sys/fs/ext2fs/ext2_htree.c

   1 /*-
   2  * SPDX-License-Identifier: BSD-2-Clause-FreeBSD
   3  *
   4  * Copyright (c) 2010, 2012 Zheng Liu <lz@freebsd.org>
   5  * Copyright (c) 2012, Vyacheslav Matyushin
   6  * All rights reserved.
   7  *
   8  * Redistribution and use in source and binary forms, with or without
   9  * modification, are permitted provided that the following conditions
  10  * are met:
  11  * 1. Redistributions of source code must retain the above copyright
  12  *    notice, this list of conditions and the following disclaimer.
  13  * 2. Redistributions in binary form must reproduce the above copyright
  14  *    notice, this list of conditions and the following disclaimer in the
  15  *    documentation and/or other materials provided with the distribution.
  16  *
  17  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  18  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  19  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  20  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  21  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  22  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  23  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  24  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  25  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  26  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  27  * SUCH DAMAGE.
  28  *
  29  * $FreeBSD$
  30  */
  31
  32 #include <sys/param.h>
  33 #include <sys/endian.h>
  34 #include <sys/systm.h>
  35 #include <sys/namei.h>
  36 #include <sys/bio.h>
  37 #include <sys/buf.h>
  38 #include <sys/endian.h>
  39 #include <sys/mount.h>
  40 #include <sys/vnode.h>
  41 #include <sys/malloc.h>
  42 #include <sys/dirent.h>
  43 #include <sys/sysctl.h>
  44
  45 #include <ufs/ufs/dir.h>
  46
  47 #include <fs/ext2fs/inode.h>
  48 #include <fs/ext2fs/ext2_mount.h>
  49 #include <fs/ext2fs/ext2fs.h>
  50 #include <fs/ext2fs/fs.h>
  51 #include <fs/ext2fs/ext2_extern.h>
  52 #include <fs/ext2fs/ext2_dinode.h>
  53 #include <fs/ext2fs/ext2_dir.h>
  54 #include <fs/ext2fs/htree.h>
  55
  56 static void     ext2_append_entry(char *block, uint32_t blksize,
  57                     struct ext2fs_direct_2 *last_entry,
  58                     struct ext2fs_direct_2 *new_entry);
  59 static int      ext2_htree_append_block(struct vnode *vp, char *data,
  60                     struct componentname *cnp, uint32_t blksize);
  61 static int      ext2_htree_check_next(struct inode *ip, uint32_t hash,
  62                     const char *name, struct ext2fs_htree_lookup_info *info);
  63 static int      ext2_htree_cmp_sort_entry(const void *e1, const void *e2);
  64 static int      ext2_htree_find_leaf(struct inode *ip, const char *name,
  65                     int namelen, uint32_t *hash, uint8_t *hash_version,
  66                     struct ext2fs_htree_lookup_info *info);
  67 static uint32_t ext2_htree_get_block(struct ext2fs_htree_entry *ep);
  68 static uint16_t ext2_htree_get_count(struct ext2fs_htree_entry *ep);
  69 static uint32_t ext2_htree_get_hash(struct ext2fs_htree_entry *ep);
  70 static uint16_t ext2_htree_get_limit(struct ext2fs_htree_entry *ep);
  71 static void     ext2_htree_insert_entry_to_level(struct ext2fs_htree_lookup_level *level,
  72                     uint32_t hash, uint32_t blk);
  73 static void     ext2_htree_insert_entry(struct ext2fs_htree_lookup_info *info,
  74                     uint32_t hash, uint32_t blk);
  75 static uint32_t ext2_htree_node_limit(struct inode *ip);
  76 static void     ext2_htree_set_block(struct ext2fs_htree_entry *ep,
  77                     uint32_t blk);
  78 static void     ext2_htree_set_count(struct ext2fs_htree_entry *ep,
  79                     uint16_t cnt);
  80 static void     ext2_htree_set_hash(struct ext2fs_htree_entry *ep,
  81                     uint32_t hash);
  82 static void     ext2_htree_set_limit(struct ext2fs_htree_entry *ep,
  83                     uint16_t limit);
  84 static int      ext2_htree_split_dirblock(char *block1, char *block2,
  85                     uint32_t blksize, uint32_t *hash_seed, uint8_t hash_version,
  86                     uint32_t *split_hash, struct  ext2fs_direct_2 *entry);
