fs/ext2/ialloc.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /*
   3  *  linux/fs/ext2/ialloc.c
   4  *
   5  * Copyright (C) 1992, 1993, 1994, 1995
   6  * Remy Card (card@masi.ibp.fr)
   7  * Laboratoire MASI - Institut Blaise Pascal
   8  * Universite Pierre et Marie Curie (Paris VI)
   9  *
  10  *  BSD ufs-inspired inode and directory allocation by
  11  *  Stephen Tweedie (sct@dcs.ed.ac.uk), 1993
  12  *  Big-endian to little-endian byte-swapping/bitmaps by
  13  *        David S. Miller (davem@caip.rutgers.edu), 1995
  14  */
  15
  16 #include <linux/quotaops.h>
  17 #include <linux/sched.h>
  18 #include <linux/backing-dev.h>
  19 #include <linux/buffer_head.h>
  20 #include <linux/random.h>
  21 #include "ext2.h"
  22 #include "xattr.h"
  23 #include "acl.h"
  24
  25 /*
  26  * ialloc.c contains the inodes allocation and deallocation routines
  27  */
  28
  29 /*
  30  * The free inodes are managed by bitmaps.  A file system contains several
  31  * blocks groups.  Each group contains 1 bitmap block for blocks, 1 bitmap
  32  * block for inodes, N blocks for the inode table and data blocks.
  33  *
  34  * The file system contains group descriptors which are located after the
  35  * super block.  Each descriptor contains the number of the bitmap block and
  36  * the free blocks count in the block.
  37  */
  38
  39
  40 /*
  41  * Read the inode allocation bitmap for a given block_group, reading
  42  * into the specified slot in the superblock's bitmap cache.
  43  *
  44  * Return buffer_head of bitmap on success or NULL.
  45  */
  46 static struct buffer_head *
  47 read_inode_bitmap(struct super_block * sb, unsigned long block_group)
  48 {
  49         struct ext2_group_desc *desc;
  50         struct buffer_head *bh = NULL;
  51
  52         desc = ext2_get_group_desc(sb, block_group, NULL);
  53         if (!desc)
  54                 goto error_out;
  55
  56         bh = sb_bread(sb, le32_to_cpu(desc->bg_inode_bitmap));
  57         if (!bh)
  58                 ext2_error(sb, "read_inode_bitmap",
  59                             "Cannot read inode bitmap - "
  60                             "block_group = %lu, inode_bitmap = %u",
  61                             block_group, le32_to_cpu(desc->bg_inode_bitmap));
  62 error_out:
  63         return bh;
  64 }
  65
  66 static void ext2_release_inode(struct super_block *sb, int group, int dir)
  67 {
  68         struct ext2_group_desc * desc;
  69         struct buffer_head *bh;
  70
  71         desc = ext2_get_group_desc(sb, group, &bh);
  72         if (!desc) {
  73                 ext2_error(sb, "ext2_release_inode",
  74                         "can't get descriptor for group %d", group);
  75                 return;
  76         }
  77
  78         spin_lock(sb_bgl_lock(EXT2_SB(sb), group));
  79         le16_add_cpu(&desc->bg_free_inodes_count, 1);
  80         if (dir)
  81                 le16_add_cpu(&desc->bg_used_dirs_count, -1);
  82         spin_unlock(sb_bgl_lock(EXT2_SB(sb), group));
  83         if (dir)
  84                 percpu_counter_dec(&EXT2_SB(sb)->s_dirs_counter);
  85         mark_buffer_dirty(bh);
  86 }
  87
  88 /*
  89  * NOTE! When we get the inode, we're the only people
  90  * that have access to it, and as such there are no
  91  * race conditions we have to worry about. The inode
  92  * is not on the hash-lists, and it cannot be reached
  93  * through the filesystem because the directory entry
  94  * has been deleted earlier.
