RDMA/cma: Add support for AF_IB to cma_get_service_id()

cma_get_service_id() forms the service ID based on the port space and
port number of the rdma_cm_id.  Extend the call to support AF_IB,
which contains the service ID directly.  This will be needed to
support any arbitrary SID.

Signed-off-by: Sean Hefty <sean.hefty@intel.com>
Signed-off-by: Roland Dreier <roland@purestorage.com>

drivers/infiniband/core/cma.c

@@ -1379,6 +1379,9 @@ err1:
 
 static __be64 cma_get_service_id(enum rdma_port_space ps, struct sockaddr *addr)
 {
+	if (addr->sa_family == AF_IB)
+		return ((struct sockaddr_ib *) addr)->sib_sid;
+
 	return cpu_to_be64(((u64)ps << 16) + be16_to_cpu(cma_port(addr)));
 }