xref: /openbmc/linux/fs/ocfs2/dlm/dlmrecovery.c (revision ee89bd6b)
1 /* -*- mode: c; c-basic-offset: 8; -*-
2  * vim: noexpandtab sw=8 ts=8 sts=0:
3  *
4  * dlmrecovery.c
5  *
6  * recovery stuff
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 
28 #include <linux/module.h>
29 #include <linux/fs.h>
30 #include <linux/types.h>
31 #include <linux/slab.h>
32 #include <linux/highmem.h>
33 #include <linux/init.h>
34 #include <linux/sysctl.h>
35 #include <linux/random.h>
36 #include <linux/blkdev.h>
37 #include <linux/socket.h>
38 #include <linux/inet.h>
39 #include <linux/timer.h>
40 #include <linux/kthread.h>
41 #include <linux/delay.h>
42 
43 
44 #include "cluster/heartbeat.h"
45 #include "cluster/nodemanager.h"
46 #include "cluster/tcp.h"
47 
48 #include "dlmapi.h"
49 #include "dlmcommon.h"
50 #include "dlmdomain.h"
51 
52 #define MLOG_MASK_PREFIX (ML_DLM|ML_DLM_RECOVERY)
53 #include "cluster/masklog.h"
54 
55 static void dlm_do_local_recovery_cleanup(struct dlm_ctxt *dlm, u8 dead_node);
56 
57 static int dlm_recovery_thread(void *data);
58 void dlm_complete_recovery_thread(struct dlm_ctxt *dlm);
59 int dlm_launch_recovery_thread(struct dlm_ctxt *dlm);
60 void dlm_kick_recovery_thread(struct dlm_ctxt *dlm);
61 static int dlm_do_recovery(struct dlm_ctxt *dlm);
62 
63 static int dlm_pick_recovery_master(struct dlm_ctxt *dlm);
64 static int dlm_remaster_locks(struct dlm_ctxt *dlm, u8 dead_node);
65 static int dlm_init_recovery_area(struct dlm_ctxt *dlm, u8 dead_node);
66 static int dlm_request_all_locks(struct dlm_ctxt *dlm,
67 				 u8 request_from, u8 dead_node);
68 static void dlm_destroy_recovery_area(struct dlm_ctxt *dlm, u8 dead_node);
69 
70 static inline int dlm_num_locks_in_lockres(struct dlm_lock_resource *res);
71 static void dlm_init_migratable_lockres(struct dlm_migratable_lockres *mres,
72 					const char *lockname, int namelen,
73 					int total_locks, u64 cookie,
74 					u8 flags, u8 master);
75 static int dlm_send_mig_lockres_msg(struct dlm_ctxt *dlm,
76 				    struct dlm_migratable_lockres *mres,
77 				    u8 send_to,
78 				    struct dlm_lock_resource *res,
79 				    int total_locks);
80 static int dlm_process_recovery_data(struct dlm_ctxt *dlm,
81 				     struct dlm_lock_resource *res,
82 				     struct dlm_migratable_lockres *mres);
83 static int dlm_send_finalize_reco_message(struct dlm_ctxt *dlm);
84 static int dlm_send_all_done_msg(struct dlm_ctxt *dlm,
85 				 u8 dead_node, u8 send_to);
86 static int dlm_send_begin_reco_message(struct dlm_ctxt *dlm, u8 dead_node);
87 static void dlm_move_reco_locks_to_list(struct dlm_ctxt *dlm,
88 					struct list_head *list, u8 dead_node);
89 static void dlm_finish_local_lockres_recovery(struct dlm_ctxt *dlm,
90 					      u8 dead_node, u8 new_master);
91 static void dlm_reco_ast(void *astdata);
92 static void dlm_reco_bast(void *astdata, int blocked_type);
93 static void dlm_reco_unlock_ast(void *astdata, enum dlm_status st);
94 static void dlm_request_all_locks_worker(struct dlm_work_item *item,
95 					 void *data);
96 static void dlm_mig_lockres_worker(struct dlm_work_item *item, void *data);
97 static int dlm_lockres_master_requery(struct dlm_ctxt *dlm,
98 				      struct dlm_lock_resource *res,
99 				      u8 *real_master);
100 
101 static u64 dlm_get_next_mig_cookie(void);
102 
103 static DEFINE_SPINLOCK(dlm_reco_state_lock);
104 static DEFINE_SPINLOCK(dlm_mig_cookie_lock);
105 static u64 dlm_mig_cookie = 1;
106 
107 static u64 dlm_get_next_mig_cookie(void)
108 {
109 	u64 c;
110 	spin_lock(&dlm_mig_cookie_lock);
111 	c = dlm_mig_cookie;
112 	if (dlm_mig_cookie == (~0ULL))
113 		dlm_mig_cookie = 1;
114 	else
115 		dlm_mig_cookie++;
116 	spin_unlock(&dlm_mig_cookie_lock);
117 	return c;
118 }
119 
120 static inline void dlm_set_reco_dead_node(struct dlm_ctxt *dlm,
121 					  u8 dead_node)
122 {
123 	assert_spin_locked(&dlm->spinlock);
124 	if (dlm->reco.dead_node != dead_node)
125 		mlog(0, "%s: changing dead_node from %u to %u\n",
126 		     dlm->name, dlm->reco.dead_node, dead_node);
127 	dlm->reco.dead_node = dead_node;
128 }
129 
130 static inline void dlm_set_reco_master(struct dlm_ctxt *dlm,
131 				       u8 master)
132 {
133 	assert_spin_locked(&dlm->spinlock);
134 	mlog(0, "%s: changing new_master from %u to %u\n",
135 	     dlm->name, dlm->reco.new_master, master);
136 	dlm->reco.new_master = master;
137 }
138 
139 static inline void __dlm_reset_recovery(struct dlm_ctxt *dlm)
140 {
141 	assert_spin_locked(&dlm->spinlock);
142 	clear_bit(dlm->reco.dead_node, dlm->recovery_map);
143 	dlm_set_reco_dead_node(dlm, O2NM_INVALID_NODE_NUM);
144 	dlm_set_reco_master(dlm, O2NM_INVALID_NODE_NUM);
145 }
146 
147 static inline void dlm_reset_recovery(struct dlm_ctxt *dlm)
148 {
149 	spin_lock(&dlm->spinlock);
150 	__dlm_reset_recovery(dlm);
151 	spin_unlock(&dlm->spinlock);
152 }
153 
154 /* Worker function used during recovery. */
155 void dlm_dispatch_work(struct work_struct *work)
156 {
157 	struct dlm_ctxt *dlm =
158 		container_of(work, struct dlm_ctxt, dispatched_work);
159 	LIST_HEAD(tmp_list);
160 	struct dlm_work_item *item, *next;
161 	dlm_workfunc_t *workfunc;
162 	int tot=0;
163 
164 	spin_lock(&dlm->work_lock);
165 	list_splice_init(&dlm->work_list, &tmp_list);
166 	spin_unlock(&dlm->work_lock);
167 
168 	list_for_each_entry(item, &tmp_list, list) {
169 		tot++;
170 	}
171 	mlog(0, "%s: work thread has %d work items\n", dlm->name, tot);
172 
173 	list_for_each_entry_safe(item, next, &tmp_list, list) {
174 		workfunc = item->func;
175 		list_del_init(&item->list);
176 
177 		/* already have ref on dlm to avoid having
178 		 * it disappear.  just double-check. */
179 		BUG_ON(item->dlm != dlm);
180 
181 		/* this is allowed to sleep and
182 		 * call network stuff */
183 		workfunc(item, item->data);
184 
185 		dlm_put(dlm);
186 		kfree(item);
187 	}
188 }
189 
190 /*
191  * RECOVERY THREAD
192  */
193 
194 void dlm_kick_recovery_thread(struct dlm_ctxt *dlm)
195 {
196 	/* wake the recovery thread
197 	 * this will wake the reco thread in one of three places
198 	 * 1) sleeping with no recovery happening
199 	 * 2) sleeping with recovery mastered elsewhere
200 	 * 3) recovery mastered here, waiting on reco data */
201 
202 	wake_up(&dlm->dlm_reco_thread_wq);
203 }
204 
205 /* Launch the recovery thread */
206 int dlm_launch_recovery_thread(struct dlm_ctxt *dlm)
207 {
208 	mlog(0, "starting dlm recovery thread...\n");
209 
210 	dlm->dlm_reco_thread_task = kthread_run(dlm_recovery_thread, dlm,
211 						"dlm_reco_thread");
212 	if (IS_ERR(dlm->dlm_reco_thread_task)) {
213 		mlog_errno(PTR_ERR(dlm->dlm_reco_thread_task));
214 		dlm->dlm_reco_thread_task = NULL;
215 		return -EINVAL;
216 	}
217 
218 	return 0;
219 }
220 
221 void dlm_complete_recovery_thread(struct dlm_ctxt *dlm)
222 {
223 	if (dlm->dlm_reco_thread_task) {
224 		mlog(0, "waiting for dlm recovery thread to exit\n");
225 		kthread_stop(dlm->dlm_reco_thread_task);
226 		dlm->dlm_reco_thread_task = NULL;
227 	}
228 }
229 
230 
231 
232 /*
233  * this is lame, but here's how recovery works...
234  * 1) all recovery threads cluster wide will work on recovering
235  *    ONE node at a time
236  * 2) negotiate who will take over all the locks for the dead node.
237  *    thats right... ALL the locks.
238  * 3) once a new master is chosen, everyone scans all locks
239  *    and moves aside those mastered by the dead guy
240  * 4) each of these locks should be locked until recovery is done
241  * 5) the new master collects up all of secondary lock queue info
242  *    one lock at a time, forcing each node to communicate back
243  *    before continuing
244  * 6) each secondary lock queue responds with the full known lock info
245  * 7) once the new master has run all its locks, it sends a ALLDONE!
246  *    message to everyone
247  * 8) upon receiving this message, the secondary queue node unlocks
248  *    and responds to the ALLDONE
249  * 9) once the new master gets responses from everyone, he unlocks
250  *    everything and recovery for this dead node is done
251  *10) go back to 2) while there are still dead nodes
252  *
253  */
254 
255 static void dlm_print_reco_node_status(struct dlm_ctxt *dlm)
256 {
257 	struct dlm_reco_node_data *ndata;
258 	struct dlm_lock_resource *res;
259 
260 	mlog(ML_NOTICE, "%s(%d): recovery info, state=%s, dead=%u, master=%u\n",
261 	     dlm->name, task_pid_nr(dlm->dlm_reco_thread_task),
262 	     dlm->reco.state & DLM_RECO_STATE_ACTIVE ? "ACTIVE" : "inactive",
263 	     dlm->reco.dead_node, dlm->reco.new_master);
264 
265 	list_for_each_entry(ndata, &dlm->reco.node_data, list) {
266 		char *st = "unknown";
267 		switch (ndata->state) {
268 			case DLM_RECO_NODE_DATA_INIT:
269 				st = "init";
270 				break;
271 			case DLM_RECO_NODE_DATA_REQUESTING:
272 				st = "requesting";
273 				break;
274 			case DLM_RECO_NODE_DATA_DEAD:
275 				st = "dead";
276 				break;
277 			case DLM_RECO_NODE_DATA_RECEIVING:
278 				st = "receiving";
279 				break;
280 			case DLM_RECO_NODE_DATA_REQUESTED:
281 				st = "requested";
282 				break;
283 			case DLM_RECO_NODE_DATA_DONE:
284 				st = "done";
285 				break;
286 			case DLM_RECO_NODE_DATA_FINALIZE_SENT:
287 				st = "finalize-sent";
288 				break;
289 			default:
290 				st = "bad";
291 				break;
292 		}
293 		mlog(ML_NOTICE, "%s: reco state, node %u, state=%s\n",
294 		     dlm->name, ndata->node_num, st);
295 	}
296 	list_for_each_entry(res, &dlm->reco.resources, recovering) {
297 		mlog(ML_NOTICE, "%s: lockres %.*s on recovering list\n",
298 		     dlm->name, res->lockname.len, res->lockname.name);
299 	}
300 }
301 
302 #define DLM_RECO_THREAD_TIMEOUT_MS (5 * 1000)
303 
304 static int dlm_recovery_thread(void *data)
305 {
306 	int status;
307 	struct dlm_ctxt *dlm = data;
308 	unsigned long timeout = msecs_to_jiffies(DLM_RECO_THREAD_TIMEOUT_MS);
309 
310 	mlog(0, "dlm thread running for %s...\n", dlm->name);
311 
312 	while (!kthread_should_stop()) {
313 		if (dlm_domain_fully_joined(dlm)) {
314 			status = dlm_do_recovery(dlm);
315 			if (status == -EAGAIN) {
316 				/* do not sleep, recheck immediately. */
317 				continue;
318 			}
319 			if (status < 0)
320 				mlog_errno(status);
321 		}
322 
323 		wait_event_interruptible_timeout(dlm->dlm_reco_thread_wq,
324 						 kthread_should_stop(),
325 						 timeout);
326 	}
327 
328 	mlog(0, "quitting DLM recovery thread\n");
329 	return 0;
330 }
331 
332 /* returns true when the recovery master has contacted us */
333 static int dlm_reco_master_ready(struct dlm_ctxt *dlm)
334 {
335 	int ready;
336 	spin_lock(&dlm->spinlock);
337 	ready = (dlm->reco.new_master != O2NM_INVALID_NODE_NUM);
338 	spin_unlock(&dlm->spinlock);
339 	return ready;
340 }
341 
342 /* returns true if node is no longer in the domain
343  * could be dead or just not joined */
344 int dlm_is_node_dead(struct dlm_ctxt *dlm, u8 node)
345 {
346 	int dead;
347 	spin_lock(&dlm->spinlock);
348 	dead = !test_bit(node, dlm->domain_map);
349 	spin_unlock(&dlm->spinlock);
350 	return dead;
351 }
352 
353 /* returns true if node is no longer in the domain
354  * could be dead or just not joined */
355 static int dlm_is_node_recovered(struct dlm_ctxt *dlm, u8 node)
356 {
357 	int recovered;
358 	spin_lock(&dlm->spinlock);
359 	recovered = !test_bit(node, dlm->recovery_map);
360 	spin_unlock(&dlm->spinlock);
361 	return recovered;
362 }
363 
364 
365 void dlm_wait_for_node_death(struct dlm_ctxt *dlm, u8 node, int timeout)
366 {
367 	if (dlm_is_node_dead(dlm, node))
368 		return;
369 
370 	printk(KERN_NOTICE "o2dlm: Waiting on the death of node %u in "
371 	       "domain %s\n", node, dlm->name);
372 
373 	if (timeout)
374 		wait_event_timeout(dlm->dlm_reco_thread_wq,
375 				   dlm_is_node_dead(dlm, node),
376 				   msecs_to_jiffies(timeout));
377 	else
378 		wait_event(dlm->dlm_reco_thread_wq,
379 			   dlm_is_node_dead(dlm, node));
380 }
381 
382 void dlm_wait_for_node_recovery(struct dlm_ctxt *dlm, u8 node, int timeout)
383 {
384 	if (dlm_is_node_recovered(dlm, node))
385 		return;
386 
387 	printk(KERN_NOTICE "o2dlm: Waiting on the recovery of node %u in "
388 	       "domain %s\n", node, dlm->name);
389 
390 	if (timeout)
391 		wait_event_timeout(dlm->dlm_reco_thread_wq,
392 				   dlm_is_node_recovered(dlm, node),
393 				   msecs_to_jiffies(timeout));
394 	else
395 		wait_event(dlm->dlm_reco_thread_wq,
396 			   dlm_is_node_recovered(dlm, node));
397 }
398 
399 /* callers of the top-level api calls (dlmlock/dlmunlock) should
400  * block on the dlm->reco.event when recovery is in progress.
