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, 2648 insertions, 0 deletions

diff --git a/fs/xfs/xfs_da_btree.c b/fs/xfs/xfs_da_btree.c
new file mode 100644
index 00000000000..d7fe2886676
--- /dev/null
+++ b/fs/xfs/xfs_da_btree.c
@@ -0,0 +1,2648 @@
+/*
+ * Copyright (c) 2000-2004 Silicon Graphics, Inc.  All Rights Reserved.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of version 2 of the GNU General Public License as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it would be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
+ *
+ * Further, this software is distributed without any warranty that it is
+ * free of the rightful claim of any third person regarding infringement
+ * or the like.  Any license provided herein, whether implied or
+ * otherwise, applies only to this software file.  Patent licenses, if
+ * any, provided herein do not apply to combinations of this program with
+ * other software, or any other product whatsoever.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, write the Free Software Foundation, Inc., 59
+ * Temple Place - Suite 330, Boston MA 02111-1307, USA.
+ *
+ * Contact information: Silicon Graphics, Inc., 1600 Amphitheatre Pkwy,
+ * Mountain View, CA  94043, or:
+ *
+ * http://www.sgi.com
+ *
+ * For further information regarding this notice, see:
+ *
+ * http://oss.sgi.com/projects/GenInfo/SGIGPLNoticeExplan/
+ */
+
+#include "xfs.h"
+
+#include "xfs_macros.h"
+#include "xfs_types.h"
+#include "xfs_inum.h"
+#include "xfs_log.h"
+#include "xfs_trans.h"
+#include "xfs_sb.h"
+#include "xfs_ag.h"
+#include "xfs_dir.h"
+#include "xfs_dir2.h"
+#include "xfs_dmapi.h"
+#include "xfs_mount.h"
+#include "xfs_alloc_btree.h"
+#include "xfs_bmap_btree.h"
+#include "xfs_ialloc_btree.h"
+#include "xfs_alloc.h"
+#include "xfs_btree.h"
+#include "xfs_attr_sf.h"
+#include "xfs_dir_sf.h"
+#include "xfs_dir2_sf.h"
+#include "xfs_dinode.h"
+#include "xfs_inode_item.h"
+#include "xfs_inode.h"
+#include "xfs_bmap.h"
+#include "xfs_da_btree.h"
+#include "xfs_attr.h"
+#include "xfs_attr_leaf.h"
+#include "xfs_dir_leaf.h"
+#include "xfs_dir2_data.h"
+#include "xfs_dir2_leaf.h"
+#include "xfs_dir2_block.h"
+#include "xfs_dir2_node.h"
+#include "xfs_error.h"
+#include "xfs_bit.h"
+
+/*
+ * xfs_da_btree.c
+ *
+ * Routines to implement directories as Btrees of hashed names.
+ */
+
+/*========================================================================
+ * Function prototypes for the kernel.
+ *========================================================================*/
+
+/*
+ * Routines used for growing the Btree.
+ */
+STATIC int xfs_da_root_split(xfs_da_state_t *state,
+					    xfs_da_state_blk_t *existing_root,
+					    xfs_da_state_blk_t *new_child);
+STATIC int xfs_da_node_split(xfs_da_state_t *state,
+					    xfs_da_state_blk_t *existing_blk,
+					    xfs_da_state_blk_t *split_blk,
+					    xfs_da_state_blk_t *blk_to_add,
+					    int treelevel,
+					    int *result);
+STATIC void xfs_da_node_rebalance(xfs_da_state_t *state,
+					 xfs_da_state_blk_t *node_blk_1,
+					 xfs_da_state_blk_t *node_blk_2);
+STATIC void xfs_da_node_add(xfs_da_state_t *state,
+				   xfs_da_state_blk_t *old_node_blk,
+				   xfs_da_state_blk_t *new_node_blk);
+
+/*
+ * Routines used for shrinking the Btree.
+ */
+STATIC int xfs_da_root_join(xfs_da_state_t *state,
+					   xfs_da_state_blk_t *root_blk);
+STATIC int xfs_da_node_toosmall(xfs_da_state_t *state, int *retval);
+STATIC void xfs_da_node_remove(xfs_da_state_t *state,
+					      xfs_da_state_blk_t *drop_blk);
+STATIC void xfs_da_node_unbalance(xfs_da_state_t *state,
+					 xfs_da_state_blk_t *src_node_blk,
+					 xfs_da_state_blk_t *dst_node_blk);
+
+/*
+ * Utility routines.
+ */
+STATIC uint	xfs_da_node_lasthash(xfs_dabuf_t *bp, int *count);
+STATIC int	xfs_da_node_order(xfs_dabuf_t *node1_bp, xfs_dabuf_t *node2_bp);
+STATIC xfs_dabuf_t *xfs_da_buf_make(int nbuf, xfs_buf_t **bps, inst_t *ra);
+
+
+/*========================================================================
+ * Routines used for growing the Btree.
+ *========================================================================*/
+
+/*
+ * Create the initial contents of an intermediate node.
+ */
+int
+xfs_da_node_create(xfs_da_args_t *args, xfs_dablk_t blkno, int level,
+				 xfs_dabuf_t **bpp, int whichfork)
+{
+	xfs_da_intnode_t *node;
+	xfs_dabuf_t *bp;
+	int error;
+	xfs_trans_t *tp;
+
+	tp = args->trans;
+	error = xfs_da_get_buf(tp, args->dp, blkno, -1, &bp, whichfork);
+	if (error)
+		return(error);
+	ASSERT(bp != NULL);
+	node = bp->data;
+	node->hdr.info.forw = 0;
+	node->hdr.info.back = 0;
+	INT_SET(node->hdr.info.magic, ARCH_CONVERT, XFS_DA_NODE_MAGIC);
+	node->hdr.info.pad = 0;
+	node->hdr.count = 0;
+	INT_SET(node->hdr.level, ARCH_CONVERT, level);
+
+	xfs_da_log_buf(tp, bp,
+		XFS_DA_LOGRANGE(node, &node->hdr, sizeof(node->hdr)));
+
+	*bpp = bp;
+	return(0);
+}
+
+/*
+ * Split a leaf node, rebalance, then possibly split
+ * intermediate nodes, rebalance, etc.
