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 #include <linux/magic.h>
21 #include <linux/fs.h>
22 
23 /*
24  * The second extended filesystem constants/structures
25  */
26 
27 /*
28  * Define EXT2FS_DEBUG to produce debug messages
29  */
30 #undef EXT2FS_DEBUG
31 
32 /*
33  * Define EXT2_RESERVATION to reserve data blocks for expanding files
34  */
35 #define EXT2_DEFAULT_RESERVE_BLOCKS     8
36 /*max window size: 1024(direct blocks) + 3([t,d]indirect blocks) */
37 #define EXT2_MAX_RESERVE_BLOCKS         1027
38 #define EXT2_RESERVE_WINDOW_NOT_ALLOCATED 0
39 /*
40  * The second extended file system version
41  */
42 #define EXT2FS_DATE		"95/08/09"
43 #define EXT2FS_VERSION		"0.5b"
44 
45 /*
46  * Debug code
47  */
48 #ifdef EXT2FS_DEBUG
49 #	define ext2_debug(f, a...)	{ \
50 					printk ("EXT2-fs DEBUG (%s, %d): %s:", \
51 						__FILE__, __LINE__, __func__); \
52 				  	printk (f, ## a); \
53 					}
54 #else
55 #	define ext2_debug(f, a...)	/**/
56 #endif
57 
58 /*
59  * Special inode numbers
60  */
61 #define	EXT2_BAD_INO		 1	/* Bad blocks inode */
62 #define EXT2_ROOT_INO		 2	/* Root inode */
63 #define EXT2_BOOT_LOADER_INO	 5	/* Boot loader inode */
64 #define EXT2_UNDEL_DIR_INO	 6	/* Undelete directory inode */
65 
66 /* First non-reserved inode for old ext2 filesystems */
67 #define EXT2_GOOD_OLD_FIRST_INO	11
68 
69 #ifdef __KERNEL__
70 #include <linux/ext2_fs_sb.h>
EXT2_SB(struct super_block * sb)71 static inline struct ext2_sb_info *EXT2_SB(struct super_block *sb)
72 {
73 	return sb->s_fs_info;
74 }
75 #else
76 /* Assume that user mode programs are passing in an ext2fs superblock, not
77  * a kernel struct super_block.  This will allow us to call the feature-test
78  * macros from user land. */
79 #define EXT2_SB(sb)	(sb)
80 #endif
81 
82 /*
83  * Maximal count of links to a file
84  */
85 #define EXT2_LINK_MAX		32000
86 
87 /*
88  * Macro-instructions used to manage several block sizes
89  */
90 #define EXT2_MIN_BLOCK_SIZE		1024
91 #define	EXT2_MAX_BLOCK_SIZE		4096
92 #define EXT2_MIN_BLOCK_LOG_SIZE		  10
93 #ifdef __KERNEL__
94 # define EXT2_BLOCK_SIZE(s)		((s)->s_blocksize)
95 #else
96 # define EXT2_BLOCK_SIZE(s)		(EXT2_MIN_BLOCK_SIZE << (s)->s_log_block_size)
97 #endif
98 #define	EXT2_ADDR_PER_BLOCK(s)		(EXT2_BLOCK_SIZE(s) / sizeof (__u32))
99 #ifdef __KERNEL__
100 # define EXT2_BLOCK_SIZE_BITS(s)	((s)->s_blocksize_bits)
101 #else
102 # define EXT2_BLOCK_SIZE_BITS(s)	((s)->s_log_block_size + 10)
103 #endif
104 #ifdef __KERNEL__
105 #define	EXT2_ADDR_PER_BLOCK_BITS(s)	(EXT2_SB(s)->s_addr_per_block_bits)
106 #define EXT2_INODE_SIZE(s)		(EXT2_SB(s)->s_inode_size)
107 #define EXT2_FIRST_INO(s)		(EXT2_SB(s)->s_first_ino)
108 #else
109 #define EXT2_INODE_SIZE(s)	(((s)->s_rev_level == EXT2_GOOD_OLD_REV) ? \
110 				 EXT2_GOOD_OLD_INODE_SIZE : \
111 				 (s)->s_inode_size)
112 #define EXT2_FIRST_INO(s)	(((s)->s_rev_level == EXT2_GOOD_OLD_REV) ? \
