ext2_fs.h revision 428f6b32a9029e1f0bc2559233954955a6aae64c
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#ifdef __GNU__ /* Needed for the Hurd */ 295#define _IOT_ext2_new_group_input _IOT (_IOTS(__u32), 5, _IOTS(__u16), 2, 0, 0) 296#endif 297 298#define EXT2_IOC_GETFLAGS _IOR('f', 1, long) 299#define EXT2_IOC_SETFLAGS _IOW('f', 2, long) 300#define EXT2_IOC_GETVERSION _IOR('v', 1, long) 301#define EXT2_IOC_SETVERSION _IOW('v', 2, long) 302#define EXT2_IOC_GETVERSION_NEW _IOR('f', 3, long) 303#define EXT2_IOC_SETVERSION_NEW _IOW('f', 4, long) 304#define EXT2_IOC_GROUP_EXTEND _IOW('f', 7, unsigned long) 305#define EXT2_IOC_GROUP_ADD _IOW('f', 8,struct ext2_new_group_input) 306 307/* 308 * Structure of an inode on the disk 309 */ 310struct ext2_inode { 311 __u16 i_mode; /* File mode */ 312 __u16 i_uid; /* Low 16 bits of Owner Uid */ 313 __u32 i_size; /* Size in bytes */ 314 __u32 i_atime; /* Access time */ 315 __u32 i_ctime; /* Inode change time */ 316 __u32 i_mtime; /* Modification time */ 317 __u32 i_dtime; /* Deletion Time */ 318 __u16 i_gid; /* Low 16 bits of Group Id */ 319 __u16 i_links_count; /* Links count */ 320 __u32 i_blocks; /* Blocks count */ 321 __u32 i_flags; /* File flags */ 322 union { 323 struct { 324 __u32 l_i_version; /* was l_i_reserved1 */ 325 } linux1; 326 struct { 327 __u32 h_i_translator; 328 } hurd1; 329 } osd1; /* OS dependent 1 */ 330 __u32 i_block[EXT2_N_BLOCKS];/* Pointers to blocks */ 331 __u32 i_generation; /* File version (for NFS) */ 332 __u32 i_file_acl; /* File ACL */ 333 __u32 i_dir_acl; /* Directory ACL */ 334 __u32 i_faddr; /* Fragment address */ 335 union { 336 struct { 337 __u16 l_i_blocks_hi; 338 __u16 i_pad1; 339 __u16 l_i_uid_high; /* these 2 fields */ 340 __u16 l_i_gid_high; /* were reserved2[0] */ 341 __u32 l_i_reserved2; 342 } linux2; 343 struct { 344 __u8 h_i_frag; /* Fragment number */ 345 __u8 h_i_fsize; /* Fragment size */ 346 __u16 h_i_mode_high; 347 __u16 h_i_uid_high; 348 __u16 h_i_gid_high; 349 __u32 h_i_author; 350 } hurd2; 351 } osd2; /* OS dependent 2 */ 352}; 353 354/* 355 * Permanent part of an large inode on the disk 356 */ 357struct ext2_inode_large { 358 __u16 i_mode; /* File mode */ 359 __u16 i_uid; /* Low 16 bits of Owner Uid */ 360 __u32 i_size; /* Size in bytes */ 361 __u32 i_atime; /* Access time */ 362 __u32 i_ctime; /* Inode Change time */ 363 __u32 i_mtime; /* Modification time */ 364 __u32 i_dtime; /* Deletion Time */ 365 __u16 i_gid; /* Low 16 bits of Group Id */ 366 __u16 i_links_count; /* Links count */ 367 __u32 i_blocks; /* Blocks count */ 368 __u32 i_flags; /* File flags */ 369 union { 370 struct { 371 __u32 l_i_version; /* was l_i_reserved1 */ 372 } linux1; 373 struct { 374 __u32 h_i_translator; 375 } hurd1; 376 } osd1; /* OS dependent 1 */ 377 __u32 i_block[EXT2_N_BLOCKS];/* Pointers to blocks */ 378 __u32 i_generation; /* File version (for NFS) */ 379 __u32 i_file_acl; /* File ACL */ 380 __u32 i_dir_acl; /* Directory ACL */ 381 __u32 i_faddr; /* Fragment address */ 382 union { 383 struct { 384 __u16 l_i_blocks_hi; 385 __u16 i_pad1; 386 __u16 l_i_uid_high; /* these 2 fields */ 387 __u16 l_i_gid_high; /* were reserved2[0] */ 388 __u32 l_i_reserved2; 389 } linux2; 390 struct { 