xref: /linux/fs/dlm/member.c (revision 447e140e66fd226350b3ce86cffc965eaae4c856)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /******************************************************************************
3 *******************************************************************************
4 **
5 **  Copyright (C) 2005-2011 Red Hat, Inc.  All rights reserved.
6 **
7 **
8 *******************************************************************************
9 ******************************************************************************/
10 
11 #include "dlm_internal.h"
12 #include "lockspace.h"
13 #include "member.h"
14 #include "recoverd.h"
15 #include "recover.h"
16 #include "rcom.h"
17 #include "config.h"
18 #include "midcomms.h"
19 #include "lowcomms.h"
20 
21 int dlm_slots_version(const struct dlm_header *h)
22 {
23 	if ((le32_to_cpu(h->h_version) & 0x0000FFFF) < DLM_HEADER_SLOTS)
24 		return 0;
25 	return 1;
26 }
27 
28 void dlm_slot_save(struct dlm_ls *ls, struct dlm_rcom *rc,
29 		   struct dlm_member *memb)
30 {
31 	struct rcom_config *rf = (struct rcom_config *)rc->rc_buf;
32 
33 	if (!dlm_slots_version(&rc->rc_header))
34 		return;
35 
36 	memb->slot = le16_to_cpu(rf->rf_our_slot);
37 	memb->generation = le32_to_cpu(rf->rf_generation);
38 }
39 
40 void dlm_slots_copy_out(struct dlm_ls *ls, struct dlm_rcom *rc)
41 {
42 	struct dlm_slot *slot;
43 	struct rcom_slot *ro;
44 	int i;
45 
46 	ro = (struct rcom_slot *)(rc->rc_buf + sizeof(struct rcom_config));
47 
48 	/* ls_slots array is sparse, but not rcom_slots */
49 
50 	for (i = 0; i < ls->ls_slots_size; i++) {
51 		slot = &ls->ls_slots[i];
52 		if (!slot->nodeid)
53 			continue;
54 		ro->ro_nodeid = cpu_to_le32(slot->nodeid);
55 		ro->ro_slot = cpu_to_le16(slot->slot);
56 		ro++;
57 	}
58 }
59 
60 #define SLOT_DEBUG_LINE 128
61 
62 static void log_slots(struct dlm_ls *ls, uint32_t gen, int num_slots,
63 		      struct rcom_slot *ro0, struct dlm_slot *array,
64 		      int array_size)
65 {
66 	char line[SLOT_DEBUG_LINE];
67 	int len = SLOT_DEBUG_LINE - 1;
68 	int pos = 0;
69 	int ret, i;
70 
71 	memset(line, 0, sizeof(line));
72 
73 	if (array) {
74 		for (i = 0; i < array_size; i++) {
75 			if (!array[i].nodeid)
76 				continue;
77 
78 			ret = snprintf(line + pos, len - pos, " %d:%d",
79 				       array[i].slot, array[i].nodeid);
80 			if (ret >= len - pos)
81 				break;
82 			pos += ret;
83 		}
84 	} else if (ro0) {
85 		for (i = 0; i < num_slots; i++) {
86 			ret = snprintf(line + pos, len - pos, " %d:%d",
87 				       ro0[i].ro_slot, ro0[i].ro_nodeid);
88 			if (ret >= len - pos)
89 				break;
90 			pos += ret;
91 		}
92 	}
93 
94 	log_rinfo(ls, "generation %u slots %d%s", gen, num_slots, line);
95 }
96 
97 int dlm_slots_copy_in(struct dlm_ls *ls)
98 {
99 	struct dlm_member *memb;
100 	struct dlm_rcom *rc = ls->ls_recover_buf;
101 	struct rcom_config *rf = (struct rcom_config *)rc->rc_buf;
102 	struct rcom_slot *ro0, *ro;
103 	int our_nodeid = dlm_our_nodeid();
104 	int i, num_slots;
105 	uint32_t gen;
106 
107 	if (!dlm_slots_version(&rc->rc_header))
108 		return -1;
109 
110 	gen = le32_to_cpu(rf->rf_generation);
111 	if (gen <= ls->ls_generation) {
112 		log_error(ls, "dlm_slots_copy_in gen %u old %u",
113 			  gen, ls->ls_generation);
114 	}
115 	ls->ls_generation = gen;
116 
117 	num_slots = le16_to_cpu(rf->rf_num_slots);
118 	if (!num_slots)
119 		return -1;
120 
121 	ro0 = (struct rcom_slot *)(rc->rc_buf + sizeof(struct rcom_config));
122 
123 	log_slots(ls, gen, num_slots, ro0, NULL, 0);
124 
125 	list_for_each_entry(memb, &ls->ls_nodes, list) {
