ext2_fs.h revision bb767b2fc3b4420f566df6f563574fd8e5c856b1
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#define EXT2_BG_INODE_ZEROED 0x0004 /* On-disk itable initialized to zero */ 177 178/* 179 * Data structures used by the directory indexing feature 180 * 181 * Note: all of the multibyte integer fields are little endian. 182 */ 183 184/* 185 * Note: dx_root_info is laid out so that if it should somehow get 186 * overlaid by a dirent the two low bits of the hash version will be 187 * zero. Therefore, the hash version mod 4 should never be 0. 188 * Sincerely, the paranoia department. 189 */ 190struct ext2_dx_root_info { 191 __u32 reserved_zero; 192 __u8 hash_version; /* 0 now, 1 at release */ 193 __u8 info_length; /* 8 */ 194 __u8 indirect_levels; 195 __u8 unused_flags; 196}; 197 198#define EXT2_HASH_LEGACY 0 199#define EXT2_HASH_HALF_MD4 1 200#define EXT2_HASH_TEA 2 201#define EXT2_HASH_LEGACY_UNSIGNED 3 /* reserved for userspace lib */ 202#define EXT2_HASH_HALF_MD4_UNSIGNED 4 /* reserved for userspace lib */ 203#define EXT2_HASH_TEA_UNSIGNED 5 /* reserved for userspace lib */ 204 205#define EXT2_HASH_FLAG_INCOMPAT 0x1 206 207struct ext2_dx_entry { 208 __u32 hash; 209 __u32 block; 210}; 211 212struct ext2_dx_countlimit { 213 __u16 limit; 214 __u16 count; 215}; 216 217 218/* 219 * Macro-instructions used to manage group descriptors 220 */ 221#define EXT2_MIN_DESC_SIZE 32 222#define EXT2_MIN_DESC_SIZE_64BIT 64 223#define EXT2_MAX_DESC_SIZE EXT2_MIN_BLOCK_SIZE 224#define EXT2_DESC_SIZE(s) \ 225 ((EXT2_SB(s)->s_feature_incompat & EXT4_FEATURE_INCOMPAT_64BIT) ? \ 226 (s)->s_desc_size : EXT2_MIN_DESC_SIZE) 227 228#define EXT2_BLOCKS_PER_GROUP(s) (EXT2_SB(s)->s_blocks_per_group) 229#define EXT2_INODES_PER_GROUP(s) (EXT2_SB(s)->s_inodes_per_group) 230#define EXT2_INODES_PER_BLOCK(s) (EXT2_BLOCK_SIZE(s)/EXT2_INODE_SIZE(s)) 231/* limits imposed by 16-bit value gd_free_{blocks,inode}_count */ 232#define EXT2_MAX_BLOCKS_PER_GROUP(s) ((1 << 16) - 8) 233#define EXT2_MAX_INODES_PER_GROUP(s) ((1 << 16) - EXT2_INODES_PER_BLOCK(s)) 234#ifdef __KERNEL__ 235#define EXT2_DESC_PER_BLOCK(s) (EXT2_SB(s)->s_desc_per_block) 236#define EXT2_DESC_PER_BLOCK_BITS(s) (EXT2_SB(s)->s_desc_per_block_bits) 237#else 238#define EXT2_DESC_PER_BLOCK(s) (EXT2_BLOCK_SIZE(s) / EXT2_DESC_SIZE(s)) 239#endif 240 241/* 242 * Constants relative to the data blocks 243 */ 244#define EXT2_NDIR_BLOCKS 12 245#define EXT2_IND_BLOCK EXT2_NDIR_BLOCKS 246#define EXT2_DIND_BLOCK (EXT2_IND_BLOCK + 1) 247#define EXT2_TIND_BLOCK (EXT2_DIND_BLOCK + 1) 248#define EXT2_N_BLOCKS (EXT2_TIND_BLOCK + 1) 249 250/* 251 * Inode flags 252 */ 253#define EXT2_SECRM_FL 0x00000001 /* Secure deletion */ 254#define EXT2_UNRM_FL 0x00000002 /* Undelete */ 255#define EXT2_COMPR_FL 0x00000004 /* Compress file */ 256#define EXT2_SYNC_FL 0x00000008 /* Synchronous updates */ 257#define EXT2_IMMUTABLE_FL 0x00000010 /* Immutable file */ 258#define EXT2_APPEND_FL 0x00000020 /* writes to file may only append */ 259#define EXT2_NODUMP_FL 