296 /* * Reading or writing any of these items requires holding the appropriate * lock. Field markings and the corresponding locks: * * : stable, reference to the vnode is required * f vnode_free_list_lock, or vrele_lock for vrele_list * i v_interlock * m mntvnode_lock * n namecache_lock * s syncer_data_lock * u locked by underlying filesystem * v vnode lock * x v_interlock + bufcache_lock to modify, either to inspect * * Each underlying filesystem allocates its own private area and hangs * it from v_data. */