ext2_fs.h revision 5ea565fd37821b2708c2b7f1e49fe6fc94587794
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 <ext2fs/ext2_types.h> /* Changed from linux/types.h */ 20 21/* 22 * The second extended filesystem constants/structures 23 */ 24 25/* 26 * Define EXT2FS_DEBUG to produce debug messages 27 */ 28#undef EXT2FS_DEBUG 29 30/* 31 * Define EXT2_PREALLOCATE to preallocate data blocks for expanding files 32 */ 33#define EXT2_PREALLOCATE 34#define EXT2_DEFAULT_PREALLOC_BLOCKS 8 35 36/* 37 * The second extended file system version 38 */ 39#define EXT2FS_DATE "95/08/09" 40#define EXT2FS_VERSION "0.5b" 41 42/* 43 * Special inode numbers 44 */ 45#define EXT2_BAD_INO 1 /* Bad blocks inode */ 46#define EXT2_ROOT_INO 2 /* Root inode */ 47#define EXT2_ACL_IDX_INO 3 /* ACL inode */ 48#define EXT2_ACL_DATA_INO 4 /* ACL inode */ 49#define EXT2_BOOT_LOADER_INO 5 /* Boot loader inode */ 50#define EXT2_UNDEL_DIR_INO 6 /* Undelete directory inode */ 51#define EXT2_RESIZE_INO 7 /* Reserved group descriptors inode */ 52#define EXT2_JOURNAL_INO 8 /* Journal inode */ 53 54/* First non-reserved inode for old ext2 filesystems */ 55#define EXT2_GOOD_OLD_FIRST_INO 11 56 57/* 58 * The second extended file system magic number 59 */ 60#define EXT2_SUPER_MAGIC 0xEF53 61 62#ifdef __KERNEL__ 63#define EXT2_SB(sb) (&((sb)->u.ext2_sb)) 64#else 65/* Assume that user mode programs are passing in an ext2fs superblock, not 66 * a kernel struct super_block. This will allow us to call the feature-test 67 * macros from user land. */ 68#define EXT2_SB(sb) (sb) 69#endif 70 71/* 72 * Maximal count of links to a file 73 */ 74#define EXT2_LINK_MAX 65000 75 76/* 77 * Macro-instructions used to manage several block sizes 78 */ 79#define EXT2_MIN_BLOCK_LOG_SIZE 10 /* 1024 */ 80#define EXT2_MAX_BLOCK_LOG_SIZE 16 /* 65536 */ 81#define EXT2_MIN_BLOCK_SIZE (1 << EXT2_MIN_BLOCK_LOG_SIZE) 82#define EXT2_MAX_BLOCK_SIZE (1 << EXT2_MAX_BLOCK_LOG_SIZE) 83#ifdef __KERNEL__ 84#define EXT2_BLOCK_SIZE(s) ((s)->s_blocksize) 85#define EXT2_BLOCK_SIZE_BITS(s) ((s)->s_blocksize_bits) 86#define EXT2_ADDR_PER_BLOCK_BITS(s) (EXT2_SB(s)->addr_per_block_bits) 87#define EXT2_INODE_SIZE(s) (EXT2_SB(s)->s_inode_size) 88#define EXT2_FIRST_INO(s) (EXT2_SB(s)->s_first_ino) 89#else 90#define EXT2_BLOCK_SIZE(s) (EXT2_MIN_BLOCK_SIZE << (s)->s_log_block_size) 91#define EXT2_BLOCK_SIZE_BITS(s) ((s)->s_log_block_size + 10) 92#define EXT2_INODE_SIZE(s) (((s)->s_rev_level == EXT2_GOOD_OLD_REV) ? \ 93 EXT2_GOOD_OLD_INODE_SIZE : (s)->s_inode_size) 94#define EXT2_FIRST_INO(s) (((s)->s_rev_level == EXT2_GOOD_OLD_REV) ? \ 95 EXT2_GOOD_OLD_FIRST_INO : (s)->s_first_ino) 96#endif 97#define EXT2_ADDR_PER_BLOCK(s) (EXT2_BLOCK_SIZE(s) / sizeof(__u32)) 98 99/* 100 * Macro-instructions used to manage fragments 101 */ 102#define EXT2_MIN_FRAG_SIZE EXT2_MIN_BLOCK_SIZE 103#define EXT2_MAX_FRAG_SIZE EXT2_MAX_BLOCK_SIZE 104#define EXT2_MIN_FRAG_LOG_SIZE EXT2_MIN_BLOCK_LOG_SIZE 105#ifdef __KERNEL__ 106# define EXT2_FRAG_SIZE(s) (EXT2_SB(s)->s_frag_size) 107# define EXT2_FRAGS_PER_BLOCK(s) (EXT2_SB(s)->s_frags_per_block) 108#else 109# define EXT2_FRAG_SIZE(s) (EXT2_MIN_FRAG_SIZE << (s)->s_log_frag_size) 110# define EXT2_FRAGS_PER_BLOCK(s) (EXT2_BLOCK_SIZE(s) / EXT2_FRAG_SIZE(s)) 