fs/ocfs2/suballoc.c

   1 /* -*- mode: c; c-basic-offset: 8; -*-
   2  * vim: noexpandtab sw=8 ts=8 sts=0:
   3  *
   4  * suballoc.c
   5  *
   6  * metadata alloc and free
   7  * Inspired by ext3 block groups.
   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
  32 #define MLOG_MASK_PREFIX ML_DISK_ALLOC
  33 #include <cluster/masklog.h>
  34
  35 #include "ocfs2.h"
  36
  37 #include "alloc.h"
  38 #include "blockcheck.h"
  39 #include "dlmglue.h"
  40 #include "inode.h"
  41 #include "journal.h"
  42 #include "localalloc.h"
  43 #include "suballoc.h"
  44 #include "super.h"
  45 #include "sysfile.h"
  46 #include "uptodate.h"
  47
  48 #include "buffer_head_io.h"
  49
  50 #define NOT_ALLOC_NEW_GROUP             0
  51 #define ALLOC_NEW_GROUP                 0x1
  52 #define ALLOC_GROUPS_FROM_GLOBAL        0x2
  53
  54 #define OCFS2_MAX_TO_STEAL              1024
  55
  56 static inline void ocfs2_debug_bg(struct ocfs2_group_desc *bg);
  57 static inline void ocfs2_debug_suballoc_inode(struct ocfs2_dinode *fe);
  58 static inline u16 ocfs2_find_victim_chain(struct ocfs2_chain_list *cl);
  59 static int ocfs2_block_group_fill(handle_t *handle,
  60                                   struct inode *alloc_inode,
  61                                   struct buffer_head *bg_bh,
  62                                   u64 group_blkno,
  63                                   u16 my_chain,
  64                                   struct ocfs2_chain_list *cl);
  65 static int ocfs2_block_group_alloc(struct ocfs2_super *osb,
  66                                    struct inode *alloc_inode,
  67                                    struct buffer_head *bh,
  68                                    u64 max_block,
  69                                    u64 *last_alloc_group,
  70                                    int flags);
  71
  72 static int ocfs2_cluster_group_search(struct inode *inode,
  73                                       struct buffer_head *group_bh,
  74                                       u32 bits_wanted, u32 min_bits,
  75                                       u64 max_block,
  76                                       u16 *bit_off, u16 *bits_found);
  77 static int ocfs2_block_group_search(struct inode *inode,
  78                                     struct buffer_head *group_bh,
  79                                     u32 bits_wanted, u32 min_bits,
  80                                     u64 max_block,
  81                                     u16 *bit_off, u16 *bits_found);
  82 static int ocfs2_claim_suballoc_bits(struct ocfs2_super *osb,
  83                                      struct ocfs2_alloc_context *ac,
  84                                      handle_t *handle,
  85                                      u32 bits_wanted,
  86                                      u32 min_bits,
  87                                      u16 *bit_off,
  88                                      unsigned int *num_bits,
  89                                      u64 *bg_blkno);
  90 static int ocfs2_test_bg_bit_allocatable(struct buffer_head *bg_bh,
  91                                          int nr);
  92 static inline int ocfs2_block_group_set_bits(handle_t *handle,
  93                                              struct inode *alloc_inode,
  94                                              struct ocfs2_group_desc *bg,
  95                                              struct buffer_head *group_bh,
  96                                              unsigned int bit_off,
  97                                              unsigned int num_bits);
  98 static inline int ocfs2_block_group_clear_bits(handle_t *handle,
  99                                                struct inode *alloc_inode,
 100                                                struct ocfs2_group_desc *bg,
 101                                                struct buffer_head *group_bh,
 102                                                unsigned int bit_off,
 103                                                unsigned int num_bits);
 104
 105 static int ocfs2_relink_block_group(handle_t *handle,
 106                                     struct inode *alloc_inode,
 107                                     struct buffer_head *fe_bh,
 108                                     struct buffer_head *bg_bh,
 109                                     struct buffer_head *prev_bg_bh,
 110                                     u16 chain);
 111 static inline int ocfs2_block_group_reasonably_empty(struct ocfs2_group_desc *bg,
 112                                                      u32 wanted);
 113 static inline u32 ocfs2_desc_bitmap_to_cluster_off(struct inode *inode,
 114                                                    u64 bg_blkno,
 115                                                    u16 bg_bit_off);
 116 static inline void ocfs2_block_to_cluster_group(struct inode *inode,
 117                                                 u64 data_blkno,
 118                                                 u64 *bg_blkno,
 119                                                 u16 *bg_bit_off);
 120 static int ocfs2_reserve_clusters_with_limit(struct ocfs2_super *osb,
 121                                              u32 bits_wanted, u64 max_block,
 122                                              int flags,
 123                                              struct ocfs2_alloc_context **ac);
 124
 125 void ocfs2_free_ac_resource(struct ocfs2_alloc_context *ac)
 126 {
 127         struct inode *inode = ac->ac_inode;
 128
 129         if (inode) {
 130                 if (ac->ac_which != OCFS2_AC_USE_LOCAL)
 131                         ocfs2_inode_unlock(inode, 1);
 132
 133                 mutex_unlock(&inode->i_mutex);
 134
 135                 iput(inode);
 136                 ac->ac_inode = NULL;
 137         }
 138         brelse(ac->ac_bh);
 139         ac->ac_bh = NULL;
 140 }
 141
 142 void ocfs2_free_alloc_context(struct ocfs2_alloc_context *ac)
 143 {
 144         ocfs2_free_ac_resource(ac);
 145         kfree(ac);
 146 }
 147
 148 static u32 ocfs2_bits_per_group(struct ocfs2_chain_list *cl)
 149 {
 150         return (u32)le16_to_cpu(cl->cl_cpg) * (u32)le16_to_cpu(cl->cl_bpc);
 151 }
 152
 153 #define do_error(fmt, ...)                                              \
 154         do{                                                             \
 155                 if (clean_error)                                        \
 156                         mlog(ML_ERROR, fmt "\n", ##__VA_ARGS__);        \
 157                 else                                                    \
 158                         ocfs2_error(sb, fmt, ##__VA_ARGS__);            \
 159         } while (0)
 160
 161 static int ocfs2_validate_gd_self(struct super_block *sb,
 162                                   struct buffer_head *bh,
 163                                   int clean_error)
 164 {
 165         struct ocfs2_group_desc *gd = (struct ocfs2_group_desc *)bh->b_data;
 166
 167         if (!OCFS2_IS_VALID_GROUP_DESC(gd)) {
 168                 do_error("Group descriptor #%llu has bad signature %.*s",
 169                          (unsigned long long)bh->b_blocknr, 7,
 170                          gd->bg_signature);
 171                 return -EINVAL;
 172         }
 173
 174         if (le64_to_cpu(gd->bg_blkno) != bh->b_blocknr) {
 175                 do_error("Group descriptor #%llu has an invalid bg_blkno "
 176                          "of %llu",
 177                          (unsigned long long)bh->b_blocknr,
 178                          (unsigned long long)le64_to_cpu(gd->bg_blkno));
 179                 return -EINVAL;
 180         }
 181
 182         if (le32_to_cpu(gd->bg_generation) != OCFS2_SB(sb)->fs_generation) {
 183                 do_error("Group descriptor #%llu has an invalid "
 184                          "fs_generation of #%u",
 185                          (unsigned long long)bh->b_blocknr,
 186                          le32_to_cpu(gd->bg_generation));
 187                 return -EINVAL;
 188         }
 189
 190         if (le16_to_cpu(gd->bg_free_bits_count) > le16_to_cpu(gd->bg_bits)) {
 191                 do_error("Group descriptor #%llu has bit count %u but "
 192                          "claims that %u are free",
 193                          (unsigned long long)bh->b_blocknr,
 194                          le16_to_cpu(gd->bg_bits),
 195                          le16_to_cpu(gd->bg_free_bits_count));
 196                 return -EINVAL;
 197         }
 198
 199         if (le16_to_cpu(gd->bg_bits) > (8 * le16_to_cpu(gd->bg_size))) {
 200                 do_error("Group descriptor #%llu has bit count %u but "
 201                          "max bitmap bits of %u",
 202                          (unsigned long long)bh->b_blocknr,
 203                          le16_to_cpu(gd->bg_bits),
 204                          8 * le16_to_cpu(gd->bg_size));
 205                 return -EINVAL;
 206         }
 207
 208         return 0;
 209 }
 210
 211 static int ocfs2_validate_gd_parent(struct super_block *sb,
 212                                     struct ocfs2_dinode *di,
 213                                     struct buffer_head *bh,
 214                                     int clean_error)
 215 {
 216         unsigned int max_bits;
 217         struct ocfs2_group_desc *gd = (struct ocfs2_group_desc *)bh->b_data;
 218
 219         if (di->i_blkno != gd->bg_parent_dinode) {
 220                 do_error("Group descriptor #%llu has bad parent "
 221                          "pointer (%llu, expected %llu)",
 222                          (unsigned long long)bh->b_blocknr,
 223                          (unsigned long long)le64_to_cpu(gd->bg_parent_dinode),
 224                          (unsigned long long)le64_to_cpu(di->i_blkno));
 225                 return -EINVAL;
 226         }
 227
 228         max_bits = le16_to_cpu(di->id2.i_chain.cl_cpg) * le16_to_cpu(di->id2.i_chain.cl_bpc);
 229         if (le16_to_cpu(gd->bg_bits) > max_bits) {
 230                 do_error("Group descriptor #%llu has bit count of %u",
 231                          (unsigned long long)bh->b_blocknr,
 232                          le16_to_cpu(gd->bg_bits));
 233                 return -EINVAL;
 234         }
 235
 236         if (le16_to_cpu(gd->bg_chain) >=
 237             le16_to_cpu(di->id2.i_chain.cl_next_free_rec)) {
 238                 do_error("Group descriptor #%llu has bad chain %u",
 239                          (unsigned long long)bh->b_blocknr,
 240                          le16_to_cpu(gd->bg_chain));
 241                 return -EINVAL;
 242         }
 243
 244         return 0;
 245 }
 246
 247 #undef do_error
 248
 249 /*
 250  * This version only prints errors.  It does not fail the filesystem, and
 251  * exists only for resize.
 252  */
 253 int ocfs2_check_group_descriptor(struct super_block *sb,
 254                                  struct ocfs2_dinode *di,
 255                                  struct buffer_head *bh)
 256 {
 257         int rc;
 258         struct ocfs2_group_desc *gd = (struct ocfs2_group_desc *)bh->b_data;
 259
 260         BUG_ON(!buffer_uptodate(bh));
 261
 262         /*
 263          * If the ecc fails, we return the error but otherwise
 264          * leave the filesystem running.  We know any error is
 265          * local to this block.
 266          */
 267         rc = ocfs2_validate_meta_ecc(sb, bh->b_data, &gd->bg_check);
 268         if (rc) {
 269                 mlog(ML_ERROR,
 270                      "Checksum failed for group descriptor %llu\n",
 271                      (unsigned long long)bh->b_blocknr);
 272         } else
 273                 rc = ocfs2_validate_gd_self(sb, bh, 1);
 274         if (!rc)
 275                 rc = ocfs2_validate_gd_parent(sb, di, bh, 1);
 276
 277         return rc;
 278 }
 279
 280 static int ocfs2_validate_group_descriptor(struct super_block *sb,
 281                                            struct buffer_head *bh)
 282 {
 283         int rc;
 284         struct ocfs2_group_desc *gd = (struct ocfs2_group_desc *)bh->b_data;
 285
 286         mlog(0, "Validating group descriptor %llu\n",
 287              (unsigned long long)bh->b_blocknr);
 288
 289         BUG_ON(!buffer_uptodate(bh));
 290
 291         /*
 292          * If the ecc fails, we return the error but otherwise
 293          * leave the filesystem running.  We know any error is
 294          * local to this block.
 295          */
 296         rc = ocfs2_validate_meta_ecc(sb, bh->b_data, &gd->bg_check);
 297         if (rc)
 298                 return rc;
 299
 300         /*
 301          * Errors after here are fatal.
