1 // SPDX-License-Identifier: GPL-2.0-only
2 /******************************************************************************
3 *******************************************************************************
4 **
5 ** Copyright (C) Sistina Software, Inc. 1997-2003 All rights reserved.
6 ** Copyright (C) 2004-2011 Red Hat, Inc. All rights reserved.
7 **
8 **
9 *******************************************************************************
10 ******************************************************************************/
11
12 #include "dlm_internal.h"
13 #include "lockspace.h"
14 #include "member.h"
15 #include "dir.h"
16 #include "ast.h"
17 #include "recover.h"
18 #include "lowcomms.h"
19 #include "lock.h"
20 #include "requestqueue.h"
21 #include "recoverd.h"
22
23
24 /* If the start for which we're re-enabling locking (seq) has been superseded
25 by a newer stop (ls_recover_seq), we need to leave locking disabled.
26
27 We suspend dlm_recv threads here to avoid the race where dlm_recv a) sees
28 locking stopped and b) adds a message to the requestqueue, but dlm_recoverd
29 enables locking and clears the requestqueue between a and b. */
30
enable_locking(struct dlm_ls * ls,uint64_t seq)31 static int enable_locking(struct dlm_ls *ls, uint64_t seq)
32 {
33 int error = -EINTR;
34
35 down_write(&ls->ls_recv_active);
36
37 spin_lock(&ls->ls_recover_lock);
38 if (ls->ls_recover_seq == seq) {
39 set_bit(LSFL_RUNNING, &ls->ls_flags);
40 /* unblocks processes waiting to enter the dlm */
41 up_write(&ls->ls_in_recovery);
42 clear_bit(LSFL_RECOVER_LOCK, &ls->ls_flags);
43 error = 0;
44 }
45 spin_unlock(&ls->ls_recover_lock);
46
47 up_write(&ls->ls_recv_active);
48 return error;
49 }
50
ls_recover(struct dlm_ls * ls,struct dlm_recover * rv)51 static int ls_recover(struct dlm_ls *ls, struct dlm_recover *rv)
52 {
53 unsigned long start;
54 int error, neg = 0;
55
56 log_rinfo(ls, "dlm_recover %llu", (unsigned long long)rv->seq);
57
58 mutex_lock(&ls->ls_recoverd_active);
59
60 dlm_callback_suspend(ls);
61
62 dlm_clear_toss(ls);
63
64 /*
65 * This list of root rsb's will be the basis of most of the recovery
66 * routines.
67 */
68
69 dlm_create_root_list(ls);
70
71 /*
72 * Add or remove nodes from the lockspace's ls_nodes list.
73 */
74
75 error = dlm_recover_members(ls, rv, &neg);
76 if (error) {
77 log_rinfo(ls, "dlm_recover_members error %d", error);
78 goto fail;
79 }
80
81 dlm_recover_dir_nodeid(ls);
82
83 ls->ls_recover_dir_sent_res = 0;
84 ls->ls_recover_dir_sent_msg = 0;
85 ls->ls_recover_locks_in = 0;
86
87 dlm_set_recover_status(ls, DLM_RS_NODES);
88
89 error = dlm_recover_members_wait(ls);
90 if (error) {
91 log_rinfo(ls, "dlm_recover_members_wait error %d", error);
92 goto fail;
93 }
94
95 start = jiffies;
96
97 /*
98 * Rebuild our own share of the directory by collecting from all other
99 * nodes their master rsb names that hash to us.
100 */
101
102 error = dlm_recover_directory(ls);
103 if (error) {
104 log_rinfo(ls, "dlm_recover_directory error %d", error);
105 goto fail;
106 }
107
108 dlm_set_recover_status(ls, DLM_RS_DIR);
109
110 error = dlm_recover_directory_wait(ls);
111 if (error) {
112 log_rinfo(ls, "dlm_recover_directory_wait error %d", error);
113 goto fail;
114 }
115
116 log_rinfo(ls, "dlm_recover_directory %u out %u messages",
117 ls->ls_recover_dir_sent_res, ls->ls_recover_dir_sent_msg);
118
119 /*
120 * We may have outstanding operations that are waiting for a reply from
121 * a failed node. Mark these to be resent after recovery. Unlock and
122 * cancel ops can just be completed.