111#endif 112 113/* 114 * ACL structures 115 */ 116struct ext2_acl_header /* Header of Access Control Lists */ 117{ 118 __u32 aclh_size; 119 __u32 aclh_file_count; 120 __u32 aclh_acle_count; 121 __u32 aclh_first_acle; 122}; 123 124struct ext2_acl_entry /* Access Control List Entry */ 125{ 126 __u32 acle_size; 127 __u16 acle_perms; /* Access permissions */ 128 __u16 acle_type; /* Type of entry */ 129 __u16 acle_tag; /* User or group identity */ 130 __u16 acle_pad1; 131 __u32 acle_next; /* Pointer on next entry for the */ 132 /* same inode or on next free entry */ 133}; 134 135/* 136 * Structure of a blocks group descriptor 137 */ 138struct ext2_group_desc 139{ 140 __u32 bg_block_bitmap; /* Blocks bitmap block */ 141 __u32 bg_inode_bitmap; /* Inodes bitmap block */ 142 __u32 bg_inode_table; /* Inodes table block */ 143 __u16 bg_free_blocks_count; /* Free blocks count */ 144 __u16 bg_free_inodes_count; /* Free inodes count */ 145 __u16 bg_used_dirs_count; /* Directories count */ 146 __u16 bg_flags; 147 __u32 bg_reserved[2]; 148 __u16 bg_itable_unused; /* Unused inodes count */ 149 __u16 bg_checksum; /* crc16(s_uuid+grouo_num+group_desc)*/ 150}; 151 152struct ext4_group_desc 153{ 154 __u32 bg_block_bitmap; /* Blocks bitmap block */ 155 __u32 bg_inode_bitmap; /* Inodes bitmap block */ 156 __u32 bg_inode_table; /* Inodes table block */ 157 __u16 bg_free_blocks_count; /* Free blocks count */ 158 __u16 bg_free_inodes_count; /* Free inodes count */ 159 __u16 bg_used_dirs_count; /* Directories count */ 160 __u16 bg_flags; 161 __u32 bg_reserved[2]; 162 __u16 bg_itable_unused; /* Unused inodes count */ 163 __u16 bg_checksum; /* crc16(s_uuid+grouo_num+group_desc)*/ 164 __u32 bg_block_bitmap_hi; /* Blocks bitmap block MSB */ 165 __u32 bg_inode_bitmap_hi; /* Inodes bitmap block MSB */ 166 __u32 bg_inode_table_hi; /* Inodes table block MSB */ 167 __u16 bg_free_blocks_count_hi;/* Free blocks count MSB */ 168 __u16 bg_free_inodes_count_hi;/* Free inodes count MSB */ 169 __u16 bg_used_dirs_count_hi; /* Directories count MSB */ 170 __u16 bg_pad; 171 __u32 bg_reserved2[3]; 172}; 173 174#define EXT2_BG_INODE_UNINIT 0x0001 /* Inode table/bitmap not initialized */ 175#define EXT2_BG_BLOCK_UNINIT 0x0002 /* Block bitmap not initialized */ 176 177/* 178 * Data structures used by the directory indexing feature 179 * 180 * Note: all of the multibyte integer fields are little endian. 181 */ 182 183/* 184 * Note: dx_root_info is laid out so that if it should somehow get 185 * overlaid by a dirent the two low bits of the hash version will be 186 * zero. Therefore, the hash version mod 4 should never be 0. 187 * Sincerely, the paranoia department. 188 */ 189struct ext2_dx_root_info { 190 __u32 reserved_zero; 191 __u8 hash_version; /* 0 now, 1 at release */ 192 __u8 info_length; /* 8 */ 193 __u8 indirect_levels; 194 __u8 unused_flags; 195}; 196 197#define EXT2_HASH_LEGACY 0 198#define EXT2_HASH_HALF_MD4 1 199#define EXT2_HASH_TEA 2 200#define EXT2_HASH_LEGACY_UNSIGNED 3 /* reserved for userspace lib */ 201#define EXT2_HASH_HALF_MD4_UNSIGNED 4 /* reserved for userspace lib */ 202#define EXT2_HASH_TEA_UNSIGNED 5 /* reserved for userspace lib */ 203 204#define