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