0x00000040 /* do not dump file */ 260#define EXT2_NOATIME_FL 0x00000080 /* do not update atime */ 261/* Reserved for compression usage... */ 262#define EXT2_DIRTY_FL 0x00000100 263#define EXT2_COMPRBLK_FL 0x00000200 /* One or more compressed clusters */ 264#define EXT2_NOCOMPR_FL 0x00000400 /* Access raw compressed data */ 265#define EXT2_ECOMPR_FL 0x00000800 /* Compression error */ 266/* End compression flags --- maybe not all used */ 267#define EXT2_BTREE_FL 0x00001000 /* btree format dir */ 268#define EXT2_INDEX_FL 0x00001000 /* hash-indexed directory */ 269#define EXT2_IMAGIC_FL 0x00002000 270#define EXT3_JOURNAL_DATA_FL 0x00004000 /* file data should be journaled */ 271#define EXT2_NOTAIL_FL 0x00008000 /* file tail should not be merged */ 272#define EXT2_DIRSYNC_FL 0x00010000 /* Synchronous directory modifications */ 273#define EXT2_TOPDIR_FL 0x00020000 /* Top of directory hierarchies*/ 274#define EXT4_HUGE_FILE_FL 0x00040000 /* Set to each huge file */ 275#define EXT4_EXTENTS_FL 0x00080000 /* Inode uses extents */ 276#define EXT2_RESERVED_FL 0x80000000 /* reserved for ext2 lib */ 277 278#define EXT2_FL_USER_VISIBLE 0x000BDFFF /* User visible flags */ 279#define EXT2_FL_USER_MODIFIABLE 0x000080FF /* User modifiable flags */ 280 281/* 282 * ioctl commands 283 */ 284 285/* Used for online resize */ 286struct ext2_new_group_input { 287 __u32 group; /* Group number for this data */ 288 __u32 block_bitmap; /* Absolute block number of block bitmap */ 289 __u32 inode_bitmap; /* Absolute block number of inode bitmap */ 290 __u32 inode_table; /* Absolute block number of inode table start */ 291 __u32 blocks_count; /* Total number of blocks in this group */ 292 __u16 reserved_blocks; /* Number of reserved blocks in this group */ 293 __u16 unused; /* Number of reserved GDT blocks in group */ 294}; 295 296#ifdef __GNU__ /* Needed for the Hurd */ 297#define _IOT_ext2_new_group_input _IOT (_IOTS(__u32), 5, _IOTS(__u16), 2, 0, 0) 298#endif 299 300#define EXT2_IOC_GETFLAGS _IOR('f', 1, long) 301#define EXT2_IOC_SETFLAGS _IOW('f', 2, long) 302#define EXT2_IOC_GETVERSION _IOR('v', 1, long) 303#define EXT2_IOC_SETVERSION _IOW('v', 2, long) 304#define EXT2_IOC_GETVERSION_NEW _IOR('f', 3, long) 305#define EXT2_IOC_SETVERSION_NEW _IOW('f', 4, long) 306#define EXT2_IOC_GROUP_EXTEND _IOW('f', 7, unsigned long) 307#define EXT2_IOC_GROUP_ADD _IOW('f', 8,struct ext2_new_group_input) 308 309/* 310 * Structure of an inode on the disk 311 */ 312struct ext2_inode { 313 __u16 i_mode; /* File mode */ 314 __u16 i_uid; /* Low 16 bits of Owner Uid */ 315 __u32 i_size; /* Size in bytes */ 316 __u32 i_atime; /* Access time */ 317 __u32 i_ctime; /* Inode change time */ 318 __u32 i_mtime; /* Modification time */ 319 __u32 i_dtime; /* Deletion Time */ 320 __u16 i_gid; /* Low 16 bits of Group Id */ 321 __u16 i_links_count; /* Links count */ 322 __u32 i_blocks; /* Blocks count */ 323 __u32 i_flags; /* File flags */ 324 union { 325 struct { 326 __u32 l_i_version; /* was l_i_reserved1 */ 327 } linux1; 328 struct { 329 __u32 h_i_translator; 330 } hurd1; 331 } osd1; /* OS dependent 1 */ 332 __u32 i_block[EXT2_N_BLOCKS];/* Pointers to blocks */ 333 __u32 i_generation; /* File version (for NFS) */ 334 __u32 i_file_acl; /* File ACL */ 335 __u32 i_dir_acl; /* Directory ACL */ 336 __u32 i_faddr; /* Fragment address */ 337 union { 338 struct { 339 __u16 l_i_blocks_hi; 340 __u16 l_i_file_acl_high; 341 __u16 l_i_uid_high; /* these 2 fields */ 342 __u16 l_i_gid_high; /* were reserved2[0] */ 343 __u32 l_i_reserved2; 344 } linux2; 345 struct { 346 __u8 h_i_frag; /* Fragment number */ 347 __u8 h_i_fsize; /* Fragment size */ 348 __u16 h_i_mode_high; 349 __u16 h_i_uid_high; 350 __u16 h_i_gid_high; 351 __u32 h_i_author; 352 } hurd2; 353 } osd2; /* OS dependent 2 */ 354}; 355 356/* 357 * Permanent part of an large inode on the disk 358 */ 359struct ext2_inode_large { 360 __u16 i_mode; /* File mode */ 361 __u16 i_uid; /* Low 16 bits of Owner Uid */ 362 __u32 i_size; /* Size in bytes */ 363 __u32 i_atime; /* Access time */ 364 __u32 i_ctime; /* Inode Change time */ 365 __u32 i_mtime; /* Modification time */ 366 __u32 i_dtime; /* Deletion Time */ 367 __u16 i_gid; /* Low 16 bits of Group Id */ 368 __u16 i_links_count; /* Links count */ 369 __u32 i_blocks; /* Blocks count */ 370 __u32 i_flags; /* File flags */ 371 union { 372 struct { 373 __u32 l_i_version; /* was l_i_reserved1 */ 374 } linux1; 375 struct { 376 __u32 h_i_translator; 377 } hurd1; 378 } osd1; /* OS dependent 1 */ 379 __u32 i_block[EXT2_N_BLOCKS];/* Pointers to blocks */ 380 __u32 i_generation; /* File version (for NFS) */ 381 __u32 i_file_acl; /* File ACL */ 382 __u32 i_dir_acl; /* Directory ACL */ 383 __u32 i_faddr; /* Fragment address */ 384 union { 385 struct { 386 __u16 l_i_blocks_hi; 387 __u16 l_i_file_acl_high; 388 __u16 l_i_uid_high; /* these 2 fields */ 389 __u16 l_i_gid_high; /* were reserved2[0] */ 390 __u32 l_i_reserved2; 391 } linux2; 392 struct { 393 __u8 h_i_frag; /* Fragment number */ 394 __u8 h_i_fsize; /* Fragment size */ 395 __u16 h_i_mode_high; 396 __u16 h_i_uid_high; 397 __u16 h_i_gid_high; 398 __u32 h_i_author; 399 } hurd2; 400 } osd2; /* OS dependent 2 */ 401 __u16 i_extra_isize; 402 __u16 i_pad1; 403 __u32 i_ctime_extra; /* extra Change time (nsec << 2 | epoch) */ 404 __u32 i_mtime_extra; /* extra Modification time (nsec << 2 | epoch) */ 405 __u32 i_atime_extra; /* extra Access time (nsec << 2 | epoch) */ 406 __u32 i_crtime; /* File creation time */ 407 __u32 i_crtime_extra; /* extra File creation time (nsec << 2 | epoch)*/ 408 __u32 i_version_hi; /* high 32 bits for 64-bit version */ 409}; 410 411#define i_size_high i_dir_acl 412 413#if defined(__KERNEL__) || defined(__linux__) 414#define i_reserved1 osd1.linux1.l_i_reserved1 415#define i_frag osd2.linux2.l_i_frag 416#define i_fsize osd2.linux2.l_i_fsize 417#define i_uid_low i_uid 418#define i_gid_low i_gid 419#define i_uid_high osd2.linux2.l_i_uid_high 420#define i_gid_high osd2.linux2.l_i_gid_high 421#define i_reserved2 