401  * the dlm recovery thread will set this state when it begins
402  * recovering a dead node (as the new master or not) and clear
403  * the state and wake as soon as all affected lock resources have
404  * been marked with the RECOVERY flag */
405 static int dlm_in_recovery(struct dlm_ctxt *dlm)
406 {
407 	int in_recovery;
408 	spin_lock(&dlm->spinlock);
409 	in_recovery = !!(dlm->reco.state & DLM_RECO_STATE_ACTIVE);
410 	spin_unlock(&dlm->spinlock);
411 	return in_recovery;
412 }
413 
414 
415 void dlm_wait_for_recovery(struct dlm_ctxt *dlm)
416 {
417 	if (dlm_in_recovery(dlm)) {
418 		mlog(0, "%s: reco thread %d in recovery: "
419 		     "state=%d, master=%u, dead=%u\n",
420 		     dlm->name, task_pid_nr(dlm->dlm_reco_thread_task),
421 		     dlm->reco.state, dlm->reco.new_master,
422 		     dlm->reco.dead_node);
423 	}
424 	wait_event(dlm->reco.event, !dlm_in_recovery(dlm));
425 }
426 
427 static void dlm_begin_recovery(struct dlm_ctxt *dlm)
428 {
429 	spin_lock(&dlm->spinlock);
430 	BUG_ON(dlm->reco.state & DLM_RECO_STATE_ACTIVE);
431 	printk(KERN_NOTICE "o2dlm: Begin recovery on domain %s for node %u\n",
432 	       dlm->name, dlm->reco.dead_node);
433 	dlm->reco.state |= DLM_RECO_STATE_ACTIVE;
434 	spin_unlock(&dlm->spinlock);
435 }
436 
437 static void dlm_end_recovery(struct dlm_ctxt *dlm)
438 {
439 	spin_lock(&dlm->spinlock);
440 	BUG_ON(!(dlm->reco.state & DLM_RECO_STATE_ACTIVE));
441 	dlm->reco.state &= ~DLM_RECO_STATE_ACTIVE;
442 	spin_unlock(&dlm->spinlock);
443 	printk(KERN_NOTICE "o2dlm: End recovery on domain %s\n", dlm->name);
444 	wake_up(&dlm->reco.event);
445 }
446 
447 static void dlm_print_recovery_master(struct dlm_ctxt *dlm)
448 {
449 	printk(KERN_NOTICE "o2dlm: Node %u (%s) is the Recovery Master for the "
450 	       "dead node %u in domain %s\n", dlm->reco.new_master,
451 	       (dlm->node_num == dlm->reco.new_master ? "me" : "he"),
452 	       dlm->reco.dead_node, dlm->name);
453 }
454 
455 static int dlm_do_recovery(struct dlm_ctxt *dlm)
456 {
457 	int status = 0;
458 	int ret;
459 
460 	spin_lock(&dlm->spinlock);
461 
462 	/* check to see if the new master has died */
463 	if (dlm->reco.new_master != O2NM_INVALID_NODE_NUM &&
464 	    test_bit(dlm->reco.new_master, dlm->recovery_map)) {
465 		mlog(0, "new master %u died while recovering %u!\n",
466 		     dlm->reco.new_master, dlm->reco.dead_node);
467 		/* unset the new_master, leave dead_node */
468 		dlm_set_reco_master(dlm, O2NM_INVALID_NODE_NUM);
469 	}
470 
471 	/* select a target to recover */
472 	if (dlm->reco.dead_node == O2NM_INVALID_NODE_NUM) {
473 		int bit;
474 
475 		bit = find_next_bit (dlm->recovery_map, O2NM_MAX_NODES, 0);
476 		if (bit >= O2NM_MAX_NODES || bit < 0)
477 			dlm_set_reco_dead_node(dlm, O2NM_INVALID_NODE_NUM);
478 		else
479 			dlm_set_reco_dead_node(dlm, bit);
480 	} else if (!test_bit(dlm->reco.dead_node, dlm->recovery_map)) {
481 		/* BUG? */
482 		mlog(ML_ERROR, "dead_node %u no longer in recovery map!\n",
483 		     dlm->reco.dead_node);
484 		dlm_set_reco_dead_node(dlm, O2NM_INVALID_NODE_NUM);
485 	}
486 
487 	if (dlm->reco.dead_node == O2NM_INVALID_NODE_NUM) {
488 		// mlog(0, "nothing to recover!  sleeping now!\n");
489 		spin_unlock(&dlm->spinlock);
490 		/* return to main thread loop and sleep. */
491 		return 0;
492 	}
493 	mlog(0, "%s(%d):recovery thread found node %u in the recovery map!\n",
494 	     dlm->name, task_pid_nr(dlm->dlm_reco_thread_task),
495 	     dlm->reco.dead_node);
496 	spin_unlock(&dlm->spinlock);
497 
498 	/* take write barrier */
499 	/* (stops the list reshuffling thread, proxy ast handling) */
500 	dlm_begin_recovery(dlm);
501 
502 	if (dlm->reco.new_master == dlm->node_num)
503 		goto master_here;
504 
505 	if (dlm->reco.new_master == O2NM_INVALID_NODE_NUM) {
506 		/* choose a new master, returns 0 if this node
507 		 * is the master, -EEXIST if it's another node.
508 		 * this does not return until a new master is chosen
509 		 * or recovery completes entirely. */
510 		ret = dlm_pick_recovery_master(dlm);
511 		if (!ret) {
512 			/* already notified everyone.  go. */
513 			goto master_here;
514 		}
515 		mlog(0, "another node will master this recovery session.\n");
516 	}
517 
518 	dlm_print_recovery_master(dlm);
519 
520 	/* it is safe to start everything back up here
521 	 * because all of the dead node's lock resources
522 	 * have been marked as in-recovery */
523 	dlm_end_recovery(dlm);
524 
525 	/* sleep out in main dlm_recovery_thread loop. */
526 	return 0;
527 
528 master_here:
529 	dlm_print_recovery_master(dlm);
530 
531 	status = dlm_remaster_locks(dlm, dlm->reco.dead_node);
532 	if (status < 0) {
533 		/* we should never hit this anymore */
534 		mlog(ML_ERROR, "%s: Error %d remastering locks for node %u, "
535 		     "retrying.\n", dlm->name, status, dlm->reco.dead_node);
536 		/* yield a bit to allow any final network messages
537 		 * to get handled on remaining nodes */
538 		msleep(100);
539 	} else {
540 		/* success!  see if any other nodes need recovery */
541 		mlog(0, "DONE mastering recovery of %s:%u here(this=%u)!\n",
542 		     dlm->name, dlm->reco.dead_node, dlm->node_num);
543 		dlm_reset_recovery(dlm);
544 	}
545 	dlm_end_recovery(dlm);
546 
547 	/* continue and look for another dead node */
548 	return -EAGAIN;
549 }
550 
551 static int dlm_remaster_locks(struct dlm_ctxt *dlm, u8 dead_node)
552 {
553 	int status = 0;
554 	struct dlm_reco_node_data *ndata;
555 	int all_nodes_done;
556 	int destroy = 0;
557 	int pass = 0;
558 
559 	do {
560 		/* we have become recovery master.  there is no escaping
561 		 * this, so just keep trying until we get it. */
562 		status = dlm_init_recovery_area(dlm, dead_node);
563 		if (status < 0) {
564 			mlog(ML_ERROR, "%s: failed to alloc recovery area, "
565 			     "retrying\n", dlm->name);
566 			msleep(1000);
567 		}
568 	} while (status != 0);
569 
570 	/* safe to access the node data list without a lock, since this
571 	 * process is the only one to change the list */
572 	list_for_each_entry(ndata, &dlm->reco.node_data, list) {
573 		BUG_ON(ndata->state != DLM_RECO_NODE_DATA_INIT);
574 		ndata->state = DLM_RECO_NODE_DATA_REQUESTING;
575 
576 		mlog(0, "%s: Requesting lock info from node %u\n", dlm->name,
577 		     ndata->node_num);
578 
579 		if (ndata->node_num == dlm->node_num) {
580 			ndata->state = DLM_RECO_NODE_DATA_DONE;
581 			continue;
582 		}
583 
584 		do {
585 			status = dlm_request_all_locks(dlm, ndata->node_num,
586 						       dead_node);
587 			if (status < 0) {
588 				mlog_errno(status);
589 				if (dlm_is_host_down(status)) {
590 					/* node died, ignore it for recovery */
591 					status = 0;
592 					ndata->state = DLM_RECO_NODE_DATA_DEAD;
593 					/* wait for the domain map to catch up
594 					 * with the network state. */
595 					wait_event_timeout(dlm->dlm_reco_thread_wq,
596 							   dlm_is_node_dead(dlm,
597 								ndata->node_num),
598 							   msecs_to_jiffies(1000));
599 					mlog(0, "waited 1 sec for %u, "
600 					     "dead? %s\n", ndata->node_num,
601 					     dlm_is_node_dead(dlm, ndata->node_num) ?
602 					     "yes" : "no");
603 				} else {
604 					/* -ENOMEM on the other node */
605 					mlog(0, "%s: node %u returned "
606 					     "%d during recovery, retrying "
607 					     "after a short wait\n",
608 					     dlm->name, ndata->node_num,
609 					     status);
610 					msleep(100);
611 				}
612 			}
613 		} while (status != 0);
614 
615 		spin_lock(&dlm_reco_state_lock);
616 		switch (ndata->state) {
617 			case DLM_RECO_NODE_DATA_INIT:
618 			case DLM_RECO_NODE_DATA_FINALIZE_SENT:
619 			case DLM_RECO_NODE_DATA_REQUESTED:
620 				BUG();
621 				break;
622 			case DLM_RECO_NODE_DATA_DEAD:
623 				mlog(0, "node %u died after requesting "
624 				     "recovery info for node %u\n",
625 				     ndata->node_num, dead_node);
626 				/* fine.  don't need this node's info.
627 				 * continue without it. */
628 				break;
629 			case DLM_RECO_NODE_DATA_REQUESTING:
630 				ndata->state = DLM_RECO_NODE_DATA_REQUESTED;
631 				mlog(0, "now receiving recovery data from "
632 				     "node %u for dead node %u\n",
633 				     ndata->node_num, dead_node);
634 				break;
635 			case DLM_RECO_NODE_DATA_RECEIVING:
636 				mlog(0, "already receiving recovery data from "
637 				     "node %u for dead node %u\n",
638 				     ndata->node_num, dead_node);
639 				break;
640 			case DLM_RECO_NODE_DATA_DONE:
641 				mlog(0, "already DONE receiving recovery data "
642 				     "from node %u for dead node %u\n",
643 				     ndata->node_num, dead_node);
644 				break;
645 		}
646 		spin_unlock(&dlm_reco_state_lock);
647 	}
648 
649 	mlog(0, "%s: Done requesting all lock info\n", dlm->name);
650 
651 	/* nodes should be sending reco data now
652 	 * just need to wait */
653 
654 	while (1) {
655 		/* check all the nodes now to see if we are
656 		 * done, or if anyone died */
657 		all_nodes_done = 1;
658 		spin_lock(&dlm_reco_state_lock);
659 		list_for_each_entry(ndata, &dlm->reco.node_data, list) {
660 			mlog(0, "checking recovery state of node %u\n",
661 			     ndata->node_num);
662 			switch (ndata->state) {
663 				case DLM_RECO_NODE_DATA_INIT:
664 				case DLM_RECO_NODE_DATA_REQUESTING:
665 					mlog(ML_ERROR, "bad ndata state for "
666 					     "node %u: state=%d\n",
667 					     ndata->node_num, ndata->state);
668 					BUG();
669 					break;
670 				case DLM_RECO_NODE_DATA_DEAD:
671 					mlog(0, "node %u died after "
672 					     "requesting recovery info for "
673 					     "node %u\n", ndata->node_num,
674 					     dead_node);
675 					break;
676 				case DLM_RECO_NODE_DATA_RECEIVING:
677 				case DLM_RECO_NODE_DATA_REQUESTED:
678 					mlog(0, "%s: node %u still in state %s\n",
679 					     dlm->name, ndata->node_num,
680 					     ndata->state==DLM_RECO_NODE_DATA_RECEIVING ?
