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 <linux/types.h>
20 #include <linux/magic.h>
23 * The second extended filesystem constants/structures
27 * Define EXT2FS_DEBUG to produce debug messages
32 * Define EXT2_RESERVATION to reserve data blocks for expanding files
34 #define EXT2_DEFAULT_RESERVE_BLOCKS 8
35 /*max window size: 1024(direct blocks) + 3([t,d]indirect blocks) */
36 #define EXT2_MAX_RESERVE_BLOCKS 1027
37 #define EXT2_RESERVE_WINDOW_NOT_ALLOCATED 0
39 * The second extended file system version
41 #define EXT2FS_DATE "95/08/09"
42 #define EXT2FS_VERSION "0.5b"
48 # define ext2_debug(f, a...) { \
49 printk ("EXT2-fs DEBUG (%s, %d): %s:", \
50 __FILE__, __LINE__, __FUNCTION__); \
54 # define ext2_debug(f, a...) /**/
58 * Special inode numbers
60 #define EXT2_BAD_INO 1 /* Bad blocks inode */
61 #define EXT2_ROOT_INO 2 /* Root inode */
62 #define EXT2_BOOT_LOADER_INO 5 /* Boot loader inode */
63 #define EXT2_UNDEL_DIR_INO 6 /* Undelete directory inode */
65 /* First non-reserved inode for old ext2 filesystems */
66 #define EXT2_GOOD_OLD_FIRST_INO 11
69 #include <linux/ext2_fs_sb.h>
70 static inline struct ext2_sb_info
*EXT2_SB(struct super_block
*sb
)
75 /* Assume that user mode programs are passing in an ext2fs superblock, not
76 * a kernel struct super_block. This will allow us to call the feature-test
77 * macros from user land. */
78 #define EXT2_SB(sb) (sb)
82 * Maximal count of links to a file
84 #define EXT2_LINK_MAX 32000
87 * Macro-instructions used to manage several block sizes
89 #define EXT2_MIN_BLOCK_SIZE 1024
90 #define EXT2_MAX_BLOCK_SIZE 4096
91 #define EXT2_MIN_BLOCK_LOG_SIZE 10
93 # define EXT2_BLOCK_SIZE(s) ((s)->s_blocksize)
95 # define EXT2_BLOCK_SIZE(s) (EXT2_MIN_BLOCK_SIZE << (s)->s_log_block_size)
97 #define EXT2_ADDR_PER_BLOCK(s) (EXT2_BLOCK_SIZE(s) / sizeof (__u32))
99 # define EXT2_BLOCK_SIZE_BITS(s) ((s)->s_blocksize_bits)
101 # define EXT2_BLOCK_SIZE_BITS(s) ((s)->s_log_block_size + 10)
104 #define EXT2_ADDR_PER_BLOCK_BITS(s) (EXT2_SB(s)->s_addr_per_block_bits)
105 #define EXT2_INODE_SIZE(s) (EXT2_SB(s)->s_inode_size)
106 #define EXT2_FIRST_INO(s) (EXT2_SB(s)->s_first_ino)
108 #define EXT2_INODE_SIZE(s) (((s)->s_rev_level == EXT2_GOOD_OLD_REV) ? \
109 EXT2_GOOD_OLD_INODE_SIZE : \
111 #define EXT2_FIRST_INO(s) (((s)->s_rev_level == EXT2_GOOD_OLD_REV) ? \
112 EXT2_GOOD_OLD_FIRST_INO : \
117 * Macro-instructions used to manage fragments
119 #define EXT2_MIN_FRAG_SIZE 1024
120 #define EXT2_MAX_FRAG_SIZE 4096
121 #define EXT2_MIN_FRAG_LOG_SIZE 10
123 # define EXT2_FRAG_SIZE(s) (EXT2_SB(s)->s_frag_size)
124 # define EXT2_FRAGS_PER_BLOCK(s) (EXT2_SB(s)->s_frags_per_block)
126 # define EXT2_FRAG_SIZE(s) (EXT2_MIN_FRAG_SIZE << (s)->s_log_frag_size)
127 # define EXT2_FRAGS_PER_BLOCK(s) (EXT2_BLOCK_SIZE(s) / EXT2_FRAG_SIZE(s))
131 * Structure of a blocks group descriptor
133 struct ext2_group_desc
135 __le32 bg_block_bitmap
; /* Blocks bitmap block */
136 __le32 bg_inode_bitmap
; /* Inodes bitmap block */
137 __le32 bg_inode_table
