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 #include "support/sort_r.h"
  55
  56 /* Schedule a dir to be rebuilt during pass 3A. */
  57 void e2fsck_rehash_dir_later(e2fsck_t ctx, ext2_ino_t ino)
  58 {
  59         if (!ctx->dirs_to_hash)
  60                 ext2fs_u32_list_create(&ctx->dirs_to_hash, 50);
  61         if (ctx->dirs_to_hash)
  62                 ext2fs_u32_list_add(ctx->dirs_to_hash, ino);
  63 }
  64
  65 /* Ask if a dir will be rebuilt during pass 3A. */
  66 int e2fsck_dir_will_be_rehashed(e2fsck_t ctx, ext2_ino_t ino)
  67 {
  68         if (ctx->options & E2F_OPT_COMPRESS_DIRS)
  69                 return 1;
  70         if (!ctx->dirs_to_hash)
  71                 return 0;
  72         return ext2fs_u32_list_test(ctx->dirs_to_hash, ino);
  73 }
  74
  75 #undef REHASH_DEBUG
  76
  77 struct fill_dir_struct {
  78         char *buf;
  79         struct ext2_inode *inode;
  80         ext2_ino_t ino;
  81         errcode_t err;
  82         e2fsck_t ctx;
  83         struct hash_entry *harray;
  84         blk_t max_array, num_array;
  85         ext2_off64_t dir_size;
  86         int compress;
  87         ext2_ino_t parent;
  88         ext2_ino_t dir;
  89         struct ext2_dir_entry *dot_de;
  90         struct ext2_dir_entry *dotdot_de;
  91 };
  92
  93 struct hash_entry {
  94         ext2_dirhash_t  hash;
  95         ext2_dirhash_t  minor_hash;
  96         ino_t           ino;
  97         struct ext2_dir_entry   *dir;
  98 };
  99
 100 struct out_dir {
 101         blk_t           num;
 102         blk_t           max;
 103         char            *buf;
 104         ext2_dirhash_t  *hashes;
 105 };
 106
 107 #define DOTDOT_OFFSET 12
 108
 109 static int is_fake_entry(ext2_filsys fs, int lblk, unsigned int offset)
 110 {
 111         /* Entries in the first block before this value refer to . or .. */
 112         if (lblk == 0 && offset <= DOTDOT_OFFSET)
 113                 return 1;
 114         /* Check if this is likely the csum entry */
 115         if (ext2fs_has_feature_metadata_csum(fs->super) &&
 116             (offset & (fs->blocksize - 1)) ==
 117                             fs->blocksize - sizeof(struct ext2_dir_entry_tail))
 118                 return 1;
 119         return 0;
 120 }
 121
 122 static int fill_dir_block(ext2_filsys fs,
 123                           blk64_t *block_nr,
 124                           e2_blkcnt_t blockcnt,
 125                           blk64_t ref_block EXT2FS_ATTR((unused)),
 126                           int ref_offset EXT2FS_ATTR((unused)),
 127                           void *priv_data)
 128 {
 129         struct fill_dir_struct  *fd = (struct fill_dir_struct *) priv_data;
 130         struct hash_entry       *ent;
 131         struct ext2_dir_entry   *dirent;
 132         char                    *dir;
 133         unsigned int            offset, dir_offset, rec_len, name_len;
 134         int                     hash_alg, hash_flags, hash_in_entry;
 135
 136         if (blockcnt < 0)
 137                 return 0;
 138
 139         offset = blockcnt * fs->blocksize;
 140         if (offset + fs->blocksize > fd->inode->i_size) {
 141                 fd->err = EXT2_ET_DIR_CORRUPTED;
 142                 return BLOCK_ABORT;
 143         }
 144
 145         dir = (fd->buf+offset);
 146         if (*block_nr == 0) {
 147                 memset(dir, 0, fs->blocksize);
 148                 dirent = (struct ext2_dir_entry *) dir;
 149                 (void) ext2fs_set_rec_len(fs, fs->blocksize, dirent);
 150         } else {
 151                 int flags = fs->flags;
 152                 fs->flags |= EXT2_FLAG_IGNORE_CSUM_ERRORS;
 153                 fd->err = ext2fs_read_dir_block4(fs, *block_nr, dir, 0,
 154                                                  fd->dir);
 155                 fs->flags = (flags & EXT2_FLAG_IGNORE_CSUM_ERRORS) |
 156                             (fs->flags & ~EXT2_FLAG_IGNORE_CSUM_ERRORS);
 157                 if (fd->err)
 158                         return BLOCK_ABORT;
 159         }
 160         hash_flags = fd->inode->i_flags & EXT4_CASEFOLD_FL;
 161         hash_in_entry = ext4_hash_in_dirent(fd->inode);
 162         hash_alg = fs->super->s_def_hash_version;
 163         if ((hash_alg <= EXT2_HASH_TEA) &&
 164             (fs->super->s_flags & EXT2_FLAGS_UNSIGNED_HASH))
 165                 hash_alg += 3;
 166         /* While the directory block is "hot", index it. */
 167         dir_offset = 0;
 168         while (dir_offset < fs->blocksize) {
 169                 int min_rec = EXT2_DIR_ENTRY_HEADER_LEN;
 170                 int extended = hash_in_entry && !is_fake_entry(fs, blockcnt, dir_offset);
 171
 172                 if (extended)
 173                         min_rec += EXT2_DIR_ENTRY_HASH_LEN;
 174                 dirent = (struct ext2_dir_entry *) (dir + dir_offset);
 175                 (void) ext2fs_get_rec_len(fs, dirent, &rec_len);
 176                 name_len = ext2fs_dirent_name_len(dirent);
 177                 if (((dir_offset + rec_len) > fs->blocksize) ||
 178                     (rec_len < min_rec) ||
 179                     ((rec_len % 4) != 0) ||
 180                     (name_len + min_rec > rec_len)) {
 181                         fd->err = EXT2_ET_DIR_CORRUPTED;
 182                         return BLOCK_ABORT;
 183                 }
 184                 dir_offset += rec_len;
 185                 if (dirent->inode == 0)
 186                         continue;
 187                 if ((name_len) == 0) {
 188                         fd->err = EXT2_ET_DIR_CORRUPTED;
 189                         return BLOCK_ABORT;
 190                 }
 191                 if (!fd->compress && (name_len == 1) &&
 192                     (dirent->name[0] == '.')) {
 193                         fd->dot_de = dirent;
 194                         continue;
 195                 }
 196                 if (!fd->compress && (name_len == 2) &&
 197                     (dirent->name[0] == '.') && (dirent->name[1] == '.')) {
 198                         fd->parent = dirent->inode;
 199                         fd->dotdot_de = dirent;
 200                         continue;
 201                 }
