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 inode numbers
44  */
45 #define EXT2_BAD_INO		 1	/* Bad blocks inode */
46 #define EXT2_ROOT_INO		 2	/* Root inode */
47 #define EXT4_USR_QUOTA_INO	 3	/* User quota inode */
48 #define EXT4_GRP_QUOTA_INO	 4	/* Group quota 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 #define EXT2_EXCLUDE_INO	 9	/* The "exclude" inode, for snapshots */
54 #define EXT4_REPLICA_INO	10	/* Used by non-upstream feature */
55 
56 /* First non-reserved inode for old ext2 filesystems */
57 #define EXT2_GOOD_OLD_FIRST_INO	11
58 
59 /*
60  * The second extended file system magic number
61  */
62 #define EXT2_SUPER_MAGIC	0xEF53
63 
64 #ifdef __KERNEL__
65 #define EXT2_SB(sb)	(&((sb)->u.ext2_sb))
66 #else
67 /* Assume that user mode programs are passing in an ext2fs superblock, not
68  * a kernel struct super_block.  This will allow us to call the feature-test
69  * macros from user land. */
70 #define EXT2_SB(sb)	(sb)
71 #endif
72 
73 /*
74  * Maximal count of links to a file
75  */
76 #define EXT2_LINK_MAX		65000
77 
78 /*
79  * Macro-instructions used to manage several block sizes
80  */
81 #define EXT2_MIN_BLOCK_LOG_SIZE		10	/* 1024 */
82 #define EXT2_MAX_BLOCK_LOG_SIZE		16	/* 65536 */
83 #define EXT2_MIN_BLOCK_SIZE	(1 << EXT2_MIN_BLOCK_LOG_SIZE)
84 #define EXT2_MAX_BLOCK_SIZE	(1 << EXT2_MAX_BLOCK_LOG_SIZE)
85 #ifdef __KERNEL__
86 #define EXT2_BLOCK_SIZE(s)	((s)->s_blocksize)
87 #define EXT2_BLOCK_SIZE_BITS(s)	((s)->s_blocksize_bits)
88 #define EXT2_ADDR_PER_BLOCK_BITS(s)	(EXT2_SB(s)->addr_per_block_bits)
89 #define EXT2_INODE_SIZE(s)	(EXT2_SB(s)->s_inode_size)
90 #define EXT2_FIRST_INO(s)	(EXT2_SB(s)->s_first_ino)
91 #else
92 #define EXT2_BLOCK_SIZE(s)	(EXT2_MIN_BLOCK_SIZE << (s)->s_log_block_size)
93 #define EXT2_BLOCK_SIZE_BITS(s)	((s)->s_log_block_size + 10)
94 #define EXT2_INODE_SIZE(s)	(((s)->s_rev_level == EXT2_GOOD_OLD_REV) ? \
95 				 EXT2_GOOD_OLD_INODE_SIZE : (s)->s_inode_size)
96 #define EXT2_FIRST_INO(s)	(((s)->s_rev_level == EXT2_GOOD_OLD_REV) ? \
97 				 EXT2_GOOD_OLD_FIRST_INO : (s)->s_first_ino)
98 #endif
99 #define EXT2_ADDR_PER_BLOCK(s)	(EXT2_BLOCK_SIZE(s) / sizeof(__u32))
100 
101 /*
102  * Macro-instructions used to manage allocation clusters
103  */
104 #define EXT2_MIN_CLUSTER_LOG_SIZE	EXT2_MIN_BLOCK_LOG_SIZE
105 #define EXT2_MAX_CLUSTER_LOG_SIZE	29	/* 512MB  */
106 #define EXT2_MIN_CLUSTER_SIZE		EXT2_MIN_BLOCK_SIZE
107 #define EXT2_MAX_CLUSTER_SIZE		(1 << EXT2_MAX_CLUSTER_LOG_SIZE)
108 #define EXT2_CLUSTER_SIZE(s)		(EXT2_MIN_BLOCK_SIZE << \
109 						(s)->s_log_cluster_size)
110 #define EXT2_CLUSTER_SIZE_BITS(s)	((s)->s_log_cluster_size + 10)
111 
112 /*
113  * Macro-instructions used to manage fragments
114  *
115  * Note: for backwards compatibility only, for the dump program.
116  * Ext2/3/4 will never support fragments....