 302          */
 303
 304         return ocfs2_validate_gd_self(sb, bh, 0);
 305 }
 306
 307 int ocfs2_read_group_descriptor(struct inode *inode, struct ocfs2_dinode *di,
 308                                 u64 gd_blkno, struct buffer_head **bh)
 309 {
 310         int rc;
 311         struct buffer_head *tmp = *bh;
 312
 313         rc = ocfs2_read_block(INODE_CACHE(inode), gd_blkno, &tmp,
 314                               ocfs2_validate_group_descriptor);
 315         if (rc)
 316                 goto out;
 317
 318         rc = ocfs2_validate_gd_parent(inode->i_sb, di, tmp, 0);
 319         if (rc) {
 320                 brelse(tmp);
 321                 goto out;
 322         }
 323
 324         /* If ocfs2_read_block() got us a new bh, pass it up. */
 325         if (!*bh)
 326                 *bh = tmp;
 327
 328 out:
 329         return rc;
 330 }
 331
 332 static int ocfs2_block_group_fill(handle_t *handle,
 333                                   struct inode *alloc_inode,
 334                                   struct buffer_head *bg_bh,
 335                                   u64 group_blkno,
 336                                   u16 my_chain,
 337                                   struct ocfs2_chain_list *cl)
 338 {
 339         int status = 0;
 340         struct ocfs2_group_desc *bg = (struct ocfs2_group_desc *) bg_bh->b_data;
 341         struct super_block * sb = alloc_inode->i_sb;
 342
 343         mlog_entry_void();
 344
 345         if (((unsigned long long) bg_bh->b_blocknr) != group_blkno) {
 346                 ocfs2_error(alloc_inode->i_sb, "group block (%llu) != "
 347                             "b_blocknr (%llu)",
 348                             (unsigned long long)group_blkno,
 349                             (unsigned long long) bg_bh->b_blocknr);
 350                 status = -EIO;
 351                 goto bail;
 352         }
 353
 354         status = ocfs2_journal_access_gd(handle,
 355                                          INODE_CACHE(alloc_inode),
 356                                          bg_bh,
 357                                          OCFS2_JOURNAL_ACCESS_CREATE);
 358         if (status < 0) {
 359                 mlog_errno(status);
 360                 goto bail;
 361         }
 362
 363         memset(bg, 0, sb->s_blocksize);
 364         strcpy(bg->bg_signature, OCFS2_GROUP_DESC_SIGNATURE);
 365         bg->bg_generation = cpu_to_le32(OCFS2_SB(sb)->fs_generation);
 366         bg->bg_size = cpu_to_le16(ocfs2_group_bitmap_size(sb));
 367         bg->bg_bits = cpu_to_le16(ocfs2_bits_per_group(cl));
 368         bg->bg_chain = cpu_to_le16(my_chain);
 369         bg->bg_next_group = cl->cl_recs[my_chain].c_blkno;
 370         bg->bg_parent_dinode = cpu_to_le64(OCFS2_I(alloc_inode)->ip_blkno);
 371         bg->bg_blkno = cpu_to_le64(group_blkno);
 372         /* set the 1st bit in the bitmap to account for the descriptor block */
 373         ocfs2_set_bit(0, (unsigned long *)bg->bg_bitmap);
 374         bg->bg_free_bits_count = cpu_to_le16(le16_to_cpu(bg->bg_bits) - 1);
 375
 376         status = ocfs2_journal_dirty(handle, bg_bh);
 377         if (status < 0)
 378                 mlog_errno(status);
 379
 380         /* There is no need to zero out or otherwise initialize the
 381          * other blocks in a group - All valid FS metadata in a block
 382          * group stores the superblock fs_generation value at
 383          * allocation time. */
 384
 385 bail:
 386         mlog_exit(status);
 387         return status;
 388 }
 389
 390 static inline u16 ocfs2_find_smallest_chain(struct ocfs2_chain_list *cl)
 391 {
 392         u16 curr, best;
 393
 394         best = curr = 0;
 395         while (curr < le16_to_cpu(cl->cl_count)) {
 396                 if (le32_to_cpu(cl->cl_recs[best].c_total) >
 397                     le32_to_cpu(cl->cl_recs[curr].c_total))
 398                         best = curr;
 399                 curr++;
 400         }
 401         return best;
 402 }
 403
 404 /*
 405  * We expect the block group allocator to already be locked.
 406  */
 407 static int ocfs2_block_group_alloc(struct ocfs2_super *osb,
 408                                    struct inode *alloc_inode,
 409                                    struct buffer_head *bh,
 410                                    u64 max_block,
 411                                    u64 *last_alloc_group,
 412                                    int flags)
 413 {
 414         int status, credits;
 415         struct ocfs2_dinode *fe = (struct ocfs2_dinode *) bh->b_data;
 416         struct ocfs2_chain_list *cl;
 417         struct ocfs2_alloc_context *ac = NULL;
 418         handle_t *handle = NULL;
 419         u32 bit_off, num_bits;
 420         u16 alloc_rec;
 421         u64 bg_blkno;
 422         struct buffer_head *bg_bh = NULL;
 423         struct ocfs2_group_desc *bg;
 424
 425         BUG_ON(ocfs2_is_cluster_bitmap(alloc_inode));
 426
 427         mlog_entry_void();
 428
 429         cl = &fe->id2.i_chain;
 430         status = ocfs2_reserve_clusters_with_limit(osb,
 431                                                    le16_to_cpu(cl->cl_cpg),
 432                                                    max_block, flags, &ac);
 433         if (status < 0) {
 434                 if (status != -ENOSPC)
 435                         mlog_errno(status);
 436                 goto bail;
 437         }
 438
 439         credits = ocfs2_calc_group_alloc_credits(osb->sb,
 440                                                  le16_to_cpu(cl->cl_cpg));
 441         handle = ocfs2_start_trans(osb, credits);
 442         if (IS_ERR(handle)) {
 443                 status = PTR_ERR(handle);
 444                 handle = NULL;
 445                 mlog_errno(status);
 446                 goto bail;
 447         }
 448
 449         if (last_alloc_group && *last_alloc_group != 0) {
 450                 mlog(0, "use old allocation group %llu for block group alloc\n",
 451                      (unsigned long long)*last_alloc_group);
 452                 ac->ac_last_group = *last_alloc_group;
 453         }
 454         status = ocfs2_claim_clusters(osb,
 455                                       handle,
 456                                       ac,
 457                                       le16_to_cpu(cl->cl_cpg),
 458                                       &bit_off,
 459                                       &num_bits);
 460         if (status < 0) {
 461                 if (status != -ENOSPC)
 462                         mlog_errno(status);
 463                 goto bail;
 464         }
 465
 466         alloc_rec = ocfs2_find_smallest_chain(cl);
 467
 468         /* setup the group */
 469         bg_blkno = ocfs2_clusters_to_blocks(osb->sb, bit_off);
 470         mlog(0, "new descriptor, record %u, at block %llu\n",
 471              alloc_rec, (unsigned long long)bg_blkno);
 472
 473         bg_bh = sb_getblk(osb->sb, bg_blkno);
 474         if (!bg_bh) {
 475                 status = -EIO;
 476                 mlog_errno(status);
 477                 goto bail;
 478         }
 479         ocfs2_set_new_buffer_uptodate(INODE_CACHE(alloc_inode), bg_bh);
 480
 481         status = ocfs2_block_group_fill(handle,
 482                                         alloc_inode,
 483                                         bg_bh,
 484                                         bg_blkno,
 485                                         alloc_rec,
 486                                         cl);
 487         if (status < 0) {
 488                 mlog_errno(status);
 489                 goto bail;
 490         }
 491
 492         bg = (struct ocfs2_group_desc *) bg_bh->b_data;
 493
 494         status = ocfs2_journal_access_di(handle, INODE_CACHE(alloc_inode),
 495                                          bh, OCFS2_JOURNAL_ACCESS_WRITE);
 496         if (status < 0) {
 497                 mlog_errno(status);
 498                 goto bail;
 499         }
 500
 501         le32_add_cpu(&cl->cl_recs[alloc_rec].c_free,
 502                      le16_to_cpu(bg->bg_free_bits_count));
 503         le32_add_cpu(&cl->cl_recs[alloc_rec].c_total, le16_to_cpu(bg->bg_bits));
 504         cl->cl_recs[alloc_rec].c_blkno  = cpu_to_le64(bg_blkno);
 505         if (le16_to_cpu(cl->cl_next_free_rec) < le16_to_cpu(cl->cl_count))
 506                 le16_add_cpu(&cl->cl_next_free_rec, 1);
 507
 508         le32_add_cpu(&fe->id1.bitmap1.i_used, le16_to_cpu(bg->bg_bits) -
 509                                         le16_to_cpu(bg->bg_free_bits_count));
 510         le32_add_cpu(&fe->id1.bitmap1.i_total, le16_to_cpu(bg->bg_bits));
 511         le32_add_cpu(&fe->i_clusters, le16_to_cpu(cl->cl_cpg));
 512
 513         status = ocfs2_journal_dirty(handle, bh);
 514         if (status < 0) {
 515                 mlog_errno(status);
 516                 goto bail;
 517         }
 518
 519         spin_lock(&OCFS2_I(alloc_inode)->ip_lock);
 520         OCFS2_I(alloc_inode)->ip_clusters = le32_to_cpu(fe->i_clusters);
 521         fe->i_size = cpu_to_le64(ocfs2_clusters_to_bytes(alloc_inode->i_sb,
 522                                              le32_to_cpu(fe->i_clusters)));
 523         spin_unlock(&OCFS2_I(alloc_inode)->ip_lock);
 524         i_size_write(alloc_inode, le64_to_cpu(fe->i_size));
 525         alloc_inode->i_blocks = ocfs2_inode_sector_count(alloc_inode);
 526
 527         status = 0;
 528
 529         /* save the new last alloc group so that the caller can cache it. */
 530         if (last_alloc_group)
 531                 *last_alloc_group = ac->ac_last_group;
 532
 533 bail:
 534         if (handle)
 535                 ocfs2_commit_trans(osb, handle);
 536
 537         if (ac)
 538                 ocfs2_free_alloc_context(ac);
 539
 540         brelse(bg_bh);
 541
 542         mlog_exit(status);
 543         return status;
 544 }
 545
 546 static int ocfs2_reserve_suballoc_bits(struct ocfs2_super *osb,
 547                                        struct ocfs2_alloc_context *ac,
 548                                        int type,
 549                                        u32 slot,
 550                                        u64 *last_alloc_group,
 551                                        int flags)
 552 {
 553         int status;
 554         u32 bits_wanted = ac->ac_bits_wanted;
 555         struct inode *alloc_inode;
 556         struct buffer_head *bh = NULL;
 557         struct ocfs2_dinode *fe;
 558         u32 free_bits;
 559
 560         mlog_entry_void();
 561
 562         alloc_inode = ocfs2_get_system_file_inode(osb, type, slot);
 563         if (!alloc_inode) {
 564                 mlog_errno(-EINVAL);
 565                 return -EINVAL;
 566         }
 567
 568         mutex_lock(&alloc_inode->i_mutex);
 569
 570         status = ocfs2_inode_lock(alloc_inode, &bh, 1);
 571         if (status < 0) {
 572                 mutex_unlock(&alloc_inode->i_mutex);
 573                 iput(alloc_inode);
 574
 575                 mlog_errno(status);
 576                 return status;
 577         }
 578
 579         ac->ac_inode = alloc_inode;
 580         ac->ac_alloc_slot = slot;
 581
 582         fe = (struct ocfs2_dinode *) bh->b_data;
 583
 584         /* The bh was validated by the inode read inside
 585          * ocfs2_inode_lock().  Any corruption is a code bug. */
 586         BUG_ON(!OCFS2_IS_VALID_DINODE(fe));
 587
 588         if (!(fe->i_flags & cpu_to_le32(OCFS2_CHAIN_FL))) {
 589                 ocfs2_error(alloc_inode->i_sb, "Invalid chain allocator %llu",
 590                             (unsigned long long)le64_to_cpu(fe->i_blkno));
 591                 status = -EIO;
 592                 goto bail;
 593         }
 594
 595         free_bits = le32_to_cpu(fe->id1.bitmap1.i_total) -
 596                 le32_to_cpu(fe->id1.bitmap1.i_used);
 597
 598         if (bits_wanted > free_bits) {
 599                 /* cluster bitmap never grows */
 600                 if (ocfs2_is_cluster_bitmap(alloc_inode)) {
 601                         mlog(0, "Disk Full: wanted=%u, free_bits=%u\n",
 602                              bits_wanted, free_bits);
 603                         status = -ENOSPC;
 604                         goto bail;
 605                 }
 606
 607                 if (!(flags & ALLOC_NEW_GROUP)) {
 608                         mlog(0, "Alloc File %u Full: wanted=%u, free_bits=%u, "
 609                              "and we don't alloc a new group for it.\n",
 610                              slot, bits_wanted, free_bits);
 611                         status = -ENOSPC;
 612                         goto bail;
 613                 }
 614
 615                 status = ocfs2_block_group_alloc(osb, alloc_inode, bh,
 616                                                  ac->ac_max_block,