+ */
+int							/* error */
+xfs_da_split(xfs_da_state_t *state)
+{
+	xfs_da_state_blk_t *oldblk, *newblk, *addblk;
+	xfs_da_intnode_t *node;
+	xfs_dabuf_t *bp;
+	int max, action, error, i;
+
+	/*
+	 * Walk back up the tree splitting/inserting/adjusting as necessary.
+	 * If we need to insert and there isn't room, split the node, then
+	 * decide which fragment to insert the new block from below into.
+	 * Note that we may split the root this way, but we need more fixup.
+	 */
+	max = state->path.active - 1;
+	ASSERT((max >= 0) && (max < XFS_DA_NODE_MAXDEPTH));
+	ASSERT(state->path.blk[max].magic == XFS_ATTR_LEAF_MAGIC ||
+	       state->path.blk[max].magic == XFS_DIRX_LEAF_MAGIC(state->mp));
+
+	addblk = &state->path.blk[max];		/* initial dummy value */
+	for (i = max; (i >= 0) && addblk; state->path.active--, i--) {
+		oldblk = &state->path.blk[i];
+		newblk = &state->altpath.blk[i];
+
+		/*
+		 * If a leaf node then
+		 *     Allocate a new leaf node, then rebalance across them.
+		 * else if an intermediate node then
+		 *     We split on the last layer, must we split the node?
+		 */
+		switch (oldblk->magic) {
+		case XFS_ATTR_LEAF_MAGIC:
+#ifndef __KERNEL__
+			return(ENOTTY);
+#else
+			error = xfs_attr_leaf_split(state, oldblk, newblk);
+			if ((error != 0) && (error != ENOSPC)) {
+				return(error);	/* GROT: attr is inconsistent */
+			}
+			if (!error) {
+				addblk = newblk;
+				break;
+			}
+			/*
+			 * Entry wouldn't fit, split the leaf again.
+			 */
+			state->extravalid = 1;
+			if (state->inleaf) {
+				state->extraafter = 0;	/* before newblk */
+				error = xfs_attr_leaf_split(state, oldblk,
+							    &state->extrablk);
+			} else {
+				state->extraafter = 1;	/* after newblk */
+				error = xfs_attr_leaf_split(state, newblk,
+							    &state->extrablk);
+			}
+			if (error)
+				return(error);	/* GROT: attr inconsistent */
+			addblk = newblk;
+			break;
+#endif
+		case XFS_DIR_LEAF_MAGIC:
+			ASSERT(XFS_DIR_IS_V1(state->mp));
+			error = xfs_dir_leaf_split(state, oldblk, newblk);
+			if ((error != 0) && (error != ENOSPC)) {
+				return(error);	/* GROT: dir is inconsistent */
+			}
+			if (!error) {
+				addblk = newblk;
+				break;
+			}
+			/*
+			 * Entry wouldn't fit, split the leaf again.
+			 */
+			state->extravalid = 1;
+			if (state->inleaf) {
+				state->extraafter = 0;	/* before newblk */
+				error = xfs_dir_leaf_split(state, oldblk,
+							   &state->extrablk);
+				if (error)
+					return(error);	/* GROT: dir incon. */
+				addblk = newblk;
+			} else {
+				state->extraafter = 1;	/* after newblk */
+				error = xfs_dir_leaf_split(state, newblk,
+							   &state->extrablk);
+				if (error)
+					return(error);	/* GROT: dir incon. */
+				addblk = newblk;
+			}
+			break;
+		case XFS_DIR2_LEAFN_MAGIC:
+			ASSERT(XFS_DIR_IS_V2(state->mp));
+			error = xfs_dir2_leafn_split(state, oldblk, newblk);
+			if (error)
+				return error;
+			addblk = newblk;
+			break;
+		case XFS_DA_NODE_MAGIC:
+			error = xfs_da_node_split(state, oldblk, newblk, addblk,
+							 max - i, &action);
+			xfs_da_buf_done(addblk->bp);
+			addblk->bp = NULL;
+			if (error)
+				return(error);	/* GROT: dir is inconsistent */
+			/*
+			 * Record the newly split block for the next time thru?
+			 */
+			if (action)
+				addblk = newblk;
+			else
+				addblk = NULL;
+			break;
+		}
+
+		/*
+		 * Update the btree to show the new hashval for this child.
+		 */
+		xfs_da_fixhashpath(state, &state->path);
+		/*
+		 * If we won't need this block again, it's getting dropped
+		 * from the active path by the loop control, so we need
+		 * to mark it done now.
+		 */
+		if (i > 0 || !addblk)
+			xfs_da_buf_done(oldblk->bp);
+	}
+	if (!addblk)
+		return(0);
+
+	/*
+	 * Split the root node.
+	 */
+	ASSERT(state->path.active == 0);
+	oldblk = &state->path.blk[0];
+	error = xfs_da_root_split(state, oldblk, addblk);
+	if (error) {
+		xfs_da_buf_done(oldblk->bp);
+		xfs_da_buf_done(addblk->bp);
+		addblk->bp = NULL;
+		return(error);	/* GROT: dir is inconsistent */
+	}
+
+	/*
+	 * Update pointers to the node which used to be block 0 and
+	 * just got bumped because of the addition of a new root node.