; /* Inodes table block */
138 __le16 bg_free_blocks_count
; /* Free blocks count */
139 __le16 bg_free_inodes_count
; /* Free inodes count */
140 __le16 bg_used_dirs_count
; /* Directories count */
142 __le32 bg_reserved
[3];
146 * Macro-instructions used to manage group descriptors
149 # define EXT2_BLOCKS_PER_GROUP(s) (EXT2_SB(s)->s_blocks_per_group)
150 # define EXT2_DESC_PER_BLOCK(s) (EXT2_SB(s)->s_desc_per_block)
151 # define EXT2_INODES_PER_GROUP(s) (EXT2_SB(s)->s_inodes_per_group)
152 # define EXT2_DESC_PER_BLOCK_BITS(s) (EXT2_SB(s)->s_desc_per_block_bits)
154 # define EXT2_BLOCKS_PER_GROUP(s) ((s)->s_blocks_per_group)
155 # define EXT2_DESC_PER_BLOCK(s) (EXT2_BLOCK_SIZE(s) / sizeof (struct ext2_group_desc))
156 # define EXT2_INODES_PER_GROUP(s) ((s)->s_inodes_per_group)
160 * Constants relative to the data blocks
162 #define EXT2_NDIR_BLOCKS 12
163 #define EXT2_IND_BLOCK EXT2_NDIR_BLOCKS
164 #define EXT2_DIND_BLOCK (EXT2_IND_BLOCK + 1)
165 #define EXT2_TIND_BLOCK (EXT2_DIND_BLOCK + 1)
166 #define EXT2_N_BLOCKS (EXT2_TIND_BLOCK + 1)
169 * Inode flags (GETFLAGS/SETFLAGS)
171 #define EXT2_SECRM_FL FS_SECRM_FL /* Secure deletion */
172 #define EXT2_UNRM_FL FS_UNRM_FL /* Undelete */
173 #define EXT2_COMPR_FL FS_COMPR_FL /* Compress file */
174 #define EXT2_SYNC_FL FS_SYNC_FL /* Synchronous updates */
175 #define EXT2_IMMUTABLE_FL FS_IMMUTABLE_FL /* Immutable file */
176 #define EXT2_APPEND_FL FS_APPEND_FL /* writes to file may only append */
177 #define EXT2_NODUMP_FL FS_NODUMP_FL /* do not dump file */
178 #define EXT2_NOATIME_FL FS_NOATIME_FL /* do not update atime */
179 /* Reserved for compression usage... */
180 #define EXT2_DIRTY_FL FS_DIRTY_FL
181 #define EXT2_COMPRBLK_FL FS_COMPRBLK_FL /* One or more compressed clusters */
182 #define EXT2_NOCOMP_FL FS_NOCOMP_FL /* Don't compress */
183 #define EXT2_ECOMPR_FL FS_ECOMPR_FL /* Compression error */
184 /* End compression flags --- maybe not all used */
185 #define EXT2_BTREE_FL FS_BTREE_FL /* btree format dir */
186 #define EXT2_INDEX_FL FS_INDEX_FL /* hash-indexed directory */
187 #define EXT2_IMAGIC_FL FS_IMAGIC_FL /* AFS directory */
188 #define EXT2_JOURNAL_DATA_FL FS_JOURNAL_DATA_FL /* Reserved for ext3 */
189 #define EXT2_NOTAIL_FL FS_NOTAIL_FL /* file tail should not be merged */
190 #define EXT2_DIRSYNC_FL FS_DIRSYNC_FL /* dirsync behaviour (directories only) */
191 #define EXT2_TOPDIR_FL FS_TOPDIR_FL /* Top of directory hierarchies*/
192 #define EXT2_RESERVED_FL FS_RESERVED_FL /* reserved for ext2 lib */
194 #define EXT2_FL_USER_VISIBLE FS_FL_USER_VISIBLE /* User visible flags */
195 #define EXT2_FL_USER_MODIFIABLE FS_FL_USER_MODIFIABLE /* User modifiable flags */
200 #define EXT2_IOC_GETFLAGS FS_IOC_GETFLAGS
201 #define EXT2_IOC_SETFLAGS FS_IOC_SETFLAGS
202 #define EXT2_IOC_GETVERSION FS_IOC_GETVERSION
203 #define EXT2_IOC_SETVERSION FS_IOC_SETVERSION
204 #define EXT2_IOC_GETRSVSZ _IOR('f', 5, long)
205 #define EXT2_IOC_SETRSVSZ _IOW('f', 6, long)
208 * ioctl commands in 32 bit emulation