  87 static void     ext2_htree_release(struct ext2fs_htree_lookup_info *info);
  88 static uint32_t ext2_htree_root_limit(struct inode *ip, int len);
  89 static int      ext2_htree_writebuf(struct ext2fs_htree_lookup_info *info);
  90
  91 int
  92 ext2_htree_has_idx(struct inode *ip)
  93 {
  94         if (EXT2_HAS_COMPAT_FEATURE(ip->i_e2fs, EXT2F_COMPAT_DIRHASHINDEX) &&
  95             ip->i_flag & IN_E3INDEX)
  96                 return (1);
  97         else
  98                 return (0);
  99 }
 100
 101 static int
 102 ext2_htree_check_next(struct inode *ip, uint32_t hash, const char *name,
 103     struct ext2fs_htree_lookup_info *info)
 104 {
 105         struct vnode *vp = ITOV(ip);
 106         struct ext2fs_htree_lookup_level *level;
 107         struct buf *bp;
 108         uint32_t next_hash;
 109         int idx = info->h_levels_num - 1;
 110         int levels = 0;
 111
 112         do {
 113                 level = &info->h_levels[idx];
 114                 level->h_entry++;
 115                 if (level->h_entry < level->h_entries +
 116                     ext2_htree_get_count(level->h_entries))
 117                         break;
 118                 if (idx == 0)
 119                         return (0);
 120                 idx--;
 121                 levels++;
 122         } while (1);
 123
 124         next_hash = ext2_htree_get_hash(level->h_entry);
 125         if ((hash & 1) == 0) {
 126                 if (hash != (next_hash & ~1))
 127                         return (0);
 128         }
 129
 130         while (levels > 0) {
 131                 levels--;
 132                 if (ext2_blkatoff(vp, ext2_htree_get_block(level->h_entry) *
 133                     ip->i_e2fs->e2fs_bsize, NULL, &bp) != 0)
 134                         return (0);
 135                 level = &info->h_levels[idx + 1];
 136                 brelse(level->h_bp);
 137                 level->h_bp = bp;
 138                 level->h_entry = level->h_entries =
 139                     ((struct ext2fs_htree_node *)bp->b_data)->h_entries;
 140         }
 141
 142         return (1);
 143 }
 144
 145 static uint32_t
 146 ext2_htree_get_block(struct ext2fs_htree_entry *ep)
 147 {
 148         return (ep->h_blk & 0x00FFFFFF);
 149 }
 150
 151 static void
 152 ext2_htree_set_block(struct ext2fs_htree_entry *ep, uint32_t blk)
 153 {
 154         ep->h_blk = blk;
 155 }
 156
 157 static uint16_t
 158 ext2_htree_get_count(struct ext2fs_htree_entry *ep)
 159 {
 160         return (((struct ext2fs_htree_count *)(ep))->h_entries_num);
 161 }
 162
 163 static void
 164 ext2_htree_set_count(struct ext2fs_htree_entry *ep, uint16_t cnt)
 165 {
 166         ((struct ext2fs_htree_count *)(ep))->h_entries_num = cnt;
 167 }
 168
 169 static uint32_t
 170 ext2_htree_get_hash(struct ext2fs_htree_entry *ep)
 171 {
 172         return (ep->h_hash);
 173 }
 174
 175 static uint16_t
 176 ext2_htree_get_limit(struct ext2fs_htree_entry *ep)
 177 {
 178         return (((struct ext2fs_htree_count *)(ep))->h_entries_max);
 179 }
 180
 181 static void
 182 ext2_htree_set_hash(struct ext2fs_htree_entry *ep, uint32_t hash)
 183 {
 184         ep->h_hash = hash;
 185 }
 186
 187 static void
 188 ext2_htree_set_limit(struct ext2fs_htree_entry *ep, uint16_t limit)
 189 {
 190         ((struct ext2fs_htree_count *)(ep))->h_entries_max = limit;
 191 }
 192
 193 static void
 194 ext2_htree_release(struct ext2fs_htree_lookup_info *info)
 195 {
 196         u_int i;
 197
 198         for (i = 0; i < info->h_levels_num; i++) {
 199                 struct buf *bp = info->h_levels[i].h_bp;
 200
 201                 if (bp != NULL)
 202                         brelse(bp);
 203         }
 204 }
 205
 206 static uint32_t
 207 ext2_htree_root_limit(struct inode *ip, int len)
 208 {
 209         uint32_t space;
 210
 211         space = ip->i_e2fs->e2fs_bsize - EXT2_DIR_REC_LEN(1) -
 212             EXT2_DIR_REC_LEN(2) - len;
 213         return (space / sizeof(struct ext2fs_htree_entry));
 214 }
 215
 216 static uint32_t
 217 ext2_htree_node_limit(struct inode *ip)
 218 {
 219         struct m_ext2fs *fs;
 220         uint32_t space;
 221
 222         fs = ip->i_e2fs;
 223         space = fs->e2fs_bsize - EXT2_DIR_REC_LEN(0);
 224
 225         return (space / sizeof(struct ext2fs_htree_entry));
