e2fsck/rehash.c

   1 /*
   2  * rehash.c --- rebuild hash tree directories
   3  *
   4  * Copyright (C) 2002 Theodore Ts'o
   5  *
   6  * %Begin-Header%
   7  * This file may be redistributed under the terms of the GNU Public
   8  * License.
   9  * %End-Header%
  10  *
  11  * This algorithm is designed for simplicity of implementation and to
  12  * pack the directory as much as possible.  It however requires twice
  13  * as much memory as the size of the directory.  The maximum size
  14  * directory supported using a 4k blocksize is roughly a gigabyte, and
  15  * so there may very well be problems with machines that don't have
  16  * virtual memory, and obscenely large directories.
  17  *
  18  * An alternate algorithm which is much more disk intensive could be
  19  * written, and probably will need to be written in the future.  The
  20  * design goals of such an algorithm are: (a) use (roughly) constant
  21  * amounts of memory, no matter how large the directory, (b) the
  22  * directory must be safe at all times, even if e2fsck is interrupted
  23  * in the middle, (c) we must use minimal amounts of extra disk
  24  * blocks.  This pretty much requires an incremental approach, where
  25  * we are reading from one part of the directory, and inserting into
  26  * the front half.  So the algorithm will have to keep track of a
  27  * moving block boundary between the new tree and the old tree, and
  28  * files will need to be moved from the old directory and inserted
  29  * into the new tree.  If the new directory requires space which isn't
  30  * yet available, blocks from the beginning part of the old directory
  31  * may need to be moved to the end of the directory to make room for
  32  * the new tree:
  33  *
  34  *    --------------------------------------------------------
  35  *    |  new tree   |        | old tree                      |
  36  *    --------------------------------------------------------
  37  *                  ^ ptr    ^ptr
  38  *                tail new   head old
  39  *
  40  * This is going to be a pain in the tuckus to implement, and will
  41  * require a lot more disk accesses.  So I'm going to skip it for now;
  42  * it's only really going to be an issue for really, really big
  43  * filesystems (when we reach the level of tens of millions of files
  44  * in a single directory).  It will probably be easier to simply
  45  * require that e2fsck use VM first.
  46  */
  47
  48 #include "config.h"
  49 #include <string.h>
  50 #include <ctype.h>
  51 #include <errno.h>
  52 #include "e2fsck.h"
  53 #include "problem.h"
  54
  55 /* Schedule a dir to be rebuilt during pass 3A. */
  56 void e2fsck_rehash_dir_later(e2fsck_t ctx, ext2_ino_t ino)
  57 {
  58         if (!ctx->dirs_to_hash)
  59                 ext2fs_u32_list_create(&ctx->dirs_to_hash, 50);
  60         if (ctx->dirs_to_hash)
  61                 ext2fs_u32_list_add(ctx->dirs_to_hash, ino);
  62 }
  63
  64 /* Ask if a dir will be rebuilt during pass 3A. */
  65 int e2fsck_dir_will_be_rehashed(e2fsck_t ctx, ext2_ino_t ino)
  66 {
  67         if (ctx->options & E2F_OPT_COMPRESS_DIRS)
  68                 return 1;
  69         if (!ctx->dirs_to_hash)
  70                 return 0;
  71         return ext2fs_u32_list_test(ctx->dirs_to_hash, ino);
  72 }
  73
  74 #undef REHASH_DEBUG
  75
  76 struct fill_dir_struct {
  77         char *buf;
  78         struct ext2_inode *inode;
  79         ext2_ino_t ino;
  80         errcode_t err;
  81         e2fsck_t ctx;
  82         struct hash_entry *harray;
  83         blk_t max_array, num_array;
  84         ext2_off64_t dir_size;
  85         int compress;
  86         ext2_ino_t parent;
  87         ext2_ino_t dir;
  88 };
  89
  90 struct hash_entry {
  91         ext2_dirhash_t  hash;
  92         ext2_dirhash_t  minor_hash;
  93         ino_t           ino;
  94         struct ext2_dir_entry   *dir;
  95 };
  96
  97 struct out_dir {
  98         blk_t           num;
  99         blk_t           max;
 100         char            *buf;
 101         ext2_dirhash_t  *hashes;
 102 };
 103
 104 static int fill_dir_block(ext2_filsys fs,
 105                           blk64_t *block_nr,
 106                           e2_blkcnt_t blockcnt,
 107                           blk64_t ref_block EXT2FS_ATTR((unused)),
 108                           int ref_offset EXT2FS_ATTR((unused)),
 109                           void *priv_data)
 110 {
 111         struct fill_dir_struct  *fd = (struct fill_dir_struct *) priv_data;
 112         struct hash_entry       *new_array, *ent;
 113         struct ext2_dir_entry   *dirent;
 114         char                    *dir;
 115         unsigned int            offset, dir_offset, rec_len, name_len;
 116         int                     hash_alg, hash_flags;
 117
 118         if (blockcnt < 0)
 119                 return 0;
 120
 121         offset = blockcnt * fs->blocksize;
 122         if (offset + fs->blocksize > fd->inode->i_size) {
 123                 fd->err = EXT2_ET_DIR_CORRUPTED;
 124                 return BLOCK_ABORT;
 125         }
 126
 127         dir = (fd->buf+offset);
 128         if (*block_nr == 0) {
 129                 memset(dir, 0, fs->blocksize);
 130                 dirent = (struct ext2_dir_entry *) dir;
 131                 (void) ext2fs_set_rec_len(fs, fs->blocksize, dirent);
 132         } else {
 133                 int flags = fs->flags;
 134                 fs->flags |= EXT2_FLAG_IGNORE_CSUM_ERRORS;
 135                 fd->err = ext2fs_read_dir_block4(fs, *block_nr, dir, 0,
 136                                                  fd->dir);
 137                 fs->flags = (flags & EXT2_FLAG_IGNORE_CSUM_ERRORS) |
