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"requestqueue.h" 23 #include "recoverd.h" 24 25 26 /* If the start for which we're re-enabling locking (seq) has been superseded 27 by a newer stop (ls_recover_seq), we need to leave locking disabled. 28 29 We suspend dlm_recv threads here to avoid the race where dlm_recv a) sees 30 locking stopped and b) adds a message to the requestqueue, but dlm_recoverd 31 enables locking and clears the requestqueue between a and b. */ 32 33 static int enable_locking(struct dlm_ls *ls, uint64_t seq) 34 { 35 int error = -EINTR; 36 37 down_write(&ls->ls_recv_active); 38 39 spin_lock(&ls->ls_recover_lock); 40 if (ls->ls_recover_seq == seq) { 41 set_bit(LSFL_RUNNING, &ls->ls_flags); 42 /* unblocks processes waiting to enter the dlm */ 43 up_write(&ls->ls_in_recovery); 44 error = 0; 45 } 46 spin_unlock(&ls->ls_recover_lock); 47 48 up_write(&ls->ls_recv_active); 49 return error; 50 } 51 52 static int ls_recover(struct dlm_ls *ls, struct dlm_recover *rv) 53 { 54 unsigned long start; 55 int error, neg = 0; 56 57 log_debug(ls, "recover %llx", (unsigned long long)rv->seq); 58 59 mutex_lock(&ls->ls_recoverd_active); 60 61 /* 62 * Suspending and resuming dlm_astd ensures that no lkb's from this ls 63 * will be processed by dlm_astd during recovery. 64 */ 65 66 dlm_astd_suspend(); 67 dlm_astd_resume(); 68 69 /* 70 * Free non-master tossed rsb's. Master rsb's are kept on toss 71 * list and put on root list to be included in resdir recovery. 72 */ 73 74 dlm_clear_toss_list(ls); 75 76 /* 77 * This list of root rsb's will be the basis of most of the recovery 78 * routines. 79 */ 80 81 dlm_create_root_list(ls); 82 83 /* 84 * Add or remove nodes from the lockspace's ls_nodes list. 85 * Also waits for all nodes to complete dlm_recover_members. 86 */ 87 88 error = dlm_recover_members(ls, rv, &neg); 89 if (error) { 90 log_debug(ls, "recover_members failed %d", error); 91 goto fail; 92 } 93 start = jiffies; 94 95 /* 96 * Rebuild our own share of the directory by collecting from all other 97 * nodes their master rsb names that hash to us. 98 */ 99 100 error = dlm_recover_directory(ls); 101 if (error) { 102 log_debug(ls, "recover_directory failed %d", error); 103 goto fail; 104 } 105 106 /* 107 * Wait for all nodes to complete directory rebuild. 108 */ 109 110 error = dlm_recover_directory_wait(ls); 111 if (error) { 112 log_debug(ls, "recover_directory_wait failed %d", error); 113 goto fail; 114 } 115 116 /* 117 * We may have outstanding operations that are waiting for a reply from 118 * a failed node. Mark these to be resent after recovery. Unlock and 119 * cancel ops can just be completed. 120 */ 121 122 dlm_recover_waiters_pre(ls); 123 124 error = dlm_recovery_stopped(ls); 125 if (error) 126 goto fail; 127 128 if (neg || dlm_no_directory(ls)) { 129 /* 130 * Clear lkb's for departed nodes. 131 */ 132 133 dlm_purge_locks(ls); 134 135 /* 136 * Get new master nodeid's for rsb's that were mastered on 137 * departed nodes. 138 */ 139 140 error = dlm_recover_masters(ls); 141 if (error) { 142 log_debug(ls, "recover_masters failed %d", error); 143 goto fail; 144 } 145 146 /* 147 * Send our locks on remastered rsb's to the new masters. 148 */ 149 150 error = dlm_recover_locks(ls); 151 if (error) { 152 log_debug(ls, "recover_locks failed %d", error); 153 goto fail; 154 } 155 156 error = dlm_recover_locks_wait(ls); 157 if (error) { 158 log_debug(ls, "recover_locks_wait failed %d", error); 159 goto fail; 160 } 161 162 /* 163 * Finalize state in master rsb's now that all locks can be 164 * checked. This includes conversion resolution and lvb 165 * settings. 