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 
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  * Debug code
44  */
45 #ifdef EXT2FS_DEBUG
46 #	define ext2_debug(f, a...)	{ \
47 					printk ("EXT2-fs DEBUG (%s, %d): %s:", \
48 						__FILE__, __LINE__, __FUNCTION__); \
49 				  	printk (f, ## a); \
50 					}
51 #else
52 //#	define ext2_debug(f, a...)	/**/
53 #endif
54 
55 /*
56  * Special inode numbers
57  */
58 #define	EXT2_BAD_INO		 1	/* Bad blocks inode */
59 #define EXT2_ROOT_INO		 2	/* Root inode */
60 #define EXT2_ACL_IDX_INO	 3	/* ACL inode */
61 #define EXT2_ACL_DATA_INO	 4	/* ACL 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 /*
69  * The second extended file system magic number
70  */
71 #define EXT2_SUPER_MAGIC	0xEF53
72 
73 /*
74  * Maximal count of links to a file
75  */
76 #define EXT2_LINK_MAX		32000
77 
78 /*
79  * Macro-instructions used to manage several block sizes
80  */
81 #define EXT2_MIN_BLOCK_SIZE		1024
82 #define	EXT2_MAX_BLOCK_SIZE		4096
83 #define EXT2_MIN_BLOCK_LOG_SIZE 10
84 #ifdef __KERNEL__
85 # define EXT2_BLOCK_SIZE(s)		((s)->s_blocksize)
86 #else
87 # define EXT2_BLOCK_SIZE(s)		(EXT2_MIN_BLOCK_SIZE << (s)->s_log_block_size)
88 #endif
89 #define EXT2_ACLE_PER_BLOCK(s)		(EXT2_BLOCK_SIZE(s) / sizeof (struct ext2_acl_entry))
90 #define	EXT2_ADDR_PER_BLOCK(s)		(EXT2_BLOCK_SIZE(s) / sizeof (__u32))
91 #ifdef __KERNEL__
92 # define EXT2_BLOCK_SIZE_BITS(s)	((s)->s_blocksize_bits)
93 #else
94 # define EXT2_BLOCK_SIZE_BITS(s)	((s)->s_log_block_size + 10)
95 #endif
96 #ifdef __KERNEL__
97 #define	EXT2_ADDR_PER_BLOCK_BITS(s)	((s)->u.ext2_sb.s_addr_per_block_bits)
98 #define EXT2_INODE_SIZE(s)		((s)->u.ext2_sb.s_inode_size)
99 #define EXT2_FIRST_INO(s)		((s)->u.ext2_sb.s_first_ino)
100 #else
101 #define EXT2_INODE_SIZE(s)	(((s)->s_rev_level == EXT2_GOOD_OLD_REV) ? \
102 				 EXT2_GOOD_OLD_INODE_SIZE : \
103 				 (s)->s_inode_size)
104 #define EXT2_FIRST_INO(s)	(((s)->s_rev_level == EXT2_GOOD_OLD_REV) ? \
105 				 EXT2_GOOD_OLD_FIRST_INO : \
106 				 (s)->s_first_ino)
107 #endif
108 
109 /*
110  * Macro-instructions used to manage fragments
111  */
112 #define EXT2_MIN_FRAG_SIZE		1024
113 #define	EXT2_MAX_FRAG_SIZE		4096
114 #define EXT2_MIN_FRAG_LOG_SIZE		  10
115 #ifdef __KERNEL__
116 # define EXT2_FRAG_SIZE(s)		((s)->u.ext2_sb.s_frag_size)
117 # define EXT2_FRAGS_PER_BLOCK(s)	((s)->u.ext2_sb.s_frags_per_block)
118 #else
119 # define EXT2_FRAG_SIZE(s)		(EXT2_MIN_FRAG_SIZE << (s)->s_log_frag_size)
120 # define EXT2_FRAGS_PER_BLOCK(s)	(EXT2_BLOCK_SIZE(s) / EXT2_FRAG_SIZE(s))
121 #endif
122 
123 /*
124  * ACL structures
125  */
126 struct ext2_acl_header	/* Header of Access Control Lists */
127 {
128     __u32	aclh_size;
129     __u32	aclh_file_count;
130     __u32	aclh_acle_count;
131     __u32	aclh_first_acle;
132 };
133 
134 struct ext2_acl_entry	/* Access Control List Entry */
135 {
136     __u32	acle_size;
137     __u16	acle_perms;	/* Access permissions */
138     __u16	acle_type;	/* Type of entry */
139     __u16	acle_tag;	/* User or group identity */
140     __u16	acle_pad1;
141     __u32	acle_next;	/* Pointer on next entry for the */
