release/src-rt-6.x/linux/linux-2.6/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         ocfs2_node_map_init(&osb->osb_recovering_orphan_dirs);
  71 }
  72
  73 static void ocfs2_do_node_down(int node_num,
  74                                struct ocfs2_super *osb)
  75 {
  76         BUG_ON(osb->node_num == node_num);
  77
  78         mlog(0, "ocfs2: node down event for %d\n", node_num);
  79
  80         if (!osb->dlm) {
  81                 /*
  82                  * No DLM means we're not even ready to participate yet.
  83                  * We check the slots after the DLM comes up, so we will
  84                  * notice the node death then.  We can safely ignore it
  85                  * here.
  86                  */
  87                 return;
  88         }
  89
  90         if (ocfs2_node_map_test_bit(osb, &osb->umount_map, node_num)) {
  91                 /* If a node is in the umount map, then we've been
  92                  * expecting him to go down and we know ahead of time
  93                  * that recovery is not necessary. */
  94                 ocfs2_node_map_clear_bit(osb, &osb->umount_map, node_num);
  95                 return;
  96         }
  97
  98         ocfs2_recovery_thread(osb, node_num);
  99
 100         ocfs2_remove_node_from_vote_queues(osb, node_num);
 101 }
 102
 103 static void ocfs2_hb_node_down_cb(struct o2nm_node *node,
 104                                   int node_num,
 105                                   void *data)
 106 {
 107         ocfs2_do_node_down(node_num, (struct ocfs2_super *) data);
 108 }
 109
 110 /* Called from the dlm when it's about to evict a node. We may also
 111  * get a heartbeat callback later. */
 112 static void ocfs2_dlm_eviction_cb(int node_num,
 113                                   void *data)
 114 {
 115         struct ocfs2_super *osb = (struct ocfs2_super *) data;
 116         struct super_block *sb = osb->sb;
 117
 118         mlog(ML_NOTICE, "device (%u,%u): dlm has evicted node %d\n",
 119              MAJOR(sb->s_dev), MINOR(sb->s_dev), node_num);
 120
 121         ocfs2_do_node_down(node_num, osb);
 122 }
 123
 124 static void ocfs2_hb_node_up_cb(struct o2nm_node *node,
 125                                 int node_num,
 126                                 void *data)
 127 {
 128         struct ocfs2_super *osb = data;
 129
 130         BUG_ON(osb->node_num == node_num);
 131
 132         mlog(0, "node up event for %d\n", node_num);
 133         ocfs2_node_map_clear_bit(osb, &osb->umount_map, node_num);
 134 }
 135
 136 void ocfs2_setup_hb_callbacks(struct ocfs2_super *osb)
 137 {
 138         o2hb_setup_callback(&osb->osb_hb_down, O2HB_NODE_DOWN_CB,
 139                             ocfs2_hb_node_down_cb, osb,
 140                             OCFS2_HB_NODE_DOWN_PRI);
 141
 142         o2hb_setup_callback(&osb->osb_hb_up, O2HB_NODE_UP_CB,
 143                             ocfs2_hb_node_up_cb, osb, OCFS2_HB_NODE_UP_PRI);
 144
 145         /* Not exactly a heartbeat callback, but leads to essentially
 146          * the same path so we set it up here. */
 147         dlm_setup_eviction_cb(&osb->osb_eviction_cb,
 148                               ocfs2_dlm_eviction_cb,
 149                               osb);
 150 }
 151
 152 /* Most functions here are just stubs for now... */
 153 int ocfs2_register_hb_callbacks(struct ocfs2_super *osb)
 154 {
 155         int status;
 156
 157         if (ocfs2_mount_local(osb))
 158                 return 0;
 159
 160         status = o2hb_register_callback(&osb->osb_hb_down);
 161         if (status < 0) {
 162                 mlog_errno(status);
 163                 goto bail;