113 				 EXT2_GOOD_OLD_FIRST_INO : \
114 				 (s)->s_first_ino)
115 #endif
116 
117 /*
118  * Macro-instructions used to manage fragments
119  */
120 #define EXT2_MIN_FRAG_SIZE		1024
121 #define	EXT2_MAX_FRAG_SIZE		4096
122 #define EXT2_MIN_FRAG_LOG_SIZE		  10
123 #ifdef __KERNEL__
124 # define EXT2_FRAG_SIZE(s)		(EXT2_SB(s)->s_frag_size)
125 # define EXT2_FRAGS_PER_BLOCK(s)	(EXT2_SB(s)->s_frags_per_block)
126 #else
127 # define EXT2_FRAG_SIZE(s)		(EXT2_MIN_FRAG_SIZE << (s)->s_log_frag_size)
128 # define EXT2_FRAGS_PER_BLOCK(s)	(EXT2_BLOCK_SIZE(s) / EXT2_FRAG_SIZE(s))
129 #endif
130 
131 /*
132  * Structure of a blocks group descriptor
133  */
134 struct ext2_group_desc
135 {
136 	__le32	bg_block_bitmap;		/* Blocks bitmap block */
137 	__le32	bg_inode_bitmap;		/* Inodes bitmap block */
138 	__le32	bg_inode_table;		/* Inodes table block */
139 	__le16	bg_free_blocks_count;	/* Free blocks count */
140 	__le16	bg_free_inodes_count;	/* Free inodes count */
141 	__le16	bg_used_dirs_count;	/* Directories count */
142 	__le16	bg_pad;
143 	__le32	bg_reserved[3];
144 };
145 
146 /*
147  * Macro-instructions used to manage group descriptors
148  */
149 #ifdef __KERNEL__
150 # define EXT2_BLOCKS_PER_GROUP(s)	(EXT2_SB(s)->s_blocks_per_group)
151 # define EXT2_DESC_PER_BLOCK(s)		(EXT2_SB(s)->s_desc_per_block)
152 # define EXT2_INODES_PER_GROUP(s)	(EXT2_SB(s)->s_inodes_per_group)
153 # define EXT2_DESC_PER_BLOCK_BITS(s)	(EXT2_SB(s)->s_desc_per_block_bits)
154 #else
155 # define EXT2_BLOCKS_PER_GROUP(s)	((s)->s_blocks_per_group)
156 # define EXT2_DESC_PER_BLOCK(s)		(EXT2_BLOCK_SIZE(s) / sizeof (struct ext2_group_desc))
157 # define EXT2_INODES_PER_GROUP(s)	((s)->s_inodes_per_group)
158 #endif
159 
160 /*
161  * Constants relative to the data blocks
162  */
163 #define	EXT2_NDIR_BLOCKS		12
164 #define	EXT2_IND_BLOCK			EXT2_NDIR_BLOCKS
165 #define	EXT2_DIND_BLOCK			(EXT2_IND_BLOCK + 1)
166 #define	EXT2_TIND_BLOCK			(EXT2_DIND_BLOCK + 1)
167 #define	EXT2_N_BLOCKS			(EXT2_TIND_BLOCK + 1)
168 
169 /*
170  * Inode flags (GETFLAGS/SETFLAGS)
171  */
172 #define	EXT2_SECRM_FL			FS_SECRM_FL	/* Secure deletion */
173 #define	EXT2_UNRM_FL			FS_UNRM_FL	/* Undelete */
174 #define	EXT2_COMPR_FL			FS_COMPR_FL	/* Compress file */
175 #define EXT2_SYNC_FL			FS_SYNC_FL	/* Synchronous updates */
176 #define EXT2_IMMUTABLE_FL		FS_IMMUTABLE_FL	/* Immutable file */
177 #define EXT2_APPEND_FL			FS_APPEND_FL	/* writes to file may only append */
178 #define EXT2_NODUMP_FL			FS_NODUMP_FL	/* do not dump file */
179 #define EXT2_NOATIME_FL			FS_NOATIME_FL	/* do not update atime */
180 /* Reserved for compression usage... */
181 #define EXT2_DIRTY_FL			FS_DIRTY_FL
182 #define EXT2_COMPRBLK_FL		FS_COMPRBLK_FL	/* One or more compressed clusters */
183 #define EXT2_NOCOMP_FL			FS_NOCOMP_FL	/* Don't compress */
184 #define EXT2_ECOMPR_FL			FS_ECOMPR_FL	/* Compression error */