166 */ 167 168 dlm_recover_rsbs(ls); 169 } else { 170 /* 171 * Other lockspace members may be going through the "neg" steps 172 * while also adding us to the lockspace, in which case they'll 173 * be doing the recover_locks (RS_LOCKS) barrier. 174 */ 175 dlm_set_recover_status(ls, DLM_RS_LOCKS); 176 177 error = dlm_recover_locks_wait(ls); 178 if (error) { 179 log_debug(ls, "recover_locks_wait failed %d", error); 180 goto fail; 181 } 182 } 183 184 dlm_release_root_list(ls); 185 186 /* 187 * Purge directory-related requests that are saved in requestqueue. 188 * All dir requests from before recovery are invalid now due to the dir 189 * rebuild and will be resent by the requesting nodes. 190 */ 191 192 dlm_purge_requestqueue(ls); 193 194 dlm_set_recover_status(ls, DLM_RS_DONE); 195 error = dlm_recover_done_wait(ls); 196 if (error) { 197 log_debug(ls, "recover_done_wait failed %d", error); 198 goto fail; 199 } 200 201 dlm_clear_members_gone(ls); 202 203 dlm_adjust_timeouts(ls); 204 205 error = enable_locking(ls, rv->seq); 206 if (error) { 207 log_debug(ls, "enable_locking failed %d", error); 208 goto fail; 209 } 210 211 error = dlm_process_requestqueue(ls); 212 if (error) { 213 log_debug(ls, "process_requestqueue failed %d", error); 214 goto fail; 215 } 216 217 error = dlm_recover_waiters_post(ls); 218 if (error) { 219 log_debug(ls, "recover_waiters_post failed %d", error); 220 goto fail; 221 } 222 223 dlm_grant_after_purge(ls); 224 225 dlm_astd_wake(); 226 227 log_debug(ls, "recover %llx done: %u ms", 228 (unsigned long long)rv->seq, 229 jiffies_to_msecs(jiffies - start)); 230 mutex_unlock(&ls->ls_recoverd_active); 231 232 return 0; 233 234 fail: 235 dlm_release_root_list(ls); 236 log_debug(ls, "recover %llx error %d", 237 (unsigned long long)rv->seq, error); 238 mutex_unlock(&ls->ls_recoverd_active); 239 return error; 240 } 241 242 /* The dlm_ls_start() that created the rv we take here may already have been 243 stopped via dlm_ls_stop(); in that case we need to leave the RECOVERY_STOP 244 flag set. */ 245 246 static void do_ls_recovery(struct dlm_ls *ls) 247 { 248 struct dlm_recover *rv = NULL; 249 250 spin_lock(&ls->ls_recover_lock); 251 rv = ls->ls_recover_args; 252 ls->ls_recover_args = NULL; 253 if (rv && ls->ls_recover_seq == rv->seq) 254 clear_bit(LSFL_RECOVERY_STOP, &ls->ls_flags); 255 spin_unlock(&ls->ls_recover_lock); 256 257 if (rv) { 258 ls_recover(ls, rv); 259 kfree(rv->nodeids); 260 kfree(rv->new); 261 kfree(rv); 262 } 263 } 264 265 static int dlm_recoverd(void *arg) 266 { 267 struct dlm_ls *ls; 268 269 ls = dlm_find_lockspace_local(arg); 270 if (!ls) { 271 log_print("dlm_recoverd: no lockspace %p", arg); 272 return -1; 273 } 274 275 while (!kthread_should_stop()) { 276 set_current_state(TASK_INTERRUPTIBLE); 277 if (!test_bit(LSFL_WORK, &ls->ls_flags)) 278 schedule(); 279 set_current_state(TASK_RUNNING); 280 281 if (test_and_clear_bit(LSFL_WORK, &ls->ls_flags)) 282 do_ls_recovery(ls); 283 } 284 285 dlm_put_lockspace(ls); 286 return 0; 287 } 288 289 void dlm_recoverd_kick(struct dlm_ls *ls) 290 { 291 set_bit(LSFL_WORK, &ls->ls_flags); 292 wake_up_process(ls->ls_recoverd_task); 293 } 294 295 int dlm_recoverd_start(struct dlm_ls *ls) 296 { 297 struct task_struct *p; 298 int error = 0; 299 300 p = kthread_run(dlm_recoverd, ls, "dlm_recoverd"); 301 if (IS_ERR(p)) 302 error = PTR_ERR(p); 303 else 304 ls->ls_recoverd_task = p; 305 return error; 306 } 307 308 void dlm_recoverd_stop(struct dlm_ls *ls) 309 { 310 kthread_stop(ls->ls_recoverd_task); 311 } 312 313 void dlm_recoverd_suspend(struct dlm_ls *ls) 314 { 315 wake_up(&ls->ls_wait_general); 316 mutex_lock(&ls->ls_recoverd_active); 317 } 318 319 void dlm_recoverd_resume(struct dlm_ls *ls) 320 { 321 mutex_unlock(&ls->ls_recoverd_active); 322 } 323 324