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   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 "dlmglue.h"
  39 #include "inode.h"
  40 #include "journal.h"
  41 #include "localalloc.h"
  42 #include "suballoc.h"
  43 #include "super.h"
  44 #include "sysfile.h"
  45 #include "uptodate.h"
  46
  47 #include "buffer_head_io.h"
  48
  49 #define NOT_ALLOC_NEW_GROUP             0
  50 #define ALLOC_NEW_GROUP                 1
  51
  52 #define OCFS2_MAX_INODES_TO_STEAL       1024
  53
  54 static inline void ocfs2_debug_bg(struct ocfs2_group_desc *bg);
  55 static inline void ocfs2_debug_suballoc_inode(struct ocfs2_dinode *fe);
  56 static inline u16 ocfs2_find_victim_chain(struct ocfs2_chain_list *cl);
  57 static int ocfs2_block_group_fill(handle_t *handle,
  58                                   struct inode *alloc_inode,
  59                                   struct buffer_head *bg_bh,
  60                                   u64 group_blkno,
  61                                   u16 my_chain,
  62                                   struct ocfs2_chain_list *cl);
  63 static int ocfs2_block_group_alloc(struct ocfs2_super *osb,
  64                                    struct inode *alloc_inode,
  65                                    struct buffer_head *bh,
  66                                    u64 max_block);
  67
  68 static int ocfs2_cluster_group_search(struct inode *inode,
  69                                       struct buffer_head *group_bh,
  70                                       u32 bits_wanted, u32 min_bits,
  71                                       u64 max_block,
  72                                       u16 *bit_off, u16 *bits_found);
  73 static int ocfs2_block_group_search(struct inode *inode,
  74                                     struct buffer_head *group_bh,
  75                                     u32 bits_wanted, u32 min_bits,
  76                                     u64 max_block,
  77                                     u16 *bit_off, u16 *bits_found);
  78 static int ocfs2_claim_suballoc_bits(struct ocfs2_super *osb,
  79                                      struct ocfs2_alloc_context *ac,
  80                                      handle_t *handle,
  81                                      u32 bits_wanted,
  82                                      u32 min_bits,
  83                                      u16 *bit_off,
  84                                      unsigned int *num_bits,
  85                                      u64 *bg_blkno);
  86 static int ocfs2_test_bg_bit_allocatable(struct buffer_head *bg_bh,
  87                                          int nr);
  88 static inline int ocfs2_block_group_set_bits(handle_t *handle,
  89                                              struct inode *alloc_inode,
  90                                              struct ocfs2_group_desc *bg,
  91                                              struct buffer_head *group_bh,
  92                                              unsigned int bit_off,
  93                                              unsigned int num_bits);
  94 static inline int ocfs2_block_group_clear_bits(handle_t *handle,
  95                                                struct inode *alloc_inode,
  96                                                struct ocfs2_group_desc *bg,
  97                                                struct buffer_head *group_bh,
  98                                                unsigned int bit_off,
  99                                                unsigned int num_bits);
 100
 101 static int ocfs2_relink_block_group(handle_t *handle,
 102                                     struct inode *alloc_inode,
 103                                     struct buffer_head *fe_bh,
 104                                     struct buffer_head *bg_bh,
 105                                     struct buffer_head *prev_bg_bh,
 106                                     u16 chain);
 107 static inline int ocfs2_block_group_reasonably_empty(struct ocfs2_group_desc *bg,
 108                                                      u32 wanted);
 109 static inline u32 ocfs2_desc_bitmap_to_cluster_off(struct inode *inode,
 110                                                    u64 bg_blkno,
 111                                                    u16 bg_bit_off);
 112 static inline void ocfs2_block_to_cluster_group(struct inode *inode,
 113                                                 u64 data_blkno,
 114                                                 u64 *bg_blkno,
 115                                                 u16 *bg_bit_off);
 116 static int ocfs2_reserve_clusters_with_limit(struct ocfs2_super *osb,
 117                                              u32 bits_wanted, u64 max_block,
 118                                              struct ocfs2_alloc_context **ac);
 119
 120 void ocfs2_free_ac_resource(struct ocfs2_alloc_context *ac)
 121 {
 122         struct inode *inode = ac->ac_inode;
 123
 124         if (inode) {
 125                 if (ac->ac_which != OCFS2_AC_USE_LOCAL)
 126                         ocfs2_inode_unlock(inode, 1);
 127
 128                 mutex_unlock(&inode->i_mutex);
 129
 130                 iput(inode);
 131                 ac->ac_inode = NULL;
 132         }
 133         brelse(ac->ac_bh);
 134         ac->ac_bh = NULL;
 135 }
 136
 137 void ocfs2_free_alloc_context(struct ocfs2_alloc_context *ac)
 138 {
 139         ocfs2_free_ac_resource(ac);
 140         kfree(ac);
 141 }
 142
 143 static u32 ocfs2_bits_per_group(struct ocfs2_chain_list *cl)
 144 {
 145         return (u32)le16_to_cpu(cl->cl_cpg) * (u32)le16_to_cpu(cl->cl_bpc);
 146 }
 147
 148 int ocfs2_validate_group_descriptor(struct super_block *sb,
 149                                     struct ocfs2_dinode *di,
 150                                     struct buffer_head *bh,
 151                                     int clean_error)
 152 {
 153         unsigned int max_bits;
 154         struct ocfs2_group_desc *gd = (struct ocfs2_group_desc *)bh->b_data;
 155
 156 #define do_error(fmt, ...)                                              \
 157         do{                                                             \
 158                 if (clean_error)                                        \
 159                         mlog(ML_ERROR, fmt "\n", ##__VA_ARGS__);        \
 160                 else                                                    \
 161                         ocfs2_error(sb, fmt, ##__VA_ARGS__);            \
 162         } while (0)
 163
 164         if (!OCFS2_IS_VALID_GROUP_DESC(gd)) {
 165                 do_error("Group descriptor #%llu has bad signature %.*s",
 166                          (unsigned long long)bh->b_blocknr, 7,
 167                          gd->bg_signature);
 168                 return -EINVAL;
 169         }
 170
 171         if (le64_to_cpu(gd->bg_blkno) != bh->b_blocknr) {
 172                 do_error("Group descriptor #%llu has an invalid bg_blkno "
 173                          "of %llu",
 174                          (unsigned long long)bh->b_blocknr,
 175                          (unsigned long long)le64_to_cpu(gd->bg_blkno));
 176                 return -EINVAL;
 177         }
 178
 179         if (le32_to_cpu(gd->bg_generation) != OCFS2_SB(sb)->fs_generation) {
 180                 do_error("Group descriptor #%llu has an invalid "
 181                          "fs_generation of #%u",
 182                          (unsigned long long)bh->b_blocknr,
 183                          le32_to_cpu(gd->bg_generation));
 184                 return -EINVAL;
 185         }
 186
 187         if (di->i_blkno != gd->bg_parent_dinode) {
 188                 do_error("Group descriptor #%llu has bad parent "
 189                          "pointer (%llu, expected %llu)",
 190                          (unsigned long long)bh->b_blocknr,
 191                          (unsigned long long)le64_to_cpu(gd->bg_parent_dinode),
 192                          (unsigned long long)le64_to_cpu(di->i_blkno));
 193                 return -EINVAL;
 194         }
 195
 196         max_bits = le16_to_cpu(di->id2.i_chain.cl_cpg) * le16_to_cpu(di->id2.i_chain.cl_bpc);
 197         if (le16_to_cpu(gd->bg_bits) > max_bits) {
 198                 do_error("Group descriptor #%llu has bit count of %u",
 199                          (unsigned long long)bh->b_blocknr,
 200                          le16_to_cpu(gd->bg_bits));
 201                 return -EINVAL;
 202         }
 203
 204         if (le16_to_cpu(gd->bg_chain) >=
 205             le16_to_cpu(di->id2.i_chain.cl_next_free_rec)) {
 206                 do_error("Group descriptor #%llu has bad chain %u",
 207                          (unsigned long long)bh->b_blocknr,
 208                          le16_to_cpu(gd->bg_chain));
 209                 return -EINVAL;
 210         }
 211
 212         if (le16_to_cpu(gd->bg_free_bits_count) > le16_to_cpu(gd->bg_bits)) {
 213                 do_error("Group descriptor #%llu has bit count %u but "
 214                          "claims that %u are free",
 215                          (unsigned long long)bh->b_blocknr,
 216                          le16_to_cpu(gd->bg_bits),
 217                          le16_to_cpu(gd->bg_free_bits_count));
 218                 return -EINVAL;
 219         }
 220
 221         if (le16_to_cpu(gd->bg_bits) > (8 * le16_to_cpu(gd->bg_size))) {
 222                 do_error("Group descriptor #%llu has bit count %u but "
 223                          "max bitmap bits of %u",
 224                          (unsigned long long)bh->b_blocknr,
 225                          le16_to_cpu(gd->bg_bits),
 226                          8 * le16_to_cpu(gd->bg_size));
 227                 return -EINVAL;
 228         }
 229 #undef do_error
 230
 231         return 0;
 232 }
 233
 234 int ocfs2_read_group_descriptor(struct inode *inode, struct ocfs2_dinode *di,
 235                                 u64 gd_blkno, struct buffer_head **bh)
 236 {
 237         int rc;
 238         struct buffer_head *tmp = *bh;
 239
 240         rc = ocfs2_read_block(inode, gd_blkno, &tmp);
 241         if (rc)
 242                 goto out;
 243
 244         rc = ocfs2_validate_group_descriptor(inode->i_sb, di, tmp, 0);
 245         if (rc) {
 246                 brelse(tmp);
 247                 goto out;
 248         }
 249
 250         /* If ocfs2_read_block() got us a new bh, pass it up. */
 251         if (!*bh)
 252                 *bh = tmp;
 253
 254 out:
 255         return rc;
 256 }
 257
 258 static int ocfs2_block_group_fill(handle_t *handle,
 259                                   struct inode *alloc_inode,
 260                                   struct buffer_head *bg_bh,
 261                                   u64 group_blkno,
 262                                   u16 my_chain,
 263                                   struct ocfs2_chain_list *cl)
 264 {
 265         int status = 0;
 266         struct ocfs2_group_desc *bg = (struct ocfs2_group_desc *) bg_bh->b_data;
 267         struct super_block * sb = alloc_inode->i_sb;
 268
 269         mlog_entry_void();
 270
 271         if (((unsigned long long) bg_bh->b_blocknr) != group_blkno) {
 272                 ocfs2_error(alloc_inode->i_sb, "group block (%llu) != "
 273                             "b_blocknr (%llu)",
 274                             (unsigned long long)group_blkno,
 275                             (unsigned long long) bg_bh->b_blocknr);
 276                 status = -EIO;
 277                 goto bail;
 278         }
 279
 280         status = ocfs2_journal_access(handle,
 281                                       alloc_inode,
 282                                       bg_bh,
 283                                       OCFS2_JOURNAL_ACCESS_CREATE);
 284         if (status < 0) {
 285                 mlog_errno(status);
 286                 goto bail;
 287         }
 288
 289         memset(bg, 0, sb->s_blocksize);
 290         strcpy(bg->bg_signature, OCFS2_GROUP_DESC_SIGNATURE);
 291         bg->bg_generation = cpu_to_le32(OCFS2_SB(sb)->fs_generation);
 292         bg->bg_size = cpu_to_le16(ocfs2_group_bitmap_size(sb));
 293         bg->bg_bits = cpu_to_le16(ocfs2_bits_per_group(cl));
 294         bg->bg_chain = cpu_to_le16(my_chain);
 295         bg->bg_next_group = cl->cl_recs[my_chain].c_blkno;
 296         bg->bg_parent_dinode = cpu_to_le64(OCFS2_I(alloc_inode)->ip_blkno);
 297         bg->bg_blkno = cpu_to_le64(group_blkno);
 298         /* set the 1st bit in the bitmap to account for the descriptor block */
 299         ocfs2_set_bit(0, (unsigned long *)bg->bg_bitmap);
 300         bg->bg_free_bits_count = cpu_to_le16(le16_to_cpu(bg->bg_bits) - 1);
 301
 302         status = ocfs2_journal_dirty(handle, bg_bh);
 303         if (status < 0)
 304                 mlog_errno(status);
 305
 306         /* There is no need to zero out or otherwise initialize the
 307          * other blocks in a group - All valid FS metadata in a block
 308          * group stores the superblock fs_generation value at
 309          * allocation time. */
 310
 311 bail:
 312         mlog_exit(status);
 313         return status;
 314 }
 315
 316 static inline u16 ocfs2_find_smallest_chain(struct ocfs2_chain_list *cl)
 317 {
 318         u16 curr, best;
 319
 320         best = curr = 0;
 321         while (curr < le16_to_cpu(cl->cl_count)) {
 322                 if (le32_to_cpu(cl->cl_recs[best].c_total) >
 323                     le32_to_cpu(cl->cl_recs[curr].c_total))
 324                         best = curr;
 325                 curr++;
 326         }
 327         return best;
 328 }
 329
 330 /*
 331  * We expect the block group allocator to already be locked.