117  */
118 #define EXT2_MIN_FRAG_SIZE              EXT2_MIN_BLOCK_SIZE
119 #define EXT2_MAX_FRAG_SIZE              EXT2_MAX_BLOCK_SIZE
120 #define EXT2_MIN_FRAG_LOG_SIZE          EXT2_MIN_BLOCK_LOG_SIZE
121 #define EXT2_FRAG_SIZE(s)		EXT2_BLOCK_SIZE(s)
122 #define EXT2_FRAGS_PER_BLOCK(s)		1
123 
124 /*
125  * ACL structures
126  */
127 struct ext2_acl_header	/* Header of Access Control Lists */
128 {
129 	__u32	aclh_size;
130 	__u32	aclh_file_count;
131 	__u32	aclh_acle_count;
132 	__u32	aclh_first_acle;
133 };
134 
135 struct ext2_acl_entry	/* Access Control List Entry */
136 {
137 	__u32	acle_size;
138 	__u16	acle_perms;	/* Access permissions */
139 	__u16	acle_type;	/* Type of entry */
140 	__u16	acle_tag;	/* User or group identity */
141 	__u16	acle_pad1;
142 	__u32	acle_next;	/* Pointer on next entry for the */
143 					/* same inode or on next free entry */
144 };
145 
146 /*
147  * Structure of a blocks group descriptor
148  */
149 struct ext2_group_desc
150 {
151 	__u32	bg_block_bitmap;	/* Blocks bitmap block */
152 	__u32	bg_inode_bitmap;	/* Inodes bitmap block */
153 	__u32	bg_inode_table;		/* Inodes table block */
154 	__u16	bg_free_blocks_count;	/* Free blocks count */
155 	__u16	bg_free_inodes_count;	/* Free inodes count */
156 	__u16	bg_used_dirs_count;	/* Directories count */
157 	__u16	bg_flags;
158 	__u32	bg_exclude_bitmap_lo;	/* Exclude bitmap for snapshots */
159 	__u16	bg_block_bitmap_csum_lo;/* crc32c(s_uuid+grp_num+bitmap) LSB */
160 	__u16	bg_inode_bitmap_csum_lo;/* crc32c(s_uuid+grp_num+bitmap) LSB */
161 	__u16	bg_itable_unused;	/* Unused inodes count */
162 	__u16	bg_checksum;		/* crc16(s_uuid+group_num+group_desc)*/
163 };
164 
165 /*
166  * Structure of a blocks group descriptor
167  */
168 struct ext4_group_desc
169 {
170 	__u32	bg_block_bitmap;	/* Blocks bitmap block */
171 	__u32	bg_inode_bitmap;	/* Inodes bitmap block */
172 	__u32	bg_inode_table;		/* Inodes table block */
173 	__u16	bg_free_blocks_count;	/* Free blocks count */
174 	__u16	bg_free_inodes_count;	/* Free inodes count */
175 	__u16	bg_used_dirs_count;	/* Directories count */
176 	__u16	bg_flags;		/* EXT4_BG_flags (INODE_UNINIT, etc) */
177 	__u32	bg_exclude_bitmap_lo;	/* Exclude bitmap for snapshots */
178 	__u16	bg_block_bitmap_csum_lo;/* crc32c(s_uuid+grp_num+bitmap) LSB */
179 	__u16	bg_inode_bitmap_csum_lo;/* crc32c(s_uuid+grp_num+bitmap) LSB */
180 	__u16	bg_itable_unused;	/* Unused inodes count */
181 	__u16	bg_checksum;		/* crc16(sb_uuid+group+desc) */
182 	__u32	bg_block_bitmap_hi;	/* Blocks bitmap block MSB */
183 	__u32	bg_inode_bitmap_hi;	/* Inodes bitmap block MSB */
184 	__u32	bg_inode_table_hi;	/* Inodes table block MSB */
185 	__u16	bg_free_blocks_count_hi;/* Free blocks count MSB */
186 	__u16	bg_free_inodes_count_hi;/* Free inodes count MSB */
187 	__u16	bg_used_dirs_count_hi;	/* Directories count MSB */
188 	__u16	bg_itable_unused_hi;	/* Unused inodes count MSB */
189 	__u32	bg_exclude_bitmap_hi;	/* Exclude bitmap block MSB */
190 	__u16	bg_block_bitmap_csum_hi;/* crc32c(s_uuid+grp_num+bitmap) MSB */
191 	__u16	bg_inode_bitmap_csum_hi;/* crc32c(s_uuid+grp_num+bitmap) MSB */
192 	__u32	bg_reserved;
193 };
194 
195 #define EXT2_BG_INODE_UNINIT	0x0001 /* Inode table/bitmap not initialized */
196 #define EXT2_BG_BLOCK_UNINIT	0x0002 /* Block bitmap not initialized */
197 #define EXT2_BG_INODE_ZEROED	0x0004 /* On-disk itable initialized to zero */
198 
199 /*
200  * Data structures used by the directory indexing feature
201  *
202  * Note: all of the multibyte integer fields are little endian.
203  */
204 
205 /*
206  * Note: dx_root_info is laid out so that if it should somehow get
207  * overlaid by a dirent the two low bits of the hash version will be
208  * zero.  Therefore, the hash version mod 4 should never be 0.
209  * Sincerely, the paranoia department.
210  */
211 struct ext2_dx_root_info {
212 	__u32 reserved_zero;
213 	__u8 hash_version; /* 0 now, 1 at release */
214 	__u8 info_length; /* 8 */
215 	__u8 indirect_levels;
216 	__u8 unused_flags;
217 };
218 
219 #define EXT2_HASH_LEGACY		0
220 #define EXT2_HASH_HALF_MD4		1
221 #define EXT2_HASH_TEA			2
222 #define EXT2_HASH_LEGACY_UNSIGNED	3 /* reserved for userspace lib */
223 #define EXT2_HASH_HALF_MD4_UNSIGNED	4 /* reserved for userspace lib */
224 #define EXT2_HASH_TEA_UNSIGNED		5 /* reserved for userspace lib */
225 
226 #define EXT2_HASH_FLAG_INCOMPAT	0x1
227 
228 struct ext2_dx_entry {
229 	__u32 hash;
230 	__u32 block;
231 };
232 
233 struct ext2_dx_countlimit {
234 	__u16 limit;
235 	__u16 count;
236 };
237 
238 
239 /*
240  * Macro-instructions used to manage group descriptors
241  */
