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 EXT4_BG_INODE_BITMAP_CSUM_HI_END \
196 (offsetof(struct ext4_group_desc, bg_inode_bitmap_csum_hi) + \
198 #define EXT4_BG_BLOCK_BITMAP_CSUM_HI_LOCATION \
199 (offsetof(struct ext4_group_desc, bg_block_bitmap_csum_hi) + \
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 */
207 * Data structures used by the directory indexing feature
209 * Note: all of the multibyte integer fields are little endian.
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.
218 struct ext2_dx_root_info
{
220 __u8 hash_version
; /* 0 now, 1 at release */
221 __u8 info_length
; /* 8 */
222 __u8 indirect_levels
;
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 */
233 #define EXT2_HASH_FLAG_INCOMPAT 0x1
235 struct ext2_dx_entry
{
240 struct ext2_dx_countlimit
{
246 * This goes at the end of each htree block.
248 struct ext2_dx_tail
{
250 __le32 dt_checksum
; /* crc32c(uuid+inum+dxblock) */
254 * Macro-instructions used to manage group descriptors
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)
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) / \
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))
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)
278 #define EXT2_DESC_PER_BLOCK(s) (EXT2_BLOCK_SIZE(s) / EXT2_DESC_SIZE(s))
281 #define EXT2_GROUPS_TO_BLOCKS(s, g) ((blk64_t) EXT2_BLOCKS_PER_GROUP(s) * \
283 #define EXT2_GROUPS_TO_CLUSTERS(s, g) ((blk64_t) EXT2_CLUSTERS_PER_GROUP(s) * \
287 * Constants relative to the data blocks
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)
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 */
332 #define EXT2_FL_USER_VISIBLE 0x204BDFFF /* User visible flags */
333 #define EXT2_FL_USER_MODIFIABLE 0x204B80FF /* User modifiable flags */
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 */
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 */
360 #ifdef __GNU__ /* Needed for the Hurd */
361 #define _IOT_ext2_new_group_input _IOT (_IOTS(__u32), 5, _IOTS(__u16), 2, 0, 0)
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)
376 * Structure of an inode on the disk
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 */
392 __u32 l_i_version
; /* was l_i_reserved1 */
395 __u32 h_i_translator
;
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 */
402 __u32 i_faddr
; /* Fragment address */
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) */
413 __u8 h_i_frag
; /* Fragment number */
414 __u8 h_i_fsize
; /* Fragment size */
420 } osd2
; /* OS dependent 2 */
424 * Permanent part of an large inode on the disk
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 */
440 __u32 l_i_version
; /* was l_i_reserved1 */
443 __u32 h_i_translator
;
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 */
450 __u32 i_faddr
; /* Fragment address */
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) */
461 __u8 h_i_frag
; /* Fragment number */
462 __u8 h_i_fsize
; /* Fragment size */
468 } osd2
; /* OS dependent 2 */
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 */
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)
484 #define EXT4_EPOCH_BITS 2
485 #define EXT4_EPOCH_MASK ((1 << EXT4_EPOCH_BITS) - 1)
487 #define i_checksum_lo osd2.linux2.l_i_checksum_lo
489 #define inode_includes(size, field) \
490 (size >= (sizeof(((struct ext2_inode_large *)0)->field) + \
491 offsetof(struct ext2_inode_large, field)))
493 #if defined(__KERNEL__) || defined(__linux__)
494 #define i_reserved1 osd1.linux1.l_i_reserved1
495 #define i_frag osd2.linux2.l_i_frag
496 #define i_fsize osd2.linux2.l_i_fsize
497 #define i_uid_low i_uid
498 #define i_gid_low i_gid
499 #define i_uid_high osd2.linux2.l_i_uid_high
500 #define i_gid_high osd2.linux2.l_i_gid_high
