/* -*- mode: c; c-basic-offset: 8; -*-
* vim: noexpandtab sw=8 ts=8 sts=0:
*
* dir.c
*
* Creates, reads, walks and deletes directory-nodes
*
* Copyright (C) 2002, 2004 Oracle. All rights reserved.
*
* Portions of this code from linux/fs/ext3/dir.c
*
* Copyright (C) 1992, 1993, 1994, 1995
* Remy Card (card@masi.ibp.fr)
* Laboratoire MASI - Institut Blaise pascal
* Universite Pierre et Marie Curie (Paris VI)
*
* from
*
* linux/fs/minix/dir.c
*
* Copyright (C) 1991, 1992 Linux Torvalds
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public
* License as published by the Free Software Foundation; either
* version 2 of the License, or (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* General Public License for more details.
*
* You should have received a copy of the GNU General Public
* License along with this program; if not, write to the
* Free Software Foundation, Inc., 59 Temple Place - Suite 330,
* Boston, MA 021110-1307, USA.
*/
#include <linux/fs.h>
#include <linux/types.h>
#include <linux/slab.h>
#include <linux/highmem.h>
#define MLOG_MASK_PREFIX ML_NAMEI
#include <cluster/masklog.h>
#include "ocfs2.h"
#include "alloc.h"
#include "dir.h"
#include "dlmglue.h"
#include "extent_map.h"
#include "file.h"
#include "inode.h"
#include "journal.h"
#include "namei.h"
#include "suballoc.h"
#include "super.h"
#include "uptodate.h"
#include "buffer_head_io.h"
#define NAMEI_RA_CHUNKS 2
#define NAMEI_RA_BLOCKS 4
#define NAMEI_RA_SIZE (NAMEI_RA_CHUNKS * NAMEI_RA_BLOCKS)
#define NAMEI_RA_INDEX(c,b) (((c) * NAMEI_RA_BLOCKS) + (b))
static unsigned char ocfs2_filetype_table[] = {
DT_UNKNOWN, DT_REG, DT_DIR, DT_CHR, DT_BLK, DT_FIFO, DT_SOCK, DT_LNK
};
static int ocfs2_extend_dir(struct ocfs2_super *osb,
struct inode *dir,
struct buffer_head *parent_fe_bh,
struct buffer_head **new_de_bh);
static int ocfs2_do_extend_dir(struct super_block *sb,
handle_t *handle,
struct inode *dir,
struct buffer_head *parent_fe_bh,
struct ocfs2_alloc_context *data_ac,
struct ocfs2_alloc_context *meta_ac,
struct buffer_head **new_bh);
static int ocfs2_check_dir_entry(struct inode * dir,
struct ocfs2_dir_entry * de,
struct buffer_head * bh,
unsigned long offset)
{
const char *error_msg = NULL;
const int rlen = le16_to_cpu(de->rec_len);
if (rlen < OCFS2_DIR_REC_LEN(1))
error_msg = "rec_len is smaller than minimal";
else if (rlen % 4 != 0)
error_msg = "rec_len % 4 != 0";
else if (rlen < OCFS2_DIR_REC_LEN(de->name_len))
error_msg = "rec_len is too small for name_len";
else if (((char *) de - bh->b_data) + rlen > dir->i_sb->s_blocksize)
error_msg = "directory entry across blocks";
if (error_msg != NULL)
mlog(ML_ERROR, "bad entry in directory #%llu: %s - "
"offset=%lu, inode=%llu, rec_len=%d, name_len=%d\n",
(unsigned long long)OCFS2_I(dir)->ip_blkno, error_msg,
offset, (unsigned long long)le64_to_cpu(de->inode), rlen,
de->name_len);
return error_msg == NULL ? 1 : 0;
}
static inline int ocfs2_match(int len,
