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 void dlm_complete_recovery_thread(struct dlm_ctxt *dlm);
  59 int dlm_launch_recovery_thread(struct dlm_ctxt *dlm);
  60 void dlm_kick_recovery_thread(struct dlm_ctxt *dlm);
  61 static int dlm_do_recovery(struct dlm_ctxt *dlm);
  62
  63 static int dlm_pick_recovery_master(struct dlm_ctxt *dlm);
  64 static int dlm_remaster_locks(struct dlm_ctxt *dlm, u8 dead_node);
  65 static int dlm_init_recovery_area(struct dlm_ctxt *dlm, u8 dead_node);
  66 static int dlm_request_all_locks(struct dlm_ctxt *dlm,
  67                                  u8 request_from, u8 dead_node);
  68 static void dlm_destroy_recovery_area(struct dlm_ctxt *dlm, u8 dead_node);
  69
  70 static inline int dlm_num_locks_in_lockres(struct dlm_lock_resource *res);
  71 static void dlm_init_migratable_lockres(struct dlm_migratable_lockres *mres,
  72                                         const char *lockname, int namelen,
  73                                         int total_locks, u64 cookie,
  74                                         u8 flags, u8 master);
  75 static int dlm_send_mig_lockres_msg(struct dlm_ctxt *dlm,
  76                                     struct dlm_migratable_lockres *mres,
  77                                     u8 send_to,
  78                                     struct dlm_lock_resource *res,
  79                                     int total_locks);
  80 static int dlm_process_recovery_data(struct dlm_ctxt *dlm,
  81                                      struct dlm_lock_resource *res,
  82                                      struct dlm_migratable_lockres *mres);
  83 static int dlm_send_finalize_reco_message(struct dlm_ctxt *dlm);
  84 static int dlm_send_all_done_msg(struct dlm_ctxt *dlm,
  85                                  u8 dead_node, u8 send_to);
  86 static int dlm_send_begin_reco_message(struct dlm_ctxt *dlm, u8 dead_node);
  87 static void dlm_move_reco_locks_to_list(struct dlm_ctxt *dlm,
  88                                         struct list_head *list, u8 dead_node);
  89 static void dlm_finish_local_lockres_recovery(struct dlm_ctxt *dlm,
  90                                               u8 dead_node, u8 new_master);
  91 static void dlm_reco_ast(void *astdata);
  92 static void dlm_reco_bast(void *astdata, int blocked_type);
  93 static void dlm_reco_unlock_ast(void *astdata, enum dlm_status st);
  94 static void dlm_request_all_locks_worker(struct dlm_work_item *item,
  95                                          void *data);
  96 static void dlm_mig_lockres_worker(struct dlm_work_item *item, void *data);
  97 static int dlm_lockres_master_requery(struct dlm_ctxt *dlm,
  98                                       struct dlm_lock_resource *res,
  99                                       u8 *real_master);
 100
 101 static u64 dlm_get_next_mig_cookie(void);
 102
 103 static DEFINE_SPINLOCK(dlm_reco_state_lock);
 104 static DEFINE_SPINLOCK(dlm_mig_cookie_lock);
 105 static u64 dlm_mig_cookie = 1;
 106
 107 static u64 dlm_get_next_mig_cookie(void)
 108 {
 109         u64 c;
 110         spin_lock(&dlm_mig_cookie_lock);
 111         c = dlm_mig_cookie;
 112         if (dlm_mig_cookie == (~0ULL))
 113                 dlm_mig_cookie = 1;
 114         else
 115                 dlm_mig_cookie++;
 116         spin_unlock(&dlm_mig_cookie_lock);
 117         return c;
 118 }
 119
 120 static inline void dlm_set_reco_dead_node(struct dlm_ctxt *dlm,
 121                                           u8 dead_node)
 122 {
 123         assert_spin_locked(&dlm->spinlock);
 124         if (dlm->reco.dead_node != dead_node)
 125                 mlog(0, "%s: changing dead_node from %u to %u\n",
 126                      dlm->name, dlm->reco.dead_node, dead_node);
 127         dlm->reco.dead_node = dead_node;
 128 }
 129
 130 static inline void dlm_set_reco_master(struct dlm_ctxt *dlm,
 131                                        u8 master)
 132 {
 133         assert_spin_locked(&dlm->spinlock);
 134         mlog(0, "%s: changing new_master from %u to %u\n",
 135              dlm->name, dlm->reco.new_master, master);
 136         dlm->reco.new_master = master;
 137 }
 138
 139 static inline void __dlm_reset_recovery(struct dlm_ctxt *dlm)
 140 {
 141         assert_spin_locked(&dlm->spinlock);
 142         clear_bit(dlm->reco.dead_node, dlm->recovery_map);
 143         dlm_set_reco_dead_node(dlm, O2NM_INVALID_NODE_NUM);
 144         dlm_set_reco_master(dlm, O2NM_INVALID_NODE_NUM);
 145 }
 146
 147 static inline void dlm_reset_recovery(struct dlm_ctxt *dlm)
 148 {
 149         spin_lock(&dlm->spinlock);
 150         __dlm_reset_recovery(dlm);
 151         spin_unlock(&dlm->spinlock);
 152 }
 153
 154 /* Worker function used during recovery. */
 155 void dlm_dispatch_work(struct work_struct *work)
 156 {
 157         struct dlm_ctxt *dlm =
 158                 container_of(work, struct dlm_ctxt, dispatched_work);
 159         LIST_HEAD(tmp_list);
 160         struct dlm_work_item *item, *next;
 161         dlm_workfunc_t *workfunc;
 162         int tot=0;
 163
 164         spin_lock(&dlm->work_lock);
 165         list_splice_init(&dlm->work_list, &tmp_list);
 166         spin_unlock(&dlm->work_lock);
 167
 168         list_for_each_entry(item, &tmp_list, list) {
 169                 tot++;
 170         }
 171         mlog(0, "%s: work thread has %d work items\n", dlm->name, tot);
 172
 173         list_for_each_entry_safe(item, next, &tmp_list, list) {
 174                 workfunc = item->func;
 175                 list_del_init(&item->list);
 176
 177                 /* already have ref on dlm to avoid having
 178                  * it disappear.  just double-check. */
 179                 BUG_ON(item->dlm != dlm);
 180
 181                 /* this is allowed to sleep and
 182                  * call network stuff */
 183                 workfunc(item, item->data);
 184
 185                 dlm_put(dlm);
 186                 kfree(item);
 187         }
 188 }
 189
 190 /*
 191  * RECOVERY THREAD
 192  */
 193
 194 void dlm_kick_recovery_thread(struct dlm_ctxt *dlm)
 195 {
 196         /* wake the recovery thread
 197          * this will wake the reco thread in one of three places
 198          * 1) sleeping with no recovery happening
 199          * 2) sleeping with recovery mastered elsewhere
 200          * 3) recovery mastered here, waiting on reco data */
 201
 202         wake_up(&dlm->dlm_reco_thread_wq);
 203 }
 204
 205 /* Launch the recovery thread */
 206 int dlm_launch_recovery_thread(struct dlm_ctxt *dlm)
 207 {
 208         mlog(0, "starting dlm recovery thread...\n");
 209
 210         dlm->dlm_reco_thread_task = kthread_run(dlm_recovery_thread, dlm,
 211                                                 "dlm_reco_thread");
 212         if (IS_ERR(dlm->dlm_reco_thread_task)) {
 213                 mlog_errno(PTR_ERR(dlm->dlm_reco_thread_task));
 214                 dlm->dlm_reco_thread_task = NULL;
 215                 return -EINVAL;
 216         }
 217
 218         return 0;
 219 }
 220
 221 void dlm_complete_recovery_thread(struct dlm_ctxt *dlm)
 222 {
 223         if (dlm->dlm_reco_thread_task) {
 224                 mlog(0, "waiting for dlm recovery thread to exit\n");
 225                 kthread_stop(dlm->dlm_reco_thread_task);
 226                 dlm->dlm_reco_thread_task = NULL;
 227         }
 228 }
 229
 230
 231
 232 /*
 233  * this is lame, but here's how recovery works...
 234  * 1) all recovery threads cluster wide will work on recovering
 235  *    ONE node at a time
 236  * 2) negotiate who will take over all the locks for the dead node.
 237  *    thats right... ALL the locks.
 238  * 3) once a new master is chosen, everyone scans all locks
 239  *    and moves aside those mastered by the dead guy
 240  * 4) each of these locks should be locked until recovery is done
 241  * 5) the new master collects up all of secondary lock queue info
 242  *    one lock at a time, forcing each node to communicate back
 243  *    before continuing
 244  * 6) each secondary lock queue responds with the full known lock info
 245  * 7) once the new master has run all its locks, it sends a ALLDONE!
 246  *    message to everyone
 247  * 8) upon receiving this message, the secondary queue node unlocks
 248  *    and responds to the ALLDONE
 249  * 9) once the new master gets responses from everyone, he unlocks
 250  *    everything and recovery for this dead node is done
 251  *10) go back to 2) while there are still dead nodes
 252  *
 253  */
 254
 255 static void dlm_print_reco_node_status(struct dlm_ctxt *dlm)
 256 {
 257         struct dlm_reco_node_data *ndata;
 258         struct dlm_lock_resource *res;
 259
 260         mlog(ML_NOTICE, "%s(%d): recovery info, state=%s, dead=%u, master=%u\n",
 261              dlm->name, task_pid_nr(dlm->dlm_reco_thread_task),
 262              dlm->reco.state & DLM_RECO_STATE_ACTIVE ? "ACTIVE" : "inactive",
 263              dlm->reco.dead_node, dlm->reco.new_master);
 264
 265         list_for_each_entry(ndata, &dlm->reco.node_data, list) {
 266                 char *st = "unknown";
 267                 switch (ndata->state) {
 268                         case DLM_RECO_NODE_DATA_INIT:
 269                                 st = "init";
 270                                 break;
 271                         case DLM_RECO_NODE_DATA_REQUESTING:
 272                                 st = "requesting";
 273                                 break;
 274                         case DLM_RECO_NODE_DATA_DEAD:
 275                                 st = "dead";
 276                                 break;
 277                         case DLM_RECO_NODE_DATA_RECEIVING:
 278                                 st = "receiving";
 279                                 break;
 280                         case DLM_RECO_NODE_DATA_REQUESTED:
 281                                 st = "requested";
 282                                 break;
 283                         case DLM_RECO_NODE_DATA_DONE:
 284                                 st = "done";
 285                                 break;
 286                         case DLM_RECO_NODE_DATA_FINALIZE_SENT:
 287                                 st = "finalize-sent";
 288                                 break;
 289                         default:
 290                                 st = "bad";
 291                                 break;
 292                 }
 293                 mlog(ML_NOTICE, "%s: reco state, node %u, state=%s\n",
 294                      dlm->name, ndata->node_num, st);
 295         }
 296         list_for_each_entry(res, &dlm->reco.resources, recovering) {
 297                 mlog(ML_NOTICE, "%s: lockres %.*s on recovering list\n",
 298                      dlm->name, res->lockname.len, res->lockname.name);
 299         }
 300 }
 301
 302 #define DLM_RECO_THREAD_TIMEOUT_MS (5 * 1000)
 303
 304 static int dlm_recovery_thread(void *data)
 305 {
 306         int status;
 307         struct dlm_ctxt *dlm = data;
 308         unsigned long timeout = msecs_to_jiffies(DLM_RECO_THREAD_TIMEOUT_MS);
 309
 310         mlog(0, "dlm thread running for %s...\n", dlm->name);
 311
 312         while (!kthread_should_stop()) {
 313                 if (dlm_domain_fully_joined(dlm)) {
 314                         status = dlm_do_recovery(dlm);
 315                         if (status == -EAGAIN) {
 316                                 /* do not sleep, recheck immediately. */
 317                                 continue;
 318                         }
 319                         if (status < 0)
 320                                 mlog_errno(status);
 321                 }
 322
 323                 wait_event_interruptible_timeout(dlm->dlm_reco_thread_wq,
 324                                                  kthread_should_stop(),
 325                                                  timeout);
 326         }
 327
 328         mlog(0, "quitting DLM recovery thread\n");
 329         return 0;
 330 }
 331
 332 /* returns true when the recovery master has contacted us */
 333 static int dlm_reco_master_ready(struct dlm_ctxt *dlm)
 334 {
 335         int ready;
 336         spin_lock(&dlm->spinlock);
 337         ready = (dlm->reco.new_master != O2NM_INVALID_NODE_NUM);
 338         spin_unlock(&dlm->spinlock);
 339         return ready;
 340 }
 341
 342 /* returns true if node is no longer in the domain
 343  * could be dead or just not joined */
 344 int dlm_is_node_dead(struct dlm_ctxt *dlm, u8 node)
 345 {
 346         int dead;
 347         spin_lock(&dlm->spinlock);
 348         dead = !test_bit(node, dlm->domain_map);
 349         spin_unlock(&dlm->spinlock);
 350         return dead;
 351 }
 352
 353 /* returns true if node is no longer in the domain
 354  * could be dead or just not joined */
 355 static int dlm_is_node_recovered(struct dlm_ctxt *dlm, u8 node)
 356 {
 357         int recovered;
 358         spin_lock(&dlm->spinlock);
 359         recovered = !test_bit(node, dlm->recovery_map);
 360         spin_unlock(&dlm->spinlock);
 361         return recovered;
 362 }
 363
 364
 365 int dlm_wait_for_node_death(struct dlm_ctxt *dlm, u8 node, int timeout)
 366 {
 367         if (timeout) {
 368                 mlog(ML_NOTICE, "%s: waiting %dms for notification of "
 369                      "death of node %u\n", dlm->name, timeout, node);
 370                 wait_event_timeout(dlm->dlm_reco_thread_wq,
 371                            dlm_is_node_dead(dlm, node),
 372                            msecs_to_jiffies(timeout));
 373         } else {
 374                 mlog(ML_NOTICE, "%s: waiting indefinitely for notification "
 375                      "of death of node %u\n", dlm->name, node);
 376                 wait_event(dlm->dlm_reco_thread_wq,
 377                            dlm_is_node_dead(dlm, node));
 378         }
 379         /* for now, return 0 */
 380         return 0;
 381 }
 382
 383 int dlm_wait_for_node_recovery(struct dlm_ctxt *dlm, u8 node, int timeout)
 384 {
 385         if (timeout) {
 386                 mlog(0, "%s: waiting %dms for notification of "
 387                      "recovery of node %u\n", dlm->name, timeout, node);
 388                 wait_event_timeout(dlm->dlm_reco_thread_wq,
 389                            dlm_is_node_recovered(dlm, node),
 390                            msecs_to_jiffies(timeout));
 391         } else {
 392                 mlog(0, "%s: waiting indefinitely for notification "
 393                      "of recovery of node %u\n", dlm->name, node);
 394                 wait_event(dlm->dlm_reco_thread_wq,
 395                            dlm_is_node_recovered(dlm, node));
 396         }
 397         /* for now, return 0 */
 398         return 0;
 399 }
 400
 401 /* callers of the top-level api calls (dlmlock/dlmunlock) should
 402  * block on the dlm->reco.event when recovery is in progress.
