fs/ocfs2/resize.c

   1 /* -*- mode: c; c-basic-offset: 8; -*-
   2  * vim: noexpandtab sw=8 ts=8 sts=0:
   3  *
   4  * resize.c
   5  *
   6  * volume resize.
   7  * Inspired by ext3/resize.c.
   8  *
   9  * Copyright (C) 2007 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
  30 #include <cluster/masklog.h>
  31
  32 #include "ocfs2.h"
  33
  34 #include "alloc.h"
  35 #include "dlmglue.h"
  36 #include "inode.h"
  37 #include "journal.h"
  38 #include "super.h"
  39 #include "sysfile.h"
  40 #include "uptodate.h"
  41 #include "ocfs2_trace.h"
  42
  43 #include "buffer_head_io.h"
  44 #include "suballoc.h"
  45 #include "resize.h"
  46
  47 /*
  48  * Check whether there are new backup superblocks exist
  49  * in the last group. If there are some, mark them or clear
  50  * them in the bitmap.
  51  *
  52  * Return how many backups we find in the last group.
  53  */
  54 static u16 ocfs2_calc_new_backup_super(struct inode *inode,
  55                                        struct ocfs2_group_desc *gd,
  56                                        u16 cl_cpg,
  57                                        int set)
  58 {
  59         int i;
  60         u16 backups = 0;
  61         u32 cluster;
  62         u64 blkno, gd_blkno, lgd_blkno = le64_to_cpu(gd->bg_blkno);
  63
  64         for (i = 0; i < OCFS2_MAX_BACKUP_SUPERBLOCKS; i++) {
  65                 blkno = ocfs2_backup_super_blkno(inode->i_sb, i);
  66                 cluster = ocfs2_blocks_to_clusters(inode->i_sb, blkno);
  67
  68                 gd_blkno = ocfs2_which_cluster_group(inode, cluster);
  69                 if (gd_blkno < lgd_blkno)
  70                         continue;
  71                 else if (gd_blkno > lgd_blkno)
  72                         break;
  73
  74                 if (set)
  75                         ocfs2_set_bit(cluster % cl_cpg,
  76                                       (unsigned long *)gd->bg_bitmap);
  77                 else
  78                         ocfs2_clear_bit(cluster % cl_cpg,
  79                                         (unsigned long *)gd->bg_bitmap);
  80                 backups++;
  81         }
  82
  83         return backups;
  84 }
  85
  86 static int ocfs2_update_last_group_and_inode(handle_t *handle,
  87                                              struct inode *bm_inode,
  88                                              struct buffer_head *bm_bh,
  89                                              struct buffer_head *group_bh,
  90                                              u32 first_new_cluster,
  91                                              int new_clusters)
  92 {
  93         int ret = 0;
  94         struct ocfs2_super *osb = OCFS2_SB(bm_inode->i_sb);
  95         struct ocfs2_dinode *fe = (struct ocfs2_dinode *) bm_bh->b_data;
  96         struct ocfs2_chain_list *cl = &fe->id2.i_chain;
  97         struct ocfs2_chain_rec *cr;
  98         struct ocfs2_group_desc *group;
  99         u16 chain, num_bits, backups = 0;
 100         u16 cl_bpc = le16_to_cpu(cl->cl_bpc);
 101         u16 cl_cpg = le16_to_cpu(cl->cl_cpg);
 102
 103         trace_ocfs2_update_last_group_and_inode(new_clusters,
 104                                                 first_new_cluster);
 105
 106         ret = ocfs2_journal_access_gd(handle, INODE_CACHE(bm_inode),
 107                                       group_bh, OCFS2_JOURNAL_ACCESS_WRITE);
 108         if (ret < 0) {
 109                 mlog_errno(ret);
 110                 goto out;
 111         }
 112
 113         group = (struct ocfs2_group_desc *)group_bh->b_data;
 114
 115         /* update the group first. */
 116         num_bits = new_clusters * cl_bpc;
 117         le16_add_cpu(&group->bg_bits, num_bits);
 118         le16_add_cpu(&group->bg_free_bits_count, num_bits);
 119
 120         /*
 121          * check whether there are some new backup superblocks exist in
 122          * this group and update the group bitmap accordingly.
