xref: /linux-6.15/include/linux/ext2_fs.h (revision eb2bce7f)
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_PREALLOCATE to preallocate data blocks for expanding files
33  */
34 #define EXT2_PREALLOCATE
35 #define EXT2_DEFAULT_PREALLOC_BLOCKS	8
36 
37 /*
38  * The second extended file system version
39  */
40 #define EXT2FS_DATE		"95/08/09"
41 #define EXT2FS_VERSION		"0.5b"
42 
43 /*
44  * Debug code
45  */
46 #ifdef EXT2FS_DEBUG
47 #	define ext2_debug(f, a...)	{ \
48 					printk ("EXT2-fs DEBUG (%s, %d): %s:", \
49 						__FILE__, __LINE__, __FUNCTION__); \
50 				  	printk (f, ## a); \
51 					}
52 #else
53 #	define ext2_debug(f, a...)	/**/
54 #endif
55 
56 /*
57  * Special inode numbers
58  */
59 #define	EXT2_BAD_INO		 1	/* Bad blocks inode */
60 #define EXT2_ROOT_INO		 2	/* Root inode */
61 #define EXT2_BOOT_LOADER_INO	 5	/* Boot loader inode */
62 #define EXT2_UNDEL_DIR_INO	 6	/* Undelete directory inode */
63 
64 /* First non-reserved inode for old ext2 filesystems */
65 #define EXT2_GOOD_OLD_FIRST_INO	11
66 
67 #ifdef __KERNEL__
68 #include <linux/ext2_fs_sb.h>
69 static inline struct ext2_sb_info *EXT2_SB(struct super_block *sb)
70 {
71 	return sb->s_fs_info;
72 }
73 #else
74 /* Assume that user mode programs are passing in an ext2fs superblock, not
75  * a kernel struct super_block.  This will allow us to call the feature-test
76  * macros from user land. */
77 #define EXT2_SB(sb)	(sb)
78 #endif
79 
80 /*
81  * Maximal count of links to a file
82  */
83 #define EXT2_LINK_MAX		32000
84 
85 /*
86  * Macro-instructions used to manage several block sizes
87  */
88 #define EXT2_MIN_BLOCK_SIZE		1024
89 #define	EXT2_MAX_BLOCK_SIZE		4096
90 #define EXT2_MIN_BLOCK_LOG_SIZE		  10
91 #ifdef __KERNEL__
92 # define EXT2_BLOCK_SIZE(s)		((s)->s_blocksize)
93 #else
94 # define EXT2_BLOCK_SIZE(s)		(EXT2_MIN_BLOCK_SIZE << (s)->s_log_block_size)
95 #endif
96 #define	EXT2_ADDR_PER_BLOCK(s)		(EXT2_BLOCK_SIZE(s) / sizeof (__u32))
97 #ifdef __KERNEL__
98 # define EXT2_BLOCK_SIZE_BITS(s)	((s)->s_blocksize_bits)
99 #else
100 # define EXT2_BLOCK_SIZE_BITS(s)	((s)->s_log_block_size + 10)
101 #endif
102 #ifdef __KERNEL__
103 #define	EXT2_ADDR_PER_BLOCK_BITS(s)	(EXT2_SB(s)->s_addr_per_block_bits)
104 #define EXT2_INODE_SIZE(s)		(EXT2_SB(s)->s_inode_size)
105 #define EXT2_FIRST_INO(s)		(EXT2_SB(s)->s_first_ino)
106 #else
107 #define EXT2_INODE_SIZE(s)	(((s)->s_rev_level == EXT2_GOOD_OLD_REV) ? \
108 				 EXT2_GOOD_OLD_INODE_SIZE : \
109 				 (s)->s_inode_size)
110 #define EXT2_FIRST_INO(s)	(((s)->s_rev_level == EXT2_GOOD_OLD_REV) ? \
111 				 EXT2_GOOD_OLD_FIRST_INO : \
112 				 (s)->s_first_ino)
113 #endif
114 
115 /*
116  * Macro-instructions used to manage fragments
117  */
118 #define EXT2_MIN_FRAG_SIZE		1024
119 #define	EXT2_MAX_FRAG_SIZE		4096
120 #define EXT2_MIN_FRAG_LOG_SIZE		  10
121 #ifdef __KERNEL__
122 # define EXT2_FRAG_SIZE(s)		(EXT2_SB(s)->s_frag_size)