const char * const name,
struct ocfs2_dir_entry *de)
{
if (len != de->name_len)
return 0;
if (!de->inode)
return 0;
return !memcmp(name, de->name, len);
}
/*
* Returns 0 if not found, -1 on failure, and 1 on success
*/
static int inline ocfs2_search_dirblock(struct buffer_head *bh,
struct inode *dir,
const char *name, int namelen,
unsigned long offset,
struct ocfs2_dir_entry **res_dir)
{
struct ocfs2_dir_entry *de;
char *dlimit, *de_buf;
int de_len;
int ret = 0;
mlog_entry_void();
de_buf = bh->b_data;
dlimit = de_buf + dir->i_sb->s_blocksize;
while (de_buf < dlimit) {
/* this code is executed quadratically often */
/* do minimal checking `by hand' */
de = (struct ocfs2_dir_entry *) de_buf;
if (de_buf + namelen <= dlimit &&
ocfs2_match(namelen, name, de)) {
/* found a match - just to be sure, do a full check */
if (!ocfs2_check_dir_entry(dir, de, bh, offset)) {
ret = -1;
goto bail;
}
*res_dir = de;
ret = 1;
goto bail;
}
/* prevent looping on a bad block */
de_len = le16_to_cpu(de->rec_len);
if (de_len <= 0) {
ret = -1;
goto bail;
}
de_buf += de_len;
offset += de_len;
}
bail:
mlog_exit(ret);
return ret;
}
struct buffer_head *ocfs2_find_entry(const char *name, int namelen,
struct inode *dir,
struct ocfs2_dir_entry **res_dir)
{
struct super_block *sb;
struct buffer_head *bh_use[NAMEI_RA_SIZE];
struct buffer_head *bh, *ret = NULL;
unsigned long start, block, b;
int ra_max = 0; /* Number of bh's in the readahead
buffer, bh_use[] */
int ra_ptr = 0; /* Current index into readahead
buffer */
int num = 0;
int nblocks, i, err;
mlog_entry_void();
*res_dir = NULL;
sb = dir->i_sb;
nblocks = i_size_read(dir) >> sb->s_blocksize_bits;
start = OCFS2_I(dir)->ip_dir_start_lookup;
if (start >= nblocks)
start = 0;
block = start;
restart:
do {
/*
* We deal with the read-ahead logic here.
*/
if (ra_ptr >= ra_max) {
/* Refill the readahead buffer */
ra_ptr = 0;
b = block;
for (ra_max = 0; ra_max < NAMEI_RA_SIZE; ra_max++) {
/*
* Terminate if we reach the end of the
* directory and must wrap, or if our
* search has finished at this block.
*/
if (b >= nblocks || (num && block == start)) {
bh_use[ra_max] = NULL;
break;
}
num++;
bh = ocfs2_bread(dir, b++, &err, 1);
bh_use[ra_max] = bh;
}
}
if ((bh = bh_use[ra_ptr++]) == NULL)
goto next;
wait_on_buffer(bh);
if (!buffer_uptodate(bh)) {
/* read error, skip block & hope for the best */
ocfs2_error(dir->i_sb, "reading directory %llu, "
"offset %lu\n",
(unsigned long long)OCFS2_I(dir)->ip_blkno,
block);
brelse(bh);
goto next;
}
i = ocfs2_search_dirblock(bh, dir, name, namelen,
block << sb->s_blocksize_bits,
res_dir);
if (i == 1) {
OCFS2_I(dir)->ip_dir_start_lookup = block;
ret = bh;
goto cleanup_and_exit;
} else {
brelse(bh);
if (i < 0)
goto cleanup_and_exit;
}
next:
if (++block >= nblocks)
block = 0;
} while (block != start);
/*
* If the directory has grown while we were searching, then
* search the last part of the directory before giving up.
