patch-2.4.1 linux/fs/reiserfs/do_balan.c

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diff -u --recursive --new-file v2.4.0/linux/fs/reiserfs/do_balan.c linux/fs/reiserfs/do_balan.c
@@ -0,0 +1,2043 @@
+/*
+ * Copyright 2000 by Hans Reiser, licensing governed by reiserfs/README
+ */
+
+/* Now we have all buffers that must be used in balancing of the tree 	*/
+/* Further calculations can not cause schedule(), and thus the buffer 	*/
+/* tree will be stable until the balancing will be finished 		*/
+/* balance the tree according to the analysis made before,		*/
+/* and using buffers obtained after all above.				*/
+
+
+/**
+ ** balance_leaf_when_delete
+ ** balance_leaf
+ ** do_balance
+ **
+ **/
+
+#ifdef __KERNEL__
+
+#include <linux/config.h>
+#include <asm/uaccess.h>
+#include <linux/sched.h>
+#include <linux/reiserfs_fs.h>
+
+#else
+
+#include "nokernel.h"
+
+#endif
+
+
+#ifdef CONFIG_REISERFS_CHECK
+
+struct tree_balance * cur_tb = NULL; /* detects whether more than one
+                                        copy of tb exists as a means
+                                        of checking whether schedule
+                                        is interrupting do_balance */
+#endif
+
+
+inline void do_balance_mark_leaf_dirty (struct tree_balance * tb, 
+					struct buffer_head * bh, int flag)
+{
+    if (reiserfs_dont_log(tb->tb_sb)) {
+	if (!test_and_set_bit(BH_Dirty, &bh->b_state)) {
+	    __mark_buffer_dirty(bh) ;
+	    tb->need_balance_dirty = 1;
+	}
+    } else {
+	int windex = push_journal_writer("do_balance") ;
+	journal_mark_dirty(tb->transaction_handle, tb->transaction_handle->t_super, bh) ;
+	pop_journal_writer(windex) ;
+    }
+}
+
+#define do_balance_mark_internal_dirty do_balance_mark_leaf_dirty
+#define do_balance_mark_sb_dirty do_balance_mark_leaf_dirty
+
+
+/* summary: 
+ if deleting something ( tb->insert_size[0] < 0 )
+   return(balance_leaf_when_delete()); (flag d handled here)
+ else
+   if lnum is larger than 0 we put items into the left node
+   if rnum is larger than 0 we put items into the right node
+   if snum1 is larger than 0 we put items into the new node s1
+   if snum2 is larger than 0 we put items into the new node s2 
+Note that all *num* count new items being created.
+
+It would be easier to read balance_leaf() if each of these summary
+lines was a separate procedure rather than being inlined.  I think
+that there are many passages here and in balance_leaf_when_delete() in
+which two calls to one procedure can replace two passages, and it
+might save cache space and improve software maintenance costs to do so.  
+
+Vladimir made the perceptive comment that we should offload most of
+the decision making in this function into fix_nodes/check_balance, and
+then create some sort of structure in tb that says what actions should
+be performed by do_balance.
+
+-Hans */
+
+
+
+/* Balance leaf node in case of delete or cut: insert_size[0] < 0
+ *
+ * lnum, rnum can have values >= -1
+ *	-1 means that the neighbor must be joined with S
+ *	 0 means that nothing should be done with the neighbor
+ *	>0 means to shift entirely or partly the specified number of items to the neighbor
+ */
+static int balance_leaf_when_delete (struct tree_balance * tb, int flag)
+{
+    struct buffer_head * tbS0 = PATH_PLAST_BUFFER (tb->tb_path);
+    int item_pos = PATH_LAST_POSITION (tb->tb_path);
+    int pos_in_item = tb->tb_path->pos_in_item;
+    struct buffer_info bi;
+    int n;
+    struct item_head * ih;
+
+#ifdef CONFIG_REISERFS_CHECK
+    if ( tb->FR[0] && B_LEVEL (tb->FR[0]) != DISK_LEAF_NODE_LEVEL + 1)
+	reiserfs_panic (tb->tb_sb,
+			"vs- 12000: balance_leaf_when_delete:level: wrong FR %z\n", tb->FR[0]);
+    if ( tb->blknum[0] > 1 )
+	reiserfs_panic (tb->tb_sb,
+			"PAP-12005: balance_leaf_when_delete: "
+			"tb->blknum == %d, can not be > 1", tb->blknum[0]);
+	
+    if ( ! tb->blknum[0] && ! PATH_H_PPARENT(tb->tb_path, 0))
+	reiserfs_panic (tb->tb_sb, "PAP-12010: balance_leaf_when_delete: tree can not be empty");
+#endif
+
+    ih = B_N_PITEM_HEAD (tbS0, item_pos);
+
+    /* Delete or truncate the item */
+
+    switch (flag) {
+    case M_DELETE:   /* delete item in S[0] */
+
+#ifdef CONFIG_REISERFS_CHECK
+	if (le16_to_cpu (ih->ih_item_len) + IH_SIZE != -tb->insert_size [0])
+	    reiserfs_panic (tb->tb_sb, "vs-12013: balance_leaf_when_delete: "
+			    "mode Delete, insert size %d, ih to be deleted %h", ih);
+
+#if 0 /* rigth delim key not supported */
+	if ( ! item_pos && (! tb->L[0] || COMP_KEYS(B_PRIGHT_DELIM_KEY(tb->L[0]), B_N_PKEY(tbS0, 0))) ) {
+	    print_cur_tb ("12015");
+	    reiserfs_panic (tb->tb_sb, "PAP-12015: balance_leaf_when_delete: L0's rkey does not match to 1st key of S0: "
+			    "rkey in L %k, first key in S0 %k, rkey in CFL %k",
+			    tb->L[0] ? B_PRIGHT_DELIM_KEY(tb->L[0]) : 0, 
+			    B_N_PKEY(tbS0, 0),
+			    tb->CFL[0] ? B_N_PDELIM_KEY(tb->CFL[0],tb->lkey[0]) : 0);
+	}
+#endif
+
+#endif
+
+	bi.tb = tb;
+	bi.bi_bh = tbS0;
+	bi.bi_parent = PATH_H_PPARENT (tb->tb_path, 0);
+	bi.bi_position = PATH_H_POSITION (tb->tb_path, 1);
+	leaf_delete_items (&bi, 0, item_pos, 1, -1);
+
+	if ( ! item_pos && tb->CFL[0] ) {
+	    if ( B_NR_ITEMS(tbS0) ) {
+		replace_key(tb, tb->CFL[0],tb->lkey[0],tbS0,0);
+#if 0 /* right delim key support */
+		copy_key(B_PRIGHT_DELIM_KEY(tb->L[0]), B_N_PKEY(tbS0, 0));
+		reiserfs_mark_buffer_dirty (tb->L[0], 0);
+#endif
+	    }
+	    else {
+		if ( ! PATH_H_POSITION (tb->tb_path, 1) )
+		    replace_key(tb, tb->CFL[0],tb->lkey[0],PATH_H_PPARENT(tb->tb_path, 0),0);
+#if 0 /* right delim key support */
+		copy_key(B_PRIGHT_DELIM_KEY(tb->L[0]), B_PRIGHT_DELIM_KEY(tbS0));
+		reiserfs_mark_buffer_dirty (tb->L[0], 0);
+#endif
+	    }
+	} 
+
+#ifdef CONFIG_REISERFS_CHECK
+#if 0
+	if (! item_pos && (!tb->CFL[0] || !tb->L[0]))
+#endif
+	    if (! item_pos && !tb->CFL[0])
+		reiserfs_panic (tb->tb_sb, "PAP-12020: balance_leaf_when_delete: tb->CFL[0]==%p, tb->L[0]==%p", tb->CFL[0], tb->L[0]);
+#endif
+    
+	break;
+
+    case M_CUT: {  /* cut item in S[0] */
+	bi.tb = tb;
+	bi.bi_bh = tbS0;
+	bi.bi_parent = PATH_H_PPARENT (tb->tb_path, 0);
+	bi.bi_position = PATH_H_POSITION (tb->tb_path, 1);
+	if (is_direntry_le_ih (ih)) {
+
+#ifdef CONFIG_REISERFS_CHECK
+#if 0 /* right delim key support */
+	    if ( ! item_pos && ! pos_in_item && (! tb->L[0] || COMP_KEYS(B_PRIGHT_DELIM_KEY(tb->L[0]), 
+									 B_N_PKEY(tbS0, 0))) )
+		reiserfs_panic(tb->tb_sb, "PAP-12025: balance_leaf_when_delete: illegal right delimiting key");
+#endif
+#endif
+
+	    /* UFS unlink semantics are such that you can only delete one directory entry at a time. */
+	    /* when we cut a directory tb->insert_size[0] means number of entries to be cut (always 1) */
+	    tb->insert_size[0] = -1;
+	    leaf_cut_from_buffer (&bi, item_pos, pos_in_item, -tb->insert_size[0]);
+
+#ifdef CONFIG_REISERFS_CHECK
+	    if (! item_pos && ! pos_in_item && ! tb->CFL[0])
+		reiserfs_panic (tb->tb_sb, "PAP-12030: balance_leaf_when_delete: can not change delimiting key. CFL[0]=%p", tb->CFL[0]);
+#endif /* CONFIG_REISERFS_CHECK */
+
+	    if ( ! item_pos && ! pos_in_item && tb->CFL[0] ) {
+		replace_key(tb, tb->CFL[0],tb->lkey[0],tbS0,0);
+#if 0/* right delim key support */
+		copy_key(B_PRIGHT_DELIM_KEY(tb->L[0]), B_N_PKEY(tbS0, 0));
+		reiserfs_mark_buffer_dirty (tb->L[0], 0);
+#endif
+	    }
+	} else {
+	    leaf_cut_from_buffer (&bi, item_pos, pos_in_item, -tb->insert_size[0]);
+
+#ifdef CONFIG_REISERFS_CHECK
+	    if (! ih->ih_item_len)
+		reiserfs_panic (tb->tb_sb, "PAP-12035: balance_leaf_when_delete: cut must leave non-zero dynamic length of item");
+#endif /* CONFIG_REISERFS_CHECK */
+	}
+	break;
+    }
+
+    default:
+	print_cur_tb ("12040");
+	reiserfs_panic (tb->tb_sb, "PAP-12040: balance_leaf_when_delete: unexpectable mode: %s(%d)",
+			(flag == M_PASTE) ? "PASTE" : ((flag == M_INSERT) ? "INSERT" : "UNKNOWN"), flag);
+    }
+
+    /* the rule is that no shifting occurs unless by shifting a node can be freed */
+    n = B_NR_ITEMS(tbS0);
+    if ( tb->lnum[0] )     /* L[0] takes part in balancing */
+    {
+	if ( tb->lnum[0] == -1 )    /* L[0] must be joined with S[0] */
+	{
+	    if ( tb->rnum[0] == -1 )    /* R[0] must be also joined with S[0] */
+	    {			
+		if ( tb->FR[0] == PATH_H_PPARENT(tb->tb_path, 0) )
+		{
+		    /* all contents of all the 3 buffers will be in L[0] */
+		    if ( PATH_H_POSITION (tb->tb_path, 1) == 0 && 1 < B_NR_ITEMS(tb->FR[0]) )
+			replace_key(tb, tb->CFL[0],tb->lkey[0],tb->FR[0],1);
+
+		    /* update right_delimiting_key field */
+#if 0
+		    copy_key (B_PRIGHT_DELIM_KEY (tb->L[0]), B_PRIGHT_DELIM_KEY (tb->R[0]));
+#endif
+		    leaf_move_items (LEAF_FROM_S_TO_L, tb, n, -1, 0);
+		    leaf_move_items (LEAF_FROM_R_TO_L, tb, B_NR_ITEMS(tb->R[0]), -1, 0);
+
+#if 0/*preserve list*/
+		    preserve_invalidate(tb, tbS0, tb->L[0]); 
+		    preserve_invalidate(tb, tb->R[0], tb->L[0]);
+#endif
+		    reiserfs_invalidate_buffer (tb, tbS0);
+		    reiserfs_invalidate_buffer (tb, tb->R[0]);
+