123 # define EXT2_FRAGS_PER_BLOCK(s)	(EXT2_SB(s)->s_frags_per_block)
124 #else
125 # define EXT2_FRAG_SIZE(s)		(EXT2_MIN_FRAG_SIZE << (s)->s_log_frag_size)
126 # define EXT2_FRAGS_PER_BLOCK(s)	(EXT2_BLOCK_SIZE(s) / EXT2_FRAG_SIZE(s))
127 #endif
128 
129 /*
130  * Structure of a blocks group descriptor
131  */
132 struct ext2_group_desc
133 {
134 	__le32	bg_block_bitmap;		/* Blocks bitmap block */
135 	__le32	bg_inode_bitmap;		/* Inodes bitmap block */
136 	__le32	bg_inode_table;		/* Inodes table block */
137 	__le16	bg_free_blocks_count;	/* Free blocks count */
138 	__le16	bg_free_inodes_count;	/* Free inodes count */
139 	__le16	bg_used_dirs_count;	/* Directories count */
140 	__le16	bg_pad;
141 	__le32	bg_reserved[3];
142 };
143 
144 /*
145  * Macro-instructions used to manage group descriptors
146  */
147 #ifdef __KERNEL__
148 # define EXT2_BLOCKS_PER_GROUP(s)	(EXT2_SB(s)->s_blocks_per_group)
149 # define EXT2_DESC_PER_BLOCK(s)		(EXT2_SB(s)->s_desc_per_block)
150 # define EXT2_INODES_PER_GROUP(s)	(EXT2_SB(s)->s_inodes_per_group)
151 # define EXT2_DESC_PER_BLOCK_BITS(s)	(EXT2_SB(s)->s_desc_per_block_bits)
152 #else
153 # define EXT2_BLOCKS_PER_GROUP(s)	((s)->s_blocks_per_group)
154 # define EXT2_DESC_PER_BLOCK(s)		(EXT2_BLOCK_SIZE(s) / sizeof (struct ext2_group_desc))
155 # define EXT2_INODES_PER_GROUP(s)	((s)->s_inodes_per_group)
156 #endif
157 
158 /*
159  * Constants relative to the data blocks
160  */
161 #define	EXT2_NDIR_BLOCKS		12
162 #define	EXT2_IND_BLOCK			EXT2_NDIR_BLOCKS
163 #define	EXT2_DIND_BLOCK			(EXT2_IND_BLOCK + 1)
164 #define	EXT2_TIND_BLOCK			(EXT2_DIND_BLOCK + 1)
165 #define	EXT2_N_BLOCKS			(EXT2_TIND_BLOCK + 1)
166 
167 /*
168  * Inode flags (GETFLAGS/SETFLAGS)
169  */
170 #define	EXT2_SECRM_FL			FS_SECRM_FL	/* Secure deletion */
171 #define	EXT2_UNRM_FL			FS_UNRM_FL	/* Undelete */
172 #define	EXT2_COMPR_FL			FS_COMPR_FL	/* Compress file */
173 #define EXT2_SYNC_FL			FS_SYNC_FL	/* Synchronous updates */
174 #define EXT2_IMMUTABLE_FL		FS_IMMUTABLE_FL	/* Immutable file */
175 #define EXT2_APPEND_FL			FS_APPEND_FL	/* writes to file may only append */
176 #define EXT2_NODUMP_FL			FS_NODUMP_FL	/* do not dump file */
177 #define EXT2_NOATIME_FL			FS_NOATIME_FL	/* do not update atime */
178 /* Reserved for compression usage... */
179 #define EXT2_DIRTY_FL			FS_DIRTY_FL
180 #define EXT2_COMPRBLK_FL		FS_COMPRBLK_FL	/* One or more compressed clusters */
181 #define EXT2_NOCOMP_FL			FS_NOCOMP_FL	/* Don't compress */
182 #define EXT2_ECOMPR_FL			FS_ECOMPR_FL	/* Compression error */
183 /* End compression flags --- maybe not all used */
184 #define EXT2_BTREE_FL			FS_BTREE_FL	/* btree format dir */
185 #define EXT2_INDEX_FL			FS_INDEX_FL	/* hash-indexed directory */
186 #define EXT2_IMAGIC_FL			FS_IMAGIC_FL	/* AFS directory */
187 #define EXT2_JOURNAL_DATA_FL		FS_JOURNAL_DATA_FL /* Reserved for ext3 */
