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+/* vi: set sw=4 ts=4: */
+/*
+ * 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)
+ *
+ * Copyright (C) 1991, 1992 Linus Torvalds
+ */
+
+#ifndef LINUX_EXT2_FS_H
+#define LINUX_EXT2_FS_H 1
+
+/*
+ * Special inode 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_RESIZE_INO 7 /* Reserved group descriptors inode */
+#define EXT2_JOURNAL_INO 8 /* Journal inode */
+
+/* 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
+
+/* 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)
+
+/*
+ * Maximal count of links to a file
+ */
+#define EXT2_LINK_MAX 32000
+
+/*
+ * 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)
+#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)
+#define EXT2_ADDR_PER_BLOCK(s) (EXT2_BLOCK_SIZE(s) / sizeof(uint32_t))
+
+/*
+ * Macro-instructions used to manage fragments
+ */
+#define EXT2_MIN_FRAG_SIZE EXT2_MIN_BLOCK_SIZE
+#define EXT2_MAX_FRAG_SIZE EXT2_MAX_BLOCK_SIZE
+#define EXT2_MIN_FRAG_LOG_SIZE EXT2_MIN_BLOCK_LOG_SIZE
+#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))
+
+/*
+ * ACL structures
+ */
+struct ext2_acl_header { /* Header of Access Control Lists */
+ uint32_t aclh_size;
+ uint32_t aclh_file_count;
+ uint32_t aclh_acle_count;
+ uint32_t aclh_first_acle;
+};
+
+struct ext2_acl_entry { /* Access Control List Entry */
+ uint32_t acle_size;
+ uint16_t acle_perms; /* Access permissions */
+ uint16_t acle_type; /* Type of entry */
+ uint16_t acle_tag; /* User or group identity */
+ uint16_t acle_pad1;
+ uint32_t acle_next; /* Pointer on next entry for the */
+ /* same inode or on next free entry */
+};
+
+/*
+ * Structure of a blocks group descriptor
+ */
+struct ext2_group_desc {
+ uint32_t bg_block_bitmap; /* Blocks bitmap block */
+ uint32_t bg_inode_bitmap; /* Inodes bitmap block */
+ uint32_t bg_inode_table; /* Inodes table block */
+ uint16_t bg_free_blocks_count; /* Free blocks count */
+ uint16_t bg_free_inodes_count; /* Free inodes count */
+ uint16_t bg_used_dirs_count; /* Directories count */
+ uint16_t bg_pad;
+ uint32_t bg_reserved[3];
+};
+
+/*
+ * Data structures used by the directory indexing feature
+ *
+ * Note: all of the multibyte integer fields are little endian.
+ */
+
+/*
+ * Note: dx_root_info is laid out so that if it should somehow get
+ * overlaid by a dirent the two low bits of the hash version will be
+ * zero. Therefore, the hash version mod 4 should never be 0.
+ * Sincerely, the paranoia department.
+ */
+struct ext2_dx_root_info {
+ uint32_t reserved_zero;
+ uint8_t hash_version; /* 0 now, 1 at release */
+ uint8_t info_length; /* 8 */
+ uint8_t indirect_levels;
+ uint8_t unused_flags;
+};
+
+#define EXT2_HASH_LEGACY 0
+#define EXT2_HASH_HALF_MD4 1
+#define EXT2_HASH_TEA 2
+
+#define EXT2_HASH_FLAG_INCOMPAT 0x1
+
+struct ext2_dx_entry {
+ uint32_t hash;
+ uint32_t block;
+};
+
+struct ext2_dx_countlimit {
+ uint16_t limit;
+ uint16_t count;
+};
+
+
+/*
+ * Macro-instructions used to manage group descriptors
+ */
+#define EXT2_BLOCKS_PER_GROUP(s) (EXT2_SB(s)->s_blocks_per_group)
+#define EXT2_INODES_PER_GROUP(s) (EXT2_SB(s)->s_inodes_per_group)
+#define EXT2_INODES_PER_BLOCK(s) (EXT2_BLOCK_SIZE(s)/EXT2_INODE_SIZE(s))
+/* limits imposed by 16-bit value gd_free_{blocks,inode}_count */
+#define EXT2_MAX_BLOCKS_PER_GROUP(s) ((1 << 16) - 8)
+#define EXT2_MAX_INODES_PER_GROUP(s) ((1 << 16) - EXT2_INODES_PER_BLOCK(s))
