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
19#include "ext2_types.h" /* Changed from linux/types.h */
20
21/*
22 * The second extended filesystem constants/structures
23 */
24
25/*
26 * Define EXT2FS_DEBUG to produce debug messages
27 */
28#undef EXT2FS_DEBUG
29
30/*
31 * Define EXT2_PREALLOCATE to preallocate data blocks for expanding files
32 */
33#define EXT2_PREALLOCATE
34#define EXT2_DEFAULT_PREALLOC_BLOCKS 8
35
36/*
37 * The second extended file system version
38 */
39#define EXT2FS_DATE "95/08/09"
40#define EXT2FS_VERSION "0.5b"
41
42/*
43 * Special inode numbers
44 */
45#define EXT2_BAD_INO 1 /* Bad blocks inode */
46#define EXT2_ROOT_INO 2 /* Root inode */
47#define EXT2_ACL_IDX_INO 3 /* ACL inode */
48#define EXT2_ACL_DATA_INO 4 /* ACL inode */
49#define EXT2_BOOT_LOADER_INO 5 /* Boot loader inode */
50#define EXT2_UNDEL_DIR_INO 6 /* Undelete directory inode */
51#define EXT2_RESIZE_INO 7 /* Reserved group descriptors inode */
52#define EXT2_JOURNAL_INO 8 /* Journal inode */
53
54/* First non-reserved inode for old ext2 filesystems */
55#define EXT2_GOOD_OLD_FIRST_INO 11
56
57/*
58 * The second extended file system magic number
59 */
60#define EXT2_SUPER_MAGIC 0xEF53
61
62#ifdef __KERNEL__
63# define EXT2_SB(sb) (&((sb)->u.ext2_sb))
64#else
65/* Assume that user mode programs are passing in an ext2fs superblock, not
66 * a kernel struct super_block. This will allow us to call the feature-test
67 * macros from user land. */
68# define EXT2_SB(sb) (sb)
69#endif
70
71/*
72 * Maximal count of links to a file
73 */
74#define EXT2_LINK_MAX 65000
75
76/*
77 * Macro-instructions used to manage several block sizes
78 */
79#define EXT2_MIN_BLOCK_LOG_SIZE 10 /* 1024 */
80#define EXT2_MAX_BLOCK_LOG_SIZE 16 /* 65536 */
81#define EXT2_MIN_BLOCK_SIZE (1 << EXT2_MIN_BLOCK_LOG_SIZE)
82#define EXT2_MAX_BLOCK_SIZE (1 << EXT2_MAX_BLOCK_LOG_SIZE)
83#ifdef __KERNEL__
84# define EXT2_BLOCK_SIZE(s) ((s)->s_blocksize)
85# define EXT2_BLOCK_SIZE_BITS(s) ((s)->s_blocksize_bits)
86# define EXT2_ADDR_PER_BLOCK_BITS(s) (EXT2_SB(s)->addr_per_block_bits)
87# define EXT2_INODE_SIZE(s) (EXT2_SB(s)->s_inode_size)
88# define EXT2_FIRST_INO(s) (EXT2_SB(s)->s_first_ino)
89#else
90# define EXT2_BLOCK_SIZE(s) (EXT2_MIN_BLOCK_SIZE << (s)->s_log_block_size)
91# define EXT2_BLOCK_SIZE_BITS(s) ((s)->s_log_block_size + 10)
92# define EXT2_INODE_SIZE(s) (((s)->s_rev_level == EXT2_GOOD_OLD_REV) ? EXT2_GOOD_OLD_INODE_SIZE : (s)->s_inode_size)
93# define EXT2_FIRST_INO(s) (((s)->s_rev_level == EXT2_GOOD_OLD_REV) ? EXT2_GOOD_OLD_FIRST_INO : (s)->s_first_ino)
94#endif
95#define EXT2_ADDR_PER_BLOCK(s) (EXT2_BLOCK_SIZE(s) / sizeof(__u32))
96
97/*
98 * Macro-instructions used to manage fragments
99 */
100#define EXT2_MIN_FRAG_SIZE EXT2_MIN_BLOCK_SIZE
101#define EXT2_MAX_FRAG_SIZE EXT2_MAX_BLOCK_SIZE
102#define EXT2_MIN_FRAG_LOG_SIZE EXT2_MIN_BLOCK_LOG_SIZE
103#ifdef __KERNEL__
104# define EXT2_FRAG_SIZE(s) (EXT2_SB(s)->s_frag_size)
105# define EXT2_FRAGS_PER_BLOCK(s) (EXT2_SB(s)->s_frags_per_block)
106#else
107# define EXT2_FRAG_SIZE(s) (EXT2_MIN_FRAG_SIZE << (s)->s_log_frag_size)
108# define EXT2_FRAGS_PER_BLOCK(s) (EXT2_BLOCK_SIZE(s) / EXT2_FRAG_SIZE(s))
109#endif
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 __u32 bg_block_bitmap; /* Blocks bitmap block */