188 #define EXT2_NOTAIL_FL			FS_NOTAIL_FL	/* file tail should not be merged */
189 #define EXT2_DIRSYNC_FL			FS_DIRSYNC_FL	/* dirsync behaviour (directories only) */
190 #define EXT2_TOPDIR_FL			FS_TOPDIR_FL	/* Top of directory hierarchies*/
191 #define EXT2_RESERVED_FL		FS_RESERVED_FL	/* reserved for ext2 lib */
192 
193 #define EXT2_FL_USER_VISIBLE		FS_FL_USER_VISIBLE	/* User visible flags */
194 #define EXT2_FL_USER_MODIFIABLE		FS_FL_USER_MODIFIABLE	/* User modifiable flags */
195 
196 /*
197  * ioctl commands
198  */
199 #define	EXT2_IOC_GETFLAGS		FS_IOC_GETFLAGS
200 #define	EXT2_IOC_SETFLAGS		FS_IOC_SETFLAGS
201 #define	EXT2_IOC_GETVERSION		FS_IOC_GETVERSION
202 #define	EXT2_IOC_SETVERSION		FS_IOC_SETVERSION
203 
204 /*
205  * ioctl commands in 32 bit emulation
206  */
207 #define EXT2_IOC32_GETFLAGS		FS_IOC32_GETFLAGS
208 #define EXT2_IOC32_SETFLAGS		FS_IOC32_SETFLAGS
209 #define EXT2_IOC32_GETVERSION		FS_IOC32_GETVERSION
210 #define EXT2_IOC32_SETVERSION		FS_IOC32_SETVERSION
211 
212 /*
213  * Structure of an inode on the disk
214  */
215 struct ext2_inode {
216 	__le16	i_mode;		/* File mode */
217 	__le16	i_uid;		/* Low 16 bits of Owner Uid */
218 	__le32	i_size;		/* Size in bytes */
219 	__le32	i_atime;	/* Access time */
220 	__le32	i_ctime;	/* Creation time */
221 	__le32	i_mtime;	/* Modification time */
222 	__le32	i_dtime;	/* Deletion Time */
223 	__le16	i_gid;		/* Low 16 bits of Group Id */
224 	__le16	i_links_count;	/* Links count */
225 	__le32	i_blocks;	/* Blocks count */
226 	__le32	i_flags;	/* File flags */
227 	union {
228 		struct {
229 			__le32  l_i_reserved1;
230 		} linux1;
231 		struct {
232 			__le32  h_i_translator;
233 		} hurd1;
234 		struct {
235 			__le32  m_i_reserved1;
236 		} masix1;
237 	} osd1;				/* OS dependent 1 */
238 	__le32	i_block[EXT2_N_BLOCKS];/* Pointers to blocks */
239 	__le32	i_generation;	/* File version (for NFS) */
240 	__le32	i_file_acl;	/* File ACL */
241 	__le32	i_dir_acl;	/* Directory ACL */
242 	__le32	i_faddr;	/* Fragment address */
243 	union {
244 		struct {
245 			__u8	l_i_frag;	/* Fragment number */
246 			__u8	l_i_fsize;	/* Fragment size */
247 			__u16	i_pad1;
248 			__le16	l_i_uid_high;	/* these 2 fields    */
249 			__le16	l_i_gid_high;	/* were reserved2[0] */
250 			__u32	l_i_reserved2;
251 		} linux2;
252 		struct {
253 			__u8	h_i_frag;	/* Fragment number */
254 			__u8	h_i_fsize;	/* Fragment size */
255 			__le16	h_i_mode_high;
256 			__le16	h_i_uid_high;
257 			__le16	h_i_gid_high;
258 			__le32	h_i_author;
259 		} hurd2;
260 		struct {
261 			__u8	m_i_frag;	/* Fragment number */
262 			__u8	m_i_fsize;	/* Fragment size */
263 			__u16	m_pad1;
264 			__u32	m_i_reserved2[2];
265 		} masix2;
266 	} osd2;				/* OS dependent 2 */
267 };
268 
269 #define i_size_high	i_dir_acl
270 
271 #if defined(__KERNEL__) || defined(__linux__)
