Whamcloud - gitweb
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authorscjody <scjody>
Thu, 15 Mar 2007 22:02:05 +0000 (22:02 +0000)
committerscjody <scjody>
Thu, 15 Mar 2007 22:02:05 +0000 (22:02 +0000)
b=11801
r=adilger
r=green

Fork ext3-extents-2.6.15.patch to apply to latest SLES 10 kernel.

ldiskfs/kernel_patches/patches/ext3-extents-2.6.16-sles10.patch [new file with mode: 0644]
ldiskfs/kernel_patches/series/ldiskfs-2.6-sles10.series
lustre/kernel_patches/patches/ext3-extents-2.6.16-sles10.patch [new file with mode: 0644]
lustre/kernel_patches/series/ldiskfs-2.6-sles10.series

diff --git a/ldiskfs/kernel_patches/patches/ext3-extents-2.6.16-sles10.patch b/ldiskfs/kernel_patches/patches/ext3-extents-2.6.16-sles10.patch
new file mode 100644 (file)
index 0000000..fd17dab
--- /dev/null
@@ -0,0 +1,2947 @@
+Index: linux-2.6.16.27-0.9/fs/ext3/extents.c
+===================================================================
+--- /dev/null
++++ linux-2.6.16.27-0.9/fs/ext3/extents.c
+@@ -0,0 +1,2359 @@
++/*
++ * Copyright(c) 2003, 2004, 2005, Cluster File Systems, Inc, info@clusterfs.com
++ * Written by Alex Tomas <alex@clusterfs.com>
++ *
++ * This program is free software; you can redistribute it and/or modify
++ * it under the terms of the GNU General Public License version 2 as
++ * published by the Free Software Foundation.
++ *
++ * This program is distributed in the hope that it will be useful,
++ * but WITHOUT ANY WARRANTY; without even the implied warranty of
++ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
++ * GNU General Public License for more details.
++ *
++ * You should have received a copy of the GNU General Public Licens
++ * along with this program; if not, write to the Free Software
++ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-
++ */
++
++/*
++ * Extents support for EXT3
++ *
++ * TODO:
++ *   - ext3_ext_walk_space() sould not use ext3_ext_find_extent()
++ *   - ext3_ext_calc_credits() could take 'mergable' into account
++ *   - ext3*_error() should be used in some situations
++ *   - find_goal() [to be tested and improved]
++ *   - smart tree reduction
++ *   - arch-independence
++ *     common on-disk format for big/little-endian arch
++ */
++
++#include <linux/module.h>
++#include <linux/fs.h>
++#include <linux/time.h>
++#include <linux/ext3_jbd.h>
++#include <linux/jbd.h>
++#include <linux/smp_lock.h>
++#include <linux/highuid.h>
++#include <linux/pagemap.h>
++#include <linux/quotaops.h>
++#include <linux/string.h>
++#include <linux/slab.h>
++#include <linux/ext3_extents.h>
++#include <asm/uaccess.h>
++
++
++static inline int ext3_ext_check_header(struct ext3_extent_header *eh)
++{
++      if (eh->eh_magic != EXT3_EXT_MAGIC) {
++              printk(KERN_ERR "EXT3-fs: invalid magic = 0x%x\n",
++                     (unsigned)eh->eh_magic);
++              return -EIO;
++      }
++      if (eh->eh_max == 0) {
++              printk(KERN_ERR "EXT3-fs: invalid eh_max = %u\n",
++                     (unsigned)eh->eh_max);
++              return -EIO;
++      }
++      if (eh->eh_entries > eh->eh_max) {
++              printk(KERN_ERR "EXT3-fs: invalid eh_entries = %u\n",
++                     (unsigned)eh->eh_entries);
++              return -EIO;
++      }
++      return 0;
++}
++
++static handle_t *ext3_ext_journal_restart(handle_t *handle, int needed)
++{
++      int err;
++
++      if (handle->h_buffer_credits > needed)
++              return handle;
++      if (!ext3_journal_extend(handle, needed))
++              return handle;
++      err = ext3_journal_restart(handle, needed);
++      
++      return handle;
++}
++
++static int inline
++ext3_ext_get_access_for_root(handle_t *h, struct ext3_extents_tree *tree)
++{
++      if (tree->ops->get_write_access)
++              return tree->ops->get_write_access(h,tree->buffer);
++      else
++              return 0;
++}
++
++static int inline
++ext3_ext_mark_root_dirty(handle_t *h, struct ext3_extents_tree *tree)
++{
++      if (tree->ops->mark_buffer_dirty)
++              return tree->ops->mark_buffer_dirty(h,tree->buffer);
++      else
++              return 0;
++}
++
++/*
++ * could return:
++ *  - EROFS
++ *  - ENOMEM
++ */
++static int ext3_ext_get_access(handle_t *handle,
++                             struct ext3_extents_tree *tree,
++                             struct ext3_ext_path *path)
++{
++      int err;
++
++      if (path->p_bh) {
++              /* path points to block */
++              err = ext3_journal_get_write_access(handle, path->p_bh);
++      } else {
++              /* path points to leaf/index in inode body */
++              err = ext3_ext_get_access_for_root(handle, tree);
++      }
++      return err;
++}
++
++/*
++ * could return:
++ *  - EROFS
++ *  - ENOMEM
++ *  - EIO
++ */
++static int ext3_ext_dirty(handle_t *handle, struct ext3_extents_tree *tree,
++                        struct ext3_ext_path *path)
++{
++      int err;
++      if (path->p_bh) {
++              /* path points to block */
++              err =ext3_journal_dirty_metadata(handle, path->p_bh);
++      } else {
++              /* path points to leaf/index in inode body */
++              err = ext3_ext_mark_root_dirty(handle, tree);
++      }
++      return err;
++}
++
++static int inline
++ext3_ext_new_block(handle_t *handle, struct ext3_extents_tree *tree,
++                 struct ext3_ext_path *path, struct ext3_extent *ex,
++                 int *err)
++{
++      int goal, depth, newblock;
++      struct inode *inode;
++
++      EXT_ASSERT(tree);
++      if (tree->ops->new_block)
++              return tree->ops->new_block(handle, tree, path, ex, err);
++
++      inode = tree->inode;
++      depth = EXT_DEPTH(tree);
++      if (path && depth > 0) {
++              goal = path[depth-1].p_block;
++      } else {
++              struct ext3_inode_info *ei = EXT3_I(inode);
++              unsigned long bg_start;
++              unsigned long colour;
++
++              bg_start = (ei->i_block_group *
++                          EXT3_BLOCKS_PER_GROUP(inode->i_sb)) +
++                      le32_to_cpu(EXT3_SB(inode->i_sb)->s_es->s_first_data_block);
++              colour = (current->pid % 16) *
++                      (EXT3_BLOCKS_PER_GROUP(inode->i_sb) / 16);
++              goal = bg_start + colour;
++      }
++
++      newblock = ext3_new_block(handle, inode, goal, err);
++      return newblock;
++}
++
++static inline void ext3_ext_tree_changed(struct ext3_extents_tree *tree)
++{
++      struct ext3_extent_header *neh = EXT_ROOT_HDR(tree);
++      neh->eh_generation = ((EXT_FLAGS(neh) & ~EXT_FLAGS_CLR_UNKNOWN) << 24) |
++                           (EXT_HDR_GEN(neh) + 1);
++}
++
++static inline int ext3_ext_space_block(struct ext3_extents_tree *tree)
++{
++      int size;
++
++      size = (tree->inode->i_sb->s_blocksize -
++              sizeof(struct ext3_extent_header)) /
++                              sizeof(struct ext3_extent);
++#ifdef AGRESSIVE_TEST
++      size = 6;
++#endif
++      return size;
++}
++
++static inline int ext3_ext_space_block_idx(struct ext3_extents_tree *tree)
++{
++      int size;
++
++      size = (tree->inode->i_sb->s_blocksize -
++              sizeof(struct ext3_extent_header)) /
++                              sizeof(struct ext3_extent_idx);
++#ifdef AGRESSIVE_TEST
++      size = 5;
++#endif
++      return size;
++}
++
++static inline int ext3_ext_space_root(struct ext3_extents_tree *tree)
++{
++      int size;
++
++      size = (tree->buffer_len - sizeof(struct ext3_extent_header)) /
++                      sizeof(struct ext3_extent);
++#ifdef AGRESSIVE_TEST
++      size = 3;
++#endif
++      return size;
++}
++
++static inline int ext3_ext_space_root_idx(struct ext3_extents_tree *tree)
++{
++      int size;
++
++      size = (tree->buffer_len - sizeof(struct ext3_extent_header)) /
++                      sizeof(struct ext3_extent_idx);
++#ifdef AGRESSIVE_TEST
++      size = 4;
++#endif
++      return size;
++}
++
++static void ext3_ext_show_path(struct ext3_extents_tree *tree,
++                             struct ext3_ext_path *path)
++{
++#ifdef EXT_DEBUG
++      int k, l = path->p_depth;
++
++      ext_debug(tree, "path:");
++      for (k = 0; k <= l; k++, path++) {
++              if (path->p_idx) {
++                      ext_debug(tree, "  %d->%d", path->p_idx->ei_block,
++                                path->p_idx->ei_leaf);
++              } else if (path->p_ext) {
++                      ext_debug(tree, "  %d:%d:%d",
++                                path->p_ext->ee_block,
++                                path->p_ext->ee_len,
++                                path->p_ext->ee_start);
++              } else
++                      ext_debug(tree, "  []");
++      }
++      ext_debug(tree, "\n");
++#endif
++}
++
++static void ext3_ext_show_leaf(struct ext3_extents_tree *tree,
++                             struct ext3_ext_path *path)
++{
++#ifdef EXT_DEBUG
++      int depth = EXT_DEPTH(tree);
++      struct ext3_extent_header *eh;
++      struct ext3_extent *ex;
++      int i;
++
++      if (!path)
++              return;
++
++      eh = path[depth].p_hdr;
++      ex = EXT_FIRST_EXTENT(eh);
++
++      for (i = 0; i < eh->eh_entries; i++, ex++) {
++              ext_debug(tree, "%d:%d:%d ",
++                        ex->ee_block, ex->ee_len, ex->ee_start);
++      }
++      ext_debug(tree, "\n");
++#endif
++}
++
++static void ext3_ext_drop_refs(struct ext3_ext_path *path)
++{
++      int depth = path->p_depth;
++      int i;
++
++      for (i = 0; i <= depth; i++, path++) {
++              if (path->p_bh) {
++                      brelse(path->p_bh);
++                      path->p_bh = NULL;
++              }
++      }
++}
++
++/*
++ * binary search for closest index by given block
++ */
++static inline void
++ext3_ext_binsearch_idx(struct ext3_extents_tree *tree,
++                     struct ext3_ext_path *path, int block)
++{
++      struct ext3_extent_header *eh = path->p_hdr;
++      struct ext3_extent_idx *ix;
++      int l = 0, k, r;
++
++      EXT_ASSERT(eh->eh_magic == EXT3_EXT_MAGIC);
++      EXT_ASSERT(eh->eh_entries <= eh->eh_max);
++      EXT_ASSERT(eh->eh_entries > 0);
++
++      ext_debug(tree, "binsearch for %d(idx):  ", block);
++
++      path->p_idx = ix = EXT_FIRST_INDEX(eh);
++
++      r = k = eh->eh_entries;
++      while (k > 1) {
++              k = (r - l) / 2;
++              if (block < ix[l + k].ei_block)
++                      r -= k;
++              else
++                      l += k;
++              ext_debug(tree, "%d:%d:%d ", k, l, r);
++      }
++
++      ix += l;
++      path->p_idx = ix;
++      ext_debug(tree," -> %d->%d ",path->p_idx->ei_block,path->p_idx->ei_leaf);
++
++      while (l++ < r) {
++              if (block < ix->ei_block) 
++                      break;
++              path->p_idx = ix++;
++      }
++      ext_debug(tree, "  -> %d->%d\n", path->p_idx->ei_block,
++                path->p_idx->ei_leaf);
++
++#ifdef CHECK_BINSEARCH 
++      {
++              struct ext3_extent_idx *chix;
++
++              chix = ix = EXT_FIRST_INDEX(eh);
++              for (k = 0; k < eh->eh_entries; k++, ix++) {
++                      if (k != 0 && ix->ei_block <= ix[-1].ei_block) {
++                              printk("k=%d, ix=0x%p, first=0x%p\n", k,
++                                     ix, EXT_FIRST_INDEX(eh));
++                              printk("%u <= %u\n",
++                                     ix->ei_block,ix[-1].ei_block);
++                      }
++                      EXT_ASSERT(k == 0 || ix->ei_block > ix[-1].ei_block);
++                      if (block < ix->ei_block) 
++                              break;
++                      chix = ix;
++              }
++              EXT_ASSERT(chix == path->p_idx);
++      }
++#endif
++}
++
++/*
++ * binary search for closest extent by given block
++ */
++static inline void
++ext3_ext_binsearch(struct ext3_extents_tree *tree,
++                 struct ext3_ext_path *path, int block)
++{
++      struct ext3_extent_header *eh = path->p_hdr;
++      struct ext3_extent *ex;
++      int l = 0, k, r;
++
++      EXT_ASSERT(eh->eh_magic == EXT3_EXT_MAGIC);
++      EXT_ASSERT(eh->eh_entries <= eh->eh_max);
++
++      if (eh->eh_entries == 0) {
++              /*
++               * this leaf is empty yet:
++               *  we get such a leaf in split/add case
++               */
++              return;
++      }
++      
++      ext_debug(tree, "binsearch for %d:  ", block);
++
++      path->p_ext = ex = EXT_FIRST_EXTENT(eh);
++
++      r = k = eh->eh_entries;
++      while (k > 1) {
++              k = (r - l) / 2;
++              if (block < ex[l + k].ee_block)
++                      r -= k;
++              else
++                      l += k;
++              ext_debug(tree, "%d:%d:%d ", k, l, r);
++      }
++
++      ex += l;
++      path->p_ext = ex;
++      ext_debug(tree, "  -> %d:%d:%d ", path->p_ext->ee_block,
++                path->p_ext->ee_start, path->p_ext->ee_len);
++
++      while (l++ < r) {
++              if (block < ex->ee_block) 
++                      break;
++              path->p_ext = ex++;
++      }
++      ext_debug(tree, "  -> %d:%d:%d\n", path->p_ext->ee_block,
++                path->p_ext->ee_start, path->p_ext->ee_len);
++
++#ifdef CHECK_BINSEARCH 
++      {
++              struct ext3_extent *chex;
++
++              chex = ex = EXT_FIRST_EXTENT(eh);
++              for (k = 0; k < eh->eh_entries; k++, ex++) {
++                      EXT_ASSERT(k == 0 || ex->ee_block > ex[-1].ee_block);
++                      if (block < ex->ee_block) 
++                              break;
++                      chex = ex;
++              }
++              EXT_ASSERT(chex == path->p_ext);
++      }
++#endif
++}
++
++int ext3_extent_tree_init(handle_t *handle, struct ext3_extents_tree *tree)
++{
++      struct ext3_extent_header *eh;
++
++      BUG_ON(tree->buffer_len == 0);
++      ext3_ext_get_access_for_root(handle, tree);
++      eh = EXT_ROOT_HDR(tree);
++      eh->eh_depth = 0;
++      eh->eh_entries = 0;
++      eh->eh_magic = EXT3_EXT_MAGIC;
++      eh->eh_max = ext3_ext_space_root(tree);
++      ext3_ext_mark_root_dirty(handle, tree);
++      ext3_ext_invalidate_cache(tree);
++      return 0;
++}
++
++struct ext3_ext_path *
++ext3_ext_find_extent(struct ext3_extents_tree *tree, int block,
++                   struct ext3_ext_path *path)
++{
++      struct ext3_extent_header *eh;
++      struct buffer_head *bh;
++      int depth, i, ppos = 0;
++
++      EXT_ASSERT(tree);
++      EXT_ASSERT(tree->inode);
++      EXT_ASSERT(tree->root);
++
++      eh = EXT_ROOT_HDR(tree);
++      EXT_ASSERT(eh);
++      if (ext3_ext_check_header(eh)) {
++              /* don't free previously allocated path
++               * -- caller should take care */
++              path = NULL;
++              goto err;
++      }
++
++      i = depth = EXT_DEPTH(tree);
++      EXT_ASSERT(eh->eh_max);
++      EXT_ASSERT(eh->eh_magic == EXT3_EXT_MAGIC);
++      
++      /* account possible depth increase */
++      if (!path) {
++              path = kmalloc(sizeof(struct ext3_ext_path) * (depth + 2),
++                             GFP_NOFS);
++              if (!path)
++                      return ERR_PTR(-ENOMEM);
++      }
++      memset(path, 0, sizeof(struct ext3_ext_path) * (depth + 1));
++      path[0].p_hdr = eh;
++
++      /* walk through the tree */
++      while (i) {
++              ext_debug(tree, "depth %d: num %d, max %d\n",
++                        ppos, eh->eh_entries, eh->eh_max);
++              ext3_ext_binsearch_idx(tree, path + ppos, block);
++              path[ppos].p_block = path[ppos].p_idx->ei_leaf;
++              path[ppos].p_depth = i;
++              path[ppos].p_ext = NULL;
++
++              bh = sb_bread(tree->inode->i_sb, path[ppos].p_block);
++              if (!bh)
++                      goto err;
++
++              eh = EXT_BLOCK_HDR(bh);
++              ppos++;
++              EXT_ASSERT(ppos <= depth);
++              path[ppos].p_bh = bh;
++              path[ppos].p_hdr = eh;
++              i--;
++
++              if (ext3_ext_check_header(eh))
++                      goto err;
++      }
++
++      path[ppos].p_depth = i;
++      path[ppos].p_hdr = eh;
++      path[ppos].p_ext = NULL;
++      path[ppos].p_idx = NULL;
++
++      if (ext3_ext_check_header(eh))
++              goto err;
++
++      /* find extent */
++      ext3_ext_binsearch(tree, path + ppos, block);
++
++      ext3_ext_show_path(tree, path);
++
++      return path;
++
++err:
++      printk(KERN_ERR "EXT3-fs: header is corrupted!\n");
++      if (path) {
++              ext3_ext_drop_refs(path);
++              kfree(path);
++      }
++      return ERR_PTR(-EIO);
++}
++
++/*
++ * insert new index [logical;ptr] into the block at cupr
++ * it check where to insert: before curp or after curp
++ */
++static int ext3_ext_insert_index(handle_t *handle,
++                               struct ext3_extents_tree *tree,
++                               struct ext3_ext_path *curp,
++                               int logical, int ptr)
++{
++      struct ext3_extent_idx *ix;
++      int len, err;
++
++      if ((err = ext3_ext_get_access(handle, tree, curp)))
++              return err;
++
++      EXT_ASSERT(logical != curp->p_idx->ei_block);
++      len = EXT_MAX_INDEX(curp->p_hdr) - curp->p_idx;
++      if (logical > curp->p_idx->ei_block) {
++              /* insert after */
++              if (curp->p_idx != EXT_LAST_INDEX(curp->p_hdr)) {
++                      len = (len - 1) * sizeof(struct ext3_extent_idx);
++                      len = len < 0 ? 0 : len;
++                      ext_debug(tree, "insert new index %d after: %d. "
++                                "move %d from 0x%p to 0x%p\n",
++                                logical, ptr, len,
++                                (curp->p_idx + 1), (curp->p_idx + 2));
++                      memmove(curp->p_idx + 2, curp->p_idx + 1, len);
++              }
++              ix = curp->p_idx + 1;
++      } else {
++              /* insert before */
++              len = len * sizeof(struct ext3_extent_idx);
++              len = len < 0 ? 0 : len;
++              ext_debug(tree, "insert new index %d before: %d. "
++                        "move %d from 0x%p to 0x%p\n",
++                        logical, ptr, len,
++                        curp->p_idx, (curp->p_idx + 1));
++              memmove(curp->p_idx + 1, curp->p_idx, len);
++              ix = curp->p_idx;
++      }
++
++      ix->ei_block = logical;
++      ix->ei_leaf = ptr;
++      ix->ei_leaf_hi = ix->ei_unused = 0;
++      curp->p_hdr->eh_entries++;
++
++      EXT_ASSERT(curp->p_hdr->eh_entries <= curp->p_hdr->eh_max);
++      EXT_ASSERT(ix <= EXT_LAST_INDEX(curp->p_hdr));
++
++      err = ext3_ext_dirty(handle, tree, curp);
++      ext3_std_error(tree->inode->i_sb, err);
++
++      return err;
++}
++
++/*
++ * routine inserts new subtree into the path, using free index entry
++ * at depth 'at:
++ *  - allocates all needed blocks (new leaf and all intermediate index blocks)
++ *  - makes decision where to split
++ *  - moves remaining extens and index entries (right to the split point)
++ *    into the newly allocated blocks
++ *  - initialize subtree
++ */
++static int ext3_ext_split(handle_t *handle, struct ext3_extents_tree *tree,
++                        struct ext3_ext_path *path,
++                        struct ext3_extent *newext, int at)
++{
++      struct buffer_head *bh = NULL;
++      int depth = EXT_DEPTH(tree);
++      struct ext3_extent_header *neh;
++      struct ext3_extent_idx *fidx;
++      struct ext3_extent *ex;
++      int i = at, k, m, a;
++      unsigned long newblock, oldblock, border;
++      int *ablocks = NULL; /* array of allocated blocks */
++      int err = 0;
++
++      /* make decision: where to split? */
++      /* FIXME: now desicion is simplest: at current extent */
++
++      /* if current leaf will be splitted, then we should use 
++       * border from split point */
++      EXT_ASSERT(path[depth].p_ext <= EXT_MAX_EXTENT(path[depth].p_hdr));
++      if (path[depth].p_ext != EXT_MAX_EXTENT(path[depth].p_hdr)) {
++              border = path[depth].p_ext[1].ee_block;
++              ext_debug(tree, "leaf will be splitted."
++                        " next leaf starts at %d\n",
++                        (int)border);
++      } else {
++              border = newext->ee_block;
++              ext_debug(tree, "leaf will be added."
