Code that handles directory operations.

Signed-off-by: Ken Preslan <[EMAIL PROTECTED]>
Signed-off-by: David Teigland <[EMAIL PROTECTED]>

---

 fs/gfs2/dir.c | 2158 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
 fs/gfs2/dir.h |   51 +
 2 files changed, 2209 insertions(+)

--- a/fs/gfs2/dir.c     1970-01-01 07:30:00.000000000 +0730
+++ b/fs/gfs2/dir.c     2005-09-01 17:36:55.180135992 +0800
@@ -0,0 +1,2158 @@
+/*
+ * 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/smp_lock.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 TRUE if they are equal.
+ *
+ * Returns: TRUE (!=0) if the files are the same, otherwise FALSE (0).
+ */
+
+int gfs2_filecmp(struct qstr *file1, char *file2, int len_of_file2)
+{
+       if (file1->len != len_of_file2)
+               return FALSE;
+       if (memcmp(file1->name, file2, file1->len))
+               return FALSE;
+       return TRUE;
+}
+
+/**
+ * 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 (gfs2_16_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 = gfs2_32_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 + gfs2_32_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 = gfs2_32_to_cpu(prev->de_rec_len);
+       cur_rec_len = gfs2_32_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_gfs2_32(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 = gfs2_16_to_cpu(leaf->lf_entries);
+               offset = sizeof(struct gfs2_leaf);
+       } else {
+               struct gfs2_dinode *dinode = (struct gfs2_dinode *)bh->b_data;
+               entries = gfs2_32_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_gfs2_32(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 = gfs2_32_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_gfs2_32(new->de_rec_len);
+                               new->de_name_len = name_len;
+
+                               dent->de_rec_len = cur_rec_len - 
gfs2_32_to_cpu(new->de_rec_len);
+                               dent->de_rec_len = 
cpu_to_gfs2_32(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: TRUE if it can fit, FALSE 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 = gfs2_16_to_cpu(leaf->lf_entries);
+       } else {
+               struct gfs2_dinode *dinode = (struct gfs2_dinode *)bh->b_data;
+               entries = gfs2_32_to_cpu(dinode->di_entries);
+       }
+
+       if (!entries)
+               return TRUE;
+
+       do {
+               uint32_t cur_rec_len, cur_name_len;
+
+               cur_rec_len = gfs2_32_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 TRUE;
+       } while (dirent_next(dip, bh, &dent) == 0);
+
+       return FALSE;
+}
+
+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 = gfs2_16_to_cpu(leaf->lf_entries);
+       } else if (type == IS_DINODE) {
+               struct gfs2_dinode *dinode = (struct gfs2_dinode *)bh->b_data;
+               entries = gfs2_32_to_cpu(dinode->di_entries);
+       }
+
+       hash = gfs2_disk_hash(filename->name, filename->len);
+
+       do {
+               if (!dent->de_inum.no_addr) {
+                       prev = dent;
+                       continue;
+               }
+
+               if (gfs2_32_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 = gfs2_64_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, gfs2_64_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_gfs2_32(GFS2_FORMAT_DE);
+       leaf->lf_entries = cpu_to_gfs2_16(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 = gfs2_32_to_cpu(dent->de_rec_len) +
+               sizeof(struct gfs2_dinode) -
+               sizeof(struct gfs2_leaf);
+       dent->de_rec_len = cpu_to_gfs2_32(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_gfs2_64(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 = FALSE;
+       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_gfs2_32(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 - gfs2_16_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_gfs2_64(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 &&
+                   gfs2_32_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 = gfs2_16_to_cpu(nleaf->lf_entries)+1;
+                       nleaf->lf_entries = cpu_to_gfs2_16(nleaf->lf_entries);
+
+                       dirent_del(dip, obh, prev, dent);
+
+                       if (!oleaf->lf_entries)
+                               gfs2_consist_inode(dip);
+                       oleaf->lf_entries = gfs2_16_to_cpu(oleaf->lf_entries)-1;
+                       oleaf->lf_entries = cpu_to_gfs2_16(oleaf->lf_entries);
+
+                       if (!prev)
+                               prev = dent;
+
+                       moved = TRUE;
+               } 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 = gfs2_16_to_cpu(oleaf->lf_depth) + 1;
