dlm: convert rsb list to rb_tree
[linux-2.6.git] / fs / dlm / recover.c
1 /******************************************************************************
2 *******************************************************************************
3 **
4 **  Copyright (C) Sistina Software, Inc.  1997-2003  All rights reserved.
5 **  Copyright (C) 2004-2005 Red Hat, Inc.  All rights reserved.
6 **
7 **  This copyrighted material is made available to anyone wishing to use,
8 **  modify, copy, or redistribute it subject to the terms and conditions
9 **  of the GNU General Public License v.2.
10 **
11 *******************************************************************************
12 ******************************************************************************/
13
14 #include "dlm_internal.h"
15 #include "lockspace.h"
16 #include "dir.h"
17 #include "config.h"
18 #include "ast.h"
19 #include "memory.h"
20 #include "rcom.h"
21 #include "lock.h"
22 #include "lowcomms.h"
23 #include "member.h"
24 #include "recover.h"
25
26
27 /*
28  * Recovery waiting routines: these functions wait for a particular reply from
29  * a remote node, or for the remote node to report a certain status.  They need
30  * to abort if the lockspace is stopped indicating a node has failed (perhaps
31  * the one being waited for).
32  */
33
34 /*
35  * Wait until given function returns non-zero or lockspace is stopped
36  * (LS_RECOVERY_STOP set due to failure of a node in ls_nodes).  When another
37  * function thinks it could have completed the waited-on task, they should wake
38  * up ls_wait_general to get an immediate response rather than waiting for the
39  * timer to detect the result.  A timer wakes us up periodically while waiting
40  * to see if we should abort due to a node failure.  This should only be called
41  * by the dlm_recoverd thread.
42  */
43
44 static void dlm_wait_timer_fn(unsigned long data)
45 {
46         struct dlm_ls *ls = (struct dlm_ls *) data;
47         mod_timer(&ls->ls_timer, jiffies + (dlm_config.ci_recover_timer * HZ));
48         wake_up(&ls->ls_wait_general);
49 }
50
51 int dlm_wait_function(struct dlm_ls *ls, int (*testfn) (struct dlm_ls *ls))
52 {
53         int error = 0;
54
55         init_timer(&ls->ls_timer);
56         ls->ls_timer.function = dlm_wait_timer_fn;
57         ls->ls_timer.data = (long) ls;
58         ls->ls_timer.expires = jiffies + (dlm_config.ci_recover_timer * HZ);
59         add_timer(&ls->ls_timer);
60
61         wait_event(ls->ls_wait_general, testfn(ls) || dlm_recovery_stopped(ls));
62         del_timer_sync(&ls->ls_timer);
63
64         if (dlm_recovery_stopped(ls)) {
65                 log_debug(ls, "dlm_wait_function aborted");
66                 error = -EINTR;
67         }
68         return error;
69 }
70
71 /*
72  * An efficient way for all nodes to wait for all others to have a certain
73  * status.  The node with the lowest nodeid polls all the others for their
74  * status (wait_status_all) and all the others poll the node with the low id
75  * for its accumulated result (wait_status_low).  When all nodes have set
76  * status flag X, then status flag X_ALL will be set on the low nodeid.
