blob: fab43527e597402da88de4d6777216e685076e0d [file] [log] [blame]
Linus Torvalds1da177e2005-04-16 15:20:36 -07001/*
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 <linux/types.h>
20#include <linux/ext2_fs_sb.h>
21
22/*
23 * The second extended filesystem constants/structures
24 */
25
26/*
27 * Define EXT2FS_DEBUG to produce debug messages
28 */
29#undef EXT2FS_DEBUG
30
31/*
32 * Define EXT2_PREALLOCATE to preallocate data blocks for expanding files
33 */
34#define EXT2_PREALLOCATE
35#define EXT2_DEFAULT_PREALLOC_BLOCKS 8
36
37/*
38 * The second extended file system version
39 */
40#define EXT2FS_DATE "95/08/09"
41#define EXT2FS_VERSION "0.5b"
42
43/*
44 * Debug code
45 */
46#ifdef EXT2FS_DEBUG
47# define ext2_debug(f, a...) { \
48 printk ("EXT2-fs DEBUG (%s, %d): %s:", \
49 __FILE__, __LINE__, __FUNCTION__); \
50 printk (f, ## a); \
51 }
52#else
53# define ext2_debug(f, a...) /**/
54#endif
55
56/*
57 * Special inode numbers
58 */
59#define EXT2_BAD_INO 1 /* Bad blocks inode */
60#define EXT2_ROOT_INO 2 /* Root inode */
61#define EXT2_BOOT_LOADER_INO 5 /* Boot loader inode */
62#define EXT2_UNDEL_DIR_INO 6 /* Undelete directory inode */
63
64/* First non-reserved inode for old ext2 filesystems */
65#define EXT2_GOOD_OLD_FIRST_INO 11
66
67/*
68 * The second extended file system magic number
69 */
70#define EXT2_SUPER_MAGIC 0xEF53
71
72#ifdef __KERNEL__
73static inline struct ext2_sb_info *EXT2_SB(struct super_block *sb)
74{
75 return sb->s_fs_info;
76}
77#else
78/* Assume that user mode programs are passing in an ext2fs superblock, not
79 * a kernel struct super_block. This will allow us to call the feature-test
80 * macros from user land. */
81#define EXT2_SB(sb) (sb)
82#endif
83
84/*
85 * Maximal count of links to a file
86 */
87#define EXT2_LINK_MAX 32000
88
89/*
90 * Macro-instructions used to manage several block sizes
91 */
92#define EXT2_MIN_BLOCK_SIZE 1024
93#define EXT2_MAX_BLOCK_SIZE 4096
94#define EXT2_MIN_BLOCK_LOG_SIZE 10
95#ifdef __KERNEL__
96# define EXT2_BLOCK_SIZE(s) ((s)->s_blocksize)
97#else
98# define EXT2_BLOCK_SIZE(s) (EXT2_MIN_BLOCK_SIZE << (s)->s_log_block_size)
99#endif
100#define EXT2_ADDR_PER_BLOCK(s) (EXT2_BLOCK_SIZE(s) / sizeof (__u32))
101#ifdef __KERNEL__
102# define EXT2_BLOCK_SIZE_BITS(s) ((s)->s_blocksize_bits)
103#else
104# define EXT2_BLOCK_SIZE_BITS(s) ((s)->s_log_block_size + 10)
105#endif
106#ifdef __KERNEL__
107#define EXT2_ADDR_PER_BLOCK_BITS(s) (EXT2_SB(s)->s_addr_per_block_bits)
108#define EXT2_INODE_SIZE(s) (EXT2_SB(s)->s_inode_size)
109#define EXT2_FIRST_INO(s) (EXT2_SB(s)->s_first_ino)
110#else
111#define EXT2_INODE_SIZE(s) (((s)->s_rev_level == EXT2_GOOD_OLD_REV) ? \
112 EXT2_GOOD_OLD_INODE_SIZE : \
