fs/ocfs2/dlm/dlmrecovery.c

   1 /* -*- mode: c; c-basic-offset: 8; -*-
   2  * vim: noexpandtab sw=8 ts=8 sts=0:
   3  *
   4  * dlmrecovery.c
   5  *
   6  * recovery stuff
   7  *
   8  * Copyright (C) 2004 Oracle.  All rights reserved.
   9  *
  10  * This program is free software; you can redistribute it and/or
  11  * modify it under the terms of the GNU General Public
  12  * License as published by the Free Software Foundation; either
  13  * version 2 of the License, or (at your option) any later version.
  14  *
  15  * This program is distributed in the hope that it will be useful,
  16  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  17  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  18  * General Public License for more details.
  19  *
  20  * You should have received a copy of the GNU General Public
  21  * License along with this program; if not, write to the
  22  * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
  23  * Boston, MA 021110-1307, USA.
  24  *
  25  */
  26
  27
  28 #include <linux/module.h>
  29 #include <linux/fs.h>
  30 #include <linux/types.h>
  31 #include <linux/slab.h>
  32 #include <linux/highmem.h>
  33 #include <linux/init.h>
  34 #include <linux/sysctl.h>
  35 #include <linux/random.h>
  36 #include <linux/blkdev.h>
  37 #include <linux/socket.h>
  38 #include <linux/inet.h>
  39 #include <linux/timer.h>
  40 #include <linux/kthread.h>
  41 #include <linux/delay.h>
  42
  43
  44 #include "cluster/heartbeat.h"
  45 #include "cluster/nodemanager.h"
  46 #include "cluster/tcp.h"
  47
  48 #include "dlmapi.h"
  49 #include "dlmcommon.h"
  50 #include "dlmdomain.h"
  51
  52 #define MLOG_MASK_PREFIX (ML_DLM|ML_DLM_RECOVERY)
  53 #include "cluster/masklog.h"
  54
  55 static void dlm_do_local_recovery_cleanup(struct dlm_ctxt *dlm, u8 dead_node);
  56
  57 static int dlm_recovery_thread(void *data);
  58 static int dlm_do_recovery(struct dlm_ctxt *dlm);
  59
  60 static int dlm_pick_recovery_master(struct dlm_ctxt *dlm);
  61 static int dlm_remaster_locks(struct dlm_ctxt *dlm, u8 dead_node);
  62 static int dlm_init_recovery_area(struct dlm_ctxt *dlm, u8 dead_node);
  63 static int dlm_request_all_locks(struct dlm_ctxt *dlm,
  64                                  u8 request_from, u8 dead_node);
  65 static void dlm_destroy_recovery_area(struct dlm_ctxt *dlm, u8 dead_node);
  66
  67 static inline int dlm_num_locks_in_lockres(struct dlm_lock_resource *res);
  68 static void dlm_init_migratable_lockres(struct dlm_migratable_lockres *mres,
  69                                         const char *lockname, int namelen,
  70                                         int total_locks, u64 cookie,
  71                                         u8 flags, u8 master);
  72 static int dlm_send_mig_lockres_msg(struct dlm_ctxt *dlm,
  73                                     struct dlm_migratable_lockres *mres,
  74                                     u8 send_to,
  75                                     struct dlm_lock_resource *res,
  76                                     int total_locks);
  77 static int dlm_process_recovery_data(struct dlm_ctxt *dlm,
  78                                      struct dlm_lock_resource *res,
  79                                      struct dlm_migratable_lockres *mres);
  80 static int dlm_send_finalize_reco_message(struct dlm_ctxt *dlm);
  81 static int dlm_send_all_done_msg(struct dlm_ctxt *dlm,
  82                                  u8 dead_node, u8 send_to);
  83 static int dlm_send_begin_reco_message(struct dlm_ctxt *dlm, u8 dead_node);
  84 static void dlm_move_reco_locks_to_list(struct dlm_ctxt *dlm,
  85                                         struct list_head *list, u8 dead_node);
  86 static void dlm_finish_local_lockres_recovery(struct dlm_ctxt *dlm,
  87                                               u8 dead_node, u8 new_master);
  88 static void dlm_reco_ast(void *astdata);
  89 static void dlm_reco_bast(void *astdata, int blocked_type);
  90 static void dlm_reco_unlock_ast(void *astdata, enum dlm_status st);
  91 static void dlm_request_all_locks_worker(struct dlm_work_item *item,
  92                                          void *data);
  93 static void dlm_mig_lockres_worker(struct dlm_work_item *item, void *data);
  94 static int dlm_lockres_master_requery(struct dlm_ctxt *dlm,
  95                                       struct dlm_lock_resource *res,
  96                                       u8 *real_master);
  97
  98 static u64 dlm_get_next_mig_cookie(void);
  99
 100 static DEFINE_SPINLOCK(dlm_reco_state_lock);
 101 static DEFINE_SPINLOCK(dlm_mig_cookie_lock);
 102 static u64 dlm_mig_cookie = 1;
 103
 104 static u64 dlm_get_next_mig_cookie(void)
 105 {
 106         u64 c;
 107         spin_lock(&dlm_mig_cookie_lock);
 108         c = dlm_mig_cookie;
 109         if (dlm_mig_cookie == (~0ULL))
 110                 dlm_mig_cookie = 1;
 111         else
 112                 dlm_mig_cookie++;
 113         spin_unlock(&dlm_mig_cookie_lock);
 114         return c;
 115 }
 116
 117 static inline void dlm_set_reco_dead_node(struct dlm_ctxt *dlm,
 118                                           u8 dead_node)
 119 {
 120         assert_spin_locked(&dlm->spinlock);
 121         if (dlm->reco.dead_node != dead_node)
 122                 mlog(0, "%s: changing dead_node from %u to %u\n",
 123                      dlm->name, dlm->reco.dead_node, dead_node);
 124         dlm->reco.dead_node = dead_node;
 125 }
 126
 127 static inline void dlm_set_reco_master(struct dlm_ctxt *dlm,
 128                                        u8 master)
 129 {
 130         assert_spin_locked(&dlm->spinlock);
 131         mlog(0, "%s: changing new_master from %u to %u\n",
 132              dlm->name, dlm->reco.new_master, master);
 133         dlm->reco.new_master = master;
 134 }
 135
 136 static inline void __dlm_reset_recovery(struct dlm_ctxt *dlm)
 137 {
 138         assert_spin_locked(&dlm->spinlock);
 139         clear_bit(dlm->reco.dead_node, dlm->recovery_map);
 140         dlm_set_reco_dead_node(dlm, O2NM_INVALID_NODE_NUM);
 141         dlm_set_reco_master(dlm, O2NM_INVALID_NODE_NUM);
 142 }
 143
 144 static inline void dlm_reset_recovery(struct dlm_ctxt *dlm)
 145 {
 146         spin_lock(&dlm->spinlock);
 147         __dlm_reset_recovery(dlm);
 148         spin_unlock(&dlm->spinlock);
 149 }
 150
 151 /* Worker function used during recovery. */
 152 void dlm_dispatch_work(struct work_struct *work)
 153 {
 154         struct dlm_ctxt *dlm =
 155                 container_of(work, struct dlm_ctxt, dispatched_work);
 156         LIST_HEAD(tmp_list);
 157         struct dlm_work_item *item, *next;
 158         dlm_workfunc_t *workfunc;
 159         int tot=0;
 160
 161         spin_lock(&dlm->work_lock);
 162         list_splice_init(&dlm->work_list, &tmp_list);
 163         spin_unlock(&dlm->work_lock);
 164
 165         list_for_each_entry(item, &tmp_list, list) {
 166                 tot++;
 167         }
 168         mlog(0, "%s: work thread has %d work items\n", dlm->name, tot);
 169
 170         list_for_each_entry_safe(item, next, &tmp_list, list) {
 171                 workfunc = item->func;
 172                 list_del_init(&item->list);
 173
 174                 /* already have ref on dlm to avoid having
 175                  * it disappear.  just double-check. */
 176                 BUG_ON(item->dlm != dlm);
 177
 178                 /* this is allowed to sleep and
 179                  * call network stuff */
 180                 workfunc(item, item->data);
 181
 182                 dlm_put(dlm);
 183                 kfree(item);
 184         }
 185 }
 186
 187 /*
 188  * RECOVERY THREAD
 189  */
 190
 191 void dlm_kick_recovery_thread(struct dlm_ctxt *dlm)
 192 {
 193         /* wake the recovery thread
 194          * this will wake the reco thread in one of three places
 195          * 1) sleeping with no recovery happening
 196          * 2) sleeping with recovery mastered elsewhere
 197          * 3) recovery mastered here, waiting on reco data */
 198
 199         wake_up(&dlm->dlm_reco_thread_wq);
 200 }
 201
 202 /* Launch the recovery thread */
 203 int dlm_launch_recovery_thread(struct dlm_ctxt *dlm)
 204 {
 205         mlog(0, "starting dlm recovery thread...\n");
 206
 207         dlm->dlm_reco_thread_task = kthread_run(dlm_recovery_thread, dlm,
 208                                                 "dlm_reco_thread");
 209         if (IS_ERR(dlm->dlm_reco_thread_task)) {
 210                 mlog_errno(PTR_ERR(dlm->dlm_reco_thread_task));
 211                 dlm->dlm_reco_thread_task = NULL;
 212                 return -EINVAL;
 213         }
 214
 215         return 0;
 216 }
 217
 218 void dlm_complete_recovery_thread(struct dlm_ctxt *dlm)
 219 {
 220         if (dlm->dlm_reco_thread_task) {
 221                 mlog(0, "waiting for dlm recovery thread to exit\n");
 222                 kthread_stop(dlm->dlm_reco_thread_task);
 223                 dlm->dlm_reco_thread_task = NULL;
 224         }
 225 }
 226
 227
 228
 229 /*
 230  * this is lame, but here's how recovery works...
 231  * 1) all recovery threads cluster wide will work on recovering
 232  *    ONE node at a time
 233  * 2) negotiate who will take over all the locks for the dead node.
 234  *    thats right... ALL the locks.
 235  * 3) once a new master is chosen, everyone scans all locks
 236  *    and moves aside those mastered by the dead guy
 237  * 4) each of these locks should be locked until recovery is done
 238  * 5) the new master collects up all of secondary lock queue info
 239  *    one lock at a time, forcing each node to communicate back
 240  *    before continuing
 241  * 6) each secondary lock queue responds with the full known lock info
 242  * 7) once the new master has run all its locks, it sends a ALLDONE!
 243  *    message to everyone
 244  * 8) upon receiving this message, the secondary queue node unlocks
 245  *    and responds to the ALLDONE
 246  * 9) once the new master gets responses from everyone, he unlocks
 247  *    everything and recovery for this dead node is done
 248  *10) go back to 2) while there are still dead nodes
 249  *
 250  */
 251
 252 static void dlm_print_reco_node_status(struct dlm_ctxt *dlm)
 253 {
 254         struct dlm_reco_node_data *ndata;
 255         struct dlm_lock_resource *res;
 256
 257         mlog(ML_NOTICE, "%s(%d): recovery info, state=%s, dead=%u, master=%u\n",
 258              dlm->name, task_pid_nr(dlm->dlm_reco_thread_task),
 259              dlm->reco.state & DLM_RECO_STATE_ACTIVE ? "ACTIVE" : "inactive",
 260              dlm->reco.dead_node, dlm->reco.new_master);
 261
 262         list_for_each_entry(ndata, &dlm->reco.node_data, list) {
 263                 char *st = "unknown";
 264                 switch (ndata->state) {
 265                         case DLM_RECO_NODE_DATA_INIT:
 266                                 st = "init";
 267                                 break;
 268                         case DLM_RECO_NODE_DATA_REQUESTING:
 269                                 st = "requesting";
 270                                 break;
 271                         case DLM_RECO_NODE_DATA_DEAD:
 272                                 st = "dead";
 273                                 break;
 274                         case DLM_RECO_NODE_DATA_RECEIVING:
 275                                 st = "receiving";
 276                                 break;
 277                         case DLM_RECO_NODE_DATA_REQUESTED:
 278                                 st = "requested";
 279                                 break;
 280                         case DLM_RECO_NODE_DATA_DONE:
 281                                 st = "done";
 282                                 break;
 283                         case DLM_RECO_NODE_DATA_FINALIZE_SENT:
 284                                 st = "finalize-sent";
 285                                 break;
 286                         default:
 287                                 st = "bad";
 288                                 break;
 289                 }
 290                 mlog(ML_NOTICE, "%s: reco state, node %u, state=%s\n",
 291                      dlm->name, ndata->node_num, st);
 292         }
 293         list_for_each_entry(res, &dlm->reco.resources, recovering) {
 294                 mlog(ML_NOTICE, "%s: lockres %.*s on recovering list\n",
 295                      dlm->name, res->lockname.len, res->lockname.name);
 296         }
 297 }
 298
 299 #define DLM_RECO_THREAD_TIMEOUT_MS (5 * 1000)
 300
 301 static int dlm_recovery_thread(void *data)
 302 {
 303         int status;
 304         struct dlm_ctxt *dlm = data;
 305         unsigned long timeout = msecs_to_jiffies(DLM_RECO_THREAD_TIMEOUT_MS);
 306
 307         mlog(0, "dlm thread running for %s...\n", dlm->name);
 308
 309         while (!kthread_should_stop()) {
 310                 if (dlm_domain_fully_joined(dlm)) {
 311                         status = dlm_do_recovery(dlm);
 312                         if (status == -EAGAIN) {
 313                                 /* do not sleep, recheck immediately. */
 314                                 continue;
 315                         }
 316                         if (status < 0)
 317                                 mlog_errno(status);
 318                 }
 319
 320                 wait_event_interruptible_timeout(dlm->dlm_reco_thread_wq,
 321                                                  kthread_should_stop(),
 322                                                  timeout);
 323         }
 324
 325         mlog(0, "quitting DLM recovery thread\n");
 326         return 0;
 327 }
 328
 329 /* returns true when the recovery master has contacted us */
 330 static int dlm_reco_master_ready(struct dlm_ctxt *dlm)
 331 {
 332         int ready;
 333         spin_lock(&dlm->spinlock);
 334         ready = (dlm->reco.new_master != O2NM_INVALID_NODE_NUM);
 335         spin_unlock(&dlm->spinlock);
 336         return ready;
 337 }
 338
 339 /* returns true if node is no longer in the domain
 340  * could be dead or just not joined */
 341 int dlm_is_node_dead(struct dlm_ctxt *dlm, u8 node)
 342 {
 343         int dead;
 344         spin_lock(&dlm->spinlock);
 345         dead = !test_bit(node, dlm->domain_map);
 346         spin_unlock(&dlm->spinlock);
 347         return dead;
 348 }
 349
 350 /* returns true if node is no longer in the domain
 351  * could be dead or just not joined */
 352 static int dlm_is_node_recovered(struct dlm_ctxt *dlm, u8 node)
 353 {
 354         int recovered;
 355         spin_lock(&dlm->spinlock);
 356         recovered = !test_bit(node, dlm->recovery_map);
 357         spin_unlock(&dlm->spinlock);
 358         return recovered;
 359 }
 360
 361
 362 void dlm_wait_for_node_death(struct dlm_ctxt *dlm, u8 node, int timeout)
 363 {
 364         if (dlm_is_node_dead(dlm, node))
 365                 return;
 366
 367         printk(KERN_NOTICE "o2dlm: Waiting on the death of node %u in "
 368                "domain %s\n", node, dlm->name);
 369
 370         if (timeout)
 371                 wait_event_timeout(dlm->dlm_reco_thread_wq,
 372                                    dlm_is_node_dead(dlm, node),
 373                                    msecs_to_jiffies(timeout));
 374         else
 375                 wait_event(dlm->dlm_reco_thread_wq,
 376                            dlm_is_node_dead(dlm, node));
 377 }
 378
 379 void dlm_wait_for_node_recovery(struct dlm_ctxt *dlm, u8 node, int timeout)
 380 {
 381         if (dlm_is_node_recovered(dlm, node))
 382                 return;
 383
 384         printk(KERN_NOTICE "o2dlm: Waiting on the recovery of node %u in "
 385                "domain %s\n", node, dlm->name);
 386
 387         if (timeout)
 388                 wait_event_timeout(dlm->dlm_reco_thread_wq,
 389                                    dlm_is_node_recovered(dlm, node),
 390                                    msecs_to_jiffies(timeout));
 391         else
 392                 wait_event(dlm->dlm_reco_thread_wq,
 393                            dlm_is_node_recovered(dlm, node));
 394 }
 395
 396 /* callers of the top-level api calls (dlmlock/dlmunlock) should
 397  * block on the dlm->reco.event when recovery is in progress.