  95  *
  96  * HOWEVER: we must make sure that we get no aliases,
  97  * which means that we have to call "clear_inode()"
  98  * _before_ we mark the inode not in use in the inode
  99  * bitmaps. Otherwise a newly created file might use
 100  * the same inode number (not actually the same pointer
 101  * though), and then we'd have two inodes sharing the
 102  * same inode number and space on the harddisk.
 103  */
 104 void ext2_free_inode (struct inode * inode)
 105 {
 106         struct super_block * sb = inode->i_sb;
 107         int is_directory;
 108         unsigned long ino;
 109         struct buffer_head *bitmap_bh;
 110         unsigned long block_group;
 111         unsigned long bit;
 112         struct ext2_super_block * es;
 113
 114         ino = inode->i_ino;
 115         ext2_debug ("freeing inode %lu\n", ino);
 116
 117         /*
 118          * Note: we must free any quota before locking the superblock,
 119          * as writing the quota to disk may need the lock as well.
 120          */
 121         /* Quota is already initialized in iput() */
 122         dquot_free_inode(inode);
 123         dquot_drop(inode);
 124
 125         es = EXT2_SB(sb)->s_es;
 126         is_directory = S_ISDIR(inode->i_mode);
 127
 128         if (ino < EXT2_FIRST_INO(sb) ||
 129             ino > le32_to_cpu(es->s_inodes_count)) {
 130                 ext2_error (sb, "ext2_free_inode",
 131                             "reserved or nonexistent inode %lu", ino);
 132                 return;
 133         }
 134         block_group = (ino - 1) / EXT2_INODES_PER_GROUP(sb);
 135         bit = (ino - 1) % EXT2_INODES_PER_GROUP(sb);
 136         bitmap_bh = read_inode_bitmap(sb, block_group);
 137         if (!bitmap_bh)
 138                 return;
 139
 140         /* Ok, now we can actually update the inode bitmaps.. */
 141         if (!ext2_clear_bit_atomic(sb_bgl_lock(EXT2_SB(sb), block_group),
 142                                 bit, (void *) bitmap_bh->b_data))
 143                 ext2_error (sb, "ext2_free_inode",
 144                               "bit already cleared for inode %lu", ino);
 145         else
 146                 ext2_release_inode(sb, block_group, is_directory);
 147         mark_buffer_dirty(bitmap_bh);
 148         if (sb->s_flags & MS_SYNCHRONOUS)
 149                 sync_dirty_buffer(bitmap_bh);
 150
 151         brelse(bitmap_bh);
 152 }
 153
 154 /*
 155  * We perform asynchronous prereading of the new inode's inode block when
 156  * we create the inode, in the expectation that the inode will be written
 157  * back soon.  There are two reasons:
 158  *
 159  * - When creating a large number of files, the async prereads will be
 160  *   nicely merged into large reads
 161  * - When writing out a large number of inodes, we don't need to keep on
 162  *   stalling the writes while we read the inode block.
 163  *
 164  * FIXME: ext2_get_group_desc() needs to be simplified.
 165  */
 166 static void ext2_preread_inode(struct inode *inode)
 167 {
 168         unsigned long block_group;
 169         unsigned long offset;
 170         unsigned long block;
 171         struct ext2_group_desc * gdp;
 172         struct backing_dev_info *bdi;
 173
 174         bdi = inode_to_bdi(inode);
 175         if (bdi_read_congested(bdi))
 176                 return;
 177         if (bdi_write_congested(bdi))
 178                 return;
 179
 180         block_group = (inode->i_ino - 1) / EXT2_INODES_PER_GROUP(inode->i_sb);
 181         gdp = ext2_get_group_desc(inode->i_sb, block_group, NULL);
 182         if (gdp == NULL)
 183                 return;
 184
 185         /*
 186          * Figure out the offset within the block group inode table
 187          */
 188         offset = ((inode->i_ino - 1) % EXT2_INODES_PER_GROUP(inode->i_sb)) *
 189                                 EXT2_INODE_SIZE(inode->i_sb);
 190         block = le32_to_cpu(gdp->bg_inode_table) +
 191                                 (offset >> EXT2_BLOCK_SIZE_BITS(inode->i_sb));
 192         sb_breadahead(inode->i_sb, block);
 193 }
 194
 195 /*
 196  * There are two policies for allocating an inode.  If the new inode is
 197  * a directory, then a forward search is made for a block group with both
 198  * free space and a low directory-to-inode ratio; if that fails, then of
 199  * the groups with above-average free space, that group with the fewest
 200  * directories already is chosen.