242 #define EXT2_MIN_DESC_SIZE             32
243 #define EXT2_MIN_DESC_SIZE_64BIT       64
244 #define EXT2_MAX_DESC_SIZE             EXT2_MIN_BLOCK_SIZE
245 #define EXT2_DESC_SIZE(s)                                                \
246        ((EXT2_SB(s)->s_feature_incompat & EXT4_FEATURE_INCOMPAT_64BIT) ? \
247 	(s)->s_desc_size : EXT2_MIN_DESC_SIZE)
248 
249 #define EXT2_BLOCKS_PER_GROUP(s)	(EXT2_SB(s)->s_blocks_per_group)
250 #define EXT2_INODES_PER_GROUP(s)	(EXT2_SB(s)->s_inodes_per_group)
251 #define EXT2_CLUSTERS_PER_GROUP(s)	(EXT2_SB(s)->s_clusters_per_group)
252 #define EXT2_INODES_PER_BLOCK(s)	(EXT2_BLOCK_SIZE(s)/EXT2_INODE_SIZE(s))
253 /* limits imposed by 16-bit value gd_free_{blocks,inode}_count */
254 #define EXT2_MAX_BLOCKS_PER_GROUP(s)	((((unsigned) 1 << 16) - 8) *	\
255 					 (EXT2_CLUSTER_SIZE(s) / \
256 					  EXT2_BLOCK_SIZE(s)))
257 #define EXT2_MAX_CLUSTERS_PER_GROUP(s)	(((unsigned) 1 << 16) - 8)
258 #define EXT2_MAX_INODES_PER_GROUP(s)	(((unsigned) 1 << 16) - \
259 					 EXT2_INODES_PER_BLOCK(s))
260 #ifdef __KERNEL__
261 #define EXT2_DESC_PER_BLOCK(s)		(EXT2_SB(s)->s_desc_per_block)
262 #define EXT2_DESC_PER_BLOCK_BITS(s)	(EXT2_SB(s)->s_desc_per_block_bits)
263 #else
264 #define EXT2_DESC_PER_BLOCK(s)		(EXT2_BLOCK_SIZE(s) / EXT2_DESC_SIZE(s))
265 #endif
266 
267 /*
268  * Constants relative to the data blocks
269  */
270 #define EXT2_NDIR_BLOCKS		12
271 #define EXT2_IND_BLOCK			EXT2_NDIR_BLOCKS
272 #define EXT2_DIND_BLOCK			(EXT2_IND_BLOCK + 1)
273 #define EXT2_TIND_BLOCK			(EXT2_DIND_BLOCK + 1)
274 #define EXT2_N_BLOCKS			(EXT2_TIND_BLOCK + 1)
275 
276 /*
277  * Inode flags
278  */
279 #define EXT2_SECRM_FL			0x00000001 /* Secure deletion */
280 #define EXT2_UNRM_FL			0x00000002 /* Undelete */
281 #define EXT2_COMPR_FL			0x00000004 /* Compress file */
282 #define EXT2_SYNC_FL			0x00000008 /* Synchronous updates */
283 #define EXT2_IMMUTABLE_FL		0x00000010 /* Immutable file */
284 #define EXT2_APPEND_FL			0x00000020 /* writes to file may only append */
285 #define EXT2_NODUMP_FL			0x00000040 /* do not dump file */
286 #define EXT2_NOATIME_FL			0x00000080 /* do not update atime */
287 /* Reserved for compression usage... */
288 #define EXT2_DIRTY_FL			0x00000100
289 #define EXT2_COMPRBLK_FL		0x00000200 /* One or more compressed clusters */
290 #define EXT2_NOCOMPR_FL			0x00000400 /* Access raw compressed data */
291 #define EXT2_ECOMPR_FL			0x00000800 /* Compression error */
292 /* End compression flags --- maybe not all used */
293 #define EXT2_BTREE_FL			0x00001000 /* btree format dir */
294 #define EXT2_INDEX_FL			0x00001000 /* hash-indexed directory */
295 #define EXT2_IMAGIC_FL			0x00002000
296 #define EXT3_JOURNAL_DATA_FL		0x00004000 /* file data should be journaled */
297 #define EXT2_NOTAIL_FL			0x00008000 /* file tail should not be merged */
298 #define EXT2_DIRSYNC_FL 		0x00010000 /* Synchronous directory modifications */
299 #define EXT2_TOPDIR_FL			0x00020000 /* Top of directory hierarchies*/
300 #define EXT4_HUGE_FILE_FL               0x00040000 /* Set to each huge file */
301 #define EXT4_EXTENTS_FL 		0x00080000 /* Inode uses extents */
302 #define EXT4_EA_INODE_FL	        0x00200000 /* Inode used for large EA */
303 /* EXT4_EOFBLOCKS_FL 0x00400000 was here */
304 #define FS_NOCOW_FL			0x00800000 /* Do not cow file */
305 #define EXT4_SNAPFILE_FL		0x01000000  /* Inode is a snapshot */
306 #define EXT4_SNAPFILE_DELETED_FL	0x04000000  /* Snapshot is being deleted */
307 #define EXT4_SNAPFILE_SHRUNK_FL		0x08000000  /* Snapshot shrink has completed */
308 #define EXT2_RESERVED_FL		0x80000000 /* reserved for ext2 lib */
309 
310 #define EXT2_FL_USER_VISIBLE		0x004BDFFF /* User visible flags */
311 #define EXT2_FL_USER_MODIFIABLE		0x004B80FF /* User modifiable flags */
312 
313 /*
314  * ioctl commands
315  */
316 
317 /* Used for online resize */
318 struct ext2_new_group_input {
319 	__u32 group;		/* Group number for this data */
320 	__u32 block_bitmap;	/* Absolute block number of block bitmap */
321 	__u32 inode_bitmap;	/* Absolute block number of inode bitmap */
322 	__u32 inode_table;	/* Absolute block number of inode table start */
323 	__u32 blocks_count;	/* Total number of blocks in this group */
324 	__u16 reserved_blocks;	/* Number of reserved blocks in this group */
325 	__u16 unused;		/* Number of reserved GDT blocks in group */
326 };
327 
328 struct ext4_new_group_input {
329 	__u32 group;		/* Group number for this data */
330 	__u64 block_bitmap;	/* Absolute block number of block bitmap */
331 	__u64 inode_bitmap;	/* Absolute block number of inode bitmap */
332 	__u64 inode_table;	/* Absolute block number of inode table start */
