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
  27 #include "ext4.h"
  28 #include "ext4_jbd2.h"
  29 #include "xattr.h"
  30 #include "acl.h"
  31
  32 #include <trace/events/ext4.h>
  33
  34 /*
  35  * ialloc.c contains the inodes allocation and deallocation routines
  36  */
  37
  38 /*
  39  * The free inodes are managed by bitmaps.  A file system contains several
  40  * blocks groups.  Each group contains 1 bitmap block for blocks, 1 bitmap
  41  * block for inodes, N blocks for the inode table and data blocks.
  42  *
  43  * The file system contains group descriptors which are located after the
  44  * super block.  Each descriptor contains the number of the bitmap block and
  45  * the free blocks count in the block.
  46  */
  47
  48 /*
  49  * To avoid calling the atomic setbit hundreds or thousands of times, we only
  50  * need to use it within a single byte (to ensure we get endianness right).
  51  * We can use memset for the rest of the bitmap as there are no other users.
  52  */
  53 void mark_bitmap_end(int start_bit, int end_bit, char *bitmap)
  54 {
  55         int i;
  56
  57         if (start_bit >= end_bit)
  58                 return;
  59
  60         ext4_debug("mark end bits +%d through +%d used\n", start_bit, end_bit);
  61         for (i = start_bit; i < ((start_bit + 7) & ~7UL); i++)
  62                 ext4_set_bit(i, bitmap);
  63         if (i < end_bit)
  64                 memset(bitmap + (i >> 3), 0xff, (end_bit - i) >> 3);
  65 }
  66
  67 /* Initializes an uninitialized inode bitmap */
  68 unsigned ext4_init_inode_bitmap(struct super_block *sb, struct buffer_head *bh,
  69                                 ext4_group_t block_group,
  70                                 struct ext4_group_desc *gdp)
  71 {
  72         struct ext4_sb_info *sbi = EXT4_SB(sb);
  73
  74         J_ASSERT_BH(bh, buffer_locked(bh));
  75
  76         /* If checksum is bad mark all blocks and inodes use to prevent
  77          * allocation, essentially implementing a per-group read-only flag. */
  78         if (!ext4_group_desc_csum_verify(sbi, block_group, gdp)) {
  79                 ext4_error(sb, "Checksum bad for group %u", block_group);
  80                 ext4_free_blks_set(sb, gdp, 0);
  81                 ext4_free_inodes_set(sb, gdp, 0);
  82                 ext4_itable_unused_set(sb, gdp, 0);
  83                 memset(bh->b_data, 0xff, sb->s_blocksize);
  84                 return 0;
  85         }
  86
  87         memset(bh->b_data, 0, (EXT4_INODES_PER_GROUP(sb) + 7) / 8);
  88         mark_bitmap_end(EXT4_INODES_PER_GROUP(sb), sb->s_blocksize * 8,
  89                         bh->b_data);
  90
  91         return EXT4_INODES_PER_GROUP(sb);
  92 }
  93
  94 /*
  95  * Read the inode allocation bitmap for a given block_group, reading
  96  * into the specified slot in the superblock's bitmap cache.
  97  *
  98  * Return buffer_head of bitmap on success or NULL.
  99  */
 100 static struct buffer_head *
 101 ext4_read_inode_bitmap(struct super_block *sb, ext4_group_t block_group)
 102 {
 103         struct ext4_group_desc *desc;
 104         struct buffer_head *bh = NULL;
 105         ext4_fsblk_t bitmap_blk;
 106
 107         desc = ext4_get_group_desc(sb, block_group, NULL);
 108         if (!desc)
 109                 return NULL;
 110         bitmap_blk = ext4_inode_bitmap(sb, desc);
 111         bh = sb_getblk(sb, bitmap_blk);
 112         if (unlikely(!bh)) {
 113                 ext4_error(sb, "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         ext4_lock_group(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                 ext4_unlock_group(sb, block_group);
 132                 unlock_buffer(bh);
 133                 return bh;
 134         }
 135         ext4_unlock_group(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, "Cannot read inode bitmap - "
 155                             "block_group = %u, inode_bitmap = %llu",
 156                             block_group, bitmap_blk);
 157                 return NULL;
 158         }
 159         return bh;
 160 }
 161
 162 /*
 163  * NOTE! When we get the inode, we're the only people
 164  * that have access to it, and as such there are no
 165  * race conditions we have to worry about. The inode
 166  * is not on the hash-lists, and it cannot be reached
 167  * through the filesystem because the directory entry
 168  * has been deleted earlier.
 169  *
 170  * HOWEVER: we must make sure that we get no aliases,
 171  * which means that we have to call "clear_inode()"
 172  * _before_ we mark the inode not in use in the inode
 173  * bitmaps. Otherwise a newly created file might use
 174  * the same inode number (not actually the same pointer
 175  * though), and then we'd have two inodes sharing the
 176  * same inode number and space on the harddisk.
