Linux-2.6.12-rc2v2.6.12-rc2

Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.

Let it rip!

1 files changed, 2073 insertions, 0 deletions

diff --git a/fs/reiserfs/stree.c b/fs/reiserfs/stree.c
new file mode 100644
index 000000000000..73ec5212178b
--- /dev/null
+++ b/fs/reiserfs/stree.c
@@ -0,0 +1,2073 @@
+/*
+ *  Copyright 2000 by Hans Reiser, licensing governed by reiserfs/README
+ */
+
+/*
+ *  Written by Anatoly P. Pinchuk pap@namesys.botik.ru
+ *  Programm System Institute
+ *  Pereslavl-Zalessky Russia
+ */
+
+/*
+ *  This file contains functions dealing with S+tree
+ *
+ * B_IS_IN_TREE
+ * copy_item_head
+ * comp_short_keys
+ * comp_keys
+ * comp_short_le_keys
+ * le_key2cpu_key
+ * comp_le_keys
+ * bin_search
+ * get_lkey
+ * get_rkey
+ * key_in_buffer
+ * decrement_bcount
+ * decrement_counters_in_path
+ * reiserfs_check_path
+ * pathrelse_and_restore
+ * pathrelse
+ * search_by_key_reada
+ * search_by_key
+ * search_for_position_by_key
+ * comp_items
+ * prepare_for_direct_item
+ * prepare_for_direntry_item
+ * prepare_for_delete_or_cut
+ * calc_deleted_bytes_number
+ * init_tb_struct
+ * padd_item
+ * reiserfs_delete_item
+ * reiserfs_delete_solid_item
+ * reiserfs_delete_object
+ * maybe_indirect_to_direct
+ * indirect_to_direct_roll_back
+ * reiserfs_cut_from_item
+ * truncate_directory
+ * reiserfs_do_truncate
+ * reiserfs_paste_into_item
+ * reiserfs_insert_item
+ */
+
+#include <linux/config.h>
+#include <linux/time.h>
+#include <linux/string.h>
+#include <linux/pagemap.h>
+#include <linux/reiserfs_fs.h>
+#include <linux/smp_lock.h>
+#include <linux/buffer_head.h>
+#include <linux/quotaops.h>
+
+/* Does the buffer contain a disk block which is in the tree. */
+inline int B_IS_IN_TREE (const struct buffer_head * p_s_bh)
+{
+
+  RFALSE( B_LEVEL (p_s_bh) > MAX_HEIGHT,
+          "PAP-1010: block (%b) has too big level (%z)", p_s_bh, p_s_bh);
+
+  return ( B_LEVEL (p_s_bh) != FREE_LEVEL );
+}
+
+//
+// to gets item head in le form
+//
+inline void copy_item_head(struct item_head * p_v_to, 
+                           const struct item_head * p_v_from)
+{
+  memcpy (p_v_to, p_v_from, IH_SIZE);
+}
+
+
+/* k1 is pointer to on-disk structure which is stored in little-endian
+   form. k2 is pointer to cpu variable. For key of items of the same
+   object this returns 0.
+   Returns: -1 if key1 < key2 
+   0 if key1 == key2
+   1 if key1 > key2 */
+inline int  comp_short_keys (const struct reiserfs_key * le_key,
+                             const struct cpu_key * cpu_key)
+{
+  __u32 * p_s_le_u32, * p_s_cpu_u32;
+  int n_key_length = REISERFS_SHORT_KEY_LEN;
+
+  p_s_le_u32 = (__u32 *)le_key;
+  p_s_cpu_u32 = (__u32 *)&cpu_key->on_disk_key;
+  for( ; n_key_length--; ++p_s_le_u32, ++p_s_cpu_u32 ) {
+    if ( le32_to_cpu (*p_s_le_u32) < *p_s_cpu_u32 )
+      return -1;
+    if ( le32_to_cpu (*p_s_le_u32) > *p_s_cpu_u32 )
+      return 1;
+  }
+
+  return 0;
+}
+
+
+/* k1 is pointer to on-disk structure which is stored in little-endian
+   form. k2 is pointer to cpu variable.
+   Compare keys using all 4 key fields.
+   Returns: -1 if key1 < key2 0
+   if key1 = key2 1 if key1 > key2 */
+static inline int  comp_keys (const struct reiserfs_key * le_key, const struct cpu_key * cpu_key)
+{
+  int retval;
+
+  retval = comp_short_keys (le_key, cpu_key);
+  if (retval)
+      return retval;
+  if (le_key_k_offset (le_key_version(le_key), le_key) < cpu_key_k_offset (cpu_key))
+      return -1;
+  if (le_key_k_offset (le_key_version(le_key), le_key) > cpu_key_k_offset (cpu_key))
+      return 1;
+
+  if (cpu_key->key_length == 3)
+      return 0;
+
+  /* this part is needed only when tail conversion is in progress */
+  if (le_key_k_type (le_key_version(le_key), le_key) < cpu_key_k_type (cpu_key))
+    return -1;
+
+  if (le_key_k_type (le_key_version(le_key), le_key) > cpu_key_k_type (cpu_key))
+    return 1;
+
+  return 0;
+}
+
+
+inline int comp_short_le_keys (const struct reiserfs_key * key1, const struct reiserfs_key * key2)
+{
+  __u32 * p_s_1_u32, * p_s_2_u32;
+  int n_key_length = REISERFS_SHORT_KEY_LEN;
+
+  p_s_1_u32 = (__u32 *)key1;
+  p_s_2_u32 = (__u32 *)key2;
+  for( ; n_key_length--; ++p_s_1_u32, ++p_s_2_u32 ) {
+    if ( le32_to_cpu (*p_s_1_u32) < le32_to_cpu (*p_s_2_u32) )
+      return -1;
+    if ( le32_to_cpu (*p_s_1_u32) > le32_to_cpu (*p_s_2_u32) )
+      return 1;
+  }
+  return 0;
+}
+
+inline void le_key2cpu_key (struct cpu_key * to, const struct reiserfs_key * from)
+{
+    to->on_disk_key.k_dir_id = le32_to_cpu (from->k_dir_id);
+    to->on_disk_key.k_objectid = le32_to_cpu (from->k_objectid);
+    
+    // find out version of the key
+    to->version = le_key_version (from);
+    if (to->version == KEY_FORMAT_3_5) {
+        to->on_disk_key.u.k_offset_v1.k_offset = le32_to_cpu (from->u.k_offset_v1.k_offset);
+        to->on_disk_key.u.k_offset_v1.k_uniqueness = le32_to_cpu (from->u.k_offset_v1.k_uniqueness);
+    } else {
+        to->on_disk_key.u.k_offset_v2.k_offset = offset_v2_k_offset(&from->u.k_offset_v2);
+        to->on_disk_key.u.k_offset_v2.k_type = offset_v2_k_type(&from->u.k_offset_v2);
+    } 
+}
+
+
+
+// this does not say which one is bigger, it only returns 1 if keys
+// are not equal, 0 otherwise
+inline int comp_le_keys (const struct reiserfs_key * k1, const struct reiserfs_key * k2)
+{
+    return memcmp (k1, k2, sizeof (struct reiserfs_key));
+}
+
+/**************************************************************************
+ *  Binary search toolkit function                                        *
+ *  Search for an item in the array by the item key                       *
+ *  Returns:    1 if found,  0 if not found;                              *
+ *        *p_n_pos = number of the searched element if found, else the    *
+ *        number of the first element that is larger than p_v_key.        *
+ **************************************************************************/
+/* For those not familiar with binary search: n_lbound is the leftmost item that it
+ could be, n_rbound the rightmost item that it could be.  We examine the item
+ halfway between n_lbound and n_rbound, and that tells us either that we can increase
+ n_lbound, or decrease n_rbound, or that we have found it, or if n_lbound <= n_rbound that
+ there are no possible items, and we have not found it. With each examination we
+ cut the number of possible items it could be by one more than half rounded down,
+ or we find it. */
+static inline   int bin_search (
+              const void * p_v_key, /* Key to search for.                   */
+              const void * p_v_base,/* First item in the array.             */
+              int       p_n_num,    /* Number of items in the array.        */
+              int       p_n_width,  /* Item size in the array.