+#define EXT2_DESC_PER_BLOCK(s) (EXT2_BLOCK_SIZE(s) / sizeof (struct ext2_group_desc))
+
+/*
+ * 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 */
+#define EXT2_NOATIME_FL 0x00000080 /* do not update atime */
+/* Reserved for compression usage... */
+#define EXT2_DIRTY_FL 0x00000100
+#define EXT2_COMPRBLK_FL 0x00000200 /* One or more compressed clusters */
+#define EXT2_NOCOMPR_FL 0x00000400 /* Access raw compressed data */
+#define EXT2_ECOMPR_FL 0x00000800 /* Compression error */
+/* End compression flags --- maybe not all used */
+#define EXT2_BTREE_FL 0x00001000 /* btree format dir */
+#define EXT2_INDEX_FL 0x00001000 /* hash-indexed directory */
+#define EXT2_IMAGIC_FL 0x00002000
+#define EXT3_JOURNAL_DATA_FL 0x00004000 /* file data should be journaled */
+#define EXT2_NOTAIL_FL 0x00008000 /* file tail should not be merged */
+#define EXT2_DIRSYNC_FL 0x00010000 /* Synchronous directory modifications */
+#define EXT2_TOPDIR_FL 0x00020000 /* Top of directory hierarchies*/
+#define EXT3_EXTENTS_FL 0x00080000 /* Inode uses extents */
+#define EXT2_RESERVED_FL 0x80000000 /* reserved for ext2 lib */
+
+#define EXT2_FL_USER_VISIBLE 0x0003DFFF /* User visible flags */
+#define EXT2_FL_USER_MODIFIABLE 0x000080FF /* User modifiable flags */
+
+/*
+ * 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 {
+ uint16_t i_mode; /* File mode */
+ uint16_t i_uid; /* Low 16 bits of Owner Uid */
+ uint32_t i_size; /* Size in bytes */
+ uint32_t i_atime; /* Access time */
+ uint32_t i_ctime; /* Creation time */
+ uint32_t i_mtime; /* Modification time */
+ uint32_t i_dtime; /* Deletion Time */
+ uint16_t i_gid; /* Low 16 bits of Group Id */
+ uint16_t i_links_count; /* Links count */
+ uint32_t i_blocks; /* Blocks count */
+ uint32_t i_flags; /* File flags */
+ union {
+ struct {
+ uint32_t l_i_reserved1;
+ } linux1;
+ struct {
+ uint32_t h_i_translator;
+ } hurd1;
+ struct {
+ uint32_t m_i_reserved1;
+ } masix1;
+ } osd1; /* OS dependent 1 */
+ uint32_t i_block[EXT2_N_BLOCKS];/* Pointers to blocks */
+ uint32_t i_generation; /* File version (for NFS) */
+ uint32_t i_file_acl; /* File ACL */
+ uint32_t i_dir_acl; /* Directory ACL */
+ uint32_t i_faddr; /* Fragment address */
+ union {
+ struct {
+ uint8_t l_i_frag; /* Fragment number */
+ uint8_t l_i_fsize; /* Fragment size */
+ uint16_t i_pad1;
+ uint16_t l_i_uid_high; /* these 2 fields */
+ uint16_t l_i_gid_high; /* were reserved2[0] */
+ uint32_t l_i_reserved2;
+ } linux2;
+ struct {
+ uint8_t h_i_frag; /* Fragment number */
+ uint8_t h_i_fsize; /* Fragment size */
+ uint16_t h_i_mode_high;
+ uint16_t h_i_uid_high;
+ uint16_t h_i_gid_high;
+ uint32_t h_i_author;
+ } hurd2;
+ struct {
+ uint8_t m_i_frag; /* Fragment number */
+ uint8_t m_i_fsize; /* Fragment size */
+ uint16_t m_pad1;
+ uint32_t m_i_reserved2[2];
+ } masix2;
+ } osd2; /* OS dependent 2 */
+};
+
+/*
+ * Permanent part of an large inode on the disk
+ */
+struct ext2_inode_large {
+ uint16_t i_mode; /* File mode */
+ uint16_t i_uid; /* Low 16 bits of Owner Uid */
+ uint32_t i_size; /* Size in bytes */
+ uint32_t i_atime; /* Access time */
+ uint32_t i_ctime; /* Creation time */
+ uint32_t i_mtime; /* Modification time */
+ uint32_t i_dtime; /* Deletion Time */
+ uint16_t i_gid; /* Low 16 bits of Group Id */
+ uint16_t i_links_count; /* Links count */
+ uint32_t i_blocks; /* Blocks count */
+ uint32_t i_flags; /* File flags */
+ union {
+ struct {
+ uint32_t l_i_reserved1;
+ } linux1;
+ struct {
+ uint32_t h_i_translator;