504 #define i_translator osd1.hurd1.h_i_translator
505 #define i_frag osd2.hurd2.h_i_frag;
506 #define i_fsize osd2.hurd2.h_i_fsize;
507 #define i_uid_high osd2.hurd2.h_i_uid_high
508 #define i_gid_high osd2.hurd2.h_i_gid_high
509 #define i_author osd2.hurd2.h_i_author
512 #endif /* defined(__KERNEL__) || defined(__linux__) */
514 #define inode_uid(inode) ((inode).i_uid | (inode).osd2.linux2.l_i_uid_high << 16)
515 #define inode_gid(inode) ((inode).i_gid | (inode).osd2.linux2.l_i_gid_high << 16)
516 #define inode_projid(inode) ((inode).i_projid)
517 #define ext2fs_set_i_uid_high(inode,x) ((inode).osd2.linux2.l_i_uid_high = (x))
518 #define ext2fs_set_i_gid_high(inode,x) ((inode).osd2.linux2.l_i_gid_high = (x))
521 struct ext2_inode
*EXT2_INODE(struct ext2_inode_large
*large_inode
)
523 return (struct ext2_inode
*) large_inode
;
529 #define EXT2_VALID_FS 0x0001 /* Unmounted cleanly */
530 #define EXT2_ERROR_FS 0x0002 /* Errors detected */
531 #define EXT3_ORPHAN_FS 0x0004 /* Orphans being recovered */
534 * Misc. filesystem flags
536 #define EXT2_FLAGS_SIGNED_HASH 0x0001 /* Signed dirhash in use */
537 #define EXT2_FLAGS_UNSIGNED_HASH 0x0002 /* Unsigned dirhash in use */
538 #define EXT2_FLAGS_TEST_FILESYS 0x0004 /* OK for use on development code */
539 #define EXT2_FLAGS_IS_SNAPSHOT 0x0010 /* This is a snapshot image */
540 #define EXT2_FLAGS_FIX_SNAPSHOT 0x0020 /* Snapshot inodes corrupted */
541 #define EXT2_FLAGS_FIX_EXCLUDE 0x0040 /* Exclude bitmaps corrupted */
546 #define EXT2_MOUNT_CHECK 0x0001 /* Do mount-time checks */
547 #define EXT2_MOUNT_GRPID 0x0004 /* Create files with directory's group */
548 #define EXT2_MOUNT_DEBUG 0x0008 /* Some debugging messages */
549 #define EXT2_MOUNT_ERRORS_CONT 0x0010 /* Continue on errors */
550 #define EXT2_MOUNT_ERRORS_RO 0x0020 /* Remount fs ro on errors */
551 #define EXT2_MOUNT_ERRORS_PANIC 0x0040 /* Panic on errors */
552 #define EXT2_MOUNT_MINIX_DF 0x0080 /* Mimics the Minix statfs */
553 #define EXT2_MOUNT_NO_UID32 0x0200 /* Disable 32-bit UIDs */
555 #define clear_opt(o, opt) o &= ~EXT2_MOUNT_##opt
556 #define set_opt(o, opt) o |= EXT2_MOUNT_##opt
557 #define test_opt(sb, opt) (EXT2_SB(sb)->s_mount_opt & \
560 * Maximal mount counts between two filesystem checks
562 #define EXT2_DFL_MAX_MNT_COUNT 20 /* Allow 20 mounts */
563 #define EXT2_DFL_CHECKINTERVAL 0 /* Don't use interval check */
566 * Behaviour when detecting errors
568 #define EXT2_ERRORS_CONTINUE 1 /* Continue execution */
569 #define EXT2_ERRORS_RO 2 /* Remount fs read-only */
570 #define EXT2_ERRORS_PANIC 3 /* Panic */
571 #define EXT2_ERRORS_DEFAULT EXT2_ERRORS_CONTINUE
574 #define ext4_offsetof(TYPE,MEMBER) __builtin_offsetof(TYPE,MEMBER)
576 #define ext4_offsetof(TYPE, MEMBER) ((size_t) &((TYPE *)0)->MEMBER)
579 /* Metadata checksum algorithms */
580 #define EXT2_CRC32C_CHKSUM 1
582 /* Encryption algorithms, key size and key reference len */
583 #define EXT4_ENCRYPTION_MODE_INVALID 0
584 #define EXT4_ENCRYPTION_MODE_AES_256_XTS 1
585 #define EXT4_ENCRYPTION_MODE_AES_256_GCM 2
586 #define EXT4_ENCRYPTION_MODE_AES_256_CBC 3
587 #define EXT4_ENCRYPTION_MODE_AES_256_CTS 4
589 #define EXT4_AES_256_XTS_KEY_SIZE 64
590 #define EXT4_AES_256_GCM_KEY_SIZE 32
591 #define EXT4_AES_256_CBC_KEY_SIZE 32
592 #define EXT4_AES_256_CTS_KEY_SIZE 32
593 #define EXT4_MAX_KEY_SIZE 64
595 #define EXT4_KEY_DESCRIPTOR_SIZE 8
596 #define EXT4_CRYPTO_BLOCK_SIZE 16
598 /* Password derivation constants */
599 #define EXT4_MAX_PASSPHRASE_SIZE 1024
600 #define EXT4_MAX_SALT_SIZE 256
601 #define EXT4_PBKDF2_ITERATIONS 0xFFFF
603 #define EXT2_LABEL_LEN 16
606 * Policy provided via an ioctl on the topmost directory. This
607 * structure is also in the kernel.