 332  */
 333 static int ocfs2_block_group_alloc(struct ocfs2_super *osb,
 334                                    struct inode *alloc_inode,
 335                                    struct buffer_head *bh,
 336                                    u64 max_block)
 337 {
 338         int status, credits;
 339         struct ocfs2_dinode *fe = (struct ocfs2_dinode *) bh->b_data;
 340         struct ocfs2_chain_list *cl;
 341         struct ocfs2_alloc_context *ac = NULL;
 342         handle_t *handle = NULL;
 343         u32 bit_off, num_bits;
 344         u16 alloc_rec;
 345         u64 bg_blkno;
 346         struct buffer_head *bg_bh = NULL;
 347         struct ocfs2_group_desc *bg;
 348
 349         BUG_ON(ocfs2_is_cluster_bitmap(alloc_inode));
 350
 351         mlog_entry_void();
 352
 353         cl = &fe->id2.i_chain;
 354         status = ocfs2_reserve_clusters_with_limit(osb,
 355                                                    le16_to_cpu(cl->cl_cpg),
 356                                                    max_block, &ac);
 357         if (status < 0) {
 358                 if (status != -ENOSPC)
 359                         mlog_errno(status);
 360                 goto bail;
 361         }
 362
 363         credits = ocfs2_calc_group_alloc_credits(osb->sb,
 364                                                  le16_to_cpu(cl->cl_cpg));
 365         handle = ocfs2_start_trans(osb, credits);
 366         if (IS_ERR(handle)) {
 367                 status = PTR_ERR(handle);
 368                 handle = NULL;
 369                 mlog_errno(status);
 370                 goto bail;
 371         }
 372
 373         status = ocfs2_claim_clusters(osb,
 374                                       handle,
 375                                       ac,
 376                                       le16_to_cpu(cl->cl_cpg),
 377                                       &bit_off,
 378                                       &num_bits);
 379         if (status < 0) {
 380                 if (status != -ENOSPC)
 381                         mlog_errno(status);
 382                 goto bail;
 383         }
 384
 385         alloc_rec = ocfs2_find_smallest_chain(cl);
 386
 387         /* setup the group */
 388         bg_blkno = ocfs2_clusters_to_blocks(osb->sb, bit_off);
 389         mlog(0, "new descriptor, record %u, at block %llu\n",
 390              alloc_rec, (unsigned long long)bg_blkno);
 391
 392         bg_bh = sb_getblk(osb->sb, bg_blkno);
 393         if (!bg_bh) {
 394                 status = -EIO;
 395                 mlog_errno(status);
 396                 goto bail;
 397         }
 398         ocfs2_set_new_buffer_uptodate(alloc_inode, bg_bh);
 399
 400         status = ocfs2_block_group_fill(handle,
 401                                         alloc_inode,
 402                                         bg_bh,
 403                                         bg_blkno,
 404                                         alloc_rec,
 405                                         cl);
 406         if (status < 0) {
 407                 mlog_errno(status);
 408                 goto bail;
 409         }
 410
 411         bg = (struct ocfs2_group_desc *) bg_bh->b_data;
 412
 413         status = ocfs2_journal_access(handle, alloc_inode,
 414                                       bh, OCFS2_JOURNAL_ACCESS_WRITE);
 415         if (status < 0) {
 416                 mlog_errno(status);
 417                 goto bail;
 418         }
 419
 420         le32_add_cpu(&cl->cl_recs[alloc_rec].c_free,
 421                      le16_to_cpu(bg->bg_free_bits_count));
 422         le32_add_cpu(&cl->cl_recs[alloc_rec].c_total, le16_to_cpu(bg->bg_bits));
 423         cl->cl_recs[alloc_rec].c_blkno  = cpu_to_le64(bg_blkno);
 424         if (le16_to_cpu(cl->cl_next_free_rec) < le16_to_cpu(cl->cl_count))
 425                 le16_add_cpu(&cl->cl_next_free_rec, 1);
 426
 427         le32_add_cpu(&fe->id1.bitmap1.i_used, le16_to_cpu(bg->bg_bits) -
 428                                         le16_to_cpu(bg->bg_free_bits_count));
 429         le32_add_cpu(&fe->id1.bitmap1.i_total, le16_to_cpu(bg->bg_bits));
 430         le32_add_cpu(&fe->i_clusters, le16_to_cpu(cl->cl_cpg));
 431
 432         status = ocfs2_journal_dirty(handle, bh);
 433         if (status < 0) {
 434                 mlog_errno(status);
 435                 goto bail;
 436         }
 437
 438         spin_lock(&OCFS2_I(alloc_inode)->ip_lock);
 439         OCFS2_I(alloc_inode)->ip_clusters = le32_to_cpu(fe->i_clusters);
 440         fe->i_size = cpu_to_le64(ocfs2_clusters_to_bytes(alloc_inode->i_sb,
 441                                              le32_to_cpu(fe->i_clusters)));
 442         spin_unlock(&OCFS2_I(alloc_inode)->ip_lock);
 443         i_size_write(alloc_inode, le64_to_cpu(fe->i_size));
 444         alloc_inode->i_blocks = ocfs2_inode_sector_count(alloc_inode);
 445
 446         status = 0;
 447 bail:
 448         if (handle)
 449                 ocfs2_commit_trans(osb, handle);
 450
 451         if (ac)
 452                 ocfs2_free_alloc_context(ac);
 453
 454         brelse(bg_bh);
 455
 456         mlog_exit(status);
 457         return status;
 458 }
 459
 460 static int ocfs2_reserve_suballoc_bits(struct ocfs2_super *osb,
 461                                        struct ocfs2_alloc_context *ac,
 462                                        int type,
 463                                        u32 slot,
 464                                        int alloc_new_group)
 465 {
 466         int status;
 467         u32 bits_wanted = ac->ac_bits_wanted;
 468         struct inode *alloc_inode;
 469         struct buffer_head *bh = NULL;
 470         struct ocfs2_dinode *fe;
 471         u32 free_bits;
 472
 473         mlog_entry_void();
 474
 475         alloc_inode = ocfs2_get_system_file_inode(osb, type, slot);
 476         if (!alloc_inode) {
 477                 mlog_errno(-EINVAL);
 478                 return -EINVAL;
 479         }
 480
 481         mutex_lock(&alloc_inode->i_mutex);
 482
 483         status = ocfs2_inode_lock(alloc_inode, &bh, 1);
 484         if (status < 0) {
 485                 mutex_unlock(&alloc_inode->i_mutex);
 486                 iput(alloc_inode);
 487
 488                 mlog_errno(status);
 489                 return status;
 490         }
 491
 492         ac->ac_inode = alloc_inode;
 493         ac->ac_alloc_slot = slot;
 494
 495         fe = (struct ocfs2_dinode *) bh->b_data;
 496
 497         /* The bh was validated by the inode read inside
 498          * ocfs2_inode_lock().  Any corruption is a code bug. */
 499         BUG_ON(!OCFS2_IS_VALID_DINODE(fe));
 500
 501         if (!(fe->i_flags & cpu_to_le32(OCFS2_CHAIN_FL))) {
 502                 ocfs2_error(alloc_inode->i_sb, "Invalid chain allocator %llu",
 503                             (unsigned long long)le64_to_cpu(fe->i_blkno));
 504                 status = -EIO;
 505                 goto bail;
 506         }
 507
 508         free_bits = le32_to_cpu(fe->id1.bitmap1.i_total) -
 509                 le32_to_cpu(fe->id1.bitmap1.i_used);
 510
 511         if (bits_wanted > free_bits) {
 512                 /* cluster bitmap never grows */
 513                 if (ocfs2_is_cluster_bitmap(alloc_inode)) {
 514                         mlog(0, "Disk Full: wanted=%u, free_bits=%u\n",
 515                              bits_wanted, free_bits);
 516                         status = -ENOSPC;
 517                         goto bail;
 518                 }
 519
 520                 if (alloc_new_group != ALLOC_NEW_GROUP) {
 521                         mlog(0, "Alloc File %u Full: wanted=%u, free_bits=%u, "
 522                              "and we don't alloc a new group for it.\n",
 523                              slot, bits_wanted, free_bits);
 524                         status = -ENOSPC;
 525                         goto bail;
 526                 }
 527
 528                 status = ocfs2_block_group_alloc(osb, alloc_inode, bh,
 529                                                  ac->ac_max_block);
 530                 if (status < 0) {
 531                         if (status != -ENOSPC)
 532                                 mlog_errno(status);
 533                         goto bail;
 534                 }
 535                 atomic_inc(&osb->alloc_stats.bg_extends);
 536
 537                 /* You should never ask for this much metadata */
 538                 BUG_ON(bits_wanted >
 539                        (le32_to_cpu(fe->id1.bitmap1.i_total)
 540                         - le32_to_cpu(fe->id1.bitmap1.i_used)));
 541         }
 542
 543         get_bh(bh);
 544         ac->ac_bh = bh;
 545 bail:
 546         brelse(bh);
 547
 548         mlog_exit(status);
 549         return status;
 550 }
 551
 552 int ocfs2_reserve_new_metadata_blocks(struct ocfs2_super *osb,
 553                                       int blocks,
 554                                       struct ocfs2_alloc_context **ac)
 555 {
 556         int status;
 557         u32 slot;
 558
 559         *ac = kzalloc(sizeof(struct ocfs2_alloc_context), GFP_KERNEL);
 560         if (!(*ac)) {
 561                 status = -ENOMEM;
 562                 mlog_errno(status);
