2 * linux/include/linux/ext2_fs.h
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)
11 * linux/include/linux/minix_fs.h
13 * Copyright (C) 1991, 1992 Linus Torvalds
16 #ifndef _LINUX_EXT2_FS_H
17 #define _LINUX_EXT2_FS_H
19 #include <ext2fs/ext2_types.h> /* Changed from linux/types.h */
22 * The second extended filesystem constants/structures
26 * Define EXT2FS_DEBUG to produce debug messages
31 * Define EXT2_PREALLOCATE to preallocate data blocks for expanding files
33 #define EXT2_PREALLOCATE
34 #define EXT2_DEFAULT_PREALLOC_BLOCKS 8
37 * The second extended file system version
39 #define EXT2FS_DATE "95/08/09"
40 #define EXT2FS_VERSION "0.5b"
43 * Special inode numbers
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 */
54 /* First non-reserved inode for old ext2 filesystems */
55 #define EXT2_GOOD_OLD_FIRST_INO 11
58 * The second extended file system magic number
60 #define EXT2_SUPER_MAGIC 0xEF53
63 #define EXT2_SB(sb) (&((sb)->u.ext2_sb))
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)
72 * Maximal count of links to a file
74 #define EXT2_LINK_MAX 65000
77 * Macro-instructions used to manage several block sizes
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)
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)
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)
97 #define EXT2_ADDR_PER_BLOCK(s) (EXT2_BLOCK_SIZE(s) / sizeof(__u32))
100 * Macro-instructions used to manage fragments
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
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)
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))
116 struct ext2_acl_header /* Header of Access Control Lists */
119 __u32 aclh_file_count;
120 __u32 aclh_acle_count;
121 __u32 aclh_first_acle;
124 struct ext2_acl_entry /* Access Control List Entry */
127 __u16 acle_perms; /* Access permissions */
128 __u16 acle_type; /* Type of entry */
129 __u16 acle_tag; /* User or group identity */
131 __u32 acle_next; /* Pointer on next entry for the */
132 /* same inode or on next free entry */
136 * Structure of a blocks group descriptor
138 struct ext2_group_desc
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 */
147 __u32 bg_reserved[2];
148 __u16 bg_itable_unused; /* Unused inodes count */
149 __u16 bg_checksum; /* crc16(s_uuid+grouo_num+group_desc)*/
152 struct ext4_group_desc
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 */
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 */
171 __u32 bg_reserved2[3];
174 #define EXT2_BG_INODE_UNINIT 0x0001 /* Inode table/bitmap not initialized */
175 #define EXT2_BG_BLOCK_UNINIT 0x0002 /* Block bitmap not initialized */
178 * Data structures used by the directory indexing feature
180 * Note: all of the multibyte integer fields are little endian.
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.
189 struct ext2_dx_root_info {
191 __u8 hash_version; /* 0 now, 1 at release */
192 __u8 info_length; /* 8 */
193 __u8 indirect_levels;
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 */
204 #define EXT2_HASH_FLAG_INCOMPAT 0x1
206 struct ext2_dx_entry {
211 struct ext2_dx_countlimit {
218 * Macro-instructions used to manage group descriptors
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))
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)
230 #define EXT2_DESC_PER_BLOCK(s) (EXT2_BLOCK_SIZE(s) / sizeof (struct ext2_group_desc))
234 * Constants relative to the data blocks
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)
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 */
269 #define EXT2_FL_USER_VISIBLE 0x000BDFFF /* User visible flags */
270 #define EXT2_FL_USER_MODIFIABLE 0x000080FF /* User modifiable flags */
276 /* Used for online resize */
