linux/fs/nilfs2/nilfs.h
Jiro SEKIBA b2ac86e1a8 nilfs2: sync super blocks in turns
This will sync super blocks in turns instead of syncing duplicate
super blocks at the time.  This will help searching valid super root
when super block is written into disk before log is written, which is
happen when barrier-less block devices are unmounted uncleanly.  In
the situation, old super block likely points to valid log.

This patch introduces ns_sbwcount member to the nilfs object and adds
nilfs_sb_will_flip() function; ns_sbwcount counts how many times super
blocks write back to the disk.  And, nilfs_sb_will_flip() decides
whether flipping required or not based on the count of ns_sbwcount to
sync super blocks asymmetrically.

The following functions are also changed:

 - nilfs_prepare_super(): flips super blocks according to the
   argument.  The argument is calculated by nilfs_sb_will_flip()
   function.

 - nilfs_cleanup_super(): sets "clean" flag to both super blocks if
   they point to the same checkpoint.

To update both of super block information, caller of
nilfs_commit_super must set the information on both super blocks.

Signed-off-by: Jiro SEKIBA <jir@unicus.jp>
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
2010-07-23 10:02:11 +09:00

325 lines
11 KiB
C

/*
* nilfs.h - NILFS local header file.
*
* 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 Koji Sato <koji@osrg.net>
* Ryusuke Konishi <ryusuke@osrg.net>
*/
#ifndef _NILFS_H
#define _NILFS_H
#include <linux/kernel.h>
#include <linux/buffer_head.h>
#include <linux/spinlock.h>
#include <linux/blkdev.h>
#include <linux/nilfs2_fs.h>
#include "the_nilfs.h"
#include "sb.h"
#include "bmap.h"
#include "bmap_union.h"
/*
* nilfs inode data in memory
*/
struct nilfs_inode_info {
__u32 i_flags;
unsigned long i_state; /* Dynamic state flags */
struct nilfs_bmap *i_bmap;
union nilfs_bmap_union i_bmap_union;
__u64 i_xattr; /* sector_t ??? */
__u32 i_dir_start_lookup;
__u64 i_cno; /* check point number for GC inode */
struct address_space i_btnode_cache;
struct list_head i_dirty; /* List for connecting dirty files */
#ifdef CONFIG_NILFS_XATTR
/*
* Extended attributes can be read independently of the main file
* data. Taking i_sem even when reading would cause contention
* between readers of EAs and writers of regular file data, so
* instead we synchronize on xattr_sem when reading or changing
* EAs.
*/
struct rw_semaphore xattr_sem;
#endif
struct buffer_head *i_bh; /* i_bh contains a new or dirty
disk inode */
struct inode vfs_inode;
};
static inline struct nilfs_inode_info *NILFS_I(const struct inode *inode)
{
return container_of(inode, struct nilfs_inode_info, vfs_inode);
}
static inline struct nilfs_inode_info *
NILFS_BMAP_I(const struct nilfs_bmap *bmap)
{
return container_of((union nilfs_bmap_union *)bmap,
struct nilfs_inode_info,
i_bmap_union);
}
static inline struct inode *NILFS_BTNC_I(struct address_space *btnc)
{
struct nilfs_inode_info *ii =
container_of(btnc, struct nilfs_inode_info, i_btnode_cache);
return &ii->vfs_inode;
}
static inline struct inode *NILFS_AS_I(struct address_space *mapping)
{
return (mapping->host) ? :
container_of(mapping, struct inode, i_data);
}
/*
* Dynamic state flags of NILFS on-memory inode (i_state)
*/
enum {
NILFS_I_NEW = 0, /* Inode is newly created */
NILFS_I_DIRTY, /* The file is dirty */
NILFS_I_QUEUED, /* inode is in dirty_files list */
NILFS_I_BUSY, /* inode is grabbed by a segment
constructor */
NILFS_I_COLLECTED, /* All dirty blocks are collected */
NILFS_I_UPDATED, /* The file has been written back */
NILFS_I_INODE_DIRTY, /* write_inode is requested */
NILFS_I_BMAP, /* has bmap and btnode_cache */
NILFS_I_GCINODE, /* inode for GC, on memory only */
