jcs.org
Serenity Operating System
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
19static constexpr size_t max_block_size = 4096;
20
21#include "ext2_types.h" /* Changed from linux/types.h */
22
23/*
24 * The second extended filesystem constants/structures
25 */
26
27/*
28 * Define EXT2_PREALLOCATE to preallocate data blocks for expanding files
29 */
30#define EXT2_PREALLOCATE
31#define EXT2_DEFAULT_PREALLOC_BLOCKS 8
32
33/*
34 * The second extended file system version
35 */
36#define EXT2FS_DATE "95/08/09"
37#define EXT2FS_VERSION "0.5b"
38
39/*
40 * Special inode numbers
41 */
42#define EXT2_BAD_INO 1 /* Bad blocks inode */
43#define EXT2_ROOT_INO 2 /* Root inode */
44#define EXT2_ACL_IDX_INO 3 /* ACL inode */
45#define EXT2_ACL_DATA_INO 4 /* ACL inode */
46#define EXT2_BOOT_LOADER_INO 5 /* Boot loader inode */
47#define EXT2_UNDEL_DIR_INO 6 /* Undelete directory inode */
48#define EXT2_RESIZE_INO 7 /* Reserved group descriptors inode */
49#define EXT2_JOURNAL_INO 8 /* Journal inode */
50
51/* First non-reserved inode for old ext2 filesystems */
52#define EXT2_GOOD_OLD_FIRST_INO 11
53
54/*
55 * The second extended file system magic number
56 */
57#define EXT2_SUPER_MAGIC 0xEF53
58
59#ifdef __KERNEL__
60# define EXT2_SB(sb) (&((sb)->u.ext2_sb))
61#else
62/* Assume that user mode programs are passing in an ext2fs superblock, not
63 * a kernel struct super_block. This will allow us to call the feature-test
64 * macros from user land. */
65# define EXT2_SB(sb) (sb)
66#endif
67
68/*
69 * Maximal count of links to a file
70 */
71#define EXT2_LINK_MAX 65000
72
73/*
74 * Macro-instructions used to manage several block sizes
75 */
76#define EXT2_MIN_BLOCK_LOG_SIZE 10 /* 1024 */
77#define EXT2_MAX_BLOCK_LOG_SIZE 16 /* 65536 */
78#define EXT2_MIN_BLOCK_SIZE (1 << EXT2_MIN_BLOCK_LOG_SIZE)
79#define EXT2_MAX_BLOCK_SIZE (1 << EXT2_MAX_BLOCK_LOG_SIZE)
80#ifdef __KERNEL__
81# define EXT2_BLOCK_SIZE(s) ((s)->s_blocksize)
82# define EXT2_BLOCK_SIZE_BITS(s) ((s)->s_blocksize_bits)
83# define EXT2_ADDR_PER_BLOCK_BITS(s) (EXT2_SB(s)->addr_per_block_bits)
84# define EXT2_INODE_SIZE(s) (EXT2_SB(s)->s_inode_size)
85# define EXT2_FIRST_INO(s) (EXT2_SB(s)->s_first_ino)
86#else
87# define EXT2_BLOCK_SIZE(s) (EXT2_MIN_BLOCK_SIZE << (s)->s_log_block_size)
88# define EXT2_BLOCK_SIZE_BITS(s) ((s)->s_log_block_size + 10)
89# define EXT2_INODE_SIZE(s) (((s)->s_rev_level == EXT2_GOOD_OLD_REV) ? EXT2_GOOD_OLD_INODE_SIZE : (s)->s_inode_size)
90# define EXT2_FIRST_INO(s) (((s)->s_rev_level == EXT2_GOOD_OLD_REV) ? EXT2_GOOD_OLD_FIRST_INO : (s)->s_first_ino)
91#endif
92#define EXT2_ADDR_PER_BLOCK(s) (EXT2_BLOCK_SIZE(s) / sizeof(__u32))
93
94/*
95 * Macro-instructions used to manage fragments
96 */
97#define EXT2_MIN_FRAG_SIZE EXT2_MIN_BLOCK_SIZE
98#define EXT2_MAX_FRAG_SIZE EXT2_MAX_BLOCK_SIZE
99#define EXT2_MIN_FRAG_LOG_SIZE EXT2_MIN_BLOCK_LOG_SIZE
100#ifdef __KERNEL__
101# define EXT2_FRAG_SIZE(s) (EXT2_SB(s)->s_frag_size)
