lustre/kernel_patches/patches/ext3-extents-2.4.24.patch

   1 Index: linux-2.4.24/fs/ext3/extents.c
   2 ===================================================================
   3 --- linux-2.4.24.orig/fs/ext3/extents.c 2003-01-30 13:24:37.000000000 +0300
   4 +++ linux-2.4.24/fs/ext3/extents.c      2004-11-03 00:36:44.894076664 +0300
   5 @@ -0,0 +1,2302 @@
   6 +/*
   7 + * Copyright(c) 2003, 2004, 2005, Cluster File Systems, Inc, info@clusterfs.com
   8 + * Written by Alex Tomas <alex@clusterfs.com>
   9 + *
  10 + * This program is free software; you can redistribute it and/or modify
  11 + * it under the terms of the GNU General Public License version 2 as
  12 + * published by the Free Software Foundation.
  13 + *
  14 + * This program is distributed in the hope that it will be useful,
  15 + * but WITHOUT ANY WARRANTY; without even the implied warranty of
  16 + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  17 + * GNU General Public License for more details.
  18 + *
  19 + * You should have received a copy of the GNU General Public Licens
  20 + * along with this program; if not, write to the Free Software
  21 + * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-
  22 + */
  23 +
  24 +/*
  25 + * Extents support for EXT3
  26 + *
  27 + * TODO:
  28 + *   - ext3_ext_walk_space() sould not use ext3_ext_find_extent()
  29 + *   - ext3_ext_calc_credits() could take 'mergable' into account
  30 + *   - ext3*_error() should be used in some situations
  31 + *   - find_goal() [to be tested and improved]
  32 + *   - smart tree reduction
  33 + *   - arch-independence
  34 + *     common on-disk format for big/little-endian arch
  35 + */
  36 +
  37 +#include <linux/module.h>
  38 +#include <linux/fs.h>
  39 +#include <linux/time.h>
  40 +#include <linux/ext3_jbd.h>
  41 +#include <linux/jbd.h>
  42 +#include <linux/locks.h>
  43 +#include <linux/smp_lock.h>
  44 +#include <linux/highuid.h>
  45 +#include <linux/pagemap.h>
  46 +#include <linux/quotaops.h>
  47 +#include <linux/string.h>
  48 +#include <linux/slab.h>
  49 +#include <linux/ext3_extents.h>
  50 +#include <asm/uaccess.h>
  51 +
  52 +
  53 +static inline int ext3_ext_check_header(struct ext3_extent_header *eh)
  54 +{
  55 +       if (eh->eh_magic != EXT3_EXT_MAGIC) {
  56 +               printk(KERN_ERR "EXT3-fs: invalid magic = 0x%x\n",
  57 +                      (unsigned)eh->eh_magic);
  58 +               return -EIO;
  59 +       }
  60 +       if (eh->eh_max == 0) {
  61 +               printk(KERN_ERR "EXT3-fs: invalid eh_max = %u\n",
  62 +                      (unsigned)eh->eh_max);
  63 +               return -EIO;
  64 +       }
  65 +       if (eh->eh_entries > eh->eh_max) {
  66 +               printk(KERN_ERR "EXT3-fs: invalid eh_entries = %u\n",
  67 +                      (unsigned)eh->eh_entries);
  68 +               return -EIO;
  69 +       }
  70 +       return 0;
  71 +}
  72 +
  73 +static handle_t *ext3_ext_journal_restart(handle_t *handle, int needed)
  74 +{
  75 +       int err;
  76 +
  77 +       if (handle->h_buffer_credits > needed)
  78 +               return handle;
  79 +       if (!ext3_journal_extend(handle, needed))
  80 +               return handle;
  81 +       err = ext3_journal_restart(handle, needed);
  82 +
  83 +       return handle;
  84 +}
  85 +
  86 +static int inline
  87 +ext3_ext_get_access_for_root(handle_t *h, struct ext3_extents_tree *tree)
  88 +{
  89 +       if (tree->ops->get_write_access)
  90 +               return tree->ops->get_write_access(h,tree->buffer);
  91 +       else
  92 +               return 0;
  93 +}
  94 +
  95 +static int inline
  96 +ext3_ext_mark_root_dirty(handle_t *h, struct ext3_extents_tree *tree)
  97 +{
  98 +       if (tree->ops->mark_buffer_dirty)
  99 +               return tree->ops->mark_buffer_dirty(h,tree->buffer);
 100 +       else
 101 +               return 0;
 102 +}
 103 +
 104 +/*
 105 + * could return:
 106 + *  - EROFS
 107 + *  - ENOMEM
 108 + */
 109 +static int ext3_ext_get_access(handle_t *handle,
 110 +                              struct ext3_extents_tree *tree,
 111 +                              struct ext3_ext_path *path)
 112 +{
 113 +       int err;
 114 +
 115 +       if (path->p_bh) {
 116 +               /* path points to block */
 117 +               err = ext3_journal_get_write_access(handle, path->p_bh);
 118 +       } else {
 119 +               /* path points to leaf/index in inode body */
 120 +               err = ext3_ext_get_access_for_root(handle, tree);
 121 +       }
 122 +       return err;
 123 +}
 124 +
 125 +/*
 126 + * could return:
 127 + *  - EROFS
 128 + *  - ENOMEM
 129 + *  - EIO
 130 + */
 131 +static int ext3_ext_dirty(handle_t *handle, struct ext3_extents_tree *tree,
 132 +                         struct ext3_ext_path *path)
 133 +{
 134 +       int err;
 135 +       if (path->p_bh) {
 136 +               /* path points to block */
 137 +               err =ext3_journal_dirty_metadata(handle, path->p_bh);
 138 +       } else {
 139 +               /* path points to leaf/index in inode body */
 140 +               err = ext3_ext_mark_root_dirty(handle, tree);
 141 +       }
 142 +       return err;
 143 +}
 144 +
 145 +static int inline
 146 +ext3_ext_new_block(handle_t *handle, struct ext3_extents_tree *tree,
 147 +                  struct ext3_ext_path *path, struct ext3_extent *ex,
 148 +                  int *err)
 149 +{
 150 +       int goal, depth, newblock;
 151 +       struct inode *inode;
 152 +
 153 +       EXT_ASSERT(tree);
 154 +       if (tree->ops->new_block)
 155 +               return tree->ops->new_block(handle, tree, path, ex, err);
 156 +
 157 +       inode = tree->inode;
 158 +       depth = EXT_DEPTH(tree);
 159 +       if (path && depth > 0) {
 160 +               goal = path[depth-1].p_block;
 161 +       } else {
 162 +               struct ext3_inode_info *ei = EXT3_I(inode);
 163 +               unsigned long bg_start;
 164 +               unsigned long colour;
 165 +
 166 +               bg_start = (ei->i_block_group *
 167 +                           EXT3_BLOCKS_PER_GROUP(inode->i_sb)) +
 168 +                       le32_to_cpu(EXT3_SB(inode->i_sb)->s_es->s_first_data_block);
 169 +               colour = (current->pid % 16) *
 170 +                       (EXT3_BLOCKS_PER_GROUP(inode->i_sb) / 16);
 171 +               goal = bg_start + colour;
 172 +       }
 173 +
 174 +       newblock = ext3_new_block(handle, inode, goal, 0, 0, err);
 175 +       return newblock;
 176 +}
 177 +
 178 +static inline void ext3_ext_tree_changed(struct ext3_extents_tree *tree)
 179 +{
 180 +       struct ext3_extent_header *neh;
 181 +       neh = EXT_ROOT_HDR(tree);
 182 +       neh->eh_generation++;
 183 +}
 184 +
 185 +static inline int ext3_ext_space_block(struct ext3_extents_tree *tree)
 186 +{
 187 +       int size;
 188 +
 189 +       size = (tree->inode->i_sb->s_blocksize -
 190 +               sizeof(struct ext3_extent_header)) /
 191 +                               sizeof(struct ext3_extent);
 192 +#ifdef AGRESSIVE_TEST
 193 +       size = 6;
 194 +#endif
 195 +       return size;
 196 +}
 197 +
 198 +static inline int ext3_ext_space_block_idx(struct ext3_extents_tree *tree)
 199 +{
 200 +       int size;
 201 +
 202 +       size = (tree->inode->i_sb->s_blocksize -
 203 +               sizeof(struct ext3_extent_header)) /
 204 +                               sizeof(struct ext3_extent_idx);
 205 +#ifdef AGRESSIVE_TEST
 206 +       size = 5;
 207 +#endif
 208 +       return size;
 209 +}
 210 +
 211 +static inline int ext3_ext_space_root(struct ext3_extents_tree *tree)
 212 +{
 213 +       int size;
 214 +
 215 +       size = (tree->buffer_len - sizeof(struct ext3_extent_header)) /
 216 +                       sizeof(struct ext3_extent);
 217 +#ifdef AGRESSIVE_TEST
 218 +       size = 3;
 219 +#endif
 220 +       return size;
 221 +}
 222 +
 223 +static inline int ext3_ext_space_root_idx(struct ext3_extents_tree *tree)
 224 +{
 225 +       int size;
 226 +
 227 +       size = (tree->buffer_len - sizeof(struct ext3_extent_header)) /
 228 +                       sizeof(struct ext3_extent_idx);
 229 +#ifdef AGRESSIVE_TEST
 230 +       size = 4;
 231 +#endif
 232 +       return size;
 233 +}
 234 +
 235 +static void ext3_ext_show_path(struct ext3_extents_tree *tree,
 236 +                              struct ext3_ext_path *path)
 237 +{
 238 +#ifdef EXT_DEBUG
 239 +       int k, l = path->p_depth;
 240 +
 241 +       ext_debug(tree, "path:");
 242 +       for (k = 0; k <= l; k++, path++) {
 243 +               if (path->p_idx) {
 244 +                       ext_debug(tree, "  %d->%d", path->p_idx->ei_block,
 245 +                                 path->p_idx->ei_leaf);
 246 +               } else if (path->p_ext) {
 247 +                       ext_debug(tree, "  %d:%d:%d",
 248 +                                 path->p_ext->ee_block,
 249 +                                 path->p_ext->ee_len,
 250 +                                 path->p_ext->ee_start);
 251 +               } else
 252 +                       ext_debug(tree, "  []");
 253 +       }
 254 +       ext_debug(tree, "\n");
 255 +#endif
 256 +}
 257 +
 258 +static void ext3_ext_show_leaf(struct ext3_extents_tree *tree,
 259 +                              struct ext3_ext_path *path)
 260 +{
 261 +#ifdef EXT_DEBUG
 262 +       int depth = EXT_DEPTH(tree);
 263 +       struct ext3_extent_header *eh;
 264 +       struct ext3_extent *ex;
 265 +       int i;
 266 +
 267 +       if (!path)
 268 +               return;
 269 +
 270 +       eh = path[depth].p_hdr;
 271 +       ex = EXT_FIRST_EXTENT(eh);
 272 +
 273 +       for (i = 0; i < eh->eh_entries; i++, ex++) {
 274 +               ext_debug(tree, "%d:%d:%d ",
 275 +                         ex->ee_block, ex->ee_len, ex->ee_start);
 276 +       }
 277 +       ext_debug(tree, "\n");
 278 +#endif
 279 +}
 280 +
 281 +static void ext3_ext_drop_refs(struct ext3_ext_path *path)
 282 +{
 283 +       int depth = path->p_depth;
 284 +       int i;
 285 +
 286 +       for (i = 0; i <= depth; i++, path++) {
 287 +               if (path->p_bh) {
 288 +                       brelse(path->p_bh);
 289 +                       path->p_bh = NULL;
 290 +               }
 291 +       }
 292 +}
 293 +
 294 +/*
 295 + * binary search for closest index by given block
 296 + */
 297 +static inline void
 298 +ext3_ext_binsearch_idx(struct ext3_extents_tree *tree,
 299 +                      struct ext3_ext_path *path, int block)
 300 +{
 301 +       struct ext3_extent_header *eh = path->p_hdr;
 302 +       struct ext3_extent_idx *ix;
 303 +       int l = 0, k, r;
 304 +
 305 +       EXT_ASSERT(eh->eh_magic == EXT3_EXT_MAGIC);
 306 +       EXT_ASSERT(eh->eh_entries <= eh->eh_max);
 307 +       EXT_ASSERT(eh->eh_entries > 0);
 308 +
 309 +       ext_debug(tree, "binsearch for %d(idx):  ", block);
 310 +
 311 +       path->p_idx = ix = EXT_FIRST_INDEX(eh);
 312 +
 313 +       r = k = eh->eh_entries;
 314 +       while (k > 1) {
 315 +               k = (r - l) / 2;
 316 +               if (block < ix[l + k].ei_block)
 317 +                       r -= k;
 318 +               else
 319 +                       l += k;
 320 +               ext_debug(tree, "%d:%d:%d ", k, l, r);
 321 +       }
 322 +
 323 +       ix += l;
 324 +       path->p_idx = ix;
 325 +       ext_debug(tree," -> %d->%d ",path->p_idx->ei_block,path->p_idx->ei_leaf);
 326 +
 327 +       while (l++ < r) {
 328 +               if (block < ix->ei_block)
 329 +                       break;
 330 +               path->p_idx = ix++;
 331 +       }
 332 +       ext_debug(tree, "  -> %d->%d\n", path->p_idx->ei_block,
 333 +                 path->p_idx->ei_leaf);
 334 +
 335 +#ifdef CHECK_BINSEARCH
 336 +       {
 337 +               struct ext3_extent_idx *chix;
 338 +
 339 +               chix = ix = EXT_FIRST_INDEX(eh);
 340 +               for (k = 0; k < eh->eh_entries; k++, ix++) {
 341 +                       if (k != 0 && ix->ei_block <= ix[-1].ei_block) {
 342 +                               printk("k=%d, ix=0x%p, first=0x%p\n", k,
 343 +                                      ix, EXT_FIRST_INDEX(eh));
 344 +                               printk("%u <= %u\n",
 345 +                                      ix->ei_block,ix[-1].ei_block);
 346 +                       }
 347 +                       EXT_ASSERT(k == 0 || ix->ei_block > ix[-1].ei_block);
 348 +                       if (block < ix->ei_block)
 349 +                               break;
 350 +                       chix = ix;
 351 +               }
 352 +               EXT_ASSERT(chix == path->p_idx);
 353 +       }
 354 +#endif
 355 +}
 356 +
 357 +/*
 358 + * binary search for closest extent by given block
 359 + */
 360 +static inline void
 361 +ext3_ext_binsearch(struct ext3_extents_tree *tree,
 362 +                  struct ext3_ext_path *path, int block)
 363 +{
 364 +       struct ext3_extent_header *eh = path->p_hdr;
 365 +       struct ext3_extent *ex;
 366 +       int l = 0, k, r;
 367 +
 368 +       EXT_ASSERT(eh->eh_magic == EXT3_EXT_MAGIC);
 369 +       EXT_ASSERT(eh->eh_entries <= eh->eh_max);
 370 +
 371 +       if (eh->eh_entries == 0) {
 372 +               /*
 373 +                * this leaf is empty yet:
 374 +                *  we get such a leaf in split/add case
 375 +                */
 376 +               return;
 377 +       }
 378 +
 379 +       ext_debug(tree, "binsearch for %d:  ", block);
 380 +
 381 +       path->p_ext = ex = EXT_FIRST_EXTENT(eh);
 382 +
 383 +       r = k = eh->eh_entries;
 384 +       while (k > 1) {
 385 +               k = (r - l) / 2;
 386 +               if (block < ex[l + k].ee_block)
 387 +                       r -= k;
 388 +               else
 389 +                       l += k;
 390 +               ext_debug(tree, "%d:%d:%d ", k, l, r);
 391 +       }
 392 +
 393 +       ex += l;
 394 +       path->p_ext = ex;
 395 +       ext_debug(tree, "  -> %d:%d:%d ", path->p_ext->ee_block,
 396 +                 path->p_ext->ee_start, path->p_ext->ee_len);
 397 +
 398 +       while (l++ < r) {
 399 +               if (block < ex->ee_block)
 400 +                       break;
 401 +               path->p_ext = ex++;
 402 +       }
 403 +       ext_debug(tree, "  -> %d:%d:%d\n", path->p_ext->ee_block,
 404 +                 path->p_ext->ee_start, path->p_ext->ee_len);
 405 +
 406 +#ifdef CHECK_BINSEARCH
 407 +       {
 408 +               struct ext3_extent *chex;
 409 +
 410 +               chex = ex = EXT_FIRST_EXTENT(eh);
 411 +               for (k = 0; k < eh->eh_entries; k++, ex++) {
 412 +                       EXT_ASSERT(k == 0 || ex->ee_block > ex[-1].ee_block);
 413 +                       if (block < ex->ee_block)
 414 +                               break;
 415 +                       chex = ex;
 416 +               }
 417 +               EXT_ASSERT(chex == path->p_ext);
 418 +       }
 419 +#endif
 420 +}
 421 +
 422 +int ext3_extent_tree_init(handle_t *handle, struct ext3_extents_tree *tree)
 423 +{
 424 +       struct ext3_extent_header *eh;
 425 +
 426 +       BUG_ON(tree->buffer_len == 0);
 427 +       ext3_ext_get_access_for_root(handle, tree);
 428 +       eh = EXT_ROOT_HDR(tree);
 429 +       eh->eh_depth = 0;
 430 +       eh->eh_entries = 0;
 431 +       eh->eh_magic = EXT3_EXT_MAGIC;
