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 *  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

#include <ext2fs/ext2_types.h>		/* Changed from linux/types.h */

#ifndef __GNUC_PREREQ
#if defined(__GNUC__) && defined(__GNUC_MINOR__)
#define __GNUC_PREREQ(maj, min) \
	((__GNUC__ << 16) + __GNUC_MINOR__ >= ((maj) << 16) + (min))
#else
#define __GNUC_PREREQ(maj, min) 0
#endif
#endif

#ifndef __nonstring
#ifdef __has_attribute
#if __has_attribute(__nonstring__)
#define __nonstring                    __attribute__((__nonstring__))
#else
#define __nonstring
#endif /* __has_attribute(__nonstring__) */
#else
# define __nonstring
#endif /* __has_attribute */
#endif /* __nonstring */

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

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

/*
 * Define EXT2_PREALLOCATE to preallocate data blocks for expanding files
 */
#define EXT2_PREALLOCATE
#define EXT2_DEFAULT_PREALLOC_BLOCKS	8

/*
 * The second extended file system version
 */
#define EXT2FS_DATE		"95/08/09"
#define EXT2FS_VERSION		"0.5b"

/*
 * Special inode numbers
 */
#define EXT2_BAD_INO		 1	/* Bad blocks inode */
#define EXT2_ROOT_INO		 2	/* Root inode */
#define EXT4_USR_QUOTA_INO	 3	/* User quota inode */
#define EXT4_GRP_QUOTA_INO	 4	/* Group quota inode */
#define EXT2_BOOT_LOADER_INO	 5	/* Boot loader inode */
#define EXT2_UNDEL_DIR_INO	 6	/* Undelete directory inode */
#define EXT2_RESIZE_INO		 7	/* Reserved group descriptors inode */
#define EXT2_JOURNAL_INO	 8	/* Journal inode */
#define EXT2_EXCLUDE_INO	 9	/* The "exclude" inode, for snapshots */
#define EXT4_REPLICA_INO	10	/* Used by non-upstream feature */

/* First non-reserved inode for old ext2 filesystems */
#define EXT2_GOOD_OLD_FIRST_INO	11

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

#ifdef __KERNEL__
#define EXT2_SB(sb)	(&((sb)->u.ext2_sb))
#else
/* Assume that user mode programs are passing in an ext2fs superblock, not
 * a kernel struct super_block.  This will allow us to call the feature-test
 * macros from user land. */
#define EXT2_SB(sb)	(sb)
#endif

/*
 * Maximal count of links to a file
 */
#define EXT2_LINK_MAX		65000

/*
 * Macro-instructions used to manage several block sizes
 */
#define EXT2_MIN_BLOCK_LOG_SIZE		10	/* 1024 */
#define EXT2_MAX_BLOCK_LOG_SIZE		16	/* 65536 */
#define EXT2_MIN_BLOCK_SIZE	(1 << EXT2_MIN_BLOCK_LOG_SIZE)
#define EXT2_MAX_BLOCK_SIZE	(1 << EXT2_MAX_BLOCK_LOG_SIZE)
#ifdef __KERNEL__
#define EXT2_BLOCK_SIZE(s)	((s)->s_blocksize)
#define EXT2_BLOCK_SIZE_BITS(s)	((s)->s_blocksize_bits)
#define EXT2_ADDR_PER_BLOCK_BITS(s)	(EXT2_SB(s)->addr_per_block_bits)
#define EXT2_INODE_SIZE(s)	(EXT2_SB(s)->s_inode_size)
#define EXT2_FIRST_INO(s)	(EXT2_SB(s)->s_first_ino)
#else
#define EXT2_BLOCK_SIZE(s)	(EXT2_MIN_BLOCK_SIZE << (s)->s_log_block_size)
#define EXT2_BLOCK_SIZE_BITS(s)	((s)->s_log_block_size + 10)
#define EXT2_INODE_SIZE(s)	(((s)->s_rev_level == EXT2_GOOD_OLD_REV) ? \
				 EXT2_GOOD_OLD_INODE_SIZE : (s)->s_inode_size)
#define EXT2_FIRST_INO(s)	(((s)->s_rev_level == EXT2_GOOD_OLD_REV) ? \
				 EXT2_GOOD_OLD_FIRST_INO : (s)->s_first_ino)
#endif
#define EXT2_ADDR_PER_BLOCK(s)	(EXT2_BLOCK_SIZE(s) / sizeof(__u32))

/*
 * Macro-instructions used to manage allocation clusters
 */
#define EXT2_MIN_CLUSTER_LOG_SIZE	EXT2_MIN_BLOCK_LOG_SIZE
#define EXT2_MAX_CLUSTER_LOG_SIZE	29	/* 512MB  */
#define EXT2_MIN_CLUSTER_SIZE		EXT2_MIN_BLOCK_SIZE
#define EXT2_MAX_CLUSTER_SIZE		(1 << EXT2_MAX_CLUSTER_LOG_SIZE)
#define EXT2_CLUSTER_SIZE(s)		(EXT2_MIN_BLOCK_SIZE << \
						(s)->s_log_cluster_size)
#define EXT2_CLUSTER_SIZE_BITS(s)	((s)->s_log_cluster_size + 10)

/*
 * Macro-instructions used to manage fragments
 *
 * Note: for backwards compat