+                                       searched. Lest the reader be
+                                       confused, note that this is crafted
+                                       as a general function, and when it
+                                       is applied specifically to the array
+                                       of item headers in a node, p_n_width
+                                       is actually the item header size not
+                                       the item size.                      */
+              int     * p_n_pos     /* Number of the searched for element. */
+            ) {
+    int   n_rbound, n_lbound, n_j;
+
+   for ( n_j = ((n_rbound = p_n_num - 1) + (n_lbound = 0))/2; n_lbound <= n_rbound; n_j = (n_rbound + n_lbound)/2 )
+     switch( comp_keys((struct reiserfs_key *)((char * )p_v_base + n_j * p_n_width), (struct cpu_key *)p_v_key) )  {
+     case -1: n_lbound = n_j + 1; continue;
+     case  1: n_rbound = n_j - 1; continue;
+     case  0: *p_n_pos = n_j;     return ITEM_FOUND; /* Key found in the array.  */
+        }
+
+    /* bin_search did not find given key, it returns position of key,
+        that is minimal and greater than the given one. */
+    *p_n_pos = n_lbound;
+    return ITEM_NOT_FOUND;
+}
+
+#ifdef CONFIG_REISERFS_CHECK
+extern struct tree_balance * cur_tb;
+#endif
+
+
+
+/* Minimal possible key. It is never in the tree. */
+const struct reiserfs_key  MIN_KEY = {0, 0, {{0, 0},}};
+
+/* Maximal possible key. It is never in the tree. */
+const struct reiserfs_key  MAX_KEY = {0xffffffff, 0xffffffff, {{0xffffffff, 0xffffffff},}};
+
+
+/* Get delimiting key of the buffer by looking for it in the buffers in the path, starting from the bottom
+   of the path, and going upwards.  We must check the path's validity at each step.  If the key is not in
+   the path, there is no delimiting key in the tree (buffer is first or last buffer in tree), and in this
+   case we return a special key, either MIN_KEY or MAX_KEY. */
+static inline   const struct  reiserfs_key * get_lkey  (
+                        const struct path         * p_s_chk_path,
+                        const struct super_block  * p_s_sb
+                      ) {
+  int                   n_position, n_path_offset = p_s_chk_path->path_length;
+  struct buffer_head  * p_s_parent;
+  
+  RFALSE( n_path_offset < FIRST_PATH_ELEMENT_OFFSET, 
+          "PAP-5010: invalid offset in the path");
+
+  /* While not higher in path than first element. */
+  while ( n_path_offset-- > FIRST_PATH_ELEMENT_OFFSET ) {
+
+    RFALSE( ! buffer_uptodate(PATH_OFFSET_PBUFFER(p_s_chk_path, n_path_offset)),
+            "PAP-5020: parent is not uptodate");
+
+    /* Parent at the path is not in the tree now. */
+    if ( ! B_IS_IN_TREE(p_s_parent = PATH_OFFSET_PBUFFER(p_s_chk_path, n_path_offset)) )
+      return &MAX_KEY;
+    /* Check whether position in the parent is correct. */
+    if ( (n_position = PATH_OFFSET_POSITION(p_s_chk_path, n_path_offset)) > B_NR_ITEMS(p_s_parent) )
+       return &MAX_KEY;
+    /* Check whether parent at the path really points to the child. */
+    if ( B_N_CHILD_NUM(p_s_parent, n_position) !=
+         PATH_OFFSET_PBUFFER(p_s_chk_path, n_path_offset + 1)->b_blocknr )
+      return &MAX_KEY;
+    /* Return delimiting key if position in the parent is not equal to zero. */
+    if ( n_position )
+      return B_N_PDELIM_KEY(p_s_parent, n_position - 1);
+  }
+  /* Return MIN_KEY if we are in the root of the buffer tree. */
+  if ( PATH_OFFSET_PBUFFER(p_s_chk_path, FIRST_PATH_ELEMENT_OFFSET)->b_blocknr ==
+       SB_ROOT_BLOCK (p_s_sb) )
+    return &MIN_KEY;
+  return  &MAX_KEY;
+}
+
+
+/* Get delimiting key of the buffer at the path and its right neighbor. */
+inline  const struct  reiserfs_key * get_rkey  (
+                        const struct path         * p_s_chk_path,
+                        const struct super_block  * p_s_sb
+                      ) {
+  int                   n_position,
+                        n_path_offset = p_s_chk_path->path_length;
+  struct buffer_head  * p_s_parent;
+
+  RFALSE( n_path_offset < FIRST_PATH_ELEMENT_OFFSET,
+          "PAP-5030: invalid offset in the path");
+
+  while ( n_path_offset-- > FIRST_PATH_ELEMENT_OFFSET ) {
+
+    RFALSE( ! buffer_uptodate(PATH_OFFSET_PBUFFER(p_s_chk_path, n_path_offset)),
+            "PAP-5040: parent is not uptodate");
+
+    /* Parent at the path is not in the tree now. */
+    if ( ! B_IS_IN_TREE(p_s_parent = PATH_OFFSET_PBUFFER(p_s_chk_path, n_path_offset)) )
+      return &MIN_KEY;
+    /* Check whether position in the parent is correct. */
+    if ( (n_position = PATH_OFFSET_POSITION(p_s_chk_path, n_path_offset)) > B_NR_ITEMS(p_s_parent) )
+      return &MIN_KEY;
+    /* Check whether parent at the path really points to the child. */
+    if ( B_N_CHILD_NUM(p_s_parent, n_position) !=
+                                        PATH_OFFSET_PBUFFER(p_s_chk_path, n_path_offset + 1)->b_blocknr )
+      return &MIN_KEY;
+    /* Return delimiting key if position in the parent is not the last one. */
+    if ( n_position != B_NR_ITEMS(p_s_parent) )
+      return B_N_PDELIM_KEY(p_s_parent, n_position);
+  }
+  /* Return MAX_KEY if we are in the root of the buffer tree. */
+  if ( PATH_OFFSET_PBUFFER(p_s_chk_path, FIRST_PATH_ELEMENT_OFFSET)->b_blocknr ==
+       SB_ROOT_BLOCK (p_s_sb) )
+    return &MAX_KEY;
+  return  &MIN_KEY;
+}
+
+
+/* Check whether a key is contained in the tree rooted from a buffer at a path. */
+/* This works by looking at the left and right delimiting keys for the buffer in the last path_element in
+   the path.  These delimiting keys are stored at least one level above that buffer in the tree. If the
+   buffer is the first or last node in the tree order then one of the delimiting keys may be absent, and in
+   this case get_lkey and get_rkey return a special key which is MIN_KEY or MAX_KEY. */
+static  inline  int key_in_buffer (
+                      struct path         * p_s_chk_path, /* Path which should be checked.  */
+                      const struct cpu_key      * p_s_key,      /* Key which should be checked.   */
+                      struct super_block  * p_s_sb        /* Super block pointer.           */
+                      ) {
+
+  RFALSE( ! p_s_key || p_s_chk_path->path_length < FIRST_PATH_ELEMENT_OFFSET ||
+          p_s_chk_path->path_length > MAX_HEIGHT,
+          "PAP-5050: pointer to the key(%p) is NULL or invalid path length(%d)",
+          p_s_key, p_s_chk_path->path_length);
+  RFALSE( !PATH_PLAST_BUFFER(p_s_chk_path)->b_bdev,
+          "PAP-5060: device must not be NODEV");
+
+  if ( comp_keys(get_lkey(p_s_chk_path, p_s_sb), p_s_key) == 1 )
+    /* left delimiting key is bigger, that the key we look for */
+    return 0;
+  //  if ( comp_keys(p_s_key, get_rkey(p_s_chk_path, p_s_sb)) != -1 )
+  if ( comp_keys(get_rkey(p_s_chk_path, p_s_sb), p_s_key) != 1 )
+    /* p_s_key must be less than right delimitiing key */
+    return 0;
+  return 1;
+}
+
+
+inline void decrement_bcount(
+              struct buffer_head  * p_s_bh
+            ) { 
+  if ( p_s_bh ) {
+    if ( atomic_read (&(p_s_bh->b_count)) ) {
+      put_bh(p_s_bh) ;
+      return;
+    }
+    reiserfs_panic(NULL, "PAP-5070: decrement_bcount: trying to free free buffer %b", p_s_bh);
+  }
+}
+
+
+/* Decrement b_count field of the all buffers in the path. */
+void decrement_counters_in_path (
+              struct path * p_s_search_path
+            ) {
+  int n_path_offset = p_s_search_path->path_length;
+
+  RFALSE( n_path_offset < ILLEGAL_PATH_ELEMENT_OFFSET ||
+          n_path_offset > EXTENDED_MAX_HEIGHT - 1,
+          "PAP-5080: invalid path offset of %d", n_path_offset);
+
+  while ( n_path_offset > ILLEGAL_PATH_ELEMENT_OFFSET ) {
+    struct buffer_head * bh;
+
+    bh = PATH_OFFSET_PBUFFER(p_s_search_path, n_path_offset--);
+    decrement_bcount (bh);
+  }
+  p_s_search_path->path_length = ILLEGAL_PATH_ELEMENT_OFFSET;
+}
+
+
+int reiserfs_check_path(struct path *p) {
+  RFALSE( p->path_length != ILLEGAL_PATH_ELEMENT_OFFSET,
+          "path not properly relsed") ;
+  return 0 ;
+}
+
+
+/* Release all buffers in the path. Restore dirty bits clean
+** when preparing the buffer for the log
+**
+** only called from fix_nodes()
+*/
+void  pathrelse_and_restore (
+        struct super_block *s, 
+        struct path * p_s_search_path
+      ) {
+  int n_path_offset = p_s_search_path->path_length;
+
+  RFALSE( n_path_offset < ILLEGAL_PATH_ELEMENT_OFFSET, 
+          "clm-4000: invalid path offset");
+  
+  while ( n_path_offset > ILLEGAL_PATH_ELEMENT_OFFSET )  {
+    reiserfs_restore_prepared_buffer(s, PATH_OFFSET_PBUFFER(p_s_search_path, 
+                                     n_path_offset));
+    brelse(PATH_OFFSET_PBUFFER(p_s_search_path, n_path_offset--));
+  }
+  p_s_search_path->path_length = ILLEGAL_PATH_ELEMENT_OFFSET;
+}
+
+/* Release all buffers in the path. */
+void  pathrelse (
+        struct path * p_s_search_path
+      ) {
+  int n_path_offset = p_s_search_path->path_length;
+
+  RFALSE( n_path_offset < ILLEGAL_PATH_ELEMENT_OFFSET,
+          "PAP-5090: invalid path offset");
+  
+  while ( n_path_offset > ILLEGAL_PATH_ELEMENT_OFFSET )  
+    brelse(PATH_OFFSET_PBUFFER(p_s_search_path, n_path_offset--));
+
+  p_s_search_path->path_length = ILLEGAL_PATH_ELEMENT_OFFSET;
+}
+
+
+
+static int is_leaf (char * buf, int blocksize, struct buffer_head * bh)
+{
+    struct block_head * blkh;
+    struct item_head * ih;
+    int used_space;
+    int prev_location;
+    int i;
+    int nr;
+
+    blkh = (struct block_head *)buf;
+    if ( blkh_level(blkh) != DISK_LEAF_NODE_LEVEL) {
+        reiserfs_warning (NULL, "is_leaf: this should be caught earlier");
+        return 0;
+    }
+
+    nr = blkh_nr_item(blkh);
+    if (nr < 1 || nr > ((blocksize - BLKH_SIZE) / (IH_SIZE + MIN_ITEM_LEN))) {
+        /* item number is too big or too small */
+        reiserfs_warning (NULL, "is_leaf: nr_item seems wrong: %z", bh);
+        return 0;
+    }
+    ih = (struct item_head *)(buf + BLKH_SIZE) + nr - 1;
+    used_space = BLKH_SIZE + IH_SIZE * nr + (blocksize - ih_location (ih));
+    if (used_space != blocksize - blkh_free_space(blkh)) {
+        /* free space does not match to calculated amount of use space */
+        reiserfs_warning (NULL, "is_leaf: free space seems wrong: %z", bh);
+        return 0;
+    }
+
+    // FIXME: it is_leaf will hit performance too much - we may have
+    // return 1 here
+
+    /* check tables of item heads */
+    ih = (struct item_head *)(buf + BLKH_SIZE);
+    prev_location = blocksize;
+    for (i = 0; i < nr; i ++, ih ++) {
+        if ( le_ih_k_type(ih) == TYPE_ANY) {
+            reiserfs_warning (NULL, "is_leaf: wrong item type for item %h",ih);
+            return 0;
+        }
+        if (ih_location (ih) >= blocksize || ih_location (ih) < IH_SIZE * nr) {
+            reiserfs_warning (NULL, "is_leaf: item location seems wrong: %h", ih);
+            return 0;
+        }
+        if (ih_item_len (ih) < 1 || ih_item_len (ih) > MAX_ITEM_LEN (blocksize)) {
+            reiserfs_warning (NULL, "is_leaf: item length seems wrong: %h", ih);
+            return 0;
+        }
+        if (prev_location - ih_location (ih) != ih_item_len (ih)) {
+            reiserfs_warning (NULL, "is_leaf: item location seems wrong (second one): %h", ih);
+            return 0;
+        }
+        prev_location = ih_location (ih);
+    }
+
+    // one may imagine much more checks
+    return 1;
+}
+
+
+/* returns 1 if buf looks like an internal node, 0 otherwise */
+static int is_internal (char * buf, int blocksize, struct buffer_head * bh)
+{
+    struct block_head * blkh;
+    int nr;
+    int used_space;
+
+    blkh = (struct block_head *)buf;
+    nr = blkh_level(blkh);
+    if (nr <= DISK_LEAF_NODE_LEVEL || nr > MAX_HEIGHT) {
