ext3_fs.h

可以在不启动LINUX的情况下直接访问EXT2和EXT3格式的磁盘

	 * the incompatible feature set is that if there is a bit set
	 * in the incompatible feature set that the kernel doesn't
	 * know about, it should refuse to mount the filesystem.
	 *
	 * e2fsck's requirements are more strict; if it doesn't know
	 * about a feature in either the compatible or incompatible
	 * feature set, it must abort and not try to meddle with
	 * things it doesn't understand...
	 */
	__le32	s_first_ino;		/* First non-reserved inode */
	__le16   s_inode_size;		/* size of inode structure */
	__le16	s_block_group_nr;	/* block group # of this superblock */
	__le32	s_feature_compat;	/* compatible feature set */
/*60*/	__le32	s_feature_incompat;	/* incompatible feature set */
	__le32	s_feature_ro_compat;	/* readonly-compatible feature set */
/*68*/	__u8	s_uuid[16];		/* 128-bit uuid for volume */
/*78*/	char	s_volume_name[16];	/* volume name */
/*88*/	char	s_last_mounted[64];	/* directory where last mounted */
/*C8*/	__le32	s_algorithm_usage_bitmap; /* For compression */
	/*
	 * Performance hints.  Directory preallocation should only
	 * happen if the EXT3_FEATURE_COMPAT_DIR_PREALLOC flag is on.
	 */
	__u8	s_prealloc_blocks;	/* Nr of blocks to try to preallocate*/
	__u8	s_prealloc_dir_blocks;	/* Nr to preallocate for dirs */
	__le16	s_reserved_gdt_blocks;	/* Per group desc for online growth */
	/*
	 * Journaling support valid if EXT3_FEATURE_COMPAT_HAS_JOURNAL set.
	 */
/*D0*/	__u8	s_journal_uuid[16];	/* uuid of journal superblock */
/*E0*/	__le32	s_journal_inum;		/* inode number of journal file */
	__le32	s_journal_dev;		/* device number of journal file */
	__le32	s_last_orphan;		/* start of list of inodes to delete */
	__le32	s_hash_seed[4];		/* HTREE hash seed */
	__u8	s_def_hash_version;	/* Default hash version to use */
	__u8	s_reserved_char_pad;
	__u16	s_reserved_word_pad;
	__le32	s_default_mount_opts;
	__le32	s_first_meta_bg;	/* First metablock block group */
	__u32	s_reserved[190];	/* Padding to the end of the block */
};

#if 0
#ifdef __KERNEL__
#include <linux/ext3_fs_i.h>
#include <linux/ext3_fs_sb.h>
static inline struct ext3_sb_info * EXT3_SB(struct super_block *sb)
{
	return sb->s_fs_info;
}
static inline struct ext3_inode_info *EXT3_I(struct inode *inode)
{
	return container_of(inode, struct ext3_inode_info, vfs_inode);
}

static inline int ext3_valid_inum(struct super_block *sb, unsigned long ino)
{
	return ino == EXT3_ROOT_INO ||
		ino == EXT3_JOURNAL_INO ||
		ino == EXT3_RESIZE_INO ||
		(ino >= EXT3_FIRST_INO(sb) &&
		 ino <= le32_to_cpu(EXT3_SB(sb)->s_es->s_inodes_count));
}
#else
/* Assume that user mode programs are passing in an ext3fs superblock, not
 * a kernel struct super_block.  This will allow us to call the feature-test
 * macros from user land. */
#define EXT3_SB(sb)	(sb)
#endif


#define NEXT_ORPHAN(inode) EXT3_I(inode)->i_dtime

/*
 * Codes for operating systems
 */
#define EXT3_OS_LINUX		0
#define EXT3_OS_HURD		1
#define EXT3_OS_MASIX		2
#define EXT3_OS_FREEBSD		3
#define EXT3_OS_LITES		4

/*
 * Revision levels
 */
#define EXT3_GOOD_OLD_REV	0	/* The good old (original) format */
#define EXT3_DYNAMIC_REV	1	/* V2 format w/ dynamic inode sizes */

