ext2_fs.h revision b62e88af6a1be97b224a3e5c1fea43fa173567ea
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_BLOCKS_PER_GROUP(s) (EXT2_SB(s)->s_blocks_per_group) 221#define EXT2_INODES_PER_GROUP(s) (EXT2_SB(s)->s_inodes_per_group) 222#define EXT2_INODES_PER_BLOCK(s) (EXT2_BLOCK_SIZE(s)/EXT2_INODE_SIZE(s)) 223/* limits imposed by 16-bit value gd_free_{blocks,inode}_count */ 224#define EXT2_MAX_BLOCKS_PER_GROUP(s) ((1 << 16) - 8) 225#define EXT2_MAX_INODES_PER_GROUP(s) ((1 << 16) - EXT2_INODES_PER_BLOCK(s)) 226#ifdef __KERNEL__ 227#define EXT2_DESC_PER_BLOCK(s) (EXT2_SB(s)->s_desc_per_block) 228#define EXT2_DESC_PER_BLOCK_BITS(s) (EXT2_SB(s)->s_desc_per_block_bits) 229#else 230#define EXT2_DESC_PER_BLOCK(s) (EXT2_BLOCK_SIZE(s) / sizeof (struct ext2_group_desc)) 231#endif 232 233/* 234 * Constants relative to the data blocks 235 */ 236#define EXT2_NDIR_BLOCKS 12 237#define EXT2_IND_BLOCK EXT2_NDIR_BLOCKS 238#define EXT2_DIND_BLOCK (EXT2_IND_BLOCK + 1) 239#define EXT2_TIND_BLOCK (EXT2_DIND_BLOCK + 1) 240#define EXT2_N_BLOCKS (EXT2_TIND_BLOCK + 1) 241 242/* 243 * Inode flags 244 */ 245#define EXT2_SECRM_FL 0x00000001 /* Secure deletion */ 246#define EXT2_UNRM_FL 0x00000002 /* Undelete */ 247#define EXT2_COMPR_FL 0x00000004 /* Compress file */ 248#define EXT2_SYNC_FL 0x00000008 /* Synchronous updates */ 249#define EXT2_IMMUTABLE_FL 0x00000010 /* Immutable file */ 250#define EXT2_APPEND_FL 0x00000020 /* writes to file may only append */ 251#define EXT2_NODUMP_FL 0x00000040 /* do not dump file */ 252#define EXT2_NOATIME_FL 0x00000080 /* do not update atime */ 253/* Reserved for compression usage... */ 254#define EXT2_DIRTY_FL 0x00000100 255#define EXT2_COMPRBLK_FL 0x00000200 /* One or more compressed clusters */ 256#define EXT2_NOCOMPR_FL 0x00000400 /* Access raw compressed data */ 257#define EXT2_ECOMPR_FL 0x00000800 /* Compression error */ 258/* End compression flags --- maybe not all used */ 259#define EXT2_BTREE_FL 0x00001000 /* btree format dir */ 260#define EXT2_INDEX_FL 0x00001000 /* hash-indexed directory */ 261#define EXT2_IMAGIC_FL 0x00002000 262#define EXT3_JOURNAL_DATA_FL 0x00004000 /* file data should be journaled */ 263#define EXT2_NOTAIL_FL 0x00008000 /* file tail should not be merged */ 264#define EXT2_DIRSYNC_FL 0x00010000 /* Synchronous directory modifications */ 265#define EXT2_TOPDIR_FL 0x00020000 /* Top of directory hierarchies*/ 266#define EXT4_EXTENTS_FL 0x00080000 /* Inode uses extents */ 267#define EXT2_RESERVED_FL 0x80000000 /* reserved for ext2 lib */ 268 269#define EXT2_FL_USER_VISIBLE 0x000BDFFF /* User visible flags */ 270#define EXT2_FL_USER_MODIFIABLE 0x000080FF /* User modifiable flags */ 271 272/* 273 * ioctl commands 274 */ 275 276/* Used for online resize */ 277struct ext2_new_group_input { 278 __u32 group; /* Group number for this data */ 279 __u32 block_bitmap; /* Absolute block number of block bitmap */ 280 __u32 inode_bitmap; /* Absolute block number of inode bitmap */ 281 __u32 inode_table; /* Absolute block number of inode table start */ 282 __u32 blocks_count; /* Total number of blocks in this group */ 283 __u16 reserved_blocks; /* Number of reserved blocks in this group */ 284 __u16 unused; /* Number of reserved GDT blocks in group */ 285}; 286 287#define EXT2_IOC_GETFLAGS _IOR('f', 1, long) 288#define EXT2_IOC_SETFLAGS _IOW('f', 2, long) 289#define EXT2_IOC_GETVERSION _IOR('v', 1, long) 290#define EXT2_IOC_SETVERSION _IOW('v', 2, long) 291#define EXT2_IOC_GETVERSION_NEW _IOR('f', 3, long) 292#define EXT2_IOC_SETVERSION_NEW _IOW('f', 4, long) 293#define EXT2_IOC_GROUP_EXTEND _IOW('f', 7, unsigned long) 294#define EXT2_IOC_GROUP_ADD _IOW('f', 8,struct ext2_new_group_input) 295 296/* 297 * Structure of an inode on the disk 298 */ 299struct ext2_inode { 300 __u16 i_mode; /* File mode */ 301 __u16 i_uid; /* Low 16 bits of Owner Uid */ 302 __u32 i_size; /* Size in bytes */ 303 __u32 i_atime; /* Access time */ 304 __u32 i_ctime; /* Inode change time */ 305 __u32 i_mtime; /* Modification time */ 306 __u32 i_dtime; /* Deletion Time */ 307 __u16 i_gid; /* Low 16 bits of Group Id */ 308 __u16 i_links_count; /* Links count */ 309 __u32 i_blocks; /* Blocks count */ 310 __u32 i_flags; /* File flags */ 311 union { 312 struct { 313 __u32 l_i_version; /* was l_i_reserved1 */ 314 } linux1; 315 struct { 316 __u32 h_i_translator; 317 } hurd1; 318 struct { 319 __u32 m_i_reserved1; 320 } masix1; 321 } osd1; /* OS dependent 1 */ 322 __u32 i_block[EXT2_N_BLOCKS];/* Pointers to blocks */ 323 __u32 i_generation; /* File version (for NFS) */ 324 __u32 i_file_acl; /* File ACL */ 325 __u32 i_dir_acl; /* Directory ACL */ 326 __u32 i_faddr; /* Fragment address */ 327 union { 328 struct { 329 __u16 l_i_blocks_hi; 330 __u16 i_pad1; 331 __u16 l_i_uid_high; /* these 2 fields */ 332 __u16 l_i_gid_high; /* were reserved2[0] */ 333 __u32 l_i_reserved2; 334 } linux2; 335 struct { 336 __u8 h_i_frag; /* Fragment number */ 337 __u8 h_i_fsize; /* Fragment size */ 338 __u16 h_i_mode_high; 339 __u16 h_i_uid_high; 340 __u16 h_i_gid_high; 341 __u32 h_i_author; 342 } hurd2; 343 struct { 344 __u8 m_i_frag; /* Fragment number */ 345 __u8 m_i_fsize; /* Fragment size */ 346 __u16 m_pad1; 347 __u32 m_i_reserved2[2]; 348 } masix2; 349 } osd2; /* OS dependent 2 */ 350}; 351 352/* 353 * Permanent part of an large inode on the disk 354 */ 355struct ext2_inode_large { 356 __u16 i_mode; /* File mode */ 357 __u16 i_uid; /* Low 16 bits of Owner Uid */ 358 __u32 i_size; /* Size in bytes */ 359 __u32 i_atime; /* Access time */ 360 __u32 i_ctime; /* Inode Change