 403  * the dlm recovery thread will set this state when it begins
 404  * recovering a dead node (as the new master or not) and clear
 405  * the state and wake as soon as all affected lock resources have
 406  * been marked with the RECOVERY flag */
 407 static int dlm_in_recovery(struct dlm_ctxt *dlm)
 408 {
 409         int in_recovery;
 410         spin_lock(&dlm->spinlock);
 411         in_recovery = !!(dlm->reco.state & DLM_RECO_STATE_ACTIVE);
 412         spin_unlock(&dlm->spinlock);
 413         return in_recovery;
 414 }
 415
 416
 417 void dlm_wait_for_recovery(struct dlm_ctxt *dlm)
 418 {
 419         if (dlm_in_recovery(dlm)) {
 420                 mlog(0, "%s: reco thread %d in recovery: "
 421                      "state=%d, master=%u, dead=%u\n",
 422                      dlm->name, task_pid_nr(dlm->dlm_reco_thread_task),
 423                      dlm->reco.state, dlm->reco.new_master,
 424                      dlm->reco.dead_node);
 425         }
 426         wait_event(dlm->reco.event, !dlm_in_recovery(dlm));
 427 }
 428
 429 static void dlm_begin_recovery(struct dlm_ctxt *dlm)
 430 {
 431         spin_lock(&dlm->spinlock);
 432         BUG_ON(dlm->reco.state & DLM_RECO_STATE_ACTIVE);
 433         dlm->reco.state |= DLM_RECO_STATE_ACTIVE;
 434         spin_unlock(&dlm->spinlock);
 435 }
 436
 437 static void dlm_end_recovery(struct dlm_ctxt *dlm)
 438 {
 439         spin_lock(&dlm->spinlock);
 440         BUG_ON(!(dlm->reco.state & DLM_RECO_STATE_ACTIVE));
 441         dlm->reco.state &= ~DLM_RECO_STATE_ACTIVE;
 442         spin_unlock(&dlm->spinlock);
 443         wake_up(&dlm->reco.event);
 444 }
 445
 446 static int dlm_do_recovery(struct dlm_ctxt *dlm)
 447 {
 448         int status = 0;
 449         int ret;
 450
 451         spin_lock(&dlm->spinlock);
 452
 453         /* check to see if the new master has died */
 454         if (dlm->reco.new_master != O2NM_INVALID_NODE_NUM &&
 455             test_bit(dlm->reco.new_master, dlm->recovery_map)) {
 456                 mlog(0, "new master %u died while recovering %u!\n",
 457                      dlm->reco.new_master, dlm->reco.dead_node);
 458                 /* unset the new_master, leave dead_node */
 459                 dlm_set_reco_master(dlm, O2NM_INVALID_NODE_NUM);
 460         }
 461
 462         /* select a target to recover */
 463         if (dlm->reco.dead_node == O2NM_INVALID_NODE_NUM) {
 464                 int bit;
 465
 466                 bit = find_next_bit (dlm->recovery_map, O2NM_MAX_NODES, 0);
 467                 if (bit >= O2NM_MAX_NODES || bit < 0)
 468                         dlm_set_reco_dead_node(dlm, O2NM_INVALID_NODE_NUM);
 469                 else
 470                         dlm_set_reco_dead_node(dlm, bit);
 471         } else if (!test_bit(dlm->reco.dead_node, dlm->recovery_map)) {
 472                 /* BUG? */
 473                 mlog(ML_ERROR, "dead_node %u no longer in recovery map!\n",
 474                      dlm->reco.dead_node);
 475                 dlm_set_reco_dead_node(dlm, O2NM_INVALID_NODE_NUM);
 476         }
 477
 478         if (dlm->reco.dead_node == O2NM_INVALID_NODE_NUM) {
 479                 // mlog(0, "nothing to recover!  sleeping now!\n");
 480                 spin_unlock(&dlm->spinlock);
 481                 /* return to main thread loop and sleep. */
 482                 return 0;
 483         }
 484         mlog(0, "%s(%d):recovery thread found node %u in the recovery map!\n",
 485              dlm->name, task_pid_nr(dlm->dlm_reco_thread_task),
 486              dlm->reco.dead_node);
 487         spin_unlock(&dlm->spinlock);
 488
 489         /* take write barrier */
 490         /* (stops the list reshuffling thread, proxy ast handling) */
 491         dlm_begin_recovery(dlm);
 492
 493         if (dlm->reco.new_master == dlm->node_num)
 494                 goto master_here;
 495
 496         if (dlm->reco.new_master == O2NM_INVALID_NODE_NUM) {
 497                 /* choose a new master, returns 0 if this node
 498                  * is the master, -EEXIST if it's another node.
 499                  * this does not return until a new master is chosen
 500                  * or recovery completes entirely. */
 501                 ret = dlm_pick_recovery_master(dlm);
 502                 if (!ret) {
 503                         /* already notified everyone.  go. */
 504                         goto master_here;
 505                 }
 506                 mlog(0, "another node will master this recovery session.\n");
 507         }
 508         mlog(0, "dlm=%s (%d), new_master=%u, this node=%u, dead_node=%u\n",
 509              dlm->name, task_pid_nr(dlm->dlm_reco_thread_task), dlm->reco.new_master,
 510              dlm->node_num, dlm->reco.dead_node);
 511
 512         /* it is safe to start everything back up here
 513          * because all of the dead node's lock resources
 514          * have been marked as in-recovery */
 515         dlm_end_recovery(dlm);
 516
 517         /* sleep out in main dlm_recovery_thread loop. */
 518         return 0;
 519
 520 master_here:
 521         mlog(ML_NOTICE, "(%d) Node %u is the Recovery Master for the Dead Node "
 522              "%u for Domain %s\n", task_pid_nr(dlm->dlm_reco_thread_task),
 523              dlm->node_num, dlm->reco.dead_node, dlm->name);
 524
 525         status = dlm_remaster_locks(dlm, dlm->reco.dead_node);
 526         if (status < 0) {
 527                 /* we should never hit this anymore */
 528                 mlog(ML_ERROR, "error %d remastering locks for node %u, "
 529                      "retrying.\n", status, dlm->reco.dead_node);
 530                 /* yield a bit to allow any final network messages
 531                  * to get handled on remaining nodes */
 532                 msleep(100);
 533         } else {
 534                 /* success!  see if any other nodes need recovery */
 535                 mlog(0, "DONE mastering recovery of %s:%u here(this=%u)!\n",
 536                      dlm->name, dlm->reco.dead_node, dlm->node_num);
 537                 dlm_reset_recovery(dlm);
 538         }
 539         dlm_end_recovery(dlm);
 540
 541         /* continue and look for another dead node */
 542         return -EAGAIN;
 543 }
 544
 545 static int dlm_remaster_locks(struct dlm_ctxt *dlm, u8 dead_node)
 546 {
 547         int status = 0;
 548         struct dlm_reco_node_data *ndata;
 549         int all_nodes_done;
 550         int destroy = 0;
 551         int pass = 0;
 552
 553         do {
 554                 /* we have become recovery master.  there is no escaping
 555                  * this, so just keep trying until we get it. */
 556                 status = dlm_init_recovery_area(dlm, dead_node);
 557                 if (status < 0) {
 558                         mlog(ML_ERROR, "%s: failed to alloc recovery area, "
 559                              "retrying\n", dlm->name);
 560                         msleep(1000);
 561                 }
 562         } while (status != 0);
 563
 564         /* safe to access the node data list without a lock, since this
 565          * process is the only one to change the list */
 566         list_for_each_entry(ndata, &dlm->reco.node_data, list) {
 567                 BUG_ON(ndata->state != DLM_RECO_NODE_DATA_INIT);
 568                 ndata->state = DLM_RECO_NODE_DATA_REQUESTING;
 569
 570                 mlog(0, "requesting lock info from node %u\n",
 571                      ndata->node_num);
 572
 573                 if (ndata->node_num == dlm->node_num) {
 574                         ndata->state = DLM_RECO_NODE_DATA_DONE;
 575                         continue;
 576                 }
 577
 578                 do {
 579                         status = dlm_request_all_locks(dlm, ndata->node_num,
 580                                                        dead_node);
 581                         if (status < 0) {
 582                                 mlog_errno(status);
 583                                 if (dlm_is_host_down(status)) {
 584                                         /* node died, ignore it for recovery */
 585                                         status = 0;
 586                                         ndata->state = DLM_RECO_NODE_DATA_DEAD;
 587                                         /* wait for the domain map to catch up
 588                                          * with the network state. */
 589                                         wait_event_timeout(dlm->dlm_reco_thread_wq,
 590                                                            dlm_is_node_dead(dlm,
 591                                                                 ndata->node_num),
 592                                                            msecs_to_jiffies(1000));
 593                                         mlog(0, "waited 1 sec for %u, "
 594                                              "dead? %s\n", ndata->node_num,
 595                                              dlm_is_node_dead(dlm, ndata->node_num) ?
 596                                              "yes" : "no");
 597                                 } else {
 598                                         /* -ENOMEM on the other node */
 599                                         mlog(0, "%s: node %u returned "
 600                                              "%d during recovery, retrying "
 601                                              "after a short wait\n",
 602                                              dlm->name, ndata->node_num,
 603                                              status);
 604                                         msleep(100);
 605                                 }
 606                         }
 607                 } while (status != 0);
 608
 609                 spin_lock(&dlm_reco_state_lock);
 610                 switch (ndata->state) {
 611                         case DLM_RECO_NODE_DATA_INIT:
 612                         case DLM_RECO_NODE_DATA_FINALIZE_SENT:
 613                         case DLM_RECO_NODE_DATA_REQUESTED:
 614                                 BUG();
 615                                 break;
 616                         case DLM_RECO_NODE_DATA_DEAD:
 617                                 mlog(0, "node %u died after requesting "
 618                                      "recovery info for node %u\n",
 619                                      ndata->node_num, dead_node);
 620                                 /* fine.  don't need this node's info.
 621                                  * continue without it. */
 622                                 break;
 623                         case DLM_RECO_NODE_DATA_REQUESTING:
 624                                 ndata->state = DLM_RECO_NODE_DATA_REQUESTED;
 625                                 mlog(0, "now receiving recovery data from "
 626                                      "node %u for dead node %u\n",
 627                                      ndata->node_num, dead_node);
 628                                 break;
 629                         case DLM_RECO_NODE_DATA_RECEIVING:
 630                                 mlog(0, "already receiving recovery data from "
 631                                      "node %u for dead node %u\n",
 632                                      ndata->node_num, dead_node);
 633                                 break;
 634                         case DLM_RECO_NODE_DATA_DONE:
 635                                 mlog(0, "already DONE receiving recovery data "
 636                                      "from node %u for dead node %u\n",
 637                                      ndata->node_num, dead_node);
 638                                 break;
 639                 }
 640                 spin_unlock(&dlm_reco_state_lock);
 641         }
 642
 643         mlog(0, "done requesting all lock info\n");
 644
 645         /* nodes should be sending reco data now
 646          * just need to wait */
 647
 648         while (1) {
 649                 /* check all the nodes now to see if we are
 650                  * done, or if anyone died */
 651                 all_nodes_done = 1;
 652                 spin_lock(&dlm_reco_state_lock);
 653                 list_for_each_entry(ndata, &dlm->reco.node_data, list) {
 654                         mlog(0, "checking recovery state of node %u\n",
 655                              ndata->node_num);
 656                         switch (ndata->state) {
 657                                 case DLM_RECO_NODE_DATA_INIT:
 658                                 case DLM_RECO_NODE_DATA_REQUESTING:
 659                                         mlog(ML_ERROR, "bad ndata state for "
 660                                              "node %u: state=%d\n",
 661                                              ndata->node_num, ndata->state);
 662                                         BUG();
 663                                         break;
 664                                 case DLM_RECO_NODE_DATA_DEAD:
 665                                         mlog(0, "node %u died after "
 666                                              "requesting recovery info for "
 667                                              "node %u\n", ndata->node_num,
 668                                              dead_node);
 669                                         break;
 670                                 case DLM_RECO_NODE_DATA_RECEIVING:
 671                                 case DLM_RECO_NODE_DATA_REQUESTED:
 672                                         mlog(0, "%s: node %u still in state %s\n",
 673                                              dlm->name, ndata->node_num,
 674                                              ndata->state==DLM_RECO_NODE_DATA_RECEIVING ?
