1/* vi: set sw=4 ts=4: */ 2/* 3 * linux/include/linux/ext2_fs.h 4 * 5 * Copyright (C) 1992, 1993, 1994, 1995 6 * Remy Card (card@masi.ibp.fr) 7 * Laboratoire MASI - Institut Blaise Pascal 8 * Universite Pierre et Marie Curie (Paris VI) 9 * 10 * from 11 * 12 * linux/include/linux/minix_fs.h 13 * 14 * Copyright (C) 1991, 1992 Linus Torvalds 15 */ 16 17#ifndef _LINUX_EXT2_FS_H 18#define _LINUX_EXT2_FS_H 19 20#include "ext2_types.h" /* Changed from linux/types.h */ 21 22/* 23 * Special inode numbers 24 */ 25#define EXT2_BAD_INO 1 /* Bad blocks inode */ 26#define EXT2_ROOT_INO 2 /* Root inode */ 27#define EXT2_ACL_IDX_INO 3 /* ACL inode */ 28#define EXT2_ACL_DATA_INO 4 /* ACL inode */ 29#define EXT2_BOOT_LOADER_INO 5 /* Boot loader inode */ 30#define EXT2_UNDEL_DIR_INO 6 /* Undelete directory inode */ 31#define EXT2_RESIZE_INO 7 /* Reserved group descriptors inode */ 32#define EXT2_JOURNAL_INO 8 /* Journal inode */ 33 34/* First non-reserved inode for old ext2 filesystems */ 35#define EXT2_GOOD_OLD_FIRST_INO 11 36 37/* 38 * The second extended file system magic number 39 */ 40#define EXT2_SUPER_MAGIC 0xEF53 41 42/* Assume that user mode programs are passing in an ext2fs superblock, not 43 * a kernel struct super_block. This will allow us to call the feature-test 44 * macros from user land. */ 45#define EXT2_SB(sb) (sb) 46 47/* 48 * Maximal count of links to a file 49 */ 50#define EXT2_LINK_MAX 32000 51 52/* 53 * Macro-instructions used to manage several block sizes 54 */ 55#define EXT2_MIN_BLOCK_LOG_SIZE 10 /* 1024 */ 56#define EXT2_MAX_BLOCK_LOG_SIZE 16 /* 65536 */ 57#define EXT2_MIN_BLOCK_SIZE (1 << EXT2_MIN_BLOCK_LOG_SIZE) 58#define EXT2_MAX_BLOCK_SIZE (1 << EXT2_MAX_BLOCK_LOG_SIZE) 59#define EXT2_BLOCK_SIZE(s) (EXT2_MIN_BLOCK_SIZE << (s)->s_log_block_size) 60#define EXT2_BLOCK_SIZE_BITS(s) ((s)->s_log_block_size + 10) 61#define EXT2_INODE_SIZE(s) (((s)->s_rev_level == EXT2_GOOD_OLD_REV) ? \ 62 EXT2_GOOD_OLD_INODE_SIZE : (s)->s_inode_size) 63#define EXT2_FIRST_INO(s) (((s)->s_rev_level == EXT2_GOOD_OLD_REV) ? \ 64 EXT2_GOOD_OLD_FIRST_INO : (s)->s_first_ino) 65#define EXT2_ADDR_PER_BLOCK(s) (EXT2_BLOCK_SIZE(s) / sizeof(__u32)) 66 67/* 68 * Macro-instructions used to manage fragments 69 */ 70#define EXT2_MIN_FRAG_SIZE EXT2_MIN_BLOCK_SIZE 71#define EXT2_MAX_FRAG_SIZE EXT2_MAX_BLOCK_SIZE 72#define EXT2_MIN_FRAG_LOG_SIZE EXT2_MIN_BLOCK_LOG_SIZE 73# define EXT2_FRAG_SIZE(s) (EXT2_MIN_FRAG_SIZE << (s)->s_log_frag_size) 74# define EXT2_FRAGS_PER_BLOCK(s) (EXT2_BLOCK_SIZE(s) / EXT2_FRAG_SIZE(s)) 75 76/* 77 * ACL structures 78 */ 79struct ext2_acl_header /* Header of Access Control Lists */ 80{ 81 __u32 aclh_size; 82 __u32 aclh_file_count; 83 __u32 aclh_acle_count; 84 __u32 aclh_first_acle; 85}; 86 87struct ext2_acl_entry /* Access Control