 617                                                  last_alloc_group, flags);
 618                 if (status < 0) {
 619                         if (status != -ENOSPC)
 620                                 mlog_errno(status);
 621                         goto bail;
 622                 }
 623                 atomic_inc(&osb->alloc_stats.bg_extends);
 624
 625                 /* You should never ask for this much metadata */
 626                 BUG_ON(bits_wanted >
 627                        (le32_to_cpu(fe->id1.bitmap1.i_total)
 628                         - le32_to_cpu(fe->id1.bitmap1.i_used)));
 629         }
 630
 631         get_bh(bh);
 632         ac->ac_bh = bh;
 633 bail:
 634         brelse(bh);
 635
 636         mlog_exit(status);
 637         return status;
 638 }
 639
 640 static void ocfs2_init_inode_steal_slot(struct ocfs2_super *osb)
 641 {
 642         spin_lock(&osb->osb_lock);
 643         osb->s_inode_steal_slot = OCFS2_INVALID_SLOT;
 644         spin_unlock(&osb->osb_lock);
 645         atomic_set(&osb->s_num_inodes_stolen, 0);
 646 }
 647
 648 static void ocfs2_init_meta_steal_slot(struct ocfs2_super *osb)
 649 {
 650         spin_lock(&osb->osb_lock);
 651         osb->s_meta_steal_slot = OCFS2_INVALID_SLOT;
 652         spin_unlock(&osb->osb_lock);
 653         atomic_set(&osb->s_num_meta_stolen, 0);
 654 }
 655
 656 void ocfs2_init_steal_slots(struct ocfs2_super *osb)
 657 {
 658         ocfs2_init_inode_steal_slot(osb);
 659         ocfs2_init_meta_steal_slot(osb);
 660 }
 661
 662 static void __ocfs2_set_steal_slot(struct ocfs2_super *osb, int slot, int type)
 663 {
 664         spin_lock(&osb->osb_lock);
 665         if (type == INODE_ALLOC_SYSTEM_INODE)
 666                 osb->s_inode_steal_slot = slot;
 667         else if (type == EXTENT_ALLOC_SYSTEM_INODE)
 668                 osb->s_meta_steal_slot = slot;
 669         spin_unlock(&osb->osb_lock);
 670 }
 671
 672 static int __ocfs2_get_steal_slot(struct ocfs2_super *osb, int type)
 673 {
 674         int slot = OCFS2_INVALID_SLOT;
 675
 676         spin_lock(&osb->osb_lock);
 677         if (type == INODE_ALLOC_SYSTEM_INODE)
 678                 slot = osb->s_inode_steal_slot;
 679         else if (type == EXTENT_ALLOC_SYSTEM_INODE)
 680                 slot = osb->s_meta_steal_slot;
 681         spin_unlock(&osb->osb_lock);
 682
 683         return slot;
 684 }
 685
 686 static int ocfs2_get_inode_steal_slot(struct ocfs2_super *osb)
 687 {
 688         return __ocfs2_get_steal_slot(osb, INODE_ALLOC_SYSTEM_INODE);
 689 }
 690
 691 static int ocfs2_get_meta_steal_slot(struct ocfs2_super *osb)
 692 {
 693         return __ocfs2_get_steal_slot(osb, EXTENT_ALLOC_SYSTEM_INODE);
 694 }
 695
 696 static int ocfs2_steal_resource(struct ocfs2_super *osb,
 697                                 struct ocfs2_alloc_context *ac,
 698                                 int type)
 699 {
 700         int i, status = -ENOSPC;
 701         int slot = __ocfs2_get_steal_slot(osb, type);
 702
 703         /* Start to steal resource from the first slot after ours. */
 704         if (slot == OCFS2_INVALID_SLOT)
 705                 slot = osb->slot_num + 1;
 706
 707         for (i = 0; i < osb->max_slots; i++, slot++) {
 708                 if (slot == osb->max_slots)
 709                         slot = 0;
 710
 711                 if (slot == osb->slot_num)
 712                         continue;
 713
 714                 status = ocfs2_reserve_suballoc_bits(osb, ac,
 715                                                      type,
 716                                                      (u32)slot, NULL,
 717                                                      NOT_ALLOC_NEW_GROUP);
 718                 if (status >= 0) {
 719                         __ocfs2_set_steal_slot(osb, slot, type);
 720                         break;
 721                 }
 722
 723                 ocfs2_free_ac_resource(ac);
 724         }
 725
 726         return status;
 727 }
 728
 729 static int ocfs2_steal_inode(struct ocfs2_super *osb,
 730                              struct ocfs2_alloc_context *ac)
 731 {
 732         return ocfs2_steal_resource(osb, ac, INODE_ALLOC_SYSTEM_INODE);
 733 }
 734
 735 static int ocfs2_steal_meta(struct ocfs2_super *osb,
 736                             struct ocfs2_alloc_context *ac)
 737 {
 738         return ocfs2_steal_resource(osb, ac, EXTENT_ALLOC_SYSTEM_INODE);
 739 }
 740
 741 int ocfs2_reserve_new_metadata_blocks(struct ocfs2_super *osb,
 742                                       int blocks,
 743                                       struct ocfs2_alloc_context **ac)
 744 {
 745         int status;
 746         int slot = ocfs2_get_meta_steal_slot(osb);
 747
 748         *ac = kzalloc(sizeof(struct ocfs2_alloc_context), GFP_KERNEL);
 749         if (!(*ac)) {
 750                 status = -ENOMEM;
 751                 mlog_errno(status);
 752                 goto bail;
 753         }
 754
 755         (*ac)->ac_bits_wanted = blocks;
 756         (*ac)->ac_which = OCFS2_AC_USE_META;
 757         (*ac)->ac_group_search = ocfs2_block_group_search;
 758
 759         if (slot != OCFS2_INVALID_SLOT &&
 760                 atomic_read(&osb->s_num_meta_stolen) < OCFS2_MAX_TO_STEAL)
 761                 goto extent_steal;
 762
 763         atomic_set(&osb->s_num_meta_stolen, 0);
 764         status = ocfs2_reserve_suballoc_bits(osb, (*ac),
 765                                              EXTENT_ALLOC_SYSTEM_INODE,
 766                                              (u32)osb->slot_num, NULL,
 767                                              ALLOC_NEW_GROUP);
 768
 769
 770         if (status >= 0) {
 771                 status = 0;
 772                 if (slot != OCFS2_INVALID_SLOT)
 773                         ocfs2_init_meta_steal_slot(osb);
 774                 goto bail;
 775         } else if (status < 0 && status != -ENOSPC) {
 776                 mlog_errno(status);
 777                 goto bail;
 778         }
 779
 780         ocfs2_free_ac_resource(*ac);
 781
 782 extent_steal:
 783         status = ocfs2_steal_meta(osb, *ac);
 784         atomic_inc(&osb->s_num_meta_stolen);
 785         if (status < 0) {
 786                 if (status != -ENOSPC)
 787                         mlog_errno(status);
 788                 goto bail;
 789         }
 790
 791         status = 0;
 792 bail:
 793         if ((status < 0) && *ac) {
 794                 ocfs2_free_alloc_context(*ac);
 795                 *ac = NULL;
 796         }
 797
 798         mlog_exit(status);
 799         return status;
 800 }
 801
 802 int ocfs2_reserve_new_metadata(struct ocfs2_super *osb,
 803                                struct ocfs2_extent_list *root_el,
 804                                struct ocfs2_alloc_context **ac)
 805 {
 806         return ocfs2_reserve_new_metadata_blocks(osb,
 807                                         ocfs2_extend_meta_needed(root_el),
 808                                         ac);
 809 }
 810
 811 int ocfs2_reserve_new_inode(struct ocfs2_super *osb,
 812                             struct ocfs2_alloc_context **ac)
 813 {
 814         int status;
 815         int slot = ocfs2_get_inode_steal_slot(osb);
 816         u64 alloc_group;
 817
 818         *ac = kzalloc(sizeof(struct ocfs2_alloc_context), GFP_KERNEL);
 819         if (!(*ac)) {
 820                 status = -ENOMEM;
 821                 mlog_errno(status);
 822                 goto bail;
 823         }
 824
 825         (*ac)->ac_bits_wanted = 1;
 826         (*ac)->ac_which = OCFS2_AC_USE_INODE;
 827
 828         (*ac)->ac_group_search = ocfs2_block_group_search;
 829
 830         /*
 831          * stat(2) can't handle i_ino > 32bits, so we tell the
 832          * lower levels not to allocate us a block group past that
 833          * limit.  The 'inode64' mount option avoids this behavior.
 834          */
 835         if (!(osb->s_mount_opt & OCFS2_MOUNT_INODE64))
 836                 (*ac)->ac_max_block = (u32)~0U;
 837
 838         /*
 839          * slot is set when we successfully steal inode from other nodes.
 840          * It is reset in 3 places:
 841          * 1. when we flush the truncate log
 842          * 2. when we complete local alloc recovery.
 843          * 3. when we successfully allocate from our own slot.
 844          * After it is set, we will go on stealing inodes until we find the
 845          * need to check our slots to see whether there is some space for us.
 846          */
 847         if (slot != OCFS2_INVALID_SLOT &&
 848             atomic_read(&osb->s_num_inodes_stolen) < OCFS2_MAX_TO_STEAL)
 849                 goto inode_steal;
 850
 851         atomic_set(&osb->s_num_inodes_stolen, 0);
 852         alloc_group = osb->osb_inode_alloc_group;
 853         status = ocfs2_reserve_suballoc_bits(osb, *ac,
 854                                              INODE_ALLOC_SYSTEM_INODE,
 855                                              (u32)osb->slot_num,
 856                                              &alloc_group,
 857                                              ALLOC_NEW_GROUP |
 858                                              ALLOC_GROUPS_FROM_GLOBAL);
 859         if (status >= 0) {
 860                 status = 0;
 861
 862                 spin_lock(&osb->osb_lock);
 863                 osb->osb_inode_alloc_group = alloc_group;
 864                 spin_unlock(&osb->osb_lock);
 865                 mlog(0, "after reservation, new allocation group is "
 866                      "%llu\n", (unsigned long long)alloc_group);
 867
 868                 /*
 869                  * Some inodes must be freed by us, so try to allocate
 870                  * from our own next time.
 871                  */
 872                 if (slot != OCFS2_INVALID_SLOT)
 873                         ocfs2_init_inode_steal_slot(osb);
 874                 goto bail;
 875         } else if (status < 0 && status != -ENOSPC) {
 876                 mlog_errno(status);
 877                 goto bail;
 878         }
 879
 880         ocfs2_free_ac_resource(*ac);
 881
 882 inode_steal:
 883         status = ocfs2_steal_inode(osb, *ac);
 884         atomic_inc(&osb->s_num_inodes_stolen);
 885         if (status < 0) {
 886                 if (status != -ENOSPC)
 887                         mlog_errno(status);
 888                 goto bail;
 889         }
 890
 891         status = 0;
 892 bail:
 893         if ((status < 0) && *ac) {
 894                 ocfs2_free_alloc_context(*ac);
 895                 *ac = NULL;
 896         }
 897
 898         mlog_exit(status);
 899         return status;
 900 }
 901
 902 /* local alloc code has to do the same thing, so rather than do this
 903  * twice.. */
 904 int ocfs2_reserve_cluster_bitmap_bits(struct ocfs2_super *osb,
 905                                       struct ocfs2_alloc_context *ac)
 906 {
 907         int status;
 908
 909         ac->ac_which = OCFS2_AC_USE_MAIN;
 910         ac->ac_group_search = ocfs2_cluster_group_search;
 911
 912         status = ocfs2_reserve_suballoc_bits(osb, ac,
 913                                              GLOBAL_BITMAP_SYSTEM_INODE,
 914                                              OCFS2_INVALID_SLOT, NULL,
 915                                              ALLOC_NEW_GROUP);
 916         if (status < 0 && status != -ENOSPC) {
 917                 mlog_errno(status);
 918                 goto bail;
 919         }
 920
 921 bail:
 922         return status;
 923 }
 924
 925 /* Callers don't need to care which bitmap (local alloc or main) to
 926  * use so we figure it out for them, but unfortunately this clutters
 927  * things a bit. */
 928 static int ocfs2_reserve_clusters_with_limit(struct ocfs2_super *osb,
 929                                              u32 bits_wanted, u64 max_block,
 930                                              int flags,
 931                                              struct ocfs2_alloc_context **ac)
 932 {
 933         int status;
 934
 935         mlog_entry_void();
 936
 937         *ac = kzalloc(sizeof(struct ocfs2_alloc_context), GFP_KERNEL);
 938         if (!(*ac)) {
 939                 status = -ENOMEM;
 940                 mlog_errno(status);
 941                 goto bail;
 942         }
 943
 944         (*ac)->ac_bits_wanted = bits_wanted;
 945         (*ac)->ac_max_block = max_block;
 946
 947         status = -ENOSPC;
 948         if (!(flags & ALLOC_GROUPS_FROM_GLOBAL) &&
 949             ocfs2_alloc_should_use_local(osb, bits_wanted)) {
 950                 status = ocfs2_reserve_local_alloc_bits(osb,
 951                                                         bits_wanted,
 952                                                         *ac);
 953                 if (status == -EFBIG) {
 954                         /* The local alloc window is outside ac_max_block.