333 	__u32 blocks_count;	/* Total number of blocks in this group */
334 	__u16 reserved_blocks;	/* Number of reserved blocks in this group */
335 	__u16 unused;
336 };
337 
338 #ifdef __GNU__			/* Needed for the Hurd */
339 #define _IOT_ext2_new_group_input _IOT (_IOTS(__u32), 5, _IOTS(__u16), 2, 0, 0)
340 #endif
341 
342 #define EXT2_IOC_GETFLAGS		_IOR('f', 1, long)
343 #define EXT2_IOC_SETFLAGS		_IOW('f', 2, long)
344 #define EXT2_IOC_GETVERSION		_IOR('v', 1, long)
345 #define EXT2_IOC_SETVERSION		_IOW('v', 2, long)
346 #define EXT2_IOC_GETVERSION_NEW		_IOR('f', 3, long)
347 #define EXT2_IOC_SETVERSION_NEW		_IOW('f', 4, long)
348 #define EXT2_IOC_GROUP_EXTEND		_IOW('f', 7, unsigned long)
349 #define EXT2_IOC_GROUP_ADD		_IOW('f', 8,struct ext2_new_group_input)
350 #define EXT4_IOC_GROUP_ADD		_IOW('f', 8,struct ext4_new_group_input)
351 #define EXT4_IOC_RESIZE_FS		_IOW('f', 16, __u64)
352 
353 /*
354  * Structure of an inode on the disk
355  */
356 struct ext2_inode {
357 	__u16	i_mode;		/* File mode */
358 	__u16	i_uid;		/* Low 16 bits of Owner Uid */
359 	__u32	i_size;		/* Size in bytes */
360 	__u32	i_atime;	/* Access time */
361 	__u32	i_ctime;	/* Inode change time */
362 	__u32	i_mtime;	/* Modification time */
363 	__u32	i_dtime;	/* Deletion Time */
364 	__u16	i_gid;		/* Low 16 bits of Group Id */
365 	__u16	i_links_count;	/* Links count */
366 	__u32	i_blocks;	/* Blocks count */
367 	__u32	i_flags;	/* File flags */
368 	union {
369 		struct {
370 			__u32	l_i_version; /* was l_i_reserved1 */
371 		} linux1;
372 		struct {
373 			__u32  h_i_translator;
374 		} hurd1;
375 	} osd1;				/* OS dependent 1 */
376 	__u32	i_block[EXT2_N_BLOCKS];/* Pointers to blocks */
377 	__u32	i_generation;	/* File version (for NFS) */
378 	__u32	i_file_acl;	/* File ACL */
379 	__u32	i_size_high;	/* Formerly i_dir_acl, directory ACL */
380 	__u32	i_faddr;	/* Fragment address */
381 	union {
382 		struct {
383 			__u16	l_i_blocks_hi;
384 			__u16	l_i_file_acl_high;
385 			__u16	l_i_uid_high;	/* these 2 fields    */
386 			__u16	l_i_gid_high;	/* were reserved2[0] */
387 			__u16	l_i_checksum_lo; /* crc32c(uuid+inum+inode) */
388 			__u16	l_i_reserved;
389 		} linux2;
390 		struct {
391 			__u8	h_i_frag;	/* Fragment number */
392 			__u8	h_i_fsize;	/* Fragment size */
393 			__u16	h_i_mode_high;
394 			__u16	h_i_uid_high;
395 			__u16	h_i_gid_high;
396 			__u32	h_i_author;
397 		} hurd2;
398 	} osd2;				/* OS dependent 2 */
399 };
400 
401 /*
402  * Permanent part of an large inode on the disk
403  */
404 struct ext2_inode_large {
405 	__u16	i_mode;		/* File mode */
406 	__u16	i_uid;		/* Low 16 bits of Owner Uid */
407 	__u32	i_size;		/* Size in bytes */
408 	__u32	i_atime;	/* Access time */
409 	__u32	i_ctime;	/* Inode Change time */
410 	__u32	i_mtime;	/* Modification time */
411 	__u32	i_dtime;	/* Deletion Time */
412 	__u16	i_gid;		/* Low 16 bits of Group Id */
413 	__u16	i_links_count;	/* Links count */
414 	__u32	i_blocks;	/* Blocks count */
415 	__u32	i_flags;	/* File flags */
416 	union {
417 		struct {
418 			__u32	l_i_version; /* was l_i_reserved1 */
419 		} linux1;
420 		struct {
421 			__u32  h_i_translator;
422 		} hurd1;
423 	} osd1;				/* OS dependent 1 */
424 	__u32	i_block[EXT2_N_BLOCKS];/* Pointers to blocks */
425 	__u32	i_generation;	/* File version (for NFS) */
426 	__u32	i_file_acl;	/* File ACL */
427 	__u32	i_size_high;	/* Formerly i_dir_acl, directory ACL */
428 	__u32	i_faddr;	/* Fragment address */
429 	union {
430 		struct {
431 			__u16	l_i_blocks_hi;
432 			__u16	l_i_file_acl_high;
433 			__u16	l_i_uid_high;	/* these 2 fields    */
434 			__u16	l_i_gid_high;	/* were reserved2[0] */
435 			__u16	l_i_checksum_lo; /* crc32c(uuid+inum+inode) */
436 			__u16	l_i_reserved;
437 		} linux2;
438 		struct {
439 			__u8	h_i_frag;	/* Fragment number */
440 			__u8	h_i_fsize;	/* Fragment size */
441 			__u16	h_i_mode_high;
442 			__u16	h_i_uid_high;
443 			__u16	h_i_gid_high;
444 			__u32	h_i_author;
445 		} hurd2;
446 	} osd2;				/* OS dependent 2 */
447 	__u16	i_extra_isize;
448 	__u16	i_checksum_hi;	/* crc32c(uuid+inum+inode) */
449 	__u32	i_ctime_extra;	/* extra Change time (nsec << 2 | epoch) */
450 	__u32	i_mtime_extra;	/* extra Modification time (nsec << 2 | epoch) */
451 	__u32	i_atime_extra;	/* extra Access time (nsec << 2 | epoch) */
452 	__u32	i_crtime;	/* File creation time */
453 	__u32	i_crtime_extra;	/* extra File creation time (nsec << 2 | epoch)*/
454 	__u32	i_version_hi;	/* high 32 bits for 64-bit version */
455 };
456 
457 #define i_dir_acl	i_size_high
458 
459 #if defined(__KERNEL__) || defined(__linux__)
460 #define i_reserved1	osd1.linux1.l_i_reserved1