681 					     "receiving" : "requested");
682 					all_nodes_done = 0;
683 					break;
684 				case DLM_RECO_NODE_DATA_DONE:
685 					mlog(0, "%s: node %u state is done\n",
686 					     dlm->name, ndata->node_num);
687 					break;
688 				case DLM_RECO_NODE_DATA_FINALIZE_SENT:
689 					mlog(0, "%s: node %u state is finalize\n",
690 					     dlm->name, ndata->node_num);
691 					break;
692 			}
693 		}
694 		spin_unlock(&dlm_reco_state_lock);
695 
696 		mlog(0, "pass #%d, all_nodes_done?: %s\n", ++pass,
697 		     all_nodes_done?"yes":"no");
698 		if (all_nodes_done) {
699 			int ret;
700 
701 			/* all nodes are now in DLM_RECO_NODE_DATA_DONE state
702 	 		 * just send a finalize message to everyone and
703 	 		 * clean up */
704 			mlog(0, "all nodes are done! send finalize\n");
705 			ret = dlm_send_finalize_reco_message(dlm);
706 			if (ret < 0)
707 				mlog_errno(ret);
708 
709 			spin_lock(&dlm->spinlock);
710 			dlm_finish_local_lockres_recovery(dlm, dead_node,
711 							  dlm->node_num);
712 			spin_unlock(&dlm->spinlock);
713 			mlog(0, "should be done with recovery!\n");
714 
715 			mlog(0, "finishing recovery of %s at %lu, "
716 			     "dead=%u, this=%u, new=%u\n", dlm->name,
717 			     jiffies, dlm->reco.dead_node,
718 			     dlm->node_num, dlm->reco.new_master);
719 			destroy = 1;
720 			status = 0;
721 			/* rescan everything marked dirty along the way */
722 			dlm_kick_thread(dlm, NULL);
723 			break;
724 		}
725 		/* wait to be signalled, with periodic timeout
726 		 * to check for node death */
727 		wait_event_interruptible_timeout(dlm->dlm_reco_thread_wq,
728 					 kthread_should_stop(),
729 					 msecs_to_jiffies(DLM_RECO_THREAD_TIMEOUT_MS));
730 
731 	}
732 
733 	if (destroy)
734 		dlm_destroy_recovery_area(dlm, dead_node);
735 
736 	return status;
737 }
738 
739 static int dlm_init_recovery_area(struct dlm_ctxt *dlm, u8 dead_node)
740 {
741 	int num=0;
742 	struct dlm_reco_node_data *ndata;
743 
744 	spin_lock(&dlm->spinlock);
745 	memcpy(dlm->reco.node_map, dlm->domain_map, sizeof(dlm->domain_map));
746 	/* nodes can only be removed (by dying) after dropping
747 	 * this lock, and death will be trapped later, so this should do */
748 	spin_unlock(&dlm->spinlock);
749 
750 	while (1) {
751 		num = find_next_bit (dlm->reco.node_map, O2NM_MAX_NODES, num);
752 		if (num >= O2NM_MAX_NODES) {
753 			break;
754 		}
755 		BUG_ON(num == dead_node);
756 
757 		ndata = kzalloc(sizeof(*ndata), GFP_NOFS);
758 		if (!ndata) {
759 			dlm_destroy_recovery_area(dlm, dead_node);
760 			return -ENOMEM;
761 		}
762 		ndata->node_num = num;
763 		ndata->state = DLM_RECO_NODE_DATA_INIT;
764 		spin_lock(&dlm_reco_state_lock);
765 		list_add_tail(&ndata->list, &dlm->reco.node_data);
766 		spin_unlock(&dlm_reco_state_lock);
767 		num++;
768 	}
769 
770 	return 0;
771 }
772 
773 static void dlm_destroy_recovery_area(struct dlm_ctxt *dlm, u8 dead_node)
774 {
775 	struct dlm_reco_node_data *ndata, *next;
776 	LIST_HEAD(tmplist);
777 
778 	spin_lock(&dlm_reco_state_lock);
779 	list_splice_init(&dlm->reco.node_data, &tmplist);
780 	spin_unlock(&dlm_reco_state_lock);
781 
782 	list_for_each_entry_safe(ndata, next, &tmplist, list) {
783 		list_del_init(&ndata->list);
784 		kfree(ndata);
785 	}
786 }
787 
788 static int dlm_request_all_locks(struct dlm_ctxt *dlm, u8 request_from,
789 				 u8 dead_node)
790 {
791 	struct dlm_lock_request lr;
792 	enum dlm_status ret;
793 
794 	mlog(0, "\n");
795 
796 
797 	mlog(0, "dlm_request_all_locks: dead node is %u, sending request "
798 		  "to %u\n", dead_node, request_from);
799 
800 	memset(&lr, 0, sizeof(lr));
801 	lr.node_idx = dlm->node_num;
802 	lr.dead_node = dead_node;
803 
804 	// send message
805 	ret = DLM_NOLOCKMGR;
806 	ret = o2net_send_message(DLM_LOCK_REQUEST_MSG, dlm->key,
807 				 &lr, sizeof(lr), request_from, NULL);
808 
809 	/* negative status is handled by caller */
810 	if (ret < 0)
811 		mlog(ML_ERROR, "%s: Error %d send LOCK_REQUEST to node %u "
812 		     "to recover dead node %u\n", dlm->name, ret,
813 		     request_from, dead_node);
814 	// return from here, then
815 	// sleep until all received or error
816 	return ret;
817 
818 }
819 
820 int dlm_request_all_locks_handler(struct o2net_msg *msg, u32 len, void *data,
821 				  void **ret_data)
822 {
823 	struct dlm_ctxt *dlm = data;
824 	struct dlm_lock_request *lr = (struct dlm_lock_request *)msg->buf;
825 	char *buf = NULL;
826 	struct dlm_work_item *item = NULL;
827 
828 	if (!dlm_grab(dlm))
829 		return -EINVAL;
830 
831 	if (lr->dead_node != dlm->reco.dead_node) {
832 		mlog(ML_ERROR, "%s: node %u sent dead_node=%u, but local "
833 		     "dead_node is %u\n", dlm->name, lr->node_idx,
834 		     lr->dead_node, dlm->reco.dead_node);
835 		dlm_print_reco_node_status(dlm);
836 		/* this is a hack */
837 		dlm_put(dlm);
838 		return -ENOMEM;
839 	}
840 	BUG_ON(lr->dead_node != dlm->reco.dead_node);
841 
842 	item = kzalloc(sizeof(*item), GFP_NOFS);
843 	if (!item) {
844 		dlm_put(dlm);
845 		return -ENOMEM;
846 	}
847 
848 	/* this will get freed by dlm_request_all_locks_worker */
849 	buf = (char *) __get_free_page(GFP_NOFS);
850 	if (!buf) {
851 		kfree(item);
852 		dlm_put(dlm);
853 		return -ENOMEM;
854 	}
855 
856 	/* queue up work for dlm_request_all_locks_worker */
857 	dlm_grab(dlm);  /* get an extra ref for the work item */
858 	dlm_init_work_item(dlm, item, dlm_request_all_locks_worker, buf);
859 	item->u.ral.reco_master = lr->node_idx;
860 	item->u.ral.dead_node = lr->dead_node;
861 	spin_lock(&dlm->work_lock);
862 	list_add_tail(&item->list, &dlm->work_list);
863 	spin_unlock(&dlm->work_lock);
864 	queue_work(dlm->dlm_worker, &dlm->dispatched_work);
865 
866 	dlm_put(dlm);
867 	return 0;
868 }
869 
870 static void dlm_request_all_locks_worker(struct dlm_work_item *item, void *data)
871 {
872 	struct dlm_migratable_lockres *mres;
873 	struct dlm_lock_resource *res;
874 	struct dlm_ctxt *dlm;
875 	LIST_HEAD(resources);
876 	int ret;
877 	u8 dead_node, reco_master;
878 	int skip_all_done = 0;
879 
880 	dlm = item->dlm;
881 	dead_node = item->u.ral.dead_node;
882 	reco_master = item->u.ral.reco_master;
883 	mres = (struct dlm_migratable_lockres *)data;
884 
885 	mlog(0, "%s: recovery worker started, dead=%u, master=%u\n",
886 	     dlm->name, dead_node, reco_master);
887 
888 	if (dead_node != dlm->reco.dead_node ||
889 	    reco_master != dlm->reco.new_master) {
890 		/* worker could have been created before the recovery master
891 		 * died.  if so, do not continue, but do not error. */
892 		if (dlm->reco.new_master == O2NM_INVALID_NODE_NUM) {
893 			mlog(ML_NOTICE, "%s: will not send recovery state, "
894 			     "recovery master %u died, thread=(dead=%u,mas=%u)"
895 			     " current=(dead=%u,mas=%u)\n", dlm->name,
896 			     reco_master, dead_node, reco_master,
897 			     dlm->reco.dead_node, dlm->reco.new_master);
898 		} else {
899 			mlog(ML_NOTICE, "%s: reco state invalid: reco(dead=%u, "
900 			     "master=%u), request(dead=%u, master=%u)\n",
901 			     dlm->name, dlm->reco.dead_node,
902 			     dlm->reco.new_master, dead_node, reco_master);
903 		}
904 		goto leave;
905 	}
906 
907 	/* lock resources should have already been moved to the
908  	 * dlm->reco.resources list.  now move items from that list
909  	 * to a temp list if the dead owner matches.  note that the
910 	 * whole cluster recovers only one node at a time, so we
911 	 * can safely move UNKNOWN lock resources for each recovery
912 	 * session. */
913 	dlm_move_reco_locks_to_list(dlm, &resources, dead_node);
914 
915 	/* now we can begin blasting lockreses without the dlm lock */
916 
917 	/* any errors returned will be due to the new_master dying,
918 	 * the dlm_reco_thread should detect this */
919 	list_for_each_entry(res, &resources, recovering) {
920 		ret = dlm_send_one_lockres(dlm, res, mres, reco_master,
921 				   	DLM_MRES_RECOVERY);
922 		if (ret < 0) {
923 			mlog(ML_ERROR, "%s: node %u went down while sending "
924 			     "recovery state for dead node %u, ret=%d\n", dlm->name,
925 			     reco_master, dead_node, ret);
926 			skip_all_done = 1;
927 			break;
928 		}
929 	}
930 
931 	/* move the resources back to the list */
932 	spin_lock(&dlm->spinlock);
933 	list_splice_init(&resources, &dlm->reco.resources);
934 	spin_unlock(&dlm->spinlock);
935 
936 	if (!skip_all_done) {
937 		ret = dlm_send_all_done_msg(dlm, dead_node, reco_master);
938 		if (ret < 0) {
939 			mlog(ML_ERROR, "%s: node %u went down while sending "
940 			     "recovery all-done for dead node %u, ret=%d\n",
941 			     dlm->name, reco_master, dead_node, ret);
942 		}
943 	}
944 leave:
945 	free_page((unsigned long)data);
946 }
947 
948 
949 static int dlm_send_all_done_msg(struct dlm_ctxt *dlm, u8 dead_node, u8 send_to)
950 {
951 	int ret, tmpret;
952 	struct dlm_reco_data_done done_msg;
953 
954 	memset(&done_msg, 0, sizeof(done_msg));
955 	done_msg.node_idx = dlm->node_num;
956 	done_msg.dead_node = dead_node;
957 	mlog(0, "sending DATA DONE message to %u, "
958 	     "my node=%u, dead node=%u\n", send_to, done_msg.node_idx,
959 	     done_msg.dead_node);
960 
961 	ret = o2net_send_message(DLM_RECO_DATA_DONE_MSG, dlm->key, &done_msg,
962 				 sizeof(done_msg), send_to, &tmpret);
963 	if (ret < 0) {
964 		mlog(ML_ERROR, "%s: Error %d send RECO_DATA_DONE to node %u "
965 		     "to recover dead node %u\n", dlm->name, ret, send_to,
966 		     dead_node);
967 		if (!dlm_is_host_down(ret)) {
968 			BUG();
969 		}
970 	} else
971 		ret = tmpret;
972 	return ret;
973 }
974 
975 
976 int dlm_reco_data_done_handler(struct o2net_msg *msg, u32 len, void *data,
977 			       void **ret_data)
978 {
979 	struct dlm_ctxt *dlm = data;
980 	struct dlm_reco_data_done *done = (struct dlm_reco_data_done *)msg->buf;
981 	struct dlm_reco_node_data *ndata = NULL;
982 	int ret = -EINVAL;
983 
984 	if (!dlm_grab(dlm))
985 		return -EINVAL;
986 
987 	mlog(0, "got DATA DONE: dead_node=%u, reco.dead_node=%u, "
988 	     "node_idx=%u, this node=%u\n", done->dead_node,
989 	     dlm->reco.dead_node, done->node_idx, dlm->node_num);
990 
991 	mlog_bug_on_msg((done->dead_node != dlm->reco.dead_node),
992 			"Got DATA DONE: dead_node=%u, reco.dead_node=%u, "
993 			"node_idx=%u, this node=%u\n", done->dead_node,
994 			dlm->reco.dead_node, done->node_idx, dlm->node_num);
995 
996 	spin_lock(&dlm_reco_state_lock);
997 	list_for_each_entry(ndata, &dlm->reco.node_data, list) {
998 		if (ndata->node_num != done->node_idx)
999 			continue;
1000 
1001 		switch (ndata->state) {
1002 			/* should have moved beyond INIT but not to FINALIZE yet */
1003 			case DLM_RECO_NODE_DATA_INIT:
1004 			case DLM_RECO_NODE_DATA_DEAD:
1005 			case DLM_RECO_NODE_DATA_FINALIZE_SENT:
1006 				mlog(ML_ERROR, "bad ndata state for node %u:"
1007 				     " state=%d\n", ndata->node_num,
1008 				     ndata->state);
1009 				BUG();
1010 				break;
1011 			/* these states are possible at this point, anywhere along
1012 			 * the line of recovery */
1013 			case DLM_RECO_NODE_DATA_DONE:
1014 			case DLM_RECO_NODE_DATA_RECEIVING:
1015 			case DLM_RECO_NODE_DATA_REQUESTED:
1016 			case DLM_RECO_NODE_DATA_REQUESTING:
1017 				mlog(0, "node %u is DONE sending "
1018 					  "recovery data!\n",
1019 					  ndata->node_num);
1020 
1021 				ndata->state = DLM_RECO_NODE_DATA_DONE;
1022 				ret = 0;
1023 				break;
1024 		}
1025 	}
1026 	spin_unlock(&dlm_reco_state_lock);
1027 
1028 	/* wake the recovery thread, some node is done */
1029 	if (!ret)
1030 		dlm_kick_recovery_thread(dlm);
1031 
1032 	if (ret < 0)
1033 		mlog(ML_ERROR, "failed to find recovery node data for node "
1034 		     "%u\n", done->node_idx);
1035 	dlm_put(dlm);
1036 
1037 	mlog(0, "leaving reco data done handler, ret=%d\n", ret);
1038 	return ret;
1039 }
1040 
1041 static void dlm_move_reco_locks_to_list(struct dlm_ctxt *dlm,
1042 					struct list_head *list,
1043 				       	u8 dead_node)
1044 {
1045 	struct dlm_lock_resource *res, *next;
1046 	struct dlm_lock *lock;
1047 
1048 	spin_lock(&dlm->spinlock);
1049 	list_for_each_entry_safe(res, next, &dlm->reco.resources, recovering) {
1050 		/* always prune any $RECOVERY entries for dead nodes,
1051 		 * otherwise hangs can occur during later recovery */
1052 		if (dlm_is_recovery_lock(res->lockname.name,
1053 					 res->lockname.len)) {
1054 			spin_lock(&res->spinlock);
1055 			list_for_each_entry(lock, &res->granted, list) {
1056 				if (lock->ml.node == dead_node) {
1057 					mlog(0, "AHA! there was "
1058 					     "a $RECOVERY lock for dead "
1059 					     "node %u (%s)!\n",
1060 					     dead_node, dlm->name);
1061 					list_del_init(&lock->list);
1062 					dlm_lock_put(lock);
1063 					break;
1064 				}
1065 			}
1066 			spin_unlock(&res->spinlock);
1067 			continue;
1068 		}
1069 
1070 		if (res->owner == dead_node) {
1071 			mlog(0, "found lockres owned by dead node while "
1072 				  "doing recovery for node %u. sending it.\n",
1073 				  dead_node);
1074 			list_move_tail(&res->recovering, list);
1075 		} else if (res->owner == DLM_LOCK_RES_OWNER_UNKNOWN) {
1076 			mlog(0, "found UNKNOWN owner while doing recovery "
1077 				  "for node %u. sending it.\n", dead_node);
1078 			list_move_tail(&res->recovering, list);
1079 		}
1080 	}
1081 	spin_unlock(&dlm->spinlock);
1082 }
1083 
1084 static inline int dlm_num_locks_in_lockres(struct dlm_lock_resource *res)
1085 {
1086 	int total_locks = 0;
1087 	struct list_head *iter, *queue = &res->granted;
1088 	int i;
1089 
1090 	for (i=0; i<3; i++) {
1091 		list_for_each(iter, queue)
1092 			total_locks++;
1093 		queue++;
1094 	}
1095 	return total_locks;
1096 }
1097 
1098 
1099 static int dlm_send_mig_lockres_msg(struct dlm_ctxt *dlm,
1100 				      struct dlm_migratable_lockres *mres,
1101 				      u8 send_to,
1102 				      struct dlm_lock_resource *res,
1103 				      int total_locks)
1104 {
1105 	u64 mig_cookie = be64_to_cpu(mres->mig_cookie);
1106 	int mres_total_locks = be32_to_cpu(mres->total_locks);
1107 	int sz, ret = 0, status = 0;
1108 	u8 orig_flags = mres->flags,
1109 	   orig_master = mres->master;
1110 
1111 	BUG_ON(mres->num_locks > DLM_MAX_MIGRATABLE_LOCKS);
1112 	if (!mres->num_locks)
1113 		return 0;
1114 
1115 	sz = sizeof(struct dlm_migratable_lockres) +
1116 		(mres->num_locks * sizeof(struct dlm_migratable_lock));
1117 
1118 	/* add an all-done flag if we reached the last lock */
1119 	orig_flags = mres->flags;
1120 	BUG_ON(total_locks > mres_total_locks);
1121 	if (total_locks == mres_total_locks)
1122 		mres->flags |= DLM_MRES_ALL_DONE;
1123 
1124 	mlog(0, "%s:%.*s: sending mig lockres (%s) to %u\n",
1125 	     dlm->name, res->lockname.len, res->lockname.name,
1126 	     orig_flags & DLM_MRES_MIGRATION ? "migration" : "recovery",
1127 	     send_to);
1128 
1129 	/* send it */
1130 	ret = o2net_send_message(DLM_MIG_LOCKRES_MSG, dlm->key, mres,
1131 				 sz, send_to, &status);
1132 	if (ret < 0) {
1133 		/* XXX: negative status is not handled.