126 		for (i = 0, ro = ro0; i < num_slots; i++, ro++) {
127 			if (le32_to_cpu(ro->ro_nodeid) != memb->nodeid)
128 				continue;
129 			memb->slot = le16_to_cpu(ro->ro_slot);
130 			memb->slot_prev = memb->slot;
131 			break;
132 		}
133 
134 		if (memb->nodeid == our_nodeid) {
135 			if (ls->ls_slot && ls->ls_slot != memb->slot) {
136 				log_error(ls, "dlm_slots_copy_in our slot "
137 					  "changed %d %d", ls->ls_slot,
138 					  memb->slot);
139 				return -1;
140 			}
141 
142 			if (!ls->ls_slot)
143 				ls->ls_slot = memb->slot;
144 		}
145 
146 		if (!memb->slot) {
147 			log_error(ls, "dlm_slots_copy_in nodeid %d no slot",
148 				   memb->nodeid);
149 			return -1;
150 		}
151 	}
152 
153 	return 0;
154 }
155 
156 /* for any nodes that do not support slots, we will not have set memb->slot
157    in wait_status_all(), so memb->slot will remain -1, and we will not
158    assign slots or set ls_num_slots here */
159 
160 int dlm_slots_assign(struct dlm_ls *ls, int *num_slots, int *slots_size,
161 		     struct dlm_slot **slots_out, uint32_t *gen_out)
162 {
163 	struct dlm_member *memb;
164 	struct dlm_slot *array;
165 	int our_nodeid = dlm_our_nodeid();
166 	int array_size, max_slots, i;
167 	int need = 0;
168 	int max = 0;
169 	int num = 0;
170 	uint32_t gen = 0;
171 
172 	/* our own memb struct will have slot -1 gen 0 */
173 
174 	list_for_each_entry(memb, &ls->ls_nodes, list) {
175 		if (memb->nodeid == our_nodeid) {
176 			memb->slot = ls->ls_slot;
177 			memb->generation = ls->ls_generation;
178 			break;
179 		}
180 	}
181 
182 	list_for_each_entry(memb, &ls->ls_nodes, list) {
183 		if (memb->generation > gen)
184 			gen = memb->generation;
185 
186 		/* node doesn't support slots */
187 
188 		if (memb->slot == -1)
189 			return -1;
190 
191 		/* node needs a slot assigned */
192 
193 		if (!memb->slot)
194 			need++;
195 
196 		/* node has a slot assigned */
197 
198 		num++;
199 
200 		if (!max || max < memb->slot)
201 			max = memb->slot;
202 
203 		/* sanity check, once slot is assigned it shouldn't change */
204 
205 		if (memb->slot_prev && memb->slot && memb->slot_prev != memb->slot) {
206 			log_error(ls, "nodeid %d slot changed %d %d",
207 				  memb->nodeid, memb->slot_prev, memb->slot);
208 			return -1;
209 		}
210 		memb->slot_prev = memb->slot;
211 	}
212 
213 	array_size = max + need;
214 	array = kcalloc(array_size, sizeof(*array), GFP_NOFS);
215 	if (!array)
216 		return -ENOMEM;
217 
218 	num = 0;
219 
220 	/* fill in slots (offsets) that are used */
221 
222 	list_for_each_entry(memb, &ls->ls_nodes, list) {
223 		if (!memb->slot)
224 			continue;
225 
226 		if (memb->slot > array_size) {
227 			log_error(ls, "invalid slot number %d", memb->slot);
228 			kfree(array);
229 			return -1;
230 		}
231 
232 		array[memb->slot - 1].nodeid = memb->nodeid;
233 		array[memb->slot - 1].slot = memb->slot;
234 		num++;
235 	}
236 
237 	/* assign new slots from unused offsets */
238 
239 	list_for_each_entry(memb, &ls->ls_nodes, list) {
240 		if (memb->slot)
241 			continue;
242 
243 		for (i = 0; i < array_size; i++) {
244 			if (array[i].nodeid)
245 				continue;
246 
247 			memb->slot = i + 1;
248 			memb->slot_prev = memb->slot;
249 			array[i].nodeid = memb->nodeid;
250 			array[i].slot = memb->slot;
251 			num++;
252 
253 			if (!ls->ls_slot && memb->nodeid == our_nodeid)
254 				ls->ls_slot = memb->slot;
255 			break;
256 		}
257 
258 		if (!memb->slot) {
259 			log_error(ls, "no free slot found");
260 			kfree(array);
261 			return -1;
262 		}
263 	}
264 
265 	gen++;
266 
267 	log_slots(ls, gen, num, NULL, array, array_size);
268 
