Initial import

1 files changed, 4501 insertions, 0 deletions

diff --git a/fs/ocfs2/dir.c b/fs/ocfs2/dir.c
new file mode 100644
index 000000000..ccd4dcfc3
--- /dev/null
+++ b/fs/ocfs2/dir.c
@@ -0,0 +1,4501 @@
+/* -*- mode: c; c-basic-offset: 8; -*-
+ * vim: noexpandtab sw=8 ts=8 sts=0:
+ *
+ * dir.c
+ *
+ * Creates, reads, walks and deletes directory-nodes
+ *
+ * Copyright (C) 2002, 2004 Oracle.  All rights reserved.
+ *
+ *  Portions of this code from linux/fs/ext3/dir.c
+ *
+ *  Copyright (C) 1992, 1993, 1994, 1995
+ *  Remy Card (card@masi.ibp.fr)
+ *  Laboratoire MASI - Institut Blaise pascal
+ *  Universite Pierre et Marie Curie (Paris VI)
+ *
+ *   from
+ *
+ *   linux/fs/minix/dir.c
+ *
+ *   Copyright (C) 1991, 1992 Linus Torvalds
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public
+ * License as published by the Free Software Foundation; either
+ * version 2 of the License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public
+ * License along with this program; if not, write to the
+ * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
+ * Boston, MA 021110-1307, USA.
+ */
+
+#include <linux/fs.h>
+#include <linux/types.h>
+#include <linux/slab.h>
+#include <linux/highmem.h>
+#include <linux/quotaops.h>
+#include <linux/sort.h>
+
+#include <cluster/masklog.h>
+
+#include "ocfs2.h"
+
+#include "alloc.h"
+#include "blockcheck.h"
+#include "dir.h"
+#include "dlmglue.h"
+#include "extent_map.h"
+#include "file.h"
+#include "inode.h"
+#include "journal.h"
+#include "namei.h"
+#include "suballoc.h"
+#include "super.h"
+#include "sysfile.h"
+#include "uptodate.h"
+#include "ocfs2_trace.h"
+
+#include "buffer_head_io.h"
+
+#define NAMEI_RA_CHUNKS  2
+#define NAMEI_RA_BLOCKS  4
+#define NAMEI_RA_SIZE        (NAMEI_RA_CHUNKS * NAMEI_RA_BLOCKS)
+
+static unsigned char ocfs2_filetype_table[] = {
+	DT_UNKNOWN, DT_REG, DT_DIR, DT_CHR, DT_BLK, DT_FIFO, DT_SOCK, DT_LNK
+};
+
+static int ocfs2_do_extend_dir(struct super_block *sb,
+			       handle_t *handle,
+			       struct inode *dir,
+			       struct buffer_head *parent_fe_bh,
+			       struct ocfs2_alloc_context *data_ac,
+			       struct ocfs2_alloc_context *meta_ac,
+			       struct buffer_head **new_bh);
+static int ocfs2_dir_indexed(struct inode *inode);
+
+/*
+ * These are distinct checks because future versions of the file system will
+ * want to have a trailing dirent structure independent of indexing.
+ */
+static int ocfs2_supports_dir_trailer(struct inode *dir)
+{
+	struct ocfs2_super *osb = OCFS2_SB(dir->i_sb);
+
+	if (OCFS2_I(dir)->ip_dyn_features & OCFS2_INLINE_DATA_FL)
+		return 0;
+
+	return ocfs2_meta_ecc(osb) || ocfs2_dir_indexed(dir);
+}
+
+/*
+ * "new' here refers to the point at which we're creating a new
+ * directory via "mkdir()", but also when we're expanding an inline
+ * directory. In either case, we don't yet have the indexing bit set
+ * on the directory, so the standard checks will fail in when metaecc
+ * is turned off. Only directory-initialization type functions should
+ * use this then. Everything else wants ocfs2_supports_dir_trailer()
+ */
+static int ocfs2_new_dir_wants_trailer(struct inode *dir)
+{
+	struct ocfs2_super *osb = OCFS2_SB(dir->i_sb);
+
+	return ocfs2_meta_ecc(osb) ||
+		ocfs2_supports_indexed_dirs(osb);
+}
+
+static inline unsigned int ocfs2_dir_trailer_blk_off(struct super_block *sb)
+{
+	return sb->s_blocksize - sizeof(struct ocfs2_dir_block_trailer);
+}
+
+#define ocfs2_trailer_from_bh(_bh, _sb) ((struct ocfs2_dir_block_trailer *) ((_bh)->b_data + ocfs2_dir_trailer_blk_off((_sb))))
+
+/* XXX ocfs2_block_dqtrailer() is similar but not quite - can we make
+ * them more consistent? */
+struct ocfs2_dir_block_trailer *ocfs2_dir_trailer_from_size(int blocksize,
+							    void *data)
+{
+	char *p = data;
+
+	p += blocksize - sizeof(struct ocfs2_dir_block_trailer);
+	return (struct ocfs2_dir_block_trailer *)p;
+}
+
+/*
+ * XXX: This is executed once on every dirent. We should consider optimizing
+ * it.
+ */
+static int ocfs2_skip_dir_trailer(struct inode *dir,
+				  struct ocfs2_dir_entry *de,
+				  unsigned long offset,
+				  unsigned long blklen)
+{
+	unsigned long toff = blklen - sizeof(struct ocfs2_dir_block_trailer);
+
+	if (!ocfs2_supports_dir_trailer(dir))
+		return 0;
+
+	if (offset != toff)
+		return 0;
+
+	return 1;
+}
+
+static void ocfs2_init_dir_trailer(struct inode *inode,
+				   struct buffer_head *bh, u16 rec_len)
+{
+	struct ocfs2_dir_block_trailer *trailer;
+
+	trailer = ocfs2_trailer_from_bh(bh, inode->i_sb);
+	strcpy(trailer->db_signature, OCFS2_DIR_TRAILER_SIGNATURE);
+	trailer->db_compat_rec_len =
+			cpu_to_le16(sizeof(struct ocfs2_dir_block_trailer));
+	trailer->db_parent_dinode = cpu_to_le64(OCFS2_I(inode)->ip_blkno);
+	trailer->db_blkno = cpu_to_le64(bh->b_blocknr);
+	trailer->db_free_rec_len = cpu_to_le16(rec_len);
+}
+/*
+ * Link an unindexed block with a dir trailer structure into the index free
+ * list. This function will modify dirdata_bh, but assumes you've already
+ * passed it to the journal.
+ */
+static int ocfs2_dx_dir_link_trailer(struct inode *dir, handle_t *handle,
+				     struct buffer_head *dx_root_bh,
+				     struct buffer_head *dirdata_bh)
+{
+	int ret;
+	struct ocfs2_dx_root_block *dx_root;
+	struct ocfs2_dir_block_trailer *trailer;
+
+	ret = ocfs2_journal_access_dr(handle, INODE_CACHE(dir), dx_root_bh,
+				      OCFS2_JOURNAL_ACCESS_WRITE);
+	if (ret) {
+		mlog_errno(ret);
+		goto out;
+	}
+	trailer = ocfs2_trailer_from_bh(dirdata_bh, dir->i_sb);
+	dx_root = (struct ocfs2_dx_root_block *)dx_root_bh->b_data;
+
+	trailer->db_free_next = dx_root->dr_free_blk;
+	dx_root->dr_free_blk = cpu_to_le64(dirdata_bh->b_blocknr);
+
+	ocfs2_journal_dirty(handle, dx_root_bh);
+
+out:
+	return ret;
+}
+
+static int ocfs2_free_list_at_root(struct ocfs2_dir_lookup_result *res)
+{
+	return res->dl_prev_leaf_bh == NULL;
+}
+
+void ocfs2_free_dir_lookup_result(struct ocfs2_dir_lookup_result *res)
+{
+	brelse(res->dl_dx_root_bh);
+	brelse(res->dl_leaf_bh);
+	brelse(res->dl_dx_leaf_bh);
+	brelse(res->dl_prev_leaf_bh);
+}
+
+static int ocfs2_dir_indexed(struct inode *inode)
+{
+	if (OCFS2_I(inode)->ip_dyn_features & OCFS2_INDEXED_DIR_FL)
+		return 1;
+	return 0;
+}
+
+static inline int ocfs2_dx_root_inline(struct ocfs2_dx_root_block *dx_root)
+{
+	return dx_root->dr_flags & OCFS2_DX_FLAG_INLINE;
+}
+
+/*
+ * Hashing code adapted from ext3
+ */
+#define DELTA 0x9E3779B9
+
+static void TEA_transform(__u32 buf[4], __u32 const in[])
+{
+	__u32	sum = 0;
+	__u32	b0 = buf[0], b1 = buf[1];
+	__u32	a = in[0], b = in[1], c = in[2], d = in[3];
+	int	n = 16;
+
+	do {
+		sum += DELTA;
+		b0 += ((b1 << 4)+a) ^ (b1+sum) ^ ((b1 >> 5)+b);
+		b1 += ((b0 << 4)+c) ^ (b0+sum) ^ ((b0 >> 5)+d);
+	} while (--n);
+
+	buf[0] += b0;
+	buf[1] += b1;
+}
+
+static void str2hashbuf(const char *msg, int len, __u32 *buf, int num)
+{
+	__u32	pad, val;
+	int	i;
+
+	pad = (__u32)len | ((__u32)len << 8);
+	pad |= pad << 16;
+
+	val = pad;
+	if (len > num*4)
+		len = num * 4;
+	for (i = 0; i < len; i++) {
+		if ((i % 4) == 0)
+			val = pad;
+		val = msg[i] + (val << 8);
+		if ((i % 4) == 3) {
+			*buf++ = val;
+			val = pad;
+			num--;
+		}
+	}
+	if (--num >= 0)
+		*buf++ = val;
+	while (--num >= 0)
+		*buf++ = pad;
+}
+
+static void ocfs2_dx_dir_name_hash(struct inode *dir, const char *name, int len,
+				   struct ocfs2_dx_hinfo *hinfo)
+{
+	struct ocfs2_super *osb = OCFS2_SB(dir->i_sb);
+	const char	*p;
+	__u32		in[8], buf[4];
+
+	/*
+	 * XXX: Is this really necessary, if the index is never looked
+	 * at by readdir? Is a hash value of '0' a bad idea?
+	 */
+	if ((len == 1 && !strncmp(".", name, 1)) ||
+	    (len == 2 && !strncmp("..", name, 2))) {
+		buf[0] = buf[1] = 0;
+		goto out;
+	}
+
+#ifdef OCFS2_DEBUG_DX_DIRS
+	/*
+	 * This makes it very easy to debug indexing problems. We
+	 * should never allow this to be selected without hand editing
+	 * this file though.
+	 */
+	buf[0] = buf[1] = len;
+	goto out;
+#endif
+
+	memcpy(buf, osb->osb_dx_seed, sizeof(buf));
+
+	p = name;
+	while (len > 0) {
+		str2hashbuf(p, len, in, 4);
+		TEA_transform(buf, in);
+		len -= 16;
+		p += 16;
+	}
+
+out:
+	hinfo->major_hash = buf[0];
+	hinfo->minor_hash = buf[1];
+}
+
+/*
+ * bh passed here can be an inode block or a dir data block, depending
+ * on the inode inline data flag.
+ */
+static int ocfs2_check_dir_entry(struct inode * dir,
+				 struct ocfs2_dir_entry * de,
+				 struct buffer_head * bh,
+				 unsigned long offset)
+{
+	const char *error_msg = NULL;
+	const int rlen = le16_to_cpu(de->rec_len);
+
+	if (unlikely(rlen < OCFS2_DIR_REC_LEN(1)))
+		error_msg = "rec_len is smaller than minimal";
+	else if (unlikely(rlen % 4 != 0))
+		error_msg = "rec_len % 4 != 0";
+	else if (unlikely(rlen < OCFS2_DIR_REC_LEN(de->name_len)))
+		error_msg = "rec_len is too small for name_len";
+	else if (unlikely(
+		 ((char *) de - bh->b_data) + rlen > dir->i_sb->s_blocksize))
+		error_msg = "directory entry across blocks";
+
+	if (unlikely(error_msg != NULL))
+		mlog(ML_ERROR, "bad entry in directory #%llu: %s - "
+		     "offset=%lu, inode=%llu, rec_len=%d, name_len=%d\n",
+		     (unsigned long long)OCFS2_I(dir)->ip_blkno, error_msg,
+		     offset, (unsigned long long)le64_to_cpu(de->inode), rlen,
+		     de->name_len);
+
+	return error_msg == NULL ? 1 : 0;
+}
+
+static inline int ocfs2_match(int len,
+			      const char * const name,
+			      struct ocfs2_dir_entry *de)
+{
+	if (len != de->name_len)
+		return 0;
+	if (!de->inode)
+		return 0;
+	return !memcmp(name, de->name, len);
+}
+
+/*
+ * Returns 0 if not found, -1 on failure, and 1 on success
+ */
+static inline int ocfs2_search_dirblock(struct buffer_head *bh,
+					struct inode *dir,
+					const char *name, int namelen,
+					unsigned long offset,
+					char *first_de,
+					unsigned int bytes,
+					struct ocfs2_dir_entry **res_dir)
+{
+	struct ocfs2_dir_entry *de;
+	char *dlimit, *de_buf;
+	int de_len;
+	int ret = 0;
+
+	de_buf = first_de;
+	dlimit = de_buf + bytes;
+
+	while (de_buf < dlimit) {
+		/* this code is executed quadratically often */
+		/* do minimal checking `by hand' */
+
+		de = (struct ocfs2_dir_entry *) de_buf;
+
+		if (de_buf + namelen <= dlimit &&
+		    ocfs2_match(namelen, name, de)) {
+			/* found a match - just to be sure, do a full check */
+			if (!ocfs2_check_dir_entry(dir, de, bh, offset)) {
+				ret = -1;
+				goto bail;
+			}
+			*res_dir = de;
+			ret = 1;
+			goto bail;
+		}
+
+		/* prevent looping on a bad block */
+		de_len = le16_to_cpu(de->rec_len);
+		if (de_len <= 0) {
+			ret = -1;
+			goto bail;
+		}
+
+		de_buf += de_len;
+		offset += de_len;
+	}
+
+bail:
+	trace_ocfs2_search_dirblock(ret);
+	return ret;
+}
+
+static struct buffer_head *ocfs2_find_entry_id(const char *name,
+					       int namelen,
+					       struct inode *dir,
+					       struct ocfs2_dir_entry **res_dir)
+{
+	int ret, found;
+	struct buffer_head *di_bh = NULL;
+	struct ocfs2_dinode *di;
+	struct ocfs2_inline_data *data;
+
+	ret = ocfs2_read_inode_block(dir, &di_bh);
+	if (ret) {
+		mlog_errno(ret);
+		goto out;
+	}
+
+	di = (struct ocfs2_dinode *)di_bh->b_data;
+	data = &di->id2.i_data;
+
+	found = ocfs2_search_dirblock(di_bh, dir, name, namelen, 0,
+				      data->id_data, i_size_read(dir), res_dir);
+	if (found == 1)
+		return di_bh;
+
+	brelse(di_bh);
+out:
+	return NULL;
+}
+
+static int ocfs2_validate_dir_block(struct super_block *sb,
+				    struct buffer_head *bh)
+{
+	int rc;
+	struct ocfs2_dir_block_trailer *trailer =
+		ocfs2_trailer_from_bh(bh, sb);
+
+
+	/*
+	 * We don't validate dirents here, that's handled
+	 * in-place when the code walks them.
+	 */
+	trace_ocfs2_validate_dir_block((unsigned long long)bh->b_blocknr);
+
+	BUG_ON(!buffer_uptodate(bh));
+
+	/*
+	 * If the ecc fails, we return the error but otherwise
+	 * leave the filesystem running.  We know any error is
+	 * local to this block.
+	 *
+	 * Note that we are safe to call this even if the directory
+	 * doesn't have a trailer.  Filesystems without metaecc will do
+	 * nothing, and filesystems with it will have one.
+	 */
+	rc = ocfs2_validate_meta_ecc(sb, bh->b_data, &trailer->db_check);
+	if (rc)
+		mlog(ML_ERROR, "Checksum failed for dinode %llu\n",
+		     (unsigned long long)bh->b_blocknr);
+
+	return rc;
+}
+
+/*
+ * Validate a directory trailer.
+ *
+ * We check the trailer here rather than in ocfs2_validate_dir_block()
+ * because that function doesn't have the inode to test.
+ */
+static int ocfs2_check_dir_trailer(struct inode *dir, struct buffer_head *bh)
+{
+	int rc = 0;
+	struct ocfs2_dir_block_trailer *trailer;
+
+	trailer = ocfs2_trailer_from_bh(bh, dir->i_sb);
+	if (!OCFS2_IS_VALID_DIR_TRAILER(trailer)) {
+		rc = -EINVAL;
+		ocfs2_error(dir->i_sb,
+			    "Invalid dirblock #%llu: "
+			    "signature = %.*s\n",
+			    (unsigned long long)bh->b_blocknr, 7,
+			    trailer->db_signature);
+		goto out;
+	}
+	if (le64_to_cpu(trailer->db_blkno) != bh->b_blocknr) {
+		rc = -EINVAL;
+		ocfs2_error(dir->i_sb,
+			    "Directory block #%llu has an invalid "
+			    "db_blkno of %llu",
+			    (unsigned long long)bh->b_blocknr,
+			    (unsigned long long)le64_to_cpu(trailer->db_blkno));
+		goto out;
+	}
+	if (le64_to_cpu(trailer->db_parent_dinode) !=
+	    OCFS2_I(dir)->ip_blkno) {
+		rc = -EINVAL;
+		ocfs2_error(dir->i_sb,
+			    "Directory block #%llu on dinode "
+			    "#%llu has an invalid parent_dinode "
+			    "of %llu",
+			    (unsigned long long)bh->b_blocknr,
+			    (unsigned long long)OCFS2_I(dir)->ip_blkno,
+			    (unsigned long long)le64_to_cpu(trailer->db_blkno));
+		goto out;
+	}
+out:
+	return rc;
+}
+
+/*
+ * This function forces all errors to -EIO for consistency with its
+ * predecessor, ocfs2_bread().  We haven't audited what returning the
+ * real error codes would do to callers.  We log the real codes with
+ * mlog_errno() before we squash them.
+ */
+static int ocfs2_read_dir_block(struct inode *inode, u64 v_block,
+				struct buffer_head **bh, int flags)
+{
+	int rc = 0;
+	struct buffer_head *tmp = *bh;
+
+	rc = ocfs2_read_virt_blocks(inode, v_block, 1, &tmp, flags,
+				    ocfs2_validate_dir_block);
+	if (rc) {
+		mlog_errno(rc);
+		goto out;
+	}
+
+	if (!(flags & OCFS2_BH_READAHEAD) &&
+	    ocfs2_supports_dir_trailer(inode)) {
+		rc = ocfs2_check_dir_trailer(inode, tmp);
+		if (rc) {
+			if (!*bh)
+				brelse(tmp);
+			mlog_errno(rc);
+			goto out;
+		}
+	}
+
+	/* If ocfs2_read_virt_blocks() got us a new bh, pass it up. */
+	if (!*bh)
+		*bh = tmp;
+
+out:
+	return rc ? -EIO : 0;
+}
+
+/*
+ * Read the block at 'phys' which belongs to this directory
+ * inode. This function does no virtual->physical block translation -
+ * what's passed in is assumed to be a valid directory block.