EXT2_HASH_FLAG_INCOMPAT 0x1 205 206struct ext2_dx_entry { 207 __u32 hash; 208 __u32 block; 209}; 210 211struct ext2_dx_countlimit { 212 __u16 limit; 213 __u16 count; 214}; 215 216 217/* 218 * Macro-instructions used to manage group descriptors 219 */ 220#define EXT2_MIN_DESC_SIZE 32 221#define EXT2_MIN_DESC_SIZE_64BIT 64 222#define EXT2_MAX_DESC_SIZE EXT2_MIN_BLOCK_SIZE 223#define EXT2_DESC_SIZE(s) \ 224 ((EXT2_SB(s)->s_feature_incompat & EXT4_FEATURE_INCOMPAT_64BIT) ? \ 225 (s)->s_desc_size : EXT2_MIN_DESC_SIZE) 226 227#define EXT2_BLOCKS_PER_GROUP(s) (EXT2_SB(s)->s_blocks_per_group) 228#define EXT2_INODES_PER_GROUP(s) (EXT2_SB(s)->s_inodes_per_group) 229#define EXT2_INODES_PER_BLOCK(s) (EXT2_BLOCK_SIZE(s)/EXT2_INODE_SIZE(s)) 230/* limits imposed by 16-bit value gd_free_{blocks,inode}_count */ 231#define EXT2_MAX_BLOCKS_PER_GROUP(s) ((1 << 16) - 8) 232#define EXT2_MAX_INODES_PER_GROUP(s) ((1 << 16) - EXT2_INODES_PER_BLOCK(s)) 233#ifdef __KERNEL__ 234#define EXT2_DESC_PER_BLOCK(s) (EXT2_SB(s)->s_desc_per_block) 235#define EXT2_DESC_PER_BLOCK_BITS(s) (EXT2_SB(s)->s_desc_per_block_bits) 236#else 237#define EXT2_DESC_PER_BLOCK(s) (EXT2_BLOCK_SIZE(s) / EXT2_DESC_SIZE(s)) 238#endif 239 240/* 241 * Constants relative to the data blocks 242 */ 243#define EXT2_NDIR_BLOCKS 12 244#define EXT2_IND_BLOCK EXT2_NDIR_BLOCKS 245#define EXT2_DIND_BLOCK (EXT2_IND_BLOCK + 1) 246#define EXT2_TIND_BLOCK (EXT2_DIND_BLOCK + 1) 247#define EXT2_N_BLOCKS (EXT2_TIND_BLOCK + 1) 248 249/* 250 * Inode flags 251 */ 252#define EXT2_SECRM_FL 0x00000001 /* Secure deletion */ 253#define EXT2_UNRM_FL 0x00000002 /* Undelete */ 254#define EXT2_COMPR_FL 0x00000004 /* Compress file */ 255#define EXT2_SYNC_FL 0x00000008 /* Synchronous updates */ 256#define EXT2_IMMUTABLE_FL 0x00000010 /* Immutable file */ 257#define EXT2_APPEND_FL 0x00000020 /* writes to file may only append */ 258#define EXT2_NODUMP_FL 0x00000040 /* do not dump file */ 259#define EXT2_NOATIME_FL 0x00000080 /* do not update atime */ 260/* Reserved for compression usage... */ 261#define EXT2_DIRTY_FL 0x00000100 262#define EXT2_COMPRBLK_FL 0x00000200 /* One or more compressed clusters */ 263#define EXT2_NOCOMPR_FL 0x00000400 /* Access raw compressed data */ 264#define EXT2_ECOMPR_FL 0x00000800 /* Compression error */ 265/* End compression flags --- maybe not all used */ 266#define EXT2_BTREE_FL 0x00001000 /* btree format dir */ 267#define EXT2_INDEX_FL 0x00001000 /* hash-indexed directory */ 268#define EXT2_IMAGIC_FL 0x00002000 269#define EXT3_JOURNAL_DATA_FL 0x00004000 /* file data should be journaled */ 270#define EXT2_NOTAIL_FL 0x00008000 /* file tail should not be merged */ 271#define EXT2_DIRSYNC_FL 0x00010000 /* Synchronous directory modifications */ 272#define EXT2_TOPDIR_FL 0x00020000 /* Top of directory hierarchies*/ 273#define EXT4_EXTENTS_FL 0x00080000 /* Inode uses extents */ 274#define EXT2_RESERVED_FL 0x80000000 /* reserved for ext2 lib */ 275 276#define EXT2_FL_USER_VISIBLE 0x000BDFFF /* User visible flags */ 277#define EXT2_FL_USER_MODIFIABLE 0x000080FF /* User modifiable flags */ 278 279/* 280 * ioctl commands 281 */ 282 283/* Used for online resize */ 284struct ext2_new_group_input { 285 __u32 group; /* Group number