 201  *
 202  * For other inodes, search forward from the parent directory\'s block
 203  * group to find a free inode.
 204  */
 205 static int find_group_dir(struct super_block *sb, struct inode *parent)
 206 {
 207         int ngroups = EXT2_SB(sb)->s_groups_count;
 208         int avefreei = ext2_count_free_inodes(sb) / ngroups;
 209         struct ext2_group_desc *desc, *best_desc = NULL;
 210         int group, best_group = -1;
 211
 212         for (group = 0; group < ngroups; group++) {
 213                 desc = ext2_get_group_desc (sb, group, NULL);
 214                 if (!desc || !desc->bg_free_inodes_count)
 215                         continue;
 216                 if (le16_to_cpu(desc->bg_free_inodes_count) < avefreei)
 217                         continue;
 218                 if (!best_desc ||
 219                     (le16_to_cpu(desc->bg_free_blocks_count) >
 220                      le16_to_cpu(best_desc->bg_free_blocks_count))) {
 221                         best_group = group;
 222                         best_desc = desc;
 223                 }
 224         }
 225         if (!best_desc)
 226                 return -1;
 227
 228         return best_group;
 229 }
 230
 231 /*
 232  * Orlov's allocator for directories.
 233  *
 234  * We always try to spread first-level directories.
 235  *
 236  * If there are blockgroups with both free inodes and free blocks counts
 237  * not worse than average we return one with smallest directory count.
 238  * Otherwise we simply return a random group.
 239  *
 240  * For the rest rules look so:
 241  *
 242  * It's OK to put directory into a group unless
 243  * it has too many directories already (max_dirs) or
 244  * it has too few free inodes left (min_inodes) or
 245  * it has too few free blocks left (min_blocks) or
 246  * it's already running too large debt (max_debt).
 247  * Parent's group is preferred, if it doesn't satisfy these
 248  * conditions we search cyclically through the rest. If none
 249  * of the groups look good we just look for a group with more
 250  * free inodes than average (starting at parent's group).
 251  *
 252  * Debt is incremented each time we allocate a directory and decremented
 253  * when we allocate an inode, within 0--255.
 254  */
 255
 256 #define INODE_COST 64
 257 #define BLOCK_COST 256
 258
 259 static int find_group_orlov(struct super_block *sb, struct inode *parent)
 260 {
 261         int parent_group = EXT2_I(parent)->i_block_group;
 262         struct ext2_sb_info *sbi = EXT2_SB(sb);
 263         struct ext2_super_block *es = sbi->s_es;
 264         int ngroups = sbi->s_groups_count;
 265         int inodes_per_group = EXT2_INODES_PER_GROUP(sb);
 266         int freei;
 267         int avefreei;
 268         int free_blocks;
 269         int avefreeb;
 270         int blocks_per_dir;
 271         int ndirs;
 272         int max_debt, max_dirs, min_blocks, min_inodes;
 273         int group = -1, i;
 274         struct ext2_group_desc *desc;
 275
 276         freei = percpu_counter_read_positive(&sbi->s_freeinodes_counter);
 277         avefreei = freei / ngroups;
 278         free_blocks = percpu_counter_read_positive(&sbi->s_freeblocks_counter);
 279         avefreeb = free_blocks / ngroups;
 280         ndirs = percpu_counter_read_positive(&sbi->s_dirs_counter);
 281
 282         if ((parent == d_inode(sb->s_root)) ||
 283             (EXT2_I(parent)->i_flags & EXT2_TOPDIR_FL)) {
 284                 struct ext2_group_desc *best_desc = NULL;
 285                 int best_ndir = inodes_per_group;
 286                 int best_group = -1;
 287
 288                 group = prandom_u32();
 289                 parent_group = (unsigned)group % ngroups;
 290                 for (i = 0; i < ngroups; i++) {
 291                         group = (parent_group + i) % ngroups;
 292                         desc = ext2_get_group_desc (sb, group, NULL);
 293                         if (!desc || !desc->bg_free_inodes_count)
 294                                 continue;
 295                         if (le16_to_cpu(desc->bg_used_dirs_count) >= best_ndir)
