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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 EXT4_BG_INODE_BITMAP_CSUM_HI_END	\
196 	(offsetof(struct ext4_group_desc, bg_inode_bitmap_csum_hi) + \
197 	 sizeof(__u16))
198 #define EXT4_BG_BLOCK_BITMAP_CSUM_HI_LOCATION	\
199 	(offsetof(struct ext4_group_desc, bg_block_bitmap_csum_hi) + \
200 	 sizeof(__u16))
201 
202 #define EXT2_BG_INODE_UNINIT	0x0001 /* Inode table/bitmap not initialized */
203 #define EXT2_BG_BLOCK_UNINIT	0x0002 /* Block bitmap not initialized */
204 #define EXT2_BG_INODE_ZEROED	0x0004 /* On-disk itable initialized to zero */
205 
206 /*
207  * Data structures used by the directory indexing feature
208  *
209  * Note: all of the multibyte integer fields are little endian.
210  */
211 
212 /*
213  * Note: dx_root_info is laid out so that if it should somehow get
214  * overlaid by a dirent the two low bits of the hash version will be
215  * zero.  Therefore, the hash version mod 4 should never be 0.
216  * Sincerely, the paranoia department.
217  */
218 struct ext2_dx_root_info {
219 	__u32 reserved_zero;
220 	__u8 hash_version; /* 0 now, 1 at release */
221 	__u8 info_length; /* 8 */
222 	__u8 indirect_levels;
223 	__u8 unused_flags;
224 };
225 
226 #define EXT2_HASH_LEGACY		0
227 #define EXT2_HASH_HALF_MD4		1
228 #define EXT2_HASH_TEA			2
229 #define EXT2_HASH_LEGACY_UNSIGNED	3 /* reserved for userspace lib */
230 #define EXT2_HASH_HALF_MD4_UNSIGNED	4 /* reserved for userspace lib */
231 #define EXT2_HASH_TEA_UNSIGNED		5 /* reserved for userspace lib */
232 
233 #define EXT2_HASH_FLAG_INCOMPAT	0x1
234 
235 struct ext2_dx_entry {
236 	__le32 hash;
237 	__le32 block;
238 };
239 
240 struct ext2_dx_countlimit {
241 	__le16 limit;
242 	__le16 count;
243 };
244 
245 /*
246  * This goes at the end of each htree block.
247  */
248 struct ext2_dx_tail {
249 	__le32 dt_reserved;
250 	__le32 dt_checksum;	/* crc32c(uuid+inum+dxblock) */
251 };
252 
253 /*
254  * Macro-instructions used to manage group descriptors
255  */
256 #define EXT2_MIN_DESC_SIZE             32
257 #define EXT2_MIN_DESC_SIZE_64BIT       64
258 #define EXT2_MAX_DESC_SIZE             EXT2_MIN_BLOCK_SIZE
259 #define EXT2_DESC_SIZE(s)                                                \
260        ((EXT2_SB(s)->s_feature_incompat & EXT4_FEATURE_INCOMPAT_64BIT) ? \
261 	(s)->s_desc_size : EXT2_MIN_DESC_SIZE)
262 
263 #define EXT2_BLOCKS_PER_GROUP(s)	(EXT2_SB(s)->s_blocks_per_group)
264 #define EXT2_INODES_PER_GROUP(s)	(EXT2_SB(s)->s_inodes_per_group)
265 #define EXT2_CLUSTERS_PER_GROUP(s)	(EXT2_SB(s)->s_clusters_per_group)
266 #define EXT2_INODES_PER_BLOCK(s)	(EXT2_BLOCK_SIZE(s)/EXT2_INODE_SIZE(s))
267 /* limits imposed by 16-bit value gd_free_{blocks,inode}_count */
268 #define EXT2_MAX_BLOCKS_PER_GROUP(s)	((((unsigned) 1 << 16) - 8) *	\
269 					 (EXT2_CLUSTER_SIZE(s) / \
270 					  EXT2_BLOCK_SIZE(s)))
271 #define EXT2_MAX_CLUSTERS_PER_GROUP(s)	(((unsigned) 1 << 16) - 8)
272 #define EXT2_MAX_INODES_PER_GROUP(s)	(((unsigned) 1 << 16) - \
273 					 EXT2_INODES_PER_BLOCK(s))
274 #ifdef __KERNEL__
275 #define EXT2_DESC_PER_BLOCK(s)		(EXT2_SB(s)->s_desc_per_block)
276 #define EXT2_DESC_PER_BLOCK_BITS(s)	(EXT2_SB(s)->s_desc_per_block_bits)
277 #else
278 #define EXT2_DESC_PER_BLOCK(s)		(EXT2_BLOCK_SIZE(s) / EXT2_DESC_SIZE(s))
279 #endif
280 
281 #define EXT2_GROUPS_TO_BLOCKS(s, g)   ((blk64_t) EXT2_BLOCKS_PER_GROUP(s) * \
282 				       (g))
283 #define EXT2_GROUPS_TO_CLUSTERS(s, g) ((blk64_t) EXT2_CLUSTERS_PER_GROUP(s) * \
284 				       (g))
285 
286 /*
287  * Constants relative to the data blocks
288  */
289 #define EXT2_NDIR_BLOCKS		12
290 #define EXT2_IND_BLOCK			EXT2_NDIR_BLOCKS
291 #define EXT2_DIND_BLOCK			(EXT2_IND_BLOCK + 1)
292 #define EXT2_TIND_BLOCK			(EXT2_DIND_BLOCK + 1)
293 #define EXT2_N_BLOCKS			(EXT2_TIND_BLOCK + 1)
294 
295 /*
296  * Inode flags
297  */
298 #define EXT2_SECRM_FL			0x00000001 /* Secure deletion */
299 #define EXT2_UNRM_FL			0x00000002 /* Undelete */
300 #define EXT2_COMPR_FL			0x00000004 /* Compress file */
301 #define EXT2_SYNC_FL			0x00000008 /* Synchronous updates */
302 #define EXT2_IMMUTABLE_FL		0x00000010 /* Immutable file */
303 #define EXT2_APPEND_FL			0x00000020 /* writes to file may only append */
304 #define EXT2_NODUMP_FL			0x00000040 /* do not dump file */
305 #define EXT2_NOATIME_FL			0x00000080 /* do not update atime */
306 /* Reserved for compression usage... */
307 #define EXT2_DIRTY_FL			0x00000100
308 #define EXT2_COMPRBLK_FL		0x00000200 /* One or more compressed clusters */
309 #define EXT2_NOCOMPR_FL			0x00000400 /* Access raw compressed data */
310 	/* nb: was previously EXT2_ECOMPR_FL */
311 #define EXT4_ENCRYPT_FL			0x00000800 /* encrypted inode */
312 /* End compression flags --- maybe not all used */
313 #define EXT2_BTREE_FL			0x00001000 /* btree format dir */
314 #define EXT2_INDEX_FL			0x00001000 /* hash-indexed directory */
315 #define EXT2_IMAGIC_FL			0x00002000
