1 /****************************************************************************** 2 ******************************************************************************* 3 ** 4 ** Copyright (C) Sistina Software, Inc. 1997-2003 All rights reserved. 5 ** Copyright (C) 2004-2011 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"requestqueue.h" 23 #include "recoverd.h" 24 25 26 /* If the start for which we're re-enabling locking (seq) has been superseded 27 by a newer stop (ls_recover_seq), we need to leave locking disabled. 28 29 We suspend dlm_recv threads here to avoid the race where dlm_recv a) sees 30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 clear_bit(LSFL_RECOVER_LOCK, &ls->ls_flags); 45 error = 0; 46 } 47 spin_unlock(&ls->ls_recover_lock); 48 49 up_write(&ls->ls_recv_active); 50 return error; 51 } 52 53 static int ls_recover(struct dlm_ls *ls, struct dlm_recover *rv) 54 { 55 unsigned long start; 56 int error, neg = 0; 57 58 log_rinfo(ls, "dlm_recover %llu", (unsigned long long)rv->seq); 59 60 mutex_lock(&ls->ls_recoverd_active); 61 62 dlm_callback_suspend(ls); 63 64 dlm_clear_toss(ls); 65 66 /* 67 * This list of root rsb's will be the basis of most of the recovery 68 * routines. 69 */ 70 71 dlm_create_root_list(ls); 72 73 /* 74 * Add or remove nodes from the lockspace's ls_nodes list. 75 */ 76 77 error = dlm_recover_members(ls, rv, &neg); 78 if (error) { 79 log_rinfo(ls, "dlm_recover_members error %d", error); 80 goto fail; 81 } 82 83 dlm_recover_dir_nodeid(ls); 84 85 ls->ls_recover_dir_sent_res = 0; 86 ls->ls_recover_dir_sent_msg = 0; 87 ls->ls_recover_locks_in = 0; 88 89 dlm_set_recover_status(ls, DLM_RS_NODES); 90 91 error = dlm_recover_members_wait(ls); 92 if (error) { 93 log_rinfo(ls, "dlm_recover_members_wait error %d", error); 94 goto fail; 95 } 96 97 start = jiffies; 98 99 /* 100 * Rebuild our own share of the directory by collecting from all other 101 * nodes their master rsb names that hash to us. 102 */ 103 104 error = dlm_recover_directory(ls); 105 if (error) { 106 log_rinfo(ls, "dlm_recover_directory error %d", error); 107 goto fail; 108 } 109 110 dlm_set_recover_status(ls, DLM_RS_DIR); 111 112 error = dlm_recover_directory_wait(ls); 113 if (error) { 114 log_rinfo(ls, "dlm_recover_directory_wait error %d", error); 115 goto fail; 116 } 117 118 log_rinfo(ls, "dlm_recover_directory %u out %u messages", 119 ls->ls_recover_dir_sent_res, ls->ls_recover_dir_sent_msg); 120 121 /* 122 * We may have outstanding operations that are waiting for a reply from 123 * a failed node. Mark these to be resent after recovery. Unlock and 124 * cancel ops can just be completed. 125 */ 126 127 dlm_recover_waiters_pre(ls); 128 129 error = dlm_recovery_stopped(ls); 130 if (error) 131 goto fail; 132 133 if (neg || dlm_no_directory(ls)) { 134 /* 135 * Clear lkb's for departed nodes. 136 */ 137 138 dlm_recover_purge(ls); 139 140 /* 141 * Get new master nodeid's for rsb's that were mastered on 142 * departed nodes. 143 */ 144 145 error = dlm_recover_masters(ls); 146 if (error) { 147 log_rinfo(ls, "dlm_recover_masters error %d", error); 148 goto fail; 149 } 150 151 /* 152 * Send our locks on remastered rsb's to the new masters. 153 */ 154 155 error = dlm_recover_locks(ls); 156 if (error) { 157 log_rinfo(ls, "dlm_recover_locks error %d", error); 158 goto fail; 159 } 160 161 dlm_set_recover_status(ls, DLM_RS_LOCKS); 162 163 error = dlm_recover_locks_wait(ls); 164 if (error) { 165 log_rinfo(ls, "dlm_recover_locks_wait error %d", error); 166 goto fail; 167 } 168 169 log_rinfo(ls, "dlm_recover_locks %u in", 170 ls->ls_recover_locks_in); 171 172 /* 173 * Finalize state in master rsb's now that all locks can be 174 * checked. This includes conversion resolution and lvb 175 * settings. 176 */ 177 178 dlm_recover_rsbs(ls); 179 } else { 180 /* 181 * Other lockspace members may be going through the "neg" steps 182 * while also adding us to the lockspace, in which case they'll 183 * be doing the recover_locks (RS_LOCKS) barrier. 