 138                             (fs->flags & ~EXT2_FLAG_IGNORE_CSUM_ERRORS);
 139                 if (fd->err)
 140                         return BLOCK_ABORT;
 141         }
 142         hash_flags = fd->inode->i_flags & EXT4_CASEFOLD_FL;
 143         hash_alg = fs->super->s_def_hash_version;
 144         if ((hash_alg <= EXT2_HASH_TEA) &&
 145             (fs->super->s_flags & EXT2_FLAGS_UNSIGNED_HASH))
 146                 hash_alg += 3;
 147         /* While the directory block is "hot", index it. */
 148         dir_offset = 0;
 149         while (dir_offset < fs->blocksize) {
 150                 dirent = (struct ext2_dir_entry *) (dir + dir_offset);
 151                 (void) ext2fs_get_rec_len(fs, dirent, &rec_len);
 152                 name_len = ext2fs_dirent_name_len(dirent);
 153                 if (((dir_offset + rec_len) > fs->blocksize) ||
 154                     (rec_len < 8) ||
 155                     ((rec_len % 4) != 0) ||
 156                     (name_len + 8 > rec_len)) {
 157                         fd->err = EXT2_ET_DIR_CORRUPTED;
 158                         return BLOCK_ABORT;
 159                 }
 160                 dir_offset += rec_len;
 161                 if (dirent->inode == 0)
 162                         continue;
 163                 if ((name_len) == 0) {
 164                         fd->err = EXT2_ET_DIR_CORRUPTED;
 165                         return BLOCK_ABORT;
 166                 }
 167                 if (!fd->compress && (name_len == 1) &&
 168                     (dirent->name[0] == '.'))
 169                         continue;
 170                 if (!fd->compress && (name_len == 2) &&
 171                     (dirent->name[0] == '.') && (dirent->name[1] == '.')) {
 172                         fd->parent = dirent->inode;
 173                         continue;
 174                 }
 175                 if (fd->num_array >= fd->max_array) {
 176                         errcode_t retval;
 177
 178                         retval = ext2fs_resize_array(sizeof(struct hash_entry),
 179                                                      fd->max_array,
 180                                                      fd->max_array + 500,
 181                                                      &fd->harray);
 182                         if (retval) {
 183                                 fd->err = retval;
 184                                 return BLOCK_ABORT;
 185                         }
 186                         fd->max_array += 500;
 187                 }
 188                 ent = fd->harray + fd->num_array++;
 189                 ent->dir = dirent;
 190                 fd->dir_size += EXT2_DIR_REC_LEN(name_len);
 191                 ent->ino = dirent->inode;
 192                 if (fd->compress)
 193                         ent->hash = ent->minor_hash = 0;
 194                 else {
 195                         fd->err = ext2fs_dirhash2(hash_alg,
 196                                                   dirent->name, name_len,
 197                                                   fs->encoding, hash_flags,
 198                                                   fs->super->s_hash_seed,
 199                                                   &ent->hash, &ent->minor_hash);
 200                         if (fd->err)
 201                                 return BLOCK_ABORT;
 202                 }
 203         }
 204
 205         return 0;
 206 }
 207
 208 /* Used for sorting the hash entry */
 209 static EXT2_QSORT_TYPE ino_cmp(const void *a, const void *b)
 210 {
 211         const struct hash_entry *he_a = (const struct hash_entry *) a;
 212         const struct hash_entry *he_b = (const struct hash_entry *) b;
 213
 214         return (he_a->ino - he_b->ino);
 215 }
 216
 217 /* Used for sorting the hash entry */
 218 static EXT2_QSORT_TYPE name_cmp(const void *a, const void *b)
 219 {
 220         const struct hash_entry *he_a = (const struct hash_entry *) a;
 221         const struct hash_entry *he_b = (const struct hash_entry *) b;
 222         unsigned int he_a_len, he_b_len, min_len;
 223         int     ret;
 224
 225         he_a_len = ext2fs_dirent_name_len(he_a->dir);
 226         he_b_len = ext2fs_dirent_name_len(he_b->dir);
 227         min_len = he_a_len;
 228         if (min_len > he_b_len)
 229                 min_len = he_b_len;
 230
 231         ret = memcmp(he_a->dir->name, he_b->dir->name, min_len);
 232         if (ret == 0) {
 233                 if (he_a_len > he_b_len)
 234                         ret = 1;
 235                 else if (he_a_len < he_b_len)
 236                         ret = -1;
 237                 else
 238                         ret = he_b->dir->inode - he_a->dir->inode;
 239         }
 240         return ret;
 241 }
 242
 243 /* Used for sorting the hash entry */
 244 static EXT2_QSORT_TYPE hash_cmp(const void *a, const void *b)
 245 {
 246         const struct hash_entry *he_a = (const struct hash_entry *) a;
 247         const struct hash_entry *he_b = (const struct hash_entry *) b;
 248         int     ret;
 249
 250         if (he_a->hash > he_b->hash)
 251                 ret = 1;
 252         else if (he_a->hash < he_b->hash)
 253                 ret = -1;
 254         else {
 255                 if (he_a->minor_hash > he_b->minor_hash)
 256                         ret = 1;
 257                 else if (he_a->minor_hash < he_b->minor_hash)
 258                         ret = -1;
 259                 else
 260                         ret = name_cmp(a, b);
 261         }
 262         return ret;
 263 }
 264
 265 static errcode_t alloc_size_dir(ext2_filsys fs, struct out_dir *outdir,
 266                                 blk_t blocks)
 267 {
 268         errcode_t retval;
 269
