fs/ext4/ialloc.c

   1 /*
   2  *  linux/fs/ext4/ialloc.c
   3  *
   4  * Copyright (C) 1992, 1993, 1994, 1995
   5  * Remy Card (card@masi.ibp.fr)
   6  * Laboratoire MASI - Institut Blaise Pascal
   7  * Universite Pierre et Marie Curie (Paris VI)
   8  *
   9  *  BSD ufs-inspired inode and directory allocation by
  10  *  Stephen Tweedie (sct@redhat.com), 1993
  11  *  Big-endian to little-endian byte-swapping/bitmaps by
  12  *        David S. Miller (davem@caip.rutgers.edu), 1995
  13  */
  14
  15 #include <linux/time.h>
  16 #include <linux/fs.h>
  17 #include <linux/jbd2.h>
  18 #include <linux/stat.h>
  19 #include <linux/string.h>
  20 #include <linux/quotaops.h>
  21 #include <linux/buffer_head.h>
  22 #include <linux/random.h>
  23 #include <linux/bitops.h>
  24 #include <linux/blkdev.h>
  25 #include <asm/byteorder.h>
  26 #include "ext4.h"
  27 #include "ext4_jbd2.h"
  28 #include "xattr.h"
  29 #include "acl.h"
  30 #include "group.h"
  31
  32 /*
  33  * ialloc.c contains the inodes allocation and deallocation routines
  34  */
  35
  36 /*
  37  * The free inodes are managed by bitmaps.  A file system contains several
  38  * blocks groups.  Each group contains 1 bitmap block for blocks, 1 bitmap
  39  * block for inodes, N blocks for the inode table and data blocks.
  40  *
  41  * The file system contains group descriptors which are located after the
  42  * super block.  Each descriptor contains the number of the bitmap block and
  43  * the free blocks count in the block.
  44  */
  45
  46 /*
  47  * To avoid calling the atomic setbit hundreds or thousands of times, we only
  48  * need to use it within a single byte (to ensure we get endianness right).
  49  * We can use memset for the rest of the bitmap as there are no other users.
  50  */
  51 void mark_bitmap_end(int start_bit, int end_bit, char *bitmap)
  52 {
  53         int i;
  54
  55         if (start_bit >= end_bit)
  56                 return;
  57
  58         ext4_debug("mark end bits +%d through +%d used\n", start_bit, end_bit);
  59         for (i = start_bit; i < ((start_bit + 7) & ~7UL); i++)
  60                 ext4_set_bit(i, bitmap);
  61         if (i < end_bit)
  62                 memset(bitmap + (i >> 3), 0xff, (end_bit - i) >> 3);
  63 }
  64
  65 /* Initializes an uninitialized inode bitmap */
  66 unsigned ext4_init_inode_bitmap(struct super_block *sb, struct buffer_head *bh,
  67                                 ext4_group_t block_group,
  68                                 struct ext4_group_desc *gdp)
  69 {
  70         struct ext4_sb_info *sbi = EXT4_SB(sb);
  71
  72         J_ASSERT_BH(bh, buffer_locked(bh));
  73
  74         /* If checksum is bad mark all blocks and inodes use to prevent
  75          * allocation, essentially implementing a per-group read-only flag. */
  76         if (!ext4_group_desc_csum_verify(sbi, block_group, gdp)) {
  77                 ext4_error(sb, __func__, "Checksum bad for group %u",
  78                            block_group);
  79                 ext4_free_blks_set(sb, gdp, 0);
  80                 ext4_free_inodes_set(sb, gdp, 0);
  81                 ext4_itable_unused_set(sb, gdp, 0);
  82                 memset(bh->b_data, 0xff, sb->s_blocksize);
  83                 return 0;
  84         }
  85
  86         memset(bh->b_data, 0, (EXT4_INODES_PER_GROUP(sb) + 7) / 8);
  87         mark_bitmap_end(EXT4_INODES_PER_GROUP(sb), sb->s_blocksize * 8,
  88                         bh->b_data);
  89
  90         return EXT4_INODES_PER_GROUP(sb);
  91 }
  92
  93 /*
  94  * Read the inode allocation bitmap for a given block_group, reading
  95  * into the specified slot in the superblock's bitmap cache.
  96  *
  97  * Return buffer_head of bitmap on success or NULL.
  98  */
  99 static struct buffer_head *
 100 ext4_read_inode_bitmap(struct super_block *sb, ext4_group_t block_group)
 101 {
 102         struct ext4_group_desc *desc;
 103         struct buffer_head *bh = NULL;
 104         ext4_fsblk_t bitmap_blk;
 105
 106         desc = ext4_get_group_desc(sb, block_group, NULL);
 107         if (!desc)
 108                 return NULL;
 109         bitmap_blk = ext4_inode_bitmap(sb, desc);
 110         bh = sb_getblk(sb, bitmap_blk);
 111         if (unlikely(!bh)) {
 112                 ext4_error(sb, __func__,
 113                             "Cannot read inode bitmap - "
 114                             "block_group = %u, inode_bitmap = %llu",
 115                             block_group, bitmap_blk);
 116                 return NULL;
 117         }
 118         if (bitmap_uptodate(bh))
 119                 return bh;
 120
 121         lock_buffer(bh);
 122         if (bitmap_uptodate(bh)) {
 123                 unlock_buffer(bh);
 124                 return bh;
 125         }
 126         spin_lock(sb_bgl_lock(EXT4_SB(sb), block_group));
 127         if (desc->bg_flags & cpu_to_le16(EXT4_BG_INODE_UNINIT)) {
 128                 ext4_init_inode_bitmap(sb, bh, block_group, desc);
 129                 set_bitmap_uptodate(bh);
 130                 set_buffer_uptodate(bh);
 131                 spin_unlock(sb_bgl_lock(EXT4_SB(sb), block_group));
 132                 unlock_buffer(bh);
 133                 return bh;
 134         }
 135         spin_unlock(sb_bgl_lock(EXT4_SB(sb), block_group));
 136         if (buffer_uptodate(bh)) {
 137                 /*
 138                  * if not uninit if bh is uptodate,
 139                  * bitmap is also uptodate
 140                  */
 141                 set_bitmap_uptodate(bh);
 142                 unlock_buffer(bh);
 143                 return bh;
 144         }
 145         /*
 146          * submit the buffer_head for read. We can
 147          * safely mark the bitmap as uptodate now.
 148          * We do it here so the bitmap uptodate bit
 149          * get set with buffer lock held.
