kinit/fstype/ext2_fs.h

/*
 * The second extended file system magic number
 */
#define EXT2_SUPER_MAGIC	0xEF53

/*
 * Structure of the super block
 */
struct ext2_super_block {
	__le32 s_inodes_count;	/* Inodes count */
	__le32 s_blocks_count;	/* Blocks count */
	__le32 s_r_blocks_count;	/* Reserved blocks count */
	__le32 s_free_blocks_count;	/* Free blocks count */
	__le32 s_free_inodes_count;	/* Free inodes count */
	__le32 s_first_data_block;	/* First Data Block */
	__le32 s_log_block_size;	/* Block size */
	__le32 s_log_frag_size;	/* Fragment size */
	__le32 s_blocks_per_group;	/* # Blocks per group */
	__le32 s_frags_per_group;	/* # Fragments per group */
	__le32 s_inodes_per_group;	/* # Inodes per group */
	__le32 s_mtime;		/* Mount time */
	__le32 s_wtime;		/* Write time */
	__le16 s_mnt_count;	/* Mount count */
	__le16 s_max_mnt_count;	/* Maximal mount count */
	__le16 s_magic;		/* Magic signature */
	__le16 s_state;		/* File system state */
	__le16 s_errors;	/* Behaviour when detecting errors */
	__le16 s_minor_rev_level;	/* minor revision level */
	__le32 s_lastcheck;	/* time of last check */
	__le32 s_checkinterval;	/* max. time between checks */
	__le32 s_creator_os;	/* OS */
	__le32 s_rev_level;	/* Revision level */
	__le16 s_def_resuid;	/* Default uid for reserved blocks */
	__le16 s_def_resgid;	/* Default gid for reserved blocks */
	/*
	 * These fields are for EXT2_DYNAMIC_REV superblocks only.
	 *
	 * Note: the difference between the compatible feature set and
	 * the incompatible feature set is that if there is a bit set
	 * in the incompatible feature set that the kernel doesn't
	 * know about, it should refuse to mount the filesystem.
	 *
	 * e2fsck's requirements are more strict; if it doesn't know
	 * about a feature in either the compatible or incompatible
	 * feature set, it must abort and not try to meddle with
	 * things it doesn't understand...
	 */
	__le32 s_first_ino;	/* First non-reserved inode */
	__le16 s_inode_size;	/* size of inode structure */
	__le16 s_block_group_nr;	/* block group # of this superblock */
	__le32 s_feature_compat;	/* compatible feature set */
	__le32 s_feature_incompat;	/* incompatible feature set */
	__le32 s_feature_ro_compat;	/* readonly-compatible feature set */
	__u8 s_uuid[16];	/* 128-bit uuid for volume */
	char s_volume_name[16];	/* volume name */
	char s_last_mounted[64];	/* directory where last mounted */
	__le32 s_algorithm_usage_bitmap;	/* For compression */
	/*
	 * Performance hints.  Directory preallocation should only
	 * happen if the EXT2_COMPAT_PREALLOC flag is on.
	 */
	__u8 s_prealloc_blocks;	/* Nr of blocks to try to preallocate */
	__u8 s_prealloc_dir_blocks;	/* Nr to preallocate for dirs */
	__u16 s_padding1;
	/*
	 * Journaling support valid if EXT3_FEATURE_COMPAT_HAS_JOURNAL set.