316 #define EXT3_JOURNAL_DATA_FL		0x00004000 /* file data should be journaled */
317 #define EXT2_NOTAIL_FL			0x00008000 /* file tail should not be merged */
318 #define EXT2_DIRSYNC_FL 		0x00010000 /* Synchronous directory modifications */
319 #define EXT2_TOPDIR_FL			0x00020000 /* Top of directory hierarchies*/
320 #define EXT4_HUGE_FILE_FL               0x00040000 /* Set to each huge file */
321 #define EXT4_EXTENTS_FL 		0x00080000 /* Inode uses extents */
322 #define EXT4_EA_INODE_FL	        0x00200000 /* Inode used for large EA */
323 /* EXT4_EOFBLOCKS_FL 0x00400000 was here */
324 #define FS_NOCOW_FL			0x00800000 /* Do not cow file */
325 #define EXT4_SNAPFILE_FL		0x01000000  /* Inode is a snapshot */
326 #define EXT4_SNAPFILE_DELETED_FL	0x04000000  /* Snapshot is being deleted */
327 #define EXT4_SNAPFILE_SHRUNK_FL		0x08000000  /* Snapshot shrink has completed */
328 #define EXT4_INLINE_DATA_FL		0x10000000 /* Inode has inline data */
329 #define EXT4_PROJINHERIT_FL		0x20000000 /* Create with parents projid */
330 #define EXT2_RESERVED_FL		0x80000000 /* reserved for ext2 lib */
331 
332 #define EXT2_FL_USER_VISIBLE		0x204BDFFF /* User visible flags */
333 #define EXT2_FL_USER_MODIFIABLE		0x204B80FF /* User modifiable flags */
334 
335 /*
336  * ioctl commands
337  */
338 
339 /* Used for online resize */
340 struct ext2_new_group_input {
341 	__u32 group;		/* Group number for this data */
342 	__u32 block_bitmap;	/* Absolute block number of block bitmap */
343 	__u32 inode_bitmap;	/* Absolute block number of inode bitmap */
344 	__u32 inode_table;	/* Absolute block number of inode table start */
345 	__u32 blocks_count;	/* Total number of blocks in this group */
346 	__u16 reserved_blocks;	/* Number of reserved blocks in this group */
347 	__u16 unused;		/* Number of reserved GDT blocks in group */
348 };
349 
350 struct ext4_new_group_input {
351 	__u32 group;		/* Group number for this data */
352 	__u64 block_bitmap;	/* Absolute block number of block bitmap */
353 	__u64 inode_bitmap;	/* Absolute block number of inode bitmap */
354 	__u64 inode_table;	/* Absolute block number of inode table start */
355 	__u32 blocks_count;	/* Total number of blocks in this group */
356 	__u16 reserved_blocks;	/* Number of reserved blocks in this group */
357 	__u16 unused;
358 };
359 
360 #ifdef __GNU__			/* Needed for the Hurd */
361 #define _IOT_ext2_new_group_input _IOT (_IOTS(__u32), 5, _IOTS(__u16), 2, 0, 0)
362 #endif
363 
364 #define EXT2_IOC_GETFLAGS		_IOR('f', 1, long)
365 #define EXT2_IOC_SETFLAGS		_IOW('f', 2, long)
366 #define EXT2_IOC_GETVERSION		_IOR('v', 1, long)
367 #define EXT2_IOC_SETVERSION		_IOW('v', 2, long)
368 #define EXT2_IOC_GETVERSION_NEW		_IOR('f', 3, long)
369 #define EXT2_IOC_SETVERSION_NEW		_IOW('f', 4, long)
370 #define EXT2_IOC_GROUP_EXTEND		_IOW('f', 7, unsigned long)
371 #define EXT2_IOC_GROUP_ADD		_IOW('f', 8,struct ext2_new_group_input)
372 #define EXT4_IOC_GROUP_ADD		_IOW('f', 8,struct ext4_new_group_input)
373 #define EXT4_IOC_RESIZE_FS		_IOW('f', 16, __u64)
374 
375 /*
376  * Structure of an inode on the disk
377  */
378 struct ext2_inode {
379 	__u16	i_mode;		/* File mode */
380 	__u16	i_uid;		/* Low 16 bits of Owner Uid */
381 	__u32	i_size;		/* Size in bytes */
382 	__u32	i_atime;	/* Access time */
383 	__u32	i_ctime;	/* Inode change time */
384 	__u32	i_mtime;	/* Modification time */
385 	__u32	i_dtime;	/* Deletion Time */
386 	__u16	i_gid;		/* Low 16 bits of Group Id */
387 	__u16	i_links_count;	/* Links count */
388 	__u32	i_blocks;	/* Blocks count */
389 	__u32	i_flags;	/* File flags */
390 	union {
391 		struct {
392 			__u32	l_i_version; /* was l_i_reserved1 */
393 		} linux1;
394 		struct {
395 			__u32  h_i_translator;
396 		} hurd1;
397 	} osd1;				/* OS dependent 1 */
398 	__u32	i_block[EXT2_N_BLOCKS];/* Pointers to blocks */
399 	__u32	i_generation;	/* File version (for NFS) */
400 	__u32	i_file_acl;	/* File ACL */
401 	__u32	i_size_high;	/* Formerly i_dir_acl, directory ACL */
402 	__u32	i_faddr;	/* Fragment address */
403 	union {
404 		struct {
405 			__u16	l_i_blocks_hi;
406 			__u16	l_i_file_acl_high;
407 			__u16	l_i_uid_high;	/* these 2 fields    */
408 			__u16	l_i_gid_high;	/* were reserved2[0] */
409 			__u16	l_i_checksum_lo; /* crc32c(uuid+inum+inode) */
410 			__u16	l_i_reserved;
411 		} linux2;
412 		struct {
413 			__u8	h_i_frag;	/* Fragment number */
414 			__u8	h_i_fsize;	/* Fragment size */
415 			__u16	h_i_mode_high;
416 			__u16	h_i_uid_high;
417 			__u16	h_i_gid_high;
418 			__u32	h_i_author;
419 		} hurd2;
420 	} osd2;				/* OS dependent 2 */
421 };
422 
423 /*
424  * Permanent part of an large inode on the disk
425  */
426 struct ext2_inode_large {
427 	__u16	i_mode;		/* File mode */
428 	__u16	i_uid;		/* Low 16 bits of Owner Uid */
429 	__u32	i_size;		/* Size in bytes */
430 	__u32	i_atime;	/* Access time */
431 	__u32	i_ctime;	/* Inode Change time */
432 	__u32	i_mtime;	/* Modification time */
433 	__u32	i_dtime;	/* Deletion Time */