NILFS_I_GCDAT, /* shadow DAT, on memory only */
};
/*
* commit flags for nilfs_commit_super and nilfs_sync_super
*/
enum {
NILFS_SB_COMMIT = 0, /* Commit a super block alternately */
NILFS_SB_COMMIT_ALL /* Commit both super blocks */
};
/*
* Macros to check inode numbers
*/
#define NILFS_MDT_INO_BITS \
((unsigned int)(1 << NILFS_DAT_INO | 1 << NILFS_CPFILE_INO | \
1 << NILFS_SUFILE_INO | 1 << NILFS_IFILE_INO | \
1 << NILFS_ATIME_INO | 1 << NILFS_SKETCH_INO))
#define NILFS_SYS_INO_BITS \
((unsigned int)(1 << NILFS_ROOT_INO) | NILFS_MDT_INO_BITS)
#define NILFS_FIRST_INO(sb) (NILFS_SB(sb)->s_nilfs->ns_first_ino)
#define NILFS_MDT_INODE(sb, ino) \
((ino) < NILFS_FIRST_INO(sb) && (NILFS_MDT_INO_BITS & (1 << (ino))))
#define NILFS_VALID_INODE(sb, ino) \
((ino) >= NILFS_FIRST_INO(sb) || (NILFS_SYS_INO_BITS & (1 << (ino))))
/**
* struct nilfs_transaction_info: context information for synchronization
* @ti_magic: Magic number
* @ti_save: Backup of journal_info field of task_struct
* @ti_flags: Flags
* @ti_count: Nest level
* @ti_garbage: List of inode to be put when releasing semaphore
*/
struct nilfs_transaction_info {
u32 ti_magic;
void *ti_save;
/* This should never used. If this happens,
one of other filesystems has a bug. */
unsigned short ti_flags;
unsigned short ti_count;
struct list_head ti_garbage;
};
/* ti_magic */
#define NILFS_TI_MAGIC 0xd9e392fb
/* ti_flags */
#define NILFS_TI_DYNAMIC_ALLOC 0x0001 /* Allocated from slab */
#define NILFS_TI_SYNC 0x0002 /* Force to construct segment at the
end of transaction. */
#define NILFS_TI_GC 0x0004 /* GC context */
#define NILFS_TI_COMMIT 0x0008 /* Change happened or not */
#define NILFS_TI_WRITER 0x0010 /* Constructor context */
int nilfs_transaction_begin(struct super_block *,
struct nilfs_transaction_info *, int);
int nilfs_transaction_commit(struct super_block *);
void nilfs_transaction_abort(struct super_block *);
static inline void nilfs_set_transaction_flag(unsigned int flag)
{
struct nilfs_transaction_info *ti = current->journal_info;
ti->ti_flags |= flag;
}
static inline int nilfs_test_transaction_flag(unsigned int flag)
{
struct nilfs_transaction_info *ti = current->journal_info;
if (ti == NULL || ti->ti_magic != NILFS_TI_MAGIC)
return 0;
return !!(ti->ti_flags & flag);
}
static inline int nilfs_doing_gc(void)
{
return nilfs_test_transaction_flag(NILFS_TI_GC);
}
static inline int nilfs_doing_construction(void)
{
return nilfs_test_transaction_flag(NILFS_TI_WRITER);
}
static inline struct inode *nilfs_dat_inode(const struct the_nilfs *nilfs)
{
return nilfs_doing_gc() ? nilfs->ns_gc_dat : nilfs->ns_dat;
}
/*
* function prototype
*/
#ifdef CONFIG_NILFS_POSIX_ACL
#error "NILFS: not yet supported POSIX ACL"
extern int nilfs_permission(struct inode *, int, struct nameidata *);
extern int nilfs_acl_chmod(struct inode *);
extern int nilfs_init_acl(struct inode *, struct inode *);
#else
#define nilfs_permission NULL
static inline int nilfs_acl_chmod(struct inode *inode)
{
return 0;
}
static inline int nilfs_init_acl(struct inode *inode, struct inode *dir)
{
inode->i_mode &= ~current_umask();
return 0;
}
#endif
#define NILFS_ATIME_DISABLE
/* dir.c */
extern int nilfs_add_link(struct dentry *, struct inode *);
extern ino_t nilfs_inode_by_name(struct inode *, const struct qstr *);
extern int nilfs_make_empty(struct inode *, struct inode *);
extern struct nilfs_dir_entry *
nilfs_find_entry(struct inode *, const struct qstr *, struct page **);
extern int nilfs_delete_entry(struct nilfs_dir_entry *, struct page *);
extern int nilfs_empty_dir(struct inode *);
extern struct nilfs_dir_entry *nilfs_dotdot(struct inode *, struct page **);
extern void nilfs_set_link(struct inode *, struct nilfs_dir_entry *,