List Entry */ 88{ 89 __u32 acle_size; 90 __u16 acle_perms; /* Access permissions */ 91 __u16 acle_type; /* Type of entry */ 92 __u16 acle_tag; /* User or group identity */ 93 __u16 acle_pad1; 94 __u32 acle_next; /* Pointer on next entry for the */ 95 /* same inode or on next free entry */ 96}; 97 98/* 99 * Structure of a blocks group descriptor 100 */ 101struct ext2_group_desc 102{ 103 __u32 bg_block_bitmap; /* Blocks bitmap block */ 104 __u32 bg_inode_bitmap; /* Inodes bitmap block */ 105 __u32 bg_inode_table; /* Inodes table block */ 106 __u16 bg_free_blocks_count; /* Free blocks count */ 107 __u16 bg_free_inodes_count; /* Free inodes count */ 108 __u16 bg_used_dirs_count; /* Directories count */ 109 __u16 bg_pad; 110 __u32 bg_reserved[3]; 111}; 112 113/* 114 * Data structures used by the directory indexing feature 115 * 116 * Note: all of the multibyte integer fields are little endian. 117 */ 118 119/* 120 * Note: dx_root_info is laid out so that if it should somehow get 121 * overlaid by a dirent the two low bits of the hash version will be 122 * zero. Therefore, the hash version mod 4 should never be 0. 123 * Sincerely, the paranoia department. 124 */ 125struct ext2_dx_root_info { 126 __u32 reserved_zero; 127 __u8 hash_version; /* 0 now, 1 at release */ 128 __u8 info_length; /* 8 */ 129 __u8 indirect_levels; 130 __u8 unused_flags; 131}; 132 133#define EXT2_HASH_LEGACY 0 134#define EXT2_HASH_HALF_MD4 1 135#define EXT2_HASH_TEA 2 136 137#define EXT2_HASH_FLAG_INCOMPAT 0x1 138 139struct ext2_dx_entry { 140 __u32 hash; 141 __u32 block; 142}; 143 144struct ext2_dx_countlimit { 145 __u16 limit; 146 __u16 count; 147}; 148 149 150/* 151 * Macro-instructions used to manage group descriptors 152 */ 153#define EXT2_BLOCKS_PER_GROUP(s) (EXT2_SB(s)->s_blocks_per_group) 154#define EXT2_INODES_PER_GROUP(s) (EXT2_SB(s)->s_inodes_per_group) 155#define EXT2_INODES_PER_BLOCK(s) (EXT2_BLOCK_SIZE(s)/EXT2_INODE_SIZE(s)) 156/* limits imposed by 16-bit value gd_free_{blocks,inode}_count */ 157#define EXT2_MAX_BLOCKS_PER_GROUP(s) ((1 << 16) - 8) 158#define EXT2_MAX_INODES_PER_GROUP(s) ((1 << 16) - EXT2_INODES_PER_BLOCK(s)) 159#define EXT2_DESC_PER_BLOCK(s) (EXT2_BLOCK_SIZE(s) / sizeof (struct ext2_group_desc)) 160 161/* 162 * Constants relative to the data blocks 163 */ 164#define EXT2_NDIR_BLOCKS 12 165#define EXT2_IND_BLOCK EXT2_NDIR_BLOCKS 166#define EXT2_DIND_BLOCK (EXT2_IND_BLOCK + 1) 167#define EXT2_TIND_BLOCK (EXT2_DIND_BLOCK + 1) 168#define EXT2_N_BLOCKS (EXT2_TIND_BLOCK + 1) 169 170/* 171 * Inode flags 172 */ 173#define EXT2_SECRM_FL 0x00000001 /* Secure deletion */ 174#define EXT2_UNRM_FL 0x00000002 /* Undelete */ 175#define EXT2_COMPR_FL 0x00000004 /* Compress file */ 176#define EXT2_SYNC_FL 0x00000008 /* Synchronous updates */ 177#define