 177  */
 178 void ext4_free_inode(handle_t *handle, struct inode *inode)
 179 {
 180         struct super_block *sb = inode->i_sb;
 181         int is_directory;
 182         unsigned long ino;
 183         struct buffer_head *bitmap_bh = NULL;
 184         struct buffer_head *bh2;
 185         ext4_group_t block_group;
 186         unsigned long bit;
 187         struct ext4_group_desc *gdp;
 188         struct ext4_super_block *es;
 189         struct ext4_sb_info *sbi;
 190         int fatal = 0, err, count, cleared;
 191
 192         if (atomic_read(&inode->i_count) > 1) {
 193                 printk(KERN_ERR "ext4_free_inode: inode has count=%d\n",
 194                        atomic_read(&inode->i_count));
 195                 return;
 196         }
 197         if (inode->i_nlink) {
 198                 printk(KERN_ERR "ext4_free_inode: inode has nlink=%d\n",
 199                        inode->i_nlink);
 200                 return;
 201         }
 202         if (!sb) {
 203                 printk(KERN_ERR "ext4_free_inode: inode on "
 204                        "nonexistent device\n");
 205                 return;
 206         }
 207         sbi = EXT4_SB(sb);
 208
 209         ino = inode->i_ino;
 210         ext4_debug("freeing inode %lu\n", ino);
 211         trace_ext4_free_inode(inode);
 212
 213         /*
 214          * Note: we must free any quota before locking the superblock,
 215          * as writing the quota to disk may need the lock as well.
 216          */
 217         dquot_initialize(inode);
 218         ext4_xattr_delete_inode(handle, inode);
 219         dquot_free_inode(inode);
 220         dquot_drop(inode);
 221
 222         is_directory = S_ISDIR(inode->i_mode);
 223
 224         /* Do this BEFORE marking the inode not in use or returning an error */
 225         clear_inode(inode);
 226
 227         es = EXT4_SB(sb)->s_es;
 228         if (ino < EXT4_FIRST_INO(sb) || ino > le32_to_cpu(es->s_inodes_count)) {
 229                 ext4_error(sb, "reserved or nonexistent inode %lu", ino);
 230                 goto error_return;
 231         }
 232         block_group = (ino - 1) / EXT4_INODES_PER_GROUP(sb);
 233         bit = (ino - 1) % EXT4_INODES_PER_GROUP(sb);
 234         bitmap_bh = ext4_read_inode_bitmap(sb, block_group);
 235         if (!bitmap_bh)
 236                 goto error_return;
 237
 238         BUFFER_TRACE(bitmap_bh, "get_write_access");
 239         fatal = ext4_journal_get_write_access(handle, bitmap_bh);
 240         if (fatal)
 241                 goto error_return;
 242
 243         /* Ok, now we can actually update the inode bitmaps.. */
 244         cleared = ext4_clear_bit_atomic(ext4_group_lock_ptr(sb, block_group),
 245                                         bit, bitmap_bh->b_data);
 246         if (!cleared)
 247                 ext4_error(sb, "bit already cleared for inode %lu", ino);
 248         else {
 249                 gdp = ext4_get_group_desc(sb, block_group, &bh2);
 250
 251                 BUFFER_TRACE(bh2, "get_write_access");
 252                 fatal = ext4_journal_get_write_access(handle, bh2);
 253                 if (fatal) goto error_return;
 254
 255                 if (gdp) {
 256                         ext4_lock_group(sb, block_group);
 257                         count = ext4_free_inodes_count(sb, gdp) + 1;
 258                         ext4_free_inodes_set(sb, gdp, count);
 259                         if (is_directory) {
 260                                 count = ext4_used_dirs_count(sb, gdp) - 1;
 261                                 ext4_used_dirs_set(sb, gdp, count);
 262                                 if (sbi->s_log_groups_per_flex) {
 263                                         ext4_group_t f;
 264
 265                                         f = ext4_flex_group(sbi, block_group);
 266                                         atomic_dec(&sbi->s_flex_groups[f].used_dirs);
 267                                 }
 268
 269                         }
 270                         gdp->bg_checksum = ext4_group_desc_csum(sbi,
 271                                                         block_group, gdp);
 272                         ext4_unlock_group(sb, block_group);
 273                         percpu_counter_inc(&sbi->s_freeinodes_counter);
 274                         if (is_directory)
 275                                 percpu_counter_dec(&sbi->s_dirs_counter);
 276
 277                         if (sbi->s_log_groups_per_flex) {
 278                                 ext4_group_t f;
 279
 280                                 f = ext4_flex_group(sbi, block_group);
 281                                 atomic_inc(&sbi->s_flex_groups[f].free_inodes);
 282                         }
 283                 }
 284                 BUFFER_TRACE(bh2, "call ext4_handle_dirty_metadata");
 285                 err = ext4_handle_dirty_metadata(handle, NULL, bh2);
 286                 if (!fatal) fatal = err;
 287         }
 288         BUFFER_TRACE(bitmap_bh, "call ext4_handle_dirty_metadata");
 289         err = ext4_handle_dirty_metadata(handle, NULL, bitmap_bh);
 290         if (!fatal)
 291                 fatal = err;
 292         sb->s_dirt = 1;
 293 error_return:
 294         brelse(bitmap_bh);
 295         ext4_std_error(sb, fatal);
 296 }
 297
 298 /*
 299  * There are two policies for allocating an inode.  If the new inode is
 300  * a directory, then a forward search is made for a block group with both
 301  * free space and a low directory-to-inode ratio; if that fails, then of
 302  * the groups with above-average free space, that group with the fewest
 303  * directories already is chosen.