138 __u32 bg_inode_bitmap; /* Inodes bitmap block */
139 __u32 bg_inode_table; /* Inodes table block */
140 __u16 bg_free_blocks_count; /* Free blocks count */
141 __u16 bg_free_inodes_count; /* Free inodes count */
142 __u16 bg_used_dirs_count; /* Directories count */
143 __u16 bg_flags;
144 __u32 bg_reserved[2];
145 __u16 bg_itable_unused; /* Unused inodes count */
146 __u16 bg_checksum; /* crc16(s_uuid+grouo_num+group_desc)*/
147};
148
149struct ext4_group_desc {
150 __u32 bg_block_bitmap; /* Blocks bitmap block */
151 __u32 bg_inode_bitmap; /* Inodes bitmap block */
152 __u32 bg_inode_table; /* Inodes table block */
153 __u16 bg_free_blocks_count; /* Free blocks count */
154 __u16 bg_free_inodes_count; /* Free inodes count */
155 __u16 bg_used_dirs_count; /* Directories count */
156 __u16 bg_flags;
157 __u32 bg_reserved[2];
158 __u16 bg_itable_unused; /* Unused inodes count */
159 __u16 bg_checksum; /* crc16(s_uuid+grouo_num+group_desc)*/
160 __u32 bg_block_bitmap_hi; /* Blocks bitmap block MSB */
161 __u32 bg_inode_bitmap_hi; /* Inodes bitmap block MSB */
162 __u32 bg_inode_table_hi; /* Inodes table block MSB */
163 __u16 bg_free_blocks_count_hi; /* Free blocks count MSB */
164 __u16 bg_free_inodes_count_hi; /* Free inodes count MSB */
165 __u16 bg_used_dirs_count_hi; /* Directories count MSB */
166 __u16 bg_pad;
167 __u32 bg_reserved2[3];
168};
169
170#define EXT2_BG_INODE_UNINIT 0x0001 /* Inode table/bitmap not initialized */
171#define EXT2_BG_BLOCK_UNINIT 0x0002 /* Block bitmap not initialized */
172#define EXT2_BG_INODE_ZEROED 0x0004 /* On-disk itable initialized to zero */
173
174/*
175 * Data structures used by the directory indexing feature
176 *
177 * Note: all of the multibyte integer fields are little endian.
178 */
179
180/*
181 * Note: dx_root_info is laid out so that if it should somehow get
182 * overlaid by a dirent the two low bits of the hash version will be
183 * zero. Therefore, the hash version mod 4 should never be 0.
184 * Sincerely, the paranoia department.
185 */
186struct ext2_dx_root_info {
187 __u32 reserved_zero;
188 __u8 hash_version; /* 0 now, 1 at release */
189 __u8 info_length; /* 8 */
190 __u8 indirect_levels;
191 __u8 unused_flags;
192};
193
194#define EXT2_HASH_LEGACY 0
195#define EXT2_HASH_HALF_MD4 1
196#define EXT2_HASH_TEA 2
197#define EXT2_HASH_LEGACY_UNSIGNED 3 /* reserved for userspace lib */
198#define EXT2_HASH_HALF_MD4_UNSIGNED 4 /* reserved for userspace lib */
199#define EXT2_HASH_TEA_UNSIGNED 5 /* reserved for userspace lib */
200
201#define EXT2_HASH_FLAG_INCOMPAT 0x1
202
203struct ext2_dx_entry {
204 __u32 hash;
205 __u32 block;
206};
207
208struct ext2_dx_countlimit {
209 __u16 limit;
210 __u16 count;
211};
212
213/*
214 * Macro-instructions used to manage group descriptors
215 */
216#define EXT2_MIN_DESC_SIZE 32
217#define EXT2_MIN_DESC_SIZE_64BIT 64
218#define EXT2_MAX_DESC_SIZE EXT2_MIN_BLOCK_SIZE
219#define EXT2_DESC_SIZE(s) \
220 ((EXT2_SB(s)->s_feature_incompat & EXT4_FEATURE_INCOMPAT_64BIT) ? (s)->s_desc_size : EXT2_MIN_DESC_SIZE)
221
222#define EXT2_BLOCKS_PER_GROUP(s) (EXT2_SB(s)->s_blocks_per_group)
223#define EXT2_INODES_PER_GROUP(s) (EXT2_SB(s)->s_inodes_per_group)
224#define EXT2_INODES_PER_BLOCK(s) (EXT2_BLOCK_SIZE(s) / EXT2_INODE_SIZE(s))
