What: 		/config/rdma_cm
Date: 		November 29, 2015
KernelVersion:  4.4.0
Description: 	Interface is used to configure RDMA-cable HCAs in respect to
		RDMA-CM attributes.

		Attributes are visible only when configfs is mounted. To mount
		configfs in /config directory use:
		# mount -t configfs none /config/

		In order to set parameters related to a specific HCA, a directory
		for this HCA has to be created:
		mkdir -p /config/rdma_cm/<hca>


What: 		/config/rdma_cm/<hca>/ports/<port-num>/default_roce_mode
Date: 		November 29, 2015
KernelVersion:  4.4.0
Description: 	RDMA-CM based connections from HCA <hca> at port <port-num>
		will be initiated with this RoCE type as default.
		The possible RoCE types are either "IB/RoCE v1" or "RoCE v2".
		This parameter has RW access.

What: 		/config/rdma_cm/<hca>/ports/<port-num>/default_roce_tos
Date: 		February 7, 2017
KernelVersion:  4.11.0
Description: 	RDMA-CM QPs from HCA <hca> at port <port-num>
		will be created with this TOS as default.
		This can be overridden by using the rdma_set_option API.
		The possible RoCE TOS values are 0-255.