277 struct 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 */
287 #ifdef __GNU__ /* Needed for the Hurd */
288 #define _IOT_ext2_new_group_input _IOT (_IOTS(__u32), 5, _IOTS(__u16), 2, 0, 0)
291 #define EXT2_IOC_GETFLAGS _IOR('f', 1, long)
292 #define EXT2_IOC_SETFLAGS _IOW('f', 2, long)
293 #define EXT2_IOC_GETVERSION _IOR('v', 1, long)
294 #define EXT2_IOC_SETVERSION _IOW('v', 2, long)
295 #define EXT2_IOC_GETVERSION_NEW _IOR('f', 3, long)
296 #define EXT2_IOC_SETVERSION_NEW _IOW('f', 4, long)
297 #define EXT2_IOC_GROUP_EXTEND _IOW('f', 7, unsigned long)
298 #define EXT2_IOC_GROUP_ADD _IOW('f', 8,struct ext2_new_group_input)
301 * Structure of an inode on the disk
304 __u16 i_mode; /* File mode */
305 __u16 i_uid; /* Low 16 bits of Owner Uid */
306 __u32 i_size; /* Size in bytes */
307 __u32 i_atime; /* Access time */
308 __u32 i_ctime; /* Inode change time */
309 __u32 i_mtime; /* Modification time */
310 __u32 i_dtime; /* Deletion Time */
311 __u16 i_gid; /* Low 16 bits of Group Id */
312 __u16 i_links_count; /* Links count */
313 __u32 i_blocks; /* Blocks count */
314 __u32 i_flags; /* File flags */
317 __u32 l_i_version; /* was l_i_reserved1 */
320 __u32 h_i_translator;
325 } osd1; /* OS dependent 1 */
326 __u32 i_block[EXT2_N_BLOCKS];/* Pointers to blocks */
327 __u32 i_generation; /* File version (for NFS) */
328 __u32 i_file_acl; /* File ACL */
329 __u32 i_dir_acl; /* Directory ACL */
330 __u32 i_faddr; /* Fragment address */
335 __u16 l_i_uid_high; /* these 2 fields */
336 __u16 l_i_gid_high; /* were reserved2[0] */
340 __u8 h_i_frag; /* Fragment number */
341 __u8 h_i_fsize; /* Fragment size */
348 __u8 m_i_frag; /* Fragment number */
349 __u8 m_i_fsize; /* Fragment size */
351 __u32 m_i_reserved2[2];
353 } osd2; /* OS dependent 2 */
357 * Permanent part of an large inode on the disk
359 struct 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 */
373 __u32 l_i_version; /* was l_i_reserved1 */
376 __u32 h_i_translator;
381 } osd1; /* OS dependent 1 */
382 __u32 i_block[EXT2_N_BLOCKS];/* Pointers to blocks */
383 __u32 i_generation; /* File version (for NFS) */
384 __u32 i_file_acl; /* File ACL */
385 __u32 i_dir_acl; /* Directory ACL */
386 __u32 i_faddr; /* Fragment address */
391 __u16 l_i_uid_high; /* these 2 fields */
392 __u16 l_i_gid_high; /* were reserved2[0] */
396 __u8 h_i_frag; /* Fragment number */
397 __u8 h_i_fsize; /* Fragment size */
404 __u8 m_i_frag; /* Fragment number */
405 __u8 m_i_fsize; /* Fragment size */
407 __u32 m_i_reserved2[2];
409 } osd2; /* OS dependent 2 */
412 __u32 i_ctime_extra; /* extra Change time (nsec << 2 | epoch) */
413 __u32 i_mtime_extra; /* extra Modification time (nsec << 2 | epoch) */
414 __u32 i_atime_extra; /* extra Access time (nsec << 2 | epoch) */
415 __u32 i_crtime; /* File creation time */
416 __u32 i_crtime_extra; /* extra File creation time (nsec << 2 | epoch)*/
419 #define i_size_high i_dir_acl
421 #if defined(__KERNEL__) || defined(__linux__)
422 #define i_reserved1 osd1.linux1.l_i_reserved1
423 #define i_frag osd2.linux2.l_i_frag
424 #define i_fsize osd2.linux2.l_i_fsize
425 #define i_uid_low i_uid
426 #define i_gid_low i_gid
427 #define i_uid_high osd2.linux2.l_i_uid_high
428 #define i_gid_high osd2.linux2.l_i_gid_high
429 #define i_reserved2 osd2.linux2.l_i_reserved2
433 #define i_translator osd1.hurd1.h_i_translator
434 #define i_frag osd2.hurd2.h_i_frag;
435 #define i_fsize osd2.hurd2.h_i_fsize;
436 #define i_uid_high osd2.hurd2.h_i_uid_high
437 #define i_gid_high osd2.hurd2.h_i_gid_high
438 #define i_author osd2.hurd2.h_i_author
441 #if defined(__masix__)
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
448 #endif /* __masix__ */
450 #endif /* defined(__KERNEL__) || defined(__linux__) */