 150          */
 151         set_bitmap_uptodate(bh);
 152         if (bh_submit_read(bh) < 0) {
 153                 put_bh(bh);
 154                 ext4_error(sb, __func__,
 155                             "Cannot read inode bitmap - "
 156                             "block_group = %u, inode_bitmap = %llu",
 157                             block_group, bitmap_blk);
 158                 return NULL;
 159         }
 160         return bh;
 161 }
 162
 163 /*
 164  * NOTE! When we get the inode, we're the only people
 165  * that have access to it, and as such there are no
 166  * race conditions we have to worry about. The inode
 167  * is not on the hash-lists, and it cannot be reached
 168  * through the filesystem because the directory entry
 169  * has been deleted earlier.
 170  *
 171  * HOWEVER: we must make sure that we get no aliases,
 172  * which means that we have to call "clear_inode()"
 173  * _before_ we mark the inode not in use in the inode
 174  * bitmaps. Otherwise a newly created file might use
 175  * the same inode number (not actually the same pointer
 176  * though), and then we'd have two inodes sharing the
 177  * same inode number and space on the harddisk.
 178  */
 179 void ext4_free_inode(handle_t *handle, struct inode *inode)
 180 {
 181         struct super_block *sb = inode->i_sb;
 182         int is_directory;
 183         unsigned long ino;
 184         struct buffer_head *bitmap_bh = NULL;
 185         struct buffer_head *bh2;
 186         ext4_group_t block_group;
 187         unsigned long bit;
 188         struct ext4_group_desc *gdp;
 189         struct ext4_super_block *es;
 190         struct ext4_sb_info *sbi;
 191         int fatal = 0, err, count, cleared;
 192
 193         if (atomic_read(&inode->i_count) > 1) {
 194                 printk(KERN_ERR "ext4_free_inode: inode has count=%d\n",
 195                        atomic_read(&inode->i_count));
 196                 return;
 197         }
 198         if (inode->i_nlink) {
 199                 printk(KERN_ERR "ext4_free_inode: inode has nlink=%d\n",
 200                        inode->i_nlink);
 201                 return;
 202         }
 203         if (!sb) {
 204                 printk(KERN_ERR "ext4_free_inode: inode on "
 205                        "nonexistent device\n");
 206                 return;
 207         }
 208         sbi = EXT4_SB(sb);
 209
 210         ino = inode->i_ino;
 211         ext4_debug("freeing inode %lu\n", ino);
 212         trace_mark(ext4_free_inode,
 213                    "dev %s ino %lu mode %d uid %lu gid %lu bocks %llu",
 214                    sb->s_id, inode->i_ino, inode->i_mode,
 215                    (unsigned long) inode->i_uid, (unsigned long) inode->i_gid,
 216                    (unsigned long long) inode->i_blocks);
 217
 218         /*
 219          * Note: we must free any quota before locking the superblock,
 220          * as writing the quota to disk may need the lock as well.
 221          */
 222         vfs_dq_init(inode);
 223         ext4_xattr_delete_inode(handle, inode);
 224         vfs_dq_free_inode(inode);
 225         vfs_dq_drop(inode);
 226
 227         is_directory = S_ISDIR(inode->i_mode);
 228
 229         /* Do this BEFORE marking the inode not in use or returning an error */
 230         clear_inode(inode);
 231
 232         es = EXT4_SB(sb)->s_es;
 233         if (ino < EXT4_FIRST_INO(sb) || ino > le32_to_cpu(es->s_inodes_count)) {
 234                 ext4_error(sb, "ext4_free_inode",
 235                            "reserved or nonexistent inode %lu", ino);
 236                 goto error_return;
 237         }
 238         block_group = (ino - 1) / EXT4_INODES_PER_GROUP(sb);
 239         bit = (ino - 1) % EXT4_INODES_PER_GROUP(sb);
 240         bitmap_bh = ext4_read_inode_bitmap(sb, block_group);
 241         if (!bitmap_bh)
 242                 goto error_return;
 243
 244         BUFFER_TRACE(bitmap_bh, "get_write_access");
 245         fatal = ext4_journal_get_write_access(handle, bitmap_bh);
 246         if (fatal)
 247                 goto error_return;
 248
 249         /* Ok, now we can actually update the inode bitmaps.. */
 250         spin_lock(sb_bgl_lock(sbi, block_group));
 251         cleared = ext4_clear_bit(bit, bitmap_bh->b_data);
 252         spin_unlock(sb_bgl_lock(sbi, block_group));
 253         if (!cleared)
 254                 ext4_error(sb, "ext4_free_inode",
 255                            "bit already cleared for inode %lu", ino);
 256         else {
 257                 gdp = ext4_get_group_desc(sb, block_group, &bh2);
 258
 259                 BUFFER_TRACE(bh2, "get_write_access");
 260                 fatal = ext4_journal_get_write_access(handle, bh2);
 261                 if (fatal) goto error_return;
 262
 263                 if (gdp) {
 264                         spin_lock(sb_bgl_lock(sbi, block_group));
 265                         count = ext4_free_inodes_count(sb, gdp) + 1;
 266                         ext4_free_inodes_set(sb, gdp, count);
 267                         if (is_directory) {
 268                                 count = ext4_used_dirs_count(sb, gdp) - 1;
 269                                 ext4_used_dirs_set(sb, gdp, count);
 270                                 if (sbi->s_log_groups_per_flex) {
 271                                         ext4_group_t f;
 272
 273                                         f = ext4_flex_group(sbi, block_group);
 274                                         atomic_dec(&sbi->s_flex_groups[f].free_inodes);
 275                                 }
 276
 277                         }
 278                         gdp->bg_checksum = ext4_group_desc_csum(sbi,
 279                                                         block_group, gdp);
 280                         spin_unlock(sb_bgl_lock(sbi, block_group));
 281                         percpu_counter_inc(&sbi->s_freeinodes_counter);
 282                         if (is_directory)
 283                                 percpu_counter_dec(&sbi->s_dirs_counter);
 284
 285                         if (sbi->s_log_groups_per_flex) {
 286                                 ext4_group_t f;
 287
 288                                 f = ext4_flex_group(sbi, block_group);
 289                                 atomic_inc(&sbi->s_flex_groups[f].free_inodes);
 290                         }
 291                 }
 292                 BUFFER_TRACE(bh2, "call ext4_handle_dirty_metadata");
 293                 err = ext4_handle_dirty_metadata(handle, NULL, bh2);
 294                 if (!fatal) fatal = err;
 295         }
 296         BUFFER_TRACE(bitmap_bh, "call ext4_handle_dirty_metadata");
 297         err = ext4_handle_dirty_metadata(handle, NULL, bitmap_bh);
 298         if (!fatal)
 299                 fatal = err;
 300         sb->s_dirt = 1;
 301 error_return:
 302         brelse(bitmap_bh);
 303         ext4_std_error(sb, fatal);
 304 }
 305
 306 /*
 307  * There are two policies for allocating an inode.  If the new inode is
 308  * a directory, then a forward search is made for a block group with both
 309  * free space and a low directory-to-inode ratio; if that fails, then of
 310  * the groups with above-average free space, that group with the fewest
 311  * directories already is chosen.