 123          */
 124         if (OCFS2_HAS_COMPAT_FEATURE(osb->sb,
 125                                      OCFS2_FEATURE_COMPAT_BACKUP_SB)) {
 126                 backups = ocfs2_calc_new_backup_super(bm_inode,
 127                                                      group,
 128                                                      cl_cpg, 1);
 129                 le16_add_cpu(&group->bg_free_bits_count, -1 * backups);
 130         }
 131
 132         ocfs2_journal_dirty(handle, group_bh);
 133
 134         /* update the inode accordingly. */
 135         ret = ocfs2_journal_access_di(handle, INODE_CACHE(bm_inode), bm_bh,
 136                                       OCFS2_JOURNAL_ACCESS_WRITE);
 137         if (ret < 0) {
 138                 mlog_errno(ret);
 139                 goto out_rollback;
 140         }
 141
 142         chain = le16_to_cpu(group->bg_chain);
 143         cr = (&cl->cl_recs[chain]);
 144         le32_add_cpu(&cr->c_total, num_bits);
 145         le32_add_cpu(&cr->c_free, num_bits);
 146         le32_add_cpu(&fe->id1.bitmap1.i_total, num_bits);
 147         le32_add_cpu(&fe->i_clusters, new_clusters);
 148
 149         if (backups) {
 150                 le32_add_cpu(&cr->c_free, -1 * backups);
 151                 le32_add_cpu(&fe->id1.bitmap1.i_used, backups);
 152         }
 153
 154         spin_lock(&OCFS2_I(bm_inode)->ip_lock);
 155         OCFS2_I(bm_inode)->ip_clusters = le32_to_cpu(fe->i_clusters);
 156         le64_add_cpu(&fe->i_size, (u64)new_clusters << osb->s_clustersize_bits);
 157         spin_unlock(&OCFS2_I(bm_inode)->ip_lock);
 158         i_size_write(bm_inode, le64_to_cpu(fe->i_size));
 159
 160         ocfs2_journal_dirty(handle, bm_bh);
 161
 162 out_rollback:
 163         if (ret < 0) {
 164                 ocfs2_calc_new_backup_super(bm_inode,
 165                                             group,
 166                                             cl_cpg, 0);
 167                 le16_add_cpu(&group->bg_free_bits_count, backups);
 168                 le16_add_cpu(&group->bg_bits, -1 * num_bits);
 169                 le16_add_cpu(&group->bg_free_bits_count, -1 * num_bits);
 170         }
 171 out:
 172         if (ret)
 173                 mlog_errno(ret);
 174         return ret;
 175 }
 176
 177 static int update_backups(struct inode * inode, u32 clusters, char *data)
 178 {
 179         int i, ret = 0;
 180         u32 cluster;
 181         u64 blkno;
 182         struct buffer_head *backup = NULL;
 183         struct ocfs2_dinode *backup_di = NULL;
 184         struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
 185
 186         /* calculate the real backups we need to update. */
 187         for (i = 0; i < OCFS2_MAX_BACKUP_SUPERBLOCKS; i++) {
 188                 blkno = ocfs2_backup_super_blkno(inode->i_sb, i);
 189                 cluster = ocfs2_blocks_to_clusters(inode->i_sb, blkno);
 190                 if (cluster > clusters)
 191                         break;
 192
 193                 ret = ocfs2_read_blocks_sync(osb, blkno, 1, &backup);
 194                 if (ret < 0) {
 195                         mlog_errno(ret);
 196                         break;
 197                 }
 198
 199                 memcpy(backup->b_data, data, inode->i_sb->s_blocksize);
 200
 201                 backup_di = (struct ocfs2_dinode *)backup->b_data;
 202                 backup_di->i_blkno = cpu_to_le64(blkno);
 203
 204                 ret = ocfs2_write_super_or_backup(osb, backup);
 205                 brelse(backup);
 206                 backup = NULL;
 207                 if (ret < 0) {
 208                         mlog_errno(ret);
 209                         break;
 210                 }
 211         }
 212
 213         return ret;
 214 }
 215
 216 static void ocfs2_update_super_and_backups(struct inode *inode,
 217                                            int new_clusters)
 218 {
 219         int ret;
 220         u32 clusters = 0;
 221         struct buffer_head *super_bh = NULL;
 222         struct ocfs2_dinode *super_di = NULL;
 223         struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
 224
 225         /*
 226          * update the superblock last.