272 #define i_reserved1	osd1.linux1.l_i_reserved1
273 #define i_frag		osd2.linux2.l_i_frag
274 #define i_fsize		osd2.linux2.l_i_fsize
275 #define i_uid_low	i_uid
276 #define i_gid_low	i_gid
277 #define i_uid_high	osd2.linux2.l_i_uid_high
278 #define i_gid_high	osd2.linux2.l_i_gid_high
279 #define i_reserved2	osd2.linux2.l_i_reserved2
280 #endif
281 
282 #ifdef	__hurd__
283 #define i_translator	osd1.hurd1.h_i_translator
284 #define i_frag		osd2.hurd2.h_i_frag;
285 #define i_fsize		osd2.hurd2.h_i_fsize;
286 #define i_uid_high	osd2.hurd2.h_i_uid_high
287 #define i_gid_high	osd2.hurd2.h_i_gid_high
288 #define i_author	osd2.hurd2.h_i_author
289 #endif
290 
291 #ifdef	__masix__
292 #define i_reserved1	osd1.masix1.m_i_reserved1
293 #define i_frag		osd2.masix2.m_i_frag
294 #define i_fsize		osd2.masix2.m_i_fsize
295 #define i_reserved2	osd2.masix2.m_i_reserved2
296 #endif
297 
298 /*
299  * File system states
300  */
301 #define	EXT2_VALID_FS			0x0001	/* Unmounted cleanly */
302 #define	EXT2_ERROR_FS			0x0002	/* Errors detected */
303 
304 /*
305  * Mount flags
306  */
307 #define EXT2_MOUNT_CHECK		0x000001  /* Do mount-time checks */
308 #define EXT2_MOUNT_OLDALLOC		0x000002  /* Don't use the new Orlov allocator */
309 #define EXT2_MOUNT_GRPID		0x000004  /* Create files with directory's group */
310 #define EXT2_MOUNT_DEBUG		0x000008  /* Some debugging messages */
311 #define EXT2_MOUNT_ERRORS_CONT		0x000010  /* Continue on errors */
312 #define EXT2_MOUNT_ERRORS_RO		0x000020  /* Remount fs ro on errors */
313 #define EXT2_MOUNT_ERRORS_PANIC		0x000040  /* Panic on errors */
314 #define EXT2_MOUNT_MINIX_DF		0x000080  /* Mimics the Minix statfs */
315 #define EXT2_MOUNT_NOBH			0x000100  /* No buffer_heads */
316 #define EXT2_MOUNT_NO_UID32		0x000200  /* Disable 32-bit UIDs */
317 #define EXT2_MOUNT_XATTR_USER		0x004000  /* Extended user attributes */
318 #define EXT2_MOUNT_POSIX_ACL		0x008000  /* POSIX Access Control Lists */
319 #define EXT2_MOUNT_XIP			0x010000  /* Execute in place */
320 #define EXT2_MOUNT_USRQUOTA		0x020000 /* user quota */
321 #define EXT2_MOUNT_GRPQUOTA		0x040000 /* group quota */
322 
323 
324 #define clear_opt(o, opt)		o &= ~EXT2_MOUNT_##opt
325 #define set_opt(o, opt)			o |= EXT2_MOUNT_##opt
326 #define test_opt(sb, opt)		(EXT2_SB(sb)->s_mount_opt & \
327 					 EXT2_MOUNT_##opt)
328 /*
329  * Maximal mount counts between two filesystem checks
330  */
331 #define EXT2_DFL_MAX_MNT_COUNT		20	/* Allow 20 mounts */
332 #define EXT2_DFL_CHECKINTERVAL		0	/* Don't use interval check */
333 
334 /*
335  * Behaviour when detecting errors
336  */
337 #define EXT2_ERRORS_CONTINUE		1	/* Continue execution */
338 #define EXT2_ERRORS_RO			2	/* Remount fs read-only */
339 #define EXT2_ERRORS_PANIC		3	/* Panic */
340 #define EXT2_ERRORS_DEFAULT		EXT2_ERRORS_CONTINUE
341 
342 /*
343  * Structure of the super block
344  */
345 struct ext2_super_block {