EXT2_IMMUTABLE_FL 0x00000010 /* Immutable file */ 178#define EXT2_APPEND_FL 0x00000020 /* writes to file may only append */ 179#define EXT2_NODUMP_FL 0x00000040 /* do not dump file */ 180#define EXT2_NOATIME_FL 0x00000080 /* do not update atime */ 181/* Reserved for compression usage... */ 182#define EXT2_DIRTY_FL 0x00000100 183#define EXT2_COMPRBLK_FL 0x00000200 /* One or more compressed clusters */ 184#define EXT2_NOCOMPR_FL 0x00000400 /* Access raw compressed data */ 185#define EXT2_ECOMPR_FL 0x00000800 /* Compression error */ 186/* End compression flags --- maybe not all used */ 187#define EXT2_BTREE_FL 0x00001000 /* btree format dir */ 188#define EXT2_INDEX_FL 0x00001000 /* hash-indexed directory */ 189#define EXT2_IMAGIC_FL 0x00002000 190#define EXT3_JOURNAL_DATA_FL 0x00004000 /* file data should be journaled */ 191#define EXT2_NOTAIL_FL 0x00008000 /* file tail should not be merged */ 192#define EXT2_DIRSYNC_FL 0x00010000 /* Synchronous directory modifications */ 193#define EXT2_TOPDIR_FL 0x00020000 /* Top of directory hierarchies*/ 194#define EXT3_EXTENTS_FL 0x00080000 /* Inode uses extents */ 195#define EXT2_RESERVED_FL 0x80000000 /* reserved for ext2 lib */ 196 197#define EXT2_FL_USER_VISIBLE 0x0003DFFF /* User visible flags */ 198#define EXT2_FL_USER_MODIFIABLE 0x000080FF /* User modifiable flags */ 199 200/* 201 * ioctl commands 202 */ 203#define EXT2_IOC_GETFLAGS _IOR('f', 1, long) 204#define EXT2_IOC_SETFLAGS _IOW('f', 2, long) 205#define EXT2_IOC_GETVERSION _IOR('v', 1, long) 206#define EXT2_IOC_SETVERSION _IOW('v', 2, long) 207 208/* 209 * Structure of an inode on the disk 210 */ 211struct ext2_inode { 212 __u16 i_mode; /* File mode */ 213 __u16 i_uid; /* Low 16 bits of Owner Uid */ 214 __u32 i_size; /* Size in bytes */ 215 __u32 i_atime; /* Access time */ 216 __u32 i_ctime; /* Creation time */ 217 __u32 i_mtime; /* Modification time */ 218 __u32 i_dtime; /* Deletion Time */ 219 __u16 i_gid; /* Low 16 bits of Group Id */ 220 __u16 i_links_count; /* Links count */ 221 __u32 i_blocks; /* Blocks count */ 222 __u32 i_flags; /* File flags */ 223 union { 224 struct { 225 __u32 l_i_reserved1; 226 } linux1; 227 struct { 228 __u32 h_i_translator; 229 } hurd1; 230 struct { 231 __u32 m_i_reserved1; 232 } masix1; 233 } osd1; /* OS dependent 1 */ 234 __u32 i_block[EXT2_N_BLOCKS];/* Pointers to blocks */ 235 __u32 i_generation; /* File version (for NFS) */ 236 __u32 i_file_acl; /* File ACL */ 237 __u32 i_dir_acl; /* Directory ACL */ 238 __u32 i_faddr; /* Fragment address */ 239 union { 240 struct { 241 __u8 l_i_frag; /* Fragment number */ 242 __u8 l_i_fsize; /* Fragment size */ 243 __u16 i_pad1; 244 __u16 l_i_uid_high; /* these 2 fields */ 245 __u16 l_i_gid_high; /* were reserved2[0] */ 246 __u32 l_i_reserved2; 247 } linux2; 