static bool tcp_try_coalesce(struct sock *sk,
			     struct sk_buff *to,
			     struct sk_buff *from,
			     bool *fragstolen)
{
	int delta;

	*fragstolen = false;

	/* Its possible this segment overlaps with prior segment in queue */
	if (TCP_SKB_CB(from)->seq != TCP_SKB_CB(to)->end_seq)
		return false;

#ifdef CONFIG_TLS_DEVICE
	if (from->decrypted != to->decrypted)
		return false;
#endif

	if (!skb_try_coalesce(to, from, fragstolen, &delta))
		return false;

	atomic_add(delta, &sk->sk_rmem_alloc);
	sk_mem_charge(sk, delta);
	NET_INC_STATS(sock_net(sk), LINUX_MIB_TCPRCVCOALESCE);
	TCP_SKB_CB(to)->end_seq = TCP_SKB_CB(from)->end_seq;
	TCP_SKB_CB(to)->ack_seq = TCP_SKB_CB(from)->ack_seq;
	TCP_SKB_CB(to)->tcp_flags |= TCP_SKB_CB(from)->tcp_flags;

	if (TCP_SKB_CB(from)->has_rxtstamp) {
		TCP_SKB_CB(to)->has_rxtstamp = true;
		to->tstamp = from->tstamp;
		skb_hwtstamps(to)->hwtstamp = skb_hwtstamps(from)->hwtstamp;
	}

	return true;
}
static bool tcp_try_coalesce(struct sock *sk,
			     struct sk_buff *to,
			     struct sk_buff *from,
			     bool *fragstolen)
{
	int delta;

	*fragstolen = false;

	 
	if (TCP_SKB_CB(from)->seq != TCP_SKB_CB(to)->end_seq)
		return false;

#ifdef CONFIG_TLS_DEVICE
	if (from->decrypted != to->decrypted)
		return false;
#endif

	if (!skb_try_coalesce(to, from, fragstolen, &delta))
		return false;

	atomic_add(delta, &sk->sk_rmem_alloc);
	sk_mem_charge(sk, delta);
	NET_INC_STATS(sock_net(sk), LINUX_MIB_TCPRCVCOALESCE);
	TCP_SKB_CB(to)->end_seq = TCP_SKB_CB(from)->end_seq;
	TCP_SKB_CB(to)->ack_seq = TCP_SKB_CB(from)->ack_seq;
	TCP_SKB_CB(to)->tcp_flags |= TCP_SKB_CB(from)->tcp_flags;

	if (TCP_SKB_CB(from)->has_rxtstamp) {
		TCP_SKB_CB(to)->has_rxtstamp = true;
		to->tstamp = from->tstamp;
		skb_hwtstamps(to)->hwtstamp = skb_hwtstamps(from)->hwtstamp;
	}

	return true;
}