113 (s)->s_inode_size)
114#define EXT2_FIRST_INO(s) (((s)->s_rev_level == EXT2_GOOD_OLD_REV) ? \
115 EXT2_GOOD_OLD_FIRST_INO : \
116 (s)->s_first_ino)
117#endif
118
119/*
120 * Macro-instructions used to manage fragments
121 */
122#define EXT2_MIN_FRAG_SIZE 1024
123#define EXT2_MAX_FRAG_SIZE 4096
124#define EXT2_MIN_FRAG_LOG_SIZE 10
125#ifdef __KERNEL__
126# define EXT2_FRAG_SIZE(s) (EXT2_SB(s)->s_frag_size)
127# define EXT2_FRAGS_PER_BLOCK(s) (EXT2_SB(s)->s_frags_per_block)
128#else
129# define EXT2_FRAG_SIZE(s) (EXT2_MIN_FRAG_SIZE << (s)->s_log_frag_size)
130# define EXT2_FRAGS_PER_BLOCK(s) (EXT2_BLOCK_SIZE(s) / EXT2_FRAG_SIZE(s))
131#endif
132
133/*
134 * Structure of a blocks group descriptor
135 */
136struct ext2_group_desc
137{
138 __le32 bg_block_bitmap; /* Blocks bitmap block */
139 __le32 bg_inode_bitmap; /* Inodes bitmap block */
140 __le32 bg_inode_table; /* Inodes table block */
141 __le16 bg_free_blocks_count; /* Free blocks count */
142 __le16 bg_free_inodes_count; /* Free inodes count */
143 __le16 bg_used_dirs_count; /* Directories count */
144 __le16 bg_pad;
145 __le32 bg_reserved[3];
146};
147
148/*
149 * Macro-instructions used to manage group descriptors
150 */
151#ifdef __KERNEL__
152# define EXT2_BLOCKS_PER_GROUP(s) (EXT2_SB(s)->s_blocks_per_group)
153# define EXT2_DESC_PER_BLOCK(s) (EXT2_SB(s)->s_desc_per_block)
154# define EXT2_INODES_PER_GROUP(s) (EXT2_SB(s)->s_inodes_per_group)
155# define EXT2_DESC_PER_BLOCK_BITS(s) (EXT2_SB(s)->s_desc_per_block_bits)
156#else
157# define EXT2_BLOCKS_PER_GROUP(s) ((s)->s_blocks_per_group)
158# define EXT2_DESC_PER_BLOCK(s) (EXT2_BLOCK_SIZE(s) / sizeof (struct ext2_group_desc))
159# define EXT2_INODES_PER_GROUP(s) ((s)->s_inodes_per_group)
160#endif
161
162/*
163 * Constants relative to the data blocks
164 */
165#define EXT2_NDIR_BLOCKS 12
166#define EXT2_IND_BLOCK EXT2_NDIR_BLOCKS
167#define EXT2_DIND_BLOCK (EXT2_IND_BLOCK + 1)
168#define EXT2_TIND_BLOCK (EXT2_DIND_BLOCK + 1)
169#define EXT2_N_BLOCKS (EXT2_TIND_BLOCK + 1)
170
171/*
172 * Inode flags
173 */
174#define EXT2_SECRM_FL 0x00000001 /* Secure deletion */
175#define EXT2_UNRM_FL 0x00000002 /* Undelete */
176#define EXT2_COMPR_FL 0x00000004 /* Compress file */
177#define EXT2_SYNC_FL 0x00000008 /* Synchronous updates */
178#define EXT2_IMMUTABLE_FL 0x00000010 /* Immutable file */
179#define EXT2_APPEND_FL 0x00000020 /* writes to file may only append */
180#define EXT2_NODUMP_FL 0x00000040 /* do not dump file */
181#define EXT2_NOATIME_FL 0x00000080 /* do not update atime */
182/* Reserved for compression usage... */
183#define EXT2_DIRTY_FL 0x00000100
184#define EXT2_COMPRBLK_FL 0x00000200 /* One or more compressed clusters */
185#define EXT2_NOCOMP_FL 0x00000400 /* Don't compress */