609 struct ext4_encryption_policy
{
611 char contents_encryption_mode
;
612 char filenames_encryption_mode
;
614 char master_key_descriptor
[EXT4_KEY_DESCRIPTOR_SIZE
];
615 } __attribute__((__packed__
));
617 struct ext4_encryption_key
{
619 char raw
[EXT4_MAX_KEY_SIZE
];
621 } __attribute__((__packed__
));
624 * Structure of the super block
626 struct ext2_super_block
{
627 __u32 s_inodes_count
; /* Inodes count */
628 __u32 s_blocks_count
; /* Blocks count */
629 __u32 s_r_blocks_count
; /* Reserved blocks count */
630 __u32 s_free_blocks_count
; /* Free blocks count */
631 __u32 s_free_inodes_count
; /* Free inodes count */
632 __u32 s_first_data_block
; /* First Data Block */
633 __u32 s_log_block_size
; /* Block size */
634 __u32 s_log_cluster_size
; /* Allocation cluster size */
635 __u32 s_blocks_per_group
; /* # Blocks per group */
636 __u32 s_clusters_per_group
; /* # Fragments per group */
637 __u32 s_inodes_per_group
; /* # Inodes per group */
638 __u32 s_mtime
; /* Mount time */
639 __u32 s_wtime
; /* Write time */
640 __u16 s_mnt_count
; /* Mount count */
641 __s16 s_max_mnt_count
; /* Maximal mount count */
642 __u16 s_magic
; /* Magic signature */
643 __u16 s_state
; /* File system state */
644 __u16 s_errors
; /* Behaviour when detecting errors */
645 __u16 s_minor_rev_level
; /* minor revision level */
646 __u32 s_lastcheck
; /* time of last check */
647 __u32 s_checkinterval
; /* max. time between checks */
648 __u32 s_creator_os
; /* OS */
649 __u32 s_rev_level
; /* Revision level */
650 __u16 s_def_resuid
; /* Default uid for reserved blocks */
651 __u16 s_def_resgid
; /* Default gid for reserved blocks */
653 * These fields are for EXT2_DYNAMIC_REV superblocks only.
655 * Note: the difference between the compatible feature set and
656 * the incompatible feature set is that if there is a bit set
657 * in the incompatible feature set that the kernel doesn't
658 * know about, it should refuse to mount the filesystem.
660 * e2fsck's requirements are more strict; if it doesn't know
661 * about a feature in either the compatible or incompatible
662 * feature set, it must abort and not try to meddle with
663 * things it doesn't understand...
665 __u32 s_first_ino
; /* First non-reserved inode */
666 __u16 s_inode_size
; /* size of inode structure */
667 __u16 s_block_group_nr
; /* block group # of this superblock */
668 __u32 s_feature_compat
; /* compatible feature set */
669 __u32 s_feature_incompat
; /* incompatible feature set */
670 __u32 s_feature_ro_compat
; /* readonly-compatible feature set */
671 __u8 s_uuid
[16]; /* 128-bit uuid for volume */
672 char s_volume_name
[EXT2_LABEL_LEN
]; /* volume name */
673 char s_last_mounted
[64]; /* directory where last mounted */
674 __u32 s_algorithm_usage_bitmap
; /* For compression */
676 * Performance hints. Directory preallocation should only
677 * happen if the EXT2_FEATURE_COMPAT_DIR_PREALLOC flag is on.
679 __u8 s_prealloc_blocks
; /* Nr of blocks to try to preallocate*/
680 __u8 s_prealloc_dir_blocks
; /* Nr to preallocate for dirs */
681 __u16 s_reserved_gdt_blocks
; /* Per group table for online growth */
683 * Journaling support valid if EXT2_FEATURE_COMPAT_HAS_JOURNAL set.