 226 }
 227
 228 static int
 229 ext2_htree_find_leaf(struct inode *ip, const char *name, int namelen,
 230     uint32_t *hash, uint8_t *hash_ver,
 231     struct ext2fs_htree_lookup_info *info)
 232 {
 233         struct vnode *vp;
 234         struct ext2fs *fs;
 235         struct m_ext2fs *m_fs;
 236         struct buf *bp = NULL;
 237         struct ext2fs_htree_root *rootp;
 238         struct ext2fs_htree_entry *entp, *start, *end, *middle, *found;
 239         struct ext2fs_htree_lookup_level *level_info;
 240         uint32_t hash_major = 0, hash_minor = 0;
 241         uint32_t levels, cnt;
 242         uint8_t hash_version;
 243
 244         if (name == NULL || info == NULL)
 245                 return (-1);
 246
 247         vp = ITOV(ip);
 248         fs = ip->i_e2fs->e2fs;
 249         m_fs = ip->i_e2fs;
 250
 251         if (ext2_blkatoff(vp, 0, NULL, &bp) != 0)
 252                 return (-1);
 253
 254         info->h_levels_num = 1;
 255         info->h_levels[0].h_bp = bp;
 256         rootp = (struct ext2fs_htree_root *)bp->b_data;
 257         if (rootp->h_info.h_hash_version != EXT2_HTREE_LEGACY &&
 258             rootp->h_info.h_hash_version != EXT2_HTREE_HALF_MD4 &&
 259             rootp->h_info.h_hash_version != EXT2_HTREE_TEA)
 260                 goto error;
 261
 262         hash_version = rootp->h_info.h_hash_version;
 263         if (hash_version <= EXT2_HTREE_TEA)
 264                 hash_version += m_fs->e2fs_uhash;
 265         *hash_ver = hash_version;
 266
 267         ext2_htree_hash(name, namelen, fs->e3fs_hash_seed,
 268             hash_version, &hash_major, &hash_minor);
 269         *hash = hash_major;
 270
 271         if ((levels = rootp->h_info.h_ind_levels) > 1)
 272                 goto error;
 273
 274         entp = (struct ext2fs_htree_entry *)(((char *)&rootp->h_info) +
 275             rootp->h_info.h_info_len);
 276
 277         if (ext2_htree_get_limit(entp) !=
 278             ext2_htree_root_limit(ip, rootp->h_info.h_info_len))
 279                 goto error;
 280
 281         while (1) {
 282                 cnt = ext2_htree_get_count(entp);
 283                 if (cnt == 0 || cnt > ext2_htree_get_limit(entp))
 284                         goto error;
 285
 286                 start = entp + 1;
 287                 end = entp + cnt - 1;
 288                 while (start <= end) {
 289                         middle = start + (end - start) / 2;
 290                         if (ext2_htree_get_hash(middle) > hash_major)
 291                                 end = middle - 1;
 292                         else
 293                                 start = middle + 1;
 294                 }
 295                 found = start - 1;
 296
 297                 level_info = &(info->h_levels[info->h_levels_num - 1]);
 298                 level_info->h_bp = bp;
 299                 level_info->h_entries = entp;
 300                 level_info->h_entry = found;
 301                 if (levels == 0)
 302                         return (0);
 303                 levels--;
 304                 if (ext2_blkatoff(vp,
 305                     ext2_htree_get_block(found) * m_fs->e2fs_bsize,
 306                     NULL, &bp) != 0)
 307                         goto error;
 308                 entp = ((struct ext2fs_htree_node *)bp->b_data)->h_entries;
 309                 info->h_levels_num++;
 310                 info->h_levels[info->h_levels_num - 1].h_bp = bp;
 311         }
 312
 313 error:
 314         ext2_htree_release(info);
 315         return (-1);
 316 }
 317
 318 /*
 319  * Try to lookup a directory entry in HTree index
 320  */
 321 int
 322 ext2_htree_lookup(struct inode *ip, const char *name, int namelen,
 323     struct buf **bpp, int *entryoffp, doff_t *offp,
 324     doff_t *prevoffp, doff_t *endusefulp,
 325     struct ext2fs_searchslot *ss)
 326 {
 327         struct vnode *vp;
 328         struct ext2fs_htree_lookup_info info;
 329         struct ext2fs_htree_entry *leaf_node;
 330         struct m_ext2fs *m_fs;
 331         struct buf *bp;
 332         uint32_t blk;
 333         uint32_t dirhash;
 334         uint32_t bsize;
 335         uint8_t hash_version;
 336         int search_next;
 337         int found = 0;
 338
 339         m_fs = ip->i_e2fs;
