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 <dlm/dlmapi.h>
  34
  35 #define MLOG_MASK_PREFIX ML_SUPER
  36 #include <cluster/masklog.h>
  37
  38 #include "ocfs2.h"
  39
  40 #include "alloc.h"
  41 #include "heartbeat.h"
  42 #include "inode.h"
  43 #include "journal.h"
  44
  45 #include "buffer_head_io.h"
  46
  47 static inline void __ocfs2_node_map_set_bit(struct ocfs2_node_map *map,
  48                                             int bit);
  49 static inline void __ocfs2_node_map_clear_bit(struct ocfs2_node_map *map,
  50                                               int bit);
  51 static inline int __ocfs2_node_map_is_empty(struct ocfs2_node_map *map);
  52 static void __ocfs2_node_map_dup(struct ocfs2_node_map *target,
  53                                  struct ocfs2_node_map *from);
  54 static void __ocfs2_node_map_set(struct ocfs2_node_map *target,
  55                                  struct ocfs2_node_map *from);
  56
  57 void ocfs2_init_node_maps(struct ocfs2_super *osb)
  58 {
  59         spin_lock_init(&osb->node_map_lock);
  60         ocfs2_node_map_init(&osb->recovery_map);
  61         ocfs2_node_map_init(&osb->osb_recovering_orphan_dirs);
  62 }
  63
  64 static void ocfs2_do_node_down(int node_num,
  65                                struct ocfs2_super *osb)
  66 {
  67         BUG_ON(osb->node_num == node_num);
  68
  69         mlog(0, "ocfs2: node down event for %d\n", node_num);
  70
  71         if (!osb->dlm) {
  72                 /*
  73                  * No DLM means we're not even ready to participate yet.
  74                  * We check the slots after the DLM comes up, so we will
  75                  * notice the node death then.  We can safely ignore it
  76                  * here.
  77                  */
  78                 return;
  79         }
  80
  81         ocfs2_recovery_thread(osb, node_num);
  82 }
  83
  84 /* Called from the dlm when it's about to evict a node. We may also
  85  * get a heartbeat callback later. */
  86 static void ocfs2_dlm_eviction_cb(int node_num,
  87                                   void *data)
  88 {
  89         struct ocfs2_super *osb = (struct ocfs2_super *) data;
  90         struct super_block *sb = osb->sb;
  91
  92         mlog(ML_NOTICE, "device (%u,%u): dlm has evicted node %d\n",
  93              MAJOR(sb->s_dev), MINOR(sb->s_dev), node_num);
  94
  95         ocfs2_do_node_down(node_num, osb);
  96 }
  97
  98 void ocfs2_setup_hb_callbacks(struct ocfs2_super *osb)
  99 {
 100         /* Not exactly a heartbeat callback, but leads to essentially
 101          * the same path so we set it up here. */
 102         dlm_setup_eviction_cb(&osb->osb_eviction_cb,
 103                               ocfs2_dlm_eviction_cb,
 104                               osb);
 105 }
 106
 107 void ocfs2_stop_heartbeat(struct ocfs2_super *osb)
 108 {
 109         int ret;
 110         char *argv[5], *envp[3];
 111
 112         if (ocfs2_mount_local(osb))
 113                 return;
 114
 115         if (!osb->uuid_str) {
 116                 /* This can happen if we don't get far enough in mount... */
 117                 mlog(0, "No UUID with which to stop heartbeat!\n\n");
 118                 return;
 119         }
 120
 121         argv[0] = (char *)o2nm_get_hb_ctl_path();
 122         argv[1] = "-K";
 123         argv[2] = "-u";
 124         argv[3] = osb->uuid_str;
 125         argv[4] = NULL;
 126
 127         mlog(0, "Run: %s %s %s %s\n", argv[0], argv[1], argv[2], argv[3]);
 128
 129         /* minimal command environment taken from cpu_run_sbin_hotplug */
 130         envp[0] = "HOME=/";
 131         envp[1] = "PATH=/sbin:/bin:/usr/sbin:/usr/bin";
 132         envp[2] = NULL;
 133
 134         ret = call_usermodehelper(argv[0], argv, envp, UMH_WAIT_PROC);
 135         if (ret < 0)
 136                 mlog_errno(ret);
 137 }
 138
 139 /* special case -1 for now
 140  * TODO: should *really* make sure the calling func never passes -1!!  */
 141 void ocfs2_node_map_init(struct ocfs2_node_map *map)
 142 {
 143         map->num_nodes = OCFS2_NODE_MAP_MAX_NODES;
 144         memset(map->map, 0, BITS_TO_LONGS(OCFS2_NODE_MAP_MAX_NODES) *
 145                sizeof(unsigned long));
 146 }
 147
 148 static inline void __ocfs2_node_map_set_bit(struct ocfs2_node_map *map,
 149                                             int bit)
 150 {
 151         set_bit(bit, map->map);
 152 }
 153
 154 void ocfs2_node_map_set_bit(struct ocfs2_super *osb,
 155                             struct ocfs2_node_map *map,
 156                             int bit)
 157 {
 158         if (bit==-1)
 159                 return;
 160         BUG_ON(bit >= map->num_nodes);
 161         spin_lock(&osb->node_map_lock);
