ext2_fs.h revision df614db6ef79c767745b8154c26d69398b571605
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 <ext2fs/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 inodes 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/*
63 * Maximal count of links to a file
64 */
65#define EXT2_LINK_MAX		32000
66
67/*
68 * Macro-instructions used to manage several block sizes
69 */
70#define EXT2_MIN_BLOCK_SIZE		1024
71#define	EXT2_MAX_BLOCK_SIZE		4096
72#define EXT2_MIN_BLOCK_LOG_SIZE		  10
73#ifdef __KERNEL__
74# define EXT2_BLOCK_SIZE(s)		((s)->s_blocksize)
75#else
76# define EXT2_BLOCK_SIZE(s)		(EXT2_MIN_BLOCK_SIZE << (s)->s_log_block_size)
77#endif
78#define EXT2_ACLE_PER_BLOCK(s)		(EXT2_BLOCK_SIZE(s) / sizeof (struct ext2_acl_entry))
79#define	EXT2_ADDR_PER_BLOCK(s)		(EXT2_BLOCK_SIZE(s) / sizeof (__u32))
80#ifdef __KERNEL__
81# define EXT2_BLOCK_SIZE_BITS(s)	((s)->s_blocksize_bits)
82#else
83# define EXT2_BLOCK_SIZE_BITS(s)	((s)->s_log_block_size + 10)
84#endif
85#ifdef __KERNEL__
86#define	EXT2_ADDR_PER_BLOCK_BITS(s)	((s)->u.ext2_sb.s_addr_per_block_bits)
87#define EXT2_INODE_SIZE(s)		((s)->u.ext2_sb.s_inode_size)
88#define EXT2_FIRST_INO(s)		((s)->u.ext2_sb.s_first_ino)
89#else
90#define EXT2_INODE_SIZE(s)	(((s)->s_rev_level == EXT2_GOOD_OLD_REV) ? \
91				 EXT2_GOOD_OLD_INODE_SIZE : \
92				 (s)->s_inode_size)
93#define EXT2_FIRST_INO(s)	(((s)->s_rev_level == EXT2_GOOD_OLD_REV) ? \
94				 EXT2_GOOD_OLD_FIRST_INO : \
95				 (s)->s_first_ino)
96#endif
97
98/*
99 * Macro-instructions used to manage fragments
100 */
101#define EXT2_MIN_FRAG_SIZE		1024
102#define	EXT2_MAX_FRAG_SIZE		4096
103#define EXT2_MIN_FRAG_LOG_SIZE		  10
104#ifdef __KERNEL__
105# define EXT2_FRAG_SIZE(s)		((s)->u.ext2_sb.s_frag_size)
106# define EXT2_FRAGS_PER_BLOCK(s)	((s)->u.ext2_sb.s_frags_per_block)
107#else
108# define EXT2_FRAG_SIZE(s)		(EXT2_MIN_FRAG_SIZE << (s)->s_log_frag_size)
109# define EXT2_FRAGS_PER_BLOCK(s)	(EXT2_BLOCK_SIZE(s) / EXT2_FRAG_SIZE(s))
110#endif
111
112/*
113 * ACL structures
114 */
115struct ext2_acl_header	/* Header of Access Control Lists */
116{
117	__u32	aclh_size;
118	__u32	aclh_file_count;
119	__u32	aclh_acle_count;
120	__u32	aclh_first_acle;
121};
122
123struct ext2_acl_entry	/* Access Control List Entry */
124{
125	__u32	acle_size;
126	__u16	acle_perms;	/* Access permissions */
127	__u16	acle_type;	/* Type of entry */
128	__u16	acle_tag;	/* User or group identity */
129	__u16	acle_pad1;
130	__u32	acle_next;	/* Pointer on next entry for the */
131					/* same inode or on next free entry */
132};
133
134/*
135 * Structure of a blocks group descriptor
136 */
137struct ext2_group_desc
138{
139	__u32	bg_block_bitmap;		/* Blocks bitmap block */
140	__u32	bg_inode_bitmap;		/* Inodes bitmap block */
141	__u32	bg_inode_table;		/* Inodes table block */
142	__u16	bg_free_blocks_count;	/* Free blocks count */
143	__u16	bg_free_inodes_count;	/* Free inodes count */
144	__u16	bg_used_dirs_count;	/* Directories count */
145	__u16	bg_pad;
146	__u32	bg_reserved[3];
147};
148
149/*
150 * Data structures used by the directory indexing feature
151 *
152 * Note: all of the multibyte integer fields are little endian.