 340         bsize = m_fs->e2fs_bsize;
 341         vp = ITOV(ip);
 342
 343         /* TODO: print error msg because we don't lookup '.' and '..' */
 344
 345         memset(&info, 0, sizeof(info));
 346         if (ext2_htree_find_leaf(ip, name, namelen, &dirhash,
 347             &hash_version, &info))
 348                 return (-1);
 349
 350         do {
 351                 leaf_node = info.h_levels[info.h_levels_num - 1].h_entry;
 352                 blk = ext2_htree_get_block(leaf_node);
 353                 if (ext2_blkatoff(vp, blk * bsize, NULL, &bp) != 0) {
 354                         ext2_htree_release(&info);
 355                         return (-1);
 356                 }
 357
 358                 *offp = blk * bsize;
 359                 *entryoffp = 0;
 360                 *prevoffp = blk * bsize;
 361                 *endusefulp = blk * bsize;
 362
 363                 if (ss->slotstatus == NONE) {
 364                         ss->slotoffset = -1;
 365                         ss->slotfreespace = 0;
 366                 }
 367
 368                 if (ext2_search_dirblock(ip, bp->b_data, &found,
 369                     name, namelen, entryoffp, offp, prevoffp,
 370                     endusefulp, ss) != 0) {
 371                         brelse(bp);
 372                         ext2_htree_release(&info);
 373                         return (-1);
 374                 }
 375
 376                 if (found) {
 377                         *bpp = bp;
 378                         ext2_htree_release(&info);
 379                         return (0);
 380                 }
 381
 382                 brelse(bp);
 383                 search_next = ext2_htree_check_next(ip, dirhash, name, &info);
 384         } while (search_next);
 385
 386         ext2_htree_release(&info);
 387         return (ENOENT);
 388 }
 389
 390 static int
 391 ext2_htree_append_block(struct vnode *vp, char *data,
 392     struct componentname *cnp, uint32_t blksize)
 393 {
 394         struct iovec aiov;
 395         struct uio auio;
 396         struct inode *dp = VTOI(vp);
 397         uint64_t cursize, newsize;
 398         int error;
 399
 400         cursize = roundup(dp->i_size, blksize);
 401         newsize = cursize + blksize;
 402
 403         auio.uio_offset = cursize;
 404         auio.uio_resid = blksize;
 405         aiov.iov_len = blksize;
 406         aiov.iov_base = data;
 407         auio.uio_iov = &aiov;
 408         auio.uio_iovcnt = 1;
 409         auio.uio_rw = UIO_WRITE;
 410         auio.uio_segflg = UIO_SYSSPACE;
 411         error = VOP_WRITE(vp, &auio, IO_SYNC, cnp->cn_cred);
 412         if (!error)
 413                 dp->i_size = newsize;
 414
 415         return (error);
 416 }
 417
 418 static int
 419 ext2_htree_writebuf(struct ext2fs_htree_lookup_info *info)
 420 {
 421         int i, error;
 422
 423         for (i = 0; i < info->h_levels_num; i++) {
 424                 struct buf *bp = info->h_levels[i].h_bp;
 425
 426                 error = bwrite(bp);
 427                 if (error)
 428                         return (error);
 429         }
 430
 431         return (0);
 432 }
 433
 434 static void
 435 ext2_htree_insert_entry_to_level(struct ext2fs_htree_lookup_level *level,
 436     uint32_t hash, uint32_t blk)
 437 {
 438         struct ext2fs_htree_entry *target;
 439         int entries_num;
 440
 441         target = level->h_entry + 1;
 442         entries_num = ext2_htree_get_count(level->h_entries);
 443
 444         memmove(target + 1, target, (char *)(level->h_entries + entries_num) -
 445             (char *)target);
 446         ext2_htree_set_block(target, blk);
 447         ext2_htree_set_hash(target, hash);
 448         ext2_htree_set_count(level->h_entries, entries_num + 1);
 449 }
 450
 451 /*
 452  * Insert an index entry to the index node.
 453  */
 454 static void
 455 ext2_htree_insert_entry(struct ext2fs_htree_lookup_info *info,
 456     uint32_t hash, uint32_t blk)
 457 {
 458         struct ext2fs_htree_lookup_level *level;
 459
 460         level = &info->h_levels[info->h_levels_num - 1];
 461         ext2_htree_insert_entry_to_level(level, hash, blk);
 462 }
 463
 464 /*
 465  * Compare two entry sort descriptors by name hash value.
 466  * This is used together with qsort.