osd2.linux2.l_i_reserved2 422#else 423#if defined(__GNU__) 424 425#define i_translator osd1.hurd1.h_i_translator 426#define i_frag osd2.hurd2.h_i_frag; 427#define i_fsize osd2.hurd2.h_i_fsize; 428#define i_uid_high osd2.hurd2.h_i_uid_high 429#define i_gid_high osd2.hurd2.h_i_gid_high 430#define i_author osd2.hurd2.h_i_author 431 432#endif /* __GNU__ */ 433#endif /* defined(__KERNEL__) || defined(__linux__) */ 434 435#define inode_uid(inode) ((inode).i_uid | (inode).osd2.linux2.l_i_uid_high << 16) 436#define inode_gid(inode) ((inode).i_gid | (inode).osd2.linux2.l_i_gid_high << 16) 437#define ext2fs_set_i_uid_high(inode,x) ((inode).osd2.linux2.l_i_uid_high = (x)) 438#define ext2fs_set_i_gid_high(inode,x) ((inode).osd2.linux2.l_i_gid_high = (x)) 439 440/* 441 * File system states 442 */ 443#define EXT2_VALID_FS 0x0001 /* Unmounted cleanly */ 444#define EXT2_ERROR_FS 0x0002 /* Errors detected */ 445#define EXT3_ORPHAN_FS 0x0004 /* Orphans being recovered */ 446 447/* 448 * Misc. filesystem flags 449 */ 450#define EXT2_FLAGS_SIGNED_HASH 0x0001 /* Signed dirhash in use */ 451#define EXT2_FLAGS_UNSIGNED_HASH 0x0002 /* Unsigned dirhash in use */ 452#define EXT2_FLAGS_TEST_FILESYS 0x0004 /* OK for use on development code */ 453 454/* 455 * Mount flags 456 */ 457#define EXT2_MOUNT_CHECK 0x0001 /* Do mount-time checks */ 458#define EXT2_MOUNT_GRPID 0x0004 /* Create files with directory's group */ 459#define EXT2_MOUNT_DEBUG 0x0008 /* Some debugging messages */ 460#define EXT2_MOUNT_ERRORS_CONT 0x0010 /* Continue on errors */ 461#define EXT2_MOUNT_ERRORS_RO 0x0020 /* Remount fs ro on errors */ 462#define EXT2_MOUNT_ERRORS_PANIC 0x0040 /* Panic on errors */ 463#define EXT2_MOUNT_MINIX_DF 0x0080 /* Mimics the Minix statfs */ 464#define EXT2_MOUNT_NO_UID32 0x0200 /* Disable 32-bit UIDs */ 465 466#define clear_opt(o, opt) o &= ~EXT2_MOUNT_##opt 467#define set_opt(o, opt) o |= EXT2_MOUNT_##opt 468#define test_opt(sb, opt) (EXT2_SB(sb)->s_mount_opt & \ 469 EXT2_MOUNT_##opt) 470/* 471 * Maximal mount counts between two filesystem checks 472 */ 473#define EXT2_DFL_MAX_MNT_COUNT 20 /* Allow 20 mounts */ 474#define EXT2_DFL_CHECKINTERVAL 0 /* Don't use interval check */ 475 476/* 477 * Behaviour when detecting errors 478 */ 479#define EXT2_ERRORS_CONTINUE 1 /* Continue execution */ 480#define EXT2_ERRORS_RO 2 /* Remount fs read-only */ 481#define EXT2_ERRORS_PANIC 3 /* Panic */ 482#define EXT2_ERRORS_DEFAULT EXT2_ERRORS_CONTINUE 483 484/* 485 * Structure of the super block 486 */ 487struct ext2_super_block { 488 __u32 s_inodes_count; /* Inodes count */ 489 __u32 s_blocks_count; /* Blocks count */ 490 __u32 s_r_blocks_count; /* Reserved blocks count */ 491 __u32 s_free_blocks_count; /* Free blocks count */ 492 __u32 s_free_inodes_count; /* Free inodes count */ 493 __u32 s_first_data_block; /* First Data Block */ 494 __u32 s_log_block_size; /* Block size */ 495 __s32 s_log_frag_size; /* Fragment size */ 496 __u32 s_blocks_per_group; /* # Blocks per group */ 497 __u32 s_frags_per_group; /* # Fragments