+ */
+static int ocfs2_read_dir_block_direct(struct inode *dir, u64 phys,
+				       struct buffer_head **bh)
+{
+	int ret;
+	struct buffer_head *tmp = *bh;
+
+	ret = ocfs2_read_block(INODE_CACHE(dir), phys, &tmp,
+			       ocfs2_validate_dir_block);
+	if (ret) {
+		mlog_errno(ret);
+		goto out;
+	}
+
+	if (ocfs2_supports_dir_trailer(dir)) {
+		ret = ocfs2_check_dir_trailer(dir, tmp);
+		if (ret) {
+			if (!*bh)
+				brelse(tmp);
+			mlog_errno(ret);
+			goto out;
+		}
+	}
+
+	if (!ret && !*bh)
+		*bh = tmp;
+out:
+	return ret;
+}
+
+static int ocfs2_validate_dx_root(struct super_block *sb,
+				  struct buffer_head *bh)
+{
+	int ret;
+	struct ocfs2_dx_root_block *dx_root;
+
+	BUG_ON(!buffer_uptodate(bh));
+
+	dx_root = (struct ocfs2_dx_root_block *) bh->b_data;
+
+	ret = ocfs2_validate_meta_ecc(sb, bh->b_data, &dx_root->dr_check);
+	if (ret) {
+		mlog(ML_ERROR,
+		     "Checksum failed for dir index root block %llu\n",
+		     (unsigned long long)bh->b_blocknr);
+		return ret;
+	}
+
+	if (!OCFS2_IS_VALID_DX_ROOT(dx_root)) {
+		ocfs2_error(sb,
+			    "Dir Index Root # %llu has bad signature %.*s",
+			    (unsigned long long)le64_to_cpu(dx_root->dr_blkno),
+			    7, dx_root->dr_signature);
+		return -EINVAL;
+	}
+
+	return 0;
+}
+
+static int ocfs2_read_dx_root(struct inode *dir, struct ocfs2_dinode *di,
+			      struct buffer_head **dx_root_bh)
+{
+	int ret;
+	u64 blkno = le64_to_cpu(di->i_dx_root);
+	struct buffer_head *tmp = *dx_root_bh;
+
+	ret = ocfs2_read_block(INODE_CACHE(dir), blkno, &tmp,
+			       ocfs2_validate_dx_root);
+
+	/* If ocfs2_read_block() got us a new bh, pass it up. */
+	if (!ret && !*dx_root_bh)
+		*dx_root_bh = tmp;
+
+	return ret;
+}
+
+static int ocfs2_validate_dx_leaf(struct super_block *sb,
+				  struct buffer_head *bh)
+{
+	int ret;
+	struct ocfs2_dx_leaf *dx_leaf = (struct ocfs2_dx_leaf *)bh->b_data;
+
+	BUG_ON(!buffer_uptodate(bh));
+
+	ret = ocfs2_validate_meta_ecc(sb, bh->b_data, &dx_leaf->dl_check);
+	if (ret) {
+		mlog(ML_ERROR,
+		     "Checksum failed for dir index leaf block %llu\n",
+		     (unsigned long long)bh->b_blocknr);
+		return ret;
+	}
+
+	if (!OCFS2_IS_VALID_DX_LEAF(dx_leaf)) {
+		ocfs2_error(sb, "Dir Index Leaf has bad signature %.*s",
+			    7, dx_leaf->dl_signature);
+		return -EROFS;
+	}
+
+	return 0;
+}
+
+static int ocfs2_read_dx_leaf(struct inode *dir, u64 blkno,
+			      struct buffer_head **dx_leaf_bh)
+{
+	int ret;
+	struct buffer_head *tmp = *dx_leaf_bh;
+
+	ret = ocfs2_read_block(INODE_CACHE(dir), blkno, &tmp,
+			       ocfs2_validate_dx_leaf);
+
+	/* If ocfs2_read_block() got us a new bh, pass it up. */
+	if (!ret && !*dx_leaf_bh)
+		*dx_leaf_bh = tmp;
+
+	return ret;
+}
+
+/*
+ * Read a series of dx_leaf blocks. This expects all buffer_head
+ * pointers to be NULL on function entry.
+ */
+static int ocfs2_read_dx_leaves(struct inode *dir, u64 start, int num,
+				struct buffer_head **dx_leaf_bhs)
+{
+	int ret;
+
+	ret = ocfs2_read_blocks(INODE_CACHE(dir), start, num, dx_leaf_bhs, 0,
+				ocfs2_validate_dx_leaf);
+	if (ret)
+		mlog_errno(ret);
+
+	return ret;
+}
+
+static struct buffer_head *ocfs2_find_entry_el(const char *name, int namelen,
+					       struct inode *dir,
+					       struct ocfs2_dir_entry **res_dir)
+{
+	struct super_block *sb;
+	struct buffer_head *bh_use[NAMEI_RA_SIZE];
+	struct buffer_head *bh, *ret = NULL;
+	unsigned long start, block, b;
+	int ra_max = 0;		/* Number of bh's in the readahead
+				   buffer, bh_use[] */
+	int ra_ptr = 0;		/* Current index into readahead
+				   buffer */
+	int num = 0;
+	int nblocks, i, err;
+
+	sb = dir->i_sb;
+
+	nblocks = i_size_read(dir) >> sb->s_blocksize_bits;
+	start = OCFS2_I(dir)->ip_dir_start_lookup;
+	if (start >= nblocks)
+		start = 0;
+	block = start;
+
+restart:
+	do {
+		/*
+		 * We deal with the read-ahead logic here.
+		 */
+		if (ra_ptr >= ra_max) {
+			/* Refill the readahead buffer */
+			ra_ptr = 0;
+			b = block;
+			for (ra_max = 0; ra_max < NAMEI_RA_SIZE; ra_max++) {
+				/*
+				 * Terminate if we reach the end of the
+				 * directory and must wrap, or if our
+				 * search has finished at this block.
+				 */
+				if (b >= nblocks || (num && block == start)) {
+					bh_use[ra_max] = NULL;
+					break;
+				}
+				num++;
+
+				bh = NULL;
+				err = ocfs2_read_dir_block(dir, b++, &bh,
+							   OCFS2_BH_READAHEAD);
+				bh_use[ra_max] = bh;
+			}
+		}
+		if ((bh = bh_use[ra_ptr++]) == NULL)
+			goto next;
+		if (ocfs2_read_dir_block(dir, block, &bh, 0)) {
+			/* read error, skip block & hope for the best.
+			 * ocfs2_read_dir_block() has released the bh. */
+			mlog(ML_ERROR, "reading directory %llu, "
+				    "offset %lu\n",
+				    (unsigned long long)OCFS2_I(dir)->ip_blkno,
+				    block);
+			goto next;
+		}
+		i = ocfs2_search_dirblock(bh, dir, name, namelen,
+					  block << sb->s_blocksize_bits,
+					  bh->b_data, sb->s_blocksize,
+					  res_dir);
+		if (i == 1) {
+			OCFS2_I(dir)->ip_dir_start_lookup = block;
+			ret = bh;
+			goto cleanup_and_exit;
+		} else {
+			brelse(bh);
+			if (i < 0)
+				goto cleanup_and_exit;
+		}
+	next:
+		if (++block >= nblocks)
+			block = 0;
+	} while (block != start);
+
+	/*
+	 * If the directory has grown while we were searching, then
+	 * search the last part of the directory before giving up.
+	 */
+	block = nblocks;
+	nblocks = i_size_read(dir) >> sb->s_blocksize_bits;
+	if (block < nblocks) {
+		start = 0;
+		goto restart;
+	}
+
+cleanup_and_exit:
+	/* Clean up the read-ahead blocks */
+	for (; ra_ptr < ra_max; ra_ptr++)
+		brelse(bh_use[ra_ptr]);
+
+	trace_ocfs2_find_entry_el(ret);
+	return ret;
+}
+
+static int ocfs2_dx_dir_lookup_rec(struct inode *inode,
+				   struct ocfs2_extent_list *el,
+				   u32 major_hash,
+				   u32 *ret_cpos,
+				   u64 *ret_phys_blkno,
+				   unsigned int *ret_clen)
+{
+	int ret = 0, i, found;
+	struct buffer_head *eb_bh = NULL;
+	struct ocfs2_extent_block *eb;
+	struct ocfs2_extent_rec *rec = NULL;
+
+	if (el->l_tree_depth) {
+		ret = ocfs2_find_leaf(INODE_CACHE(inode), el, major_hash,
+				      &eb_bh);
+		if (ret) {
+			mlog_errno(ret);
+			goto out;
+		}
+
+		eb = (struct ocfs2_extent_block *) eb_bh->b_data;
+		el = &eb->h_list;
+
+		if (el->l_tree_depth) {
+			ocfs2_error(inode->i_sb,
+				    "Inode %lu has non zero tree depth in "
+				    "btree tree block %llu\n", inode->i_ino,
+				    (unsigned long long)eb_bh->b_blocknr);
+			ret = -EROFS;
+			goto out;
+		}
+	}
+
+	found = 0;
+	for (i = le16_to_cpu(el->l_next_free_rec) - 1; i >= 0; i--) {
+		rec = &el->l_recs[i];
+
+		if (le32_to_cpu(rec->e_cpos) <= major_hash) {
+			found = 1;
+			break;
+		}
+	}
+
+	if (!found) {
+		ocfs2_error(inode->i_sb, "Inode %lu has bad extent "
+			    "record (%u, %u, 0) in btree", inode->i_ino,
+			    le32_to_cpu(rec->e_cpos),
+			    ocfs2_rec_clusters(el, rec));
+		ret = -EROFS;
+		goto out;
+	}
+
+	if (ret_phys_blkno)
+		*ret_phys_blkno = le64_to_cpu(rec->e_blkno);
+	if (ret_cpos)
+		*ret_cpos = le32_to_cpu(rec->e_cpos);
+	if (ret_clen)
+		*ret_clen = le16_to_cpu(rec->e_leaf_clusters);
+
+out:
+	brelse(eb_bh);
+	return ret;
+}
+
+/*
+ * Returns the block index, from the start of the cluster which this
+ * hash belongs too.
+ */
+static inline unsigned int __ocfs2_dx_dir_hash_idx(struct ocfs2_super *osb,
+						   u32 minor_hash)
+{
+	return minor_hash & osb->osb_dx_mask;
+}
+
+static inline unsigned int ocfs2_dx_dir_hash_idx(struct ocfs2_super *osb,
+					  struct ocfs2_dx_hinfo *hinfo)
+{
+	return __ocfs2_dx_dir_hash_idx(osb, hinfo->minor_hash);
+}
+
+static int ocfs2_dx_dir_lookup(struct inode *inode,
+			       struct ocfs2_extent_list *el,
+			       struct ocfs2_dx_hinfo *hinfo,
+			       u32 *ret_cpos,
+			       u64 *ret_phys_blkno)
+{
+	int ret = 0;
+	unsigned int cend, uninitialized_var(clen);
+	u32 uninitialized_var(cpos);
+	u64 uninitialized_var(blkno);
+	u32 name_hash = hinfo->major_hash;
+
+	ret = ocfs2_dx_dir_lookup_rec(inode, el, name_hash, &cpos, &blkno,
+				      &clen);
+	if (ret) {
+		mlog_errno(ret);
+		goto out;
+	}
+
+	cend = cpos + clen;
+	if (name_hash >= cend) {
+		/* We want the last cluster */
+		blkno += ocfs2_clusters_to_blocks(inode->i_sb, clen - 1);
+		cpos += clen - 1;
+	} else {
+		blkno += ocfs2_clusters_to_blocks(inode->i_sb,
+						  name_hash - cpos);
+		cpos = name_hash;
+	}
+
+	/*
+	 * We now have the cluster which should hold our entry. To
+	 * find the exact block from the start of the cluster to
+	 * search, we take the lower bits of the hash.
+	 */
+	blkno += ocfs2_dx_dir_hash_idx(OCFS2_SB(inode->i_sb), hinfo);
+
+	if (ret_phys_blkno)
+		*ret_phys_blkno = blkno;
+	if (ret_cpos)
+		*ret_cpos = cpos;
+
+out:
+
+	return ret;
+}
+
+static int ocfs2_dx_dir_search(const char *name, int namelen,
+			       struct inode *dir,
+			       struct ocfs2_dx_root_block *dx_root,
+			       struct ocfs2_dir_lookup_result *res)
+{
+	int ret, i, found;
+	u64 uninitialized_var(phys);
+	struct buffer_head *dx_leaf_bh = NULL;
+	struct ocfs2_dx_leaf *dx_leaf;
+	struct ocfs2_dx_entry *dx_entry = NULL;
+	struct buffer_head *dir_ent_bh = NULL;
+	struct ocfs2_dir_entry *dir_ent = NULL;
+	struct ocfs2_dx_hinfo *hinfo = &res->dl_hinfo;
+	struct ocfs2_extent_list *dr_el;
+	struct ocfs2_dx_entry_list *entry_list;
+
+	ocfs2_dx_dir_name_hash(dir, name, namelen, &res->dl_hinfo);
+
+	if (ocfs2_dx_root_inline(dx_root)) {
+		entry_list = &dx_root->dr_entries;
+		goto search;
+	}
+
+	dr_el = &dx_root->dr_list;
+
+	ret = ocfs2_dx_dir_lookup(dir, dr_el, hinfo, NULL, &phys);
+	if (ret) {
+		mlog_errno(ret);
+		goto out;
+	}
+
+	trace_ocfs2_dx_dir_search((unsigned long long)OCFS2_I(dir)->ip_blkno,
+				  namelen, name, hinfo->major_hash,
+				  hinfo->minor_hash, (unsigned long long)phys);
+
+	ret = ocfs2_read_dx_leaf(dir, phys, &dx_leaf_bh);
+	if (ret) {
+		mlog_errno(ret);
+		goto out;
+	}
+
+	dx_leaf = (struct ocfs2_dx_leaf *) dx_leaf_bh->b_data;
+
+	trace_ocfs2_dx_dir_search_leaf_info(
+			le16_to_cpu(dx_leaf->dl_list.de_num_used),
+			le16_to_cpu(dx_leaf->dl_list.de_count));
+
+	entry_list = &dx_leaf->dl_list;
+
+search:
+	/*
+	 * Empty leaf is legal, so no need to check for that.
+	 */
+	found = 0;
+	for (i = 0; i < le16_to_cpu(entry_list->de_num_used); i++) {
+		dx_entry = &entry_list->de_entries[i];
+
+		if (hinfo->major_hash != le32_to_cpu(dx_entry->dx_major_hash)
+		    || hinfo->minor_hash != le32_to_cpu(dx_entry->dx_minor_hash))
+			continue;
+
+		/*
+		 * Search unindexed leaf block now. We're not
+		 * guaranteed to find anything.
+		 */
+		ret = ocfs2_read_dir_block_direct(dir,
+					  le64_to_cpu(dx_entry->dx_dirent_blk),
+					  &dir_ent_bh);
+		if (ret) {
+			mlog_errno(ret);
+			goto out;
+		}
+
+		/*
+		 * XXX: We should check the unindexed block here,
+		 * before using it.
+		 */
+
+		found = ocfs2_search_dirblock(dir_ent_bh, dir, name, namelen,
+					      0, dir_ent_bh->b_data,
+					      dir->i_sb->s_blocksize, &dir_ent);
+		if (found == 1)
+			break;
+
+		if (found == -1) {
+			/* This means we found a bad directory entry. */
+			ret = -EIO;
+			mlog_errno(ret);
+			goto out;
+		}
+
+		brelse(dir_ent_bh);
+		dir_ent_bh = NULL;
+	}
+
+	if (found <= 0) {
+		ret = -ENOENT;
+		goto out;
+	}
+
+	res->dl_leaf_bh = dir_ent_bh;
+	res->dl_entry = dir_ent;
+	res->dl_dx_leaf_bh = dx_leaf_bh;
+	res->dl_dx_entry = dx_entry;
+
+	ret = 0;
+out:
+	if (ret) {
+		brelse(dx_leaf_bh);
+		brelse(dir_ent_bh);
+	}
+	return ret;
+}
+
+static int ocfs2_find_entry_dx(const char *name, int namelen,
+			       struct inode *dir,
+			       struct ocfs2_dir_lookup_result *lookup)
+{
+	int ret;
+	struct buffer_head *di_bh = NULL;
+	struct ocfs2_dinode *di;
+	struct buffer_head *dx_root_bh = NULL;
+	struct ocfs2_dx_root_block *dx_root;
+
+	ret = ocfs2_read_inode_block(dir, &di_bh);
+	if (ret) {
+		mlog_errno(ret);
+		goto out;
+	}
+
+	di = (struct ocfs2_dinode *)di_bh->b_data;
+
+	ret = ocfs2_read_dx_root(dir, di, &dx_root_bh);
+	if (ret) {
+		mlog_errno(ret);
+		goto out;
+	}
+	dx_root = (struct ocfs2_dx_root_block *) dx_root_bh->b_data;
+
+	ret = ocfs2_dx_dir_search(name, namelen, dir, dx_root, lookup);
+	if (ret) {
+		if (ret != -ENOENT)
+			mlog_errno(ret);
+		goto out;
+	}
+
+	lookup->dl_dx_root_bh = dx_root_bh;
+	dx_root_bh = NULL;
+out:
+	brelse(di_bh);
+	brelse(dx_root_bh);
+	return ret;
+}
+
+/*
+ * Try to find an entry of the provided name within 'dir'.
+ *
+ * If nothing was found, -ENOENT is returned. Otherwise, zero is
+ * returned and the struct 'res' will contain information useful to
+ * other directory manipulation functions.
+ *
+ * Caller can NOT assume anything about the contents of the
+ * buffer_heads - they are passed back only so that it can be passed
+ * into any one of the manipulation functions (add entry, delete
+ * entry, etc). As an example, bh in the extent directory case is a
+ * data block, in the inline-data case it actually points to an inode,
+ * in the indexed directory case, multiple buffers are involved.
+ */
+int ocfs2_find_entry(const char *name, int namelen,
+		     struct inode *dir, struct ocfs2_dir_lookup_result *lookup)
+{
+	struct buffer_head *bh;
+	struct ocfs2_dir_entry *res_dir = NULL;
+
+	if (ocfs2_dir_indexed(dir))
+		return ocfs2_find_entry_dx(name, namelen, dir, lookup);
+
+	/*
+	 * The unindexed dir code only uses part of the lookup
+	 * structure, so there's no reason to push it down further
+	 * than this.
+	 */
+	if (OCFS2_I(dir)->ip_dyn_features & OCFS2_INLINE_DATA_FL)
+		bh = ocfs2_find_entry_id(name, namelen, dir, &res_dir);
+	else
+		bh = ocfs2_find_entry_el(name, namelen, dir, &res_dir);
+
+	if (bh == NULL)
+		return -ENOENT;
+
+	lookup->dl_leaf_bh = bh;
+	lookup->dl_entry = res_dir;
+	return 0;
+}
+
+/*
+ * Update inode number and type of a previously found directory entry.
+ */
+int ocfs2_update_entry(struct inode *dir, handle_t *handle,
+		       struct ocfs2_dir_lookup_result *res,
+		       struct inode *new_entry_inode)
+{
+	int ret;
+	ocfs2_journal_access_func access = ocfs2_journal_access_db;
+	struct ocfs2_dir_entry *de = res->dl_entry;
+	struct buffer_head *de_bh = res->dl_leaf_bh;
+
+	/*
+	 * The same code works fine for both inline-data and extent
+	 * based directories, so no need to split this up.  The only
+	 * difference is the journal_access function.