+        /* this level is not possible for internal nodes */
+        reiserfs_warning (NULL, "is_internal: this should be caught earlier");
+        return 0;
+    }
+    
+    nr = blkh_nr_item(blkh);
+    if (nr > (blocksize - BLKH_SIZE - DC_SIZE) / (KEY_SIZE + DC_SIZE)) {
+        /* for internal which is not root we might check min number of keys */
+        reiserfs_warning (NULL, "is_internal: number of key seems wrong: %z", bh);
+        return 0;
+    }
+
+    used_space = BLKH_SIZE + KEY_SIZE * nr + DC_SIZE * (nr + 1);
+    if (used_space != blocksize - blkh_free_space(blkh)) {
+        reiserfs_warning (NULL, "is_internal: free space seems wrong: %z", bh);
+        return 0;
+    }
+
+    // one may imagine much more checks
+    return 1;
+}
+
+
+// make sure that bh contains formatted node of reiserfs tree of
+// 'level'-th level
+static int is_tree_node (struct buffer_head * bh, int level)
+{
+    if (B_LEVEL (bh) != level) {
+        reiserfs_warning (NULL, "is_tree_node: node level %d does not match to the expected one %d",
+                B_LEVEL (bh), level);
+        return 0;
+    }
+    if (level == DISK_LEAF_NODE_LEVEL)
+        return is_leaf (bh->b_data, bh->b_size, bh);
+
+    return is_internal (bh->b_data, bh->b_size, bh);
+}
+
+
+
+#define SEARCH_BY_KEY_READA 16
+
+/* The function is NOT SCHEDULE-SAFE! */
+static void search_by_key_reada (struct super_block * s,
+                                 struct buffer_head **bh,
+                                 unsigned long *b, int num)
+{
+    int i,j;
+  
+    for (i = 0 ; i < num ; i++) {
+        bh[i] = sb_getblk (s, b[i]);
+    }
+    for (j = 0 ; j < i ; j++) {
+        /*
+         * note, this needs attention if we are getting rid of the BKL
+         * you have to make sure the prepared bit isn't set on this buffer
+         */
+        if (!buffer_uptodate(bh[j]))
+            ll_rw_block(READA, 1, bh + j);
+        brelse(bh[j]);
+    }
+}
+
+/**************************************************************************
+ * Algorithm   SearchByKey                                                *
+ *             look for item in the Disk S+Tree by its key                *
+ * Input:  p_s_sb   -  super block                                        *
+ *         p_s_key  - pointer to the key to search                        *
+ * Output: ITEM_FOUND, ITEM_NOT_FOUND or IO_ERROR                         *
+ *         p_s_search_path - path from the root to the needed leaf        *
+ **************************************************************************/
+
+/* This function fills up the path from the root to the leaf as it
+   descends the tree looking for the key.  It uses reiserfs_bread to
+   try to find buffers in the cache given their block number.  If it
+   does not find them in the cache it reads them from disk.  For each
+   node search_by_key finds using reiserfs_bread it then uses
+   bin_search to look through that node.  bin_search will find the
+   position of the block_number of the next node if it is looking
+   through an internal node.  If it is looking through a leaf node
+   bin_search will find the position of the item which has key either
+   equal to given key, or which is the maximal key less than the given
+   key.  search_by_key returns a path that must be checked for the
+   correctness of the top of the path but need not be checked for the
+   correctness of the bottom of the path */
+/* The function is NOT SCHEDULE-SAFE! */
+int search_by_key (struct super_block * p_s_sb,
+                   const struct cpu_key * p_s_key, /* Key to search. */
+                   struct path * p_s_search_path, /* This structure was
+                                                     allocated and initialized
+                                                     by the calling
+                                                     function. It is filled up
+                                                     by this function.  */
+                   int n_stop_level /* How far down the tree to search. To
+                                       stop at leaf level - set to
+                                       DISK_LEAF_NODE_LEVEL */
+    ) {
+    int  n_block_number;
+    int  expected_level;
+    struct buffer_head  *       p_s_bh;
+    struct path_element *       p_s_last_element;
+    int                         n_node_level, n_retval;
+    int                         right_neighbor_of_leaf_node;
+    int                         fs_gen;
+    struct buffer_head *reada_bh[SEARCH_BY_KEY_READA];
+    unsigned long      reada_blocks[SEARCH_BY_KEY_READA];
+    int reada_count = 0;
+
+#ifdef CONFIG_REISERFS_CHECK
+    int n_repeat_counter = 0;
+#endif
+    
+    PROC_INFO_INC( p_s_sb, search_by_key );
+    
+    /* As we add each node to a path we increase its count.  This means that
+       we must be careful to release all nodes in a path before we either
+       discard the path struct or re-use the path struct, as we do here. */
+
+    decrement_counters_in_path(p_s_search_path);
+
+    right_neighbor_of_leaf_node = 0;
+
+    /* With each iteration of this loop we search through the items in the
+       current node, and calculate the next current node(next path element)
+       for the next iteration of this loop.. */
+    n_block_number = SB_ROOT_BLOCK (p_s_sb);
+    expected_level = -1;
+    while ( 1 ) {
+
+#ifdef CONFIG_REISERFS_CHECK
+        if ( !(++n_repeat_counter % 50000) )
+            reiserfs_warning (p_s_sb, "PAP-5100: search_by_key: %s:"
+                              "there were %d iterations of while loop "
+                              "looking for key %K",
+                              current->comm, n_repeat_counter, p_s_key);
+#endif
+
+        /* prep path to have another element added to it. */
+        p_s_last_element = PATH_OFFSET_PELEMENT(p_s_search_path, ++p_s_search_path->path_length);
+        fs_gen = get_generation (p_s_sb);
+
+        /* Read the next tree node, and set the last element in the path to
+           have a pointer to it. */
+        if ((p_s_bh = p_s_last_element->pe_buffer =
+             sb_getblk(p_s_sb, n_block_number)) ) {
+            if (!buffer_uptodate(p_s_bh) && reada_count > 1) {
+                search_by_key_reada (p_s_sb, reada_bh,
+                                     reada_blocks, reada_count);
+            }
+            ll_rw_block(READ, 1, &p_s_bh);
+            wait_on_buffer(p_s_bh);
+            if (!buffer_uptodate(p_s_bh))
+                goto io_error;
+        } else {
+io_error:
+            p_s_search_path->path_length --;
+            pathrelse(p_s_search_path);
+            return IO_ERROR;
+        }
+        reada_count = 0;
+        if (expected_level == -1)
+                expected_level = SB_TREE_HEIGHT (p_s_sb);
+        expected_level --;
+
+        /* It is possible that schedule occurred. We must check whether the key
+           to search is still in the tree rooted from the current buffer. If
+           not then repeat search from the root. */
+        if ( fs_changed (fs_gen, p_s_sb) && 
+            (!B_IS_IN_TREE (p_s_bh) ||
+             B_LEVEL(p_s_bh) != expected_level ||
+             !key_in_buffer(p_s_search_path, p_s_key, p_s_sb))) {
+            PROC_INFO_INC( p_s_sb, search_by_key_fs_changed );
+            PROC_INFO_INC( p_s_sb, search_by_key_restarted );
+            PROC_INFO_INC( p_s_sb, sbk_restarted[ expected_level - 1 ] );
+            decrement_counters_in_path(p_s_search_path);
+            
+            /* Get the root block number so that we can repeat the search
+               starting from the root. */
+            n_block_number = SB_ROOT_BLOCK (p_s_sb);
+            expected_level = -1;
+            right_neighbor_of_leaf_node = 0;
+            
+            /* repeat search from the root */
+            continue;
+        }
+
+        /* only check that the key is in the buffer if p_s_key is not
+           equal to the MAX_KEY. Latter case is only possible in
+           "finish_unfinished()" processing during mount. */
+        RFALSE( comp_keys( &MAX_KEY, p_s_key ) &&
+                ! key_in_buffer(p_s_search_path, p_s_key, p_s_sb),
+                "PAP-5130: key is not in the buffer");
+#ifdef CONFIG_REISERFS_CHECK
+        if ( cur_tb ) {
+            print_cur_tb ("5140");
+            reiserfs_panic(p_s_sb, "PAP-5140: search_by_key: schedule occurred in do_balance!");
+        }
+#endif
+
+        // make sure, that the node contents look like a node of
+        // certain level
+        if (!is_tree_node (p_s_bh, expected_level)) {
+            reiserfs_warning (p_s_sb, "vs-5150: search_by_key: "
+                              "invalid format found in block %ld. Fsck?",
+                              p_s_bh->b_blocknr);
+            pathrelse (p_s_search_path);
+            return IO_ERROR;
+        }
+        
+        /* ok, we have acquired next formatted node in the tree */
+        n_node_level = B_LEVEL (p_s_bh);
+
+        PROC_INFO_BH_STAT( p_s_sb, p_s_bh, n_node_level - 1 );
+
+        RFALSE( n_node_level < n_stop_level,
+                "vs-5152: tree level (%d) is less than stop level (%d)",
+                n_node_level, n_stop_level);
+
+        n_retval = bin_search( p_s_key, B_N_PITEM_HEAD(p_s_bh, 0),
+                B_NR_ITEMS(p_s_bh),
+                ( n_node_level == DISK_LEAF_NODE_LEVEL ) ? IH_SIZE : KEY_SIZE,
+                &(p_s_last_element->pe_position));
+        if (n_node_level == n_stop_level) {
+            return n_retval;
+        }
+
+        /* we are not in the stop level */
+        if (n_retval == ITEM_FOUND)
+            /* item has been found, so we choose the pointer which is to the right of the found one */
+            p_s_last_element->pe_position++;
+
+        /* if item was not found we choose the position which is to
+           the left of the found item. This requires no code,
+           bin_search did it already.*/
+
+        /* So we have chosen a position in the current node which is
+           an internal node.  Now we calculate child block number by
+           position in the node. */
+        n_block_number = B_N_CHILD_NUM(p_s_bh, p_s_last_element->pe_position);
+
+        /* if we are going to read leaf nodes, try for read ahead as well */
+        if ((p_s_search_path->reada & PATH_READA) &&
+            n_node_level == DISK_LEAF_NODE_LEVEL + 1)
+        {
+            int pos = p_s_last_element->pe_position;
+            int limit = B_NR_ITEMS(p_s_bh);
+            struct reiserfs_key *le_key;
+
+            if (p_s_search_path->reada & PATH_READA_BACK)
+                limit = 0;
+            while(reada_count < SEARCH_BY_KEY_READA) {
+                if (pos == limit)
+                    break;
+                reada_blocks[reada_count++] = B_N_CHILD_NUM(p_s_bh, pos);
+                if (p_s_search_path->reada & PATH_READA_BACK)
+                    pos--;
+                else
+                    pos++;
+
+                /*
+                 * check to make sure we're in the same object
+                 */
+                le_key = B_N_PDELIM_KEY(p_s_bh, pos);
+                if (le32_to_cpu(le_key->k_objectid) !=
+                    p_s_key->on_disk_key.k_objectid)
+                {
+                    break;
+                }
+            }
+        }
+    }
+}
+
+
+/* Form the path to an item and position in this item which contains
+   file byte defined by p_s_key. If there is no such item
+   corresponding to the key, we point the path to the item with
+   maximal key less than p_s_key, and *p_n_pos_in_item is set to one
+   past the last entry/byte in the item.  If searching for entry in a
+   directory item, and it is not found, *p_n_pos_in_item is set to one
+   entry more than the entry with maximal key which is less than the
+   sought key.
