2 * linux/include/linux/ext2_fs.h
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)
11 * linux/include/linux/minix_fs.h
13 * Copyright (C) 1991, 1992 Linus Torvalds
16 #ifndef _LINUX_EXT2_FS_H
17 #define _LINUX_EXT2_FS_H
19 #include <ext2fs/ext2_types.h> /* Changed from linux/types.h */
22 * The second extended filesystem constants/structures
26 * Define EXT2FS_DEBUG to produce debug messages
31 * Define EXT2_PREALLOCATE to preallocate data blocks for expanding files
33 #define EXT2_PREALLOCATE
34 #define EXT2_DEFAULT_PREALLOC_BLOCKS 8
37 * The second extended file system version
39 #define EXT2FS_DATE "95/08/09"
40 #define EXT2FS_VERSION "0.5b"
43 * Special inode numbers
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 */
56 /* First non-reserved inode for old ext2 filesystems */
57 #define EXT2_GOOD_OLD_FIRST_INO 11
60 * The second extended file system magic number
62 #define EXT2_SUPER_MAGIC 0xEF53
65 #define EXT2_SB(sb) (&((sb)->u.ext2_sb))
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)
74 * Maximal count of links to a file
76 #define EXT2_LINK_MAX 65000
79 * Macro-instructions used to manage several block sizes
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)
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)
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)
99 #define EXT2_ADDR_PER_BLOCK(s) (EXT2_BLOCK_SIZE(s) / sizeof(__u32))
102 * Macro-instructions used to manage allocation clusters
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)
113 * Macro-instructions used to manage fragments
115 * Note: for backwards compatibility only, for the dump program.
116 * Ext2/3/4 will never support fragments....
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
127 struct ext2_acl_header /* Header of Access Control Lists */
130 __u32 aclh_file_count;
131 __u32 aclh_acle_count;
132 __u32 aclh_first_acle;
135 struct ext2_acl_entry /* Access Control List Entry */
138 __u16 acle_perms; /* Access permissions */
139 __u16 acle_type; /* Type of entry */
140 __u16 acle_tag; /* User or group identity */
142 __u32 acle_next; /* Pointer on next entry for the */
143 /* same inode or on next free entry */
147 * Structure of a blocks group descriptor
149 struct ext2_group_desc
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 */
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)*/
166 * Structure of a blocks group descriptor
168 struct ext4_group_desc
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 */
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 */
200 * Data structures used by the directory indexing feature
202 * Note: all of the multibyte integer fields are little endian.
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.
211 struct ext2_dx_root_info {
213 __u8 hash_version; /* 0 now, 1 at release */
214 __u8 info_length; /* 8 */
215 __u8 indirect_levels;
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 */
226 #define EXT2_HASH_FLAG_INCOMPAT 0x1
228 struct ext2_dx_entry {
233 struct ext2_dx_countlimit {
240 * Macro-instructions used to manage group descriptors
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)
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) / \
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))
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)
264 #define EXT2_DESC_PER_BLOCK(s) (EXT2_BLOCK_SIZE(s) / EXT2_DESC_SIZE(s))
267 #define EXT2_GROUPS_TO_BLOCKS(s, g) ((blk64_t) EXT2_BLOCKS_PER_GROUP(s) * \
