[linux-block.git] / include / linux / 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

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

#include <linux/ext2_fs_sb.h>

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

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

/*
 * Define EXT2_RESERVATION to reserve data blocks for expanding files
 */
#define EXT2_DEFAULT_RESERVE_BLOCKS     8
/*max window size: 1024(direct blocks) + 3([t,d]indirect blocks) */
#define EXT2_MAX_RESERVE_BLOCKS         1027
#define EXT2_RESERVE_WINDOW_NOT_ALLOCATED 0
/*
 * The second extended file system version
 */
#define EXT2FS_DATE		"95/08/09"
#define EXT2FS_VERSION		"0.5b"

/*
 * Debug code
 */
#ifdef EXT2FS_DEBUG
#	define ext2_debug(f, a...)	{ \
					printk ("EXT2-fs DEBUG (%s, %d): %s:", \
						__FILE__, __LINE__, __func__); \
				  	printk (f, ## a); \
					}
#else
#	define ext2_debug(f, a...)	/**/
#endif

/*
 * Special inode numbers
 */
#define	EXT2_BAD_INO		 1	/* Bad blocks inode */
#define EXT2_ROOT_INO		 2	/* Root inode */
#define EXT2_BOOT_LOADER_INO	 5	/* Boot loader inode */
#define EXT2_UNDEL_DIR_INO	 6	/* Undelete directory inode */

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

static inline struct ext2_sb_info *EXT2_SB(struct super_block *sb)
{
	return sb->s_fs_info;
}

/*
 * 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
#define EXT2_BLOCK_SIZE(s)		((s)->s_blocksize)
#define	EXT2_ADDR_PER_BLOCK(s)		(EXT2_BLOCK_SIZE(s) / sizeof (__u32))
#define EXT2_BLOCK_SIZE_BITS(s)		((s)->s_blocksize_bits)
#define	EXT2_ADDR_PER_BLOCK_BITS(s)	(EXT2_SB(s)->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)

/*
 * 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
#define EXT2_FRAG_SIZE(s)		(EXT2_SB(s)->s_frag_size)
#define EXT2_FRAGS_PER_BLOCK(s)		(EXT2_SB(s)->s_frags_per_block)

/*
 * Structure of a blocks group descriptor
 */
struct ext2_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 */
	__le16	bg_pad;
	__le32	bg_reserved[3];
};

/*
 * Macro-instructions used to manage group descriptors
 */
#define EXT2_BLOCKS_PER_GROUP(s)	(EXT2_SB(s)->s_blocks_per_group)
#define EXT2_DESC_PER_BLOCK(s)		(EXT2_SB(s)->s_desc_per_block)
#define EXT2_INODES_PER_GROUP(s)	(EXT2_SB(s)->s_inodes_per_group)
#define EXT2_DESC_PER_BLOCK_BITS(s)	(EXT2_SB(s)->s_desc_per_block_bits)

/*
 * 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 (GETFLAGS/SETFLAGS)
 */
#define	EXT2_SECRM_FL			FS_SECRM_FL	/* Secure deletion */
#define	EXT2_UNRM_FL			FS_UNRM_FL	/* Undelete */
#define	EXT2_COMPR_FL			FS_COMPR_FL	/* Compress file */
#define EXT2_SYNC_FL			FS_SYNC_FL	/* Synchronous updates */
#define EXT2_IMMUTABLE_FL		FS_IMMUTABLE_FL	/* Immutable file */
#define EXT2_APPEND_FL			FS_APPEND_FL	/* writes to file may only append */
#define EXT2_NODUMP_FL			FS_NODUMP_FL	/* do not dump file */
#define EXT2_NOATIME_FL			FS_NOATIME_FL	/* do not update atime */
/* Reserved for compression usage... */
#define EXT2_DIRTY_FL			FS_DIRTY_FL
#define EXT2_COMPRBLK_FL		FS_COMPRBLK_FL	/* One or more compressed clusters */
#define EXT2_NOCOMP_FL			FS_NOCOMP_FL	/* Don't compress */
#define EXT2_ECOMPR_FL			FS_ECOMPR_FL	/* Compression error */
/* End compression flags --- maybe not all used */	
#define EXT2_BTREE_FL			FS_BTREE_FL	/* btree format dir */
#define EXT2_INDEX_FL			FS_INDEX_FL	/* hash-indexed directory */
#define EXT2_IMAGIC_FL			FS_IMAGIC_FL	/* AFS directory */
#define EXT2_JOURNAL_DATA_FL		FS_JOURNAL_DATA_FL /* Reserved for ext3 */
#define EXT2_NOTAIL_FL			FS_NOTAIL_FL	/* file tail should not be merged */
#define EXT2_DIRSYNC_FL			FS_DIRSYNC_FL	/* dirsync behaviour (directories only) */
#define EXT2_TOPDIR_FL			FS_TOPDIR_FL	/* Top of directory hierarchies*/
#define EXT2_RESERVED_FL		FS_RESERVED_FL	/* reserved for ext2 lib */

#define EXT2_FL_USER_VISIBLE		FS_FL_USER_VISIBLE	/* User visible flags */
#define EXT2_FL_USER_MODIFIABLE		FS_FL_USER_MODIFIABLE	/* User modifiable flags */

/* Flags that should be inherited by new inodes from their parent. */
#define EXT2_FL_INHERITED (EXT2_SECRM_FL | EXT2_UNRM_FL | EXT2_COMPR_FL |\
			   EXT2_SYNC_FL | EXT2_NODUMP_FL |\
			   EXT2_NOATIME_FL | EXT2_COMPRBLK_FL |\
			   EXT2_NOCOMP_FL | EXT2_JOURNAL_DATA_FL |\
			   EXT2_NOTAIL_FL | EXT2_DIRSYNC_FL)

/* Flags that are appropriate for regular files (all but dir-specific ones). */
#define EXT2_REG_FLMASK (~(EXT2_DIRSYNC_FL | EXT2_TOPDIR_FL))

/* Flags that are appropriate for non-directories/regular files. */
#define EXT2_OTHER_FLMASK (EXT2_NODUMP_FL | EXT2_NOATIME_FL)

