ext2_fs.h revision 412376efff3c0e0c2fea00666c2457e6f2ae1878
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 EXT4_USR_QUOTA_INO 3 /* User quota inode */ 48#define EXT4_GRP_QUOTA_INO 4 /* Group quota 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#define EXT2_EXCLUDE_INO 9 /* The "exclude" inode, for snapshots */ 54 55/* First non-reserved inode for old ext2 filesystems */ 56#define EXT2_GOOD_OLD_FIRST_INO 11 57 58/* 59 * The second extended file system magic number 60 */ 61#define EXT2_SUPER_MAGIC 0xEF53 62 63#ifdef __KERNEL__ 64#define EXT2_SB(sb) (&((sb)->u.ext2_sb)) 65#else 66/* Assume that user mode programs are passing in an ext2fs superblock, not 67 * a kernel struct super_block. This will allow us to call the feature-test 68 * macros from user land. */ 69#define EXT2_SB(sb) (sb) 70#endif 71 72/* 73 * Maximal count of links to a file 74 */ 75#define EXT2_LINK_MAX 65000 76 77/* 78 * Macro-instructions used to manage several block sizes 79 */ 80#define EXT2_MIN_BLOCK_LOG_SIZE 10 /* 1024 */ 81#define EXT2_MAX_BLOCK_LOG_SIZE 16 /* 65536 */ 82#define EXT2_MIN_BLOCK_SIZE (1 << EXT2_MIN_BLOCK_LOG_SIZE) 83#define EXT2_MAX_BLOCK_SIZE (1 << EXT2_MAX_BLOCK_LOG_SIZE) 84#ifdef __KERNEL__ 85#define EXT2_BLOCK_SIZE(s) ((s)->s_blocksize) 86#define EXT2_BLOCK_SIZE_BITS(s) ((s)->s_blocksize_bits) 87#define EXT2_ADDR_PER_BLOCK_BITS(s) (EXT2_SB(s)->addr_per_block_bits) 88#define EXT2_INODE_SIZE(s) (EXT2_SB(s)->s_inode_size) 89#define EXT2_FIRST_INO(s) (EXT2_SB(s)->s_first_ino) 90#else 91#define EXT2_BLOCK_SIZE(s) (EXT2_MIN_BLOCK_SIZE << (s)->s_log_block_size) 92#define EXT2_BLOCK_SIZE_BITS(s) ((s)->s_log_block_size + 10) 93#define EXT2_INODE_SIZE(s) (((s)->s_rev_level == EXT2_GOOD_OLD_REV) ? \ 94 EXT2_GOOD_OLD_INODE_SIZE : (s)->s_inode_size) 95#define EXT2_FIRST_INO(s) (((s)->s_rev_level == EXT2_GOOD_OLD_REV) ? \ 96 EXT2_GOOD_OLD_FIRST_INO : (s)->s_first_ino) 97#endif 98#define EXT2_ADDR_PER_BLOCK(s) (EXT2_BLOCK_SIZE(s) / sizeof(__u32)) 99 100/* 101 * Macro-instructions used to manage allocation clusters 102 */ 103#define EXT2_MIN_CLUSTER_LOG_SIZE EXT2_MIN_BLOCK_LOG_SIZE 104#define EXT2_MAX_CLUSTER_LOG_SIZE 29 /* 512MB */ 105#define EXT2_MIN_CLUSTER_SIZE EXT2_MIN_BLOCK_SIZE 106#define EXT2_MAX_CLUSTER_SIZE (1 << EXT2_MAX_CLUSTER_LOG_SIZE) 107#define EXT2_CLUSTER_SIZE(s) (EXT2_MIN_BLOCK_SIZE << \ 108 (s)->s_log_cluster_size) 109#define EXT2_CLUSTER_SIZE_BITS(s) ((s)->s_log_cluster_size + 10) 110 111/* 112 * ACL structures 113 */ 114struct ext2_acl_header /* Header of Access Control Lists */ 115{ 116 __u32 aclh_size; 117 __u32 aclh_file_count; 118 __u32 aclh_acle_count; 119 __u32 aclh_first_acle; 120}; 121 122struct ext2_acl_entry /* Access Control List Entry */ 123{ 124 __u32 acle_size; 125 __u16 acle_perms; /* Access permissions */ 126 __u16 acle_type; /* Type of entry */ 127 __u16 acle_tag; /* User or group identity */ 128 __u16 acle_pad1; 129 __u32 acle_next; /* Pointer on next entry for the */ 130 /* same inode or on next free entry */ 131}; 132 133/* 134 * Structure of a blocks group descriptor 135 */ 136struct ext2_group_desc 137{ 138 __u32 bg_block_bitmap; /* Blocks bitmap block */ 139 __u32 bg_inode_bitmap; /* Inodes bitmap block */ 140 __u32 bg_inode_table; /* Inodes table block */ 141 __u16 bg_free_blocks_count; /* Free blocks count */ 142 __u16 bg_free_inodes_count; /* Free inodes count */ 143 __u16 bg_used_dirs_count; /* Directories count */ 144 __u16 bg_flags; 145 __u32 bg_reserved[2]; 146 __u16 bg_itable_unused; /* Unused inodes count */ 147 __u16 bg_checksum; /* crc16(s_uuid+grouo_num+group_desc)*/ 148}; 149 150struct ext4_group_desc 