time */ 361 __u32 i_mtime; /* Modification time */ 362 __u32 i_dtime; /* Deletion Time */ 363 __u16 i_gid; /* Low 16 bits of Group Id */ 364 __u16 i_links_count; /* Links count */ 365 __u32 i_blocks; /* Blocks count */ 366 __u32 i_flags; /* File flags */ 367 union { 368 struct { 369 __u32 l_i_version; /* was l_i_reserved1 */ 370 } linux1; 371 struct { 372 __u32 h_i_translator; 373 } hurd1; 374 struct { 375 __u32 m_i_reserved1; 376 } masix1; 377 } osd1; /* OS dependent 1 */ 378 __u32 i_block[EXT2_N_BLOCKS];/* Pointers to blocks */ 379 __u32 i_generation; /* File version (for NFS) */ 380 __u32 i_file_acl; /* File ACL */ 381 __u32 i_dir_acl; /* Directory ACL */ 382 __u32 i_faddr; /* Fragment address */ 383 union { 384 struct { 385 __u16 l_i_blocks_hi; 386 __u16 i_pad1; 387 __u16 l_i_uid_high; /* these 2 fields */ 388 __u16 l_i_gid_high; /* were reserved2[0] */ 389 __u32 l_i_reserved2; 390 } linux2; 391 struct { 392 __u8 h_i_frag; /* Fragment number */ 393 __u8 h_i_fsize; /* Fragment size */ 394 __u16 h_i_mode_high; 395 __u16 h_i_uid_high; 396 __u16 h_i_gid_high; 397 __u32 h_i_author; 398 } hurd2; 399 struct { 400 __u8 m_i_frag; /* Fragment number */ 401 __u8 m_i_fsize; /* Fragment size */ 402 __u16 m_pad1; 403 __u32 m_i_reserved2[2]; 404 } masix2; 405 } osd2; /* OS dependent 2 */ 406 __u16 i_extra_isize; 407 __u16 i_pad1; 408 __u32 i_ctime_extra; /* extra Change time (nsec << 2 | epoch) */ 409 __u32 i_mtime_extra; /* extra Modification time (nsec << 2 | epoch) */ 410 __u32 i_atime_extra; /* extra Access time (nsec << 2 | epoch) */ 411 __u32 i_crtime; /* File creation time */ 412 __u32 i_crtime_extra; /* extra File creation time (nsec << 2 | epoch)*/ 413}; 414 415#define i_size_high i_dir_acl 416 417#if defined(__KERNEL__) || defined(__linux__) 418#define i_reserved1 osd1.linux1.l_i_reserved1 419#define i_frag osd2.linux2.l_i_frag 420#define i_fsize osd2.linux2.l_i_fsize 421#define i_uid_low i_uid 422#define i_gid_low i_gid 423#define i_uid_high osd2.linux2.l_i_uid_high 424#define i_gid_high osd2.linux2.l_i_gid_high 425#define i_reserved2 osd2.linux2.l_i_reserved2 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#else 429#if defined(__GNU__) 430 431#define i_translator osd1.hurd1.h_i_translator 432#define i_frag osd2.hurd2.h_i_frag; 433#define i_fsize osd2.hurd2.h_i_fsize; 434#define i_uid_high osd2.hurd2.h_i_uid_high 435#define i_gid_high osd2.hurd2.h_i_gid_high 436#define i_author osd2.hurd2.h_i_author 437#define inode_uid(inode) ((inode).i_uid | (inode).i_uid_high << 16) 438#define inode_gid(inode) ((inode).i_gid | (inode).i_gid_high << 16) 439 440#else 441#if defined(__masix__) 442 443#define i_reserved1 osd1.masix1.m_i_reserved1 444#define i_frag osd2.masix2.m_i_frag 445#define i_fsize osd2.masix2.m_i_fsize 446#define