 312  *
 313  * For other inodes, search forward from the parent directory\'s block
 314  * group to find a free inode.
 315  */
 316 static int find_group_dir(struct super_block *sb, struct inode *parent,
 317                                 ext4_group_t *best_group)
 318 {
 319         ext4_group_t ngroups = EXT4_SB(sb)->s_groups_count;
 320         unsigned int freei, avefreei;
 321         struct ext4_group_desc *desc, *best_desc = NULL;
 322         ext4_group_t group;
 323         int ret = -1;
 324
 325         freei = percpu_counter_read_positive(&EXT4_SB(sb)->s_freeinodes_counter);
 326         avefreei = freei / ngroups;
 327
 328         for (group = 0; group < ngroups; group++) {
 329                 desc = ext4_get_group_desc(sb, group, NULL);
 330                 if (!desc || !ext4_free_inodes_count(sb, desc))
 331                         continue;
 332                 if (ext4_free_inodes_count(sb, desc) < avefreei)
 333                         continue;
 334                 if (!best_desc ||
 335                     (ext4_free_blks_count(sb, desc) >
 336                      ext4_free_blks_count(sb, best_desc))) {
 337                         *best_group = group;
 338                         best_desc = desc;
 339                         ret = 0;
 340                 }
 341         }
 342         return ret;
 343 }
 344
 345 #define free_block_ratio 10
 346
 347 static int find_group_flex(struct super_block *sb, struct inode *parent,
 348                            ext4_group_t *best_group)
 349 {
 350         struct ext4_sb_info *sbi = EXT4_SB(sb);
 351         struct ext4_group_desc *desc;
 352         struct buffer_head *bh;
 353         struct flex_groups *flex_group = sbi->s_flex_groups;
 354         ext4_group_t parent_group = EXT4_I(parent)->i_block_group;
 355         ext4_group_t parent_fbg_group = ext4_flex_group(sbi, parent_group);
 356         ext4_group_t ngroups = sbi->s_groups_count;
 357         int flex_size = ext4_flex_bg_size(sbi);
 358         ext4_group_t best_flex = parent_fbg_group;
 359         int blocks_per_flex = sbi->s_blocks_per_group * flex_size;
 360         int flexbg_free_blocks;
 361         int flex_freeb_ratio;
 362         ext4_group_t n_fbg_groups;
 363         ext4_group_t i;
 364
 365         n_fbg_groups = (sbi->s_groups_count + flex_size - 1) >>
 366                 sbi->s_log_groups_per_flex;
 367
 368 find_close_to_parent:
 369         flexbg_free_blocks = atomic_read(&flex_group[best_flex].free_blocks);
 370         flex_freeb_ratio = flexbg_free_blocks * 100 / blocks_per_flex;
 371         if (atomic_read(&flex_group[best_flex].free_inodes) &&
 372             flex_freeb_ratio > free_block_ratio)
 373                 goto found_flexbg;
 374
 375         if (best_flex && best_flex == parent_fbg_group) {
 376                 best_flex--;
 377                 goto find_close_to_parent;
 378         }
 379
 380         for (i = 0; i < n_fbg_groups; i++) {
 381                 if (i == parent_fbg_group || i == parent_fbg_group - 1)
 382                         continue;
 383
 384                 flexbg_free_blocks = atomic_read(&flex_group[i].free_blocks);
 385                 flex_freeb_ratio = flexbg_free_blocks * 100 / blocks_per_flex;
 386
 387                 if (flex_freeb_ratio > free_block_ratio &&
 388                     (atomic_read(&flex_group[i].free_inodes))) {
 389                         best_flex = i;
 390                         goto found_flexbg;
 391                 }
 392
 393                 if ((atomic_read(&flex_group[best_flex].free_inodes) == 0) ||
 394                     ((atomic_read(&flex_group[i].free_blocks) >
 395                       atomic_read(&flex_group[best_flex].free_blocks)) &&
 396                      atomic_read(&flex_group[i].free_inodes)))
 397                         best_flex = i;
 398         }
 399
 400         if (!atomic_read(&flex_group[best_flex].free_inodes) ||
 401             !atomic_read(&flex_group[best_flex].free_blocks))
 402                 return -1;
 403
 404 found_flexbg:
 405         for (i = best_flex * flex_size; i < ngroups &&
 406                      i < (best_flex + 1) * flex_size; i++) {
 407                 desc = ext4_get_group_desc(sb, i, &bh);
 408                 if (ext4_free_inodes_count(sb, desc)) {
 409                         *best_group = i;
 410                         goto out;
 411                 }
 412         }
 413
 414         return -1;
 415 out:
 416         return 0;
 417 }
 418
 419 struct orlov_stats {
 420         __u32 free_inodes;
 421         __u32 free_blocks;
 422         __u32 used_dirs;
 423 };
 424
 425 /*
 426  * Helper function for Orlov's allocator; returns critical information
 427  * for a particular block group or flex_bg.  If flex_size is 1, then g
 428  * is a block group number; otherwise it is flex_bg number.
 429  */
 430 void get_orlov_stats(struct super_block *sb, ext4_group_t g,
 431                        int flex_size, struct orlov_stats *stats)
 432 {
 433         struct ext4_group_desc *desc;
 434         struct flex_groups *flex_group = EXT4_SB(sb)->s_flex_groups;
 435
 436         if (flex_size > 1) {
 437                 stats->free_inodes = atomic_read(&flex_group[g].free_inodes);
 438                 stats->free_blocks = atomic_read(&flex_group[g].free_blocks);
 439                 stats->used_dirs = atomic_read(&flex_group[g].used_dirs);
 440                 return;
 441         }
 442
 443         desc = ext4_get_group_desc(sb, g, NULL);
 444         if (desc) {
 445                 stats->free_inodes = ext4_free_inodes_count(sb, desc);
 446                 stats->free_blocks = ext4_free_blks_count(sb, desc);
 447                 stats->used_dirs = ext4_used_dirs_count(sb, desc);
 448         } else {
 449                 stats->free_inodes = 0;
 450                 stats->free_blocks = 0;
 451                 stats->used_dirs = 0;
 452         }
 453 }
 454
 455 /*
 456  * Orlov's allocator for directories.