225/* limits imposed by 16-bit value gd_free_{blocks,inode}_count */
226#define EXT2_MAX_BLOCKS_PER_GROUP(s) ((1 << 16) - 8)
227#define EXT2_MAX_INODES_PER_GROUP(s) ((1 << 16) - EXT2_INODES_PER_BLOCK(s))
228#ifdef __KERNEL__
229# define EXT2_DESC_PER_BLOCK(s) (EXT2_SB(s)->s_desc_per_block)
230# define EXT2_DESC_PER_BLOCK_BITS(s) (EXT2_SB(s)->s_desc_per_block_bits)
231#else
232# define EXT2_DESC_PER_BLOCK(s) (EXT2_BLOCK_SIZE(s) / EXT2_DESC_SIZE(s))
233#endif
234
235/*
236 * Constants relative to the data blocks
237 */
238#define EXT2_NDIR_BLOCKS 12
239#define EXT2_IND_BLOCK EXT2_NDIR_BLOCKS
240#define EXT2_DIND_BLOCK (EXT2_IND_BLOCK + 1)
241#define EXT2_TIND_BLOCK (EXT2_DIND_BLOCK + 1)
242#define EXT2_N_BLOCKS (EXT2_TIND_BLOCK + 1)
243
244/*
245 * Inode flags
246 */
247#define EXT2_SECRM_FL 0x00000001 /* Secure deletion */
248#define EXT2_UNRM_FL 0x00000002 /* Undelete */
249#define EXT2_COMPR_FL 0x00000004 /* Compress file */
250#define EXT2_SYNC_FL 0x00000008 /* Synchronous updates */
251#define EXT2_IMMUTABLE_FL 0x00000010 /* Immutable file */
252#define EXT2_APPEND_FL 0x00000020 /* writes to file may only append */
253#define EXT2_NODUMP_FL 0x00000040 /* do not dump file */
254#define EXT2_NOATIME_FL 0x00000080 /* do not update atime */
255/* Reserved for compression usage... */
256#define EXT2_DIRTY_FL 0x00000100
257#define EXT2_COMPRBLK_FL 0x00000200 /* One or more compressed clusters */
258#define EXT2_NOCOMPR_FL 0x00000400 /* Access raw compressed data */
259#define EXT2_ECOMPR_FL 0x00000800 /* Compression error */
260/* End compression flags --- maybe not all used */
261#define EXT2_BTREE_FL 0x00001000 /* btree format dir */
262#define EXT2_INDEX_FL 0x00001000 /* hash-indexed directory */
263#define EXT2_IMAGIC_FL 0x00002000
264#define EXT3_JOURNAL_DATA_FL 0x00004000 /* file data should be journaled */
265#define EXT2_NOTAIL_FL 0x00008000 /* file tail should not be merged */
266#define EXT2_DIRSYNC_FL 0x00010000 /* Synchronous directory modifications */
267#define EXT2_TOPDIR_FL 0x00020000 /* Top of directory hierarchies*/
268#define EXT4_HUGE_FILE_FL 0x00040000 /* Set to each huge file */
269#define EXT4_EXTENTS_FL 0x00080000 /* Inode uses extents */
270#define EXT2_RESERVED_FL 0x80000000 /* reserved for ext2 lib */
271
272#define EXT2_FL_USER_VISIBLE 0x000BDFFF /* User visible flags */
273#define EXT2_FL_USER_MODIFIABLE 0x000080FF /* User modifiable flags */
274
275/*
276 * ioctl commands
277 */
278
279/* Used for online resize */
280struct ext2_new_group_input {
281 __u32 group; /* Group number for this data */
282 __u32 block_bitmap; /* Absolute block number of block bitmap */
283 __u32 inode_bitmap; /* Absolute block number of inode bitmap */
284 __u32 inode_table; /* Absolute block number of inode table start */
285 __u32 blocks_count; /* Total number of blocks in this group */
286 __u16 reserved_blocks; /* Number of reserved blocks in this group */
287 __u16 unused; /* Number of reserved GDT blocks in group */
288};
289
290struct ext4_new_group_input {
291 __u32 group; /* Group number for this data */
292 __u64 block_bitmap; /* Absolute block number of block bitmap */
293 __u64 inode_bitmap; /* Absolute block number of inode bitmap */
294 __u64 inode_table; /* Absolute block number of inode table start */
