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

/*
 *  linux/include/linux/ext3_fs.h
 *
 * Copyright (C) 1992, 1993, 1994, 1995
 * Remy Card ([e-mail])
 * Laboratoire MASI - Institut Blaise Pascal
 * Universite Pierre et Marie Curie (Paris VI)
 *
 *  from
 *
 *  linux/include/linux/minix_fs.h
 *
 *  Copyright (C) 1991, 1992  Linus Torvalds
 */

#ifndef _LINUX_EXT3_FS_H
#define _LINUX_EXT3_FS_H

#include <linux/types.h>
#include <linux/magic.h>

/*
 * The second extended filesystem constants/structures
 */

/*
 * Define EXT3FS_DEBUG to produce debug messages
 */
#undef EXT3FS_DEBUG

/*
 * Define EXT3_RESERVATION to reserve data blocks for expanding files
 */
#define EXT3_DEFAULT_RESERVE_BLOCKS     8
/*max window size: 1024(direct blocks) + 3([t,d]indirect blocks) */
#define EXT3_MAX_RESERVE_BLOCKS         1027
#define EXT3_RESERVE_WINDOW_NOT_ALLOCATED 0

/*
 * Debug code
 */
#ifdef EXT3FS_DEBUG
#define ext3_debug(f, a...)						\
	do {								\
		printk (KERN_DEBUG "EXT3-fs DEBUG (%s, %d): %s:",	\
			__FILE__, __LINE__, __FUNCTION__);		\
		printk (KERN_DEBUG f, ## a);				\
	} while (0)
#else
#define ext3_debug
#endif

/*
 * Special inodes numbers
 */
#define	EXT3_BAD_INO		 1	/* Bad blocks inode */
#define EXT3_ROOT_INO		 2	/* Root inode */
#define EXT3_BOOT_LOADER_INO	 5	/* Boot loader inode */
#define EXT3_UNDEL_DIR_INO	 6	/* Undelete directory inode */
#define EXT3_RESIZE_INO		 7	/* Reserved group descriptors inode */
#define EXT3_JOURNAL_INO	 8	/* Journal inode */

/* First non-reserved inode for old ext3 filesystems */
#define EXT3_GOOD_OLD_FIRST_INO	11

/*
 * Maximal count of links to a file
 */
#define EXT3_LINK_MAX		32000

/*
 * Macro-instructions used to manage several block sizes
 */
#define EXT3_MIN_BLOCK_SIZE		1024
#define	EXT3_MAX_BLOCK_SIZE		65536
#define EXT3_MIN_BLOCK_LOG_SIZE		10
#ifdef __KERNEL__
# define EXT3_BLOCK_SIZE(s)		((s)->s_blocksize)
#else
# define EXT3_BLOCK_SIZE(s)		(EXT3_MIN_BLOCK_SIZE << (s)->s_log_block_size)
#endif
#define	EXT3_ADDR_PER_BLOCK(s)		(EXT3_BLOCK_SIZE(s) / sizeof (__u32))
#ifdef __KERNEL__
# define EXT3_BLOCK_SIZE_BITS(s)	((s)->s_blocksize_bits)
#else
# define EXT3_BLOCK_SIZE_BITS(s)	((s)->s_log_block_size + 10)
#endif
#ifdef __KERNEL__
#define	EXT3_ADDR_PER_BLOCK_BITS(s)	(EXT3_SB(s)->s_addr_per_block_bits)
#define EXT3_INODE_SIZE(s)		(EXT3_SB(s)->s_inode_size)
#define EXT3_FIRST_INO(s)		(EXT3_SB(s)->s_first_ino)
#else
#define EXT3_INODE_SIZE(s)	(((s)->s_rev_level == EXT3_GOOD_OLD_REV) ? \
				 EXT3_GOOD_OLD_INODE_SIZE : \
				 (s)->s_inode_size)
#define EXT3_FIRST_INO(s)	(((s)->s_rev_level == EXT3_GOOD_OLD_REV) ? \
				 EXT3_GOOD_OLD_FIRST_INO : \
				 (s)->s_first_ino)
#endif

