[DCCP] ccid3: Fix bug in calculation of first t_nom and first t_ipi
[linux-2.6/mini2440.git] / fs / dlm / recover.c
bloba5e6d184872e0576301b72acb2f765aba3bac24e
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.
11 *******************************************************************************
12 ******************************************************************************/
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"
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).
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.
44 static void dlm_wait_timer_fn(unsigned long data)
46 struct dlm_ls *ls = (struct dlm_ls *) data;
47 mod_timer(&ls->ls_timer, jiffies + (dlm_config.recover_timer * HZ));
48 wake_up(&ls->ls_wait_general);
51 int dlm_wait_function(struct dlm_ls *ls, int (*testfn) (struct dlm_ls *ls))
53 int error = 0;
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.recover_timer * HZ);
59 add_timer(&ls->ls_timer);
61 wait_event(ls->ls_wait_general, testfn(ls) || dlm_recovery_stopped(ls));
62 del_timer_sync(&ls->ls_timer);
64 if (dlm_recovery_stopped(ls)) {
65 log_debug(ls, "dlm_wait_function aborted");
66 error = -EINTR;
68 return error;
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.
79 uint32_t dlm_recover_status(struct dlm_ls *ls)
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;
88 void dlm_set_recover_status(struct dlm_ls *ls, uint32_t status)
90 spin_lock(&ls->ls_recover_lock);
91 ls->ls_recover_status |= status;
92 spin_unlock(&ls->ls_recover_lock);
95 static int wait_status_all(struct dlm_ls *ls, uint32_t wait_status)
97 struct dlm_rcom *rc = (struct dlm_rcom *) ls->ls_recover_buf;
98 struct dlm_member *memb;
99 int error = 0, delay;
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;
109 error = dlm_rcom_status(ls, memb->nodeid);
110 if (error)
111 goto out;
113 if (rc->rc_result & wait_status)
114 break;
115 if (delay < 1000)
116 delay += 20;
117 msleep(delay);
120 out:
121 return error;
124 static int wait_status_low(struct dlm_ls *ls, uint32_t wait_status)
126 struct dlm_rcom *rc = (struct dlm_rcom *) ls->ls_recover_buf;
127 int error = 0, delay = 0, nodeid = ls->ls_low_nodeid;
129 for (;;) {
130 if (dlm_recovery_stopped(ls)) {
131 error = -EINTR;
132 goto out;
135 error = dlm_rcom_status(ls, nodeid);
136 if (error)
137 break;
139 if (rc->rc_result & wait_status)
140 break;
141 if (delay < 1000)
142 delay += 20;
143 msleep(delay);
145 out:
146 return error;
149 static int wait_status(struct dlm_ls *ls, uint32_t status)
151 uint32_t status_all = status << 1;
152 int error;
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);
161 return error;
164 int dlm_recover_members_wait(struct dlm_ls *ls)
166 return wait_status(ls, DLM_RS_NODES);
169 int dlm_recover_directory_wait(struct dlm_ls *ls)
171 return wait_status(ls, DLM_RS_DIR);
174 int dlm_recover_locks_wait(struct dlm_ls *ls)
176 return wait_status(ls, DLM_RS_LOCKS);
179 int dlm_recover_done_wait(struct dlm_ls *ls)
181 return wait_status(ls, DLM_RS_DONE);
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.
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.
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.