295 __u32 blocks_count; /* Total number of blocks in this group */
296 __u16 reserved_blocks; /* Number of reserved blocks in this group */
297 __u16 unused;
298};
299
300#ifdef __GNU__ /* Needed for the Hurd */
301# define _IOT_ext2_new_group_input _IOT(_IOTS(__u32), 5, _IOTS(__u16), 2, 0, 0)
302#endif
303
304#define EXT2_IOC_GETFLAGS _IOR('f', 1, long)
305#define EXT2_IOC_SETFLAGS _IOW('f', 2, long)
306#define EXT2_IOC_GETVERSION _IOR('v', 1, long)
307#define EXT2_IOC_SETVERSION _IOW('v', 2, long)
308#define EXT2_IOC_GETVERSION_NEW _IOR('f', 3, long)
309#define EXT2_IOC_SETVERSION_NEW _IOW('f', 4, long)
310#define EXT2_IOC_GROUP_EXTEND _IOW('f', 7, unsigned long)
311#define EXT2_IOC_GROUP_ADD _IOW('f', 8, struct ext2_new_group_input)
312#define EXT4_IOC_GROUP_ADD _IOW('f', 8, struct ext4_new_group_input)
313
314/*
315 * Structure of an inode on the disk
316 */
317struct ext2_inode {
318 __u16 i_mode; /* File mode */
319 __u16 i_uid; /* Low 16 bits of Owner Uid */
320 __u32 i_size; /* Size in bytes */
321 __u32 i_atime; /* Access time */
322 __u32 i_ctime; /* Inode change time */
323 __u32 i_mtime; /* Modification time */
324 __u32 i_dtime; /* Deletion Time */
325 __u16 i_gid; /* Low 16 bits of Group Id */
326 __u16 i_links_count; /* Links count */
327 __u32 i_blocks; /* Blocks count */
328 __u32 i_flags; /* File flags */
329 union {
330 struct {
331 __u32 l_i_version; /* was l_i_reserved1 */
332 } linux1;
333 struct {
334 __u32 h_i_translator;
335 } hurd1;
336 } osd1; /* OS dependent 1 */
337 __u32 i_block[EXT2_N_BLOCKS]; /* Pointers to blocks */
338 __u32 i_generation; /* File version (for NFS) */
339 __u32 i_file_acl; /* File ACL */
340 __u32 i_dir_acl; /* Directory ACL */
341 __u32 i_faddr; /* Fragment address */
342 union {
343 struct {
344 __u16 l_i_blocks_hi;
345 __u16 l_i_file_acl_high;
346 __u16 l_i_uid_high; /* these 2 fields */
347 __u16 l_i_gid_high; /* were reserved2[0] */
348 __u32 l_i_reserved2;
349 } linux2;
350 struct {
351 __u8 h_i_frag; /* Fragment number */
352 __u8 h_i_fsize; /* Fragment size */
353 __u16 h_i_mode_high;
354 __u16 h_i_uid_high;
355 __u16 h_i_gid_high;
356 __u32 h_i_author;
357 } hurd2;
358 } osd2; /* OS dependent 2 */
359};
360
361/*
362 * Permanent part of an large inode on the disk
363 */
364struct ext2_inode_large {
365 __u16 i_mode; /* File mode */
366 __u16 i_uid; /* Low 16 bits of Owner Uid */
367 __u32 i_size; /* Size in bytes */
368 __u32 i_atime; /* Access time */
369 __u32 i_ctime; /* Inode Change time */
370 __u32 i_mtime; /* Modification time */
371 __u32 i_dtime; /* Deletion Time */
372 __u16 i_gid; /* Low 16 bits of Group Id */
373 __u16 i_links_count; /* Links count */
374 __u32 i_blocks; /* Blocks count */
375 __u32 i_flags; /* File flags */
376 union {
377 struct {
378 __u32 l_i_version; /* was l_i_reserved1 */
379 } linux1;
380 struct {
381 __u32 h_i_translator;
382 } hurd1;
383 } osd1; /* OS dependent 1 */
384 __u32 i_block[EXT2_N_BLOCKS]; /* Pointers to blocks */
385 __u32 i_generation; /* File version (for NFS) */
386 __u32 i_file_acl; /* File ACL */
387 __u32 i_dir_acl; /* Directory ACL */
388 __u32 i_faddr; /* Fragment address */
389 union {
390 struct {
391 __u16 l_i_blocks_hi;
392 __u16 l_i_file_acl_high;