/*
 * Macro-instructions used to manage fragments
 */
#define EXT3_MIN_FRAG_SIZE		1024
#define	EXT3_MAX_FRAG_SIZE		4096
#define EXT3_MIN_FRAG_LOG_SIZE		  10
#ifdef __KERNEL__
# define EXT3_FRAG_SIZE(s)		(EXT3_SB(s)->s_frag_size)
# define EXT3_FRAGS_PER_BLOCK(s)	(EXT3_SB(s)->s_frags_per_block)
#else
# define EXT3_FRAG_SIZE(s)		(EXT3_MIN_FRAG_SIZE << (s)->s_log_frag_size)
# define EXT3_FRAGS_PER_BLOCK(s)	(EXT3_BLOCK_SIZE(s) / EXT3_FRAG_SIZE(s))
#endif

/*
 * Structure of a blocks group descriptor
 */
struct ext3_group_desc
{
	__le32	bg_block_bitmap;		/* Blocks bitmap block */
	__le32	bg_inode_bitmap;		/* Inodes bitmap block */
	__le32	bg_inode_table;		/* Inodes table block */
	__le16	bg_free_blocks_count;	/* Free blocks count */
	__le16	bg_free_inodes_count;	/* Free inodes count */
	__le16	bg_used_dirs_count;	/* Directories count */
	__u16	bg_pad;
	__le32	bg_reserved[3];
};

/*
 * Macro-instructions used to manage group descriptors
 */
#ifdef __KERNEL__
# define EXT3_BLOCKS_PER_GROUP(s)	(EXT3_SB(s)->s_blocks_per_group)
# define EXT3_DESC_PER_BLOCK(s)		(EXT3_SB(s)->s_desc_per_block)
# define EXT3_INODES_PER_GROUP(s)	(EXT3_SB(s)->s_inodes_per_group)
# define EXT3_DESC_PER_BLOCK_BITS(s)	(EXT3_SB(s)->s_desc_per_block_bits)
#else
# define EXT3_BLOCKS_PER_GROUP(s)	((s)->s_blocks_per_group)
# define EXT3_DESC_PER_BLOCK(s)		(EXT3_BLOCK_SIZE(s) / sizeof (struct ext3_group_desc))
# define EXT3_INODES_PER_GROUP(s)	((s)->s_inodes_per_group)
#endif

/*
 * Constants relative to the data blocks
 */
#define	EXT3_NDIR_BLOCKS		12
#define	EXT3_IND_BLOCK			EXT3_NDIR_BLOCKS
#define	EXT3_DIND_BLOCK			(EXT3_IND_BLOCK + 1)
#define	EXT3_TIND_BLOCK			(EXT3_DIND_BLOCK + 1)
#define	EXT3_N_BLOCKS			(EXT3_TIND_BLOCK + 1)

/*
 * Inode flags
 */
#define	EXT3_SECRM_FL			0x00000001 /* Secure deletion */
#define	EXT3_UNRM_FL			0x00000002 /* Undelete */
#define	EXT3_COMPR_FL			0x00000004 /* Compress file */
#define EXT3_SYNC_FL			0x00000008 /* Synchronous updates */
#define EXT3_IMMUTABLE_FL		0x00000010 /* Immutable file */
#define EXT3_APPEND_FL			0x00000020 /* writes to file may only append */
#define EXT3_NODUMP_FL			0x00000040 /* do not dump file */
#define EXT3_NOATIME_FL			0x00000080 /* do not update atime */
/* Reserved for compression usage... */
#define EXT3_DIRTY_FL			0x00000100
#define EXT3_COMPRBLK_FL		0x00000200 /* One or more compressed clusters */
#define EXT3_NOCOMPR_FL			0x00000400 /* Don't compress */
#define EXT3_ECOMPR_FL			0x00000800 /* Compression error */
/* End compression flags --- maybe not all used */
#define EXT3_INDEX_FL			0x00001000 /* hash-indexed directory */
#define EXT3_IMAGIC_FL			0x00002000 /* AFS directory */
#define EXT3_JOURNAL_DATA_FL		0x00004000 /* file data should be journaled */
#define EXT3_NOTAIL_FL			0x00008000 /* file tail should not be merged */
#define EXT3_DIRSYNC_FL			0x00010000 /* dirsync behaviour (directories only) */
#define EXT3_TOPDIR_FL			0x00020000 /* Top of directory hierarchies*/
#define EXT3_RESERVED_FL		0x80000000 /* reserved for ext3 lib */

#define EXT3_FL_USER_VISIBLE		0x0003DFFF /* User visible flags */
#define EXT3_FL_USER_MODIFIABLE		0x000380FF /* User modifiable flags */