77  */
78
79 uint32_t dlm_recover_status(struct dlm_ls *ls)
80 {
81         uint32_t status;
82         spin_lock(&ls->ls_recover_lock);
83         status = ls->ls_recover_status;
84         spin_unlock(&ls->ls_recover_lock);
85         return status;
86 }
87
88 void dlm_set_recover_status(struct dlm_ls *ls, uint32_t status)
89 {
90         spin_lock(&ls->ls_recover_lock);
91         ls->ls_recover_status |= status;
92         spin_unlock(&ls->ls_recover_lock);
93 }
94
95 static int wait_status_all(struct dlm_ls *ls, uint32_t wait_status)
96 {
97         struct dlm_rcom *rc = ls->ls_recover_buf;
98         struct dlm_member *memb;
99         int error = 0, delay;
100
101         list_for_each_entry(memb, &ls->ls_nodes, list) {
102                 delay = 0;
103                 for (;;) {
104                         if (dlm_recovery_stopped(ls)) {
105                                 error = -EINTR;
106                                 goto out;
107                         }
108
109                         error = dlm_rcom_status(ls, memb->nodeid);
110                         if (error)
111                                 goto out;
112
113                         if (rc->rc_result & wait_status)
114                                 break;
115                         if (delay < 1000)
116                                 delay += 20;
117                         msleep(delay);
118                 }
119         }
120  out:
121         return error;
122 }
123
124 static int wait_status_low(struct dlm_ls *ls, uint32_t wait_status)
125 {
126         struct dlm_rcom *rc = ls->ls_recover_buf;
127         int error = 0, delay = 0, nodeid = ls->ls_low_nodeid;
128
129         for (;;) {
130                 if (dlm_recovery_stopped(ls)) {
131                         error = -EINTR;
132                         goto out;
133                 }
134
135                 error = dlm_rcom_status(ls, nodeid);
136                 if (error)
137                         break;
138
139                 if (rc->rc_result & wait_status)
140                         break;
141                 if (delay < 1000)
142                         delay += 20;
143                 msleep(delay);
144         }
145  out:
146         return error;
147 }
148
149 static int wait_status(struct dlm_ls *ls, uint32_t status)
150 {
151         uint32_t status_all = status << 1;
152         int error;
153
154         if (ls->ls_low_nodeid == dlm_our_nodeid()) {
155                 error = wait_status_all(ls, status);
156                 if (!error)
157                         dlm_set_recover_status(ls, status_all);
158         } else
159                 error = wait_status_low(ls, status_all);
160
161         return error;
162 }
163
164 int dlm_recover_members_wait(struct dlm_ls *ls)
165 {
166         return wait_status(ls, DLM_RS_NODES);
167 }
168
169 int dlm_recover_directory_wait(struct dlm_ls *ls)
170 {
171         return wait_status(ls, DLM_RS_DIR);
172 }
173
174 int dlm_recover_locks_wait(struct dlm_ls *ls)
175 {
176         return wait_status(ls, DLM_RS_LOCKS);
177 }
178
179 int dlm_recover_done_wait(struct dlm_ls *ls)
180 {
181         return wait_status(ls, DLM_RS_DONE);
182 }
183
184 /*
185  * The recover_list contains all the rsb's for which we've requested the new
186  * master nodeid.  As replies are returned from the resource directories the
187  * rsb's are removed from the list.  When the list is empty we're done.
188  *
189  * The recover_list is later similarly used for all rsb's for which we've sent
190  * new lkb's and need to receive new corresponding lkid's.
191  *
192  * We use the address of the rsb struct as a simple local identifier for the
193  * rsb so we can match an rcom reply with the rsb it was sent for.
194  */
195
196 static int recover_list_empty(struct dlm_ls *ls)
197 {
198         int empty;
199
200         spin_lock(&ls->ls_recover_list_lock);
201         empty = list_empty(&ls->ls_recover_list);
202         spin_unlock(&ls->ls_recover_list_lock);
203
204         return empty;
205 }
206
207 static void recover_list_add(struct dlm_rsb *r)
208 {
209         struct dlm_ls *ls = r->res_ls;
210
211         spin_lock(&ls->ls_recover_list_lock);
212         if (list_empty(&r->res_recover_list)) {
213                 list_add_tail(&r->res_recover_list, &ls->ls_recover_list);
214                 ls->ls_recover_list_count++;
215                 dlm_hold_rsb(r);
216         }
217         spin_unlock(&ls->ls_recover_list_lock);
218 }
219