 457  *
 458  * We always try to spread first-level directories.
 459  *
 460  * If there are blockgroups with both free inodes and free blocks counts
 461  * not worse than average we return one with smallest directory count.
 462  * Otherwise we simply return a random group.
 463  *
 464  * For the rest rules look so:
 465  *
 466  * It's OK to put directory into a group unless
 467  * it has too many directories already (max_dirs) or
 468  * it has too few free inodes left (min_inodes) or
 469  * it has too few free blocks left (min_blocks) or
 470  * Parent's group is preferred, if it doesn't satisfy these
 471  * conditions we search cyclically through the rest. If none
 472  * of the groups look good we just look for a group with more
 473  * free inodes than average (starting at parent's group).
 474  */
 475
 476 static int find_group_orlov(struct super_block *sb, struct inode *parent,
 477                             ext4_group_t *group, int mode)
 478 {
 479         ext4_group_t parent_group = EXT4_I(parent)->i_block_group;
 480         struct ext4_sb_info *sbi = EXT4_SB(sb);
 481         ext4_group_t ngroups = sbi->s_groups_count;
 482         int inodes_per_group = EXT4_INODES_PER_GROUP(sb);
 483         unsigned int freei, avefreei;
 484         ext4_fsblk_t freeb, avefreeb;
 485         unsigned int ndirs;
 486         int max_dirs, min_inodes;
 487         ext4_grpblk_t min_blocks;
 488         ext4_group_t i, grp, g;
 489         struct ext4_group_desc *desc;
 490         struct orlov_stats stats;
 491         int flex_size = ext4_flex_bg_size(sbi);
 492
 493         if (flex_size > 1) {
 494                 ngroups = (ngroups + flex_size - 1) >>
 495                         sbi->s_log_groups_per_flex;
 496                 parent_group >>= sbi->s_log_groups_per_flex;
 497         }
 498
 499         freei = percpu_counter_read_positive(&sbi->s_freeinodes_counter);
 500         avefreei = freei / ngroups;
 501         freeb = percpu_counter_read_positive(&sbi->s_freeblocks_counter);
 502         avefreeb = freeb;
 503         do_div(avefreeb, ngroups);
 504         ndirs = percpu_counter_read_positive(&sbi->s_dirs_counter);
 505
 506         if (S_ISDIR(mode) &&
 507             ((parent == sb->s_root->d_inode) ||
 508              (EXT4_I(parent)->i_flags & EXT4_TOPDIR_FL))) {
 509                 int best_ndir = inodes_per_group;
 510                 int ret = -1;
 511
 512                 get_random_bytes(&grp, sizeof(grp));
 513                 parent_group = (unsigned)grp % ngroups;
 514                 for (i = 0; i < ngroups; i++) {
 515                         g = (parent_group + i) % ngroups;
 516                         get_orlov_stats(sb, g, flex_size, &stats);
 517                         if (!stats.free_inodes)
 518                                 continue;
 519                         if (stats.used_dirs >= best_ndir)
 520                                 continue;
 521                         if (stats.free_inodes < avefreei)
 522                                 continue;
 523                         if (stats.free_blocks < avefreeb)
 524                                 continue;
 525                         grp = g;
 526                         ret = 0;
 527                         best_ndir = stats.used_dirs;
 528                 }
 529                 if (ret)
 530                         goto fallback;
 531         found_flex_bg:
 532                 if (flex_size == 1) {
 533                         *group = grp;
 534                         return 0;
 535                 }
 536
 537                 /*
 538                  * We pack inodes at the beginning of the flexgroup's
 539                  * inode tables.  Block allocation decisions will do
 540                  * something similar, although regular files will
 541                  * start at 2nd block group of the flexgroup.  See
 542                  * ext4_ext_find_goal() and ext4_find_near().
 543                  */
 544                 grp *= flex_size;
 545                 for (i = 0; i < flex_size; i++) {
 546                         if (grp+i >= sbi->s_groups_count)
 547                                 break;
 548                         desc = ext4_get_group_desc(sb, grp+i, NULL);
 549                         if (desc && ext4_free_inodes_count(sb, desc)) {
 550                                 *group = grp+i;
 551                                 return 0;
 552                         }
 553                 }
 554                 goto fallback;
 555         }
 556
 557         max_dirs = ndirs / ngroups + inodes_per_group / 16;
 558         min_inodes = avefreei - inodes_per_group*flex_size / 4;
 559         if (min_inodes < 1)
 560                 min_inodes = 1;
 561         min_blocks = avefreeb - EXT4_BLOCKS_PER_GROUP(sb)*flex_size / 4;
 562
 563         /*
 564          * Start looking in the flex group where we last allocated an
 565          * inode for this parent directory
 566          */
 567         if (EXT4_I(parent)->i_last_alloc_group != ~0) {
 568                 parent_group = EXT4_I(parent)->i_last_alloc_group;
 569                 if (flex_size > 1)
 570                         parent_group >>= sbi->s_log_groups_per_flex;
 571         }
 572
 573         for (i = 0; i < ngroups; i++) {
 574                 grp = (parent_group + i) % ngroups;
 575                 get_orlov_stats(sb, grp, flex_size, &stats);
 576                 if (stats.used_dirs >= max_dirs)
 577                         continue;
 578                 if (stats.free_inodes < min_inodes)
 579                         continue;
 580                 if (stats.free_blocks < min_blocks)
 581                         continue;
 582                 goto found_flex_bg;
 583         }
 584
 585 fallback:
 586         ngroups = sbi->s_groups_count;
 587         avefreei = freei / ngroups;
 588         parent_group = EXT4_I(parent)->i_block_group;
 589         for (i = 0; i < ngroups; i++) {
 590                 grp = (parent_group + i) % ngroups;
 591                 desc = ext4_get_group_desc(sb, grp, NULL);
 592                 if (desc && ext4_free_inodes_count(sb, desc) &&
 593                     ext4_free_inodes_count(sb, desc) >= avefreei) {
 594                         *group = grp;
 595                         return 0;
 596                 }
 597         }
 598
 599         if (avefreei) {
 600                 /*
 601                  * The free-inodes counter is approximate, and for really small
 602                  * filesystems the above test can fail to find any blockgroups
 603                  */
 604                 avefreei = 0;
 605                 goto fallback;
 606         }
 607
 608         return -1;
 609 }
 610
 611 static int find_group_other(struct super_block *sb, struct inode *parent,
 612                             ext4_group_t *group, int mode)
 613 {
 614         ext4_group_t parent_group = EXT4_I(parent)->i_block_group;
 615         ext4_group_t ngroups = EXT4_SB(sb)->s_groups_count;
 616         struct ext4_group_desc *desc;
 617         ext4_group_t i, last;
 618         int flex_size = ext4_flex_bg_size(EXT4_SB(sb));
 619
 620         /*
 621          * Try to place the inode is the same flex group as its
 622          * parent.  If we can't find space, use the Orlov algorithm to
 623          * find another flex group, and store that information in the
 624          * parent directory's inode information so that use that flex
 625          * group for future allocations.