/* Mask out flags that are inappropriate for the given type of inode. */
static inline __u32 ext2_mask_flags(umode_t mode, __u32 flags)
{
	if (S_ISDIR(mode))
		return flags;
	else if (S_ISREG(mode))
		return flags & EXT2_REG_FLMASK;
	else
		return flags & EXT2_OTHER_FLMASK;
}

/*
 * ioctl commands
 */
#define	EXT2_IOC_GETFLAGS		FS_IOC_GETFLAGS
#define	EXT2_IOC_SETFLAGS		FS_IOC_SETFLAGS
#define	EXT2_IOC_GETVERSION		FS_IOC_GETVERSION
#define	EXT2_IOC_SETVERSION		FS_IOC_SETVERSION
#define	EXT2_IOC_GETRSVSZ		_IOR('f', 5, long)
#define	EXT2_IOC_SETRSVSZ		_IOW('f', 6, long)

/*
 * ioctl commands in 32 bit emulation
 */
#define EXT2_IOC32_GETFLAGS		FS_IOC32_GETFLAGS
#define EXT2_IOC32_SETFLAGS		FS_IOC32_SETFLAGS
#define EXT2_IOC32_GETVERSION		FS_IOC32_GETVERSION
#define EXT2_IOC32_SETVERSION		FS_IOC32_SETVERSION

/*
 * Structure of an inode on the disk
 */
struct ext2_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 {
			__le32  l_i_reserved1;
		} linux1;
		struct {
			__le32  h_i_translator;
		} hurd1;
		struct {
			__le32  m_i_reserved1;
		} masix1;
	} osd1;				/* OS dependent 1 */
	__le32	i_block[EXT2_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 */
			__le16	h_i_mode_high;
			__le16	h_i_uid_high;
			__le16	h_i_gid_high;
			__le32	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 */
};

#define i_size_high	i_dir_acl

#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

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

/*
 * Mount flags
 */
#define EXT2_MOUNT_CHECK		0x000001  /* Do mount-time checks */
#define EXT2_MOUNT_OLDALLOC		0x000002  /* Don't use the new Orlov allocator */
#define EXT2_MOUNT_GRPID		0x000004  /* Create files with directory's group */
#define EXT2_MOUNT_DEBUG		0x000008  /* Some debugging messages */
#define EXT2_MOUNT_ERRORS_CONT		0x000010  /* Continue on errors */
#define EXT2_MOUNT_ERRORS_RO		0x000020  /* Remount fs ro on errors */
#define EXT2_MOUNT_ERRORS_PANIC		0x000040  /* Panic on errors */
#define EXT2_MOUNT_MINIX_DF		0x000080  /* Mimics the Minix statfs */
#define EXT2_MOUNT_NOBH			0x000100  /* No buffer_heads */
#define EXT2_MOUNT_NO_UID32		0x000200  /* Disable 32-bit UIDs */
#define EXT2_MOUNT_XATTR_USER		0x004000  /* Extended user attributes */
#define EXT2_MOUNT_POSIX_ACL		0x008000  /* POSIX Access Control Lists */
#define EXT2_MOUNT_XIP			0x010000  /* Execute in place */
#define EXT2_MOUNT_USRQUOTA		0x020000  /* user quota */
#define EXT2_MOUNT_GRPQUOTA		0x040000  /* group quota */
#define EXT2_MOUNT_RESERVATION		0x080000  /* Preallocation */


#define clear_opt(o, opt)		o &= ~EXT2_MOUNT_##opt
#define set_opt(o, opt)			o |= EXT2_MOUNT_##opt
#define test_opt(sb, opt)		(EXT2_SB(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 {
	__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 */
	__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 */
	__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 */
	__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 */
	__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 */
	__le16	s_def_resuid;		/* Default uid for reserved blocks */
	__le16	s_def_resgid;		/* Default gid for reserved blocks */
	/*
	 * These fields are for EXT2_DYNAMIC_REV superblocks only.
	 *
	 * Note: the difference between the compatible feature set and
	 * 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 */
	__le32	s_feature_incompat; 	/* incompatible feature set */
	__le32	s_feature_ro_compat; 	/* readonly-compatible feature set */
	__u8	s_uuid[16];		/* 128-bit uuid for volume */
	char	s_volume_name[16]; 	/* volume name */
	char	s_last_mounted[64]; 	/* directory where last mounted */
	__le32	s_algorithm_usage_bitmap; /* For compression */
	/*
	 * Performance hints.  Directory preallocation should only
	 * happen if the EXT2_COMPAT_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 */
	__u16	s_padding1;
	/*
	 * Journaling support valid if EXT3_FEATURE_COMPAT_HAS_JOURNAL set.
	 */
	__u8	s_journal_uuid[16];	/* uuid of journal superblock */
	__u32	s_journal_inum;		/* inode number of journal file */
	__u32	s_journal_dev;		/* device number of journal file */
	__u32	s_last_orphan;		/* start of list of inodes to delete */
	__u32	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 */
};

/*
 * Codes for operating systems
 */
#define EXT2_OS_LINUX		0
#define EXT2_OS_HURD		1
#define EXT2_OS_MASIX		2
#define EXT2_OS_FREEBSD		3
#define EXT2_OS_LITES		4

/*
 * Revision levels
 */
#define EXT2_GOOD_OLD_REV	0	/* The good old (original) format */
#define EXT2_DYNAMIC_REV	1 	/* V2 format w/ dynamic inode sizes */