per group */ 498 __u32 s_inodes_per_group; /* # Inodes per group */ 499 __u32 s_mtime; /* Mount time */ 500 __u32 s_wtime; /* Write time */ 501 __u16 s_mnt_count; /* Mount count */ 502 __s16 s_max_mnt_count; /* Maximal mount count */ 503 __u16 s_magic; /* Magic signature */ 504 __u16 s_state; /* File system state */ 505 __u16 s_errors; /* Behaviour when detecting errors */ 506 __u16 s_minor_rev_level; /* minor revision level */ 507 __u32 s_lastcheck; /* time of last check */ 508 __u32 s_checkinterval; /* max. time between checks */ 509 __u32 s_creator_os; /* OS */ 510 __u32 s_rev_level; /* Revision level */ 511 __u16 s_def_resuid; /* Default uid for reserved blocks */ 512 __u16 s_def_resgid; /* Default gid for reserved blocks */ 513 /* 514 * These fields are for EXT2_DYNAMIC_REV superblocks only. 515 * 516 * Note: the difference between the compatible feature set and 517 * the incompatible feature set is that if there is a bit set 518 * in the incompatible feature set that the kernel doesn't 519 * know about, it should refuse to mount the filesystem. 520 * 521 * e2fsck's requirements are more strict; if it doesn't know 522 * about a feature in either the compatible or incompatible 523 * feature set, it must abort and not try to meddle with 524 * things it doesn't understand... 525 */ 526 __u32 s_first_ino; /* First non-reserved inode */ 527 __u16 s_inode_size; /* size of inode structure */ 528 __u16 s_block_group_nr; /* block group # of this superblock */ 529 __u32 s_feature_compat; /* compatible feature set */ 530 __u32 s_feature_incompat; /* incompatible feature set */ 531 __u32 s_feature_ro_compat; /* readonly-compatible feature set */ 532 __u8 s_uuid[16]; /* 128-bit uuid for volume */ 533 char s_volume_name[16]; /* volume name */ 534 char s_last_mounted[64]; /* directory where last mounted */ 535 __u32 s_algorithm_usage_bitmap; /* For compression */ 536 /* 537 * Performance hints. Directory preallocation should only 538 * happen if the EXT2_FEATURE_COMPAT_DIR_PREALLOC flag is on. 539 */ 540 __u8 s_prealloc_blocks; /* Nr of blocks to try to preallocate*/ 541 __u8 s_prealloc_dir_blocks; /* Nr to preallocate for dirs */ 542 __u16 s_reserved_gdt_blocks; /* Per group table for online growth */ 543 /* 544 * Journaling support valid if EXT2_FEATURE_COMPAT_HAS_JOURNAL set. 545 */ 546 __u8 s_journal_uuid[16]; /* uuid of journal superblock */ 547 __u32 s_journal_inum; /* inode number of journal file */ 548 __u32 s_journal_dev; /* device number of journal file */ 549 __u32 s_last_orphan; /* start of list of inodes to delete */ 550 __u32 s_hash_seed[4]; /* HTREE hash seed */ 551 __u8 s_def_hash_version; /* Default hash version to use */ 552 __u8 s_jnl_backup_type; /* Default type of journal backup */ 553 __u16 s_desc_size; /* Group desc. size: INCOMPAT_64BIT */ 554 __u32 s_default_mount_opts; 555 __u32 s_first_meta_bg; /* First metablock group */ 556 __u32 s_mkfs_time; /* When the filesystem was created */ 557 __u32 s_jnl_blocks[17]; /* Backup of the