/*
 * Inode dynamic state flags
 */
#define EXT3_STATE_JDATA		0x00000001 /* journaled data exists */
#define EXT3_STATE_NEW			0x00000002 /* inode is newly created */
#define EXT3_STATE_XATTR		0x00000004 /* has in-inode xattrs */

/* Used to pass group descriptor data when online resize is done */
struct ext3_new_group_input {
	__u32 group;            /* Group number for this data */
	__u32 block_bitmap;     /* Absolute block number of block bitmap */
	__u32 inode_bitmap;     /* Absolute block number of inode bitmap */
	__u32 inode_table;      /* Absolute block number of inode table start */
	__u32 blocks_count;     /* Total number of blocks in this group */
	__u16 reserved_blocks;  /* Number of reserved blocks in this group */
	__u16 unused;
};

/* The struct ext3_new_group_input in kernel space, with free_blocks_count */
struct ext3_new_group_data {
	__u32 group;
	__u32 block_bitmap;
	__u32 inode_bitmap;
	__u32 inode_table;
	__u32 blocks_count;
	__u16 reserved_blocks;
	__u16 unused;
	__u32 free_blocks_count;
};


/*
 * ioctl commands
 */
#define	EXT3_IOC_GETFLAGS		FS_IOC_GETFLAGS
#define	EXT3_IOC_SETFLAGS		FS_IOC_SETFLAGS
#define	EXT3_IOC_GETVERSION		_IOR('f', 3, long)
#define	EXT3_IOC_SETVERSION		_IOW('f', 4, long)
#define EXT3_IOC_GROUP_EXTEND		_IOW('f', 7, unsigned long)
#define EXT3_IOC_GROUP_ADD		_IOW('f', 8,struct ext3_new_group_input)
#define	EXT3_IOC_GETVERSION_OLD		FS_IOC_GETVERSION
#define	EXT3_IOC_SETVERSION_OLD		FS_IOC_SETVERSION
#ifdef CONFIG_JBD_DEBUG
#define EXT3_IOC_WAIT_FOR_READONLY	_IOR('f', 99, long)
#endif
#define EXT3_IOC_GETRSVSZ		_IOR('f', 5, long)
#define EXT3_IOC_SETRSVSZ		_IOW('f', 6, long)

/*
 * ioctl commands in 32 bit emulation
 */
#define EXT3_IOC32_GETFLAGS		FS_IOC32_GETFLAGS
#define EXT3_IOC32_SETFLAGS		FS_IOC32_SETFLAGS
#define EXT3_IOC32_GETVERSION		_IOR('f', 3, int)
#define EXT3_IOC32_SETVERSION		_IOW('f', 4, int)
#define EXT3_IOC32_GETRSVSZ		_IOR('f', 5, int)
#define EXT3_IOC32_SETRSVSZ		_IOW('f', 6, int)
#define EXT3_IOC32_GROUP_EXTEND		_IOW('f', 7, unsigned int)
#ifdef CONFIG_JBD_DEBUG
#define EXT3_IOC32_WAIT_FOR_READONLY	_IOR('f', 99, int)
#endif
#define EXT3_IOC32_GETVERSION_OLD	FS_IOC32_GETVERSION
#define EXT3_IOC32_SETVERSION_OLD	FS_IOC32_SETVERSION


/*
 *  Mount options
 */
struct ext3_mount_options {
	unsigned long s_mount_opt;
	uid_t s_resuid;
	gid_t s_resgid;
	unsigned long s_commit_interval;
#ifdef CONFIG_QUOTA
	int s_jquota_fmt;
	char *s_qf_names[MAXQUOTAS];
#endif
};

