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 <string.h>
  49 #include <ctype.h>
  50 #include <errno.h>
  51 #include "e2fsck.h"
  52 #include "problem.h"
  53
  54 struct fill_dir_struct {
  55         char *buf;
  56         struct ext2_inode *inode;
  57         errcode_t err;
  58         e2fsck_t ctx;
  59         struct hash_entry *harray;
  60         int max_array, num_array;
  61         unsigned int dir_size;
  62         int compress;
  63         ino_t parent;
  64 };
  65
  66 struct hash_entry {
  67         ext2_dirhash_t  hash;
  68         ext2_dirhash_t  minor_hash;
  69         ino_t           ino;
  70         struct ext2_dir_entry   *dir;
  71 };
  72
  73 struct out_dir {
  74         int             num;
  75         int             max;
  76         char            *buf;
  77         ext2_dirhash_t  *hashes;
  78 };
  79
  80 static int fill_dir_block(ext2_filsys fs,
  81                           blk64_t *block_nr,
  82                           e2_blkcnt_t blockcnt,
  83                           blk64_t ref_block EXT2FS_ATTR((unused)),
  84                           int ref_offset EXT2FS_ATTR((unused)),
  85                           void *priv_data)
  86 {
  87         struct fill_dir_struct  *fd = (struct fill_dir_struct *) priv_data;
  88         struct hash_entry       *new_array, *ent;
  89         struct ext2_dir_entry   *dirent;
  90         char                    *dir;
  91         unsigned int            offset, dir_offset, rec_len;
  92         int                     hash_alg;
  93
  94         if (blockcnt < 0)
  95                 return 0;
  96
  97         offset = blockcnt * fs->blocksize;
  98         if (offset + fs->blocksize > fd->inode->i_size) {
  99                 fd->err = EXT2_ET_DIR_CORRUPTED;
 100                 return BLOCK_ABORT;
 101         }
 102         dir = (fd->buf+offset);
 103         if (HOLE_BLKADDR(*block_nr)) {
 104                 memset(dir, 0, fs->blocksize);
 105                 dirent = (struct ext2_dir_entry *) dir;
 106                 (void) ext2fs_set_rec_len(fs, fs->blocksize, dirent);
 107         } else {
 108                 fd->err = ext2fs_read_dir_block3(fs, *block_nr, dir, 0);
 109                 if (fd->err)
 110                         return BLOCK_ABORT;
 111         }
 112         hash_alg = fs->super->s_def_hash_version;
 113         if ((hash_alg <= EXT2_HASH_TEA) &&
 114             (fs->super->s_flags & EXT2_FLAGS_UNSIGNED_HASH))
 115                 hash_alg += 3;
 116         /* While the directory block is "hot", index it. */
 117         dir_offset = 0;
 118         while (dir_offset < fs->blocksize) {
 119                 dirent = (struct ext2_dir_entry *) (dir + dir_offset);
 120                 (void) ext2fs_get_rec_len(fs, dirent, &rec_len);
 121                 if (((dir_offset + rec_len) > fs->blocksize) ||
 122                     (rec_len < 8) ||
 123                     ((rec_len % 4) != 0) ||
 124                     (((dirent->name_len & 0xFF)+8U) > rec_len)) {
 125                         fd->err = EXT2_ET_DIR_CORRUPTED;
 126                         return BLOCK_ABORT;
 127                 }
 128                 dir_offset += rec_len;
 129                 if (dirent->inode == 0)
 130                         continue;
 131                 if (!fd->compress && ((dirent->name_len&0xFF) == 1) &&
 132                     (dirent->name[0] == '.'))
