 /* get a reference for our hashtable */
172 dlm_lockres_get(res);
174 hlist_add_head(&res->hash_node, bucket);
177 struct dlm_lock_resource * __dlm_lookup_lockres_full(struct dlm_ctxt *dlm,
182 struct hlist_head *bucket;
183 struct hlist_node *list;
185 mlog_entry("%.*s\n", len, name);
187 assert_spin_locked(&dlm->spinlock);
189 bucket = dlm_lockres_hash(dlm, hash);
191 hlist_for_each(list, bucket) {
192 struct dlm_lock_resource *res = hlist_entry(list,
193 struct dlm_lock_resource, hash_node);
194 if (res->lockname.name[0] != name[0])
196 if (unlikely(res->lockname.len != len))
198 if (memcmp(res->lockname.name + 1, name + 1, len - 1))
200 dlm_lockres_get(res);
206 /* intended to be called by functions which do not care about lock
207 * resources which are being purged (most net _handler functions).
208 * this will return NULL for any lock resource which is found but
209 * currently in the process of dropping its mastery reference.
210 * use __dlm_lookup_lockres_full when you need the lock resource
211 * regardless (e.g. dlm_get_lock_resource) */
212 struct dlm_lock_resource * __dlm_lookup_lockres(struct dlm_ctxt *dlm,
217 struct dlm_lock_resource *res = NULL;
219 mlog_entry("%.*s\n", len, name);
221 assert_spin_locked(&dlm->spinlock);
223 res = __dlm_lookup_lockres_full(dlm, name, len, hash);
225 spin_lock(&res->spinlock);
226 if (res->state & DLM_LOCK_RES_DROPPING_REF) {
227 spin_unlock(&res->spinlock);
228 dlm_lockres_put(res);
231 spin_unlock(&res->spinlock);
237 struct dlm_lock_resource * dlm_lookup_lockres(struct dlm_ctxt *dlm,
241 struct dlm_lock_resource *res;
242 unsigned int hash = dlm_lockid_hash(name, len);
244 spin_lock(&dlm->spinlock);
245 res = __dlm_lookup_lockres(dlm, name, len, hash);
246 spin_unlock(&dlm->spinlock);
250 static struct dlm_ctxt * __dlm_lookup_domain_full(const char *domain, int len)
252 struct dlm_ctxt *tmp = NULL;
253 struct list_head *iter;
255 assert_spin_locked(&dlm_domain_lock);
257 /* tmp->name here is always NULL terminated,
258 * but domain may not be! */
259 list_for_each(iter, &dlm_domains) {
260 tmp = list_entry (iter, struct dlm_ctxt, list);
261 if (strlen(tmp->name) == len &&
262 memcmp(tmp->name, domain, len)==0)
270 /* For null terminated domain strings ONLY */
271 static struct dlm_ctxt * __dlm_lookup_domain(const char *domain)
273 assert_spin_locked(&dlm_domain_lock);
275 return __dlm_lookup_domain_full(domain, strlen(domain));
279 /* returns true on one of two conditions:
280 * 1) the domain does not exist
281 * 2) the domain exists and it's state is "joined" */
282 static int dlm_wait_on_domain_helper(const char *domain)
285 struct dlm_ctxt *tmp = NULL;
287 spin_lock(&dlm_domain_lock);
289 tmp = __dlm_lookup_domain(domain);
292 else if (tmp->dlm_state == DLM_CTXT_JOINED)
295 spin_unlock(&dlm_domain_lock);
299 static void dlm_free_ctxt_mem(struct dlm_ctxt *dlm)
301 if (dlm->lockres_hash)
302 dlm_free_pagevec((void **)dlm->lockres_hash, DLM_HASH_PAGES);
310 /* A little strange - this function will be called while holding
311 * dlm_domain_lock and is expected to be holding it on the way out. We
312 * will however drop and reacquire it multiple times */
313 static void dlm_ctxt_release(struct kref *kref)
315 struct dlm_ctxt *dlm;
317 dlm = container_of(kref, struct dlm_ctxt, dlm_refs);
319 BUG_ON(dlm->num_joins);
320 BUG_ON(dlm->dlm_state == DLM_CTXT_JOINED);
322 /* we may still be in the list if we hit an error during join. */
323 list_del_init(&dlm->list);
325 spin_unlock(&dlm_domain_lock);
327 mlog(0, "freeing memory from domain %s\n", dlm->name);
329 wake_up(&dlm_domain_events);
331 dlm_free_ctxt_mem(dlm);
333 spin_lock(&dlm_domain_lock);
336 void dlm_put(struct dlm_ctxt *dlm)
338 spin_lock(&dlm_domain_lock);
339 kref_put(&dlm->dlm_refs, dlm_ctxt_release);
340 spin_unlock(&dlm_domain_lock);
343 static void __dlm_get(struct dlm_ctxt *dlm)
345 kref_get(&dlm->dlm_refs);
348 /* given a questionable reference to a dlm object, gets a reference if
349 * it can find it in the list, otherwise returns NULL in which case
350 * you shouldn't trust your pointer. */
351 struct dlm_ctxt *dlm_grab(struct dlm_ctxt *dlm)
353 struct list_head *iter;
354 struct dlm_ctxt *target = NULL;
356 spin_lock(&dlm_domain_lock);
358 list_for_each(iter, &dlm_domains) {
359 target = list_entry (iter, struct dlm_ctxt, list);
369 spin_unlock(&dlm_domain_lock);
374 int dlm_domain_fully_joined(struct dlm_ctxt *dlm)
378 spin_lock(&dlm_domain_lock);
379 ret = (dlm->dlm_state == DLM_CTXT_JOINED) ||
380 (dlm->dlm_state == DLM_CTXT_IN_SHUTDOWN);
381 spin_unlock(&dlm_domain_lock);