 432 +       eh->eh_max = ext3_ext_space_root(tree);
 433 +       ext3_ext_mark_root_dirty(handle, tree);
 434 +       ext3_ext_invalidate_cache(tree);
 435 +       return 0;
 436 +}
 437 +
 438 +struct ext3_ext_path *
 439 +ext3_ext_find_extent(struct ext3_extents_tree *tree, int block,
 440 +                    struct ext3_ext_path *path)
 441 +{
 442 +       struct ext3_extent_header *eh;
 443 +       struct buffer_head *bh;
 444 +       int depth, i, ppos = 0;
 445 +
 446 +       EXT_ASSERT(tree);
 447 +       EXT_ASSERT(tree->inode);
 448 +       EXT_ASSERT(tree->root);
 449 +
 450 +       eh = EXT_ROOT_HDR(tree);
 451 +       EXT_ASSERT(eh);
 452 +       if (ext3_ext_check_header(eh))
 453 +               goto err;
 454 +
 455 +       i = depth = EXT_DEPTH(tree);
 456 +       EXT_ASSERT(eh->eh_max);
 457 +       EXT_ASSERT(eh->eh_magic == EXT3_EXT_MAGIC);
 458 +
 459 +       /* account possible depth increase */
 460 +       if (!path) {
 461 +               path = kmalloc(sizeof(struct ext3_ext_path) * (depth + 2),
 462 +                              GFP_NOFS);
 463 +               if (!path)
 464 +                       return ERR_PTR(-ENOMEM);
 465 +       }
 466 +       memset(path, 0, sizeof(struct ext3_ext_path) * (depth + 1));
 467 +       path[0].p_hdr = eh;
 468 +
 469 +       /* walk through the tree */
 470 +       while (i) {
 471 +               ext_debug(tree, "depth %d: num %d, max %d\n",
 472 +                         ppos, eh->eh_entries, eh->eh_max);
 473 +               ext3_ext_binsearch_idx(tree, path + ppos, block);
 474 +               path[ppos].p_block = path[ppos].p_idx->ei_leaf;
 475 +               path[ppos].p_depth = i;
 476 +               path[ppos].p_ext = NULL;
 477 +
 478 +               bh = sb_bread(tree->inode->i_sb, path[ppos].p_block);
 479 +               if (!bh)
 480 +                       goto err;
 481 +               eh = EXT_BLOCK_HDR(bh);
 482 +               ppos++;
 483 +               EXT_ASSERT(ppos <= depth);
 484 +               path[ppos].p_bh = bh;
 485 +               path[ppos].p_hdr = eh;
 486 +               i--;
 487 +
 488 +               if (ext3_ext_check_header(eh))
 489 +                       goto err;
 490 +       }
 491 +
 492 +       path[ppos].p_depth = i;
 493 +       path[ppos].p_hdr = eh;
 494 +       path[ppos].p_ext = NULL;
 495 +       path[ppos].p_idx = NULL;
 496 +
 497 +       if (ext3_ext_check_header(eh))
 498 +               goto err;
 499 +
 500 +       /* find extent */
 501 +       ext3_ext_binsearch(tree, path + ppos, block);
 502 +
 503 +       ext3_ext_show_path(tree, path);
 504 +
 505 +       return path;
 506 +
 507 +err:
 508 +       printk(KERN_ERR "EXT3-fs: header is corrupted!\n");
 509 +       ext3_ext_drop_refs(path);
 510 +       kfree(path);
 511 +       return ERR_PTR(-EIO);
 512 +}
 513 +
 514 +/*
 515 + * insert new index [logical;ptr] into the block at cupr
 516 + * it check where to insert: before curp or after curp
 517 + */
 518 +static int ext3_ext_insert_index(handle_t *handle,
 519 +                                struct ext3_extents_tree *tree,
 520 +                                struct ext3_ext_path *curp,
 521 +                                int logical, int ptr)
 522 +{
 523 +       struct ext3_extent_idx *ix;
 524 +       int len, err;
 525 +
 526 +       if ((err = ext3_ext_get_access(handle, tree, curp)))
 527 +               return err;
 528 +
 529 +       EXT_ASSERT(logical != curp->p_idx->ei_block);
 530 +       len = EXT_MAX_INDEX(curp->p_hdr) - curp->p_idx;
 531 +       if (logical > curp->p_idx->ei_block) {
 532 +               /* insert after */
 533 +               if (curp->p_idx != EXT_LAST_INDEX(curp->p_hdr)) {
 534 +                       len = (len - 1) * sizeof(struct ext3_extent_idx);
 535 +                       len = len < 0 ? 0 : len;
 536 +                       ext_debug(tree, "insert new index %d after: %d. "
 537 +                                 "move %d from 0x%p to 0x%p\n",
 538 +                                 logical, ptr, len,
 539 +                                 (curp->p_idx + 1), (curp->p_idx + 2));
 540 +                       memmove(curp->p_idx + 2, curp->p_idx + 1, len);
 541 +               }
 542 +               ix = curp->p_idx + 1;
 543 +       } else {
 544 +               /* insert before */
 545 +               len = len * sizeof(struct ext3_extent_idx);
 546 +               len = len < 0 ? 0 : len;
 547 +               ext_debug(tree, "insert new index %d before: %d. "
 548 +                         "move %d from 0x%p to 0x%p\n",
 549 +                         logical, ptr, len,
 550 +                         curp->p_idx, (curp->p_idx + 1));
 551 +               memmove(curp->p_idx + 1, curp->p_idx, len);
 552 +               ix = curp->p_idx;
 553 +       }
 554 +
 555 +       ix->ei_block = logical;
 556 +       ix->ei_leaf = ptr;
 557 +       curp->p_hdr->eh_entries++;
 558 +
 559 +       EXT_ASSERT(curp->p_hdr->eh_entries <= curp->p_hdr->eh_max);
 560 +       EXT_ASSERT(ix <= EXT_LAST_INDEX(curp->p_hdr));
 561 +
 562 +       err = ext3_ext_dirty(handle, tree, curp);
 563 +       ext3_std_error(tree->inode->i_sb, err);
 564 +
 565 +       return err;
 566 +}
 567 +
 568 +/*
 569 + * routine inserts new subtree into the path, using free index entry
 570 + * at depth 'at:
 571 + *  - allocates all needed blocks (new leaf and all intermediate index blocks)
 572 + *  - makes decision where to split
 573 + *  - moves remaining extens and index entries (right to the split point)
 574 + *    into the newly allocated blocks
 575 + *  - initialize subtree
 576 + */
 577 +static int ext3_ext_split(handle_t *handle, struct ext3_extents_tree *tree,
 578 +                         struct ext3_ext_path *path,
 579 +                         struct ext3_extent *newext, int at)
 580 +{
 581 +       struct buffer_head *bh = NULL;
 582 +       int depth = EXT_DEPTH(tree);
 583 +       struct ext3_extent_header *neh;
 584 +       struct ext3_extent_idx *fidx;
 585 +       struct ext3_extent *ex;
 586 +       int i = at, k, m, a;
 587 +       unsigned long newblock, oldblock, border;
 588 +       int *ablocks = NULL; /* array of allocated blocks */
 589 +       int err = 0;
 590 +
 591 +       /* make decision: where to split? */
 592 +       /* FIXME: now desicion is simplest: at current extent */
 593 +
 594 +       /* if current leaf will be splitted, then we should use
 595 +        * border from split point */
 596 +       EXT_ASSERT(path[depth].p_ext <= EXT_MAX_EXTENT(path[depth].p_hdr));
 597 +       if (path[depth].p_ext != EXT_MAX_EXTENT(path[depth].p_hdr)) {
 598 +               border = path[depth].p_ext[1].ee_block;
 599 +               ext_debug(tree, "leaf will be splitted."
 600 +                         " next leaf starts at %d\n",
 601 +                         (int)border);
 602 +       } else {
 603 +               border = newext->ee_block;
 604 +               ext_debug(tree, "leaf will be added."
 605 +                         " next leaf starts at %d\n",
 606 +                         (int)border);
 607 +       }
 608 +
 609 +       /*
 610 +        * if error occurs, then we break processing
 611 +        * and turn filesystem read-only. so, index won't
 612 +        * be inserted and tree will be in consistent
 613 +        * state. next mount will repair buffers too
 614 +        */
 615 +
 616 +       /*
 617 +        * get array to track all allocated blocks
 618 +        * we need this to handle errors and free blocks
 619 +        * upon them
 620 +        */
 621 +       ablocks = kmalloc(sizeof(unsigned long) * depth, GFP_NOFS);
 622 +       if (!ablocks)
 623 +               return -ENOMEM;
 624 +       memset(ablocks, 0, sizeof(unsigned long) * depth);
 625 +
 626 +       /* allocate all needed blocks */
 627 +       ext_debug(tree, "allocate %d blocks for indexes/leaf\n", depth - at);
 628 +       for (a = 0; a < depth - at; a++) {
 629 +               newblock = ext3_ext_new_block(handle, tree, path, newext, &err);
 630 +               if (newblock == 0)
 631 +                       goto cleanup;
 632 +               ablocks[a] = newblock;
 633 +       }
 634 +
 635 +       /* initialize new leaf */
 636 +       newblock = ablocks[--a];
 637 +       EXT_ASSERT(newblock);
 638 +       bh = sb_getblk(tree->inode->i_sb, newblock);
 639 +       if (!bh) {
 640 +               err = -EIO;
 641 +               goto cleanup;
 642 +       }
 643 +       lock_buffer(bh);
 644 +
 645 +       if ((err = ext3_journal_get_create_access(handle, bh)))
 646 +               goto cleanup;
 647 +
 648 +       neh = EXT_BLOCK_HDR(bh);
 649 +       neh->eh_entries = 0;
 650 +       neh->eh_max = ext3_ext_space_block(tree);
 651 +       neh->eh_magic = EXT3_EXT_MAGIC;
 652 +       neh->eh_depth = 0;
 653 +       ex = EXT_FIRST_EXTENT(neh);
 654 +
 655 +       /* move remain of path[depth] to the new leaf */
 656 +       EXT_ASSERT(path[depth].p_hdr->eh_entries == path[depth].p_hdr->eh_max);
 657 +       /* start copy from next extent */
 658 +       /* TODO: we could do it by single memmove */
 659 +       m = 0;
 660 +       path[depth].p_ext++;
 661 +       while (path[depth].p_ext <=
 662 +                       EXT_MAX_EXTENT(path[depth].p_hdr)) {
 663 +               ext_debug(tree, "move %d:%d:%d in new leaf %lu\n",
 664 +                         path[depth].p_ext->ee_block,
 665 +                         path[depth].p_ext->ee_start,
 666 +                         path[depth].p_ext->ee_len,
 667 +                         newblock);
 668 +               memmove(ex++, path[depth].p_ext++, sizeof(struct ext3_extent));
 669 +               neh->eh_entries++;
 670 +               m++;
 671 +       }
 672 +       mark_buffer_uptodate(bh, 1);
 673 +       unlock_buffer(bh);
 674 +
 675 +       if ((err = ext3_journal_dirty_metadata(handle, bh)))
 676 +               goto cleanup;
 677 +       brelse(bh);
 678 +       bh = NULL;
 679 +
 680 +       /* correct old leaf */
 681 +       if (m) {
 682 +               if ((err = ext3_ext_get_access(handle, tree, path + depth)))
 683 +                       goto cleanup;
 684 +               path[depth].p_hdr->eh_entries -= m;
 685 +               if ((err = ext3_ext_dirty(handle, tree, path + depth)))
 686 +                       goto cleanup;
 687 +
 688 +       }
 689 +
 690 +       /* create intermediate indexes */
 691 +       k = depth - at - 1;
 692 +       EXT_ASSERT(k >= 0);
 693 +       if (k)
 694 +               ext_debug(tree, "create %d intermediate indices\n", k);
 695 +       /* insert new index into current index block */
 696 +       /* current depth stored in i var */
 697 +       i = depth - 1;
 698 +       while (k--) {
 699 +               oldblock = newblock;
 700 +               newblock = ablocks[--a];
 701 +               bh = sb_getblk(tree->inode->i_sb, newblock);
 702 +               if (!bh) {
 703 +                       err = -EIO;
 704 +                       goto cleanup;
 705 +               }
 706 +               lock_buffer(bh);
 707 +
 708 +               if ((err = ext3_journal_get_create_access(handle, bh)))
 709 +                       goto cleanup;
 710 +
 711 +               neh = EXT_BLOCK_HDR(bh);
 712 +               neh->eh_entries = 1;
 713 +               neh->eh_magic = EXT3_EXT_MAGIC;
 714 +               neh->eh_max = ext3_ext_space_block_idx(tree);
 715 +               neh->eh_depth = depth - i;
 716 +               fidx = EXT_FIRST_INDEX(neh);
 717 +               fidx->ei_block = border;
 718 +               fidx->ei_leaf = oldblock;
 719 +
 720 +               ext_debug(tree, "int.index at %d (block %lu): %lu -> %lu\n",
 721 +                         i, newblock, border, oldblock);
 722 +               /* copy indexes */
 723 +               m = 0;
 724 +               path[i].p_idx++;
 725 +
 726 +               ext_debug(tree, "cur 0x%p, last 0x%p\n", path[i].p_idx,
 727 +                         EXT_MAX_INDEX(path[i].p_hdr));
 728 +               EXT_ASSERT(EXT_MAX_INDEX(path[i].p_hdr) ==
 729 +                          EXT_LAST_INDEX(path[i].p_hdr));
 730 +               while (path[i].p_idx <= EXT_MAX_INDEX(path[i].p_hdr)) {
 731 +                       ext_debug(tree, "%d: move %d:%d in new index %lu\n",
 732 +                                 i, path[i].p_idx->ei_block,
 733 +                                 path[i].p_idx->ei_leaf, newblock);
 734 +                       memmove(++fidx, path[i].p_idx++,
 735 +                               sizeof(struct ext3_extent_idx));
 736 +                       neh->eh_entries++;
 737 +                       EXT_ASSERT(neh->eh_entries <= neh->eh_max);
 738 +                       m++;
 739 +               }
 740 +               mark_buffer_uptodate(bh, 1);
 741 +               unlock_buffer(bh);
 742 +
 743 +               if ((err = ext3_journal_dirty_metadata(handle, bh)))
 744 +                       goto cleanup;
 745 +               brelse(bh);
 746 +               bh = NULL;
 747 +
 748 +               /* correct old index */
 749 +               if (m) {
 750 +                       err = ext3_ext_get_access(handle, tree, path + i);
 751 +                       if (err)
 752 +                               goto cleanup;
 753 +                       path[i].p_hdr->eh_entries -= m;
 754 +                       err = ext3_ext_dirty(handle, tree, path + i);
 755 +                       if (err)
 756 +                               goto cleanup;
 757 +               }
 758 +
 759 +               i--;
 760 +       }
 761 +
 762 +       /* insert new index */
 763 +       if (!err)
 764 +               err = ext3_ext_insert_index(handle, tree, path + at,
 765 +                                           border, newblock);
 766 +
 767 +cleanup:
 768 +       if (bh) {
 769 +               if (buffer_locked(bh))
 770 +                       unlock_buffer(bh);
 771 +               brelse(bh);
 772 +       }
 773 +
 774 +       if (err) {
 775 +               /* free all allocated blocks in error case */
 776 +               for (i = 0; i < depth; i++) {
 777 +                       if (!ablocks[i])
 778 +                               continue;
 779 +                       ext3_free_blocks(handle, tree->inode, ablocks[i], 1);
 780 +               }
 781 +       }
 782 +       kfree(ablocks);
 783 +
 784 +       return err;
 785 +}
 786 +
 787 +/*
 788 + * routine implements tree growing procedure:
 789 + *  - allocates new block
 790 + *  - moves top-level data (index block or leaf) into the new block
 791 + *  - initialize new top-level, creating index that points to the
 792 + *    just created block
 793 + */
 794 +static int ext3_ext_grow_indepth(handle_t *handle,
 795 +                                struct ext3_extents_tree *tree,
 796 +                                struct ext3_ext_path *path,
 797 +                                struct ext3_extent *newext)
 798 +{
 799 +       struct ext3_ext_path *curp = path;
 800 +       struct ext3_extent_header *neh;
 801 +       struct ext3_extent_idx *fidx;
 802 +       struct buffer_head *bh;
 803 +       unsigned long newblock;
 804 +       int err = 0;
 805 +
 806 +       newblock = ext3_ext_new_block(handle, tree, path, newext, &err);
 807 +       if (newblock == 0)
 808 +               return err;
 809 +