*/
block = nblocks;
nblocks = i_size_read(dir) >> sb->s_blocksize_bits;
if (block < nblocks) {
start = 0;
goto restart;
}
cleanup_and_exit:
/* Clean up the read-ahead blocks */
for (; ra_ptr < ra_max; ra_ptr++)
brelse(bh_use[ra_ptr]);
mlog_exit_ptr(ret);
return ret;
}
/*
* ocfs2_delete_entry deletes a directory entry by merging it with the
* previous entry
*/
int ocfs2_delete_entry(handle_t *handle,
struct inode *dir,
struct ocfs2_dir_entry *de_del,
struct buffer_head *bh)
{
struct ocfs2_dir_entry *de, *pde;
int i, status = -ENOENT;
mlog_entry("(0x%p, 0x%p, 0x%p, 0x%p)\n", handle, dir, de_del, bh);
i = 0;
pde = NULL;
de = (struct ocfs2_dir_entry *) bh->b_data;
while (i < bh->b_size) {
if (!ocfs2_check_dir_entry(dir, de, bh, i)) {
status = -EIO;
mlog_errno(status);
goto bail;
}
if (de == de_del) {
status = ocfs2_journal_access(handle, dir, bh,
OCFS2_JOURNAL_ACCESS_WRITE);
if (status < 0) {
status = -EIO;
mlog_errno(status);
goto bail;
}
if (pde)
pde->rec_len =
cpu_to_le16(le16_to_cpu(pde->rec_len) +
le16_to_cpu(de->rec_len));
else
de->inode = 0;
dir->i_version++;
status = ocfs2_journal_dirty(handle, bh);
goto bail;
}
i += le16_to_cpu(de->rec_len);
pde = de;
de = (struct ocfs2_dir_entry *)((char *)de + le16_to_cpu(de->rec_len));
}
bail:
mlog_exit(status);
return status;
}
/* we don't always have a dentry for what we want to add, so people
* like orphan dir can call this instead.
*
* If you pass me insert_bh, I'll skip the search of the other dir
* blocks and put the record in there.
*/
int __ocfs2_add_entry(handle_t *handle,
struct inode *dir,
const char *name, int namelen,
struct inode *inode, u64 blkno,
struct buffer_head *parent_fe_bh,
struct buffer_head *insert_bh)
{
unsigned long offset;
unsigned short rec_len;
struct ocfs2_dir_entry *de, *de1;
struct super_block *sb;
int retval, status;
mlog_entry_void();
sb = dir->i_sb;
if (!namelen)
return -EINVAL;
rec_len = OCFS2_DIR_REC_LEN(namelen);
offset = 0;
de = (struct ocfs2_dir_entry *) insert_bh->b_data;
while (1) {
BUG_ON((char *)de >= sb->s_blocksize + insert_bh->b_data);
/* These checks should've already been passed by the
* prepare function, but I guess we can leave them
* here anyway. */
if (!ocfs2_check_dir_entry(dir, de, insert_bh, offset)) {
retval = -ENOENT;
goto bail;
}
if (ocfs2_match(namelen, name, de)) {
retval = -EEXIST;
goto bail;
}
if (((le64_to_cpu(de->inode) == 0) &&
(le16_to_cpu(de->rec_len) >= rec_len)) ||
(le16_to_cpu(de->rec_len) >=
(OCFS2_DIR_REC_LEN(de->name_len) + rec_len))) {
dir->i_mtime = dir->i_ctime = CURRENT_TIME;
retval = ocfs2_mark_inode_dirty(handle, dir, parent_fe_bh);
if (retval < 0) {
mlog_errno(retval);
goto bail;
}
status = ocfs2_journal_access(handle, dir, insert_bh,
OCFS2_JOURNAL_ACCESS_WRITE);
/* By now the buffer is marked for journaling */
offset += le16_to_cpu(de->rec_len);
if (le64_to_cpu(de->inode)) {
de1 = (struct ocfs2_dir_entry *)((char *) de +
OCFS2_DIR_REC_LEN(de->name_len));
de1->rec_len =
cpu_to_le16(le16_to_cpu(de->rec_len) -
OCFS2_DIR_REC_LEN(de->name_len));
de->rec_len = cpu_to_le16(OCFS2_DIR_REC_LEN(de->name_len));
de = de1;
}
de->file_type = OCFS2_FT_UNKNOWN;
if (blkno) {
de->inode = cpu_to_le64(blkno);
ocfs2_set_de_type(de, inode->i_mode);
} else
de->inode = 0;
de->name_len = namelen;
memcpy(de->name, name, namelen);
dir->i_version++;
