linux/fs/ocfs2/dlm/dlmrecovery.c
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   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
  55static void dlm_do_local_recovery_cleanup(struct dlm_ctxt *dlm, u8 dead_node);
  56
  57static int dlm_recovery_thread(void *data);
  58static int dlm_do_recovery(struct dlm_ctxt *dlm);
  59
  60static int dlm_pick_recovery_master(struct dlm_ctxt *dlm);
  61static int dlm_remaster_locks(struct dlm_ctxt *dlm, u8 dead_node);
  62static int dlm_init_recovery_area(struct dlm_ctxt *dlm, u8 dead_node);
  63static int dlm_request_all_locks(struct dlm_ctxt *dlm,
  64                                 u8 request_from, u8 dead_node);
  65static void dlm_destroy_recovery_area(struct dlm_ctxt *dlm, u8 dead_node);
  66
  67static inline int dlm_num_locks_in_lockres(struct dlm_lock_resource *res);
  68static void dlm_init_migratable_lockres(struct dlm_migratable_lockres *mres,
  69                                        const char *lockname, int namelen,
  70                                        int total_locks, u64 cookie,
  71                                        u8 flags, u8 master);
  72static int dlm_send_mig_lockres_msg(struct dlm_ctxt *dlm,
  73                                    struct dlm_migratable_lockres *mres,
  74                                    u8 send_to,
  75                                    struct dlm_lock_resource *res,
  76                                    int total_locks);
  77static int dlm_process_recovery_data(struct dlm_ctxt *dlm,
  78                                     struct dlm_lock_resource *res,
  79                                     struct dlm_migratable_lockres *mres);
  80static int dlm_send_finalize_reco_message(struct dlm_ctxt *dlm);
  81static int dlm_send_all_done_msg(struct dlm_ctxt *dlm,
  82                                 u8 dead_node, u8 send_to);
  83static int dlm_send_begin_reco_message(struct dlm_ctxt *dlm, u8 dead_node);
  84static void dlm_move_reco_locks_to_list(struct dlm_ctxt *dlm,
  85                                        struct list_head *list, u8 dead_node);
  86static void dlm_finish_local_lockres_recovery(struct dlm_ctxt *dlm,
  87                                              u8 dead_node, u8 new_master);
  88static void dlm_reco_ast(void *astdata);
  89static void dlm_reco_bast(void *astdata, int blocked_type);
  90static void dlm_reco_unlock_ast(void *astdata, enum dlm_status st);
  91static void dlm_request_all_locks_worker(struct dlm_work_item *item,
  92                                         void *data);
  93static void dlm_mig_lockres_worker(struct dlm_work_item *item, void *data);
  94static int dlm_lockres_master_requery(struct dlm_ctxt *dlm,
  95                                      struct dlm_lock_resource *res,
  96                                      u8 *real_master);
  97
  98static u64 dlm_get_next_mig_cookie(void);
  99
 100static DEFINE_SPINLOCK(dlm_reco_state_lock);
 101static DEFINE_SPINLOCK(dlm_mig_cookie_lock);
 102static u64 dlm_mig_cookie = 1;
 103
 104static u64 dlm_get_next_mig_cookie(void)
 105{
 106        u64 c;
 107        spin_lock(&dlm_mig_cookie_lock);
 108        c = dlm_mig_cookie;
 109        if (dlm_mig_cookie == (~0ULL))
 110                dlm_mig_cookie = 1;
 111        else
 112                dlm_mig_cookie++;
 113        spin_unlock(&dlm_mig_cookie_lock);
 114        return c;
 115}
 116
 117static inline void dlm_set_reco_dead_node(struct dlm_ctxt *dlm,
 118                                          u8 dead_node)
 119{
 120        assert_spin_locked(&dlm->spinlock);
 121        if (dlm->reco.dead_node != dead_node)
 122                mlog(0, "%s: changing dead_node from %u to %u\n",
 123                     dlm->name, dlm->reco.dead_node, dead_node);
 124        dlm->reco.dead_node = dead_node;
 125}
 126
 127static inline void dlm_set_reco_master(struct dlm_ctxt *dlm,
 128                                       u8 master)
 129{
 130        assert_spin_locked(&dlm->spinlock);
 131        mlog(0, "%s: changing new_master from %u to %u\n",
 132             dlm->name, dlm->reco.new_master, master);
 133        dlm->reco.new_master = master;
 134}
 135
 136static inline void __dlm_reset_recovery(struct dlm_ctxt *dlm)
 137{
 138        assert_spin_locked(&dlm->spinlock);
 139        clear_bit(dlm->reco.dead_node, dlm->recovery_map);
 140        dlm_set_reco_dead_node(dlm, O2NM_INVALID_NODE_NUM);
 141        dlm_set_reco_master(dlm, O2NM_INVALID_NODE_NUM);
 142}
 143
 144static inline void dlm_reset_recovery(struct dlm_ctxt *dlm)
 145{
 146        spin_lock(&dlm->spinlock);
 147        __dlm_reset_recovery(dlm);
 148        spin_unlock(&dlm->spinlock);
 149}
 150
 151/* Worker function used during recovery. */
 152void dlm_dispatch_work(struct work_struct *work)
 153{
 154        struct dlm_ctxt *dlm =
 155                container_of(work, struct dlm_ctxt, dispatched_work);
 156        LIST_HEAD(tmp_list);
 157        struct dlm_work_item *item, *next;
 158        dlm_workfunc_t *workfunc;
 159        int tot=0;
 160
 161        spin_lock(&dlm->work_lock);
 162        list_splice_init(&dlm->work_list, &tmp_list);
 163        spin_unlock(&dlm->work_lock);
 164
 165        list_for_each_entry(item, &tmp_list, list) {
 166                tot++;
 167        }
 168        mlog(0, "%s: work thread has %d work items\n", dlm->name, tot);
 169
 170        list_for_each_entry_safe(item, next, &tmp_list, list) {
 171                workfunc = item->func;
 172                list_del_init(&item->list);
 173
 174                /* already have ref on dlm to avoid having
 175                 * it disappear.  just double-check. */
 176                BUG_ON(item->dlm != dlm);
 177
 178                /* this is allowed to sleep and
 179                 * call network stuff */
 180                workfunc(item, item->data);
 181
 182                dlm_put(dlm);
 183                kfree(item);
 184        }
 185}
 186
 187/*
 188 * RECOVERY THREAD
 189 */
 190
 191void dlm_kick_recovery_thread(struct dlm_ctxt *dlm)
 192{
 193        /* wake the recovery thread
 194         * this will wake the reco thread in one of three places
 195         * 1) sleeping with no recovery happening
 196         * 2) sleeping with recovery mastered elsewhere
 197         * 3) recovery mastered here, waiting on reco data */
 198
 199        wake_up(&dlm->dlm_reco_thread_wq);
 200}
 201
 202/* Launch the recovery thread */
 203int dlm_launch_recovery_thread(struct dlm_ctxt *dlm)
 204{
 205        mlog(0, "starting dlm recovery thread...\n");
 206
 207        dlm->dlm_reco_thread_task = kthread_run(dlm_recovery_thread, dlm,
 208                        "dlm_reco-%s", dlm->name);
 209        if (IS_ERR(dlm->dlm_reco_thread_task)) {
 210                mlog_errno(PTR_ERR(dlm->dlm_reco_thread_task));
 211                dlm->dlm_reco_thread_task = NULL;
 212                return -EINVAL;
 213        }
 214
 215        return 0;
 216}
 217
 218void dlm_complete_recovery_thread(struct dlm_ctxt *dlm)
 219{
 220        if (dlm->dlm_reco_thread_task) {
 221                mlog(0, "waiting for dlm recovery thread to exit\n");
 222                kthread_stop(dlm->dlm_reco_thread_task);
 223                dlm->dlm_reco_thread_task = NULL;
 224        }
 225}
 226
 227
 228
 229/*
 230 * this is lame, but here's how recovery works...
 231 * 1) all recovery threads cluster wide will work on recovering
 232 *    ONE node at a time
 233 * 2) negotiate who will take over all the locks for the dead node.
 234 *    thats right... ALL the locks.
 235 * 3) once a new master is chosen, everyone scans all locks
 236 *    and moves aside those mastered by the dead guy
 237 * 4) each of these locks should be locked until recovery is done
 238 * 5) the new master collects up all of secondary lock queue info
 239 *    one lock at a time, forcing each node to communicate back
 240 *    before continuing
 241 * 6) each secondary lock queue responds with the full known lock info
 242 * 7) once the new master has run all its locks, it sends a ALLDONE!
 243 *    message to everyone
 244 * 8) upon receiving this message, the secondary queue node unlocks
 245 *    and responds to the ALLDONE
 246 * 9) once the new master gets responses from everyone, he unlocks
 247 *    everything and recovery for this dead node is done
 248 *10) go back to 2) while there are still dead nodes
 249 *
 250 */
 251
 252static void dlm_print_reco_node_status(struct dlm_ctxt *dlm)
 253{
 254        struct dlm_reco_node_data *ndata;
 255        struct dlm_lock_resource *res;
 256
 257        mlog(ML_NOTICE, "%s(%d): recovery info, state=%s, dead=%u, master=%u\n",
 258             dlm->name, task_pid_nr(dlm->dlm_reco_thread_task),
 259             dlm->reco.state & DLM_RECO_STATE_ACTIVE ? "ACTIVE" : "inactive",
 260             dlm->reco.dead_node, dlm->reco.new_master);
 261
 262        list_for_each_entry(ndata, &dlm->reco.node_data, list) {
 263                char *st = "unknown";
 264                switch (ndata->state) {
 265                        case DLM_RECO_NODE_DATA_INIT:
 266                                st = "init";
 267                                break;
 268                        case DLM_RECO_NODE_DATA_REQUESTING:
 269                                st = "requesting";
 270                                break;
 271                        case DLM_RECO_NODE_DATA_DEAD:
 272                                st = "dead";
 273                                break;
 274                        case DLM_RECO_NODE_DATA_RECEIVING:
 275                                st = "receiving";
 276                                break;
 277                        case DLM_RECO_NODE_DATA_REQUESTED:
 278                                st = "requested";
 279                                break;
 280                        case DLM_RECO_NODE_DATA_DONE:
 281                                st = "done";
 282                                break;
 283                        case DLM_RECO_NODE_DATA_FINALIZE_SENT:
 284                                st = "finalize-sent";
 285                                break;
 286                        default:
 287                                st = "bad";
 288                                break;
 289                }
 290                mlog(ML_NOTICE, "%s: reco state, node %u, state=%s\n",
 291                     dlm->name, ndata->node_num, st);
 292        }
 293        list_for_each_entry(res, &dlm->reco.resources, recovering) {
 294                mlog(ML_NOTICE, "%s: lockres %.*s on recovering list\n",
 295                     dlm->name, res->lockname.len, res->lockname.name);
 296        }
 297}
 298
 299#define DLM_RECO_THREAD_TIMEOUT_MS (5 * 1000)
 300
 301static int dlm_recovery_thread(void *data)
 302{
 303        int status;
 304        struct dlm_ctxt *dlm = data;
 305        unsigned long timeout = msecs_to_jiffies(DLM_RECO_THREAD_TIMEOUT_MS);
 306
 307        mlog(0, "dlm thread running for %s...\n", dlm->name);
 308
 309        while (!kthread_should_stop()) {
 310                if (dlm_domain_fully_joined(dlm)) {
 311                        status = dlm_do_recovery(dlm);
 312                        if (status == -EAGAIN) {
 313                                /* do not sleep, recheck immediately. */
 314                                continue;
 315                        }
 316                        if (status < 0)
 317                                mlog_errno(status);
 318                }
 319
 320                wait_event_interruptible_timeout(dlm->dlm_reco_thread_wq,
 321                                                 kthread_should_stop(),
 322                                                 timeout);
 323        }
 324
 325        mlog(0, "quitting DLM recovery thread\n");
 326        return 0;
 327}
 328
 329/* returns true when the recovery master has contacted us */
 330static int dlm_reco_master_ready(struct dlm_ctxt *dlm)
 331{
 332        int ready;
 333        spin_lock(&dlm->spinlock);
 334        ready = (dlm->reco.new_master != O2NM_INVALID_NODE_NUM);
 335        spin_unlock(&dlm->spinlock);
 336        return ready;
 337}
 338
 339/* returns true if node is no longer in the domain
 340 * could be dead or just not joined */
 341int dlm_is_node_dead(struct dlm_ctxt *dlm, u8 node)
 342{
 343        int dead;
 344        spin_lock(&dlm->spinlock);
 345        dead = !test_bit(node, dlm->domain_map);
 346        spin_unlock(&dlm->spinlock);
 347        return dead;
 348}
 349
 350/* returns true if node is no longer in the domain
 351 * could be dead or just not joined */
 352static int dlm_is_node_recovered(struct dlm_ctxt *dlm, u8 node)
 353{
 354        int recovered;
 355        spin_lock(&dlm->spinlock);
 356        recovered = !test_bit(node, dlm->recovery_map);
 357        spin_unlock(&dlm->spinlock);
 358        return recovered;
 359}
 360
 361
 362void dlm_wait_for_node_death(struct dlm_ctxt *dlm, u8 node, int timeout)
 363{
 364        if (dlm_is_node_dead(dlm, node))
 365                return;
 366
 367        printk(KERN_NOTICE "o2dlm: Waiting on the death of node %u in "
 368               "domain %s\n", node, dlm->name);
 369
 370        if (timeout)
 371                wait_event_timeout(dlm->dlm_reco_thread_wq,
 372                                   dlm_is_node_dead(dlm, node),
 373                                   msecs_to_jiffies(timeout));
 374        else
 375                wait_event(dlm->dlm_reco_thread_wq,
 376                           dlm_is_node_dead(dlm, node));
 377}
 378
 379void dlm_wait_for_node_recovery(struct dlm_ctxt *dlm, u8 node, int timeout)
 380{
 381        if (dlm_is_node_recovered(dlm, node))
 382                return;
 383
 384        printk(KERN_NOTICE "o2dlm: Waiting on the recovery of node %u in "
 385               "domain %s\n", node, dlm->name);
 386
 387        if (timeout)
 388                wait_event_timeout(dlm->dlm_reco_thread_wq,
 389                                   dlm_is_node_recovered(dlm, node),
 390                                   msecs_to_jiffies(timeout));
 391        else
 392                wait_event(dlm->dlm_reco_thread_wq,
 393                           dlm_is_node_recovered(dlm, node));
 394}
 395
 396/* callers of the top-level api calls (dlmlock/dlmunlock) should
 397 * block on the dlm->reco.event when recovery is in progress.
