net/rds: Use rdma_read_gids to read connection GIDs

Use the newly introduced rdma_read_gids() to read the SGID and DGID for
the connection which returns GID correctly for RoCE transport as well.

rdma_addr_get_dgid() for RoCE for client side connections returns MAC
address, instead of DGID.
rdma_addr_get_sgid() for RoCE doesn't return correct SGID for IPv6 and
when more than one IP address is assigned to the netdevice.

Therefore use transport agnostic rdma_read_gids() API provided by rdma_cm
module.
Signed-off-by: Parav Pandit <parav@mellanox.com>
Reviewed-by: Daniel Jurgens <danielj@mellanox.com>
Acked-by: Santosh Shilimkar <santosh.shilimkar@oracle.com>
Signed-off-by: Leon Romanovsky <leon@kernel.org>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>

net/rds/ib.c

@@ -301,13 +301,11 @@ static int rds_ib_conn_info_visitor(struct rds_connection *conn,
 	memset(&iinfo->dst_gid, 0, sizeof(iinfo->dst_gid));
 	if (rds_conn_state(conn) == RDS_CONN_UP) {
 		struct rds_ib_device *rds_ibdev;
-		struct rdma_dev_addr *dev_addr;
 
 		ic = conn->c_transport_data;
-		dev_addr = &ic->i_cm_id->route.addr.dev_addr;
 
-		rdma_addr_get_sgid(dev_addr, (union ib_gid *) &iinfo->src_gid);
-		rdma_addr_get_dgid(dev_addr, (union ib_gid *) &iinfo->dst_gid);
+		rdma_read_gids(ic->i_cm_id, (union ib_gid *)&iinfo->src_gid,
+			       (union ib_gid *)&iinfo->dst_gid);
 
 		rds_ibdev = ic->rds_ibdev;
 		iinfo->max_send_wr = ic->i_send_ring.w_nr;