 270         if (outdir->max) {
 271                 retval = ext2fs_resize_array(fs->blocksize, outdir->max, blocks,
 272                                              &outdir->buf);
 273                 if (retval)
 274                         return retval;
 275                 retval = ext2fs_resize_array(sizeof(ext2_dirhash_t),
 276                                              outdir->max, blocks,
 277                                              &outdir->hashes);
 278                 if (retval)
 279                         return retval;
 280         } else {
 281                 retval = ext2fs_get_array(fs->blocksize, blocks, &outdir->buf);
 282                 if (retval)
 283                         return retval;
 284                 retval = ext2fs_get_array(sizeof(ext2_dirhash_t), blocks,
 285                                           &outdir->hashes);
 286                 if (retval)
 287                         return retval;
 288                 outdir->num = 0;
 289         }
 290         outdir->max = blocks;
 291         return 0;
 292 }
 293
 294 static void free_out_dir(struct out_dir *outdir)
 295 {
 296         free(outdir->buf);
 297         free(outdir->hashes);
 298         outdir->max = 0;
 299         outdir->num =0;
 300 }
 301
 302 static errcode_t get_next_block(ext2_filsys fs, struct out_dir *outdir,
 303                          char ** ret)
 304 {
 305         errcode_t       retval;
 306
 307         if (outdir->num >= outdir->max) {
 308                 int increment = outdir->max / 10;
 309
 310                 if (increment < 50)
 311                         increment = 50;
 312                 retval = alloc_size_dir(fs, outdir, outdir->max + increment);
 313                 if (retval)
 314                         return retval;
 315         }
 316         *ret = outdir->buf + (size_t)outdir->num++ * fs->blocksize;
 317         memset(*ret, 0, fs->blocksize);
 318         return 0;
 319 }
 320
 321 /*
 322  * This function is used to make a unique filename.  We do this by
 323  * appending ~0, and then incrementing the number.  However, we cannot
 324  * expand the length of the filename beyond the padding available in
 325  * the directory entry.
 326  */
 327 static void mutate_name(char *str, unsigned int *len)
 328 {
 329         int i;
 330         unsigned int l = *len;
 331
 332         /*
 333          * First check to see if it looks the name has been mutated
 334          * already
 335          */
 336         for (i = l-1; i > 0; i--) {
 337                 if (!isdigit(str[i]))
 338                         break;
 339         }
 340         if ((i == (int)l - 1) || (str[i] != '~')) {
 341                 if (((l-1) & 3) < 2)
 342                         l += 2;
 343                 else
 344                         l = (l+3) & ~3;
 345                 str[l-2] = '~';
 346                 str[l-1] = '0';
 347                 *len = l;
 348                 return;
 349         }
 350         for (i = l-1; i >= 0; i--) {
 351                 if (isdigit(str[i])) {
 352                         if (str[i] == '9')
 353                                 str[i] = '0';
 354                         else {
 355                                 str[i]++;
 356                                 return;
 357                         }
 358                         continue;
 359                 }
 360                 if (i == 1) {
 361                         if (str[0] == 'z')
 362                                 str[0] = 'A';
 363                         else if (str[0] == 'Z') {
 364                                 str[0] = '~';
 365                                 str[1] = '0';
 366                         } else
 367                                 str[0]++;
 368                 } else if (i > 0) {
 369                         str[i] = '1';
 370                         str[i-1] = '~';
 371                 } else {
 372                         if (str[0] == '~')
 373                                 str[0] = 'a';
 374                         else
 375                                 str[0]++;
 376                 }
 377                 break;
 378         }
 379 }
 380
 381 static int duplicate_search_and_fix(e2fsck_t ctx, ext2_filsys fs,
 382                                     ext2_ino_t ino,
 383                                     struct fill_dir_struct *fd)
 384 {
 385         struct problem_context  pctx;
 386         struct hash_entry       *ent, *prev;
 387         blk_t                   i, j;
 388         int                     fixed = 0;
 389         char                    new_name[256];
 390         unsigned int            new_len;
 391         int                     hash_alg;
 392         int hash_flags = fd->inode->i_flags & EXT4_CASEFOLD_FL;
 393
 394         clear_problem_context(&pctx);
 395         pctx.ino = ino;
 396
 397         hash_alg = fs->super->s_def_hash_version;
 398         if ((hash_alg <= EXT2_HASH_TEA) &&
 399             (fs->super->s_flags & EXT2_FLAGS_UNSIGNED_HASH))
 400                 hash_alg += 3;
 401
 402         for (i=1; i < fd->num_array; i++) {
 403                 ent = fd->harray + i;
 404                 prev = ent - 1;
 405                 if (!ent->dir->inode ||
 406                     (ext2fs_dirent_name_len(ent->dir) !=
 407                      ext2fs_dirent_name_len(prev->dir)) ||
 408                     memcmp(ent->dir->name, prev->dir->name,
 409                              ext2fs_dirent_name_len(ent->dir)))
 410                         continue;
 411                 pctx.dirent = ent->dir;
 412                 if ((ent->dir->inode == prev->dir->inode) &&
 413                     fix_problem(ctx, PR_2_DUPLICATE_DIRENT, &pctx)) {