+	 */
+
+	if (OCFS2_I(dir)->ip_dyn_features & OCFS2_INLINE_DATA_FL)
+		access = ocfs2_journal_access_di;
+
+	ret = access(handle, INODE_CACHE(dir), de_bh,
+		     OCFS2_JOURNAL_ACCESS_WRITE);
+	if (ret) {
+		mlog_errno(ret);
+		goto out;
+	}
+
+	de->inode = cpu_to_le64(OCFS2_I(new_entry_inode)->ip_blkno);
+	ocfs2_set_de_type(de, new_entry_inode->i_mode);
+
+	ocfs2_journal_dirty(handle, de_bh);
+
+out:
+	return ret;
+}
+
+/*
+ * __ocfs2_delete_entry deletes a directory entry by merging it with the
+ * previous entry
+ */
+static int __ocfs2_delete_entry(handle_t *handle, struct inode *dir,
+				struct ocfs2_dir_entry *de_del,
+				struct buffer_head *bh, char *first_de,
+				unsigned int bytes)
+{
+	struct ocfs2_dir_entry *de, *pde;
+	int i, status = -ENOENT;
+	ocfs2_journal_access_func access = ocfs2_journal_access_db;
+
+	if (OCFS2_I(dir)->ip_dyn_features & OCFS2_INLINE_DATA_FL)
+		access = ocfs2_journal_access_di;
+
+	i = 0;
+	pde = NULL;
+	de = (struct ocfs2_dir_entry *) first_de;
+	while (i < bytes) {
+		if (!ocfs2_check_dir_entry(dir, de, bh, i)) {
+			status = -EIO;
+			mlog_errno(status);
+			goto bail;
+		}
+		if (de == de_del)  {
+			status = access(handle, INODE_CACHE(dir), bh,
+					OCFS2_JOURNAL_ACCESS_WRITE);
+			if (status < 0) {
+				status = -EIO;
+				mlog_errno(status);
+				goto bail;
+			}
+			if (pde)
+				le16_add_cpu(&pde->rec_len,
+						le16_to_cpu(de->rec_len));
+			de->inode = 0;
+			dir->i_version++;
+			ocfs2_journal_dirty(handle, bh);
+			goto bail;
+		}
+		i += le16_to_cpu(de->rec_len);
+		pde = de;
+		de = (struct ocfs2_dir_entry *)((char *)de + le16_to_cpu(de->rec_len));
+	}
+bail:
+	return status;
+}
+
+static unsigned int ocfs2_figure_dirent_hole(struct ocfs2_dir_entry *de)
+{
+	unsigned int hole;
+
+	if (le64_to_cpu(de->inode) == 0)
+		hole = le16_to_cpu(de->rec_len);
+	else
+		hole = le16_to_cpu(de->rec_len) -
+			OCFS2_DIR_REC_LEN(de->name_len);
+
+	return hole;
+}
+
+static int ocfs2_find_max_rec_len(struct super_block *sb,
+				  struct buffer_head *dirblock_bh)
+{
+	int size, this_hole, largest_hole = 0;
+	char *trailer, *de_buf, *limit, *start = dirblock_bh->b_data;
+	struct ocfs2_dir_entry *de;
+
+	trailer = (char *)ocfs2_trailer_from_bh(dirblock_bh, sb);
+	size = ocfs2_dir_trailer_blk_off(sb);
+	limit = start + size;
+	de_buf = start;
+	de = (struct ocfs2_dir_entry *)de_buf;
+	do {
+		if (de_buf != trailer) {
+			this_hole = ocfs2_figure_dirent_hole(de);
+			if (this_hole > largest_hole)
+				largest_hole = this_hole;
+		}
+
+		de_buf += le16_to_cpu(de->rec_len);
+		de = (struct ocfs2_dir_entry *)de_buf;
+	} while (de_buf < limit);
+
+	if (largest_hole >= OCFS2_DIR_MIN_REC_LEN)
+		return largest_hole;
+	return 0;
+}
+
+static void ocfs2_dx_list_remove_entry(struct ocfs2_dx_entry_list *entry_list,
+				       int index)
+{
+	int num_used = le16_to_cpu(entry_list->de_num_used);
+
+	if (num_used == 1 || index == (num_used - 1))
+		goto clear;
+
+	memmove(&entry_list->de_entries[index],
+		&entry_list->de_entries[index + 1],
+		(num_used - index - 1)*sizeof(struct ocfs2_dx_entry));
+clear:
+	num_used--;
+	memset(&entry_list->de_entries[num_used], 0,
+	       sizeof(struct ocfs2_dx_entry));
+	entry_list->de_num_used = cpu_to_le16(num_used);
+}
+
+static int ocfs2_delete_entry_dx(handle_t *handle, struct inode *dir,
+				 struct ocfs2_dir_lookup_result *lookup)
+{
+	int ret, index, max_rec_len, add_to_free_list = 0;
+	struct buffer_head *dx_root_bh = lookup->dl_dx_root_bh;
+	struct buffer_head *leaf_bh = lookup->dl_leaf_bh;
+	struct ocfs2_dx_leaf *dx_leaf;
+	struct ocfs2_dx_entry *dx_entry = lookup->dl_dx_entry;
+	struct ocfs2_dir_block_trailer *trailer;
+	struct ocfs2_dx_root_block *dx_root;
+	struct ocfs2_dx_entry_list *entry_list;
+
+	/*
+	 * This function gets a bit messy because we might have to
+	 * modify the root block, regardless of whether the indexed
+	 * entries are stored inline.
+	 */
+
+	/*
+	 * *Only* set 'entry_list' here, based on where we're looking
+	 * for the indexed entries. Later, we might still want to
+	 * journal both blocks, based on free list state.
+	 */
+	dx_root = (struct ocfs2_dx_root_block *)dx_root_bh->b_data;
+	if (ocfs2_dx_root_inline(dx_root)) {
+		entry_list = &dx_root->dr_entries;
+	} else {
+		dx_leaf = (struct ocfs2_dx_leaf *) lookup->dl_dx_leaf_bh->b_data;
+		entry_list = &dx_leaf->dl_list;
+	}
+
+	/* Neither of these are a disk corruption - that should have
+	 * been caught by lookup, before we got here. */
+	BUG_ON(le16_to_cpu(entry_list->de_count) <= 0);
+	BUG_ON(le16_to_cpu(entry_list->de_num_used) <= 0);
+
+	index = (char *)dx_entry - (char *)entry_list->de_entries;
+	index /= sizeof(*dx_entry);
+
+	if (index >= le16_to_cpu(entry_list->de_num_used)) {
+		mlog(ML_ERROR, "Dir %llu: Bad dx_entry ptr idx %d, (%p, %p)\n",
+		     (unsigned long long)OCFS2_I(dir)->ip_blkno, index,
+		     entry_list, dx_entry);
+		return -EIO;
+	}
+
+	/*
+	 * We know that removal of this dirent will leave enough room
+	 * for a new one, so add this block to the free list if it
+	 * isn't already there.
+	 */
+	trailer = ocfs2_trailer_from_bh(leaf_bh, dir->i_sb);
+	if (trailer->db_free_rec_len == 0)
+		add_to_free_list = 1;
+
+	/*
+	 * Add the block holding our index into the journal before
+	 * removing the unindexed entry. If we get an error return
+	 * from __ocfs2_delete_entry(), then it hasn't removed the
+	 * entry yet. Likewise, successful return means we *must*
+	 * remove the indexed entry.
+	 *
+	 * We're also careful to journal the root tree block here as
+	 * the entry count needs to be updated. Also, we might be
+	 * adding to the start of the free list.
+	 */
+	ret = ocfs2_journal_access_dr(handle, INODE_CACHE(dir), dx_root_bh,
+				      OCFS2_JOURNAL_ACCESS_WRITE);
+	if (ret) {
+		mlog_errno(ret);
+		goto out;
+	}
+
+	if (!ocfs2_dx_root_inline(dx_root)) {
+		ret = ocfs2_journal_access_dl(handle, INODE_CACHE(dir),
+					      lookup->dl_dx_leaf_bh,
+					      OCFS2_JOURNAL_ACCESS_WRITE);
+		if (ret) {
+			mlog_errno(ret);
+			goto out;
+		}
+	}
+
+	trace_ocfs2_delete_entry_dx((unsigned long long)OCFS2_I(dir)->ip_blkno,
+				    index);
+
+	ret = __ocfs2_delete_entry(handle, dir, lookup->dl_entry,
+				   leaf_bh, leaf_bh->b_data, leaf_bh->b_size);
+	if (ret) {
+		mlog_errno(ret);
+		goto out;
+	}
+
+	max_rec_len = ocfs2_find_max_rec_len(dir->i_sb, leaf_bh);
+	trailer->db_free_rec_len = cpu_to_le16(max_rec_len);
+	if (add_to_free_list) {
+		trailer->db_free_next = dx_root->dr_free_blk;
+		dx_root->dr_free_blk = cpu_to_le64(leaf_bh->b_blocknr);
+		ocfs2_journal_dirty(handle, dx_root_bh);
+	}
+
+	/* leaf_bh was journal_accessed for us in __ocfs2_delete_entry */
+	ocfs2_journal_dirty(handle, leaf_bh);
+
+	le32_add_cpu(&dx_root->dr_num_entries, -1);
+	ocfs2_journal_dirty(handle, dx_root_bh);
+
+	ocfs2_dx_list_remove_entry(entry_list, index);
+
+	if (!ocfs2_dx_root_inline(dx_root))
+		ocfs2_journal_dirty(handle, lookup->dl_dx_leaf_bh);
+
+out:
+	return ret;
+}
+
+static inline int ocfs2_delete_entry_id(handle_t *handle,
+					struct inode *dir,
+					struct ocfs2_dir_entry *de_del,
+					struct buffer_head *bh)
+{
+	int ret;
+	struct buffer_head *di_bh = NULL;
+	struct ocfs2_dinode *di;
+	struct ocfs2_inline_data *data;
+
+	ret = ocfs2_read_inode_block(dir, &di_bh);
+	if (ret) {
+		mlog_errno(ret);
+		goto out;
+	}
+
+	di = (struct ocfs2_dinode *)di_bh->b_data;
+	data = &di->id2.i_data;
+
+	ret = __ocfs2_delete_entry(handle, dir, de_del, bh, data->id_data,
+				   i_size_read(dir));
+
+	brelse(di_bh);
+out:
+	return ret;
+}
+
+static inline int ocfs2_delete_entry_el(handle_t *handle,
+					struct inode *dir,
+					struct ocfs2_dir_entry *de_del,
+					struct buffer_head *bh)
+{
+	return __ocfs2_delete_entry(handle, dir, de_del, bh, bh->b_data,
+				    bh->b_size);
+}
+
+/*
+ * Delete a directory entry. Hide the details of directory
+ * implementation from the caller.
+ */
+int ocfs2_delete_entry(handle_t *handle,
+		       struct inode *dir,
+		       struct ocfs2_dir_lookup_result *res)
+{
+	if (ocfs2_dir_indexed(dir))
+		return ocfs2_delete_entry_dx(handle, dir, res);
+
+	if (OCFS2_I(dir)->ip_dyn_features & OCFS2_INLINE_DATA_FL)
+		return ocfs2_delete_entry_id(handle, dir, res->dl_entry,
+					     res->dl_leaf_bh);
+
+	return ocfs2_delete_entry_el(handle, dir, res->dl_entry,
+				     res->dl_leaf_bh);
+}
+
+/*
+ * Check whether 'de' has enough room to hold an entry of
+ * 'new_rec_len' bytes.
+ */
+static inline int ocfs2_dirent_would_fit(struct ocfs2_dir_entry *de,
+					 unsigned int new_rec_len)
+{
+	unsigned int de_really_used;
+
+	/* Check whether this is an empty record with enough space */
+	if (le64_to_cpu(de->inode) == 0 &&
+	    le16_to_cpu(de->rec_len) >= new_rec_len)
+		return 1;
+
+	/*
+	 * Record might have free space at the end which we can
+	 * use.
+	 */
+	de_really_used = OCFS2_DIR_REC_LEN(de->name_len);
+	if (le16_to_cpu(de->rec_len) >= (de_really_used + new_rec_len))
+	    return 1;
+
+	return 0;
+}
+
+static void ocfs2_dx_dir_leaf_insert_tail(struct ocfs2_dx_leaf *dx_leaf,
+					  struct ocfs2_dx_entry *dx_new_entry)
+{
+	int i;
+
+	i = le16_to_cpu(dx_leaf->dl_list.de_num_used);
+	dx_leaf->dl_list.de_entries[i] = *dx_new_entry;
+
+	le16_add_cpu(&dx_leaf->dl_list.de_num_used, 1);
+}
+
+static void ocfs2_dx_entry_list_insert(struct ocfs2_dx_entry_list *entry_list,
+				       struct ocfs2_dx_hinfo *hinfo,
+				       u64 dirent_blk)
+{
+	int i;
+	struct ocfs2_dx_entry *dx_entry;
+
+	i = le16_to_cpu(entry_list->de_num_used);
+	dx_entry = &entry_list->de_entries[i];
+
+	memset(dx_entry, 0, sizeof(*dx_entry));
+	dx_entry->dx_major_hash = cpu_to_le32(hinfo->major_hash);
+	dx_entry->dx_minor_hash = cpu_to_le32(hinfo->minor_hash);
+	dx_entry->dx_dirent_blk = cpu_to_le64(dirent_blk);
+
+	le16_add_cpu(&entry_list->de_num_used, 1);
+}
+
+static int __ocfs2_dx_dir_leaf_insert(struct inode *dir, handle_t *handle,
+				      struct ocfs2_dx_hinfo *hinfo,
+				      u64 dirent_blk,
+				      struct buffer_head *dx_leaf_bh)
+{
+	int ret;
+	struct ocfs2_dx_leaf *dx_leaf;
+
+	ret = ocfs2_journal_access_dl(handle, INODE_CACHE(dir), dx_leaf_bh,
+				      OCFS2_JOURNAL_ACCESS_WRITE);
+	if (ret) {
+		mlog_errno(ret);
+		goto out;
+	}
+
+	dx_leaf = (struct ocfs2_dx_leaf *)dx_leaf_bh->b_data;
+	ocfs2_dx_entry_list_insert(&dx_leaf->dl_list, hinfo, dirent_blk);
+	ocfs2_journal_dirty(handle, dx_leaf_bh);
+
+out:
+	return ret;
+}
+
+static void ocfs2_dx_inline_root_insert(struct inode *dir, handle_t *handle,
+					struct ocfs2_dx_hinfo *hinfo,
+					u64 dirent_blk,
+					struct ocfs2_dx_root_block *dx_root)
+{
+	ocfs2_dx_entry_list_insert(&dx_root->dr_entries, hinfo, dirent_blk);
+}
+
+static int ocfs2_dx_dir_insert(struct inode *dir, handle_t *handle,
+			       struct ocfs2_dir_lookup_result *lookup)
+{
+	int ret = 0;
+	struct ocfs2_dx_root_block *dx_root;
+	struct buffer_head *dx_root_bh = lookup->dl_dx_root_bh;
+
+	ret = ocfs2_journal_access_dr(handle, INODE_CACHE(dir), dx_root_bh,
+				      OCFS2_JOURNAL_ACCESS_WRITE);
+	if (ret) {
+		mlog_errno(ret);
+		goto out;
+	}
+
+	dx_root = (struct ocfs2_dx_root_block *)lookup->dl_dx_root_bh->b_data;
+	if (ocfs2_dx_root_inline(dx_root)) {
+		ocfs2_dx_inline_root_insert(dir, handle,
+					    &lookup->dl_hinfo,
+					    lookup->dl_leaf_bh->b_blocknr,
+					    dx_root);
+	} else {
+		ret = __ocfs2_dx_dir_leaf_insert(dir, handle, &lookup->dl_hinfo,
+						 lookup->dl_leaf_bh->b_blocknr,
+						 lookup->dl_dx_leaf_bh);
+		if (ret)
+			goto out;
+	}
+
+	le32_add_cpu(&dx_root->dr_num_entries, 1);
+	ocfs2_journal_dirty(handle, dx_root_bh);
+
+out:
+	return ret;
+}
+
+static void ocfs2_remove_block_from_free_list(struct inode *dir,
+				       handle_t *handle,
+				       struct ocfs2_dir_lookup_result *lookup)
+{
+	struct ocfs2_dir_block_trailer *trailer, *prev;
+	struct ocfs2_dx_root_block *dx_root;
+	struct buffer_head *bh;
+
+	trailer = ocfs2_trailer_from_bh(lookup->dl_leaf_bh, dir->i_sb);
+
+	if (ocfs2_free_list_at_root(lookup)) {
+		bh = lookup->dl_dx_root_bh;
+		dx_root = (struct ocfs2_dx_root_block *)bh->b_data;
+		dx_root->dr_free_blk = trailer->db_free_next;
+	} else {
+		bh = lookup->dl_prev_leaf_bh;
+		prev = ocfs2_trailer_from_bh(bh, dir->i_sb);
+		prev->db_free_next = trailer->db_free_next;
+	}
+
+	trailer->db_free_rec_len = cpu_to_le16(0);
+	trailer->db_free_next = cpu_to_le64(0);
+
+	ocfs2_journal_dirty(handle, bh);
+	ocfs2_journal_dirty(handle, lookup->dl_leaf_bh);
+}
+
+/*
+ * This expects that a journal write has been reserved on
+ * lookup->dl_prev_leaf_bh or lookup->dl_dx_root_bh
+ */
+static void ocfs2_recalc_free_list(struct inode *dir, handle_t *handle,
+				   struct ocfs2_dir_lookup_result *lookup)
+{
+	int max_rec_len;
+	struct ocfs2_dir_block_trailer *trailer;
+
+	/* Walk dl_leaf_bh to figure out what the new free rec_len is. */
+	max_rec_len = ocfs2_find_max_rec_len(dir->i_sb, lookup->dl_leaf_bh);
+	if (max_rec_len) {
+		/*
+		 * There's still room in this block, so no need to remove it
+		 * from the free list. In this case, we just want to update
+		 * the rec len accounting.
+		 */
+		trailer = ocfs2_trailer_from_bh(lookup->dl_leaf_bh, dir->i_sb);
+		trailer->db_free_rec_len = cpu_to_le16(max_rec_len);
+		ocfs2_journal_dirty(handle, lookup->dl_leaf_bh);
+	} else {
+		ocfs2_remove_block_from_free_list(dir, handle, lookup);
+	}
+}
+
+/* we don't always have a dentry for what we want to add, so people
+ * like orphan dir can call this instead.
+ *
+ * The lookup context must have been filled from
+ * ocfs2_prepare_dir_for_insert.
+ */
+int __ocfs2_add_entry(handle_t *handle,
+		      struct inode *dir,
+		      const char *name, int namelen,
+		      struct inode *inode, u64 blkno,
+		      struct buffer_head *parent_fe_bh,
+		      struct ocfs2_dir_lookup_result *lookup)
+{
+	unsigned long offset;
+	unsigned short rec_len;
+	struct ocfs2_dir_entry *de, *de1;
+	struct ocfs2_dinode *di = (struct ocfs2_dinode *)parent_fe_bh->b_data;
+	struct super_block *sb = dir->i_sb;
+	int retval, status;
+	unsigned int size = sb->s_blocksize;
+	struct buffer_head *insert_bh = lookup->dl_leaf_bh;
+	char *data_start = insert_bh->b_data;
+
+	if (!namelen)
+		return -EINVAL;
+
+	if (ocfs2_dir_indexed(dir)) {
+		struct buffer_head *bh;
+
+		/*
+		 * An indexed dir may require that we update the free space
+		 * list. Reserve a write to the previous node in the list so
+		 * that we don't fail later.
+		 *
+		 * XXX: This can be either a dx_root_block, or an unindexed
+		 * directory tree leaf block.