1134 		 * this will end up killing this node. */
1135 		mlog(ML_ERROR, "%s: res %.*s, Error %d send MIG_LOCKRES to "
1136 		     "node %u (%s)\n", dlm->name, mres->lockname_len,
1137 		     mres->lockname, ret, send_to,
1138 		     (orig_flags & DLM_MRES_MIGRATION ?
1139 		      "migration" : "recovery"));
1140 	} else {
1141 		/* might get an -ENOMEM back here */
1142 		ret = status;
1143 		if (ret < 0) {
1144 			mlog_errno(ret);
1145 
1146 			if (ret == -EFAULT) {
1147 				mlog(ML_ERROR, "node %u told me to kill "
1148 				     "myself!\n", send_to);
1149 				BUG();
1150 			}
1151 		}
1152 	}
1153 
1154 	/* zero and reinit the message buffer */
1155 	dlm_init_migratable_lockres(mres, res->lockname.name,
1156 				    res->lockname.len, mres_total_locks,
1157 				    mig_cookie, orig_flags, orig_master);
1158 	return ret;
1159 }
1160 
1161 static void dlm_init_migratable_lockres(struct dlm_migratable_lockres *mres,
1162 					const char *lockname, int namelen,
1163 					int total_locks, u64 cookie,
1164 					u8 flags, u8 master)
1165 {
1166 	/* mres here is one full page */
1167 	clear_page(mres);
1168 	mres->lockname_len = namelen;
1169 	memcpy(mres->lockname, lockname, namelen);
1170 	mres->num_locks = 0;
1171 	mres->total_locks = cpu_to_be32(total_locks);
1172 	mres->mig_cookie = cpu_to_be64(cookie);
1173 	mres->flags = flags;
1174 	mres->master = master;
1175 }
1176 
1177 static void dlm_prepare_lvb_for_migration(struct dlm_lock *lock,
1178 					  struct dlm_migratable_lockres *mres,
1179 					  int queue)
1180 {
1181 	if (!lock->lksb)
1182 	       return;
1183 
1184 	/* Ignore lvb in all locks in the blocked list */
1185 	if (queue == DLM_BLOCKED_LIST)
1186 		return;
1187 
1188 	/* Only consider lvbs in locks with granted EX or PR lock levels */
1189 	if (lock->ml.type != LKM_EXMODE && lock->ml.type != LKM_PRMODE)
1190 		return;
1191 
1192 	if (dlm_lvb_is_empty(mres->lvb)) {
1193 		memcpy(mres->lvb, lock->lksb->lvb, DLM_LVB_LEN);
1194 		return;
1195 	}
1196 
1197 	/* Ensure the lvb copied for migration matches in other valid locks */
1198 	if (!memcmp(mres->lvb, lock->lksb->lvb, DLM_LVB_LEN))
1199 		return;
1200 
1201 	mlog(ML_ERROR, "Mismatched lvb in lock cookie=%u:%llu, name=%.*s, "
1202 	     "node=%u\n",
1203 	     dlm_get_lock_cookie_node(be64_to_cpu(lock->ml.cookie)),
1204 	     dlm_get_lock_cookie_seq(be64_to_cpu(lock->ml.cookie)),
1205 	     lock->lockres->lockname.len, lock->lockres->lockname.name,
1206 	     lock->ml.node);
1207 	dlm_print_one_lock_resource(lock->lockres);
1208 	BUG();
1209 }
1210 
1211 /* returns 1 if this lock fills the network structure,
1212  * 0 otherwise */
1213 static int dlm_add_lock_to_array(struct dlm_lock *lock,
1214 				 struct dlm_migratable_lockres *mres, int queue)
1215 {
1216 	struct dlm_migratable_lock *ml;
1217 	int lock_num = mres->num_locks;
1218 
1219 	ml = &(mres->ml[lock_num]);
1220 	ml->cookie = lock->ml.cookie;
1221 	ml->type = lock->ml.type;
1222 	ml->convert_type = lock->ml.convert_type;
1223 	ml->highest_blocked = lock->ml.highest_blocked;
1224 	ml->list = queue;
1225 	if (lock->lksb) {
1226 		ml->flags = lock->lksb->flags;
1227 		dlm_prepare_lvb_for_migration(lock, mres, queue);
1228 	}
1229 	ml->node = lock->ml.node;
1230 	mres->num_locks++;
1231 	/* we reached the max, send this network message */
1232 	if (mres->num_locks == DLM_MAX_MIGRATABLE_LOCKS)
1233 		return 1;
1234 	return 0;
1235 }
1236 
1237 static void dlm_add_dummy_lock(struct dlm_ctxt *dlm,
1238 			       struct dlm_migratable_lockres *mres)
1239 {
1240 	struct dlm_lock dummy;
1241 	memset(&dummy, 0, sizeof(dummy));
1242 	dummy.ml.cookie = 0;
1243 	dummy.ml.type = LKM_IVMODE;
1244 	dummy.ml.convert_type = LKM_IVMODE;
1245 	dummy.ml.highest_blocked = LKM_IVMODE;
1246 	dummy.lksb = NULL;
1247 	dummy.ml.node = dlm->node_num;
1248 	dlm_add_lock_to_array(&dummy, mres, DLM_BLOCKED_LIST);
1249 }
1250 
1251 static inline int dlm_is_dummy_lock(struct dlm_ctxt *dlm,
1252 				    struct dlm_migratable_lock *ml,
1253 				    u8 *nodenum)
1254 {
1255 	if (unlikely(ml->cookie == 0 &&
1256 	    ml->type == LKM_IVMODE &&
1257 	    ml->convert_type == LKM_IVMODE &&
1258 	    ml->highest_blocked == LKM_IVMODE &&
1259 	    ml->list == DLM_BLOCKED_LIST)) {
1260 		*nodenum = ml->node;
1261 		return 1;
1262 	}
1263 	return 0;
1264 }
1265 
1266 int dlm_send_one_lockres(struct dlm_ctxt *dlm, struct dlm_lock_resource *res,
1267 			 struct dlm_migratable_lockres *mres,
1268 			 u8 send_to, u8 flags)
1269 {
1270 	struct list_head *queue;
1271 	int total_locks, i;
1272 	u64 mig_cookie = 0;
1273 	struct dlm_lock *lock;
1274 	int ret = 0;
1275 
1276 	BUG_ON(!(flags & (DLM_MRES_RECOVERY|DLM_MRES_MIGRATION)));
1277 
1278 	mlog(0, "sending to %u\n", send_to);
1279 
1280 	total_locks = dlm_num_locks_in_lockres(res);
1281 	if (total_locks > DLM_MAX_MIGRATABLE_LOCKS) {
1282 		/* rare, but possible */
1283 		mlog(0, "argh.  lockres has %d locks.  this will "
1284 			  "require more than one network packet to "
1285 			  "migrate\n", total_locks);
1286 		mig_cookie = dlm_get_next_mig_cookie();
1287 	}
1288 
1289 	dlm_init_migratable_lockres(mres, res->lockname.name,
1290 				    res->lockname.len, total_locks,
1291 				    mig_cookie, flags, res->owner);
1292 
1293 	total_locks = 0;
1294 	for (i=DLM_GRANTED_LIST; i<=DLM_BLOCKED_LIST; i++) {
1295 		queue = dlm_list_idx_to_ptr(res, i);
1296 		list_for_each_entry(lock, queue, list) {
1297 			/* add another lock. */
1298 			total_locks++;
1299 			if (!dlm_add_lock_to_array(lock, mres, i))
1300 				continue;
1301 
1302 			/* this filled the lock message,
1303 			 * we must send it immediately. */
1304 			ret = dlm_send_mig_lockres_msg(dlm, mres, send_to,
1305 						       res, total_locks);
1306 			if (ret < 0)
1307 				goto error;
1308 		}
1309 	}
1310 	if (total_locks == 0) {
1311 		/* send a dummy lock to indicate a mastery reference only */
1312 		mlog(0, "%s:%.*s: sending dummy lock to %u, %s\n",
1313 		     dlm->name, res->lockname.len, res->lockname.name,
1314 		     send_to, flags & DLM_MRES_RECOVERY ? "recovery" :
1315 		     "migration");
1316 		dlm_add_dummy_lock(dlm, mres);
1317 	}
1318 	/* flush any remaining locks */
1319 	ret = dlm_send_mig_lockres_msg(dlm, mres, send_to, res, total_locks);
1320 	if (ret < 0)
1321 		goto error;
1322 	return ret;
1323 
1324 error:
1325 	mlog(ML_ERROR, "%s: dlm_send_mig_lockres_msg returned %d\n",
1326 	     dlm->name, ret);
1327 	if (!dlm_is_host_down(ret))
1328 		BUG();
1329 	mlog(0, "%s: node %u went down while sending %s "
1330 	     "lockres %.*s\n", dlm->name, send_to,
1331 	     flags & DLM_MRES_RECOVERY ?  "recovery" : "migration",
1332 	     res->lockname.len, res->lockname.name);
1333 	return ret;
1334 }
1335 
1336 
1337 
1338 /*
1339  * this message will contain no more than one page worth of
1340  * recovery data, and it will work on only one lockres.
1341  * there may be many locks in this page, and we may need to wait
1342  * for additional packets to complete all the locks (rare, but
1343  * possible).
1344  */
1345 /*
1346  * NOTE: the allocation error cases here are scary
1347  * we really cannot afford to fail an alloc in recovery
1348  * do we spin?  returning an error only delays the problem really
1349  */
1350 
1351 int dlm_mig_lockres_handler(struct o2net_msg *msg, u32 len, void *data,
1352 			    void **ret_data)
1353 {
1354 	struct dlm_ctxt *dlm = data;
1355 	struct dlm_migratable_lockres *mres =
1356 		(struct dlm_migratable_lockres *)msg->buf;
1357 	int ret = 0;
1358 	u8 real_master;
1359 	u8 extra_refs = 0;
1360 	char *buf = NULL;
1361 	struct dlm_work_item *item = NULL;
1362 	struct dlm_lock_resource *res = NULL;
1363 
1364 	if (!dlm_grab(dlm))
1365 		return -EINVAL;
1366 
1367 	BUG_ON(!(mres->flags & (DLM_MRES_RECOVERY|DLM_MRES_MIGRATION)));
1368 
1369 	real_master = mres->master;
1370 	if (real_master == DLM_LOCK_RES_OWNER_UNKNOWN) {
1371 		/* cannot migrate a lockres with no master */
1372 		BUG_ON(!(mres->flags & DLM_MRES_RECOVERY));
1373 	}
1374 
1375 	mlog(0, "%s message received from node %u\n",
1376 		  (mres->flags & DLM_MRES_RECOVERY) ?
1377 		  "recovery" : "migration", mres->master);
1378 	if (mres->flags & DLM_MRES_ALL_DONE)
1379 		mlog(0, "all done flag.  all lockres data received!\n");
1380 
1381 	ret = -ENOMEM;
1382 	buf = kmalloc(be16_to_cpu(msg->data_len), GFP_NOFS);
1383 	item = kzalloc(sizeof(*item), GFP_NOFS);
1384 	if (!buf || !item)
1385 		goto leave;
1386 
1387 	/* lookup the lock to see if we have a secondary queue for this
1388 	 * already...  just add the locks in and this will have its owner
1389 	 * and RECOVERY flag changed when it completes. */
1390 	res = dlm_lookup_lockres(dlm, mres->lockname, mres->lockname_len);
1391 	if (res) {
1392 	 	/* this will get a ref on res */
1393 		/* mark it as recovering/migrating and hash it */
1394 		spin_lock(&res->spinlock);
1395 		if (mres->flags & DLM_MRES_RECOVERY) {
1396 			res->state |= DLM_LOCK_RES_RECOVERING;
1397 		} else {
1398 			if (res->state & DLM_LOCK_RES_MIGRATING) {
1399 				/* this is at least the second
1400 				 * lockres message */
1401 				mlog(0, "lock %.*s is already migrating\n",
1402 					  mres->lockname_len,
1403 					  mres->lockname);
1404 			} else if (res->state & DLM_LOCK_RES_RECOVERING) {
1405 				/* caller should BUG */
1406 				mlog(ML_ERROR, "node is attempting to migrate "
1407 				     "lock %.*s, but marked as recovering!\n",
1408 				     mres->lockname_len, mres->lockname);
1409 				ret = -EFAULT;
1410 				spin_unlock(&res->spinlock);
1411 				goto leave;
1412 			}
1413 			res->state |= DLM_LOCK_RES_MIGRATING;
1414 		}
1415 		spin_unlock(&res->spinlock);
1416 	} else {
1417 		/* need to allocate, just like if it was
1418 		 * mastered here normally  */
1419 		res = dlm_new_lockres(dlm, mres->lockname, mres->lockname_len);
1420 		if (!res)
1421 			goto leave;
1422 
1423 		/* to match the ref that we would have gotten if
1424 		 * dlm_lookup_lockres had succeeded */
1425 		dlm_lockres_get(res);
1426 
1427 		/* mark it as recovering/migrating and hash it */
1428 		if (mres->flags & DLM_MRES_RECOVERY)
1429 			res->state |= DLM_LOCK_RES_RECOVERING;
1430 		else
1431 			res->state |= DLM_LOCK_RES_MIGRATING;
1432 
1433 		spin_lock(&dlm->spinlock);
1434 		__dlm_insert_lockres(dlm, res);
1435 		spin_unlock(&dlm->spinlock);
1436 
1437 		/* Add an extra ref for this lock-less lockres lest the
1438 		 * dlm_thread purges it before we get the chance to add
1439 		 * locks to it */
1440 		dlm_lockres_get(res);
1441 
1442 		/* There are three refs that need to be put.
1443 		 * 1. Taken above.
1444 		 * 2. kref_init in dlm_new_lockres()->dlm_init_lockres().