452 #if defined(__masix__)
453 #define inode_uid(inode) ((inode).i_uid)
454 #define inode_gid(inode) ((inode).i_gid)
455 #define ext2fs_set_i_uid_high(inode,x) (x)
456 #define ext2fs_set_i_gid_high(inode,x) (x)
459 #define inode_uid(inode) ((inode).i_uid | (inode).osd2.linux2.l_i_uid_high << 16)
460 #define inode_gid(inode) ((inode).i_gid | (inode).osd2.linux2.l_i_gid_high << 16)
461 #define ext2fs_set_i_uid_high(inode,x) ((inode).osd2.linux2.l_i_uid_high = (x))
462 #define ext2fs_set_i_gid_high(inode,x) ((inode).osd2.linux2.l_i_gid_high = (x))
468 #define EXT2_VALID_FS 0x0001 /* Unmounted cleanly */
469 #define EXT2_ERROR_FS 0x0002 /* Errors detected */
472 * Misc. filesystem flags
474 #define EXT2_FLAGS_SIGNED_HASH 0x0001 /* Signed dirhash in use */
475 #define EXT2_FLAGS_UNSIGNED_HASH 0x0002 /* Unsigned dirhash in use */
480 #define EXT2_MOUNT_CHECK 0x0001 /* Do mount-time checks */
481 #define EXT2_MOUNT_GRPID 0x0004 /* Create files with directory's group */
482 #define EXT2_MOUNT_DEBUG 0x0008 /* Some debugging messages */
483 #define EXT2_MOUNT_ERRORS_CONT 0x0010 /* Continue on errors */
484 #define EXT2_MOUNT_ERRORS_RO 0x0020 /* Remount fs ro on errors */
485 #define EXT2_MOUNT_ERRORS_PANIC 0x0040 /* Panic on errors */
486 #define EXT2_MOUNT_MINIX_DF 0x0080 /* Mimics the Minix statfs */
487 #define EXT2_MOUNT_NO_UID32 0x0200 /* Disable 32-bit UIDs */
489 #define clear_opt(o, opt) o &= ~EXT2_MOUNT_##opt
490 #define set_opt(o, opt) o |= EXT2_MOUNT_##opt
491 #define test_opt(sb, opt) (EXT2_SB(sb)->s_mount_opt & \
494 * Maximal mount counts between two filesystem checks
496 #define EXT2_DFL_MAX_MNT_COUNT 20 /* Allow 20 mounts */
497 #define EXT2_DFL_CHECKINTERVAL 0 /* Don't use interval check */
500 * Behaviour when detecting errors
502 #define EXT2_ERRORS_CONTINUE 1 /* Continue execution */
503 #define EXT2_ERRORS_RO 2 /* Remount fs read-only */
504 #define EXT2_ERRORS_PANIC 3 /* Panic */
505 #define EXT2_ERRORS_DEFAULT EXT2_ERRORS_CONTINUE
508 * Structure of the super block
510 struct 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_frag_size; /* Fragment size */
519 __u32 s_blocks_per_group; /* # Blocks per group */
520 __u32 s_frags_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 */
537 * These fields are for EXT2_DYNAMIC_REV superblocks only.
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.
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...
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 */
560 * Performance hints. Directory preallocation should only
561 * happen if the EXT2_FEATURE_COMPAT_DIR_PREALLOC flag is on.
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 */
567 * Journaling support valid if EXT2_FEATURE_COMPAT_HAS_JOURNAL set.
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 __u32 s_reserved[163]; /* Padding to the end of the block */
595 * Codes for operating systems
597 #define EXT2_OS_LINUX 0
598 #define EXT2_OS_HURD 1
599 #define EXT2_OS_MASIX 2
600 #define EXT2_OS_FREEBSD 3
601 #define EXT2_OS_LITES 4
606 #define EXT2_GOOD_OLD_REV 0 /* The good old (original) format */
607 #define EXT2_DYNAMIC_REV 1 /* V2 format w/ dynamic inode sizes */
609 #define EXT2_CURRENT_REV EXT2_GOOD_OLD_REV
610 #define EXT2_MAX_SUPP_REV EXT2_DYNAMIC_REV
612 #define EXT2_GOOD_OLD_INODE_SIZE 128
615 * Journal inode backup types
617 #define EXT3_JNL_BACKUP_BLOCKS 1
620 * Feature set definitions
623 #define EXT2_HAS_COMPAT_FEATURE(sb,mask) \
624 ( EXT2_SB(sb)->s_feature_compat & (mask) )
625 #define EXT2_HAS_RO_COMPAT_FEATURE(sb,mask) \
626 ( EXT2_SB(sb)->s_feature_ro_compat & (mask) )
627 #define EXT2_HAS_INCOMPAT_FEATURE(sb,mask) \
628 ( EXT2_SB(sb)->s_feature_incompat & (mask) )
630 #define EXT2_FEATURE_COMPAT_DIR_PREALLOC 0x0001