346 	__le32	s_inodes_count;		/* Inodes count */
347 	__le32	s_blocks_count;		/* Blocks count */
348 	__le32	s_r_blocks_count;	/* Reserved blocks count */
349 	__le32	s_free_blocks_count;	/* Free blocks count */
350 	__le32	s_free_inodes_count;	/* Free inodes count */
351 	__le32	s_first_data_block;	/* First Data Block */
352 	__le32	s_log_block_size;	/* Block size */
353 	__le32	s_log_frag_size;	/* Fragment size */
354 	__le32	s_blocks_per_group;	/* # Blocks per group */
355 	__le32	s_frags_per_group;	/* # Fragments per group */
356 	__le32	s_inodes_per_group;	/* # Inodes per group */
357 	__le32	s_mtime;		/* Mount time */
358 	__le32	s_wtime;		/* Write time */
359 	__le16	s_mnt_count;		/* Mount count */
360 	__le16	s_max_mnt_count;	/* Maximal mount count */
361 	__le16	s_magic;		/* Magic signature */
362 	__le16	s_state;		/* File system state */
363 	__le16	s_errors;		/* Behaviour when detecting errors */
364 	__le16	s_minor_rev_level; 	/* minor revision level */
365 	__le32	s_lastcheck;		/* time of last check */
366 	__le32	s_checkinterval;	/* max. time between checks */
367 	__le32	s_creator_os;		/* OS */
368 	__le32	s_rev_level;		/* Revision level */
369 	__le16	s_def_resuid;		/* Default uid for reserved blocks */
370 	__le16	s_def_resgid;		/* Default gid for reserved blocks */
371 	/*
372 	 * These fields are for EXT2_DYNAMIC_REV superblocks only.
373 	 *
374 	 * Note: the difference between the compatible feature set and
375 	 * the incompatible feature set is that if there is a bit set
376 	 * in the incompatible feature set that the kernel doesn't
377 	 * know about, it should refuse to mount the filesystem.
378 	 *
379 	 * e2fsck's requirements are more strict; if it doesn't know
380 	 * about a feature in either the compatible or incompatible
381 	 * feature set, it must abort and not try to meddle with
382 	 * things it doesn't understand...
383 	 */
384 	__le32	s_first_ino; 		/* First non-reserved inode */
385 	__le16   s_inode_size; 		/* size of inode structure */
386 	__le16	s_block_group_nr; 	/* block group # of this superblock */
387 	__le32	s_feature_compat; 	/* compatible feature set */
388 	__le32	s_feature_incompat; 	/* incompatible feature set */
389 	__le32	s_feature_ro_compat; 	/* readonly-compatible feature set */
390 	__u8	s_uuid[16];		/* 128-bit uuid for volume */
391 	char	s_volume_name[16]; 	/* volume name */
392 	char	s_last_mounted[64]; 	/* directory where last mounted */
393 	__le32	s_algorithm_usage_bitmap; /* For compression */
394 	/*
395 	 * Performance hints.  Directory preallocation should only
396 	 * happen if the EXT2_COMPAT_PREALLOC flag is on.
397 	 */
398 	__u8	s_prealloc_blocks;	/* Nr of blocks to try to preallocate*/
399 	__u8	s_prealloc_dir_blocks;	/* Nr to preallocate for dirs */
400 	__u16	s_padding1;
401 	/*
402 	 * Journaling support valid if EXT3_FEATURE_COMPAT_HAS_JOURNAL set.