393 __u16 l_i_uid_high; /* these 2 fields */
394 __u16 l_i_gid_high; /* were reserved2[0] */
395 __u32 l_i_reserved2;
396 } linux2;
397 struct {
398 __u8 h_i_frag; /* Fragment number */
399 __u8 h_i_fsize; /* Fragment size */
400 __u16 h_i_mode_high;
401 __u16 h_i_uid_high;
402 __u16 h_i_gid_high;
403 __u32 h_i_author;
404 } hurd2;
405 } osd2; /* OS dependent 2 */
406 __u16 i_extra_isize;
407 __u16 i_pad1;
408 __u32 i_ctime_extra; /* extra Change time (nsec << 2 | epoch) */
409 __u32 i_mtime_extra; /* extra Modification time (nsec << 2 | epoch) */
410 __u32 i_atime_extra; /* extra Access time (nsec << 2 | epoch) */
411 __u32 i_crtime; /* File creation time */
412 __u32 i_crtime_extra; /* extra File creation time (nsec << 2 | epoch)*/
413 __u32 i_version_hi; /* high 32 bits for 64-bit version */
414};
415
416#define i_size_high i_dir_acl
417
418#if defined(__KERNEL__) || defined(__linux__)
419# define i_reserved1 osd1.linux1.l_i_reserved1
420# define i_frag osd2.linux2.l_i_frag
421# define i_fsize osd2.linux2.l_i_fsize
422# define i_uid_low i_uid
423# define i_gid_low i_gid
424# define i_uid_high osd2.linux2.l_i_uid_high
425# define i_gid_high osd2.linux2.l_i_gid_high
426# define i_reserved2 osd2.linux2.l_i_reserved2
427#else
428# if defined(__GNU__)
429
430# define i_translator osd1.hurd1.h_i_translator
431# define i_frag osd2.hurd2.h_i_frag;
432# define i_fsize osd2.hurd2.h_i_fsize;
433# define i_uid_high osd2.hurd2.h_i_uid_high
434# define i_gid_high osd2.hurd2.h_i_gid_high
435# define i_author osd2.hurd2.h_i_author
436
437# endif /* __GNU__ */
438#endif /* defined(__KERNEL__) || defined(__linux__) */
439
440#define inode_uid(inode) ((inode).i_uid | (inode).osd2.linux2.l_i_uid_high << 16)
441#define inode_gid(inode) ((inode).i_gid | (inode).osd2.linux2.l_i_gid_high << 16)
442#define ext2fs_set_i_uid_high(inode, x) ((inode).osd2.linux2.l_i_uid_high = (x))
443#define ext2fs_set_i_gid_high(inode, x) ((inode).osd2.linux2.l_i_gid_high = (x))
444
445/*
446 * File system states
447 */
448#define EXT2_VALID_FS 0x0001 /* Unmounted cleanly */
449#define EXT2_ERROR_FS 0x0002 /* Errors detected */
450#define EXT3_ORPHAN_FS 0x0004 /* Orphans being recovered */
451
452/*
453 * Misc. filesystem flags
454 */
455#define EXT2_FLAGS_SIGNED_HASH 0x0001 /* Signed dirhash in use */
456#define EXT2_FLAGS_UNSIGNED_HASH 0x0002 /* Unsigned dirhash in use */
457#define EXT2_FLAGS_TEST_FILESYS 0x0004 /* OK for use on development code */
458
459/*
460 * Mount flags
461 */
462#define EXT2_MOUNT_CHECK 0x0001 /* Do mount-time checks */
463#define EXT2_MOUNT_GRPID 0x0004 /* Create files with directory's group */
464#define EXT2_MOUNT_DEBUG 0x0008 /* Some debugging messages */
465#define EXT2_MOUNT_ERRORS_CONT 0x0010 /* Continue on errors */
466#define EXT2_MOUNT_ERRORS_RO 0x0020 /* Remount fs ro on errors */
467#define EXT2_MOUNT_ERRORS_PANIC 0x0040 /* Panic on errors */
468#define EXT2_MOUNT_MINIX_DF 0x0080 /* Mimics the Minix statfs */
469#define EXT2_MOUNT_NO_UID32 0x0200 /* Disable 32-bit UIDs */
470
471#define clear_opt(o, opt) o &= ~EXT2_MOUNT_##opt
472#define set_opt(o, opt) o |= EXT2_MOUNT_##opt
473#define test_opt(sb, opt) (EXT2_SB(sb)->s_mount_opt & EXT2_MOUNT_##opt)
474/*
475 * Maximal mount counts between two filesystem checks
476 */
