Superblock

Superblock

The superblock contains meta information about the file system. The superblock is located at byte offset 1024 from the beginning of the file, block device or partition formatted with FFS. The superblock is fully located in the first block of the file system - block 0.

Starting Byte	Ending Byte	Size In Bytes	Field Description
0	3	4	Total number of inodes
4	7	4	Total number of blocks
8	11	4
12	15	4	Total number of unallocated blocks
16	19	4	Total number of unallocated inodes
20	23	4
24	27	4	log2(block size) - 10 = 1
28	31	4	log2(fragment size) - 10 = 1
32	35	4	Number of blocks in each block group = 2048
36	39	4	Number of fragments in each block group = 2048
40	43	4	Number of inodes in each block group = 2048
44	53	10
54	55	2	Number of mounts allowed before a consistency check must be done = 0xffff
56	57	2	ext2fs signature = 0xEF53
58	59	2	File system state = 1 (file system is clean)
60	61	2	Error Handling Method = 1 (ignore)
62	63	2	Minor revision number = 0
64	67	4
68	71	4	Interval between forced consistency checks = 0xffffffff
72	75	4
68	71	4	Major reviosion number = 0
72	1023	944