196 static int recover_list_empty(struct dlm_ls *ls)
198 int empty;
200 spin_lock(&ls->ls_recover_list_lock);
201 empty = list_empty(&ls->ls_recover_list);
202 spin_unlock(&ls->ls_recover_list_lock);
204 return empty;
207 static void recover_list_add(struct dlm_rsb *r)
209 struct dlm_ls *ls = r->res_ls;
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);
217 spin_unlock(&ls->ls_recover_list_lock);
220 static void recover_list_del(struct dlm_rsb *r)
222 struct dlm_ls *ls = r->res_ls;
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);
229 dlm_put_rsb(r);
232 static struct dlm_rsb *recover_list_find(struct dlm_ls *ls, uint64_t id)
234 struct dlm_rsb *r = NULL;
236 spin_lock(&ls->ls_recover_list_lock);
238 list_for_each_entry(r, &ls->ls_recover_list, res_recover_list) {
239 if (id == (unsigned long) r)
240 goto out;
242 r = NULL;
243 out:
244 spin_unlock(&ls->ls_recover_list_lock);
245 return r;
248 static void recover_list_clear(struct dlm_ls *ls)
250 struct dlm_rsb *r, *s;
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 dlm_put_rsb(r);
256 ls->ls_recover_list_count--;
259 if (ls->ls_recover_list_count != 0) {
260 log_error(ls, "warning: recover_list_count %d",
261 ls->ls_recover_list_count);
262 ls->ls_recover_list_count = 0;
264 spin_unlock(&ls->ls_recover_list_lock);
268 /* Master recovery: find new master node for rsb's that were
269 mastered on nodes that have been removed.
271 dlm_recover_masters
272 recover_master
273 dlm_send_rcom_lookup -> receive_rcom_lookup
274 dlm_dir_lookup
275 receive_rcom_lookup_reply <-
276 dlm_recover_master_reply
277 set_new_master
278 set_master_lkbs
279 set_lock_master
283 * Set the lock master for all LKBs in a lock queue
284 * If we are the new master of the rsb, we may have received new
285 * MSTCPY locks from other nodes already which we need to ignore
286 * when setting the new nodeid.
289 static void set_lock_master(struct list_head *queue, int nodeid)
291 struct dlm_lkb *lkb;
293 list_for_each_entry(lkb, queue, lkb_statequeue)
294 if (!(lkb->lkb_flags & DLM_IFL_MSTCPY))
295 lkb->lkb_nodeid = nodeid;
298 static void set_master_lkbs(struct dlm_rsb *r)
300 set_lock_master(&r->res_grantqueue, r->res_nodeid);
301 set_lock_master(&r->res_convertqueue, r->res_nodeid);
302 set_lock_master(&r->res_waitqueue, r->res_nodeid);
306 * Propogate the new master nodeid to locks
307 * The NEW_MASTER flag tells dlm_recover_locks() which rsb's to consider.
308 * The NEW_MASTER2 flag tells recover_lvb() and set_locks_purged() which
309 * rsb's to consider.
312 static void set_new_master(struct dlm_rsb *r, int nodeid)
314 lock_rsb(r);
315 r->res_nodeid = nodeid;
316 set_master_lkbs(r);
317 rsb_set_flag(r, RSB_NEW_MASTER);
318 rsb_set_flag(r, RSB_NEW_MASTER2);
319 unlock_rsb(r);
323 * We do async lookups on rsb's that need new masters. The rsb's
324 * waiting for a lookup reply are kept on the recover_list.
327 static int recover_master(struct dlm_rsb *r)
329 struct dlm_ls *ls = r->res_ls;
330 int error, dir_nodeid, ret_nodeid, our_nodeid = dlm_our_nodeid();
332 dir_nodeid = dlm_dir_nodeid(r);
334 if (dir_nodeid == our_nodeid) {
335 error = dlm_dir_lookup(ls, our_nodeid, r->res_name,
336 r->res_length, &ret_nodeid);
337 if (error)
338 log_error(ls, "recover dir lookup error %d", error);
340 if (ret_nodeid == our_nodeid)
341 ret_nodeid = 0;
342 set_new_master(r, ret_nodeid);
343 } else {
344 recover_list_add(r);
345 error = dlm_send_rcom_lookup(r, dir_nodeid);
348 return error;
352 * When not using a directory, most resource names will hash to a new static
353 * master nodeid and the resource will need to be remastered.
356 static int recover_master_static(struct dlm_rsb *r)
358 int master = dlm_dir_nodeid(r);
360 if (master == dlm_our_nodeid())
361 master = 0;
363 if (r->res_nodeid != master) {
364 if (is_master(r))
365 dlm_purge_mstcpy_locks(r);
366 set_new_master(r, master);
367 return 1;
369 return 0;
373 * Go through local root resources and for each rsb which has a master which
374 * has departed, get the new master nodeid from the directory. The dir will
375 * assign mastery to the first node to look up the new master. That means
376 * we'll discover in this lookup if we're the new master of any rsb's.