1445 		 * 3. dlm_lookup_lockres()
1446 		 * The first one is handled at the end of this function. The
1447 		 * other two are handled in the worker thread after locks have
1448 		 * been attached. Yes, we don't wait for purge time to match
1449 		 * kref_init. The lockres will still have atleast one ref
1450 		 * added because it is in the hash __dlm_insert_lockres() */
1451 		extra_refs++;
1452 
1453 		/* now that the new lockres is inserted,
1454 		 * make it usable by other processes */
1455 		spin_lock(&res->spinlock);
1456 		res->state &= ~DLM_LOCK_RES_IN_PROGRESS;
1457 		spin_unlock(&res->spinlock);
1458 		wake_up(&res->wq);
1459 	}
1460 
1461 	/* at this point we have allocated everything we need,
1462 	 * and we have a hashed lockres with an extra ref and
1463 	 * the proper res->state flags. */
1464 	ret = 0;
1465 	spin_lock(&res->spinlock);
1466 	/* drop this either when master requery finds a different master
1467 	 * or when a lock is added by the recovery worker */
1468 	dlm_lockres_grab_inflight_ref(dlm, res);
1469 	if (mres->master == DLM_LOCK_RES_OWNER_UNKNOWN) {
1470 		/* migration cannot have an unknown master */
1471 		BUG_ON(!(mres->flags & DLM_MRES_RECOVERY));
1472 		mlog(0, "recovery has passed me a lockres with an "
1473 			  "unknown owner.. will need to requery: "
1474 			  "%.*s\n", mres->lockname_len, mres->lockname);
1475 	} else {
1476 		/* take a reference now to pin the lockres, drop it
1477 		 * when locks are added in the worker */
1478 		dlm_change_lockres_owner(dlm, res, dlm->node_num);
1479 	}
1480 	spin_unlock(&res->spinlock);
1481 
1482 	/* queue up work for dlm_mig_lockres_worker */
1483 	dlm_grab(dlm);  /* get an extra ref for the work item */
1484 	memcpy(buf, msg->buf, be16_to_cpu(msg->data_len));  /* copy the whole message */
1485 	dlm_init_work_item(dlm, item, dlm_mig_lockres_worker, buf);
1486 	item->u.ml.lockres = res; /* already have a ref */
1487 	item->u.ml.real_master = real_master;
1488 	item->u.ml.extra_ref = extra_refs;
1489 	spin_lock(&dlm->work_lock);
1490 	list_add_tail(&item->list, &dlm->work_list);
1491 	spin_unlock(&dlm->work_lock);
1492 	queue_work(dlm->dlm_worker, &dlm->dispatched_work);
1493 
1494 leave:
1495 	/* One extra ref taken needs to be put here */
1496 	if (extra_refs)
1497 		dlm_lockres_put(res);
1498 
1499 	dlm_put(dlm);
1500 	if (ret < 0) {
1501 		kfree(buf);
1502 		kfree(item);
1503 		mlog_errno(ret);
1504 	}
1505 
1506 	return ret;
1507 }
1508 
1509 
1510 static void dlm_mig_lockres_worker(struct dlm_work_item *item, void *data)
1511 {
1512 	struct dlm_ctxt *dlm;
1513 	struct dlm_migratable_lockres *mres;
1514 	int ret = 0;
1515 	struct dlm_lock_resource *res;
1516 	u8 real_master;
1517 	u8 extra_ref;
1518 
1519 	dlm = item->dlm;
1520 	mres = (struct dlm_migratable_lockres *)data;
1521 
1522 	res = item->u.ml.lockres;
1523 	real_master = item->u.ml.real_master;
1524 	extra_ref = item->u.ml.extra_ref;
1525 
1526 	if (real_master == DLM_LOCK_RES_OWNER_UNKNOWN) {
1527 		/* this case is super-rare. only occurs if
1528 		 * node death happens during migration. */
1529 again:
1530 		ret = dlm_lockres_master_requery(dlm, res, &real_master);
1531 		if (ret < 0) {
1532 			mlog(0, "dlm_lockres_master_requery ret=%d\n",
1533 				  ret);
1534 			goto again;
1535 		}
1536 		if (real_master == DLM_LOCK_RES_OWNER_UNKNOWN) {
1537 			mlog(0, "lockres %.*s not claimed.  "
1538 				   "this node will take it.\n",
1539 				   res->lockname.len, res->lockname.name);
1540 		} else {
1541 			spin_lock(&res->spinlock);
1542 			dlm_lockres_drop_inflight_ref(dlm, res);
1543 			spin_unlock(&res->spinlock);
1544 			mlog(0, "master needs to respond to sender "
1545 				  "that node %u still owns %.*s\n",
1546 				  real_master, res->lockname.len,
1547 				  res->lockname.name);
1548 			/* cannot touch this lockres */
1549 			goto leave;
1550 		}
1551 	}
1552 
1553 	ret = dlm_process_recovery_data(dlm, res, mres);
1554 	if (ret < 0)
1555 		mlog(0, "dlm_process_recovery_data returned  %d\n", ret);
1556 	else
1557 		mlog(0, "dlm_process_recovery_data succeeded\n");
1558 
1559 	if ((mres->flags & (DLM_MRES_MIGRATION|DLM_MRES_ALL_DONE)) ==
1560 	                   (DLM_MRES_MIGRATION|DLM_MRES_ALL_DONE)) {
1561 		ret = dlm_finish_migration(dlm, res, mres->master);
1562 		if (ret < 0)
1563 			mlog_errno(ret);
1564 	}
1565 
1566 leave:
1567 	/* See comment in dlm_mig_lockres_handler() */
1568 	if (res) {
1569 		if (extra_ref)
1570 			dlm_lockres_put(res);
1571 		dlm_lockres_put(res);
1572 	}
1573 	kfree(data);
1574 }
1575 
1576 
1577 
1578 static int dlm_lockres_master_requery(struct dlm_ctxt *dlm,
1579 				      struct dlm_lock_resource *res,
1580 				      u8 *real_master)
1581 {
1582 	struct dlm_node_iter iter;
1583 	int nodenum;
1584 	int ret = 0;
1585 
1586 	*real_master = DLM_LOCK_RES_OWNER_UNKNOWN;
1587 
1588 	/* we only reach here if one of the two nodes in a
1589 	 * migration died while the migration was in progress.
1590 	 * at this point we need to requery the master.  we
1591 	 * know that the new_master got as far as creating
1592 	 * an mle on at least one node, but we do not know
1593 	 * if any nodes had actually cleared the mle and set
1594 	 * the master to the new_master.  the old master
1595 	 * is supposed to set the owner to UNKNOWN in the
1596 	 * event of a new_master death, so the only possible
1597 	 * responses that we can get from nodes here are
1598 	 * that the master is new_master, or that the master
1599 	 * is UNKNOWN.
1600 	 * if all nodes come back with UNKNOWN then we know
1601 	 * the lock needs remastering here.
1602 	 * if any node comes back with a valid master, check
1603 	 * to see if that master is the one that we are
1604 	 * recovering.  if so, then the new_master died and
1605 	 * we need to remaster this lock.  if not, then the
1606 	 * new_master survived and that node will respond to
1607 	 * other nodes about the owner.
1608 	 * if there is an owner, this node needs to dump this
1609 	 * lockres and alert the sender that this lockres
1610 	 * was rejected. */
1611 	spin_lock(&dlm->spinlock);
1612 	dlm_node_iter_init(dlm->domain_map, &iter);
1613 	spin_unlock(&dlm->spinlock);
1614 
1615 	while ((nodenum = dlm_node_iter_next(&iter)) >= 0) {
1616 		/* do not send to self */
1617 		if (nodenum == dlm->node_num)
1618 			continue;
1619 		ret = dlm_do_master_requery(dlm, res, nodenum, real_master);
1620 		if (ret < 0) {
1621 			mlog_errno(ret);
1622 			if (!dlm_is_host_down(ret))
1623 				BUG();
1624 			/* host is down, so answer for that node would be
1625 			 * DLM_LOCK_RES_OWNER_UNKNOWN.  continue. */
1626 		}
1627 		if (*real_master != DLM_LOCK_RES_OWNER_UNKNOWN) {
1628 			mlog(0, "lock master is %u\n", *real_master);
1629 			break;
1630 		}
1631 	}
1632 	return ret;
1633 }
1634 
1635 
1636 int dlm_do_master_requery(struct dlm_ctxt *dlm, struct dlm_lock_resource *res,
1637 			  u8 nodenum, u8 *real_master)
1638 {
1639 	int ret = -EINVAL;
1640 	struct dlm_master_requery req;
1641 	int status = DLM_LOCK_RES_OWNER_UNKNOWN;
1642 
1643 	memset(&req, 0, sizeof(req));
1644 	req.node_idx = dlm->node_num;
1645 	req.namelen = res->lockname.len;
1646 	memcpy(req.name, res->lockname.name, res->lockname.len);
1647 
1648 	ret = o2net_send_message(DLM_MASTER_REQUERY_MSG, dlm->key,
1649 				 &req, sizeof(req), nodenum, &status);
1650 	/* XXX: negative status not handled properly here. */
1651 	if (ret < 0)
1652 		mlog(ML_ERROR, "Error %d when sending message %u (key "
1653 		     "0x%x) to node %u\n", ret, DLM_MASTER_REQUERY_MSG,
1654 		     dlm->key, nodenum);
1655 	else {
1656 		BUG_ON(status < 0);
1657 		BUG_ON(status > DLM_LOCK_RES_OWNER_UNKNOWN);
1658 		*real_master = (u8) (status & 0xff);
1659 		mlog(0, "node %u responded to master requery with %u\n",
1660 			  nodenum, *real_master);
1661 		ret = 0;
1662 	}
1663 	return ret;
1664 }
1665 
1666 
1667 /* this function cannot error, so unless the sending
1668  * or receiving of the message failed, the owner can
1669  * be trusted */
1670 int dlm_master_requery_handler(struct o2net_msg *msg, u32 len, void *data,
1671 			       void **ret_data)
1672 {
1673 	struct dlm_ctxt *dlm = data;
1674 	struct dlm_master_requery *req = (struct dlm_master_requery *)msg->buf;
1675 	struct dlm_lock_resource *res = NULL;
1676 	unsigned int hash;
1677 	int master = DLM_LOCK_RES_OWNER_UNKNOWN;
1678 	u32 flags = DLM_ASSERT_MASTER_REQUERY;
1679 
1680 	if (!dlm_grab(dlm)) {
1681 		/* since the domain has gone away on this
1682 		 * node, the proper response is UNKNOWN */
1683 		return master;
1684 	}
1685 
1686 	hash = dlm_lockid_hash(req->name, req->namelen);
1687 
1688 	spin_lock(&dlm->spinlock);
1689 	res = __dlm_lookup_lockres(dlm, req->name, req->namelen, hash);
1690 	if (res) {
1691 		spin_lock(&res->spinlock);
1692 		master = res->owner;
1693 		if (master == dlm->node_num) {
1694 			int ret = dlm_dispatch_assert_master(dlm, res,
1695 							     0, 0, flags);
1696 			if (ret < 0) {
1697 				mlog_errno(-ENOMEM);
1698 				/* retry!? */
1699 				BUG();
1700 			}
1701 		} else /* put.. incase we are not the master */
1702 			dlm_lockres_put(res);
1703 		spin_unlock(&res->spinlock);
1704 	}
1705 	spin_unlock(&dlm->spinlock);
1706 
1707 	dlm_put(dlm);
1708 	return master;
1709 }
1710 
1711 static inline struct list_head *
1712 dlm_list_num_to_pointer(struct dlm_lock_resource *res, int list_num)
1713 {
1714 	struct list_head *ret;
1715 	BUG_ON(list_num < 0);
1716 	BUG_ON(list_num > 2);
1717 	ret = &(res->granted);
1718 	ret += list_num;
1719 	return ret;
1720 }
1721 /* TODO: do ast flush business
1722  * TODO: do MIGRATING and RECOVERING spinning
1723  */
1724 
1725 /*
1726 * NOTE about in-flight requests during migration:
1727 *
1728 * Before attempting the migrate, the master has marked the lockres as
1729 * MIGRATING and then flushed all of its pending ASTS.  So any in-flight
1730 * requests either got queued before the MIGRATING flag got set, in which
1731 * case the lock data will reflect the change and a return message is on
1732 * the way, or the request failed to get in before MIGRATING got set.  In
1733 * this case, the caller will be told to spin and wait for the MIGRATING
1734 * flag to be dropped, then recheck the master.
1735 * This holds true for the convert, cancel and unlock cases, and since lvb
1736 * updates are tied to these same messages, it applies to lvb updates as
1737 * well.  For the lock case, there is no way a lock can be on the master
1738 * queue and not be on the secondary queue since the lock is always added
1739 * locally first.  This means that the new target node will never be sent
1740 * a lock that he doesn't already have on the list.
1741 * In total, this means that the local lock is correct and should not be
1742 * updated to match the one sent by the master.  Any messages sent back
1743 * from the master before the MIGRATING flag will bring the lock properly
1744 * up-to-date, and the change will be ordered properly for the waiter.
1745 * We will *not* attempt to modify the lock underneath the waiter.
1746 */
1747 
1748 static int dlm_process_recovery_data(struct dlm_ctxt *dlm,
1749 				     struct dlm_lock_resource *res,
1750 				     struct dlm_migratable_lockres *mres)
1751 {
1752 	struct dlm_migratable_lock *ml;
1753 	struct list_head *queue;
1754 	struct list_head *tmpq = NULL;
1755 	struct dlm_lock *newlock = NULL;
1756 	struct dlm_lockstatus *lksb = NULL;
1757 	int ret = 0;
1758 	int i, j, bad;
1759 	struct dlm_lock *lock = NULL;
1760 	u8 from = O2NM_MAX_NODES;
1761 	unsigned int added = 0;
1762 	__be64 c;
1763 
1764 	mlog(0, "running %d locks for this lockres\n", mres->num_locks);
1765 	for (i=0; i<mres->num_locks; i++) {
1766 		ml = &(mres->ml[i]);
1767 
1768 		if (dlm_is_dummy_lock(dlm, ml, &from)) {
1769 			/* placeholder, just need to set the refmap bit */
1770 			BUG_ON(mres->num_locks != 1);
1771 			mlog(0, "%s:%.*s: dummy lock for %u\n",
1772 			     dlm->name, mres->lockname_len, mres->lockname,
1773 			     from);
1774 			spin_lock(&res->spinlock);
1775 			dlm_lockres_set_refmap_bit(dlm, res, from);
1776 			spin_unlock(&res->spinlock);
1777 			added++;
1778 			break;
1779 		}
1780 		BUG_ON(ml->highest_blocked != LKM_IVMODE);
1781 		newlock = NULL;
1782 		lksb = NULL;
1783 
1784 		queue = dlm_list_num_to_pointer(res, ml->list);
1785 		tmpq = NULL;
1786 
1787 		/* if the lock is for the local node it needs to
1788 		 * be moved to the proper location within the queue.
1789 		 * do not allocate a new lock structure. */
1790 		if (ml->node == dlm->node_num) {
1791 			/* MIGRATION ONLY! */
1792 			BUG_ON(!(mres->flags & DLM_MRES_MIGRATION));
1793 
1794 			spin_lock(&res->spinlock);
1795 			for (j = DLM_GRANTED_LIST; j <= DLM_BLOCKED_LIST; j++) {
1796 				tmpq = dlm_list_idx_to_ptr(res, j);
1797 				list_for_each_entry(lock, tmpq, list) {
1798 					if (lock->ml.cookie != ml->cookie)
1799 						lock = NULL;
1800 					else
1801 						break;
1802 				}
1803 				if (lock)
1804 					break;
1805 			}
1806 
1807 			/* lock is always created locally first, and
1808 			 * destroyed locally last.  it must be on the list */
1809 			if (!lock) {
1810 				c = ml->cookie;
1811 				mlog(ML_ERROR, "Could not find local lock "
1812 					       "with cookie %u:%llu, node %u, "
1813 					       "list %u, flags 0x%x, type %d, "
1814 					       "conv %d, highest blocked %d\n",
1815 				     dlm_get_lock_cookie_node(be64_to_cpu(c)),
1816 				     dlm_get_lock_cookie_seq(be64_to_cpu(c)),
1817 				     ml->node, ml->list, ml->flags, ml->type,
1818 				     ml->convert_type, ml->highest_blocked);
1819 				__dlm_print_one_lock_resource(res);
1820 				BUG();
1821 			}
1822 
1823 			if (lock->ml.node != ml->node) {
1824 				c = lock->ml.cookie;
1825 				mlog(ML_ERROR, "Mismatched node# in lock "
1826 				     "cookie %u:%llu, name %.*s, node %u\n",
1827 				     dlm_get_lock_cookie_node(be64_to_cpu(c)),
1828 				     dlm_get_lock_cookie_seq(be64_to_cpu(c)),
1829 				     res->lockname.len, res->lockname.name,
1830 				     lock->ml.node);
1831 				c = ml->cookie;
1832 				mlog(ML_ERROR, "Migrate lock cookie %u:%llu, "
1833 				     "node %u, list %u, flags 0x%x, type %d, "
1834 				     "conv %d, highest blocked %d\n",
1835 				     dlm_get_lock_cookie_node(be64_to_cpu(c)),
1836 				     dlm_get_lock_cookie_seq(be64_to_cpu(c)),
1837 				     ml->node, ml->list, ml->flags, ml->type,
1838 				     ml->convert_type, ml->highest_blocked);
1839 				__dlm_print_one_lock_resource(res);
1840 				BUG();
1841 			}
1842 
1843 			if (tmpq != queue) {
1844 				c = ml->cookie;
1845 				mlog(0, "Lock cookie %u:%llu was on list %u "
1846 				     "instead of list %u for %.*s\n",
1847 				     dlm_get_lock_cookie_node(be64_to_cpu(c)),
1848 				     dlm_get_lock_cookie_seq(be64_to_cpu(c)),
1849 				     j, ml->list, res->lockname.len,
1850 				     res->lockname.name);
1851 				__dlm_print_one_lock_resource(res);
1852 				spin_unlock(&res->spinlock);
1853 				continue;
1854 			}
1855 
1856 			/* see NOTE above about why we do not update
1857 			 * to match the master here */
1858 
1859 			/* move the lock to its proper place */
1860 			/* do not alter lock refcount.  switching lists. */
1861 			list_move_tail(&lock->list, queue);
1862 			spin_unlock(&res->spinlock);
1863 			added++;
1864 
1865 			mlog(0, "just reordered a local lock!\n");
1866 			continue;
1867 		}
1868 
1869 		/* lock is for another node. */
1870 		newlock = dlm_new_lock(ml->type, ml->node,
1871 				       be64_to_cpu(ml->cookie), NULL);
1872 		if (!newlock) {
1873 			ret = -ENOMEM;
1874 			goto leave;
1875 		}
1876 		lksb = newlock->lksb;
1877 		dlm_lock_attach_lockres(newlock, res);
1878 
1879 		if (ml->convert_type != LKM_IVMODE) {
1880 			BUG_ON(queue != &res->converting);
1881 			newlock->ml.convert_type = ml->convert_type;
1882 		}
1883 		lksb->flags |= (ml->flags &
1884 				(DLM_LKSB_PUT_LVB|DLM_LKSB_GET_LVB));
1885 
1886 		if (ml->type == LKM_NLMODE)
1887 			goto skip_lvb;
1888 
1889 		if (!dlm_lvb_is_empty(mres->lvb)) {
1890 			if (lksb->flags & DLM_LKSB_PUT_LVB) {
1891 				/* other node was trying to update
1892 				 * lvb when node died.  recreate the
1893 				 * lksb with the updated lvb. */
1894 				memcpy(lksb->lvb, mres->lvb, DLM_LVB_LEN);
1895 				/* the lock resource lvb update must happen
1896 				 * NOW, before the spinlock is dropped.
