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>
22 * The second extended filesystem constants/structures
26 * Define EXT2FS_DEBUG to produce debug messages
31 * Define EXT2_PREALLOCATE to preallocate data blocks for expanding files
33 #define EXT2_PREALLOCATE
36 * The second extended file system version
38 #define EXT2FS_DATE "95/08/09"
39 #define EXT2FS_VERSION "0.5b"
46 # define ext2_debug(f, a...) { \
47 printk ("EXT2-fs DEBUG (%s, %d): %s:", \
48 __FILE__, __LINE__, __FUNCTION__); \
52 # define ext2_debug(f, a...) /**/
57 * Special inodes numbers
59 #define EXT2_BAD_INO 1 /* Bad blocks inode */
60 #define EXT2_ROOT_INO 2 /* Root inode */
61 #define EXT2_ACL_IDX_INO 3 /* ACL inode */
62 #define EXT2_ACL_DATA_INO 4 /* ACL inode */
63 #define EXT2_BOOT_LOADER_INO 5 /* Boot loader inode */
64 #define EXT2_UNDEL_DIR_INO 6 /* Undelete directory inode */
66 /* First non-reserved inode for old ext2 filesystems */
67 #define EXT2_GOOD_OLD_FIRST_INO 11
70 * The second extended file system magic number
72 #define EXT2_SUPER_MAGIC 0xEF53
75 * Maximal count of links to a file
77 #define EXT2_LINK_MAX 32000
80 * Macro-instructions used to manage several block sizes
82 #define EXT2_MIN_BLOCK_SIZE 1024
83 #define EXT2_MAX_BLOCK_SIZE 4096
84 #define EXT2_MIN_BLOCK_LOG_SIZE 10
86 # define EXT2_BLOCK_SIZE(s) ((s)->s_blocksize)
88 # define EXT2_BLOCK_SIZE(s) (EXT2_MIN_BLOCK_SIZE << (s)->s_log_block_size)
90 #define EXT2_ACLE_PER_BLOCK(s) (EXT2_BLOCK_SIZE(s) / sizeof (struct ext2_acl_entry))
91 #define EXT2_ADDR_PER_BLOCK(s) (EXT2_BLOCK_SIZE(s) / sizeof (__u32))
93 # define EXT2_BLOCK_SIZE_BITS(s) ((s)->s_blocksize_bits)
95 # define EXT2_BLOCK_SIZE_BITS(s) ((s)->s_log_block_size + 10)
98 #define EXT2_ADDR_PER_BLOCK_BITS(s) ((s)->u.ext2_sb.s_addr_per_block_bits)
99 #define EXT2_INODE_SIZE(s) ((s)->u.ext2_sb.s_inode_size)
100 #define EXT2_FIRST_INO(s) ((s)->u.ext2_sb.s_first_ino)
102 #define EXT2_INODE_SIZE(s) (((s)->s_rev_level == EXT2_GOOD_OLD_REV) ? \
103 EXT2_GOOD_OLD_INODE_SIZE : \
105 #define EXT2_FIRST_INO(s) (((s)->s_rev_level == EXT2_GOOD_OLD_REV) ? \
106 EXT2_GOOD_OLD_FIRST_INO : \
111 * Macro-instructions used to manage fragments
113 #define EXT2_MIN_FRAG_SIZE 1024
114 #define EXT2_MAX_FRAG_SIZE 4096
115 #define EXT2_MIN_FRAG_LOG_SIZE 10
117 # define EXT2_FRAG_SIZE(s) ((s)->u.ext2_sb.s_frag_size)
118 # define EXT2_FRAGS_PER_BLOCK(s) ((s)->u.ext2_sb.s_frags_per_block)
120 # define EXT2_FRAG_SIZE(s) (EXT2_MIN_FRAG_SIZE << (s)->s_log_frag_size)
121 # define EXT2_FRAGS_PER_BLOCK(s) (EXT2_BLOCK_SIZE(s) / EXT2_FRAG_SIZE(s))
127 struct ext2_acl_header /* Header of Access Control Lists */
130 __u32 aclh_file_count;
131 __u32 aclh_acle_count;
132 __u32 aclh_first_acle;
135 struct ext2_acl_entry /* Access Control List Entry */
138 __u16 acle_perms; /* Access permissions */
139 __u16 acle_type; /* Type of entry */
140 __u16 acle_tag; /* User or group identity */
142 __u32 acle_next; /* Pointer on next entry for the */
143 /* same inode or on next free entry */
147 * Structure of a blocks group descriptor
149 struct ext2_group_desc
151 __u32 bg_block_bitmap; /* Blocks bitmap block */
152 __u32 bg_inode_bitmap; /* Inodes bitmap block */