151{ 152 __u32 bg_block_bitmap; /* Blocks bitmap block */ 153 __u32 bg_inode_bitmap; /* Inodes bitmap block */ 154 __u32 bg_inode_table; /* Inodes table block */ 155 __u16 bg_free_blocks_count; /* Free blocks count */ 156 __u16 bg_free_inodes_count; /* Free inodes count */ 157 __u16 bg_used_dirs_count; /* Directories count */ 158 __u16 bg_flags; 159 __u32 bg_reserved[2]; 160 __u16 bg_itable_unused; /* Unused inodes count */ 161 __u16 bg_checksum; /* crc16(s_uuid+grouo_num+group_desc)*/ 162 __u32 bg_block_bitmap_hi; /* Blocks bitmap block MSB */ 163 __u32 bg_inode_bitmap_hi; /* Inodes bitmap block MSB */ 164 __u32 bg_inode_table_hi; /* Inodes table block MSB */ 165 __u16 bg_free_blocks_count_hi;/* Free blocks count MSB */ 166 __u16 bg_free_inodes_count_hi;/* Free inodes count MSB */ 167 __u16 bg_used_dirs_count_hi; /* Directories count MSB */ 168 __u16 bg_pad; 169 __u32 bg_reserved2[3]; 170}; 171 172#define EXT2_BG_INODE_UNINIT 0x0001 /* Inode table/bitmap not initialized */ 173#define EXT2_BG_BLOCK_UNINIT 0x0002 /* Block bitmap not initialized */ 174#define EXT2_BG_INODE_ZEROED 0x0004 /* On-disk itable initialized to zero */ 175 176/* 177 * Data structures used by the directory indexing feature 178 * 179 * Note: all of the multibyte integer fields are little endian. 180 */ 181 182/* 183 * Note: dx_root_info is laid out so that if it should somehow get 184 * overlaid by a dirent the two low bits of the hash version will be 185 * zero. Therefore, the hash version mod 4 should never be 0. 186 * Sincerely, the paranoia department. 187 */ 188struct ext2_dx_root_info { 189 __u32 reserved_zero; 190 __u8 hash_version; /* 0 now, 1 at release */ 191 __u8 info_length; /* 8 */ 192 __u8 indirect_levels; 193 __u8 unused_flags; 194}; 195 196#define EXT2_HASH_LEGACY 0 197#define EXT2_HASH_HALF_MD4 1 198#define EXT2_HASH_TEA 2 199#define EXT2_HASH_LEGACY_UNSIGNED 3 /* reserved for userspace lib */ 200#define EXT2_HASH_HALF_MD4_UNSIGNED 4 /* reserved for userspace lib */ 201#define EXT2_HASH_TEA_UNSIGNED 5 /* reserved for userspace lib */ 202 203#define EXT2_HASH_FLAG_INCOMPAT 0x1 204 205struct ext2_dx_entry { 206 __u32 hash; 207 __u32 block; 208}; 209 210struct ext2_dx_countlimit { 211 __u16 limit; 212 __u16 count; 213}; 214 215 216/* 217 * Macro-instructions used to manage group descriptors 218 */ 219#define EXT2_MIN_DESC_SIZE 32 220#define EXT2_MIN_DESC_SIZE_64BIT 64 221#define EXT2_MAX_DESC_SIZE EXT2_MIN_BLOCK_SIZE 222#define EXT2_DESC_SIZE(s) \ 223 ((EXT2_SB(s)->s_feature_incompat & EXT4_FEATURE_INCOMPAT_64BIT) ? \ 224 (s)->s_desc_size : EXT2_MIN_DESC_SIZE) 225 226#define EXT2_BLOCKS_PER_GROUP(s) (EXT2_SB(s)->s_blocks_per_group) 227#define EXT2_INODES_PER_GROUP(s) (EXT2_SB(s)->s_inodes_per_group) 228#define EXT2_INODES_PER_BLOCK(s) (EXT2_BLOCK_SIZE(s)/EXT2_INODE_SIZE(s)) 229/* limits imposed by 16-bit value gd_free_{blocks,inode}_count */ 230#define EXT2_MAX_BLOCKS_PER_GROUP(s) ((1 << 16) - 8) 231#define EXT2_MAX_INODES_PER_GROUP(s) ((1 << 16) - EXT2_INODES_PER_BLOCK(s)) 232#ifdef __KERNEL__ 233#define EXT2_DESC_PER_BLOCK(s) (EXT2_SB(s)->s_desc_per_block) 234#define EXT2_DESC_PER_BLOCK_BITS(s) (EXT2_SB(s)->s_desc_per_block_bits) 235#else 236#define EXT2_DESC_PER_BLOCK(s) (EXT2_BLOCK_SIZE(s) / EXT2_DESC_SIZE(s)) 237#endif 238 239/* 240 * Constants relative to the data blocks 241 */ 242#define EXT2_NDIR_BLOCKS 12 243#define EXT2_IND_BLOCK EXT2_NDIR_BLOCKS 244#define EXT2_DIND_BLOCK (EXT2_IND_BLOCK + 1) 245#define EXT2_TIND_BLOCK (EXT2_DIND_BLOCK + 1) 246#define EXT2_N_BLOCKS (EXT2_TIND_BLOCK + 1) 247 248/* 249 * Inode flags 250 */ 251#define EXT2_SECRM_FL 0x00000001 /* Secure deletion */ 252#define EXT2_UNRM_FL 0x00000002 /* Undelete */ 253#define EXT2_COMPR_FL 0x00000004 /* Compress file */ 254#define EXT2_SYNC_FL 0x00000008 /* Synchronous updates */ 255#define EXT2_IMMUTABLE_FL 0x00000010 /* Immutable file */ 256#define EXT2_APPEND_FL 0x00000020 /* writes to file may only append */ 257#define EXT2_NODUMP_FL 0x00000040 /* do not dump file */ 258#define EXT2_NOATIME_FL 0x00000080 /* do not update atime */ 259/* Reserved for compression usage... */ 260#define EXT2_DIRTY_FL 0x00000100 261#define EXT2_COMPRBLK_FL 0x00000200 /* One or more compressed clusters */ 262#define EXT2_NOCOMPR_FL 0x00000400 /* Access raw compressed data */ 263#define EXT2_ECOMPR_FL 0x00000800 /* Compression error */ 264/* End compression flags --- maybe not all used */ 265#define EXT2_BTREE_FL 0x00001000 /* btree format dir */ 266#define EXT2_INDEX_FL 0x00001000 /* hash-indexed directory */ 267#define EXT2_IMAGIC_FL 0x00002000 268#define EXT3_JOURNAL_DATA_FL 0x00004000 /* file data should be journaled */ 269#define EXT2_NOTAIL_FL 0x00008000 /* file tail should not be merged */ 270#define EXT2_DIRSYNC_FL 0x00010000 /* Synchronous directory modifications */ 271#define EXT2_TOPDIR_FL 0x00020000 /* Top of directory hierarchies*/ 272#define EXT4_HUGE_FILE_FL 0x00040000 /* Set to each huge file */ 273#define EXT4_EXTENTS_FL 0x00080000 /* Inode uses extents */ 274#define EXT4_EA_INODE_FL 0x00200000 /* Inode used for large EA */ 275#define EXT4_EOFBLOCKS_FL 0x00400000 /* Blocks allocated beyond EOF */ 276#define EXT4_SNAPFILE_FL 0x01000000 /* Inode is a snapshot */ 277#define EXT4_SNAPFILE_DELETED_FL 0x04000000 /* Snapshot is being deleted */ 278#define EXT4_SNAPFILE_SHRUNK_FL 0x08000000 /* Snapshot shrink has completed */ 279#define EXT2_RESERVED_FL 0x80000000 /* reserved for ext2 lib */ 280 281#define EXT2_FL_USER_VISIBLE 0x004BDFFF /* User visible flags */ 282#define EXT2_FL_USER_MODIFIABLE 0x004B80FF /* User modifiable flags */ 283 284/* 285 * ioctl commands 286 */ 287 288/* Used for online resize */ 289struct ext2_new_group_input { 290 __u32 group; /* Group number for this data */ 291 __u32 block_bitmap; /* Absolute block number of block bitmap */ 292 __u32 inode_bitmap; /* Absolute block number of inode bitmap */ 293 __u32 inode_table; /* Absolute block number of inode table start */ 294 __u32 blocks_count; /* Total number of blocks in this group */ 295 __u16 reserved_blocks; /* Number of reserved blocks in this group */ 296 __u16 unused; /* Number of reserved GDT blocks in group */ 297}; 298 299struct ext4_new_group_input { 300 __u32 group; /* Group number for this data */ 301 __u64 block_bitmap; /* Absolute block number of block bitmap */ 302 __u64 inode_bitmap; /* Absolute block number of inode bitmap */ 303 __u64 inode_table; /* Absolute block number of inode table start */ 304 __u32 blocks_count; /* Total number of blocks in this group */ 305 __u16 reserved_blocks; /* Number of reserved blocks in this group */ 306 __u16 unused; 307}; 308 309#ifdef __GNU__ /* Needed for the Hurd */ 310#define _IOT_ext2_new_group_input _IOT (_IOTS(__u32), 5, _IOTS(__u16), 2, 0, 0) 311#endif 312 313#define EXT2_IOC_GETFLAGS _IOR('f', 1, long) 314#define EXT2_IOC_SETFLAGS _IOW('f', 2, long) 315#define EXT2_IOC_GETVERSION _IOR('v', 1, long) 316#define EXT2_IOC_SETVERSION _IOW('v', 2, long) 317#define EXT2_IOC_GETVERSION_NEW _IOR('f', 3, long) 318#define EXT2_IOC_SETVERSION_NEW _IOW('f', 4, long) 319#define EXT2_IOC_GROUP_EXTEND _IOW('f', 7, unsigned long) 320#define EXT2_IOC_GROUP_ADD _IOW('f', 8,struct ext2_new_group_input) 321#define EXT4_IOC_GROUP_ADD _IOW('f', 8,struct ext4_new_group_input) 322 323/* 324 * Structure of an inode on the disk 325 */ 326struct ext2_inode { 327 __u16 i_mode; /* File mode */ 328 __u16 i_uid; /* Low 16 bits of Owner Uid */ 329 __u32 i_size; /* Size in bytes */ 330 __u32 i_atime; /* Access time */ 331 __u32 i_ctime; /* Inode change time */ 332 __u32 i_mtime; /* Modification time */ 333 __u32 i_dtime; /* Deletion Time */ 334 __u16 i_gid; /* Low 16 bits of Group Id */ 335 __u16 i_links_count; /* Links count */ 336 __u32 i_blocks; /* Blocks count */ 337 __u32 i_flags; /* File flags */ 338 union { 339 struct { 340 __u32 l_i_version; /* was l_i_reserved1 */ 341 } linux1; 342 struct { 343 __u32 h_i_translator; 344 } hurd1; 345 } osd1; /* OS dependent 1 */ 346 __u32 i_block[EXT2_N_BLOCKS];/* Pointers to blocks */ 347 __u32 i_generation; /* File version (for NFS) */ 348 __u32 i_file_acl; /* File ACL */ 349 __u32 i_dir_acl; /* Directory ACL */ 350 __u32 i_faddr; /* Fragment address */ 351 union { 352 struct { 353 __u16 l_i_blocks_hi; 354 __u16 l_i_file_acl_high; 355 __u16 l_i_uid_high; /* these 2 fields */ 356 __u16 l_i_gid_high; /* were reserved2[0] */ 357 __u32 l_i_reserved2; 358 } linux2; 359 struct { 360 __u8 h_i_frag; /* Fragment number */ 361 __u8 h_i_fsize; /* Fragment size */ 362 __u16 h_i_mode_high; 363 __u16 h_i_uid_high; 364 __u16 h_i_gid_high; 365 __u32 h_i_author; 366 } hurd2; 367 } osd2; /* OS dependent 2 */ 368}; 369 370/* 371 * Permanent part of an large inode on the disk 372 */ 373struct ext2_inode_large { 374 __u16 i_mode; /* File mode */ 375 __u16 i_uid; /* Low 16 bits of Owner Uid */ 376 __u32 i_size; /* Size in bytes */ 377 __u32 i_atime; /* Access time */ 378 __u32 i_ctime; /* Inode Change time */ 379 __u32 i_mtime; /* Modification time */ 380 __u32 i_dtime; /* Deletion Time */ 381 __u16 i_gid; /* Low 16 bits of Group Id */ 382 __u16 i_links_count; /* Links count */ 383 __u32 i_blocks; /* Blocks count */ 384 __u32 i_flags; /* File flags */ 385 union { 386 struct { 387 __u32 l_i_version; /* was l_i_reserved1 */ 388 } linux1; 389 struct { 390 __u32 h_i_translator; 391 } hurd1; 392 } osd1; /* OS dependent 1 */ 393 __u32 i_block[EXT2_N_BLOCKS];/* Pointers to blocks */ 394 __u32 i_generation; /* File version (for NFS) */ 395 __u32 i_file_acl; /* File ACL */ 396 __u32 i_dir_acl; /* Directory ACL */ 397 __u32 i_faddr; /* Fragment address */ 398 union { 399 struct { 400 __u16 l_i_blocks_hi; 401 __u16 l_i_file_acl_high; 402 __u16 l_i_uid_high; /* these 2 fields */ 403 __u16 l_i_gid_high; /* were reserved2[0] */ 404 __u32 l_i_reserved2; 405 } linux2; 406 struct { 407 __u8 h_i_frag; /* Fragment number */ 408 __u8 h_i_fsize; /* Fragment size */ 409 __u16 h_i_mode_high; 410 __u16 h_i_uid_high; 411 __u16 h_i_gid_high; 412 __u32 h_i_author; 413 } hurd2; 414 } osd2; /* OS dependent 2 */ 415 __u16 i_extra_isize; 416 __u16 i_pad1; 417 __u32 i_ctime_extra; /* extra Change time (nsec << 2 | epoch) */ 418 __u32 i_mtime_extra; /* extra Modification time (nsec << 2 | epoch) */ 419 __u32 i_atime_extra; /* extra Access time (nsec << 2 | epoch) */ 420 __u32 i_crtime; /* File creation time */ 421 __u32 i_crtime_extra; /* extra File creation time (nsec << 2 | epoch)*/ 422 __u32 i_version_hi; /* high 32 bits for 64-bit version */ 423}; 424 425#define i_size_high i_dir_acl 426 427#if defined(__KERNEL__) || defined(__linux__) 428#define i_reserved1 osd1.linux1.l_i_reserved1 429#define i_frag osd2.linux2.l_i_frag 430#define i_fsize osd2.linux2.l_i_fsize 431#define i_uid_low i_uid 432#define i_gid_low i_gid 433#define i_uid_high osd2.linux2.l_i_uid_high 434#define i_gid_high