248 struct { 249 __u8 h_i_frag; /* Fragment number */ 250 __u8 h_i_fsize; /* Fragment size */ 251 __u16 h_i_mode_high; 252 __u16 h_i_uid_high; 253 __u16 h_i_gid_high; 254 __u32 h_i_author; 255 } hurd2; 256 struct { 257 __u8 m_i_frag; /* Fragment number */ 258 __u8 m_i_fsize; /* Fragment size */ 259 __u16 m_pad1; 260 __u32 m_i_reserved2[2]; 261 } masix2; 262 } osd2; /* OS dependent 2 */ 263}; 264 265/* 266 * Permanent part of an large inode on the disk 267 */ 268struct ext2_inode_large { 269 __u16 i_mode; /* File mode */ 270 __u16 i_uid; /* Low 16 bits of Owner Uid */ 271 __u32 i_size; /* Size in bytes */ 272 __u32 i_atime; /* Access time */ 273 __u32 i_ctime; /* Creation time */ 274 __u32 i_mtime; /* Modification time */ 275 __u32 i_dtime; /* Deletion Time */ 276 __u16 i_gid; /* Low 16 bits of Group Id */ 277 __u16 i_links_count; /* Links count */ 278 __u32 i_blocks; /* Blocks count */ 279 __u32 i_flags; /* File flags */ 280 union { 281 struct { 282 __u32 l_i_reserved1; 283 } linux1; 284 struct { 285 __u32 h_i_translator; 286 } hurd1; 287 struct { 288 __u32 m_i_reserved1; 289 } masix1; 290 } osd1; /* OS dependent 1 */ 291 __u32 i_block[EXT2_N_BLOCKS];/* Pointers to blocks */ 292 __u32 i_generation; /* File version (for NFS) */ 293 __u32 i_file_acl; /* File ACL */ 294 __u32 i_dir_acl; /* Directory ACL */ 295 __u32 i_faddr; /* Fragment address */ 296 union { 297 struct { 298 __u8 l_i_frag; /* Fragment number */ 299 __u8 l_i_fsize; /* Fragment size */ 300 __u16 i_pad1; 301 __u16 l_i_uid_high; /* these 2 fields */ 302 __u16 l_i_gid_high; /* were reserved2[0] */ 303 __u32 l_i_reserved2; 304 } linux2; 305 struct { 306 __u8 h_i_frag; /* Fragment number */ 307 __u8 h_i_fsize; /* Fragment size */ 308 __u16 h_i_mode_high; 309 __u16 h_i_uid_high; 310 __u16 h_i_gid_high; 311 __u32 h_i_author; 312 } hurd2; 313 struct { 314 __u8 m_i_frag; /* Fragment number */ 315 __u8 m_i_fsize; /* Fragment size */ 316 __u16 m_pad1; 317 __u32 m_i_reserved2[2]; 318 } masix2; 319 } osd2; /* OS dependent 2 */ 320 __u16 i_extra_isize; 321 __u16 i_pad1; 322}; 323 324#define i_size_high i_dir_acl 325 326/* 327 * File system states 328 */ 329#define EXT2_VALID_FS 0x0001 /* Unmounted cleanly */ 330#define EXT2_ERROR_FS 0x0002 /* Errors detected */ 331 332/* 333 * Mount flags 334 */ 335#define EXT2_MOUNT_CHECK 0x0001 /* Do mount-time checks */ 336#define EXT2_MOUNT_GRPID 0x0004 /* Create files with directory's group */ 337#define EXT2_MOUNT_DEBUG 0x0008 /* Some debugging messages */ 338#define EXT2_MOUNT_ERRORS_CONT 0x0010 /* Continue on errors */ 339#define EXT2_MOUNT_ERRORS_RO 0x0020 /* Remount fs ro on errors */ 340#define EXT2_MOUNT_ERRORS_PANIC 0x0040 /* Panic on errors */ 341#define EXT2_MOUNT_MINIX_DF 0x0080 /* Mimics the Minix statfs */ 342#define EXT2_MOUNT_NO_UID32 