fs/ocfs2/heartbeat.c

   1 /* -*- mode: c; c-basic-offset: 8; -*-
   2  * vim: noexpandtab sw=8 ts=8 sts=0:
   3  *
   4  * heartbeat.c
   5  *
   6  * Register ourselves with the heartbaet service, keep our node maps
   7  * up to date, and fire off recovery when needed.
   8  *
   9  * Copyright (C) 2002, 2004 Oracle.  All rights reserved.
  10  *
  11  * This program is free software; you can redistribute it and/or
  12  * modify it under the terms of the GNU General Public
  13  * License as published by the Free Software Foundation; either
  14  * version 2 of the License, or (at your option) any later version.
  15  *
  16  * This program is distributed in the hope that it will be useful,
  17  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  18  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  19  * General Public License for more details.
  20  *
  21  * You should have received a copy of the GNU General Public
  22  * License along with this program; if not, write to the
  23  * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
  24  * Boston, MA 021110-1307, USA.
  25  */
  26
  27 #include <linux/fs.h>
  28 #include <linux/types.h>
  29 #include <linux/slab.h>
  30 #include <linux/highmem.h>
  31 #include <linux/kmod.h>
  32
  33 #include <cluster/heartbeat.h>
  34 #include <cluster/nodemanager.h>
  35
  36 #include <dlm/dlmapi.h>
  37
  38 #define MLOG_MASK_PREFIX ML_SUPER
  39 #include <cluster/masklog.h>
  40
  41 #include "ocfs2.h"
  42
  43 #include "alloc.h"
  44 #include "heartbeat.h"
  45 #include "inode.h"
  46 #include "journal.h"
  47 #include "vote.h"
  48
  49 #include "buffer_head_io.h"
  50
  51 #define OCFS2_HB_NODE_DOWN_PRI     (0x0000002)
  52 #define OCFS2_HB_NODE_UP_PRI       OCFS2_HB_NODE_DOWN_PRI
  53
  54 static inline void __ocfs2_node_map_set_bit(struct ocfs2_node_map *map,
  55                                             int bit);
  56 static inline void __ocfs2_node_map_clear_bit(struct ocfs2_node_map *map,
  57                                               int bit);
  58 static inline int __ocfs2_node_map_is_empty(struct ocfs2_node_map *map);
  59 static void __ocfs2_node_map_dup(struct ocfs2_node_map *target,
  60                                  struct ocfs2_node_map *from);
  61 static void __ocfs2_node_map_set(struct ocfs2_node_map *target,
  62                                  struct ocfs2_node_map *from);
  63
  64 void ocfs2_init_node_maps(struct ocfs2_super *osb)
  65 {
  66         spin_lock_init(&osb->node_map_lock);
  67         ocfs2_node_map_init(&osb->mounted_map);
  68         ocfs2_node_map_init(&osb->recovery_map);
  69         ocfs2_node_map_init(&osb->umount_map);
  70 }
  71
  72 static void ocfs2_do_node_down(int node_num,
  73                                struct ocfs2_super *osb)
  74 {
  75         BUG_ON(osb->node_num == node_num);
  76
  77         mlog(0, "ocfs2: node down event for %d\n", node_num);
  78
  79         if (!osb->dlm) {
  80                 /*
  81                  * No DLM means we're not even ready to participate yet.
  82                  * We check the slots after the DLM comes up, so we will
  83                  * notice the node death then.  We can safely ignore it
  84                  * here.