#define EXT3_CURRENT_REV	EXT3_GOOD_OLD_REV
#define EXT3_MAX_SUPP_REV	EXT3_DYNAMIC_REV

#define EXT3_GOOD_OLD_INODE_SIZE 128

/*
 * Feature set definitions
 */

#define EXT3_HAS_COMPAT_FEATURE(sb,mask)			\
	( EXT3_SB(sb)->s_es->s_feature_compat & cpu_to_le32(mask) )
#define EXT3_HAS_RO_COMPAT_FEATURE(sb,mask)			\
	( EXT3_SB(sb)->s_es->s_feature_ro_compat & cpu_to_le32(mask) )
#define EXT3_HAS_INCOMPAT_FEATURE(sb,mask)			\
	( EXT3_SB(sb)->s_es->s_feature_incompat & cpu_to_le32(mask) )
#define EXT3_SET_COMPAT_FEATURE(sb,mask)			\
	EXT3_SB(sb)->s_es->s_feature_compat |= cpu_to_le32(mask)
#define EXT3_SET_RO_COMPAT_FEATURE(sb,mask)			\
	EXT3_SB(sb)->s_es->s_feature_ro_compat |= cpu_to_le32(mask)
#define EXT3_SET_INCOMPAT_FEATURE(sb,mask)			\
	EXT3_SB(sb)->s_es->s_feature_incompat |= cpu_to_le32(mask)
#define EXT3_CLEAR_COMPAT_FEATURE(sb,mask)			\
	EXT3_SB(sb)->s_es->s_feature_compat &= ~cpu_to_le32(mask)
#define EXT3_CLEAR_RO_COMPAT_FEATURE(sb,mask)			\
	EXT3_SB(sb)->s_es->s_feature_ro_compat &= ~cpu_to_le32(mask)
#define EXT3_CLEAR_INCOMPAT_FEATURE(sb,mask)			\
	EXT3_SB(sb)->s_es->s_feature_incompat &= ~cpu_to_le32(mask)

#define EXT3_FEATURE_COMPAT_DIR_PREALLOC	0x0001
#define EXT3_FEATURE_COMPAT_IMAGIC_INODES	0x0002
#define EXT3_FEATURE_COMPAT_HAS_JOURNAL		0x0004
#define EXT3_FEATURE_COMPAT_EXT_ATTR		0x0008
#define EXT3_FEATURE_COMPAT_RESIZE_INODE	0x0010
#define EXT3_FEATURE_COMPAT_DIR_INDEX		0x0020

#define EXT3_FEATURE_RO_COMPAT_SPARSE_SUPER	0x0001
#define EXT3_FEATURE_RO_COMPAT_LARGE_FILE	0x0002
#define EXT3_FEATURE_RO_COMPAT_BTREE_DIR	0x0004

#define EXT3_FEATURE_INCOMPAT_COMPRESSION	0x0001
#define EXT3_FEATURE_INCOMPAT_FILETYPE		0x0002
#define EXT3_FEATURE_INCOMPAT_RECOVER		0x0004 /* Needs recovery */
#define EXT3_FEATURE_INCOMPAT_JOURNAL_DEV	0x0008 /* Journal device */
#define EXT3_FEATURE_INCOMPAT_META_BG		0x0010

#define EXT3_FEATURE_COMPAT_SUPP	EXT2_FEATURE_COMPAT_EXT_ATTR
#define EXT3_FEATURE_INCOMPAT_SUPP	(EXT3_FEATURE_INCOMPAT_FILETYPE| \
					 EXT3_FEATURE_INCOMPAT_RECOVER| \
					 EXT3_FEATURE_INCOMPAT_META_BG)
#define EXT3_FEATURE_RO_COMPAT_SUPP	(EXT3_FEATURE_RO_COMPAT_SPARSE_SUPER| \
					 EXT3_FEATURE_RO_COMPAT_LARGE_FILE| \
					 EXT3_FEATURE_RO_COMPAT_BTREE_DIR)