142     /* same inode or on next free entry */
143 };
144 
145 /*
146  * Structure of a blocks group descriptor
147  */
148 struct ext2_group_desc
149 {
150     __u32	bg_block_bitmap;		/* Blocks bitmap block */
151     __u32	bg_inode_bitmap;		/* Inodes bitmap block */
152     __u32	bg_inode_table;		/* Inodes table block */
153     __u16	bg_free_blocks_count;	/* Free blocks count */
154     __u16	bg_free_inodes_count;	/* Free inodes count */
155     __u16	bg_used_dirs_count;	/* Directories count */
156     __u16	bg_pad;
157     __u32	bg_reserved[3];
158 };
159 
160 /*
161  * Macro-instructions used to manage group descriptors
162  */
163 #ifdef __KERNEL__
164 # define EXT2_BLOCKS_PER_GROUP(s)	((s)->u.ext2_sb.s_blocks_per_group)
165 # define EXT2_DESC_PER_BLOCK(s)		((s)->u.ext2_sb.s_desc_per_block)
166 # define EXT2_INODES_PER_GROUP(s)	((s)->u.ext2_sb.s_inodes_per_group)
167 # define EXT2_DESC_PER_BLOCK_BITS(s)	((s)->u.ext2_sb.s_desc_per_block_bits)
168 #else
169 # define EXT2_BLOCKS_PER_GROUP(s)	((s)->s_blocks_per_group)
170 # define EXT2_DESC_PER_BLOCK(s)		(EXT2_BLOCK_SIZE(s) / sizeof (struct ext2_group_desc))
171 # define EXT2_INODES_PER_GROUP(s)	((s)->s_inodes_per_group)
172 #endif
173 
174 /*
175  * Constants relative to the data blocks
176  */
177 #define	EXT2_NDIR_BLOCKS		12
178 #define	EXT2_IND_BLOCK			EXT2_NDIR_BLOCKS
179 #define	EXT2_DIND_BLOCK			(EXT2_IND_BLOCK + 1)
180 #define	EXT2_TIND_BLOCK			(EXT2_DIND_BLOCK + 1)
181 #define	EXT2_N_BLOCKS			(EXT2_TIND_BLOCK + 1)
182 
183 /*
184  * Inode flags
185  */
186 #define	EXT2_SECRM_FL			0x00000001 /* Secure deletion */
187 #define	EXT2_UNRM_FL			0x00000002 /* Undelete */
188 #define	EXT2_COMPR_FL			0x00000004 /* Compress file */
189 #define EXT2_SYNC_FL			0x00000008 /* Synchronous updates */
190 #define EXT2_IMMUTABLE_FL		0x00000010 /* Immutable file */
191 #define EXT2_APPEND_FL			0x00000020 /* writes to file may only append */
192 #define EXT2_NODUMP_FL			0x00000040 /* do not dump file */
193 #define EXT2_NOATIME_FL			0x00000080 /* do not update atime */
194 /* Reserved for compression usage... */
195 #define EXT2_DIRTY_FL			0x00000100
196 #define EXT2_COMPRBLK_FL		0x00000200 /* One or more compressed clusters */
197 #define EXT2_NOCOMP_FL			0x00000400 /* Don't compress */
198 #define EXT2_ECOMPR_FL			0x00000800 /* Compression error */
199 /* End compression flags --- maybe not all used */
200 #define EXT2_BTREE_FL           0x00001000 /* btree format dir */
201 #define EXT2_IMAGIC_FL          0x00002000 /* AFS directory */
202 #define EXT2_JOURNAL_DATA_FL    0x00004000 /* file data should be journaled */
203 #define EXT2_NOTAIL_FL          0x00008000 /* file tail should not be merged */
204 #define EXT2_DIRSYNC_FL         0x00010000 /* dirsync behaviour (directories only) */
205 #define EXT2_TOPDIR_FL          0x00020000 /* Top of directory hierarchies*/
206 #define EXT2_HUGE_FILE_FL       0x00040000 /* Set to each huge file */
207 #define EXT2_EXTENTS_FL         0x00080000 /* Inode uses extents */
208 #define EXT2_RESERVED_FL        0x80000000 /* reserved for ext2 lib */
209 
210 #define EXT2_FL_USER_VISIBLE		0x00001FFF /* User visible flags */