 398 * the dlm recovery thread will set this state when it begins
 399 * recovering a dead node (as the new master or not) and clear
 400 * the state and wake as soon as all affected lock resources have
 401 * been marked with the RECOVERY flag */
 402static int dlm_in_recovery(struct dlm_ctxt *dlm)
 403{
 404        int in_recovery;
 405        spin_lock(&dlm->spinlock);
 406        in_recovery = !!(dlm->reco.state & DLM_RECO_STATE_ACTIVE);
 407        spin_unlock(&dlm->spinlock);
 408        return in_recovery;
 409}
 410
 411
 412void dlm_wait_for_recovery(struct dlm_ctxt *dlm)
 413{
 414        if (dlm_in_recovery(dlm)) {
 415                mlog(0, "%s: reco thread %d in recovery: "
 416                     "state=%d, master=%u, dead=%u\n",
 417                     dlm->name, task_pid_nr(dlm->dlm_reco_thread_task),
 418                     dlm->reco.state, dlm->reco.new_master,
 419                     dlm->reco.dead_node);
 420        }
 421        wait_event(dlm->reco.event, !dlm_in_recovery(dlm));
 422}
 423
 424static void dlm_begin_recovery(struct dlm_ctxt *dlm)
 425{
 426        spin_lock(&dlm->spinlock);
 427        BUG_ON(dlm->reco.state & DLM_RECO_STATE_ACTIVE);
 428        printk(KERN_NOTICE "o2dlm: Begin recovery on domain %s for node %u\n",
 429               dlm->name, dlm->reco.dead_node);
 430        dlm->reco.state |= DLM_RECO_STATE_ACTIVE;
 431        spin_unlock(&dlm->spinlock);
 432}
 433
 434static void dlm_end_recovery(struct dlm_ctxt *dlm)
 435{
 436        spin_lock(&dlm->spinlock);
 437        BUG_ON(!(dlm->reco.state & DLM_RECO_STATE_ACTIVE));
 438        dlm->reco.state &= ~DLM_RECO_STATE_ACTIVE;
 439        spin_unlock(&dlm->spinlock);
 440        printk(KERN_NOTICE "o2dlm: End recovery on domain %s\n", dlm->name);
 441        wake_up(&dlm->reco.event);
 442}
 443
 444static void dlm_print_recovery_master(struct dlm_ctxt *dlm)
 445{
 446        printk(KERN_NOTICE "o2dlm: Node %u (%s) is the Recovery Master for the "
 447               "dead node %u in domain %s\n", dlm->reco.new_master,
 448               (dlm->node_num == dlm->reco.new_master ? "me" : "he"),
 449               dlm->reco.dead_node, dlm->name);
 450}
 451
 452static int dlm_do_recovery(struct dlm_ctxt *dlm)
 453{
 454        int status = 0;
 455        int ret;
 456
 457        spin_lock(&dlm->spinlock);
 458
 459        /* check to see if the new master has died */
 460        if (dlm->reco.new_master != O2NM_INVALID_NODE_NUM &&
 461            test_bit(dlm->reco.new_master, dlm->recovery_map)) {
 462                mlog(0, "new master %u died while recovering %u!\n",
 463                     dlm->reco.new_master, dlm->reco.dead_node);
 464                /* unset the new_master, leave dead_node */
 465                dlm_set_reco_master(dlm, O2NM_INVALID_NODE_NUM);
 466        }
 467
 468        /* select a target to recover */
 469        if (dlm->reco.dead_node == O2NM_INVALID_NODE_NUM) {
 470                int bit;
 471
 472                bit = find_next_bit (dlm->recovery_map, O2NM_MAX_NODES, 0);
 473                if (bit >= O2NM_MAX_NODES || bit < 0)
 474                        dlm_set_reco_dead_node(dlm, O2NM_INVALID_NODE_NUM);
 475                else
 476                        dlm_set_reco_dead_node(dlm, bit);
 477        } else if (!test_bit(dlm->reco.dead_node, dlm->recovery_map)) {
 478                /* BUG? */
 479                mlog(ML_ERROR, "dead_node %u no longer in recovery map!\n",
 480                     dlm->reco.dead_node);
 481                dlm_set_reco_dead_node(dlm, O2NM_INVALID_NODE_NUM);
 482        }
 483
 484        if (dlm->reco.dead_node == O2NM_INVALID_NODE_NUM) {
 485                // mlog(0, "nothing to recover!  sleeping now!\n");
 486                spin_unlock(&dlm->spinlock);
 487                /* return to main thread loop and sleep. */
 488                return 0;
 489        }
 490        mlog(0, "%s(%d):recovery thread found node %u in the recovery map!\n",
 491             dlm->name, task_pid_nr(dlm->dlm_reco_thread_task),
 492             dlm->reco.dead_node);
 493        spin_unlock(&dlm->spinlock);
 494
 495        /* take write barrier */
 496        /* (stops the list reshuffling thread, proxy ast handling) */
 497        dlm_begin_recovery(dlm);
 498
 499        if (dlm->reco.new_master == dlm->node_num)
 500                goto master_here;
 501
 502        if (dlm->reco.new_master == O2NM_INVALID_NODE_NUM) {
 503                /* choose a new master, returns 0 if this node
 504                 * is the master, -EEXIST if it's another node.
 505                 * this does not return until a new master is chosen
 506                 * or recovery completes entirely. */
 507                ret = dlm_pick_recovery_master(dlm);
 508                if (!ret) {
 509                        /* already notified everyone.  go. */
 510                        goto master_here;
 511                }
 512                mlog(0, "another node will master this recovery session.\n");
 513        }
 514
 515        dlm_print_recovery_master(dlm);
 516
 517        /* it is safe to start everything back up here
 518         * because all of the dead node's lock resources
 519         * have been marked as in-recovery */
 520        dlm_end_recovery(dlm);
 521
 522        /* sleep out in main dlm_recovery_thread loop. */
 523        return 0;
 524
 525master_here:
 526        dlm_print_recovery_master(dlm);
 527
 528        status = dlm_remaster_locks(dlm, dlm->reco.dead_node);
 529        if (status < 0) {
 530                /* we should never hit this anymore */
 531                mlog(ML_ERROR, "%s: Error %d remastering locks for node %u, "
 532                     "retrying.\n", dlm->name, status, dlm->reco.dead_node);
 533                /* yield a bit to allow any final network messages
 534                 * to get handled on remaining nodes */
 535                msleep(100);
 536        } else {
 537                /* success!  see if any other nodes need recovery */
 538                mlog(0, "DONE mastering recovery of %s:%u here(this=%u)!\n",
 539                     dlm->name, dlm->reco.dead_node, dlm->node_num);
 540                spin_lock(&dlm->spinlock);
 541                __dlm_reset_recovery(dlm);
 542                dlm->reco.state &= ~DLM_RECO_STATE_FINALIZE;
 543                spin_unlock(&dlm->spinlock);
 544        }
 545        dlm_end_recovery(dlm);
 546
 547        /* continue and look for another dead node */
 548        return -EAGAIN;
 549}
 550
 551static int dlm_remaster_locks(struct dlm_ctxt *dlm, u8 dead_node)
 552{
 553        int status = 0;
 554        struct dlm_reco_node_data *ndata;
 555        int all_nodes_done;
 556        int destroy = 0;
 557        int pass = 0;
 558
 559        do {
 560                /* we have become recovery master.  there is no escaping
 561                 * this, so just keep trying until we get it. */
 562                status = dlm_init_recovery_area(dlm, dead_node);
 563                if (status < 0) {
 564                        mlog(ML_ERROR, "%s: failed to alloc recovery area, "
 565                             "retrying\n", dlm->name);
 566                        msleep(1000);
 567                }
 568        } while (status != 0);
 569
 570        /* safe to access the node data list without a lock, since this
 571         * process is the only one to change the list */
 572        list_for_each_entry(ndata, &dlm->reco.node_data, list) {
 573                BUG_ON(ndata->state != DLM_RECO_NODE_DATA_INIT);
 574                ndata->state = DLM_RECO_NODE_DATA_REQUESTING;
 575
 576                mlog(0, "%s: Requesting lock info from node %u\n", dlm->name,
 577                     ndata->node_num);
 578
 579                if (ndata->node_num == dlm->node_num) {
 580                        ndata->state = DLM_RECO_NODE_DATA_DONE;
 581                        continue;
 582                }
 583
 584                do {
 585                        status = dlm_request_all_locks(dlm, ndata->node_num,
 586                                                       dead_node);
 587                        if (status < 0) {
 588                                mlog_errno(status);
 589                                if (dlm_is_host_down(status)) {
 590                                        /* node died, ignore it for recovery */
 591                                        status = 0;
 592                                        ndata->state = DLM_RECO_NODE_DATA_DEAD;
 593                                        /* wait for the domain map to catch up
 594                                         * with the network state. */
 595                                        wait_event_timeout(dlm->dlm_reco_thread_wq,
 596                                                           dlm_is_node_dead(dlm,
 597                                                                ndata->node_num),
 598                                                           msecs_to_jiffies(1000));
 599                                        mlog(0, "waited 1 sec for %u, "
 600                                             "dead? %s\n", ndata->node_num,
 601                                             dlm_is_node_dead(dlm, ndata->node_num) ?
 602                                             "yes" : "no");
 603                                } else {
 604                                        /* -ENOMEM on the other node */
 605                                        mlog(0, "%s: node %u returned "
 606                                             "%d during recovery, retrying "
 607                                             "after a short wait\n",
 608                                             dlm->name, ndata->node_num,
 609                                             status);
 610                                        msleep(100);
 611                                }
 612                        }
 613                } while (status != 0);
 614
 615                spin_lock(&dlm_reco_state_lock);
 616                switch (ndata->state) {
 617                        case DLM_RECO_NODE_DATA_INIT:
 618                        case DLM_RECO_NODE_DATA_FINALIZE_SENT:
 619                        case DLM_RECO_NODE_DATA_REQUESTED:
 620                                BUG();
 621                                break;
 622                        case DLM_RECO_NODE_DATA_DEAD:
 623                                mlog(0, "node %u died after requesting "
 624                                     "recovery info for node %u\n",
 625                                     ndata->node_num, dead_node);
 626                                /* fine.  don't need this node's info.
 627                                 * continue without it. */
 628                                break;
 629                        case DLM_RECO_NODE_DATA_REQUESTING:
 630                                ndata->state = DLM_RECO_NODE_DATA_REQUESTED;
 631                                mlog(0, "now receiving recovery data from "
 632                                     "node %u for dead node %u\n",
 633                                     ndata->node_num, dead_node);
 634                                break;
 635                        case DLM_RECO_NODE_DATA_RECEIVING:
 636                                mlog(0, "already receiving recovery data from "
 637                                     "node %u for dead node %u\n",
 638                                     ndata->node_num, dead_node);
 639                                break;
 640                        case DLM_RECO_NODE_DATA_DONE:
 641                                mlog(0, "already DONE receiving recovery data "
 642                                     "from node %u for dead node %u\n",
 643                                     ndata->node_num, dead_node);
 644                                break;
 645                }
 646                spin_unlock(&dlm_reco_state_lock);
 647        }
 648
 649        mlog(0, "%s: Done requesting all lock info\n", dlm->name);
 650
 651        /* nodes should be sending reco data now
 652         * just need to wait */
 653
 654        while (1) {
 655                /* check all the nodes now to see if we are
 656                 * done, or if anyone died */
 657                all_nodes_done = 1;
 658                spin_lock(&dlm_reco_state_lock);
 659                list_for_each_entry(ndata, &dlm->reco.node_data, list) {
 660                        mlog(0, "checking recovery state of node %u\n",
 661                             ndata->node_num);
 662                        switch (ndata->state) {
 663                                case DLM_RECO_NODE_DATA_INIT:
 664                                case DLM_RECO_NODE_DATA_REQUESTING:
 665                                        mlog(ML_ERROR, "bad ndata state for "
 666                                             "node %u: state=%d\n",
 667                                             ndata->node_num, ndata->state);
 668                                        BUG();
 669                                        break;
 670                                case DLM_RECO_NODE_DATA_DEAD:
 671                                        mlog(0, "node %u died after "
 672                                             "requesting recovery info for "
 673                                             "node %u\n", ndata->node_num,
 674                                             dead_node);
 675                                        break;
 676                                case DLM_RECO_NODE_DATA_RECEIVING:
 677                                case DLM_RECO_NODE_DATA_REQUESTED:
 678                                        mlog(0, "%s: node %u still in state %s\n",
 679                                             dlm->name, ndata->node_num,
 680                                             ndata->state==DLM_RECO_NODE_DATA_RECEIVING ?