461 #define i_frag		osd2.linux2.l_i_frag
462 #define i_fsize		osd2.linux2.l_i_fsize
463 #define i_uid_low	i_uid
464 #define i_gid_low	i_gid
465 #define i_uid_high	osd2.linux2.l_i_uid_high
466 #define i_gid_high	osd2.linux2.l_i_gid_high
467 #else
468 #if defined(__GNU__)
469 
470 #define i_translator	osd1.hurd1.h_i_translator
471 #define i_frag		osd2.hurd2.h_i_frag;
472 #define i_fsize		osd2.hurd2.h_i_fsize;
473 #define i_uid_high	osd2.hurd2.h_i_uid_high
474 #define i_gid_high	osd2.hurd2.h_i_gid_high
475 #define i_author	osd2.hurd2.h_i_author
476 
477 #endif  /* __GNU__ */
478 #endif	/* defined(__KERNEL__) || defined(__linux__) */
479 
480 #define inode_uid(inode)	((inode).i_uid | (inode).osd2.linux2.l_i_uid_high << 16)
481 #define inode_gid(inode)	((inode).i_gid | (inode).osd2.linux2.l_i_gid_high << 16)
482 #define ext2fs_set_i_uid_high(inode,x) ((inode).osd2.linux2.l_i_uid_high = (x))
483 #define ext2fs_set_i_gid_high(inode,x) ((inode).osd2.linux2.l_i_gid_high = (x))
484 
485 /*
486  * File system states
487  */
488 #define EXT2_VALID_FS			0x0001	/* Unmounted cleanly */
489 #define EXT2_ERROR_FS			0x0002	/* Errors detected */
490 #define EXT3_ORPHAN_FS			0x0004	/* Orphans being recovered */
491 
492 /*
493  * Misc. filesystem flags
494  */
495 #define EXT2_FLAGS_SIGNED_HASH		0x0001  /* Signed dirhash in use */
496 #define EXT2_FLAGS_UNSIGNED_HASH	0x0002  /* Unsigned dirhash in use */
497 #define EXT2_FLAGS_TEST_FILESYS		0x0004	/* OK for use on development code */
498 #define EXT2_FLAGS_IS_SNAPSHOT		0x0010	/* This is a snapshot image */
499 #define EXT2_FLAGS_FIX_SNAPSHOT		0x0020	/* Snapshot inodes corrupted */
500 #define EXT2_FLAGS_FIX_EXCLUDE		0x0040	/* Exclude bitmaps corrupted */
501 
502 /*
503  * Mount flags
504  */
505 #define EXT2_MOUNT_CHECK		0x0001	/* Do mount-time checks */
506 #define EXT2_MOUNT_GRPID		0x0004	/* Create files with directory's group */
507 #define EXT2_MOUNT_DEBUG		0x0008	/* Some debugging messages */
508 #define EXT2_MOUNT_ERRORS_CONT		0x0010	/* Continue on errors */
509 #define EXT2_MOUNT_ERRORS_RO		0x0020	/* Remount fs ro on errors */
510 #define EXT2_MOUNT_ERRORS_PANIC		0x0040	/* Panic on errors */
511 #define EXT2_MOUNT_MINIX_DF		0x0080	/* Mimics the Minix statfs */
512 #define EXT2_MOUNT_NO_UID32		0x0200  /* Disable 32-bit UIDs */
513 
514 #define clear_opt(o, opt)		o &= ~EXT2_MOUNT_##opt
515 #define set_opt(o, opt)			o |= EXT2_MOUNT_##opt
516 #define test_opt(sb, opt)		(EXT2_SB(sb)->s_mount_opt & \
517 					 EXT2_MOUNT_##opt)
518 /*
519  * Maximal mount counts between two filesystem checks
520  */
521 #define EXT2_DFL_MAX_MNT_COUNT		20	/* Allow 20 mounts */
522 #define EXT2_DFL_CHECKINTERVAL		0	/* Don't use interval check */
523 
524 /*
525  * Behaviour when detecting errors
526  */
527 #define EXT2_ERRORS_CONTINUE		1	/* Continue execution */
528 #define EXT2_ERRORS_RO			2	/* Remount fs read-only */
529 #define EXT2_ERRORS_PANIC		3	/* Panic */
530 #define EXT2_ERRORS_DEFAULT		EXT2_ERRORS_CONTINUE
531 
532 #if (__GNUC__ >= 4)
533 #define ext4_offsetof(TYPE,MEMBER) __builtin_offsetof(TYPE,MEMBER)
534 #else
535 #define ext4_offsetof(TYPE, MEMBER) ((size_t) &((TYPE *)0)->MEMBER)
536 #endif
537 
538 /*
539  * Structure of the super block
540  */
541 struct ext2_super_block {
542 	__u32	s_inodes_count;		/* Inodes count */
543 	__u32	s_blocks_count;		/* Blocks count */
544 	__u32	s_r_blocks_count;	/* Reserved blocks count */
545 	__u32	s_free_blocks_count;	/* Free blocks count */
546 	__u32	s_free_inodes_count;	/* Free inodes count */
547 	__u32	s_first_data_block;	/* First Data Block */
548 	__u32	s_log_block_size;	/* Block size */
549 	__u32	s_log_cluster_size;	/* Allocation cluster size */
550 	__u32	s_blocks_per_group;	/* # Blocks per group */
551 	__u32	s_clusters_per_group;	/* # Fragments per group */
552 	__u32	s_inodes_per_group;	/* # Inodes per group */
553 	__u32	s_mtime;		/* Mount time */
554 	__u32	s_wtime;		/* Write time */
555 	__u16	s_mnt_count;		/* Mount count */
556 	__s16	s_max_mnt_count;	/* Maximal mount count */
557 	__u16	s_magic;		/* Magic signature */
558 	__u16	s_state;		/* File system state */
559 	__u16	s_errors;		/* Behaviour when detecting errors */
560 	__u16	s_minor_rev_level;	/* minor revision level */
561 	__u32	s_lastcheck;		/* time of last check */
562 	__u32	s_checkinterval;	/* max. time between checks */
563 	__u32	s_creator_os;		/* OS */
564 	__u32	s_rev_level;		/* Revision level */
565 	__u16	s_def_resuid;		/* Default uid for reserved blocks */
566 	__u16	s_def_resgid;		/* Default gid for reserved blocks */
567 	/*
568 	 * These fields are for EXT2_DYNAMIC_REV superblocks only.