391 __u8 h_i_frag; /* Fragment number */ 392 __u8 h_i_fsize; /* Fragment size */ 393 __u16 h_i_mode_high; 394 __u16 h_i_uid_high; 395 __u16 h_i_gid_high; 396 __u32 h_i_author; 397 } hurd2; 398 } osd2; /* OS dependent 2 */ 399 __u16 i_extra_isize; 400 __u16 i_pad1; 401 __u32 i_ctime_extra; /* extra Change time (nsec << 2 | epoch) */ 402 __u32 i_mtime_extra; /* extra Modification time (nsec << 2 | epoch) */ 403 __u32 i_atime_extra; /* extra Access time (nsec << 2 | epoch) */ 404 __u32 i_crtime; /* File creation time */ 405 __u32 i_crtime_extra; /* extra File creation time (nsec << 2 | epoch)*/ 406}; 407 408#define i_size_high i_dir_acl 409 410#if defined(__KERNEL__) || defined(__linux__) 411#define i_reserved1 osd1.linux1.l_i_reserved1 412#define i_frag osd2.linux2.l_i_frag 413#define i_fsize osd2.linux2.l_i_fsize 414#define i_uid_low i_uid 415#define i_gid_low i_gid 416#define i_uid_high osd2.linux2.l_i_uid_high 417#define i_gid_high osd2.linux2.l_i_gid_high 418#define i_reserved2 osd2.linux2.l_i_reserved2 419#else 420#if defined(__GNU__) 421 422#define i_translator osd1.hurd1.h_i_translator 423#define i_frag osd2.hurd2.h_i_frag; 424#define i_fsize osd2.hurd2.h_i_fsize; 425#define i_uid_high osd2.hurd2.h_i_uid_high 426#define i_gid_high osd2.hurd2.h_i_gid_high 427#define i_author osd2.hurd2.h_i_author 428 429#endif /* __GNU__ */ 430#endif /* defined(__KERNEL__) || defined(__linux__) */ 431 432#define inode_uid(inode) ((inode).i_uid | (inode).osd2.linux2.l_i_uid_high << 16) 433#define inode_gid(inode) ((inode).i_gid | (inode).osd2.linux2.l_i_gid_high << 16) 434#define ext2fs_set_i_uid_high(inode,x) ((inode).osd2.linux2.l_i_uid_high = (x)) 435#define ext2fs_set_i_gid_high(inode,x) ((inode).osd2.linux2.l_i_gid_high = (x)) 436 437/* 438 * File system states 439 */ 440#define EXT2_VALID_FS 0x0001 /* Unmounted cleanly */ 441#define EXT2_ERROR_FS 0x0002 /* Errors detected */ 442#define EXT4_ORPHAN_FS 0x0004 /* Orphans being recovered */ 443 444/* 445 * Misc. filesystem flags 446 */ 447#define EXT2_FLAGS_SIGNED_HASH 0x0001 /* Signed dirhash in use */ 448#define EXT2_FLAGS_UNSIGNED_HASH 0x0002 /* Unsigned dirhash in use */ 449#define EXT2_FLAGS_TEST_FILESYS 0x0004 /* OK for use on development code */ 450 451/* 452 * Mount flags 453 */ 454#define EXT2_MOUNT_CHECK 0x0001 /* Do mount-time checks */ 455#define EXT2_MOUNT_GRPID 0x0004 /* Create files with directory's group */ 456#define EXT2_MOUNT_DEBUG 0x0008 /* Some debugging messages */ 457#define EXT2_MOUNT_ERRORS_CONT 0x0010 /* Continue on errors */ 458#define EXT2_MOUNT_ERRORS_RO 0x0020 /* Remount fs ro on errors */ 459#define EXT2_MOUNT_ERRORS_PANIC 0x0040 /* Panic on errors */ 460#define EXT2_MOUNT_MINIX_DF 0x0080 /* Mimics the Minix statfs */ 461#define EXT2_MOUNT_NO_UID32 0x0200 /* Disable 32-bit UIDs */ 462 463#define clear_opt(o, opt) o &= ~EXT2_MOUNT_##opt 464#define set_opt(o, opt) o |= EXT2_MOUNT_##opt 465#define test_opt(sb, opt) (EXT2_SB(sb)->s_mount_opt & \ 466 EXT2_MOUNT_##opt) 467/* 468 * Maximal mount counts between two filesystem checks 469 */ 470#define EXT2_DFL_MAX_MNT_COUNT 20 /* Allow 20 mounts */ 471#define EXT2_DFL_CHECKINTERVAL 0 /* Don't use interval check */ 472 473/* 474 * Behaviour when