 467  */
 468 static int
 469 ext2_htree_cmp_sort_entry(const void *e1, const void *e2)
 470 {
 471         const struct ext2fs_htree_sort_entry *entry1, *entry2;
 472
 473         entry1 = (const struct ext2fs_htree_sort_entry *)e1;
 474         entry2 = (const struct ext2fs_htree_sort_entry *)e2;
 475
 476         if (entry1->h_hash < entry2->h_hash)
 477                 return (-1);
 478         if (entry1->h_hash > entry2->h_hash)
 479                 return (1);
 480         return (0);
 481 }
 482
 483 /*
 484  * Append an entry to the end of the directory block.
 485  */
 486 static void
 487 ext2_append_entry(char *block, uint32_t blksize,
 488     struct ext2fs_direct_2 *last_entry,
 489     struct ext2fs_direct_2 *new_entry)
 490 {
 491         uint16_t entry_len;
 492
 493         entry_len = EXT2_DIR_REC_LEN(last_entry->e2d_namlen);
 494         last_entry->e2d_reclen = entry_len;
 495         last_entry = (struct ext2fs_direct_2 *)((char *)last_entry + entry_len);
 496         new_entry->e2d_reclen = block + blksize - (char *)last_entry;
 497         memcpy(last_entry, new_entry, EXT2_DIR_REC_LEN(new_entry->e2d_namlen));
 498 }
 499
 500 /*
 501  * Move half of entries from the old directory block to the new one.
 502  */
 503 static int
 504 ext2_htree_split_dirblock(char *block1, char *block2, uint32_t blksize,
 505     uint32_t *hash_seed, uint8_t hash_version,
 506     uint32_t *split_hash, struct ext2fs_direct_2 *entry)
 507 {
 508         int entry_cnt = 0;
 509         int size = 0;
 510         int i, k;
 511         uint32_t offset;
 512         uint16_t entry_len = 0;
 513         uint32_t entry_hash;
 514         struct ext2fs_direct_2 *ep, *last;
 515         char *dest;
 516         struct ext2fs_htree_sort_entry *sort_info;
 517
 518         ep = (struct ext2fs_direct_2 *)block1;
 519         dest = block2;
 520         sort_info = (struct ext2fs_htree_sort_entry *)
 521             ((char *)block2 + blksize);
 522
 523         /*
 524          * Calculate name hash value for the entry which is to be added.
 525          */
 526         ext2_htree_hash(entry->e2d_name, entry->e2d_namlen, hash_seed,
 527             hash_version, &entry_hash, NULL);
 528
 529         /*
 530          * Fill in directory entry sort descriptors.
 531          */
 532         while ((char *)ep < block1 + blksize) {
 533                 if (ep->e2d_ino && ep->e2d_namlen) {
 534                         entry_cnt++;
 535                         sort_info--;
 536                         sort_info->h_size = ep->e2d_reclen;
 537                         sort_info->h_offset = (char *)ep - block1;
 538                         ext2_htree_hash(ep->e2d_name, ep->e2d_namlen,
 539                             hash_seed, hash_version,
 540                             &sort_info->h_hash, NULL);
 541                 }
 542                 ep = (struct ext2fs_direct_2 *)
 543                     ((char *)ep + ep->e2d_reclen);
 544         }
 545
 546         /*
 547          * Sort directory entry descriptors by name hash value.
 548          */
 549         qsort(sort_info, entry_cnt, sizeof(struct ext2fs_htree_sort_entry),
 550             ext2_htree_cmp_sort_entry);
 551
 552         /*
 553          * Count the number of entries to move to directory block 2.
 554          */
 555         for (i = entry_cnt - 1; i >= 0; i--) {
 556                 if (sort_info[i].h_size + size > blksize / 2)
 557                         break;
 558                 size += sort_info[i].h_size;
 559         }
 560
 561         *split_hash = sort_info[i + 1].h_hash;
 562
 563         /*
 564          * Set collision bit.
 565          */
 566         if (*split_hash == sort_info[i].h_hash)
 567                 *split_hash += 1;
 568
 569         /*
 570          * Move half of directory entries from block 1 to block 2.