 296                                 continue;
 297                         if (le16_to_cpu(desc->bg_free_inodes_count) < avefreei)
 298                                 continue;
 299                         if (le16_to_cpu(desc->bg_free_blocks_count) < avefreeb)
 300                                 continue;
 301                         best_group = group;
 302                         best_ndir = le16_to_cpu(desc->bg_used_dirs_count);
 303                         best_desc = desc;
 304                 }
 305                 if (best_group >= 0) {
 306                         desc = best_desc;
 307                         group = best_group;
 308                         goto found;
 309                 }
 310                 goto fallback;
 311         }
 312
 313         if (ndirs == 0)
 314                 ndirs = 1;      /* percpu_counters are approximate... */
 315
 316         blocks_per_dir = (le32_to_cpu(es->s_blocks_count)-free_blocks) / ndirs;
 317
 318         max_dirs = ndirs / ngroups + inodes_per_group / 16;
 319         min_inodes = avefreei - inodes_per_group / 4;
 320         min_blocks = avefreeb - EXT2_BLOCKS_PER_GROUP(sb) / 4;
 321
 322         max_debt = EXT2_BLOCKS_PER_GROUP(sb) / max(blocks_per_dir, BLOCK_COST);
 323         if (max_debt * INODE_COST > inodes_per_group)
 324                 max_debt = inodes_per_group / INODE_COST;
 325         if (max_debt > 255)
 326                 max_debt = 255;
 327         if (max_debt == 0)
 328                 max_debt = 1;
 329
 330         for (i = 0; i < ngroups; i++) {
 331                 group = (parent_group + i) % ngroups;
 332                 desc = ext2_get_group_desc (sb, group, NULL);
 333                 if (!desc || !desc->bg_free_inodes_count)
 334                         continue;
 335                 if (sbi->s_debts[group] >= max_debt)
 336                         continue;
 337                 if (le16_to_cpu(desc->bg_used_dirs_count) >= max_dirs)
 338                         continue;
 339                 if (le16_to_cpu(desc->bg_free_inodes_count) < min_inodes)
 340                         continue;
 341                 if (le16_to_cpu(desc->bg_free_blocks_count) < min_blocks)
 342                         continue;
 343                 goto found;
 344         }
 345
 346 fallback:
 347         for (i = 0; i < ngroups; i++) {
 348                 group = (parent_group + i) % ngroups;
 349                 desc = ext2_get_group_desc (sb, group, NULL);
 350                 if (!desc || !desc->bg_free_inodes_count)
 351                         continue;
 352                 if (le16_to_cpu(desc->bg_free_inodes_count) >= avefreei)
 353                         goto found;
 354         }
 355
 356         if (avefreei) {
 357                 /*
 358                  * The free-inodes counter is approximate, and for really small
 359                  * filesystems the above test can fail to find any blockgroups
 360                  */
 361                 avefreei = 0;
 362                 goto fallback;
 363         }
 364
 365         return -1;
 366
 367 found:
 368         return group;
 369 }
 370
 371 static int find_group_other(struct super_block *sb, struct inode *parent)
 372 {
 373         int parent_group = EXT2_I(parent)->i_block_group;
 374         int ngroups = EXT2_SB(sb)->s_groups_count;
 375         struct ext2_group_desc *desc;
 376         int group, i;
 377
 378         /*
 379          * Try to place the inode in its parent directory
 380          */
 381         group = parent_group;
 382         desc = ext2_get_group_desc (sb, group, NULL);
 383         if (desc && le16_to_cpu(desc->bg_free_inodes_count) &&
 384                         le16_to_cpu(desc->bg_free_blocks_count))
 385                 goto found;
 386
 387         /*
 388          * We're going to place this inode in a different blockgroup from its
 389          * parent.  We want to cause files in a common directory to all land in
 390          * the same blockgroup.  But we want files which are in a different
 391          * directory which shares a blockgroup with our parent to land in a
 392          * different blockgroup.