/*
 * Default values for user and/or group using reserved blocks
 */
#define	EXT3_DEF_RESUID		0
#define	EXT3_DEF_RESGID		0

/*
 * Default mount options
 */
#define EXT3_DEFM_DEBUG		0x0001
#define EXT3_DEFM_BSDGROUPS	0x0002
#define EXT3_DEFM_XATTR_USER	0x0004
#define EXT3_DEFM_ACL		0x0008
#define EXT3_DEFM_UID16		0x0010
#define EXT3_DEFM_JMODE		0x0060
#define EXT3_DEFM_JMODE_DATA	0x0020
#define EXT3_DEFM_JMODE_ORDERED	0x0040
#define EXT3_DEFM_JMODE_WBACK	0x0060

/*
 * Structure of a directory entry
 */
#define EXT3_NAME_LEN 255

struct ext3_dir_entry {
	__le32	inode;			/* Inode number */
	__le16	rec_len;		/* Directory entry length */
	__le16	name_len;		/* Name length */
	char	name[EXT3_NAME_LEN];	/* File name */
};

/*
 * The new version of the directory entry.  Since EXT3 structures are
 * stored in intel byte order, and the name_len field could never be
 * bigger than 255 chars, it's safe to reclaim the extra byte for the
 * file_type field.
 */
struct ext3_dir_entry_2 {
	__le32	inode;			/* Inode number */
	__le16	rec_len;		/* Directory entry length */
	__u8	name_len;		/* Name length */
	__u8	file_type;
	char	name[EXT3_NAME_LEN];	/* File name */
};

/*
 * Ext3 directory file types.  Only the low 3 bits are used.  The
 * other bits are reserved for now.
 */
#define EXT3_FT_UNKNOWN		0
#define EXT3_FT_REG_FILE	1
#define EXT3_FT_DIR		2
#define EXT3_FT_CHRDEV		3
#define EXT3_FT_BLKDEV		4
#define EXT3_FT_FIFO		5
#define EXT3_FT_SOCK		6
#define EXT3_FT_SYMLINK		7

#define EXT3_FT_MAX		8

/*
 * EXT3_DIR_PAD defines the directory entries boundaries
 *
 * NOTE: It must be a multiple of 4
 */
#define EXT3_DIR_PAD			4
#define EXT3_DIR_ROUND			(EXT3_DIR_PAD - 1)
#define EXT3_DIR_REC_LEN(name_len)	(((name_len) + 8 + EXT3_DIR_ROUND) & \
					 ~EXT3_DIR_ROUND)
#define EXT3_MAX_REC_LEN		((1<<16)-1)

static inline unsigned ext3_rec_len_from_disk(__le16 dlen)
{
	unsigned len = le16_to_cpu(dlen);

	if (len == EXT3_MAX_REC_LEN)
		return 1 << 16;
	return len;
}

static inline __le16 ext3_rec_len_to_disk(unsigned len)
{
	if (len == (1 << 16))
		return cpu_to_le16(EXT3_MAX_REC_LEN);
	else if (len > (1 << 16))
		BUG();
	return cpu_to_le16(len);
}

/*
 * Hash Tree Directory indexing
 * (c) Daniel Phillips, 2001
 */

#define is_dx(dir) (EXT3_HAS_COMPAT_FEATURE(dir->i_sb, \
				      EXT3_FEATURE_COMPAT_DIR_INDEX) && \
		      (EXT3_I(dir)->i_flags & EXT3_INDEX_FL))
#define EXT3_DIR_LINK_MAX(dir) (!is_dx(dir) && (dir)->i_nlink >= EXT3_LINK_MAX)
#define EXT3_DIR_LINK_EMPTY(dir) ((dir)->i_nlink == 2 || (dir)->i_nlink == 1)

