Dixi quod…
>= /dev/dm-8
>dumpe2fs 1.46.2 (28-Feb-2021)
>Inode count: 65536
>Inodes per group: 8192
>Inode blocks per group: 256
>Inode size: 128
Let’s look at the superblock, first here, for orienting.
00000430 fe 6b 25 67 02 00 ff ff 53 ef 01 00 01 00 00 00 |.k%g....S.......|
00000440 89 6b 25 67 00 00 00 00 00 00 00 00 01 00 00 00 |.k%g............|
00000450 00 00 00 00 0b 00 00 00 80 00 00 00 3c 00 00 00 |............<...|
438h has, for orientation, e2fs_magic. Going forward…
458h has u_int16_t e2fs_inode_size. 0080h = 128, fits.
>= /dev/dm-5
>dumpe2fs 1.46.2 (28-Feb-2021)
>Inode count: 262144
>Inodes per group: 8192
>Inode blocks per group: 256
00000430 ea 62 25 67 02 00 ff ff 53 ef 00 00 01 00 00 00 |.b%g....S.......|
00000440 80 4e 25 67 00 00 00 00 00 00 00 00 00 00 00 00 |.N%g............|
00000450 00 00 00 00 0b 00 00 00 80 00 00 00 00 00 00 00 |................|
Huh, 0080h as well. (Maybe I did explicitly use -I 256 when
creating the root filesystem, after all?)
But why is it not reported? I’d have half expected 0000h…
In addition, if I umount and remount it, the kernel does not
complain about the too-small inode size being a Y2038 problem,
unlike for dm-8… what is happening here?
Let’s look at a 256-sized one…
>= /dev/dm-2
>dumpe2fs 1.46.2 (28-Feb-2021)
>Inode count: 327680
>Inodes per group: 8192
>Inode blocks per group: 512
>Inode size: 256
00000430 e4 62 25 67 01 00 ff ff 53 ef 01 00 01 00 00 00 |.b%g....S.......|
00000440 e3 62 25 67 00 00 00 00 00 00 00 00 01 00 00 00 |.b%g............|
00000450 00 00 00 00 0b 00 00 00 00 01 00 00 3c 00 00 00 |............<...|
0100h, as expected. So I have reasonable ground to assume that
/dev/dm-5 indeed has 128-byte inodes… except:
[defaults]
inode_size = 256
[fs_types]
ext4 = {
features =
has_journal,extent,huge_file,flex_bg,metadata_csum,64bit,dir_nlink,extra_isize
inode_size = 256
}
What am I missing? Did I found another bug in mke2fs in that it
creates filesystems sometimes with smaller inode sizes after all
and/or a bug in the kernel that it does not report for some fs
with 128-byte inodes?
Confused,
//mirabilos
--
> Hi, does anyone sell openbsd stickers by themselves and not packaged
> with other products?
No, the only way I've seen them sold is for $40 with a free OpenBSD CD.
-- Haroon Khalid and Steve Shockley in gmane.os.openbsd.misc