 681                                             "receiving" : "requested");
 682                                        all_nodes_done = 0;
 683                                        break;
 684                                case DLM_RECO_NODE_DATA_DONE:
 685                                        mlog(0, "%s: node %u state is done\n",
 686                                             dlm->name, ndata->node_num);
 687                                        break;
 688                                case DLM_RECO_NODE_DATA_FINALIZE_SENT:
 689                                        mlog(0, "%s: node %u state is finalize\n",
 690                                             dlm->name, ndata->node_num);
 691                                        break;
 692                        }
 693                }
 694                spin_unlock(&dlm_reco_state_lock);
 695
 696                mlog(0, "pass #%d, all_nodes_done?: %s\n", ++pass,
 697                     all_nodes_done?"yes":"no");
 698                if (all_nodes_done) {
 699                        int ret;
 700
 701                        /* Set this flag on recovery master to avoid
 702                         * a new recovery for another dead node start
 703                         * before the recovery is not done. That may
 704                         * cause recovery hung.*/
 705                        spin_lock(&dlm->spinlock);
 706                        dlm->reco.state |= DLM_RECO_STATE_FINALIZE;
 707                        spin_unlock(&dlm->spinlock);
 708
 709                        /* all nodes are now in DLM_RECO_NODE_DATA_DONE state
 710                         * just send a finalize message to everyone and
 711                         * clean up */
 712                        mlog(0, "all nodes are done! send finalize\n");
 713                        ret = dlm_send_finalize_reco_message(dlm);
 714                        if (ret < 0)
 715                                mlog_errno(ret);
 716
 717                        spin_lock(&dlm->spinlock);
 718                        dlm_finish_local_lockres_recovery(dlm, dead_node,
 719                                                          dlm->node_num);
 720                        spin_unlock(&dlm->spinlock);
 721                        mlog(0, "should be done with recovery!\n");
 722
 723                        mlog(0, "finishing recovery of %s at %lu, "
 724                             "dead=%u, this=%u, new=%u\n", dlm->name,
 725                             jiffies, dlm->reco.dead_node,
 726                             dlm->node_num, dlm->reco.new_master);
 727                        destroy = 1;
 728                        status = 0;
 729                        /* rescan everything marked dirty along the way */
 730                        dlm_kick_thread(dlm, NULL);
 731                        break;
 732                }
 733                /* wait to be signalled, with periodic timeout
 734                 * to check for node death */
 735                wait_event_interruptible_timeout(dlm->dlm_reco_thread_wq,
 736                                         kthread_should_stop(),
 737                                         msecs_to_jiffies(DLM_RECO_THREAD_TIMEOUT_MS));
 738
 739        }
 740
 741        if (destroy)
 742                dlm_destroy_recovery_area(dlm, dead_node);
 743
 744        return status;
 745}
 746
 747static int dlm_init_recovery_area(struct dlm_ctxt *dlm, u8 dead_node)
 748{
 749        int num=0;
 750        struct dlm_reco_node_data *ndata;
 751
 752        spin_lock(&dlm->spinlock);
 753        memcpy(dlm->reco.node_map, dlm->domain_map, sizeof(dlm->domain_map));
 754        /* nodes can only be removed (by dying) after dropping
 755         * this lock, and death will be trapped later, so this should do */
 756        spin_unlock(&dlm->spinlock);
 757
 758        while (1) {
 759                num = find_next_bit (dlm->reco.node_map, O2NM_MAX_NODES, num);
 760                if (num >= O2NM_MAX_NODES) {
 761                        break;
 762                }
 763                BUG_ON(num == dead_node);
 764
 765                ndata = kzalloc(sizeof(*ndata), GFP_NOFS);
 766                if (!ndata) {
 767                        dlm_destroy_recovery_area(dlm, dead_node);
 768                        return -ENOMEM;
 769                }
 770                ndata->node_num = num;
 771                ndata->state = DLM_RECO_NODE_DATA_INIT;
 772                spin_lock(&dlm_reco_state_lock);
 773                list_add_tail(&ndata->list, &dlm->reco.node_data);
 774                spin_unlock(&dlm_reco_state_lock);
 775                num++;
 776        }
 777
 778        return 0;
 779}
 780
 781static void dlm_destroy_recovery_area(struct dlm_ctxt *dlm, u8 dead_node)
 782{
 783        struct dlm_reco_node_data *ndata, *next;
 784        LIST_HEAD(tmplist);
 785
 786        spin_lock(&dlm_reco_state_lock);
 787        list_splice_init(&dlm->reco.node_data, &tmplist);
 788        spin_unlock(&dlm_reco_state_lock);
 789
 790        list_for_each_entry_safe(ndata, next, &tmplist, list) {
 791                list_del_init(&ndata->list);
 792                kfree(ndata);
 793        }
 794}
 795
 796static int dlm_request_all_locks(struct dlm_ctxt *dlm, u8 request_from,
 797                                 u8 dead_node)
 798{
 799        struct dlm_lock_request lr;
 800        int ret;
 801        int status;
 802
 803        mlog(0, "\n");
 804
 805
 806        mlog(0, "dlm_request_all_locks: dead node is %u, sending request "
 807                  "to %u\n", dead_node, request_from);
 808
 809        memset(&lr, 0, sizeof(lr));
 810        lr.node_idx = dlm->node_num;
 811        lr.dead_node = dead_node;
 812
 813        // send message
 814        ret = o2net_send_message(DLM_LOCK_REQUEST_MSG, dlm->key,
 815                                 &lr, sizeof(lr), request_from, &status);
 816
 817        /* negative status is handled by caller */
 818        if (ret < 0)
 819                mlog(ML_ERROR, "%s: Error %d send LOCK_REQUEST to node %u "
 820                     "to recover dead node %u\n", dlm->name, ret,
 821                     request_from, dead_node);
 822        else
 823                ret = status;
 824        // return from here, then
 825        // sleep until all received or error
 826        return ret;
 827
 828}
 829
 830int dlm_request_all_locks_handler(struct o2net_msg *msg, u32 len, void *data,
 831                                  void **ret_data)
 832{
 833        struct dlm_ctxt *dlm = data;
 834        struct dlm_lock_request *lr = (struct dlm_lock_request *)msg->buf;
 835        char *buf = NULL;
 836        struct dlm_work_item *item = NULL;
 837
 838        if (!dlm_grab(dlm))
 839                return -EINVAL;
 840
 841        if (lr->dead_node != dlm->reco.dead_node) {
 842                mlog(ML_ERROR, "%s: node %u sent dead_node=%u, but local "
 843                     "dead_node is %u\n", dlm->name, lr->node_idx,
 844                     lr->dead_node, dlm->reco.dead_node);
 845                dlm_print_reco_node_status(dlm);
 846                /* this is a hack */
 847                dlm_put(dlm);
 848                return -ENOMEM;
 849        }
 850        BUG_ON(lr->dead_node != dlm->reco.dead_node);
 851
 852        item = kzalloc(sizeof(*item), GFP_NOFS);
 853        if (!item) {
 854                dlm_put(dlm);
 855                return -ENOMEM;
 856        }
 857
 858        /* this will get freed by dlm_request_all_locks_worker */
 859        buf = (char *) __get_free_page(GFP_NOFS);
 860        if (!buf) {
 861                kfree(item);
 862                dlm_put(dlm);
 863                return -ENOMEM;
 864        }
 865
 866        /* queue up work for dlm_request_all_locks_worker */
 867        dlm_grab(dlm);  /* get an extra ref for the work item */
 868        dlm_init_work_item(dlm, item, dlm_request_all_locks_worker, buf);
 869        item->u.ral.reco_master = lr->node_idx;
 870        item->u.ral.dead_node = lr->dead_node;
 871        spin_lock(&dlm->work_lock);
 872        list_add_tail(&item->list, &dlm->work_list);
 873        spin_unlock(&dlm->work_lock);
 874        queue_work(dlm->dlm_worker, &dlm->dispatched_work);
 875
 876        dlm_put(dlm);
 877        return 0;
 878}
 879
 880static void dlm_request_all_locks_worker(struct dlm_work_item *item, void *data)
 881{
 882        struct dlm_migratable_lockres *mres;
 883        struct dlm_lock_resource *res;
 884        struct dlm_ctxt *dlm;
 885        LIST_HEAD(resources);
 886        int ret;
 887        u8 dead_node, reco_master;
 888        int skip_all_done = 0;
 889
 890        dlm = item->dlm;
 891        dead_node = item->u.ral.dead_node;
 892        reco_master = item->u.ral.reco_master;
 893        mres = (struct dlm_migratable_lockres *)data;
 894
 895        mlog(0, "%s: recovery worker started, dead=%u, master=%u\n",
 896             dlm->name, dead_node, reco_master);
 897
 898        if (dead_node != dlm->reco.dead_node ||
 899            reco_master != dlm->reco.new_master) {
 900                /* worker could have been created before the recovery master
 901                 * died.  if so, do not continue, but do not error. */
 902                if (dlm->reco.new_master == O2NM_INVALID_NODE_NUM) {
 903                        mlog(ML_NOTICE, "%s: will not send recovery state, "
 904                             "recovery master %u died, thread=(dead=%u,mas=%u)"
 905                             " current=(dead=%u,mas=%u)\n", dlm->name,
 906                             reco_master, dead_node, reco_master,
 907                             dlm->reco.dead_node, dlm->reco.new_master);
 908                } else {
 909                        mlog(ML_NOTICE, "%s: reco state invalid: reco(dead=%u, "
 910                             "master=%u), request(dead=%u, master=%u)\n",
 911                             dlm->name, dlm->reco.dead_node,
 912                             dlm->reco.new_master, dead_node, reco_master);
 913                }
 914                goto leave;
 915        }
 916
 917        /* lock resources should have already been moved to the
 918         * dlm->reco.resources list.  now move items from that list
 919         * to a temp list if the dead owner matches.  note that the
 920         * whole cluster recovers only one node at a time, so we
 921         * can safely move UNKNOWN lock resources for each recovery
 922         * session. */
 923        dlm_move_reco_locks_to_list(dlm, &resources, dead_node);
 924
 925        /* now we can begin blasting lockreses without the dlm lock */
 926
 927        /* any errors returned will be due to the new_master dying,
 928         * the dlm_reco_thread should detect this */
 929        list_for_each_entry(res, &resources, recovering) {
 930                ret = dlm_send_one_lockres(dlm, res, mres, reco_master,
 931                                        DLM_MRES_RECOVERY);
 932                if (ret < 0) {
 933                        mlog(ML_ERROR, "%s: node %u went down while sending "
 934                             "recovery state for dead node %u, ret=%d\n", dlm->name,
 935                             reco_master, dead_node, ret);
 936                        skip_all_done = 1;
 937                        break;
 938                }
 939        }
 940
 941        /* move the resources back to the list */
 942        spin_lock(&dlm->spinlock);
 943        list_splice_init(&resources, &dlm->reco.resources);
 944        spin_unlock(&dlm->spinlock);
 945
 946        if (!skip_all_done) {
 947                ret = dlm_send_all_done_msg(dlm, dead_node, reco_master);
 948                if (ret < 0) {
 949                        mlog(ML_ERROR, "%s: node %u went down while sending "
 950                             "recovery all-done for dead node %u, ret=%d\n",
 951                             dlm->name, reco_master, dead_node, ret);
 952                }
 953        }
 954leave:
 955        free_page((unsigned long)data);
 956}
 957
 958
 959static int dlm_send_all_done_msg(struct dlm_ctxt *dlm, u8 dead_node, u8 send_to)
 960{
 961        int ret, tmpret;
 962        struct dlm_reco_data_done done_msg;
 963
 964        memset(&done_msg, 0, sizeof(done_msg));
 965        done_msg.node_idx = dlm->node_num;
 966        done_msg.dead_node = dead_node;
 967        mlog(0, "sending DATA DONE message to %u, "
 968             "my node=%u, dead node=%u\n", send_to, done_msg.node_idx,
 969             done_msg.dead_node);
 970
 971        ret = o2net_send_message(DLM_RECO_DATA_DONE_MSG, dlm->key, &done_msg,
 972                                 sizeof(done_msg), send_to, &tmpret);
 973        if (ret < 0) {
 974                mlog(ML_ERROR, "%s: Error %d send RECO_DATA_DONE to node %u "
 975                     "to recover dead node %u\n", dlm->name, ret, send_to,
 976                     dead_node);
 977                if (!dlm_is_host_down(ret)) {
 978                        BUG();
 979                }
 980        } else
 981                ret = tmpret;
 982        return ret;
 983}
 984
 985
 986int dlm_reco_data_done_handler(struct o2net_msg *msg, u32 len, void *data,
 987                               void **ret_data)
 988{
 989        struct dlm_ctxt *dlm = data;
 990        struct dlm_reco_data_done *done = (struct dlm_reco_data_done *)msg->buf;
 991        struct dlm_reco_node_data *ndata = NULL;
 992        int ret = -EINVAL;
 993
 994        if (!dlm_grab(dlm))
 995                return -EINVAL;
 996
 997        mlog(0, "got DATA DONE: dead_node=%u, reco.dead_node=%u, "
 998             "node_idx=%u, this node=%u\n", done->dead_node,
 999             dlm->reco.dead_node, done->node_idx, dlm->node_num);
1000
1001        mlog_bug_on_msg((done->dead_node != dlm->reco.dead_node),
1002                        "Got DATA DONE: dead_node=%u, reco.dead_node=%u, "
1003                        "node_idx=%u, this node=%u\n", done->dead_node,
1004                        dlm->reco.dead_node, done->node_idx, dlm->node_num);
1005
1006        spin_lock(&dlm_reco_state_lock);
1007        list_for_each_entry(ndata, &dlm->reco.node_data, list) {
1008                if (ndata->node_num != done->node_idx)
1009                        continue;
1010
1011                switch (ndata->state) {
1012                        /* should have moved beyond INIT but not to FINALIZE yet */
1013                        case DLM_RECO_NODE_DATA_INIT:
1014                        case DLM_RECO_NODE_DATA_DEAD:
1015                        case DLM_RECO_NODE_DATA_FINALIZE_SENT:
1016                                mlog(ML_ERROR, "bad ndata state for node %u:"
1017                                     " state=%d\n", ndata->node_num,
1018                                     ndata->state);
1019                                BUG();
1020                                break;
1021                        /* these states are possible at this point, anywhere along
1022                         * the line of recovery */
1023                        case DLM_RECO_NODE_DATA_DONE:
1024                        case DLM_RECO_NODE_DATA_RECEIVING:
1025                        case DLM_RECO_NODE_DATA_REQUESTED:
1026                        case DLM_RECO_NODE_DATA_REQUESTING:
1027                                mlog(0, "node %u is DONE sending "
1028                                          "recovery data!\n",
1029                                          ndata->node_num);
1030
1031                                ndata->state = DLM_RECO_NODE_DATA_DONE;
1032                                ret = 0;
1033                                break;
1034                }
1035        }
1036        spin_unlock(&dlm_reco_state_lock);
1037
1038        /* wake the recovery thread, some node is done */
1039        if (!ret)
1040                dlm_kick_recovery_thread(dlm);
1041
1042        if (ret < 0)
1043                mlog(ML_ERROR, "failed to find recovery node data for node "
1044                     "%u\n", done->node_idx);
1045        dlm_put(dlm);
1046
1047        mlog(0, "leaving reco data done handler, ret=%d\n", ret);
1048        return ret;
1049}
1050
1051static void dlm_move_reco_locks_to_list(struct dlm_ctxt *dlm,
1052                                        struct list_head *list,
1053                                        u8 dead_node)
1054{
1055        struct dlm_lock_resource *res, *next;
1056        struct dlm_lock *lock;
1057
1058        spin_lock(&dlm->spinlock);
1059        list_for_each_entry_safe(res, next, &dlm->reco.resources, recovering) {
1060                /* always prune any $RECOVERY entries for dead nodes,
1061                 * otherwise hangs can occur during later recovery */
1062                if (dlm_is_recovery_lock(res->lockname.name,
1063                                         res->lockname.len)) {
1064                        spin_lock(&res->spinlock);
1065                        list_for_each_entry(lock, &res->granted, list) {
1066                                if (lock->ml.node == dead_node) {
1067                                        mlog(0, "AHA! there was "
1068                                             "a $RECOVERY lock for dead "
1069                                             "node %u (%s)!\n",
1070                                             dead_node, dlm->name);
1071                                        list_del_init(&lock->list);
1072                                        dlm_lock_put(lock);
1073                                        /* Can't schedule DLM_UNLOCK_FREE_LOCK
1074                                         * - do manually */
1075                                        dlm_lock_put(lock);
1076                                        break;
1077                                }
1078                        }
1079                        spin_unlock(&res->spinlock);
1080                        continue;
1081                }
1082
1083                if (res->owner == dead_node) {
1084                        mlog(0, "found lockres owned by dead node while "
1085                                  "doing recovery for node %u. sending it.\n",
1086                                  dead_node);
1087                        list_move_tail(&res->recovering, list);
1088                } else if (res->owner == DLM_LOCK_RES_OWNER_UNKNOWN) {
1089                        mlog(0, "found UNKNOWN owner while doing recovery "
1090                                  "for node %u. sending it.\n", dead_node);
1091                        list_move_tail(&res->recovering, list);
1092                }
1093        }
1094        spin_unlock(&dlm->spinlock);
1095}
1096
1097static inline int dlm_num_locks_in_lockres(struct dlm_lock_resource *res)
1098{
1099        int total_locks = 0;
1100        struct list_head *iter, *queue = &res->granted;
1101        int i;
1102
1103        for (i=0; i<3; i++) {
1104                list_for_each(iter, queue)
1105                        total_locks++;
1106                queue++;
1107        }
1108        return total_locks;
1109}
1110
1111
1112static int dlm_send_mig_lockres_msg(struct dlm_ctxt *dlm,
1113                                      struct dlm_migratable_lockres *mres,
1114                                      u8 send_to,
1115                                      struct dlm_lock_resource *res,
1116                                      int total_locks)
1117{
1118        u64 mig_cookie = be64_to_cpu(mres->mig_cookie);
1119        int mres_total_locks = be32_to_cpu(mres->total_locks);
1120        int sz, ret = 0, status = 0;
1121        u8 orig_flags = mres->flags,
1122           orig_master = mres->master;
1123
1124        BUG_ON(mres->num_locks > DLM_MAX_MIGRATABLE_LOCKS);
1125        if (!mres->num_locks)
1126                return 0;
1127
1128        sz = sizeof(struct dlm_migratable_lockres) +
1129                (mres->num_locks * sizeof(struct dlm_migratable_lock));
1130
1131        /* add an all-done flag if we reached the last lock */
1132        orig_flags = mres->flags;
1133        BUG_ON(total_locks > mres_total_locks);
1134        if (total_locks == mres_total_locks)
1135                mres->flags |= DLM_MRES_ALL_DONE;
1136
1137        mlog(0, "%s:%.*s: sending mig lockres (%s) to %u\n",
1138             dlm->name, res->lockname.len, res->lockname.name,
1139             orig_flags & DLM_MRES_MIGRATION ? "migration" : "recovery",
1140             send_to);
1141
1142        /* send it */
1143        ret = o2net_send_message(DLM_MIG_LOCKRES_MSG, dlm->key, mres,
1144                                 sz, send_to, &status);
1145        if (ret < 0) {
1146                /* XXX: negative status is not handled.
1147                 * this will end up killing this node. */
1148                mlog(ML_ERROR, "%s: res %.*s, Error %d send MIG_LOCKRES to "
1149                     "node %u (%s)\n", dlm->name, mres->lockname_len,
1150                     mres->lockname, ret, send_to,
1151                     (orig_flags & DLM_MRES_MIGRATION ?