185 /* End compression flags --- maybe not all used */
186 #define EXT2_BTREE_FL			FS_BTREE_FL	/* btree format dir */
187 #define EXT2_INDEX_FL			FS_INDEX_FL	/* hash-indexed directory */
188 #define EXT2_IMAGIC_FL			FS_IMAGIC_FL	/* AFS directory */
189 #define EXT2_JOURNAL_DATA_FL		FS_JOURNAL_DATA_FL /* Reserved for ext3 */
190 #define EXT2_NOTAIL_FL			FS_NOTAIL_FL	/* file tail should not be merged */
191 #define EXT2_DIRSYNC_FL			FS_DIRSYNC_FL	/* dirsync behaviour (directories only) */
192 #define EXT2_TOPDIR_FL			FS_TOPDIR_FL	/* Top of directory hierarchies*/
193 #define EXT2_RESERVED_FL		FS_RESERVED_FL	/* reserved for ext2 lib */
194 
195 #define EXT2_FL_USER_VISIBLE		FS_FL_USER_VISIBLE	/* User visible flags */
196 #define EXT2_FL_USER_MODIFIABLE		FS_FL_USER_MODIFIABLE	/* User modifiable flags */
197 
198 /* Flags that should be inherited by new inodes from their parent. */
199 #define EXT2_FL_INHERITED (EXT2_SECRM_FL | EXT2_UNRM_FL | EXT2_COMPR_FL |\
200 			   EXT2_SYNC_FL | EXT2_NODUMP_FL |\
201 			   EXT2_NOATIME_FL | EXT2_COMPRBLK_FL |\
202 			   EXT2_NOCOMP_FL | EXT2_JOURNAL_DATA_FL |\
203 			   EXT2_NOTAIL_FL | EXT2_DIRSYNC_FL)
204 
205 /* Flags that are appropriate for regular files (all but dir-specific ones). */
206 #define EXT2_REG_FLMASK (~(EXT2_DIRSYNC_FL | EXT2_TOPDIR_FL))
207 
208 /* Flags that are appropriate for non-directories/regular files. */
209 #define EXT2_OTHER_FLMASK (EXT2_NODUMP_FL | EXT2_NOATIME_FL)
210 
211 /* Mask out flags that are inappropriate for the given type of inode. */
ext2_mask_flags(umode_t mode,__u32 flags)212 static inline __u32 ext2_mask_flags(umode_t mode, __u32 flags)
213 {
214 	if (S_ISDIR(mode))
215 		return flags;
216 	else if (S_ISREG(mode))
217 		return flags & EXT2_REG_FLMASK;
218 	else
219 		return flags & EXT2_OTHER_FLMASK;
220 }
221 
222 /*
223  * ioctl commands
224  */
225 #define	EXT2_IOC_GETFLAGS		FS_IOC_GETFLAGS
226 #define	EXT2_IOC_SETFLAGS		FS_IOC_SETFLAGS
227 #define	EXT2_IOC_GETVERSION		FS_IOC_GETVERSION
228 #define	EXT2_IOC_SETVERSION		FS_IOC_SETVERSION
229 #define	EXT2_IOC_GETRSVSZ		_IOR('f', 5, long)
230 #define	EXT2_IOC_SETRSVSZ		_IOW('f', 6, long)
231 
232 /*
233  * ioctl commands in 32 bit emulation
234  */
235 #define EXT2_IOC32_GETFLAGS		FS_IOC32_GETFLAGS
236 #define EXT2_IOC32_SETFLAGS		FS_IOC32_SETFLAGS
237 #define EXT2_IOC32_GETVERSION		FS_IOC32_GETVERSION
238 #define EXT2_IOC32_SETVERSION		FS_IOC32_SETVERSION
239 
240 /*
241  * Structure of an inode on the disk
242  */
243 struct ext2_inode {
244 	__le16	i_mode;		/* File mode */
245 	__le16	i_uid;		/* Low 16 bits of Owner Uid */
246 	__le32	i_size;		/* Size in bytes */
247 	__le32	i_atime;	/* Access time */
248 	__le32	i_ctime;	/* Creation time */
249 	__le32	i_mtime;	/* Modification time */
250 	__le32	i_dtime;	/* Deletion Time */
251 	__le16	i_gid;		/* Low 16 bits of Group Id */