 227          * It doesn't matter if the write failed.
 228          */
 229         ret = ocfs2_read_blocks_sync(osb, OCFS2_SUPER_BLOCK_BLKNO, 1,
 230                                      &super_bh);
 231         if (ret < 0) {
 232                 mlog_errno(ret);
 233                 goto out;
 234         }
 235
 236         super_di = (struct ocfs2_dinode *)super_bh->b_data;
 237         le32_add_cpu(&super_di->i_clusters, new_clusters);
 238         clusters = le32_to_cpu(super_di->i_clusters);
 239
 240         ret = ocfs2_write_super_or_backup(osb, super_bh);
 241         if (ret < 0) {
 242                 mlog_errno(ret);
 243                 goto out;
 244         }
 245
 246         if (OCFS2_HAS_COMPAT_FEATURE(osb->sb, OCFS2_FEATURE_COMPAT_BACKUP_SB))
 247                 ret = update_backups(inode, clusters, super_bh->b_data);
 248
 249 out:
 250         brelse(super_bh);
 251         if (ret)
 252                 printk(KERN_WARNING "ocfs2: Failed to update super blocks on %s"
 253                         " during fs resize. This condition is not fatal,"
 254                         " but fsck.ocfs2 should be run to fix it\n",
 255                         osb->dev_str);
 256         return;
 257 }
 258
 259 /*
 260  * Extend the filesystem to the new number of clusters specified.  This entry
 261  * point is only used to extend the current filesystem to the end of the last
 262  * existing group.
 263  */
 264 int ocfs2_group_extend(struct inode * inode, int new_clusters)
 265 {
 266         int ret;
 267         handle_t *handle;
 268         struct buffer_head *main_bm_bh = NULL;
 269         struct buffer_head *group_bh = NULL;
 270         struct inode *main_bm_inode = NULL;
 271         struct ocfs2_dinode *fe = NULL;
 272         struct ocfs2_group_desc *group = NULL;
 273         struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
 274         u16 cl_bpc;
 275         u32 first_new_cluster;
 276         u64 lgd_blkno;
 277
 278         if (ocfs2_is_hard_readonly(osb) || ocfs2_is_soft_readonly(osb))
 279                 return -EROFS;
 280
 281         if (new_clusters < 0)
 282                 return -EINVAL;
 283         else if (new_clusters == 0)
 284                 return 0;
 285
 286         main_bm_inode = ocfs2_get_system_file_inode(osb,
 287                                                     GLOBAL_BITMAP_SYSTEM_INODE,
 288                                                     OCFS2_INVALID_SLOT);
 289         if (!main_bm_inode) {
 290                 ret = -EINVAL;
 291                 mlog_errno(ret);
 292                 goto out;
 293         }
 294
 295         mutex_lock(&main_bm_inode->i_mutex);
 296
 297         ret = ocfs2_inode_lock(main_bm_inode, &main_bm_bh, 1);
 298         if (ret < 0) {
 299                 mlog_errno(ret);
 300                 goto out_mutex;
 301         }
 302
 303         fe = (struct ocfs2_dinode *)main_bm_bh->b_data;
 304
 305         /* main_bm_bh is validated by inode read inside ocfs2_inode_lock(),
 306          * so any corruption is a code bug. */
 307         BUG_ON(!OCFS2_IS_VALID_DINODE(fe));
 308
 309         if (le16_to_cpu(fe->id2.i_chain.cl_cpg) !=
 310                 ocfs2_group_bitmap_size(osb->sb, 0,
 311                                         osb->s_feature_incompat) * 8) {
 312                 mlog(ML_ERROR, "The disk is too old and small. "
 313                      "Force to do offline resize.");
 314                 ret = -EINVAL;
 315                 goto out_unlock;
 316         }
 317
 318         first_new_cluster = le32_to_cpu(fe->i_clusters);
 319         lgd_blkno = ocfs2_which_cluster_group(main_bm_inode,
 320                                               first_new_cluster - 1);
 321