 675                                              "receiving" : "requested");
 676                                         all_nodes_done = 0;
 677                                         break;
 678                                 case DLM_RECO_NODE_DATA_DONE:
 679                                         mlog(0, "%s: node %u state is done\n",
 680                                              dlm->name, ndata->node_num);
 681                                         break;
 682                                 case DLM_RECO_NODE_DATA_FINALIZE_SENT:
 683                                         mlog(0, "%s: node %u state is finalize\n",
 684                                              dlm->name, ndata->node_num);
 685                                         break;
 686                         }
 687                 }
 688                 spin_unlock(&dlm_reco_state_lock);
 689
 690                 mlog(0, "pass #%d, all_nodes_done?: %s\n", ++pass,
 691                      all_nodes_done?"yes":"no");
 692                 if (all_nodes_done) {
 693                         int ret;
 694
 695                         /* all nodes are now in DLM_RECO_NODE_DATA_DONE state
 696                          * just send a finalize message to everyone and
 697                          * clean up */
 698                         mlog(0, "all nodes are done! send finalize\n");
 699                         ret = dlm_send_finalize_reco_message(dlm);
 700                         if (ret < 0)
 701                                 mlog_errno(ret);
 702
 703                         spin_lock(&dlm->spinlock);
 704                         dlm_finish_local_lockres_recovery(dlm, dead_node,
 705                                                           dlm->node_num);
 706                         spin_unlock(&dlm->spinlock);
 707                         mlog(0, "should be done with recovery!\n");
 708
 709                         mlog(0, "finishing recovery of %s at %lu, "
 710                              "dead=%u, this=%u, new=%u\n", dlm->name,
 711                              jiffies, dlm->reco.dead_node,
 712                              dlm->node_num, dlm->reco.new_master);
 713                         destroy = 1;
 714                         status = 0;
 715                         /* rescan everything marked dirty along the way */
 716                         dlm_kick_thread(dlm, NULL);
 717                         break;
 718                 }
 719                 /* wait to be signalled, with periodic timeout
 720                  * to check for node death */
 721                 wait_event_interruptible_timeout(dlm->dlm_reco_thread_wq,
 722                                          kthread_should_stop(),
 723                                          msecs_to_jiffies(DLM_RECO_THREAD_TIMEOUT_MS));
 724
 725         }
 726
 727         if (destroy)
 728                 dlm_destroy_recovery_area(dlm, dead_node);
 729
 730         mlog_exit(status);
 731         return status;
 732 }
 733
 734 static int dlm_init_recovery_area(struct dlm_ctxt *dlm, u8 dead_node)
 735 {
 736         int num=0;
 737         struct dlm_reco_node_data *ndata;
 738
 739         spin_lock(&dlm->spinlock);
 740         memcpy(dlm->reco.node_map, dlm->domain_map, sizeof(dlm->domain_map));
 741         /* nodes can only be removed (by dying) after dropping
 742          * this lock, and death will be trapped later, so this should do */
 743         spin_unlock(&dlm->spinlock);
 744
 745         while (1) {
 746                 num = find_next_bit (dlm->reco.node_map, O2NM_MAX_NODES, num);
 747                 if (num >= O2NM_MAX_NODES) {
 748                         break;
 749                 }
 750                 BUG_ON(num == dead_node);
 751
 752                 ndata = kzalloc(sizeof(*ndata), GFP_NOFS);
 753                 if (!ndata) {
 754                         dlm_destroy_recovery_area(dlm, dead_node);
 755                         return -ENOMEM;
 756                 }
 757                 ndata->node_num = num;
 758                 ndata->state = DLM_RECO_NODE_DATA_INIT;
 759                 spin_lock(&dlm_reco_state_lock);
 760                 list_add_tail(&ndata->list, &dlm->reco.node_data);
 761                 spin_unlock(&dlm_reco_state_lock);
 762                 num++;
 763         }
 764
 765         return 0;
 766 }
 767
 768 static void dlm_destroy_recovery_area(struct dlm_ctxt *dlm, u8 dead_node)
 769 {
 770         struct dlm_reco_node_data *ndata, *next;
 771         LIST_HEAD(tmplist);
 772
 773         spin_lock(&dlm_reco_state_lock);
 774         list_splice_init(&dlm->reco.node_data, &tmplist);
 775         spin_unlock(&dlm_reco_state_lock);
 776
 777         list_for_each_entry_safe(ndata, next, &tmplist, list) {
 778                 list_del_init(&ndata->list);
 779                 kfree(ndata);
 780         }
 781 }
 782
 783 static int dlm_request_all_locks(struct dlm_ctxt *dlm, u8 request_from,
 784                                  u8 dead_node)
 785 {
 786         struct dlm_lock_request lr;
 787         enum dlm_status ret;
 788
 789         mlog(0, "\n");
 790
 791
 792         mlog(0, "dlm_request_all_locks: dead node is %u, sending request "
 793                   "to %u\n", dead_node, request_from);
 794
 795         memset(&lr, 0, sizeof(lr));
 796         lr.node_idx = dlm->node_num;
 797         lr.dead_node = dead_node;
 798
 799         // send message
 800         ret = DLM_NOLOCKMGR;
 801         ret = o2net_send_message(DLM_LOCK_REQUEST_MSG, dlm->key,
 802                                  &lr, sizeof(lr), request_from, NULL);
 803
 804         /* negative status is handled by caller */
 805         if (ret < 0)
 806                 mlog(ML_ERROR, "Error %d when sending message %u (key "
 807                      "0x%x) to node %u\n", ret, DLM_LOCK_REQUEST_MSG,
 808                      dlm->key, request_from);
 809
 810         // return from here, then
 811         // sleep until all received or error
 812         return ret;
 813
 814 }
 815
 816 int dlm_request_all_locks_handler(struct o2net_msg *msg, u32 len, void *data,
 817                                   void **ret_data)
 818 {
 819         struct dlm_ctxt *dlm = data;
 820         struct dlm_lock_request *lr = (struct dlm_lock_request *)msg->buf;
 821         char *buf = NULL;
 822         struct dlm_work_item *item = NULL;
 823
 824         if (!dlm_grab(dlm))
 825                 return -EINVAL;
 826
 827         if (lr->dead_node != dlm->reco.dead_node) {
 828                 mlog(ML_ERROR, "%s: node %u sent dead_node=%u, but local "
 829                      "dead_node is %u\n", dlm->name, lr->node_idx,
 830                      lr->dead_node, dlm->reco.dead_node);
 831                 dlm_print_reco_node_status(dlm);
 832                 /* this is a hack */
 833                 dlm_put(dlm);
 834                 return -ENOMEM;
 835         }
 836         BUG_ON(lr->dead_node != dlm->reco.dead_node);
 837
 838         item = kzalloc(sizeof(*item), GFP_NOFS);
 839         if (!item) {
 840                 dlm_put(dlm);
 841                 return -ENOMEM;
 842         }
 843
 844         /* this will get freed by dlm_request_all_locks_worker */
 845         buf = (char *) __get_free_page(GFP_NOFS);
 846         if (!buf) {
 847                 kfree(item);
 848                 dlm_put(dlm);
 849                 return -ENOMEM;
 850         }
 851
 852         /* queue up work for dlm_request_all_locks_worker */
 853         dlm_grab(dlm);  /* get an extra ref for the work item */
 854         dlm_init_work_item(dlm, item, dlm_request_all_locks_worker, buf);
 855         item->u.ral.reco_master = lr->node_idx;
 856         item->u.ral.dead_node = lr->dead_node;
 857         spin_lock(&dlm->work_lock);
 858         list_add_tail(&item->list, &dlm->work_list);
 859         spin_unlock(&dlm->work_lock);
 860         queue_work(dlm->dlm_worker, &dlm->dispatched_work);
 861
 862         dlm_put(dlm);
 863         return 0;
 864 }
 865
 866 static void dlm_request_all_locks_worker(struct dlm_work_item *item, void *data)
 867 {
 868         struct dlm_migratable_lockres *mres;
 869         struct dlm_lock_resource *res;
 870         struct dlm_ctxt *dlm;
 871         LIST_HEAD(resources);
 872         int ret;
 873         u8 dead_node, reco_master;
 874         int skip_all_done = 0;
 875
 876         dlm = item->dlm;
 877         dead_node = item->u.ral.dead_node;
 878         reco_master = item->u.ral.reco_master;
 879         mres = (struct dlm_migratable_lockres *)data;
 880
 881         mlog(0, "%s: recovery worker started, dead=%u, master=%u\n",
 882              dlm->name, dead_node, reco_master);
 883
 884         if (dead_node != dlm->reco.dead_node ||
 885             reco_master != dlm->reco.new_master) {
 886                 /* worker could have been created before the recovery master
 887                  * died.  if so, do not continue, but do not error. */
 888                 if (dlm->reco.new_master == O2NM_INVALID_NODE_NUM) {
 889                         mlog(ML_NOTICE, "%s: will not send recovery state, "
 890                              "recovery master %u died, thread=(dead=%u,mas=%u)"
 891                              " current=(dead=%u,mas=%u)\n", dlm->name,
 892                              reco_master, dead_node, reco_master,
 893                              dlm->reco.dead_node, dlm->reco.new_master);
 894                 } else {
 895                         mlog(ML_NOTICE, "%s: reco state invalid: reco(dead=%u, "
 896                              "master=%u), request(dead=%u, master=%u)\n",
 897                              dlm->name, dlm->reco.dead_node,
 898                              dlm->reco.new_master, dead_node, reco_master);
 899                 }
 900                 goto leave;
 901         }
 902
 903         /* lock resources should have already been moved to the
 904          * dlm->reco.resources list.  now move items from that list
 905          * to a temp list if the dead owner matches.  note that the
 906          * whole cluster recovers only one node at a time, so we
 907          * can safely move UNKNOWN lock resources for each recovery
 908          * session. */
 909         dlm_move_reco_locks_to_list(dlm, &resources, dead_node);
 910
 911         /* now we can begin blasting lockreses without the dlm lock */
 912
 913         /* any errors returned will be due to the new_master dying,
 914          * the dlm_reco_thread should detect this */
 915         list_for_each_entry(res, &resources, recovering) {
 916                 ret = dlm_send_one_lockres(dlm, res, mres, reco_master,
 917                                         DLM_MRES_RECOVERY);
 918                 if (ret < 0) {
 919                         mlog(ML_ERROR, "%s: node %u went down while sending "
 920                              "recovery state for dead node %u, ret=%d\n", dlm->name,
 921                              reco_master, dead_node, ret);
 922                         skip_all_done = 1;
 923                         break;
 924                 }
 925         }
 926
 927         /* move the resources back to the list */
 928         spin_lock(&dlm->spinlock);
 929         list_splice_init(&resources, &dlm->reco.resources);
 930         spin_unlock(&dlm->spinlock);
 931
 932         if (!skip_all_done) {
 933                 ret = dlm_send_all_done_msg(dlm, dead_node, reco_master);
 934                 if (ret < 0) {
 935                         mlog(ML_ERROR, "%s: node %u went down while sending "
 936                              "recovery all-done for dead node %u, ret=%d\n",
 937                              dlm->name, reco_master, dead_node, ret);
 938                 }
 939         }
 940 leave:
 941         free_page((unsigned long)data);
 942 }
 943
 944
 945 static int dlm_send_all_done_msg(struct dlm_ctxt *dlm, u8 dead_node, u8 send_to)
 946 {
 947         int ret, tmpret;
 948         struct dlm_reco_data_done done_msg;
 949
 950         memset(&done_msg, 0, sizeof(done_msg));
 951         done_msg.node_idx = dlm->node_num;
 952         done_msg.dead_node = dead_node;
 953         mlog(0, "sending DATA DONE message to %u, "
 954              "my node=%u, dead node=%u\n", send_to, done_msg.node_idx,
 955              done_msg.dead_node);
 956
 957         ret = o2net_send_message(DLM_RECO_DATA_DONE_MSG, dlm->key, &done_msg,
 958                                  sizeof(done_msg), send_to, &tmpret);
 959         if (ret < 0) {
 960                 mlog(ML_ERROR, "Error %d when sending message %u (key "
 961                      "0x%x) to node %u\n", ret, DLM_RECO_DATA_DONE_MSG,
 962                      dlm->key, send_to);
 963                 if (!dlm_is_host_down(ret)) {
 964                         BUG();
 965                 }
 966         } else
 967                 ret = tmpret;
 968         return ret;
 969 }
 970
 971
 972 int dlm_reco_data_done_handler(struct o2net_msg *msg, u32 len, void *data,
 973                                void **ret_data)
 974 {
 975         struct dlm_ctxt *dlm = data;
 976         struct dlm_reco_data_done *done = (struct dlm_reco_data_done *)msg->buf;
 977         struct dlm_reco_node_data *ndata = NULL;
 978         int ret = -EINVAL;
 979
 980         if (!dlm_grab(dlm))
 981                 return -EINVAL;
 982
 983         mlog(0, "got DATA DONE: dead_node=%u, reco.dead_node=%u, "
 984              "node_idx=%u, this node=%u\n", done->dead_node,
 985              dlm->reco.dead_node, done->node_idx, dlm->node_num);
 986
 987         mlog_bug_on_msg((done->dead_node != dlm->reco.dead_node),
 988                         "Got DATA DONE: dead_node=%u, reco.dead_node=%u, "
 989                         "node_idx=%u, this node=%u\n", done->dead_node,
 990                         dlm->reco.dead_node, done->node_idx, dlm->node_num);
 991
 992         spin_lock(&dlm_reco_state_lock);
 993         list_for_each_entry(ndata, &dlm->reco.node_data, list) {
 994                 if (ndata->node_num != done->node_idx)
 995                         continue;
 996
 997                 switch (ndata->state) {
 998                         /* should have moved beyond INIT but not to FINALIZE yet */
 999                         case DLM_RECO_NODE_DATA_INIT:
1000                         case DLM_RECO_NODE_DATA_DEAD:
1001                         case DLM_RECO_NODE_DATA_FINALIZE_SENT:
1002                                 mlog(ML_ERROR, "bad ndata state for node %u:"
1003                                      " state=%d\n", ndata->node_num,
1004                                      ndata->state);
1005                                 BUG();
1006                                 break;
1007                         /* these states are possible at this point, anywhere along
1008                          * the line of recovery */
1009                         case DLM_RECO_NODE_DATA_DONE:
1010                         case DLM_RECO_NODE_DATA_RECEIVING:
1011                         case DLM_RECO_NODE_DATA_REQUESTED:
1012                         case DLM_RECO_NODE_DATA_REQUESTING:
1013                                 mlog(0, "node %u is DONE sending "
1014                                           "recovery data!\n",
1015                                           ndata->node_num);
1016
1017                                 ndata->state = DLM_RECO_NODE_DATA_DONE;
1018                                 ret = 0;
1019                                 break;
1020                 }
1021         }
1022         spin_unlock(&dlm_reco_state_lock);
1023
1024         /* wake the recovery thread, some node is done */
1025         if (!ret)
1026                 dlm_kick_recovery_thread(dlm);
1027
1028         if (ret < 0)
1029                 mlog(ML_ERROR, "failed to find recovery node data for node "
1030                      "%u\n", done->node_idx);
1031         dlm_put(dlm);
1032
1033         mlog(0, "leaving reco data done handler, ret=%d\n", ret);
1034         return ret;
1035 }
1036
1037 static void dlm_move_reco_locks_to_list(struct dlm_ctxt *dlm,
1038                                         struct list_head *list,
1039                                         u8 dead_node)
1040 {
1041         struct dlm_lock_resource *res, *next;
1042         struct dlm_lock *lock;
1043
1044         spin_lock(&dlm->spinlock);
1045         list_for_each_entry_safe(res, next, &dlm->reco.resources, recovering) {
1046                 /* always prune any $RECOVERY entries for dead nodes,
1047                  * otherwise hangs can occur during later recovery */
1048                 if (dlm_is_recovery_lock(res->lockname.name,
1049                                          res->lockname.len)) {
1050                         spin_lock(&res->spinlock);
1051                         list_for_each_entry(lock, &res->granted, list) {
1052                                 if (lock->ml.node == dead_node) {
1053                                         mlog(0, "AHA! there was "
1054                                              "a $RECOVERY lock for dead "
1055                                              "node %u (%s)!\n",
1056                                              dead_node, dlm->name);
1057                                         list_del_init(&lock->list);
1058                                         dlm_lock_put(lock);
1059                                         break;
1060                                 }
1061                         }
1062                         spin_unlock(&res->spinlock);
1063                         continue;
1064                 }
1065
1066                 if (res->owner == dead_node) {
1067                         mlog(0, "found lockres owned by dead node while "
1068                                   "doing recovery for node %u. sending it.\n",
1069                                   dead_node);
1070                         list_move_tail(&res->recovering, list);
1071                 } else if (res->owner == DLM_LOCK_RES_OWNER_UNKNOWN) {
1072                         mlog(0, "found UNKNOWN owner while doing recovery "
1073                                   "for node %u. sending it.\n", dead_node);
1074                         list_move_tail(&res->recovering, list);
1075                 }
1076         }
1077         spin_unlock(&dlm->spinlock);
1078 }
1079
1080 static inline int dlm_num_locks_in_lockres(struct dlm_lock_resource *res)
1081 {
1082         int total_locks = 0;
1083         struct list_head *iter, *queue = &res->granted;
1084         int i;
1085
1086         for (i=0; i<3; i++) {
1087                 list_for_each(iter, queue)
1088                         total_locks++;
1089                 queue++;
1090         }
1091         return total_locks;
1092 }
1093
1094
1095 static int dlm_send_mig_lockres_msg(struct dlm_ctxt *dlm,
1096                                       struct dlm_migratable_lockres *mres,
1097                                       u8 send_to,
1098                                       struct dlm_lock_resource *res,
1099                                       int total_locks)
1100 {
1101         u64 mig_cookie = be64_to_cpu(mres->mig_cookie);
1102         int mres_total_locks = be32_to_cpu(mres->total_locks);
1103         int sz, ret = 0, status = 0;
1104         u8 orig_flags = mres->flags,
1105            orig_master = mres->master;
1106
1107         BUG_ON(mres->num_locks > DLM_MAX_MIGRATABLE_LOCKS);
1108         if (!mres->num_locks)
1109                 return 0;
1110
1111         sz = sizeof(struct dlm_migratable_lockres) +
1112                 (mres->num_locks * sizeof(struct dlm_migratable_lock));
1113
1114         /* add an all-done flag if we reached the last lock */
1115         orig_flags = mres->flags;
1116         BUG_ON(total_locks > mres_total_locks);
1117         if (total_locks == mres_total_locks)
1118                 mres->flags |= DLM_MRES_ALL_DONE;
1119
1120         mlog(0, "%s:%.*s: sending mig lockres (%s) to %u\n",
1121              dlm->name, res->lockname.len, res->lockname.name,
1122              orig_flags & DLM_MRES_MIGRATION ? "migration" : "recovery",
1123              send_to);
1124
1125         /* send it */
1126         ret = o2net_send_message(DLM_MIG_LOCKRES_MSG, dlm->key, mres,
1127                                  sz, send_to, &status);
1128         if (ret < 0) {
1129                 /* XXX: negative status is not handled.