 563                 goto bail;
 564         }
 565
 566         (*ac)->ac_bits_wanted = blocks;
 567         (*ac)->ac_which = OCFS2_AC_USE_META;
 568         slot = osb->slot_num;
 569         (*ac)->ac_group_search = ocfs2_block_group_search;
 570
 571         status = ocfs2_reserve_suballoc_bits(osb, (*ac),
 572                                              EXTENT_ALLOC_SYSTEM_INODE,
 573                                              slot, ALLOC_NEW_GROUP);
 574         if (status < 0) {
 575                 if (status != -ENOSPC)
 576                         mlog_errno(status);
 577                 goto bail;
 578         }
 579
 580         status = 0;
 581 bail:
 582         if ((status < 0) && *ac) {
 583                 ocfs2_free_alloc_context(*ac);
 584                 *ac = NULL;
 585         }
 586
 587         mlog_exit(status);
 588         return status;
 589 }
 590
 591 int ocfs2_reserve_new_metadata(struct ocfs2_super *osb,
 592                                struct ocfs2_extent_list *root_el,
 593                                struct ocfs2_alloc_context **ac)
 594 {
 595         return ocfs2_reserve_new_metadata_blocks(osb,
 596                                         ocfs2_extend_meta_needed(root_el),
 597                                         ac);
 598 }
 599
 600 static int ocfs2_steal_inode_from_other_nodes(struct ocfs2_super *osb,
 601                                               struct ocfs2_alloc_context *ac)
 602 {
 603         int i, status = -ENOSPC;
 604         s16 slot = ocfs2_get_inode_steal_slot(osb);
 605
 606         /* Start to steal inodes from the first slot after ours. */
 607         if (slot == OCFS2_INVALID_SLOT)
 608                 slot = osb->slot_num + 1;
 609
 610         for (i = 0; i < osb->max_slots; i++, slot++) {
 611                 if (slot == osb->max_slots)
 612                         slot = 0;
 613
 614                 if (slot == osb->slot_num)
 615                         continue;
 616
 617                 status = ocfs2_reserve_suballoc_bits(osb, ac,
 618                                                      INODE_ALLOC_SYSTEM_INODE,
 619                                                      slot, NOT_ALLOC_NEW_GROUP);
 620                 if (status >= 0) {
 621                         ocfs2_set_inode_steal_slot(osb, slot);
 622                         break;
 623                 }
 624
 625                 ocfs2_free_ac_resource(ac);
 626         }
 627
 628         return status;
 629 }
 630
 631 int ocfs2_reserve_new_inode(struct ocfs2_super *osb,
 632                             struct ocfs2_alloc_context **ac)
 633 {
 634         int status;
 635         s16 slot = ocfs2_get_inode_steal_slot(osb);
 636
 637         *ac = kzalloc(sizeof(struct ocfs2_alloc_context), GFP_KERNEL);
 638         if (!(*ac)) {
 639                 status = -ENOMEM;
 640                 mlog_errno(status);
 641                 goto bail;
 642         }
 643
 644         (*ac)->ac_bits_wanted = 1;
 645         (*ac)->ac_which = OCFS2_AC_USE_INODE;
 646
 647         (*ac)->ac_group_search = ocfs2_block_group_search;
 648
 649         /*
 650          * stat(2) can't handle i_ino > 32bits, so we tell the
 651          * lower levels not to allocate us a block group past that
 652          * limit.  The 'inode64' mount option avoids this behavior.
 653          */
 654         if (!(osb->s_mount_opt & OCFS2_MOUNT_INODE64))
 655                 (*ac)->ac_max_block = (u32)~0U;
 656
 657         /*
 658          * slot is set when we successfully steal inode from other nodes.
 659          * It is reset in 3 places:
 660          * 1. when we flush the truncate log
 661          * 2. when we complete local alloc recovery.
 662          * 3. when we successfully allocate from our own slot.
 663          * After it is set, we will go on stealing inodes until we find the
 664          * need to check our slots to see whether there is some space for us.
 665          */
 666         if (slot != OCFS2_INVALID_SLOT &&
 667             atomic_read(&osb->s_num_inodes_stolen) < OCFS2_MAX_INODES_TO_STEAL)
 668                 goto inode_steal;
 669
 670         atomic_set(&osb->s_num_inodes_stolen, 0);
 671         status = ocfs2_reserve_suballoc_bits(osb, *ac,
 672                                              INODE_ALLOC_SYSTEM_INODE,
 673                                              osb->slot_num, ALLOC_NEW_GROUP);
 674         if (status >= 0) {
 675                 status = 0;
 676
 677                 /*
 678                  * Some inodes must be freed by us, so try to allocate
 679                  * from our own next time.
 680                  */
 681                 if (slot != OCFS2_INVALID_SLOT)
 682                         ocfs2_init_inode_steal_slot(osb);
 683                 goto bail;
 684         } else if (status < 0 && status != -ENOSPC) {
 685                 mlog_errno(status);
 686                 goto bail;
 687         }
 688
 689         ocfs2_free_ac_resource(*ac);
 690
 691 inode_steal:
 692         status = ocfs2_steal_inode_from_other_nodes(osb, *ac);
 693         atomic_inc(&osb->s_num_inodes_stolen);
 694         if (status < 0) {
 695                 if (status != -ENOSPC)
 696                         mlog_errno(status);
 697                 goto bail;
 698         }
 699
 700         status = 0;
 701 bail:
 702         if ((status < 0) && *ac) {
 703                 ocfs2_free_alloc_context(*ac);
 704                 *ac = NULL;
 705         }
 706
 707         mlog_exit(status);
 708         return status;
 709 }
 710
 711 /* local alloc code has to do the same thing, so rather than do this
 712  * twice.. */
 713 int ocfs2_reserve_cluster_bitmap_bits(struct ocfs2_super *osb,
 714                                       struct ocfs2_alloc_context *ac)
 715 {
 716         int status;
 717
 718         ac->ac_which = OCFS2_AC_USE_MAIN;
 719         ac->ac_group_search = ocfs2_cluster_group_search;
 720
 721         status = ocfs2_reserve_suballoc_bits(osb, ac,
 722                                              GLOBAL_BITMAP_SYSTEM_INODE,
 723                                              OCFS2_INVALID_SLOT,
 724                                              ALLOC_NEW_GROUP);
 725         if (status < 0 && status != -ENOSPC) {
 726                 mlog_errno(status);
 727                 goto bail;
 728         }
 729
 730 bail:
 731         return status;
 732 }
 733
 734 /* Callers don't need to care which bitmap (local alloc or main) to
 735  * use so we figure it out for them, but unfortunately this clutters
 736  * things a bit. */
 737 static int ocfs2_reserve_clusters_with_limit(struct ocfs2_super *osb,
 738                                              u32 bits_wanted, u64 max_block,
 739                                              struct ocfs2_alloc_context **ac)
 740 {
 741         int status;
 742
 743         mlog_entry_void();
 744
 745         *ac = kzalloc(sizeof(struct ocfs2_alloc_context), GFP_KERNEL);
 746         if (!(*ac)) {
 747                 status = -ENOMEM;
 748                 mlog_errno(status);
 749                 goto bail;
 750         }
 751
 752         (*ac)->ac_bits_wanted = bits_wanted;
 753         (*ac)->ac_max_block = max_block;
 754
 755         status = -ENOSPC;
 756         if (ocfs2_alloc_should_use_local(osb, bits_wanted)) {
 757                 status = ocfs2_reserve_local_alloc_bits(osb,
 758                                                         bits_wanted,
 759                                                         *ac);
 760                 if (status == -EFBIG) {
 761                         /* The local alloc window is outside ac_max_block.
 762                          * use the main bitmap. */
 763                         status = -ENOSPC;
 764                 } else if ((status < 0) && (status != -ENOSPC)) {
 765                         mlog_errno(status);
 766                         goto bail;
 767                 }
 768         }
 769
 770         if (status == -ENOSPC) {
 771                 status = ocfs2_reserve_cluster_bitmap_bits(osb, *ac);
 772                 if (status < 0) {
 773                         if (status != -ENOSPC)
 774                                 mlog_errno(status);
 775                         goto bail;
 776                 }
 777         }
 778
 779         status = 0;
 780 bail:
 781         if ((status < 0) && *ac) {
 782                 ocfs2_free_alloc_context(*ac);
 783                 *ac = NULL;
 784         }
 785
 786         mlog_exit(status);
 787         return status;
 788 }
 789
 790 int ocfs2_reserve_clusters(struct ocfs2_super *osb,
 791                            u32 bits_wanted,
 792                            struct ocfs2_alloc_context **ac)
 793 {
 794         return ocfs2_reserve_clusters_with_limit(osb, bits_wanted, 0, ac);
 795 }
 796
 797 /*
 798  * More or less lifted from ext3. I'll leave their description below:
 799  *
 800  * "For ext3 allocations, we must not reuse any blocks which are
 801  * allocated in the bitmap buffer's "last committed data" copy.  This
 802  * prevents deletes from freeing up the page for reuse until we have
 803  * committed the delete transaction.