detecting errors 475 */ 476#define EXT2_ERRORS_CONTINUE 1 /* Continue execution */ 477#define EXT2_ERRORS_RO 2 /* Remount fs read-only */ 478#define EXT2_ERRORS_PANIC 3 /* Panic */ 479#define EXT2_ERRORS_DEFAULT EXT2_ERRORS_CONTINUE 480 481/* 482 * Structure of the super block 483 */ 484struct ext2_super_block { 485 __u32 s_inodes_count; /* Inodes count */ 486 __u32 s_blocks_count; /* Blocks count */ 487 __u32 s_r_blocks_count; /* Reserved blocks count */ 488 __u32 s_free_blocks_count; /* Free blocks count */ 489 __u32 s_free_inodes_count; /* Free inodes count */ 490 __u32 s_first_data_block; /* First Data Block */ 491 __u32 s_log_block_size; /* Block size */ 492 __s32 s_log_frag_size; /* Fragment size */ 493 __u32 s_blocks_per_group; /* # Blocks per group */ 494 __u32 s_frags_per_group; /* # Fragments per group */ 495 __u32 s_inodes_per_group; /* # Inodes per group */ 496 __u32 s_mtime; /* Mount time */ 497 __u32 s_wtime; /* Write time */ 498 __u16 s_mnt_count; /* Mount count */ 499 __s16 s_max_mnt_count; /* Maximal mount count */ 500 __u16 s_magic; /* Magic signature */ 501 __u16 s_state; /* File system state */ 502 __u16 s_errors; /* Behaviour when detecting errors */ 503 __u16 s_minor_rev_level; /* minor revision level */ 504 __u32 s_lastcheck; /* time of last check */ 505 __u32 s_checkinterval; /* max. time between checks */ 506 __u32 s_creator_os; /* OS */ 507 __u32 s_rev_level; /* Revision level */ 508 __u16 s_def_resuid; /* Default uid for reserved blocks */ 509 __u16 s_def_resgid; /* Default gid for reserved blocks */ 510 /* 511 * These fields are for EXT2_DYNAMIC_REV superblocks only. 512 * 513 * Note: the difference between the compatible feature set and 514 * the incompatible feature set is that if there is a bit set 515 * in the incompatible feature set that the kernel doesn't 516 * know about, it should refuse to mount the filesystem. 517 * 518 * e2fsck's requirements are more strict; if it doesn't know 519 * about a feature in either the compatible or incompatible 520 * feature set, it must abort and not try to meddle with 521 * things it doesn't understand... 522 */ 523 __u32 s_first_ino; /* First non-reserved inode */ 524 __u16 s_inode_size; /* size of inode structure */ 525 __u16 s_block_group_nr; /* block group # of this superblock */ 526 __u32 s_feature_compat; /* compatible feature set */ 527 __u32 s_feature_incompat; /* incompatible feature set */ 528 __u32 s_feature_ro_compat; /* readonly-compatible feature set */ 529 __u8 s_uuid[16]; /* 128-bit uuid for volume */ 530 char s_volume_name[16]; /* volume name */ 531 char s_last_mounted[64]; /* directory where last mounted */ 532 __u32 s_algorithm_usage_bitmap; /* For compression */ 533 /* 534 * Performance hints. Directory preallocation should only 535 * happen if the EXT2_FEATURE_COMPAT_DIR_PREALLOC flag is on. 536 */ 537 __u8 s_prealloc_blocks; /* Nr of blocks to try to preallocate*/ 538 __u8 s_prealloc_dir_blocks; /* Nr to preallocate for dirs */ 539 __u16 s_reserved_gdt_blocks; /* Per group table for online growth */ 540 /* 541 * Journaling support valid if EXT2_FEATURE_COMPAT_HAS_JOURNAL set. 542 */ 543 __u8 s_journal_uuid[16]; /* uuid of journal superblock */ 544 __u32 s_journal_inum; /* inode