xref: /openbmc/linux/fs/ocfs2/dlm/dlmrecovery.c (revision 4800cd83)
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 int dlm_wait_for_node_death(struct dlm_ctxt *dlm, u8 node, int timeout)
366 {
367 	if (timeout) {
368 		mlog(ML_NOTICE, "%s: waiting %dms for notification of "
369 		     "death of node %u\n", dlm->name, timeout, node);
370 		wait_event_timeout(dlm->dlm_reco_thread_wq,
371 			   dlm_is_node_dead(dlm, node),
372 			   msecs_to_jiffies(timeout));
373 	} else {
374 		mlog(ML_NOTICE, "%s: waiting indefinitely for notification "
375 		     "of death of node %u\n", dlm->name, node);
376 		wait_event(dlm->dlm_reco_thread_wq,
377 			   dlm_is_node_dead(dlm, node));
378 	}
379 	/* for now, return 0 */
380 	return 0;
381 }
382 
383 int dlm_wait_for_node_recovery(struct dlm_ctxt *dlm, u8 node, int timeout)
384 {
385 	if (timeout) {
386 		mlog(0, "%s: waiting %dms for notification of "
387 		     "recovery of node %u\n", dlm->name, timeout, node);
388 		wait_event_timeout(dlm->dlm_reco_thread_wq,
389 			   dlm_is_node_recovered(dlm, node),
390 			   msecs_to_jiffies(timeout));
391 	} else {
392 		mlog(0, "%s: waiting indefinitely for notification "
393 		     "of recovery of node %u\n", dlm->name, node);
394 		wait_event(dlm->dlm_reco_thread_wq,
395 			   dlm_is_node_recovered(dlm, node));
396 	}
397 	/* for now, return 0 */
398 	return 0;
399 }
400 
401 /* callers of the top-level api calls (dlmlock/dlmunlock) should
402  * block on the dlm->reco.event when recovery is in progress.
403  * the dlm recovery thread will set this state when it begins
404  * recovering a dead node (as the new master or not) and clear
405  * the state and wake as soon as all affected lock resources have
406  * been marked with the RECOVERY flag */
407 static int dlm_in_recovery(struct dlm_ctxt *dlm)
408 {
409 	int in_recovery;
410 	spin_lock(&dlm->spinlock);
411 	in_recovery = !!(dlm->reco.state & DLM_RECO_STATE_ACTIVE);
412 	spin_unlock(&dlm->spinlock);
413 	return in_recovery;
414 }
415 
416 
417 void dlm_wait_for_recovery(struct dlm_ctxt *dlm)
418 {
419 	if (dlm_in_recovery(dlm)) {
420 		mlog(0, "%s: reco thread %d in recovery: "
421 		     "state=%d, master=%u, dead=%u\n",
422 		     dlm->name, task_pid_nr(dlm->dlm_reco_thread_task),
423 		     dlm->reco.state, dlm->reco.new_master,
424 		     dlm->reco.dead_node);
425 	}
426 	wait_event(dlm->reco.event, !dlm_in_recovery(dlm));
427 }
428 
429 static void dlm_begin_recovery(struct dlm_ctxt *dlm)
430 {
431 	spin_lock(&dlm->spinlock);
432 	BUG_ON(dlm->reco.state & DLM_RECO_STATE_ACTIVE);
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 	wake_up(&dlm->reco.event);
444 }
445 
446 static int dlm_do_recovery(struct dlm_ctxt *dlm)
447 {
448 	int status = 0;
449 	int ret;
450 
451 	spin_lock(&dlm->spinlock);
452 
453 	/* check to see if the new master has died */
454 	if (dlm->reco.new_master != O2NM_INVALID_NODE_NUM &&
455 	    test_bit(dlm->reco.new_master, dlm->recovery_map)) {
456 		mlog(0, "new master %u died while recovering %u!\n",
457 		     dlm->reco.new_master, dlm->reco.dead_node);
458 		/* unset the new_master, leave dead_node */
459 		dlm_set_reco_master(dlm, O2NM_INVALID_NODE_NUM);
460 	}
461 
462 	/* select a target to recover */
463 	if (dlm->reco.dead_node == O2NM_INVALID_NODE_NUM) {
464 		int bit;
465 
466 		bit = find_next_bit (dlm->recovery_map, O2NM_MAX_NODES, 0);
467 		if (bit >= O2NM_MAX_NODES || bit < 0)
468 			dlm_set_reco_dead_node(dlm, O2NM_INVALID_NODE_NUM);
469 		else
470 			dlm_set_reco_dead_node(dlm, bit);
471 	} else if (!test_bit(dlm->reco.dead_node, dlm->recovery_map)) {
472 		/* BUG? */
473 		mlog(ML_ERROR, "dead_node %u no longer in recovery map!\n",
474 		     dlm->reco.dead_node);
475 		dlm_set_reco_dead_node(dlm, O2NM_INVALID_NODE_NUM);
476 	}
477 
478 	if (dlm->reco.dead_node == O2NM_INVALID_NODE_NUM) {
479 		// mlog(0, "nothing to recover!  sleeping now!\n");
480 		spin_unlock(&dlm->spinlock);
481 		/* return to main thread loop and sleep. */
482 		return 0;
483 	}
484 	mlog(0, "%s(%d):recovery thread found node %u in the recovery map!\n",
485 	     dlm->name, task_pid_nr(dlm->dlm_reco_thread_task),
486 	     dlm->reco.dead_node);
487 	spin_unlock(&dlm->spinlock);
488 
489 	/* take write barrier */
490 	/* (stops the list reshuffling thread, proxy ast handling) */
491 	dlm_begin_recovery(dlm);
492 
493 	if (dlm->reco.new_master == dlm->node_num)
494 		goto master_here;
495 
496 	if (dlm->reco.new_master == O2NM_INVALID_NODE_NUM) {
497 		/* choose a new master, returns 0 if this node
498 		 * is the master, -EEXIST if it's another node.
499 		 * this does not return until a new master is chosen
500 		 * or recovery completes entirely. */
501 		ret = dlm_pick_recovery_master(dlm);
502 		if (!ret) {
503 			/* already notified everyone.  go. */
504 			goto master_here;
505 		}
506 		mlog(0, "another node will master this recovery session.\n");
507 	}
508 	mlog(0, "dlm=%s (%d), new_master=%u, this node=%u, dead_node=%u\n",
509 	     dlm->name, task_pid_nr(dlm->dlm_reco_thread_task), dlm->reco.new_master,
510 	     dlm->node_num, dlm->reco.dead_node);
511 
512 	/* it is safe to start everything back up here
513 	 * because all of the dead node's lock resources
514 	 * have been marked as in-recovery */
515 	dlm_end_recovery(dlm);
516 
517 	/* sleep out in main dlm_recovery_thread loop. */
518 	return 0;
519 
520 master_here:
521 	mlog(ML_NOTICE, "(%d) Node %u is the Recovery Master for the Dead Node "
522 	     "%u for Domain %s\n", task_pid_nr(dlm->dlm_reco_thread_task),
523 	     dlm->node_num, dlm->reco.dead_node, dlm->name);
524 
525 	status = dlm_remaster_locks(dlm, dlm->reco.dead_node);
526 	if (status < 0) {
527 		/* we should never hit this anymore */
528 		mlog(ML_ERROR, "error %d remastering locks for node %u, "
529 		     "retrying.\n", status, dlm->reco.dead_node);
530 		/* yield a bit to allow any final network messages
531 		 * to get handled on remaining nodes */
532 		msleep(100);
533 	} else {
534 		/* success!  see if any other nodes need recovery */
535 		mlog(0, "DONE mastering recovery of %s:%u here(this=%u)!\n",
536 		     dlm->name, dlm->reco.dead_node, dlm->node_num);
537 		dlm_reset_recovery(dlm);
538 	}
539 	dlm_end_recovery(dlm);
540 
541 	/* continue and look for another dead node */
542 	return -EAGAIN;
543 }
544 
545 static int dlm_remaster_locks(struct dlm_ctxt *dlm, u8 dead_node)
546 {
547 	int status = 0;
548 	struct dlm_reco_node_data *ndata;
549 	int all_nodes_done;
550 	int destroy = 0;
551 	int pass = 0;
552 
553 	do {
554 		/* we have become recovery master.  there is no escaping
555 		 * this, so just keep trying until we get it. */
556 		status = dlm_init_recovery_area(dlm, dead_node);
557 		if (status < 0) {
558 			mlog(ML_ERROR, "%s: failed to alloc recovery area, "
559 			     "retrying\n", dlm->name);
560 			msleep(1000);
561 		}
562 	} while (status != 0);
563 
564 	/* safe to access the node data list without a lock, since this
565 	 * process is the only one to change the list */
566 	list_for_each_entry(ndata, &dlm->reco.node_data, list) {
567 		BUG_ON(ndata->state != DLM_RECO_NODE_DATA_INIT);
568 		ndata->state = DLM_RECO_NODE_DATA_REQUESTING;
569 
570 		mlog(0, "requesting lock info from node %u\n",
571 		     ndata->node_num);
572 
573 		if (ndata->node_num == dlm->node_num) {
574 			ndata->state = DLM_RECO_NODE_DATA_DONE;
575 			continue;
576 		}
577 
578 		do {
579 			status = dlm_request_all_locks(dlm, ndata->node_num,
580 						       dead_node);
581 			if (status < 0) {
582 				mlog_errno(status);
583 				if (dlm_is_host_down(status)) {
584 					/* node died, ignore it for recovery */
585 					status = 0;
586 					ndata->state = DLM_RECO_NODE_DATA_DEAD;
587 					/* wait for the domain map to catch up
588 					 * with the network state. */
589 					wait_event_timeout(dlm->dlm_reco_thread_wq,
590 							   dlm_is_node_dead(dlm,
591 								ndata->node_num),
592 							   msecs_to_jiffies(1000));
593 					mlog(0, "waited 1 sec for %u, "
594 					     "dead? %s\n", ndata->node_num,
595 					     dlm_is_node_dead(dlm, ndata->node_num) ?
596 					     "yes" : "no");
597 				} else {
598 					/* -ENOMEM on the other node */
599 					mlog(0, "%s: node %u returned "
600 					     "%d during recovery, retrying "
601 					     "after a short wait\n",
602 					     dlm->name, ndata->node_num,
603 					     status);
604 					msleep(100);
605 				}
606 			}
607 		} while (status != 0);
608 
609 		spin_lock(&dlm_reco_state_lock);
610 		switch (ndata->state) {
611 			case DLM_RECO_NODE_DATA_INIT:
612 			case DLM_RECO_NODE_DATA_FINALIZE_SENT:
613 			case DLM_RECO_NODE_DATA_REQUESTED:
614 				BUG();
615 				break;
616 			case DLM_RECO_NODE_DATA_DEAD:
617 				mlog(0, "node %u died after requesting "
618 				     "recovery info for node %u\n",
619 				     ndata->node_num, dead_node);
620 				/* fine.  don't need this node's info.
621 				 * continue without it. */
622 				break;
623 			case DLM_RECO_NODE_DATA_REQUESTING:
624 				ndata->state = DLM_RECO_NODE_DATA_REQUESTED;
625 				mlog(0, "now receiving recovery data from "
626 				     "node %u for dead node %u\n",
627 				     ndata->node_num, dead_node);
628 				break;
629 			case DLM_RECO_NODE_DATA_RECEIVING:
630 				mlog(0, "already receiving recovery data from "
631 				     "node %u for dead node %u\n",
632 				     ndata->node_num, dead_node);
633 				break;
634 			case DLM_RECO_NODE_DATA_DONE:
635 				mlog(0, "already DONE receiving recovery data "
636 				     "from node %u for dead node %u\n",
637 				     ndata->node_num, dead_node);
638 				break;
639 		}
640 		spin_unlock(&dlm_reco_state_lock);
641 	}
642 
643 	mlog(0, "done requesting all lock info\n");
644 
645 	/* nodes should be sending reco data now
646 	 * just need to wait */
647 
648 	while (1) {
649 		/* check all the nodes now to see if we are
650 		 * done, or if anyone died */
651 		all_nodes_done = 1;
652 		spin_lock(&dlm_reco_state_lock);
653 		list_for_each_entry(ndata, &dlm->reco.node_data, list) {
654 			mlog(0, "checking recovery state of node %u\n",
655 			     ndata->node_num);
656 			switch (ndata->state) {
657 				case DLM_RECO_NODE_DATA_INIT:
658 				case DLM_RECO_NODE_DATA_REQUESTING:
659 					mlog(ML_ERROR, "bad ndata state for "
660 					     "node %u: state=%d\n",
661 					     ndata->node_num, ndata->state);
662 					BUG();
663 					break;
664 				case DLM_RECO_NODE_DATA_DEAD:
665 					mlog(0, "node %u died after "
666 					     "requesting recovery info for "
667 					     "node %u\n", ndata->node_num,
668 					     dead_node);
669 					break;
670 				case DLM_RECO_NODE_DATA_RECEIVING:
671 				case DLM_RECO_NODE_DATA_REQUESTED:
672 					mlog(0, "%s: node %u still in state %s\n",
673 					     dlm->name, ndata->node_num,
674 					     ndata->state==DLM_RECO_NODE_DATA_RECEIVING ?
