Allow client to query RDMA informations

Merge together the UDP exchange example with the server side of the
RDMA example.

rdma_server.c

@@ -15,8 +15,11 @@ int main(void) {
 	struct ibv_cq *ibv_dev_cq;
 	struct ibv_qp *ibv_dev_qp;
 	struct ibv_mr *ibv_dev_mr;
+	struct ibv_port_attr ibv_dev_attr;
+	struct udp_rdma_parameters local_params;
 
 	void *memory_buffer;
+	int result;
 	int allocated_size = 16384 * sizeof(char);
 	int page_size = sysconf(_SC_PAGESIZE);
 
@@ -67,7 +70,34 @@ int main(void) {
 		return -1;
 	}
 
-	// Global cleanup
+	/******************************
+	 **** Exchange informations ***
+	 ******************************/
+	result = ibv_query_port(ibv_dev_ctx, 1, &ibv_dev_attr);
+	if(result) {
+		perror("Query port failed");
+		return -1;
+	}
+
+	// Setup a server for sending RDMA parameters
+	local_params.lid = ibv_dev_attr.lid;
+	local_params.qpn = ibv_dev_qp->qp_num;
+	local_params.psn = lrand48() & 0xffffff;
+	local_params.addr = ibv_dev_mr->addr;
+	local_params.size = ibv_dev_mr->length;
+	local_params.key = ibv_dev_mr->rkey;
+
+	printf("LID: %d | QPN: %d | PSN: %d\n", local_params.lid, local_params.qpn, local_params.psn);
+
+	if(!serve_rdma_udp_parameters(&local_params)) {
+		return -1;
+	}
+
+	printf("Parameters sent to peer\n");
+
+	/******************************
+	 ******* Global cleanup *******
+	 ******************************/
 	ibv_destroy_qp(ibv_dev_qp);
 	ibv_destroy_cq(ibv_dev_cq);
 	ibv_dereg_mr(ibv_dev_mr);

udp_rdma.h

@@ -22,6 +22,7 @@ struct udp_query_parameters {
 struct udp_rdma_parameters {
 	uint16_t lid;
 	uint32_t qpn;
+	uint32_t psn;
 	void *addr;
 	size_t size;
 	uint32_t key;