 626          */
 627         if (flex_size > 1) {
 628                 int retry = 0;
 629
 630         try_again:
 631                 parent_group &= ~(flex_size-1);
 632                 last = parent_group + flex_size;
 633                 if (last > ngroups)
 634                         last = ngroups;
 635                 for  (i = parent_group; i < last; i++) {
 636                         desc = ext4_get_group_desc(sb, i, NULL);
 637                         if (desc && ext4_free_inodes_count(sb, desc)) {
 638                                 *group = i;
 639                                 return 0;
 640                         }
 641                 }
 642                 if (!retry && EXT4_I(parent)->i_last_alloc_group != ~0) {
 643                         retry = 1;
 644                         parent_group = EXT4_I(parent)->i_last_alloc_group;
 645                         goto try_again;
 646                 }
 647                 /*
 648                  * If this didn't work, use the Orlov search algorithm
 649                  * to find a new flex group; we pass in the mode to
 650                  * avoid the topdir algorithms.
 651                  */
 652                 *group = parent_group + flex_size;
 653                 if (*group > ngroups)
 654                         *group = 0;
 655                 return find_group_orlov(sb, parent, group, mode);
 656         }
 657
 658         /*
 659          * Try to place the inode in its parent directory
 660          */
 661         *group = parent_group;
 662         desc = ext4_get_group_desc(sb, *group, NULL);
 663         if (desc && ext4_free_inodes_count(sb, desc) &&
 664                         ext4_free_blks_count(sb, desc))
 665                 return 0;
 666
 667         /*
 668          * We're going to place this inode in a different blockgroup from its
 669          * parent.  We want to cause files in a common directory to all land in
 670          * the same blockgroup.  But we want files which are in a different
 671          * directory which shares a blockgroup with our parent to land in a
 672          * different blockgroup.
 673          *
 674          * So add our directory's i_ino into the starting point for the hash.
 675          */
 676         *group = (*group + parent->i_ino) % ngroups;
 677
 678         /*
 679          * Use a quadratic hash to find a group with a free inode and some free
 680          * blocks.
 681          */
 682         for (i = 1; i < ngroups; i <<= 1) {
 683                 *group += i;
 684                 if (*group >= ngroups)
 685                         *group -= ngroups;
 686                 desc = ext4_get_group_desc(sb, *group, NULL);
 687                 if (desc && ext4_free_inodes_count(sb, desc) &&
 688                                 ext4_free_blks_count(sb, desc))
 689                         return 0;
 690         }
 691
 692         /*
 693          * That failed: try linear search for a free inode, even if that group
 694          * has no free blocks.
 695          */
 696         *group = parent_group;
 697         for (i = 0; i < ngroups; i++) {
 698                 if (++*group >= ngroups)
 699                         *group = 0;
 700                 desc = ext4_get_group_desc(sb, *group, NULL);
 701                 if (desc && ext4_free_inodes_count(sb, desc))
 702                         return 0;
 703         }
 704
 705         return -1;
 706 }
 707
 708 /*
 709  * claim the inode from the inode bitmap. If the group
 710  * is uninit we need to take the groups's sb_bgl_lock
 711  * and clear the uninit flag. The inode bitmap update
 712  * and group desc uninit flag clear should be done
 713  * after holding sb_bgl_lock so that ext4_read_inode_bitmap
 714  * doesn't race with the ext4_claim_inode
 715  */
 716 static int ext4_claim_inode(struct super_block *sb,
 717                         struct buffer_head *inode_bitmap_bh,
 718                         unsigned long ino, ext4_group_t group, int mode)
 719 {
 720         int free = 0, retval = 0, count;
 721         struct ext4_sb_info *sbi = EXT4_SB(sb);
 722         struct ext4_group_desc *gdp = ext4_get_group_desc(sb, group, NULL);
 723
 724         spin_lock(sb_bgl_lock(sbi, group));
 725         if (ext4_set_bit(ino, inode_bitmap_bh->b_data)) {
 726                 /* not a free inode */
 727                 retval = 1;
 728                 goto err_ret;
 729         }
 730         ino++;
 731         if ((group == 0 && ino < EXT4_FIRST_INO(sb)) ||
 732                         ino > EXT4_INODES_PER_GROUP(sb)) {
 733                 spin_unlock(sb_bgl_lock(sbi, group));
 734                 ext4_error(sb, __func__,
 735                            "reserved inode or inode > inodes count - "
 736                            "block_group = %u, inode=%lu", group,
 737                            ino + group * EXT4_INODES_PER_GROUP(sb));
 738                 return 1;
 739         }
 740         /* If we didn't allocate from within the initialized part of the inode
 741          * table then we need to initialize up to this inode. */
 742         if (EXT4_HAS_RO_COMPAT_FEATURE(sb, EXT4_FEATURE_RO_COMPAT_GDT_CSUM)) {
 743
 744                 if (gdp->bg_flags & cpu_to_le16(EXT4_BG_INODE_UNINIT)) {
 745                         gdp->bg_flags &= cpu_to_le16(~EXT4_BG_INODE_UNINIT);
 746                         /* When marking the block group with
 747                          * ~EXT4_BG_INODE_UNINIT we don't want to depend
 748                          * on the value of bg_itable_unused even though
 749                          * mke2fs could have initialized the same for us.
