[GFS2] The core of GFS2

This patch contains all the core files for GFS2.

Signed-off-by: David Teigland <teigland@redhat.com>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>

1 files changed, 2157 insertions, 0 deletions

diff --git a/fs/gfs2/dir.c b/fs/gfs2/dir.c
new file mode 100644
index 000000000000..6b1dc3dc3a2d
--- /dev/null
+++ b/fs/gfs2/dir.c
@@ -0,0 +1,2157 @@
+/*
+ * Copyright (C) Sistina Software, Inc.  1997-2003 All rights reserved.
+ * Copyright (C) 2004-2005 Red Hat, Inc.  All rights reserved.
+ *
+ * This copyrighted material is made available to anyone wishing to use,
+ * modify, copy, or redistribute it subject to the terms and conditions
+ * of the GNU General Public License v.2.
+ */
+
+/*
+* Implements Extendible Hashing as described in:
+*   "Extendible Hashing" by Fagin, et al in
+*     __ACM Trans. on Database Systems__, Sept 1979.
+*
+*
+* Here's the layout of dirents which is essentially the same as that of ext2
+* within a single block. The field de_name_len is the number of bytes
+* actually required for the name (no null terminator). The field de_rec_len
+* is the number of bytes allocated to the dirent. The offset of the next
+* dirent in the block is (dirent + dirent->de_rec_len). When a dirent is
+* deleted, the preceding dirent inherits its allocated space, ie
+* prev->de_rec_len += deleted->de_rec_len. Since the next dirent is obtained
+* by adding de_rec_len to the current dirent, this essentially causes the
+* deleted dirent to get jumped over when iterating through all the dirents.
+*
+* When deleting the first dirent in a block, there is no previous dirent so
+* the field de_ino is set to zero to designate it as deleted. When allocating
+* a dirent, gfs2_dirent_alloc iterates through the dirents in a block. If the
+* first dirent has (de_ino == 0) and de_rec_len is large enough, this first
+* dirent is allocated. Otherwise it must go through all the 'used' dirents
+* searching for one in which the amount of total space minus the amount of
+* used space will provide enough space for the new dirent.
+*
+* There are two types of blocks in which dirents reside. In a stuffed dinode,
+* the dirents begin at offset sizeof(struct gfs2_dinode) from the beginning of
+* the block.  In leaves, they begin at offset sizeof(struct gfs2_leaf) from the
+* beginning of the leaf block. The dirents reside in leaves when
+*
+* dip->i_di.di_flags & GFS2_DIF_EXHASH is true
+*
+* Otherwise, the dirents are "linear", within a single stuffed dinode block.
+*
+* When the dirents are in leaves, the actual contents of the directory file are
+* used as an array of 64-bit block pointers pointing to the leaf blocks. The
+* dirents are NOT in the directory file itself. There can be more than one block
+* pointer in the array that points to the same leaf. In fact, when a directory
+* is first converted from linear to exhash, all of the pointers point to the
+* same leaf.
+*
+* When a leaf is completely full, the size of the hash table can be
+* doubled unless it is already at the maximum size which is hard coded into
+* GFS2_DIR_MAX_DEPTH. After that, leaves are chained together in a linked list,
+* but never before the maximum hash table size has been reached.
+*/
+
+#include <linux/sched.h>
+#include <linux/slab.h>
+#include <linux/spinlock.h>
+#include <linux/completion.h>
+#include <linux/buffer_head.h>
+#include <linux/sort.h>
+#include <asm/semaphore.h>
+
+#include "gfs2.h"
+#include "dir.h"
+#include "glock.h"
+#include "inode.h"
+#include "jdata.h"
+#include "meta_io.h"
+#include "quota.h"
+#include "rgrp.h"
+#include "trans.h"
+
+#define IS_LEAF     1 /* Hashed (leaf) directory */
+#define IS_DINODE   2 /* Linear (stuffed dinode block) directory */
+
+#if 1
+#define gfs2_disk_hash2offset(h) (((uint64_t)(h)) >> 1)
+#define gfs2_dir_offset2hash(p) ((uint32_t)(((uint64_t)(p)) << 1))
+#else
+#define gfs2_disk_hash2offset(h) (((uint64_t)(h)))
+#define gfs2_dir_offset2hash(p) ((uint32_t)(((uint64_t)(p))))
+#endif
+
+typedef int (*leaf_call_t) (struct gfs2_inode *dip,
+			    uint32_t index, uint32_t len, uint64_t leaf_no,
+			    void *data);
+
+/**
+ * int gfs2_filecmp - Compare two filenames
+ * @file1: The first filename
+ * @file2: The second filename
+ * @len_of_file2: The length of the second file
+ *
+ * This routine compares two filenames and returns 1 if they are equal.
+ *
+ * Returns: 1 if the files are the same, otherwise 0.
+ */
+
+int gfs2_filecmp(struct qstr *file1, char *file2, int len_of_file2)
+{
+	if (file1->len != len_of_file2)
+		return 0;
+	if (memcmp(file1->name, file2, file1->len))
+		return 0;
+	return 1;
+}
+
+/**
+ * dirent_first - Return the first dirent
+ * @dip: the directory
+ * @bh: The buffer
+ * @dent: Pointer to list of dirents
+ *
+ * return first dirent whether bh points to leaf or stuffed dinode
+ *
+ * Returns: IS_LEAF, IS_DINODE, or -errno
+ */
+
+static int dirent_first(struct gfs2_inode *dip, struct buffer_head *bh,
+			struct gfs2_dirent **dent)
+{
+	struct gfs2_meta_header *h = (struct gfs2_meta_header *)bh->b_data;
+
+	if (be16_to_cpu(h->mh_type) == GFS2_METATYPE_LF) {
+		if (gfs2_meta_check(dip->i_sbd, bh))
+			return -EIO;
+		*dent = (struct gfs2_dirent *)(bh->b_data +
+					       sizeof(struct gfs2_leaf));
+		return IS_LEAF;
+	} else {
+		if (gfs2_metatype_check(dip->i_sbd, bh, GFS2_METATYPE_DI))
+			return -EIO;
+		*dent = (struct gfs2_dirent *)(bh->b_data +
+					       sizeof(struct gfs2_dinode));
+		return IS_DINODE;
+	}
+}
+
+/**
+ * dirent_next - Next dirent
+ * @dip: the directory
+ * @bh: The buffer
+ * @dent: Pointer to list of dirents
+ *
+ * Returns: 0 on success, error code otherwise
+ */
+
+static int dirent_next(struct gfs2_inode *dip, struct buffer_head *bh,
+		       struct gfs2_dirent **dent)
+{
+	struct gfs2_dirent *tmp, *cur;
+	char *bh_end;
+	uint32_t cur_rec_len;
+
+	cur = *dent;
+	bh_end = bh->b_data + bh->b_size;
+	cur_rec_len = be32_to_cpu(cur->de_rec_len);
+
+	if ((char *)cur + cur_rec_len >= bh_end) {
+		if ((char *)cur + cur_rec_len > bh_end) {
+			gfs2_consist_inode(dip);
+			return -EIO;
+		}
+		return -ENOENT;
+	}
+
+	tmp = (struct gfs2_dirent *)((char *)cur + cur_rec_len);
+
+	if ((char *)tmp + be32_to_cpu(tmp->de_rec_len) > bh_end) {
+		gfs2_consist_inode(dip);
+		return -EIO;
+	}
+        /* Only the first dent could ever have de_inum.no_addr == 0 */
+	if (!tmp->de_inum.no_addr) {
+		gfs2_consist_inode(dip);
+		return -EIO;
+	}
+
+	*dent = tmp;
+
+	return 0;
+}
+
+/**
+ * dirent_del - Delete a dirent
+ * @dip: The GFS2 inode
+ * @bh: The buffer
+ * @prev: The previous dirent
+ * @cur: The current dirent
+ *
+ */
+
+static void dirent_del(struct gfs2_inode *dip, struct buffer_head *bh,
+		       struct gfs2_dirent *prev, struct gfs2_dirent *cur)
+{
+	uint32_t cur_rec_len, prev_rec_len;
+
+	if (!cur->de_inum.no_addr) {
+		gfs2_consist_inode(dip);
+		return;
+	}
+
+	gfs2_trans_add_bh(dip->i_gl, bh);
+
+	/* If there is no prev entry, this is the first entry in the block.
