1 /* -*- mode: c; c-basic-offset: 8; -*- 2 * vim: noexpandtab sw=8 ts=8 sts=0: 3 * 4 * slot_map.c 5 * 6 * 7 * 8 * Copyright (C) 2002, 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 #include <linux/types.h> 27 #include <linux/slab.h> 28 #include <linux/highmem.h> 29 30 #define MLOG_MASK_PREFIX ML_SUPER 31 #include <cluster/masklog.h> 32 33 #include "ocfs2.h" 34 35 #include "dlmglue.h" 36 #include "extent_map.h" 37 #include "heartbeat.h" 38 #include "inode.h" 39 #include "slot_map.h" 40 #include "super.h" 41 #include "sysfile.h" 42 43 #include "buffer_head_io.h" 44 45 static s16 __ocfs2_node_num_to_slot(struct ocfs2_slot_info *si, 46 s16 global); 47 static void __ocfs2_fill_slot(struct ocfs2_slot_info *si, 48 s16 slot_num, 49 s16 node_num); 50 51 /* Use the slot information we've collected to create a map of mounted 52 * nodes. Should be holding an EX on super block. assumes slot info is 53 * up to date. Note that we call this *after* we find a slot, so our 54 * own node should be set in the map too... */ 55 void ocfs2_populate_mounted_map(struct ocfs2_super *osb) 56 { 57 int i; 58 struct ocfs2_slot_info *si = osb->slot_info; 59 60 spin_lock(&si->si_lock); 61 62 for (i = 0; i < si->si_size; i++) 63 if (si->si_global_node_nums[i] != OCFS2_INVALID_SLOT) 64 ocfs2_node_map_set_bit(osb, &osb->mounted_map, 65 si->si_global_node_nums[i]); 66 67 spin_unlock(&si->si_lock); 68 } 69 70 /* post the slot information on disk into our slot_info struct. */ 71 void ocfs2_update_slot_info(struct ocfs2_slot_info *si) 72 { 73 int i; 74 __le16 *disk_info; 75 76 /* we don't read the slot block here as ocfs2_super_lock 77 * should've made sure we have the most recent copy. */ 78 spin_lock(&si->si_lock); 79 disk_info = (__le16 *) si->si_bh->b_data; 80 81 for (i = 0; i < si->si_size; i++) 82 si->si_global_node_nums[i] = le16_to_cpu(disk_info[i]); 83 84 spin_unlock(&si->si_lock); 85 } 86 87 /* post the our slot info stuff into it's destination bh and write it 88 * out. */ 89 int ocfs2_update_disk_slots(struct ocfs2_super *osb, 90 struct ocfs2_slot_info *si) 91 { 92 int status, i; 93 __le16 *disk_info = (__le16 *) si->si_bh->b_data; 94 95 spin_lock(&si->si_lock); 96 for (i = 0; i < si->si_size; i++) 97 disk_info[i] = cpu_to_le16(si->si_global_node_nums[i]); 98 spin_unlock(&si->si_lock); 99 100 status = ocfs2_write_block(osb, si->si_bh, si->si_inode); 101 if (status < 0) 102 mlog_errno(status); 103 104 return status; 105 } 106 107 /* try to find global node in the slot info. Returns 108 * OCFS2_INVALID_SLOT if nothing is found. */ 109 static s16 __ocfs2_node_num_to_slot(struct ocfs2_slot_info *si, 110 s16 global) 111 { 112 int i; 113 s16 ret = OCFS2_INVALID_SLOT; 114 115 for(i = 0; i < si->si_num_slots; i++) { 116 if (global == si->si_global_node_nums[i]) { 117 ret = (s16) i; 118 break; 119 } 120 } 121 return ret; 122 } 123 124 static s16 __ocfs2_find_empty_slot(struct ocfs2_slot_info *si) 125 { 126 int i; 127 s16 ret = OCFS2_INVALID_SLOT; 128 129 for(i = 0; i < si->si_num_slots; i++) { 130 if (OCFS2_INVALID_SLOT == si->si_global_node_nums[i]) { 131 ret = (s16) i; 132 break; 133 } 134 } 135 return ret; 136 } 137 138 s16 ocfs2_node_num_to_slot(struct ocfs2_slot_info *si, 139 s16 global) 140 { 141 s16 ret; 142 143 spin_lock(&si->si_lock); 144 ret = __ocfs2_node_num_to_slot(si, global); 145 spin_unlock(&si->si_lock); 146 return ret; 147 } 148 149 static void __ocfs2_fill_slot(struct ocfs2_slot_info *si, 150 s16 slot_num, 151 s16 node_num) 152 { 153 BUG_ON(slot_num == OCFS2_INVALID_SLOT); 154 BUG_ON(slot_num >= si->si_num_slots); 155 BUG_ON((node_num != O2NM_INVALID_NODE_NUM) && 156 (node_num >= O2NM_MAX_NODES)); 157 158 si->si_global_node_nums[slot_num] = node_num; 159 } 160 161 void ocfs2_clear_slot(struct ocfs2_slot_info *si, 162 s16 slot_num) 163 { 164 spin_lock(&si->si_lock); 165 __ocfs2_fill_slot(si, slot_num, OCFS2_INVALID_SLOT); 166 spin_unlock(&si->si_lock); 167 } 168 169 int ocfs2_init_slot_info(struct ocfs2_super *osb) 170 { 171 int status, i; 172 u64 blkno; 173 struct inode *inode = NULL; 174 struct buffer_head *bh = NULL; 175 struct ocfs2_slot_info *si; 176 177 si = kzalloc(sizeof(struct ocfs2_slot_info), GFP_KERNEL); 178 if (!si) { 179 status = -ENOMEM; 180 mlog_errno(status); 181 goto bail; 182 } 183 184 spin_lock_init(&si->si_lock); 185 si->si_num_slots = osb->max_slots; 186 si->si_size = OCFS2_MAX_SLOTS; 187 188 for(i = 0; i < si->si_num_slots; i++) 189 si->si_global_node_nums[i] = OCFS2_INVALID_SLOT; 190 191 inode = ocfs2_get_system_file_inode(osb, SLOT_MAP_SYSTEM_INODE, 192 OCFS2_INVALID_SLOT); 193 if (!inode) { 194 status = -EINVAL; 195 mlog_errno(status); 196 goto bail; 197 } 198 199 status = ocfs2_extent_map_get_blocks(inode, 0ULL, &blkno, NULL, NULL); 200 if (status < 0) { 201 mlog_errno(status); 202 goto bail; 203 } 204 205 status = ocfs2_read_block(osb, blkno, &bh, 0, inode); 206 if (status < 0) { 207 mlog_errno(status); 208 goto bail; 209 } 210 211 si->si_inode = inode; 212 si->si_bh = bh; 213 osb->slot_info = si; 214 bail: 215 if (status < 0 && si) 216 ocfs2_free_slot_info(si); 217 218 return status; 219 } 220 221 void ocfs2_free_slot_info(struct ocfs2_slot_info *si) 222 { 223 if (si->si_inode) 224 iput(si->si_inode); 225 if (si->si_bh) 226 brelse(si->si_bh); 227 kfree(si); 228 } 229 230 int ocfs2_find_slot(struct ocfs2_super *osb) 231 { 232 int status; 233 s16 slot; 234 struct ocfs2_slot_info *si; 235 236 mlog_entry_void(); 237 238 si = osb->slot_info; 239 240 ocfs2_update_slot_info(si); 241 242 spin_lock(&si->si_lock); 243 /* search for ourselves first and take the slot if it already 244 * exists. Perhaps we need to mark this in a variable for our 245 * own journal recovery? Possibly not, though we certainly 246 * need to warn to the user */ 247 slot = __ocfs2_node_num_to_slot(si, osb->node_num); 248 if (slot == OCFS2_INVALID_SLOT) { 249 /* if no slot yet, then just take 1st available 250 * one. */ 251 slot = __ocfs2_find_empty_slot(si); 252 if (slot == OCFS2_INVALID_SLOT) { 253 spin_unlock(&si->si_lock); 254 mlog(ML_ERROR, "no free slots available!\n"); 255 status = -EINVAL; 256 goto bail; 257 } 258 } else 259 mlog(ML_NOTICE, "slot %d is already allocated to this node!\n", 260 slot); 261 262 __ocfs2_fill_slot(si, slot, osb->node_num); 263 osb->slot_num = slot; 264 spin_unlock(&si->si_lock); 265 266 mlog(0, "taking node slot %d\n", osb->slot_num); 267 268 status = ocfs2_update_disk_slots(osb, si); 269 if (status < 0) 270 mlog_errno(status); 271 272 bail: 273 mlog_exit(status); 274 return status; 275 } 276 277 void ocfs2_put_slot(struct ocfs2_super *osb) 278 { 279 int status; 280 struct ocfs2_slot_info *si = osb->slot_info; 281 282 if (!si) 283 return; 284 285 ocfs2_update_slot_info(si); 286 287 spin_lock(&si->si_lock); 288 __ocfs2_fill_slot(si, osb->slot_num, OCFS2_INVALID_SLOT); 289 osb->slot_num = OCFS2_INVALID_SLOT; 290 spin_unlock(&si->si_lock); 291 292 status = ocfs2_update_disk_slots(osb, si); 293 if (status < 0) { 294 mlog_errno(status); 295 goto bail; 296 } 297 298 bail: 299 osb->slot_info = NULL; 300 ocfs2_free_slot_info(si); 301 } 302 303