extern void llc_sap_add_socket(struct llc_sap *sap, struct sock *sk);
extern void llc_sap_remove_socket(struct llc_sap *sap, struct sock *sk);
extern void llc_sap_add_socket(struct llc_sap *sap, struct sock *sk);
extern void llc_sap_remove_socket(struct llc_sap *sap, struct sock *sk);