1130                  * this will end up killing this node. */
1131                 mlog(ML_ERROR, "Error %d when sending message %u (key "
1132                      "0x%x) to node %u\n", ret, DLM_MIG_LOCKRES_MSG,
1133                      dlm->key, send_to);
1134         } else {
1135                 /* might get an -ENOMEM back here */
1136                 ret = status;
1137                 if (ret < 0) {
1138                         mlog_errno(ret);
1139
1140                         if (ret == -EFAULT) {
1141                                 mlog(ML_ERROR, "node %u told me to kill "
1142                                      "myself!\n", send_to);
1143                                 BUG();
1144                         }
1145                 }
1146         }
1147
1148         /* zero and reinit the message buffer */
1149         dlm_init_migratable_lockres(mres, res->lockname.name,
1150                                     res->lockname.len, mres_total_locks,
1151                                     mig_cookie, orig_flags, orig_master);
1152         return ret;
1153 }
1154
1155 static void dlm_init_migratable_lockres(struct dlm_migratable_lockres *mres,
1156                                         const char *lockname, int namelen,
1157                                         int total_locks, u64 cookie,
1158                                         u8 flags, u8 master)
1159 {
1160         /* mres here is one full page */
1161         clear_page(mres);
1162         mres->lockname_len = namelen;
1163         memcpy(mres->lockname, lockname, namelen);
1164         mres->num_locks = 0;
1165         mres->total_locks = cpu_to_be32(total_locks);
1166         mres->mig_cookie = cpu_to_be64(cookie);
1167         mres->flags = flags;
1168         mres->master = master;
1169 }
1170
1171 static void dlm_prepare_lvb_for_migration(struct dlm_lock *lock,
1172                                           struct dlm_migratable_lockres *mres,
1173                                           int queue)
1174 {
1175         if (!lock->lksb)
1176                return;
1177
1178         /* Ignore lvb in all locks in the blocked list */
1179         if (queue == DLM_BLOCKED_LIST)
1180                 return;
1181
1182         /* Only consider lvbs in locks with granted EX or PR lock levels */
1183         if (lock->ml.type != LKM_EXMODE && lock->ml.type != LKM_PRMODE)
1184                 return;
1185
1186         if (dlm_lvb_is_empty(mres->lvb)) {
1187                 memcpy(mres->lvb, lock->lksb->lvb, DLM_LVB_LEN);
1188                 return;
1189         }
1190
1191         /* Ensure the lvb copied for migration matches in other valid locks */
1192         if (!memcmp(mres->lvb, lock->lksb->lvb, DLM_LVB_LEN))
1193                 return;
1194
1195         mlog(ML_ERROR, "Mismatched lvb in lock cookie=%u:%llu, name=%.*s, "
1196              "node=%u\n",
1197              dlm_get_lock_cookie_node(be64_to_cpu(lock->ml.cookie)),
1198              dlm_get_lock_cookie_seq(be64_to_cpu(lock->ml.cookie)),
1199              lock->lockres->lockname.len, lock->lockres->lockname.name,
1200              lock->ml.node);
1201         dlm_print_one_lock_resource(lock->lockres);
1202         BUG();
1203 }
1204
1205 /* returns 1 if this lock fills the network structure,
1206  * 0 otherwise */
1207 static int dlm_add_lock_to_array(struct dlm_lock *lock,
1208                                  struct dlm_migratable_lockres *mres, int queue)
1209 {
1210         struct dlm_migratable_lock *ml;
1211         int lock_num = mres->num_locks;
1212
1213         ml = &(mres->ml[lock_num]);
1214         ml->cookie = lock->ml.cookie;
1215         ml->type = lock->ml.type;
1216         ml->convert_type = lock->ml.convert_type;
1217         ml->highest_blocked = lock->ml.highest_blocked;
1218         ml->list = queue;
1219         if (lock->lksb) {
1220                 ml->flags = lock->lksb->flags;
1221                 dlm_prepare_lvb_for_migration(lock, mres, queue);
1222         }
1223         ml->node = lock->ml.node;
1224         mres->num_locks++;
1225         /* we reached the max, send this network message */
1226         if (mres->num_locks == DLM_MAX_MIGRATABLE_LOCKS)
1227                 return 1;
1228         return 0;
1229 }
1230
1231 static void dlm_add_dummy_lock(struct dlm_ctxt *dlm,
1232                                struct dlm_migratable_lockres *mres)
1233 {
1234         struct dlm_lock dummy;
1235         memset(&dummy, 0, sizeof(dummy));
1236         dummy.ml.cookie = 0;
1237         dummy.ml.type = LKM_IVMODE;
1238         dummy.ml.convert_type = LKM_IVMODE;
1239         dummy.ml.highest_blocked = LKM_IVMODE;
1240         dummy.lksb = NULL;
1241         dummy.ml.node = dlm->node_num;
1242         dlm_add_lock_to_array(&dummy, mres, DLM_BLOCKED_LIST);
1243 }
1244
1245 static inline int dlm_is_dummy_lock(struct dlm_ctxt *dlm,
1246                                     struct dlm_migratable_lock *ml,
1247                                     u8 *nodenum)
1248 {
1249         if (unlikely(ml->cookie == 0 &&
1250             ml->type == LKM_IVMODE &&
1251             ml->convert_type == LKM_IVMODE &&
1252             ml->highest_blocked == LKM_IVMODE &&
1253             ml->list == DLM_BLOCKED_LIST)) {
1254                 *nodenum = ml->node;
1255                 return 1;
1256         }
1257         return 0;
1258 }
1259
1260 int dlm_send_one_lockres(struct dlm_ctxt *dlm, struct dlm_lock_resource *res,
1261                          struct dlm_migratable_lockres *mres,
1262                          u8 send_to, u8 flags)
1263 {
1264         struct list_head *queue;
1265         int total_locks, i;
1266         u64 mig_cookie = 0;
1267         struct dlm_lock *lock;
1268         int ret = 0;
1269
1270         BUG_ON(!(flags & (DLM_MRES_RECOVERY|DLM_MRES_MIGRATION)));
1271
1272         mlog(0, "sending to %u\n", send_to);
1273
1274         total_locks = dlm_num_locks_in_lockres(res);
1275         if (total_locks > DLM_MAX_MIGRATABLE_LOCKS) {
1276                 /* rare, but possible */
1277                 mlog(0, "argh.  lockres has %d locks.  this will "
1278                           "require more than one network packet to "
1279                           "migrate\n", total_locks);
1280                 mig_cookie = dlm_get_next_mig_cookie();
1281         }
1282
1283         dlm_init_migratable_lockres(mres, res->lockname.name,
1284                                     res->lockname.len, total_locks,
1285                                     mig_cookie, flags, res->owner);
1286
1287         total_locks = 0;
1288         for (i=DLM_GRANTED_LIST; i<=DLM_BLOCKED_LIST; i++) {
1289                 queue = dlm_list_idx_to_ptr(res, i);
1290                 list_for_each_entry(lock, queue, list) {
1291                         /* add another lock. */
1292                         total_locks++;
1293                         if (!dlm_add_lock_to_array(lock, mres, i))
1294                                 continue;
1295
1296                         /* this filled the lock message,
1297                          * we must send it immediately. */
1298                         ret = dlm_send_mig_lockres_msg(dlm, mres, send_to,
1299                                                        res, total_locks);
1300                         if (ret < 0)
1301                                 goto error;
1302                 }
1303         }
1304         if (total_locks == 0) {
1305                 /* send a dummy lock to indicate a mastery reference only */
1306                 mlog(0, "%s:%.*s: sending dummy lock to %u, %s\n",
1307                      dlm->name, res->lockname.len, res->lockname.name,
1308                      send_to, flags & DLM_MRES_RECOVERY ? "recovery" :
1309                      "migration");
1310                 dlm_add_dummy_lock(dlm, mres);
1311         }
1312         /* flush any remaining locks */
1313         ret = dlm_send_mig_lockres_msg(dlm, mres, send_to, res, total_locks);
1314         if (ret < 0)
1315                 goto error;
1316         return ret;
1317
1318 error:
1319         mlog(ML_ERROR, "%s: dlm_send_mig_lockres_msg returned %d\n",
1320              dlm->name, ret);
1321         if (!dlm_is_host_down(ret))
1322                 BUG();
1323         mlog(0, "%s: node %u went down while sending %s "
1324              "lockres %.*s\n", dlm->name, send_to,
1325              flags & DLM_MRES_RECOVERY ?  "recovery" : "migration",
1326              res->lockname.len, res->lockname.name);
1327         return ret;
1328 }
1329
1330
1331
1332 /*
1333  * this message will contain no more than one page worth of
1334  * recovery data, and it will work on only one lockres.
1335  * there may be many locks in this page, and we may need to wait
1336  * for additional packets to complete all the locks (rare, but
1337  * possible).
1338  */
1339 /*
1340  * NOTE: the allocation error cases here are scary
1341  * we really cannot afford to fail an alloc in recovery
1342  * do we spin?  returning an error only delays the problem really
1343  */
1344
1345 int dlm_mig_lockres_handler(struct o2net_msg *msg, u32 len, void *data,
1346                             void **ret_data)
1347 {
1348         struct dlm_ctxt *dlm = data;
1349         struct dlm_migratable_lockres *mres =
1350                 (struct dlm_migratable_lockres *)msg->buf;
1351         int ret = 0;
1352         u8 real_master;
1353         u8 extra_refs = 0;
1354         char *buf = NULL;
1355         struct dlm_work_item *item = NULL;
1356         struct dlm_lock_resource *res = NULL;
1357
1358         if (!dlm_grab(dlm))
1359                 return -EINVAL;
1360
1361         BUG_ON(!(mres->flags & (DLM_MRES_RECOVERY|DLM_MRES_MIGRATION)));
1362
1363         real_master = mres->master;
1364         if (real_master == DLM_LOCK_RES_OWNER_UNKNOWN) {
1365                 /* cannot migrate a lockres with no master */
1366                 BUG_ON(!(mres->flags & DLM_MRES_RECOVERY));
1367         }
1368
1369         mlog(0, "%s message received from node %u\n",
1370                   (mres->flags & DLM_MRES_RECOVERY) ?