675 					     "receiving" : "requested");
676 					all_nodes_done = 0;
677 					break;
678 				case DLM_RECO_NODE_DATA_DONE:
679 					mlog(0, "%s: node %u state is done\n",
680 					     dlm->name, ndata->node_num);
681 					break;
682 				case DLM_RECO_NODE_DATA_FINALIZE_SENT:
683 					mlog(0, "%s: node %u state is finalize\n",
684 					     dlm->name, ndata->node_num);
685 					break;
686 			}
687 		}
688 		spin_unlock(&dlm_reco_state_lock);
689 
690 		mlog(0, "pass #%d, all_nodes_done?: %s\n", ++pass,
691 		     all_nodes_done?"yes":"no");
692 		if (all_nodes_done) {
693 			int ret;
694 
695 			/* all nodes are now in DLM_RECO_NODE_DATA_DONE state
696 	 		 * just send a finalize message to everyone and
697 	 		 * clean up */
698 			mlog(0, "all nodes are done! send finalize\n");
699 			ret = dlm_send_finalize_reco_message(dlm);
700 			if (ret < 0)
701 				mlog_errno(ret);
702 
703 			spin_lock(&dlm->spinlock);
704 			dlm_finish_local_lockres_recovery(dlm, dead_node,
705 							  dlm->node_num);
706 			spin_unlock(&dlm->spinlock);
707 			mlog(0, "should be done with recovery!\n");
708 
709 			mlog(0, "finishing recovery of %s at %lu, "
710 			     "dead=%u, this=%u, new=%u\n", dlm->name,
711 			     jiffies, dlm->reco.dead_node,
712 			     dlm->node_num, dlm->reco.new_master);
713 			destroy = 1;
714 			status = 0;
715 			/* rescan everything marked dirty along the way */
716 			dlm_kick_thread(dlm, NULL);
717 			break;
718 		}
719 		/* wait to be signalled, with periodic timeout
720 		 * to check for node death */
721 		wait_event_interruptible_timeout(dlm->dlm_reco_thread_wq,
722 					 kthread_should_stop(),
723 					 msecs_to_jiffies(DLM_RECO_THREAD_TIMEOUT_MS));
724 
725 	}
726 
727 	if (destroy)
728 		dlm_destroy_recovery_area(dlm, dead_node);
729 
730 	mlog_exit(status);
731 	return status;
732 }
733 
734 static int dlm_init_recovery_area(struct dlm_ctxt *dlm, u8 dead_node)
735 {
736 	int num=0;
737 	struct dlm_reco_node_data *ndata;
738 
739 	spin_lock(&dlm->spinlock);
740 	memcpy(dlm->reco.node_map, dlm->domain_map, sizeof(dlm->domain_map));
741 	/* nodes can only be removed (by dying) after dropping
742 	 * this lock, and death will be trapped later, so this should do */
743 	spin_unlock(&dlm->spinlock);
744 
745 	while (1) {
746 		num = find_next_bit (dlm->reco.node_map, O2NM_MAX_NODES, num);
747 		if (num >= O2NM_MAX_NODES) {
748 			break;
749 		}
750 		BUG_ON(num == dead_node);
751 
752 		ndata = kzalloc(sizeof(*ndata), GFP_NOFS);
753 		if (!ndata) {
754 			dlm_destroy_recovery_area(dlm, dead_node);
755 			return -ENOMEM;
756 		}
757 		ndata->node_num = num;
758 		ndata->state = DLM_RECO_NODE_DATA_INIT;
759 		spin_lock(&dlm_reco_state_lock);
760 		list_add_tail(&ndata->list, &dlm->reco.node_data);
761 		spin_unlock(&dlm_reco_state_lock);
762 		num++;
763 	}
764 
765 	return 0;
766 }
767 
768 static void dlm_destroy_recovery_area(struct dlm_ctxt *dlm, u8 dead_node)
769 {
770 	struct dlm_reco_node_data *ndata, *next;
771 	LIST_HEAD(tmplist);
772 
773 	spin_lock(&dlm_reco_state_lock);
774 	list_splice_init(&dlm->reco.node_data, &tmplist);
775 	spin_unlock(&dlm_reco_state_lock);
776 
777 	list_for_each_entry_safe(ndata, next, &tmplist, list) {
778 		list_del_init(&ndata->list);
779 		kfree(ndata);
780 	}
781 }
782 
783 static int dlm_request_all_locks(struct dlm_ctxt *dlm, u8 request_from,
784 				 u8 dead_node)
785 {
786 	struct dlm_lock_request lr;
787 	enum dlm_status ret;
788 
789 	mlog(0, "\n");
790 
791 
792 	mlog(0, "dlm_request_all_locks: dead node is %u, sending request "
793 		  "to %u\n", dead_node, request_from);
794 
795 	memset(&lr, 0, sizeof(lr));
796 	lr.node_idx = dlm->node_num;
797 	lr.dead_node = dead_node;
798 
799 	// send message
800 	ret = DLM_NOLOCKMGR;
801 	ret = o2net_send_message(DLM_LOCK_REQUEST_MSG, dlm->key,
802 				 &lr, sizeof(lr), request_from, NULL);
803 
804 	/* negative status is handled by caller */
805 	if (ret < 0)
806 		mlog(ML_ERROR, "Error %d when sending message %u (key "
807 		     "0x%x) to node %u\n", ret, DLM_LOCK_REQUEST_MSG,
808 		     dlm->key, request_from);
809 
810 	// return from here, then
811 	// sleep until all received or error
812 	return ret;
813 
814 }
815 
816 int dlm_request_all_locks_handler(struct o2net_msg *msg, u32 len, void *data,
817 				  void **ret_data)
818 {
819 	struct dlm_ctxt *dlm = data;
820 	struct dlm_lock_request *lr = (struct dlm_lock_request *)msg->buf;
821 	char *buf = NULL;
822 	struct dlm_work_item *item = NULL;
823 
824 	if (!dlm_grab(dlm))
825 		return -EINVAL;
826 
827 	if (lr->dead_node != dlm->reco.dead_node) {
828 		mlog(ML_ERROR, "%s: node %u sent dead_node=%u, but local "
829 		     "dead_node is %u\n", dlm->name, lr->node_idx,
830 		     lr->dead_node, dlm->reco.dead_node);
831 		dlm_print_reco_node_status(dlm);
832 		/* this is a hack */
833 		dlm_put(dlm);
834 		return -ENOMEM;
835 	}
836 	BUG_ON(lr->dead_node != dlm->reco.dead_node);
837 
838 	item = kzalloc(sizeof(*item), GFP_NOFS);
839 	if (!item) {
840 		dlm_put(dlm);
841 		return -ENOMEM;
842 	}
843 
844 	/* this will get freed by dlm_request_all_locks_worker */
845 	buf = (char *) __get_free_page(GFP_NOFS);
846 	if (!buf) {
847 		kfree(item);
848 		dlm_put(dlm);
849 		return -ENOMEM;
850 	}
851 
852 	/* queue up work for dlm_request_all_locks_worker */
853 	dlm_grab(dlm);  /* get an extra ref for the work item */
854 	dlm_init_work_item(dlm, item, dlm_request_all_locks_worker, buf);
855 	item->u.ral.reco_master = lr->node_idx;
856 	item->u.ral.dead_node = lr->dead_node;
857 	spin_lock(&dlm->work_lock);
858 	list_add_tail(&item->list, &dlm->work_list);
859 	spin_unlock(&dlm->work_lock);
860 	queue_work(dlm->dlm_worker, &dlm->dispatched_work);
861 
862 	dlm_put(dlm);
863 	return 0;
864 }
865 
866 static void dlm_request_all_locks_worker(struct dlm_work_item *item, void *data)
867 {
868 	struct dlm_migratable_lockres *mres;
869 	struct dlm_lock_resource *res;
870 	struct dlm_ctxt *dlm;
871 	LIST_HEAD(resources);
872 	int ret;
873 	u8 dead_node, reco_master;
874 	int skip_all_done = 0;
875 
876 	dlm = item->dlm;
877 	dead_node = item->u.ral.dead_node;
878 	reco_master = item->u.ral.reco_master;
879 	mres = (struct dlm_migratable_lockres *)data;
880 
881 	mlog(0, "%s: recovery worker started, dead=%u, master=%u\n",
882 	     dlm->name, dead_node, reco_master);
883 
884 	if (dead_node != dlm->reco.dead_node ||
885 	    reco_master != dlm->reco.new_master) {
886 		/* worker could have been created before the recovery master
887 		 * died.  if so, do not continue, but do not error. */
888 		if (dlm->reco.new_master == O2NM_INVALID_NODE_NUM) {
889 			mlog(ML_NOTICE, "%s: will not send recovery state, "
890 			     "recovery master %u died, thread=(dead=%u,mas=%u)"
891 			     " current=(dead=%u,mas=%u)\n", dlm->name,
892 			     reco_master, dead_node, reco_master,
893 			     dlm->reco.dead_node, dlm->reco.new_master);
894 		} else {
895 			mlog(ML_NOTICE, "%s: reco state invalid: reco(dead=%u, "
896 			     "master=%u), request(dead=%u, master=%u)\n",
897 			     dlm->name, dlm->reco.dead_node,
898 			     dlm->reco.new_master, dead_node, reco_master);
899 		}
900 		goto leave;
901 	}
902 
903 	/* lock resources should have already been moved to the
904  	 * dlm->reco.resources list.  now move items from that list
905  	 * to a temp list if the dead owner matches.  note that the
906 	 * whole cluster recovers only one node at a time, so we
907 	 * can safely move UNKNOWN lock resources for each recovery
908 	 * session. */
909 	dlm_move_reco_locks_to_list(dlm, &resources, dead_node);
910 
911 	/* now we can begin blasting lockreses without the dlm lock */
912 
913 	/* any errors returned will be due to the new_master dying,
914 	 * the dlm_reco_thread should detect this */
915 	list_for_each_entry(res, &resources, recovering) {
916 		ret = dlm_send_one_lockres(dlm, res, mres, reco_master,
917 				   	DLM_MRES_RECOVERY);
918 		if (ret < 0) {
919 			mlog(ML_ERROR, "%s: node %u went down while sending "
920 			     "recovery state for dead node %u, ret=%d\n", dlm->name,
921 			     reco_master, dead_node, ret);
922 			skip_all_done = 1;
923 			break;
924 		}
925 	}
926 
927 	/* move the resources back to the list */
928 	spin_lock(&dlm->spinlock);
929 	list_splice_init(&resources, &dlm->reco.resources);
930 	spin_unlock(&dlm->spinlock);
931 
932 	if (!skip_all_done) {
933 		ret = dlm_send_all_done_msg(dlm, dead_node, reco_master);
934 		if (ret < 0) {
935 			mlog(ML_ERROR, "%s: node %u went down while sending "
936 			     "recovery all-done for dead node %u, ret=%d\n",
937 			     dlm->name, reco_master, dead_node, ret);
938 		}
939 	}
940 leave:
941 	free_page((unsigned long)data);
942 }
943 
944 
945 static int dlm_send_all_done_msg(struct dlm_ctxt *dlm, u8 dead_node, u8 send_to)
946 {
947 	int ret, tmpret;
948 	struct dlm_reco_data_done done_msg;
949 
950 	memset(&done_msg, 0, sizeof(done_msg));
951 	done_msg.node_idx = dlm->node_num;
952 	done_msg.dead_node = dead_node;
953 	mlog(0, "sending DATA DONE message to %u, "
954 	     "my node=%u, dead node=%u\n", send_to, done_msg.node_idx,
955 	     done_msg.dead_node);
956 
957 	ret = o2net_send_message(DLM_RECO_DATA_DONE_MSG, dlm->key, &done_msg,
958 				 sizeof(done_msg), send_to, &tmpret);
959 	if (ret < 0) {
960 		mlog(ML_ERROR, "Error %d when sending message %u (key "
961 		     "0x%x) to node %u\n", ret, DLM_RECO_DATA_DONE_MSG,
962 		     dlm->key, send_to);
963 		if (!dlm_is_host_down(ret)) {
964 			BUG();
965 		}
966 	} else
967 		ret = tmpret;
968 	return ret;
969 }
970 
971 
972 int dlm_reco_data_done_handler(struct o2net_msg *msg, u32 len, void *data,
973 			       void **ret_data)
974 {
975 	struct dlm_ctxt *dlm = data;
976 	struct dlm_reco_data_done *done = (struct dlm_reco_data_done *)msg->buf;
977 	struct dlm_reco_node_data *ndata = NULL;
978 	int ret = -EINVAL;
979 
980 	if (!dlm_grab(dlm))
981 		return -EINVAL;
982 
983 	mlog(0, "got DATA DONE: dead_node=%u, reco.dead_node=%u, "
984 	     "node_idx=%u, this node=%u\n", done->dead_node,
985 	     dlm->reco.dead_node, done->node_idx, dlm->node_num);
986 
987 	mlog_bug_on_msg((done->dead_node != dlm->reco.dead_node),
988 			"Got DATA DONE: dead_node=%u, reco.dead_node=%u, "
989 			"node_idx=%u, this node=%u\n", done->dead_node,
990 			dlm->reco.dead_node, done->node_idx, dlm->node_num);
991 
992 	spin_lock(&dlm_reco_state_lock);
993 	list_for_each_entry(ndata, &dlm->reco.node_data, list) {
994 		if (ndata->node_num != done->node_idx)
995 			continue;
996 
997 		switch (ndata->state) {
998 			/* should have moved beyond INIT but not to FINALIZE yet */
999 			case DLM_RECO_NODE_DATA_INIT:
1000 			case DLM_RECO_NODE_DATA_DEAD:
1001 			case DLM_RECO_NODE_DATA_FINALIZE_SENT:
1002 				mlog(ML_ERROR, "bad ndata state for node %u:"
1003 				     " state=%d\n", ndata->node_num,
1004 				     ndata->state);
1005 				BUG();
1006 				break;
1007 			/* these states are possible at this point, anywhere along
