path: root/ext2fs/ext2_fs.h

/*
 *  linux/include/linux/ext2_fs.h
 *
 * Copyright (C) 1992, 1993, 1994, 1995
 * Remy Card (card@masi.ibp.fr)
 * 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_EXT2_FS_H
#define _LINUX_EXT2_FS_H

typedef unsigned long u32;
typedef long s32;
typedef unsigned short u16;
typedef short s16;
typedef unsigned char u8;
typedef signed char s8;

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

/*
 * Define EXT2FS_DEBUG to produce debug messages
 */
#undef EXT2FS_DEBUG

/*
 * Define EXT2FS_DEBUG_CACHE to produce cache debug messages
 */
#undef EXT2FS_DEBUG_CACHE

/*
 * Define EXT2FS_CHECK_CACHE to add some checks to the name cache code
 */
#undef EXT2FS_CHECK_CACHE

/*
 * Define EXT2FS_PRE_02B_COMPAT to convert ext 2 fs prior to 0.2b
 */
#undef EXT2FS_PRE_02B_COMPAT

/*
 * Define EXT2_PREALLOCATE to preallocate data blocks for expanding files
 */
#define EXT2_PREALLOCATE

/*
 * The second extended file system version
 */
#define EXT2FS_DATE		"95/03/19"
#define EXT2FS_VERSION		"0.5a"

/*
 * Debug code
 */
#ifdef EXT2FS_DEBUG
extern int ext2_debug_flag;
#define ext2_debug(f, a...) \
 do { if (ext2_debug_flag) printf ("ext2fs: (debug) %s: " f "\n", __FUNCTION__ , ## a); } while (0)
#else
#define ext2_debug(f, a...)	(void)0
#endif

/*
 * Special inodes numbers
 */
#define	EXT2_BAD_INO		 1	/* Bad blocks inode */
#define EXT2_ROOT_INO		 2	/* Root inode */
#define EXT2_ACL_IDX_INO	 3	/* ACL inode */
#define EXT2_ACL_DATA_INO	 4	/* ACL inode */
#define EXT2_BOOT_LOADER_INO	 5	/* Boot loader inode */
#define EXT2_UNDEL_DIR_INO	 6	/* Undelete directory inode */
#define EXT2_FIRST_INO		11	/* First non reserved inode */

/*
 * The second extended file system magic number
 */
#define EXT2_PRE_02B_MAGIC	0xEF51
#define EXT2_SUPER_MAGIC	0xEF53

/*
 * Maximal count of links to a file
 */
#define EXT2_LINK_MAX		32000

/*
 * Macro-instructions used to manage several block sizes
 */
#define EXT2_MIN_BLOCK_SIZE		1024
#define	EXT2_MAX_BLOCK_SIZE		4096
#define EXT2_MIN_BLOCK_LOG_SIZE		  10
#ifdef __KERNEL__
# define EXT2_BLOCK_SIZE(s)		((s)->s_blocksize)
#else
# define EXT2_BLOCK_SIZE(s)		(EXT2_MIN_BLOCK_SIZE << (s)->s_log_block_size)
#endif
#define EXT2_ACLE_PER_BLOCK(s)		(EXT2_BLOCK_SIZE(s) / sizeof (struct ext2_acl_entry))
#define	EXT2_ADDR_PER_BLOCK(s)		(EXT2_BLOCK_SIZE(s) / sizeof (u32))
#ifdef __KERNEL__
# define EXT2_BLOCK_SIZE_BITS(s)	((s)->u.ext2_sb.s_es->s_log_block_size + 10)
#else
# define EXT2_BLOCK_SIZE_BITS(s)	((s)->s_log_block_size + 10)
#endif
#define	EXT2_INODES_PER_BLOCK(s)	(EXT2_BLOCK_SIZE(s) / sizeof (struct ext2_inode))

/*
 * Macro-instructions used to manage fragments
 */
#define EXT2_MIN_FRAG_SIZE		1024
#define	EXT2_MAX_FRAG_SIZE		4096
#define EXT2_MIN_FRAG_LOG_SIZE		  10
#ifdef __KERNEL__
# define EXT2_FRAG_SIZE(s)		((s)->u.ext2_sb.s_frag_size)
# define EXT2_FRAGS_PER_BLOCK(s)	((s)->u.ext2_sb.s_frags_per_block)
#else
# define EXT2_FRAG_SIZE(s)		(EXT2_MIN_FRAG_SIZE << (s)->s_log_frag_size)
# define EXT2_FRAGS_PER_BLOCK(s)	(EXT2_BLOCK_SIZE(s) / EXT2_FRAG_SIZE(s))
#endif