186#define EXT2_ECOMPR_FL 0x00000800 /* Compression error */
187/* End compression flags --- maybe not all used */
188#define EXT2_BTREE_FL 0x00001000 /* btree format dir */
189#define EXT2_INDEX_FL 0x00001000 /* hash-indexed directory */
190#define EXT2_IMAGIC_FL 0x00002000 /* AFS directory */
191#define EXT2_JOURNAL_DATA_FL 0x00004000 /* Reserved for ext3 */
192#define EXT2_NOTAIL_FL 0x00008000 /* file tail should not be merged */
193#define EXT2_DIRSYNC_FL 0x00010000 /* dirsync behaviour (directories only) */
194#define EXT2_TOPDIR_FL 0x00020000 /* Top of directory hierarchies*/
195#define EXT2_RESERVED_FL 0x80000000 /* reserved for ext2 lib */
196
197#define EXT2_FL_USER_VISIBLE 0x0003DFFF /* User visible flags */
198#define EXT2_FL_USER_MODIFIABLE 0x000380FF /* User modifiable flags */
199
200/*
201 * ioctl commands
202 */
203#define EXT2_IOC_GETFLAGS _IOR('f', 1, long)
204#define EXT2_IOC_SETFLAGS _IOW('f', 2, long)
205#define EXT2_IOC_GETVERSION _IOR('v', 1, long)
206#define EXT2_IOC_SETVERSION _IOW('v', 2, long)
207
208/*
209 * Structure of an inode on the disk
210 */
211struct ext2_inode {
212 __le16 i_mode; /* File mode */
213 __le16 i_uid; /* Low 16 bits of Owner Uid */
214 __le32 i_size; /* Size in bytes */
215 __le32 i_atime; /* Access time */
216 __le32 i_ctime; /* Creation time */
217 __le32 i_mtime; /* Modification time */
218 __le32 i_dtime; /* Deletion Time */
219 __le16 i_gid; /* Low 16 bits of Group Id */
220 __le16 i_links_count; /* Links count */
221 __le32 i_blocks; /* Blocks count */
222 __le32 i_flags; /* File flags */
223 union {
224 struct {
225 __le32 l_i_reserved1;
226 } linux1;
227 struct {
228 __le32 h_i_translator;
229 } hurd1;
230 struct {
231 __le32 m_i_reserved1;
232 } masix1;
233 } osd1; /* OS dependent 1 */
234 __le32 i_block[EXT2_N_BLOCKS];/* Pointers to blocks */
235 __le32 i_generation; /* File version (for NFS) */
236 __le32 i_file_acl; /* File ACL */
237 __le32 i_dir_acl; /* Directory ACL */
238 __le32 i_faddr; /* Fragment address */
239 union {
240 struct {
241 __u8 l_i_frag; /* Fragment number */
242 __u8 l_i_fsize; /* Fragment size */
243 __u16 i_pad1;
244 __le16 l_i_uid_high; /* these 2 fields */
245 __le16 l_i_gid_high; /* were reserved2[0] */
246 __u32 l_i_reserved2;
247 } linux2;
248 struct {
249 __u8 h_i_frag; /* Fragment number */
250 __u8 h_i_fsize; /* Fragment size */
251 __le16 h_i_mode_high;
252 __le16 h_i_uid_high;
253 __le16 h_i_gid_high;
254 __le32 h_i_author;
255 } hurd2;
256 struct {
257 __u8 m_i_frag; /* Fragment number */
258 __u8 m_i_fsize; /* Fragment size */
259 __u16 m_pad1;
260 __u32 m_i_reserved2[2];
261 } masix2;
262 } osd2; /* OS dependent 2 */
263};
264