210 #define EXT2_IOC32_GETFLAGS FS_IOC32_GETFLAGS
211 #define EXT2_IOC32_SETFLAGS FS_IOC32_SETFLAGS
212 #define EXT2_IOC32_GETVERSION FS_IOC32_GETVERSION
213 #define EXT2_IOC32_SETVERSION FS_IOC32_SETVERSION
216 * Structure of an inode on the disk
219 __le16 i_mode
; /* File mode */
220 __le16 i_uid
; /* Low 16 bits of Owner Uid */
221 __le32 i_size
; /* Size in bytes */
222 __le32 i_atime
; /* Access time */
223 __le32 i_ctime
; /* Creation time */
224 __le32 i_mtime
; /* Modification time */
225 __le32 i_dtime
; /* Deletion Time */
226 __le16 i_gid
; /* Low 16 bits of Group Id */
227 __le16 i_links_count
; /* Links count */
228 __le32 i_blocks
; /* Blocks count */
229 __le32 i_flags
; /* File flags */
232 __le32 l_i_reserved1
;
235 __le32 h_i_translator
;
238 __le32 m_i_reserved1
;
240 } osd1
; /* OS dependent 1 */
241 __le32 i_block
[EXT2_N_BLOCKS
];/* Pointers to blocks */
242 __le32 i_generation
; /* File version (for NFS) */
243 __le32 i_file_acl
; /* File ACL */
244 __le32 i_dir_acl
; /* Directory ACL */
245 __le32 i_faddr
; /* Fragment address */
248 __u8 l_i_frag
; /* Fragment number */
249 __u8 l_i_fsize
; /* Fragment size */
251 __le16 l_i_uid_high
; /* these 2 fields */
252 __le16 l_i_gid_high
; /* were reserved2[0] */
256 __u8 h_i_frag
; /* Fragment number */
257 __u8 h_i_fsize
; /* Fragment size */
258 __le16 h_i_mode_high
;
264 __u8 m_i_frag
; /* Fragment number */
265 __u8 m_i_fsize
; /* Fragment size */
267 __u32 m_i_reserved2
[2];
269 } osd2
; /* OS dependent 2 */
272 #define i_size_high i_dir_acl
274 #if defined(__KERNEL__) || defined(__linux__)
275 #define i_reserved1 osd1.linux1.l_i_reserved1
276 #define i_frag osd2.linux2.l_i_frag
277 #define i_fsize osd2.linux2.l_i_fsize
278 #define i_uid_low i_uid
279 #define i_gid_low i_gid
280 #define i_uid_high osd2.linux2.l_i_uid_high
281 #define i_gid_high osd2.linux2.l_i_gid_high
282 #define i_reserved2 osd2.linux2.l_i_reserved2
286 #define i_translator osd1.hurd1.h_i_translator
287 #define i_frag osd2.hurd2.h_i_frag
288 #define i_fsize osd2.hurd2.h_i_fsize
289 #define i_uid_high osd2.hurd2.h_i_uid_high
290 #define i_gid_high osd2.hurd2.h_i_gid_high
291 #define i_author osd2.hurd2.h_i_author
295 #define i_reserved1 osd1.masix1.m_i_reserved1
296 #define i_frag osd2.masix2.m_i_frag
297 #define i_fsize osd2.masix2.m_i_fsize
298 #define i_reserved2 osd2.masix2.m_i_reserved2
304 #define EXT2_VALID_FS 0x0001 /* Unmounted cleanly */
305 #define EXT2_ERROR_FS 0x0002 /* Errors detected */
310 #define EXT2_MOUNT_CHECK 0x000001 /* Do mount-time checks */
311 #define EXT2_MOUNT_OLDALLOC 0x000002 /* Don't use the new Orlov allocator */
312 #define EXT2_MOUNT_GRPID 0x000004 /* Create files with directory's group */
313 #define EXT2_MOUNT_DEBUG 0x000008 /* Some debugging messages */
314 #define EXT2_MOUNT_ERRORS_CONT 0x000010 /* Continue on errors */
315 #define EXT2_MOUNT_ERRORS_RO 0x000020 /* Remount fs ro on errors */
316 #define EXT2_MOUNT_ERRORS_PANIC 0x000040 /* Panic on errors */
317 #define EXT2_MOUNT_MINIX_DF 0x000080 /* Mimics the Minix statfs */