685 __u8 s_journal_uuid
[16]; /* uuid of journal superblock */
686 __u32 s_journal_inum
; /* inode number of journal file */
687 __u32 s_journal_dev
; /* device number of journal file */
688 __u32 s_last_orphan
; /* start of list of inodes to delete */
689 __u32 s_hash_seed
[4]; /* HTREE hash seed */
690 __u8 s_def_hash_version
; /* Default hash version to use */
691 __u8 s_jnl_backup_type
; /* Default type of journal backup */
692 __u16 s_desc_size
; /* Group desc. size: INCOMPAT_64BIT */
693 __u32 s_default_mount_opts
;
694 __u32 s_first_meta_bg
; /* First metablock group */
695 __u32 s_mkfs_time
; /* When the filesystem was created */
696 __u32 s_jnl_blocks
[17]; /* Backup of the journal inode */
697 __u32 s_blocks_count_hi
; /* Blocks count high 32bits */
698 __u32 s_r_blocks_count_hi
; /* Reserved blocks count high 32 bits*/
699 __u32 s_free_blocks_hi
; /* Free blocks count */
700 __u16 s_min_extra_isize
; /* All inodes have at least # bytes */
701 __u16 s_want_extra_isize
; /* New inodes should reserve # bytes */
702 __u32 s_flags
; /* Miscellaneous flags */
703 __u16 s_raid_stride
; /* RAID stride */
704 __u16 s_mmp_update_interval
; /* # seconds to wait in MMP checking */
705 __u64 s_mmp_block
; /* Block for multi-mount protection */
706 __u32 s_raid_stripe_width
; /* blocks on all data disks (N*stride)*/
707 __u8 s_log_groups_per_flex
; /* FLEX_BG group size */
708 __u8 s_checksum_type
; /* metadata checksum algorithm */
709 __u8 s_encryption_level
; /* versioning level for encryption */
710 __u8 s_reserved_pad
; /* Padding to next 32bits */
711 __u64 s_kbytes_written
; /* nr of lifetime kilobytes written */
712 __u32 s_snapshot_inum
; /* Inode number of active snapshot */
713 __u32 s_snapshot_id
; /* sequential ID of active snapshot */
714 __u64 s_snapshot_r_blocks_count
; /* reserved blocks for active
715 snapshot's future use */
716 __u32 s_snapshot_list
; /* inode number of the head of the on-disk snapshot list */
717 #define EXT4_S_ERR_START ext4_offsetof(struct ext2_super_block, s_error_count)
718 __u32 s_error_count
; /* number of fs errors */
719 __u32 s_first_error_time
; /* first time an error happened */
720 __u32 s_first_error_ino
; /* inode involved in first error */
721 __u64 s_first_error_block
; /* block involved of first error */
722 __u8 s_first_error_func
[32]; /* function where the error happened */
723 __u32 s_first_error_line
; /* line number where error happened */
724 __u32 s_last_error_time
; /* most recent time of an error */
725 __u32 s_last_error_ino
; /* inode involved in last error */
726 __u32 s_last_error_line
; /* line number where error happened */
727 __u64 s_last_error_block
; /* block involved of last error */
728 __u8 s_last_error_func
[32]; /* function where the error happened */
729 #define EXT4_S_ERR_END ext4_offsetof(struct ext2_super_block, s_mount_opts)
730 __u8 s_mount_opts
[64];
731 __u32 s_usr_quota_inum
; /* inode number of user quota file */
732 __u32 s_grp_quota_inum
; /* inode number of group quota file */
733 __u32 s_overhead_blocks
; /* overhead blocks/clusters in fs */
734 __u32 s_backup_bgs
[2]; /* If sparse_super2 enabled */
735 __u8 s_encrypt_algos
[4]; /* Encryption algorithms in use */
736 __u8 s_encrypt_pw_salt
[16]; /* Salt used for string2key algorithm */
737 __le32 s_lpf_ino