 133                         continue;
 134                 if (!fd->compress && ((dirent->name_len&0xFF) == 2) &&
 135                     (dirent->name[0] == '.') && (dirent->name[1] == '.')) {
 136                         fd->parent = dirent->inode;
 137                         continue;
 138                 }
 139                 if (fd->num_array >= fd->max_array) {
 140                         new_array = realloc(fd->harray,
 141                             sizeof(struct hash_entry) * (fd->max_array+500));
 142                         if (!new_array) {
 143                                 fd->err = ENOMEM;
 144                                 return BLOCK_ABORT;
 145                         }
 146                         fd->harray = new_array;
 147                         fd->max_array += 500;
 148                 }
 149                 ent = fd->harray + fd->num_array++;
 150                 ent->dir = dirent;
 151                 fd->dir_size += EXT2_DIR_REC_LEN(dirent->name_len & 0xFF);
 152                 ent->ino = dirent->inode;
 153                 if (fd->compress)
 154                         ent->hash = ent->minor_hash = 0;
 155                 else {
 156                         fd->err = ext2fs_dirhash(hash_alg, dirent->name,
 157                                                  dirent->name_len & 0xFF,
 158                                                  fs->super->s_hash_seed,
 159                                                  &ent->hash, &ent->minor_hash);
 160                         if (fd->err)
 161                                 return BLOCK_ABORT;
 162                 }
 163         }
 164
 165         return 0;
 166 }
 167
 168 /* Used for sorting the hash entry */
 169 static EXT2_QSORT_TYPE ino_cmp(const void *a, const void *b)
 170 {
 171         const struct hash_entry *he_a = (const struct hash_entry *) a;
 172         const struct hash_entry *he_b = (const struct hash_entry *) b;
 173
 174         return (he_a->ino - he_b->ino);
 175 }
 176
 177 /* Used for sorting the hash entry */
 178 static EXT2_QSORT_TYPE name_cmp(const void *a, const void *b)
 179 {
 180         const struct hash_entry *he_a = (const struct hash_entry *) a;
 181         const struct hash_entry *he_b = (const struct hash_entry *) b;
 182         int     ret;
 183         int     min_len;
 184
 185         min_len = he_a->dir->name_len;
 186         if (min_len > he_b->dir->name_len)
 187                 min_len = he_b->dir->name_len;
 188
 189         ret = strncmp(he_a->dir->name, he_b->dir->name, min_len);
 190         if (ret == 0) {
 191                 if (he_a->dir->name_len > he_b->dir->name_len)
 192                         ret = 1;
 193                 else if (he_a->dir->name_len < he_b->dir->name_len)
 194                         ret = -1;
 195                 else
 196                         ret = he_b->dir->inode - he_a->dir->inode;
 197         }
 198         return ret;
 199 }
 200
 201 /* Used for sorting the hash entry */
 202 static EXT2_QSORT_TYPE hash_cmp(const void *a, const void *b)
 203 {
 204         const struct hash_entry *he_a = (const struct hash_entry *) a;
 205         const struct hash_entry *he_b = (const struct hash_entry *) b;
 206         int     ret;
 207
 208         if (he_a->hash > he_b->hash)
 209                 ret = 1;
 210         else if (he_a->hash < he_b->hash)
 211                 ret = -1;
 212         else {
 213                 if (he_a->minor_hash > he_b->minor_hash)
 214                         ret = 1;
 215                 else if (he_a->minor_hash < he_b->minor_hash)
 216                         ret = -1;
 217                 else
 218                         ret = name_cmp(a, b);
 219         }
 220         return ret;
 221 }
 222
 223 static errcode_t alloc_size_dir(ext2_filsys fs, struct out_dir *outdir,
 224                                 int blocks)
 225 {
 226         void                    *new_mem;
 227
 228         if (outdir->max) {
 229                 new_mem = realloc(outdir->buf, blocks * fs->blocksize);
 230                 if (!new_mem)
 231                         return ENOMEM;
 232                 outdir->buf = new_mem;
 233                 new_mem = realloc(outdir->hashes,
 234                                   blocks * sizeof(ext2_dirhash_t));
 235                 if (!new_mem)
 236                         return ENOMEM;
 237                 outdir->hashes = new_mem;
 238         } else {
 239                 outdir->buf = malloc(blocks * fs->blocksize);
 240                 outdir->hashes = malloc(blocks * sizeof(ext2_dirhash_t));
 241                 outdir->num = 0;
 242         }
 243         outdir->max = blocks;
 244         return 0;
 245 }
 246
 247 static void free_out_dir(struct out_dir *outdir)
 248 {
 249         free(outdir->buf);
 250         free(outdir->hashes);
 251         outdir->max = 0;
 252         outdir->num =0;
 253 }
 254
 255 static errcode_t get_next_block(ext2_filsys fs, struct out_dir *outdir,
 256                          char ** ret)
 257 {
 258         errcode_t       retval;
 259
 260         if (outdir->num >= outdir->max) {
 261                 retval = alloc_size_dir(fs, outdir, outdir->max + 50);
 262                 if (retval)
 263                         return retval;
 264         }
 265         *ret = outdir->buf + (outdir->num++ * fs->blocksize);
 266         memset(*ret, 0, fs->blocksize);
 267         return 0;
 268 }
 269
 270 /*
 271  * This function is used to make a unique filename.  We do this by
 272  * appending ~0, and then incrementing the number.  However, we cannot
 273  * expand the length of the filename beyond the padding available in
 274  * the directory entry.