153 __u32 bg_inode_table; /* Inodes table block */
154 __u16 bg_free_blocks_count; /* Free blocks count */
155 __u16 bg_free_inodes_count; /* Free inodes count */
156 __u16 bg_used_dirs_count; /* Directories count */
158 __u32 bg_reserved[3];
162 * Macro-instructions used to manage group descriptors
165 # define EXT2_BLOCKS_PER_GROUP(s) ((s)->u.ext2_sb.s_blocks_per_group)
166 # define EXT2_DESC_PER_BLOCK(s) ((s)->u.ext2_sb.s_desc_per_block)
167 # define EXT2_INODES_PER_GROUP(s) ((s)->u.ext2_sb.s_inodes_per_group)
168 # define EXT2_DESC_PER_BLOCK_BITS(s) ((s)->u.ext2_sb.s_desc_per_block_bits)
170 # define EXT2_BLOCKS_PER_GROUP(s) ((s)->s_blocks_per_group)
171 # define EXT2_DESC_PER_BLOCK(s) (EXT2_BLOCK_SIZE(s) / sizeof (struct ext2_group_desc))
172 # define EXT2_INODES_PER_GROUP(s) ((s)->s_inodes_per_group)
176 * Constants relative to the data blocks
178 #define EXT2_NDIR_BLOCKS 12
179 #define EXT2_IND_BLOCK EXT2_NDIR_BLOCKS
180 #define EXT2_DIND_BLOCK (EXT2_IND_BLOCK + 1)
181 #define EXT2_TIND_BLOCK (EXT2_DIND_BLOCK + 1)
182 #define EXT2_N_BLOCKS (EXT2_TIND_BLOCK + 1)
187 #define EXT2_SECRM_FL 0x00000001 /* Secure deletion */
188 #define EXT2_UNRM_FL 0x00000002 /* Undelete */
189 #define EXT2_COMPR_FL 0x00000004 /* Compress file */
190 #define EXT2_SYNC_FL 0x00000008 /* Synchronous updates */
191 #define EXT2_IMMUTABLE_FL 0x00000010 /* Immutable file */
192 #define EXT2_APPEND_FL 0x00000020 /* writes to file may only append */
193 #define EXT2_NODUMP_FL 0x00000040 /* do not dump file */
194 #define EXT2_NOATIME_FL 0x00000080 /* do not update atime */
195 #define EXT2_RESERVED_FL 0x80000000 /* reserved for ext2 lib */
200 #define EXT2_IOC_GETFLAGS _IOR('f', 1, long)
201 #define EXT2_IOC_SETFLAGS _IOW('f', 2, long)
202 #define EXT2_IOC_GETVERSION _IOR('v', 1, long)
203 #define EXT2_IOC_SETVERSION _IOW('v', 2, long)
206 * Structure of an inode on the disk
209 __u16 i_mode; /* File mode */
210 __u16 i_uid; /* Owner Uid */
211 __u32 i_size; /* Size in bytes */
212 __u32 i_atime; /* Access time */
213 __u32 i_ctime; /* Creation time */
214 __u32 i_mtime; /* Modification time */
215 __u32 i_dtime; /* Deletion Time */
216 __u16 i_gid; /* Group Id */
217 __u16 i_links_count; /* Links count */
218 __u32 i_blocks; /* Blocks count */
219 __u32 i_flags; /* File flags */
225 __u32 h_i_translator;
230 } osd1; /* OS dependent 1 */
231 __u32 i_block[EXT2_N_BLOCKS];/* Pointers to blocks */
232 __u32 i_version; /* File version (for NFS) */
233 __u32 i_file_acl; /* File ACL */
234 __u32 i_dir_acl; /* Directory ACL */
235 __u32 i_faddr; /* Fragment address */
238 __u8 l_i_frag; /* Fragment number */
239 __u8 l_i_fsize; /* Fragment size */
241 __u32 l_i_reserved2[2];
244 __u8 h_i_frag; /* Fragment number */
245 __u8 h_i_fsize; /* Fragment size */
252 __u8 m_i_frag; /* Fragment number */
253 __u8 m_i_fsize; /* Fragment size */
255 __u32 m_i_reserved2[2];
257 } osd2; /* OS dependent 2 */
260 #if defined(__KERNEL__) || defined(__linux__)
261 #define i_reserved1 osd1.linux1.l_i_reserved1
262 #define i_frag osd2.linux2.l_i_frag
263 #define i_fsize osd2.linux2.l_i_fsize
264 #define i_reserved2 osd2.linux2.l_i_reserved2