 202                 if (fd->num_array >= fd->max_array) {
 203                         errcode_t retval;
 204
 205                         retval = ext2fs_resize_array(sizeof(struct hash_entry),
 206                                                      fd->max_array,
 207                                                      fd->max_array + 500,
 208                                                      &fd->harray);
 209                         if (retval) {
 210                                 fd->err = retval;
 211                                 return BLOCK_ABORT;
 212                         }
 213                         fd->max_array += 500;
 214                 }
 215                 ent = fd->harray + fd->num_array++;
 216                 ent->dir = dirent;
 217                 fd->dir_size += ext2fs_dirdata_rec_len(dirent, extended);
 218                 ent->ino = dirent->inode;
 219                 if (extended) {
 220                         ent->hash = EXT2_DIRENT_HASH(dirent);
 221                         ent->minor_hash = EXT2_DIRENT_MINOR_HASH(dirent);
 222                 } else if (fd->compress) {
 223                         ent->hash = ent->minor_hash = 0;
 224                 } else {
 225                         fd->err = ext2fs_dirhash2(hash_alg,
 226                                                   dirent->name, name_len,
 227                                                   fs->encoding, hash_flags,
 228                                                   fs->super->s_hash_seed,
 229                                                   &ent->hash, &ent->minor_hash);
 230                         if (fd->err)
 231                                 return BLOCK_ABORT;
 232                 }
 233         }
 234
 235         return 0;
 236 }
 237
 238 /* Used for sorting the hash entry */
 239 static EXT2_QSORT_TYPE ino_cmp(const void *a, const void *b)
 240 {
 241         const struct hash_entry *he_a = (const struct hash_entry *) a;
 242         const struct hash_entry *he_b = (const struct hash_entry *) b;
 243
 244         return (he_a->ino - he_b->ino);
 245 }
 246
 247 struct name_cmp_ctx
 248 {
 249         int casefold;
 250         const struct ext2fs_nls_table *tbl;
 251 };
 252
 253 static int same_name(const struct name_cmp_ctx *cmp_ctx, char *s1,
 254                      int len1, char *s2, int len2)
 255 {
 256         if (!cmp_ctx->casefold)
 257                 return (len1 == len2 && !memcmp(s1, s2, len1));
 258         else
 259                 return !ext2fs_casefold_cmp(cmp_ctx->tbl,
 260                                             (unsigned char *) s1, len1,
 261                                             (unsigned char *) s2, len2);
 262 }
 263
 264 /* Used for sorting the hash entry */
 265 static EXT2_QSORT_TYPE name_cmp(const void *a, const void *b)
 266 {
 267         const struct hash_entry *he_a = (const struct hash_entry *) a;
 268         const struct hash_entry *he_b = (const struct hash_entry *) b;
 269         unsigned int he_a_len, he_b_len, min_len;
 270         int     ret;
 271
 272         he_a_len = ext2fs_dirent_name_len(he_a->dir);
 273         he_b_len = ext2fs_dirent_name_len(he_b->dir);
 274         min_len = he_a_len;
 275         if (min_len > he_b_len)
 276                 min_len = he_b_len;
 277
 278         ret = memcmp(he_a->dir->name, he_b->dir->name, min_len);
 279         if (ret == 0) {
 280                 if (he_a_len > he_b_len)
 281                         ret = 1;
 282                 else if (he_a_len < he_b_len)
 283                         ret = -1;
 284                 else
 285                         ret = he_b->dir->inode - he_a->dir->inode;
 286         }
 287         return ret;
 288 }
 289
 290 static EXT2_QSORT_TYPE name_cf_cmp(const struct name_cmp_ctx *ctx,
 291                                    const void *a, const void *b)
 292 {
 293         const struct hash_entry *he_a = (const struct hash_entry *) a;
 294         const struct hash_entry *he_b = (const struct hash_entry *) b;
 295         unsigned int he_a_len, he_b_len, min_len;
 296         int ret;
 297
 298         he_a_len = ext2fs_dirent_name_len(he_a->dir);
 299         he_b_len = ext2fs_dirent_name_len(he_b->dir);
 300
 301         ret = ext2fs_casefold_cmp(ctx->tbl,
 302                                   (unsigned char *) he_a->dir->name, he_a_len,
 303                                   (unsigned char *) he_b->dir->name, he_b_len);
 304         if (ret == 0) {
 305                 if (he_a_len > he_b_len)
 306                         ret = 1;
 307                 else if (he_a_len < he_b_len)
 308                         ret = -1;
 309                 else
 310                         ret = he_b->dir->inode - he_a->dir->inode;
 311         }
 312         return ret;
 313 }
 314
 315 /* Used for sorting the hash entry */
 316 static EXT2_QSORT_TYPE hash_cmp(const void *a, const void *b, void *arg)
 317 {
 318         const struct name_cmp_ctx *ctx = (struct name_cmp_ctx *) arg;
 319         const struct hash_entry *he_a = (const struct hash_entry *) a;
 320         const struct hash_entry *he_b = (const struct hash_entry *) b;
 321         int     ret;
 322
 323         if (he_a->hash > he_b->hash)
 324                 ret = 1;
 325         else if (he_a->hash < he_b->hash)
 326                 ret = -1;
 327         else {
 328                 if (he_a->minor_hash > he_b->minor_hash)
 329                         ret = 1;
 330                 else if (he_a->minor_hash < he_b->minor_hash)
 331                         ret = -1;
 332                 else {
 333                         if (ctx->casefold)
 334                                 ret = name_cf_cmp(ctx, a, b);
 335                         else
 336                                 ret = name_cmp(a, b);
 337                 }
 338         }
 339         return ret;
 340 }
 341
 342 static errcode_t alloc_size_dir(ext2_filsys fs, struct out_dir *outdir,
 343                                 blk_t blocks)
 344 {
 345         errcode_t retval;
 346
 347         if (outdir->max) {
 348                 retval = ext2fs_resize_array(fs->blocksize, outdir->max, blocks,
 349                                              &outdir->buf);