252 	__le16	i_links_count;	/* Links count */
253 	__le32	i_blocks;	/* Blocks count */
254 	__le32	i_flags;	/* File flags */
255 	union {
256 		struct {
257 			__le32  l_i_reserved1;
258 		} linux1;
259 		struct {
260 			__le32  h_i_translator;
261 		} hurd1;
262 		struct {
263 			__le32  m_i_reserved1;
264 		} masix1;
265 	} osd1;				/* OS dependent 1 */
266 	__le32	i_block[EXT2_N_BLOCKS];/* Pointers to blocks */
267 	__le32	i_generation;	/* File version (for NFS) */
268 	__le32	i_file_acl;	/* File ACL */
269 	__le32	i_dir_acl;	/* Directory ACL */
270 	__le32	i_faddr;	/* Fragment address */
271 	union {
272 		struct {
273 			__u8	l_i_frag;	/* Fragment number */
274 			__u8	l_i_fsize;	/* Fragment size */
275 			__u16	i_pad1;
276 			__le16	l_i_uid_high;	/* these 2 fields    */
277 			__le16	l_i_gid_high;	/* were reserved2[0] */
278 			__u32	l_i_reserved2;
279 		} linux2;
280 		struct {
281 			__u8	h_i_frag;	/* Fragment number */
282 			__u8	h_i_fsize;	/* Fragment size */
283 			__le16	h_i_mode_high;
284 			__le16	h_i_uid_high;
285 			__le16	h_i_gid_high;
286 			__le32	h_i_author;
287 		} hurd2;
288 		struct {
289 			__u8	m_i_frag;	/* Fragment number */
290 			__u8	m_i_fsize;	/* Fragment size */
291 			__u16	m_pad1;
292 			__u32	m_i_reserved2[2];
293 		} masix2;
294 	} osd2;				/* OS dependent 2 */
295 };
296 
297 #define i_size_high	i_dir_acl
298 
299 #if defined(__KERNEL__) || defined(__linux__)
300 #define i_reserved1	osd1.linux1.l_i_reserved1
301 #define i_frag		osd2.linux2.l_i_frag
302 #define i_fsize		osd2.linux2.l_i_fsize
303 #define i_uid_low	i_uid
304 #define i_gid_low	i_gid
305 #define i_uid_high	osd2.linux2.l_i_uid_high
306 #define i_gid_high	osd2.linux2.l_i_gid_high
307 #define i_reserved2	osd2.linux2.l_i_reserved2
308 #endif
309 
310 #ifdef	__hurd__
311 #define i_translator	osd1.hurd1.h_i_translator
312 #define i_frag		osd2.hurd2.h_i_frag
313 #define i_fsize		osd2.hurd2.h_i_fsize
314 #define i_uid_high	osd2.hurd2.h_i_uid_high
315 #define i_gid_high	osd2.hurd2.h_i_gid_high
316 #define i_author	osd2.hurd2.h_i_author
317 #endif
318 
319 #ifdef	__masix__
320 #define i_reserved1	osd1.masix1.m_i_reserved1
321 #define i_frag		osd2.masix2.m_i_frag
322 #define i_fsize		osd2.masix2.m_i_fsize
323 #define i_reserved2	osd2.masix2.m_i_reserved2
324 #endif
325 
326 /*
327  * File system states
328  */
329 #define	EXT2_VALID_FS			0x0001	/* Unmounted cleanly */
330 #define	EXT2_ERROR_FS			0x0002	/* Errors detected */
331 
332 /*
333  * Mount flags
334  */
335 #define EXT2_MOUNT_CHECK		0x000001  /* Do mount-time checks */
336 #define EXT2_MOUNT_OLDALLOC		0x000002  /* Don't use the new Orlov allocator */
337 #define EXT2_MOUNT_GRPID		0x000004  /* Create files with directory's group */
338 #define EXT2_MOUNT_DEBUG		0x000008  /* Some debugging messages */
339 #define EXT2_MOUNT_ERRORS_CONT		0x000010  /* Continue on errors */