status = ocfs2_journal_dirty(handle, insert_bh);
retval = 0;
goto bail;
}
offset += le16_to_cpu(de->rec_len);
de = (struct ocfs2_dir_entry *) ((char *) de + le16_to_cpu(de->rec_len));
}
/* when you think about it, the assert above should prevent us
* from ever getting here. */
retval = -ENOSPC;
bail:
mlog_exit(retval);
return retval;
}
static int ocfs2_dir_foreach_blk(struct inode *inode, unsigned long *f_version,
loff_t *f_pos, void *priv, filldir_t filldir)
{
int error = 0;
unsigned long offset, blk, last_ra_blk = 0;
int i, stored;
struct buffer_head * bh, * tmp;
struct ocfs2_dir_entry * de;
int err;
struct super_block * sb = inode->i_sb;
unsigned int ra_sectors = 16;
stored = 0;
bh = NULL;
offset = (*f_pos) & (sb->s_blocksize - 1);
while (!error && !stored && *f_pos < i_size_read(inode)) {
blk = (*f_pos) >> sb->s_blocksize_bits;
bh = ocfs2_bread(inode, blk, &err, 0);
if (!bh) {
mlog(ML_ERROR,
"directory #%llu contains a hole at offset %lld\n",
(unsigned long long)OCFS2_I(inode)->ip_blkno,
*f_pos);
*f_pos += sb->s_blocksize - offset;
continue;
}
/* The idea here is to begin with 8k read-ahead and to stay
* 4k ahead of our current position.
*
* TODO: Use the pagecache for this. We just need to
* make sure it's cluster-safe... */
if (!last_ra_blk
|| (((last_ra_blk - blk) << 9) <= (ra_sectors / 2))) {
for (i = ra_sectors >> (sb->s_blocksize_bits - 9);
i > 0; i--) {
tmp = ocfs2_bread(inode, ++blk, &err, 1);
if (tmp)
brelse(tmp);
}
last_ra_blk = blk;
ra_sectors = 8;
}
revalidate:
/* If the dir block has changed since the last call to
* readdir(2), then we might be pointing to an invalid
* dirent right now. Scan from the start of the block
* to make sure. */
if (*f_version != inode->i_version) {
for (i = 0; i < sb->s_blocksize && i < offset; ) {
de = (struct ocfs2_dir_entry *) (bh->b_data + i);
/* It's too expensive to do a full
* dirent test each time round this
* loop, but we do have to test at
* least that it is non-zero. A
* failure will be detected in the
* dirent test below. */
if (le16_to_cpu(de->rec_len) <
OCFS2_DIR_REC_LEN(1))
break;
i += le16_to_cpu(de->rec_len);
}
offset = i;
*f_pos = ((*f_pos) & ~(sb->s_blocksize - 1))
| offset;
*f_version = inode->i_version;
}
while (!error && *f_pos < i_size_read(inode)
&& offset < sb->s_blocksize) {
de = (struct ocfs2_dir_entry *) (bh->b_data + offset);
if (!ocfs2_check_dir_entry(inode, de, bh, offset)) {
/* On error, skip the f_pos to the
next block. */
*f_pos = ((*f_pos) | (sb->s_blocksize - 1)) + 1;
brelse(bh);
goto out;
}
offset += le16_to_cpu(de->rec_len);
if (le64_to_cpu(de->inode)) {
/* We might block in the next section
* if the data destination is
* currently swapped out. So, use a
* version stamp to detect whether or
* not the directory has been modified
* during the copy operation.
*/
unsigned long version = *f_version;
unsigned char d_type = DT_UNKNOWN;
if (de->file_type < OCFS2_FT_MAX)
d_type = ocfs2_filetype_table[de->file_type];
error = filldir(priv, de->name,
de->name_len,
*f_pos,
le64_to_cpu(de->inode),
d_type);
if (error)
break;
if (version != *f_version)
goto revalidate;
stored ++;
}
*f_pos += le16_to_cpu(de->rec_len);
}
offset = 0;
brelse(bh);
}
stored = 0;
out:
return stored;
}
/*
* This is intended to be called from inside other kernel functions,
* so we fake some arguments.