#define EXT2_CURRENT_REV	EXT2_GOOD_OLD_REV
#define EXT2_MAX_SUPP_REV	EXT2_DYNAMIC_REV

#define EXT2_GOOD_OLD_INODE_SIZE 128

/*
 * Feature set definitions
 */

#define EXT2_HAS_COMPAT_FEATURE(sb,mask)			\
	( EXT2_SB(sb)->s_es->s_feature_compat & cpu_to_le32(mask) )
#define EXT2_HAS_RO_COMPAT_FEATURE(sb,mask)			\
	( EXT2_SB(sb)->s_es->s_feature_ro_compat & cpu_to_le32(mask) )
#define EXT2_HAS_INCOMPAT_FEATURE(sb,mask)			\
	( EXT2_SB(sb)->s_es->s_feature_incompat & cpu_to_le32(mask) )
#define EXT2_SET_COMPAT_FEATURE(sb,mask)			\
	EXT2_SB(sb)->s_es->s_feature_compat |= cpu_to_le32(mask)
#define EXT2_SET_RO_COMPAT_FEATURE(sb,mask)			\
	EXT2_SB(sb)->s_es->s_feature_ro_compat |= cpu_to_le32(mask)
#define EXT2_SET_INCOMPAT_FEATURE(sb,mask)			\
	EXT2_SB(sb)->s_es->s_feature_incompat |= cpu_to_le32(mask)
#define EXT2_CLEAR_COMPAT_FEATURE(sb,mask)			\
	EXT2_SB(sb)->s_es->s_feature_compat &= ~cpu_to_le32(mask)
#define EXT2_CLEAR_RO_COMPAT_FEATURE(sb,mask)			\
	EXT2_SB(sb)->s_es->s_feature_ro_compat &= ~cpu_to_le32(mask)
#define EXT2_CLEAR_INCOMPAT_FEATURE(sb,mask)			\
	EXT2_SB(sb)->s_es->s_feature_incompat &= ~cpu_to_le32(mask)

#define EXT2_FEATURE_COMPAT_DIR_PREALLOC	0x0001
#define EXT2_FEATURE_COMPAT_IMAGIC_INODES	0x0002
#define EXT3_FEATURE_COMPAT_HAS_JOURNAL		0x0004
#define EXT2_FEATURE_COMPAT_EXT_ATTR		0x0008
#define EXT2_FEATURE_COMPAT_RESIZE_INO		0x0010
#define EXT2_FEATURE_COMPAT_DIR_INDEX		0x0020
#define EXT2_FEATURE_COMPAT_ANY			0xffffffff

#define EXT2_FEATURE_RO_COMPAT_SPARSE_SUPER	0x0001
#define EXT2_FEATURE_RO_COMPAT_LARGE_FILE	0x0002
#define EXT2_FEATURE_RO_COMPAT_BTREE_DIR	0x0004
#define EXT2_FEATURE_RO_COMPAT_ANY		0xffffffff

#define EXT2_FEATURE_INCOMPAT_COMPRESSION	0x0001
#define EXT2_FEATURE_INCOMPAT_FILETYPE		0x0002
#define EXT3_FEATURE_INCOMPAT_RECOVER		0x0004
#define EXT3_FEATURE_INCOMPAT_JOURNAL_DEV	0x0008
#define EXT2_FEATURE_INCOMPAT_META_BG		0x0010
#define EXT2_FEATURE_INCOMPAT_ANY		0xffffffff

#define EXT2_FEATURE_COMPAT_SUPP	EXT2_FEATURE_COMPAT_EXT_ATTR
#define EXT2_FEATURE_INCOMPAT_SUPP	(EXT2_FEATURE_INCOMPAT_FILETYPE| \
					 EXT2_FEATURE_INCOMPAT_META_BG)
#define EXT2_FEATURE_RO_COMPAT_SUPP	(EXT2_FEATURE_RO_COMPAT_SPARSE_SUPER| \
					 EXT2_FEATURE_RO_COMPAT_LARGE_FILE| \
					 EXT2_FEATURE_RO_COMPAT_BTREE_DIR)
#define EXT2_FEATURE_RO_COMPAT_UNSUPPORTED	~EXT2_FEATURE_RO_COMPAT_SUPP
#define EXT2_FEATURE_INCOMPAT_UNSUPPORTED	~EXT2_FEATURE_INCOMPAT_SUPP

/*
 * Default values for user and/or group using reserved blocks
 */
#define	EXT2_DEF_RESUID		0
#define	EXT2_DEF_RESGID		0

/*
 * Default mount options
 */
#define EXT2_DEFM_DEBUG		0x0001
#define EXT2_DEFM_BSDGROUPS	0x0002
#define EXT2_DEFM_XATTR_USER	0x0004
#define EXT2_DEFM_ACL		0x0008
#define EXT2_DEFM_UID16		0x0010
    /* Not used by ext2, but reserved for use by ext3 */
#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 EXT2_NAME_LEN 255

struct ext2_dir_entry {
	__le32	inode;			/* Inode number */
	__le16	rec_len;		/* Directory entry length */
	__le16	name_len;		/* Name length */
	char	name[EXT2_NAME_LEN];	/* File name */
};

/*
 * The new version of the directory entry.  Since EXT2 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 ext2_dir_entry_2 {
	__le32	inode;			/* Inode number */
	__le16	rec_len;		/* Directory entry length */
	__u8	name_len;		/* Name length */
	__u8	file_type;
	char	name[EXT2_NAME_LEN];	/* File name */
};

/*
 * Ext2 directory file types.  Only the low 3 bits are used.  The
 * other bits are reserved for now.
 */
enum {
	EXT2_FT_UNKNOWN		= 0,
	EXT2_FT_REG_FILE	= 1,
	EXT2_FT_DIR		= 2,
	EXT2_FT_CHRDEV		= 3,
	EXT2_FT_BLKDEV		= 4,
	EXT2_FT_FIFO		= 5,
	EXT2_FT_SOCK		= 6,
	EXT2_FT_SYMLINK		= 7,
	EXT2_FT_MAX
};

/*
 * 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)
#define EXT2_MAX_REC_LEN		((1<<16)-1)

#define EXT2_SB_MAGIC_OFFSET	0x38
#define EXT2_SB_BLOCKS_OFFSET	0x04
#define EXT2_SB_BSIZE_OFFSET	0x18

static inline u64 ext2_image_size(void *ext2_sb)
{
	__u8 *p = ext2_sb;
	if (*(__le16 *)(p + EXT2_SB_MAGIC_OFFSET) != cpu_to_le16(EXT2_SUPER_MAGIC))
		return 0;
	return (u64)le32_to_cpup((__le32 *)(p + EXT2_SB_BLOCKS_OFFSET)) <<
		le32_to_cpup((__le32 *)(p + EXT2_SB_BSIZE_OFFSET));
}

static inline void verify_offsets(void)
{
#define A(x,y) BUILD_BUG_ON(x != offsetof(struct ext2_super_block, y));
	A(EXT2_SB_MAGIC_OFFSET, s_magic);
	A(EXT2_SB_BLOCKS_OFFSET, s_blocks_count);
	A(EXT2_SB_BSIZE_OFFSET, s_log_block_size);
#undef A
}