++                        " next leaf starts at %d\n",
++                        (int)border);
++      }
++
++      /* 
++       * if error occurs, then we break processing
++       * and turn filesystem read-only. so, index won't
++       * be inserted and tree will be in consistent
++       * state. next mount will repair buffers too
++       */
++
++      /*
++       * get array to track all allocated blocks
++       * we need this to handle errors and free blocks
++       * upon them
++       */
++      ablocks = kmalloc(sizeof(unsigned long) * depth, GFP_NOFS);
++      if (!ablocks)
++              return -ENOMEM;
++      memset(ablocks, 0, sizeof(unsigned long) * depth);
++
++      /* allocate all needed blocks */
++      ext_debug(tree, "allocate %d blocks for indexes/leaf\n", depth - at);
++      for (a = 0; a < depth - at; a++) {
++              newblock = ext3_ext_new_block(handle, tree, path, newext, &err);
++              if (newblock == 0)
++                      goto cleanup;
++              ablocks[a] = newblock;
++      }
++
++      /* initialize new leaf */
++      newblock = ablocks[--a];
++      EXT_ASSERT(newblock);
++      bh = sb_getblk(tree->inode->i_sb, newblock);
++      if (!bh) {
++              err = -EIO;
++              goto cleanup;
++      }
++      lock_buffer(bh);
++
++      if ((err = ext3_journal_get_create_access(handle, bh)))
++              goto cleanup;
++
++      neh = EXT_BLOCK_HDR(bh);
++      neh->eh_entries = 0;
++      neh->eh_max = ext3_ext_space_block(tree);
++      neh->eh_magic = EXT3_EXT_MAGIC;
++      neh->eh_depth = 0;
++      ex = EXT_FIRST_EXTENT(neh);
++
++      /* move remain of path[depth] to the new leaf */
++      EXT_ASSERT(path[depth].p_hdr->eh_entries == path[depth].p_hdr->eh_max);
++      /* start copy from next extent */
++      /* TODO: we could do it by single memmove */
++      m = 0;
++      path[depth].p_ext++;
++      while (path[depth].p_ext <=
++                      EXT_MAX_EXTENT(path[depth].p_hdr)) {
++              ext_debug(tree, "move %d:%d:%d in new leaf %lu\n",
++                        path[depth].p_ext->ee_block,
++                        path[depth].p_ext->ee_start,
++                        path[depth].p_ext->ee_len,
++                        newblock);
++              memmove(ex++, path[depth].p_ext++, sizeof(struct ext3_extent));
++              neh->eh_entries++;
++              m++;
++      }
++      set_buffer_uptodate(bh);
++      unlock_buffer(bh);
++
++      if ((err = ext3_journal_dirty_metadata(handle, bh)))
++              goto cleanup;   
++      brelse(bh);
++      bh = NULL;
++
++      /* correct old leaf */
++      if (m) {
++              if ((err = ext3_ext_get_access(handle, tree, path + depth)))
++                      goto cleanup;
++              path[depth].p_hdr->eh_entries -= m;
++              if ((err = ext3_ext_dirty(handle, tree, path + depth)))
++                      goto cleanup;
++              
++      }
++
++      /* create intermediate indexes */
++      k = depth - at - 1;
++      EXT_ASSERT(k >= 0);
++      if (k)
++              ext_debug(tree, "create %d intermediate indices\n", k);
++      /* insert new index into current index block */
++      /* current depth stored in i var */
++      i = depth - 1;
++      while (k--) {
++              oldblock = newblock;
++              newblock = ablocks[--a];
++              bh = sb_getblk(tree->inode->i_sb, newblock);
++              if (!bh) {
++                      err = -EIO;
++                      goto cleanup;
++              }
++              lock_buffer(bh);
++
++              if ((err = ext3_journal_get_create_access(handle, bh)))
++                      goto cleanup;
++
++              neh = EXT_BLOCK_HDR(bh);
++              neh->eh_entries = 1;
++              neh->eh_magic = EXT3_EXT_MAGIC;
++              neh->eh_max = ext3_ext_space_block_idx(tree);
++              neh->eh_depth = depth - i; 
++              fidx = EXT_FIRST_INDEX(neh);
++              fidx->ei_block = border;
++              fidx->ei_leaf = oldblock;
++              fidx->ei_leaf_hi = fidx->ei_unused = 0;
++
++              ext_debug(tree, "int.index at %d (block %lu): %lu -> %lu\n",
++                        i, newblock, border, oldblock);
++              /* copy indexes */
++              m = 0;
++              path[i].p_idx++;
++
++              ext_debug(tree, "cur 0x%p, last 0x%p\n", path[i].p_idx,
++                        EXT_MAX_INDEX(path[i].p_hdr));
++              EXT_ASSERT(EXT_MAX_INDEX(path[i].p_hdr) ==
++                         EXT_LAST_INDEX(path[i].p_hdr));
++              while (path[i].p_idx <= EXT_MAX_INDEX(path[i].p_hdr)) {
++                      ext_debug(tree, "%d: move %d:%d in new index %lu\n",
++                                i, path[i].p_idx->ei_block,
++                                path[i].p_idx->ei_leaf, newblock);
++                      memmove(++fidx, path[i].p_idx++,
++                              sizeof(struct ext3_extent_idx));
++                      neh->eh_entries++;
++                      EXT_ASSERT(neh->eh_entries <= neh->eh_max);
++                      m++;
++              }
++              set_buffer_uptodate(bh);
++              unlock_buffer(bh);
++
++              if ((err = ext3_journal_dirty_metadata(handle, bh)))
++                      goto cleanup;
++              brelse(bh);
++              bh = NULL;
++
++              /* correct old index */
++              if (m) {
++                      err = ext3_ext_get_access(handle, tree, path + i);
++                      if (err)
++                              goto cleanup;
++                      path[i].p_hdr->eh_entries -= m;
++                      err = ext3_ext_dirty(handle, tree, path + i);
++                      if (err)
++                              goto cleanup;
++              }
++
++              i--;
++      }
++
++      /* insert new index */
++      if (!err)
++              err = ext3_ext_insert_index(handle, tree, path + at,
++                                          border, newblock);
++
++cleanup:
++      if (bh) {
++              if (buffer_locked(bh))
++                      unlock_buffer(bh);
++              brelse(bh);
++      }
++
++      if (err) {
++              /* free all allocated blocks in error case */
++              for (i = 0; i < depth; i++) {
++                      if (!ablocks[i])
++                              continue;
++                      ext3_free_blocks(handle, tree->inode, ablocks[i], 1);
++              }
++      }
++      kfree(ablocks);
++
++      return err;
++}
++
++/*
++ * routine implements tree growing procedure:
++ *  - allocates new block
++ *  - moves top-level data (index block or leaf) into the new block
++ *  - initialize new top-level, creating index that points to the
++ *    just created block
++ */
++static int ext3_ext_grow_indepth(handle_t *handle,
++                               struct ext3_extents_tree *tree,
++                               struct ext3_ext_path *path,
++                               struct ext3_extent *newext)
++{
++      struct ext3_ext_path *curp = path;
++      struct ext3_extent_header *neh;
++      struct ext3_extent_idx *fidx;
++      struct buffer_head *bh;
++      unsigned long newblock;
++      int err = 0;
++
++      newblock = ext3_ext_new_block(handle, tree, path, newext, &err);
++      if (newblock == 0)
++              return err;
++
++      bh = sb_getblk(tree->inode->i_sb, newblock);
++      if (!bh) {
++              err = -EIO;
++              ext3_std_error(tree->inode->i_sb, err);
++              return err;
++      }
++      lock_buffer(bh);
++
++      if ((err = ext3_journal_get_create_access(handle, bh))) {
++              unlock_buffer(bh);
++              goto out;       
++      }
++
++      /* move top-level index/leaf into new block */
++      memmove(bh->b_data, curp->p_hdr, tree->buffer_len);
++
++      /* set size of new block */
++      neh = EXT_BLOCK_HDR(bh);
++      /* old root could have indexes or leaves
++       * so calculate eh_max right way */
++      if (EXT_DEPTH(tree))
++              neh->eh_max = ext3_ext_space_block_idx(tree);
++      else
++              neh->eh_max = ext3_ext_space_block(tree);
++      neh->eh_magic = EXT3_EXT_MAGIC;
++      set_buffer_uptodate(bh);
++      unlock_buffer(bh);
++
++      if ((err = ext3_journal_dirty_metadata(handle, bh)))
++              goto out;
++
++      /* create index in new top-level index: num,max,pointer */
++      if ((err = ext3_ext_get_access(handle, tree, curp)))
++              goto out;
++
++      curp->p_hdr->eh_magic = EXT3_EXT_MAGIC;
++      curp->p_hdr->eh_max = ext3_ext_space_root_idx(tree);
++      curp->p_hdr->eh_entries = 1;
++      curp->p_idx = EXT_FIRST_INDEX(curp->p_hdr);
++      /* FIXME: it works, but actually path[0] can be index */
++      curp->p_idx->ei_block = EXT_FIRST_EXTENT(path[0].p_hdr)->ee_block;
++      curp->p_idx->ei_leaf = newblock;
++      curp->p_idx->ei_leaf_hi = curp->p_idx->ei_unused = 0;
++
++      neh = EXT_ROOT_HDR(tree);
++      fidx = EXT_FIRST_INDEX(neh);
++      ext_debug(tree, "new root: num %d(%d), lblock %d, ptr %d\n",
++                neh->eh_entries, neh->eh_max, fidx->ei_block, fidx->ei_leaf); 
++
++      neh->eh_depth = path->p_depth + 1;
++      err = ext3_ext_dirty(handle, tree, curp);
++out:
++      brelse(bh);
++
++      return err;
++}
++
++/*
++ * routine finds empty index and adds new leaf. if no free index found
++ * then it requests in-depth growing
++ */
++static int ext3_ext_create_new_leaf(handle_t *handle,
++                                  struct ext3_extents_tree *tree,
++                                  struct ext3_ext_path *path,
++                                  struct ext3_extent *newext)
++{
++      struct ext3_ext_path *curp;
++      int depth, i, err = 0;
++
++repeat:
++      i = depth = EXT_DEPTH(tree);
++      
++      /* walk up to the tree and look for free index entry */
++      curp = path + depth;
++      while (i > 0 && !EXT_HAS_FREE_INDEX(curp)) {
++              i--;
++              curp--;
++      }
++
++      /* we use already allocated block for index block
++       * so, subsequent data blocks should be contigoues */
++      if (EXT_HAS_FREE_INDEX(curp)) {
++              /* if we found index with free entry, then use that
++               * entry: create all needed subtree and add new leaf */
++              err = ext3_ext_split(handle, tree, path, newext, i);
++
++              /* refill path */
++              ext3_ext_drop_refs(path);
++              path = ext3_ext_find_extent(tree, newext->ee_block, path);
++              if (IS_ERR(path))
++                      err = PTR_ERR(path);
++      } else {
++              /* tree is full, time to grow in depth */
++              err = ext3_ext_grow_indepth(handle, tree, path, newext);
++
++              /* refill path */
++              ext3_ext_drop_refs(path);
++              path = ext3_ext_find_extent(tree, newext->ee_block, path);
++              if (IS_ERR(path))
++                      err = PTR_ERR(path);
++
++              /*
++               * only first (depth 0 -> 1) produces free space
++               * in all other cases we have to split growed tree
++               */
++              depth = EXT_DEPTH(tree);
++              if (path[depth].p_hdr->eh_entries == path[depth].p_hdr->eh_max) {
++                      /* now we need split */
++                      goto repeat;
++              }
++      }
++
++      if (err)
++              return err;
++
++      return 0;
++}
++
++/*
++ * returns allocated block in subsequent extent or EXT_MAX_BLOCK
++ * NOTE: it consider block number from index entry as
++ * allocated block. thus, index entries have to be consistent
++ * with leafs
++ */
++static unsigned long
++ext3_ext_next_allocated_block(struct ext3_ext_path *path)
++{
++      int depth;
++
++      EXT_ASSERT(path != NULL);
++      depth = path->p_depth;
++
++      if (depth == 0 && path->p_ext == NULL)
++              return EXT_MAX_BLOCK;
++
++      /* FIXME: what if index isn't full ?! */
++      while (depth >= 0) {
++              if (depth == path->p_depth) {
++                      /* leaf */
++                      if (path[depth].p_ext !=
++                          EXT_LAST_EXTENT(path[depth].p_hdr))
++                              return path[depth].p_ext[1].ee_block;
++              } else {
++                      /* index */
++                      if (path[depth].p_idx !=
++                          EXT_LAST_INDEX(path[depth].p_hdr))
++                              return path[depth].p_idx[1].ei_block;
++              }
++              depth--;        
++      }
++
++      return EXT_MAX_BLOCK;
++}
++
++/*
++ * returns first allocated block from next leaf or EXT_MAX_BLOCK
++ */
++static unsigned ext3_ext_next_leaf_block(struct ext3_extents_tree *tree,
++                                       struct ext3_ext_path *path)
++{
++      int depth;
++
++      EXT_ASSERT(path != NULL);
++      depth = path->p_depth;
++
++      /* zero-tree has no leaf blocks at all */
++      if (depth == 0)
++              return EXT_MAX_BLOCK;
++
++      /* go to index block */
++      depth--;
++      
++      while (depth >= 0) {
++              if (path[depth].p_idx !=
++                  EXT_LAST_INDEX(path[depth].p_hdr))
++                      return path[depth].p_idx[1].ei_block;
++              depth--;        
++      }
++
++      return EXT_MAX_BLOCK;
++}
++
++/*
++ * if leaf gets modified and modified extent is first in the leaf
++ * then we have to correct all indexes above
++ * TODO: do we need to correct tree in all cases?
++ */
++int ext3_ext_correct_indexes(handle_t *handle, struct ext3_extents_tree *tree,
++                           struct ext3_ext_path *path)
++{
++      struct ext3_extent_header *eh;
++      int depth = EXT_DEPTH(tree);    
++      struct ext3_extent *ex;
++      unsigned long border;
++      int k, err = 0;
++      
++      eh = path[depth].p_hdr;
++      ex = path[depth].p_ext;
++      EXT_ASSERT(ex);
++      EXT_ASSERT(eh);
++      
++      if (depth == 0) {
++              /* there is no tree at all */
++              return 0;
++      }
++      
++      if (ex != EXT_FIRST_EXTENT(eh)) {
++              /* we correct tree if first leaf got modified only */
++              return 0;
++      }
++      
++      /*
++       * TODO: we need correction if border is smaller then current one
++       */
++      k = depth - 1;
++      border = path[depth].p_ext->ee_block;
++      if ((err = ext3_ext_get_access(handle, tree, path + k)))
++              return err;
++      path[k].p_idx->ei_block = border;
++      if ((err = ext3_ext_dirty(handle, tree, path + k)))
++              return err;
++
++      while (k--) {
++              /* change all left-side indexes */
++              if (path[k+1].p_idx != EXT_FIRST_INDEX(path[k+1].p_hdr))
++                      break;
++              if ((err = ext3_ext_get_access(handle, tree, path + k)))
++                      break;
++              path[k].p_idx->ei_block = border;
++              if ((err = ext3_ext_dirty(handle, tree, path + k)))
++                      break;
++      }
++
++      return err;
++}
++
++static int inline
++ext3_can_extents_be_merged(struct ext3_extents_tree *tree,
++                         struct ext3_extent *ex1,
++                         struct ext3_extent *ex2)
++{
++      if (ex1->ee_block + ex1->ee_len != ex2->ee_block)
++              return 0;
++
++#ifdef AGRESSIVE_TEST
++      if (ex1->ee_len >= 4)
++              return 0;
++#endif
++
++      if (!tree->ops->mergable)
++              return 1;
++
++      return tree->ops->mergable(ex1, ex2);
++}
++
++/*
++ * this routine tries to merge requsted extent into the existing
++ * extent or inserts requested extent as new one into the tree,
++ * creating new leaf in no-space case
++ */
++int ext3_ext_insert_extent(handle_t *handle, struct ext3_extents_tree *tree,
++                         struct ext3_ext_path *path,
++                         struct ext3_extent *newext)
++{
++      struct ext3_extent_header * eh;
++      struct ext3_extent *ex, *fex;
++      struct ext3_extent *nearex; /* nearest extent */
++      struct ext3_ext_path *npath = NULL;
++      int depth, len, err, next;
++
++      EXT_ASSERT(newext->ee_len > 0);
++      depth = EXT_DEPTH(tree);
++      ex = path[depth].p_ext;
++      EXT_ASSERT(path[depth].p_hdr);
++
++      /* try to insert block into found extent and return */
++      if (ex && ext3_can_extents_be_merged(tree, ex, newext)) {
++              ext_debug(tree, "append %d block to %d:%d (from %d)\n",
++                        newext->ee_len, ex->ee_block, ex->ee_len,
++                        ex->ee_start);
++              if ((err = ext3_ext_get_access(handle, tree, path + depth)))
++                      return err;
++              ex->ee_len += newext->ee_len;
++              eh = path[depth].p_hdr;
++              nearex = ex;
++              goto merge;
++      }
++
++repeat:
++      depth = EXT_DEPTH(tree);
++      eh = path[depth].p_hdr;
++      if (eh->eh_entries < eh->eh_max)
++              goto has_space;
++
++      /* probably next leaf has space for us? */
++      fex = EXT_LAST_EXTENT(eh);
++      next = ext3_ext_next_leaf_block(tree, path);
++      if (newext->ee_block > fex->ee_block && next != EXT_MAX_BLOCK) {
++              ext_debug(tree, "next leaf block - %d\n", next);
++              EXT_ASSERT(!npath);
++              npath = ext3_ext_find_extent(tree, next, NULL);
++              if (IS_ERR(npath))
++                      return PTR_ERR(npath);
++              EXT_ASSERT(npath->p_depth == path->p_depth);
++              eh = npath[depth].p_hdr;
++              if (eh->eh_entries < eh->eh_max) {
++                      ext_debug(tree, "next leaf isnt full(%d)\n",
++                                eh->eh_entries);
++                      path = npath;
++                      goto repeat;
++              }
++              ext_debug(tree, "next leaf hasno free space(%d,%d)\n",
++                        eh->eh_entries, eh->eh_max);
++      }
++
++      /*
++       * there is no free space in found leaf
++       * we're gonna add new leaf in the tree
++       */
++      err = ext3_ext_create_new_leaf(handle, tree, path, newext);
++      if (err)
++              goto cleanup;
++      depth = EXT_DEPTH(tree);
++      eh = path[depth].p_hdr;
++
++has_space:
++      nearex = path[depth].p_ext;
++
++      if ((err = ext3_ext_get_access(handle, tree, path + depth)))
++              goto cleanup;
++
++      if (!nearex) {
++              /* there is no extent in this leaf, create first one */
++              ext_debug(tree, "first extent in the leaf: %d:%d:%d\n",
++                        newext->ee_block, newext->ee_start,
++                        newext->ee_len);
++              path[depth].p_ext = EXT_FIRST_EXTENT(eh);
++      } else if (newext->ee_block > nearex->ee_block) {
++              EXT_ASSERT(newext->ee_block != nearex->ee_block);
++              if (nearex != EXT_LAST_EXTENT(eh)) {
++                      len = EXT_MAX_EXTENT(eh) - nearex;
++                      len = (len - 1) * sizeof(struct ext3_extent);
++                      len = len < 0 ? 0 : len;
++                      ext_debug(tree, "insert %d:%d:%d after: nearest 0x%p, "
++                                "move %d from 0x%p to 0x%p\n",
++                                newext->ee_block, newext->ee_start,
++                                newext->ee_len,
++                                nearex, len, nearex + 1, nearex + 2);
++                      memmove(nearex + 2, nearex + 1, len);
++              }
++              path[depth].p_ext = nearex + 1;
++      } else {
++              EXT_ASSERT(newext->ee_block != nearex->ee_block);
++              len = (EXT_MAX_EXTENT(eh) - nearex) * sizeof(struct ext3_extent);
++              len = len < 0 ? 0 : len;
++              ext_debug(tree, "insert %d:%d:%d before: nearest 0x%p, "
++                        "move %d from 0x%p to 0x%p\n",
++                        newext->ee_block, newext->ee_start, newext->ee_len,
++                        nearex, len, nearex + 1, nearex + 2);
++              memmove(nearex + 1, nearex, len);
++              path[depth].p_ext = nearex;
++      }
++
++      eh->eh_entries++;
++      nearex = path[depth].p_ext;
++      nearex->ee_block = newext->ee_block;
++      nearex->ee_start = newext->ee_start;
++      nearex->ee_len = newext->ee_len;
++      /* FIXME: support for large fs */
++      nearex->ee_start_hi = 0;
++
++merge:
++      /* try to merge extents to the right */
++      while (nearex < EXT_LAST_EXTENT(eh)) {
++              if (!ext3_can_extents_be_merged(tree, nearex, nearex + 1))
++                      break;
++              /* merge with next extent! */
++              nearex->ee_len += nearex[1].ee_len;
++              if (nearex + 1 < EXT_LAST_EXTENT(eh)) {
++                      len = (EXT_LAST_EXTENT(eh) - nearex - 1) *
++                              sizeof(struct ext3_extent);
++                      memmove(nearex + 1, nearex + 2, len);
++              }
++              eh->eh_entries--;
++              EXT_ASSERT(eh->eh_entries > 0);
++      }
++
++      /* try to merge extents to the left */
++
++      /* time to correct all indexes above */
++      err = ext3_ext_correct_indexes(handle, tree, path);
++      if (err)
++              goto cleanup;
++
++      err = ext3_ext_dirty(handle, tree, path + depth);
++
++cleanup:
++      if (npath) {
++              ext3_ext_drop_refs(npath);
++              kfree(npath);
++      }
++      ext3_ext_tree_changed(tree);
++      ext3_ext_invalidate_cache(tree);
++      return err;
++}
++
++int ext3_ext_walk_space(struct ext3_extents_tree *tree, unsigned long block,
++                      unsigned long num, ext_prepare_callback func)
++{
++      struct ext3_ext_path *path = NULL;
++      struct ext3_ext_cache cbex;
++      struct ext3_extent *ex;
++      unsigned long next, start = 0, end = 0;
++      unsigned long last = block + num;
++      int depth, exists, err = 0;
++
++      EXT_ASSERT(tree);
++      EXT_ASSERT(func);
++      EXT_ASSERT(tree->inode);
++      EXT_ASSERT(tree->root);
++
++      while (block < last && block != EXT_MAX_BLOCK) {
++              num = last - block;
++              /* find extent for this block */
++              path = ext3_ext_find_extent(tree, block, path);
++              if (IS_ERR(path)) {
++                      err = PTR_ERR(path);
++                      path = NULL;
++                      break;
++              }
++
++              depth = EXT_DEPTH(tree);
++              EXT_ASSERT(path[depth].p_hdr);
++              ex = path[depth].p_ext;
++              next = ext3_ext_next_allocated_block(path);
++
++              exists = 0;
++              if (!ex) {
++                      /* there is no extent yet, so try to allocate
++                       * all requested space */
++                      start = block;
++                      end = block + num;
++              } else if (ex->ee_block > block) {
++                      /* need to allocate space before found extent */
++                      start = block;
++                      end = ex->ee_block;
++                      if (block + num < end)
++                              end = block + num;
++              } else if (block >= ex->ee_block + ex->ee_len) {
++                      /* need to allocate space after found extent */
++                      start = block;
++                      end = block + num;
++                      if (end >= next)
++                              end = next;
++              } else if (block >= ex->ee_block) {
++                      /* 
++                       * some part of requested space is covered
++                       * by found extent
++                       */
++                      start = block;
++                      end = ex->ee_block + ex->ee_len;
++                      if (block + num < end)
++                              end = block + num;
++                      exists = 1;
++              } else {
++                      BUG();
++              }
++              EXT_ASSERT(end > start);
++
++              if (!exists) {
++                      cbex.ec_block = start;
++                      cbex.ec_len = end - start;
++                      cbex.ec_start = 0;
++                      cbex.ec_type = EXT3_EXT_CACHE_GAP;
++              } else {
++                      cbex.ec_block = ex->ee_block;
++                      cbex.ec_len = ex->ee_len;
++                      cbex.ec_start = ex->ee_start;
++                      cbex.ec_type = EXT3_EXT_CACHE_EXTENT;
++              }
++
++              EXT_ASSERT(cbex.ec_len > 0);
++              EXT_ASSERT(path[depth].p_hdr);
++              err = func(tree, path, &cbex);
++              ext3_ext_drop_refs(path);
++
++              if (err < 0)
++                      break;
++              if (err == EXT_REPEAT)
++                      continue;
++              else if (err == EXT_BREAK) {
++                      err = 0;
++                      break;
++              }
++
++              if (EXT_DEPTH(tree) != depth) {
++                      /* depth was changed. we have to realloc path */
++                      kfree(path);
++                      path = NULL;
++              }
++
++              block = cbex.ec_block + cbex.ec_len;
++      }
++
++      if (path) {
++              ext3_ext_drop_refs(path);
++              kfree(path);
++      }
++
++      return err;
++}
++
++static inline void
++ext3_ext_put_in_cache(struct ext3_extents_tree *tree, __u32 block,
++                    __u32 len, __u32 start, int type)
++{
++      EXT_ASSERT(len > 0);
++      if (tree->cex) {
++              tree->cex->ec_type = type;
++              tree->cex->ec_block = block;
++              tree->cex->ec_len = len;
++              tree->cex->ec_start = start;
++      }
++}
++
++/*
++ * this routine calculate boundaries of the gap requested block fits into
++ * and cache this gap
++ */
++static inline void
++ext3_ext_put_gap_in_cache(struct ext3_extents_tree *tree,
++                        struct ext3_ext_path *path,
++                        unsigned long block)
++{
++      int depth = EXT_DEPTH(tree);
++      unsigned long lblock, len;
++      struct ext3_extent *ex;
++
++      if (!tree->cex)
++              return;
++
++      ex = path[depth].p_ext;
++      if (ex == NULL) {
++              /* there is no extent yet, so gap is [0;-] */
++              lblock = 0;
++              len = EXT_MAX_BLOCK;
++              ext_debug(tree, "cache gap(whole file):");
++      } else if (block < ex->ee_block) {
++              lblock = block;
++              len = ex->ee_block - block;
++              ext_debug(tree, "cache gap(before): %lu [%lu:%lu]",
++                        (unsigned long) block,
++                        (unsigned long) ex->ee_block,
++                        (unsigned long) ex->ee_len);
++      } else if (block >= ex->ee_block + ex->ee_len) {
++              lblock = ex->ee_block + ex->ee_len;
++              len = ext3_ext_next_allocated_block(path);
++              ext_debug(tree, "cache gap(after): [%lu:%lu] %lu",
++                        (unsigned long) ex->ee_block,
++                        (unsigned long) ex->ee_len,
++                        (unsigned long) block);
++              EXT_ASSERT(len > lblock);
++              len = len - lblock;
++      } else {
++              lblock = len = 0;
++              BUG();
++      }
++
++      ext_debug(tree, " -> %lu:%lu\n", (unsigned long) lblock, len);
++      ext3_ext_put_in_cache(tree, lblock, len, 0, EXT3_EXT_CACHE_GAP);
++}
++
++static inline int
++ext3_ext_in_cache(struct ext3_extents_tree *tree, unsigned long block,
++                struct ext3_extent *ex)
++{
++      struct ext3_ext_cache *cex = tree->cex;
++
++      /* is there cache storage at all? */
++      if (!cex)
++              return EXT3_EXT_CACHE_NO;
++
++      /* has cache valid data? */
++      if (cex->ec_type == EXT3_EXT_CACHE_NO)
++              return EXT3_EXT_CACHE_NO;
++
++      EXT_ASSERT(cex->ec_type == EXT3_EXT_CACHE_GAP ||
++                 cex->ec_type == EXT3_EXT_CACHE_EXTENT);
++      if (block >= cex->ec_block && block < cex->ec_block + cex->ec_len) {
++              ex->ee_block = cex->ec_block;
++              ex->ee_start = cex->ec_start;
++              ex->ee_start_hi = 0;
++              ex->ee_len = cex->ec_len;
++              ext_debug(tree, "%lu cached by %lu:%lu:%lu\n",
++                        (unsigned long) block,
++                        (unsigned long) ex->ee_block,
++                        (unsigned long) ex->ee_len,
++                        (unsigned long) ex->ee_start);
++              return cex->ec_type;
++      }
++
++      /* not in cache */
++      return EXT3_EXT_CACHE_NO;
++}
++
++/*
++ * routine removes index from the index block
++ * it's used in truncate case only. thus all requests are for
++ * last index in the block only
++ */
++int ext3_ext_rm_idx(handle_t *handle, struct ext3_extents_tree *tree,
++                  struct ext3_ext_path *path)
++{
++      struct buffer_head *bh;
++      int err;
++      
++      /* free index block */
++      path--;
++      EXT_ASSERT(path->p_hdr->eh_entries);
++      if ((err = ext3_ext_get_access(handle, tree, path)))
++              return err;
++      path->p_hdr->eh_entries--;
++      if ((err = ext3_ext_dirty(handle, tree, path)))
++              return err;
++      ext_debug(tree, "index is empty, remove it, free block %d\n",
++                path->p_idx->ei_leaf);
++      bh = sb_find_get_block(tree->inode->i_sb, path->p_idx->ei_leaf);
++      ext3_forget(handle, 1, tree->inode, bh, path->p_idx->ei_leaf);
++      ext3_free_blocks(handle, tree->inode, path->p_idx->ei_leaf, 1);
++      return err;
++}
++
++int ext3_ext_calc_credits_for_insert(struct ext3_extents_tree *tree,
++                                   struct ext3_ext_path *path)
++{
++      int depth = EXT_DEPTH(tree);
++      int needed;
++
++      if (path) {
++              /* probably there is space in leaf? */
++              if (path[depth].p_hdr->eh_entries < path[depth].p_hdr->eh_max)
++                      return 1;
++      }
++      
++      /*
++       * the worste case we're expecting is creation of the
++       * new root (growing in depth) with index splitting
++       * for splitting we have to consider depth + 1 because
++       * previous growing could increase it
++       */
++      depth = depth + 1;
++
++      /* 
++       * growing in depth:
++       * block allocation + new root + old root
++       */
++      needed = EXT3_ALLOC_NEEDED + 2;
++
++      /* index split. we may need:
++       *   allocate intermediate indexes and new leaf
++       *   change two blocks at each level, but root
++       *   modify root block (inode)
++       */
++      needed += (depth * EXT3_ALLOC_NEEDED) + (2 * depth) + 1;
++
++      return needed;
++}
++
++static int
++ext3_ext_split_for_rm(handle_t *handle, struct ext3_extents_tree *tree,
++                    struct ext3_ext_path *path, unsigned long start,
++                    unsigned long end)
++{
++      struct ext3_extent *ex, tex;
++      struct ext3_ext_path *npath;
++      int depth, creds, err;
++
++      depth = EXT_DEPTH(tree);
++      ex = path[depth].p_ext;
++      EXT_ASSERT(ex);
++      EXT_ASSERT(end < ex->ee_block + ex->ee_len - 1);
++      EXT_ASSERT(ex->ee_block < start);
++
++      /* calculate tail extent */
++      tex.ee_block = end + 1;
++      EXT_ASSERT(tex.ee_block < ex->ee_block + ex->ee_len);
++      tex.ee_len = ex->ee_block + ex->ee_len - tex.ee_block;
++
++      creds = ext3_ext_calc_credits_for_insert(tree, path);
++      handle = ext3_ext_journal_restart(handle, creds);
++      if (IS_ERR(handle))
++              return PTR_ERR(handle);
++      
++      /* calculate head extent. use primary extent */
++      err = ext3_ext_get_access(handle, tree, path + depth);
++      if (err)
++              return err;
++      ex->ee_len = start - ex->ee_block;
++      err = ext3_ext_dirty(handle, tree, path + depth);
++      if (err)
++              return err;
++
++      /* FIXME: some callback to free underlying resource
++       * and correct ee_start? */
++      ext_debug(tree, "split extent: head %u:%u, tail %u:%u\n",
++                ex->ee_block, ex->ee_len, tex.ee_block, tex.ee_len);
++
++      npath = ext3_ext_find_extent(tree, ex->ee_block, NULL);
++      if (IS_ERR(npath))
++              return PTR_ERR(npath);
++      depth = EXT_DEPTH(tree);
++      EXT_ASSERT(npath[depth].p_ext->ee_block == ex->ee_block);
++      EXT_ASSERT(npath[depth].p_ext->ee_len == ex->ee_len);
++
++      err = ext3_ext_insert_extent(handle, tree, npath, &tex);
++      ext3_ext_drop_refs(npath);
++      kfree(npath);
++
++      return err;
++}
++
++static int
++ext3_ext_rm_leaf(handle_t *handle, struct ext3_extents_tree *tree,
++               struct ext3_ext_path *path, unsigned long start,
++               unsigned long end)
++{
++      struct ext3_extent *ex, *fu = NULL, *lu, *le;
++      int err = 0, correct_index = 0;
++      int depth = EXT_DEPTH(tree), credits;
++      struct ext3_extent_header *eh;
++      unsigned a, b, block, num;
++
++      ext_debug(tree, "remove [%lu:%lu] in leaf\n", start, end);
++      if (!path[depth].p_hdr)
++              path[depth].p_hdr = EXT_BLOCK_HDR(path[depth].p_bh);
++      eh = path[depth].p_hdr;
++      EXT_ASSERT(eh);
++      EXT_ASSERT(eh->eh_entries <= eh->eh_max);
++      EXT_ASSERT(eh->eh_magic == EXT3_EXT_MAGIC);
++      
++      /* find where to start removing */
++      le = ex = EXT_LAST_EXTENT(eh);
++      while (ex != EXT_FIRST_EXTENT(eh)) {
++              if (ex->ee_block <= end)
++                      break;
++              ex--;
++      }
++
++      if (start > ex->ee_block && end < ex->ee_block + ex->ee_len - 1) {
++              /* removal of internal part of the extent requested
++               * tail and head must be placed in different extent
++               * so, we have to insert one more extent */
++              path[depth].p_ext = ex;
++              return ext3_ext_split_for_rm(handle, tree, path, start, end);
++      }
++      
++      lu = ex;
++      while (ex >= EXT_FIRST_EXTENT(eh) && ex->ee_block + ex->ee_len > start) {
++              ext_debug(tree, "remove ext %u:%u\n", ex->ee_block, ex->ee_len);
++              path[depth].p_ext = ex;
++      
++              a = ex->ee_block > start ? ex->ee_block : start;
++              b = ex->ee_block + ex->ee_len - 1 < end ?