434 	__u16	i_gid;		/* Low 16 bits of Group Id */
435 	__u16	i_links_count;	/* Links count */
436 	__u32	i_blocks;	/* Blocks count */
437 	__u32	i_flags;	/* File flags */
438 	union {
439 		struct {
440 			__u32	l_i_version; /* was l_i_reserved1 */
441 		} linux1;
442 		struct {
443 			__u32  h_i_translator;
444 		} hurd1;
445 	} osd1;				/* OS dependent 1 */
446 	__u32	i_block[EXT2_N_BLOCKS];/* Pointers to blocks */
447 	__u32	i_generation;	/* File version (for NFS) */
448 	__u32	i_file_acl;	/* File ACL */
449 	__u32	i_size_high;	/* Formerly i_dir_acl, directory ACL */
450 	__u32	i_faddr;	/* Fragment address */
451 	union {
452 		struct {
453 			__u16	l_i_blocks_hi;
454 			__u16	l_i_file_acl_high;
455 			__u16	l_i_uid_high;	/* these 2 fields    */
456 			__u16	l_i_gid_high;	/* were reserved2[0] */
457 			__u16	l_i_checksum_lo; /* crc32c(uuid+inum+inode) */
458 			__u16	l_i_reserved;
459 		} linux2;
460 		struct {
461 			__u8	h_i_frag;	/* Fragment number */
462 			__u8	h_i_fsize;	/* Fragment size */
463 			__u16	h_i_mode_high;
464 			__u16	h_i_uid_high;
465 			__u16	h_i_gid_high;
466 			__u32	h_i_author;
467 		} hurd2;
468 	} osd2;				/* OS dependent 2 */
469 	__u16	i_extra_isize;
470 	__u16	i_checksum_hi;	/* crc32c(uuid+inum+inode) */
471 	__u32	i_ctime_extra;	/* extra Change time (nsec << 2 | epoch) */
472 	__u32	i_mtime_extra;	/* extra Modification time (nsec << 2 | epoch) */
473 	__u32	i_atime_extra;	/* extra Access time (nsec << 2 | epoch) */
474 	__u32	i_crtime;	/* File creation time */
475 	__u32	i_crtime_extra;	/* extra File creation time (nsec << 2 | epoch)*/
476 	__u32	i_version_hi;	/* high 32 bits for 64-bit version */
477 	__u32   i_projid;       /* Project ID */
478 };
479 
480 #define EXT4_INODE_CSUM_HI_EXTRA_END	\
481 	(offsetof(struct ext2_inode_large, i_checksum_hi) + sizeof(__u16) - \
482 	 EXT2_GOOD_OLD_INODE_SIZE)
483 
484 #define EXT4_EPOCH_BITS 2
485 #define EXT4_EPOCH_MASK ((1 << EXT4_EPOCH_BITS) - 1)
486 
487 #define i_dir_acl	i_size_high
488 
489 #define i_checksum_lo	osd2.linux2.l_i_checksum_lo
490 
491 #define inode_includes(size, field)			\
492        (size >= (sizeof(((struct ext2_inode_large *)0)->field) + \
493                  offsetof(struct ext2_inode_large, field)))
494 
495 #if defined(__KERNEL__) || defined(__linux__)
496 #define i_reserved1	osd1.linux1.l_i_reserved1
497 #define i_frag		osd2.linux2.l_i_frag
498 #define i_fsize		osd2.linux2.l_i_fsize
499 #define i_uid_low	i_uid
500 #define i_gid_low	i_gid
501 #define i_uid_high	osd2.linux2.l_i_uid_high
502 #define i_gid_high	osd2.linux2.l_i_gid_high
503 #else
504 #if defined(__GNU__)
505 
506 #define i_translator	osd1.hurd1.h_i_translator
507 #define i_frag		osd2.hurd2.h_i_frag;
508 #define i_fsize		osd2.hurd2.h_i_fsize;
509 #define i_uid_high	osd2.hurd2.h_i_uid_high
510 #define i_gid_high	osd2.hurd2.h_i_gid_high
511 #define i_author	osd2.hurd2.h_i_author
512 
513 #endif  /* __GNU__ */
514 #endif	/* defined(__KERNEL__) || defined(__linux__) */
515 
516 #define inode_uid(inode)	((inode).i_uid | (inode).osd2.linux2.l_i_uid_high << 16)
517 #define inode_gid(inode)	((inode).i_gid | (inode).osd2.linux2.l_i_gid_high << 16)
518 #define inode_projid(inode)	((inode).i_projid)
519 #define ext2fs_set_i_uid_high(inode,x) ((inode).osd2.linux2.l_i_uid_high = (x))
520 #define ext2fs_set_i_gid_high(inode,x) ((inode).osd2.linux2.l_i_gid_high = (x))
521 
522 static inline
EXT2_INODE(struct ext2_inode_large * large_inode)523 struct ext2_inode *EXT2_INODE(struct ext2_inode_large *large_inode)
524 {
525 	return (struct ext2_inode *) large_inode;
526 }
527 
528 /*
529  * File system states
530  */
531 #define EXT2_VALID_FS			0x0001	/* Unmounted cleanly */
532 #define EXT2_ERROR_FS			0x0002	/* Errors detected */
533 #define EXT3_ORPHAN_FS			0x0004	/* Orphans being recovered */
534 
535 /*
536  * Misc. filesystem flags
537  */
538 #define EXT2_FLAGS_SIGNED_HASH		0x0001  /* Signed dirhash in use */
539 #define EXT2_FLAGS_UNSIGNED_HASH	0x0002  /* Unsigned dirhash in use */
540 #define EXT2_FLAGS_TEST_FILESYS		0x0004	/* OK for use on development code */
541 #define EXT2_FLAGS_IS_SNAPSHOT		0x0010	/* This is a snapshot image */
542 #define EXT2_FLAGS_FIX_SNAPSHOT		0x0020	/* Snapshot inodes corrupted */
543 #define EXT2_FLAGS_FIX_EXCLUDE		0x0040	/* Exclude bitmaps corrupted */
544 
545 /*
546  * Mount flags
547  */
548 #define EXT2_MOUNT_CHECK		0x0001	/* Do mount-time checks */
549 #define EXT2_MOUNT_GRPID		0x0004	/* Create files with directory's group */
550 #define EXT2_MOUNT_DEBUG		0x0008	/* Some debugging messages */
551 #define EXT2_MOUNT_ERRORS_CONT		0x0010	/* Continue on errors */
552 #define EXT2_MOUNT_ERRORS_RO		0x0020	/* Remount fs ro on errors */
553 #define EXT2_MOUNT_ERRORS_PANIC		0x0040	/* Panic on errors */
554 #define EXT2_MOUNT_MINIX_DF		0x0080	/* Mimics the Minix statfs */
555 #define EXT2_MOUNT_NO_UID32		0x0200  /* Disable 32-bit UIDs */
556 
557 #define clear_opt(o, opt)		o &= ~EXT2_MOUNT_##opt