for this data */ 286 __u32 block_bitmap; /* Absolute block number of block bitmap */ 287 __u32 inode_bitmap; /* Absolute block number of inode bitmap */ 288 __u32 inode_table; /* Absolute block number of inode table start */ 289 __u32 blocks_count; /* Total number of blocks in this group */ 290 __u16 reserved_blocks; /* Number of reserved blocks in this group */ 291 __u16 unused; /* Number of reserved GDT blocks in group */ 292}; 293 294#define EXT2_IOC_GETFLAGS _IOR('f', 1, long) 295#define EXT2_IOC_SETFLAGS _IOW('f', 2, long) 296#define EXT2_IOC_GETVERSION _IOR('v', 1, long) 297#define EXT2_IOC_SETVERSION _IOW('v', 2, long) 298#define EXT2_IOC_GETVERSION_NEW _IOR('f', 3, long) 299#define EXT2_IOC_SETVERSION_NEW _IOW('f', 4, long) 300#define EXT2_IOC_GROUP_EXTEND _IOW('f', 7, unsigned long) 301#define EXT2_IOC_GROUP_ADD _IOW('f', 8,struct ext2_new_group_input) 302 303/* 304 * Structure of an inode on the disk 305 */ 306struct ext2_inode { 307 __u16 i_mode; /* File mode */ 308 __u16 i_uid; /* Low 16 bits of Owner Uid */ 309 __u32 i_size; /* Size in bytes */ 310 __u32 i_atime; /* Access time */ 311 __u32 i_ctime; /* Inode change time */ 312 __u32 i_mtime; /* Modification time */ 313 __u32 i_dtime; /* Deletion Time */ 314 __u16 i_gid; /* Low 16 bits of Group Id */ 315 __u16 i_links_count; /* Links count */ 316 __u32 i_blocks; /* Blocks count */ 317 __u32 i_flags; /* File flags */ 318 union { 319 struct { 320 __u32 l_i_version; /* was l_i_reserved1 */ 321 } linux1; 322 struct { 323 __u32 h_i_translator; 324 } hurd1; 325 } osd1; /* OS dependent 1 */ 326 __u32 i_block[EXT2_N_BLOCKS];/* Pointers to blocks */ 327 __u32 i_generation; /* File version (for NFS) */ 328 __u32 i_file_acl; /* File ACL */ 329 __u32 i_dir_acl; /* Directory ACL */ 330 __u32 i_faddr; /* Fragment address */ 331 union { 332 struct { 333 __u16 l_i_blocks_hi; 334 __u16 i_pad1; 335 __u16 l_i_uid_high; /* these 2 fields */ 336 __u16 l_i_gid_high; /* were reserved2[0] */ 337 __u32 l_i_reserved2; 338 } linux2; 339 struct { 340 __u8 h_i_frag; /* Fragment number */ 341 __u8 h_i_fsize; /* Fragment size */ 342 __u16 h_i_mode_high; 343 __u16 h_i_uid_high; 344 __u16 h_i_gid_high; 345 __u32 h_i_author; 346 } hurd2; 347 } osd2; /* OS dependent 2 */ 348}; 349 350/* 351 * Permanent part of an large inode on the disk 352 */ 353struct ext2_inode_large { 354 __u16 i_mode; /* File mode */ 355 __u16 i_uid; /* Low 16 bits of Owner Uid */ 356 __u32 i_size; /* Size in bytes */ 357 __u32 i_atime; /* Access time */ 358 __u32 i_ctime; /* Inode Change time */ 359 __u32 i_mtime; /* Modification time */ 360 __u32 i_dtime; /* Deletion Time */ 361 __u16 i_gid; /* Low 16 bits of Group Id */ 362 __u16 i_links_count; /* Links count */ 363 __u32 i_blocks; /* Blocks count */ 364 __u32 i_flags; /* File flags */ 365 union { 366 struct { 367 __u32 l_i_version; /* was l_i_reserved1 */ 368 } linux1; 369 struct { 370 __u32 h_i_translator; 371 } hurd1; 372 } osd1; /* OS dependent 1 */ 373 __u32 i_block[EXT2_N_BLOCKS];/* Pointers to blocks */ 374 __u32 i_generation; /* File version (for NFS) */ 375 __u32 i_file_acl; /* File ACL */ 376 __u32 i_dir_acl; /* Directory ACL */ 377 __u32 i_faddr; /* Fragment address */ 378 union { 379 struct { 