Currently, some features are not supported yet,
such as change array_sectors and update size, so
return EINVAL for them and listed it in document.
Reviewed-by: NNeilBrown <neilb@suse.com>
Signed-off-by: NGuoqing Jiang <gqjiang@suse.com>
Signed-off-by: NShaohua Li <shli@fb.com>