2 * modified for EXT2FS support in Lites 1.1
4 * Aug 1995, Godmar Back (gback@cs.utah.edu)
5 * University of Utah, Department of Computer Science
10 * linux/include/linux/ext2_fs.h
12 * Copyright (C) 1992, 1993, 1994, 1995
13 * Remy Card (card@masi.ibp.fr)
14 * Laboratoire MASI - Institut Blaise Pascal
15 * Universite Pierre et Marie Curie (Paris VI)
19 * linux/include/linux/minix_fs.h
21 * Copyright (C) 1991, 1992 Linus Torvalds
23 * This program is free software; you can redistribute it and/or modify
24 * it under the terms of the GNU General Public License as published by
25 * the Free Software Foundation; either version 2 of the License.
27 * This program is distributed in the hope that it will be useful,
28 * but WITHOUT ANY WARRANTY; without even the implied warranty of
29 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
30 * GNU General Public License for more details.
32 * You should have received a copy of the GNU General Public License
33 * along with this program; if not, write to the Free Software
34 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
38 #ifndef _LINUX_EXT2_FS_H
39 #define _LINUX_EXT2_FS_H
41 #include <sys/types.h>
43 #define __u32 u_int32_t
45 #define __u16 u_int16_t
52 #define umode_t mode_t
56 * The second extended filesystem constants/structures
60 * Define EXT2FS_DEBUG to produce debug messages
65 * Define EXT2_PREALLOCATE to preallocate data blocks for expanding files
67 #define EXT2_PREALLOCATE
68 #define EXT2_DEFAULT_PREALLOC_BLOCKS 8
71 * The second extended file system version
73 #define EXT2FS_DATE "95/08/09"
74 #define EXT2FS_VERSION "0.5b"
80 # define ext2_debug(f, a...) { \
81 printf ("EXT2-fs DEBUG (%s, %d): %s:", \
82 __FILE__, __LINE__, __func__); \
86 # define ext2_debug(f, a...) /**/
90 * Special inodes numbers
92 #define EXT2_BAD_INO 1 /* Bad blocks inode */
93 #define EXT2_ROOT_INO 2 /* Root inode */
94 #define EXT2_ACL_IDX_INO 3 /* ACL inode */
95 #define EXT2_ACL_DATA_INO 4 /* ACL inode */
96 #define EXT2_BOOT_LOADER_INO 5 /* Boot loader inode */
97 #define EXT2_UNDEL_DIR_INO 6 /* Undelete directory inode */
99 /* First non-reserved inode for old ext2 filesystems */
100 #define EXT2_GOOD_OLD_FIRST_INO 11
103 * The second extended file system magic number
105 #define EXT2_SUPER_MAGIC 0xEF53
108 * Maximal count of links to a file
110 #define EXT2_LINK_MAX 32000
113 * Note: under FreeBSD, the "user" versions of the following macros are
114 * used (and must be used) in most cases, because ((s)->u.ext2_sb.s_es is
115 * not accessible. This depends on __KERNEL__ not being defined for
116 * kernel builds under FreeBSD.
120 * Macro-instructions used to manage several block sizes
122 #define EXT2_MIN_BLOCK_SIZE 1024
123 #define EXT2_MAX_BLOCK_SIZE 4096
124 #define EXT2_MIN_BLOCK_LOG_SIZE 10
125 #if defined(__KERNEL__) || (defined(__FreeBSD__) && defined(_KERNEL))
126 # define EXT2_BLOCK_SIZE(s) ((s)->s_blocksize)
128 # define EXT2_BLOCK_SIZE(s) (EXT2_MIN_BLOCK_SIZE << (s)->s_log_block_size)
130 #define EXT2_ACLE_PER_BLOCK(s) (EXT2_BLOCK_SIZE(s) / sizeof (struct ext2_acl_entry))
131 #define EXT2_ADDR_PER_BLOCK(s) (EXT2_BLOCK_SIZE(s) / sizeof (__u32))
133 # define EXT2_BLOCK_SIZE_BITS(s) ((s)->s_blocksize_bits)
135 # define EXT2_BLOCK_SIZE_BITS(s) ((s)->s_log_block_size + 10)