 275  */
 276 static void mutate_name(char *str, __u16 *len)
 277 {
 278         int     i;
 279         __u16   l = *len & 0xFF, h = *len & 0xff00;
 280
 281         /*
 282          * First check to see if it looks the name has been mutated
 283          * already
 284          */
 285         for (i = l-1; i > 0; i--) {
 286                 if (!isdigit(str[i]))
 287                         break;
 288         }
 289         if ((i == l-1) || (str[i] != '~')) {
 290                 if (((l-1) & 3) < 2)
 291                         l += 2;
 292                 else
 293                         l = (l+3) & ~3;
 294                 str[l-2] = '~';
 295                 str[l-1] = '0';
 296                 *len = l | h;
 297                 return;
 298         }
 299         for (i = l-1; i >= 0; i--) {
 300                 if (isdigit(str[i])) {
 301                         if (str[i] == '9')
 302                                 str[i] = '0';
 303                         else {
 304                                 str[i]++;
 305                                 return;
 306                         }
 307                         continue;
 308                 }
 309                 if (i == 1) {
 310                         if (str[0] == 'z')
 311                                 str[0] = 'A';
 312                         else if (str[0] == 'Z') {
 313                                 str[0] = '~';
 314                                 str[1] = '0';
 315                         } else
 316                                 str[0]++;
 317                 } else if (i > 0) {
 318                         str[i] = '1';
 319                         str[i-1] = '~';
 320                 } else {
 321                         if (str[0] == '~')
 322                                 str[0] = 'a';
 323                         else
 324                                 str[0]++;
 325                 }
 326                 break;
 327         }
 328 }
 329
 330 static int duplicate_search_and_fix(e2fsck_t ctx, ext2_filsys fs,
 331                                     ext2_ino_t ino,
 332                                     struct fill_dir_struct *fd)
 333 {
 334         struct problem_context  pctx;
 335         struct hash_entry       *ent, *prev;
 336         int                     i, j;
 337         int                     fixed = 0;
 338         char                    new_name[256];
 339         __u16                   new_len;
 340         int                     hash_alg;
 341
 342         clear_problem_context(&pctx);
 343         pctx.ino = ino;
 344
 345         hash_alg = fs->super->s_def_hash_version;
 346         if ((hash_alg <= EXT2_HASH_TEA) &&
 347             (fs->super->s_flags & EXT2_FLAGS_UNSIGNED_HASH))
 348                 hash_alg += 3;
 349
 350         for (i=1; i < fd->num_array; i++) {
 351                 ent = fd->harray + i;
 352                 prev = ent - 1;
 353                 if (!ent->dir->inode ||
 354                     ((ent->dir->name_len & 0xFF) !=
 355                      (prev->dir->name_len & 0xFF)) ||
 356                     (strncmp(ent->dir->name, prev->dir->name,
 357                              ent->dir->name_len & 0xFF)))
 358                         continue;
 359                 pctx.dirent = ent->dir;
 360                 if ((ent->dir->inode == prev->dir->inode) &&
 361                     fix_problem(ctx, PR_2_DUPLICATE_DIRENT, &pctx)) {
 362                         e2fsck_adjust_inode_count(ctx, ent->dir->inode, -1);
 363                         ent->dir->inode = 0;
 364                         fixed++;
 365                         continue;
 366                 }
 367                 memcpy(new_name, ent->dir->name, ent->dir->name_len & 0xFF);
 368                 new_len = ent->dir->name_len;
 369                 mutate_name(new_name, &new_len);
 370                 for (j=0; j < fd->num_array; j++) {
 371                         if ((i==j) ||
 372                             ((new_len & 0xFF) !=
 373                              (fd->harray[j].dir->name_len & 0xFF)) ||
 374                             (strncmp(new_name, fd->harray[j].dir->name,