+	 * There might be three blocks involved if a double split occurred,
+	 * and the original block 0 could be at any position in the list.
+	 */
+
+	node = oldblk->bp->data;
+	if (node->hdr.info.forw) {
+		if (INT_GET(node->hdr.info.forw, ARCH_CONVERT) == addblk->blkno) {
+			bp = addblk->bp;
+		} else {
+			ASSERT(state->extravalid);
+			bp = state->extrablk.bp;
+		}
+		node = bp->data;
+		INT_SET(node->hdr.info.back, ARCH_CONVERT, oldblk->blkno);
+		xfs_da_log_buf(state->args->trans, bp,
+		    XFS_DA_LOGRANGE(node, &node->hdr.info,
+		    sizeof(node->hdr.info)));
+	}
+	node = oldblk->bp->data;
+	if (INT_GET(node->hdr.info.back, ARCH_CONVERT)) {
+		if (INT_GET(node->hdr.info.back, ARCH_CONVERT) == addblk->blkno) {
+			bp = addblk->bp;
+		} else {
+			ASSERT(state->extravalid);
+			bp = state->extrablk.bp;
+		}
+		node = bp->data;
+		INT_SET(node->hdr.info.forw, ARCH_CONVERT, oldblk->blkno);
+		xfs_da_log_buf(state->args->trans, bp,
+		    XFS_DA_LOGRANGE(node, &node->hdr.info,
+		    sizeof(node->hdr.info)));
+	}
+	xfs_da_buf_done(oldblk->bp);
+	xfs_da_buf_done(addblk->bp);
+	addblk->bp = NULL;
+	return(0);
+}
+
+/*
+ * Split the root.  We have to create a new root and point to the two
+ * parts (the split old root) that we just created.  Copy block zero to
+ * the EOF, extending the inode in process.
+ */
+STATIC int						/* error */
+xfs_da_root_split(xfs_da_state_t *state, xfs_da_state_blk_t *blk1,
+				 xfs_da_state_blk_t *blk2)
+{
+	xfs_da_intnode_t *node, *oldroot;
+	xfs_da_args_t *args;
+	xfs_dablk_t blkno;
+	xfs_dabuf_t *bp;
+	int error, size;
+	xfs_inode_t *dp;
+	xfs_trans_t *tp;
+	xfs_mount_t *mp;
+	xfs_dir2_leaf_t *leaf;
+
+	/*
+	 * Copy the existing (incorrect) block from the root node position
+	 * to a free space somewhere.
+	 */
+	args = state->args;
+	ASSERT(args != NULL);
+	error = xfs_da_grow_inode(args, &blkno);
+	if (error)
+		return(error);
+	dp = args->dp;
+	tp = args->trans;
+	mp = state->mp;
+	error = xfs_da_get_buf(tp, dp, blkno, -1, &bp, args->whichfork);
+	if (error)
+		return(error);
+	ASSERT(bp != NULL);
+	node = bp->data;
+	oldroot = blk1->bp->data;
+	if (INT_GET(oldroot->hdr.info.magic, ARCH_CONVERT) == XFS_DA_NODE_MAGIC) {
+		size = (int)((char *)&oldroot->btree[INT_GET(oldroot->hdr.count, ARCH_CONVERT)] -
+			     (char *)oldroot);
+	} else {
+		ASSERT(XFS_DIR_IS_V2(mp));
+		ASSERT(INT_GET(oldroot->hdr.info.magic, ARCH_CONVERT) == XFS_DIR2_LEAFN_MAGIC);
+		leaf = (xfs_dir2_leaf_t *)oldroot;
+		size = (int)((char *)&leaf->ents[INT_GET(leaf->hdr.count, ARCH_CONVERT)] -
+			     (char *)leaf);
+	}
+	memcpy(node, oldroot, size);
+	xfs_da_log_buf(tp, bp, 0, size - 1);
+	xfs_da_buf_done(blk1->bp);
+	blk1->bp = bp;
+	blk1->blkno = blkno;
+
+	/*
+	 * Set up the new root node.
+	 */
+	error = xfs_da_node_create(args,
+		args->whichfork == XFS_DATA_FORK &&
+		XFS_DIR_IS_V2(mp) ? mp->m_dirleafblk : 0,
+		INT_GET(node->hdr.level, ARCH_CONVERT) + 1, &bp, args->whichfork);
+	if (error)
+		return(error);
+	node = bp->data;
+	INT_SET(node->btree[0].hashval, ARCH_CONVERT, blk1->hashval);
+	INT_SET(node->btree[0].before, ARCH_CONVERT, blk1->blkno);
+	INT_SET(node->btree[1].hashval, ARCH_CONVERT, blk2->hashval);
+	INT_SET(node->btree[1].before, ARCH_CONVERT, blk2->blkno);
+	INT_SET(node->hdr.count, ARCH_CONVERT, 2);
+
+#ifdef DEBUG
+	if (INT_GET(oldroot->hdr.info.magic, ARCH_CONVERT) == XFS_DIR2_LEAFN_MAGIC) {
+		ASSERT(blk1->blkno >= mp->m_dirleafblk &&
+		       blk1->blkno < mp->m_dirfreeblk);
+		ASSERT(blk2->blkno >= mp->m_dirleafblk &&
+		       blk2->blkno < mp->m_dirfreeblk);
+	}
+#endif
+
+	/* Header is already logged by xfs_da_node_create */
+	xfs_da_log_buf(tp, bp,
+		XFS_DA_LOGRANGE(node, node->btree,
+			sizeof(xfs_da_node_entry_t) * 2));
+	xfs_da_buf_done(bp);
+
+	return(0);
+}
+
+/*
+ * Split the node, rebalance, then add the new entry.