/*
 * ACL structures
 */
struct ext2_acl_header	/* Header of Access Control Lists */
{
	u32	aclh_size;
	u32	aclh_file_count;
	u32	aclh_acle_count;
	u32	aclh_first_acle;
};

struct ext2_acl_entry	/* Access Control List Entry */
{
	u32	acle_size;
	u16	acle_perms;	/* Access permissions */
	u16	acle_type;	/* Type of entry */
	u16	acle_tag;	/* User or group identity */
	u16	acle_pad1;
	u32	acle_next;	/* Pointer on next entry for the */
					/* same inode or on next free entry */
};

/*
 * Structure of a blocks group descriptor
 */
struct ext2_old_group_desc
{
	u32	bg_block_bitmap;		/* Blocks bitmap block */
	u32	bg_inode_bitmap;		/* Inodes bitmap block */
	u32	bg_inode_table;		/* Inodes table block */
	u16	bg_free_blocks_count;	/* Free blocks count */
	u16	bg_free_inodes_count;	/* Free inodes count */
};

struct ext2_group_desc
{
	u32	bg_block_bitmap;		/* Blocks bitmap block */
	u32	bg_inode_bitmap;		/* Inodes bitmap block */
	u32	bg_inode_table;		/* Inodes table block */
	u16	bg_free_blocks_count;	/* Free blocks count */
	u16	bg_free_inodes_count;	/* Free inodes count */
	u16	bg_used_dirs_count;	/* Directories count */
	u16	bg_pad;
	u32	bg_reserved[3];
};

/*
 * Macro-instructions used to manage group descriptors
 */
#ifdef __KERNEL__
# define EXT2_BLOCKS_PER_GROUP(s)	((s)->u.ext2_sb.s_blocks_per_group)
# define EXT2_DESC_PER_BLOCK(s)		((s)->u.ext2_sb.s_desc_per_block)
# define EXT2_INODES_PER_GROUP(s)	((s)->u.ext2_sb.s_inodes_per_group)
#else
# define EXT2_BLOCKS_PER_GROUP(s)	((s)->s_blocks_per_group)
# define EXT2_DESC_PER_BLOCK(s)		(EXT2_BLOCK_SIZE(s) / sizeof (struct ext2_group_desc))
# define EXT2_INODES_PER_GROUP(s)	((s)->s_inodes_per_group)
#endif

/*
 * Constants relative to the data blocks
 */
#define	EXT2_NDIR_BLOCKS		12
#define	EXT2_IND_BLOCK			EXT2_NDIR_BLOCKS
#define	EXT2_DIND_BLOCK			(EXT2_IND_BLOCK + 1)
#define	EXT2_TIND_BLOCK			(EXT2_DIND_BLOCK + 1)
#define	EXT2_N_BLOCKS			(EXT2_TIND_BLOCK + 1)

/*
 * Inode flags
 */
#define	EXT2_SECRM_FL			0x00000001 /* Secure deletion */
#define	EXT2_UNRM_FL			0x00000002 /* Undelete */
#define	EXT2_COMPR_FL			0x00000004 /* Compress file */
#define EXT2_SYNC_FL			0x00000008 /* Synchronous updates */
#define EXT2_IMMUTABLE_FL		0x00000010 /* Immutable file */
#define EXT2_APPEND_FL			0x00000020 /* writes to file may only append */
#define EXT2_NODUMP_FL			0x00000040 /* do not dump file */

/*
 * ioctl commands
 */
#define	EXT2_IOC_GETFLAGS		_IOR('f', 1, long)
#define	EXT2_IOC_SETFLAGS		_IOW('f', 2, long)
#define	EXT2_IOC_GETVERSION		_IOR('v', 1, long)
#define	EXT2_IOC_SETVERSION		_IOW('v', 2, long)

/*
 * Structure of an inode on the disk
 */
struct ext2_inode {
	u16 i_mode;		/* File mode */
	u16 i_uid;		/* Owner Uid */
	u32  i_size;		/* Size in bytes */
	u32  i_atime;		/* Access time */
	u32  i_ctime;		/* Creation time */
	u32  i_mtime;		/* Modification time */
	u32  i_dtime;		/* Deletion Time */
	u16 i_gid;		/* Group Id */
	u16 i_links_count;	/* Links count */
	u32  i_blocks;	/* Blocks count */
	u32  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 */
	u32	i_block[EXT2_N_BLOCKS];/* Pointers to blocks */
	u32	i_version;	/* File version (for NFS) */
	u32	i_file_acl;	/* File ACL */
	u32	i_dir_acl;	/* Directory ACL */
	u32	i_faddr;		/* Fragment address */
	union {
		struct {
			u8	l_i_frag;	/* Fragment number */
			u8	l_i_fsize;	/* Fragment size */
			u16	i_pad1;
			u32	l_i_reserved2[2];
		} 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 */
};

#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_reserved2	osd2.linux2.l_i_reserved2
#endif