318 #define EXT2_MOUNT_NOBH 0x000100 /* No buffer_heads */
319 #define EXT2_MOUNT_NO_UID32 0x000200 /* Disable 32-bit UIDs */
320 #define EXT2_MOUNT_XATTR_USER 0x004000 /* Extended user attributes */
321 #define EXT2_MOUNT_POSIX_ACL 0x008000 /* POSIX Access Control Lists */
322 #define EXT2_MOUNT_XIP 0x010000 /* Execute in place */
323 #define EXT2_MOUNT_USRQUOTA 0x020000 /* user quota */
324 #define EXT2_MOUNT_GRPQUOTA 0x040000 /* group quota */
325 #define EXT2_MOUNT_RESERVATION 0x080000 /* Preallocation */
328 #define clear_opt(o, opt) o &= ~EXT2_MOUNT_##opt
329 #define set_opt(o, opt) o |= EXT2_MOUNT_##opt
330 #define test_opt(sb, opt) (EXT2_SB(sb)->s_mount_opt & \
333 * Maximal mount counts between two filesystem checks
335 #define EXT2_DFL_MAX_MNT_COUNT 20 /* Allow 20 mounts */
336 #define EXT2_DFL_CHECKINTERVAL 0 /* Don't use interval check */
339 * Behaviour when detecting errors
341 #define EXT2_ERRORS_CONTINUE 1 /* Continue execution */
342 #define EXT2_ERRORS_RO 2 /* Remount fs read-only */
343 #define EXT2_ERRORS_PANIC 3 /* Panic */
344 #define EXT2_ERRORS_DEFAULT EXT2_ERRORS_CONTINUE
347 * Structure of the super block
349 struct ext2_super_block
{
350 __le32 s_inodes_count
; /* Inodes count */
351 __le32 s_blocks_count
; /* Blocks count */
352 __le32 s_r_blocks_count
; /* Reserved blocks count */
353 __le32 s_free_blocks_count
; /* Free blocks count */
354 __le32 s_free_inodes_count
; /* Free inodes count */
355 __le32 s_first_data_block
; /* First Data Block */
356 __le32 s_log_block_size
; /* Block size */
357 __le32 s_log_frag_size
; /* Fragment size */
358 __le32 s_blocks_per_group
; /* # Blocks per group */
359 __le32 s_frags_per_group
; /* # Fragments per group */
360 __le32 s_inodes_per_group
; /* # Inodes per group */
361 __le32 s_mtime
; /* Mount time */
362 __le32 s_wtime
; /* Write time */
363 __le16 s_mnt_count
; /* Mount count */
364 __le16 s_max_mnt_count
; /* Maximal mount count */
365 __le16 s_magic
; /* Magic signature */
366 __le16 s_state
; /* File system state */
367 __le16 s_errors
; /* Behaviour when detecting errors */
368 __le16 s_minor_rev_level
; /* minor revision level */
369 __le32 s_lastcheck
; /* time of last check */
370 __le32 s_checkinterval
; /* max. time between checks */
371 __le32 s_creator_os
; /* OS */
372 __le32 s_rev_level
; /* Revision level */
373 __le16 s_def_resuid
; /* Default uid for reserved blocks */
374 __le16 s_def_resgid
; /* Default gid for reserved blocks */
376 * These fields are for EXT2_DYNAMIC_REV superblocks only.
378 * Note: the difference between the compatible feature set and
379 * the incompatible feature set is that if there is a bit set
380 * in the incompatible feature set that the kernel doesn't
381 * know about, it should refuse to mount the filesystem.
383 * e2fsck's requirements are more strict; if it doesn't know
384 * about a feature in either the compatible or incompatible
385 * feature set, it must abort and not try to meddle with
386 * things it doesn't understand...