1897 				 * we no longer wait for the AST to update
1898 				 * the lvb. */
1899 				memcpy(res->lvb, mres->lvb, DLM_LVB_LEN);
1900 			} else {
1901 				/* otherwise, the node is sending its
1902 				 * most recent valid lvb info */
1903 				BUG_ON(ml->type != LKM_EXMODE &&
1904 				       ml->type != LKM_PRMODE);
1905 				if (!dlm_lvb_is_empty(res->lvb) &&
1906  				    (ml->type == LKM_EXMODE ||
1907  				     memcmp(res->lvb, mres->lvb, DLM_LVB_LEN))) {
1908  					int i;
1909  					mlog(ML_ERROR, "%s:%.*s: received bad "
1910  					     "lvb! type=%d\n", dlm->name,
1911  					     res->lockname.len,
1912  					     res->lockname.name, ml->type);
1913  					printk("lockres lvb=[");
1914  					for (i=0; i<DLM_LVB_LEN; i++)
1915  						printk("%02x", res->lvb[i]);
1916  					printk("]\nmigrated lvb=[");
1917  					for (i=0; i<DLM_LVB_LEN; i++)
1918  						printk("%02x", mres->lvb[i]);
1919  					printk("]\n");
1920  					dlm_print_one_lock_resource(res);
1921  					BUG();
1922 				}
1923 				memcpy(res->lvb, mres->lvb, DLM_LVB_LEN);
1924 			}
1925 		}
1926 skip_lvb:
1927 
1928 		/* NOTE:
1929 		 * wrt lock queue ordering and recovery:
1930 		 *    1. order of locks on granted queue is
1931 		 *       meaningless.
1932 		 *    2. order of locks on converting queue is
1933 		 *       LOST with the node death.  sorry charlie.
1934 		 *    3. order of locks on the blocked queue is
1935 		 *       also LOST.
1936 		 * order of locks does not affect integrity, it
1937 		 * just means that a lock request may get pushed
1938 		 * back in line as a result of the node death.
1939 		 * also note that for a given node the lock order
1940 		 * for its secondary queue locks is preserved
1941 		 * relative to each other, but clearly *not*
1942 		 * preserved relative to locks from other nodes.
1943 		 */
1944 		bad = 0;
1945 		spin_lock(&res->spinlock);
1946 		list_for_each_entry(lock, queue, list) {
1947 			if (lock->ml.cookie == ml->cookie) {
1948 				c = lock->ml.cookie;
1949 				mlog(ML_ERROR, "%s:%.*s: %u:%llu: lock already "
1950 				     "exists on this lockres!\n", dlm->name,
1951 				     res->lockname.len, res->lockname.name,
1952 				     dlm_get_lock_cookie_node(be64_to_cpu(c)),
1953 				     dlm_get_lock_cookie_seq(be64_to_cpu(c)));
1954 
1955 				mlog(ML_NOTICE, "sent lock: type=%d, conv=%d, "
1956 				     "node=%u, cookie=%u:%llu, queue=%d\n",
1957 	      			     ml->type, ml->convert_type, ml->node,
1958 				     dlm_get_lock_cookie_node(be64_to_cpu(ml->cookie)),
1959 				     dlm_get_lock_cookie_seq(be64_to_cpu(ml->cookie)),
1960 				     ml->list);
1961 
1962 				__dlm_print_one_lock_resource(res);
1963 				bad = 1;
1964 				break;
1965 			}
1966 		}
1967 		if (!bad) {
1968 			dlm_lock_get(newlock);
1969 			list_add_tail(&newlock->list, queue);
1970 			mlog(0, "%s:%.*s: added lock for node %u, "
1971 			     "setting refmap bit\n", dlm->name,
1972 			     res->lockname.len, res->lockname.name, ml->node);
1973 			dlm_lockres_set_refmap_bit(dlm, res, ml->node);
1974 			added++;
1975 		}
1976 		spin_unlock(&res->spinlock);
1977 	}
1978 	mlog(0, "done running all the locks\n");
1979 
1980 leave:
1981 	/* balance the ref taken when the work was queued */
1982 	spin_lock(&res->spinlock);
1983 	dlm_lockres_drop_inflight_ref(dlm, res);
1984 	spin_unlock(&res->spinlock);
1985 
1986 	if (ret < 0) {
1987 		mlog_errno(ret);
1988 		if (newlock)
1989 			dlm_lock_put(newlock);
1990 	}
1991 
1992 	return ret;
1993 }
1994 
1995 void dlm_move_lockres_to_recovery_list(struct dlm_ctxt *dlm,
1996 				       struct dlm_lock_resource *res)
1997 {
1998 	int i;
1999 	struct list_head *queue;
2000 	struct dlm_lock *lock, *next;
2001 
2002 	assert_spin_locked(&dlm->spinlock);
2003 	assert_spin_locked(&res->spinlock);
2004 	res->state |= DLM_LOCK_RES_RECOVERING;
2005 	if (!list_empty(&res->recovering)) {
2006 		mlog(0,
2007 		     "Recovering res %s:%.*s, is already on recovery list!\n",
2008 		     dlm->name, res->lockname.len, res->lockname.name);
2009 		list_del_init(&res->recovering);
2010 		dlm_lockres_put(res);
2011 	}
2012 	/* We need to hold a reference while on the recovery list */
2013 	dlm_lockres_get(res);
2014 	list_add_tail(&res->recovering, &dlm->reco.resources);
2015 
2016 	/* find any pending locks and put them back on proper list */
2017 	for (i=DLM_BLOCKED_LIST; i>=DLM_GRANTED_LIST; i--) {
2018 		queue = dlm_list_idx_to_ptr(res, i);
2019 		list_for_each_entry_safe(lock, next, queue, list) {
2020 			dlm_lock_get(lock);
2021 			if (lock->convert_pending) {
2022 				/* move converting lock back to granted */
2023 				BUG_ON(i != DLM_CONVERTING_LIST);
2024 				mlog(0, "node died with convert pending "
2025 				     "on %.*s. move back to granted list.\n",
2026 				     res->lockname.len, res->lockname.name);
2027 				dlm_revert_pending_convert(res, lock);
2028 				lock->convert_pending = 0;
2029 			} else if (lock->lock_pending) {
2030 				/* remove pending lock requests completely */
2031 				BUG_ON(i != DLM_BLOCKED_LIST);
2032 				mlog(0, "node died with lock pending "
2033 				     "on %.*s. remove from blocked list and skip.\n",
2034 				     res->lockname.len, res->lockname.name);
2035 				/* lock will be floating until ref in
2036 				 * dlmlock_remote is freed after the network
2037 				 * call returns.  ok for it to not be on any
2038 				 * list since no ast can be called
2039 				 * (the master is dead). */
2040 				dlm_revert_pending_lock(res, lock);
2041 				lock->lock_pending = 0;
2042 			} else if (lock->unlock_pending) {
2043 				/* if an unlock was in progress, treat as
2044 				 * if this had completed successfully
2045 				 * before sending this lock state to the
2046 				 * new master.  note that the dlm_unlock
2047 				 * call is still responsible for calling
2048 				 * the unlockast.  that will happen after
2049 				 * the network call times out.  for now,
2050 				 * just move lists to prepare the new
2051 				 * recovery master.  */
2052 				BUG_ON(i != DLM_GRANTED_LIST);
2053 				mlog(0, "node died with unlock pending "
2054 				     "on %.*s. remove from blocked list and skip.\n",
2055 				     res->lockname.len, res->lockname.name);
2056 				dlm_commit_pending_unlock(res, lock);
2057 				lock->unlock_pending = 0;
2058 			} else if (lock->cancel_pending) {
2059 				/* if a cancel was in progress, treat as
2060 				 * if this had completed successfully
2061 				 * before sending this lock state to the
2062 				 * new master */
2063 				BUG_ON(i != DLM_CONVERTING_LIST);
2064 				mlog(0, "node died with cancel pending "
2065 				     "on %.*s. move back to granted list.\n",
2066 				     res->lockname.len, res->lockname.name);
2067 				dlm_commit_pending_cancel(res, lock);
2068 				lock->cancel_pending = 0;
2069 			}
2070 			dlm_lock_put(lock);
2071 		}
2072 	}
2073 }
2074 
2075 
2076 
2077 /* removes all recovered locks from the recovery list.
2078  * sets the res->owner to the new master.
2079  * unsets the RECOVERY flag and wakes waiters. */
2080 static void dlm_finish_local_lockres_recovery(struct dlm_ctxt *dlm,
2081 					      u8 dead_node, u8 new_master)
2082 {
2083 	int i;
2084 	struct hlist_head *bucket;
2085 	struct dlm_lock_resource *res, *next;
2086 
2087 	assert_spin_locked(&dlm->spinlock);
2088 
2089 	list_for_each_entry_safe(res, next, &dlm->reco.resources, recovering) {
2090 		if (res->owner == dead_node) {
2091 			mlog(0, "%s: res %.*s, Changing owner from %u to %u\n",
2092 			     dlm->name, res->lockname.len, res->lockname.name,
2093 			     res->owner, new_master);
2094 			list_del_init(&res->recovering);
2095 			spin_lock(&res->spinlock);
2096 			/* new_master has our reference from
2097 			 * the lock state sent during recovery */
2098 			dlm_change_lockres_owner(dlm, res, new_master);
2099 			res->state &= ~DLM_LOCK_RES_RECOVERING;
2100 			if (__dlm_lockres_has_locks(res))
2101 				__dlm_dirty_lockres(dlm, res);
2102 			spin_unlock(&res->spinlock);
2103 			wake_up(&res->wq);
2104 			dlm_lockres_put(res);
2105 		}
2106 	}
2107 
2108 	/* this will become unnecessary eventually, but
2109 	 * for now we need to run the whole hash, clear
2110 	 * the RECOVERING state and set the owner
2111 	 * if necessary */
2112 	for (i = 0; i < DLM_HASH_BUCKETS; i++) {
2113 		bucket = dlm_lockres_hash(dlm, i);
2114 		hlist_for_each_entry(res, bucket, hash_node) {
2115 			if (!(res->state & DLM_LOCK_RES_RECOVERING))
2116 				continue;
2117 
2118 			if (res->owner != dead_node &&
2119 			    res->owner != dlm->node_num)
2120 				continue;
2121 
2122 			if (!list_empty(&res->recovering)) {
2123 				list_del_init(&res->recovering);
2124 				dlm_lockres_put(res);
2125 			}
2126 
2127 			/* new_master has our reference from
2128 			 * the lock state sent during recovery */
2129 			mlog(0, "%s: res %.*s, Changing owner from %u to %u\n",
2130 			     dlm->name, res->lockname.len, res->lockname.name,
2131 			     res->owner, new_master);
2132 			spin_lock(&res->spinlock);
2133 			dlm_change_lockres_owner(dlm, res, new_master);
2134 			res->state &= ~DLM_LOCK_RES_RECOVERING;
2135 			if (__dlm_lockres_has_locks(res))
2136 				__dlm_dirty_lockres(dlm, res);
2137 			spin_unlock(&res->spinlock);
2138 			wake_up(&res->wq);
2139 		}
2140 	}
2141 }
2142 
2143 static inline int dlm_lvb_needs_invalidation(struct dlm_lock *lock, int local)
2144 {
2145 	if (local) {
2146 		if (lock->ml.type != LKM_EXMODE &&
2147 		    lock->ml.type != LKM_PRMODE)
2148 			return 1;
2149 	} else if (lock->ml.type == LKM_EXMODE)
2150 		return 1;
2151 	return 0;
2152 }
2153 
2154 static void dlm_revalidate_lvb(struct dlm_ctxt *dlm,
2155 			       struct dlm_lock_resource *res, u8 dead_node)
2156 {
2157 	struct list_head *queue;
2158 	struct dlm_lock *lock;
2159 	int blank_lvb = 0, local = 0;
2160 	int i;
2161 	u8 search_node;
2162 
2163 	assert_spin_locked(&dlm->spinlock);
2164 	assert_spin_locked(&res->spinlock);
2165 
2166 	if (res->owner == dlm->node_num)
2167 		/* if this node owned the lockres, and if the dead node
2168 		 * had an EX when he died, blank out the lvb */
2169 		search_node = dead_node;
2170 	else {
2171 		/* if this is a secondary lockres, and we had no EX or PR
2172 		 * locks granted, we can no longer trust the lvb */
2173 		search_node = dlm->node_num;
2174 		local = 1;  /* check local state for valid lvb */
2175 	}
2176 
2177 	for (i=DLM_GRANTED_LIST; i<=DLM_CONVERTING_LIST; i++) {
2178 		queue = dlm_list_idx_to_ptr(res, i);
2179 		list_for_each_entry(lock, queue, list) {
2180 			if (lock->ml.node == search_node) {
2181 				if (dlm_lvb_needs_invalidation(lock, local)) {
2182 					/* zero the lksb lvb and lockres lvb */
2183 					blank_lvb = 1;
2184 					memset(lock->lksb->lvb, 0, DLM_LVB_LEN);
2185 				}
2186 			}
2187 		}
2188 	}
2189 
2190 	if (blank_lvb) {
2191 		mlog(0, "clearing %.*s lvb, dead node %u had EX\n",
2192 		     res->lockname.len, res->lockname.name, dead_node);
2193 		memset(res->lvb, 0, DLM_LVB_LEN);
2194 	}
2195 }
2196 
2197 static void dlm_free_dead_locks(struct dlm_ctxt *dlm,
2198 				struct dlm_lock_resource *res, u8 dead_node)
2199 {
2200 	struct dlm_lock *lock, *next;
2201 	unsigned int freed = 0;
2202 
2203 	/* this node is the lockres master:
2204 	 * 1) remove any stale locks for the dead node
2205 	 * 2) if the dead node had an EX when he died, blank out the lvb
2206 	 */
2207 	assert_spin_locked(&dlm->spinlock);
2208 	assert_spin_locked(&res->spinlock);
2209 
2210 	/* We do two dlm_lock_put(). One for removing from list and the other is
2211 	 * to force the DLM_UNLOCK_FREE_LOCK action so as to free the locks */
2212 
2213 	/* TODO: check pending_asts, pending_basts here */
2214 	list_for_each_entry_safe(lock, next, &res->granted, list) {
2215 		if (lock->ml.node == dead_node) {
2216 			list_del_init(&lock->list);
2217 			dlm_lock_put(lock);
2218 			/* Can't schedule DLM_UNLOCK_FREE_LOCK - do manually */
2219 			dlm_lock_put(lock);
2220 			freed++;
2221 		}
2222 	}
2223 	list_for_each_entry_safe(lock, next, &res->converting, list) {
2224 		if (lock->ml.node == dead_node) {
2225 			list_del_init(&lock->list);
2226 			dlm_lock_put(lock);
2227 			/* Can't schedule DLM_UNLOCK_FREE_LOCK - do manually */
2228 			dlm_lock_put(lock);
2229 			freed++;
2230 		}
2231 	}
2232 	list_for_each_entry_safe(lock, next, &res->blocked, list) {
2233 		if (lock->ml.node == dead_node) {
2234 			list_del_init(&lock->list);
2235 			dlm_lock_put(lock);
2236 			/* Can't schedule DLM_UNLOCK_FREE_LOCK - do manually */
2237 			dlm_lock_put(lock);
2238 			freed++;
2239 		}
2240 	}
2241 
2242 	if (freed) {
2243 		mlog(0, "%s:%.*s: freed %u locks for dead node %u, "
2244 		     "dropping ref from lockres\n", dlm->name,
2245 		     res->lockname.len, res->lockname.name, freed, dead_node);
2246 		if(!test_bit(dead_node, res->refmap)) {
2247 			mlog(ML_ERROR, "%s:%.*s: freed %u locks for dead node %u, "
2248 			     "but ref was not set\n", dlm->name,
2249 			     res->lockname.len, res->lockname.name, freed, dead_node);
2250 			__dlm_print_one_lock_resource(res);
2251 		}
2252 		dlm_lockres_clear_refmap_bit(dlm, res, dead_node);
2253 	} else if (test_bit(dead_node, res->refmap)) {
2254 		mlog(0, "%s:%.*s: dead node %u had a ref, but had "
2255 		     "no locks and had not purged before dying\n", dlm->name,
2256 		     res->lockname.len, res->lockname.name, dead_node);
2257 		dlm_lockres_clear_refmap_bit(dlm, res, dead_node);
2258 	}
2259 
2260 	/* do not kick thread yet */
2261 	__dlm_dirty_lockres(dlm, res);
2262 }
2263 
2264 /* if this node is the recovery master, and there are no
2265  * locks for a given lockres owned by this node that are in
2266  * either PR or EX mode, zero out the lvb before requesting.