i_reserved2 osd2.masix2.m_i_reserved2 447#define inode_uid(inode) ((inode).i_uid) 448#define inode_gid(inode) ((inode).i_gid) 449 450#endif /* __masix__ */ 451#endif /* __GNU__ */ 452#endif /* defined(__KERNEL__) || defined(__linux__) */ 453 454/* 455 * File system states 456 */ 457#define EXT2_VALID_FS 0x0001 /* Unmounted cleanly */ 458#define EXT2_ERROR_FS 0x0002 /* Errors detected */ 459 460/* 461 * Misc. filesystem flags 462 */ 463#define EXT2_FLAGS_SIGNED_HASH 0x0001 /* Signed dirhash in use */ 464#define EXT2_FLAGS_UNSIGNED_HASH 0x0002 /* Unsigned dirhash in use */ 465 466/* 467 * Mount flags 468 */ 469#define EXT2_MOUNT_CHECK 0x0001 /* Do mount-time checks */ 470#define EXT2_MOUNT_GRPID 0x0004 /* Create files with directory's group */ 471#define EXT2_MOUNT_DEBUG 0x0008 /* Some debugging messages */ 472#define EXT2_MOUNT_ERRORS_CONT 0x0010 /* Continue on errors */ 473#define EXT2_MOUNT_ERRORS_RO 0x0020 /* Remount fs ro on errors */ 474#define EXT2_MOUNT_ERRORS_PANIC 0x0040 /* Panic on errors */ 475#define EXT2_MOUNT_MINIX_DF 0x0080 /* Mimics the Minix statfs */ 476#define EXT2_MOUNT_NO_UID32 0x0200 /* Disable 32-bit UIDs */ 477 478#define clear_opt(o, opt) o &= ~EXT2_MOUNT_##opt 479#define set_opt(o, opt) o |= EXT2_MOUNT_##opt 480#define test_opt(sb, opt) (EXT2_SB(sb)->s_mount_opt & \ 481 EXT2_MOUNT_##opt) 482/* 483 * Maximal mount counts between two filesystem checks 484 */ 485#define EXT2_DFL_MAX_MNT_COUNT 20 /* Allow 20 mounts */ 486#define EXT2_DFL_CHECKINTERVAL 0 /* Don't use interval check */ 487 488/* 489 * Behaviour when detecting errors 490 */ 491#define EXT2_ERRORS_CONTINUE 1 /* Continue execution */ 492#define EXT2_ERRORS_RO 2 /* Remount fs read-only */ 493#define EXT2_ERRORS_PANIC 3 /* Panic */ 494#define EXT2_ERRORS_DEFAULT EXT2_ERRORS_CONTINUE 495 496/* 497 * Structure of the super block 498 */ 499struct ext2_super_block { 500 __u32 s_inodes_count; /* Inodes count */ 501 __u32 s_blocks_count; /* Blocks count */ 502 __u32 s_r_blocks_count; /* Reserved blocks count */ 503 __u32 s_free_blocks_count; /* Free blocks count */ 504 __u32 s_free_inodes_count; /* Free inodes count */ 505 __u32 s_first_data_block; /* First Data Block */ 506 __u32 s_log_block_size; /* Block size */ 507 __s32 s_log_frag_size; /* Fragment size */ 508 __u32 s_blocks_per_group; /* # Blocks per group */ 509 __u32 s_frags_per_group; /* # Fragments per group */ 510 __u32 s_inodes_per_group; /* # Inodes per group */ 511 __u32 s_mtime; /* Mount time */ 512 __u32 s_wtime; /* Write time */ 513 __u16 s_mnt_count; /* Mount count */ 514 __s16 s_max_mnt_count; /* Maximal mount count */ 515 __u16 s_magic; /* Magic signature */ 516 __u16 s_state; /* File system state */ 517 __u16 s_errors; /* Behaviour when detecting errors */ 518 __u16 