 304  *
 305  * For other inodes, search forward from the parent directory\'s block
 306  * group to find a free inode.
 307  */
 308 static int find_group_dir(struct super_block *sb, struct inode *parent,
 309                                 ext4_group_t *best_group)
 310 {
 311         ext4_group_t ngroups = ext4_get_groups_count(sb);
 312         unsigned int freei, avefreei;
 313         struct ext4_group_desc *desc, *best_desc = NULL;
 314         ext4_group_t group;
 315         int ret = -1;
 316
 317         freei = percpu_counter_read_positive(&EXT4_SB(sb)->s_freeinodes_counter);
 318         avefreei = freei / ngroups;
 319
 320         for (group = 0; group < ngroups; group++) {
 321                 desc = ext4_get_group_desc(sb, group, NULL);
 322                 if (!desc || !ext4_free_inodes_count(sb, desc))
 323                         continue;
 324                 if (ext4_free_inodes_count(sb, desc) < avefreei)
 325                         continue;
 326                 if (!best_desc ||
 327                     (ext4_free_blks_count(sb, desc) >
 328                      ext4_free_blks_count(sb, best_desc))) {
 329                         *best_group = group;
 330                         best_desc = desc;
 331                         ret = 0;
 332                 }
 333         }
 334         return ret;
 335 }
 336
 337 #define free_block_ratio 10
 338
 339 static int find_group_flex(struct super_block *sb, struct inode *parent,
 340                            ext4_group_t *best_group)
 341 {
 342         struct ext4_sb_info *sbi = EXT4_SB(sb);
 343         struct ext4_group_desc *desc;
 344         struct flex_groups *flex_group = sbi->s_flex_groups;
 345         ext4_group_t parent_group = EXT4_I(parent)->i_block_group;
 346         ext4_group_t parent_fbg_group = ext4_flex_group(sbi, parent_group);
 347         ext4_group_t ngroups = ext4_get_groups_count(sb);
 348         int flex_size = ext4_flex_bg_size(sbi);
 349         ext4_group_t best_flex = parent_fbg_group;
 350         int blocks_per_flex = sbi->s_blocks_per_group * flex_size;
 351         int flexbg_free_blocks;
 352         int flex_freeb_ratio;
 353         ext4_group_t n_fbg_groups;
 354         ext4_group_t i;
 355
 356         n_fbg_groups = (ngroups + flex_size - 1) >>
 357                 sbi->s_log_groups_per_flex;
 358
 359 find_close_to_parent:
 360         flexbg_free_blocks = atomic_read(&flex_group[best_flex].free_blocks);
 361         flex_freeb_ratio = flexbg_free_blocks * 100 / blocks_per_flex;
 362         if (atomic_read(&flex_group[best_flex].free_inodes) &&
 363             flex_freeb_ratio > free_block_ratio)
 364                 goto found_flexbg;
 365
 366         if (best_flex && best_flex == parent_fbg_group) {
 367                 best_flex--;
 368                 goto find_close_to_parent;
 369         }
 370
 371         for (i = 0; i < n_fbg_groups; i++) {
 372                 if (i == parent_fbg_group || i == parent_fbg_group - 1)
 373                         continue;
 374
 375                 flexbg_free_blocks = atomic_read(&flex_group[i].free_blocks);
 376                 flex_freeb_ratio = flexbg_free_blocks * 100 / blocks_per_flex;
 377
 378                 if (flex_freeb_ratio > free_block_ratio &&
 379                     (atomic_read(&flex_group[i].free_inodes))) {
 380                         best_flex = i;
 381                         goto found_flexbg;
 382                 }
 383
 384                 if ((atomic_read(&flex_group[best_flex].free_inodes) == 0) ||
 385                     ((atomic_read(&flex_group[i].free_blocks) >
 386                       atomic_read(&flex_group[best_flex].free_blocks)) &&
 387                      atomic_read(&flex_group[i].free_inodes)))
 388                         best_flex = i;
 389         }
 390
 391         if (!atomic_read(&flex_group[best_flex].free_inodes) ||
 392             !atomic_read(&flex_group[best_flex].free_blocks))
 393                 return -1;
 394
 395 found_flexbg:
 396         for (i = best_flex * flex_size; i < ngroups &&
 397                      i < (best_flex + 1) * flex_size; i++) {
 398                 desc = ext4_get_group_desc(sb, i, NULL);
 399                 if (ext4_free_inodes_count(sb, desc)) {
 400                         *best_group = i;
 401                         goto out;
 402                 }
 403         }
 404
 405         return -1;
 406 out:
 407         return 0;
 408 }
 409
 410 struct orlov_stats {
 411         __u32 free_inodes;
 412         __u32 free_blocks;
 413         __u32 used_dirs;
 414 };
 415
 416 /*
 417  * Helper function for Orlov's allocator; returns critical information
 418  * for a particular block group or flex_bg.  If flex_size is 1, then g
 419  * is a block group number; otherwise it is flex_bg number.