477#define EXT2_DFL_MAX_MNT_COUNT 20 /* Allow 20 mounts */
478#define EXT2_DFL_CHECKINTERVAL 0 /* Don't use interval check */
479
480/*
481 * Behaviour when detecting errors
482 */
483#define EXT2_ERRORS_CONTINUE 1 /* Continue execution */
484#define EXT2_ERRORS_RO 2 /* Remount fs read-only */
485#define EXT2_ERRORS_PANIC 3 /* Panic */
486#define EXT2_ERRORS_DEFAULT EXT2_ERRORS_CONTINUE
487
488/*
489 * Structure of the super block
490 */
491struct ext2_super_block {
492 __u32 s_inodes_count; /* Inodes count */
493 __u32 s_blocks_count; /* Blocks count */
494 __u32 s_r_blocks_count; /* Reserved blocks count */
495 __u32 s_free_blocks_count; /* Free blocks count */
496 __u32 s_free_inodes_count; /* Free inodes count */
497 __u32 s_first_data_block; /* First Data Block */
498 __u32 s_log_block_size; /* Block size */
499 __s32 s_log_frag_size; /* Fragment size */
500 __u32 s_blocks_per_group; /* # Blocks per group */
501 __u32 s_frags_per_group; /* # Fragments per group */
502 __u32 s_inodes_per_group; /* # Inodes per group */
503 __u32 s_mtime; /* Mount time */
504 __u32 s_wtime; /* Write time */
505 __u16 s_mnt_count; /* Mount count */
506 __s16 s_max_mnt_count; /* Maximal mount count */
507 __u16 s_magic; /* Magic signature */
508 __u16 s_state; /* File system state */
509 __u16 s_errors; /* Behaviour when detecting errors */
510 __u16 s_minor_rev_level; /* minor revision level */
511 __u32 s_lastcheck; /* time of last check */
512 __u32 s_checkinterval; /* max. time between checks */
513 __u32 s_creator_os; /* OS */
514 __u32 s_rev_level; /* Revision level */
515 __u16 s_def_resuid; /* Default uid for reserved blocks */
516 __u16 s_def_resgid; /* Default gid for reserved blocks */
517 /*
518 * These fields are for EXT2_DYNAMIC_REV superblocks only.
519 *
520 * Note: the difference between the compatible feature set and
521 * the incompatible feature set is that if there is a bit set
522 * in the incompatible feature set that the kernel doesn't
523 * know about, it should refuse to mount the filesystem.
524 *
525 * e2fsck's requirements are more strict; if it doesn't know
526 * about a feature in either the compatible or incompatible
527 * feature set, it must abort and not try to meddle with
528 * things it doesn't understand...
529 */
530 __u32 s_first_ino; /* First non-reserved inode */
531 __u16 s_inode_size; /* size of inode structure */
532 __u16 s_block_group_nr; /* block group # of this superblock */
533 __u32 s_feature_compat; /* compatible feature set */
534 __u32 s_feature_incompat; /* incompatible feature set */
535 __u32 s_feature_ro_compat; /* readonly-compatible feature set */
536 __u8 s_uuid[16]; /* 128-bit uuid for volume */
537 char s_volume_name[16]; /* volume name */
538 char s_last_mounted[64]; /* directory where last mounted */
539 __u32 s_algorithm_usage_bitmap; /* For compression */
540 /*
541 * Performance hints. Directory preallocation should only
542 * happen if the EXT2_FEATURE_COMPAT_DIR_PREALLOC flag is on.
543 */
544 __u8 s_prealloc_blocks; /* Nr of blocks to try to preallocate*/
545 __u8 s_prealloc_dir_blocks; /* Nr to preallocate for dirs */
546 __u16 s_reserved_gdt_blocks; /* Per group table for online growth */
547 /*
548 * Journaling support valid if EXT2_FEATURE_COMPAT_HAS_JOURNAL set.