+		 */
+		if (ocfs2_free_list_at_root(lookup)) {
+			bh = lookup->dl_dx_root_bh;
+			retval = ocfs2_journal_access_dr(handle,
+						 INODE_CACHE(dir), bh,
+						 OCFS2_JOURNAL_ACCESS_WRITE);
+		} else {
+			bh = lookup->dl_prev_leaf_bh;
+			retval = ocfs2_journal_access_db(handle,
+						 INODE_CACHE(dir), bh,
+						 OCFS2_JOURNAL_ACCESS_WRITE);
+		}
+		if (retval) {
+			mlog_errno(retval);
+			return retval;
+		}
+	} else if (OCFS2_I(dir)->ip_dyn_features & OCFS2_INLINE_DATA_FL) {
+		data_start = di->id2.i_data.id_data;
+		size = i_size_read(dir);
+
+		BUG_ON(insert_bh != parent_fe_bh);
+	}
+
+	rec_len = OCFS2_DIR_REC_LEN(namelen);
+	offset = 0;
+	de = (struct ocfs2_dir_entry *) data_start;
+	while (1) {
+		BUG_ON((char *)de >= (size + data_start));
+
+		/* These checks should've already been passed by the
+		 * prepare function, but I guess we can leave them
+		 * here anyway. */
+		if (!ocfs2_check_dir_entry(dir, de, insert_bh, offset)) {
+			retval = -ENOENT;
+			goto bail;
+		}
+		if (ocfs2_match(namelen, name, de)) {
+			retval = -EEXIST;
+			goto bail;
+		}
+
+		/* We're guaranteed that we should have space, so we
+		 * can't possibly have hit the trailer...right? */
+		mlog_bug_on_msg(ocfs2_skip_dir_trailer(dir, de, offset, size),
+				"Hit dir trailer trying to insert %.*s "
+			        "(namelen %d) into directory %llu.  "
+				"offset is %lu, trailer offset is %d\n",
+				namelen, name, namelen,
+				(unsigned long long)parent_fe_bh->b_blocknr,
+				offset, ocfs2_dir_trailer_blk_off(dir->i_sb));
+
+		if (ocfs2_dirent_would_fit(de, rec_len)) {
+			dir->i_mtime = dir->i_ctime = CURRENT_TIME;
+			retval = ocfs2_mark_inode_dirty(handle, dir, parent_fe_bh);
+			if (retval < 0) {
+				mlog_errno(retval);
+				goto bail;
+			}
+
+			if (insert_bh == parent_fe_bh)
+				status = ocfs2_journal_access_di(handle,
+								 INODE_CACHE(dir),
+								 insert_bh,
+								 OCFS2_JOURNAL_ACCESS_WRITE);
+			else {
+				status = ocfs2_journal_access_db(handle,
+								 INODE_CACHE(dir),
+								 insert_bh,
+					      OCFS2_JOURNAL_ACCESS_WRITE);
+
+				if (ocfs2_dir_indexed(dir)) {
+					status = ocfs2_dx_dir_insert(dir,
+								handle,
+								lookup);
+					if (status) {
+						mlog_errno(status);
+						goto bail;
+					}
+				}
+			}
+
+			/* By now the buffer is marked for journaling */
+			offset += le16_to_cpu(de->rec_len);
+			if (le64_to_cpu(de->inode)) {
+				de1 = (struct ocfs2_dir_entry *)((char *) de +
+					OCFS2_DIR_REC_LEN(de->name_len));
+				de1->rec_len =
+					cpu_to_le16(le16_to_cpu(de->rec_len) -
+					OCFS2_DIR_REC_LEN(de->name_len));
+				de->rec_len = cpu_to_le16(OCFS2_DIR_REC_LEN(de->name_len));
+				de = de1;
+			}
+			de->file_type = OCFS2_FT_UNKNOWN;
+			if (blkno) {
+				de->inode = cpu_to_le64(blkno);
+				ocfs2_set_de_type(de, inode->i_mode);
+			} else
+				de->inode = 0;
+			de->name_len = namelen;
+			memcpy(de->name, name, namelen);
+
+			if (ocfs2_dir_indexed(dir))
+				ocfs2_recalc_free_list(dir, handle, lookup);
+
+			dir->i_version++;
+			ocfs2_journal_dirty(handle, insert_bh);
+			retval = 0;
+			goto bail;
+		}
+
+		offset += le16_to_cpu(de->rec_len);
+		de = (struct ocfs2_dir_entry *) ((char *) de + le16_to_cpu(de->rec_len));
+	}
+
+	/* when you think about it, the assert above should prevent us
+	 * from ever getting here. */
+	retval = -ENOSPC;
+bail:
+	if (retval)
+		mlog_errno(retval);
+
+	return retval;
+}
+
+static int ocfs2_dir_foreach_blk_id(struct inode *inode,
+				    u64 *f_version,
+				    struct dir_context *ctx)
+{
+	int ret, i;
+	unsigned long offset = ctx->pos;
+	struct buffer_head *di_bh = NULL;
+	struct ocfs2_dinode *di;
+	struct ocfs2_inline_data *data;
+	struct ocfs2_dir_entry *de;
+
+	ret = ocfs2_read_inode_block(inode, &di_bh);
+	if (ret) {
+		mlog(ML_ERROR, "Unable to read inode block for dir %llu\n",
+		     (unsigned long long)OCFS2_I(inode)->ip_blkno);
+		goto out;
+	}
+
+	di = (struct ocfs2_dinode *)di_bh->b_data;
+	data = &di->id2.i_data;
+
+	while (ctx->pos < i_size_read(inode)) {
+		/* If the dir block has changed since the last call to
+		 * readdir(2), then we might be pointing to an invalid
+		 * dirent right now.  Scan from the start of the block
+		 * to make sure. */
+		if (*f_version != inode->i_version) {
+			for (i = 0; i < i_size_read(inode) && i < offset; ) {
+				de = (struct ocfs2_dir_entry *)
+					(data->id_data + i);
+				/* It's too expensive to do a full
+				 * dirent test each time round this
+				 * loop, but we do have to test at
+				 * least that it is non-zero.  A
+				 * failure will be detected in the
+				 * dirent test below. */
+				if (le16_to_cpu(de->rec_len) <
+				    OCFS2_DIR_REC_LEN(1))
+					break;
+				i += le16_to_cpu(de->rec_len);
+			}
+			ctx->pos = offset = i;
+			*f_version = inode->i_version;
+		}
+
+		de = (struct ocfs2_dir_entry *) (data->id_data + ctx->pos);
+		if (!ocfs2_check_dir_entry(inode, de, di_bh, ctx->pos)) {
+			/* On error, skip the f_pos to the end. */
+			ctx->pos = i_size_read(inode);
+			break;
+		}
+		offset += le16_to_cpu(de->rec_len);
+		if (le64_to_cpu(de->inode)) {
+			unsigned char d_type = DT_UNKNOWN;
+
+			if (de->file_type < OCFS2_FT_MAX)
+				d_type = ocfs2_filetype_table[de->file_type];
+
+			if (!dir_emit(ctx, de->name, de->name_len,
+				      le64_to_cpu(de->inode), d_type))
+				goto out;
+		}
+		ctx->pos += le16_to_cpu(de->rec_len);
+	}
+out:
+	brelse(di_bh);
+	return 0;
+}
+
+/*
+ * NOTE: This function can be called against unindexed directories,
+ * and indexed ones.
+ */
+static int ocfs2_dir_foreach_blk_el(struct inode *inode,
+				    u64 *f_version,
+				    struct dir_context *ctx,
+				    bool persist)
+{
+	unsigned long offset, blk, last_ra_blk = 0;
+	int i;
+	struct buffer_head * bh, * tmp;
+	struct ocfs2_dir_entry * de;
+	struct super_block * sb = inode->i_sb;
+	unsigned int ra_sectors = 16;
+	int stored = 0;
+
+	bh = NULL;
+
+	offset = ctx->pos & (sb->s_blocksize - 1);
+
+	while (ctx->pos < i_size_read(inode)) {
+		blk = ctx->pos >> sb->s_blocksize_bits;
+		if (ocfs2_read_dir_block(inode, blk, &bh, 0)) {
+			/* Skip the corrupt dirblock and keep trying */
+			ctx->pos += sb->s_blocksize - offset;
+			continue;
+		}
+
+		/* The idea here is to begin with 8k read-ahead and to stay
+		 * 4k ahead of our current position.
+		 *
+		 * TODO: Use the pagecache for this. We just need to
+		 * make sure it's cluster-safe... */
+		if (!last_ra_blk
+		    || (((last_ra_blk - blk) << 9) <= (ra_sectors / 2))) {
+			for (i = ra_sectors >> (sb->s_blocksize_bits - 9);
+			     i > 0; i--) {
+				tmp = NULL;
+				if (!ocfs2_read_dir_block(inode, ++blk, &tmp,
+							  OCFS2_BH_READAHEAD))
+					brelse(tmp);
+			}
+			last_ra_blk = blk;
+			ra_sectors = 8;
+		}
+
+		/* If the dir block has changed since the last call to
+		 * readdir(2), then we might be pointing to an invalid
+		 * dirent right now.  Scan from the start of the block
+		 * to make sure. */
+		if (*f_version != inode->i_version) {
+			for (i = 0; i < sb->s_blocksize && i < offset; ) {
+				de = (struct ocfs2_dir_entry *) (bh->b_data + i);
+				/* It's too expensive to do a full
+				 * dirent test each time round this
+				 * loop, but we do have to test at
+				 * least that it is non-zero.  A
+				 * failure will be detected in the
+				 * dirent test below. */
+				if (le16_to_cpu(de->rec_len) <
+				    OCFS2_DIR_REC_LEN(1))
+					break;
+				i += le16_to_cpu(de->rec_len);
+			}
+			offset = i;
+			ctx->pos = (ctx->pos & ~(sb->s_blocksize - 1))
+				| offset;
+			*f_version = inode->i_version;
+		}
+
+		while (ctx->pos < i_size_read(inode)
+		       && offset < sb->s_blocksize) {
+			de = (struct ocfs2_dir_entry *) (bh->b_data + offset);
+			if (!ocfs2_check_dir_entry(inode, de, bh, offset)) {
+				/* On error, skip the f_pos to the
+				   next block. */
+				ctx->pos = (ctx->pos | (sb->s_blocksize - 1)) + 1;
+				brelse(bh);
+				continue;
+			}
+			if (le64_to_cpu(de->inode)) {
+				unsigned char d_type = DT_UNKNOWN;
+
+				if (de->file_type < OCFS2_FT_MAX)
+					d_type = ocfs2_filetype_table[de->file_type];
+				if (!dir_emit(ctx, de->name,
+						de->name_len,
+						le64_to_cpu(de->inode),
+						d_type)) {
+					brelse(bh);
+					return 0;
+				}
+				stored++;
+			}
+			offset += le16_to_cpu(de->rec_len);
+			ctx->pos += le16_to_cpu(de->rec_len);
+		}
+		offset = 0;
+		brelse(bh);
+		bh = NULL;
+		if (!persist && stored)
+			break;
+	}
+	return 0;
+}
+
+static int ocfs2_dir_foreach_blk(struct inode *inode, u64 *f_version,
+				 struct dir_context *ctx,
+				 bool persist)
+{
+	if (OCFS2_I(inode)->ip_dyn_features & OCFS2_INLINE_DATA_FL)
+		return ocfs2_dir_foreach_blk_id(inode, f_version, ctx);
+	return ocfs2_dir_foreach_blk_el(inode, f_version, ctx, persist);
+}
+
+/*
+ * This is intended to be called from inside other kernel functions,
+ * so we fake some arguments.
+ */
+int ocfs2_dir_foreach(struct inode *inode, struct dir_context *ctx)
+{
+	u64 version = inode->i_version;
+	ocfs2_dir_foreach_blk(inode, &version, ctx, true);
+	return 0;
+}
+
+/*
+ * ocfs2_readdir()
+ *
+ */
+int ocfs2_readdir(struct file *file, struct dir_context *ctx)
+{
+	int error = 0;
+	struct inode *inode = file_inode(file);
+	int lock_level = 0;
+
+	trace_ocfs2_readdir((unsigned long long)OCFS2_I(inode)->ip_blkno);
+
+	error = ocfs2_inode_lock_atime(inode, file->f_path.mnt, &lock_level);
+	if (lock_level && error >= 0) {
+		/* We release EX lock which used to update atime
+		 * and get PR lock again to reduce contention
+		 * on commonly accessed directories. */
+		ocfs2_inode_unlock(inode, 1);
+		lock_level = 0;
+		error = ocfs2_inode_lock(inode, NULL, 0);
+	}
+	if (error < 0) {
+		if (error != -ENOENT)
+			mlog_errno(error);
+		/* we haven't got any yet, so propagate the error. */
+		goto bail_nolock;
+	}
+
+	error = ocfs2_dir_foreach_blk(inode, &file->f_version, ctx, false);
+
+	ocfs2_inode_unlock(inode, lock_level);
+	if (error)
+		mlog_errno(error);
+
+bail_nolock:
+
+	return error;
+}
+
+/*
+ * NOTE: this should always be called with parent dir i_mutex taken.
+ */
+int ocfs2_find_files_on_disk(const char *name,
+			     int namelen,
+			     u64 *blkno,
+			     struct inode *inode,
+			     struct ocfs2_dir_lookup_result *lookup)
+{
+	int status = -ENOENT;
+
+	trace_ocfs2_find_files_on_disk(namelen, name, blkno,
+				(unsigned long long)OCFS2_I(inode)->ip_blkno);
+
+	status = ocfs2_find_entry(name, namelen, inode, lookup);
+	if (status)
+		goto leave;
+
+	*blkno = le64_to_cpu(lookup->dl_entry->inode);
+
+	status = 0;
+leave:
+
+	return status;
+}
+
+/*
+ * Convenience function for callers which just want the block number
+ * mapped to a name and don't require the full dirent info, etc.
+ */
+int ocfs2_lookup_ino_from_name(struct inode *dir, const char *name,
+			       int namelen, u64 *blkno)
+{
+	int ret;
+	struct ocfs2_dir_lookup_result lookup = { NULL, };
+
+	ret = ocfs2_find_files_on_disk(name, namelen, blkno, dir, &lookup);
+	ocfs2_free_dir_lookup_result(&lookup);
+
+	return ret;
+}
+
+/* Check for a name within a directory.
+ *
+ * Return 0 if the name does not exist
+ * Return -EEXIST if the directory contains the name
+ *
+ * Callers should have i_mutex + a cluster lock on dir
+ */
+int ocfs2_check_dir_for_entry(struct inode *dir,
+			      const char *name,
+			      int namelen)
+{
+	int ret = 0;
+	struct ocfs2_dir_lookup_result lookup = { NULL, };
+
+	trace_ocfs2_check_dir_for_entry(
+		(unsigned long long)OCFS2_I(dir)->ip_blkno, namelen, name);
+
+	if (ocfs2_find_entry(name, namelen, dir, &lookup) == 0) {
+		ret = -EEXIST;
+		mlog_errno(ret);
+	}
+
+	ocfs2_free_dir_lookup_result(&lookup);
+
+	return ret;
+}
+
+struct ocfs2_empty_dir_priv {
+	struct dir_context ctx;
+	unsigned seen_dot;
+	unsigned seen_dot_dot;
+	unsigned seen_other;
+	unsigned dx_dir;
+};
+static int ocfs2_empty_dir_filldir(struct dir_context *ctx, const char *name,
+				   int name_len, loff_t pos, u64 ino,
+				   unsigned type)
+{
+	struct ocfs2_empty_dir_priv *p =
+		container_of(ctx, struct ocfs2_empty_dir_priv, ctx);
+
+	/*
+	 * Check the positions of "." and ".." records to be sure
+	 * they're in the correct place.
+	 *
+	 * Indexed directories don't need to proceed past the first
+	 * two entries, so we end the scan after seeing '..'. Despite
+	 * that, we allow the scan to proceed In the event that we
+	 * have a corrupted indexed directory (no dot or dot dot
+	 * entries). This allows us to double check for existing
+	 * entries which might not have been found in the index.
+	 */
+	if (name_len == 1 && !strncmp(".", name, 1) && pos == 0) {
+		p->seen_dot = 1;
+		return 0;
+	}
+
+	if (name_len == 2 && !strncmp("..", name, 2) &&
+	    pos == OCFS2_DIR_REC_LEN(1)) {
+		p->seen_dot_dot = 1;
+
+		if (p->dx_dir && p->seen_dot)
+			return 1;
+
+		return 0;
+	}
+
+	p->seen_other = 1;
+	return 1;
+}
+
+static int ocfs2_empty_dir_dx(struct inode *inode,
+			      struct ocfs2_empty_dir_priv *priv)
+{
+	int ret;
+	struct buffer_head *di_bh = NULL;
+	struct buffer_head *dx_root_bh = NULL;
+	struct ocfs2_dinode *di;
+	struct ocfs2_dx_root_block *dx_root;
+
+	priv->dx_dir = 1;
+
+	ret = ocfs2_read_inode_block(inode, &di_bh);
+	if (ret) {
+		mlog_errno(ret);
+		goto out;
+	}
+	di = (struct ocfs2_dinode *)di_bh->b_data;
+
+	ret = ocfs2_read_dx_root(inode, di, &dx_root_bh);
+	if (ret) {
+		mlog_errno(ret);
+		goto out;
+	}
+	dx_root = (struct ocfs2_dx_root_block *)dx_root_bh->b_data;
+
+	if (le32_to_cpu(dx_root->dr_num_entries) != 2)
+		priv->seen_other = 1;
+
+out:
+	brelse(di_bh);
+	brelse(dx_root_bh);
+	return ret;
+}
+
+/*
+ * routine to check that the specified directory is empty (for rmdir)
+ *
+ * Returns 1 if dir is empty, zero otherwise.
+ *
+ * XXX: This is a performance problem for unindexed directories.
+ */
+int ocfs2_empty_dir(struct inode *inode)
+{
+	int ret;
+	struct ocfs2_empty_dir_priv priv = {
+		.ctx.actor = ocfs2_empty_dir_filldir,
+	};
+
+	if (ocfs2_dir_indexed(inode)) {
+		ret = ocfs2_empty_dir_dx(inode, &priv);
+		if (ret)
+			mlog_errno(ret);
+		/*
+		 * We still run ocfs2_dir_foreach to get the checks
+		 * for "." and "..".
+		 */
+	}
+
+	ret = ocfs2_dir_foreach(inode, &priv.ctx);
+	if (ret)
+		mlog_errno(ret);
+
+	if (!priv.seen_dot || !priv.seen_dot_dot) {
+		mlog(ML_ERROR, "bad directory (dir #%llu) - no `.' or `..'\n",
+		     (unsigned long long)OCFS2_I(inode)->ip_blkno);
+		/*
+		 * XXX: Is it really safe to allow an unlink to continue?
+		 */
+		return 1;
+	}
+
+	return !priv.seen_other;
+}
+
+/*
+ * Fills "." and ".." dirents in a new directory block. Returns dirent for
+ * "..", which might be used during creation of a directory with a trailing
+ * header. It is otherwise safe to ignore the return code.
+ */
+static struct ocfs2_dir_entry *ocfs2_fill_initial_dirents(struct inode *inode,
+							  struct inode *parent,
+							  char *start,
+							  unsigned int size)
+{
+	struct ocfs2_dir_entry *de = (struct ocfs2_dir_entry *)start;
+
+	de->inode = cpu_to_le64(OCFS2_I(inode)->ip_blkno);
+	de->name_len = 1;
+	de->rec_len =
+		cpu_to_le16(OCFS2_DIR_REC_LEN(de->name_len));
+	strcpy(de->name, ".");
+	ocfs2_set_de_type(de, S_IFDIR);
+
+	de = (struct ocfs2_dir_entry *) ((char *)de + le16_to_cpu(de->rec_len));
+	de->inode = cpu_to_le64(OCFS2_I(parent)->ip_blkno);
+	de->rec_len = cpu_to_le16(size - OCFS2_DIR_REC_LEN(1));
+	de->name_len = 2;
+	strcpy(de->name, "..");
+	ocfs2_set_de_type(de, S_IFDIR);
+
+	return de;
+}
+
+/*
+ * This works together with code in ocfs2_mknod_locked() which sets
+ * the inline-data flag and initializes the inline-data section.
+ */
+static int ocfs2_fill_new_dir_id(struct ocfs2_super *osb,
+				 handle_t *handle,
+				 struct inode *parent,
+				 struct inode *inode,
+				 struct buffer_head *di_bh)
+{
+	int ret;
+	struct ocfs2_dinode *di = (struct ocfs2_dinode *)di_bh->b_data;
+	struct ocfs2_inline_data *data = &di->id2.i_data;
+	unsigned int size = le16_to_cpu(data->id_count);
+
+	ret = ocfs2_journal_access_di(handle, INODE_CACHE(inode), di_bh,
+				      OCFS2_JOURNAL_ACCESS_WRITE);
+	if (ret) {
+		mlog_errno(ret);
+		goto out;
+	}
+
+	ocfs2_fill_initial_dirents(inode, parent, data->id_data, size);
+	ocfs2_journal_dirty(handle, di_bh);
+
+	i_size_write(inode, size);
+	set_nlink(inode, 2);
+	inode->i_blocks = ocfs2_inode_sector_count(inode);
+
+	ret = ocfs2_mark_inode_dirty(handle, inode, di_bh);
+	if (ret < 0)
+		mlog_errno(ret);
+
+out:
+	return ret;
+}
+
+static int ocfs2_fill_new_dir_el(struct ocfs2_super *osb,
+				 handle_t *handle,
+				 struct inode *parent,
+				 struct inode *inode,
+				 struct buffer_head *fe_bh,
+				 struct ocfs2_alloc_context *data_ac,
+				 struct buffer_head **ret_new_bh)
+{
+	int status;
+	unsigned int size = osb->sb->s_blocksize;
+	struct buffer_head *new_bh = NULL;
+	struct ocfs2_dir_entry *de;
+
+	if (ocfs2_new_dir_wants_trailer(inode))
+		size = ocfs2_dir_trailer_blk_off(parent->i_sb);
+
+	status = ocfs2_do_extend_dir(osb->sb, handle, inode, fe_bh,
+				     data_ac, NULL, &new_bh);
+	if (status < 0) {
+		mlog_errno(status);
+		goto bail;
+	}
+
+	ocfs2_set_new_buffer_uptodate(INODE_CACHE(inode), new_bh);
+
+	status = ocfs2_journal_access_db(handle, INODE_CACHE(inode), new_bh,
+					 OCFS2_JOURNAL_ACCESS_CREATE);
+	if (status < 0) {
+		mlog_errno(status);
+		goto bail;
+	}
+	memset(new_bh->b_data, 0, osb->sb->s_blocksize);
+
+	de = ocfs2_fill_initial_dirents(inode, parent, new_bh->b_data, size);
+	if (ocfs2_new_dir_wants_trailer(inode)) {
+		int size = le16_to_cpu(de->rec_len);
+
+		/*
+		 * Figure out the size of the hole left over after
+		 * insertion of '.' and '..'. The trailer wants this
+		 * information.