 420  */
 421 void get_orlov_stats(struct super_block *sb, ext4_group_t g,
 422                        int flex_size, struct orlov_stats *stats)
 423 {
 424         struct ext4_group_desc *desc;
 425         struct flex_groups *flex_group = EXT4_SB(sb)->s_flex_groups;
 426
 427         if (flex_size > 1) {
 428                 stats->free_inodes = atomic_read(&flex_group[g].free_inodes);
 429                 stats->free_blocks = atomic_read(&flex_group[g].free_blocks);
 430                 stats->used_dirs = atomic_read(&flex_group[g].used_dirs);
 431                 return;
 432         }
 433
 434         desc = ext4_get_group_desc(sb, g, NULL);
 435         if (desc) {
 436                 stats->free_inodes = ext4_free_inodes_count(sb, desc);
 437                 stats->free_blocks = ext4_free_blks_count(sb, desc);
 438                 stats->used_dirs = ext4_used_dirs_count(sb, desc);
 439         } else {
 440                 stats->free_inodes = 0;
 441                 stats->free_blocks = 0;
 442                 stats->used_dirs = 0;
 443         }
 444 }
 445
 446 /*
 447  * Orlov's allocator for directories.
 448  *
 449  * We always try to spread first-level directories.
 450  *
 451  * If there are blockgroups with both free inodes and free blocks counts
 452  * not worse than average we return one with smallest directory count.
 453  * Otherwise we simply return a random group.
 454  *
 455  * For the rest rules look so:
 456  *
 457  * It's OK to put directory into a group unless
 458  * it has too many directories already (max_dirs) or
 459  * it has too few free inodes left (min_inodes) or
 460  * it has too few free blocks left (min_blocks) or
 461  * Parent's group is preferred, if it doesn't satisfy these
 462  * conditions we search cyclically through the rest. If none
 463  * of the groups look good we just look for a group with more
 464  * free inodes than average (starting at parent's group).
 465  */
 466
 467 static int find_group_orlov(struct super_block *sb, struct inode *parent,
 468                             ext4_group_t *group, int mode,
 469                             const struct qstr *qstr)
 470 {
 471         ext4_group_t parent_group = EXT4_I(parent)->i_block_group;
 472         struct ext4_sb_info *sbi = EXT4_SB(sb);
 473         ext4_group_t real_ngroups = ext4_get_groups_count(sb);
 474         int inodes_per_group = EXT4_INODES_PER_GROUP(sb);
 475         unsigned int freei, avefreei;
 476         ext4_fsblk_t freeb, avefreeb;
 477         unsigned int ndirs;
 478         int max_dirs, min_inodes;
 479         ext4_grpblk_t min_blocks;
 480         ext4_group_t i, grp, g, ngroups;
 481         struct ext4_group_desc *desc;
 482         struct orlov_stats stats;
 483         int flex_size = ext4_flex_bg_size(sbi);
 484         struct dx_hash_info hinfo;
 485
 486         ngroups = real_ngroups;
 487         if (flex_size > 1) {
 488                 ngroups = (real_ngroups + flex_size - 1) >>
 489                         sbi->s_log_groups_per_flex;
 490                 parent_group >>= sbi->s_log_groups_per_flex;
 491         }
 492
 493         freei = percpu_counter_read_positive(&sbi->s_freeinodes_counter);
 494         avefreei = freei / ngroups;
 495         freeb = percpu_counter_read_positive(&sbi->s_freeblocks_counter);
 496         avefreeb = freeb;
 497         do_div(avefreeb, ngroups);
 498         ndirs = percpu_counter_read_positive(&sbi->s_dirs_counter);
 499
 500         if (S_ISDIR(mode) &&
 501             ((parent == sb->s_root->d_inode) ||
 502              (EXT4_I(parent)->i_flags & EXT4_TOPDIR_FL))) {
 503                 int best_ndir = inodes_per_group;
 504                 int ret = -1;
 505
 506                 if (qstr) {
 507                         hinfo.hash_version = DX_HASH_HALF_MD4;
 508                         hinfo.seed = sbi->s_hash_seed;
 509                         ext4fs_dirhash(qstr->name, qstr->len, &hinfo);
 510                         grp = hinfo.hash;
 511                 } else
 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 >= real_ngroups)
 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 = real_ngroups;
 587         avefreei = freei / ngroups;
 588 fallback_retry:
 589         parent_group = EXT4_I(parent)->i_block_group;
 590         for (i = 0; i < ngroups; i++) {
 591                 grp = (parent_group + i) % ngroups;
 592                 desc = ext4_get_group_desc(sb, grp, NULL);
 593                 if (desc && ext4_free_inodes_count(sb, desc) &&
 594                     ext4_free_inodes_count(sb, desc) >= avefreei) {
 595                         *group = grp;
 596                         return 0;
 597                 }
 598         }
 599
 600         if (avefreei) {
 601                 /*
 602                  * The free-inodes counter is approximate, and for really small
 603                  * filesystems the above test can fail to find any blockgroups
 604                  */
 605                 avefreei = 0;
 606                 goto fallback_retry;
 607         }
 608
 609         return -1;
 610 }
 611
 612 static int find_group_other(struct super_block *sb, struct inode *parent,
 613                             ext4_group_t *group, int mode)
 614 {
 615         ext4_group_t parent_group = EXT4_I(parent)->i_block_group;
 616         ext4_group_t i, last, ngroups = ext4_get_groups_count(sb);
 617         struct ext4_group_desc *desc;
 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, 0);
 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 ext4_group_lock
 711  * and clear the uninit flag. The inode bitmap update
 712  * and group desc uninit flag clear should be done
 713  * after holding ext4_group_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         ext4_lock_group(sb, 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                 ext4_unlock_group(sb, group);
 734                 ext4_error(sb, "reserved inode or inode > inodes count - "
 735                            "block_group = %u, inode=%lu", group,
 736                            ino + group * EXT4_INODES_PER_GROUP(sb));
 737                 return 1;
 738         }
 739         /* If we didn't allocate from within the initialized part of the inode
 740          * table then we need to initialize up to this inode. */
 741         if (EXT4_HAS_RO_COMPAT_FEATURE(sb, EXT4_FEATURE_RO_COMPAT_GDT_CSUM)) {
 742
 743                 if (gdp->bg_flags & cpu_to_le16(EXT4_BG_INODE_UNINIT)) {
 744                         gdp->bg_flags &= cpu_to_le16(~EXT4_BG_INODE_UNINIT);
 745                         /* When marking the block group with
 746                          * ~EXT4_BG_INODE_UNINIT we don't want to depend
 747                          * on the value of bg_itable_unused even though
 748                          * mke2fs could have initialized the same for us.