*/
int ocfs2_dir_foreach(struct inode *inode, loff_t *f_pos, void *priv,
filldir_t filldir)
{
int ret = 0;
unsigned long version = inode->i_version;
while (*f_pos < i_size_read(inode)) {
ret = ocfs2_dir_foreach_blk(inode, &version, f_pos, priv,
filldir);
if (ret)
break;
}
return 0;
}
/*
* ocfs2_readdir()
*
*/
int ocfs2_readdir(struct file * filp, void * dirent, filldir_t filldir)
{
int error = 0;
struct inode *inode = filp->f_path.dentry->d_inode;
int lock_level = 0;
mlog_entry("dirino=%llu\n",
(unsigned long long)OCFS2_I(inode)->ip_blkno);
error = ocfs2_meta_lock_atime(inode, filp->f_vfsmnt, &lock_level);
if (lock_level && error >= 0) {
/* We release EX lock which used to update atime
* and get PR lock again to reduce contention
* on commonly accessed directories. */
ocfs2_meta_unlock(inode, 1);
lock_level = 0;
error = ocfs2_meta_lock(inode, NULL, 0);
}
if (error < 0) {
if (error != -ENOENT)
mlog_errno(error);
/* we haven't got any yet, so propagate the error. */
goto bail_nolock;
}
error = ocfs2_dir_foreach_blk(inode, &filp->f_version, &filp->f_pos,
dirent, filldir);
ocfs2_meta_unlock(inode, lock_level);
bail_nolock:
mlog_exit(error);
return error;
}
/*
* NOTE: this should always be called with parent dir i_mutex taken.
*/
int ocfs2_find_files_on_disk(const char *name,
int namelen,
u64 *blkno,
struct inode *inode,
struct buffer_head **dirent_bh,
struct ocfs2_dir_entry **dirent)
{
int status = -ENOENT;
mlog_entry("(name=%.*s, blkno=%p, inode=%p, dirent_bh=%p, dirent=%p)\n",
namelen, name, blkno, inode, dirent_bh, dirent);
*dirent_bh = ocfs2_find_entry(name, namelen, inode, dirent);
if (!*dirent_bh || !*dirent) {
status = -ENOENT;
goto leave;
}
*blkno = le64_to_cpu((*dirent)->inode);
status = 0;
leave:
if (status < 0) {
*dirent = NULL;
if (*dirent_bh) {
brelse(*dirent_bh);
*dirent_bh = NULL;
}
}
mlog_exit(status);
return status;
}
/*
* Convenience function for callers which just want the block number
* mapped to a name and don't require the full dirent info, etc.
*/
int ocfs2_lookup_ino_from_name(struct inode *dir, const char *name,
int namelen, u64 *blkno)
{
int ret;
struct buffer_head *bh = NULL;
struct ocfs2_dir_entry *dirent = NULL;
ret = ocfs2_find_files_on_disk(name, namelen, blkno, dir, &bh, &dirent);
brelse(bh);
return ret;
}
/* Check for a name within a directory.
*
* Return 0 if the name does not exist
* Return -EEXIST if the directory contains the name
*
* Callers should have i_mutex + a cluster lock on dir
*/
int ocfs2_check_dir_for_entry(struct inode *dir,
const char *name,
int namelen)
{
int ret;
struct buffer_head *dirent_bh = NULL;
struct ocfs2_dir_entry *dirent = NULL;
mlog_entry("dir %llu, name '%.*s'\n",
(unsigned long long)OCFS2_I(dir)->ip_blkno, namelen, name);
ret = -EEXIST;
dirent_bh = ocfs2_find_entry(name, namelen, dir, &dirent);
if (dirent_bh)
goto bail;
ret = 0;
bail:
if (dirent_bh)
brelse(dirent_bh);
mlog_exit(ret);
return ret;
}
struct ocfs2_empty_dir_priv {
unsigned seen_dot;
unsigned seen_dot_dot;
unsigned seen_other;
};
static int ocfs2_empty_dir_filldir(void *priv, const char *name, int name_len,
loff_t pos, u64 ino, unsigned type)
{
struct ocfs2_empty_dir_priv *p = priv;
/*
* Check the positions of "." and ".." records to be sure
* they're in the correct place.