s_minor_rev_level; /* minor revision level */ 519 __u32 s_lastcheck; /* time of last check */ 520 __u32 s_checkinterval; /* max. time between checks */ 521 __u32 s_creator_os; /* OS */ 522 __u32 s_rev_level; /* Revision level */ 523 __u16 s_def_resuid; /* Default uid for reserved blocks */ 524 __u16 s_def_resgid; /* Default gid for reserved blocks */ 525 /* 526 * These fields are for EXT2_DYNAMIC_REV superblocks only. 527 * 528 * Note: the difference between the compatible feature set and 529 * the incompatible feature set is that if there is a bit set 530 * in the incompatible feature set that the kernel doesn't 531 * know about, it should refuse to mount the filesystem. 532 * 533 * e2fsck's requirements are more strict; if it doesn't know 534 * about a feature in either the compatible or incompatible 535 * feature set, it must abort and not try to meddle with 536 * things it doesn't understand... 537 */ 538 __u32 s_first_ino; /* First non-reserved inode */ 539 __u16 s_inode_size; /* size of inode structure */ 540 __u16 s_block_group_nr; /* block group # of this superblock */ 541 __u32 s_feature_compat; /* compatible feature set */ 542 __u32 s_feature_incompat; /* incompatible feature set */ 543 __u32 s_feature_ro_compat; /* readonly-compatible feature set */ 544 __u8 s_uuid[16]; /* 128-bit uuid for volume */ 545 char s_volume_name[16]; /* volume name */ 546 char s_last_mounted[64]; /* directory where last mounted */ 547 __u32 s_algorithm_usage_bitmap; /* For compression */ 548 /* 549 * Performance hints. Directory preallocation should only 550 * happen if the EXT2_FEATURE_COMPAT_DIR_PREALLOC flag is on. 551 */ 552 __u8 s_prealloc_blocks; /* Nr of blocks to try to preallocate*/ 553 __u8 s_prealloc_dir_blocks; /* Nr to preallocate for dirs */ 554 __u16 s_reserved_gdt_blocks; /* Per group table for online growth */ 555 /* 556 * Journaling support valid if EXT2_FEATURE_COMPAT_HAS_JOURNAL set. 557 */ 558 __u8 s_journal_uuid[16]; /* uuid of journal superblock */ 559 __u32 s_journal_inum; /* inode number of journal file */ 560 __u32 s_journal_dev; /* device number of journal file */ 561 __u32 s_last_orphan; /* start of list of inodes to delete */ 562 __u32 s_hash_seed[4]; /* HTREE hash seed */ 563 __u8 s_def_hash_version; /* Default hash version to use */ 564 __u8 s_jnl_backup_type; /* Default type of journal backup */ 565 __u16 s_desc_size; /* Group desc. size: INCOMPAT_64BIT */ 566 __u32 s_default_mount_opts; 567 __u32 s_first_meta_bg; /* First metablock group */ 568 __u32 s_mkfs_time; /* When the filesystem was created */ 569 __u32 s_jnl_blocks[17]; /* Backup of the journal inode */ 570 __u32 s_blocks_count_hi; /* Blocks count high 32bits */ 571 __u32 s_r_blocks_count_hi; /* Reserved blocks count high 32 bits*/ 572 __u32 