+	   The de_rec_len is already as big as it needs to be.  Just zero
+	   out the inode number and return.  */
+
+	if (!prev) {
+		cur->de_inum.no_addr = 0;	/* No endianess worries */
+		return;
+	}
+
+	/*  Combine this dentry with the previous one.  */
+
+	prev_rec_len = be32_to_cpu(prev->de_rec_len);
+	cur_rec_len = be32_to_cpu(cur->de_rec_len);
+
+	if ((char *)prev + prev_rec_len != (char *)cur)
+		gfs2_consist_inode(dip);
+	if ((char *)cur + cur_rec_len > bh->b_data + bh->b_size)
+		gfs2_consist_inode(dip);
+
+	prev_rec_len += cur_rec_len;
+	prev->de_rec_len = cpu_to_be32(prev_rec_len);
+}
+
+/**
+ * gfs2_dirent_alloc - Allocate a directory entry
+ * @dip: The GFS2 inode
+ * @bh: The buffer
+ * @name_len: The length of the name
+ * @dent_out: Pointer to list of dirents
+ *
+ * Returns: 0 on success, error code otherwise
+ */
+
+int gfs2_dirent_alloc(struct gfs2_inode *dip, struct buffer_head *bh,
+		      int name_len, struct gfs2_dirent **dent_out)
+{
+	struct gfs2_dirent *dent, *new;
+	unsigned int rec_len = GFS2_DIRENT_SIZE(name_len);
+	unsigned int entries = 0, offset = 0;
+	int type;
+
+	type = dirent_first(dip, bh, &dent);
+	if (type < 0)
+		return type;
+
+	if (type == IS_LEAF) {
+		struct gfs2_leaf *leaf = (struct gfs2_leaf *)bh->b_data;
+		entries = be16_to_cpu(leaf->lf_entries);
+		offset = sizeof(struct gfs2_leaf);
+	} else {
+		struct gfs2_dinode *dinode = (struct gfs2_dinode *)bh->b_data;
+		entries = be32_to_cpu(dinode->di_entries);
+		offset = sizeof(struct gfs2_dinode);
+	}
+
+	if (!entries) {
+		if (dent->de_inum.no_addr) {
+			gfs2_consist_inode(dip);
+			return -EIO;
+		}
+
+		gfs2_trans_add_bh(dip->i_gl, bh);
+
+		dent->de_rec_len = bh->b_size - offset;
+		dent->de_rec_len = cpu_to_be32(dent->de_rec_len);
+		dent->de_name_len = name_len;
+
+		*dent_out = dent;
+		return 0;
+	}
+
+	do {
+		uint32_t cur_rec_len, cur_name_len;
+
+		cur_rec_len = be32_to_cpu(dent->de_rec_len);
+		cur_name_len = dent->de_name_len;
+
+		if ((!dent->de_inum.no_addr && cur_rec_len >= rec_len) ||
+		    (cur_rec_len >= GFS2_DIRENT_SIZE(cur_name_len) + rec_len)) {
+			gfs2_trans_add_bh(dip->i_gl, bh);
+
+			if (dent->de_inum.no_addr) {
+				new = (struct gfs2_dirent *)((char *)dent +
+							    GFS2_DIRENT_SIZE(cur_name_len));
+				memset(new, 0, sizeof(struct gfs2_dirent));
+
+				new->de_rec_len = cur_rec_len - GFS2_DIRENT_SIZE(cur_name_len);
+				new->de_rec_len = cpu_to_be32(new->de_rec_len);
+				new->de_name_len = name_len;
+
+				dent->de_rec_len = cur_rec_len - be32_to_cpu(new->de_rec_len);
+				dent->de_rec_len = cpu_to_be32(dent->de_rec_len);
+
+				*dent_out = new;
+				return 0;
+			}
+
+			dent->de_name_len = name_len;
+
+			*dent_out = dent;
+			return 0;
+		}
+	} while (dirent_next(dip, bh, &dent) == 0);
+
+	return -ENOSPC;
+}
+
+/**
+ * dirent_fits - See if we can fit a entry in this buffer
+ * @dip: The GFS2 inode
+ * @bh: The buffer
+ * @name_len: The length of the name
+ *
+ * Returns: 1 if it can fit, 0 otherwise
+ */
+
+static int dirent_fits(struct gfs2_inode *dip, struct buffer_head *bh,
+		       int name_len)
+{
+	struct gfs2_dirent *dent;
+	unsigned int rec_len = GFS2_DIRENT_SIZE(name_len);
+	unsigned int entries = 0;
+	int type;
+
+	type = dirent_first(dip, bh, &dent);
+	if (type < 0)
+		return type;
+
+	if (type == IS_LEAF) {
+		struct gfs2_leaf *leaf = (struct gfs2_leaf *)bh->b_data;
+		entries = be16_to_cpu(leaf->lf_entries);
+	} else {
+		struct gfs2_dinode *dinode = (struct gfs2_dinode *)bh->b_data;
+		entries = be32_to_cpu(dinode->di_entries);
+	}
+
+	if (!entries)
+		return 1;
+
+	do {
+		uint32_t cur_rec_len, cur_name_len;
+
+		cur_rec_len = be32_to_cpu(dent->de_rec_len);
+		cur_name_len = dent->de_name_len;
+
+		if ((!dent->de_inum.no_addr && cur_rec_len >= rec_len) ||
+		    (cur_rec_len >= GFS2_DIRENT_SIZE(cur_name_len) + rec_len))
+			return 1;
+	} while (dirent_next(dip, bh, &dent) == 0);
+
+	return 0;
+}
+
+static int leaf_search(struct gfs2_inode *dip, struct buffer_head *bh,
+		       struct qstr *filename, struct gfs2_dirent **dent_out,
+		       struct gfs2_dirent **dent_prev)
+{
+	uint32_t hash;
+	struct gfs2_dirent *dent, *prev = NULL;
+	unsigned int entries = 0;
+	int type;
+
+	type = dirent_first(dip, bh, &dent);
+	if (type < 0)
+		return type;
+
+	if (type == IS_LEAF) {
+		struct gfs2_leaf *leaf = (struct gfs2_leaf *)bh->b_data;
+		entries = be16_to_cpu(leaf->lf_entries);
+	} else if (type == IS_DINODE) {
+		struct gfs2_dinode *dinode = (struct gfs2_dinode *)bh->b_data;
+		entries = be32_to_cpu(dinode->di_entries);
+	}
+
+	hash = gfs2_disk_hash(filename->name, filename->len);
+
+	do {
+		if (!dent->de_inum.no_addr) {
+			prev = dent;
+			continue;
+		}
+
+		if (be32_to_cpu(dent->de_hash) == hash &&
+		    gfs2_filecmp(filename, (char *)(dent + 1),
+				 dent->de_name_len)) {
+			*dent_out = dent;
+			if (dent_prev)
+				*dent_prev = prev;
+
+			return 0;
+		}
+
+		prev = dent;
+	} while (dirent_next(dip, bh, &dent) == 0);
+
+	return -ENOENT;
+}
+
+static int get_leaf(struct gfs2_inode *dip, uint64_t leaf_no,
+		    struct buffer_head **bhp)
+{
+	int error;
+
+	error = gfs2_meta_read(dip->i_gl, leaf_no, DIO_START | DIO_WAIT, bhp);
+	if (!error && gfs2_metatype_check(dip->i_sbd, *bhp, GFS2_METATYPE_LF))
+		error = -EIO;
+
+	return error;
+}
+
+/**
+ * get_leaf_nr - Get a leaf number associated with the index
+ * @dip: The GFS2 inode
+ * @index:
+ * @leaf_out:
+ *
+ * Returns: 0 on success, error code otherwise
+ */
+
+static int get_leaf_nr(struct gfs2_inode *dip, uint32_t index,
+		       uint64_t *leaf_out)
+{
+	uint64_t leaf_no;
+	int error;
+
+	error = gfs2_jdata_read_mem(dip, (char *)&leaf_no,