 804  *
 805  * If we didn't do this, then deleting something and reallocating it as
 806  * data would allow the old block to be overwritten before the
 807  * transaction committed (because we force data to disk before commit).
 808  * This would lead to corruption if we crashed between overwriting the
 809  * data and committing the delete.
 810  *
 811  * @@@ We may want to make this allocation behaviour conditional on
 812  * data-writes at some point, and disable it for metadata allocations or
 813  * sync-data inodes."
 814  *
 815  * Note: OCFS2 already does this differently for metadata vs data
 816  * allocations, as those bitmaps are separate and undo access is never
 817  * called on a metadata group descriptor.
 818  */
 819 static int ocfs2_test_bg_bit_allocatable(struct buffer_head *bg_bh,
 820                                          int nr)
 821 {
 822         struct ocfs2_group_desc *bg = (struct ocfs2_group_desc *) bg_bh->b_data;
 823
 824         if (ocfs2_test_bit(nr, (unsigned long *)bg->bg_bitmap))
 825                 return 0;
 826         if (!buffer_jbd(bg_bh) || !bh2jh(bg_bh)->b_committed_data)
 827                 return 1;
 828
 829         bg = (struct ocfs2_group_desc *) bh2jh(bg_bh)->b_committed_data;
 830         return !ocfs2_test_bit(nr, (unsigned long *)bg->bg_bitmap);
 831 }
 832
 833 static int ocfs2_block_group_find_clear_bits(struct ocfs2_super *osb,
 834                                              struct buffer_head *bg_bh,
 835                                              unsigned int bits_wanted,
 836                                              unsigned int total_bits,
 837                                              u16 *bit_off,
 838                                              u16 *bits_found)
 839 {
 840         void *bitmap;
 841         u16 best_offset, best_size;
 842         int offset, start, found, status = 0;
 843         struct ocfs2_group_desc *bg = (struct ocfs2_group_desc *) bg_bh->b_data;
 844
 845         if (!OCFS2_IS_VALID_GROUP_DESC(bg)) {
 846                 OCFS2_RO_ON_INVALID_GROUP_DESC(osb->sb, bg);
 847                 return -EIO;
 848         }
 849
 850         found = start = best_offset = best_size = 0;
 851         bitmap = bg->bg_bitmap;
 852
 853         while((offset = ocfs2_find_next_zero_bit(bitmap, total_bits, start)) != -1) {
 854                 if (offset == total_bits)
 855                         break;
 856
 857                 if (!ocfs2_test_bg_bit_allocatable(bg_bh, offset)) {
 858                         /* We found a zero, but we can't use it as it
 859                          * hasn't been put to disk yet! */
 860                         found = 0;
 861                         start = offset + 1;
 862                 } else if (offset == start) {
 863                         /* we found a zero */
 864                         found++;
 865                         /* move start to the next bit to test */
 866                         start++;
 867                 } else {
 868                         /* got a zero after some ones */
 869                         found = 1;
 870                         start = offset + 1;
 871                 }
 872                 if (found > best_size) {
 873                         best_size = found;
 874                         best_offset = start - found;
 875                 }
 876                 /* we got everything we needed */
 877                 if (found == bits_wanted) {
 878                         /* mlog(0, "Found it all!\n"); */
 879                         break;
 880                 }
 881         }
 882
 883         /* XXX: I think the first clause is equivalent to the second
 884          *      - jlbec */
 885         if (found == bits_wanted) {
 886                 *bit_off = start - found;
 887                 *bits_found = found;
 888         } else if (best_size) {
 889                 *bit_off = best_offset;
 890                 *bits_found = best_size;
 891         } else {
 892                 status = -ENOSPC;
 893                 /* No error log here -- see the comment above
 894                  * ocfs2_test_bg_bit_allocatable */
 895         }
 896
 897         return status;
 898 }
 899
 900 static inline int ocfs2_block_group_set_bits(handle_t *handle,
 901                                              struct inode *alloc_inode,
 902                                              struct ocfs2_group_desc *bg,
 903                                              struct buffer_head *group_bh,
 904                                              unsigned int bit_off,
 905                                              unsigned int num_bits)
 906 {
 907         int status;
 908         void *bitmap = bg->bg_bitmap;
 909         int journal_type = OCFS2_JOURNAL_ACCESS_WRITE;
 910
 911         mlog_entry_void();
 912
 913         if (!OCFS2_IS_VALID_GROUP_DESC(bg)) {
 914                 OCFS2_RO_ON_INVALID_GROUP_DESC(alloc_inode->i_sb, bg);
 915                 status = -EIO;
 916                 goto bail;
 917         }
 918         BUG_ON(le16_to_cpu(bg->bg_free_bits_count) < num_bits);
 919
 920         mlog(0, "block_group_set_bits: off = %u, num = %u\n", bit_off,
 921              num_bits);
 922
 923         if (ocfs2_is_cluster_bitmap(alloc_inode))
 924                 journal_type = OCFS2_JOURNAL_ACCESS_UNDO;
 925
 926         status = ocfs2_journal_access(handle,
 927                                       alloc_inode,
 928                                       group_bh,
 929                                       journal_type);
 930         if (status < 0) {
 931                 mlog_errno(status);
 932                 goto bail;
 933         }
 934
 935         le16_add_cpu(&bg->bg_free_bits_count, -num_bits);
 936
 937         while(num_bits--)
 938                 ocfs2_set_bit(bit_off++, bitmap);
 939
 940         status = ocfs2_journal_dirty(handle,
 941                                      group_bh);
 942         if (status < 0) {
 943                 mlog_errno(status);
 944                 goto bail;
 945         }
 946
 947 bail:
 948         mlog_exit(status);
 949         return status;
 950 }
 951
 952 /* find the one with the most empty bits */
 953 static inline u16 ocfs2_find_victim_chain(struct ocfs2_chain_list *cl)
 954 {
 955         u16 curr, best;
 956
 957         BUG_ON(!cl->cl_next_free_rec);
 958
 959         best = curr = 0;
 960         while (curr < le16_to_cpu(cl->cl_next_free_rec)) {
 961                 if (le32_to_cpu(cl->cl_recs[curr].c_free) >
 962                     le32_to_cpu(cl->cl_recs[best].c_free))
 963                         best = curr;
 964                 curr++;
 965         }
 966
 967         BUG_ON(best >= le16_to_cpu(cl->cl_next_free_rec));
 968         return best;
 969 }
 970
 971 static int ocfs2_relink_block_group(handle_t *handle,
 972                                     struct inode *alloc_inode,
 973                                     struct buffer_head *fe_bh,
 974                                     struct buffer_head *bg_bh,
 975                                     struct buffer_head *prev_bg_bh,
 976                                     u16 chain)
 977 {
 978         int status;
 979         /* there is a really tiny chance the journal calls could fail,
 980          * but we wouldn't want inconsistent blocks in *any* case. */
 981         u64 fe_ptr, bg_ptr, prev_bg_ptr;
 982         struct ocfs2_dinode *fe = (struct ocfs2_dinode *) fe_bh->b_data;
 983         struct ocfs2_group_desc *bg = (struct ocfs2_group_desc *) bg_bh->b_data;
 984         struct ocfs2_group_desc *prev_bg = (struct ocfs2_group_desc *) prev_bg_bh->b_data;
 985
 986         if (!OCFS2_IS_VALID_GROUP_DESC(bg)) {
 987                 OCFS2_RO_ON_INVALID_GROUP_DESC(alloc_inode->i_sb, bg);
 988                 status = -EIO;
 989                 goto out;
 990         }
 991         if (!OCFS2_IS_VALID_GROUP_DESC(prev_bg)) {
 992                 OCFS2_RO_ON_INVALID_GROUP_DESC(alloc_inode->i_sb, prev_bg);
 993                 status = -EIO;
 994                 goto out;
 995         }
 996
 997         mlog(0, "Suballoc %llu, chain %u, move group %llu to top, prev = %llu\n",
 998              (unsigned long long)le64_to_cpu(fe->i_blkno), chain,
 999              (unsigned long long)le64_to_cpu(bg->bg_blkno),
1000              (unsigned long long)le64_to_cpu(prev_bg->bg_blkno));
1001
1002         fe_ptr = le64_to_cpu(fe->id2.i_chain.cl_recs[chain].c_blkno);
1003         bg_ptr = le64_to_cpu(bg->bg_next_group);
1004         prev_bg_ptr = le64_to_cpu(prev_bg->bg_next_group);
1005
1006         status = ocfs2_journal_access(handle, alloc_inode, prev_bg_bh,
1007                                       OCFS2_JOURNAL_ACCESS_WRITE);
1008         if (status < 0) {
1009                 mlog_errno(status);
1010                 goto out_rollback;
1011         }
1012
1013         prev_bg->bg_next_group = bg->bg_next_group;
1014
1015         status = ocfs2_journal_dirty(handle, prev_bg_bh);
1016         if (status < 0) {
1017                 mlog_errno(status);
1018                 goto out_rollback;
1019         }
1020
1021         status = ocfs2_journal_access(handle, alloc_inode, bg_bh,
1022                                       OCFS2_JOURNAL_ACCESS_WRITE);
1023         if (status < 0) {
1024                 mlog_errno(status);
1025                 goto out_rollback;
1026         }
1027
1028         bg->bg_next_group = fe->id2.i_chain.cl_recs[chain].c_blkno;
1029
1030         status = ocfs2_journal_dirty(handle, bg_bh);
1031         if (status < 0) {
1032                 mlog_errno(status);
1033                 goto out_rollback;
1034         }
1035
1036         status = ocfs2_journal_access(handle, alloc_inode, fe_bh,
1037                                       OCFS2_JOURNAL_ACCESS_WRITE);
1038         if (status < 0) {
1039                 mlog_errno(status);
1040                 goto out_rollback;
1041         }
1042
1043         fe->id2.i_chain.cl_recs[chain].c_blkno = bg->bg_blkno;
1044
1045         status = ocfs2_journal_dirty(handle, fe_bh);
1046         if (status < 0) {
1047                 mlog_errno(status);
1048                 goto out_rollback;
1049         }
1050
1051         status = 0;
1052 out_rollback:
1053         if (status < 0) {
1054                 fe->id2.i_chain.cl_recs[chain].c_blkno = cpu_to_le64(fe_ptr);
1055                 bg->bg_next_group = cpu_to_le64(bg_ptr);
1056                 prev_bg->bg_next_group = cpu_to_le64(prev_bg_ptr);
1057         }
1058 out:
1059         mlog_exit(status);
1060         return status;
1061 }
1062
1063 static inline int ocfs2_block_group_reasonably_empty(struct ocfs2_group_desc *bg,
1064                                                      u32 wanted)
1065 {
1066         return le16_to_cpu(bg->bg_free_bits_count) > wanted;
1067 }
1068
1069 /* return 0 on success, -ENOSPC to keep searching and any other < 0
1070  * value on error. */
1071 static int ocfs2_cluster_group_search(struct inode *inode,
1072                                       struct buffer_head *group_bh,
1073                                       u32 bits_wanted, u32 min_bits,
1074                                       u64 max_block,
1075                                       u16 *bit_off, u16 *bits_found)
1076 {
1077         int search = -ENOSPC;
1078         int ret;
1079         u64 blkoff;
1080         struct ocfs2_group_desc *gd = (struct ocfs2_group_desc *) group_bh->b_data;
1081         struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