211 #define EXT2_FL_USER_MODIFIABLE		0x000000FF /* User modifiable flags */
212 
213 /*
214  * ioctl commands
215  */
216 #define	EXT2_IOC_GETFLAGS		_IOR('f', 1, long)
217 #define	EXT2_IOC_SETFLAGS		_IOW('f', 2, long)
218 #define	EXT2_IOC_GETVERSION		_IOR('v', 1, long)
219 #define	EXT2_IOC_SETVERSION		_IOW('v', 2, long)
220 
221 /*
222  * Structure of an inode on the disk
223  */
224 struct ext2_inode {
225     __u16	i_mode;		/* File mode */
226     __u16	i_uid;		/* Low 16 bits of Owner Uid */
227     __u32	i_size;		/* Size in bytes */
228     __u32	i_atime;	/* Access time */
229     __u32	i_ctime;	/* Creation time */
230     __u32	i_mtime;	/* Modification time */
231     __u32	i_dtime;	/* Deletion Time */
232     __u16	i_gid;		/* Low 16 bits of Group Id */
233     __u16	i_links_count;	/* Links count */
234     __u32	i_blocks;	/* Blocks count */
235     __u32	i_flags;	/* File flags */
236     union {
237         struct {
238             __u32  l_i_reserved1;
239         } linux1;
240         struct {
241             __u32  h_i_translator;
242         } hurd1;
243         struct {
244             __u32  m_i_reserved1;
245         } masix1;
246     } osd1;				/* OS dependent 1 */
247     __u32	i_block[EXT2_N_BLOCKS];/* Pointers to blocks */
248     __u32	i_generation;	/* File version (for NFS) */
249     __u32	i_file_acl;	/* File ACL */
250     __u32	i_dir_acl;	/* Directory ACL */
251     __u32	i_faddr;	/* Fragment address */
252     union {
253         struct {
254             __u8	l_i_frag;	/* Fragment number */
255             __u8	l_i_fsize;	/* Fragment size */
256             __u16	i_pad1;
257             __u16	l_i_uid_high;	/* these 2 fields    */
258             __u16	l_i_gid_high;	/* were reserved2[0] */
259             __u32	l_i_reserved2;
260         } linux2;
261         struct {
262             __u8	h_i_frag;	/* Fragment number */
263             __u8	h_i_fsize;	/* Fragment size */
264             __u16	h_i_mode_high;
265             __u16	h_i_uid_high;
266             __u16	h_i_gid_high;
267             __u32	h_i_author;
268         } hurd2;
269         struct {
270             __u8	m_i_frag;	/* Fragment number */
271             __u8	m_i_fsize;	/* Fragment size */
272             __u16	m_pad1;
273             __u32	m_i_reserved2[2];
274         } masix2;
275     } osd2;				/* OS dependent 2 */
276     __le16	i_extra_isize;
277     __le16	i_pad1;
278 };
279 
280 #if defined(__KERNEL__) || defined(__linux__)
281 #define i_reserved1	osd1.linux1.l_i_reserved1
282 #define i_frag		osd2.linux2.l_i_frag
283 #define i_fsize		osd2.linux2.l_i_fsize
284 #define i_uid_low	i_uid
285 #define i_gid_low	i_gid
286 #define i_uid_high	osd2.linux2.l_i_uid_high
287 #define i_gid_high	osd2.linux2.l_i_gid_high
288 #define i_reserved2	osd2.linux2.l_i_reserved2
289 #endif
290 
291 #ifdef	__hurd__
292 #define i_translator	osd1.hurd1.h_i_translator
293 #define i_frag		osd2.hurd2.h_i_frag;
294 #define i_fsize		osd2.hurd2.h_i_fsize;
295 #define i_uid_high	osd2.hurd2.h_i_uid_high
296 #define i_gid_high	osd2.hurd2.h_i_gid_high
297 #define i_author	osd2.hurd2.h_i_author
298 #endif
299 
300 #ifdef	__masix__