102# define EXT2_FRAGS_PER_BLOCK(s) (EXT2_SB(s)->s_frags_per_block)
103#else
104# define EXT2_FRAG_SIZE(s) (EXT2_MIN_FRAG_SIZE << (s)->s_log_frag_size)
105# define EXT2_FRAGS_PER_BLOCK(s) (EXT2_BLOCK_SIZE(s) / EXT2_FRAG_SIZE(s))
106#endif
107
108/*
109 * ACL structures
110 */
111struct ext2_acl_header /* Header of Access Control Lists */
112{
113 __u32 aclh_size;
114 __u32 aclh_file_count;
115 __u32 aclh_acle_count;
116 __u32 aclh_first_acle;
117};
118
119struct ext2_acl_entry /* Access Control List Entry */
120{
121 __u32 acle_size;
122 __u16 acle_perms; /* Access permissions */
123 __u16 acle_type; /* Type of entry */
124 __u16 acle_tag; /* User or group identity */
125 __u16 acle_pad1;
126 __u32 acle_next; /* Pointer on next entry for the */
127 /* same inode or on next free entry */
128};
129
130/*
131 * Structure of a blocks group descriptor
132 */
133struct ext2_group_desc {
134 __u32 bg_block_bitmap; /* Blocks bitmap block */
135 __u32 bg_inode_bitmap; /* Inodes bitmap block */
136 __u32 bg_inode_table; /* Inodes table block */
137 __u16 bg_free_blocks_count; /* Free blocks count */
138 __u16 bg_free_inodes_count; /* Free inodes count */
139 __u16 bg_used_dirs_count; /* Directories count */
140 __u16 bg_flags;
141 __u32 bg_reserved[2];
142 __u16 bg_itable_unused; /* Unused inodes count */
143 __u16 bg_checksum; /* crc16(s_uuid+group_num+group_desc)*/
144};
145
146struct ext4_group_desc {
147 __u32 bg_block_bitmap; /* Blocks bitmap block */
148 __u32 bg_inode_bitmap; /* Inodes bitmap block */
149 __u32 bg_inode_table; /* Inodes table block */
150 __u16 bg_free_blocks_count; /* Free blocks count */
151 __u16 bg_free_inodes_count; /* Free inodes count */
152 __u16 bg_used_dirs_count; /* Directories count */
153 __u16 bg_flags;
154 __u32 bg_reserved[2];
155 __u16 bg_itable_unused; /* Unused inodes count */
156 __u16 bg_checksum; /* crc16(s_uuid+group_num+group_desc)*/
157 __u32 bg_block_bitmap_hi; /* Blocks bitmap block MSB */
158 __u32 bg_inode_bitmap_hi; /* Inodes bitmap block MSB */
159 __u32 bg_inode_table_hi; /* Inodes table block MSB */
160 __u16 bg_free_blocks_count_hi; /* Free blocks count MSB */
161 __u16 bg_free_inodes_count_hi; /* Free inodes count MSB */
162 __u16 bg_used_dirs_count_hi; /* Directories count MSB */
163 __u16 bg_pad;
164 __u32 bg_reserved2[3];
165};
166
167#define EXT2_BG_INODE_UNINIT 0x0001 /* Inode table/bitmap not initialized */
168#define EXT2_BG_BLOCK_UNINIT 0x0002 /* Block bitmap not initialized */
169#define EXT2_BG_INODE_ZEROED 0x0004 /* On-disk itable initialized to zero */
170
171/*
172 * Data structures used by the directory indexing feature
173 *
174 * Note: all of the multibyte integer fields are little endian.
175 */
176
177/*
178 * Note: dx_root_info is laid out so that if it should somehow get
179 * overlaid by a dirent the two low bits of the hash version will be
180 * zero. Therefore, the hash version mod 4 should never be 0.
181 * Sincerely, the paranoia department.