378 * We fire off all the dir lookup requests individually and asynchronously to
379 * the correct dir node.
382 int dlm_recover_masters(struct dlm_ls *ls)
384 struct dlm_rsb *r;
385 int error = 0, count = 0;
387 log_debug(ls, "dlm_recover_masters");
389 down_read(&ls->ls_root_sem);
390 list_for_each_entry(r, &ls->ls_root_list, res_root_list) {
391 if (dlm_recovery_stopped(ls)) {
392 up_read(&ls->ls_root_sem);
393 error = -EINTR;
394 goto out;
397 if (dlm_no_directory(ls))
398 count += recover_master_static(r);
399 else if (!is_master(r) && dlm_is_removed(ls, r->res_nodeid)) {
400 recover_master(r);
401 count++;
404 schedule();
406 up_read(&ls->ls_root_sem);
408 log_debug(ls, "dlm_recover_masters %d resources", count);
410 error = dlm_wait_function(ls, &recover_list_empty);
411 out:
412 if (error)
413 recover_list_clear(ls);
414 return error;
417 int dlm_recover_master_reply(struct dlm_ls *ls, struct dlm_rcom *rc)
419 struct dlm_rsb *r;
420 int nodeid;
422 r = recover_list_find(ls, rc->rc_id);
423 if (!r) {
424 log_error(ls, "dlm_recover_master_reply no id %llx",
425 (unsigned long long)rc->rc_id);
426 goto out;
429 nodeid = rc->rc_result;
430 if (nodeid == dlm_our_nodeid())
431 nodeid = 0;
433 set_new_master(r, nodeid);
434 recover_list_del(r);
436 if (recover_list_empty(ls))
437 wake_up(&ls->ls_wait_general);
438 out:
439 return 0;
443 /* Lock recovery: rebuild the process-copy locks we hold on a
444 remastered rsb on the new rsb master.
446 dlm_recover_locks
447 recover_locks
448 recover_locks_queue
449 dlm_send_rcom_lock -> receive_rcom_lock
450 dlm_recover_master_copy
451 receive_rcom_lock_reply <-
452 dlm_recover_process_copy
457 * keep a count of the number of lkb's we send to the new master; when we get
458 * an equal number of replies then recovery for the rsb is done
461 static int recover_locks_queue(struct dlm_rsb *r, struct list_head *head)
463 struct dlm_lkb *lkb;
464 int error = 0;
466 list_for_each_entry(lkb, head, lkb_statequeue) {
467 error = dlm_send_rcom_lock(r, lkb);
468 if (error)
469 break;
470 r->res_recover_locks_count++;
473 return error;
476 static int recover_locks(struct dlm_rsb *r)
478 int error = 0;
480 lock_rsb(r);
482 DLM_ASSERT(!r->res_recover_locks_count, dlm_dump_rsb(r););
484 error = recover_locks_queue(r, &r->res_grantqueue);
485 if (error)
486 goto out;
487 error = recover_locks_queue(r, &r->res_convertqueue);
488 if (error)
489 goto out;
490 error = recover_locks_queue(r, &r->res_waitqueue);
491 if (error)
492 goto out;
494 if (r->res_recover_locks_count)
495 recover_list_add(r);
496 else
497 rsb_clear_flag(r, RSB_NEW_MASTER);
498 out:
499 unlock_rsb(r);
500 return error;
503 int dlm_recover_locks(struct dlm_ls *ls)
505 struct dlm_rsb *r;
506 int error, count = 0;
508 log_debug(ls, "dlm_recover_locks");
510 down_read(&ls->ls_root_sem);
511 list_for_each_entry(r, &ls->ls_root_list, res_root_list) {
512 if (is_master(r)) {
513 rsb_clear_flag(r, RSB_NEW_MASTER);
514 continue;
517 if (!rsb_flag(r, RSB_NEW_MASTER))
518 continue;
520 if (dlm_recovery_stopped(ls)) {
521 error = -EINTR;
522 up_read(&ls->ls_root_sem);
523 goto out;
526 error = recover_locks(r);
527 if (error) {
528 up_read(&ls->ls_root_sem);
529 goto out;
532 count += r->res_recover_locks_count;
534 up_read(&ls->ls_root_sem);
536 log_debug(ls, "dlm_recover_locks %d locks", count);
538 error = dlm_wait_function(ls, &recover_list_empty);
539 out:
540 if (error)
541 recover_list_clear(ls);
542 else
543 dlm_set_recover_status(ls, DLM_RS_LOCKS);
544 return error;
547 void dlm_recovered_lock(struct dlm_rsb *r)
549 DLM_ASSERT(rsb_flag(r, RSB_NEW_MASTER), dlm_dump_rsb(r););
551 r->res_recover_locks_count--;
552 if (!r->res_recover_locks_count) {
553 rsb_clear_flag(r, RSB_NEW_MASTER);
554 recover_list_del(r);
557 if (recover_list_empty(r->res_ls))
558 wake_up(&r->res_ls->ls_wait_general);
562 * The lvb needs to be recovered on all master rsb's. This includes setting
563 * the VALNOTVALID flag if necessary, and determining the correct lvb contents
564 * based on the lvb's of the locks held on the rsb.