0x0200 /* Disable 32-bit UIDs */ 343 344#define clear_opt(o, opt) o &= ~EXT2_MOUNT_##opt 345#define set_opt(o, opt) o |= EXT2_MOUNT_##opt 346#define test_opt(sb, opt) (EXT2_SB(sb)->s_mount_opt & \ 347 EXT2_MOUNT_##opt) 348/* 349 * Maximal mount counts between two filesystem checks 350 */ 351#define EXT2_DFL_MAX_MNT_COUNT 20 /* Allow 20 mounts */ 352#define EXT2_DFL_CHECKINTERVAL 0 /* Don't use interval check */ 353 354/* 355 * Behaviour when detecting errors 356 */ 357#define EXT2_ERRORS_CONTINUE 1 /* Continue execution */ 358#define EXT2_ERRORS_RO 2 /* Remount fs read-only */ 359#define EXT2_ERRORS_PANIC 3 /* Panic */ 360#define EXT2_ERRORS_DEFAULT EXT2_ERRORS_CONTINUE 361 362/* 363 * Structure of the super block 364 */ 365struct ext2_super_block { 366 __u32 s_inodes_count; /* Inodes count */ 367 __u32 s_blocks_count; /* Blocks count */ 368 __u32 s_r_blocks_count; /* Reserved blocks count */ 369 __u32 s_free_blocks_count; /* Free blocks count */ 370 __u32 s_free_inodes_count; /* Free inodes count */ 371 __u32 s_first_data_block; /* First Data Block */ 372 __u32 s_log_block_size; /* Block size */ 373 __s32 s_log_frag_size; /* Fragment size */ 374 __u32 s_blocks_per_group; /* # Blocks per group */ 375 __u32 s_frags_per_group; /* # Fragments per group */ 376 __u32 s_inodes_per_group; /* # Inodes per group */ 377 __u32 s_mtime; /* Mount time */ 378 __u32 s_wtime; /* Write time */ 379 __u16 s_mnt_count; /* Mount count */ 380 __s16 s_max_mnt_count; /* Maximal mount count */ 381 __u16 s_magic; /* Magic signature */ 382 __u16 s_state; /* File system state */ 383 __u16 s_errors; /* Behaviour when detecting errors */ 384 __u16 s_minor_rev_level; /* minor revision level */ 385 __u32 s_lastcheck; /* time of last check */ 386 __u32 s_checkinterval; /* max. time between checks */ 387 __u32 s_creator_os; /* OS */ 388 __u32 s_rev_level; /* Revision level */ 389 __u16 s_def_resuid; /* Default uid for reserved blocks */ 390 __u16 s_def_resgid; /* Default gid for reserved blocks */ 391 /* 392 * These fields are for EXT2_DYNAMIC_REV superblocks only. 393 * 394 * Note: the difference between the compatible feature set and 395 * the incompatible feature set is that if there is a bit set 396 * in the incompatible feature set that the kernel doesn't 397 * know about, it should refuse to mount the filesystem. 398 * 399 * e2fsck's requirements are more strict; if it doesn't know 400 * about a feature in either the compatible or incompatible 401 * feature set, it must abort and not try to meddle with 402 * things it doesn't understand... 