+		    return 0;
+		}
+		/* all contents of all the 3 buffers will be in R[0] */
+		leaf_move_items (LEAF_FROM_S_TO_R, tb, n, -1, 0);
+		leaf_move_items (LEAF_FROM_L_TO_R, tb, B_NR_ITEMS(tb->L[0]), -1, 0);
+
+		/* right_delimiting_key is correct in R[0] */
+		replace_key(tb, tb->CFR[0],tb->rkey[0],tb->R[0],0);
+
+#if 0
+		/* mark tb->R[0] as suspected recipient */
+		preserve_invalidate(tb,tbS0, tb->R[0]);
+		preserve_invalidate(tb,tb->L[0], tb->R[0]); 
+#endif
+		reiserfs_invalidate_buffer (tb, tbS0);
+		reiserfs_invalidate_buffer (tb, tb->L[0]);
+
+		return -1;
+	    }
+
+#ifdef CONFIG_REISERFS_CHECK
+	    if ( tb->rnum[0] != 0 )
+		reiserfs_panic (tb->tb_sb, "PAP-12045: balance_leaf_when_delete: "
+				"rnum must be 0 (%d)", tb->rnum[0]);
+#endif /* CONFIG_REISERFS_CHECK */
+
+	    /* all contents of L[0] and S[0] will be in L[0] */
+	    leaf_shift_left(tb, n, -1);
+
+#if 0/*preserve list*/
+	    preserve_invalidate(tb, tbS0, tb->L[0]);  /* preserved, shifting */
+#endif
+	    reiserfs_invalidate_buffer (tb, tbS0);
+
+	    return 0;
+	}
+	/* a part of contents of S[0] will be in L[0] and the rest part of S[0] will be in R[0] */
+
+#ifdef CONFIG_REISERFS_CHECK
+	if (( tb->lnum[0] + tb->rnum[0] < n ) || ( tb->lnum[0] + tb->rnum[0] > n+1 ))
+	    reiserfs_panic (tb->tb_sb, "PAP-12050: balance_leaf_when_delete: "
+			    "rnum(%d) and lnum(%d) and item number in S[0] are not consistent",
+			    tb->rnum[0], tb->lnum[0], n);
+
+	if (( tb->lnum[0] + tb->rnum[0] == n ) && (tb->lbytes != -1 || tb->rbytes != -1))
+	    reiserfs_panic (tb->tb_sb, "PAP-12055: balance_leaf_when_delete: "
+			    "bad rbytes (%d)/lbytes (%d) parameters when items are not split", 
+			    tb->rbytes, tb->lbytes);
+	if (( tb->lnum[0] + tb->rnum[0] == n + 1 ) && (tb->lbytes < 1 || tb->rbytes != -1))
+	    reiserfs_panic (tb->tb_sb, "PAP-12060: balance_leaf_when_delete: "
+			    "bad rbytes (%d)/lbytes (%d) parameters when items are split", 
+			    tb->rbytes, tb->lbytes);
+#endif
+
+	leaf_shift_left (tb, tb->lnum[0], tb->lbytes);
+	leaf_shift_right(tb, tb->rnum[0], tb->rbytes);
+
+#if 0/*preserve list*/
+	preserve_invalidate (tb, tbS0, tb->L[0]);
+	mark_suspected_recipient (tb->tb_sb, tb->R[0]);
+#endif
+	reiserfs_invalidate_buffer (tb, tbS0);
+
+	return 0;
+    }
+
+    if ( tb->rnum[0] == -1 ) {
+	/* all contents of R[0] and S[0] will be in R[0] */
+	leaf_shift_right(tb, n, -1);
+#if 0/*preserve list*/
+	preserve_invalidate(tb, tbS0, tb->R[0]); 
+#endif
+	reiserfs_invalidate_buffer (tb, tbS0);
+	return 0;
+    }
+
+#ifdef CONFIG_REISERFS_CHECK
+    if ( tb->rnum[0] )
+	reiserfs_panic (tb->tb_sb, "PAP-12065: balance_leaf_when_delete: "
+			"bad rnum parameter must be 0 (%d)", tb->rnum[0]);
+#endif
+
+    return 0;
+}
+
+
+static int balance_leaf (struct tree_balance * tb,
+			 struct item_head * ih,		/* item header of inserted item (this is on little endian) */
+			 const char * body,		/* body  of inserted item or bytes to paste */
+			 int flag,			/* i - insert, d - delete, c - cut, p - paste
+							   (see comment to do_balance) */
+			 struct item_head * insert_key,  /* in our processing of one level we sometimes determine what
+							    must be inserted into the next higher level.  This insertion
+							    consists of a key or two keys and their corresponding
+							    pointers */
+			 struct buffer_head ** insert_ptr /* inserted node-ptrs for the next level */
+    )
+{
+    struct buffer_head * tbS0 = PATH_PLAST_BUFFER (tb->tb_path);
+#if 0/*preserve list*/
+    struct buffer_head * tbF0 = PATH_H_PPARENT (tb->tb_path, 0);
+    int S0_b_item_order = PATH_H_B_ITEM_ORDER (tb->tb_path, 0);
+#endif
+    int item_pos = PATH_LAST_POSITION (tb->tb_path);	/*  index into the array of item headers in S[0] 
+							    of the affected item */
+    struct buffer_info bi;
+    struct buffer_head *S_new[2];  /* new nodes allocated to hold what could not fit into S */
+    int snum[2];	    /* number of items that will be placed
+                               into S_new (includes partially shifted
+                               items) */
+    int sbytes[2];          /* if an item is partially shifted into S_new then 
+			       if it is a directory item 
+			       it is the number of entries from the item that are shifted into S_new
+			       else
+			       it is the number of bytes from the item that are shifted into S_new
+			    */
+    int n, i;
+    int ret_val;
+    int pos_in_item;
+    int zeros_num;
+
+#if 0
+    if (tb->insert_size [0] % 4) {
+	reiserfs_panic (tb->tb_sb, "balance_leaf: wrong insert_size %d", 
+			tb->insert_size [0]);
+    }
+#endif
+    /* Make balance in case insert_size[0] < 0 */
+    if ( tb->insert_size[0] < 0 )
+	return balance_leaf_when_delete (tb, flag);
+  
+    zeros_num = 0;
+    if (flag == M_INSERT && body == 0)
+	zeros_num = le16_to_cpu (ih->ih_item_len); 
+
+    pos_in_item = tb->tb_path->pos_in_item;
+    /* for indirect item pos_in_item is measured in unformatted node
+       pointers. Recalculate to bytes */
+    if (flag != M_INSERT && is_indirect_le_ih (B_N_PITEM_HEAD (tbS0, item_pos)))
+	pos_in_item *= UNFM_P_SIZE;
+
+    if ( tb->lnum[0] > 0 ) {
+	/* Shift lnum[0] items from S[0] to the left neighbor L[0] */
+	if ( item_pos < tb->lnum[0] ) {
+	    /* new item or it part falls to L[0], shift it too */
+	    n = B_NR_ITEMS(tb->L[0]);
+
+	    switch (flag) {
+	    case M_INSERT:   /* insert item into L[0] */
+
+		if ( item_pos == tb->lnum[0] - 1 && tb->lbytes != -1 ) {
+		    /* part of new item falls into L[0] */
+		    int new_item_len;
+		    int version;
+
+#ifdef CONFIG_REISERFS_CHECK
+		    if (!is_direct_le_ih (ih))
+			reiserfs_panic (tb->tb_sb, "PAP-12075: balance_leaf: " 
+					"only direct inserted item can be broken. %h", ih);
+#endif
+		    ret_val = leaf_shift_left (tb, tb->lnum[0]-1, -1);
+		    /* when reading the if conditions preceding the subsequent preserve_shifted
+		       lines understand that their goal is to determine if all that we are
+		       shifting is the new data being added */
+#if 0/*preserve list*/
+		    if (tb->lnum[0] - 1 > 0) {
+			preserve_shifted(tb, &(PATH_PLAST_BUFFER (tb->tb_path)), tbF0, S0_b_item_order, tb->L[0]);
+			tbS0 = PATH_PLAST_BUFFER (tb->tb_path);
+		    }
+#endif
+
+		    /* Calculate item length to insert to S[0] */
+		    new_item_len = le16_to_cpu (ih->ih_item_len) - tb->lbytes;
+		    /* Calculate and check item length to insert to L[0] */
+		    ih->ih_item_len -= new_item_len;
+
+#ifdef CONFIG_REISERFS_CHECK
+		    if ( (int)(ih->ih_item_len) <= 0 )
+			reiserfs_panic(tb->tb_sb, "PAP-12080: balance_leaf: "
+				       "there is nothing to insert into L[0]: ih_item_len=%d",
+				       (int)ih->ih_item_len);
+#endif
+
+		    /* Insert new item into L[0] */
+		    bi.tb = tb;
+		    bi.bi_bh = tb->L[0];
+		    bi.bi_parent = tb->FL[0];
+		    bi.bi_position = get_left_neighbor_position (tb, 0);
+		    leaf_insert_into_buf (&bi, n + item_pos - ret_val, ih, body,
+					  zeros_num > ih->ih_item_len ? ih->ih_item_len : zeros_num);
+
+		    version = ih_version (ih);
+
+		    /* Calculate key component, item length and body to insert into S[0] */
+		    set_le_key_k_offset (ih_version (ih), &(ih->ih_key),
+					 le_key_k_offset (ih_version (ih), &(ih->ih_key)) + tb->lbytes);
+		    ih->ih_item_len = cpu_to_le16 (new_item_len);
+		    if ( tb->lbytes >  zeros_num ) {
+			body += (tb->lbytes - zeros_num);
+			zeros_num = 0;
+		    }
+		    else
+			zeros_num -= tb->lbytes;
+
+#ifdef CONFIG_REISERFS_CHECK
+		    if ( (int)(ih->ih_item_len) <= 0 )
+			reiserfs_panic(tb->tb_sb, "PAP-12085: balance_leaf: "
+				       "there is nothing to insert into S[0]: ih_item_len=%d",
+				       (int)ih->ih_item_len);
+#endif
+		} else {
+		    /* new item in whole falls into L[0] */
+		    /* Shift lnum[0]-1 items to L[0] */
+		    ret_val = leaf_shift_left(tb, tb->lnum[0]-1, tb->lbytes);
+#if 0/*preserve list*/
+		    if (tb->lnum[0] > 1) {
+			preserve_shifted(tb, &(PATH_PLAST_BUFFER (tb->tb_path)), tbF0, S0_b_item_order, tb->L[0]);
+			tbS0 = PATH_PLAST_BUFFER (tb->tb_path);
+		    }
+#endif
+		    /* Insert new item into L[0] */
+		    bi.tb = tb;
+		    bi.bi_bh = tb->L[0];
+		    bi.bi_parent = tb->FL[0];
+		    bi.bi_position = get_left_neighbor_position (tb, 0);
+		    leaf_insert_into_buf (&bi, n + item_pos - ret_val, ih, body, zeros_num);
+#if 0/*preserve list*/
+		    if (tb->preserve_mode == PRESERVE_INDIRECT_TO_DIRECT){
+			mark_suspected_recipient (tb->tb_sb, bi.bi_bh);
+		    }
+#endif
+		    tb->insert_size[0] = 0;
+		    zeros_num = 0;
+		}
+		break;
+
+	    case M_PASTE:   /* append item in L[0] */
+
+		if ( item_pos == tb->lnum[0] - 1 && tb->lbytes != -1 ) {
+		    /* we must shift the part of the appended item */
+		    if ( is_direntry_le_ih (B_N_PITEM_HEAD (tbS0, item_pos))) {
+
+#ifdef CONFIG_REISERFS_CHECK
+			if ( zeros_num )
+			    reiserfs_panic(tb->tb_sb, "PAP-12090: balance_leaf: illegal parameter in case of a directory");
+#endif
+            
+			/* directory item */