566 * RSB_VALNOTVALID is set if there are only NL/CR locks on the rsb. If it
567 * was already set prior to recovery, it's not cleared, regardless of locks.
569 * The LVB contents are only considered for changing when this is a new master
570 * of the rsb (NEW_MASTER2). Then, the rsb's lvb is taken from any lkb with
571 * mode > CR. If no lkb's exist with mode above CR, the lvb contents are taken
572 * from the lkb with the largest lvb sequence number.
575 static void recover_lvb(struct dlm_rsb *r)
577 struct dlm_lkb *lkb, *high_lkb = NULL;
578 uint32_t high_seq = 0;
579 int lock_lvb_exists = 0;
580 int big_lock_exists = 0;
581 int lvblen = r->res_ls->ls_lvblen;
583 list_for_each_entry(lkb, &r->res_grantqueue, lkb_statequeue) {
584 if (!(lkb->lkb_exflags & DLM_LKF_VALBLK))
585 continue;
587 lock_lvb_exists = 1;
589 if (lkb->lkb_grmode > DLM_LOCK_CR) {
590 big_lock_exists = 1;
591 goto setflag;
594 if (((int)lkb->lkb_lvbseq - (int)high_seq) >= 0) {
595 high_lkb = lkb;
596 high_seq = lkb->lkb_lvbseq;
600 list_for_each_entry(lkb, &r->res_convertqueue, lkb_statequeue) {
601 if (!(lkb->lkb_exflags & DLM_LKF_VALBLK))
602 continue;
604 lock_lvb_exists = 1;
606 if (lkb->lkb_grmode > DLM_LOCK_CR) {
607 big_lock_exists = 1;
608 goto setflag;
611 if (((int)lkb->lkb_lvbseq - (int)high_seq) >= 0) {
612 high_lkb = lkb;
613 high_seq = lkb->lkb_lvbseq;
617 setflag:
618 if (!lock_lvb_exists)
619 goto out;
621 if (!big_lock_exists)
622 rsb_set_flag(r, RSB_VALNOTVALID);
624 /* don't mess with the lvb unless we're the new master */
625 if (!rsb_flag(r, RSB_NEW_MASTER2))
626 goto out;
628 if (!r->res_lvbptr) {
629 r->res_lvbptr = allocate_lvb(r->res_ls);
630 if (!r->res_lvbptr)
631 goto out;
634 if (big_lock_exists) {
635 r->res_lvbseq = lkb->lkb_lvbseq;
636 memcpy(r->res_lvbptr, lkb->lkb_lvbptr, lvblen);
637 } else if (high_lkb) {
638 r->res_lvbseq = high_lkb->lkb_lvbseq;
639 memcpy(r->res_lvbptr, high_lkb->lkb_lvbptr, lvblen);
640 } else {
641 r->res_lvbseq = 0;
642 memset(r->res_lvbptr, 0, lvblen);
644 out:
645 return;
648 /* All master rsb's flagged RECOVER_CONVERT need to be looked at. The locks
649 converting PR->CW or CW->PR need to have their lkb_grmode set. */
651 static void recover_conversion(struct dlm_rsb *r)
653 struct dlm_lkb *lkb;
654 int grmode = -1;
656 list_for_each_entry(lkb, &r->res_grantqueue, lkb_statequeue) {
657 if (lkb->lkb_grmode == DLM_LOCK_PR ||
658 lkb->lkb_grmode == DLM_LOCK_CW) {
659 grmode = lkb->lkb_grmode;
660 break;