+
+   Note that if there is no entry in this same node which is one more,
+   then we point to an imaginary entry.  for direct items, the
+   position is in units of bytes, for indirect items the position is
+   in units of blocknr entries, for directory items the position is in
+   units of directory entries.  */
+
+/* The function is NOT SCHEDULE-SAFE! */
+int search_for_position_by_key (struct super_block  * p_s_sb,         /* Pointer to the super block.          */
+                                const struct cpu_key  * p_cpu_key,      /* Key to search (cpu variable)         */
+                                struct path         * p_s_search_path /* Filled up by this function.          */
+    ) {
+    struct item_head    * p_le_ih; /* pointer to on-disk structure */
+    int                   n_blk_size;
+    loff_t item_offset, offset;
+    struct reiserfs_dir_entry de;
+    int retval;
+
+    /* If searching for directory entry. */
+    if ( is_direntry_cpu_key (p_cpu_key) )
+        return  search_by_entry_key (p_s_sb, p_cpu_key, p_s_search_path, &de);
+
+    /* If not searching for directory entry. */
+    
+    /* If item is found. */
+    retval = search_item (p_s_sb, p_cpu_key, p_s_search_path);
+    if (retval == IO_ERROR)
+        return retval;
+    if ( retval == ITEM_FOUND )  {
+
+        RFALSE( ! ih_item_len(
+                B_N_PITEM_HEAD(PATH_PLAST_BUFFER(p_s_search_path),
+                               PATH_LAST_POSITION(p_s_search_path))),
+                "PAP-5165: item length equals zero");
+
+        pos_in_item(p_s_search_path) = 0;
+        return POSITION_FOUND;
+    }
+
+    RFALSE( ! PATH_LAST_POSITION(p_s_search_path),
+            "PAP-5170: position equals zero");
+
+    /* Item is not found. Set path to the previous item. */
+    p_le_ih = B_N_PITEM_HEAD(PATH_PLAST_BUFFER(p_s_search_path), --PATH_LAST_POSITION(p_s_search_path));
+    n_blk_size = p_s_sb->s_blocksize;
+
+    if (comp_short_keys (&(p_le_ih->ih_key), p_cpu_key)) {
+        return FILE_NOT_FOUND;
+    }
+
+    // FIXME: quite ugly this far
+
+    item_offset = le_ih_k_offset (p_le_ih);
+    offset = cpu_key_k_offset (p_cpu_key);
+
+    /* Needed byte is contained in the item pointed to by the path.*/
+    if (item_offset <= offset &&
+        item_offset + op_bytes_number (p_le_ih, n_blk_size) > offset) {
+        pos_in_item (p_s_search_path) = offset - item_offset;
+        if ( is_indirect_le_ih(p_le_ih) ) {
+            pos_in_item (p_s_search_path) /= n_blk_size;
+        }
+        return POSITION_FOUND;
+    }
+
+    /* Needed byte is not contained in the item pointed to by the
+     path. Set pos_in_item out of the item. */
+    if ( is_indirect_le_ih (p_le_ih) )
+        pos_in_item (p_s_search_path) = ih_item_len(p_le_ih) / UNFM_P_SIZE;
+    else
+        pos_in_item (p_s_search_path) = ih_item_len( p_le_ih );
+  
+    return POSITION_NOT_FOUND;
+}
+
+
+/* Compare given item and item pointed to by the path. */
+int comp_items (const struct item_head * stored_ih, const struct path * p_s_path)
+{
+    struct buffer_head  * p_s_bh;
+    struct item_head    * ih;
+
+    /* Last buffer at the path is not in the tree. */
+    if ( ! B_IS_IN_TREE(p_s_bh = PATH_PLAST_BUFFER(p_s_path)) )
+        return 1;
+
+    /* Last path position is invalid. */
+    if ( PATH_LAST_POSITION(p_s_path) >= B_NR_ITEMS(p_s_bh) )
+        return 1;
+
+    /* we need only to know, whether it is the same item */
+    ih = get_ih (p_s_path);
+    return memcmp (stored_ih, ih, IH_SIZE);
+}
+
+
+/* unformatted nodes are not logged anymore, ever.  This is safe
+** now
+*/
+#define held_by_others(bh) (atomic_read(&(bh)->b_count) > 1)
+
+// block can not be forgotten as it is in I/O or held by someone
+#define block_in_use(bh) (buffer_locked(bh) || (held_by_others(bh)))
+
+
+
+// prepare for delete or cut of direct item
+static inline int prepare_for_direct_item (struct path * path,
+                                           struct item_head * le_ih,
+                                           struct inode * inode,
+                                           loff_t new_file_length,
+                                           int * cut_size)
+{
+    loff_t round_len;
+
+
+    if ( new_file_length == max_reiserfs_offset (inode) ) {
+        /* item has to be deleted */
+        *cut_size = -(IH_SIZE + ih_item_len(le_ih));
+        return M_DELETE;
+    }
+        
+    // new file gets truncated
+    if (get_inode_item_key_version (inode) == KEY_FORMAT_3_6) {
+        // 
+        round_len = ROUND_UP (new_file_length); 
+        /* this was n_new_file_length < le_ih ... */
+        if ( round_len < le_ih_k_offset (le_ih) )  {
+            *cut_size = -(IH_SIZE + ih_item_len(le_ih));
+            return M_DELETE; /* Delete this item. */
+        }
+        /* Calculate first position and size for cutting from item. */
+        pos_in_item (path) = round_len - (le_ih_k_offset (le_ih) - 1);
+        *cut_size = -(ih_item_len(le_ih) - pos_in_item(path));
+        
+        return M_CUT; /* Cut from this item. */
+    }
+
+
+    // old file: items may have any length
+
+    if ( new_file_length < le_ih_k_offset (le_ih) )  {
+        *cut_size = -(IH_SIZE + ih_item_len(le_ih));
+        return M_DELETE; /* Delete this item. */
+    }
+    /* Calculate first position and size for cutting from item. */
+    *cut_size = -(ih_item_len(le_ih) -
+                      (pos_in_item (path) = new_file_length + 1 - le_ih_k_offset (le_ih)));
+    return M_CUT; /* Cut from this item. */
+}
+
+
+static inline int prepare_for_direntry_item (struct path * path,
+                                             struct item_head * le_ih,
+                                             struct inode * inode,
+                                             loff_t new_file_length,
+                                             int * cut_size)
+{
+    if (le_ih_k_offset (le_ih) == DOT_OFFSET && 
+        new_file_length == max_reiserfs_offset (inode)) {
+        RFALSE( ih_entry_count (le_ih) != 2,
+                "PAP-5220: incorrect empty directory item (%h)", le_ih);
+        *cut_size = -(IH_SIZE + ih_item_len(le_ih));
+        return M_DELETE; /* Delete the directory item containing "." and ".." entry. */
+    }
+    
+    if ( ih_entry_count (le_ih) == 1 )  {
+        /* Delete the directory item such as there is one record only
+           in this item*/
+        *cut_size = -(IH_SIZE + ih_item_len(le_ih));
+        return M_DELETE;
+    }
+    
+    /* Cut one record from the directory item. */
+    *cut_size = -(DEH_SIZE + entry_length (get_last_bh (path), le_ih, pos_in_item (path)));
+    return M_CUT; 
+}
+
+
+/*  If the path points to a directory or direct item, calculate mode and the size cut, for balance.
+    If the path points to an indirect item, remove some number of its unformatted nodes.
+    In case of file truncate calculate whether this item must be deleted/truncated or last
+    unformatted node of this item will be converted to a direct item.
+    This function returns a determination of what balance mode the calling function should employ. */
+static char  prepare_for_delete_or_cut(
+                                       struct reiserfs_transaction_handle *th, 
+                                       struct inode * inode,
+                                       struct path         * p_s_path,
+                                       const struct cpu_key      * p_s_item_key,
+                                       int                 * p_n_removed,      /* Number of unformatted nodes which were removed
+                                                                                  from end of the file. */
+                                       int                 * p_n_cut_size,
+                                       unsigned long long    n_new_file_length /* MAX_KEY_OFFSET in case of delete. */
+    ) {
+    struct super_block  * p_s_sb = inode->i_sb;
+    struct item_head    * p_le_ih = PATH_PITEM_HEAD(p_s_path);
+    struct buffer_head  * p_s_bh = PATH_PLAST_BUFFER(p_s_path);
+
+    BUG_ON (!th->t_trans_id);
+
+    /* Stat_data item. */
+    if ( is_statdata_le_ih (p_le_ih) ) {
+
+        RFALSE( n_new_file_length != max_reiserfs_offset (inode),
+                "PAP-5210: mode must be M_DELETE");
+
+        *p_n_cut_size = -(IH_SIZE + ih_item_len(p_le_ih));
+        return M_DELETE;
+    }
+
+
+    /* Directory item. */
+    if ( is_direntry_le_ih (p_le_ih) )
+        return prepare_for_direntry_item (p_s_path, p_le_ih, inode, n_new_file_length, p_n_cut_size);
+
+    /* Direct item. */
+    if ( is_direct_le_ih (p_le_ih) )
+        return prepare_for_direct_item (p_s_path, p_le_ih, inode, n_new_file_length, p_n_cut_size);
+
+
+    /* Case of an indirect item. */
+    {
+        int                   n_unfm_number,    /* Number of the item unformatted nodes. */
+            n_counter,
+            n_blk_size;
+        __u32               * p_n_unfm_pointer; /* Pointer to the unformatted node number. */
+        __u32 tmp;
+        struct item_head      s_ih;           /* Item header. */
+        char                  c_mode;           /* Returned mode of the balance. */
+        int need_research;
+
+
+        n_blk_size = p_s_sb->s_blocksize;
+
+        /* Search for the needed object indirect item until there are no unformatted nodes to be removed. */
+        do  {
+            need_research = 0;
+            p_s_bh = PATH_PLAST_BUFFER(p_s_path);
+            /* Copy indirect item header to a temp variable. */
+            copy_item_head(&s_ih, PATH_PITEM_HEAD(p_s_path));
+            /* Calculate number of unformatted nodes in this item. */
+            n_unfm_number = I_UNFM_NUM(&s_ih);
+
+            RFALSE( ! is_indirect_le_ih(&s_ih) || ! n_unfm_number ||
+                    pos_in_item (p_s_path) + 1 !=  n_unfm_number,
+                    "PAP-5240: invalid item %h "
+                    "n_unfm_number = %d *p_n_pos_in_item = %d", 
+                    &s_ih, n_unfm_number, pos_in_item (p_s_path));
+
+            /* Calculate balance mode and position in the item to remove unformatted nodes. */
+            if ( n_new_file_length == max_reiserfs_offset (inode) ) {/* Case of delete. */
+                pos_in_item (p_s_path) = 0;
+                *p_n_cut_size = -(IH_SIZE + ih_item_len(&s_ih));
+                c_mode = M_DELETE;
+            }
+            else  { /* Case of truncate. */
+                if ( n_new_file_length < le_ih_k_offset (&s_ih) )  {
+                    pos_in_item (p_s_path) = 0;
+                    *p_n_cut_size = -(IH_SIZE + ih_item_len(&s_ih));
+                    c_mode = M_DELETE; /* Delete this item. */
+                }
+                else  {
+                    /* indirect item must be truncated starting from *p_n_pos_in_item-th position */
+                    pos_in_item (p_s_path) = (n_new_file_length + n_blk_size - le_ih_k_offset (&s_ih) ) >> p_s_sb->s_blocksize_bits;
+
+                    RFALSE( pos_in_item (p_s_path) > n_unfm_number,
+                            "PAP-5250: invalid position in the item");
+
