[DLM] The core of the DLM for GFS2/CLVM
[linux-3.10.git] / fs / dlm / recoverd.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 "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26 /* If the start for which we're re-enabling locking (seq) has been superseded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 %"PRIx64"", rv->seq);
49
50         down(&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_error(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_error(ls, "recover_directory failed %d", error);
93                 goto fail;
94         }
95
96         /*
97          * Purge directory-related requests that are saved in requestqueue.
98          * All dir requests from before recovery are invalid now due to the dir
99          * rebuild and will be resent by the requesting nodes.
100          */
101
102         dlm_purge_requestqueue(ls);
103
104         /*
105          * Wait for all nodes to complete directory rebuild.
106          */
107
108         error = dlm_recover_directory_wait(ls);
109         if (error) {
110                 log_error(ls, "recover_directory_wait failed %d", error);
111                 goto fail;
112         }
113
114         /*
115          * We may have outstanding operations that are waiting for a reply from
116          * a failed node.  Mark these to be resent after recovery.  Unlock and
117          * cancel ops can just be completed.
118          */
119
120         dlm_recover_waiters_pre(ls);
121
122         error = dlm_recovery_stopped(ls);
123         if (error)
124                 goto fail;
125
126         if (neg || dlm_no_directory(ls)) {
127                 /*
128                  * Clear lkb's for departed nodes.
129                  */
130
131                 dlm_purge_locks(ls);
132
133                 /*
134                  * Get new master nodeid's for rsb's that were mastered on
135                  * departed nodes.
136                  */
137
138                 error = dlm_recover_masters(ls);
139                 if (error) {
140                         log_error(ls, "recover_masters failed %d", error);
141                         goto fail;
142                 }
143
144                 /*
145                  * Send our locks on remastered rsb's to the new masters.
146                  */
147
148                 error = dlm_recover_locks(ls);
149                 if (error) {
150                         log_error(ls, "recover_locks failed %d", error);
151                         goto fail;
152                 }
153
154                 error = dlm_recover_locks_wait(ls);
155                 if (error) {
156                         log_error(ls, "recover_locks_wait failed %d", error);
157                         goto fail;
158                 }
159
160                 /*
161                  * Finalize state in master rsb's now that all locks can be
162                  * checked.  This includes conversion resolution and lvb
163                  * settings.
164                  */
165
166                 dlm_recover_rsbs(ls);
167         }
168
169         dlm_release_root_list(ls);
170
171         dlm_set_recover_status(ls, DLM_RS_DONE);
172         error = dlm_recover_done_wait(ls);
173         if (error) {
174                 log_error(ls, "recover_done_wait failed %d", error);
175                 goto fail;
176         }
177
178         dlm_clear_members_gone(ls);
179
180         error = enable_locking(ls, rv->seq);
181         if (error) {
182                 log_error(ls, "enable_locking failed %d", error);
183                 goto fail;
184         }
185
186         error = dlm_process_requestqueue(ls);
187         if (error) {
188                 log_error(ls, "process_requestqueue failed %d", error);
189                 goto fail;
190         }
191
192         error = dlm_recover_waiters_post(ls);
193         if (error) {
194                 log_error(ls, "recover_waiters_post failed %d", error);
195                 goto fail;
196         }
197
198         dlm_grant_after_purge(ls);
199
200         dlm_astd_wake();
201
202         log_debug(ls, "recover %"PRIx64" done: %u ms", rv->seq,
203                   jiffies_to_msecs(jiffies - start));
204         up(&ls->ls_recoverd_active);
205
206         return 0;
207
208  fail:
209         dlm_release_root_list(ls);
210         log_debug(ls, "recover %"PRIx64" error %d", rv->seq, error);
211         up(&ls->ls_recoverd_active);
212         return error;
213 }
214
215 static void do_ls_recovery(struct dlm_ls *ls)
216 {
217         struct dlm_recover *rv = NULL;
218
219         spin_lock(&ls->ls_recover_lock);
220         rv = ls->ls_recover_args;
221         ls->ls_recover_args = NULL;
222         clear_bit(LSFL_RECOVERY_STOP, &ls->ls_flags);
223         spin_unlock(&ls->ls_recover_lock);
224
225         if (rv) {
226                 ls_recover(ls, rv);
227                 kfree(rv->nodeids);
228                 kfree(rv);
229         }
230 }
231
232 static int dlm_recoverd(void *arg)
233 {
234         struct dlm_ls *ls;
235
236         ls = dlm_find_lockspace_local(arg);
237
238         while (!kthread_should_stop()) {
239                 set_current_state(TASK_INTERRUPTIBLE);
240                 if (!test_bit(LSFL_WORK, &ls->ls_flags))
241                         schedule();
242                 set_current_state(TASK_RUNNING);
243
244                 if (test_and_clear_bit(LSFL_WORK, &ls->ls_flags))
245                         do_ls_recovery(ls);
246         }
247
248         dlm_put_lockspace(ls);
249         return 0;
250 }
251
252 void dlm_recoverd_kick(struct dlm_ls *ls)
253 {
254         set_bit(LSFL_WORK, &ls->ls_flags);
255         wake_up_process(ls->ls_recoverd_task);
256 }
257
258 int dlm_recoverd_start(struct dlm_ls *ls)
259 {
260         struct task_struct *p;
261         int error = 0;
262
263         p = kthread_run(dlm_recoverd, ls, "dlm_recoverd");
264         if (IS_ERR(p))
265                 error = PTR_ERR(p);
266         else
267                 ls->ls_recoverd_task = p;
268         return error;
269 }
270
271 void dlm_recoverd_stop(struct dlm_ls *ls)
272 {
273         kthread_stop(ls->ls_recoverd_task);
274 }
275
276 void dlm_recoverd_suspend(struct dlm_ls *ls)
277 {
278         down(&ls->ls_recoverd_active);
279 }
280
281 void dlm_recoverd_resume(struct dlm_ls *ls)
282 {
283         up(&ls->ls_recoverd_active);
284 }
285