558 #define set_opt(o, opt)			o |= EXT2_MOUNT_##opt
559 #define test_opt(sb, opt)		(EXT2_SB(sb)->s_mount_opt & \
560 					 EXT2_MOUNT_##opt)
561 /*
562  * Maximal mount counts between two filesystem checks
563  */
564 #define EXT2_DFL_MAX_MNT_COUNT		20	/* Allow 20 mounts */
565 #define EXT2_DFL_CHECKINTERVAL		0	/* Don't use interval check */
566 
567 /*
568  * Behaviour when detecting errors
569  */
570 #define EXT2_ERRORS_CONTINUE		1	/* Continue execution */
571 #define EXT2_ERRORS_RO			2	/* Remount fs read-only */
572 #define EXT2_ERRORS_PANIC		3	/* Panic */
573 #define EXT2_ERRORS_DEFAULT		EXT2_ERRORS_CONTINUE
574 
575 #if (__GNUC__ >= 4)
576 #define ext4_offsetof(TYPE,MEMBER) __builtin_offsetof(TYPE,MEMBER)
577 #else
578 #define ext4_offsetof(TYPE, MEMBER) ((size_t) &((TYPE *)0)->MEMBER)
579 #endif
580 
581 /* Metadata checksum algorithms */
582 #define EXT2_CRC32C_CHKSUM		1
583 
584 /* Encryption algorithms, key size and key reference len */
585 #define EXT4_ENCRYPTION_MODE_INVALID		0
586 #define EXT4_ENCRYPTION_MODE_AES_256_XTS	1
587 #define EXT4_ENCRYPTION_MODE_AES_256_GCM	2
588 #define EXT4_ENCRYPTION_MODE_AES_256_CBC	3
589 #define EXT4_ENCRYPTION_MODE_AES_256_CTS	4
590 
591 #define EXT4_AES_256_XTS_KEY_SIZE		64
592 #define EXT4_AES_256_GCM_KEY_SIZE		32
593 #define EXT4_AES_256_CBC_KEY_SIZE		32
594 #define EXT4_AES_256_CTS_KEY_SIZE		32
595 #define EXT4_MAX_KEY_SIZE			64
596 
597 #define EXT4_KEY_DESCRIPTOR_SIZE		8
598 #define EXT4_CRYPTO_BLOCK_SIZE			16
599 
600 /* Password derivation constants */
601 #define EXT4_MAX_PASSPHRASE_SIZE		1024
602 #define EXT4_MAX_SALT_SIZE			256
603 #define EXT4_PBKDF2_ITERATIONS			0xFFFF
604 
605 #define EXT2_LABEL_LEN				16
606 
607 /*
608  * Policy provided via an ioctl on the topmost directory. This
609  * structure is also in the kernel.
610  */
611 struct ext4_encryption_policy {
612   char version;
613   char contents_encryption_mode;
614   char filenames_encryption_mode;
615   char flags;
616   char master_key_descriptor[EXT4_KEY_DESCRIPTOR_SIZE];
617 } __attribute__((__packed__));
618 
619 struct ext4_encryption_key {
620         __u32 mode;
621         char raw[EXT4_MAX_KEY_SIZE];
622         __u32 size;
623 } __attribute__((__packed__));
624 
625 /*
626  * Structure of the super block
627  */
628 struct ext2_super_block {
629 	__u32	s_inodes_count;		/* Inodes count */
630 	__u32	s_blocks_count;		/* Blocks count */
631 	__u32	s_r_blocks_count;	/* Reserved blocks count */
632 	__u32	s_free_blocks_count;	/* Free blocks count */
633 	__u32	s_free_inodes_count;	/* Free inodes count */
634 	__u32	s_first_data_block;	/* First Data Block */
635 	__u32	s_log_block_size;	/* Block size */
636 	__u32	s_log_cluster_size;	/* Allocation cluster size */
637 	__u32	s_blocks_per_group;	/* # Blocks per group */
638 	__u32	s_clusters_per_group;	/* # Fragments per group */
639 	__u32	s_inodes_per_group;	/* # Inodes per group */
640 	__u32	s_mtime;		/* Mount time */
641 	__u32	s_wtime;		/* Write time */
642 	__u16	s_mnt_count;		/* Mount count */
643 	__s16	s_max_mnt_count;	/* Maximal mount count */
644 	__u16	s_magic;		/* Magic signature */
645 	__u16	s_state;		/* File system state */
646 	__u16	s_errors;		/* Behaviour when detecting errors */
647 	__u16	s_minor_rev_level;	/* minor revision level */
648 	__u32	s_lastcheck;		/* time of last check */
649 	__u32	s_checkinterval;	/* max. time between checks */
650 	__u32	s_creator_os;		/* OS */
651 	__u32	s_rev_level;		/* Revision level */
652 	__u16	s_def_resuid;		/* Default uid for reserved blocks */
653 	__u16	s_def_resgid;		/* Default gid for reserved blocks */
654 	/*
655 	 * These fields are for EXT2_DYNAMIC_REV superblocks only.
656 	 *
657 	 * Note: the difference between the compatible feature set and
658 	 * the incompatible feature set is that if there is a bit set
659 	 * in the incompatible feature set that the kernel doesn't
660 	 * know about, it should refuse to mount the filesystem.
661 	 *
662 	 * e2fsck's requirements are more strict; if it doesn't know
663 	 * about a feature in either the compatible or incompatible
664 	 * feature set, it must abort and not try to meddle with
665 	 * things it doesn't understand...
666 	 */
667 	__u32	s_first_ino;		/* First non-reserved inode */
668 	__u16   s_inode_size;		/* size of inode structure */
669 	__u16	s_block_group_nr;	/* block group # of this superblock */
670 	__u32	s_feature_compat;	/* compatible feature set */
671 	__u32	s_feature_incompat;	/* incompatible feature set */
672 	__u32	s_feature_ro_compat;	/* readonly-compatible feature set */
673 	__u8	s_uuid[16];		/* 128-bit uuid for volume */
674 	char	s_volume_name[EXT2_LABEL_LEN];	/* volume name */
675 	char	s_last_mounted[64];	/* directory where last mounted */
676 	__u32	s_algorithm_usage_bitmap; /* For compression */
677 	/*
678 	 * Performance hints.  Directory preallocation should only
679 	 * happen if the EXT2_FEATURE_COMPAT_DIR_PREALLOC flag is on.