+                    /* Either convert last unformatted node of indirect item to direct item or increase
+                       its free space.  */
+                    if ( pos_in_item (p_s_path) == n_unfm_number )  {
+                        *p_n_cut_size = 0; /* Nothing to cut. */
+                        return M_CONVERT; /* Maybe convert last unformatted node to the direct item. */
+                    }
+                    /* Calculate size to cut. */
+                    *p_n_cut_size = -(ih_item_len(&s_ih) - pos_in_item(p_s_path) * UNFM_P_SIZE);
+
+                    c_mode = M_CUT;     /* Cut from this indirect item. */
+                }
+            }
+
+            RFALSE( n_unfm_number <= pos_in_item (p_s_path),
+                    "PAP-5260: invalid position in the indirect item");
+
+            /* pointers to be cut */
+            n_unfm_number -= pos_in_item (p_s_path);
+            /* Set pointer to the last unformatted node pointer that is to be cut. */
+            p_n_unfm_pointer = (__u32 *)B_I_PITEM(p_s_bh, &s_ih) + I_UNFM_NUM(&s_ih) - 1 - *p_n_removed;
+
+
+            /* We go through the unformatted nodes pointers of the indirect
+               item and look for the unformatted nodes in the cache. If we
+               found some of them we free it, zero corresponding indirect item
+               entry and log buffer containing that indirect item. For this we
+               need to prepare last path element for logging. If some
+               unformatted node has b_count > 1 we must not free this
+               unformatted node since it is in use. */
+            reiserfs_prepare_for_journal(p_s_sb, p_s_bh, 1);
+            // note: path could be changed, first line in for loop takes care
+            // of it
+
+            for (n_counter = *p_n_removed;
+                 n_counter < n_unfm_number; n_counter++, p_n_unfm_pointer-- ) {
+
+                cond_resched();
+                if (item_moved (&s_ih, p_s_path)) {
+                    need_research = 1 ;
+                    break;
+                }
+                RFALSE( p_n_unfm_pointer < (__u32 *)B_I_PITEM(p_s_bh, &s_ih) ||
+                        p_n_unfm_pointer > (__u32 *)B_I_PITEM(p_s_bh, &s_ih) + I_UNFM_NUM(&s_ih) - 1,
+                        "vs-5265: pointer out of range");
+
+                /* Hole, nothing to remove. */
+                if ( ! get_block_num(p_n_unfm_pointer,0) )  {
+                        (*p_n_removed)++;
+                        continue;
+                }
+
+                (*p_n_removed)++;
+
+                tmp = get_block_num(p_n_unfm_pointer,0);
+                put_block_num(p_n_unfm_pointer, 0, 0);
+                journal_mark_dirty (th, p_s_sb, p_s_bh);
+                reiserfs_free_block(th, inode, tmp, 1);
+                if ( item_moved (&s_ih, p_s_path) )  {
+                        need_research = 1;
+                        break ;
+                }
+            }
+
+            /* a trick.  If the buffer has been logged, this
+            ** will do nothing.  If we've broken the loop without
+            ** logging it, it will restore the buffer
+            **
+            */
+            reiserfs_restore_prepared_buffer(p_s_sb, p_s_bh);
+
+            /* This loop can be optimized. */
+        } while ( (*p_n_removed < n_unfm_number || need_research) &&
+                  search_for_position_by_key(p_s_sb, p_s_item_key, p_s_path) == POSITION_FOUND );
+
+        RFALSE( *p_n_removed < n_unfm_number, 
+                "PAP-5310: indirect item is not found");
+        RFALSE( item_moved (&s_ih, p_s_path), 
+                "after while, comp failed, retry") ;
+
+        if (c_mode == M_CUT)
+            pos_in_item (p_s_path) *= UNFM_P_SIZE;
+        return c_mode;
+    }
+}
+
+/* Calculate number of bytes which will be deleted or cut during balance */
+static int calc_deleted_bytes_number(
+    struct  tree_balance  * p_s_tb,
+    char                    c_mode
+    ) {
+    int                     n_del_size;
+    struct  item_head     * p_le_ih = PATH_PITEM_HEAD(p_s_tb->tb_path);
+
+    if ( is_statdata_le_ih (p_le_ih) )
+        return 0;
+
+    n_del_size = ( c_mode == M_DELETE ) ? ih_item_len(p_le_ih) : -p_s_tb->insert_size[0];
+    if ( is_direntry_le_ih (p_le_ih) ) {
+        // return EMPTY_DIR_SIZE; /* We delete emty directoris only. */
+        // we can't use EMPTY_DIR_SIZE, as old format dirs have a different
+        // empty size.  ick. FIXME, is this right?
+        //
+        return n_del_size ;
+    }
+
+    if ( is_indirect_le_ih (p_le_ih) )
+        n_del_size = (n_del_size/UNFM_P_SIZE)*
+          (PATH_PLAST_BUFFER(p_s_tb->tb_path)->b_size);// - get_ih_free_space (p_le_ih);
+    return n_del_size;
+}
+
+static void init_tb_struct(
+    struct reiserfs_transaction_handle *th,
+    struct tree_balance * p_s_tb,
+    struct super_block  * p_s_sb,
+    struct path         * p_s_path,
+    int                   n_size
+    ) {
+
+    BUG_ON (!th->t_trans_id);
+
+    memset (p_s_tb,'\0',sizeof(struct tree_balance));
+    p_s_tb->transaction_handle = th ;
+    p_s_tb->tb_sb = p_s_sb;
+    p_s_tb->tb_path = p_s_path;
+    PATH_OFFSET_PBUFFER(p_s_path, ILLEGAL_PATH_ELEMENT_OFFSET) = NULL;
+    PATH_OFFSET_POSITION(p_s_path, ILLEGAL_PATH_ELEMENT_OFFSET) = 0;
+    p_s_tb->insert_size[0] = n_size;
+}
+
+
+
+void padd_item (char * item, int total_length, int length)
+{
+    int i;
+
+    for (i = total_length; i > length; )
+        item [--i] = 0;
+}
+
+#ifdef REISERQUOTA_DEBUG
+char key2type(struct reiserfs_key *ih)
+{
+  if (is_direntry_le_key(2, ih))
+    return 'd';
+  if (is_direct_le_key(2, ih))
+    return 'D';
+  if (is_indirect_le_key(2, ih))
+    return 'i';
+  if (is_statdata_le_key(2, ih))
+    return 's';
+  return 'u';
+}
+
+char head2type(struct item_head *ih)
+{
+  if (is_direntry_le_ih(ih))
+    return 'd';
+  if (is_direct_le_ih(ih))
+    return 'D';
+  if (is_indirect_le_ih(ih))
+    return 'i';
+  if (is_statdata_le_ih(ih))
+    return 's';
+  return 'u';
+}
+#endif
+
+/* Delete object item. */
+int reiserfs_delete_item (struct reiserfs_transaction_handle *th, 
+                          struct path * p_s_path, /* Path to the deleted item. */
+                          const struct cpu_key * p_s_item_key, /* Key to search for the deleted item.  */
+                          struct inode * p_s_inode,/* inode is here just to update i_blocks and quotas */
+                          struct buffer_head  * p_s_un_bh)    /* NULL or unformatted node pointer.    */
+{
+    struct super_block * p_s_sb = p_s_inode->i_sb;
+    struct tree_balance   s_del_balance;
+    struct item_head      s_ih;
+    struct item_head      *q_ih;
+    int                   quota_cut_bytes;
+    int                   n_ret_value,
+        n_del_size,
+        n_removed;
+
+#ifdef CONFIG_REISERFS_CHECK
+    char                  c_mode;
+    int                 n_iter = 0;
+#endif
+
+    BUG_ON (!th->t_trans_id);
+
+    init_tb_struct(th, &s_del_balance, p_s_sb, p_s_path, 0/*size is unknown*/);
+
+    while ( 1 ) {
+        n_removed = 0;
+
+#ifdef CONFIG_REISERFS_CHECK
+        n_iter++;
+        c_mode =
+#endif
+            prepare_for_delete_or_cut(th, p_s_inode, p_s_path, p_s_item_key, &n_removed, &n_del_size, max_reiserfs_offset (p_s_inode));
+
+        RFALSE( c_mode != M_DELETE, "PAP-5320: mode must be M_DELETE");
+
+        copy_item_head(&s_ih, PATH_PITEM_HEAD(p_s_path));
+        s_del_balance.insert_size[0] = n_del_size;
+
+        n_ret_value = fix_nodes(M_DELETE, &s_del_balance, NULL, NULL);
+        if ( n_ret_value != REPEAT_SEARCH )
+            break;
+
+        PROC_INFO_INC( p_s_sb, delete_item_restarted );
+
+        // file system changed, repeat search
+        n_ret_value = search_for_position_by_key(p_s_sb, p_s_item_key, p_s_path);
+        if (n_ret_value == IO_ERROR)
+            break;
+        if (n_ret_value == FILE_NOT_FOUND) {
+            reiserfs_warning (p_s_sb, "vs-5340: reiserfs_delete_item: "
+                              "no items of the file %K found", p_s_item_key);
+            break;
+        }
+    } /* while (1) */
+
+    if ( n_ret_value != CARRY_ON ) {
+        unfix_nodes(&s_del_balance);
+        return 0;
+    }
+
+    // reiserfs_delete_item returns item length when success
+    n_ret_value = calc_deleted_bytes_number(&s_del_balance, M_DELETE);
+    q_ih = get_ih(p_s_path) ;
+    quota_cut_bytes = ih_item_len(q_ih) ;
+
+    /* hack so the quota code doesn't have to guess if the file
+    ** has a tail.  On tail insert, we allocate quota for 1 unformatted node.
+    ** We test the offset because the tail might have been
+    ** split into multiple items, and we only want to decrement for
+    ** the unfm node once
+    */
+    if (!S_ISLNK (p_s_inode->i_mode) && is_direct_le_ih(q_ih)) {
+        if ((le_ih_k_offset(q_ih) & (p_s_sb->s_blocksize - 1)) == 1) {
+            quota_cut_bytes = p_s_sb->s_blocksize + UNFM_P_SIZE;
+        } else {
+            quota_cut_bytes = 0 ;
+        }
+    }
+
+    if ( p_s_un_bh )  {
+        int off;
+        char *data ;
+
+        /* We are in direct2indirect conversion, so move tail contents
+           to the unformatted node */
+        /* note, we do the copy before preparing the buffer because we
+        ** don't care about the contents of the unformatted node yet.
+        ** the only thing we really care about is the direct item's data
+        ** is in the unformatted node.
+        **
+        ** Otherwise, we would have to call reiserfs_prepare_for_journal on
+        ** the unformatted node, which might schedule, meaning we'd have to
+        ** loop all the way back up to the start of the while loop.
+        **
+        ** The unformatted node must be dirtied later on.  We can't be
+        ** sure here if the entire tail has been deleted yet.
+        **
+        ** p_s_un_bh is from the page cache (all unformatted nodes are
+        ** from the page cache) and might be a highmem page.  So, we
+        ** can't use p_s_un_bh->b_data.
+        ** -clm
+        */
+
+        data = kmap_atomic(p_s_un_bh->b_page, KM_USER0);
+        off = ((le_ih_k_offset (&s_ih) - 1) & (PAGE_CACHE_SIZE - 1));
+        memcpy(data + off,
+               B_I_PITEM(PATH_PLAST_BUFFER(p_s_path), &s_ih), n_ret_value);
+        kunmap_atomic(data, KM_USER0);
+    }
+    /* Perform balancing after all resources have been collected at once. */ 
+    do_balance(&s_del_balance, NULL, NULL, M_DELETE);
+
+#ifdef REISERQUOTA_DEBUG
+    reiserfs_debug (p_s_sb, REISERFS_DEBUG_CODE, "reiserquota delete_item(): freeing %u, id=%u type=%c", quota_cut_bytes, p_s_inode->i_uid, head2type(&s_ih));
+#endif
+    DQUOT_FREE_SPACE_NODIRTY(p_s_inode, quota_cut_bytes);
+
+    /* Return deleted body length */
+    return n_ret_value;
+}
+
+
+/* Summary Of Mechanisms For Handling Collisions Between Processes:
+
+ deletion of the body of the object is performed by iput(), with the
+ result that if multiple processes are operating on a file, the
+ deletion of the body of the file is deferred until the last process
+ that has an open inode performs its iput().