+				    index * sizeof(uint64_t),
+				    sizeof(uint64_t));
+	if (error != sizeof(uint64_t))
+		return (error < 0) ? error : -EIO;
+
+	*leaf_out = be64_to_cpu(leaf_no);
+
+	return 0;
+}
+
+static int get_first_leaf(struct gfs2_inode *dip, uint32_t index,
+			  struct buffer_head **bh_out)
+{
+	uint64_t leaf_no;
+	int error;
+
+	error = get_leaf_nr(dip, index, &leaf_no);
+	if (!error)
+		error = get_leaf(dip, leaf_no, bh_out);
+
+	return error;
+}
+
+static int get_next_leaf(struct gfs2_inode *dip, struct buffer_head *bh_in,
+			 struct buffer_head **bh_out)
+{
+	struct gfs2_leaf *leaf;
+	int error;
+
+	leaf = (struct gfs2_leaf *)bh_in->b_data;
+
+	if (!leaf->lf_next)
+		error = -ENOENT;
+	else
+		error = get_leaf(dip, be64_to_cpu(leaf->lf_next), bh_out);
+
+	return error;
+}
+
+static int linked_leaf_search(struct gfs2_inode *dip, struct qstr *filename,
+			      struct gfs2_dirent **dent_out,
+			      struct gfs2_dirent **dent_prev,
+			      struct buffer_head **bh_out)
+{
+	struct buffer_head *bh = NULL, *bh_next;
+	uint32_t hsize, index;
+	uint32_t hash;
+	int error;
+
+	hsize = 1 << dip->i_di.di_depth;
+	if (hsize * sizeof(uint64_t) != dip->i_di.di_size) {
+		gfs2_consist_inode(dip);
+		return -EIO;
+	}
+
+	/*  Figure out the address of the leaf node.  */
+
+	hash = gfs2_disk_hash(filename->name, filename->len);
+	index = hash >> (32 - dip->i_di.di_depth);
+
+	error = get_first_leaf(dip, index, &bh_next);
+	if (error)
+		return error;
+
+	/*  Find the entry  */
+
+	do {
+		brelse(bh);
+
+		bh = bh_next;
+
+		error = leaf_search(dip, bh, filename, dent_out, dent_prev);
+		switch (error) {
+		case 0:
+			*bh_out = bh;
+			return 0;
+
+		case -ENOENT:
+			break;
+
+		default:
+			brelse(bh);
+			return error;
+		}
+
+		error = get_next_leaf(dip, bh, &bh_next);
+	}
+	while (!error);
+
+	brelse(bh);
+
+	return error;
+}
+
+/**
+ * dir_make_exhash - Convert a stuffed directory into an ExHash directory
+ * @dip: The GFS2 inode
+ *
+ * Returns: 0 on success, error code otherwise
+ */
+
+static int dir_make_exhash(struct gfs2_inode *dip)
+{
+	struct gfs2_sbd *sdp = dip->i_sbd;
+	struct gfs2_dirent *dent;
+	struct buffer_head *bh, *dibh;
+	struct gfs2_leaf *leaf;
+	int y;
+	uint32_t x;
+	uint64_t *lp, bn;
+	int error;
+
+	error = gfs2_meta_inode_buffer(dip, &dibh);
+	if (error)
+		return error;
+
+	/*  Allocate a new block for the first leaf node  */
+
+	bn = gfs2_alloc_meta(dip);
+
+	/*  Turn over a new leaf  */
+
+	bh = gfs2_meta_new(dip->i_gl, bn);
+	gfs2_trans_add_bh(dip->i_gl, bh);
+	gfs2_metatype_set(bh, GFS2_METATYPE_LF, GFS2_FORMAT_LF);
+	gfs2_buffer_clear_tail(bh, sizeof(struct gfs2_meta_header));
+
+	/*  Fill in the leaf structure  */
+
+	leaf = (struct gfs2_leaf *)bh->b_data;
+
+	gfs2_assert(sdp, dip->i_di.di_entries < (1 << 16));
+
+	leaf->lf_dirent_format = cpu_to_be32(GFS2_FORMAT_DE);
+	leaf->lf_entries = cpu_to_be16(dip->i_di.di_entries);
+
+	/*  Copy dirents  */
+
+	gfs2_buffer_copy_tail(bh, sizeof(struct gfs2_leaf), dibh,
+			     sizeof(struct gfs2_dinode));
+
+	/*  Find last entry  */
+
+	x = 0;
+	dirent_first(dip, bh, &dent);
+
+	do {
+		if (!dent->de_inum.no_addr)
+			continue;
+		if (++x == dip->i_di.di_entries)
+			break;
+	}
+	while (dirent_next(dip, bh, &dent) == 0);
+
+	/*  Adjust the last dirent's record length
+	   (Remember that dent still points to the last entry.)  */
+
+	dent->de_rec_len = be32_to_cpu(dent->de_rec_len) +
+		sizeof(struct gfs2_dinode) -
+		sizeof(struct gfs2_leaf);
+	dent->de_rec_len = cpu_to_be32(dent->de_rec_len);
+
+	brelse(bh);
+
+	/*  We're done with the new leaf block, now setup the new
+	    hash table.  */
+
+	gfs2_trans_add_bh(dip->i_gl, dibh);
+	gfs2_buffer_clear_tail(dibh, sizeof(struct gfs2_dinode));
+
+	lp = (uint64_t *)(dibh->b_data + sizeof(struct gfs2_dinode));
+
+	for (x = sdp->sd_hash_ptrs; x--; lp++)
+		*lp = cpu_to_be64(bn);
+
+	dip->i_di.di_size = sdp->sd_sb.sb_bsize / 2;
+	dip->i_di.di_blocks++;
+	dip->i_di.di_flags |= GFS2_DIF_EXHASH;
+	dip->i_di.di_payload_format = 0;
+
+	for (x = sdp->sd_hash_ptrs, y = -1; x; x >>= 1, y++) ;
+	dip->i_di.di_depth = y;
+
+	gfs2_dinode_out(&dip->i_di, dibh->b_data);
+
+	brelse(dibh);
+
+	return 0;
+}
+
+/**
+ * dir_split_leaf - Split a leaf block into two
+ * @dip: The GFS2 inode
+ * @index:
+ * @leaf_no:
+ *
+ * Returns: 0 on success, error code on failure
+ */
+
+static int dir_split_leaf(struct gfs2_inode *dip, uint32_t index,
+			  uint64_t leaf_no)
+{
+	struct buffer_head *nbh, *obh, *dibh;
+	struct gfs2_leaf *nleaf, *oleaf;
+	struct gfs2_dirent *dent, *prev = NULL, *next = NULL, *new;
+	uint32_t start, len, half_len, divider;
+	uint64_t bn, *lp;
+	uint32_t name_len;
+	int x, moved = 0;
+	int error;
+
+	/*  Allocate the new leaf block  */
+
+	bn = gfs2_alloc_meta(dip);
+
+	/*  Get the new leaf block  */
+
+	nbh = gfs2_meta_new(dip->i_gl, bn);
+	gfs2_trans_add_bh(dip->i_gl, nbh);
+	gfs2_metatype_set(nbh, GFS2_METATYPE_LF, GFS2_FORMAT_LF);
+	gfs2_buffer_clear_tail(nbh, sizeof(struct gfs2_meta_header));
+
+	nleaf = (struct gfs2_leaf *)nbh->b_data;
+
+	nleaf->lf_dirent_format = cpu_to_be32(GFS2_FORMAT_DE);
+
+	/*  Get the old leaf block  */
+
+	error = get_leaf(dip, leaf_no, &obh);
+	if (error)
+		goto fail;
+
+	gfs2_trans_add_bh(dip->i_gl, obh);
+
+	oleaf = (struct gfs2_leaf *)obh->b_data;
+
+	/*  Compute the start and len of leaf pointers in the hash table.  */
+
+	len = 1 << (dip->i_di.di_depth - be16_to_cpu(oleaf->lf_depth));
+	half_len = len >> 1;
+	if (!half_len) {
+		gfs2_consist_inode(dip);
+		error = -EIO;
+		goto fail_brelse;
+	}
+
+	start = (index & ~(len - 1));
+
+	/* Change the pointers.
+	   Don't bother distinguishing stuffed from non-stuffed.