664 list_for_each_entry(lkb, &r->res_convertqueue, lkb_statequeue) {
665 if (lkb->lkb_grmode != DLM_LOCK_IV)
666 continue;
667 if (grmode == -1)
668 lkb->lkb_grmode = lkb->lkb_rqmode;
669 else
670 lkb->lkb_grmode = grmode;
674 /* We've become the new master for this rsb and waiting/converting locks may
675 need to be granted in dlm_grant_after_purge() due to locks that may have
676 existed from a removed node. */
678 static void set_locks_purged(struct dlm_rsb *r)
680 if (!list_empty(&r->res_waitqueue) || !list_empty(&r->res_convertqueue))
681 rsb_set_flag(r, RSB_LOCKS_PURGED);
684 void dlm_recover_rsbs(struct dlm_ls *ls)
686 struct dlm_rsb *r;
687 int count = 0;
689 log_debug(ls, "dlm_recover_rsbs");
691 down_read(&ls->ls_root_sem);
692 list_for_each_entry(r, &ls->ls_root_list, res_root_list) {
693 lock_rsb(r);
694 if (is_master(r)) {
695 if (rsb_flag(r, RSB_RECOVER_CONVERT))
696 recover_conversion(r);
697 if (rsb_flag(r, RSB_NEW_MASTER2))
698 set_locks_purged(r);
699 recover_lvb(r);
700 count++;
702 rsb_clear_flag(r, RSB_RECOVER_CONVERT);
703 rsb_clear_flag(r, RSB_NEW_MASTER2);
704 unlock_rsb(r);
706 up_read(&ls->ls_root_sem);
708 log_debug(ls, "dlm_recover_rsbs %d rsbs", count);
711 /* Create a single list of all root rsb's to be used during recovery */
713 int dlm_create_root_list(struct dlm_ls *ls)
715 struct dlm_rsb *r;
716 int i, error = 0;
718 down_write(&ls->ls_root_sem);
719 if (!list_empty(&ls->ls_root_list)) {
720 log_error(ls, "root list not empty");
721 error = -EINVAL;
722 goto out;
725 for (i = 0; i < ls->ls_rsbtbl_size; i++) {
726 read_lock(&ls->ls_rsbtbl[i].lock);
727 list_for_each_entry(r, &ls->ls_rsbtbl[i].list, res_hashchain) {
728 list_add(&r->res_root_list, &ls->ls_root_list);
729 dlm_hold_rsb(r);
731 read_unlock(&ls->ls_rsbtbl[i].lock);
733 out:
734 up_write(&ls->ls_root_sem);
735 return error;
738 void dlm_release_root_list(struct dlm_ls *ls)
740 struct dlm_rsb *r, *safe;
742 down_write(&ls->ls_root_sem);
743 list_for_each_entry_safe(r, safe, &ls->ls_root_list, res_root_list) {
744 list_del_init(&r->res_root_list);
745 dlm_put_rsb(r);
747 up_write(&ls->ls_root_sem);
750 void dlm_clear_toss_list(struct dlm_ls *ls)
752 struct dlm_rsb *r, *safe;
753 int i;
755 for (i = 0; i < ls->ls_rsbtbl_size; i++) {
756 write_lock(&ls->ls_rsbtbl[i].lock);
757 list_for_each_entry_safe(r, safe, &ls->ls_rsbtbl[i].toss,
758 res_hashchain) {
759 list_del(&r->res_hashchain);
760 free_rsb(r);
762 write_unlock(&ls->ls_rsbtbl[i].lock);