*/
if (name_len == 1 && !strncmp(".", name, 1) && pos == 0) {
p->seen_dot = 1;
return 0;
}
if (name_len == 2 && !strncmp("..", name, 2) &&
pos == OCFS2_DIR_REC_LEN(1)) {
p->seen_dot_dot = 1;
return 0;
}
p->seen_other = 1;
return 1;
}
/*
* routine to check that the specified directory is empty (for rmdir)
*
* Returns 1 if dir is empty, zero otherwise.
*/
int ocfs2_empty_dir(struct inode *inode)
{
int ret;
loff_t start = 0;
struct ocfs2_empty_dir_priv priv;
memset(&priv, 0, sizeof(priv));
ret = ocfs2_dir_foreach(inode, &start, &priv, ocfs2_empty_dir_filldir);
if (ret)
mlog_errno(ret);
if (!priv.seen_dot || !priv.seen_dot_dot) {
mlog(ML_ERROR, "bad directory (dir #%llu) - no `.' or `..'\n",
(unsigned long long)OCFS2_I(inode)->ip_blkno);
/*
* XXX: Is it really safe to allow an unlink to continue?
*/
return 1;
}
return !priv.seen_other;
}
int ocfs2_fill_new_dir(struct ocfs2_super *osb,
handle_t *handle,
struct inode *parent,
struct inode *inode,
struct buffer_head *fe_bh,
struct ocfs2_alloc_context *data_ac)
{
int status;
struct buffer_head *new_bh = NULL;
struct ocfs2_dir_entry *de = NULL;
mlog_entry_void();
status = ocfs2_do_extend_dir(osb->sb, handle, inode, fe_bh,
data_ac, NULL, &new_bh);
if (status < 0) {
mlog_errno(status);
goto bail;
}
ocfs2_set_new_buffer_uptodate(inode, new_bh);
status = ocfs2_journal_access(handle, inode, new_bh,
OCFS2_JOURNAL_ACCESS_CREATE);
if (status < 0) {
mlog_errno(status);
goto bail;
}
memset(new_bh->b_data, 0, osb->sb->s_blocksize);
de = (struct ocfs2_dir_entry *) new_bh->b_data;
de->inode = cpu_to_le64(OCFS2_I(inode)->ip_blkno);
de->name_len = 1;
de->rec_len =
cpu_to_le16(OCFS2_DIR_REC_LEN(de->name_len));
strcpy(de->name, ".");
ocfs2_set_de_type(de, S_IFDIR);
de = (struct ocfs2_dir_entry *) ((char *)de + le16_to_cpu(de->rec_len));
de->inode = cpu_to_le64(OCFS2_I(parent)->ip_blkno);
de->rec_len = cpu_to_le16(inode->i_sb->s_blocksize -
OCFS2_DIR_REC_LEN(1));
de->name_len = 2;
strcpy(de->name, "..");
ocfs2_set_de_type(de, S_IFDIR);
status = ocfs2_journal_dirty(handle, new_bh);
if (status < 0) {
mlog_errno(status);
goto bail;
}
i_size_write(inode, inode->i_sb->s_blocksize);
inode->i_nlink = 2;
inode->i_blocks = ocfs2_inode_sector_count(inode);
status = ocfs2_mark_inode_dirty(handle, inode, fe_bh);
if (status < 0) {
mlog_errno(status);
goto bail;
}
status = 0;
bail:
if (new_bh)
brelse(new_bh);
mlog_exit(status);
return status;
}
/* returns a bh of the 1st new block in the allocation. */
static int ocfs2_do_extend_dir(struct super_block *sb,
handle_t *handle,
struct inode *dir,
struct buffer_head *parent_fe_bh,
struct ocfs2_alloc_context *data_ac,
struct ocfs2_alloc_context *meta_ac,
struct buffer_head **new_bh)
{
int status;
int extend;
u64 p_blkno, v_blkno;
spin_lock(&OCFS2_I(dir)->ip_lock);
extend = (i_size_read(dir) == ocfs2_clusters_to_bytes(sb, OCFS2_I(dir)->ip_clusters));
spin_unlock(&OCFS2_I(dir)->ip_lock);
if (extend) {
u32 offset = OCFS2_I(dir)->ip_clusters;
status = ocfs2_do_extend_allocation(OCFS2_SB(sb), dir, &offset,
1, 0, parent_fe_bh, handle,
data_ac, meta_ac, NULL);
BUG_ON(status == -EAGAIN);
if (status < 0) {
mlog_errno(status);
goto bail;
}
}
v_blkno = ocfs2_blocks_for_bytes(sb, i_size_read(dir));