268 #define i_translator osd1.hurd1.h_i_translator
269 #define i_frag osd2.hurd2.h_i_frag;
270 #define i_fsize osd2.hurd2.h_i_fsize;
271 #define i_uid_high osd2.hurd2.h_i_uid_high
272 #define i_gid_high osd2.hurd2.h_i_gid_high
273 #define i_author osd2.hurd2.h_i_author
277 #define i_reserved1 osd1.masix1.m_i_reserved1
278 #define i_frag osd2.masix2.m_i_frag
279 #define i_fsize osd2.masix2.m_i_fsize
280 #define i_reserved2 osd2.masix2.m_i_reserved2
286 #define EXT2_VALID_FS 0x0001 /* Unmounted cleanly */
287 #define EXT2_ERROR_FS 0x0002 /* Errors detected */
292 #define EXT2_MOUNT_CHECK_NORMAL 0x0001 /* Do some more checks */
293 #define EXT2_MOUNT_CHECK_STRICT 0x0002 /* Do again more checks */
294 #define EXT2_MOUNT_CHECK (EXT2_MOUNT_CHECK_NORMAL | \
295 EXT2_MOUNT_CHECK_STRICT)
296 #define EXT2_MOUNT_GRPID 0x0004 /* Create files with directory's group */
297 #define EXT2_MOUNT_DEBUG 0x0008 /* Some debugging messages */
298 #define EXT2_MOUNT_ERRORS_CONT 0x0010 /* Continue on errors */
299 #define EXT2_MOUNT_ERRORS_RO 0x0020 /* Remount fs ro on errors */
300 #define EXT2_MOUNT_ERRORS_PANIC 0x0040 /* Panic on errors */
301 #define EXT2_MOUNT_MINIX_DF 0x0080 /* Mimics the Minix statfs */
303 #define clear_opt(o, opt) o &= ~EXT2_MOUNT_##opt
304 #define set_opt(o, opt) o |= EXT2_MOUNT_##opt
305 #define test_opt(sb, opt) ((sb)->u.ext2_sb.s_mount_opt & \
308 * Maximal mount counts between two filesystem checks
310 #define EXT2_DFL_MAX_MNT_COUNT 20 /* Allow 20 mounts */
311 #define EXT2_DFL_CHECKINTERVAL 0 /* Don't use interval check */
314 * Behaviour when detecting errors
316 #define EXT2_ERRORS_CONTINUE 1 /* Continue execution */
317 #define EXT2_ERRORS_RO 2 /* Remount fs read-only */
318 #define EXT2_ERRORS_PANIC 3 /* Panic */
319 #define EXT2_ERRORS_DEFAULT EXT2_ERRORS_CONTINUE
322 * Structure of the super block
324 struct ext2_super_block {
325 __u32 s_inodes_count; /* Inodes count */
326 __u32 s_blocks_count; /* Blocks count */
327 __u32 s_r_blocks_count; /* Reserved blocks count */
328 __u32 s_free_blocks_count; /* Free blocks count */
329 __u32 s_free_inodes_count; /* Free inodes count */
330 __u32 s_first_data_block; /* First Data Block */
331 __u32 s_log_block_size; /* Block size */
332 __s32 s_log_frag_size; /* Fragment size */
333 __u32 s_blocks_per_group; /* # Blocks per group */
334 __u32 s_frags_per_group; /* # Fragments per group */
335 __u32 s_inodes_per_group; /* # Inodes per group */
336 __u32 s_mtime; /* Mount time */
337 __u32 s_wtime; /* Write time */
338 __u16 s_mnt_count; /* Mount count */
339 __s16 s_max_mnt_count; /* Maximal mount count */
340 __u16 s_magic; /* Magic signature */
341 __u16 s_state; /* File system state */
342 __u16 s_errors; /* Behaviour when detecting errors */
343 __u16 s_minor_rev_level; /* minor revision level */
344 __u32 s_lastcheck; /* time of last check */
345 __u32 s_checkinterval; /* max. time between checks */
346 __u32 s_creator_os; /* OS */
347 __u32 s_rev_level; /* Revision level */
348 __u16 s_def_resuid; /* Default uid for reserved blocks */
349 __u16 s_def_resgid; /* Default gid for reserved blocks */
351 * These fields are for EXT2_DYNAMIC_REV superblocks only.