 750                          * Instead we calculated the value below
 751                          */
 752
 753                         free = 0;
 754                 } else {
 755                         free = EXT4_INODES_PER_GROUP(sb) -
 756                                 ext4_itable_unused_count(sb, gdp);
 757                 }
 758
 759                 /*
 760                  * Check the relative inode number against the last used
 761                  * relative inode number in this group. if it is greater
 762                  * we need to  update the bg_itable_unused count
 763                  *
 764                  */
 765                 if (ino > free)
 766                         ext4_itable_unused_set(sb, gdp,
 767                                         (EXT4_INODES_PER_GROUP(sb) - ino));
 768         }
 769         count = ext4_free_inodes_count(sb, gdp) - 1;
 770         ext4_free_inodes_set(sb, gdp, count);
 771         if (S_ISDIR(mode)) {
 772                 count = ext4_used_dirs_count(sb, gdp) + 1;
 773                 ext4_used_dirs_set(sb, gdp, count);
 774                 if (sbi->s_log_groups_per_flex) {
 775                         ext4_group_t f = ext4_flex_group(sbi, group);
 776
 777                         atomic_inc(&sbi->s_flex_groups[f].free_inodes);
 778                 }
 779         }
 780         gdp->bg_checksum = ext4_group_desc_csum(sbi, group, gdp);
 781 err_ret:
 782         spin_unlock(sb_bgl_lock(sbi, group));
 783         return retval;
 784 }
 785
 786 /*
 787  * There are two policies for allocating an inode.  If the new inode is
 788  * a directory, then a forward search is made for a block group with both
 789  * free space and a low directory-to-inode ratio; if that fails, then of
 790  * the groups with above-average free space, that group with the fewest
 791  * directories already is chosen.
 792  *
 793  * For other inodes, search forward from the parent directory's block
 794  * group to find a free inode.
 795  */
 796 struct inode *ext4_new_inode(handle_t *handle, struct inode *dir, int mode)
 797 {
 798         struct super_block *sb;
 799         struct buffer_head *inode_bitmap_bh = NULL;
 800         struct buffer_head *group_desc_bh;
 801         ext4_group_t group = 0;
 802         unsigned long ino = 0;
 803         struct inode *inode;
 804         struct ext4_group_desc *gdp = NULL;
 805         struct ext4_super_block *es;
 806         struct ext4_inode_info *ei;
 807         struct ext4_sb_info *sbi;
 808         int ret2, err = 0;
 809         struct inode *ret;
 810         ext4_group_t i;
 811         int free = 0;
 812         static int once = 1;
 813         ext4_group_t flex_group;
 814
 815         /* Cannot create files in a deleted directory */
 816         if (!dir || !dir->i_nlink)
 817                 return ERR_PTR(-EPERM);
 818
 819         sb = dir->i_sb;
 820         trace_mark(ext4_request_inode, "dev %s dir %lu mode %d", sb->s_id,
 821                    dir->i_ino, mode);
 822         inode = new_inode(sb);
 823         if (!inode)
 824                 return ERR_PTR(-ENOMEM);
 825         ei = EXT4_I(inode);
 826
 827         sbi = EXT4_SB(sb);
 828         es = sbi->s_es;
 829
 830         if (sbi->s_log_groups_per_flex && test_opt(sb, OLDALLOC)) {
 831                 ret2 = find_group_flex(sb, dir, &group);
 832                 if (ret2 == -1) {
 833                         ret2 = find_group_other(sb, dir, &group, mode);
 834                         if (ret2 == 0 && once)
 835                                 once = 0;
 836                                 printk(KERN_NOTICE "ext4: find_group_flex "
 837                                        "failed, fallback succeeded dir %lu\n",
 838                                        dir->i_ino);
 839                 }
 840                 goto got_group;
 841         }
 842
 843         if (S_ISDIR(mode)) {
 844                 if (test_opt(sb, OLDALLOC))
 845                         ret2 = find_group_dir(sb, dir, &group);
 846                 else
 847                         ret2 = find_group_orlov(sb, dir, &group, mode);
 848         } else
 849                 ret2 = find_group_other(sb, dir, &group, mode);
 850
 851 got_group:
 852         EXT4_I(dir)->i_last_alloc_group = group;
 853         err = -ENOSPC;
 854         if (ret2 == -1)
 855                 goto out;
 856
 857         for (i = 0; i < sbi->s_groups_count; i++) {
 858                 err = -EIO;
 859
 860                 gdp = ext4_get_group_desc(sb, group, &group_desc_bh);
 861                 if (!gdp)
 862                         goto fail;
 863
 864                 brelse(inode_bitmap_bh);
 865                 inode_bitmap_bh = ext4_read_inode_bitmap(sb, group);
 866                 if (!inode_bitmap_bh)
 867                         goto fail;
 868
 869                 ino = 0;
 870
 871 repeat_in_this_group:
 872                 ino = ext4_find_next_zero_bit((unsigned long *)
 873                                               inode_bitmap_bh->b_data,
 874                                               EXT4_INODES_PER_GROUP(sb), ino);
 875
 876                 if (ino < EXT4_INODES_PER_GROUP(sb)) {
 877
 878                         BUFFER_TRACE(inode_bitmap_bh, "get_write_access");
 879                         err = ext4_journal_get_write_access(handle,
 880                                                             inode_bitmap_bh);
 881                         if (err)
 882                                 goto fail;
 883
 884                         BUFFER_TRACE(group_desc_bh, "get_write_access");
 885                         err = ext4_journal_get_write_access(handle,
 886                                                                 group_desc_bh);
 887                         if (err)
 888                                 goto fail;
 889                         if (!ext4_claim_inode(sb, inode_bitmap_bh,
 890                                                 ino, group, mode)) {
 891                                 /* we won it */
 892                                 BUFFER_TRACE(inode_bitmap_bh,
 893                                         "call ext4_handle_dirty_metadata");
 894                                 err = ext4_handle_dirty_metadata(handle,
 895                                                                  inode,
 896                                                         inode_bitmap_bh);
 897                                 if (err)
 898                                         goto fail;
 899                                 /* zero bit is inode number 1*/
 900                                 ino++;
 901                                 goto got;
 902                         }
 903                         /* we lost it */
 904                         ext4_handle_release_buffer(handle, inode_bitmap_bh);
 905                         ext4_handle_release_buffer(handle, group_desc_bh);
 906
 907                         if (++ino < EXT4_INODES_PER_GROUP(sb))
 908                                 goto repeat_in_this_group;
 909                 }
 910
 911                 /*
 912                  * This case is possible in concurrent environment.  It is very
 913                  * rare.  We cannot repeat the find_group_xxx() call because
 914                  * that will simply return the same blockgroup, because the
 915                  * group descriptor metadata has not yet been updated.
 916                  * So we just go onto the next blockgroup.