220 static void recover_list_del(struct dlm_rsb *r)
221 {
222         struct dlm_ls *ls = r->res_ls;
223
224         spin_lock(&ls->ls_recover_list_lock);
225         list_del_init(&r->res_recover_list);
226         ls->ls_recover_list_count--;
227         spin_unlock(&ls->ls_recover_list_lock);
228
229         dlm_put_rsb(r);
230 }
231
232 static struct dlm_rsb *recover_list_find(struct dlm_ls *ls, uint64_t id)
233 {
234         struct dlm_rsb *r = NULL;
235
236         spin_lock(&ls->ls_recover_list_lock);
237
238         list_for_each_entry(r, &ls->ls_recover_list, res_recover_list) {
239                 if (id == (unsigned long) r)
240                         goto out;
241         }
242         r = NULL;
243  out:
244         spin_unlock(&ls->ls_recover_list_lock);
245         return r;
246 }
247
248 static void recover_list_clear(struct dlm_ls *ls)
249 {
250         struct dlm_rsb *r, *s;
251
252         spin_lock(&ls->ls_recover_list_lock);
253         list_for_each_entry_safe(r, s, &ls->ls_recover_list, res_recover_list) {
254                 list_del_init(&r->res_recover_list);
255                 r->res_recover_locks_count = 0;
256                 dlm_put_rsb(r);
257                 ls->ls_recover_list_count--;
258         }
259
260         if (ls->ls_recover_list_count != 0) {
261                 log_error(ls, "warning: recover_list_count %d",
262                           ls->ls_recover_list_count);
263                 ls->ls_recover_list_count = 0;
264         }
265         spin_unlock(&ls->ls_recover_list_lock);
266 }
267
268
269 /* Master recovery: find new master node for rsb's that were
270    mastered on nodes that have been removed.
271
272    dlm_recover_masters
273    recover_master
274    dlm_send_rcom_lookup            ->  receive_rcom_lookup
275                                        dlm_dir_lookup
276    receive_rcom_lookup_reply       <-
277    dlm_recover_master_reply
278    set_new_master
279    set_master_lkbs
280    set_lock_master
281 */
282
283 /*
284  * Set the lock master for all LKBs in a lock queue
285  * If we are the new master of the rsb, we may have received new
286  * MSTCPY locks from other nodes already which we need to ignore
287  * when setting the new nodeid.
288  */
289
290 static void set_lock_master(struct list_head *queue, int nodeid)
291 {
292         struct dlm_lkb *lkb;
293
294         list_for_each_entry(lkb, queue, lkb_statequeue)
295                 if (!(lkb->lkb_flags & DLM_IFL_MSTCPY))
296                         lkb->lkb_nodeid = nodeid;
297 }
298
299 static void set_master_lkbs(struct dlm_rsb *r)
300 {
301         set_lock_master(&r->res_grantqueue, r->res_nodeid);
302         set_lock_master(&r->res_convertqueue, r->res_nodeid);
303         set_lock_master(&r->res_waitqueue, r->res_nodeid);
304 }
305
306 /*
307  * Propagate the new master nodeid to locks
308  * The NEW_MASTER flag tells dlm_recover_locks() which rsb's to consider.
309  * The NEW_MASTER2 flag tells recover_lvb() and set_locks_purged() which
310  * rsb's to consider.
311  */
312
313 static void set_new_master(struct dlm_rsb *r, int nodeid)
314 {
315         lock_rsb(r);
316         r->res_nodeid = nodeid;
317         set_master_lkbs(r);
318         rsb_set_flag(r, RSB_NEW_MASTER);
319         rsb_set_flag(r, RSB_NEW_MASTER2);
320         unlock_rsb(r);
321 }
322
323 /*
324  * We do async lookups on rsb's that need new masters.  The rsb's
325  * waiting for a lookup reply are kept on the recover_list.
326  */
327
328 static int recover_master(struct dlm_rsb *r)
329 {
330         struct dlm_ls *ls = r->res_ls;
331         int error, dir_nodeid, ret_nodeid, our_nodeid = dlm_our_nodeid();
332
333         dir_nodeid = dlm_dir_nodeid(r);
334
335         if (dir_nodeid == our_nodeid) {
336                 error = dlm_dir_lookup(ls, our_nodeid, r->res_name,
337                                        r->res_length, &ret_nodeid);
338                 if (error)
339                         log_error(ls, "recover dir lookup error %d", error);
340
341                 if (ret_nodeid == our_nodeid)
342                         ret_nodeid = 0;
343                 set_new_master(r, ret_nodeid);
344         } else {
345                 recover_list_add(r);
346                 error = dlm_send_rcom_lookup(r, dir_nodeid);
347         }
348
349         return error;
350 }
351
352 /*
353  * When not using a directory, most resource names will hash to a new static
354  * master nodeid and the resource will need to be remastered.