+		 */
+		size -= OCFS2_DIR_REC_LEN(2);
+		size -= sizeof(struct ocfs2_dir_block_trailer);
+
+		ocfs2_init_dir_trailer(inode, new_bh, size);
+	}
+
+	ocfs2_journal_dirty(handle, new_bh);
+
+	i_size_write(inode, inode->i_sb->s_blocksize);
+	set_nlink(inode, 2);
+	inode->i_blocks = ocfs2_inode_sector_count(inode);
+	status = ocfs2_mark_inode_dirty(handle, inode, fe_bh);
+	if (status < 0) {
+		mlog_errno(status);
+		goto bail;
+	}
+
+	status = 0;
+	if (ret_new_bh) {
+		*ret_new_bh = new_bh;
+		new_bh = NULL;
+	}
+bail:
+	brelse(new_bh);
+
+	return status;
+}
+
+static int ocfs2_dx_dir_attach_index(struct ocfs2_super *osb,
+				     handle_t *handle, struct inode *dir,
+				     struct buffer_head *di_bh,
+				     struct buffer_head *dirdata_bh,
+				     struct ocfs2_alloc_context *meta_ac,
+				     int dx_inline, u32 num_entries,
+				     struct buffer_head **ret_dx_root_bh)
+{
+	int ret;
+	struct ocfs2_dinode *di = (struct ocfs2_dinode *) di_bh->b_data;
+	u16 dr_suballoc_bit;
+	u64 suballoc_loc, dr_blkno;
+	unsigned int num_bits;
+	struct buffer_head *dx_root_bh = NULL;
+	struct ocfs2_dx_root_block *dx_root;
+	struct ocfs2_dir_block_trailer *trailer =
+		ocfs2_trailer_from_bh(dirdata_bh, dir->i_sb);
+
+	ret = ocfs2_claim_metadata(handle, meta_ac, 1, &suballoc_loc,
+				   &dr_suballoc_bit, &num_bits, &dr_blkno);
+	if (ret) {
+		mlog_errno(ret);
+		goto out;
+	}
+
+	trace_ocfs2_dx_dir_attach_index(
+				(unsigned long long)OCFS2_I(dir)->ip_blkno,
+				(unsigned long long)dr_blkno);
+
+	dx_root_bh = sb_getblk(osb->sb, dr_blkno);
+	if (dx_root_bh == NULL) {
+		ret = -ENOMEM;
+		goto out;
+	}
+	ocfs2_set_new_buffer_uptodate(INODE_CACHE(dir), dx_root_bh);
+
+	ret = ocfs2_journal_access_dr(handle, INODE_CACHE(dir), dx_root_bh,
+				      OCFS2_JOURNAL_ACCESS_CREATE);
+	if (ret < 0) {
+		mlog_errno(ret);
+		goto out;
+	}
+
+	dx_root = (struct ocfs2_dx_root_block *)dx_root_bh->b_data;
+	memset(dx_root, 0, osb->sb->s_blocksize);
+	strcpy(dx_root->dr_signature, OCFS2_DX_ROOT_SIGNATURE);
+	dx_root->dr_suballoc_slot = cpu_to_le16(meta_ac->ac_alloc_slot);
+	dx_root->dr_suballoc_loc = cpu_to_le64(suballoc_loc);
+	dx_root->dr_suballoc_bit = cpu_to_le16(dr_suballoc_bit);
+	dx_root->dr_fs_generation = cpu_to_le32(osb->fs_generation);
+	dx_root->dr_blkno = cpu_to_le64(dr_blkno);
+	dx_root->dr_dir_blkno = cpu_to_le64(OCFS2_I(dir)->ip_blkno);
+	dx_root->dr_num_entries = cpu_to_le32(num_entries);
+	if (le16_to_cpu(trailer->db_free_rec_len))
+		dx_root->dr_free_blk = cpu_to_le64(dirdata_bh->b_blocknr);
+	else
+		dx_root->dr_free_blk = cpu_to_le64(0);
+
+	if (dx_inline) {
+		dx_root->dr_flags |= OCFS2_DX_FLAG_INLINE;
+		dx_root->dr_entries.de_count =
+			cpu_to_le16(ocfs2_dx_entries_per_root(osb->sb));
+	} else {
+		dx_root->dr_list.l_count =
+			cpu_to_le16(ocfs2_extent_recs_per_dx_root(osb->sb));
+	}
+	ocfs2_journal_dirty(handle, dx_root_bh);
+
+	ret = ocfs2_journal_access_di(handle, INODE_CACHE(dir), di_bh,
+				      OCFS2_JOURNAL_ACCESS_CREATE);
+	if (ret) {
+		mlog_errno(ret);
+		goto out;
+	}
+
+	di->i_dx_root = cpu_to_le64(dr_blkno);
+
+	spin_lock(&OCFS2_I(dir)->ip_lock);
+	OCFS2_I(dir)->ip_dyn_features |= OCFS2_INDEXED_DIR_FL;
+	di->i_dyn_features = cpu_to_le16(OCFS2_I(dir)->ip_dyn_features);
+	spin_unlock(&OCFS2_I(dir)->ip_lock);
+
+	ocfs2_journal_dirty(handle, di_bh);
+
+	*ret_dx_root_bh = dx_root_bh;
+	dx_root_bh = NULL;
+
+out:
+	brelse(dx_root_bh);
+	return ret;
+}
+
+static int ocfs2_dx_dir_format_cluster(struct ocfs2_super *osb,
+				       handle_t *handle, struct inode *dir,
+				       struct buffer_head **dx_leaves,
+				       int num_dx_leaves, u64 start_blk)
+{
+	int ret, i;
+	struct ocfs2_dx_leaf *dx_leaf;
+	struct buffer_head *bh;
+
+	for (i = 0; i < num_dx_leaves; i++) {
+		bh = sb_getblk(osb->sb, start_blk + i);
+		if (bh == NULL) {
+			ret = -ENOMEM;
+			goto out;
+		}
+		dx_leaves[i] = bh;
+
+		ocfs2_set_new_buffer_uptodate(INODE_CACHE(dir), bh);
+
+		ret = ocfs2_journal_access_dl(handle, INODE_CACHE(dir), bh,
+					      OCFS2_JOURNAL_ACCESS_CREATE);
+		if (ret < 0) {
+			mlog_errno(ret);
+			goto out;
+		}
+
+		dx_leaf = (struct ocfs2_dx_leaf *) bh->b_data;
+
+		memset(dx_leaf, 0, osb->sb->s_blocksize);
+		strcpy(dx_leaf->dl_signature, OCFS2_DX_LEAF_SIGNATURE);
+		dx_leaf->dl_fs_generation = cpu_to_le32(osb->fs_generation);
+		dx_leaf->dl_blkno = cpu_to_le64(bh->b_blocknr);
+		dx_leaf->dl_list.de_count =
+			cpu_to_le16(ocfs2_dx_entries_per_leaf(osb->sb));
+
+		trace_ocfs2_dx_dir_format_cluster(
+				(unsigned long long)OCFS2_I(dir)->ip_blkno,
+				(unsigned long long)bh->b_blocknr,
+				le16_to_cpu(dx_leaf->dl_list.de_count));
+
+		ocfs2_journal_dirty(handle, bh);
+	}
+
+	ret = 0;
+out:
+	return ret;
+}
+
+/*
+ * Allocates and formats a new cluster for use in an indexed dir
+ * leaf. This version will not do the extent insert, so that it can be
+ * used by operations which need careful ordering.
+ */
+static int __ocfs2_dx_dir_new_cluster(struct inode *dir,
+				      u32 cpos, handle_t *handle,
+				      struct ocfs2_alloc_context *data_ac,
+				      struct buffer_head **dx_leaves,
+				      int num_dx_leaves, u64 *ret_phys_blkno)
+{
+	int ret;
+	u32 phys, num;
+	u64 phys_blkno;
+	struct ocfs2_super *osb = OCFS2_SB(dir->i_sb);
+
+	/*
+	 * XXX: For create, this should claim cluster for the index
+	 * *before* the unindexed insert so that we have a better
+	 * chance of contiguousness as the directory grows in number
+	 * of entries.
+	 */
+	ret = __ocfs2_claim_clusters(handle, data_ac, 1, 1, &phys, &num);
+	if (ret) {
+		mlog_errno(ret);
+		goto out;
+	}
+
+	/*
+	 * Format the new cluster first. That way, we're inserting
+	 * valid data.
+	 */
+	phys_blkno = ocfs2_clusters_to_blocks(osb->sb, phys);
+	ret = ocfs2_dx_dir_format_cluster(osb, handle, dir, dx_leaves,
+					  num_dx_leaves, phys_blkno);
+	if (ret) {
+		mlog_errno(ret);
+		goto out;
+	}
+
+	*ret_phys_blkno = phys_blkno;
+out:
+	return ret;
+}
+
+static int ocfs2_dx_dir_new_cluster(struct inode *dir,
+				    struct ocfs2_extent_tree *et,
+				    u32 cpos, handle_t *handle,
+				    struct ocfs2_alloc_context *data_ac,
+				    struct ocfs2_alloc_context *meta_ac,
+				    struct buffer_head **dx_leaves,
+				    int num_dx_leaves)
+{
+	int ret;
+	u64 phys_blkno;
+
+	ret = __ocfs2_dx_dir_new_cluster(dir, cpos, handle, data_ac, dx_leaves,
+					 num_dx_leaves, &phys_blkno);
+	if (ret) {
+		mlog_errno(ret);
+		goto out;
+	}
+
+	ret = ocfs2_insert_extent(handle, et, cpos, phys_blkno, 1, 0,
+				  meta_ac);
+	if (ret)
+		mlog_errno(ret);
+out:
+	return ret;
+}
+
+static struct buffer_head **ocfs2_dx_dir_kmalloc_leaves(struct super_block *sb,
+							int *ret_num_leaves)
+{
+	int num_dx_leaves = ocfs2_clusters_to_blocks(sb, 1);
+	struct buffer_head **dx_leaves;
+
+	dx_leaves = kcalloc(num_dx_leaves, sizeof(struct buffer_head *),
+			    GFP_NOFS);
+	if (dx_leaves && ret_num_leaves)
+		*ret_num_leaves = num_dx_leaves;
+
+	return dx_leaves;
+}
+
+static int ocfs2_fill_new_dir_dx(struct ocfs2_super *osb,
+				 handle_t *handle,
+				 struct inode *parent,
+				 struct inode *inode,
+				 struct buffer_head *di_bh,
+				 struct ocfs2_alloc_context *data_ac,
+				 struct ocfs2_alloc_context *meta_ac)
+{
+	int ret;
+	struct buffer_head *leaf_bh = NULL;
+	struct buffer_head *dx_root_bh = NULL;
+	struct ocfs2_dx_hinfo hinfo;
+	struct ocfs2_dx_root_block *dx_root;
+	struct ocfs2_dx_entry_list *entry_list;
+
+	/*
+	 * Our strategy is to create the directory as though it were
+	 * unindexed, then add the index block. This works with very
+	 * little complication since the state of a new directory is a
+	 * very well known quantity.
+	 *
+	 * Essentially, we have two dirents ("." and ".."), in the 1st
+	 * block which need indexing. These are easily inserted into
+	 * the index block.
+	 */
+
+	ret = ocfs2_fill_new_dir_el(osb, handle, parent, inode, di_bh,
+				    data_ac, &leaf_bh);
+	if (ret) {
+		mlog_errno(ret);
+		goto out;
+	}
+
+	ret = ocfs2_dx_dir_attach_index(osb, handle, inode, di_bh, leaf_bh,
+					meta_ac, 1, 2, &dx_root_bh);
+	if (ret) {
+		mlog_errno(ret);
+		goto out;
+	}
+	dx_root = (struct ocfs2_dx_root_block *)dx_root_bh->b_data;
+	entry_list = &dx_root->dr_entries;
+
+	/* Buffer has been journaled for us by ocfs2_dx_dir_attach_index */
+	ocfs2_dx_dir_name_hash(inode, ".", 1, &hinfo);
+	ocfs2_dx_entry_list_insert(entry_list, &hinfo, leaf_bh->b_blocknr);
+
+	ocfs2_dx_dir_name_hash(inode, "..", 2, &hinfo);
+	ocfs2_dx_entry_list_insert(entry_list, &hinfo, leaf_bh->b_blocknr);
+
+out:
+	brelse(dx_root_bh);
+	brelse(leaf_bh);
+	return ret;
+}
+
+int ocfs2_fill_new_dir(struct ocfs2_super *osb,
+		       handle_t *handle,
+		       struct inode *parent,
+		       struct inode *inode,
+		       struct buffer_head *fe_bh,
+		       struct ocfs2_alloc_context *data_ac,
+		       struct ocfs2_alloc_context *meta_ac)
+
+{
+	BUG_ON(!ocfs2_supports_inline_data(osb) && data_ac == NULL);
+
+	if (OCFS2_I(inode)->ip_dyn_features & OCFS2_INLINE_DATA_FL)
+		return ocfs2_fill_new_dir_id(osb, handle, parent, inode, fe_bh);
+
+	if (ocfs2_supports_indexed_dirs(osb))
+		return ocfs2_fill_new_dir_dx(osb, handle, parent, inode, fe_bh,
+					     data_ac, meta_ac);
+
+	return ocfs2_fill_new_dir_el(osb, handle, parent, inode, fe_bh,
+				     data_ac, NULL);
+}
+
+static int ocfs2_dx_dir_index_block(struct inode *dir,
+				    handle_t *handle,
+				    struct buffer_head **dx_leaves,
+				    int num_dx_leaves,
+				    u32 *num_dx_entries,
+				    struct buffer_head *dirent_bh)
+{
+	int ret = 0, namelen, i;
+	char *de_buf, *limit;
+	struct ocfs2_dir_entry *de;
+	struct buffer_head *dx_leaf_bh;
+	struct ocfs2_dx_hinfo hinfo;
+	u64 dirent_blk = dirent_bh->b_blocknr;
+
+	de_buf = dirent_bh->b_data;
+	limit = de_buf + dir->i_sb->s_blocksize;
+
+	while (de_buf < limit) {
+		de = (struct ocfs2_dir_entry *)de_buf;
+
+		namelen = de->name_len;
+		if (!namelen || !de->inode)
+			goto inc;
+
+		ocfs2_dx_dir_name_hash(dir, de->name, namelen, &hinfo);
+
+		i = ocfs2_dx_dir_hash_idx(OCFS2_SB(dir->i_sb), &hinfo);
+		dx_leaf_bh = dx_leaves[i];
+
+		ret = __ocfs2_dx_dir_leaf_insert(dir, handle, &hinfo,
+						 dirent_blk, dx_leaf_bh);
+		if (ret) {
+			mlog_errno(ret);
+			goto out;
+		}
+
+		*num_dx_entries = *num_dx_entries + 1;
+
+inc:
+		de_buf += le16_to_cpu(de->rec_len);
+	}
+
+out:
+	return ret;
+}
+
+/*
+ * XXX: This expects dx_root_bh to already be part of the transaction.
+ */
+static void ocfs2_dx_dir_index_root_block(struct inode *dir,
+					 struct buffer_head *dx_root_bh,
+					 struct buffer_head *dirent_bh)
+{
+	char *de_buf, *limit;
+	struct ocfs2_dx_root_block *dx_root;
+	struct ocfs2_dir_entry *de;
+	struct ocfs2_dx_hinfo hinfo;
+	u64 dirent_blk = dirent_bh->b_blocknr;
+
+	dx_root = (struct ocfs2_dx_root_block *)dx_root_bh->b_data;
+
+	de_buf = dirent_bh->b_data;
+	limit = de_buf + dir->i_sb->s_blocksize;
+
+	while (de_buf < limit) {
+		de = (struct ocfs2_dir_entry *)de_buf;
+
+		if (!de->name_len || !de->inode)
+			goto inc;
+
+		ocfs2_dx_dir_name_hash(dir, de->name, de->name_len, &hinfo);
+
+		trace_ocfs2_dx_dir_index_root_block(
+				(unsigned long long)dir->i_ino,
+				hinfo.major_hash, hinfo.minor_hash,
+				de->name_len, de->name,
+				le16_to_cpu(dx_root->dr_entries.de_num_used));
+
+		ocfs2_dx_entry_list_insert(&dx_root->dr_entries, &hinfo,
+					   dirent_blk);
+
+		le32_add_cpu(&dx_root->dr_num_entries, 1);
+inc:
+		de_buf += le16_to_cpu(de->rec_len);
+	}
+}
+
+/*
+ * Count the number of inline directory entries in di_bh and compare
+ * them against the number of entries we can hold in an inline dx root
+ * block.
+ */
+static int ocfs2_new_dx_should_be_inline(struct inode *dir,
+					 struct buffer_head *di_bh)
+{
+	int dirent_count = 0;
+	char *de_buf, *limit;
+	struct ocfs2_dir_entry *de;
+	struct ocfs2_dinode *di = (struct ocfs2_dinode *)di_bh->b_data;
+
+	de_buf = di->id2.i_data.id_data;
+	limit = de_buf + i_size_read(dir);
+
+	while (de_buf < limit) {
+		de = (struct ocfs2_dir_entry *)de_buf;
+
+		if (de->name_len && de->inode)
+			dirent_count++;
+
+		de_buf += le16_to_cpu(de->rec_len);
+	}
+
+	/* We are careful to leave room for one extra record. */
+	return dirent_count < ocfs2_dx_entries_per_root(dir->i_sb);
+}
+
+/*
+ * Expand rec_len of the rightmost dirent in a directory block so that it
+ * contains the end of our valid space for dirents. We do this during
+ * expansion from an inline directory to one with extents. The first dir block
+ * in that case is taken from the inline data portion of the inode block.
+ *
+ * This will also return the largest amount of contiguous space for a dirent
+ * in the block. That value is *not* necessarily the last dirent, even after
+ * expansion. The directory indexing code wants this value for free space
+ * accounting. We do this here since we're already walking the entire dir
+ * block.
+ *
+ * We add the dir trailer if this filesystem wants it.
+ */
+static unsigned int ocfs2_expand_last_dirent(char *start, unsigned int old_size,
+					     struct inode *dir)
+{
+	struct super_block *sb = dir->i_sb;
+	struct ocfs2_dir_entry *de;
+	struct ocfs2_dir_entry *prev_de;
+	char *de_buf, *limit;
+	unsigned int new_size = sb->s_blocksize;
+	unsigned int bytes, this_hole;
+	unsigned int largest_hole = 0;
+
+	if (ocfs2_new_dir_wants_trailer(dir))
+		new_size = ocfs2_dir_trailer_blk_off(sb);
+
+	bytes = new_size - old_size;
+
+	limit = start + old_size;
+	de_buf = start;
+	de = (struct ocfs2_dir_entry *)de_buf;
+	do {
+		this_hole = ocfs2_figure_dirent_hole(de);
+		if (this_hole > largest_hole)
+			largest_hole = this_hole;
+
+		prev_de = de;
+		de_buf += le16_to_cpu(de->rec_len);
+		de = (struct ocfs2_dir_entry *)de_buf;
+	} while (de_buf < limit);
+
+	le16_add_cpu(&prev_de->rec_len, bytes);
+
+	/* We need to double check this after modification of the final
+	 * dirent. */
+	this_hole = ocfs2_figure_dirent_hole(prev_de);
+	if (this_hole > largest_hole)
+		largest_hole = this_hole;
+
+	if (largest_hole >= OCFS2_DIR_MIN_REC_LEN)
+		return largest_hole;
+	return 0;
+}
+
+/*
+ * We allocate enough clusters to fulfill "blocks_wanted", but set
+ * i_size to exactly one block. Ocfs2_extend_dir() will handle the
+ * rest automatically for us.
+ *
+ * *first_block_bh is a pointer to the 1st data block allocated to the
+ *  directory.
+ */
+static int ocfs2_expand_inline_dir(struct inode *dir, struct buffer_head *di_bh,
+				   unsigned int blocks_wanted,
+				   struct ocfs2_dir_lookup_result *lookup,
+				   struct buffer_head **first_block_bh)
+{
+	u32 alloc, dx_alloc, bit_off, len, num_dx_entries = 0;
+	struct super_block *sb = dir->i_sb;
+	int ret, i, num_dx_leaves = 0, dx_inline = 0,
+		credits = ocfs2_inline_to_extents_credits(sb);
+	u64 dx_insert_blkno, blkno,
+		bytes = blocks_wanted << sb->s_blocksize_bits;
+	struct ocfs2_super *osb = OCFS2_SB(dir->i_sb);
+	struct ocfs2_inode_info *oi = OCFS2_I(dir);
+	struct ocfs2_alloc_context *data_ac = NULL;
+	struct ocfs2_alloc_context *meta_ac = NULL;
+	struct buffer_head *dirdata_bh = NULL;
+	struct buffer_head *dx_root_bh = NULL;
+	struct buffer_head **dx_leaves = NULL;
+	struct ocfs2_dinode *di = (struct ocfs2_dinode *)di_bh->b_data;
+	handle_t *handle;
+	struct ocfs2_extent_tree et;
+	struct ocfs2_extent_tree dx_et;
+	int did_quota = 0, bytes_allocated = 0;
+
+	ocfs2_init_dinode_extent_tree(&et, INODE_CACHE(dir), di_bh);
+
+	alloc = ocfs2_clusters_for_bytes(sb, bytes);
+	dx_alloc = 0;
+
+	down_write(&oi->ip_alloc_sem);
+
+	if (ocfs2_supports_indexed_dirs(osb)) {
+		credits += ocfs2_add_dir_index_credits(sb);
+
+		dx_inline = ocfs2_new_dx_should_be_inline(dir, di_bh);
+		if (!dx_inline) {
+			/* Add one more cluster for an index leaf */
+			dx_alloc++;
+			dx_leaves = ocfs2_dx_dir_kmalloc_leaves(sb,
+								&num_dx_leaves);
+			if (!dx_leaves) {
+				ret = -ENOMEM;
+				mlog_errno(ret);
+				goto out;
+			}
+		}
+
+		/* This gets us the dx_root */
+		ret = ocfs2_reserve_new_metadata_blocks(osb, 1, &meta_ac);
+		if (ret) {
+			mlog_errno(ret);
+			goto out;
+		}
+	}
+
+	/*
+	 * We should never need more than 2 clusters for the unindexed
+	 * tree - maximum dirent size is far less than one block. In
+	 * fact, the only time we'd need more than one cluster is if
+	 * blocksize == clustersize and the dirent won't fit in the
+	 * extra space that the expansion to a single block gives. As
+	 * of today, that only happens on 4k/4k file systems.