 571          */
 572         for (k = i + 1; k < entry_cnt; k++) {
 573                 ep = (struct ext2fs_direct_2 *)((char *)block1 +
 574                     sort_info[k].h_offset);
 575                 entry_len = EXT2_DIR_REC_LEN(ep->e2d_namlen);
 576                 memcpy(dest, ep, entry_len);
 577                 ((struct ext2fs_direct_2 *)dest)->e2d_reclen = entry_len;
 578                 /* Mark directory entry as unused. */
 579                 ep->e2d_ino = 0;
 580                 dest += entry_len;
 581         }
 582         dest -= entry_len;
 583
 584         /* Shrink directory entries in block 1. */
 585         last = (struct ext2fs_direct_2 *)block1;
 586         entry_len = 0;
 587         for (offset = 0; offset < blksize; ) {
 588                 ep = (struct ext2fs_direct_2 *)(block1 + offset);
 589                 offset += ep->e2d_reclen;
 590                 if (ep->e2d_ino) {
 591                         last = (struct ext2fs_direct_2 *)
 592                             ((char *)last + entry_len);
 593                         entry_len = EXT2_DIR_REC_LEN(ep->e2d_namlen);
 594                         memcpy((void *)last, (void *)ep, entry_len);
 595                         last->e2d_reclen = entry_len;
 596                 }
 597         }
 598
 599         if (entry_hash >= *split_hash) {
 600                 /* Add entry to block 2. */
 601                 ext2_append_entry(block2, blksize,
 602                     (struct ext2fs_direct_2 *)dest, entry);
 603
 604                 /* Adjust length field of last entry of block 1. */
 605                 last->e2d_reclen = block1 + blksize - (char *)last;
 606         } else {
 607                 /* Add entry to block 1. */
 608                 ext2_append_entry(block1, blksize, last, entry);
 609
 610                 /* Adjust length field of last entry of block 2. */
 611                 ((struct ext2fs_direct_2 *)dest)->e2d_reclen =
 612                     block2 + blksize - dest;
 613         }
 614
 615         return (0);
 616 }
 617
 618 /*
 619  * Create an HTree index for a directory
 620  */
 621 int
 622 ext2_htree_create_index(struct vnode *vp, struct componentname *cnp,
 623     struct ext2fs_direct_2 *new_entry)
 624 {
 625         struct buf *bp = NULL;
 626         struct inode *dp;
 627         struct ext2fs *fs;
 628         struct m_ext2fs *m_fs;
 629         struct ext2fs_direct_2 *ep, *dotdot;
 630         struct ext2fs_htree_root *root;
 631         struct ext2fs_htree_lookup_info info;
 632         uint32_t blksize, dirlen, split_hash;
 633         uint8_t hash_version;
 634         char *buf1 = NULL;
 635         char *buf2 = NULL;
 636         int error = 0;
 637
 638         dp = VTOI(vp);
 639         fs = dp->i_e2fs->e2fs;
 640         m_fs = dp->i_e2fs;
 641         blksize = m_fs->e2fs_bsize;
 642
 643         buf1 = malloc(blksize, M_TEMP, M_WAITOK | M_ZERO);
 644         buf2 = malloc(blksize, M_TEMP, M_WAITOK | M_ZERO);
 645
 646         if ((error = ext2_blkatoff(vp, 0, NULL, &bp)) != 0)
 647                 goto out;
 648
 649         root = (struct ext2fs_htree_root *)bp->b_data;
 650         dotdot = (struct ext2fs_direct_2 *)((char *)&(root->h_dotdot));
 651         ep = (struct ext2fs_direct_2 *)((char *)dotdot + dotdot->e2d_reclen);
 652         dirlen = (char *)root + blksize - (char *)ep;
 653         memcpy(buf1, ep, dirlen);
 654         ep = (struct ext2fs_direct_2 *)buf1;
 655         while ((char *)ep < buf1 + dirlen)
 656                 ep = (struct ext2fs_direct_2 *)
 657                     ((char *)ep + ep->e2d_reclen);
 658         ep->e2d_reclen = buf1 + blksize - (char *)ep;
 659
 660         dp->i_flag |= IN_E3INDEX;
 661
 662         /*
 663          * Initialize index root.
 664          */
 665         dotdot->e2d_reclen = blksize - EXT2_DIR_REC_LEN(1);
 666         memset(&root->h_info, 0, sizeof(root->h_info));
 667         root->h_info.h_hash_version = fs->e3fs_def_hash_version;
 668         root->h_info.h_info_len = sizeof(root->h_info);
 669         ext2_htree_set_block(root->h_entries, 1);
 670         ext2_htree_set_count(root->h_entries, 1);
 671         ext2_htree_set_limit(root->h_entries,
 672             ext2_htree_root_limit(dp, sizeof(root->h_info)));
 673
 674         memset(&info, 0, sizeof(info));
 675         info.h_levels_num = 1;
 676         info.h_levels[0].h_entries = root->h_entries;
 677         info.h_levels[0].h_entry = root->h_entries;
 678
 679         hash_version = root->h_info.h_hash_version;
 680         if (hash_version <= EXT2_HTREE_TEA)
 681                 hash_version += m_fs->e2fs_uhash;
 682         ext2_htree_split_dirblock(buf1, buf2, blksize, fs->e3fs_hash_seed,
 683             hash_version, &split_hash, new_entry);
 684         ext2_htree_insert_entry(&info, split_hash, 2);
 685
 686         /*
 687          * Write directory block 0.