269 #define EXT2_GROUPS_TO_CLUSTERS(s, g) ((blk64_t) EXT2_CLUSTERS_PER_GROUP(s) * \
273 * Constants relative to the data blocks
275 #define EXT2_NDIR_BLOCKS 12
276 #define EXT2_IND_BLOCK EXT2_NDIR_BLOCKS
277 #define EXT2_DIND_BLOCK (EXT2_IND_BLOCK + 1)
278 #define EXT2_TIND_BLOCK (EXT2_DIND_BLOCK + 1)
279 #define EXT2_N_BLOCKS (EXT2_TIND_BLOCK + 1)
284 #define EXT2_SECRM_FL 0x00000001 /* Secure deletion */
285 #define EXT2_UNRM_FL 0x00000002 /* Undelete */
286 #define EXT2_COMPR_FL 0x00000004 /* Compress file */
287 #define EXT2_SYNC_FL 0x00000008 /* Synchronous updates */
288 #define EXT2_IMMUTABLE_FL 0x00000010 /* Immutable file */
289 #define EXT2_APPEND_FL 0x00000020 /* writes to file may only append */
290 #define EXT2_NODUMP_FL 0x00000040 /* do not dump file */
291 #define EXT2_NOATIME_FL 0x00000080 /* do not update atime */
292 /* Reserved for compression usage... */
293 #define EXT2_DIRTY_FL 0x00000100
294 #define EXT2_COMPRBLK_FL 0x00000200 /* One or more compressed clusters */
295 #define EXT2_NOCOMPR_FL 0x00000400 /* Access raw compressed data */
296 #define EXT2_ECOMPR_FL 0x00000800 /* Compression error */
297 /* End compression flags --- maybe not all used */
298 #define EXT2_BTREE_FL 0x00001000 /* btree format dir */
299 #define EXT2_INDEX_FL 0x00001000 /* hash-indexed directory */
300 #define EXT2_IMAGIC_FL 0x00002000
301 #define EXT3_JOURNAL_DATA_FL 0x00004000 /* file data should be journaled */
302 #define EXT2_NOTAIL_FL 0x00008000 /* file tail should not be merged */
303 #define EXT2_DIRSYNC_FL 0x00010000 /* Synchronous directory modifications */
304 #define EXT2_TOPDIR_FL 0x00020000 /* Top of directory hierarchies*/
305 #define EXT4_HUGE_FILE_FL 0x00040000 /* Set to each huge file */
306 #define EXT4_EXTENTS_FL 0x00080000 /* Inode uses extents */
307 #define EXT4_EA_INODE_FL 0x00200000 /* Inode used for large EA */
308 /* EXT4_EOFBLOCKS_FL 0x00400000 was here */
309 #define FS_NOCOW_FL 0x00800000 /* Do not cow file */
310 #define EXT4_SNAPFILE_FL 0x01000000 /* Inode is a snapshot */
311 #define EXT4_SNAPFILE_DELETED_FL 0x04000000 /* Snapshot is being deleted */
312 #define EXT4_SNAPFILE_SHRUNK_FL 0x08000000 /* Snapshot shrink has completed */
313 #define EXT2_RESERVED_FL 0x80000000 /* reserved for ext2 lib */
315 #define EXT2_FL_USER_VISIBLE 0x004BDFFF /* User visible flags */
316 #define EXT2_FL_USER_MODIFIABLE 0x004B80FF /* User modifiable flags */
322 /* Used for online resize */
323 struct ext2_new_group_input {
324 __u32 group; /* Group number for this data */
325 __u32 block_bitmap; /* Absolute block number of block bitmap */
326 __u32 inode_bitmap; /* Absolute block number of inode bitmap */
327 __u32 inode_table; /* Absolute block number of inode table start */
328 __u32 blocks_count; /* Total number of blocks in this group */
329 __u16 reserved_blocks; /* Number of reserved blocks in this group */
330 __u16 unused; /* Number of reserved GDT blocks in group */
333 struct ext4_new_group_input {
334 __u32 group; /* Group number for this data */
335 __u64 block_bitmap; /* Absolute block number of block bitmap */
336 __u64 inode_bitmap; /* Absolute block number of inode bitmap */
337 __u64 inode_table; /* Absolute block number of inode table start */
338 __u32 blocks_count; /* Total number of blocks in this group */
339 __u16 reserved_blocks; /* Number of reserved blocks in this group */
343 #ifdef __GNU__ /* Needed for the Hurd */
344 #define _IOT_ext2_new_group_input _IOT (_IOTS(__u32), 5, _IOTS(__u16), 2, 0, 0)