1152                      "migration" : "recovery"));
1153        } else {
1154                /* might get an -ENOMEM back here */
1155                ret = status;
1156                if (ret < 0) {
1157                        mlog_errno(ret);
1158
1159                        if (ret == -EFAULT) {
1160                                mlog(ML_ERROR, "node %u told me to kill "
1161                                     "myself!\n", send_to);
1162                                BUG();
1163                        }
1164                }
1165        }
1166
1167        /* zero and reinit the message buffer */
1168        dlm_init_migratable_lockres(mres, res->lockname.name,
1169                                    res->lockname.len, mres_total_locks,
1170                                    mig_cookie, orig_flags, orig_master);
1171        return ret;
1172}
1173
1174static void dlm_init_migratable_lockres(struct dlm_migratable_lockres *mres,
1175                                        const char *lockname, int namelen,
1176                                        int total_locks, u64 cookie,
1177                                        u8 flags, u8 master)
1178{
1179        /* mres here is one full page */
1180        clear_page(mres);
1181        mres->lockname_len = namelen;
1182        memcpy(mres->lockname, lockname, namelen);
1183        mres->num_locks = 0;
1184        mres->total_locks = cpu_to_be32(total_locks);
1185        mres->mig_cookie = cpu_to_be64(cookie);
1186        mres->flags = flags;
1187        mres->master = master;
1188}
1189
1190static void dlm_prepare_lvb_for_migration(struct dlm_lock *lock,
1191                                          struct dlm_migratable_lockres *mres,
1192                                          int queue)
1193{
1194        if (!lock->lksb)
1195               return;
1196
1197        /* Ignore lvb in all locks in the blocked list */
1198        if (queue == DLM_BLOCKED_LIST)
1199                return;
1200
1201        /* Only consider lvbs in locks with granted EX or PR lock levels */
1202        if (lock->ml.type != LKM_EXMODE && lock->ml.type != LKM_PRMODE)
1203                return;
1204
1205        if (dlm_lvb_is_empty(mres->lvb)) {
1206                memcpy(mres->lvb, lock->lksb->lvb, DLM_LVB_LEN);
1207                return;
1208        }
1209
1210        /* Ensure the lvb copied for migration matches in other valid locks */
1211        if (!memcmp(mres->lvb, lock->lksb->lvb, DLM_LVB_LEN))
1212                return;
1213
1214        mlog(ML_ERROR, "Mismatched lvb in lock cookie=%u:%llu, name=%.*s, "
1215             "node=%u\n",
1216             dlm_get_lock_cookie_node(be64_to_cpu(lock->ml.cookie)),
1217             dlm_get_lock_cookie_seq(be64_to_cpu(lock->ml.cookie)),
1218             lock->lockres->lockname.len, lock->lockres->lockname.name,
1219             lock->ml.node);
1220        dlm_print_one_lock_resource(lock->lockres);
1221        BUG();
1222}
1223
1224/* returns 1 if this lock fills the network structure,
1225 * 0 otherwise */
1226static int dlm_add_lock_to_array(struct dlm_lock *lock,
1227                                 struct dlm_migratable_lockres *mres, int queue)
1228{
1229        struct dlm_migratable_lock *ml;
1230        int lock_num = mres->num_locks;
1231
1232        ml = &(mres->ml[lock_num]);
1233        ml->cookie = lock->ml.cookie;
1234        ml->type = lock->ml.type;
1235        ml->convert_type = lock->ml.convert_type;
1236        ml->highest_blocked = lock->ml.highest_blocked;
1237        ml->list = queue;
1238        if (lock->lksb) {
1239                ml->flags = lock->lksb->flags;
1240                dlm_prepare_lvb_for_migration(lock, mres, queue);
1241        }
1242        ml->node = lock->ml.node;
1243        mres->num_locks++;
1244        /* we reached the max, send this network message */
1245        if (mres->num_locks == DLM_MAX_MIGRATABLE_LOCKS)
1246                return 1;
1247        return 0;
1248}
1249
1250static void dlm_add_dummy_lock(struct dlm_ctxt *dlm,
1251                               struct dlm_migratable_lockres *mres)
1252{
1253        struct dlm_lock dummy;
1254        memset(&dummy, 0, sizeof(dummy));
1255        dummy.ml.cookie = 0;
1256        dummy.ml.type = LKM_IVMODE;
1257        dummy.ml.convert_type = LKM_IVMODE;
1258        dummy.ml.highest_blocked = LKM_IVMODE;
1259        dummy.lksb = NULL;
1260        dummy.ml.node = dlm->node_num;
1261        dlm_add_lock_to_array(&dummy, mres, DLM_BLOCKED_LIST);
1262}
1263
1264static inline int dlm_is_dummy_lock(struct dlm_ctxt *dlm,
1265                                    struct dlm_migratable_lock *ml,
1266                                    u8 *nodenum)
1267{
1268        if (unlikely(ml->cookie == 0 &&
1269            ml->type == LKM_IVMODE &&
1270            ml->convert_type == LKM_IVMODE &&
1271            ml->highest_blocked == LKM_IVMODE &&
1272            ml->list == DLM_BLOCKED_LIST)) {
1273                *nodenum = ml->node;
1274                return 1;
1275        }
1276        return 0;
1277}
1278
1279int dlm_send_one_lockres(struct dlm_ctxt *dlm, struct dlm_lock_resource *res,
1280                         struct dlm_migratable_lockres *mres,
1281                         u8 send_to, u8 flags)
1282{
1283        struct list_head *queue;
1284        int total_locks, i;
1285        u64 mig_cookie = 0;
1286        struct dlm_lock *lock;
1287        int ret = 0;
1288
1289        BUG_ON(!(flags & (DLM_MRES_RECOVERY|DLM_MRES_MIGRATION)));
1290
1291        mlog(0, "sending to %u\n", send_to);
1292
1293        total_locks = dlm_num_locks_in_lockres(res);
1294        if (total_locks > DLM_MAX_MIGRATABLE_LOCKS) {
1295                /* rare, but possible */
1296                mlog(0, "argh.  lockres has %d locks.  this will "
1297                          "require more than one network packet to "
1298                          "migrate\n", total_locks);
1299                mig_cookie = dlm_get_next_mig_cookie();
1300        }
1301
1302        dlm_init_migratable_lockres(mres, res->lockname.name,
1303                                    res->lockname.len, total_locks,
1304                                    mig_cookie, flags, res->owner);
1305
1306        total_locks = 0;
1307        for (i=DLM_GRANTED_LIST; i<=DLM_BLOCKED_LIST; i++) {
1308                queue = dlm_list_idx_to_ptr(res, i);
1309                list_for_each_entry(lock, queue, list) {
1310                        /* add another lock. */
1311                        total_locks++;
1312                        if (!dlm_add_lock_to_array(lock, mres, i))
1313                                continue;
1314
1315                        /* this filled the lock message,
1316                         * we must send it immediately. */
1317                        ret = dlm_send_mig_lockres_msg(dlm, mres, send_to,
1318                                                       res, total_locks);
1319                        if (ret < 0)
1320                                goto error;
1321                }
1322        }
1323        if (total_locks == 0) {
1324                /* send a dummy lock to indicate a mastery reference only */
1325                mlog(0, "%s:%.*s: sending dummy lock to %u, %s\n",
1326                     dlm->name, res->lockname.len, res->lockname.name,
1327                     send_to, flags & DLM_MRES_RECOVERY ? "recovery" :
1328                     "migration");
1329                dlm_add_dummy_lock(dlm, mres);
1330        }
1331        /* flush any remaining locks */
1332        ret = dlm_send_mig_lockres_msg(dlm, mres, send_to, res, total_locks);
1333        if (ret < 0)
1334                goto error;
1335        return ret;
1336
1337error:
1338        mlog(ML_ERROR, "%s: dlm_send_mig_lockres_msg returned %d\n",
1339             dlm->name, ret);
1340        if (!dlm_is_host_down(ret))
1341                BUG();
1342        mlog(0, "%s: node %u went down while sending %s "
1343             "lockres %.*s\n", dlm->name, send_to,
1344             flags & DLM_MRES_RECOVERY ?  "recovery" : "migration",
1345             res->lockname.len, res->lockname.name);
1346        return ret;
1347}
1348
1349
1350
1351/*
1352 * this message will contain no more than one page worth of
1353 * recovery data, and it will work on only one lockres.
1354 * there may be many locks in this page, and we may need to wait
1355 * for additional packets to complete all the locks (rare, but
1356 * possible).
1357 */
1358/*
1359 * NOTE: the allocation error cases here are scary
1360 * we really cannot afford to fail an alloc in recovery
1361 * do we spin?  returning an error only delays the problem really
1362 */
1363
1364int dlm_mig_lockres_handler(struct o2net_msg *msg, u32 len, void *data,
1365                            void **ret_data)
1366{
1367        struct dlm_ctxt *dlm = data;
1368        struct dlm_migratable_lockres *mres =
1369                (struct dlm_migratable_lockres *)msg->buf;
1370        int ret = 0;
1371        u8 real_master;
1372        u8 extra_refs = 0;
1373        char *buf = NULL;
1374        struct dlm_work_item *item = NULL;
1375        struct dlm_lock_resource *res = NULL;
1376        unsigned int hash;
1377
1378        if (!dlm_grab(dlm))
1379                return -EINVAL;
1380
1381        BUG_ON(!(mres->flags & (DLM_MRES_RECOVERY|DLM_MRES_MIGRATION)));
1382
1383        real_master = mres->master;
1384        if (real_master == DLM_LOCK_RES_OWNER_UNKNOWN) {
1385                /* cannot migrate a lockres with no master */
1386                BUG_ON(!(mres->flags & DLM_MRES_RECOVERY));
1387        }
1388
1389        mlog(0, "%s message received from node %u\n",
1390                  (mres->flags & DLM_MRES_RECOVERY) ?
1391                  "recovery" : "migration", mres->master);
1392        if (mres->flags & DLM_MRES_ALL_DONE)
1393                mlog(0, "all done flag.  all lockres data received!\n");
1394
1395        ret = -ENOMEM;
1396        buf = kmalloc(be16_to_cpu(msg->data_len), GFP_NOFS);
1397        item = kzalloc(sizeof(*item), GFP_NOFS);
1398        if (!buf || !item)
1399                goto leave;
1400
1401        /* lookup the lock to see if we have a secondary queue for this
1402         * already...  just add the locks in and this will have its owner
1403         * and RECOVERY flag changed when it completes. */
1404        hash = dlm_lockid_hash(mres->lockname, mres->lockname_len);
1405        spin_lock(&dlm->spinlock);
1406        res = __dlm_lookup_lockres_full(dlm, mres->lockname, mres->lockname_len,
1407                        hash);
1408        if (res) {
1409                /* this will get a ref on res */
1410                /* mark it as recovering/migrating and hash it */
1411                spin_lock(&res->spinlock);
1412                if (res->state & DLM_LOCK_RES_DROPPING_REF) {
1413                        mlog(0, "%s: node is attempting to migrate "
1414                                "lockres %.*s, but marked as dropping "
1415                                " ref!\n", dlm->name,
1416                                mres->lockname_len, mres->lockname);
1417                        ret = -EINVAL;
1418                        spin_unlock(&res->spinlock);
1419                        spin_unlock(&dlm->spinlock);
1420                        dlm_lockres_put(res);
1421                        goto leave;
1422                }
1423
1424                if (mres->flags & DLM_MRES_RECOVERY) {
1425                        res->state |= DLM_LOCK_RES_RECOVERING;
1426                } else {
1427                        if (res->state & DLM_LOCK_RES_MIGRATING) {
1428                                /* this is at least the second
1429                                 * lockres message */
1430                                mlog(0, "lock %.*s is already migrating\n",
1431                                          mres->lockname_len,
1432                                          mres->lockname);
1433                        } else if (res->state & DLM_LOCK_RES_RECOVERING) {
1434                                /* caller should BUG */
1435                                mlog(ML_ERROR, "node is attempting to migrate "
1436                                     "lock %.*s, but marked as recovering!\n",
1437                                     mres->lockname_len, mres->lockname);
1438                                ret = -EFAULT;
1439                                spin_unlock(&res->spinlock);
1440                                spin_unlock(&dlm->spinlock);
1441                                dlm_lockres_put(res);
1442                                goto leave;
1443                        }
1444                        res->state |= DLM_LOCK_RES_MIGRATING;
1445                }
1446                spin_unlock(&res->spinlock);
1447                spin_unlock(&dlm->spinlock);
1448        } else {
1449                spin_unlock(&dlm->spinlock);
1450                /* need to allocate, just like if it was
1451                 * mastered here normally  */
1452                res = dlm_new_lockres(dlm, mres->lockname, mres->lockname_len);
1453                if (!res)
1454                        goto leave;
1455
1456                /* to match the ref that we would have gotten if
1457                 * dlm_lookup_lockres had succeeded */
1458                dlm_lockres_get(res);
1459
1460                /* mark it as recovering/migrating and hash it */
1461                if (mres->flags & DLM_MRES_RECOVERY)
1462                        res->state |= DLM_LOCK_RES_RECOVERING;
1463                else
1464                        res->state |= DLM_LOCK_RES_MIGRATING;
1465
1466                spin_lock(&dlm->spinlock);
1467                __dlm_insert_lockres(dlm, res);
1468                spin_unlock(&dlm->spinlock);
1469
1470                /* Add an extra ref for this lock-less lockres lest the
1471                 * dlm_thread purges it before we get the chance to add
1472                 * locks to it */
1473                dlm_lockres_get(res);
1474
1475                /* There are three refs that need to be put.
1476                 * 1. Taken above.
1477                 * 2. kref_init in dlm_new_lockres()->dlm_init_lockres().