353 * Note: the difference between the compatible feature set and
354 * the incompatible feature set is that if there is a bit set
355 * in the incompatible feature set that the kernel doesn't
356 * know about, it should refuse to mount the filesystem.
358 * e2fsck's requirements are more strict; if it doesn't know
359 * about a feature in either the compatible or incompatible
360 * feature set, it must abort and not try to meddle with
361 * things it doesn't understand...
363 __u32 s_first_ino; /* First non-reserved inode */
364 __u16 s_inode_size; /* size of inode structure */
365 __u16 s_block_group_nr; /* block group # of this superblock */
366 __u32 s_feature_compat; /* compatible feature set */
367 __u32 s_feature_incompat; /* incompatible feature set */
368 __u32 s_feature_ro_compat; /* readonly-compatible feature set */
369 __u8 s_uuid[16]; /* 128-bit uuid for volume */
370 char s_volume_name[16]; /* volume name */
371 char s_last_mounted[64]; /* directory where last mounted */
372 __u32 s_reserved[206]; /* Padding to the end of the block */
376 * Codes for operating systems
378 #define EXT2_OS_LINUX 0
379 #define EXT2_OS_HURD 1
380 #define EXT2_OS_MASIX 2
381 #define EXT2_OS_FREEBSD 3
382 #define EXT2_OS_LITES 4
387 #define EXT2_GOOD_OLD_REV 0 /* The good old (original) format */
388 #define EXT2_DYNAMIC_REV 1 /* V2 format w/ dynamic inode sizes */
390 #define EXT2_CURRENT_REV EXT2_GOOD_OLD_REV
391 #define EXT2_MAX_SUPP_REV EXT2_DYNAMIC_REV
393 #define EXT2_GOOD_OLD_INODE_SIZE 128
396 * Feature set definitions
399 #define EXT2_FEATURE_RO_COMPAT_SPARSE_SUPER 0x0001
401 #define EXT2_FEATURE_COMPAT_SUPP 0
402 #define EXT2_FEATURE_INCOMPAT_SUPP 0
403 #define EXT2_FEATURE_RO_COMPAT_SUPP EXT2_FEATURE_RO_COMPAT_SPARSE_SUPER
406 * Default values for user and/or group using reserved blocks
408 #define EXT2_DEF_RESUID 0
409 #define EXT2_DEF_RESGID 0
412 * Structure of a directory entry
414 #define EXT2_NAME_LEN 255
416 struct ext2_dir_entry {
417 __u32 inode; /* Inode number */
418 __u16 rec_len; /* Directory entry length */
419 __u16 name_len; /* Name length */
420 char name[EXT2_NAME_LEN]; /* File name */
424 * EXT2_DIR_PAD defines the directory entries boundaries
426 * NOTE: It must be a multiple of 4
428 #define EXT2_DIR_PAD 4
429 #define EXT2_DIR_ROUND (EXT2_DIR_PAD - 1)
430 #define EXT2_DIR_REC_LEN(name_len) (((name_len) + 8 + EXT2_DIR_ROUND) & \
435 * Function prototypes
439 * Ok, these declarations are also in <linux/kernel.h> but none of the
440 * ext2 source programs needs to include it so they are duplicated here.