+ } hurd1;
+ struct {
+ uint32_t m_i_reserved1;
+ } masix1;
+ } osd1; /* OS dependent 1 */
+ uint32_t i_block[EXT2_N_BLOCKS];/* Pointers to blocks */
+ uint32_t i_generation; /* File version (for NFS) */
+ uint32_t i_file_acl; /* File ACL */
+ uint32_t i_dir_acl; /* Directory ACL */
+ uint32_t i_faddr; /* Fragment address */
+ union {
+ struct {
+ uint8_t l_i_frag; /* Fragment number */
+ uint8_t l_i_fsize; /* Fragment size */
+ uint16_t i_pad1;
+ uint16_t l_i_uid_high; /* these 2 fields */
+ uint16_t l_i_gid_high; /* were reserved2[0] */
+ uint32_t l_i_reserved2;
+ } linux2;
+ struct {
+ uint8_t h_i_frag; /* Fragment number */
+ uint8_t h_i_fsize; /* Fragment size */
+ uint16_t h_i_mode_high;
+ uint16_t h_i_uid_high;
+ uint16_t h_i_gid_high;
+ uint32_t h_i_author;
+ } hurd2;
+ struct {
+ uint8_t m_i_frag; /* Fragment number */
+ uint8_t m_i_fsize; /* Fragment size */
+ uint16_t m_pad1;
+ uint32_t m_i_reserved2[2];
+ } masix2;
+ } osd2; /* OS dependent 2 */
+ uint16_t i_extra_isize;
+ uint16_t i_pad1;
+};
+
+#define i_size_high i_dir_acl
+
+/*
+ * File system states
+ */
+#define EXT2_VALID_FS 0x0001 /* Unmounted cleanly */
+#define EXT2_ERROR_FS 0x0002 /* Errors detected */
+
+/*
+ * Mount flags
+ */
+#define EXT2_MOUNT_CHECK 0x0001 /* Do mount-time checks */
+#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 EXT2_MOUNT_NO_UID32 0x0200 /* Disable 32-bit UIDs */
+
+#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 {
+ uint32_t s_inodes_count; /* Inodes count */
+ uint32_t s_blocks_count; /* Blocks count */
+ uint32_t s_r_blocks_count; /* Reserved blocks count */
+ uint32_t s_free_blocks_count; /* Free blocks count */
+ uint32_t s_free_inodes_count; /* Free inodes count */
+ uint32_t s_first_data_block; /* First Data Block */
+ uint32_t s_log_block_size; /* Block size */
+ int32_t s_log_frag_size; /* Fragment size */
+ uint32_t s_blocks_per_group; /* # Blocks per group */
+ uint32_t s_frags_per_group; /* # Fragments per group */
+ uint32_t s_inodes_per_group; /* # Inodes per group */
+ uint32_t s_mtime; /* Mount time */
+ uint32_t s_wtime; /* Write time */
+ uint16_t s_mnt_count; /* Mount count */
+ int16_t s_max_mnt_count; /* Maximal mount count */
+ uint16_t s_magic; /* Magic signature */
+ uint16_t s_state; /* File system state */
+ uint16_t s_errors; /* Behaviour when detecting errors */
+ uint16_t s_minor_rev_level; /* minor revision level */
+ uint32_t s_lastcheck; /* time of last check */
+ uint32_t s_checkinterval; /* max. time between checks */
+ uint32_t s_creator_os; /* OS */
+ uint32_t s_rev_level; /* Revision level */
+ uint16_t s_def_resuid; /* Default uid for reserved blocks */
+ uint16_t 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...
+ */
+ uint32_t s_first_ino; /* First non-reserved inode */
+ uint16_t s_inode_size; /* size of inode structure */
+ uint16_t s_block_group_nr; /* block group # of this superblock */
+ uint32_t s_feature_compat; /* compatible feature set */
+ uint32_t s_feature_incompat; /* incompatible feature set */
+ uint32_t s_feature_ro_compat; /* readonly-compatible feature set */
+ uint8_t s_uuid[16]; /* 128-bit uuid for volume */
+ char s_volume_name[16]; /* volume name */
+ char s_last_mounted[64]; /* directory where last mounted */
+ uint32_t s_algorithm_usage_bitmap; /* For compression */
+ /*
+ * Performance hints. Directory preallocation should only
+ * happen if the EXT2_FEATURE_COMPAT_DIR_PREALLOC flag is on.
