rds_ib_get_device
rds_ibdev = rds_ib_get_device(addr->s6_addr32[3]);
struct rds_ib_device *rds_ib_get_device(__be32 ipaddr);
rds_ibdev_old = rds_ib_get_device(ipaddr->s6_addr32[3]);
rds_ibdev = rds_ib_get_device(rs->rs_bound_addr.s6_addr32[3]);