1008 			 * the line of recovery */
1009 			case DLM_RECO_NODE_DATA_DONE:
1010 			case DLM_RECO_NODE_DATA_RECEIVING:
1011 			case DLM_RECO_NODE_DATA_REQUESTED:
1012 			case DLM_RECO_NODE_DATA_REQUESTING:
1013 				mlog(0, "node %u is DONE sending "
1014 					  "recovery data!\n",
1015 					  ndata->node_num);
1016 
1017 				ndata->state = DLM_RECO_NODE_DATA_DONE;
1018 				ret = 0;
1019 				break;
1020 		}
1021 	}
1022 	spin_unlock(&dlm_reco_state_lock);
1023 
1024 	/* wake the recovery thread, some node is done */
1025 	if (!ret)
1026 		dlm_kick_recovery_thread(dlm);
1027 
1028 	if (ret < 0)
1029 		mlog(ML_ERROR, "failed to find recovery node data for node "
1030 		     "%u\n", done->node_idx);
1031 	dlm_put(dlm);
1032 
1033 	mlog(0, "leaving reco data done handler, ret=%d\n", ret);
1034 	return ret;
1035 }
1036 
1037 static void dlm_move_reco_locks_to_list(struct dlm_ctxt *dlm,
1038 					struct list_head *list,
1039 				       	u8 dead_node)
1040 {
1041 	struct dlm_lock_resource *res, *next;
1042 	struct dlm_lock *lock;
1043 
1044 	spin_lock(&dlm->spinlock);
1045 	list_for_each_entry_safe(res, next, &dlm->reco.resources, recovering) {
1046 		/* always prune any $RECOVERY entries for dead nodes,
1047 		 * otherwise hangs can occur during later recovery */
1048 		if (dlm_is_recovery_lock(res->lockname.name,
1049 					 res->lockname.len)) {
1050 			spin_lock(&res->spinlock);
1051 			list_for_each_entry(lock, &res->granted, list) {
1052 				if (lock->ml.node == dead_node) {
1053 					mlog(0, "AHA! there was "
1054 					     "a $RECOVERY lock for dead "
1055 					     "node %u (%s)!\n",
1056 					     dead_node, dlm->name);
1057 					list_del_init(&lock->list);
1058 					dlm_lock_put(lock);
1059 					break;
1060 				}
1061 			}
1062 			spin_unlock(&res->spinlock);
1063 			continue;
1064 		}
1065 
1066 		if (res->owner == dead_node) {
1067 			mlog(0, "found lockres owned by dead node while "
1068 				  "doing recovery for node %u. sending it.\n",
1069 				  dead_node);
1070 			list_move_tail(&res->recovering, list);
1071 		} else if (res->owner == DLM_LOCK_RES_OWNER_UNKNOWN) {
1072 			mlog(0, "found UNKNOWN owner while doing recovery "
1073 				  "for node %u. sending it.\n", dead_node);
1074 			list_move_tail(&res->recovering, list);
1075 		}
1076 	}
1077 	spin_unlock(&dlm->spinlock);
1078 }
1079 
1080 static inline int dlm_num_locks_in_lockres(struct dlm_lock_resource *res)
1081 {
1082 	int total_locks = 0;
1083 	struct list_head *iter, *queue = &res->granted;
1084 	int i;
1085 
1086 	for (i=0; i<3; i++) {
1087 		list_for_each(iter, queue)
1088 			total_locks++;
1089 		queue++;
1090 	}
1091 	return total_locks;
1092 }
1093 
1094 
1095 static int dlm_send_mig_lockres_msg(struct dlm_ctxt *dlm,
1096 				      struct dlm_migratable_lockres *mres,
1097 				      u8 send_to,
1098 				      struct dlm_lock_resource *res,
1099 				      int total_locks)
1100 {
1101 	u64 mig_cookie = be64_to_cpu(mres->mig_cookie);
1102 	int mres_total_locks = be32_to_cpu(mres->total_locks);
1103 	int sz, ret = 0, status = 0;
1104 	u8 orig_flags = mres->flags,
1105 	   orig_master = mres->master;
1106 
1107 	BUG_ON(mres->num_locks > DLM_MAX_MIGRATABLE_LOCKS);
1108 	if (!mres->num_locks)
1109 		return 0;
1110 
1111 	sz = sizeof(struct dlm_migratable_lockres) +
1112 		(mres->num_locks * sizeof(struct dlm_migratable_lock));
1113 
1114 	/* add an all-done flag if we reached the last lock */
1115 	orig_flags = mres->flags;
1116 	BUG_ON(total_locks > mres_total_locks);
1117 	if (total_locks == mres_total_locks)
1118 		mres->flags |= DLM_MRES_ALL_DONE;
1119 
1120 	mlog(0, "%s:%.*s: sending mig lockres (%s) to %u\n",
1121 	     dlm->name, res->lockname.len, res->lockname.name,
1122 	     orig_flags & DLM_MRES_MIGRATION ? "migration" : "recovery",
1123 	     send_to);
1124 
1125 	/* send it */
1126 	ret = o2net_send_message(DLM_MIG_LOCKRES_MSG, dlm->key, mres,
1127 				 sz, send_to, &status);
1128 	if (ret < 0) {
1129 		/* XXX: negative status is not handled.
1130 		 * this will end up killing this node. */
1131 		mlog(ML_ERROR, "Error %d when sending message %u (key "
1132 		     "0x%x) to node %u\n", ret, DLM_MIG_LOCKRES_MSG,
1133 		     dlm->key, send_to);
1134 	} else {
1135 		/* might get an -ENOMEM back here */
1136 		ret = status;
1137 		if (ret < 0) {
1138 			mlog_errno(ret);
1139 
1140 			if (ret == -EFAULT) {
1141 				mlog(ML_ERROR, "node %u told me to kill "
1142 				     "myself!\n", send_to);
1143 				BUG();
1144 			}
1145 		}
1146 	}
1147 
1148 	/* zero and reinit the message buffer */
1149 	dlm_init_migratable_lockres(mres, res->lockname.name,
1150 				    res->lockname.len, mres_total_locks,
1151 				    mig_cookie, orig_flags, orig_master);
1152 	return ret;
1153 }
1154 
1155 static void dlm_init_migratable_lockres(struct dlm_migratable_lockres *mres,
1156 					const char *lockname, int namelen,
1157 					int total_locks, u64 cookie,
1158 					u8 flags, u8 master)
1159 {
1160 	/* mres here is one full page */
1161 	clear_page(mres);
1162 	mres->lockname_len = namelen;
1163 	memcpy(mres->lockname, lockname, namelen);
1164 	mres->num_locks = 0;
1165 	mres->total_locks = cpu_to_be32(total_locks);
1166 	mres->mig_cookie = cpu_to_be64(cookie);
1167 	mres->flags = flags;
1168 	mres->master = master;
1169 }
1170 
1171 static void dlm_prepare_lvb_for_migration(struct dlm_lock *lock,
1172 					  struct dlm_migratable_lockres *mres,
1173 					  int queue)
1174 {
1175 	if (!lock->lksb)
1176 	       return;
1177 
1178 	/* Ignore lvb in all locks in the blocked list */
1179 	if (queue == DLM_BLOCKED_LIST)
1180 		return;
1181 
1182 	/* Only consider lvbs in locks with granted EX or PR lock levels */
1183 	if (lock->ml.type != LKM_EXMODE && lock->ml.type != LKM_PRMODE)
1184 		return;
1185 
1186 	if (dlm_lvb_is_empty(mres->lvb)) {
1187 		memcpy(mres->lvb, lock->lksb->lvb, DLM_LVB_LEN);
1188 		return;
1189 	}
1190 
1191 	/* Ensure the lvb copied for migration matches in other valid locks */
1192 	if (!memcmp(mres->lvb, lock->lksb->lvb, DLM_LVB_LEN))
1193 		return;
1194 
1195 	mlog(ML_ERROR, "Mismatched lvb in lock cookie=%u:%llu, name=%.*s, "
1196 	     "node=%u\n",
1197 	     dlm_get_lock_cookie_node(be64_to_cpu(lock->ml.cookie)),
1198 	     dlm_get_lock_cookie_seq(be64_to_cpu(lock->ml.cookie)),
1199 	     lock->lockres->lockname.len, lock->lockres->lockname.name,
1200 	     lock->ml.node);
1201 	dlm_print_one_lock_resource(lock->lockres);
1202 	BUG();
1203 }
1204 
1205 /* returns 1 if this lock fills the network structure,
1206  * 0 otherwise */
1207 static int dlm_add_lock_to_array(struct dlm_lock *lock,
1208 				 struct dlm_migratable_lockres *mres, int queue)
1209 {
1210 	struct dlm_migratable_lock *ml;
1211 	int lock_num = mres->num_locks;
1212 
1213 	ml = &(mres->ml[lock_num]);
1214 	ml->cookie = lock->ml.cookie;
1215 	ml->type = lock->ml.type;
1216 	ml->convert_type = lock->ml.convert_type;
1217 	ml->highest_blocked = lock->ml.highest_blocked;
1218 	ml->list = queue;
1219 	if (lock->lksb) {
1220 		ml->flags = lock->lksb->flags;
1221 		dlm_prepare_lvb_for_migration(lock, mres, queue);
1222 	}
1223 	ml->node = lock->ml.node;
1224 	mres->num_locks++;
1225 	/* we reached the max, send this network message */
1226 	if (mres->num_locks == DLM_MAX_MIGRATABLE_LOCKS)
1227 		return 1;
1228 	return 0;
1229 }
1230 
1231 static void dlm_add_dummy_lock(struct dlm_ctxt *dlm,
1232 			       struct dlm_migratable_lockres *mres)
1233 {
1234 	struct dlm_lock dummy;
1235 	memset(&dummy, 0, sizeof(dummy));
1236 	dummy.ml.cookie = 0;
1237 	dummy.ml.type = LKM_IVMODE;
1238 	dummy.ml.convert_type = LKM_IVMODE;
1239 	dummy.ml.highest_blocked = LKM_IVMODE;
1240 	dummy.lksb = NULL;
1241 	dummy.ml.node = dlm->node_num;
1242 	dlm_add_lock_to_array(&dummy, mres, DLM_BLOCKED_LIST);
1243 }
1244 
1245 static inline int dlm_is_dummy_lock(struct dlm_ctxt *dlm,
1246 				    struct dlm_migratable_lock *ml,
1247 				    u8 *nodenum)
1248 {
1249 	if (unlikely(ml->cookie == 0 &&
1250 	    ml->type == LKM_IVMODE &&
1251 	    ml->convert_type == LKM_IVMODE &&
1252 	    ml->highest_blocked == LKM_IVMODE &&
1253 	    ml->list == DLM_BLOCKED_LIST)) {
1254 		*nodenum = ml->node;
1255 		return 1;
1256 	}
1257 	return 0;
1258 }
1259 
1260 int dlm_send_one_lockres(struct dlm_ctxt *dlm, struct dlm_lock_resource *res,
1261 			 struct dlm_migratable_lockres *mres,
1262 			 u8 send_to, u8 flags)
1263 {
1264 	struct list_head *queue;
1265 	int total_locks, i;
1266 	u64 mig_cookie = 0;
1267 	struct dlm_lock *lock;
1268 	int ret = 0;
1269 
1270 	BUG_ON(!(flags & (DLM_MRES_RECOVERY|DLM_MRES_MIGRATION)));
1271 
1272 	mlog(0, "sending to %u\n", send_to);
1273 
1274 	total_locks = dlm_num_locks_in_lockres(res);
1275 	if (total_locks > DLM_MAX_MIGRATABLE_LOCKS) {
1276 		/* rare, but possible */
1277 		mlog(0, "argh.  lockres has %d locks.  this will "
1278 			  "require more than one network packet to "
1279 			  "migrate\n", total_locks);
1280 		mig_cookie = dlm_get_next_mig_cookie();
1281 	}
1282 
1283 	dlm_init_migratable_lockres(mres, res->lockname.name,
1284 				    res->lockname.len, total_locks,
1285 				    mig_cookie, flags, res->owner);
1286 
1287 	total_locks = 0;
1288 	for (i=DLM_GRANTED_LIST; i<=DLM_BLOCKED_LIST; i++) {
1289 		queue = dlm_list_idx_to_ptr(res, i);
1290 		list_for_each_entry(lock, queue, list) {
1291 			/* add another lock. */
1292 			total_locks++;
1293 			if (!dlm_add_lock_to_array(lock, mres, i))
1294 				continue;
1295 
1296 			/* this filled the lock message,
1297 			 * we must send it immediately. */
1298 			ret = dlm_send_mig_lockres_msg(dlm, mres, send_to,
1299 						       res, total_locks);
1300 			if (ret < 0)
1301 				goto error;
1302 		}
1303 	}
1304 	if (total_locks == 0) {
1305 		/* send a dummy lock to indicate a mastery reference only */
1306 		mlog(0, "%s:%.*s: sending dummy lock to %u, %s\n",
1307 		     dlm->name, res->lockname.len, res->lockname.name,
1308 		     send_to, flags & DLM_MRES_RECOVERY ? "recovery" :
1309 		     "migration");
1310 		dlm_add_dummy_lock(dlm, mres);
1311 	}
1312 	/* flush any remaining locks */
1313 	ret = dlm_send_mig_lockres_msg(dlm, mres, send_to, res, total_locks);
1314 	if (ret < 0)
1315 		goto error;
1316 	return ret;
1317 
1318 error:
1319 	mlog(ML_ERROR, "%s: dlm_send_mig_lockres_msg returned %d\n",
1320 	     dlm->name, ret);
1321 	if (!dlm_is_host_down(ret))
1322 		BUG();
1323 	mlog(0, "%s: node %u went down while sending %s "
1324 	     "lockres %.*s\n", dlm->name, send_to,
1325 	     flags & DLM_MRES_RECOVERY ?  "recovery" : "migration",
1326 	     res->lockname.len, res->lockname.name);
1327 	return ret;
1328 }
1329 
1330 
1331 
1332 /*
1333  * this message will contain no more than one page worth of
1334  * recovery data, and it will work on only one lockres.
1335  * there may be many locks in this page, and we may need to wait
1336  * for additional packets to complete all the locks (rare, but
1337  * possible).
