2efe7b863cff361301d4a73c1c4e46338d0b02b1
[linux-2.6.git] / include / linux / ext2_fs.h
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 <linux/types.h>
20 #include <linux/magic.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_RESERVATION to reserve data blocks for expanding files
33  */
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
38 /*
39  * The second extended file system version
40  */
41 #define EXT2FS_DATE             "95/08/09"
42 #define EXT2FS_VERSION          "0.5b"
43
44 /*
45  * Debug code
46  */
47 #ifdef EXT2FS_DEBUG
48 #       define ext2_debug(f, a...)      { \
49                                         printk ("EXT2-fs DEBUG (%s, %d): %s:", \
50                                                 __FILE__, __LINE__, __FUNCTION__); \
51                                         printk (f, ## a); \
52                                         }
53 #else
54 #       define ext2_debug(f, a...)      /**/
55 #endif
56
57 /*
58  * Special inode numbers
59  */
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 */
64
65 /* First non-reserved inode for old ext2 filesystems */
66 #define EXT2_GOOD_OLD_FIRST_INO 11
67
68 #ifdef __KERNEL__
69 #include <linux/ext2_fs_sb.h>
70 static inline struct ext2_sb_info *EXT2_SB(struct super_block *sb)
71 {
72         return sb->s_fs_info;
73 }
74 #else
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)
79 #endif
80
81 /*
82  * Maximal count of links to a file
83  */
84 #define EXT2_LINK_MAX           32000
85
86 /*
87  * Macro-instructions used to manage several block sizes
88  */
89 #define EXT2_MIN_BLOCK_SIZE             1024
90 #define EXT2_MAX_BLOCK_SIZE             4096
91 #define EXT2_MIN_BLOCK_LOG_SIZE           10
92 #ifdef __KERNEL__
93 # define EXT2_BLOCK_SIZE(s)             ((s)->s_blocksize)
94 #else
95 # define EXT2_BLOCK_SIZE(s)             (EXT2_MIN_BLOCK_SIZE << (s)->s_log_block_size)
96 #endif
97 #define EXT2_ADDR_PER_BLOCK(s)          (EXT2_BLOCK_SIZE(s) / sizeof (__u32))
98 #ifdef __KERNEL__
99 # define EXT2_BLOCK_SIZE_BITS(s)        ((s)->s_blocksize_bits)
100 #else
101 # define EXT2_BLOCK_SIZE_BITS(s)        ((s)->s_log_block_size + 10)
102 #endif
103 #ifdef __KERNEL__
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)
107 #else
108 #define EXT2_INODE_SIZE(s)      (((s)->s_rev_level == EXT2_GOOD_OLD_REV) ? \
109                                  EXT2_GOOD_OLD_INODE_SIZE : \
110                                  (s)->s_inode_size)
111 #define EXT2_FIRST_INO(s)       (((s)->s_rev_level == EXT2_GOOD_OLD_REV) ? \
112                                  EXT2_GOOD_OLD_FIRST_INO : \
113                                  (s)->s_first_ino)
114 #endif
115
116 /*
117  * Macro-instructions used to manage fragments
118  */
119 #define EXT2_MIN_FRAG_SIZE              1024
120 #define EXT2_MAX_FRAG_SIZE              4096
121 #define EXT2_MIN_FRAG_LOG_SIZE            10
122 #ifdef __KERNEL__
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)
125 #else
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))
128 #endif
129
130 /*
131  * Structure of a blocks group descriptor
132  */
133 struct ext2_group_desc
134 {
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 */
141         __le16  bg_pad;
142         __le32  bg_reserved[3];
143 };
144
145 /*
146  * Macro-instructions used to manage group descriptors
147  */
148 #ifdef __KERNEL__
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)
153 #else
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)
157 #endif
158
159 /*
160  * Constants relative to the data blocks
161  */
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)
167
168 /*
169  * Inode flags (GETFLAGS/SETFLAGS)
170  */
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 */
193
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 */
196
197 /*
198  * ioctl commands
199  */
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)
206
207 /*
208  * ioctl commands in 32 bit emulation
209  */
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
214
215 /*
216  * Structure of an inode on the disk
217  */
218 struct ext2_inode {
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 */
230         union {
231                 struct {
232                         __le32  l_i_reserved1;
233                 } linux1;
234                 struct {
235                         __le32  h_i_translator;
236                 } hurd1;
237                 struct {
238                         __le32  m_i_reserved1;
239                 } masix1;
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 */
246         union {
247                 struct {
248                         __u8    l_i_frag;       /* Fragment number */
249                         __u8    l_i_fsize;      /* Fragment size */
250                         __u16   i_pad1;
251                         __le16  l_i_uid_high;   /* these 2 fields    */
252                         __le16  l_i_gid_high;   /* were reserved2[0] */
253                         __u32   l_i_reserved2;
254                 } linux2;
255                 struct {
256                         __u8    h_i_frag;       /* Fragment number */