265#define i_size_high i_dir_acl
266
267#if defined(__KERNEL__) || defined(__linux__)
268#define i_reserved1 osd1.linux1.l_i_reserved1
269#define i_frag osd2.linux2.l_i_frag
270#define i_fsize osd2.linux2.l_i_fsize
271#define i_uid_low i_uid
272#define i_gid_low i_gid
273#define i_uid_high osd2.linux2.l_i_uid_high
274#define i_gid_high osd2.linux2.l_i_gid_high
275#define i_reserved2 osd2.linux2.l_i_reserved2
276#endif
277
278#ifdef __hurd__
279#define i_translator osd1.hurd1.h_i_translator
280#define i_frag osd2.hurd2.h_i_frag;
281#define i_fsize osd2.hurd2.h_i_fsize;
282#define i_uid_high osd2.hurd2.h_i_uid_high
283#define i_gid_high osd2.hurd2.h_i_gid_high
284#define i_author osd2.hurd2.h_i_author
285#endif
286
287#ifdef __masix__
288#define i_reserved1 osd1.masix1.m_i_reserved1
289#define i_frag osd2.masix2.m_i_frag
290#define i_fsize osd2.masix2.m_i_fsize
291#define i_reserved2 osd2.masix2.m_i_reserved2
292#endif
293
294/*
295 * File system states
296 */
297#define EXT2_VALID_FS 0x0001 /* Unmounted cleanly */
298#define EXT2_ERROR_FS 0x0002 /* Errors detected */
299
300/*
301 * Mount flags
302 */
303#define EXT2_MOUNT_CHECK 0x0001 /* Do mount-time checks */
304#define EXT2_MOUNT_OLDALLOC 0x0002 /* Don't use the new Orlov allocator */
305#define EXT2_MOUNT_GRPID 0x0004 /* Create files with directory's group */
306#define EXT2_MOUNT_DEBUG 0x0008 /* Some debugging messages */
307#define EXT2_MOUNT_ERRORS_CONT 0x0010 /* Continue on errors */
308#define EXT2_MOUNT_ERRORS_RO 0x0020 /* Remount fs ro on errors */
309#define EXT2_MOUNT_ERRORS_PANIC 0x0040 /* Panic on errors */
310#define EXT2_MOUNT_MINIX_DF 0x0080 /* Mimics the Minix statfs */
311#define EXT2_MOUNT_NOBH 0x0100 /* No buffer_heads */
312#define EXT2_MOUNT_NO_UID32 0x0200 /* Disable 32-bit UIDs */
313#define EXT2_MOUNT_XATTR_USER 0x4000 /* Extended user attributes */
314#define EXT2_MOUNT_POSIX_ACL 0x8000 /* POSIX Access Control Lists */
315
316#define clear_opt(o, opt) o &= ~EXT2_MOUNT_##opt
317#define set_opt(o, opt) o |= EXT2_MOUNT_##opt
318#define test_opt(sb, opt) (EXT2_SB(sb)->s_mount_opt & \
319 EXT2_MOUNT_##opt)
320/*
321 * Maximal mount counts between two filesystem checks
322 */
323#define EXT2_DFL_MAX_MNT_COUNT 20 /* Allow 20 mounts */
324#define EXT2_DFL_CHECKINTERVAL 0 /* Don't use interval check */
325
326/*
327 * Behaviour when detecting errors
328 */
329#define EXT2_ERRORS_CONTINUE 1 /* Continue execution */
330#define EXT2_ERRORS_RO 2 /* Remount fs read-only */
331#define EXT2_ERRORS_PANIC 3 /* Panic */
332#define EXT2_ERRORS_DEFAULT EXT2_ERRORS_CONTINUE
333
334/*
335 * Structure of the super block
336 */
337struct ext2_super_block {
338 __le32 s_inodes_count; /* Inodes count */