386 static void dlm_destroy_dlm_worker(struct dlm_ctxt *dlm)
388 if (dlm->dlm_worker) {
389 flush_workqueue(dlm->dlm_worker);
390 destroy_workqueue(dlm->dlm_worker);
391 dlm->dlm_worker = NULL;
395 static void dlm_complete_dlm_shutdown(struct dlm_ctxt *dlm)
397 dlm_unregister_domain_handlers(dlm);
398 dlm_complete_thread(dlm);
399 dlm_complete_recovery_thread(dlm);
400 dlm_destroy_dlm_worker(dlm);
402 /* We've left the domain. Now we can take ourselves out of the
403 * list and allow the kref stuff to help us free the
405 spin_lock(&dlm_domain_lock);
406 list_del_init(&dlm->list);
407 spin_unlock(&dlm_domain_lock);
409 /* Wake up anyone waiting for us to remove this domain */
410 wake_up(&dlm_domain_events);
413 static int dlm_migrate_all_locks(struct dlm_ctxt *dlm)
415 int i, num, n, ret = 0;
416 struct dlm_lock_resource *res;
417 struct hlist_node *iter;
418 struct hlist_head *bucket;
421 mlog(0, "Migrating locks from domain %s\n", dlm->name);
424 spin_lock(&dlm->spinlock);
425 for (i = 0; i < DLM_HASH_BUCKETS; i++) {
428 bucket = dlm_lockres_hash(dlm, i);
429 iter = bucket->first;
432 res = hlist_entry(iter, struct dlm_lock_resource,
434 dlm_lockres_get(res);
435 /* migrate, if necessary. this will drop the dlm
436 * spinlock and retake it if it does migration. */
437 dropped = dlm_empty_lockres(dlm, res);
439 spin_lock(&res->spinlock);
440 __dlm_lockres_calc_usage(dlm, res);
441 iter = res->hash_node.next;
442 spin_unlock(&res->spinlock);
444 dlm_lockres_put(res);
449 cond_resched_lock(&dlm->spinlock);
451 mlog(0, "%s: touched %d lockreses in bucket %d "
452 "(tot=%d)\n", dlm->name, n, i, num);
454 spin_unlock(&dlm->spinlock);
455 wake_up(&dlm->dlm_thread_wq);
457 /* let the dlm thread take care of purging, keep scanning until
458 * nothing remains in the hash */
460 mlog(0, "%s: %d lock resources in hash last pass\n",
464 mlog(0, "DONE Migrating locks from domain %s\n", dlm->name);
468 static int dlm_no_joining_node(struct dlm_ctxt *dlm)
472 spin_lock(&dlm->spinlock);
473 ret = dlm->joining_node == DLM_LOCK_RES_OWNER_UNKNOWN;
474 spin_unlock(&dlm->spinlock);
479 static void dlm_mark_domain_leaving(struct dlm_ctxt *dlm)
481 /* Yikes, a double spinlock! I need domain_lock for the dlm
482 * state and the dlm spinlock for join state... Sorry! */
484 spin_lock(&dlm_domain_lock);
485 spin_lock(&dlm->spinlock);
487 if (dlm->joining_node != DLM_LOCK_RES_OWNER_UNKNOWN) {
488 mlog(0, "Node %d is joining, we wait on it.\n",
490 spin_unlock(&dlm->spinlock);
491 spin_unlock(&dlm_domain_lock);
493 wait_event(dlm->dlm_join_events, dlm_no_joining_node(dlm));
497 dlm->dlm_state = DLM_CTXT_LEAVING;
498 spin_unlock(&dlm->spinlock);
499 spin_unlock(&dlm_domain_lock);
502 static void __dlm_print_nodes(struct dlm_ctxt *dlm)
506 assert_spin_locked(&dlm->spinlock);
508 printk(KERN_INFO "ocfs2_dlm: Nodes in domain (\"%s\"): ", dlm->name);
510 while ((node = find_next_bit(dlm->domain_map, O2NM_MAX_NODES,
511 node + 1)) < O2NM_MAX_NODES) {
517 static int dlm_exit_domain_handler(struct o2net_msg *msg, u32 len, void *data,
520 struct dlm_ctxt *dlm = data;
522 struct dlm_exit_domain *exit_msg = (struct dlm_exit_domain *) msg->buf;
524 mlog_entry("%p %u %p", msg, len, data);
529 node = exit_msg->node_idx;
531 printk(KERN_INFO "ocfs2_dlm: Node %u leaves domain %s\n", node, dlm->name);
533 spin_lock(&dlm->spinlock);
534 clear_bit(node, dlm->domain_map);
535 __dlm_print_nodes(dlm);
537 /* notify anything attached to the heartbeat events */
538 dlm_hb_event_notify_attached(dlm, node, 0);
540 spin_unlock(&dlm->spinlock);
547 static int dlm_send_one_domain_exit(struct dlm_ctxt *dlm,
551 struct dlm_exit_domain leave_msg;
553 mlog(0, "Asking node %u if we can leave the domain %s me = %u\n",
554 node, dlm->name, dlm->node_num);
556 memset(&leave_msg, 0, sizeof(leave_msg));
557 leave_msg.node_idx = dlm->node_num;
559 status = o2net_send_message(DLM_EXIT_DOMAIN_MSG, dlm->key,
560 &leave_msg, sizeof(leave_msg), node,
563 mlog(0, "status return %d from o2net_send_message\n", status);
569 static void dlm_leave_domain(struct dlm_ctxt *dlm)
571 int node, clear_node, status;
573 /* At this point we've migrated away all our locks and won't
574 * accept mastership of new ones. The dlm is responsible for
575 * almost nothing now. We make sure not to confuse any joining
576 * nodes and then commence shutdown procedure. */
578 spin_lock(&dlm->spinlock);
579 /* Clear ourselves from the domain map */
580 clear_bit(dlm->node_num, dlm->domain_map);
581 while ((node = find_next_bit(dlm->domain_map, O2NM_MAX_NODES,
582 0)) < O2NM_MAX_NODES) {
583 /* Drop the dlm spinlock. This is safe wrt the domain_map.