 398  * the dlm recovery thread will set this state when it begins
 399  * recovering a dead node (as the new master or not) and clear
 400  * the state and wake as soon as all affected lock resources have
 401  * been marked with the RECOVERY flag */
 402 static int dlm_in_recovery(struct dlm_ctxt *dlm)
 403 {
 404         int in_recovery;
 405         spin_lock(&dlm->spinlock);
 406         in_recovery = !!(dlm->reco.state & DLM_RECO_STATE_ACTIVE);
 407         spin_unlock(&dlm->spinlock);
 408         return in_recovery;
 409 }
 410
 411
 412 void dlm_wait_for_recovery(struct dlm_ctxt *dlm)
 413 {
 414         if (dlm_in_recovery(dlm)) {
 415                 mlog(0, "%s: reco thread %d in recovery: "
 416                      "state=%d, master=%u, dead=%u\n",
 417                      dlm->name, task_pid_nr(dlm->dlm_reco_thread_task),
 418                      dlm->reco.state, dlm->reco.new_master,
 419                      dlm->reco.dead_node);
 420         }
 421         wait_event(dlm->reco.event, !dlm_in_recovery(dlm));
 422 }
 423
 424 static void dlm_begin_recovery(struct dlm_ctxt *dlm)
 425 {
 426         spin_lock(&dlm->spinlock);
 427         BUG_ON(dlm->reco.state & DLM_RECO_STATE_ACTIVE);
 428         printk(KERN_NOTICE "o2dlm: Begin recovery on domain %s for node %u\n",
 429                dlm->name, dlm->reco.dead_node);
 430         dlm->reco.state |= DLM_RECO_STATE_ACTIVE;
 431         spin_unlock(&dlm->spinlock);
 432 }
 433
 434 static void dlm_end_recovery(struct dlm_ctxt *dlm)
 435 {
 436         spin_lock(&dlm->spinlock);
 437         BUG_ON(!(dlm->reco.state & DLM_RECO_STATE_ACTIVE));
 438         dlm->reco.state &= ~DLM_RECO_STATE_ACTIVE;
 439         spin_unlock(&dlm->spinlock);
 440         printk(KERN_NOTICE "o2dlm: End recovery on domain %s\n", dlm->name);
 441         wake_up(&dlm->reco.event);
 442 }
 443
 444 static void dlm_print_recovery_master(struct dlm_ctxt *dlm)
 445 {
 446         printk(KERN_NOTICE "o2dlm: Node %u (%s) is the Recovery Master for the "
 447                "dead node %u in domain %s\n", dlm->reco.new_master,
 448                (dlm->node_num == dlm->reco.new_master ? "me" : "he"),
 449                dlm->reco.dead_node, dlm->name);
 450 }
 451
 452 static int dlm_do_recovery(struct dlm_ctxt *dlm)
 453 {
 454         int status = 0;
 455         int ret;
 456
 457         spin_lock(&dlm->spinlock);
 458
 459         /* check to see if the new master has died */
 460         if (dlm->reco.new_master != O2NM_INVALID_NODE_NUM &&
 461             test_bit(dlm->reco.new_master, dlm->recovery_map)) {
 462                 mlog(0, "new master %u died while recovering %u!\n",
 463                      dlm->reco.new_master, dlm->reco.dead_node);
 464                 /* unset the new_master, leave dead_node */
 465                 dlm_set_reco_master(dlm, O2NM_INVALID_NODE_NUM);
 466         }
 467
 468         /* select a target to recover */
 469         if (dlm->reco.dead_node == O2NM_INVALID_NODE_NUM) {
 470                 int bit;
 471
 472                 bit = find_next_bit (dlm->recovery_map, O2NM_MAX_NODES, 0);
 473                 if (bit >= O2NM_MAX_NODES || bit < 0)
 474                         dlm_set_reco_dead_node(dlm, O2NM_INVALID_NODE_NUM);
 475                 else
 476                         dlm_set_reco_dead_node(dlm, bit);
 477         } else if (!test_bit(dlm->reco.dead_node, dlm->recovery_map)) {
 478                 /* BUG? */
 479                 mlog(ML_ERROR, "dead_node %u no longer in recovery map!\n",
 480                      dlm->reco.dead_node);
 481                 dlm_set_reco_dead_node(dlm, O2NM_INVALID_NODE_NUM);
 482         }
 483
 484         if (dlm->reco.dead_node == O2NM_INVALID_NODE_NUM) {
 485                 // mlog(0, "nothing to recover!  sleeping now!\n");
 486                 spin_unlock(&dlm->spinlock);
 487                 /* return to main thread loop and sleep. */
 488                 return 0;
 489         }
 490         mlog(0, "%s(%d):recovery thread found node %u in the recovery map!\n",
 491              dlm->name, task_pid_nr(dlm->dlm_reco_thread_task),
 492              dlm->reco.dead_node);
 493         spin_unlock(&dlm->spinlock);
 494
 495         /* take write barrier */
 496         /* (stops the list reshuffling thread, proxy ast handling) */
 497         dlm_begin_recovery(dlm);
 498
 499         if (dlm->reco.new_master == dlm->node_num)
 500                 goto master_here;
 501
 502         if (dlm->reco.new_master == O2NM_INVALID_NODE_NUM) {
 503                 /* choose a new master, returns 0 if this node
 504                  * is the master, -EEXIST if it's another node.
 505                  * this does not return until a new master is chosen
 506                  * or recovery completes entirely. */
 507                 ret = dlm_pick_recovery_master(dlm);
 508                 if (!ret) {
 509                         /* already notified everyone.  go. */
 510                         goto master_here;
 511                 }
 512                 mlog(0, "another node will master this recovery session.\n");
 513         }
 514
 515         dlm_print_recovery_master(dlm);
 516
 517         /* it is safe to start everything back up here
 518          * because all of the dead node's lock resources
 519          * have been marked as in-recovery */
 520         dlm_end_recovery(dlm);
 521
 522         /* sleep out in main dlm_recovery_thread loop. */
 523         return 0;
 524
 525 master_here:
 526         dlm_print_recovery_master(dlm);
 527
 528         status = dlm_remaster_locks(dlm, dlm->reco.dead_node);
 529         if (status < 0) {
 530                 /* we should never hit this anymore */
 531                 mlog(ML_ERROR, "%s: Error %d remastering locks for node %u, "
 532                      "retrying.\n", dlm->name, status, dlm->reco.dead_node);
 533                 /* yield a bit to allow any final network messages
 534                  * to get handled on remaining nodes */
 535                 msleep(100);
 536         } else {
 537                 /* success!  see if any other nodes need recovery */
 538                 mlog(0, "DONE mastering recovery of %s:%u here(this=%u)!\n",
 539                      dlm->name, dlm->reco.dead_node, dlm->node_num);
 540                 dlm_reset_recovery(dlm);
 541         }
 542         dlm_end_recovery(dlm);
 543
 544         /* continue and look for another dead node */
 545         return -EAGAIN;
 546 }
 547
 548 static int dlm_remaster_locks(struct dlm_ctxt *dlm, u8 dead_node)
 549 {
 550         int status = 0;
 551         struct dlm_reco_node_data *ndata;
 552         int all_nodes_done;
 553         int destroy = 0;
 554         int pass = 0;
 555
 556         do {
 557                 /* we have become recovery master.  there is no escaping
 558                  * this, so just keep trying until we get it. */
 559                 status = dlm_init_recovery_area(dlm, dead_node);
 560                 if (status < 0) {
 561                         mlog(ML_ERROR, "%s: failed to alloc recovery area, "
 562                              "retrying\n", dlm->name);
 563                         msleep(1000);
 564                 }
 565         } while (status != 0);
 566
 567         /* safe to access the node data list without a lock, since this
 568          * process is the only one to change the list */
 569         list_for_each_entry(ndata, &dlm->reco.node_data, list) {
 570                 BUG_ON(ndata->state != DLM_RECO_NODE_DATA_INIT);
 571                 ndata->state = DLM_RECO_NODE_DATA_REQUESTING;
 572
 573                 mlog(0, "%s: Requesting lock info from node %u\n", dlm->name,
 574                      ndata->node_num);
 575
 576                 if (ndata->node_num == dlm->node_num) {
 577                         ndata->state = DLM_RECO_NODE_DATA_DONE;
 578                         continue;
 579                 }
 580
 581                 do {
 582                         status = dlm_request_all_locks(dlm, ndata->node_num,
 583                                                        dead_node);
 584                         if (status < 0) {
 585                                 mlog_errno(status);
 586                                 if (dlm_is_host_down(status)) {
 587                                         /* node died, ignore it for recovery */
 588                                         status = 0;
 589                                         ndata->state = DLM_RECO_NODE_DATA_DEAD;
 590                                         /* wait for the domain map to catch up
 591                                          * with the network state. */
 592                                         wait_event_timeout(dlm->dlm_reco_thread_wq,
 593                                                            dlm_is_node_dead(dlm,
 594                                                                 ndata->node_num),
 595                                                            msecs_to_jiffies(1000));
 596                                         mlog(0, "waited 1 sec for %u, "
 597                                              "dead? %s\n", ndata->node_num,
 598                                              dlm_is_node_dead(dlm, ndata->node_num) ?
 599                                              "yes" : "no");
 600                                 } else {
 601                                         /* -ENOMEM on the other node */
 602                                         mlog(0, "%s: node %u returned "
 603                                              "%d during recovery, retrying "
 604                                              "after a short wait\n",
 605                                              dlm->name, ndata->node_num,
 606                                              status);
 607                                         msleep(100);
 608                                 }
 609                         }
 610                 } while (status != 0);
 611
 612                 spin_lock(&dlm_reco_state_lock);
 613                 switch (ndata->state) {
 614                         case DLM_RECO_NODE_DATA_INIT:
 615                         case DLM_RECO_NODE_DATA_FINALIZE_SENT:
 616                         case DLM_RECO_NODE_DATA_REQUESTED:
 617                                 BUG();
 618                                 break;
 619                         case DLM_RECO_NODE_DATA_DEAD:
 620                                 mlog(0, "node %u died after requesting "
 621                                      "recovery info for node %u\n",
 622                                      ndata->node_num, dead_node);
 623                                 /* fine.  don't need this node's info.
 624                                  * continue without it. */
 625                                 break;
 626                         case DLM_RECO_NODE_DATA_REQUESTING:
 627                                 ndata->state = DLM_RECO_NODE_DATA_REQUESTED;
 628                                 mlog(0, "now receiving recovery data from "
 629                                      "node %u for dead node %u\n",
 630                                      ndata->node_num, dead_node);
 631                                 break;
 632                         case DLM_RECO_NODE_DATA_RECEIVING:
 633                                 mlog(0, "already receiving recovery data from "
 634                                      "node %u for dead node %u\n",
 635                                      ndata->node_num, dead_node);
 636                                 break;
 637                         case DLM_RECO_NODE_DATA_DONE:
 638                                 mlog(0, "already DONE receiving recovery data "
 639                                      "from node %u for dead node %u\n",
 640                                      ndata->node_num, dead_node);
 641                                 break;
 642                 }
 643                 spin_unlock(&dlm_reco_state_lock);
 644         }
 645
 646         mlog(0, "%s: Done requesting all lock info\n", dlm->name);
 647
 648         /* nodes should be sending reco data now
 649          * just need to wait */
 650
 651         while (1) {
 652                 /* check all the nodes now to see if we are
 653                  * done, or if anyone died */
 654                 all_nodes_done = 1;
 655                 spin_lock(&dlm_reco_state_lock);
 656                 list_for_each_entry(ndata, &dlm->reco.node_data, list) {
 657                         mlog(0, "checking recovery state of node %u\n",
 658                              ndata->node_num);
 659                         switch (ndata->state) {
 660                                 case DLM_RECO_NODE_DATA_INIT:
 661                                 case DLM_RECO_NODE_DATA_REQUESTING:
 662                                         mlog(ML_ERROR, "bad ndata state for "
 663                                              "node %u: state=%d\n",
 664                                              ndata->node_num, ndata->state);
 665                                         BUG();
 666                                         break;
 667                                 case DLM_RECO_NODE_DATA_DEAD:
 668                                         mlog(0, "node %u died after "
 669                                              "requesting recovery info for "
 670                                              "node %u\n", ndata->node_num,
 671                                              dead_node);
 672                                         break;
 673                                 case DLM_RECO_NODE_DATA_RECEIVING:
 674                                 case DLM_RECO_NODE_DATA_REQUESTED:
 675                                         mlog(0, "%s: node %u still in state %s\n",
 676                                              dlm->name, ndata->node_num,
 677                                              ndata->state==DLM_RECO_NODE_DATA_RECEIVING ?