 322         ret = ocfs2_read_group_descriptor(main_bm_inode, fe, lgd_blkno,
 323                                           &group_bh);
 324         if (ret < 0) {
 325                 mlog_errno(ret);
 326                 goto out_unlock;
 327         }
 328         group = (struct ocfs2_group_desc *)group_bh->b_data;
 329
 330         cl_bpc = le16_to_cpu(fe->id2.i_chain.cl_bpc);
 331         if (le16_to_cpu(group->bg_bits) / cl_bpc + new_clusters >
 332                 le16_to_cpu(fe->id2.i_chain.cl_cpg)) {
 333                 ret = -EINVAL;
 334                 goto out_unlock;
 335         }
 336
 337
 338         trace_ocfs2_group_extend(
 339              (unsigned long long)le64_to_cpu(group->bg_blkno), new_clusters);
 340
 341         handle = ocfs2_start_trans(osb, OCFS2_GROUP_EXTEND_CREDITS);
 342         if (IS_ERR(handle)) {
 343                 mlog_errno(PTR_ERR(handle));
 344                 ret = -EINVAL;
 345                 goto out_unlock;
 346         }
 347
 348         /* update the last group descriptor and inode. */
 349         ret = ocfs2_update_last_group_and_inode(handle, main_bm_inode,
 350                                                 main_bm_bh, group_bh,
 351                                                 first_new_cluster,
 352                                                 new_clusters);
 353         if (ret) {
 354                 mlog_errno(ret);
 355                 goto out_commit;
 356         }
 357
 358         ocfs2_update_super_and_backups(main_bm_inode, new_clusters);
 359
 360 out_commit:
 361         ocfs2_commit_trans(osb, handle);
 362 out_unlock:
 363         brelse(group_bh);
 364         brelse(main_bm_bh);
 365
 366         ocfs2_inode_unlock(main_bm_inode, 1);
 367
 368 out_mutex:
 369         mutex_unlock(&main_bm_inode->i_mutex);
 370         iput(main_bm_inode);
 371
 372 out:
 373         return ret;
 374 }
 375
 376 static int ocfs2_check_new_group(struct inode *inode,
 377                                  struct ocfs2_dinode *di,
 378                                  struct ocfs2_new_group_input *input,
 379                                  struct buffer_head *group_bh)
 380 {
 381         int ret;
 382         struct ocfs2_group_desc *gd =
 383                 (struct ocfs2_group_desc *)group_bh->b_data;
 384         u16 cl_bpc = le16_to_cpu(di->id2.i_chain.cl_bpc);
 385
 386         ret = ocfs2_check_group_descriptor(inode->i_sb, di, group_bh);
 387         if (ret)
 388                 goto out;
 389
 390         ret = -EINVAL;
 391         if (le16_to_cpu(gd->bg_chain) != input->chain)
 392                 mlog(ML_ERROR, "Group descriptor # %llu has bad chain %u "
 393                      "while input has %u set.\n",
 394                      (unsigned long long)le64_to_cpu(gd->bg_blkno),
 395                      le16_to_cpu(gd->bg_chain), input->chain);
 396         else if (le16_to_cpu(gd->bg_bits) != input->clusters * cl_bpc)
 397                 mlog(ML_ERROR, "Group descriptor # %llu has bit count %u but "
 398                      "input has %u clusters set\n",
 399                      (unsigned long long)le64_to_cpu(gd->bg_blkno),
 400                      le16_to_cpu(gd->bg_bits), input->clusters);
 401         else if (le16_to_cpu(gd->bg_free_bits_count) != input->frees * cl_bpc)
 402                 mlog(ML_ERROR, "Group descriptor # %llu has free bit count %u "
 403                      "but it should have %u set\n",
 404                      (unsigned long long)le64_to_cpu(gd->bg_blkno),
 405                      le16_to_cpu(gd->bg_bits),
 406                      input->frees * cl_bpc);
 407         else
 408                 ret = 0;
 409
 410 out:
 411         return ret;
 412 }
 413
 414 static int ocfs2_verify_group_and_input(struct inode *inode,