355  */
356
357 static int recover_master_static(struct dlm_rsb *r)
358 {
359         int master = dlm_dir_nodeid(r);
360
361         if (master == dlm_our_nodeid())
362                 master = 0;
363
364         if (r->res_nodeid != master) {
365                 if (is_master(r))
366                         dlm_purge_mstcpy_locks(r);
367                 set_new_master(r, master);
368                 return 1;
369         }
370         return 0;
371 }
372
373 /*
374  * Go through local root resources and for each rsb which has a master which
375  * has departed, get the new master nodeid from the directory.  The dir will
376  * assign mastery to the first node to look up the new master.  That means
377  * we'll discover in this lookup if we're the new master of any rsb's.
378  *
379  * We fire off all the dir lookup requests individually and asynchronously to
380  * the correct dir node.
381  */
382
383 int dlm_recover_masters(struct dlm_ls *ls)
384 {
385         struct dlm_rsb *r;
386         int error = 0, count = 0;
387
388         log_debug(ls, "dlm_recover_masters");
389
390         down_read(&ls->ls_root_sem);
391         list_for_each_entry(r, &ls->ls_root_list, res_root_list) {
392                 if (dlm_recovery_stopped(ls)) {
393                         up_read(&ls->ls_root_sem);
394                         error = -EINTR;
395                         goto out;
396                 }
397
398                 if (dlm_no_directory(ls))
399                         count += recover_master_static(r);
400                 else if (!is_master(r) &&
401                          (dlm_is_removed(ls, r->res_nodeid) ||
402                           rsb_flag(r, RSB_NEW_MASTER))) {
403                         recover_master(r);
404                         count++;
405                 }
406
407                 schedule();
408         }
409         up_read(&ls->ls_root_sem);
410
411         log_debug(ls, "dlm_recover_masters %d resources", count);
412
413         error = dlm_wait_function(ls, &recover_list_empty);
414  out:
415         if (error)
416                 recover_list_clear(ls);
417         return error;
418 }
419
420 int dlm_recover_master_reply(struct dlm_ls *ls, struct dlm_rcom *rc)
421 {
422         struct dlm_rsb *r;
423         int nodeid;
424
425         r = recover_list_find(ls, rc->rc_id);
426         if (!r) {
427                 log_error(ls, "dlm_recover_master_reply no id %llx",
428                           (unsigned long long)rc->rc_id);
429                 goto out;
430         }
431
432         nodeid = rc->rc_result;
433         if (nodeid == dlm_our_nodeid())
434                 nodeid = 0;
435
436         set_new_master(r, nodeid);
437         recover_list_del(r);
438
439         if (recover_list_empty(ls))
440                 wake_up(&ls->ls_wait_general);
441  out:
442         return 0;
443 }
444
445
446 /* Lock recovery: rebuild the process-copy locks we hold on a
447    remastered rsb on the new rsb master.