2267  *
2268  */
2269 
2270 
2271 static void dlm_do_local_recovery_cleanup(struct dlm_ctxt *dlm, u8 dead_node)
2272 {
2273 	struct dlm_lock_resource *res;
2274 	int i;
2275 	struct hlist_head *bucket;
2276 	struct dlm_lock *lock;
2277 
2278 
2279 	/* purge any stale mles */
2280 	dlm_clean_master_list(dlm, dead_node);
2281 
2282 	/*
2283 	 * now clean up all lock resources.  there are two rules:
2284 	 *
2285 	 * 1) if the dead node was the master, move the lockres
2286 	 *    to the recovering list.  set the RECOVERING flag.
2287 	 *    this lockres needs to be cleaned up before it can
2288 	 *    be used further.
2289 	 *
2290 	 * 2) if this node was the master, remove all locks from
2291 	 *    each of the lockres queues that were owned by the
2292 	 *    dead node.  once recovery finishes, the dlm thread
2293 	 *    can be kicked again to see if any ASTs or BASTs
2294 	 *    need to be fired as a result.
2295 	 */
2296 	for (i = 0; i < DLM_HASH_BUCKETS; i++) {
2297 		bucket = dlm_lockres_hash(dlm, i);
2298 		hlist_for_each_entry(res, bucket, hash_node) {
2299  			/* always prune any $RECOVERY entries for dead nodes,
2300  			 * otherwise hangs can occur during later recovery */
2301 			if (dlm_is_recovery_lock(res->lockname.name,
2302 						 res->lockname.len)) {
2303 				spin_lock(&res->spinlock);
2304 				list_for_each_entry(lock, &res->granted, list) {
2305 					if (lock->ml.node == dead_node) {
2306 						mlog(0, "AHA! there was "
2307 						     "a $RECOVERY lock for dead "
2308 						     "node %u (%s)!\n",
2309 						     dead_node, dlm->name);
2310 						list_del_init(&lock->list);
2311 						dlm_lock_put(lock);
2312 						break;
2313 					}
2314 				}
2315 				spin_unlock(&res->spinlock);
2316 				continue;
2317 			}
2318 			spin_lock(&res->spinlock);
2319 			/* zero the lvb if necessary */
2320 			dlm_revalidate_lvb(dlm, res, dead_node);
2321 			if (res->owner == dead_node) {
2322 				if (res->state & DLM_LOCK_RES_DROPPING_REF) {
2323 					mlog(ML_NOTICE, "%s: res %.*s, Skip "
2324 					     "recovery as it is being freed\n",
2325 					     dlm->name, res->lockname.len,
2326 					     res->lockname.name);
2327 				} else
2328 					dlm_move_lockres_to_recovery_list(dlm,
2329 									  res);
2330 
2331 			} else if (res->owner == dlm->node_num) {
2332 				dlm_free_dead_locks(dlm, res, dead_node);
2333 				__dlm_lockres_calc_usage(dlm, res);
2334 			}
2335 			spin_unlock(&res->spinlock);
2336 		}
2337 	}
2338 
2339 }
2340 
2341 static void __dlm_hb_node_down(struct dlm_ctxt *dlm, int idx)
2342 {
2343 	assert_spin_locked(&dlm->spinlock);
2344 
2345 	if (dlm->reco.new_master == idx) {
2346 		mlog(0, "%s: recovery master %d just died\n",
2347 		     dlm->name, idx);
2348 		if (dlm->reco.state & DLM_RECO_STATE_FINALIZE) {
2349 			/* finalize1 was reached, so it is safe to clear
2350 			 * the new_master and dead_node.  that recovery
2351 			 * is complete. */
2352 			mlog(0, "%s: dead master %d had reached "
2353 			     "finalize1 state, clearing\n", dlm->name, idx);
2354 			dlm->reco.state &= ~DLM_RECO_STATE_FINALIZE;
2355 			__dlm_reset_recovery(dlm);
2356 		}
2357 	}
2358 
2359 	/* Clean up join state on node death. */
2360 	if (dlm->joining_node == idx) {
2361 		mlog(0, "Clearing join state for node %u\n", idx);
2362 		__dlm_set_joining_node(dlm, DLM_LOCK_RES_OWNER_UNKNOWN);
2363 	}
2364 
2365 	/* check to see if the node is already considered dead */
2366 	if (!test_bit(idx, dlm->live_nodes_map)) {
2367 		mlog(0, "for domain %s, node %d is already dead. "
2368 		     "another node likely did recovery already.\n",
2369 		     dlm->name, idx);
2370 		return;
2371 	}
2372 
2373 	/* check to see if we do not care about this node */
2374 	if (!test_bit(idx, dlm->domain_map)) {
2375 		/* This also catches the case that we get a node down
2376 		 * but haven't joined the domain yet. */
2377 		mlog(0, "node %u already removed from domain!\n", idx);
2378 		return;
2379 	}
2380 
2381 	clear_bit(idx, dlm->live_nodes_map);
2382 
2383 	/* make sure local cleanup occurs before the heartbeat events */
2384 	if (!test_bit(idx, dlm->recovery_map))
2385 		dlm_do_local_recovery_cleanup(dlm, idx);
2386 
2387 	/* notify anything attached to the heartbeat events */
2388 	dlm_hb_event_notify_attached(dlm, idx, 0);
2389 
2390 	mlog(0, "node %u being removed from domain map!\n", idx);
2391 	clear_bit(idx, dlm->domain_map);
2392 	clear_bit(idx, dlm->exit_domain_map);
2393 	/* wake up migration waiters if a node goes down.
2394 	 * perhaps later we can genericize this for other waiters. */
2395 	wake_up(&dlm->migration_wq);
2396 
2397 	if (test_bit(idx, dlm->recovery_map))
2398 		mlog(0, "domain %s, node %u already added "
2399 		     "to recovery map!\n", dlm->name, idx);
2400 	else
2401 		set_bit(idx, dlm->recovery_map);
2402 }
2403 
2404 void dlm_hb_node_down_cb(struct o2nm_node *node, int idx, void *data)
2405 {
2406 	struct dlm_ctxt *dlm = data;
2407 
2408 	if (!dlm_grab(dlm))
2409 		return;
2410 
2411 	/*
2412 	 * This will notify any dlm users that a node in our domain
2413 	 * went away without notifying us first.
2414 	 */
2415 	if (test_bit(idx, dlm->domain_map))
2416 		dlm_fire_domain_eviction_callbacks(dlm, idx);
2417 
2418 	spin_lock(&dlm->spinlock);
2419 	__dlm_hb_node_down(dlm, idx);
2420 	spin_unlock(&dlm->spinlock);
2421 
2422 	dlm_put(dlm);
2423 }
2424 
2425 void dlm_hb_node_up_cb(struct o2nm_node *node, int idx, void *data)
2426 {
2427 	struct dlm_ctxt *dlm = data;
2428 
2429 	if (!dlm_grab(dlm))
2430 		return;
2431 
2432 	spin_lock(&dlm->spinlock);
2433 	set_bit(idx, dlm->live_nodes_map);
2434 	/* do NOT notify mle attached to the heartbeat events.
2435 	 * new nodes are not interesting in mastery until joined. */
2436 	spin_unlock(&dlm->spinlock);
2437 
2438 	dlm_put(dlm);
2439 }
2440 
2441 static void dlm_reco_ast(void *astdata)
2442 {
2443 	struct dlm_ctxt *dlm = astdata;
2444 	mlog(0, "ast for recovery lock fired!, this=%u, dlm=%s\n",
2445 	     dlm->node_num, dlm->name);
2446 }
2447 static void dlm_reco_bast(void *astdata, int blocked_type)
2448 {
2449 	struct dlm_ctxt *dlm = astdata;
2450 	mlog(0, "bast for recovery lock fired!, this=%u, dlm=%s\n",
2451 	     dlm->node_num, dlm->name);
2452 }
2453 static void dlm_reco_unlock_ast(void *astdata, enum dlm_status st)
2454 {
2455 	mlog(0, "unlockast for recovery lock fired!\n");
2456 }
2457 
2458 /*
2459  * dlm_pick_recovery_master will continually attempt to use
2460  * dlmlock() on the special "$RECOVERY" lockres with the
2461  * LKM_NOQUEUE flag to get an EX.  every thread that enters
2462  * this function on each node racing to become the recovery
2463  * master will not stop attempting this until either:
2464  * a) this node gets the EX (and becomes the recovery master),
2465  * or b) dlm->reco.new_master gets set to some nodenum
2466  * != O2NM_INVALID_NODE_NUM (another node will do the reco).