182 */
183struct ext2_dx_root_info {
184 __u32 reserved_zero;
185 __u8 hash_version; /* 0 now, 1 at release */
186 __u8 info_length; /* 8 */
187 __u8 indirect_levels;
188 __u8 unused_flags;
189};
190
191#define EXT2_HASH_LEGACY 0
192#define EXT2_HASH_HALF_MD4 1
193#define EXT2_HASH_TEA 2
194#define EXT2_HASH_LEGACY_UNSIGNED 3 /* reserved for userspace lib */
195#define EXT2_HASH_HALF_MD4_UNSIGNED 4 /* reserved for userspace lib */
196#define EXT2_HASH_TEA_UNSIGNED 5 /* reserved for userspace lib */
197
198#define EXT2_HASH_FLAG_INCOMPAT 0x1
199
200struct ext2_dx_entry {
201 __u32 hash;
202 __u32 block;
203};
204
205struct ext2_dx_countlimit {
206 __u16 limit;
207 __u16 count;
208};
209
210/*
211 * Macro-instructions used to manage group descriptors
212 */
213#define EXT2_MIN_DESC_SIZE 32
214#define EXT2_MIN_DESC_SIZE_64BIT 64
215#define EXT2_MAX_DESC_SIZE EXT2_MIN_BLOCK_SIZE
216#define EXT2_DESC_SIZE(s) \
217 ((EXT2_SB(s)->s_feature_incompat & EXT4_FEATURE_INCOMPAT_64BIT) ? (s)->s_desc_size : EXT2_MIN_DESC_SIZE)
218
219#define EXT2_BLOCKS_PER_GROUP(s) (EXT2_SB(s)->s_blocks_per_group)
220#define EXT2_INODES_PER_GROUP(s) (EXT2_SB(s)->s_inodes_per_group)
221#define EXT2_INODES_PER_BLOCK(s) (EXT2_BLOCK_SIZE(s) / EXT2_INODE_SIZE(s))
222/* limits imposed by 16-bit value gd_free_{blocks,inode}_count */
223#define EXT2_MAX_BLOCKS_PER_GROUP(s) ((1 << 16) - 8)
224#define EXT2_MAX_INODES_PER_GROUP(s) ((1 << 16) - EXT2_INODES_PER_BLOCK(s))
225#ifdef __KERNEL__
226# define EXT2_DESC_PER_BLOCK(s) (EXT2_SB(s)->s_desc_per_block)
227# define EXT2_DESC_PER_BLOCK_BITS(s) (EXT2_SB(s)->s_desc_per_block_bits)
228#else
229# define EXT2_DESC_PER_BLOCK(s) (EXT2_BLOCK_SIZE(s) / EXT2_DESC_SIZE(s))
230#endif
231
232/*
233 * Constants relative to the data blocks
234 */
235#define EXT2_NDIR_BLOCKS 12
236#define EXT2_IND_BLOCK EXT2_NDIR_BLOCKS
237#define EXT2_DIND_BLOCK (EXT2_IND_BLOCK + 1)
238#define EXT2_TIND_BLOCK (EXT2_DIND_BLOCK + 1)
239#define EXT2_N_BLOCKS (EXT2_TIND_BLOCK + 1)
240
241/*
242 * Inode flags
243 */
244#define EXT2_SECRM_FL 0x00000001 /* Secure deletion */
245#define EXT2_UNRM_FL 0x00000002 /* Undelete */
246#define EXT2_COMPR_FL 0x00000004 /* Compress file */
247#define EXT2_SYNC_FL 0x00000008 /* Synchronous updates */
248#define EXT2_IMMUTABLE_FL 0x00000010 /* Immutable file */
249#define EXT2_APPEND_FL 0x00000020 /* writes to file may only append */
250#define EXT2_NODUMP_FL 0x00000040 /* do not dump file */
251#define EXT2_NOATIME_FL 0x00000080 /* do not update atime */
252/* Reserved for compression usage... */
253#define EXT2_DIRTY_FL 0x00000100
254#define EXT2_COMPRBLK_FL 0x00000200 /* One or more compressed clusters */
255#define EXT2_NOCOMPR_FL 0x00000400 /* Access raw compressed data */
256#define EXT2_ECOMPR_FL 0x00000800 /* Compression error */
257/* End compression flags --- maybe not all used */
258#define EXT2_BTREE_FL 0x00001000 /* btree format dir */
259#define EXT2_INDEX_FL 0x00001000 /* hash-indexed directory */
260#define EXT2_IMAGIC_FL 0x00002000
261#define EXT3_JOURNAL_DATA_FL 0x00004000 /* file data should be journaled */
262#define EXT2_NOTAIL_FL 0x00008000 /* file tail should not be merged */
263#define EXT2_DIRSYNC_FL 0x00010000 /* Synchronous directory modifications */
264#define EXT2_TOPDIR_FL 0x00020000 /* Top of directory hierarchies*/
265#define EXT4_HUGE_FILE_FL 0x00040000 /* Set to each huge file */
266#define EXT4_EXTENTS_FL 0x00080000 /* Inode uses extents */
267#define EXT2_RESERVED_FL 0x80000000 /* reserved for ext2 lib */
268
269#define EXT2_FL_USER_VISIBLE 0x000BDFFF /* User visible flags */