+			if ( tb->lbytes > pos_in_item ) {
+			    /* new directory entry falls into L[0] */
+			    struct item_head * pasted;
+			    int l_pos_in_item = pos_in_item;
+							  
+			    /* Shift lnum[0] - 1 items in whole. Shift lbytes - 1 entries from given directory item */
+			    ret_val = leaf_shift_left(tb, tb->lnum[0], tb->lbytes - 1);
+#if 0/*preserve list*/
+			    preserve_shifted(tb, &(PATH_PLAST_BUFFER (tb->tb_path)), tbF0, S0_b_item_order, tb->L[0]);
+			    tbS0 = PATH_PLAST_BUFFER (tb->tb_path);
+#endif
+			    if ( ret_val && ! item_pos ) {
+				pasted =  B_N_PITEM_HEAD(tb->L[0],B_NR_ITEMS(tb->L[0])-1);
+				l_pos_in_item += I_ENTRY_COUNT(pasted) - (tb->lbytes-1);
+			    }
+
+			    /* Append given directory entry to directory item */
+			    bi.tb = tb;
+			    bi.bi_bh = tb->L[0];
+			    bi.bi_parent = tb->FL[0];
+			    bi.bi_position = get_left_neighbor_position (tb, 0);
+			    leaf_paste_in_buffer (&bi, n + item_pos - ret_val, l_pos_in_item,
+						  tb->insert_size[0], body, zeros_num);
+
+			    /* previous string prepared space for pasting new entry, following string pastes this entry */
+
+			    /* when we have merge directory item, pos_in_item has been changed too */
+
+			    /* paste new directory entry. 1 is entry number */
+			    leaf_paste_entries (bi.bi_bh, n + item_pos - ret_val, l_pos_in_item, 1,
+						(struct reiserfs_de_head *)body, 
+						body + DEH_SIZE, tb->insert_size[0]
+				);
+			    tb->insert_size[0] = 0;
+			} else {
+			    /* new directory item doesn't fall into L[0] */
+			    /* Shift lnum[0]-1 items in whole. Shift lbytes directory entries from directory item number lnum[0] */
+			    leaf_shift_left (tb, tb->lnum[0], tb->lbytes);
+#if 0/*preserve list*/
+			    preserve_shifted(tb, &(PATH_PLAST_BUFFER (tb->tb_path)), tbF0, S0_b_item_order, tb->L[0]);
+			    tbS0 = PATH_PLAST_BUFFER (tb->tb_path);
+#endif
+			}
+			/* Calculate new position to append in item body */
+			pos_in_item -= tb->lbytes;
+		    }
+		    else {
+			/* regular object */
+
+#ifdef CONFIG_REISERFS_CHECK
+			if ( tb->lbytes  <= 0 )
+			    reiserfs_panic(tb->tb_sb, "PAP-12095: balance_leaf: " 
+					   "there is nothing to shift to L[0]. lbytes=%d",
+					   tb->lbytes);
+			if ( pos_in_item != B_N_PITEM_HEAD(tbS0, item_pos)->ih_item_len )
+			    reiserfs_panic(tb->tb_sb, "PAP-12100: balance_leaf: " 
+					   "incorrect position to paste: item_len=%d, pos_in_item=%d",
+					   B_N_PITEM_HEAD(tbS0,item_pos)->ih_item_len, pos_in_item);
+#endif
+
+			if ( tb->lbytes >= pos_in_item ) {
+			    /* appended item will be in L[0] in whole */
+			    int l_n;
+
+			    /* this bytes number must be appended to the last item of L[h] */
+			    l_n = tb->lbytes - pos_in_item;
+
+			    /* Calculate new insert_size[0] */
+			    tb->insert_size[0] -= l_n;
+
+#ifdef CONFIG_REISERFS_CHECK
+			    if ( tb->insert_size[0] <= 0 )
+				reiserfs_panic(tb->tb_sb, "PAP-12105: balance_leaf: " 
+					       "there is nothing to paste into L[0]. insert_size=%d",
+					       tb->insert_size[0]);
+#endif
+
+			    ret_val =  leaf_shift_left(tb,tb->lnum[0], 
+						       B_N_PITEM_HEAD(tbS0,item_pos)->ih_item_len);
+#if 0/*preserve list*/
+			    preserve_shifted(tb, &(PATH_PLAST_BUFFER (tb->tb_path)), tbF0, S0_b_item_order, tb->L[0]);
+			    tbS0 = PATH_PLAST_BUFFER (tb->tb_path);
+#endif
+			    /* Append to body of item in L[0] */
+			    bi.tb = tb;
+			    bi.bi_bh = tb->L[0];
+			    bi.bi_parent = tb->FL[0];
+			    bi.bi_position = get_left_neighbor_position (tb, 0);
+			    leaf_paste_in_buffer(
+				&bi,n + item_pos - ret_val,
+				B_N_PITEM_HEAD(tb->L[0],n+item_pos-ret_val)->ih_item_len,
+				l_n,body, zeros_num > l_n ? l_n : zeros_num
+				);
+
+#ifdef CONFIG_REISERFS_CHECK
+			    if (l_n && is_indirect_le_ih(B_N_PITEM_HEAD(tb->L[0],
+									n + item_pos - ret_val)))
+				reiserfs_panic(tb->tb_sb, "PAP-12110: balance_leaf: "
+					       "pasting more than 1 unformatted node pointer into indirect item");
+#endif
+
+			    /* 0-th item in S0 can be only of DIRECT type when l_n != 0*/
+			    {
+			      int version;
+
+			      version = le16_to_cpu (B_N_PITEM_HEAD (tbS0, 0)->ih_version);
+			      set_le_key_k_offset (version, B_N_PKEY (tbS0, 0), 
+						   le_key_k_offset (version, B_N_PKEY (tbS0, 0)) + l_n);
+			      set_le_key_k_offset (version, B_N_PDELIM_KEY(tb->CFL[0],tb->lkey[0]),
+						   le_key_k_offset (version, B_N_PDELIM_KEY(tb->CFL[0],tb->lkey[0])) + l_n);
+			    }
+#if 0
+			    set_le_key_k_offset (B_PRIGHT_DELIM_KEY(tb->L[0]), le_key_k_offset (B_PRIGHT_DELIM_KEY(tb->L[0])) + l_n);
+#endif
+			    /*    k_offset (B_N_PKEY (tbS0, 0)) += l_n;
+				  k_offset (B_N_PDELIM_KEY(tb->CFL[0],tb->lkey[0])) += l_n;
+				  k_offset (B_PRIGHT_DELIM_KEY(tb->L[0])) += l_n;*/
+
+#ifdef NO_CONFIG_REISERFS_CHECK /* journal victim */
+			    if (!buffer_dirty (tbS0) || !buffer_dirty (tb->CFL[0]) || !buffer_dirty (tb->L[0]))
+				reiserfs_panic(tb->tb_sb, "PAP-12115: balance_leaf: L, CLF and S must be dirty already");
+#endif
+
+			    /* Calculate new body, position in item and insert_size[0] */
+			    if ( l_n > zeros_num ) {
+				body += (l_n - zeros_num);
+				zeros_num = 0;
+			    }
+			    else
+				zeros_num -= l_n;
+			    pos_in_item = 0;	
+
+#ifdef CONFIG_REISERFS_CHECK	
+			    if (comp_short_le_keys (B_N_PKEY(tbS0,0),
+						    B_N_PKEY(tb->L[0],B_NR_ITEMS(tb->L[0])-1)) ||
+				!op_is_left_mergeable (B_N_PKEY (tbS0, 0), tbS0->b_size) ||
+				!op_is_left_mergeable(B_N_PDELIM_KEY(tb->CFL[0],tb->lkey[0]), tbS0->b_size))
+				reiserfs_panic (tb->tb_sb, "PAP-12120: balance_leaf: "
+						"item must be merge-able with left neighboring item");
+#endif
+
+			}
+			else /* only part of the appended item will be in L[0] */
+			{
+			    /* Calculate position in item for append in S[0] */
+			    pos_in_item -= tb->lbytes;
+
+#ifdef CONFIG_REISERFS_CHECK
+			    if ( pos_in_item <= 0 )
+				reiserfs_panic(tb->tb_sb, "PAP-12125: balance_leaf: "
+					       "no place for paste. pos_in_item=%d", pos_in_item);
+#endif
+
+			    /* Shift lnum[0] - 1 items in whole. Shift lbytes - 1 byte from item number lnum[0] */
+			    leaf_shift_left(tb,tb->lnum[0],tb->lbytes);
+#if 0/*preserve list*/
+			    preserve_shifted(tb, &(PATH_PLAST_BUFFER (tb->tb_path)), tbF0, S0_b_item_order, tb->L[0]);
+			    tbS0 = PATH_PLAST_BUFFER (tb->tb_path);
+#endif
+			}
+		    }
+		}
+		else /* appended item will be in L[0] in whole */
+		{
+		    struct item_head * pasted;
+
+#ifdef REISERFS_FSCK
+		    if ( ! item_pos  && is_left_mergeable (tb->tb_sb, tb->tb_path) == 1 )
+#else
+			if ( ! item_pos  && op_is_left_mergeable (B_N_PKEY (tbS0, 0), tbS0->b_size) )
+#endif
+			{ /* if we paste into first item of S[0] and it is left mergable */
+			    /* then increment pos_in_item by the size of the last item in L[0] */
+			    pasted = B_N_PITEM_HEAD(tb->L[0],n-1);
+			    if ( is_direntry_le_ih (pasted) )
+				pos_in_item += le16_to_cpu (pasted->u.ih_entry_count);
+			    else
+				pos_in_item += le16_to_cpu (pasted->ih_item_len);
+			}
+
+		    /* Shift lnum[0] - 1 items in whole. Shift lbytes - 1 byte from item number lnum[0] */
+		    ret_val = leaf_shift_left(tb,tb->lnum[0],tb->lbytes);
+#if 0/*preserve list*/
+		    preserve_shifted(tb, &(PATH_PLAST_BUFFER (tb->tb_path)), tbF0, S0_b_item_order, tb->L[0]);
+		    tbS0 = PATH_PLAST_BUFFER (tb->tb_path);
+#endif
+		    /* Append to body of item in L[0] */
+		    bi.tb = tb;
+		    bi.bi_bh = tb->L[0];
+		    bi.bi_parent = tb->FL[0];
+		    bi.bi_position = get_left_neighbor_position (tb, 0);
+		    leaf_paste_in_buffer (&bi, n + item_pos - ret_val, pos_in_item, tb->insert_size[0],
+					  body, zeros_num);
+
+		    /* if appended item is directory, paste entry */
+		    pasted = B_N_PITEM_HEAD (tb->L[0], n + item_pos - ret_val);
+		    if (is_direntry_le_ih (pasted))
+			leaf_paste_entries (
+			    bi.bi_bh, n + item_pos - ret_val, pos_in_item, 1, 
+			    (struct reiserfs_de_head *)body, body + DEH_SIZE, tb->insert_size[0]
+			    );
+		    /* if appended item is indirect item, put unformatted node into un list */
+		    if (is_indirect_le_ih (pasted))
+			set_ih_free_space (pasted, ((struct unfm_nodeinfo*)body)->unfm_freespace);
+		    tb->insert_size[0] = 0;
+		    zeros_num = 0;
+		}
+		break;
+	    default:    /* cases d and t */
+		reiserfs_panic (tb->tb_sb, "PAP-12130: balance_leaf: lnum > 0: unexpectable mode: %s(%d)",
+				(flag == M_DELETE) ? "DELETE" : ((flag == M_CUT) ? "CUT" : "UNKNOWN"), flag);
+	    }
+	} else { 
+	    /* new item doesn't fall into L[0] */
+	    leaf_shift_left(tb,tb->lnum[0],tb->lbytes);
+#if 0/*preserve list*/
+	    preserve_shifted(tb, &(PATH_PLAST_BUFFER (tb->tb_path)), tbF0, S0_b_item_order, tb->L[0]);
+	    tbS0 = PATH_PLAST_BUFFER (tb->tb_path);
+#endif
+	}
+    }	/* tb->lnum[0] > 0 */
+
+    /* Calculate new item position */
+    item_pos -= ( tb->lnum[0] - (( tb->lbytes != -1 ) ? 1 : 0));
+
+    if ( tb->rnum[0] > 0 ) {
+	/* shift rnum[0] items from S[0] to the right neighbor R[0] */
