forked from Minki/linux
f11459ad7d
This stops allocating multiple super block instances for a device. All snapshots and a current mode mount (i.e. latest tree) will be controlled with nilfs_root objects that are kept within an sb instance. nilfs_get_sb() is rewritten so that it always has a root object for the latest tree and snapshots make additional root objects. The root dentry of the latest tree is binded to sb->s_root even if it isn't attached on a directory. Root dentries of snapshots or the latest tree are binded to mnt->mnt_root on which they are mounted. With this patch, nilfs_find_sbinfo() function, nilfs->ns_supers list, and nilfs->ns_current back pointer, are deleted. In addition, init_nilfs() and load_nilfs() are simplified since they will be called once for a device, not repeatedly called for mount points. Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
94 lines
2.5 KiB
C
94 lines
2.5 KiB
C
/*
|
|
* sb.h - NILFS on-memory super block structure.
|
|
*
|
|
* 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_SB
|
|
#define _NILFS_SB
|
|
|
|
#include <linux/types.h>
|
|
#include <linux/fs.h>
|
|
|
|
/*
|
|
* Mount options
|
|
*/
|
|
struct nilfs_mount_options {
|
|
unsigned long mount_opt;
|
|
__u64 snapshot_cno;
|
|
};
|
|
|
|
struct the_nilfs;
|
|
struct nilfs_sc_info;
|
|
|
|
/*
|
|
* NILFS super-block data in memory
|
|
*/
|
|
struct nilfs_sb_info {
|
|
/* Mount options */
|
|
unsigned long s_mount_opt;
|
|
uid_t s_resuid;
|
|
gid_t s_resgid;
|
|
|
|
unsigned long s_interval; /* construction interval */
|
|
unsigned long s_watermark; /* threshold of data amount
|
|
for the segment construction */
|
|
|
|
/* Fundamental members */
|
|
struct super_block *s_super; /* reverse pointer to super_block */
|
|
struct the_nilfs *s_nilfs;
|
|
|
|
/* Segment constructor */
|
|
struct list_head s_dirty_files; /* dirty files list */
|
|
struct nilfs_sc_info *s_sc_info; /* segment constructor info */
|
|
spinlock_t s_inode_lock; /* Lock for the nilfs inode.
|
|
It covers s_dirty_files list */
|
|
|
|
/* Inode allocator */
|
|
spinlock_t s_next_gen_lock;
|
|
u32 s_next_generation;
|
|
};
|
|
|
|
static inline struct nilfs_sb_info *NILFS_SB(struct super_block *sb)
|
|
{
|
|
return sb->s_fs_info;
|
|
}
|
|
|
|
static inline struct nilfs_sc_info *NILFS_SC(struct nilfs_sb_info *sbi)
|
|
{
|
|
return sbi->s_sc_info;
|
|
}
|
|
|
|
/*
|
|
* Bit operations for the mount option
|
|
*/
|
|
#define nilfs_clear_opt(sbi, opt) \
|
|
do { (sbi)->s_mount_opt &= ~NILFS_MOUNT_##opt; } while (0)
|
|
#define nilfs_set_opt(sbi, opt) \
|
|
do { (sbi)->s_mount_opt |= NILFS_MOUNT_##opt; } while (0)
|
|
#define nilfs_test_opt(sbi, opt) ((sbi)->s_mount_opt & NILFS_MOUNT_##opt)
|
|
#define nilfs_write_opt(sbi, mask, opt) \
|
|
do { (sbi)->s_mount_opt = \
|
|
(((sbi)->s_mount_opt & ~NILFS_MOUNT_##mask) | \
|
|
NILFS_MOUNT_##opt); \
|
|
} while (0)
|
|
|
|
#endif /* _NILFS_SB */
|