549 */
550 __u8 s_journal_uuid[16]; /* uuid of journal superblock */
551 __u32 s_journal_inum; /* inode number of journal file */
552 __u32 s_journal_dev; /* device number of journal file */
553 __u32 s_last_orphan; /* start of list of inodes to delete */
554 __u32 s_hash_seed[4]; /* HTREE hash seed */
555 __u8 s_def_hash_version; /* Default hash version to use */
556 __u8 s_jnl_backup_type; /* Default type of journal backup */
557 __u16 s_desc_size; /* Group desc. size: INCOMPAT_64BIT */
558 __u32 s_default_mount_opts;
559 __u32 s_first_meta_bg; /* First metablock group */
560 __u32 s_mkfs_time; /* When the filesystem was created */
561 __u32 s_jnl_blocks[17]; /* Backup of the journal inode */
562 __u32 s_blocks_count_hi; /* Blocks count high 32bits */
563 __u32 s_r_blocks_count_hi; /* Reserved blocks count high 32 bits*/
564 __u32 s_free_blocks_hi; /* Free blocks count */
565 __u16 s_min_extra_isize; /* All inodes have at least # bytes */
566 __u16 s_want_extra_isize; /* New inodes should reserve # bytes */
567 __u32 s_flags; /* Miscellaneous flags */
568 __u16 s_raid_stride; /* RAID stride */
569 __u16 s_mmp_interval; /* # seconds to wait in MMP checking */
570 __u64 s_mmp_block; /* Block for multi-mount protection */
571 __u32 s_raid_stripe_width; /* blocks on all data disks (N*stride)*/
572 __u8 s_log_groups_per_flex; /* FLEX_BG group size */
573 __u8 s_reserved_char_pad;
574 __u16 s_reserved_pad; /* Padding to next 32bits */
575 __u32 s_reserved[162]; /* Padding to the end of the block */
576};
577
578/*
579 * Codes for operating systems
580 */
581#define EXT2_OS_LINUX 0
582#define EXT2_OS_HURD 1
583#define EXT2_OBSO_OS_MASIX 2
584#define EXT2_OS_FREEBSD 3
585#define EXT2_OS_LITES 4
586
587/*
588 * Revision levels
589 */
590#define EXT2_GOOD_OLD_REV 0 /* The good old (original) format */
591#define EXT2_DYNAMIC_REV 1 /* V2 format w/ dynamic inode sizes */
592
593#define EXT2_CURRENT_REV EXT2_GOOD_OLD_REV
594#define EXT2_MAX_SUPP_REV EXT2_DYNAMIC_REV
595
596#define EXT2_GOOD_OLD_INODE_SIZE 128
597
598/*
599 * Journal inode backup types
600 */
601#define EXT3_JNL_BACKUP_BLOCKS 1
602
603/*
604 * Feature set definitions
605 */
606
607#define EXT2_HAS_COMPAT_FEATURE(sb, mask) \
608 (EXT2_SB(sb)->s_feature_compat & (mask))
609#define EXT2_HAS_RO_COMPAT_FEATURE(sb, mask) \
610 (EXT2_SB(sb)->s_feature_ro_compat & (mask))
611#define EXT2_HAS_INCOMPAT_FEATURE(sb, mask) \
612 (EXT2_SB(sb)->s_feature_incompat & (mask))
613
614#define EXT2_FEATURE_COMPAT_DIR_PREALLOC 0x0001
615#define EXT2_FEATURE_COMPAT_IMAGIC_INODES 0x0002
616#define EXT3_FEATURE_COMPAT_HAS_JOURNAL 0x0004
617#define EXT2_FEATURE_COMPAT_EXT_ATTR 0x0008
618#define EXT2_FEATURE_COMPAT_RESIZE_INODE 0x0010
619#define EXT2_FEATURE_COMPAT_DIR_INDEX 0x0020
620#define EXT2_FEATURE_COMPAT_LAZY_BG 0x0040
621
622#define EXT2_FEATURE_RO_COMPAT_SPARSE_SUPER 0x0001
623#define EXT2_FEATURE_RO_COMPAT_LARGE_FILE 0x0002
624/* #define EXT2_FEATURE_RO_COMPAT_BTREE_DIR 0x0004 not used */
625#define EXT4_FEATURE_RO_COMPAT_HUGE_FILE 0x0008
626#define EXT4_FEATURE_RO_COMPAT_GDT_CSUM 0x0010
627#define EXT4_FEATURE_RO_COMPAT_DIR_NLINK 0x0020
628#define EXT4_FEATURE_RO_COMPAT_EXTRA_ISIZE 0x0040
629
630#define EXT2_FEATURE_INCOMPAT_COMPRESSION 0x0001
631#define EXT2_FEATURE_INCOMPAT_FILETYPE 0x0002