 350                 if (retval)
 351                         return retval;
 352                 retval = ext2fs_resize_array(sizeof(ext2_dirhash_t),
 353                                              outdir->max, blocks,
 354                                              &outdir->hashes);
 355                 if (retval)
 356                         return retval;
 357         } else {
 358                 retval = ext2fs_get_array(fs->blocksize, blocks, &outdir->buf);
 359                 if (retval)
 360                         return retval;
 361                 retval = ext2fs_get_array(sizeof(ext2_dirhash_t), blocks,
 362                                           &outdir->hashes);
 363                 if (retval)
 364                         return retval;
 365                 outdir->num = 0;
 366         }
 367         outdir->max = blocks;
 368         return 0;
 369 }
 370
 371 static void free_out_dir(struct out_dir *outdir)
 372 {
 373         free(outdir->buf);
 374         free(outdir->hashes);
 375         outdir->max = 0;
 376         outdir->num =0;
 377 }
 378
 379 static errcode_t get_next_block(ext2_filsys fs, struct out_dir *outdir,
 380                          char ** ret)
 381 {
 382         errcode_t       retval;
 383
 384         if (outdir->num >= outdir->max) {
 385                 int increment = outdir->max / 10;
 386
 387                 if (increment < 50)
 388                         increment = 50;
 389                 retval = alloc_size_dir(fs, outdir, outdir->max + increment);
 390                 if (retval)
 391                         return retval;
 392         }
 393         *ret = outdir->buf + (size_t)outdir->num++ * fs->blocksize;
 394         memset(*ret, 0, fs->blocksize);
 395         return 0;
 396 }
 397
 398 /*
 399  * This function is used to make a unique filename.  We do this by
 400  * appending ~0, and then incrementing the number.  However, we cannot
 401  * expand the length of the filename beyond the padding available in
 402  * the directory entry.
 403  */
 404 static void mutate_name(char *str, unsigned int *len)
 405 {
 406         int i;
 407         unsigned int l = *len;
 408
 409         /*
 410          * First check to see if it looks the name has been mutated
 411          * already
 412          */
 413         for (i = l-1; i > 0; i--) {
 414                 if (!isdigit(str[i]))
 415                         break;
 416         }
 417         if ((i == (int)l - 1) || (str[i] != '~')) {
 418                 if (((l-1) & 3) < 2)
 419                         l += 2;
 420                 else
 421                         l = (l+3) & ~3;
 422                 str[l-2] = '~';
 423                 str[l-1] = '0';
 424                 *len = l;
 425                 return;
 426         }
 427         for (i = l-1; i >= 0; i--) {
 428                 if (isdigit(str[i])) {
 429                         if (str[i] == '9')
 430                                 str[i] = '0';
 431                         else {
 432                                 str[i]++;
 433                                 return;
 434                         }
 435                         continue;
 436                 }
 437                 if (i == 1) {
 438                         if (str[0] == 'z')
 439                                 str[0] = 'A';
 440                         else if (str[0] == 'Z') {
 441                                 str[0] = '~';
 442                                 str[1] = '0';
 443                         } else
 444                                 str[0]++;
 445                 } else if (i > 0) {
 446                         str[i] = '1';
 447                         str[i-1] = '~';
 448                 } else {
 449                         if (str[0] == '~')
 450                                 str[0] = 'a';
 451                         else
 452                                 str[0]++;
 453                 }
 454                 break;
 455         }
 456 }
 457
 458 static int duplicate_search_and_fix(e2fsck_t ctx, ext2_filsys fs,
 459                                     ext2_ino_t ino,
 460                                     struct fill_dir_struct *fd,
 461                                     const struct name_cmp_ctx *cmp_ctx)
 462 {
 463         struct problem_context  pctx;
 464         struct hash_entry       *ent, *prev;
 465         blk_t                   i, j;
 466         int                     fixed = 0;
 467         char                    new_name[256];
 468         unsigned int            new_len;
 469         int                     hash_alg;
 470         int hash_flags = fd->inode->i_flags & EXT4_CASEFOLD_FL;
 471
 472         clear_problem_context(&pctx);
 473         pctx.ino = ino;
 474
 475         hash_alg = fs->super->s_def_hash_version;
 476         if ((hash_alg <= EXT2_HASH_TEA) &&
 477             (fs->super->s_flags & EXT2_FLAGS_UNSIGNED_HASH))
 478                 hash_alg += 3;
 479
 480         for (i=1; i < fd->num_array; i++) {
 481                 ent = fd->harray + i;
 482                 prev = ent - 1;
 483                 if (!ent->dir->inode ||
 484                     !same_name(cmp_ctx, ent->dir->name,
 485                                ext2fs_dirent_name_len(ent->dir),
 486                                prev->dir->name,
 487                                ext2fs_dirent_name_len(prev->dir)))
 488                         continue;
 489                 pctx.dirent = ent->dir;
 490                 if ((ent->dir->inode == prev->dir->inode) &&
 491                     fix_problem(ctx, PR_2_DUPLICATE_DIRENT, &pctx)) {
 492                         e2fsck_adjust_inode_count(ctx, ent->dir->inode, -1);
 493                         ent->dir->inode = 0;
 494                         fixed++;
 495                         continue;
 496                 }
 497                 /* Can't alter encrypted name without key, so just drop it */
 498                 if (fd->inode->i_flags & EXT4_ENCRYPT_FL) {
 499                         if (fix_problem(ctx, PR_2_NON_UNIQUE_FILE_NO_RENAME, &pctx)) {
 500                                 e2fsck_adjust_inode_count(ctx, ent->dir->inode, -1);