+	   This code is complicated enough already. */
+
+	lp = kcalloc(half_len, sizeof(uint64_t), GFP_KERNEL | __GFP_NOFAIL);
+
+	error = gfs2_jdata_read_mem(dip, (char *)lp, start * sizeof(uint64_t),
+				    half_len * sizeof(uint64_t));
+	if (error != half_len * sizeof(uint64_t)) {
+		if (error >= 0)
+			error = -EIO;
+		goto fail_lpfree;
+	}
+
+	/*  Change the pointers  */
+
+	for (x = 0; x < half_len; x++)
+		lp[x] = cpu_to_be64(bn);
+
+	error = gfs2_jdata_write_mem(dip, (char *)lp, start * sizeof(uint64_t),
+				     half_len * sizeof(uint64_t));
+	if (error != half_len * sizeof(uint64_t)) {
+		if (error >= 0)
+			error = -EIO;
+		goto fail_lpfree;
+	}
+
+	kfree(lp);
+
+	/*  Compute the divider  */
+
+	divider = (start + half_len) << (32 - dip->i_di.di_depth);
+
+	/*  Copy the entries  */
+
+	dirent_first(dip, obh, &dent);
+
+	do {
+		next = dent;
+		if (dirent_next(dip, obh, &next))
+			next = NULL;
+
+		if (dent->de_inum.no_addr &&
+		    be32_to_cpu(dent->de_hash) < divider) {
+			name_len = dent->de_name_len;
+
+			gfs2_dirent_alloc(dip, nbh, name_len, &new);
+
+			new->de_inum = dent->de_inum; /* No endian worries */
+			new->de_hash = dent->de_hash; /* No endian worries */
+			new->de_type = dent->de_type; /* No endian worries */
+			memcpy((char *)(new + 1), (char *)(dent + 1),
+			       name_len);
+
+			nleaf->lf_entries = be16_to_cpu(nleaf->lf_entries)+1;
+			nleaf->lf_entries = cpu_to_be16(nleaf->lf_entries);
+
+			dirent_del(dip, obh, prev, dent);
+
+			if (!oleaf->lf_entries)
+				gfs2_consist_inode(dip);
+			oleaf->lf_entries = be16_to_cpu(oleaf->lf_entries)-1;
+			oleaf->lf_entries = cpu_to_be16(oleaf->lf_entries);
+
+			if (!prev)
+				prev = dent;
+
+			moved = 1;
+		} else
+			prev = dent;
+
+		dent = next;
+	}
+	while (dent);
+
+	/* If none of the entries got moved into the new leaf,
+	   artificially fill in the first entry. */
+
+	if (!moved) {
+		gfs2_dirent_alloc(dip, nbh, 0, &new);
+		new->de_inum.no_addr = 0;
+	}
+
+	oleaf->lf_depth = be16_to_cpu(oleaf->lf_depth) + 1;
+	oleaf->lf_depth = cpu_to_be16(oleaf->lf_depth);
+	nleaf->lf_depth = oleaf->lf_depth;
+
+	error = gfs2_meta_inode_buffer(dip, &dibh);
+	if (!gfs2_assert_withdraw(dip->i_sbd, !error)) {
+		dip->i_di.di_blocks++;
+		gfs2_dinode_out(&dip->i_di, dibh->b_data);
+		brelse(dibh);
+	}
+
+	brelse(obh);
+	brelse(nbh);
+
+	return error;
+
+ fail_lpfree:
+	kfree(lp);
+
+ fail_brelse:
+	brelse(obh);
+
+ fail:
+	brelse(nbh);
+	return error;
+}
+
+/**
+ * dir_double_exhash - Double size of ExHash table
+ * @dip: The GFS2 dinode
+ *
+ * Returns: 0 on success, error code on failure
+ */
+
+static int dir_double_exhash(struct gfs2_inode *dip)
+{
+	struct gfs2_sbd *sdp = dip->i_sbd;
+	struct buffer_head *dibh;
+	uint32_t hsize;
+	uint64_t *buf;
+	uint64_t *from, *to;
+	uint64_t block;
+	int x;
+	int error = 0;
+
+	hsize = 1 << dip->i_di.di_depth;
+	if (hsize * sizeof(uint64_t) != dip->i_di.di_size) {
+		gfs2_consist_inode(dip);
+		return -EIO;
+	}
+
+	/*  Allocate both the "from" and "to" buffers in one big chunk  */
+
+	buf = kcalloc(3, sdp->sd_hash_bsize, GFP_KERNEL | __GFP_NOFAIL);
+
+	for (block = dip->i_di.di_size >> sdp->sd_hash_bsize_shift; block--;) {
+		error = gfs2_jdata_read_mem(dip, (char *)buf,
+					    block * sdp->sd_hash_bsize,
+					    sdp->sd_hash_bsize);
+		if (error != sdp->sd_hash_bsize) {
+			if (error >= 0)
+				error = -EIO;
+			goto fail;
+		}
+
+		from = buf;
+		to = (uint64_t *)((char *)buf + sdp->sd_hash_bsize);
+
+		for (x = sdp->sd_hash_ptrs; x--; from++) {
+			*to++ = *from;	/*  No endianess worries  */
+			*to++ = *from;
+		}
+
+		error = gfs2_jdata_write_mem(dip,
+					     (char *)buf + sdp->sd_hash_bsize,
+					     block * sdp->sd_sb.sb_bsize,
+					     sdp->sd_sb.sb_bsize);
+		if (error != sdp->sd_sb.sb_bsize) {
+			if (error >= 0)
+				error = -EIO;
+			goto fail;
+		}
+	}
+
+	kfree(buf);
+
+	error = gfs2_meta_inode_buffer(dip, &dibh);
+	if (!gfs2_assert_withdraw(sdp, !error)) {
+		dip->i_di.di_depth++;
+		gfs2_dinode_out(&dip->i_di, dibh->b_data);
+		brelse(dibh);
+	}
+
+	return error;
+
+ fail:
+	kfree(buf);
+
+	return error;
+}
+
+/**
+ * compare_dents - compare directory entries by hash value
+ * @a: first dent
+ * @b: second dent
+ *
+ * When comparing the hash entries of @a to @b:
+ *   gt: returns 1
+ *   lt: returns -1
+ *   eq: returns 0
+ */
+
+static int compare_dents(const void *a, const void *b)
+{
+	struct gfs2_dirent *dent_a, *dent_b;
+	uint32_t hash_a, hash_b;
+	int ret = 0;
+
+	dent_a = *(struct gfs2_dirent **)a;
+	hash_a = dent_a->de_hash;
+	hash_a = be32_to_cpu(hash_a);
+
+	dent_b = *(struct gfs2_dirent **)b;
+	hash_b = dent_b->de_hash;
+	hash_b = be32_to_cpu(hash_b);
+
+	if (hash_a > hash_b)
+		ret = 1;
+	else if (hash_a < hash_b)
+		ret = -1;
+	else {
+		unsigned int len_a = dent_a->de_name_len;
+		unsigned int len_b = dent_b->de_name_len;
+
+		if (len_a > len_b)
+			ret = 1;
+		else if (len_a < len_b)
+			ret = -1;
+		else
+			ret = memcmp((char *)(dent_a + 1),
+				     (char *)(dent_b + 1),
+				     len_a);
+	}
+
+	return ret;
+}
+
+/**
+ * do_filldir_main - read out directory entries
+ * @dip: The GFS2 inode
+ * @offset: The offset in the file to read from
+ * @opaque: opaque data to pass to filldir
+ * @filldir: The function to pass entries to
+ * @darr: an array of struct gfs2_dirent pointers to read
+ * @entries: the number of entries in darr
+ * @copied: pointer to int that's non-zero if a entry has been copied out
+ *
+ * Jump through some hoops to make sure that if there are hash collsions,
+ * they are read out at the beginning of a buffer.  We want to minimize
+ * the possibility that they will fall into different readdir buffers or
+ * that someone will want to seek to that location.
+ *
+ * Returns: errno, >0 on exception from filldir
+ */
+
+static int do_filldir_main(struct gfs2_inode *dip, uint64_t *offset,
+			   void *opaque, gfs2_filldir_t filldir,
+			   struct gfs2_dirent **darr, uint32_t entries,
+			   int *copied)
+{
+	struct gfs2_dirent *dent, *dent_next;
+	struct gfs2_inum inum;
+	uint64_t off, off_next;
+	unsigned int x, y;
+	int run = 0;
+	int error = 0;
+
+	sort(darr, entries, sizeof(struct gfs2_dirent *), compare_dents, NULL);
+
+	dent_next = darr[0];
+	off_next = be32_to_cpu(dent_next->de_hash);
+	off_next = gfs2_disk_hash2offset(off_next);
+
+	for (x = 0, y = 1; x < entries; x++, y++) {
+		dent = dent_next;
+		off = off_next;
+
+		if (y < entries) {
+			dent_next = darr[y];
+			off_next = be32_to_cpu(dent_next->de_hash);
+			off_next = gfs2_disk_hash2offset(off_next);
+
+			if (off < *offset)