123 */
124
125 dlm_recover_waiters_pre(ls);
126
127 error = dlm_recovery_stopped(ls);
128 if (error)
129 goto fail;
130
131 if (neg || dlm_no_directory(ls)) {
132 /*
133 * Clear lkb's for departed nodes.
134 */
135
136 dlm_recover_purge(ls);
137
138 /*
139 * Get new master nodeid's for rsb's that were mastered on
140 * departed nodes.
141 */
142
143 error = dlm_recover_masters(ls);
144 if (error) {
145 log_rinfo(ls, "dlm_recover_masters error %d", error);
146 goto fail;
147 }
148
149 /*
150 * Send our locks on remastered rsb's to the new masters.
151 */
152
153 error = dlm_recover_locks(ls);
154 if (error) {
155 log_rinfo(ls, "dlm_recover_locks error %d", error);
156 goto fail;
157 }
158
159 dlm_set_recover_status(ls, DLM_RS_LOCKS);
160
161 error = dlm_recover_locks_wait(ls);
162 if (error) {
163 log_rinfo(ls, "dlm_recover_locks_wait error %d", error);
164 goto fail;
165 }
166
167 log_rinfo(ls, "dlm_recover_locks %u in",
168 ls->ls_recover_locks_in);
169
170 /*
171 * Finalize state in master rsb's now that all locks can be
172 * checked. This includes conversion resolution and lvb
173 * settings.
174 */
175
176 dlm_recover_rsbs(ls);
177 } else {
178 /*
179 * Other lockspace members may be going through the "neg" steps
180 * while also adding us to the lockspace, in which case they'll
181 * be doing the recover_locks (RS_LOCKS) barrier.
182 */
183 dlm_set_recover_status(ls, DLM_RS_LOCKS);
184
185 error = dlm_recover_locks_wait(ls);
186 if (error) {
187 log_rinfo(ls, "dlm_recover_locks_wait error %d", error);
188 goto fail;
189 }
190 }
191
192 dlm_release_root_list(ls);
193
194 /*
195 * Purge directory-related requests that are saved in requestqueue.
196 * All dir requests from before recovery are invalid now due to the dir
197 * rebuild and will be resent by the requesting nodes.
198 */
199
200 dlm_purge_requestqueue(ls);
201
202 dlm_set_recover_status(ls, DLM_RS_DONE);
203
204 error = dlm_recover_done_wait(ls);
205 if (error) {
206 log_rinfo(ls, "dlm_recover_done_wait error %d", error);
207 goto fail;
208 }
209
210 dlm_clear_members_gone(ls);
211
212 dlm_adjust_timeouts(ls);
213
214 dlm_callback_resume(ls);
215
216 error = enable_locking(ls, rv->seq);
217 if (error) {
218 log_rinfo(ls, "enable_locking error %d", error);
219 goto fail;
220 }
221
222 error = dlm_process_requestqueue(ls);
223 if (error) {
224 log_rinfo(ls, "dlm_process_requestqueue error %d", error);
225 goto fail;
226 }
227
228 error = dlm_recover_waiters_post(ls);
229 if (error) {
230 log_rinfo(ls, "dlm_recover_waiters_post error %d", error);
231 goto fail;
232 }
233
234 dlm_recover_grant(ls);
235
236 log_rinfo(ls, "dlm_recover %llu generation %u done: %u ms",
237 (unsigned long long)rv->seq, ls->ls_generation,
238 jiffies_to_msecs(jiffies - start));
239 mutex_unlock(&ls->ls_recoverd_active);
240
241 dlm_lsop_recover_done(ls);
242 return 0;
243
244 fail:
245 dlm_release_root_list(ls);