 501                                 ent->dir->inode = 0;
 502                                 fixed++;
 503                                 continue;
 504                         }
 505                 }
 506                 new_len = ext2fs_dirent_name_len(ent->dir);
 507                 if (new_len == 0) {
 508                          /* should never happen */
 509                         ext2fs_unmark_valid(fs);
 510                         continue;
 511                 }
 512                 memcpy(new_name, ent->dir->name, new_len);
 513                 mutate_name(new_name, &new_len);
 514                 for (j=0; j < fd->num_array; j++) {
 515                         if ((i==j) ||
 516                             !same_name(cmp_ctx, new_name, new_len,
 517                                        fd->harray[j].dir->name,
 518                                        ext2fs_dirent_name_len(fd->harray[j].dir))) {
 519                                 continue;
 520                         }
 521                         mutate_name(new_name, &new_len);
 522
 523                         j = -1;
 524                 }
 525                 new_name[new_len] = 0;
 526                 pctx.str = new_name;
 527                 if (fix_problem(ctx, PR_2_NON_UNIQUE_FILE, &pctx)) {
 528                         memcpy(ent->dir->name, new_name, new_len);
 529                         ext2fs_dirent_set_name_len(ent->dir, new_len);
 530                         ext2fs_dirhash2(hash_alg, new_name, new_len,
 531                                         fs->encoding, hash_flags,
 532                                         fs->super->s_hash_seed,
 533                                         &ent->hash, &ent->minor_hash);
 534                         fixed++;
 535                 }
 536         }
 537         return fixed;
 538 }
 539
 540
 541 static errcode_t copy_dir_entries(e2fsck_t ctx,
 542                                   struct fill_dir_struct *fd,
 543                                   struct out_dir *outdir)
 544 {
 545         ext2_filsys             fs = ctx->fs;
 546         errcode_t               retval;
 547         char                    *block_start;
 548         struct hash_entry       *ent;
 549         struct ext2_dir_entry   *dirent;
 550         unsigned int            rec_len, prev_rec_len, left, slack, offset;
 551         blk_t                   i;
 552         ext2_dirhash_t          prev_hash;
 553         int                     csum_size = 0;
 554         struct                  ext2_dir_entry_tail *t;
 555         int hash_in_entry = ext4_hash_in_dirent(fd->inode);
 556         int min_rec_len = ext2fs_dir_rec_len(1, hash_in_entry);
 557
 558         if (ctx->htree_slack_percentage == 255) {
 559                 profile_get_uint(ctx->profile, "options",
 560                                  "indexed_dir_slack_percentage",
 561                                  0, 20,
 562                                  &ctx->htree_slack_percentage);
 563                 if (ctx->htree_slack_percentage > 100)
 564                         ctx->htree_slack_percentage = 20;
 565         }
 566
 567         if (ext2fs_has_feature_metadata_csum(fs->super))
 568                 csum_size = sizeof(struct ext2_dir_entry_tail);
 569
 570         outdir->max = 0;
 571         retval = alloc_size_dir(fs, outdir,
 572                                 (fd->dir_size / fs->blocksize) + 2);
 573         if (retval)
 574                 return retval;
 575         outdir->num = fd->compress ? 0 : 1;
 576         offset = 0;
 577         outdir->hashes[0] = 0;
 578         prev_hash = 1;
 579         if ((retval = get_next_block(fs, outdir, &block_start)))
 580                 return retval;
 581         dirent = (struct ext2_dir_entry *) block_start;
 582         prev_rec_len = 0;
 583         rec_len = 0;
 584         left = fs->blocksize - csum_size;
 585         slack = fd->compress ? min_rec_len :
 586                 ((fs->blocksize - csum_size) * ctx->htree_slack_percentage)/100;
 587         if (slack < min_rec_len)
 588                 slack = min_rec_len;
 589         for (i = 0; i < fd->num_array; i++) {
 590                 ent = fd->harray + i;
 591                 if (ent->dir->inode == 0)
 592                         continue;
 593                 rec_len = ext2fs_dirdata_rec_len(ent->dir, hash_in_entry);
 594                 if (rec_len > left) {
 595                         if (left) {
 596                                 left += prev_rec_len;
 597                                 retval = ext2fs_set_rec_len(fs, left, dirent);
 598                                 if (retval)
 599                                         return retval;
 600                         }
 601                         if (csum_size) {
 602                                 t = EXT2_DIRENT_TAIL(block_start,
 603                                                      fs->blocksize);
 604                                 ext2fs_initialize_dirent_tail(fs, t);
 605                         }
 606                         if ((retval = get_next_block(fs, outdir,
 607                                                       &block_start)))
 608                                 return retval;
 609                         offset = 0;
 610                 }
 611                 left = (fs->blocksize - csum_size) - offset;
 612                 dirent = (struct ext2_dir_entry *) (block_start + offset);
 613                 if (offset == 0) {
 614                         if (ent->hash == prev_hash)
 615                                 outdir->hashes[outdir->num-1] = ent->hash | 1;
 616                         else
 617                                 outdir->hashes[outdir->num-1] = ent->hash;
 618                 }
 619                 dirent->inode = ent->dir->inode;
 620                 ext2fs_dirent_set_name_len(dirent,
 621                                            ext2fs_dirent_name_len(ent->dir));
 622                 ext2fs_dirent_set_file_type(dirent,
 623                                             ext2fs_dirent_file_type(ent->dir));
 624                 retval = ext2fs_set_rec_len(fs, rec_len, dirent);
 625                 if (retval)
 626                         return retval;