++                      ex->ee_block + ex->ee_len - 1 : end;
++              
++              ext_debug(tree, "  border %u:%u\n", a, b);
++
++              if (a != ex->ee_block && b != ex->ee_block + ex->ee_len - 1) {
++                      block = 0;
++                      num = 0;
++                      BUG();
++              } else if (a != ex->ee_block) {
++                      /* remove tail of the extent */
++                      block = ex->ee_block;
++                      num = a - block;
++              } else if (b != ex->ee_block + ex->ee_len - 1) {
++                      /* remove head of the extent */
++                      block = a;
++                      num = b - a;
++              } else {
++                      /* remove whole extent: excelent! */
++                      block = ex->ee_block; 
++                      num = 0;
++                      EXT_ASSERT(a == ex->ee_block &&
++                                 b == ex->ee_block + ex->ee_len - 1);
++              }
++
++              if (ex == EXT_FIRST_EXTENT(eh))
++                      correct_index = 1;
++
++              credits = 1;
++              if (correct_index)
++                      credits += (EXT_DEPTH(tree) * EXT3_ALLOC_NEEDED) + 1;
++              if (tree->ops->remove_extent_credits)
++                      credits+=tree->ops->remove_extent_credits(tree,ex,a,b);
++              
++              handle = ext3_ext_journal_restart(handle, credits);
++              if (IS_ERR(handle)) {
++                      err = PTR_ERR(handle);
++                      goto out;
++              }
++
++              err = ext3_ext_get_access(handle, tree, path + depth);
++              if (err)
++                      goto out;
++
++              if (tree->ops->remove_extent)
++                      err = tree->ops->remove_extent(tree, ex, a, b);
++              if (err)
++                      goto out;
++
++              if (num == 0) {
++                      /* this extent is removed entirely mark slot unused */
++                      ex->ee_start = ex->ee_start_hi = 0;
++                      eh->eh_entries--;
++                      fu = ex;
++              }
++
++              ex->ee_block = block;
++              ex->ee_len = num;
++
++              err = ext3_ext_dirty(handle, tree, path + depth);
++              if (err)
++                      goto out;
++
++              ext_debug(tree, "new extent: %u:%u:%u\n",
++                        ex->ee_block, ex->ee_len, ex->ee_start);
++              ex--;
++      }
++
++      if (fu) {
++              /* reuse unused slots */
++              while (lu < le) {
++                      if (lu->ee_start) {
++                              *fu = *lu;
++                              lu->ee_start = lu->ee_start_hi = 0;
++                              fu++;
++                      }
++                      lu++;
++              }
++      }
++
++      if (correct_index && eh->eh_entries)
++              err = ext3_ext_correct_indexes(handle, tree, path);
++
++      /* if this leaf is free, then we should
++       * remove it from index block above */
++      if (err == 0 && eh->eh_entries == 0 && path[depth].p_bh != NULL)
++              err = ext3_ext_rm_idx(handle, tree, path + depth);
++
++out:
++      return err;
++}
++
++
++static struct ext3_extent_idx *
++ext3_ext_last_covered(struct ext3_extent_header *hdr, unsigned long block)
++{
++      struct ext3_extent_idx *ix;
++      
++      ix = EXT_LAST_INDEX(hdr);
++      while (ix != EXT_FIRST_INDEX(hdr)) {
++              if (ix->ei_block <= block)
++                      break;
++              ix--;
++      }
++      return ix;
++}
++
++/*
++ * returns 1 if current index have to be freed (even partial)
++ */
++static int inline
++ext3_ext_more_to_rm(struct ext3_ext_path *path)
++{
++      EXT_ASSERT(path->p_idx);
++
++      if (path->p_idx < EXT_FIRST_INDEX(path->p_hdr))
++              return 0;
++
++      /*
++       * if truncate on deeper level happened it it wasn't partial
++       * so we have to consider current index for truncation
++       */
++      if (path->p_hdr->eh_entries == path->p_block)
++              return 0;
++      return 1;
++}
++
++int ext3_ext_remove_space(struct ext3_extents_tree *tree,
++                        unsigned long start, unsigned long end)
++{
++      struct inode *inode = tree->inode;
++      struct super_block *sb = inode->i_sb;
++      int depth = EXT_DEPTH(tree);
++      struct ext3_ext_path *path;
++      handle_t *handle;
++      int i = 0, err = 0;
++
++      ext_debug(tree, "space to be removed: %lu:%lu\n", start, end);
++
++      /* probably first extent we're gonna free will be last in block */
++      handle = ext3_journal_start(inode, depth + 1);
++      if (IS_ERR(handle))
++              return PTR_ERR(handle);
++
++      ext3_ext_invalidate_cache(tree);
++
++      /*
++       * we start scanning from right side freeing all the blocks
++       * after i_size and walking into the deep
++       */
++      path = kmalloc(sizeof(struct ext3_ext_path) * (depth + 1), GFP_KERNEL);
++      if (IS_ERR(path)) {
++              ext3_error(sb, __FUNCTION__, "Can't allocate path array");
++              ext3_journal_stop(handle);
++              return -ENOMEM;
++      }
++      memset(path, 0, sizeof(struct ext3_ext_path) * (depth + 1));
++      path[i].p_hdr = EXT_ROOT_HDR(tree);
++      
++      while (i >= 0 && err == 0) {
++              if (i == depth) {
++                      /* this is leaf block */
++                      err = ext3_ext_rm_leaf(handle, tree, path, start, end);
++                      /* root level have p_bh == NULL, brelse() eats this */
++                      brelse(path[i].p_bh);
++                      i--;
++                      continue;
++              }
++              
++              /* this is index block */
++              if (!path[i].p_hdr) {
++                      ext_debug(tree, "initialize header\n");
++                      path[i].p_hdr = EXT_BLOCK_HDR(path[i].p_bh);
++              }
++
++              EXT_ASSERT(path[i].p_hdr->eh_entries <= path[i].p_hdr->eh_max);
++              EXT_ASSERT(path[i].p_hdr->eh_magic == EXT3_EXT_MAGIC);
++              
++              if (!path[i].p_idx) {
++                      /* this level hasn't touched yet */
++                      path[i].p_idx =
++                              ext3_ext_last_covered(path[i].p_hdr, end);
++                      path[i].p_block = path[i].p_hdr->eh_entries + 1;
++                      ext_debug(tree, "init index ptr: hdr 0x%p, num %d\n",
++                                path[i].p_hdr, path[i].p_hdr->eh_entries);
++              } else {
++                      /* we've already was here, see at next index */
++                      path[i].p_idx--;
++              }
++
++              ext_debug(tree, "level %d - index, first 0x%p, cur 0x%p\n",
++                        i, EXT_FIRST_INDEX(path[i].p_hdr),
++                        path[i].p_idx);
++              if (ext3_ext_more_to_rm(path + i)) {
++                      /* go to the next level */
++                      ext_debug(tree, "move to level %d (block %d)\n",
++                                i + 1, path[i].p_idx->ei_leaf);
++                      memset(path + i + 1, 0, sizeof(*path));
++                      path[i+1].p_bh = sb_bread(sb, path[i].p_idx->ei_leaf);
++                      if (!path[i+1].p_bh) {
++                              /* should we reset i_size? */
++                              err = -EIO;
++                              break;
++                      }
++                      /* put actual number of indexes to know is this
++                       * number got changed at the next iteration */
++                      path[i].p_block = path[i].p_hdr->eh_entries;
++                      i++;
++              } else {
++                      /* we finish processing this index, go up */
++                      if (path[i].p_hdr->eh_entries == 0 && i > 0) {
++                              /* index is empty, remove it
++                               * handle must be already prepared by the
++                               * truncatei_leaf() */
++                              err = ext3_ext_rm_idx(handle, tree, path + i);
++                      }
++                      /* root level have p_bh == NULL, brelse() eats this */
++                      brelse(path[i].p_bh);
++                      i--;
++                      ext_debug(tree, "return to level %d\n", i);
++              }
++      }
++
++      /* TODO: flexible tree reduction should be here */
++      if (path->p_hdr->eh_entries == 0) {
++              /*
++               * truncate to zero freed all the tree
++               * so, we need to correct eh_depth
++               */
++              err = ext3_ext_get_access(handle, tree, path);
++              if (err == 0) {
++                      EXT_ROOT_HDR(tree)->eh_depth = 0;
++                      EXT_ROOT_HDR(tree)->eh_max = ext3_ext_space_root(tree);
++                      err = ext3_ext_dirty(handle, tree, path);
++              }
++      }
++      ext3_ext_tree_changed(tree);
++
++      kfree(path);
++      ext3_journal_stop(handle);
++
++      return err;
++}
++
++int ext3_ext_calc_metadata_amount(struct ext3_extents_tree *tree, int blocks)
++{
++      int lcap, icap, rcap, leafs, idxs, num;
++
++      rcap = ext3_ext_space_root(tree);
++      if (blocks <= rcap) {
++              /* all extents fit to the root */
++              return 0;
++      }
++
++      rcap = ext3_ext_space_root_idx(tree);
++      lcap = ext3_ext_space_block(tree);
++      icap = ext3_ext_space_block_idx(tree);
++
++      num = leafs = (blocks + lcap - 1) / lcap;
++      if (leafs <= rcap) {
++              /* all pointers to leafs fit to the root */
++              return leafs;
++      }
++
++      /* ok. we need separate index block(s) to link all leaf blocks */
++      idxs = (leafs + icap - 1) / icap;
++      do {
++              num += idxs;
++              idxs = (idxs + icap - 1) / icap;
++      } while (idxs > rcap);
++
++      return num;
++}
++
++/*
++ * called at mount time
++ */
++void ext3_ext_init(struct super_block *sb)
++{
++      /*
++       * possible initialization would be here
++       */
++
++      if (test_opt(sb, EXTENTS)) {
++              printk("EXT3-fs: file extents enabled");
++#ifdef AGRESSIVE_TEST
++              printk(", agressive tests");
++#endif
++#ifdef CHECK_BINSEARCH
++              printk(", check binsearch");
++#endif
++              printk("\n");
++      }
++}
++
++/*
++ * called at umount time
++ */
++void ext3_ext_release(struct super_block *sb)
++{
++}
++
++/************************************************************************
++ * VFS related routines
++ ************************************************************************/
++
++static int ext3_get_inode_write_access(handle_t *handle, void *buffer)
++{
++      /* we use in-core data, not bh */
++      return 0;
++}
++
++static int ext3_mark_buffer_dirty(handle_t *handle, void *buffer)
++{
++      struct inode *inode = buffer;
++      return ext3_mark_inode_dirty(handle, inode);
++}
++
++static int ext3_ext_mergable(struct ext3_extent *ex1,
++                           struct ext3_extent *ex2)
++{
++      /* FIXME: support for large fs */
++      if (ex1->ee_start + ex1->ee_len == ex2->ee_start)
++              return 1;
++      return 0;
++}
++
++static int
++ext3_remove_blocks_credits(struct ext3_extents_tree *tree,
++                         struct ext3_extent *ex,
++                         unsigned long from, unsigned long to)
++{
++      int needed;
++      
++      /* at present, extent can't cross block group */;
++      needed = 4; /* bitmap + group desc + sb + inode */
++
++#ifdef CONFIG_QUOTA
++      needed += 2 * EXT3_SINGLEDATA_TRANS_BLOCKS;
++#endif
++      return needed;
++}
++
++static int
++ext3_remove_blocks(struct ext3_extents_tree *tree,
++                 struct ext3_extent *ex,
++                 unsigned long from, unsigned long to)
++{
++      int needed = ext3_remove_blocks_credits(tree, ex, from, to);
++      handle_t *handle = ext3_journal_start(tree->inode, needed);
++      struct buffer_head *bh;
++      int i;
++
++      if (IS_ERR(handle))
++              return PTR_ERR(handle);
++      if (from >= ex->ee_block && to == ex->ee_block + ex->ee_len - 1) {
++              /* tail removal */
++              unsigned long num, start;
++              num = ex->ee_block + ex->ee_len - from;
++              start = ex->ee_start + ex->ee_len - num;
++              ext_debug(tree, "free last %lu blocks starting %lu\n",
++                        num, start);
++              for (i = 0; i < num; i++) {
++                      bh = sb_find_get_block(tree->inode->i_sb, start + i);
++                      ext3_forget(handle, 0, tree->inode, bh, start + i);
++              }
++              ext3_free_blocks(handle, tree->inode, start, num);
++      } else if (from == ex->ee_block && to <= ex->ee_block + ex->ee_len - 1) {
++              printk("strange request: removal %lu-%lu from %u:%u\n",
++                     from, to, ex->ee_block, ex->ee_len);
++      } else {
++              printk("strange request: removal(2) %lu-%lu from %u:%u\n",
++                     from, to, ex->ee_block, ex->ee_len);
++      }
++      ext3_journal_stop(handle);
++      return 0;
++}
++
++static int ext3_ext_find_goal(struct inode *inode,
++                            struct ext3_ext_path *path, unsigned long block)
++{
++      struct ext3_inode_info *ei = EXT3_I(inode);
++      unsigned long bg_start;
++      unsigned long colour;
++      int depth;
++      
++      if (path) {
++              struct ext3_extent *ex;
++              depth = path->p_depth;
++              
++              /* try to predict block placement */
++              if ((ex = path[depth].p_ext))
++                      return ex->ee_start + (block - ex->ee_block);
++
++              /* it looks index is empty
++               * try to find starting from index itself */
++              if (path[depth].p_bh)
++                      return path[depth].p_bh->b_blocknr;
++      }
++
++      /* OK. use inode's group */
++      bg_start = (ei->i_block_group * EXT3_BLOCKS_PER_GROUP(inode->i_sb)) +
++              le32_to_cpu(EXT3_SB(inode->i_sb)->s_es->s_first_data_block);
++      colour = (current->pid % 16) *
++                      (EXT3_BLOCKS_PER_GROUP(inode->i_sb) / 16);
++      return bg_start + colour + block;
++}
++
++static int ext3_new_block_cb(handle_t *handle, struct ext3_extents_tree *tree,
++                           struct ext3_ext_path *path,
++                           struct ext3_extent *ex, int *err)
++{
++      struct inode *inode = tree->inode;
++      int newblock, goal;
++      
++      EXT_ASSERT(path);
++      EXT_ASSERT(ex);
++      EXT_ASSERT(ex->ee_start);
++      EXT_ASSERT(ex->ee_len);
++      
++      /* reuse block from the extent to order data/metadata */
++      newblock = ex->ee_start++;
++      ex->ee_len--;
++      if (ex->ee_len == 0) {
++              ex->ee_len = 1;
++              /* allocate new block for the extent */
++              goal = ext3_ext_find_goal(inode, path, ex->ee_block);
++              ex->ee_start = ext3_new_block(handle, inode, goal, err);
++              ex->ee_start_hi = 0;
++              if (ex->ee_start == 0) {
++                      /* error occured: restore old extent */
++                      ex->ee_start = newblock;
++                      return 0;
++              }
++      }
++      return newblock;
++}
++
++static struct ext3_extents_helpers ext3_blockmap_helpers = {
++      .get_write_access       = ext3_get_inode_write_access,
++      .mark_buffer_dirty      = ext3_mark_buffer_dirty,
++      .mergable               = ext3_ext_mergable,
++      .new_block              = ext3_new_block_cb,
++      .remove_extent          = ext3_remove_blocks,
++      .remove_extent_credits  = ext3_remove_blocks_credits,
++};
++
++void ext3_init_tree_desc(struct ext3_extents_tree *tree,
++                       struct inode *inode)
++{
++      tree->inode = inode;
++      tree->root = (void *) EXT3_I(inode)->i_data;
++      tree->buffer = (void *) inode;
++      tree->buffer_len = sizeof(EXT3_I(inode)->i_data);
++      tree->cex = (struct ext3_ext_cache *) &EXT3_I(inode)->i_cached_extent;
++      tree->ops = &ext3_blockmap_helpers;
++}
++
++int ext3_ext_get_block(handle_t *handle, struct inode *inode,
++                     long iblock, struct buffer_head *bh_result,
++                     int create, int extend_disksize)
++{
++      struct ext3_ext_path *path = NULL;
++      struct ext3_extent newex;
++      struct ext3_extent *ex;
++      int goal, newblock, err = 0, depth;
++      struct ext3_extents_tree tree;
++
++      clear_buffer_new(bh_result);
++      ext3_init_tree_desc(&tree, inode);
++      ext_debug(&tree, "block %d requested for inode %u\n",
++                (int) iblock, (unsigned) inode->i_ino);
++      down(&EXT3_I(inode)->truncate_sem);
++
++      /* check in cache */
++      if ((goal = ext3_ext_in_cache(&tree, iblock, &newex))) {
++              if (goal == EXT3_EXT_CACHE_GAP) {
++                      if (!create) {
++                              /* block isn't allocated yet and
++                               * user don't want to allocate it */
++                              goto out2;
++                      }
++                      /* we should allocate requested block */
++              } else if (goal == EXT3_EXT_CACHE_EXTENT) {
++                      /* block is already allocated */
++                      newblock = iblock - newex.ee_block + newex.ee_start;
++                      goto out;
++              } else {
++                      EXT_ASSERT(0);
++              }
++      }
++
++      /* find extent for this block */
++      path = ext3_ext_find_extent(&tree, iblock, NULL);
++      if (IS_ERR(path)) {
++              err = PTR_ERR(path);
++              path = NULL;
++              goto out2;
++      }
++
++      depth = EXT_DEPTH(&tree);
++
++      /*
++       * consistent leaf must not be empty
++       * this situations is possible, though, _during_ tree modification
++       * this is why assert can't be put in ext3_ext_find_extent()
++       */
++      EXT_ASSERT(path[depth].p_ext != NULL || depth == 0);
++
++      if ((ex = path[depth].p_ext)) {
++              /* if found exent covers block, simple return it */
++              if (iblock >= ex->ee_block && iblock < ex->ee_block + ex->ee_len) {
++                      newblock = iblock - ex->ee_block + ex->ee_start;
++                      ext_debug(&tree, "%d fit into %d:%d -> %d\n",
++                                (int) iblock, ex->ee_block, ex->ee_len,
++                                newblock);
++                      ext3_ext_put_in_cache(&tree, ex->ee_block,
++                                            ex->ee_len, ex->ee_start,
++                                            EXT3_EXT_CACHE_EXTENT);
++                      goto out;
++              }
++      }
++
++      /*
++       * requested block isn't allocated yet
++       * we couldn't try to create block if create flag is zero 
++       */
++      if (!create) {
++              /* put just found gap into cache to speedup subsequest reqs */
++              ext3_ext_put_gap_in_cache(&tree, path, iblock);
++              goto out2;
++      }
++
++      /* allocate new block */
++      goal = ext3_ext_find_goal(inode, path, iblock);
++      newblock = ext3_new_block(handle, inode, goal, &err);
++      if (!newblock)
++              goto out2;
++      ext_debug(&tree, "allocate new block: goal %d, found %d\n",
++                goal, newblock);
++
++      /* try to insert new extent into found leaf and return */
++      newex.ee_block = iblock;
++      newex.ee_start = newblock;
++      newex.ee_start_hi = 0;
++      newex.ee_len = 1;
++      err = ext3_ext_insert_extent(handle, &tree, path, &newex);
++      if (err)
++              goto out2;
++      
++      if (extend_disksize && inode->i_size > EXT3_I(inode)->i_disksize)
++              EXT3_I(inode)->i_disksize = inode->i_size;
++
++      /* previous routine could use block we allocated */
++      newblock = newex.ee_start;
++      set_buffer_new(bh_result);
++
++      ext3_ext_put_in_cache(&tree, newex.ee_block, newex.ee_len,
++                            newex.ee_start, EXT3_EXT_CACHE_EXTENT);
++out:
++      ext3_ext_show_leaf(&tree, path);
++      map_bh(bh_result, inode->i_sb, newblock);
++out2:
++      if (path) {
++              ext3_ext_drop_refs(path);
++              kfree(path);
++      }
++      up(&EXT3_I(inode)->truncate_sem);
++
++      return err;     
++}
++
++void ext3_ext_truncate(struct inode * inode, struct page *page)
++{
++      struct address_space *mapping = inode->i_mapping;
++      struct super_block *sb = inode->i_sb;
++      struct ext3_extents_tree tree;
++      unsigned long last_block;
++      handle_t *handle;
++      int err = 0;
++
++      ext3_init_tree_desc(&tree, inode);
++
++      /*
++       * probably first extent we're gonna free will be last in block
++       */
++      err = ext3_writepage_trans_blocks(inode) + 3;
++      handle = ext3_journal_start(inode, err);
++      if (IS_ERR(handle)) {
++              if (page) {
++                      clear_highpage(page);
++                      flush_dcache_page(page);
++                      unlock_page(page);
++                      page_cache_release(page);
++              }
++              return;
++      }
++
++      if (page)
++              ext3_block_truncate_page(handle, page, mapping, inode->i_size);
++
++      down(&EXT3_I(inode)->truncate_sem);
++      ext3_ext_invalidate_cache(&tree);
++
++      /* 
++       * TODO: optimization is possible here
++       * probably we need not scaning at all,
++       * because page truncation is enough
++       */
++      if (ext3_orphan_add(handle, inode))
++              goto out_stop;
++
++      /* we have to know where to truncate from in crash case */
++      EXT3_I(inode)->i_disksize = inode->i_size;
++      ext3_mark_inode_dirty(handle, inode);
++
++      last_block = (inode->i_size + sb->s_blocksize - 1) >>
++                      EXT3_BLOCK_SIZE_BITS(sb);
++      err = ext3_ext_remove_space(&tree, last_block, EXT_MAX_BLOCK);
++      
++      /* In a multi-transaction truncate, we only make the final
++       * transaction synchronous */
++      if (IS_SYNC(inode))
++              handle->h_sync = 1;
++
++out_stop:
++      /*
++       * If this was a simple ftruncate(), and the file will remain alive
++       * then we need to clear up the orphan record which we created above.
++       * However, if this was a real unlink then we were called by
++       * ext3_delete_inode(), and we allow that function to clean up the
++       * orphan info for us.
++       */
++      if (inode->i_nlink)
++              ext3_orphan_del(handle, inode);
++
++      up(&EXT3_I(inode)->truncate_sem);
++      ext3_journal_stop(handle);
++}
++
++/*
++ * this routine calculate max number of blocks we could modify
++ * in order to allocate new block for an inode
++ */
++int ext3_ext_writepage_trans_blocks(struct inode *inode, int num)
++{
++      struct ext3_extents_tree tree;
++      int needed;
++      
++      ext3_init_tree_desc(&tree, inode);
++      
++      needed = ext3_ext_calc_credits_for_insert(&tree, NULL);
++
++      /* caller want to allocate num blocks */
++      needed *= num;
++      
++#ifdef CONFIG_QUOTA
++      /* 
++       * FIXME: real calculation should be here
++       * it depends on blockmap format of qouta file
++       */
++      needed += 2 * EXT3_SINGLEDATA_TRANS_BLOCKS;
++#endif
++
++      return needed;
++}
++
++void ext3_extents_initialize_blockmap(handle_t *handle, struct inode *inode)
++{
++      struct ext3_extents_tree tree;
++
++      ext3_init_tree_desc(&tree, inode);
++      ext3_extent_tree_init(handle, &tree);
++}
++
++int ext3_ext_calc_blockmap_metadata(struct inode *inode, int blocks)
++{
++      struct ext3_extents_tree tree;
++
++      ext3_init_tree_desc(&tree, inode);
++      return ext3_ext_calc_metadata_amount(&tree, blocks);
++}
++      
++static int
++ext3_ext_store_extent_cb(struct ext3_extents_tree *tree,
++                       struct ext3_ext_path *path,
++                       struct ext3_ext_cache *newex)
++{
++      struct ext3_extent_buf *buf = (struct ext3_extent_buf *) tree->private;
++
++      if (newex->ec_type != EXT3_EXT_CACHE_EXTENT)
++              return EXT_CONTINUE;
++
++      if (buf->err < 0)
++              return EXT_BREAK;
++      if (buf->cur - buf->buffer + sizeof(*newex) > buf->buflen)
++              return EXT_BREAK;
++
++      if (!copy_to_user(buf->cur, newex, sizeof(*newex))) {
++              buf->err++;
++              buf->cur += sizeof(*newex);
++      } else {
++              buf->err = -EFAULT;
++              return EXT_BREAK;
++      }
++      return EXT_CONTINUE;
++}
++
++static int
++ext3_ext_collect_stats_cb(struct ext3_extents_tree *tree,
++                        struct ext3_ext_path *path,
++                        struct ext3_ext_cache *ex)
++{
++      struct ext3_extent_tree_stats *buf =
++              (struct ext3_extent_tree_stats *) tree->private;
++      int depth;
++
++      if (ex->ec_type != EXT3_EXT_CACHE_EXTENT)
++              return EXT_CONTINUE;
++
++      depth = EXT_DEPTH(tree);
++      buf->extents_num++;
++      if (path[depth].p_ext == EXT_FIRST_EXTENT(path[depth].p_hdr))
++              buf->leaf_num++;
++      return EXT_CONTINUE;
++}
++
++int ext3_ext_ioctl(struct inode *inode, struct file *filp, unsigned int cmd,
++                 unsigned long arg)
++{
++      int err = 0;
++
++      if (!(EXT3_I(inode)->i_flags & EXT3_EXTENTS_FL))
++              return -EINVAL;
++
++      if (cmd == EXT3_IOC_GET_EXTENTS) {
++              struct ext3_extent_buf buf;
++              struct ext3_extents_tree tree;
++
++              if (copy_from_user(&buf, (void *) arg, sizeof(buf)))
++                      return -EFAULT;
++
++              ext3_init_tree_desc(&tree, inode);
++              buf.cur = buf.buffer;
++              buf.err = 0;
++              tree.private = &buf;
++              down(&EXT3_I(inode)->truncate_sem);
++              err = ext3_ext_walk_space(&tree, buf.start, EXT_MAX_BLOCK,
++                                        ext3_ext_store_extent_cb);
++              up(&EXT3_I(inode)->truncate_sem);
++              if (err == 0)
++                      err = buf.err;
++      } else if (cmd == EXT3_IOC_GET_TREE_STATS) {
++              struct ext3_extent_tree_stats buf;
++              struct ext3_extents_tree tree;
++
++              ext3_init_tree_desc(&tree, inode);
++              down(&EXT3_I(inode)->truncate_sem);
++              buf.depth = EXT_DEPTH(&tree);
++              buf.extents_num = 0;
++              buf.leaf_num = 0;
++              tree.private = &buf;
++              err = ext3_ext_walk_space(&tree, 0, EXT_MAX_BLOCK,
++                                        ext3_ext_collect_stats_cb);
++              up(&EXT3_I(inode)->truncate_sem);
++              if (!err)
++                      err = copy_to_user((void *) arg, &buf, sizeof(buf));
++      } else if (cmd == EXT3_IOC_GET_TREE_DEPTH) {
++              struct ext3_extents_tree tree;
++              ext3_init_tree_desc(&tree, inode);
++              down(&EXT3_I(inode)->truncate_sem);
++              err = EXT_DEPTH(&tree);
++              up(&EXT3_I(inode)->truncate_sem);
++      }
++
++      return err;
++}
++
++EXPORT_SYMBOL(ext3_init_tree_desc);
++EXPORT_SYMBOL(ext3_mark_inode_dirty);
++EXPORT_SYMBOL(ext3_ext_invalidate_cache);
++EXPORT_SYMBOL(ext3_ext_insert_extent);
++EXPORT_SYMBOL(ext3_ext_walk_space);
++EXPORT_SYMBOL(ext3_ext_find_goal);
++EXPORT_SYMBOL(ext3_ext_calc_credits_for_insert);
+Index: linux-2.6.16.27-0.9/fs/ext3/ialloc.c
+===================================================================
+--- linux-2.6.16.27-0.9.orig/fs/ext3/ialloc.c
++++ linux-2.6.16.27-0.9/fs/ext3/ialloc.c
+@@ -601,7 +601,7 @@ got:
+       ei->i_dir_start_lookup = 0;
+       ei->i_disksize = 0;
+-      ei->i_flags = EXT3_I(dir)->i_flags & ~EXT3_INDEX_FL;
++      ei->i_flags = EXT3_I(dir)->i_flags & ~(EXT3_INDEX_FL|EXT3_EXTENTS_FL);
+       if (S_ISLNK(mode))
+               ei->i_flags &= ~(EXT3_IMMUTABLE_FL|EXT3_APPEND_FL);
+       /* dirsync only applies to directories */
+@@ -645,6 +645,18 @@ got:
+       if (err)
+               goto fail_free_drop;
++      if (test_opt(sb, EXTENTS) && S_ISREG(inode->i_mode)) {
++              EXT3_I(inode)->i_flags |= EXT3_EXTENTS_FL;
++              ext3_extents_initialize_blockmap(handle, inode);
++              if (!EXT3_HAS_INCOMPAT_FEATURE(sb, EXT3_FEATURE_INCOMPAT_EXTENTS)) {
++                      err = ext3_journal_get_write_access(handle, EXT3_SB(sb)->s_sbh);
++                      if (err) goto fail;
++                      EXT3_SET_INCOMPAT_FEATURE(sb, EXT3_FEATURE_INCOMPAT_EXTENTS);
++                      BUFFER_TRACE(EXT3_SB(sb)->s_sbh, "call ext3_journal_dirty_metadata");
++                      err = ext3_journal_dirty_metadata(handle, EXT3_SB(sb)->s_sbh);
++              }
++      }
++
+       err = ext3_mark_inode_dirty(handle, inode);
+       if (err) {
+               ext3_std_error(sb, err);
+Index: linux-2.6.16.27-0.9/fs/ext3/inode.c
+===================================================================
+--- linux-2.6.16.27-0.9.orig/fs/ext3/inode.c
++++ linux-2.6.16.27-0.9/fs/ext3/inode.c
+@@ -40,7 +40,7 @@
+ #include "iopen.h"
+ #include "acl.h"
+-static int ext3_writepage_trans_blocks(struct inode *inode);
++int ext3_writepage_trans_blocks(struct inode *inode);
+ /*
+  * Test whether an inode is a fast symlink.