270#define EXT2_FL_USER_MODIFIABLE 0x000080FF /* User modifiable flags */
271
272/*
273 * ioctl commands
274 */
275
276/* Used for online resize */
277struct ext2_new_group_input {
278 __u32 group; /* Group number for this data */
279 __u32 block_bitmap; /* Absolute block number of block bitmap */
280 __u32 inode_bitmap; /* Absolute block number of inode bitmap */
281 __u32 inode_table; /* Absolute block number of inode table start */
282 __u32 blocks_count; /* Total number of blocks in this group */
283 __u16 reserved_blocks; /* Number of reserved blocks in this group */
284 __u16 unused; /* Number of reserved GDT blocks in group */
285};
286
287struct ext4_new_group_input {
288 __u32 group; /* Group number for this data */
289 __u64 block_bitmap; /* Absolute block number of block bitmap */
290 __u64 inode_bitmap; /* Absolute block number of inode bitmap */
291 __u64 inode_table; /* Absolute block number of inode table start */
292 __u32 blocks_count; /* Total number of blocks in this group */
293 __u16 reserved_blocks; /* Number of reserved blocks in this group */
294 __u16 unused;
295};
296
297#ifdef __GNU__ /* Needed for the Hurd */
298# define _IOT_ext2_new_group_input _IOT(_IOTS(__u32), 5, _IOTS(__u16), 2, 0, 0)
299#endif
300
301#define EXT2_IOC_GETFLAGS _IOR('f', 1, long)
302#define EXT2_IOC_SETFLAGS _IOW('f', 2, long)
303#define EXT2_IOC_GETVERSION _IOR('v', 1, long)
304#define EXT2_IOC_SETVERSION _IOW('v', 2, long)
305#define EXT2_IOC_GETVERSION_NEW _IOR('f', 3, long)
306#define EXT2_IOC_SETVERSION_NEW _IOW('f', 4, long)
307#define EXT2_IOC_GROUP_EXTEND _IOW('f', 7, unsigned long)
308#define EXT2_IOC_GROUP_ADD _IOW('f', 8, struct ext2_new_group_input)
309#define EXT4_IOC_GROUP_ADD _IOW('f', 8, struct ext4_new_group_input)
310
311/*
312 * Structure of an inode on the disk
313 */
314struct ext2_inode {
315 __u16 i_mode; /* File mode */
316 __u16 i_uid; /* Low 16 bits of Owner Uid */
317 __u32 i_size; /* Size in bytes */
318 __u32 i_atime; /* Access time */
319 __u32 i_ctime; /* Inode change time */
320 __u32 i_mtime; /* Modification time */
321 __u32 i_dtime; /* Deletion Time */
322 __u16 i_gid; /* Low 16 bits of Group Id */
323 __u16 i_links_count; /* Links count */
324 __u32 i_blocks; /* Blocks count */
325 __u32 i_flags; /* File flags */
326 union {
327 struct {
328 __u32 l_i_version; /* was l_i_reserved1 */
329 } linux1;
330 struct {
331 __u32 h_i_translator;
332 } hurd1;
333 } osd1; /* OS dependent 1 */
334 __u32 i_block[EXT2_N_BLOCKS]; /* Pointers to blocks */
335 __u32 i_generation; /* File version (for NFS) */
336 __u32 i_file_acl; /* File ACL */
337 __u32 i_dir_acl; /* Directory ACL */
338 __u32 i_faddr; /* Fragment address */
339 union {
340 struct {
341 __u16 l_i_blocks_hi;
342 __u16 l_i_file_acl_high;
343 __u16 l_i_uid_high; /* these 2 fields */
344 __u16 l_i_gid_high; /* were reserved2[0] */
345 __u32 l_i_reserved2;
346 } linux2;
347 struct {
348 __u8 h_i_frag; /* Fragment number */
349 __u8 h_i_fsize; /* Fragment size */
350 __u16 h_i_mode_high;
351 __u16 h_i_uid_high;
352 __u16 h_i_gid_high;
353 __u32 h_i_author;
354 } hurd2;
355 } osd2; /* OS dependent 2 */
356};
357
358/*
359 * Permanent part of an large inode on the disk
360 */
361struct ext2_inode_large {
362 __u16 i_mode; /* File mode */
363 __u16 i_uid; /* Low 16 bits of Owner Uid */
364 __u32 i_size; /* Size in bytes */
365 __u32 i_atime; /* Access time */
366 __u32 i_ctime; /* Inode Change time */
367 __u32 i_mtime; /* Modification time */
368 __u32 i_dtime; /* Deletion Time */
369 __u16 i_gid; /* Low 16 bits of Group Id */