s_free_blocks_hi; /* Free blocks count */ 573 __u16 s_min_extra_isize; /* All inodes have at least # bytes */ 574 __u16 s_want_extra_isize; /* New inodes should reserve # bytes */ 575 __u32 s_flags; /* Miscellaneous flags */ 576 __u16 s_raid_stride; /* RAID stride */ 577 __u16 s_mmp_interval; /* # seconds to wait in MMP checking */ 578 __u64 s_mmp_block; /* Block for multi-mount protection */ 579 __u32 s_reserved[164]; /* Padding to the end of the block */ 580}; 581 582/* 583 * Codes for operating systems 584 */ 585#define EXT2_OS_LINUX 0 586#define EXT2_OS_HURD 1 587#define EXT2_OS_MASIX 2 588#define EXT2_OS_FREEBSD 3 589#define EXT2_OS_LITES 4 590 591/* 592 * Revision levels 593 */ 594#define EXT2_GOOD_OLD_REV 0 /* The good old (original) format */ 595#define EXT2_DYNAMIC_REV 1 /* V2 format w/ dynamic inode sizes */ 596 597#define EXT2_CURRENT_REV EXT2_GOOD_OLD_REV 598#define EXT2_MAX_SUPP_REV EXT2_DYNAMIC_REV 599 600#define EXT2_GOOD_OLD_INODE_SIZE 128 601 602/* 603 * Journal inode backup types 604 */ 605#define EXT3_JNL_BACKUP_BLOCKS 1 606 607/* 608 * Feature set definitions 609 */ 610 611#define EXT2_HAS_COMPAT_FEATURE(sb,mask) \ 612 ( EXT2_SB(sb)->s_feature_compat & (mask) ) 613#define EXT2_HAS_RO_COMPAT_FEATURE(sb,mask) \ 614 ( EXT2_SB(sb)->s_feature_ro_compat & (mask) ) 615#define EXT2_HAS_INCOMPAT_FEATURE(sb,mask) \ 616 ( EXT2_SB(sb)->s_feature_incompat & (mask) ) 617 618#define EXT2_FEATURE_COMPAT_DIR_PREALLOC 0x0001 619#define EXT2_FEATURE_COMPAT_IMAGIC_INODES 0x0002 620#define EXT3_FEATURE_COMPAT_HAS_JOURNAL 0x0004 621#define EXT2_FEATURE_COMPAT_EXT_ATTR 0x0008 622#define EXT2_FEATURE_COMPAT_RESIZE_INODE 0x0010 623#define EXT2_FEATURE_COMPAT_DIR_INDEX 0x0020 624#define EXT2_FEATURE_COMPAT_LAZY_BG 0x0040 625 626#define EXT2_FEATURE_RO_COMPAT_SPARSE_SUPER 0x0001 627#define EXT2_FEATURE_RO_COMPAT_LARGE_FILE 0x0002 628/* #define EXT2_FEATURE_RO_COMPAT_BTREE_DIR 0x0004 not used */ 629#define EXT4_FEATURE_RO_COMPAT_HUGE_FILE 0x0008 630#define EXT4_FEATURE_RO_COMPAT_GDT_CSUM 0x0010 631#define EXT4_FEATURE_RO_COMPAT_DIR_NLINK 0x0020 632#define EXT4_FEATURE_RO_COMPAT_EXTRA_ISIZE 0x0040 633 634#define EXT2_FEATURE_INCOMPAT_COMPRESSION 0x0001 635#define EXT2_FEATURE_INCOMPAT_FILETYPE 0x0002 636#define EXT3_FEATURE_INCOMPAT_RECOVER 0x0004 /* Needs recovery */ 637#define EXT3_FEATURE_INCOMPAT_JOURNAL_DEV 0x0008 /* Journal device */ 638#define EXT2_FEATURE_INCOMPAT_META_BG 0x0010 639#define EXT3_FEATURE_INCOMPAT_EXTENTS 0x0040 640#define EXT4_FEATURE_INCOMPAT_64BIT 0x0080 641#define EXT4_FEATURE_INCOMPAT_MMP 0x0100 642 643 644#define EXT2_FEATURE_COMPAT_SUPP 0 645#define EXT2_FEATURE_INCOMPAT_SUPP (EXT2_FEATURE_INCOMPAT_FILETYPE) 646#define EXT2_FEATURE_RO_COMPAT_SUPP (EXT2_FEATURE_RO_COMPAT_SPARSE_SUPER| \ 647 EXT2_FEATURE_RO_COMPAT_LARGE_FILE| \ 