139 #define EXT2_ADDR_PER_BLOCK_BITS(s) ((s)->u.ext2_sb.s_addr_per_block_bits)
140 #define EXT2_INODE_SIZE(s) ((s)->u.ext2_sb.s_inode_size)
141 #define EXT2_FIRST_INO(s) ((s)->u.ext2_sb.s_first_ino)
143 #define EXT2_INODE_SIZE(s) (((s)->s_rev_level == EXT2_GOOD_OLD_REV) ? \
144 EXT2_GOOD_OLD_INODE_SIZE : \
146 #define EXT2_FIRST_INO(s) (((s)->s_rev_level == EXT2_GOOD_OLD_REV) ? \
147 EXT2_GOOD_OLD_FIRST_INO : \
151 #define EXT2_INODES_PER_BLOCK(s) ((s)->s_inodes_per_block)
152 /* Should be sizeof(struct ext2_inode): */
153 #define EXT2_INODE_SIZE 128
154 #define EXT2_FIRST_INO 11
158 * Macro-instructions used to manage fragments
160 #define EXT2_MIN_FRAG_SIZE 1024
161 #define EXT2_MAX_FRAG_SIZE 4096
162 #define EXT2_MIN_FRAG_LOG_SIZE 10
164 # define EXT2_FRAG_SIZE(s) ((s)->u.ext2_sb.s_frag_size)
165 # define EXT2_FRAGS_PER_BLOCK(s) ((s)->u.ext2_sb.s_frags_per_block)
167 # if defined(_KERNEL) && defined(__FreeBSD__)
168 # define EXT2_FRAG_SIZE(s) ((s)->s_frag_size)
170 # define EXT2_FRAG_SIZE(s) (EXT2_MIN_FRAG_SIZE << (s)->s_log_frag_size)
172 # define EXT2_FRAGS_PER_BLOCK(s) (EXT2_BLOCK_SIZE(s) / EXT2_FRAG_SIZE(s))
178 struct ext2_acl_header /* Header of Access Control Lists */
181 __u32 aclh_file_count;
182 __u32 aclh_acle_count;
183 __u32 aclh_first_acle;
186 struct ext2_acl_entry /* Access Control List Entry */
189 __u16 acle_perms; /* Access permissions */
190 __u16 acle_type; /* Type of entry */
191 __u16 acle_tag; /* User or group identity */
193 __u32 acle_next; /* Pointer on next entry for the */
194 /* same inode or on next free entry */
198 * Structure of a blocks group descriptor
200 struct ext2_group_desc
202 __u32 bg_block_bitmap; /* Blocks bitmap block */
203 __u32 bg_inode_bitmap; /* Inodes bitmap block */
204 __u32 bg_inode_table; /* Inodes table block */
205 __u16 bg_free_blocks_count; /* Free blocks count */
206 __u16 bg_free_inodes_count; /* Free inodes count */
207 __u16 bg_used_dirs_count; /* Directories count */
209 __u32 bg_reserved[3];
213 * Macro-instructions used to manage group descriptors
216 # define EXT2_BLOCKS_PER_GROUP(s) ((s)->u.ext2_sb.s_blocks_per_group)
217 # define EXT2_DESC_PER_BLOCK(s) ((s)->u.ext2_sb.s_desc_per_block)
218 # define EXT2_INODES_PER_GROUP(s) ((s)->u.ext2_sb.s_inodes_per_group)
219 # define EXT2_DESC_PER_BLOCK_BITS(s) ((s)->u.ext2_sb.s_desc_per_block_bits)
221 # define EXT2_BLOCKS_PER_GROUP(s) ((s)->s_blocks_per_group)
222 # define EXT2_DESC_PER_BLOCK(s) (EXT2_BLOCK_SIZE(s) / sizeof (struct ext2_group_desc))
223 # define EXT2_INODES_PER_GROUP(s) ((s)->s_inodes_per_group)
227 * Constants relative to the data blocks
229 #define EXT2_NDIR_BLOCKS 12
230 #define EXT2_IND_BLOCK EXT2_NDIR_BLOCKS
231 #define EXT2_DIND_BLOCK (EXT2_IND_BLOCK + 1)
232 #define EXT2_TIND_BLOCK (EXT2_DIND_BLOCK + 1)
233 #define EXT2_N_BLOCKS (EXT2_TIND_BLOCK + 1)
234 #define EXT2_MAXSYMLINKLEN (EXT2_N_BLOCKS * sizeof (__u32))
239 #define EXT2_SECRM_FL 0x00000001 /* Secure deletion */
240 #define EXT2_UNRM_FL 0x00000002 /* Undelete */
241 #define EXT2_COMPR_FL 0x00000004 /* Compress file */
242 #define EXT2_SYNC_FL 0x00000008 /* Synchronous updates */
243 #define EXT2_IMMUTABLE_FL 0x00000010 /* Immutable file */
244 #define EXT2_APPEND_FL 0x00000020 /* writes to file may only append */
245 #define EXT2_NODUMP_FL 0x00000040 /* do not dump file */