+				continue;
+			*offset = off;
+
+			if (off_next == off) {
+				if (*copied && !run)
+					return 1;
+				run = 1;
+			} else
+				run = 0;
+		} else {
+			if (off < *offset)
+				continue;
+			*offset = off;
+		}
+
+		gfs2_inum_in(&inum, (char *)&dent->de_inum);
+
+		error = filldir(opaque, (char *)(dent + 1),
+				dent->de_name_len,
+				off, &inum,
+				dent->de_type);
+		if (error)
+			return 1;
+
+		*copied = 1;
+	}
+
+	/* Increment the *offset by one, so the next time we come into the
+	   do_filldir fxn, we get the next entry instead of the last one in the
+	   current leaf */
+
+	(*offset)++;
+
+	return 0;
+}
+
+/**
+ * do_filldir_single - Read directory entries out of a single block
+ * @dip: The GFS2 inode
+ * @offset: The offset in the file to read from
+ * @opaque: opaque data to pass to filldir
+ * @filldir: The function to pass entries to
+ * @bh: the block
+ * @entries: the number of entries in the block
+ * @copied: pointer to int that's non-zero if a entry has been copied out
+ *
+ * Returns: errno, >0 on exception from filldir
+ */
+
+static int do_filldir_single(struct gfs2_inode *dip, uint64_t *offset,
+			     void *opaque, gfs2_filldir_t filldir,
+			     struct buffer_head *bh, uint32_t entries,
+			     int *copied)
+{
+	struct gfs2_dirent **darr;
+	struct gfs2_dirent *de;
+	unsigned int e = 0;
+	int error;
+
+	if (!entries)
+		return 0;
+
+	darr = kcalloc(entries, sizeof(struct gfs2_dirent *), GFP_KERNEL);
+	if (!darr)
+		return -ENOMEM;
+
+	dirent_first(dip, bh, &de);
+	do {
+		if (!de->de_inum.no_addr)
+			continue;
+		if (e >= entries) {
+			gfs2_consist_inode(dip);
+			error = -EIO;
+			goto out;
+		}
+		darr[e++] = de;
+	}
+	while (dirent_next(dip, bh, &de) == 0);
+
+	if (e != entries) {
+		gfs2_consist_inode(dip);
+		error = -EIO;
+		goto out;
+	}
+
+	error = do_filldir_main(dip, offset, opaque, filldir, darr,
+				entries, copied);
+
+ out:
+	kfree(darr);
+
+	return error;
+}
+
+/**
+ * do_filldir_multi - Read directory entries out of a linked leaf list
+ * @dip: The GFS2 inode
+ * @offset: The offset in the file to read from
+ * @opaque: opaque data to pass to filldir
+ * @filldir: The function to pass entries to
+ * @bh: the first leaf in the list
+ * @copied: pointer to int that's non-zero if a entry has been copied out
+ *
+ * Returns: errno, >0 on exception from filldir
+ */
+
+static int do_filldir_multi(struct gfs2_inode *dip, uint64_t *offset,
+			    void *opaque, gfs2_filldir_t filldir,
+			    struct buffer_head *bh, int *copied)
+{
+	struct buffer_head **larr = NULL;
+	struct gfs2_dirent **darr;
+	struct gfs2_leaf *leaf;
+	struct buffer_head *tmp_bh;
+	struct gfs2_dirent *de;
+	unsigned int entries, e = 0;
+	unsigned int leaves = 0, l = 0;
+	unsigned int x;
+	uint64_t ln;
+	int error = 0;
+
+	/*  Count leaves and entries  */
+
+	leaf = (struct gfs2_leaf *)bh->b_data;
+	entries = be16_to_cpu(leaf->lf_entries);
+	ln = leaf->lf_next;
+
+	while (ln) {
+		ln = be64_to_cpu(ln);
+
+		error = get_leaf(dip, ln, &tmp_bh);
+		if (error)
+			return error;
+
+		leaf = (struct gfs2_leaf *)tmp_bh->b_data;
+		if (leaf->lf_entries) {
+			entries += be16_to_cpu(leaf->lf_entries);
+			leaves++;
+		}
+		ln = leaf->lf_next;
+
+		brelse(tmp_bh);
+	}
+
+	if (!entries)
+		return 0;
+
+	if (leaves) {
+		larr = kcalloc(leaves, sizeof(struct buffer_head *),GFP_KERNEL);
+		if (!larr)
+			return -ENOMEM;
+	}
+
+	darr = kcalloc(entries, sizeof(struct gfs2_dirent *), GFP_KERNEL);
+	if (!darr) {
+		kfree(larr);
+		return -ENOMEM;
+	}
+
+	leaf = (struct gfs2_leaf *)bh->b_data;
+	if (leaf->lf_entries) {
+		dirent_first(dip, bh, &de);
+		do {
+			if (!de->de_inum.no_addr)
+				continue;
+			if (e >= entries) {
+				gfs2_consist_inode(dip);
+				error = -EIO;
+				goto out;
+			}
+			darr[e++] = de;
+		}
+		while (dirent_next(dip, bh, &de) == 0);
+	}
+	ln = leaf->lf_next;
+
+	while (ln) {
+		ln = be64_to_cpu(ln);
+
+		error = get_leaf(dip, ln, &tmp_bh);
+		if (error)
+			goto out;
+
+		leaf = (struct gfs2_leaf *)tmp_bh->b_data;
+		if (leaf->lf_entries) {
+			dirent_first(dip, tmp_bh, &de);
+			do {
+				if (!de->de_inum.no_addr)
+					continue;
+				if (e >= entries) {
+					gfs2_consist_inode(dip);
+					error = -EIO;
+					goto out;
+				}
+				darr[e++] = de;
+			}
+			while (dirent_next(dip, tmp_bh, &de) == 0);
+
+			larr[l++] = tmp_bh;
+
+			ln = leaf->lf_next;
+		} else {
+			ln = leaf->lf_next;
+			brelse(tmp_bh);
+		}
+	}
+
+	if (gfs2_assert_withdraw(dip->i_sbd, l == leaves)) {
+		error = -EIO;
+		goto out;
+	}
+	if (e != entries) {
+		gfs2_consist_inode(dip);
+		error = -EIO;
+		goto out;
+	}
+
+	error = do_filldir_main(dip, offset, opaque, filldir, darr,
+				entries, copied);
+
+ out:
+	kfree(darr);
+	for (x = 0; x < l; x++)
+		brelse(larr[x]);
+	kfree(larr);
+
+	return error;
+}
+
+/**
+ * dir_e_search - Search exhash (leaf) dir for inode matching name
+ * @dip: The GFS2 inode
+ * @filename: Filename string
+ * @inode: If non-NULL, function fills with formal inode # and block address
+ * @type: If non-NULL, function fills with DT_... dinode type
+ *
+ * Returns:
+ */
+
+static int dir_e_search(struct gfs2_inode *dip, struct qstr *filename,
+			struct gfs2_inum *inum, unsigned int *type)
+{
+	struct buffer_head *bh;
+	struct gfs2_dirent *dent;
+	int error;
+
+	error = linked_leaf_search(dip, filename, &dent, NULL, &bh);
+	if (error)
+		return error;
+
+	if (inum)
+		gfs2_inum_in(inum, (char *)&dent->de_inum);
+	if (type)
+		*type = dent->de_type;
+
+	brelse(bh);
+
+	return 0;
+}
+
+static int dir_e_add(struct gfs2_inode *dip, struct qstr *filename,
+		     struct gfs2_inum *inum, unsigned int type)
+{
+	struct buffer_head *bh, *nbh, *dibh;
+	struct gfs2_leaf *leaf, *nleaf;
+	struct gfs2_dirent *dent;
+	uint32_t hsize, index;
+	uint32_t hash;
+	uint64_t leaf_no, bn;
+	int error;
+
+ restart:
+	hsize = 1 << dip->i_di.di_depth;
+	if (hsize * sizeof(uint64_t) != dip->i_di.di_size) {
+		gfs2_consist_inode(dip);
+		return -EIO;
+	}
+
+	/*  Figure out the address of the leaf node.  */
+
+	hash = gfs2_disk_hash(filename->name, filename->len);
+	index = hash >> (32 - dip->i_di.di_depth);
+
+	error = get_leaf_nr(dip, index, &leaf_no);
+	if (error)
+		return error;
+
+	/*  Add entry to the leaf  */
+
+	for (;;) {
+		error = get_leaf(dip, leaf_no, &bh);
+		if (error)
+			return error;
+
+		leaf = (struct gfs2_leaf *)bh->b_data;
+
+		if (gfs2_dirent_alloc(dip, bh, filename->len, &dent)) {
+
+			if (be16_to_cpu(leaf->lf_depth) < dip->i_di.di_depth) {
+				/* Can we split the leaf? */
+
+				brelse(bh);
+
+				error = dir_split_leaf(dip, index, leaf_no);