 678                                              "receiving" : "requested");
 679                                         all_nodes_done = 0;
 680                                         break;
 681                                 case DLM_RECO_NODE_DATA_DONE:
 682                                         mlog(0, "%s: node %u state is done\n",
 683                                              dlm->name, ndata->node_num);
 684                                         break;
 685                                 case DLM_RECO_NODE_DATA_FINALIZE_SENT:
 686                                         mlog(0, "%s: node %u state is finalize\n",
 687                                              dlm->name, ndata->node_num);
 688                                         break;
 689                         }
 690                 }
 691                 spin_unlock(&dlm_reco_state_lock);
 692
 693                 mlog(0, "pass #%d, all_nodes_done?: %s\n", ++pass,
 694                      all_nodes_done?"yes":"no");
 695                 if (all_nodes_done) {
 696                         int ret;
 697
 698                         /* all nodes are now in DLM_RECO_NODE_DATA_DONE state
 699                          * just send a finalize message to everyone and
 700                          * clean up */
 701                         mlog(0, "all nodes are done! send finalize\n");
 702                         ret = dlm_send_finalize_reco_message(dlm);
 703                         if (ret < 0)
 704                                 mlog_errno(ret);
 705
 706                         spin_lock(&dlm->spinlock);
 707                         dlm_finish_local_lockres_recovery(dlm, dead_node,
 708                                                           dlm->node_num);
 709                         spin_unlock(&dlm->spinlock);
 710                         mlog(0, "should be done with recovery!\n");
 711
 712                         mlog(0, "finishing recovery of %s at %lu, "
 713                              "dead=%u, this=%u, new=%u\n", dlm->name,
 714                              jiffies, dlm->reco.dead_node,
 715                              dlm->node_num, dlm->reco.new_master);
 716                         destroy = 1;
 717                         status = 0;
 718                         /* rescan everything marked dirty along the way */
 719                         dlm_kick_thread(dlm, NULL);
 720                         break;
 721                 }
 722                 /* wait to be signalled, with periodic timeout
 723                  * to check for node death */
 724                 wait_event_interruptible_timeout(dlm->dlm_reco_thread_wq,
 725                                          kthread_should_stop(),
 726                                          msecs_to_jiffies(DLM_RECO_THREAD_TIMEOUT_MS));
 727
 728         }
 729
 730         if (destroy)
 731                 dlm_destroy_recovery_area(dlm, dead_node);
 732
 733         return status;
 734 }
 735
 736 static int dlm_init_recovery_area(struct dlm_ctxt *dlm, u8 dead_node)
 737 {
 738         int num=0;
 739         struct dlm_reco_node_data *ndata;
 740
 741         spin_lock(&dlm->spinlock);
 742         memcpy(dlm->reco.node_map, dlm->domain_map, sizeof(dlm->domain_map));
 743         /* nodes can only be removed (by dying) after dropping
 744          * this lock, and death will be trapped later, so this should do */
 745         spin_unlock(&dlm->spinlock);
 746
 747         while (1) {
 748                 num = find_next_bit (dlm->reco.node_map, O2NM_MAX_NODES, num);
 749                 if (num >= O2NM_MAX_NODES) {
 750                         break;
 751                 }
 752                 BUG_ON(num == dead_node);
 753
 754                 ndata = kzalloc(sizeof(*ndata), GFP_NOFS);
 755                 if (!ndata) {
 756                         dlm_destroy_recovery_area(dlm, dead_node);
 757                         return -ENOMEM;
 758                 }
 759                 ndata->node_num = num;
 760                 ndata->state = DLM_RECO_NODE_DATA_INIT;
 761                 spin_lock(&dlm_reco_state_lock);
 762                 list_add_tail(&ndata->list, &dlm->reco.node_data);
 763                 spin_unlock(&dlm_reco_state_lock);
 764                 num++;
 765         }
 766
 767         return 0;
 768 }
 769
 770 static void dlm_destroy_recovery_area(struct dlm_ctxt *dlm, u8 dead_node)
 771 {
 772         struct dlm_reco_node_data *ndata, *next;
 773         LIST_HEAD(tmplist);
 774
 775         spin_lock(&dlm_reco_state_lock);
 776         list_splice_init(&dlm->reco.node_data, &tmplist);
 777         spin_unlock(&dlm_reco_state_lock);
 778
 779         list_for_each_entry_safe(ndata, next, &tmplist, list) {
 780                 list_del_init(&ndata->list);
 781                 kfree(ndata);
 782         }
 783 }
 784
 785 static int dlm_request_all_locks(struct dlm_ctxt *dlm, u8 request_from,
 786                                  u8 dead_node)
 787 {
 788         struct dlm_lock_request lr;
 789         int ret;
 790         int status;
 791
 792         mlog(0, "\n");
 793
 794
 795         mlog(0, "dlm_request_all_locks: dead node is %u, sending request "
 796                   "to %u\n", dead_node, request_from);
 797
 798         memset(&lr, 0, sizeof(lr));
 799         lr.node_idx = dlm->node_num;
 800         lr.dead_node = dead_node;
 801
 802         // send message
 803         ret = o2net_send_message(DLM_LOCK_REQUEST_MSG, dlm->key,
 804                                  &lr, sizeof(lr), request_from, &status);
 805
 806         /* negative status is handled by caller */
 807         if (ret < 0)
 808                 mlog(ML_ERROR, "%s: Error %d send LOCK_REQUEST to node %u "
 809                      "to recover dead node %u\n", dlm->name, ret,
 810                      request_from, dead_node);
 811         else
 812                 ret = status;
 813         // return from here, then
 814         // sleep until all received or error
 815         return ret;
 816
 817 }
 818
 819 int dlm_request_all_locks_handler(struct o2net_msg *msg, u32 len, void *data,
 820                                   void **ret_data)
 821 {
 822         struct dlm_ctxt *dlm = data;
 823         struct dlm_lock_request *lr = (struct dlm_lock_request *)msg->buf;
 824         char *buf = NULL;
 825         struct dlm_work_item *item = NULL;
 826
 827         if (!dlm_grab(dlm))
 828                 return -EINVAL;
 829
 830         if (lr->dead_node != dlm->reco.dead_node) {
 831                 mlog(ML_ERROR, "%s: node %u sent dead_node=%u, but local "
 832                      "dead_node is %u\n", dlm->name, lr->node_idx,
 833                      lr->dead_node, dlm->reco.dead_node);
 834                 dlm_print_reco_node_status(dlm);
 835                 /* this is a hack */
 836                 dlm_put(dlm);
 837                 return -ENOMEM;
 838         }
 839         BUG_ON(lr->dead_node != dlm->reco.dead_node);
 840
 841         item = kzalloc(sizeof(*item), GFP_NOFS);
 842         if (!item) {
 843                 dlm_put(dlm);
 844                 return -ENOMEM;
 845         }
 846
 847         /* this will get freed by dlm_request_all_locks_worker */
 848         buf = (char *) __get_free_page(GFP_NOFS);
 849         if (!buf) {
 850                 kfree(item);
 851                 dlm_put(dlm);
 852                 return -ENOMEM;
 853         }
 854
 855         /* queue up work for dlm_request_all_locks_worker */
 856         dlm_grab(dlm);  /* get an extra ref for the work item */
 857         dlm_init_work_item(dlm, item, dlm_request_all_locks_worker, buf);
 858         item->u.ral.reco_master = lr->node_idx;
 859         item->u.ral.dead_node = lr->dead_node;
 860         spin_lock(&dlm->work_lock);
 861         list_add_tail(&item->list, &dlm->work_list);
 862         spin_unlock(&dlm->work_lock);
 863         queue_work(dlm->dlm_worker, &dlm->dispatched_work);
 864
 865         dlm_put(dlm);
 866         return 0;
 867 }
 868
 869 static void dlm_request_all_locks_worker(struct dlm_work_item *item, void *data)
 870 {
 871         struct dlm_migratable_lockres *mres;
 872         struct dlm_lock_resource *res;
 873         struct dlm_ctxt *dlm;
 874         LIST_HEAD(resources);
 875         int ret;
 876         u8 dead_node, reco_master;
 877         int skip_all_done = 0;
 878
 879         dlm = item->dlm;
 880         dead_node = item->u.ral.dead_node;
 881         reco_master = item->u.ral.reco_master;
 882         mres = (struct dlm_migratable_lockres *)data;
 883
 884         mlog(0, "%s: recovery worker started, dead=%u, master=%u\n",
 885              dlm->name, dead_node, reco_master);
 886
 887         if (dead_node != dlm->reco.dead_node ||
 888             reco_master != dlm->reco.new_master) {
 889                 /* worker could have been created before the recovery master
 890                  * died.  if so, do not continue, but do not error. */
 891                 if (dlm->reco.new_master == O2NM_INVALID_NODE_NUM) {
 892                         mlog(ML_NOTICE, "%s: will not send recovery state, "
 893                              "recovery master %u died, thread=(dead=%u,mas=%u)"
 894                              " current=(dead=%u,mas=%u)\n", dlm->name,
 895                              reco_master, dead_node, reco_master,
 896                              dlm->reco.dead_node, dlm->reco.new_master);
 897                 } else {
 898                         mlog(ML_NOTICE, "%s: reco state invalid: reco(dead=%u, "
 899                              "master=%u), request(dead=%u, master=%u)\n",
 900                              dlm->name, dlm->reco.dead_node,
 901                              dlm->reco.new_master, dead_node, reco_master);
 902                 }
 903                 goto leave;
 904         }
 905
 906         /* lock resources should have already been moved to the
 907          * dlm->reco.resources list.  now move items from that list
 908          * to a temp list if the dead owner matches.  note that the
 909          * whole cluster recovers only one node at a time, so we
 910          * can safely move UNKNOWN lock resources for each recovery
 911          * session. */
 912         dlm_move_reco_locks_to_list(dlm, &resources, dead_node);
 913
 914         /* now we can begin blasting lockreses without the dlm lock */
 915
 916         /* any errors returned will be due to the new_master dying,
 917          * the dlm_reco_thread should detect this */
 918         list_for_each_entry(res, &resources, recovering) {
 919                 ret = dlm_send_one_lockres(dlm, res, mres, reco_master,
 920                                         DLM_MRES_RECOVERY);
 921                 if (ret < 0) {
 922                         mlog(ML_ERROR, "%s: node %u went down while sending "
 923                              "recovery state for dead node %u, ret=%d\n", dlm->name,
 924                              reco_master, dead_node, ret);
 925                         skip_all_done = 1;
 926                         break;
 927                 }
 928         }
 929
 930         /* move the resources back to the list */
 931         spin_lock(&dlm->spinlock);
 932         list_splice_init(&resources, &dlm->reco.resources);
 933         spin_unlock(&dlm->spinlock);
 934
 935         if (!skip_all_done) {
 936                 ret = dlm_send_all_done_msg(dlm, dead_node, reco_master);
 937                 if (ret < 0) {
 938                         mlog(ML_ERROR, "%s: node %u went down while sending "
 939                              "recovery all-done for dead node %u, ret=%d\n",
 940                              dlm->name, reco_master, dead_node, ret);
 941                 }
 942         }
 943 leave:
 944         free_page((unsigned long)data);
 945 }
 946
 947
 948 static int dlm_send_all_done_msg(struct dlm_ctxt *dlm, u8 dead_node, u8 send_to)
 949 {
 950         int ret, tmpret;
 951         struct dlm_reco_data_done done_msg;
 952
 953         memset(&done_msg, 0, sizeof(done_msg));
 954         done_msg.node_idx = dlm->node_num;
 955         done_msg.dead_node = dead_node;
 956         mlog(0, "sending DATA DONE message to %u, "
 957              "my node=%u, dead node=%u\n", send_to, done_msg.node_idx,
 958              done_msg.dead_node);
 959
 960         ret = o2net_send_message(DLM_RECO_DATA_DONE_MSG, dlm->key, &done_msg,
 961                                  sizeof(done_msg), send_to, &tmpret);
 962         if (ret < 0) {
 963                 mlog(ML_ERROR, "%s: Error %d send RECO_DATA_DONE to node %u "
 964                      "to recover dead node %u\n", dlm->name, ret, send_to,
 965                      dead_node);
 966                 if (!dlm_is_host_down(ret)) {
 967                         BUG();
 968                 }
 969         } else
 970                 ret = tmpret;
 971         return ret;
 972 }
 973
 974
 975 int dlm_reco_data_done_handler(struct o2net_msg *msg, u32 len, void *data,
 976                                void **ret_data)
 977 {
 978         struct dlm_ctxt *dlm = data;
 979         struct dlm_reco_data_done *done = (struct dlm_reco_data_done *)msg->buf;
 980         struct dlm_reco_node_data *ndata = NULL;
 981         int ret = -EINVAL;
 982
 983         if (!dlm_grab(dlm))
 984                 return -EINVAL;
 985
 986         mlog(0, "got DATA DONE: dead_node=%u, reco.dead_node=%u, "
 987              "node_idx=%u, this node=%u\n", done->dead_node,
 988              dlm->reco.dead_node, done->node_idx, dlm->node_num);
 989
 990         mlog_bug_on_msg((done->dead_node != dlm->reco.dead_node),
 991                         "Got DATA DONE: dead_node=%u, reco.dead_node=%u, "
 992                         "node_idx=%u, this node=%u\n", done->dead_node,
 993                         dlm->reco.dead_node, done->node_idx, dlm->node_num);
 994
 995         spin_lock(&dlm_reco_state_lock);
 996         list_for_each_entry(ndata, &dlm->reco.node_data, list) {
 997                 if (ndata->node_num != done->node_idx)
 998                         continue;
 999
1000                 switch (ndata->state) {
1001                         /* should have moved beyond INIT but not to FINALIZE yet */
1002                         case DLM_RECO_NODE_DATA_INIT:
1003                         case DLM_RECO_NODE_DATA_DEAD:
1004                         case DLM_RECO_NODE_DATA_FINALIZE_SENT:
1005                                 mlog(ML_ERROR, "bad ndata state for node %u:"
1006                                      " state=%d\n", ndata->node_num,
1007                                      ndata->state);
1008                                 BUG();
1009                                 break;
1010                         /* these states are possible at this point, anywhere along
1011                          * the line of recovery */
1012                         case DLM_RECO_NODE_DATA_DONE:
1013                         case DLM_RECO_NODE_DATA_RECEIVING:
1014                         case DLM_RECO_NODE_DATA_REQUESTED:
1015                         case DLM_RECO_NODE_DATA_REQUESTING:
1016                                 mlog(0, "node %u is DONE sending "
1017                                           "recovery data!\n",
1018                                           ndata->node_num);
1019
1020                                 ndata->state = DLM_RECO_NODE_DATA_DONE;
1021                                 ret = 0;
1022                                 break;
1023                 }
1024         }
1025         spin_unlock(&dlm_reco_state_lock);
1026
1027         /* wake the recovery thread, some node is done */
1028         if (!ret)
1029                 dlm_kick_recovery_thread(dlm);
1030
1031         if (ret < 0)
1032                 mlog(ML_ERROR, "failed to find recovery node data for node "
1033                      "%u\n", done->node_idx);
1034         dlm_put(dlm);
1035
1036         mlog(0, "leaving reco data done handler, ret=%d\n", ret);
1037         return ret;
1038 }
1039
1040 static void dlm_move_reco_locks_to_list(struct dlm_ctxt *dlm,
1041                                         struct list_head *list,
1042                                         u8 dead_node)
1043 {
1044         struct dlm_lock_resource *res, *next;
1045         struct dlm_lock *lock;
1046
1047         spin_lock(&dlm->spinlock);
1048         list_for_each_entry_safe(res, next, &dlm->reco.resources, recovering) {
1049                 /* always prune any $RECOVERY entries for dead nodes,
1050                  * otherwise hangs can occur during later recovery */
1051                 if (dlm_is_recovery_lock(res->lockname.name,
1052                                          res->lockname.len)) {
1053                         spin_lock(&res->spinlock);
1054                         list_for_each_entry(lock, &res->granted, list) {
1055                                 if (lock->ml.node == dead_node) {
1056                                         mlog(0, "AHA! there was "
1057                                              "a $RECOVERY lock for dead "
1058                                              "node %u (%s)!\n",
1059                                              dead_node, dlm->name);
1060                                         list_del_init(&lock->list);
1061                                         dlm_lock_put(lock);
1062                                         break;
1063                                 }
1064                         }
1065                         spin_unlock(&res->spinlock);
1066                         continue;
1067                 }
1068
1069                 if (res->owner == dead_node) {
1070                         mlog(0, "found lockres owned by dead node while "
1071                                   "doing recovery for node %u. sending it.\n",
1072                                   dead_node);
1073                         list_move_tail(&res->recovering, list);
1074                 } else if (res->owner == DLM_LOCK_RES_OWNER_UNKNOWN) {
1075                         mlog(0, "found UNKNOWN owner while doing recovery "
1076                                   "for node %u. sending it.\n", dead_node);
1077                         list_move_tail(&res->recovering, list);
1078                 }
1079         }
1080         spin_unlock(&dlm->spinlock);
1081 }
1082
1083 static inline int dlm_num_locks_in_lockres(struct dlm_lock_resource *res)
1084 {
1085         int total_locks = 0;
1086         struct list_head *iter, *queue = &res->granted;
1087         int i;
1088
1089         for (i=0; i<3; i++) {
1090                 list_for_each(iter, queue)
1091                         total_locks++;
1092                 queue++;
1093         }
1094         return total_locks;
1095 }
1096
1097
1098 static int dlm_send_mig_lockres_msg(struct dlm_ctxt *dlm,
1099                                       struct dlm_migratable_lockres *mres,
1100                                       u8 send_to,
1101                                       struct dlm_lock_resource *res,
1102                                       int total_locks)
1103 {
1104         u64 mig_cookie = be64_to_cpu(mres->mig_cookie);
1105         int mres_total_locks = be32_to_cpu(mres->total_locks);
1106         int sz, ret = 0, status = 0;
1107         u8 orig_flags = mres->flags,
1108            orig_master = mres->master;
1109
1110         BUG_ON(mres->num_locks > DLM_MAX_MIGRATABLE_LOCKS);
1111         if (!mres->num_locks)
1112                 return 0;
1113
1114         sz = sizeof(struct dlm_migratable_lockres) +
1115                 (mres->num_locks * sizeof(struct dlm_migratable_lock));
1116
1117         /* add an all-done flag if we reached the last lock */
1118         orig_flags = mres->flags;
1119         BUG_ON(total_locks > mres_total_locks);
1120         if (total_locks == mres_total_locks)
1121                 mres->flags |= DLM_MRES_ALL_DONE;
1122
1123         mlog(0, "%s:%.*s: sending mig lockres (%s) to %u\n",
1124              dlm->name, res->lockname.len, res->lockname.name,
1125              orig_flags & DLM_MRES_MIGRATION ? "migration" : "recovery",
1126              send_to);
1127
1128         /* send it */
1129         ret = o2net_send_message(DLM_MIG_LOCKRES_MSG, dlm->key, mres,
1130                                  sz, send_to, &status);
1131         if (ret < 0) {
1132                 /* XXX: negative status is not handled.