 414                         e2fsck_adjust_inode_count(ctx, ent->dir->inode, -1);
 415                         ent->dir->inode = 0;
 416                         fixed++;
 417                         continue;
 418                 }
 419                 new_len = ext2fs_dirent_name_len(ent->dir);
 420                 if (new_len == 0) {
 421                          /* should never happen */
 422                         ext2fs_unmark_valid(fs);
 423                         continue;
 424                 }
 425                 memcpy(new_name, ent->dir->name, new_len);
 426                 mutate_name(new_name, &new_len);
 427                 for (j=0; j < fd->num_array; j++) {
 428                         if ((i==j) ||
 429                             (new_len !=
 430                              (unsigned) ext2fs_dirent_name_len(fd->harray[j].dir)) ||
 431                             memcmp(new_name, fd->harray[j].dir->name, new_len))
 432                                 continue;
 433                         mutate_name(new_name, &new_len);
 434
 435                         j = -1;
 436                 }
 437                 new_name[new_len] = 0;
 438                 pctx.str = new_name;
 439                 if (fix_problem(ctx, PR_2_NON_UNIQUE_FILE, &pctx)) {
 440                         memcpy(ent->dir->name, new_name, new_len);
 441                         ext2fs_dirent_set_name_len(ent->dir, new_len);
 442                         ext2fs_dirhash2(hash_alg, new_name, new_len,
 443                                         fs->encoding, hash_flags,
 444                                         fs->super->s_hash_seed,
 445                                         &ent->hash, &ent->minor_hash);
 446                         fixed++;
 447                 }
 448         }
 449         return fixed;
 450 }
 451
 452
 453 static errcode_t copy_dir_entries(e2fsck_t ctx,
 454                                   struct fill_dir_struct *fd,
 455                                   struct out_dir *outdir)
 456 {
 457         ext2_filsys             fs = ctx->fs;
 458         errcode_t               retval;
 459         char                    *block_start;
 460         struct hash_entry       *ent;
 461         struct ext2_dir_entry   *dirent;
 462         unsigned int            rec_len, prev_rec_len, left, slack, offset;
 463         int                     i;
 464         ext2_dirhash_t          prev_hash;
 465         int                     csum_size = 0;
 466         struct                  ext2_dir_entry_tail *t;
 467
 468         if (ctx->htree_slack_percentage == 255) {
 469                 profile_get_uint(ctx->profile, "options",
 470                                  "indexed_dir_slack_percentage",
 471                                  0, 20,
 472                                  &ctx->htree_slack_percentage);
 473                 if (ctx->htree_slack_percentage > 100)
 474                         ctx->htree_slack_percentage = 20;
 475         }
 476
 477         if (ext2fs_has_feature_metadata_csum(fs->super))
 478                 csum_size = sizeof(struct ext2_dir_entry_tail);
 479
 480         outdir->max = 0;
 481         retval = alloc_size_dir(fs, outdir,
 482                                 (fd->dir_size / fs->blocksize) + 2);
 483         if (retval)
 484                 return retval;
 485         outdir->num = fd->compress ? 0 : 1;
 486         offset = 0;
 487         outdir->hashes[0] = 0;
 488         prev_hash = 1;
 489         if ((retval = get_next_block(fs, outdir, &block_start)))
 490                 return retval;
 491         dirent = (struct ext2_dir_entry *) block_start;
 492         prev_rec_len = 0;
 493         rec_len = 0;
 494         left = fs->blocksize - csum_size;
 495         slack = fd->compress ? 12 :
 496                 ((fs->blocksize - csum_size) * ctx->htree_slack_percentage)/100;
 497         if (slack < 12)
 498                 slack = 12;
 499         for (i = 0; i < fd->num_array; i++) {
 500                 ent = fd->harray + i;
 501                 if (ent->dir->inode == 0)
 502                         continue;
 503                 rec_len = EXT2_DIR_REC_LEN(ext2fs_dirent_name_len(ent->dir));
 504                 if (rec_len > left) {
 505                         if (left) {
 506                                 left += prev_rec_len;
 507                                 retval = ext2fs_set_rec_len(fs, left, dirent);
 508                                 if (retval)
 509                                         return retval;
 510                         }
 511                         if (csum_size) {
 512                                 t = EXT2_DIRENT_TAIL(block_start,
 513                                                      fs->blocksize);
 514                                 ext2fs_initialize_dirent_tail(fs, t);
 515                         }
 516                         if ((retval = get_next_block(fs, outdir,
 517                                                       &block_start)))
 518                                 return retval;
 519                         offset = 0;
 520                 }
 521                 left = (fs->blocksize - csum_size) - offset;
 522                 dirent = (struct ext2_dir_entry *) (block_start + offset);
 523                 if (offset == 0) {
 524                         if (ent->hash == prev_hash)
 525                                 outdir->hashes[outdir->num-1] = ent->hash | 1;
 526                         else
 527                                 outdir->hashes[outdir->num-1] = ent->hash;
 528                 }
 529                 dirent->inode = ent->dir->inode;
 530                 ext2fs_dirent_set_name_len(dirent,
 531                                            ext2fs_dirent_name_len(ent->dir));