648 EXT2_FEATURE_RO_COMPAT_BTREE_DIR) 649 650/* 651 * Default values for user and/or group using reserved blocks 652 */ 653#define EXT2_DEF_RESUID 0 654#define EXT2_DEF_RESGID 0 655 656/* 657 * Default mount options 658 */ 659#define EXT2_DEFM_DEBUG 0x0001 660#define EXT2_DEFM_BSDGROUPS 0x0002 661#define EXT2_DEFM_XATTR_USER 0x0004 662#define EXT2_DEFM_ACL 0x0008 663#define EXT2_DEFM_UID16 0x0010 664#define EXT3_DEFM_JMODE 0x0060 665#define EXT3_DEFM_JMODE_DATA 0x0020 666#define EXT3_DEFM_JMODE_ORDERED 0x0040 667#define EXT3_DEFM_JMODE_WBACK 0x0060 668 669/* 670 * Structure of a directory entry 671 */ 672#define EXT2_NAME_LEN 255 673 674struct ext2_dir_entry { 675 __u32 inode; /* Inode number */ 676 __u16 rec_len; /* Directory entry length */ 677 __u16 name_len; /* Name length */ 678 char name[EXT2_NAME_LEN]; /* File name */ 679}; 680 681/* 682 * The new version of the directory entry. Since EXT2 structures are 683 * stored in intel byte order, and the name_len field could never be 684 * bigger than 255 chars, it's safe to reclaim the extra byte for the 685 * file_type field. 686 */ 687struct ext2_dir_entry_2 { 688 __u32 inode; /* Inode number */ 689 __u16 rec_len; /* Directory entry length */ 690 __u8 name_len; /* Name length */ 691 __u8 file_type; 692 char name[EXT2_NAME_LEN]; /* File name */ 693}; 694 695/* 696 * Ext2 directory file types. Only the low 3 bits are used. The 697 * other bits are reserved for now. 698 */ 699#define EXT2_FT_UNKNOWN 0 700#define EXT2_FT_REG_FILE 1 701#define EXT2_FT_DIR 2 702#define EXT2_FT_CHRDEV 3 703#define EXT2_FT_BLKDEV 4 704#define EXT2_FT_FIFO 5 705#define EXT2_FT_SOCK 6 706#define EXT2_FT_SYMLINK 7 707 708#define EXT2_FT_MAX 8 709 710/* 711 * EXT2_DIR_PAD defines the directory entries boundaries 712 * 713 * NOTE: It must be a multiple of 4 714 */ 715#define EXT2_DIR_PAD 4 716#define EXT2_DIR_ROUND (EXT2_DIR_PAD - 1) 717#define EXT2_DIR_REC_LEN(name_len) (((name_len) + 8 + EXT2_DIR_ROUND) & \ 718 ~EXT2_DIR_ROUND) 719 720/* 721 * This structure will be used for multiple mount protection. It will be 722 * written into the block number saved in the s_mmp_block field in the 723 * superblock. 724 */ 725#define EXT2_MMP_MAGIC 0x004D4D50 /* ASCII for MMP */ 726#define EXT2_MMP_CLEAN 0xFF4D4D50 /* Value of mmp_seq for clean unmount */ 727#define EXT2_MMP_FSCK_ON 0xE24D4D50 /* Value of mmp_seq when being fscked */ 728 729struct mmp_struct { 730 __u32 mmp_magic; 731 __u32 mmp_seq; 732 __u64 mmp_time; 733 char mmp_nodename[64]; 734 char mmp_bdevname[32]; 735 __u16 mmp_interval; 736 __u16 mmp_pad1; 737 __u32 mmp_pad2; 738}; 739 740/* 741 * Interval in number of seconds to update the MMP sequence number. 742 */ 743#define EXT2_MMP_DEF_INTERVAL 5 744 745#endif /* _LINUX_EXT2_FS_H */ 746