584 * -nodes cannot be added now as the
585 * query_join_handlers knows to respond with OK_NO_MAP
586 * -we catch the right network errors if a node is
587 * removed from the map while we're sending him the
589 spin_unlock(&dlm->spinlock);
593 status = dlm_send_one_domain_exit(dlm, node);
595 status != -ENOPROTOOPT &&
596 status != -ENOTCONN) {
597 mlog(ML_NOTICE, "Error %d sending domain exit message "
598 "to node %d\n", status, node);
600 /* Not sure what to do here but lets sleep for
601 * a bit in case this was a transient
603 msleep(DLM_DOMAIN_BACKOFF_MS);
607 spin_lock(&dlm->spinlock);
608 /* If we're not clearing the node bit then we intend
609 * to loop back around to try again. */
611 clear_bit(node, dlm->domain_map);
613 spin_unlock(&dlm->spinlock);
616 int dlm_joined(struct dlm_ctxt *dlm)
620 spin_lock(&dlm_domain_lock);
622 if (dlm->dlm_state == DLM_CTXT_JOINED)
625 spin_unlock(&dlm_domain_lock);
630 int dlm_shutting_down(struct dlm_ctxt *dlm)
634 spin_lock(&dlm_domain_lock);
636 if (dlm->dlm_state == DLM_CTXT_IN_SHUTDOWN)
639 spin_unlock(&dlm_domain_lock);
644 void dlm_unregister_domain(struct dlm_ctxt *dlm)
647 struct dlm_lock_resource *res;
649 spin_lock(&dlm_domain_lock);
650 BUG_ON(dlm->dlm_state != DLM_CTXT_JOINED);
651 BUG_ON(!dlm->num_joins);
654 if (!dlm->num_joins) {
655 /* We mark it "in shutdown" now so new register
656 * requests wait until we've completely left the
657 * domain. Don't use DLM_CTXT_LEAVING yet as we still
658 * want new domain joins to communicate with us at
659 * least until we've completed migration of our
661 dlm->dlm_state = DLM_CTXT_IN_SHUTDOWN;
664 spin_unlock(&dlm_domain_lock);
667 mlog(0, "shutting down domain %s\n", dlm->name);
669 /* We changed dlm state, notify the thread */
670 dlm_kick_thread(dlm, NULL);
672 while (dlm_migrate_all_locks(dlm)) {
673 /* Give dlm_thread time to purge the lockres' */
675 mlog(0, "%s: more migration to do\n", dlm->name);
678 /* This list should be empty. If not, print remaining lockres */
679 if (!list_empty(&dlm->tracking_list)) {
680 mlog(ML_ERROR, "Following lockres' are still on the "
682 list_for_each_entry(res, &dlm->tracking_list, tracking)
683 dlm_print_one_lock_resource(res);
686 dlm_mark_domain_leaving(dlm);
687 dlm_leave_domain(dlm);
688 dlm_complete_dlm_shutdown(dlm);
692 EXPORT_SYMBOL_GPL(dlm_unregister_domain);
694 static int dlm_query_join_proto_check(char *proto_type, int node,
695 struct dlm_protocol_version *ours,
696 struct dlm_protocol_version *request)
699 struct dlm_protocol_version proto = *request;
701 if (!dlm_protocol_compare(ours, &proto)) {
703 "node %u wanted to join with %s locking protocol "
704 "%u.%u, we respond with %u.%u\n",
708 proto.pv_major, proto.pv_minor);
709 request->pv_minor = proto.pv_minor;
713 "Node %u wanted to join with %s locking "
714 "protocol %u.%u, but we have %u.%u, disallowing\n",
727 * struct dlm_query_join_packet is made up of four one-byte fields. They
728 * are effectively in big-endian order already. However, little-endian
729 * machines swap them before putting the packet on the wire (because
730 * query_join's response is a status, and that status is treated as a u32
731 * on the wire). Thus, a big-endian and little-endian machines will treat
732 * this structure differently.
734 * The solution is to have little-endian machines swap the structure when
735 * converting from the structure to the u32 representation. This will
736 * result in the structure having the correct format on the wire no matter
737 * the host endian format.
739 static void dlm_query_join_packet_to_wire(struct dlm_query_join_packet *packet,
742 union dlm_query_join_response response;
744 response.packet = *packet;
745 *wire = cpu_to_be32(response.intval);
748 static void dlm_query_join_wire_to_packet(u32 wire,
749 struct dlm_query_join_packet *packet)
751 union dlm_query_join_response response;
753 response.intval = cpu_to_be32(wire);
754 *packet = response.packet;
757 static int dlm_query_join_handler(struct o2net_msg *msg, u32 len, void *data,
760 struct dlm_query_join_request *query;
761 struct dlm_query_join_packet packet = {
762 .code = JOIN_DISALLOW,
764 struct dlm_ctxt *dlm = NULL;
768 query = (struct dlm_query_join_request *) msg->buf;
770 mlog(0, "node %u wants to join domain %s\n", query->node_idx,
774 * If heartbeat doesn't consider the node live, tell it
775 * to back off and try again. This gives heartbeat a chance
778 if (!o2hb_check_node_heartbeating(query->node_idx)) {
779 mlog(0, "node %u is not in our live map yet\n",
782 packet.code = JOIN_DISALLOW;
786 packet.code = JOIN_OK_NO_MAP;
788 spin_lock(&dlm_domain_lock);
789 dlm = __dlm_lookup_domain_full(query->domain, query->name_len);
794 * There is a small window where the joining node may not see the
795 * node(s) that just left but still part of the cluster. DISALLOW
796 * join request if joining node has different node map.
799 while (nodenum < O2NM_MAX_NODES) {
800 if (test_bit(nodenum, dlm->domain_map)) {
801 if (!byte_test_bit(nodenum, query->node_map)) {
802 mlog(0, "disallow join as node %u does not "
803 "have node %u in its nodemap\n",
804 query->node_idx, nodenum);
805 packet.code = JOIN_DISALLOW;
812 /* Once the dlm ctxt is marked as leaving then we don't want
813 * to be put in someone's domain map.