 164         }
 165
 166         status = o2hb_register_callback(&osb->osb_hb_up);
 167         if (status < 0) {
 168                 mlog_errno(status);
 169                 o2hb_unregister_callback(&osb->osb_hb_down);
 170         }
 171
 172 bail:
 173         return status;
 174 }
 175
 176 void ocfs2_clear_hb_callbacks(struct ocfs2_super *osb)
 177 {
 178         if (ocfs2_mount_local(osb))
 179                 return;
 180
 181         o2hb_unregister_callback(&osb->osb_hb_down);
 182         o2hb_unregister_callback(&osb->osb_hb_up);
 183 }
 184
 185 void ocfs2_stop_heartbeat(struct ocfs2_super *osb)
 186 {
 187         int ret;
 188         char *argv[5], *envp[3];
 189
 190         if (ocfs2_mount_local(osb))
 191                 return;
 192
 193         if (!osb->uuid_str) {
 194                 /* This can happen if we don't get far enough in mount... */
 195                 mlog(0, "No UUID with which to stop heartbeat!\n\n");
 196                 return;
 197         }
 198
 199         argv[0] = (char *)o2nm_get_hb_ctl_path();
 200         argv[1] = "-K";
 201         argv[2] = "-u";
 202         argv[3] = osb->uuid_str;
 203         argv[4] = NULL;
 204
 205         mlog(0, "Run: %s %s %s %s\n", argv[0], argv[1], argv[2], argv[3]);
 206
 207         /* minimal command environment taken from cpu_run_sbin_hotplug */
 208         envp[0] = "HOME=/";
 209         envp[1] = "PATH=/sbin:/bin:/usr/sbin:/usr/bin";
 210         envp[2] = NULL;
 211
 212         ret = call_usermodehelper(argv[0], argv, envp, 1);
 213         if (ret < 0)
 214                 mlog_errno(ret);
 215 }
 216
 217 /* special case -1 for now
 218  * TODO: should *really* make sure the calling func never passes -1!!  */
 219 void ocfs2_node_map_init(struct ocfs2_node_map *map)
 220 {
 221         map->num_nodes = OCFS2_NODE_MAP_MAX_NODES;
 222         memset(map->map, 0, BITS_TO_LONGS(OCFS2_NODE_MAP_MAX_NODES) *
 223                sizeof(unsigned long));
 224 }
 225
 226 static inline void __ocfs2_node_map_set_bit(struct ocfs2_node_map *map,
 227                                             int bit)
 228 {
 229         set_bit(bit, map->map);
 230 }
 231
 232 void ocfs2_node_map_set_bit(struct ocfs2_super *osb,
 233                             struct ocfs2_node_map *map,
 234                             int bit)
 235 {
 236         if (bit==-1)
 237                 return;
 238         BUG_ON(bit >= map->num_nodes);
 239         spin_lock(&osb->node_map_lock);
 240         __ocfs2_node_map_set_bit(map, bit);
 241         spin_unlock(&osb->node_map_lock);
 242 }
 243
 244 static inline void __ocfs2_node_map_clear_bit(struct ocfs2_node_map *map,
 245                                               int bit)
 246 {
 247         clear_bit(bit, map->map);
 248 }
 249
 250 void ocfs2_node_map_clear_bit(struct ocfs2_super *osb,
 251                               struct ocfs2_node_map *map,
 252                               int bit)
 253 {
 254         if (bit==-1)
 255                 return;
 256         BUG_ON(bit >= map->num_nodes);
 257         spin_lock(&osb->node_map_lock);
 258         __ocfs2_node_map_clear_bit(map, bit);
 259         spin_unlock(&osb->node_map_lock);
 260 }
 261
 262 int ocfs2_node_map_test_bit(struct ocfs2_super *osb,
 263                             struct ocfs2_node_map *map,
 264                             int bit)
 265 {
 266         int ret;
 267         if (bit >= map->num_nodes) {
 268                 mlog(ML_ERROR, "bit=%d map->num_nodes=%d\n", bit, map->num_nodes);
 269                 BUG();
 270         }
 271         spin_lock(&osb->node_map_lock);
 272         ret = test_bit(bit, map->map);