340 #define EXT2_MOUNT_ERRORS_RO		0x000020  /* Remount fs ro on errors */
341 #define EXT2_MOUNT_ERRORS_PANIC		0x000040  /* Panic on errors */
342 #define EXT2_MOUNT_MINIX_DF		0x000080  /* Mimics the Minix statfs */
343 #define EXT2_MOUNT_NOBH			0x000100  /* No buffer_heads */
344 #define EXT2_MOUNT_NO_UID32		0x000200  /* Disable 32-bit UIDs */
345 #define EXT2_MOUNT_XATTR_USER		0x004000  /* Extended user attributes */
346 #define EXT2_MOUNT_POSIX_ACL		0x008000  /* POSIX Access Control Lists */
347 #define EXT2_MOUNT_XIP			0x010000  /* Execute in place */
348 #define EXT2_MOUNT_USRQUOTA		0x020000  /* user quota */
349 #define EXT2_MOUNT_GRPQUOTA		0x040000  /* group quota */
350 #define EXT2_MOUNT_RESERVATION		0x080000  /* Preallocation */
351 
352 
353 #define clear_opt(o, opt)		o &= ~EXT2_MOUNT_##opt
354 #define set_opt(o, opt)			o |= EXT2_MOUNT_##opt
355 #define test_opt(sb, opt)		(EXT2_SB(sb)->s_mount_opt & \
356 					 EXT2_MOUNT_##opt)
357 /*
358  * Maximal mount counts between two filesystem checks
359  */
360 #define EXT2_DFL_MAX_MNT_COUNT		20	/* Allow 20 mounts */
361 #define EXT2_DFL_CHECKINTERVAL		0	/* Don't use interval check */
362 
363 /*
364  * Behaviour when detecting errors
365  */
366 #define EXT2_ERRORS_CONTINUE		1	/* Continue execution */
367 #define EXT2_ERRORS_RO			2	/* Remount fs read-only */
368 #define EXT2_ERRORS_PANIC		3	/* Panic */
369 #define EXT2_ERRORS_DEFAULT		EXT2_ERRORS_CONTINUE
370 
371 /*
372  * Structure of the super block
373  */
374 struct ext2_super_block {
375 	__le32	s_inodes_count;		/* Inodes count */
376 	__le32	s_blocks_count;		/* Blocks count */
377 	__le32	s_r_blocks_count;	/* Reserved blocks count */
378 	__le32	s_free_blocks_count;	/* Free blocks count */
379 	__le32	s_free_inodes_count;	/* Free inodes count */
380 	__le32	s_first_data_block;	/* First Data Block */
381 	__le32	s_log_block_size;	/* Block size */
382 	__le32	s_log_frag_size;	/* Fragment size */
383 	__le32	s_blocks_per_group;	/* # Blocks per group */
384 	__le32	s_frags_per_group;	/* # Fragments per group */
385 	__le32	s_inodes_per_group;	/* # Inodes per group */
386 	__le32	s_mtime;		/* Mount time */
387 	__le32	s_wtime;		/* Write time */
388 	__le16	s_mnt_count;		/* Mount count */
389 	__le16	s_max_mnt_count;	/* Maximal mount count */
390 	__le16	s_magic;		/* Magic signature */
391 	__le16	s_state;		/* File system state */
392 	__le16	s_errors;		/* Behaviour when detecting errors */
393 	__le16	s_minor_rev_level; 	/* minor revision level */
394 	__le32	s_lastcheck;		/* time of last check */
395 	__le32	s_checkinterval;	/* max. time between checks */
396 	__le32	s_creator_os;		/* OS */
397 	__le32	s_rev_level;		/* Revision level */
398 	__le16	s_def_resuid;		/* Default uid for reserved blocks */
399 	__le16	s_def_resgid;		/* Default gid for reserved blocks */
400 	/*
401 	 * These fields are for EXT2_DYNAMIC_REV superblocks only.