269 	max_slots = (DLM_MAX_APP_BUFSIZE - sizeof(struct dlm_rcom) -
270 		     sizeof(struct rcom_config)) / sizeof(struct rcom_slot);
271 
272 	if (num > max_slots) {
273 		log_error(ls, "num_slots %d exceeds max_slots %d",
274 			  num, max_slots);
275 		kfree(array);
276 		return -1;
277 	}
278 
279 	*gen_out = gen;
280 	*slots_out = array;
281 	*slots_size = array_size;
282 	*num_slots = num;
283 	return 0;
284 }
285 
286 static void add_ordered_member(struct dlm_ls *ls, struct dlm_member *new)
287 {
288 	struct dlm_member *memb = NULL;
289 	struct list_head *tmp;
290 	struct list_head *newlist = &new->list;
291 	struct list_head *head = &ls->ls_nodes;
292 
293 	list_for_each(tmp, head) {
294 		memb = list_entry(tmp, struct dlm_member, list);
295 		if (new->nodeid < memb->nodeid)
296 			break;
297 	}
298 
299 	if (!memb)
300 		list_add_tail(newlist, head);
301 	else {
302 		/* FIXME: can use list macro here */
303 		newlist->prev = tmp->prev;
304 		newlist->next = tmp;
305 		tmp->prev->next = newlist;
306 		tmp->prev = newlist;
307 	}
308 }
309 
310 static int add_remote_member(int nodeid)
311 {
312 	int error;
313 
314 	if (nodeid == dlm_our_nodeid())
315 		return 0;
316 
317 	error = dlm_lowcomms_connect_node(nodeid);
318 	if (error < 0)
319 		return error;
320 
321 	dlm_midcomms_add_member(nodeid);
322 	return 0;
323 }
324 
325 static int dlm_add_member(struct dlm_ls *ls, struct dlm_config_node *node)
326 {
327 	struct dlm_member *memb;
328 	int error;
329 
330 	memb = kzalloc(sizeof(*memb), GFP_NOFS);
331 	if (!memb)
332 		return -ENOMEM;
333 
334 	memb->nodeid = node->nodeid;
335 	memb->weight = node->weight;
336 	memb->comm_seq = node->comm_seq;
337 
338 	error = add_remote_member(node->nodeid);
339 	if (error < 0) {
340 		kfree(memb);
341 		return error;
342 	}
343 
344 	add_ordered_member(ls, memb);
345 	ls->ls_num_nodes++;
346 	return 0;
347 }
348 
349 static struct dlm_member *find_memb(struct list_head *head, int nodeid)
350 {
351 	struct dlm_member *memb;
352 
353 	list_for_each_entry(memb, head, list) {
354 		if (memb->nodeid == nodeid)
355 			return memb;
356 	}
357 	return NULL;
358 }
359 
360 int dlm_is_member(struct dlm_ls *ls, int nodeid)
361 {
362 	if (find_memb(&ls->ls_nodes, nodeid))
363 		return 1;
364 	return 0;
365 }
366 
367 int dlm_is_removed(struct dlm_ls *ls, int nodeid)
368 {
369 	if (find_memb(&ls->ls_nodes_gone, nodeid))
370 		return 1;
371 	return 0;
372 }
373 
374 static void clear_memb_list(struct list_head *head,
375 			    void (*after_del)(int nodeid))
376 {
377 	struct dlm_member *memb;
378 
379 	while (!list_empty(head)) {
380 		memb = list_entry(head->next, struct dlm_member, list);
381 		list_del(&memb->list);
382 		if (after_del)
383 			after_del(memb->nodeid);
384 		kfree(memb);
385 	}
386 }
387 
388 static void remove_remote_member(int nodeid)
389 {
390 	if (nodeid == dlm_our_nodeid())
391 		return;
392 
393 	dlm_midcomms_remove_member(nodeid);
394 }
395 
396 void dlm_clear_members(struct dlm_ls *ls)
397 {
398 	clear_memb_list(&ls->ls_nodes, remove_remote_member);
399 	ls->ls_num_nodes = 0;
400 }
401 
402 void dlm_clear_members_gone(struct dlm_ls *ls)
403 {
404 	clear_memb_list(&ls->ls_nodes_gone, NULL);
405 }
406 
407 static void make_member_array(struct dlm_ls *ls)
408 {
409 	struct dlm_member *memb;
410 	int i, w, x = 0, total = 0, all_zero = 0, *array;
411 
412 	kfree(ls->ls_node_array);
413 	ls->ls_node_array = NULL;
414 
415 	list_for_each_entry(memb, &ls->ls_nodes, list) {
416 		if (memb->weight)
417 			total += memb->weight;
418 	}
419 
420 	/* all nodes revert to weight of 1 if all have weight 0 */
421 