+@@ -788,6 +788,17 @@ out:
+       return err;
+ }
++static inline int
++ext3_get_block_wrap(handle_t *handle, struct inode *inode, long block,
++                  struct buffer_head *bh, int create, int extend_disksize)
++{
++      if (EXT3_I(inode)->i_flags & EXT3_EXTENTS_FL)
++              return ext3_ext_get_block(handle, inode, block, bh, create,
++                                        extend_disksize);
++      return ext3_get_block_handle(handle, inode, block, bh, create,
++                                   extend_disksize);
++}
++
+ static int ext3_get_block(struct inode *inode, sector_t iblock,
+                       struct buffer_head *bh_result, int create)
+ {
+@@ -798,8 +809,8 @@ static int ext3_get_block(struct inode *
+               handle = ext3_journal_current_handle();
+               J_ASSERT(handle != 0);
+       }
+-      ret = ext3_get_block_handle(handle, inode, iblock,
+-                              bh_result, create, 1);
++      ret = ext3_get_block_wrap(handle, inode, iblock,
++                                bh_result, create, 1);
+       return ret;
+ }
+@@ -843,7 +854,7 @@ ext3_direct_io_get_blocks(struct inode *
+ get_block:
+       if (ret == 0)
+-              ret = ext3_get_block_handle(handle, inode, iblock,
++              ret = ext3_get_block_wrap(handle, inode, iblock,
+                                       bh_result, create, 0);
+       bh_result->b_size = (1 << inode->i_blkbits);
+       return ret;
+@@ -863,7 +874,7 @@ struct buffer_head *ext3_getblk(handle_t
+       dummy.b_state = 0;
+       dummy.b_blocknr = -1000;
+       buffer_trace_init(&dummy.b_history);
+-      *errp = ext3_get_block_handle(handle, inode, block, &dummy, create, 1);
++      *errp = ext3_get_block_wrap(handle, inode, block, &dummy, create, 1);
+       if (!*errp && buffer_mapped(&dummy)) {
+               struct buffer_head *bh;
+               bh = sb_getblk(inode->i_sb, dummy.b_blocknr);
+@@ -1606,7 +1617,7 @@ void ext3_set_aops(struct inode *inode)
+  * This required during truncate. We need to physically zero the tail end
+  * of that block so it doesn't yield old data if the file is later grown.
+  */
+-static int ext3_block_truncate_page(handle_t *handle, struct page *page,
++int ext3_block_truncate_page(handle_t *handle, struct page *page,
+               struct address_space *mapping, loff_t from)
+ {
+       unsigned long index = from >> PAGE_CACHE_SHIFT;
+@@ -2116,6 +2127,9 @@ void ext3_truncate(struct inode * inode)
+                       return;
+       }
++      if (EXT3_I(inode)->i_flags & EXT3_EXTENTS_FL)
++              return ext3_ext_truncate(inode, page);
++
+       handle = start_transaction(inode);
+       if (IS_ERR(handle)) {
+               if (page) {
+@@ -2863,12 +2877,15 @@ err_out:
+  * block and work out the exact number of indirects which are touched.  Pah.
+  */
+-static int ext3_writepage_trans_blocks(struct inode *inode)
++int ext3_writepage_trans_blocks(struct inode *inode)
+ {
+       int bpp = ext3_journal_blocks_per_page(inode);
+       int indirects = (EXT3_NDIR_BLOCKS % bpp) ? 5 : 3;
+       int ret;
++      if (EXT3_I(inode)->i_flags & EXT3_EXTENTS_FL)
++              return ext3_ext_writepage_trans_blocks(inode, bpp);
++
+       if (ext3_should_journal_data(inode))
+               ret = 3 * (bpp + indirects) + 2;
+       else
+Index: linux-2.6.16.27-0.9/fs/ext3/Makefile
+===================================================================
+--- linux-2.6.16.27-0.9.orig/fs/ext3/Makefile
++++ linux-2.6.16.27-0.9/fs/ext3/Makefile
+@@ -5,7 +5,8 @@
+ obj-$(CONFIG_EXT3_FS) += ext3.o
+ ext3-y        := balloc.o bitmap.o dir.o file.o fsync.o ialloc.o inode.o iopen.o \
+-         ioctl.o namei.o super.o symlink.o hash.o resize.o
++         ioctl.o namei.o super.o symlink.o hash.o resize.o \
++         extents.o
+ ext3-$(CONFIG_EXT3_FS_XATTR)   += xattr.o xattr_user.o xattr_trusted.o
+ ext3-$(CONFIG_EXT3_FS_POSIX_ACL) += acl.o
+Index: linux-2.6.16.27-0.9/fs/ext3/super.c
+===================================================================
+--- linux-2.6.16.27-0.9.orig/fs/ext3/super.c
++++ linux-2.6.16.27-0.9/fs/ext3/super.c
+@@ -392,6 +392,7 @@ static void ext3_put_super (struct super
+       struct ext3_super_block *es = sbi->s_es;
+       int i;
++      ext3_ext_release(sb);
+       ext3_xattr_put_super(sb);
+       journal_destroy(sbi->s_journal);
+       if (!(sb->s_flags & MS_RDONLY)) {
+@@ -456,6 +457,8 @@ static struct inode *ext3_alloc_inode(st
+ #endif
+       ei->i_block_alloc_info = NULL;
+       ei->vfs_inode.i_version = 1;
++      
++      memset(&ei->i_cached_extent, 0, sizeof(ei->i_cached_extent));
+       return &ei->vfs_inode;
+ }
+@@ -681,6 +684,7 @@ enum {
+       Opt_jqfmt_vfsold, Opt_jqfmt_vfsv0, Opt_quota, Opt_noquota,
+       Opt_ignore, Opt_barrier, Opt_err, Opt_resize, Opt_usrquota,
+       Opt_iopen, Opt_noiopen, Opt_iopen_nopriv,
++      Opt_extents, Opt_noextents, Opt_extdebug,
+       Opt_grpquota
+ };
+@@ -732,6 +736,9 @@ static match_table_t tokens = {
+       {Opt_iopen, "iopen"},
+       {Opt_noiopen, "noiopen"},
+       {Opt_iopen_nopriv, "iopen_nopriv"},
++      {Opt_extents, "extents"},
++      {Opt_noextents, "noextents"},
++      {Opt_extdebug, "extdebug"},
+       {Opt_barrier, "barrier=%u"},
+       {Opt_err, NULL},
+       {Opt_resize, "resize"},
+@@ -1073,6 +1080,15 @@ clear_qf_name:
+               case Opt_nobh:
+                       set_opt(sbi->s_mount_opt, NOBH);
+                       break;
++              case Opt_extents:
++                      set_opt (sbi->s_mount_opt, EXTENTS);
++                      break;
++              case Opt_noextents:
++                      clear_opt (sbi->s_mount_opt, EXTENTS);
++                      break;
++              case Opt_extdebug:
++                      set_opt (sbi->s_mount_opt, EXTDEBUG);
++                      break;
+               default:
+                       printk (KERN_ERR
+                               "EXT3-fs: Unrecognized mount option \"%s\" "
+@@ -1799,6 +1815,7 @@ static int ext3_fill_super (struct super
+       percpu_counter_mod(&sbi->s_dirs_counter,
+               ext3_count_dirs(sb));
++      ext3_ext_init(sb);
+       lock_kernel();
+       return 0;
+Index: linux-2.6.16.27-0.9/fs/ext3/ioctl.c
+===================================================================
+--- linux-2.6.16.27-0.9.orig/fs/ext3/ioctl.c
++++ linux-2.6.16.27-0.9/fs/ext3/ioctl.c
+@@ -125,6 +125,10 @@ flags_err:
+                       err = ext3_change_inode_journal_flag(inode, jflag);
+               return err;
+       }
++      case EXT3_IOC_GET_EXTENTS:
++      case EXT3_IOC_GET_TREE_STATS:
++      case EXT3_IOC_GET_TREE_DEPTH:
++              return ext3_ext_ioctl(inode, filp, cmd, arg);
+       case EXT3_IOC_GETVERSION:
+       case EXT3_IOC_GETVERSION_OLD:
+               return put_user(inode->i_generation, (int __user *) arg);
+Index: linux-2.6.16.27-0.9/include/linux/ext3_fs.h
+===================================================================
+--- linux-2.6.16.27-0.9.orig/include/linux/ext3_fs.h
++++ linux-2.6.16.27-0.9/include/linux/ext3_fs.h
+@@ -185,9 +185,10 @@ struct ext3_group_desc
+ #define EXT3_NOTAIL_FL                        0x00008000 /* file tail should not be merged */
+ #define EXT3_DIRSYNC_FL                       0x00010000 /* dirsync behaviour (directories only) */
+ #define EXT3_TOPDIR_FL                        0x00020000 /* Top of directory hierarchies*/
++#define EXT3_EXTENTS_FL                       0x00080000 /* Inode uses extents */
+ #define EXT3_RESERVED_FL              0x80000000 /* reserved for ext3 lib */
+-#define EXT3_FL_USER_VISIBLE          0x0003DFFF /* User visible flags */
++#define EXT3_FL_USER_VISIBLE          0x000BDFFF /* User visible flags */
+ #define EXT3_FL_USER_MODIFIABLE               0x000380FF /* User modifiable flags */
+ /*
+@@ -237,6 +238,9 @@ struct ext3_new_group_data {
+ #endif
+ #define EXT3_IOC_GETRSVSZ             _IOR('f', 5, long)
+ #define EXT3_IOC_SETRSVSZ             _IOW('f', 6, long)
++#define EXT3_IOC_GET_EXTENTS          _IOR('f', 7, long)
++#define EXT3_IOC_GET_TREE_DEPTH               _IOR('f', 8, long)
++#define EXT3_IOC_GET_TREE_STATS               _IOR('f', 9, long)
+ /*
+  *  Mount options
+@@ -377,6 +381,8 @@ struct ext3_inode {
+ #define EXT3_MOUNT_GRPQUOTA           0x200000 /* "old" group quota */
+ #define EXT3_MOUNT_IOPEN              0x400000        /* Allow access via iopen */
+ #define EXT3_MOUNT_IOPEN_NOPRIV               0x800000/* Make iopen world-readable */
++#define EXT3_MOUNT_EXTENTS            0x1000000/* Extents support */
++#define EXT3_MOUNT_EXTDEBUG           0x2000000/* Extents debug */
+ /* Compatibility, for having both ext2_fs.h and ext3_fs.h included at once */
+ #ifndef clear_opt
+@@ -565,11 +571,13 @@ static inline struct ext3_inode_info *EX
+ #define EXT3_FEATURE_INCOMPAT_RECOVER         0x0004 /* Needs recovery */
+ #define EXT3_FEATURE_INCOMPAT_JOURNAL_DEV     0x0008 /* Journal device */
+ #define EXT3_FEATURE_INCOMPAT_META_BG         0x0010
++#define EXT3_FEATURE_INCOMPAT_EXTENTS         0x0040 /* extents support */
+ #define EXT3_FEATURE_COMPAT_SUPP      EXT2_FEATURE_COMPAT_EXT_ATTR
+ #define EXT3_FEATURE_INCOMPAT_SUPP    (EXT3_FEATURE_INCOMPAT_FILETYPE| \
+                                        EXT3_FEATURE_INCOMPAT_RECOVER| \
+-                                       EXT3_FEATURE_INCOMPAT_META_BG)
++                                       EXT3_FEATURE_INCOMPAT_META_BG| \
++                                       EXT3_FEATURE_INCOMPAT_EXTENTS)
+ #define EXT3_FEATURE_RO_COMPAT_SUPP   (EXT3_FEATURE_RO_COMPAT_SPARSE_SUPER| \
+                                        EXT3_FEATURE_RO_COMPAT_LARGE_FILE| \
+                                        EXT3_FEATURE_RO_COMPAT_BTREE_DIR)
+@@ -776,6 +784,7 @@ extern unsigned long ext3_count_free (st
+ /* inode.c */
++extern int ext3_block_truncate_page(handle_t *, struct page *, struct address_space *, loff_t);
+ int ext3_forget(handle_t *, int, struct inode *, struct buffer_head *, int);
+ struct buffer_head * ext3_getblk (handle_t *, struct inode *, long, int, int *);
+ struct buffer_head * ext3_bread (handle_t *, struct inode *, int, int, int *);
+@@ -795,6 +804,7 @@ extern int ext3_get_inode_loc(struct ino
+ extern void ext3_truncate (struct inode *);
+ extern void ext3_set_inode_flags(struct inode *);
+ extern void ext3_set_aops(struct inode *inode);
++extern int ext3_writepage_trans_blocks(struct inode *inode);
+ /* ioctl.c */
+ extern int ext3_ioctl (struct inode *, struct file *, unsigned int,
+@@ -848,6 +858,16 @@ extern struct inode_operations ext3_spec
+ extern struct inode_operations ext3_symlink_inode_operations;
+ extern struct inode_operations ext3_fast_symlink_inode_operations;
++/* extents.c */
++extern int ext3_ext_writepage_trans_blocks(struct inode *, int);
++extern int ext3_ext_get_block(handle_t *, struct inode *, long,
++                            struct buffer_head *, int, int);
++extern void ext3_ext_truncate(struct inode *, struct page *);
++extern void ext3_ext_init(struct super_block *);
++extern void ext3_ext_release(struct super_block *);
++extern void ext3_extents_initialize_blockmap(handle_t *, struct inode *);
++extern int ext3_ext_ioctl(struct inode *inode, struct file *filp,
++                        unsigned int cmd, unsigned long arg);
+ #endif        /* __KERNEL__ */
+Index: linux-2.6.16.27-0.9/include/linux/ext3_extents.h
+===================================================================
+--- /dev/null
++++ linux-2.6.16.27-0.9/include/linux/ext3_extents.h
+@@ -0,0 +1,262 @@
++/*
++ * Copyright (c) 2003, Cluster File Systems, Inc, info@clusterfs.com
++ * Written by Alex Tomas <alex@clusterfs.com>
++ *
++ * This program is free software; you can redistribute it and/or modify
++ * it under the terms of the GNU General Public License version 2 as
++ * published by the Free Software Foundation.
++ *
++ * This program is distributed in the hope that it will be useful,
++ * but WITHOUT ANY WARRANTY; without even the implied warranty of
++ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
++ * GNU General Public License for more details.
++ *
++ * You should have received a copy of the GNU General Public Licens
++ * along with this program; if not, write to the Free Software
++ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-
++ */
++
++#ifndef _LINUX_EXT3_EXTENTS
++#define _LINUX_EXT3_EXTENTS
++
++/*
++ * with AGRESSIVE_TEST defined capacity of index/leaf blocks
++ * become very little, so index split, in-depth growing and
++ * other hard changes happens much more often
++ * this is for debug purposes only
++ */
++#define AGRESSIVE_TEST_
++
++/*
++ * if CHECK_BINSEARCH defined, then results of binary search
++ * will be checked by linear search
++ */
++#define CHECK_BINSEARCH_
++
++/*
++ * if EXT_DEBUG is defined you can use 'extdebug' mount option
++ * to get lots of info what's going on
++ */
++#define EXT_DEBUG_
++#ifdef EXT_DEBUG
++#define ext_debug(tree,fmt,a...)                      \
++do {                                                  \
++      if (test_opt((tree)->inode->i_sb, EXTDEBUG))    \
++              printk(fmt, ##a);                       \
++} while (0);
++#else
++#define ext_debug(tree,fmt,a...)
++#endif
++
++/*
++ * if EXT_STATS is defined then stats numbers are collected
++ * these number will be displayed at umount time
++ */
++#define EXT_STATS_
++
++
++#define EXT3_ALLOC_NEEDED     3       /* block bitmap + group desc. + sb */
++
++/*
++ * ext3_inode has i_block array (total 60 bytes)
++ * first 4 bytes are used to store:
++ *  - tree depth (0 mean there is no tree yet. all extents in the inode)
++ *  - number of alive extents in the inode
++ */
++
++/*
++ * this is extent on-disk structure
++ * it's used at the bottom of the tree
++ */
++struct ext3_extent {
++      __u32   ee_block;       /* first logical block extent covers */
++      __u16   ee_len;         /* number of blocks covered by extent */
++      __u16   ee_start_hi;    /* high 16 bits of physical block */
++      __u32   ee_start;       /* low 32 bigs of physical block */
++};
++
++/*
++ * this is index on-disk structure
++ * it's used at all the levels, but the bottom
++ */
++struct ext3_extent_idx {
++      __u32   ei_block;       /* index covers logical blocks from 'block' */
++      __u32   ei_leaf;        /* pointer to the physical block of the next *
++                               * level. leaf or next index could bet here */
++      __u16   ei_leaf_hi;     /* high 16 bits of physical block */
++      __u16   ei_unused;
++};
++
++/*
++ * each block (leaves and indexes), even inode-stored has header
++ */
++struct ext3_extent_header {   
++      __u16   eh_magic;       /* probably will support different formats */   
++      __u16   eh_entries;     /* number of valid entries */
++      __u16   eh_max;         /* capacity of store in entries */
++      __u16   eh_depth;       /* has tree real underlaying blocks? */
++      __u32   eh_generation;  /* flags(8 bits) | generation of the tree */
++};
++
++#define EXT3_EXT_MAGIC                0xf30a
++
++/*
++ * array of ext3_ext_path contains path to some extent
++ * creation/lookup routines use it for traversal/splitting/etc
++ * truncate uses it to simulate recursive walking
++ */
++struct ext3_ext_path {
++      __u32                           p_block;
++      __u16                           p_depth;
++      struct ext3_extent              *p_ext;
++      struct ext3_extent_idx          *p_idx;
++      struct ext3_extent_header       *p_hdr;
++      struct buffer_head              *p_bh;
++};
++
++/*
++ * structure for external API
++ */
++
++/*
++ * storage for cached extent
++ */
++struct ext3_ext_cache {
++      __u32   ec_start;
++      __u32   ec_block;
++      __u32   ec_len;
++      __u32   ec_type;
++};
++
++#define EXT3_EXT_CACHE_NO     0
++#define EXT3_EXT_CACHE_GAP    1
++#define EXT3_EXT_CACHE_EXTENT 2
++
++/*
++ * ext3_extents_tree is used to pass initial information
++ * to top-level extents API
++ */
++struct ext3_extents_helpers;
++struct ext3_extents_tree {
++      struct inode *inode;    /* inode which tree belongs to */
++      void *root;             /* ptr to data top of tree resides at */
++      void *buffer;           /* will be passed as arg to ^^ routines */
++      int buffer_len;
++      void *private;
++      struct ext3_ext_cache *cex;/* last found extent */
++      struct ext3_extents_helpers *ops;
++};
++
++struct ext3_extents_helpers {
++      int (*get_write_access)(handle_t *h, void *buffer);
++      int (*mark_buffer_dirty)(handle_t *h, void *buffer);
++      int (*mergable)(struct ext3_extent *ex1, struct ext3_extent *ex2);
++      int (*remove_extent_credits)(struct ext3_extents_tree *,
++                                   struct ext3_extent *, unsigned long,
++                                   unsigned long);
++      int (*remove_extent)(struct ext3_extents_tree *,
++                           struct ext3_extent *, unsigned long,
++                           unsigned long);
++      int (*new_block)(handle_t *, struct ext3_extents_tree *,
++                       struct ext3_ext_path *, struct ext3_extent *,
++                       int *);
++};
++
++/*
++ * to be called by ext3_ext_walk_space()
++ * negative retcode - error
++ * positive retcode - signal for ext3_ext_walk_space(), see below
++ * callback must return valid extent (passed or newly created)
++ */
++typedef int (*ext_prepare_callback)(struct ext3_extents_tree *,
++                                  struct ext3_ext_path *,
++                                  struct ext3_ext_cache *);
++
++#define EXT_CONTINUE  0
++#define EXT_BREAK     1
++#define EXT_REPEAT    2
++
++
++#define EXT_MAX_BLOCK 0xffffffff
++
++
++#define EXT_FIRST_EXTENT(__hdr__) \
++      ((struct ext3_extent *) (((char *) (__hdr__)) +         \
++                               sizeof(struct ext3_extent_header)))
++#define EXT_FIRST_INDEX(__hdr__) \
++      ((struct ext3_extent_idx *) (((char *) (__hdr__)) +     \
++                                   sizeof(struct ext3_extent_header)))
++#define EXT_HAS_FREE_INDEX(__path__) \
++      ((__path__)->p_hdr->eh_entries < (__path__)->p_hdr->eh_max)
++#define EXT_LAST_EXTENT(__hdr__) \
++      (EXT_FIRST_EXTENT((__hdr__)) + (__hdr__)->eh_entries - 1)
++#define EXT_LAST_INDEX(__hdr__) \
++      (EXT_FIRST_INDEX((__hdr__)) + (__hdr__)->eh_entries - 1)
++#define EXT_MAX_EXTENT(__hdr__) \
++      (EXT_FIRST_EXTENT((__hdr__)) + (__hdr__)->eh_max - 1)
++#define EXT_MAX_INDEX(__hdr__) \
++      (EXT_FIRST_INDEX((__hdr__)) + (__hdr__)->eh_max - 1)
++#define EXT_HDR_GEN(__hdr__)  ((__hdr__)->eh_generation & 0x00ffffff)
++#define EXT_FLAGS(__hdr__)    ((__hdr__)->eh_generation >> 24)
++#define EXT_FLAGS_CLR_UNKNOWN 0x7     /* Flags cleared on modification */
++
++#define EXT_BLOCK_HDR(__bh__)         ((struct ext3_extent_header *)(__bh__)->b_data)
++#define EXT_ROOT_HDR(__tree__)        ((struct ext3_extent_header *)(__tree__)->root)
++#define EXT_DEPTH(__tree__)   (EXT_ROOT_HDR(__tree__)->eh_depth)
++#define EXT_GENERATION(__tree__) EXT_HDR_GEN(EXT_ROOT_HDR(__tree__))
++
++#define EXT_ASSERT(__x__) if (!(__x__)) BUG();
++
++#define EXT_CHECK_PATH(tree,path)                                     \
++{                                                                     \
++      int depth = EXT_DEPTH(tree);                                    \
++      BUG_ON((unsigned long) (path) < __PAGE_OFFSET);                 \
++      BUG_ON((unsigned long) (path)[depth].p_idx <                    \
++                      __PAGE_OFFSET && (path)[depth].p_idx != NULL);  \
++      BUG_ON((unsigned long) (path)[depth].p_ext <                    \
++                      __PAGE_OFFSET && (path)[depth].p_ext != NULL);  \
++      BUG_ON((unsigned long) (path)[depth].p_hdr < __PAGE_OFFSET);    \
++      BUG_ON((unsigned long) (path)[depth].p_bh < __PAGE_OFFSET       \
++                      && depth != 0);                                 \
++      BUG_ON((path)[0].p_depth != depth);                             \
++}
++
++
++/*
++ * this structure is used to gather extents from the tree via ioctl
++ */
++struct ext3_extent_buf {
++      unsigned long start;
++      int buflen;
++      void *buffer;
++      void *cur;
++      int err;
++};
++
++/*
++ * this structure is used to collect stats info about the tree
++ */
++struct ext3_extent_tree_stats {
++      int depth;
++      int extents_num;
++      int leaf_num;
++};
++
++extern void ext3_init_tree_desc(struct ext3_extents_tree *, struct inode *);
++extern int ext3_extent_tree_init(handle_t *, struct ext3_extents_tree *);
++extern int ext3_ext_calc_credits_for_insert(struct ext3_extents_tree *, struct ext3_ext_path *);
++extern int ext3_ext_insert_extent(handle_t *, struct ext3_extents_tree *, struct ext3_ext_path *, struct ext3_extent *);
++extern int ext3_ext_walk_space(struct ext3_extents_tree *, unsigned long, unsigned long, ext_prepare_callback);
++extern int ext3_ext_remove_space(struct ext3_extents_tree *, unsigned long, unsigned long);
++extern struct ext3_ext_path * ext3_ext_find_extent(struct ext3_extents_tree *, int, struct ext3_ext_path *);
++extern int ext3_ext_calc_blockmap_metadata(struct inode *, int);
++
++static inline void
++ext3_ext_invalidate_cache(struct ext3_extents_tree *tree)
++{
++      if (tree->cex)
++              tree->cex->ec_type = EXT3_EXT_CACHE_NO;
++}
++
++
++#endif /* _LINUX_EXT3_EXTENTS */
+Index: linux-2.6.16.27-0.9/include/linux/ext3_fs_i.h
+===================================================================
+--- linux-2.6.16.27-0.9.orig/include/linux/ext3_fs_i.h
++++ linux-2.6.16.27-0.9/include/linux/ext3_fs_i.h
+@@ -133,6 +133,8 @@ struct ext3_inode_info {
+        */
+       struct semaphore truncate_sem;
+       struct inode vfs_inode;
++
++      __u32 i_cached_extent[4];
+ };
+ #endif        /* _LINUX_EXT3_FS_I */
index bfba5fb..18a2997 100644 (file)
@@ -4,7 +4,7 @@ iopen-2.6-fc5.patch
 ext3-map_inode_page-2.6-suse.patch
 export-ext3-2.6-rhel4.patch
 ext3-include-fixes-2.6-rhel4.patch
-ext3-extents-2.6.15.patch
+ext3-extents-2.6.16-sles10.patch
 ext3-mballoc2-2.6-fc5.patch
 ext3-nlinks-2.6.9.patch
 ext3-ialloc-2.6.patch
diff --git a/lustre/kernel_patches/patches/ext3-extents-2.6.16-sles10.patch b/lustre/kernel_patches/patches/ext3-extents-2.6.16-sles10.patch
new file mode 100644 (file)
index 0000000..fd17dab
--- /dev/null
@@ -0,0 +1,2947 @@
+Index: linux-2.6.16.27-0.9/fs/ext3/extents.c
+===================================================================
+--- /dev/null
++++ linux-2.6.16.27-0.9/fs/ext3/extents.c
+@@ -0,0 +1,2359 @@
++/*
++ * Copyright(c) 2003, 2004, 2005, Cluster File Systems, Inc, info@clusterfs.com
++ * Written by Alex Tomas <alex@clusterfs.com>
++ *
++ * This program is free software; you can redistribute it and/or modify
++ * it under the terms of the GNU General Public License version 2 as
++ * published by the Free Software Foundation.