+
+ writes and truncates are protected from collisions by use of
+ semaphores.
+
+ creates, linking, and mknod are protected from collisions with other
+ processes by making the reiserfs_add_entry() the last step in the
+ creation, and then rolling back all changes if there was a collision.
+ - Hans
+*/
+
+
+/* this deletes item which never gets split */
+void reiserfs_delete_solid_item (struct reiserfs_transaction_handle *th,
+                                 struct inode *inode,
+                                 struct reiserfs_key * key)
+{
+    struct tree_balance tb;
+    INITIALIZE_PATH (path);
+    int item_len = 0;
+    int tb_init = 0 ;
+    struct cpu_key cpu_key;
+    int retval;
+    int quota_cut_bytes = 0;
+
+    BUG_ON (!th->t_trans_id);
+    
+    le_key2cpu_key (&cpu_key, key);
+    
+    while (1) {
+        retval = search_item (th->t_super, &cpu_key, &path);
+        if (retval == IO_ERROR) {
+            reiserfs_warning (th->t_super,
+                              "vs-5350: reiserfs_delete_solid_item: "
+                              "i/o failure occurred trying to delete %K",
+                              &cpu_key);
+            break;
+        }
+        if (retval != ITEM_FOUND) {
+            pathrelse (&path);
+            // No need for a warning, if there is just no free space to insert '..' item into the newly-created subdir
+            if ( !( (unsigned long long) GET_HASH_VALUE (le_key_k_offset (le_key_version (key), key)) == 0 && \
+                 (unsigned long long) GET_GENERATION_NUMBER (le_key_k_offset (le_key_version (key), key)) == 1 ) )
+                reiserfs_warning (th->t_super, "vs-5355: reiserfs_delete_solid_item: %k not found", key);
+            break;
+        }
+        if (!tb_init) {
+            tb_init = 1 ;
+            item_len = ih_item_len( PATH_PITEM_HEAD(&path) );
+            init_tb_struct (th, &tb, th->t_super, &path, - (IH_SIZE + item_len));
+        }
+        quota_cut_bytes = ih_item_len(PATH_PITEM_HEAD(&path)) ;
+
+        retval = fix_nodes (M_DELETE, &tb, NULL, NULL);
+        if (retval == REPEAT_SEARCH) {
+            PROC_INFO_INC( th -> t_super, delete_solid_item_restarted );
+            continue;
+        }
+
+        if (retval == CARRY_ON) {
+            do_balance (&tb, NULL, NULL, M_DELETE);
+            if (inode) {        /* Should we count quota for item? (we don't count quotas for save-links) */
+#ifdef REISERQUOTA_DEBUG
+                reiserfs_debug (th->t_super, REISERFS_DEBUG_CODE, "reiserquota delete_solid_item(): freeing %u id=%u type=%c", quota_cut_bytes, inode->i_uid, key2type(key));
+#endif
+                DQUOT_FREE_SPACE_NODIRTY(inode, quota_cut_bytes);
+            }
+            break;
+        }
+
+        // IO_ERROR, NO_DISK_SPACE, etc
+        reiserfs_warning (th->t_super, "vs-5360: reiserfs_delete_solid_item: "
+                          "could not delete %K due to fix_nodes failure", &cpu_key);
+        unfix_nodes (&tb);
+        break;
+    }
+
+    reiserfs_check_path(&path) ;
+}
+
+
+int reiserfs_delete_object (struct reiserfs_transaction_handle *th, struct inode * inode)
+{
+    int err;
+    inode->i_size = 0;
+    BUG_ON (!th->t_trans_id);
+
+    /* for directory this deletes item containing "." and ".." */
+    err = reiserfs_do_truncate (th, inode, NULL, 0/*no timestamp updates*/);
+    if (err)
+        return err;
+    
+#if defined( USE_INODE_GENERATION_COUNTER )
+    if( !old_format_only ( th -> t_super ) )
+      {
+       __u32 *inode_generation;
+       
+       inode_generation = 
+         &REISERFS_SB(th -> t_super) -> s_rs -> s_inode_generation;
+       *inode_generation = cpu_to_le32( le32_to_cpu( *inode_generation ) + 1 );
+      }
+/* USE_INODE_GENERATION_COUNTER */
+#endif
+    reiserfs_delete_solid_item (th, inode, INODE_PKEY (inode));
+
+    return err;
+}
+
+static void
+unmap_buffers(struct page *page, loff_t pos) {
+    struct buffer_head *bh ;
+    struct buffer_head *head ;
+    struct buffer_head *next ;
+    unsigned long tail_index ;
+    unsigned long cur_index ;
+
+    if (page) {
+        if (page_has_buffers(page)) {
+            tail_index = pos & (PAGE_CACHE_SIZE - 1) ;
+            cur_index = 0 ;
+            head = page_buffers(page) ;
+            bh = head ;
+            do {
+                next = bh->b_this_page ;
+
+                /* we want to unmap the buffers that contain the tail, and
+                ** all the buffers after it (since the tail must be at the
+                ** end of the file).  We don't want to unmap file data
+                ** before the tail, since it might be dirty and waiting to
+                ** reach disk
+                */
+                cur_index += bh->b_size ;
+                if (cur_index > tail_index) {
+                    reiserfs_unmap_buffer(bh) ;
+                }
+                bh = next ;
+            } while (bh != head) ;
+            if ( PAGE_SIZE == bh->b_size ) {
+                clear_page_dirty(page);
+            }
+        }
+    }
+}
+
+static int maybe_indirect_to_direct (struct reiserfs_transaction_handle *th, 
+                              struct inode * p_s_inode,
+                              struct page *page, 
+                              struct path         * p_s_path,
+                              const struct cpu_key      * p_s_item_key,
+                              loff_t         n_new_file_size,
+                              char                * p_c_mode
+                              ) {
+    struct super_block * p_s_sb = p_s_inode->i_sb;
+    int n_block_size = p_s_sb->s_blocksize;
+    int cut_bytes;
+    BUG_ON (!th->t_trans_id);
+
+    if (n_new_file_size != p_s_inode->i_size)
+        BUG ();
+
+    /* the page being sent in could be NULL if there was an i/o error
+    ** reading in the last block.  The user will hit problems trying to
+    ** read the file, but for now we just skip the indirect2direct
+    */
+    if (atomic_read(&p_s_inode->i_count) > 1 || 
+        !tail_has_to_be_packed (p_s_inode) || 
+        !page || (REISERFS_I(p_s_inode)->i_flags & i_nopack_mask)) {
+        // leave tail in an unformatted node    
+        *p_c_mode = M_SKIP_BALANCING;
+        cut_bytes = n_block_size - (n_new_file_size & (n_block_size - 1));
+        pathrelse(p_s_path);
+        return cut_bytes;
+    }
+    /* Permorm the conversion to a direct_item. */
+    /*return indirect_to_direct (p_s_inode, p_s_path, p_s_item_key, n_new_file_size, p_c_mode);*/
+    return indirect2direct (th, p_s_inode, page, p_s_path, p_s_item_key, n_new_file_size, p_c_mode);
+}
+
+
+/* we did indirect_to_direct conversion. And we have inserted direct
+   item successesfully, but there were no disk space to cut unfm
+   pointer being converted. Therefore we have to delete inserted
+   direct item(s) */
+static void indirect_to_direct_roll_back (struct reiserfs_transaction_handle *th, struct inode * inode, struct path * path)
+{
+    struct cpu_key tail_key;
+    int tail_len;
+    int removed;
+    BUG_ON (!th->t_trans_id);
+
+    make_cpu_key (&tail_key, inode, inode->i_size + 1, TYPE_DIRECT, 4);// !!!!
+    tail_key.key_length = 4;
+
+    tail_len = (cpu_key_k_offset (&tail_key) & (inode->i_sb->s_blocksize - 1)) - 1;
+    while (tail_len) {
+        /* look for the last byte of the tail */
+        if (search_for_position_by_key (inode->i_sb, &tail_key, path) == POSITION_NOT_FOUND)
+            reiserfs_panic (inode->i_sb, "vs-5615: indirect_to_direct_roll_back: found invalid item");
+        RFALSE( path->pos_in_item != ih_item_len(PATH_PITEM_HEAD (path)) - 1,
+                "vs-5616: appended bytes found");
+        PATH_LAST_POSITION (path) --;
+        
+        removed = reiserfs_delete_item (th, path, &tail_key, inode, NULL/*unbh not needed*/);
+        RFALSE( removed <= 0 || removed > tail_len,
+                "vs-5617: there was tail %d bytes, removed item length %d bytes",
+                tail_len, removed);
+        tail_len -= removed;
+        set_cpu_key_k_offset (&tail_key, cpu_key_k_offset (&tail_key) - removed);
+    }
+    reiserfs_warning (inode->i_sb, "indirect_to_direct_roll_back: indirect_to_direct conversion has been rolled back due to lack of disk space");
+    //mark_file_without_tail (inode);
+    mark_inode_dirty (inode);
+}
+
+
+/* (Truncate or cut entry) or delete object item. Returns < 0 on failure */
+int reiserfs_cut_from_item (struct reiserfs_transaction_handle *th, 
+                            struct path * p_s_path,
+                            struct cpu_key * p_s_item_key,
+                            struct inode * p_s_inode,
+                            struct page *page, 
+                            loff_t n_new_file_size)
+{
+    struct super_block * p_s_sb = p_s_inode->i_sb;
+    /* Every function which is going to call do_balance must first
+       create a tree_balance structure.  Then it must fill up this
+       structure by using the init_tb_struct and fix_nodes functions.