/*
 * Structure of an inode on the disk
 */
struct ext3_inode {
	__le16	i_mode;		/* File mode */
	__le16	i_uid;		/* Low 16 bits of Owner Uid */
	__le32	i_size;		/* Size in bytes */
	__le32	i_atime;	/* Access time */
	__le32	i_ctime;	/* Creation time */
	__le32	i_mtime;	/* Modification time */
	__le32	i_dtime;	/* Deletion Time */
	__le16	i_gid;		/* Low 16 bits of Group Id */
	__le16	i_links_count;	/* Links count */
	__le32	i_blocks;	/* Blocks count */
	__le32	i_flags;	/* File flags */
	union {
		struct {
			__u32  l_i_reserved1;
		} linux1;
		struct {
			__u32  h_i_translator;
		} hurd1;
		struct {
			__u32  m_i_reserved1;
		} masix1;
	} osd1;				/* OS dependent 1 */
	__le32	i_block[EXT3_N_BLOCKS];/* Pointers to blocks */
	__le32	i_generation;	/* File version (for NFS) */
	__le32	i_file_acl;	/* File ACL */
	__le32	i_dir_acl;	/* Directory ACL */
	__le32	i_faddr;	/* Fragment address */
	union {
		struct {
			__u8	l_i_frag;	/* Fragment number */
			__u8	l_i_fsize;	/* Fragment size */
			__u16	i_pad1;
			__le16	l_i_uid_high;	/* these 2 fields    */
			__le16	l_i_gid_high;	/* were reserved2[0] */
			__u32	l_i_reserved2;
		} linux2;
		struct {
			__u8	h_i_frag;	/* Fragment number */
			__u8	h_i_fsize;	/* Fragment size */
			__u16	h_i_mode_high;
			__u16	h_i_uid_high;
			__u16	h_i_gid_high;
			__u32	h_i_author;
		} hurd2;
		struct {
			__u8	m_i_frag;	/* Fragment number */
			__u8	m_i_fsize;	/* Fragment size */
			__u16	m_pad1;
			__u32	m_i_reserved2[2];
		} masix2;
	} osd2;				/* OS dependent 2 */
	__le16	i_extra_isize;
	__le16	i_pad1;
};

#define i_size_high	i_dir_acl

#if defined(__KERNEL__) || defined(__linux__)
#define i_reserved1	osd1.linux1.l_i_reserved1
#define i_frag		osd2.linux2.l_i_frag
#define i_fsize		osd2.linux2.l_i_fsize
#define i_uid_low	i_uid
#define i_gid_low	i_gid
#define i_uid_high	osd2.linux2.l_i_uid_high
#define i_gid_high	osd2.linux2.l_i_gid_high
#define i_reserved2	osd2.linux2.l_i_reserved2

#elif defined(__GNU__)

#define i_translator	osd1.hurd1.h_i_translator
#define i_frag		osd2.hurd2.h_i_frag;
#define i_fsize		osd2.hurd2.h_i_fsize;
#define i_uid_high	osd2.hurd2.h_i_uid_high
#define i_gid_high	osd2.hurd2.h_i_gid_high
#define i_author	osd2.hurd2.h_i_author

#elif defined(__masix__)

#define i_reserved1	osd1.masix1.m_i_reserved1
#define i_frag		osd2.masix2.m_i_frag
#define i_fsize		osd2.masix2.m_i_fsize
#define i_reserved2	osd2.masix2.m_i_reserved2

#endif /* defined(__KERNEL__) || defined(__linux__) */

/*
 * File system states
 */
#define	EXT3_VALID_FS			0x0001	/* Unmounted cleanly */
#define	EXT3_ERROR_FS			0x0002	/* Errors detected */
#define	EXT3_ORPHAN_FS			0x0004	/* Orphans being recovered */

/*
 * Mount flags
 */
#define EXT3_MOUNT_CHECK		0x00001	/* Do mount-time checks */
#define EXT3_MOUNT_OLDALLOC		0x00002  /* Don't use the new Orlov allocator */
#define EXT3_MOUNT_GRPID		0x00004	/* Create files with directory's group */
#define EXT3_MOUNT_DEBUG		0x00008	/* Some debugging messages */
#define EXT3_MOUNT_ERRORS_CONT		0x00010	/* Continue on errors */
#define EXT3_MOUNT_ERRORS_RO		0x00020	/* Remount fs ro on errors */
#define EXT3_MOUNT_ERRORS_PANIC		0x00040	/* Panic on errors */
#define EXT3_MOUNT_MINIX_DF		0x00080	/* Mimics the Minix statfs */
#define EXT3_MOUNT_NOLOAD		0x00100	/* Don't use existing journal*/
#define EXT3_MOUNT_ABORT		0x00200	/* Fatal error detected */
#define EXT3_MOUNT_DATA_FLAGS		0x00C00	/* Mode for data writes: */
#define EXT3_MOUNT_JOURNAL_DATA		0x00400	/* Write data to journal */
#define EXT3_MOUNT_ORDERED_DATA		0x00800	/* Flush data before commit */
#define EXT3_MOUNT_WRITEBACK_DATA	0x00C00	/* No data ordering */
#define EXT3_MOUNT_UPDATE_JOURNAL	0x01000	/* Update the journal format */
#define EXT3_MOUNT_NO_UID32		0x02000  /* Disable 32-bit UIDs */
#define EXT3_MOUNT_XATTR_USER		0x04000	/* Extended user attributes */
#define EXT3_MOUNT_POSIX_ACL		0x08000	/* POSIX Access Control Lists */
#define EXT3_MOUNT_RESERVATION		0x10000	/* Preallocation */
#define EXT3_MOUNT_BARRIER		0x20000 /* Use block barriers */
#define EXT3_MOUNT_NOBH			0x40000 /* No bufferheads */
#define EXT3_MOUNT_QUOTA		0x80000 /* Some quota option set */
#define EXT3_MOUNT_USRQUOTA		0x100000 /* "old" user quota */
#define EXT3_MOUNT_GRPQUOTA		0x200000 /* "old" group quota */