/* Legal values for the dx_root hash_version field: */

#define DX_HASH_LEGACY		0
#define DX_HASH_HALF_MD4	1
#define DX_HASH_TEA		2

#ifdef __KERNEL__

/* hash info structure used by the directory hash */
struct dx_hash_info
{
	u32		hash;
	u32		minor_hash;
	int		hash_version;
	u32		*seed;
};

#define EXT3_HTREE_EOF	0x7fffffff

/*
 * Control parameters used by ext3_htree_next_block
 */
#define HASH_NB_ALWAYS		1


/*
 * Describe an inode's exact location on disk and in memory
 */
struct ext3_iloc
{
	struct buffer_head *bh;
	unsigned long offset;
	unsigned long block_group;
};

static inline struct ext3_inode *ext3_raw_inode(struct ext3_iloc *iloc)
{
	return (struct ext3_inode *) (iloc->bh->b_data + iloc->offset);
}

/*
 * This structure is stuffed into the struct file's private_data field
 * for directories.  It is where we put information so that we can do
 * readdir operations in hash tree order.
 */
struct dir_private_info {
	struct rb_root	root;
	struct rb_node	*curr_node;
	struct fname	*extra_fname;
	loff_t		last_pos;
	__u32		curr_hash;
	__u32		curr_minor_hash;
	__u32		next_hash;
};

/* calculate the first block number of the group */
static inline ext3_fsblk_t
ext3_group_first_block_no(struct super_block *sb, unsigned long group_no)
{
	return group_no * (ext3_fsblk_t)EXT3_BLOCKS_PER_GROUP(sb) +
		le32_to_cpu(EXT3_SB(sb)->s_es->s_first_data_block);
}

/*
 * Special error return code only used by dx_probe() and its callers.
 */
#define ERR_BAD_DX_DIR	-75000

/*
 * Function prototypes
 */

/*
 * Ok, these declarations are also in <linux/kernel.h> but none of the
 * ext3 source programs needs to include it so they are duplicated here.
 */
# define NORET_TYPE    /**/
# define ATTRIB_NORET  __attribute__((noreturn))
# define NORET_AND     noreturn,

/* balloc.c */
extern int ext3_bg_has_super(struct super_block *sb, int group);
extern unsigned long ext3_bg_num_gdb(struct super_block *sb, int group);
extern ext3_fsblk_t ext3_new_block (handle_t *handle, struct inode *inode,
			ext3_fsblk_t goal, int *errp);
extern ext3_fsblk_t ext3_new_blocks (handle_t *handle, struct inode *inode,
			ext3_fsblk_t goal, unsigned long *count, int *errp);
extern void ext3_free_blocks (handle_t *handle, struct inode *inode,
			ext3_fsblk_t block, unsigned long count);
extern void ext3_free_blocks_sb (handle_t *handle, struct super_block *sb,
				 ext3_fsblk_t block, unsigned long count,
				unsigned long *pdquot_freed_blocks);
extern ext3_fsblk_t ext3_count_free_blocks (struct super_block *);
extern void ext3_check_blocks_bitmap (struct super_block *);
extern struct ext3_group_desc * ext3_get_group_desc(struct super_block * sb,
						    unsigned int block_group,
						    struct buffer_head ** bh);
extern int ext3_should_retry_alloc(struct super_block *sb, int *retries);
extern void ext3_init_block_alloc_info(struct inode *);
extern void ext3_rsv_window_add(struct super_block *sb, struct ext3_reserve_window_node *rsv);

/* dir.c */
extern int ext3_check_dir_entry(const char *, struct inode *,
				struct ext3_dir_entry_2 *,
				struct buffer_head *, unsigned long);
extern int ext3_htree_store_dirent(struct file *dir_file, __u32 hash,
				    __u32 minor_hash,
				    struct ext3_dir_entry_2 *dirent);
extern void ext3_htree_free_dir_info(struct dir_private_info *p);

/* fsync.c */
extern int ext3_sync_file (struct file *, struct dentry *, int);

/* hash.c */
extern int ext3fs_dirhash(const char *name, int len, struct
			  dx_hash_info *hinfo);