#endif	/* _LINUX_EXT2_FS_H */
Commit	Line	Data
1da177e4 LT	1	/*
	2	* linux/include/linux/ext2_fs.h
	3	*
	4	* Copyright (C) 1992, 1993, 1994, 1995
	5	* Remy Card (card@masi.ibp.fr)
	6	* Laboratoire MASI - Institut Blaise Pascal
	7	* Universite Pierre et Marie Curie (Paris VI)
	8	*
	9	* from
	10	*
	11	* linux/include/linux/minix_fs.h
	12	*
	13	* Copyright (C) 1991, 1992 Linus Torvalds
	14	*/
	15
	16	#ifndef _LINUX_EXT2_FS_H
	17	#define _LINUX_EXT2_FS_H
	18
	19	#include <linux/types.h>
e18fa700	20	#include <linux/magic.h>
fbcc9e62	21	#include <linux/fs.h>
1da177e4	22
4a165d25 TR	23	#include <linux/ext2_fs_sb.h>
4a165d25 TR	24
1da177e4 LT	25	/*
	26	* The second extended filesystem constants/structures
	27	*/
	28
	29	/*
	30	* Define EXT2FS_DEBUG to produce debug messages
	31	*/
	32	#undef EXT2FS_DEBUG
	33
	34	/*
a686cd89	35	* Define EXT2_RESERVATION to reserve data blocks for expanding files
1da177e4	36	*/
a686cd89 MB	37	#define EXT2_DEFAULT_RESERVE_BLOCKS 8
	38	/max window size: 1024(direct blocks) + 3([t,d]indirect blocks) /
	39	#define EXT2_MAX_RESERVE_BLOCKS 1027
	40	#define EXT2_RESERVE_WINDOW_NOT_ALLOCATED 0
1da177e4 LT	41	/*
	42	* The second extended file system version
	43	*/
	44	#define EXT2FS_DATE "95/08/09"
	45	#define EXT2FS_VERSION "0.5b"
	46
	47	/*
	48	* Debug code
	49	*/
	50	#ifdef EXT2FS_DEBUG
	51	# define ext2_debug(f, a...) { \
	52	printk ("EXT2-fs DEBUG (%s, %d): %s:", \
d5c003b4	53	__FILE__, __LINE__, __func__); \
1da177e4 LT	54	printk (f, ## a); \
	55	}
	56	#else
	57	# define ext2_debug(f, a...) /**/
	58	#endif
	59
	60	/*
	61	* Special inode numbers
	62	*/
	63	#define EXT2_BAD_INO 1 /* Bad blocks inode */
	64	#define EXT2_ROOT_INO 2 /* Root inode */
	65	#define EXT2_BOOT_LOADER_INO 5 /* Boot loader inode */
	66	#define EXT2_UNDEL_DIR_INO 6 /* Undelete directory inode */
	67
	68	/* First non-reserved inode for old ext2 filesystems */
	69	#define EXT2_GOOD_OLD_FIRST_INO 11
	70
1da177e4 LT	71	static inline struct ext2_sb_info EXT2_SB(struct super_block sb)
	72	{
	73	return sb->s_fs_info;
	74	}
1da177e4 LT	75
	76	/*
	77	* Maximal count of links to a file
	78	*/
	79	#define EXT2_LINK_MAX 32000
	80
	81	/*
	82	* Macro-instructions used to manage several block sizes
	83	*/
	84	#define EXT2_MIN_BLOCK_SIZE 1024
	85	#define EXT2_MAX_BLOCK_SIZE 4096
	86	#define EXT2_MIN_BLOCK_LOG_SIZE 10
4a165d25	87	#define EXT2_BLOCK_SIZE(s) ((s)->s_blocksize)
1da177e4	88	#define EXT2_ADDR_PER_BLOCK(s) (EXT2_BLOCK_SIZE(s) / sizeof (__u32))
4a165d25	89	#define EXT2_BLOCK_SIZE_BITS(s) ((s)->s_blocksize_bits)
1da177e4 LT	90	#define EXT2_ADDR_PER_BLOCK_BITS(s) (EXT2_SB(s)->s_addr_per_block_bits)
	91	#define EXT2_INODE_SIZE(s) (EXT2_SB(s)->s_inode_size)
	92	#define EXT2_FIRST_INO(s) (EXT2_SB(s)->s_first_ino)
1da177e4 LT	93
	94	/*
	95	* Macro-instructions used to manage fragments
	96	*/
	97	#define EXT2_MIN_FRAG_SIZE 1024
	98	#define EXT2_MAX_FRAG_SIZE 4096
	99	#define EXT2_MIN_FRAG_LOG_SIZE 10
4a165d25 TR	100	#define EXT2_FRAG_SIZE(s) (EXT2_SB(s)->s_frag_size)
4a165d25 TR	101	#define EXT2_FRAGS_PER_BLOCK(s) (EXT2_SB(s)->s_frags_per_block)
1da177e4 LT	102
	103	/*
	104	* Structure of a blocks group descriptor
	105	*/
	106	struct ext2_group_desc
	107	{
	108	__le32 bg_block_bitmap; /* Blocks bitmap block */
	109	__le32 bg_inode_bitmap; /* Inodes bitmap block */
	110	__le32 bg_inode_table; /* Inodes table block */
	111	__le16 bg_free_blocks_count; /* Free blocks count */
	112	__le16 bg_free_inodes_count; /* Free inodes count */
	113	__le16 bg_used_dirs_count; /* Directories count */
	114	__le16 bg_pad;
	115	__le32 bg_reserved[3];
	116	};
	117
	118	/*
	119	* Macro-instructions used to manage group descriptors
	120	*/
4a165d25 TR	121	#define EXT2_BLOCKS_PER_GROUP(s) (EXT2_SB(s)->s_blocks_per_group)
	122	#define EXT2_DESC_PER_BLOCK(s) (EXT2_SB(s)->s_desc_per_block)
	123	#define EXT2_INODES_PER_GROUP(s) (EXT2_SB(s)->s_inodes_per_group)
	124	#define EXT2_DESC_PER_BLOCK_BITS(s) (EXT2_SB(s)->s_desc_per_block_bits)
1da177e4 LT	125
	126	/*
	127	* Constants relative to the data blocks
	128	*/
	129	#define EXT2_NDIR_BLOCKS 12
	130	#define EXT2_IND_BLOCK EXT2_NDIR_BLOCKS
	131	#define EXT2_DIND_BLOCK (EXT2_IND_BLOCK + 1)
	132	#define EXT2_TIND_BLOCK (EXT2_DIND_BLOCK + 1)
	133	#define EXT2_N_BLOCKS (EXT2_TIND_BLOCK + 1)