380 __u16 l_i_blocks_hi; 381 __u16 i_pad1; 382 __u16 l_i_uid_high; /* these 2 fields */ 383 __u16 l_i_gid_high; /* were reserved2[0] */ 384 __u32 l_i_reserved2; 385 } linux2; 386 struct { 387 __u8 h_i_frag; /* Fragment number */ 388 __u8 h_i_fsize; /* Fragment size */ 389 __u16 h_i_mode_high; 390 __u16 h_i_uid_high; 391 __u16 h_i_gid_high; 392 __u32 h_i_author; 393 } hurd2; 394 } osd2; /* OS dependent 2 */ 395 __u16 i_extra_isize; 396 __u16 i_pad1; 397 __u32 i_ctime_extra; /* extra Change time (nsec << 2 | epoch) */ 398 __u32 i_mtime_extra; /* extra Modification time (nsec << 2 | epoch) */ 399 __u32 i_atime_extra; /* extra Access time (nsec << 2 | epoch) */ 400 __u32 i_crtime; /* File creation time */ 401 __u32 i_crtime_extra; /* extra File creation time (nsec << 2 | epoch)*/ 402}; 403 404#define i_size_high i_dir_acl 405 406#if defined(__KERNEL__) || defined(__linux__) 407#define i_reserved1 osd1.linux1.l_i_reserved1 408#define i_frag osd2.linux2.l_i_frag 409#define i_fsize osd2.linux2.l_i_fsize 410#define i_uid_low i_uid 411#define i_gid_low i_gid 412#define i_uid_high osd2.linux2.l_i_uid_high 413#define i_gid_high osd2.linux2.l_i_gid_high 414#define i_reserved2 osd2.linux2.l_i_reserved2 415#define inode_uid(inode) ((inode).i_uid | (inode).i_uid_high << 16) 416#define inode_gid(inode) ((inode).i_gid | (inode).i_gid_high << 16) 417#else 418#if defined(__GNU__) 419 420#define i_translator osd1.hurd1.h_i_translator 421#define i_frag osd2.hurd2.h_i_frag; 422#define i_fsize osd2.hurd2.h_i_fsize; 423#define i_uid_high osd2.hurd2.h_i_uid_high 424#define i_gid_high osd2.hurd2.h_i_gid_high 425#define i_author osd2.hurd2.h_i_author 426#define inode_uid(inode) ((inode).i_uid | (inode).i_uid_high << 16) 427#define inode_gid(inode) ((inode).i_gid | (inode).i_gid_high << 16) 428 429#endif /* __GNU__ */ 430#endif /* defined(__KERNEL__) || defined(__linux__) */ 431 432/* 433 * File system states 434 */ 435#define EXT2_VALID_FS 0x0001 /* Unmounted cleanly */ 436#define EXT2_ERROR_FS 0x0002 /* Errors detected */ 437 438/* 439 * Misc. filesystem flags 440 */ 441#define EXT2_FLAGS_SIGNED_HASH 0x0001 /* Signed dirhash in use */ 442#define EXT2_FLAGS_UNSIGNED_HASH 0x0002 /* Unsigned dirhash in use */ 443 444/* 445 * Mount flags 446 */ 447#define EXT2_MOUNT_CHECK 0x0001 /* Do mount-time checks */ 448#define EXT2_MOUNT_GRPID 0x0004 /* Create files with directory's group */ 449#define EXT2_MOUNT_DEBUG 0x0008 /* Some debugging messages */ 450#define EXT2_MOUNT_ERRORS_CONT 0x0010 /* Continue on errors */ 451#define EXT2_MOUNT_ERRORS_RO 0x0020 /* Remount fs ro on errors */ 452#define EXT2_MOUNT_ERRORS_PANIC 0x0040 /* Panic on errors */ 453#define EXT2_MOUNT_MINIX_DF 0x0080 /* Mimics the Minix statfs */ 454#define EXT2_MOUNT_NO_UID32 0x0200 /* Disable 32-bit UIDs */ 455 456#define clear_opt(o, opt) o &= ~EXT2_MOUNT_##opt 457#define set_opt(o, opt) o |= EXT2_MOUNT_##opt 458#define test_opt(sb, opt) (EXT2_SB(sb)->s_mount_opt & \ 459 EXT2_MOUNT_##opt) 460/* 461 * Maximal mount counts between two filesystem checks 462 */ 463#define EXT2_DFL_MAX_MNT_COUNT 20 /* Allow 20 mounts */ 464#define EXT2_DFL_CHECKINTERVAL 0 /* Don't use interval check */ 465 466/* 467 * Behaviour when detecting