339 __le32 s_blocks_count; /* Blocks count */
340 __le32 s_r_blocks_count; /* Reserved blocks count */
341 __le32 s_free_blocks_count; /* Free blocks count */
342 __le32 s_free_inodes_count; /* Free inodes count */
343 __le32 s_first_data_block; /* First Data Block */
344 __le32 s_log_block_size; /* Block size */
345 __le32 s_log_frag_size; /* Fragment size */
346 __le32 s_blocks_per_group; /* # Blocks per group */
347 __le32 s_frags_per_group; /* # Fragments per group */
348 __le32 s_inodes_per_group; /* # Inodes per group */
349 __le32 s_mtime; /* Mount time */
350 __le32 s_wtime; /* Write time */
351 __le16 s_mnt_count; /* Mount count */
352 __le16 s_max_mnt_count; /* Maximal mount count */
353 __le16 s_magic; /* Magic signature */
354 __le16 s_state; /* File system state */
355 __le16 s_errors; /* Behaviour when detecting errors */
356 __le16 s_minor_rev_level; /* minor revision level */
357 __le32 s_lastcheck; /* time of last check */
358 __le32 s_checkinterval; /* max. time between checks */
359 __le32 s_creator_os; /* OS */
360 __le32 s_rev_level; /* Revision level */
361 __le16 s_def_resuid; /* Default uid for reserved blocks */
362 __le16 s_def_resgid; /* Default gid for reserved blocks */
363 /*
364 * These fields are for EXT2_DYNAMIC_REV superblocks only.
365 *
366 * Note: the difference between the compatible feature set and
367 * the incompatible feature set is that if there is a bit set
368 * in the incompatible feature set that the kernel doesn't
369 * know about, it should refuse to mount the filesystem.
370 *
371 * e2fsck's requirements are more strict; if it doesn't know
372 * about a feature in either the compatible or incompatible
373 * feature set, it must abort and not try to meddle with
374 * things it doesn't understand...
375 */
376 __le32 s_first_ino; /* First non-reserved inode */
377 __le16 s_inode_size; /* size of inode structure */
378 __le16 s_block_group_nr; /* block group # of this superblock */
379 __le32 s_feature_compat; /* compatible feature set */
380 __le32 s_feature_incompat; /* incompatible feature set */
381 __le32 s_feature_ro_compat; /* readonly-compatible feature set */
382 __u8 s_uuid[16]; /* 128-bit uuid for volume */
383 char s_volume_name[16]; /* volume name */
384 char s_last_mounted[64]; /* directory where last mounted */
385 __le32 s_algorithm_usage_bitmap; /* For compression */
386 /*
387 * Performance hints. Directory preallocation should only
388 * happen if the EXT2_COMPAT_PREALLOC flag is on.
389 */
390 __u8 s_prealloc_blocks; /* Nr of blocks to try to preallocate*/
391 __u8 s_prealloc_dir_blocks; /* Nr to preallocate for dirs */
392 __u16 s_padding1;
393 /*
394 * Journaling support valid if EXT3_FEATURE_COMPAT_HAS_JOURNAL set.
