lockmgr_disowned
(!lockmgr_xlocked(lk) && !lockmgr_disowned(lk)))))
if (!lockmgr_xlocked(lk) && !lockmgr_disowned(lk))
if (lockmgr_xlocked(lk) || lockmgr_disowned(lk))
if (!lockmgr_disowned(lk)) {
lockmgr_disowned(&(bp)->b_lock)