++ *
++ * This program is distributed in the hope that it will be useful,
++ * but WITHOUT ANY WARRANTY; without even the implied warranty of
++ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
++ * GNU General Public License for more details.
++ *
++ * You should have received a copy of the GNU General Public Licens
++ * along with this program; if not, write to the Free Software
++ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-
++ */
++
++/*
++ * Extents support for EXT3
++ *
++ * TODO:
++ *   - ext3_ext_walk_space() sould not use ext3_ext_find_extent()
++ *   - ext3_ext_calc_credits() could take 'mergable' into account
++ *   - ext3*_error() should be used in some situations
++ *   - find_goal() [to be tested and improved]
++ *   - smart tree reduction
++ *   - arch-independence
++ *     common on-disk format for big/little-endian arch
++ */
++
++#include <linux/module.h>
++#include <linux/fs.h>
++#include <linux/time.h>
++#include <linux/ext3_jbd.h>
++#include <linux/jbd.h>
++#include <linux/smp_lock.h>
++#include <linux/highuid.h>
++#include <linux/pagemap.h>
++#include <linux/quotaops.h>
++#include <linux/string.h>
++#include <linux/slab.h>
++#include <linux/ext3_extents.h>
++#include <asm/uaccess.h>
++
++
++static inline int ext3_ext_check_header(struct ext3_extent_header *eh)
++{
++      if (eh->eh_magic != EXT3_EXT_MAGIC) {
++              printk(KERN_ERR "EXT3-fs: invalid magic = 0x%x\n",
++                     (unsigned)eh->eh_magic);
++              return -EIO;
++      }
++      if (eh->eh_max == 0) {
++              printk(KERN_ERR "EXT3-fs: invalid eh_max = %u\n",
++                     (unsigned)eh->eh_max);
++              return -EIO;
++      }
++      if (eh->eh_entries > eh->eh_max) {
++              printk(KERN_ERR "EXT3-fs: invalid eh_entries = %u\n",
++                     (unsigned)eh->eh_entries);
++              return -EIO;
++      }
++      return 0;
++}
++
++static handle_t *ext3_ext_journal_restart(handle_t *handle, int needed)
++{
++      int err;
++
++      if (handle->h_buffer_credits > needed)
++              return handle;
++      if (!ext3_journal_extend(handle, needed))
++              return handle;
++      err = ext3_journal_restart(handle, needed);
++      
++      return handle;
++}
++
++static int inline
++ext3_ext_get_access_for_root(handle_t *h, struct ext3_extents_tree *tree)
++{
++      if (tree->ops->get_write_access)
++              return tree->ops->get_write_access(h,tree->buffer);
++      else
++              return 0;
++}
++
++static int inline
++ext3_ext_mark_root_dirty(handle_t *h, struct ext3_extents_tree *tree)
++{
++      if (tree->ops->mark_buffer_dirty)
++              return tree->ops->mark_buffer_dirty(h,tree->buffer);
++      else
++              return 0;
++}
++
++/*
++ * could return:
++ *  - EROFS
++ *  - ENOMEM
++ */
++static int ext3_ext_get_access(handle_t *handle,
++                             struct ext3_extents_tree *tree,
++                             struct ext3_ext_path *path)
++{
++      int err;
++
++      if (path->p_bh) {
++              /* path points to block */
++              err = ext3_journal_get_write_access(handle, path->p_bh);
++      } else {
++              /* path points to leaf/index in inode body */
++              err = ext3_ext_get_access_for_root(handle, tree);
++      }
++      return err;
++}
++
++/*
++ * could return:
++ *  - EROFS
++ *  - ENOMEM
++ *  - EIO
++ */
++static int ext3_ext_dirty(handle_t *handle, struct ext3_extents_tree *tree,
++                        struct ext3_ext_path *path)
++{
++      int err;
++      if (path->p_bh) {
++              /* path points to block */
++              err =ext3_journal_dirty_metadata(handle, path->p_bh);
++      } else {
++              /* path points to leaf/index in inode body */
++              err = ext3_ext_mark_root_dirty(handle, tree);
++      }
++      return err;
++}
++
++static int inline
++ext3_ext_new_block(handle_t *handle, struct ext3_extents_tree *tree,
++                 struct ext3_ext_path *path, struct ext3_extent *ex,
++                 int *err)
++{
++      int goal, depth, newblock;
++      struct inode *inode;
++
++      EXT_ASSERT(tree);
++      if (tree->ops->new_block)
++              return tree->ops->new_block(handle, tree, path, ex, err);
++
++      inode = tree->inode;
++      depth = EXT_DEPTH(tree);
++      if (path && depth > 0) {
++              goal = path[depth-1].p_block;
++      } else {
++              struct ext3_inode_info *ei = EXT3_I(inode);
++              unsigned long bg_start;
++              unsigned long colour;
++
++              bg_start = (ei->i_block_group *
++                          EXT3_BLOCKS_PER_GROUP(inode->i_sb)) +
++                      le32_to_cpu(EXT3_SB(inode->i_sb)->s_es->s_first_data_block);
++              colour = (current->pid % 16) *
++                      (EXT3_BLOCKS_PER_GROUP(inode->i_sb) / 16);
++              goal = bg_start + colour;
++      }
++
++      newblock = ext3_new_block(handle, inode, goal, err);
++      return newblock;
++}
++
++static inline void ext3_ext_tree_changed(struct ext3_extents_tree *tree)
++{
++      struct ext3_extent_header *neh = EXT_ROOT_HDR(tree);
++      neh->eh_generation = ((EXT_FLAGS(neh) & ~EXT_FLAGS_CLR_UNKNOWN) << 24) |
++                           (EXT_HDR_GEN(neh) + 1);
++}
++
++static inline int ext3_ext_space_block(struct ext3_extents_tree *tree)
++{
++      int size;
++
++      size = (tree->inode->i_sb->s_blocksize -
++              sizeof(struct ext3_extent_header)) /
++                              sizeof(struct ext3_extent);
++#ifdef AGRESSIVE_TEST
++      size = 6;
++#endif
++      return size;
++}
++
++static inline int ext3_ext_space_block_idx(struct ext3_extents_tree *tree)
++{
++      int size;
++
++      size = (tree->inode->i_sb->s_blocksize -
++              sizeof(struct ext3_extent_header)) /
++                              sizeof(struct ext3_extent_idx);
++#ifdef AGRESSIVE_TEST
++      size = 5;
++#endif
++      return size;
++}
++
++static inline int ext3_ext_space_root(struct ext3_extents_tree *tree)
++{
++      int size;
++
++      size = (tree->buffer_len - sizeof(struct ext3_extent_header)) /
++                      sizeof(struct ext3_extent);
++#ifdef AGRESSIVE_TEST
++      size = 3;
++#endif
++      return size;
++}
++
++static inline int ext3_ext_space_root_idx(struct ext3_extents_tree *tree)
++{
++      int size;
++
++      size = (tree->buffer_len - sizeof(struct ext3_extent_header)) /
++                      sizeof(struct ext3_extent_idx);
++#ifdef AGRESSIVE_TEST
++      size = 4;
++#endif
++      return size;
++}
++
++static void ext3_ext_show_path(struct ext3_extents_tree *tree,
++                             struct ext3_ext_path *path)
++{
++#ifdef EXT_DEBUG
++      int k, l = path->p_depth;
++
++      ext_debug(tree, "path:");
++      for (k = 0; k <= l; k++, path++) {
++              if (path->p_idx) {
++                      ext_debug(tree, "  %d->%d", path->p_idx->ei_block,
++                                path->p_idx->ei_leaf);
++              } else if (path->p_ext) {
++                      ext_debug(tree, "  %d:%d:%d",
++                                path->p_ext->ee_block,
++                                path->p_ext->ee_len,
++                                path->p_ext->ee_start);
++              } else
++                      ext_debug(tree, "  []");
++      }
++      ext_debug(tree, "\n");
++#endif
++}
++
++static void ext3_ext_show_leaf(struct ext3_extents_tree *tree,
++                             struct ext3_ext_path *path)
++{
++#ifdef EXT_DEBUG
++      int depth = EXT_DEPTH(tree);
++      struct ext3_extent_header *eh;
++      struct ext3_extent *ex;
++      int i;
++
++      if (!path)
++              return;
++
++      eh = path[depth].p_hdr;
++      ex = EXT_FIRST_EXTENT(eh);
++
++      for (i = 0; i < eh->eh_entries; i++, ex++) {
++              ext_debug(tree, "%d:%d:%d ",
++                        ex->ee_block, ex->ee_len, ex->ee_start);
++      }
++      ext_debug(tree, "\n");
++#endif
++}
++
++static void ext3_ext_drop_refs(struct ext3_ext_path *path)
++{
++      int depth = path->p_depth;
++      int i;
++
++      for (i = 0; i <= depth; i++, path++) {
++              if (path->p_bh) {
++                      brelse(path->p_bh);
++                      path->p_bh = NULL;
++              }
++      }
++}
++
++/*
++ * binary search for closest index by given block
++ */
++static inline void
++ext3_ext_binsearch_idx(struct ext3_extents_tree *tree,
++                     struct ext3_ext_path *path, int block)
++{
++      struct ext3_extent_header *eh = path->p_hdr;
++      struct ext3_extent_idx *ix;
++      int l = 0, k, r;
++
++      EXT_ASSERT(eh->eh_magic == EXT3_EXT_MAGIC);
++      EXT_ASSERT(eh->eh_entries <= eh->eh_max);
++      EXT_ASSERT(eh->eh_entries > 0);
++
++      ext_debug(tree, "binsearch for %d(idx):  ", block);
++
++      path->p_idx = ix = EXT_FIRST_INDEX(eh);
++
++      r = k = eh->eh_entries;
++      while (k > 1) {
++              k = (r - l) / 2;
++              if (block < ix[l + k].ei_block)
++                      r -= k;
++              else
++                      l += k;
++              ext_debug(tree, "%d:%d:%d ", k, l, r);
++      }
++
++      ix += l;
++      path->p_idx = ix;
++      ext_debug(tree," -> %d->%d ",path->p_idx->ei_block,path->p_idx->ei_leaf);
++
++      while (l++ < r) {
++              if (block < ix->ei_block) 
++                      break;
++              path->p_idx = ix++;
++      }
++      ext_debug(tree, "  -> %d->%d\n", path->p_idx->ei_block,
++                path->p_idx->ei_leaf);
++
++#ifdef CHECK_BINSEARCH 
++      {
++              struct ext3_extent_idx *chix;
++
++              chix = ix = EXT_FIRST_INDEX(eh);
++              for (k = 0; k < eh->eh_entries; k++, ix++) {
++                      if (k != 0 && ix->ei_block <= ix[-1].ei_block) {
++                              printk("k=%d, ix=0x%p, first=0x%p\n", k,
++                                     ix, EXT_FIRST_INDEX(eh));
++                              printk("%u <= %u\n",
++                                     ix->ei_block,ix[-1].ei_block);
++                      }
++                      EXT_ASSERT(k == 0 || ix->ei_block > ix[-1].ei_block);
++                      if (block < ix->ei_block) 
++                              break;
++                      chix = ix;
++              }
++              EXT_ASSERT(chix == path->p_idx);
++      }
++#endif
++}
++
++/*
++ * binary search for closest extent by given block
++ */
++static inline void
++ext3_ext_binsearch(struct ext3_extents_tree *tree,
++                 struct ext3_ext_path *path, int block)
++{
++      struct ext3_extent_header *eh = path->p_hdr;
++      struct ext3_extent *ex;
++      int l = 0, k, r;
++
++      EXT_ASSERT(eh->eh_magic == EXT3_EXT_MAGIC);
++      EXT_ASSERT(eh->eh_entries <= eh->eh_max);
++
++      if (eh->eh_entries == 0) {
++              /*
++               * this leaf is empty yet:
++               *  we get such a leaf in split/add case
++               */
++              return;
++      }
++      
++      ext_debug(tree, "binsearch for %d:  ", block);
++
++      path->p_ext = ex = EXT_FIRST_EXTENT(eh);
++
++      r = k = eh->eh_entries;
++      while (k > 1) {
++              k = (r - l) / 2;
++              if (block < ex[l + k].ee_block)
++                      r -= k;
++              else
++                      l += k;
++              ext_debug(tree, "%d:%d:%d ", k, l, r);
++      }
++
++      ex += l;
++      path->p_ext = ex;
++      ext_debug(tree, "  -> %d:%d:%d ", path->p_ext->ee_block,
++                path->p_ext->ee_start, path->p_ext->ee_len);
++
++      while (l++ < r) {
++              if (block < ex->ee_block) 
++                      break;
++              path->p_ext = ex++;
++      }
++      ext_debug(tree, "  -> %d:%d:%d\n", path->p_ext->ee_block,
++                path->p_ext->ee_start, path->p_ext->ee_len);
++
++#ifdef CHECK_BINSEARCH 
++      {
++              struct ext3_extent *chex;
++
++              chex = ex = EXT_FIRST_EXTENT(eh);
++              for (k = 0; k < eh->eh_entries; k++, ex++) {
++                      EXT_ASSERT(k == 0 || ex->ee_block > ex[-1].ee_block);
++                      if (block < ex->ee_block) 
++                              break;
++                      chex = ex;
++              }
++              EXT_ASSERT(chex == path->p_ext);
++      }
++#endif
++}
++
++int ext3_extent_tree_init(handle_t *handle, struct ext3_extents_tree *tree)
++{
++      struct ext3_extent_header *eh;
++
++      BUG_ON(tree->buffer_len == 0);
++      ext3_ext_get_access_for_root(handle, tree);
++      eh = EXT_ROOT_HDR(tree);
++      eh->eh_depth = 0;
++      eh->eh_entries = 0;
++      eh->eh_magic = EXT3_EXT_MAGIC;
++      eh->eh_max = ext3_ext_space_root(tree);
++      ext3_ext_mark_root_dirty(handle, tree);
++      ext3_ext_invalidate_cache(tree);
++      return 0;
++}
++
++struct ext3_ext_path *
++ext3_ext_find_extent(struct ext3_extents_tree *tree, int block,
++                   struct ext3_ext_path *path)
++{
++      struct ext3_extent_header *eh;
++      struct buffer_head *bh;
++      int depth, i, ppos = 0;
++
++      EXT_ASSERT(tree);
++      EXT_ASSERT(tree->inode);
++      EXT_ASSERT(tree->root);
++
++      eh = EXT_ROOT_HDR(tree);
++      EXT_ASSERT(eh);
++      if (ext3_ext_check_header(eh)) {
++              /* don't free previously allocated path
++               * -- caller should take care */
++              path = NULL;
++              goto err;
++      }
++
++      i = depth = EXT_DEPTH(tree);
++      EXT_ASSERT(eh->eh_max);
++      EXT_ASSERT(eh->eh_magic == EXT3_EXT_MAGIC);
++      
++      /* account possible depth increase */
++      if (!path) {
++              path = kmalloc(sizeof(struct ext3_ext_path) * (depth + 2),
++                             GFP_NOFS);
++              if (!path)
++                      return ERR_PTR(-ENOMEM);
++      }
++      memset(path, 0, sizeof(struct ext3_ext_path) * (depth + 1));
++      path[0].p_hdr = eh;
++
++      /* walk through the tree */
++      while (i) {
++              ext_debug(tree, "depth %d: num %d, max %d\n",
++                        ppos, eh->eh_entries, eh->eh_max);
++              ext3_ext_binsearch_idx(tree, path + ppos, block);
++              path[ppos].p_block = path[ppos].p_idx->ei_leaf;
++              path[ppos].p_depth = i;
++              path[ppos].p_ext = NULL;
++
++              bh = sb_bread(tree->inode->i_sb, path[ppos].p_block);
++              if (!bh)
++                      goto err;
++
++              eh = EXT_BLOCK_HDR(bh);
++              ppos++;
++              EXT_ASSERT(ppos <= depth);
++              path[ppos].p_bh = bh;
++              path[ppos].p_hdr = eh;
++              i--;
++
++              if (ext3_ext_check_header(eh))
++                      goto err;
++      }
++
++      path[ppos].p_depth = i;
++      path[ppos].p_hdr = eh;
++      path[ppos].p_ext = NULL;
++      path[ppos].p_idx = NULL;
++
++      if (ext3_ext_check_header(eh))
++              goto err;
++
++      /* find extent */
++      ext3_ext_binsearch(tree, path + ppos, block);
++
++      ext3_ext_show_path(tree, path);
++
++      return path;
++
++err:
++      printk(KERN_ERR "EXT3-fs: header is corrupted!\n");
++      if (path) {
++              ext3_ext_drop_refs(path);
++              kfree(path);
++      }
++      return ERR_PTR(-EIO);
++}
++
++/*
++ * insert new index [logical;ptr] into the block at cupr
++ * it check where to insert: before curp or after curp
++ */
++static int ext3_ext_insert_index(handle_t *handle,
++                               struct ext3_extents_tree *tree,
++                               struct ext3_ext_path *curp,
++                               int logical, int ptr)
++{
++      struct ext3_extent_idx *ix;
++      int len, err;
++
++      if ((err = ext3_ext_get_access(handle, tree, curp)))
++              return err;
++
++      EXT_ASSERT(logical != curp->p_idx->ei_block);
++      len = EXT_MAX_INDEX(curp->p_hdr) - curp->p_idx;
++      if (logical > curp->p_idx->ei_block) {
++              /* insert after */
++              if (curp->p_idx != EXT_LAST_INDEX(curp->p_hdr)) {
++                      len = (len - 1) * sizeof(struct ext3_extent_idx);
++                      len = len < 0 ? 0 : len;
++                      ext_debug(tree, "insert new index %d after: %d. "
++                                "move %d from 0x%p to 0x%p\n",
++                                logical, ptr, len,
++                                (curp->p_idx + 1), (curp->p_idx + 2));
++                      memmove(curp->p_idx + 2, curp->p_idx + 1, len);
++              }
++              ix = curp->p_idx + 1;
++      } else {
++              /* insert before */
++              len = len * sizeof(struct ext3_extent_idx);
++              len = len < 0 ? 0 : len;
++              ext_debug(tree, "insert new index %d before: %d. "
++                        "move %d from 0x%p to 0x%p\n",
++                        logical, ptr, len,
++                        curp->p_idx, (curp->p_idx + 1));
++              memmove(curp->p_idx + 1, curp->p_idx, len);
++              ix = curp->p_idx;
++      }
++
++      ix->ei_block = logical;
++      ix->ei_leaf = ptr;
++      ix->ei_leaf_hi = ix->ei_unused = 0;
++      curp->p_hdr->eh_entries++;
++
++      EXT_ASSERT(curp->p_hdr->eh_entries <= curp->p_hdr->eh_max);
++      EXT_ASSERT(ix <= EXT_LAST_INDEX(curp->p_hdr));
++
++      err = ext3_ext_dirty(handle, tree, curp);
++      ext3_std_error(tree->inode->i_sb, err);
++
++      return err;
++}
++
++/*
++ * routine inserts new subtree into the path, using free index entry
++ * at depth 'at:
++ *  - allocates all needed blocks (new leaf and all intermediate index blocks)
++ *  - makes decision where to split
++ *  - moves remaining extens and index entries (right to the split point)
++ *    into the newly allocated blocks
++ *  - initialize subtree
++ */
++static int ext3_ext_split(handle_t *handle, struct ext3_extents_tree *tree,
++                        struct ext3_ext_path *path,
++                        struct ext3_extent *newext, int at)
++{
++      struct buffer_head *bh = NULL;
++      int depth = EXT_DEPTH(tree);
++      struct ext3_extent_header *neh;
++      struct ext3_extent_idx *fidx;
++      struct ext3_extent *ex;
++      int i = at, k, m, a;
++      unsigned long newblock, oldblock, border;
++      int *ablocks = NULL; /* array of allocated blocks */
++      int err = 0;
++
++      /* make decision: where to split? */
++      /* FIXME: now desicion is simplest: at current extent */
++
++      /* if current leaf will be splitted, then we should use 
++       * border from split point */
++      EXT_ASSERT(path[depth].p_ext <= EXT_MAX_EXTENT(path[depth].p_hdr));
++      if (path[depth].p_ext != EXT_MAX_EXTENT(path[depth].p_hdr)) {
++              border = path[depth].p_ext[1].ee_block;
++              ext_debug(tree, "leaf will be splitted."
++                        " next leaf starts at %d\n",
++                        (int)border);
++      } else {
++              border = newext->ee_block;
++              ext_debug(tree, "leaf will be added."