301 #define i_reserved1	osd1.masix1.m_i_reserved1
302 #define i_frag		osd2.masix2.m_i_frag
303 #define i_fsize		osd2.masix2.m_i_fsize
304 #define i_reserved2	osd2.masix2.m_i_reserved2
305 #endif
306 
307 /*
308  * File system states
309  */
310 #define	EXT2_VALID_FS			0x0001	/* Unmounted cleanly */
311 #define	EXT2_ERROR_FS			0x0002	/* Errors detected */
312 
313 /*
314  * Mount flags
315  */
316 #define EXT2_MOUNT_CHECK		0x0001	/* Do mount-time checks */
317 #define EXT2_MOUNT_GRPID		0x0004	/* Create files with directory's group */
318 #define EXT2_MOUNT_DEBUG		0x0008	/* Some debugging messages */
319 #define EXT2_MOUNT_ERRORS_CONT		0x0010	/* Continue on errors */
320 #define EXT2_MOUNT_ERRORS_RO		0x0020	/* Remount fs ro on errors */
321 #define EXT2_MOUNT_ERRORS_PANIC		0x0040	/* Panic on errors */
322 #define EXT2_MOUNT_MINIX_DF		0x0080	/* Mimics the Minix statfs */
323 #define EXT2_MOUNT_NO_UID32		0x0200  /* Disable 32-bit UIDs */
324 
325 #define clear_opt(o, opt)		o &= ~EXT2_MOUNT_##opt
326 #define set_opt(o, opt)			o |= EXT2_MOUNT_##opt
327 #define test_opt(sb, opt)		((sb)->u.ext2_sb.s_mount_opt & \
328 					 EXT2_MOUNT_##opt)
329 /*
330  * Maximal mount counts between two filesystem checks
331  */
332 #define EXT2_DFL_MAX_MNT_COUNT		20	/* Allow 20 mounts */
333 #define EXT2_DFL_CHECKINTERVAL		0	/* Don't use interval check */
334 
335 /*
336  * Behaviour when detecting errors
337  */
338 #define EXT2_ERRORS_CONTINUE		1	/* Continue execution */
339 #define EXT2_ERRORS_RO			2	/* Remount fs read-only */
340 #define EXT2_ERRORS_PANIC		3	/* Panic */
341 #define EXT2_ERRORS_DEFAULT		EXT2_ERRORS_CONTINUE
342 
343 /*
344  * Structure of the super block
345  */
346 struct ext2_super_block {
347     __u32	s_inodes_count;		/* Inodes count */
348     __u32	s_blocks_count;		/* Blocks count */
349     __u32	s_r_blocks_count;	/* Reserved blocks count */
350     __u32	s_free_blocks_count;	/* Free blocks count */
351     __u32	s_free_inodes_count;	/* Free inodes count */
352     __u32	s_first_data_block;	/* First Data Block */
353     __u32	s_log_block_size;	/* Block size */
354     __s32	s_log_frag_size;	/* Fragment size */
355     __u32	s_blocks_per_group;	/* # Blocks per group */
356     __u32	s_frags_per_group;	/* # Fragments per group */
357     __u32	s_inodes_per_group;	/* # Inodes per group */
358     __u32	s_mtime;		/* Mount time */
359     __u32	s_wtime;		/* Write time */
360     __u16	s_mnt_count;		/* Mount count */
361     __s16	s_max_mnt_count;	/* Maximal mount count */
362     __u16	s_magic;		/* Magic signature */
363     __u16	s_state;		/* File system state */
364     __u16	s_errors;		/* Behaviour when detecting errors */
365     __u16	s_minor_rev_level; 	/* minor revision level */
366     __u32	s_lastcheck;		/* time of last check */
367     __u32	s_checkinterval;	/* max. time between checks */
368     __u32	s_creator_os;		/* OS */
369     __u32	s_rev_level;		/* Revision level */
370     __u16	s_def_resuid;		/* Default uid for reserved blocks */
371     __u16	s_def_resgid;		/* Default gid for reserved blocks */
372     /*
373      * These fields are for EXT2_DYNAMIC_REV superblocks only.