 393          *
 394          * So add our directory's i_ino into the starting point for the hash.
 395          */
 396         group = (group + parent->i_ino) % ngroups;
 397
 398         /*
 399          * Use a quadratic hash to find a group with a free inode and some
 400          * free blocks.
 401          */
 402         for (i = 1; i < ngroups; i <<= 1) {
 403                 group += i;
 404                 if (group >= ngroups)
 405                         group -= ngroups;
 406                 desc = ext2_get_group_desc (sb, group, NULL);
 407                 if (desc && le16_to_cpu(desc->bg_free_inodes_count) &&
 408                                 le16_to_cpu(desc->bg_free_blocks_count))
 409                         goto found;
 410         }
 411
 412         /*
 413          * That failed: try linear search for a free inode, even if that group
 414          * has no free blocks.
 415          */
 416         group = parent_group;
 417         for (i = 0; i < ngroups; i++) {
 418                 if (++group >= ngroups)
 419                         group = 0;
 420                 desc = ext2_get_group_desc (sb, group, NULL);
 421                 if (desc && le16_to_cpu(desc->bg_free_inodes_count))
 422                         goto found;
 423         }
 424
 425         return -1;
 426
 427 found:
 428         return group;
 429 }
 430
 431 struct inode *ext2_new_inode(struct inode *dir, umode_t mode,
 432                              const struct qstr *qstr)
 433 {
 434         struct super_block *sb;
 435         struct buffer_head *bitmap_bh = NULL;
 436         struct buffer_head *bh2;
 437         int group, i;
 438         ino_t ino = 0;
 439         struct inode * inode;
 440         struct ext2_group_desc *gdp;
 441         struct ext2_super_block *es;
 442         struct ext2_inode_info *ei;
 443         struct ext2_sb_info *sbi;
 444         int err;
 445
 446         sb = dir->i_sb;
 447         inode = new_inode(sb);
 448         if (!inode)
 449                 return ERR_PTR(-ENOMEM);
 450
 451         ei = EXT2_I(inode);
 452         sbi = EXT2_SB(sb);
 453         es = sbi->s_es;
 454         if (S_ISDIR(mode)) {
 455                 if (test_opt(sb, OLDALLOC))
 456                         group = find_group_dir(sb, dir);
 457                 else
 458                         group = find_group_orlov(sb, dir);
 459         } else
 460                 group = find_group_other(sb, dir);
 461
 462         if (group == -1) {
 463                 err = -ENOSPC;
 464                 goto fail;
 465         }
 466
 467         for (i = 0; i < sbi->s_groups_count; i++) {
 468                 gdp = ext2_get_group_desc(sb, group, &bh2);
 469                 if (!gdp) {
 470                         if (++group == sbi->s_groups_count)
 471                                 group = 0;
 472                         continue;
 473                 }
 474                 brelse(bitmap_bh);
 475                 bitmap_bh = read_inode_bitmap(sb, group);
 476                 if (!bitmap_bh) {
 477                         err = -EIO;
 478                         goto fail;
 479                 }
 480                 ino = 0;
 481
 482 repeat_in_this_group:
 483                 ino = ext2_find_next_zero_bit((unsigned long *)bitmap_bh->b_data,
 484                                               EXT2_INODES_PER_GROUP(sb), ino);
 485                 if (ino >= EXT2_INODES_PER_GROUP(sb)) {
 486                         /*
 487                          * Rare race: find_group_xx() decided that there were
 488                          * free inodes in this group, but by the time we tried
 489                          * to allocate one, they're all gone.  This can also
 490                          * occur because the counters which find_group_orlov()
 491                          * uses are approximate.  So just go and search the
 492                          * next block group.