1478                 * 3. dlm_lookup_lockres()
1479                 * The first one is handled at the end of this function. The
1480                 * other two are handled in the worker thread after locks have
1481                 * been attached. Yes, we don't wait for purge time to match
1482                 * kref_init. The lockres will still have atleast one ref
1483                 * added because it is in the hash __dlm_insert_lockres() */
1484                extra_refs++;
1485
1486                /* now that the new lockres is inserted,
1487                 * make it usable by other processes */
1488                spin_lock(&res->spinlock);
1489                res->state &= ~DLM_LOCK_RES_IN_PROGRESS;
1490                spin_unlock(&res->spinlock);
1491                wake_up(&res->wq);
1492        }
1493
1494        /* at this point we have allocated everything we need,
1495         * and we have a hashed lockres with an extra ref and
1496         * the proper res->state flags. */
1497        ret = 0;
1498        spin_lock(&res->spinlock);
1499        /* drop this either when master requery finds a different master
1500         * or when a lock is added by the recovery worker */
1501        dlm_lockres_grab_inflight_ref(dlm, res);
1502        if (mres->master == DLM_LOCK_RES_OWNER_UNKNOWN) {
1503                /* migration cannot have an unknown master */
1504                BUG_ON(!(mres->flags & DLM_MRES_RECOVERY));
1505                mlog(0, "recovery has passed me a lockres with an "
1506                          "unknown owner.. will need to requery: "
1507                          "%.*s\n", mres->lockname_len, mres->lockname);
1508        } else {
1509                /* take a reference now to pin the lockres, drop it
1510                 * when locks are added in the worker */
1511                dlm_change_lockres_owner(dlm, res, dlm->node_num);
1512        }
1513        spin_unlock(&res->spinlock);
1514
1515        /* queue up work for dlm_mig_lockres_worker */
1516        dlm_grab(dlm);  /* get an extra ref for the work item */
1517        memcpy(buf, msg->buf, be16_to_cpu(msg->data_len));  /* copy the whole message */
1518        dlm_init_work_item(dlm, item, dlm_mig_lockres_worker, buf);
1519        item->u.ml.lockres = res; /* already have a ref */
1520        item->u.ml.real_master = real_master;
1521        item->u.ml.extra_ref = extra_refs;
1522        spin_lock(&dlm->work_lock);
1523        list_add_tail(&item->list, &dlm->work_list);
1524        spin_unlock(&dlm->work_lock);
1525        queue_work(dlm->dlm_worker, &dlm->dispatched_work);
1526
1527leave:
1528        /* One extra ref taken needs to be put here */
1529        if (extra_refs)
1530                dlm_lockres_put(res);
1531
1532        dlm_put(dlm);
1533        if (ret < 0) {
1534                kfree(buf);
1535                kfree(item);
1536                mlog_errno(ret);
1537        }
1538
1539        return ret;
1540}
1541
1542
1543static void dlm_mig_lockres_worker(struct dlm_work_item *item, void *data)
1544{
1545        struct dlm_ctxt *dlm;
1546        struct dlm_migratable_lockres *mres;
1547        int ret = 0;
1548        struct dlm_lock_resource *res;
1549        u8 real_master;
1550        u8 extra_ref;
1551
1552        dlm = item->dlm;
1553        mres = (struct dlm_migratable_lockres *)data;
1554
1555        res = item->u.ml.lockres;
1556        real_master = item->u.ml.real_master;
1557        extra_ref = item->u.ml.extra_ref;
1558
1559        if (real_master == DLM_LOCK_RES_OWNER_UNKNOWN) {
1560                /* this case is super-rare. only occurs if
1561                 * node death happens during migration. */
1562again:
1563                ret = dlm_lockres_master_requery(dlm, res, &real_master);
1564                if (ret < 0) {
1565                        mlog(0, "dlm_lockres_master_requery ret=%d\n",
1566                                  ret);
1567                        goto again;
1568                }
1569                if (real_master == DLM_LOCK_RES_OWNER_UNKNOWN) {
1570                        mlog(0, "lockres %.*s not claimed.  "
1571                                   "this node will take it.\n",
1572                                   res->lockname.len, res->lockname.name);
1573                } else {
1574                        spin_lock(&res->spinlock);
1575                        dlm_lockres_drop_inflight_ref(dlm, res);
1576                        spin_unlock(&res->spinlock);
1577                        mlog(0, "master needs to respond to sender "
1578                                  "that node %u still owns %.*s\n",
1579                                  real_master, res->lockname.len,
1580                                  res->lockname.name);
1581                        /* cannot touch this lockres */
1582                        goto leave;
1583                }
1584        }
1585
1586        ret = dlm_process_recovery_data(dlm, res, mres);
1587        if (ret < 0)
1588                mlog(0, "dlm_process_recovery_data returned  %d\n", ret);
1589        else
1590                mlog(0, "dlm_process_recovery_data succeeded\n");
1591
1592        if ((mres->flags & (DLM_MRES_MIGRATION|DLM_MRES_ALL_DONE)) ==
1593                           (DLM_MRES_MIGRATION|DLM_MRES_ALL_DONE)) {
1594                ret = dlm_finish_migration(dlm, res, mres->master);
1595                if (ret < 0)
1596                        mlog_errno(ret);
1597        }
1598
1599leave:
1600        /* See comment in dlm_mig_lockres_handler() */
1601        if (res) {
1602                if (extra_ref)
1603                        dlm_lockres_put(res);
1604                dlm_lockres_put(res);
1605        }
1606        kfree(data);
1607}
1608
1609
1610
1611static int dlm_lockres_master_requery(struct dlm_ctxt *dlm,
1612                                      struct dlm_lock_resource *res,
1613                                      u8 *real_master)
1614{
1615        struct dlm_node_iter iter;
1616        int nodenum;
1617        int ret = 0;
1618
1619        *real_master = DLM_LOCK_RES_OWNER_UNKNOWN;
1620
1621        /* we only reach here if one of the two nodes in a
1622         * migration died while the migration was in progress.
1623         * at this point we need to requery the master.  we
1624         * know that the new_master got as far as creating
1625         * an mle on at least one node, but we do not know
1626         * if any nodes had actually cleared the mle and set
1627         * the master to the new_master.  the old master
1628         * is supposed to set the owner to UNKNOWN in the
1629         * event of a new_master death, so the only possible
1630         * responses that we can get from nodes here are
1631         * that the master is new_master, or that the master
1632         * is UNKNOWN.
1633         * if all nodes come back with UNKNOWN then we know
1634         * the lock needs remastering here.
1635         * if any node comes back with a valid master, check
1636         * to see if that master is the one that we are
1637         * recovering.  if so, then the new_master died and
1638         * we need to remaster this lock.  if not, then the
1639         * new_master survived and that node will respond to
1640         * other nodes about the owner.
1641         * if there is an owner, this node needs to dump this
1642         * lockres and alert the sender that this lockres
1643         * was rejected. */
1644        spin_lock(&dlm->spinlock);
1645        dlm_node_iter_init(dlm->domain_map, &iter);
1646        spin_unlock(&dlm->spinlock);
1647
1648        while ((nodenum = dlm_node_iter_next(&iter)) >= 0) {
1649                /* do not send to self */
1650                if (nodenum == dlm->node_num)
1651                        continue;
1652                ret = dlm_do_master_requery(dlm, res, nodenum, real_master);
1653                if (ret < 0) {
1654                        mlog_errno(ret);
1655                        if (!dlm_is_host_down(ret))
1656                                BUG();
1657                        /* host is down, so answer for that node would be
1658                         * DLM_LOCK_RES_OWNER_UNKNOWN.  continue. */
1659                }
1660                if (*real_master != DLM_LOCK_RES_OWNER_UNKNOWN) {
1661                        mlog(0, "lock master is %u\n", *real_master);
1662                        break;
1663                }
1664        }
1665        return ret;
1666}
1667
1668
1669int dlm_do_master_requery(struct dlm_ctxt *dlm, struct dlm_lock_resource *res,
1670                          u8 nodenum, u8 *real_master)
1671{
1672        int ret = -EINVAL;
1673        struct dlm_master_requery req;
1674        int status = DLM_LOCK_RES_OWNER_UNKNOWN;
1675
1676        memset(&req, 0, sizeof(req));
1677        req.node_idx = dlm->node_num;
1678        req.namelen = res->lockname.len;
1679        memcpy(req.name, res->lockname.name, res->lockname.len);
1680
1681resend:
1682        ret = o2net_send_message(DLM_MASTER_REQUERY_MSG, dlm->key,
1683                                 &req, sizeof(req), nodenum, &status);
1684        if (ret < 0)
1685                mlog(ML_ERROR, "Error %d when sending message %u (key "
1686                     "0x%x) to node %u\n", ret, DLM_MASTER_REQUERY_MSG,
1687                     dlm->key, nodenum);
1688        else if (status == -ENOMEM) {
1689                mlog_errno(status);
1690                msleep(50);
1691                goto resend;
1692        } else {
1693                BUG_ON(status < 0);
1694                BUG_ON(status > DLM_LOCK_RES_OWNER_UNKNOWN);
1695                *real_master = (u8) (status & 0xff);
1696                mlog(0, "node %u responded to master requery with %u\n",
1697                          nodenum, *real_master);
1698                ret = 0;
1699        }
1700        return ret;
1701}
1702
1703
1704/* this function cannot error, so unless the sending
1705 * or receiving of the message failed, the owner can
1706 * be trusted */
1707int dlm_master_requery_handler(struct o2net_msg *msg, u32 len, void *data,
1708                               void **ret_data)
1709{
1710        struct dlm_ctxt *dlm = data;
1711        struct dlm_master_requery *req = (struct dlm_master_requery *)msg->buf;
1712        struct dlm_lock_resource *res = NULL;
1713        unsigned int hash;
1714        int master = DLM_LOCK_RES_OWNER_UNKNOWN;
1715        u32 flags = DLM_ASSERT_MASTER_REQUERY;
1716        int dispatched = 0;
1717
1718        if (!dlm_grab(dlm)) {
1719                /* since the domain has gone away on this
1720                 * node, the proper response is UNKNOWN */
1721                return master;
1722        }
1723
1724        hash = dlm_lockid_hash(req->name, req->namelen);
1725
1726        spin_lock(&dlm->spinlock);
1727        res = __dlm_lookup_lockres(dlm, req->name, req->namelen, hash);
1728        if (res) {
1729                spin_lock(&res->spinlock);
1730                master = res->owner;
1731                if (master == dlm->node_num) {
1732                        int ret = dlm_dispatch_assert_master(dlm, res,
1733                                                             0, 0, flags);
1734                        if (ret < 0) {
1735                                mlog_errno(ret);
1736                                spin_unlock(&res->spinlock);
1737                                dlm_lockres_put(res);
1738                                spin_unlock(&dlm->spinlock);
1739                                dlm_put(dlm);
1740                                /* sender will take care of this and retry */
1741                                return ret;
1742                        } else {
1743                                dispatched = 1;
1744                                __dlm_lockres_grab_inflight_worker(dlm, res);
1745                                spin_unlock(&res->spinlock);
1746                        }
1747                } else {
1748                        /* put.. incase we are not the master */
1749                        spin_unlock(&res->spinlock);
1750                        dlm_lockres_put(res);
1751                }
1752        }
1753        spin_unlock(&dlm->spinlock);
1754
1755        if (!dispatched)
1756                dlm_put(dlm);
1757        return master;
1758}
1759
1760static inline struct list_head *
1761dlm_list_num_to_pointer(struct dlm_lock_resource *res, int list_num)
1762{
1763        struct list_head *ret;
1764        BUG_ON(list_num < 0);
1765        BUG_ON(list_num > 2);
1766        ret = &(res->granted);
1767        ret += list_num;
1768        return ret;
1769}
1770/* TODO: do ast flush business
1771 * TODO: do MIGRATING and RECOVERING spinning
1772 */
1773
1774/*
1775* NOTE about in-flight requests during migration:
1776*
1777* Before attempting the migrate, the master has marked the lockres as
1778* MIGRATING and then flushed all of its pending ASTS.  So any in-flight
1779* requests either got queued before the MIGRATING flag got set, in which
1780* case the lock data will reflect the change and a return message is on
1781* the way, or the request failed to get in before MIGRATING got set.  In
1782* this case, the caller will be told to spin and wait for the MIGRATING
1783* flag to be dropped, then recheck the master.
1784* This holds true for the convert, cancel and unlock cases, and since lvb
1785* updates are tied to these same messages, it applies to lvb updates as
1786* well.  For the lock case, there is no way a lock can be on the master
1787* queue and not be on the secondary queue since the lock is always added
1788* locally first.  This means that the new target node will never be sent
1789* a lock that he doesn't already have on the list.
1790* In total, this means that the local lock is correct and should not be
1791* updated to match the one sent by the master.  Any messages sent back
1792* from the master before the MIGRATING flag will bring the lock properly
1793* up-to-date, and the change will be ordered properly for the waiter.
1794* We will *not* attempt to modify the lock underneath the waiter.
1795*/
1796
1797static int dlm_process_recovery_data(struct dlm_ctxt *dlm,
1798                                     struct dlm_lock_resource *res,
1799                                     struct dlm_migratable_lockres *mres)
1800{
1801        struct dlm_migratable_lock *ml;
1802        struct list_head *queue, *iter;
1803        struct list_head *tmpq = NULL;
1804        struct dlm_lock *newlock = NULL;
1805        struct dlm_lockstatus *lksb = NULL;
1806        int ret = 0;
1807        int i, j, bad;
1808        struct dlm_lock *lock;
1809        u8 from = O2NM_MAX_NODES;
1810        unsigned int added = 0;
1811        __be64 c;
1812
1813        mlog(0, "running %d locks for this lockres\n", mres->num_locks);
1814        for (i=0; i<mres->num_locks; i++) {
1815                ml = &(mres->ml[i]);
1816
1817                if (dlm_is_dummy_lock(dlm, ml, &from)) {
1818                        /* placeholder, just need to set the refmap bit */
1819                        BUG_ON(mres->num_locks != 1);
1820                        mlog(0, "%s:%.*s: dummy lock for %u\n",
1821                             dlm->name, mres->lockname_len, mres->lockname,
1822                             from);
1823                        spin_lock(&res->spinlock);
1824                        dlm_lockres_set_refmap_bit(dlm, res, from);
1825                        spin_unlock(&res->spinlock);
1826                        added++;
1827                        break;
1828                }
1829                BUG_ON(ml->highest_blocked != LKM_IVMODE);
1830                newlock = NULL;
1831                lksb = NULL;
1832
1833                queue = dlm_list_num_to_pointer(res, ml->list);
1834                tmpq = NULL;
1835
1836                /* if the lock is for the local node it needs to
1837                 * be moved to the proper location within the queue.
1838                 * do not allocate a new lock structure. */
1839                if (ml->node == dlm->node_num) {
1840                        /* MIGRATION ONLY! */
1841                        BUG_ON(!(mres->flags & DLM_MRES_MIGRATION));
1842
1843                        lock = NULL;
1844                        spin_lock(&res->spinlock);
1845                        for (j = DLM_GRANTED_LIST; j <= DLM_BLOCKED_LIST; j++) {
1846                                tmpq = dlm_list_idx_to_ptr(res, j);
1847                                list_for_each(iter, tmpq) {
1848                                        lock = list_entry(iter,
1849                                                  struct dlm_lock, list);
1850                                        if (lock->ml.cookie == ml->cookie)
1851                                                break;
1852                                        lock = NULL;
1853                                }
1854                                if (lock)
1855                                        break;
1856                        }
1857
1858                        /* lock is always created locally first, and
1859                         * destroyed locally last.  it must be on the list */
1860                        if (!lock) {
1861                                c = ml->cookie;
1862                                mlog(ML_ERROR, "Could not find local lock "
1863                                               "with cookie %u:%llu, node %u, "
1864                                               "list %u, flags 0x%x, type %d, "
1865                                               "conv %d, highest blocked %d\n",
1866                                     dlm_get_lock_cookie_node(be64_to_cpu(c)),
1867                                     dlm_get_lock_cookie_seq(be64_to_cpu(c)),
1868                                     ml->node, ml->list, ml->flags, ml->type,
1869                                     ml->convert_type, ml->highest_blocked);
1870                                __dlm_print_one_lock_resource(res);
1871                                BUG();
1872                        }
1873
1874                        if (lock->ml.node != ml->node) {
1875                                c = lock->ml.cookie;
1876                                mlog(ML_ERROR, "Mismatched node# in lock "
1877                                     "cookie %u:%llu, name %.*s, node %u\n",
1878                                     dlm_get_lock_cookie_node(be64_to_cpu(c)),
1879                                     dlm_get_lock_cookie_seq(be64_to_cpu(c)),
1880                                     res->lockname.len, res->lockname.name,
1881                                     lock->ml.node);
1882                                c = ml->cookie;
1883                                mlog(ML_ERROR, "Migrate lock cookie %u:%llu, "
1884                                     "node %u, list %u, flags 0x%x, type %d, "
1885                                     "conv %d, highest blocked %d\n",
1886                                     dlm_get_lock_cookie_node(be64_to_cpu(c)),
1887                                     dlm_get_lock_cookie_seq(be64_to_cpu(c)),
1888                                     ml->node, ml->list, ml->flags, ml->type,
1889                                     ml->convert_type, ml->highest_blocked);
1890                                __dlm_print_one_lock_resource(res);
1891                                BUG();
1892                        }
1893
1894                        if (tmpq != queue) {
1895                                c = ml->cookie;
1896                                mlog(0, "Lock cookie %u:%llu was on list %u "
1897                                     "instead of list %u for %.*s\n",
1898                                     dlm_get_lock_cookie_node(be64_to_cpu(c)),
1899                                     dlm_get_lock_cookie_seq(be64_to_cpu(c)),
1900                                     j, ml->list, res->lockname.len,
1901                                     res->lockname.name);
1902                                __dlm_print_one_lock_resource(res);
1903                                spin_unlock(&res->spinlock);
1904                                continue;
1905                        }
1906
1907                        /* see NOTE above about why we do not update
1908                         * to match the master here */
1909
1910                        /* move the lock to its proper place */
1911                        /* do not alter lock refcount.  switching lists. */
1912                        list_move_tail(&lock->list, queue);
1913                        spin_unlock(&res->spinlock);
1914                        added++;
1915
1916                        mlog(0, "just reordered a local lock!\n");
1917                        continue;
1918                }
1919
1920                /* lock is for another node. */
1921                newlock = dlm_new_lock(ml->type, ml->node,
1922                                       be64_to_cpu(ml->cookie), NULL);
1923                if (!newlock) {
1924                        ret = -ENOMEM;
1925                        goto leave;
1926                }
1927                lksb = newlock->lksb;
1928                dlm_lock_attach_lockres(newlock, res);
1929
1930                if (ml->convert_type != LKM_IVMODE) {
1931                        BUG_ON(queue != &res->converting);
1932                        newlock->ml.convert_type = ml->convert_type;
1933                }
1934                lksb->flags |= (ml->flags &
1935                                (DLM_LKSB_PUT_LVB|DLM_LKSB_GET_LVB));
1936
1937                if (ml->type == LKM_NLMODE)
1938                        goto skip_lvb;
1939
1940                /*
1941                 * If the lock is in the blocked list it can't have a valid lvb,
1942                 * so skip it
1943                 */
1944                if (ml->list == DLM_BLOCKED_LIST)
1945                        goto skip_lvb;
1946
1947                if (!dlm_lvb_is_empty(mres->lvb)) {
1948                        if (lksb->flags & DLM_LKSB_PUT_LVB) {
1949                                /* other node was trying to update
1950                                 * lvb when node died.  recreate the
1951                                 * lksb with the updated lvb. */
1952                                memcpy(lksb->lvb, mres->lvb, DLM_LVB_LEN);
1953                                /* the lock resource lvb update must happen
1954                                 * NOW, before the spinlock is dropped.