 749                          * Instead we calculated the value below
 750                          */
 751
 752                         free = 0;
 753                 } else {
 754                         free = EXT4_INODES_PER_GROUP(sb) -
 755                                 ext4_itable_unused_count(sb, gdp);
 756                 }
 757
 758                 /*
 759                  * Check the relative inode number against the last used
 760                  * relative inode number in this group. if it is greater
 761                  * we need to  update the bg_itable_unused count
 762                  *
 763                  */
 764                 if (ino > free)
 765                         ext4_itable_unused_set(sb, gdp,
 766                                         (EXT4_INODES_PER_GROUP(sb) - ino));
 767         }
 768         count = ext4_free_inodes_count(sb, gdp) - 1;
 769         ext4_free_inodes_set(sb, gdp, count);
 770         if (S_ISDIR(mode)) {
 771                 count = ext4_used_dirs_count(sb, gdp) + 1;
 772                 ext4_used_dirs_set(sb, gdp, count);
 773                 if (sbi->s_log_groups_per_flex) {
 774                         ext4_group_t f = ext4_flex_group(sbi, group);
 775
 776                         atomic_inc(&sbi->s_flex_groups[f].used_dirs);
 777                 }
 778         }
 779         gdp->bg_checksum = ext4_group_desc_csum(sbi, group, gdp);
 780 err_ret:
 781         ext4_unlock_group(sb, group);
 782         return retval;
 783 }
 784
 785 /*
 786  * There are two policies for allocating an inode.  If the new inode is
 787  * a directory, then a forward search is made for a block group with both
 788  * free space and a low directory-to-inode ratio; if that fails, then of
 789  * the groups with above-average free space, that group with the fewest
 790  * directories already is chosen.
 791  *
 792  * For other inodes, search forward from the parent directory's block
 793  * group to find a free inode.
 794  */
 795 struct inode *ext4_new_inode(handle_t *handle, struct inode *dir, int mode,
 796                              const struct qstr *qstr, __u32 goal)
 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 ngroups, group = 0;
 802         unsigned long ino = 0;
 803         struct inode *inode;
 804         struct ext4_group_desc *gdp = NULL;
 805         struct ext4_inode_info *ei;
 806         struct ext4_sb_info *sbi;
 807         int ret2, err = 0;
 808         struct inode *ret;
 809         ext4_group_t i;
 810         int free = 0;
 811         static int once = 1;
 812         ext4_group_t flex_group;
 813
 814         /* Cannot create files in a deleted directory */
 815         if (!dir || !dir->i_nlink)
 816                 return ERR_PTR(-EPERM);
 817
 818         sb = dir->i_sb;
 819         ngroups = ext4_get_groups_count(sb);
 820         trace_ext4_request_inode(dir, mode);
 821         inode = new_inode(sb);
 822         if (!inode)
 823                 return ERR_PTR(-ENOMEM);
 824         ei = EXT4_I(inode);
 825         sbi = EXT4_SB(sb);
 826
 827         if (!goal)
 828                 goal = sbi->s_inode_goal;
 829
 830         if (goal && goal <= le32_to_cpu(sbi->s_es->s_inodes_count)) {
 831                 group = (goal - 1) / EXT4_INODES_PER_GROUP(sb);
 832                 ino = (goal - 1) % EXT4_INODES_PER_GROUP(sb);
 833                 ret2 = 0;
 834                 goto got_group;
 835         }
 836
 837         if (sbi->s_log_groups_per_flex && test_opt(sb, OLDALLOC)) {
 838                 ret2 = find_group_flex(sb, dir, &group);
 839                 if (ret2 == -1) {
 840                         ret2 = find_group_other(sb, dir, &group, mode);
 841                         if (ret2 == 0 && once) {
 842                                 once = 0;
 843                                 printk(KERN_NOTICE "ext4: find_group_flex "
 844                                        "failed, fallback succeeded dir %lu\n",
 845                                        dir->i_ino);
 846                         }
 847                 }
 848                 goto got_group;
 849         }
 850
 851         if (S_ISDIR(mode)) {
 852                 if (test_opt(sb, OLDALLOC))
 853                         ret2 = find_group_dir(sb, dir, &group);
 854                 else
 855                         ret2 = find_group_orlov(sb, dir, &group, mode, qstr);
 856         } else
 857                 ret2 = find_group_other(sb, dir, &group, mode);
 858
 859 got_group:
 860         EXT4_I(dir)->i_last_alloc_group = group;
 861         err = -ENOSPC;
 862         if (ret2 == -1)
 863                 goto out;
 864
 865         for (i = 0; i < ngroups; i++, ino = 0) {
 866                 err = -EIO;
 867
 868                 gdp = ext4_get_group_desc(sb, group, &group_desc_bh);
 869                 if (!gdp)
 870                         goto fail;
 871
 872                 brelse(inode_bitmap_bh);
 873                 inode_bitmap_bh = ext4_read_inode_bitmap(sb, group);
 874                 if (!inode_bitmap_bh)
 875                         goto fail;
 876
 877 repeat_in_this_group:
 878                 ino = ext4_find_next_zero_bit((unsigned long *)
 879                                               inode_bitmap_bh->b_data,
 880                                               EXT4_INODES_PER_GROUP(sb), ino);
 881
 882                 if (ino < EXT4_INODES_PER_GROUP(sb)) {
 883
 884                         BUFFER_TRACE(inode_bitmap_bh, "get_write_access");
 885                         err = ext4_journal_get_write_access(handle,
 886                                                             inode_bitmap_bh);
 887                         if (err)
 888                                 goto fail;
 889
 890                         BUFFER_TRACE(group_desc_bh, "get_write_access");
 891                         err = ext4_journal_get_write_access(handle,
 892                                                                 group_desc_bh);
 893                         if (err)
 894                                 goto fail;
 895                         if (!ext4_claim_inode(sb, inode_bitmap_bh,
 896                                                 ino, group, mode)) {
 897                                 /* we won it */
 898                                 BUFFER_TRACE(inode_bitmap_bh,
 899                                         "call ext4_handle_dirty_metadata");
 900                                 err = ext4_handle_dirty_metadata(handle,
 901                                                                  NULL,
 902                                                         inode_bitmap_bh);
 903                                 if (err)
 904                                         goto fail;
 905                                 /* zero bit is inode number 1*/
 906                                 ino++;
 907                                 goto got;
 908                         }
 909                         /* we lost it */
 910                         ext4_handle_release_buffer(handle, inode_bitmap_bh);
 911                         ext4_handle_release_buffer(handle, group_desc_bh);
 912
 913                         if (++ino < EXT4_INODES_PER_GROUP(sb))
 914                                 goto repeat_in_this_group;
 915                 }
 916
 917                 /*
 918                  * This case is possible in concurrent environment.  It is very
 919                  * rare.  We cannot repeat the find_group_xxx() call because
 920                  * that will simply return the same blockgroup, because the
 921                  * group descriptor metadata has not yet been updated.
 922                  * So we just go onto the next blockgroup.
 923                  */
 924                 if (++group == ngroups)
 925                         group = 0;
 926         }
 927         err = -ENOSPC;
 928         goto out;
 929
 930 got:
 931         /* We may have to initialize the block bitmap if it isn't already */
 932         if (EXT4_HAS_RO_COMPAT_FEATURE(sb, EXT4_FEATURE_RO_COMPAT_GDT_CSUM) &&
 933             gdp->bg_flags & cpu_to_le16(EXT4_BG_BLOCK_UNINIT)) {
 934                 struct buffer_head *block_bitmap_bh;
 935
 936                 block_bitmap_bh = ext4_read_block_bitmap(sb, group);
 937                 BUFFER_TRACE(block_bitmap_bh, "get block bitmap access");
 938                 err = ext4_journal_get_write_access(handle, block_bitmap_bh);
 939                 if (err) {
 940                         brelse(block_bitmap_bh);
 941                         goto fail;
 942                 }
 943
 944                 free = 0;
 945                 ext4_lock_group(sb, group);
 946                 /* recheck and clear flag under lock if we still need to */
 947                 if (gdp->bg_flags & cpu_to_le16(EXT4_BG_BLOCK_UNINIT)) {
 948                         free = ext4_free_blocks_after_init(sb, group, gdp);
 949                         gdp->bg_flags &= cpu_to_le16(~EXT4_BG_BLOCK_UNINIT);
 950                         ext4_free_blks_set(sb, gdp, free);
 951                         gdp->bg_checksum = ext4_group_desc_csum(sbi, group,
 952                                                                 gdp);
 953                 }
 954                 ext4_unlock_group(sb, group);
 955
 956                 /* Don't need to dirty bitmap block if we didn't change it */
 957                 if (free) {
 958                         BUFFER_TRACE(block_bitmap_bh, "dirty block bitmap");
 959                         err = ext4_handle_dirty_metadata(handle,
 960                                                         NULL, block_bitmap_bh);
 961                 }
 962
 963                 brelse(block_bitmap_bh);
 964                 if (err)
 965                         goto fail;
 966         }
 967         BUFFER_TRACE(group_desc_bh, "call ext4_handle_dirty_metadata");
 968         err = ext4_handle_dirty_metadata(handle, NULL, group_desc_bh);
 969         if (err)
 970                 goto fail;
 971
 972         percpu_counter_dec(&sbi->s_freeinodes_counter);
 973         if (S_ISDIR(mode))
 974                 percpu_counter_inc(&sbi->s_dirs_counter);
 975         sb->s_dirt = 1;
 976
 977         if (sbi->s_log_groups_per_flex) {