 415                                         struct ocfs2_dinode *di,
 416                                         struct ocfs2_new_group_input *input,
 417                                         struct buffer_head *group_bh)
 418 {
 419         u16 cl_count = le16_to_cpu(di->id2.i_chain.cl_count);
 420         u16 cl_cpg = le16_to_cpu(di->id2.i_chain.cl_cpg);
 421         u16 next_free = le16_to_cpu(di->id2.i_chain.cl_next_free_rec);
 422         u32 cluster = ocfs2_blocks_to_clusters(inode->i_sb, input->group);
 423         u32 total_clusters = le32_to_cpu(di->i_clusters);
 424         int ret = -EINVAL;
 425
 426         if (cluster < total_clusters)
 427                 mlog(ML_ERROR, "add a group which is in the current volume.\n");
 428         else if (input->chain >= cl_count)
 429                 mlog(ML_ERROR, "input chain exceeds the limit.\n");
 430         else if (next_free != cl_count && next_free != input->chain)
 431                 mlog(ML_ERROR,
 432                      "the add group should be in chain %u\n", next_free);
 433         else if (total_clusters + input->clusters < total_clusters)
 434                 mlog(ML_ERROR, "add group's clusters overflow.\n");
 435         else if (input->clusters > cl_cpg)
 436                 mlog(ML_ERROR, "the cluster exceeds the maximum of a group\n");
 437         else if (input->frees > input->clusters)
 438                 mlog(ML_ERROR, "the free cluster exceeds the total clusters\n");
 439         else if (total_clusters % cl_cpg != 0)
 440                 mlog(ML_ERROR,
 441                      "the last group isn't full. Use group extend first.\n");
 442         else if (input->group != ocfs2_which_cluster_group(inode, cluster))
 443                 mlog(ML_ERROR, "group blkno is invalid\n");
 444         else if ((ret = ocfs2_check_new_group(inode, di, input, group_bh)))
 445                 mlog(ML_ERROR, "group descriptor check failed.\n");
 446         else
 447                 ret = 0;
 448
 449         return ret;
 450 }
 451
 452 /* Add a new group descriptor to global_bitmap. */
 453 int ocfs2_group_add(struct inode *inode, struct ocfs2_new_group_input *input)
 454 {
 455         int ret;
 456         handle_t *handle;
 457         struct buffer_head *main_bm_bh = NULL;
 458         struct inode *main_bm_inode = NULL;
 459         struct ocfs2_dinode *fe = NULL;
 460         struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
 461         struct buffer_head *group_bh = NULL;
 462         struct ocfs2_group_desc *group = NULL;
 463         struct ocfs2_chain_list *cl;
 464         struct ocfs2_chain_rec *cr;
 465         u16 cl_bpc;
 466         u64 bg_ptr;
 467
 468         if (ocfs2_is_hard_readonly(osb) || ocfs2_is_soft_readonly(osb))
 469                 return -EROFS;
 470
 471         main_bm_inode = ocfs2_get_system_file_inode(osb,
 472                                                     GLOBAL_BITMAP_SYSTEM_INODE,
 473                                                     OCFS2_INVALID_SLOT);
 474         if (!main_bm_inode) {
 475                 ret = -EINVAL;
 476                 mlog_errno(ret);
 477                 goto out;
 478         }
 479
 480         mutex_lock(&main_bm_inode->i_mutex);
 481
 482         ret = ocfs2_inode_lock(main_bm_inode, &main_bm_bh, 1);
 483         if (ret < 0) {
 484                 mlog_errno(ret);
 485                 goto out_mutex;
 486         }
 487
 488         fe = (struct ocfs2_dinode *)main_bm_bh->b_data;
 489
 490         if (le16_to_cpu(fe->id2.i_chain.cl_cpg) !=
 491                 ocfs2_group_bitmap_size(osb->sb, 0,
 492                                         osb->s_feature_incompat) * 8) {
 493                 mlog(ML_ERROR, "The disk is too old and small."