1371                   "recovery" : "migration", mres->master);
1372         if (mres->flags & DLM_MRES_ALL_DONE)
1373                 mlog(0, "all done flag.  all lockres data received!\n");
1374
1375         ret = -ENOMEM;
1376         buf = kmalloc(be16_to_cpu(msg->data_len), GFP_NOFS);
1377         item = kzalloc(sizeof(*item), GFP_NOFS);
1378         if (!buf || !item)
1379                 goto leave;
1380
1381         /* lookup the lock to see if we have a secondary queue for this
1382          * already...  just add the locks in and this will have its owner
1383          * and RECOVERY flag changed when it completes. */
1384         res = dlm_lookup_lockres(dlm, mres->lockname, mres->lockname_len);
1385         if (res) {
1386                 /* this will get a ref on res */
1387                 /* mark it as recovering/migrating and hash it */
1388                 spin_lock(&res->spinlock);
1389                 if (mres->flags & DLM_MRES_RECOVERY) {
1390                         res->state |= DLM_LOCK_RES_RECOVERING;
1391                 } else {
1392                         if (res->state & DLM_LOCK_RES_MIGRATING) {
1393                                 /* this is at least the second
1394                                  * lockres message */
1395                                 mlog(0, "lock %.*s is already migrating\n",
1396                                           mres->lockname_len,
1397                                           mres->lockname);
1398                         } else if (res->state & DLM_LOCK_RES_RECOVERING) {
1399                                 /* caller should BUG */
1400                                 mlog(ML_ERROR, "node is attempting to migrate "
1401                                      "lock %.*s, but marked as recovering!\n",
1402                                      mres->lockname_len, mres->lockname);
1403                                 ret = -EFAULT;
1404                                 spin_unlock(&res->spinlock);
1405                                 goto leave;
1406                         }
1407                         res->state |= DLM_LOCK_RES_MIGRATING;
1408                 }
1409                 spin_unlock(&res->spinlock);
1410         } else {
1411                 /* need to allocate, just like if it was
1412                  * mastered here normally  */
1413                 res = dlm_new_lockres(dlm, mres->lockname, mres->lockname_len);
1414                 if (!res)
1415                         goto leave;
1416
1417                 /* to match the ref that we would have gotten if
1418                  * dlm_lookup_lockres had succeeded */
1419                 dlm_lockres_get(res);
1420
1421                 /* mark it as recovering/migrating and hash it */
1422                 if (mres->flags & DLM_MRES_RECOVERY)
1423                         res->state |= DLM_LOCK_RES_RECOVERING;
1424                 else
1425                         res->state |= DLM_LOCK_RES_MIGRATING;
1426
1427                 spin_lock(&dlm->spinlock);
1428                 __dlm_insert_lockres(dlm, res);
1429                 spin_unlock(&dlm->spinlock);
1430
1431                 /* Add an extra ref for this lock-less lockres lest the
1432                  * dlm_thread purges it before we get the chance to add
1433                  * locks to it */
1434                 dlm_lockres_get(res);
1435
1436                 /* There are three refs that need to be put.
1437                  * 1. Taken above.
1438                  * 2. kref_init in dlm_new_lockres()->dlm_init_lockres().
1439                  * 3. dlm_lookup_lockres()
1440                  * The first one is handled at the end of this function. The
1441                  * other two are handled in the worker thread after locks have
1442                  * been attached. Yes, we don't wait for purge time to match
1443                  * kref_init. The lockres will still have atleast one ref
1444                  * added because it is in the hash __dlm_insert_lockres() */
1445                 extra_refs++;
1446
1447                 /* now that the new lockres is inserted,
1448                  * make it usable by other processes */
1449                 spin_lock(&res->spinlock);
1450                 res->state &= ~DLM_LOCK_RES_IN_PROGRESS;
1451                 spin_unlock(&res->spinlock);
1452                 wake_up(&res->wq);
1453         }
1454
1455         /* at this point we have allocated everything we need,
1456          * and we have a hashed lockres with an extra ref and
1457          * the proper res->state flags. */
1458         ret = 0;
1459         spin_lock(&res->spinlock);
1460         /* drop this either when master requery finds a different master
1461          * or when a lock is added by the recovery worker */
1462         dlm_lockres_grab_inflight_ref(dlm, res);
1463         if (mres->master == DLM_LOCK_RES_OWNER_UNKNOWN) {
1464                 /* migration cannot have an unknown master */
1465                 BUG_ON(!(mres->flags & DLM_MRES_RECOVERY));
1466                 mlog(0, "recovery has passed me a lockres with an "
1467                           "unknown owner.. will need to requery: "
1468                           "%.*s\n", mres->lockname_len, mres->lockname);
1469         } else {
1470                 /* take a reference now to pin the lockres, drop it
1471                  * when locks are added in the worker */
1472                 dlm_change_lockres_owner(dlm, res, dlm->node_num);
1473         }
1474         spin_unlock(&res->spinlock);
1475
1476         /* queue up work for dlm_mig_lockres_worker */
1477         dlm_grab(dlm);  /* get an extra ref for the work item */
1478         memcpy(buf, msg->buf, be16_to_cpu(msg->data_len));  /* copy the whole message */
1479         dlm_init_work_item(dlm, item, dlm_mig_lockres_worker, buf);
1480         item->u.ml.lockres = res; /* already have a ref */
1481         item->u.ml.real_master = real_master;
1482         item->u.ml.extra_ref = extra_refs;
1483         spin_lock(&dlm->work_lock);
1484         list_add_tail(&item->list, &dlm->work_list);
1485         spin_unlock(&dlm->work_lock);
1486         queue_work(dlm->dlm_worker, &dlm->dispatched_work);
1487
1488 leave:
1489         /* One extra ref taken needs to be put here */
1490         if (extra_refs)
1491                 dlm_lockres_put(res);
1492
1493         dlm_put(dlm);
1494         if (ret < 0) {
1495                 if (buf)
1496                         kfree(buf);
1497                 if (item)
1498                         kfree(item);
1499         }
1500
1501         mlog_exit(ret);
1502         return ret;
1503 }
1504
1505
1506 static void dlm_mig_lockres_worker(struct dlm_work_item *item, void *data)
1507 {
1508         struct dlm_ctxt *dlm;
1509         struct dlm_migratable_lockres *mres;
1510         int ret = 0;
1511         struct dlm_lock_resource *res;
1512         u8 real_master;
1513         u8 extra_ref;
1514
1515         dlm = item->dlm;
1516         mres = (struct dlm_migratable_lockres *)data;
1517
1518         res = item->u.ml.lockres;
1519         real_master = item->u.ml.real_master;
1520         extra_ref = item->u.ml.extra_ref;
1521
1522         if (real_master == DLM_LOCK_RES_OWNER_UNKNOWN) {
1523                 /* this case is super-rare. only occurs if
1524                  * node death happens during migration. */
1525 again:
1526                 ret = dlm_lockres_master_requery(dlm, res, &real_master);
1527                 if (ret < 0) {
1528                         mlog(0, "dlm_lockres_master_requery ret=%d\n",
1529                                   ret);
1530                         goto again;
1531                 }
1532                 if (real_master == DLM_LOCK_RES_OWNER_UNKNOWN) {
1533                         mlog(0, "lockres %.*s not claimed.  "
1534                                    "this node will take it.\n",
1535                                    res->lockname.len, res->lockname.name);
1536                 } else {
1537                         spin_lock(&res->spinlock);
1538                         dlm_lockres_drop_inflight_ref(dlm, res);
1539                         spin_unlock(&res->spinlock);
1540                         mlog(0, "master needs to respond to sender "
1541                                   "that node %u still owns %.*s\n",
1542                                   real_master, res->lockname.len,
1543                                   res->lockname.name);
1544                         /* cannot touch this lockres */
1545                         goto leave;
1546                 }
1547         }
1548
1549         ret = dlm_process_recovery_data(dlm, res, mres);
1550         if (ret < 0)
1551                 mlog(0, "dlm_process_recovery_data returned  %d\n", ret);
1552         else
1553                 mlog(0, "dlm_process_recovery_data succeeded\n");
1554
1555         if ((mres->flags & (DLM_MRES_MIGRATION|DLM_MRES_ALL_DONE)) ==
1556                            (DLM_MRES_MIGRATION|DLM_MRES_ALL_DONE)) {
1557                 ret = dlm_finish_migration(dlm, res, mres->master);
1558                 if (ret < 0)
1559                         mlog_errno(ret);
1560         }
1561
1562 leave:
1563         /* See comment in dlm_mig_lockres_handler() */
1564         if (res) {
1565                 if (extra_ref)
1566                         dlm_lockres_put(res);
1567                 dlm_lockres_put(res);
1568         }
1569         kfree(data);
1570         mlog_exit(ret);
1571 }
1572
1573
1574
1575 static int dlm_lockres_master_requery(struct dlm_ctxt *dlm,
1576                                       struct dlm_lock_resource *res,
1577                                       u8 *real_master)
1578 {
1579         struct dlm_node_iter iter;
1580         int nodenum;
1581         int ret = 0;
1582
1583         *real_master = DLM_LOCK_RES_OWNER_UNKNOWN;
1584
1585         /* we only reach here if one of the two nodes in a
1586          * migration died while the migration was in progress.
1587          * at this point we need to requery the master.  we
1588          * know that the new_master got as far as creating
1589          * an mle on at least one node, but we do not know
1590          * if any nodes had actually cleared the mle and set
1591          * the master to the new_master.  the old master
1592          * is supposed to set the owner to UNKNOWN in the
1593          * event of a new_master death, so the only possible
1594          * responses that we can get from nodes here are
1595          * that the master is new_master, or that the master
1596          * is UNKNOWN.
1597          * if all nodes come back with UNKNOWN then we know
1598          * the lock needs remastering here.
1599          * if any node comes back with a valid master, check
1600          * to see if that master is the one that we are
1601          * recovering.  if so, then the new_master died and
1602          * we need to remaster this lock.  if not, then the
1603          * new_master survived and that node will respond to
1604          * other nodes about the owner.
1605          * if there is an owner, this node needs to dump this
1606          * lockres and alert the sender that this lockres
1607          * was rejected. */
1608         spin_lock(&dlm->spinlock);
1609         dlm_node_iter_init(dlm->domain_map, &iter);
1610         spin_unlock(&dlm->spinlock);
1611
1612         while ((nodenum = dlm_node_iter_next(&iter)) >= 0) {
1613                 /* do not send to self */
1614                 if (nodenum == dlm->node_num)
1615                         continue;
1616                 ret = dlm_do_master_requery(dlm, res, nodenum, real_master);
1617                 if (ret < 0) {
1618                         mlog_errno(ret);
1619                         if (!dlm_is_host_down(ret))
1620                                 BUG();
1621                         /* host is down, so answer for that node would be
1622                          * DLM_LOCK_RES_OWNER_UNKNOWN.  continue. */
1623                 }
1624                 if (*real_master != DLM_LOCK_RES_OWNER_UNKNOWN) {
1625                         mlog(0, "lock master is %u\n", *real_master);
1626                         break;
1627                 }
1628         }
1629         return ret;
1630 }
1631
1632
1633 int dlm_do_master_requery(struct dlm_ctxt *dlm, struct dlm_lock_resource *res,
1634                           u8 nodenum, u8 *real_master)
1635 {
1636         int ret = -EINVAL;
1637         struct dlm_master_requery req;
1638         int status = DLM_LOCK_RES_OWNER_UNKNOWN;
1639
1640         memset(&req, 0, sizeof(req));
1641         req.node_idx = dlm->node_num;
1642         req.namelen = res->lockname.len;
1643         memcpy(req.name, res->lockname.name, res->lockname.len);
1644
1645         ret = o2net_send_message(DLM_MASTER_REQUERY_MSG, dlm->key,
1646                                  &req, sizeof(req), nodenum, &status);
1647         /* XXX: negative status not handled properly here. */
1648         if (ret < 0)
1649                 mlog(ML_ERROR, "Error %d when sending message %u (key "
1650                      "0x%x) to node %u\n", ret, DLM_MASTER_REQUERY_MSG,
1651                      dlm->key, nodenum);
1652         else {
1653                 BUG_ON(status < 0);
1654                 BUG_ON(status > DLM_LOCK_RES_OWNER_UNKNOWN);
1655                 *real_master = (u8) (status & 0xff);
1656                 mlog(0, "node %u responded to master requery with %u\n",
1657                           nodenum, *real_master);
1658                 ret = 0;
1659         }
1660         return ret;
1661 }
1662
1663
1664 /* this function cannot error, so unless the sending
1665  * or receiving of the message failed, the owner can
1666  * be trusted */
1667 int dlm_master_requery_handler(struct o2net_msg *msg, u32 len, void *data,
1668                                void **ret_data)
1669 {
1670         struct dlm_ctxt *dlm = data;
1671         struct dlm_master_requery *req = (struct dlm_master_requery *)msg->buf;
1672         struct dlm_lock_resource *res = NULL;
1673         unsigned int hash;
1674         int master = DLM_LOCK_RES_OWNER_UNKNOWN;
1675         u32 flags = DLM_ASSERT_MASTER_REQUERY;
1676
1677         if (!dlm_grab(dlm)) {
1678                 /* since the domain has gone away on this
1679                  * node, the proper response is UNKNOWN */
1680                 return master;
1681         }
1682
1683         hash = dlm_lockid_hash(req->name, req->namelen);
1684
1685         spin_lock(&dlm->spinlock);
1686         res = __dlm_lookup_lockres(dlm, req->name, req->namelen, hash);
1687         if (res) {
1688                 spin_lock(&res->spinlock);
1689                 master = res->owner;
1690                 if (master == dlm->node_num) {
1691                         int ret = dlm_dispatch_assert_master(dlm, res,
1692                                                              0, 0, flags);
1693                         if (ret < 0) {
1694                                 mlog_errno(-ENOMEM);
1695                                 /* retry!? */
1696                                 BUG();
1697                         }
1698                 } else /* put.. incase we are not the master */
1699                         dlm_lockres_put(res);
1700                 spin_unlock(&res->spinlock);
1701         }
1702         spin_unlock(&dlm->spinlock);
1703
1704         dlm_put(dlm);
1705         return master;
1706 }
1707
1708 static inline struct list_head *
1709 dlm_list_num_to_pointer(struct dlm_lock_resource *res, int list_num)
1710 {
1711         struct list_head *ret;
1712         BUG_ON(list_num < 0);
1713         BUG_ON(list_num > 2);
1714         ret = &(res->granted);
1715         ret += list_num;
1716         return ret;
1717 }
1718 /* TODO: do ast flush business
1719  * TODO: do MIGRATING and RECOVERING spinning
1720  */
1721
1722 /*
1723 * NOTE about in-flight requests during migration:
1724 *
1725 * Before attempting the migrate, the master has marked the lockres as
1726 * MIGRATING and then flushed all of its pending ASTS.  So any in-flight
1727 * requests either got queued before the MIGRATING flag got set, in which
1728 * case the lock data will reflect the change and a return message is on
1729 * the way, or the request failed to get in before MIGRATING got set.  In
1730 * this case, the caller will be told to spin and wait for the MIGRATING
1731 * flag to be dropped, then recheck the master.