153 */
154
155/*
156 * Note: dx_root_info is laid out so that if it should somehow get
157 * overlaid by a dirent the two low bits of the hash version will be
158 * zero.  Therefore, the hash version mod 4 should never be 0.
159 * Sincerely, the paranoia department.
160 */
161struct ext2_dx_root_info {
162	__u32 reserved_zero;
163	__u8 hash_version; /* 0 now, 1 at release */
164	__u8 info_length; /* 8 */
165	__u8 indirect_levels;
166	__u8 unused_flags;
167};
168
169struct ext2_dx_entry {
170	__u32 hash;
171	__u32 block;
172};
173
174struct ext2_dx_countlimit {
175	__u16 limit;
176	__u16 count;
177};
178
179
180/*
181 * Macro-instructions used to manage group descriptors
182 */
183#ifdef __KERNEL__
184# define EXT2_BLOCKS_PER_GROUP(s)	((s)->u.ext2_sb.s_blocks_per_group)
185# define EXT2_DESC_PER_BLOCK(s)		((s)->u.ext2_sb.s_desc_per_block)
186# define EXT2_INODES_PER_GROUP(s)	((s)->u.ext2_sb.s_inodes_per_group)
187# define EXT2_DESC_PER_BLOCK_BITS(s)	((s)->u.ext2_sb.s_desc_per_block_bits)
188#else
189# define EXT2_BLOCKS_PER_GROUP(s)	((s)->s_blocks_per_group)
190# define EXT2_DESC_PER_BLOCK(s)		(EXT2_BLOCK_SIZE(s) / sizeof (struct ext2_group_desc))
191# define EXT2_INODES_PER_GROUP(s)	((s)->s_inodes_per_group)
192#endif
193
194/*
195 * Constants relative to the data blocks
196 */
197#define	EXT2_NDIR_BLOCKS		12
198#define	EXT2_IND_BLOCK			EXT2_NDIR_BLOCKS
199#define	EXT2_DIND_BLOCK			(EXT2_IND_BLOCK + 1)
200#define	EXT2_TIND_BLOCK			(EXT2_DIND_BLOCK + 1)
201#define	EXT2_N_BLOCKS			(EXT2_TIND_BLOCK + 1)
202
203/*
204 * Inode flags
205 */
206#define	EXT2_SECRM_FL			0x00000001 /* Secure deletion */
207#define	EXT2_UNRM_FL			0x00000002 /* Undelete */
208#define	EXT2_COMPR_FL			0x00000004 /* Compress file */
209#define EXT2_SYNC_FL			0x00000008 /* Synchronous updates */
210#define EXT2_IMMUTABLE_FL		0x00000010 /* Immutable file */
211#define EXT2_APPEND_FL			0x00000020 /* writes to file may only append */
212#define EXT2_NODUMP_FL			0x00000040 /* do not dump file */
213#define EXT2_NOATIME_FL			0x00000080 /* do not update atime */
214/* Reserved for compression usage... */
215#define EXT2_DIRTY_FL			0x00000100
216#define EXT2_COMPRBLK_FL		0x00000200 /* One or more compressed clusters */
217#define EXT2_NOCOMPR_FL 		0x00000400 /* Access raw compressed data */
218#define EXT2_ECOMPR_FL			0x00000800 /* Compression error */
219/* End compression flags --- maybe not all used */
220#define EXT2_BTREE_FL			0x00001000 /* btree format dir */
221#define EXT2_INDEX_FL			0x00001000 /* hash-indexed directory */
222#define EXT2_IMAGIC_FL			0x00002000
223#define EXT3_JOURNAL_DATA_FL		0x00004000 /* file data should be journaled */
224#define EXT2_NOTAIL_FL			0x00008000 /* file tail should not be merged */
225#define EXT2_RESERVED_FL		0x80000000 /* reserved for ext2 lib */
226
227#define EXT2_FL_USER_VISIBLE		0x0000DFFF /* User visible flags */