1955                                 * we no longer wait for the AST to update
1956                                 * the lvb. */
1957                                memcpy(res->lvb, mres->lvb, DLM_LVB_LEN);
1958                        } else {
1959                                /* otherwise, the node is sending its
1960                                 * most recent valid lvb info */
1961                                BUG_ON(ml->type != LKM_EXMODE &&
1962                                       ml->type != LKM_PRMODE);
1963                                if (!dlm_lvb_is_empty(res->lvb) &&
1964                                    (ml->type == LKM_EXMODE ||
1965                                     memcmp(res->lvb, mres->lvb, DLM_LVB_LEN))) {
1966                                        int i;
1967                                        mlog(ML_ERROR, "%s:%.*s: received bad "
1968                                             "lvb! type=%d\n", dlm->name,
1969                                             res->lockname.len,
1970                                             res->lockname.name, ml->type);
1971                                        printk("lockres lvb=[");
1972                                        for (i=0; i<DLM_LVB_LEN; i++)
1973                                                printk("%02x", res->lvb[i]);
1974                                        printk("]\nmigrated lvb=[");
1975                                        for (i=0; i<DLM_LVB_LEN; i++)
1976                                                printk("%02x", mres->lvb[i]);
1977                                        printk("]\n");
1978                                        dlm_print_one_lock_resource(res);
1979                                        BUG();
1980                                }
1981                                memcpy(res->lvb, mres->lvb, DLM_LVB_LEN);
1982                        }
1983                }
1984skip_lvb:
1985
1986                /* NOTE:
1987                 * wrt lock queue ordering and recovery:
1988                 *    1. order of locks on granted queue is
1989                 *       meaningless.
1990                 *    2. order of locks on converting queue is
1991                 *       LOST with the node death.  sorry charlie.
1992                 *    3. order of locks on the blocked queue is
1993                 *       also LOST.
1994                 * order of locks does not affect integrity, it
1995                 * just means that a lock request may get pushed
1996                 * back in line as a result of the node death.
1997                 * also note that for a given node the lock order
1998                 * for its secondary queue locks is preserved
1999                 * relative to each other, but clearly *not*
2000                 * preserved relative to locks from other nodes.
2001                 */
2002                bad = 0;
2003                spin_lock(&res->spinlock);
2004                list_for_each_entry(lock, queue, list) {
2005                        if (lock->ml.cookie == ml->cookie) {
2006                                c = lock->ml.cookie;
2007                                mlog(ML_ERROR, "%s:%.*s: %u:%llu: lock already "
2008                                     "exists on this lockres!\n", dlm->name,
2009                                     res->lockname.len, res->lockname.name,
2010                                     dlm_get_lock_cookie_node(be64_to_cpu(c)),
2011                                     dlm_get_lock_cookie_seq(be64_to_cpu(c)));
2012
2013                                mlog(ML_NOTICE, "sent lock: type=%d, conv=%d, "
2014                                     "node=%u, cookie=%u:%llu, queue=%d\n",
2015                                     ml->type, ml->convert_type, ml->node,
2016                                     dlm_get_lock_cookie_node(be64_to_cpu(ml->cookie)),
2017                                     dlm_get_lock_cookie_seq(be64_to_cpu(ml->cookie)),
2018                                     ml->list);
2019
2020                                __dlm_print_one_lock_resource(res);
2021                                bad = 1;
2022                                break;
2023                        }
2024                }
2025                if (!bad) {
2026                        dlm_lock_get(newlock);
2027                        if (mres->flags & DLM_MRES_RECOVERY &&
2028                                        ml->list == DLM_CONVERTING_LIST &&
2029                                        newlock->ml.type >
2030                                        newlock->ml.convert_type) {
2031                                /* newlock is doing downconvert, add it to the
2032                                 * head of converting list */
2033                                list_add(&newlock->list, queue);
2034                        } else
2035                                list_add_tail(&newlock->list, queue);
2036                        mlog(0, "%s:%.*s: added lock for node %u, "
2037                             "setting refmap bit\n", dlm->name,
2038                             res->lockname.len, res->lockname.name, ml->node);
2039                        dlm_lockres_set_refmap_bit(dlm, res, ml->node);
2040                        added++;
2041                }
2042                spin_unlock(&res->spinlock);
2043        }
2044        mlog(0, "done running all the locks\n");
2045
2046leave:
2047        /* balance the ref taken when the work was queued */
2048        spin_lock(&res->spinlock);
2049        dlm_lockres_drop_inflight_ref(dlm, res);
2050        spin_unlock(&res->spinlock);
2051
2052        if (ret < 0)
2053                mlog_errno(ret);
2054
2055        return ret;
2056}
2057
2058void dlm_move_lockres_to_recovery_list(struct dlm_ctxt *dlm,
2059                                       struct dlm_lock_resource *res)
2060{
2061        int i;
2062        struct list_head *queue;
2063        struct dlm_lock *lock, *next;
2064
2065        assert_spin_locked(&dlm->spinlock);
2066        assert_spin_locked(&res->spinlock);
2067        res->state |= DLM_LOCK_RES_RECOVERING;
2068        if (!list_empty(&res->recovering)) {
2069                mlog(0,
2070                     "Recovering res %s:%.*s, is already on recovery list!\n",
2071                     dlm->name, res->lockname.len, res->lockname.name);
2072                list_del_init(&res->recovering);
2073                dlm_lockres_put(res);
2074        }
2075        /* We need to hold a reference while on the recovery list */
2076        dlm_lockres_get(res);
2077        list_add_tail(&res->recovering, &dlm->reco.resources);
2078
2079        /* find any pending locks and put them back on proper list */
2080        for (i=DLM_BLOCKED_LIST; i>=DLM_GRANTED_LIST; i--) {
2081                queue = dlm_list_idx_to_ptr(res, i);
2082                list_for_each_entry_safe(lock, next, queue, list) {
2083                        dlm_lock_get(lock);
2084                        if (lock->convert_pending) {
2085                                /* move converting lock back to granted */
2086                                mlog(0, "node died with convert pending "
2087                                     "on %.*s. move back to granted list.\n",
2088                                     res->lockname.len, res->lockname.name);
2089                                dlm_revert_pending_convert(res, lock);
2090                                lock->convert_pending = 0;
2091                        } else if (lock->lock_pending) {
2092                                /* remove pending lock requests completely */
2093                                BUG_ON(i != DLM_BLOCKED_LIST);
2094                                mlog(0, "node died with lock pending "
2095                                     "on %.*s. remove from blocked list and skip.\n",
2096                                     res->lockname.len, res->lockname.name);
2097                                /* lock will be floating until ref in
2098                                 * dlmlock_remote is freed after the network
2099                                 * call returns.  ok for it to not be on any
2100                                 * list since no ast can be called
2101                                 * (the master is dead). */
2102                                dlm_revert_pending_lock(res, lock);
2103                                lock->lock_pending = 0;
2104                        } else if (lock->unlock_pending) {
2105                                /* if an unlock was in progress, treat as
2106                                 * if this had completed successfully
2107                                 * before sending this lock state to the
2108                                 * new master.  note that the dlm_unlock
2109                                 * call is still responsible for calling
2110                                 * the unlockast.  that will happen after
2111                                 * the network call times out.  for now,
2112                                 * just move lists to prepare the new
2113                                 * recovery master.  */
2114                                BUG_ON(i != DLM_GRANTED_LIST);
2115                                mlog(0, "node died with unlock pending "
2116                                     "on %.*s. remove from blocked list and skip.\n",
2117                                     res->lockname.len, res->lockname.name);
2118                                dlm_commit_pending_unlock(res, lock);
2119                                lock->unlock_pending = 0;
2120                        } else if (lock->cancel_pending) {
2121                                /* if a cancel was in progress, treat as
2122                                 * if this had completed successfully
2123                                 * before sending this lock state to the
2124                                 * new master */
2125                                BUG_ON(i != DLM_CONVERTING_LIST);
2126                                mlog(0, "node died with cancel pending "
2127                                     "on %.*s. move back to granted list.\n",
2128                                     res->lockname.len, res->lockname.name);
2129                                dlm_commit_pending_cancel(res, lock);
2130                                lock->cancel_pending = 0;
2131                        }
2132                        dlm_lock_put(lock);
2133                }
2134        }
2135}
2136
2137
2138
2139/* removes all recovered locks from the recovery list.
2140 * sets the res->owner to the new master.
2141 * unsets the RECOVERY flag and wakes waiters. */
2142static void dlm_finish_local_lockres_recovery(struct dlm_ctxt *dlm,
2143                                              u8 dead_node, u8 new_master)
2144{
2145        int i;
2146        struct hlist_head *bucket;
2147        struct dlm_lock_resource *res, *next;
2148
2149        assert_spin_locked(&dlm->spinlock);
2150
2151        list_for_each_entry_safe(res, next, &dlm->reco.resources, recovering) {
2152                if (res->owner == dead_node) {
2153                        mlog(0, "%s: res %.*s, Changing owner from %u to %u\n",
2154                             dlm->name, res->lockname.len, res->lockname.name,
2155                             res->owner, new_master);
2156                        list_del_init(&res->recovering);
2157                        spin_lock(&res->spinlock);
2158                        /* new_master has our reference from
2159                         * the lock state sent during recovery */
2160                        dlm_change_lockres_owner(dlm, res, new_master);
2161                        res->state &= ~DLM_LOCK_RES_RECOVERING;
2162                        if (__dlm_lockres_has_locks(res))
2163                                __dlm_dirty_lockres(dlm, res);
2164                        spin_unlock(&res->spinlock);
2165                        wake_up(&res->wq);
2166                        dlm_lockres_put(res);
2167                }
2168        }
2169
2170        /* this will become unnecessary eventually, but
2171         * for now we need to run the whole hash, clear
2172         * the RECOVERING state and set the owner
2173         * if necessary */
2174        for (i = 0; i < DLM_HASH_BUCKETS; i++) {
2175                bucket = dlm_lockres_hash(dlm, i);
2176                hlist_for_each_entry(res, bucket, hash_node) {
2177                        if (res->state & DLM_LOCK_RES_RECOVERY_WAITING) {
2178                                spin_lock(&res->spinlock);
2179                                res->state &= ~DLM_LOCK_RES_RECOVERY_WAITING;
2180                                spin_unlock(&res->spinlock);
2181                                wake_up(&res->wq);
2182                        }
2183
2184                        if (!(res->state & DLM_LOCK_RES_RECOVERING))
2185                                continue;
2186
2187                        if (res->owner != dead_node &&
2188                            res->owner != dlm->node_num)
2189                                continue;
2190
2191                        if (!list_empty(&res->recovering)) {
2192                                list_del_init(&res->recovering);
2193                                dlm_lockres_put(res);
2194                        }
2195
2196                        /* new_master has our reference from
2197                         * the lock state sent during recovery */
2198                        mlog(0, "%s: res %.*s, Changing owner from %u to %u\n",
2199                             dlm->name, res->lockname.len, res->lockname.name,
2200                             res->owner, new_master);
2201                        spin_lock(&res->spinlock);
2202                        dlm_change_lockres_owner(dlm, res, new_master);
2203                        res->state &= ~DLM_LOCK_RES_RECOVERING;
2204                        if (__dlm_lockres_has_locks(res))
2205                                __dlm_dirty_lockres(dlm, res);
2206                        spin_unlock(&res->spinlock);
2207                        wake_up(&res->wq);
2208                }
2209        }
2210}
2211
2212static inline int dlm_lvb_needs_invalidation(struct dlm_lock *lock, int local)
2213{
2214        if (local) {
2215                if (lock->ml.type != LKM_EXMODE &&
2216                    lock->ml.type != LKM_PRMODE)
2217                        return 1;
2218        } else if (lock->ml.type == LKM_EXMODE)
2219                return 1;
2220        return 0;
2221}
2222
2223static void dlm_revalidate_lvb(struct dlm_ctxt *dlm,
2224                               struct dlm_lock_resource *res, u8 dead_node)
2225{
2226        struct list_head *queue;
2227        struct dlm_lock *lock;
2228        int blank_lvb = 0, local = 0;
2229        int i;
2230        u8 search_node;
2231
2232        assert_spin_locked(&dlm->spinlock);
2233        assert_spin_locked(&res->spinlock);
2234
2235        if (res->owner == dlm->node_num)
2236                /* if this node owned the lockres, and if the dead node
2237                 * had an EX when he died, blank out the lvb */
2238                search_node = dead_node;
2239        else {
2240                /* if this is a secondary lockres, and we had no EX or PR
2241                 * locks granted, we can no longer trust the lvb */
2242                search_node = dlm->node_num;
2243                local = 1;  /* check local state for valid lvb */
2244        }
2245
2246        for (i=DLM_GRANTED_LIST; i<=DLM_CONVERTING_LIST; i++) {
2247                queue = dlm_list_idx_to_ptr(res, i);
2248                list_for_each_entry(lock, queue, list) {
2249                        if (lock->ml.node == search_node) {
2250                                if (dlm_lvb_needs_invalidation(lock, local)) {
2251                                        /* zero the lksb lvb and lockres lvb */
2252                                        blank_lvb = 1;
2253                                        memset(lock->lksb->lvb, 0, DLM_LVB_LEN);
2254                                }
2255                        }
2256                }
2257        }
2258
2259        if (blank_lvb) {
2260                mlog(0, "clearing %.*s lvb, dead node %u had EX\n",
2261                     res->lockname.len, res->lockname.name, dead_node);
2262                memset(res->lvb, 0, DLM_LVB_LEN);
2263        }
2264}
2265
2266static void dlm_free_dead_locks(struct dlm_ctxt *dlm,
2267                                struct dlm_lock_resource *res, u8 dead_node)
2268{
2269        struct dlm_lock *lock, *next;
2270        unsigned int freed = 0;
2271
2272        /* this node is the lockres master:
2273         * 1) remove any stale locks for the dead node
2274         * 2) if the dead node had an EX when he died, blank out the lvb
2275         */
2276        assert_spin_locked(&dlm->spinlock);
2277        assert_spin_locked(&res->spinlock);
2278
2279        /* We do two dlm_lock_put(). One for removing from list and the other is
2280         * to force the DLM_UNLOCK_FREE_LOCK action so as to free the locks */
2281
2282        /* TODO: check pending_asts, pending_basts here */
2283        list_for_each_entry_safe(lock, next, &res->granted, list) {
2284                if (lock->ml.node == dead_node) {
2285                        list_del_init(&lock->list);
2286                        dlm_lock_put(lock);
2287                        /* Can't schedule DLM_UNLOCK_FREE_LOCK - do manually */
2288                        dlm_lock_put(lock);
2289                        freed++;
2290                }
2291        }
2292        list_for_each_entry_safe(lock, next, &res->converting, list) {
2293                if (lock->ml.node == dead_node) {
2294                        list_del_init(&lock->list);
2295                        dlm_lock_put(lock);
2296                        /* Can't schedule DLM_UNLOCK_FREE_LOCK - do manually */
2297                        dlm_lock_put(lock);
2298                        freed++;
2299                }
2300        }
2301        list_for_each_entry_safe(lock, next, &res->blocked, list) {
2302                if (lock->ml.node == dead_node) {
2303                        list_del_init(&lock->list);
2304                        dlm_lock_put(lock);
2305                        /* Can't schedule DLM_UNLOCK_FREE_LOCK - do manually */
2306                        dlm_lock_put(lock);
2307                        freed++;
2308                }
2309        }
2310
2311        if (freed) {
2312                mlog(0, "%s:%.*s: freed %u locks for dead node %u, "
2313                     "dropping ref from lockres\n", dlm->name,
2314                     res->lockname.len, res->lockname.name, freed, dead_node);
2315                if(!test_bit(dead_node, res->refmap)) {
2316                        mlog(ML_ERROR, "%s:%.*s: freed %u locks for dead node %u, "
2317                             "but ref was not set\n", dlm->name,
2318                             res->lockname.len, res->lockname.name, freed, dead_node);
2319                        __dlm_print_one_lock_resource(res);
2320                }
2321                res->state |= DLM_LOCK_RES_RECOVERY_WAITING;
2322                dlm_lockres_clear_refmap_bit(dlm, res, dead_node);
2323        } else if (test_bit(dead_node, res->refmap)) {
2324                mlog(0, "%s:%.*s: dead node %u had a ref, but had "
2325                     "no locks and had not purged before dying\n", dlm->name,
2326                     res->lockname.len, res->lockname.name, dead_node);
2327                dlm_lockres_clear_refmap_bit(dlm, res, dead_node);
2328        }
2329
2330        /* do not kick thread yet */
2331        __dlm_dirty_lockres(dlm, res);
2332}
2333
2334/* if this node is the recovery master, and there are no
2335 * locks for a given lockres owned by this node that are in
2336 * either PR or EX mode, zero out the lvb before requesting.