+	 */
+	BUG_ON(alloc > 2);
+
+	ret = ocfs2_reserve_clusters(osb, alloc + dx_alloc, &data_ac);
+	if (ret) {
+		mlog_errno(ret);
+		goto out;
+	}
+
+	/*
+	 * Prepare for worst case allocation scenario of two separate
+	 * extents in the unindexed tree.
+	 */
+	if (alloc == 2)
+		credits += OCFS2_SUBALLOC_ALLOC;
+
+	handle = ocfs2_start_trans(osb, credits);
+	if (IS_ERR(handle)) {
+		ret = PTR_ERR(handle);
+		mlog_errno(ret);
+		goto out;
+	}
+
+	ret = dquot_alloc_space_nodirty(dir,
+		ocfs2_clusters_to_bytes(osb->sb, alloc + dx_alloc));
+	if (ret)
+		goto out_commit;
+	did_quota = 1;
+
+	if (ocfs2_supports_indexed_dirs(osb) && !dx_inline) {
+		/*
+		 * Allocate our index cluster first, to maximize the
+		 * possibility that unindexed leaves grow
+		 * contiguously.
+		 */
+		ret = __ocfs2_dx_dir_new_cluster(dir, 0, handle, data_ac,
+						 dx_leaves, num_dx_leaves,
+						 &dx_insert_blkno);
+		if (ret) {
+			mlog_errno(ret);
+			goto out_commit;
+		}
+		bytes_allocated += ocfs2_clusters_to_bytes(dir->i_sb, 1);
+	}
+
+	/*
+	 * Try to claim as many clusters as the bitmap can give though
+	 * if we only get one now, that's enough to continue. The rest
+	 * will be claimed after the conversion to extents.
+	 */
+	if (ocfs2_dir_resv_allowed(osb))
+		data_ac->ac_resv = &oi->ip_la_data_resv;
+	ret = ocfs2_claim_clusters(handle, data_ac, 1, &bit_off, &len);
+	if (ret) {
+		mlog_errno(ret);
+		goto out_commit;
+	}
+	bytes_allocated += ocfs2_clusters_to_bytes(dir->i_sb, 1);
+
+	/*
+	 * Operations are carefully ordered so that we set up the new
+	 * data block first. The conversion from inline data to
+	 * extents follows.
+	 */
+	blkno = ocfs2_clusters_to_blocks(dir->i_sb, bit_off);
+	dirdata_bh = sb_getblk(sb, blkno);
+	if (!dirdata_bh) {
+		ret = -ENOMEM;
+		mlog_errno(ret);
+		goto out_commit;
+	}
+
+	ocfs2_set_new_buffer_uptodate(INODE_CACHE(dir), dirdata_bh);
+
+	ret = ocfs2_journal_access_db(handle, INODE_CACHE(dir), dirdata_bh,
+				      OCFS2_JOURNAL_ACCESS_CREATE);
+	if (ret) {
+		mlog_errno(ret);
+		goto out_commit;
+	}
+
+	memcpy(dirdata_bh->b_data, di->id2.i_data.id_data, i_size_read(dir));
+	memset(dirdata_bh->b_data + i_size_read(dir), 0,
+	       sb->s_blocksize - i_size_read(dir));
+	i = ocfs2_expand_last_dirent(dirdata_bh->b_data, i_size_read(dir), dir);
+	if (ocfs2_new_dir_wants_trailer(dir)) {
+		/*
+		 * Prepare the dir trailer up front. It will otherwise look
+		 * like a valid dirent. Even if inserting the index fails
+		 * (unlikely), then all we'll have done is given first dir
+		 * block a small amount of fragmentation.
+		 */
+		ocfs2_init_dir_trailer(dir, dirdata_bh, i);
+	}
+
+	ocfs2_update_inode_fsync_trans(handle, dir, 1);
+	ocfs2_journal_dirty(handle, dirdata_bh);
+
+	if (ocfs2_supports_indexed_dirs(osb) && !dx_inline) {
+		/*
+		 * Dx dirs with an external cluster need to do this up
+		 * front. Inline dx root's get handled later, after
+		 * we've allocated our root block. We get passed back
+		 * a total number of items so that dr_num_entries can
+		 * be correctly set once the dx_root has been
+		 * allocated.
+		 */
+		ret = ocfs2_dx_dir_index_block(dir, handle, dx_leaves,
+					       num_dx_leaves, &num_dx_entries,
+					       dirdata_bh);
+		if (ret) {
+			mlog_errno(ret);
+			goto out_commit;
+		}
+	}
+
+	/*
+	 * Set extent, i_size, etc on the directory. After this, the
+	 * inode should contain the same exact dirents as before and
+	 * be fully accessible from system calls.
+	 *
+	 * We let the later dirent insert modify c/mtime - to the user
+	 * the data hasn't changed.
+	 */
+	ret = ocfs2_journal_access_di(handle, INODE_CACHE(dir), di_bh,
+				      OCFS2_JOURNAL_ACCESS_CREATE);
+	if (ret) {
+		mlog_errno(ret);
+		goto out_commit;
+	}
+
+	spin_lock(&oi->ip_lock);
+	oi->ip_dyn_features &= ~OCFS2_INLINE_DATA_FL;
+	di->i_dyn_features = cpu_to_le16(oi->ip_dyn_features);
+	spin_unlock(&oi->ip_lock);
+
+	ocfs2_dinode_new_extent_list(dir, di);
+
+	i_size_write(dir, sb->s_blocksize);
+	dir->i_mtime = dir->i_ctime = CURRENT_TIME;
+
+	di->i_size = cpu_to_le64(sb->s_blocksize);
+	di->i_ctime = di->i_mtime = cpu_to_le64(dir->i_ctime.tv_sec);
+	di->i_ctime_nsec = di->i_mtime_nsec = cpu_to_le32(dir->i_ctime.tv_nsec);
+	ocfs2_update_inode_fsync_trans(handle, dir, 1);
+
+	/*
+	 * This should never fail as our extent list is empty and all
+	 * related blocks have been journaled already.
+	 */
+	ret = ocfs2_insert_extent(handle, &et, 0, blkno, len,
+				  0, NULL);
+	if (ret) {
+		mlog_errno(ret);
+		goto out_commit;
+	}
+
+	/*
+	 * Set i_blocks after the extent insert for the most up to
+	 * date ip_clusters value.
+	 */
+	dir->i_blocks = ocfs2_inode_sector_count(dir);
+
+	ocfs2_journal_dirty(handle, di_bh);
+
+	if (ocfs2_supports_indexed_dirs(osb)) {
+		ret = ocfs2_dx_dir_attach_index(osb, handle, dir, di_bh,
+						dirdata_bh, meta_ac, dx_inline,
+						num_dx_entries, &dx_root_bh);
+		if (ret) {
+			mlog_errno(ret);
+			goto out_commit;
+		}
+
+		if (dx_inline) {
+			ocfs2_dx_dir_index_root_block(dir, dx_root_bh,
+						      dirdata_bh);
+		} else {
+			ocfs2_init_dx_root_extent_tree(&dx_et,
+						       INODE_CACHE(dir),
+						       dx_root_bh);
+			ret = ocfs2_insert_extent(handle, &dx_et, 0,
+						  dx_insert_blkno, 1, 0, NULL);
+			if (ret)
+				mlog_errno(ret);
+		}
+	}
+
+	/*
+	 * We asked for two clusters, but only got one in the 1st
+	 * pass. Claim the 2nd cluster as a separate extent.
+	 */
+	if (alloc > len) {
+		ret = ocfs2_claim_clusters(handle, data_ac, 1, &bit_off,
+					   &len);
+		if (ret) {
+			mlog_errno(ret);
+			goto out_commit;
+		}
+		blkno = ocfs2_clusters_to_blocks(dir->i_sb, bit_off);
+
+		ret = ocfs2_insert_extent(handle, &et, 1,
+					  blkno, len, 0, NULL);
+		if (ret) {
+			mlog_errno(ret);
+			goto out_commit;
+		}
+		bytes_allocated += ocfs2_clusters_to_bytes(dir->i_sb, 1);
+	}
+
+	*first_block_bh = dirdata_bh;
+	dirdata_bh = NULL;
+	if (ocfs2_supports_indexed_dirs(osb)) {
+		unsigned int off;
+
+		if (!dx_inline) {
+			/*
+			 * We need to return the correct block within the
+			 * cluster which should hold our entry.
+			 */
+			off = ocfs2_dx_dir_hash_idx(OCFS2_SB(dir->i_sb),
+						    &lookup->dl_hinfo);
+			get_bh(dx_leaves[off]);
+			lookup->dl_dx_leaf_bh = dx_leaves[off];
+		}
+		lookup->dl_dx_root_bh = dx_root_bh;
+		dx_root_bh = NULL;
+	}
+
+out_commit:
+	if (ret < 0 && did_quota)
+		dquot_free_space_nodirty(dir, bytes_allocated);
+
+	ocfs2_commit_trans(osb, handle);
+
+out:
+	up_write(&oi->ip_alloc_sem);
+	if (data_ac)
+		ocfs2_free_alloc_context(data_ac);
+	if (meta_ac)
+		ocfs2_free_alloc_context(meta_ac);
+
+	if (dx_leaves) {
+		for (i = 0; i < num_dx_leaves; i++)
+			brelse(dx_leaves[i]);
+		kfree(dx_leaves);
+	}
+
+	brelse(dirdata_bh);
+	brelse(dx_root_bh);
+
+	return ret;
+}
+
+/* returns a bh of the 1st new block in the allocation. */
+static int ocfs2_do_extend_dir(struct super_block *sb,
+			       handle_t *handle,
+			       struct inode *dir,
+			       struct buffer_head *parent_fe_bh,
+			       struct ocfs2_alloc_context *data_ac,
+			       struct ocfs2_alloc_context *meta_ac,
+			       struct buffer_head **new_bh)
+{
+	int status;
+	int extend, did_quota = 0;
+	u64 p_blkno, v_blkno;
+
+	spin_lock(&OCFS2_I(dir)->ip_lock);
+	extend = (i_size_read(dir) == ocfs2_clusters_to_bytes(sb, OCFS2_I(dir)->ip_clusters));
+	spin_unlock(&OCFS2_I(dir)->ip_lock);
+
+	if (extend) {
+		u32 offset = OCFS2_I(dir)->ip_clusters;
+
+		status = dquot_alloc_space_nodirty(dir,
+					ocfs2_clusters_to_bytes(sb, 1));
+		if (status)
+			goto bail;
+		did_quota = 1;
+
+		status = ocfs2_add_inode_data(OCFS2_SB(sb), dir, &offset,
+					      1, 0, parent_fe_bh, handle,
+					      data_ac, meta_ac, NULL);
+		BUG_ON(status == -EAGAIN);
+		if (status < 0) {
+			mlog_errno(status);
+			goto bail;
+		}
+	}
+
+	v_blkno = ocfs2_blocks_for_bytes(sb, i_size_read(dir));
+	status = ocfs2_extent_map_get_blocks(dir, v_blkno, &p_blkno, NULL, NULL);
+	if (status < 0) {
+		mlog_errno(status);
+		goto bail;
+	}
+
+	*new_bh = sb_getblk(sb, p_blkno);
+	if (!*new_bh) {
+		status = -ENOMEM;
+		mlog_errno(status);
+		goto bail;
+	}
+	status = 0;
+bail:
+	if (did_quota && status < 0)
+		dquot_free_space_nodirty(dir, ocfs2_clusters_to_bytes(sb, 1));
+	return status;
+}
+
+/*
+ * Assumes you already have a cluster lock on the directory.
+ *
+ * 'blocks_wanted' is only used if we have an inline directory which
+ * is to be turned into an extent based one. The size of the dirent to
+ * insert might be larger than the space gained by growing to just one
+ * block, so we may have to grow the inode by two blocks in that case.
+ *
+ * If the directory is already indexed, dx_root_bh must be provided.
+ */
+static int ocfs2_extend_dir(struct ocfs2_super *osb,
+			    struct inode *dir,
+			    struct buffer_head *parent_fe_bh,
+			    unsigned int blocks_wanted,
+			    struct ocfs2_dir_lookup_result *lookup,
+			    struct buffer_head **new_de_bh)
+{
+	int status = 0;
+	int credits, num_free_extents, drop_alloc_sem = 0;
+	loff_t dir_i_size;
+	struct ocfs2_dinode *fe = (struct ocfs2_dinode *) parent_fe_bh->b_data;
+	struct ocfs2_extent_list *el = &fe->id2.i_list;
+	struct ocfs2_alloc_context *data_ac = NULL;
+	struct ocfs2_alloc_context *meta_ac = NULL;
+	handle_t *handle = NULL;
+	struct buffer_head *new_bh = NULL;
+	struct ocfs2_dir_entry * de;
+	struct super_block *sb = osb->sb;
+	struct ocfs2_extent_tree et;
+	struct buffer_head *dx_root_bh = lookup->dl_dx_root_bh;
+
+	if (OCFS2_I(dir)->ip_dyn_features & OCFS2_INLINE_DATA_FL) {
+		/*
+		 * This would be a code error as an inline directory should
+		 * never have an index root.
+		 */
+		BUG_ON(dx_root_bh);
+
+		status = ocfs2_expand_inline_dir(dir, parent_fe_bh,
+						 blocks_wanted, lookup,
+						 &new_bh);
+		if (status) {
+			mlog_errno(status);
+			goto bail;
+		}
+
+		/* Expansion from inline to an indexed directory will
+		 * have given us this. */
+		dx_root_bh = lookup->dl_dx_root_bh;
+
+		if (blocks_wanted == 1) {
+			/*
+			 * If the new dirent will fit inside the space
+			 * created by pushing out to one block, then
+			 * we can complete the operation
+			 * here. Otherwise we have to expand i_size
+			 * and format the 2nd block below.
+			 */
+			BUG_ON(new_bh == NULL);
+			goto bail_bh;
+		}
+
+		/*
+		 * Get rid of 'new_bh' - we want to format the 2nd
+		 * data block and return that instead.
+		 */
+		brelse(new_bh);
+		new_bh = NULL;
+
+		down_write(&OCFS2_I(dir)->ip_alloc_sem);
+		drop_alloc_sem = 1;
+		dir_i_size = i_size_read(dir);
+		credits = OCFS2_SIMPLE_DIR_EXTEND_CREDITS;
+		goto do_extend;
+	}
+
+	down_write(&OCFS2_I(dir)->ip_alloc_sem);
+	drop_alloc_sem = 1;
+	dir_i_size = i_size_read(dir);
+	trace_ocfs2_extend_dir((unsigned long long)OCFS2_I(dir)->ip_blkno,
+			       dir_i_size);
+
+	/* dir->i_size is always block aligned. */
+	spin_lock(&OCFS2_I(dir)->ip_lock);
+	if (dir_i_size == ocfs2_clusters_to_bytes(sb, OCFS2_I(dir)->ip_clusters)) {
+		spin_unlock(&OCFS2_I(dir)->ip_lock);
+		ocfs2_init_dinode_extent_tree(&et, INODE_CACHE(dir),
+					      parent_fe_bh);
+		num_free_extents = ocfs2_num_free_extents(osb, &et);
+		if (num_free_extents < 0) {
+			status = num_free_extents;
+			mlog_errno(status);
+			goto bail;
+		}
+
+		if (!num_free_extents) {
+			status = ocfs2_reserve_new_metadata(osb, el, &meta_ac);
+			if (status < 0) {
+				if (status != -ENOSPC)
+					mlog_errno(status);
+				goto bail;
+			}
+		}
+
+		status = ocfs2_reserve_clusters(osb, 1, &data_ac);
+		if (status < 0) {
+			if (status != -ENOSPC)
+				mlog_errno(status);
+			goto bail;
+		}
+
+		if (ocfs2_dir_resv_allowed(osb))
+			data_ac->ac_resv = &OCFS2_I(dir)->ip_la_data_resv;
+
+		credits = ocfs2_calc_extend_credits(sb, el);
+	} else {
+		spin_unlock(&OCFS2_I(dir)->ip_lock);
+		credits = OCFS2_SIMPLE_DIR_EXTEND_CREDITS;
+	}
+
+do_extend:
+	if (ocfs2_dir_indexed(dir))
+		credits++; /* For attaching the new dirent block to the
+			    * dx_root */
+
+	handle = ocfs2_start_trans(osb, credits);
+	if (IS_ERR(handle)) {
+		status = PTR_ERR(handle);
+		handle = NULL;
+		mlog_errno(status);
+		goto bail;
+	}
+
+	status = ocfs2_do_extend_dir(osb->sb, handle, dir, parent_fe_bh,
+				     data_ac, meta_ac, &new_bh);
+	if (status < 0) {
+		mlog_errno(status);
+		goto bail;
+	}
+
+	ocfs2_set_new_buffer_uptodate(INODE_CACHE(dir), new_bh);
+
+	status = ocfs2_journal_access_db(handle, INODE_CACHE(dir), new_bh,
+					 OCFS2_JOURNAL_ACCESS_CREATE);
+	if (status < 0) {
+		mlog_errno(status);
+		goto bail;
+	}
+	memset(new_bh->b_data, 0, sb->s_blocksize);
+
+	de = (struct ocfs2_dir_entry *) new_bh->b_data;
+	de->inode = 0;
+	if (ocfs2_supports_dir_trailer(dir)) {
+		de->rec_len = cpu_to_le16(ocfs2_dir_trailer_blk_off(sb));
+
+		ocfs2_init_dir_trailer(dir, new_bh, le16_to_cpu(de->rec_len));
+
+		if (ocfs2_dir_indexed(dir)) {
+			status = ocfs2_dx_dir_link_trailer(dir, handle,
+							   dx_root_bh, new_bh);
+			if (status) {
+				mlog_errno(status);
+				goto bail;
+			}
+		}
+	} else {
+		de->rec_len = cpu_to_le16(sb->s_blocksize);
+	}
+	ocfs2_update_inode_fsync_trans(handle, dir, 1);
+	ocfs2_journal_dirty(handle, new_bh);
+
+	dir_i_size += dir->i_sb->s_blocksize;
+	i_size_write(dir, dir_i_size);
+	dir->i_blocks = ocfs2_inode_sector_count(dir);
+	status = ocfs2_mark_inode_dirty(handle, dir, parent_fe_bh);
+	if (status < 0) {
+		mlog_errno(status);
+		goto bail;
+	}
+
+bail_bh:
+	*new_de_bh = new_bh;
+	get_bh(*new_de_bh);
+bail:
+	if (handle)
+		ocfs2_commit_trans(osb, handle);
+	if (drop_alloc_sem)
+		up_write(&OCFS2_I(dir)->ip_alloc_sem);
+
+	if (data_ac)
+		ocfs2_free_alloc_context(data_ac);
+	if (meta_ac)
+		ocfs2_free_alloc_context(meta_ac);
+
+	brelse(new_bh);
+
+	return status;
+}
+
+static int ocfs2_find_dir_space_id(struct inode *dir, struct buffer_head *di_bh,
+				   const char *name, int namelen,
+				   struct buffer_head **ret_de_bh,
+				   unsigned int *blocks_wanted)
+{
+	int ret;
+	struct super_block *sb = dir->i_sb;
+	struct ocfs2_dinode *di = (struct ocfs2_dinode *)di_bh->b_data;
+	struct ocfs2_dir_entry *de, *last_de = NULL;
+	char *de_buf, *limit;
+	unsigned long offset = 0;
+	unsigned int rec_len, new_rec_len, free_space = dir->i_sb->s_blocksize;
+
+	/*
+	 * This calculates how many free bytes we'd have in block zero, should
+	 * this function force expansion to an extent tree.