347 #define EXT2_IOC_GETFLAGS _IOR('f', 1, long)
348 #define EXT2_IOC_SETFLAGS _IOW('f', 2, long)
349 #define EXT2_IOC_GETVERSION _IOR('v', 1, long)
350 #define EXT2_IOC_SETVERSION _IOW('v', 2, long)
351 #define EXT2_IOC_GETVERSION_NEW _IOR('f', 3, long)
352 #define EXT2_IOC_SETVERSION_NEW _IOW('f', 4, long)
353 #define EXT2_IOC_GROUP_EXTEND _IOW('f', 7, unsigned long)
354 #define EXT2_IOC_GROUP_ADD _IOW('f', 8,struct ext2_new_group_input)
355 #define EXT4_IOC_GROUP_ADD _IOW('f', 8,struct ext4_new_group_input)
356 #define EXT4_IOC_RESIZE_FS _IOW('f', 16, __u64)
359 * Structure of an inode on the disk
362 __u16 i_mode; /* File mode */
363 __u16 i_uid; /* Low 16 bits of Owner Uid */
364 __u32 i_size; /* Size in bytes */
365 __u32 i_atime; /* Access time */
366 __u32 i_ctime; /* Inode change time */
367 __u32 i_mtime; /* Modification time */
368 __u32 i_dtime; /* Deletion Time */
369 __u16 i_gid; /* Low 16 bits of Group Id */
370 __u16 i_links_count; /* Links count */
371 __u32 i_blocks; /* Blocks count */
372 __u32 i_flags; /* File flags */
375 __u32 l_i_version; /* was l_i_reserved1 */
378 __u32 h_i_translator;
380 } osd1; /* OS dependent 1 */
381 __u32 i_block[EXT2_N_BLOCKS];/* Pointers to blocks */
382 __u32 i_generation; /* File version (for NFS) */
383 __u32 i_file_acl; /* File ACL */
384 __u32 i_size_high; /* Formerly i_dir_acl, directory ACL */
385 __u32 i_faddr; /* Fragment address */
389 __u16 l_i_file_acl_high;
390 __u16 l_i_uid_high; /* these 2 fields */
391 __u16 l_i_gid_high; /* were reserved2[0] */
392 __u16 l_i_checksum_lo; /* crc32c(uuid+inum+inode) */
396 __u8 h_i_frag; /* Fragment number */
397 __u8 h_i_fsize; /* Fragment size */
403 } osd2; /* OS dependent 2 */
407 * Permanent part of an large inode on the disk
409 struct ext2_inode_large {
410 __u16 i_mode; /* File mode */
411 __u16 i_uid; /* Low 16 bits of Owner Uid */
412 __u32 i_size; /* Size in bytes */
413 __u32 i_atime; /* Access time */
414 __u32 i_ctime; /* Inode Change time */
415 __u32 i_mtime; /* Modification time */
416 __u32 i_dtime; /* Deletion Time */
417 __u16 i_gid; /* Low 16 bits of Group Id */
418 __u16 i_links_count; /* Links count */
419 __u32 i_blocks; /* Blocks count */
420 __u32 i_flags; /* File flags */
423 __u32 l_i_version; /* was l_i_reserved1 */
426 __u32 h_i_translator;
428 } osd1; /* OS dependent 1 */
429 __u32 i_block[EXT2_N_BLOCKS];/* Pointers to blocks */
430 __u32 i_generation; /* File version (for NFS) */
431 __u32 i_file_acl; /* File ACL */
432 __u32 i_size_high; /* Formerly i_dir_acl, directory ACL */
433 __u32 i_faddr; /* Fragment address */
437 __u16 l_i_file_acl_high;
438 __u16 l_i_uid_high; /* these 2 fields */
439 __u16 l_i_gid_high; /* were reserved2[0] */
440 __u16 l_i_checksum_lo; /* crc32c(uuid+inum+inode) */
444 __u8 h_i_frag; /* Fragment number */
445 __u8 h_i_fsize; /* Fragment size */
451 } osd2; /* OS dependent 2 */
453 __u16 i_checksum_hi; /* crc32c(uuid+inum+inode) */
454 __u32 i_ctime_extra; /* extra Change time (nsec << 2 | epoch) */
455 __u32 i_mtime_extra; /* extra Modification time (nsec << 2 | epoch) */
456 __u32 i_atime_extra; /* extra Access time (nsec << 2 | epoch) */
457 __u32 i_crtime; /* File creation time */
458 __u32 i_crtime_extra; /* extra File creation time (nsec << 2 | epoch)*/
459 __u32 i_version_hi; /* high 32 bits for 64-bit version */
462 #define i_dir_acl i_size_high
464 #define EXT2_FITS_IN_INODE(inode, field) \