2467  * so each time a recovery master is needed, the entire cluster
2468  * will sync at this point.  if the new master dies, that will
2469  * be detected in dlm_do_recovery */
2470 static int dlm_pick_recovery_master(struct dlm_ctxt *dlm)
2471 {
2472 	enum dlm_status ret;
2473 	struct dlm_lockstatus lksb;
2474 	int status = -EINVAL;
2475 
2476 	mlog(0, "starting recovery of %s at %lu, dead=%u, this=%u\n",
2477 	     dlm->name, jiffies, dlm->reco.dead_node, dlm->node_num);
2478 again:
2479 	memset(&lksb, 0, sizeof(lksb));
2480 
2481 	ret = dlmlock(dlm, LKM_EXMODE, &lksb, LKM_NOQUEUE|LKM_RECOVERY,
2482 		      DLM_RECOVERY_LOCK_NAME, DLM_RECOVERY_LOCK_NAME_LEN,
2483 		      dlm_reco_ast, dlm, dlm_reco_bast);
2484 
2485 	mlog(0, "%s: dlmlock($RECOVERY) returned %d, lksb=%d\n",
2486 	     dlm->name, ret, lksb.status);
2487 
2488 	if (ret == DLM_NORMAL) {
2489 		mlog(0, "dlm=%s dlmlock says I got it (this=%u)\n",
2490 		     dlm->name, dlm->node_num);
2491 
2492 		/* got the EX lock.  check to see if another node
2493 		 * just became the reco master */
2494 		if (dlm_reco_master_ready(dlm)) {
2495 			mlog(0, "%s: got reco EX lock, but %u will "
2496 			     "do the recovery\n", dlm->name,
2497 			     dlm->reco.new_master);
2498 			status = -EEXIST;
2499 		} else {
2500 			status = 0;
2501 
2502 			/* see if recovery was already finished elsewhere */
2503 			spin_lock(&dlm->spinlock);
2504 			if (dlm->reco.dead_node == O2NM_INVALID_NODE_NUM) {
2505 				status = -EINVAL;
2506 				mlog(0, "%s: got reco EX lock, but "
2507 				     "node got recovered already\n", dlm->name);
2508 				if (dlm->reco.new_master != O2NM_INVALID_NODE_NUM) {
2509 					mlog(ML_ERROR, "%s: new master is %u "
2510 					     "but no dead node!\n",
2511 					     dlm->name, dlm->reco.new_master);
2512 					BUG();
2513 				}
2514 			}
2515 			spin_unlock(&dlm->spinlock);
2516 		}
2517 
2518 		/* if this node has actually become the recovery master,
2519 		 * set the master and send the messages to begin recovery */
2520 		if (!status) {
2521 			mlog(0, "%s: dead=%u, this=%u, sending "
2522 			     "begin_reco now\n", dlm->name,
2523 			     dlm->reco.dead_node, dlm->node_num);
2524 			status = dlm_send_begin_reco_message(dlm,
2525 				      dlm->reco.dead_node);
2526 			/* this always succeeds */
2527 			BUG_ON(status);
2528 
2529 			/* set the new_master to this node */
2530 			spin_lock(&dlm->spinlock);
2531 			dlm_set_reco_master(dlm, dlm->node_num);
2532 			spin_unlock(&dlm->spinlock);
2533 		}
2534 
2535 		/* recovery lock is a special case.  ast will not get fired,
2536 		 * so just go ahead and unlock it. */
2537 		ret = dlmunlock(dlm, &lksb, 0, dlm_reco_unlock_ast, dlm);
2538 		if (ret == DLM_DENIED) {
2539 			mlog(0, "got DLM_DENIED, trying LKM_CANCEL\n");
2540 			ret = dlmunlock(dlm, &lksb, LKM_CANCEL, dlm_reco_unlock_ast, dlm);
2541 		}
2542 		if (ret != DLM_NORMAL) {
2543 			/* this would really suck. this could only happen
2544 			 * if there was a network error during the unlock
2545 			 * because of node death.  this means the unlock
2546 			 * is actually "done" and the lock structure is
2547 			 * even freed.  we can continue, but only
2548 			 * because this specific lock name is special. */
2549 			mlog(ML_ERROR, "dlmunlock returned %d\n", ret);
2550 		}
2551 	} else if (ret == DLM_NOTQUEUED) {
2552 		mlog(0, "dlm=%s dlmlock says another node got it (this=%u)\n",
2553 		     dlm->name, dlm->node_num);
2554 		/* another node is master. wait on
2555 		 * reco.new_master != O2NM_INVALID_NODE_NUM
2556 		 * for at most one second */
2557 		wait_event_timeout(dlm->dlm_reco_thread_wq,
2558 					 dlm_reco_master_ready(dlm),
2559 					 msecs_to_jiffies(1000));
2560 		if (!dlm_reco_master_ready(dlm)) {
2561 			mlog(0, "%s: reco master taking awhile\n",
2562 			     dlm->name);
2563 			goto again;
2564 		}
2565 		/* another node has informed this one that it is reco master */
2566 		mlog(0, "%s: reco master %u is ready to recover %u\n",
2567 		     dlm->name, dlm->reco.new_master, dlm->reco.dead_node);
2568 		status = -EEXIST;
2569 	} else if (ret == DLM_RECOVERING) {
2570 		mlog(0, "dlm=%s dlmlock says master node died (this=%u)\n",
2571 		     dlm->name, dlm->node_num);
2572 		goto again;
2573 	} else {
2574 		struct dlm_lock_resource *res;
2575 
2576 		/* dlmlock returned something other than NOTQUEUED or NORMAL */
2577 		mlog(ML_ERROR, "%s: got %s from dlmlock($RECOVERY), "
2578 		     "lksb.status=%s\n", dlm->name, dlm_errname(ret),
2579 		     dlm_errname(lksb.status));
2580 		res = dlm_lookup_lockres(dlm, DLM_RECOVERY_LOCK_NAME,
2581 					 DLM_RECOVERY_LOCK_NAME_LEN);
2582 		if (res) {
2583 			dlm_print_one_lock_resource(res);
2584 			dlm_lockres_put(res);
2585 		} else {
2586 			mlog(ML_ERROR, "recovery lock not found\n");
2587 		}
2588 		BUG();
2589 	}
2590 
2591 	return status;
2592 }
2593 
2594 static int dlm_send_begin_reco_message(struct dlm_ctxt *dlm, u8 dead_node)
2595 {
2596 	struct dlm_begin_reco br;
2597 	int ret = 0;
2598 	struct dlm_node_iter iter;
2599 	int nodenum;
2600 	int status;
2601 
2602 	mlog(0, "%s: dead node is %u\n", dlm->name, dead_node);
2603 
2604 	spin_lock(&dlm->spinlock);
2605 	dlm_node_iter_init(dlm->domain_map, &iter);
2606 	spin_unlock(&dlm->spinlock);
2607 
2608 	clear_bit(dead_node, iter.node_map);
2609 
2610 	memset(&br, 0, sizeof(br));
2611 	br.node_idx = dlm->node_num;
2612 	br.dead_node = dead_node;
2613 
2614 	while ((nodenum = dlm_node_iter_next(&iter)) >= 0) {
2615 		ret = 0;
2616 		if (nodenum == dead_node) {
2617 			mlog(0, "not sending begin reco to dead node "
2618 				  "%u\n", dead_node);
2619 			continue;
2620 		}
2621 		if (nodenum == dlm->node_num) {
2622 			mlog(0, "not sending begin reco to self\n");
2623 			continue;
2624 		}
2625 retry:
2626 		ret = -EINVAL;
2627 		mlog(0, "attempting to send begin reco msg to %d\n",
2628 			  nodenum);
2629 		ret = o2net_send_message(DLM_BEGIN_RECO_MSG, dlm->key,
2630 					 &br, sizeof(br), nodenum, &status);
2631 		/* negative status is handled ok by caller here */
2632 		if (ret >= 0)
2633 			ret = status;
2634 		if (dlm_is_host_down(ret)) {
2635 			/* node is down.  not involved in recovery
2636 			 * so just keep going */
2637 			mlog(ML_NOTICE, "%s: node %u was down when sending "
2638 			     "begin reco msg (%d)\n", dlm->name, nodenum, ret);
2639 			ret = 0;
2640 		}
2641 
2642 		/*
2643 		 * Prior to commit aad1b15310b9bcd59fa81ab8f2b1513b59553ea8,
2644 		 * dlm_begin_reco_handler() returned EAGAIN and not -EAGAIN.
2645 		 * We are handling both for compatibility reasons.
2646 		 */
2647 		if (ret == -EAGAIN || ret == EAGAIN) {
2648 			mlog(0, "%s: trying to start recovery of node "
2649 			     "%u, but node %u is waiting for last recovery "
2650 			     "to complete, backoff for a bit\n", dlm->name,
2651 			     dead_node, nodenum);
2652 			msleep(100);
2653 			goto retry;
2654 		}
2655 		if (ret < 0) {
2656 			struct dlm_lock_resource *res;
2657 
2658 			/* this is now a serious problem, possibly ENOMEM
2659 			 * in the network stack.  must retry */
2660 			mlog_errno(ret);
2661 			mlog(ML_ERROR, "begin reco of dlm %s to node %u "
2662 			     "returned %d\n", dlm->name, nodenum, ret);
2663 			res = dlm_lookup_lockres(dlm, DLM_RECOVERY_LOCK_NAME,
2664 						 DLM_RECOVERY_LOCK_NAME_LEN);
2665 			if (res) {
2666 				dlm_print_one_lock_resource(res);
2667 				dlm_lockres_put(res);
2668 			} else {
2669 				mlog(ML_ERROR, "recovery lock not found\n");
2670 			}
2671 			/* sleep for a bit in hopes that we can avoid
2672 			 * another ENOMEM */
2673 			msleep(100);
2674 			goto retry;
2675 		}
2676 	}
2677 
2678 	return ret;
2679 }
2680 
2681 int dlm_begin_reco_handler(struct o2net_msg *msg, u32 len, void *data,
2682 			   void **ret_data)
2683 {
2684 	struct dlm_ctxt *dlm = data;
2685 	struct dlm_begin_reco *br = (struct dlm_begin_reco *)msg->buf;
2686 
2687 	/* ok to return 0, domain has gone away */
2688 	if (!dlm_grab(dlm))
2689 		return 0;
2690 
2691 	spin_lock(&dlm->spinlock);
2692 	if (dlm->reco.state & DLM_RECO_STATE_FINALIZE) {
2693 		mlog(0, "%s: node %u wants to recover node %u (%u:%u) "
2694 		     "but this node is in finalize state, waiting on finalize2\n",
2695 		     dlm->name, br->node_idx, br->dead_node,
2696 		     dlm->reco.dead_node, dlm->reco.new_master);
2697 		spin_unlock(&dlm->spinlock);
2698 		return -EAGAIN;
2699 	}
2700 	spin_unlock(&dlm->spinlock);
2701 
2702 	mlog(0, "%s: node %u wants to recover node %u (%u:%u)\n",
2703 	     dlm->name, br->node_idx, br->dead_node,
2704 	     dlm->reco.dead_node, dlm->reco.new_master);
2705 
2706 	dlm_fire_domain_eviction_callbacks(dlm, br->dead_node);
2707 
2708 	spin_lock(&dlm->spinlock);
2709 	if (dlm->reco.new_master != O2NM_INVALID_NODE_NUM) {
2710 		if (test_bit(dlm->reco.new_master, dlm->recovery_map)) {
2711 			mlog(0, "%s: new_master %u died, changing "
2712 			     "to %u\n", dlm->name, dlm->reco.new_master,
2713 			     br->node_idx);
2714 		} else {
2715 			mlog(0, "%s: new_master %u NOT DEAD, changing "
2716 			     "to %u\n", dlm->name, dlm->reco.new_master,
2717 			     br->node_idx);
2718 			/* may not have seen the new master as dead yet */
2719 		}
2720 	}
2721 	if (dlm->reco.dead_node != O2NM_INVALID_NODE_NUM) {
2722 		mlog(ML_NOTICE, "%s: dead_node previously set to %u, "
2723 		     "node %u changing it to %u\n", dlm->name,
2724 		     dlm->reco.dead_node, br->node_idx, br->dead_node);
2725 	}
2726 	dlm_set_reco_master(dlm, br->node_idx);
2727 	dlm_set_reco_dead_node(dlm, br->dead_node);
2728 	if (!test_bit(br->dead_node, dlm->recovery_map)) {
2729 		mlog(0, "recovery master %u sees %u as dead, but this "
2730 		     "node has not yet.  marking %u as dead\n",
2731 		     br->node_idx, br->dead_node, br->dead_node);
2732 		if (!test_bit(br->dead_node, dlm->domain_map) ||
2733 		    !test_bit(br->dead_node, dlm->live_nodes_map))
2734 			mlog(0, "%u not in domain/live_nodes map "
2735 			     "so setting it in reco map manually\n",
2736 			     br->dead_node);
2737 		/* force the recovery cleanup in __dlm_hb_node_down
2738 		 * both of these will be cleared in a moment */
2739 		set_bit(br->dead_node, dlm->domain_map);
2740 		set_bit(br->dead_node, dlm->live_nodes_map);
2741 		__dlm_hb_node_down(dlm, br->dead_node);
2742 	}
2743 	spin_unlock(&dlm->spinlock);
2744 
2745 	dlm_kick_recovery_thread(dlm);
2746 
2747 	mlog(0, "%s: recovery started by node %u, for %u (%u:%u)\n",
2748 	     dlm->name, br->node_idx, br->dead_node,
2749 	     dlm->reco.dead_node, dlm->reco.new_master);
2750 
2751 	dlm_put(dlm);
2752 	return 0;
2753 }
2754 
2755 #define DLM_FINALIZE_STAGE2  0x01
2756 static int dlm_send_finalize_reco_message(struct dlm_ctxt *dlm)
2757 {
2758 	int ret = 0;
2759 	struct dlm_finalize_reco fr;
2760 	struct dlm_node_iter iter;
2761 	int nodenum;
2762 	int status;
2763 	int stage = 1;
2764 
2765 	mlog(0, "finishing recovery for node %s:%u, "
2766 	     "stage %d\n", dlm->name, dlm->reco.dead_node, stage);
2767 
2768 	spin_lock(&dlm->spinlock);
2769 	dlm_node_iter_init(dlm->domain_map, &iter);
2770 	spin_unlock(&dlm->spinlock);
2771 
2772 stage2:
2773 	memset(&fr, 0, sizeof(fr));
2774 	fr.node_idx = dlm->node_num;
2775 	fr.dead_node = dlm->reco.dead_node;
2776 	if (stage == 2)
2777 		fr.flags |= DLM_FINALIZE_STAGE2;
2778 
2779 	while ((nodenum = dlm_node_iter_next(&iter)) >= 0) {
2780 		if (nodenum == dlm->node_num)
2781 			continue;
2782 		ret = o2net_send_message(DLM_FINALIZE_RECO_MSG, dlm->key,
2783 					 &fr, sizeof(fr), nodenum, &status);
2784 		if (ret >= 0)
2785 			ret = status;
2786 		if (ret < 0) {
2787 			mlog(ML_ERROR, "Error %d when sending message %u (key "
2788 			     "0x%x) to node %u\n", ret, DLM_FINALIZE_RECO_MSG,
2789 			     dlm->key, nodenum);
2790 			if (dlm_is_host_down(ret)) {
2791 				/* this has no effect on this recovery
2792 				 * session, so set the status to zero to
2793 				 * finish out the last recovery */
2794 				mlog(ML_ERROR, "node %u went down after this "
2795 				     "node finished recovery.\n", nodenum);
2796 				ret = 0;
2797 				continue;
2798 			}
2799 			break;
2800 		}
2801 	}
2802 	if (stage == 1) {
2803 		/* reset the node_iter back to the top and send finalize2 */
2804 		iter.curnode = -1;
2805 		stage = 2;
2806 		goto stage2;
2807 	}
2808 
2809 	return ret;
2810 }
2811 
2812 int dlm_finalize_reco_handler(struct o2net_msg *msg, u32 len, void *data,
2813 			      void **ret_data)
2814 {
2815 	struct dlm_ctxt *dlm = data;
2816 	struct dlm_finalize_reco *fr = (struct dlm_finalize_reco *)msg->buf;
2817 	int stage = 1;
2818 
2819 	/* ok to return 0, domain has gone away */
2820 	if (!dlm_grab(dlm))
2821 		return 0;
2822 
2823 	if (fr->flags & DLM_FINALIZE_STAGE2)
2824 		stage = 2;
2825 
2826 	mlog(0, "%s: node %u finalizing recovery stage%d of "
2827 	     "node %u (%u:%u)\n", dlm->name, fr->node_idx, stage,
2828 	     fr->dead_node, dlm->reco.dead_node, dlm->reco.new_master);
2829 
2830 	spin_lock(&dlm->spinlock);
2831 
2832 	if (dlm->reco.new_master != fr->node_idx) {
2833 		mlog(ML_ERROR, "node %u sent recovery finalize msg, but node "
2834 		     "%u is supposed to be the new master, dead=%u\n",
2835 		     fr->node_idx, dlm->reco.new_master, fr->dead_node);
2836 		BUG();
2837 	}
2838 	if (dlm->reco.dead_node != fr->dead_node) {
2839 		mlog(ML_ERROR, "node %u sent recovery finalize msg for dead "
2840 		     "node %u, but node %u is supposed to be dead\n",
2841 		     fr->node_idx, fr->dead_node, dlm->reco.dead_node);
2842 		BUG();
2843 	}
2844 
2845 	switch (stage) {
2846 		case 1:
2847 			dlm_finish_local_lockres_recovery(dlm, fr->dead_node, fr->node_idx);
2848 			if (dlm->reco.state & DLM_RECO_STATE_FINALIZE) {
2849 				mlog(ML_ERROR, "%s: received finalize1 from "
2850 				     "new master %u for dead node %u, but "
2851 				     "this node has already received it!\n",
2852 				     dlm->name, fr->node_idx, fr->dead_node);
2853 				dlm_print_reco_node_status(dlm);
2854 				BUG();
2855 			}
2856 			dlm->reco.state |= DLM_RECO_STATE_FINALIZE;
2857 			spin_unlock(&dlm->spinlock);
2858 			break;
2859 		case 2:
2860 			if (!(dlm->reco.state & DLM_RECO_STATE_FINALIZE)) {
2861 				mlog(ML_ERROR, "%s: received finalize2 from "
2862 				     "new master %u for dead node %u, but "
2863 				     "this node did not have finalize1!\n",
2864 				     dlm->name, fr->node_idx, fr->dead_node);
2865 				dlm_print_reco_node_status(dlm);
2866 				BUG();
2867 			}
2868 			dlm->reco.state &= ~DLM_RECO_STATE_FINALIZE;
2869 			spin_unlock(&dlm->spinlock);
2870 			dlm_reset_recovery(dlm);
2871 			dlm_kick_recovery_thread(dlm);
2872 			break;
2873 		default:
2874 			BUG();
2875 	}
2876 
2877 	mlog(0, "%s: recovery done, reco master was %u, dead now %u, master now %u\n",
2878 	     dlm->name, fr->node_idx, dlm->reco.dead_node, dlm->reco.new_master);
2879 
2880 	dlm_put(dlm);
2881 	return 0;
2882 }
2883