374      *
375      * Note: the difference between the compatible feature set and
376      * the incompatible feature set is that if there is a bit set
377      * in the incompatible feature set that the kernel doesn't
378      * know about, it should refuse to mount the filesystem.
379      *
380      * e2fsck's requirements are more strict; if it doesn't know
381      * about a feature in either the compatible or incompatible
382      * feature set, it must abort and not try to meddle with
383      * things it doesn't understand...
384      */
385     __u32	s_first_ino; 		/* First non-reserved inode */
386     __u16   s_inode_size; 		/* size of inode structure */
387     __u16	s_block_group_nr; 	/* block group # of this superblock */
388     __u32	s_feature_compat; 	/* compatible feature set */
389     __u32	s_feature_incompat; 	/* incompatible feature set */
390     __u32	s_feature_ro_compat; 	/* readonly-compatible feature set */
391     __u8	s_uuid[16];		/* 128-bit uuid for volume */
392     char	s_volume_name[16]; 	/* volume name */
393     char	s_last_mounted[64]; 	/* directory where last mounted */
394     __u32	s_algorithm_usage_bitmap; /* For compression */
395     /*
396      * Performance hints.  Directory preallocation should only
397      * happen if the EXT2_COMPAT_PREALLOC flag is on.
398      */
399     __u8	s_prealloc_blocks;	/* Nr of blocks to try to preallocate*/
400     __u8	s_prealloc_dir_blocks;	/* Nr to preallocate for dirs */
401     __u16	s_padding1;
402     __u32	s_reserved[204];	/* Padding to the end of the block */
403 };
404 
405 #ifdef __KERNEL__
406 #define EXT2_SB(sb)	(&((sb)->u.ext2_sb))
407 #else
408 /* Assume that user mode programs are passing in an ext2fs superblock, not
409  * a kernel struct super_block.  This will allow us to call the feature-test
410  * macros from user land. */
411 #define EXT2_SB(sb)	(sb)
412 #endif
413 
414 /*
415  * Codes for operating systems
416  */
417 #define EXT2_OS_LINUX		0
418 #define EXT2_OS_HURD		1
419 #define EXT2_OS_MASIX		2
420 #define EXT2_OS_FREEBSD		3
421 #define EXT2_OS_LITES		4
422 
423 /*
424  * Revision levels
425  */
426 #define EXT2_GOOD_OLD_REV	0	/* The good old (original) format */
427 #define EXT2_DYNAMIC_REV	1 	/* V2 format w/ dynamic inode sizes */
428 
429 #define EXT2_CURRENT_REV	EXT2_GOOD_OLD_REV
430 #define EXT2_MAX_SUPP_REV	EXT2_DYNAMIC_REV
431 
432 #define EXT2_GOOD_OLD_INODE_SIZE 128
433 
434 /*
435  * Feature set definitions
436  */
437 
438 #define EXT2_HAS_COMPAT_FEATURE(sb,mask)			\
439 	( EXT2_SB(sb)->s_es->s_feature_compat & cpu_to_le32(mask) )
440 #define EXT2_HAS_RO_COMPAT_FEATURE(sb,mask)			\
441 	( EXT2_SB(sb)->s_es->s_feature_ro_compat & cpu_to_le32(mask) )
442 #define EXT2_HAS_INCOMPAT_FEATURE(sb,mask)			\
443 	( EXT2_SB(sb)->s_es->s_feature_incompat & cpu_to_le32(mask) )
444 #define EXT2_SET_COMPAT_FEATURE(sb,mask)			\
445 	EXT2_SB(sb)->s_es->s_feature_compat |= cpu_to_le32(mask)
446 #define EXT2_SET_RO_COMPAT_FEATURE(sb,mask)			\
447 	EXT2_SB(sb)->s_es->s_feature_ro_compat |= cpu_to_le32(mask)