2337 *
2338 */
2339
2340
2341static void dlm_do_local_recovery_cleanup(struct dlm_ctxt *dlm, u8 dead_node)
2342{
2343        struct dlm_lock_resource *res;
2344        int i;
2345        struct hlist_head *bucket;
2346        struct hlist_node *tmp;
2347        struct dlm_lock *lock;
2348
2349
2350        /* purge any stale mles */
2351        dlm_clean_master_list(dlm, dead_node);
2352
2353        /*
2354         * now clean up all lock resources.  there are two rules:
2355         *
2356         * 1) if the dead node was the master, move the lockres
2357         *    to the recovering list.  set the RECOVERING flag.
2358         *    this lockres needs to be cleaned up before it can
2359         *    be used further.
2360         *
2361         * 2) if this node was the master, remove all locks from
2362         *    each of the lockres queues that were owned by the
2363         *    dead node.  once recovery finishes, the dlm thread
2364         *    can be kicked again to see if any ASTs or BASTs
2365         *    need to be fired as a result.
2366         */
2367        for (i = 0; i < DLM_HASH_BUCKETS; i++) {
2368                bucket = dlm_lockres_hash(dlm, i);
2369                hlist_for_each_entry_safe(res, tmp, bucket, hash_node) {
2370                        /* always prune any $RECOVERY entries for dead nodes,
2371                         * otherwise hangs can occur during later recovery */
2372                        if (dlm_is_recovery_lock(res->lockname.name,
2373                                                 res->lockname.len)) {
2374                                spin_lock(&res->spinlock);
2375                                list_for_each_entry(lock, &res->granted, list) {
2376                                        if (lock->ml.node == dead_node) {
2377                                                mlog(0, "AHA! there was "
2378                                                     "a $RECOVERY lock for dead "
2379                                                     "node %u (%s)!\n",
2380                                                     dead_node, dlm->name);
2381                                                list_del_init(&lock->list);
2382                                                dlm_lock_put(lock);
2383                                                /* Can't schedule
2384                                                 * DLM_UNLOCK_FREE_LOCK
2385                                                 * - do manually */
2386                                                dlm_lock_put(lock);
2387                                                break;
2388                                        }
2389                                }
2390
2391                                if ((res->owner == dead_node) &&
2392                                                        (res->state & DLM_LOCK_RES_DROPPING_REF)) {
2393                                        dlm_lockres_get(res);
2394                                        __dlm_do_purge_lockres(dlm, res);
2395                                        spin_unlock(&res->spinlock);
2396                                        wake_up(&res->wq);
2397                                        dlm_lockres_put(res);
2398                                        continue;
2399                                } else if (res->owner == dlm->node_num)
2400                                        dlm_lockres_clear_refmap_bit(dlm, res, dead_node);
2401                                spin_unlock(&res->spinlock);
2402                                continue;
2403                        }
2404                        spin_lock(&res->spinlock);
2405                        /* zero the lvb if necessary */
2406                        dlm_revalidate_lvb(dlm, res, dead_node);
2407                        if (res->owner == dead_node) {
2408                                if (res->state & DLM_LOCK_RES_DROPPING_REF) {
2409                                        mlog(0, "%s:%.*s: owned by "
2410                                                "dead node %u, this node was "
2411                                                "dropping its ref when master died. "
2412                                                "continue, purging the lockres.\n",
2413                                                dlm->name, res->lockname.len,
2414                                                res->lockname.name, dead_node);
2415                                        dlm_lockres_get(res);
2416                                        __dlm_do_purge_lockres(dlm, res);
2417                                        spin_unlock(&res->spinlock);
2418                                        wake_up(&res->wq);
2419                                        dlm_lockres_put(res);
2420                                        continue;
2421                                }
2422                                dlm_move_lockres_to_recovery_list(dlm, res);
2423                        } else if (res->owner == dlm->node_num) {
2424                                dlm_free_dead_locks(dlm, res, dead_node);
2425                                __dlm_lockres_calc_usage(dlm, res);
2426                        } else if (res->owner == DLM_LOCK_RES_OWNER_UNKNOWN) {
2427                                if (test_bit(dead_node, res->refmap)) {
2428                                        mlog(0, "%s:%.*s: dead node %u had a ref, but had "
2429                                                "no locks and had not purged before dying\n",
2430                                                dlm->name, res->lockname.len,
2431                                                res->lockname.name, dead_node);
2432                                        dlm_lockres_clear_refmap_bit(dlm, res, dead_node);
2433                                }
2434                        }
2435                        spin_unlock(&res->spinlock);
2436                }
2437        }
2438
2439}
2440
2441static void __dlm_hb_node_down(struct dlm_ctxt *dlm, int idx)
2442{
2443        assert_spin_locked(&dlm->spinlock);
2444
2445        if (dlm->reco.new_master == idx) {
2446                mlog(0, "%s: recovery master %d just died\n",
2447                     dlm->name, idx);
2448                if (dlm->reco.state & DLM_RECO_STATE_FINALIZE) {
2449                        /* finalize1 was reached, so it is safe to clear
2450                         * the new_master and dead_node.  that recovery
2451                         * is complete. */
2452                        mlog(0, "%s: dead master %d had reached "
2453                             "finalize1 state, clearing\n", dlm->name, idx);
2454                        dlm->reco.state &= ~DLM_RECO_STATE_FINALIZE;
2455                        __dlm_reset_recovery(dlm);
2456                }
2457        }
2458
2459        /* Clean up join state on node death. */
2460        if (dlm->joining_node == idx) {
2461                mlog(0, "Clearing join state for node %u\n", idx);
2462                __dlm_set_joining_node(dlm, DLM_LOCK_RES_OWNER_UNKNOWN);
2463        }
2464
2465        /* check to see if the node is already considered dead */
2466        if (!test_bit(idx, dlm->live_nodes_map)) {
2467                mlog(0, "for domain %s, node %d is already dead. "
2468                     "another node likely did recovery already.\n",
2469                     dlm->name, idx);
2470                return;
2471        }
2472
2473        /* check to see if we do not care about this node */
2474        if (!test_bit(idx, dlm->domain_map)) {
2475                /* This also catches the case that we get a node down
2476                 * but haven't joined the domain yet. */
2477                mlog(0, "node %u already removed from domain!\n", idx);
2478                return;
2479        }
2480
2481        clear_bit(idx, dlm->live_nodes_map);
2482
2483        /* make sure local cleanup occurs before the heartbeat events */
2484        if (!test_bit(idx, dlm->recovery_map))
2485                dlm_do_local_recovery_cleanup(dlm, idx);
2486
2487        /* notify anything attached to the heartbeat events */
2488        dlm_hb_event_notify_attached(dlm, idx, 0);
2489
2490        mlog(0, "node %u being removed from domain map!\n", idx);
2491        clear_bit(idx, dlm->domain_map);
2492        clear_bit(idx, dlm->exit_domain_map);
2493        /* wake up migration waiters if a node goes down.
2494         * perhaps later we can genericize this for other waiters. */
2495        wake_up(&dlm->migration_wq);
2496
2497        set_bit(idx, dlm->recovery_map);
2498}
2499
2500void dlm_hb_node_down_cb(struct o2nm_node *node, int idx, void *data)
2501{
2502        struct dlm_ctxt *dlm = data;
2503
2504        if (!dlm_grab(dlm))
2505                return;
2506
2507        /*
2508         * This will notify any dlm users that a node in our domain
2509         * went away without notifying us first.
2510         */
2511        if (test_bit(idx, dlm->domain_map))
2512                dlm_fire_domain_eviction_callbacks(dlm, idx);
2513
2514        spin_lock(&dlm->spinlock);
2515        __dlm_hb_node_down(dlm, idx);
2516        spin_unlock(&dlm->spinlock);
2517
2518        dlm_put(dlm);
2519}
2520
2521void dlm_hb_node_up_cb(struct o2nm_node *node, int idx, void *data)
2522{
2523        struct dlm_ctxt *dlm = data;
2524
2525        if (!dlm_grab(dlm))
2526                return;
2527
2528        spin_lock(&dlm->spinlock);
2529        set_bit(idx, dlm->live_nodes_map);
2530        /* do NOT notify mle attached to the heartbeat events.
2531         * new nodes are not interesting in mastery until joined. */
2532        spin_unlock(&dlm->spinlock);
2533
2534        dlm_put(dlm);
2535}
2536
2537static void dlm_reco_ast(void *astdata)
2538{
2539        struct dlm_ctxt *dlm = astdata;
2540        mlog(0, "ast for recovery lock fired!, this=%u, dlm=%s\n",
2541             dlm->node_num, dlm->name);
2542}
2543static void dlm_reco_bast(void *astdata, int blocked_type)
2544{
2545        struct dlm_ctxt *dlm = astdata;
2546        mlog(0, "bast for recovery lock fired!, this=%u, dlm=%s\n",
2547             dlm->node_num, dlm->name);
2548}
2549static void dlm_reco_unlock_ast(void *astdata, enum dlm_status st)
2550{
2551        mlog(0, "unlockast for recovery lock fired!\n");
2552}
2553
2554/*
2555 * dlm_pick_recovery_master will continually attempt to use
2556 * dlmlock() on the special "$RECOVERY" lockres with the
2557 * LKM_NOQUEUE flag to get an EX.  every thread that enters
2558 * this function on each node racing to become the recovery
2559 * master will not stop attempting this until either:
2560 * a) this node gets the EX (and becomes the recovery master),
2561 * or b) dlm->reco.new_master gets set to some nodenum
2562 * != O2NM_INVALID_NODE_NUM (another node will do the reco).