+	n = B_NR_ITEMS(tbS0);
+	switch ( flag ) {
+
+	case M_INSERT:   /* insert item */
+	    if ( n - tb->rnum[0] < item_pos )
+	    { /* new item or its part falls to R[0] */
+		if ( item_pos == n - tb->rnum[0] + 1 && tb->rbytes != -1 )
+		{ /* part of new item falls into R[0] */
+		    int old_key_comp, old_len, r_zeros_number;
+		    const char * r_body;
+		    int version;
+		    loff_t offset;
+
+#ifdef CONFIG_REISERFS_CHECK
+		    if ( !is_direct_le_ih (ih) )
+			reiserfs_panic(tb->tb_sb, "PAP-12135: balance_leaf: "
+				       "only direct item can be split. (%h)", ih);
+#endif
+
+		    leaf_shift_right(tb,tb->rnum[0]-1,-1);
+#if 0/*preserve list*/
+		    if (tb->rnum[0]>1) {
+			preserve_shifted(tb, &(PATH_PLAST_BUFFER (tb->tb_path)), tbF0, S0_b_item_order, tb->R[0]);
+			tbS0 = PATH_PLAST_BUFFER (tb->tb_path);
+		    }
+#endif
+
+		    version = le16_to_cpu (ih->ih_version);
+		    /* Remember key component and item length */
+		    old_key_comp = le_key_k_offset (version, &(ih->ih_key));
+		    old_len = le16_to_cpu (ih->ih_item_len);
+
+		    /* Calculate key component and item length to insert into R[0] */
+		    offset = le_key_k_offset (version, &(ih->ih_key)) + (old_len - tb->rbytes);
+		    set_le_key_k_offset (version, &(ih->ih_key), offset);
+		    ih->ih_item_len = cpu_to_le16 (tb->rbytes);
+		    /* Insert part of the item into R[0] */
+		    bi.tb = tb;
+		    bi.bi_bh = tb->R[0];
+		    bi.bi_parent = tb->FR[0];
+		    bi.bi_position = get_right_neighbor_position (tb, 0);
+		    if ( offset - old_key_comp > zeros_num ) {
+			r_zeros_number = 0;
+			r_body = body + offset - old_key_comp - zeros_num;
+		    }
+		    else {
+			r_body = body;
+			r_zeros_number = zeros_num - (offset - old_key_comp);
+			zeros_num -= r_zeros_number;
+		    }
+
+		    leaf_insert_into_buf (&bi, 0, ih, r_body, r_zeros_number);
+
+		    /* Replace right delimiting key by first key in R[0] */
+		    replace_key(tb, tb->CFR[0],tb->rkey[0],tb->R[0],0);
+
+		    /* Calculate key component and item length to insert into S[0] */
+		    set_le_key_k_offset (version, &(ih->ih_key), old_key_comp);
+		    ih->ih_item_len = cpu_to_le16 (old_len - tb->rbytes);
+
+		    tb->insert_size[0] -= tb->rbytes;
+
+		}
+		else /* whole new item falls into R[0] */
+		{					  
+		    /* Shift rnum[0]-1 items to R[0] */
+		    ret_val = leaf_shift_right(tb,tb->rnum[0]-1,tb->rbytes);
+#if 0/*preserve list*/
+		    if (tb->rnum[0]>1) {
+			preserve_shifted(tb, &(PATH_PLAST_BUFFER (tb->tb_path)), tbF0, S0_b_item_order, tb->R[0]);
+			tbS0 = PATH_PLAST_BUFFER (tb->tb_path);
+		    }
+#endif
+		    /* Insert new item into R[0] */
+		    bi.tb = tb;
+		    bi.bi_bh = tb->R[0];
+		    bi.bi_parent = tb->FR[0];
+		    bi.bi_position = get_right_neighbor_position (tb, 0);
+		    leaf_insert_into_buf (&bi, item_pos - n + tb->rnum[0] - 1, ih, body, zeros_num);
+#if 0/*preserve list*/
+		    if (tb->preserve_mode == PRESERVE_INDIRECT_TO_DIRECT){
+			mark_suspected_recipient (tb->tb_sb, bi.bi_bh);
+		    }
+#endif
+
+		    /* If we insert new item in the begin of R[0] change the right delimiting key */
+		    if ( item_pos - n + tb->rnum[0] - 1 == 0 ) {
+			replace_key(tb, tb->CFR[0],tb->rkey[0],tb->R[0],0);
+
+#if 0
+			/* update right delimiting key */
+			copy_key(B_PRIGHT_DELIM_KEY(tbS0), &(ih->ih_key));
+			reiserfs_mark_buffer_dirty (tbS0, 0);
+#endif
+		    }
+		    zeros_num = tb->insert_size[0] = 0;
+		}
+	    }
+	    else /* new item or part of it doesn't fall into R[0] */
+	    {
+		leaf_shift_right(tb,tb->rnum[0],tb->rbytes);
+#if 0/*preserve list*/
+		preserve_shifted(tb, &(PATH_PLAST_BUFFER (tb->tb_path)), tbF0, S0_b_item_order, tb->R[0]);
+		tbS0 = PATH_PLAST_BUFFER (tb->tb_path);
+#endif
+	    }
+	    break;
+
+	case M_PASTE:   /* append item */
+
+	    if ( n - tb->rnum[0] <= item_pos )  /* pasted item or part of it falls to R[0] */
+	    {
+		if ( item_pos == n - tb->rnum[0] && tb->rbytes != -1 )
+		{ /* we must shift the part of the appended item */
+		    if ( is_direntry_le_ih (B_N_PITEM_HEAD(tbS0, item_pos)))
+		    { /* we append to directory item */
+			int entry_count;
+
+#ifdef CONFIG_REISERFS_CHECK
+			if ( zeros_num )
+			    reiserfs_panic(tb->tb_sb, "PAP-12145: balance_leaf: illegal parametr in case of a directory");
+#endif
+
+			entry_count = I_ENTRY_COUNT(B_N_PITEM_HEAD(tbS0, item_pos));
+			if ( entry_count - tb->rbytes < pos_in_item )
+			    /* new directory entry falls into R[0] */
+			{
+			    int paste_entry_position;
+
+#ifdef CONFIG_REISERFS_CHECK
+			    if ( tb->rbytes - 1 >= entry_count || ! tb->insert_size[0] )
+				reiserfs_panic(tb->tb_sb, "PAP-12150: balance_leaf: "
+					       "no enough of entries to shift to R[0]: rbytes=%d, entry_count=%d",
+					       tb->rbytes, entry_count);
+#endif
+
+			    /* Shift rnum[0]-1 items in whole. Shift rbytes-1 directory entries from directory item number rnum[0] */
+			    leaf_shift_right(tb,tb->rnum[0],tb->rbytes - 1);
+#if 0/*preserve list*/
+			    /* if we are shifting more than just the new entry */
+			    if (tb->rbytes > 1 || tb->rnum[0] > 1) {
+				preserve_shifted(tb, &(PATH_PLAST_BUFFER (tb->tb_path)), tbF0, S0_b_item_order, tb->R[0]);
+				tbS0 = PATH_PLAST_BUFFER (tb->tb_path);
+			    }
+#endif
+			    /* Paste given directory entry to directory item */
+			    paste_entry_position = pos_in_item - entry_count + tb->rbytes - 1;
+			    bi.tb = tb;
+			    bi.bi_bh = tb->R[0];
+			    bi.bi_parent = tb->FR[0];
+			    bi.bi_position = get_right_neighbor_position (tb, 0);
+			    leaf_paste_in_buffer (&bi, 0, paste_entry_position,
+						  tb->insert_size[0],body,zeros_num);
+			    /* paste entry */
+			    leaf_paste_entries (
+				bi.bi_bh, 0, paste_entry_position, 1, (struct reiserfs_de_head *)body, 
+				body + DEH_SIZE, tb->insert_size[0]
+				);								
+						
+			    if ( paste_entry_position == 0 ) {
+				/* change delimiting keys */
+				replace_key(tb, tb->CFR[0],tb->rkey[0],tb->R[0],0);
+#if 0
+				copy_key(B_PRIGHT_DELIM_KEY(tbS0), B_N_PKEY(tb->R[0], 0));
+				reiserfs_mark_buffer_dirty (tbS0, 0);
+#endif
+			    }
+
+			    tb->insert_size[0] = 0;
+			    pos_in_item++;
+			}
+			else /* new directory entry doesn't fall into R[0] */
+			{
+			    leaf_shift_right(tb,tb->rnum[0],tb->rbytes);
+#if 0/*preserve list*/
+			    preserve_shifted(tb, &(PATH_PLAST_BUFFER (tb->tb_path)), tbF0, S0_b_item_order, tb->R[0]);
+			    tbS0 = PATH_PLAST_BUFFER (tb->tb_path);
+#endif
+			}
+		    }
+		    else /* regular object */
+		    {
+			int n_shift, n_rem, r_zeros_number;
+			const char * r_body;
+
+			/* Calculate number of bytes which must be shifted from appended item */
+			if ( (n_shift = tb->rbytes - tb->insert_size[0]) < 0 )
+			    n_shift = 0;
+
+#ifdef CONFIG_REISERFS_CHECK
+			if (pos_in_item != B_N_PITEM_HEAD (tbS0, item_pos)->ih_item_len)
+			    reiserfs_panic(tb->tb_sb,"PAP-12155: balance_leaf: invalid position to paste. ih_item_len=%d, pos_in_item=%d",
+					   pos_in_item, B_N_PITEM_HEAD(tbS0,item_pos)->ih_item_len);
+#endif
+
+			leaf_shift_right(tb,tb->rnum[0],n_shift);
+#if 0/*preserve list*/
+			/* if we are shifting an old part from the appended item or more than the appended item is going into R */
+			if (n_shift || tb->rnum[0] > 1) {
+			    preserve_shifted(tb, &(PATH_PLAST_BUFFER (tb->tb_path)), tbF0, S0_b_item_order, tb->R[0]);
+			    tbS0 = PATH_PLAST_BUFFER (tb->tb_path);
+			}
+#endif
+			/* Calculate number of bytes which must remain in body after appending to R[0] */
+			if ( (n_rem = tb->insert_size[0] - tb->rbytes) < 0 )
+			    n_rem = 0;
+			
+			{
+			  int version;
+			  
+			  version = ih_version (B_N_PITEM_HEAD (tb->R[0],0));
+			  set_le_key_k_offset (version, B_N_PKEY(tb->R[0],0), 
+					       le_key_k_offset (version, B_N_PKEY(tb->R[0],0)) + n_rem);
+			  set_le_key_k_offset (version, B_N_PDELIM_KEY(tb->CFR[0],tb->rkey[0]), 
+					       le_key_k_offset (version, B_N_PDELIM_KEY(tb->CFR[0],tb->rkey[0])) + n_rem);
+			}
+/*		  k_offset (B_N_PKEY(tb->R[0],0)) += n_rem;
+		  k_offset (B_N_PDELIM_KEY(tb->CFR[0],tb->rkey[0])) += n_rem;*/
+			do_balance_mark_internal_dirty (tb, tb->CFR[0], 0);
+
+#if 0
+			set_le_key_k_offset (B_PRIGHT_DELIM_KEY(tbS0), le_key_k_offset (B_PRIGHT_DELIM_KEY(tbS0)) + n_rem);
+/*		  k_offset (B_PRIGHT_DELIM_KEY(tbS0)) += n_rem;*/
+			reiserfs_mark_buffer_dirty (tbS0, 0);
+#endif
+			/* Append part of body into R[0] */
+			bi.tb = tb;
+			bi.bi_bh = tb->R[0];
+			bi.bi_parent = tb->FR[0];
+			bi.bi_position = get_right_neighbor_position (tb, 0);
+			if ( n_rem > zeros_num ) {
+			    r_zeros_number = 0;
+			    r_body = body + n_rem - zeros_num;
+			}
+			else {
+			    r_body = body;
+			    r_zeros_number = zeros_num - n_rem;
+			    zeros_num -= r_zeros_number;
+			}
+
+			leaf_paste_in_buffer(&bi, 0, n_shift, tb->insert_size[0] - n_rem, r_body, r_zeros_number);
+
+			if (is_indirect_le_ih (B_N_PITEM_HEAD(tb->R[0],0))) {
+
+#ifdef CONFIG_REISERFS_CHECK
+			    if (n_rem)