 955                          * use the main bitmap. */
 956                         status = -ENOSPC;
 957                 } else if ((status < 0) && (status != -ENOSPC)) {
 958                         mlog_errno(status);
 959                         goto bail;
 960                 }
 961         }
 962
 963         if (status == -ENOSPC) {
 964                 status = ocfs2_reserve_cluster_bitmap_bits(osb, *ac);
 965                 if (status < 0) {
 966                         if (status != -ENOSPC)
 967                                 mlog_errno(status);
 968                         goto bail;
 969                 }
 970         }
 971
 972         status = 0;
 973 bail:
 974         if ((status < 0) && *ac) {
 975                 ocfs2_free_alloc_context(*ac);
 976                 *ac = NULL;
 977         }
 978
 979         mlog_exit(status);
 980         return status;
 981 }
 982
 983 int ocfs2_reserve_clusters(struct ocfs2_super *osb,
 984                            u32 bits_wanted,
 985                            struct ocfs2_alloc_context **ac)
 986 {
 987         return ocfs2_reserve_clusters_with_limit(osb, bits_wanted, 0,
 988                                                  ALLOC_NEW_GROUP, ac);
 989 }
 990
 991 /*
 992  * More or less lifted from ext3. I'll leave their description below:
 993  *
 994  * "For ext3 allocations, we must not reuse any blocks which are
 995  * allocated in the bitmap buffer's "last committed data" copy.  This
 996  * prevents deletes from freeing up the page for reuse until we have
 997  * committed the delete transaction.
 998  *
 999  * If we didn't do this, then deleting something and reallocating it as
1000  * data would allow the old block to be overwritten before the
1001  * transaction committed (because we force data to disk before commit).
1002  * This would lead to corruption if we crashed between overwriting the
1003  * data and committing the delete.
1004  *
1005  * @@@ We may want to make this allocation behaviour conditional on
1006  * data-writes at some point, and disable it for metadata allocations or
1007  * sync-data inodes."
1008  *
1009  * Note: OCFS2 already does this differently for metadata vs data
1010  * allocations, as those bitmaps are separate and undo access is never
1011  * called on a metadata group descriptor.
1012  */
1013 static int ocfs2_test_bg_bit_allocatable(struct buffer_head *bg_bh,
1014                                          int nr)
1015 {
1016         struct ocfs2_group_desc *bg = (struct ocfs2_group_desc *) bg_bh->b_data;
1017         int ret;
1018
1019         if (ocfs2_test_bit(nr, (unsigned long *)bg->bg_bitmap))
1020                 return 0;
1021
1022         if (!buffer_jbd(bg_bh))
1023                 return 1;
1024
1025         jbd_lock_bh_state(bg_bh);
1026         bg = (struct ocfs2_group_desc *) bh2jh(bg_bh)->b_committed_data;
1027         if (bg)
1028                 ret = !ocfs2_test_bit(nr, (unsigned long *)bg->bg_bitmap);
1029         else
1030                 ret = 1;
1031         jbd_unlock_bh_state(bg_bh);
1032
1033         return ret;
1034 }
1035
1036 static int ocfs2_block_group_find_clear_bits(struct ocfs2_super *osb,
1037                                              struct buffer_head *bg_bh,
1038                                              unsigned int bits_wanted,
1039                                              unsigned int total_bits,
1040                                              u16 *bit_off,
1041                                              u16 *bits_found)
1042 {
1043         void *bitmap;
1044         u16 best_offset, best_size;
1045         int offset, start, found, status = 0;
1046         struct ocfs2_group_desc *bg = (struct ocfs2_group_desc *) bg_bh->b_data;
1047
1048         /* Callers got this descriptor from
1049          * ocfs2_read_group_descriptor().  Any corruption is a code bug. */
1050         BUG_ON(!OCFS2_IS_VALID_GROUP_DESC(bg));
1051
1052         found = start = best_offset = best_size = 0;
1053         bitmap = bg->bg_bitmap;
1054
1055         while((offset = ocfs2_find_next_zero_bit(bitmap, total_bits, start)) != -1) {
1056                 if (offset == total_bits)
1057                         break;
1058
1059                 if (!ocfs2_test_bg_bit_allocatable(bg_bh, offset)) {
1060                         /* We found a zero, but we can't use it as it
1061                          * hasn't been put to disk yet! */
1062                         found = 0;
1063                         start = offset + 1;
1064                 } else if (offset == start) {
1065                         /* we found a zero */
1066                         found++;
1067                         /* move start to the next bit to test */
1068                         start++;
1069                 } else {
1070                         /* got a zero after some ones */
1071                         found = 1;
1072                         start = offset + 1;
1073                 }
1074                 if (found > best_size) {
1075                         best_size = found;
1076                         best_offset = start - found;
1077                 }
1078                 /* we got everything we needed */
1079                 if (found == bits_wanted) {
1080                         /* mlog(0, "Found it all!\n"); */
1081                         break;
1082                 }
1083         }
1084
1085         /* XXX: I think the first clause is equivalent to the second
1086          *      - jlbec */
1087         if (found == bits_wanted) {
1088                 *bit_off = start - found;
1089                 *bits_found = found;
1090         } else if (best_size) {
1091                 *bit_off = best_offset;
1092                 *bits_found = best_size;
1093         } else {
1094                 status = -ENOSPC;
1095                 /* No error log here -- see the comment above
1096                  * ocfs2_test_bg_bit_allocatable */
1097         }
1098
1099         return status;
1100 }
1101
1102 static inline int ocfs2_block_group_set_bits(handle_t *handle,
1103                                              struct inode *alloc_inode,
1104                                              struct ocfs2_group_desc *bg,
1105                                              struct buffer_head *group_bh,
1106                                              unsigned int bit_off,
1107                                              unsigned int num_bits)
1108 {
1109         int status;
1110         void *bitmap = bg->bg_bitmap;
1111         int journal_type = OCFS2_JOURNAL_ACCESS_WRITE;
1112
1113         mlog_entry_void();
1114
1115         /* All callers get the descriptor via
1116          * ocfs2_read_group_descriptor().  Any corruption is a code bug. */
1117         BUG_ON(!OCFS2_IS_VALID_GROUP_DESC(bg));
1118         BUG_ON(le16_to_cpu(bg->bg_free_bits_count) < num_bits);
1119
1120         mlog(0, "block_group_set_bits: off = %u, num = %u\n", bit_off,
1121              num_bits);
1122
1123         if (ocfs2_is_cluster_bitmap(alloc_inode))
1124                 journal_type = OCFS2_JOURNAL_ACCESS_UNDO;
1125
1126         status = ocfs2_journal_access_gd(handle,
1127                                          INODE_CACHE(alloc_inode),
1128                                          group_bh,
1129                                          journal_type);
1130         if (status < 0) {
1131                 mlog_errno(status);
1132                 goto bail;
1133         }
1134
1135         le16_add_cpu(&bg->bg_free_bits_count, -num_bits);
1136
1137         while(num_bits--)
1138                 ocfs2_set_bit(bit_off++, bitmap);
1139
1140         status = ocfs2_journal_dirty(handle,
1141                                      group_bh);
1142         if (status < 0) {
1143                 mlog_errno(status);
1144                 goto bail;
1145         }
1146
1147 bail:
1148         mlog_exit(status);
1149         return status;
1150 }
1151
1152 /* find the one with the most empty bits */
1153 static inline u16 ocfs2_find_victim_chain(struct ocfs2_chain_list *cl)
1154 {
1155         u16 curr, best;
1156
1157         BUG_ON(!cl->cl_next_free_rec);
1158
1159         best = curr = 0;
1160         while (curr < le16_to_cpu(cl->cl_next_free_rec)) {
1161                 if (le32_to_cpu(cl->cl_recs[curr].c_free) >
1162                     le32_to_cpu(cl->cl_recs[best].c_free))
1163                         best = curr;
1164                 curr++;
1165         }
1166
1167         BUG_ON(best >= le16_to_cpu(cl->cl_next_free_rec));
1168         return best;
1169 }
1170
1171 static int ocfs2_relink_block_group(handle_t *handle,
1172                                     struct inode *alloc_inode,
1173                                     struct buffer_head *fe_bh,
1174                                     struct buffer_head *bg_bh,
1175                                     struct buffer_head *prev_bg_bh,
1176                                     u16 chain)
1177 {
1178         int status;
1179         /* there is a really tiny chance the journal calls could fail,
1180          * but we wouldn't want inconsistent blocks in *any* case. */
1181         u64 fe_ptr, bg_ptr, prev_bg_ptr;
1182         struct ocfs2_dinode *fe = (struct ocfs2_dinode *) fe_bh->b_data;
1183         struct ocfs2_group_desc *bg = (struct ocfs2_group_desc *) bg_bh->b_data;
1184         struct ocfs2_group_desc *prev_bg = (struct ocfs2_group_desc *) prev_bg_bh->b_data;
1185
1186         /* The caller got these descriptors from
1187          * ocfs2_read_group_descriptor().  Any corruption is a code bug. */
1188         BUG_ON(!OCFS2_IS_VALID_GROUP_DESC(bg));
1189         BUG_ON(!OCFS2_IS_VALID_GROUP_DESC(prev_bg));
1190
1191         mlog(0, "Suballoc %llu, chain %u, move group %llu to top, prev = %llu\n",
1192              (unsigned long long)le64_to_cpu(fe->i_blkno), chain,
1193              (unsigned long long)le64_to_cpu(bg->bg_blkno),
1194              (unsigned long long)le64_to_cpu(prev_bg->bg_blkno));
1195
1196         fe_ptr = le64_to_cpu(fe->id2.i_chain.cl_recs[chain].c_blkno);
1197         bg_ptr = le64_to_cpu(bg->bg_next_group);
1198         prev_bg_ptr = le64_to_cpu(prev_bg->bg_next_group);
1199
1200         status = ocfs2_journal_access_gd(handle, INODE_CACHE(alloc_inode),
1201                                          prev_bg_bh,
1202                                          OCFS2_JOURNAL_ACCESS_WRITE);
1203         if (status < 0) {
1204                 mlog_errno(status);
1205                 goto out_rollback;
1206         }
1207
1208         prev_bg->bg_next_group = bg->bg_next_group;
1209
1210         status = ocfs2_journal_dirty(handle, prev_bg_bh);
1211         if (status < 0) {
1212                 mlog_errno(status);
1213                 goto out_rollback;
1214         }
1215
1216         status = ocfs2_journal_access_gd(handle, INODE_CACHE(alloc_inode),
1217                                          bg_bh, OCFS2_JOURNAL_ACCESS_WRITE);
1218         if (status < 0) {
1219                 mlog_errno(status);
1220                 goto out_rollback;
1221         }
1222
1223         bg->bg_next_group = fe->id2.i_chain.cl_recs[chain].c_blkno;
1224
1225         status = ocfs2_journal_dirty(handle, bg_bh);
1226         if (status < 0) {
1227                 mlog_errno(status);
1228                 goto out_rollback;
1229         }
1230
1231         status = ocfs2_journal_access_di(handle, INODE_CACHE(alloc_inode),
1232                                          fe_bh, OCFS2_JOURNAL_ACCESS_WRITE);
1233         if (status < 0) {
1234                 mlog_errno(status);
1235                 goto out_rollback;
1236         }
1237
1238         fe->id2.i_chain.cl_recs[chain].c_blkno = bg->bg_blkno;
1239
1240         status = ocfs2_journal_dirty(handle, fe_bh);
1241         if (status < 0) {
1242                 mlog_errno(status);
1243                 goto out_rollback;
1244         }
1245
1246         status = 0;
1247 out_rollback:
1248         if (status < 0) {
1249                 fe->id2.i_chain.cl_recs[chain].c_blkno = cpu_to_le64(fe_ptr);
1250                 bg->bg_next_group = cpu_to_le64(bg_ptr);
1251                 prev_bg->bg_next_group = cpu_to_le64(prev_bg_ptr);
1252         }
1253
1254         mlog_exit(status);
1255         return status;
1256 }
1257
1258 static inline int ocfs2_block_group_reasonably_empty(struct ocfs2_group_desc *bg,
1259                                                      u32 wanted)
1260 {
1261         return le16_to_cpu(bg->bg_free_bits_count) > wanted;