1338  */
1339 /*
1340  * NOTE: the allocation error cases here are scary
1341  * we really cannot afford to fail an alloc in recovery
1342  * do we spin?  returning an error only delays the problem really
1343  */
1344 
1345 int dlm_mig_lockres_handler(struct o2net_msg *msg, u32 len, void *data,
1346 			    void **ret_data)
1347 {
1348 	struct dlm_ctxt *dlm = data;
1349 	struct dlm_migratable_lockres *mres =
1350 		(struct dlm_migratable_lockres *)msg->buf;
1351 	int ret = 0;
1352 	u8 real_master;
1353 	u8 extra_refs = 0;
1354 	char *buf = NULL;
1355 	struct dlm_work_item *item = NULL;
1356 	struct dlm_lock_resource *res = NULL;
1357 
1358 	if (!dlm_grab(dlm))
1359 		return -EINVAL;
1360 
1361 	BUG_ON(!(mres->flags & (DLM_MRES_RECOVERY|DLM_MRES_MIGRATION)));
1362 
1363 	real_master = mres->master;
1364 	if (real_master == DLM_LOCK_RES_OWNER_UNKNOWN) {
1365 		/* cannot migrate a lockres with no master */
1366 		BUG_ON(!(mres->flags & DLM_MRES_RECOVERY));
1367 	}
1368 
1369 	mlog(0, "%s message received from node %u\n",
1370 		  (mres->flags & DLM_MRES_RECOVERY) ?
1371 		  "recovery" : "migration", mres->master);
1372 	if (mres->flags & DLM_MRES_ALL_DONE)
1373 		mlog(0, "all done flag.  all lockres data received!\n");
1374 
1375 	ret = -ENOMEM;
1376 	buf = kmalloc(be16_to_cpu(msg->data_len), GFP_NOFS);
1377 	item = kzalloc(sizeof(*item), GFP_NOFS);
1378 	if (!buf || !item)
1379 		goto leave;
1380 
1381 	/* lookup the lock to see if we have a secondary queue for this
1382 	 * already...  just add the locks in and this will have its owner
1383 	 * and RECOVERY flag changed when it completes. */
1384 	res = dlm_lookup_lockres(dlm, mres->lockname, mres->lockname_len);
1385 	if (res) {
1386 	 	/* this will get a ref on res */
1387 		/* mark it as recovering/migrating and hash it */
1388 		spin_lock(&res->spinlock);
1389 		if (mres->flags & DLM_MRES_RECOVERY) {
1390 			res->state |= DLM_LOCK_RES_RECOVERING;
1391 		} else {
1392 			if (res->state & DLM_LOCK_RES_MIGRATING) {
1393 				/* this is at least the second
1394 				 * lockres message */
1395 				mlog(0, "lock %.*s is already migrating\n",
1396 					  mres->lockname_len,
1397 					  mres->lockname);
1398 			} else if (res->state & DLM_LOCK_RES_RECOVERING) {
1399 				/* caller should BUG */
1400 				mlog(ML_ERROR, "node is attempting to migrate "
1401 				     "lock %.*s, but marked as recovering!\n",
1402 				     mres->lockname_len, mres->lockname);
1403 				ret = -EFAULT;
1404 				spin_unlock(&res->spinlock);
1405 				goto leave;
1406 			}
1407 			res->state |= DLM_LOCK_RES_MIGRATING;
1408 		}
1409 		spin_unlock(&res->spinlock);
1410 	} else {
1411 		/* need to allocate, just like if it was
1412 		 * mastered here normally  */
1413 		res = dlm_new_lockres(dlm, mres->lockname, mres->lockname_len);
1414 		if (!res)
1415 			goto leave;
1416 
1417 		/* to match the ref that we would have gotten if
1418 		 * dlm_lookup_lockres had succeeded */
1419 		dlm_lockres_get(res);
1420 
1421 		/* mark it as recovering/migrating and hash it */
1422 		if (mres->flags & DLM_MRES_RECOVERY)
1423 			res->state |= DLM_LOCK_RES_RECOVERING;
1424 		else
1425 			res->state |= DLM_LOCK_RES_MIGRATING;
1426 
1427 		spin_lock(&dlm->spinlock);
1428 		__dlm_insert_lockres(dlm, res);
1429 		spin_unlock(&dlm->spinlock);
1430 
1431 		/* Add an extra ref for this lock-less lockres lest the
1432 		 * dlm_thread purges it before we get the chance to add
1433 		 * locks to it */
1434 		dlm_lockres_get(res);
1435 
1436 		/* There are three refs that need to be put.
1437 		 * 1. Taken above.
1438 		 * 2. kref_init in dlm_new_lockres()->dlm_init_lockres().
1439 		 * 3. dlm_lookup_lockres()
1440 		 * The first one is handled at the end of this function. The
1441 		 * other two are handled in the worker thread after locks have
1442 		 * been attached. Yes, we don't wait for purge time to match
1443 		 * kref_init. The lockres will still have atleast one ref
1444 		 * added because it is in the hash __dlm_insert_lockres() */
1445 		extra_refs++;
1446 
1447 		/* now that the new lockres is inserted,
1448 		 * make it usable by other processes */
1449 		spin_lock(&res->spinlock);
1450 		res->state &= ~DLM_LOCK_RES_IN_PROGRESS;
1451 		spin_unlock(&res->spinlock);
1452 		wake_up(&res->wq);
1453 	}
1454 
1455 	/* at this point we have allocated everything we need,
1456 	 * and we have a hashed lockres with an extra ref and
1457 	 * the proper res->state flags. */
1458 	ret = 0;
1459 	spin_lock(&res->spinlock);
1460 	/* drop this either when master requery finds a different master
1461 	 * or when a lock is added by the recovery worker */
1462 	dlm_lockres_grab_inflight_ref(dlm, res);
1463 	if (mres->master == DLM_LOCK_RES_OWNER_UNKNOWN) {
1464 		/* migration cannot have an unknown master */
1465 		BUG_ON(!(mres->flags & DLM_MRES_RECOVERY));
1466 		mlog(0, "recovery has passed me a lockres with an "
1467 			  "unknown owner.. will need to requery: "
1468 			  "%.*s\n", mres->lockname_len, mres->lockname);
1469 	} else {
1470 		/* take a reference now to pin the lockres, drop it
1471 		 * when locks are added in the worker */
1472 		dlm_change_lockres_owner(dlm, res, dlm->node_num);
1473 	}
1474 	spin_unlock(&res->spinlock);
1475 
1476 	/* queue up work for dlm_mig_lockres_worker */
1477 	dlm_grab(dlm);  /* get an extra ref for the work item */
1478 	memcpy(buf, msg->buf, be16_to_cpu(msg->data_len));  /* copy the whole message */
1479 	dlm_init_work_item(dlm, item, dlm_mig_lockres_worker, buf);
1480 	item->u.ml.lockres = res; /* already have a ref */
1481 	item->u.ml.real_master = real_master;
1482 	item->u.ml.extra_ref = extra_refs;
1483 	spin_lock(&dlm->work_lock);
1484 	list_add_tail(&item->list, &dlm->work_list);
1485 	spin_unlock(&dlm->work_lock);
1486 	queue_work(dlm->dlm_worker, &dlm->dispatched_work);
1487 
1488 leave:
1489 	/* One extra ref taken needs to be put here */
1490 	if (extra_refs)
1491 		dlm_lockres_put(res);
1492 
1493 	dlm_put(dlm);
1494 	if (ret < 0) {
1495 		if (buf)
1496 			kfree(buf);
1497 		if (item)
1498 			kfree(item);
1499 	}
1500 
1501 	mlog_exit(ret);
1502 	return ret;
1503 }
1504 
1505 
1506 static void dlm_mig_lockres_worker(struct dlm_work_item *item, void *data)
1507 {
1508 	struct dlm_ctxt *dlm;
1509 	struct dlm_migratable_lockres *mres;
1510 	int ret = 0;
1511 	struct dlm_lock_resource *res;
1512 	u8 real_master;
1513 	u8 extra_ref;
1514 
1515 	dlm = item->dlm;
1516 	mres = (struct dlm_migratable_lockres *)data;
1517 
1518 	res = item->u.ml.lockres;
1519 	real_master = item->u.ml.real_master;
1520 	extra_ref = item->u.ml.extra_ref;
1521 
1522 	if (real_master == DLM_LOCK_RES_OWNER_UNKNOWN) {
1523 		/* this case is super-rare. only occurs if
1524 		 * node death happens during migration. */
1525 again:
1526 		ret = dlm_lockres_master_requery(dlm, res, &real_master);
1527 		if (ret < 0) {
1528 			mlog(0, "dlm_lockres_master_requery ret=%d\n",
1529 				  ret);
1530 			goto again;
1531 		}
1532 		if (real_master == DLM_LOCK_RES_OWNER_UNKNOWN) {
1533 			mlog(0, "lockres %.*s not claimed.  "
1534 				   "this node will take it.\n",
1535 				   res->lockname.len, res->lockname.name);
1536 		} else {
1537 			spin_lock(&res->spinlock);
1538 			dlm_lockres_drop_inflight_ref(dlm, res);
1539 			spin_unlock(&res->spinlock);
1540 			mlog(0, "master needs to respond to sender "
1541 				  "that node %u still owns %.*s\n",
1542 				  real_master, res->lockname.len,
1543 				  res->lockname.name);
1544 			/* cannot touch this lockres */
1545 			goto leave;
1546 		}
1547 	}
1548 
1549 	ret = dlm_process_recovery_data(dlm, res, mres);
1550 	if (ret < 0)
1551 		mlog(0, "dlm_process_recovery_data returned  %d\n", ret);
1552 	else
1553 		mlog(0, "dlm_process_recovery_data succeeded\n");
1554 
1555 	if ((mres->flags & (DLM_MRES_MIGRATION|DLM_MRES_ALL_DONE)) ==
1556 	                   (DLM_MRES_MIGRATION|DLM_MRES_ALL_DONE)) {
1557 		ret = dlm_finish_migration(dlm, res, mres->master);
1558 		if (ret < 0)
1559 			mlog_errno(ret);
1560 	}
1561 
1562 leave:
1563 	/* See comment in dlm_mig_lockres_handler() */
1564 	if (res) {
1565 		if (extra_ref)
1566 			dlm_lockres_put(res);
1567 		dlm_lockres_put(res);
1568 	}
1569 	kfree(data);
1570 	mlog_exit(ret);
1571 }
1572 
1573 
1574 
1575 static int dlm_lockres_master_requery(struct dlm_ctxt *dlm,
1576 				      struct dlm_lock_resource *res,
1577 				      u8 *real_master)
1578 {
1579 	struct dlm_node_iter iter;
1580 	int nodenum;
1581 	int ret = 0;
1582 
1583 	*real_master = DLM_LOCK_RES_OWNER_UNKNOWN;
1584 
1585 	/* we only reach here if one of the two nodes in a
1586 	 * migration died while the migration was in progress.
1587 	 * at this point we need to requery the master.  we
1588 	 * know that the new_master got as far as creating
1589 	 * an mle on at least one node, but we do not know
1590 	 * if any nodes had actually cleared the mle and set
1591 	 * the master to the new_master.  the old master
1592 	 * is supposed to set the owner to UNKNOWN in the
1593 	 * event of a new_master death, so the only possible
1594 	 * responses that we can get from nodes here are
1595 	 * that the master is new_master, or that the master
1596 	 * is UNKNOWN.
1597 	 * if all nodes come back with UNKNOWN then we know
1598 	 * the lock needs remastering here.
1599 	 * if any node comes back with a valid master, check
1600 	 * to see if that master is the one that we are
1601 	 * recovering.  if so, then the new_master died and
1602 	 * we need to remaster this lock.  if not, then the
1603 	 * new_master survived and that node will respond to
1604 	 * other nodes about the owner.