osd2.linux2.l_i_gid_high 435#define i_reserved2 osd2.linux2.l_i_reserved2 436#else 437#if defined(__GNU__) 438 439#define i_translator osd1.hurd1.h_i_translator 440#define i_frag osd2.hurd2.h_i_frag; 441#define i_fsize osd2.hurd2.h_i_fsize; 442#define i_uid_high osd2.hurd2.h_i_uid_high 443#define i_gid_high osd2.hurd2.h_i_gid_high 444#define i_author osd2.hurd2.h_i_author 445 446#endif /* __GNU__ */ 447#endif /* defined(__KERNEL__) || defined(__linux__) */ 448 449#define inode_uid(inode) ((inode).i_uid | (inode).osd2.linux2.l_i_uid_high << 16) 450#define inode_gid(inode) ((inode).i_gid | (inode).osd2.linux2.l_i_gid_high << 16) 451#define ext2fs_set_i_uid_high(inode,x) ((inode).osd2.linux2.l_i_uid_high = (x)) 452#define ext2fs_set_i_gid_high(inode,x) ((inode).osd2.linux2.l_i_gid_high = (x)) 453 454/* 455 * File system states 456 */ 457#define EXT2_VALID_FS 0x0001 /* Unmounted cleanly */ 458#define EXT2_ERROR_FS 0x0002 /* Errors detected */ 459#define EXT3_ORPHAN_FS 0x0004 /* Orphans being recovered */ 460 461/* 462 * Misc. filesystem flags 463 */ 464#define EXT2_FLAGS_SIGNED_HASH 0x0001 /* Signed dirhash in use */ 465#define EXT2_FLAGS_UNSIGNED_HASH 0x0002 /* Unsigned dirhash in use */ 466#define EXT2_FLAGS_TEST_FILESYS 0x0004 /* OK for use on development code */ 467#define EXT2_FLAGS_IS_SNAPSHOT 0x0010 /* This is a snapshot image */ 468#define EXT2_FLAGS_FIX_SNAPSHOT 0x0020 /* Snapshot inodes corrupted */ 469#define EXT2_FLAGS_FIX_EXCLUDE 0x0040 /* Exclude bitmaps corrupted */ 470 471/* 472 * Mount flags 473 */ 474#define EXT2_MOUNT_CHECK 0x0001 /* Do mount-time checks */ 475#define EXT2_MOUNT_GRPID 0x0004 /* Create files with directory's group */ 476#define EXT2_MOUNT_DEBUG 0x0008 /* Some debugging messages */ 477#define EXT2_MOUNT_ERRORS_CONT 0x0010 /* Continue on errors */ 478#define EXT2_MOUNT_ERRORS_RO 0x0020 /* Remount fs ro on errors */ 479#define EXT2_MOUNT_ERRORS_PANIC 0x0040 /* Panic on errors */ 480#define EXT2_MOUNT_MINIX_DF 0x0080 /* Mimics the Minix statfs */ 481#define EXT2_MOUNT_NO_UID32 0x0200 /* Disable 32-bit UIDs */ 482 483#define clear_opt(o, opt) o &= ~EXT2_MOUNT_##opt 484#define set_opt(o, opt) o |= EXT2_MOUNT_##opt 485#define test_opt(sb, opt) (EXT2_SB(sb)->s_mount_opt & \ 486 EXT2_MOUNT_##opt) 487/* 488 * Maximal mount counts between two filesystem checks 489 */ 490#define EXT2_DFL_MAX_MNT_COUNT 20 /* Allow 20 mounts */ 491#define EXT2_DFL_CHECKINTERVAL 0 /* Don't use interval check */ 492 493/* 494 * Behaviour when detecting errors 495 */ 496#define EXT2_ERRORS_CONTINUE 1 /* Continue execution */ 497#define EXT2_ERRORS_RO 2 /* Remount fs read-only */ 498#define EXT2_ERRORS_PANIC 3 /* Panic */ 499#define EXT2_ERRORS_DEFAULT EXT2_ERRORS_CONTINUE 500 501#if (__GNUC__ >= 4) 502#define ext4_offsetof(TYPE,MEMBER) __builtin_offsetof(TYPE,MEMBER) 503#else 504#define ext4_offsetof(TYPE, MEMBER) ((size_t) &((TYPE *)0)->MEMBER) 505#endif 506 507/* 508 * Structure of the super block 509 */ 510struct ext2_super_block { 511 __u32 s_inodes_count; /* Inodes count */ 512 __u32 s_blocks_count; /* Blocks count */ 513 __u32 s_r_blocks_count; /* Reserved blocks count */ 514 __u32 s_free_blocks_count; /* Free blocks count */ 515 __u32 s_free_inodes_count; /* Free inodes count */ 516 __u32 s_first_data_block; /* First Data Block */ 517 __u32 s_log_block_size; /* Block size */ 518 __s32 s_log_cluster_size; /* Allocation cluster size */ 519 __u32 s_blocks_per_group; /* # Blocks per group */ 520 __u32 s_clusters_per_group; /* # Fragments per group */ 521 __u32 s_inodes_per_group; /* # Inodes per group */ 522 __u32 s_mtime; /* Mount time */ 523 __u32 