1262 }
1263
1264 /* return 0 on success, -ENOSPC to keep searching and any other < 0
1265  * value on error. */
1266 static int ocfs2_cluster_group_search(struct inode *inode,
1267                                       struct buffer_head *group_bh,
1268                                       u32 bits_wanted, u32 min_bits,
1269                                       u64 max_block,
1270                                       u16 *bit_off, u16 *bits_found)
1271 {
1272         int search = -ENOSPC;
1273         int ret;
1274         u64 blkoff;
1275         struct ocfs2_group_desc *gd = (struct ocfs2_group_desc *) group_bh->b_data;
1276         struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
1277         u16 tmp_off, tmp_found;
1278         unsigned int max_bits, gd_cluster_off;
1279
1280         BUG_ON(!ocfs2_is_cluster_bitmap(inode));
1281
1282         if (gd->bg_free_bits_count) {
1283                 max_bits = le16_to_cpu(gd->bg_bits);
1284
1285                 /* Tail groups in cluster bitmaps which aren't cpg
1286                  * aligned are prone to partial extention by a failed
1287                  * fs resize. If the file system resize never got to
1288                  * update the dinode cluster count, then we don't want
1289                  * to trust any clusters past it, regardless of what
1290                  * the group descriptor says. */
1291                 gd_cluster_off = ocfs2_blocks_to_clusters(inode->i_sb,
1292                                                           le64_to_cpu(gd->bg_blkno));
1293                 if ((gd_cluster_off + max_bits) >
1294                     OCFS2_I(inode)->ip_clusters) {
1295                         max_bits = OCFS2_I(inode)->ip_clusters - gd_cluster_off;
1296                         mlog(0, "Desc %llu, bg_bits %u, clusters %u, use %u\n",
1297                              (unsigned long long)le64_to_cpu(gd->bg_blkno),
1298                              le16_to_cpu(gd->bg_bits),
1299                              OCFS2_I(inode)->ip_clusters, max_bits);
1300                 }
1301
1302                 ret = ocfs2_block_group_find_clear_bits(OCFS2_SB(inode->i_sb),
1303                                                         group_bh, bits_wanted,
1304                                                         max_bits,
1305                                                         &tmp_off, &tmp_found);
1306                 if (ret)
1307                         return ret;
1308
1309                 if (max_block) {
1310                         blkoff = ocfs2_clusters_to_blocks(inode->i_sb,
1311                                                           gd_cluster_off +
1312                                                           tmp_off + tmp_found);
1313                         mlog(0, "Checking %llu against %llu\n",
1314                              (unsigned long long)blkoff,
1315                              (unsigned long long)max_block);
1316                         if (blkoff > max_block)
1317                                 return -ENOSPC;
1318                 }
1319
1320                 /* ocfs2_block_group_find_clear_bits() might
1321                  * return success, but we still want to return
1322                  * -ENOSPC unless it found the minimum number
1323                  * of bits. */
1324                 if (min_bits <= tmp_found) {
1325                         *bit_off = tmp_off;
1326                         *bits_found = tmp_found;
1327                         search = 0; /* success */
1328                 } else if (tmp_found) {
1329                         /*
1330                          * Don't show bits which we'll be returning
1331                          * for allocation to the local alloc bitmap.
1332                          */
1333                         ocfs2_local_alloc_seen_free_bits(osb, tmp_found);
1334                 }
1335         }
1336
1337         return search;
1338 }
1339
1340 static int ocfs2_block_group_search(struct inode *inode,
1341                                     struct buffer_head *group_bh,
1342                                     u32 bits_wanted, u32 min_bits,
1343                                     u64 max_block,
1344                                     u16 *bit_off, u16 *bits_found)
1345 {
1346         int ret = -ENOSPC;
1347         u64 blkoff;
1348         struct ocfs2_group_desc *bg = (struct ocfs2_group_desc *) group_bh->b_data;
1349
1350         BUG_ON(min_bits != 1);
1351         BUG_ON(ocfs2_is_cluster_bitmap(inode));
1352
1353         if (bg->bg_free_bits_count) {
1354                 ret = ocfs2_block_group_find_clear_bits(OCFS2_SB(inode->i_sb),
1355                                                         group_bh, bits_wanted,
1356                                                         le16_to_cpu(bg->bg_bits),
1357                                                         bit_off, bits_found);
1358                 if (!ret && max_block) {
1359                         blkoff = le64_to_cpu(bg->bg_blkno) + *bit_off +
1360                                 *bits_found;
1361                         mlog(0, "Checking %llu against %llu\n",
1362                              (unsigned long long)blkoff,
1363                              (unsigned long long)max_block);
1364                         if (blkoff > max_block)
1365                                 ret = -ENOSPC;
1366                 }
1367         }
1368
1369         return ret;
1370 }
1371
1372 static int ocfs2_alloc_dinode_update_counts(struct inode *inode,
1373                                        handle_t *handle,
1374                                        struct buffer_head *di_bh,
1375                                        u32 num_bits,
1376                                        u16 chain)
1377 {
1378         int ret;
1379         u32 tmp_used;
1380         struct ocfs2_dinode *di = (struct ocfs2_dinode *) di_bh->b_data;
1381         struct ocfs2_chain_list *cl = (struct ocfs2_chain_list *) &di->id2.i_chain;
1382
1383         ret = ocfs2_journal_access_di(handle, INODE_CACHE(inode), di_bh,
1384                                       OCFS2_JOURNAL_ACCESS_WRITE);
1385         if (ret < 0) {
1386                 mlog_errno(ret);
1387                 goto out;
1388         }
1389
1390         tmp_used = le32_to_cpu(di->id1.bitmap1.i_used);
1391         di->id1.bitmap1.i_used = cpu_to_le32(num_bits + tmp_used);
1392         le32_add_cpu(&cl->cl_recs[chain].c_free, -num_bits);
1393
1394         ret = ocfs2_journal_dirty(handle, di_bh);
1395         if (ret < 0)
1396                 mlog_errno(ret);
1397
1398 out:
1399         return ret;
1400 }
1401
1402 static int ocfs2_search_one_group(struct ocfs2_alloc_context *ac,
1403                                   handle_t *handle,
1404                                   u32 bits_wanted,
1405                                   u32 min_bits,
1406                                   u16 *bit_off,
1407                                   unsigned int *num_bits,
1408                                   u64 gd_blkno,
1409                                   u16 *bits_left)
1410 {
1411         int ret;
1412         u16 found;
1413         struct buffer_head *group_bh = NULL;
1414         struct ocfs2_group_desc *gd;
1415         struct ocfs2_dinode *di = (struct ocfs2_dinode *)ac->ac_bh->b_data;
1416         struct inode *alloc_inode = ac->ac_inode;
1417
1418         ret = ocfs2_read_group_descriptor(alloc_inode, di, gd_blkno,
1419                                           &group_bh);
1420         if (ret < 0) {
1421                 mlog_errno(ret);
1422                 return ret;
1423         }
1424
1425         gd = (struct ocfs2_group_desc *) group_bh->b_data;
1426         ret = ac->ac_group_search(alloc_inode, group_bh, bits_wanted, min_bits,
1427                                   ac->ac_max_block, bit_off, &found);
1428         if (ret < 0) {
1429                 if (ret != -ENOSPC)
1430                         mlog_errno(ret);
1431                 goto out;
1432         }
1433
1434         *num_bits = found;
1435
1436         ret = ocfs2_alloc_dinode_update_counts(alloc_inode, handle, ac->ac_bh,
1437                                                *num_bits,
1438                                                le16_to_cpu(gd->bg_chain));
1439         if (ret < 0) {
1440                 mlog_errno(ret);
1441                 goto out;
1442         }
1443
1444         ret = ocfs2_block_group_set_bits(handle, alloc_inode, gd, group_bh,
1445                                          *bit_off, *num_bits);
1446         if (ret < 0)
1447                 mlog_errno(ret);
1448
1449         *bits_left = le16_to_cpu(gd->bg_free_bits_count);
1450
1451 out:
1452         brelse(group_bh);
1453
1454         return ret;
1455 }
1456
1457 static int ocfs2_search_chain(struct ocfs2_alloc_context *ac,
1458                               handle_t *handle,
1459                               u32 bits_wanted,
1460                               u32 min_bits,
1461                               u16 *bit_off,
1462                               unsigned int *num_bits,
1463                               u64 *bg_blkno,
1464                               u16 *bits_left)
1465 {
1466         int status;
1467         u16 chain, tmp_bits;
1468         u32 tmp_used;
1469         u64 next_group;
1470         struct inode *alloc_inode = ac->ac_inode;
1471         struct buffer_head *group_bh = NULL;
1472         struct buffer_head *prev_group_bh = NULL;
1473         struct ocfs2_dinode *fe = (struct ocfs2_dinode *) ac->ac_bh->b_data;
1474         struct ocfs2_chain_list *cl = (struct ocfs2_chain_list *) &fe->id2.i_chain;
1475         struct ocfs2_group_desc *bg;
1476
1477         chain = ac->ac_chain;
1478         mlog(0, "trying to alloc %u bits from chain %u, inode %llu\n",
1479              bits_wanted, chain,
1480              (unsigned long long)OCFS2_I(alloc_inode)->ip_blkno);
1481
1482         status = ocfs2_read_group_descriptor(alloc_inode, fe,
1483                                              le64_to_cpu(cl->cl_recs[chain].c_blkno),
1484                                              &group_bh);
1485         if (status < 0) {
1486                 mlog_errno(status);
1487                 goto bail;
1488         }
1489         bg = (struct ocfs2_group_desc *) group_bh->b_data;
1490
1491         status = -ENOSPC;
1492         /* for now, the chain search is a bit simplistic. We just use
1493          * the 1st group with any empty bits. */
1494         while ((status = ac->ac_group_search(alloc_inode, group_bh,
1495                                              bits_wanted, min_bits,
1496                                              ac->ac_max_block, bit_off,
1497                                              &tmp_bits)) == -ENOSPC) {
1498                 if (!bg->bg_next_group)
1499                         break;
1500
1501                 brelse(prev_group_bh);
1502                 prev_group_bh = NULL;
1503
1504                 next_group = le64_to_cpu(bg->bg_next_group);
1505                 prev_group_bh = group_bh;
1506                 group_bh = NULL;
1507                 status = ocfs2_read_group_descriptor(alloc_inode, fe,
1508                                                      next_group, &group_bh);
1509                 if (status < 0) {
1510                         mlog_errno(status);
1511                         goto bail;
1512                 }
1513                 bg = (struct ocfs2_group_desc *) group_bh->b_data;
1514         }
1515         if (status < 0) {
1516                 if (status != -ENOSPC)
1517                         mlog_errno(status);
1518                 goto bail;
1519         }
1520
1521         mlog(0, "alloc succeeds: we give %u bits from block group %llu\n",
1522              tmp_bits, (unsigned long long)le64_to_cpu(bg->bg_blkno));
1523
1524         *num_bits = tmp_bits;
1525
1526         BUG_ON(*num_bits == 0);
1527
1528         /*
1529          * Keep track of previous block descriptor read. When
1530          * we find a target, if we have read more than X
1531          * number of descriptors, and the target is reasonably
1532          * empty, relink him to top of his chain.
1533          *
1534          * We've read 0 extra blocks and only send one more to
1535          * the transaction, yet the next guy to search has a
1536          * much easier time.
1537          *
1538          * Do this *after* figuring out how many bits we're taking out
1539          * of our target group.
