a0ae7e4e0bc0 ("md: factor out a helper rdev_addable() from remove_and_add_spares()")
b172a0704d0d ("md: factor out a helper rdev_is_spare() from remove_and_add_spares()")
3389d57f9753 ("md: factor out a helper rdev_removeable() from remove_and_add_spares()")
f97a5528b21e ("md: introduce md_ro_state")