370 __u16 i_links_count; /* Links count */
371 __u32 i_blocks; /* Blocks count */
372 __u32 i_flags; /* File flags */
373 union {
374 struct {
375 __u32 l_i_version; /* was l_i_reserved1 */
376 } linux1;
377 struct {
378 __u32 h_i_translator;
379 } hurd1;
380 } osd1; /* OS dependent 1 */
381 __u32 i_block[EXT2_N_BLOCKS]; /* Pointers to blocks */
382 __u32 i_generation; /* File version (for NFS) */
383 __u32 i_file_acl; /* File ACL */
384 __u32 i_dir_acl; /* Directory ACL */
385 __u32 i_faddr; /* Fragment address */
386 union {
387 struct {
388 __u16 l_i_blocks_hi;
389 __u16 l_i_file_acl_high;
390 __u16 l_i_uid_high; /* these 2 fields */
391 __u16 l_i_gid_high; /* were reserved2[0] */
392 __u32 l_i_reserved2;
393 } linux2;
394 struct {
395 __u8 h_i_frag; /* Fragment number */
396 __u8 h_i_fsize; /* Fragment size */
397 __u16 h_i_mode_high;
398 __u16 h_i_uid_high;
399 __u16 h_i_gid_high;
400 __u32 h_i_author;
401 } hurd2;
402 } osd2; /* OS dependent 2 */
403 __u16 i_extra_isize;
404 __u16 i_pad1;
405 __u32 i_ctime_extra; /* extra Change time (nsec << 2 | epoch) */
406 __u32 i_mtime_extra; /* extra Modification time (nsec << 2 | epoch) */
407 __u32 i_atime_extra; /* extra Access time (nsec << 2 | epoch) */
408 __u32 i_crtime; /* File creation time */
409 __u32 i_crtime_extra; /* extra File creation time (nsec << 2 | epoch)*/
410 __u32 i_version_hi; /* high 32 bits for 64-bit version */
411};
412
413#define i_size_high i_dir_acl
414
415#if defined(__KERNEL__) || defined(__linux__)
416# define i_reserved1 osd1.linux1.l_i_reserved1
417# define i_frag osd2.linux2.l_i_frag
418# define i_fsize osd2.linux2.l_i_fsize
419# define i_uid_low i_uid
420# define i_gid_low i_gid
421# define i_uid_high osd2.linux2.l_i_uid_high
422# define i_gid_high osd2.linux2.l_i_gid_high
423# define i_reserved2 osd2.linux2.l_i_reserved2
424#else
425# if defined(__GNU__)
426
427# define i_translator osd1.hurd1.h_i_translator
428# define i_frag osd2.hurd2.h_i_frag;
429# define i_fsize osd2.hurd2.h_i_fsize;
430# define i_uid_high osd2.hurd2.h_i_uid_high
431# define i_gid_high osd2.hurd2.h_i_gid_high
432# define i_author osd2.hurd2.h_i_author
433
434# endif /* __GNU__ */
435#endif /* defined(__KERNEL__) || defined(__linux__) */
436
437#define inode_uid(inode) ((inode).i_uid | (inode).osd2.linux2.l_i_uid_high << 16)
438#define inode_gid(inode) ((inode).i_gid | (inode).osd2.linux2.l_i_gid_high << 16)
439#define ext2fs_set_i_uid_high(inode, x) ((inode).osd2.linux2.l_i_uid_high = (x))
440#define ext2fs_set_i_gid_high(inode, x) ((inode).osd2.linux2.l_i_gid_high = (x))
441
442/*
443 * File system states
444 */
445#define EXT2_VALID_FS 0x0001 /* Unmounted cleanly */
446#define EXT2_ERROR_FS 0x0002 /* Errors detected */
447#define EXT3_ORPHAN_FS 0x0004 /* Orphans being recovered */
448
449/*
450 * Misc. filesystem flags
451 */
452#define EXT2_FLAGS_SIGNED_HASH 0x0001 /* Signed dirhash in use */
453#define EXT2_FLAGS_UNSIGNED_HASH 0x0002 /* Unsigned dirhash in use */
454#define EXT2_FLAGS_TEST_FILESYS 0x0004 /* OK for use on development code */
455
456/*
457 * Mount flags
458 */
459#define EXT2_MOUNT_CHECK 0x0001 /* Do mount-time checks */
460#define EXT2_MOUNT_GRPID 0x0004 /* Create files with directory's group */
461#define EXT2_MOUNT_DEBUG 0x0008 /* Some debugging messages */
462#define EXT2_MOUNT_ERRORS_CONT 0x0010 /* Continue on errors */
463#define EXT2_MOUNT_ERRORS_RO 0x0020 /* Remount fs ro on errors */
464#define EXT2_MOUNT_ERRORS_PANIC 0x0040 /* Panic on errors */
465#define EXT2_MOUNT_MINIX_DF 0x0080 /* Mimics the Minix statfs */