+	 */
+	if (ocfs2_new_dir_wants_trailer(dir))
+		free_space = ocfs2_dir_trailer_blk_off(sb) - i_size_read(dir);
+	else
+		free_space = dir->i_sb->s_blocksize - i_size_read(dir);
+
+	de_buf = di->id2.i_data.id_data;
+	limit = de_buf + i_size_read(dir);
+	rec_len = OCFS2_DIR_REC_LEN(namelen);
+
+	while (de_buf < limit) {
+		de = (struct ocfs2_dir_entry *)de_buf;
+
+		if (!ocfs2_check_dir_entry(dir, de, di_bh, offset)) {
+			ret = -ENOENT;
+			goto out;
+		}
+		if (ocfs2_match(namelen, name, de)) {
+			ret = -EEXIST;
+			goto out;
+		}
+		/*
+		 * No need to check for a trailing dirent record here as
+		 * they're not used for inline dirs.
+		 */
+
+		if (ocfs2_dirent_would_fit(de, rec_len)) {
+			/* Ok, we found a spot. Return this bh and let
+			 * the caller actually fill it in. */
+			*ret_de_bh = di_bh;
+			get_bh(*ret_de_bh);
+			ret = 0;
+			goto out;
+		}
+
+		last_de = de;
+		de_buf += le16_to_cpu(de->rec_len);
+		offset += le16_to_cpu(de->rec_len);
+	}
+
+	/*
+	 * We're going to require expansion of the directory - figure
+	 * out how many blocks we'll need so that a place for the
+	 * dirent can be found.
+	 */
+	*blocks_wanted = 1;
+	new_rec_len = le16_to_cpu(last_de->rec_len) + free_space;
+	if (new_rec_len < (rec_len + OCFS2_DIR_REC_LEN(last_de->name_len)))
+		*blocks_wanted = 2;
+
+	ret = -ENOSPC;
+out:
+	return ret;
+}
+
+static int ocfs2_find_dir_space_el(struct inode *dir, const char *name,
+				   int namelen, struct buffer_head **ret_de_bh)
+{
+	unsigned long offset;
+	struct buffer_head *bh = NULL;
+	unsigned short rec_len;
+	struct ocfs2_dir_entry *de;
+	struct super_block *sb = dir->i_sb;
+	int status;
+	int blocksize = dir->i_sb->s_blocksize;
+
+	status = ocfs2_read_dir_block(dir, 0, &bh, 0);
+	if (status)
+		goto bail;
+
+	rec_len = OCFS2_DIR_REC_LEN(namelen);
+	offset = 0;
+	de = (struct ocfs2_dir_entry *) bh->b_data;
+	while (1) {
+		if ((char *)de >= sb->s_blocksize + bh->b_data) {
+			brelse(bh);
+			bh = NULL;
+
+			if (i_size_read(dir) <= offset) {
+				/*
+				 * Caller will have to expand this
+				 * directory.
+				 */
+				status = -ENOSPC;
+				goto bail;
+			}
+			status = ocfs2_read_dir_block(dir,
+					     offset >> sb->s_blocksize_bits,
+					     &bh, 0);
+			if (status)
+				goto bail;
+
+			/* move to next block */
+			de = (struct ocfs2_dir_entry *) bh->b_data;
+		}
+		if (!ocfs2_check_dir_entry(dir, de, bh, offset)) {
+			status = -ENOENT;
+			goto bail;
+		}
+		if (ocfs2_match(namelen, name, de)) {
+			status = -EEXIST;
+			goto bail;
+		}
+
+		if (ocfs2_skip_dir_trailer(dir, de, offset % blocksize,
+					   blocksize))
+			goto next;
+
+		if (ocfs2_dirent_would_fit(de, rec_len)) {
+			/* Ok, we found a spot. Return this bh and let
+			 * the caller actually fill it in. */
+			*ret_de_bh = bh;
+			get_bh(*ret_de_bh);
+			status = 0;
+			goto bail;
+		}
+next:
+		offset += le16_to_cpu(de->rec_len);
+		de = (struct ocfs2_dir_entry *)((char *) de + le16_to_cpu(de->rec_len));
+	}
+
+bail:
+	brelse(bh);
+	if (status)
+		mlog_errno(status);
+
+	return status;
+}
+
+static int dx_leaf_sort_cmp(const void *a, const void *b)
+{
+	const struct ocfs2_dx_entry *entry1 = a;
+	const struct ocfs2_dx_entry *entry2 = b;
+	u32 major_hash1 = le32_to_cpu(entry1->dx_major_hash);
+	u32 major_hash2 = le32_to_cpu(entry2->dx_major_hash);
+	u32 minor_hash1 = le32_to_cpu(entry1->dx_minor_hash);
+	u32 minor_hash2 = le32_to_cpu(entry2->dx_minor_hash);
+
+	if (major_hash1 > major_hash2)
+		return 1;
+	if (major_hash1 < major_hash2)
+		return -1;
+
+	/*
+	 * It is not strictly necessary to sort by minor
+	 */
+	if (minor_hash1 > minor_hash2)
+		return 1;
+	if (minor_hash1 < minor_hash2)
+		return -1;
+	return 0;
+}
+
+static void dx_leaf_sort_swap(void *a, void *b, int size)
+{
+	struct ocfs2_dx_entry *entry1 = a;
+	struct ocfs2_dx_entry *entry2 = b;
+	struct ocfs2_dx_entry tmp;
+
+	BUG_ON(size != sizeof(*entry1));
+
+	tmp = *entry1;
+	*entry1 = *entry2;
+	*entry2 = tmp;
+}
+
+static int ocfs2_dx_leaf_same_major(struct ocfs2_dx_leaf *dx_leaf)
+{
+	struct ocfs2_dx_entry_list *dl_list = &dx_leaf->dl_list;
+	int i, num = le16_to_cpu(dl_list->de_num_used);
+
+	for (i = 0; i < (num - 1); i++) {
+		if (le32_to_cpu(dl_list->de_entries[i].dx_major_hash) !=
+		    le32_to_cpu(dl_list->de_entries[i + 1].dx_major_hash))
+			return 0;
+	}
+
+	return 1;
+}
+
+/*
+ * Find the optimal value to split this leaf on. This expects the leaf
+ * entries to be in sorted order.
+ *
+ * leaf_cpos is the cpos of the leaf we're splitting. insert_hash is
+ * the hash we want to insert.
+ *
+ * This function is only concerned with the major hash - that which
+ * determines which cluster an item belongs to.
+ */
+static int ocfs2_dx_dir_find_leaf_split(struct ocfs2_dx_leaf *dx_leaf,
+					u32 leaf_cpos, u32 insert_hash,
+					u32 *split_hash)
+{
+	struct ocfs2_dx_entry_list *dl_list = &dx_leaf->dl_list;
+	int i, num_used = le16_to_cpu(dl_list->de_num_used);
+	int allsame;
+
+	/*
+	 * There's a couple rare, but nasty corner cases we have to
+	 * check for here. All of them involve a leaf where all value
+	 * have the same hash, which is what we look for first.
+	 *
+	 * Most of the time, all of the above is false, and we simply
+	 * pick the median value for a split.
+	 */
+	allsame = ocfs2_dx_leaf_same_major(dx_leaf);
+	if (allsame) {
+		u32 val = le32_to_cpu(dl_list->de_entries[0].dx_major_hash);
+
+		if (val == insert_hash) {
+			/*
+			 * No matter where we would choose to split,
+			 * the new entry would want to occupy the same
+			 * block as these. Since there's no space left
+			 * in their existing block, we know there
+			 * won't be space after the split.
+			 */
+			return -ENOSPC;
+		}
+
+		if (val == leaf_cpos) {
+			/*
+			 * Because val is the same as leaf_cpos (which
+			 * is the smallest value this leaf can have),
+			 * yet is not equal to insert_hash, then we
+			 * know that insert_hash *must* be larger than
+			 * val (and leaf_cpos). At least cpos+1 in value.
+			 *
+			 * We also know then, that there cannot be an
+			 * adjacent extent (otherwise we'd be looking
+			 * at it). Choosing this value gives us a
+			 * chance to get some contiguousness.
+			 */
+			*split_hash = leaf_cpos + 1;
+			return 0;
+		}
+
+		if (val > insert_hash) {
+			/*
+			 * val can not be the same as insert hash, and
+			 * also must be larger than leaf_cpos. Also,
+			 * we know that there can't be a leaf between
+			 * cpos and val, otherwise the entries with
+			 * hash 'val' would be there.
+			 */
+			*split_hash = val;
+			return 0;
+		}
+
+		*split_hash = insert_hash;
+		return 0;
+	}
+
+	/*
+	 * Since the records are sorted and the checks above
+	 * guaranteed that not all records in this block are the same,
+	 * we simple travel forward, from the median, and pick the 1st
+	 * record whose value is larger than leaf_cpos.
+	 */
+	for (i = (num_used / 2); i < num_used; i++)
+		if (le32_to_cpu(dl_list->de_entries[i].dx_major_hash) >
+		    leaf_cpos)
+			break;
+
+	BUG_ON(i == num_used); /* Should be impossible */
+	*split_hash = le32_to_cpu(dl_list->de_entries[i].dx_major_hash);
+	return 0;
+}
+
+/*
+ * Transfer all entries in orig_dx_leaves whose major hash is equal to or
+ * larger than split_hash into new_dx_leaves. We use a temporary
+ * buffer (tmp_dx_leaf) to make the changes to the original leaf blocks.
+ *
+ * Since the block offset inside a leaf (cluster) is a constant mask
+ * of minor_hash, we can optimize - an item at block offset X within
+ * the original cluster, will be at offset X within the new cluster.
+ */
+static void ocfs2_dx_dir_transfer_leaf(struct inode *dir, u32 split_hash,
+				       handle_t *handle,
+				       struct ocfs2_dx_leaf *tmp_dx_leaf,
+				       struct buffer_head **orig_dx_leaves,
+				       struct buffer_head **new_dx_leaves,
+				       int num_dx_leaves)
+{
+	int i, j, num_used;
+	u32 major_hash;
+	struct ocfs2_dx_leaf *orig_dx_leaf, *new_dx_leaf;
+	struct ocfs2_dx_entry_list *orig_list, *new_list, *tmp_list;
+	struct ocfs2_dx_entry *dx_entry;
+
+	tmp_list = &tmp_dx_leaf->dl_list;
+
+	for (i = 0; i < num_dx_leaves; i++) {
+		orig_dx_leaf = (struct ocfs2_dx_leaf *) orig_dx_leaves[i]->b_data;
+		orig_list = &orig_dx_leaf->dl_list;
+		new_dx_leaf = (struct ocfs2_dx_leaf *) new_dx_leaves[i]->b_data;
+		new_list = &new_dx_leaf->dl_list;
+
+		num_used = le16_to_cpu(orig_list->de_num_used);
+
+		memcpy(tmp_dx_leaf, orig_dx_leaf, dir->i_sb->s_blocksize);
+		tmp_list->de_num_used = cpu_to_le16(0);
+		memset(&tmp_list->de_entries, 0, sizeof(*dx_entry)*num_used);
+
+		for (j = 0; j < num_used; j++) {
+			dx_entry = &orig_list->de_entries[j];
+			major_hash = le32_to_cpu(dx_entry->dx_major_hash);
+			if (major_hash >= split_hash)
+				ocfs2_dx_dir_leaf_insert_tail(new_dx_leaf,
+							      dx_entry);
+			else
+				ocfs2_dx_dir_leaf_insert_tail(tmp_dx_leaf,
+							      dx_entry);
+		}
+		memcpy(orig_dx_leaf, tmp_dx_leaf, dir->i_sb->s_blocksize);
+
+		ocfs2_journal_dirty(handle, orig_dx_leaves[i]);
+		ocfs2_journal_dirty(handle, new_dx_leaves[i]);
+	}
+}
+
+static int ocfs2_dx_dir_rebalance_credits(struct ocfs2_super *osb,
+					  struct ocfs2_dx_root_block *dx_root)
+{
+	int credits = ocfs2_clusters_to_blocks(osb->sb, 2);
+
+	credits += ocfs2_calc_extend_credits(osb->sb, &dx_root->dr_list);
+	credits += ocfs2_quota_trans_credits(osb->sb);
+	return credits;
+}
+
+/*
+ * Find the median value in dx_leaf_bh and allocate a new leaf to move
+ * half our entries into.
+ */
+static int ocfs2_dx_dir_rebalance(struct ocfs2_super *osb, struct inode *dir,
+				  struct buffer_head *dx_root_bh,
+				  struct buffer_head *dx_leaf_bh,
+				  struct ocfs2_dx_hinfo *hinfo, u32 leaf_cpos,
+				  u64 leaf_blkno)
+{
+	struct ocfs2_dx_leaf *dx_leaf = (struct ocfs2_dx_leaf *)dx_leaf_bh->b_data;
+	int credits, ret, i, num_used, did_quota = 0;
+	u32 cpos, split_hash, insert_hash = hinfo->major_hash;
+	u64 orig_leaves_start;
+	int num_dx_leaves;
+	struct buffer_head **orig_dx_leaves = NULL;
+	struct buffer_head **new_dx_leaves = NULL;
+	struct ocfs2_alloc_context *data_ac = NULL, *meta_ac = NULL;
+	struct ocfs2_extent_tree et;
+	handle_t *handle = NULL;
+	struct ocfs2_dx_root_block *dx_root;
+	struct ocfs2_dx_leaf *tmp_dx_leaf = NULL;
+
+	trace_ocfs2_dx_dir_rebalance((unsigned long long)OCFS2_I(dir)->ip_blkno,
+				     (unsigned long long)leaf_blkno,
+				     insert_hash);
+
+	ocfs2_init_dx_root_extent_tree(&et, INODE_CACHE(dir), dx_root_bh);
+
+	dx_root = (struct ocfs2_dx_root_block *)dx_root_bh->b_data;
+	/*
+	 * XXX: This is a rather large limit. We should use a more
+	 * realistic value.
+	 */
+	if (le32_to_cpu(dx_root->dr_clusters) == UINT_MAX)
+		return -ENOSPC;
+
+	num_used = le16_to_cpu(dx_leaf->dl_list.de_num_used);
+	if (num_used < le16_to_cpu(dx_leaf->dl_list.de_count)) {
+		mlog(ML_ERROR, "DX Dir: %llu, Asked to rebalance empty leaf: "
+		     "%llu, %d\n", (unsigned long long)OCFS2_I(dir)->ip_blkno,
+		     (unsigned long long)leaf_blkno, num_used);
+		ret = -EIO;
+		goto out;
+	}
+
+	orig_dx_leaves = ocfs2_dx_dir_kmalloc_leaves(osb->sb, &num_dx_leaves);
+	if (!orig_dx_leaves) {
+		ret = -ENOMEM;
+		mlog_errno(ret);
+		goto out;
+	}
+
+	new_dx_leaves = ocfs2_dx_dir_kmalloc_leaves(osb->sb, NULL);
+	if (!new_dx_leaves) {
+		ret = -ENOMEM;
+		mlog_errno(ret);
+		goto out;
+	}
+
+	ret = ocfs2_lock_allocators(dir, &et, 1, 0, &data_ac, &meta_ac);
+	if (ret) {
+		if (ret != -ENOSPC)
+			mlog_errno(ret);
+		goto out;
+	}
+
+	credits = ocfs2_dx_dir_rebalance_credits(osb, dx_root);
+	handle = ocfs2_start_trans(osb, credits);
+	if (IS_ERR(handle)) {
+		ret = PTR_ERR(handle);
+		handle = NULL;
+		mlog_errno(ret);
+		goto out;
+	}
+
+	ret = dquot_alloc_space_nodirty(dir,
+				       ocfs2_clusters_to_bytes(dir->i_sb, 1));
+	if (ret)
+		goto out_commit;
+	did_quota = 1;
+
+	ret = ocfs2_journal_access_dl(handle, INODE_CACHE(dir), dx_leaf_bh,
+				      OCFS2_JOURNAL_ACCESS_WRITE);
+	if (ret) {
+		mlog_errno(ret);
+		goto out_commit;
+	}
+
+	/*
+	 * This block is changing anyway, so we can sort it in place.
+	 */
+	sort(dx_leaf->dl_list.de_entries, num_used,
+	     sizeof(struct ocfs2_dx_entry), dx_leaf_sort_cmp,
+	     dx_leaf_sort_swap);
+
+	ocfs2_journal_dirty(handle, dx_leaf_bh);
+
+	ret = ocfs2_dx_dir_find_leaf_split(dx_leaf, leaf_cpos, insert_hash,
+					   &split_hash);
+	if (ret) {
+		mlog_errno(ret);
+		goto  out_commit;
+	}
+
+	trace_ocfs2_dx_dir_rebalance_split(leaf_cpos, split_hash, insert_hash);
+
+	/*
+	 * We have to carefully order operations here. There are items
+	 * which want to be in the new cluster before insert, but in
+	 * order to put those items in the new cluster, we alter the
+	 * old cluster. A failure to insert gets nasty.
+	 *
+	 * So, start by reserving writes to the old
+	 * cluster. ocfs2_dx_dir_new_cluster will reserve writes on
+	 * the new cluster for us, before inserting it. The insert
+	 * won't happen if there's an error before that. Once the
+	 * insert is done then, we can transfer from one leaf into the
+	 * other without fear of hitting any error.
+	 */
+
+	/*
+	 * The leaf transfer wants some scratch space so that we don't
+	 * wind up doing a bunch of expensive memmove().
+	 */
+	tmp_dx_leaf = kmalloc(osb->sb->s_blocksize, GFP_NOFS);
+	if (!tmp_dx_leaf) {
+		ret = -ENOMEM;
+		mlog_errno(ret);
+		goto out_commit;
+	}
+
+	orig_leaves_start = ocfs2_block_to_cluster_start(dir->i_sb, leaf_blkno);
+	ret = ocfs2_read_dx_leaves(dir, orig_leaves_start, num_dx_leaves,
+				   orig_dx_leaves);
+	if (ret) {
+		mlog_errno(ret);
+		goto out_commit;
+	}
+
+	cpos = split_hash;
+	ret = ocfs2_dx_dir_new_cluster(dir, &et, cpos, handle,
+				       data_ac, meta_ac, new_dx_leaves,
+				       num_dx_leaves);
+	if (ret) {
+		mlog_errno(ret);
+		goto out_commit;
+	}
+
+	for (i = 0; i < num_dx_leaves; i++) {
+		ret = ocfs2_journal_access_dl(handle, INODE_CACHE(dir),
+					      orig_dx_leaves[i],
+					      OCFS2_JOURNAL_ACCESS_WRITE);
+		if (ret) {
+			mlog_errno(ret);
+			goto out_commit;
+		}
+
+		ret = ocfs2_journal_access_dl(handle, INODE_CACHE(dir),
+					      new_dx_leaves[i],
+					      OCFS2_JOURNAL_ACCESS_WRITE);
+		if (ret) {
+			mlog_errno(ret);
+			goto out_commit;
+		}
+	}
+
+	ocfs2_dx_dir_transfer_leaf(dir, split_hash, handle, tmp_dx_leaf,
+				   orig_dx_leaves, new_dx_leaves, num_dx_leaves);
+
+out_commit:
+	if (ret < 0 && did_quota)
+		dquot_free_space_nodirty(dir,
+				ocfs2_clusters_to_bytes(dir->i_sb, 1));
+
+	ocfs2_update_inode_fsync_trans(handle, dir, 1);
+	ocfs2_commit_trans(osb, handle);
+
+out:
+	if (orig_dx_leaves || new_dx_leaves) {
+		for (i = 0; i < num_dx_leaves; i++) {
+			if (orig_dx_leaves)
+				brelse(orig_dx_leaves[i]);
+			if (new_dx_leaves)
+				brelse(new_dx_leaves[i]);
+		}
+		kfree(orig_dx_leaves);
+		kfree(new_dx_leaves);
+	}
+
+	if (meta_ac)
+		ocfs2_free_alloc_context(meta_ac);
+	if (data_ac)
+		ocfs2_free_alloc_context(data_ac);
+
+	kfree(tmp_dx_leaf);
+	return ret;
+}
+
+static int ocfs2_find_dir_space_dx(struct ocfs2_super *osb, struct inode *dir,
+				   struct buffer_head *di_bh,
+				   struct buffer_head *dx_root_bh,
+				   const char *name, int namelen,
+				   struct ocfs2_dir_lookup_result *lookup)
+{
+	int ret, rebalanced = 0;
+	struct ocfs2_dx_root_block *dx_root;
+	struct buffer_head *dx_leaf_bh = NULL;
+	struct ocfs2_dx_leaf *dx_leaf;
+	u64 blkno;
+	u32 leaf_cpos;
+
+	dx_root = (struct ocfs2_dx_root_block *)dx_root_bh->b_data;
+
+restart_search:
+	ret = ocfs2_dx_dir_lookup(dir, &dx_root->dr_list, &lookup->dl_hinfo,
+				  &leaf_cpos, &blkno);
+	if (ret) {
+		mlog_errno(ret);
+		goto out;
+	}
+
+	ret = ocfs2_read_dx_leaf(dir, blkno, &dx_leaf_bh);
+	if (ret) {
+		mlog_errno(ret);
+		goto out;
+	}
+
+	dx_leaf = (struct ocfs2_dx_leaf *)dx_leaf_bh->b_data;
+
+	if (le16_to_cpu(dx_leaf->dl_list.de_num_used) >=
+	    le16_to_cpu(dx_leaf->dl_list.de_count)) {
+		if (rebalanced) {
+			/*
+			 * Rebalancing should have provided us with
+			 * space in an appropriate leaf.