+ */
+STATIC int						/* error */
+xfs_da_node_split(xfs_da_state_t *state, xfs_da_state_blk_t *oldblk,
+				 xfs_da_state_blk_t *newblk,
+				 xfs_da_state_blk_t *addblk,
+				 int treelevel, int *result)
+{
+	xfs_da_intnode_t *node;
+	xfs_dablk_t blkno;
+	int newcount, error;
+	int useextra;
+
+	node = oldblk->bp->data;
+	ASSERT(INT_GET(node->hdr.info.magic, ARCH_CONVERT) == XFS_DA_NODE_MAGIC);
+
+	/*
+	 * With V2 the extra block is data or freespace.
+	 */
+	useextra = state->extravalid && XFS_DIR_IS_V1(state->mp);
+	newcount = 1 + useextra;
+	/*
+	 * Do we have to split the node?
+	 */
+	if ((INT_GET(node->hdr.count, ARCH_CONVERT) + newcount) > state->node_ents) {
+		/*
+		 * Allocate a new node, add to the doubly linked chain of
+		 * nodes, then move some of our excess entries into it.
+		 */
+		error = xfs_da_grow_inode(state->args, &blkno);
+		if (error)
+			return(error);	/* GROT: dir is inconsistent */
+
+		error = xfs_da_node_create(state->args, blkno, treelevel,
+					   &newblk->bp, state->args->whichfork);
+		if (error)
+			return(error);	/* GROT: dir is inconsistent */
+		newblk->blkno = blkno;
+		newblk->magic = XFS_DA_NODE_MAGIC;
+		xfs_da_node_rebalance(state, oldblk, newblk);
+		error = xfs_da_blk_link(state, oldblk, newblk);
+		if (error)
+			return(error);
+		*result = 1;
+	} else {
+		*result = 0;
+	}
+
+	/*
+	 * Insert the new entry(s) into the correct block
+	 * (updating last hashval in the process).
+	 *
+	 * xfs_da_node_add() inserts BEFORE the given index,
+	 * and as a result of using node_lookup_int() we always
+	 * point to a valid entry (not after one), but a split
+	 * operation always results in a new block whose hashvals
+	 * FOLLOW the current block.
+	 *
+	 * If we had double-split op below us, then add the extra block too.
+	 */
+	node = oldblk->bp->data;
+	if (oldblk->index <= INT_GET(node->hdr.count, ARCH_CONVERT)) {
+		oldblk->index++;
+		xfs_da_node_add(state, oldblk, addblk);
+		if (useextra) {
+			if (state->extraafter)
+				oldblk->index++;
+			xfs_da_node_add(state, oldblk, &state->extrablk);
+			state->extravalid = 0;
+		}
+	} else {
+		newblk->index++;
+		xfs_da_node_add(state, newblk, addblk);
+		if (useextra) {
+			if (state->extraafter)
+				newblk->index++;
+			xfs_da_node_add(state, newblk, &state->extrablk);
+			state->extravalid = 0;
+		}
+	}
+
+	return(0);
+}
+
+/*
+ * Balance the btree elements between two intermediate nodes,
+ * usually one full and one empty.
+ *
+ * NOTE: if blk2 is empty, then it will get the upper half of blk1.
+ */
+STATIC void
+xfs_da_node_rebalance(xfs_da_state_t *state, xfs_da_state_blk_t *blk1,
+				     xfs_da_state_blk_t *blk2)
+{
+	xfs_da_intnode_t *node1, *node2, *tmpnode;
+	xfs_da_node_entry_t *btree_s, *btree_d;
+	int count, tmp;
+	xfs_trans_t *tp;
+
+	node1 = blk1->bp->data;
+	node2 = blk2->bp->data;
+	/*
+	 * Figure out how many entries need to move, and in which direction.
+	 * Swap the nodes around if that makes it simpler.
+	 */
+	if ((INT_GET(node1->hdr.count, ARCH_CONVERT) > 0) && (INT_GET(node2->hdr.count, ARCH_CONVERT) > 0) &&
+	    ((INT_GET(node2->btree[ 0 ].hashval, ARCH_CONVERT) < INT_GET(node1->btree[ 0 ].hashval, ARCH_CONVERT)) ||
+	     (INT_GET(node2->btree[ INT_GET(node2->hdr.count, ARCH_CONVERT)-1 ].hashval, ARCH_CONVERT) <
+	      INT_GET(node1->btree[ INT_GET(node1->hdr.count, ARCH_CONVERT)-1 ].hashval, ARCH_CONVERT)))) {
+		tmpnode = node1;
+		node1 = node2;
+		node2 = tmpnode;
+	}
+	ASSERT(INT_GET(node1->hdr.info.magic, ARCH_CONVERT) == XFS_DA_NODE_MAGIC);
+	ASSERT(INT_GET(node2->hdr.info.magic, ARCH_CONVERT) == XFS_DA_NODE_MAGIC);
+	count = (INT_GET(node1->hdr.count, ARCH_CONVERT) - INT_GET(node2->hdr.count, ARCH_CONVERT)) / 2;
+	if (count == 0)
+		return;
+	tp = state->args->trans;
+	/*
+	 * Two cases: high-to-low and low-to-high.
+	 */
+	if (count > 0) {
+		/*
+		 * Move elements in node2 up to make a hole.