 493                          */
 494                         if (++group == sbi->s_groups_count)
 495                                 group = 0;
 496                         continue;
 497                 }
 498                 if (ext2_set_bit_atomic(sb_bgl_lock(sbi, group),
 499                                                 ino, bitmap_bh->b_data)) {
 500                         /* we lost this inode */
 501                         if (++ino >= EXT2_INODES_PER_GROUP(sb)) {
 502                                 /* this group is exhausted, try next group */
 503                                 if (++group == sbi->s_groups_count)
 504                                         group = 0;
 505                                 continue;
 506                         }
 507                         /* try to find free inode in the same group */
 508                         goto repeat_in_this_group;
 509                 }
 510                 goto got;
 511         }
 512
 513         /*
 514          * Scanned all blockgroups.
 515          */
 516         err = -ENOSPC;
 517         goto fail;
 518 got:
 519         mark_buffer_dirty(bitmap_bh);
 520         if (sb->s_flags & MS_SYNCHRONOUS)
 521                 sync_dirty_buffer(bitmap_bh);
 522         brelse(bitmap_bh);
 523
 524         ino += group * EXT2_INODES_PER_GROUP(sb) + 1;
 525         if (ino < EXT2_FIRST_INO(sb) || ino > le32_to_cpu(es->s_inodes_count)) {
 526                 ext2_error (sb, "ext2_new_inode",
 527                             "reserved inode or inode > inodes count - "
 528                             "block_group = %d,inode=%lu", group,
 529                             (unsigned long) ino);
 530                 err = -EIO;
 531                 goto fail;
 532         }
 533
 534         percpu_counter_add(&sbi->s_freeinodes_counter, -1);
 535         if (S_ISDIR(mode))
 536                 percpu_counter_inc(&sbi->s_dirs_counter);
 537
 538         spin_lock(sb_bgl_lock(sbi, group));
 539         le16_add_cpu(&gdp->bg_free_inodes_count, -1);
 540         if (S_ISDIR(mode)) {
 541                 if (sbi->s_debts[group] < 255)
 542                         sbi->s_debts[group]++;
 543                 le16_add_cpu(&gdp->bg_used_dirs_count, 1);
 544         } else {
 545                 if (sbi->s_debts[group])
 546                         sbi->s_debts[group]--;
 547         }
 548         spin_unlock(sb_bgl_lock(sbi, group));
 549
 550         mark_buffer_dirty(bh2);
 551         if (test_opt(sb, GRPID)) {
 552                 inode->i_mode = mode;
 553                 inode->i_uid = current_fsuid();
 554                 inode->i_gid = dir->i_gid;
 555         } else
 556                 inode_init_owner(inode, dir, mode);
 557
 558         inode->i_ino = ino;
 559         inode->i_blocks = 0;
 560         inode->i_mtime = inode->i_atime = inode->i_ctime = current_time(inode);
 561         memset(ei->i_data, 0, sizeof(ei->i_data));
 562         ei->i_flags =
 563                 ext2_mask_flags(mode, EXT2_I(dir)->i_flags & EXT2_FL_INHERITED);
 564         ei->i_faddr = 0;
 565         ei->i_frag_no = 0;
 566         ei->i_frag_size = 0;
 567         ei->i_file_acl = 0;
 568         ei->i_dir_acl = 0;
 569         ei->i_dtime = 0;
 570         ei->i_block_alloc_info = NULL;
 571         ei->i_block_group = group;
 572         ei->i_dir_start_lookup = 0;
 573         ei->i_state = EXT2_STATE_NEW;
 574         ext2_set_inode_flags(inode);
 575         spin_lock(&sbi->s_next_gen_lock);
 576         inode->i_generation = sbi->s_next_generation++;
 577         spin_unlock(&sbi->s_next_gen_lock);
 578         if (insert_inode_locked(inode) < 0) {