631 #define EXT2_FEATURE_COMPAT_IMAGIC_INODES 0x0002
632 #define EXT3_FEATURE_COMPAT_HAS_JOURNAL 0x0004
633 #define EXT2_FEATURE_COMPAT_EXT_ATTR 0x0008
634 #define EXT2_FEATURE_COMPAT_RESIZE_INODE 0x0010
635 #define EXT2_FEATURE_COMPAT_DIR_INDEX 0x0020
636 #define EXT2_FEATURE_COMPAT_LAZY_BG 0x0040
638 #define EXT2_FEATURE_RO_COMPAT_SPARSE_SUPER 0x0001
639 #define EXT2_FEATURE_RO_COMPAT_LARGE_FILE 0x0002
640 /* #define EXT2_FEATURE_RO_COMPAT_BTREE_DIR 0x0004 not used */
641 #define EXT4_FEATURE_RO_COMPAT_HUGE_FILE 0x0008
642 #define EXT4_FEATURE_RO_COMPAT_GDT_CSUM 0x0010
643 #define EXT4_FEATURE_RO_COMPAT_DIR_NLINK 0x0020
644 #define EXT4_FEATURE_RO_COMPAT_EXTRA_ISIZE 0x0040
646 #define EXT2_FEATURE_INCOMPAT_COMPRESSION 0x0001
647 #define EXT2_FEATURE_INCOMPAT_FILETYPE 0x0002
648 #define EXT3_FEATURE_INCOMPAT_RECOVER 0x0004 /* Needs recovery */
649 #define EXT3_FEATURE_INCOMPAT_JOURNAL_DEV 0x0008 /* Journal device */
650 #define EXT2_FEATURE_INCOMPAT_META_BG 0x0010
651 #define EXT3_FEATURE_INCOMPAT_EXTENTS 0x0040
652 #define EXT4_FEATURE_INCOMPAT_64BIT 0x0080
653 #define EXT4_FEATURE_INCOMPAT_MMP 0x0100
656 #define EXT2_FEATURE_COMPAT_SUPP 0
657 #define EXT2_FEATURE_INCOMPAT_SUPP (EXT2_FEATURE_INCOMPAT_FILETYPE)
658 #define EXT2_FEATURE_RO_COMPAT_SUPP (EXT2_FEATURE_RO_COMPAT_SPARSE_SUPER| \
659 EXT2_FEATURE_RO_COMPAT_LARGE_FILE| \
660 EXT2_FEATURE_RO_COMPAT_BTREE_DIR)
663 * Default values for user and/or group using reserved blocks
665 #define EXT2_DEF_RESUID 0
666 #define EXT2_DEF_RESGID 0
669 * Default mount options
671 #define EXT2_DEFM_DEBUG 0x0001
672 #define EXT2_DEFM_BSDGROUPS 0x0002
673 #define EXT2_DEFM_XATTR_USER 0x0004
674 #define EXT2_DEFM_ACL 0x0008
675 #define EXT2_DEFM_UID16 0x0010
676 #define EXT3_DEFM_JMODE 0x0060
677 #define EXT3_DEFM_JMODE_DATA 0x0020
678 #define EXT3_DEFM_JMODE_ORDERED 0x0040
679 #define EXT3_DEFM_JMODE_WBACK 0x0060
682 * Structure of a directory entry
684 #define EXT2_NAME_LEN 255
686 struct ext2_dir_entry {
687 __u32 inode; /* Inode number */
688 __u16 rec_len; /* Directory entry length */
689 __u16 name_len; /* Name length */
690 char name[EXT2_NAME_LEN]; /* File name */
694 * The new version of the directory entry. Since EXT2 structures are
695 * stored in intel byte order, and the name_len field could never be
696 * bigger than 255 chars, it's safe to reclaim the extra byte for the
699 struct ext2_dir_entry_2 {
700 __u32 inode; /* Inode number */
701 __u16 rec_len; /* Directory entry length */
702 __u8 name_len; /* Name length */
704 char name[EXT2_NAME_LEN]; /* File name */
708 * Ext2 directory file types. Only the low 3 bits are used. The
709 * other bits are reserved for now.
711 #define EXT2_FT_UNKNOWN 0
712 #define EXT2_FT_REG_FILE 1
713 #define EXT2_FT_DIR 2
714 #define EXT2_FT_CHRDEV 3
715 #define EXT2_FT_BLKDEV 4
716 #define EXT2_FT_FIFO 5
717 #define EXT2_FT_SOCK 6
718 #define EXT2_FT_SYMLINK 7
720 #define EXT2_FT_MAX 8
723 * EXT2_DIR_PAD defines the directory entries boundaries
725 * NOTE: It must be a multiple of 4
727 #define EXT2_DIR_PAD 4
728 #define EXT2_DIR_ROUND (EXT2_DIR_PAD - 1)
729 #define EXT2_DIR_REC_LEN(name_len) (((name_len) + 8 + EXT2_DIR_ROUND) & \
733 * This structure will be used for multiple mount protection. It will be
734 * written into the block number saved in the s_mmp_block field in the
737 #define EXT2_MMP_MAGIC 0x004D4D50 /* ASCII for MMP */
738 #define EXT2_MMP_CLEAN 0xFF4D4D50 /* Value of mmp_seq for clean unmount */
739 #define EXT2_MMP_FSCK_ON 0xE24D4D50 /* Value of mmp_seq when being fscked */
745 char mmp_nodename[64];
746 char mmp_bdevname[32];
753 * Interval in number of seconds to update the MMP sequence number.
755 #define EXT2_MMP_DEF_INTERVAL 5
757 #endif /* _LINUX_EXT2_FS_H */