How to clear the target connection via add_target

Hello experts,

I missed to create the target connection via add_target. as follows.

(ex.)

# echo "id_ext=0002c90300xxxxxx,ioc_guid=0002c90300xxxxxx,dgid=fe80000000000000000xxxxxx,pkey=ffff,service_id=000xxxxxx" > /sys/class/infiniband_srp/srp-mlx4_0-1/add_target

Please show me how to clear this setup.

Thanks in advance,