; /* Location of the lost+found inode */
738 __le32 s_prj_quota_inum
; /* inode for tracking project quota */
739 __le32 s_checksum_seed
; /* crc32c(orig_uuid) if csum_seed set */
740 __le32 s_reserved
[98]; /* Padding to the end of the block */
741 __u32 s_checksum
; /* crc32c(superblock) */
744 #define EXT4_S_ERR_LEN (EXT4_S_ERR_END - EXT4_S_ERR_START)
747 * Codes for operating systems
749 #define EXT2_OS_LINUX 0
750 #define EXT2_OS_HURD 1
751 #define EXT2_OBSO_OS_MASIX 2
752 #define EXT2_OS_FREEBSD 3
753 #define EXT2_OS_LITES 4
758 #define EXT2_GOOD_OLD_REV 0 /* The good old (original) format */
759 #define EXT2_DYNAMIC_REV 1 /* V2 format w/ dynamic inode sizes */
761 #define EXT2_CURRENT_REV EXT2_GOOD_OLD_REV
762 #define EXT2_MAX_SUPP_REV EXT2_DYNAMIC_REV
764 #define EXT2_GOOD_OLD_INODE_SIZE 128
767 * Journal inode backup types
769 #define EXT3_JNL_BACKUP_BLOCKS 1
772 * Feature set definitions
775 #define EXT2_HAS_COMPAT_FEATURE(sb,mask) \
776 ( EXT2_SB(sb)->s_feature_compat & (mask) )
777 #define EXT2_HAS_RO_COMPAT_FEATURE(sb,mask) \
778 ( EXT2_SB(sb)->s_feature_ro_compat & (mask) )
779 #define EXT2_HAS_INCOMPAT_FEATURE(sb,mask) \
780 ( EXT2_SB(sb)->s_feature_incompat & (mask) )
782 #define EXT2_FEATURE_COMPAT_DIR_PREALLOC 0x0001
783 #define EXT2_FEATURE_COMPAT_IMAGIC_INODES 0x0002
784 #define EXT3_FEATURE_COMPAT_HAS_JOURNAL 0x0004
785 #define EXT2_FEATURE_COMPAT_EXT_ATTR 0x0008
786 #define EXT2_FEATURE_COMPAT_RESIZE_INODE 0x0010
787 #define EXT2_FEATURE_COMPAT_DIR_INDEX 0x0020
788 #define EXT2_FEATURE_COMPAT_LAZY_BG 0x0040
789 /* #define EXT2_FEATURE_COMPAT_EXCLUDE_INODE 0x0080 not used, legacy */
790 #define EXT2_FEATURE_COMPAT_EXCLUDE_BITMAP 0x0100
791 #define EXT4_FEATURE_COMPAT_SPARSE_SUPER2 0x0200
794 #define EXT2_FEATURE_RO_COMPAT_SPARSE_SUPER 0x0001
795 #define EXT2_FEATURE_RO_COMPAT_LARGE_FILE 0x0002
796 /* #define EXT2_FEATURE_RO_COMPAT_BTREE_DIR 0x0004 not used */
797 #define EXT4_FEATURE_RO_COMPAT_HUGE_FILE 0x0008
798 #define EXT4_FEATURE_RO_COMPAT_GDT_CSUM 0x0010
799 #define EXT4_FEATURE_RO_COMPAT_DIR_NLINK 0x0020
800 #define EXT4_FEATURE_RO_COMPAT_EXTRA_ISIZE 0x0040
801 #define EXT4_FEATURE_RO_COMPAT_HAS_SNAPSHOT 0x0080
802 #define EXT4_FEATURE_RO_COMPAT_QUOTA 0x0100
803 #define EXT4_FEATURE_RO_COMPAT_BIGALLOC 0x0200
805 * METADATA_CSUM implies GDT_CSUM. When METADATA_CSUM is set, group
806 * descriptor checksums use the same algorithm as all other data
807 * structures' checksums.
809 #define EXT4_FEATURE_RO_COMPAT_METADATA_CSUM 0x0400
810 #define EXT4_FEATURE_RO_COMPAT_REPLICA 0x0800
811 #define EXT4_FEATURE_RO_COMPAT_READONLY 0x1000
812 #define EXT4_FEATURE_RO_COMPAT_PROJECT 0x2000 /* Project quota */
815 #define EXT2_FEATURE_INCOMPAT_COMPRESSION 0x0001
816 #define EXT2_FEATURE_INCOMPAT_FILETYPE 0x0002
817 #define EXT3_FEATURE_INCOMPAT_RECOVER 0x0004 /* Needs recovery */
818 #define EXT3_FEATURE_INCOMPAT_JOURNAL_DEV 0x0008 /* Journal device */
819 #define EXT2_FEATURE_INCOMPAT_META_BG 0x0010
820 #define EXT3_FEATURE_INCOMPAT_EXTENTS 0x0040
821 #define EXT4_FEATURE_INCOMPAT_64BIT 0x0080
822 #define EXT4_FEATURE_INCOMPAT_MMP 0x0100
823 #define EXT4_FEATURE_INCOMPAT_FLEX_BG 0x0200
824 #define EXT4_FEATURE_INCOMPAT_EA_INODE 0x0400
825 #define EXT4_FEATURE_INCOMPAT_DIRDATA 0x1000
826 #define EXT4_FEATURE_INCOMPAT_CSUM_SEED 0x2000