journal inode */ 558 __u32 s_blocks_count_hi; /* Blocks count high 32bits */ 559 __u32 s_r_blocks_count_hi; /* Reserved blocks count high 32 bits*/ 560 __u32 s_free_blocks_hi; /* Free blocks count */ 561 __u16 s_min_extra_isize; /* All inodes have at least # bytes */ 562 __u16 s_want_extra_isize; /* New inodes should reserve # bytes */ 563 __u32 s_flags; /* Miscellaneous flags */ 564 __u16 s_raid_stride; /* RAID stride */ 565 __u16 s_mmp_interval; /* # seconds to wait in MMP checking */ 566 __u64 s_mmp_block; /* Block for multi-mount protection */ 567 __u32 s_raid_stripe_width; /* blocks on all data disks (N*stride)*/ 568 __u8 s_log_groups_per_flex; /* FLEX_BG group size */ 569 __u8 s_reserved_char_pad; 570 __u16 s_reserved_pad; /* Padding to next 32bits */ 571 __u32 s_reserved[162]; /* Padding to the end of the block */ 572}; 573 574/* 575 * Codes for operating systems 576 */ 577#define EXT2_OS_LINUX 0 578#define EXT2_OS_HURD 1 579#define EXT2_OBSO_OS_MASIX 2 580#define EXT2_OS_FREEBSD 3 581#define EXT2_OS_LITES 4 582 583/* 584 * Revision levels 585 */ 586#define EXT2_GOOD_OLD_REV 0 /* The good old (original) format */ 587#define EXT2_DYNAMIC_REV 1 /* V2 format w/ dynamic inode sizes */ 588 589#define EXT2_CURRENT_REV EXT2_GOOD_OLD_REV 590#define EXT2_MAX_SUPP_REV EXT2_DYNAMIC_REV 591 592#define EXT2_GOOD_OLD_INODE_SIZE 128 593 594/* 595 * Journal inode backup types 596 */ 597#define EXT3_JNL_BACKUP_BLOCKS 1 598 599/* 600 * Feature set definitions 601 */ 602 603#define EXT2_HAS_COMPAT_FEATURE(sb,mask) \ 604 ( EXT2_SB(sb)->s_feature_compat & (mask) ) 605#define EXT2_HAS_RO_COMPAT_FEATURE(sb,mask) \ 606 ( EXT2_SB(sb)->s_feature_ro_compat & (mask) ) 607#define EXT2_HAS_INCOMPAT_FEATURE(sb,mask) \ 608 ( EXT2_SB(sb)->s_feature_incompat & (mask) ) 609 610#define EXT2_FEATURE_COMPAT_DIR_PREALLOC 0x0001 611#define EXT2_FEATURE_COMPAT_IMAGIC_INODES 0x0002 612#define EXT3_FEATURE_COMPAT_HAS_JOURNAL 0x0004 613#define EXT2_FEATURE_COMPAT_EXT_ATTR 0x0008 614#define EXT2_FEATURE_COMPAT_RESIZE_INODE 0x0010 615#define EXT2_FEATURE_COMPAT_DIR_INDEX 0x0020 616#define EXT2_FEATURE_COMPAT_LAZY_BG 0x0040 617 618#define EXT2_FEATURE_RO_COMPAT_SPARSE_SUPER 0x0001 619#define EXT2_FEATURE_RO_COMPAT_LARGE_FILE 0x0002 620/* #define EXT2_FEATURE_RO_COMPAT_BTREE_DIR 0x0004 not used */ 621#define EXT4_FEATURE_RO_COMPAT_HUGE_FILE 0x0008 622#define EXT4_FEATURE_RO_COMPAT_GDT_CSUM 0x0010 623#define EXT4_FEATURE_RO_COMPAT_DIR_NLINK 0x0020 624#define EXT4_FEATURE_RO_COMPAT_EXTRA_ISIZE 0x0040 625 626#define EXT2_FEATURE_INCOMPAT_COMPRESSION 0x0001 627#define EXT2_FEATURE_INCOMPAT_FILETYPE 0x0002 628#define EXT3_FEATURE_INCOMPAT_RECOVER 0x0004 /* Needs recovery */ 629#define EXT3_FEATURE_INCOMPAT_JOURNAL_DEV 0x0008 /* Journal device */ 630#define EXT2_FEATURE_INCOMPAT_META_BG 0x0010 631#define EXT3_FEATURE_INCOMPAT_EXTENTS 0x0040 632#define EXT4_FEATURE_INCOMPAT_64BIT 0x0080 633#define EXT4_FEATURE_INCOMPAT_MMP 0x0100 634#define EXT4_FEATURE_INCOMPAT_FLEX_BG 0x0200 635 636 637#define