#ifdef	__hurd__
#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_mode_high     osd2.hurd2.h_i_mode_high
#define i_author	osd2.hurd2.h_i_author
#endif

#ifdef	__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

/*
 * File system states
 */
#define	EXT2_VALID_FS			0x0001	/* Unmounted cleanly */
#define	EXT2_ERROR_FS			0x0002	/* Errors detected */

/*
 * Mount flags
 */
#define EXT2_MOUNT_CHECK_NORMAL		0x0001	/* Do some more checks */
#define EXT2_MOUNT_CHECK_STRICT		0x0002	/* Do again more checks */
#define EXT2_MOUNT_CHECK		(EXT2_MOUNT_CHECK_NORMAL | \
					 EXT2_MOUNT_CHECK_STRICT)
#define EXT2_MOUNT_GRPID		0x0004	/* Create files with directory's group */
#define EXT2_MOUNT_DEBUG		0x0008	/* Some debugging messages */
#define EXT2_MOUNT_ERRORS_CONT		0x0010	/* Continue on errors */
#define EXT2_MOUNT_ERRORS_RO		0x0020	/* Remount fs ro on errors */
#define EXT2_MOUNT_ERRORS_PANIC		0x0040	/* Panic on errors */
#define EXT2_MOUNT_MINIX_DF		0x0080	/* Mimics the Minix statfs */

#define clear_opt(o, opt)		o &= ~EXT2_MOUNT_##opt
#define set_opt(o, opt)			o |= EXT2_MOUNT_##opt
#define test_opt(sb, opt)		((sb)->u.ext2_sb.s_mount_opt & \
					 EXT2_MOUNT_##opt)
/*
 * Maximal mount counts between two filesystem checks
 */
#define EXT2_DFL_MAX_MNT_COUNT		20	/* Allow 20 mounts */
#define EXT2_DFL_CHECKINTERVAL		0	/* Don't use interval check */

/*
 * Behaviour when detecting errors
 */
#define EXT2_ERRORS_CONTINUE		1	/* Continue execution */
#define EXT2_ERRORS_RO			2	/* Remount fs read-only */
#define EXT2_ERRORS_PANIC		3	/* Panic */
#define EXT2_ERRORS_DEFAULT		EXT2_ERRORS_CONTINUE

/*
 * Structure of the super block
 */
struct ext2_super_block {
	u32	s_inodes_count;		/* Inodes count */
	u32	s_blocks_count;		/* Blocks count */
	u32	s_r_blocks_count;	/* Reserved blocks count */
	u32	s_free_blocks_count;	/* Free blocks count */
	u32	s_free_inodes_count;	/* Free inodes count */
	u32	s_first_data_block;	/* First Data Block */
	u32	s_log_block_size;	/* Block size */
	s32	s_log_frag_size;	/* Fragment size */
	u32	s_blocks_per_group;	/* # Blocks per group */
	u32	s_frags_per_group;	/* # Fragments per group */
	u32	s_inodes_per_group;	/* # Inodes per group */
	u32	s_mtime;		/* Mount time */
	u32	s_wtime;		/* Write time */
	u16	s_mnt_count;		/* Mount count */
	s16	s_max_mnt_count;	/* Maximal mount count */
	u16	s_magic;		/* Magic signature */
	u16	s_state;		/* File system state */
	u16	s_errors;		/* Behaviour when detecting errors */
	u16	s_pad;
	u32	s_lastcheck;		/* time of last check */
	u32	s_checkinterval;	/* max. time between checks */
	u32	s_creator_os;		/* OS */
	u32	s_rev_level;		/* Revision level */
	u16	s_def_resuid;		/* Default uid for reserved blocks */
	u16	s_def_resgid;		/* Default gid for reserved blocks */
	u32	s_reserved[235];	/* Padding to the end of the block */
};

#define EXT2_OS_LINUX		0
#define EXT2_OS_HURD		1
#define EXT2_OS_MASIX		2

#define EXT2_CURRENT_REV	0

#define	EXT2_DEF_RESUID		0
#define	EXT2_DEF_RESGID		0

/*
 * Structure of a directory entry
 */
#define EXT2_NAME_LEN 255

struct ext2_dir_entry {
	u32	inode;			/* Inode number */
	u16	rec_len;		/* Directory entry length */
	u16	name_len;		/* Name length */
	char	name[EXT2_NAME_LEN];	/* File name */
};

/*
 * EXT2_DIR_PAD defines the directory entries boundaries
 *
 * NOTE: It must be a multiple of 4
 */
#define EXT2_DIR_PAD		 	4
#define EXT2_DIR_ROUND 			(EXT2_DIR_PAD - 1)
#define EXT2_DIR_REC_LEN(name_len)	(((name_len) + 8 + EXT2_DIR_ROUND) & \
					 ~EXT2_DIR_ROUND)

#endif	/* _LINUX_EXT2_FS_H */