 810 +       bh = sb_getblk(tree->inode->i_sb, newblock);
 811 +       if (!bh) {
 812 +               err = -EIO;
 813 +               ext3_std_error(tree->inode->i_sb, err);
 814 +               return err;
 815 +       }
 816 +       lock_buffer(bh);
 817 +
 818 +       if ((err = ext3_journal_get_create_access(handle, bh))) {
 819 +               unlock_buffer(bh);
 820 +               goto out;
 821 +       }
 822 +
 823 +       /* move top-level index/leaf into new block */
 824 +       memmove(bh->b_data, curp->p_hdr, tree->buffer_len);
 825 +
 826 +       /* set size of new block */
 827 +       neh = EXT_BLOCK_HDR(bh);
 828 +       /* old root could have indexes or leaves
 829 +        * so calculate eh_max right way */
 830 +       if (EXT_DEPTH(tree))
 831 +               neh->eh_max = ext3_ext_space_block_idx(tree);
 832 +       else
 833 +               neh->eh_max = ext3_ext_space_block(tree);
 834 +       neh->eh_magic = EXT3_EXT_MAGIC;
 835 +       mark_buffer_uptodate(bh, 1);
 836 +       unlock_buffer(bh);
 837 +
 838 +       if ((err = ext3_journal_dirty_metadata(handle, bh)))
 839 +               goto out;
 840 +
 841 +       /* create index in new top-level index: num,max,pointer */
 842 +       if ((err = ext3_ext_get_access(handle, tree, curp)))
 843 +               goto out;
 844 +
 845 +       curp->p_hdr->eh_magic = EXT3_EXT_MAGIC;
 846 +       curp->p_hdr->eh_max = ext3_ext_space_root_idx(tree);
 847 +       curp->p_hdr->eh_entries = 1;
 848 +       curp->p_idx = EXT_FIRST_INDEX(curp->p_hdr);
 849 +       /* FIXME: it works, but actually path[0] can be index */
 850 +       curp->p_idx->ei_block = EXT_FIRST_EXTENT(path[0].p_hdr)->ee_block;
 851 +       curp->p_idx->ei_leaf = newblock;
 852 +
 853 +       neh = EXT_ROOT_HDR(tree);
 854 +       fidx = EXT_FIRST_INDEX(neh);
 855 +       ext_debug(tree, "new root: num %d(%d), lblock %d, ptr %d\n",
 856 +                 neh->eh_entries, neh->eh_max, fidx->ei_block, fidx->ei_leaf);
 857 +
 858 +       neh->eh_depth = path->p_depth + 1;
 859 +       err = ext3_ext_dirty(handle, tree, curp);
 860 +out:
 861 +       brelse(bh);
 862 +
 863 +       return err;
 864 +}
 865 +
 866 +/*
 867 + * routine finds empty index and adds new leaf. if no free index found
 868 + * then it requests in-depth growing
 869 + */
 870 +static int ext3_ext_create_new_leaf(handle_t *handle,
 871 +                                   struct ext3_extents_tree *tree,
 872 +                                   struct ext3_ext_path *path,
 873 +                                   struct ext3_extent *newext)
 874 +{
 875 +       struct ext3_ext_path *curp;
 876 +       int depth, i, err = 0;
 877 +
 878 +repeat:
 879 +       i = depth = EXT_DEPTH(tree);
 880 +
 881 +       /* walk up to the tree and look for free index entry */
 882 +       curp = path + depth;
 883 +       while (i > 0 && !EXT_HAS_FREE_INDEX(curp)) {
 884 +               i--;
 885 +               curp--;
 886 +       }
 887 +
 888 +       /* we use already allocated block for index block
 889 +        * so, subsequent data blocks should be contigoues */
 890 +       if (EXT_HAS_FREE_INDEX(curp)) {
 891 +               /* if we found index with free entry, then use that
 892 +                * entry: create all needed subtree and add new leaf */
 893 +               err = ext3_ext_split(handle, tree, path, newext, i);
 894 +
 895 +               /* refill path */
 896 +               ext3_ext_drop_refs(path);
 897 +               path = ext3_ext_find_extent(tree, newext->ee_block, path);
 898 +               if (IS_ERR(path))
 899 +                       err = PTR_ERR(path);
 900 +       } else {
 901 +               /* tree is full, time to grow in depth */
 902 +               err = ext3_ext_grow_indepth(handle, tree, path, newext);
 903 +
 904 +               /* refill path */
 905 +               ext3_ext_drop_refs(path);
 906 +               path = ext3_ext_find_extent(tree, newext->ee_block, path);
 907 +               if (IS_ERR(path))
 908 +                       err = PTR_ERR(path);
 909 +
 910 +               /*
 911 +                * only first (depth 0 -> 1) produces free space
 912 +                * in all other cases we have to split growed tree
 913 +                */
 914 +               depth = EXT_DEPTH(tree);
 915 +               if (path[depth].p_hdr->eh_entries == path[depth].p_hdr->eh_max) {
 916 +                       /* now we need split */
 917 +                       goto repeat;
 918 +               }
 919 +       }
 920 +
 921 +       if (err)
 922 +               return err;
 923 +
 924 +       return 0;
 925 +}
 926 +
 927 +/*
 928 + * returns allocated block in subsequent extent or EXT_MAX_BLOCK
 929 + * NOTE: it consider block number from index entry as
 930 + * allocated block. thus, index entries have to be consistent
 931 + * with leafs
 932 + */
 933 +static unsigned long
 934 +ext3_ext_next_allocated_block(struct ext3_ext_path *path)
 935 +{
 936 +       int depth;
 937 +
 938 +       EXT_ASSERT(path != NULL);
 939 +       depth = path->p_depth;
 940 +
 941 +       if (depth == 0 && path->p_ext == NULL)
 942 +               return EXT_MAX_BLOCK;
 943 +
 944 +       /* FIXME: what if index isn't full ?! */
 945 +       while (depth >= 0) {
 946 +               if (depth == path->p_depth) {
 947 +                       /* leaf */
 948 +                       if (path[depth].p_ext !=
 949 +                           EXT_LAST_EXTENT(path[depth].p_hdr))
 950 +                               return path[depth].p_ext[1].ee_block;
 951 +               } else {
 952 +                       /* index */
 953 +                       if (path[depth].p_idx !=
 954 +                           EXT_LAST_INDEX(path[depth].p_hdr))
 955 +                               return path[depth].p_idx[1].ei_block;
 956 +               }
 957 +               depth--;
 958 +       }
 959 +
 960 +       return EXT_MAX_BLOCK;
 961 +}
 962 +
 963 +/*
 964 + * returns first allocated block from next leaf or EXT_MAX_BLOCK
 965 + */
 966 +static unsigned ext3_ext_next_leaf_block(struct ext3_extents_tree *tree,
 967 +                                        struct ext3_ext_path *path)
 968 +{
 969 +       int depth;
 970 +
 971 +       EXT_ASSERT(path != NULL);
 972 +       depth = path->p_depth;
 973 +
 974 +       /* zero-tree has no leaf blocks at all */
 975 +       if (depth == 0)
 976 +               return EXT_MAX_BLOCK;
 977 +
 978 +       /* go to index block */
 979 +       depth--;
 980 +
 981 +       while (depth >= 0) {
 982 +               if (path[depth].p_idx !=
 983 +                   EXT_LAST_INDEX(path[depth].p_hdr))
 984 +                       return path[depth].p_idx[1].ei_block;
 985 +               depth--;
 986 +       }
 987 +
 988 +       return EXT_MAX_BLOCK;
 989 +}
 990 +
 991 +/*
 992 + * if leaf gets modified and modified extent is first in the leaf
 993 + * then we have to correct all indexes above
 994 + * TODO: do we need to correct tree in all cases?
 995 + */
 996 +int ext3_ext_correct_indexes(handle_t *handle, struct ext3_extents_tree *tree,
 997 +                            struct ext3_ext_path *path)
 998 +{
 999 +       struct ext3_extent_header *eh;
1000 +       int depth = EXT_DEPTH(tree);
1001 +       struct ext3_extent *ex;
1002 +       unsigned long border;
1003 +       int k, err = 0;
1004 +
1005 +       eh = path[depth].p_hdr;
1006 +       ex = path[depth].p_ext;
1007 +       EXT_ASSERT(ex);
1008 +       EXT_ASSERT(eh);
1009 +
1010 +       if (depth == 0) {
1011 +               /* there is no tree at all */
1012 +               return 0;
1013 +       }
1014 +
1015 +       if (ex != EXT_FIRST_EXTENT(eh)) {
1016 +               /* we correct tree if first leaf got modified only */
1017 +               return 0;
1018 +       }
1019 +
1020 +       /*
1021 +        * TODO: we need correction if border is smaller then current one
1022 +        */
1023 +       k = depth - 1;
1024 +       border = path[depth].p_ext->ee_block;
1025 +       if ((err = ext3_ext_get_access(handle, tree, path + k)))
1026 +               return err;
1027 +       path[k].p_idx->ei_block = border;
1028 +       if ((err = ext3_ext_dirty(handle, tree, path + k)))
1029 +               return err;
1030 +
1031 +       while (k--) {
1032 +               /* change all left-side indexes */
1033 +               if (path[k+1].p_idx != EXT_FIRST_INDEX(path[k+1].p_hdr))
1034 +                       break;
1035 +               if ((err = ext3_ext_get_access(handle, tree, path + k)))
1036 +                       break;
1037 +               path[k].p_idx->ei_block = border;
1038 +               if ((err = ext3_ext_dirty(handle, tree, path + k)))
1039 +                       break;
1040 +       }
1041 +
1042 +       return err;
1043 +}
1044 +
1045 +static int inline
1046 +ext3_can_extents_be_merged(struct ext3_extents_tree *tree,
1047 +                          struct ext3_extent *ex1,
1048 +                          struct ext3_extent *ex2)
1049 +{
1050 +       if (ex1->ee_block + ex1->ee_len != ex2->ee_block)
1051 +               return 0;
1052 +
1053 +#ifdef AGRESSIVE_TEST
1054 +       if (ex1->ee_len >= 4)
1055 +               return 0;
1056 +#endif
1057 +
1058 +       if (!tree->ops->mergable)
1059 +               return 1;
1060 +
1061 +       return tree->ops->mergable(ex1, ex2);
1062 +}
1063 +
1064 +/*
1065 + * this routine tries to merge requsted extent into the existing
1066 + * extent or inserts requested extent as new one into the tree,
1067 + * creating new leaf in no-space case
1068 + */
1069 +int ext3_ext_insert_extent(handle_t *handle, struct ext3_extents_tree *tree,
1070 +                          struct ext3_ext_path *path,
1071 +                          struct ext3_extent *newext)
1072 +{
1073 +       struct ext3_extent_header * eh;
1074 +       struct ext3_extent *ex, *fex;
1075 +       struct ext3_extent *nearex; /* nearest extent */
1076 +       struct ext3_ext_path *npath = NULL;
1077 +       int depth, len, err, next;
1078 +
1079 +       EXT_ASSERT(newext->ee_len > 0);
1080 +       depth = EXT_DEPTH(tree);
1081 +       ex = path[depth].p_ext;
1082 +       EXT_ASSERT(path[depth].p_hdr);
1083 +
1084 +       /* try to insert block into found extent and return */
1085 +       if (ex && ext3_can_extents_be_merged(tree, ex, newext)) {
1086 +               ext_debug(tree, "append %d block to %d:%d (from %d)\n",
1087 +                         newext->ee_len, ex->ee_block, ex->ee_len,
1088 +                         ex->ee_start);
1089 +               if ((err = ext3_ext_get_access(handle, tree, path + depth)))
1090 +                       return err;
1091 +               ex->ee_len += newext->ee_len;
1092 +               eh = path[depth].p_hdr;
1093 +               nearex = ex;
1094 +               goto merge;
1095 +       }
1096 +
1097 +repeat:
1098 +       depth = EXT_DEPTH(tree);
1099 +       eh = path[depth].p_hdr;
1100 +       if (eh->eh_entries < eh->eh_max)
1101 +               goto has_space;
1102 +
1103 +       /* probably next leaf has space for us? */
1104 +       fex = EXT_LAST_EXTENT(eh);
1105 +       next = ext3_ext_next_leaf_block(tree, path);
1106 +       if (newext->ee_block > fex->ee_block && next != EXT_MAX_BLOCK) {
1107 +               ext_debug(tree, "next leaf block - %d\n", next);
1108 +               EXT_ASSERT(!npath);
1109 +               npath = ext3_ext_find_extent(tree, next, NULL);
1110 +               if (IS_ERR(npath))
1111 +                       return PTR_ERR(npath);
1112 +               EXT_ASSERT(npath->p_depth == path->p_depth);
1113 +               eh = npath[depth].p_hdr;
1114 +               if (eh->eh_entries < eh->eh_max) {
1115 +                       ext_debug(tree, "next leaf isnt full(%d)\n",
1116 +                                 eh->eh_entries);
1117 +                       path = npath;
1118 +                       goto repeat;
1119 +               }
1120 +               ext_debug(tree, "next leaf hasno free space(%d,%d)\n",
1121 +                         eh->eh_entries, eh->eh_max);
1122 +       }
1123 +
1124 +       /*
1125 +        * there is no free space in found leaf
1126 +        * we're gonna add new leaf in the tree
1127 +        */
1128 +       err = ext3_ext_create_new_leaf(handle, tree, path, newext);
1129 +       if (err)
1130 +               goto cleanup;
1131 +       depth = EXT_DEPTH(tree);
1132 +       eh = path[depth].p_hdr;
1133 +
1134 +has_space:
1135 +       nearex = path[depth].p_ext;
1136 +
1137 +       if ((err = ext3_ext_get_access(handle, tree, path + depth)))
1138 +               goto cleanup;
1139 +
1140 +       if (!nearex) {
1141 +               /* there is no extent in this leaf, create first one */
1142 +               ext_debug(tree, "first extent in the leaf: %d:%d:%d\n",
1143 +                         newext->ee_block, newext->ee_start,
1144 +                         newext->ee_len);
1145 +               path[depth].p_ext = EXT_FIRST_EXTENT(eh);
1146 +       } else if (newext->ee_block > nearex->ee_block) {
1147 +               EXT_ASSERT(newext->ee_block != nearex->ee_block);
1148 +               if (nearex != EXT_LAST_EXTENT(eh)) {
1149 +                       len = EXT_MAX_EXTENT(eh) - nearex;
1150 +                       len = (len - 1) * sizeof(struct ext3_extent);
1151 +                       len = len < 0 ? 0 : len;
1152 +                       ext_debug(tree, "insert %d:%d:%d after: nearest 0x%p, "
1153 +                                 "move %d from 0x%p to 0x%p\n",
1154 +                                 newext->ee_block, newext->ee_start,
1155 +                                 newext->ee_len,
1156 +                                 nearex, len, nearex + 1, nearex + 2);
1157 +                       memmove(nearex + 2, nearex + 1, len);
1158 +               }
1159 +               path[depth].p_ext = nearex + 1;
1160 +       } else {
1161 +               EXT_ASSERT(newext->ee_block != nearex->ee_block);
1162 +               len = (EXT_MAX_EXTENT(eh) - nearex) * sizeof(struct ext3_extent);
1163 +               len = len < 0 ? 0 : len;
1164 +               ext_debug(tree, "insert %d:%d:%d before: nearest 0x%p, "
1165 +                         "move %d from 0x%p to 0x%p\n",
1166 +                         newext->ee_block, newext->ee_start, newext->ee_len,
1167 +                         nearex, len, nearex + 1, nearex + 2);
1168 +               memmove(nearex + 1, nearex, len);
1169 +               path[depth].p_ext = nearex;
1170 +       }
1171 +
1172 +       eh->eh_entries++;
1173 +       nearex = path[depth].p_ext;
1174 +       nearex->ee_block = newext->ee_block;
1175 +       nearex->ee_start = newext->ee_start;
1176 +       nearex->ee_len = newext->ee_len;
1177 +       /* FIXME: support for large fs */
1178 +       nearex->ee_start_hi = 0;
1179 +
1180 +merge:
1181 +       /* try to merge extents to the right */
1182 +       while (nearex < EXT_LAST_EXTENT(eh)) {
1183 +               if (!ext3_can_extents_be_merged(tree, nearex, nearex + 1))
1184 +                       break;
1185 +               /* merge with next extent! */
1186 +               nearex->ee_len += nearex[1].ee_len;
1187 +               if (nearex + 1 < EXT_LAST_EXTENT(eh)) {
1188 +                       len = (EXT_LAST_EXTENT(eh) - nearex - 1) *
1189 +                               sizeof(struct ext3_extent);