448
449    dlm_recover_locks
450    recover_locks
451    recover_locks_queue
452    dlm_send_rcom_lock              ->  receive_rcom_lock
453                                        dlm_recover_master_copy
454    receive_rcom_lock_reply         <-
455    dlm_recover_process_copy
456 */
457
458
459 /*
460  * keep a count of the number of lkb's we send to the new master; when we get
461  * an equal number of replies then recovery for the rsb is done
462  */
463
464 static int recover_locks_queue(struct dlm_rsb *r, struct list_head *head)
465 {
466         struct dlm_lkb *lkb;
467         int error = 0;
468
469         list_for_each_entry(lkb, head, lkb_statequeue) {
470                 error = dlm_send_rcom_lock(r, lkb);
471                 if (error)
472                         break;
473                 r->res_recover_locks_count++;
474         }
475
476         return error;
477 }
478
479 static int recover_locks(struct dlm_rsb *r)
480 {
481         int error = 0;
482
483         lock_rsb(r);
484
485         DLM_ASSERT(!r->res_recover_locks_count, dlm_dump_rsb(r););
486
487         error = recover_locks_queue(r, &r->res_grantqueue);
488         if (error)
489                 goto out;
490         error = recover_locks_queue(r, &r->res_convertqueue);
491         if (error)
492                 goto out;
493         error = recover_locks_queue(r, &r->res_waitqueue);
494         if (error)
495                 goto out;
496
497         if (r->res_recover_locks_count)
498                 recover_list_add(r);
499         else
500                 rsb_clear_flag(r, RSB_NEW_MASTER);
501  out:
502         unlock_rsb(r);
503         return error;
504 }
505
506 int dlm_recover_locks(struct dlm_ls *ls)
507 {
508         struct dlm_rsb *r;
509         int error, count = 0;
510
511         log_debug(ls, "dlm_recover_locks");
512
513         down_read(&ls->ls_root_sem);
514         list_for_each_entry(r, &ls->ls_root_list, res_root_list) {
515                 if (is_master(r)) {
516                         rsb_clear_flag(r, RSB_NEW_MASTER);
517                         continue;
518                 }
519
520                 if (!rsb_flag(r, RSB_NEW_MASTER))
521                         continue;
522
523                 if (dlm_recovery_stopped(ls)) {
524                         error = -EINTR;
525                         up_read(&ls->ls_root_sem);
526                         goto out;
527                 }
528
529                 error = recover_locks(r);
530                 if (error) {
531                         up_read(&ls->ls_root_sem);
532                         goto out;
533                 }
534
535                 count += r->res_recover_locks_count;
536         }
537         up_read(&ls->ls_root_sem);
538
539         log_debug(ls, "dlm_recover_locks %d locks", count);
540
541         error = dlm_wait_function(ls, &recover_list_empty);
542  out:
543         if (error)
544                 recover_list_clear(ls);
545         else
546                 dlm_set_recover_status(ls, DLM_RS_LOCKS);
547         return error;
548 }
549
550 void dlm_recovered_lock(struct dlm_rsb *r)
551 {
552         DLM_ASSERT(rsb_flag(r, RSB_NEW_MASTER), dlm_dump_rsb(r););
553
554         r->res_recover_locks_count--;
555         if (!r->res_recover_locks_count) {
556                 rsb_clear_flag(r, RSB_NEW_MASTER);
557                 recover_list_del(r);
558         }
559
560         if (recover_list_empty(r->res_ls))
561                 wake_up(&r->res_ls->ls_wait_general);
562 }
563
564 /*
565  * The lvb needs to be recovered on all master rsb's.  This includes setting
566  * the VALNOTVALID flag if necessary, and determining the correct lvb contents
567  * based on the lvb's of the locks held on the rsb.
568  *
569  * RSB_VALNOTVALID is set if there are only NL/CR locks on the rsb.  If it
570  * was already set prior to recovery, it's not cleared, regardless of locks.
571  *
572  * The LVB contents are only considered for changing when this is a new master
573  * of the rsb (NEW_MASTER2).  Then, the rsb's lvb is taken from any lkb with
574  * mode > CR.  If no lkb's exist with mode above CR, the lvb contents are taken
575  * from the lkb with the largest lvb sequence number.