228#define EXT2_FL_USER_MODIFIABLE		0x000080FF /* User modifiable flags */
229
230/*
231 * ioctl commands
232 */
233#define	EXT2_IOC_GETFLAGS		_IOR('f', 1, long)
234#define	EXT2_IOC_SETFLAGS		_IOW('f', 2, long)
235#define	EXT2_IOC_GETVERSION		_IOR('v', 1, long)
236#define	EXT2_IOC_SETVERSION		_IOW('v', 2, long)
237
238/*
239 * Structure of an inode on the disk
240 */
241struct ext2_inode {
242	__u16	i_mode;		/* File mode */
243	__u16	i_uid;		/* Low 16 bits of Owner Uid */
244	__u32	i_size;		/* Size in bytes */
245	__u32	i_atime;	/* Access time */
246	__u32	i_ctime;	/* Creation time */
247	__u32	i_mtime;	/* Modification time */
248	__u32	i_dtime;	/* Deletion Time */
249	__u16	i_gid;		/* Low 16 bits of Group Id */
250	__u16	i_links_count;	/* Links count */
251	__u32	i_blocks;	/* Blocks count */
252	__u32	i_flags;	/* File flags */
253	union {
254		struct {
255			__u32  l_i_reserved1;
256		} linux1;
257		struct {
258			__u32  h_i_translator;
259		} hurd1;
260		struct {
261			__u32  m_i_reserved1;
262		} masix1;
263	} osd1;				/* OS dependent 1 */
264	__u32	i_block[EXT2_N_BLOCKS];/* Pointers to blocks */
265	__u32	i_generation;	/* File version (for NFS) */
266	__u32	i_file_acl;	/* File ACL */
267	__u32	i_dir_acl;	/* Directory ACL */
268	__u32	i_faddr;	/* Fragment address */
269	union {
270		struct {
271			__u8	l_i_frag;	/* Fragment number */
272			__u8	l_i_fsize;	/* Fragment size */
273			__u16	i_pad1;
274			__u16	l_i_uid_high;	/* these 2 fields    */
275			__u16	l_i_gid_high;	/* were reserved2[0] */
276			__u32	l_i_reserved2;
277		} linux2;
278		struct {
279			__u8	h_i_frag;	/* Fragment number */
280			__u8	h_i_fsize;	/* Fragment size */
281			__u16	h_i_mode_high;
282			__u16	h_i_uid_high;
283			__u16	h_i_gid_high;
284			__u32	h_i_author;
285		} hurd2;
286		struct {
287			__u8	m_i_frag;	/* Fragment number */
288			__u8	m_i_fsize;	/* Fragment size */
289			__u16	m_pad1;
290			__u32	m_i_reserved2[2];
291		} masix2;
292	} osd2;				/* OS dependent 2 */
293};
294
295#define i_size_high	i_dir_acl
296
297#if defined(__KERNEL__) || defined(__linux__)
298#define i_reserved1	osd1.linux1.l_i_reserved1
299#define i_frag		osd2.linux2.l_i_frag
300#define i_fsize		osd2.linux2.l_i_fsize
301#define i_uid_low	i_uid
302#define i_gid_low	i_gid
303#define i_uid_high	osd2.linux2.l_i_uid_high
304#define i_gid_high	osd2.linux2.l_i_gid_high
305#define i_reserved2	osd2.linux2.l_i_reserved2
306
307#elif defined(__GNU__)
308
309#define i_translator	osd1.hurd1.h_i_translator
310#define i_frag		osd2.hurd2.h_i_frag;
311#define i_fsize		osd2.hurd2.h_i_fsize;
312#define i_uid_high	osd2.hurd2.h_i_uid_high
313#define i_gid_high	osd2.hurd2.h_i_gid_high
314#define i_author	osd2.hurd2.h_i_author
315
316#elif defined(__masix__)
317
318#define i_reserved1	osd1.masix1.m_i_reserved1
319#define i_frag		osd2.masix2.m_i_frag
320#define i_fsize		osd2.masix2.m_i_fsize
321#define i_reserved2	osd2.masix2.m_i_reserved2