246 #define EXT2_NOATIME_FL 0x00000080 /* do not update atime */
247 /* Reserved for compression usage... */
248 #define EXT2_DIRTY_FL 0x00000100
249 #define EXT2_COMPRBLK_FL 0x00000200 /* One or more compressed clusters */
250 #define EXT2_NOCOMP_FL 0x00000400 /* Don't compress */
251 #define EXT2_ECOMPR_FL 0x00000800 /* Compression error */
252 /* End compression flags --- maybe not all used */
253 #define EXT2_BTREE_FL 0x00001000 /* btree format dir */
254 #define EXT2_RESERVED_FL 0x80000000 /* reserved for ext2 lib */
256 #define EXT2_FL_USER_VISIBLE 0x00001FFF /* User visible flags */
257 #define EXT2_FL_USER_MODIFIABLE 0x000000FF /* User modifiable flags */
262 #define EXT2_IOC_GETFLAGS _IOR('f', 1, long)
263 #define EXT2_IOC_SETFLAGS _IOW('f', 2, long)
264 #define EXT2_IOC_GETVERSION _IOR('v', 1, long)
265 #define EXT2_IOC_SETVERSION _IOW('v', 2, long)
268 * Structure of an inode on the disk
271 __u16 i_mode; /* File mode */
272 __u16 i_uid; /* Owner Uid */
273 __u32 i_size; /* Size in bytes */
274 __u32 i_atime; /* Access time */
275 __u32 i_ctime; /* Creation time */
276 __u32 i_mtime; /* Modification time */
277 __u32 i_dtime; /* Deletion Time */
278 __u16 i_gid; /* Group Id */
279 __u16 i_links_count; /* Links count */
280 __u32 i_blocks; /* Blocks count */
281 __u32 i_flags; /* File flags */
287 __u32 h_i_translator;
292 } osd1; /* OS dependent 1 */
293 __u32 i_block[EXT2_N_BLOCKS];/* Pointers to blocks */
294 __u32 i_generation; /* File version (for NFS) */
295 __u32 i_file_acl; /* File ACL */
296 __u32 i_dir_acl; /* Directory ACL */
297 __u32 i_faddr; /* Fragment address */
300 __u8 l_i_frag; /* Fragment number */
301 __u8 l_i_fsize; /* Fragment size */
303 __u32 l_i_reserved2[2];
306 __u8 h_i_frag; /* Fragment number */
307 __u8 h_i_fsize; /* Fragment size */
314 __u8 m_i_frag; /* Fragment number */
315 __u8 m_i_fsize; /* Fragment size */
317 __u32 m_i_reserved2[2];
319 } osd2; /* OS dependent 2 */
322 #define i_size_high i_dir_acl
324 #if defined(__KERNEL__) || defined(__linux__)
325 #define i_reserved1 osd1.linux1.l_i_reserved1
326 #define i_frag osd2.linux2.l_i_frag
327 #define i_fsize osd2.linux2.l_i_fsize
328 #define i_reserved2 osd2.linux2.l_i_reserved2
332 #define i_translator osd1.hurd1.h_i_translator
333 #define i_frag osd2.hurd2.h_i_frag;
334 #define i_fsize osd2.hurd2.h_i_fsize;
335 #define i_uid_high osd2.hurd2.h_i_uid_high
336 #define i_gid_high osd2.hurd2.h_i_gid_high
337 #define i_author osd2.hurd2.h_i_author
341 #define i_reserved1 osd1.masix1.m_i_reserved1
342 #define i_frag osd2.masix2.m_i_frag
343 #define i_fsize osd2.masix2.m_i_fsize
344 #define i_reserved2 osd2.masix2.m_i_reserved2
350 #define EXT2_VALID_FS 0x0001 /* Unmounted cleanly */
351 #define EXT2_ERROR_FS 0x0002 /* Errors detected */
356 #define EXT2_MOUNT_CHECK_NORMAL 0x0001 /* Do some more checks */
357 #define EXT2_MOUNT_CHECK_STRICT 0x0002 /* Do again more checks */
358 #define EXT2_MOUNT_CHECK (EXT2_MOUNT_CHECK_NORMAL | \
359 EXT2_MOUNT_CHECK_STRICT)
360 #define EXT2_MOUNT_GRPID 0x0004 /* Create files with directory's group */
361 #define EXT2_MOUNT_DEBUG 0x0008 /* Some debugging messages */
362 #define EXT2_MOUNT_ERRORS_CONT 0x0010 /* Continue on errors */
363 #define EXT2_MOUNT_ERRORS_RO 0x0020 /* Remount fs ro on errors */