 532                 ext2fs_dirent_set_file_type(dirent,
 533                                             ext2fs_dirent_file_type(ent->dir));
 534                 retval = ext2fs_set_rec_len(fs, rec_len, dirent);
 535                 if (retval)
 536                         return retval;
 537                 prev_rec_len = rec_len;
 538                 memcpy(dirent->name, ent->dir->name,
 539                        ext2fs_dirent_name_len(dirent));
 540                 offset += rec_len;
 541                 left -= rec_len;
 542                 if (left < slack) {
 543                         prev_rec_len += left;
 544                         retval = ext2fs_set_rec_len(fs, prev_rec_len, dirent);
 545                         if (retval)
 546                                 return retval;
 547                         offset += left;
 548                         left = 0;
 549                 }
 550                 prev_hash = ent->hash;
 551         }
 552         if (left)
 553                 retval = ext2fs_set_rec_len(fs, rec_len + left, dirent);
 554         if (csum_size) {
 555                 t = EXT2_DIRENT_TAIL(block_start, fs->blocksize);
 556                 ext2fs_initialize_dirent_tail(fs, t);
 557         }
 558
 559         return retval;
 560 }
 561
 562
 563 static struct ext2_dx_root_info *set_root_node(ext2_filsys fs, char *buf,
 564                                     ext2_ino_t ino, ext2_ino_t parent)
 565 {
 566         struct ext2_dir_entry           *dir;
 567         struct ext2_dx_root_info        *root;
 568         struct ext2_dx_countlimit       *limits;
 569         int                             filetype = 0;
 570         int                             csum_size = 0;
 571
 572         if (ext2fs_has_feature_filetype(fs->super))
 573                 filetype = EXT2_FT_DIR;
 574
 575         memset(buf, 0, fs->blocksize);
 576         dir = (struct ext2_dir_entry *) buf;
 577         dir->inode = ino;
 578         dir->name[0] = '.';
 579         ext2fs_dirent_set_name_len(dir, 1);
 580         ext2fs_dirent_set_file_type(dir, filetype);
 581         dir->rec_len = 12;
 582         dir = (struct ext2_dir_entry *) (buf + 12);
 583         dir->inode = parent;
 584         dir->name[0] = '.';
 585         dir->name[1] = '.';
 586         ext2fs_dirent_set_name_len(dir, 2);
 587         ext2fs_dirent_set_file_type(dir, filetype);
 588         dir->rec_len = fs->blocksize - 12;
 589
 590         root = (struct ext2_dx_root_info *) (buf+24);
 591         root->reserved_zero = 0;
 592         root->hash_version = fs->super->s_def_hash_version;
 593         root->info_length = 8;
 594         root->indirect_levels = 0;
 595         root->unused_flags = 0;
 596
 597         if (ext2fs_has_feature_metadata_csum(fs->super))
 598                 csum_size = sizeof(struct ext2_dx_tail);
 599
 600         limits = (struct ext2_dx_countlimit *) (buf+32);
 601         limits->limit = (fs->blocksize - (32 + csum_size)) /
 602                         sizeof(struct ext2_dx_entry);
 603         limits->count = 0;
 604
 605         return root;
 606 }
 607
 608
 609 static struct ext2_dx_entry *set_int_node(ext2_filsys fs, char *buf)
 610 {
 611         struct ext2_dir_entry           *dir;
 612         struct ext2_dx_countlimit       *limits;
 613         int                             csum_size = 0;
 614
 615         memset(buf, 0, fs->blocksize);
 616         dir = (struct ext2_dir_entry *) buf;
 617         dir->inode = 0;
 618         (void) ext2fs_set_rec_len(fs, fs->blocksize, dir);
 619
 620         if (ext2fs_has_feature_metadata_csum(fs->super))
 621                 csum_size = sizeof(struct ext2_dx_tail);
 622
 623         limits = (struct ext2_dx_countlimit *) (buf+8);
 624         limits->limit = (fs->blocksize - (8 + csum_size)) /
 625                         sizeof(struct ext2_dx_entry);
 626         limits->count = 0;
 627
 628         return (struct ext2_dx_entry *) limits;
 629 }
 630
 631 static int alloc_blocks(ext2_filsys fs,
 632                         struct ext2_dx_countlimit **limit,
 633                         struct ext2_dx_entry **prev_ent,
 634                         struct ext2_dx_entry **next_ent,
 635                         int *prev_offset, int *next_offset,
 636                         struct out_dir *outdir, int i,
 637                         int *prev_count, int *next_count)
 638 {
 639         errcode_t       retval;
 640         char            *block_start;
 641
 642         if (*limit)
 643                 (*limit)->limit = (*limit)->count =
 644                         ext2fs_cpu_to_le16((*limit)->limit);
 645         *prev_ent = (struct ext2_dx_entry *) (outdir->buf + *prev_offset);
 646         (*prev_ent)->block = ext2fs_cpu_to_le32(outdir->num);
 647
 648         if (i != 1)
 649                 (*prev_ent)->hash =
 650                         ext2fs_cpu_to_le32(outdir->hashes[i]);
 651
 652         retval = get_next_block(fs, outdir, &block_start);
 653         if (retval)
 654                 return retval;
 655
 656         /* outdir->buf might be reallocated */
 657         *prev_ent = (struct ext2_dx_entry *) (outdir->buf + *prev_offset);
 658
 659         *next_ent = set_int_node(fs, block_start);
 660         *limit = (struct ext2_dx_countlimit *)(*next_ent);
 661         if (next_offset)
 662                 *next_offset = ((char *) *next_ent - outdir->buf);
 663
 664         *next_count = (*limit)->limit;
 665         (*prev_offset) += sizeof(struct ext2_dx_entry);
 666         (*prev_count)--;
 667
 668         return 0;
 669 }
 670
 671 /*
 672  * This function takes the leaf nodes which have been written in
 673  * outdir, and populates the root node and any necessary interior nodes.