246 log_rinfo(ls, "dlm_recover %llu error %d",
247 (unsigned long long)rv->seq, error);
248 mutex_unlock(&ls->ls_recoverd_active);
249 return error;
250 }
251
252 /* The dlm_ls_start() that created the rv we take here may already have been
253 stopped via dlm_ls_stop(); in that case we need to leave the RECOVERY_STOP
254 flag set. */
255
do_ls_recovery(struct dlm_ls * ls)256 static void do_ls_recovery(struct dlm_ls *ls)
257 {
258 struct dlm_recover *rv = NULL;
259
260 spin_lock(&ls->ls_recover_lock);
261 rv = ls->ls_recover_args;
262 ls->ls_recover_args = NULL;
263 if (rv && ls->ls_recover_seq == rv->seq)
264 clear_bit(LSFL_RECOVER_STOP, &ls->ls_flags);
265 spin_unlock(&ls->ls_recover_lock);
266
267 if (rv) {
268 ls_recover(ls, rv);
269 kfree(rv->nodes);
270 kfree(rv);
271 }
272 }
273
dlm_recoverd(void * arg)274 static int dlm_recoverd(void *arg)
275 {
276 struct dlm_ls *ls;
277
278 ls = dlm_find_lockspace_local(arg);
279 if (!ls) {
280 log_print("dlm_recoverd: no lockspace %p", arg);
281 return -1;
282 }
283
284 down_write(&ls->ls_in_recovery);
285 set_bit(LSFL_RECOVER_LOCK, &ls->ls_flags);
286 wake_up(&ls->ls_recover_lock_wait);
287
288 while (1) {
289 /*
290 * We call kthread_should_stop() after set_current_state().
291 * This is because it works correctly if kthread_stop() is
292 * called just before set_current_state().
293 */
294 set_current_state(TASK_INTERRUPTIBLE);
295 if (kthread_should_stop()) {
296 set_current_state(TASK_RUNNING);
297 break;
298 }
299 if (!test_bit(LSFL_RECOVER_WORK, &ls->ls_flags) &&
300 !test_bit(LSFL_RECOVER_DOWN, &ls->ls_flags)) {
301 if (kthread_should_stop())
302 break;
303 schedule();
304 }
305 set_current_state(TASK_RUNNING);
306
307 if (test_and_clear_bit(LSFL_RECOVER_DOWN, &ls->ls_flags)) {
308 down_write(&ls->ls_in_recovery);
309 set_bit(LSFL_RECOVER_LOCK, &ls->ls_flags);
310 wake_up(&ls->ls_recover_lock_wait);
311 }
312
313 if (test_and_clear_bit(LSFL_RECOVER_WORK, &ls->ls_flags))
314 do_ls_recovery(ls);
315 }
316
317 if (test_bit(LSFL_RECOVER_LOCK, &ls->ls_flags))
318 up_write(&ls->ls_in_recovery);
319
320 dlm_put_lockspace(ls);
321 return 0;
322 }
323
dlm_recoverd_start(struct dlm_ls * ls)324 int dlm_recoverd_start(struct dlm_ls *ls)
325 {
326 struct task_struct *p;
327 int error = 0;
328
329 p = kthread_run(dlm_recoverd, ls, "dlm_recoverd");
330 if (IS_ERR(p))
331 error = PTR_ERR(p);
332 else
333 ls->ls_recoverd_task = p;
334 return error;
335 }
336
dlm_recoverd_stop(struct dlm_ls * ls)337 void dlm_recoverd_stop(struct dlm_ls *ls)
338 {
339 kthread_stop(ls->ls_recoverd_task);
340 }
341
dlm_recoverd_suspend(struct dlm_ls * ls)342 void dlm_recoverd_suspend(struct dlm_ls *ls)
343 {
344 wake_up(&ls->ls_wait_general);
345 mutex_lock(&ls->ls_recoverd_active);
346 }
347
dlm_recoverd_resume(struct dlm_ls * ls)348 void dlm_recoverd_resume(struct dlm_ls *ls)
349 {
350 mutex_unlock(&ls->ls_recoverd_active);
351 }
352
353