 688          */
 689         if (DOINGASYNC(vp)) {
 690                 bdwrite(bp);
 691                 error = 0;
 692         } else {
 693                 error = bwrite(bp);
 694         }
 695         dp->i_flag |= IN_CHANGE | IN_UPDATE;
 696         if (error)
 697                 goto out;
 698
 699         /*
 700          * Write directory block 1.
 701          */
 702         error = ext2_htree_append_block(vp, buf1, cnp, blksize);
 703         if (error)
 704                 goto out1;
 705
 706         /*
 707          * Write directory block 2.
 708          */
 709         error = ext2_htree_append_block(vp, buf2, cnp, blksize);
 710
 711         free(buf1, M_TEMP);
 712         free(buf2, M_TEMP);
 713         return (error);
 714 out:
 715         if (bp != NULL)
 716                 brelse(bp);
 717 out1:
 718         free(buf1, M_TEMP);
 719         free(buf2, M_TEMP);
 720         return (error);
 721 }
 722
 723 /*
 724  * Add an entry to the directory using htree index.
 725  */
 726 int
 727 ext2_htree_add_entry(struct vnode *dvp, struct ext2fs_direct_2 *entry,
 728     struct componentname *cnp)
 729 {
 730         struct ext2fs_htree_entry *entries, *leaf_node;
 731         struct ext2fs_htree_lookup_info info;
 732         struct buf *bp = NULL;
 733         struct ext2fs *fs;
 734         struct m_ext2fs *m_fs;
 735         struct inode *ip;
 736         uint16_t ent_num;
 737         uint32_t dirhash, split_hash;
 738         uint32_t blksize, blknum;
 739         uint64_t cursize, dirsize;
 740         uint8_t hash_version;
 741         char *newdirblock = NULL;
 742         char *newidxblock = NULL;
 743         struct ext2fs_htree_node *dst_node;
 744         struct ext2fs_htree_entry *dst_entries;
 745         struct ext2fs_htree_entry *root_entires;
 746         struct buf *dst_bp = NULL;
 747         int error, write_bp = 0, write_dst_bp = 0, write_info = 0;
 748
 749         ip = VTOI(dvp);
 750         m_fs = ip->i_e2fs;
 751         fs = m_fs->e2fs;
 752         blksize = m_fs->e2fs_bsize;
 753
 754         if (ip->i_count != 0)
 755                 return ext2_add_entry(dvp, entry);
 756
 757         /* Target directory block is full, split it */
 758         memset(&info, 0, sizeof(info));
 759         error = ext2_htree_find_leaf(ip, entry->e2d_name, entry->e2d_namlen,
 760             &dirhash, &hash_version, &info);
 761         if (error)
 762                 return (error);
 763
 764         entries = info.h_levels[info.h_levels_num - 1].h_entries;
 765         ent_num = ext2_htree_get_count(entries);
 766         if (ent_num == ext2_htree_get_limit(entries)) {
 767                 /* Split the index node. */
 768                 root_entires = info.h_levels[0].h_entries;
 769                 newidxblock = malloc(blksize, M_TEMP, M_WAITOK | M_ZERO);
 770                 dst_node = (struct ext2fs_htree_node *)newidxblock;
 771                 memset(&dst_node->h_fake_dirent, 0,
 772                     sizeof(dst_node->h_fake_dirent));
 773                 dst_node->h_fake_dirent.e2d_reclen = blksize;
 774
 775                 cursize = roundup(ip->i_size, blksize);
 776                 dirsize = cursize + blksize;
 777                 blknum = dirsize / blksize - 1;
 778
 779                 error = ext2_htree_append_block(dvp, newidxblock,
 780                     cnp, blksize);
 781                 if (error)
 782                         goto finish;
 783                 error = ext2_blkatoff(dvp, cursize, NULL, &dst_bp);
 784                 if (error)
 785                         goto finish;
 786                 dst_node = (struct ext2fs_htree_node *)dst_bp->b_data;
 787                 dst_entries = dst_node->h_entries;
 788
 789                 if (info.h_levels_num == 2) {
 790                         uint16_t src_ent_num, dst_ent_num;
 791
 792                         if (ext2_htree_get_count(root_entires) ==
 793                             ext2_htree_get_limit(root_entires)) {
 794                                 /* Directory index is full */
 795                                 error = EIO;
 796                                 goto finish;
 797                         }
 798
 799                         src_ent_num = ent_num / 2;
 800                         dst_ent_num = ent_num - src_ent_num;
 801                         split_hash = ext2_htree_get_hash(entries + src_ent_num);
 802
 803                         /* Move half of index entries to the new index node */
 804                         memcpy(dst_entries, entries + src_ent_num,