465 ((offsetof(struct ext2_inode_large, field) + \
466 sizeof((inode)->field)) <= \
467 (EXT2_GOOD_OLD_INODE_SIZE + \
468 (inode)->i_extra_isize)) \
470 #if defined(__KERNEL__) || defined(__linux__)
471 #define i_reserved1 osd1.linux1.l_i_reserved1
472 #define i_frag osd2.linux2.l_i_frag
473 #define i_fsize osd2.linux2.l_i_fsize
474 #define i_uid_low i_uid
475 #define i_gid_low i_gid
476 #define i_uid_high osd2.linux2.l_i_uid_high
477 #define i_gid_high osd2.linux2.l_i_gid_high
481 #define i_translator osd1.hurd1.h_i_translator
482 #define i_frag osd2.hurd2.h_i_frag;
483 #define i_fsize osd2.hurd2.h_i_fsize;
484 #define i_uid_high osd2.hurd2.h_i_uid_high
485 #define i_gid_high osd2.hurd2.h_i_gid_high
486 #define i_author osd2.hurd2.h_i_author
489 #endif /* defined(__KERNEL__) || defined(__linux__) */
491 #define inode_uid(inode) ((inode).i_uid | (inode).osd2.linux2.l_i_uid_high << 16)
492 #define inode_gid(inode) ((inode).i_gid | (inode).osd2.linux2.l_i_gid_high << 16)
493 #define ext2fs_set_i_uid_high(inode,x) ((inode).osd2.linux2.l_i_uid_high = (x))
494 #define ext2fs_set_i_gid_high(inode,x) ((inode).osd2.linux2.l_i_gid_high = (x))
499 #define EXT2_VALID_FS 0x0001 /* Unmounted cleanly */
500 #define EXT2_ERROR_FS 0x0002 /* Errors detected */
501 #define EXT3_ORPHAN_FS 0x0004 /* Orphans being recovered */
504 * Misc. filesystem flags
506 #define EXT2_FLAGS_SIGNED_HASH 0x0001 /* Signed dirhash in use */
507 #define EXT2_FLAGS_UNSIGNED_HASH 0x0002 /* Unsigned dirhash in use */
508 #define EXT2_FLAGS_TEST_FILESYS 0x0004 /* OK for use on development code */
509 #define EXT2_FLAGS_IS_SNAPSHOT 0x0010 /* This is a snapshot image */
510 #define EXT2_FLAGS_FIX_SNAPSHOT 0x0020 /* Snapshot inodes corrupted */
511 #define EXT2_FLAGS_FIX_EXCLUDE 0x0040 /* Exclude bitmaps corrupted */
516 #define EXT2_MOUNT_CHECK 0x0001 /* Do mount-time checks */
517 #define EXT2_MOUNT_GRPID 0x0004 /* Create files with directory's group */
518 #define EXT2_MOUNT_DEBUG 0x0008 /* Some debugging messages */
519 #define EXT2_MOUNT_ERRORS_CONT 0x0010 /* Continue on errors */
520 #define EXT2_MOUNT_ERRORS_RO 0x0020 /* Remount fs ro on errors */
521 #define EXT2_MOUNT_ERRORS_PANIC 0x0040 /* Panic on errors */
522 #define EXT2_MOUNT_MINIX_DF 0x0080 /* Mimics the Minix statfs */
523 #define EXT2_MOUNT_NO_UID32 0x0200 /* Disable 32-bit UIDs */
525 #define clear_opt(o, opt) o &= ~EXT2_MOUNT_##opt
526 #define set_opt(o, opt) o |= EXT2_MOUNT_##opt
527 #define test_opt(sb, opt) (EXT2_SB(sb)->s_mount_opt & \
530 * Maximal mount counts between two filesystem checks
532 #define EXT2_DFL_MAX_MNT_COUNT 20 /* Allow 20 mounts */
533 #define EXT2_DFL_CHECKINTERVAL 0 /* Don't use interval check */
536 * Behaviour when detecting errors
538 #define EXT2_ERRORS_CONTINUE 1 /* Continue execution */
539 #define EXT2_ERRORS_RO 2 /* Remount fs read-only */
540 #define EXT2_ERRORS_PANIC 3 /* Panic */
541 #define EXT2_ERRORS_DEFAULT EXT2_ERRORS_CONTINUE
544 #define ext4_offsetof(TYPE,MEMBER) __builtin_offsetof(TYPE,MEMBER)
546 #define ext4_offsetof(TYPE, MEMBER) ((size_t) &((TYPE *)0)->MEMBER)
550 * Structure of the super block
552 struct ext2_super_block {
553 __u32 s_inodes_count; /* Inodes count */
554 __u32 s_blocks_count; /* Blocks count */
555 __u32 s_r_blocks_count; /* Reserved blocks count */
556 __u32 s_free_blocks_count; /* Free blocks count */
557 __u32 s_free_inodes_count; /* Free inodes count */
558 __u32 s_first_data_block; /* First Data Block */