402 	 *
403 	 * Note: the difference between the compatible feature set and
404 	 * the incompatible feature set is that if there is a bit set
405 	 * in the incompatible feature set that the kernel doesn't
406 	 * know about, it should refuse to mount the filesystem.
407 	 *
408 	 * e2fsck's requirements are more strict; if it doesn't know
409 	 * about a feature in either the compatible or incompatible
410 	 * feature set, it must abort and not try to meddle with
411 	 * things it doesn't understand...
412 	 */
413 	__le32	s_first_ino; 		/* First non-reserved inode */
414 	__le16   s_inode_size; 		/* size of inode structure */
415 	__le16	s_block_group_nr; 	/* block group # of this superblock */
416 	__le32	s_feature_compat; 	/* compatible feature set */
417 	__le32	s_feature_incompat; 	/* incompatible feature set */
418 	__le32	s_feature_ro_compat; 	/* readonly-compatible feature set */
419 	__u8	s_uuid[16];		/* 128-bit uuid for volume */
420 	char	s_volume_name[16]; 	/* volume name */
421 	char	s_last_mounted[64]; 	/* directory where last mounted */
422 	__le32	s_algorithm_usage_bitmap; /* For compression */
423 	/*
424 	 * Performance hints.  Directory preallocation should only
425 	 * happen if the EXT2_COMPAT_PREALLOC flag is on.
426 	 */
427 	__u8	s_prealloc_blocks;	/* Nr of blocks to try to preallocate*/
428 	__u8	s_prealloc_dir_blocks;	/* Nr to preallocate for dirs */
429 	__u16	s_padding1;
430 	/*
431 	 * Journaling support valid if EXT3_FEATURE_COMPAT_HAS_JOURNAL set.