 375                                      new_len & 0xFF)))
 376                                 continue;
 377                         mutate_name(new_name, &new_len);
 378
 379                         j = -1;
 380                 }
 381                 new_name[new_len & 0xFF] = 0;
 382                 pctx.str = new_name;
 383                 if (fix_problem(ctx, PR_2_NON_UNIQUE_FILE, &pctx)) {
 384                         memcpy(ent->dir->name, new_name, new_len & 0xFF);
 385                         ent->dir->name_len = new_len;
 386                         ext2fs_dirhash(hash_alg, ent->dir->name,
 387                                        ent->dir->name_len & 0xFF,
 388                                        fs->super->s_hash_seed,
 389                                        &ent->hash, &ent->minor_hash);
 390                         fixed++;
 391                 }
 392         }
 393         return fixed;
 394 }
 395
 396
 397 static errcode_t copy_dir_entries(e2fsck_t ctx,
 398                                   struct fill_dir_struct *fd,
 399                                   struct out_dir *outdir)
 400 {
 401         ext2_filsys             fs = ctx->fs;
 402         errcode_t               retval;
 403         char                    *block_start;
 404         struct hash_entry       *ent;
 405         struct ext2_dir_entry   *dirent;
 406         unsigned int            rec_len, prev_rec_len, left, slack, offset;
 407         int                     i;
 408         ext2_dirhash_t          prev_hash;
 409
 410         if (ctx->htree_slack_percentage == 255) {
 411                 profile_get_uint(ctx->profile, "options",
 412                                  "indexed_dir_slack_percentage",
 413                                  0, 20,
 414                                  &ctx->htree_slack_percentage);
 415                 if (ctx->htree_slack_percentage > 100)
 416                         ctx->htree_slack_percentage = 20;
 417         }
 418
 419         outdir->max = 0;
 420         retval = alloc_size_dir(fs, outdir,
 421                                 (fd->dir_size / fs->blocksize) + 2);
 422         if (retval)
 423                 return retval;
 424         outdir->num = fd->compress ? 0 : 1;
 425         offset = 0;
 426         outdir->hashes[0] = 0;
 427         prev_hash = 1;
 428         if ((retval = get_next_block(fs, outdir, &block_start)))
 429                 return retval;
 430         dirent = (struct ext2_dir_entry *) block_start;
 431         prev_rec_len = 0;
 432         rec_len = 0;
 433         left = fs->blocksize;
 434         slack = fd->compress ? 12 :
 435                 (fs->blocksize * ctx->htree_slack_percentage)/100;
 436         if (slack < 12)
 437                 slack = 12;
 438         for (i = 0; i < fd->num_array; i++) {
 439                 ent = fd->harray + i;
 440                 if (ent->dir->inode == 0)
 441                         continue;
 442                 rec_len = EXT2_DIR_REC_LEN(ent->dir->name_len & 0xFF);
 443                 if (rec_len > left) {
 444                         if (left) {
 445                                 left += prev_rec_len;
 446                                 retval = ext2fs_set_rec_len(fs, left, dirent);
 447                                 if (retval)
 448                                         return retval;
 449                         }
 450                         if ((retval = get_next_block(fs, outdir,
 451                                                       &block_start)))
 452                                 return retval;
 453                         offset = 0;
 454                 }
 455                 left = fs->blocksize - offset;
 456                 dirent = (struct ext2_dir_entry *) (block_start + offset);
 457                 if (offset == 0) {
 458                         if (ent->hash == prev_hash)
 459                                 outdir->hashes[outdir->num-1] = ent->hash | 1;
 460                         else
 461                                 outdir->hashes[outdir->num-1] = ent->hash;
 462                 }
 463                 dirent->inode = ent->dir->inode;
 464                 dirent->name_len = ent->dir->name_len;
