xref: /linux-6.15/include/linux/ext2_fs.h (revision a686cd89)
1 /*
2  *  linux/include/linux/ext2_fs.h
3  *
4  * Copyright (C) 1992, 1993, 1994, 1995
5  * Remy Card ([email protected])
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 
565 static inline ext2_fsblk_t
566 ext2_group_first_block_no(struct super_block *sb, unsigned long group_no)
567 {
568 	return group_no * (ext2_fsblk_t)EXT2_BLOCKS_PER_GROUP(sb) +
569 		le32_to_cpu(EXT2_SB(sb)->s_es->s_first_data_block);
570 }
571 
572 #endif	/* _LINUX_EXT2_FS_H */
573