559 __u32 s_log_block_size; /* Block size */
560 __u32 s_log_cluster_size; /* Allocation cluster size */
561 __u32 s_blocks_per_group; /* # Blocks per group */
562 __u32 s_clusters_per_group; /* # Fragments per group */
563 __u32 s_inodes_per_group; /* # Inodes per group */
564 __u32 s_mtime; /* Mount time */
565 __u32 s_wtime; /* Write time */
566 __u16 s_mnt_count; /* Mount count */
567 __s16 s_max_mnt_count; /* Maximal mount count */
568 __u16 s_magic; /* Magic signature */
569 __u16 s_state; /* File system state */
570 __u16 s_errors; /* Behaviour when detecting errors */
571 __u16 s_minor_rev_level; /* minor revision level */
572 __u32 s_lastcheck; /* time of last check */
573 __u32 s_checkinterval; /* max. time between checks */
574 __u32 s_creator_os; /* OS */
575 __u32 s_rev_level; /* Revision level */
576 __u16 s_def_resuid; /* Default uid for reserved blocks */
577 __u16 s_def_resgid; /* Default gid for reserved blocks */
579 * These fields are for EXT2_DYNAMIC_REV superblocks only.
581 * Note: the difference between the compatible feature set and
582 * the incompatible feature set is that if there is a bit set
583 * in the incompatible feature set that the kernel doesn't
584 * know about, it should refuse to mount the filesystem.
586 * e2fsck's requirements are more strict; if it doesn't know
587 * about a feature in either the compatible or incompatible
588 * feature set, it must abort and not try to meddle with
589 * things it doesn't understand...
591 __u32 s_first_ino; /* First non-reserved inode */
592 __u16 s_inode_size; /* size of inode structure */
593 __u16 s_block_group_nr; /* block group # of this superblock */
594 __u32 s_feature_compat; /* compatible feature set */
595 __u32 s_feature_incompat; /* incompatible feature set */
596 __u32 s_feature_ro_compat; /* readonly-compatible feature set */
597 __u8 s_uuid[16]; /* 128-bit uuid for volume */
598 char s_volume_name[16]; /* volume name */
599 char s_last_mounted[64]; /* directory where last mounted */
600 __u32 s_algorithm_usage_bitmap; /* For compression */
602 * Performance hints. Directory preallocation should only
603 * happen if the EXT2_FEATURE_COMPAT_DIR_PREALLOC flag is on.
605 __u8 s_prealloc_blocks; /* Nr of blocks to try to preallocate*/
606 __u8 s_prealloc_dir_blocks; /* Nr to preallocate for dirs */
607 __u16 s_reserved_gdt_blocks; /* Per group table for online growth */
609 * Journaling support valid if EXT2_FEATURE_COMPAT_HAS_JOURNAL set.
611 __u8 s_journal_uuid[16]; /* uuid of journal superblock */
612 __u32 s_journal_inum; /* inode number of journal file */
613 __u32 s_journal_dev; /* device number of journal file */
614 __u32 s_last_orphan; /* start of list of inodes to delete */
615 __u32 s_hash_seed[4]; /* HTREE hash seed */
616 __u8 s_def_hash_version; /* Default hash version to use */
617 __u8 s_jnl_backup_type; /* Default type of journal backup */
618 __u16 s_desc_size; /* Group desc. size: INCOMPAT_64BIT */
619 __u32 s_default_mount_opts;
620 __u32 s_first_meta_bg; /* First metablock group */
621 __u32 s_mkfs_time; /* When the filesystem was created */
622 __u32 s_jnl_blocks[17]; /* Backup of the journal inode */
623 __u32 s_blocks_count_hi; /* Blocks count high 32bits */
624 __u32 s_r_blocks_count_hi; /* Reserved blocks count high 32 bits*/
625 __u32 s_free_blocks_hi; /* Free blocks count */
626 __u16 s_min_extra_isize; /* All inodes have at least # bytes */