1605 	 * if there is an owner, this node needs to dump this
1606 	 * lockres and alert the sender that this lockres
1607 	 * was rejected. */
1608 	spin_lock(&dlm->spinlock);
1609 	dlm_node_iter_init(dlm->domain_map, &iter);
1610 	spin_unlock(&dlm->spinlock);
1611 
1612 	while ((nodenum = dlm_node_iter_next(&iter)) >= 0) {
1613 		/* do not send to self */
1614 		if (nodenum == dlm->node_num)
1615 			continue;
1616 		ret = dlm_do_master_requery(dlm, res, nodenum, real_master);
1617 		if (ret < 0) {
1618 			mlog_errno(ret);
1619 			if (!dlm_is_host_down(ret))
1620 				BUG();
1621 			/* host is down, so answer for that node would be
1622 			 * DLM_LOCK_RES_OWNER_UNKNOWN.  continue. */
1623 		}
1624 		if (*real_master != DLM_LOCK_RES_OWNER_UNKNOWN) {
1625 			mlog(0, "lock master is %u\n", *real_master);
1626 			break;
1627 		}
1628 	}
1629 	return ret;
1630 }
1631 
1632 
1633 int dlm_do_master_requery(struct dlm_ctxt *dlm, struct dlm_lock_resource *res,
1634 			  u8 nodenum, u8 *real_master)
1635 {
1636 	int ret = -EINVAL;
1637 	struct dlm_master_requery req;
1638 	int status = DLM_LOCK_RES_OWNER_UNKNOWN;
1639 
1640 	memset(&req, 0, sizeof(req));
1641 	req.node_idx = dlm->node_num;
1642 	req.namelen = res->lockname.len;
1643 	memcpy(req.name, res->lockname.name, res->lockname.len);
1644 
1645 	ret = o2net_send_message(DLM_MASTER_REQUERY_MSG, dlm->key,
1646 				 &req, sizeof(req), nodenum, &status);
1647 	/* XXX: negative status not handled properly here. */
1648 	if (ret < 0)
1649 		mlog(ML_ERROR, "Error %d when sending message %u (key "
1650 		     "0x%x) to node %u\n", ret, DLM_MASTER_REQUERY_MSG,
1651 		     dlm->key, nodenum);
1652 	else {
1653 		BUG_ON(status < 0);
1654 		BUG_ON(status > DLM_LOCK_RES_OWNER_UNKNOWN);
1655 		*real_master = (u8) (status & 0xff);
1656 		mlog(0, "node %u responded to master requery with %u\n",
1657 			  nodenum, *real_master);
1658 		ret = 0;
1659 	}
1660 	return ret;
1661 }
1662 
1663 
1664 /* this function cannot error, so unless the sending
1665  * or receiving of the message failed, the owner can
1666  * be trusted */
1667 int dlm_master_requery_handler(struct o2net_msg *msg, u32 len, void *data,
1668 			       void **ret_data)
1669 {
1670 	struct dlm_ctxt *dlm = data;
1671 	struct dlm_master_requery *req = (struct dlm_master_requery *)msg->buf;
1672 	struct dlm_lock_resource *res = NULL;
1673 	unsigned int hash;
1674 	int master = DLM_LOCK_RES_OWNER_UNKNOWN;
1675 	u32 flags = DLM_ASSERT_MASTER_REQUERY;
1676 
1677 	if (!dlm_grab(dlm)) {
1678 		/* since the domain has gone away on this
1679 		 * node, the proper response is UNKNOWN */
1680 		return master;
1681 	}
1682 
1683 	hash = dlm_lockid_hash(req->name, req->namelen);
1684 
1685 	spin_lock(&dlm->spinlock);
1686 	res = __dlm_lookup_lockres(dlm, req->name, req->namelen, hash);
1687 	if (res) {
1688 		spin_lock(&res->spinlock);
1689 		master = res->owner;
1690 		if (master == dlm->node_num) {
1691 			int ret = dlm_dispatch_assert_master(dlm, res,
1692 							     0, 0, flags);
1693 			if (ret < 0) {
1694 				mlog_errno(-ENOMEM);
1695 				/* retry!? */
1696 				BUG();
1697 			}
1698 		} else /* put.. incase we are not the master */
1699 			dlm_lockres_put(res);
1700 		spin_unlock(&res->spinlock);
1701 	}
1702 	spin_unlock(&dlm->spinlock);
1703 
1704 	dlm_put(dlm);
1705 	return master;
1706 }
1707 
1708 static inline struct list_head *
1709 dlm_list_num_to_pointer(struct dlm_lock_resource *res, int list_num)
1710 {
1711 	struct list_head *ret;
1712 	BUG_ON(list_num < 0);
1713 	BUG_ON(list_num > 2);
1714 	ret = &(res->granted);
1715 	ret += list_num;
1716 	return ret;
1717 }
1718 /* TODO: do ast flush business
1719  * TODO: do MIGRATING and RECOVERING spinning
1720  */
1721 
1722 /*
1723 * NOTE about in-flight requests during migration:
1724 *
1725 * Before attempting the migrate, the master has marked the lockres as
1726 * MIGRATING and then flushed all of its pending ASTS.  So any in-flight
1727 * requests either got queued before the MIGRATING flag got set, in which
1728 * case the lock data will reflect the change and a return message is on
1729 * the way, or the request failed to get in before MIGRATING got set.  In
1730 * this case, the caller will be told to spin and wait for the MIGRATING
1731 * flag to be dropped, then recheck the master.
1732 * This holds true for the convert, cancel and unlock cases, and since lvb
1733 * updates are tied to these same messages, it applies to lvb updates as
1734 * well.  For the lock case, there is no way a lock can be on the master
1735 * queue and not be on the secondary queue since the lock is always added
1736 * locally first.  This means that the new target node will never be sent
1737 * a lock that he doesn't already have on the list.
1738 * In total, this means that the local lock is correct and should not be
1739 * updated to match the one sent by the master.  Any messages sent back
1740 * from the master before the MIGRATING flag will bring the lock properly
1741 * up-to-date, and the change will be ordered properly for the waiter.
1742 * We will *not* attempt to modify the lock underneath the waiter.
1743 */
1744 
1745 static int dlm_process_recovery_data(struct dlm_ctxt *dlm,
1746 				     struct dlm_lock_resource *res,
1747 				     struct dlm_migratable_lockres *mres)
1748 {
1749 	struct dlm_migratable_lock *ml;
1750 	struct list_head *queue;
1751 	struct list_head *tmpq = NULL;
1752 	struct dlm_lock *newlock = NULL;
1753 	struct dlm_lockstatus *lksb = NULL;
1754 	int ret = 0;
1755 	int i, j, bad;
1756 	struct dlm_lock *lock = NULL;
1757 	u8 from = O2NM_MAX_NODES;
1758 	unsigned int added = 0;
1759 	__be64 c;
1760 
1761 	mlog(0, "running %d locks for this lockres\n", mres->num_locks);
1762 	for (i=0; i<mres->num_locks; i++) {
1763 		ml = &(mres->ml[i]);
1764 
1765 		if (dlm_is_dummy_lock(dlm, ml, &from)) {
1766 			/* placeholder, just need to set the refmap bit */
1767 			BUG_ON(mres->num_locks != 1);
1768 			mlog(0, "%s:%.*s: dummy lock for %u\n",
1769 			     dlm->name, mres->lockname_len, mres->lockname,
1770 			     from);
1771 			spin_lock(&res->spinlock);
1772 			dlm_lockres_set_refmap_bit(from, res);
1773 			spin_unlock(&res->spinlock);
1774 			added++;
1775 			break;
1776 		}
1777 		BUG_ON(ml->highest_blocked != LKM_IVMODE);
1778 		newlock = NULL;
1779 		lksb = NULL;
1780 
1781 		queue = dlm_list_num_to_pointer(res, ml->list);
1782 		tmpq = NULL;
1783 
1784 		/* if the lock is for the local node it needs to
1785 		 * be moved to the proper location within the queue.
1786 		 * do not allocate a new lock structure. */
1787 		if (ml->node == dlm->node_num) {
1788 			/* MIGRATION ONLY! */
1789 			BUG_ON(!(mres->flags & DLM_MRES_MIGRATION));
1790 
1791 			spin_lock(&res->spinlock);
1792 			for (j = DLM_GRANTED_LIST; j <= DLM_BLOCKED_LIST; j++) {
1793 				tmpq = dlm_list_idx_to_ptr(res, j);
1794 				list_for_each_entry(lock, tmpq, list) {
1795 					if (lock->ml.cookie != ml->cookie)
1796 						lock = NULL;
1797 					else
1798 						break;
1799 				}
1800 				if (lock)
1801 					break;
1802 			}
1803 
1804 			/* lock is always created locally first, and
1805 			 * destroyed locally last.  it must be on the list */
1806 			if (!lock) {
1807 				c = ml->cookie;
1808 				mlog(ML_ERROR, "Could not find local lock "
1809 					       "with cookie %u:%llu, node %u, "
1810 					       "list %u, flags 0x%x, type %d, "
1811 					       "conv %d, highest blocked %d\n",
1812 				     dlm_get_lock_cookie_node(be64_to_cpu(c)),
1813 				     dlm_get_lock_cookie_seq(be64_to_cpu(c)),
1814 				     ml->node, ml->list, ml->flags, ml->type,
1815 				     ml->convert_type, ml->highest_blocked);
1816 				__dlm_print_one_lock_resource(res);
1817 				BUG();
1818 			}
1819 
1820 			if (lock->ml.node != ml->node) {
1821 				c = lock->ml.cookie;
1822 				mlog(ML_ERROR, "Mismatched node# in lock "
1823 				     "cookie %u:%llu, name %.*s, node %u\n",
1824 				     dlm_get_lock_cookie_node(be64_to_cpu(c)),
1825 				     dlm_get_lock_cookie_seq(be64_to_cpu(c)),
1826 				     res->lockname.len, res->lockname.name,
1827 				     lock->ml.node);
1828 				c = ml->cookie;
1829 				mlog(ML_ERROR, "Migrate lock cookie %u:%llu, "
1830 				     "node %u, list %u, flags 0x%x, type %d, "
1831 				     "conv %d, highest blocked %d\n",
1832 				     dlm_get_lock_cookie_node(be64_to_cpu(c)),
1833 				     dlm_get_lock_cookie_seq(be64_to_cpu(c)),
1834 				     ml->node, ml->list, ml->flags, ml->type,
1835 				     ml->convert_type, ml->highest_blocked);
1836 				__dlm_print_one_lock_resource(res);
1837 				BUG();
1838 			}
1839 
1840 			if (tmpq != queue) {
1841 				c = ml->cookie;
1842 				mlog(0, "Lock cookie %u:%llu was on list %u "
1843 				     "instead of list %u for %.*s\n",
1844 				     dlm_get_lock_cookie_node(be64_to_cpu(c)),
1845 				     dlm_get_lock_cookie_seq(be64_to_cpu(c)),
1846 				     j, ml->list, res->lockname.len,
1847 				     res->lockname.name);
1848 				__dlm_print_one_lock_resource(res);
1849 				spin_unlock(&res->spinlock);
1850 				continue;
1851 			}
1852 
1853 			/* see NOTE above about why we do not update
1854 			 * to match the master here */
1855 
1856 			/* move the lock to its proper place */
1857 			/* do not alter lock refcount.  switching lists. */
1858 			list_move_tail(&lock->list, queue);
1859 			spin_unlock(&res->spinlock);
1860 			added++;
1861 
1862 			mlog(0, "just reordered a local lock!\n");
1863 			continue;
1864 		}
1865 
1866 		/* lock is for another node. */
1867 		newlock = dlm_new_lock(ml->type, ml->node,
1868 				       be64_to_cpu(ml->cookie), NULL);
1869 		if (!newlock) {
1870 			ret = -ENOMEM;
1871 			goto leave;
1872 		}
1873 		lksb = newlock->lksb;
1874 		dlm_lock_attach_lockres(newlock, res);
1875 
1876 		if (ml->convert_type != LKM_IVMODE) {
1877 			BUG_ON(queue != &res->converting);
1878 			newlock->ml.convert_type = ml->convert_type;
1879 		}
1880 		lksb->flags |= (ml->flags &
1881 				(DLM_LKSB_PUT_LVB|DLM_LKSB_GET_LVB));
1882 
1883 		if (ml->type == LKM_NLMODE)
1884 			goto skip_lvb;
1885 
1886 		if (!dlm_lvb_is_empty(mres->lvb)) {
1887 			if (lksb->flags & DLM_LKSB_PUT_LVB) {
1888 				/* other node was trying to update
1889 				 * lvb when node died.  recreate the
1890 				 * lksb with the updated lvb. */
1891 				memcpy(lksb->lvb, mres->lvb, DLM_LVB_LEN);
1892 				/* the lock resource lvb update must happen
1893 				 * NOW, before the spinlock is dropped.
1894 				 * we no longer wait for the AST to update
1895 				 * the lvb. */
1896 				memcpy(res->lvb, mres->lvb, DLM_LVB_LEN);
1897 			} else {
1898 				/* otherwise, the node is sending its
1899 				 * most recent valid lvb info */
1900 				BUG_ON(ml->type != LKM_EXMODE &&
1901 				       ml->type != LKM_PRMODE);
1902 				if (!dlm_lvb_is_empty(res->lvb) &&
1903  				    (ml->type == LKM_EXMODE ||
1904  				     memcmp(res->lvb, mres->lvb, DLM_LVB_LEN))) {
1905  					int i;
1906  					mlog(ML_ERROR, "%s:%.*s: received bad "
1907  					     "lvb! type=%d\n", dlm->name,
1908  					     res->lockname.len,
1909  					     res->lockname.name, ml->type);
1910  					printk("lockres lvb=[");
1911  					for (i=0; i<DLM_LVB_LEN; i++)
1912  						printk("%02x", res->lvb[i]);
1913  					printk("]\nmigrated lvb=[");
1914  					for (i=0; i<DLM_LVB_LEN; i++)
1915  						printk("%02x", mres->lvb[i]);
1916  					printk("]\n");
1917  					dlm_print_one_lock_resource(res);
1918  					BUG();
1919 				}
1920 				memcpy(res->lvb, mres->lvb, DLM_LVB_LEN);
1921 			}
1922 		}
1923 skip_lvb:
1924 
1925 		/* NOTE:
1926 		 * wrt lock queue ordering and recovery:
1927 		 *    1. order of locks on granted queue is
1928 		 *       meaningless.
1929 		 *    2. order of locks on converting queue is
1930 		 *       LOST with the node death.  sorry charlie.
1931 		 *    3. order of locks on the blocked queue is
1932 		 *       also LOST.
1933 		 * order of locks does not affect integrity, it
1934 		 * just means that a lock request may get pushed
1935 		 * back in line as a result of the node death.
1936 		 * also note that for a given node the lock order
1937 		 * for its secondary queue locks is preserved
1938 		 * relative to each other, but clearly *not*
1939 		 * preserved relative to locks from other nodes.