 627                 prev_rec_len = rec_len;
 628                 memcpy(dirent->name, ent->dir->name, rec_len);
 629                 if (hash_in_entry) {
 630                         EXT2_DIRENT_HASHES(dirent)->hash = ext2fs_cpu_to_le32(ent->hash);
 631                         EXT2_DIRENT_HASHES(dirent)->minor_hash =
 632                                                         ext2fs_cpu_to_le32(ent->minor_hash);
 633                 }
 634                 offset += rec_len;
 635                 left -= rec_len;
 636                 if (left < slack) {
 637                         prev_rec_len += left;
 638                         retval = ext2fs_set_rec_len(fs, prev_rec_len, dirent);
 639                         if (retval)
 640                                 return retval;
 641                         offset += left;
 642                         left = 0;
 643                 }
 644                 prev_hash = ent->hash;
 645         }
 646         if (left)
 647                 retval = ext2fs_set_rec_len(fs, rec_len + left, dirent);
 648         if (csum_size) {
 649                 t = EXT2_DIRENT_TAIL(block_start, fs->blocksize);
 650                 ext2fs_initialize_dirent_tail(fs, t);
 651         }
 652
 653         return retval;
 654 }
 655
 656
 657 static struct ext2_dx_root_info *set_root_node(ext2_filsys fs, char *buf,
 658                                     ext2_ino_t ino, ext2_ino_t parent,
 659                                     struct ext2_dir_entry *dot_de,
 660                                     struct ext2_dir_entry *dotdot_de,
 661                                     struct ext2_inode *inode)
 662 {
 663         struct ext2_dir_entry           *dirent;
 664         struct ext2_dx_root_info        *root;
 665         struct ext2_dx_countlimit       *limits;
 666         int                             csum_size = 0;
 667         int                             offset;
 668         int                             rec_len;
 669
 670         memset(buf, 0, fs->blocksize);
 671         dirent = (struct ext2_dir_entry *) buf;
 672         dirent->inode = ino;
 673
 674         dirent->name_len = dot_de->name_len;
 675         offset = rec_len = dirent->rec_len = dot_de->rec_len;
 676         memcpy(dirent->name, dot_de->name, rec_len);
 677
 678         dirent = EXT2_NEXT_DIRENT(dirent);
 679         /* set to jump over the index block */
 680
 681         dirent->inode = parent;
 682
 683         dirent->name_len = dotdot_de->name_len;
 684         dirent->rec_len = fs->blocksize - rec_len;
 685         rec_len = EXT2_DIR_REC_LEN(dotdot_de);
 686         memcpy(dirent->name, dotdot_de->name, rec_len);
 687         offset += rec_len;
 688
 689         root = (struct ext2_dx_root_info *)(buf + offset);
 690         root->reserved_zero = 0;
 691         if (ext4_hash_in_dirent(inode))
 692                 root->hash_version = EXT2_HASH_SIPHASH;
 693         else
 694                 root->hash_version = fs->super->s_def_hash_version;
 695         root->info_length = sizeof(*root);
 696         root->indirect_levels = 0;
 697         root->unused_flags = 0;
 698         offset += root->info_length;
 699
 700         if (ext2fs_has_feature_metadata_csum(fs->super))
 701                 csum_size = sizeof(struct ext2_dx_tail);
 702
 703         limits = (struct ext2_dx_countlimit *) (buf + offset);
 704         limits->limit = (fs->blocksize - (offset + csum_size)) /
 705                         sizeof(struct ext2_dx_entry);
 706         limits->count = 0;
 707
 708         return root;
 709 }
 710
 711
 712 static struct ext2_dx_entry *set_int_node(ext2_filsys fs, char *buf)
 713 {
 714         struct ext2_dir_entry           *dir;
 715         struct ext2_dx_countlimit       *limits;
 716         int                             csum_size = 0;
 717
 718         memset(buf, 0, fs->blocksize);
 719         dir = (struct ext2_dir_entry *) buf;
 720         dir->inode = 0;
 721         (void) ext2fs_set_rec_len(fs, fs->blocksize, dir);
 722
 723         if (ext2fs_has_feature_metadata_csum(fs->super))
 724                 csum_size = sizeof(struct ext2_dx_tail);
 725
 726         limits = (struct ext2_dx_countlimit *) (buf+8);
 727         limits->limit = (fs->blocksize - (8 + csum_size)) /
 728                         sizeof(struct ext2_dx_entry);
 729         limits->count = 0;
 730
 731         return (struct ext2_dx_entry *) limits;
 732 }
 733
 734 static int alloc_blocks(ext2_filsys fs,
 735                         struct ext2_dx_countlimit **limit,
 736                         struct ext2_dx_entry **prev_ent,
 737                         struct ext2_dx_entry **next_ent,
 738                         int *prev_offset, int *next_offset,
 739                         struct out_dir *outdir, int i,
 740                         int *prev_count, int *next_count)
 741 {
 742         errcode_t       retval;
 743         char            *block_start;
 744
 745         if (*limit)
 746                 (*limit)->limit = (*limit)->count =
 747                         ext2fs_cpu_to_le16((*limit)->limit);
 748         *prev_ent = (struct ext2_dx_entry *) (outdir->buf + *prev_offset);
 749         (*prev_ent)->block = ext2fs_cpu_to_le32(outdir->num);
 750
 751         if (i != 1)
 752                 (*prev_ent)->hash =
 753                         ext2fs_cpu_to_le32(outdir->hashes[i]);
 754
 755         retval = get_next_block(fs, outdir, &block_start);
 756         if (retval)
 757                 return retval;
 758
 759         /* outdir->buf might be reallocated */
 760         *prev_ent = (struct ext2_dx_entry *) (outdir->buf + *prev_offset);
 761
 762         *next_ent = set_int_node(fs, block_start);
 763         *limit = (struct ext2_dx_countlimit *)(*next_ent);
 764         if (next_offset)
 765                 *next_offset = ((char *) *next_ent - outdir->buf);
 766
 767         *next_count = (*limit)->limit;
 768         (*prev_offset) += sizeof(struct ext2_dx_entry);
 769         (*prev_count)--;
 770
 771         return 0;
 772 }
 773
 774 /*
 775  * This function takes the leaf nodes which have been written in
 776  * outdir, and populates the root node and any necessary interior nodes.