 978                 flex_group = ext4_flex_group(sbi, group);
 979                 atomic_dec(&sbi->s_flex_groups[flex_group].free_inodes);
 980         }
 981
 982         inode->i_uid = current_fsuid();
 983         if (test_opt(sb, GRPID))
 984                 inode->i_gid = dir->i_gid;
 985         else if (dir->i_mode & S_ISGID) {
 986                 inode->i_gid = dir->i_gid;
 987                 if (S_ISDIR(mode))
 988                         mode |= S_ISGID;
 989         } else
 990                 inode->i_gid = current_fsgid();
 991         inode->i_mode = mode;
 992
 993         inode->i_ino = ino + group * EXT4_INODES_PER_GROUP(sb);
 994         /* This is the optimal IO size (for stat), not the fs block size */
 995         inode->i_blocks = 0;
 996         inode->i_mtime = inode->i_atime = inode->i_ctime = ei->i_crtime =
 997                                                        ext4_current_time(inode);
 998
 999         memset(ei->i_data, 0, sizeof(ei->i_data));
1000         ei->i_dir_start_lookup = 0;
1001         ei->i_disksize = 0;
1002
1003         /*
1004          * Don't inherit extent flag from directory, amongst others. We set
1005          * extent flag on newly created directory and file only if -o extent
1006          * mount option is specified
1007          */
1008         ei->i_flags =
1009                 ext4_mask_flags(mode, EXT4_I(dir)->i_flags & EXT4_FL_INHERITED);
1010         ei->i_file_acl = 0;
1011         ei->i_dtime = 0;
1012         ei->i_block_group = group;
1013         ei->i_last_alloc_group = ~0;
1014
1015         ext4_set_inode_flags(inode);
1016         if (IS_DIRSYNC(inode))
1017                 ext4_handle_sync(handle);
1018         if (insert_inode_locked(inode) < 0) {
1019                 err = -EINVAL;
1020                 goto fail_drop;
1021         }
1022         spin_lock(&sbi->s_next_gen_lock);
1023         inode->i_generation = sbi->s_next_generation++;
1024         spin_unlock(&sbi->s_next_gen_lock);
1025
1026         ei->i_state_flags = 0;
1027         ext4_set_inode_state(inode, EXT4_STATE_NEW);
1028
1029         ei->i_extra_isize = EXT4_SB(sb)->s_want_extra_isize;
1030
1031         ret = inode;
1032         dquot_initialize(inode);
1033         err = dquot_alloc_inode(inode);
1034         if (err)
1035                 goto fail_drop;
1036
1037         err = ext4_init_acl(handle, inode, dir);
1038         if (err)
1039                 goto fail_free_drop;
1040
1041         err = ext4_init_security(handle, inode, dir);
1042         if (err)
1043                 goto fail_free_drop;
1044
1045         if (EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_EXTENTS)) {
1046                 /* set extent flag only for directory, file and normal symlink*/
1047                 if (S_ISDIR(mode) || S_ISREG(mode) || S_ISLNK(mode)) {
1048                         EXT4_I(inode)->i_flags |= EXT4_EXTENTS_FL;
1049                         ext4_ext_tree_init(handle, inode);
1050                 }
1051         }
1052
1053         err = ext4_mark_inode_dirty(handle, inode);
1054         if (err) {
1055                 ext4_std_error(sb, err);
1056                 goto fail_free_drop;
1057         }
1058
1059         ext4_debug("allocating inode %lu\n", inode->i_ino);
1060         trace_ext4_allocate_inode(inode, dir, mode);
1061         goto really_out;
1062 fail:
1063         ext4_std_error(sb, err);
1064 out:
1065         iput(inode);
1066         ret = ERR_PTR(err);
1067 really_out:
1068         brelse(inode_bitmap_bh);
1069         return ret;
1070
1071 fail_free_drop:
1072         dquot_free_inode(inode);
1073
1074 fail_drop:
1075         dquot_drop(inode);
1076         inode->i_flags |= S_NOQUOTA;
1077         inode->i_nlink = 0;
1078         unlock_new_inode(inode);
1079         iput(inode);
1080         brelse(inode_bitmap_bh);
1081         return ERR_PTR(err);
1082 }
1083
1084 /* Verify that we are loading a valid orphan from disk */
1085 struct inode *ext4_orphan_get(struct super_block *sb, unsigned long ino)
1086 {
1087         unsigned long max_ino = le32_to_cpu(EXT4_SB(sb)->s_es->s_inodes_count);
1088         ext4_group_t block_group;
1089         int bit;
1090         struct buffer_head *bitmap_bh;
1091         struct inode *inode = NULL;
1092         long err = -EIO;
1093
1094         /* Error cases - e2fsck has already cleaned up for us */
1095         if (ino > max_ino) {
1096                 ext4_warning(sb, "bad orphan ino %lu!  e2fsck was run?", ino);
1097                 goto error;
1098         }
1099
1100         block_group = (ino - 1) / EXT4_INODES_PER_GROUP(sb);
1101         bit = (ino - 1) % EXT4_INODES_PER_GROUP(sb);
1102         bitmap_bh = ext4_read_inode_bitmap(sb, block_group);
1103         if (!bitmap_bh) {
1104                 ext4_warning(sb, "inode bitmap error for orphan %lu", ino);
1105                 goto error;
1106         }
1107
1108         /* Having the inode bit set should be a 100% indicator that this
1109          * is a valid orphan (no e2fsck run on fs).  Orphans also include
1110          * inodes that were being truncated, so we can't check i_nlink==0.
