linux-sg2042/fs/nilfs2/ifile.c

151 lines
4.1 KiB
C

/*
* ifile.c - NILFS inode file
*
* Copyright (C) 2006-2008 Nippon Telegraph and Telephone Corporation.
*
* 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., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
*
* Written by Amagai Yoshiji <amagai@osrg.net>.
* Revised by Ryusuke Konishi <ryusuke@osrg.net>.
*
*/
#include <linux/types.h>
#include <linux/buffer_head.h>
#include "nilfs.h"
#include "mdt.h"
#include "alloc.h"
#include "ifile.h"
/**
* nilfs_ifile_create_inode - create a new disk inode
* @ifile: ifile inode
* @out_ino: pointer to a variable to store inode number
* @out_bh: buffer_head contains newly allocated disk inode
*
* Return Value: On success, 0 is returned and the newly allocated inode
* number is stored in the place pointed by @ino, and buffer_head pointer
* that contains newly allocated disk inode structure is stored in the
* place pointed by @out_bh
* On error, one of the following negative error codes is returned.
*
* %-EIO - I/O error.
*
* %-ENOMEM - Insufficient amount of memory available.
*
* %-ENOSPC - No inode left.
*/
int nilfs_ifile_create_inode(struct inode *ifile, ino_t *out_ino,
struct buffer_head **out_bh)
{
struct nilfs_palloc_req req;
int ret;
req.pr_entry_nr = 0; /* 0 says find free inode from beginning of
a group. dull code!! */
req.pr_entry_bh = NULL;
ret = nilfs_palloc_prepare_alloc_entry(ifile, &req);
if (!ret) {
ret = nilfs_palloc_get_entry_block(ifile, req.pr_entry_nr, 1,
&req.pr_entry_bh);
if (ret < 0)
nilfs_palloc_abort_alloc_entry(ifile, &req);
}
if (ret < 0) {
brelse(req.pr_entry_bh);
return ret;
}
nilfs_palloc_commit_alloc_entry(ifile, &req);
nilfs_mdt_mark_buffer_dirty(req.pr_entry_bh);
nilfs_mdt_mark_dirty(ifile);
*out_ino = (ino_t)req.pr_entry_nr;
*out_bh = req.pr_entry_bh;
return 0;
}
/**
* nilfs_ifile_delete_inode - delete a disk inode
* @ifile: ifile inode
* @ino: inode number
*
* Return Value: On success, 0 is returned. On error, one of the following
* negative error codes is returned.
*
* %-EIO - I/O error.
*
* %-ENOMEM - Insufficient amount of memory available.
*
* %-ENOENT - The inode number @ino have not been allocated.
*/
int nilfs_ifile_delete_inode(struct inode *ifile, ino_t ino)
{
struct nilfs_palloc_req req = {
.pr_entry_nr = ino, .pr_entry_bh = NULL
};
struct nilfs_inode *raw_inode;
void *kaddr;
int ret;
ret = nilfs_palloc_prepare_free_entry(ifile, &req);
if (!ret) {
ret = nilfs_palloc_get_entry_block(ifile, req.pr_entry_nr, 0,
&req.pr_entry_bh);
if (ret < 0)
nilfs_palloc_abort_free_entry(ifile, &req);
}
if (ret < 0) {
brelse(req.pr_entry_bh);
return ret;
}
kaddr = kmap_atomic(req.pr_entry_bh->b_page, KM_USER0);
raw_inode = nilfs_palloc_block_get_entry(ifile, req.pr_entry_nr,
req.pr_entry_bh, kaddr);
raw_inode->i_flags = 0;
kunmap_atomic(kaddr, KM_USER0);
nilfs_mdt_mark_buffer_dirty(req.pr_entry_bh);
brelse(req.pr_entry_bh);
nilfs_palloc_commit_free_entry(ifile, &req);
return 0;
}
int nilfs_ifile_get_inode_block(struct inode *ifile, ino_t ino,
struct buffer_head **out_bh)
{
struct super_block *sb = ifile->i_sb;
int err;
if (unlikely(!NILFS_VALID_INODE(sb, ino))) {
nilfs_error(sb, __func__, "bad inode number: %lu",
(unsigned long) ino);
return -EINVAL;
}
err = nilfs_palloc_get_entry_block(ifile, ino, 0, out_bh);
if (unlikely(err)) {
if (err == -EINVAL)
nilfs_error(sb, __func__, "ifile is broken");
else
nilfs_warning(sb, __func__,
"unable to read inode: %lu",
(unsigned long) ino);
}
return err;
}