	134
	135	/*
36695673 DH	136	* Inode flags (GETFLAGS/SETFLAGS)
	137	*/
	138	#define EXT2_SECRM_FL FS_SECRM_FL /* Secure deletion */
	139	#define EXT2_UNRM_FL FS_UNRM_FL /* Undelete */
	140	#define EXT2_COMPR_FL FS_COMPR_FL /* Compress file */
	141	#define EXT2_SYNC_FL FS_SYNC_FL /* Synchronous updates */
	142	#define EXT2_IMMUTABLE_FL FS_IMMUTABLE_FL /* Immutable file */
	143	#define EXT2_APPEND_FL FS_APPEND_FL /* writes to file may only append */
	144	#define EXT2_NODUMP_FL FS_NODUMP_FL /* do not dump file */
	145	#define EXT2_NOATIME_FL FS_NOATIME_FL /* do not update atime */
1da177e4	146	/* Reserved for compression usage... */
36695673 DH	147	#define EXT2_DIRTY_FL FS_DIRTY_FL
	148	#define EXT2_COMPRBLK_FL FS_COMPRBLK_FL /* One or more compressed clusters */
	149	#define EXT2_NOCOMP_FL FS_NOCOMP_FL /* Don't compress */
	150	#define EXT2_ECOMPR_FL FS_ECOMPR_FL /* Compression error */
1da177e4	151	/* End compression flags --- maybe not all used */
36695673 DH	152	#define EXT2_BTREE_FL FS_BTREE_FL /* btree format dir */
	153	#define EXT2_INDEX_FL FS_INDEX_FL /* hash-indexed directory */
	154	#define EXT2_IMAGIC_FL FS_IMAGIC_FL /* AFS directory */
	155	#define EXT2_JOURNAL_DATA_FL FS_JOURNAL_DATA_FL /* Reserved for ext3 */
	156	#define EXT2_NOTAIL_FL FS_NOTAIL_FL /* file tail should not be merged */
	157	#define EXT2_DIRSYNC_FL FS_DIRSYNC_FL /* dirsync behaviour (directories only) */
	158	#define EXT2_TOPDIR_FL FS_TOPDIR_FL /* Top of directory hierarchies*/
	159	#define EXT2_RESERVED_FL FS_RESERVED_FL /* reserved for ext2 lib */
1da177e4	160
36695673 DH	161	#define EXT2_FL_USER_VISIBLE FS_FL_USER_VISIBLE /* User visible flags */
36695673 DH	162	#define EXT2_FL_USER_MODIFIABLE FS_FL_USER_MODIFIABLE /* User modifiable flags */
1da177e4	163
0e090f1e DG	164	/* Flags that should be inherited by new inodes from their parent. */
0e090f1e DG	165	#define EXT2_FL_INHERITED (EXT2_SECRM_FL \| EXT2_UNRM_FL \| EXT2_COMPR_FL \|\
1cd9f097 TT	166	EXT2_SYNC_FL \| EXT2_NODUMP_FL \|\
1cd9f097 TT	167	EXT2_NOATIME_FL \| EXT2_COMPRBLK_FL \|\
0e090f1e DG	168	EXT2_NOCOMP_FL \| EXT2_JOURNAL_DATA_FL \|\
	169	EXT2_NOTAIL_FL \| EXT2_DIRSYNC_FL)
	170
ef8b6461 DG	171	/* Flags that are appropriate for regular files (all but dir-specific ones). */
	172	#define EXT2_REG_FLMASK (~(EXT2_DIRSYNC_FL \| EXT2_TOPDIR_FL))
	173
	174	/* Flags that are appropriate for non-directories/regular files. */
	175	#define EXT2_OTHER_FLMASK (EXT2_NODUMP_FL \| EXT2_NOATIME_FL)
	176
	177	/* Mask out flags that are inappropriate for the given type of inode. */
	178	static inline __u32 ext2_mask_flags(umode_t mode, __u32 flags)
	179	{
	180	if (S_ISDIR(mode))
	181	return flags;
	182	else if (S_ISREG(mode))
	183	return flags & EXT2_REG_FLMASK;
	184	else
	185	return flags & EXT2_OTHER_FLMASK;
	186	}
	187
1da177e4 LT	188	/*
	189	* ioctl commands
	190	*/
36695673 DH	191	#define EXT2_IOC_GETFLAGS FS_IOC_GETFLAGS
	192	#define EXT2_IOC_SETFLAGS FS_IOC_SETFLAGS
	193	#define EXT2_IOC_GETVERSION FS_IOC_GETVERSION
	194	#define EXT2_IOC_SETVERSION FS_IOC_SETVERSION
a686cd89 MB	195	#define EXT2_IOC_GETRSVSZ _IOR('f', 5, long)
a686cd89 MB	196	#define EXT2_IOC_SETRSVSZ _IOW('f', 6, long)
36695673 DH	197
	198	/*
	199	* ioctl commands in 32 bit emulation
	200	*/
	201	#define EXT2_IOC32_GETFLAGS FS_IOC32_GETFLAGS
	202	#define EXT2_IOC32_SETFLAGS FS_IOC32_SETFLAGS
	203	#define EXT2_IOC32_GETVERSION FS_IOC32_GETVERSION
	204	#define EXT2_IOC32_SETVERSION FS_IOC32_SETVERSION
1da177e4 LT	205
	206	/*
	207	* Structure of an inode on the disk
	208	*/
	209	struct ext2_inode {
	210	__le16 i_mode; /* File mode */
	211	__le16 i_uid; /* Low 16 bits of Owner Uid */
	212	__le32 i_size; /* Size in bytes */
	213	__le32 i_atime; /* Access time */
	214	__le32 i_ctime; /* Creation time */
	215	__le32 i_mtime; /* Modification time */
	216	__le32 i_dtime; /* Deletion Time */
	217	__le16 i_gid; /* Low 16 bits of Group Id */
	218	__le16 i_links_count; /* Links count */
	219	__le32 i_blocks; /* Blocks count */
	220	__le32 i_flags; /* File flags */
	221	union {
	222	struct {
	223	__le32 l_i_reserved1;
	224	} linux1;
	225	struct {
	226	__le32 h_i_translator;
	227	} hurd1;
	228	struct {
	229	__le32 m_i_reserved1;
	230	} masix1;
	231	} osd1; /* OS dependent 1 */