+				reiserfs_panic(tb->tb_sb, "PAP-12160: balance_leaf: paste more than one unformatted node pointer");
+#endif
+
+			    set_ih_free_space (B_N_PITEM_HEAD(tb->R[0],0), ((struct unfm_nodeinfo*)body)->unfm_freespace);
+			}
+
+			tb->insert_size[0] = n_rem;
+			if ( ! n_rem )
+			    pos_in_item ++;
+		    }
+		}
+		else /* pasted item in whole falls into R[0] */
+		{
+		    struct item_head * pasted;
+
+		    ret_val = leaf_shift_right(tb,tb->rnum[0],tb->rbytes);
+#if 0/*preserve list*/
+		    preserve_shifted(tb, &(PATH_PLAST_BUFFER (tb->tb_path)), tbF0, S0_b_item_order, tb->R[0]);
+		    tbS0 = PATH_PLAST_BUFFER (tb->tb_path);
+#endif
+		    /* append item in R[0] */
+		    if ( pos_in_item >= 0 ) {
+			bi.tb = tb;
+			bi.bi_bh = tb->R[0];
+			bi.bi_parent = tb->FR[0];
+			bi.bi_position = get_right_neighbor_position (tb, 0);
+			leaf_paste_in_buffer(&bi,item_pos - n + tb->rnum[0], pos_in_item,
+					     tb->insert_size[0],body, zeros_num);
+		    }
+
+		    /* paste new entry, if item is directory item */
+		    pasted = B_N_PITEM_HEAD(tb->R[0], item_pos - n + tb->rnum[0]);
+		    if (is_direntry_le_ih (pasted) && pos_in_item >= 0 ) {
+			leaf_paste_entries (
+			    bi.bi_bh, item_pos - n + tb->rnum[0], pos_in_item, 1, 
+			    (struct reiserfs_de_head *)body, body + DEH_SIZE, tb->insert_size[0]
+			    );
+			if ( ! pos_in_item ) {
+
+#ifdef CONFIG_REISERFS_CHECK
+			    if ( item_pos - n + tb->rnum[0] )
+				reiserfs_panic (tb->tb_sb, "PAP-12165: balance_leaf: " 
+						"directory item must be first item of node when pasting is in 0th position");
+#endif
+
+			    /* update delimiting keys */
+			    replace_key(tb, tb->CFR[0],tb->rkey[0],tb->R[0],0);
+#if 0
+			    copy_key(B_PRIGHT_DELIM_KEY(tbS0),B_N_PKEY(tb->R[0], 0));
+			    reiserfs_mark_buffer_dirty (tbS0, 0);
+#endif
+			}
+		    }
+
+		    if (is_indirect_le_ih (pasted))
+			set_ih_free_space (pasted, ((struct unfm_nodeinfo*)body)->unfm_freespace);
+		    zeros_num = tb->insert_size[0] = 0;
+		}
+	    }
+	    else /* new item doesn't fall into R[0] */
+	    {
+		leaf_shift_right(tb,tb->rnum[0],tb->rbytes);
+#if 0/*preserve list*/
+		preserve_shifted(tb, &(PATH_PLAST_BUFFER (tb->tb_path)), tbF0, S0_b_item_order, tb->R[0]);
+		tbS0 = PATH_PLAST_BUFFER (tb->tb_path);
+#endif
+	    }
+	    break;
+	default:    /* cases d and t */
+	    reiserfs_panic (tb->tb_sb, "PAP-12175: balance_leaf: rnum > 0: unexpectable mode: %s(%d)",
+			    (flag == M_DELETE) ? "DELETE" : ((flag == M_CUT) ? "CUT" : "UNKNOWN"), flag);
+	}
+    
+    }	/* tb->rnum[0] > 0 */
+
+
+#ifdef CONFIG_REISERFS_CHECK
+    if ( tb->blknum[0] > 3 )  
+	reiserfs_panic (tb->tb_sb, "PAP-12180: balance_leaf: blknum can not be %d. It must be <= 3",  tb->blknum[0]);
+
+    if ( tb->blknum[0] < 0 )  
+	reiserfs_panic (tb->tb_sb, "PAP-12185: balance_leaf: blknum can not be %d. It must be >= 0",  tb->blknum[0]);
+#endif
+
+    /* if while adding to a node we discover that it is possible to split
+       it in two, and merge the left part into the left neighbor and the
+       right part into the right neighbor, eliminating the node */
+    if ( tb->blknum[0] == 0 ) { /* node S[0] is empty now */
+
+#ifdef CONFIG_REISERFS_CHECK
+	if ( ! tb->lnum[0] || ! tb->rnum[0] )
+	    reiserfs_panic(tb->tb_sb, "PAP-12190: balance_leaf: lnum and rnum must not be zero");
+#if 0
+	if (COMP_KEYS (B_N_PKEY(tb->R[0], 0), B_PRIGHT_DELIM_KEY(tbS0)))
+	    reiserfs_panic (tb->tb_sb, "vs-12192: balance_leaf: S[0] is being removed from the tree, it has incorrect right delimiting key");
+#endif
+#endif
+
+#if 0
+	/* if insertion was done before 0-th position in R[0], right
+	   delimiting key of the tb->L[0]'s and left delimiting key are
+	   not set correctly */
+	if (tb->L[0]) {
+	    copy_key(B_PRIGHT_DELIM_KEY(tb->L[0]), B_PRIGHT_DELIM_KEY(tbS0));
+	    reiserfs_mark_buffer_dirty (tb->L[0], 0);
+	}
+
+	if (tb->CFL[0]) {
+	    copy_key (B_N_PDELIM_KEY (tb->CFL[0], tb->lkey[0]), B_PRIGHT_DELIM_KEY(tbS0));
+	    reiserfs_mark_buffer_dirty (tb->CFL[0], 0);
+	}
+#endif
+    
+	/* if insertion was done before 0-th position in R[0], right
+	   delimiting key of the tb->L[0]'s and left delimiting key are
+	   not set correctly */
+	if (tb->CFL[0]) {
+	    if (!tb->CFR[0])
+		reiserfs_panic (tb->tb_sb, "vs-12195: balance_leaf: CFR not initialized");
+	    copy_key (B_N_PDELIM_KEY (tb->CFL[0], tb->lkey[0]), B_N_PDELIM_KEY (tb->CFR[0], tb->rkey[0]));
+	    do_balance_mark_internal_dirty (tb, tb->CFL[0], 0);
+	}
+
+	reiserfs_invalidate_buffer(tb,tbS0);									
+	return 0;
+    }
+
+
+    /* Fill new nodes that appear in place of S[0] */
+
+    /* I am told that this copying is because we need an array to enable
+       the looping code. -Hans */
+    snum[0] = tb->s1num,
+	snum[1] = tb->s2num;
+    sbytes[0] = tb->s1bytes;
+    sbytes[1] = tb->s2bytes;
+    for( i = tb->blknum[0] - 2; i >= 0; i-- ) {
+
+#ifdef CONFIG_REISERFS_CHECK
+	if (!snum[i])
+	    reiserfs_panic(tb->tb_sb,"PAP-12200: balance_leaf: snum[%d] == %d. Must be > 0", i, snum[i]);
+#endif /* CONFIG_REISERFS_CHECK */
+
+	/* here we shift from S to S_new nodes */
+
+	S_new[i] = get_FEB(tb);
+
+	/* initialized block type and tree level */
+	B_BLK_HEAD(S_new[i])->blk_level = cpu_to_le16 (DISK_LEAF_NODE_LEVEL);
+
+
+	n = B_NR_ITEMS(tbS0);
+	
+	switch (flag) {
+	case M_INSERT:   /* insert item */
+
+	    if ( n - snum[i] < item_pos )
+	    { /* new item or it's part falls to first new node S_new[i]*/
+		if ( item_pos == n - snum[i] + 1 && sbytes[i] != -1 )
+		{ /* part of new item falls into S_new[i] */
+		    int old_key_comp, old_len, r_zeros_number;
+		    const char * r_body;
+		    int version;
+
+#ifdef CONFIG_REISERFS_CHECK
+		    if ( !is_direct_le_ih(ih) )
+			/* The items which can be inserted are:
+			   Stat_data item, direct item, indirect item and directory item which consist of only two entries "." and "..".
+			   These items must not be broken except for a direct one. */
+			reiserfs_panic(tb->tb_sb, "PAP-12205: balance_leaf: "
+				       "non-direct item can not be broken when inserting");
+#endif
+
+		    /* Move snum[i]-1 items from S[0] to S_new[i] */
+		    leaf_move_items (LEAF_FROM_S_TO_SNEW, tb, snum[i] - 1, -1, S_new[i]);
+#if 0/*preserve list*/
+		    if (snum[i] > 1 ) {
+			preserve_shifted(tb, &(PATH_PLAST_BUFFER (tb->tb_path)), tbF0, S0_b_item_order, S_new[i]);
+			tbS0 = PATH_PLAST_BUFFER (tb->tb_path);
+		    }
+#endif
+		    /* Remember key component and item length */
+		    version = ih_version (ih);
+		    old_key_comp = le_key_k_offset (version, &(ih->ih_key));
+		    old_len = le16_to_cpu (ih->ih_item_len);
+
+		    /* Calculate key component and item length to insert into S_new[i] */
+		    set_le_key_k_offset (version, &(ih->ih_key), 
+					 le_key_k_offset (version, &(ih->ih_key)) + (old_len - sbytes[i]));
+
+		    ih->ih_item_len = cpu_to_le16 (sbytes[i]);
+
+		    /* Insert part of the item into S_new[i] before 0-th item */
+		    bi.tb = tb;
+		    bi.bi_bh = S_new[i];
+		    bi.bi_parent = 0;
+		    bi.bi_position = 0;
+
+		    if ( le_key_k_offset (version, &(ih->ih_key)) - old_key_comp > zeros_num ) {
+			r_zeros_number = 0;
+			r_body = body + (le_key_k_offset (version, &(ih->ih_key)) - old_key_comp) - zeros_num;
+		    }
+		    else {
+			r_body = body;
+			r_zeros_number = zeros_num - (le_key_k_offset (version, &(ih->ih_key)) - old_key_comp);
+			zeros_num -= r_zeros_number;
+		    }
+
+		    leaf_insert_into_buf (&bi, 0, ih, r_body, r_zeros_number);
+
+		    /* Calculate key component and item length to insert into S[i] */
+		    set_le_key_k_offset (version, &(ih->ih_key), old_key_comp);
+		    ih->ih_item_len = cpu_to_le16 (old_len - sbytes[i]);
+		    tb->insert_size[0] -= sbytes[i];
+		}
+		else /* whole new item falls into S_new[i] */
+		{
+		    /* Shift snum[0] - 1 items to S_new[i] (sbytes[i] of split item) */
+		    leaf_move_items (LEAF_FROM_S_TO_SNEW, tb, snum[i] - 1, sbytes[i], S_new[i]);
+
+		    /* Insert new item into S_new[i] */
+		    bi.tb = tb;
+		    bi.bi_bh = S_new[i];
+		    bi.bi_parent = 0;
+		    bi.bi_position = 0;
+		    leaf_insert_into_buf (&bi, item_pos - n + snum[i] - 1, ih, body, zeros_num);
+#if 0/*preserve list*/
+		    if (tb->preserve_mode == PRESERVE_INDIRECT_TO_DIRECT){
+			mark_suspected_recipient (tb->tb_sb, bi.bi_bh);
+		    }
+#endif
+
+		    zeros_num = tb->insert_size[0] = 0;
+		}
+	    }
+
+	    else /* new item or it part don't falls into S_new[i] */
+	    {
+		leaf_move_items (LEAF_FROM_S_TO_SNEW, tb, snum[i], sbytes[i], S_new[i]);
+#if 0/*preserve list*/
+		preserve_shifted(tb, &(PATH_PLAST_BUFFER (tb->tb_path)), tbF0, S0_b_item_order, S_new[i]);
+		tbS0 = PATH_PLAST_BUFFER (tb->tb_path);
+#endif
+	    }
+	    break;
+
+	case M_PASTE:   /* append item */
+
+	    if ( n - snum[i] <= item_pos )  /* pasted item or part if it falls to S_new[i] */
+	    {
+		if ( item_pos == n - snum[i] && sbytes[i] != -1 )
+		{ /* we must shift part of the appended item */
+		    struct item_head * aux_ih;
+
+#ifdef CONFIG_REISERFS_CHECK
+		    if ( ih )
