e3154e9748
This directly uses sb->s_fs_info to keep a nilfs filesystem object and
fully removes the intermediate nilfs_sb_info structure. With this
change, the hierarchy of on-memory structures of nilfs will be
simplified as follows:
Before:
super_block
-> nilfs_sb_info
-> the_nilfs
-> cptree --+-> nilfs_root (current file system)
+-> nilfs_root (snapshot A)
+-> nilfs_root (snapshot B)
:
-> nilfs_sc_info (log writer structure)
After:
super_block
-> the_nilfs
-> cptree --+-> nilfs_root (current file system)
+-> nilfs_root (snapshot A)
+-> nilfs_root (snapshot B)
:
-> nilfs_sc_info (log writer structure)
The reason why we didn't design so from the beginning is because the
initial shape also differed from the above. The early hierachy was
composed of "per-mount-point" super_block -> nilfs_sb_info pairs and a
shared nilfs object. On the kernel 2.6.37, it was changed to the
current shape in order to unify super block instances into one per
device, and this cleanup became applicable as the result.
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
118 lines
3.9 KiB
C
118 lines
3.9 KiB
C
/*
|
|
* 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_shadow_map {
|
|
struct nilfs_bmap_store bmap_store;
|
|
struct address_space frozen_data;
|
|
struct address_space frozen_btnodes;
|
|
struct list_head frozen_buffers;
|
|
};
|
|
|
|
/**
|
|
* struct nilfs_mdt_info - on-memory private data of meta data files
|
|
* @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_palloc_cache: persistent object allocator cache
|
|
* @mi_shadow: shadow of bmap and page caches
|
|
* @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 rw_semaphore mi_sem;
|
|
struct blockgroup_lock *mi_bgl;
|
|
unsigned mi_entry_size;
|
|
unsigned mi_first_entry_offset;
|
|
unsigned long mi_entries_per_block;
|
|
struct nilfs_palloc_cache *mi_palloc_cache;
|
|
struct nilfs_shadow_map *mi_shadow;
|
|
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)
|
|
{
|
|
return inode->i_sb->s_fs_info;
|
|
}
|
|
|
|
/* 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 *);
|
|
|
|
int nilfs_mdt_init(struct inode *inode, gfp_t gfp_mask, size_t objsz);
|
|
void nilfs_mdt_set_entry_size(struct inode *, unsigned, unsigned);
|
|
|
|
int nilfs_mdt_setup_shadow_map(struct inode *inode,
|
|
struct nilfs_shadow_map *shadow);
|
|
int nilfs_mdt_save_to_shadow_map(struct inode *inode);
|
|
void nilfs_mdt_restore_from_shadow_map(struct inode *inode);
|
|
void nilfs_mdt_clear_shadow_map(struct inode *inode);
|
|
int nilfs_mdt_freeze_buffer(struct inode *inode, struct buffer_head *bh);
|
|
struct buffer_head *nilfs_mdt_get_frozen_buffer(struct inode *inode,
|
|
struct buffer_head *bh);
|
|
|
|
#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_I_NILFS(inode)->ns_cno;
|
|
}
|
|
|
|
#define nilfs_mdt_bgl_lock(inode, bg) \
|
|
(&NILFS_MDT(inode)->mi_bgl->locks[(bg) & (NR_BG_LOCKS-1)].lock)
|
|
|
|
#endif /* _NILFS_MDT_H */
|