1082         u16 tmp_off, tmp_found;
1083         unsigned int max_bits, gd_cluster_off;
1084
1085         BUG_ON(!ocfs2_is_cluster_bitmap(inode));
1086
1087         if (gd->bg_free_bits_count) {
1088                 max_bits = le16_to_cpu(gd->bg_bits);
1089
1090                 /* Tail groups in cluster bitmaps which aren't cpg
1091                  * aligned are prone to partial extention by a failed
1092                  * fs resize. If the file system resize never got to
1093                  * update the dinode cluster count, then we don't want
1094                  * to trust any clusters past it, regardless of what
1095                  * the group descriptor says. */
1096                 gd_cluster_off = ocfs2_blocks_to_clusters(inode->i_sb,
1097                                                           le64_to_cpu(gd->bg_blkno));
1098                 if ((gd_cluster_off + max_bits) >
1099                     OCFS2_I(inode)->ip_clusters) {
1100                         max_bits = OCFS2_I(inode)->ip_clusters - gd_cluster_off;
1101                         mlog(0, "Desc %llu, bg_bits %u, clusters %u, use %u\n",
1102                              (unsigned long long)le64_to_cpu(gd->bg_blkno),
1103                              le16_to_cpu(gd->bg_bits),
1104                              OCFS2_I(inode)->ip_clusters, max_bits);
1105                 }
1106
1107                 ret = ocfs2_block_group_find_clear_bits(OCFS2_SB(inode->i_sb),
1108                                                         group_bh, bits_wanted,
1109                                                         max_bits,
1110                                                         &tmp_off, &tmp_found);
1111                 if (ret)
1112                         return ret;
1113
1114                 if (max_block) {
1115                         blkoff = ocfs2_clusters_to_blocks(inode->i_sb,
1116                                                           gd_cluster_off +
1117                                                           tmp_off + tmp_found);
1118                         mlog(0, "Checking %llu against %llu\n",
1119                              (unsigned long long)blkoff,
1120                              (unsigned long long)max_block);
1121                         if (blkoff > max_block)
1122                                 return -ENOSPC;
1123                 }
1124
1125                 /* ocfs2_block_group_find_clear_bits() might
1126                  * return success, but we still want to return
1127                  * -ENOSPC unless it found the minimum number
1128                  * of bits. */
1129                 if (min_bits <= tmp_found) {
1130                         *bit_off = tmp_off;
1131                         *bits_found = tmp_found;
1132                         search = 0; /* success */
1133                 } else if (tmp_found) {
1134                         /*
1135                          * Don't show bits which we'll be returning
1136                          * for allocation to the local alloc bitmap.
1137                          */
1138                         ocfs2_local_alloc_seen_free_bits(osb, tmp_found);
1139                 }
1140         }
1141
1142         return search;
1143 }
1144
1145 static int ocfs2_block_group_search(struct inode *inode,
1146                                     struct buffer_head *group_bh,
1147                                     u32 bits_wanted, u32 min_bits,
1148                                     u64 max_block,
1149                                     u16 *bit_off, u16 *bits_found)
1150 {
1151         int ret = -ENOSPC;
1152         u64 blkoff;
1153         struct ocfs2_group_desc *bg = (struct ocfs2_group_desc *) group_bh->b_data;
1154
1155         BUG_ON(min_bits != 1);
1156         BUG_ON(ocfs2_is_cluster_bitmap(inode));
1157
1158         if (bg->bg_free_bits_count) {
1159                 ret = ocfs2_block_group_find_clear_bits(OCFS2_SB(inode->i_sb),
1160                                                         group_bh, bits_wanted,
1161                                                         le16_to_cpu(bg->bg_bits),
1162                                                         bit_off, bits_found);
1163                 if (!ret && max_block) {
1164                         blkoff = le64_to_cpu(bg->bg_blkno) + *bit_off +
1165                                 *bits_found;
1166                         mlog(0, "Checking %llu against %llu\n",
1167                              (unsigned long long)blkoff,
1168                              (unsigned long long)max_block);
1169                         if (blkoff > max_block)
1170                                 ret = -ENOSPC;
1171                 }
1172         }
1173
1174         return ret;
1175 }
1176
1177 static int ocfs2_alloc_dinode_update_counts(struct inode *inode,
1178                                        handle_t *handle,
1179                                        struct buffer_head *di_bh,
1180                                        u32 num_bits,
1181                                        u16 chain)
1182 {
1183         int ret;
1184         u32 tmp_used;
1185         struct ocfs2_dinode *di = (struct ocfs2_dinode *) di_bh->b_data;
1186         struct ocfs2_chain_list *cl = (struct ocfs2_chain_list *) &di->id2.i_chain;
1187
1188         ret = ocfs2_journal_access(handle, inode, di_bh,
1189                                    OCFS2_JOURNAL_ACCESS_WRITE);
1190         if (ret < 0) {
1191                 mlog_errno(ret);
1192                 goto out;
1193         }
1194
1195         tmp_used = le32_to_cpu(di->id1.bitmap1.i_used);
1196         di->id1.bitmap1.i_used = cpu_to_le32(num_bits + tmp_used);
1197         le32_add_cpu(&cl->cl_recs[chain].c_free, -num_bits);
1198
1199         ret = ocfs2_journal_dirty(handle, di_bh);
1200         if (ret < 0)
1201                 mlog_errno(ret);
1202
1203 out:
1204         return ret;
1205 }
1206
1207 static int ocfs2_search_one_group(struct ocfs2_alloc_context *ac,
1208                                   handle_t *handle,
1209                                   u32 bits_wanted,
1210                                   u32 min_bits,
1211                                   u16 *bit_off,
1212                                   unsigned int *num_bits,
1213                                   u64 gd_blkno,
1214                                   u16 *bits_left)
1215 {
1216         int ret;
1217         u16 found;
1218         struct buffer_head *group_bh = NULL;
1219         struct ocfs2_group_desc *gd;
1220         struct ocfs2_dinode *di = (struct ocfs2_dinode *)ac->ac_bh->b_data;
1221         struct inode *alloc_inode = ac->ac_inode;
1222
1223         ret = ocfs2_read_group_descriptor(alloc_inode, di, gd_blkno,
1224                                           &group_bh);
1225         if (ret < 0) {
1226                 mlog_errno(ret);
1227                 return ret;
1228         }
1229
1230         gd = (struct ocfs2_group_desc *) group_bh->b_data;
1231         ret = ac->ac_group_search(alloc_inode, group_bh, bits_wanted, min_bits,
1232                                   ac->ac_max_block, bit_off, &found);
1233         if (ret < 0) {
1234                 if (ret != -ENOSPC)
1235                         mlog_errno(ret);
1236                 goto out;
1237         }
1238
1239         *num_bits = found;
1240
1241         ret = ocfs2_alloc_dinode_update_counts(alloc_inode, handle, ac->ac_bh,
1242                                                *num_bits,
1243                                                le16_to_cpu(gd->bg_chain));
1244         if (ret < 0) {
1245                 mlog_errno(ret);
1246                 goto out;
1247         }
1248
1249         ret = ocfs2_block_group_set_bits(handle, alloc_inode, gd, group_bh,
1250                                          *bit_off, *num_bits);
1251         if (ret < 0)
1252                 mlog_errno(ret);
1253
1254         *bits_left = le16_to_cpu(gd->bg_free_bits_count);
1255
1256 out:
1257         brelse(group_bh);
1258
1259         return ret;
1260 }
1261
1262 static int ocfs2_search_chain(struct ocfs2_alloc_context *ac,
1263                               handle_t *handle,
1264                               u32 bits_wanted,
1265                               u32 min_bits,
1266                               u16 *bit_off,
1267                               unsigned int *num_bits,
1268                               u64 *bg_blkno,
1269                               u16 *bits_left)
1270 {
1271         int status;
1272         u16 chain, tmp_bits;
1273         u32 tmp_used;
1274         u64 next_group;
1275         struct inode *alloc_inode = ac->ac_inode;
1276         struct buffer_head *group_bh = NULL;
1277         struct buffer_head *prev_group_bh = NULL;
1278         struct ocfs2_dinode *fe = (struct ocfs2_dinode *) ac->ac_bh->b_data;
1279         struct ocfs2_chain_list *cl = (struct ocfs2_chain_list *) &fe->id2.i_chain;
1280         struct ocfs2_group_desc *bg;
1281
1282         chain = ac->ac_chain;
1283         mlog(0, "trying to alloc %u bits from chain %u, inode %llu\n",
1284              bits_wanted, chain,
1285              (unsigned long long)OCFS2_I(alloc_inode)->ip_blkno);
1286
1287         status = ocfs2_read_group_descriptor(alloc_inode, fe,
1288                                              le64_to_cpu(cl->cl_recs[chain].c_blkno),
1289                                              &group_bh);
1290         if (status < 0) {
1291                 mlog_errno(status);
1292                 goto bail;
1293         }
1294         bg = (struct ocfs2_group_desc *) group_bh->b_data;
1295
1296         status = -ENOSPC;
1297         /* for now, the chain search is a bit simplistic. We just use
1298          * the 1st group with any empty bits. */
1299         while ((status = ac->ac_group_search(alloc_inode, group_bh,
1300                                              bits_wanted, min_bits,
1301                                              ac->ac_max_block, bit_off,
1302                                              &tmp_bits)) == -ENOSPC) {
1303                 if (!bg->bg_next_group)
1304                         break;
1305
1306                 brelse(prev_group_bh);
1307                 prev_group_bh = NULL;
1308
1309                 next_group = le64_to_cpu(bg->bg_next_group);
1310                 prev_group_bh = group_bh;
1311                 group_bh = NULL;
1312                 status = ocfs2_read_group_descriptor(alloc_inode, fe,
1313                                                      next_group, &group_bh);
1314                 if (status < 0) {
1315                         mlog_errno(status);
1316                         goto bail;
1317                 }
1318                 bg = (struct ocfs2_group_desc *) group_bh->b_data;
1319         }
1320         if (status < 0) {
1321                 if (status != -ENOSPC)
1322                         mlog_errno(status);
1323                 goto bail;
1324         }
1325
1326         mlog(0, "alloc succeeds: we give %u bits from block group %llu\n",
1327              tmp_bits, (unsigned long long)le64_to_cpu(bg->bg_blkno));
1328
1329         *num_bits = tmp_bits;
1330
1331         BUG_ON(*num_bits == 0);
1332
1333         /*
1334          * Keep track of previous block descriptor read. When
1335          * we find a target, if we have read more than X
1336          * number of descriptors, and the target is reasonably
1337          * empty, relink him to top of his chain.