+			 *
+			 * XXX: Is this an abnormal condition then?
+			 * Should we print a message here?
+			 */
+			ret = -ENOSPC;
+			goto out;
+		}
+
+		ret = ocfs2_dx_dir_rebalance(osb, dir, dx_root_bh, dx_leaf_bh,
+					     &lookup->dl_hinfo, leaf_cpos,
+					     blkno);
+		if (ret) {
+			if (ret != -ENOSPC)
+				mlog_errno(ret);
+			goto out;
+		}
+
+		/*
+		 * Restart the lookup. The rebalance might have
+		 * changed which block our item fits into. Mark our
+		 * progress, so we only execute this once.
+		 */
+		brelse(dx_leaf_bh);
+		dx_leaf_bh = NULL;
+		rebalanced = 1;
+		goto restart_search;
+	}
+
+	lookup->dl_dx_leaf_bh = dx_leaf_bh;
+	dx_leaf_bh = NULL;
+
+out:
+	brelse(dx_leaf_bh);
+	return ret;
+}
+
+static int ocfs2_search_dx_free_list(struct inode *dir,
+				     struct buffer_head *dx_root_bh,
+				     int namelen,
+				     struct ocfs2_dir_lookup_result *lookup)
+{
+	int ret = -ENOSPC;
+	struct buffer_head *leaf_bh = NULL, *prev_leaf_bh = NULL;
+	struct ocfs2_dir_block_trailer *db;
+	u64 next_block;
+	int rec_len = OCFS2_DIR_REC_LEN(namelen);
+	struct ocfs2_dx_root_block *dx_root;
+
+	dx_root = (struct ocfs2_dx_root_block *)dx_root_bh->b_data;
+	next_block = le64_to_cpu(dx_root->dr_free_blk);
+
+	while (next_block) {
+		brelse(prev_leaf_bh);
+		prev_leaf_bh = leaf_bh;
+		leaf_bh = NULL;
+
+		ret = ocfs2_read_dir_block_direct(dir, next_block, &leaf_bh);
+		if (ret) {
+			mlog_errno(ret);
+			goto out;
+		}
+
+		db = ocfs2_trailer_from_bh(leaf_bh, dir->i_sb);
+		if (rec_len <= le16_to_cpu(db->db_free_rec_len)) {
+			lookup->dl_leaf_bh = leaf_bh;
+			lookup->dl_prev_leaf_bh = prev_leaf_bh;
+			leaf_bh = NULL;
+			prev_leaf_bh = NULL;
+			break;
+		}
+
+		next_block = le64_to_cpu(db->db_free_next);
+	}
+
+	if (!next_block)
+		ret = -ENOSPC;
+
+out:
+
+	brelse(leaf_bh);
+	brelse(prev_leaf_bh);
+	return ret;
+}
+
+static int ocfs2_expand_inline_dx_root(struct inode *dir,
+				       struct buffer_head *dx_root_bh)
+{
+	int ret, num_dx_leaves, i, j, did_quota = 0;
+	struct buffer_head **dx_leaves = NULL;
+	struct ocfs2_extent_tree et;
+	u64 insert_blkno;
+	struct ocfs2_alloc_context *data_ac = NULL;
+	struct ocfs2_super *osb = OCFS2_SB(dir->i_sb);
+	handle_t *handle = NULL;
+	struct ocfs2_dx_root_block *dx_root;
+	struct ocfs2_dx_entry_list *entry_list;
+	struct ocfs2_dx_entry *dx_entry;
+	struct ocfs2_dx_leaf *target_leaf;
+
+	ret = ocfs2_reserve_clusters(osb, 1, &data_ac);
+	if (ret) {
+		mlog_errno(ret);
+		goto out;
+	}
+
+	dx_leaves = ocfs2_dx_dir_kmalloc_leaves(osb->sb, &num_dx_leaves);
+	if (!dx_leaves) {
+		ret = -ENOMEM;
+		mlog_errno(ret);
+		goto out;
+	}
+
+	handle = ocfs2_start_trans(osb, ocfs2_calc_dxi_expand_credits(osb->sb));
+	if (IS_ERR(handle)) {
+		ret = PTR_ERR(handle);
+		mlog_errno(ret);
+		goto out;
+	}
+
+	ret = dquot_alloc_space_nodirty(dir,
+				       ocfs2_clusters_to_bytes(osb->sb, 1));
+	if (ret)
+		goto out_commit;
+	did_quota = 1;
+
+	/*
+	 * We do this up front, before the allocation, so that a
+	 * failure to add the dx_root_bh to the journal won't result
+	 * us losing clusters.
+	 */
+	ret = ocfs2_journal_access_dr(handle, INODE_CACHE(dir), dx_root_bh,
+				      OCFS2_JOURNAL_ACCESS_WRITE);
+	if (ret) {
+		mlog_errno(ret);
+		goto out_commit;
+	}
+
+	ret = __ocfs2_dx_dir_new_cluster(dir, 0, handle, data_ac, dx_leaves,
+					 num_dx_leaves, &insert_blkno);
+	if (ret) {
+		mlog_errno(ret);
+		goto out_commit;
+	}
+
+	/*
+	 * Transfer the entries from our dx_root into the appropriate
+	 * block
+	 */
+	dx_root = (struct ocfs2_dx_root_block *) dx_root_bh->b_data;
+	entry_list = &dx_root->dr_entries;
+
+	for (i = 0; i < le16_to_cpu(entry_list->de_num_used); i++) {
+		dx_entry = &entry_list->de_entries[i];
+
+		j = __ocfs2_dx_dir_hash_idx(osb,
+					    le32_to_cpu(dx_entry->dx_minor_hash));
+		target_leaf = (struct ocfs2_dx_leaf *)dx_leaves[j]->b_data;
+
+		ocfs2_dx_dir_leaf_insert_tail(target_leaf, dx_entry);
+
+		/* Each leaf has been passed to the journal already
+		 * via __ocfs2_dx_dir_new_cluster() */
+	}
+
+	dx_root->dr_flags &= ~OCFS2_DX_FLAG_INLINE;
+	memset(&dx_root->dr_list, 0, osb->sb->s_blocksize -
+	       offsetof(struct ocfs2_dx_root_block, dr_list));
+	dx_root->dr_list.l_count =
+		cpu_to_le16(ocfs2_extent_recs_per_dx_root(osb->sb));
+
+	/* This should never fail considering we start with an empty
+	 * dx_root. */
+	ocfs2_init_dx_root_extent_tree(&et, INODE_CACHE(dir), dx_root_bh);
+	ret = ocfs2_insert_extent(handle, &et, 0, insert_blkno, 1, 0, NULL);
+	if (ret)
+		mlog_errno(ret);
+	did_quota = 0;
+
+	ocfs2_update_inode_fsync_trans(handle, dir, 1);
+	ocfs2_journal_dirty(handle, dx_root_bh);
+
+out_commit:
+	if (ret < 0 && did_quota)
+		dquot_free_space_nodirty(dir,
+					  ocfs2_clusters_to_bytes(dir->i_sb, 1));
+
+	ocfs2_commit_trans(osb, handle);
+
+out:
+	if (data_ac)
+		ocfs2_free_alloc_context(data_ac);
+
+	if (dx_leaves) {
+		for (i = 0; i < num_dx_leaves; i++)
+			brelse(dx_leaves[i]);
+		kfree(dx_leaves);
+	}
+	return ret;
+}
+
+static int ocfs2_inline_dx_has_space(struct buffer_head *dx_root_bh)
+{
+	struct ocfs2_dx_root_block *dx_root;
+	struct ocfs2_dx_entry_list *entry_list;
+
+	dx_root = (struct ocfs2_dx_root_block *) dx_root_bh->b_data;
+	entry_list = &dx_root->dr_entries;
+
+	if (le16_to_cpu(entry_list->de_num_used) >=
+	    le16_to_cpu(entry_list->de_count))
+		return -ENOSPC;
+
+	return 0;
+}
+
+static int ocfs2_prepare_dx_dir_for_insert(struct inode *dir,
+					   struct buffer_head *di_bh,
+					   const char *name,
+					   int namelen,
+					   struct ocfs2_dir_lookup_result *lookup)
+{
+	int ret, free_dx_root = 1;
+	struct ocfs2_super *osb = OCFS2_SB(dir->i_sb);
+	struct buffer_head *dx_root_bh = NULL;
+	struct buffer_head *leaf_bh = NULL;
+	struct ocfs2_dinode *di = (struct ocfs2_dinode *)di_bh->b_data;
+	struct ocfs2_dx_root_block *dx_root;
+
+	ret = ocfs2_read_dx_root(dir, di, &dx_root_bh);
+	if (ret) {
+		mlog_errno(ret);
+		goto out;
+	}
+
+	dx_root = (struct ocfs2_dx_root_block *)dx_root_bh->b_data;
+	if (le32_to_cpu(dx_root->dr_num_entries) == OCFS2_DX_ENTRIES_MAX) {
+		ret = -ENOSPC;
+		mlog_errno(ret);
+		goto out;
+	}
+
+	if (ocfs2_dx_root_inline(dx_root)) {
+		ret = ocfs2_inline_dx_has_space(dx_root_bh);
+
+		if (ret == 0)
+			goto search_el;
+
+		/*
+		 * We ran out of room in the root block. Expand it to
+		 * an extent, then allow ocfs2_find_dir_space_dx to do
+		 * the rest.
+		 */
+		ret = ocfs2_expand_inline_dx_root(dir, dx_root_bh);
+		if (ret) {
+			mlog_errno(ret);
+			goto out;
+		}
+	}
+
+	/*
+	 * Insert preparation for an indexed directory is split into two
+	 * steps. The call to find_dir_space_dx reserves room in the index for
+	 * an additional item. If we run out of space there, it's a real error
+	 * we can't continue on.
+	 */
+	ret = ocfs2_find_dir_space_dx(osb, dir, di_bh, dx_root_bh, name,
+				      namelen, lookup);
+	if (ret) {
+		mlog_errno(ret);
+		goto out;
+	}
+
+search_el:
+	/*
+	 * Next, we need to find space in the unindexed tree. This call
+	 * searches using the free space linked list. If the unindexed tree
+	 * lacks sufficient space, we'll expand it below. The expansion code
+	 * is smart enough to add any new blocks to the free space list.
+	 */
+	ret = ocfs2_search_dx_free_list(dir, dx_root_bh, namelen, lookup);
+	if (ret && ret != -ENOSPC) {
+		mlog_errno(ret);
+		goto out;
+	}
+
+	/* Do this up here - ocfs2_extend_dir might need the dx_root */
+	lookup->dl_dx_root_bh = dx_root_bh;
+	free_dx_root = 0;
+
+	if (ret == -ENOSPC) {
+		ret = ocfs2_extend_dir(osb, dir, di_bh, 1, lookup, &leaf_bh);
+
+		if (ret) {
+			mlog_errno(ret);
+			goto out;
+		}
+
+		/*
+		 * We make the assumption here that new leaf blocks are added
+		 * to the front of our free list.
+		 */
+		lookup->dl_prev_leaf_bh = NULL;
+		lookup->dl_leaf_bh = leaf_bh;
+	}
+
+out:
+	if (free_dx_root)
+		brelse(dx_root_bh);
+	return ret;
+}
+
+/*
+ * Get a directory ready for insert. Any directory allocation required
+ * happens here. Success returns zero, and enough context in the dir
+ * lookup result that ocfs2_add_entry() will be able complete the task
+ * with minimal performance impact.
+ */
+int ocfs2_prepare_dir_for_insert(struct ocfs2_super *osb,
+				 struct inode *dir,
+				 struct buffer_head *parent_fe_bh,
+				 const char *name,
+				 int namelen,
+				 struct ocfs2_dir_lookup_result *lookup)
+{
+	int ret;
+	unsigned int blocks_wanted = 1;
+	struct buffer_head *bh = NULL;
+
+	trace_ocfs2_prepare_dir_for_insert(
+		(unsigned long long)OCFS2_I(dir)->ip_blkno, namelen);
+
+	if (!namelen) {
+		ret = -EINVAL;
+		mlog_errno(ret);
+		goto out;
+	}
+
+	/*
+	 * Do this up front to reduce confusion.
+	 *
+	 * The directory might start inline, then be turned into an
+	 * indexed one, in which case we'd need to hash deep inside
+	 * ocfs2_find_dir_space_id(). Since
+	 * ocfs2_prepare_dx_dir_for_insert() also needs this hash
+	 * done, there seems no point in spreading out the calls. We
+	 * can optimize away the case where the file system doesn't
+	 * support indexing.
+	 */
+	if (ocfs2_supports_indexed_dirs(osb))
+		ocfs2_dx_dir_name_hash(dir, name, namelen, &lookup->dl_hinfo);
+
+	if (ocfs2_dir_indexed(dir)) {
+		ret = ocfs2_prepare_dx_dir_for_insert(dir, parent_fe_bh,
+						      name, namelen, lookup);
+		if (ret)
+			mlog_errno(ret);
+		goto out;
+	}
+
+	if (OCFS2_I(dir)->ip_dyn_features & OCFS2_INLINE_DATA_FL) {
+		ret = ocfs2_find_dir_space_id(dir, parent_fe_bh, name,
+					      namelen, &bh, &blocks_wanted);
+	} else
+		ret = ocfs2_find_dir_space_el(dir, name, namelen, &bh);
+
+	if (ret && ret != -ENOSPC) {
+		mlog_errno(ret);
+		goto out;
+	}
+
+	if (ret == -ENOSPC) {
+		/*
+		 * We have to expand the directory to add this name.
+		 */
+		BUG_ON(bh);
+
+		ret = ocfs2_extend_dir(osb, dir, parent_fe_bh, blocks_wanted,
+				       lookup, &bh);
+		if (ret) {
+			if (ret != -ENOSPC)
+				mlog_errno(ret);
+			goto out;
+		}
+
+		BUG_ON(!bh);
+	}
+
+	lookup->dl_leaf_bh = bh;
+	bh = NULL;
+out:
+	brelse(bh);
+	return ret;
+}
+
+static int ocfs2_dx_dir_remove_index(struct inode *dir,
+				     struct buffer_head *di_bh,
+				     struct buffer_head *dx_root_bh)
+{
+	int ret;
+	struct ocfs2_super *osb = OCFS2_SB(dir->i_sb);
+	struct ocfs2_dinode *di = (struct ocfs2_dinode *)di_bh->b_data;
+	struct ocfs2_dx_root_block *dx_root;
+	struct inode *dx_alloc_inode = NULL;
+	struct buffer_head *dx_alloc_bh = NULL;
+	handle_t *handle;
+	u64 blk;
+	u16 bit;
+	u64 bg_blkno;
+
+	dx_root = (struct ocfs2_dx_root_block *) dx_root_bh->b_data;
+
+	dx_alloc_inode = ocfs2_get_system_file_inode(osb,
+					EXTENT_ALLOC_SYSTEM_INODE,
+					le16_to_cpu(dx_root->dr_suballoc_slot));
+	if (!dx_alloc_inode) {
+		ret = -ENOMEM;
+		mlog_errno(ret);
+		goto out;
+	}
+	mutex_lock(&dx_alloc_inode->i_mutex);
+
+	ret = ocfs2_inode_lock(dx_alloc_inode, &dx_alloc_bh, 1);
+	if (ret) {
+		mlog_errno(ret);
+		goto out_mutex;
+	}
+
+	handle = ocfs2_start_trans(osb, OCFS2_DX_ROOT_REMOVE_CREDITS);
+	if (IS_ERR(handle)) {
+		ret = PTR_ERR(handle);
+		mlog_errno(ret);
+		goto out_unlock;
+	}
+
+	ret = ocfs2_journal_access_di(handle, INODE_CACHE(dir), di_bh,
+				      OCFS2_JOURNAL_ACCESS_WRITE);
+	if (ret) {
+		mlog_errno(ret);
+		goto out_commit;
+	}
+
+	spin_lock(&OCFS2_I(dir)->ip_lock);
+	OCFS2_I(dir)->ip_dyn_features &= ~OCFS2_INDEXED_DIR_FL;
+	di->i_dyn_features = cpu_to_le16(OCFS2_I(dir)->ip_dyn_features);
+	spin_unlock(&OCFS2_I(dir)->ip_lock);
+	di->i_dx_root = cpu_to_le64(0ULL);
+	ocfs2_update_inode_fsync_trans(handle, dir, 1);
+
+	ocfs2_journal_dirty(handle, di_bh);
+
+	blk = le64_to_cpu(dx_root->dr_blkno);
+	bit = le16_to_cpu(dx_root->dr_suballoc_bit);
+	if (dx_root->dr_suballoc_loc)
+		bg_blkno = le64_to_cpu(dx_root->dr_suballoc_loc);
+	else
+		bg_blkno = ocfs2_which_suballoc_group(blk, bit);
+	ret = ocfs2_free_suballoc_bits(handle, dx_alloc_inode, dx_alloc_bh,
+				       bit, bg_blkno, 1);
+	if (ret)
+		mlog_errno(ret);
+
+out_commit:
+	ocfs2_commit_trans(osb, handle);
+
+out_unlock:
+	ocfs2_inode_unlock(dx_alloc_inode, 1);
+
+out_mutex:
+	mutex_unlock(&dx_alloc_inode->i_mutex);
+	brelse(dx_alloc_bh);
+out:
+	iput(dx_alloc_inode);
+	return ret;
+}
+
+int ocfs2_dx_dir_truncate(struct inode *dir, struct buffer_head *di_bh)
+{
+	int ret;
+	unsigned int uninitialized_var(clen);
+	u32 major_hash = UINT_MAX, p_cpos, uninitialized_var(cpos);
+	u64 uninitialized_var(blkno);
+	struct ocfs2_super *osb = OCFS2_SB(dir->i_sb);
+	struct buffer_head *dx_root_bh = NULL;
+	struct ocfs2_dx_root_block *dx_root;
+	struct ocfs2_dinode *di = (struct ocfs2_dinode *)di_bh->b_data;
+	struct ocfs2_cached_dealloc_ctxt dealloc;
+	struct ocfs2_extent_tree et;
+
+	ocfs2_init_dealloc_ctxt(&dealloc);
+
+	if (!ocfs2_dir_indexed(dir))
+		return 0;
+
+	ret = ocfs2_read_dx_root(dir, di, &dx_root_bh);
+	if (ret) {
+		mlog_errno(ret);
+		goto out;
+	}
+	dx_root = (struct ocfs2_dx_root_block *)dx_root_bh->b_data;
+
+	if (ocfs2_dx_root_inline(dx_root))
+		goto remove_index;
+
+	ocfs2_init_dx_root_extent_tree(&et, INODE_CACHE(dir), dx_root_bh);
+
+	/* XXX: What if dr_clusters is too large? */
+	while (le32_to_cpu(dx_root->dr_clusters)) {
+		ret = ocfs2_dx_dir_lookup_rec(dir, &dx_root->dr_list,
+					      major_hash, &cpos, &blkno, &clen);
+		if (ret) {
+			mlog_errno(ret);
+			goto out;
+		}
+
+		p_cpos = ocfs2_blocks_to_clusters(dir->i_sb, blkno);
+
+		ret = ocfs2_remove_btree_range(dir, &et, cpos, p_cpos, clen, 0,
+					       &dealloc, 0, false);
+		if (ret) {
+			mlog_errno(ret);
+			goto out;
+		}
+
+		if (cpos == 0)
+			break;
+
+		major_hash = cpos - 1;
+	}
+
+remove_index:
+	ret = ocfs2_dx_dir_remove_index(dir, di_bh, dx_root_bh);
+	if (ret) {
+		mlog_errno(ret);
+		goto out;
+	}
+
+	ocfs2_remove_from_cache(INODE_CACHE(dir), dx_root_bh);
+out:
+	ocfs2_schedule_truncate_log_flush(osb, 1);
+	ocfs2_run_deallocs(osb, &dealloc);
+
+	brelse(dx_root_bh);
+	return ret;
+}