627 __u16 s_want_extra_isize; /* New inodes should reserve # bytes */
628 __u32 s_flags; /* Miscellaneous flags */
629 __u16 s_raid_stride; /* RAID stride */
630 __u16 s_mmp_update_interval; /* # seconds to wait in MMP checking */
631 __u64 s_mmp_block; /* Block for multi-mount protection */
632 __u32 s_raid_stripe_width; /* blocks on all data disks (N*stride)*/
633 __u8 s_log_groups_per_flex; /* FLEX_BG group size */
634 __u8 s_reserved_char_pad;
635 __u16 s_reserved_pad; /* Padding to next 32bits */
636 __u64 s_kbytes_written; /* nr of lifetime kilobytes written */
637 __u32 s_snapshot_inum; /* Inode number of active snapshot */
638 __u32 s_snapshot_id; /* sequential ID of active snapshot */
639 __u64 s_snapshot_r_blocks_count; /* reserved blocks for active
640 snapshot's future use */
641 __u32 s_snapshot_list; /* inode number of the head of the on-disk snapshot list */
642 #define EXT4_S_ERR_START ext4_offsetof(struct ext2_super_block, s_error_count)
643 __u32 s_error_count; /* number of fs errors */
644 __u32 s_first_error_time; /* first time an error happened */
645 __u32 s_first_error_ino; /* inode involved in first error */
646 __u64 s_first_error_block; /* block involved of first error */
647 __u8 s_first_error_func[32]; /* function where the error happened */
648 __u32 s_first_error_line; /* line number where error happened */
649 __u32 s_last_error_time; /* most recent time of an error */
650 __u32 s_last_error_ino; /* inode involved in last error */
651 __u32 s_last_error_line; /* line number where error happened */
652 __u64 s_last_error_block; /* block involved of last error */
653 __u8 s_last_error_func[32]; /* function where the error happened */
654 #define EXT4_S_ERR_END ext4_offsetof(struct ext2_super_block, s_mount_opts)
655 __u8 s_mount_opts[64];
656 __u32 s_usr_quota_inum; /* inode number of user quota file */
657 __u32 s_grp_quota_inum; /* inode number of group quota file */
658 __u32 s_overhead_blocks; /* overhead blocks/clusters in fs */
659 __u32 s_backup_bgs[2]; /* If sparse_super2 enabled */
660 __u32 s_reserved[106]; /* Padding to the end of the block */
661 __u32 s_checksum; /* crc32c(superblock) */
664 #define EXT4_S_ERR_LEN (EXT4_S_ERR_END - EXT4_S_ERR_START)
667 * Codes for operating systems
669 #define EXT2_OS_LINUX 0
670 #define EXT2_OS_HURD 1
671 #define EXT2_OBSO_OS_MASIX 2
672 #define EXT2_OS_FREEBSD 3
673 #define EXT2_OS_LITES 4
678 #define EXT2_GOOD_OLD_REV 0 /* The good old (original) format */
679 #define EXT2_DYNAMIC_REV 1 /* V2 format w/ dynamic inode sizes */
681 #define EXT2_CURRENT_REV EXT2_GOOD_OLD_REV
682 #define EXT2_MAX_SUPP_REV EXT2_DYNAMIC_REV
684 #define EXT2_GOOD_OLD_INODE_SIZE 128
687 * Journal inode backup types
689 #define EXT3_JNL_BACKUP_BLOCKS 1
692 * Feature set definitions
695 #define EXT2_HAS_COMPAT_FEATURE(sb,mask) \
696 ( EXT2_SB(sb)->s_feature_compat & (mask) )
697 #define EXT2_HAS_RO_COMPAT_FEATURE(sb,mask) \
698 ( EXT2_SB(sb)->s_feature_ro_compat & (mask) )
699 #define EXT2_HAS_INCOMPAT_FEATURE(sb,mask) \
700 ( EXT2_SB(sb)->s_feature_incompat & (mask) )
702 #define EXT2_FEATURE_COMPAT_DIR_PREALLOC 0x0001
703 #define EXT2_FEATURE_COMPAT_IMAGIC_INODES 0x0002
704 #define EXT3_FEATURE_COMPAT_HAS_JOURNAL 0x0004
705 #define EXT2_FEATURE_COMPAT_EXT_ATTR 0x0008
706 #define EXT2_FEATURE_COMPAT_RESIZE_INODE 0x0010
707 #define EXT2_FEATURE_COMPAT_DIR_INDEX 0x0020
708 #define EXT2_FEATURE_COMPAT_LAZY_BG 0x0040
709 /* #define EXT2_FEATURE_COMPAT_EXCLUDE_INODE 0x0080 not used, legacy */