680 	 */
681 	__u8	s_prealloc_blocks;	/* Nr of blocks to try to preallocate*/
682 	__u8	s_prealloc_dir_blocks;	/* Nr to preallocate for dirs */
683 	__u16	s_reserved_gdt_blocks;	/* Per group table for online growth */
684 	/*
685 	 * Journaling support valid if EXT2_FEATURE_COMPAT_HAS_JOURNAL set.
686 	 */
687 	__u8	s_journal_uuid[16];	/* uuid of journal superblock */
688 	__u32	s_journal_inum;		/* inode number of journal file */
689 	__u32	s_journal_dev;		/* device number of journal file */
690 	__u32	s_last_orphan;		/* start of list of inodes to delete */
691 	__u32	s_hash_seed[4];		/* HTREE hash seed */
692 	__u8	s_def_hash_version;	/* Default hash version to use */
693 	__u8	s_jnl_backup_type; 	/* Default type of journal backup */
694 	__u16	s_desc_size;		/* Group desc. size: INCOMPAT_64BIT */
695 	__u32	s_default_mount_opts;
696 	__u32	s_first_meta_bg;	/* First metablock group */
697 	__u32	s_mkfs_time;		/* When the filesystem was created */
698 	__u32	s_jnl_blocks[17]; 	/* Backup of the journal inode */
699 	__u32	s_blocks_count_hi;	/* Blocks count high 32bits */
700 	__u32	s_r_blocks_count_hi;	/* Reserved blocks count high 32 bits*/
701 	__u32	s_free_blocks_hi; 	/* Free blocks count */
702 	__u16	s_min_extra_isize;	/* All inodes have at least # bytes */
703 	__u16	s_want_extra_isize; 	/* New inodes should reserve # bytes */
704 	__u32	s_flags;		/* Miscellaneous flags */
705 	__u16   s_raid_stride;		/* RAID stride */
706 	__u16   s_mmp_update_interval;  /* # seconds to wait in MMP checking */
707 	__u64   s_mmp_block;            /* Block for multi-mount protection */
708 	__u32   s_raid_stripe_width;    /* blocks on all data disks (N*stride)*/
709 	__u8	s_log_groups_per_flex;	/* FLEX_BG group size */
710 	__u8    s_checksum_type;	/* metadata checksum algorithm */
711 	__u8	s_encryption_level;	/* versioning level for encryption */
712 	__u8	s_reserved_pad;		/* Padding to next 32bits */
713 	__u64	s_kbytes_written;	/* nr of lifetime kilobytes written */
714 	__u32	s_snapshot_inum;	/* Inode number of active snapshot */
715 	__u32	s_snapshot_id;		/* sequential ID of active snapshot */
716 	__u64	s_snapshot_r_blocks_count; /* reserved blocks for active
717 					      snapshot's future use */
718 	__u32	s_snapshot_list;	/* inode number of the head of the on-disk snapshot list */
719 #define EXT4_S_ERR_START ext4_offsetof(struct ext2_super_block, s_error_count)
720 	__u32	s_error_count;		/* number of fs errors */
721 	__u32	s_first_error_time;	/* first time an error happened */
722 	__u32	s_first_error_ino;	/* inode involved in first error */
723 	__u64	s_first_error_block;	/* block involved of first error */
724 	__u8	s_first_error_func[32];	/* function where the error happened */
725 	__u32	s_first_error_line;	/* line number where error happened */
726 	__u32	s_last_error_time;	/* most recent time of an error */
727 	__u32	s_last_error_ino;	/* inode involved in last error */
728 	__u32	s_last_error_line;	/* line number where error happened */
729 	__u64	s_last_error_block;	/* block involved of last error */
730 	__u8	s_last_error_func[32];	/* function where the error happened */
731 #define EXT4_S_ERR_END ext4_offsetof(struct ext2_super_block, s_mount_opts)
732 	__u8	s_mount_opts[64];
733 	__u32	s_usr_quota_inum;	/* inode number of user quota file */
734 	__u32	s_grp_quota_inum;	/* inode number of group quota file */
735 	__u32	s_overhead_blocks;	/* overhead blocks/clusters in fs */
736 	__u32	s_backup_bgs[2];	/* If sparse_super2 enabled */
737 	__u8	s_encrypt_algos[4];	/* Encryption algorithms in use  */
738 	__u8	s_encrypt_pw_salt[16];	/* Salt used for string2key algorithm */
739 	__le32	s_lpf_ino;		/* Location of the lost+found inode */
740 	__le32  s_prj_quota_inum;	/* inode for tracking project quota */
741 	__le32	s_checksum_seed;	/* crc32c(orig_uuid) if csum_seed set */
742 	__le32	s_reserved[98];		/* Padding to the end of the block */
743 	__u32	s_checksum;		/* crc32c(superblock) */
744 };
745 
746 #define EXT4_S_ERR_LEN (EXT4_S_ERR_END - EXT4_S_ERR_START)
747 
748 /*
749  * Codes for operating systems
750  */
751 #define EXT2_OS_LINUX		0
752 #define EXT2_OS_HURD		1
753 #define EXT2_OBSO_OS_MASIX	2
754 #define EXT2_OS_FREEBSD		3
755 #define EXT2_OS_LITES		4
756 
757 /*
758  * Revision levels
759  */
760 #define EXT2_GOOD_OLD_REV	0	/* The good old (original) format */
761 #define EXT2_DYNAMIC_REV	1	/* V2 format w/ dynamic inode sizes */