 465                 retval = ext2fs_set_rec_len(fs, rec_len, dirent);
 466                 if (retval)
 467                         return retval;
 468                 prev_rec_len = rec_len;
 469                 memcpy(dirent->name, ent->dir->name, dirent->name_len & 0xFF);
 470                 offset += rec_len;
 471                 left -= rec_len;
 472                 if (left < slack) {
 473                         prev_rec_len += left;
 474                         retval = ext2fs_set_rec_len(fs, prev_rec_len, dirent);
 475                         if (retval)
 476                                 return retval;
 477                         offset += left;
 478                         left = 0;
 479                 }
 480                 prev_hash = ent->hash;
 481         }
 482         if (left)
 483                 retval = ext2fs_set_rec_len(fs, rec_len + left, dirent);
 484
 485         return retval;
 486 }
 487
 488
 489 static struct ext2_dx_root_info *set_root_node(ext2_filsys fs, char *buf,
 490                                     ext2_ino_t ino, ext2_ino_t parent)
 491 {
 492         struct ext2_dir_entry           *dir;
 493         struct ext2_dx_root_info        *root;
 494         struct ext2_dx_countlimit       *limits;
 495         int                             filetype = 0;
 496
 497         if (fs->super->s_feature_incompat & EXT2_FEATURE_INCOMPAT_FILETYPE)
 498                 filetype = EXT2_FT_DIR << 8;
 499
 500         memset(buf, 0, fs->blocksize);
 501         dir = (struct ext2_dir_entry *) buf;
 502         dir->inode = ino;
 503         dir->name[0] = '.';
 504         dir->name_len = 1 | filetype;
 505         dir->rec_len = 12;
 506         dir = (struct ext2_dir_entry *) (buf + 12);
 507         dir->inode = parent;
 508         dir->name[0] = '.';
 509         dir->name[1] = '.';
 510         dir->name_len = 2 | filetype;
 511         dir->rec_len = fs->blocksize - 12;
 512
 513         root = (struct ext2_dx_root_info *) (buf+24);
 514         root->reserved_zero = 0;
 515         root->hash_version = fs->super->s_def_hash_version;
 516         root->info_length = 8;
 517         root->indirect_levels = 0;
 518         root->unused_flags = 0;
 519
 520         limits = (struct ext2_dx_countlimit *) (buf+32);
 521         limits->limit = (fs->blocksize - 32) / sizeof(struct ext2_dx_entry);
 522         limits->count = 0;
 523
 524         return root;
 525 }
 526
 527
 528 static struct ext2_dx_entry *set_int_node(ext2_filsys fs, char *buf)
 529 {
 530         struct ext2_dir_entry           *dir;
 531         struct ext2_dx_countlimit       *limits;
 532
 533         memset(buf, 0, fs->blocksize);
 534         dir = (struct ext2_dir_entry *) buf;
 535         dir->inode = 0;
 536         (void) ext2fs_set_rec_len(fs, fs->blocksize, dir);
 537
 538         limits = (struct ext2_dx_countlimit *) (buf+8);
 539         limits->limit = (fs->blocksize - 8) / sizeof(struct ext2_dx_entry);
 540         limits->count = 0;
 541
 542         return (struct ext2_dx_entry *) limits;
 543 }
 544
 545 /*
 546  * This function takes the leaf nodes which have been written in
 547  * outdir, and populates the root node and any necessary interior nodes.
 548  */
 549 static errcode_t calculate_tree(ext2_filsys fs,
 550                                 struct out_dir *outdir,
 551                                 ext2_ino_t ino,
 552                                 ext2_ino_t parent)
 553 {
 554         struct ext2_dx_root_info        *root_info;
 555         struct ext2_dx_entry            *root, *dx_ent = 0;
 556         struct ext2_dx_countlimit       *root_limit, *limit;
 557         errcode_t                       retval;
 558         char                            * block_start;
 559         int                             i, c1, c2, nblks;
 560         int                             limit_offset, root_offset;
 561
 562         root_info = set_root_node(fs, outdir->buf, ino, parent);
 563         root_offset = limit_offset = ((char *) root_info - outdir->buf) +
 564                 root_info->info_length;
 565         root_limit = (struct ext2_dx_countlimit *) (outdir->buf + limit_offset);
