[DLM] add lock timeouts and warnings [2/6]
[linux-2.6.git] / fs / dlm / recoverd.c
1 /******************************************************************************
2 *******************************************************************************
3 **
4 **  Copyright (C) Sistina Software, Inc.  1997-2003  All rights reserved.
5 **  Copyright (C) 2004-2007 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 "member.h"
17 #include "dir.h"
18 #include "ast.h"
19 #include "recover.h"
20 #include "lowcomms.h"
21 #include "lock.h"
22 #include "requestqueue.h"
23 #include "recoverd.h"
24
25
26 /* If the start for which we're re-enabling locking (seq) has been superseded
27    by a newer stop (ls_recover_seq), we need to leave locking disabled. */
28
29 static int enable_locking(struct dlm_ls *ls, uint64_t seq)
30 {
31         int error = -EINTR;
32
33         spin_lock(&ls->ls_recover_lock);
34         if (ls->ls_recover_seq == seq) {
35                 set_bit(LSFL_RUNNING, &ls->ls_flags);
36                 up_write(&ls->ls_in_recovery);
37                 error = 0;
38         }
39         spin_unlock(&ls->ls_recover_lock);
40         return error;
41 }
42
43 static int ls_recover(struct dlm_ls *ls, struct dlm_recover *rv)
44 {
45         unsigned long start;
46         int error, neg = 0;
47
48         log_debug(ls, "recover %llx", (unsigned long long)rv->seq);
49
50         mutex_lock(&ls->ls_recoverd_active);
51
52         /*
53          * Suspending and resuming dlm_astd ensures that no lkb's from this ls
54          * will be processed by dlm_astd during recovery.
55          */
56
57         dlm_astd_suspend();
58         dlm_astd_resume();
59
60         /*
61          * This list of root rsb's will be the basis of most of the recovery
62          * routines.
63          */
64
65         dlm_create_root_list(ls);
66
67         /*
68          * Free all the tossed rsb's so we don't have to recover them.
69          */
70
71         dlm_clear_toss_list(ls);
72
73         /*
74          * Add or remove nodes from the lockspace's ls_nodes list.
75          * Also waits for all nodes to complete dlm_recover_members.
76          */
77
78         error = dlm_recover_members(ls, rv, &neg);
79         if (error) {
80                 log_debug(ls, "recover_members failed %d", error);
81                 goto fail;
82         }
83         start = jiffies;
84
85         /*
86          * Rebuild our own share of the directory by collecting from all other
87          * nodes their master rsb names that hash to us.
88          */
89
90         error = dlm_recover_directory(ls);
91         if (error) {
92                 log_debug(ls, "recover_directory failed %d", error);
93                 goto fail;
94         }
95
96         /*
97          * Wait for all nodes to complete directory rebuild.
98          */
99
100         error = dlm_recover_directory_wait(ls);
101         if (error) {
102                 log_debug(ls, "recover_directory_wait failed %d", error);
103                 goto fail;
104         }
105
106         /*
107          * We may have outstanding operations that are waiting for a reply from
108          * a failed node.  Mark these to be resent after recovery.  Unlock and
109          * cancel ops can just be completed.
110          */
111
112         dlm_recover_waiters_pre(ls);
113
114         error = dlm_recovery_stopped(ls);
115         if (error)
116                 goto fail;
117
118         if (neg || dlm_no_directory(ls)) {
119                 /*
120                  * Clear lkb's for departed nodes.
121                  */
122
123                 dlm_purge_locks(ls);
124
125                 /*
126                  * Get new master nodeid's for rsb's that were mastered on
127                  * departed nodes.
128                  */
129
130                 error = dlm_recover_masters(ls);
131                 if (error) {
132                         log_debug(ls, "recover_masters failed %d", error);
133                         goto fail;
134                 }
135
136                 /*
137                  * Send our locks on remastered rsb's to the new masters.
138                  */
139
140                 error = dlm_recover_locks(ls);
141                 if (error) {
142                         log_debug(ls, "recover_locks failed %d", error);
143                         goto fail;
144                 }
145
146                 error = dlm_recover_locks_wait(ls);
147                 if (error) {
148                         log_debug(ls, "recover_locks_wait failed %d", error);
149                         goto fail;
150                 }
151
152                 /*
153                  * Finalize state in master rsb's now that all locks can be
154                  * checked.  This includes conversion resolution and lvb
155                  * settings.
156                  */
157
158                 dlm_recover_rsbs(ls);
159         } else {
160                 /*
161                  * Other lockspace members may be going through the "neg" steps
162                  * while also adding us to the lockspace, in which case they'll
163                  * be doing the recover_locks (RS_LOCKS) barrier.