EXT2_FEATURE_COMPAT_SUPP 0 638#define EXT2_FEATURE_INCOMPAT_SUPP (EXT2_FEATURE_INCOMPAT_FILETYPE) 639#define EXT2_FEATURE_RO_COMPAT_SUPP (EXT2_FEATURE_RO_COMPAT_SPARSE_SUPER| \ 640 EXT2_FEATURE_RO_COMPAT_LARGE_FILE| \ 641 EXT4_FEATURE_RO_COMPAT_DIR_NLINK| \ 642 EXT2_FEATURE_RO_COMPAT_BTREE_DIR) 643 644/* 645 * Default values for user and/or group using reserved blocks 646 */ 647#define EXT2_DEF_RESUID 0 648#define EXT2_DEF_RESGID 0 649 650/* 651 * Default mount options 652 */ 653#define EXT2_DEFM_DEBUG 0x0001 654#define EXT2_DEFM_BSDGROUPS 0x0002 655#define EXT2_DEFM_XATTR_USER 0x0004 656#define EXT2_DEFM_ACL 0x0008 657#define EXT2_DEFM_UID16 0x0010 658#define EXT3_DEFM_JMODE 0x0060 659#define EXT3_DEFM_JMODE_DATA 0x0020 660#define EXT3_DEFM_JMODE_ORDERED 0x0040 661#define EXT3_DEFM_JMODE_WBACK 0x0060 662 663/* 664 * Structure of a directory entry 665 */ 666#define EXT2_NAME_LEN 255 667 668struct ext2_dir_entry { 669 __u32 inode; /* Inode number */ 670 __u16 rec_len; /* Directory entry length */ 671 __u16 name_len; /* Name length */ 672 char name[EXT2_NAME_LEN]; /* File name */ 673}; 674 675/* 676 * The new version of the directory entry. Since EXT2 structures are 677 * stored in intel byte order, and the name_len field could never be 678 * bigger than 255 chars, it's safe to reclaim the extra byte for the 679 * file_type field. 680 */ 681struct ext2_dir_entry_2 { 682 __u32 inode; /* Inode number */ 683 __u16 rec_len; /* Directory entry length */ 684 __u8 name_len; /* Name length */ 685 __u8 file_type; 686 char name[EXT2_NAME_LEN]; /* File name */ 687}; 688 689/* 690 * Ext2 directory file types. Only the low 3 bits are used. The 691 * other bits are reserved for now. 692 */ 693#define EXT2_FT_UNKNOWN 0 694#define EXT2_FT_REG_FILE 1 695#define EXT2_FT_DIR 2 696#define EXT2_FT_CHRDEV 3 697#define EXT2_FT_BLKDEV 4 698#define EXT2_FT_FIFO 5 699#define EXT2_FT_SOCK 6 700#define EXT2_FT_SYMLINK 7 701 702#define EXT2_FT_MAX 8 703 704/* 705 * EXT2_DIR_PAD defines the directory entries boundaries 706 * 707 * NOTE: It must be a multiple of 4 708 */ 709#define EXT2_DIR_PAD 4 710#define EXT2_DIR_ROUND (EXT2_DIR_PAD - 1) 711#define EXT2_DIR_REC_LEN(name_len) (((name_len) + 8 + EXT2_DIR_ROUND) & \ 712 ~EXT2_DIR_ROUND) 713 714/* 715 * This structure will be used for multiple mount protection. It will be 716 * written into the block number saved in the s_mmp_block field in the 717 * superblock. 718 */ 719#define EXT2_MMP_MAGIC 0x004D4D50 /* ASCII for MMP */ 720#define EXT2_MMP_CLEAN 0xFF4D4D50 /* Value of mmp_seq for clean unmount */ 721#define EXT2_MMP_FSCK_ON 0xE24D4D50 /* Value of mmp_seq when being fscked */ 722 723struct mmp_struct { 724 __u32 mmp_magic; 725 __u32 mmp_seq; 726 __u64 mmp_time; 727 char mmp_nodename[64]; 728 char mmp_bdevname[32]; 729 __u16 mmp_interval; 730 __u16 mmp_pad1; 731 __u32 mmp_pad2; 732}; 733 734/* 735 * Interval in number of seconds to update the MMP sequence number. 736 */ 737#define EXT2_MMP_DEF_INTERVAL 5 738 739#endif /* _LINUX_EXT2_FS_H */ 740