1940 		 */
1941 		bad = 0;
1942 		spin_lock(&res->spinlock);
1943 		list_for_each_entry(lock, queue, list) {
1944 			if (lock->ml.cookie == ml->cookie) {
1945 				c = lock->ml.cookie;
1946 				mlog(ML_ERROR, "%s:%.*s: %u:%llu: lock already "
1947 				     "exists on this lockres!\n", dlm->name,
1948 				     res->lockname.len, res->lockname.name,
1949 				     dlm_get_lock_cookie_node(be64_to_cpu(c)),
1950 				     dlm_get_lock_cookie_seq(be64_to_cpu(c)));
1951 
1952 				mlog(ML_NOTICE, "sent lock: type=%d, conv=%d, "
1953 				     "node=%u, cookie=%u:%llu, queue=%d\n",
1954 	      			     ml->type, ml->convert_type, ml->node,
1955 				     dlm_get_lock_cookie_node(be64_to_cpu(ml->cookie)),
1956 				     dlm_get_lock_cookie_seq(be64_to_cpu(ml->cookie)),
1957 				     ml->list);
1958 
1959 				__dlm_print_one_lock_resource(res);
1960 				bad = 1;
1961 				break;
1962 			}
1963 		}
1964 		if (!bad) {
1965 			dlm_lock_get(newlock);
1966 			list_add_tail(&newlock->list, queue);
1967 			mlog(0, "%s:%.*s: added lock for node %u, "
1968 			     "setting refmap bit\n", dlm->name,
1969 			     res->lockname.len, res->lockname.name, ml->node);
1970 			dlm_lockres_set_refmap_bit(ml->node, res);
1971 			added++;
1972 		}
1973 		spin_unlock(&res->spinlock);
1974 	}
1975 	mlog(0, "done running all the locks\n");
1976 
1977 leave:
1978 	/* balance the ref taken when the work was queued */
1979 	spin_lock(&res->spinlock);
1980 	dlm_lockres_drop_inflight_ref(dlm, res);
1981 	spin_unlock(&res->spinlock);
1982 
1983 	if (ret < 0) {
1984 		mlog_errno(ret);
1985 		if (newlock)
1986 			dlm_lock_put(newlock);
1987 	}
1988 
1989 	mlog_exit(ret);
1990 	return ret;
1991 }
1992 
1993 void dlm_move_lockres_to_recovery_list(struct dlm_ctxt *dlm,
1994 				       struct dlm_lock_resource *res)
1995 {
1996 	int i;
1997 	struct list_head *queue;
1998 	struct dlm_lock *lock, *next;
1999 
2000 	assert_spin_locked(&dlm->spinlock);
2001 	assert_spin_locked(&res->spinlock);
2002 	res->state |= DLM_LOCK_RES_RECOVERING;
2003 	if (!list_empty(&res->recovering)) {
2004 		mlog(0,
2005 		     "Recovering res %s:%.*s, is already on recovery list!\n",
2006 		     dlm->name, res->lockname.len, res->lockname.name);
2007 		list_del_init(&res->recovering);
2008 		dlm_lockres_put(res);
2009 	}
2010 	/* We need to hold a reference while on the recovery list */
2011 	dlm_lockres_get(res);
2012 	list_add_tail(&res->recovering, &dlm->reco.resources);
2013 
2014 	/* find any pending locks and put them back on proper list */
2015 	for (i=DLM_BLOCKED_LIST; i>=DLM_GRANTED_LIST; i--) {
2016 		queue = dlm_list_idx_to_ptr(res, i);
2017 		list_for_each_entry_safe(lock, next, queue, list) {
2018 			dlm_lock_get(lock);
2019 			if (lock->convert_pending) {
2020 				/* move converting lock back to granted */
2021 				BUG_ON(i != DLM_CONVERTING_LIST);
2022 				mlog(0, "node died with convert pending "
2023 				     "on %.*s. move back to granted list.\n",
2024 				     res->lockname.len, res->lockname.name);
2025 				dlm_revert_pending_convert(res, lock);
2026 				lock->convert_pending = 0;
2027 			} else if (lock->lock_pending) {
2028 				/* remove pending lock requests completely */
2029 				BUG_ON(i != DLM_BLOCKED_LIST);
2030 				mlog(0, "node died with lock pending "
2031 				     "on %.*s. remove from blocked list and skip.\n",
2032 				     res->lockname.len, res->lockname.name);
2033 				/* lock will be floating until ref in
2034 				 * dlmlock_remote is freed after the network
2035 				 * call returns.  ok for it to not be on any
2036 				 * list since no ast can be called
2037 				 * (the master is dead). */
2038 				dlm_revert_pending_lock(res, lock);
2039 				lock->lock_pending = 0;
2040 			} else if (lock->unlock_pending) {
2041 				/* if an unlock was in progress, treat as
2042 				 * if this had completed successfully
2043 				 * before sending this lock state to the
2044 				 * new master.  note that the dlm_unlock
2045 				 * call is still responsible for calling
2046 				 * the unlockast.  that will happen after
2047 				 * the network call times out.  for now,
2048 				 * just move lists to prepare the new
2049 				 * recovery master.  */
2050 				BUG_ON(i != DLM_GRANTED_LIST);
2051 				mlog(0, "node died with unlock pending "
2052 				     "on %.*s. remove from blocked list and skip.\n",
2053 				     res->lockname.len, res->lockname.name);
2054 				dlm_commit_pending_unlock(res, lock);
2055 				lock->unlock_pending = 0;
2056 			} else if (lock->cancel_pending) {
2057 				/* if a cancel was in progress, treat as
2058 				 * if this had completed successfully
2059 				 * before sending this lock state to the
2060 				 * new master */
2061 				BUG_ON(i != DLM_CONVERTING_LIST);
2062 				mlog(0, "node died with cancel pending "
2063 				     "on %.*s. move back to granted list.\n",
2064 				     res->lockname.len, res->lockname.name);
2065 				dlm_commit_pending_cancel(res, lock);
2066 				lock->cancel_pending = 0;
2067 			}
2068 			dlm_lock_put(lock);
2069 		}
2070 	}
2071 }
2072 
2073 
2074 
2075 /* removes all recovered locks from the recovery list.
2076  * sets the res->owner to the new master.
2077  * unsets the RECOVERY flag and wakes waiters. */
2078 static void dlm_finish_local_lockres_recovery(struct dlm_ctxt *dlm,
2079 					      u8 dead_node, u8 new_master)
2080 {
2081 	int i;
2082 	struct hlist_node *hash_iter;
2083 	struct hlist_head *bucket;
2084 	struct dlm_lock_resource *res, *next;
2085 
2086 	mlog_entry_void();
2087 
2088 	assert_spin_locked(&dlm->spinlock);
2089 
2090 	list_for_each_entry_safe(res, next, &dlm->reco.resources, recovering) {
2091 		if (res->owner == dead_node) {
2092 			list_del_init(&res->recovering);
2093 			spin_lock(&res->spinlock);
2094 			/* new_master has our reference from
2095 			 * the lock state sent during recovery */
2096 			dlm_change_lockres_owner(dlm, res, new_master);
2097 			res->state &= ~DLM_LOCK_RES_RECOVERING;
2098 			if (__dlm_lockres_has_locks(res))
2099 				__dlm_dirty_lockres(dlm, res);
2100 			spin_unlock(&res->spinlock);
2101 			wake_up(&res->wq);
2102 			dlm_lockres_put(res);
2103 		}
2104 	}
2105 
2106 	/* this will become unnecessary eventually, but
2107 	 * for now we need to run the whole hash, clear
2108 	 * the RECOVERING state and set the owner
2109 	 * if necessary */
2110 	for (i = 0; i < DLM_HASH_BUCKETS; i++) {
2111 		bucket = dlm_lockres_hash(dlm, i);
2112 		hlist_for_each_entry(res, hash_iter, bucket, hash_node) {
2113 			if (res->state & DLM_LOCK_RES_RECOVERING) {
2114 				if (res->owner == dead_node) {
2115 					mlog(0, "(this=%u) res %.*s owner=%u "
2116 					     "was not on recovering list, but "
2117 					     "clearing state anyway\n",
2118 					     dlm->node_num, res->lockname.len,
2119 					     res->lockname.name, new_master);
2120 				} else if (res->owner == dlm->node_num) {
2121 					mlog(0, "(this=%u) res %.*s owner=%u "
2122 					     "was not on recovering list, "
2123 					     "owner is THIS node, clearing\n",
2124 					     dlm->node_num, res->lockname.len,
2125 					     res->lockname.name, new_master);
2126 				} else
2127 					continue;
2128 
2129 				if (!list_empty(&res->recovering)) {
2130 					mlog(0, "%s:%.*s: lockres was "
2131 					     "marked RECOVERING, owner=%u\n",
2132 					     dlm->name, res->lockname.len,
2133 					     res->lockname.name, res->owner);
2134 					list_del_init(&res->recovering);
2135 					dlm_lockres_put(res);
2136 				}
2137 				spin_lock(&res->spinlock);
2138 				/* new_master has our reference from
2139 				 * the lock state sent during recovery */
2140 				dlm_change_lockres_owner(dlm, res, new_master);
2141 				res->state &= ~DLM_LOCK_RES_RECOVERING;
2142 				if (__dlm_lockres_has_locks(res))
2143 					__dlm_dirty_lockres(dlm, res);
2144 				spin_unlock(&res->spinlock);
2145 				wake_up(&res->wq);
2146 			}
2147 		}
2148 	}
2149 }
2150 
2151 static inline int dlm_lvb_needs_invalidation(struct dlm_lock *lock, int local)
2152 {
2153 	if (local) {
2154 		if (lock->ml.type != LKM_EXMODE &&
2155 		    lock->ml.type != LKM_PRMODE)
2156 			return 1;
2157 	} else if (lock->ml.type == LKM_EXMODE)
2158 		return 1;
2159 	return 0;
2160 }
2161 
2162 static void dlm_revalidate_lvb(struct dlm_ctxt *dlm,
2163 			       struct dlm_lock_resource *res, u8 dead_node)
2164 {
2165 	struct list_head *queue;
2166 	struct dlm_lock *lock;
2167 	int blank_lvb = 0, local = 0;
2168 	int i;
2169 	u8 search_node;
2170 
2171 	assert_spin_locked(&dlm->spinlock);
2172 	assert_spin_locked(&res->spinlock);
2173 
2174 	if (res->owner == dlm->node_num)
2175 		/* if this node owned the lockres, and if the dead node
2176 		 * had an EX when he died, blank out the lvb */
2177 		search_node = dead_node;
2178 	else {
2179 		/* if this is a secondary lockres, and we had no EX or PR
2180 		 * locks granted, we can no longer trust the lvb */
2181 		search_node = dlm->node_num;
2182 		local = 1;  /* check local state for valid lvb */
2183 	}
2184 
2185 	for (i=DLM_GRANTED_LIST; i<=DLM_CONVERTING_LIST; i++) {
2186 		queue = dlm_list_idx_to_ptr(res, i);
2187 		list_for_each_entry(lock, queue, list) {
2188 			if (lock->ml.node == search_node) {
2189 				if (dlm_lvb_needs_invalidation(lock, local)) {
2190 					/* zero the lksb lvb and lockres lvb */
2191 					blank_lvb = 1;
2192 					memset(lock->lksb->lvb, 0, DLM_LVB_LEN);
2193 				}
2194 			}
2195 		}
2196 	}
2197 
2198 	if (blank_lvb) {
2199 		mlog(0, "clearing %.*s lvb, dead node %u had EX\n",
2200 		     res->lockname.len, res->lockname.name, dead_node);
2201 		memset(res->lvb, 0, DLM_LVB_LEN);
2202 	}
2203 }
2204 
2205 static void dlm_free_dead_locks(struct dlm_ctxt *dlm,
2206 				struct dlm_lock_resource *res, u8 dead_node)
2207 {
2208 	struct dlm_lock *lock, *next;
2209 	unsigned int freed = 0;
2210 
2211 	/* this node is the lockres master:
2212 	 * 1) remove any stale locks for the dead node
2213 	 * 2) if the dead node had an EX when he died, blank out the lvb
2214 	 */
2215 	assert_spin_locked(&dlm->spinlock);
2216 	assert_spin_locked(&res->spinlock);
2217 
2218 	/* We do two dlm_lock_put(). One for removing from list and the other is
2219 	 * to force the DLM_UNLOCK_FREE_LOCK action so as to free the locks */
2220 
2221 	/* TODO: check pending_asts, pending_basts here */
2222 	list_for_each_entry_safe(lock, next, &res->granted, list) {
2223 		if (lock->ml.node == dead_node) {
2224 			list_del_init(&lock->list);
2225 			dlm_lock_put(lock);
2226 			/* Can't schedule DLM_UNLOCK_FREE_LOCK - do manually */
2227 			dlm_lock_put(lock);
2228 			freed++;
2229 		}
2230 	}
2231 	list_for_each_entry_safe(lock, next, &res->converting, list) {
2232 		if (lock->ml.node == dead_node) {
2233 			list_del_init(&lock->list);
2234 			dlm_lock_put(lock);
2235 			/* Can't schedule DLM_UNLOCK_FREE_LOCK - do manually */
2236 			dlm_lock_put(lock);
2237 			freed++;
2238 		}
2239 	}
2240 	list_for_each_entry_safe(lock, next, &res->blocked, list) {
2241 		if (lock->ml.node == dead_node) {
2242 			list_del_init(&lock->list);
2243 			dlm_lock_put(lock);
2244 			/* Can't schedule DLM_UNLOCK_FREE_LOCK - do manually */
2245 			dlm_lock_put(lock);
2246 			freed++;
2247 		}
2248 	}
2249 
2250 	if (freed) {
2251 		mlog(0, "%s:%.*s: freed %u locks for dead node %u, "
2252 		     "dropping ref from lockres\n", dlm->name,
2253 		     res->lockname.len, res->lockname.name, freed, dead_node);
2254 		if(!test_bit(dead_node, res->refmap)) {
2255 			mlog(ML_ERROR, "%s:%.*s: freed %u locks for dead node %u, "
2256 			     "but ref was not set\n", dlm->name,
2257 			     res->lockname.len, res->lockname.name, freed, dead_node);
2258 			__dlm_print_one_lock_resource(res);
2259 		}
2260 		dlm_lockres_clear_refmap_bit(dead_node, res);
2261 	} else if (test_bit(dead_node, res->refmap)) {
2262 		mlog(0, "%s:%.*s: dead node %u had a ref, but had "
2263 		     "no locks and had not purged before dying\n", dlm->name,
2264 		     res->lockname.len, res->lockname.name, dead_node);
2265 		dlm_lockres_clear_refmap_bit(dead_node, res);
2266 	}
2267 
2268 	/* do not kick thread yet */
2269 	__dlm_dirty_lockres(dlm, res);
2270 }
2271 
2272 /* if this node is the recovery master, and there are no
2273  * locks for a given lockres owned by this node that are in
2274  * either PR or EX mode, zero out the lvb before requesting.