 917                  */
 918                 if (++group == sbi->s_groups_count)
 919                         group = 0;
 920         }
 921         err = -ENOSPC;
 922         goto out;
 923
 924 got:
 925         /* We may have to initialize the block bitmap if it isn't already */
 926         if (EXT4_HAS_RO_COMPAT_FEATURE(sb, EXT4_FEATURE_RO_COMPAT_GDT_CSUM) &&
 927             gdp->bg_flags & cpu_to_le16(EXT4_BG_BLOCK_UNINIT)) {
 928                 struct buffer_head *block_bitmap_bh;
 929
 930                 block_bitmap_bh = ext4_read_block_bitmap(sb, group);
 931                 BUFFER_TRACE(block_bitmap_bh, "get block bitmap access");
 932                 err = ext4_journal_get_write_access(handle, block_bitmap_bh);
 933                 if (err) {
 934                         brelse(block_bitmap_bh);
 935                         goto fail;
 936                 }
 937
 938                 free = 0;
 939                 spin_lock(sb_bgl_lock(sbi, group));
 940                 /* recheck and clear flag under lock if we still need to */
 941                 if (gdp->bg_flags & cpu_to_le16(EXT4_BG_BLOCK_UNINIT)) {
 942                         free = ext4_free_blocks_after_init(sb, group, gdp);
 943                         gdp->bg_flags &= cpu_to_le16(~EXT4_BG_BLOCK_UNINIT);
 944                         ext4_free_blks_set(sb, gdp, free);
 945                         gdp->bg_checksum = ext4_group_desc_csum(sbi, group,
 946                                                                 gdp);
 947                 }
 948                 spin_unlock(sb_bgl_lock(sbi, group));
 949
 950                 /* Don't need to dirty bitmap block if we didn't change it */
 951                 if (free) {
 952                         BUFFER_TRACE(block_bitmap_bh, "dirty block bitmap");
 953                         err = ext4_handle_dirty_metadata(handle,
 954                                                         NULL, block_bitmap_bh);
 955                 }
 956
 957                 brelse(block_bitmap_bh);
 958                 if (err)
 959                         goto fail;
 960         }
 961         BUFFER_TRACE(group_desc_bh, "call ext4_handle_dirty_metadata");
 962         err = ext4_handle_dirty_metadata(handle, NULL, group_desc_bh);
 963         if (err)
 964                 goto fail;
 965
 966         percpu_counter_dec(&sbi->s_freeinodes_counter);
 967         if (S_ISDIR(mode))
 968                 percpu_counter_inc(&sbi->s_dirs_counter);
 969         sb->s_dirt = 1;
 970
 971         if (sbi->s_log_groups_per_flex) {
 972                 flex_group = ext4_flex_group(sbi, group);
 973                 atomic_dec(&sbi->s_flex_groups[flex_group].free_inodes);
 974         }
 975
 976         inode->i_uid = current_fsuid();
 977         if (test_opt(sb, GRPID))
 978                 inode->i_gid = dir->i_gid;
 979         else if (dir->i_mode & S_ISGID) {
 980                 inode->i_gid = dir->i_gid;
 981                 if (S_ISDIR(mode))
 982                         mode |= S_ISGID;
 983         } else
 984                 inode->i_gid = current_fsgid();
 985         inode->i_mode = mode;
 986
 987         inode->i_ino = ino + group * EXT4_INODES_PER_GROUP(sb);
 988         /* This is the optimal IO size (for stat), not the fs block size */
 989         inode->i_blocks = 0;
 990         inode->i_mtime = inode->i_atime = inode->i_ctime = ei->i_crtime =
 991                                                        ext4_current_time(inode);
 992
 993         memset(ei->i_data, 0, sizeof(ei->i_data));
 994         ei->i_dir_start_lookup = 0;
 995         ei->i_disksize = 0;
 996
 997         /*
 998          * Don't inherit extent flag from directory, amongst others. We set
 999          * extent flag on newly created directory and file only if -o extent
1000          * mount option is specified
1001          */
1002         ei->i_flags =
1003                 ext4_mask_flags(mode, EXT4_I(dir)->i_flags & EXT4_FL_INHERITED);
1004         ei->i_file_acl = 0;
1005         ei->i_dtime = 0;
1006         ei->i_block_group = group;
1007         ei->i_last_alloc_group = ~0;
1008
1009         ext4_set_inode_flags(inode);
1010         if (IS_DIRSYNC(inode))
1011                 ext4_handle_sync(handle);
1012         if (insert_inode_locked(inode) < 0) {
1013                 err = -EINVAL;
1014                 goto fail_drop;
1015         }
1016         spin_lock(&sbi->s_next_gen_lock);
1017         inode->i_generation = sbi->s_next_generation++;
1018         spin_unlock(&sbi->s_next_gen_lock);
1019
1020         ei->i_state = EXT4_STATE_NEW;
1021
1022         ei->i_extra_isize = EXT4_SB(sb)->s_want_extra_isize;
1023
1024         ret = inode;
1025         if (vfs_dq_alloc_inode(inode)) {
1026                 err = -EDQUOT;
1027                 goto fail_drop;
1028         }
1029
1030         err = ext4_init_acl(handle, inode, dir);
1031         if (err)
1032                 goto fail_free_drop;
1033
1034         err = ext4_init_security(handle, inode, dir);
1035         if (err)
1036                 goto fail_free_drop;
1037
1038         if (EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_EXTENTS)) {
1039                 /* set extent flag only for directory, file and normal symlink*/
1040                 if (S_ISDIR(mode) || S_ISREG(mode) || S_ISLNK(mode)) {
1041                         EXT4_I(inode)->i_flags |= EXT4_EXTENTS_FL;
1042                         ext4_ext_tree_init(handle, inode);
1043                 }
1044         }
1045
1046         err = ext4_mark_inode_dirty(handle, inode);
1047         if (err) {
1048                 ext4_std_error(sb, err);
1049                 goto fail_free_drop;
1050         }
1051
1052         ext4_debug("allocating inode %lu\n", inode->i_ino);
1053         trace_mark(ext4_allocate_inode, "dev %s ino %lu dir %lu mode %d",
1054                    sb->s_id, inode->i_ino, dir->i_ino, mode);
1055         goto really_out;
1056 fail:
1057         ext4_std_error(sb, err);
1058 out:
1059         iput(inode);
1060         ret = ERR_PTR(err);
1061 really_out:
1062         brelse(inode_bitmap_bh);
1063         return ret;
1064
1065 fail_free_drop:
1066         vfs_dq_free_inode(inode);
1067
1068 fail_drop:
1069         vfs_dq_drop(inode);
1070         inode->i_flags |= S_NOQUOTA;
1071         inode->i_nlink = 0;
1072         unlock_new_inode(inode);
1073         iput(inode);
1074         brelse(inode_bitmap_bh);
1075         return ERR_PTR(err);
1076 }
1077
1078 /* Verify that we are loading a valid orphan from disk */
1079 struct inode *ext4_orphan_get(struct super_block *sb, unsigned long ino)
1080 {
1081         unsigned long max_ino = le32_to_cpu(EXT4_SB(sb)->s_es->s_inodes_count);
1082         ext4_group_t block_group;
1083         int bit;
1084         struct buffer_head *bitmap_bh;
1085         struct inode *inode = NULL;
1086         long err = -EIO;
1087
1088         /* Error cases - e2fsck has already cleaned up for us */
1089         if (ino > max_ino) {
1090                 ext4_warning(sb, __func__,
1091                              "bad orphan ino %lu!  e2fsck was run?", ino);
1092                 goto error;
1093         }
1094
1095         block_group = (ino - 1) / EXT4_INODES_PER_GROUP(sb);
1096         bit = (ino - 1) % EXT4_INODES_PER_GROUP(sb);
1097         bitmap_bh = ext4_read_inode_bitmap(sb, block_group);
1098         if (!bitmap_bh) {
1099                 ext4_warning(sb, __func__,
1100                              "inode bitmap error for orphan %lu", ino);
1101                 goto error;
1102         }
1103
1104         /* Having the inode bit set should be a 100% indicator that this
1105          * is a valid orphan (no e2fsck run on fs).  Orphans also include
1106          * inodes that were being truncated, so we can't check i_nlink==0.