+			reiserfs_panic (tb->tb_sb, "PAP-12210: balance_leaf: ih must be 0");
+#endif /* CONFIG_REISERFS_CHECK */
+
+		    if ( is_direntry_le_ih (aux_ih = B_N_PITEM_HEAD(tbS0,item_pos))) {
+			/* we append to directory item */
+
+			int entry_count;
+		
+			entry_count = le16_to_cpu (aux_ih->u.ih_entry_count);
+
+			if ( entry_count - sbytes[i] < pos_in_item  && pos_in_item <= entry_count ) {
+			    /* new directory entry falls into S_new[i] */
+		  
+#ifdef CONFIG_REISERFS_CHECK
+			    if ( ! tb->insert_size[0] )
+				reiserfs_panic (tb->tb_sb, "PAP-12215: balance_leaif: insert_size is already 0");
+			    if ( sbytes[i] - 1 >= entry_count )
+				reiserfs_panic (tb->tb_sb, "PAP-12220: balance_leaf: "
+						"there are no so much entries (%d), only %d",
+						sbytes[i] - 1, entry_count);
+#endif
+
+			    /* Shift snum[i]-1 items in whole. Shift sbytes[i] directory entries from directory item number snum[i] */
+			    leaf_move_items (LEAF_FROM_S_TO_SNEW, tb, snum[i], sbytes[i]-1, S_new[i]);
+#if 0/*preserve list*/
+			    /* if more than the affected item is shifted, or if more than
+			       one entry (from the affected item) is shifted */
+			    if (snum[i] > 1 || sbytes[i] > 1) {
+				preserve_shifted(tb, &(PATH_PLAST_BUFFER (tb->tb_path)), tbF0, S0_b_item_order, S_new[i]);
+				tbS0 = PATH_PLAST_BUFFER (tb->tb_path);
+			    }
+#endif
+			    /* Paste given directory entry to directory item */
+			    bi.tb = tb;
+			    bi.bi_bh = S_new[i];
+			    bi.bi_parent = 0;
+			    bi.bi_position = 0;
+			    leaf_paste_in_buffer (&bi, 0, pos_in_item - entry_count + sbytes[i] - 1,
+						  tb->insert_size[0], body,zeros_num);
+			    /* paste new directory entry */
+			    leaf_paste_entries (
+				bi.bi_bh, 0, pos_in_item - entry_count + sbytes[i] - 1,
+				1, (struct reiserfs_de_head *)body, body + DEH_SIZE,
+				tb->insert_size[0]
+				);
+			    tb->insert_size[0] = 0;
+			    pos_in_item++;
+			} else { /* new directory entry doesn't fall into S_new[i] */
+			    leaf_move_items (LEAF_FROM_S_TO_SNEW, tb, snum[i], sbytes[i], S_new[i]);
+			}
+		    }
+		    else /* regular object */
+		    {
+			int n_shift, n_rem, r_zeros_number;
+			const char * r_body;
+
+#ifdef CONFIG_REISERFS_CHECK
+			if ( pos_in_item != B_N_PITEM_HEAD(tbS0,item_pos)->ih_item_len ||
+			     tb->insert_size[0] <= 0 )
+			    reiserfs_panic (tb->tb_sb, "PAP-12225: balance_leaf: item too short or insert_size <= 0");
+#endif
+
+			/* Calculate number of bytes which must be shifted from appended item */
+			n_shift = sbytes[i] - tb->insert_size[0];
+			if ( n_shift < 0 )
+			    n_shift = 0;
+			leaf_move_items (LEAF_FROM_S_TO_SNEW, tb, snum[i], n_shift, S_new[i]);
+
+			/* Calculate number of bytes which must remain in body after append to S_new[i] */
+			n_rem = tb->insert_size[0] - sbytes[i];
+			if ( n_rem < 0 )
+			    n_rem = 0;
+			/* Append part of body into S_new[0] */
+			bi.tb = tb;
+			bi.bi_bh = S_new[i];
+			bi.bi_parent = 0;
+			bi.bi_position = 0;
+
+			if ( n_rem > zeros_num ) {
+			    r_zeros_number = 0;
+			    r_body = body + n_rem - zeros_num;
+			}
+			else {
+			    r_body = body;
+			    r_zeros_number = zeros_num - n_rem;
+			    zeros_num -= r_zeros_number;
+			}
+
+			leaf_paste_in_buffer(&bi, 0, n_shift, tb->insert_size[0]-n_rem, r_body,r_zeros_number);
+			{
+			    struct item_head * tmp;
+
+			    tmp = B_N_PITEM_HEAD(S_new[i],0);
+			    if (is_indirect_le_ih (tmp)) {
+				if (n_rem)
+				    reiserfs_panic (tb->tb_sb, "PAP-12230: balance_leaf: invalid action with indirect item");
+				set_ih_free_space (tmp, ((struct unfm_nodeinfo*)body)->unfm_freespace);
+			    }
+			    set_le_key_k_offset (ih_version (tmp), &tmp->ih_key, 
+						 le_key_k_offset (ih_version (tmp), &tmp->ih_key) + n_rem);
+			}
+
+			tb->insert_size[0] = n_rem;
+			if ( ! n_rem )
+			    pos_in_item++;
+		    }
+		}
+		else
+		    /* item falls wholly into S_new[i] */
+		{
+		    int ret_val;
+		    struct item_head * pasted;
+
+#ifdef CONFIG_REISERFS_CHECK
+		    struct item_head * ih = B_N_PITEM_HEAD(tbS0,item_pos);
+
+		    if ( ! is_direntry_le_ih(ih) && (pos_in_item != ih->ih_item_len ||
+						     tb->insert_size[0] <= 0) )
+			reiserfs_panic (tb->tb_sb, "PAP-12235: balance_leaf: pos_in_item must be equal to ih_item_len");
+#endif /* CONFIG_REISERFS_CHECK */
+
+		    ret_val = leaf_move_items (LEAF_FROM_S_TO_SNEW, tb, snum[i], sbytes[i], S_new[i]);
+#if 0/*preserve list*/
+		    /* we must preserve that which we are pasting onto the end of and shifting */
+		    preserve_shifted(tb, &(PATH_PLAST_BUFFER (tb->tb_path)), tbF0, S0_b_item_order, S_new[i]);
+		    tbS0 = PATH_PLAST_BUFFER (tb->tb_path);
+#endif
+
+#ifdef CONFIG_REISERFS_CHECK
+		    if ( ret_val )
+			reiserfs_panic (tb->tb_sb, "PAP-12240: balance_leaf: "
+					"unexpected value returned by leaf_move_items (%d)",
+					ret_val);
+#endif /* CONFIG_REISERFS_CHECK */
+
+		    /* paste into item */
+		    bi.tb = tb;
+		    bi.bi_bh = S_new[i];
+		    bi.bi_parent = 0;
+		    bi.bi_position = 0;
+		    leaf_paste_in_buffer(&bi, item_pos - n + snum[i], pos_in_item, tb->insert_size[0], body, zeros_num);
+
+		    pasted = B_N_PITEM_HEAD(S_new[i], item_pos - n + snum[i]);
+		    if (is_direntry_le_ih (pasted))
+		    {
+			leaf_paste_entries (
+			    bi.bi_bh, item_pos - n + snum[i], pos_in_item, 1, 
+			    (struct reiserfs_de_head *)body, body + DEH_SIZE, tb->insert_size[0]
+			    );
+		    }
+
+		    /* if we paste to indirect item update ih_free_space */
+		    if (is_indirect_le_ih (pasted))
+			set_ih_free_space (pasted, ((struct unfm_nodeinfo*)body)->unfm_freespace);
+		    zeros_num = tb->insert_size[0] = 0;
+		}
+	    }
+
+	    else /* pasted item doesn't fall into S_new[i] */
+	    {
+		leaf_move_items (LEAF_FROM_S_TO_SNEW, tb, snum[i], sbytes[i], S_new[i]);
+#if 0/*preserve list*/
+		preserve_shifted(tb, &(PATH_PLAST_BUFFER (tb->tb_path)), tbF0, S0_b_item_order, S_new[i]);
+		tbS0 = PATH_PLAST_BUFFER (tb->tb_path);
+#endif
+	    }
+	    break;
+	default:    /* cases d and t */
+	    reiserfs_panic (tb->tb_sb, "PAP-12245: balance_leaf: blknum > 2: unexpectable mode: %s(%d)",
+			    (flag == M_DELETE) ? "DELETE" : ((flag == M_CUT) ? "CUT" : "UNKNOWN"), flag);
+	}
+
+	memcpy (insert_key + i,B_N_PKEY(S_new[i],0),KEY_SIZE);
+	insert_ptr[i] = S_new[i];
+
+#ifdef CONFIG_REISERFS_CHECK
+	if (atomic_read (&(S_new[i]->b_count)) != 1) {
+	    if (atomic_read(&(S_new[i]->b_count)) != 2 ||
+	      !(buffer_journaled(S_new[i]) || buffer_journal_dirty(S_new[i]))) {
+	      reiserfs_panic (tb->tb_sb, "PAP-12247: balance_leaf: S_new[%d] : (%b)\n", i, S_new[i]);
+	    }
+	}
+#endif
+
+#if 0
+	/* update right_delimiting_key fields */
+	copy_key (B_PRIGHT_DELIM_KEY (S_new[i]), B_PRIGHT_DELIM_KEY (tbS0));
+	copy_key (B_PRIGHT_DELIM_KEY (tbS0), B_N_PKEY (S_new[i], 0));
+	reiserfs_mark_buffer_dirty (tbS0, 0);
+#endif
+
+    }
+
+    /* if the affected item was not wholly shifted then we perform all necessary operations on that part or whole of the
+       affected item which remains in S */
+    if ( 0 <= item_pos && item_pos < tb->s0num )
+    { /* if we must insert or append into buffer S[0] */
+
+	switch (flag)
+	{
+	case M_INSERT:   /* insert item into S[0] */
+	    bi.tb = tb;
+	    bi.bi_bh = tbS0;
+	    bi.bi_parent = PATH_H_PPARENT (tb->tb_path, 0);
+	    bi.bi_position = PATH_H_POSITION (tb->tb_path, 1);
+	    leaf_insert_into_buf (&bi, item_pos, ih, body, zeros_num);
+#if 0/*preserve list*/
+	    if (tb->preserve_mode == PRESERVE_INDIRECT_TO_DIRECT){
+		mark_suspected_recipient (tb->tb_sb, bi.bi_bh);
+	    }
+#endif
+
+	    /* If we insert the first key change the delimiting key */
+	    if( item_pos == 0 ) {
+		if (tb->CFL[0]) /* can be 0 in reiserfsck */
+		    replace_key(tb, tb->CFL[0], tb->lkey[0],tbS0,0);
+
+#if 0 /* right delim key support */
+#ifdef CONFIG_REISERFS_CHECK
+		if ( ! tb->CFL[0] || ! tb->L[0] || (B_NR_ITEMS (tbS0) > 1 && 
+						    COMP_KEYS(B_PRIGHT_DELIM_KEY(tb->L[0]), B_N_PKEY(tbS0, 1))) )
+		    reiserfs_panic(tb->tb_sb, "PAP-12250: balance_leaf: invalid right delimiting key");
+		if (!buffer_dirty (tb->L[0]) && !(buffer_journaled(tb->L[0]) ||
+		     buffer_journal_dirty(tb->L[0])))
+		    reiserfs_panic (tb->tb_sb, "PAP-12255: balance_leaf: tb->L[0] must be dirty");
+#endif
+		if (tb->L[0]) /* can be 0 in reiserfsck */
+		    copy_key (B_PRIGHT_DELIM_KEY (tb->L[0]), &(ih->ih_key));   
+#endif /* right delim key support */
+	    }
+	    break;
+
+	case M_PASTE: {  /* append item in S[0] */
+	    struct item_head * pasted;
+
+	    pasted = B_N_PITEM_HEAD (tbS0, item_pos);
+	    /* when directory, may be new entry already pasted */
+	    if (is_direntry_le_ih (pasted)) {
+		if ( pos_in_item >= 0 && pos_in_item <= le16_to_cpu (pasted->u.ih_entry_count) ) {
+
+#ifdef CONFIG_REISERFS_CHECK
+		    if ( ! tb->insert_size[0] )
+			reiserfs_panic (tb->tb_sb, "PAP-12260: balance_leaf: insert_size is 0 already");
+#endif /* CONFIG_REISERFS_CHECK */
+
+		    /* prepare space */
+		    bi.tb = tb;
+		    bi.bi_bh = tbS0;