+				if (error)
+					return error;
+
+				goto restart;
+
+			} else if (dip->i_di.di_depth < GFS2_DIR_MAX_DEPTH) {
+				/* Can we double the hash table? */
+
+				brelse(bh);
+
+				error = dir_double_exhash(dip);
+				if (error)
+					return error;
+
+				goto restart;
+
+			} else if (leaf->lf_next) {
+				/* Can we try the next leaf in the list? */
+				leaf_no = be64_to_cpu(leaf->lf_next);
+				brelse(bh);
+				continue;
+
+			} else {
+				/* Create a new leaf and add it to the list. */
+
+				bn = gfs2_alloc_meta(dip);
+
+				nbh = gfs2_meta_new(dip->i_gl, bn);
+				gfs2_trans_add_bh(dip->i_gl, nbh);
+				gfs2_metatype_set(nbh,
+						 GFS2_METATYPE_LF,
+						 GFS2_FORMAT_LF);
+				gfs2_buffer_clear_tail(nbh,
+					sizeof(struct gfs2_meta_header));
+
+				gfs2_trans_add_bh(dip->i_gl, bh);
+				leaf->lf_next = cpu_to_be64(bn);
+
+				nleaf = (struct gfs2_leaf *)nbh->b_data;
+				nleaf->lf_depth = leaf->lf_depth;
+				nleaf->lf_dirent_format = cpu_to_be32(GFS2_FORMAT_DE);
+
+				gfs2_dirent_alloc(dip, nbh, filename->len,
+						  &dent);
+
+				dip->i_di.di_blocks++;
+
+				brelse(bh);
+
+				bh = nbh;
+				leaf = nleaf;
+			}
+		}
+
+		/* If the gfs2_dirent_alloc() succeeded, it pinned the "bh" */
+
+		gfs2_inum_out(inum, (char *)&dent->de_inum);
+		dent->de_hash = cpu_to_be32(hash);
+		dent->de_type = type;
+		memcpy((char *)(dent + 1), filename->name, filename->len);
+
+		leaf->lf_entries = be16_to_cpu(leaf->lf_entries) + 1;
+		leaf->lf_entries = cpu_to_be16(leaf->lf_entries);
+
+		brelse(bh);
+
+		error = gfs2_meta_inode_buffer(dip, &dibh);
+		if (error)
+			return error;
+
+		dip->i_di.di_entries++;
+		dip->i_di.di_mtime = dip->i_di.di_ctime = get_seconds();
+
+		gfs2_trans_add_bh(dip->i_gl, dibh);
+		gfs2_dinode_out(&dip->i_di, dibh->b_data);
+		brelse(dibh);
+
+		return 0;
+	}
+
+	return -ENOENT;
+}
+
+static int dir_e_del(struct gfs2_inode *dip, struct qstr *filename)
+{
+	struct buffer_head *bh, *dibh;
+	struct gfs2_dirent *dent, *prev;
+	struct gfs2_leaf *leaf;
+	unsigned int entries;
+	int error;
+
+	error = linked_leaf_search(dip, filename, &dent, &prev, &bh);
+	if (error == -ENOENT) {
+		gfs2_consist_inode(dip);
+		return -EIO;
+	}
+	if (error)
+		return error;
+
+	dirent_del(dip, bh, prev, dent); /* Pins bh */
+
+	leaf = (struct gfs2_leaf *)bh->b_data;
+	entries = be16_to_cpu(leaf->lf_entries);
+	if (!entries)
+		gfs2_consist_inode(dip);
+	entries--;
+	leaf->lf_entries = cpu_to_be16(entries);
+
+	brelse(bh);
+
+	error = gfs2_meta_inode_buffer(dip, &dibh);
+	if (error)
+		return error;
+
+	if (!dip->i_di.di_entries)
+		gfs2_consist_inode(dip);
+	dip->i_di.di_entries--;
+	dip->i_di.di_mtime = dip->i_di.di_ctime = get_seconds();
+
+	gfs2_trans_add_bh(dip->i_gl, dibh);
+	gfs2_dinode_out(&dip->i_di, dibh->b_data);
+	brelse(dibh);
+
+	return 0;
+}
+
+/**
+ * dir_e_read - Reads the entries from a directory into a filldir buffer
+ * @dip: dinode pointer
+ * @offset: the hash of the last entry read shifted to the right once
+ * @opaque: buffer for the filldir function to fill
+ * @filldir: points to the filldir function to use
+ *
+ * Returns: errno
+ */
+
+static int dir_e_read(struct gfs2_inode *dip, uint64_t *offset, void *opaque,
+		      gfs2_filldir_t filldir)
+{
+	struct gfs2_sbd *sdp = dip->i_sbd;
+	struct buffer_head *bh;
+	struct gfs2_leaf leaf;
+	uint32_t hsize, len;
+	uint32_t ht_offset, lp_offset, ht_offset_cur = -1;
+	uint32_t hash, index;
+	uint64_t *lp;
+	int copied = 0;
+	int error = 0;
+
+	hsize = 1 << dip->i_di.di_depth;
+	if (hsize * sizeof(uint64_t) != dip->i_di.di_size) {
+		gfs2_consist_inode(dip);
+		return -EIO;
+	}
+
+	hash = gfs2_dir_offset2hash(*offset);
+	index = hash >> (32 - dip->i_di.di_depth);
+
+	lp = kmalloc(sdp->sd_hash_bsize, GFP_KERNEL);
+	if (!lp)
+		return -ENOMEM;
+
+	while (index < hsize) {
+		lp_offset = index & (sdp->sd_hash_ptrs - 1);
+		ht_offset = index - lp_offset;
+
+		if (ht_offset_cur != ht_offset) {
+			error = gfs2_jdata_read_mem(dip, (char *)lp,
+						ht_offset * sizeof(uint64_t),
+						sdp->sd_hash_bsize);
+			if (error != sdp->sd_hash_bsize) {
+				if (error >= 0)
+					error = -EIO;
+				goto out;
+			}
+			ht_offset_cur = ht_offset;
+		}
+
+		error = get_leaf(dip, be64_to_cpu(lp[lp_offset]), &bh);
+		if (error)
+			goto out;
+
+		gfs2_leaf_in(&leaf, bh->b_data);
+
+		if (leaf.lf_next)
+			error = do_filldir_multi(dip, offset, opaque, filldir,
+						 bh, &copied);
+		else
+			error = do_filldir_single(dip, offset, opaque, filldir,
+						  bh, leaf.lf_entries, &copied);
+
+		brelse(bh);
+
+		if (error) {
+			if (error > 0)
+				error = 0;
+			goto out;
+		}
+
+		len = 1 << (dip->i_di.di_depth - leaf.lf_depth);
+		index = (index & ~(len - 1)) + len;
+	}
+
+ out:
+	kfree(lp);
+
+	return error;
+}
+
+static int dir_e_mvino(struct gfs2_inode *dip, struct qstr *filename,
+		       struct gfs2_inum *inum, unsigned int new_type)
+{
+	struct buffer_head *bh, *dibh;
+	struct gfs2_dirent *dent;
+	int error;
+
+	error = linked_leaf_search(dip, filename, &dent, NULL, &bh);
+	if (error == -ENOENT) {
+		gfs2_consist_inode(dip);
+		return -EIO;
+	}
+	if (error)
+		return error;
+
+	gfs2_trans_add_bh(dip->i_gl, bh);
+
+	gfs2_inum_out(inum, (char *)&dent->de_inum);
+	dent->de_type = new_type;
+
+	brelse(bh);
+
+	error = gfs2_meta_inode_buffer(dip, &dibh);
+	if (error)
+		return error;
+
+	dip->i_di.di_mtime = dip->i_di.di_ctime = get_seconds();
+
+	gfs2_trans_add_bh(dip->i_gl, dibh);
+	gfs2_dinode_out(&dip->i_di, dibh->b_data);
+	brelse(dibh);
+
+	return 0;
+}
+
+/**
+ * dir_l_search - Search linear (stuffed dinode) dir for inode matching name
+ * @dip: The GFS2 inode
+ * @filename: Filename string
+ * @inode: If non-NULL, function fills with formal inode # and block address
+ * @type: If non-NULL, function fills with DT_... dinode type
+ *
+ * Returns:
+ */
+
+static int dir_l_search(struct gfs2_inode *dip, struct qstr *filename,
+			struct gfs2_inum *inum, unsigned int *type)
+{
+	struct buffer_head *dibh;
+	struct gfs2_dirent *dent;
+	int error;
+
+	if (!gfs2_is_stuffed(dip)) {
+		gfs2_consist_inode(dip);
+		return -EIO;
+	}
+
+	error = gfs2_meta_inode_buffer(dip, &dibh);
+	if (error)
+		return error;
+
+	error = leaf_search(dip, dibh, filename, &dent, NULL);
+	if (!error) {
+		if (inum)
+			gfs2_inum_in(inum, (char *)&dent->de_inum);
+		if (type)
+			*type = dent->de_type;
+	}
+
+	brelse(dibh);
+
+	return error;
+}
+
+static int dir_l_add(struct gfs2_inode *dip, struct qstr *filename,
+		     struct gfs2_inum *inum, unsigned int type)
+{
+	struct buffer_head *dibh;
+	struct gfs2_dirent *dent;