errors 468 */ 469#define EXT2_ERRORS_CONTINUE 1 /* Continue execution */ 470#define EXT2_ERRORS_RO 2 /* Remount fs read-only */ 471#define EXT2_ERRORS_PANIC 3 /* Panic */ 472#define EXT2_ERRORS_DEFAULT EXT2_ERRORS_CONTINUE 473 474/* 475 * Structure of the super block 476 */ 477struct ext2_super_block { 478 __u32 s_inodes_count; /* Inodes count */ 479 __u32 s_blocks_count; /* Blocks count */ 480 __u32 s_r_blocks_count; /* Reserved blocks count */ 481 __u32 s_free_blocks_count; /* Free blocks count */ 482 __u32 s_free_inodes_count; /* Free inodes count */ 483 __u32 s_first_data_block; /* First Data Block */ 484 __u32 s_log_block_size; /* Block size */ 485 __s32 s_log_frag_size; /* Fragment size */ 486 __u32 s_blocks_per_group; /* # Blocks per group */ 487 __u32 s_frags_per_group; /* # Fragments per group */ 488 __u32 s_inodes_per_group; /* # Inodes per group */ 489 __u32 s_mtime; /* Mount time */ 490 __u32 s_wtime; /* Write time */ 491 __u16 s_mnt_count; /* Mount count */ 492 __s16 s_max_mnt_count; /* Maximal mount count */ 493 __u16 s_magic; /* Magic signature */ 494 __u16 s_state; /* File system state */ 495 __u16 s_errors; /* Behaviour when detecting errors */ 496 __u16 s_minor_rev_level; /* minor revision level */ 497 __u32 s_lastcheck; /* time of last check */ 498 __u32 s_checkinterval; /* max. time between checks */ 499 __u32 s_creator_os; /* OS */ 500 __u32 s_rev_level; /* Revision level */ 501 __u16 s_def_resuid; /* Default uid for reserved blocks */ 502 __u16 s_def_resgid; /* Default gid for reserved blocks */ 503 /* 504 * These fields are for EXT2_DYNAMIC_REV superblocks only. 505 * 506 * Note: the difference between the compatible feature set and 507 * the incompatible feature set is that if there is a bit set 508 * in the incompatible feature set that the kernel doesn't 509 * know about, it should refuse to mount the filesystem. 510 * 511 * e2fsck's requirements are more strict; if it doesn't know 512 * about a feature in either the compatible or incompatible 513 * feature set, it must abort and not try to meddle with 514 * things it doesn't understand... 515 */ 516 __u32 s_first_ino; /* First non-reserved inode */ 517 __u16 s_inode_size; /* size of inode structure */ 518 __u16 s_block_group_nr; /* block group # of this superblock */ 519 __u32 s_feature_compat; /* compatible feature set */ 520 __u32 s_feature_incompat; /* incompatible feature set */ 521 __u32 s_feature_ro_compat; /* readonly-compatible feature set */ 522 __u8 s_uuid[16]; /* 128-bit uuid for volume */ 523 char s_volume_name[16]; /* volume name */ 524 char s_last_mounted[64]; /* directory where last mounted */ 525 __u32 s_algorithm_usage_bitmap; /* For compression */ 526 /* 527 * Performance hints. Directory preallocation should only 528 * happen if the EXT2_FEATURE_COMPAT_DIR_PREALLOC flag is on. 529 */ 530 __u8 s_prealloc_blocks; /* Nr of blocks to try to preallocate*/ 531 __u8 s_prealloc_dir_blocks; /* Nr to preallocate for dirs */ 532 __u16 s_reserved_gdt_blocks; /* Per group table for online growth */ 533 /* 534 * Journaling support valid if EXT2_FEATURE_COMPAT_HAS_JOURNAL set. 535 */ 536 __u8 s_journal_uuid[16]; /* uuid of journal superblock */ 537 __u32 s_journal_inum; /* inode