403 */ 404 __u32 s_first_ino; /* First non-reserved inode */ 405 __u16 s_inode_size; /* size of inode structure */ 406 __u16 s_block_group_nr; /* block group # of this superblock */ 407 __u32 s_feature_compat; /* compatible feature set */ 408 __u32 s_feature_incompat; /* incompatible feature set */ 409 __u32 s_feature_ro_compat; /* readonly-compatible feature set */ 410 __u8 s_uuid[16]; /* 128-bit uuid for volume */ 411 char s_volume_name[16]; /* volume name */ 412 char s_last_mounted[64]; /* directory where last mounted */ 413 __u32 s_algorithm_usage_bitmap; /* For compression */ 414 /* 415 * Performance hints. Directory preallocation should only 416 * happen if the EXT2_FEATURE_COMPAT_DIR_PREALLOC flag is on. 417 */ 418 __u8 s_prealloc_blocks; /* Nr of blocks to try to preallocate*/ 419 __u8 s_prealloc_dir_blocks; /* Nr to preallocate for dirs */ 420 __u16 s_reserved_gdt_blocks; /* Per group table for online growth */ 421 /* 422 * Journaling support valid if EXT2_FEATURE_COMPAT_HAS_JOURNAL set. 423 */ 424 __u8 s_journal_uuid[16]; /* uuid of journal superblock */ 425 __u32 s_journal_inum; /* inode number of journal file */ 426 __u32 s_journal_dev; /* device number of journal file */ 427 __u32 s_last_orphan; /* start of list of inodes to delete */ 428 __u32 s_hash_seed[4]; /* HTREE hash seed */ 429 __u8 s_def_hash_version; /* Default hash version to use */ 430 __u8 s_jnl_backup_type; /* Default type of journal backup */ 431 __u16 s_reserved_word_pad; 432 __u32 s_default_mount_opts; 433 __u32 s_first_meta_bg; /* First metablock group */ 434 __u32 s_mkfs_time; /* When the filesystem was created */ 435 __u32 s_jnl_blocks[17]; /* Backup of the journal inode */ 436 __u32 s_reserved[172]; /* Padding to the end of the block */ 437}; 438 439/* 440 * Codes for operating systems 441 */ 442#define EXT2_OS_LINUX 0 443#define EXT2_OS_HURD 1 444#define EXT2_OS_MASIX 2 445#define EXT2_OS_FREEBSD 3 446#define EXT2_OS_LITES 4 447 448/* 449 * Revision levels 450 */ 451#define EXT2_GOOD_OLD_REV 0 /* The good old (original) format */ 452#define EXT2_DYNAMIC_REV 1 /* V2 format w/ dynamic inode sizes */ 453 454#define EXT2_CURRENT_REV EXT2_GOOD_OLD_REV 455#define EXT2_MAX_SUPP_REV EXT2_DYNAMIC_REV 456 457#define EXT2_GOOD_OLD_INODE_SIZE 128 458 459/* 460 * Journal inode backup types 461 */ 462#define EXT3_JNL_BACKUP_BLOCKS 1 463 464/* 465 * Feature set definitions 466 */ 467 468#define EXT2_HAS_COMPAT_FEATURE(sb,mask) \ 469 ( EXT2_SB(sb)->s_feature_compat & (mask) ) 470#define EXT2_HAS_RO_COMPAT_FEATURE(sb,mask) \ 471 ( EXT2_SB(sb)->s_feature_ro_compat & (mask) ) 472#define EXT2_HAS_INCOMPAT_FEATURE(sb,mask) \ 473 ( EXT2_SB(sb)->s_feature_incompat & (mask) ) 474 475#define EXT2_FEATURE_COMPAT_DIR_PREALLOC 0x0001 476#define EXT2_FEATURE_COMPAT_IMAGIC_INODES 0x0002 477#define EXT3_FEATURE_COMPAT_HAS_JOURNAL 0x0004 478#define EXT2_FEATURE_COMPAT_EXT_ATTR 0x0008 479#define EXT2_FEATURE_COMPAT_RESIZE_INODE 0x0010 480#define EXT2_FEATURE_COMPAT_DIR_INDEX 0x0020 481 