827 #define EXT4_FEATURE_INCOMPAT_LARGEDIR 0x4000 /* >2GB or 3-lvl htree */
828 #define EXT4_FEATURE_INCOMPAT_INLINE_DATA 0x8000 /* data in inode */
829 #define EXT4_FEATURE_INCOMPAT_ENCRYPT 0x10000
831 #define EXT4_FEATURE_COMPAT_FUNCS(name, ver, flagname) \
832 static inline int ext2fs_has_feature_##name(struct ext2_super_block *sb) \
834 return ((EXT2_SB(sb)->s_feature_compat & \
835 EXT##ver##_FEATURE_COMPAT_##flagname) != 0); \
837 static inline void ext2fs_set_feature_##name(struct ext2_super_block *sb) \
839 EXT2_SB(sb)->s_feature_compat |= \
840 EXT##ver##_FEATURE_COMPAT_##flagname; \
842 static inline void ext2fs_clear_feature_##name(struct ext2_super_block *sb) \
844 EXT2_SB(sb)->s_feature_compat &= \
845 ~EXT##ver##_FEATURE_COMPAT_##flagname; \
848 #define EXT4_FEATURE_RO_COMPAT_FUNCS(name, ver, flagname) \
849 static inline int ext2fs_has_feature_##name(struct ext2_super_block *sb) \
851 return ((EXT2_SB(sb)->s_feature_ro_compat & \
852 EXT##ver##_FEATURE_RO_COMPAT_##flagname) != 0); \
854 static inline void ext2fs_set_feature_##name(struct ext2_super_block *sb) \
856 EXT2_SB(sb)->s_feature_ro_compat |= \
857 EXT##ver##_FEATURE_RO_COMPAT_##flagname; \
859 static inline void ext2fs_clear_feature_##name(struct ext2_super_block *sb) \
861 EXT2_SB(sb)->s_feature_ro_compat &= \
862 ~EXT##ver##_FEATURE_RO_COMPAT_##flagname; \
865 #define EXT4_FEATURE_INCOMPAT_FUNCS(name, ver, flagname) \
866 static inline int ext2fs_has_feature_##name(struct ext2_super_block *sb) \
868 return ((EXT2_SB(sb)->s_feature_incompat & \
869 EXT##ver##_FEATURE_INCOMPAT_##flagname) != 0); \
871 static inline void ext2fs_set_feature_##name(struct ext2_super_block *sb) \
873 EXT2_SB(sb)->s_feature_incompat |= \
874 EXT##ver##_FEATURE_INCOMPAT_##flagname; \
876 static inline void ext2fs_clear_feature_##name(struct ext2_super_block *sb) \
878 EXT2_SB(sb)->s_feature_incompat &= \
879 ~EXT##ver##_FEATURE_INCOMPAT_##flagname; \
882 EXT4_FEATURE_COMPAT_FUNCS(dir_prealloc
, 2, DIR_PREALLOC
)
883 EXT4_FEATURE_COMPAT_FUNCS(imagic_inodes
, 2, IMAGIC_INODES
)
884 EXT4_FEATURE_COMPAT_FUNCS(journal
, 3, HAS_JOURNAL
)
885 EXT4_FEATURE_COMPAT_FUNCS(xattr
, 2, EXT_ATTR
)
886 EXT4_FEATURE_COMPAT_FUNCS(resize_inode
, 2, RESIZE_INODE
)
887 EXT4_FEATURE_COMPAT_FUNCS(dir_index
, 2, DIR_INDEX
)
888 EXT4_FEATURE_COMPAT_FUNCS(lazy_bg
, 2, LAZY_BG
)
889 EXT4_FEATURE_COMPAT_FUNCS(exclude_bitmap
, 2, EXCLUDE_BITMAP
)
890 EXT4_FEATURE_COMPAT_FUNCS(sparse_super2
, 4, SPARSE_SUPER2
)
892 EXT4_FEATURE_RO_COMPAT_FUNCS(sparse_super
, 2, SPARSE_SUPER
)
893 EXT4_FEATURE_RO_COMPAT_FUNCS(large_file
, 2, LARGE_FILE
)
894 EXT4_FEATURE_RO_COMPAT_FUNCS(huge_file
, 4, HUGE_FILE
)
895 EXT4_FEATURE_RO_COMPAT_FUNCS(gdt_csum
, 4, GDT_CSUM
)
896 EXT4_FEATURE_RO_COMPAT_FUNCS(dir_nlink
, 4, DIR_NLINK
)
897 EXT4_FEATURE_RO_COMPAT_FUNCS(extra_isize
, 4, EXTRA_ISIZE
)
898 EXT4_FEATURE_RO_COMPAT_FUNCS(has_snapshot
, 4, HAS_SNAPSHOT
)
899 EXT4_FEATURE_RO_COMPAT_FUNCS(quota
, 4, QUOTA
)
900 EXT4_FEATURE_RO_COMPAT_FUNCS(bigalloc
, 4, BIGALLOC
)
901 EXT4_FEATURE_RO_COMPAT_FUNCS(metadata_csum
, 4, METADATA_CSUM
)
902 EXT4_FEATURE_RO_COMPAT_FUNCS(replica
, 4, REPLICA
)
903 EXT4_FEATURE_RO_COMPAT_FUNCS(readonly
, 4, READONLY
)
904 EXT4_FEATURE_RO_COMPAT_FUNCS(project
, 4, PROJECT
)
