RXRPC_CIDSHIFT
conn->proto.cid = id << RXRPC_CIDSHIFT;
id = conn->proto.cid >> RXRPC_CIDSHIFT;
idr_remove(&local->conn_ids, conn->proto.cid >> RXRPC_CIDSHIFT);
conn = idr_find(&local->conn_ids, sp->hdr.cid >> RXRPC_CIDSHIFT);
#define RXRPC_CID_INC (1 << RXRPC_CIDSHIFT) /* connection ID increment */
x = (call->cid & RXRPC_CHANNELMASK) << (32 - RXRPC_CIDSHIFT);
x = (call->cid & RXRPC_CHANNELMASK) << (32 - RXRPC_CIDSHIFT);