466#define EXT2_MOUNT_NO_UID32 0x0200 /* Disable 32-bit UIDs */
467
468#define clear_opt(o, opt) o &= ~EXT2_MOUNT_##opt
469#define set_opt(o, opt) o |= EXT2_MOUNT_##opt
470#define test_opt(sb, opt) (EXT2_SB(sb)->s_mount_opt & EXT2_MOUNT_##opt)
471/*
472 * Maximal mount counts between two filesystem checks
473 */
474#define EXT2_DFL_MAX_MNT_COUNT 20 /* Allow 20 mounts */
475#define EXT2_DFL_CHECKINTERVAL 0 /* Don't use interval check */
476
477/*
478 * Behavior when detecting errors
479 */
480#define EXT2_ERRORS_CONTINUE 1 /* Continue execution */
481#define EXT2_ERRORS_RO 2 /* Remount fs read-only */
482#define EXT2_ERRORS_PANIC 3 /* Panic */
483#define EXT2_ERRORS_DEFAULT EXT2_ERRORS_CONTINUE
484
485/*
486 * Structure of the super block
487 */
488struct ext2_super_block {
489 __u32 s_inodes_count; /* Inodes count */
490 __u32 s_blocks_count; /* Blocks count */
491 __u32 s_r_blocks_count; /* Reserved blocks count */
492 __u32 s_free_blocks_count; /* Free blocks count */
493 __u32 s_free_inodes_count; /* Free inodes count */
494 __u32 s_first_data_block; /* First Data Block */
495 __u32 s_log_block_size; /* Block size */
496 __s32 s_log_frag_size; /* Fragment size */
497 __u32 s_blocks_per_group; /* # Blocks per group */
498 __u32 s_frags_per_group; /* # Fragments per group */
499 __u32 s_inodes_per_group; /* # Inodes per group */
500 __u32 s_mtime; /* Mount time */
501 __u32 s_wtime; /* Write time */
502 __u16 s_mnt_count; /* Mount count */
503 __s16 s_max_mnt_count; /* Maximal mount count */
504 __u16 s_magic; /* Magic signature */
505 __u16 s_state; /* File system state */
506 __u16 s_errors; /* Behavior when detecting errors */
507 __u16 s_minor_rev_level; /* minor revision level */
508 __u32 s_lastcheck; /* time of last check */
509 __u32 s_checkinterval; /* max. time between checks */
510 __u32 s_creator_os; /* OS */
511 __u32 s_rev_level; /* Revision level */
512 __u16 s_def_resuid; /* Default uid for reserved blocks */
513 __u16 s_def_resgid; /* Default gid for reserved blocks */
514 /*
515 * These fields are for EXT2_DYNAMIC_REV superblocks only.
516 *
517 * Note: the difference between the compatible feature set and
518 * the incompatible feature set is that if there is a bit set
519 * in the incompatible feature set that the kernel doesn't
520 * know about, it should refuse to mount the filesystem.
521 *
522 * e2fsck's requirements are more strict; if it doesn't know
523 * about a feature in either the compatible or incompatible
524 * feature set, it must abort and not try to meddle with
525 * things it doesn't understand...
526 */
527 __u32 s_first_ino; /* First non-reserved inode */
528 __u16 s_inode_size; /* size of inode structure */
529 __u16 s_block_group_nr; /* block group # of this superblock */
530 __u32 s_feature_compat; /* compatible feature set */
531 __u32 s_feature_incompat; /* incompatible feature set */
532 __u32 s_feature_ro_compat; /* readonly-compatible feature set */
533 __u8 s_uuid[16]; /* 128-bit uuid for volume */
534 char s_volume_name[16]; /* volume name */
535 char s_last_mounted[64]; /* directory where last mounted */
536 __u32 s_algorithm_usage_bitmap; /* For compression */
537 /*
538 * Performance hints. Directory preallocation should only
539 * happen if the EXT2_FEATURE_COMPAT_DIR_PREALLOC flag is on.
540 */
541 __u8 s_prealloc_blocks; /* Nr of blocks to try to preallocate*/
542 __u8 s_prealloc_dir_blocks; /* Nr to preallocate for dirs */
543 __u16 s_reserved_gdt_blocks; /* Per group table for online growth */
544 /*
545 * Journaling support valid if EXT2_FEATURE_COMPAT_HAS_JOURNAL set.