s_wtime; /* Write time */ 524 __u16 s_mnt_count; /* Mount count */ 525 __s16 s_max_mnt_count; /* Maximal mount count */ 526 __u16 s_magic; /* Magic signature */ 527 __u16 s_state; /* File system state */ 528 __u16 s_errors; /* Behaviour when detecting errors */ 529 __u16 s_minor_rev_level; /* minor revision level */ 530 __u32 s_lastcheck; /* time of last check */ 531 __u32 s_checkinterval; /* max. time between checks */ 532 __u32 s_creator_os; /* OS */ 533 __u32 s_rev_level; /* Revision level */ 534 __u16 s_def_resuid; /* Default uid for reserved blocks */ 535 __u16 s_def_resgid; /* Default gid for reserved blocks */ 536 /* 537 * These fields are for EXT2_DYNAMIC_REV superblocks only. 538 * 539 * Note: the difference between the compatible feature set and 540 * the incompatible feature set is that if there is a bit set 541 * in the incompatible feature set that the kernel doesn't 542 * know about, it should refuse to mount the filesystem. 543 * 544 * e2fsck's requirements are more strict; if it doesn't know 545 * about a feature in either the compatible or incompatible 546 * feature set, it must abort and not try to meddle with 547 * things it doesn't understand... 548 */ 549 __u32 s_first_ino; /* First non-reserved inode */ 550 __u16 s_inode_size; /* size of inode structure */ 551 __u16 s_block_group_nr; /* block group # of this superblock */ 552 __u32 s_feature_compat; /* compatible feature set */ 553 __u32 s_feature_incompat; /* incompatible feature set */ 554 __u32 s_feature_ro_compat; /* readonly-compatible feature set */ 555 __u8 s_uuid[16]; /* 128-bit uuid for volume */ 556 char s_volume_name[16]; /* volume name */ 557 char s_last_mounted[64]; /* directory where last mounted */ 558 __u32 s_algorithm_usage_bitmap; /* For compression */ 559 /* 560 * Performance hints. Directory preallocation should only 561 * happen if the EXT2_FEATURE_COMPAT_DIR_PREALLOC flag is on. 562 */ 563 __u8 s_prealloc_blocks; /* Nr of blocks to try to preallocate*/ 564 __u8 s_prealloc_dir_blocks; /* Nr to preallocate for dirs */ 565 __u16 s_reserved_gdt_blocks; /* Per group table for online growth */ 566 /* 567 * Journaling support valid if EXT2_FEATURE_COMPAT_HAS_JOURNAL set. 568 */ 569 __u8 s_journal_uuid[16]; /* uuid of journal superblock */ 570 __u32 s_journal_inum; /* inode number of journal file */ 571 __u32 s_journal_dev; /* device number of journal file */ 572 __u32 s_last_orphan; /* start of list of inodes to delete */ 573 __u32 s_hash_seed[4]; /* HTREE hash seed */ 574 __u8 s_def_hash_version; /* Default hash version to use */ 575 __u8 s_jnl_backup_type; /* Default type of journal backup */ 576 __u16 s_desc_size; /* Group desc. size: INCOMPAT_64BIT */ 577 __u32 s_default_mount_opts; 578 __u32 s_first_meta_bg; /* First metablock group */ 579 __u32 s_mkfs_time; /* When the filesystem was created */ 580 __u32 s_jnl_blocks[17]; /* Backup of the journal inode */ 581 __u32 s_blocks_count_hi; /* Blocks count high 32bits */ 582 __u32 s_r_blocks_count_hi; /* Reserved blocks count high 32 bits*/ 583 __u32 s_free_blocks_hi; /* Free blocks count */ 584 __u16 s_min_extra_isize; /* All inodes have at least # bytes */ 585 __u16 s_want_extra_isize; /* New inodes should reserve # bytes */ 586 __u32 s_flags; /* Miscellaneous flags */ 587 __u16 s_raid_stride; /* RAID stride */ 588 __u16 s_mmp_interval; /* # seconds to wait in MMP checking */ 589 __u64 s_mmp_block; /* Block for multi-mount protection */ 590 __u32 s_raid_stripe_width; /* blocks on all data disks (N*stride)*/ 591 __u8 s_log_groups_per_flex; /* FLEX_BG group size */ 592 __u8 s_reserved_char_pad; 593 __u16 