	 */
	__u8 s_journal_uuid[16];	/* uuid of journal superblock */
	__u32 s_journal_inum;	/* inode number of journal file */
	__u32 s_journal_dev;	/* device number of journal file */
	__u32 s_last_orphan;	/* start of list of inodes to delete */
	__u32 s_hash_seed[4];	/* HTREE hash seed */
	__u8 s_def_hash_version;	/* Default hash version to use */
	__u8 s_reserved_char_pad;
	__u16 s_reserved_word_pad;
	__le32 s_default_mount_opts;
	__le32 s_first_meta_bg;	/* First metablock block group */
	__u32 s_reserved[190];	/* Padding to the end of the block */
};
1	/*
2	* The second extended file system magic number
3	*/
4	#define EXT2_SUPER_MAGIC 0xEF53
5
6	/*
7	* Structure of the super block
8	*/
9	struct ext2_super_block {
10	__le32 s_inodes_count; /* Inodes count */
11	__le32 s_blocks_count; /* Blocks count */
12	__le32 s_r_blocks_count; /* Reserved blocks count */
13	__le32 s_free_blocks_count; /* Free blocks count */
14	__le32 s_free_inodes_count; /* Free inodes count */
15	__le32 s_first_data_block; /* First Data Block */
16	__le32 s_log_block_size; /* Block size */
17	__le32 s_log_frag_size; /* Fragment size */
18	__le32 s_blocks_per_group; /* # Blocks per group */
19	__le32 s_frags_per_group; /* # Fragments per group */
20	__le32 s_inodes_per_group; /* # Inodes per group */
21	__le32 s_mtime; /* Mount time */
22	__le32 s_wtime; /* Write time */
23	__le16 s_mnt_count; /* Mount count */
24	__le16 s_max_mnt_count; /* Maximal mount count */
25	__le16 s_magic; /* Magic signature */
26	__le16 s_state; /* File system state */
27	__le16 s_errors; /* Behaviour when detecting errors */
28	__le16 s_minor_rev_level; /* minor revision level */
29	__le32 s_lastcheck; /* time of last check */
30	__le32 s_checkinterval; /* max. time between checks */
31	__le32 s_creator_os; /* OS */
32	__le32 s_rev_level; /* Revision level */
33	__le16 s_def_resuid; /* Default uid for reserved blocks */
34	__le16 s_def_resgid; /* Default gid for reserved blocks */
35	/*
36	* These fields are for EXT2_DYNAMIC_REV superblocks only.
37	*
38	* Note: the difference between the compatible feature set and
39	* the incompatible feature set is that if there is a bit set
40	* in the incompatible feature set that the kernel doesn't
41	* know about, it should refuse to mount the filesystem.
42	*
43	* e2fsck's requirements are more strict; if it doesn't know
44	* about a feature in either the compatible or incompatible
45	* feature set, it must abort and not try to meddle with
46	* things it doesn't understand...
47	*/
48	__le32 s_first_ino; /* First non-reserved inode */
49	__le16 s_inode_size; /* size of inode structure */
50	__le16 s_block_group_nr; /* block group # of this superblock */
51	__le32 s_feature_compat; /* compatible feature set */
52	__le32 s_feature_incompat; /* incompatible feature set */
53	__le32 s_feature_ro_compat; /* readonly-compatible feature set */
54	__u8 s_uuid[16]; /* 128-bit uuid for volume */
55	char s_volume_name[16]; /* volume name */
56	char s_last_mounted[64]; /* directory where last mounted */
57	__le32 s_algorithm_usage_bitmap; /* For compression */
58	/*
59	* Performance hints. Directory preallocation should only
60	* happen if the EXT2_COMPAT_PREALLOC flag is on.
61	*/
62	__u8 s_prealloc_blocks; /* Nr of blocks to try to preallocate */
63	__u8 s_prealloc_dir_blocks; /* Nr to preallocate for dirs */
64	__u16 s_padding1;
65	/*
66	* Journaling support valid if EXT3_FEATURE_COMPAT_HAS_JOURNAL set.
67	*/
68	__u8 s_journal_uuid[16]; /* uuid of journal superblock */
69	__u32 s_journal_inum; /* inode number of journal file */
70	__u32 s_journal_dev; /* device number of journal file */
71	__u32 s_last_orphan; /* start of list of inodes to delete */
72	__u32 s_hash_seed[4]; /* HTREE hash seed */
73	__u8 s_def_hash_version; /* Default hash version to use */
74	__u8 s_reserved_char_pad;
75	__u16 s_reserved_word_pad;
76	__le32 s_default_mount_opts;
77	__le32 s_first_meta_bg; /* First metablock block group */
78	__u32 s_reserved[190]; /* Padding to the end of the block */
79	};