1338          *
1339          * We've read 0 extra blocks and only send one more to
1340          * the transaction, yet the next guy to search has a
1341          * much easier time.
1342          *
1343          * Do this *after* figuring out how many bits we're taking out
1344          * of our target group.
1345          */
1346         if (ac->ac_allow_chain_relink &&
1347             (prev_group_bh) &&
1348             (ocfs2_block_group_reasonably_empty(bg, *num_bits))) {
1349                 status = ocfs2_relink_block_group(handle, alloc_inode,
1350                                                   ac->ac_bh, group_bh,
1351                                                   prev_group_bh, chain);
1352                 if (status < 0) {
1353                         mlog_errno(status);
1354                         goto bail;
1355                 }
1356         }
1357
1358         /* Ok, claim our bits now: set the info on dinode, chainlist
1359          * and then the group */
1360         status = ocfs2_journal_access(handle,
1361                                       alloc_inode,
1362                                       ac->ac_bh,
1363                                       OCFS2_JOURNAL_ACCESS_WRITE);
1364         if (status < 0) {
1365                 mlog_errno(status);
1366                 goto bail;
1367         }
1368
1369         tmp_used = le32_to_cpu(fe->id1.bitmap1.i_used);
1370         fe->id1.bitmap1.i_used = cpu_to_le32(*num_bits + tmp_used);
1371         le32_add_cpu(&cl->cl_recs[chain].c_free, -(*num_bits));
1372
1373         status = ocfs2_journal_dirty(handle,
1374                                      ac->ac_bh);
1375         if (status < 0) {
1376                 mlog_errno(status);
1377                 goto bail;
1378         }
1379
1380         status = ocfs2_block_group_set_bits(handle,
1381                                             alloc_inode,
1382                                             bg,
1383                                             group_bh,
1384                                             *bit_off,
1385                                             *num_bits);
1386         if (status < 0) {
1387                 mlog_errno(status);
1388                 goto bail;
1389         }
1390
1391         mlog(0, "Allocated %u bits from suballocator %llu\n", *num_bits,
1392              (unsigned long long)le64_to_cpu(fe->i_blkno));
1393
1394         *bg_blkno = le64_to_cpu(bg->bg_blkno);
1395         *bits_left = le16_to_cpu(bg->bg_free_bits_count);
1396 bail:
1397         brelse(group_bh);
1398         brelse(prev_group_bh);
1399
1400         mlog_exit(status);
1401         return status;
1402 }
1403
1404 /* will give out up to bits_wanted contiguous bits. */
1405 static int ocfs2_claim_suballoc_bits(struct ocfs2_super *osb,
1406                                      struct ocfs2_alloc_context *ac,
1407                                      handle_t *handle,
1408                                      u32 bits_wanted,
1409                                      u32 min_bits,
1410                                      u16 *bit_off,
1411                                      unsigned int *num_bits,
1412                                      u64 *bg_blkno)
1413 {
1414         int status;
1415         u16 victim, i;
1416         u16 bits_left = 0;
1417         u64 hint_blkno = ac->ac_last_group;
1418         struct ocfs2_chain_list *cl;
1419         struct ocfs2_dinode *fe;
1420
1421         mlog_entry_void();
1422
1423         BUG_ON(ac->ac_bits_given >= ac->ac_bits_wanted);
1424         BUG_ON(bits_wanted > (ac->ac_bits_wanted - ac->ac_bits_given));
1425         BUG_ON(!ac->ac_bh);
1426
1427         fe = (struct ocfs2_dinode *) ac->ac_bh->b_data;
1428
1429         /* The bh was validated by the inode read during
1430          * ocfs2_reserve_suballoc_bits().  Any corruption is a code bug. */
1431         BUG_ON(!OCFS2_IS_VALID_DINODE(fe));
1432
1433         if (le32_to_cpu(fe->id1.bitmap1.i_used) >=
1434             le32_to_cpu(fe->id1.bitmap1.i_total)) {
1435                 ocfs2_error(osb->sb, "Chain allocator dinode %llu has %u used "
1436                             "bits but only %u total.",
1437                             (unsigned long long)le64_to_cpu(fe->i_blkno),
1438                             le32_to_cpu(fe->id1.bitmap1.i_used),
1439                             le32_to_cpu(fe->id1.bitmap1.i_total));
1440                 status = -EIO;
1441                 goto bail;
1442         }
1443
1444         if (hint_blkno) {
1445                 /* Attempt to short-circuit the usual search mechanism
1446                  * by jumping straight to the most recently used
1447                  * allocation group. This helps us mantain some
1448                  * contiguousness across allocations. */
1449                 status = ocfs2_search_one_group(ac, handle, bits_wanted,
1450                                                 min_bits, bit_off, num_bits,
1451                                                 hint_blkno, &bits_left);
1452                 if (!status) {
1453                         /* Be careful to update *bg_blkno here as the
1454                          * caller is expecting it to be filled in, and
1455                          * ocfs2_search_one_group() won't do that for
1456                          * us. */
1457                         *bg_blkno = hint_blkno;
1458                         goto set_hint;
1459                 }
1460                 if (status < 0 && status != -ENOSPC) {
1461                         mlog_errno(status);
1462                         goto bail;
1463                 }
1464         }
1465
1466         cl = (struct ocfs2_chain_list *) &fe->id2.i_chain;
1467
1468         victim = ocfs2_find_victim_chain(cl);
1469         ac->ac_chain = victim;
1470         ac->ac_allow_chain_relink = 1;
1471
1472         status = ocfs2_search_chain(ac, handle, bits_wanted, min_bits, bit_off,
1473                                     num_bits, bg_blkno, &bits_left);
1474         if (!status)
1475                 goto set_hint;
1476         if (status < 0 && status != -ENOSPC) {
1477                 mlog_errno(status);
1478                 goto bail;
1479         }
1480
1481         mlog(0, "Search of victim chain %u came up with nothing, "
1482              "trying all chains now.\n", victim);
1483
1484         /* If we didn't pick a good victim, then just default to
1485          * searching each chain in order. Don't allow chain relinking
1486          * because we only calculate enough journal credits for one
1487          * relink per alloc. */
1488         ac->ac_allow_chain_relink = 0;
1489         for (i = 0; i < le16_to_cpu(cl->cl_next_free_rec); i ++) {
1490                 if (i == victim)
1491                         continue;
1492                 if (!cl->cl_recs[i].c_free)
1493                         continue;
1494
1495                 ac->ac_chain = i;
1496                 status = ocfs2_search_chain(ac, handle, bits_wanted, min_bits,
1497                                             bit_off, num_bits, bg_blkno,
1498                                             &bits_left);
1499                 if (!status)
1500                         break;
1501                 if (status < 0 && status != -ENOSPC) {
1502                         mlog_errno(status);
1503                         goto bail;
1504                 }
1505         }
1506
1507 set_hint:
1508         if (status != -ENOSPC) {
1509                 /* If the next search of this group is not likely to
1510                  * yield a suitable extent, then we reset the last
1511                  * group hint so as to not waste a disk read */
1512                 if (bits_left < min_bits)
1513                         ac->ac_last_group = 0;
1514                 else
1515                         ac->ac_last_group = *bg_blkno;
1516         }
1517
1518 bail:
1519         mlog_exit(status);
1520         return status;
1521 }
1522
1523 int ocfs2_claim_metadata(struct ocfs2_super *osb,
1524                          handle_t *handle,
1525                          struct ocfs2_alloc_context *ac,
1526                          u32 bits_wanted,
1527                          u16 *suballoc_bit_start,
1528                          unsigned int *num_bits,
1529                          u64 *blkno_start)
1530 {
1531         int status;
1532         u64 bg_blkno;
1533
1534         BUG_ON(!ac);
1535         BUG_ON(ac->ac_bits_wanted < (ac->ac_bits_given + bits_wanted));
1536         BUG_ON(ac->ac_which != OCFS2_AC_USE_META);
1537
1538         status = ocfs2_claim_suballoc_bits(osb,
1539                                            ac,
1540                                            handle,
1541                                            bits_wanted,
1542                                            1,
1543                                            suballoc_bit_start,
1544                                            num_bits,
1545                                            &bg_blkno);
1546         if (status < 0) {
1547                 mlog_errno(status);
1548                 goto bail;
1549         }
1550         atomic_inc(&osb->alloc_stats.bg_allocs);
1551
1552         *blkno_start = bg_blkno + (u64) *suballoc_bit_start;
1553         ac->ac_bits_given += (*num_bits);
1554         status = 0;
1555 bail:
1556         mlog_exit(status);
1557         return status;
1558 }
1559
1560 int ocfs2_claim_new_inode(struct ocfs2_super *osb,
1561                           handle_t *handle,
1562                           struct ocfs2_alloc_context *ac,
1563                           u16 *suballoc_bit,
1564                           u64 *fe_blkno)
1565 {
1566         int status;
1567         unsigned int num_bits;
1568         u64 bg_blkno;
1569
1570         mlog_entry_void();
1571
1572         BUG_ON(!ac);