1190 +                       memmove(nearex + 1, nearex + 2, len);
1191 +               }
1192 +               eh->eh_entries--;
1193 +               EXT_ASSERT(eh->eh_entries > 0);
1194 +       }
1195 +
1196 +       /* try to merge extents to the left */
1197 +
1198 +       /* time to correct all indexes above */
1199 +       err = ext3_ext_correct_indexes(handle, tree, path);
1200 +       if (err)
1201 +               goto cleanup;
1202 +
1203 +       err = ext3_ext_dirty(handle, tree, path + depth);
1204 +
1205 +cleanup:
1206 +       if (npath) {
1207 +               ext3_ext_drop_refs(npath);
1208 +               kfree(npath);
1209 +       }
1210 +       ext3_ext_tree_changed(tree);
1211 +       ext3_ext_invalidate_cache(tree);
1212 +       return err;
1213 +}
1214 +
1215 +int ext3_ext_walk_space(struct ext3_extents_tree *tree, unsigned long block,
1216 +                       unsigned long num, ext_prepare_callback func)
1217 +{
1218 +       struct ext3_ext_path *path = NULL;
1219 +       struct ext3_ext_cache cbex;
1220 +       struct ext3_extent *ex;
1221 +       unsigned long next, start = 0, end = 0;
1222 +       unsigned long last = block + num;
1223 +       int depth, exists, err = 0;
1224 +
1225 +       EXT_ASSERT(tree);
1226 +       EXT_ASSERT(func);
1227 +       EXT_ASSERT(tree->inode);
1228 +       EXT_ASSERT(tree->root);
1229 +
1230 +       while (block < last && block != EXT_MAX_BLOCK) {
1231 +               num = last - block;
1232 +               /* find extent for this block */
1233 +               path = ext3_ext_find_extent(tree, block, path);
1234 +               if (IS_ERR(path)) {
1235 +                       err = PTR_ERR(path);
1236 +                       path = NULL;
1237 +                       break;
1238 +               }
1239 +
1240 +               depth = EXT_DEPTH(tree);
1241 +               EXT_ASSERT(path[depth].p_hdr);
1242 +               ex = path[depth].p_ext;
1243 +               next = ext3_ext_next_allocated_block(path);
1244 +
1245 +               exists = 0;
1246 +               if (!ex) {
1247 +                       /* there is no extent yet, so try to allocate
1248 +                        * all requested space */
1249 +                       start = block;
1250 +                       end = block + num;
1251 +               } else if (ex->ee_block > block) {
1252 +                       /* need to allocate space before found extent */
1253 +                       start = block;
1254 +                       end = ex->ee_block;
1255 +                       if (block + num < end)
1256 +                               end = block + num;
1257 +               } else if (block >= ex->ee_block + ex->ee_len) {
1258 +                       /* need to allocate space after found extent */
1259 +                       start = block;
1260 +                       end = block + num;
1261 +                       if (end >= next)
1262 +                               end = next;
1263 +               } else if (block >= ex->ee_block) {
1264 +                       /*
1265 +                        * some part of requested space is covered
1266 +                        * by found extent
1267 +                        */
1268 +                       start = block;
1269 +                       end = ex->ee_block + ex->ee_len;
1270 +                       if (block + num < end)
1271 +                               end = block + num;
1272 +                       exists = 1;
1273 +               } else {
1274 +                       BUG();
1275 +               }
1276 +               EXT_ASSERT(end > start);
1277 +
1278 +               if (!exists) {
1279 +                       cbex.ec_block = start;
1280 +                       cbex.ec_len = end - start;
1281 +                       cbex.ec_start = 0;
1282 +                       cbex.ec_type = EXT3_EXT_CACHE_GAP;
1283 +               } else {
1284 +                       cbex.ec_block = ex->ee_block;
1285 +                       cbex.ec_len = ex->ee_len;
1286 +                       cbex.ec_start = ex->ee_start;
1287 +                       cbex.ec_type = EXT3_EXT_CACHE_EXTENT;
1288 +               }
1289 +
1290 +               EXT_ASSERT(cbex.ec_len > 0);
1291 +               EXT_ASSERT(path[depth].p_hdr);
1292 +               err = func(tree, path, &cbex);
1293 +               ext3_ext_drop_refs(path);
1294 +
1295 +               if (err < 0)
1296 +                       break;
1297 +               if (err == EXT_REPEAT)
1298 +                       continue;
1299 +               else if (err == EXT_BREAK) {
1300 +                       err = 0;
1301 +                       break;
1302 +               }
1303 +
1304 +               if (EXT_DEPTH(tree) != depth) {
1305 +                       /* depth was changed. we have to realloc path */
1306 +                       kfree(path);
1307 +                       path = NULL;
1308 +               }
1309 +
1310 +               block = cbex.ec_block + cbex.ec_len;
1311 +       }
1312 +
1313 +       if (path) {
1314 +               ext3_ext_drop_refs(path);
1315 +               kfree(path);
1316 +       }
1317 +
1318 +       return err;
1319 +}
1320 +
1321 +static inline void
1322 +ext3_ext_put_in_cache(struct ext3_extents_tree *tree, __u32 block,
1323 +                     __u32 len, __u32 start, int type)
1324 +{
1325 +       EXT_ASSERT(len > 0);
1326 +       if (tree->cex) {
1327 +               tree->cex->ec_type = type;
1328 +               tree->cex->ec_block = block;
1329 +               tree->cex->ec_len = len;
1330 +               tree->cex->ec_start = start;
1331 +       }
1332 +}
1333 +
1334 +/*
1335 + * this routine calculate boundaries of the gap requested block fits into
1336 + * and cache this gap
1337 + */
1338 +static inline void
1339 +ext3_ext_put_gap_in_cache(struct ext3_extents_tree *tree,
1340 +                         struct ext3_ext_path *path,
1341 +                         unsigned long block)
1342 +{
1343 +       int depth = EXT_DEPTH(tree);
1344 +       unsigned long lblock, len;
1345 +       struct ext3_extent *ex;
1346 +
1347 +       if (!tree->cex)
1348 +               return;
1349 +
1350 +       ex = path[depth].p_ext;
1351 +       if (ex == NULL) {
1352 +               /* there is no extent yet, so gap is [0;-] */
1353 +               lblock = 0;
1354 +               len = EXT_MAX_BLOCK;
1355 +               ext_debug(tree, "cache gap(whole file):");
1356 +       } else if (block < ex->ee_block) {
1357 +               lblock = block;
1358 +               len = ex->ee_block - block;
1359 +               ext_debug(tree, "cache gap(before): %lu [%lu:%lu]",
1360 +                         (unsigned long) block,
1361 +                         (unsigned long) ex->ee_block,
1362 +                         (unsigned long) ex->ee_len);
1363 +       } else if (block >= ex->ee_block + ex->ee_len) {
1364 +               lblock = ex->ee_block + ex->ee_len;
1365 +               len = ext3_ext_next_allocated_block(path);
1366 +               ext_debug(tree, "cache gap(after): [%lu:%lu] %lu",
1367 +                         (unsigned long) ex->ee_block,
1368 +                         (unsigned long) ex->ee_len,
1369 +                         (unsigned long) block);
1370 +               EXT_ASSERT(len > lblock);
1371 +               len = len - lblock;
1372 +       } else {
1373 +               lblock = len = 0;
1374 +               BUG();
1375 +       }
1376 +
1377 +       ext_debug(tree, " -> %lu:%lu\n", (unsigned long) lblock, len);
1378 +       ext3_ext_put_in_cache(tree, lblock, len, 0, EXT3_EXT_CACHE_GAP);
1379 +}
1380 +
1381 +static inline int
1382 +ext3_ext_in_cache(struct ext3_extents_tree *tree, unsigned long block,
1383 +                 struct ext3_extent *ex)
1384 +{
1385 +       struct ext3_ext_cache *cex = tree->cex;
1386 +
1387 +       /* is there cache storage at all? */
1388 +       if (!cex)
1389 +               return EXT3_EXT_CACHE_NO;
1390 +
1391 +       /* has cache valid data? */
1392 +       if (cex->ec_type == EXT3_EXT_CACHE_NO)
1393 +               return EXT3_EXT_CACHE_NO;
1394 +
1395 +       EXT_ASSERT(cex->ec_type == EXT3_EXT_CACHE_GAP ||
1396 +                  cex->ec_type == EXT3_EXT_CACHE_EXTENT);
1397 +       if (block >= cex->ec_block && block < cex->ec_block + cex->ec_len) {
1398 +               ex->ee_block = cex->ec_block;
1399 +               ex->ee_start = cex->ec_start;
1400 +               ex->ee_len = cex->ec_len;
1401 +               ext_debug(tree, "%lu cached by %lu:%lu:%lu\n",
1402 +                         (unsigned long) block,
1403 +                         (unsigned long) ex->ee_block,
1404 +                         (unsigned long) ex->ee_len,
1405 +                         (unsigned long) ex->ee_start);
1406 +               return cex->ec_type;
1407 +       }
1408 +
1409 +       /* not in cache */
1410 +       return EXT3_EXT_CACHE_NO;
1411 +}
1412 +
1413 +/*
1414 + * routine removes index from the index block
1415 + * it's used in truncate case only. thus all requests are for
1416 + * last index in the block only
1417 + */
1418 +int ext3_ext_rm_idx(handle_t *handle, struct ext3_extents_tree *tree,
1419 +                   struct ext3_ext_path *path)
1420 +{
1421 +       struct buffer_head *bh;
1422 +       int err;
1423 +
1424 +       /* free index block */
1425 +       path--;
1426 +       EXT_ASSERT(path->p_hdr->eh_entries);
1427 +       if ((err = ext3_ext_get_access(handle, tree, path)))
1428 +               return err;
1429 +       path->p_hdr->eh_entries--;
1430 +       if ((err = ext3_ext_dirty(handle, tree, path)))
1431 +               return err;
1432 +       ext_debug(tree, "index is empty, remove it, free block %d\n",
1433 +                 path->p_idx->ei_leaf);
1434 +       bh = sb_get_hash_table(tree->inode->i_sb, path->p_idx->ei_leaf);
1435 +       ext3_forget(handle, 1, tree->inode, bh, path->p_idx->ei_leaf);
1436 +       ext3_free_blocks(handle, tree->inode, path->p_idx->ei_leaf, 1);
1437 +       return err;
1438 +}
1439 +
1440 +int ext3_ext_calc_credits_for_insert(struct ext3_extents_tree *tree,
1441 +                                    struct ext3_ext_path *path)
1442 +{
1443 +       int depth = EXT_DEPTH(tree);
1444 +       int needed;
1445 +
1446 +       if (path) {
1447 +               /* probably there is space in leaf? */
1448 +               if (path[depth].p_hdr->eh_entries < path[depth].p_hdr->eh_max)
1449 +                       return 1;
1450 +       }
1451 +
1452 +       /*
1453 +        * the worste case we're expecting is creation of the
1454 +        * new root (growing in depth) with index splitting
1455 +        * for splitting we have to consider depth + 1 because
1456 +        * previous growing could increase it
1457 +        */
1458 +       depth = depth + 1;
1459 +
1460 +       /*
1461 +        * growing in depth:
1462 +        * block allocation + new root + old root
1463 +        */
1464 +       needed = EXT3_ALLOC_NEEDED + 2;
1465 +
1466 +       /* index split. we may need:
1467 +        *   allocate intermediate indexes and new leaf
1468 +        *   change two blocks at each level, but root
1469 +        *   modify root block (inode)
1470 +        */
1471 +       needed += (depth * EXT3_ALLOC_NEEDED) + (2 * depth) + 1;
1472 +
1473 +       return needed;
1474 +}
1475 +
1476 +static int
1477 +ext3_ext_split_for_rm(handle_t *handle, struct ext3_extents_tree *tree,
1478 +                     struct ext3_ext_path *path, unsigned long start,
1479 +                     unsigned long end)
1480 +{
1481 +       struct ext3_extent *ex, tex;
1482 +       struct ext3_ext_path *npath;
1483 +       int depth, creds, err;
1484 +
1485 +       depth = EXT_DEPTH(tree);
1486 +       ex = path[depth].p_ext;
1487 +       EXT_ASSERT(ex);
1488 +       EXT_ASSERT(end < ex->ee_block + ex->ee_len - 1);
1489 +       EXT_ASSERT(ex->ee_block < start);
1490 +
1491 +       /* calculate tail extent */
1492 +       tex.ee_block = end + 1;
1493 +       EXT_ASSERT(tex.ee_block < ex->ee_block + ex->ee_len);
1494 +       tex.ee_len = ex->ee_block + ex->ee_len - tex.ee_block;
1495 +
1496 +       creds = ext3_ext_calc_credits_for_insert(tree, path);
1497 +       handle = ext3_ext_journal_restart(handle, creds);
1498 +       if (IS_ERR(handle))
1499 +               return PTR_ERR(handle);
1500 +
1501 +       /* calculate head extent. use primary extent */
1502 +       err = ext3_ext_get_access(handle, tree, path + depth);
1503 +       if (err)
1504 +               return err;
1505 +       ex->ee_len = start - ex->ee_block;
1506 +       err = ext3_ext_dirty(handle, tree, path + depth);
1507 +       if (err)
1508 +               return err;
1509 +
1510 +       /* FIXME: some callback to free underlying resource
1511 +        * and correct ee_start? */
1512 +       ext_debug(tree, "split extent: head %u:%u, tail %u:%u\n",
1513 +                 ex->ee_block, ex->ee_len, tex.ee_block, tex.ee_len);
1514 +
1515 +       npath = ext3_ext_find_extent(tree, ex->ee_block, NULL);
1516 +       if (IS_ERR(npath))
1517 +               return PTR_ERR(npath);
1518 +       depth = EXT_DEPTH(tree);
1519 +       EXT_ASSERT(npath[depth].p_ext->ee_block == ex->ee_block);
1520 +       EXT_ASSERT(npath[depth].p_ext->ee_len == ex->ee_len);
1521 +
1522 +       err = ext3_ext_insert_extent(handle, tree, npath, &tex);
1523 +       ext3_ext_drop_refs(npath);
1524 +       kfree(npath);
1525 +
1526 +       return err;
1527 +}
1528 +
1529 +static int
1530 +ext3_ext_rm_leaf(handle_t *handle, struct ext3_extents_tree *tree,
1531 +                struct ext3_ext_path *path, unsigned long start,
1532 +                unsigned long end)
1533 +{
1534 +       struct ext3_extent *ex, *fu = NULL, *lu, *le;
1535 +       int err = 0, correct_index = 0;
1536 +       int depth = EXT_DEPTH(tree), credits;
1537 +       struct ext3_extent_header *eh;
1538 +       unsigned a, b, block, num;
1539 +
1540 +       ext_debug(tree, "remove [%lu:%lu] in leaf\n", start, end);
1541 +       if (!path[depth].p_hdr)
1542 +               path[depth].p_hdr = EXT_BLOCK_HDR(path[depth].p_bh);
1543 +       eh = path[depth].p_hdr;
1544 +       EXT_ASSERT(eh);
1545 +       EXT_ASSERT(eh->eh_entries <= eh->eh_max);
1546 +       EXT_ASSERT(eh->eh_magic == EXT3_EXT_MAGIC);
1547 +
1548 +       /* find where to start removing */
1549 +       le = ex = EXT_LAST_EXTENT(eh);
1550 +       while (ex != EXT_FIRST_EXTENT(eh)) {
1551 +               if (ex->ee_block <= end)
1552 +                       break;
1553 +               ex--;
1554 +       }
1555 +
1556 +       if (start > ex->ee_block && end < ex->ee_block + ex->ee_len - 1) {
1557 +               /* removal of internal part of the extent requested
1558 +                * tail and head must be placed in different extent
1559 +                * so, we have to insert one more extent */
1560 +               path[depth].p_ext = ex;
1561 +               return ext3_ext_split_for_rm(handle, tree, path, start, end);
1562 +       }
1563 +
1564 +       lu = ex;
1565 +       while (ex >= EXT_FIRST_EXTENT(eh) && ex->ee_block + ex->ee_len > start) {
1566 +               ext_debug(tree, "remove ext %u:%u\n", ex->ee_block, ex->ee_len);
1567 +               path[depth].p_ext = ex;
1568 +
1569 +               a = ex->ee_block > start ? ex->ee_block : start;
1570 +               b = ex->ee_block + ex->ee_len - 1 < end ?