906 EXT4_FEATURE_INCOMPAT_FUNCS(compression
, 2, COMPRESSION
)
907 EXT4_FEATURE_INCOMPAT_FUNCS(filetype
, 2, FILETYPE
)
908 EXT4_FEATURE_INCOMPAT_FUNCS(journal_needs_recovery
, 3, RECOVER
)
909 EXT4_FEATURE_INCOMPAT_FUNCS(journal_dev
, 3, JOURNAL_DEV
)
910 EXT4_FEATURE_INCOMPAT_FUNCS(meta_bg
, 2, META_BG
)
911 EXT4_FEATURE_INCOMPAT_FUNCS(extents
, 3, EXTENTS
)
912 EXT4_FEATURE_INCOMPAT_FUNCS(64bit
, 4, 64BIT
)
913 EXT4_FEATURE_INCOMPAT_FUNCS(mmp
, 4, MMP
)
914 EXT4_FEATURE_INCOMPAT_FUNCS(flex_bg
, 4, FLEX_BG
)
915 EXT4_FEATURE_INCOMPAT_FUNCS(ea_inode
, 4, EA_INODE
)
916 EXT4_FEATURE_INCOMPAT_FUNCS(dirdata
, 4, DIRDATA
)
917 EXT4_FEATURE_INCOMPAT_FUNCS(csum_seed
, 4, CSUM_SEED
)
918 EXT4_FEATURE_INCOMPAT_FUNCS(largedir
, 4, LARGEDIR
)
919 EXT4_FEATURE_INCOMPAT_FUNCS(inline_data
, 4, INLINE_DATA
)
920 EXT4_FEATURE_INCOMPAT_FUNCS(encrypt
, 4, ENCRYPT
)
922 #define EXT2_FEATURE_COMPAT_SUPP 0
923 #define EXT2_FEATURE_INCOMPAT_SUPP (EXT2_FEATURE_INCOMPAT_FILETYPE| \
924 EXT4_FEATURE_INCOMPAT_MMP| \
925 EXT4_FEATURE_INCOMPAT_LARGEDIR)
926 #define EXT2_FEATURE_RO_COMPAT_SUPP (EXT2_FEATURE_RO_COMPAT_SPARSE_SUPER| \
927 EXT2_FEATURE_RO_COMPAT_LARGE_FILE| \
928 EXT4_FEATURE_RO_COMPAT_DIR_NLINK| \
929 EXT2_FEATURE_RO_COMPAT_BTREE_DIR)
932 * Default values for user and/or group using reserved blocks
934 #define EXT2_DEF_RESUID 0
935 #define EXT2_DEF_RESGID 0
938 * Default mount options
940 #define EXT2_DEFM_DEBUG 0x0001
941 #define EXT2_DEFM_BSDGROUPS 0x0002
942 #define EXT2_DEFM_XATTR_USER 0x0004
943 #define EXT2_DEFM_ACL 0x0008
944 #define EXT2_DEFM_UID16 0x0010
945 #define EXT3_DEFM_JMODE 0x0060
946 #define EXT3_DEFM_JMODE_DATA 0x0020
947 #define EXT3_DEFM_JMODE_ORDERED 0x0040
948 #define EXT3_DEFM_JMODE_WBACK 0x0060
949 #define EXT4_DEFM_NOBARRIER 0x0100
950 #define EXT4_DEFM_BLOCK_VALIDITY 0x0200
951 #define EXT4_DEFM_DISCARD 0x0400
952 #define EXT4_DEFM_NODELALLOC 0x0800
955 * Structure of a directory entry
957 #define EXT2_NAME_LEN 255
959 struct ext2_dir_entry
{
960 __u32 inode
; /* Inode number */
961 __u16 rec_len
; /* Directory entry length */
962 __u16 name_len
; /* Name length */
963 char name
[EXT2_NAME_LEN
]; /* File name */
967 * The new version of the directory entry. Since EXT2 structures are
968 * stored in intel byte order, and the name_len field could never be
969 * bigger than 255 chars, it's safe to reclaim the extra byte for the
972 * This structure is deprecated due to endianity issues. Please use struct
973 * ext2_dir_entry and accessor functions
974 * ext2fs_dirent_name_len
975 * ext2fs_dirent_set_name_len
976 * ext2fs_dirent_file_type
977 * ext2fs_dirent_set_file_type
978 * to get and set name_len and file_type fields.
980 struct ext2_dir_entry_2
{
981 __u32 inode
; /* Inode number */
982 __u16 rec_len
; /* Directory entry length */
983 __u8 name_len
; /* Name length */
985 char name
[EXT2_NAME_LEN
]; /* File name */
989 * This is a bogus directory entry at the end of each leaf block that
992 struct ext2_dir_entry_tail
{
993 __u32 det_reserved_zero1
; /* Pretend to be unused */
994 __u16 det_rec_len
; /* 12 */
995 __u16 det_reserved_name_len
; /* 0xDE00, fake namelen/filetype */
996 __u32 det_checksum
; /* crc32c(uuid+inode+dirent) */
1000 * Ext2 directory file types. Only the low 3 bits are used. The
1001 * other bits are reserved for now.