395 */
396 __u8 s_journal_uuid[16]; /* uuid of journal superblock */
397 __u32 s_journal_inum; /* inode number of journal file */
398 __u32 s_journal_dev; /* device number of journal file */
399 __u32 s_last_orphan; /* start of list of inodes to delete */
400 __u32 s_hash_seed[4]; /* HTREE hash seed */
401 __u8 s_def_hash_version; /* Default hash version to use */
402 __u8 s_reserved_char_pad;
403 __u16 s_reserved_word_pad;
404 __le32 s_default_mount_opts;
405 __le32 s_first_meta_bg; /* First metablock block group */
406 __u32 s_reserved[190]; /* Padding to the end of the block */
407};
408
409/*
410 * Codes for operating systems
411 */
412#define EXT2_OS_LINUX 0
413#define EXT2_OS_HURD 1
414#define EXT2_OS_MASIX 2
415#define EXT2_OS_FREEBSD 3
416#define EXT2_OS_LITES 4
417
418/*
419 * Revision levels
420 */
421#define EXT2_GOOD_OLD_REV 0 /* The good old (original) format */
422#define EXT2_DYNAMIC_REV 1 /* V2 format w/ dynamic inode sizes */
423
424#define EXT2_CURRENT_REV EXT2_GOOD_OLD_REV
425#define EXT2_MAX_SUPP_REV EXT2_DYNAMIC_REV
426
427#define EXT2_GOOD_OLD_INODE_SIZE 128
428
429/*
430 * Feature set definitions
431 */
432
433#define EXT2_HAS_COMPAT_FEATURE(sb,mask) \
434 ( EXT2_SB(sb)->s_es->s_feature_compat & cpu_to_le32(mask) )
435#define EXT2_HAS_RO_COMPAT_FEATURE(sb,mask) \
436 ( EXT2_SB(sb)->s_es->s_feature_ro_compat & cpu_to_le32(mask) )
437#define EXT2_HAS_INCOMPAT_FEATURE(sb,mask) \
438 ( EXT2_SB(sb)->s_es->s_feature_incompat & cpu_to_le32(mask) )
439#define EXT2_SET_COMPAT_FEATURE(sb,mask) \
440 EXT2_SB(sb)->s_es->s_feature_compat |= cpu_to_le32(mask)
441#define EXT2_SET_RO_COMPAT_FEATURE(sb,mask) \
442 EXT2_SB(sb)->s_es->s_feature_ro_compat |= cpu_to_le32(mask)
443#define EXT2_SET_INCOMPAT_FEATURE(sb,mask) \
444 EXT2_SB(sb)->s_es->s_feature_incompat |= cpu_to_le32(mask)
445#define EXT2_CLEAR_COMPAT_FEATURE(sb,mask) \
446 EXT2_SB(sb)->s_es->s_feature_compat &= ~cpu_to_le32(mask)
447#define EXT2_CLEAR_RO_COMPAT_FEATURE(sb,mask) \
448 EXT2_SB(sb)->s_es->s_feature_ro_compat &= ~cpu_to_le32(mask)
449#define EXT2_CLEAR_INCOMPAT_FEATURE(sb,mask) \
450 EXT2_SB(sb)->s_es->s_feature_incompat &= ~cpu_to_le32(mask)
451
452#define EXT2_FEATURE_COMPAT_DIR_PREALLOC 0x0001
453#define EXT2_FEATURE_COMPAT_IMAGIC_INODES 0x0002
454#define EXT3_FEATURE_COMPAT_HAS_JOURNAL 0x0004
455#define EXT2_FEATURE_COMPAT_EXT_ATTR 0x0008
456#define EXT2_FEATURE_COMPAT_RESIZE_INO 0x0010
457#define EXT2_FEATURE_COMPAT_DIR_INDEX 0x0020
458#define EXT2_FEATURE_COMPAT_ANY 0xffffffff
459
460#define EXT2_FEATURE_RO_COMPAT_SPARSE_SUPER 0x0001
461#define EXT2_FEATURE_RO_COMPAT_LARGE_FILE 0x0002
462#define EXT2_FEATURE_RO_COMPAT_BTREE_DIR 0x0004
463#define EXT2_FEATURE_RO_COMPAT_ANY 0xffffffff
464