  85                  */
  86                 return;
  87         }
  88
  89         if (ocfs2_node_map_test_bit(osb, &osb->umount_map, node_num)) {
  90                 /* If a node is in the umount map, then we've been
  91                  * expecting him to go down and we know ahead of time
  92                  * that recovery is not necessary. */
  93                 ocfs2_node_map_clear_bit(osb, &osb->umount_map, node_num);
  94                 return;
  95         }
  96
  97         ocfs2_recovery_thread(osb, node_num);
  98
  99         ocfs2_remove_node_from_vote_queues(osb, node_num);
 100 }
 101
 102 static void ocfs2_hb_node_down_cb(struct o2nm_node *node,
 103                                   int node_num,
 104                                   void *data)
 105 {
 106         ocfs2_do_node_down(node_num, (struct ocfs2_super *) data);
 107 }
 108
 109 /* Called from the dlm when it's about to evict a node. We may also
 110  * get a heartbeat callback later. */
 111 static void ocfs2_dlm_eviction_cb(int node_num,
 112                                   void *data)
 113 {
 114         struct ocfs2_super *osb = (struct ocfs2_super *) data;
 115         struct super_block *sb = osb->sb;
 116
 117         mlog(ML_NOTICE, "device (%u,%u): dlm has evicted node %d\n",
 118              MAJOR(sb->s_dev), MINOR(sb->s_dev), node_num);
 119
 120         ocfs2_do_node_down(node_num, osb);
 121 }
 122
 123 static void ocfs2_hb_node_up_cb(struct o2nm_node *node,
 124                                 int node_num,
 125                                 void *data)
 126 {
 127         struct ocfs2_super *osb = data;
 128
 129         BUG_ON(osb->node_num == node_num);
 130
 131         mlog(0, "node up event for %d\n", node_num);
 132         ocfs2_node_map_clear_bit(osb, &osb->umount_map, node_num);
 133 }
 134
 135 void ocfs2_setup_hb_callbacks(struct ocfs2_super *osb)
 136 {
 137         o2hb_setup_callback(&osb->osb_hb_down, O2HB_NODE_DOWN_CB,
 138                             ocfs2_hb_node_down_cb, osb,
 139                             OCFS2_HB_NODE_DOWN_PRI);
 140
 141         o2hb_setup_callback(&osb->osb_hb_up, O2HB_NODE_UP_CB,
 142                             ocfs2_hb_node_up_cb, osb, OCFS2_HB_NODE_UP_PRI);
 143
 144         /* Not exactly a heartbeat callback, but leads to essentially
 145          * the same path so we set it up here. */
 146         dlm_setup_eviction_cb(&osb->osb_eviction_cb,
 147                               ocfs2_dlm_eviction_cb,
 148                               osb);
 149 }
 150
 151 /* Most functions here are just stubs for now... */
 152 int ocfs2_register_hb_callbacks(struct ocfs2_super *osb)
 153 {
 154         int status;
 155
 156         status = o2hb_register_callback(&osb->osb_hb_down);
 157         if (status < 0) {
 158                 mlog_errno(status);
 159                 goto bail;
 160         }
 161
 162         status = o2hb_register_callback(&osb->osb_hb_up);
 163         if (status < 0)
 164                 mlog_errno(status);
 165
 166 bail:
 167         return status;
 168 }
 169
 170 void ocfs2_clear_hb_callbacks(struct ocfs2_super *osb)
 171 {
 172         int status;
 173
 174         status = o2hb_unregister_callback(&osb->osb_hb_down);
 175         if (status < 0)
 176                 mlog_errno(status);
 177
 178         status = o2hb_unregister_callback(&osb->osb_hb_up);
 179         if (status < 0)
 180                 mlog_errno(status);
 181 }
 182
 183 void ocfs2_stop_heartbeat(struct ocfs2_super *osb)
 184 {
 185         int ret;
 186         char *argv[5], *envp[3];
 187
 188         if (!osb->uuid_str) {
 189                 /* This can happen if we don't get far enough in mount... */
 190                 mlog(0, "No UUID with which to stop heartbeat!\n\n");
 191                 return;
 192         }
 193
 194         argv[0] = (char *)o2nm_get_hb_ctl_path();
 195         argv[1] = "-K";
 196         argv[2] = "-u";
 197         argv[3] = osb->uuid_str;
 198         argv[4] = NULL;
 199
 200         mlog(0, "Run: %s %s %s %s\n", argv[0], argv[1], argv[2], argv[3]);
 201
 202         /* minimal command environment taken from cpu_run_sbin_hotplug */
 203         envp[0] = "HOME=/";
 204         envp[1] = "PATH=/sbin:/bin:/usr/sbin:/usr/bin";
 205         envp[2] = NULL;
 206
 207         ret = call_usermodehelper(argv[0], argv, envp, 1);
 208         if (ret < 0)
 209                 mlog_errno(ret);
 210 }
 211
 212 /* special case -1 for now
 213  * TODO: should *really* make sure the calling func never passes -1!!  */
 214 void ocfs2_node_map_init(struct ocfs2_node_map *map)
 215 {
 216         map->num_nodes = OCFS2_NODE_MAP_MAX_NODES;
 217         memset(map->map, 0, BITS_TO_LONGS(OCFS2_NODE_MAP_MAX_NODES) *
 218                sizeof(unsigned long));
 219 }
 220
 221 static inline void __ocfs2_node_map_set_bit(struct ocfs2_node_map *map,
 222                                             int bit)
 223 {
 224         set_bit(bit, map->map);
 225 }
 226
 227 void ocfs2_node_map_set_bit(struct ocfs2_super *osb,