364 #define EXT2_MOUNT_ERRORS_PANIC 0x0040 /* Panic on errors */
365 #define EXT2_MOUNT_MINIX_DF 0x0080 /* Mimics the Minix statfs */
367 #define clear_opt(o, opt) o &= ~EXT2_MOUNT_##opt
368 #define set_opt(o, opt) o |= EXT2_MOUNT_##opt
369 #define test_opt(sb, opt) ((sb)->u.ext2_sb.s_mount_opt & \
372 * Maximal mount counts between two filesystem checks
374 #define EXT2_DFL_MAX_MNT_COUNT 20 /* Allow 20 mounts */
375 #define EXT2_DFL_CHECKINTERVAL 0 /* Don't use interval check */
378 * Behaviour when detecting errors
380 #define EXT2_ERRORS_CONTINUE 1 /* Continue execution */
381 #define EXT2_ERRORS_RO 2 /* Remount fs read-only */
382 #define EXT2_ERRORS_PANIC 3 /* Panic */
383 #define EXT2_ERRORS_DEFAULT EXT2_ERRORS_CONTINUE
386 * Structure of the super block
388 struct ext2_super_block {
389 __u32 s_inodes_count; /* Inodes count */
390 __u32 s_blocks_count; /* Blocks count */
391 __u32 s_r_blocks_count; /* Reserved blocks count */
392 __u32 s_free_blocks_count; /* Free blocks count */
393 __u32 s_free_inodes_count; /* Free inodes count */
394 __u32 s_first_data_block; /* First Data Block */
395 __u32 s_log_block_size; /* Block size */
396 __s32 s_log_frag_size; /* Fragment size */
397 __u32 s_blocks_per_group; /* # Blocks per group */
398 __u32 s_frags_per_group; /* # Fragments per group */
399 __u32 s_inodes_per_group; /* # Inodes per group */
400 __u32 s_mtime; /* Mount time */
401 __u32 s_wtime; /* Write time */
402 __u16 s_mnt_count; /* Mount count */
403 __s16 s_max_mnt_count; /* Maximal mount count */
404 __u16 s_magic; /* Magic signature */
405 __u16 s_state; /* File system state */
406 __u16 s_errors; /* Behaviour when detecting errors */
407 __u16 s_minor_rev_level; /* minor revision level */
408 __u32 s_lastcheck; /* time of last check */
409 __u32 s_checkinterval; /* max. time between checks */
410 __u32 s_creator_os; /* OS */
411 __u32 s_rev_level; /* Revision level */
412 __u16 s_def_resuid; /* Default uid for reserved blocks */
413 __u16 s_def_resgid; /* Default gid for reserved blocks */
415 * These fields are for EXT2_DYNAMIC_REV superblocks only.
417 * Note: the difference between the compatible feature set and
418 * the incompatible feature set is that if there is a bit set
419 * in the incompatible feature set that the kernel doesn't
420 * know about, it should refuse to mount the filesystem.
422 * e2fsck's requirements are more strict; if it doesn't know
423 * about a feature in either the compatible or incompatible
424 * feature set, it must abort and not try to meddle with
425 * things it doesn't understand...
427 __u32 s_first_ino; /* First non-reserved inode */
428 __u16 s_inode_size; /* size of inode structure */
429 __u16 s_block_group_nr; /* block group # of this superblock */
430 __u32 s_feature_compat; /* compatible feature set */
431 __u32 s_feature_incompat; /* incompatible feature set */
432 __u32 s_feature_ro_compat; /* readonly-compatible feature set */
433 __u8 s_uuid[16]; /* 128-bit uuid for volume */
434 char s_volume_name[16]; /* volume name */
435 char s_last_mounted[64]; /* directory where last mounted */
436 __u32 s_algorithm_usage_bitmap; /* For compression */
438 * Performance hints. Directory preallocation should only
439 * happen if the EXT2_COMPAT_PREALLOC flag is on.