1133                  * this will end up killing this node. */
1134                 mlog(ML_ERROR, "%s: res %.*s, Error %d send MIG_LOCKRES to "
1135                      "node %u (%s)\n", dlm->name, mres->lockname_len,
1136                      mres->lockname, ret, send_to,
1137                      (orig_flags & DLM_MRES_MIGRATION ?
1138                       "migration" : "recovery"));
1139         } else {
1140                 /* might get an -ENOMEM back here */
1141                 ret = status;
1142                 if (ret < 0) {
1143                         mlog_errno(ret);
1144
1145                         if (ret == -EFAULT) {
1146                                 mlog(ML_ERROR, "node %u told me to kill "
1147                                      "myself!\n", send_to);
1148                                 BUG();
1149                         }
1150                 }
1151         }
1152
1153         /* zero and reinit the message buffer */
1154         dlm_init_migratable_lockres(mres, res->lockname.name,
1155                                     res->lockname.len, mres_total_locks,
1156                                     mig_cookie, orig_flags, orig_master);
1157         return ret;
1158 }
1159
1160 static void dlm_init_migratable_lockres(struct dlm_migratable_lockres *mres,
1161                                         const char *lockname, int namelen,
1162                                         int total_locks, u64 cookie,
1163                                         u8 flags, u8 master)
1164 {
1165         /* mres here is one full page */
1166         clear_page(mres);
1167         mres->lockname_len = namelen;
1168         memcpy(mres->lockname, lockname, namelen);
1169         mres->num_locks = 0;
1170         mres->total_locks = cpu_to_be32(total_locks);
1171         mres->mig_cookie = cpu_to_be64(cookie);
1172         mres->flags = flags;
1173         mres->master = master;
1174 }
1175
1176 static void dlm_prepare_lvb_for_migration(struct dlm_lock *lock,
1177                                           struct dlm_migratable_lockres *mres,
1178                                           int queue)
1179 {
1180         if (!lock->lksb)
1181                return;
1182
1183         /* Ignore lvb in all locks in the blocked list */
1184         if (queue == DLM_BLOCKED_LIST)
1185                 return;
1186
1187         /* Only consider lvbs in locks with granted EX or PR lock levels */
1188         if (lock->ml.type != LKM_EXMODE && lock->ml.type != LKM_PRMODE)
1189                 return;
1190
1191         if (dlm_lvb_is_empty(mres->lvb)) {
1192                 memcpy(mres->lvb, lock->lksb->lvb, DLM_LVB_LEN);
1193                 return;
1194         }
1195
1196         /* Ensure the lvb copied for migration matches in other valid locks */
1197         if (!memcmp(mres->lvb, lock->lksb->lvb, DLM_LVB_LEN))
1198                 return;
1199
1200         mlog(ML_ERROR, "Mismatched lvb in lock cookie=%u:%llu, name=%.*s, "
1201              "node=%u\n",
1202              dlm_get_lock_cookie_node(be64_to_cpu(lock->ml.cookie)),
1203              dlm_get_lock_cookie_seq(be64_to_cpu(lock->ml.cookie)),
1204              lock->lockres->lockname.len, lock->lockres->lockname.name,
1205              lock->ml.node);
1206         dlm_print_one_lock_resource(lock->lockres);
1207         BUG();
1208 }
1209
1210 /* returns 1 if this lock fills the network structure,
1211  * 0 otherwise */
1212 static int dlm_add_lock_to_array(struct dlm_lock *lock,
1213                                  struct dlm_migratable_lockres *mres, int queue)
1214 {
1215         struct dlm_migratable_lock *ml;
1216         int lock_num = mres->num_locks;
1217
1218         ml = &(mres->ml[lock_num]);
1219         ml->cookie = lock->ml.cookie;
1220         ml->type = lock->ml.type;
1221         ml->convert_type = lock->ml.convert_type;
1222         ml->highest_blocked = lock->ml.highest_blocked;
1223         ml->list = queue;
1224         if (lock->lksb) {
1225                 ml->flags = lock->lksb->flags;
1226                 dlm_prepare_lvb_for_migration(lock, mres, queue);
1227         }
1228         ml->node = lock->ml.node;
1229         mres->num_locks++;
1230         /* we reached the max, send this network message */
1231         if (mres->num_locks == DLM_MAX_MIGRATABLE_LOCKS)
1232                 return 1;
1233         return 0;
1234 }
1235
1236 static void dlm_add_dummy_lock(struct dlm_ctxt *dlm,
1237                                struct dlm_migratable_lockres *mres)
1238 {
1239         struct dlm_lock dummy;
1240         memset(&dummy, 0, sizeof(dummy));
1241         dummy.ml.cookie = 0;
1242         dummy.ml.type = LKM_IVMODE;
1243         dummy.ml.convert_type = LKM_IVMODE;
1244         dummy.ml.highest_blocked = LKM_IVMODE;
1245         dummy.lksb = NULL;
1246         dummy.ml.node = dlm->node_num;
1247         dlm_add_lock_to_array(&dummy, mres, DLM_BLOCKED_LIST);
1248 }
1249
1250 static inline int dlm_is_dummy_lock(struct dlm_ctxt *dlm,
1251                                     struct dlm_migratable_lock *ml,
1252                                     u8 *nodenum)
1253 {
1254         if (unlikely(ml->cookie == 0 &&
1255             ml->type == LKM_IVMODE &&
1256             ml->convert_type == LKM_IVMODE &&
1257             ml->highest_blocked == LKM_IVMODE &&
1258             ml->list == DLM_BLOCKED_LIST)) {
1259                 *nodenum = ml->node;
1260                 return 1;
1261         }
1262         return 0;
1263 }
1264
1265 int dlm_send_one_lockres(struct dlm_ctxt *dlm, struct dlm_lock_resource *res,
1266                          struct dlm_migratable_lockres *mres,
1267                          u8 send_to, u8 flags)
1268 {
1269         struct list_head *queue;
1270         int total_locks, i;
1271         u64 mig_cookie = 0;
1272         struct dlm_lock *lock;
1273         int ret = 0;
1274
1275         BUG_ON(!(flags & (DLM_MRES_RECOVERY|DLM_MRES_MIGRATION)));
1276
1277         mlog(0, "sending to %u\n", send_to);
1278
1279         total_locks = dlm_num_locks_in_lockres(res);
1280         if (total_locks > DLM_MAX_MIGRATABLE_LOCKS) {
1281                 /* rare, but possible */
1282                 mlog(0, "argh.  lockres has %d locks.  this will "
1283                           "require more than one network packet to "
1284                           "migrate\n", total_locks);
1285                 mig_cookie = dlm_get_next_mig_cookie();
1286         }
1287
1288         dlm_init_migratable_lockres(mres, res->lockname.name,
1289                                     res->lockname.len, total_locks,
1290                                     mig_cookie, flags, res->owner);
1291
1292         total_locks = 0;
1293         for (i=DLM_GRANTED_LIST; i<=DLM_BLOCKED_LIST; i++) {
1294                 queue = dlm_list_idx_to_ptr(res, i);
1295                 list_for_each_entry(lock, queue, list) {
1296                         /* add another lock. */
1297                         total_locks++;
1298                         if (!dlm_add_lock_to_array(lock, mres, i))
1299                                 continue;
1300
1301                         /* this filled the lock message,
1302                          * we must send it immediately. */
1303                         ret = dlm_send_mig_lockres_msg(dlm, mres, send_to,
1304                                                        res, total_locks);
1305                         if (ret < 0)
1306                                 goto error;
1307                 }
1308         }
1309         if (total_locks == 0) {
1310                 /* send a dummy lock to indicate a mastery reference only */
1311                 mlog(0, "%s:%.*s: sending dummy lock to %u, %s\n",
1312                      dlm->name, res->lockname.len, res->lockname.name,
1313                      send_to, flags & DLM_MRES_RECOVERY ? "recovery" :
1314                      "migration");
1315                 dlm_add_dummy_lock(dlm, mres);
1316         }
1317         /* flush any remaining locks */
1318         ret = dlm_send_mig_lockres_msg(dlm, mres, send_to, res, total_locks);
1319         if (ret < 0)
1320                 goto error;
1321         return ret;
1322
1323 error:
1324         mlog(ML_ERROR, "%s: dlm_send_mig_lockres_msg returned %d\n",
1325              dlm->name, ret);
1326         if (!dlm_is_host_down(ret))
1327                 BUG();
1328         mlog(0, "%s: node %u went down while sending %s "
1329              "lockres %.*s\n", dlm->name, send_to,
1330              flags & DLM_MRES_RECOVERY ?  "recovery" : "migration",
1331              res->lockname.len, res->lockname.name);
1332         return ret;
1333 }
1334
1335
1336
1337 /*
1338  * this message will contain no more than one page worth of
1339  * recovery data, and it will work on only one lockres.
1340  * there may be many locks in this page, and we may need to wait
1341  * for additional packets to complete all the locks (rare, but
1342  * possible).
1343  */
1344 /*
1345  * NOTE: the allocation error cases here are scary
1346  * we really cannot afford to fail an alloc in recovery
1347  * do we spin?  returning an error only delays the problem really
1348  */
1349
1350 int dlm_mig_lockres_handler(struct o2net_msg *msg, u32 len, void *data,
1351                             void **ret_data)
1352 {
1353         struct dlm_ctxt *dlm = data;
1354         struct dlm_migratable_lockres *mres =
1355                 (struct dlm_migratable_lockres *)msg->buf;
1356         int ret = 0;
1357         u8 real_master;
1358         u8 extra_refs = 0;
1359         char *buf = NULL;
1360         struct dlm_work_item *item = NULL;
1361         struct dlm_lock_resource *res = NULL;
1362
1363         if (!dlm_grab(dlm))
1364                 return -EINVAL;
1365
1366         BUG_ON(!(mres->flags & (DLM_MRES_RECOVERY|DLM_MRES_MIGRATION)));
1367
1368         real_master = mres->master;
1369         if (real_master == DLM_LOCK_RES_OWNER_UNKNOWN) {
1370                 /* cannot migrate a lockres with no master */
1371                 BUG_ON(!(mres->flags & DLM_MRES_RECOVERY));
1372         }
1373
1374         mlog(0, "%s message received from node %u\n",
1375                   (mres->flags & DLM_MRES_RECOVERY) ?
1376                   "recovery" : "migration", mres->master);
1377         if (mres->flags & DLM_MRES_ALL_DONE)
1378                 mlog(0, "all done flag.  all lockres data received!\n");
1379
1380         ret = -ENOMEM;
1381         buf = kmalloc(be16_to_cpu(msg->data_len), GFP_NOFS);
1382         item = kzalloc(sizeof(*item), GFP_NOFS);
1383         if (!buf || !item)
1384                 goto leave;
1385
1386         /* lookup the lock to see if we have a secondary queue for this
1387          * already...  just add the locks in and this will have its owner
1388          * and RECOVERY flag changed when it completes. */
1389         res = dlm_lookup_lockres(dlm, mres->lockname, mres->lockname_len);
1390         if (res) {
1391                 /* this will get a ref on res */
1392                 /* mark it as recovering/migrating and hash it */
1393                 spin_lock(&res->spinlock);
1394                 if (mres->flags & DLM_MRES_RECOVERY) {
1395                         res->state |= DLM_LOCK_RES_RECOVERING;
1396                 } else {
1397                         if (res->state & DLM_LOCK_RES_MIGRATING) {
1398                                 /* this is at least the second
1399                                  * lockres message */
1400                                 mlog(0, "lock %.*s is already migrating\n",
1401                                           mres->lockname_len,
1402                                           mres->lockname);
1403                         } else if (res->state & DLM_LOCK_RES_RECOVERING) {
1404                                 /* caller should BUG */
1405                                 mlog(ML_ERROR, "node is attempting to migrate "
1406                                      "lock %.*s, but marked as recovering!\n",
1407                                      mres->lockname_len, mres->lockname);
1408                                 ret = -EFAULT;
1409                                 spin_unlock(&res->spinlock);
1410                                 dlm_lockres_put(res);
1411                                 goto leave;
1412                         }
1413                         res->state |= DLM_LOCK_RES_MIGRATING;
1414                 }
1415                 spin_unlock(&res->spinlock);
1416         } else {
1417                 /* need to allocate, just like if it was
1418                  * mastered here normally  */
1419                 res = dlm_new_lockres(dlm, mres->lockname, mres->lockname_len);
1420                 if (!res)
1421                         goto leave;
1422
1423                 /* to match the ref that we would have gotten if
1424                  * dlm_lookup_lockres had succeeded */
1425                 dlm_lockres_get(res);
1426
1427                 /* mark it as recovering/migrating and hash it */
1428                 if (mres->flags & DLM_MRES_RECOVERY)
1429                         res->state |= DLM_LOCK_RES_RECOVERING;
1430                 else
1431                         res->state |= DLM_LOCK_RES_MIGRATING;
1432
1433                 spin_lock(&dlm->spinlock);
1434                 __dlm_insert_lockres(dlm, res);
1435                 spin_unlock(&dlm->spinlock);
1436
1437                 /* Add an extra ref for this lock-less lockres lest the
1438                  * dlm_thread purges it before we get the chance to add
1439                  * locks to it */
1440                 dlm_lockres_get(res);
1441
1442                 /* There are three refs that need to be put.
1443                  * 1. Taken above.
1444                  * 2. kref_init in dlm_new_lockres()->dlm_init_lockres().