number of journal file */ 545 __u32 s_journal_dev; /* device number of journal file */ 546 __u32 s_last_orphan; /* start of list of inodes to delete */ 547 __u32 s_hash_seed[4]; /* HTREE hash seed */ 548 __u8 s_def_hash_version; /* Default hash version to use */ 549 __u8 s_jnl_backup_type; /* Default type of journal backup */ 550 __u16 s_desc_size; /* Group desc. size: INCOMPAT_64BIT */ 551 __u32 s_default_mount_opts; 552 __u32 s_first_meta_bg; /* First metablock group */ 553 __u32 s_mkfs_time; /* When the filesystem was created */ 554 __u32 s_jnl_blocks[17]; /* Backup of the journal inode */ 555 __u32 s_blocks_count_hi; /* Blocks count high 32bits */ 556 __u32 s_r_blocks_count_hi; /* Reserved blocks count high 32 bits*/ 557 __u32 s_free_blocks_hi; /* Free blocks count */ 558 __u16 s_min_extra_isize; /* All inodes have at least # bytes */ 559 __u16 s_want_extra_isize; /* New inodes should reserve # bytes */ 560 __u32 s_flags; /* Miscellaneous flags */ 561 __u16 s_raid_stride; /* RAID stride */ 562 __u16 s_mmp_interval; /* # seconds to wait in MMP checking */ 563 __u64 s_mmp_block; /* Block for multi-mount protection */ 564 __u32 s_raid_stripe_width; /* blocks on all data disks (N*stride)*/ 565 __u32 s_reserved[163]; /* Padding to the end of the block */ 566}; 567 568/* 569 * Codes for operating systems 570 */ 571#define EXT2_OS_LINUX 0 572#define EXT2_OS_HURD 1 573#define EXT2_OBSO_OS_MASIX 2 574#define EXT2_OS_FREEBSD 3 575#define EXT2_OS_LITES 4 576 577/* 578 * Revision levels 579 */ 580#define EXT2_GOOD_OLD_REV 0 /* The good old (original) format */ 581#define EXT2_DYNAMIC_REV 1 /* V2 format w/ dynamic inode sizes */ 582 583#define EXT2_CURRENT_REV EXT2_GOOD_OLD_REV 584#define EXT2_MAX_SUPP_REV EXT2_DYNAMIC_REV 585 586#define EXT2_GOOD_OLD_INODE_SIZE 128 587 588/* 589 * Journal inode backup types 590 */ 591#define EXT3_JNL_BACKUP_BLOCKS 1 592 593/* 594 * Feature set definitions 595 */ 596 597#define EXT2_HAS_COMPAT_FEATURE(sb,mask) \ 598 ( EXT2_SB(sb)->s_feature_compat & (mask) ) 599#define EXT2_HAS_RO_COMPAT_FEATURE(sb,mask) \ 600 ( EXT2_SB(sb)->s_feature_ro_compat & (mask) ) 601#define EXT2_HAS_INCOMPAT_FEATURE(sb,mask) \ 602 ( EXT2_SB(sb)->s_feature_incompat & (mask) ) 603 604#define EXT2_FEATURE_COMPAT_DIR_PREALLOC 0x0001 605#define EXT2_FEATURE_COMPAT_IMAGIC_INODES 0x0002 606#define EXT3_FEATURE_COMPAT_HAS_JOURNAL 0x0004 607#define EXT2_FEATURE_COMPAT_EXT_ATTR 0x0008 608#define EXT2_FEATURE_COMPAT_RESIZE_INODE 0x0010 609#define EXT2_FEATURE_COMPAT_DIR_INDEX 0x0020 610#define EXT2_FEATURE_COMPAT_LAZY_BG 0x0040 611 612#define EXT2_FEATURE_RO_COMPAT_SPARSE_SUPER 0x0001 613#define EXT2_FEATURE_RO_COMPAT_LARGE_FILE 0x0002 614/* #define EXT2_FEATURE_RO_COMPAT_BTREE_DIR 0x0004 not used */ 615#define EXT4_FEATURE_RO_COMPAT_HUGE_FILE 0x0008 616#define EXT4_FEATURE_RO_COMPAT_GDT_CSUM 0x0010 617#define EXT4_FEATURE_RO_COMPAT_DIR_NLINK 0x0020 618#define EXT4_FEATURE_RO_COMPAT_EXTRA_ISIZE 0x0040 619 620#define EXT2_FEATURE_INCOMPAT_COMPRESSION 0x0001 621#define EXT2_FEATURE_INCOMPAT_FILETYPE 0x0002 622#define EXT3_FEATURE_INCOMPAT_RECOVER 0x0004 /* Needs recovery */ 623#define EXT3_FEATURE_INCOMPAT_JOURNAL_DEV 0x0008 /* Journal device */ 624#define