710 #define EXT2_FEATURE_COMPAT_EXCLUDE_BITMAP 0x0100
711 #define EXT4_FEATURE_COMPAT_SPARSE_SUPER2 0x0200
714 #define EXT2_FEATURE_RO_COMPAT_SPARSE_SUPER 0x0001
715 #define EXT2_FEATURE_RO_COMPAT_LARGE_FILE 0x0002
716 /* #define EXT2_FEATURE_RO_COMPAT_BTREE_DIR 0x0004 not used */
717 #define EXT4_FEATURE_RO_COMPAT_HUGE_FILE 0x0008
718 #define EXT4_FEATURE_RO_COMPAT_GDT_CSUM 0x0010
719 #define EXT4_FEATURE_RO_COMPAT_DIR_NLINK 0x0020
720 #define EXT4_FEATURE_RO_COMPAT_EXTRA_ISIZE 0x0040
721 #define EXT4_FEATURE_RO_COMPAT_HAS_SNAPSHOT 0x0080
722 #define EXT4_FEATURE_RO_COMPAT_QUOTA 0x0100
723 #define EXT4_FEATURE_RO_COMPAT_BIGALLOC 0x0200
724 #define EXT4_FEATURE_RO_COMPAT_METADATA_CSUM 0x0400
725 #define EXT4_FEATURE_RO_COMPAT_REPLICA 0x0800
727 #define EXT2_FEATURE_INCOMPAT_COMPRESSION 0x0001
728 #define EXT2_FEATURE_INCOMPAT_FILETYPE 0x0002
729 #define EXT3_FEATURE_INCOMPAT_RECOVER 0x0004 /* Needs recovery */
730 #define EXT3_FEATURE_INCOMPAT_JOURNAL_DEV 0x0008 /* Journal device */
731 #define EXT2_FEATURE_INCOMPAT_META_BG 0x0010
732 #define EXT3_FEATURE_INCOMPAT_EXTENTS 0x0040
733 #define EXT4_FEATURE_INCOMPAT_64BIT 0x0080
734 #define EXT4_FEATURE_INCOMPAT_MMP 0x0100
735 #define EXT4_FEATURE_INCOMPAT_FLEX_BG 0x0200
736 #define EXT4_FEATURE_INCOMPAT_EA_INODE 0x0400
737 #define EXT4_FEATURE_INCOMPAT_DIRDATA 0x1000
738 /* 0x2000 was EXT4_FEATURE_INCOMPAT_BG_USE_META_CSUM but this was never used */
739 #define EXT4_FEATURE_INCOMPAT_LARGEDIR 0x4000 /* >2GB or 3-lvl htree */
740 #define EXT4_FEATURE_INCOMPAT_INLINEDATA 0x8000 /* data in inode */
742 #define EXT2_FEATURE_COMPAT_SUPP 0
743 #define EXT2_FEATURE_INCOMPAT_SUPP (EXT2_FEATURE_INCOMPAT_FILETYPE| \
744 EXT4_FEATURE_INCOMPAT_MMP| \
745 EXT4_FEATURE_INCOMPAT_EA_INODE)
746 #define EXT2_FEATURE_RO_COMPAT_SUPP (EXT2_FEATURE_RO_COMPAT_SPARSE_SUPER| \
747 EXT2_FEATURE_RO_COMPAT_LARGE_FILE| \
748 EXT4_FEATURE_RO_COMPAT_DIR_NLINK| \
749 EXT4_FEATURE_RO_COMPAT_EXTRA_ISIZE| \
750 EXT2_FEATURE_RO_COMPAT_BTREE_DIR)
753 * Default values for user and/or group using reserved blocks
755 #define EXT2_DEF_RESUID 0
756 #define EXT2_DEF_RESGID 0
759 * Default mount options
761 #define EXT2_DEFM_DEBUG 0x0001
762 #define EXT2_DEFM_BSDGROUPS 0x0002
763 #define EXT2_DEFM_XATTR_USER 0x0004
764 #define EXT2_DEFM_ACL 0x0008
765 #define EXT2_DEFM_UID16 0x0010
766 #define EXT3_DEFM_JMODE 0x0060
767 #define EXT3_DEFM_JMODE_DATA 0x0020
768 #define EXT3_DEFM_JMODE_ORDERED 0x0040
769 #define EXT3_DEFM_JMODE_WBACK 0x0060
770 #define EXT4_DEFM_NOBARRIER 0x0100
771 #define EXT4_DEFM_BLOCK_VALIDITY 0x0200
772 #define EXT4_DEFM_DISCARD 0x0400
773 #define EXT4_DEFM_NODELALLOC 0x0800
776 * Structure of a directory entry
778 #define EXT2_NAME_LEN 255
780 struct ext2_dir_entry {
781 __u32 inode; /* Inode number */
782 __u16 rec_len; /* Directory entry length */
783 __u16 name_len; /* Name length */
784 char name[EXT2_NAME_LEN]; /* File name */
788 * The new version of the directory entry. Since EXT2 structures are
789 * stored in intel byte order, and the name_len field could never be
790 * bigger than 255 chars, it's safe to reclaim the extra byte for the
793 struct ext2_dir_entry_2 {
794 __u32 inode; /* Inode number */
795 __u16 rec_len; /* Directory entry length */
796 __u8 name_len; /* Name length */
798 char name[EXT2_NAME_LEN]; /* File name */
802 * Ext2 directory file types. Only the low 3 bits are used. The
803 * other bits are reserved for now.
