rds/ib: Preserve dest qp num in the connect request

Commit 227fb00 ("rds/rdma: correctly assign the dest qp num in rds ib
connection") fixed the dest qp num issue for the passive side. But if a new
connect request comes for an existing connection and if RDS yields to this
incoming connection, then it does not preserve the dest qp num. Hence it
causes the rds-info command to show a stale destination qp number. This
patch fixes the issue by storing the dest qp number from the incoming
connect request.

Fixes: 227fb00 ("rds/rdma: correctly assign the dest qp num in rds ib connection")
Orabug: 35926163

Signed-off-by: Arumugam Kolappan <[email protected]>
Reviewed-by: Håkon Bugge <[email protected]>

Author: Arumugam Kolappan

net/rds/ib.h

@@ -293,6 +293,7 @@ struct rds_ib_connection {
 		u32			 version;
 		u8			 responder_resources;
 		u8			 initiator_depth;
+		s32			 dst_qp_num;
 	} i_alt;
 
 	/* Number of wrs available for MR registration(frwr) */

net/rds/ib_cm.c

@@ -2093,6 +2093,7 @@ int rds_ib_cm_handle_connect(struct rdma_cm_id *cm_id,
 			ic->i_alt.cm_id = cm_id;
 			ic->i_alt.is_stale = false;
 			ic->i_alt.isv6 = isv6;
+			ic->i_alt.dst_qp_num = event->param.conn.qp_num;
 			memcpy(&ic->i_alt.private_data, dp,
 			       sizeof(ic->i_alt.private_data));
 			ic->i_alt.version = version;
@@ -2128,7 +2129,7 @@ int rds_ib_cm_handle_connect(struct rdma_cm_id *cm_id,
 				       event->param.conn.initiator_depth);
 		if (err)
 			reason = "rds_ib_cm_accept failed";
-		else if (event->param.conn.qp_num)
+		else
 			ic->i_dst_qp_num = event->param.conn.qp_num;
 	}
 
@@ -2331,6 +2332,8 @@ int rds_ib_conn_path_connect(struct rds_conn_path *cp)
 				       ic->i_alt.responder_resources,
 				       ic->i_alt.initiator_depth);
 
+		if (!ret)
+			ic->i_dst_qp_num = ic->i_alt.dst_qp_num;
 		ic->i_alt.cm_id = NULL;
 		mutex_unlock(&conn->c_cm_lock);