	232	__le32 i_block[EXT2_N_BLOCKS];/* Pointers to blocks */
	233	__le32 i_generation; /* File version (for NFS) */
	234	__le32 i_file_acl; /* File ACL */
	235	__le32 i_dir_acl; /* Directory ACL */
	236	__le32 i_faddr; /* Fragment address */
	237	union {
	238	struct {
	239	__u8 l_i_frag; /* Fragment number */
	240	__u8 l_i_fsize; /* Fragment size */
	241	__u16 i_pad1;
	242	__le16 l_i_uid_high; /* these 2 fields */
	243	__le16 l_i_gid_high; /* were reserved2[0] */
	244	__u32 l_i_reserved2;
	245	} linux2;
	246	struct {
	247	__u8 h_i_frag; /* Fragment number */
	248	__u8 h_i_fsize; /* Fragment size */
	249	__le16 h_i_mode_high;
	250	__le16 h_i_uid_high;
	251	__le16 h_i_gid_high;
	252	__le32 h_i_author;
	253	} hurd2;
	254	struct {
	255	__u8 m_i_frag; /* Fragment number */
	256	__u8 m_i_fsize; /* Fragment size */
	257	__u16 m_pad1;
	258	__u32 m_i_reserved2[2];
	259	} masix2;
	260	} osd2; /* OS dependent 2 */
	261	};
	262
	263	#define i_size_high i_dir_acl
	264
1da177e4 LT	265	#define i_reserved1 osd1.linux1.l_i_reserved1
	266	#define i_frag osd2.linux2.l_i_frag
	267	#define i_fsize osd2.linux2.l_i_fsize
	268	#define i_uid_low i_uid
	269	#define i_gid_low i_gid
	270	#define i_uid_high osd2.linux2.l_i_uid_high
	271	#define i_gid_high osd2.linux2.l_i_gid_high
	272	#define i_reserved2 osd2.linux2.l_i_reserved2
1da177e4 LT	273
	274	/*
	275	* File system states
	276	*/
	277	#define EXT2_VALID_FS 0x0001 /* Unmounted cleanly */
	278	#define EXT2_ERROR_FS 0x0002 /* Errors detected */
	279
	280	/*
	281	* Mount flags
	282	*/
6d79125b CO	283	#define EXT2_MOUNT_CHECK 0x000001 /* Do mount-time checks */
	284	#define EXT2_MOUNT_OLDALLOC 0x000002 /* Don't use the new Orlov allocator */
	285	#define EXT2_MOUNT_GRPID 0x000004 /* Create files with directory's group */
	286	#define EXT2_MOUNT_DEBUG 0x000008 /* Some debugging messages */
	287	#define EXT2_MOUNT_ERRORS_CONT 0x000010 /* Continue on errors */
	288	#define EXT2_MOUNT_ERRORS_RO 0x000020 /* Remount fs ro on errors */
	289	#define EXT2_MOUNT_ERRORS_PANIC 0x000040 /* Panic on errors */
	290	#define EXT2_MOUNT_MINIX_DF 0x000080 /* Mimics the Minix statfs */
	291	#define EXT2_MOUNT_NOBH 0x000100 /* No buffer_heads */
	292	#define EXT2_MOUNT_NO_UID32 0x000200 /* Disable 32-bit UIDs */
	293	#define EXT2_MOUNT_XATTR_USER 0x004000 /* Extended user attributes */
	294	#define EXT2_MOUNT_POSIX_ACL 0x008000 /* POSIX Access Control Lists */
	295	#define EXT2_MOUNT_XIP 0x010000 /* Execute in place */
a686cd89 MB	296	#define EXT2_MOUNT_USRQUOTA 0x020000 /* user quota */
	297	#define EXT2_MOUNT_GRPQUOTA 0x040000 /* group quota */
	298	#define EXT2_MOUNT_RESERVATION 0x080000 /* Preallocation */
8fc2751b	299
1da177e4 LT	300
	301	#define clear_opt(o, opt) o &= ~EXT2_MOUNT_##opt
	302	#define set_opt(o, opt) o \|= EXT2_MOUNT_##opt
	303	#define test_opt(sb, opt) (EXT2_SB(sb)->s_mount_opt & \
	304	EXT2_MOUNT_##opt)
	305	/*
	306	* Maximal mount counts between two filesystem checks
	307	*/
	308	#define EXT2_DFL_MAX_MNT_COUNT 20 /* Allow 20 mounts */
	309	#define EXT2_DFL_CHECKINTERVAL 0 /* Don't use interval check */
	310
	311	/*
	312	* Behaviour when detecting errors
	313	*/
	314	#define EXT2_ERRORS_CONTINUE 1 /* Continue execution */
	315	#define EXT2_ERRORS_RO 2 /* Remount fs read-only */
	316	#define EXT2_ERRORS_PANIC 3 /* Panic */
	317	#define EXT2_ERRORS_DEFAULT EXT2_ERRORS_CONTINUE
	318
	319	/*
	320	* Structure of the super block
	321	*/
	322	struct ext2_super_block {
	323	__le32 s_inodes_count; /* Inodes count */
	324	__le32 s_blocks_count; /* Blocks count */
	325	__le32 s_r_blocks_count; /* Reserved blocks count */
	326	__le32 s_free_blocks_count; /* Free blocks count */
	327	__le32 s_free_inodes_count; /* Free inodes count */
	328	__le32 s_first_data_block; /* First Data Block */
	329	__le32 s_log_block_size; /* Block size */
	330	__le32 s_log_frag_size; /* Fragment size */
	331	__le32 s_blocks_per_group; /* # Blocks per group */
	332	__le32 s_frags_per_group; /* # Fragments per group */
	333	__le32 s_inodes_per_group; /* # Inodes per group */
	334	__le32 s_mtime; /* Mount time */
	335	__le32 s_wtime; /* Write time */
	336	__le16 s_mnt_count; /* Mount count */
	337	__le16 s_max_mnt_count; /* Maximal mount count */