/* Compatibility, for having both ext2_fs.h and ext3_fs.h included at once */
#ifndef _LINUX_EXT2_FS_H
#define clear_opt(o, opt)		o &= ~EXT3_MOUNT_##opt
#define set_opt(o, opt)			o |= EXT3_MOUNT_##opt
#define test_opt(sb, opt)		(EXT3_SB(sb)->s_mount_opt & \
					 EXT3_MOUNT_##opt)
#else
#define EXT2_MOUNT_NOLOAD		EXT3_MOUNT_NOLOAD
#define EXT2_MOUNT_ABORT		EXT3_MOUNT_ABORT
#define EXT2_MOUNT_DATA_FLAGS		EXT3_MOUNT_DATA_FLAGS
#endif

#define ext3_set_bit			ext2_set_bit
#define ext3_set_bit_atomic		ext2_set_bit_atomic
#define ext3_clear_bit			ext2_clear_bit
#define ext3_clear_bit_atomic		ext2_clear_bit_atomic
#define ext3_test_bit			ext2_test_bit
#define ext3_find_first_zero_bit	ext2_find_first_zero_bit
#define ext3_find_next_zero_bit		ext2_find_next_zero_bit

/*
 * Maximal mount counts between two filesystem checks
 */
#define EXT3_DFL_MAX_MNT_COUNT		20	/* Allow 20 mounts */
#define EXT3_DFL_CHECKINTERVAL		0	/* Don't use interval check */

/*
 * Behaviour when detecting errors
 */
#define EXT3_ERRORS_CONTINUE		1	/* Continue execution */
#define EXT3_ERRORS_RO			2	/* Remount fs read-only */
#define EXT3_ERRORS_PANIC		3	/* Panic */
#define EXT3_ERRORS_DEFAULT		EXT3_ERRORS_CONTINUE

/*
 * Structure of the super block
 */
struct ext3_super_block {
/*00*/	__le32	s_inodes_count;		/* Inodes count */
	__le32	s_blocks_count;		/* Blocks count */
	__le32	s_r_blocks_count;	/* Reserved blocks count */
	__le32	s_free_blocks_count;	/* Free blocks count */
/*10*/	__le32	s_free_inodes_count;	/* Free inodes count */
	__le32	s_first_data_block;	/* First Data Block */
	__le32	s_log_block_size;	/* Block size */
	__le32	s_log_frag_size;	/* Fragment size */
/*20*/	__le32	s_blocks_per_group;	/* # Blocks per group */
	__le32	s_frags_per_group;	/* # Fragments per group */
	__le32	s_inodes_per_group;	/* # Inodes per group */
	__le32	s_mtime;		/* Mount time */
/*30*/	__le32	s_wtime;		/* Write time */
	__le16	s_mnt_count;		/* Mount count */
	__le16	s_max_mnt_count;	/* Maximal mount count */
	__le16	s_magic;		/* Magic signature */
	__le16	s_state;		/* File system state */
	__le16	s_errors;		/* Behaviour when detecting errors */
	__le16	s_minor_rev_level;	/* minor revision level */
/*40*/	__le32	s_lastcheck;		/* time of last check */
	__le32	s_checkinterval;	/* max. time between checks */
	__le32	s_creator_os;		/* OS */
	__le32	s_rev_level;		/* Revision level */
/*50*/	__le16	s_def_resuid;		/* Default uid for reserved blocks */
	__le16	s_def_resgid;		/* Default gid for reserved blocks */
	/*
	 * These fields are for EXT3_DYNAMIC_REV superblocks only.
	 *
	 * Note: the difference between the compatible feature set and