/* 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 /* * 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_INODE 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 /* _LINUX_EXT2_FS_H */