2563 * so each time a recovery master is needed, the entire cluster
2564 * will sync at this point.  if the new master dies, that will
2565 * be detected in dlm_do_recovery */
2566static int dlm_pick_recovery_master(struct dlm_ctxt *dlm)
2567{
2568        enum dlm_status ret;
2569        struct dlm_lockstatus lksb;
2570        int status = -EINVAL;
2571
2572        mlog(0, "starting recovery of %s at %lu, dead=%u, this=%u\n",
2573             dlm->name, jiffies, dlm->reco.dead_node, dlm->node_num);
2574again:
2575        memset(&lksb, 0, sizeof(lksb));
2576
2577        ret = dlmlock(dlm, LKM_EXMODE, &lksb, LKM_NOQUEUE|LKM_RECOVERY,
2578                      DLM_RECOVERY_LOCK_NAME, DLM_RECOVERY_LOCK_NAME_LEN,
2579                      dlm_reco_ast, dlm, dlm_reco_bast);
2580
2581        mlog(0, "%s: dlmlock($RECOVERY) returned %d, lksb=%d\n",
2582             dlm->name, ret, lksb.status);
2583
2584        if (ret == DLM_NORMAL) {
2585                mlog(0, "dlm=%s dlmlock says I got it (this=%u)\n",
2586                     dlm->name, dlm->node_num);
2587
2588                /* got the EX lock.  check to see if another node
2589                 * just became the reco master */
2590                if (dlm_reco_master_ready(dlm)) {
2591                        mlog(0, "%s: got reco EX lock, but %u will "
2592                             "do the recovery\n", dlm->name,
2593                             dlm->reco.new_master);
2594                        status = -EEXIST;
2595                } else {
2596                        status = 0;
2597
2598                        /* see if recovery was already finished elsewhere */
2599                        spin_lock(&dlm->spinlock);
2600                        if (dlm->reco.dead_node == O2NM_INVALID_NODE_NUM) {
2601                                status = -EINVAL;
2602                                mlog(0, "%s: got reco EX lock, but "
2603                                     "node got recovered already\n", dlm->name);
2604                                if (dlm->reco.new_master != O2NM_INVALID_NODE_NUM) {
2605                                        mlog(ML_ERROR, "%s: new master is %u "
2606                                             "but no dead node!\n",
2607                                             dlm->name, dlm->reco.new_master);
2608                                        BUG();
2609                                }
2610                        }
2611                        spin_unlock(&dlm->spinlock);
2612                }
2613
2614                /* if this node has actually become the recovery master,
2615                 * set the master and send the messages to begin recovery */
2616                if (!status) {
2617                        mlog(0, "%s: dead=%u, this=%u, sending "
2618                             "begin_reco now\n", dlm->name,
2619                             dlm->reco.dead_node, dlm->node_num);
2620                        status = dlm_send_begin_reco_message(dlm,
2621                                      dlm->reco.dead_node);
2622                        /* this always succeeds */
2623                        BUG_ON(status);
2624
2625                        /* set the new_master to this node */
2626                        spin_lock(&dlm->spinlock);
2627                        dlm_set_reco_master(dlm, dlm->node_num);
2628                        spin_unlock(&dlm->spinlock);
2629                }
2630
2631                /* recovery lock is a special case.  ast will not get fired,
2632                 * so just go ahead and unlock it. */
2633                ret = dlmunlock(dlm, &lksb, 0, dlm_reco_unlock_ast, dlm);
2634                if (ret == DLM_DENIED) {
2635                        mlog(0, "got DLM_DENIED, trying LKM_CANCEL\n");
2636                        ret = dlmunlock(dlm, &lksb, LKM_CANCEL, dlm_reco_unlock_ast, dlm);
2637                }
2638                if (ret != DLM_NORMAL) {
2639                        /* this would really suck. this could only happen
2640                         * if there was a network error during the unlock
2641                         * because of node death.  this means the unlock
2642                         * is actually "done" and the lock structure is
2643                         * even freed.  we can continue, but only
2644                         * because this specific lock name is special. */
2645                        mlog(ML_ERROR, "dlmunlock returned %d\n", ret);
2646                }
2647        } else if (ret == DLM_NOTQUEUED) {
2648                mlog(0, "dlm=%s dlmlock says another node got it (this=%u)\n",
2649                     dlm->name, dlm->node_num);
2650                /* another node is master. wait on
2651                 * reco.new_master != O2NM_INVALID_NODE_NUM
2652                 * for at most one second */
2653                wait_event_timeout(dlm->dlm_reco_thread_wq,
2654                                         dlm_reco_master_ready(dlm),
2655                                         msecs_to_jiffies(1000));
2656                if (!dlm_reco_master_ready(dlm)) {
2657                        mlog(0, "%s: reco master taking awhile\n",
2658                             dlm->name);
2659                        goto again;
2660                }
2661                /* another node has informed this one that it is reco master */
2662                mlog(0, "%s: reco master %u is ready to recover %u\n",
2663                     dlm->name, dlm->reco.new_master, dlm->reco.dead_node);
2664                status = -EEXIST;
2665        } else if (ret == DLM_RECOVERING) {
2666                mlog(0, "dlm=%s dlmlock says master node died (this=%u)\n",
2667                     dlm->name, dlm->node_num);
2668                goto again;
2669        } else {
2670                struct dlm_lock_resource *res;
2671
2672                /* dlmlock returned something other than NOTQUEUED or NORMAL */
2673                mlog(ML_ERROR, "%s: got %s from dlmlock($RECOVERY), "
2674                     "lksb.status=%s\n", dlm->name, dlm_errname(ret),
2675                     dlm_errname(lksb.status));
2676                res = dlm_lookup_lockres(dlm, DLM_RECOVERY_LOCK_NAME,
2677                                         DLM_RECOVERY_LOCK_NAME_LEN);
2678                if (res) {
2679                        dlm_print_one_lock_resource(res);
2680                        dlm_lockres_put(res);
2681                } else {
2682                        mlog(ML_ERROR, "recovery lock not found\n");
2683                }
2684                BUG();
2685        }
2686
2687        return status;
2688}
2689
2690static int dlm_send_begin_reco_message(struct dlm_ctxt *dlm, u8 dead_node)
2691{
2692        struct dlm_begin_reco br;
2693        int ret = 0;
2694        struct dlm_node_iter iter;
2695        int nodenum;
2696        int status;
2697
2698        mlog(0, "%s: dead node is %u\n", dlm->name, dead_node);
2699
2700        spin_lock(&dlm->spinlock);
2701        dlm_node_iter_init(dlm->domain_map, &iter);
2702        spin_unlock(&dlm->spinlock);
2703
2704        clear_bit(dead_node, iter.node_map);
2705
2706        memset(&br, 0, sizeof(br));
2707        br.node_idx = dlm->node_num;
2708        br.dead_node = dead_node;
2709
2710        while ((nodenum = dlm_node_iter_next(&iter)) >= 0) {
2711                ret = 0;
2712                if (nodenum == dead_node) {
2713                        mlog(0, "not sending begin reco to dead node "
2714                                  "%u\n", dead_node);
2715                        continue;
2716                }
2717                if (nodenum == dlm->node_num) {
2718                        mlog(0, "not sending begin reco to self\n");
2719                        continue;
2720                }
2721retry:
2722                ret = -EINVAL;
2723                mlog(0, "attempting to send begin reco msg to %d\n",
2724                          nodenum);
2725                ret = o2net_send_message(DLM_BEGIN_RECO_MSG, dlm->key,
2726                                         &br, sizeof(br), nodenum, &status);
2727                /* negative status is handled ok by caller here */
2728                if (ret >= 0)
2729                        ret = status;
2730                if (dlm_is_host_down(ret)) {
2731                        /* node is down.  not involved in recovery
2732                         * so just keep going */
2733                        mlog(ML_NOTICE, "%s: node %u was down when sending "
2734                             "begin reco msg (%d)\n", dlm->name, nodenum, ret);
2735                        ret = 0;
2736                }
2737
2738                /*
2739                 * Prior to commit aad1b15310b9bcd59fa81ab8f2b1513b59553ea8,
2740                 * dlm_begin_reco_handler() returned EAGAIN and not -EAGAIN.
2741                 * We are handling both for compatibility reasons.
2742                 */
2743                if (ret == -EAGAIN || ret == EAGAIN) {
2744                        mlog(0, "%s: trying to start recovery of node "
2745                             "%u, but node %u is waiting for last recovery "
2746                             "to complete, backoff for a bit\n", dlm->name,
2747                             dead_node, nodenum);
2748                        msleep(100);
2749                        goto retry;
2750                }
2751                if (ret < 0) {
2752                        struct dlm_lock_resource *res;
2753
2754                        /* this is now a serious problem, possibly ENOMEM
2755                         * in the network stack.  must retry */
2756                        mlog_errno(ret);
2757                        mlog(ML_ERROR, "begin reco of dlm %s to node %u "
2758                             "returned %d\n", dlm->name, nodenum, ret);
2759                        res = dlm_lookup_lockres(dlm, DLM_RECOVERY_LOCK_NAME,
2760                                                 DLM_RECOVERY_LOCK_NAME_LEN);
2761                        if (res) {
2762                                dlm_print_one_lock_resource(res);
2763                                dlm_lockres_put(res);
2764                        } else {
2765                                mlog(ML_ERROR, "recovery lock not found\n");
2766                        }
2767                        /* sleep for a bit in hopes that we can avoid
2768                         * another ENOMEM */
2769                        msleep(100);
2770                        goto retry;
2771                }
2772        }
2773
2774        return ret;
2775}
2776
2777int dlm_begin_reco_handler(struct o2net_msg *msg, u32 len, void *data,
2778                           void **ret_data)
2779{
2780        struct dlm_ctxt *dlm = data;
2781        struct dlm_begin_reco *br = (struct dlm_begin_reco *)msg->buf;
2782
2783        /* ok to return 0, domain has gone away */
2784        if (!dlm_grab(dlm))
2785                return 0;
2786
2787        spin_lock(&dlm->spinlock);
2788        if (dlm->reco.state & DLM_RECO_STATE_FINALIZE) {
2789                mlog(0, "%s: node %u wants to recover node %u (%u:%u) "
2790                     "but this node is in finalize state, waiting on finalize2\n",
2791                     dlm->name, br->node_idx, br->dead_node,
2792                     dlm->reco.dead_node, dlm->reco.new_master);
2793                spin_unlock(&dlm->spinlock);
2794                dlm_put(dlm);
2795                return -EAGAIN;
2796        }
2797        spin_unlock(&dlm->spinlock);
2798
2799        mlog(0, "%s: node %u wants to recover node %u (%u:%u)\n",
2800             dlm->name, br->node_idx, br->dead_node,
2801             dlm->reco.dead_node, dlm->reco.new_master);
2802
2803        dlm_fire_domain_eviction_callbacks(dlm, br->dead_node);
2804
2805        spin_lock(&dlm->spinlock);
2806        if (dlm->reco.new_master != O2NM_INVALID_NODE_NUM) {
2807                if (test_bit(dlm->reco.new_master, dlm->recovery_map)) {
2808                        mlog(0, "%s: new_master %u died, changing "
2809                             "to %u\n", dlm->name, dlm->reco.new_master,
2810                             br->node_idx);
2811                } else {
2812                        mlog(0, "%s: new_master %u NOT DEAD, changing "
2813                             "to %u\n", dlm->name, dlm->reco.new_master,
2814                             br->node_idx);
2815                        /* may not have seen the new master as dead yet */
2816                }
2817        }
2818        if (dlm->reco.dead_node != O2NM_INVALID_NODE_NUM) {
2819                mlog(ML_NOTICE, "%s: dead_node previously set to %u, "
2820                     "node %u changing it to %u\n", dlm->name,
2821                     dlm->reco.dead_node, br->node_idx, br->dead_node);
2822        }
2823        dlm_set_reco_master(dlm, br->node_idx);
2824        dlm_set_reco_dead_node(dlm, br->dead_node);
2825        if (!test_bit(br->dead_node, dlm->recovery_map)) {
2826                mlog(0, "recovery master %u sees %u as dead, but this "
2827                     "node has not yet.  marking %u as dead\n",
2828                     br->node_idx, br->dead_node, br->dead_node);
2829                if (!test_bit(br->dead_node, dlm->domain_map) ||
2830                    !test_bit(br->dead_node, dlm->live_nodes_map))
2831                        mlog(0, "%u not in domain/live_nodes map "
2832                             "so setting it in reco map manually\n",
2833                             br->dead_node);
2834                /* force the recovery cleanup in __dlm_hb_node_down
2835                 * both of these will be cleared in a moment */
2836                set_bit(br->dead_node, dlm->domain_map);
2837                set_bit(br->dead_node, dlm->live_nodes_map);
2838                __dlm_hb_node_down(dlm, br->dead_node);
2839        }
2840        spin_unlock(&dlm->spinlock);
2841
2842        dlm_kick_recovery_thread(dlm);
2843
2844        mlog(0, "%s: recovery started by node %u, for %u (%u:%u)\n",
2845             dlm->name, br->node_idx, br->dead_node,
2846             dlm->reco.dead_node, dlm->reco.new_master);
2847
2848        dlm_put(dlm);
2849        return 0;
2850}
2851
2852#define DLM_FINALIZE_STAGE2  0x01
2853static int dlm_send_finalize_reco_message(struct dlm_ctxt *dlm)
2854{
2855        int ret = 0;
2856        struct dlm_finalize_reco fr;
2857        struct dlm_node_iter iter;
2858        int nodenum;
2859        int status;
2860        int stage = 1;
2861
2862        mlog(0, "finishing recovery for node %s:%u, "
2863             "stage %d\n", dlm->name, dlm->reco.dead_node, stage);
2864
2865        spin_lock(&dlm->spinlock);
2866        dlm_node_iter_init(dlm->domain_map, &iter);
2867        spin_unlock(&dlm->spinlock);
2868
2869stage2:
2870        memset(&fr, 0, sizeof(fr));
2871        fr.node_idx = dlm->node_num;
2872        fr.dead_node = dlm->reco.dead_node;
2873        if (stage == 2)
2874                fr.flags |= DLM_FINALIZE_STAGE2;
2875
2876        while ((nodenum = dlm_node_iter_next(&iter)) >= 0) {
2877                if (nodenum == dlm->node_num)
2878                        continue;
2879                ret = o2net_send_message(DLM_FINALIZE_RECO_MSG, dlm->key,
2880                                         &fr, sizeof(fr), nodenum, &status);
2881                if (ret >= 0)
2882                        ret = status;
2883                if (ret < 0) {
2884                        mlog(ML_ERROR, "Error %d when sending message %u (key "
2885                             "0x%x) to node %u\n", ret, DLM_FINALIZE_RECO_MSG,
2886                             dlm->key, nodenum);
2887                        if (dlm_is_host_down(ret)) {
2888                                /* this has no effect on this recovery
2889                                 * session, so set the status to zero to
2890                                 * finish out the last recovery */
2891                                mlog(ML_ERROR, "node %u went down after this "
2892                                     "node finished recovery.\n", nodenum);
2893                                ret = 0;
2894                                continue;
2895                        }
2896                        break;
2897                }
2898        }
2899        if (stage == 1) {
2900                /* reset the node_iter back to the top and send finalize2 */
2901                iter.curnode = -1;
2902                stage = 2;
2903                goto stage2;
2904        }
2905
2906        return ret;
2907}
2908
2909int dlm_finalize_reco_handler(struct o2net_msg *msg, u32 len, void *data,
2910                              void **ret_data)
2911{
2912        struct dlm_ctxt *dlm = data;
2913        struct dlm_finalize_reco *fr = (struct dlm_finalize_reco *)msg->buf;
2914        int stage = 1;
2915
2916        /* ok to return 0, domain has gone away */
2917        if (!dlm_grab(dlm))
2918                return 0;
2919
2920        if (fr->flags & DLM_FINALIZE_STAGE2)
2921                stage = 2;
2922
2923        mlog(0, "%s: node %u finalizing recovery stage%d of "
2924             "node %u (%u:%u)\n", dlm->name, fr->node_idx, stage,
2925             fr->dead_node, dlm->reco.dead_node, dlm->reco.new_master);
2926
2927        spin_lock(&dlm->spinlock);
2928
2929        if (dlm->reco.new_master != fr->node_idx) {
2930                mlog(ML_ERROR, "node %u sent recovery finalize msg, but node "
2931                     "%u is supposed to be the new master, dead=%u\n",
2932                     fr->node_idx, dlm->reco.new_master, fr->dead_node);
2933                BUG();
2934        }
2935        if (dlm->reco.dead_node != fr->dead_node) {
2936                mlog(ML_ERROR, "node %u sent recovery finalize msg for dead "
2937                     "node %u, but node %u is supposed to be dead\n",
2938                     fr->node_idx, fr->dead_node, dlm->reco.dead_node);
2939                BUG();
2940        }
2941
2942        switch (stage) {
2943                case 1:
2944                        dlm_finish_local_lockres_recovery(dlm, fr->dead_node, fr->node_idx);
2945                        if (dlm->reco.state & DLM_RECO_STATE_FINALIZE) {
2946                                mlog(ML_ERROR, "%s: received finalize1 from "
2947                                     "new master %u for dead node %u, but "
2948                                     "this node has already received it!\n",
2949                                     dlm->name, fr->node_idx, fr->dead_node);
2950                                dlm_print_reco_node_status(dlm);
2951                                BUG();
2952                        }
2953                        dlm->reco.state |= DLM_RECO_STATE_FINALIZE;
2954                        spin_unlock(&dlm->spinlock);
2955                        break;
2956                case 2:
2957                        if (!(dlm->reco.state & DLM_RECO_STATE_FINALIZE)) {
2958                                mlog(ML_ERROR, "%s: received finalize2 from "
2959                                     "new master %u for dead node %u, but "
2960                                     "this node did not have finalize1!\n",
2961                                     dlm->name, fr->node_idx, fr->dead_node);
2962                                dlm_print_reco_node_status(dlm);
2963                                BUG();
2964                        }
2965                        dlm->reco.state &= ~DLM_RECO_STATE_FINALIZE;
2966                        __dlm_reset_recovery(dlm);
2967                        spin_unlock(&dlm->spinlock);
2968                        dlm_kick_recovery_thread(dlm);
2969                        break;
2970        }
2971
2972        mlog(0, "%s: recovery done, reco master was %u, dead now %u, master now %u\n",
2973             dlm->name, fr->node_idx, dlm->reco.dead_node, dlm->reco.new_master);
2974
2975        dlm_put(dlm);
2976        return 0;
2977}
2978