1571 +                       ex->ee_block + ex->ee_len - 1 : end;
1572 +
1573 +               ext_debug(tree, "  border %u:%u\n", a, b);
1574 +
1575 +               if (a != ex->ee_block && b != ex->ee_block + ex->ee_len - 1) {
1576 +                       block = 0;
1577 +                       num = 0;
1578 +                       BUG();
1579 +               } else if (a != ex->ee_block) {
1580 +                       /* remove tail of the extent */
1581 +                       block = ex->ee_block;
1582 +                       num = a - block;
1583 +               } else if (b != ex->ee_block + ex->ee_len - 1) {
1584 +                       /* remove head of the extent */
1585 +                       block = a;
1586 +                       num = b - a;
1587 +               } else {
1588 +                       /* remove whole extent: excelent! */
1589 +                       block = ex->ee_block;
1590 +                       num = 0;
1591 +                       EXT_ASSERT(a == ex->ee_block &&
1592 +                                  b == ex->ee_block + ex->ee_len - 1);
1593 +               }
1594 +
1595 +               if (ex == EXT_FIRST_EXTENT(eh))
1596 +                       correct_index = 1;
1597 +
1598 +               credits = 1;
1599 +               if (correct_index)
1600 +                       credits += (EXT_DEPTH(tree) * EXT3_ALLOC_NEEDED) + 1;
1601 +               if (tree->ops->remove_extent_credits)
1602 +                       credits+=tree->ops->remove_extent_credits(tree,ex,a,b);
1603 +
1604 +               handle = ext3_ext_journal_restart(handle, credits);
1605 +               if (IS_ERR(handle)) {
1606 +                       err = PTR_ERR(handle);
1607 +                       goto out;
1608 +               }
1609 +
1610 +               err = ext3_ext_get_access(handle, tree, path + depth);
1611 +               if (err)
1612 +                       goto out;
1613 +
1614 +               if (tree->ops->remove_extent)
1615 +                       err = tree->ops->remove_extent(tree, ex, a, b);
1616 +               if (err)
1617 +                       goto out;
1618 +
1619 +               if (num == 0) {
1620 +                       /* this extent is removed entirely mark slot unused */
1621 +                       ex->ee_start = 0;
1622 +                       eh->eh_entries--;
1623 +                       fu = ex;
1624 +               }
1625 +
1626 +               ex->ee_block = block;
1627 +               ex->ee_len = num;
1628 +
1629 +               err = ext3_ext_dirty(handle, tree, path + depth);
1630 +               if (err)
1631 +                       goto out;
1632 +
1633 +               ext_debug(tree, "new extent: %u:%u:%u\n",
1634 +                         ex->ee_block, ex->ee_len, ex->ee_start);
1635 +               ex--;
1636 +       }
1637 +
1638 +       if (fu) {
1639 +               /* reuse unused slots */
1640 +               while (lu < le) {
1641 +                       if (lu->ee_start) {
1642 +                               *fu = *lu;
1643 +                               lu->ee_start = 0;
1644 +                               fu++;
1645 +                       }
1646 +                       lu++;
1647 +               }
1648 +       }
1649 +
1650 +       if (correct_index && eh->eh_entries)
1651 +               err = ext3_ext_correct_indexes(handle, tree, path);
1652 +
1653 +       /* if this leaf is free, then we should
1654 +        * remove it from index block above */
1655 +       if (err == 0 && eh->eh_entries == 0 && path[depth].p_bh != NULL)
1656 +               err = ext3_ext_rm_idx(handle, tree, path + depth);
1657 +
1658 +out:
1659 +       return err;
1660 +}
1661 +
1662 +
1663 +static struct ext3_extent_idx *
1664 +ext3_ext_last_covered(struct ext3_extent_header *hdr, unsigned long block)
1665 +{
1666 +       struct ext3_extent_idx *ix;
1667 +
1668 +       ix = EXT_LAST_INDEX(hdr);
1669 +       while (ix != EXT_FIRST_INDEX(hdr)) {
1670 +               if (ix->ei_block <= block)
1671 +                       break;
1672 +               ix--;
1673 +       }
1674 +       return ix;
1675 +}
1676 +
1677 +/*
1678 + * returns 1 if current index have to be freed (even partial)
1679 + */
1680 +static int inline
1681 +ext3_ext_more_to_rm(struct ext3_ext_path *path)
1682 +{
1683 +       EXT_ASSERT(path->p_idx);
1684 +
1685 +       if (path->p_idx < EXT_FIRST_INDEX(path->p_hdr))
1686 +               return 0;
1687 +
1688 +       /*
1689 +        * if truncate on deeper level happened it it wasn't partial
1690 +        * so we have to consider current index for truncation
1691 +        */
1692 +       if (path->p_hdr->eh_entries == path->p_block)
1693 +               return 0;
1694 +       return 1;
1695 +}
1696 +
1697 +int ext3_ext_remove_space(struct ext3_extents_tree *tree,
1698 +                         unsigned long start, unsigned long end)
1699 +{
1700 +       struct inode *inode = tree->inode;
1701 +       struct super_block *sb = inode->i_sb;
1702 +       int depth = EXT_DEPTH(tree);
1703 +       struct ext3_ext_path *path;
1704 +       handle_t *handle;
1705 +       int i = 0, err = 0;
1706 +
1707 +       ext_debug(tree, "space to be removed: %lu:%lu\n", start, end);
1708 +
1709 +       /* probably first extent we're gonna free will be last in block */
1710 +       handle = ext3_journal_start(inode, depth + 1);
1711 +       if (IS_ERR(handle))
1712 +               return PTR_ERR(handle);
1713 +
1714 +       ext3_ext_invalidate_cache(tree);
1715 +
1716 +       /*
1717 +        * we start scanning from right side freeing all the blocks
1718 +        * after i_size and walking into the deep
1719 +        */
1720 +       path = kmalloc(sizeof(struct ext3_ext_path) * (depth + 1), GFP_KERNEL);
1721 +       if (IS_ERR(path)) {
1722 +               ext3_error(sb, __FUNCTION__, "Can't allocate path array");
1723 +               ext3_journal_stop(handle, inode);
1724 +               return -ENOMEM;
1725 +       }
1726 +       memset(path, 0, sizeof(struct ext3_ext_path) * (depth + 1));
1727 +       path[i].p_hdr = EXT_ROOT_HDR(tree);
1728 +
1729 +       while (i >= 0 && err == 0) {
1730 +               if (i == depth) {
1731 +                       /* this is leaf block */
1732 +                       err = ext3_ext_rm_leaf(handle, tree, path, start, end);
1733 +                       /* root level have p_bh == NULL, brelse() eats this */
1734 +                       brelse(path[i].p_bh);
1735 +                       i--;
1736 +                       continue;
1737 +               }
1738 +
1739 +               /* this is index block */
1740 +               if (!path[i].p_hdr) {
1741 +                       ext_debug(tree, "initialize header\n");
1742 +                       path[i].p_hdr = EXT_BLOCK_HDR(path[i].p_bh);
1743 +               }
1744 +
1745 +               EXT_ASSERT(path[i].p_hdr->eh_entries <= path[i].p_hdr->eh_max);
1746 +               EXT_ASSERT(path[i].p_hdr->eh_magic == EXT3_EXT_MAGIC);
1747 +
1748 +               if (!path[i].p_idx) {
1749 +                       /* this level hasn't touched yet */
1750 +                       path[i].p_idx =
1751 +                               ext3_ext_last_covered(path[i].p_hdr, end);
1752 +                       path[i].p_block = path[i].p_hdr->eh_entries + 1;
1753 +                       ext_debug(tree, "init index ptr: hdr 0x%p, num %d\n",
1754 +                                 path[i].p_hdr, path[i].p_hdr->eh_entries);
1755 +               } else {
1756 +                       /* we've already was here, see at next index */
1757 +                       path[i].p_idx--;
1758 +               }
1759 +
1760 +               ext_debug(tree, "level %d - index, first 0x%p, cur 0x%p\n",
1761 +                         i, EXT_FIRST_INDEX(path[i].p_hdr),
1762 +                         path[i].p_idx);
1763 +               if (ext3_ext_more_to_rm(path + i)) {
1764 +                       /* go to the next level */
1765 +                       ext_debug(tree, "move to level %d (block %d)\n",
1766 +                                 i + 1, path[i].p_idx->ei_leaf);
1767 +                       memset(path + i + 1, 0, sizeof(*path));
1768 +                       path[i+1].p_bh = sb_bread(sb, path[i].p_idx->ei_leaf);
1769 +                       if (!path[i+1].p_bh) {
1770 +                               /* should we reset i_size? */
1771 +                               err = -EIO;
1772 +                               break;
1773 +                       }
1774 +                       /* put actual number of indexes to know is this
1775 +                        * number got changed at the next iteration */
1776 +                       path[i].p_block = path[i].p_hdr->eh_entries;
1777 +                       i++;
1778 +               } else {
1779 +                       /* we finish processing this index, go up */
1780 +                       if (path[i].p_hdr->eh_entries == 0 && i > 0) {
1781 +                               /* index is empty, remove it
1782 +                                * handle must be already prepared by the
1783 +                                * truncatei_leaf() */
1784 +                               err = ext3_ext_rm_idx(handle, tree, path + i);
1785 +                       }
1786 +                       /* root level have p_bh == NULL, brelse() eats this */
1787 +                       brelse(path[i].p_bh);
1788 +                       i--;
1789 +                       ext_debug(tree, "return to level %d\n", i);
1790 +               }
1791 +       }
1792 +
1793 +       /* TODO: flexible tree reduction should be here */
1794 +       if (path->p_hdr->eh_entries == 0) {
1795 +               /*
1796 +                * truncate to zero freed all the tree
1797 +                * so, we need to correct eh_depth
1798 +                */
1799 +               err = ext3_ext_get_access(handle, tree, path);
1800 +               if (err == 0) {
1801 +                       EXT_ROOT_HDR(tree)->eh_depth = 0;
1802 +                       EXT_ROOT_HDR(tree)->eh_max = ext3_ext_space_root(tree);
1803 +                       err = ext3_ext_dirty(handle, tree, path);
1804 +               }
1805 +       }
1806 +       ext3_ext_tree_changed(tree);
1807 +
1808 +       kfree(path);
1809 +       ext3_journal_stop(handle, inode);
1810 +
1811 +       return err;
1812 +}
1813 +
1814 +/*
1815 + * called at mount time
1816 + */
1817 +void ext3_ext_init(struct super_block *sb)
1818 +{
1819 +       /*
1820 +        * possible initialization would be here
1821 +        */
1822 +
1823 +       if (test_opt(sb, EXTENTS)) {
1824 +               printk("EXT3-fs: file extents enabled");
1825 +#ifdef AGRESSIVE_TEST
1826 +               printk(", agressive tests");
1827 +#endif
1828 +#ifdef CHECK_BINSEARCH
1829 +               printk(", check binsearch");
1830 +#endif
1831 +               printk("\n");
1832 +       }
1833 +}
1834 +
1835 +/*
1836 + * called at umount time
1837 + */
1838 +void ext3_ext_release(struct super_block *sb)
1839 +{
1840 +}
1841 +
1842 +/************************************************************************
1843 + * VFS related routines
1844 + ************************************************************************/
1845 +
1846 +static int ext3_get_inode_write_access(handle_t *handle, void *buffer)
1847 +{
1848 +       /* we use in-core data, not bh */
1849 +       return 0;
1850 +}
1851 +
1852 +static int ext3_mark_buffer_dirty(handle_t *handle, void *buffer)
1853 +{
1854 +       struct inode *inode = buffer;
1855 +       return ext3_mark_inode_dirty(handle, inode);
1856 +}
1857 +
1858 +static int ext3_ext_mergable(struct ext3_extent *ex1,
1859 +                            struct ext3_extent *ex2)
1860 +{
1861 +       /* FIXME: support for large fs */
1862 +       if (ex1->ee_start + ex1->ee_len == ex2->ee_start)
1863 +               return 1;
1864 +       return 0;
1865 +}
1866 +
1867 +static int
1868 +ext3_remove_blocks_credits(struct ext3_extents_tree *tree,
1869 +                          struct ext3_extent *ex,
1870 +                          unsigned long from, unsigned long to)
1871 +{
1872 +       int needed;
1873 +
1874 +       /* at present, extent can't cross block group */;