576  */
577
578 static void recover_lvb(struct dlm_rsb *r)
579 {
580         struct dlm_lkb *lkb, *high_lkb = NULL;
581         uint32_t high_seq = 0;
582         int lock_lvb_exists = 0;
583         int big_lock_exists = 0;
584         int lvblen = r->res_ls->ls_lvblen;
585
586         list_for_each_entry(lkb, &r->res_grantqueue, lkb_statequeue) {
587                 if (!(lkb->lkb_exflags & DLM_LKF_VALBLK))
588                         continue;
589
590                 lock_lvb_exists = 1;
591
592                 if (lkb->lkb_grmode > DLM_LOCK_CR) {
593                         big_lock_exists = 1;
594                         goto setflag;
595                 }
596
597                 if (((int)lkb->lkb_lvbseq - (int)high_seq) >= 0) {
598                         high_lkb = lkb;
599                         high_seq = lkb->lkb_lvbseq;
600                 }
601         }
602
603         list_for_each_entry(lkb, &r->res_convertqueue, lkb_statequeue) {
604                 if (!(lkb->lkb_exflags & DLM_LKF_VALBLK))
605                         continue;
606
607                 lock_lvb_exists = 1;
608
609                 if (lkb->lkb_grmode > DLM_LOCK_CR) {
610                         big_lock_exists = 1;
611                         goto setflag;
612                 }
613
614                 if (((int)lkb->lkb_lvbseq - (int)high_seq) >= 0) {
615                         high_lkb = lkb;
616                         high_seq = lkb->lkb_lvbseq;
617                 }
618         }
619
620  setflag:
621         if (!lock_lvb_exists)
622                 goto out;
623
624         if (!big_lock_exists)
625                 rsb_set_flag(r, RSB_VALNOTVALID);
626
627         /* don't mess with the lvb unless we're the new master */
628         if (!rsb_flag(r, RSB_NEW_MASTER2))
629                 goto out;
630
631         if (!r->res_lvbptr) {
632                 r->res_lvbptr = dlm_allocate_lvb(r->res_ls);
633                 if (!r->res_lvbptr)
634                         goto out;
635         }
636
637         if (big_lock_exists) {
638                 r->res_lvbseq = lkb->lkb_lvbseq;
639                 memcpy(r->res_lvbptr, lkb->lkb_lvbptr, lvblen);
640         } else if (high_lkb) {
641                 r->res_lvbseq = high_lkb->lkb_lvbseq;
642                 memcpy(r->res_lvbptr, high_lkb->lkb_lvbptr, lvblen);
643         } else {
644                 r->res_lvbseq = 0;
645                 memset(r->res_lvbptr, 0, lvblen);
646         }
647  out:
648         return;
649 }
650
651 /* All master rsb's flagged RECOVER_CONVERT need to be looked at.  The locks
652    converting PR->CW or CW->PR need to have their lkb_grmode set. */
653
654 static void recover_conversion(struct dlm_rsb *r)
655 {
656         struct dlm_lkb *lkb;
657         int grmode = -1;
658
659         list_for_each_entry(lkb, &r->res_grantqueue, lkb_statequeue) {
660                 if (lkb->lkb_grmode == DLM_LOCK_PR ||
661                     lkb->lkb_grmode == DLM_LOCK_CW) {
662                         grmode = lkb->lkb_grmode;
663                         break;
664                 }
665         }
666
667         list_for_each_entry(lkb, &r->res_convertqueue, lkb_statequeue) {
668                 if (lkb->lkb_grmode != DLM_LOCK_IV)
669                         continue;
670                 if (grmode == -1)
671                         lkb->lkb_grmode = lkb->lkb_rqmode;
672                 else
673                         lkb->lkb_grmode = grmode;
674         }
675 }
676
677 /* We've become the new master for this rsb and waiting/converting locks may
678    need to be granted in dlm_grant_after_purge() due to locks that may have
679    existed from a removed node. */
680
681 static void set_locks_purged(struct dlm_rsb *r)
682 {
683         if (!list_empty(&r->res_waitqueue) || !list_empty(&r->res_convertqueue))
684                 rsb_set_flag(r, RSB_LOCKS_PURGED);
685 }
686
687 void dlm_recover_rsbs(struct dlm_ls *ls)
688 {
689         struct dlm_rsb *r;
690         int count = 0;
691
692         log_debug(ls, "dlm_recover_rsbs");
693