+	int error;
+
+	if (!gfs2_is_stuffed(dip)) {
+		gfs2_consist_inode(dip);
+		return -EIO;
+	}
+
+	error = gfs2_meta_inode_buffer(dip, &dibh);
+	if (error)
+		return error;
+
+	if (gfs2_dirent_alloc(dip, dibh, filename->len, &dent)) {
+		brelse(dibh);
+
+		error = dir_make_exhash(dip);
+		if (!error)
+			error = dir_e_add(dip, filename, inum, type);
+
+		return error;
+	}
+
+	/*  gfs2_dirent_alloc() pins  */
+
+	gfs2_inum_out(inum, (char *)&dent->de_inum);
+	dent->de_hash = gfs2_disk_hash(filename->name, filename->len);
+	dent->de_hash = cpu_to_be32(dent->de_hash);
+	dent->de_type = type;
+	memcpy((char *)(dent + 1), filename->name, filename->len);
+
+	dip->i_di.di_entries++;
+	dip->i_di.di_mtime = dip->i_di.di_ctime = get_seconds();
+
+	gfs2_dinode_out(&dip->i_di, dibh->b_data);
+	brelse(dibh);
+
+	return 0;
+}
+
+static int dir_l_del(struct gfs2_inode *dip, struct qstr *filename)
+{
+	struct buffer_head *dibh;
+	struct gfs2_dirent *dent, *prev;
+	int error;
+
+	if (!gfs2_is_stuffed(dip)) {
+		gfs2_consist_inode(dip);
+		return -EIO;
+	}
+
+	error = gfs2_meta_inode_buffer(dip, &dibh);
+	if (error)
+		return error;
+
+	error = leaf_search(dip, dibh, filename, &dent, &prev);
+	if (error == -ENOENT) {
+		gfs2_consist_inode(dip);
+		error = -EIO;
+		goto out;
+	}
+	if (error)
+		goto out;
+
+	dirent_del(dip, dibh, prev, dent);
+
+	/*  dirent_del() pins  */
+
+	if (!dip->i_di.di_entries)
+		gfs2_consist_inode(dip);
+	dip->i_di.di_entries--;
+
+	dip->i_di.di_mtime = dip->i_di.di_ctime = get_seconds();
+
+	gfs2_dinode_out(&dip->i_di, dibh->b_data);
+
+ out:
+	brelse(dibh);
+
+	return error;
+}
+
+static int dir_l_read(struct gfs2_inode *dip, uint64_t *offset, void *opaque,
+		      gfs2_filldir_t filldir)
+{
+	struct buffer_head *dibh;
+	int copied = 0;
+	int error;
+
+	if (!gfs2_is_stuffed(dip)) {
+		gfs2_consist_inode(dip);
+		return -EIO;
+	}
+
+	if (!dip->i_di.di_entries)
+		return 0;
+
+	error = gfs2_meta_inode_buffer(dip, &dibh);
+	if (error)
+		return error;
+
+	error = do_filldir_single(dip, offset,
+				  opaque, filldir,
+				  dibh, dip->i_di.di_entries,
+				  &copied);
+	if (error > 0)
+		error = 0;
+
+	brelse(dibh);
+
+	return error;
+}
+
+static int dir_l_mvino(struct gfs2_inode *dip, struct qstr *filename,
+		       struct gfs2_inum *inum, unsigned int new_type)
+{
+	struct buffer_head *dibh;
+	struct gfs2_dirent *dent;
+	int error;
+
+	if (!gfs2_is_stuffed(dip)) {
+		gfs2_consist_inode(dip);
+		return -EIO;
+	}
+
+	error = gfs2_meta_inode_buffer(dip, &dibh);
+	if (error)
+		return error;
+
+	error = leaf_search(dip, dibh, filename, &dent, NULL);
+	if (error == -ENOENT) {
+		gfs2_consist_inode(dip);
+		error = -EIO;
+		goto out;
+	}
+	if (error)
+		goto out;
+
+	gfs2_trans_add_bh(dip->i_gl, dibh);
+
+	gfs2_inum_out(inum, (char *)&dent->de_inum);
+	dent->de_type = new_type;
+
+	dip->i_di.di_mtime = dip->i_di.di_ctime = get_seconds();
+
+	gfs2_dinode_out(&dip->i_di, dibh->b_data);
+
+ out:
+	brelse(dibh);
+
+	return error;
+}
+
+/**
+ * gfs2_dir_search - Search a directory
+ * @dip: The GFS2 inode
+ * @filename:
+ * @inode:
+ *
+ * This routine searches a directory for a file or another directory.
+ * Assumes a glock is held on dip.
+ *
+ * Returns: errno
+ */
+
+int gfs2_dir_search(struct gfs2_inode *dip, struct qstr *filename,
+		    struct gfs2_inum *inum, unsigned int *type)
+{
+	int error;
+
+	if (dip->i_di.di_flags & GFS2_DIF_EXHASH)
+		error = dir_e_search(dip, filename, inum, type);
+	else
+		error = dir_l_search(dip, filename, inum, type);
+
+	return error;
+}
+
+/**
+ * gfs2_dir_add - Add new filename into directory
+ * @dip: The GFS2 inode
+ * @filename: The new name
+ * @inode: The inode number of the entry
+ * @type: The type of the entry
+ *
+ * Returns: 0 on success, error code on failure
+ */
+
+int gfs2_dir_add(struct gfs2_inode *dip, struct qstr *filename,
+		 struct gfs2_inum *inum, unsigned int type)
+{
+	int error;
+
+	if (dip->i_di.di_flags & GFS2_DIF_EXHASH)
+		error = dir_e_add(dip, filename, inum, type);
+	else
+		error = dir_l_add(dip, filename, inum, type);
+
+	return error;
+}
+
+/**
+ * gfs2_dir_del - Delete a directory entry
+ * @dip: The GFS2 inode
+ * @filename: The filename
+ *
+ * Returns: 0 on success, error code on failure
+ */
+
+int gfs2_dir_del(struct gfs2_inode *dip, struct qstr *filename)
+{
+	int error;
+
+	if (dip->i_di.di_flags & GFS2_DIF_EXHASH)
+		error = dir_e_del(dip, filename);
+	else
+		error = dir_l_del(dip, filename);
+
+	return error;
+}
+
+int gfs2_dir_read(struct gfs2_inode *dip, uint64_t *offset, void *opaque,
+		  gfs2_filldir_t filldir)
+{
+	int error;
+
+	if (dip->i_di.di_flags & GFS2_DIF_EXHASH)
+		error = dir_e_read(dip, offset, opaque, filldir);
+	else
+		error = dir_l_read(dip, offset, opaque, filldir);
+
+	return error;
+}
+
+/**
+ * gfs2_dir_mvino - Change inode number of directory entry
+ * @dip: The GFS2 inode
+ * @filename:
+ * @new_inode:
+ *
+ * This routine changes the inode number of a directory entry.  It's used
+ * by rename to change ".." when a directory is moved.
+ * Assumes a glock is held on dvp.
+ *
+ * Returns: errno
+ */
+
+int gfs2_dir_mvino(struct gfs2_inode *dip, struct qstr *filename,
+		   struct gfs2_inum *inum, unsigned int new_type)
+{
+	int error;
+
+	if (dip->i_di.di_flags & GFS2_DIF_EXHASH)
+		error = dir_e_mvino(dip, filename, inum, new_type);
+	else
+		error = dir_l_mvino(dip, filename, inum, new_type);
+
+	return error;
+}
+
+/**
+ * foreach_leaf - call a function for each leaf in a directory
+ * @dip: the directory
+ * @lc: the function to call for each each
+ * @data: private data to pass to it
+ *
+ * Returns: errno
+ */
+
+static int foreach_leaf(struct gfs2_inode *dip, leaf_call_t lc, void *data)
+{
+	struct gfs2_sbd *sdp = dip->i_sbd;
+	struct buffer_head *bh;
+	struct gfs2_leaf leaf;
+	uint32_t hsize, len;
+	uint32_t ht_offset, lp_offset, ht_offset_cur = -1;
+	uint32_t index = 0;
+	uint64_t *lp;
+	uint64_t leaf_no;
+	int error = 0;
+
+	hsize = 1 << dip->i_di.di_depth;
+	if (hsize * sizeof(uint64_t) != dip->i_di.di_size) {
+		gfs2_consist_inode(dip);
+		return -EIO;
+	}
+
+	lp = kmalloc(sdp->sd_hash_bsize, GFP_KERNEL);
+	if (!lp)
+		return -ENOMEM;
+
+	while (index < hsize) {
+		lp_offset = index & (sdp->sd_hash_ptrs - 1);
+		ht_offset = index - lp_offset;
+
+		if (ht_offset_cur != ht_offset) {
+			error = gfs2_jdata_read_mem(dip, (char *)lp,
+						ht_offset * sizeof(uint64_t),
+						sdp->sd_hash_bsize);
+			if (error != sdp->sd_hash_bsize) {
+				if (error >= 0)
+					error = -EIO;
+				goto out;
+			}
+			ht_offset_cur = ht_offset;
+		}
+