 777  */
 778 static errcode_t calculate_tree(ext2_filsys fs,
 779                                 struct out_dir *outdir,
 780                                 ext2_ino_t ino,
 781                                 ext2_ino_t parent,
 782                                 struct ext2_dir_entry *dot_de,
 783                                 struct ext2_dir_entry *dotdot_de,
 784                                 struct ext2_inode *inode)
 785 {
 786         struct ext2_dx_root_info        *root_info;
 787         struct ext2_dx_entry            *root, *int_ent, *dx_ent = 0;
 788         struct ext2_dx_countlimit       *root_limit, *int_limit, *limit;
 789         errcode_t                       retval;
 790         int                             i, c1, c2, c3, nblks;
 791         int                             limit_offset, int_offset, root_offset;
 792
 793         root_info = set_root_node(fs, outdir->buf, ino, parent, dot_de,
 794                                   dotdot_de, inode);
 795
 796         root_offset = limit_offset = ((char *) root_info - outdir->buf) +
 797                 root_info->info_length;
 798         root_limit = (struct ext2_dx_countlimit *) (outdir->buf + limit_offset);
 799         c1 = root_limit->limit;
 800         nblks = outdir->num;
 801
 802         /* Write out the pointer blocks */
 803         if (nblks - 1 <= c1) {
 804                 /* Just write out the root block, and we're done */
 805                 root = (struct ext2_dx_entry *) (outdir->buf + root_offset);
 806                 for (i=1; i < nblks; i++) {
 807                         root->block = ext2fs_cpu_to_le32(i);
 808                         if (i != 1)
 809                                 root->hash =
 810                                         ext2fs_cpu_to_le32(outdir->hashes[i]);
 811                         root++;
 812                         c1--;
 813                 }
 814         } else if (nblks - 1 <= ext2fs_htree_intnode_maxrecs(fs, c1)) {
 815                 c2 = 0;
 816                 limit = NULL;
 817                 root_info->indirect_levels = 1;
 818                 for (i=1; i < nblks; i++) {
 819                         if (c2 == 0 && c1 == 0)
 820                                 return ENOSPC;
 821                         if (c2 == 0) {
 822                                 retval = alloc_blocks(fs, &limit, &root,
 823                                                       &dx_ent, &root_offset,
 824                                                       NULL, outdir, i, &c1,
 825                                                       &c2);
 826                                 if (retval)
 827                                         return retval;
 828                         }
 829                         dx_ent->block = ext2fs_cpu_to_le32(i);
 830                         if (c2 != limit->limit)
 831                                 dx_ent->hash =
 832                                         ext2fs_cpu_to_le32(outdir->hashes[i]);
 833                         dx_ent++;
 834                         c2--;
 835                 }
 836                 limit->count = ext2fs_cpu_to_le16(limit->limit - c2);
 837                 limit->limit = ext2fs_cpu_to_le16(limit->limit);
 838         } else {
 839                 c2 = 0;
 840                 c3 = 0;
 841                 limit = NULL;
 842                 int_limit = 0;
 843                 root_info->indirect_levels = 2;
 844                 for (i = 1; i < nblks; i++) {
 845                         if (c3 == 0 && c2 == 0 && c1 == 0)
 846                                 return ENOSPC;
 847                         if (c3 == 0 && c2 == 0) {
 848                                 retval = alloc_blocks(fs, &int_limit, &root,
 849                                                       &int_ent, &root_offset,
 850                                                       &int_offset, outdir, i,
 851                                                       &c1, &c2);
 852                                 if (retval)
 853                                         return retval;
 854                         }
 855                         if (c3 == 0) {
 856                                 int delta1 = (char *)int_limit - outdir->buf;
 857                                 int delta2 = (char *)root - outdir->buf;
 858
 859                                 retval = alloc_blocks(fs, &limit, &int_ent,
 860                                                       &dx_ent, &int_offset,
 861                                                       NULL, outdir, i, &c2,
 862                                                       &c3);
 863                                 if (retval)
 864                                         return retval;
 865
 866                                 /* outdir->buf might be reallocated */
 867                                 int_limit = (struct ext2_dx_countlimit *)
 868                                         (outdir->buf + delta1);
 869                                 root = (struct ext2_dx_entry *)
 870                                         (outdir->buf + delta2);
 871                         }
 872                         dx_ent->block = ext2fs_cpu_to_le32(i);
 873                         if (c3 != limit->limit)
 874                                 dx_ent->hash =
 875                                         ext2fs_cpu_to_le32(outdir->hashes[i]);
 876                         dx_ent++;
 877                         c3--;
 878                 }
 879                 int_limit->count = ext2fs_cpu_to_le16(limit->limit - c2);
 880                 int_limit->limit = ext2fs_cpu_to_le16(limit->limit);
 881
 882                 limit->count = ext2fs_cpu_to_le16(limit->limit - c3);
 883                 limit->limit = ext2fs_cpu_to_le16(limit->limit);
 884
 885         }
 886         root_limit = (struct ext2_dx_countlimit *) (outdir->buf + limit_offset);
 887         root_limit->count = ext2fs_cpu_to_le16(root_limit->limit - c1);
 888         root_limit->limit = ext2fs_cpu_to_le16(root_limit->limit);
 889
 890         return 0;
 891 }
 892
 893 struct write_dir_struct {
 894         struct out_dir *outdir;
 895         errcode_t       err;
 896         ext2_ino_t      ino;
 897         e2fsck_t        ctx;
 898         ext2_ino_t      dir;
 899 };
 900
 901 /*
 902  * Helper function which writes out a directory block.