	338	__le16 s_magic; /* Magic signature */
	339	__le16 s_state; /* File system state */
	340	__le16 s_errors; /* Behaviour when detecting errors */
	341	__le16 s_minor_rev_level; /* minor revision level */
	342	__le32 s_lastcheck; /* time of last check */
	343	__le32 s_checkinterval; /* max. time between checks */
	344	__le32 s_creator_os; /* OS */
	345	__le32 s_rev_level; /* Revision level */
	346	__le16 s_def_resuid; /* Default uid for reserved blocks */
	347	__le16 s_def_resgid; /* Default gid for reserved blocks */
	348	/*
	349	* These fields are for EXT2_DYNAMIC_REV superblocks only.
	350	*
	351	* Note: the difference between the compatible feature set and
	352	* the incompatible feature set is that if there is a bit set
	353	* in the incompatible feature set that the kernel doesn't
	354	* know about, it should refuse to mount the filesystem.
	355	*
	356	* e2fsck's requirements are more strict; if it doesn't know
	357	* about a feature in either the compatible or incompatible
	358	* feature set, it must abort and not try to meddle with
	359	* things it doesn't understand...
	360	*/
	361	__le32 s_first_ino; /* First non-reserved inode */
	362	__le16 s_inode_size; /* size of inode structure */
	363	__le16 s_block_group_nr; /* block group # of this superblock */
364	__le32 s_feature_compat; /* compatible feature set */
365	__le32 s_feature_incompat; /* incompatible feature set */
366	__le32 s_feature_ro_compat; /* readonly-compatible feature set */
367	__u8 s_uuid[16]; /* 128-bit uuid for volume */
368	char s_volume_name[16]; /* volume name */
369	char s_last_mounted[64]; /* directory where last mounted */
370	__le32 s_algorithm_usage_bitmap; /* For compression */
371	/*
372	* Performance hints. Directory preallocation should only
373	* happen if the EXT2_COMPAT_PREALLOC flag is on.
374	*/
375	__u8 s_prealloc_blocks; /* Nr of blocks to try to preallocate*/
376	__u8 s_prealloc_dir_blocks; /* Nr to preallocate for dirs */
377	__u16 s_padding1;
378	/*
379	* Journaling support valid if EXT3_FEATURE_COMPAT_HAS_JOURNAL set.
380	*/
381	__u8 s_journal_uuid[16]; /* uuid of journal superblock */
382	__u32 s_journal_inum; /* inode number of journal file */
383	__u32 s_journal_dev; /* device number of journal file */
384	__u32 s_last_orphan; /* start of list of inodes to delete */
385	__u32 s_hash_seed[4]; /* HTREE hash seed */
386	__u8 s_def_hash_version; /* Default hash version to use */
387	__u8 s_reserved_char_pad;
388	__u16 s_reserved_word_pad;
389	__le32 s_default_mount_opts;
390	__le32 s_first_meta_bg; /* First metablock block group */
391	__u32 s_reserved[190]; /* Padding to the end of the block */
392	};
393
394	/*
395	* Codes for operating systems
396	*/
397	#define EXT2_OS_LINUX 0
398	#define EXT2_OS_HURD 1
399	#define EXT2_OS_MASIX 2
400	#define EXT2_OS_FREEBSD 3
401	#define EXT2_OS_LITES 4
402
403	/*
404	* Revision levels
405	*/
406	#define EXT2_GOOD_OLD_REV 0 /* The good old (original) format */
407	#define EXT2_DYNAMIC_REV 1 /* V2 format w/ dynamic inode sizes */
408
409	#define EXT2_CURRENT_REV EXT2_GOOD_OLD_REV
410	#define EXT2_MAX_SUPP_REV EXT2_DYNAMIC_REV
411
412	#define EXT2_GOOD_OLD_INODE_SIZE 128
413
414	/*
415	* Feature set definitions
416	*/
417
418	#define EXT2_HAS_COMPAT_FEATURE(sb,mask) \
419	( EXT2_SB(sb)->s_es->s_feature_compat & cpu_to_le32(mask) )
420	#define EXT2_HAS_RO_COMPAT_FEATURE(sb,mask) \
421	( EXT2_SB(sb)->s_es->s_feature_ro_compat & cpu_to_le32(mask) )
422	#define EXT2_HAS_INCOMPAT_FEATURE(sb,mask) \
423	( EXT2_SB(sb)->s_es->s_feature_incompat & cpu_to_le32(mask) )
424	#define EXT2_SET_COMPAT_FEATURE(sb,mask) \
425	EXT2_SB(sb)->s_es->s_feature_compat \|= cpu_to_le32(mask)
426	#define EXT2_SET_RO_COMPAT_FEATURE(sb,mask) \
427	EXT2_SB(sb)->s_es->s_feature_ro_compat \|= cpu_to_le32(mask)
428	#define EXT2_SET_INCOMPAT_FEATURE(sb,mask) \
429	EXT2_SB(sb)->s_es->s_feature_incompat \|= cpu_to_le32(mask)
430	#define EXT2_CLEAR_COMPAT_FEATURE(sb,mask) \
431	EXT2_SB(sb)->s_es->s_feature_compat &= ~cpu_to_le32(mask)
432	#define EXT2_CLEAR_RO_COMPAT_FEATURE(sb,mask) \
433	EXT2_SB(sb)->s_es->s_feature_ro_compat &= ~cpu_to_le32(mask)
434	#define EXT2_CLEAR_INCOMPAT_FEATURE(sb,mask) \
435	EXT2_SB(sb)->s_es->s_feature_incompat &= ~cpu_to_le32(mask)
436