1573         BUG_ON(ac->ac_bits_given != 0);
1574         BUG_ON(ac->ac_bits_wanted != 1);
1575         BUG_ON(ac->ac_which != OCFS2_AC_USE_INODE);
1576
1577         status = ocfs2_claim_suballoc_bits(osb,
1578                                            ac,
1579                                            handle,
1580                                            1,
1581                                            1,
1582                                            suballoc_bit,
1583                                            &num_bits,
1584                                            &bg_blkno);
1585         if (status < 0) {
1586                 mlog_errno(status);
1587                 goto bail;
1588         }
1589         atomic_inc(&osb->alloc_stats.bg_allocs);
1590
1591         BUG_ON(num_bits != 1);
1592
1593         *fe_blkno = bg_blkno + (u64) (*suballoc_bit);
1594         ac->ac_bits_given++;
1595         status = 0;
1596 bail:
1597         mlog_exit(status);
1598         return status;
1599 }
1600
1601 /* translate a group desc. blkno and it's bitmap offset into
1602  * disk cluster offset. */
1603 static inline u32 ocfs2_desc_bitmap_to_cluster_off(struct inode *inode,
1604                                                    u64 bg_blkno,
1605                                                    u16 bg_bit_off)
1606 {
1607         struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
1608         u32 cluster = 0;
1609
1610         BUG_ON(!ocfs2_is_cluster_bitmap(inode));
1611
1612         if (bg_blkno != osb->first_cluster_group_blkno)
1613                 cluster = ocfs2_blocks_to_clusters(inode->i_sb, bg_blkno);
1614         cluster += (u32) bg_bit_off;
1615         return cluster;
1616 }
1617
1618 /* given a cluster offset, calculate which block group it belongs to
1619  * and return that block offset. */
1620 u64 ocfs2_which_cluster_group(struct inode *inode, u32 cluster)
1621 {
1622         struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
1623         u32 group_no;
1624
1625         BUG_ON(!ocfs2_is_cluster_bitmap(inode));
1626
1627         group_no = cluster / osb->bitmap_cpg;
1628         if (!group_no)
1629                 return osb->first_cluster_group_blkno;
1630         return ocfs2_clusters_to_blocks(inode->i_sb,
1631                                         group_no * osb->bitmap_cpg);
1632 }
1633
1634 /* given the block number of a cluster start, calculate which cluster
1635  * group and descriptor bitmap offset that corresponds to. */
1636 static inline void ocfs2_block_to_cluster_group(struct inode *inode,
1637                                                 u64 data_blkno,
1638                                                 u64 *bg_blkno,
1639                                                 u16 *bg_bit_off)
1640 {
1641         struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
1642         u32 data_cluster = ocfs2_blocks_to_clusters(osb->sb, data_blkno);
1643
1644         BUG_ON(!ocfs2_is_cluster_bitmap(inode));
1645
1646         *bg_blkno = ocfs2_which_cluster_group(inode,
1647                                               data_cluster);
1648
1649         if (*bg_blkno == osb->first_cluster_group_blkno)
1650                 *bg_bit_off = (u16) data_cluster;
1651         else
1652                 *bg_bit_off = (u16) ocfs2_blocks_to_clusters(osb->sb,
1653                                                              data_blkno - *bg_blkno);
1654 }
1655
1656 /*
1657  * min_bits - minimum contiguous chunk from this total allocation we
1658  * can handle. set to what we asked for originally for a full
1659  * contig. allocation, set to '1' to indicate we can deal with extents
1660  * of any size.
1661  */
1662 int __ocfs2_claim_clusters(struct ocfs2_super *osb,
1663                            handle_t *handle,
1664                            struct ocfs2_alloc_context *ac,
1665                            u32 min_clusters,
1666                            u32 max_clusters,
1667                            u32 *cluster_start,
1668                            u32 *num_clusters)
1669 {
1670         int status;
1671         unsigned int bits_wanted = max_clusters;
1672         u64 bg_blkno = 0;
1673         u16 bg_bit_off;
1674
1675         mlog_entry_void();
1676
1677         BUG_ON(ac->ac_bits_given >= ac->ac_bits_wanted);
1678
1679         BUG_ON(ac->ac_which != OCFS2_AC_USE_LOCAL
1680                && ac->ac_which != OCFS2_AC_USE_MAIN);
1681
1682         if (ac->ac_which == OCFS2_AC_USE_LOCAL) {
1683                 status = ocfs2_claim_local_alloc_bits(osb,
1684                                                       handle,
1685                                                       ac,
1686                                                       bits_wanted,
1687                                                       cluster_start,
1688                                                       num_clusters);
1689                 if (!status)
1690                         atomic_inc(&osb->alloc_stats.local_data);
1691         } else {
1692                 if (min_clusters > (osb->bitmap_cpg - 1)) {
1693                         /* The only paths asking for contiguousness
1694                          * should know about this already. */
1695                         mlog(ML_ERROR, "minimum allocation requested %u exceeds "
1696                              "group bitmap size %u!\n", min_clusters,
1697                              osb->bitmap_cpg);
1698                         status = -ENOSPC;
1699                         goto bail;
1700                 }
1701                 /* clamp the current request down to a realistic size. */
1702                 if (bits_wanted > (osb->bitmap_cpg - 1))
1703                         bits_wanted = osb->bitmap_cpg - 1;
1704
1705                 status = ocfs2_claim_suballoc_bits(osb,
1706                                                    ac,
1707                                                    handle,
1708                                                    bits_wanted,
1709                                                    min_clusters,
1710                                                    &bg_bit_off,
1711                                                    num_clusters,
1712                                                    &bg_blkno);
1713                 if (!status) {
1714                         *cluster_start =
1715                                 ocfs2_desc_bitmap_to_cluster_off(ac->ac_inode,
1716                                                                  bg_blkno,
1717                                                                  bg_bit_off);
1718                         atomic_inc(&osb->alloc_stats.bitmap_data);
1719                 }
1720         }
1721         if (status < 0) {
1722                 if (status != -ENOSPC)
1723                         mlog_errno(status);
1724                 goto bail;
1725         }
1726
1727         ac->ac_bits_given += *num_clusters;
1728
1729 bail:
1730         mlog_exit(status);
1731         return status;
1732 }
1733
1734 int ocfs2_claim_clusters(struct ocfs2_super *osb,
1735                          handle_t *handle,
1736                          struct ocfs2_alloc_context *ac,
1737                          u32 min_clusters,
1738                          u32 *cluster_start,
1739                          u32 *num_clusters)
1740 {
1741         unsigned int bits_wanted = ac->ac_bits_wanted - ac->ac_bits_given;
1742
1743         return __ocfs2_claim_clusters(osb, handle, ac, min_clusters,
1744                                       bits_wanted, cluster_start, num_clusters);
1745 }
1746
1747 static inline int ocfs2_block_group_clear_bits(handle_t *handle,
1748                                                struct inode *alloc_inode,
1749                                                struct ocfs2_group_desc *bg,
1750                                                struct buffer_head *group_bh,
1751                                                unsigned int bit_off,
1752                                                unsigned int num_bits)
1753 {
1754         int status;
1755         unsigned int tmp;
1756         int journal_type = OCFS2_JOURNAL_ACCESS_WRITE;
1757         struct ocfs2_group_desc *undo_bg = NULL;
1758
1759         mlog_entry_void();
1760
1761         if (!OCFS2_IS_VALID_GROUP_DESC(bg)) {
1762                 OCFS2_RO_ON_INVALID_GROUP_DESC(alloc_inode->i_sb, bg);
1763                 status = -EIO;
1764                 goto bail;
1765         }
1766
1767         mlog(0, "off = %u, num = %u\n", bit_off, num_bits);
1768
1769         if (ocfs2_is_cluster_bitmap(alloc_inode))
1770                 journal_type = OCFS2_JOURNAL_ACCESS_UNDO;
1771
1772         status = ocfs2_journal_access(handle, alloc_inode, group_bh,
1773                                       journal_type);
1774         if (status < 0) {
1775                 mlog_errno(status);
1776                 goto bail;
1777         }
1778
1779         if (ocfs2_is_cluster_bitmap(alloc_inode))
1780                 undo_bg = (struct ocfs2_group_desc *) bh2jh(group_bh)->b_committed_data;
1781
1782         tmp = num_bits;
1783         while(tmp--) {
1784                 ocfs2_clear_bit((bit_off + tmp),
1785                                 (unsigned long *) bg->bg_bitmap);
1786                 if (ocfs2_is_cluster_bitmap(alloc_inode))
1787                         ocfs2_set_bit(bit_off + tmp,
1788                                       (unsigned long *) undo_bg->bg_bitmap);
1789         }
1790         le16_add_cpu(&bg->bg_free_bits_count, num_bits);
1791
1792         status = ocfs2_journal_dirty(handle, group_bh);
1793         if (status < 0)
1794                 mlog_errno(status);
1795 bail:
1796         return status;
1797 }
1798
1799 /*
1800  * expects the suballoc inode to already be locked.