482#define EXT2_FEATURE_RO_COMPAT_SPARSE_SUPER 0x0001 483#define EXT2_FEATURE_RO_COMPAT_LARGE_FILE 0x0002 484/* #define EXT2_FEATURE_RO_COMPAT_BTREE_DIR 0x0004 not used */ 485 486#define EXT2_FEATURE_INCOMPAT_COMPRESSION 0x0001 487#define EXT2_FEATURE_INCOMPAT_FILETYPE 0x0002 488#define EXT3_FEATURE_INCOMPAT_RECOVER 0x0004 /* Needs recovery */ 489#define EXT3_FEATURE_INCOMPAT_JOURNAL_DEV 0x0008 /* Journal device */ 490#define EXT2_FEATURE_INCOMPAT_META_BG 0x0010 491#define EXT3_FEATURE_INCOMPAT_EXTENTS 0x0040 492 493 494#define EXT2_FEATURE_COMPAT_SUPP 0 495#define EXT2_FEATURE_INCOMPAT_SUPP (EXT2_FEATURE_INCOMPAT_FILETYPE) 496#define EXT2_FEATURE_RO_COMPAT_SUPP (EXT2_FEATURE_RO_COMPAT_SPARSE_SUPER| \ 497 EXT2_FEATURE_RO_COMPAT_LARGE_FILE| \ 498 EXT2_FEATURE_RO_COMPAT_BTREE_DIR) 499 500/* 501 * Default values for user and/or group using reserved blocks 502 */ 503#define EXT2_DEF_RESUID 0 504#define EXT2_DEF_RESGID 0 505 506/* 507 * Default mount options 508 */ 509#define EXT2_DEFM_DEBUG 0x0001 510#define EXT2_DEFM_BSDGROUPS 0x0002 511#define EXT2_DEFM_XATTR_USER 0x0004 512#define EXT2_DEFM_ACL 0x0008 513#define EXT2_DEFM_UID16 0x0010 514#define EXT3_DEFM_JMODE 0x0060 515#define EXT3_DEFM_JMODE_DATA 0x0020 516#define EXT3_DEFM_JMODE_ORDERED 0x0040 517#define EXT3_DEFM_JMODE_WBACK 0x0060 518 519/* 520 * Structure of a directory entry 521 */ 522#define EXT2_NAME_LEN 255 523 524struct ext2_dir_entry { 525 __u32 inode; /* Inode number */ 526 __u16 rec_len; /* Directory entry length */ 527 __u16 name_len; /* Name length */ 528 char name[EXT2_NAME_LEN]; /* File name */ 529}; 530 531/* 532 * The new version of the directory entry. Since EXT2 structures are 533 * stored in intel byte order, and the name_len field could never be 534 * bigger than 255 chars, it's safe to reclaim the extra byte for the 535 * file_type field. 536 */ 537struct ext2_dir_entry_2 { 538 __u32 inode; /* Inode number */ 539 __u16 rec_len; /* Directory entry length */ 540 __u8 name_len; /* Name length */ 541 __u8 file_type; 542 char name[EXT2_NAME_LEN]; /* File name */ 543}; 544 545/* 546 * Ext2 directory file types. Only the low 3 bits are used. The 547 * other bits are reserved for now. 548 */ 549#define EXT2_FT_UNKNOWN 0 550#define EXT2_FT_REG_FILE 1 551#define EXT2_FT_DIR 2 552#define EXT2_FT_CHRDEV 3 553#define EXT2_FT_BLKDEV 4 554#define EXT2_FT_FIFO 5 555#define EXT2_FT_SOCK 6 556#define EXT2_FT_SYMLINK 7 557 558#define EXT2_FT_MAX 8 559 560/* 561 * EXT2_DIR_PAD defines the directory entries boundaries 562 * 563 * NOTE: It must be a multiple of 4 564 */ 565#define EXT2_DIR_PAD 4 566#define EXT2_DIR_ROUND (EXT2_DIR_PAD - 1) 567#define EXT2_DIR_REC_LEN(name_len) (((name_len) + 8 + EXT2_DIR_ROUND) & \ 568 ~EXT2_DIR_ROUND) 569 570#endif /* _LINUX_EXT2_FS_H */ 571