422 	if (!total) {
423 		total = ls->ls_num_nodes;
424 		all_zero = 1;
425 	}
426 
427 	ls->ls_total_weight = total;
428 	array = kmalloc_array(total, sizeof(*array), GFP_NOFS);
429 	if (!array)
430 		return;
431 
432 	list_for_each_entry(memb, &ls->ls_nodes, list) {
433 		if (!all_zero && !memb->weight)
434 			continue;
435 
436 		if (all_zero)
437 			w = 1;
438 		else
439 			w = memb->weight;
440 
441 		DLM_ASSERT(x < total, printk("total %d x %d\n", total, x););
442 
443 		for (i = 0; i < w; i++)
444 			array[x++] = memb->nodeid;
445 	}
446 
447 	ls->ls_node_array = array;
448 }
449 
450 /* send a status request to all members just to establish comms connections */
451 
452 static int ping_members(struct dlm_ls *ls, uint64_t seq)
453 {
454 	struct dlm_member *memb;
455 	int error = 0;
456 
457 	list_for_each_entry(memb, &ls->ls_nodes, list) {
458 		if (dlm_recovery_stopped(ls)) {
459 			error = -EINTR;
460 			break;
461 		}
462 		error = dlm_rcom_status(ls, memb->nodeid, 0, seq);
463 		if (error)
464 			break;
465 	}
466 	if (error)
467 		log_rinfo(ls, "ping_members aborted %d last nodeid %d",
468 			  error, ls->ls_recover_nodeid);
469 	return error;
470 }
471 
472 static void dlm_lsop_recover_prep(struct dlm_ls *ls)
473 {
474 	if (!ls->ls_ops || !ls->ls_ops->recover_prep)
475 		return;
476 	ls->ls_ops->recover_prep(ls->ls_ops_arg);
477 }
478 
479 static void dlm_lsop_recover_slot(struct dlm_ls *ls, struct dlm_member *memb)
480 {
481 	struct dlm_slot slot;
482 	uint32_t seq;
483 	int error;
484 
485 	if (!ls->ls_ops || !ls->ls_ops->recover_slot)
486 		return;
487 
488 	/* if there is no comms connection with this node
489 	   or the present comms connection is newer
490 	   than the one when this member was added, then
491 	   we consider the node to have failed (versus
492 	   being removed due to dlm_release_lockspace) */
493 
494 	error = dlm_comm_seq(memb->nodeid, &seq);
495 
496 	if (!error && seq == memb->comm_seq)
497 		return;
498 
499 	slot.nodeid = memb->nodeid;
500 	slot.slot = memb->slot;
501 
502 	ls->ls_ops->recover_slot(ls->ls_ops_arg, &slot);
503 }
504 
505 void dlm_lsop_recover_done(struct dlm_ls *ls)
506 {
507 	struct dlm_member *memb;
508 	struct dlm_slot *slots;
509 	int i, num;
510 
511 	if (!ls->ls_ops || !ls->ls_ops->recover_done)
512 		return;
513 
514 	num = ls->ls_num_nodes;
515 	slots = kcalloc(num, sizeof(*slots), GFP_KERNEL);
516 	if (!slots)
517 		return;
518 
519 	i = 0;
520 	list_for_each_entry(memb, &ls->ls_nodes, list) {
521 		if (i == num) {
522 			log_error(ls, "dlm_lsop_recover_done bad num %d", num);
523 			goto out;
524 		}
525 		slots[i].nodeid = memb->nodeid;
526 		slots[i].slot = memb->slot;
527 		i++;
528 	}
529 
530 	ls->ls_ops->recover_done(ls->ls_ops_arg, slots, num,
531 				 ls->ls_slot, ls->ls_generation);
532  out:
533 	kfree(slots);
534 }
535 
536 static struct dlm_config_node *find_config_node(struct dlm_recover *rv,
537 						int nodeid)
538 {
539 	int i;
540 
541 	for (i = 0; i < rv->nodes_count; i++) {
542 		if (rv->nodes[i].nodeid == nodeid)
543 			return &rv->nodes[i];
544 	}
545 	return NULL;
546 }
547 
548 int dlm_recover_members(struct dlm_ls *ls, struct dlm_recover *rv, int *neg_out)
549 {
550 	struct dlm_member *memb, *safe;
551 	struct dlm_config_node *node;
552 	int i, error, neg = 0, low = -1;
553 
554 	/* previously removed members that we've not finished removing need to
555 	 * count as a negative change so the "neg" recovery steps will happen
556 	 *
557 	 * This functionality must report all member changes to lsops or
558 	 * midcomms layer and must never return before.