1540          */
1541         if (ac->ac_allow_chain_relink &&
1542             (prev_group_bh) &&
1543             (ocfs2_block_group_reasonably_empty(bg, *num_bits))) {
1544                 status = ocfs2_relink_block_group(handle, alloc_inode,
1545                                                   ac->ac_bh, group_bh,
1546                                                   prev_group_bh, chain);
1547                 if (status < 0) {
1548                         mlog_errno(status);
1549                         goto bail;
1550                 }
1551         }
1552
1553         /* Ok, claim our bits now: set the info on dinode, chainlist
1554          * and then the group */
1555         status = ocfs2_journal_access_di(handle,
1556                                          INODE_CACHE(alloc_inode),
1557                                          ac->ac_bh,
1558                                          OCFS2_JOURNAL_ACCESS_WRITE);
1559         if (status < 0) {
1560                 mlog_errno(status);
1561                 goto bail;
1562         }
1563
1564         tmp_used = le32_to_cpu(fe->id1.bitmap1.i_used);
1565         fe->id1.bitmap1.i_used = cpu_to_le32(*num_bits + tmp_used);
1566         le32_add_cpu(&cl->cl_recs[chain].c_free, -(*num_bits));
1567
1568         status = ocfs2_journal_dirty(handle,
1569                                      ac->ac_bh);
1570         if (status < 0) {
1571                 mlog_errno(status);
1572                 goto bail;
1573         }
1574
1575         status = ocfs2_block_group_set_bits(handle,
1576                                             alloc_inode,
1577                                             bg,
1578                                             group_bh,
1579                                             *bit_off,
1580                                             *num_bits);
1581         if (status < 0) {
1582                 mlog_errno(status);
1583                 goto bail;
1584         }
1585
1586         mlog(0, "Allocated %u bits from suballocator %llu\n", *num_bits,
1587              (unsigned long long)le64_to_cpu(fe->i_blkno));
1588
1589         *bg_blkno = le64_to_cpu(bg->bg_blkno);
1590         *bits_left = le16_to_cpu(bg->bg_free_bits_count);
1591 bail:
1592         brelse(group_bh);
1593         brelse(prev_group_bh);
1594
1595         mlog_exit(status);
1596         return status;
1597 }
1598
1599 /* will give out up to bits_wanted contiguous bits. */
1600 static int ocfs2_claim_suballoc_bits(struct ocfs2_super *osb,
1601                                      struct ocfs2_alloc_context *ac,
1602                                      handle_t *handle,
1603                                      u32 bits_wanted,
1604                                      u32 min_bits,
1605                                      u16 *bit_off,
1606                                      unsigned int *num_bits,
1607                                      u64 *bg_blkno)
1608 {
1609         int status;
1610         u16 victim, i;
1611         u16 bits_left = 0;
1612         u64 hint_blkno = ac->ac_last_group;
1613         struct ocfs2_chain_list *cl;
1614         struct ocfs2_dinode *fe;
1615
1616         mlog_entry_void();
1617
1618         BUG_ON(ac->ac_bits_given >= ac->ac_bits_wanted);
1619         BUG_ON(bits_wanted > (ac->ac_bits_wanted - ac->ac_bits_given));
1620         BUG_ON(!ac->ac_bh);
1621
1622         fe = (struct ocfs2_dinode *) ac->ac_bh->b_data;
1623
1624         /* The bh was validated by the inode read during
1625          * ocfs2_reserve_suballoc_bits().  Any corruption is a code bug. */
1626         BUG_ON(!OCFS2_IS_VALID_DINODE(fe));
1627
1628         if (le32_to_cpu(fe->id1.bitmap1.i_used) >=
1629             le32_to_cpu(fe->id1.bitmap1.i_total)) {
1630                 ocfs2_error(osb->sb, "Chain allocator dinode %llu has %u used "
1631                             "bits but only %u total.",
1632                             (unsigned long long)le64_to_cpu(fe->i_blkno),
1633                             le32_to_cpu(fe->id1.bitmap1.i_used),
1634                             le32_to_cpu(fe->id1.bitmap1.i_total));
1635                 status = -EIO;
1636                 goto bail;
1637         }
1638
1639         if (hint_blkno) {
1640                 /* Attempt to short-circuit the usual search mechanism
1641                  * by jumping straight to the most recently used
1642                  * allocation group. This helps us mantain some
1643                  * contiguousness across allocations. */
1644                 status = ocfs2_search_one_group(ac, handle, bits_wanted,
1645                                                 min_bits, bit_off, num_bits,
1646                                                 hint_blkno, &bits_left);
1647                 if (!status) {
1648                         /* Be careful to update *bg_blkno here as the
1649                          * caller is expecting it to be filled in, and
1650                          * ocfs2_search_one_group() won't do that for
1651                          * us. */
1652                         *bg_blkno = hint_blkno;
1653                         goto set_hint;
1654                 }
1655                 if (status < 0 && status != -ENOSPC) {
1656                         mlog_errno(status);
1657                         goto bail;
1658                 }
1659         }
1660
1661         cl = (struct ocfs2_chain_list *) &fe->id2.i_chain;
1662
1663         victim = ocfs2_find_victim_chain(cl);
1664         ac->ac_chain = victim;
1665         ac->ac_allow_chain_relink = 1;
1666
1667         status = ocfs2_search_chain(ac, handle, bits_wanted, min_bits, bit_off,
1668                                     num_bits, bg_blkno, &bits_left);
1669         if (!status)
1670                 goto set_hint;
1671         if (status < 0 && status != -ENOSPC) {
1672                 mlog_errno(status);
1673                 goto bail;
1674         }
1675
1676         mlog(0, "Search of victim chain %u came up with nothing, "
1677              "trying all chains now.\n", victim);
1678
1679         /* If we didn't pick a good victim, then just default to
1680          * searching each chain in order. Don't allow chain relinking
1681          * because we only calculate enough journal credits for one
1682          * relink per alloc. */
1683         ac->ac_allow_chain_relink = 0;
1684         for (i = 0; i < le16_to_cpu(cl->cl_next_free_rec); i ++) {
1685                 if (i == victim)
1686                         continue;
1687                 if (!cl->cl_recs[i].c_free)
1688                         continue;
1689
1690                 ac->ac_chain = i;
1691                 status = ocfs2_search_chain(ac, handle, bits_wanted, min_bits,
1692                                             bit_off, num_bits, bg_blkno,
1693                                             &bits_left);
1694                 if (!status)
1695                         break;
1696                 if (status < 0 && status != -ENOSPC) {
1697                         mlog_errno(status);
1698                         goto bail;
1699                 }
1700         }
1701
1702 set_hint:
1703         if (status != -ENOSPC) {
1704                 /* If the next search of this group is not likely to
1705                  * yield a suitable extent, then we reset the last
1706                  * group hint so as to not waste a disk read */
1707                 if (bits_left < min_bits)
1708                         ac->ac_last_group = 0;
1709                 else
1710                         ac->ac_last_group = *bg_blkno;
1711         }
1712
1713 bail:
1714         mlog_exit(status);
1715         return status;
1716 }
1717
1718 int ocfs2_claim_metadata(struct ocfs2_super *osb,
1719                          handle_t *handle,
1720                          struct ocfs2_alloc_context *ac,
1721                          u32 bits_wanted,
1722                          u16 *suballoc_bit_start,
1723                          unsigned int *num_bits,
1724                          u64 *blkno_start)
1725 {
1726         int status;
1727         u64 bg_blkno;
1728
1729         BUG_ON(!ac);
1730         BUG_ON(ac->ac_bits_wanted < (ac->ac_bits_given + bits_wanted));
1731         BUG_ON(ac->ac_which != OCFS2_AC_USE_META);
1732
1733         status = ocfs2_claim_suballoc_bits(osb,
1734                                            ac,
1735                                            handle,
1736                                            bits_wanted,
1737                                            1,
1738                                            suballoc_bit_start,
1739                                            num_bits,
1740                                            &bg_blkno);
1741         if (status < 0) {
1742                 mlog_errno(status);
1743                 goto bail;
1744         }
1745         atomic_inc(&osb->alloc_stats.bg_allocs);
1746
1747         *blkno_start = bg_blkno + (u64) *suballoc_bit_start;
1748         ac->ac_bits_given += (*num_bits);
1749         status = 0;
1750 bail:
1751         mlog_exit(status);
1752         return status;
1753 }
1754
1755 static void ocfs2_init_inode_ac_group(struct inode *dir,
1756                                       struct buffer_head *parent_fe_bh,
1757                                       struct ocfs2_alloc_context *ac)
1758 {
1759         struct ocfs2_dinode *fe = (struct ocfs2_dinode *)parent_fe_bh->b_data;
1760         /*
1761          * Try to allocate inodes from some specific group.
1762          *
1763          * If the parent dir has recorded the last group used in allocation,
1764          * cool, use it. Otherwise if we try to allocate new inode from the
1765          * same slot the parent dir belongs to, use the same chunk.
1766          *
1767          * We are very careful here to avoid the mistake of setting
1768          * ac_last_group to a group descriptor from a different (unlocked) slot.
1769          */
1770         if (OCFS2_I(dir)->ip_last_used_group &&
1771             OCFS2_I(dir)->ip_last_used_slot == ac->ac_alloc_slot)
1772                 ac->ac_last_group = OCFS2_I(dir)->ip_last_used_group;
1773         else if (le16_to_cpu(fe->i_suballoc_slot) == ac->ac_alloc_slot)
1774                 ac->ac_last_group = ocfs2_which_suballoc_group(
1775                                         le64_to_cpu(fe->i_blkno),
1776                                         le16_to_cpu(fe->i_suballoc_bit));
1777 }
1778
1779 static inline void ocfs2_save_inode_ac_group(struct inode *dir,
1780                                              struct ocfs2_alloc_context *ac)
1781 {
1782         OCFS2_I(dir)->ip_last_used_group = ac->ac_last_group;
1783         OCFS2_I(dir)->ip_last_used_slot = ac->ac_alloc_slot;
1784 }
1785
1786 int ocfs2_claim_new_inode(struct ocfs2_super *osb,
1787                           handle_t *handle,
1788                           struct inode *dir,
1789                           struct buffer_head *parent_fe_bh,
1790                           struct ocfs2_alloc_context *ac,
1791                           u16 *suballoc_bit,
1792                           u64 *fe_blkno)
1793 {
1794         int status;
1795         unsigned int num_bits;
1796         u64 bg_blkno;
1797
1798         mlog_entry_void();
1799
1800         BUG_ON(!ac);
1801         BUG_ON(ac->ac_bits_given != 0);
1802         BUG_ON(ac->ac_bits_wanted != 1);
1803         BUG_ON(ac->ac_which != OCFS2_AC_USE_INODE);
1804
1805         ocfs2_init_inode_ac_group(dir, parent_fe_bh, ac);
1806
1807         status = ocfs2_claim_suballoc_bits(osb,
1808                                            ac,
1809                                            handle,
1810                                            1,
1811                                            1,
1812                                            suballoc_bit,
1813                                            &num_bits,
1814                                            &bg_blkno);
1815         if (status < 0) {
1816                 mlog_errno(status);
1817                 goto bail;
1818         }
1819         atomic_inc(&osb->alloc_stats.bg_allocs);
1820
1821         BUG_ON(num_bits != 1);
1822
1823         *fe_blkno = bg_blkno + (u64) (*suballoc_bit);
1824         ac->ac_bits_given++;
1825         ocfs2_save_inode_ac_group(dir, ac);
1826         status = 0;
1827 bail:
1828         mlog_exit(status);
1829         return status;
1830 }
1831
1832 /* translate a group desc. blkno and it's bitmap offset into
1833  * disk cluster offset. */
1834 static inline u32 ocfs2_desc_bitmap_to_cluster_off(struct inode *inode,
1835                                                    u64 bg_blkno,
1836                                                    u16 bg_bit_off)
1837 {
1838         struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
1839         u32 cluster = 0;
1840
1841         BUG_ON(!ocfs2_is_cluster_bitmap(inode));
1842
1843         if (bg_blkno != osb->first_cluster_group_blkno)
1844                 cluster = ocfs2_blocks_to_clusters(inode->i_sb, bg_blkno);
1845         cluster += (u32) bg_bit_off;
1846         return cluster;
1847 }
1848
1849 /* given a cluster offset, calculate which block group it belongs to
1850  * and return that block offset. */
1851 u64 ocfs2_which_cluster_group(struct inode *inode, u32 cluster)
1852 {
1853         struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
1854         u32 group_no;
1855
1856         BUG_ON(!ocfs2_is_cluster_bitmap(inode));
1857
1858         group_no = cluster / osb->bitmap_cpg;
1859         if (!group_no)
1860                 return osb->first_cluster_group_blkno;
1861         return ocfs2_clusters_to_blocks(inode->i_sb,
1862                                         group_no * osb->bitmap_cpg);
1863 }
1864
1865 /* given the block number of a cluster start, calculate which cluster
1866  * group and descriptor bitmap offset that corresponds to. */
1867 static inline void ocfs2_block_to_cluster_group(struct inode *inode,
1868                                                 u64 data_blkno,
1869                                                 u64 *bg_blkno,
1870                                                 u16 *bg_bit_off)
1871 {
1872         struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
1873         u32 data_cluster = ocfs2_blocks_to_clusters(osb->sb, data_blkno);
1874
1875         BUG_ON(!ocfs2_is_cluster_bitmap(inode));
1876
1877         *bg_blkno = ocfs2_which_cluster_group(inode,
1878                                               data_cluster);
1879
1880         if (*bg_blkno == osb->first_cluster_group_blkno)
1881                 *bg_bit_off = (u16) data_cluster;
1882         else
1883                 *bg_bit_off = (u16) ocfs2_blocks_to_clusters(osb->sb,
1884                                                              data_blkno - *bg_blkno);
1885 }
1886
1887 /*
1888  * min_bits - minimum contiguous chunk from this total allocation we
1889  * can handle. set to what we asked for originally for a full
1890  * contig. allocation, set to '1' to indicate we can deal with extents
1891  * of any size.