805 #define EXT2_FT_UNKNOWN 0
806 #define EXT2_FT_REG_FILE 1
807 #define EXT2_FT_DIR 2
808 #define EXT2_FT_CHRDEV 3
809 #define EXT2_FT_BLKDEV 4
810 #define EXT2_FT_FIFO 5
811 #define EXT2_FT_SOCK 6
812 #define EXT2_FT_SYMLINK 7
814 #define EXT2_FT_MAX 8
817 * EXT2_DIR_PAD defines the directory entries boundaries
819 * NOTE: It must be a multiple of 4
821 #define EXT2_DIR_PAD 4
822 #define EXT2_DIR_ROUND (EXT2_DIR_PAD - 1)
823 #define EXT2_DIR_REC_LEN(name_len) (((name_len) + 8 + EXT2_DIR_ROUND) & \
827 * This structure is used for multiple mount protection. It is written
828 * into the block number saved in the s_mmp_block field in the superblock.
829 * Programs that check MMP should assume that if SEQ_FSCK (or any unknown
830 * code above SEQ_MAX) is present then it is NOT safe to use the filesystem,
831 * regardless of how old the timestamp is.
833 * The timestamp in the MMP structure will be updated by e2fsck at some
834 * arbitary intervals (start of passes, after every few groups of inodes
835 * in pass1 and pass1b). There is no guarantee that e2fsck is updating
836 * the MMP block in a timely manner, and the updates it does are purely
837 * for the convenience of the sysadmin and not for automatic validation.
839 * Note: Only the mmp_seq value is used to determine whether the MMP block
840 * is being updated. The mmp_time, mmp_nodename, and mmp_bdevname
841 * fields are only for informational purposes for the administrator,
842 * due to clock skew between nodes and hostname HA service takeover.
844 #define EXT4_MMP_MAGIC 0x004D4D50U /* ASCII for MMP */
845 #define EXT4_MMP_SEQ_CLEAN 0xFF4D4D50U /* mmp_seq value for clean unmount */
846 #define EXT4_MMP_SEQ_FSCK 0xE24D4D50U /* mmp_seq value when being fscked */
847 #define EXT4_MMP_SEQ_MAX 0xE24D4D4FU /* maximum valid mmp_seq value */
850 __u32 mmp_magic; /* Magic number for MMP */
851 __u32 mmp_seq; /* Sequence no. updated periodically */
852 __u64 mmp_time; /* Time last updated */
853 char mmp_nodename[64]; /* Node which last updated MMP block */
854 char mmp_bdevname[32]; /* Bdev which last updated MMP block */
855 __u16 mmp_check_interval; /* Changed mmp_check_interval */
861 * Default interval for MMP update in seconds.
863 #define EXT4_MMP_UPDATE_INTERVAL 5
866 * Maximum interval for MMP update in seconds.
868 #define EXT4_MMP_MAX_UPDATE_INTERVAL 300
871 * Minimum interval for MMP checking in seconds.
873 #define EXT4_MMP_MIN_CHECK_INTERVAL 5
875 #endif /* _LINUX_EXT2_FS_H */