257                         __u8    h_i_fsize;      /* Fragment size */
258                         __le16  h_i_mode_high;
259                         __le16  h_i_uid_high;
260                         __le16  h_i_gid_high;
261                         __le32  h_i_author;
262                 } hurd2;
263                 struct {
264                         __u8    m_i_frag;       /* Fragment number */
265                         __u8    m_i_fsize;      /* Fragment size */
266                         __u16   m_pad1;
267                         __u32   m_i_reserved2[2];
268                 } masix2;
269         } osd2;                         /* OS dependent 2 */
270 };
271
272 #define i_size_high     i_dir_acl
273
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
283 #endif
284
285 #ifdef  __hurd__
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
292 #endif
293
294 #ifdef  __masix__
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
299 #endif
300
301 /*
302  * File system states
303  */
304 #define EXT2_VALID_FS                   0x0001  /* Unmounted cleanly */
305 #define EXT2_ERROR_FS                   0x0002  /* Errors detected */
306
307 /*
308  * Mount flags
309  */
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 */
326
327
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 & \
331                                          EXT2_MOUNT_##opt)
332 /*
333  * Maximal mount counts between two filesystem checks
334  */
335 #define EXT2_DFL_MAX_MNT_COUNT          20      /* Allow 20 mounts */
336 #define EXT2_DFL_CHECKINTERVAL          0       /* Don't use interval check */
337
338 /*
339  * Behaviour when detecting errors
340  */
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
345
346 /*
347  * Structure of the super block
348  */
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 */
375         /*
376          * These fields are for EXT2_DYNAMIC_REV superblocks only.
377          *
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.
382          * 
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...
387          */
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 */
398         /*
399          * Performance hints.  Directory preallocation should only
400          * happen if the EXT2_COMPAT_PREALLOC flag is on.
401          */
402         __u8    s_prealloc_blocks;      /* Nr of blocks to try to preallocate*/
403         __u8    s_prealloc_dir_blocks;  /* Nr to preallocate for dirs */
404         __u16   s_padding1;
405         /*
406          * Journaling support valid if EXT3_FEATURE_COMPAT_HAS_JOURNAL set.
407          */
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 */
419 };
420
421 /*
422  * Codes for operating systems
423  */
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
429
430 /*
431  * Revision levels
432  */
433 #define EXT2_GOOD_OLD_REV       0       /* The good old (original) format */
434 #define EXT2_DYNAMIC_REV        1       /* V2 format w/ dynamic inode sizes */
435
436 #define EXT2_CURRENT_REV        EXT2_GOOD_OLD_REV
437 #define EXT2_MAX_SUPP_REV       EXT2_DYNAMIC_REV
438
439 #define EXT2_GOOD_OLD_INODE_SIZE 128
440
441 /*
442  * Feature set definitions
443  */
444
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)
463
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
471
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
476
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
483
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
492
493 /*
494  * Default values for user and/or group using reserved blocks
495  */
496 #define EXT2_DEF_RESUID         0
497 #define EXT2_DEF_RESGID         0
498
499 /*
500  * Default mount options
501  */
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
512
513 /*
514  * Structure of a directory entry
515  */
516 #define EXT2_NAME_LEN 255
517
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 */
523 };
524
525 /*
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
529  * file_type field.
530  */
531 struct ext2_dir_entry_2 {
532         __le32  inode;                  /* Inode number */
533         __le16  rec_len;                /* Directory entry length */
534         __u8    name_len;               /* Name length */
535         __u8    file_type;
536         char    name[EXT2_NAME_LEN];    /* File name */
537 };
538
539 /*
540  * Ext2 directory file types.  Only the low 3 bits are used.  The
541  * other bits are reserved for now.
542  */
543 enum {
544         EXT2_FT_UNKNOWN,
545         EXT2_FT_REG_FILE,
546         EXT2_FT_DIR,
547         EXT2_FT_CHRDEV,
548         EXT2_FT_BLKDEV,
549         EXT2_FT_FIFO,
550         EXT2_FT_SOCK,
551         EXT2_FT_SYMLINK,
552         EXT2_FT_MAX
553 };
554
555 /*
556  * EXT2_DIR_PAD defines the directory entries boundaries
557  *
558  * NOTE: It must be a multiple of 4
559  */
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) & \
563                                          ~EXT2_DIR_ROUND)
564 #define EXT2_MAX_REC_LEN                ((1<<16)-1)
565
566 #endif  /* _LINUX_EXT2_FS_H */