 566         c1 = root_limit->limit;
 567         nblks = outdir->num;
 568
 569         /* Write out the pointer blocks */
 570         if (nblks-1 <= c1) {
 571                 /* Just write out the root block, and we're done */
 572                 root = (struct ext2_dx_entry *) (outdir->buf + root_offset);
 573                 for (i=1; i < nblks; i++) {
 574                         root->block = ext2fs_cpu_to_le32(i);
 575                         if (i != 1)
 576                                 root->hash =
 577                                         ext2fs_cpu_to_le32(outdir->hashes[i]);
 578                         root++;
 579                         c1--;
 580                 }
 581         } else {
 582                 c2 = 0;
 583                 limit = 0;
 584                 root_info->indirect_levels = 1;
 585                 for (i=1; i < nblks; i++) {
 586                         if (c1 == 0)
 587                                 return ENOSPC;
 588                         if (c2 == 0) {
 589                                 if (limit)
 590                                         limit->limit = limit->count =
 591                 ext2fs_cpu_to_le16(limit->limit);
 592                                 root = (struct ext2_dx_entry *)
 593                                         (outdir->buf + root_offset);
 594                                 root->block = ext2fs_cpu_to_le32(outdir->num);
 595                                 if (i != 1)
 596                                         root->hash =
 597                         ext2fs_cpu_to_le32(outdir->hashes[i]);
 598                                 if ((retval =  get_next_block(fs, outdir,
 599                                                               &block_start)))
 600                                         return retval;
 601                                 dx_ent = set_int_node(fs, block_start);
 602                                 limit = (struct ext2_dx_countlimit *) dx_ent;
 603                                 c2 = limit->limit;
 604                                 root_offset += sizeof(struct ext2_dx_entry);
 605                                 c1--;
 606                         }
 607                         dx_ent->block = ext2fs_cpu_to_le32(i);
 608                         if (c2 != limit->limit)
 609                                 dx_ent->hash =
 610                                         ext2fs_cpu_to_le32(outdir->hashes[i]);
 611                         dx_ent++;
 612                         c2--;
 613                 }
 614                 limit->count = ext2fs_cpu_to_le16(limit->limit - c2);
 615                 limit->limit = ext2fs_cpu_to_le16(limit->limit);
 616         }
 617         root_limit = (struct ext2_dx_countlimit *) (outdir->buf + limit_offset);
 618         root_limit->count = ext2fs_cpu_to_le16(root_limit->limit - c1);
 619         root_limit->limit = ext2fs_cpu_to_le16(root_limit->limit);
 620
 621         return 0;
 622 }
 623
 624 struct write_dir_struct {
 625         struct out_dir *outdir;
 626         errcode_t       err;
 627         e2fsck_t        ctx;
 628         blk64_t         cleared;
 629 };
 630
 631 /*
 632  * Helper function which writes out a directory block.
 633  */
 634 static int write_dir_block(ext2_filsys fs,
 635                            blk64_t *block_nr,
 636                            e2_blkcnt_t blockcnt,
 637                            blk64_t ref_block EXT2FS_ATTR((unused)),
 638                            int ref_offset EXT2FS_ATTR((unused)),
 639                            void *priv_data)
 640 {
 641         struct write_dir_struct *wd = (struct write_dir_struct *) priv_data;
 642         blk64_t blk;
 643         char    *dir;
 644
 645         if (*block_nr == 0)
 646                 return 0;
 647         if (blockcnt >= wd->outdir->num) {
 648                 e2fsck_read_bitmaps(wd->ctx);
 649                 blk = *block_nr;
 650                 /*
 651                  * In theory, we only release blocks from the end of the
 652                  * directory file, so it's fine to clobber a whole cluster at
 653                  * once.