1445                  * 3. dlm_lookup_lockres()
1446                  * The first one is handled at the end of this function. The
1447                  * other two are handled in the worker thread after locks have
1448                  * been attached. Yes, we don't wait for purge time to match
1449                  * kref_init. The lockres will still have atleast one ref
1450                  * added because it is in the hash __dlm_insert_lockres() */
1451                 extra_refs++;
1452
1453                 /* now that the new lockres is inserted,
1454                  * make it usable by other processes */
1455                 spin_lock(&res->spinlock);
1456                 res->state &= ~DLM_LOCK_RES_IN_PROGRESS;
1457                 spin_unlock(&res->spinlock);
1458                 wake_up(&res->wq);
1459         }
1460
1461         /* at this point we have allocated everything we need,
1462          * and we have a hashed lockres with an extra ref and
1463          * the proper res->state flags. */
1464         ret = 0;
1465         spin_lock(&res->spinlock);
1466         /* drop this either when master requery finds a different master
1467          * or when a lock is added by the recovery worker */
1468         dlm_lockres_grab_inflight_ref(dlm, res);
1469         if (mres->master == DLM_LOCK_RES_OWNER_UNKNOWN) {
1470                 /* migration cannot have an unknown master */
1471                 BUG_ON(!(mres->flags & DLM_MRES_RECOVERY));
1472                 mlog(0, "recovery has passed me a lockres with an "
1473                           "unknown owner.. will need to requery: "
1474                           "%.*s\n", mres->lockname_len, mres->lockname);
1475         } else {
1476                 /* take a reference now to pin the lockres, drop it
1477                  * when locks are added in the worker */
1478                 dlm_change_lockres_owner(dlm, res, dlm->node_num);
1479         }
1480         spin_unlock(&res->spinlock);
1481
1482         /* queue up work for dlm_mig_lockres_worker */
1483         dlm_grab(dlm);  /* get an extra ref for the work item */
1484         memcpy(buf, msg->buf, be16_to_cpu(msg->data_len));  /* copy the whole message */
1485         dlm_init_work_item(dlm, item, dlm_mig_lockres_worker, buf);
1486         item->u.ml.lockres = res; /* already have a ref */
1487         item->u.ml.real_master = real_master;
1488         item->u.ml.extra_ref = extra_refs;
1489         spin_lock(&dlm->work_lock);
1490         list_add_tail(&item->list, &dlm->work_list);
1491         spin_unlock(&dlm->work_lock);
1492         queue_work(dlm->dlm_worker, &dlm->dispatched_work);
1493
1494 leave:
1495         /* One extra ref taken needs to be put here */
1496         if (extra_refs)
1497                 dlm_lockres_put(res);
1498
1499         dlm_put(dlm);
1500         if (ret < 0) {
1501                 kfree(buf);
1502                 kfree(item);
1503                 mlog_errno(ret);
1504         }
1505
1506         return ret;
1507 }
1508
1509
1510 static void dlm_mig_lockres_worker(struct dlm_work_item *item, void *data)
1511 {
1512         struct dlm_ctxt *dlm;
1513         struct dlm_migratable_lockres *mres;
1514         int ret = 0;
1515         struct dlm_lock_resource *res;
1516         u8 real_master;
1517         u8 extra_ref;
1518
1519         dlm = item->dlm;
1520         mres = (struct dlm_migratable_lockres *)data;
1521
1522         res = item->u.ml.lockres;
1523         real_master = item->u.ml.real_master;
1524         extra_ref = item->u.ml.extra_ref;
1525
1526         if (real_master == DLM_LOCK_RES_OWNER_UNKNOWN) {
1527                 /* this case is super-rare. only occurs if
1528                  * node death happens during migration. */
1529 again:
1530                 ret = dlm_lockres_master_requery(dlm, res, &real_master);
1531                 if (ret < 0) {
1532                         mlog(0, "dlm_lockres_master_requery ret=%d\n",
1533                                   ret);
1534                         goto again;
1535                 }
1536                 if (real_master == DLM_LOCK_RES_OWNER_UNKNOWN) {
1537                         mlog(0, "lockres %.*s not claimed.  "
1538                                    "this node will take it.\n",
1539                                    res->lockname.len, res->lockname.name);
1540                 } else {
1541                         spin_lock(&res->spinlock);
1542                         dlm_lockres_drop_inflight_ref(dlm, res);
1543                         spin_unlock(&res->spinlock);
1544                         mlog(0, "master needs to respond to sender "
1545                                   "that node %u still owns %.*s\n",
1546                                   real_master, res->lockname.len,
1547                                   res->lockname.name);
1548                         /* cannot touch this lockres */
1549                         goto leave;
1550                 }
1551         }
1552
1553         ret = dlm_process_recovery_data(dlm, res, mres);
1554         if (ret < 0)
1555                 mlog(0, "dlm_process_recovery_data returned  %d\n", ret);
1556         else
1557                 mlog(0, "dlm_process_recovery_data succeeded\n");
1558
1559         if ((mres->flags & (DLM_MRES_MIGRATION|DLM_MRES_ALL_DONE)) ==
1560                            (DLM_MRES_MIGRATION|DLM_MRES_ALL_DONE)) {
1561                 ret = dlm_finish_migration(dlm, res, mres->master);
1562                 if (ret < 0)
1563                         mlog_errno(ret);
1564         }
1565
1566 leave:
1567         /* See comment in dlm_mig_lockres_handler() */
1568         if (res) {
1569                 if (extra_ref)
1570                         dlm_lockres_put(res);
1571                 dlm_lockres_put(res);
1572         }
1573         kfree(data);
1574 }
1575
1576
1577
1578 static int dlm_lockres_master_requery(struct dlm_ctxt *dlm,
1579                                       struct dlm_lock_resource *res,
1580                                       u8 *real_master)
1581 {
1582         struct dlm_node_iter iter;
1583         int nodenum;
1584         int ret = 0;
1585
1586         *real_master = DLM_LOCK_RES_OWNER_UNKNOWN;
1587
1588         /* we only reach here if one of the two nodes in a
1589          * migration died while the migration was in progress.
1590          * at this point we need to requery the master.  we
1591          * know that the new_master got as far as creating
1592          * an mle on at least one node, but we do not know
1593          * if any nodes had actually cleared the mle and set
1594          * the master to the new_master.  the old master
1595          * is supposed to set the owner to UNKNOWN in the
1596          * event of a new_master death, so the only possible
1597          * responses that we can get from nodes here are
1598          * that the master is new_master, or that the master
1599          * is UNKNOWN.
1600          * if all nodes come back with UNKNOWN then we know
1601          * the lock needs remastering here.
1602          * if any node comes back with a valid master, check
1603          * to see if that master is the one that we are
1604          * recovering.  if so, then the new_master died and
1605          * we need to remaster this lock.  if not, then the
1606          * new_master survived and that node will respond to
1607          * other nodes about the owner.
1608          * if there is an owner, this node needs to dump this
1609          * lockres and alert the sender that this lockres
1610          * was rejected. */
1611         spin_lock(&dlm->spinlock);
1612         dlm_node_iter_init(dlm->domain_map, &iter);
1613         spin_unlock(&dlm->spinlock);
1614
1615         while ((nodenum = dlm_node_iter_next(&iter)) >= 0) {
1616                 /* do not send to self */
1617                 if (nodenum == dlm->node_num)
1618                         continue;
1619                 ret = dlm_do_master_requery(dlm, res, nodenum, real_master);
1620                 if (ret < 0) {
1621                         mlog_errno(ret);
1622                         if (!dlm_is_host_down(ret))
1623                                 BUG();
1624                         /* host is down, so answer for that node would be
1625                          * DLM_LOCK_RES_OWNER_UNKNOWN.  continue. */
1626                 }
1627                 if (*real_master != DLM_LOCK_RES_OWNER_UNKNOWN) {
1628                         mlog(0, "lock master is %u\n", *real_master);
1629                         break;
1630                 }
1631         }
1632         return ret;
1633 }
1634
1635
1636 int dlm_do_master_requery(struct dlm_ctxt *dlm, struct dlm_lock_resource *res,
1637                           u8 nodenum, u8 *real_master)
1638 {
1639         int ret = -EINVAL;
1640         struct dlm_master_requery req;
1641         int status = DLM_LOCK_RES_OWNER_UNKNOWN;
1642
1643         memset(&req, 0, sizeof(req));
1644         req.node_idx = dlm->node_num;
1645         req.namelen = res->lockname.len;
1646         memcpy(req.name, res->lockname.name, res->lockname.len);
1647
1648         ret = o2net_send_message(DLM_MASTER_REQUERY_MSG, dlm->key,
1649                                  &req, sizeof(req), nodenum, &status);
1650         /* XXX: negative status not handled properly here. */
1651         if (ret < 0)
1652                 mlog(ML_ERROR, "Error %d when sending message %u (key "
1653                      "0x%x) to node %u\n", ret, DLM_MASTER_REQUERY_MSG,
1654                      dlm->key, nodenum);
1655         else {
1656                 BUG_ON(status < 0);
1657                 BUG_ON(status > DLM_LOCK_RES_OWNER_UNKNOWN);
1658                 *real_master = (u8) (status & 0xff);
1659                 mlog(0, "node %u responded to master requery with %u\n",
1660                           nodenum, *real_master);
1661                 ret = 0;
1662         }
1663         return ret;
1664 }
1665
1666
1667 /* this function cannot error, so unless the sending
1668  * or receiving of the message failed, the owner can
1669  * be trusted */
1670 int dlm_master_requery_handler(struct o2net_msg *msg, u32 len, void *data,
1671                                void **ret_data)
1672 {
1673         struct dlm_ctxt *dlm = data;
1674         struct dlm_master_requery *req = (struct dlm_master_requery *)msg->buf;
1675         struct dlm_lock_resource *res = NULL;
1676         unsigned int hash;
1677         int master = DLM_LOCK_RES_OWNER_UNKNOWN;
1678         u32 flags = DLM_ASSERT_MASTER_REQUERY;
1679
1680         if (!dlm_grab(dlm)) {
1681                 /* since the domain has gone away on this
1682                  * node, the proper response is UNKNOWN */
1683                 return master;
1684         }
1685
1686         hash = dlm_lockid_hash(req->name, req->namelen);
1687
1688         spin_lock(&dlm->spinlock);
1689         res = __dlm_lookup_lockres(dlm, req->name, req->namelen, hash);
1690         if (res) {
1691                 spin_lock(&res->spinlock);
1692                 master = res->owner;
1693                 if (master == dlm->node_num) {
1694                         int ret = dlm_dispatch_assert_master(dlm, res,
1695                                                              0, 0, flags);
1696                         if (ret < 0) {
1697                                 mlog_errno(-ENOMEM);
1698                                 /* retry!? */
1699                                 BUG();
1700                         }
1701                 } else /* put.. incase we are not the master */
1702                         dlm_lockres_put(res);
1703                 spin_unlock(&res->spinlock);
1704         }
1705         spin_unlock(&dlm->spinlock);
1706
1707         dlm_put(dlm);
1708         return master;
1709 }
1710
1711 static inline struct list_head *
1712 dlm_list_num_to_pointer(struct dlm_lock_resource *res, int list_num)
1713 {
1714         struct list_head *ret;
1715         BUG_ON(list_num < 0);
1716         BUG_ON(list_num > 2);
1717         ret = &(res->granted);
1718         ret += list_num;
1719         return ret;
1720 }
1721 /* TODO: do ast flush business
1722  * TODO: do MIGRATING and RECOVERING spinning
1723  */
1724
1725 /*
1726 * NOTE about in-flight requests during migration:
1727 *
1728 * Before attempting the migrate, the master has marked the lockres as
1729 * MIGRATING and then flushed all of its pending ASTS.  So any in-flight
1730 * requests either got queued before the MIGRATING flag got set, in which
1731 * case the lock data will reflect the change and a return message is on
1732 * the way, or the request failed to get in before MIGRATING got set.  In
1733 * this case, the caller will be told to spin and wait for the MIGRATING
1734 * flag to be dropped, then recheck the master.
1735 * This holds true for the convert, cancel and unlock cases, and since lvb
1736 * updates are tied to these same messages, it applies to lvb updates as
1737 * well.  For the lock case, there is no way a lock can be on the master
1738 * queue and not be on the secondary queue since the lock is always added
1739 * locally first.  This means that the new target node will never be sent
1740 * a lock that he doesn't already have on the list.
1741 * In total, this means that the local lock is correct and should not be
1742 * updated to match the one sent by the master.  Any messages sent back
1743 * from the master before the MIGRATING flag will bring the lock properly
1744 * up-to-date, and the change will be ordered properly for the waiter.
1745 * We will *not* attempt to modify the lock underneath the waiter.
1746 */
1747
1748 static int dlm_process_recovery_data(struct dlm_ctxt *dlm,
1749                                      struct dlm_lock_resource *res,
1750                                      struct dlm_migratable_lockres *mres)
1751 {
1752         struct dlm_migratable_lock *ml;
1753         struct list_head *queue;
1754         struct list_head *tmpq = NULL;
1755         struct dlm_lock *newlock = NULL;
1756         struct dlm_lockstatus *lksb = NULL;
1757         int ret = 0;
1758         int i, j, bad;
1759         struct dlm_lock *lock = NULL;
1760         u8 from = O2NM_MAX_NODES;
1761         unsigned int added = 0;
1762         __be64 c;
1763
1764         mlog(0, "running %d locks for this lockres\n", mres->num_locks);
1765         for (i=0; i<mres->num_locks; i++) {
1766                 ml = &(mres->ml[i]);
1767
1768                 if (dlm_is_dummy_lock(dlm, ml, &from)) {
1769                         /* placeholder, just need to set the refmap bit */
1770                         BUG_ON(mres->num_locks != 1);
1771                         mlog(0, "%s:%.*s: dummy lock for %u\n",
1772                              dlm->name, mres->lockname_len, mres->lockname,
1773                              from);
1774                         spin_lock(&res->spinlock);
1775                         dlm_lockres_set_refmap_bit(dlm, res, from);
1776                         spin_unlock(&res->spinlock);
1777                         added++;
1778                         break;
1779                 }
1780                 BUG_ON(ml->highest_blocked != LKM_IVMODE);
1781                 newlock = NULL;
1782                 lksb = NULL;
1783
1784                 queue = dlm_list_num_to_pointer(res, ml->list);
1785                 tmpq = NULL;
1786
1787                 /* if the lock is for the local node it needs to
1788                  * be moved to the proper location within the queue.