322
323#endif	/* defined(__KERNEL) || defined(__linux__) */
324
325/*
326 * File system states
327 */
328#define	EXT2_VALID_FS			0x0001	/* Unmounted cleanly */
329#define	EXT2_ERROR_FS			0x0002	/* Errors detected */
330
331/*
332 * Mount flags
333 */
334#define EXT2_MOUNT_CHECK		0x0001	/* Do mount-time checks */
335#define EXT2_MOUNT_GRPID		0x0004	/* Create files with directory's group */
336#define EXT2_MOUNT_DEBUG		0x0008	/* Some debugging messages */
337#define EXT2_MOUNT_ERRORS_CONT		0x0010	/* Continue on errors */
338#define EXT2_MOUNT_ERRORS_RO		0x0020	/* Remount fs ro on errors */
339#define EXT2_MOUNT_ERRORS_PANIC		0x0040	/* Panic on errors */
340#define EXT2_MOUNT_MINIX_DF		0x0080	/* Mimics the Minix statfs */
341#define EXT2_MOUNT_NO_UID32		0x0200  /* Disable 32-bit UIDs */
342
343#define clear_opt(o, opt)		o &= ~EXT2_MOUNT_##opt
344#define set_opt(o, opt)			o |= EXT2_MOUNT_##opt
345#define test_opt(sb, opt)		((sb)->u.ext2_sb.s_mount_opt & \
346					 EXT2_MOUNT_##opt)
347/*
348 * Maximal mount counts between two filesystem checks
349 */
350#define EXT2_DFL_MAX_MNT_COUNT		20	/* Allow 20 mounts */
351#define EXT2_DFL_CHECKINTERVAL		0	/* Don't use interval check */
352
353/*
354 * Behaviour when detecting errors
355 */
356#define EXT2_ERRORS_CONTINUE		1	/* Continue execution */
357#define EXT2_ERRORS_RO			2	/* Remount fs read-only */
358#define EXT2_ERRORS_PANIC		3	/* Panic */
359#define EXT2_ERRORS_DEFAULT		EXT2_ERRORS_CONTINUE
360
361/*
362 * Structure of the super block
363 */
364struct ext2_super_block {
365	__u32	s_inodes_count;		/* Inodes count */
366	__u32	s_blocks_count;		/* Blocks count */
367	__u32	s_r_blocks_count;	/* Reserved blocks count */
368	__u32	s_free_blocks_count;	/* Free blocks count */
369	__u32	s_free_inodes_count;	/* Free inodes count */
370	__u32	s_first_data_block;	/* First Data Block */
371	__u32	s_log_block_size;	/* Block size */
372	__s32	s_log_frag_size;	/* Fragment size */
373	__u32	s_blocks_per_group;	/* # Blocks per group */
374	__u32	s_frags_per_group;	/* # Fragments per group */
375	__u32	s_inodes_per_group;	/* # Inodes per group */
376	__u32	s_mtime;		/* Mount time */
377	__u32	s_wtime;		/* Write time */
378	__u16	s_mnt_count;		/* Mount count */
379	__s16	s_max_mnt_count;	/* Maximal mount count */
380	__u16	s_magic;		/* Magic signature */
381	__u16	s_state;		/* File system state */
382	__u16	s_errors;		/* Behaviour when detecting errors */
383	__u16	s_minor_rev_level; 	/* minor revision level */
384	__u32	s_lastcheck;		/* time of last check */
385	__u32	s_checkinterval;	/* max. time between checks */
386	__u32	s_creator_os;		/* OS */
387	__u32	s_rev_level;		/* Revision level */
388	__u16	s_def_resuid;		/* Default uid for reserved blocks */
389	__u16	s_def_resgid;		/* Default gid for reserved blocks */
390	/*
391	 * These fields are for EXT2_DYNAMIC_REV superblocks only.