388 __le32 s_first_ino
; /* First non-reserved inode */
389 __le16 s_inode_size
; /* size of inode structure */
390 __le16 s_block_group_nr
; /* block group # of this superblock */
391 __le32 s_feature_compat
; /* compatible feature set */
392 __le32 s_feature_incompat
; /* incompatible feature set */
393 __le32 s_feature_ro_compat
; /* readonly-compatible feature set */
394 __u8 s_uuid
[16]; /* 128-bit uuid for volume */
395 char s_volume_name
[16]; /* volume name */
396 char s_last_mounted
[64]; /* directory where last mounted */
397 __le32 s_algorithm_usage_bitmap
; /* For compression */
399 * Performance hints. Directory preallocation should only
400 * happen if the EXT2_COMPAT_PREALLOC flag is on.
402 __u8 s_prealloc_blocks
; /* Nr of blocks to try to preallocate*/
403 __u8 s_prealloc_dir_blocks
; /* Nr to preallocate for dirs */
406 * Journaling support valid if EXT3_FEATURE_COMPAT_HAS_JOURNAL set.
408 __u8 s_journal_uuid
[16]; /* uuid of journal superblock */
409 __u32 s_journal_inum
; /* inode number of journal file */
410 __u32 s_journal_dev
; /* device number of journal file */
411 __u32 s_last_orphan
; /* start of list of inodes to delete */
412 __u32 s_hash_seed
[4]; /* HTREE hash seed */
413 __u8 s_def_hash_version
; /* Default hash version to use */
414 __u8 s_reserved_char_pad
;
415 __u16 s_reserved_word_pad
;
416 __le32 s_default_mount_opts
;
417 __le32 s_first_meta_bg
; /* First metablock block group */
418 __u32 s_reserved
[190]; /* Padding to the end of the block */
422 * Codes for operating systems
424 #define EXT2_OS_LINUX 0
425 #define EXT2_OS_HURD 1
426 #define EXT2_OS_MASIX 2
427 #define EXT2_OS_FREEBSD 3
428 #define EXT2_OS_LITES 4
433 #define EXT2_GOOD_OLD_REV 0 /* The good old (original) format */
434 #define EXT2_DYNAMIC_REV 1 /* V2 format w/ dynamic inode sizes */
436 #define EXT2_CURRENT_REV EXT2_GOOD_OLD_REV
437 #define EXT2_MAX_SUPP_REV EXT2_DYNAMIC_REV
439 #define EXT2_GOOD_OLD_INODE_SIZE 128
442 * Feature set definitions
445 #define EXT2_HAS_COMPAT_FEATURE(sb,mask) \
446 ( EXT2_SB(sb)->s_es->s_feature_compat & cpu_to_le32(mask) )
447 #define EXT2_HAS_RO_COMPAT_FEATURE(sb,mask) \
448 ( EXT2_SB(sb)->s_es->s_feature_ro_compat & cpu_to_le32(mask) )
449 #define EXT2_HAS_INCOMPAT_FEATURE(sb,mask) \
450 ( EXT2_SB(sb)->s_es->s_feature_incompat & cpu_to_le32(mask) )
451 #define EXT2_SET_COMPAT_FEATURE(sb,mask) \
452 EXT2_SB(sb)->s_es->s_feature_compat |= cpu_to_le32(mask)
453 #define EXT2_SET_RO_COMPAT_FEATURE(sb,mask) \
454 EXT2_SB(sb)->s_es->s_feature_ro_compat |= cpu_to_le32(mask)
455 #define EXT2_SET_INCOMPAT_FEATURE(sb,mask) \
456 EXT2_SB(sb)->s_es->s_feature_incompat |= cpu_to_le32(mask)
457 #define EXT2_CLEAR_COMPAT_FEATURE(sb,mask) \
458 EXT2_SB(sb)->s_es->s_feature_compat &= ~cpu_to_le32(mask)