++                        " next leaf starts at %d\n",
++                        (int)border);
++      }
++
++      /* 
++       * if error occurs, then we break processing
++       * and turn filesystem read-only. so, index won't
++       * be inserted and tree will be in consistent
++       * state. next mount will repair buffers too
++       */
++
++      /*
++       * get array to track all allocated blocks
++       * we need this to handle errors and free blocks
++       * upon them
++       */
++      ablocks = kmalloc(sizeof(unsigned long) * depth, GFP_NOFS);
++      if (!ablocks)
++              return -ENOMEM;
++      memset(ablocks, 0, sizeof(unsigned long) * depth);
++
++      /* allocate all needed blocks */
++      ext_debug(tree, "allocate %d blocks for indexes/leaf\n", depth - at);
++      for (a = 0; a < depth - at; a++) {
++              newblock = ext3_ext_new_block(handle, tree, path, newext, &err);
++              if (newblock == 0)
++                      goto cleanup;
++              ablocks[a] = newblock;
++      }
++
++      /* initialize new leaf */
++      newblock = ablocks[--a];
++      EXT_ASSERT(newblock);
++      bh = sb_getblk(tree->inode->i_sb, newblock);
++      if (!bh) {
++              err = -EIO;
++              goto cleanup;
++      }
++      lock_buffer(bh);
++
++      if ((err = ext3_journal_get_create_access(handle, bh)))
++              goto cleanup;
++
++      neh = EXT_BLOCK_HDR(bh);
++      neh->eh_entries = 0;
++      neh->eh_max = ext3_ext_space_block(tree);
++      neh->eh_magic = EXT3_EXT_MAGIC;
++      neh->eh_depth = 0;
++      ex = EXT_FIRST_EXTENT(neh);
++
++      /* move remain of path[depth] to the new leaf */
++      EXT_ASSERT(path[depth].p_hdr->eh_entries == path[depth].p_hdr->eh_max);
++      /* start copy from next extent */
++      /* TODO: we could do it by single memmove */
++      m = 0;
++      path[depth].p_ext++;
++      while (path[depth].p_ext <=
++                      EXT_MAX_EXTENT(path[depth].p_hdr)) {
++              ext_debug(tree, "move %d:%d:%d in new leaf %lu\n",
++                        path[depth].p_ext->ee_block,
++                        path[depth].p_ext->ee_start,
++                        path[depth].p_ext->ee_len,
++                        newblock);
++              memmove(ex++, path[depth].p_ext++, sizeof(struct ext3_extent));
++              neh->eh_entries++;
++              m++;
++      }
++      set_buffer_uptodate(bh);
++      unlock_buffer(bh);
++
++      if ((err = ext3_journal_dirty_metadata(handle, bh)))
++              goto cleanup;   
++      brelse(bh);
++      bh = NULL;
++
++      /* correct old leaf */
++      if (m) {
++              if ((err = ext3_ext_get_access(handle, tree, path + depth)))
++                      goto cleanup;
++              path[depth].p_hdr->eh_entries -= m;
++              if ((err = ext3_ext_dirty(handle, tree, path + depth)))
++                      goto cleanup;
++              
++      }
++
++      /* create intermediate indexes */
++      k = depth - at - 1;
++      EXT_ASSERT(k >= 0);
++      if (k)
++              ext_debug(tree, "create %d intermediate indices\n", k);
++      /* insert new index into current index block */
++      /* current depth stored in i var */
++      i = depth - 1;
++      while (k--) {
++              oldblock = newblock;
++              newblock = ablocks[--a];
++              bh = sb_getblk(tree->inode->i_sb, newblock);
++              if (!bh) {
++                      err = -EIO;
++                      goto cleanup;
++              }
++              lock_buffer(bh);
++
++              if ((err = ext3_journal_get_create_access(handle, bh)))
++                      goto cleanup;
++
++              neh = EXT_BLOCK_HDR(bh);
++              neh->eh_entries = 1;
++              neh->eh_magic = EXT3_EXT_MAGIC;
++              neh->eh_max = ext3_ext_space_block_idx(tree);
++              neh->eh_depth = depth - i; 
++              fidx = EXT_FIRST_INDEX(neh);
++              fidx->ei_block = border;
++              fidx->ei_leaf = oldblock;
++              fidx->ei_leaf_hi = fidx->ei_unused = 0;
++
++              ext_debug(tree, "int.index at %d (block %lu): %lu -> %lu\n",
++                        i, newblock, border, oldblock);
++              /* copy indexes */
++              m = 0;
++              path[i].p_idx++;
++
++              ext_debug(tree, "cur 0x%p, last 0x%p\n", path[i].p_idx,
++                        EXT_MAX_INDEX(path[i].p_hdr));
++              EXT_ASSERT(EXT_MAX_INDEX(path[i].p_hdr) ==
++                         EXT_LAST_INDEX(path[i].p_hdr));
++              while (path[i].p_idx <= EXT_MAX_INDEX(path[i].p_hdr)) {
++                      ext_debug(tree, "%d: move %d:%d in new index %lu\n",
++                                i, path[i].p_idx->ei_block,
++                                path[i].p_idx->ei_leaf, newblock);
++                      memmove(++fidx, path[i].p_idx++,
++                              sizeof(struct ext3_extent_idx));
++                      neh->eh_entries++;
++                      EXT_ASSERT(neh->eh_entries <= neh->eh_max);
++                      m++;
++              }
++              set_buffer_uptodate(bh);
++              unlock_buffer(bh);
++
++              if ((err = ext3_journal_dirty_metadata(handle, bh)))
++                      goto cleanup;
++              brelse(bh);
++              bh = NULL;
++
++              /* correct old index */
++              if (m) {
++                      err = ext3_ext_get_access(handle, tree, path + i);
++                      if (err)
++                              goto cleanup;
++                      path[i].p_hdr->eh_entries -= m;
++                      err = ext3_ext_dirty(handle, tree, path + i);
++                      if (err)
++                              goto cleanup;
++              }
++
++              i--;
++      }
++
++      /* insert new index */
++      if (!err)
++              err = ext3_ext_insert_index(handle, tree, path + at,
++                                          border, newblock);
++
++cleanup:
++      if (bh) {
++              if (buffer_locked(bh))
++                      unlock_buffer(bh);
++              brelse(bh);
++      }
++
++      if (err) {
++              /* free all allocated blocks in error case */
++              for (i = 0; i < depth; i++) {
++                      if (!ablocks[i])
++                              continue;
++                      ext3_free_blocks(handle, tree->inode, ablocks[i], 1);
++              }
++      }
++      kfree(ablocks);
++
++      return err;
++}
++
++/*
++ * routine implements tree growing procedure:
++ *  - allocates new block
++ *  - moves top-level data (index block or leaf) into the new block
++ *  - initialize new top-level, creating index that points to the
++ *    just created block
++ */
++static int ext3_ext_grow_indepth(handle_t *handle,
++                               struct ext3_extents_tree *tree,
++                               struct ext3_ext_path *path,
++                               struct ext3_extent *newext)
++{
++      struct ext3_ext_path *curp = path;
++      struct ext3_extent_header *neh;
++      struct ext3_extent_idx *fidx;
++      struct buffer_head *bh;
++      unsigned long newblock;
++      int err = 0;
++
++      newblock = ext3_ext_new_block(handle, tree, path, newext, &err);
++      if (newblock == 0)
++              return err;
++
++      bh = sb_getblk(tree->inode->i_sb, newblock);
++      if (!bh) {
++              err = -EIO;
++              ext3_std_error(tree->inode->i_sb, err);
++              return err;
++      }
++      lock_buffer(bh);
++
++      if ((err = ext3_journal_get_create_access(handle, bh))) {
++              unlock_buffer(bh);
++              goto out;       
++      }
++
++      /* move top-level index/leaf into new block */
++      memmove(bh->b_data, curp->p_hdr, tree->buffer_len);
++
++      /* set size of new block */
++      neh = EXT_BLOCK_HDR(bh);
++      /* old root could have indexes or leaves
++       * so calculate eh_max right way */
++      if (EXT_DEPTH(tree))
++              neh->eh_max = ext3_ext_space_block_idx(tree);
++      else
++              neh->eh_max = ext3_ext_space_block(tree);
++      neh->eh_magic = EXT3_EXT_MAGIC;
++      set_buffer_uptodate(bh);
++      unlock_buffer(bh);
++
++      if ((err = ext3_journal_dirty_metadata(handle, bh)))
++              goto out;
++
++      /* create index in new top-level index: num,max,pointer */
++      if ((err = ext3_ext_get_access(handle, tree, curp)))
++              goto out;
++
++      curp->p_hdr->eh_magic = EXT3_EXT_MAGIC;
++      curp->p_hdr->eh_max = ext3_ext_space_root_idx(tree);
++      curp->p_hdr->eh_entries = 1;
++      curp->p_idx = EXT_FIRST_INDEX(curp->p_hdr);
++      /* FIXME: it works, but actually path[0] can be index */
++      curp->p_idx->ei_block = EXT_FIRST_EXTENT(path[0].p_hdr)->ee_block;
++      curp->p_idx->ei_leaf = newblock;
++      curp->p_idx->ei_leaf_hi = curp->p_idx->ei_unused = 0;
++
++      neh = EXT_ROOT_HDR(tree);
++      fidx = EXT_FIRST_INDEX(neh);
++      ext_debug(tree, "new root: num %d(%d), lblock %d, ptr %d\n",
++                neh->eh_entries, neh->eh_max, fidx->ei_block, fidx->ei_leaf); 
++
++      neh->eh_depth = path->p_depth + 1;
++      err = ext3_ext_dirty(handle, tree, curp);
++out:
++      brelse(bh);
++
++      return err;
++}
++
++/*
++ * routine finds empty index and adds new leaf. if no free index found
++ * then it requests in-depth growing
++ */
++static int ext3_ext_create_new_leaf(handle_t *handle,
++                                  struct ext3_extents_tree *tree,
++                                  struct ext3_ext_path *path,
++                                  struct ext3_extent *newext)
++{
++      struct ext3_ext_path *curp;
++      int depth, i, err = 0;
++
++repeat:
++      i = depth = EXT_DEPTH(tree);
++      
++      /* walk up to the tree and look for free index entry */
++      curp = path + depth;
++      while (i > 0 && !EXT_HAS_FREE_INDEX(curp)) {
++              i--;
++              curp--;
++      }
++
++      /* we use already allocated block for index block
++       * so, subsequent data blocks should be contigoues */
++      if (EXT_HAS_FREE_INDEX(curp)) {
++              /* if we found index with free entry, then use that
++               * entry: create all needed subtree and add new leaf */
++              err = ext3_ext_split(handle, tree, path, newext, i);
++
++              /* refill path */
++              ext3_ext_drop_refs(path);
++              path = ext3_ext_find_extent(tree, newext->ee_block, path);
++              if (IS_ERR(path))
++                      err = PTR_ERR(path);
++      } else {
++              /* tree is full, time to grow in depth */
++              err = ext3_ext_grow_indepth(handle, tree, path, newext);
++
++              /* refill path */
++              ext3_ext_drop_refs(path);
++              path = ext3_ext_find_extent(tree, newext->ee_block, path);
++              if (IS_ERR(path))
++                      err = PTR_ERR(path);
++
++              /*
++               * only first (depth 0 -> 1) produces free space
++               * in all other cases we have to split growed tree
++               */
++              depth = EXT_DEPTH(tree);
++              if (path[depth].p_hdr->eh_entries == path[depth].p_hdr->eh_max) {
++                      /* now we need split */
++                      goto repeat;
++              }
++      }
++
++      if (err)
++              return err;
++
++      return 0;
++}
++
++/*
++ * returns allocated block in subsequent extent or EXT_MAX_BLOCK
++ * NOTE: it consider block number from index entry as
++ * allocated block. thus, index entries have to be consistent
++ * with leafs
++ */
++static unsigned long
++ext3_ext_next_allocated_block(struct ext3_ext_path *path)
++{
++      int depth;
++
++      EXT_ASSERT(path != NULL);
++      depth = path->p_depth;
++
++      if (depth == 0 && path->p_ext == NULL)
++              return EXT_MAX_BLOCK;
++
++      /* FIXME: what if index isn't full ?! */
++      while (depth >= 0) {
++              if (depth == path->p_depth) {
++                      /* leaf */
++                      if (path[depth].p_ext !=
++                          EXT_LAST_EXTENT(path[depth].p_hdr))
++                              return path[depth].p_ext[1].ee_block;
++              } else {
++                      /* index */
++                      if (path[depth].p_idx !=
++                          EXT_LAST_INDEX(path[depth].p_hdr))
++                              return path[depth].p_idx[1].ei_block;
++              }
++              depth--;        
++      }
++
++      return EXT_MAX_BLOCK;
++}
++
++/*
++ * returns first allocated block from next leaf or EXT_MAX_BLOCK
++ */
++static unsigned ext3_ext_next_leaf_block(struct ext3_extents_tree *tree,
++                                       struct ext3_ext_path *path)
++{
++      int depth;
++
++      EXT_ASSERT(path != NULL);
++      depth = path->p_depth;
++
++      /* zero-tree has no leaf blocks at all */
++      if (depth == 0)
++              return EXT_MAX_BLOCK;
++
++      /* go to index block */
++      depth--;
++      
++      while (depth >= 0) {
++              if (path[depth].p_idx !=
++                  EXT_LAST_INDEX(path[depth].p_hdr))
++                      return path[depth].p_idx[1].ei_block;
++              depth--;        
++      }
++
++      return EXT_MAX_BLOCK;
++}
++
++/*
++ * if leaf gets modified and modified extent is first in the leaf
++ * then we have to correct all indexes above
++ * TODO: do we need to correct tree in all cases?
++ */
++int ext3_ext_correct_indexes(handle_t *handle, struct ext3_extents_tree *tree,
++                           struct ext3_ext_path *path)
++{
++      struct ext3_extent_header *eh;
++      int depth = EXT_DEPTH(tree);    
++      struct ext3_extent *ex;
++      unsigned long border;
++      int k, err = 0;
++      
++      eh = path[depth].p_hdr;
++      ex = path[depth].p_ext;
++      EXT_ASSERT(ex);
++      EXT_ASSERT(eh);
++      
++      if (depth == 0) {
++              /* there is no tree at all */
++              return 0;
++      }
++      
++      if (ex != EXT_FIRST_EXTENT(eh)) {
++              /* we correct tree if first leaf got modified only */
++              return 0;
++      }
++      
++      /*
++       * TODO: we need correction if border is smaller then current one
++       */
++      k = depth - 1;
++      border = path[depth].p_ext->ee_block;
++      if ((err = ext3_ext_get_access(handle, tree, path + k)))
++              return err;
++      path[k].p_idx->ei_block = border;
++      if ((err = ext3_ext_dirty(handle, tree, path + k)))
++              return err;
++
++      while (k--) {
++              /* change all left-side indexes */
++              if (path[k+1].p_idx != EXT_FIRST_INDEX(path[k+1].p_hdr))
++                      break;
++              if ((err = ext3_ext_get_access(handle, tree, path + k)))
++                      break;
++              path[k].p_idx->ei_block = border;
++              if ((err = ext3_ext_dirty(handle, tree, path + k)))
++                      break;
++      }
++
++      return err;
++}
++
++static int inline
++ext3_can_extents_be_merged(struct ext3_extents_tree *tree,
++                         struct ext3_extent *ex1,
++                         struct ext3_extent *ex2)
++{
++      if (ex1->ee_block + ex1->ee_len != ex2->ee_block)
++              return 0;
++
++#ifdef AGRESSIVE_TEST
++      if (ex1->ee_len >= 4)
++              return 0;
++#endif
++
++      if (!tree->ops->mergable)
++              return 1;
++
++      return tree->ops->mergable(ex1, ex2);
++}
++
++/*
++ * this routine tries to merge requsted extent into the existing
++ * extent or inserts requested extent as new one into the tree,
++ * creating new leaf in no-space case
++ */
++int ext3_ext_insert_extent(handle_t *handle, struct ext3_extents_tree *tree,
++                         struct ext3_ext_path *path,
++                         struct ext3_extent *newext)
++{
++      struct ext3_extent_header * eh;
++      struct ext3_extent *ex, *fex;
++      struct ext3_extent *nearex; /* nearest extent */
++      struct ext3_ext_path *npath = NULL;
++      int depth, len, err, next;
++
++      EXT_ASSERT(newext->ee_len > 0);
++      depth = EXT_DEPTH(tree);
++      ex = path[depth].p_ext;
++      EXT_ASSERT(path[depth].p_hdr);
++
++      /* try to insert block into found extent and return */
++      if (ex && ext3_can_extents_be_merged(tree, ex, newext)) {
++              ext_debug(tree, "append %d block to %d:%d (from %d)\n",
++                        newext->ee_len, ex->ee_block, ex->ee_len,
++                        ex->ee_start);
++              if ((err = ext3_ext_get_access(handle, tree, path + depth)))
++                      return err;
++              ex->ee_len += newext->ee_len;
++              eh = path[depth].p_hdr;
++              nearex = ex;
++              goto merge;
++      }
++
++repeat:
++      depth = EXT_DEPTH(tree);
++      eh = path[depth].p_hdr;
++      if (eh->eh_entries < eh->eh_max)
++              goto has_space;
++
++      /* probably next leaf has space for us? */
++      fex = EXT_LAST_EXTENT(eh);
++      next = ext3_ext_next_leaf_block(tree, path);
++      if (newext->ee_block > fex->ee_block && next != EXT_MAX_BLOCK) {
++              ext_debug(tree, "next leaf block - %d\n", next);
++              EXT_ASSERT(!npath);
++              npath = ext3_ext_find_extent(tree, next, NULL);
++              if (IS_ERR(npath))
++                      return PTR_ERR(npath);
++              EXT_ASSERT(npath->p_depth == path->p_depth);
++              eh = npath[depth].p_hdr;
++              if (eh->eh_entries < eh->eh_max) {
++                      ext_debug(tree, "next leaf isnt full(%d)\n",
++                                eh->eh_entries);
++                      path = npath;
++                      goto repeat;
++              }
++              ext_debug(tree, "next leaf hasno free space(%d,%d)\n",
++                        eh->eh_entries, eh->eh_max);
++      }
++
++      /*
++       * there is no free space in found leaf
++       * we're gonna add new leaf in the tree
++       */
++      err = ext3_ext_create_new_leaf(handle, tree, path, newext);
++      if (err)
++              goto cleanup;
++      depth = EXT_DEPTH(tree);
++      eh = path[depth].p_hdr;
++
++has_space:
++      nearex = path[depth].p_ext;
++
++      if ((err = ext3_ext_get_access(handle, tree, path + depth)))
++              goto cleanup;
++
++      if (!nearex) {
++              /* there is no extent in this leaf, create first one */
++              ext_debug(tree, "first extent in the leaf: %d:%d:%d\n",
++                        newext->ee_block, newext->ee_start,
++                        newext->ee_len);
++              path[depth].p_ext = EXT_FIRST_EXTENT(eh);
++      } else if (newext->ee_block > nearex->ee_block) {
++              EXT_ASSERT(newext->ee_block != nearex->ee_block);
++              if (nearex != EXT_LAST_EXTENT(eh)) {
++                      len = EXT_MAX_EXTENT(eh) - nearex;
++                      len = (len - 1) * sizeof(struct ext3_extent);
++                      len = len < 0 ? 0 : len;
++                      ext_debug(tree, "insert %d:%d:%d after: nearest 0x%p, "
++                                "move %d from 0x%p to 0x%p\n",
++                                newext->ee_block, newext->ee_start,
++                                newext->ee_len,
++                                nearex, len, nearex + 1, nearex + 2);
++                      memmove(nearex + 2, nearex + 1, len);
++              }
++              path[depth].p_ext = nearex + 1;
++      } else {
++              EXT_ASSERT(newext->ee_block != nearex->ee_block);
++              len = (EXT_MAX_EXTENT(eh) - nearex) * sizeof(struct ext3_extent);
++              len = len < 0 ? 0 : len;
++              ext_debug(tree, "insert %d:%d:%d before: nearest 0x%p, "
++                        "move %d from 0x%p to 0x%p\n",
++                        newext->ee_block, newext->ee_start, newext->ee_len,
++                        nearex, len, nearex + 1, nearex + 2);
++              memmove(nearex + 1, nearex, len);
++              path[depth].p_ext = nearex;
++      }
++
++      eh->eh_entries++;
++      nearex = path[depth].p_ext;
++      nearex->ee_block = newext->ee_block;
++      nearex->ee_start = newext->ee_start;
++      nearex->ee_len = newext->ee_len;
++      /* FIXME: support for large fs */
++      nearex->ee_start_hi = 0;
++
++merge:
++      /* try to merge extents to the right */
++      while (nearex < EXT_LAST_EXTENT(eh)) {
++              if (!ext3_can_extents_be_merged(tree, nearex, nearex + 1))
++                      break;
++              /* merge with next extent! */
++              nearex->ee_len += nearex[1].ee_len;
++              if (nearex + 1 < EXT_LAST_EXTENT(eh)) {
++                      len = (EXT_LAST_EXTENT(eh) - nearex - 1) *
++                              sizeof(struct ext3_extent);
++                      memmove(nearex + 1, nearex + 2, len);
++              }
++              eh->eh_entries--;
++              EXT_ASSERT(eh->eh_entries > 0);
++      }
++
++      /* try to merge extents to the left */
++
++      /* time to correct all indexes above */
++      err = ext3_ext_correct_indexes(handle, tree, path);
++      if (err)
++              goto cleanup;
++
++      err = ext3_ext_dirty(handle, tree, path + depth);
++
++cleanup:
++      if (npath) {
++              ext3_ext_drop_refs(npath);
++              kfree(npath);
++      }
++      ext3_ext_tree_changed(tree);
++      ext3_ext_invalidate_cache(tree);
++      return err;
++}
++
++int ext3_ext_walk_space(struct ext3_extents_tree *tree, unsigned long block,
++                      unsigned long num, ext_prepare_callback func)
++{
++      struct ext3_ext_path *path = NULL;
++      struct ext3_ext_cache cbex;
++      struct ext3_extent *ex;
++      unsigned long next, start = 0, end = 0;
++      unsigned long last = block + num;
++      int depth, exists, err = 0;
++
++      EXT_ASSERT(tree);
++      EXT_ASSERT(func);
++      EXT_ASSERT(tree->inode);
++      EXT_ASSERT(tree->root);
++
++      while (block < last && block != EXT_MAX_BLOCK) {
++              num = last - block;
++              /* find extent for this block */
++              path = ext3_ext_find_extent(tree, block, path);
++              if (IS_ERR(path)) {
++                      err = PTR_ERR(path);
++                      path = NULL;
++                      break;
++              }
++
++              depth = EXT_DEPTH(tree);
++              EXT_ASSERT(path[depth].p_hdr);
++              ex = path[depth].p_ext;
++              next = ext3_ext_next_allocated_block(path);
++
++              exists = 0;
++              if (!ex) {
++                      /* there is no extent yet, so try to allocate
++                       * all requested space */
++                      start = block;
++                      end = block + num;
++              } else if (ex->ee_block > block) {
++                      /* need to allocate space before found extent */
++                      start = block;
++                      end = ex->ee_block;
++                      if (block + num < end)
++                              end = block + num;
++              } else if (block >= ex->ee_block + ex->ee_len) {
++                      /* need to allocate space after found extent */
++                      start = block;
++                      end = block + num;
++                      if (end >= next)
++                              end = next;
++              } else if (block >= ex->ee_block) {
++                      /* 
++                       * some part of requested space is covered
++                       * by found extent
++                       */
++                      start = block;
++                      end = ex->ee_block + ex->ee_len;
++                      if (block + num < end)
++                              end = block + num;
++                      exists = 1;
++              } else {
++                      BUG();
++              }
++              EXT_ASSERT(end > start);
++
++              if (!exists) {
++                      cbex.ec_block = start;
++                      cbex.ec_len = end - start;
++                      cbex.ec_start = 0;
++                      cbex.ec_type = EXT3_EXT_CACHE_GAP;
++              } else {
++                      cbex.ec_block = ex->ee_block;
++                      cbex.ec_len = ex->ee_len;
++                      cbex.ec_start = ex->ee_start;
++                      cbex.ec_type = EXT3_EXT_CACHE_EXTENT;
++              }
++
++              EXT_ASSERT(cbex.ec_len > 0);
++              EXT_ASSERT(path[depth].p_hdr);
++              err = func(tree, path, &cbex);
++              ext3_ext_drop_refs(path);
++
++              if (err < 0)
++                      break;
++              if (err == EXT_REPEAT)
++                      continue;
++              else if (err == EXT_BREAK) {
++                      err = 0;
++                      break;
++              }
++
++              if (EXT_DEPTH(tree) != depth) {
++                      /* depth was changed. we have to realloc path */
++                      kfree(path);
++                      path = NULL;
++              }
++
++              block = cbex.ec_block + cbex.ec_len;
++      }
++
++      if (path) {
++              ext3_ext_drop_refs(path);
++              kfree(path);
++      }
++
++      return err;
++}
++
++static inline void
++ext3_ext_put_in_cache(struct ext3_extents_tree *tree, __u32 block,
++                    __u32 len, __u32 start, int type)
++{
++      EXT_ASSERT(len > 0);
++      if (tree->cex) {
++              tree->cex->ec_type = type;
++              tree->cex->ec_block = block;
++              tree->cex->ec_len = len;
++              tree->cex->ec_start = start;
++      }
++}
++
++/*
++ * this routine calculate boundaries of the gap requested block fits into
++ * and cache this gap
++ */
++static inline void
++ext3_ext_put_gap_in_cache(struct ext3_extents_tree *tree,
++                        struct ext3_ext_path *path,
++                        unsigned long block)
++{
++      int depth = EXT_DEPTH(tree);
++      unsigned long lblock, len;
++      struct ext3_extent *ex;
++
++      if (!tree->cex)
++              return;
++
++      ex = path[depth].p_ext;
++      if (ex == NULL) {
++              /* there is no extent yet, so gap is [0;-] */
++              lblock = 0;
++              len = EXT_MAX_BLOCK;
++              ext_debug(tree, "cache gap(whole file):");
++      } else if (block < ex->ee_block) {
++              lblock = block;
++              len = ex->ee_block - block;
++              ext_debug(tree, "cache gap(before): %lu [%lu:%lu]",
++                        (unsigned long) block,
++                        (unsigned long) ex->ee_block,
++                        (unsigned long) ex->ee_len);
++      } else if (block >= ex->ee_block + ex->ee_len) {
++              lblock = ex->ee_block + ex->ee_len;
++              len = ext3_ext_next_allocated_block(path);
++              ext_debug(tree, "cache gap(after): [%lu:%lu] %lu",
++                        (unsigned long) ex->ee_block,
++                        (unsigned long) ex->ee_len,
++                        (unsigned long) block);
++              EXT_ASSERT(len > lblock);
++              len = len - lblock;
++      } else {
++              lblock = len = 0;
++              BUG();
++      }
++
++      ext_debug(tree, " -> %lu:%lu\n", (unsigned long) lblock, len);
++      ext3_ext_put_in_cache(tree, lblock, len, 0, EXT3_EXT_CACHE_GAP);
++}
++
++static inline int
++ext3_ext_in_cache(struct ext3_extents_tree *tree, unsigned long block,
++                struct ext3_extent *ex)
++{
++      struct ext3_ext_cache *cex = tree->cex;
++
++      /* is there cache storage at all? */
++      if (!cex)
++              return EXT3_EXT_CACHE_NO;
++
++      /* has cache valid data? */
++      if (cex->ec_type == EXT3_EXT_CACHE_NO)
++              return EXT3_EXT_CACHE_NO;
++
++      EXT_ASSERT(cex->ec_type == EXT3_EXT_CACHE_GAP ||
++                 cex->ec_type == EXT3_EXT_CACHE_EXTENT);
++      if (block >= cex->ec_block && block < cex->ec_block + cex->ec_len) {
++              ex->ee_block = cex->ec_block;
++              ex->ee_start = cex->ec_start;
++              ex->ee_start_hi = 0;
++              ex->ee_len = cex->ec_len;
++              ext_debug(tree, "%lu cached by %lu:%lu:%lu\n",
++                        (unsigned long) block,
++                        (unsigned long) ex->ee_block,
++                        (unsigned long) ex->ee_len,
++                        (unsigned long) ex->ee_start);
++              return cex->ec_type;
++      }
++
++      /* not in cache */
++      return EXT3_EXT_CACHE_NO;
++}
++
++/*
++ * routine removes index from the index block
++ * it's used in truncate case only. thus all requests are for
++ * last index in the block only
++ */
++int ext3_ext_rm_idx(handle_t *handle, struct ext3_extents_tree *tree,
++                  struct ext3_ext_path *path)
++{
++      struct buffer_head *bh;
++      int err;
++      
++      /* free index block */
++      path--;
++      EXT_ASSERT(path->p_hdr->eh_entries);
++      if ((err = ext3_ext_get_access(handle, tree, path)))
++              return err;
++      path->p_hdr->eh_entries--;
++      if ((err = ext3_ext_dirty(handle, tree, path)))
++              return err;
++      ext_debug(tree, "index is empty, remove it, free block %d\n",
++                path->p_idx->ei_leaf);
++      bh = sb_find_get_block(tree->inode->i_sb, path->p_idx->ei_leaf);
++      ext3_forget(handle, 1, tree->inode, bh, path->p_idx->ei_leaf);
++      ext3_free_blocks(handle, tree->inode, path->p_idx->ei_leaf, 1);
++      return err;
++}
++
++int ext3_ext_calc_credits_for_insert(struct ext3_extents_tree *tree,
++                                   struct ext3_ext_path *path)
++{
++      int depth = EXT_DEPTH(tree);
++      int needed;
++
++      if (path) {
++              /* probably there is space in leaf? */
++              if (path[depth].p_hdr->eh_entries < path[depth].p_hdr->eh_max)
++                      return 1;
++      }
++      
++      /*
++       * the worste case we're expecting is creation of the
++       * new root (growing in depth) with index splitting
++       * for splitting we have to consider depth + 1 because
++       * previous growing could increase it
++       */
++      depth = depth + 1;
++
++      /* 
++       * growing in depth:
++       * block allocation + new root + old root
++       */
++      needed = EXT3_ALLOC_NEEDED + 2;
++
++      /* index split. we may need:
++       *   allocate intermediate indexes and new leaf
++       *   change two blocks at each level, but root
++       *   modify root block (inode)
++       */
++      needed += (depth * EXT3_ALLOC_NEEDED) + (2 * depth) + 1;
++
++      return needed;
++}
++
++static int
++ext3_ext_split_for_rm(handle_t *handle, struct ext3_extents_tree *tree,
++                    struct ext3_ext_path *path, unsigned long start,
++                    unsigned long end)
++{
++      struct ext3_extent *ex, tex;
++      struct ext3_ext_path *npath;
++      int depth, creds, err;
++
++      depth = EXT_DEPTH(tree);
++      ex = path[depth].p_ext;
++      EXT_ASSERT(ex);
++      EXT_ASSERT(end < ex->ee_block + ex->ee_len - 1);
++      EXT_ASSERT(ex->ee_block < start);
++
++      /* calculate tail extent */
++      tex.ee_block = end + 1;
++      EXT_ASSERT(tex.ee_block < ex->ee_block + ex->ee_len);
++      tex.ee_len = ex->ee_block + ex->ee_len - tex.ee_block;
++
++      creds = ext3_ext_calc_credits_for_insert(tree, path);
++      handle = ext3_ext_journal_restart(handle, creds);
++      if (IS_ERR(handle))
++              return PTR_ERR(handle);
++      
++      /* calculate head extent. use primary extent */
++      err = ext3_ext_get_access(handle, tree, path + depth);
++      if (err)
++              return err;
++      ex->ee_len = start - ex->ee_block;
++      err = ext3_ext_dirty(handle, tree, path + depth);
++      if (err)
++              return err;
++
++      /* FIXME: some callback to free underlying resource
++       * and correct ee_start? */
++      ext_debug(tree, "split extent: head %u:%u, tail %u:%u\n",
++                ex->ee_block, ex->ee_len, tex.ee_block, tex.ee_len);
++
++      npath = ext3_ext_find_extent(tree, ex->ee_block, NULL);
++      if (IS_ERR(npath))
++              return PTR_ERR(npath);
++      depth = EXT_DEPTH(tree);
++      EXT_ASSERT(npath[depth].p_ext->ee_block == ex->ee_block);
++      EXT_ASSERT(npath[depth].p_ext->ee_len == ex->ee_len);
++
++      err = ext3_ext_insert_extent(handle, tree, npath, &tex);
++      ext3_ext_drop_refs(npath);
++      kfree(npath);
++
++      return err;
++}
++
++static int
++ext3_ext_rm_leaf(handle_t *handle, struct ext3_extents_tree *tree,
++               struct ext3_ext_path *path, unsigned long start,
++               unsigned long end)
++{
++      struct ext3_extent *ex, *fu = NULL, *lu, *le;
++      int err = 0, correct_index = 0;
++      int depth = EXT_DEPTH(tree), credits;
++      struct ext3_extent_header *eh;
++      unsigned a, b, block, num;
++
++      ext_debug(tree, "remove [%lu:%lu] in leaf\n", start, end);
++      if (!path[depth].p_hdr)
++              path[depth].p_hdr = EXT_BLOCK_HDR(path[depth].p_bh);
++      eh = path[depth].p_hdr;
++      EXT_ASSERT(eh);
++      EXT_ASSERT(eh->eh_entries <= eh->eh_max);
++      EXT_ASSERT(eh->eh_magic == EXT3_EXT_MAGIC);
++      
++      /* find where to start removing */
++      le = ex = EXT_LAST_EXTENT(eh);
++      while (ex != EXT_FIRST_EXTENT(eh)) {
++              if (ex->ee_block <= end)
++                      break;
++              ex--;
++      }
++
++      if (start > ex->ee_block && end < ex->ee_block + ex->ee_len - 1) {
++              /* removal of internal part of the extent requested
++               * tail and head must be placed in different extent
++               * so, we have to insert one more extent */
++              path[depth].p_ext = ex;
++              return ext3_ext_split_for_rm(handle, tree, path, start, end);
++      }
++      
++      lu = ex;
++      while (ex >= EXT_FIRST_EXTENT(eh) && ex->ee_block + ex->ee_len > start) {
++              ext_debug(tree, "remove ext %u:%u\n", ex->ee_block, ex->ee_len);
++              path[depth].p_ext = ex;
++      
++              a = ex->ee_block > start ? ex->ee_block : start;
++              b = ex->ee_block + ex->ee_len - 1 < end ?