448 #define EXT2_SET_INCOMPAT_FEATURE(sb,mask)			\
449 	EXT2_SB(sb)->s_es->s_feature_incompat |= cpu_to_le32(mask)
450 #define EXT2_CLEAR_COMPAT_FEATURE(sb,mask)			\
451 	EXT2_SB(sb)->s_es->s_feature_compat &= ~cpu_to_le32(mask)
452 #define EXT2_CLEAR_RO_COMPAT_FEATURE(sb,mask)			\
453 	EXT2_SB(sb)->s_es->s_feature_ro_compat &= ~cpu_to_le32(mask)
454 #define EXT2_CLEAR_INCOMPAT_FEATURE(sb,mask)			\
455 	EXT2_SB(sb)->s_es->s_feature_incompat &= ~cpu_to_le32(mask)
456 
457 #define EXT2_FEATURE_COMPAT_DIR_PREALLOC	0x0001
458 #define EXT2_FEATURE_COMPAT_IMAGIC_INODES	0x0002
459 #define EXT3_FEATURE_COMPAT_HAS_JOURNAL		0x0004
460 #define EXT2_FEATURE_COMPAT_EXT_ATTR		0x0008
461 #define EXT2_FEATURE_COMPAT_RESIZE_INO		0x0010
462 #define EXT2_FEATURE_COMPAT_DIR_INDEX		0x0020
463 #define EXT2_FEATURE_COMPAT_ANY			0xffffffff
464 
465 #define EXT2_FEATURE_RO_COMPAT_SPARSE_SUPER	0x0001
466 #define EXT2_FEATURE_RO_COMPAT_LARGE_FILE	0x0002
467 #define EXT2_FEATURE_RO_COMPAT_BTREE_DIR	0x0004
468 #define EXT2_FEATURE_RO_COMPAT_ANY		0xffffffff
469 
470 #define EXT2_FEATURE_INCOMPAT_COMPRESSION	0x0001
471 #define EXT2_FEATURE_INCOMPAT_FILETYPE		0x0002
472 
473 #define EXT2_FEATURE_COMPAT_SUPP	0
474 #define EXT2_FEATURE_INCOMPAT_SUPP	EXT2_FEATURE_INCOMPAT_FILETYPE
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  * Structure of a directory entry
489  */
490 #define EXT2_NAME_LEN 255
491 
492 struct ext2_dir_entry {
493     __u32	inode;			/* Inode number */
494     __u16	rec_len;		/* Directory entry length */
495     __u16	name_len;		/* Name length */
496     char	name[EXT2_NAME_LEN];	/* File name */
497 };
498 
499 /*
500  * The new version of the directory entry.  Since EXT2 structures are
501  * stored in intel byte order, and the name_len field could never be
502  * bigger than 255 chars, it's safe to reclaim the extra byte for the
503  * file_type field.
504  */
505 struct ext2_dir_entry_2 {
506     __u32	inode;			/* Inode number */
507     __u16	rec_len;		/* Directory entry length */
508     __u8	name_len;		/* Name length */
509     __u8	file_type;
510     char	name[EXT2_NAME_LEN];	/* File name */
511 };
512 
513 /*
514  * Ext2 directory file types.  Only the low 3 bits are used.  The
515  * other bits are reserved for now.
516  */
517 enum {
518     EXT2_FT_UNKNOWN,
519     EXT2_FT_REG_FILE,
520     EXT2_FT_DIR,
521     EXT2_FT_CHRDEV,
522     EXT2_FT_BLKDEV,
523     EXT2_FT_FIFO,
524     EXT2_FT_SOCK,
525     EXT2_FT_SYMLINK,
526     EXT2_FT_MAX
527 };
528 
529 /*
530  * EXT2_DIR_PAD defines the directory entries boundaries
531  *
532  * NOTE: It must be a multiple of 4
533  */
534 #define EXT2_DIR_PAD		 	4
535 #define EXT2_DIR_ROUND 			(EXT2_DIR_PAD - 1)
536 #define EXT2_DIR_REC_LEN(name_len)	(((name_len) + 8 + EXT2_DIR_ROUND) & \
537 					 ~EXT2_DIR_ROUND)
538 
539 #ifdef __KERNEL__
540 /*
541  * Function prototypes
542  */
543 
544 /*
545  * Ok, these declarations are also in <linux/kernel.h> but none of the
546  * ext2 source programs needs to include it so they are duplicated here.