442 #if __GNUC__ < 2 || (__GNUC__ == 2 && __GNUC_MINOR__ < 5)
443 # define NORET_TYPE __volatile__
444 # define ATTRIB_NORET /**/
445 # define NORET_AND /**/
447 # define NORET_TYPE /**/
448 # define ATTRIB_NORET __attribute__((noreturn))
449 # define NORET_AND noreturn,
453 extern int ext2_permission (struct inode *, int);
456 extern int ext2_new_block (const struct inode *, unsigned long,
457 __u32 *, __u32 *, int *);
458 extern void ext2_free_blocks (const struct inode *, unsigned long,
460 extern unsigned long ext2_count_free_blocks (struct super_block *);
461 extern void ext2_check_blocks_bitmap (struct super_block *);
464 extern unsigned long ext2_count_free (struct buffer_head *, unsigned);
467 extern int ext2_check_dir_entry (const char *, struct inode *,
468 struct ext2_dir_entry *, struct buffer_head *,
472 extern int ext2_read (struct inode *, struct file *, char *, int);
473 extern int ext2_write (struct inode *, struct file *, char *, int);
476 extern int ext2_sync_file (struct inode *, struct file *);
479 extern struct inode * ext2_new_inode (const struct inode *, int, int *);
480 extern void ext2_free_inode (struct inode *);
481 extern unsigned long ext2_count_free_inodes (struct super_block *);
482 extern void ext2_check_inodes_bitmap (struct super_block *);
485 extern int ext2_bmap (struct inode *, int);
487 extern struct buffer_head * ext2_getblk (struct inode *, long, int, int *);
488 extern struct buffer_head * ext2_bread (struct inode *, int, int, int *);
490 extern int ext2_getcluster (struct inode * inode, long block);
491 extern void ext2_read_inode (struct inode *);
492 extern void ext2_write_inode (struct inode *);
493 extern void ext2_put_inode (struct inode *);
494 extern int ext2_sync_inode (struct inode *);
495 extern void ext2_discard_prealloc (struct inode *);
498 extern int ext2_ioctl (struct inode *, struct file *, unsigned int,
502 extern void ext2_release (struct inode *, struct file *);
503 extern int ext2_lookup (struct inode *,const char *, int, struct inode **);
504 extern int ext2_create (struct inode *,const char *, int, int,
506 extern int ext2_mkdir (struct inode *, const char *, int, int);
507 extern int ext2_rmdir (struct inode *, const char *, int);
508 extern int ext2_unlink (struct inode *, const char *, int);
509 extern int ext2_symlink (struct inode *, const char *, int, const char *);
510 extern int ext2_link (struct inode *, struct inode *, const char *, int);
511 extern int ext2_mknod (struct inode *, const char *, int, int, int);
512 extern int ext2_rename (struct inode *, const char *, int,
513 struct inode *, const char *, int, int);
516 extern void ext2_error (struct super_block *, const char *, const char *, ...)
517 __attribute__ ((format (printf, 3, 4)));
518 extern NORET_TYPE void ext2_panic (struct super_block *, const char *,
520 __attribute__ ((NORET_AND format (printf, 3, 4)));
521 extern void ext2_warning (struct super_block *, const char *, const char *, ...)
522 __attribute__ ((format (printf, 3, 4)));
523 extern void ext2_put_super (struct super_block *);
524 extern void ext2_write_super (struct super_block *);
525 extern int ext2_remount (struct super_block *, int *, char *);
526 extern struct super_block * ext2_read_super (struct super_block *,void *,int);
527 extern int init_ext2_fs(void);
528 extern void ext2_statfs (struct super_block *, struct statfs *, int);
531 extern void ext2_truncate (struct inode *);
534 * Inodes and files operations
538 extern struct inode_operations ext2_dir_inode_operations;
541 extern struct inode_operations ext2_file_inode_operations;
544 extern struct inode_operations ext2_symlink_inode_operations;
546 #endif /* __KERNEL__ */
548 #endif /* _LINUX_EXT2_FS_H */