1801  */
1802 int ocfs2_free_suballoc_bits(handle_t *handle,
1803                              struct inode *alloc_inode,
1804                              struct buffer_head *alloc_bh,
1805                              unsigned int start_bit,
1806                              u64 bg_blkno,
1807                              unsigned int count)
1808 {
1809         int status = 0;
1810         u32 tmp_used;
1811         struct ocfs2_dinode *fe = (struct ocfs2_dinode *) alloc_bh->b_data;
1812         struct ocfs2_chain_list *cl = &fe->id2.i_chain;
1813         struct buffer_head *group_bh = NULL;
1814         struct ocfs2_group_desc *group;
1815
1816         mlog_entry_void();
1817
1818         /* The alloc_bh comes from ocfs2_free_dinode() or
1819          * ocfs2_free_clusters().  The callers have all locked the
1820          * allocator and gotten alloc_bh from the lock call.  This
1821          * validates the dinode buffer.  Any corruption that has happended
1822          * is a code bug. */
1823         BUG_ON(!OCFS2_IS_VALID_DINODE(fe));
1824         BUG_ON((count + start_bit) > ocfs2_bits_per_group(cl));
1825
1826         mlog(0, "%llu: freeing %u bits from group %llu, starting at %u\n",
1827              (unsigned long long)OCFS2_I(alloc_inode)->ip_blkno, count,
1828              (unsigned long long)bg_blkno, start_bit);
1829
1830         status = ocfs2_read_group_descriptor(alloc_inode, fe, bg_blkno,
1831                                              &group_bh);
1832         if (status < 0) {
1833                 mlog_errno(status);
1834                 goto bail;
1835         }
1836         group = (struct ocfs2_group_desc *) group_bh->b_data;
1837
1838         BUG_ON((count + start_bit) > le16_to_cpu(group->bg_bits));
1839
1840         status = ocfs2_block_group_clear_bits(handle, alloc_inode,
1841                                               group, group_bh,
1842                                               start_bit, count);
1843         if (status < 0) {
1844                 mlog_errno(status);
1845                 goto bail;
1846         }
1847
1848         status = ocfs2_journal_access(handle, alloc_inode, alloc_bh,
1849                                       OCFS2_JOURNAL_ACCESS_WRITE);
1850         if (status < 0) {
1851                 mlog_errno(status);
1852                 goto bail;
1853         }
1854
1855         le32_add_cpu(&cl->cl_recs[le16_to_cpu(group->bg_chain)].c_free,
1856                      count);
1857         tmp_used = le32_to_cpu(fe->id1.bitmap1.i_used);
1858         fe->id1.bitmap1.i_used = cpu_to_le32(tmp_used - count);
1859
1860         status = ocfs2_journal_dirty(handle, alloc_bh);
1861         if (status < 0) {
1862                 mlog_errno(status);
1863                 goto bail;
1864         }
1865
1866 bail:
1867         brelse(group_bh);
1868
1869         mlog_exit(status);
1870         return status;
1871 }
1872
1873 int ocfs2_free_dinode(handle_t *handle,
1874                       struct inode *inode_alloc_inode,
1875                       struct buffer_head *inode_alloc_bh,
1876                       struct ocfs2_dinode *di)
1877 {
1878         u64 blk = le64_to_cpu(di->i_blkno);
1879         u16 bit = le16_to_cpu(di->i_suballoc_bit);
1880         u64 bg_blkno = ocfs2_which_suballoc_group(blk, bit);
1881
1882         return ocfs2_free_suballoc_bits(handle, inode_alloc_inode,
1883                                         inode_alloc_bh, bit, bg_blkno, 1);
1884 }
1885
1886 int ocfs2_free_clusters(handle_t *handle,
1887                        struct inode *bitmap_inode,
1888                        struct buffer_head *bitmap_bh,
1889                        u64 start_blk,
1890                        unsigned int num_clusters)
1891 {
1892         int status;
1893         u16 bg_start_bit;
1894         u64 bg_blkno;
1895         struct ocfs2_dinode *fe;
1896
1897         /* You can't ever have a contiguous set of clusters
1898          * bigger than a block group bitmap so we never have to worry
1899          * about looping on them. */
1900
1901         mlog_entry_void();
1902
1903         /* This is expensive. We can safely remove once this stuff has
1904          * gotten tested really well. */
1905         BUG_ON(start_blk != ocfs2_clusters_to_blocks(bitmap_inode->i_sb, ocfs2_blocks_to_clusters(bitmap_inode->i_sb, start_blk)));
1906
1907         fe = (struct ocfs2_dinode *) bitmap_bh->b_data;
1908
1909         ocfs2_block_to_cluster_group(bitmap_inode, start_blk, &bg_blkno,
1910                                      &bg_start_bit);
1911
1912         mlog(0, "want to free %u clusters starting at block %llu\n",
1913              num_clusters, (unsigned long long)start_blk);
1914         mlog(0, "bg_blkno = %llu, bg_start_bit = %u\n",
1915              (unsigned long long)bg_blkno, bg_start_bit);
1916
1917         status = ocfs2_free_suballoc_bits(handle, bitmap_inode, bitmap_bh,
1918                                           bg_start_bit, bg_blkno,
1919                                           num_clusters);
1920         if (status < 0) {
1921                 mlog_errno(status);
1922                 goto out;
1923         }
1924
1925         ocfs2_local_alloc_seen_free_bits(OCFS2_SB(bitmap_inode->i_sb),
1926                                          num_clusters);
1927
1928 out:
1929         mlog_exit(status);
1930         return status;
1931 }
1932
1933 static inline void ocfs2_debug_bg(struct ocfs2_group_desc *bg)
1934 {
1935         printk("Block Group:\n");
1936         printk("bg_signature:       %s\n", bg->bg_signature);
1937         printk("bg_size:            %u\n", bg->bg_size);
1938         printk("bg_bits:            %u\n", bg->bg_bits);
1939         printk("bg_free_bits_count: %u\n", bg->bg_free_bits_count);
1940         printk("bg_chain:           %u\n", bg->bg_chain);
1941         printk("bg_generation:      %u\n", le32_to_cpu(bg->bg_generation));
1942         printk("bg_next_group:      %llu\n",
1943                (unsigned long long)bg->bg_next_group);
1944         printk("bg_parent_dinode:   %llu\n",
1945                (unsigned long long)bg->bg_parent_dinode);
1946         printk("bg_blkno:           %llu\n",
1947                (unsigned long long)bg->bg_blkno);
1948 }
1949
1950 static inline void ocfs2_debug_suballoc_inode(struct ocfs2_dinode *fe)
1951 {
1952         int i;
1953
1954         printk("Suballoc Inode %llu:\n", (unsigned long long)fe->i_blkno);
1955         printk("i_signature:                  %s\n", fe->i_signature);
1956         printk("i_size:                       %llu\n",
1957                (unsigned long long)fe->i_size);
1958         printk("i_clusters:                   %u\n", fe->i_clusters);
1959         printk("i_generation:                 %u\n",
1960                le32_to_cpu(fe->i_generation));
1961         printk("id1.bitmap1.i_used:           %u\n",
1962                le32_to_cpu(fe->id1.bitmap1.i_used));
1963         printk("id1.bitmap1.i_total:          %u\n",
1964                le32_to_cpu(fe->id1.bitmap1.i_total));
1965         printk("id2.i_chain.cl_cpg:           %u\n", fe->id2.i_chain.cl_cpg);
1966         printk("id2.i_chain.cl_bpc:           %u\n", fe->id2.i_chain.cl_bpc);
1967         printk("id2.i_chain.cl_count:         %u\n", fe->id2.i_chain.cl_count);
1968         printk("id2.i_chain.cl_next_free_rec: %u\n",
1969                fe->id2.i_chain.cl_next_free_rec);
1970         for(i = 0; i < fe->id2.i_chain.cl_next_free_rec; i++) {
1971                 printk("fe->id2.i_chain.cl_recs[%d].c_free:  %u\n", i,
1972                        fe->id2.i_chain.cl_recs[i].c_free);
1973                 printk("fe->id2.i_chain.cl_recs[%d].c_total: %u\n", i,
1974                        fe->id2.i_chain.cl_recs[i].c_total);
1975                 printk("fe->id2.i_chain.cl_recs[%d].c_blkno: %llu\n", i,
1976                        (unsigned long long)fe->id2.i_chain.cl_recs[i].c_blkno);
1977         }
1978 }
1979
1980 /*
1981  * For a given allocation, determine which allocators will need to be
1982  * accessed, and lock them, reserving the appropriate number of bits.
1983  *
1984  * Sparse file systems call this from ocfs2_write_begin_nolock()
1985  * and ocfs2_allocate_unwritten_extents().
1986  *
1987  * File systems which don't support holes call this from
1988  * ocfs2_extend_allocation().
1989  */
1990 int ocfs2_lock_allocators(struct inode *inode,
1991                           struct ocfs2_extent_tree *et,
1992                           u32 clusters_to_add, u32 extents_to_split,
1993                           struct ocfs2_alloc_context **data_ac,
1994                           struct ocfs2_alloc_context **meta_ac)
1995 {
1996         int ret = 0, num_free_extents;
1997         unsigned int max_recs_needed = clusters_to_add + 2 * extents_to_split;
1998         struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
1999
2000         *meta_ac = NULL;
2001         if (data_ac)
2002                 *data_ac = NULL;
2003
2004         BUG_ON(clusters_to_add != 0 && data_ac == NULL);
2005
2006         num_free_extents = ocfs2_num_free_extents(osb, inode, et);
2007         if (num_free_extents < 0) {
2008                 ret = num_free_extents;
2009                 mlog_errno(ret);
2010                 goto out;
2011         }
2012
2013         /*
2014          * Sparse allocation file systems need to be more conservative
2015          * with reserving room for expansion - the actual allocation
2016          * happens while we've got a journal handle open so re-taking
2017          * a cluster lock (because we ran out of room for another
2018          * extent) will violate ordering rules.
2019          *
2020          * Most of the time we'll only be seeing this 1 cluster at a time
2021          * anyway.
2022          *
2023          * Always lock for any unwritten extents - we might want to
2024          * add blocks during a split.
2025          */
2026         if (!num_free_extents ||
2027             (ocfs2_sparse_alloc(osb) && num_free_extents < max_recs_needed)) {
2028                 ret = ocfs2_reserve_new_metadata(osb, et->et_root_el, meta_ac);
2029                 if (ret < 0) {
2030                         if (ret != -ENOSPC)
2031                                 mlog_errno(ret);
2032                         goto out;
2033                 }
2034         }
2035
2036         if (clusters_to_add == 0)
2037                 goto out;
2038
2039         ret = ocfs2_reserve_clusters(osb, clusters_to_add, data_ac);
2040         if (ret < 0) {
2041                 if (ret != -ENOSPC)
2042                         mlog_errno(ret);
2043                 goto out;
2044         }
2045
2046 out:
2047         if (ret) {
2048                 if (*meta_ac) {
2049                         ocfs2_free_alloc_context(*meta_ac);
2050                         *meta_ac = NULL;
2051                 }
2052
2053                 /*
2054                  * We cannot have an error and a non null *data_ac.
2055                  */
2056         }
2057
2058         return ret;
2059 }