1789                  * do not allocate a new lock structure. */
1790                 if (ml->node == dlm->node_num) {
1791                         /* MIGRATION ONLY! */
1792                         BUG_ON(!(mres->flags & DLM_MRES_MIGRATION));
1793
1794                         spin_lock(&res->spinlock);
1795                         for (j = DLM_GRANTED_LIST; j <= DLM_BLOCKED_LIST; j++) {
1796                                 tmpq = dlm_list_idx_to_ptr(res, j);
1797                                 list_for_each_entry(lock, tmpq, list) {
1798                                         if (lock->ml.cookie != ml->cookie)
1799                                                 lock = NULL;
1800                                         else
1801                                                 break;
1802                                 }
1803                                 if (lock)
1804                                         break;
1805                         }
1806
1807                         /* lock is always created locally first, and
1808                          * destroyed locally last.  it must be on the list */
1809                         if (!lock) {
1810                                 c = ml->cookie;
1811                                 mlog(ML_ERROR, "Could not find local lock "
1812                                                "with cookie %u:%llu, node %u, "
1813                                                "list %u, flags 0x%x, type %d, "
1814                                                "conv %d, highest blocked %d\n",
1815                                      dlm_get_lock_cookie_node(be64_to_cpu(c)),
1816                                      dlm_get_lock_cookie_seq(be64_to_cpu(c)),
1817                                      ml->node, ml->list, ml->flags, ml->type,
1818                                      ml->convert_type, ml->highest_blocked);
1819                                 __dlm_print_one_lock_resource(res);
1820                                 BUG();
1821                         }
1822
1823                         if (lock->ml.node != ml->node) {
1824                                 c = lock->ml.cookie;
1825                                 mlog(ML_ERROR, "Mismatched node# in lock "
1826                                      "cookie %u:%llu, name %.*s, node %u\n",
1827                                      dlm_get_lock_cookie_node(be64_to_cpu(c)),
1828                                      dlm_get_lock_cookie_seq(be64_to_cpu(c)),
1829                                      res->lockname.len, res->lockname.name,
1830                                      lock->ml.node);
1831                                 c = ml->cookie;
1832                                 mlog(ML_ERROR, "Migrate lock cookie %u:%llu, "
1833                                      "node %u, list %u, flags 0x%x, type %d, "
1834                                      "conv %d, highest blocked %d\n",
1835                                      dlm_get_lock_cookie_node(be64_to_cpu(c)),
1836                                      dlm_get_lock_cookie_seq(be64_to_cpu(c)),
1837                                      ml->node, ml->list, ml->flags, ml->type,
1838                                      ml->convert_type, ml->highest_blocked);
1839                                 __dlm_print_one_lock_resource(res);
1840                                 BUG();
1841                         }
1842
1843                         if (tmpq != queue) {
1844                                 c = ml->cookie;
1845                                 mlog(0, "Lock cookie %u:%llu was on list %u "
1846                                      "instead of list %u for %.*s\n",
1847                                      dlm_get_lock_cookie_node(be64_to_cpu(c)),
1848                                      dlm_get_lock_cookie_seq(be64_to_cpu(c)),
1849                                      j, ml->list, res->lockname.len,
1850                                      res->lockname.name);
1851                                 __dlm_print_one_lock_resource(res);
1852                                 spin_unlock(&res->spinlock);
1853                                 continue;
1854                         }
1855
1856                         /* see NOTE above about why we do not update
1857                          * to match the master here */
1858
1859                         /* move the lock to its proper place */
1860                         /* do not alter lock refcount.  switching lists. */
1861                         list_move_tail(&lock->list, queue);
1862                         spin_unlock(&res->spinlock);
1863                         added++;
1864
1865                         mlog(0, "just reordered a local lock!\n");
1866                         continue;
1867                 }
1868
1869                 /* lock is for another node. */
1870                 newlock = dlm_new_lock(ml->type, ml->node,
1871                                        be64_to_cpu(ml->cookie), NULL);
1872                 if (!newlock) {
1873                         ret = -ENOMEM;
1874                         goto leave;
1875                 }
1876                 lksb = newlock->lksb;
1877                 dlm_lock_attach_lockres(newlock, res);
1878
1879                 if (ml->convert_type != LKM_IVMODE) {
1880                         BUG_ON(queue != &res->converting);
1881                         newlock->ml.convert_type = ml->convert_type;
1882                 }
1883                 lksb->flags |= (ml->flags &
1884                                 (DLM_LKSB_PUT_LVB|DLM_LKSB_GET_LVB));
1885
1886                 if (ml->type == LKM_NLMODE)
1887                         goto skip_lvb;
1888
1889                 if (!dlm_lvb_is_empty(mres->lvb)) {
1890                         if (lksb->flags & DLM_LKSB_PUT_LVB) {
1891                                 /* other node was trying to update
1892                                  * lvb when node died.  recreate the
1893                                  * lksb with the updated lvb. */
1894                                 memcpy(lksb->lvb, mres->lvb, DLM_LVB_LEN);
1895                                 /* the lock resource lvb update must happen
1896                                  * NOW, before the spinlock is dropped.
1897                                  * we no longer wait for the AST to update
1898                                  * the lvb. */
1899                                 memcpy(res->lvb, mres->lvb, DLM_LVB_LEN);
1900                         } else {
1901                                 /* otherwise, the node is sending its
1902                                  * most recent valid lvb info */
1903                                 BUG_ON(ml->type != LKM_EXMODE &&
1904                                        ml->type != LKM_PRMODE);
1905                                 if (!dlm_lvb_is_empty(res->lvb) &&
1906                                     (ml->type == LKM_EXMODE ||
1907                                      memcmp(res->lvb, mres->lvb, DLM_LVB_LEN))) {
1908                                         int i;
1909                                         mlog(ML_ERROR, "%s:%.*s: received bad "
1910                                              "lvb! type=%d\n", dlm->name,
1911                                              res->lockname.len,
1912                                              res->lockname.name, ml->type);
1913                                         printk("lockres lvb=[");
1914                                         for (i=0; i<DLM_LVB_LEN; i++)
1915                                                 printk("%02x", res->lvb[i]);
1916                                         printk("]\nmigrated lvb=[");
1917                                         for (i=0; i<DLM_LVB_LEN; i++)
1918                                                 printk("%02x", mres->lvb[i]);
1919                                         printk("]\n");
1920                                         dlm_print_one_lock_resource(res);
1921                                         BUG();
1922                                 }
1923                                 memcpy(res->lvb, mres->lvb, DLM_LVB_LEN);
1924                         }
1925                 }
1926 skip_lvb:
1927
1928                 /* NOTE:
1929                  * wrt lock queue ordering and recovery:
1930                  *    1. order of locks on granted queue is
1931                  *       meaningless.
1932                  *    2. order of locks on converting queue is
1933                  *       LOST with the node death.  sorry charlie.
1934                  *    3. order of locks on the blocked queue is
1935                  *       also LOST.
1936                  * order of locks does not affect integrity, it
1937                  * just means that a lock request may get pushed
1938                  * back in line as a result of the node death.
1939                  * also note that for a given node the lock order
1940                  * for its secondary queue locks is preserved
1941                  * relative to each other, but clearly *not*
1942                  * preserved relative to locks from other nodes.
1943                  */
1944                 bad = 0;
1945                 spin_lock(&res->spinlock);
1946                 list_for_each_entry(lock, queue, list) {
1947                         if (lock->ml.cookie == ml->cookie) {
1948                                 c = lock->ml.cookie;
1949                                 mlog(ML_ERROR, "%s:%.*s: %u:%llu: lock already "
1950                                      "exists on this lockres!\n", dlm->name,
1951                                      res->lockname.len, res->lockname.name,
1952                                      dlm_get_lock_cookie_node(be64_to_cpu(c)),
1953                                      dlm_get_lock_cookie_seq(be64_to_cpu(c)));
1954
1955                                 mlog(ML_NOTICE, "sent lock: type=%d, conv=%d, "
1956                                      "node=%u, cookie=%u:%llu, queue=%d\n",
1957                                      ml->type, ml->convert_type, ml->node,
1958                                      dlm_get_lock_cookie_node(be64_to_cpu(ml->cookie)),
1959                                      dlm_get_lock_cookie_seq(be64_to_cpu(ml->cookie)),
1960                                      ml->list);
1961
1962                                 __dlm_print_one_lock_resource(res);
1963                                 bad = 1;
1964                                 break;
1965                         }
1966                 }
1967                 if (!bad) {
1968                         dlm_lock_get(newlock);
1969                         list_add_tail(&newlock->list, queue);
1970                         mlog(0, "%s:%.*s: added lock for node %u, "
1971                              "setting refmap bit\n", dlm->name,
1972                              res->lockname.len, res->lockname.name, ml->node);
1973                         dlm_lockres_set_refmap_bit(dlm, res, ml->node);
1974                         added++;
1975                 }
1976                 spin_unlock(&res->spinlock);
1977         }
1978         mlog(0, "done running all the locks\n");
1979
1980 leave:
1981         /* balance the ref taken when the work was queued */
1982         spin_lock(&res->spinlock);
1983         dlm_lockres_drop_inflight_ref(dlm, res);
1984         spin_unlock(&res->spinlock);
1985
1986         if (ret < 0) {
1987                 mlog_errno(ret);
1988                 if (newlock)
1989                         dlm_lock_put(newlock);
1990         }
1991
1992         return ret;
1993 }
1994
1995 void dlm_move_lockres_to_recovery_list(struct dlm_ctxt *dlm,
1996                                        struct dlm_lock_resource *res)
1997 {
1998         int i;
1999         struct list_head *queue;
2000         struct dlm_lock *lock, *next;
2001
2002         assert_spin_locked(&dlm->spinlock);
2003         assert_spin_locked(&res->spinlock);
2004         res->state |= DLM_LOCK_RES_RECOVERING;
2005         if (!list_empty(&res->recovering)) {
2006                 mlog(0,
2007                      "Recovering res %s:%.*s, is already on recovery list!\n",
2008                      dlm->name, res->lockname.len, res->lockname.name);
2009                 list_del_init(&res->recovering);
2010                 dlm_lockres_put(res);
2011         }
2012         /* We need to hold a reference while on the recovery list */
2013         dlm_lockres_get(res);
2014         list_add_tail(&res->recovering, &dlm->reco.resources);
2015
2016         /* find any pending locks and put them back on proper list */
2017         for (i=DLM_BLOCKED_LIST; i>=DLM_GRANTED_LIST; i--) {
2018                 queue = dlm_list_idx_to_ptr(res, i);
2019                 list_for_each_entry_safe(lock, next, queue, list) {
2020                         dlm_lock_get(lock);
2021                         if (lock->convert_pending) {
2022                                 /* move converting lock back to granted */
2023                                 BUG_ON(i != DLM_CONVERTING_LIST);
2024                                 mlog(0, "node died with convert pending "
2025                                      "on %.*s. move back to granted list.\n",
2026                                      res->lockname.len, res->lockname.name);
2027                                 dlm_revert_pending_convert(res, lock);
2028                                 lock->convert_pending = 0;
2029                         } else if (lock->lock_pending) {
2030                                 /* remove pending lock requests completely */
2031                                 BUG_ON(i != DLM_BLOCKED_LIST);
2032                                 mlog(0, "node died with lock pending "
2033                                      "on %.*s. remove from blocked list and skip.\n",
2034                                      res->lockname.len, res->lockname.name);
2035                                 /* lock will be floating until ref in
2036                                  * dlmlock_remote is freed after the network
2037                                  * call returns.  ok for it to not be on any
2038                                  * list since no ast can be called
2039                                  * (the master is dead). */
2040                                 dlm_revert_pending_lock(res, lock);
2041                                 lock->lock_pending = 0;
2042                         } else if (lock->unlock_pending) {
2043                                 /* if an unlock was in progress, treat as
2044                                  * if this had completed successfully
2045                                  * before sending this lock state to the
2046                                  * new master.  note that the dlm_unlock
2047                                  * call is still responsible for calling
2048                                  * the unlockast.  that will happen after
2049                                  * the network call times out.  for now,
2050                                  * just move lists to prepare the new
2051                                  * recovery master.  */
2052                                 BUG_ON(i != DLM_GRANTED_LIST);
2053                                 mlog(0, "node died with unlock pending "
2054                                      "on %.*s. remove from blocked list and skip.\n",
2055                                      res->lockname.len, res->lockname.name);
2056                                 dlm_commit_pending_unlock(res, lock);
2057                                 lock->unlock_pending = 0;
2058                         } else if (lock->cancel_pending) {
2059                                 /* if a cancel was in progress, treat as
2060                                  * if this had completed successfully
2061                                  * before sending this lock state to the
2062                                  * new master */
2063                                 BUG_ON(i != DLM_CONVERTING_LIST);
2064                                 mlog(0, "node died with cancel pending "
2065                                      "on %.*s. move back to granted list.\n",
2066                                      res->lockname.len, res->lockname.name);
2067                                 dlm_commit_pending_cancel(res, lock);
2068                                 lock->cancel_pending = 0;
2069                         }
2070                         dlm_lock_put(lock);
2071                 }
2072         }
2073 }
2074
2075
2076
2077 /* removes all recovered locks from the recovery list.
2078  * sets the res->owner to the new master.
2079  * unsets the RECOVERY flag and wakes waiters. */
2080 static void dlm_finish_local_lockres_recovery(struct dlm_ctxt *dlm,
2081                                               u8 dead_node, u8 new_master)
2082 {
2083         int i;
2084         struct hlist_head *bucket;
2085         struct dlm_lock_resource *res, *next;
2086
2087         assert_spin_locked(&dlm->spinlock);
2088
2089         list_for_each_entry_safe(res, next, &dlm->reco.resources, recovering) {
2090                 if (res->owner == dead_node) {
2091                         mlog(0, "%s: res %.*s, Changing owner from %u to %u\n",
2092                              dlm->name, res->lockname.len, res->lockname.name,
2093                              res->owner, new_master);
2094                         list_del_init(&res->recovering);
2095                         spin_lock(&res->spinlock);
2096                         /* new_master has our reference from
2097                          * the lock state sent during recovery */
2098                         dlm_change_lockres_owner(dlm, res, new_master);
2099                         res->state &= ~DLM_LOCK_RES_RECOVERING;
2100                         if (__dlm_lockres_has_locks(res))
2101                                 __dlm_dirty_lockres(dlm, res);
2102                         spin_unlock(&res->spinlock);
2103                         wake_up(&res->wq);
2104                         dlm_lockres_put(res);
2105                 }
2106         }
2107
2108         /* this will become unnecessary eventually, but
2109          * for now we need to run the whole hash, clear
2110          * the RECOVERING state and set the owner
2111          * if necessary */
2112         for (i = 0; i < DLM_HASH_BUCKETS; i++) {
2113                 bucket = dlm_lockres_hash(dlm, i);
2114                 hlist_for_each_entry(res, bucket, hash_node) {
2115                         if (!(res->state & DLM_LOCK_RES_RECOVERING))
2116                                 continue;
2117
2118                         if (res->owner != dead_node &&
2119                             res->owner != dlm->node_num)
2120                                 continue;
2121
2122                         if (!list_empty(&res->recovering)) {
2123                                 list_del_init(&res->recovering);
2124                                 dlm_lockres_put(res);
2125                         }
2126
2127                         /* new_master has our reference from
2128                          * the lock state sent during recovery */
2129                         mlog(0, "%s: res %.*s, Changing owner from %u to %u\n",
2130                              dlm->name, res->lockname.len, res->lockname.name,
2131                              res->owner, new_master);
2132                         spin_lock(&res->spinlock);
2133                         dlm_change_lockres_owner(dlm, res, new_master);
2134                         res->state &= ~DLM_LOCK_RES_RECOVERING;
2135                         if (__dlm_lockres_has_locks(res))
2136                                 __dlm_dirty_lockres(dlm, res);
2137                         spin_unlock(&res->spinlock);
2138                         wake_up(&res->wq);
2139                 }
2140         }
2141 }
2142
2143 static inline int dlm_lvb_needs_invalidation(struct dlm_lock *lock, int local)
2144 {
2145         if (local) {
2146                 if (lock->ml.type != LKM_EXMODE &&
2147                     lock->ml.type != LKM_PRMODE)
2148                         return 1;
2149         } else if (lock->ml.type == LKM_EXMODE)
2150                 return 1;
2151         return 0;
2152 }
2153
2154 static void dlm_revalidate_lvb(struct dlm_ctxt *dlm,
2155                                struct dlm_lock_resource *res, u8 dead_node)
2156 {
2157         struct list_head *queue;
2158         struct dlm_lock *lock;
2159         int blank_lvb = 0, local = 0;
2160         int i;
2161         u8 search_node;
2162
2163         assert_spin_locked(&dlm->spinlock);
2164         assert_spin_locked(&res->spinlock);
2165
2166         if (res->owner == dlm->node_num)
2167                 /* if this node owned the lockres, and if the dead node
2168                  * had an EX when he died, blank out the lvb */
2169                 search_node = dead_node;
2170         else {
2171                 /* if this is a secondary lockres, and we had no EX or PR
2172                  * locks granted, we can no longer trust the lvb */
2173                 search_node = dlm->node_num;
2174                 local = 1;  /* check local state for valid lvb */
2175         }
2176
2177         for (i=DLM_GRANTED_LIST; i<=DLM_CONVERTING_LIST; i++) {
2178                 queue = dlm_list_idx_to_ptr(res, i);
2179                 list_for_each_entry(lock, queue, list) {
2180                         if (lock->ml.node == search_node) {
2181                                 if (dlm_lvb_needs_invalidation(lock, local)) {
2182                                         /* zero the lksb lvb and lockres lvb */
2183                                         blank_lvb = 1;
2184                                         memset(lock->lksb->lvb, 0, DLM_LVB_LEN);
2185                                 }
2186                         }
2187                 }
2188         }
2189
2190         if (blank_lvb) {
2191                 mlog(0, "clearing %.*s lvb, dead node %u had EX\n",
2192                      res->lockname.len, res->lockname.name, dead_node);
2193                 memset(res->lvb, 0, DLM_LVB_LEN);
2194         }
2195 }
2196
2197 static void dlm_free_dead_locks(struct dlm_ctxt *dlm,
2198                                 struct dlm_lock_resource *res, u8 dead_node)
2199 {
2200         struct dlm_lock *lock, *next;
2201         unsigned int freed = 0;
2202
2203         /* this node is the lockres master:
2204          * 1) remove any stale locks for the dead node
2205          * 2) if the dead node had an EX when he died, blank out the lvb
2206          */
2207         assert_spin_locked(&dlm->spinlock);
2208         assert_spin_locked(&res->spinlock);
2209
2210         /* We do two dlm_lock_put(). One for removing from list and the other is
2211          * to force the DLM_UNLOCK_FREE_LOCK action so as to free the locks */
2212
2213         /* TODO: check pending_asts, pending_basts here */
2214         list_for_each_entry_safe(lock, next, &res->granted, list) {
2215                 if (lock->ml.node == dead_node) {
2216                         list_del_init(&lock->list);
2217                         dlm_lock_put(lock);
2218                         /* Can't schedule DLM_UNLOCK_FREE_LOCK - do manually */
2219                         dlm_lock_put(lock);
2220                         freed++;
2221                 }
2222         }
2223         list_for_each_entry_safe(lock, next, &res->converting, list) {
2224                 if (lock->ml.node == dead_node) {
2225                         list_del_init(&lock->list);
2226                         dlm_lock_put(lock);
2227                         /* Can't schedule DLM_UNLOCK_FREE_LOCK - do manually */
2228                         dlm_lock_put(lock);
2229                         freed++;
2230                 }
2231         }
2232         list_for_each_entry_safe(lock, next, &res->blocked, list) {
2233                 if (lock->ml.node == dead_node) {
2234                         list_del_init(&lock->list);
2235                         dlm_lock_put(lock);
2236                         /* Can't schedule DLM_UNLOCK_FREE_LOCK - do manually */
2237                         dlm_lock_put(lock);
2238                         freed++;
2239                 }
2240         }
2241
2242         if (freed) {
2243                 mlog(0, "%s:%.*s: freed %u locks for dead node %u, "
2244                      "dropping ref from lockres\n", dlm->name,
2245                      res->lockname.len, res->lockname.name, freed, dead_node);
2246                 if(!test_bit(dead_node, res->refmap)) {
2247                         mlog(ML_ERROR, "%s:%.*s: freed %u locks for dead node %u, "
2248                              "but ref was not set\n", dlm->name,
2249                              res->lockname.len, res->lockname.name, freed, dead_node);
2250                         __dlm_print_one_lock_resource(res);
2251                 }
2252                 dlm_lockres_clear_refmap_bit(dlm, res, dead_node);
2253         } else if (test_bit(dead_node, res->refmap)) {
2254                 mlog(0, "%s:%.*s: dead node %u had a ref, but had "
2255                      "no locks and had not purged before dying\n", dlm->name,
2256                      res->lockname.len, res->lockname.name, dead_node);
2257                 dlm_lockres_clear_refmap_bit(dlm, res, dead_node);
2258         }
2259
2260         /* do not kick thread yet */
2261         __dlm_dirty_lockres(dlm, res);
2262 }
2263
2264 /* if this node is the recovery master, and there are no
2265  * locks for a given lockres owned by this node that are in
2266  * either PR or EX mode, zero out the lvb before requesting.
