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    Subject[PATCH 06/16] GFS: directories
    Code that handles directory operations.

    Signed-off-by: Ken Preslan <ken@preslan.org>
    Signed-off-by: David Teigland <teigland@redhat.com>

    ---

    fs/gfs2/dir.c | 2157 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
    fs/gfs2/dir.h | 51 +
    2 files changed, 2208 insertions(+)

    --- a/fs/gfs2/dir.c 1969-12-31 17:00:00.000000000 -0700
    +++ b/fs/gfs2/dir.c 2005-10-10 11:28:49.154809087 -0500
    @@ -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 (le16_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 = le32_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 + le32_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 = le32_to_cpu(prev->de_rec_len);
    + cur_rec_len = le32_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_le32(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 = le16_to_cpu(leaf->lf_entries);
    + offset = sizeof(struct gfs2_leaf);
    + } else {
    + struct gfs2_dinode *dinode = (struct gfs2_dinode *)bh->b_data;
    + entries = le32_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_le32(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 = le32_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_le32(new->de_rec_len);
    + new->de_name_len = name_len;
    +
    + dent->de_rec_len = cur_rec_len - le32_to_cpu(new->de_rec_len);
    + dent->de_rec_len = cpu_to_le32(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 = le16_to_cpu(leaf->lf_entries);
    + } else {
    + struct gfs2_dinode *dinode = (struct gfs2_dinode *)bh->b_data;
    + entries = le32_to_cpu(dinode->di_entries);
    + }
    +
    + if (!entries)
    + return 1;
    +
    + do {
    + uint32_t cur_rec_len, cur_name_len;
    +
    + cur_rec_len = le32_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 = le16_to_cpu(leaf->lf_entries);
    + } else if (type == IS_DINODE) {
    + struct gfs2_dinode *dinode = (struct gfs2_dinode *)bh->b_data;
    + entries = le32_to_cpu(dinode->di_entries);
    + }
    +
    + hash = gfs2_disk_hash(filename->name, filename->len);
    +
    + do {
    + if (!dent->de_inum.no_addr) {
    + prev = dent;
    + continue;
    + }
    +
    + if (le32_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 = le64_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, le64_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_le32(GFS2_FORMAT_DE);
    + leaf->lf_entries = cpu_to_le16(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 = le32_to_cpu(dent->de_rec_len) +
    + sizeof(struct gfs2_dinode) -
    + sizeof(struct gfs2_leaf);
    + dent->de_rec_len = cpu_to_le32(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_le64(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_le32(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 - le16_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_le64(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 &&
    + le32_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 = le16_to_cpu(nleaf->lf_entries)+1;
    + nleaf->lf_entries = cpu_to_le16(nleaf->lf_entries);
    +
    + dirent_del(dip, obh, prev, dent);
    +
    + if (!oleaf->lf_entries)
    + gfs2_consist_inode(dip);
    + oleaf->lf_entries = le16_to_cpu(oleaf->lf_entries)-1;
    + oleaf->lf_entries = cpu_to_le16(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 = le16_to_cpu(oleaf->lf_depth) + 1;
    + oleaf->lf_depth = cpu_to_le16(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 = le32_to_cpu(hash_a);
    +
    + dent_b = *(struct gfs2_dirent **)b;
    + hash_b = dent_b->de_hash;
    + hash_b = le32_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 = le32_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 = le32_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 = le16_to_cpu(leaf->lf_entries);
    + ln = leaf->lf_next;
    +
    + while (ln) {
    + ln = le64_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 += le16_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 = le64_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 (le16_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 = le64_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_le64(bn);
    +
    + nleaf = (struct gfs2_leaf *)nbh->b_data;
    + nleaf->lf_depth = leaf->lf_depth;
    + nleaf->lf_dirent_format = cpu_to_le32(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_le32(hash);
    + dent->de_type = type;
    + memcpy((char *)(dent + 1), filename->name, filename->len);
    +
    + leaf->lf_entries = le16_to_cpu(leaf->lf_entries) + 1;
    + leaf->lf_entries = cpu_to_le16(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 = le16_to_cpu(leaf->lf_entries);
    + if (!entries)
    + gfs2_consist_inode(dip);
    + entries--;
    + leaf->lf_entries = cpu_to_le16(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, le64_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_le32(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 = le64_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_le32(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);
    +}
    +
    --- a/fs/gfs2/dir.h 1969-12-31 17:00:00.000000000 -0700
    +++ b/fs/gfs2/dir.h 2005-10-10 11:28:49.154809087 -0500
    @@ -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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