 674  */
 675 static errcode_t calculate_tree(ext2_filsys fs,
 676                                 struct out_dir *outdir,
 677                                 ext2_ino_t ino,
 678                                 ext2_ino_t parent)
 679 {
 680         struct ext2_dx_root_info        *root_info;
 681         struct ext2_dx_entry            *root, *int_ent, *dx_ent = 0;
 682         struct ext2_dx_countlimit       *root_limit, *int_limit, *limit;
 683         errcode_t                       retval;
 684         int                             i, c1, c2, c3, nblks;
 685         int                             limit_offset, int_offset, root_offset;
 686
 687         root_info = set_root_node(fs, outdir->buf, ino, parent);
 688         root_offset = limit_offset = ((char *) root_info - outdir->buf) +
 689                 root_info->info_length;
 690         root_limit = (struct ext2_dx_countlimit *) (outdir->buf + limit_offset);
 691         c1 = root_limit->limit;
 692         nblks = outdir->num;
 693
 694         /* Write out the pointer blocks */
 695         if (nblks - 1 <= c1) {
 696                 /* Just write out the root block, and we're done */
 697                 root = (struct ext2_dx_entry *) (outdir->buf + root_offset);
 698                 for (i=1; i < nblks; i++) {
 699                         root->block = ext2fs_cpu_to_le32(i);
 700                         if (i != 1)
 701                                 root->hash =
 702                                         ext2fs_cpu_to_le32(outdir->hashes[i]);
 703                         root++;
 704                         c1--;
 705                 }
 706         } else if (nblks - 1 <= ext2fs_htree_intnode_maxrecs(fs, c1)) {
 707                 c2 = 0;
 708                 limit = NULL;
 709                 root_info->indirect_levels = 1;
 710                 for (i=1; i < nblks; i++) {
 711                         if (c2 == 0 && c1 == 0)
 712                                 return ENOSPC;
 713                         if (c2 == 0) {
 714                                 retval = alloc_blocks(fs, &limit, &root,
 715                                                       &dx_ent, &root_offset,
 716                                                       NULL, outdir, i, &c1,
 717                                                       &c2);
 718                                 if (retval)
 719                                         return retval;
 720                         }
 721                         dx_ent->block = ext2fs_cpu_to_le32(i);
 722                         if (c2 != limit->limit)
 723                                 dx_ent->hash =
 724                                         ext2fs_cpu_to_le32(outdir->hashes[i]);
 725                         dx_ent++;
 726                         c2--;
 727                 }
 728                 limit->count = ext2fs_cpu_to_le16(limit->limit - c2);
 729                 limit->limit = ext2fs_cpu_to_le16(limit->limit);
 730         } else {
 731                 c2 = 0;
 732                 c3 = 0;
 733                 limit = NULL;
 734                 int_limit = 0;
 735                 root_info->indirect_levels = 2;
 736                 for (i = 1; i < nblks; i++) {
 737                         if (c3 == 0 && c2 == 0 && c1 == 0)
 738                                 return ENOSPC;
 739                         if (c3 == 0 && c2 == 0) {
 740                                 retval = alloc_blocks(fs, &int_limit, &root,
 741                                                       &int_ent, &root_offset,
 742                                                       &int_offset, outdir, i,
 743                                                       &c1, &c2);
 744                                 if (retval)
 745                                         return retval;
 746                         }
 747                         if (c3 == 0) {
 748                                 int delta1 = (char *)int_limit - outdir->buf;
 749                                 int delta2 = (char *)root - outdir->buf;
 750
 751                                 retval = alloc_blocks(fs, &limit, &int_ent,
 752                                                       &dx_ent, &int_offset,
 753                                                       NULL, outdir, i, &c2,
 754                                                       &c3);
 755                                 if (retval)
 756                                         return retval;
 757
 758                                 /* outdir->buf might be reallocated */
 759                                 int_limit = (struct ext2_dx_countlimit *)
 760                                         (outdir->buf + delta1);
 761                                 root = (struct ext2_dx_entry *)
 762                                         (outdir->buf + delta2);
 763                         }
 764                         dx_ent->block = ext2fs_cpu_to_le32(i);
 765                         if (c3 != limit->limit)
 766                                 dx_ent->hash =
 767                                         ext2fs_cpu_to_le32(outdir->hashes[i]);
 768                         dx_ent++;
 769                         c3--;
 770                 }
 771                 int_limit->count = ext2fs_cpu_to_le16(limit->limit - c2);
 772                 int_limit->limit = ext2fs_cpu_to_le16(limit->limit);
 773
 774                 limit->count = ext2fs_cpu_to_le16(limit->limit - c3);
 775                 limit->limit = ext2fs_cpu_to_le16(limit->limit);
 776
 777         }
 778         root_limit = (struct ext2_dx_countlimit *) (outdir->buf + limit_offset);
 779         root_limit->count = ext2fs_cpu_to_le16(root_limit->limit - c1);
 780         root_limit->limit = ext2fs_cpu_to_le16(root_limit->limit);
 781
 782         return 0;
 783 }
 784
 785 struct write_dir_struct {
 786         struct out_dir *outdir;
 787         errcode_t       err;
 788         ext2_ino_t      ino;
 789         e2fsck_t        ctx;
 790         ext2_ino_t      dir;
 791 };
 792
 793 /*
 794  * Helper function which writes out a directory block.