569 	 *
570 	 * Note: the difference between the compatible feature set and
571 	 * the incompatible feature set is that if there is a bit set
572 	 * in the incompatible feature set that the kernel doesn't
573 	 * know about, it should refuse to mount the filesystem.
574 	 *
575 	 * e2fsck's requirements are more strict; if it doesn't know
576 	 * about a feature in either the compatible or incompatible
577 	 * feature set, it must abort and not try to meddle with
578 	 * things it doesn't understand...
579 	 */
580 	__u32	s_first_ino;		/* First non-reserved inode */
581 	__u16   s_inode_size;		/* size of inode structure */
582 	__u16	s_block_group_nr;	/* block group # of this superblock */
583 	__u32	s_feature_compat;	/* compatible feature set */
584 	__u32	s_feature_incompat;	/* incompatible feature set */
585 	__u32	s_feature_ro_compat;	/* readonly-compatible feature set */
586 	__u8	s_uuid[16];		/* 128-bit uuid for volume */
587 	char	s_volume_name[16];	/* volume name */
588 	char	s_last_mounted[64];	/* directory where last mounted */
589 	__u32	s_algorithm_usage_bitmap; /* For compression */
590 	/*
591 	 * Performance hints.  Directory preallocation should only
592 	 * happen if the EXT2_FEATURE_COMPAT_DIR_PREALLOC flag is on.
593 	 */
594 	__u8	s_prealloc_blocks;	/* Nr of blocks to try to preallocate*/
595 	__u8	s_prealloc_dir_blocks;	/* Nr to preallocate for dirs */
596 	__u16	s_reserved_gdt_blocks;	/* Per group table for online growth */
597 	/*
598 	 * Journaling support valid if EXT2_FEATURE_COMPAT_HAS_JOURNAL set.
599 	 */
600 	__u8	s_journal_uuid[16];	/* uuid of journal superblock */
601 	__u32	s_journal_inum;		/* inode number of journal file */
602 	__u32	s_journal_dev;		/* device number of journal file */
603 	__u32	s_last_orphan;		/* start of list of inodes to delete */
604 	__u32	s_hash_seed[4];		/* HTREE hash seed */
605 	__u8	s_def_hash_version;	/* Default hash version to use */
606 	__u8	s_jnl_backup_type; 	/* Default type of journal backup */
607 	__u16	s_desc_size;		/* Group desc. size: INCOMPAT_64BIT */
608 	__u32	s_default_mount_opts;
609 	__u32	s_first_meta_bg;	/* First metablock group */
610 	__u32	s_mkfs_time;		/* When the filesystem was created */
611 	__u32	s_jnl_blocks[17]; 	/* Backup of the journal inode */
612 	__u32	s_blocks_count_hi;	/* Blocks count high 32bits */
613 	__u32	s_r_blocks_count_hi;	/* Reserved blocks count high 32 bits*/
614 	__u32	s_free_blocks_hi; 	/* Free blocks count */
615 	__u16	s_min_extra_isize;	/* All inodes have at least # bytes */
616 	__u16	s_want_extra_isize; 	/* New inodes should reserve # bytes */
617 	__u32	s_flags;		/* Miscellaneous flags */
618 	__u16   s_raid_stride;		/* RAID stride */
619 	__u16   s_mmp_update_interval;  /* # seconds to wait in MMP checking */
620 	__u64   s_mmp_block;            /* Block for multi-mount protection */
621 	__u32   s_raid_stripe_width;    /* blocks on all data disks (N*stride)*/
622 	__u8	s_log_groups_per_flex;	/* FLEX_BG group size */
623 	__u8    s_reserved_char_pad;
624 	__u16	s_reserved_pad;		/* Padding to next 32bits */
625 	__u64	s_kbytes_written;	/* nr of lifetime kilobytes written */
626 	__u32	s_snapshot_inum;	/* Inode number of active snapshot */
627 	__u32	s_snapshot_id;		/* sequential ID of active snapshot */
628 	__u64	s_snapshot_r_blocks_count; /* reserved blocks for active
629 					      snapshot's future use */
630 	__u32	s_snapshot_list;	/* inode number of the head of the on-disk snapshot list */
631 #define EXT4_S_ERR_START ext4_offsetof(struct ext2_super_block, s_error_count)
632 	__u32	s_error_count;		/* number of fs errors */
633 	__u32	s_first_error_time;	/* first time an error happened */
634 	__u32	s_first_error_ino;	/* inode involved in first error */
635 	__u64	s_first_error_block;	/* block involved of first error */
636 	__u8	s_first_error_func[32];	/* function where the error happened */
637 	__u32	s_first_error_line;	/* line number where error happened */
638 	__u32	s_last_error_time;	/* most recent time of an error */
639 	__u32	s_last_error_ino;	/* inode involved in last error */
640 	__u32	s_last_error_line;	/* line number where error happened */
