Commits
Song Liu committed bac624f3f86
MD: add a new disk role to present write journal device Next patches will use a disk as raid5/6 journaling. We need a new disk role to present the journal device and add MD_FEATURE_JOURNAL to feature_map for backward compability. Signed-off-by: Song Liu <songliubraving@fb.com> Signed-off-by: Shaohua Li <shli@fb.com> Signed-off-by: NeilBrown <neilb@suse.com>