ext4: store checksum seed in superblock
authorDarrick J. Wong <darrick.wong@oracle.com>
Sat, 17 Oct 2015 20:16:02 +0000 (16:16 -0400)
committerTheodore Ts'o <tytso@mit.edu>
Sat, 17 Oct 2015 20:16:02 +0000 (16:16 -0400)
commit8c81bd8f586c46eaf114758a78d82895a2b081c2
treef23c8117906fa29aa0ad3890dd5a2faa8d8ed811
parent8b4953e13f4c5d9a3c869f5fca7d51e1700e7db0
ext4: store checksum seed in superblock

Allow the filesystem to store the metadata checksum seed in the
superblock and add an incompat feature to say that we're using it.
This enables tune2fs to change the UUID on a mounted metadata_csum
FS without having to (racy!) rewrite all disk metadata.

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
fs/ext4/ext4.h
fs/ext4/super.c
fs/ext4/sysfs.c