+		    bi.bi_parent = PATH_H_PPARENT (tb->tb_path, 0);
+		    bi.bi_position = PATH_H_POSITION (tb->tb_path, 1);
+		    leaf_paste_in_buffer(&bi, item_pos, pos_in_item, tb->insert_size[0], body, zeros_num);
+
+
+#ifdef CONFIG_REISERFS_CHECK
+#if 0
+		    if ( ! item_pos && ! pos_in_item  && (! tb->L[0] || COMP_KEYS(B_PRIGHT_DELIM_KEY(tb->L[0]), 
+										  B_N_PKEY(tbS0, 0))) )
+			reiserfs_panic(tb->tb_sb, "PAP-12265: balance_leaf: invalid right delimiting key");
+#endif
+#endif
+
+		    /* paste entry */
+		    leaf_paste_entries (
+			bi.bi_bh, item_pos, pos_in_item, 1, (struct reiserfs_de_head *)body,
+			body + DEH_SIZE, tb->insert_size[0]
+			);
+		    if ( ! item_pos && ! pos_in_item ) {
+
+#ifdef CONFIG_REISERFS_CHECK
+			if (!tb->CFL[0] || !tb->L[0])
+			    reiserfs_panic (tb->tb_sb, "PAP-12270: balance_leaf: CFL[0]/L[0] must be specified");
+#endif /* CONFIG_REISERFS_CHECK */
+
+			if (tb->CFL[0]) {
+			    replace_key(tb, tb->CFL[0], tb->lkey[0],tbS0,0);
+
+#if 0
+			    /* update right delimiting key */
+			    copy_key (B_PRIGHT_DELIM_KEY (tb->L[0]), B_N_PKEY(tbS0, 0));   
+			    /* probably not needed as something has been shifted to tb->L[0] already */
+			    reiserfs_mark_buffer_dirty (tb->L[0], 0);
+#endif
+			}
+		    }
+		    tb->insert_size[0] = 0;
+		}
+	    } else { /* regular object */
+		if ( pos_in_item == pasted->ih_item_len ) {
+
+#ifdef CONFIG_REISERFS_CHECK
+		    if ( tb->insert_size[0] <= 0 )
+			reiserfs_panic (tb->tb_sb,
+					"PAP-12275: balance_leaf: insert size must not be %d", tb->insert_size[0]);
+#endif /* CONFIG_REISERFS_CHECK */
+		    bi.tb = tb;
+		    bi.bi_bh = tbS0;
+		    bi.bi_parent = PATH_H_PPARENT (tb->tb_path, 0);
+		    bi.bi_position = PATH_H_POSITION (tb->tb_path, 1);
+		    leaf_paste_in_buffer (&bi, item_pos, pos_in_item, tb->insert_size[0], body, zeros_num);
+
+		    if (is_indirect_le_ih (pasted)) {
+
+#ifdef CONFIG_REISERFS_CHECK
+			if ( tb->insert_size[0] != UNFM_P_SIZE )
+			    reiserfs_panic (tb->tb_sb,
+					    "PAP-12280: balance_leaf: insert_size for indirect item must be %d, not %d",
+					    UNFM_P_SIZE, tb->insert_size[0]);
+#endif /* CONFIG_REISERFS_CHECK */
+
+			set_ih_free_space (pasted, ((struct unfm_nodeinfo*)body)->unfm_freespace);
+		    }
+		    tb->insert_size[0] = 0;
+		}
+
+#ifdef CONFIG_REISERFS_CHECK
+		else {
+		    if ( tb->insert_size[0] ) {
+			print_cur_tb ("12285");
+			reiserfs_panic (tb->tb_sb, "PAP-12285: balance_leaf: insert_size must be 0 (%d)", tb->insert_size[0]);
+		    }
+		}
+#endif /* CONFIG_REISERFS_CHECK */
+	    
+	    }
+	} /* case M_PASTE: */
+	}
+    }
+
+#ifdef CONFIG_REISERFS_CHECK
+    if ( flag == M_PASTE && tb->insert_size[0] ) {
+	print_cur_tb ("12290");
+	reiserfs_panic (tb->tb_sb, "PAP-12290: balance_leaf: insert_size is still not 0 (%d)", tb->insert_size[0]);
+    }
+#endif /* CONFIG_REISERFS_CHECK */
+
+    return 0;
+} /* Leaf level of the tree is balanced (end of balance_leaf) */
+
+
+
+/* Make empty node */
+void make_empty_node (struct buffer_info * bi)
+{
+    struct block_head * blkh;
+
+#ifdef CONFIG_REISERFS_CHECK
+    if (bi->bi_bh == NULL)
+	reiserfs_panic (0, "PAP-12295: make_empty_node: pointer to the buffer is NULL");
+#endif
+
+    (blkh = B_BLK_HEAD(bi->bi_bh))->blk_nr_item = cpu_to_le16 (0);
+    blkh->blk_free_space = cpu_to_le16 (MAX_CHILD_SIZE(bi->bi_bh));
+
+    if (bi->bi_parent)
+	B_N_CHILD (bi->bi_parent, bi->bi_position)->dc_size = 0; 
+}
+
+
+/* Get first empty buffer */
+struct buffer_head * get_FEB (struct tree_balance * tb)
+{
+    int i;
+    struct buffer_head * first_b;
+    struct buffer_info bi;
+
+    for (i = 0; i < MAX_FEB_SIZE; i ++)
+	if (tb->FEB[i] != 0)
+	    break;
+
+    if (i == MAX_FEB_SIZE)
+	reiserfs_panic(tb->tb_sb, "vs-12300: get_FEB: FEB list is empty");
+
+    bi.tb = tb;
+    bi.bi_bh = first_b = tb->FEB[i];
+    bi.bi_parent = 0;
+    bi.bi_position = 0;
+    make_empty_node (&bi);
+    set_bit(BH_Uptodate, &first_b->b_state);
+    tb->FEB[i] = 0;
+    tb->used[i] = first_b;
+
+#ifdef REISERFS_FSCK
+    mark_block_formatted (first_b->b_blocknr);
+#endif
+
+    return(first_b);
+}
+
+
+/* This is now used because reiserfs_free_block has to be able to
+** schedule.
+*/
+static void store_thrown (struct tree_balance * tb, struct buffer_head * bh)
+{
+    int i;
+
+    if (buffer_dirty (bh))
+      printk ("store_thrown deals with dirty buffer\n");
+    for (i = 0; i < sizeof (tb->thrown)/sizeof (tb->thrown[0]); i ++)
+	if (!tb->thrown[i]) {
+	    tb->thrown[i] = bh;
+	    atomic_inc(&bh->b_count) ; /* decremented in free_thrown */
+	    return;
+	}
+    reiserfs_warning ("store_thrown: too many thrown buffers\n");
+}
+
+static void free_thrown(struct tree_balance *tb) {
+    int i ;
+    unsigned long blocknr ;
+    for (i = 0; i < sizeof (tb->thrown)/sizeof (tb->thrown[0]); i++) {
+	if (tb->thrown[i]) {
+	    blocknr = tb->thrown[i]->b_blocknr ;
+	    if (buffer_dirty (tb->thrown[i]))
+	      printk ("free_thrown deals with dirty buffer %ld\n", blocknr);
+	    brelse(tb->thrown[i]) ; /* incremented in store_thrown */
+	    reiserfs_free_block (tb->transaction_handle, blocknr);
+	}
+    }
+}
+
+void reiserfs_invalidate_buffer (struct tree_balance * tb, struct buffer_head * bh)
+{
+    B_BLK_HEAD (bh)->blk_level = cpu_to_le16 (FREE_LEVEL)/*0*/;
+    B_BLK_HEAD (bh)->blk_nr_item = cpu_to_le16 (0);
+    mark_buffer_clean (bh);
+    /* reiserfs_free_block is no longer schedule safe 
+    reiserfs_free_block (tb->transaction_handle, tb->tb_sb, bh->b_blocknr);
+    */
+
+    store_thrown (tb, bh);
+#if 0
+#ifdef REISERFS_FSCK
+    {
+	struct buffer_head * to_be_forgotten;
+	
+	to_be_forgotten = find_buffer (bh->b_dev, bh->b_blocknr, bh->b_size);
+	if (to_be_forgotten) {
+	    to_be_forgotten->b_count ++;
+	    bforget (to_be_forgotten);
+	}
+	unmark_block_formatted (bh->b_blocknr);
+    }
+#endif
+#endif
+}
+
+/* Replace n_dest'th key in buffer dest by n_src'th key of buffer src.*/
+void replace_key (struct tree_balance * tb, struct buffer_head * dest, int n_dest,
+		  struct buffer_head * src, int n_src)
+{
+
+#ifdef CONFIG_REISERFS_CHECK
+    if (dest == NULL || src == NULL)
+	reiserfs_panic (0, "vs-12305: replace_key: sourse or destination buffer is 0 (src=%p, dest=%p)", src, dest);
+
+    if ( ! B_IS_KEYS_LEVEL (dest) )
+	reiserfs_panic (0, "vs-12310: replace_key: invalid level (%z) for destination buffer. dest must be leaf",
+			dest);
+
+    if (n_dest < 0 || n_src < 0)
+	reiserfs_panic (0, "vs-12315: replace_key: src(%d) or dest(%d) key number less than 0", n_src, n_dest);
+
+    if (n_dest >= B_NR_ITEMS(dest) || n_src >= B_NR_ITEMS(src))
+	reiserfs_panic (0, "vs-12320: replace_key: src(%d(%d)) or dest(%d(%d)) key number is too big",
+			n_src, B_NR_ITEMS(src), n_dest, B_NR_ITEMS(dest));
+#endif	/* CONFIG_REISERFS_CHECK */
+   
+    if (B_IS_ITEMS_LEVEL (src))
+	/* source buffer contains leaf node */
+	memcpy (B_N_PDELIM_KEY(dest,n_dest), B_N_PITEM_HEAD(src,n_src), KEY_SIZE);
+    else
+	memcpy (B_N_PDELIM_KEY(dest,n_dest), B_N_PDELIM_KEY(src,n_src), KEY_SIZE);
+
+    do_balance_mark_internal_dirty (tb, dest, 0);
+}
+
+
+int get_left_neighbor_position (
+				struct tree_balance * tb, 
+				int h
+				)
+{
+  int Sh_position = PATH_H_POSITION (tb->tb_path, h + 1);
+
+#ifdef CONFIG_REISERFS_CHECK
+  if (PATH_H_PPARENT (tb->tb_path, h) == 0 || tb->FL[h] == 0)
+    reiserfs_panic (tb->tb_sb, "vs-12325: get_left_neighbor_position: FL[%d](%p) or F[%d](%p) does not exist", 
+		    h, tb->FL[h], h, PATH_H_PPARENT (tb->tb_path, h));
+#endif
+
+  if (Sh_position == 0)
+    return B_NR_ITEMS (tb->FL[h]);
+  else
+    return Sh_position - 1;
+}
+
+
+int get_right_neighbor_position (struct tree_balance * tb, int h)
+{
+  int Sh_position = PATH_H_POSITION (tb->tb_path, h + 1);
+
+#ifdef CONFIG_REISERFS_CHECK
+  if (PATH_H_PPARENT (tb->tb_path, h) == 0 || tb->FR[h] == 0)
+    reiserfs_panic (tb->tb_sb, "vs-12330: get_right_neighbor_position: F[%d](%p) or FR[%d](%p) does not exist", 
+		    h, PATH_H_PPARENT (tb->tb_path, h), h, tb->FR[h]);
+#endif
+
+  if (Sh_position == B_NR_ITEMS (PATH_H_PPARENT (tb->tb_path, h)))
+    return 0;
+  else
+    return Sh_position + 1;
+}
+
+
+#ifdef CONFIG_REISERFS_CHECK
+
+int is_reusable (struct super_block * s, unsigned long block, int bit_value);
+static void check_internal_node (struct super_block * s, struct buffer_head * bh, char * mes)
+{
+  struct disk_child * dc;
+  int i;
+
+  if (!bh)
+    reiserfs_panic (s, "PAP-12336: check_internal_node: bh == 0");
+
+  if (!bh || !B_IS_IN_TREE (bh))
+    return;
+ 
+  if (!buffer_dirty (bh) && 
+      !(buffer_journaled(bh) || buffer_journal_dirty(bh))) {
+    reiserfs_panic (s, "PAP-12337: check_internal_node: buffer (%b) must be dirty", bh);
+  }
+
+  dc = B_N_CHILD (bh, 0);
+
+  for (i = 0; i <= B_NR_ITEMS (bh); i ++, dc ++) {
+    if (!is_reusable (s, dc->dc_block_number, 1) ) {
+      print_cur_tb (mes);
+      reiserfs_panic (s, "PAP-12338: check_internal_node: invalid child pointer %y in %b", dc, bh);
+    }
+  }