++                      ex->ee_block + ex->ee_len - 1 : end;
++              
++              ext_debug(tree, "  border %u:%u\n", a, b);
++
++              if (a != ex->ee_block && b != ex->ee_block + ex->ee_len - 1) {
++                      block = 0;
++                      num = 0;
++                      BUG();
++              } else if (a != ex->ee_block) {
++                      /* remove tail of the extent */
++                      block = ex->ee_block;
++                      num = a - block;
++              } else if (b != ex->ee_block + ex->ee_len - 1) {
++                      /* remove head of the extent */
++                      block = a;
++                      num = b - a;
++              } else {
++                      /* remove whole extent: excelent! */
++                      block = ex->ee_block; 
++                      num = 0;
++                      EXT_ASSERT(a == ex->ee_block &&
++                                 b == ex->ee_block + ex->ee_len - 1);
++              }
++
++              if (ex == EXT_FIRST_EXTENT(eh))
++                      correct_index = 1;
++
++              credits = 1;
++              if (correct_index)
++                      credits += (EXT_DEPTH(tree) * EXT3_ALLOC_NEEDED) + 1;
++              if (tree->ops->remove_extent_credits)
++                      credits+=tree->ops->remove_extent_credits(tree,ex,a,b);
++              
++              handle = ext3_ext_journal_restart(handle, credits);
++              if (IS_ERR(handle)) {
++                      err = PTR_ERR(handle);
++                      goto out;
++              }
++
++              err = ext3_ext_get_access(handle, tree, path + depth);
++              if (err)
++                      goto out;
++
++              if (tree->ops->remove_extent)
++                      err = tree->ops->remove_extent(tree, ex, a, b);
++              if (err)
++                      goto out;
++
++              if (num == 0) {
++                      /* this extent is removed entirely mark slot unused */
++                      ex->ee_start = ex->ee_start_hi = 0;
++                      eh->eh_entries--;
++                      fu = ex;
++              }
++
++              ex->ee_block = block;
++              ex->ee_len = num;
++
++              err = ext3_ext_dirty(handle, tree, path + depth);
++              if (err)
++                      goto out;
++
++              ext_debug(tree, "new extent: %u:%u:%u\n",
++                        ex->ee_block, ex->ee_len, ex->ee_start);
++              ex--;
++      }
++
++      if (fu) {
++              /* reuse unused slots */
++              while (lu < le) {
++                      if (lu->ee_start) {
++                              *fu = *lu;
++                              lu->ee_start = lu->ee_start_hi = 0;
++                              fu++;
++                      }
++                      lu++;
++              }
++      }
++
++      if (correct_index && eh->eh_entries)
++              err = ext3_ext_correct_indexes(handle, tree, path);
++
++      /* if this leaf is free, then we should
++       * remove it from index block above */
++      if (err == 0 && eh->eh_entries == 0 && path[depth].p_bh != NULL)
++              err = ext3_ext_rm_idx(handle, tree, path + depth);
++
++out:
++      return err;
++}
++
++
++static struct ext3_extent_idx *
++ext3_ext_last_covered(struct ext3_extent_header *hdr, unsigned long block)
++{
++      struct ext3_extent_idx *ix;
++      
++      ix = EXT_LAST_INDEX(hdr);
++      while (ix != EXT_FIRST_INDEX(hdr)) {
++              if (ix->ei_block <= block)
++                      break;
++              ix--;
++      }
++      return ix;
++}
++
++/*
++ * returns 1 if current index have to be freed (even partial)
++ */
++static int inline
++ext3_ext_more_to_rm(struct ext3_ext_path *path)
++{
++      EXT_ASSERT(path->p_idx);
++
++      if (path->p_idx < EXT_FIRST_INDEX(path->p_hdr))
++              return 0;
++
++      /*
++       * if truncate on deeper level happened it it wasn't partial
++       * so we have to consider current index for truncation
++       */
++      if (path->p_hdr->eh_entries == path->p_block)
++              return 0;
++      return 1;
++}
++
++int ext3_ext_remove_space(struct ext3_extents_tree *tree,
++                        unsigned long start, unsigned long end)
++{
++      struct inode *inode = tree->inode;
++      struct super_block *sb = inode->i_sb;
++      int depth = EXT_DEPTH(tree);
++      struct ext3_ext_path *path;
++      handle_t *handle;
++      int i = 0, err = 0;
++
++      ext_debug(tree, "space to be removed: %lu:%lu\n", start, end);
++
++      /* probably first extent we're gonna free will be last in block */
++      handle = ext3_journal_start(inode, depth + 1);
++      if (IS_ERR(handle))
++              return PTR_ERR(handle);
++
++      ext3_ext_invalidate_cache(tree);
++
++      /*
++       * we start scanning from right side freeing all the blocks
++       * after i_size and walking into the deep
++       */
++      path = kmalloc(sizeof(struct ext3_ext_path) * (depth + 1), GFP_KERNEL);
++      if (IS_ERR(path)) {
++              ext3_error(sb, __FUNCTION__, "Can't allocate path array");
++              ext3_journal_stop(handle);
++              return -ENOMEM;
++      }
++      memset(path, 0, sizeof(struct ext3_ext_path) * (depth + 1));
++      path[i].p_hdr = EXT_ROOT_HDR(tree);
++      
++      while (i >= 0 && err == 0) {
++              if (i == depth) {
++                      /* this is leaf block */
++                      err = ext3_ext_rm_leaf(handle, tree, path, start, end);
++                      /* root level have p_bh == NULL, brelse() eats this */
++                      brelse(path[i].p_bh);
++                      i--;
++                      continue;
++              }
++              
++              /* this is index block */
++              if (!path[i].p_hdr) {
++                      ext_debug(tree, "initialize header\n");
++                      path[i].p_hdr = EXT_BLOCK_HDR(path[i].p_bh);
++              }
++
++              EXT_ASSERT(path[i].p_hdr->eh_entries <= path[i].p_hdr->eh_max);
++              EXT_ASSERT(path[i].p_hdr->eh_magic == EXT3_EXT_MAGIC);
++              
++              if (!path[i].p_idx) {
++                      /* this level hasn't touched yet */
++                      path[i].p_idx =
++                              ext3_ext_last_covered(path[i].p_hdr, end);
++                      path[i].p_block = path[i].p_hdr->eh_entries + 1;
++                      ext_debug(tree, "init index ptr: hdr 0x%p, num %d\n",
++                                path[i].p_hdr, path[i].p_hdr->eh_entries);
++              } else {
++                      /* we've already was here, see at next index */
++                      path[i].p_idx--;
++              }
++
++              ext_debug(tree, "level %d - index, first 0x%p, cur 0x%p\n",
++                        i, EXT_FIRST_INDEX(path[i].p_hdr),
++                        path[i].p_idx);
++              if (ext3_ext_more_to_rm(path + i)) {
++                      /* go to the next level */
++                      ext_debug(tree, "move to level %d (block %d)\n",
++                                i + 1, path[i].p_idx->ei_leaf);
++                      memset(path + i + 1, 0, sizeof(*path));
++                      path[i+1].p_bh = sb_bread(sb, path[i].p_idx->ei_leaf);
++                      if (!path[i+1].p_bh) {
++                              /* should we reset i_size? */
++                              err = -EIO;
++                              break;
++                      }
++                      /* put actual number of indexes to know is this
++                       * number got changed at the next iteration */
++                      path[i].p_block = path[i].p_hdr->eh_entries;
++                      i++;
++              } else {
++                      /* we finish processing this index, go up */
++                      if (path[i].p_hdr->eh_entries == 0 && i > 0) {
++                              /* index is empty, remove it
++                               * handle must be already prepared by the
++                               * truncatei_leaf() */
++                              err = ext3_ext_rm_idx(handle, tree, path + i);
++                      }
++                      /* root level have p_bh == NULL, brelse() eats this */
++                      brelse(path[i].p_bh);
++                      i--;
++                      ext_debug(tree, "return to level %d\n", i);
++              }
++      }
++
++      /* TODO: flexible tree reduction should be here */
++      if (path->p_hdr->eh_entries == 0) {
++              /*
++               * truncate to zero freed all the tree
++               * so, we need to correct eh_depth
++               */
++              err = ext3_ext_get_access(handle, tree, path);
++              if (err == 0) {
++                      EXT_ROOT_HDR(tree)->eh_depth = 0;
++                      EXT_ROOT_HDR(tree)->eh_max = ext3_ext_space_root(tree);
++                      err = ext3_ext_dirty(handle, tree, path);
++              }
++      }
++      ext3_ext_tree_changed(tree);
++
++      kfree(path);
++      ext3_journal_stop(handle);
++
++      return err;
++}
++
++int ext3_ext_calc_metadata_amount(struct ext3_extents_tree *tree, int blocks)
++{
++      int lcap, icap, rcap, leafs, idxs, num;
++
++      rcap = ext3_ext_space_root(tree);
++      if (blocks <= rcap) {
++              /* all extents fit to the root */
++              return 0;
++      }
++
++      rcap = ext3_ext_space_root_idx(tree);
++      lcap = ext3_ext_space_block(tree);
++      icap = ext3_ext_space_block_idx(tree);
++
++      num = leafs = (blocks + lcap - 1) / lcap;
++      if (leafs <= rcap) {
++              /* all pointers to leafs fit to the root */
++              return leafs;
++      }
++
++      /* ok. we need separate index block(s) to link all leaf blocks */
++      idxs = (leafs + icap - 1) / icap;
++      do {
++              num += idxs;
++              idxs = (idxs + icap - 1) / icap;
++      } while (idxs > rcap);
++
++      return num;
++}
++
++/*
++ * called at mount time
++ */
++void ext3_ext_init(struct super_block *sb)
++{
++      /*
++       * possible initialization would be here
++       */
++
++      if (test_opt(sb, EXTENTS)) {
++              printk("EXT3-fs: file extents enabled");
++#ifdef AGRESSIVE_TEST
++              printk(", agressive tests");
++#endif
++#ifdef CHECK_BINSEARCH
++              printk(", check binsearch");
++#endif
++              printk("\n");
++      }
++}
++
++/*
++ * called at umount time
++ */
++void ext3_ext_release(struct super_block *sb)
++{
++}
++
++/************************************************************************
++ * VFS related routines
++ ************************************************************************/
++
++static int ext3_get_inode_write_access(handle_t *handle, void *buffer)
++{
++      /* we use in-core data, not bh */
++      return 0;
++}
++
++static int ext3_mark_buffer_dirty(handle_t *handle, void *buffer)
++{
++      struct inode *inode = buffer;
++      return ext3_mark_inode_dirty(handle, inode);
++}
++
++static int ext3_ext_mergable(struct ext3_extent *ex1,
++                           struct ext3_extent *ex2)
++{
++      /* FIXME: support for large fs */
++      if (ex1->ee_start + ex1->ee_len == ex2->ee_start)
++              return 1;
++      return 0;
++}
++
++static int
++ext3_remove_blocks_credits(struct ext3_extents_tree *tree,
++                         struct ext3_extent *ex,
++                         unsigned long from, unsigned long to)
++{
++      int needed;
++      
++      /* at present, extent can't cross block group */;
++      needed = 4; /* bitmap + group desc + sb + inode */
++
++#ifdef CONFIG_QUOTA
++      needed += 2 * EXT3_SINGLEDATA_TRANS_BLOCKS;
++#endif
++      return needed;
++}
++
++static int
++ext3_remove_blocks(struct ext3_extents_tree *tree,
++                 struct ext3_extent *ex,
++                 unsigned long from, unsigned long to)
++{
++      int needed = ext3_remove_blocks_credits(tree, ex, from, to);
++      handle_t *handle = ext3_journal_start(tree->inode, needed);
++      struct buffer_head *bh;
++      int i;
++
++      if (IS_ERR(handle))
++              return PTR_ERR(handle);
++      if (from >= ex->ee_block && to == ex->ee_block + ex->ee_len - 1) {
++              /* tail removal */
++              unsigned long num, start;
++              num = ex->ee_block + ex->ee_len - from;
++              start = ex->ee_start + ex->ee_len - num;
++              ext_debug(tree, "free last %lu blocks starting %lu\n",
++                        num, start);
++              for (i = 0; i < num; i++) {
++                      bh = sb_find_get_block(tree->inode->i_sb, start + i);
++                      ext3_forget(handle, 0, tree->inode, bh, start + i);
++              }
++              ext3_free_blocks(handle, tree->inode, start, num);
++      } else if (from == ex->ee_block && to <= ex->ee_block + ex->ee_len - 1) {
++              printk("strange request: removal %lu-%lu from %u:%u\n",
++                     from, to, ex->ee_block, ex->ee_len);
++      } else {
++              printk("strange request: removal(2) %lu-%lu from %u:%u\n",
++                     from, to, ex->ee_block, ex->ee_len);
++      }
++      ext3_journal_stop(handle);
++      return 0;
++}
++
++static int ext3_ext_find_goal(struct inode *inode,
++                            struct ext3_ext_path *path, unsigned long block)
++{
++      struct ext3_inode_info *ei = EXT3_I(inode);
++      unsigned long bg_start;
++      unsigned long colour;
++      int depth;
++      
++      if (path) {
++              struct ext3_extent *ex;
++              depth = path->p_depth;
++              
++              /* try to predict block placement */
++              if ((ex = path[depth].p_ext))
++                      return ex->ee_start + (block - ex->ee_block);
++
++              /* it looks index is empty
++               * try to find starting from index itself */
++              if (path[depth].p_bh)
++                      return path[depth].p_bh->b_blocknr;
++      }
++
++      /* OK. use inode's group */
++      bg_start = (ei->i_block_group * EXT3_BLOCKS_PER_GROUP(inode->i_sb)) +
++              le32_to_cpu(EXT3_SB(inode->i_sb)->s_es->s_first_data_block);
++      colour = (current->pid % 16) *
++                      (EXT3_BLOCKS_PER_GROUP(inode->i_sb) / 16);
++      return bg_start + colour + block;
++}
++
++static int ext3_new_block_cb(handle_t *handle, struct ext3_extents_tree *tree,
++                           struct ext3_ext_path *path,
++                           struct ext3_extent *ex, int *err)
++{
++      struct inode *inode = tree->inode;
++      int newblock, goal;
++      
++      EXT_ASSERT(path);
++      EXT_ASSERT(ex);
++      EXT_ASSERT(ex->ee_start);
++      EXT_ASSERT(ex->ee_len);
++      
++      /* reuse block from the extent to order data/metadata */
++      newblock = ex->ee_start++;
++      ex->ee_len--;
++      if (ex->ee_len == 0) {
++              ex->ee_len = 1;
++              /* allocate new block for the extent */
++              goal = ext3_ext_find_goal(inode, path, ex->ee_block);
++              ex->ee_start = ext3_new_block(handle, inode, goal, err);
++              ex->ee_start_hi = 0;
++              if (ex->ee_start == 0) {
++                      /* error occured: restore old extent */
++                      ex->ee_start = newblock;
++                      return 0;
++              }
++      }
++      return newblock;
++}
++
++static struct ext3_extents_helpers ext3_blockmap_helpers = {
++      .get_write_access       = ext3_get_inode_write_access,
++      .mark_buffer_dirty      = ext3_mark_buffer_dirty,
++      .mergable               = ext3_ext_mergable,
++      .new_block              = ext3_new_block_cb,
++      .remove_extent          = ext3_remove_blocks,
++      .remove_extent_credits  = ext3_remove_blocks_credits,
++};
++
++void ext3_init_tree_desc(struct ext3_extents_tree *tree,
++                       struct inode *inode)
++{
++      tree->inode = inode;
++      tree->root = (void *) EXT3_I(inode)->i_data;
++      tree->buffer = (void *) inode;
++      tree->buffer_len = sizeof(EXT3_I(inode)->i_data);
++      tree->cex = (struct ext3_ext_cache *) &EXT3_I(inode)->i_cached_extent;
++      tree->ops = &ext3_blockmap_helpers;
++}
++
++int ext3_ext_get_block(handle_t *handle, struct inode *inode,
++                     long iblock, struct buffer_head *bh_result,
++                     int create, int extend_disksize)
++{
++      struct ext3_ext_path *path = NULL;
++      struct ext3_extent newex;
++      struct ext3_extent *ex;
++      int goal, newblock, err = 0, depth;
++      struct ext3_extents_tree tree;
++
++      clear_buffer_new(bh_result);
++      ext3_init_tree_desc(&tree, inode);
++      ext_debug(&tree, "block %d requested for inode %u\n",
++                (int) iblock, (unsigned) inode->i_ino);
++      down(&EXT3_I(inode)->truncate_sem);
++
++      /* check in cache */
++      if ((goal = ext3_ext_in_cache(&tree, iblock, &newex))) {
++              if (goal == EXT3_EXT_CACHE_GAP) {
++                      if (!create) {
++                              /* block isn't allocated yet and
++                               * user don't want to allocate it */
++                              goto out2;
++                      }
++                      /* we should allocate requested block */
++              } else if (goal == EXT3_EXT_CACHE_EXTENT) {
++                      /* block is already allocated */
++                      newblock = iblock - newex.ee_block + newex.ee_start;
++                      goto out;
++              } else {
++                      EXT_ASSERT(0);
++              }
++      }
++
++      /* find extent for this block */
++      path = ext3_ext_find_extent(&tree, iblock, NULL);
++      if (IS_ERR(path)) {
++              err = PTR_ERR(path);
++              path = NULL;
++              goto out2;
++      }
++
++      depth = EXT_DEPTH(&tree);
++
++      /*
++       * consistent leaf must not be empty
++       * this situations is possible, though, _during_ tree modification
++       * this is why assert can't be put in ext3_ext_find_extent()
++       */
++      EXT_ASSERT(path[depth].p_ext != NULL || depth == 0);
++
++      if ((ex = path[depth].p_ext)) {
++              /* if found exent covers block, simple return it */
++              if (iblock >= ex->ee_block && iblock < ex->ee_block + ex->ee_len) {
++                      newblock = iblock - ex->ee_block + ex->ee_start;
++                      ext_debug(&tree, "%d fit into %d:%d -> %d\n",
++                                (int) iblock, ex->ee_block, ex->ee_len,
++                                newblock);
++                      ext3_ext_put_in_cache(&tree, ex->ee_block,
++                                            ex->ee_len, ex->ee_start,
++                                            EXT3_EXT_CACHE_EXTENT);
++                      goto out;
++              }
++      }
++
++      /*
++       * requested block isn't allocated yet
++       * we couldn't try to create block if create flag is zero 
++       */
++      if (!create) {
++              /* put just found gap into cache to speedup subsequest reqs */
++              ext3_ext_put_gap_in_cache(&tree, path, iblock);
++              goto out2;
++      }
++
++      /* allocate new block */
++      goal = ext3_ext_find_goal(inode, path, iblock);
++      newblock = ext3_new_block(handle, inode, goal, &err);
++      if (!newblock)
++              goto out2;
++      ext_debug(&tree, "allocate new block: goal %d, found %d\n",
++                goal, newblock);
++
++      /* try to insert new extent into found leaf and return */
++      newex.ee_block = iblock;
++      newex.ee_start = newblock;
++      newex.ee_start_hi = 0;
++      newex.ee_len = 1;
++      err = ext3_ext_insert_extent(handle, &tree, path, &newex);
++      if (err)
++              goto out2;
++      
++      if (extend_disksize && inode->i_size > EXT3_I(inode)->i_disksize)
++              EXT3_I(inode)->i_disksize = inode->i_size;
++
++      /* previous routine could use block we allocated */
++      newblock = newex.ee_start;
++      set_buffer_new(bh_result);
++
++      ext3_ext_put_in_cache(&tree, newex.ee_block, newex.ee_len,
++                            newex.ee_start, EXT3_EXT_CACHE_EXTENT);
++out:
++      ext3_ext_show_leaf(&tree, path);
++      map_bh(bh_result, inode->i_sb, newblock);
++out2:
++      if (path) {
++              ext3_ext_drop_refs(path);
++              kfree(path);
++      }
++      up(&EXT3_I(inode)->truncate_sem);
++
++      return err;     
++}
++
++void ext3_ext_truncate(struct inode * inode, struct page *page)
++{
++      struct address_space *mapping = inode->i_mapping;
++      struct super_block *sb = inode->i_sb;
++      struct ext3_extents_tree tree;
++      unsigned long last_block;
++      handle_t *handle;
++      int err = 0;
++
++      ext3_init_tree_desc(&tree, inode);
++
++      /*
++       * probably first extent we're gonna free will be last in block
++       */
++      err = ext3_writepage_trans_blocks(inode) + 3;
++      handle = ext3_journal_start(inode, err);
++      if (IS_ERR(handle)) {
++              if (page) {
++                      clear_highpage(page);
++                      flush_dcache_page(page);
++                      unlock_page(page);
++                      page_cache_release(page);
++              }
++              return;
++      }
++
++      if (page)
++              ext3_block_truncate_page(handle, page, mapping, inode->i_size);
++
++      down(&EXT3_I(inode)->truncate_sem);
++      ext3_ext_invalidate_cache(&tree);
++
++      /* 
++       * TODO: optimization is possible here
++       * probably we need not scaning at all,
++       * because page truncation is enough
++       */
++      if (ext3_orphan_add(handle, inode))
++              goto out_stop;
++
++      /* we have to know where to truncate from in crash case */
++      EXT3_I(inode)->i_disksize = inode->i_size;
++      ext3_mark_inode_dirty(handle, inode);
++
++      last_block = (inode->i_size + sb->s_blocksize - 1) >>
++                      EXT3_BLOCK_SIZE_BITS(sb);
++      err = ext3_ext_remove_space(&tree, last_block, EXT_MAX_BLOCK);
++      
++      /* In a multi-transaction truncate, we only make the final
++       * transaction synchronous */
++      if (IS_SYNC(inode))
++              handle->h_sync = 1;
++
++out_stop:
++      /*
++       * If this was a simple ftruncate(), and the file will remain alive
++       * then we need to clear up the orphan record which we created above.
++       * However, if this was a real unlink then we were called by
++       * ext3_delete_inode(), and we allow that function to clean up the
++       * orphan info for us.
++       */
++      if (inode->i_nlink)
++              ext3_orphan_del(handle, inode);
++
++      up(&EXT3_I(inode)->truncate_sem);
++      ext3_journal_stop(handle);
++}
++
++/*
++ * this routine calculate max number of blocks we could modify
++ * in order to allocate new block for an inode
++ */
++int ext3_ext_writepage_trans_blocks(struct inode *inode, int num)
++{
++      struct ext3_extents_tree tree;
++      int needed;
++      
++      ext3_init_tree_desc(&tree, inode);
++      
++      needed = ext3_ext_calc_credits_for_insert(&tree, NULL);
++
++      /* caller want to allocate num blocks */
++      needed *= num;
++      
++#ifdef CONFIG_QUOTA
++      /* 
++       * FIXME: real calculation should be here
++       * it depends on blockmap format of qouta file
++       */
++      needed += 2 * EXT3_SINGLEDATA_TRANS_BLOCKS;
++#endif
++
++      return needed;
++}
++
++void ext3_extents_initialize_blockmap(handle_t *handle, struct inode *inode)
++{
++      struct ext3_extents_tree tree;
++
++      ext3_init_tree_desc(&tree, inode);
++      ext3_extent_tree_init(handle, &tree);
++}
++
++int ext3_ext_calc_blockmap_metadata(struct inode *inode, int blocks)
++{
++      struct ext3_extents_tree tree;
++
++      ext3_init_tree_desc(&tree, inode);
++      return ext3_ext_calc_metadata_amount(&tree, blocks);
++}
++      
++static int
++ext3_ext_store_extent_cb(struct ext3_extents_tree *tree,
++                       struct ext3_ext_path *path,
++                       struct ext3_ext_cache *newex)
++{
++      struct ext3_extent_buf *buf = (struct ext3_extent_buf *) tree->private;
++
++      if (newex->ec_type != EXT3_EXT_CACHE_EXTENT)
++              return EXT_CONTINUE;
++
++      if (buf->err < 0)
++              return EXT_BREAK;
++      if (buf->cur - buf->buffer + sizeof(*newex) > buf->buflen)
++              return EXT_BREAK;
++
++      if (!copy_to_user(buf->cur, newex, sizeof(*newex))) {
++              buf->err++;
++              buf->cur += sizeof(*newex);
++      } else {
++              buf->err = -EFAULT;
++              return EXT_BREAK;
++      }
++      return EXT_CONTINUE;
++}
++
++static int
++ext3_ext_collect_stats_cb(struct ext3_extents_tree *tree,
++                        struct ext3_ext_path *path,
++                        struct ext3_ext_cache *ex)
++{
++      struct ext3_extent_tree_stats *buf =
++              (struct ext3_extent_tree_stats *) tree->private;
++      int depth;
++
++      if (ex->ec_type != EXT3_EXT_CACHE_EXTENT)
++              return EXT_CONTINUE;
++
++      depth = EXT_DEPTH(tree);
++      buf->extents_num++;
++      if (path[depth].p_ext == EXT_FIRST_EXTENT(path[depth].p_hdr))
++              buf->leaf_num++;
++      return EXT_CONTINUE;
++}
++
++int ext3_ext_ioctl(struct inode *inode, struct file *filp, unsigned int cmd,
++                 unsigned long arg)
++{
++      int err = 0;
++
++      if (!(EXT3_I(inode)->i_flags & EXT3_EXTENTS_FL))
++              return -EINVAL;
++
++      if (cmd == EXT3_IOC_GET_EXTENTS) {
++              struct ext3_extent_buf buf;
++              struct ext3_extents_tree tree;
++
++              if (copy_from_user(&buf, (void *) arg, sizeof(buf)))
++                      return -EFAULT;
++
++              ext3_init_tree_desc(&tree, inode);
++              buf.cur = buf.buffer;
++              buf.err = 0;
++              tree.private = &buf;
++              down(&EXT3_I(inode)->truncate_sem);
++              err = ext3_ext_walk_space(&tree, buf.start, EXT_MAX_BLOCK,
++                                        ext3_ext_store_extent_cb);
++              up(&EXT3_I(inode)->truncate_sem);
++              if (err == 0)
++                      err = buf.err;
++      } else if (cmd == EXT3_IOC_GET_TREE_STATS) {
++              struct ext3_extent_tree_stats buf;
++              struct ext3_extents_tree tree;
++
++              ext3_init_tree_desc(&tree, inode);
++              down(&EXT3_I(inode)->truncate_sem);
++              buf.depth = EXT_DEPTH(&tree);
++              buf.extents_num = 0;
++              buf.leaf_num = 0;
++              tree.private = &buf;
++              err = ext3_ext_walk_space(&tree, 0, EXT_MAX_BLOCK,
++                                        ext3_ext_collect_stats_cb);
++              up(&EXT3_I(inode)->truncate_sem);
++              if (!err)
++                      err = copy_to_user((void *) arg, &buf, sizeof(buf));
++      } else if (cmd == EXT3_IOC_GET_TREE_DEPTH) {
++              struct ext3_extents_tree tree;
++              ext3_init_tree_desc(&tree, inode);
++              down(&EXT3_I(inode)->truncate_sem);
++              err = EXT_DEPTH(&tree);
++              up(&EXT3_I(inode)->truncate_sem);
++      }
++
++      return err;
++}
++
++EXPORT_SYMBOL(ext3_init_tree_desc);
++EXPORT_SYMBOL(ext3_mark_inode_dirty);
++EXPORT_SYMBOL(ext3_ext_invalidate_cache);
++EXPORT_SYMBOL(ext3_ext_insert_extent);
++EXPORT_SYMBOL(ext3_ext_walk_space);
++EXPORT_SYMBOL(ext3_ext_find_goal);
++EXPORT_SYMBOL(ext3_ext_calc_credits_for_insert);
+Index: linux-2.6.16.27-0.9/fs/ext3/ialloc.c
+===================================================================
+--- linux-2.6.16.27-0.9.orig/fs/ext3/ialloc.c
++++ linux-2.6.16.27-0.9/fs/ext3/ialloc.c
+@@ -601,7 +601,7 @@ got:
+       ei->i_dir_start_lookup = 0;
+       ei->i_disksize = 0;
+-      ei->i_flags = EXT3_I(dir)->i_flags & ~EXT3_INDEX_FL;
++      ei->i_flags = EXT3_I(dir)->i_flags & ~(EXT3_INDEX_FL|EXT3_EXTENTS_FL);
+       if (S_ISLNK(mode))
+               ei->i_flags &= ~(EXT3_IMMUTABLE_FL|EXT3_APPEND_FL);
+       /* dirsync only applies to directories */
+@@ -645,6 +645,18 @@ got:
+       if (err)
+               goto fail_free_drop;
++      if (test_opt(sb, EXTENTS) && S_ISREG(inode->i_mode)) {
++              EXT3_I(inode)->i_flags |= EXT3_EXTENTS_FL;
++              ext3_extents_initialize_blockmap(handle, inode);
++              if (!EXT3_HAS_INCOMPAT_FEATURE(sb, EXT3_FEATURE_INCOMPAT_EXTENTS)) {
++                      err = ext3_journal_get_write_access(handle, EXT3_SB(sb)->s_sbh);
++                      if (err) goto fail;
++                      EXT3_SET_INCOMPAT_FEATURE(sb, EXT3_FEATURE_INCOMPAT_EXTENTS);
++                      BUFFER_TRACE(EXT3_SB(sb)->s_sbh, "call ext3_journal_dirty_metadata");
++                      err = ext3_journal_dirty_metadata(handle, EXT3_SB(sb)->s_sbh);
++              }
++      }
++
+       err = ext3_mark_inode_dirty(handle, inode);
+       if (err) {
+               ext3_std_error(sb, err);
+Index: linux-2.6.16.27-0.9/fs/ext3/inode.c
+===================================================================
+--- linux-2.6.16.27-0.9.orig/fs/ext3/inode.c
++++ linux-2.6.16.27-0.9/fs/ext3/inode.c
+@@ -40,7 +40,7 @@
+ #include "iopen.h"
+ #include "acl.h"
+-static int ext3_writepage_trans_blocks(struct inode *inode);
++int ext3_writepage_trans_blocks(struct inode *inode);
+ /*
+  * Test whether an inode is a fast symlink.