814 * Also, explicitly disallow joining at certain troublesome
815 * times (ie. during recovery). */
816 if (dlm && dlm->dlm_state != DLM_CTXT_LEAVING) {
817 int bit = query->node_idx;
818 spin_lock(&dlm->spinlock);
820 if (dlm->dlm_state == DLM_CTXT_NEW &&
821 dlm->joining_node == DLM_LOCK_RES_OWNER_UNKNOWN) {
822 /*If this is a brand new context and we
823 * haven't started our join process yet, then
824 * the other node won the race. */
825 packet.code = JOIN_OK_NO_MAP;
826 } else if (dlm->joining_node != DLM_LOCK_RES_OWNER_UNKNOWN) {
827 /* Disallow parallel joins. */
828 packet.code = JOIN_DISALLOW;
829 } else if (dlm->reco.state & DLM_RECO_STATE_ACTIVE) {
830 mlog(0, "node %u trying to join, but recovery "
831 "is ongoing.\n", bit);
832 packet.code = JOIN_DISALLOW;
833 } else if (test_bit(bit, dlm->recovery_map)) {
834 mlog(0, "node %u trying to join, but it "
835 "still needs recovery.\n", bit);
836 packet.code = JOIN_DISALLOW;
837 } else if (test_bit(bit, dlm->domain_map)) {
838 mlog(0, "node %u trying to join, but it "
839 "is still in the domain! needs recovery?\n",
841 packet.code = JOIN_DISALLOW;
843 /* Alright we're fully a part of this domain
844 * so we keep some state as to who's joining
845 * and indicate to him that needs to be fixed
848 /* Make sure we speak compatible locking protocols. */
849 if (dlm_query_join_proto_check("DLM", bit,
850 &dlm->dlm_locking_proto,
851 &query->dlm_proto)) {
852 packet.code = JOIN_PROTOCOL_MISMATCH;
853 } else if (dlm_query_join_proto_check("fs", bit,
854 &dlm->fs_locking_proto,
856 packet.code = JOIN_PROTOCOL_MISMATCH;
858 packet.dlm_minor = query->dlm_proto.pv_minor;
859 packet.fs_minor = query->fs_proto.pv_minor;
860 packet.code = JOIN_OK;
861 __dlm_set_joining_node(dlm, query->node_idx);
865 spin_unlock(&dlm->spinlock);
868 spin_unlock(&dlm_domain_lock);
871 mlog(0, "We respond with %u\n", packet.code);
873 dlm_query_join_packet_to_wire(&packet, &response);
877 static int dlm_assert_joined_handler(struct o2net_msg *msg, u32 len, void *data,
880 struct dlm_assert_joined *assert;
881 struct dlm_ctxt *dlm = NULL;
883 assert = (struct dlm_assert_joined *) msg->buf;
885 mlog(0, "node %u asserts join on domain %s\n", assert->node_idx,
888 spin_lock(&dlm_domain_lock);
889 dlm = __dlm_lookup_domain_full(assert->domain, assert->name_len);
890 /* XXX should we consider no dlm ctxt an error? */
892 spin_lock(&dlm->spinlock);
894 /* Alright, this node has officially joined our
895 * domain. Set him in the map and clean up our
896 * leftover join state. */
897 BUG_ON(dlm->joining_node != assert->node_idx);
898 set_bit(assert->node_idx, dlm->domain_map);
899 __dlm_set_joining_node(dlm, DLM_LOCK_RES_OWNER_UNKNOWN);
901 printk(KERN_INFO "ocfs2_dlm: Node %u joins domain %s\n",
902 assert->node_idx, dlm->name);
903 __dlm_print_nodes(dlm);
905 /* notify anything attached to the heartbeat events */
906 dlm_hb_event_notify_attached(dlm, assert->node_idx, 1);
908 spin_unlock(&dlm->spinlock);
910 spin_unlock(&dlm_domain_lock);
915 static int dlm_cancel_join_handler(struct o2net_msg *msg, u32 len, void *data,
918 struct dlm_cancel_join *cancel;
919 struct dlm_ctxt *dlm = NULL;
921 cancel = (struct dlm_cancel_join *) msg->buf;
923 mlog(0, "node %u cancels join on domain %s\n", cancel->node_idx,
926 spin_lock(&dlm_domain_lock);
927 dlm = __dlm_lookup_domain_full(cancel->domain, cancel->name_len);
930 spin_lock(&dlm->spinlock);
932 /* Yikes, this guy wants to cancel his join. No
933 * problem, we simply cleanup our join state. */
934 BUG_ON(dlm->joining_node != cancel->node_idx);
935 __dlm_set_joining_node(dlm, DLM_LOCK_RES_OWNER_UNKNOWN);
937 spin_unlock(&dlm->spinlock);
939 spin_unlock(&dlm_domain_lock);
944 static int dlm_send_one_join_cancel(struct dlm_ctxt *dlm,
948 struct dlm_cancel_join cancel_msg;
950 memset(&cancel_msg, 0, sizeof(cancel_msg));
951 cancel_msg.node_idx = dlm->node_num;
952 cancel_msg.name_len = strlen(dlm->name);
953 memcpy(cancel_msg.domain, dlm->name, cancel_msg.name_len);
955 status = o2net_send_message(DLM_CANCEL_JOIN_MSG, DLM_MOD_KEY,
956 &cancel_msg, sizeof(cancel_msg), node,
967 /* map_size should be in bytes. */
968 static int dlm_send_join_cancels(struct dlm_ctxt *dlm,
969 unsigned long *node_map,
970 unsigned int map_size)
975 if (map_size != (BITS_TO_LONGS(O2NM_MAX_NODES) *
976 sizeof(unsigned long))) {
978 "map_size %u != BITS_TO_LONGS(O2NM_MAX_NODES) %u\n",
979 map_size, (unsigned)BITS_TO_LONGS(O2NM_MAX_NODES));
985 while ((node = find_next_bit(node_map, O2NM_MAX_NODES,
986 node + 1)) < O2NM_MAX_NODES) {
987 if (node == dlm->node_num)
990 tmpstat = dlm_send_one_join_cancel(dlm, node);
992 mlog(ML_ERROR, "Error return %d cancelling join on "
993 "node %d\n", tmpstat, node);
1004 static int dlm_request_join(struct dlm_ctxt *dlm,
1006 enum dlm_query_join_response_code *response)
1009 struct dlm_query_join_request join_msg;
1010 struct dlm_query_join_packet packet;
1013 mlog(0, "querying node %d\n", node);
1015 memset(&join_msg, 0, sizeof(join_msg));
1016 join_msg.node_idx = dlm->node_num;
1017 join_msg.name_len = strlen(dlm->name);
1018 memcpy(join_msg.domain, dlm->name, join_msg.name_len);
1019 join_msg.dlm_proto = dlm->dlm_locking_proto;