 494                      " Force to do offline resize.");
 495                 ret = -EINVAL;
 496                 goto out_unlock;
 497         }
 498
 499         ret = ocfs2_read_blocks_sync(osb, input->group, 1, &group_bh);
 500         if (ret < 0) {
 501                 mlog(ML_ERROR, "Can't read the group descriptor # %llu "
 502                      "from the device.", (unsigned long long)input->group);
 503                 goto out_unlock;
 504         }
 505
 506         ocfs2_set_new_buffer_uptodate(INODE_CACHE(inode), group_bh);
 507
 508         ret = ocfs2_verify_group_and_input(main_bm_inode, fe, input, group_bh);
 509         if (ret) {
 510                 mlog_errno(ret);
 511                 goto out_free_group_bh;
 512         }
 513
 514         trace_ocfs2_group_add((unsigned long long)input->group,
 515                                input->chain, input->clusters, input->frees);
 516
 517         handle = ocfs2_start_trans(osb, OCFS2_GROUP_ADD_CREDITS);
 518         if (IS_ERR(handle)) {
 519                 mlog_errno(PTR_ERR(handle));
 520                 ret = -EINVAL;
 521                 goto out_free_group_bh;
 522         }
 523
 524         cl_bpc = le16_to_cpu(fe->id2.i_chain.cl_bpc);
 525         cl = &fe->id2.i_chain;
 526         cr = &cl->cl_recs[input->chain];
 527
 528         ret = ocfs2_journal_access_gd(handle, INODE_CACHE(main_bm_inode),
 529                                       group_bh, OCFS2_JOURNAL_ACCESS_WRITE);
 530         if (ret < 0) {
 531                 mlog_errno(ret);
 532                 goto out_commit;
 533         }
 534
 535         group = (struct ocfs2_group_desc *)group_bh->b_data;
 536         bg_ptr = le64_to_cpu(group->bg_next_group);
 537         group->bg_next_group = cr->c_blkno;
 538         ocfs2_journal_dirty(handle, group_bh);
 539
 540         ret = ocfs2_journal_access_di(handle, INODE_CACHE(main_bm_inode),
 541                                       main_bm_bh, OCFS2_JOURNAL_ACCESS_WRITE);
 542         if (ret < 0) {
 543                 group->bg_next_group = cpu_to_le64(bg_ptr);
 544                 mlog_errno(ret);
 545                 goto out_commit;
 546         }
 547
 548         if (input->chain == le16_to_cpu(cl->cl_next_free_rec)) {
 549                 le16_add_cpu(&cl->cl_next_free_rec, 1);
 550                 memset(cr, 0, sizeof(struct ocfs2_chain_rec));
 551         }
 552
 553         cr->c_blkno = cpu_to_le64(input->group);
 554         le32_add_cpu(&cr->c_total, input->clusters * cl_bpc);
 555         le32_add_cpu(&cr->c_free, input->frees * cl_bpc);
 556
 557         le32_add_cpu(&fe->id1.bitmap1.i_total, input->clusters *cl_bpc);
 558         le32_add_cpu(&fe->id1.bitmap1.i_used,
 559                      (input->clusters - input->frees) * cl_bpc);
 560         le32_add_cpu(&fe->i_clusters, input->clusters);
 561
 562         ocfs2_journal_dirty(handle, main_bm_bh);
 563
 564         spin_lock(&OCFS2_I(main_bm_inode)->ip_lock);
 565         OCFS2_I(main_bm_inode)->ip_clusters = le32_to_cpu(fe->i_clusters);
 566         le64_add_cpu(&fe->i_size, (u64)input->clusters << osb->s_clustersize_bits);
 567         spin_unlock(&OCFS2_I(main_bm_inode)->ip_lock);
 568         i_size_write(main_bm_inode, le64_to_cpu(fe->i_size));
 569
 570         ocfs2_update_super_and_backups(main_bm_inode, input->clusters);
 571
 572 out_commit:
 573         ocfs2_commit_trans(osb, handle);
 574
 575 out_free_group_bh:
 576         brelse(group_bh);
 577
 578 out_unlock:
 579         brelse(main_bm_bh);
 580
 581         ocfs2_inode_unlock(main_bm_inode, 1);
 582
 583 out_mutex:
 584         mutex_unlock(&main_bm_inode->i_mutex);
 585         iput(main_bm_inode);
 586
 587 out:
 588         return ret;
 589 }