1732 * This holds true for the convert, cancel and unlock cases, and since lvb
1733 * updates are tied to these same messages, it applies to lvb updates as
1734 * well.  For the lock case, there is no way a lock can be on the master
1735 * queue and not be on the secondary queue since the lock is always added
1736 * locally first.  This means that the new target node will never be sent
1737 * a lock that he doesn't already have on the list.
1738 * In total, this means that the local lock is correct and should not be
1739 * updated to match the one sent by the master.  Any messages sent back
1740 * from the master before the MIGRATING flag will bring the lock properly
1741 * up-to-date, and the change will be ordered properly for the waiter.
1742 * We will *not* attempt to modify the lock underneath the waiter.
1743 */
1744
1745 static int dlm_process_recovery_data(struct dlm_ctxt *dlm,
1746                                      struct dlm_lock_resource *res,
1747                                      struct dlm_migratable_lockres *mres)
1748 {
1749         struct dlm_migratable_lock *ml;
1750         struct list_head *queue;
1751         struct list_head *tmpq = NULL;
1752         struct dlm_lock *newlock = NULL;
1753         struct dlm_lockstatus *lksb = NULL;
1754         int ret = 0;
1755         int i, j, bad;
1756         struct dlm_lock *lock = NULL;
1757         u8 from = O2NM_MAX_NODES;
1758         unsigned int added = 0;
1759         __be64 c;
1760
1761         mlog(0, "running %d locks for this lockres\n", mres->num_locks);
1762         for (i=0; i<mres->num_locks; i++) {
1763                 ml = &(mres->ml[i]);
1764
1765                 if (dlm_is_dummy_lock(dlm, ml, &from)) {
1766                         /* placeholder, just need to set the refmap bit */
1767                         BUG_ON(mres->num_locks != 1);
1768                         mlog(0, "%s:%.*s: dummy lock for %u\n",
1769                              dlm->name, mres->lockname_len, mres->lockname,
1770                              from);
1771                         spin_lock(&res->spinlock);
1772                         dlm_lockres_set_refmap_bit(from, res);
1773                         spin_unlock(&res->spinlock);
1774                         added++;
1775                         break;
1776                 }
1777                 BUG_ON(ml->highest_blocked != LKM_IVMODE);
1778                 newlock = NULL;
1779                 lksb = NULL;
1780
1781                 queue = dlm_list_num_to_pointer(res, ml->list);
1782                 tmpq = NULL;
1783
1784                 /* if the lock is for the local node it needs to
1785                  * be moved to the proper location within the queue.
1786                  * do not allocate a new lock structure. */
1787                 if (ml->node == dlm->node_num) {
1788                         /* MIGRATION ONLY! */
1789                         BUG_ON(!(mres->flags & DLM_MRES_MIGRATION));
1790
1791                         spin_lock(&res->spinlock);
1792                         for (j = DLM_GRANTED_LIST; j <= DLM_BLOCKED_LIST; j++) {
1793                                 tmpq = dlm_list_idx_to_ptr(res, j);
1794                                 list_for_each_entry(lock, tmpq, list) {
1795                                         if (lock->ml.cookie != ml->cookie)
1796                                                 lock = NULL;
1797                                         else
1798                                                 break;
1799                                 }
1800                                 if (lock)
1801                                         break;
1802                         }
1803
1804                         /* lock is always created locally first, and
1805                          * destroyed locally last.  it must be on the list */
1806                         if (!lock) {
1807                                 c = ml->cookie;
1808                                 mlog(ML_ERROR, "Could not find local lock "
1809                                                "with cookie %u:%llu, node %u, "
1810                                                "list %u, flags 0x%x, type %d, "
1811                                                "conv %d, highest blocked %d\n",
1812                                      dlm_get_lock_cookie_node(be64_to_cpu(c)),
1813                                      dlm_get_lock_cookie_seq(be64_to_cpu(c)),
1814                                      ml->node, ml->list, ml->flags, ml->type,
1815                                      ml->convert_type, ml->highest_blocked);
1816                                 __dlm_print_one_lock_resource(res);
1817                                 BUG();
1818                         }
1819
1820                         if (lock->ml.node != ml->node) {
1821                                 c = lock->ml.cookie;
1822                                 mlog(ML_ERROR, "Mismatched node# in lock "
1823                                      "cookie %u:%llu, name %.*s, node %u\n",
1824                                      dlm_get_lock_cookie_node(be64_to_cpu(c)),
1825                                      dlm_get_lock_cookie_seq(be64_to_cpu(c)),
1826                                      res->lockname.len, res->lockname.name,
1827                                      lock->ml.node);
1828                                 c = ml->cookie;
1829                                 mlog(ML_ERROR, "Migrate lock cookie %u:%llu, "
1830                                      "node %u, list %u, flags 0x%x, type %d, "
1831                                      "conv %d, highest blocked %d\n",
1832                                      dlm_get_lock_cookie_node(be64_to_cpu(c)),
1833                                      dlm_get_lock_cookie_seq(be64_to_cpu(c)),
1834                                      ml->node, ml->list, ml->flags, ml->type,
1835                                      ml->convert_type, ml->highest_blocked);
1836                                 __dlm_print_one_lock_resource(res);
1837                                 BUG();
1838                         }
1839
1840                         if (tmpq != queue) {
1841                                 c = ml->cookie;
1842                                 mlog(0, "Lock cookie %u:%llu was on list %u "
1843                                      "instead of list %u for %.*s\n",
1844                                      dlm_get_lock_cookie_node(be64_to_cpu(c)),
1845                                      dlm_get_lock_cookie_seq(be64_to_cpu(c)),
1846                                      j, ml->list, res->lockname.len,
1847                                      res->lockname.name);
1848                                 __dlm_print_one_lock_resource(res);
1849                                 spin_unlock(&res->spinlock);
1850                                 continue;
1851                         }
1852
1853                         /* see NOTE above about why we do not update
1854                          * to match the master here */
1855
1856                         /* move the lock to its proper place */
1857                         /* do not alter lock refcount.  switching lists. */
1858                         list_move_tail(&lock->list, queue);
1859                         spin_unlock(&res->spinlock);
1860                         added++;
1861
1862                         mlog(0, "just reordered a local lock!\n");
1863                         continue;
1864                 }
1865
1866                 /* lock is for another node. */
1867                 newlock = dlm_new_lock(ml->type, ml->node,
1868                                        be64_to_cpu(ml->cookie), NULL);
1869                 if (!newlock) {
1870                         ret = -ENOMEM;
1871                         goto leave;
1872                 }
1873                 lksb = newlock->lksb;
1874                 dlm_lock_attach_lockres(newlock, res);
1875
1876                 if (ml->convert_type != LKM_IVMODE) {
1877                         BUG_ON(queue != &res->converting);
1878                         newlock->ml.convert_type = ml->convert_type;
1879                 }
1880                 lksb->flags |= (ml->flags &
1881                                 (DLM_LKSB_PUT_LVB|DLM_LKSB_GET_LVB));
1882
1883                 if (ml->type == LKM_NLMODE)
1884                         goto skip_lvb;
1885
1886                 if (!dlm_lvb_is_empty(mres->lvb)) {
1887                         if (lksb->flags & DLM_LKSB_PUT_LVB) {
1888                                 /* other node was trying to update
1889                                  * lvb when node died.  recreate the
1890                                  * lksb with the updated lvb. */
1891                                 memcpy(lksb->lvb, mres->lvb, DLM_LVB_LEN);
1892                                 /* the lock resource lvb update must happen
1893                                  * NOW, before the spinlock is dropped.
1894                                  * we no longer wait for the AST to update
1895                                  * the lvb. */
1896                                 memcpy(res->lvb, mres->lvb, DLM_LVB_LEN);
1897                         } else {
1898                                 /* otherwise, the node is sending its
1899                                  * most recent valid lvb info */
1900                                 BUG_ON(ml->type != LKM_EXMODE &&
1901                                        ml->type != LKM_PRMODE);
1902                                 if (!dlm_lvb_is_empty(res->lvb) &&
1903                                     (ml->type == LKM_EXMODE ||
1904                                      memcmp(res->lvb, mres->lvb, DLM_LVB_LEN))) {
1905                                         int i;
1906                                         mlog(ML_ERROR, "%s:%.*s: received bad "
1907                                              "lvb! type=%d\n", dlm->name,
1908                                              res->lockname.len,
1909                                              res->lockname.name, ml->type);
1910                                         printk("lockres lvb=[");
1911                                         for (i=0; i<DLM_LVB_LEN; i++)
1912                                                 printk("%02x", res->lvb[i]);
1913                                         printk("]\nmigrated lvb=[");
1914                                         for (i=0; i<DLM_LVB_LEN; i++)
1915                                                 printk("%02x", mres->lvb[i]);
1916                                         printk("]\n");
1917                                         dlm_print_one_lock_resource(res);
1918                                         BUG();
1919                                 }
1920                                 memcpy(res->lvb, mres->lvb, DLM_LVB_LEN);
1921                         }
1922                 }
1923 skip_lvb:
1924
1925                 /* NOTE:
1926                  * wrt lock queue ordering and recovery:
1927                  *    1. order of locks on granted queue is
1928                  *       meaningless.
1929                  *    2. order of locks on converting queue is
1930                  *       LOST with the node death.  sorry charlie.
1931                  *    3. order of locks on the blocked queue is
1932                  *       also LOST.
1933                  * order of locks does not affect integrity, it
1934                  * just means that a lock request may get pushed
1935                  * back in line as a result of the node death.
1936                  * also note that for a given node the lock order
1937                  * for its secondary queue locks is preserved
1938                  * relative to each other, but clearly *not*
1939                  * preserved relative to locks from other nodes.
1940                  */
1941                 bad = 0;
1942                 spin_lock(&res->spinlock);
1943                 list_for_each_entry(lock, queue, list) {
1944                         if (lock->ml.cookie == ml->cookie) {
1945                                 c = lock->ml.cookie;
1946                                 mlog(ML_ERROR, "%s:%.*s: %u:%llu: lock already "
1947                                      "exists on this lockres!\n", dlm->name,
1948                                      res->lockname.len, res->lockname.name,
1949                                      dlm_get_lock_cookie_node(be64_to_cpu(c)),
1950                                      dlm_get_lock_cookie_seq(be64_to_cpu(c)));
1951
1952                                 mlog(ML_NOTICE, "sent lock: type=%d, conv=%d, "
1953                                      "node=%u, cookie=%u:%llu, queue=%d\n",
1954                                      ml->type, ml->convert_type, ml->node,
1955                                      dlm_get_lock_cookie_node(be64_to_cpu(ml->cookie)),
1956                                      dlm_get_lock_cookie_seq(be64_to_cpu(ml->cookie)),
1957                                      ml->list);
1958
1959                                 __dlm_print_one_lock_resource(res);
1960                                 bad = 1;
1961                                 break;
1962                         }
1963                 }
1964                 if (!bad) {
1965                         dlm_lock_get(newlock);
1966                         list_add_tail(&newlock->list, queue);
1967                         mlog(0, "%s:%.*s: added lock for node %u, "
1968                              "setting refmap bit\n", dlm->name,
1969                              res->lockname.len, res->lockname.name, ml->node);
1970                         dlm_lockres_set_refmap_bit(ml->node, res);
1971                         added++;
1972                 }
1973                 spin_unlock(&res->spinlock);
1974         }
1975         mlog(0, "done running all the locks\n");
1976
1977 leave:
1978         /* balance the ref taken when the work was queued */
1979         spin_lock(&res->spinlock);
1980         dlm_lockres_drop_inflight_ref(dlm, res);
1981         spin_unlock(&res->spinlock);
1982
1983         if (ret < 0) {
1984                 mlog_errno(ret);
1985                 if (newlock)
1986                         dlm_lock_put(newlock);
1987         }
1988
1989         mlog_exit(ret);
1990         return ret;
1991 }
1992
1993 void dlm_move_lockres_to_recovery_list(struct dlm_ctxt *dlm,
1994                                        struct dlm_lock_resource *res)
1995 {
1996         int i;
1997         struct list_head *queue;
1998         struct dlm_lock *lock, *next;
1999
2000         assert_spin_locked(&dlm->spinlock);
2001         assert_spin_locked(&res->spinlock);
2002         res->state |= DLM_LOCK_RES_RECOVERING;
2003         if (!list_empty(&res->recovering)) {
2004                 mlog(0,
2005                      "Recovering res %s:%.*s, is already on recovery list!\n",
2006                      dlm->name, res->lockname.len, res->lockname.name);
2007                 list_del_init(&res->recovering);
2008                 dlm_lockres_put(res);
2009         }
2010         /* We need to hold a reference while on the recovery list */
2011         dlm_lockres_get(res);
2012         list_add_tail(&res->recovering, &dlm->reco.resources);
2013
2014         /* find any pending locks and put them back on proper list */
2015         for (i=DLM_BLOCKED_LIST; i>=DLM_GRANTED_LIST; i--) {
2016                 queue = dlm_list_idx_to_ptr(res, i);
2017                 list_for_each_entry_safe(lock, next, queue, list) {
2018                         dlm_lock_get(lock);
2019                         if (lock->convert_pending) {
2020                                 /* move converting lock back to granted */
2021                                 BUG_ON(i != DLM_CONVERTING_LIST);
2022                                 mlog(0, "node died with convert pending "
2023                                      "on %.*s. move back to granted list.\n",
2024                                      res->lockname.len, res->lockname.name);
2025                                 dlm_revert_pending_convert(res, lock);
2026                                 lock->convert_pending = 0;
2027                         } else if (lock->lock_pending) {
2028                                 /* remove pending lock requests completely */
2029                                 BUG_ON(i != DLM_BLOCKED_LIST);
2030                                 mlog(0, "node died with lock pending "
2031                                      "on %.*s. remove from blocked list and skip.\n",
2032                                      res->lockname.len, res->lockname.name);
2033                                 /* lock will be floating until ref in
2034                                  * dlmlock_remote is freed after the network
2035                                  * call returns.  ok for it to not be on any
2036                                  * list since no ast can be called
2037                                  * (the master is dead). */
2038                                 dlm_revert_pending_lock(res, lock);
2039                                 lock->lock_pending = 0;
2040                         } else if (lock->unlock_pending) {
2041                                 /* if an unlock was in progress, treat as
2042                                  * if this had completed successfully
2043                                  * before sending this lock state to the
2044                                  * new master.  note that the dlm_unlock
2045                                  * call is still responsible for calling
2046                                  * the unlockast.  that will happen after
2047                                  * the network call times out.  for now,
2048                                  * just move lists to prepare the new
2049                                  * recovery master.  */
2050                                 BUG_ON(i != DLM_GRANTED_LIST);
2051                                 mlog(0, "node died with unlock pending "
2052                                      "on %.*s. remove from blocked list and skip.\n",
2053                                      res->lockname.len, res->lockname.name);
2054                                 dlm_commit_pending_unlock(res, lock);
2055                                 lock->unlock_pending = 0;
2056                         } else if (lock->cancel_pending) {
2057                                 /* if a cancel was in progress, treat as
2058                                  * if this had completed successfully
2059                                  * before sending this lock state to the
2060                                  * new master */
2061                                 BUG_ON(i != DLM_CONVERTING_LIST);
2062                                 mlog(0, "node died with cancel pending "
2063                                      "on %.*s. move back to granted list.\n",
2064                                      res->lockname.len, res->lockname.name);
2065                                 dlm_commit_pending_cancel(res, lock);
2066                                 lock->cancel_pending = 0;
2067                         }
2068                         dlm_lock_put(lock);
2069                 }
2070         }
2071 }
2072
2073
2074
2075 /* removes all recovered locks from the recovery list.