546 */
547 __u8 s_journal_uuid[16]; /* uuid of journal superblock */
548 __u32 s_journal_inum; /* inode number of journal file */
549 __u32 s_journal_dev; /* device number of journal file */
550 __u32 s_last_orphan; /* start of list of inodes to delete */
551 __u32 s_hash_seed[4]; /* HTREE hash seed */
552 __u8 s_def_hash_version; /* Default hash version to use */
553 __u8 s_jnl_backup_type; /* Default type of journal backup */
554 __u16 s_desc_size; /* Group desc. size: INCOMPAT_64BIT */
555 __u32 s_default_mount_opts;
556 __u32 s_first_meta_bg; /* First metablock group */
557 __u32 s_mkfs_time; /* When the filesystem was created */
558 __u32 s_jnl_blocks[17]; /* Backup of the journal inode */
559 __u32 s_blocks_count_hi; /* Blocks count high 32bits */
560 __u32 s_r_blocks_count_hi; /* Reserved blocks count high 32 bits*/
561 __u32 s_free_blocks_hi; /* Free blocks count */
562 __u16 s_min_extra_isize; /* All inodes have at least # bytes */
563 __u16 s_want_extra_isize; /* New inodes should reserve # bytes */
564 __u32 s_flags; /* Miscellaneous flags */
565 __u16 s_raid_stride; /* RAID stride */
566 __u16 s_mmp_interval; /* # seconds to wait in MMP checking */
567 __u64 s_mmp_block; /* Block for multi-mount protection */
568 __u32 s_raid_stripe_width; /* blocks on all data disks (N*stride)*/
569 __u8 s_log_groups_per_flex; /* FLEX_BG group size */
570 __u8 s_reserved_char_pad;
571 __u16 s_reserved_pad; /* Padding to next 32bits */
572 __u32 s_reserved[162]; /* Padding to the end of the block */
573};
574
575/*
576 * Codes for operating systems
577 */
578#define EXT2_OS_LINUX 0
579#define EXT2_OS_HURD 1
580#define EXT2_OBSO_OS_MASIX 2
581#define EXT2_OS_FREEBSD 3
582#define EXT2_OS_LITES 4
583
584/*
585 * Revision levels
586 */
587#define EXT2_GOOD_OLD_REV 0 /* The good old (original) format */
588#define EXT2_DYNAMIC_REV 1 /* V2 format w/ dynamic inode sizes */
589
590#define EXT2_CURRENT_REV EXT2_GOOD_OLD_REV
591#define EXT2_MAX_SUPP_REV EXT2_DYNAMIC_REV
592
593#define EXT2_GOOD_OLD_INODE_SIZE 128
594
595/*
596 * Journal inode backup types
597 */
598#define EXT3_JNL_BACKUP_BLOCKS 1
599
600/*
601 * Feature set definitions
602 */
603
604#define EXT2_HAS_COMPAT_FEATURE(sb, mask) \
605 (EXT2_SB(sb)->s_feature_compat & (mask))
606#define EXT2_HAS_RO_COMPAT_FEATURE(sb, mask) \
607 (EXT2_SB(sb)->s_feature_ro_compat & (mask))
608#define EXT2_HAS_INCOMPAT_FEATURE(sb, mask) \
609 (EXT2_SB(sb)->s_feature_incompat & (mask))
610
611#define EXT2_FEATURE_COMPAT_DIR_PREALLOC 0x0001
612#define EXT2_FEATURE_COMPAT_IMAGIC_INODES 0x0002
613#define EXT3_FEATURE_COMPAT_HAS_JOURNAL 0x0004
614#define EXT2_FEATURE_COMPAT_EXT_ATTR 0x0008
615#define EXT2_FEATURE_COMPAT_RESIZE_INODE 0x0010
616#define EXT2_FEATURE_COMPAT_DIR_INDEX 0x0020
617#define EXT2_FEATURE_COMPAT_LAZY_BG 0x0040
618
619#define EXT2_FEATURE_RO_COMPAT_SPARSE_SUPER 0x0001
620#define EXT2_FEATURE_RO_COMPAT_LARGE_FILE 0x0002
621/* #define EXT2_FEATURE_RO_COMPAT_BTREE_DIR 0x0004 not used */
622#define EXT4_FEATURE_RO_COMPAT_HUGE_FILE 0x0008
623#define EXT4_FEATURE_RO_COMPAT_GDT_CSUM 0x0010
624#define EXT4_FEATURE_RO_COMPAT_DIR_NLINK 0x0020
625#define EXT4_FEATURE_RO_COMPAT_EXTRA_ISIZE 0x0040
626
627#define EXT2_FEATURE_INCOMPAT_COMPRESSION 0x0001
628#define EXT2_FEATURE_INCOMPAT_FILETYPE 0x0002
629#define EXT3_FEATURE_INCOMPAT_RECOVER 0x0004 /* Needs recovery */