2275  *
2276  */
2277 
2278 
2279 static void dlm_do_local_recovery_cleanup(struct dlm_ctxt *dlm, u8 dead_node)
2280 {
2281 	struct hlist_node *iter;
2282 	struct dlm_lock_resource *res;
2283 	int i;
2284 	struct hlist_head *bucket;
2285 	struct dlm_lock *lock;
2286 
2287 
2288 	/* purge any stale mles */
2289 	dlm_clean_master_list(dlm, dead_node);
2290 
2291 	/*
2292 	 * now clean up all lock resources.  there are two rules:
2293 	 *
2294 	 * 1) if the dead node was the master, move the lockres
2295 	 *    to the recovering list.  set the RECOVERING flag.
2296 	 *    this lockres needs to be cleaned up before it can
2297 	 *    be used further.
2298 	 *
2299 	 * 2) if this node was the master, remove all locks from
2300 	 *    each of the lockres queues that were owned by the
2301 	 *    dead node.  once recovery finishes, the dlm thread
2302 	 *    can be kicked again to see if any ASTs or BASTs
2303 	 *    need to be fired as a result.
2304 	 */
2305 	for (i = 0; i < DLM_HASH_BUCKETS; i++) {
2306 		bucket = dlm_lockres_hash(dlm, i);
2307 		hlist_for_each_entry(res, iter, bucket, hash_node) {
2308  			/* always prune any $RECOVERY entries for dead nodes,
2309  			 * otherwise hangs can occur during later recovery */
2310 			if (dlm_is_recovery_lock(res->lockname.name,
2311 						 res->lockname.len)) {
2312 				spin_lock(&res->spinlock);
2313 				list_for_each_entry(lock, &res->granted, list) {
2314 					if (lock->ml.node == dead_node) {
2315 						mlog(0, "AHA! there was "
2316 						     "a $RECOVERY lock for dead "
2317 						     "node %u (%s)!\n",
2318 						     dead_node, dlm->name);
2319 						list_del_init(&lock->list);
2320 						dlm_lock_put(lock);
2321 						break;
2322 					}
2323 				}
2324 				spin_unlock(&res->spinlock);
2325 				continue;
2326 			}
2327 			spin_lock(&res->spinlock);
2328 			/* zero the lvb if necessary */
2329 			dlm_revalidate_lvb(dlm, res, dead_node);
2330 			if (res->owner == dead_node) {
2331 				if (res->state & DLM_LOCK_RES_DROPPING_REF) {
2332 					mlog(ML_NOTICE, "Ignore %.*s for "
2333 					     "recovery as it is being freed\n",
2334 					     res->lockname.len,
2335 					     res->lockname.name);
2336 				} else
2337 					dlm_move_lockres_to_recovery_list(dlm,
2338 									  res);
2339 
2340 			} else if (res->owner == dlm->node_num) {
2341 				dlm_free_dead_locks(dlm, res, dead_node);
2342 				__dlm_lockres_calc_usage(dlm, res);
2343 			}
2344 			spin_unlock(&res->spinlock);
2345 		}
2346 	}
2347 
2348 }
2349 
2350 static void __dlm_hb_node_down(struct dlm_ctxt *dlm, int idx)
2351 {
2352 	assert_spin_locked(&dlm->spinlock);
2353 
2354 	if (dlm->reco.new_master == idx) {
2355 		mlog(0, "%s: recovery master %d just died\n",
2356 		     dlm->name, idx);
2357 		if (dlm->reco.state & DLM_RECO_STATE_FINALIZE) {
2358 			/* finalize1 was reached, so it is safe to clear
2359 			 * the new_master and dead_node.  that recovery
2360 			 * is complete. */
2361 			mlog(0, "%s: dead master %d had reached "
2362 			     "finalize1 state, clearing\n", dlm->name, idx);
2363 			dlm->reco.state &= ~DLM_RECO_STATE_FINALIZE;
2364 			__dlm_reset_recovery(dlm);
2365 		}
2366 	}
2367 
2368 	/* Clean up join state on node death. */
2369 	if (dlm->joining_node == idx) {
2370 		mlog(0, "Clearing join state for node %u\n", idx);
2371 		__dlm_set_joining_node(dlm, DLM_LOCK_RES_OWNER_UNKNOWN);
2372 	}
2373 
2374 	/* check to see if the node is already considered dead */
2375 	if (!test_bit(idx, dlm->live_nodes_map)) {
2376 		mlog(0, "for domain %s, node %d is already dead. "
2377 		     "another node likely did recovery already.\n",
2378 		     dlm->name, idx);
2379 		return;
2380 	}
2381 
2382 	/* check to see if we do not care about this node */
2383 	if (!test_bit(idx, dlm->domain_map)) {
2384 		/* This also catches the case that we get a node down
2385 		 * but haven't joined the domain yet. */
2386 		mlog(0, "node %u already removed from domain!\n", idx);
2387 		return;
2388 	}
2389 
2390 	clear_bit(idx, dlm->live_nodes_map);
2391 
2392 	/* make sure local cleanup occurs before the heartbeat events */
2393 	if (!test_bit(idx, dlm->recovery_map))
2394 		dlm_do_local_recovery_cleanup(dlm, idx);
2395 
2396 	/* notify anything attached to the heartbeat events */
2397 	dlm_hb_event_notify_attached(dlm, idx, 0);
2398 
2399 	mlog(0, "node %u being removed from domain map!\n", idx);
2400 	clear_bit(idx, dlm->domain_map);
2401 	/* wake up migration waiters if a node goes down.
2402 	 * perhaps later we can genericize this for other waiters. */
2403 	wake_up(&dlm->migration_wq);
2404 
2405 	if (test_bit(idx, dlm->recovery_map))
2406 		mlog(0, "domain %s, node %u already added "
2407 		     "to recovery map!\n", dlm->name, idx);
2408 	else
2409 		set_bit(idx, dlm->recovery_map);
2410 }
2411 
2412 void dlm_hb_node_down_cb(struct o2nm_node *node, int idx, void *data)
2413 {
2414 	struct dlm_ctxt *dlm = data;
2415 
2416 	if (!dlm_grab(dlm))
2417 		return;
2418 
2419 	/*
2420 	 * This will notify any dlm users that a node in our domain
2421 	 * went away without notifying us first.
2422 	 */
2423 	if (test_bit(idx, dlm->domain_map))
2424 		dlm_fire_domain_eviction_callbacks(dlm, idx);
2425 
2426 	spin_lock(&dlm->spinlock);
2427 	__dlm_hb_node_down(dlm, idx);
2428 	spin_unlock(&dlm->spinlock);
2429 
2430 	dlm_put(dlm);
2431 }
2432 
2433 void dlm_hb_node_up_cb(struct o2nm_node *node, int idx, void *data)
2434 {
2435 	struct dlm_ctxt *dlm = data;
2436 
2437 	if (!dlm_grab(dlm))
2438 		return;
2439 
2440 	spin_lock(&dlm->spinlock);
2441 	set_bit(idx, dlm->live_nodes_map);
2442 	/* do NOT notify mle attached to the heartbeat events.
2443 	 * new nodes are not interesting in mastery until joined. */
2444 	spin_unlock(&dlm->spinlock);
2445 
2446 	dlm_put(dlm);
2447 }
2448 
2449 static void dlm_reco_ast(void *astdata)
2450 {
2451 	struct dlm_ctxt *dlm = astdata;
2452 	mlog(0, "ast for recovery lock fired!, this=%u, dlm=%s\n",
2453 	     dlm->node_num, dlm->name);
2454 }
2455 static void dlm_reco_bast(void *astdata, int blocked_type)
2456 {
2457 	struct dlm_ctxt *dlm = astdata;
2458 	mlog(0, "bast for recovery lock fired!, this=%u, dlm=%s\n",
2459 	     dlm->node_num, dlm->name);
2460 }
2461 static void dlm_reco_unlock_ast(void *astdata, enum dlm_status st)
2462 {
2463 	mlog(0, "unlockast for recovery lock fired!\n");
2464 }
2465 
2466 /*
2467  * dlm_pick_recovery_master will continually attempt to use
2468  * dlmlock() on the special "$RECOVERY" lockres with the
2469  * LKM_NOQUEUE flag to get an EX.  every thread that enters
2470  * this function on each node racing to become the recovery
2471  * master will not stop attempting this until either:
2472  * a) this node gets the EX (and becomes the recovery master),
2473  * or b) dlm->reco.new_master gets set to some nodenum
2474  * != O2NM_INVALID_NODE_NUM (another node will do the reco).
2475  * so each time a recovery master is needed, the entire cluster
2476  * will sync at this point.  if the new master dies, that will
2477  * be detected in dlm_do_recovery */
2478 static int dlm_pick_recovery_master(struct dlm_ctxt *dlm)
2479 {
2480 	enum dlm_status ret;
2481 	struct dlm_lockstatus lksb;
2482 	int status = -EINVAL;
2483 
2484 	mlog(0, "starting recovery of %s at %lu, dead=%u, this=%u\n",
2485 	     dlm->name, jiffies, dlm->reco.dead_node, dlm->node_num);
2486 again:
2487 	memset(&lksb, 0, sizeof(lksb));
2488 
2489 	ret = dlmlock(dlm, LKM_EXMODE, &lksb, LKM_NOQUEUE|LKM_RECOVERY,
2490 		      DLM_RECOVERY_LOCK_NAME, DLM_RECOVERY_LOCK_NAME_LEN,
2491 		      dlm_reco_ast, dlm, dlm_reco_bast);
2492 
2493 	mlog(0, "%s: dlmlock($RECOVERY) returned %d, lksb=%d\n",
2494 	     dlm->name, ret, lksb.status);
2495 
2496 	if (ret == DLM_NORMAL) {
2497 		mlog(0, "dlm=%s dlmlock says I got it (this=%u)\n",
2498 		     dlm->name, dlm->node_num);
2499 
2500 		/* got the EX lock.  check to see if another node
2501 		 * just became the reco master */
2502 		if (dlm_reco_master_ready(dlm)) {
2503 			mlog(0, "%s: got reco EX lock, but %u will "
2504 			     "do the recovery\n", dlm->name,
2505 			     dlm->reco.new_master);
2506 			status = -EEXIST;
2507 		} else {
2508 			status = 0;
2509 
2510 			/* see if recovery was already finished elsewhere */
2511 			spin_lock(&dlm->spinlock);
2512 			if (dlm->reco.dead_node == O2NM_INVALID_NODE_NUM) {
2513 				status = -EINVAL;
2514 				mlog(0, "%s: got reco EX lock, but "
2515 				     "node got recovered already\n", dlm->name);
2516 				if (dlm->reco.new_master != O2NM_INVALID_NODE_NUM) {
2517 					mlog(ML_ERROR, "%s: new master is %u "
2518 					     "but no dead node!\n",
2519 					     dlm->name, dlm->reco.new_master);
2520 					BUG();
2521 				}
2522 			}
2523 			spin_unlock(&dlm->spinlock);
2524 		}
2525 
2526 		/* if this node has actually become the recovery master,
2527 		 * set the master and send the messages to begin recovery */
2528 		if (!status) {
2529 			mlog(0, "%s: dead=%u, this=%u, sending "
2530 			     "begin_reco now\n", dlm->name,
2531 			     dlm->reco.dead_node, dlm->node_num);
2532 			status = dlm_send_begin_reco_message(dlm,
2533 				      dlm->reco.dead_node);
2534 			/* this always succeeds */
2535 			BUG_ON(status);
2536 
2537 			/* set the new_master to this node */
2538 			spin_lock(&dlm->spinlock);
2539 			dlm_set_reco_master(dlm, dlm->node_num);
2540 			spin_unlock(&dlm->spinlock);
2541 		}
2542 
2543 		/* recovery lock is a special case.  ast will not get fired,
2544 		 * so just go ahead and unlock it. */
2545 		ret = dlmunlock(dlm, &lksb, 0, dlm_reco_unlock_ast, dlm);
2546 		if (ret == DLM_DENIED) {
2547 			mlog(0, "got DLM_DENIED, trying LKM_CANCEL\n");
2548 			ret = dlmunlock(dlm, &lksb, LKM_CANCEL, dlm_reco_unlock_ast, dlm);
2549 		}
2550 		if (ret != DLM_NORMAL) {
2551 			/* this would really suck. this could only happen
2552 			 * if there was a network error during the unlock
2553 			 * because of node death.  this means the unlock
2554 			 * is actually "done" and the lock structure is
2555 			 * even freed.  we can continue, but only
2556 			 * because this specific lock name is special. */
2557 			mlog(ML_ERROR, "dlmunlock returned %d\n", ret);
2558 		}
2559 	} else if (ret == DLM_NOTQUEUED) {
2560 		mlog(0, "dlm=%s dlmlock says another node got it (this=%u)\n",
2561 		     dlm->name, dlm->node_num);
2562 		/* another node is master. wait on
2563 		 * reco.new_master != O2NM_INVALID_NODE_NUM
2564 		 * for at most one second */
2565 		wait_event_timeout(dlm->dlm_reco_thread_wq,
2566 					 dlm_reco_master_ready(dlm),
2567 					 msecs_to_jiffies(1000));
2568 		if (!dlm_reco_master_ready(dlm)) {
2569 			mlog(0, "%s: reco master taking awhile\n",
2570 			     dlm->name);
2571 			goto again;
2572 		}
2573 		/* another node has informed this one that it is reco master */
2574 		mlog(0, "%s: reco master %u is ready to recover %u\n",
2575 		     dlm->name, dlm->reco.new_master, dlm->reco.dead_node);
2576 		status = -EEXIST;
2577 	} else if (ret == DLM_RECOVERING) {
2578 		mlog(0, "dlm=%s dlmlock says master node died (this=%u)\n",
2579 		     dlm->name, dlm->node_num);
2580 		goto again;
2581 	} else {
2582 		struct dlm_lock_resource *res;
2583 
2584 		/* dlmlock returned something other than NOTQUEUED or NORMAL */
2585 		mlog(ML_ERROR, "%s: got %s from dlmlock($RECOVERY), "
2586 		     "lksb.status=%s\n", dlm->name, dlm_errname(ret),
2587 		     dlm_errname(lksb.status));
2588 		res = dlm_lookup_lockres(dlm, DLM_RECOVERY_LOCK_NAME,
2589 					 DLM_RECOVERY_LOCK_NAME_LEN);
2590 		if (res) {
2591 			dlm_print_one_lock_resource(res);
2592 			dlm_lockres_put(res);
2593 		} else {
2594 			mlog(ML_ERROR, "recovery lock not found\n");
2595 		}
2596 		BUG();
2597 	}
2598 
2599 	return status;
2600 }
2601 
2602 static int dlm_send_begin_reco_message(struct dlm_ctxt *dlm, u8 dead_node)
2603 {
2604 	struct dlm_begin_reco br;
2605 	int ret = 0;
2606 	struct dlm_node_iter iter;
2607 	int nodenum;
2608 	int status;
2609 
2610 	mlog_entry("%u\n", dead_node);
2611 
2612 	mlog(0, "%s: dead node is %u\n", dlm->name, dead_node);
2613 
2614 	spin_lock(&dlm->spinlock);
2615 	dlm_node_iter_init(dlm->domain_map, &iter);
2616 	spin_unlock(&dlm->spinlock);
2617 
2618 	clear_bit(dead_node, iter.node_map);
2619 
2620 	memset(&br, 0, sizeof(br));
2621 	br.node_idx = dlm->node_num;
2622 	br.dead_node = dead_node;
2623 
2624 	while ((nodenum = dlm_node_iter_next(&iter)) >= 0) {
2625 		ret = 0;
2626 		if (nodenum == dead_node) {
2627 			mlog(0, "not sending begin reco to dead node "
2628 				  "%u\n", dead_node);
2629 			continue;
2630 		}
2631 		if (nodenum == dlm->node_num) {
2632 			mlog(0, "not sending begin reco to self\n");
2633 			continue;
2634 		}
2635 retry:
2636 		ret = -EINVAL;
2637 		mlog(0, "attempting to send begin reco msg to %d\n",
2638 			  nodenum);
2639 		ret = o2net_send_message(DLM_BEGIN_RECO_MSG, dlm->key,
2640 					 &br, sizeof(br), nodenum, &status);
2641 		/* negative status is handled ok by caller here */
2642 		if (ret >= 0)
2643 			ret = status;
2644 		if (dlm_is_host_down(ret)) {
2645 			/* node is down.  not involved in recovery
2646 			 * so just keep going */
2647 			mlog(ML_NOTICE, "%s: node %u was down when sending "
2648 			     "begin reco msg (%d)\n", dlm->name, nodenum, ret);
2649 			ret = 0;
2650 		}
2651 
2652 		/*
2653 		 * Prior to commit aad1b15310b9bcd59fa81ab8f2b1513b59553ea8,
2654 		 * dlm_begin_reco_handler() returned EAGAIN and not -EAGAIN.