459 #define EXT2_CLEAR_RO_COMPAT_FEATURE(sb,mask) \
460 EXT2_SB(sb)->s_es->s_feature_ro_compat &= ~cpu_to_le32(mask)
461 #define EXT2_CLEAR_INCOMPAT_FEATURE(sb,mask) \
462 EXT2_SB(sb)->s_es->s_feature_incompat &= ~cpu_to_le32(mask)
464 #define EXT2_FEATURE_COMPAT_DIR_PREALLOC 0x0001
465 #define EXT2_FEATURE_COMPAT_IMAGIC_INODES 0x0002
466 #define EXT3_FEATURE_COMPAT_HAS_JOURNAL 0x0004
467 #define EXT2_FEATURE_COMPAT_EXT_ATTR 0x0008
468 #define EXT2_FEATURE_COMPAT_RESIZE_INO 0x0010
469 #define EXT2_FEATURE_COMPAT_DIR_INDEX 0x0020
470 #define EXT2_FEATURE_COMPAT_ANY 0xffffffff
472 #define EXT2_FEATURE_RO_COMPAT_SPARSE_SUPER 0x0001
473 #define EXT2_FEATURE_RO_COMPAT_LARGE_FILE 0x0002
474 #define EXT2_FEATURE_RO_COMPAT_BTREE_DIR 0x0004
475 #define EXT2_FEATURE_RO_COMPAT_ANY 0xffffffff
477 #define EXT2_FEATURE_INCOMPAT_COMPRESSION 0x0001
478 #define EXT2_FEATURE_INCOMPAT_FILETYPE 0x0002
479 #define EXT3_FEATURE_INCOMPAT_RECOVER 0x0004
480 #define EXT3_FEATURE_INCOMPAT_JOURNAL_DEV 0x0008
481 #define EXT2_FEATURE_INCOMPAT_META_BG 0x0010
482 #define EXT2_FEATURE_INCOMPAT_ANY 0xffffffff
484 #define EXT2_FEATURE_COMPAT_SUPP EXT2_FEATURE_COMPAT_EXT_ATTR
485 #define EXT2_FEATURE_INCOMPAT_SUPP (EXT2_FEATURE_INCOMPAT_FILETYPE| \
486 EXT2_FEATURE_INCOMPAT_META_BG)
487 #define EXT2_FEATURE_RO_COMPAT_SUPP (EXT2_FEATURE_RO_COMPAT_SPARSE_SUPER| \
488 EXT2_FEATURE_RO_COMPAT_LARGE_FILE| \
489 EXT2_FEATURE_RO_COMPAT_BTREE_DIR)
490 #define EXT2_FEATURE_RO_COMPAT_UNSUPPORTED ~EXT2_FEATURE_RO_COMPAT_SUPP
491 #define EXT2_FEATURE_INCOMPAT_UNSUPPORTED ~EXT2_FEATURE_INCOMPAT_SUPP
494 * Default values for user and/or group using reserved blocks
496 #define EXT2_DEF_RESUID 0
497 #define EXT2_DEF_RESGID 0
500 * Default mount options
502 #define EXT2_DEFM_DEBUG 0x0001
503 #define EXT2_DEFM_BSDGROUPS 0x0002
504 #define EXT2_DEFM_XATTR_USER 0x0004
505 #define EXT2_DEFM_ACL 0x0008
506 #define EXT2_DEFM_UID16 0x0010
507 /* Not used by ext2, but reserved for use by ext3 */
508 #define EXT3_DEFM_JMODE 0x0060
509 #define EXT3_DEFM_JMODE_DATA 0x0020
510 #define EXT3_DEFM_JMODE_ORDERED 0x0040
511 #define EXT3_DEFM_JMODE_WBACK 0x0060
514 * Structure of a directory entry
516 #define EXT2_NAME_LEN 255
518 struct ext2_dir_entry
{
519 __le32 inode
; /* Inode number */
520 __le16 rec_len
; /* Directory entry length */
521 __le16 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 __le32 inode
; /* Inode number */
533 __le16 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.
556 * EXT2_DIR_PAD defines the directory entries boundaries
558 * NOTE: It must be a multiple of 4
560 #define EXT2_DIR_PAD 4
561 #define EXT2_DIR_ROUND (EXT2_DIR_PAD - 1)
562 #define EXT2_DIR_REC_LEN(name_len) (((name_len) + 8 + EXT2_DIR_ROUND) & \
564 #define EXT2_MAX_REC_LEN ((1<<16)-1)
566 #endif /* _LINUX_EXT2_FS_H */