 162         __ocfs2_node_map_set_bit(map, bit);
 163         spin_unlock(&osb->node_map_lock);
 164 }
 165
 166 static inline void __ocfs2_node_map_clear_bit(struct ocfs2_node_map *map,
 167                                               int bit)
 168 {
 169         clear_bit(bit, map->map);
 170 }
 171
 172 void ocfs2_node_map_clear_bit(struct ocfs2_super *osb,
 173                               struct ocfs2_node_map *map,
 174                               int bit)
 175 {
 176         if (bit==-1)
 177                 return;
 178         BUG_ON(bit >= map->num_nodes);
 179         spin_lock(&osb->node_map_lock);
 180         __ocfs2_node_map_clear_bit(map, bit);
 181         spin_unlock(&osb->node_map_lock);
 182 }
 183
 184 int ocfs2_node_map_test_bit(struct ocfs2_super *osb,
 185                             struct ocfs2_node_map *map,
 186                             int bit)
 187 {
 188         int ret;
 189         if (bit >= map->num_nodes) {
 190                 mlog(ML_ERROR, "bit=%d map->num_nodes=%d\n", bit, map->num_nodes);
 191                 BUG();
 192         }
 193         spin_lock(&osb->node_map_lock);
 194         ret = test_bit(bit, map->map);
 195         spin_unlock(&osb->node_map_lock);
 196         return ret;
 197 }
 198
 199 static inline int __ocfs2_node_map_is_empty(struct ocfs2_node_map *map)
 200 {
 201         int bit;
 202         bit = find_next_bit(map->map, map->num_nodes, 0);
 203         if (bit < map->num_nodes)
 204                 return 0;
 205         return 1;
 206 }
 207
 208 int ocfs2_node_map_is_empty(struct ocfs2_super *osb,
 209                             struct ocfs2_node_map *map)
 210 {
 211         int ret;
 212         BUG_ON(map->num_nodes == 0);
 213         spin_lock(&osb->node_map_lock);
 214         ret = __ocfs2_node_map_is_empty(map);
 215         spin_unlock(&osb->node_map_lock);
 216         return ret;
 217 }
 218
 219 static void __ocfs2_node_map_dup(struct ocfs2_node_map *target,
 220                                  struct ocfs2_node_map *from)
 221 {
 222         BUG_ON(from->num_nodes == 0);
 223         ocfs2_node_map_init(target);
 224         __ocfs2_node_map_set(target, from);
 225 }
 226
 227 /* returns 1 if bit is the only bit set in target, 0 otherwise */
 228 int ocfs2_node_map_is_only(struct ocfs2_super *osb,
 229                            struct ocfs2_node_map *target,
 230                            int bit)
 231 {
 232         struct ocfs2_node_map temp;
 233         int ret;
 234
 235         spin_lock(&osb->node_map_lock);
 236         __ocfs2_node_map_dup(&temp, target);
 237         __ocfs2_node_map_clear_bit(&temp, bit);
 238         ret = __ocfs2_node_map_is_empty(&temp);
 239         spin_unlock(&osb->node_map_lock);
 240
 241         return ret;
 242 }
 243
 244 static void __ocfs2_node_map_set(struct ocfs2_node_map *target,
 245                                  struct ocfs2_node_map *from)
 246 {
 247         int num_longs, i;
 248
 249         BUG_ON(target->num_nodes != from->num_nodes);
 250         BUG_ON(target->num_nodes == 0);
 251
 252         num_longs = BITS_TO_LONGS(target->num_nodes);
 253         for (i = 0; i < num_longs; i++)
 254                 target->map[i] = from->map[i];
 255 }
 256
 257 /* Returns whether the recovery bit was actually set - it may not be
 258  * if a node is still marked as needing recovery */
 259 int ocfs2_recovery_map_set(struct ocfs2_super *osb,
 260                            int num)
 261 {
 262         int set = 0;
 263
 264         spin_lock(&osb->node_map_lock);
 265
 266         if (!test_bit(num, osb->recovery_map.map)) {
 267             __ocfs2_node_map_set_bit(&osb->recovery_map, num);
 268             set = 1;
 269         }
 270
 271         spin_unlock(&osb->node_map_lock);
 272
 273         return set;
 274 }
 275
 276 void ocfs2_recovery_map_clear(struct ocfs2_super *osb,
 277                               int num)
 278 {
 279         ocfs2_node_map_clear_bit(osb, &osb->recovery_map, num);
 280 }
 281
 282 int ocfs2_node_map_iterate(struct ocfs2_super *osb,
 283                            struct ocfs2_node_map *map,
 284                            int idx)
 285 {
 286         int i = idx;
 287
 288         idx = O2NM_INVALID_NODE_NUM;
 289         spin_lock(&osb->node_map_lock);
 290         if ((i != O2NM_INVALID_NODE_NUM) &&
 291             (i >= 0) &&
 292             (i < map->num_nodes)) {
 293                 while(i < map->num_nodes) {
 294                         if (test_bit(i, map->map)) {
 295                                 idx = i;
 296                                 break;
 297                         }
 298                         i++;
 299                 }
 300         }
 301         spin_unlock(&osb->node_map_lock);
 302         return idx;
 303 }