1003 #define EXT2_FT_UNKNOWN 0
1004 #define EXT2_FT_REG_FILE 1
1005 #define EXT2_FT_DIR 2
1006 #define EXT2_FT_CHRDEV 3
1007 #define EXT2_FT_BLKDEV 4
1008 #define EXT2_FT_FIFO 5
1009 #define EXT2_FT_SOCK 6
1010 #define EXT2_FT_SYMLINK 7
1012 #define EXT2_FT_MAX 8
1015 * Annoyingly, e2fsprogs always swab16s ext2_dir_entry.name_len, so we
1016 * have to build ext2_dir_entry_tail with that assumption too. This
1017 * constant helps to build the dir_entry_tail to look like it has an
1018 * "invalid" file type.
1020 #define EXT2_DIR_NAME_LEN_CSUM 0xDE00
1023 * EXT2_DIR_PAD defines the directory entries boundaries
1025 * NOTE: It must be a multiple of 4
1027 #define EXT2_DIR_ENTRY_HEADER_LEN 8
1028 #define EXT2_DIR_PAD 4
1029 #define EXT2_DIR_ROUND (EXT2_DIR_PAD - 1)
1030 #define EXT2_DIR_REC_LEN(name_len) (((name_len) + \
1031 EXT2_DIR_ENTRY_HEADER_LEN + \
1036 * Constants for ext4's extended time encoding
1038 #define EXT4_EPOCH_BITS 2
1039 #define EXT4_EPOCH_MASK ((1 << EXT4_EPOCH_BITS) - 1)
1040 #define EXT4_NSEC_MASK (~0UL << EXT4_EPOCH_BITS)
1043 * This structure is used for multiple mount protection. It is written
1044 * into the block number saved in the s_mmp_block field in the superblock.
1045 * Programs that check MMP should assume that if SEQ_FSCK (or any unknown
1046 * code above SEQ_MAX) is present then it is NOT safe to use the filesystem,
1047 * regardless of how old the timestamp is.
1049 * The timestamp in the MMP structure will be updated by e2fsck at some
1050 * arbitary intervals (start of passes, after every few groups of inodes
1051 * in pass1 and pass1b). There is no guarantee that e2fsck is updating
1052 * the MMP block in a timely manner, and the updates it does are purely
1053 * for the convenience of the sysadmin and not for automatic validation.
1055 * Note: Only the mmp_seq value is used to determine whether the MMP block
1056 * is being updated. The mmp_time, mmp_nodename, and mmp_bdevname
1057 * fields are only for informational purposes for the administrator,
1058 * due to clock skew between nodes and hostname HA service takeover.
1060 #define EXT4_MMP_MAGIC 0x004D4D50U /* ASCII for MMP */
1061 #define EXT4_MMP_SEQ_CLEAN 0xFF4D4D50U /* mmp_seq value for clean unmount */
1062 #define EXT4_MMP_SEQ_FSCK 0xE24D4D50U /* mmp_seq value when being fscked */
1063 #define EXT4_MMP_SEQ_MAX 0xE24D4D4FU /* maximum valid mmp_seq value */
1065 /* Not endian-annotated; it's swapped at read/write time */
1067 __u32 mmp_magic
; /* Magic number for MMP */
1068 __u32 mmp_seq
; /* Sequence no. updated periodically */
1069 __u64 mmp_time
; /* Time last updated */
1070 char mmp_nodename
[64]; /* Node which last updated MMP block */
1071 char mmp_bdevname
[32]; /* Bdev which last updated MMP block */
1072 __u16 mmp_check_interval
; /* Changed mmp_check_interval */
1074 __u32 mmp_pad2
[226];
1075 __u32 mmp_checksum
; /* crc32c(uuid+mmp_block) */
1079 * Default interval for MMP update in seconds.
1081 #define EXT4_MMP_UPDATE_INTERVAL 5
1084 * Maximum interval for MMP update in seconds.
1086 #define EXT4_MMP_MAX_UPDATE_INTERVAL 300
1089 * Minimum interval for MMP checking in seconds.
1091 #define EXT4_MMP_MIN_CHECK_INTERVAL 5
1094 * Minimum size of inline data.
1096 #define EXT4_MIN_INLINE_DATA_SIZE ((sizeof(__u32) * EXT2_N_BLOCKS))
1099 * Size of a parent inode in inline data directory.
1101 #define EXT4_INLINE_DATA_DOTDOT_SIZE (4)
1103 #endif /* _LINUX_EXT2_FS_H */