EXT2_FEATURE_INCOMPAT_META_BG 0x0010 625#define EXT3_FEATURE_INCOMPAT_EXTENTS 0x0040 626#define EXT4_FEATURE_INCOMPAT_64BIT 0x0080 627#define EXT4_FEATURE_INCOMPAT_MMP 0x0100 628#define EXT4_FEATURE_INCOMPAT_FLEX_BG 0x0200 629 630 631#define EXT2_FEATURE_COMPAT_SUPP 0 632#define EXT2_FEATURE_INCOMPAT_SUPP (EXT2_FEATURE_INCOMPAT_FILETYPE) 633#define EXT2_FEATURE_RO_COMPAT_SUPP (EXT2_FEATURE_RO_COMPAT_SPARSE_SUPER| \ 634 EXT2_FEATURE_RO_COMPAT_LARGE_FILE| \ 635 EXT2_FEATURE_RO_COMPAT_BTREE_DIR) 636 637/* 638 * Default values for user and/or group using reserved blocks 639 */ 640#define EXT2_DEF_RESUID 0 641#define EXT2_DEF_RESGID 0 642 643/* 644 * Default mount options 645 */ 646#define EXT2_DEFM_DEBUG 0x0001 647#define EXT2_DEFM_BSDGROUPS 0x0002 648#define EXT2_DEFM_XATTR_USER 0x0004 649#define EXT2_DEFM_ACL 0x0008 650#define EXT2_DEFM_UID16 0x0010 651#define EXT3_DEFM_JMODE 0x0060 652#define EXT3_DEFM_JMODE_DATA 0x0020 653#define EXT3_DEFM_JMODE_ORDERED 0x0040 654#define EXT3_DEFM_JMODE_WBACK 0x0060 655 656/* 657 * Structure of a directory entry 658 */ 659#define EXT2_NAME_LEN 255 660 661struct ext2_dir_entry { 662 __u32 inode; /* Inode number */ 663 __u16 rec_len; /* Directory entry length */ 664 __u16 name_len; /* Name length */ 665 char name[EXT2_NAME_LEN]; /* File name */ 666}; 667 668/* 669 * The new version of the directory entry. Since EXT2 structures are 670 * stored in intel byte order, and the name_len field could never be 671 * bigger than 255 chars, it's safe to reclaim the extra byte for the 672 * file_type field. 673 */ 674struct ext2_dir_entry_2 { 675 __u32 inode; /* Inode number */ 676 __u16 rec_len; /* Directory entry length */ 677 __u8 name_len; /* Name length */ 678 __u8 file_type; 679 char name[EXT2_NAME_LEN]; /* File name */ 680}; 681 682/* 683 * Ext2 directory file types. Only the low 3 bits are used. The 684 * other bits are reserved for now. 685 */ 686#define EXT2_FT_UNKNOWN 0 687#define EXT2_FT_REG_FILE 1 688#define EXT2_FT_DIR 2 689#define EXT2_FT_CHRDEV 3 690#define EXT2_FT_BLKDEV 4 691#define EXT2_FT_FIFO 5 692#define EXT2_FT_SOCK 6 693#define EXT2_FT_SYMLINK 7 694 695#define EXT2_FT_MAX 8 696 697/* 698 * EXT2_DIR_PAD defines the directory entries boundaries 699 * 700 * NOTE: It must be a multiple of 4 701 */ 702#define EXT2_DIR_PAD 4 703#define EXT2_DIR_ROUND (EXT2_DIR_PAD - 1) 704#define EXT2_DIR_REC_LEN(name_len) (((name_len) + 8 + EXT2_DIR_ROUND) & \ 705 ~EXT2_DIR_ROUND) 706 707/* 708 * This structure will be used for multiple mount protection. It will be 709 * written into the block number saved in the s_mmp_block field in the 710 * superblock. 711 */ 712#define EXT2_MMP_MAGIC 0x004D4D50 /* ASCII for MMP */ 713#define EXT2_MMP_CLEAN 0xFF4D4D50 /* Value of mmp_seq for clean unmount */ 714#define EXT2_MMP_FSCK_ON 0xE24D4D50 /* Value of mmp_seq when being fscked */ 715 716struct mmp_struct { 717 __u32 mmp_magic; 718 __u32 mmp_seq; 719 __u64 mmp_time; 720 char mmp_nodename[64]; 721 char mmp_bdevname[32]; 722 __u16 mmp_interval; 723 __u16 mmp_pad1; 724 __u32 mmp_pad2; 725}; 726 727/* 728 * Interval in number of seconds to update the MMP sequence number. 729 */ 730#define EXT2_MMP_DEF_INTERVAL 5 731 732#endif /* _LINUX_EXT2_FS_H */ 733