 903  */
 904 static int write_dir_block(ext2_filsys fs,
 905                            blk64_t *block_nr,
 906                            e2_blkcnt_t blockcnt,
 907                            blk64_t ref_block EXT2FS_ATTR((unused)),
 908                            int ref_offset EXT2FS_ATTR((unused)),
 909                            void *priv_data)
 910 {
 911         struct write_dir_struct *wd = (struct write_dir_struct *) priv_data;
 912         char    *dir, *buf = 0;
 913
 914 #ifdef REHASH_DEBUG
 915         printf("%u: write_dir_block %lld:%lld", wd->ino, blockcnt, *block_nr);
 916 #endif
 917         if ((*block_nr == 0) || (blockcnt < 0)) {
 918 #ifdef REHASH_DEBUG
 919                 printf(" - skip\n");
 920 #endif
 921                 return 0;
 922         }
 923         if (blockcnt < wd->outdir->num)
 924                 dir = wd->outdir->buf + (blockcnt * fs->blocksize);
 925         else if (wd->ctx->lost_and_found == wd->dir) {
 926                 /* Don't release any extra directory blocks for lost+found */
 927                 wd->err = ext2fs_new_dir_block(fs, 0, 0, &buf);
 928                 if (wd->err)
 929                         return BLOCK_ABORT;
 930                 dir = buf;
 931                 wd->outdir->num++;
 932         } else {
 933                 /* Don't free blocks at the end of the directory, they
 934                  * will be truncated by the caller. */
 935 #ifdef REHASH_DEBUG
 936                 printf(" - not freed\n");
 937 #endif
 938                 return 0;
 939         }
 940         wd->err = ext2fs_write_dir_block4(fs, *block_nr, dir, 0, wd->dir);
 941         if (buf)
 942                 ext2fs_free_mem(&buf);
 943
 944 #ifdef REHASH_DEBUG
 945         printf(" - write (%d)\n", wd->err);
 946 #endif
 947         if (wd->err)
 948                 return BLOCK_ABORT;
 949         return 0;
 950 }
 951
 952 static errcode_t write_directory(e2fsck_t ctx, ext2_filsys fs,
 953                                  struct out_dir *outdir,
 954                                  ext2_ino_t ino, struct ext2_inode *inode,
 955                                  int compress)
 956 {
 957         struct write_dir_struct wd;
 958         errcode_t       retval;
 959
 960         retval = e2fsck_expand_directory(ctx, ino, -1, outdir->num);
 961         if (retval)
 962                 return retval;
 963
 964         wd.outdir = outdir;
 965         wd.err = 0;
 966         wd.ino = ino;
 967         wd.ctx = ctx;
 968         wd.dir = ino;
 969
 970         retval = ext2fs_block_iterate3(fs, ino, 0, NULL,
 971                                        write_dir_block, &wd);
 972         if (retval)
 973                 return retval;
 974         if (wd.err)
 975                 return wd.err;
 976
 977         e2fsck_read_inode(ctx, ino, inode, "rehash_dir");
 978         if (compress)
 979                 inode->i_flags &= ~EXT2_INDEX_FL;
 980         else
 981                 inode->i_flags |= EXT2_INDEX_FL;
 982 #ifdef REHASH_DEBUG
 983         printf("%u: set inode size to %u blocks = %u bytes\n",
 984                ino, outdir->num, outdir->num * fs->blocksize);
 985 #endif
 986         retval = ext2fs_inode_size_set(fs, inode, (ext2_off64_t)outdir->num *
 987                                                    fs->blocksize);
 988         if (retval)
 989                 return retval;
 990
 991         /* ext2fs_punch() calls ext2fs_write_inode() which writes the size */
 992         return ext2fs_punch(fs, ino, inode, NULL, outdir->num, ~0ULL);
 993 }
 994
 995 errcode_t e2fsck_rehash_dir(e2fsck_t ctx, ext2_ino_t ino,
 996                             struct problem_context *pctx)
 997 {
 998         ext2_filsys             fs = ctx->fs;
 999         errcode_t               retval;
1000         struct ext2_inode       inode;
1001         char                    *dir_buf = 0;
1002         struct fill_dir_struct  fd = { NULL, NULL, 0, 0, 0, NULL,
1003                                        0, 0, 0, 0, 0, 0 };
1004         struct out_dir          outdir = { 0, 0, 0, 0 };
1005         struct name_cmp_ctx name_cmp_ctx = {0, NULL};
1006
1007         e2fsck_read_inode(ctx, ino, &inode, "rehash_dir");
1008
1009         if (ext2fs_has_feature_inline_data(fs->super) &&
1010            (inode.i_flags & EXT4_INLINE_DATA_FL))
1011                 return 0;
1012
1013         retval = ext2fs_get_mem(inode.i_size, &dir_buf);
1014         if (retval)
1015                 goto errout;
1016
1017         fd.max_array = inode.i_size / 32;
1018         retval = ext2fs_get_array(sizeof(struct hash_entry),
1019                                   fd.max_array, &fd.harray);
1020         if (retval)
1021                 goto errout;
1022
1023         fd.ino = ino;
1024         fd.ctx = ctx;
1025         fd.buf = dir_buf;
1026         fd.inode = &inode;
1027         fd.dir = ino;
1028         if (!ext2fs_has_feature_dir_index(fs->super) ||
1029             (inode.i_size / fs->blocksize) < 2)
1030                 fd.compress = 1;
1031         fd.parent = 0;
1032
1033         if (fs->encoding && (inode.i_flags & EXT4_CASEFOLD_FL)) {
1034                 name_cmp_ctx.casefold = 1;
1035                 name_cmp_ctx.tbl = fs->encoding;
1036         }
1037
1038 retry_nohash:
1039         /* Read in the entire directory into memory */
1040         retval = ext2fs_block_iterate3(fs, ino, 0, 0,
1041                                        fill_dir_block, &fd);
1042         if (fd.err) {
1043                 retval = fd.err;
1044                 goto errout;
1045         }
1046
1047         /*
1048          * If the entries read are less than a block, then don't index
1049          * the directory
1050          */
1051         if (!fd.compress && (fd.dir_size < (fs->blocksize - 24))) {
1052                 fd.compress = 1;
1053                 fd.dir_size = 0;
1054                 fd.num_array = 0;
1055                 goto retry_nohash;
1056         }
1057
1058 #if 0
1059         printf("%d entries (%d bytes) found in inode %d\n",
1060                fd.num_array, fd.dir_size, ino);
1061 #endif
1062
1063         /* Sort the list */
1064 resort:
1065         if (fd.compress && fd.num_array > 1)
1066                 sort_r_simple(fd.harray+2, fd.num_array-2,
1067                               sizeof(struct hash_entry),
1068                               hash_cmp, &name_cmp_ctx);
1069         else
1070                 sort_r_simple(fd.harray, fd.num_array,
1071                               sizeof(struct hash_entry),
1072                               hash_cmp, &name_cmp_ctx);
1073
1074         /*
1075          * Look for duplicates
1076          */
1077         if (duplicate_search_and_fix(ctx, fs, ino, &fd, &name_cmp_ctx))
1078                 goto resort;
1079
1080         if (ctx->options & E2F_OPT_NO) {
1081                 retval = 0;
1082                 goto errout;
1083         }
1084
1085         /* Sort non-hashed directories by inode number */
1086         if (fd.compress && fd.num_array > 1)
1087                 qsort(fd.harray+2, fd.num_array-2,
1088                       sizeof(struct hash_entry), ino_cmp);
1089
1090         /*
1091          * Copy the directory entries.  In a htree directory these
1092          * will become the leaf nodes.
