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ext2・ext3・ext4ファイルシステムの情報を表示するにはdumpe2fsコマンドを使用します。
※ここでは例として、ファイルシステムがext4の/dev/mmcblk0p2の情報を表示します。

[armadillo ~]# df -Tt ext4
Filesystem     Type 1K-blocks   Used Available Use% Mounted on
/dev/mmcblk0p2 ext4   3424176 657008   2573512  21% /
[armadillo ~]# dumpe2fs /dev/mmcblk0p2
dumpe2fs 1.44.5 (15-Dec-2018)
Filesystem volume name:   <none>
Last mounted on:          /
Filesystem UUID:          d5e36677-0657-4e29-911d-7d1e54e554d1
Filesystem magic number:  0xEF53
Filesystem revision #:    1 (dynamic)
Filesystem features:      has_journal ext_attr resize_inode dir_index filetype needs_recovery extent flex_bg sparse_super large_file huge_file uninit_bg dir_nlink extra_isize
：（省略）
Group 27: (Blocks 884736-886359) csum 0x4090 [INODE_UNINIT, ITABLE_ZEROED]
  Backup superblock at 884736, Group descriptors at 884737-884737
  Reserved GDT blocks at 884738-884953
  Block bitmap at 524299 (bg #16 + 11)
  Inode bitmap at 524315 (bg #16 + 27)
  Inode table at 529765-530259 (bg #16 + 5477)
  1406 free blocks, 7920 free inodes, 0 directories, 7920 unused inodes
  Free blocks: 884954-886359
  Free inodes: 213841-221760

スーパーブロックのみ表示するには-hオプションを使用します。

[armadillo ~]# dumpe2fs /dev/mmcblk0p2 -h
dumpe2fs 1.44.5 (15-Dec-2018)
Filesystem volume name:   <none>
Last mounted on:          /
Filesystem UUID:          d5e36677-0657-4e29-911d-7d1e54e554d1
Filesystem magic number:  0xEF53
Filesystem revision #:    1 (dynamic)
Filesystem features:      has_journal ext_attr resize_inode dir_index filetype needs_recovery extent flex_bg sparse_super large_file huge_file uninit_bg dir_nlink extra_isize
Filesystem flags:         unsigned_directory_hash
Default mount options:    user_xattr acl
Filesystem state:         clean
Errors behavior:          Continue
Filesystem OS type:       Linux
Inode count:              221760
Block count:              886360
Reserved block count:     44318
Free blocks:              693055
Free inodes:              203454
First block:              0
Block size:               4096
Fragment size:            4096
Reserved GDT blocks:      216
Blocks per group:         32768
Fragments per group:      32768
Inodes per group:         7920
Inode blocks per group:   495
Flex block group size:    16
Filesystem created:       Thu Jan  1 09:00:18 1970
Last mount time:          Thu Feb 14 19:12:00 2019
Last write time:          Thu Jan  1 09:02:23 1970
Mount count:              115
Maximum mount count:      -1
Last checked:             Thu Jan  1 09:00:18 1970
Check interval:           0 (<none>)
Lifetime writes:          6310 MB
Reserved blocks uid:      0 (user root)
Reserved blocks gid:      0 (group root)
First inode:              11
Inode size:               256
Required extra isize:     28
Desired extra isize:      28
Journal inode:            8
Default directory hash:   half_md4
Directory Hash Seed:      31627d6c-8337-493e-af6f-c5bb5dff8870
Journal backup:           inode blocks
Journal features:         journal_incompat_revoke
Journal size:             64M
Journal length:           16384
Journal sequence:         0x00001062
Journal start:            1