original development tree for Linux kernel GTP module; now long in mainline.
You can not select more than 25 topics Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
 
 
 
 

227 lines
5.9 KiB

/*
* 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"
/**
* struct nilfs_ifile_info - on-memory private data of ifile
* @mi: on-memory private data of metadata file
* @palloc_cache: persistent object allocator cache of ifile
*/
struct nilfs_ifile_info {
struct nilfs_mdt_info mi;
struct nilfs_palloc_cache palloc_cache;
};
static inline struct nilfs_ifile_info *NILFS_IFILE_I(struct inode *ifile)
{
return (struct nilfs_ifile_info *)NILFS_MDT(ifile);
}
/**
* 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);
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);
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);
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))
nilfs_warning(sb, __func__, "unable to read inode: %lu",
(unsigned long) ino);
return err;
}
/**
* nilfs_ifile_count_free_inodes - calculate free inodes count
* @ifile: ifile inode
* @nmaxinodes: current maximum of available inodes count [out]
* @nfreeinodes: free inodes count [out]
*/
int nilfs_ifile_count_free_inodes(struct inode *ifile,
u64 *nmaxinodes, u64 *nfreeinodes)
{
u64 nused;
int err;
*nmaxinodes = 0;
*nfreeinodes = 0;
nused = atomic64_read(&NILFS_I(ifile)->i_root->inodes_count);
err = nilfs_palloc_count_max_entries(ifile, nused, nmaxinodes);
if (likely(!err))
*nfreeinodes = *nmaxinodes - nused;
return err;
}
/**
* nilfs_ifile_read - read or get ifile inode
* @sb: super block instance
* @root: root object
* @inode_size: size of an inode
* @raw_inode: on-disk ifile inode
* @inodep: buffer to store the inode
*/
int nilfs_ifile_read(struct super_block *sb, struct nilfs_root *root,
size_t inode_size, struct nilfs_inode *raw_inode,
struct inode **inodep)
{
struct inode *ifile;
int err;
ifile = nilfs_iget_locked(sb, root, NILFS_IFILE_INO);
if (unlikely(!ifile))
return -ENOMEM;
if (!(ifile->i_state & I_NEW))
goto out;
err = nilfs_mdt_init(ifile, NILFS_MDT_GFP,
sizeof(struct nilfs_ifile_info));
if (err)
goto failed;
err = nilfs_palloc_init_blockgroup(ifile, inode_size);
if (err)
goto failed;
nilfs_palloc_setup_cache(ifile, &NILFS_IFILE_I(ifile)->palloc_cache);
err = nilfs_read_inode_common(ifile, raw_inode);
if (err)
goto failed;
unlock_new_inode(ifile);
out:
*inodep = ifile;
return 0;
failed:
iget_failed(ifile);
return err;
}