status = ocfs2_extent_map_get_blocks(dir, v_blkno, &p_blkno, NULL, NULL);
if (status < 0) {
mlog_errno(status);
goto bail;
}
*new_bh = sb_getblk(sb, p_blkno);
if (!*new_bh) {
status = -EIO;
mlog_errno(status);
goto bail;
}
status = 0;
bail:
mlog_exit(status);
return status;
}
/* assumes you already have a cluster lock on the directory. */
static int ocfs2_extend_dir(struct ocfs2_super *osb,
struct inode *dir,
struct buffer_head *parent_fe_bh,
struct buffer_head **new_de_bh)
{
int status = 0;
int credits, num_free_extents, drop_alloc_sem = 0;
loff_t dir_i_size;
struct ocfs2_dinode *fe = (struct ocfs2_dinode *) parent_fe_bh->b_data;
struct ocfs2_alloc_context *data_ac = NULL;
struct ocfs2_alloc_context *meta_ac = NULL;
handle_t *handle = NULL;
struct buffer_head *new_bh = NULL;
struct ocfs2_dir_entry * de;
struct super_block *sb = osb->sb;
mlog_entry_void();
dir_i_size = i_size_read(dir);
mlog(0, "extending dir %llu (i_size = %lld)\n",
(unsigned long long)OCFS2_I(dir)->ip_blkno, dir_i_size);
/* dir->i_size is always block aligned. */
spin_lock(&OCFS2_I(dir)->ip_lock);
if (dir_i_size == ocfs2_clusters_to_bytes(sb, OCFS2_I(dir)->ip_clusters)) {
spin_unlock(&OCFS2_I(dir)->ip_lock);
num_free_extents = ocfs2_num_free_extents(osb, dir, fe);
if (num_free_extents < 0) {
status = num_free_extents;
mlog_errno(status);
goto bail;
}
if (!num_free_extents) {
status = ocfs2_reserve_new_metadata(osb, fe, &meta_ac);
if (status < 0) {
if (status != -ENOSPC)
mlog_errno(status);
goto bail;
}
}
status = ocfs2_reserve_clusters(osb, 1, &data_ac);
if (status < 0) {
if (status != -ENOSPC)
mlog_errno(status);
goto bail;
}
credits = ocfs2_calc_extend_credits(sb, fe, 1);
} else {
spin_unlock(&OCFS2_I(dir)->ip_lock);
credits = OCFS2_SIMPLE_DIR_EXTEND_CREDITS;
}
down_write(&OCFS2_I(dir)->ip_alloc_sem);
drop_alloc_sem = 1;
handle = ocfs2_start_trans(osb, credits);
if (IS_ERR(handle)) {
status = PTR_ERR(handle);
handle = NULL;
mlog_errno(status);
goto bail;
}
status = ocfs2_do_extend_dir(osb->sb, handle, dir, parent_fe_bh,
data_ac, meta_ac, &new_bh);
if (status < 0) {
mlog_errno(status);
goto bail;
}
ocfs2_set_new_buffer_uptodate(dir, new_bh);
status = ocfs2_journal_access(handle, dir, new_bh,
OCFS2_JOURNAL_ACCESS_CREATE);
if (status < 0) {
mlog_errno(status);
goto bail;
}
memset(new_bh->b_data, 0, sb->s_blocksize);
de = (struct ocfs2_dir_entry *) new_bh->b_data;
de->inode = 0;
de->rec_len = cpu_to_le16(sb->s_blocksize);
status = ocfs2_journal_dirty(handle, new_bh);
if (status < 0) {
mlog_errno(status);
goto bail;
}
dir_i_size += dir->i_sb->s_blocksize;
i_size_write(dir, dir_i_size);
dir->i_blocks = ocfs2_inode_sector_count(dir);
status = ocfs2_mark_inode_dirty(handle, dir, parent_fe_bh);
if (status < 0) {
mlog_errno(status);
goto bail;
}
*new_de_bh = new_bh;
get_bh(*new_de_bh);
bail:
if (drop_alloc_sem)
up_write(&OCFS2_I(dir)->ip_alloc_sem);
if (handle)
ocfs2_commit_trans(osb, handle);
if (data_ac)
ocfs2_free_alloc_context(data_ac);
if (meta_ac)
ocfs2_free_alloc_context(meta_ac);
if (new_bh)
brelse(new_bh);
mlog_exit(status);
return status;
}
/*
* Search the dir for a good spot, extending it if necessary. The
* block containing an appropriate record is returned in ret_de_bh.