 795  */
 796 static int write_dir_block(ext2_filsys fs,
 797                            blk64_t *block_nr,
 798                            e2_blkcnt_t blockcnt,
 799                            blk64_t ref_block EXT2FS_ATTR((unused)),
 800                            int ref_offset EXT2FS_ATTR((unused)),
 801                            void *priv_data)
 802 {
 803         struct write_dir_struct *wd = (struct write_dir_struct *) priv_data;
 804         char    *dir, *buf = 0;
 805
 806 #ifdef REHASH_DEBUG
 807         printf("%u: write_dir_block %lld:%lld", wd->ino, blockcnt, *block_nr);
 808 #endif
 809         if ((*block_nr == 0) || (blockcnt < 0)) {
 810 #ifdef REHASH_DEBUG
 811                 printf(" - skip\n");
 812 #endif
 813                 return 0;
 814         }
 815         if (blockcnt < wd->outdir->num)
 816                 dir = wd->outdir->buf + (blockcnt * fs->blocksize);
 817         else if (wd->ctx->lost_and_found == wd->dir) {
 818                 /* Don't release any extra directory blocks for lost+found */
 819                 wd->err = ext2fs_new_dir_block(fs, 0, 0, &buf);
 820                 if (wd->err)
 821                         return BLOCK_ABORT;
 822                 dir = buf;
 823                 wd->outdir->num++;
 824         } else {
 825                 /* Don't free blocks at the end of the directory, they
 826                  * will be truncated by the caller. */
 827 #ifdef REHASH_DEBUG
 828                 printf(" - not freed\n");
 829 #endif
 830                 return 0;
 831         }
 832         wd->err = ext2fs_write_dir_block4(fs, *block_nr, dir, 0, wd->dir);
 833         if (buf)
 834                 ext2fs_free_mem(&buf);
 835
 836 #ifdef REHASH_DEBUG
 837         printf(" - write (%d)\n", wd->err);
 838 #endif
 839         if (wd->err)
 840                 return BLOCK_ABORT;
 841         return 0;
 842 }
 843
 844 static errcode_t write_directory(e2fsck_t ctx, ext2_filsys fs,
 845                                  struct out_dir *outdir,
 846                                  ext2_ino_t ino, struct ext2_inode *inode,
 847                                  int compress)
 848 {
 849         struct write_dir_struct wd;
 850         errcode_t       retval;
 851
 852         retval = e2fsck_expand_directory(ctx, ino, -1, outdir->num);
 853         if (retval)
 854                 return retval;
 855
 856         wd.outdir = outdir;
 857         wd.err = 0;
 858         wd.ino = ino;
 859         wd.ctx = ctx;
 860         wd.dir = ino;
 861
 862         retval = ext2fs_block_iterate3(fs, ino, 0, NULL,
 863                                        write_dir_block, &wd);
 864         if (retval)
 865                 return retval;
 866         if (wd.err)
 867                 return wd.err;
 868
 869         e2fsck_read_inode(ctx, ino, inode, "rehash_dir");
 870         if (compress)
 871                 inode->i_flags &= ~EXT2_INDEX_FL;
 872         else
 873                 inode->i_flags |= EXT2_INDEX_FL;
 874 #ifdef REHASH_DEBUG
 875         printf("%u: set inode size to %u blocks = %u bytes\n",
 876                ino, outdir->num, outdir->num * fs->blocksize);
 877 #endif
 878         retval = ext2fs_inode_size_set(fs, inode, (ext2_off64_t)outdir->num *
 879                                                    fs->blocksize);
 880         if (retval)
 881                 return retval;
 882
 883         /* ext2fs_punch() calls ext2fs_write_inode() which writes the size */
 884         return ext2fs_punch(fs, ino, inode, NULL, outdir->num, ~0ULL);
 885 }
 886
 887 errcode_t e2fsck_rehash_dir(e2fsck_t ctx, ext2_ino_t ino,
 888                             struct problem_context *pctx)
 889 {
 890         ext2_filsys             fs = ctx->fs;
 891         errcode_t               retval;
 892         struct ext2_inode       inode;
 893         char                    *dir_buf = 0;
 894         struct fill_dir_struct  fd = { NULL, NULL, 0, 0, 0, NULL,
 895                                        0, 0, 0, 0, 0, 0 };
 896         struct out_dir          outdir = { 0, 0, 0, 0 };
 897
 898         e2fsck_read_inode(ctx, ino, &inode, "rehash_dir");
 899
 900         if (ext2fs_has_feature_inline_data(fs->super) &&
 901            (inode.i_flags & EXT4_INLINE_DATA_FL))
 902                 return 0;
 903
 904         retval = ext2fs_get_mem(inode.i_size, &dir_buf);
 905         if (retval)
 906                 goto errout;
 907
 908         fd.max_array = inode.i_size / 32;
 909         retval = ext2fs_get_array(sizeof(struct hash_entry),
 910                                   fd.max_array, &fd.harray);
 911         if (retval)
 912                 goto errout;
 913
 914         fd.ino = ino;
 915         fd.ctx = ctx;
 916         fd.buf = dir_buf;
 917         fd.inode = &inode;
 918         fd.dir = ino;
 919         if (!ext2fs_has_feature_dir_index(fs->super) ||
 920             (inode.i_size / fs->blocksize) < 2)
 921                 fd.compress = 1;
 922         fd.parent = 0;
 923
 924 retry_nohash:
 925         /* Read in the entire directory into memory */
 926         retval = ext2fs_block_iterate3(fs, ino, 0, 0,
 927                                        fill_dir_block, &fd);
 928         if (fd.err) {
 929                 retval = fd.err;
 930                 goto errout;
 931         }
 932
 933         /*
 934          * If the entries read are less than a block, then don't index
 935          * the directory
 936          */
 937         if (!fd.compress && (fd.dir_size < (fs->blocksize - 24))) {
 938                 fd.compress = 1;
 939                 fd.dir_size = 0;
 940                 fd.num_array = 0;
 941                 goto retry_nohash;
 942         }
 943
 944 #if 0
 945         printf("%d entries (%d bytes) found in inode %d\n",
 946                fd.num_array, fd.dir_size, ino);
 947 #endif
 948
 949         /* Sort the list */
 950 resort:
 951         if (fd.compress && fd.num_array > 1)
 952                 qsort(fd.harray+2, fd.num_array-2, sizeof(struct hash_entry),
 953                       hash_cmp);
 954         else
 955                 qsort(fd.harray, fd.num_array, sizeof(struct hash_entry),
 956                       hash_cmp);
 957
 958         /*
 959          * Look for duplicates
 960          */
 961         if (duplicate_search_and_fix(ctx, fs, ino, &fd))
 962                 goto resort;
 963
 964         if (ctx->options & E2F_OPT_NO) {
 965                 retval = 0;
 966                 goto errout;
 967         }
 968
 969         /* Sort non-hashed directories by inode number */
 970         if (fd.compress && fd.num_array > 1)
 971                 qsort(fd.harray+2, fd.num_array-2,
 972                       sizeof(struct hash_entry), ino_cmp);
 973
 974         /*
 975          * Copy the directory entries.  In a htree directory these
 976          * will become the leaf nodes.