762 
763 #define EXT2_CURRENT_REV	EXT2_GOOD_OLD_REV
764 #define EXT2_MAX_SUPP_REV	EXT2_DYNAMIC_REV
765 
766 #define EXT2_GOOD_OLD_INODE_SIZE 128
767 
768 /*
769  * Journal inode backup types
770  */
771 #define EXT3_JNL_BACKUP_BLOCKS	1
772 
773 /*
774  * Feature set definitions
775  */
776 
777 #define EXT2_HAS_COMPAT_FEATURE(sb,mask)			\
778 	( EXT2_SB(sb)->s_feature_compat & (mask) )
779 #define EXT2_HAS_RO_COMPAT_FEATURE(sb,mask)			\
780 	( EXT2_SB(sb)->s_feature_ro_compat & (mask) )
781 #define EXT2_HAS_INCOMPAT_FEATURE(sb,mask)			\
782 	( EXT2_SB(sb)->s_feature_incompat & (mask) )
783 
784 #define EXT2_FEATURE_COMPAT_DIR_PREALLOC	0x0001
785 #define EXT2_FEATURE_COMPAT_IMAGIC_INODES	0x0002
786 #define EXT3_FEATURE_COMPAT_HAS_JOURNAL		0x0004
787 #define EXT2_FEATURE_COMPAT_EXT_ATTR		0x0008
788 #define EXT2_FEATURE_COMPAT_RESIZE_INODE	0x0010
789 #define EXT2_FEATURE_COMPAT_DIR_INDEX		0x0020
790 #define EXT2_FEATURE_COMPAT_LAZY_BG		0x0040
791 /* #define EXT2_FEATURE_COMPAT_EXCLUDE_INODE	0x0080 not used, legacy */
792 #define EXT2_FEATURE_COMPAT_EXCLUDE_BITMAP	0x0100
793 #define EXT4_FEATURE_COMPAT_SPARSE_SUPER2	0x0200
794 
795 
796 #define EXT2_FEATURE_RO_COMPAT_SPARSE_SUPER	0x0001
797 #define EXT2_FEATURE_RO_COMPAT_LARGE_FILE	0x0002
798 /* #define EXT2_FEATURE_RO_COMPAT_BTREE_DIR	0x0004 not used */
799 #define EXT4_FEATURE_RO_COMPAT_HUGE_FILE	0x0008
800 #define EXT4_FEATURE_RO_COMPAT_GDT_CSUM		0x0010
801 #define EXT4_FEATURE_RO_COMPAT_DIR_NLINK	0x0020
802 #define EXT4_FEATURE_RO_COMPAT_EXTRA_ISIZE	0x0040
803 #define EXT4_FEATURE_RO_COMPAT_HAS_SNAPSHOT	0x0080
804 #define EXT4_FEATURE_RO_COMPAT_QUOTA		0x0100
805 #define EXT4_FEATURE_RO_COMPAT_BIGALLOC		0x0200
806 /*
807  * METADATA_CSUM implies GDT_CSUM.  When METADATA_CSUM is set, group
808  * descriptor checksums use the same algorithm as all other data
809  * structures' checksums.
810  */
811 #define EXT4_FEATURE_RO_COMPAT_METADATA_CSUM	0x0400
812 #define EXT4_FEATURE_RO_COMPAT_REPLICA		0x0800
813 #define EXT4_FEATURE_RO_COMPAT_READONLY		0x1000
814 #define EXT4_FEATURE_RO_COMPAT_PROJECT		0x2000 /* Project quota */
815 #define EXT4_FEATURE_RO_COMPAT_SHARED_BLOCKS	0x4000
816 
817 
818 #define EXT2_FEATURE_INCOMPAT_COMPRESSION	0x0001
819 #define EXT2_FEATURE_INCOMPAT_FILETYPE		0x0002
820 #define EXT3_FEATURE_INCOMPAT_RECOVER		0x0004 /* Needs recovery */
821 #define EXT3_FEATURE_INCOMPAT_JOURNAL_DEV	0x0008 /* Journal device */
822 #define EXT2_FEATURE_INCOMPAT_META_BG		0x0010
823 #define EXT3_FEATURE_INCOMPAT_EXTENTS		0x0040
824 #define EXT4_FEATURE_INCOMPAT_64BIT		0x0080
825 #define EXT4_FEATURE_INCOMPAT_MMP		0x0100
826 #define EXT4_FEATURE_INCOMPAT_FLEX_BG		0x0200
827 #define EXT4_FEATURE_INCOMPAT_EA_INODE		0x0400
828 #define EXT4_FEATURE_INCOMPAT_DIRDATA		0x1000
829 #define EXT4_FEATURE_INCOMPAT_CSUM_SEED		0x2000
830 #define EXT4_FEATURE_INCOMPAT_LARGEDIR		0x4000 /* >2GB or 3-lvl htree */
831 #define EXT4_FEATURE_INCOMPAT_INLINE_DATA	0x8000 /* data in inode */
832 #define EXT4_FEATURE_INCOMPAT_ENCRYPT		0x10000
833 
834 #define EXT4_FEATURE_COMPAT_FUNCS(name, ver, flagname) \
835 static inline int ext2fs_has_feature_##name(struct ext2_super_block *sb) \
836 { \
837 	return ((EXT2_SB(sb)->s_feature_compat & \
838 		 EXT##ver##_FEATURE_COMPAT_##flagname) != 0); \
839 } \
840 static inline void ext2fs_set_feature_##name(struct ext2_super_block *sb) \
841 { \
842 	EXT2_SB(sb)->s_feature_compat |= \
843 		EXT##ver##_FEATURE_COMPAT_##flagname; \
844 } \
845 static inline void ext2fs_clear_feature_##name(struct ext2_super_block *sb) \
846 { \
847 	EXT2_SB(sb)->s_feature_compat &= \
848 		~EXT##ver##_FEATURE_COMPAT_##flagname; \
849 }
850 
851 #define EXT4_FEATURE_RO_COMPAT_FUNCS(name, ver, flagname) \
852 static inline int ext2fs_has_feature_##name(struct ext2_super_block *sb) \
853 { \
854 	return ((EXT2_SB(sb)->s_feature_ro_compat & \
855 		 EXT##ver##_FEATURE_RO_COMPAT_##flagname) != 0); \
856 } \
857 static inline void ext2fs_set_feature_##name(struct ext2_super_block *sb) \
858 { \
859 	EXT2_SB(sb)->s_feature_ro_compat |= \
860 		EXT##ver##_FEATURE_RO_COMPAT_##flagname; \
861 } \
862 static inline void ext2fs_clear_feature_##name(struct ext2_super_block *sb) \
863 { \
864 	EXT2_SB(sb)->s_feature_ro_compat &= \
865 		~EXT##ver##_FEATURE_RO_COMPAT_##flagname; \
866 }
867 
868 #define EXT4_FEATURE_INCOMPAT_FUNCS(name, ver, flagname) \