+ */
+ uint8_t s_prealloc_blocks; /* Nr of blocks to try to preallocate*/
+ uint8_t s_prealloc_dir_blocks; /* Nr to preallocate for dirs */
+ uint16_t s_reserved_gdt_blocks; /* Per group table for online growth */
+ /*
+ * Journaling support valid if EXT2_FEATURE_COMPAT_HAS_JOURNAL set.
+ */
+ uint8_t s_journal_uuid[16]; /* uuid of journal superblock */
+ uint32_t s_journal_inum; /* inode number of journal file */
+ uint32_t s_journal_dev; /* device number of journal file */
+ uint32_t s_last_orphan; /* start of list of inodes to delete */
+ uint32_t s_hash_seed[4]; /* HTREE hash seed */
+ uint8_t s_def_hash_version; /* Default hash version to use */
+ uint8_t s_jnl_backup_type; /* Default type of journal backup */
+ uint16_t s_reserved_word_pad;
+ uint32_t s_default_mount_opts;
+ uint32_t s_first_meta_bg; /* First metablock group */
+ uint32_t s_mkfs_time; /* When the filesystem was created */
+ uint32_t s_jnl_blocks[17]; /* Backup of the journal inode */
+ uint32_t s_reserved[172]; /* 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
+
+/*
+ * Journal inode backup types
+ */
+#define EXT3_JNL_BACKUP_BLOCKS 1
+
+/*
+ * Feature set definitions
+ */
+
+#define EXT2_HAS_COMPAT_FEATURE(sb,mask) \
+ ( EXT2_SB(sb)->s_feature_compat & (mask) )
+#define EXT2_HAS_RO_COMPAT_FEATURE(sb,mask) \
+ ( EXT2_SB(sb)->s_feature_ro_compat & (mask) )
+#define EXT2_HAS_INCOMPAT_FEATURE(sb,mask) \
+ ( EXT2_SB(sb)->s_feature_incompat & (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_RO_COMPAT_SPARSE_SUPER 0x0001
+#define EXT2_FEATURE_RO_COMPAT_LARGE_FILE 0x0002
+/* #define EXT2_FEATURE_RO_COMPAT_BTREE_DIR 0x0004 not used */
+
+#define EXT2_FEATURE_INCOMPAT_COMPRESSION 0x0001
+#define EXT2_FEATURE_INCOMPAT_FILETYPE 0x0002
+#define EXT3_FEATURE_INCOMPAT_RECOVER 0x0004 /* Needs recovery */
+#define EXT3_FEATURE_INCOMPAT_JOURNAL_DEV 0x0008 /* Journal device */
+#define EXT2_FEATURE_INCOMPAT_META_BG 0x0010
+#define EXT3_FEATURE_INCOMPAT_EXTENTS 0x0040
+
+
+#define EXT2_FEATURE_COMPAT_SUPP 0
+#define EXT2_FEATURE_INCOMPAT_SUPP (EXT2_FEATURE_INCOMPAT_FILETYPE)
+#define EXT2_FEATURE_RO_COMPAT_SUPP (EXT2_FEATURE_RO_COMPAT_SPARSE_SUPER| \
+ EXT2_FEATURE_RO_COMPAT_LARGE_FILE| \
+ EXT2_FEATURE_RO_COMPAT_BTREE_DIR)
+
+/*
+ * 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
+#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 {
+ uint32_t inode; /* Inode number */
+ uint16_t rec_len; /* Directory entry length */
+ uint16_t 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 {
+ uint32_t inode; /* Inode number */
+ uint16_t rec_len; /* Directory entry length */
+ uint8_t name_len; /* Name length */
+ uint8_t 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.
+ */
+#define EXT2_FT_UNKNOWN 0
+#define EXT2_FT_REG_FILE 1
+#define EXT2_FT_DIR 2
+#define EXT2_FT_CHRDEV 3
+#define EXT2_FT_BLKDEV 4
+#define EXT2_FT_FIFO 5
+#define EXT2_FT_SOCK 6
+#define EXT2_FT_SYMLINK 7
+
+#define EXT2_FT_MAX 8
+
+/*
+ * 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