1107          */
1108         if (!ext4_test_bit(bit, bitmap_bh->b_data))
1109                 goto bad_orphan;
1110
1111         inode = ext4_iget(sb, ino);
1112         if (IS_ERR(inode))
1113                 goto iget_failed;
1114
1115         /*
1116          * If the orphans has i_nlinks > 0 then it should be able to be
1117          * truncated, otherwise it won't be removed from the orphan list
1118          * during processing and an infinite loop will result.
1119          */
1120         if (inode->i_nlink && !ext4_can_truncate(inode))
1121                 goto bad_orphan;
1122
1123         if (NEXT_ORPHAN(inode) > max_ino)
1124                 goto bad_orphan;
1125         brelse(bitmap_bh);
1126         return inode;
1127
1128 iget_failed:
1129         err = PTR_ERR(inode);
1130         inode = NULL;
1131 bad_orphan:
1132         ext4_warning(sb, __func__,
1133                      "bad orphan inode %lu!  e2fsck was run?", ino);
1134         printk(KERN_NOTICE "ext4_test_bit(bit=%d, block=%llu) = %d\n",
1135                bit, (unsigned long long)bitmap_bh->b_blocknr,
1136                ext4_test_bit(bit, bitmap_bh->b_data));
1137         printk(KERN_NOTICE "inode=%p\n", inode);
1138         if (inode) {
1139                 printk(KERN_NOTICE "is_bad_inode(inode)=%d\n",
1140                        is_bad_inode(inode));
1141                 printk(KERN_NOTICE "NEXT_ORPHAN(inode)=%u\n",
1142                        NEXT_ORPHAN(inode));
1143                 printk(KERN_NOTICE "max_ino=%lu\n", max_ino);
1144                 printk(KERN_NOTICE "i_nlink=%u\n", inode->i_nlink);
1145                 /* Avoid freeing blocks if we got a bad deleted inode */
1146                 if (inode->i_nlink == 0)
1147                         inode->i_blocks = 0;
1148                 iput(inode);
1149         }
1150         brelse(bitmap_bh);
1151 error:
1152         return ERR_PTR(err);
1153 }
1154
1155 unsigned long ext4_count_free_inodes(struct super_block *sb)
1156 {
1157         unsigned long desc_count;
1158         struct ext4_group_desc *gdp;
1159         ext4_group_t i;
1160 #ifdef EXT4FS_DEBUG
1161         struct ext4_super_block *es;
1162         unsigned long bitmap_count, x;
1163         struct buffer_head *bitmap_bh = NULL;
1164
1165         es = EXT4_SB(sb)->s_es;
1166         desc_count = 0;
1167         bitmap_count = 0;
1168         gdp = NULL;
1169         for (i = 0; i < EXT4_SB(sb)->s_groups_count; i++) {
1170                 gdp = ext4_get_group_desc(sb, i, NULL);
1171                 if (!gdp)
1172                         continue;
1173                 desc_count += ext4_free_inodes_count(sb, gdp);
1174                 brelse(bitmap_bh);
1175                 bitmap_bh = ext4_read_inode_bitmap(sb, i);
1176                 if (!bitmap_bh)
1177                         continue;
1178
1179                 x = ext4_count_free(bitmap_bh, EXT4_INODES_PER_GROUP(sb) / 8);
1180                 printk(KERN_DEBUG "group %lu: stored = %d, counted = %lu\n",
1181                         i, ext4_free_inodes_count(sb, gdp), x);
1182                 bitmap_count += x;
1183         }
1184         brelse(bitmap_bh);
1185         printk(KERN_DEBUG "ext4_count_free_inodes: "
1186                "stored = %u, computed = %lu, %lu\n",
1187                le32_to_cpu(es->s_free_inodes_count), desc_count, bitmap_count);
1188         return desc_count;
1189 #else
1190         desc_count = 0;
1191         for (i = 0; i < EXT4_SB(sb)->s_groups_count; i++) {
1192                 gdp = ext4_get_group_desc(sb, i, NULL);
1193                 if (!gdp)
1194                         continue;
1195                 desc_count += ext4_free_inodes_count(sb, gdp);
1196                 cond_resched();
1197         }
1198         return desc_count;
1199 #endif
1200 }
1201
1202 /* Called at mount-time, super-block is locked */
1203 unsigned long ext4_count_dirs(struct super_block * sb)
1204 {
1205         unsigned long count = 0;
1206         ext4_group_t i;
1207
1208         for (i = 0; i < EXT4_SB(sb)->s_groups_count; i++) {
1209                 struct ext4_group_desc *gdp = ext4_get_group_desc(sb, i, NULL);
1210                 if (!gdp)
1211                         continue;
1212                 count += ext4_used_dirs_count(sb, gdp);
1213         }
1214         return count;
1215 }