+       After that we can make tree balancing. */
+    struct tree_balance s_cut_balance;
+    struct item_head *p_le_ih;
+    int n_cut_size = 0,        /* Amount to be cut. */
+        n_ret_value = CARRY_ON,
+        n_removed = 0,     /* Number of the removed unformatted nodes. */
+        n_is_inode_locked = 0;
+    char                c_mode;            /* Mode of the balance. */
+    int retval2 = -1;
+    int quota_cut_bytes;
+    loff_t tail_pos = 0;
+
+    BUG_ON (!th->t_trans_id);
+    
+    init_tb_struct(th, &s_cut_balance, p_s_inode->i_sb, p_s_path, n_cut_size);
+
+
+    /* Repeat this loop until we either cut the item without needing
+       to balance, or we fix_nodes without schedule occurring */
+    while ( 1 ) {
+        /* Determine the balance mode, position of the first byte to
+           be cut, and size to be cut.  In case of the indirect item
+           free unformatted nodes which are pointed to by the cut
+           pointers. */
+      
+        c_mode = prepare_for_delete_or_cut(th, p_s_inode, p_s_path, p_s_item_key, &n_removed, 
+                                           &n_cut_size, n_new_file_size);
+        if ( c_mode == M_CONVERT )  {
+            /* convert last unformatted node to direct item or leave
+               tail in the unformatted node */
+            RFALSE( n_ret_value != CARRY_ON, "PAP-5570: can not convert twice");
+
+            n_ret_value = maybe_indirect_to_direct (th, p_s_inode, page, p_s_path, p_s_item_key,
+                                                    n_new_file_size, &c_mode);
+            if ( c_mode == M_SKIP_BALANCING )
+                /* tail has been left in the unformatted node */
+                return n_ret_value;
+
+            n_is_inode_locked = 1;
+          
+            /* removing of last unformatted node will change value we
+               have to return to truncate. Save it */
+            retval2 = n_ret_value;
+            /*retval2 = p_s_sb->s_blocksize - (n_new_file_size & (p_s_sb->s_blocksize - 1));*/
+          
+            /* So, we have performed the first part of the conversion:
+               inserting the new direct item.  Now we are removing the
+               last unformatted node pointer. Set key to search for
+               it. */
+            set_cpu_key_k_type (p_s_item_key, TYPE_INDIRECT);
+            p_s_item_key->key_length = 4;
+            n_new_file_size -= (n_new_file_size & (p_s_sb->s_blocksize - 1));
+            tail_pos = n_new_file_size;
+            set_cpu_key_k_offset (p_s_item_key, n_new_file_size + 1);
+            if ( search_for_position_by_key(p_s_sb, p_s_item_key, p_s_path) == POSITION_NOT_FOUND ){
+                print_block (PATH_PLAST_BUFFER (p_s_path), 3, PATH_LAST_POSITION (p_s_path) - 1, PATH_LAST_POSITION (p_s_path) + 1);
+                reiserfs_panic(p_s_sb, "PAP-5580: reiserfs_cut_from_item: item to convert does not exist (%K)", p_s_item_key);
+            }
+            continue;
+        }
+        if (n_cut_size == 0) {
+            pathrelse (p_s_path);
+            return 0;
+        }
+
+        s_cut_balance.insert_size[0] = n_cut_size;
+        
+        n_ret_value = fix_nodes(c_mode, &s_cut_balance, NULL, NULL);
+        if ( n_ret_value != REPEAT_SEARCH )
+            break;
+        
+        PROC_INFO_INC( p_s_sb, cut_from_item_restarted );
+
+        n_ret_value = search_for_position_by_key(p_s_sb, p_s_item_key, p_s_path);
+        if (n_ret_value == POSITION_FOUND)
+            continue;
+
+        reiserfs_warning (p_s_sb, "PAP-5610: reiserfs_cut_from_item: item %K not found", p_s_item_key);
+        unfix_nodes (&s_cut_balance);
+        return (n_ret_value == IO_ERROR) ? -EIO : -ENOENT;
+    } /* while */
+  
+    // check fix_nodes results (IO_ERROR or NO_DISK_SPACE)
+    if ( n_ret_value != CARRY_ON ) {
+        if ( n_is_inode_locked ) {
+            // FIXME: this seems to be not needed: we are always able
+            // to cut item
+            indirect_to_direct_roll_back (th, p_s_inode, p_s_path);
+        }
+        if (n_ret_value == NO_DISK_SPACE)
+            reiserfs_warning (p_s_sb, "NO_DISK_SPACE");
+        unfix_nodes (&s_cut_balance);
+        return -EIO;
+    }
+
+    /* go ahead and perform balancing */
+    
+    RFALSE( c_mode == M_PASTE || c_mode == M_INSERT, "invalid mode");
+
+    /* Calculate number of bytes that need to be cut from the item. */
+    quota_cut_bytes = ( c_mode == M_DELETE ) ? ih_item_len(get_ih(p_s_path)) : -s_cut_balance.insert_size[0];
+    if (retval2 == -1)
+        n_ret_value = calc_deleted_bytes_number(&s_cut_balance, c_mode);
+    else
+        n_ret_value = retval2;
+
+
+    /* For direct items, we only change the quota when deleting the last
+    ** item.
+    */
+    p_le_ih = PATH_PITEM_HEAD (s_cut_balance.tb_path);
+    if (!S_ISLNK (p_s_inode->i_mode) && is_direct_le_ih(p_le_ih)) {
+        if (c_mode == M_DELETE &&
+           (le_ih_k_offset (p_le_ih) & (p_s_sb->s_blocksize - 1)) == 1 ) {
+            // FIXME: this is to keep 3.5 happy
+            REISERFS_I(p_s_inode)->i_first_direct_byte = U32_MAX;
+            quota_cut_bytes = p_s_sb->s_blocksize + UNFM_P_SIZE ;
+        } else {
+            quota_cut_bytes = 0 ;
+        }
+    }
+#ifdef CONFIG_REISERFS_CHECK
+    if (n_is_inode_locked) {
+        struct item_head * le_ih = PATH_PITEM_HEAD (s_cut_balance.tb_path);
+        /* we are going to complete indirect2direct conversion. Make
+           sure, that we exactly remove last unformatted node pointer
+           of the item */
+        if (!is_indirect_le_ih (le_ih))
+            reiserfs_panic (p_s_sb, "vs-5652: reiserfs_cut_from_item: "
+                            "item must be indirect %h", le_ih);
+
+        if (c_mode == M_DELETE && ih_item_len(le_ih) != UNFM_P_SIZE)
+            reiserfs_panic (p_s_sb, "vs-5653: reiserfs_cut_from_item: "
+                            "completing indirect2direct conversion indirect item %h "
+                            "being deleted must be of 4 byte long", le_ih);
+
+        if (c_mode == M_CUT && s_cut_balance.insert_size[0] != -UNFM_P_SIZE) {
+            reiserfs_panic (p_s_sb, "vs-5654: reiserfs_cut_from_item: "
+                            "can not complete indirect2direct conversion of %h (CUT, insert_size==%d)",
+                            le_ih, s_cut_balance.insert_size[0]);
+        }
+        /* it would be useful to make sure, that right neighboring
+           item is direct item of this file */
+    }
+#endif
+    
+    do_balance(&s_cut_balance, NULL, NULL, c_mode);
+    if ( n_is_inode_locked ) {
+        /* we've done an indirect->direct conversion.  when the data block
+        ** was freed, it was removed from the list of blocks that must
+        ** be flushed before the transaction commits, make sure to
+        ** unmap and invalidate it
+        */
+        unmap_buffers(page, tail_pos);
+        REISERFS_I(p_s_inode)->i_flags &= ~i_pack_on_close_mask ;
+    }
+#ifdef REISERQUOTA_DEBUG
+    reiserfs_debug (p_s_inode->i_sb, REISERFS_DEBUG_CODE, "reiserquota cut_from_item(): freeing %u id=%u type=%c", quota_cut_bytes, p_s_inode->i_uid, '?');
+#endif
+    DQUOT_FREE_SPACE_NODIRTY(p_s_inode, quota_cut_bytes);
+    return n_ret_value;
+}
+
+static void truncate_directory (struct reiserfs_transaction_handle *th, struct inode * inode)
+{
+    BUG_ON (!th->t_trans_id);
+    if (inode->i_nlink)
+        reiserfs_warning (inode->i_sb,
+                          "vs-5655: truncate_directory: link count != 0");
+
+    set_le_key_k_offset (KEY_FORMAT_3_5, INODE_PKEY (inode), DOT_OFFSET);
+    set_le_key_k_type (KEY_FORMAT_3_5, INODE_PKEY (inode), TYPE_DIRENTRY);
+    reiserfs_delete_solid_item (th, inode, INODE_PKEY (inode));
+    reiserfs_update_sd(th, inode) ;
+    set_le_key_k_offset (KEY_FORMAT_3_5, INODE_PKEY (inode), SD_OFFSET);
+    set_le_key_k_type (KEY_FORMAT_3_5, INODE_PKEY (inode), TYPE_STAT_DATA);    
+}
+
+
+
+
+/* Truncate file to the new size. Note, this must be called with a transaction
+   already started */
+int reiserfs_do_truncate (struct reiserfs_transaction_handle *th,
+                           struct  inode * p_s_inode, /* ->i_size contains new
+                                                         size */
+                           struct page *page, /* up to date for last block */
+                           int update_timestamps  /* when it is called by
+                                                     file_release to convert
+                                                     the tail - no timestamps
+                                                     should be updated */
+    ) {
+    INITIALIZE_PATH (s_search_path);       /* Path to the current object item. */
+    struct item_head    * p_le_ih;         /* Pointer to an item header. */
+    struct cpu_key      s_item_key;     /* Key to search for a previous file item. */
+    loff_t         n_file_size,    /* Old file size. */
+        n_new_file_size;/* New file size. */
+    int                   n_deleted;      /* Number of deleted or truncated bytes. */
+    int retval;
+    int err = 0;
+
+    BUG_ON (!th->t_trans_id);
+    if ( ! (S_ISREG(p_s_inode->i_mode) || S_ISDIR(p_s_inode->i_mode) || S_ISLNK(p_s_inode->i_mode)) )
+        return 0;
+
+    if (S_ISDIR(p_s_inode->i_mode)) {
+        // deletion of directory - no need to update timestamps
+        truncate_directory (th, p_s_inode);
+        return 0;
+    }
+
+    /* Get new file size. */
+    n_new_file_size = p_s_inode->i_size;
+
+    // FIXME: note, that key type is unimportant here
+    make_cpu_key (&s_item_key, p_s_inode, max_reiserfs_offset (p_s_inode), TYPE_DIRECT, 3);
+
+    retval = search_for_position_by_key(p_s_inode->i_sb, &s_item_key, &s_search_path);
+    if (retval == IO_ERROR) {
+        reiserfs_warning (p_s_inode->i_sb, "vs-5657: reiserfs_do_truncate: "
+                          "i/o failure occurred trying to truncate %K", &s_item_key);
+        err = -EIO;
+        goto out;
+    }
+    if (retval == POSITION_FOUND || retval == FILE_NOT_FOUND) {
+        reiserfs_warning (p_s_inode->i_sb, "PAP-5660: reiserfs_do_truncate: "
+                          "wrong result %d of search for %K", retval, &s_item_key);
+
+        err = -EIO;
+        goto out;
+    }
+
+    s_search_path.pos_in_item --;
+
+    /* Get real file size (total length of all file items) */
+    p_le_ih = PATH_PITEM_HEAD(&s_search_path);
+    if ( is_statdata_le_ih (p_le_ih) )
+        n_file_size = 0;
+    else {
+        loff_t offset = le_ih_k_offset (p_le_ih);
+        int bytes = op_bytes_number (p_le_ih,p_s_inode->i_sb->s_blocksize);
+
+        /* this may mismatch with real file size: if last direct item
+           had no padding zeros and last unformatted node had no free
+           space, this file would have this file size */