 654                  */
 655                 if (blk % EXT2FS_CLUSTER_RATIO(fs) == 0) {
 656                         ext2fs_unmark_block_bitmap2(wd->ctx->block_found_map,
 657                                                     blk);
 658                         ext2fs_block_alloc_stats2(fs, blk, -1);
 659                         wd->cleared++;
 660                 }
 661                 *block_nr = 0;
 662                 return BLOCK_CHANGED;
 663         }
 664         if (blockcnt < 0)
 665                 return 0;
 666
 667         dir = wd->outdir->buf + (blockcnt * fs->blocksize);
 668         wd->err = ext2fs_write_dir_block3(fs, *block_nr, dir, 0);
 669         if (wd->err)
 670                 return BLOCK_ABORT;
 671         return 0;
 672 }
 673
 674 static errcode_t write_directory(e2fsck_t ctx, ext2_filsys fs,
 675                                  struct out_dir *outdir,
 676                                  ext2_ino_t ino, int compress)
 677 {
 678         struct write_dir_struct wd;
 679         errcode_t       retval;
 680         struct ext2_inode       inode;
 681
 682         retval = e2fsck_expand_directory(ctx, ino, -1, outdir->num);
 683         if (retval)
 684                 return retval;
 685
 686         wd.outdir = outdir;
 687         wd.err = 0;
 688         wd.ctx = ctx;
 689         wd.cleared = 0;
 690
 691         retval = ext2fs_block_iterate3(fs, ino, 0, 0,
 692                                        write_dir_block, &wd);
 693         if (retval)
 694                 return retval;
 695         if (wd.err)
 696                 return wd.err;
 697
 698         e2fsck_read_inode(ctx, ino, &inode, "rehash_dir");
 699         if (compress)
 700                 inode.i_flags &= ~EXT2_INDEX_FL;
 701         else
 702                 inode.i_flags |= EXT2_INDEX_FL;
 703         inode.i_size = outdir->num * fs->blocksize;
 704         ext2fs_iblk_sub_blocks(fs, &inode, wd.cleared);
 705         e2fsck_write_inode(ctx, ino, &inode, "rehash_dir");
 706
 707         return 0;
 708 }
 709
 710 errcode_t e2fsck_rehash_dir(e2fsck_t ctx, ext2_ino_t ino)
 711 {
 712         ext2_filsys             fs = ctx->fs;
 713         errcode_t               retval;
 714         struct ext2_inode       inode;
 715         char                    *dir_buf = 0;
 716         struct fill_dir_struct  fd;
 717         struct out_dir          outdir;
 718
 719         outdir.max = outdir.num = 0;
 720         outdir.buf = 0;
 721         outdir.hashes = 0;
 722         e2fsck_read_inode(ctx, ino, &inode, "rehash_dir");
 723
 724         retval = ENOMEM;
 725         fd.harray = 0;
 726         dir_buf = malloc(inode.i_size);
 727         if (!dir_buf)
 728                 goto errout;
 729
 730         fd.max_array = inode.i_size / 32;
 731         fd.num_array = 0;
 732         fd.harray = malloc(fd.max_array * sizeof(struct hash_entry));
 733         if (!fd.harray)
 734                 goto errout;
 735
 736         fd.ctx = ctx;
 737         fd.buf = dir_buf;
 738         fd.inode = &inode;
 739         fd.err = 0;
 740         fd.dir_size = 0;
 741         fd.compress = 0;
 742         if (!(fs->super->s_feature_compat & EXT2_FEATURE_COMPAT_DIR_INDEX) ||
 743             (inode.i_size / fs->blocksize) < 2)
 744                 fd.compress = 1;
 745         fd.parent = 0;
 746
 747 retry_nohash:
 748         /* Read in the entire directory into memory */
 749         retval = ext2fs_block_iterate3(fs, ino, 0, 0,
 750                                        fill_dir_block, &fd);
 751         if (fd.err) {
 752                 retval = fd.err;
 753                 goto errout;
 754         }
 755
 756         /*
 757          * If the entries read are less than a block, then don't index
 758          * the directory
 759          */
 760         if (!fd.compress && (fd.dir_size < (fs->blocksize - 24))) {
 761                 fd.compress = 1;
 762                 fd.dir_size = 0;
 763                 fd.num_array = 0;
 764                 goto retry_nohash;
 765         }
 766
 767 #if 0
 768         printf("%d entries (%d bytes) found in inode %d\n",
 769                fd.num_array, fd.dir_size, ino);
 770 #endif
 771
 772         /* Sort the list */
 773 resort:
 774         if (fd.compress)
 775                 qsort(fd.harray+2, fd.num_array-2, sizeof(struct hash_entry),
 776                       hash_cmp);
 777         else
 778                 qsort(fd.harray, fd.num_array, sizeof(struct hash_entry),
 779                       hash_cmp);
 780
 781         /*
 782          * Look for duplicates
 783          */
 784         if (duplicate_search_and_fix(ctx, fs, ino, &fd))
 785                 goto resort;
 786
 787         if (ctx->options & E2F_OPT_NO) {
 788                 retval = 0;
 789                 goto errout;
 790         }
 791
 792         /* Sort non-hashed directories by inode number */
 793         if (fd.compress)
 794                 qsort(fd.harray+2, fd.num_array-2,
 795                       sizeof(struct hash_entry), ino_cmp);
 796
 797         /*
 798          * Copy the directory entries.  In a htree directory these
 799          * will become the leaf nodes.