432 	 */
433 	__u8	s_journal_uuid[16];	/* uuid of journal superblock */
434 	__u32	s_journal_inum;		/* inode number of journal file */
435 	__u32	s_journal_dev;		/* device number of journal file */
436 	__u32	s_last_orphan;		/* start of list of inodes to delete */
437 	__u32	s_hash_seed[4];		/* HTREE hash seed */
438 	__u8	s_def_hash_version;	/* Default hash version to use */
439 	__u8	s_reserved_char_pad;
440 	__u16	s_reserved_word_pad;
441 	__le32	s_default_mount_opts;
442  	__le32	s_first_meta_bg; 	/* First metablock block group */
443 	__u32	s_reserved[190];	/* Padding to the end of the block */
444 };
445 
446 /*
447  * Codes for operating systems
448  */
449 #define EXT2_OS_LINUX		0
450 #define EXT2_OS_HURD		1
451 #define EXT2_OS_MASIX		2
452 #define EXT2_OS_FREEBSD		3
453 #define EXT2_OS_LITES		4
454 
455 /*
456  * Revision levels
457  */
458 #define EXT2_GOOD_OLD_REV	0	/* The good old (original) format */
459 #define EXT2_DYNAMIC_REV	1 	/* V2 format w/ dynamic inode sizes */
460 
461 #define EXT2_CURRENT_REV	EXT2_GOOD_OLD_REV
462 #define EXT2_MAX_SUPP_REV	EXT2_DYNAMIC_REV
463 
464 #define EXT2_GOOD_OLD_INODE_SIZE 128
465 
466 /*
467  * Feature set definitions
468  */
469 
470 #define EXT2_HAS_COMPAT_FEATURE(sb,mask)			\
471 	( EXT2_SB(sb)->s_es->s_feature_compat & cpu_to_le32(mask) )
472 #define EXT2_HAS_RO_COMPAT_FEATURE(sb,mask)			\
473 	( EXT2_SB(sb)->s_es->s_feature_ro_compat & cpu_to_le32(mask) )
474 #define EXT2_HAS_INCOMPAT_FEATURE(sb,mask)			\
475 	( EXT2_SB(sb)->s_es->s_feature_incompat & cpu_to_le32(mask) )
476 #define EXT2_SET_COMPAT_FEATURE(sb,mask)			\
477 	EXT2_SB(sb)->s_es->s_feature_compat |= cpu_to_le32(mask)
478 #define EXT2_SET_RO_COMPAT_FEATURE(sb,mask)			\
479 	EXT2_SB(sb)->s_es->s_feature_ro_compat |= cpu_to_le32(mask)
480 #define EXT2_SET_INCOMPAT_FEATURE(sb,mask)			\
481 	EXT2_SB(sb)->s_es->s_feature_incompat |= cpu_to_le32(mask)
482 #define EXT2_CLEAR_COMPAT_FEATURE(sb,mask)			\
483 	EXT2_SB(sb)->s_es->s_feature_compat &= ~cpu_to_le32(mask)
484 #define EXT2_CLEAR_RO_COMPAT_FEATURE(sb,mask)			\
485 	EXT2_SB(sb)->s_es->s_feature_ro_compat &= ~cpu_to_le32(mask)
486 #define EXT2_CLEAR_INCOMPAT_FEATURE(sb,mask)			\
487 	EXT2_SB(sb)->s_es->s_feature_incompat &= ~cpu_to_le32(mask)
488 
489 #define EXT2_FEATURE_COMPAT_DIR_PREALLOC	0x0001
490 #define EXT2_FEATURE_COMPAT_IMAGIC_INODES	0x0002
491 #define EXT3_FEATURE_COMPAT_HAS_JOURNAL		0x0004
492 #define EXT2_FEATURE_COMPAT_EXT_ATTR		0x0008
493 #define EXT2_FEATURE_COMPAT_RESIZE_INO		0x0010
494 #define EXT2_FEATURE_COMPAT_DIR_INDEX		0x0020
495 #define EXT2_FEATURE_COMPAT_ANY			0xffffffff
496 
497 #define EXT2_FEATURE_RO_COMPAT_SPARSE_SUPER	0x0001
498 #define EXT2_FEATURE_RO_COMPAT_LARGE_FILE	0x0002
499 #define EXT2_FEATURE_RO_COMPAT_BTREE_DIR	0x0004
500 #define EXT2_FEATURE_RO_COMPAT_ANY		0xffffffff
501 
502 #define EXT2_FEATURE_INCOMPAT_COMPRESSION	0x0001
503 #define EXT2_FEATURE_INCOMPAT_FILETYPE		0x0002