+		 */
+		if ((tmp = INT_GET(node2->hdr.count, ARCH_CONVERT)) > 0) {
+			tmp *= (uint)sizeof(xfs_da_node_entry_t);
+			btree_s = &node2->btree[0];
+			btree_d = &node2->btree[count];
+			memmove(btree_d, btree_s, tmp);
+		}
+
+		/*
+		 * Move the req'd B-tree elements from high in node1 to
+		 * low in node2.
+		 */
+		INT_MOD(node2->hdr.count, ARCH_CONVERT, count);
+		tmp = count * (uint)sizeof(xfs_da_node_entry_t);
+		btree_s = &node1->btree[INT_GET(node1->hdr.count, ARCH_CONVERT) - count];
+		btree_d = &node2->btree[0];
+		memcpy(btree_d, btree_s, tmp);
+		INT_MOD(node1->hdr.count, ARCH_CONVERT, -(count));
+
+	} else {
+		/*
+		 * Move the req'd B-tree elements from low in node2 to
+		 * high in node1.
+		 */
+		count = -count;
+		tmp = count * (uint)sizeof(xfs_da_node_entry_t);
+		btree_s = &node2->btree[0];
+		btree_d = &node1->btree[INT_GET(node1->hdr.count, ARCH_CONVERT)];
+		memcpy(btree_d, btree_s, tmp);
+		INT_MOD(node1->hdr.count, ARCH_CONVERT, count);
+		xfs_da_log_buf(tp, blk1->bp,
+			XFS_DA_LOGRANGE(node1, btree_d, tmp));
+
+		/*
+		 * Move elements in node2 down to fill the hole.
+		 */
+		tmp  = INT_GET(node2->hdr.count, ARCH_CONVERT) - count;
+		tmp *= (uint)sizeof(xfs_da_node_entry_t);
+		btree_s = &node2->btree[count];
+		btree_d = &node2->btree[0];
+		memmove(btree_d, btree_s, tmp);
+		INT_MOD(node2->hdr.count, ARCH_CONVERT, -(count));
+	}
+
+	/*
+	 * Log header of node 1 and all current bits of node 2.
+	 */
+	xfs_da_log_buf(tp, blk1->bp,
+		XFS_DA_LOGRANGE(node1, &node1->hdr, sizeof(node1->hdr)));
+	xfs_da_log_buf(tp, blk2->bp,
+		XFS_DA_LOGRANGE(node2, &node2->hdr,
+			sizeof(node2->hdr) +
+			sizeof(node2->btree[0]) * INT_GET(node2->hdr.count, ARCH_CONVERT)));
+
+	/*
+	 * Record the last hashval from each block for upward propagation.
+	 * (note: don't use the swapped node pointers)
+	 */
+	node1 = blk1->bp->data;
+	node2 = blk2->bp->data;
+	blk1->hashval = INT_GET(node1->btree[ INT_GET(node1->hdr.count, ARCH_CONVERT)-1 ].hashval, ARCH_CONVERT);
+	blk2->hashval = INT_GET(node2->btree[ INT_GET(node2->hdr.count, ARCH_CONVERT)-1 ].hashval, ARCH_CONVERT);
+
+	/*
+	 * Adjust the expected index for insertion.
+	 */
+	if (blk1->index >= INT_GET(node1->hdr.count, ARCH_CONVERT)) {
+		blk2->index = blk1->index - INT_GET(node1->hdr.count, ARCH_CONVERT);
+		blk1->index = INT_GET(node1->hdr.count, ARCH_CONVERT) + 1;	/* make it invalid */
+	}
+}
+
+/*
+ * Add a new entry to an intermediate node.
+ */
+STATIC void
+xfs_da_node_add(xfs_da_state_t *state, xfs_da_state_blk_t *oldblk,
+			       xfs_da_state_blk_t *newblk)
+{
+	xfs_da_intnode_t *node;
+	xfs_da_node_entry_t *btree;
+	int tmp;
+	xfs_mount_t *mp;
+
+	node = oldblk->bp->data;
+	mp = state->mp;
+	ASSERT(INT_GET(node->hdr.info.magic, ARCH_CONVERT) == XFS_DA_NODE_MAGIC);
+	ASSERT((oldblk->index >= 0) && (oldblk->index <= INT_GET(node->hdr.count, ARCH_CONVERT)));
+	ASSERT(newblk->blkno != 0);
+	if (state->args->whichfork == XFS_DATA_FORK && XFS_DIR_IS_V2(mp))
+		ASSERT(newblk->blkno >= mp->m_dirleafblk &&
+		       newblk->blkno < mp->m_dirfreeblk);
+
+	/*
+	 * We may need to make some room before we insert the new node.
+	 */
+	tmp = 0;
+	btree = &node->btree[ oldblk->index ];
+	if (oldblk->index < INT_GET(node->hdr.count, ARCH_CONVERT)) {
+		tmp = (INT_GET(node->hdr.count, ARCH_CONVERT) - oldblk->index) * (uint)sizeof(*btree);
+		memmove(btree + 1, btree, tmp);
+	}
+	INT_SET(btree->hashval, ARCH_CONVERT, newblk->hashval);
+	INT_SET(btree->before, ARCH_CONVERT, newblk->blkno);
+	xfs_da_log_buf(state->args->trans, oldblk->bp,
+		XFS_DA_LOGRANGE(node, btree, tmp + sizeof(*btree)));
+	INT_MOD(node->hdr.count, ARCH_CONVERT, +1);
+	xfs_da_log_buf(state->args->trans, oldblk->bp,
+		XFS_DA_LOGRANGE(node, &node->hdr, sizeof(node->hdr)));
+
+	/*
+	 * Copy the last hash value from the oldblk to propagate upwards.