 228                             struct ocfs2_node_map *map,
 229                             int bit)
 230 {
 231         if (bit==-1)
 232                 return;
 233         BUG_ON(bit >= map->num_nodes);
 234         spin_lock(&osb->node_map_lock);
 235         __ocfs2_node_map_set_bit(map, bit);
 236         spin_unlock(&osb->node_map_lock);
 237 }
 238
 239 static inline void __ocfs2_node_map_clear_bit(struct ocfs2_node_map *map,
 240                                               int bit)
 241 {
 242         clear_bit(bit, map->map);
 243 }
 244
 245 void ocfs2_node_map_clear_bit(struct ocfs2_super *osb,
 246                               struct ocfs2_node_map *map,
 247                               int bit)
 248 {
 249         if (bit==-1)
 250                 return;
 251         BUG_ON(bit >= map->num_nodes);
 252         spin_lock(&osb->node_map_lock);
 253         __ocfs2_node_map_clear_bit(map, bit);
 254         spin_unlock(&osb->node_map_lock);
 255 }
 256
 257 int ocfs2_node_map_test_bit(struct ocfs2_super *osb,
 258                             struct ocfs2_node_map *map,
 259                             int bit)
 260 {
 261         int ret;
 262         if (bit >= map->num_nodes) {
 263                 mlog(ML_ERROR, "bit=%d map->num_nodes=%d\n", bit, map->num_nodes);
 264                 BUG();
 265         }
 266         spin_lock(&osb->node_map_lock);
 267         ret = test_bit(bit, map->map);
 268         spin_unlock(&osb->node_map_lock);
 269         return ret;
 270 }
 271
 272 static inline int __ocfs2_node_map_is_empty(struct ocfs2_node_map *map)
 273 {
 274         int bit;
 275         bit = find_next_bit(map->map, map->num_nodes, 0);
 276         if (bit < map->num_nodes)
 277                 return 0;
 278         return 1;
 279 }
 280
 281 int ocfs2_node_map_is_empty(struct ocfs2_super *osb,
 282                             struct ocfs2_node_map *map)
 283 {
 284         int ret;
 285         BUG_ON(map->num_nodes == 0);
 286         spin_lock(&osb->node_map_lock);
 287         ret = __ocfs2_node_map_is_empty(map);
 288         spin_unlock(&osb->node_map_lock);
 289         return ret;
 290 }
 291
 292 static void __ocfs2_node_map_dup(struct ocfs2_node_map *target,
 293                                  struct ocfs2_node_map *from)
 294 {
 295         BUG_ON(from->num_nodes == 0);
 296         ocfs2_node_map_init(target);
 297         __ocfs2_node_map_set(target, from);
 298 }
 299
 300 /* returns 1 if bit is the only bit set in target, 0 otherwise */
 301 int ocfs2_node_map_is_only(struct ocfs2_super *osb,
 302                            struct ocfs2_node_map *target,
 303                            int bit)
 304 {
 305         struct ocfs2_node_map temp;
 306         int ret;
 307
 308         spin_lock(&osb->node_map_lock);
 309         __ocfs2_node_map_dup(&temp, target);
 310         __ocfs2_node_map_clear_bit(&temp, bit);
 311         ret = __ocfs2_node_map_is_empty(&temp);
 312         spin_unlock(&osb->node_map_lock);
 313
 314         return ret;
 315 }
 316
 317 static void __ocfs2_node_map_set(struct ocfs2_node_map *target,
 318                                  struct ocfs2_node_map *from)
 319 {
 320         int num_longs, i;
 321
 322         BUG_ON(target->num_nodes != from->num_nodes);
 323         BUG_ON(target->num_nodes == 0);
 324
 325         num_longs = BITS_TO_LONGS(target->num_nodes);
 326         for (i = 0; i < num_longs; i++)
 327                 target->map[i] = from->map[i];
 328 }
 329
 330 /* Returns whether the recovery bit was actually set - it may not be
 331  * if a node is still marked as needing recovery */
 332 int ocfs2_recovery_map_set(struct ocfs2_super *osb,
 333                            int num)
 334 {
 335         int set = 0;
 336
 337         spin_lock(&osb->node_map_lock);
 338
 339         __ocfs2_node_map_clear_bit(&osb->mounted_map, num);
 340
 341         if (!test_bit(num, osb->recovery_map.map)) {
 342             __ocfs2_node_map_set_bit(&osb->recovery_map, num);
 343             set = 1;
 344         }
 345
 346         spin_unlock(&osb->node_map_lock);
 347
 348         return set;
 349 }
 350
 351 void ocfs2_recovery_map_clear(struct ocfs2_super *osb,
 352                               int num)
 353 {
 354         ocfs2_node_map_clear_bit(osb, &osb->recovery_map, num);
 355 }
 356
 357 int ocfs2_node_map_iterate(struct ocfs2_super *osb,
 358                            struct ocfs2_node_map *map,
 359                            int idx)
 360 {
 361         int i = idx;
 362
 363         idx = O2NM_INVALID_NODE_NUM;
 364         spin_lock(&osb->node_map_lock);
 365         if ((i != O2NM_INVALID_NODE_NUM) &&
 366             (i >= 0) &&
 367             (i < map->num_nodes)) {
 368                 while(i < map->num_nodes) {
 369                         if (test_bit(i, map->map)) {
 370                                 idx = i;
 371                                 break;
 372                         }
 373                         i++;
 374                 }
 375         }
 376         spin_unlock(&osb->node_map_lock);
 377         return idx;
 378 }