869 static inline int ext2fs_has_feature_##name(struct ext2_super_block *sb) \
870 { \
871 	return ((EXT2_SB(sb)->s_feature_incompat & \
872 		 EXT##ver##_FEATURE_INCOMPAT_##flagname) != 0); \
873 } \
874 static inline void ext2fs_set_feature_##name(struct ext2_super_block *sb) \
875 { \
876 	EXT2_SB(sb)->s_feature_incompat |= \
877 		EXT##ver##_FEATURE_INCOMPAT_##flagname; \
878 } \
879 static inline void ext2fs_clear_feature_##name(struct ext2_super_block *sb) \
880 { \
881 	EXT2_SB(sb)->s_feature_incompat &= \
882 		~EXT##ver##_FEATURE_INCOMPAT_##flagname; \
883 }
884 
885 EXT4_FEATURE_COMPAT_FUNCS(dir_prealloc,		2, DIR_PREALLOC)
886 EXT4_FEATURE_COMPAT_FUNCS(imagic_inodes,	2, IMAGIC_INODES)
887 EXT4_FEATURE_COMPAT_FUNCS(journal,		3, HAS_JOURNAL)
888 EXT4_FEATURE_COMPAT_FUNCS(xattr,		2, EXT_ATTR)
889 EXT4_FEATURE_COMPAT_FUNCS(resize_inode,		2, RESIZE_INODE)
890 EXT4_FEATURE_COMPAT_FUNCS(dir_index,		2, DIR_INDEX)
891 EXT4_FEATURE_COMPAT_FUNCS(lazy_bg,		2, LAZY_BG)
892 EXT4_FEATURE_COMPAT_FUNCS(exclude_bitmap,	2, EXCLUDE_BITMAP)
893 EXT4_FEATURE_COMPAT_FUNCS(sparse_super2,	4, SPARSE_SUPER2)
894 
895 EXT4_FEATURE_RO_COMPAT_FUNCS(sparse_super,	2, SPARSE_SUPER)
896 EXT4_FEATURE_RO_COMPAT_FUNCS(large_file,	2, LARGE_FILE)
897 EXT4_FEATURE_RO_COMPAT_FUNCS(huge_file,		4, HUGE_FILE)
898 EXT4_FEATURE_RO_COMPAT_FUNCS(gdt_csum,		4, GDT_CSUM)
899 EXT4_FEATURE_RO_COMPAT_FUNCS(dir_nlink,		4, DIR_NLINK)
900 EXT4_FEATURE_RO_COMPAT_FUNCS(extra_isize,	4, EXTRA_ISIZE)
901 EXT4_FEATURE_RO_COMPAT_FUNCS(has_snapshot,	4, HAS_SNAPSHOT)
902 EXT4_FEATURE_RO_COMPAT_FUNCS(quota,		4, QUOTA)
903 EXT4_FEATURE_RO_COMPAT_FUNCS(bigalloc,		4, BIGALLOC)
904 EXT4_FEATURE_RO_COMPAT_FUNCS(metadata_csum,	4, METADATA_CSUM)
905 EXT4_FEATURE_RO_COMPAT_FUNCS(replica,		4, REPLICA)
906 EXT4_FEATURE_RO_COMPAT_FUNCS(readonly,		4, READONLY)
907 EXT4_FEATURE_RO_COMPAT_FUNCS(project,		4, PROJECT)
908 EXT4_FEATURE_RO_COMPAT_FUNCS(shared_blocks,	4, SHARED_BLOCKS)
909 
910 EXT4_FEATURE_INCOMPAT_FUNCS(compression,	2, COMPRESSION)
911 EXT4_FEATURE_INCOMPAT_FUNCS(filetype,		2, FILETYPE)
912 EXT4_FEATURE_INCOMPAT_FUNCS(journal_needs_recovery,	3, RECOVER)
913 EXT4_FEATURE_INCOMPAT_FUNCS(journal_dev,	3, JOURNAL_DEV)
914 EXT4_FEATURE_INCOMPAT_FUNCS(meta_bg,		2, META_BG)
915 EXT4_FEATURE_INCOMPAT_FUNCS(extents,		3, EXTENTS)
916 EXT4_FEATURE_INCOMPAT_FUNCS(64bit,		4, 64BIT)
917 EXT4_FEATURE_INCOMPAT_FUNCS(mmp,		4, MMP)
918 EXT4_FEATURE_INCOMPAT_FUNCS(flex_bg,		4, FLEX_BG)
919 EXT4_FEATURE_INCOMPAT_FUNCS(ea_inode,		4, EA_INODE)
920 EXT4_FEATURE_INCOMPAT_FUNCS(dirdata,		4, DIRDATA)
921 EXT4_FEATURE_INCOMPAT_FUNCS(csum_seed,		4, CSUM_SEED)
922 EXT4_FEATURE_INCOMPAT_FUNCS(largedir,		4, LARGEDIR)
923 EXT4_FEATURE_INCOMPAT_FUNCS(inline_data,	4, INLINE_DATA)
924 EXT4_FEATURE_INCOMPAT_FUNCS(encrypt,		4, ENCRYPT)
925 
926 #define EXT2_FEATURE_COMPAT_SUPP	0
927 #define EXT2_FEATURE_INCOMPAT_SUPP    (EXT2_FEATURE_INCOMPAT_FILETYPE| \
928 				       EXT4_FEATURE_INCOMPAT_MMP)
929 #define EXT2_FEATURE_RO_COMPAT_SUPP	(EXT2_FEATURE_RO_COMPAT_SPARSE_SUPER| \
930 					 EXT2_FEATURE_RO_COMPAT_LARGE_FILE| \
931 					 EXT4_FEATURE_RO_COMPAT_DIR_NLINK| \
932 					 EXT2_FEATURE_RO_COMPAT_BTREE_DIR)
933 
934 /*
935  * Default values for user and/or group using reserved blocks
936  */
937 #define EXT2_DEF_RESUID		0
938 #define EXT2_DEF_RESGID		0
939 
940 /*
941  * Default mount options
942  */
943 #define EXT2_DEFM_DEBUG		0x0001
944 #define EXT2_DEFM_BSDGROUPS	0x0002
945 #define EXT2_DEFM_XATTR_USER	0x0004
946 #define EXT2_DEFM_ACL		0x0008
947 #define EXT2_DEFM_UID16		0x0010
948 #define EXT3_DEFM_JMODE		0x0060
949 #define EXT3_DEFM_JMODE_DATA	0x0020
950 #define EXT3_DEFM_JMODE_ORDERED	0x0040
951 #define EXT3_DEFM_JMODE_WBACK	0x0060
952 #define EXT4_DEFM_NOBARRIER	0x0100
953 #define EXT4_DEFM_BLOCK_VALIDITY 0x0200
954 #define EXT4_DEFM_DISCARD	0x0400
955 #define EXT4_DEFM_NODELALLOC	0x0800
956 
957 /*
958  * Structure of a directory entry
959  */
960 #define EXT2_NAME_LEN 255
961 
962 struct ext2_dir_entry {
963 	__u32	inode;			/* Inode number */
964 	__u16	rec_len;		/* Directory entry length */
965 	__u16	name_len;		/* Name length */
966 	char	name[EXT2_NAME_LEN];	/* File name */
967 };
968 
969 /*
970  * The new version of the directory entry.  Since EXT2 structures are
971  * stored in intel byte order, and the name_len field could never be
972  * bigger than 255 chars, it's safe to reclaim the extra byte for the
973  * file_type field.