403 	 */
404 	__u8	s_journal_uuid[16];	/* uuid of journal superblock */
405 	__u32	s_journal_inum;		/* inode number of journal file */
406 	__u32	s_journal_dev;		/* device number of journal file */
407 	__u32	s_last_orphan;		/* start of list of inodes to delete */
408 	__u32	s_hash_seed[4];		/* HTREE hash seed */
409 	__u8	s_def_hash_version;	/* Default hash version to use */
410 	__u8	s_reserved_char_pad;
411 	__u16	s_reserved_word_pad;
412 	__le32	s_default_mount_opts;
413  	__le32	s_first_meta_bg; 	/* First metablock block group */
414 	__u32	s_reserved[190];	/* Padding to the end of the block */
415 };
416 
417 /*
418  * Codes for operating systems
419  */
420 #define EXT2_OS_LINUX		0
421 #define EXT2_OS_HURD		1
422 #define EXT2_OS_MASIX		2
423 #define EXT2_OS_FREEBSD		3
424 #define EXT2_OS_LITES		4
425 
426 /*
427  * Revision levels
428  */
429 #define EXT2_GOOD_OLD_REV	0	/* The good old (original) format */
430 #define EXT2_DYNAMIC_REV	1 	/* V2 format w/ dynamic inode sizes */
431 
432 #define EXT2_CURRENT_REV	EXT2_GOOD_OLD_REV
433 #define EXT2_MAX_SUPP_REV	EXT2_DYNAMIC_REV
434 
435 #define EXT2_GOOD_OLD_INODE_SIZE 128
436 
437 /*
438  * Feature set definitions
439  */
440 
441 #define EXT2_HAS_COMPAT_FEATURE(sb,mask)			\
442 	( EXT2_SB(sb)->s_es->s_feature_compat & cpu_to_le32(mask) )
443 #define EXT2_HAS_RO_COMPAT_FEATURE(sb,mask)			\
444 	( EXT2_SB(sb)->s_es->s_feature_ro_compat & cpu_to_le32(mask) )
445 #define EXT2_HAS_INCOMPAT_FEATURE(sb,mask)			\
446 	( EXT2_SB(sb)->s_es->s_feature_incompat & cpu_to_le32(mask) )
447 #define EXT2_SET_COMPAT_FEATURE(sb,mask)			\
448 	EXT2_SB(sb)->s_es->s_feature_compat |= cpu_to_le32(mask)
449 #define EXT2_SET_RO_COMPAT_FEATURE(sb,mask)			\
450 	EXT2_SB(sb)->s_es->s_feature_ro_compat |= cpu_to_le32(mask)
451 #define EXT2_SET_INCOMPAT_FEATURE(sb,mask)			\
452 	EXT2_SB(sb)->s_es->s_feature_incompat |= cpu_to_le32(mask)
453 #define EXT2_CLEAR_COMPAT_FEATURE(sb,mask)			\
454 	EXT2_SB(sb)->s_es->s_feature_compat &= ~cpu_to_le32(mask)
455 #define EXT2_CLEAR_RO_COMPAT_FEATURE(sb,mask)			\
456 	EXT2_SB(sb)->s_es->s_feature_ro_compat &= ~cpu_to_le32(mask)
457 #define EXT2_CLEAR_INCOMPAT_FEATURE(sb,mask)			\
458 	EXT2_SB(sb)->s_es->s_feature_incompat &= ~cpu_to_le32(mask)
459 
460 #define EXT2_FEATURE_COMPAT_DIR_PREALLOC	0x0001
461 #define EXT2_FEATURE_COMPAT_IMAGIC_INODES	0x0002
462 #define EXT3_FEATURE_COMPAT_HAS_JOURNAL		0x0004
463 #define EXT2_FEATURE_COMPAT_EXT_ATTR		0x0008
464 #define EXT2_FEATURE_COMPAT_RESIZE_INO		0x0010
465 #define EXT2_FEATURE_COMPAT_DIR_INDEX		0x0020
466 #define EXT2_FEATURE_COMPAT_ANY			0xffffffff
467 
468 #define EXT2_FEATURE_RO_COMPAT_SPARSE_SUPER	0x0001
469 #define EXT2_FEATURE_RO_COMPAT_LARGE_FILE	0x0002
470 #define EXT2_FEATURE_RO_COMPAT_BTREE_DIR	0x0004
471 #define EXT2_FEATURE_RO_COMPAT_ANY		0xffffffff
472 
473 #define EXT2_FEATURE_INCOMPAT_COMPRESSION	0x0001