184 */ 185 dlm_set_recover_status(ls, DLM_RS_LOCKS); 186 187 error = dlm_recover_locks_wait(ls); 188 if (error) { 189 log_rinfo(ls, "dlm_recover_locks_wait error %d", error); 190 goto fail; 191 } 192 } 193 194 dlm_release_root_list(ls); 195 196 /* 197 * Purge directory-related requests that are saved in requestqueue. 198 * All dir requests from before recovery are invalid now due to the dir 199 * rebuild and will be resent by the requesting nodes. 200 */ 201 202 dlm_purge_requestqueue(ls); 203 204 dlm_set_recover_status(ls, DLM_RS_DONE); 205 206 error = dlm_recover_done_wait(ls); 207 if (error) { 208 log_rinfo(ls, "dlm_recover_done_wait error %d", error); 209 goto fail; 210 } 211 212 dlm_clear_members_gone(ls); 213 214 dlm_adjust_timeouts(ls); 215 216 dlm_callback_resume(ls); 217 218 error = enable_locking(ls, rv->seq); 219 if (error) { 220 log_rinfo(ls, "enable_locking error %d", error); 221 goto fail; 222 } 223 224 error = dlm_process_requestqueue(ls); 225 if (error) { 226 log_rinfo(ls, "dlm_process_requestqueue error %d", error); 227 goto fail; 228 } 229 230 error = dlm_recover_waiters_post(ls); 231 if (error) { 232 log_rinfo(ls, "dlm_recover_waiters_post error %d", error); 233 goto fail; 234 } 235 236 dlm_recover_grant(ls); 237 238 log_rinfo(ls, "dlm_recover %llu generation %u done: %u ms", 239 (unsigned long long)rv->seq, ls->ls_generation, 240 jiffies_to_msecs(jiffies - start)); 241 mutex_unlock(&ls->ls_recoverd_active); 242 243 dlm_lsop_recover_done(ls); 244 return 0; 245 246 fail: 247 dlm_release_root_list(ls); 248 log_rinfo(ls, "dlm_recover %llu error %d", 249 (unsigned long long)rv->seq, error); 250 mutex_unlock(&ls->ls_recoverd_active); 251 return error; 252 } 253 254 /* The dlm_ls_start() that created the rv we take here may already have been 255 stopped via dlm_ls_stop(); in that case we need to leave the RECOVERY_STOP 256 flag set. */ 257 258 static void do_ls_recovery(struct dlm_ls *ls) 259 { 260 struct dlm_recover *rv = NULL; 261 262 spin_lock(&ls->ls_recover_lock); 263 rv = ls->ls_recover_args; 264 ls->ls_recover_args = NULL; 265 if (rv && ls->ls_recover_seq == rv->seq) 266 clear_bit(LSFL_RECOVER_STOP, &ls->ls_flags); 267 spin_unlock(&ls->ls_recover_lock); 268 269 if (rv) { 270 ls_recover(ls, rv); 271 kfree(rv->nodes); 272 kfree(rv); 273 } 274 } 275 276 static int dlm_recoverd(void *arg) 277 { 278 struct dlm_ls *ls; 279 280 ls = dlm_find_lockspace_local(arg); 281 if (!ls) { 282 log_print("dlm_recoverd: no lockspace %p", arg); 283 return -1; 284 } 285 286 down_write(&ls->ls_in_recovery); 287 set_bit(LSFL_RECOVER_LOCK, &ls->ls_flags); 288 wake_up(&ls->ls_recover_lock_wait); 289 290 while (1) { 291 /* 292 * We call kthread_should_stop() after set_current_state(). 293 * This is because it works correctly if kthread_stop() is 294 * called just before set_current_state(). 295 */ 296 set_current_state(TASK_INTERRUPTIBLE); 297 if (kthread_should_stop()) { 298 set_current_state(TASK_RUNNING); 299 break; 300 } 301 if (!test_bit(LSFL_RECOVER_WORK, &ls->ls_flags) && 302 !test_bit(LSFL_RECOVER_DOWN, &ls->ls_flags)) { 303 if (kthread_should_stop()) 304 break; 305 schedule(); 306 } 307 set_current_state(TASK_RUNNING); 308 309 if (test_and_clear_bit(LSFL_RECOVER_DOWN, &ls->ls_flags)) { 310 down_write(&ls->ls_in_recovery); 311 set_bit(LSFL_RECOVER_LOCK, &ls->ls_flags); 312 wake_up(&ls->ls_recover_lock_wait); 313 } 314 315 if (test_and_clear_bit(LSFL_RECOVER_WORK, &ls->ls_flags)) 316 do_ls_recovery(ls); 317 } 318 319 if (test_bit(LSFL_RECOVER_LOCK, &ls->ls_flags)) 320 up_write(&ls->ls_in_recovery); 321 322 dlm_put_lockspace(ls); 323 return 0; 324 } 325 326 int dlm_recoverd_start(struct dlm_ls *ls) 327 { 328 struct task_struct *p; 329 int error = 0; 330 331 p = kthread_run(dlm_recoverd, ls, "dlm_recoverd"); 332 if (IS_ERR(p)) 333 error = PTR_ERR(p); 334 else 335 ls->ls_recoverd_task = p; 336 return error; 337 } 338 339 void dlm_recoverd_stop(struct dlm_ls *ls) 340 { 341 kthread_stop(ls->ls_recoverd_task); 342 } 343 344 void dlm_recoverd_suspend(struct dlm_ls *ls) 345 { 346 wake_up(&ls->ls_wait_general); 347 mutex_lock(&ls->ls_recoverd_active); 348 } 349 350 void dlm_recoverd_resume(struct dlm_ls *ls) 351 { 352 mutex_unlock(&ls->ls_recoverd_active); 353 } 354 355