1020 join_msg.fs_proto = dlm->fs_locking_proto;
1022 /* copy live node map to join message */
1023 byte_copymap(join_msg.node_map, dlm->live_nodes_map, O2NM_MAX_NODES);
1025 status = o2net_send_message(DLM_QUERY_JOIN_MSG, DLM_MOD_KEY, &join_msg,
1026 sizeof(join_msg), node,
1028 if (status < 0 && status != -ENOPROTOOPT) {
1032 dlm_query_join_wire_to_packet(join_resp, &packet);
1034 /* -ENOPROTOOPT from the net code means the other side isn't
1035 listening for our message type -- that's fine, it means
1036 his dlm isn't up, so we can consider him a 'yes' but not
1037 joined into the domain. */
1038 if (status == -ENOPROTOOPT) {
1040 *response = JOIN_OK_NO_MAP;
1041 } else if (packet.code == JOIN_DISALLOW ||
1042 packet.code == JOIN_OK_NO_MAP) {
1043 *response = packet.code;
1044 } else if (packet.code == JOIN_PROTOCOL_MISMATCH) {
1046 "This node requested DLM locking protocol %u.%u and "
1047 "filesystem locking protocol %u.%u. At least one of "
1048 "the protocol versions on node %d is not compatible, "
1050 dlm->dlm_locking_proto.pv_major,
1051 dlm->dlm_locking_proto.pv_minor,
1052 dlm->fs_locking_proto.pv_major,
1053 dlm->fs_locking_proto.pv_minor,
1056 *response = packet.code;
1057 } else if (packet.code == JOIN_OK) {
1058 *response = packet.code;
1059 /* Use the same locking protocol as the remote node */
1060 dlm->dlm_locking_proto.pv_minor = packet.dlm_minor;
1061 dlm->fs_locking_proto.pv_minor = packet.fs_minor;
1063 "Node %d responds JOIN_OK with DLM locking protocol "
1064 "%u.%u and fs locking protocol %u.%u\n",
1066 dlm->dlm_locking_proto.pv_major,
1067 dlm->dlm_locking_proto.pv_minor,
1068 dlm->fs_locking_proto.pv_major,
1069 dlm->fs_locking_proto.pv_minor);
1072 mlog(ML_ERROR, "invalid response %d from node %u\n",
1076 mlog(0, "status %d, node %d response is %d\n", status, node,
1083 static int dlm_send_one_join_assert(struct dlm_ctxt *dlm,
1087 struct dlm_assert_joined assert_msg;
1089 mlog(0, "Sending join assert to node %u\n", node);
1091 memset(&assert_msg, 0, sizeof(assert_msg));
1092 assert_msg.node_idx = dlm->node_num;
1093 assert_msg.name_len = strlen(dlm->name);
1094 memcpy(assert_msg.domain, dlm->name, assert_msg.name_len);
1096 status = o2net_send_message(DLM_ASSERT_JOINED_MSG, DLM_MOD_KEY,
1097 &assert_msg, sizeof(assert_msg), node,
1105 static void dlm_send_join_asserts(struct dlm_ctxt *dlm,
1106 unsigned long *node_map)
1108 int status, node, live;
1112 while ((node = find_next_bit(node_map, O2NM_MAX_NODES,
1113 node + 1)) < O2NM_MAX_NODES) {
1114 if (node == dlm->node_num)
1118 /* It is very important that this message be
1119 * received so we spin until either the node
1120 * has died or it gets the message. */
1121 status = dlm_send_one_join_assert(dlm, node);
1123 spin_lock(&dlm->spinlock);
1124 live = test_bit(node, dlm->live_nodes_map);
1125 spin_unlock(&dlm->spinlock);
1128 mlog(ML_ERROR, "Error return %d asserting "
1129 "join on node %d\n", status, node);
1131 /* give us some time between errors... */
1133 msleep(DLM_DOMAIN_BACKOFF_MS);
1135 } while (status && live);
1139 struct domain_join_ctxt {
1140 unsigned long live_map[BITS_TO_LONGS(O2NM_MAX_NODES)];
1141 unsigned long yes_resp_map[BITS_TO_LONGS(O2NM_MAX_NODES)];
1144 static int dlm_should_restart_join(struct dlm_ctxt *dlm,
1145 struct domain_join_ctxt *ctxt,
1146 enum dlm_query_join_response_code response)
1150 if (response == JOIN_DISALLOW) {
1151 mlog(0, "Latest response of disallow -- should restart\n");
1155 spin_lock(&dlm->spinlock);
1156 /* For now, we restart the process if the node maps have
1158 ret = memcmp(ctxt->live_map, dlm->live_nodes_map,
1159 sizeof(dlm->live_nodes_map));
1160 spin_unlock(&dlm->spinlock);
1163 mlog(0, "Node maps changed -- should restart\n");
1168 static int dlm_try_to_join_domain(struct dlm_ctxt *dlm)
1170 int status = 0, tmpstat, node;
1171 struct domain_join_ctxt *ctxt;
1172 enum dlm_query_join_response_code response = JOIN_DISALLOW;
1174 mlog_entry("%p", dlm);
1176 ctxt = kzalloc(sizeof(*ctxt), GFP_KERNEL);
1183 /* group sem locking should work for us here -- we're already
1184 * registered for heartbeat events so filling this should be
1185 * atomic wrt getting those handlers called. */
1186 o2hb_fill_node_map(dlm->live_nodes_map, sizeof(dlm->live_nodes_map));
1188 spin_lock(&dlm->spinlock);
1189 memcpy(ctxt->live_map, dlm->live_nodes_map, sizeof(ctxt->live_map));
1191 __dlm_set_joining_node(dlm, dlm->node_num);
1193 spin_unlock(&dlm->spinlock);
1196 while ((node = find_next_bit(ctxt->live_map, O2NM_MAX_NODES,
1197 node + 1)) < O2NM_MAX_NODES) {
1198 if (node == dlm->node_num)
1201 status = dlm_request_join(dlm, node, &response);
1207 /* Ok, either we got a response or the node doesn't have a
1209 if (response == JOIN_OK)
1210 set_bit(node, ctxt->yes_resp_map);
1212 if (dlm_should_restart_join(dlm, ctxt, response)) {
1218 mlog(0, "Yay, done querying nodes!\n");
1220 /* Yay, everyone agree's we can join the domain. My domain is
1221 * comprised of all nodes who were put in the
1222 * yes_resp_map. Copy that into our domain map and send a join
1223 * assert message to clean up everyone elses state. */
1224 spin_lock(&dlm->spinlock);
1225 memcpy(dlm->domain_map, ctxt->yes_resp_map,
1226 sizeof(ctxt->yes_resp_map));