2076  * sets the res->owner to the new master.
2077  * unsets the RECOVERY flag and wakes waiters. */
2078 static void dlm_finish_local_lockres_recovery(struct dlm_ctxt *dlm,
2079                                               u8 dead_node, u8 new_master)
2080 {
2081         int i;
2082         struct hlist_node *hash_iter;
2083         struct hlist_head *bucket;
2084         struct dlm_lock_resource *res, *next;
2085
2086         mlog_entry_void();
2087
2088         assert_spin_locked(&dlm->spinlock);
2089
2090         list_for_each_entry_safe(res, next, &dlm->reco.resources, recovering) {
2091                 if (res->owner == dead_node) {
2092                         list_del_init(&res->recovering);
2093                         spin_lock(&res->spinlock);
2094                         /* new_master has our reference from
2095                          * the lock state sent during recovery */
2096                         dlm_change_lockres_owner(dlm, res, new_master);
2097                         res->state &= ~DLM_LOCK_RES_RECOVERING;
2098                         if (__dlm_lockres_has_locks(res))
2099                                 __dlm_dirty_lockres(dlm, res);
2100                         spin_unlock(&res->spinlock);
2101                         wake_up(&res->wq);
2102                         dlm_lockres_put(res);
2103                 }
2104         }
2105
2106         /* this will become unnecessary eventually, but
2107          * for now we need to run the whole hash, clear
2108          * the RECOVERING state and set the owner
2109          * if necessary */
2110         for (i = 0; i < DLM_HASH_BUCKETS; i++) {
2111                 bucket = dlm_lockres_hash(dlm, i);
2112                 hlist_for_each_entry(res, hash_iter, bucket, hash_node) {
2113                         if (res->state & DLM_LOCK_RES_RECOVERING) {
2114                                 if (res->owner == dead_node) {
2115                                         mlog(0, "(this=%u) res %.*s owner=%u "
2116                                              "was not on recovering list, but "
2117                                              "clearing state anyway\n",
2118                                              dlm->node_num, res->lockname.len,
2119                                              res->lockname.name, new_master);
2120                                 } else if (res->owner == dlm->node_num) {
2121                                         mlog(0, "(this=%u) res %.*s owner=%u "
2122                                              "was not on recovering list, "
2123                                              "owner is THIS node, clearing\n",
2124                                              dlm->node_num, res->lockname.len,
2125                                              res->lockname.name, new_master);
2126                                 } else
2127                                         continue;
2128
2129                                 if (!list_empty(&res->recovering)) {
2130                                         mlog(0, "%s:%.*s: lockres was "
2131                                              "marked RECOVERING, owner=%u\n",
2132                                              dlm->name, res->lockname.len,
2133                                              res->lockname.name, res->owner);
2134                                         list_del_init(&res->recovering);
2135                                         dlm_lockres_put(res);
2136                                 }
2137                                 spin_lock(&res->spinlock);
2138                                 /* new_master has our reference from
2139                                  * the lock state sent during recovery */
2140                                 dlm_change_lockres_owner(dlm, res, new_master);
2141                                 res->state &= ~DLM_LOCK_RES_RECOVERING;
2142                                 if (__dlm_lockres_has_locks(res))
2143                                         __dlm_dirty_lockres(dlm, res);
2144                                 spin_unlock(&res->spinlock);
2145                                 wake_up(&res->wq);
2146                         }
2147                 }
2148         }
2149 }
2150
2151 static inline int dlm_lvb_needs_invalidation(struct dlm_lock *lock, int local)
2152 {
2153         if (local) {
2154                 if (lock->ml.type != LKM_EXMODE &&
2155                     lock->ml.type != LKM_PRMODE)
2156                         return 1;
2157         } else if (lock->ml.type == LKM_EXMODE)
2158                 return 1;
2159         return 0;
2160 }
2161
2162 static void dlm_revalidate_lvb(struct dlm_ctxt *dlm,
2163                                struct dlm_lock_resource *res, u8 dead_node)
2164 {
2165         struct list_head *queue;
2166         struct dlm_lock *lock;
2167         int blank_lvb = 0, local = 0;
2168         int i;
2169         u8 search_node;
2170
2171         assert_spin_locked(&dlm->spinlock);
2172         assert_spin_locked(&res->spinlock);
2173
2174         if (res->owner == dlm->node_num)
2175                 /* if this node owned the lockres, and if the dead node
2176                  * had an EX when he died, blank out the lvb */
2177                 search_node = dead_node;
2178         else {
2179                 /* if this is a secondary lockres, and we had no EX or PR
2180                  * locks granted, we can no longer trust the lvb */
2181                 search_node = dlm->node_num;
2182                 local = 1;  /* check local state for valid lvb */
2183         }
2184
2185         for (i=DLM_GRANTED_LIST; i<=DLM_CONVERTING_LIST; i++) {
2186                 queue = dlm_list_idx_to_ptr(res, i);
2187                 list_for_each_entry(lock, queue, list) {
2188                         if (lock->ml.node == search_node) {
2189                                 if (dlm_lvb_needs_invalidation(lock, local)) {
2190                                         /* zero the lksb lvb and lockres lvb */
2191                                         blank_lvb = 1;
2192                                         memset(lock->lksb->lvb, 0, DLM_LVB_LEN);
2193                                 }
2194                         }
2195                 }
2196         }
2197
2198         if (blank_lvb) {
2199                 mlog(0, "clearing %.*s lvb, dead node %u had EX\n",
2200                      res->lockname.len, res->lockname.name, dead_node);
2201                 memset(res->lvb, 0, DLM_LVB_LEN);
2202         }
2203 }
2204
2205 static void dlm_free_dead_locks(struct dlm_ctxt *dlm,
2206                                 struct dlm_lock_resource *res, u8 dead_node)
2207 {
2208         struct dlm_lock *lock, *next;
2209         unsigned int freed = 0;
2210
2211         /* this node is the lockres master:
2212          * 1) remove any stale locks for the dead node
2213          * 2) if the dead node had an EX when he died, blank out the lvb
2214          */
2215         assert_spin_locked(&dlm->spinlock);
2216         assert_spin_locked(&res->spinlock);
2217
2218         /* We do two dlm_lock_put(). One for removing from list and the other is
2219          * to force the DLM_UNLOCK_FREE_LOCK action so as to free the locks */
2220
2221         /* TODO: check pending_asts, pending_basts here */
2222         list_for_each_entry_safe(lock, next, &res->granted, list) {
2223                 if (lock->ml.node == dead_node) {
2224                         list_del_init(&lock->list);
2225                         dlm_lock_put(lock);
2226                         /* Can't schedule DLM_UNLOCK_FREE_LOCK - do manually */
2227                         dlm_lock_put(lock);
2228                         freed++;
2229                 }
2230         }
2231         list_for_each_entry_safe(lock, next, &res->converting, list) {
2232                 if (lock->ml.node == dead_node) {
2233                         list_del_init(&lock->list);
2234                         dlm_lock_put(lock);
2235                         /* Can't schedule DLM_UNLOCK_FREE_LOCK - do manually */
2236                         dlm_lock_put(lock);
2237                         freed++;
2238                 }
2239         }
2240         list_for_each_entry_safe(lock, next, &res->blocked, list) {
2241                 if (lock->ml.node == dead_node) {
2242                         list_del_init(&lock->list);
2243                         dlm_lock_put(lock);
2244                         /* Can't schedule DLM_UNLOCK_FREE_LOCK - do manually */
2245                         dlm_lock_put(lock);
2246                         freed++;
2247                 }
2248         }
2249
2250         if (freed) {
2251                 mlog(0, "%s:%.*s: freed %u locks for dead node %u, "
2252                      "dropping ref from lockres\n", dlm->name,
2253                      res->lockname.len, res->lockname.name, freed, dead_node);
2254                 if(!test_bit(dead_node, res->refmap)) {
2255                         mlog(ML_ERROR, "%s:%.*s: freed %u locks for dead node %u, "
2256                              "but ref was not set\n", dlm->name,
2257                              res->lockname.len, res->lockname.name, freed, dead_node);
2258                         __dlm_print_one_lock_resource(res);
2259                 }
2260                 dlm_lockres_clear_refmap_bit(dead_node, res);
2261         } else if (test_bit(dead_node, res->refmap)) {
2262                 mlog(0, "%s:%.*s: dead node %u had a ref, but had "
2263                      "no locks and had not purged before dying\n", dlm->name,
2264                      res->lockname.len, res->lockname.name, dead_node);
2265                 dlm_lockres_clear_refmap_bit(dead_node, res);
2266         }
2267
2268         /* do not kick thread yet */
2269         __dlm_dirty_lockres(dlm, res);
2270 }
2271
2272 /* if this node is the recovery master, and there are no
2273  * locks for a given lockres owned by this node that are in
2274  * either PR or EX mode, zero out the lvb before requesting.
2275  *
2276  */
2277
2278
2279 static void dlm_do_local_recovery_cleanup(struct dlm_ctxt *dlm, u8 dead_node)
2280 {
2281         struct hlist_node *iter;
2282         struct dlm_lock_resource *res;
2283         int i;
2284         struct hlist_head *bucket;
2285         struct dlm_lock *lock;
2286
2287
2288         /* purge any stale mles */
2289         dlm_clean_master_list(dlm, dead_node);
2290
2291         /*
2292          * now clean up all lock resources.  there are two rules:
2293          *
2294          * 1) if the dead node was the master, move the lockres
2295          *    to the recovering list.  set the RECOVERING flag.
2296          *    this lockres needs to be cleaned up before it can
2297          *    be used further.
2298          *
2299          * 2) if this node was the master, remove all locks from
2300          *    each of the lockres queues that were owned by the
2301          *    dead node.  once recovery finishes, the dlm thread
2302          *    can be kicked again to see if any ASTs or BASTs
2303          *    need to be fired as a result.
