taglinefilesource code
ow_size5181net/ipv4/tcp.cunsigned long ow_size;
ow_size5276net/ipv4/tcp.cow_size = skb->len - win_size - 
ow_size5279net/ipv4/tcp.cmemmove(tcp_data_start, tcp_data_start + win_size, ow_size);