 977          */
 978         retval = copy_dir_entries(ctx, &fd, &outdir);
 979         if (retval)
 980                 goto errout;
 981
 982         free(dir_buf); dir_buf = 0;
 983
 984         if (!fd.compress) {
 985                 /* Calculate the interior nodes */
 986                 retval = calculate_tree(fs, &outdir, ino, fd.parent);
 987                 if (retval)
 988                         goto errout;
 989         }
 990
 991         retval = write_directory(ctx, fs, &outdir, ino, &inode, fd.compress);
 992         if (retval)
 993                 goto errout;
 994
 995         if (ctx->options & E2F_OPT_CONVERT_BMAP)
 996                 retval = e2fsck_rebuild_extents_later(ctx, ino);
 997         else
 998                 retval = e2fsck_check_rebuild_extents(ctx, ino, &inode, pctx);
 999 errout:
1000         ext2fs_free_mem(&dir_buf);
1001         ext2fs_free_mem(&fd.harray);
1002
1003         free_out_dir(&outdir);
1004         return retval;
1005 }
1006
1007 void e2fsck_rehash_directories(e2fsck_t ctx)
1008 {
1009         struct problem_context  pctx;
1010 #ifdef RESOURCE_TRACK
1011         struct resource_track   rtrack;
1012 #endif
1013         struct dir_info         *dir;
1014         ext2_u32_iterate        iter;
1015         struct dir_info_iter *  dirinfo_iter = 0;
1016         ext2_ino_t              ino;
1017         errcode_t               retval;
1018         int                     cur, max, all_dirs, first = 1;
1019
1020         init_resource_track(&rtrack, ctx->fs->io);
1021         all_dirs = ctx->options & E2F_OPT_COMPRESS_DIRS;
1022
1023         if (!ctx->dirs_to_hash && !all_dirs)
1024                 return;
1025
1026         (void) e2fsck_get_lost_and_found(ctx, 0);
1027
1028         clear_problem_context(&pctx);
1029
1030         cur = 0;
1031         if (all_dirs) {
1032                 dirinfo_iter = e2fsck_dir_info_iter_begin(ctx);
1033                 max = e2fsck_get_num_dirinfo(ctx);
1034         } else {
1035                 retval = ext2fs_u32_list_iterate_begin(ctx->dirs_to_hash,
1036                                                        &iter);
1037                 if (retval) {
1038                         pctx.errcode = retval;
1039                         fix_problem(ctx, PR_3A_OPTIMIZE_ITER, &pctx);
1040                         return;
1041                 }
1042                 max = ext2fs_u32_list_count(ctx->dirs_to_hash);
1043         }
1044         while (1) {
1045                 if (all_dirs) {
1046                         if ((dir = e2fsck_dir_info_iter(ctx,
1047                                                         dirinfo_iter)) == 0)
1048                                 break;
1049                         ino = dir->ino;
1050                 } else {
1051                         if (!ext2fs_u32_list_iterate(iter, &ino))
1052                                 break;
1053                 }
1054                 if (!ext2fs_test_inode_bitmap2(ctx->inode_dir_map, ino))
1055                         continue;
1056
1057                 pctx.dir = ino;
1058                 if (first) {
1059                         fix_problem(ctx, PR_3A_PASS_HEADER, &pctx);
1060                         first = 0;
1061                 }
1062 #if 0
1063                 fix_problem(ctx, PR_3A_OPTIMIZE_DIR, &pctx);
1064 #endif
1065                 pctx.errcode = e2fsck_rehash_dir(ctx, ino, &pctx);
1066                 if (pctx.errcode) {
1067                         end_problem_latch(ctx, PR_LATCH_OPTIMIZE_DIR);
1068                         fix_problem(ctx, PR_3A_OPTIMIZE_DIR_ERR, &pctx);
1069                 }
1070                 if (ctx->progress && !ctx->progress_fd)
1071                         e2fsck_simple_progress(ctx, "Rebuilding directory",
1072                                100.0 * (float) (++cur) / (float) max, ino);
1073         }
1074         end_problem_latch(ctx, PR_LATCH_OPTIMIZE_DIR);
1075         if (all_dirs)
1076                 e2fsck_dir_info_iter_end(ctx, dirinfo_iter);
1077         else
1078                 ext2fs_u32_list_iterate_end(iter);
1079
1080         if (ctx->dirs_to_hash)
1081                 ext2fs_u32_list_free(ctx->dirs_to_hash);
1082         ctx->dirs_to_hash = 0;
1083
1084         print_resource_track(ctx, "Pass 3A", &rtrack, ctx->fs->io);
1085 }