1875 +       needed = 4; /* bitmap + group desc + sb + inode */
1876 +
1877 +#ifdef CONFIG_QUOTA
1878 +       needed += 2 * EXT3_SINGLEDATA_TRANS_BLOCKS;
1879 +#endif
1880 +       return needed;
1881 +}
1882 +
1883 +static int
1884 +ext3_remove_blocks(struct ext3_extents_tree *tree,
1885 +                  struct ext3_extent *ex,
1886 +                  unsigned long from, unsigned long to)
1887 +{
1888 +       int needed = ext3_remove_blocks_credits(tree, ex, from, to);
1889 +       handle_t *handle = ext3_journal_start(tree->inode, needed);
1890 +       struct buffer_head *bh;
1891 +       int i;
1892 +
1893 +       if (IS_ERR(handle))
1894 +               return PTR_ERR(handle);
1895 +       if (from >= ex->ee_block && to == ex->ee_block + ex->ee_len - 1) {
1896 +               /* tail removal */
1897 +               unsigned long num, start;
1898 +               num = ex->ee_block + ex->ee_len - from;
1899 +               start = ex->ee_start + ex->ee_len - num;
1900 +               ext_debug(tree, "free last %lu blocks starting %lu\n",
1901 +                         num, start);
1902 +               for (i = 0; i < num; i++) {
1903 +                       bh = sb_get_hash_table(tree->inode->i_sb, start + i);
1904 +                       ext3_forget(handle, 0, tree->inode, bh, start + i);
1905 +               }
1906 +               ext3_free_blocks(handle, tree->inode, start, num);
1907 +       } else if (from == ex->ee_block && to <= ex->ee_block + ex->ee_len - 1) {
1908 +               printk("strange request: removal %lu-%lu from %u:%u\n",
1909 +                      from, to, ex->ee_block, ex->ee_len);
1910 +       } else {
1911 +               printk("strange request: removal(2) %lu-%lu from %u:%u\n",
1912 +                      from, to, ex->ee_block, ex->ee_len);
1913 +       }
1914 +       ext3_journal_stop(handle, tree->inode);
1915 +       return 0;
1916 +}
1917 +
1918 +int ext3_ext_find_goal(struct inode *inode, struct ext3_ext_path *path,
1919 +                      unsigned long block)
1920 +{
1921 +       struct ext3_inode_info *ei = EXT3_I(inode);
1922 +       unsigned long bg_start;
1923 +       unsigned long colour;
1924 +       int depth;
1925 +
1926 +       if (path) {
1927 +               struct ext3_extent *ex;
1928 +               depth = path->p_depth;
1929 +
1930 +               /* try to predict block placement */
1931 +               if ((ex = path[depth].p_ext))
1932 +                       return ex->ee_start + (block - ex->ee_block);
1933 +
1934 +               /* it looks index is empty
1935 +                * try to find starting from index itself */
1936 +               if (path[depth].p_bh)
1937 +                       return path[depth].p_bh->b_blocknr;
1938 +       }
1939 +
1940 +       /* OK. use inode's group */
1941 +       bg_start = (ei->i_block_group * EXT3_BLOCKS_PER_GROUP(inode->i_sb)) +
1942 +               le32_to_cpu(EXT3_SB(inode->i_sb)->s_es->s_first_data_block);
1943 +       colour = (current->pid % 16) *
1944 +                       (EXT3_BLOCKS_PER_GROUP(inode->i_sb) / 16);
1945 +       return bg_start + colour + block;
1946 +}
1947 +
1948 +static int ext3_new_block_cb(handle_t *handle, struct ext3_extents_tree *tree,
1949 +                            struct ext3_ext_path *path,
1950 +                            struct ext3_extent *ex, int *err)
1951 +{
1952 +       struct inode *inode = tree->inode;
1953 +       int newblock, goal;
1954 +
1955 +       EXT_ASSERT(path);
1956 +       EXT_ASSERT(ex);
1957 +       EXT_ASSERT(ex->ee_start);
1958 +       EXT_ASSERT(ex->ee_len);
1959 +
1960 +       /* reuse block from the extent to order data/metadata */
1961 +       newblock = ex->ee_start++;
1962 +       ex->ee_len--;
1963 +       if (ex->ee_len == 0) {
1964 +               ex->ee_len = 1;
1965 +               /* allocate new block for the extent */
1966 +               goal = ext3_ext_find_goal(inode, path, ex->ee_block);
1967 +               ex->ee_start = ext3_new_block(handle, inode, goal, 0, 0, err);
1968 +               if (ex->ee_start == 0) {
1969 +                       /* error occured: restore old extent */
1970 +                       ex->ee_start = newblock;
1971 +                       return 0;
1972 +               }
1973 +       }
1974 +       return newblock;
1975 +}
1976 +
1977 +static struct ext3_extents_helpers ext3_blockmap_helpers = {
1978 +       .get_write_access       = ext3_get_inode_write_access,
1979 +       .mark_buffer_dirty      = ext3_mark_buffer_dirty,
1980 +       .mergable               = ext3_ext_mergable,
1981 +       .new_block              = ext3_new_block_cb,
1982 +       .remove_extent          = ext3_remove_blocks,
1983 +       .remove_extent_credits  = ext3_remove_blocks_credits,
1984 +};
1985 +
1986 +void ext3_init_tree_desc(struct ext3_extents_tree *tree,
1987 +                        struct inode *inode)
1988 +{
1989 +       tree->inode = inode;
1990 +       tree->root = (void *) EXT3_I(inode)->i_data;
1991 +       tree->buffer = (void *) inode;
1992 +       tree->buffer_len = sizeof(EXT3_I(inode)->i_data);
1993 +       tree->cex = (struct ext3_ext_cache *) &EXT3_I(inode)->i_cached_extent;
1994 +       tree->ops = &ext3_blockmap_helpers;
1995 +}
1996 +
1997 +int ext3_ext_get_block(handle_t *handle, struct inode *inode,
1998 +                      long iblock, struct buffer_head *bh_result, int create)
1999 +{
2000 +       struct ext3_ext_path *path = NULL;
2001 +       struct ext3_extent newex;
2002 +       struct ext3_extent *ex;
2003 +       int goal, newblock, err = 0, depth;
2004 +       struct ext3_extents_tree tree;
2005 +
2006 +       clear_bit(BH_New, &bh_result->b_state);
2007 +       ext3_init_tree_desc(&tree, inode);
2008 +       ext_debug(&tree, "block %d requested for inode %u\n",
2009 +                 (int) iblock, (unsigned) inode->i_ino);
2010 +       down_write(&EXT3_I(inode)->truncate_sem);
2011 +
2012 +       /* check in cache */
2013 +       if ((goal = ext3_ext_in_cache(&tree, iblock, &newex))) {
2014 +               if (goal == EXT3_EXT_CACHE_GAP) {
2015 +                       if (!create) {
2016 +                               /* block isn't allocated yet and
2017 +                                * user don't want to allocate it */
2018 +                               goto out2;
2019 +                       }
2020 +                       /* we should allocate requested block */
2021 +               } else if (goal == EXT3_EXT_CACHE_EXTENT) {
2022 +                       /* block is already allocated */
2023 +                       newblock = iblock - newex.ee_block + newex.ee_start;
2024 +                       goto out;
2025 +               } else {
2026 +                       EXT_ASSERT(0);
2027 +               }
2028 +       }
2029 +
2030 +       /* find extent for this block */
2031 +       path = ext3_ext_find_extent(&tree, iblock, NULL);
2032 +       if (IS_ERR(path)) {
2033 +               err = PTR_ERR(path);
2034 +               path = NULL;
2035 +               goto out2;
2036 +       }
2037 +
2038 +       depth = EXT_DEPTH(&tree);
2039 +
2040 +       /*
2041 +        * consistent leaf must not be empty
2042 +        * this situations is possible, though, _during_ tree modification
2043 +        * this is why assert can't be put in ext3_ext_find_extent()
2044 +        */
2045 +       EXT_ASSERT(path[depth].p_ext != NULL || depth == 0);
2046 +
2047 +       if ((ex = path[depth].p_ext)) {
2048 +               /* if found exent covers block, simple return it */
2049 +               if (iblock >= ex->ee_block && iblock < ex->ee_block + ex->ee_len) {
2050 +                       newblock = iblock - ex->ee_block + ex->ee_start;
2051 +                       ext_debug(&tree, "%d fit into %d:%d -> %d\n",
2052 +                                 (int) iblock, ex->ee_block, ex->ee_len,
2053 +                                 newblock);
2054 +                       ext3_ext_put_in_cache(&tree, ex->ee_block,
2055 +                                             ex->ee_len, ex->ee_start,
2056 +                                             EXT3_EXT_CACHE_EXTENT);
2057 +                       goto out;
2058 +               }
2059 +       }
2060 +
2061 +       /*
2062 +        * requested block isn't allocated yet
2063 +        * we couldn't try to create block if create flag is zero
2064 +        */
2065 +       if (!create) {
2066 +               /* put just found gap into cache to speedup subsequest reqs */
2067 +               ext3_ext_put_gap_in_cache(&tree, path, iblock);
2068 +               goto out2;
2069 +       }
2070 +
2071 +       /* allocate new block */
2072 +       goal = ext3_ext_find_goal(inode, path, iblock);
2073 +       newblock = ext3_new_block(handle, inode, goal, 0, 0, &err);
2074 +       if (!newblock)
2075 +               goto out2;
2076 +       ext_debug(&tree, "allocate new block: goal %d, found %d\n",
2077 +                 goal, newblock);
2078 +
2079 +       /* try to insert new extent into found leaf and return */
2080 +       newex.ee_block = iblock;
2081 +       newex.ee_start = newblock;
2082 +       newex.ee_len = 1;
2083 +       err = ext3_ext_insert_extent(handle, &tree, path, &newex);
2084 +       if (err)
2085 +               goto out2;
2086 +
2087 +       if (inode->i_size > EXT3_I(inode)->i_disksize)
2088 +               EXT3_I(inode)->i_disksize = inode->i_size;
2089 +
2090 +       /* previous routine could use block we allocated */
2091 +       newblock = newex.ee_start;
2092 +       set_bit(BH_New, &bh_result->b_state);
2093 +
2094 +       ext3_ext_put_in_cache(&tree, newex.ee_block, newex.ee_len,
2095 +                             newex.ee_start, EXT3_EXT_CACHE_EXTENT);
2096 +out:
2097 +       ext3_ext_show_leaf(&tree, path);
2098 +       set_bit(BH_Mapped, &bh_result->b_state);
2099 +       bh_result->b_dev = inode->i_sb->s_dev;
2100 +       bh_result->b_blocknr = newblock;
2101 +out2:
2102 +       if (path) {
2103 +               ext3_ext_drop_refs(path);
2104 +               kfree(path);
2105 +       }
2106 +       up_write(&EXT3_I(inode)->truncate_sem);
2107 +
2108 +       return err;
2109 +}
2110 +
2111 +void ext3_ext_truncate(struct inode * inode)
2112 +{
2113 +       struct address_space *mapping = inode->i_mapping;
2114 +       struct super_block *sb = inode->i_sb;
2115 +       struct ext3_extents_tree tree;
2116 +       unsigned long last_block;
2117 +       handle_t *handle;
2118 +       int err = 0;
2119 +
2120 +       ext3_init_tree_desc(&tree, inode);
2121 +
2122 +       /*
2123 +        * probably first extent we're gonna free will be last in block
2124 +        */
2125 +       err = ext3_writepage_trans_blocks(inode) + 3;
2126 +       handle = ext3_journal_start(inode, err);
2127 +       if (IS_ERR(handle))
2128 +               return;
2129 +
2130 +       ext3_block_truncate_page(handle, mapping, inode->i_size);
2131 +
2132 +       down_write(&EXT3_I(inode)->truncate_sem);
2133 +       ext3_ext_invalidate_cache(&tree);
2134 +
2135 +       /*
2136 +        * TODO: optimization is possible here
2137 +        * probably we need not scaning at all,
2138 +        * because page truncation is enough
2139 +        */
2140 +       if (ext3_orphan_add(handle, inode))
2141 +               goto out_stop;
2142 +
2143 +       /* we have to know where to truncate from in crash case */
2144 +       EXT3_I(inode)->i_disksize = inode->i_size;
2145 +       ext3_mark_inode_dirty(handle, inode);
2146 +
2147 +       last_block = (inode->i_size + sb->s_blocksize - 1) >>
2148 +                       EXT3_BLOCK_SIZE_BITS(sb);
2149 +       err = ext3_ext_remove_space(&tree, last_block, EXT_MAX_BLOCK);
2150 +
2151 +       /* In a multi-transaction truncate, we only make the final
2152 +        * transaction synchronous */
2153 +       if (IS_SYNC(inode))
2154 +               handle->h_sync = 1;
2155 +
2156 +out_stop:
2157 +       /*
2158 +        * If this was a simple ftruncate(), and the file will remain alive
2159 +        * then we need to clear up the orphan record which we created above.
2160 +        * However, if this was a real unlink then we were called by
2161 +        * ext3_delete_inode(), and we allow that function to clean up the
2162 +        * orphan info for us.