1227 set_bit(dlm->node_num, dlm->domain_map);
1228 spin_unlock(&dlm->spinlock);
1230 dlm_send_join_asserts(dlm, ctxt->yes_resp_map);
1232 /* Joined state *must* be set before the joining node
1233 * information, otherwise the query_join handler may read no
1234 * current joiner but a state of NEW and tell joining nodes
1235 * we're not in the domain. */
1236 spin_lock(&dlm_domain_lock);
1237 dlm->dlm_state = DLM_CTXT_JOINED;
1239 spin_unlock(&dlm_domain_lock);
1242 spin_lock(&dlm->spinlock);
1243 __dlm_set_joining_node(dlm, DLM_LOCK_RES_OWNER_UNKNOWN);
1245 __dlm_print_nodes(dlm);
1246 spin_unlock(&dlm->spinlock);
1249 /* Do we need to send a cancel message to any nodes? */
1251 tmpstat = dlm_send_join_cancels(dlm,
1253 sizeof(ctxt->yes_resp_map));
1255 mlog_errno(tmpstat);
1260 mlog(0, "returning %d\n", status);
1264 static void dlm_unregister_domain_handlers(struct dlm_ctxt *dlm)
1266 o2hb_unregister_callback(NULL, &dlm->dlm_hb_up);
1267 o2hb_unregister_callback(NULL, &dlm->dlm_hb_down);
1268 o2net_unregister_handler_list(&dlm->dlm_domain_handlers);
1271 static int dlm_register_domain_handlers(struct dlm_ctxt *dlm)
1275 mlog(0, "registering handlers.\n");
1277 o2hb_setup_callback(&dlm->dlm_hb_down, O2HB_NODE_DOWN_CB,
1278 dlm_hb_node_down_cb, dlm, DLM_HB_NODE_DOWN_PRI);
1279 status = o2hb_register_callback(NULL, &dlm->dlm_hb_down);
1283 o2hb_setup_callback(&dlm->dlm_hb_up, O2HB_NODE_UP_CB,
1284 dlm_hb_node_up_cb, dlm, DLM_HB_NODE_UP_PRI);
1285 status = o2hb_register_callback(NULL, &dlm->dlm_hb_up);
1289 status = o2net_register_handler(DLM_MASTER_REQUEST_MSG, dlm->key,
1290 sizeof(struct dlm_master_request),
1291 dlm_master_request_handler,
1292 dlm, NULL, &dlm->dlm_domain_handlers);
1296 status = o2net_register_handler(DLM_ASSERT_MASTER_MSG, dlm->key,
1297 sizeof(struct dlm_assert_master),
1298 dlm_assert_master_handler,
1299 dlm, dlm_assert_master_post_handler,
1300 &dlm->dlm_domain_handlers);
1304 status = o2net_register_handler(DLM_CREATE_LOCK_MSG, dlm->key,
1305 sizeof(struct dlm_create_lock),
1306 dlm_create_lock_handler,
1307 dlm, NULL, &dlm->dlm_domain_handlers);
1311 status = o2net_register_handler(DLM_CONVERT_LOCK_MSG, dlm->key,
1312 DLM_CONVERT_LOCK_MAX_LEN,
1313 dlm_convert_lock_handler,
1314 dlm, NULL, &dlm->dlm_domain_handlers);
1318 status = o2net_register_handler(DLM_UNLOCK_LOCK_MSG, dlm->key,
1319 DLM_UNLOCK_LOCK_MAX_LEN,
1320 dlm_unlock_lock_handler,
1321 dlm, NULL, &dlm->dlm_domain_handlers);
1325 status = o2net_register_handler(DLM_PROXY_AST_MSG, dlm->key,
1326 DLM_PROXY_AST_MAX_LEN,
1327 dlm_proxy_ast_handler,
1328 dlm, NULL, &dlm->dlm_domain_handlers);
1332 status = o2net_register_handler(DLM_EXIT_DOMAIN_MSG, dlm->key,
1333 sizeof(struct dlm_exit_domain),
1334 dlm_exit_domain_handler,
1335 dlm, NULL, &dlm->dlm_domain_handlers);
1339 status = o2net_register_handler(DLM_DEREF_LOCKRES_MSG, dlm->key,
1340 sizeof(struct dlm_deref_lockres),
1341 dlm_deref_lockres_handler,
1342 dlm, NULL, &dlm->dlm_domain_handlers);
1346 status = o2net_register_handler(DLM_MIGRATE_REQUEST_MSG, dlm->key,
1347 sizeof(struct dlm_migrate_request),
1348 dlm_migrate_request_handler,
1349 dlm, NULL, &dlm->dlm_domain_handlers);
1353 status = o2net_register_handler(DLM_MIG_LOCKRES_MSG, dlm->key,
1354 DLM_MIG_LOCKRES_MAX_LEN,
1355 dlm_mig_lockres_handler,
1356 dlm, NULL, &dlm->dlm_domain_handlers);
1360 status = o2net_register_handler(DLM_MASTER_REQUERY_MSG, dlm->key,
1361 sizeof(struct dlm_master_requery),
1362 dlm_master_requery_handler,
1363 dlm, NULL, &dlm->dlm_domain_handlers);
1367 status = o2net_register_handler(DLM_LOCK_REQUEST_MSG, dlm->key,
1368 sizeof(struct dlm_lock_request),
1369 dlm_request_all_locks_handler,
1370 dlm, NULL, &dlm->dlm_domain_handlers);
1374 status = o2net_register_handler(DLM_RECO_DATA_DONE_MSG, dlm->key,
1375 sizeof(struct dlm_reco_data_done),
1376 dlm_reco_data_done_handler,
1377 dlm, NULL, &dlm->dlm_domain_handlers);
1381 status = o2net_register_handler(DLM_BEGIN_RECO_MSG, dlm->key,
1382 sizeof(struct dlm_begin_reco),
1383 dlm_begin_reco_handler,
1384 dlm, NULL, &dlm->dlm_domain_handlers);
1388 status = o2net_register_handler(DLM_FINALIZE_RECO_MSG, dlm->key,
1389 sizeof(struct dlm_finalize_reco),
1390 dlm_finalize_reco_handler,
1391 dlm, NULL, &dlm->dlm_domain_handlers);
1397 dlm_unregister_domain_handlers(dlm);
1402 static int dlm_join_domain(struct dlm_ctxt *dlm)
1405 unsigned int backoff;
1406 unsigned int total_backoff = 0;
1410 mlog(0, "Join domain %s\n", dlm->name);
1412 status = dlm_register_domain_handlers(dlm);
1418 status = dlm_launch_thread(dlm);
1424 status = dlm_launch_recovery_thread(dlm);
1430 dlm->dlm_worker = create_singlethread_workqueue("dlm_wq");
1431 if (!dlm->dlm_worker) {
1438 status = dlm_try_to_join_domain(dlm);
1440 /* If we're racing another node to the join, then we
1441 * need to back off temporarily and let them
1443 #define DLM_JOIN_TIMEOUT_MSECS 90000
1444 if (status == -EAGAIN) {
1445 if (signal_pending(current)) {
1446 status = -ERESTARTSYS;
1451 msecs_to_jiffies(DLM_JOIN_TIMEOUT_MSECS)) {
1452 status = -ERESTARTSYS;
1453 mlog(ML_NOTICE, "Timed out joining dlm domain "
1454 "%s after %u msecs\n", dlm->name,
1455 jiffies_to_msecs(total_backoff));
1461 * <dale> No, after you!