 805                             dst_ent_num * sizeof(struct ext2fs_htree_entry));
 806                         ext2_htree_set_count(entries, src_ent_num);
 807                         ext2_htree_set_count(dst_entries, dst_ent_num);
 808                         ext2_htree_set_limit(dst_entries,
 809                             ext2_htree_node_limit(ip));
 810
 811                         if (info.h_levels[1].h_entry >= entries + src_ent_num) {
 812                                 struct buf *tmp = info.h_levels[1].h_bp;
 813
 814                                 info.h_levels[1].h_bp = dst_bp;
 815                                 dst_bp = tmp;
 816
 817                                 info.h_levels[1].h_entry =
 818                                     info.h_levels[1].h_entry -
 819                                     (entries + src_ent_num) +
 820                                     dst_entries;
 821                                 info.h_levels[1].h_entries = dst_entries;
 822                         }
 823                         ext2_htree_insert_entry_to_level(&info.h_levels[0],
 824                             split_hash, blknum);
 825
 826                         /* Write new index node to disk */
 827                         error = bwrite(dst_bp);
 828                         ip->i_flag |= IN_CHANGE | IN_UPDATE;
 829                         if (error)
 830                                 goto finish;
 831                         write_dst_bp = 1;
 832                 } else {
 833                         /* Create second level for htree index */
 834                         struct ext2fs_htree_root *idx_root;
 835
 836                         memcpy(dst_entries, entries,
 837                             ent_num * sizeof(struct ext2fs_htree_entry));
 838                         ext2_htree_set_limit(dst_entries,
 839                             ext2_htree_node_limit(ip));
 840
 841                         idx_root = (struct ext2fs_htree_root *)
 842                             info.h_levels[0].h_bp->b_data;
 843                         idx_root->h_info.h_ind_levels = 1;
 844
 845                         ext2_htree_set_count(entries, 1);
 846                         ext2_htree_set_block(entries, blknum);
 847
 848                         info.h_levels_num = 2;
 849                         info.h_levels[1].h_entries = dst_entries;
 850                         info.h_levels[1].h_entry = info.h_levels[0].h_entry -
 851                             info.h_levels[0].h_entries + dst_entries;
 852                         info.h_levels[1].h_bp = dst_bp;
 853                         dst_bp = NULL;
 854                 }
 855         }
 856
 857         leaf_node = info.h_levels[info.h_levels_num - 1].h_entry;
 858         blknum = ext2_htree_get_block(leaf_node);
 859         error = ext2_blkatoff(dvp, blknum * blksize, NULL, &bp);
 860         if (error)
 861                 goto finish;
 862
 863         /* Split target directory block */
 864         newdirblock = malloc(blksize, M_TEMP, M_WAITOK | M_ZERO);
 865         ext2_htree_split_dirblock((char *)bp->b_data, newdirblock, blksize,
 866             fs->e3fs_hash_seed, hash_version, &split_hash, entry);
 867         cursize = roundup(ip->i_size, blksize);
 868         dirsize = cursize + blksize;
 869         blknum = dirsize / blksize - 1;
 870
 871         /* Add index entry for the new directory block */
 872         ext2_htree_insert_entry(&info, split_hash, blknum);
 873
 874         /* Write the new directory block to the end of the directory */
 875         error = ext2_htree_append_block(dvp, newdirblock, cnp, blksize);
 876         if (error)
 877                 goto finish;
 878
 879         /* Write the target directory block */
 880         error = bwrite(bp);
 881         ip->i_flag |= IN_CHANGE | IN_UPDATE;
 882         if (error)
 883                 goto finish;
 884         write_bp = 1;
 885
 886         /* Write the index block */
 887         error = ext2_htree_writebuf(&info);
 888         if (!error)
 889                 write_info = 1;
 890
 891 finish:
 892         if (dst_bp != NULL && !write_dst_bp)
 893                 brelse(dst_bp);
 894         if (bp != NULL && !write_bp)
 895                 brelse(bp);
 896         if (newdirblock != NULL)
 897                 free(newdirblock, M_TEMP);
 898         if (newidxblock != NULL)
 899                 free(newidxblock, M_TEMP);
 900         if (!write_info)
 901                 ext2_htree_release(&info);
 902         return (error);
 903 }