2163 +        */
2164 +       if (inode->i_nlink)
2165 +               ext3_orphan_del(handle, inode);
2166 +
2167 +       up_write(&EXT3_I(inode)->truncate_sem);
2168 +       ext3_journal_stop(handle, inode);
2169 +}
2170 +
2171 +/*
2172 + * this routine calculate max number of blocks we could modify
2173 + * in order to allocate new block for an inode
2174 + */
2175 +int ext3_ext_writepage_trans_blocks(struct inode *inode, int num)
2176 +{
2177 +       struct ext3_extents_tree tree;
2178 +       int needed;
2179 +
2180 +       ext3_init_tree_desc(&tree, inode);
2181 +
2182 +       needed = ext3_ext_calc_credits_for_insert(&tree, NULL);
2183 +
2184 +       /* caller want to allocate num blocks */
2185 +       needed *= num;
2186 +
2187 +#ifdef CONFIG_QUOTA
2188 +       /*
2189 +        * FIXME: real calculation should be here
2190 +        * it depends on blockmap format of qouta file
2191 +        */
2192 +       needed += 2 * EXT3_SINGLEDATA_TRANS_BLOCKS;
2193 +#endif
2194 +
2195 +       return needed;
2196 +}
2197 +
2198 +void ext3_extents_initialize_blockmap(handle_t *handle, struct inode *inode)
2199 +{
2200 +       struct ext3_extents_tree tree;
2201 +
2202 +       ext3_init_tree_desc(&tree, inode);
2203 +       ext3_extent_tree_init(handle, &tree);
2204 +}
2205 +
2206 +static int
2207 +ext3_ext_store_extent_cb(struct ext3_extents_tree *tree,
2208 +                        struct ext3_ext_path *path,
2209 +                        struct ext3_ext_cache *newex)
2210 +{
2211 +       struct ext3_extent_buf *buf = (struct ext3_extent_buf *) tree->private;
2212 +
2213 +       if (newex->ec_type != EXT3_EXT_CACHE_EXTENT)
2214 +               return EXT_CONTINUE;
2215 +
2216 +       if (buf->err < 0)
2217 +               return EXT_BREAK;
2218 +       if (buf->cur - buf->buffer + sizeof(*newex) > buf->buflen)
2219 +               return EXT_BREAK;
2220 +
2221 +       if (!copy_to_user(buf->cur, newex, sizeof(*newex))) {
2222 +               buf->err++;
2223 +               buf->cur += sizeof(*newex);
2224 +       } else {
2225 +               buf->err = -EFAULT;
2226 +               return EXT_BREAK;
2227 +       }
2228 +       return EXT_CONTINUE;
2229 +}
2230 +
2231 +static int
2232 +ext3_ext_collect_stats_cb(struct ext3_extents_tree *tree,
2233 +                         struct ext3_ext_path *path,
2234 +                         struct ext3_ext_cache *ex)
2235 +{
2236 +       struct ext3_extent_tree_stats *buf =
2237 +               (struct ext3_extent_tree_stats *) tree->private;
2238 +       int depth;
2239 +
2240 +       if (ex->ec_type != EXT3_EXT_CACHE_EXTENT)
2241 +               return EXT_CONTINUE;
2242 +
2243 +       depth = EXT_DEPTH(tree);
2244 +       buf->extents_num++;
2245 +       if (path[depth].p_ext == EXT_FIRST_EXTENT(path[depth].p_hdr))
2246 +               buf->leaf_num++;
2247 +       return EXT_CONTINUE;
2248 +}
2249 +
2250 +int ext3_ext_ioctl(struct inode *inode, struct file *filp, unsigned int cmd,
2251 +                  unsigned long arg)
2252 +{
2253 +       int err = 0;
2254 +
2255 +       if (!(EXT3_I(inode)->i_flags & EXT3_EXTENTS_FL))
2256 +               return -EINVAL;
2257 +
2258 +       if (cmd == EXT3_IOC_GET_EXTENTS) {
2259 +               struct ext3_extent_buf buf;
2260 +               struct ext3_extents_tree tree;
2261 +
2262 +               if (copy_from_user(&buf, (void *) arg, sizeof(buf)))
2263 +                       return -EFAULT;
2264 +
2265 +               ext3_init_tree_desc(&tree, inode);
2266 +               buf.cur = buf.buffer;
2267 +               buf.err = 0;
2268 +               tree.private = &buf;
2269 +               down_write(&EXT3_I(inode)->truncate_sem);
2270 +               err = ext3_ext_walk_space(&tree, buf.start, EXT_MAX_BLOCK,
2271 +                                         ext3_ext_store_extent_cb);
2272 +               up_write(&EXT3_I(inode)->truncate_sem);
2273 +               if (err == 0)
2274 +                       err = buf.err;
2275 +       } else if (cmd == EXT3_IOC_GET_TREE_STATS) {
2276 +               struct ext3_extent_tree_stats buf;
2277 +               struct ext3_extents_tree tree;
2278 +
2279 +               ext3_init_tree_desc(&tree, inode);
2280 +               down_write(&EXT3_I(inode)->truncate_sem);
2281 +               buf.depth = EXT_DEPTH(&tree);
2282 +               buf.extents_num = 0;
2283 +               buf.leaf_num = 0;
2284 +               tree.private = &buf;
2285 +               err = ext3_ext_walk_space(&tree, 0, EXT_MAX_BLOCK,
2286 +                                         ext3_ext_collect_stats_cb);
2287 +               up_write(&EXT3_I(inode)->truncate_sem);
2288 +               if (!err)
2289 +                       err = copy_to_user((void *) arg, &buf, sizeof(buf));
2290 +       } else if (cmd == EXT3_IOC_GET_TREE_DEPTH) {
2291 +               struct ext3_extents_tree tree;
2292 +               ext3_init_tree_desc(&tree, inode);
2293 +               down_write(&EXT3_I(inode)->truncate_sem);
2294 +               err = EXT_DEPTH(&tree);
2295 +               up_write(&EXT3_I(inode)->truncate_sem);
2296 +       }
2297 +
2298 +       return err;
2299 +}
2300 +
2301 +EXPORT_SYMBOL(ext3_init_tree_desc);
2302 +EXPORT_SYMBOL(ext3_mark_inode_dirty);
2303 +EXPORT_SYMBOL(ext3_ext_invalidate_cache);
2304 +EXPORT_SYMBOL(ext3_ext_insert_extent);
2305 +EXPORT_SYMBOL(ext3_ext_walk_space);
2306 +EXPORT_SYMBOL(ext3_ext_find_goal);
2307 +EXPORT_SYMBOL(ext3_ext_calc_credits_for_insert);
2308 Index: linux-2.4.24/fs/ext3/ialloc.c
2309 ===================================================================
2310 --- linux-2.4.24.orig/fs/ext3/ialloc.c  2004-11-02 20:28:32.000000000 +0300
2311 +++ linux-2.4.24/fs/ext3/ialloc.c       2004-11-02 20:32:17.000000000 +0300
2312 @@ -592,6 +592,19 @@
2313                 iloc.bh = NULL;
2314                 goto fail;
2315         }
2316 +       if (test_opt(sb, EXTENTS) && S_ISREG(inode->i_mode)) {
2317 +               EXT3_I(inode)->i_flags |= EXT3_EXTENTS_FL;
2318 +               memset(&EXT3_I(inode)->i_cached_extent, 0, sizeof(__u32) * 4);
2319 +               ext3_extents_initialize_blockmap(handle, inode);
2320 +               if (!EXT3_HAS_INCOMPAT_FEATURE(sb, EXT3_FEATURE_INCOMPAT_EXTENTS)) {
2321 +                       err = ext3_journal_get_write_access(handle, EXT3_SB(sb)->s_sbh);
2322 +                       if (err) goto fail;
2323 +                       EXT3_SET_INCOMPAT_FEATURE(sb, EXT3_FEATURE_INCOMPAT_EXTENTS);
2324 +                       BUFFER_TRACE(EXT3_SB(sb)->s_sbh, "call ext3_journal_dirty_metadata");
2325 +                       err = ext3_journal_dirty_metadata(handle, EXT3_SB(sb)->s_sbh);
2326 +               }
2327 +       }
2328 +
2329         err = ext3_mark_iloc_dirty(handle, inode, &iloc);
2330         if (err) goto fail;
2331
2332 Index: linux-2.4.24/fs/ext3/inode.c
2333 ===================================================================
2334 --- linux-2.4.24.orig/fs/ext3/inode.c   2004-11-02 20:28:33.000000000 +0300
2335 +++ linux-2.4.24/fs/ext3/inode.c        2004-11-02 20:32:17.000000000 +0300
2336 @@ -848,6 +848,15 @@
2337         goto reread;
2338  }
2339
2340 +static inline int
2341 +ext3_get_block_wrap(handle_t *handle, struct inode *inode, long block,
2342 +                   struct buffer_head *bh, int create)
2343 +{
2344 +       if (EXT3_I(inode)->i_flags & EXT3_EXTENTS_FL)
2345 +               return ext3_ext_get_block(handle, inode, block, bh, create);
2346 +       return ext3_get_block_handle(handle, inode, block, bh, create);
2347 +}
2348 +
2349  /*
2350   * The BKL is not held on entry here.
2351   */
2352 @@ -861,7 +870,7 @@
2353                 handle = ext3_journal_current_handle();
2354                 J_ASSERT(handle != 0);
2355         }
2356 -       ret = ext3_get_block_handle(handle, inode, iblock, bh_result, create);
2357 +       ret = ext3_get_block_wrap(handle, inode, iblock, bh_result, create);
2358         return ret;
2359  }
2360
2361 @@ -879,7 +888,7 @@
2362         dummy.b_state = 0;
2363         dummy.b_blocknr = -1000;
2364         buffer_trace_init(&dummy.b_history);
2365 -       *errp = ext3_get_block_handle(handle, inode, block, &dummy, create);
2366 +       *errp = ext3_get_block_wrap(handle, inode, block, &dummy, create);
2367         if (!*errp && buffer_mapped(&dummy)) {
2368                 struct buffer_head *bh;
2369                 bh = sb_getblk(inode->i_sb, dummy.b_blocknr);
2370 @@ -1403,7 +1412,7 @@
2371   * This required during truncate. We need to physically zero the tail end
2372   * of that block so it doesn't yield old data if the file is later grown.
2373   */
2374 -static int ext3_block_truncate_page(handle_t *handle,
2375 +int ext3_block_truncate_page(handle_t *handle,
2376                 struct address_space *mapping, loff_t from)
2377  {
2378         unsigned long index = from >> PAGE_CACHE_SHIFT;
2379 @@ -1889,6 +1898,9 @@
2380
2381         ext3_discard_prealloc(inode);
2382
2383 +       if (EXT3_I(inode)->i_flags & EXT3_EXTENTS_FL)
2384 +               return ext3_ext_truncate(inode);
2385 +
2386         handle = start_transaction(inode);
2387         if (IS_ERR(handle))
2388                 return;         /* AKPM: return what? */
2389 @@ -2225,6 +2237,7 @@
2390         for (block = 0; block < EXT3_N_BLOCKS; block++)
2391                 inode->u.ext3_i.i_data[block] = iloc.raw_inode->i_block[block];
2392         INIT_LIST_HEAD(&inode->u.ext3_i.i_orphan);
2393 +       memset(&EXT3_I(inode)->i_cached_extent, 0, sizeof(__u32) * 4);
2394
2395         if (EXT3_INODE_SIZE(inode->i_sb) > EXT3_GOOD_OLD_INODE_SIZE)
2396                 inode->u.ext3_i.i_extra_isize =
2397 @@ -2537,6 +2550,9 @@
2398         int indirects = (EXT3_NDIR_BLOCKS % bpp) ? 5 : 3;
2399         int ret;
2400
2401 +       if (EXT3_I(inode)->i_flags & EXT3_EXTENTS_FL)
2402 +               return ext3_ext_writepage_trans_blocks(inode, bpp);
2403 +
2404         if (ext3_should_journal_data(inode))
2405                 ret = 3 * (bpp + indirects) + 2;
2406         else
2407 @@ -2973,7 +2989,7 @@
2408
2409         /* alloc blocks one by one */
2410         for (i = 0; i < nblocks; i++) {
2411 -               ret = ext3_get_block_handle(handle, inode, blocks[i],
2412 +               ret = ext3_get_block_wrap(handle, inode, blocks[i],
2413                                                 &bh_tmp, 1);
2414                 if (ret)
2415                         break;
2416 @@ -3049,7 +3065,7 @@
2417                  if (blocks[i] != 0)
2418                          continue;
2419
2420 -                rc = ext3_get_block_handle(handle, inode, iblock, &bh, 1);
2421 +                rc = ext3_get_block_wrap(handle, inode, iblock, &bh, 1);
2422                  if (rc) {
2423                          printk(KERN_INFO "ext3_map_inode_page: error %d "
2424                                 "allocating block %ld\n", rc, iblock);
2425 Index: linux-2.4.24/fs/ext3/Makefile
2426 ===================================================================
2427 --- linux-2.4.24.orig/fs/ext3/Makefile  2004-11-02 20:28:32.000000000 +0300
2428 +++ linux-2.4.24/fs/ext3/Makefile       2004-11-02 20:32:17.000000000 +0300
2429 @@ -13,7 +13,9 @@
2430
2431  obj-y    := balloc.o bitmap.o dir.o file.o fsync.o ialloc.o inode.o iopen.o \
2432                 ioctl.o namei.o super.o symlink.o hash.o ext3-exports.o \
2433 -               xattr_trusted.o
2434 +               xattr_trusted.o extents.o
2435 +export-objs += extents.o
2436 +
2437  obj-m    := $(O_TARGET)
2438
2439  export-objs += xattr.o
2440 Index: linux-2.4.24/fs/ext3/super.c
2441 ===================================================================
2442 --- linux-2.4.24.orig/fs/ext3/super.c   2004-11-02 20:28:32.000000000 +0300
2443 +++ linux-2.4.24/fs/ext3/super.c        2004-11-02 20:32:17.000000000 +0300
2444 @@ -532,6 +532,7 @@
2445  #ifdef EXT3_DELETE_THREAD
2446         J_ASSERT(sbi->s_delete_inodes == 0);
2447  #endif
2448 +       ext3_ext_release(sb);
2449         ext3_xattr_put_super(sb);
2450         journal_destroy(sbi->s_journal);
2451         if (!(sb->s_flags & MS_RDONLY)) {
2452 @@ -704,6 +705,10 @@
2453                                 return 0;
2454                         }
2455                 }
2456 +               else if (!strcmp (this_char, "extents"))
2457 +                       set_opt (*mount_options, EXTENTS);
2458 +               else if (!strcmp (this_char, "extdebug"))
2459 +                       set_opt (*mount_options, EXTDEBUG);
2460                 else if (!strcmp (this_char, "grpid") ||
2461                          !strcmp (this_char, "bsdgroups"))
2462                         set_opt (*mount_options, GRPID);
2463 @@ -1395,6 +1400,8 @@
2464                 test_opt(sb,DATA_FLAGS) == EXT3_MOUNT_ORDERED_DATA ? "ordered":
2465                 "writeback");
2466
2467 +       ext3_ext_init(sb);
2468 +
2469         return sb;
2470
2471  failed_mount3:
2472 Index: linux-2.4.24/fs/ext3/ioctl.c
2473 ===================================================================
2474 --- linux-2.4.24.orig/fs/ext3/ioctl.c   2004-11-02 20:28:29.000000000 +0300
2475 +++ linux-2.4.24/fs/ext3/ioctl.c        2004-11-02 20:32:17.000000000 +0300
2476 @@ -174,6 +174,10 @@
2477                         return ret;
2478                 }
2479  #endif
2480 +       case EXT3_IOC_GET_EXTENTS:
2481 +       case EXT3_IOC_GET_TREE_STATS:
2482 +       case EXT3_IOC_GET_TREE_DEPTH:
2483 +               return ext3_ext_ioctl(inode, filp, cmd, arg);
2484         default:
2485                 return -ENOTTY;
2486         }
2487 Index: linux-2.4.24/include/linux/ext3_fs.h
2488 ===================================================================
2489 --- linux-2.4.24.orig/include/linux/ext3_fs.h   2004-11-02 20:28:32.000000000 +0300
2490 +++ linux-2.4.24/include/linux/ext3_fs.h        2004-11-02 20:32:17.000000000 +0300
2491 @@ -184,8 +184,9 @@
2492  #define EXT3_IMAGIC_FL                 0x00002000 /* AFS directory */
2493  #define EXT3_JOURNAL_DATA_FL           0x00004000 /* file data should be journaled */
2494  #define EXT3_RESERVED_FL               0x80000000 /* reserved for ext3 lib */
2495 +#define EXT3_EXTENTS_FL                        0x00080000 /* Inode uses extents */
2496
2497 -#define EXT3_FL_USER_VISIBLE           0x00005FFF /* User visible flags */
2498 +#define EXT3_FL_USER_VISIBLE           0x00085FFF /* User visible flags */
2499  #define EXT3_FL_USER_MODIFIABLE                0x000000FF /* User modifiable flags */
2500
2501  /*
2502 @@ -208,6 +209,9 @@
2503  #ifdef CONFIG_JBD_DEBUG
2504  #define EXT3_IOC_WAIT_FOR_READONLY     _IOR('f', 99, long)
2505  #endif
2506 +#define EXT3_IOC_GET_EXTENTS           _IOR('f', 5, long)
2507 +#define EXT3_IOC_GET_TREE_DEPTH                _IOR('f', 6, long)
2508 +#define EXT3_IOC_GET_TREE_STATS                _IOR('f', 7, long)
2509
2510  /*
2511   * Structure of an inode on the disk
2512 @@ -327,6 +331,8 @@
2513  #define EXT3_MOUNT_ASYNCDEL            0x20000 /* Delayed deletion */
2514  #define EXT3_MOUNT_IOPEN               0x40000 /* Allow access via iopen */
2515  #define EXT3_MOUNT_IOPEN_NOPRIV                0x80000 /* Make iopen world-readable */
2516 +#define EXT3_MOUNT_EXTENTS             0x100000/* Extents support */
2517 +#define EXT3_MOUNT_EXTDEBUG            0x200000/* Extents debug */
2518
2519  /* Compatibility, for having both ext2_fs.h and ext3_fs.h included at once */
2520  #ifndef _LINUX_EXT2_FS_H
2521 @@ -503,10 +509,12 @@
2522  #define EXT3_FEATURE_INCOMPAT_FILETYPE         0x0002
2523  #define EXT3_FEATURE_INCOMPAT_RECOVER          0x0004 /* Needs recovery */
2524  #define EXT3_FEATURE_INCOMPAT_JOURNAL_DEV      0x0008 /* Journal device */
2525 +#define EXT3_FEATURE_INCOMPAT_EXTENTS          0x0040 /* extents support */
2526
2527  #define EXT3_FEATURE_COMPAT_SUPP       EXT2_FEATURE_COMPAT_EXT_ATTR
2528  #define EXT3_FEATURE_INCOMPAT_SUPP     (EXT3_FEATURE_INCOMPAT_FILETYPE| \
2529 -                                        EXT3_FEATURE_INCOMPAT_RECOVER)
2530 +                                        EXT3_FEATURE_INCOMPAT_RECOVER| \
2531 +                                        EXT3_FEATURE_INCOMPAT_EXTENTS)
2532  #define EXT3_FEATURE_RO_COMPAT_SUPP    (EXT3_FEATURE_RO_COMPAT_SPARSE_SUPER| \
2533                                          EXT3_FEATURE_RO_COMPAT_LARGE_FILE| \
2534                                          EXT3_FEATURE_RO_COMPAT_BTREE_DIR)
2535 @@ -688,6 +696,7 @@
2536  extern unsigned long ext3_count_free (struct buffer_head *, unsigned);
2537
2538  /* inode.c */
2539 +extern int ext3_block_truncate_page(handle_t *, struct address_space *, loff_t);
2540  extern int ext3_forget(handle_t *, int, struct inode *, struct buffer_head *, int);
2541  extern struct buffer_head * ext3_getblk (handle_t *, struct inode *, long, int, int *);
2542  extern struct buffer_head * ext3_bread (handle_t *, struct inode *, int, int, int *);
2543 @@ -769,6 +778,16 @@
2544  extern struct inode_operations ext3_symlink_inode_operations;
2545  extern struct inode_operations ext3_fast_symlink_inode_operations;
2546
2547 +/* extents.c */
2548 +extern int ext3_ext_writepage_trans_blocks(struct inode *, int);
2549 +extern int ext3_ext_get_block(handle_t *, struct inode *, long,
2550 +                             struct buffer_head *, int);
2551 +extern void ext3_ext_truncate(struct inode *);
2552 +extern void ext3_ext_init(struct super_block *);
2553 +extern void ext3_ext_release(struct super_block *);
2554 +extern void ext3_extents_initialize_blockmap(handle_t *, struct inode *);
2555 +extern int ext3_ext_ioctl(struct inode *inode, struct file *filp,
2556 +                         unsigned int cmd, unsigned long arg);
2557
2558  #endif /* __KERNEL__ */
2559
2560 Index: linux-2.4.24/include/linux/ext3_extents.h
2561 ===================================================================
2562 --- linux-2.4.24.orig/include/linux/ext3_extents.h      2003-01-30 13:24:37.000000000 +0300
2563 +++ linux-2.4.24/include/linux/ext3_extents.h   2004-11-02 20:32:17.000000000 +0300
2564 @@ -0,0 +1,263 @@
2565 +/*
2566 + * Copyright (c) 2003, Cluster File Systems, Inc, info@clusterfs.com
2567 + * Written by Alex Tomas <alex@clusterfs.com>
2568 + *
2569 + * This program is free software; you can redistribute it and/or modify
2570 + * it under the terms of the GNU General Public License version 2 as
2571 + * published by the Free Software Foundation.