694         down_read(&ls->ls_root_sem);
695         list_for_each_entry(r, &ls->ls_root_list, res_root_list) {
696                 lock_rsb(r);
697                 if (is_master(r)) {
698                         if (rsb_flag(r, RSB_RECOVER_CONVERT))
699                                 recover_conversion(r);
700                         if (rsb_flag(r, RSB_NEW_MASTER2))
701                                 set_locks_purged(r);
702                         recover_lvb(r);
703                         count++;
704                 }
705                 rsb_clear_flag(r, RSB_RECOVER_CONVERT);
706                 rsb_clear_flag(r, RSB_NEW_MASTER2);
707                 unlock_rsb(r);
708         }
709         up_read(&ls->ls_root_sem);
710
711         log_debug(ls, "dlm_recover_rsbs %d rsbs", count);
712 }
713
714 /* Create a single list of all root rsb's to be used during recovery */
715
716 int dlm_create_root_list(struct dlm_ls *ls)
717 {
718         struct rb_node *n;
719         struct dlm_rsb *r;
720         int i, error = 0;
721
722         down_write(&ls->ls_root_sem);
723         if (!list_empty(&ls->ls_root_list)) {
724                 log_error(ls, "root list not empty");
725                 error = -EINVAL;
726                 goto out;
727         }
728
729         for (i = 0; i < ls->ls_rsbtbl_size; i++) {
730                 spin_lock(&ls->ls_rsbtbl[i].lock);
731                 for (n = rb_first(&ls->ls_rsbtbl[i].keep); n; n = rb_next(n)) {
732                         r = rb_entry(n, struct dlm_rsb, res_hashnode);
733                         list_add(&r->res_root_list, &ls->ls_root_list);
734                         dlm_hold_rsb(r);
735                 }
736
737                 /* If we're using a directory, add tossed rsbs to the root
738                    list; they'll have entries created in the new directory,
739                    but no other recovery steps should do anything with them. */
740
741                 if (dlm_no_directory(ls)) {
742                         spin_unlock(&ls->ls_rsbtbl[i].lock);
743                         continue;
744                 }
745
746                 for (n = rb_first(&ls->ls_rsbtbl[i].toss); n; n = rb_next(n)) {
747                         r = rb_entry(n, struct dlm_rsb, res_hashnode);
748                         list_add(&r->res_root_list, &ls->ls_root_list);
749                         dlm_hold_rsb(r);
750                 }
751                 spin_unlock(&ls->ls_rsbtbl[i].lock);
752         }
753  out:
754         up_write(&ls->ls_root_sem);
755         return error;
756 }
757
758 void dlm_release_root_list(struct dlm_ls *ls)
759 {
760         struct dlm_rsb *r, *safe;
761
762         down_write(&ls->ls_root_sem);
763         list_for_each_entry_safe(r, safe, &ls->ls_root_list, res_root_list) {
764                 list_del_init(&r->res_root_list);
765                 dlm_put_rsb(r);
766         }
767         up_write(&ls->ls_root_sem);
768 }
769
770 /* If not using a directory, clear the entire toss list, there's no benefit to
771    caching the master value since it's fixed.  If we are using a dir, keep the
772    rsb's we're the master of.  Recovery will add them to the root list and from
773    there they'll be entered in the rebuilt directory. */
774
775 void dlm_clear_toss_list(struct dlm_ls *ls)
776 {
777         struct rb_node *n, *next;
778         struct dlm_rsb *rsb;
779         int i;
780
781         for (i = 0; i < ls->ls_rsbtbl_size; i++) {
782                 spin_lock(&ls->ls_rsbtbl[i].lock);
783                 for (n = rb_first(&ls->ls_rsbtbl[i].toss); n; n = next) {
784                         next = rb_next(n);;
785                         rsb = rb_entry(n, struct dlm_rsb, res_hashnode);
786                         if (dlm_no_directory(ls) || !is_master(rsb)) {
787                                 rb_erase(n, &ls->ls_rsbtbl[i].toss);
788                                 dlm_free_rsb(rsb);
789                         }
790                 }
791                 spin_unlock(&ls->ls_rsbtbl[i].lock);
792         }
793 }
794