2655 		 * We are handling both for compatibility reasons.
2656 		 */
2657 		if (ret == -EAGAIN || ret == EAGAIN) {
2658 			mlog(0, "%s: trying to start recovery of node "
2659 			     "%u, but node %u is waiting for last recovery "
2660 			     "to complete, backoff for a bit\n", dlm->name,
2661 			     dead_node, nodenum);
2662 			msleep(100);
2663 			goto retry;
2664 		}
2665 		if (ret < 0) {
2666 			struct dlm_lock_resource *res;
2667 
2668 			/* this is now a serious problem, possibly ENOMEM
2669 			 * in the network stack.  must retry */
2670 			mlog_errno(ret);
2671 			mlog(ML_ERROR, "begin reco of dlm %s to node %u "
2672 			     "returned %d\n", dlm->name, nodenum, ret);
2673 			res = dlm_lookup_lockres(dlm, DLM_RECOVERY_LOCK_NAME,
2674 						 DLM_RECOVERY_LOCK_NAME_LEN);
2675 			if (res) {
2676 				dlm_print_one_lock_resource(res);
2677 				dlm_lockres_put(res);
2678 			} else {
2679 				mlog(ML_ERROR, "recovery lock not found\n");
2680 			}
2681 			/* sleep for a bit in hopes that we can avoid
2682 			 * another ENOMEM */
2683 			msleep(100);
2684 			goto retry;
2685 		}
2686 	}
2687 
2688 	return ret;
2689 }
2690 
2691 int dlm_begin_reco_handler(struct o2net_msg *msg, u32 len, void *data,
2692 			   void **ret_data)
2693 {
2694 	struct dlm_ctxt *dlm = data;
2695 	struct dlm_begin_reco *br = (struct dlm_begin_reco *)msg->buf;
2696 
2697 	/* ok to return 0, domain has gone away */
2698 	if (!dlm_grab(dlm))
2699 		return 0;
2700 
2701 	spin_lock(&dlm->spinlock);
2702 	if (dlm->reco.state & DLM_RECO_STATE_FINALIZE) {
2703 		mlog(0, "%s: node %u wants to recover node %u (%u:%u) "
2704 		     "but this node is in finalize state, waiting on finalize2\n",
2705 		     dlm->name, br->node_idx, br->dead_node,
2706 		     dlm->reco.dead_node, dlm->reco.new_master);
2707 		spin_unlock(&dlm->spinlock);
2708 		return -EAGAIN;
2709 	}
2710 	spin_unlock(&dlm->spinlock);
2711 
2712 	mlog(0, "%s: node %u wants to recover node %u (%u:%u)\n",
2713 	     dlm->name, br->node_idx, br->dead_node,
2714 	     dlm->reco.dead_node, dlm->reco.new_master);
2715 
2716 	dlm_fire_domain_eviction_callbacks(dlm, br->dead_node);
2717 
2718 	spin_lock(&dlm->spinlock);
2719 	if (dlm->reco.new_master != O2NM_INVALID_NODE_NUM) {
2720 		if (test_bit(dlm->reco.new_master, dlm->recovery_map)) {
2721 			mlog(0, "%s: new_master %u died, changing "
2722 			     "to %u\n", dlm->name, dlm->reco.new_master,
2723 			     br->node_idx);
2724 		} else {
2725 			mlog(0, "%s: new_master %u NOT DEAD, changing "
2726 			     "to %u\n", dlm->name, dlm->reco.new_master,
2727 			     br->node_idx);
2728 			/* may not have seen the new master as dead yet */
2729 		}
2730 	}
2731 	if (dlm->reco.dead_node != O2NM_INVALID_NODE_NUM) {
2732 		mlog(ML_NOTICE, "%s: dead_node previously set to %u, "
2733 		     "node %u changing it to %u\n", dlm->name,
2734 		     dlm->reco.dead_node, br->node_idx, br->dead_node);
2735 	}
2736 	dlm_set_reco_master(dlm, br->node_idx);
2737 	dlm_set_reco_dead_node(dlm, br->dead_node);
2738 	if (!test_bit(br->dead_node, dlm->recovery_map)) {
2739 		mlog(0, "recovery master %u sees %u as dead, but this "
2740 		     "node has not yet.  marking %u as dead\n",
2741 		     br->node_idx, br->dead_node, br->dead_node);
2742 		if (!test_bit(br->dead_node, dlm->domain_map) ||
2743 		    !test_bit(br->dead_node, dlm->live_nodes_map))
2744 			mlog(0, "%u not in domain/live_nodes map "
2745 			     "so setting it in reco map manually\n",
2746 			     br->dead_node);
2747 		/* force the recovery cleanup in __dlm_hb_node_down
2748 		 * both of these will be cleared in a moment */
2749 		set_bit(br->dead_node, dlm->domain_map);
2750 		set_bit(br->dead_node, dlm->live_nodes_map);
2751 		__dlm_hb_node_down(dlm, br->dead_node);
2752 	}
2753 	spin_unlock(&dlm->spinlock);
2754 
2755 	dlm_kick_recovery_thread(dlm);
2756 
2757 	mlog(0, "%s: recovery started by node %u, for %u (%u:%u)\n",
2758 	     dlm->name, br->node_idx, br->dead_node,
2759 	     dlm->reco.dead_node, dlm->reco.new_master);
2760 
2761 	dlm_put(dlm);
2762 	return 0;
2763 }
2764 
2765 #define DLM_FINALIZE_STAGE2  0x01
2766 static int dlm_send_finalize_reco_message(struct dlm_ctxt *dlm)
2767 {
2768 	int ret = 0;
2769 	struct dlm_finalize_reco fr;
2770 	struct dlm_node_iter iter;
2771 	int nodenum;
2772 	int status;
2773 	int stage = 1;
2774 
2775 	mlog(0, "finishing recovery for node %s:%u, "
2776 	     "stage %d\n", dlm->name, dlm->reco.dead_node, stage);
2777 
2778 	spin_lock(&dlm->spinlock);
2779 	dlm_node_iter_init(dlm->domain_map, &iter);
2780 	spin_unlock(&dlm->spinlock);
2781 
2782 stage2:
2783 	memset(&fr, 0, sizeof(fr));
2784 	fr.node_idx = dlm->node_num;
2785 	fr.dead_node = dlm->reco.dead_node;
2786 	if (stage == 2)
2787 		fr.flags |= DLM_FINALIZE_STAGE2;
2788 
2789 	while ((nodenum = dlm_node_iter_next(&iter)) >= 0) {
2790 		if (nodenum == dlm->node_num)
2791 			continue;
2792 		ret = o2net_send_message(DLM_FINALIZE_RECO_MSG, dlm->key,
2793 					 &fr, sizeof(fr), nodenum, &status);
2794 		if (ret >= 0)
2795 			ret = status;
2796 		if (ret < 0) {
2797 			mlog(ML_ERROR, "Error %d when sending message %u (key "
2798 			     "0x%x) to node %u\n", ret, DLM_FINALIZE_RECO_MSG,
2799 			     dlm->key, nodenum);
2800 			if (dlm_is_host_down(ret)) {
2801 				/* this has no effect on this recovery
2802 				 * session, so set the status to zero to
2803 				 * finish out the last recovery */
2804 				mlog(ML_ERROR, "node %u went down after this "
2805 				     "node finished recovery.\n", nodenum);
2806 				ret = 0;
2807 				continue;
2808 			}
2809 			break;
2810 		}
2811 	}
2812 	if (stage == 1) {
2813 		/* reset the node_iter back to the top and send finalize2 */
2814 		iter.curnode = -1;
2815 		stage = 2;
2816 		goto stage2;
2817 	}
2818 
2819 	return ret;
2820 }
2821 
2822 int dlm_finalize_reco_handler(struct o2net_msg *msg, u32 len, void *data,
2823 			      void **ret_data)
2824 {
2825 	struct dlm_ctxt *dlm = data;
2826 	struct dlm_finalize_reco *fr = (struct dlm_finalize_reco *)msg->buf;
2827 	int stage = 1;
2828 
2829 	/* ok to return 0, domain has gone away */
2830 	if (!dlm_grab(dlm))
2831 		return 0;
2832 
2833 	if (fr->flags & DLM_FINALIZE_STAGE2)
2834 		stage = 2;
2835 
2836 	mlog(0, "%s: node %u finalizing recovery stage%d of "
2837 	     "node %u (%u:%u)\n", dlm->name, fr->node_idx, stage,
2838 	     fr->dead_node, dlm->reco.dead_node, dlm->reco.new_master);
2839 
2840 	spin_lock(&dlm->spinlock);
2841 
2842 	if (dlm->reco.new_master != fr->node_idx) {
2843 		mlog(ML_ERROR, "node %u sent recovery finalize msg, but node "
2844 		     "%u is supposed to be the new master, dead=%u\n",
2845 		     fr->node_idx, dlm->reco.new_master, fr->dead_node);
2846 		BUG();
2847 	}
2848 	if (dlm->reco.dead_node != fr->dead_node) {
2849 		mlog(ML_ERROR, "node %u sent recovery finalize msg for dead "
2850 		     "node %u, but node %u is supposed to be dead\n",
2851 		     fr->node_idx, fr->dead_node, dlm->reco.dead_node);
2852 		BUG();
2853 	}
2854 
2855 	switch (stage) {
2856 		case 1:
2857 			dlm_finish_local_lockres_recovery(dlm, fr->dead_node, fr->node_idx);
2858 			if (dlm->reco.state & DLM_RECO_STATE_FINALIZE) {
2859 				mlog(ML_ERROR, "%s: received finalize1 from "
2860 				     "new master %u for dead node %u, but "
2861 				     "this node has already received it!\n",
2862 				     dlm->name, fr->node_idx, fr->dead_node);
2863 				dlm_print_reco_node_status(dlm);
2864 				BUG();
2865 			}
2866 			dlm->reco.state |= DLM_RECO_STATE_FINALIZE;
2867 			spin_unlock(&dlm->spinlock);
2868 			break;
2869 		case 2:
2870 			if (!(dlm->reco.state & DLM_RECO_STATE_FINALIZE)) {
2871 				mlog(ML_ERROR, "%s: received finalize2 from "
2872 				     "new master %u for dead node %u, but "
2873 				     "this node did not have finalize1!\n",
2874 				     dlm->name, fr->node_idx, fr->dead_node);
2875 				dlm_print_reco_node_status(dlm);
2876 				BUG();
2877 			}
2878 			dlm->reco.state &= ~DLM_RECO_STATE_FINALIZE;
2879 			spin_unlock(&dlm->spinlock);
2880 			dlm_reset_recovery(dlm);
2881 			dlm_kick_recovery_thread(dlm);
2882 			break;
2883 		default:
2884 			BUG();
2885 	}
2886 
2887 	mlog(0, "%s: recovery done, reco master was %u, dead now %u, master now %u\n",
2888 	     dlm->name, fr->node_idx, dlm->reco.dead_node, dlm->reco.new_master);
2889 
2890 	dlm_put(dlm);
2891 	return 0;
2892 }
2893