 579                 ext2_error(sb, "ext2_new_inode",
 580                            "inode number already in use - inode=%lu",
 581                            (unsigned long) ino);
 582                 err = -EIO;
 583                 goto fail;
 584         }
 585
 586         err = dquot_initialize(inode);
 587         if (err)
 588                 goto fail_drop;
 589
 590         err = dquot_alloc_inode(inode);
 591         if (err)
 592                 goto fail_drop;
 593
 594         err = ext2_init_acl(inode, dir);
 595         if (err)
 596                 goto fail_free_drop;
 597
 598         err = ext2_init_security(inode, dir, qstr);
 599         if (err)
 600                 goto fail_free_drop;
 601
 602         mark_inode_dirty(inode);
 603         ext2_debug("allocating inode %lu\n", inode->i_ino);
 604         ext2_preread_inode(inode);
 605         return inode;
 606
 607 fail_free_drop:
 608         dquot_free_inode(inode);
 609
 610 fail_drop:
 611         dquot_drop(inode);
 612         inode->i_flags |= S_NOQUOTA;
 613         clear_nlink(inode);
 614         unlock_new_inode(inode);
 615         iput(inode);
 616         return ERR_PTR(err);
 617
 618 fail:
 619         make_bad_inode(inode);
 620         iput(inode);
 621         return ERR_PTR(err);
 622 }
 623
 624 unsigned long ext2_count_free_inodes (struct super_block * sb)
 625 {
 626         struct ext2_group_desc *desc;
 627         unsigned long desc_count = 0;
 628         int i;
 629
 630 #ifdef EXT2FS_DEBUG
 631         struct ext2_super_block *es;
 632         unsigned long bitmap_count = 0;
 633         struct buffer_head *bitmap_bh = NULL;
 634
 635         es = EXT2_SB(sb)->s_es;
 636         for (i = 0; i < EXT2_SB(sb)->s_groups_count; i++) {
 637                 unsigned x;
 638
 639                 desc = ext2_get_group_desc (sb, i, NULL);
 640                 if (!desc)
 641                         continue;
 642                 desc_count += le16_to_cpu(desc->bg_free_inodes_count);
 643                 brelse(bitmap_bh);
 644                 bitmap_bh = read_inode_bitmap(sb, i);
 645                 if (!bitmap_bh)
 646                         continue;
 647
 648                 x = ext2_count_free(bitmap_bh, EXT2_INODES_PER_GROUP(sb) / 8);
 649                 printk("group %d: stored = %d, counted = %u\n",
 650                         i, le16_to_cpu(desc->bg_free_inodes_count), x);
 651                 bitmap_count += x;
 652         }
 653         brelse(bitmap_bh);
 654         printk("ext2_count_free_inodes: stored = %lu, computed = %lu, %lu\n",
 655                 (unsigned long)
 656                 percpu_counter_read(&EXT2_SB(sb)->s_freeinodes_counter),
 657                 desc_count, bitmap_count);
 658         return desc_count;
 659 #else
 660         for (i = 0; i < EXT2_SB(sb)->s_groups_count; i++) {
 661                 desc = ext2_get_group_desc (sb, i, NULL);
 662                 if (!desc)
 663                         continue;
 664                 desc_count += le16_to_cpu(desc->bg_free_inodes_count);
 665         }
 666         return desc_count;
 667 #endif
 668 }
 669
 670 /* Called at mount-time, super-block is locked */
 671 unsigned long ext2_count_dirs (struct super_block * sb)
 672 {
 673         unsigned long count = 0;
 674         int i;
 675
 676         for (i = 0; i < EXT2_SB(sb)->s_groups_count; i++) {
 677                 struct ext2_group_desc *gdp = ext2_get_group_desc (sb, i, NULL);
 678                 if (!gdp)
 679                         continue;
 680                 count += le16_to_cpu(gdp->bg_used_dirs_count);
 681         }
 682         return count;
 683 }
 684