struct page *, struct inode *);
/* file.c */
extern int nilfs_sync_file(struct file *, int);
/* ioctl.c */
long nilfs_ioctl(struct file *, unsigned int, unsigned long);
int nilfs_ioctl_prepare_clean_segments(struct the_nilfs *, struct nilfs_argv *,
void **);
/* inode.c */
extern struct inode *nilfs_new_inode(struct inode *, int);
extern void nilfs_free_inode(struct inode *);
extern int nilfs_get_block(struct inode *, sector_t, struct buffer_head *, int);
extern void nilfs_set_inode_flags(struct inode *);
extern int nilfs_read_inode_common(struct inode *, struct nilfs_inode *);
extern void nilfs_write_inode_common(struct inode *, struct nilfs_inode *, int);
extern struct inode *nilfs_iget(struct super_block *, unsigned long);
extern void nilfs_update_inode(struct inode *, struct buffer_head *);
extern void nilfs_truncate(struct inode *);
extern void nilfs_delete_inode(struct inode *);
extern int nilfs_setattr(struct dentry *, struct iattr *);
extern int nilfs_load_inode_block(struct nilfs_sb_info *, struct inode *,
struct buffer_head **);
extern int nilfs_inode_dirty(struct inode *);
extern int nilfs_set_file_dirty(struct nilfs_sb_info *, struct inode *,
unsigned);
extern int nilfs_mark_inode_dirty(struct inode *);
extern void nilfs_dirty_inode(struct inode *);
/* namei.c */
extern struct dentry *nilfs_get_parent(struct dentry *);
/* super.c */
extern struct inode *nilfs_alloc_inode_common(struct the_nilfs *);
extern struct inode *nilfs_alloc_inode(struct super_block *);
extern void nilfs_destroy_inode(struct inode *);
extern void nilfs_error(struct super_block *, const char *, const char *, ...)
__attribute__ ((format (printf, 3, 4)));
extern void nilfs_warning(struct super_block *, const char *, const char *, ...)
__attribute__ ((format (printf, 3, 4)));
extern struct nilfs_super_block *
nilfs_read_super_block(struct super_block *, u64, int, struct buffer_head **);
extern int nilfs_store_magic_and_option(struct super_block *,
struct nilfs_super_block *, char *);
extern void nilfs_set_log_cursor(struct nilfs_super_block *,
struct the_nilfs *);
extern struct nilfs_super_block **nilfs_prepare_super(struct nilfs_sb_info *,
int flip);
extern int nilfs_commit_super(struct nilfs_sb_info *, int);
extern int nilfs_cleanup_super(struct nilfs_sb_info *);
extern int nilfs_attach_checkpoint(struct nilfs_sb_info *, __u64);
extern void nilfs_detach_checkpoint(struct nilfs_sb_info *);
/* gcinode.c */
int nilfs_gccache_submit_read_data(struct inode *, sector_t, sector_t, __u64,
struct buffer_head **);
int nilfs_gccache_submit_read_node(struct inode *, sector_t, __u64,
struct buffer_head **);
int nilfs_gccache_wait_and_mark_dirty(struct buffer_head *);
int nilfs_init_gccache(struct the_nilfs *);
void nilfs_destroy_gccache(struct the_nilfs *);
void nilfs_clear_gcinode(struct inode *);
struct inode *nilfs_gc_iget(struct the_nilfs *, ino_t, __u64);
void nilfs_remove_all_gcinode(struct the_nilfs *);
/* gcdat.c */
int nilfs_init_gcdat_inode(struct the_nilfs *);
void nilfs_commit_gcdat_inode(struct the_nilfs *);
void nilfs_clear_gcdat_inode(struct the_nilfs *);
/*
* Inodes and files operations
*/
extern const struct file_operations nilfs_dir_operations;
extern const struct inode_operations nilfs_file_inode_operations;
extern const struct file_operations nilfs_file_operations;
extern const struct address_space_operations nilfs_aops;
extern const struct inode_operations nilfs_dir_inode_operations;
extern const struct inode_operations nilfs_special_inode_operations;
extern const struct inode_operations nilfs_symlink_inode_operations;
/*
* filesystem type
*/
extern struct file_system_type nilfs_fs_type;
#endif /* _NILFS_H */