2267  *
2268  */
2269
2270
2271 static void dlm_do_local_recovery_cleanup(struct dlm_ctxt *dlm, u8 dead_node)
2272 {
2273         struct dlm_lock_resource *res;
2274         int i;
2275         struct hlist_head *bucket;
2276         struct dlm_lock *lock;
2277
2278
2279         /* purge any stale mles */
2280         dlm_clean_master_list(dlm, dead_node);
2281
2282         /*
2283          * now clean up all lock resources.  there are two rules:
2284          *
2285          * 1) if the dead node was the master, move the lockres
2286          *    to the recovering list.  set the RECOVERING flag.
2287          *    this lockres needs to be cleaned up before it can
2288          *    be used further.
2289          *
2290          * 2) if this node was the master, remove all locks from
2291          *    each of the lockres queues that were owned by the
2292          *    dead node.  once recovery finishes, the dlm thread
2293          *    can be kicked again to see if any ASTs or BASTs
2294          *    need to be fired as a result.
2295          */
2296         for (i = 0; i < DLM_HASH_BUCKETS; i++) {
2297                 bucket = dlm_lockres_hash(dlm, i);
2298                 hlist_for_each_entry(res, bucket, hash_node) {
2299                         /* always prune any $RECOVERY entries for dead nodes,
2300                          * otherwise hangs can occur during later recovery */
2301                         if (dlm_is_recovery_lock(res->lockname.name,
2302                                                  res->lockname.len)) {
2303                                 spin_lock(&res->spinlock);
2304                                 list_for_each_entry(lock, &res->granted, list) {
2305                                         if (lock->ml.node == dead_node) {
2306                                                 mlog(0, "AHA! there was "
2307                                                      "a $RECOVERY lock for dead "
2308                                                      "node %u (%s)!\n",
2309                                                      dead_node, dlm->name);
2310                                                 list_del_init(&lock->list);
2311                                                 dlm_lock_put(lock);
2312                                                 break;
2313                                         }
2314                                 }
2315                                 spin_unlock(&res->spinlock);
2316                                 continue;
2317                         }
2318                         spin_lock(&res->spinlock);
2319                         /* zero the lvb if necessary */
2320                         dlm_revalidate_lvb(dlm, res, dead_node);
2321                         if (res->owner == dead_node) {
2322                                 if (res->state & DLM_LOCK_RES_DROPPING_REF) {
2323                                         mlog(ML_NOTICE, "%s: res %.*s, Skip "
2324                                              "recovery as it is being freed\n",
2325                                              dlm->name, res->lockname.len,
2326                                              res->lockname.name);
2327                                 } else
2328                                         dlm_move_lockres_to_recovery_list(dlm,
2329                                                                           res);
2330
2331                         } else if (res->owner == dlm->node_num) {
2332                                 dlm_free_dead_locks(dlm, res, dead_node);
2333                                 __dlm_lockres_calc_usage(dlm, res);
2334                         } else if (res->owner == DLM_LOCK_RES_OWNER_UNKNOWN) {
2335                                 if (test_bit(dead_node, res->refmap)) {
2336                                         mlog(0, "%s:%.*s: dead node %u had a ref, but had "
2337                                                 "no locks and had not purged before dying\n",
2338                                                 dlm->name, res->lockname.len,
2339                                                 res->lockname.name, dead_node);
2340                                         dlm_lockres_clear_refmap_bit(dlm, res, dead_node);
2341                                 }
2342                         }
2343                         spin_unlock(&res->spinlock);
2344                 }
2345         }
2346
2347 }
2348
2349 static void __dlm_hb_node_down(struct dlm_ctxt *dlm, int idx)
2350 {
2351         assert_spin_locked(&dlm->spinlock);
2352
2353         if (dlm->reco.new_master == idx) {
2354                 mlog(0, "%s: recovery master %d just died\n",
2355                      dlm->name, idx);
2356                 if (dlm->reco.state & DLM_RECO_STATE_FINALIZE) {
2357                         /* finalize1 was reached, so it is safe to clear
2358                          * the new_master and dead_node.  that recovery
2359                          * is complete. */
2360                         mlog(0, "%s: dead master %d had reached "
2361                              "finalize1 state, clearing\n", dlm->name, idx);
2362                         dlm->reco.state &= ~DLM_RECO_STATE_FINALIZE;
2363                         __dlm_reset_recovery(dlm);
2364                 }
2365         }
2366
2367         /* Clean up join state on node death. */
2368         if (dlm->joining_node == idx) {
2369                 mlog(0, "Clearing join state for node %u\n", idx);
2370                 __dlm_set_joining_node(dlm, DLM_LOCK_RES_OWNER_UNKNOWN);
2371         }
2372
2373         /* check to see if the node is already considered dead */
2374         if (!test_bit(idx, dlm->live_nodes_map)) {
2375                 mlog(0, "for domain %s, node %d is already dead. "
2376                      "another node likely did recovery already.\n",
2377                      dlm->name, idx);
2378                 return;
2379         }
2380
2381         /* check to see if we do not care about this node */
2382         if (!test_bit(idx, dlm->domain_map)) {
2383                 /* This also catches the case that we get a node down
2384                  * but haven't joined the domain yet. */
2385                 mlog(0, "node %u already removed from domain!\n", idx);
2386                 return;
2387         }
2388
2389         clear_bit(idx, dlm->live_nodes_map);
2390
2391         /* make sure local cleanup occurs before the heartbeat events */
2392         if (!test_bit(idx, dlm->recovery_map))
2393                 dlm_do_local_recovery_cleanup(dlm, idx);
2394
2395         /* notify anything attached to the heartbeat events */
2396         dlm_hb_event_notify_attached(dlm, idx, 0);
2397
2398         mlog(0, "node %u being removed from domain map!\n", idx);
2399         clear_bit(idx, dlm->domain_map);
2400         clear_bit(idx, dlm->exit_domain_map);
2401         /* wake up migration waiters if a node goes down.
2402          * perhaps later we can genericize this for other waiters. */
2403         wake_up(&dlm->migration_wq);
2404
2405         if (test_bit(idx, dlm->recovery_map))
2406                 mlog(0, "domain %s, node %u already added "
2407                      "to recovery map!\n", dlm->name, idx);
2408         else
2409                 set_bit(idx, dlm->recovery_map);
2410 }
2411
2412 void dlm_hb_node_down_cb(struct o2nm_node *node, int idx, void *data)
2413 {
2414         struct dlm_ctxt *dlm = data;
2415
2416         if (!dlm_grab(dlm))
2417                 return;
2418
2419         /*
2420          * This will notify any dlm users that a node in our domain
2421          * went away without notifying us first.
2422          */
2423         if (test_bit(idx, dlm->domain_map))
2424                 dlm_fire_domain_eviction_callbacks(dlm, idx);
2425
2426         spin_lock(&dlm->spinlock);
2427         __dlm_hb_node_down(dlm, idx);
2428         spin_unlock(&dlm->spinlock);
2429
2430         dlm_put(dlm);
2431 }
2432
2433 void dlm_hb_node_up_cb(struct o2nm_node *node, int idx, void *data)
2434 {
2435         struct dlm_ctxt *dlm = data;
2436
2437         if (!dlm_grab(dlm))
2438                 return;
2439
2440         spin_lock(&dlm->spinlock);
2441         set_bit(idx, dlm->live_nodes_map);
2442         /* do NOT notify mle attached to the heartbeat events.
2443          * new nodes are not interesting in mastery until joined. */
2444         spin_unlock(&dlm->spinlock);
2445
2446         dlm_put(dlm);
2447 }
2448
2449 static void dlm_reco_ast(void *astdata)
2450 {
2451         struct dlm_ctxt *dlm = astdata;
2452         mlog(0, "ast for recovery lock fired!, this=%u, dlm=%s\n",
2453              dlm->node_num, dlm->name);
2454 }
2455 static void dlm_reco_bast(void *astdata, int blocked_type)
2456 {
2457         struct dlm_ctxt *dlm = astdata;
2458         mlog(0, "bast for recovery lock fired!, this=%u, dlm=%s\n",
2459              dlm->node_num, dlm->name);
2460 }
2461 static void dlm_reco_unlock_ast(void *astdata, enum dlm_status st)
2462 {
2463         mlog(0, "unlockast for recovery lock fired!\n");
2464 }
2465
2466 /*
2467  * dlm_pick_recovery_master will continually attempt to use
2468  * dlmlock() on the special "$RECOVERY" lockres with the
2469  * LKM_NOQUEUE flag to get an EX.  every thread that enters
2470  * this function on each node racing to become the recovery
2471  * master will not stop attempting this until either:
2472  * a) this node gets the EX (and becomes the recovery master),
2473  * or b) dlm->reco.new_master gets set to some nodenum
2474  * != O2NM_INVALID_NODE_NUM (another node will do the reco).
