docs: ext4: modify the group desc size to 64

Since the default ext4 group desc size is 64 now (assuming that the
64-bit feature is enbled). And the size mentioned in this doc is 64 too.
Change it to 64.

Signed-off-by: Wu Bo <bo.wu@vivo.com>
Acked-by: Darrick J. Wong <djwong@kernel.org>
Link: https://lore.kernel.org/r/20230222013525.14748-1-bo.wu@vivo.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
This commit is contained in:
Wu Bo 2023-02-22 09:35:24 +08:00 committed by Theodore Ts'o
parent c993799baf
commit b7eef407e5

View file

@ -105,9 +105,9 @@ descriptors. Instead, the superblock and a single block group descriptor
block is placed at the beginning of the first, second, and last block
groups in a meta-block group. A meta-block group is a collection of
block groups which can be described by a single block group descriptor
block. Since the size of the block group descriptor structure is 32
bytes, a meta-block group contains 32 block groups for filesystems with
a 1KB block size, and 128 block groups for filesystems with a 4KB
block. Since the size of the block group descriptor structure is 64
bytes, a meta-block group contains 16 block groups for filesystems with
a 1KB block size, and 64 block groups for filesystems with a 4KB
blocksize. Filesystems can either be created using this new block group
descriptor layout, or existing filesystems can be resized on-line, and
the field s_first_meta_bg in the superblock will indicate the first