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authorLinus Torvalds <torvalds@ppc970.osdl.org>2005-04-17 02:20:36 +0400
committerLinus Torvalds <torvalds@ppc970.osdl.org>2005-04-17 02:20:36 +0400
commit1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 (patch)
tree0bba044c4ce775e45a88a51686b5d9f90697ea9d /include/linux/ext2_fs.h
downloadlinux-1da177e4c3f41524e886b7f1b8a0c1fc7321cac2.tar.xz
Linux-2.6.12-rc2
Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
Diffstat (limited to 'include/linux/ext2_fs.h')
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diff --git a/include/linux/ext2_fs.h b/include/linux/ext2_fs.h
new file mode 100644
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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 <linux/types.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_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"
+
+/*
+ * Debug code
+ */
+#ifdef EXT2FS_DEBUG
+# define ext2_debug(f, a...) { \
+ printk ("EXT2-fs DEBUG (%s, %d): %s:", \
+ __FILE__, __LINE__, __FUNCTION__); \
+ 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
+
+/*
+ * The second extended file system magic number
+ */
+#define EXT2_SUPER_MAGIC 0xEF53
+
+#ifdef __KERNEL__
+static inline struct ext2_sb_info *EXT2_SB(struct super_block *sb)
+{
+ return sb->s_fs_info;
+}
+#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 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_ADDR_PER_BLOCK(s) (EXT2_BLOCK_SIZE(s) / sizeof (__u32))
+#ifdef __KERNEL__
+# define EXT2_BLOCK_SIZE_BITS(s) ((s)->s_blocksize_bits)
+#else
+# define EXT2_BLOCK_SIZE_BITS(s) ((s)->s_log_block_size + 10)
+#endif
+#ifdef __KERNEL__
+#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)
+#else
+#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
+
+/*
+ * 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) (EXT2_SB(s)->s_frag_size)
+# define EXT2_FRAGS_PER_BLOCK(s) (EXT2_SB(s)->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
+
+/*
+ * 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
+ */
+#ifdef __KERNEL__
+# 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)
+#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 */
+#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_NOCOMP_FL 0x00000400 /* Don't compress */
+#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 /* AFS directory */
+#define EXT2_JOURNAL_DATA_FL 0x00004000 /* Reserved for ext3 */
+#define EXT2_NOTAIL_FL 0x00008000 /* file tail should not be merged */
+#define EXT2_DIRSYNC_FL 0x00010000 /* dirsync behaviour (directories only) */
+#define EXT2_TOPDIR_FL 0x00020000 /* Top of directory hierarchies*/
+#define EXT2_RESERVED_FL 0x80000000 /* reserved for ext2 lib */
+
+#define EXT2_FL_USER_VISIBLE 0x0003DFFF /* User visible flags */
+#define EXT2_FL_USER_MODIFIABLE 0x000380FF /* 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 {
+ __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
+
+#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
+#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_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 0x0001 /* Do mount-time checks */
+#define EXT2_MOUNT_OLDALLOC 0x0002 /* Don't use the new Orlov allocator */
+#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_NOBH 0x0100 /* No buffer_heads */
+#define EXT2_MOUNT_NO_UID32 0x0200 /* Disable 32-bit UIDs */
+#define EXT2_MOUNT_XATTR_USER 0x4000 /* Extended user attributes */
+#define EXT2_MOUNT_POSIX_ACL 0x8000 /* POSIX Access Control Lists */
+
+#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,
+ EXT2_FT_REG_FILE,
+ EXT2_FT_DIR,
+ EXT2_FT_CHRDEV,
+ EXT2_FT_BLKDEV,
+ EXT2_FT_FIFO,
+ EXT2_FT_SOCK,
+ EXT2_FT_SYMLINK,
+ 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)
+
+#endif /* _LINUX_EXT2_FS_H */