+        n_file_size = offset + bytes - 1;
+    }
+    /*
+     * are we doing a full truncate or delete, if so
+     * kick in the reada code
+     */
+    if (n_new_file_size == 0)
+        s_search_path.reada = PATH_READA | PATH_READA_BACK;
+
+    if ( n_file_size == 0 || n_file_size < n_new_file_size ) {
+        goto update_and_out ;
+    }
+
+    /* Update key to search for the last file item. */
+    set_cpu_key_k_offset (&s_item_key, n_file_size);
+
+    do  {
+        /* Cut or delete file item. */
+        n_deleted = reiserfs_cut_from_item(th, &s_search_path, &s_item_key, p_s_inode,  page, n_new_file_size);
+        if (n_deleted < 0) {
+            reiserfs_warning (p_s_inode->i_sb, "vs-5665: reiserfs_do_truncate: reiserfs_cut_from_item failed");
+            reiserfs_check_path(&s_search_path) ;
+            return 0;
+        }
+
+        RFALSE( n_deleted > n_file_size,
+                "PAP-5670: reiserfs_cut_from_item: too many bytes deleted: deleted %d, file_size %lu, item_key %K",
+                n_deleted, n_file_size, &s_item_key);
+
+        /* Change key to search the last file item. */
+        n_file_size -= n_deleted;
+
+        set_cpu_key_k_offset (&s_item_key, n_file_size);
+
+        /* While there are bytes to truncate and previous file item is presented in the tree. */
+
+        /*
+        ** This loop could take a really long time, and could log 
+        ** many more blocks than a transaction can hold.  So, we do a polite
+        ** journal end here, and if the transaction needs ending, we make
+        ** sure the file is consistent before ending the current trans
+        ** and starting a new one
+        */
+        if (journal_transaction_should_end(th, th->t_blocks_allocated)) {
+          int orig_len_alloc = th->t_blocks_allocated ;
+          decrement_counters_in_path(&s_search_path) ;
+
+          if (update_timestamps) {
+              p_s_inode->i_mtime = p_s_inode->i_ctime = CURRENT_TIME_SEC;
+          } 
+          reiserfs_update_sd(th, p_s_inode) ;
+
+          err = journal_end(th, p_s_inode->i_sb, orig_len_alloc) ;
+          if (err)
+            goto out;
+          err = journal_begin (th, p_s_inode->i_sb,
+                               JOURNAL_PER_BALANCE_CNT * 6);
+          if (err)
+            goto out;
+          reiserfs_update_inode_transaction(p_s_inode) ;
+        }
+    } while ( n_file_size > ROUND_UP (n_new_file_size) &&
+              search_for_position_by_key(p_s_inode->i_sb, &s_item_key, &s_search_path) == POSITION_FOUND )  ;
+
+    RFALSE( n_file_size > ROUND_UP (n_new_file_size),
+            "PAP-5680: truncate did not finish: new_file_size %Ld, current %Ld, oid %d",
+            n_new_file_size, n_file_size, s_item_key.on_disk_key.k_objectid);
+
+update_and_out:
+    if (update_timestamps) {
+        // this is truncate, not file closing
+            p_s_inode->i_mtime = p_s_inode->i_ctime = CURRENT_TIME_SEC;
+    }
+    reiserfs_update_sd (th, p_s_inode);
+
+out:
+    pathrelse(&s_search_path) ;
+    return err;
+}
+
+
+#ifdef CONFIG_REISERFS_CHECK
+// this makes sure, that we __append__, not overwrite or add holes
+static void check_research_for_paste (struct path * path, 
+                                      const struct cpu_key * p_s_key)
+{
+    struct item_head * found_ih = get_ih (path);
+    
+    if (is_direct_le_ih (found_ih)) {
+        if (le_ih_k_offset (found_ih) + op_bytes_number (found_ih, get_last_bh (path)->b_size) !=
+            cpu_key_k_offset (p_s_key) ||
+            op_bytes_number (found_ih, get_last_bh (path)->b_size) != pos_in_item (path))
+            reiserfs_panic (NULL, "PAP-5720: check_research_for_paste: "
+                            "found direct item %h or position (%d) does not match to key %K",
+                            found_ih, pos_in_item (path), p_s_key);
+    }
+    if (is_indirect_le_ih (found_ih)) {
+        if (le_ih_k_offset (found_ih) + op_bytes_number (found_ih, get_last_bh (path)->b_size) != cpu_key_k_offset (p_s_key) || 
+            I_UNFM_NUM (found_ih) != pos_in_item (path) ||
+            get_ih_free_space (found_ih) != 0)
+            reiserfs_panic (NULL, "PAP-5730: check_research_for_paste: "
+                            "found indirect item (%h) or position (%d) does not match to key (%K)",
+                            found_ih, pos_in_item (path), p_s_key);
+    }
+}
+#endif /* config reiserfs check */
+
+
+/* Paste bytes to the existing item. Returns bytes number pasted into the item. */
+int reiserfs_paste_into_item (struct reiserfs_transaction_handle *th, 
+                              struct path         * p_s_search_path,    /* Path to the pasted item.          */
+                              const struct cpu_key      * p_s_key,              /* Key to search for the needed item.*/
+                              struct inode        * inode,              /* Inode item belongs to */
+                              const char          * p_c_body,           /* Pointer to the bytes to paste.    */
+                              int                   n_pasted_size)      /* Size of pasted bytes.             */
+{
+    struct tree_balance s_paste_balance;
+    int                 retval;
+    int                 fs_gen;
+
+    BUG_ON (!th->t_trans_id);
+
+    fs_gen = get_generation(inode->i_sb) ;
+
+#ifdef REISERQUOTA_DEBUG
+    reiserfs_debug (inode->i_sb, REISERFS_DEBUG_CODE, "reiserquota paste_into_item(): allocating %u id=%u type=%c", n_pasted_size, inode->i_uid, key2type(&(p_s_key->on_disk_key)));
+#endif
+
+    if (DQUOT_ALLOC_SPACE_NODIRTY(inode, n_pasted_size)) {
+        pathrelse(p_s_search_path);
+        return -EDQUOT;
+    }
+    init_tb_struct(th, &s_paste_balance, th->t_super, p_s_search_path, n_pasted_size);
+#ifdef DISPLACE_NEW_PACKING_LOCALITIES
+    s_paste_balance.key = p_s_key->on_disk_key;
+#endif
+
+    /* DQUOT_* can schedule, must check before the fix_nodes */
+    if (fs_changed(fs_gen, inode->i_sb)) {
+        goto search_again;
+    }
+
+    while ((retval = fix_nodes(M_PASTE, &s_paste_balance, NULL, p_c_body)) ==
+REPEAT_SEARCH ) {
+search_again:
+        /* file system changed while we were in the fix_nodes */
+        PROC_INFO_INC( th -> t_super, paste_into_item_restarted );
+        retval = search_for_position_by_key (th->t_super, p_s_key, p_s_search_path);
+        if (retval == IO_ERROR) {
+            retval = -EIO ;
+            goto error_out ;
+        }
+        if (retval == POSITION_FOUND) {
+            reiserfs_warning (inode->i_sb, "PAP-5710: reiserfs_paste_into_item: entry or pasted byte (%K) exists", p_s_key);
+            retval = -EEXIST ;
+            goto error_out ;
+        }
+        
+#ifdef CONFIG_REISERFS_CHECK
+        check_research_for_paste (p_s_search_path, p_s_key);
+#endif
+    }
+
+    /* Perform balancing after all resources are collected by fix_nodes, and
+       accessing them will not risk triggering schedule. */
+    if ( retval == CARRY_ON ) {
+        do_balance(&s_paste_balance, NULL/*ih*/, p_c_body, M_PASTE);
+        return 0;
+    }
+    retval = (retval == NO_DISK_SPACE) ? -ENOSPC : -EIO;
+error_out:
+    /* this also releases the path */
+    unfix_nodes(&s_paste_balance);
+#ifdef REISERQUOTA_DEBUG
+    reiserfs_debug (inode->i_sb, REISERFS_DEBUG_CODE, "reiserquota paste_into_item(): freeing %u id=%u type=%c", n_pasted_size, inode->i_uid, key2type(&(p_s_key->on_disk_key)));
+#endif
+    DQUOT_FREE_SPACE_NODIRTY(inode, n_pasted_size);
+    return retval ;
+}
+
+
+/* Insert new item into the buffer at the path. */
+int reiserfs_insert_item(struct reiserfs_transaction_handle *th, 
+                         struct path         *  p_s_path,         /* Path to the inserteded item.         */
+                         const struct cpu_key      * key,
+                         struct item_head    *  p_s_ih,           /* Pointer to the item header to insert.*/
+                         struct inode        * inode,
+                         const char          *  p_c_body)         /* Pointer to the bytes to insert.      */
+{
+    struct tree_balance s_ins_balance;
+    int                 retval;
+    int fs_gen = 0 ;
+    int quota_bytes = 0 ;
+
+    BUG_ON (!th->t_trans_id);
+
+    if (inode) {      /* Do we count quotas for item? */
+        fs_gen = get_generation(inode->i_sb);
+        quota_bytes = ih_item_len(p_s_ih);
+
+        /* hack so the quota code doesn't have to guess if the file has
+         ** a tail, links are always tails, so there's no guessing needed
+         */
+        if (!S_ISLNK (inode->i_mode) && is_direct_le_ih(p_s_ih)) {
+            quota_bytes = inode->i_sb->s_blocksize + UNFM_P_SIZE ;
+        }
+#ifdef REISERQUOTA_DEBUG
+        reiserfs_debug (inode->i_sb, REISERFS_DEBUG_CODE, "reiserquota insert_item(): allocating %u id=%u type=%c", quota_bytes, inode->i_uid, head2type(p_s_ih));
+#endif
+        /* We can't dirty inode here. It would be immediately written but
+         * appropriate stat item isn't inserted yet... */
+        if (DQUOT_ALLOC_SPACE_NODIRTY(inode, quota_bytes)) {
+            pathrelse(p_s_path);
+            return -EDQUOT;
+        }
+    }
+    init_tb_struct(th, &s_ins_balance, th->t_super, p_s_path, IH_SIZE + ih_item_len(p_s_ih));
+#ifdef DISPLACE_NEW_PACKING_LOCALITIES
+    s_ins_balance.key = key->on_disk_key;
+#endif
+    /* DQUOT_* can schedule, must check to be sure calling fix_nodes is safe */
+    if (inode && fs_changed(fs_gen, inode->i_sb)) {
+        goto search_again;
+    }
+
+    while ( (retval = fix_nodes(M_INSERT, &s_ins_balance, p_s_ih, p_c_body)) == REPEAT_SEARCH) {
+search_again:
+        /* file system changed while we were in the fix_nodes */
+        PROC_INFO_INC( th -> t_super, insert_item_restarted );
+        retval = search_item (th->t_super, key, p_s_path);
+        if (retval == IO_ERROR) {
+            retval = -EIO;
+            goto error_out ;
+        }
+        if (retval == ITEM_FOUND) {
+            reiserfs_warning (th->t_super, "PAP-5760: reiserfs_insert_item: "
+                              "key %K already exists in the tree", key);
+            retval = -EEXIST ;
+            goto error_out; 
+        }
+    }
+
+    /* make balancing after all resources will be collected at a time */ 
+    if ( retval == CARRY_ON ) {
+        do_balance (&s_ins_balance, p_s_ih, p_c_body, M_INSERT);
+        return 0;
+    }
+
+    retval = (retval == NO_DISK_SPACE) ? -ENOSPC : -EIO;
+error_out:
+    /* also releases the path */
+    unfix_nodes(&s_ins_balance);
+#ifdef REISERQUOTA_DEBUG
+    reiserfs_debug (th->t_super, REISERFS_DEBUG_CODE, "reiserquota insert_item(): freeing %u id=%u type=%c", quota_bytes, inode->i_uid, head2type(p_s_ih));
+#endif
+    if (inode)
+        DQUOT_FREE_SPACE_NODIRTY(inode, quota_bytes) ;
+    return retval; 
+}
+
+
+
+