2304          */
2305         for (i = 0; i < DLM_HASH_BUCKETS; i++) {
2306                 bucket = dlm_lockres_hash(dlm, i);
2307                 hlist_for_each_entry(res, iter, bucket, hash_node) {
2308                         /* always prune any $RECOVERY entries for dead nodes,
2309                          * otherwise hangs can occur during later recovery */
2310                         if (dlm_is_recovery_lock(res->lockname.name,
2311                                                  res->lockname.len)) {
2312                                 spin_lock(&res->spinlock);
2313                                 list_for_each_entry(lock, &res->granted, list) {
2314                                         if (lock->ml.node == dead_node) {
2315                                                 mlog(0, "AHA! there was "
2316                                                      "a $RECOVERY lock for dead "
2317                                                      "node %u (%s)!\n",
2318                                                      dead_node, dlm->name);
2319                                                 list_del_init(&lock->list);
2320                                                 dlm_lock_put(lock);
2321                                                 break;
2322                                         }
2323                                 }
2324                                 spin_unlock(&res->spinlock);
2325                                 continue;
2326                         }
2327                         spin_lock(&res->spinlock);
2328                         /* zero the lvb if necessary */
2329                         dlm_revalidate_lvb(dlm, res, dead_node);
2330                         if (res->owner == dead_node) {
2331                                 if (res->state & DLM_LOCK_RES_DROPPING_REF) {
2332                                         mlog(ML_NOTICE, "Ignore %.*s for "
2333                                              "recovery as it is being freed\n",
2334                                              res->lockname.len,
2335                                              res->lockname.name);
2336                                 } else
2337                                         dlm_move_lockres_to_recovery_list(dlm,
2338                                                                           res);
2339
2340                         } else if (res->owner == dlm->node_num) {
2341                                 dlm_free_dead_locks(dlm, res, dead_node);
2342                                 __dlm_lockres_calc_usage(dlm, res);
2343                         }
2344                         spin_unlock(&res->spinlock);
2345                 }
2346         }
2347
2348 }
2349
2350 static void __dlm_hb_node_down(struct dlm_ctxt *dlm, int idx)
2351 {
2352         assert_spin_locked(&dlm->spinlock);
2353
2354         if (dlm->reco.new_master == idx) {
2355                 mlog(0, "%s: recovery master %d just died\n",
2356                      dlm->name, idx);
2357                 if (dlm->reco.state & DLM_RECO_STATE_FINALIZE) {
2358                         /* finalize1 was reached, so it is safe to clear
2359                          * the new_master and dead_node.  that recovery
2360                          * is complete. */
2361                         mlog(0, "%s: dead master %d had reached "
2362                              "finalize1 state, clearing\n", dlm->name, idx);
2363                         dlm->reco.state &= ~DLM_RECO_STATE_FINALIZE;
2364                         __dlm_reset_recovery(dlm);
2365                 }
2366         }
2367
2368         /* Clean up join state on node death. */
2369         if (dlm->joining_node == idx) {
2370                 mlog(0, "Clearing join state for node %u\n", idx);
2371                 __dlm_set_joining_node(dlm, DLM_LOCK_RES_OWNER_UNKNOWN);
2372         }
2373
2374         /* check to see if the node is already considered dead */
2375         if (!test_bit(idx, dlm->live_nodes_map)) {
2376                 mlog(0, "for domain %s, node %d is already dead. "
2377                      "another node likely did recovery already.\n",
2378                      dlm->name, idx);
2379                 return;
2380         }
2381
2382         /* check to see if we do not care about this node */
2383         if (!test_bit(idx, dlm->domain_map)) {
2384                 /* This also catches the case that we get a node down
2385                  * but haven't joined the domain yet. */
2386                 mlog(0, "node %u already removed from domain!\n", idx);
2387                 return;
2388         }
2389
2390         clear_bit(idx, dlm->live_nodes_map);
2391
2392         /* make sure local cleanup occurs before the heartbeat events */
2393         if (!test_bit(idx, dlm->recovery_map))
2394                 dlm_do_local_recovery_cleanup(dlm, idx);
2395
2396         /* notify anything attached to the heartbeat events */
2397         dlm_hb_event_notify_attached(dlm, idx, 0);
2398
2399         mlog(0, "node %u being removed from domain map!\n", idx);
2400         clear_bit(idx, dlm->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_entry("%u\n", dead_node);
2611
2612         mlog(0, "%s: dead node is %u\n", dlm->name, dead_node);
2613
2614         spin_lock(&dlm->spinlock);
2615         dlm_node_iter_init(dlm->domain_map, &iter);
2616         spin_unlock(&dlm->spinlock);
2617
2618         clear_bit(dead_node, iter.node_map);
2619
2620         memset(&br, 0, sizeof(br));
2621         br.node_idx = dlm->node_num;
2622         br.dead_node = dead_node;
2623
2624         while ((nodenum = dlm_node_iter_next(&iter)) >= 0) {
2625                 ret = 0;
2626                 if (nodenum == dead_node) {
2627                         mlog(0, "not sending begin reco to dead node "
2628                                   "%u\n", dead_node);
2629                         continue;
2630                 }
2631                 if (nodenum == dlm->node_num) {
2632                         mlog(0, "not sending begin reco to self\n");
2633                         continue;
2634                 }
2635 retry:
2636                 ret = -EINVAL;
2637                 mlog(0, "attempting to send begin reco msg to %d\n",
2638                           nodenum);
2639                 ret = o2net_send_message(DLM_BEGIN_RECO_MSG, dlm->key,
2640                                          &br, sizeof(br), nodenum, &status);
2641                 /* negative status is handled ok by caller here */
2642                 if (ret >= 0)
2643                         ret = status;
2644                 if (dlm_is_host_down(ret)) {
2645                         /* node is down.  not involved in recovery
2646                          * so just keep going */
2647                         mlog(ML_NOTICE, "%s: node %u was down when sending "
2648                              "begin reco msg (%d)\n", dlm->name, nodenum, ret);
2649                         ret = 0;
2650                 }
2651
2652                 /*
2653                  * Prior to commit aad1b15310b9bcd59fa81ab8f2b1513b59553ea8,
2654                  * dlm_begin_reco_handler() returned EAGAIN and not -EAGAIN.
2655                  * We are handling both for compatibility reasons.
2656                  */
2657                 if (ret == -EAGAIN || ret == EAGAIN) {
2658                         mlog(0, "%s: trying to start recovery of node "
2659                              "%u, but node %u is waiting for last recovery "
2660                              "to complete, backoff for a bit\n", dlm->name,
2661                              dead_node, nodenum);
2662                         msleep(100);
2663                         goto retry;
2664                 }
2665                 if (ret < 0) {
2666                         struct dlm_lock_resource *res;
2667
2668                         /* this is now a serious problem, possibly ENOMEM
2669                          * in the network stack.  must retry */
2670                         mlog_errno(ret);
2671                         mlog(ML_ERROR, "begin reco of dlm %s to node %u "
2672                              "returned %d\n", dlm->name, nodenum, ret);
2673                         res = dlm_lookup_lockres(dlm, DLM_RECOVERY_LOCK_NAME,
2674                                                  DLM_RECOVERY_LOCK_NAME_LEN);
2675                         if (res) {
2676                                 dlm_print_one_lock_resource(res);
2677                                 dlm_lockres_put(res);
2678                         } else {
2679                                 mlog(ML_ERROR, "recovery lock not found\n");
2680                         }
2681                         /* sleep for a bit in hopes that we can avoid
2682                          * another ENOMEM */
2683                         msleep(100);
2684                         goto retry;
2685                 }
2686         }
2687
2688         return ret;
2689 }
2690
2691 int dlm_begin_reco_handler(struct o2net_msg *msg, u32 len, void *data,
2692                            void **ret_data)
2693 {
2694         struct dlm_ctxt *dlm = data;
2695         struct dlm_begin_reco *br = (struct dlm_begin_reco *)msg->buf;
2696
2697         /* ok to return 0, domain has gone away */
2698         if (!dlm_grab(dlm))
2699                 return 0;
2700
2701         spin_lock(&dlm->spinlock);
2702         if (dlm->reco.state & DLM_RECO_STATE_FINALIZE) {
2703                 mlog(0, "%s: node %u wants to recover node %u (%u:%u) "
2704                      "but this node is in finalize state, waiting on finalize2\n",
2705                      dlm->name, br->node_idx, br->dead_node,
2706                      dlm->reco.dead_node, dlm->reco.new_master);
2707                 spin_unlock(&dlm->spinlock);
2708                 return -EAGAIN;
2709         }
2710         spin_unlock(&dlm->spinlock);
2711
2712         mlog(0, "%s: node %u wants to recover node %u (%u:%u)\n",
2713              dlm->name, br->node_idx, br->dead_node,
2714              dlm->reco.dead_node, dlm->reco.new_master);
2715
2716         dlm_fire_domain_eviction_callbacks(dlm, br->dead_node);
2717
2718         spin_lock(&dlm->spinlock);
2719         if (dlm->reco.new_master != O2NM_INVALID_NODE_NUM) {
2720                 if (test_bit(dlm->reco.new_master, dlm->recovery_map)) {
2721                         mlog(0, "%s: new_master %u died, changing "
2722                              "to %u\n", dlm->name, dlm->reco.new_master,
2723                              br->node_idx);
2724                 } else {
2725                         mlog(0, "%s: new_master %u NOT DEAD, changing "
2726                              "to %u\n", dlm->name, dlm->reco.new_master,
2727                              br->node_idx);
2728                         /* may not have seen the new master as dead yet */
2729                 }
2730         }
2731         if (dlm->reco.dead_node != O2NM_INVALID_NODE_NUM) {
2732                 mlog(ML_NOTICE, "%s: dead_node previously set to %u, "
2733                      "node %u changing it to %u\n", dlm->name,
2734                      dlm->reco.dead_node, br->node_idx, br->dead_node);
2735         }
2736         dlm_set_reco_master(dlm, br->node_idx);
2737         dlm_set_reco_dead_node(dlm, br->dead_node);
2738         if (!test_bit(br->dead_node, dlm->recovery_map)) {
2739                 mlog(0, "recovery master %u sees %u as dead, but this "
2740                      "node has not yet.  marking %u as dead\n",
2741                      br->node_idx, br->dead_node, br->dead_node);
2742                 if (!test_bit(br->dead_node, dlm->domain_map) ||
2743                     !test_bit(br->dead_node, dlm->live_nodes_map))
2744                         mlog(0, "%u not in domain/live_nodes map "
2745                              "so setting it in reco map manually\n",
2746                              br->dead_node);
2747                 /* force the recovery cleanup in __dlm_hb_node_down
2748                  * both of these will be cleared in a moment */
2749                 set_bit(br->dead_node, dlm->domain_map);
2750                 set_bit(br->dead_node, dlm->live_nodes_map);
2751                 __dlm_hb_node_down(dlm, br->dead_node);
2752         }
2753         spin_unlock(&dlm->spinlock);
2754
2755         dlm_kick_recovery_thread(dlm);
2756
2757         mlog(0, "%s: recovery started by node %u, for %u (%u:%u)\n",
2758              dlm->name, br->node_idx, br->dead_node,
2759              dlm->reco.dead_node, dlm->reco.new_master);
2760
2761         dlm_put(dlm);
2762         return 0;
2763 }
2764
2765 #define DLM_FINALIZE_STAGE2  0x01
2766 static int dlm_send_finalize_reco_message(struct dlm_ctxt *dlm)
2767 {
2768         int ret = 0;
2769         struct dlm_finalize_reco fr;
2770         struct dlm_node_iter iter;
2771         int nodenum;
2772         int status;
2773         int stage = 1;
2774
2775         mlog(0, "finishing recovery for node %s:%u, "
2776              "stage %d\n", dlm->name, dlm->reco.dead_node, stage);
2777
2778         spin_lock(&dlm->spinlock);
2779         dlm_node_iter_init(dlm->domain_map, &iter);
2780         spin_unlock(&dlm->spinlock);
2781
2782 stage2:
2783         memset(&fr, 0, sizeof(fr));
2784         fr.node_idx = dlm->node_num;
2785         fr.dead_node = dlm->reco.dead_node;
2786         if (stage == 2)
2787                 fr.flags |= DLM_FINALIZE_STAGE2;
2788
2789         while ((nodenum = dlm_node_iter_next(&iter)) >= 0) {
2790                 if (nodenum == dlm->node_num)
2791                         continue;
2792                 ret = o2net_send_message(DLM_FINALIZE_RECO_MSG, dlm->key,
2793                                          &fr, sizeof(fr), nodenum, &status);
2794                 if (ret >= 0)
2795                         ret = status;
2796                 if (ret < 0) {
2797                         mlog(ML_ERROR, "Error %d when sending message %u (key "
2798                              "0x%x) to node %u\n", ret, DLM_FINALIZE_RECO_MSG,
2799                              dlm->key, nodenum);
2800                         if (dlm_is_host_down(ret)) {
2801                                 /* this has no effect on this recovery
2802                                  * session, so set the status to zero to
2803                                  * finish out the last recovery */
2804                                 mlog(ML_ERROR, "node %u went down after this "
2805                                      "node finished recovery.\n", nodenum);
2806                                 ret = 0;
2807                                 continue;
2808                         }
2809                         break;
2810                 }
2811         }
2812         if (stage == 1) {
2813                 /* reset the node_iter back to the top and send finalize2 */
2814                 iter.curnode = -1;
2815                 stage = 2;
2816                 goto stage2;
2817         }
2818
2819         return ret;
2820 }
2821
2822 int dlm_finalize_reco_handler(struct o2net_msg *msg, u32 len, void *data,
2823                               void **ret_data)
2824 {
2825         struct dlm_ctxt *dlm = data;
2826         struct dlm_finalize_reco *fr = (struct dlm_finalize_reco *)msg->buf;
2827         int stage = 1;
2828
2829         /* ok to return 0, domain has gone away */
2830         if (!dlm_grab(dlm))
2831                 return 0;
2832
2833         if (fr->flags & DLM_FINALIZE_STAGE2)
2834                 stage = 2;
2835
2836         mlog(0, "%s: node %u finalizing recovery stage%d of "
2837              "node %u (%u:%u)\n", dlm->name, fr->node_idx, stage,
2838              fr->dead_node, dlm->reco.dead_node, dlm->reco.new_master);
2839
2840         spin_lock(&dlm->spinlock);
2841
2842         if (dlm->reco.new_master != fr->node_idx) {
2843                 mlog(ML_ERROR, "node %u sent recovery finalize msg, but node "
2844                      "%u is supposed to be the new master, dead=%u\n",
2845                      fr->node_idx, dlm->reco.new_master, fr->dead_node);
2846                 BUG();
2847         }
2848         if (dlm->reco.dead_node != fr->dead_node) {
2849                 mlog(ML_ERROR, "node %u sent recovery finalize msg for dead "
2850                      "node %u, but node %u is supposed to be dead\n",
2851                      fr->node_idx, fr->dead_node, dlm->reco.dead_node);
2852                 BUG();
2853         }
2854
2855         switch (stage) {
2856                 case 1:
2857                         dlm_finish_local_lockres_recovery(dlm, fr->dead_node, fr->node_idx);
2858                         if (dlm->reco.state & DLM_RECO_STATE_FINALIZE) {
2859                                 mlog(ML_ERROR, "%s: received finalize1 from "
2860                                      "new master %u for dead node %u, but "
2861                                      "this node has already received it!\n",
2862                                      dlm->name, fr->node_idx, fr->dead_node);
2863                                 dlm_print_reco_node_status(dlm);
2864                                 BUG();
2865                         }
2866                         dlm->reco.state |= DLM_RECO_STATE_FINALIZE;
2867                         spin_unlock(&dlm->spinlock);
2868                         break;
2869                 case 2:
2870                         if (!(dlm->reco.state & DLM_RECO_STATE_FINALIZE)) {
2871                                 mlog(ML_ERROR, "%s: received finalize2 from "
2872                                      "new master %u for dead node %u, but "
2873                                      "this node did not have finalize1!\n",
2874                                      dlm->name, fr->node_idx, fr->dead_node);
2875                                 dlm_print_reco_node_status(dlm);
2876                                 BUG();
2877                         }
2878                         dlm->reco.state &= ~DLM_RECO_STATE_FINALIZE;
2879                         spin_unlock(&dlm->spinlock);
2880                         dlm_reset_recovery(dlm);
2881                         dlm_kick_recovery_thread(dlm);
2882                         break;
2883                 default:
2884                         BUG();
2885         }
2886
2887         mlog(0, "%s: recovery done, reco master was %u, dead now %u, master now %u\n",
2888              dlm->name, fr->node_idx, dlm->reco.dead_node, dlm->reco.new_master);
2889
2890         dlm_put(dlm);
2891         return 0;
2892 }