1892  */
1893 int __ocfs2_claim_clusters(struct ocfs2_super *osb,
1894                            handle_t *handle,
1895                            struct ocfs2_alloc_context *ac,
1896                            u32 min_clusters,
1897                            u32 max_clusters,
1898                            u32 *cluster_start,
1899                            u32 *num_clusters)
1900 {
1901         int status;
1902         unsigned int bits_wanted = max_clusters;
1903         u64 bg_blkno = 0;
1904         u16 bg_bit_off;
1905
1906         mlog_entry_void();
1907
1908         BUG_ON(ac->ac_bits_given >= ac->ac_bits_wanted);
1909
1910         BUG_ON(ac->ac_which != OCFS2_AC_USE_LOCAL
1911                && ac->ac_which != OCFS2_AC_USE_MAIN);
1912
1913         if (ac->ac_which == OCFS2_AC_USE_LOCAL) {
1914                 status = ocfs2_claim_local_alloc_bits(osb,
1915                                                       handle,
1916                                                       ac,
1917                                                       bits_wanted,
1918                                                       cluster_start,
1919                                                       num_clusters);
1920                 if (!status)
1921                         atomic_inc(&osb->alloc_stats.local_data);
1922         } else {
1923                 if (min_clusters > (osb->bitmap_cpg - 1)) {
1924                         /* The only paths asking for contiguousness
1925                          * should know about this already. */
1926                         mlog(ML_ERROR, "minimum allocation requested %u exceeds "
1927                              "group bitmap size %u!\n", min_clusters,
1928                              osb->bitmap_cpg);
1929                         status = -ENOSPC;
1930                         goto bail;
1931                 }
1932                 /* clamp the current request down to a realistic size. */
1933                 if (bits_wanted > (osb->bitmap_cpg - 1))
1934                         bits_wanted = osb->bitmap_cpg - 1;
1935
1936                 status = ocfs2_claim_suballoc_bits(osb,
1937                                                    ac,
1938                                                    handle,
1939                                                    bits_wanted,
1940                                                    min_clusters,
1941                                                    &bg_bit_off,
1942                                                    num_clusters,
1943                                                    &bg_blkno);
1944                 if (!status) {
1945                         *cluster_start =
1946                                 ocfs2_desc_bitmap_to_cluster_off(ac->ac_inode,
1947                                                                  bg_blkno,
1948                                                                  bg_bit_off);
1949                         atomic_inc(&osb->alloc_stats.bitmap_data);
1950                 }
1951         }
1952         if (status < 0) {
1953                 if (status != -ENOSPC)
1954                         mlog_errno(status);
1955                 goto bail;
1956         }
1957
1958         ac->ac_bits_given += *num_clusters;
1959
1960 bail:
1961         mlog_exit(status);
1962         return status;
1963 }
1964
1965 int ocfs2_claim_clusters(struct ocfs2_super *osb,
1966                          handle_t *handle,
1967                          struct ocfs2_alloc_context *ac,
1968                          u32 min_clusters,
1969                          u32 *cluster_start,
1970                          u32 *num_clusters)
1971 {
1972         unsigned int bits_wanted = ac->ac_bits_wanted - ac->ac_bits_given;
1973
1974         return __ocfs2_claim_clusters(osb, handle, ac, min_clusters,
1975                                       bits_wanted, cluster_start, num_clusters);
1976 }
1977
1978 static inline int ocfs2_block_group_clear_bits(handle_t *handle,
1979                                                struct inode *alloc_inode,
1980                                                struct ocfs2_group_desc *bg,
1981                                                struct buffer_head *group_bh,
1982                                                unsigned int bit_off,
1983                                                unsigned int num_bits)
1984 {
1985         int status;
1986         unsigned int tmp;
1987         int journal_type = OCFS2_JOURNAL_ACCESS_WRITE;
1988         struct ocfs2_group_desc *undo_bg = NULL;
1989         int cluster_bitmap = 0;
1990
1991         mlog_entry_void();
1992
1993         /* The caller got this descriptor from
1994          * ocfs2_read_group_descriptor().  Any corruption is a code bug. */
1995         BUG_ON(!OCFS2_IS_VALID_GROUP_DESC(bg));
1996
1997         mlog(0, "off = %u, num = %u\n", bit_off, num_bits);
1998
1999         if (ocfs2_is_cluster_bitmap(alloc_inode))
2000                 journal_type = OCFS2_JOURNAL_ACCESS_UNDO;
2001
2002         status = ocfs2_journal_access_gd(handle, INODE_CACHE(alloc_inode),
2003                                          group_bh, journal_type);
2004         if (status < 0) {
2005                 mlog_errno(status);
2006                 goto bail;
2007         }
2008
2009         if (ocfs2_is_cluster_bitmap(alloc_inode))
2010                 cluster_bitmap = 1;
2011
2012         if (cluster_bitmap) {
2013                 jbd_lock_bh_state(group_bh);
2014                 undo_bg = (struct ocfs2_group_desc *)
2015                                         bh2jh(group_bh)->b_committed_data;
2016                 BUG_ON(!undo_bg);
2017         }
2018
2019         tmp = num_bits;
2020         while(tmp--) {
2021                 ocfs2_clear_bit((bit_off + tmp),
2022                                 (unsigned long *) bg->bg_bitmap);
2023                 if (cluster_bitmap)
2024                         ocfs2_set_bit(bit_off + tmp,
2025                                       (unsigned long *) undo_bg->bg_bitmap);
2026         }
2027         le16_add_cpu(&bg->bg_free_bits_count, num_bits);
2028
2029         if (cluster_bitmap)
2030                 jbd_unlock_bh_state(group_bh);
2031
2032         status = ocfs2_journal_dirty(handle, group_bh);
2033         if (status < 0)
2034                 mlog_errno(status);
2035 bail:
2036         return status;
2037 }
2038
2039 /*
2040  * expects the suballoc inode to already be locked.
2041  */
2042 int ocfs2_free_suballoc_bits(handle_t *handle,
2043                              struct inode *alloc_inode,
2044                              struct buffer_head *alloc_bh,
2045                              unsigned int start_bit,
2046                              u64 bg_blkno,
2047                              unsigned int count)
2048 {
2049         int status = 0;
2050         u32 tmp_used;
2051         struct ocfs2_dinode *fe = (struct ocfs2_dinode *) alloc_bh->b_data;
2052         struct ocfs2_chain_list *cl = &fe->id2.i_chain;
2053         struct buffer_head *group_bh = NULL;
2054         struct ocfs2_group_desc *group;
2055
2056         mlog_entry_void();
2057
2058         /* The alloc_bh comes from ocfs2_free_dinode() or
2059          * ocfs2_free_clusters().  The callers have all locked the
2060          * allocator and gotten alloc_bh from the lock call.  This
2061          * validates the dinode buffer.  Any corruption that has happended
2062          * is a code bug. */
2063         BUG_ON(!OCFS2_IS_VALID_DINODE(fe));
2064         BUG_ON((count + start_bit) > ocfs2_bits_per_group(cl));
2065
2066         mlog(0, "%llu: freeing %u bits from group %llu, starting at %u\n",
2067              (unsigned long long)OCFS2_I(alloc_inode)->ip_blkno, count,
2068              (unsigned long long)bg_blkno, start_bit);
2069
2070         status = ocfs2_read_group_descriptor(alloc_inode, fe, bg_blkno,
2071                                              &group_bh);
2072         if (status < 0) {
2073                 mlog_errno(status);
2074                 goto bail;
2075         }
2076         group = (struct ocfs2_group_desc *) group_bh->b_data;
2077
2078         BUG_ON((count + start_bit) > le16_to_cpu(group->bg_bits));
2079
2080         status = ocfs2_block_group_clear_bits(handle, alloc_inode,
2081                                               group, group_bh,
2082                                               start_bit, count);
2083         if (status < 0) {
2084                 mlog_errno(status);
2085                 goto bail;
2086         }
2087
2088         status = ocfs2_journal_access_di(handle, INODE_CACHE(alloc_inode),
2089                                          alloc_bh, OCFS2_JOURNAL_ACCESS_WRITE);
2090         if (status < 0) {
2091                 mlog_errno(status);
2092                 goto bail;
2093         }
2094
2095         le32_add_cpu(&cl->cl_recs[le16_to_cpu(group->bg_chain)].c_free,
2096                      count);
2097         tmp_used = le32_to_cpu(fe->id1.bitmap1.i_used);
2098         fe->id1.bitmap1.i_used = cpu_to_le32(tmp_used - count);
2099
2100         status = ocfs2_journal_dirty(handle, alloc_bh);
2101         if (status < 0) {
2102                 mlog_errno(status);
2103                 goto bail;
2104         }
2105
2106 bail:
2107         brelse(group_bh);
2108
2109         mlog_exit(status);
2110         return status;
2111 }
2112
2113 int ocfs2_free_dinode(handle_t *handle,
2114                       struct inode *inode_alloc_inode,
2115                       struct buffer_head *inode_alloc_bh,
2116                       struct ocfs2_dinode *di)
2117 {
2118         u64 blk = le64_to_cpu(di->i_blkno);
2119         u16 bit = le16_to_cpu(di->i_suballoc_bit);
2120         u64 bg_blkno = ocfs2_which_suballoc_group(blk, bit);
2121
2122         return ocfs2_free_suballoc_bits(handle, inode_alloc_inode,
2123                                         inode_alloc_bh, bit, bg_blkno, 1);
2124 }
2125
2126 int ocfs2_free_clusters(handle_t *handle,
2127                        struct inode *bitmap_inode,
2128                        struct buffer_head *bitmap_bh,
2129                        u64 start_blk,
2130                        unsigned int num_clusters)
2131 {
2132         int status;
2133         u16 bg_start_bit;
2134         u64 bg_blkno;
2135         struct ocfs2_dinode *fe;
2136
2137         /* You can't ever have a contiguous set of clusters
2138          * bigger than a block group bitmap so we never have to worry
2139          * about looping on them. */
2140
2141         mlog_entry_void();
2142
2143         /* This is expensive. We can safely remove once this stuff has
2144          * gotten tested really well. */
2145         BUG_ON(start_blk != ocfs2_clusters_to_blocks(bitmap_inode->i_sb, ocfs2_blocks_to_clusters(bitmap_inode->i_sb, start_blk)));
2146
2147         fe = (struct ocfs2_dinode *) bitmap_bh->b_data;
2148
2149         ocfs2_block_to_cluster_group(bitmap_inode, start_blk, &bg_blkno,
2150                                      &bg_start_bit);
2151
2152         mlog(0, "want to free %u clusters starting at block %llu\n",
2153              num_clusters, (unsigned long long)start_blk);
2154         mlog(0, "bg_blkno = %llu, bg_start_bit = %u\n",
2155              (unsigned long long)bg_blkno, bg_start_bit);
2156
2157         status = ocfs2_free_suballoc_bits(handle, bitmap_inode, bitmap_bh,
2158                                           bg_start_bit, bg_blkno,
2159                                           num_clusters);
2160         if (status < 0) {
2161                 mlog_errno(status);
2162                 goto out;
2163         }
2164
2165         ocfs2_local_alloc_seen_free_bits(OCFS2_SB(bitmap_inode->i_sb),
2166                                          num_clusters);
2167
2168 out:
2169         mlog_exit(status);
2170         return status;
2171 }
2172
2173 static inline void ocfs2_debug_bg(struct ocfs2_group_desc *bg)
2174 {
2175         printk("Block Group:\n");
2176         printk("bg_signature:       %s\n", bg->bg_signature);
2177         printk("bg_size:            %u\n", bg->bg_size);
2178         printk("bg_bits:            %u\n", bg->bg_bits);
2179         printk("bg_free_bits_count: %u\n", bg->bg_free_bits_count);
2180         printk("bg_chain:           %u\n", bg->bg_chain);
2181         printk("bg_generation:      %u\n", le32_to_cpu(bg->bg_generation));
2182         printk("bg_next_group:      %llu\n",
2183                (unsigned long long)bg->bg_next_group);
2184         printk("bg_parent_dinode:   %llu\n",
2185                (unsigned long long)bg->bg_parent_dinode);
2186         printk("bg_blkno:           %llu\n",
2187                (unsigned long long)bg->bg_blkno);
2188 }
2189
2190 static inline void ocfs2_debug_suballoc_inode(struct ocfs2_dinode *fe)
2191 {
2192         int i;
2193
2194         printk("Suballoc Inode %llu:\n", (unsigned long long)fe->i_blkno);
2195         printk("i_signature:                  %s\n", fe->i_signature);
2196         printk("i_size:                       %llu\n",
2197                (unsigned long long)fe->i_size);
2198         printk("i_clusters:                   %u\n", fe->i_clusters);
2199         printk("i_generation:                 %u\n",
2200                le32_to_cpu(fe->i_generation));
2201         printk("id1.bitmap1.i_used:           %u\n",
2202                le32_to_cpu(fe->id1.bitmap1.i_used));
2203         printk("id1.bitmap1.i_total:          %u\n",
2204                le32_to_cpu(fe->id1.bitmap1.i_total));
2205         printk("id2.i_chain.cl_cpg:           %u\n", fe->id2.i_chain.cl_cpg);
2206         printk("id2.i_chain.cl_bpc:           %u\n", fe->id2.i_chain.cl_bpc);
2207         printk("id2.i_chain.cl_count:         %u\n", fe->id2.i_chain.cl_count);
2208         printk("id2.i_chain.cl_next_free_rec: %u\n",
2209                fe->id2.i_chain.cl_next_free_rec);
2210         for(i = 0; i < fe->id2.i_chain.cl_next_free_rec; i++) {
2211                 printk("fe->id2.i_chain.cl_recs[%d].c_free:  %u\n", i,
2212                        fe->id2.i_chain.cl_recs[i].c_free);
2213                 printk("fe->id2.i_chain.cl_recs[%d].c_total: %u\n", i,
2214                        fe->id2.i_chain.cl_recs[i].c_total);
2215                 printk("fe->id2.i_chain.cl_recs[%d].c_blkno: %llu\n", i,
2216                        (unsigned long long)fe->id2.i_chain.cl_recs[i].c_blkno);
2217         }
2218 }
2219
2220 /*
2221  * For a given allocation, determine which allocators will need to be
2222  * accessed, and lock them, reserving the appropriate number of bits.