630#define EXT3_FEATURE_INCOMPAT_JOURNAL_DEV 0x0008 /* Journal device */
631#define EXT2_FEATURE_INCOMPAT_META_BG 0x0010
632#define EXT3_FEATURE_INCOMPAT_EXTENTS 0x0040
633#define EXT4_FEATURE_INCOMPAT_64BIT 0x0080
634#define EXT4_FEATURE_INCOMPAT_MMP 0x0100
635#define EXT4_FEATURE_INCOMPAT_FLEX_BG 0x0200
636
637#define EXT2_FEATURE_COMPAT_SUPP 0
638#define EXT2_FEATURE_INCOMPAT_SUPP (EXT2_FEATURE_INCOMPAT_FILETYPE)
639#define EXT2_FEATURE_RO_COMPAT_SUPP (EXT2_FEATURE_RO_COMPAT_SPARSE_SUPER | EXT2_FEATURE_RO_COMPAT_LARGE_FILE | EXT4_FEATURE_RO_COMPAT_DIR_NLINK | EXT2_FEATURE_RO_COMPAT_BTREE_DIR)
640
641/*
642 * Default values for user and/or group using reserved blocks
643 */
644#define EXT2_DEF_RESUID 0
645#define EXT2_DEF_RESGID 0
646
647/*
648 * Default mount options
649 */
650#define EXT2_DEFM_DEBUG 0x0001
651#define EXT2_DEFM_BSDGROUPS 0x0002
652#define EXT2_DEFM_XATTR_USER 0x0004
653#define EXT2_DEFM_ACL 0x0008
654#define EXT2_DEFM_UID16 0x0010
655#define EXT3_DEFM_JMODE 0x0060
656#define EXT3_DEFM_JMODE_DATA 0x0020
657#define EXT3_DEFM_JMODE_ORDERED 0x0040
658#define EXT3_DEFM_JMODE_WBACK 0x0060
659
660/*
661 * Structure of a directory entry
662 */
663#define EXT2_NAME_LEN 255
664
665struct ext2_dir_entry {
666 __u32 inode; /* Inode number */
667 __u16 rec_len; /* Directory entry length */
668 __u16 name_len; /* Name length */
669 char name[EXT2_NAME_LEN]; /* Filename */
670};
671
672/*
673 * The new version of the directory entry. Since EXT2 structures are
674 * stored in intel byte order, and the name_len field could never be
675 * bigger than 255 chars, it's safe to reclaim the extra byte for the
676 * file_type field.
677 */
678struct ext2_dir_entry_2 {
679 __u32 inode; /* Inode number */
680 __u16 rec_len; /* Directory entry length */
681 __u8 name_len; /* Name length */
682 __u8 file_type;
683 char name[EXT2_NAME_LEN]; /* Filename */
684};
685
686/*
687 * Ext2 directory file types. Only the low 3 bits are used. The
688 * other bits are reserved for now.
689 */
690#define EXT2_FT_UNKNOWN 0
691#define EXT2_FT_REG_FILE 1
692#define EXT2_FT_DIR 2
693#define EXT2_FT_CHRDEV 3
694#define EXT2_FT_BLKDEV 4
695#define EXT2_FT_FIFO 5
696#define EXT2_FT_SOCK 6
697#define EXT2_FT_SYMLINK 7
698
699#define EXT2_FT_MAX 8
700
701/*
702 * EXT2_DIR_PAD defines the directory entries boundaries
703 *
704 * NOTE: It must be a multiple of 4
705 */
706#define EXT2_DIR_PAD 4
707#define EXT2_DIR_ROUND (EXT2_DIR_PAD - 1)
708#define EXT2_DIR_REC_LEN(name_len) (((name_len) + 8 + EXT2_DIR_ROUND) & ~EXT2_DIR_ROUND)
709
710/*
711 * This structure will be used for multiple mount protection. It will be
712 * written into the block number saved in the s_mmp_block field in the
713 * superblock.
714 */
715#define EXT2_MMP_MAGIC 0x004D4D50 /* ASCII for MMP */
716#define EXT2_MMP_CLEAN 0xFF4D4D50 /* Value of mmp_seq for clean unmount */
717#define EXT2_MMP_FSCK_ON 0xE24D4D50 /* Value of mmp_seq when being fscked */
718
719struct mmp_struct {
720 __u32 mmp_magic;
721 __u32 mmp_seq;
722 __u64 mmp_time;
723 char mmp_nodename[64];
724 char mmp_bdevname[32];
725 __u16 mmp_interval;
726 __u16 mmp_pad1;
727 __u32 mmp_pad2;
728};
729
730/*
731 * Interval in number of seconds to update the MMP sequence number.
732 */
733#define EXT2_MMP_DEF_INTERVAL 5
734
735#endif /* _LINUX_EXT2_FS_H */