632#define EXT3_FEATURE_INCOMPAT_RECOVER 0x0004 /* Needs recovery */
633#define EXT3_FEATURE_INCOMPAT_JOURNAL_DEV 0x0008 /* Journal device */
634#define EXT2_FEATURE_INCOMPAT_META_BG 0x0010
635#define EXT3_FEATURE_INCOMPAT_EXTENTS 0x0040
636#define EXT4_FEATURE_INCOMPAT_64BIT 0x0080
637#define EXT4_FEATURE_INCOMPAT_MMP 0x0100
638#define EXT4_FEATURE_INCOMPAT_FLEX_BG 0x0200
639
640#define EXT2_FEATURE_COMPAT_SUPP 0
641#define EXT2_FEATURE_INCOMPAT_SUPP (EXT2_FEATURE_INCOMPAT_FILETYPE)
642#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)
643
644/*
645 * Default values for user and/or group using reserved blocks
646 */
647#define EXT2_DEF_RESUID 0
648#define EXT2_DEF_RESGID 0
649
650/*
651 * Default mount options
652 */
653#define EXT2_DEFM_DEBUG 0x0001
654#define EXT2_DEFM_BSDGROUPS 0x0002
655#define EXT2_DEFM_XATTR_USER 0x0004
656#define EXT2_DEFM_ACL 0x0008
657#define EXT2_DEFM_UID16 0x0010
658#define EXT3_DEFM_JMODE 0x0060
659#define EXT3_DEFM_JMODE_DATA 0x0020
660#define EXT3_DEFM_JMODE_ORDERED 0x0040
661#define EXT3_DEFM_JMODE_WBACK 0x0060
662
663/*
664 * Structure of a directory entry
665 */
666#define EXT2_NAME_LEN 255
667
668struct ext2_dir_entry {
669 __u32 inode; /* Inode number */
670 __u16 rec_len; /* Directory entry length */
671 __u16 name_len; /* Name length */
672 char name[EXT2_NAME_LEN]; /* File name */
673};
674
675/*
676 * The new version of the directory entry. Since EXT2 structures are
677 * stored in intel byte order, and the name_len field could never be
678 * bigger than 255 chars, it's safe to reclaim the extra byte for the
679 * file_type field.
680 */
681struct ext2_dir_entry_2 {
682 __u32 inode; /* Inode number */
683 __u16 rec_len; /* Directory entry length */
684 __u8 name_len; /* Name length */
685 __u8 file_type;
686 char name[EXT2_NAME_LEN]; /* File name */
687};
688
689/*
690 * Ext2 directory file types. Only the low 3 bits are used. The
691 * other bits are reserved for now.
692 */
693#define EXT2_FT_UNKNOWN 0
694#define EXT2_FT_REG_FILE 1
695#define EXT2_FT_DIR 2
696#define EXT2_FT_CHRDEV 3
697#define EXT2_FT_BLKDEV 4
698#define EXT2_FT_FIFO 5
699#define EXT2_FT_SOCK 6
700#define EXT2_FT_SYMLINK 7
701
702#define EXT2_FT_MAX 8
703
704/*
705 * EXT2_DIR_PAD defines the directory entries boundaries
706 *
707 * NOTE: It must be a multiple of 4
708 */
709#define EXT2_DIR_PAD 4
710#define EXT2_DIR_ROUND (EXT2_DIR_PAD - 1)
711#define EXT2_DIR_REC_LEN(name_len) (((name_len) + 8 + EXT2_DIR_ROUND) & ~EXT2_DIR_ROUND)
712
713/*
714 * This structure will be used for multiple mount protection. It will be
715 * written into the block number saved in the s_mmp_block field in the
716 * superblock.
717 */
718#define EXT2_MMP_MAGIC 0x004D4D50 /* ASCII for MMP */
719#define EXT2_MMP_CLEAN 0xFF4D4D50 /* Value of mmp_seq for clean unmount */
720#define EXT2_MMP_FSCK_ON 0xE24D4D50 /* Value of mmp_seq when being fscked */
721
722struct mmp_struct {
723 __u32 mmp_magic;
724 __u32 mmp_seq;
725 __u64 mmp_time;
726 char mmp_nodename[64];
727 char mmp_bdevname[32];
728 __u16 mmp_interval;
729 __u16 mmp_pad1;
730 __u32 mmp_pad2;
731};
732
733/*
734 * Interval in number of seconds to update the MMP sequence number.
735 */
736#define EXT2_MMP_DEF_INTERVAL 5
737
738#endif /* _LINUX_EXT2_FS_H */