1093          */
1094         retval = copy_dir_entries(ctx, &fd, &outdir);
1095         if (retval)
1096                 goto errout;
1097
1098         if (!fd.compress) {
1099                 /* Calculate the interior nodes */
1100                 retval = calculate_tree(fs, &outdir, ino, fd.parent,
1101                                         fd.dot_de, fd.dotdot_de, fd.inode);
1102                 if (retval)
1103                         goto errout;
1104         }
1105
1106         retval = write_directory(ctx, fs, &outdir, ino, &inode, fd.compress);
1107         if (retval)
1108                 goto errout;
1109
1110         if (ctx->options & E2F_OPT_CONVERT_BMAP)
1111                 retval = e2fsck_rebuild_extents_later(ctx, ino);
1112         else
1113                 retval = e2fsck_check_rebuild_extents(ctx, ino, &inode, pctx);
1114 errout:
1115         ext2fs_free_mem(&dir_buf);
1116         ext2fs_free_mem(&fd.harray);
1117
1118         free_out_dir(&outdir);
1119         return retval;
1120 }
1121
1122 void e2fsck_rehash_directories(e2fsck_t ctx)
1123 {
1124         struct problem_context  pctx;
1125 #ifdef RESOURCE_TRACK
1126         struct resource_track   rtrack;
1127 #endif
1128         struct dir_info         *dir;
1129         ext2_u32_iterate        iter;
1130         struct dir_info_iter *  dirinfo_iter = 0;
1131         ext2_ino_t              ino;
1132         errcode_t               retval;
1133         int                     cur, max, all_dirs, first = 1;
1134
1135         init_resource_track(&rtrack, ctx->fs->io);
1136         all_dirs = ctx->options & E2F_OPT_COMPRESS_DIRS;
1137
1138         if (!ctx->dirs_to_hash && !all_dirs)
1139                 return;
1140
1141         (void) e2fsck_get_lost_and_found(ctx, 0);
1142
1143         clear_problem_context(&pctx);
1144
1145         cur = 0;
1146         if (all_dirs) {
1147                 dirinfo_iter = e2fsck_dir_info_iter_begin(ctx);
1148                 max = e2fsck_get_num_dirinfo(ctx);
1149         } else {
1150                 retval = ext2fs_u32_list_iterate_begin(ctx->dirs_to_hash,
1151                                                        &iter);
1152                 if (retval) {
1153                         pctx.errcode = retval;
1154                         fix_problem(ctx, PR_3A_OPTIMIZE_ITER, &pctx);
1155                         return;
1156                 }
1157                 max = ext2fs_u32_list_count(ctx->dirs_to_hash);
1158         }
1159         while (1) {
1160                 if (all_dirs) {
1161                         if ((dir = e2fsck_dir_info_iter(ctx,
1162                                                         dirinfo_iter)) == 0)
1163                                 break;
1164                         ino = dir->ino;
1165                 } else {
1166                         if (!ext2fs_u32_list_iterate(iter, &ino))
1167                                 break;
1168                 }
1169                 if (!ext2fs_test_inode_bitmap2(ctx->inode_dir_map, ino))
1170                         continue;
1171
1172                 pctx.dir = ino;
1173                 if (first) {
1174                         fix_problem(ctx, PR_3A_PASS_HEADER, &pctx);
1175                         first = 0;
1176                 }
1177 #if 0
1178                 fix_problem(ctx, PR_3A_OPTIMIZE_DIR, &pctx);
1179 #endif
1180                 pctx.errcode = e2fsck_rehash_dir(ctx, ino, &pctx);
1181                 if (pctx.errcode) {
1182                         end_problem_latch(ctx, PR_LATCH_OPTIMIZE_DIR);
1183                         fix_problem(ctx, PR_3A_OPTIMIZE_DIR_ERR, &pctx);
1184                 }
1185                 if (ctx->progress && !ctx->progress_fd)
1186                         e2fsck_simple_progress(ctx, "Rebuilding directory",
1187                                100.0 * (float) (++cur) / (float) max, ino);
1188         }
1189         end_problem_latch(ctx, PR_LATCH_OPTIMIZE_DIR);
1190         if (all_dirs)
1191                 e2fsck_dir_info_iter_end(ctx, dirinfo_iter);
1192         else
1193                 ext2fs_u32_list_iterate_end(iter);
1194
1195         if (ctx->dirs_to_hash)
1196                 ext2fs_u32_list_free(ctx->dirs_to_hash);
1197         ctx->dirs_to_hash = 0;
1198
1199         print_resource_track(ctx, "Pass 3A", &rtrack, ctx->fs->io);
1200 }