s_reserved_pad; /* Padding to next 32bits */ 594 __u64 s_kbytes_written; /* nr of lifetime kilobytes written */ 595 __u32 s_snapshot_inum; /* Inode number of active snapshot */ 596 __u32 s_snapshot_id; /* sequential ID of active snapshot */ 597 __u64 s_snapshot_r_blocks_count; /* reserved blocks for active 598 snapshot's future use */ 599 __u32 s_snapshot_list; /* inode number of the head of the on-disk snapshot list */ 600#define EXT4_S_ERR_START ext4_offsetof(struct ext2_super_block, s_error_count) 601 __u32 s_error_count; /* number of fs errors */ 602 __u32 s_first_error_time; /* first time an error happened */ 603 __u32 s_first_error_ino; /* inode involved in first error */ 604 __u64 s_first_error_block; /* block involved of first error */ 605 __u8 s_first_error_func[32]; /* function where the error happened */ 606 __u32 s_first_error_line; /* line number where error happened */ 607 __u32 s_last_error_time; /* most recent time of an error */ 608 __u32 s_last_error_ino; /* inode involved in last error */ 609 __u32 s_last_error_line; /* line number where error happened */ 610 __u64 s_last_error_block; /* block involved of last error */ 611 __u8 s_last_error_func[32]; /* function where the error happened */ 612#define EXT4_S_ERR_END ext4_offsetof(struct ext2_super_block, s_mount_opts) 613 __u8 s_mount_opts[64]; 614 __u32 s_usr_quota_inum; /* inode number of user quota file */ 615 __u32 s_grp_quota_inum; /* inode number of group quota file */ 616 __u32 s_reserved[110]; /* Padding to the end of the block */ 617}; 618 619#define EXT4_S_ERR_LEN (EXT4_S_ERR_END - EXT4_S_ERR_START) 620 621/* 622 * Codes for operating systems 623 */ 624#define EXT2_OS_LINUX 0 625#define EXT2_OS_HURD 1 626#define EXT2_OBSO_OS_MASIX 2 627#define EXT2_OS_FREEBSD 3 628#define EXT2_OS_LITES 4 629 630/* 631 * Revision levels 632 */ 633#define EXT2_GOOD_OLD_REV 0 /* The good old (original) format */ 634#define EXT2_DYNAMIC_REV 1 /* V2 format w/ dynamic inode sizes */ 635 636#define EXT2_CURRENT_REV EXT2_GOOD_OLD_REV 637#define EXT2_MAX_SUPP_REV EXT2_DYNAMIC_REV 638 639#define EXT2_GOOD_OLD_INODE_SIZE 128 640 641/* 642 * Journal inode backup types 643 */ 644#define EXT3_JNL_BACKUP_BLOCKS 1 645 646/* 647 * Feature set definitions 648 */ 649 650#define EXT2_HAS_COMPAT_FEATURE(sb,mask) \ 651 ( EXT2_SB(sb)->s_feature_compat & (mask) ) 652#define EXT2_HAS_RO_COMPAT_FEATURE(sb,mask) \ 653 ( EXT2_SB(sb)->s_feature_ro_compat & (mask) ) 654#define EXT2_HAS_INCOMPAT_FEATURE(sb,mask) \ 655 ( EXT2_SB(sb)->s_feature_incompat & (mask) ) 656 657#define EXT2_FEATURE_COMPAT_DIR_PREALLOC 0x0001 658#define EXT2_FEATURE_COMPAT_IMAGIC_INODES 0x0002 659#define EXT3_FEATURE_COMPAT_HAS_JOURNAL 0x0004 660#define EXT2_FEATURE_COMPAT_EXT_ATTR 0x0008 661#define EXT2_FEATURE_COMPAT_RESIZE_INODE 0x0010 662#define EXT2_FEATURE_COMPAT_DIR_INDEX 0x0020 663#define EXT2_FEATURE_COMPAT_LAZY_BG 0x0040 664#define EXT2_FEATURE_COMPAT_EXCLUDE_INODE 0x0080 665 666#define EXT2_FEATURE_RO_COMPAT_SPARSE_SUPER 0x0001 667#define EXT2_FEATURE_RO_COMPAT_LARGE_FILE 0x0002 668/* #define EXT2_FEATURE_RO_COMPAT_BTREE_DIR 0x0004 not used */ 669#define EXT4_FEATURE_RO_COMPAT_HUGE_FILE 0x0008 670#define EXT4_FEATURE_RO_COMPAT_GDT_CSUM 0x0010 671#define EXT4_FEATURE_RO_COMPAT_DIR_NLINK 0x0020 672#define EXT4_FEATURE_RO_COMPAT_EXTRA_ISIZE 0x0040 673#define EXT4_FEATURE_RO_COMPAT_HAS_SNAPSHOT 0x0080 674#define EXT4_FEATURE_RO_COMPAT_QUOTA 0x0100 675#define EXT4_FEATURE_RO_COMPAT_BIGALLOC 0x0200 676 677#define EXT2_FEATURE_INCOMPAT_COMPRESSION 0x0001 678#define EXT2_FEATURE_INCOMPAT_FILETYPE 0x0002 679#define EXT3_FEATURE_INCOMPAT_RECOVER 0x0004 /* Needs recovery */ 680#define EXT3_FEATURE_INCOMPAT_JOURNAL_DEV 0x0008 /* Journal device */ 681#define EXT2_FEATURE_INCOMPAT_META_BG 0x0010 682#define EXT3_FEATURE_INCOMPAT_EXTENTS 0x0040 683#define EXT4_FEATURE_INCOMPAT_64BIT 0x0080 684#define EXT4_FEATURE_INCOMPAT_MMP 0x0100 685#define EXT4_FEATURE_INCOMPAT_FLEX_BG 0x0200 686#define EXT4_FEATURE_INCOMPAT_EA_INODE 0x0400 687#define EXT4_FEATURE_INCOMPAT_DIRDATA 0x1000 688 689#define EXT2_FEATURE_COMPAT_SUPP 0 690#define EXT2_FEATURE_INCOMPAT_SUPP (EXT2_FEATURE_INCOMPAT_FILETYPE) 691#define EXT2_FEATURE_RO_COMPAT_SUPP (EXT2_FEATURE_RO_COMPAT_SPARSE_SUPER| \ 692 EXT2_FEATURE_RO_COMPAT_LARGE_FILE| \ 693 EXT4_FEATURE_RO_COMPAT_DIR_NLINK| \ 694 EXT2_FEATURE_RO_COMPAT_BTREE_DIR) 695 696/* 697 * Default values for user and/or group using reserved blocks 698 */ 699#define EXT2_DEF_RESUID 0 700#define EXT2_DEF_RESGID 0 701 702/* 703 * Default mount options 704 */ 705#define EXT2_DEFM_DEBUG 0x0001 706#define EXT2_DEFM_BSDGROUPS 0x0002 707#define EXT2_DEFM_XATTR_USER 0x0004 708#define EXT2_DEFM_ACL 0x0008 709#define EXT2_DEFM_UID16 0x0010 710#define EXT3_DEFM_JMODE 0x0060 711#define EXT3_DEFM_JMODE_DATA 0x0020 712#define EXT3_DEFM_JMODE_ORDERED 0x0040 713#define EXT3_DEFM_JMODE_WBACK 0x0060 714#define EXT4_DEFM_NOBARRIER 0x0100 715#define EXT4_DEFM_BLOCK_VALIDITY 0x0200 716#define EXT4_DEFM_DISCARD 0x0400 717#define EXT4_DEFM_NODELALLOC 0x0800 718 719/* 720 * Structure of a directory entry 721 */ 722#define EXT2_NAME_LEN 255 723 724struct ext2_dir_entry { 725 __u32 inode; /* Inode number */ 726 __u16 rec_len; /* Directory entry length */ 727 __u16 name_len; /* Name length */ 728 char name[EXT2_NAME_LEN]; /* File name */ 729}; 730 731/* 732 * The new version of the directory entry. Since EXT2 structures are 733 * stored in intel byte order, and the name_len field could never be 734 * bigger than 255 chars, it's safe to reclaim the extra byte for the 735 * file_type field. 736 */ 737struct ext2_dir_entry_2 { 738 __u32 inode; /* Inode number */ 739 __u16 rec_len; /* Directory entry length */ 740 __u8 name_len; /* Name length */ 741 __u8 file_type; 742 char name[EXT2_NAME_LEN]; /* File name */ 743}; 744 745/* 746 * Ext2 directory file types. Only the low 3 bits are used. The 747 * other bits are reserved for now. 748 */ 749#define EXT2_FT_UNKNOWN 0 750#define EXT2_FT_REG_FILE 1 751#define EXT2_FT_DIR 2 752#define EXT2_FT_CHRDEV 3 753#define EXT2_FT_BLKDEV 4 754#define EXT2_FT_FIFO 5 755#define EXT2_FT_SOCK 6 756#define EXT2_FT_SYMLINK 7 757 758#define EXT2_FT_MAX 8 759 760/* 761 * EXT2_DIR_PAD defines the directory entries boundaries 762 * 763 * NOTE: It must be a multiple of 4 764 */ 765#define EXT2_DIR_PAD 4 766#define EXT2_DIR_ROUND (EXT2_DIR_PAD - 1) 767#define EXT2_DIR_REC_LEN(name_len) (((name_len) + 8 + EXT2_DIR_ROUND) & \ 768 ~EXT2_DIR_ROUND) 769 770/* 771 * This structure will be used for multiple mount protection. It will be 772 * written into the block number saved in the s_mmp_block field in the 773 * superblock. 774 */ 775#define EXT2_MMP_MAGIC 0x004D4D50 /* ASCII for MMP */ 776#define EXT2_MMP_CLEAN 0xFF4D4D50 /* Value of mmp_seq for clean unmount */ 777#define EXT2_MMP_FSCK_ON 0xE24D4D50 /* Value of mmp_seq when being fscked */ 778 779struct mmp_struct { 780 __u32 mmp_magic; 781 __u32 mmp_seq; 782 __u64 mmp_time; 783 char mmp_nodename[64]; 784 char mmp_bdevname[32]; 785 __u16 mmp_interval; 786 __u16 mmp_pad1; 787 __u32 mmp_pad2; 788}; 789 790/* 791 * Interval in number of seconds to update the MMP sequence number. 792 */ 793#define EXT2_MMP_DEF_INTERVAL 5 794 795#endif /* _LINUX_EXT2_FS_H */ 796