164                  */
165                 dlm_set_recover_status(ls, DLM_RS_LOCKS);
166
167                 error = dlm_recover_locks_wait(ls);
168                 if (error) {
169                         log_debug(ls, "recover_locks_wait failed %d", error);
170                         goto fail;
171                 }
172         }
173
174         dlm_release_root_list(ls);
175
176         /*
177          * Purge directory-related requests that are saved in requestqueue.
178          * All dir requests from before recovery are invalid now due to the dir
179          * rebuild and will be resent by the requesting nodes.
180          */
181
182         dlm_purge_requestqueue(ls);
183
184         dlm_set_recover_status(ls, DLM_RS_DONE);
185         error = dlm_recover_done_wait(ls);
186         if (error) {
187                 log_debug(ls, "recover_done_wait failed %d", error);
188                 goto fail;
189         }
190
191         dlm_clear_members_gone(ls);
192
193         dlm_adjust_timeouts(ls);
194
195         error = enable_locking(ls, rv->seq);
196         if (error) {
197                 log_debug(ls, "enable_locking failed %d", error);
198                 goto fail;
199         }
200
201         error = dlm_process_requestqueue(ls);
202         if (error) {
203                 log_debug(ls, "process_requestqueue failed %d", error);
204                 goto fail;
205         }
206
207         error = dlm_recover_waiters_post(ls);
208         if (error) {
209                 log_debug(ls, "recover_waiters_post failed %d", error);
210                 goto fail;
211         }
212
213         dlm_grant_after_purge(ls);
214
215         dlm_astd_wake();
216
217         log_debug(ls, "recover %llx done: %u ms",
218                   (unsigned long long)rv->seq,
219                   jiffies_to_msecs(jiffies - start));
220         mutex_unlock(&ls->ls_recoverd_active);
221
222         return 0;
223
224  fail:
225         dlm_release_root_list(ls);
226         log_debug(ls, "recover %llx error %d",
227                   (unsigned long long)rv->seq, error);
228         mutex_unlock(&ls->ls_recoverd_active);
229         return error;
230 }
231
232 /* The dlm_ls_start() that created the rv we take here may already have been
233    stopped via dlm_ls_stop(); in that case we need to leave the RECOVERY_STOP
234    flag set. */
235
236 static void do_ls_recovery(struct dlm_ls *ls)
237 {
238         struct dlm_recover *rv = NULL;
239
240         spin_lock(&ls->ls_recover_lock);
241         rv = ls->ls_recover_args;
242         ls->ls_recover_args = NULL;
243         if (rv && ls->ls_recover_seq == rv->seq)
244                 clear_bit(LSFL_RECOVERY_STOP, &ls->ls_flags);
245         spin_unlock(&ls->ls_recover_lock);
246
247         if (rv) {
248                 ls_recover(ls, rv);
249                 kfree(rv->nodeids);
250                 kfree(rv);
251         }
252 }
253
254 static int dlm_recoverd(void *arg)
255 {
256         struct dlm_ls *ls;
257
258         ls = dlm_find_lockspace_local(arg);
259         if (!ls) {
260                 log_print("dlm_recoverd: no lockspace %p", arg);
261                 return -1;
262         }
263
264         while (!kthread_should_stop()) {
265                 set_current_state(TASK_INTERRUPTIBLE);
266                 if (!test_bit(LSFL_WORK, &ls->ls_flags))
267                         schedule();
268                 set_current_state(TASK_RUNNING);
269
270                 if (test_and_clear_bit(LSFL_WORK, &ls->ls_flags))
271                         do_ls_recovery(ls);
272         }
273
274         dlm_put_lockspace(ls);
275         return 0;
276 }
277
278 void dlm_recoverd_kick(struct dlm_ls *ls)
279 {
280         set_bit(LSFL_WORK, &ls->ls_flags);
281         wake_up_process(ls->ls_recoverd_task);
282 }
283
284 int dlm_recoverd_start(struct dlm_ls *ls)
285 {
286         struct task_struct *p;
287         int error = 0;
288
289         p = kthread_run(dlm_recoverd, ls, "dlm_recoverd");
290         if (IS_ERR(p))
291                 error = PTR_ERR(p);
292         else
293                 ls->ls_recoverd_task = p;
294         return error;
295 }
296
297 void dlm_recoverd_stop(struct dlm_ls *ls)
298 {
299         kthread_stop(ls->ls_recoverd_task);
300 }
301
302 void dlm_recoverd_suspend(struct dlm_ls *ls)
303 {
304         wake_up(&ls->ls_wait_general);
305         mutex_lock(&ls->ls_recoverd_active);
306 }
307
308 void dlm_recoverd_resume(struct dlm_ls *ls)
309 {
310         mutex_unlock(&ls->ls_recoverd_active);
311 }
312