2572 + *
2573 + * This program is distributed in the hope that it will be useful,
2574 + * but WITHOUT ANY WARRANTY; without even the implied warranty of
2575 + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
2576 + * GNU General Public License for more details.
2577 + *
2578 + * You should have received a copy of the GNU General Public Licens
2579 + * along with this program; if not, write to the Free Software
2580 + * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-
2581 + */
2582 +
2583 +#ifndef _LINUX_EXT3_EXTENTS
2584 +#define _LINUX_EXT3_EXTENTS
2585 +
2586 +/*
2587 + * with AGRESSIVE_TEST defined capacity of index/leaf blocks
2588 + * become very little, so index split, in-depth growing and
2589 + * other hard changes happens much more often
2590 + * this is for debug purposes only
2591 + */
2592 +#define AGRESSIVE_TEST_
2593 +
2594 +/*
2595 + * if CHECK_BINSEARCH defined, then results of binary search
2596 + * will be checked by linear search
2597 + */
2598 +#define CHECK_BINSEARCH_
2599 +
2600 +/*
2601 + * if EXT_DEBUG is defined you can use 'extdebug' mount option
2602 + * to get lots of info what's going on
2603 + */
2604 +#define EXT_DEBUG_
2605 +#ifdef EXT_DEBUG
2606 +#define ext_debug(tree,fmt,a...)                       \
2607 +do {                                                   \
2608 +       if (test_opt((tree)->inode->i_sb, EXTDEBUG))    \
2609 +               printk(fmt, ##a);                       \
2610 +} while (0);
2611 +#else
2612 +#define ext_debug(tree,fmt,a...)
2613 +#endif
2614 +
2615 +/*
2616 + * if EXT_STATS is defined then stats numbers are collected
2617 + * these number will be displayed at umount time
2618 + */
2619 +#define EXT_STATS_
2620 +
2621 +
2622 +#define EXT3_ALLOC_NEEDED      3       /* block bitmap + group desc. + sb */
2623 +
2624 +/*
2625 + * ext3_inode has i_block array (total 60 bytes)
2626 + * first 4 bytes are used to store:
2627 + *  - tree depth (0 mean there is no tree yet. all extents in the inode)
2628 + *  - number of alive extents in the inode
2629 + */
2630 +
2631 +/*
2632 + * this is extent on-disk structure
2633 + * it's used at the bottom of the tree
2634 + */
2635 +struct ext3_extent {
2636 +       __u32   ee_block;       /* first logical block extent covers */
2637 +       __u16   ee_len;         /* number of blocks covered by extent */
2638 +       __u16   ee_start_hi;    /* high 16 bits of physical block */
2639 +       __u32   ee_start;       /* low 32 bigs of physical block */
2640 +};
2641 +
2642 +/*
2643 + * this is index on-disk structure
2644 + * it's used at all the levels, but the bottom
2645 + */
2646 +struct ext3_extent_idx {
2647 +       __u32   ei_block;       /* index covers logical blocks from 'block' */
2648 +       __u32   ei_leaf;        /* pointer to the physical block of the next *
2649 +                                * level. leaf or next index could bet here */
2650 +       __u16   ei_leaf_hi;     /* high 16 bits of physical block */
2651 +       __u16   ei_unused;
2652 +};
2653 +
2654 +/*
2655 + * each block (leaves and indexes), even inode-stored has header
2656 + */
2657 +struct ext3_extent_header {
2658 +       __u16   eh_magic;       /* probably will support different formats */
2659 +       __u16   eh_entries;     /* number of valid entries */
2660 +       __u16   eh_max;         /* capacity of store in entries */
2661 +       __u16   eh_depth;       /* has tree real underlaying blocks? */
2662 +       __u32   eh_generation;  /* generation of the tree */
2663 +};
2664 +
2665 +#define EXT3_EXT_MAGIC         0xf30a
2666 +
2667 +/*
2668 + * array of ext3_ext_path contains path to some extent
2669 + * creation/lookup routines use it for traversal/splitting/etc
2670 + * truncate uses it to simulate recursive walking
2671 + */
2672 +struct ext3_ext_path {
2673 +       __u32                           p_block;
2674 +       __u16                           p_depth;
2675 +       struct ext3_extent              *p_ext;
2676 +       struct ext3_extent_idx          *p_idx;
2677 +       struct ext3_extent_header       *p_hdr;
2678 +       struct buffer_head              *p_bh;
2679 +};
2680 +
2681 +/*
2682 + * structure for external API
2683 + */
2684 +
2685 +/*
2686 + * storage for cached extent
2687 + */
2688 +struct ext3_ext_cache {
2689 +       __u32   ec_start;
2690 +       __u32   ec_block;
2691 +       __u32   ec_len;
2692 +       __u32   ec_type;
2693 +};
2694 +
2695 +#define EXT3_EXT_CACHE_NO      0
2696 +#define EXT3_EXT_CACHE_GAP     1
2697 +#define EXT3_EXT_CACHE_EXTENT  2
2698 +
2699 +/*
2700 + * ext3_extents_tree is used to pass initial information
2701 + * to top-level extents API
2702 + */
2703 +struct ext3_extents_helpers;
2704 +struct ext3_extents_tree {
2705 +       struct inode *inode;    /* inode which tree belongs to */
2706 +       void *root;             /* ptr to data top of tree resides at */
2707 +       void *buffer;           /* will be passed as arg to ^^ routines */
2708 +       int buffer_len;
2709 +       void *private;
2710 +       struct ext3_ext_cache *cex;/* last found extent */
2711 +       struct ext3_extents_helpers *ops;
2712 +};
2713 +
2714 +struct ext3_extents_helpers {
2715 +       int (*get_write_access)(handle_t *h, void *buffer);
2716 +       int (*mark_buffer_dirty)(handle_t *h, void *buffer);
2717 +       int (*mergable)(struct ext3_extent *ex1, struct ext3_extent *ex2);
2718 +       int (*remove_extent_credits)(struct ext3_extents_tree *,
2719 +                                    struct ext3_extent *, unsigned long,
2720 +                                    unsigned long);
2721 +       int (*remove_extent)(struct ext3_extents_tree *,
2722 +                            struct ext3_extent *, unsigned long,
2723 +                            unsigned long);
2724 +       int (*new_block)(handle_t *, struct ext3_extents_tree *,
2725 +                        struct ext3_ext_path *, struct ext3_extent *,
2726 +                        int *);
2727 +};
2728 +
2729 +/*
2730 + * to be called by ext3_ext_walk_space()
2731 + * negative retcode - error
2732 + * positive retcode - signal for ext3_ext_walk_space(), see below
2733 + * callback must return valid extent (passed or newly created)
2734 + */
2735 +typedef int (*ext_prepare_callback)(struct ext3_extents_tree *,
2736 +                                   struct ext3_ext_path *,
2737 +                                   struct ext3_ext_cache *);
2738 +
2739 +#define EXT_CONTINUE   0
2740 +#define EXT_BREAK      1
2741 +#define EXT_REPEAT     2
2742 +
2743 +
2744 +#define EXT_MAX_BLOCK  0xffffffff
2745 +
2746 +
2747 +#define EXT_FIRST_EXTENT(__hdr__) \
2748 +       ((struct ext3_extent *) (((char *) (__hdr__)) +         \
2749 +                                sizeof(struct ext3_extent_header)))
2750 +#define EXT_FIRST_INDEX(__hdr__) \
2751 +       ((struct ext3_extent_idx *) (((char *) (__hdr__)) +     \
2752 +                                    sizeof(struct ext3_extent_header)))
2753 +#define EXT_HAS_FREE_INDEX(__path__) \
2754 +       ((__path__)->p_hdr->eh_entries < (__path__)->p_hdr->eh_max)
2755 +#define EXT_LAST_EXTENT(__hdr__) \
2756 +       (EXT_FIRST_EXTENT((__hdr__)) + (__hdr__)->eh_entries - 1)
2757 +#define EXT_LAST_INDEX(__hdr__) \
2758 +       (EXT_FIRST_INDEX((__hdr__)) + (__hdr__)->eh_entries - 1)
2759 +#define EXT_MAX_EXTENT(__hdr__) \
2760 +       (EXT_FIRST_EXTENT((__hdr__)) + (__hdr__)->eh_max - 1)
2761 +#define EXT_MAX_INDEX(__hdr__) \
2762 +       (EXT_FIRST_INDEX((__hdr__)) + (__hdr__)->eh_max - 1)
2763 +
2764 +#define EXT_ROOT_HDR(tree) \
2765 +       ((struct ext3_extent_header *) (tree)->root)
2766 +#define EXT_BLOCK_HDR(bh) \
2767 +       ((struct ext3_extent_header *) (bh)->b_data)
2768 +#define EXT_DEPTH(_t_) \
2769 +       (((struct ext3_extent_header *)((_t_)->root))->eh_depth)
2770 +#define EXT_GENERATION(_t_)    \
2771 +       (((struct ext3_extent_header *)((_t_)->root))->eh_generation)
2772 +
2773 +
2774 +#define EXT_ASSERT(__x__) if (!(__x__)) BUG();
2775 +
2776 +#define EXT_CHECK_PATH(tree,path)                                      \
2777 +{                                                                      \
2778 +       int depth = EXT_DEPTH(tree);                                    \
2779 +       BUG_ON((unsigned long) (path) < __PAGE_OFFSET);                 \
2780 +       BUG_ON((unsigned long) (path)[depth].p_idx <                    \
2781 +                       __PAGE_OFFSET && (path)[depth].p_idx != NULL);  \
2782 +       BUG_ON((unsigned long) (path)[depth].p_ext <                    \
2783 +                       __PAGE_OFFSET && (path)[depth].p_ext != NULL);  \
2784 +       BUG_ON((unsigned long) (path)[depth].p_hdr < __PAGE_OFFSET);    \
2785 +       BUG_ON((unsigned long) (path)[depth].p_bh < __PAGE_OFFSET       \
2786 +                       && depth != 0);                                 \
2787 +       BUG_ON((path)[0].p_depth != depth);                             \
2788 +}
2789 +
2790 +
2791 +/*
2792 + * this structure is used to gather extents from the tree via ioctl
2793 + */
2794 +struct ext3_extent_buf {
2795 +       unsigned long start;
2796 +       int buflen;
2797 +       void *buffer;
2798 +       void *cur;
2799 +       int err;
2800 +};
2801 +
2802 +/*
2803 + * this structure is used to collect stats info about the tree
2804 + */
2805 +struct ext3_extent_tree_stats {
2806 +       int depth;
2807 +       int extents_num;
2808 +       int leaf_num;
2809 +};
2810 +
2811 +extern void ext3_init_tree_desc(struct ext3_extents_tree *, struct inode *);
2812 +extern int ext3_extent_tree_init(handle_t *, struct ext3_extents_tree *);
2813 +extern int ext3_ext_calc_credits_for_insert(struct ext3_extents_tree *, struct ext3_ext_path *);
2814 +extern int ext3_ext_insert_extent(handle_t *, struct ext3_extents_tree *, struct ext3_ext_path *, struct ext3_extent *);
2815 +extern int ext3_ext_walk_space(struct ext3_extents_tree *, unsigned long, unsigned long, ext_prepare_callback);
2816 +extern int ext3_ext_remove_space(struct ext3_extents_tree *, unsigned long, unsigned long);
2817 +extern struct ext3_ext_path * ext3_ext_find_extent(struct ext3_extents_tree *, int, struct ext3_ext_path *);
2818 +
2819 +static inline void
2820 +ext3_ext_invalidate_cache(struct ext3_extents_tree *tree)
2821 +{
2822 +       if (tree->cex)
2823 +               tree->cex->ec_type = EXT3_EXT_CACHE_NO;
2824 +}
2825 +
2826 +
2827 +#endif /* _LINUX_EXT3_EXTENTS */
2828 Index: linux-2.4.24/include/linux/ext3_fs_i.h
2829 ===================================================================
2830 --- linux-2.4.24.orig/include/linux/ext3_fs_i.h 2004-11-02 20:28:32.000000000 +0300
2831 +++ linux-2.4.24/include/linux/ext3_fs_i.h      2004-11-02 20:43:45.000000000 +0300
2832 @@ -76,6 +76,8 @@
2833          * by other means, so we have truncate_sem.
2834          */
2835         struct rw_semaphore truncate_sem;
2836 +
2837 +       __u32 i_cached_extent[4];
2838  };
2839
2840  #endif /* _LINUX_EXT3_FS_I */