+}
+
+
+static int locked_or_not_in_tree (struct buffer_head * bh, char * which)
+{
+  if ( buffer_locked (bh) || !B_IS_IN_TREE (bh) ) {
+    reiserfs_warning ("vs-12339: locked_or_not_in_tree: %s (%b)\n", which, bh);
+    return 1;
+  } 
+  return 0;
+}
+
+
+static int check_before_balancing (struct tree_balance * tb)
+{
+  int retval = 0;	
+
+  if ( cur_tb ) {
+    reiserfs_panic (tb->tb_sb, "vs-12335: check_before_balancing: "
+		    "suspect that schedule occurred based on cur_tb not being null at this point in code. "
+		    "do_balance cannot properly handle schedule occuring while it runs.");
+  }
+  
+  /* double check that buffers that we will modify are unlocked. (fix_nodes should already have
+     prepped all of these for us). */
+  if ( tb->lnum[0] ) {
+    retval |= locked_or_not_in_tree (tb->L[0], "L[0]");
+    retval |= locked_or_not_in_tree (tb->FL[0], "FL[0]");
+    retval |= locked_or_not_in_tree (tb->CFL[0], "CFL[0]");
+    check_leaf (tb->L[0]);
+  }
+  if ( tb->rnum[0] ) {
+    retval |= locked_or_not_in_tree (tb->R[0], "R[0]");
+    retval |= locked_or_not_in_tree (tb->FR[0], "FR[0]");
+    retval |= locked_or_not_in_tree (tb->CFR[0], "CFR[0]");
+    check_leaf (tb->R[0]);
+  }
+  retval |= locked_or_not_in_tree (PATH_PLAST_BUFFER (tb->tb_path), "S[0]");
+  check_leaf (PATH_PLAST_BUFFER (tb->tb_path));
+
+  return retval;
+}
+
+
+void check_after_balance_leaf (struct tree_balance * tb)
+{
+    if (tb->lnum[0]) {
+	if (B_FREE_SPACE (tb->L[0]) != 
+	    MAX_CHILD_SIZE (tb->L[0]) - B_N_CHILD (tb->FL[0], get_left_neighbor_position (tb, 0))->dc_size) {
+	    print_cur_tb ("12221");
+	    reiserfs_panic (tb->tb_sb, "PAP-12355: check_after_balance_leaf: shift to left was incorrect");
+	}
+    }
+    if (tb->rnum[0]) {
+	if (B_FREE_SPACE (tb->R[0]) != 
+	    MAX_CHILD_SIZE (tb->R[0]) - B_N_CHILD (tb->FR[0], get_right_neighbor_position (tb, 0))->dc_size) {
+	    print_cur_tb ("12222");
+	    reiserfs_panic (tb->tb_sb, "PAP-12360: check_after_balance_leaf: shift to right was incorrect");
+	}
+    }
+    if (PATH_H_PBUFFER(tb->tb_path,1) && (B_FREE_SPACE (PATH_H_PBUFFER(tb->tb_path,0)) != 
+					  (MAX_CHILD_SIZE (PATH_H_PBUFFER(tb->tb_path,0)) -
+					   B_N_CHILD (PATH_H_PBUFFER(tb->tb_path,1),
+						      PATH_H_POSITION (tb->tb_path, 1))->dc_size))) {
+	print_cur_tb ("12223");
+	reiserfs_panic (tb->tb_sb, "PAP-12365: check_after_balance_leaf: S is incorrect");
+    }
+}
+
+
+void check_leaf_level (struct tree_balance * tb)
+{
+  check_leaf (tb->L[0]);
+  check_leaf (tb->R[0]);
+  check_leaf (PATH_PLAST_BUFFER (tb->tb_path));
+}
+
+void check_internal_levels (struct tree_balance * tb)
+{
+  int h;
+
+  /* check all internal nodes */
+  for (h = 1; tb->insert_size[h]; h ++) {
+    check_internal_node (tb->tb_sb, PATH_H_PBUFFER (tb->tb_path, h), "BAD BUFFER ON PATH");
+    if (tb->lnum[h])
+      check_internal_node (tb->tb_sb, tb->L[h], "BAD L");
+    if (tb->rnum[h])
+      check_internal_node (tb->tb_sb, tb->R[h], "BAD R");
+  }
+
+}
+
+#endif
+
+
+
+
+
+
+/* Now we have all of the buffers that must be used in balancing of
+   the tree.  We rely on the assumption that schedule() will not occur
+   while do_balance works. ( Only interrupt handlers are acceptable.)
+   We balance the tree according to the analysis made before this,
+   using buffers already obtained.  For SMP support it will someday be
+   necessary to add ordered locking of tb. */
+
+/* Some interesting rules of balancing:
+
+   we delete a maximum of two nodes per level per balancing: we never
+   delete R, when we delete two of three nodes L, S, R then we move
+   them into R.
+
+   we only delete L if we are deleting two nodes, if we delete only
+   one node we delete S
+
+   if we shift leaves then we shift as much as we can: this is a
+   deliberate policy of extremism in node packing which results in
+   higher average utilization after repeated random balance operations
+   at the cost of more memory copies and more balancing as a result of
+   small insertions to full nodes.
+
+   if we shift internal nodes we try to evenly balance the node
+   utilization, with consequent less balancing at the cost of lower
+   utilization.
+
+   one could argue that the policy for directories in leaves should be
+   that of internal nodes, but we will wait until another day to
+   evaluate this....  It would be nice to someday measure and prove
+   these assumptions as to what is optimal....
+
+*/
+
+static inline void do_balance_starts (struct tree_balance *tb)
+{
+    /* use print_cur_tb() to see initial state of struct
+       tree_balance */
+
+    /* store_print_tb (tb); */
+
+#ifdef CONFIG_REISERFS_CHECK
+
+    /* do not delete, just comment it out */
+/*    print_tb(flag, PATH_LAST_POSITION(tb->tb_path), tb->tb_path->pos_in_item, tb, 
+	     "check");*/
+
+    if (check_before_balancing (tb))
+	reiserfs_panic (tb->tb_sb, "PAP-12340: do_balance: locked buffers in TB");
+
+#ifndef __KERNEL__
+    if ( atomic_read(&(PATH_PLAST_BUFFER(tb->tb_path)->b_count)) > 1 || (tb->L[0] && atomic_read(&(tb->L[0]->b_count)) > 1) ||
+	 (tb->R[0] && atomic_read(&(tb->R[0]->b_count)) > 1) ) {
+	print_cur_tb ("first three parameters are invalid");
+	reiserfs_panic (tb->tb_sb, "PAP-12345: do_balance: counter too big");
+    }
+#endif /* !__KERNEL__ */
+    cur_tb = tb;
+    
+#endif /* CONFIG_REISERFS_CHECK */
+}
+
+
+static inline void do_balance_completed (struct tree_balance * tb)
+{
+    
+#ifdef CONFIG_REISERFS_CHECK
+    check_leaf_level (tb);
+    check_internal_levels (tb);
+    cur_tb = NULL;
+#endif
+
+    /* reiserfs_free_block is no longer schedule safe.  So, we need to
+    ** put the buffers we want freed on the thrown list during do_balance,
+    ** and then free them now
+    */
+
+    tb->tb_sb->u.reiserfs_sb.s_do_balance ++;
+
+
+    /* release all nodes hold to perform the balancing */
+    unfix_nodes(tb);
+
+    free_thrown(tb) ;
+}
+
+
+
+
+
+void do_balance (struct tree_balance * tb, /* tree_balance structure */
+		 struct item_head * ih,	   /* item header of inserted item */
+		 const char * body,  /* body  of inserted item or bytes to paste */
+		 int flag)  /* i - insert, d - delete
+			       c - cut, p - paste
+						      
+			       Cut means delete part of an item
+			       (includes removing an entry from a
+			       directory).
+						      
+			       Delete means delete whole item.
+						      
+			       Insert means add a new item into the
+			       tree.
+						      						      
+			       Paste means to append to the end of an
+			       existing file or to insert a directory
+			       entry.  */
+{
+    int child_pos,					/* position of a child node in its parent */
+	h;								/* level of the tree being processed */
+    struct item_head insert_key[2]; /* in our processing of one level
+				       we sometimes determine what
+				       must be inserted into the next
+				       higher level.  This insertion
+				       consists of a key or two keys
+				       and their corresponding
+				       pointers */
+    struct buffer_head *insert_ptr[2]; /* inserted node-ptrs for the next
+					  level */
+
+    tb->tb_mode = flag;
+    tb->need_balance_dirty = 0;
+
+    if (FILESYSTEM_CHANGED_TB(tb)) {
+        reiserfs_panic(tb->tb_sb, "clm-6000: do_balance, fs generation has changed\n") ;
+    }
+    /* if we have no real work to do  */
+    if ( ! tb->insert_size[0] ) {
+	reiserfs_warning ("PAP-12350: do_balance: insert_size == 0, mode == %c",
+			  flag);
+	unfix_nodes(tb);
+	return;
+    }
+
+    atomic_inc (&(fs_generation (tb->tb_sb)));
+    do_balance_starts (tb);
+    
+#ifdef REISERFS_FSCK
+    if (flag == M_INTERNAL) {
+	insert_ptr[0] = (struct buffer_head *)body;
+	/* we must prepare insert_key */
+
+	if (PATH_H_B_ITEM_ORDER (tb->tb_path, 0)/*LAST_POSITION (tb->tb_path)*//*item_pos*/ == -1) {
+		/* get delimiting key from buffer in tree */
+		copy_key (&insert_key[0].ih_key, B_N_PKEY (PATH_PLAST_BUFFER (tb->tb_path), 0));
+		/*insert_ptr[0]->b_item_order = 0;*/
+	} else {
+	    /* get delimiting key from new buffer */
+	    copy_key (&insert_key[0].ih_key, B_N_PKEY((struct buffer_head *)body,0));
+	    /*insert_ptr[0]->b_item_order = item_pos;*/
+	}
+      
+	/* and insert_ptr instead of balance_leaf */
+	child_pos = PATH_H_B_ITEM_ORDER (tb->tb_path, 0)/*item_pos*/;
+    } else
+#endif
+
+	/* balance leaf returns 0 except if combining L R and S into
+	   one node.  see balance_internal() for explanation of this
+	   line of code.*/
+	child_pos = PATH_H_B_ITEM_ORDER (tb->tb_path, 0) +
+	  balance_leaf (tb, ih, body, flag, insert_key, insert_ptr);
+
+#ifdef CONFIG_REISERFS_CHECK
+    check_after_balance_leaf (tb);
+#endif
+
+    /* Balance internal level of the tree. */
+    for ( h = 1; h < MAX_HEIGHT && tb->insert_size[h]; h++ )
+	child_pos = balance_internal (tb, h, child_pos, insert_key, insert_ptr);
+
+
+    do_balance_completed (tb);
+
+}

FUNET's LINUX-ADM group, linux-adm@nic.funet.fi
TCL-scripts by Sam Shen (who was at: slshen@lbl.gov)