2475  * so each time a recovery master is needed, the entire cluster
2476  * will sync at this point.  if the new master dies, that will
2477  * be detected in dlm_do_recovery */
2478 static int dlm_pick_recovery_master(struct dlm_ctxt *dlm)
2479 {
2480         enum dlm_status ret;
2481         struct dlm_lockstatus lksb;
2482         int status = -EINVAL;
2483
2484         mlog(0, "starting recovery of %s at %lu, dead=%u, this=%u\n",
2485              dlm->name, jiffies, dlm->reco.dead_node, dlm->node_num);
2486 again:
2487         memset(&lksb, 0, sizeof(lksb));
2488
2489         ret = dlmlock(dlm, LKM_EXMODE, &lksb, LKM_NOQUEUE|LKM_RECOVERY,
2490                       DLM_RECOVERY_LOCK_NAME, DLM_RECOVERY_LOCK_NAME_LEN,
2491                       dlm_reco_ast, dlm, dlm_reco_bast);
2492
2493         mlog(0, "%s: dlmlock($RECOVERY) returned %d, lksb=%d\n",
2494              dlm->name, ret, lksb.status);
2495
2496         if (ret == DLM_NORMAL) {
2497                 mlog(0, "dlm=%s dlmlock says I got it (this=%u)\n",
2498                      dlm->name, dlm->node_num);
2499
2500                 /* got the EX lock.  check to see if another node
2501                  * just became the reco master */
2502                 if (dlm_reco_master_ready(dlm)) {
2503                         mlog(0, "%s: got reco EX lock, but %u will "
2504                              "do the recovery\n", dlm->name,
2505                              dlm->reco.new_master);
2506                         status = -EEXIST;
2507                 } else {
2508                         status = 0;
2509
2510                         /* see if recovery was already finished elsewhere */
2511                         spin_lock(&dlm->spinlock);
2512                         if (dlm->reco.dead_node == O2NM_INVALID_NODE_NUM) {
2513                                 status = -EINVAL;
2514                                 mlog(0, "%s: got reco EX lock, but "
2515                                      "node got recovered already\n", dlm->name);
2516                                 if (dlm->reco.new_master != O2NM_INVALID_NODE_NUM) {
2517                                         mlog(ML_ERROR, "%s: new master is %u "
2518                                              "but no dead node!\n",
2519                                              dlm->name, dlm->reco.new_master);
2520                                         BUG();
2521                                 }
2522                         }
2523                         spin_unlock(&dlm->spinlock);
2524                 }
2525
2526                 /* if this node has actually become the recovery master,
2527                  * set the master and send the messages to begin recovery */
2528                 if (!status) {
2529                         mlog(0, "%s: dead=%u, this=%u, sending "
2530                              "begin_reco now\n", dlm->name,
2531                              dlm->reco.dead_node, dlm->node_num);
2532                         status = dlm_send_begin_reco_message(dlm,
2533                                       dlm->reco.dead_node);
2534                         /* this always succeeds */
2535                         BUG_ON(status);
2536
2537                         /* set the new_master to this node */
2538                         spin_lock(&dlm->spinlock);
2539                         dlm_set_reco_master(dlm, dlm->node_num);
2540                         spin_unlock(&dlm->spinlock);
2541                 }
2542
2543                 /* recovery lock is a special case.  ast will not get fired,
2544                  * so just go ahead and unlock it. */
2545                 ret = dlmunlock(dlm, &lksb, 0, dlm_reco_unlock_ast, dlm);
2546                 if (ret == DLM_DENIED) {
2547                         mlog(0, "got DLM_DENIED, trying LKM_CANCEL\n");
2548                         ret = dlmunlock(dlm, &lksb, LKM_CANCEL, dlm_reco_unlock_ast, dlm);
2549                 }
2550                 if (ret != DLM_NORMAL) {
2551                         /* this would really suck. this could only happen
2552                          * if there was a network error during the unlock
2553                          * because of node death.  this means the unlock
2554                          * is actually "done" and the lock structure is
2555                          * even freed.  we can continue, but only
2556                          * because this specific lock name is special. */
2557                         mlog(ML_ERROR, "dlmunlock returned %d\n", ret);
2558                 }
2559         } else if (ret == DLM_NOTQUEUED) {
2560                 mlog(0, "dlm=%s dlmlock says another node got it (this=%u)\n",
2561                      dlm->name, dlm->node_num);
2562                 /* another node is master. wait on
2563                  * reco.new_master != O2NM_INVALID_NODE_NUM
2564                  * for at most one second */
2565                 wait_event_timeout(dlm->dlm_reco_thread_wq,
2566                                          dlm_reco_master_ready(dlm),
2567                                          msecs_to_jiffies(1000));
2568                 if (!dlm_reco_master_ready(dlm)) {
2569                         mlog(0, "%s: reco master taking awhile\n",
2570                              dlm->name);
2571                         goto again;
2572                 }
2573                 /* another node has informed this one that it is reco master */
2574                 mlog(0, "%s: reco master %u is ready to recover %u\n",
2575                      dlm->name, dlm->reco.new_master, dlm->reco.dead_node);
2576                 status = -EEXIST;
2577         } else if (ret == DLM_RECOVERING) {
2578                 mlog(0, "dlm=%s dlmlock says master node died (this=%u)\n",
2579                      dlm->name, dlm->node_num);
2580                 goto again;
2581         } else {
2582                 struct dlm_lock_resource *res;
2583
2584                 /* dlmlock returned something other than NOTQUEUED or NORMAL */
2585                 mlog(ML_ERROR, "%s: got %s from dlmlock($RECOVERY), "
2586                      "lksb.status=%s\n", dlm->name, dlm_errname(ret),
2587                      dlm_errname(lksb.status));
2588                 res = dlm_lookup_lockres(dlm, DLM_RECOVERY_LOCK_NAME,
2589                                          DLM_RECOVERY_LOCK_NAME_LEN);
2590                 if (res) {
2591                         dlm_print_one_lock_resource(res);
2592                         dlm_lockres_put(res);
2593                 } else {
2594                         mlog(ML_ERROR, "recovery lock not found\n");
2595                 }
2596                 BUG();
2597         }
2598
2599         return status;
2600 }
2601
2602 static int dlm_send_begin_reco_message(struct dlm_ctxt *dlm, u8 dead_node)
2603 {
2604         struct dlm_begin_reco br;
2605         int ret = 0;
2606         struct dlm_node_iter iter;
2607         int nodenum;
2608         int status;
2609
2610         mlog(0, "%s: dead node is %u\n", dlm->name, dead_node);
2611
2612         spin_lock(&dlm->spinlock);
2613         dlm_node_iter_init(dlm->domain_map, &iter);
2614         spin_unlock(&dlm->spinlock);
2615
2616         clear_bit(dead_node, iter.node_map);
2617
2618         memset(&br, 0, sizeof(br));
2619         br.node_idx = dlm->node_num;
2620         br.dead_node = dead_node;
2621
2622         while ((nodenum = dlm_node_iter_next(&iter)) >= 0) {
2623                 ret = 0;
2624                 if (nodenum == dead_node) {
2625                         mlog(0, "not sending begin reco to dead node "
2626                                   "%u\n", dead_node);
2627                         continue;
2628                 }
2629                 if (nodenum == dlm->node_num) {
2630                         mlog(0, "not sending begin reco to self\n");
2631                         continue;
2632                 }
2633 retry:
2634                 ret = -EINVAL;
2635                 mlog(0, "attempting to send begin reco msg to %d\n",
2636                           nodenum);
2637                 ret = o2net_send_message(DLM_BEGIN_RECO_MSG, dlm->key,
2638                                          &br, sizeof(br), nodenum, &status);
2639                 /* negative status is handled ok by caller here */
2640                 if (ret >= 0)
2641                         ret = status;
2642                 if (dlm_is_host_down(ret)) {
2643                         /* node is down.  not involved in recovery
2644                          * so just keep going */
2645                         mlog(ML_NOTICE, "%s: node %u was down when sending "
2646                              "begin reco msg (%d)\n", dlm->name, nodenum, ret);
2647                         ret = 0;
2648                 }
2649
2650                 /*
2651                  * Prior to commit aad1b15310b9bcd59fa81ab8f2b1513b59553ea8,
2652                  * dlm_begin_reco_handler() returned EAGAIN and not -EAGAIN.
2653                  * We are handling both for compatibility reasons.
2654                  */
2655                 if (ret == -EAGAIN || ret == EAGAIN) {
2656                         mlog(0, "%s: trying to start recovery of node "
2657                              "%u, but node %u is waiting for last recovery "
2658                              "to complete, backoff for a bit\n", dlm->name,
2659                              dead_node, nodenum);
2660                         msleep(100);
2661                         goto retry;
2662                 }
2663                 if (ret < 0) {
2664                         struct dlm_lock_resource *res;
2665
2666                         /* this is now a serious problem, possibly ENOMEM
2667                          * in the network stack.  must retry */
2668                         mlog_errno(ret);
2669                         mlog(ML_ERROR, "begin reco of dlm %s to node %u "
2670                              "returned %d\n", dlm->name, nodenum, ret);
2671                         res = dlm_lookup_lockres(dlm, DLM_RECOVERY_LOCK_NAME,
2672                                                  DLM_RECOVERY_LOCK_NAME_LEN);
2673                         if (res) {
2674                                 dlm_print_one_lock_resource(res);
2675                                 dlm_lockres_put(res);
2676                         } else {
2677                                 mlog(ML_ERROR, "recovery lock not found\n");
2678                         }
2679                         /* sleep for a bit in hopes that we can avoid
2680                          * another ENOMEM */
2681                         msleep(100);
2682                         goto retry;
2683                 }
2684         }
2685
2686         return ret;
2687 }
2688
2689 int dlm_begin_reco_handler(struct o2net_msg *msg, u32 len, void *data,
2690                            void **ret_data)
2691 {
2692         struct dlm_ctxt *dlm = data;
2693         struct dlm_begin_reco *br = (struct dlm_begin_reco *)msg->buf;
2694
2695         /* ok to return 0, domain has gone away */
2696         if (!dlm_grab(dlm))
2697                 return 0;
2698
2699         spin_lock(&dlm->spinlock);
2700         if (dlm->reco.state & DLM_RECO_STATE_FINALIZE) {
2701                 mlog(0, "%s: node %u wants to recover node %u (%u:%u) "
2702                      "but this node is in finalize state, waiting on finalize2\n",
2703                      dlm->name, br->node_idx, br->dead_node,
2704                      dlm->reco.dead_node, dlm->reco.new_master);
2705                 spin_unlock(&dlm->spinlock);
2706                 dlm_put(dlm);
2707                 return -EAGAIN;
2708         }
2709         spin_unlock(&dlm->spinlock);
2710
2711         mlog(0, "%s: node %u wants to recover node %u (%u:%u)\n",
2712              dlm->name, br->node_idx, br->dead_node,
2713              dlm->reco.dead_node, dlm->reco.new_master);
2714
2715         dlm_fire_domain_eviction_callbacks(dlm, br->dead_node);
2716
2717         spin_lock(&dlm->spinlock);
2718         if (dlm->reco.new_master != O2NM_INVALID_NODE_NUM) {
2719                 if (test_bit(dlm->reco.new_master, dlm->recovery_map)) {
2720                         mlog(0, "%s: new_master %u died, changing "
2721                              "to %u\n", dlm->name, dlm->reco.new_master,
2722                              br->node_idx);
2723                 } else {
2724                         mlog(0, "%s: new_master %u NOT DEAD, changing "
2725                              "to %u\n", dlm->name, dlm->reco.new_master,
2726                              br->node_idx);
2727                         /* may not have seen the new master as dead yet */
2728                 }
2729         }
2730         if (dlm->reco.dead_node != O2NM_INVALID_NODE_NUM) {
2731                 mlog(ML_NOTICE, "%s: dead_node previously set to %u, "
2732                      "node %u changing it to %u\n", dlm->name,
2733                      dlm->reco.dead_node, br->node_idx, br->dead_node);
2734         }
2735         dlm_set_reco_master(dlm, br->node_idx);
2736         dlm_set_reco_dead_node(dlm, br->dead_node);
2737         if (!test_bit(br->dead_node, dlm->recovery_map)) {
2738                 mlog(0, "recovery master %u sees %u as dead, but this "
2739                      "node has not yet.  marking %u as dead\n",
2740                      br->node_idx, br->dead_node, br->dead_node);
2741                 if (!test_bit(br->dead_node, dlm->domain_map) ||
2742                     !test_bit(br->dead_node, dlm->live_nodes_map))
2743                         mlog(0, "%u not in domain/live_nodes map "
2744                              "so setting it in reco map manually\n",
2745                              br->dead_node);
2746                 /* force the recovery cleanup in __dlm_hb_node_down
2747                  * both of these will be cleared in a moment */
2748                 set_bit(br->dead_node, dlm->domain_map);
2749                 set_bit(br->dead_node, dlm->live_nodes_map);
2750                 __dlm_hb_node_down(dlm, br->dead_node);
2751         }
2752         spin_unlock(&dlm->spinlock);
2753
2754         dlm_kick_recovery_thread(dlm);
2755
2756         mlog(0, "%s: recovery started by node %u, for %u (%u:%u)\n",
2757              dlm->name, br->node_idx, br->dead_node,
2758              dlm->reco.dead_node, dlm->reco.new_master);
2759
2760         dlm_put(dlm);
2761         return 0;
2762 }
2763
2764 #define DLM_FINALIZE_STAGE2  0x01
2765 static int dlm_send_finalize_reco_message(struct dlm_ctxt *dlm)
2766 {
2767         int ret = 0;
2768         struct dlm_finalize_reco fr;
2769         struct dlm_node_iter iter;
2770         int nodenum;
2771         int status;
2772         int stage = 1;
2773
2774         mlog(0, "finishing recovery for node %s:%u, "
2775              "stage %d\n", dlm->name, dlm->reco.dead_node, stage);
2776
2777         spin_lock(&dlm->spinlock);
2778         dlm_node_iter_init(dlm->domain_map, &iter);
2779         spin_unlock(&dlm->spinlock);
2780
2781 stage2:
2782         memset(&fr, 0, sizeof(fr));
2783         fr.node_idx = dlm->node_num;
2784         fr.dead_node = dlm->reco.dead_node;
2785         if (stage == 2)
2786                 fr.flags |= DLM_FINALIZE_STAGE2;
2787
2788         while ((nodenum = dlm_node_iter_next(&iter)) >= 0) {
2789                 if (nodenum == dlm->node_num)
2790                         continue;
2791                 ret = o2net_send_message(DLM_FINALIZE_RECO_MSG, dlm->key,
2792                                          &fr, sizeof(fr), nodenum, &status);
2793                 if (ret >= 0)
2794                         ret = status;
2795                 if (ret < 0) {
2796                         mlog(ML_ERROR, "Error %d when sending message %u (key "
2797                              "0x%x) to node %u\n", ret, DLM_FINALIZE_RECO_MSG,
2798                              dlm->key, nodenum);
2799                         if (dlm_is_host_down(ret)) {
2800                                 /* this has no effect on this recovery
2801                                  * session, so set the status to zero to
2802                                  * finish out the last recovery */
2803                                 mlog(ML_ERROR, "node %u went down after this "
2804                                      "node finished recovery.\n", nodenum);
2805                                 ret = 0;
2806                                 continue;
2807                         }
2808                         break;
2809                 }
2810         }
2811         if (stage == 1) {
2812                 /* reset the node_iter back to the top and send finalize2 */
2813                 iter.curnode = -1;
2814                 stage = 2;
2815                 goto stage2;
2816         }
2817
2818         return ret;
2819 }
2820
2821 int dlm_finalize_reco_handler(struct o2net_msg *msg, u32 len, void *data,
2822                               void **ret_data)
2823 {
2824         struct dlm_ctxt *dlm = data;
2825         struct dlm_finalize_reco *fr = (struct dlm_finalize_reco *)msg->buf;
2826         int stage = 1;
2827
2828         /* ok to return 0, domain has gone away */
2829         if (!dlm_grab(dlm))
2830                 return 0;
2831
2832         if (fr->flags & DLM_FINALIZE_STAGE2)
2833                 stage = 2;
2834
2835         mlog(0, "%s: node %u finalizing recovery stage%d of "
2836              "node %u (%u:%u)\n", dlm->name, fr->node_idx, stage,
2837              fr->dead_node, dlm->reco.dead_node, dlm->reco.new_master);
2838
2839         spin_lock(&dlm->spinlock);
2840
2841         if (dlm->reco.new_master != fr->node_idx) {
2842                 mlog(ML_ERROR, "node %u sent recovery finalize msg, but node "
2843                      "%u is supposed to be the new master, dead=%u\n",
2844                      fr->node_idx, dlm->reco.new_master, fr->dead_node);
2845                 BUG();
2846         }
2847         if (dlm->reco.dead_node != fr->dead_node) {
2848                 mlog(ML_ERROR, "node %u sent recovery finalize msg for dead "
2849                      "node %u, but node %u is supposed to be dead\n",
2850                      fr->node_idx, fr->dead_node, dlm->reco.dead_node);
2851                 BUG();
2852         }
2853
2854         switch (stage) {
2855                 case 1:
2856                         dlm_finish_local_lockres_recovery(dlm, fr->dead_node, fr->node_idx);
2857                         if (dlm->reco.state & DLM_RECO_STATE_FINALIZE) {
2858                                 mlog(ML_ERROR, "%s: received finalize1 from "
2859                                      "new master %u for dead node %u, but "
2860                                      "this node has already received it!\n",
2861                                      dlm->name, fr->node_idx, fr->dead_node);
2862                                 dlm_print_reco_node_status(dlm);
2863                                 BUG();
2864                         }
2865                         dlm->reco.state |= DLM_RECO_STATE_FINALIZE;
2866                         spin_unlock(&dlm->spinlock);
2867                         break;
2868                 case 2:
2869                         if (!(dlm->reco.state & DLM_RECO_STATE_FINALIZE)) {
2870                                 mlog(ML_ERROR, "%s: received finalize2 from "
2871                                      "new master %u for dead node %u, but "
2872                                      "this node did not have finalize1!\n",
2873                                      dlm->name, fr->node_idx, fr->dead_node);
2874                                 dlm_print_reco_node_status(dlm);
2875                                 BUG();
2876                         }
2877                         dlm->reco.state &= ~DLM_RECO_STATE_FINALIZE;
2878                         spin_unlock(&dlm->spinlock);
2879                         dlm_reset_recovery(dlm);
2880                         dlm_kick_recovery_thread(dlm);
2881                         break;
2882                 default:
2883                         BUG();
2884         }
2885
2886         mlog(0, "%s: recovery done, reco master was %u, dead now %u, master now %u\n",
2887              dlm->name, fr->node_idx, dlm->reco.dead_node, dlm->reco.new_master);
2888
2889         dlm_put(dlm);
2890         return 0;
2891 }