465#define EXT2_FEATURE_INCOMPAT_COMPRESSION 0x0001
466#define EXT2_FEATURE_INCOMPAT_FILETYPE 0x0002
467#define EXT3_FEATURE_INCOMPAT_RECOVER 0x0004
468#define EXT3_FEATURE_INCOMPAT_JOURNAL_DEV 0x0008
469#define EXT2_FEATURE_INCOMPAT_META_BG 0x0010
470#define EXT2_FEATURE_INCOMPAT_ANY 0xffffffff
471
472#define EXT2_FEATURE_COMPAT_SUPP EXT2_FEATURE_COMPAT_EXT_ATTR
473#define EXT2_FEATURE_INCOMPAT_SUPP (EXT2_FEATURE_INCOMPAT_FILETYPE| \
474 EXT2_FEATURE_INCOMPAT_META_BG)
475#define EXT2_FEATURE_RO_COMPAT_SUPP (EXT2_FEATURE_RO_COMPAT_SPARSE_SUPER| \
476 EXT2_FEATURE_RO_COMPAT_LARGE_FILE| \
477 EXT2_FEATURE_RO_COMPAT_BTREE_DIR)
478#define EXT2_FEATURE_RO_COMPAT_UNSUPPORTED ~EXT2_FEATURE_RO_COMPAT_SUPP
479#define EXT2_FEATURE_INCOMPAT_UNSUPPORTED ~EXT2_FEATURE_INCOMPAT_SUPP
480
481/*
482 * Default values for user and/or group using reserved blocks
483 */
484#define EXT2_DEF_RESUID 0
485#define EXT2_DEF_RESGID 0
486
487/*
488 * Default mount options
489 */
490#define EXT2_DEFM_DEBUG 0x0001
491#define EXT2_DEFM_BSDGROUPS 0x0002
492#define EXT2_DEFM_XATTR_USER 0x0004
493#define EXT2_DEFM_ACL 0x0008
494#define EXT2_DEFM_UID16 0x0010
495 /* Not used by ext2, but reserved for use by ext3 */
496#define EXT3_DEFM_JMODE 0x0060
497#define EXT3_DEFM_JMODE_DATA 0x0020
498#define EXT3_DEFM_JMODE_ORDERED 0x0040
499#define EXT3_DEFM_JMODE_WBACK 0x0060
500
501/*
502 * Structure of a directory entry
503 */
504#define EXT2_NAME_LEN 255
505
506struct ext2_dir_entry {
507 __le32 inode; /* Inode number */
508 __le16 rec_len; /* Directory entry length */
509 __le16 name_len; /* Name length */
510 char name[EXT2_NAME_LEN]; /* File name */
511};
512
513/*
514 * The new version of the directory entry. Since EXT2 structures are
515 * stored in intel byte order, and the name_len field could never be
516 * bigger than 255 chars, it's safe to reclaim the extra byte for the
517 * file_type field.
518 */
519struct ext2_dir_entry_2 {
520 __le32 inode; /* Inode number */
521 __le16 rec_len; /* Directory entry length */
522 __u8 name_len; /* Name length */
523 __u8 file_type;
524 char name[EXT2_NAME_LEN]; /* File name */
525};
526
527/*
528 * Ext2 directory file types. Only the low 3 bits are used. The
529 * other bits are reserved for now.
530 */
531enum {
532 EXT2_FT_UNKNOWN,
533 EXT2_FT_REG_FILE,
534 EXT2_FT_DIR,
535 EXT2_FT_CHRDEV,
536 EXT2_FT_BLKDEV,
537 EXT2_FT_FIFO,
538 EXT2_FT_SOCK,
539 EXT2_FT_SYMLINK,
540 EXT2_FT_MAX
541};
542
543/*
544 * EXT2_DIR_PAD defines the directory entries boundaries
545 *
546 * NOTE: It must be a multiple of 4
547 */
548#define EXT2_DIR_PAD 4
549#define EXT2_DIR_ROUND (EXT2_DIR_PAD - 1)
550#define EXT2_DIR_REC_LEN(name_len) (((name_len) + 8 + EXT2_DIR_ROUND) & \
551 ~EXT2_DIR_ROUND)
552
553#endif /* _LINUX_EXT2_FS_H */