 800          */
 801         retval = copy_dir_entries(ctx, &fd, &outdir);
 802         if (retval)
 803                 goto errout;
 804
 805         free(dir_buf); dir_buf = 0;
 806
 807         if (!fd.compress) {
 808                 /* Calculate the interior nodes */
 809                 retval = calculate_tree(fs, &outdir, ino, fd.parent);
 810                 if (retval)
 811                         goto errout;
 812         }
 813
 814         retval = write_directory(ctx, fs, &outdir, ino, fd.compress);
 815         if (retval)
 816                 goto errout;
 817
 818 errout:
 819         free(dir_buf);
 820         free(fd.harray);
 821
 822         free_out_dir(&outdir);
 823         return retval;
 824 }
 825
 826 void e2fsck_rehash_directories(e2fsck_t ctx)
 827 {
 828         struct problem_context  pctx;
 829 #ifdef RESOURCE_TRACK
 830         struct resource_track   rtrack;
 831 #endif
 832         struct dir_info         *dir;
 833         ext2_u32_iterate        iter;
 834         struct dir_info_iter *  dirinfo_iter = 0;
 835         ext2_ino_t              ino;
 836         errcode_t               retval;
 837         int                     cur, max, all_dirs, first = 1;
 838
 839         init_resource_track(&rtrack, ctx->fs->io);
 840         all_dirs = ctx->options & E2F_OPT_COMPRESS_DIRS;
 841
 842         if (!ctx->dirs_to_hash && !all_dirs)
 843                 return;
 844
 845         e2fsck_get_lost_and_found(ctx, 0);
 846
 847         clear_problem_context(&pctx);
 848
 849         cur = 0;
 850         if (all_dirs) {
 851                 dirinfo_iter = e2fsck_dir_info_iter_begin(ctx);
 852                 max = e2fsck_get_num_dirinfo(ctx);
 853         } else {
 854                 retval = ext2fs_u32_list_iterate_begin(ctx->dirs_to_hash,
 855                                                        &iter);
 856                 if (retval) {
 857                         pctx.errcode = retval;
 858                         fix_problem(ctx, PR_3A_OPTIMIZE_ITER, &pctx);
 859                         return;
 860                 }
 861                 max = ext2fs_u32_list_count(ctx->dirs_to_hash);
 862         }
 863         while (1) {
 864                 if (all_dirs) {
 865                         if ((dir = e2fsck_dir_info_iter(ctx,
 866                                                         dirinfo_iter)) == 0)
 867                                 break;
 868                         ino = dir->ino;
 869                 } else {
 870                         if (!ext2fs_u32_list_iterate(iter, &ino))
 871                                 break;
 872                 }
 873                 if (ino == ctx->lost_and_found)
 874                         continue;
 875                 pctx.dir = ino;
 876                 if (first) {
 877                         fix_problem(ctx, PR_3A_PASS_HEADER, &pctx);
 878                         first = 0;
 879                 }
 880 #if 0
 881                 fix_problem(ctx, PR_3A_OPTIMIZE_DIR, &pctx);
 882 #endif
 883                 pctx.errcode = e2fsck_rehash_dir(ctx, ino);
 884                 if (pctx.errcode) {
 885                         end_problem_latch(ctx, PR_LATCH_OPTIMIZE_DIR);
 886                         fix_problem(ctx, PR_3A_OPTIMIZE_DIR_ERR, &pctx);
 887                 }
 888                 if (ctx->progress && !ctx->progress_fd)
 889                         e2fsck_simple_progress(ctx, "Rebuilding directory",
 890                                100.0 * (float) (++cur) / (float) max, ino);
 891         }
 892         end_problem_latch(ctx, PR_LATCH_OPTIMIZE_DIR);
 893         if (all_dirs)
 894                 e2fsck_dir_info_iter_end(ctx, dirinfo_iter);
 895         else
 896                 ext2fs_u32_list_iterate_end(iter);
 897
 898         if (ctx->dirs_to_hash)
 899                 ext2fs_u32_list_free(ctx->dirs_to_hash);
 900         ctx->dirs_to_hash = 0;
 901
 902         print_resource_track(ctx, "Pass 3A", &rtrack, ctx->fs->io);
 903 }