+	 */
+	oldblk->hashval = INT_GET(node->btree[ INT_GET(node->hdr.count, ARCH_CONVERT)-1 ].hashval, ARCH_CONVERT);
+}
+
+/*========================================================================
+ * Routines used for shrinking the Btree.
+ *========================================================================*/
+
+/*
+ * Deallocate an empty leaf node, remove it from its parent,
+ * possibly deallocating that block, etc...
+ */
+int
+xfs_da_join(xfs_da_state_t *state)
+{
+	xfs_da_state_blk_t *drop_blk, *save_blk;
+	int action, error;
+
+	action = 0;
+	drop_blk = &state->path.blk[ state->path.active-1 ];
+	save_blk = &state->altpath.blk[ state->path.active-1 ];
+	ASSERT(state->path.blk[0].magic == XFS_DA_NODE_MAGIC);
+	ASSERT(drop_blk->magic == XFS_ATTR_LEAF_MAGIC ||
+	       drop_blk->magic == XFS_DIRX_LEAF_MAGIC(state->mp));
+
+	/*
+	 * Walk back up the tree joining/deallocating as necessary.
+	 * When we stop dropping blocks, break out.
+	 */
+	for (  ; state->path.active >= 2; drop_blk--, save_blk--,
+		 state->path.active--) {
+		/*
+		 * See if we can combine the block with a neighbor.
+		 *   (action == 0) => no options, just leave
+		 *   (action == 1) => coalesce, then unlink
+		 *   (action == 2) => block empty, unlink it
+		 */
+		switch (drop_blk->magic) {
+		case XFS_ATTR_LEAF_MAGIC:
+#ifndef __KERNEL__
+			error = ENOTTY;
+#else
+			error = xfs_attr_leaf_toosmall(state, &action);
+#endif
+			if (error)
+				return(error);
+			if (action == 0)
+				return(0);
+#ifdef __KERNEL__
+			xfs_attr_leaf_unbalance(state, drop_blk, save_blk);
+#endif
+			break;
+		case XFS_DIR_LEAF_MAGIC:
+			ASSERT(XFS_DIR_IS_V1(state->mp));
+			error = xfs_dir_leaf_toosmall(state, &action);
+			if (error)
+				return(error);
+			if (action == 0)
+				return(0);
+			xfs_dir_leaf_unbalance(state, drop_blk, save_blk);
+			break;
+		case XFS_DIR2_LEAFN_MAGIC:
+			ASSERT(XFS_DIR_IS_V2(state->mp));
+			error = xfs_dir2_leafn_toosmall(state, &action);
+			if (error)
+				return error;
+			if (action == 0)
+				return 0;
+			xfs_dir2_leafn_unbalance(state, drop_blk, save_blk);
+			break;
+		case XFS_DA_NODE_MAGIC:
+			/*
+			 * Remove the offending node, fixup hashvals,
+			 * check for a toosmall neighbor.
+			 */
+			xfs_da_node_remove(state, drop_blk);
+			xfs_da_fixhashpath(state, &state->path);
+			error = xfs_da_node_toosmall(state, &action);
+			if (error)
+				return(error);
+			if (action == 0)
+				return 0;
+			xfs_da_node_unbalance(state, drop_blk, save_blk);
+			break;
+		}
+		xfs_da_fixhashpath(state, &state->altpath);
+		error = xfs_da_blk_unlink(state, drop_blk, save_blk);
+		xfs_da_state_kill_altpath(state);
+		if (error)
+			return(error);
+		error = xfs_da_shrink_inode(state->args, drop_blk->blkno,
+							 drop_blk->bp);
+		drop_blk->bp = NULL;
+		if (error)
+			return(error);
+	}
+	/*
+	 * We joined all the way to the top.  If it turns out that
+	 * we only have one entry in the root, make the child block
+	 * the new root.
+	 */
+	xfs_da_node_remove(state, drop_blk);
+	xfs_da_fixhashpath(state, &state->path);
+	error = xfs_da_root_join(state, &state->path.blk[0]);
+	return(error);
+}
+
+/*
+ * We have only one entry in the root.  Copy the only remaining child of
+ * the old root to block 0 as the new root node.
+ */
+STATIC int
+xfs_da_root_join(xfs_da_state_t *state, xfs_da_state_blk_t *root_blk)
+{
+	xfs_da_intnode_t *oldroot;
+	/* REFERENCED */
+	xfs_da_blkinfo_t *blkinfo;
+	xfs_da_args_t *args;
+	xfs_dablk_t child;
+	xfs_dabuf_t *bp;
+	int error;
+
+	args = state->args;
+	ASSERT(args != NULL);
+	ASSERT(root_blk->magic == XFS_DA_NODE_MAGIC);
+	oldroot = root_blk->bp->data;
+	ASSERT(INT_GET(oldroot->hdr.info.magic, ARCH_CONVERT) == XFS_DA_NODE_MAGIC);
+	ASSERT(!oldroot->hdr.info.forw);
+	ASSERT(!oldroot->hdr.info.back);
+
+	/*
+	 * If the root has more than one child, then don't do anything.
+	 */
+	if (INT_GET(oldroot->hdr.count, ARCH_CONVERT) > 1)
+		return(0);
+
+	/*
+	 * Read in the (only) child block, then copy those bytes into
+	 * the root block's buffer and free the original child block.