+       oleaf->lf_depth = cpu_to_gfs2_16(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 = gfs2_32_to_cpu(hash_a);
+
+       dent_b = *(struct gfs2_dirent **)b;
+       hash_b = dent_b->de_hash;
+       hash_b = gfs2_32_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 = FALSE;
+       int error = 0;
+
+       sort(darr, entries, sizeof(struct gfs2_dirent *), compare_dents, NULL);
+
+       dent_next = darr[0];
+       off_next = gfs2_32_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 = gfs2_32_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 = TRUE;
+                       } else
+                               run = FALSE;
+               } 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 = TRUE;
+       }
+
+       /* 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 = gfs2_16_to_cpu(leaf->lf_entries);
+       ln = leaf->lf_next;
+
+       while (ln) {
+               ln = gfs2_64_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 += gfs2_16_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 = gfs2_64_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 (gfs2_16_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 = gfs2_64_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_gfs2_64(bn);
+
+                               nleaf = (struct gfs2_leaf *)nbh->b_data;
+                               nleaf->lf_depth = leaf->lf_depth;
+                               nleaf->lf_dirent_format = 
cpu_to_gfs2_32(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_gfs2_32(hash);
+               dent->de_type = type;
+               memcpy((char *)(dent + 1), filename->name, filename->len);
+
+               leaf->lf_entries = gfs2_16_to_cpu(leaf->lf_entries) + 1;
+               leaf->lf_entries = cpu_to_gfs2_16(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 = gfs2_16_to_cpu(leaf->lf_entries);
+       if (!entries)
+               gfs2_consist_inode(dip);
+       entries--;
+       leaf->lf_entries = cpu_to_gfs2_16(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 = FALSE;
+       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, gfs2_64_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_gfs2_32(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 = FALSE;
+       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 = gfs2_64_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_gfs2_32(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 TRUE if an alloc is required, FALSE 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 = FALSE;
+
+       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 = TRUE;
+                               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 = TRUE;
+
+               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);
+}
+
--- a/fs/gfs2/dir.h     1970-01-01 07:30:00.000000000 +0730
+++ b/fs/gfs2/dir.h     2005-09-01 17:36:55.180135992 +0800
@@ -0,0 +1,51 @@
+/*
+ * 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.
+ */
+
+#ifndef __DIR_DOT_H__
+#define __DIR_DOT_H__
+
+/**
+ * gfs2_filldir_t - Report a directory entry to the caller of gfs2_dir_read()
+ * @opaque: opaque data used by the function
+ * @name: the name of the directory entry
+ * @length: the length of the name
+ * @offset: the entry's offset in the directory
+ * @inum: the inode number the entry points to
+ * @type: the type of inode the entry points to
+ *
+ * Returns: 0 on success, 1 if buffer full
+ */
+
+typedef int (*gfs2_filldir_t) (void *opaque,
+                             const char *name, unsigned int length,
+                             uint64_t offset,
+                             struct gfs2_inum *inum, unsigned int type);
+
+int gfs2_filecmp(struct qstr *file1, char *file2, int len_of_file2);
+int gfs2_dirent_alloc(struct gfs2_inode *dip, struct buffer_head *bh,
+                    int name_len, struct gfs2_dirent **dent_out);
+
+int gfs2_dir_search(struct gfs2_inode *dip, struct qstr *filename,
+                  struct gfs2_inum *inum, unsigned int *type);
+int gfs2_dir_add(struct gfs2_inode *dip, struct qstr *filename,
+               struct gfs2_inum *inum, unsigned int type);
+int gfs2_dir_del(struct gfs2_inode *dip, struct qstr *filename);
+int gfs2_dir_read(struct gfs2_inode *dip, uint64_t * offset, void *opaque,
+                gfs2_filldir_t filldir);
+int gfs2_dir_mvino(struct gfs2_inode *dip, struct qstr *filename,
+                 struct gfs2_inum *new_inum, unsigned int new_type);
+
+int gfs2_dir_exhash_dealloc(struct gfs2_inode *dip);
+
+int gfs2_diradd_alloc_required(struct gfs2_inode *dip, struct qstr *filename,
+                             int *alloc_required);
+
+int gfs2_get_dir_meta(struct gfs2_inode *ip, struct gfs2_user_buffer *ub);
+
+#endif /* __DIR_DOT_H__ */
-
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