/* ialloc.c */
extern struct inode * ext3_new_inode (handle_t *, struct inode *, int);
extern void ext3_free_inode (handle_t *, struct inode *);
extern struct inode * ext3_orphan_get (struct super_block *, unsigned long);
extern unsigned long ext3_count_free_inodes (struct super_block *);
extern unsigned long ext3_count_dirs (struct super_block *);
extern void ext3_check_inodes_bitmap (struct super_block *);
extern unsigned long ext3_count_free (struct buffer_head *, unsigned);


/* inode.c */
int ext3_forget(handle_t *handle, int is_metadata, struct inode *inode,
		struct buffer_head *bh, ext3_fsblk_t blocknr);
struct buffer_head * ext3_getblk (handle_t *, struct inode *, long, int, int *);
struct buffer_head * ext3_bread (handle_t *, struct inode *, int, int, int *);
int ext3_get_blocks_handle(handle_t *handle, struct inode *inode,
	sector_t iblock, unsigned long maxblocks, struct buffer_head *bh_result,
	int create, int extend_disksize);

extern struct inode *ext3_iget(struct super_block *, unsigned long);
extern int  ext3_write_inode (struct inode *, int);
extern int  ext3_setattr (struct dentry *, struct iattr *);
extern void ext3_delete_inode (struct inode *);
extern int  ext3_sync_inode (handle_t *, struct inode *);
extern void ext3_discard_reservation (struct inode *);
extern void ext3_dirty_inode(struct inode *);
extern int ext3_change_inode_journal_flag(struct inode *, int);
extern int ext3_get_inode_loc(struct inode *, struct ext3_iloc *);
extern void ext3_truncate (struct inode *);
extern void ext3_set_inode_flags(struct inode *);
extern void ext3_get_inode_flags(struct ext3_inode_info *);
extern void ext3_set_aops(struct inode *inode);

/* ioctl.c */
extern int ext3_ioctl (struct inode *, struct file *, unsigned int,
		       unsigned long);
extern long ext3_compat_ioctl (struct file *, unsigned int, unsigned long);

/* namei.c */
extern int ext3_orphan_add(handle_t *, struct inode *);
extern int ext3_orphan_del(handle_t *, struct inode *);
extern int ext3_htree_fill_tree(struct file *dir_file, __u32 start_hash,
				__u32 start_minor_hash, __u32 *next_hash);

/* resize.c */
extern int ext3_group_add(struct super_block *sb,
				struct ext3_new_group_data *input);
extern int ext3_group_extend(struct super_block *sb,
				struct ext3_super_block *es,
				ext3_fsblk_t n_blocks_count);

/* super.c */
extern void ext3_error (struct super_block *, const char *, const char *, ...)
	__attribute__ ((format (printf, 3, 4)));
extern void __ext3_std_error (struct super_block *, const char *, int);
extern void ext3_abort (struct super_block *, const char *, const char *, ...)
	__attribute__ ((format (printf, 3, 4)));
extern void ext3_warning (struct super_block *, const char *, const char *, ...)
	__attribute__ ((format (printf, 3, 4)));
extern void ext3_update_dynamic_rev (struct super_block *sb);

#define ext3_std_error(sb, errno)				\
do {								\
	if ((errno))						\
		__ext3_std_error((sb), __FUNCTION__, (errno));	\
} while (0)

/*
 * Inodes and files operations
 */

/* dir.c */
extern const struct file_operations ext3_dir_operations;

/* file.c */
extern const struct inode_operations ext3_file_inode_operations;
extern const struct file_operations ext3_file_operations;

/* namei.c */
extern const struct inode_operations ext3_dir_inode_operations;
extern const struct inode_operations ext3_special_inode_operations;

/* symlink.c */
extern const struct inode_operations ext3_symlink_inode_operations;
extern const struct inode_operations ext3_fast_symlink_inode_operations;


#endif	/* __KERNEL__ */

#endif /* 0 */
#endif	/* _LINUX_EXT3_FS_H */