1463 * <dale> But you first!
1466 backoff = (unsigned int)(jiffies & 0x3);
1467 backoff *= DLM_DOMAIN_BACKOFF_MS;
1468 total_backoff += backoff;
1469 mlog(0, "backoff %d\n", backoff);
1472 } while (status == -EAGAIN);
1481 wake_up(&dlm_domain_events);
1484 dlm_unregister_domain_handlers(dlm);
1485 dlm_complete_thread(dlm);
1486 dlm_complete_recovery_thread(dlm);
1487 dlm_destroy_dlm_worker(dlm);
1493 static struct dlm_ctxt *dlm_alloc_ctxt(const char *domain,
1497 struct dlm_ctxt *dlm = NULL;
1499 dlm = kzalloc(sizeof(*dlm), GFP_KERNEL);
1501 mlog_errno(-ENOMEM);
1505 dlm->name = kmalloc(strlen(domain) + 1, GFP_KERNEL);
1506 if (dlm->name == NULL) {
1507 mlog_errno(-ENOMEM);
1513 dlm->lockres_hash = (struct hlist_head **)dlm_alloc_pagevec(DLM_HASH_PAGES);
1514 if (!dlm->lockres_hash) {
1515 mlog_errno(-ENOMEM);
1522 for (i = 0; i < DLM_HASH_BUCKETS; i++)
1523 INIT_HLIST_HEAD(dlm_lockres_hash(dlm, i));
1525 strcpy(dlm->name, domain);
1527 dlm->node_num = o2nm_this_node();
1529 spin_lock_init(&dlm->spinlock);
1530 spin_lock_init(&dlm->master_lock);
1531 spin_lock_init(&dlm->ast_lock);
1532 INIT_LIST_HEAD(&dlm->list);
1533 INIT_LIST_HEAD(&dlm->dirty_list);
1534 INIT_LIST_HEAD(&dlm->reco.resources);
1535 INIT_LIST_HEAD(&dlm->reco.received);
1536 INIT_LIST_HEAD(&dlm->reco.node_data);
1537 INIT_LIST_HEAD(&dlm->purge_list);
1538 INIT_LIST_HEAD(&dlm->dlm_domain_handlers);
1539 INIT_LIST_HEAD(&dlm->tracking_list);
1540 dlm->reco.state = 0;
1542 INIT_LIST_HEAD(&dlm->pending_asts);
1543 INIT_LIST_HEAD(&dlm->pending_basts);
1545 mlog(0, "dlm->recovery_map=%p, &(dlm->recovery_map[0])=%p\n",
1546 dlm->recovery_map, &(dlm->recovery_map[0]));
1548 memset(dlm->recovery_map, 0, sizeof(dlm->recovery_map));
1549 memset(dlm->live_nodes_map, 0, sizeof(dlm->live_nodes_map));
1550 memset(dlm->domain_map, 0, sizeof(dlm->domain_map));
1552 dlm->dlm_thread_task = NULL;
1553 dlm->dlm_reco_thread_task = NULL;
1554 dlm->dlm_worker = NULL;
1555 init_waitqueue_head(&dlm->dlm_thread_wq);
1556 init_waitqueue_head(&dlm->dlm_reco_thread_wq);
1557 init_waitqueue_head(&dlm->reco.event);
1558 init_waitqueue_head(&dlm->ast_wq);
1559 init_waitqueue_head(&dlm->migration_wq);
1560 INIT_LIST_HEAD(&dlm->master_list);
1561 INIT_LIST_HEAD(&dlm->mle_hb_events);
1563 dlm->joining_node = DLM_LOCK_RES_OWNER_UNKNOWN;
1564 init_waitqueue_head(&dlm->dlm_join_events);
1566 dlm->reco.new_master = O2NM_INVALID_NODE_NUM;
1567 dlm->reco.dead_node = O2NM_INVALID_NODE_NUM;
1568 atomic_set(&dlm->local_resources, 0);
1569 atomic_set(&dlm->remote_resources, 0);
1570 atomic_set(&dlm->unknown_resources, 0);
1572 spin_lock_init(&dlm->work_lock);
1573 INIT_LIST_HEAD(&dlm->work_list);
1574 INIT_WORK(&dlm->dispatched_work, dlm_dispatch_work);
1576 kref_init(&dlm->dlm_refs);
1577 dlm->dlm_state = DLM_CTXT_NEW;
1579 INIT_LIST_HEAD(&dlm->dlm_eviction_callbacks);
1581 mlog(0, "context init: refcount %u\n",
1582 atomic_read(&dlm->dlm_refs.refcount));
1589 * Compare a requested locking protocol version against the current one.
1591 * If the major numbers are different, they are incompatible.
1592 * If the current minor is greater than the request, they are incompatible.
1593 * If the current minor is less than or equal to the request, they are
1594 * compatible, and the requester should run at the current minor version.
1596 static int dlm_protocol_compare(struct dlm_protocol_version *existing,
1597 struct dlm_protocol_version *request)
1599 if (existing->pv_major != request->pv_major)
1602 if (existing->pv_minor > request->pv_minor)
1605 if (existing->pv_minor < request->pv_minor)
1606 request->pv_minor = existing->pv_minor;
1612 * dlm_register_domain: one-time setup per "domain".
1614 * The filesystem passes in the requested locking version via proto.