number of journal file */ 538 __u32 s_journal_dev; /* device number of journal file */ 539 __u32 s_last_orphan; /* start of list of inodes to delete */ 540 __u32 s_hash_seed[4]; /* HTREE hash seed */ 541 __u8 s_def_hash_version; /* Default hash version to use */ 542 __u8 s_jnl_backup_type; /* Default type of journal backup */ 543 __u16 s_desc_size; /* Group desc. size: INCOMPAT_64BIT */ 544 __u32 s_default_mount_opts; 545 __u32 s_first_meta_bg; /* First metablock group */ 546 __u32 s_mkfs_time; /* When the filesystem was created */ 547 __u32 s_jnl_blocks[17]; /* Backup of the journal inode */ 548 __u32 s_blocks_count_hi; /* Blocks count high 32bits */ 549 __u32 s_r_blocks_count_hi; /* Reserved blocks count high 32 bits*/ 550 __u32 s_free_blocks_hi; /* Free blocks count */ 551 __u16 s_min_extra_isize; /* All inodes have at least # bytes */ 552 __u16 s_want_extra_isize; /* New inodes should reserve # bytes */ 553 __u32 s_flags; /* Miscellaneous flags */ 554 __u16 s_raid_stride; /* RAID stride */ 555 __u16 s_mmp_interval; /* # seconds to wait in MMP checking */ 556 __u64 s_mmp_block; /* Block for multi-mount protection */ 557 __u32 s_raid_stripe_width; /* blocks on all data disks (N*stride)*/ 558 __u32 s_reserved[163]; /* Padding to the end of the block */ 559}; 560 561/* 562 * Codes for operating systems 563 */ 564#define EXT2_OS_LINUX 0 565#define EXT2_OS_HURD 1 566#define EXT2_OBSO_OS_MASIX 2 567#define EXT2_OS_FREEBSD 3 568#define EXT2_OS_LITES 4 569 570/* 571 * Revision levels 572 */ 573#define EXT2_GOOD_OLD_REV 0 /* The good old (original) format */ 574#define EXT2_DYNAMIC_REV 1 /* V2 format w/ dynamic inode sizes */ 575 576#define EXT2_CURRENT_REV EXT2_GOOD_OLD_REV 577#define EXT2_MAX_SUPP_REV EXT2_DYNAMIC_REV 578 579#define EXT2_GOOD_OLD_INODE_SIZE 128 580 581/* 582 * Journal inode backup types 583 */ 584#define EXT3_JNL_BACKUP_BLOCKS 1 585 586/* 587 * Feature set definitions 588 */ 589 590#define EXT2_HAS_COMPAT_FEATURE(sb,mask) \ 591 ( EXT2_SB(sb)->s_feature_compat & (mask) ) 592#define EXT2_HAS_RO_COMPAT_FEATURE(sb,mask) \ 593 ( EXT2_SB(sb)->s_feature_ro_compat & (mask) ) 594#define EXT2_HAS_INCOMPAT_FEATURE(sb,mask) \ 595 ( EXT2_SB(sb)->s_feature_incompat & (mask) ) 596 597#define EXT2_FEATURE_COMPAT_DIR_PREALLOC 0x0001 598#define EXT2_FEATURE_COMPAT_IMAGIC_INODES 0x0002 599#define EXT3_FEATURE_COMPAT_HAS_JOURNAL 0x0004 600#define EXT2_FEATURE_COMPAT_EXT_ATTR 0x0008 601#define EXT2_FEATURE_COMPAT_RESIZE_INODE 0x0010 602#define EXT2_FEATURE_COMPAT_DIR_INDEX 0x0020 603#define EXT2_FEATURE_COMPAT_LAZY_BG 0x0040 604 605#define EXT2_FEATURE_RO_COMPAT_SPARSE_SUPER 0x0001 606#define EXT2_FEATURE_RO_COMPAT_LARGE_FILE 0x0002 607/* #define EXT2_FEATURE_RO_COMPAT_BTREE_DIR 0x0004 not used */ 608#define EXT4_FEATURE_RO_COMPAT_HUGE_FILE 0x0008 609#define EXT4_FEATURE_RO_COMPAT_GDT_CSUM 0x0010 610#define EXT4_FEATURE_RO_COMPAT_DIR_NLINK 0x0020 611#define EXT4_FEATURE_RO_COMPAT_EXTRA_ISIZE 0x0040 612 613#define EXT2_FEATURE_INCOMPAT_COMPRESSION 0x0001 614#define EXT2_FEATURE_INCOMPAT_FILETYPE 0x0002 615#define EXT3_FEATURE_INCOMPAT_RECOVER 0x0004 /* Needs recovery */ 616#define EXT3_FEATURE_INCOMPAT_JOURNAL_DEV 0x0008 /* Journal device */ 617#define