392	 *
393	 * Note: the difference between the compatible feature set and
394	 * the incompatible feature set is that if there is a bit set
395	 * in the incompatible feature set that the kernel doesn't
396	 * know about, it should refuse to mount the filesystem.
397	 *
398	 * e2fsck's requirements are more strict; if it doesn't know
399	 * about a feature in either the compatible or incompatible
400	 * feature set, it must abort and not try to meddle with
401	 * things it doesn't understand...
402	 */
403	__u32	s_first_ino; 		/* First non-reserved inode */
404	__u16   s_inode_size; 		/* size of inode structure */
405	__u16	s_block_group_nr; 	/* block group # of this superblock */
406	__u32	s_feature_compat; 	/* compatible feature set */
407	__u32	s_feature_incompat; 	/* incompatible feature set */
408	__u32	s_feature_ro_compat; 	/* readonly-compatible feature set */
409	__u8	s_uuid[16];		/* 128-bit uuid for volume */
410	char	s_volume_name[16]; 	/* volume name */
411	char	s_last_mounted[64]; 	/* directory where last mounted */
412	__u32	s_algorithm_usage_bitmap; /* For compression */
413	/*
414	 * Performance hints.  Directory preallocation should only
415	 * happen if the EXT2_FEATURE_COMPAT_DIR_PREALLOC flag is on.
416	 */
417	__u8	s_prealloc_blocks;	/* Nr of blocks to try to preallocate*/
418	__u8	s_prealloc_dir_blocks;	/* Nr to preallocate for dirs */
419	__u16	s_padding1;
420	/*
421	 * Journaling support valid if EXT2_FEATURE_COMPAT_HAS_JOURNAL set.
422	 */
423	__u8	s_journal_uuid[16];	/* uuid of journal superblock */
424	__u32	s_journal_inum;		/* inode number of journal file */
425	__u32	s_journal_dev;		/* device number of journal file */
426	__u32	s_last_orphan;		/* start of list of inodes to delete */
427
428	__u32	s_reserved[197];	/* Padding to the end of the block */
429};
430
431#ifdef __KERNEL__
432#define EXT2_SB(sb)	(&((sb)->u.ext2_sb))
433#else
434/* Assume that user mode programs are passing in an ext2fs superblock, not
435 * a kernel struct super_block.  This will allow us to call the feature-test
436 * macros from user land. */
437#define EXT2_SB(sb)	(sb)
438#endif
439
440/*
441 * Codes for operating systems
442 */
443#define EXT2_OS_LINUX		0
444#define EXT2_OS_HURD		1
445#define EXT2_OS_MASIX		2
446#define EXT2_OS_FREEBSD		3
447#define EXT2_OS_LITES		4
448
449/*
450 * Revision levels
451 */
452#define EXT2_GOOD_OLD_REV	0	/* The good old (original) format */
453#define EXT2_DYNAMIC_REV	1 	/* V2 format w/ dynamic inode sizes */
454
455#define EXT2_CURRENT_REV	EXT2_GOOD_OLD_REV
456#define EXT2_MAX_SUPP_REV	EXT2_DYNAMIC_REV
457
458#define EXT2_GOOD_OLD_INODE_SIZE 128
459
460/*
461 * Feature set definitions
462 */
463
464#define EXT2_HAS_COMPAT_FEATURE(sb,mask)			\
465	( EXT2_SB(sb)->s_feature_compat & (mask) )
466#define EXT2_HAS_RO_COMPAT_FEATURE(sb,mask)			\