437	#define EXT2_FEATURE_COMPAT_DIR_PREALLOC 0x0001
438	#define EXT2_FEATURE_COMPAT_IMAGIC_INODES 0x0002
439	#define EXT3_FEATURE_COMPAT_HAS_JOURNAL 0x0004
440	#define EXT2_FEATURE_COMPAT_EXT_ATTR 0x0008
441	#define EXT2_FEATURE_COMPAT_RESIZE_INO 0x0010
442	#define EXT2_FEATURE_COMPAT_DIR_INDEX 0x0020
443	#define EXT2_FEATURE_COMPAT_ANY 0xffffffff
444
445	#define EXT2_FEATURE_RO_COMPAT_SPARSE_SUPER 0x0001
446	#define EXT2_FEATURE_RO_COMPAT_LARGE_FILE 0x0002
447	#define EXT2_FEATURE_RO_COMPAT_BTREE_DIR 0x0004
448	#define EXT2_FEATURE_RO_COMPAT_ANY 0xffffffff
449
450	#define EXT2_FEATURE_INCOMPAT_COMPRESSION 0x0001
451	#define EXT2_FEATURE_INCOMPAT_FILETYPE 0x0002
452	#define EXT3_FEATURE_INCOMPAT_RECOVER 0x0004
453	#define EXT3_FEATURE_INCOMPAT_JOURNAL_DEV 0x0008
454	#define EXT2_FEATURE_INCOMPAT_META_BG 0x0010
455	#define EXT2_FEATURE_INCOMPAT_ANY 0xffffffff
456
457	#define EXT2_FEATURE_COMPAT_SUPP EXT2_FEATURE_COMPAT_EXT_ATTR
458	#define EXT2_FEATURE_INCOMPAT_SUPP (EXT2_FEATURE_INCOMPAT_FILETYPE\| \
459	EXT2_FEATURE_INCOMPAT_META_BG)
460	#define EXT2_FEATURE_RO_COMPAT_SUPP (EXT2_FEATURE_RO_COMPAT_SPARSE_SUPER\| \
461	EXT2_FEATURE_RO_COMPAT_LARGE_FILE\| \
462	EXT2_FEATURE_RO_COMPAT_BTREE_DIR)
463	#define EXT2_FEATURE_RO_COMPAT_UNSUPPORTED ~EXT2_FEATURE_RO_COMPAT_SUPP
464	#define EXT2_FEATURE_INCOMPAT_UNSUPPORTED ~EXT2_FEATURE_INCOMPAT_SUPP
465
466	/*
467	* Default values for user and/or group using reserved blocks
468	*/
469	#define EXT2_DEF_RESUID 0
470	#define EXT2_DEF_RESGID 0
471
472	/*
473	* Default mount options
474	*/
475	#define EXT2_DEFM_DEBUG 0x0001
476	#define EXT2_DEFM_BSDGROUPS 0x0002
477	#define EXT2_DEFM_XATTR_USER 0x0004
478	#define EXT2_DEFM_ACL 0x0008
479	#define EXT2_DEFM_UID16 0x0010
480	/* Not used by ext2, but reserved for use by ext3 */
481	#define EXT3_DEFM_JMODE 0x0060
482	#define EXT3_DEFM_JMODE_DATA 0x0020
483	#define EXT3_DEFM_JMODE_ORDERED 0x0040
484	#define EXT3_DEFM_JMODE_WBACK 0x0060
485
486	/*
487	* Structure of a directory entry
488	*/
489	#define EXT2_NAME_LEN 255
490
491	struct ext2_dir_entry {
492	__le32 inode; /* Inode number */
493	__le16 rec_len; /* Directory entry length */
494	__le16 name_len; /* Name length */
495	char name[EXT2_NAME_LEN]; /* File name */
496	};
497
498	/*
499	* The new version of the directory entry. Since EXT2 structures are
500	* stored in intel byte order, and the name_len field could never be
501	* bigger than 255 chars, it's safe to reclaim the extra byte for the
502	* file_type field.
503	*/
504	struct ext2_dir_entry_2 {
505	__le32 inode; /* Inode number */
506	__le16 rec_len; /* Directory entry length */
507	__u8 name_len; /* Name length */
508	__u8 file_type;
509	char name[EXT2_NAME_LEN]; /* File name */
510	};
511
512	/*
513	* Ext2 directory file types. Only the low 3 bits are used. The
514	* other bits are reserved for now.
515	*/
516	enum {
ad888a1f JB	517	EXT2_FT_UNKNOWN = 0,
	518	EXT2_FT_REG_FILE = 1,
	519	EXT2_FT_DIR = 2,
	520	EXT2_FT_CHRDEV = 3,
	521	EXT2_FT_BLKDEV = 4,
	522	EXT2_FT_FIFO = 5,
	523	EXT2_FT_SOCK = 6,
	524	EXT2_FT_SYMLINK = 7,
1da177e4 LT	525	EXT2_FT_MAX
	526	};
	527
	528	/*
	529	* EXT2_DIR_PAD defines the directory entries boundaries
	530	*
	531	* NOTE: It must be a multiple of 4
	532	*/
	533	#define EXT2_DIR_PAD 4
	534	#define EXT2_DIR_ROUND (EXT2_DIR_PAD - 1)
	535	#define EXT2_DIR_REC_LEN(name_len) (((name_len) + 8 + EXT2_DIR_ROUND) & \
	536	~EXT2_DIR_ROUND)
89910ccc	537	#define EXT2_MAX_REC_LEN ((1<<16)-1)
1da177e4	538
39429c5e AV	539	#define EXT2_SB_MAGIC_OFFSET 0x38
	540	#define EXT2_SB_BLOCKS_OFFSET 0x04
	541	#define EXT2_SB_BSIZE_OFFSET 0x18
	542
	543	static inline u64 ext2_image_size(void *ext2_sb)
	544	{
	545	__u8 *p = ext2_sb;
	546	if ((__le16 )(p + EXT2_SB_MAGIC_OFFSET) != cpu_to_le16(EXT2_SUPER_MAGIC))
	547	return 0;
	548	return (u64)le32_to_cpup((__le32 *)(p + EXT2_SB_BLOCKS_OFFSET)) <<
	549	le32_to_cpup((__le32 *)(p + EXT2_SB_BSIZE_OFFSET));
	550	}
	551
	552	static inline void verify_offsets(void)
	553	{
	554	#define A(x,y) BUILD_BUG_ON(x != offsetof(struct ext2_super_block, y));
	555	A(EXT2_SB_MAGIC_OFFSET, s_magic);
	556	A(EXT2_SB_BLOCKS_OFFSET, s_blocks_count);
	557	A(EXT2_SB_BSIZE_OFFSET, s_log_block_size);
	558	#undef A
	559	}
	560
1da177e4	561	#endif /* _LINUX_EXT2_FS_H */