974  *
975  * This structure is deprecated due to endianity issues. Please use struct
976  * ext2_dir_entry and accessor functions
977  *   ext2fs_dirent_name_len
978  *   ext2fs_dirent_set_name_len
979  *   ext2fs_dirent_file_type
980  *   ext2fs_dirent_set_file_type
981  * to get and set name_len and file_type fields.
982  */
983 struct ext2_dir_entry_2 {
984 	__u32	inode;			/* Inode number */
985 	__u16	rec_len;		/* Directory entry length */
986 	__u8	name_len;		/* Name length */
987 	__u8	file_type;
988 	char	name[EXT2_NAME_LEN];	/* File name */
989 };
990 
991 /*
992  * This is a bogus directory entry at the end of each leaf block that
993  * records checksums.
994  */
995 struct ext2_dir_entry_tail {
996 	__u32	det_reserved_zero1;	/* Pretend to be unused */
997 	__u16	det_rec_len;		/* 12 */
998 	__u16	det_reserved_name_len;	/* 0xDE00, fake namelen/filetype */
999 	__u32	det_checksum;		/* crc32c(uuid+inode+dirent) */
1000 };
1001 
1002 /*
1003  * Ext2 directory file types.  Only the low 3 bits are used.  The
1004  * other bits are reserved for now.
1005  */
1006 #define EXT2_FT_UNKNOWN		0
1007 #define EXT2_FT_REG_FILE	1
1008 #define EXT2_FT_DIR		2
1009 #define EXT2_FT_CHRDEV		3
1010 #define EXT2_FT_BLKDEV		4
1011 #define EXT2_FT_FIFO		5
1012 #define EXT2_FT_SOCK		6
1013 #define EXT2_FT_SYMLINK		7
1014 
1015 #define EXT2_FT_MAX		8
1016 
1017 /*
1018  * Annoyingly, e2fsprogs always swab16s ext2_dir_entry.name_len, so we
1019  * have to build ext2_dir_entry_tail with that assumption too.  This
1020  * constant helps to build the dir_entry_tail to look like it has an
1021  * "invalid" file type.
1022  */
1023 #define EXT2_DIR_NAME_LEN_CSUM	0xDE00
1024 
1025 /*
1026  * EXT2_DIR_PAD defines the directory entries boundaries
1027  *
1028  * NOTE: It must be a multiple of 4
1029  */
1030 #define EXT2_DIR_ENTRY_HEADER_LEN	8
1031 #define EXT2_DIR_PAD			4
1032 #define EXT2_DIR_ROUND			(EXT2_DIR_PAD - 1)
1033 #define EXT2_DIR_REC_LEN(name_len)	(((name_len) + \
1034 					  EXT2_DIR_ENTRY_HEADER_LEN + \
1035 					  EXT2_DIR_ROUND) & \
1036 					 ~EXT2_DIR_ROUND)
1037 
1038 /*
1039  * Constants for ext4's extended time encoding
1040  */
1041 #define EXT4_EPOCH_BITS 2
1042 #define EXT4_EPOCH_MASK ((1 << EXT4_EPOCH_BITS) - 1)
1043 #define EXT4_NSEC_MASK  (~0UL << EXT4_EPOCH_BITS)
1044 
1045 /*
1046  * This structure is used for multiple mount protection. It is written
1047  * into the block number saved in the s_mmp_block field in the superblock.
1048  * Programs that check MMP should assume that if SEQ_FSCK (or any unknown
1049  * code above SEQ_MAX) is present then it is NOT safe to use the filesystem,
1050  * regardless of how old the timestamp is.
1051  *
1052  * The timestamp in the MMP structure will be updated by e2fsck at some
1053  * arbitary intervals (start of passes, after every few groups of inodes
1054  * in pass1 and pass1b).  There is no guarantee that e2fsck is updating
1055  * the MMP block in a timely manner, and the updates it does are purely
1056  * for the convenience of the sysadmin and not for automatic validation.
1057  *
1058  * Note: Only the mmp_seq value is used to determine whether the MMP block
1059  *	is being updated.  The mmp_time, mmp_nodename, and mmp_bdevname
1060  *	fields are only for informational purposes for the administrator,
1061  *	due to clock skew between nodes and hostname HA service takeover.
1062  */
1063 #define EXT4_MMP_MAGIC     0x004D4D50U /* ASCII for MMP */
1064 #define EXT4_MMP_SEQ_CLEAN 0xFF4D4D50U /* mmp_seq value for clean unmount */
1065 #define EXT4_MMP_SEQ_FSCK  0xE24D4D50U /* mmp_seq value when being fscked */
1066 #define EXT4_MMP_SEQ_MAX   0xE24D4D4FU /* maximum valid mmp_seq value */
1067 
1068 /* Not endian-annotated; it's swapped at read/write time */
1069 struct mmp_struct {
1070 	__u32	mmp_magic;		/* Magic number for MMP */
1071 	__u32	mmp_seq;		/* Sequence no. updated periodically */
1072 	__u64	mmp_time;		/* Time last updated */
1073 	char	mmp_nodename[64];	/* Node which last updated MMP block */
1074 	char	mmp_bdevname[32];	/* Bdev which last updated MMP block */
1075 	__u16	mmp_check_interval;	/* Changed mmp_check_interval */
1076 	__u16	mmp_pad1;
1077 	__u32	mmp_pad2[226];
1078 	__u32	mmp_checksum;		/* crc32c(uuid+mmp_block) */
1079 };
1080 
1081 /*
1082  * Default interval for MMP update in seconds.
1083  */
1084 #define EXT4_MMP_UPDATE_INTERVAL	5
1085 
1086 /*
1087  * Maximum interval for MMP update in seconds.
1088  */
1089 #define EXT4_MMP_MAX_UPDATE_INTERVAL	300
1090 
1091 /*
1092  * Minimum interval for MMP checking in seconds.
1093  */
1094 #define EXT4_MMP_MIN_CHECK_INTERVAL     5
1095 
1096 /*
1097  * Minimum size of inline data.
1098  */
1099 #define EXT4_MIN_INLINE_DATA_SIZE	((sizeof(__u32) * EXT2_N_BLOCKS))
1100 
1101 /*
1102  * Size of a parent inode in inline data directory.
1103  */
1104 #define EXT4_INLINE_DATA_DOTDOT_SIZE	(4)
1105 
1106 #endif	/* _LINUX_EXT2_FS_H */
1107