641 	__u64	s_last_error_block;	/* block involved of last error */
642 	__u8	s_last_error_func[32];	/* function where the error happened */
643 #define EXT4_S_ERR_END ext4_offsetof(struct ext2_super_block, s_mount_opts)
644 	__u8	s_mount_opts[64];
645 	__u32	s_usr_quota_inum;	/* inode number of user quota file */
646 	__u32	s_grp_quota_inum;	/* inode number of group quota file */
647 	__u32	s_overhead_blocks;	/* overhead blocks/clusters in fs */
648 	__u32   s_reserved[108];        /* Padding to the end of the block */
649 	__u32	s_checksum;		/* crc32c(superblock) */
650 };
651 
652 #define EXT4_S_ERR_LEN (EXT4_S_ERR_END - EXT4_S_ERR_START)
653 
654 /*
655  * Codes for operating systems
656  */
657 #define EXT2_OS_LINUX		0
658 #define EXT2_OS_HURD		1
659 #define EXT2_OBSO_OS_MASIX	2
660 #define EXT2_OS_FREEBSD		3
661 #define EXT2_OS_LITES		4
662 
663 /*
664  * Revision levels
665  */
666 #define EXT2_GOOD_OLD_REV	0	/* The good old (original) format */
667 #define EXT2_DYNAMIC_REV	1	/* V2 format w/ dynamic inode sizes */
668 
669 #define EXT2_CURRENT_REV	EXT2_GOOD_OLD_REV
670 #define EXT2_MAX_SUPP_REV	EXT2_DYNAMIC_REV
671 
672 #define EXT2_GOOD_OLD_INODE_SIZE 128
673 
674 /*
675  * Journal inode backup types
676  */
677 #define EXT3_JNL_BACKUP_BLOCKS	1
678 
679 /*
680  * Feature set definitions
681  */
682 
683 #define EXT2_HAS_COMPAT_FEATURE(sb,mask)			\
684 	( EXT2_SB(sb)->s_feature_compat & (mask) )
685 #define EXT2_HAS_RO_COMPAT_FEATURE(sb,mask)			\
686 	( EXT2_SB(sb)->s_feature_ro_compat & (mask) )
687 #define EXT2_HAS_INCOMPAT_FEATURE(sb,mask)			\
688 	( EXT2_SB(sb)->s_feature_incompat & (mask) )
689 
690 #define EXT2_FEATURE_COMPAT_DIR_PREALLOC	0x0001
691 #define EXT2_FEATURE_COMPAT_IMAGIC_INODES	0x0002
692 #define EXT3_FEATURE_COMPAT_HAS_JOURNAL		0x0004
693 #define EXT2_FEATURE_COMPAT_EXT_ATTR		0x0008
694 #define EXT2_FEATURE_COMPAT_RESIZE_INODE	0x0010
695 #define EXT2_FEATURE_COMPAT_DIR_INDEX		0x0020
696 #define EXT2_FEATURE_COMPAT_LAZY_BG		0x0040
697 /* #define EXT2_FEATURE_COMPAT_EXCLUDE_INODE	0x0080 not used, legacy */
698 #define EXT2_FEATURE_COMPAT_EXCLUDE_BITMAP	0x0100
699 
700 
701 #define EXT2_FEATURE_RO_COMPAT_SPARSE_SUPER	0x0001
702 #define EXT2_FEATURE_RO_COMPAT_LARGE_FILE	0x0002
703 /* #define EXT2_FEATURE_RO_COMPAT_BTREE_DIR	0x0004 not used */
704 #define EXT4_FEATURE_RO_COMPAT_HUGE_FILE	0x0008
705 #define EXT4_FEATURE_RO_COMPAT_GDT_CSUM		0x0010
706 #define EXT4_FEATURE_RO_COMPAT_DIR_NLINK	0x0020
707 #define EXT4_FEATURE_RO_COMPAT_EXTRA_ISIZE	0x0040
708 #define EXT4_FEATURE_RO_COMPAT_HAS_SNAPSHOT	0x0080
709 #define EXT4_FEATURE_RO_COMPAT_QUOTA		0x0100
710 #define EXT4_FEATURE_RO_COMPAT_BIGALLOC		0x0200
711 #define EXT4_FEATURE_RO_COMPAT_METADATA_CSUM	0x0400
712 #define EXT4_FEATURE_RO_COMPAT_REPLICA		0x0800
713 
714 #define EXT2_FEATURE_INCOMPAT_COMPRESSION	0x0001
715 #define EXT2_FEATURE_INCOMPAT_FILETYPE		0x0002
716 #define EXT3_FEATURE_INCOMPAT_RECOVER		0x0004 /* Needs recovery */
717 #define EXT3_FEATURE_INCOMPAT_JOURNAL_DEV	0x0008 /* Journal device */
718 #define EXT2_FEATURE_INCOMPAT_META_BG		0x0010
719 #define EXT3_FEATURE_INCOMPAT_EXTENTS		0x0040
720 #define EXT4_FEATURE_INCOMPAT_64BIT		0x0080
721 #define EXT4_FEATURE_INCOMPAT_MMP		0x0100
722 #define EXT4_FEATURE_INCOMPAT_FLEX_BG		0x0200
723 #define EXT4_FEATURE_INCOMPAT_EA_INODE		0x0400
724 #define EXT4_FEATURE_INCOMPAT_DIRDATA		0x1000
725 /* 0x2000 was EXT4_FEATURE_INCOMPAT_BG_USE_META_CSUM but this was never used */
726 #define EXT4_FEATURE_INCOMPAT_LARGEDIR		0x4000 /* >2GB or 3-lvl htree */
727 #define EXT4_FEATURE_INCOMPAT_INLINEDATA	0x8000 /* data in inode */
728 
729 #define EXT2_FEATURE_COMPAT_SUPP	0
730 #define EXT2_FEATURE_INCOMPAT_SUPP    (EXT2_FEATURE_INCOMPAT_FILETYPE| \
731 				       EXT4_FEATURE_INCOMPAT_MMP)
732 #define EXT2_FEATURE_RO_COMPAT_SUPP	(EXT2_FEATURE_RO_COMPAT_SPARSE_SUPER| \
733 					 EXT2_FEATURE_RO_COMPAT_LARGE_FILE| \
734 					 EXT4_FEATURE_RO_COMPAT_DIR_NLINK| \
735 					 EXT2_FEATURE_RO_COMPAT_BTREE_DIR)
736 
737 /*
738  * Default values for user and/or group using reserved blocks
739  */
740 #define EXT2_DEF_RESUID		0
741 #define EXT2_DEF_RESGID		0
742 
743 /*
744  * Default mount options
745  */
746 #define EXT2_DEFM_DEBUG		0x0001
