/*
* mdt.h - NILFS meta data file prototype and definitions
*
* Copyright (C) 2005-2008 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 Ryusuke Konishi <ryusuke@osrg.net>
*/
#ifndef _NILFS_MDT_H
#define _NILFS_MDT_H
#include <linux/buffer_head.h>
#include <linux/blockgroup_lock.h>
#include "nilfs.h"
#include "page.h"
/**
* struct nilfs_mdt_info - on-memory private data of meta data files
* @mi_nilfs: back pointer to the_nilfs struct
* @mi_sem: reader/writer semaphore for meta data operations
* @mi_bgl: per-blockgroup locking
* @mi_entry_size: size of an entry
* @mi_first_entry_offset: offset to the first entry
* @mi_entries_per_block: number of entries in a block
* @mi_blocks_per_group: number of blocks in a group
* @mi_blocks_per_desc_block: number of blocks per descriptor block
*/
struct nilfs_mdt_info {
struct the_nilfs *mi_nilfs;
struct rw_semaphore mi_sem;
struct blockgroup_lock *mi_bgl;
unsigned mi_entry_size;
unsigned mi_first_entry_offset;
unsigned long mi_entries_per_block;
unsigned long mi_blocks_per_group;
unsigned long mi_blocks_per_desc_block;
};
static inline struct nilfs_mdt_info *NILFS_MDT(const struct inode *inode)
{
return inode->i_private;
}
static inline struct the_nilfs *NILFS_I_NILFS(struct inode *inode)
{
struct super_block *sb = inode->i_sb;
return sb ? NILFS_SB(sb)->s_nilfs : NILFS_MDT(inode)->mi_nilfs;
}
/* Default GFP flags using highmem */
#define NILFS_MDT_GFP (__GFP_WAIT | __GFP_IO | __GFP_HIGHMEM)
int nilfs_mdt_get_block(struct inode *, unsigned long, int,
void (*init_block)(struct inode *,
struct buffer_head *, void *),
struct buffer_head **);
int nilfs_mdt_delete_block(struct inode *, unsigned long);
int nilfs_mdt_forget_block(struct inode *, unsigned long);
int nilfs_mdt_mark_block_dirty(struct inode *, unsigned long);
int nilfs_mdt_fetch_dirty(struct inode *);
struct inode *nilfs_mdt_new(struct the_nilfs *, struct super_block *, ino_t,
gfp_t);
struct inode *nilfs_mdt_new_common(struct the_nilfs *, struct super_block *,
ino_t, gfp_t);
void nilfs_mdt_destroy(struct inode *);
void nilfs_mdt_clear(struct inode *);
void nilfs_mdt_set_entry_size(struct inode *, unsigned, unsigned);
void nilfs_mdt_set_shadow(struct inode *, struct inode *);
#define nilfs_mdt_mark_buffer_dirty(bh) nilfs_mark_buffer_dirty(bh)
static inline void nilfs_mdt_mark_dirty(struct inode *inode)
{
if (!test_bit(NILFS_I_DIRTY, &NILFS_I(inode)->i_state))
set_bit(NILFS_I_DIRTY, &NILFS_I(inode)->i_state);
}
static inline void nilfs_mdt_clear_dirty(struct inode *inode)
{
clear_bit(NILFS_I_DIRTY, &NILFS_I(inode)->i_state);
}
static inline __u64 nilfs_mdt_cno(struct inode *inode)
{
return NILFS_MDT(inode)->mi_nilfs->ns_cno;
}
#define nilfs_mdt_bgl_lock(inode, bg) \
(&NILFS_MDT(inode)->mi_bgl->locks[(bg) & (NR_BG_LOCKS-1)].lock)
static inline int
nilfs_mdt_read_inode_direct(struct inode *inode, struct buffer_head *bh,
unsigned n)
{
return nilfs_read_inode_common(
inode, (struct nilfs_inode *)(bh->b_data + n));
}
static inline void
nilfs_mdt_write_inode_direct(struct inode *inode, struct buffer_head *bh,
unsigned n)
{
nilfs_write_inode_common(
inode, (struct nilfs_inode *)(bh->b_data + n), 1);
}
#endif /* _NILFS_MDT_H */