1615 * If registration was successful, proto will contain the negotiated
1618 struct dlm_ctxt * dlm_register_domain(const char *domain,
1620 struct dlm_protocol_version *fs_proto)
1623 struct dlm_ctxt *dlm = NULL;
1624 struct dlm_ctxt *new_ctxt = NULL;
1626 if (strlen(domain) > O2NM_MAX_NAME_LEN) {
1627 ret = -ENAMETOOLONG;
1628 mlog(ML_ERROR, "domain name length too long\n");
1632 if (!o2hb_check_local_node_heartbeating()) {
1633 mlog(ML_ERROR, "the local node has not been configured, or is "
1634 "not heartbeating\n");
1639 mlog(0, "register called for domain \"%s\"\n", domain);
1643 if (signal_pending(current)) {
1649 spin_lock(&dlm_domain_lock);
1651 dlm = __dlm_lookup_domain(domain);
1653 if (dlm->dlm_state != DLM_CTXT_JOINED) {
1654 spin_unlock(&dlm_domain_lock);
1656 mlog(0, "This ctxt is not joined yet!\n");
1657 wait_event_interruptible(dlm_domain_events,
1658 dlm_wait_on_domain_helper(
1663 if (dlm_protocol_compare(&dlm->fs_locking_proto, fs_proto)) {
1665 "Requested locking protocol version is not "
1666 "compatible with already registered domain "
1667 "\"%s\"\n", domain);
1675 spin_unlock(&dlm_domain_lock);
1683 spin_unlock(&dlm_domain_lock);
1685 new_ctxt = dlm_alloc_ctxt(domain, key);
1694 /* a little variable switch-a-roo here... */
1698 /* add the new domain */
1699 list_add_tail(&dlm->list, &dlm_domains);
1700 spin_unlock(&dlm_domain_lock);
1703 * Pass the locking protocol version into the join. If the join
1704 * succeeds, it will have the negotiated protocol set.
1706 dlm->dlm_locking_proto = dlm_protocol;
1707 dlm->fs_locking_proto = *fs_proto;
1709 ret = dlm_join_domain(dlm);
1716 /* Tell the caller what locking protocol we negotiated */
1717 *fs_proto = dlm->fs_locking_proto;
1722 dlm_free_ctxt_mem(new_ctxt);
1729 EXPORT_SYMBOL_GPL(dlm_register_domain);
1731 static LIST_HEAD(dlm_join_handlers);
1733 static void dlm_unregister_net_handlers(void)
1735 o2net_unregister_handler_list(&dlm_join_handlers);
1738 static int dlm_register_net_handlers(void)
1742 status = o2net_register_handler(DLM_QUERY_JOIN_MSG, DLM_MOD_KEY,
1743 sizeof(struct dlm_query_join_request),
1744 dlm_query_join_handler,
1745 NULL, NULL, &dlm_join_handlers);
1749 status = o2net_register_handler(DLM_ASSERT_JOINED_MSG, DLM_MOD_KEY,
1750 sizeof(struct dlm_assert_joined),
1751 dlm_assert_joined_handler,
1752 NULL, NULL, &dlm_join_handlers);
1756 status = o2net_register_handler(DLM_CANCEL_JOIN_MSG, DLM_MOD_KEY,
1757 sizeof(struct dlm_cancel_join),
1758 dlm_cancel_join_handler,
1759 NULL, NULL, &dlm_join_handlers);
1763 dlm_unregister_net_handlers();
1768 /* Domain eviction callback handling.
1770 * The file system requires notification of node death *before* the
1771 * dlm completes it's recovery work, otherwise it may be able to
1772 * acquire locks on resources requiring recovery. Since the dlm can
1773 * evict a node from it's domain *before* heartbeat fires, a similar
1774 * mechanism is required. */
1776 /* Eviction is not expected to happen often, so a per-domain lock is
1777 * not necessary. Eviction callbacks are allowed to sleep for short
1778 * periods of time. */
1779 static DECLARE_RWSEM(dlm_callback_sem);
1781 void dlm_fire_domain_eviction_callbacks(struct dlm_ctxt *dlm,
1784 struct list_head *iter;
1785 struct dlm_eviction_cb *cb;
1787 down_read(&dlm_callback_sem);
1788 list_for_each(iter, &dlm->dlm_eviction_callbacks) {
1789 cb = list_entry(iter, struct dlm_eviction_cb, ec_item);
1791 cb->ec_func(node_num, cb->ec_data);
1793 up_read(&dlm_callback_sem);
1796 void dlm_setup_eviction_cb(struct dlm_eviction_cb *cb,
1797 dlm_eviction_func *f,
1800 INIT_LIST_HEAD(&cb->ec_item);
1804 EXPORT_SYMBOL_GPL(dlm_setup_eviction_cb);
1806 void dlm_register_eviction_cb(struct dlm_ctxt *dlm,
1807 struct dlm_eviction_cb *cb)
1809 down_write(&dlm_callback_sem);
1810 list_add_tail(&cb->ec_item, &dlm->dlm_eviction_callbacks);
1811 up_write(&dlm_callback_sem);
1813 EXPORT_SYMBOL_GPL(dlm_register_eviction_cb);
1815 void dlm_unregister_eviction_cb(struct dlm_eviction_cb *cb)
1817 down_write(&dlm_callback_sem);
1818 list_del_init(&cb->ec_item);
1819 up_write(&dlm_callback_sem);
1821 EXPORT_SYMBOL_GPL(dlm_unregister_eviction_cb);
1823 static int __init dlm_init(void)
1827 dlm_print_version();
1829 status = dlm_init_mle_cache();
1831 mlog(ML_ERROR, "Could not create o2dlm_mle slabcache\n");
1835 status = dlm_init_master_caches();
1837 mlog(ML_ERROR, "Could not create o2dlm_lockres and "
1838 "o2dlm_lockname slabcaches\n");
1842 status = dlm_init_lock_cache();
1844 mlog(ML_ERROR, "Count not create o2dlm_lock slabcache\n");
1848 status = dlm_register_net_handlers();
1850 mlog(ML_ERROR, "Unable to register network handlers\n");
1856 dlm_destroy_lock_cache();
1857 dlm_destroy_master_caches();
1858 dlm_destroy_mle_cache();
1862 static void __exit dlm_exit (void)
1864 dlm_unregister_net_handlers();
1865 dlm_destroy_lock_cache();
1866 dlm_destroy_master_caches();
1867 dlm_destroy_mle_cache();
1870 MODULE_AUTHOR("Oracle");
1871 MODULE_LICENSE("GPL");
1873 module_init(dlm_init);
1874 module_exit(dlm_exit);