467	( EXT2_SB(sb)->s_feature_ro_compat & (mask) )
468#define EXT2_HAS_INCOMPAT_FEATURE(sb,mask)			\
469	( EXT2_SB(sb)->s_feature_incompat & (mask) )
470
471#define EXT2_FEATURE_COMPAT_DIR_PREALLOC	0x0001
472#define EXT2_FEATURE_COMPAT_IMAGIC_INODES	0x0002
473#define EXT3_FEATURE_COMPAT_HAS_JOURNAL		0x0004
474#define EXT2_FEATURE_COMPAT_EXT_ATTR		0x0008
475#define EXT2_FEATURE_COMPAT_RESIZE_INODE	0x0010
476#define EXT2_FEATURE_COMPAT_DIR_INDEX		0x0020
477
478#define EXT2_FEATURE_RO_COMPAT_SPARSE_SUPER	0x0001
479#define EXT2_FEATURE_RO_COMPAT_LARGE_FILE	0x0002
480#define EXT2_FEATURE_RO_COMPAT_BTREE_DIR	0x0004
481
482#define EXT2_FEATURE_INCOMPAT_COMPRESSION	0x0001
483#define EXT2_FEATURE_INCOMPAT_FILETYPE		0x0002
484#define EXT3_FEATURE_INCOMPAT_RECOVER		0x0004 /* Needs recovery */
485#define EXT3_FEATURE_INCOMPAT_JOURNAL_DEV	0x0008 /* Journal device */
486
487#define EXT2_FEATURE_COMPAT_SUPP	0
488#define EXT2_FEATURE_INCOMPAT_SUPP	EXT2_FEATURE_INCOMPAT_FILETYPE
489#define EXT2_FEATURE_RO_COMPAT_SUPP	(EXT2_FEATURE_RO_COMPAT_SPARSE_SUPER| \
490					 EXT2_FEATURE_RO_COMPAT_LARGE_FILE| \
491					 EXT2_FEATURE_RO_COMPAT_BTREE_DIR)
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 * Structure of a directory entry
501 */
502#define EXT2_NAME_LEN 255
503
504struct ext2_dir_entry {
505	__u32	inode;			/* Inode number */
506	__u16	rec_len;		/* Directory entry length */
507	__u16	name_len;		/* Name length */
508	char	name[EXT2_NAME_LEN];	/* File name */
509};
510
511/*
512 * The new version of the directory entry.  Since EXT2 structures are
513 * stored in intel byte order, and the name_len field could never be
514 * bigger than 255 chars, it's safe to reclaim the extra byte for the
515 * file_type field.
516 */
517struct ext2_dir_entry_2 {
518	__u32	inode;			/* Inode number */
519	__u16	rec_len;		/* Directory entry length */
520	__u8	name_len;		/* Name length */
521	__u8	file_type;
522	char	name[EXT2_NAME_LEN];	/* File name */
523};
524
525/*
526 * Ext2 directory file types.  Only the low 3 bits are used.  The
527 * other bits are reserved for now.
528 */
529#define EXT2_FT_UNKNOWN		0
530#define EXT2_FT_REG_FILE	1
531#define EXT2_FT_DIR		2
532#define EXT2_FT_CHRDEV		3
533#define EXT2_FT_BLKDEV 		4
534#define EXT2_FT_FIFO		5
535#define EXT2_FT_SOCK		6
536#define EXT2_FT_SYMLINK		7
537
538#define EXT2_FT_MAX		8
539
540/*
541 * EXT2_DIR_PAD defines the directory entries boundaries
542 *
543 * NOTE: It must be a multiple of 4
544 */
545#define EXT2_DIR_PAD		 	4
546#define EXT2_DIR_ROUND 			(EXT2_DIR_PAD - 1)
547#define EXT2_DIR_REC_LEN(name_len)	(((name_len) + 8 + EXT2_DIR_ROUND) & \
548					 ~EXT2_DIR_ROUND)
549
550#ifdef __KERNEL__
551/*
552 * Function prototypes
553 */
554
555/*
556 * Ok, these declarations are also in <linux/kernel.h> but none of the
557 * ext2 source programs needs to include it so they are duplicated here.