547  */
548 # define NORET_TYPE    /**/
549 # define ATTRIB_NORET  __attribute__((noreturn))
550 # define NORET_AND     noreturn,
551 
552 /* balloc.c */
553 extern int ext2_bg_has_super(struct super_block *sb, int group);
554 extern unsigned long ext2_bg_num_gdb(struct super_block *sb, int group);
555 extern int ext2_new_block (struct inode *, unsigned long,
556                                __u32 *, __u32 *, int *);
557 extern void ext2_free_blocks (struct inode *, unsigned long,
558                                   unsigned long);
559 extern unsigned long ext2_count_free_blocks (struct super_block *);
560 extern void ext2_check_blocks_bitmap (struct super_block *);
561 extern struct ext2_group_desc * ext2_get_group_desc(struct super_block * sb,
562                         unsigned int block_group,
563                         struct buffer_head ** bh);
564 
565 /* dir.c */
566 extern int ext2_add_link (struct dentry *, struct inode *);
567 extern ino_t ext2_inode_by_name(struct inode *, struct dentry *);
568 extern int ext2_make_empty(struct inode *, struct inode *);
569 extern struct ext2_dir_entry_2 * ext2_find_entry (struct inode *,struct dentry *, struct page **);
570 extern int ext2_delete_entry (struct ext2_dir_entry_2 *, struct page *);
571 extern int ext2_empty_dir (struct inode *);
572 extern struct ext2_dir_entry_2 * ext2_dotdot (struct inode *, struct page **);
573 extern void ext2_set_link(struct inode *, struct ext2_dir_entry_2 *, struct page *, struct inode *);
574 
575 /* fsync.c */
576 extern int ext2_sync_file (struct file *, struct dentry *, int);
577 extern int ext2_fsync_inode (struct inode *, int);
578 
579 /* ialloc.c */
580 extern struct inode * ext2_new_inode (const struct inode *, int);
581 extern void ext2_free_inode (struct inode *);
582 extern unsigned long ext2_count_free_inodes (struct super_block *);
583 extern void ext2_check_inodes_bitmap (struct super_block *);
584 extern unsigned long ext2_count_free (struct buffer_head *, unsigned);
585 
586 /* inode.c */
587 extern void ext2_read_inode (struct inode *);
588 extern void ext2_write_inode (struct inode *, int);
589 extern void ext2_put_inode (struct inode *);
590 extern void ext2_delete_inode (struct inode *);
591 extern int ext2_sync_inode (struct inode *);
592 extern void ext2_discard_prealloc (struct inode *);
593 extern void ext2_truncate (struct inode *);
594 
595 /* ioctl.c */
596 extern int ext2_ioctl (struct inode *, struct file *, unsigned int,
597                            unsigned long);
598 
599 /* super.c */
600 extern void ext2_error (struct super_block *, const char *, const char *, ...)
601     __attribute__ ((format (printf, 3, 4)));
602 extern NORET_TYPE void ext2_panic (struct super_block *, const char *,
603                                        const char *, ...)
604     __attribute__ ((NORET_AND format (printf, 3, 4)));
605 extern void ext2_warning (struct super_block *, const char *, const char *, ...)
606     __attribute__ ((format (printf, 3, 4)));
607 extern void ext2_update_dynamic_rev (struct super_block *sb);
608 extern void ext2_put_super (struct super_block *);
609 extern void ext2_write_super (struct super_block *);
610 extern int ext2_remount (struct super_block *, int *, char *);
611 extern struct super_block * ext2_read_super (struct super_block *,void *,int);
612 #ifndef __REACTOS__
613 extern int ext2_statfs (struct super_block *, struct statfs *);
614 #endif
615 
616 /*
617  * Inodes and files operations
618  */
619 
620 /* dir.c */
621 extern struct file_operations ext2_dir_operations;
622 
623 /* file.c */
624 extern struct inode_operations ext2_file_inode_operations;
625 extern struct file_operations ext2_file_operations;
626 
627 /* inode.c */
628 extern struct address_space_operations ext2_aops;
629 
630 /* namei.c */
631 extern struct inode_operations ext2_dir_inode_operations;
632 
633 /* symlink.c */
634 extern struct inode_operations ext2_fast_symlink_inode_operations;
635 
636 #endif	/* __KERNEL__ */
637 
638 #endif	/* _LINUX_EXT2_FS_H */
639