+@@ -788,6 +788,17 @@ out:
+       return err;
+ }
++static inline int
++ext3_get_block_wrap(handle_t *handle, struct inode *inode, long block,
++                  struct buffer_head *bh, int create, int extend_disksize)
++{
++      if (EXT3_I(inode)->i_flags & EXT3_EXTENTS_FL)
++              return ext3_ext_get_block(handle, inode, block, bh, create,
++                                        extend_disksize);
++      return ext3_get_block_handle(handle, inode, block, bh, create,
++                                   extend_disksize);
++}
++
+ static int ext3_get_block(struct inode *inode, sector_t iblock,
+                       struct buffer_head *bh_result, int create)
+ {
+@@ -798,8 +809,8 @@ static int ext3_get_block(struct inode *
+               handle = ext3_journal_current_handle();
+               J_ASSERT(handle != 0);
+       }
+-      ret = ext3_get_block_handle(handle, inode, iblock,
+-                              bh_result, create, 1);
++      ret = ext3_get_block_wrap(handle, inode, iblock,
++                                bh_result, create, 1);
+       return ret;
+ }
+@@ -843,7 +854,7 @@ ext3_direct_io_get_blocks(struct inode *
+ get_block:
+       if (ret == 0)
+-              ret = ext3_get_block_handle(handle, inode, iblock,
++              ret = ext3_get_block_wrap(handle, inode, iblock,
+                                       bh_result, create, 0);
+       bh_result->b_size = (1 << inode->i_blkbits);
+       return ret;
+@@ -863,7 +874,7 @@ struct buffer_head *ext3_getblk(handle_t
+       dummy.b_state = 0;
+       dummy.b_blocknr = -1000;
+       buffer_trace_init(&dummy.b_history);
+-      *errp = ext3_get_block_handle(handle, inode, block, &dummy, create, 1);
++      *errp = ext3_get_block_wrap(handle, inode, block, &dummy, create, 1);
+       if (!*errp && buffer_mapped(&dummy)) {
+               struct buffer_head *bh;
+               bh = sb_getblk(inode->i_sb, dummy.b_blocknr);
+@@ -1606,7 +1617,7 @@ void ext3_set_aops(struct inode *inode)
+  * This required during truncate. We need to physically zero the tail end
+  * of that block so it doesn't yield old data if the file is later grown.
+  */
+-static int ext3_block_truncate_page(handle_t *handle, struct page *page,
++int ext3_block_truncate_page(handle_t *handle, struct page *page,
+               struct address_space *mapping, loff_t from)
+ {
+       unsigned long index = from >> PAGE_CACHE_SHIFT;
+@@ -2116,6 +2127,9 @@ void ext3_truncate(struct inode * inode)
+                       return;
+       }
++      if (EXT3_I(inode)->i_flags & EXT3_EXTENTS_FL)
++              return ext3_ext_truncate(inode, page);
++
+       handle = start_transaction(inode);
+       if (IS_ERR(handle)) {
+               if (page) {
+@@ -2863,12 +2877,15 @@ err_out:
+  * block and work out the exact number of indirects which are touched.  Pah.
+  */
+-static int ext3_writepage_trans_blocks(struct inode *inode)
++int ext3_writepage_trans_blocks(struct inode *inode)
+ {
+       int bpp = ext3_journal_blocks_per_page(inode);
+       int indirects = (EXT3_NDIR_BLOCKS % bpp) ? 5 : 3;
+       int ret;
++      if (EXT3_I(inode)->i_flags & EXT3_EXTENTS_FL)
++              return ext3_ext_writepage_trans_blocks(inode, bpp);
++
+       if (ext3_should_journal_data(inode))
+               ret = 3 * (bpp + indirects) + 2;
+       else
+Index: linux-2.6.16.27-0.9/fs/ext3/Makefile
+===================================================================
+--- linux-2.6.16.27-0.9.orig/fs/ext3/Makefile
++++ linux-2.6.16.27-0.9/fs/ext3/Makefile
+@@ -5,7 +5,8 @@
+ obj-$(CONFIG_EXT3_FS) += ext3.o
+ ext3-y        := balloc.o bitmap.o dir.o file.o fsync.o ialloc.o inode.o iopen.o \
+-         ioctl.o namei.o super.o symlink.o hash.o resize.o
++         ioctl.o namei.o super.o symlink.o hash.o resize.o \
++         extents.o
+ ext3-$(CONFIG_EXT3_FS_XATTR)   += xattr.o xattr_user.o xattr_trusted.o
+ ext3-$(CONFIG_EXT3_FS_POSIX_ACL) += acl.o
+Index: linux-2.6.16.27-0.9/fs/ext3/super.c
+===================================================================
+--- linux-2.6.16.27-0.9.orig/fs/ext3/super.c
++++ linux-2.6.16.27-0.9/fs/ext3/super.c
+@@ -392,6 +392,7 @@ static void ext3_put_super (struct super
+       struct ext3_super_block *es = sbi->s_es;
+       int i;
++      ext3_ext_release(sb);
+       ext3_xattr_put_super(sb);
+       journal_destroy(sbi->s_journal);
+       if (!(sb->s_flags & MS_RDONLY)) {
+@@ -456,6 +457,8 @@ static struct inode *ext3_alloc_inode(st
+ #endif
+       ei->i_block_alloc_info = NULL;
+       ei->vfs_inode.i_version = 1;
++      
++      memset(&ei->i_cached_extent, 0, sizeof(ei->i_cached_extent));
+       return &ei->vfs_inode;
+ }
+@@ -681,6 +684,7 @@ enum {
+       Opt_jqfmt_vfsold, Opt_jqfmt_vfsv0, Opt_quota, Opt_noquota,
+       Opt_ignore, Opt_barrier, Opt_err, Opt_resize, Opt_usrquota,
+       Opt_iopen, Opt_noiopen, Opt_iopen_nopriv,
++      Opt_extents, Opt_noextents, Opt_extdebug,
+       Opt_grpquota
+ };
+@@ -732,6 +736,9 @@ static match_table_t tokens = {
+       {Opt_iopen, "iopen"},
+       {Opt_noiopen, "noiopen"},
+       {Opt_iopen_nopriv, "iopen_nopriv"},
++      {Opt_extents, "extents"},
++      {Opt_noextents, "noextents"},
++      {Opt_extdebug, "extdebug"},
+       {Opt_barrier, "barrier=%u"},
+       {Opt_err, NULL},
+       {Opt_resize, "resize"},
+@@ -1073,6 +1080,15 @@ clear_qf_name:
+               case Opt_nobh:
+                       set_opt(sbi->s_mount_opt, NOBH);
+                       break;
++              case Opt_extents:
++                      set_opt (sbi->s_mount_opt, EXTENTS);
++                      break;
++              case Opt_noextents:
++                      clear_opt (sbi->s_mount_opt, EXTENTS);
++                      break;
++              case Opt_extdebug:
++                      set_opt (sbi->s_mount_opt, EXTDEBUG);
++                      break;
+               default:
+                       printk (KERN_ERR
+                               "EXT3-fs: Unrecognized mount option \"%s\" "
+@@ -1799,6 +1815,7 @@ static int ext3_fill_super (struct super
+       percpu_counter_mod(&sbi->s_dirs_counter,
+               ext3_count_dirs(sb));
++      ext3_ext_init(sb);
+       lock_kernel();
+       return 0;
+Index: linux-2.6.16.27-0.9/fs/ext3/ioctl.c
+===================================================================
+--- linux-2.6.16.27-0.9.orig/fs/ext3/ioctl.c
++++ linux-2.6.16.27-0.9/fs/ext3/ioctl.c
+@@ -125,6 +125,10 @@ flags_err:
+                       err = ext3_change_inode_journal_flag(inode, jflag);
+               return err;
+       }
++      case EXT3_IOC_GET_EXTENTS:
++      case EXT3_IOC_GET_TREE_STATS:
++      case EXT3_IOC_GET_TREE_DEPTH:
++              return ext3_ext_ioctl(inode, filp, cmd, arg);
+       case EXT3_IOC_GETVERSION:
+       case EXT3_IOC_GETVERSION_OLD:
+               return put_user(inode->i_generation, (int __user *) arg);
+Index: linux-2.6.16.27-0.9/include/linux/ext3_fs.h
+===================================================================
+--- linux-2.6.16.27-0.9.orig/include/linux/ext3_fs.h
++++ linux-2.6.16.27-0.9/include/linux/ext3_fs.h
+@@ -185,9 +185,10 @@ struct ext3_group_desc
+ #define EXT3_NOTAIL_FL                        0x00008000 /* file tail should not be merged */
+ #define EXT3_DIRSYNC_FL                       0x00010000 /* dirsync behaviour (directories only) */
+ #define EXT3_TOPDIR_FL                        0x00020000 /* Top of directory hierarchies*/
++#define EXT3_EXTENTS_FL                       0x00080000 /* Inode uses extents */
+ #define EXT3_RESERVED_FL              0x80000000 /* reserved for ext3 lib */
+-#define EXT3_FL_USER_VISIBLE          0x0003DFFF /* User visible flags */
++#define EXT3_FL_USER_VISIBLE          0x000BDFFF /* User visible flags */
+ #define EXT3_FL_USER_MODIFIABLE               0x000380FF /* User modifiable flags */
+ /*
+@@ -237,6 +238,9 @@ struct ext3_new_group_data {
+ #endif
+ #define EXT3_IOC_GETRSVSZ             _IOR('f', 5, long)
+ #define EXT3_IOC_SETRSVSZ             _IOW('f', 6, long)
++#define EXT3_IOC_GET_EXTENTS          _IOR('f', 7, long)
++#define EXT3_IOC_GET_TREE_DEPTH               _IOR('f', 8, long)
++#define EXT3_IOC_GET_TREE_STATS               _IOR('f', 9, long)
+ /*
+  *  Mount options
+@@ -377,6 +381,8 @@ struct ext3_inode {
+ #define EXT3_MOUNT_GRPQUOTA           0x200000 /* "old" group quota */
+ #define EXT3_MOUNT_IOPEN              0x400000        /* Allow access via iopen */
+ #define EXT3_MOUNT_IOPEN_NOPRIV               0x800000/* Make iopen world-readable */
++#define EXT3_MOUNT_EXTENTS            0x1000000/* Extents support */
++#define EXT3_MOUNT_EXTDEBUG           0x2000000/* Extents debug */
+ /* Compatibility, for having both ext2_fs.h and ext3_fs.h included at once */
+ #ifndef clear_opt
+@@ -565,11 +571,13 @@ static inline struct ext3_inode_info *EX
+ #define EXT3_FEATURE_INCOMPAT_RECOVER         0x0004 /* Needs recovery */
+ #define EXT3_FEATURE_INCOMPAT_JOURNAL_DEV     0x0008 /* Journal device */
+ #define EXT3_FEATURE_INCOMPAT_META_BG         0x0010
++#define EXT3_FEATURE_INCOMPAT_EXTENTS         0x0040 /* extents support */
+ #define EXT3_FEATURE_COMPAT_SUPP      EXT2_FEATURE_COMPAT_EXT_ATTR
+ #define EXT3_FEATURE_INCOMPAT_SUPP    (EXT3_FEATURE_INCOMPAT_FILETYPE| \
+                                        EXT3_FEATURE_INCOMPAT_RECOVER| \
+-                                       EXT3_FEATURE_INCOMPAT_META_BG)
++                                       EXT3_FEATURE_INCOMPAT_META_BG| \
++                                       EXT3_FEATURE_INCOMPAT_EXTENTS)
+ #define EXT3_FEATURE_RO_COMPAT_SUPP   (EXT3_FEATURE_RO_COMPAT_SPARSE_SUPER| \
+                                        EXT3_FEATURE_RO_COMPAT_LARGE_FILE| \
+                                        EXT3_FEATURE_RO_COMPAT_BTREE_DIR)
+@@ -776,6 +784,7 @@ extern unsigned long ext3_count_free (st
+ /* inode.c */
++extern int ext3_block_truncate_page(handle_t *, struct page *, struct address_space *, loff_t);
+ int ext3_forget(handle_t *, int, struct inode *, struct buffer_head *, int);
+ struct buffer_head * ext3_getblk (handle_t *, struct inode *, long, int, int *);
+ struct buffer_head * ext3_bread (handle_t *, struct inode *, int, int, int *);
+@@ -795,6 +804,7 @@ extern int ext3_get_inode_loc(struct ino
+ extern void ext3_truncate (struct inode *);
+ extern void ext3_set_inode_flags(struct inode *);
+ extern void ext3_set_aops(struct inode *inode);
++extern int ext3_writepage_trans_blocks(struct inode *inode);
+ /* ioctl.c */
+ extern int ext3_ioctl (struct inode *, struct file *, unsigned int,
+@@ -848,6 +858,16 @@ extern struct inode_operations ext3_spec
+ extern struct inode_operations ext3_symlink_inode_operations;
+ extern struct inode_operations ext3_fast_symlink_inode_operations;
++/* extents.c */
++extern int ext3_ext_writepage_trans_blocks(struct inode *, int);
++extern int ext3_ext_get_block(handle_t *, struct inode *, long,
++                            struct buffer_head *, int, int);
++extern void ext3_ext_truncate(struct inode *, struct page *);
++extern void ext3_ext_init(struct super_block *);
++extern void ext3_ext_release(struct super_block *);
++extern void ext3_extents_initialize_blockmap(handle_t *, struct inode *);
++extern int ext3_ext_ioctl(struct inode *inode, struct file *filp,
++                        unsigned int cmd, unsigned long arg);
+ #endif        /* __KERNEL__ */
+Index: linux-2.6.16.27-0.9/include/linux/ext3_extents.h
+===================================================================
+--- /dev/null
++++ linux-2.6.16.27-0.9/include/linux/ext3_extents.h
+@@ -0,0 +1,262 @@
++/*
++ * Copyright (c) 2003, Cluster File Systems, Inc, info@clusterfs.com
++ * Written by Alex Tomas <alex@clusterfs.com>
++ *
++ * This program is free software; you can redistribute it and/or modify
++ * it under the terms of the GNU General Public License version 2 as
++ * published by the Free Software Foundation.
++ *
++ * This program is distributed in the hope that it will be useful,
++ * but WITHOUT ANY WARRANTY; without even the implied warranty of
++ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
++ * GNU General Public License for more details.
++ *
++ * You should have received a copy of the GNU General Public Licens
++ * along with this program; if not, write to the Free Software
++ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-
++ */
++
++#ifndef _LINUX_EXT3_EXTENTS
++#define _LINUX_EXT3_EXTENTS
++
++/*
++ * with AGRESSIVE_TEST defined capacity of index/leaf blocks
++ * become very little, so index split, in-depth growing and
++ * other hard changes happens much more often
++ * this is for debug purposes only
++ */
++#define AGRESSIVE_TEST_
++
++/*
++ * if CHECK_BINSEARCH defined, then results of binary search
++ * will be checked by linear search
++ */
++#define CHECK_BINSEARCH_
++
++/*
++ * if EXT_DEBUG is defined you can use 'extdebug' mount option
++ * to get lots of info what's going on
++ */
++#define EXT_DEBUG_
++#ifdef EXT_DEBUG
++#define ext_debug(tree,fmt,a...)                      \
++do {                                                  \
++      if (test_opt((tree)->inode->i_sb, EXTDEBUG))    \
++              printk(fmt, ##a);                       \
++} while (0);
++#else
++#define ext_debug(tree,fmt,a...)
++#endif
++
++/*
++ * if EXT_STATS is defined then stats numbers are collected
++ * these number will be displayed at umount time
++ */
++#define EXT_STATS_
++
++
++#define EXT3_ALLOC_NEEDED     3       /* block bitmap + group desc. + sb */
++
++/*
++ * ext3_inode has i_block array (total 60 bytes)
++ * first 4 bytes are used to store:
++ *  - tree depth (0 mean there is no tree yet. all extents in the inode)
++ *  - number of alive extents in the inode
++ */
++
++/*
++ * this is extent on-disk structure
++ * it's used at the bottom of the tree
++ */
++struct ext3_extent {
++      __u32   ee_block;       /* first logical block extent covers */
++      __u16   ee_len;         /* number of blocks covered by extent */
++      __u16   ee_start_hi;    /* high 16 bits of physical block */
++      __u32   ee_start;       /* low 32 bigs of physical block */
++};
++
++/*
++ * this is index on-disk structure
++ * it's used at all the levels, but the bottom
++ */
++struct ext3_extent_idx {
++      __u32   ei_block;       /* index covers logical blocks from 'block' */
++      __u32   ei_leaf;        /* pointer to the physical block of the next *
++                               * level. leaf or next index could bet here */
++      __u16   ei_leaf_hi;     /* high 16 bits of physical block */
++      __u16   ei_unused;
++};
++
++/*
++ * each block (leaves and indexes), even inode-stored has header
++ */
++struct ext3_extent_header {   
++      __u16   eh_magic;       /* probably will support different formats */   
++      __u16   eh_entries;     /* number of valid entries */
++      __u16   eh_max;         /* capacity of store in entries */
++      __u16   eh_depth;       /* has tree real underlaying blocks? */
++      __u32   eh_generation;  /* flags(8 bits) | generation of the tree */
++};
++
++#define EXT3_EXT_MAGIC                0xf30a
++
++/*
++ * array of ext3_ext_path contains path to some extent
++ * creation/lookup routines use it for traversal/splitting/etc
++ * truncate uses it to simulate recursive walking
++ */
++struct ext3_ext_path {
++      __u32                           p_block;
++      __u16                           p_depth;
++      struct ext3_extent              *p_ext;
++      struct ext3_extent_idx          *p_idx;
++      struct ext3_extent_header       *p_hdr;
++      struct buffer_head              *p_bh;
++};
++
++/*
++ * structure for external API
++ */
++
++/*
++ * storage for cached extent
++ */
++struct ext3_ext_cache {
++      __u32   ec_start;
++      __u32   ec_block;
++      __u32   ec_len;
++      __u32   ec_type;
++};
++
++#define EXT3_EXT_CACHE_NO     0
++#define EXT3_EXT_CACHE_GAP    1
++#define EXT3_EXT_CACHE_EXTENT 2
++
++/*
++ * ext3_extents_tree is used to pass initial information
++ * to top-level extents API
++ */
++struct ext3_extents_helpers;
++struct ext3_extents_tree {
++      struct inode *inode;    /* inode which tree belongs to */
++      void *root;             /* ptr to data top of tree resides at */
++      void *buffer;           /* will be passed as arg to ^^ routines */
++      int buffer_len;
++      void *private;
++      struct ext3_ext_cache *cex;/* last found extent */
++      struct ext3_extents_helpers *ops;
++};
++
++struct ext3_extents_helpers {
++      int (*get_write_access)(handle_t *h, void *buffer);
++      int (*mark_buffer_dirty)(handle_t *h, void *buffer);
++      int (*mergable)(struct ext3_extent *ex1, struct ext3_extent *ex2);
++      int (*remove_extent_credits)(struct ext3_extents_tree *,
++                                   struct ext3_extent *, unsigned long,
++                                   unsigned long);
++      int (*remove_extent)(struct ext3_extents_tree *,
++                           struct ext3_extent *, unsigned long,
++                           unsigned long);
++      int (*new_block)(handle_t *, struct ext3_extents_tree *,
++                       struct ext3_ext_path *, struct ext3_extent *,
++                       int *);
++};
++
++/*
++ * to be called by ext3_ext_walk_space()
++ * negative retcode - error
++ * positive retcode - signal for ext3_ext_walk_space(), see below
++ * callback must return valid extent (passed or newly created)
++ */
++typedef int (*ext_prepare_callback)(struct ext3_extents_tree *,
++                                  struct ext3_ext_path *,
++                                  struct ext3_ext_cache *);
++
++#define EXT_CONTINUE  0
++#define EXT_BREAK     1
++#define EXT_REPEAT    2
++
++
++#define EXT_MAX_BLOCK 0xffffffff
++
++
++#define EXT_FIRST_EXTENT(__hdr__) \
++      ((struct ext3_extent *) (((char *) (__hdr__)) +         \
++                               sizeof(struct ext3_extent_header)))
++#define EXT_FIRST_INDEX(__hdr__) \
++      ((struct ext3_extent_idx *) (((char *) (__hdr__)) +     \
++                                   sizeof(struct ext3_extent_header)))
++#define EXT_HAS_FREE_INDEX(__path__) \
++      ((__path__)->p_hdr->eh_entries < (__path__)->p_hdr->eh_max)
++#define EXT_LAST_EXTENT(__hdr__) \
++      (EXT_FIRST_EXTENT((__hdr__)) + (__hdr__)->eh_entries - 1)
++#define EXT_LAST_INDEX(__hdr__) \
++      (EXT_FIRST_INDEX((__hdr__)) + (__hdr__)->eh_entries - 1)
++#define EXT_MAX_EXTENT(__hdr__) \
++      (EXT_FIRST_EXTENT((__hdr__)) + (__hdr__)->eh_max - 1)
++#define EXT_MAX_INDEX(__hdr__) \
++      (EXT_FIRST_INDEX((__hdr__)) + (__hdr__)->eh_max - 1)
++#define EXT_HDR_GEN(__hdr__)  ((__hdr__)->eh_generation & 0x00ffffff)
++#define EXT_FLAGS(__hdr__)    ((__hdr__)->eh_generation >> 24)
++#define EXT_FLAGS_CLR_UNKNOWN 0x7     /* Flags cleared on modification */
++
++#define EXT_BLOCK_HDR(__bh__)         ((struct ext3_extent_header *)(__bh__)->b_data)
++#define EXT_ROOT_HDR(__tree__)        ((struct ext3_extent_header *)(__tree__)->root)
++#define EXT_DEPTH(__tree__)   (EXT_ROOT_HDR(__tree__)->eh_depth)
++#define EXT_GENERATION(__tree__) EXT_HDR_GEN(EXT_ROOT_HDR(__tree__))
++
++#define EXT_ASSERT(__x__) if (!(__x__)) BUG();
++
++#define EXT_CHECK_PATH(tree,path)                                     \
++{                                                                     \
++      int depth = EXT_DEPTH(tree);                                    \
++      BUG_ON((unsigned long) (path) < __PAGE_OFFSET);                 \
++      BUG_ON((unsigned long) (path)[depth].p_idx <                    \
++                      __PAGE_OFFSET && (path)[depth].p_idx != NULL);  \
++      BUG_ON((unsigned long) (path)[depth].p_ext <                    \
++                      __PAGE_OFFSET && (path)[depth].p_ext != NULL);  \
++      BUG_ON((unsigned long) (path)[depth].p_hdr < __PAGE_OFFSET);    \
++      BUG_ON((unsigned long) (path)[depth].p_bh < __PAGE_OFFSET       \
++                      && depth != 0);                                 \
++      BUG_ON((path)[0].p_depth != depth);                             \
++}
++
++
++/*
++ * this structure is used to gather extents from the tree via ioctl
++ */
++struct ext3_extent_buf {
++      unsigned long start;
++      int buflen;
++      void *buffer;
++      void *cur;
++      int err;
++};
++
++/*
++ * this structure is used to collect stats info about the tree
++ */
++struct ext3_extent_tree_stats {
++      int depth;
++      int extents_num;
++      int leaf_num;
++};
++
++extern void ext3_init_tree_desc(struct ext3_extents_tree *, struct inode *);
++extern int ext3_extent_tree_init(handle_t *, struct ext3_extents_tree *);
++extern int ext3_ext_calc_credits_for_insert(struct ext3_extents_tree *, struct ext3_ext_path *);
++extern int ext3_ext_insert_extent(handle_t *, struct ext3_extents_tree *, struct ext3_ext_path *, struct ext3_extent *);
++extern int ext3_ext_walk_space(struct ext3_extents_tree *, unsigned long, unsigned long, ext_prepare_callback);
++extern int ext3_ext_remove_space(struct ext3_extents_tree *, unsigned long, unsigned long);
++extern struct ext3_ext_path * ext3_ext_find_extent(struct ext3_extents_tree *, int, struct ext3_ext_path *);
++extern int ext3_ext_calc_blockmap_metadata(struct inode *, int);
++
++static inline void
++ext3_ext_invalidate_cache(struct ext3_extents_tree *tree)
++{
++      if (tree->cex)
++              tree->cex->ec_type = EXT3_EXT_CACHE_NO;
++}
++
++
++#endif /* _LINUX_EXT3_EXTENTS */
+Index: linux-2.6.16.27-0.9/include/linux/ext3_fs_i.h
+===================================================================
+--- linux-2.6.16.27-0.9.orig/include/linux/ext3_fs_i.h
++++ linux-2.6.16.27-0.9/include/linux/ext3_fs_i.h
+@@ -133,6 +133,8 @@ struct ext3_inode_info {
+        */
+       struct semaphore truncate_sem;
+       struct inode vfs_inode;
++
++      __u32 i_cached_extent[4];
+ };
+ #endif        /* _LINUX_EXT3_FS_I */
index bfba5fb..18a2997 100644 (file)
@@ -4,7 +4,7 @@ iopen-2.6-fc5.patch
 ext3-map_inode_page-2.6-suse.patch
 export-ext3-2.6-rhel4.patch
 ext3-include-fixes-2.6-rhel4.patch
-ext3-extents-2.6.15.patch
+ext3-extents-2.6.16-sles10.patch
 ext3-mballoc2-2.6-fc5.patch
 ext3-nlinks-2.6.9.patch
 ext3-ialloc-2.6.patch