747 #define EXT2_DEFM_BSDGROUPS	0x0002
748 #define EXT2_DEFM_XATTR_USER	0x0004
749 #define EXT2_DEFM_ACL		0x0008
750 #define EXT2_DEFM_UID16		0x0010
751 #define EXT3_DEFM_JMODE		0x0060
752 #define EXT3_DEFM_JMODE_DATA	0x0020
753 #define EXT3_DEFM_JMODE_ORDERED	0x0040
754 #define EXT3_DEFM_JMODE_WBACK	0x0060
755 #define EXT4_DEFM_NOBARRIER	0x0100
756 #define EXT4_DEFM_BLOCK_VALIDITY 0x0200
757 #define EXT4_DEFM_DISCARD	0x0400
758 #define EXT4_DEFM_NODELALLOC	0x0800
759 
760 /*
761  * Structure of a directory entry
762  */
763 #define EXT2_NAME_LEN 255
764 
765 struct ext2_dir_entry {
766 	__u32	inode;			/* Inode number */
767 	__u16	rec_len;		/* Directory entry length */
768 	__u16	name_len;		/* Name length */
769 	char	name[EXT2_NAME_LEN];	/* File name */
770 };
771 
772 /*
773  * The new version of the directory entry.  Since EXT2 structures are
774  * stored in intel byte order, and the name_len field could never be
775  * bigger than 255 chars, it's safe to reclaim the extra byte for the
776  * file_type field.
777  */
778 struct ext2_dir_entry_2 {
779 	__u32	inode;			/* Inode number */
780 	__u16	rec_len;		/* Directory entry length */
781 	__u8	name_len;		/* Name length */
782 	__u8	file_type;
783 	char	name[EXT2_NAME_LEN];	/* File name */
784 };
785 
786 /*
787  * Ext2 directory file types.  Only the low 3 bits are used.  The
788  * other bits are reserved for now.
789  */
790 #define EXT2_FT_UNKNOWN		0
791 #define EXT2_FT_REG_FILE	1
792 #define EXT2_FT_DIR		2
793 #define EXT2_FT_CHRDEV		3
794 #define EXT2_FT_BLKDEV		4
795 #define EXT2_FT_FIFO		5
796 #define EXT2_FT_SOCK		6
797 #define EXT2_FT_SYMLINK		7
798 
799 #define EXT2_FT_MAX		8
800 
801 /*
802  * EXT2_DIR_PAD defines the directory entries boundaries
803  *
804  * NOTE: It must be a multiple of 4
805  */
806 #define EXT2_DIR_PAD			4
807 #define EXT2_DIR_ROUND			(EXT2_DIR_PAD - 1)
808 #define EXT2_DIR_REC_LEN(name_len)	(((name_len) + 8 + EXT2_DIR_ROUND) & \
809 					 ~EXT2_DIR_ROUND)
810 
811 /*
812  * This structure is used for multiple mount protection. It is written
813  * into the block number saved in the s_mmp_block field in the superblock.
814  * Programs that check MMP should assume that if SEQ_FSCK (or any unknown
815  * code above SEQ_MAX) is present then it is NOT safe to use the filesystem,
816  * regardless of how old the timestamp is.
817  *
818  * The timestamp in the MMP structure will be updated by e2fsck at some
819  * arbitary intervals (start of passes, after every few groups of inodes
820  * in pass1 and pass1b).  There is no guarantee that e2fsck is updating
821  * the MMP block in a timely manner, and the updates it does are purely
822  * for the convenience of the sysadmin and not for automatic validation.
823  *
824  * Note: Only the mmp_seq value is used to determine whether the MMP block
825  *	is being updated.  The mmp_time, mmp_nodename, and mmp_bdevname
826  *	fields are only for informational purposes for the administrator,
827  *	due to clock skew between nodes and hostname HA service takeover.
828  */
829 #define EXT4_MMP_MAGIC     0x004D4D50U /* ASCII for MMP */
830 #define EXT4_MMP_SEQ_CLEAN 0xFF4D4D50U /* mmp_seq value for clean unmount */
831 #define EXT4_MMP_SEQ_FSCK  0xE24D4D50U /* mmp_seq value when being fscked */
832 #define EXT4_MMP_SEQ_MAX   0xE24D4D4FU /* maximum valid mmp_seq value */
833 
834 struct mmp_struct {
835 	__u32	mmp_magic;		/* Magic number for MMP */
836 	__u32	mmp_seq;		/* Sequence no. updated periodically */
837 	__u64	mmp_time;		/* Time last updated */
838 	char	mmp_nodename[64];	/* Node which last updated MMP block */
839 	char	mmp_bdevname[32];	/* Bdev which last updated MMP block */
840 	__u16	mmp_check_interval;	/* Changed mmp_check_interval */
841 	__u16	mmp_pad1;
842 	__u32	mmp_pad2[227];
843 };
844 
845 /*
846  * Default interval for MMP update in seconds.
847  */
848 #define EXT4_MMP_UPDATE_INTERVAL	5
849 
850 /*
851  * Maximum interval for MMP update in seconds.
852  */
853 #define EXT4_MMP_MAX_UPDATE_INTERVAL	300
854 
855 /*
856  * Minimum interval for MMP checking in seconds.
857  */
858 #define EXT4_MMP_MIN_CHECK_INTERVAL     5
859 
860 #endif	/* _LINUX_EXT2_FS_H */
861