EXT2_FEATURE_INCOMPAT_META_BG 0x0010 618#define EXT3_FEATURE_INCOMPAT_EXTENTS 0x0040 619#define EXT4_FEATURE_INCOMPAT_64BIT 0x0080 620#define EXT4_FEATURE_INCOMPAT_MMP 0x0100 621#define EXT4_FEATURE_INCOMPAT_FLEX_BG 0x0200 622 623 624#define EXT2_FEATURE_COMPAT_SUPP 0 625#define EXT2_FEATURE_INCOMPAT_SUPP (EXT2_FEATURE_INCOMPAT_FILETYPE) 626#define EXT2_FEATURE_RO_COMPAT_SUPP (EXT2_FEATURE_RO_COMPAT_SPARSE_SUPER| \ 627 EXT2_FEATURE_RO_COMPAT_LARGE_FILE| \ 628 EXT2_FEATURE_RO_COMPAT_BTREE_DIR) 629 630/* 631 * Default values for user and/or group using reserved blocks 632 */ 633#define EXT2_DEF_RESUID 0 634#define EXT2_DEF_RESGID 0 635 636/* 637 * Default mount options 638 */ 639#define EXT2_DEFM_DEBUG 0x0001 640#define EXT2_DEFM_BSDGROUPS 0x0002 641#define EXT2_DEFM_XATTR_USER 0x0004 642#define EXT2_DEFM_ACL 0x0008 643#define EXT2_DEFM_UID16 0x0010 644#define EXT3_DEFM_JMODE 0x0060 645#define EXT3_DEFM_JMODE_DATA 0x0020 646#define EXT3_DEFM_JMODE_ORDERED 0x0040 647#define EXT3_DEFM_JMODE_WBACK 0x0060 648 649/* 650 * Structure of a directory entry 651 */ 652#define EXT2_NAME_LEN 255 653 654struct ext2_dir_entry { 655 __u32 inode; /* Inode number */ 656 __u16 rec_len; /* Directory entry length */ 657 __u16 name_len; /* Name length */ 658 char name[EXT2_NAME_LEN]; /* File name */ 659}; 660 661/* 662 * The new version of the directory entry. Since EXT2 structures are 663 * stored in intel byte order, and the name_len field could never be 664 * bigger than 255 chars, it's safe to reclaim the extra byte for the 665 * file_type field. 666 */ 667struct ext2_dir_entry_2 { 668 __u32 inode; /* Inode number */ 669 __u16 rec_len; /* Directory entry length */ 670 __u8 name_len; /* Name length */ 671 __u8 file_type; 672 char name[EXT2_NAME_LEN]; /* File name */ 673}; 674 675/* 676 * Ext2 directory file types. Only the low 3 bits are used. The 677 * other bits are reserved for now. 678 */ 679#define EXT2_FT_UNKNOWN 0 680#define EXT2_FT_REG_FILE 1 681#define EXT2_FT_DIR 2 682#define EXT2_FT_CHRDEV 3 683#define EXT2_FT_BLKDEV 4 684#define EXT2_FT_FIFO 5 685#define EXT2_FT_SOCK 6 686#define EXT2_FT_SYMLINK 7 687 688#define EXT2_FT_MAX 8 689 690/* 691 * EXT2_DIR_PAD defines the directory entries boundaries 692 * 693 * NOTE: It must be a multiple of 4 694 */ 695#define EXT2_DIR_PAD 4 696#define EXT2_DIR_ROUND (EXT2_DIR_PAD - 1) 697#define EXT2_DIR_REC_LEN(name_len) (((name_len) + 8 + EXT2_DIR_ROUND) & \ 698 ~EXT2_DIR_ROUND) 699 700/* 701 * This structure will be used for multiple mount protection. It will be 702 * written into the block number saved in the s_mmp_block field in the 703 * superblock. 704 */ 705#define EXT2_MMP_MAGIC 0x004D4D50 /* ASCII for MMP */ 706#define EXT2_MMP_CLEAN 0xFF4D4D50 /* Value of mmp_seq for clean unmount */ 707#define EXT2_MMP_FSCK_ON 0xE24D4D50 /* Value of mmp_seq when being fscked */ 708 709struct mmp_struct { 710 __u32 mmp_magic; 711 __u32 mmp_seq; 712 __u64 mmp_time; 713 char mmp_nodename[64]; 714 char mmp_bdevname[32]; 715 __u16 mmp_interval; 716 __u16 mmp_pad1; 717 __u32 mmp_pad2; 718}; 719 720/* 721 * Interval in number of seconds to update the MMP sequence number. 722 */ 723#define EXT2_MMP_DEF_INTERVAL 5 724 725#endif /* _LINUX_EXT2_FS_H */ 726