558 */
559# define NORET_TYPE    /**/
560# define ATTRIB_NORET  __attribute__((noreturn))
561# define NORET_AND     noreturn,
562
563/* acl.c */
564extern int ext2_permission (struct inode *, int);
565
566/* balloc.c */
567extern int ext2_bg_has_super(struct super_block *sb, int group);
568extern unsigned long ext2_bg_num_gdb(struct super_block *sb, int group);
569extern int ext2_new_block (const struct inode *, unsigned long,
570			   __u32 *, __u32 *, int *);
571extern void ext2_free_blocks (const struct inode *, unsigned long,
572			      unsigned long);
573extern unsigned long ext2_count_free_blocks (struct super_block *);
574extern void ext2_check_blocks_bitmap (struct super_block *);
575extern struct ext2_group_desc * ext2_get_group_desc(struct super_block * sb,
576						    unsigned int block_group,
577						    struct buffer_head ** bh);
578
579/* bitmap.c */
580extern unsigned long ext2_count_free (struct buffer_head *, unsigned);
581
582/* dir.c */
583extern int ext2_check_dir_entry (const char *, struct inode *,
584				 struct ext2_dir_entry_2 *, struct buffer_head *,
585				 unsigned long);
586
587/* file.c */
588extern int ext2_read (struct inode *, struct file *, char *, int);
589extern int ext2_write (struct inode *, struct file *, char *, int);
590
591/* fsync.c */
592extern int ext2_sync_file (struct file *, struct dentry *, int);
593extern int ext2_fsync_inode (struct inode *, int);
594
595/* ialloc.c */
596extern struct inode * ext2_new_inode (const struct inode *, int);
597extern void ext2_free_inode (struct inode *);
598extern unsigned long ext2_count_free_inodes (struct super_block *);
599extern void ext2_check_inodes_bitmap (struct super_block *);
600
601/* inode.c */
602
603extern struct buffer_head * ext2_getblk (struct inode *, long, int, int *);
604extern struct buffer_head * ext2_bread (struct inode *, int, int, int *);
605
606extern void ext2_read_inode (struct inode *);
607extern void ext2_write_inode (struct inode *, int);
608extern void ext2_put_inode (struct inode *);
609extern void ext2_delete_inode (struct inode *);
610extern int ext2_sync_inode (struct inode *);
611extern void ext2_discard_prealloc (struct inode *);
612
613/* ioctl.c */
614extern int ext2_ioctl (struct inode *, struct file *, unsigned int,
615		       unsigned long);
616
617/* namei.c */
618extern struct inode_operations ext2_dir_inode_operations;
619
620/* super.c */
621extern void ext2_error (struct super_block *, const char *, const char *, ...)
622	__attribute__ ((format (printf, 3, 4)));
623extern NORET_TYPE void ext2_panic (struct super_block *, const char *,
624				   const char *, ...)
625	__attribute__ ((NORET_AND format (printf, 3, 4)));
626extern void ext2_warning (struct super_block *, const char *, const char *, ...)
627	__attribute__ ((format (printf, 3, 4)));
628extern void ext2_update_dynamic_rev (struct super_block *sb);
629extern void ext2_put_super (struct super_block *);
630extern void ext2_write_super (struct super_block *);
631extern int ext2_remount (struct super_block *, int *, char *);
632extern struct super_block * ext2_read_super (struct super_block *,void *,int);
633extern int ext2_statfs (struct super_block *, struct statfs *);
634
635/* truncate.c */
636extern void ext2_truncate (struct inode *);
637
638/*
639 * Inodes and files operations
640 */
641
642/* dir.c */
643extern struct file_operations ext2_dir_operations;
644
645/* file.c */
646extern struct inode_operations ext2_file_inode_operations;
647extern struct file_operations ext2_file_operations;
648
649/* symlink.c */
650extern struct inode_operations ext2_fast_symlink_inode_operations;
651
652extern struct address_space_operations ext2_aops;
653
654#endif	/* __KERNEL__ */
655
656#endif	/* _LINUX_EXT2_FS_H */
657