504 #define EXT3_FEATURE_INCOMPAT_RECOVER		0x0004
505 #define EXT3_FEATURE_INCOMPAT_JOURNAL_DEV	0x0008
506 #define EXT2_FEATURE_INCOMPAT_META_BG		0x0010
507 #define EXT2_FEATURE_INCOMPAT_ANY		0xffffffff
508 
509 #define EXT2_FEATURE_COMPAT_SUPP	EXT2_FEATURE_COMPAT_EXT_ATTR
510 #define EXT2_FEATURE_INCOMPAT_SUPP	(EXT2_FEATURE_INCOMPAT_FILETYPE| \
511 					 EXT2_FEATURE_INCOMPAT_META_BG)
512 #define EXT2_FEATURE_RO_COMPAT_SUPP	(EXT2_FEATURE_RO_COMPAT_SPARSE_SUPER| \
513 					 EXT2_FEATURE_RO_COMPAT_LARGE_FILE| \
514 					 EXT2_FEATURE_RO_COMPAT_BTREE_DIR)
515 #define EXT2_FEATURE_RO_COMPAT_UNSUPPORTED	~EXT2_FEATURE_RO_COMPAT_SUPP
516 #define EXT2_FEATURE_INCOMPAT_UNSUPPORTED	~EXT2_FEATURE_INCOMPAT_SUPP
517 
518 /*
519  * Default values for user and/or group using reserved blocks
520  */
521 #define	EXT2_DEF_RESUID		0
522 #define	EXT2_DEF_RESGID		0
523 
524 /*
525  * Default mount options
526  */
527 #define EXT2_DEFM_DEBUG		0x0001
528 #define EXT2_DEFM_BSDGROUPS	0x0002
529 #define EXT2_DEFM_XATTR_USER	0x0004
530 #define EXT2_DEFM_ACL		0x0008
531 #define EXT2_DEFM_UID16		0x0010
532     /* Not used by ext2, but reserved for use by ext3 */
533 #define EXT3_DEFM_JMODE		0x0060
534 #define EXT3_DEFM_JMODE_DATA	0x0020
535 #define EXT3_DEFM_JMODE_ORDERED	0x0040
536 #define EXT3_DEFM_JMODE_WBACK	0x0060
537 
538 /*
539  * Structure of a directory entry
540  */
541 #define EXT2_NAME_LEN 255
542 
543 struct ext2_dir_entry {
544 	__le32	inode;			/* Inode number */
545 	__le16	rec_len;		/* Directory entry length */
546 	__le16	name_len;		/* Name length */
547 	char	name[EXT2_NAME_LEN];	/* File name */
548 };
549 
550 /*
551  * The new version of the directory entry.  Since EXT2 structures are
552  * stored in intel byte order, and the name_len field could never be
553  * bigger than 255 chars, it's safe to reclaim the extra byte for the
554  * file_type field.
555  */
556 struct ext2_dir_entry_2 {
557 	__le32	inode;			/* Inode number */
558 	__le16	rec_len;		/* Directory entry length */
559 	__u8	name_len;		/* Name length */
560 	__u8	file_type;
561 	char	name[EXT2_NAME_LEN];	/* File name */
562 };
563 
564 /*
565  * Ext2 directory file types.  Only the low 3 bits are used.  The
566  * other bits are reserved for now.
567  */
568 enum {
569 	EXT2_FT_UNKNOWN		= 0,
570 	EXT2_FT_REG_FILE	= 1,
571 	EXT2_FT_DIR		= 2,
572 	EXT2_FT_CHRDEV		= 3,
573 	EXT2_FT_BLKDEV		= 4,
574 	EXT2_FT_FIFO		= 5,
575 	EXT2_FT_SOCK		= 6,
576 	EXT2_FT_SYMLINK		= 7,
577 	EXT2_FT_MAX
578 };
579 
580 /*
581  * EXT2_DIR_PAD defines the directory entries boundaries
582  *
583  * NOTE: It must be a multiple of 4
584  */
585 #define EXT2_DIR_PAD		 	4
586 #define EXT2_DIR_ROUND 			(EXT2_DIR_PAD - 1)
587 #define EXT2_DIR_REC_LEN(name_len)	(((name_len) + 8 + EXT2_DIR_ROUND) & \
588 					 ~EXT2_DIR_ROUND)
589 #define EXT2_MAX_REC_LEN		((1<<16)-1)
590 
591 #endif	/* _LINUX_EXT2_FS_H */
592