• NeilBrown's avatar
    md: allow a partially recovered device to be hot-added to an array. · 7eb41885
    NeilBrown authored
    
    
    When adding a new device into an array it is normally important to
    clear any stale data from ->recovery_offset else the new device may
    not be recovered properly.
    
    However when re-adding a device which is known to be nearly in-sync,
    this is not needed and can be detrimental.  The (bitmap-based)
    resync will still happen, and further recovery is only needed from
    where-ever it was already up to.
    
    So if save_raid_disk is set, signifying a re-add, don't clear
    ->recovery_offset.
    
    Signed-off-by: default avatarNeilBrown <neilb@suse.de>
    7eb41885