2223  *
2224  * Sparse file systems call this from ocfs2_write_begin_nolock()
2225  * and ocfs2_allocate_unwritten_extents().
2226  *
2227  * File systems which don't support holes call this from
2228  * ocfs2_extend_allocation().
2229  */
2230 int ocfs2_lock_allocators(struct inode *inode,
2231                           struct ocfs2_extent_tree *et,
2232                           u32 clusters_to_add, u32 extents_to_split,
2233                           struct ocfs2_alloc_context **data_ac,
2234                           struct ocfs2_alloc_context **meta_ac)
2235 {
2236         int ret = 0, num_free_extents;
2237         unsigned int max_recs_needed = clusters_to_add + 2 * extents_to_split;
2238         struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
2239
2240         *meta_ac = NULL;
2241         if (data_ac)
2242                 *data_ac = NULL;
2243
2244         BUG_ON(clusters_to_add != 0 && data_ac == NULL);
2245
2246         num_free_extents = ocfs2_num_free_extents(osb, et);
2247         if (num_free_extents < 0) {
2248                 ret = num_free_extents;
2249                 mlog_errno(ret);
2250                 goto out;
2251         }
2252
2253         /*
2254          * Sparse allocation file systems need to be more conservative
2255          * with reserving room for expansion - the actual allocation
2256          * happens while we've got a journal handle open so re-taking
2257          * a cluster lock (because we ran out of room for another
2258          * extent) will violate ordering rules.
2259          *
2260          * Most of the time we'll only be seeing this 1 cluster at a time
2261          * anyway.
2262          *
2263          * Always lock for any unwritten extents - we might want to
2264          * add blocks during a split.
2265          */
2266         if (!num_free_extents ||
2267             (ocfs2_sparse_alloc(osb) && num_free_extents < max_recs_needed)) {
2268                 ret = ocfs2_reserve_new_metadata(osb, et->et_root_el, meta_ac);
2269                 if (ret < 0) {
2270                         if (ret != -ENOSPC)
2271                                 mlog_errno(ret);
2272                         goto out;
2273                 }
2274         }
2275
2276         if (clusters_to_add == 0)
2277                 goto out;
2278
2279         ret = ocfs2_reserve_clusters(osb, clusters_to_add, data_ac);
2280         if (ret < 0) {
2281                 if (ret != -ENOSPC)
2282                         mlog_errno(ret);
2283                 goto out;
2284         }
2285
2286 out:
2287         if (ret) {
2288                 if (*meta_ac) {
2289                         ocfs2_free_alloc_context(*meta_ac);
2290                         *meta_ac = NULL;
2291                 }
2292
2293                 /*
2294                  * We cannot have an error and a non null *data_ac.
2295                  */
2296         }
2297
2298         return ret;
2299 }
2300
2301 /*
2302  * Read the inode specified by blkno to get suballoc_slot and
2303  * suballoc_bit.
2304  */
2305 static int ocfs2_get_suballoc_slot_bit(struct ocfs2_super *osb, u64 blkno,
2306                                        u16 *suballoc_slot, u16 *suballoc_bit)
2307 {
2308         int status;
2309         struct buffer_head *inode_bh = NULL;
2310         struct ocfs2_dinode *inode_fe;
2311
2312         mlog_entry("blkno: %llu\n", (unsigned long long)blkno);
2313
2314         /* dirty read disk */
2315         status = ocfs2_read_blocks_sync(osb, blkno, 1, &inode_bh);
2316         if (status < 0) {
2317                 mlog(ML_ERROR, "read block %llu failed %d\n",
2318                      (unsigned long long)blkno, status);
2319                 goto bail;
2320         }
2321
2322         inode_fe = (struct ocfs2_dinode *) inode_bh->b_data;
2323         if (!OCFS2_IS_VALID_DINODE(inode_fe)) {
2324                 mlog(ML_ERROR, "invalid inode %llu requested\n",
2325                      (unsigned long long)blkno);
2326                 status = -EINVAL;
2327                 goto bail;
2328         }
2329
2330         if (le16_to_cpu(inode_fe->i_suballoc_slot) != (u16)OCFS2_INVALID_SLOT &&
2331             (u32)le16_to_cpu(inode_fe->i_suballoc_slot) > osb->max_slots - 1) {
2332                 mlog(ML_ERROR, "inode %llu has invalid suballoc slot %u\n",
2333                      (unsigned long long)blkno,
2334                      (u32)le16_to_cpu(inode_fe->i_suballoc_slot));
2335                 status = -EINVAL;
2336                 goto bail;
2337         }
2338
2339         if (suballoc_slot)
2340                 *suballoc_slot = le16_to_cpu(inode_fe->i_suballoc_slot);
2341         if (suballoc_bit)
2342                 *suballoc_bit = le16_to_cpu(inode_fe->i_suballoc_bit);
2343
2344 bail:
2345         brelse(inode_bh);
2346
2347         mlog_exit(status);
2348         return status;
2349 }
2350
2351 /*
2352  * test whether bit is SET in allocator bitmap or not.  on success, 0
2353  * is returned and *res is 1 for SET; 0 otherwise.  when fails, errno
2354  * is returned and *res is meaningless.  Call this after you have
2355  * cluster locked against suballoc, or you may get a result based on
2356  * non-up2date contents
2357  */
2358 static int ocfs2_test_suballoc_bit(struct ocfs2_super *osb,
2359                                    struct inode *suballoc,
2360                                    struct buffer_head *alloc_bh, u64 blkno,
2361                                    u16 bit, int *res)
2362 {
2363         struct ocfs2_dinode *alloc_fe;
2364         struct ocfs2_group_desc *group;
2365         struct buffer_head *group_bh = NULL;
2366         u64 bg_blkno;
2367         int status;
2368
2369         mlog_entry("blkno: %llu bit: %u\n", (unsigned long long)blkno,
2370                    (unsigned int)bit);
2371
2372         alloc_fe = (struct ocfs2_dinode *)alloc_bh->b_data;
2373         if ((bit + 1) > ocfs2_bits_per_group(&alloc_fe->id2.i_chain)) {
2374                 mlog(ML_ERROR, "suballoc bit %u out of range of %u\n",
2375                      (unsigned int)bit,
2376                      ocfs2_bits_per_group(&alloc_fe->id2.i_chain));
2377                 status = -EINVAL;
2378                 goto bail;
2379         }
2380
2381         bg_blkno = ocfs2_which_suballoc_group(blkno, bit);
2382         status = ocfs2_read_group_descriptor(suballoc, alloc_fe, bg_blkno,
2383                                              &group_bh);
2384         if (status < 0) {
2385                 mlog(ML_ERROR, "read group %llu failed %d\n",
2386                      (unsigned long long)bg_blkno, status);
2387                 goto bail;
2388         }
2389
2390         group = (struct ocfs2_group_desc *) group_bh->b_data;
2391         *res = ocfs2_test_bit(bit, (unsigned long *)group->bg_bitmap);
2392
2393 bail:
2394         brelse(group_bh);
2395
2396         mlog_exit(status);
2397         return status;
2398 }
2399
2400 /*
2401  * Test if the bit representing this inode (blkno) is set in the
2402  * suballocator.
2403  *
2404  * On success, 0 is returned and *res is 1 for SET; 0 otherwise.
2405  *
2406  * In the event of failure, a negative value is returned and *res is
2407  * meaningless.
2408  *
2409  * Callers must make sure to hold nfs_sync_lock to prevent
2410  * ocfs2_delete_inode() on another node from accessing the same
2411  * suballocator concurrently.
2412  */
2413 int ocfs2_test_inode_bit(struct ocfs2_super *osb, u64 blkno, int *res)
2414 {
2415         int status;
2416         u16 suballoc_bit = 0, suballoc_slot = 0;
2417         struct inode *inode_alloc_inode;
2418         struct buffer_head *alloc_bh = NULL;
2419
2420         mlog_entry("blkno: %llu", (unsigned long long)blkno);
2421
2422         status = ocfs2_get_suballoc_slot_bit(osb, blkno, &suballoc_slot,
2423                                              &suballoc_bit);
2424         if (status < 0) {
2425                 mlog(ML_ERROR, "get alloc slot and bit failed %d\n", status);
2426                 goto bail;
2427         }
2428
2429         inode_alloc_inode =
2430                 ocfs2_get_system_file_inode(osb, INODE_ALLOC_SYSTEM_INODE,
2431                                             suballoc_slot);
2432         if (!inode_alloc_inode) {
2433                 /* the error code could be inaccurate, but we are not able to
2434                  * get the correct one. */
2435                 status = -EINVAL;
2436                 mlog(ML_ERROR, "unable to get alloc inode in slot %u\n",
2437                      (u32)suballoc_slot);
2438                 goto bail;
2439         }
2440
2441         mutex_lock(&inode_alloc_inode->i_mutex);
2442         status = ocfs2_inode_lock(inode_alloc_inode, &alloc_bh, 0);
2443         if (status < 0) {
2444                 mutex_unlock(&inode_alloc_inode->i_mutex);
2445                 mlog(ML_ERROR, "lock on alloc inode on slot %u failed %d\n",
2446                      (u32)suballoc_slot, status);
2447                 goto bail;
2448         }
2449
2450         status = ocfs2_test_suballoc_bit(osb, inode_alloc_inode, alloc_bh,
2451                                          blkno, suballoc_bit, res);
2452         if (status < 0)
2453                 mlog(ML_ERROR, "test suballoc bit failed %d\n", status);
2454
2455         ocfs2_inode_unlock(inode_alloc_inode, 0);
2456         mutex_unlock(&inode_alloc_inode->i_mutex);
2457
2458         iput(inode_alloc_inode);
2459         brelse(alloc_bh);
2460 bail:
2461         mlog_exit(status);
2462         return status;
2463 }