+		leaf_no = be64_to_cpu(lp[lp_offset]);
+		if (leaf_no) {
+			error = get_leaf(dip, leaf_no, &bh);
+			if (error)
+				goto out;
+			gfs2_leaf_in(&leaf, bh->b_data);
+			brelse(bh);
+
+			len = 1 << (dip->i_di.di_depth - leaf.lf_depth);
+
+			error = lc(dip, index, len, leaf_no, data);
+			if (error)
+				goto out;
+
+			index = (index & ~(len - 1)) + len;
+		} else
+			index++;
+	}
+
+	if (index != hsize) {
+		gfs2_consist_inode(dip);
+		error = -EIO;
+	}
+
+ out:
+	kfree(lp);
+
+	return error;
+}
+
+/**
+ * leaf_dealloc - Deallocate a directory leaf
+ * @dip: the directory
+ * @index: the hash table offset in the directory
+ * @len: the number of pointers to this leaf
+ * @leaf_no: the leaf number
+ * @data: not used
+ *
+ * Returns: errno
+ */
+
+static int leaf_dealloc(struct gfs2_inode *dip, uint32_t index, uint32_t len,
+			uint64_t leaf_no, void *data)
+{
+	struct gfs2_sbd *sdp = dip->i_sbd;
+	struct gfs2_leaf tmp_leaf;
+	struct gfs2_rgrp_list rlist;
+	struct buffer_head *bh, *dibh;
+	uint64_t blk;
+	unsigned int rg_blocks = 0, l_blocks = 0;
+	char *ht;
+	unsigned int x, size = len * sizeof(uint64_t);
+	int error;
+
+	memset(&rlist, 0, sizeof(struct gfs2_rgrp_list));
+
+	ht = kzalloc(size, GFP_KERNEL);
+	if (!ht)
+		return -ENOMEM;
+
+	gfs2_alloc_get(dip);
+
+	error = gfs2_quota_hold(dip, NO_QUOTA_CHANGE, NO_QUOTA_CHANGE);
+	if (error)
+		goto out;
+
+	error = gfs2_rindex_hold(sdp, &dip->i_alloc.al_ri_gh);
+	if (error)
+		goto out_qs;
+
+	/*  Count the number of leaves  */
+
+	for (blk = leaf_no; blk; blk = tmp_leaf.lf_next) {
+		error = get_leaf(dip, blk, &bh);
+		if (error)
+			goto out_rlist;
+		gfs2_leaf_in(&tmp_leaf, (bh)->b_data);
+		brelse(bh);
+
+		gfs2_rlist_add(sdp, &rlist, blk);
+		l_blocks++;
+	}
+
+	gfs2_rlist_alloc(&rlist, LM_ST_EXCLUSIVE, 0);
+
+	for (x = 0; x < rlist.rl_rgrps; x++) {
+		struct gfs2_rgrpd *rgd;
+		rgd = get_gl2rgd(rlist.rl_ghs[x].gh_gl);
+		rg_blocks += rgd->rd_ri.ri_length;
+	}
+
+	error = gfs2_glock_nq_m(rlist.rl_rgrps, rlist.rl_ghs);
+	if (error)
+		goto out_rlist;
+
+	error = gfs2_trans_begin(sdp,
+			rg_blocks + (DIV_RU(size, sdp->sd_jbsize) + 1) +
+			RES_DINODE + RES_STATFS + RES_QUOTA, l_blocks);
+	if (error)
+		goto out_rg_gunlock;
+
+	for (blk = leaf_no; blk; blk = tmp_leaf.lf_next) {
+		error = get_leaf(dip, blk, &bh);
+		if (error)
+			goto out_end_trans;
+		gfs2_leaf_in(&tmp_leaf, bh->b_data);
+		brelse(bh);
+
+		gfs2_free_meta(dip, blk, 1);
+
+		if (!dip->i_di.di_blocks)
+			gfs2_consist_inode(dip);
+		dip->i_di.di_blocks--;
+	}
+
+	error = gfs2_jdata_write_mem(dip, ht, index * sizeof(uint64_t), size);
+	if (error != size) {
+		if (error >= 0)
+			error = -EIO;
+		goto out_end_trans;
+	}
+
+	error = gfs2_meta_inode_buffer(dip, &dibh);
+	if (error)
+		goto out_end_trans;
+
+	gfs2_trans_add_bh(dip->i_gl, dibh);
+	gfs2_dinode_out(&dip->i_di, dibh->b_data);
+	brelse(dibh);
+
+ out_end_trans:
+	gfs2_trans_end(sdp);
+
+ out_rg_gunlock:
+	gfs2_glock_dq_m(rlist.rl_rgrps, rlist.rl_ghs);
+
+ out_rlist:
+	gfs2_rlist_free(&rlist);
+	gfs2_glock_dq_uninit(&dip->i_alloc.al_ri_gh);
+
+ out_qs:
+	gfs2_quota_unhold(dip);
+
+ out:
+	gfs2_alloc_put(dip);
+	kfree(ht);
+
+	return error;
+}
+
+/**
+ * gfs2_dir_exhash_dealloc - free all the leaf blocks in a directory
+ * @dip: the directory
+ *
+ * Dealloc all on-disk directory leaves to FREEMETA state
+ * Change on-disk inode type to "regular file"
+ *
+ * Returns: errno
+ */
+
+int gfs2_dir_exhash_dealloc(struct gfs2_inode *dip)
+{
+	struct gfs2_sbd *sdp = dip->i_sbd;
+	struct buffer_head *bh;
+	int error;
+
+	/* Dealloc on-disk leaves to FREEMETA state */
+	error = foreach_leaf(dip, leaf_dealloc, NULL);
+	if (error)
+		return error;
+
+	/* Make this a regular file in case we crash.
+	   (We don't want to free these blocks a second time.)  */
+
+	error = gfs2_trans_begin(sdp, RES_DINODE, 0);
+	if (error)
+		return error;
+
+	error = gfs2_meta_inode_buffer(dip, &bh);
+	if (!error) {
+		gfs2_trans_add_bh(dip->i_gl, bh);
+		((struct gfs2_dinode *)bh->b_data)->di_mode = cpu_to_be32(S_IFREG);
+		brelse(bh);
+	}
+
+	gfs2_trans_end(sdp);
+
+	return error;
+}
+
+/**
+ * gfs2_diradd_alloc_required - find if adding entry will require an allocation
+ * @ip: the file being written to
+ * @filname: the filename that's going to be added
+ * @alloc_required: set to 1 if an alloc is required, 0 otherwise
+ *
+ * Returns: errno
+ */
+
+int gfs2_diradd_alloc_required(struct gfs2_inode *dip, struct qstr *filename,
+			       int *alloc_required)
+{
+	struct buffer_head *bh = NULL, *bh_next;
+	uint32_t hsize, hash, index;
+	int error = 0;
+
+	*alloc_required = 0;
+
+	if (dip->i_di.di_flags & GFS2_DIF_EXHASH) {
+		hsize = 1 << dip->i_di.di_depth;
+		if (hsize * sizeof(uint64_t) != dip->i_di.di_size) {
+			gfs2_consist_inode(dip);
+			return -EIO;
+		}
+
+		hash = gfs2_disk_hash(filename->name, filename->len);
+		index = hash >> (32 - dip->i_di.di_depth);
+
+		error = get_first_leaf(dip, index, &bh_next);
+		if (error)
+			return error;
+
+		do {
+			brelse(bh);
+
+			bh = bh_next;
+
+			if (dirent_fits(dip, bh, filename->len))
+				break;
+
+			error = get_next_leaf(dip, bh, &bh_next);
+			if (error == -ENOENT) {
+				*alloc_required = 1;
+				error = 0;
+				break;
+			}
+		}
+		while (!error);
+
+		brelse(bh);
+	} else {
+		error = gfs2_meta_inode_buffer(dip, &bh);
+		if (error)
+			return error;
+
+		if (!dirent_fits(dip, bh, filename->len))
+			*alloc_required = 1;
+
+		brelse(bh);
+	}
+
+	return error;
+}
+
+/**
+ * do_gdm - copy out one leaf (or list of leaves)
+ * @dip: the directory
+ * @index: the hash table offset in the directory
+ * @len: the number of pointers to this leaf
+ * @leaf_no: the leaf number
+ * @data: a pointer to a struct gfs2_user_buffer structure
+ *
+ * Returns: errno
+ */
+
+static int do_gdm(struct gfs2_inode *dip, uint32_t index, uint32_t len,
+		  uint64_t leaf_no, void *data)
+{
+	struct gfs2_user_buffer *ub = (struct gfs2_user_buffer *)data;
+	struct gfs2_leaf leaf;
+	struct buffer_head *bh;
+	uint64_t blk;
+	int error = 0;
+
+	for (blk = leaf_no; blk; blk = leaf.lf_next) {
+		error = get_leaf(dip, blk, &bh);
+		if (error)
+			break;
+
+		gfs2_leaf_in(&leaf, bh->b_data);
+
+		error = gfs2_add_bh_to_ub(ub, bh);
+
+		brelse(bh);
+
+		if (error)
+			break;
+	}
+
+	return error;
+}
+
+/**
+ * gfs2_get_dir_meta - return all the leaf blocks of a directory
+ * @dip: the directory
+ * @ub: the structure representing the meta
+ *
+ * Returns: errno
+ */
+
+int gfs2_get_dir_meta(struct gfs2_inode *dip, struct gfs2_user_buffer *ub)
+{
+	return foreach_leaf(dip, do_gdm, ub);
+}
+