474 #define EXT2_FEATURE_INCOMPAT_FILETYPE		0x0002
475 #define EXT3_FEATURE_INCOMPAT_RECOVER		0x0004
476 #define EXT3_FEATURE_INCOMPAT_JOURNAL_DEV	0x0008
477 #define EXT2_FEATURE_INCOMPAT_META_BG		0x0010
478 #define EXT2_FEATURE_INCOMPAT_ANY		0xffffffff
479 
480 #define EXT2_FEATURE_COMPAT_SUPP	EXT2_FEATURE_COMPAT_EXT_ATTR
481 #define EXT2_FEATURE_INCOMPAT_SUPP	(EXT2_FEATURE_INCOMPAT_FILETYPE| \
482 					 EXT2_FEATURE_INCOMPAT_META_BG)
483 #define EXT2_FEATURE_RO_COMPAT_SUPP	(EXT2_FEATURE_RO_COMPAT_SPARSE_SUPER| \
484 					 EXT2_FEATURE_RO_COMPAT_LARGE_FILE| \
485 					 EXT2_FEATURE_RO_COMPAT_BTREE_DIR)
486 #define EXT2_FEATURE_RO_COMPAT_UNSUPPORTED	~EXT2_FEATURE_RO_COMPAT_SUPP
487 #define EXT2_FEATURE_INCOMPAT_UNSUPPORTED	~EXT2_FEATURE_INCOMPAT_SUPP
488 
489 /*
490  * Default values for user and/or group using reserved blocks
491  */
492 #define	EXT2_DEF_RESUID		0
493 #define	EXT2_DEF_RESGID		0
494 
495 /*
496  * Default mount options
497  */
498 #define EXT2_DEFM_DEBUG		0x0001
499 #define EXT2_DEFM_BSDGROUPS	0x0002
500 #define EXT2_DEFM_XATTR_USER	0x0004
501 #define EXT2_DEFM_ACL		0x0008
502 #define EXT2_DEFM_UID16		0x0010
503     /* Not used by ext2, but reserved for use by ext3 */
504 #define EXT3_DEFM_JMODE		0x0060
505 #define EXT3_DEFM_JMODE_DATA	0x0020
506 #define EXT3_DEFM_JMODE_ORDERED	0x0040
507 #define EXT3_DEFM_JMODE_WBACK	0x0060
508 
509 /*
510  * Structure of a directory entry
511  */
512 #define EXT2_NAME_LEN 255
513 
514 struct ext2_dir_entry {
515 	__le32	inode;			/* Inode number */
516 	__le16	rec_len;		/* Directory entry length */
517 	__le16	name_len;		/* Name length */
518 	char	name[EXT2_NAME_LEN];	/* File name */
519 };
520 
521 /*
522  * The new version of the directory entry.  Since EXT2 structures are
523  * stored in intel byte order, and the name_len field could never be
524  * bigger than 255 chars, it's safe to reclaim the extra byte for the
525  * file_type field.
526  */
527 struct ext2_dir_entry_2 {
528 	__le32	inode;			/* Inode number */
529 	__le16	rec_len;		/* Directory entry length */
530 	__u8	name_len;		/* Name length */
531 	__u8	file_type;
532 	char	name[EXT2_NAME_LEN];	/* File name */
533 };
534 
535 /*
536  * Ext2 directory file types.  Only the low 3 bits are used.  The
537  * other bits are reserved for now.
538  */
539 enum {
540 	EXT2_FT_UNKNOWN,
541 	EXT2_FT_REG_FILE,
542 	EXT2_FT_DIR,
543 	EXT2_FT_CHRDEV,
544 	EXT2_FT_BLKDEV,
545 	EXT2_FT_FIFO,
546 	EXT2_FT_SOCK,
547 	EXT2_FT_SYMLINK,
548 	EXT2_FT_MAX
549 };
550 
551 /*
552  * EXT2_DIR_PAD defines the directory entries boundaries
553  *
554  * NOTE: It must be a multiple of 4
555  */
556 #define EXT2_DIR_PAD		 	4
557 #define EXT2_DIR_ROUND 			(EXT2_DIR_PAD - 1)
558 #define EXT2_DIR_REC_LEN(name_len)	(((name_len) + 8 + EXT2_DIR_ROUND) & \
559 					 ~EXT2_DIR_ROUND)
560 
561 #endif	/* _LINUX_EXT2_FS_H */
562