*/
int ocfs2_prepare_dir_for_insert(struct ocfs2_super *osb,
struct inode *dir,
struct buffer_head *parent_fe_bh,
const char *name,
int namelen,
struct buffer_head **ret_de_bh)
{
unsigned long offset;
struct buffer_head * bh = NULL;
unsigned short rec_len;
struct ocfs2_dinode *fe;
struct ocfs2_dir_entry *de;
struct super_block *sb;
int status;
mlog_entry_void();
mlog(0, "getting ready to insert namelen %d into dir %llu\n",
namelen, (unsigned long long)OCFS2_I(dir)->ip_blkno);
BUG_ON(!S_ISDIR(dir->i_mode));
fe = (struct ocfs2_dinode *) parent_fe_bh->b_data;
BUG_ON(le64_to_cpu(fe->i_size) != i_size_read(dir));
sb = dir->i_sb;
if (!namelen) {
status = -EINVAL;
mlog_errno(status);
goto bail;
}
bh = ocfs2_bread(dir, 0, &status, 0);
if (!bh) {
mlog_errno(status);
goto bail;
}
rec_len = OCFS2_DIR_REC_LEN(namelen);
offset = 0;
de = (struct ocfs2_dir_entry *) bh->b_data;
while (1) {
if ((char *)de >= sb->s_blocksize + bh->b_data) {
brelse(bh);
bh = NULL;
if (i_size_read(dir) <= offset) {
status = ocfs2_extend_dir(osb,
dir,
parent_fe_bh,
&bh);
if (status < 0) {
mlog_errno(status);
goto bail;
}
BUG_ON(!bh);
*ret_de_bh = bh;
get_bh(*ret_de_bh);
goto bail;
}
bh = ocfs2_bread(dir,
offset >> sb->s_blocksize_bits,
&status,
0);
if (!bh) {
mlog_errno(status);
goto bail;
}
/* move to next block */
de = (struct ocfs2_dir_entry *) bh->b_data;
}
if (!ocfs2_check_dir_entry(dir, de, bh, offset)) {
status = -ENOENT;
goto bail;
}
if (ocfs2_match(namelen, name, de)) {
status = -EEXIST;
goto bail;
}
if (((le64_to_cpu(de->inode) == 0) &&
(le16_to_cpu(de->rec_len) >= rec_len)) ||
(le16_to_cpu(de->rec_len) >=
(OCFS2_DIR_REC_LEN(de->name_len) + rec_len))) {
/* Ok, we found a spot. Return this bh and let
* the caller actually fill it in. */
*ret_de_bh = bh;
get_bh(*ret_de_bh);
status = 0;
goto bail;
}
offset += le16_to_cpu(de->rec_len);
de = (struct ocfs2_dir_entry *)((char *) de + le16_to_cpu(de->rec_len));
}
status = 0;
bail:
if (bh)
brelse(bh);
mlog_exit(status);
return status;
}