559 	 */
560 
561 	list_for_each_entry(memb, &ls->ls_nodes_gone, list) {
562 		log_rinfo(ls, "prev removed member %d", memb->nodeid);
563 		neg++;
564 	}
565 
566 	/* move departed members from ls_nodes to ls_nodes_gone */
567 
568 	list_for_each_entry_safe(memb, safe, &ls->ls_nodes, list) {
569 		node = find_config_node(rv, memb->nodeid);
570 		if (node && !node->new)
571 			continue;
572 
573 		if (!node) {
574 			log_rinfo(ls, "remove member %d", memb->nodeid);
575 		} else {
576 			/* removed and re-added */
577 			log_rinfo(ls, "remove member %d comm_seq %u %u",
578 				  memb->nodeid, memb->comm_seq, node->comm_seq);
579 		}
580 
581 		neg++;
582 		list_move(&memb->list, &ls->ls_nodes_gone);
583 		remove_remote_member(memb->nodeid);
584 		ls->ls_num_nodes--;
585 		dlm_lsop_recover_slot(ls, memb);
586 	}
587 
588 	/* add new members to ls_nodes */
589 
590 	for (i = 0; i < rv->nodes_count; i++) {
591 		node = &rv->nodes[i];
592 		if (dlm_is_member(ls, node->nodeid))
593 			continue;
594 		error = dlm_add_member(ls, node);
595 		if (error)
596 			return error;
597 
598 		log_rinfo(ls, "add member %d", node->nodeid);
599 	}
600 
601 	list_for_each_entry(memb, &ls->ls_nodes, list) {
602 		if (low == -1 || memb->nodeid < low)
603 			low = memb->nodeid;
604 	}
605 	ls->ls_low_nodeid = low;
606 
607 	make_member_array(ls);
608 	*neg_out = neg;
609 
610 	error = ping_members(ls, rv->seq);
611 	log_rinfo(ls, "dlm_recover_members %d nodes", ls->ls_num_nodes);
612 	return error;
613 }
614 
615 /* Userspace guarantees that dlm_ls_stop() has completed on all nodes before
616    dlm_ls_start() is called on any of them to start the new recovery. */
617 
618 int dlm_ls_stop(struct dlm_ls *ls)
619 {
620 	int new;
621 
622 	/*
623 	 * Prevent dlm_recv from being in the middle of something when we do
624 	 * the stop.  This includes ensuring dlm_recv isn't processing a
625 	 * recovery message (rcom), while dlm_recoverd is aborting and
626 	 * resetting things from an in-progress recovery.  i.e. we want
627 	 * dlm_recoverd to abort its recovery without worrying about dlm_recv
628 	 * processing an rcom at the same time.  Stopping dlm_recv also makes
629 	 * it easy for dlm_receive_message() to check locking stopped and add a
630 	 * message to the requestqueue without races.
631 	 */
632 
633 	write_lock_bh(&ls->ls_recv_active);
634 
635 	/*
636 	 * Abort any recovery that's in progress (see RECOVER_STOP,
637 	 * dlm_recovery_stopped()) and tell any other threads running in the
638 	 * dlm to quit any processing (see RUNNING, dlm_locking_stopped()).