441 __u8 s_prealloc_blocks; /* Nr of blocks to try to preallocate*/
442 __u8 s_prealloc_dir_blocks; /* Nr to preallocate for dirs */
444 __u32 s_reserved[204]; /* Padding to the end of the block */
448 #define EXT2_SB(sb) (&((sb)->u.ext2_sb))
450 /* Assume that user mode programs are passing in an ext2fs superblock, not
451 * a kernel struct super_block. This will allow us to call the feature-test
452 * macros from user land. */
453 #define EXT2_SB(sb) (sb)
457 * Codes for operating systems
459 #define EXT2_OS_LINUX 0
460 #define EXT2_OS_HURD 1
461 #define EXT2_OS_MASIX 2
462 #define EXT2_OS_FREEBSD 3
463 #define EXT2_OS_LITES 4
468 #define EXT2_GOOD_OLD_REV 0 /* The good old (original) format */
469 #define EXT2_DYNAMIC_REV 1 /* V2 format w/ dynamic inode sizes */
471 #define EXT2_CURRENT_REV EXT2_GOOD_OLD_REV
472 #define EXT2_MAX_SUPP_REV EXT2_DYNAMIC_REV
474 #define EXT2_GOOD_OLD_INODE_SIZE 128
477 * Feature set definitions
480 #define EXT2_HAS_COMPAT_FEATURE(sb,mask) \
481 ( EXT2_SB(sb)->s_feature_compat & (mask) )
482 #define EXT2_HAS_RO_COMPAT_FEATURE(sb,mask) \
483 ( EXT2_SB(sb)->s_feature_ro_compat & (mask) )
484 #define EXT2_HAS_INCOMPAT_FEATURE(sb,mask) \
485 ( EXT2_SB(sb)->s_feature_incompat & (mask) )
487 #define EXT2_FEATURE_COMPAT_DIR_PREALLOC 0x0001
489 #define EXT2_FEATURE_RO_COMPAT_SPARSE_SUPER 0x0001
490 #define EXT2_FEATURE_RO_COMPAT_LARGE_FILE 0x0002
491 #define EXT2_FEATURE_RO_COMPAT_BTREE_DIR 0x0004
493 #define EXT2_FEATURE_INCOMPAT_COMPRESSION 0x0001
494 #define EXT2_FEATURE_INCOMPAT_FILETYPE 0x0002
496 #define EXT2_FEATURE_COMPAT_SUPP 0
497 #define EXT2_FEATURE_INCOMPAT_SUPP EXT2_FEATURE_INCOMPAT_FILETYPE
499 #define EXT2_FEATURE_RO_COMPAT_SUPP (EXT2_FEATURE_RO_COMPAT_SPARSE_SUPER| \
500 EXT2_FEATURE_RO_COMPAT_LARGE_FILE| \
501 EXT2_FEATURE_RO_COMPAT_BTREE_DIR)
503 #define EXT2_FEATURE_RO_COMPAT_SUPP (EXT2_FEATURE_RO_COMPAT_SPARSE_SUPER| \
504 EXT2_FEATURE_RO_COMPAT_LARGE_FILE)
508 * Default values for user and/or group using reserved blocks
510 #define EXT2_DEF_RESUID 0
511 #define EXT2_DEF_RESGID 0
514 * Structure of a directory entry
516 #define EXT2_NAME_LEN 255
518 struct ext2_dir_entry {
519 __u32 inode; /* Inode number */
520 __u16 rec_len; /* Directory entry length */
521 __u16 name_len; /* Name length */
522 char name[EXT2_NAME_LEN]; /* File name */
526 * The new version of the directory entry. Since EXT2 structures are
527 * stored in intel byte order, and the name_len field could never be
528 * bigger than 255 chars, it's safe to reclaim the extra byte for the
531 struct ext2_dir_entry_2 {
532 __u32 inode; /* Inode number */
533 __u16 rec_len; /* Directory entry length */
534 __u8 name_len; /* Name length */
536 char name[EXT2_NAME_LEN]; /* File name */
540 * Ext2 directory file types. Only the low 3 bits are used. The
541 * other bits are reserved for now.
543 #define EXT2_FT_UNKNOWN 0
544 #define EXT2_FT_REG_FILE 1
545 #define EXT2_FT_DIR 2
546 #define EXT2_FT_CHRDEV 3
547 #define EXT2_FT_BLKDEV 4
548 #define EXT2_FT_FIFO 5
549 #define EXT2_FT_SOCK 6
550 #define EXT2_FT_SYMLINK 7
552 #define EXT2_FT_MAX 8
555 * EXT2_DIR_PAD defines the directory entries boundaries
557 * NOTE: It must be a multiple of 4
559 #define EXT2_DIR_PAD 4
560 #define EXT2_DIR_ROUND (EXT2_DIR_PAD - 1)
561 #define EXT2_DIR_REC_LEN(name_len) (((name_len) + 8 + EXT2_DIR_ROUND) & \
564 #endif /* _LINUX_EXT2_FS_H */