+	 */
+	child = INT_GET(oldroot->btree[ 0 ].before, ARCH_CONVERT);
+	ASSERT(child != 0);
+	error = xfs_da_read_buf(args->trans, args->dp, child, -1, &bp,
+					     args->whichfork);
+	if (error)
+		return(error);
+	ASSERT(bp != NULL);
+	blkinfo = bp->data;
+	if (INT_GET(oldroot->hdr.level, ARCH_CONVERT) == 1) {
+		ASSERT(INT_GET(blkinfo->magic, ARCH_CONVERT) == XFS_DIRX_LEAF_MAGIC(state->mp) ||
+		       INT_GET(blkinfo->magic, ARCH_CONVERT) == XFS_ATTR_LEAF_MAGIC);
+	} else {
+		ASSERT(INT_GET(blkinfo->magic, ARCH_CONVERT) == XFS_DA_NODE_MAGIC);
+	}
+	ASSERT(!blkinfo->forw);
+	ASSERT(!blkinfo->back);
+	memcpy(root_blk->bp->data, bp->data, state->blocksize);
+	xfs_da_log_buf(args->trans, root_blk->bp, 0, state->blocksize - 1);
+	error = xfs_da_shrink_inode(args, child, bp);
+	return(error);
+}
+
+/*
+ * Check a node block and its neighbors to see if the block should be
+ * collapsed into one or the other neighbor.  Always keep the block
+ * with the smaller block number.
+ * If the current block is over 50% full, don't try to join it, return 0.
+ * If the block is empty, fill in the state structure and return 2.
+ * If it can be collapsed, fill in the state structure and return 1.
+ * If nothing can be done, return 0.
+ */
+STATIC int
+xfs_da_node_toosmall(xfs_da_state_t *state, int *action)
+{
+	xfs_da_intnode_t *node;
+	xfs_da_state_blk_t *blk;
+	xfs_da_blkinfo_t *info;
+	int count, forward, error, retval, i;
+	xfs_dablk_t blkno;
+	xfs_dabuf_t *bp;
+
+	/*
+	 * Check for the degenerate case of the block being over 50% full.
+	 * If so, it's not worth even looking to see if we might be able
+	 * to coalesce with a sibling.
+	 */
+	blk = &state->path.blk[ state->path.active-1 ];
+	info = blk->bp->data;
+	ASSERT(INT_GET(info->magic, ARCH_CONVERT) == XFS_DA_NODE_MAGIC);
+	node = (xfs_da_intnode_t *)info;
+	count = INT_GET(node->hdr.count, ARCH_CONVERT);
+	if (count > (state->node_ents >> 1)) {
+		*action = 0;	/* blk over 50%, don't try to join */
+		return(0);	/* blk over 50%, don't try to join */
+	}
+
+	/*
+	 * Check for the degenerate case of the block being empty.
+	 * If the block is empty, we'll simply delete it, no need to
+	 * coalesce it with a sibling block.  We choose (aribtrarily)
+	 * to merge with the forward block unless it is NULL.
+	 */
+	if (count == 0) {
+		/*
+		 * Make altpath point to the block we want to keep and
+		 * path point to the block we want to drop (this one).
+		 */
+		forward = info->forw;
+		memcpy(&state->altpath, &state->path, sizeof(state->path));
+		error = xfs_da_path_shift(state, &state->altpath, forward,
+						 0, &retval);
+		if (error)
+			return(error);
+		if (retval) {
+			*action = 0;
+		} else {
+			*action = 2;
+		}
+		return(0);
+	}
+
+	/*
+	 * Examine each sibling block to see if we can coalesce with
+	 * at least 25% free space to spare.  We need to figure out
+	 * whether to merge with the forward or the backward block.
+	 * We prefer coalescing with the lower numbered sibling so as
+	 * to shrink a directory over time.
+	 */
+	/* start with smaller blk num */
+	forward = (INT_GET(info->forw, ARCH_CONVERT)
+				< INT_GET(info->back, ARCH_CONVERT));
+	for (i = 0; i < 2; forward = !forward, i++) {
+		if (forward)
+			blkno = INT_GET(info->forw, ARCH_CONVERT);
+		else
+			blkno = INT_GET(info->back, ARCH_CONVERT);
+		if (blkno == 0)
+			continue;
+		error = xfs_da_read_buf(state->args->trans, state->args->dp,
+					blkno, -1, &bp, state->args->whichfork);
+		if (error)
+			return(error);
+		ASSERT(bp != NULL);
+
+		node = (xfs_da_intnode_t *)info;
+		count  = state->node_ents;
+		count -= state->node_ents >> 2;
+		count -= INT_GET(node->hdr.count, ARCH_CONVERT);
+		node = bp->data;
+		ASSERT(INT_GET(node->hdr.info.magic, ARCH_CONVERT) == XFS_DA_NODE_MAGIC);
+		count -= INT_GET(node->hdr.count, ARCH_CONVERT);
+		xfs_da_brelse(state->args->trans, bp);
+		if (count >= 0)
+			break;	/* fits with at least 25% to spare */
+	}
+	if (i >= 2) {
+		*action = 0;
+		return(0);
+	}
+
+	/*
+	 * Make altpath point to the block we want to keep (the lower
+	 * numbered block) and path point to the block we want to drop.
+	 */
+	memcpy(&state->altpath, &state->path, sizeof(state->path));
+	if (blkno < blk->blkno) {
+		error = xfs_da_path_shift(state, &state->altpath, forward,
+						 0, &retval);
+		if (error) {
+			return(error);
+		}
+		if (retval) {
+			*action = 0;
+			return(0);
+		}
+	} else {
+		error = xfs_da_path_shift(state, &state->path, forward,
+						 0, &retval);
+		if (error) {
+			return(error);
+		}
+		if (retval) {
+			*action = 0;
+			return(0);
+		}
+	}
+	*action = 1;
+	return(0);
+}
+
+/*
+ * Walk back up the tree adjusting hash values as necessary,
+ * when we stop making changes, return.