639 	 */
640 
641 	spin_lock_bh(&ls->ls_recover_lock);
642 	set_bit(LSFL_RECOVER_STOP, &ls->ls_flags);
643 	new = test_and_clear_bit(LSFL_RUNNING, &ls->ls_flags);
644 	if (new)
645 		timer_delete_sync(&ls->ls_timer);
646 	ls->ls_recover_seq++;
647 
648 	/* activate requestqueue and stop processing */
649 	write_lock_bh(&ls->ls_requestqueue_lock);
650 	set_bit(LSFL_RECV_MSG_BLOCKED, &ls->ls_flags);
651 	write_unlock_bh(&ls->ls_requestqueue_lock);
652 	spin_unlock_bh(&ls->ls_recover_lock);
653 
654 	/*
655 	 * Let dlm_recv run again, now any normal messages will be saved on the
656 	 * requestqueue for later.
657 	 */
658 
659 	write_unlock_bh(&ls->ls_recv_active);
660 
661 	/*
662 	 * This in_recovery lock does two things:
663 	 * 1) Keeps this function from returning until all threads are out
664 	 *    of locking routines and locking is truly stopped.
665 	 * 2) Keeps any new requests from being processed until it's unlocked
666 	 *    when recovery is complete.
667 	 */
668 
669 	if (new) {
670 		set_bit(LSFL_RECOVER_DOWN, &ls->ls_flags);
671 		wake_up_process(ls->ls_recoverd_task);
672 		wait_event(ls->ls_recover_lock_wait,
673 			   test_bit(LSFL_RECOVER_LOCK, &ls->ls_flags));
674 	}
675 
676 	/*
677 	 * The recoverd suspend/resume makes sure that dlm_recoverd (if
678 	 * running) has noticed RECOVER_STOP above and quit processing the
679 	 * previous recovery.
680 	 */
681 
682 	dlm_recoverd_suspend(ls);
683 
684 	spin_lock_bh(&ls->ls_recover_lock);
685 	kfree(ls->ls_slots);
686 	ls->ls_slots = NULL;
687 	ls->ls_num_slots = 0;
688 	ls->ls_slots_size = 0;
689 	ls->ls_recover_status = 0;
690 	spin_unlock_bh(&ls->ls_recover_lock);
691 
692 	dlm_recoverd_resume(ls);
693 
694 	if (!ls->ls_recover_begin)
695 		ls->ls_recover_begin = jiffies;
696 
697 	/* call recover_prep ops only once and not multiple times
698 	 * for each possible dlm_ls_stop() when recovery is already
699 	 * stopped.
700 	 *
701 	 * If we successful was able to clear LSFL_RUNNING bit and
702 	 * it was set we know it is the first dlm_ls_stop() call.
703 	 */
704 	if (new)
705 		dlm_lsop_recover_prep(ls);
706 
707 	return 0;
708 }
709 
710 int dlm_ls_start(struct dlm_ls *ls)
711 {
712 	struct dlm_recover *rv, *rv_old;
713 	struct dlm_config_node *nodes = NULL;
714 	int error, count;
715 
716 	rv = kzalloc(sizeof(*rv), GFP_NOFS);
717 	if (!rv)
718 		return -ENOMEM;
719 
720 	error = dlm_config_nodes(ls->ls_name, &nodes, &count);
721 	if (error < 0)
722 		goto fail_rv;
723 
724 	spin_lock_bh(&ls->ls_recover_lock);
725 
726 	/* the lockspace needs to be stopped before it can be started */
727 
728 	if (!dlm_locking_stopped(ls)) {
729 		spin_unlock_bh(&ls->ls_recover_lock);
730 		log_error(ls, "start ignored: lockspace running");
731 		error = -EINVAL;
732 		goto fail;
733 	}
734 
735 	rv->nodes = nodes;
736 	rv->nodes_count = count;
737 	rv->seq = ++ls->ls_recover_seq;
738 	rv_old = ls->ls_recover_args;
739 	ls->ls_recover_args = rv;
740 	spin_unlock_bh(&ls->ls_recover_lock);
741 
742 	if (rv_old) {
743 		log_error(ls, "unused recovery %llx %d",
744 			  (unsigned long long)rv_old->seq, rv_old->nodes_count);
745 		kfree(rv_old->nodes);
746 		kfree(rv_old);
747 	}
748 
749 	set_bit(LSFL_RECOVER_WORK, &ls->ls_flags);
750 	wake_up_process(ls->ls_recoverd_task);
751 	return 0;
752 
753  fail:
754 	kfree(nodes);
755  fail_rv:
756 	kfree(rv);
757 	return error;
758 }
759 
760