1111          */
1112         if (!ext4_test_bit(bit, bitmap_bh->b_data))
1113                 goto bad_orphan;
1114
1115         inode = ext4_iget(sb, ino);
1116         if (IS_ERR(inode))
1117                 goto iget_failed;
1118
1119         /*
1120          * If the orphans has i_nlinks > 0 then it should be able to be
1121          * truncated, otherwise it won't be removed from the orphan list
1122          * during processing and an infinite loop will result.
1123          */
1124         if (inode->i_nlink && !ext4_can_truncate(inode))
1125                 goto bad_orphan;
1126
1127         if (NEXT_ORPHAN(inode) > max_ino)
1128                 goto bad_orphan;
1129         brelse(bitmap_bh);
1130         return inode;
1131
1132 iget_failed:
1133         err = PTR_ERR(inode);
1134         inode = NULL;
1135 bad_orphan:
1136         ext4_warning(sb, "bad orphan inode %lu!  e2fsck was run?", ino);
1137         printk(KERN_NOTICE "ext4_test_bit(bit=%d, block=%llu) = %d\n",
1138                bit, (unsigned long long)bitmap_bh->b_blocknr,
1139                ext4_test_bit(bit, bitmap_bh->b_data));
1140         printk(KERN_NOTICE "inode=%p\n", inode);
1141         if (inode) {
1142                 printk(KERN_NOTICE "is_bad_inode(inode)=%d\n",
1143                        is_bad_inode(inode));
1144                 printk(KERN_NOTICE "NEXT_ORPHAN(inode)=%u\n",
1145                        NEXT_ORPHAN(inode));
1146                 printk(KERN_NOTICE "max_ino=%lu\n", max_ino);
1147                 printk(KERN_NOTICE "i_nlink=%u\n", inode->i_nlink);
1148                 /* Avoid freeing blocks if we got a bad deleted inode */
1149                 if (inode->i_nlink == 0)
1150                         inode->i_blocks = 0;
1151                 iput(inode);
1152         }
1153         brelse(bitmap_bh);
1154 error:
1155         return ERR_PTR(err);
1156 }
1157
1158 unsigned long ext4_count_free_inodes(struct super_block *sb)
1159 {
1160         unsigned long desc_count;
1161         struct ext4_group_desc *gdp;
1162         ext4_group_t i, ngroups = ext4_get_groups_count(sb);
1163 #ifdef EXT4FS_DEBUG
1164         struct ext4_super_block *es;
1165         unsigned long bitmap_count, x;
1166         struct buffer_head *bitmap_bh = NULL;
1167
1168         es = EXT4_SB(sb)->s_es;
1169         desc_count = 0;
1170         bitmap_count = 0;
1171         gdp = NULL;
1172         for (i = 0; i < ngroups; i++) {
1173                 gdp = ext4_get_group_desc(sb, i, NULL);
1174                 if (!gdp)
1175                         continue;
1176                 desc_count += ext4_free_inodes_count(sb, gdp);
1177                 brelse(bitmap_bh);
1178                 bitmap_bh = ext4_read_inode_bitmap(sb, i);
1179                 if (!bitmap_bh)
1180                         continue;
1181
1182                 x = ext4_count_free(bitmap_bh, EXT4_INODES_PER_GROUP(sb) / 8);
1183                 printk(KERN_DEBUG "group %lu: stored = %d, counted = %lu\n",
1184                         (unsigned long) i, ext4_free_inodes_count(sb, gdp), x);
1185                 bitmap_count += x;
1186         }
1187         brelse(bitmap_bh);
1188         printk(KERN_DEBUG "ext4_count_free_inodes: "
1189                "stored = %u, computed = %lu, %lu\n",
1190                le32_to_cpu(es->s_free_inodes_count), desc_count, bitmap_count);
1191         return desc_count;
1192 #else
1193         desc_count = 0;
1194         for (i = 0; i < ngroups; i++) {
1195                 gdp = ext4_get_group_desc(sb, i, NULL);
1196                 if (!gdp)
1197                         continue;
1198                 desc_count += ext4_free_inodes_count(sb, gdp);
1199                 cond_resched();
1200         }
1201         return desc_count;
1202 #endif
1203 }
1204
1205 /* Called at mount-time, super-block is locked */
1206 unsigned long ext4_count_dirs(struct super_block * sb)
1207 {
1208         unsigned long count = 0;
1209         ext4_group_t i, ngroups = ext4_get_groups_count(sb);
1210
1211         for (i = 0; i < ngroups; i++) {
1212                 struct ext4_group_desc *gdp = ext4_get_group_desc(sb, i, NULL);
1213                 if (!gdp)
1214                         continue;
1215                 count += ext4_used_dirs_count(sb, gdp);
1216         }
1217         return count;
1218 }