 273         spin_unlock(&osb->node_map_lock);
 274         return ret;
 275 }
 276
 277 static inline int __ocfs2_node_map_is_empty(struct ocfs2_node_map *map)
 278 {
 279         int bit;
 280         bit = find_next_bit(map->map, map->num_nodes, 0);
 281         if (bit < map->num_nodes)
 282                 return 0;
 283         return 1;
 284 }
 285
 286 int ocfs2_node_map_is_empty(struct ocfs2_super *osb,
 287                             struct ocfs2_node_map *map)
 288 {
 289         int ret;
 290         BUG_ON(map->num_nodes == 0);
 291         spin_lock(&osb->node_map_lock);
 292         ret = __ocfs2_node_map_is_empty(map);
 293         spin_unlock(&osb->node_map_lock);
 294         return ret;
 295 }
 296
 297 static void __ocfs2_node_map_dup(struct ocfs2_node_map *target,
 298                                  struct ocfs2_node_map *from)
 299 {
 300         BUG_ON(from->num_nodes == 0);
 301         ocfs2_node_map_init(target);
 302         __ocfs2_node_map_set(target, from);
 303 }
 304
 305 /* returns 1 if bit is the only bit set in target, 0 otherwise */
 306 int ocfs2_node_map_is_only(struct ocfs2_super *osb,
 307                            struct ocfs2_node_map *target,
 308                            int bit)
 309 {
 310         struct ocfs2_node_map temp;
 311         int ret;
 312
 313         spin_lock(&osb->node_map_lock);
 314         __ocfs2_node_map_dup(&temp, target);
 315         __ocfs2_node_map_clear_bit(&temp, bit);
 316         ret = __ocfs2_node_map_is_empty(&temp);
 317         spin_unlock(&osb->node_map_lock);
 318
 319         return ret;
 320 }
 321
 322 static void __ocfs2_node_map_set(struct ocfs2_node_map *target,
 323                                  struct ocfs2_node_map *from)
 324 {
 325         int num_longs, i;
 326
 327         BUG_ON(target->num_nodes != from->num_nodes);
 328         BUG_ON(target->num_nodes == 0);
 329
 330         num_longs = BITS_TO_LONGS(target->num_nodes);
 331         for (i = 0; i < num_longs; i++)
 332                 target->map[i] = from->map[i];
 333 }
 334
 335 /* Returns whether the recovery bit was actually set - it may not be
 336  * if a node is still marked as needing recovery */
 337 int ocfs2_recovery_map_set(struct ocfs2_super *osb,
 338                            int num)
 339 {
 340         int set = 0;
 341
 342         spin_lock(&osb->node_map_lock);
 343
 344         __ocfs2_node_map_clear_bit(&osb->mounted_map, num);
 345
 346         if (!test_bit(num, osb->recovery_map.map)) {
 347             __ocfs2_node_map_set_bit(&osb->recovery_map, num);
 348             set = 1;
 349         }
 350
 351         spin_unlock(&osb->node_map_lock);
 352
 353         return set;
 354 }
 355
 356 void ocfs2_recovery_map_clear(struct ocfs2_super *osb,
 357                               int num)
 358 {
 359         ocfs2_node_map_clear_bit(osb, &osb->recovery_map, num);
 360 }
 361
 362 int ocfs2_node_map_iterate(struct ocfs2_super *osb,
 363                            struct ocfs2_node_map *map,
 364                            int idx)
 365 {
 366         int i = idx;
 367
 368         idx = O2NM_INVALID_NODE_NUM;
 369         spin_lock(&osb->node_map_lock);
 370         if ((i != O2NM_INVALID_NODE_NUM) &&
 371             (i >= 0) &&
 372             (i < map->num_nodes)) {
 373                 while(i < map->num_nodes) {
 374                         if (test_bit(i, map->map)) {
 375                                 idx = i;
 376                                 break;
 377                         }
 378                         i++;
 379                 }
 380         }
 381         spin_unlock(&osb->node_map_lock);
 382         return idx;
 383 }