+ */
+void
+xfs_da_fixhashpath(xfs_da_state_t *state, xfs_da_state_path_t *path)
+{
+	xfs_da_state_blk_t *blk;
+	xfs_da_intnode_t *node;
+	xfs_da_node_entry_t *btree;
+	xfs_dahash_t lasthash=0;
+	int level, count;
+
+	level = path->active-1;
+	blk = &path->blk[ level ];
+	switch (blk->magic) {
+#ifdef __KERNEL__
+	case XFS_ATTR_LEAF_MAGIC:
+		lasthash = xfs_attr_leaf_lasthash(blk->bp, &count);
+		if (count == 0)
+			return;
+		break;
+#endif
+	case XFS_DIR_LEAF_MAGIC:
+		ASSERT(XFS_DIR_IS_V1(state->mp));
+		lasthash = xfs_dir_leaf_lasthash(blk->bp, &count);
+		if (count == 0)
+			return;
+		break;
+	case XFS_DIR2_LEAFN_MAGIC:
+		ASSERT(XFS_DIR_IS_V2(state->mp));
+		lasthash = xfs_dir2_leafn_lasthash(blk->bp, &count);
+		if (count == 0)
+			return;
+		break;
+	case XFS_DA_NODE_MAGIC:
+		lasthash = xfs_da_node_lasthash(blk->bp, &count);
+		if (count == 0)
+			return;
+		break;
+	}
+	for (blk--, level--; level >= 0; blk--, level--) {
+		node = blk->bp->data;
+		ASSERT(INT_GET(node->hdr.info.magic, ARCH_CONVERT) == XFS_DA_NODE_MAGIC);
+		btree = &node->btree[ blk->index ];
+		if (INT_GET(btree->hashval, ARCH_CONVERT) == lasthash)
+			break;
+		blk->hashval = lasthash;
+		INT_SET(btree->hashval, ARCH_CONVERT, lasthash);
+		xfs_da_log_buf(state->args->trans, blk->bp,
+				  XFS_DA_LOGRANGE(node, btree, sizeof(*btree)));
+
+		lasthash = INT_GET(node->btree[ INT_GET(node->hdr.count, ARCH_CONVERT)-1 ].hashval, ARCH_CONVERT);
+	}
+}
+
+/*
+ * Remove an entry from an intermediate node.
+ */
+STATIC void
+xfs_da_node_remove(xfs_da_state_t *state, xfs_da_state_blk_t *drop_blk)
+{
+	xfs_da_intnode_t *node;
+	xfs_da_node_entry_t *btree;
+	int tmp;
+
+	node = drop_blk->bp->data;
+	ASSERT(drop_blk->index < INT_GET(node->hdr.count, ARCH_CONVERT));
+	ASSERT(drop_blk->index >= 0);
+
+	/*
+	 * Copy over the offending entry, or just zero it out.
+	 */
+	btree = &node->btree[drop_blk->index];
+	if (drop_blk->index < (INT_GET(node->hdr.count, ARCH_CONVERT)-1)) {
+		tmp  = INT_GET(node->hdr.count, ARCH_CONVERT) - drop_blk->index - 1;
+		tmp *= (uint)sizeof(xfs_da_node_entry_t);
+		memmove(btree, btree + 1, tmp);
+		xfs_da_log_buf(state->args->trans, drop_blk->bp,
+		    XFS_DA_LOGRANGE(node, btree, tmp));
+		btree = &node->btree[ INT_GET(node->hdr.count, ARCH_CONVERT)-1 ];
+	}
+	memset((char *)btree, 0, sizeof(xfs_da_node_entry_t));
+	xfs_da_log_buf(state->args->trans, drop_blk->bp,
+	    XFS_DA_LOGRANGE(node, btree, sizeof(*btree)));
+	INT_MOD(node->hdr.count, ARCH_CONVERT, -1);
+	xfs_da_log_buf(state->args->trans, drop_blk->bp,
+	    XFS_DA_LOGRANGE(node, &node->hdr, sizeof(node->hdr)));
+
+	/*
+	 * Copy the last hash value from the block to propagate upwards.
+	 */
+	btree--;
+	drop_blk->hashval = INT_GET(btree->hashval, ARCH_CONVERT);
+}
+
+/*
+ * Unbalance the btree elements between two intermediate nodes,
+ * move all Btree elements from one node into another.
+ */
+STATIC void
+xfs_da_node_unbalance(xfs_da_state_t *state, xfs_da_state_blk_t *drop_blk,
+				     xfs_da_state_blk_t *save_blk)
+{
+	xfs_da_intnode_t *drop_node, *save_node;
+	xfs_da_node_entry_t *btree;
+	int tmp;
+	xfs_trans_t *tp;
+
+	drop_node = drop_blk->bp->data;
+	save_node = save_blk->bp->data;
+	ASSERT(INT_GET(drop_node->hdr.info.magic, ARCH_CONVERT) == XFS_DA_NODE_MAGIC);
+	ASSERT(INT_GET(save_node->hdr.info.magic, ARCH_CONVERT) == XFS_DA_NODE_MAGIC);
+	tp = state->args->trans;
+
+	/*
+	 * If the dying block has lower hashvals, then move all the
+	 * elements in the remaining block up to make a hole.
+	 */
+	if ((INT_GET(drop_node->btree[ 0 ].hashval, ARCH_CONVERT) < INT_GET(save_node->btree[ 0 ].hashval, ARCH_CONVERT)) ||
+	    (INT_GET(drop_node->btree[ INT_GET(drop_node->hdr.count, ARCH_CONVERT)-1 ].h