diff --git a/net/ipv4/tcp_output.c b/net/ipv4/tcp_output.c
index ed96c54..980b98f 100644
--- a/net/ipv4/tcp_output.c
+++ b/net/ipv4/tcp_output.c
@@ -65,7 +65,7 @@
 
 
 /* Account for new data that has been sent to the network. */
-static void tcp_event_new_data_sent(struct sock *sk, struct sk_buff *skb)
+static void tcp_event_new_data_sent(struct sock *sk, const struct sk_buff *skb)
 {
 	struct tcp_sock *tp = tcp_sk(sk);
 	unsigned int prior_packets = tp->packets_out;
@@ -89,9 +89,9 @@
  * Anything in between SND.UNA...SND.UNA+SND.WND also can be already
  * invalid. OK, let's make this for now:
  */
-static inline __u32 tcp_acceptable_seq(struct sock *sk)
+static inline __u32 tcp_acceptable_seq(const struct sock *sk)
 {
-	struct tcp_sock *tp = tcp_sk(sk);
+	const struct tcp_sock *tp = tcp_sk(sk);
 
 	if (!before(tcp_wnd_end(tp), tp->snd_nxt))
 		return tp->snd_nxt;
@@ -116,7 +116,7 @@
 static __u16 tcp_advertise_mss(struct sock *sk)
 {
 	struct tcp_sock *tp = tcp_sk(sk);
-	struct dst_entry *dst = __sk_dst_get(sk);
+	const struct dst_entry *dst = __sk_dst_get(sk);
 	int mss = tp->advmss;
 
 	if (dst) {
@@ -133,7 +133,7 @@
 
 /* RFC2861. Reset CWND after idle period longer RTO to "restart window".
  * This is the first part of cwnd validation mechanism. */
-static void tcp_cwnd_restart(struct sock *sk, struct dst_entry *dst)
+static void tcp_cwnd_restart(struct sock *sk, const struct dst_entry *dst)
 {
 	struct tcp_sock *tp = tcp_sk(sk);
 	s32 delta = tcp_time_stamp - tp->lsndtime;
@@ -154,7 +154,7 @@
 
 /* Congestion state accounting after a packet has been sent. */
 static void tcp_event_data_sent(struct tcp_sock *tp,
-				struct sk_buff *skb, struct sock *sk)
+				struct sock *sk)
 {
 	struct inet_connection_sock *icsk = inet_csk(sk);
 	const u32 now = tcp_time_stamp;
@@ -295,7 +295,7 @@
 }
 
 /* Packet ECN state for a SYN-ACK */
-static inline void TCP_ECN_send_synack(struct tcp_sock *tp, struct sk_buff *skb)
+static inline void TCP_ECN_send_synack(const struct tcp_sock *tp, struct sk_buff *skb)
 {
 	TCP_SKB_CB(skb)->tcp_flags &= ~TCPHDR_CWR;
 	if (!(tp->ecn_flags & TCP_ECN_OK))
@@ -315,7 +315,7 @@
 }
 
 static __inline__ void
-TCP_ECN_make_synack(struct request_sock *req, struct tcphdr *th)
+TCP_ECN_make_synack(const struct request_sock *req, struct tcphdr *th)
 {
 	if (inet_rsk(req)->ecn_ok)
 		th->ece = 1;
@@ -565,7 +565,8 @@
  */
 static unsigned tcp_syn_options(struct sock *sk, struct sk_buff *skb,
 				struct tcp_out_options *opts,
-				struct tcp_md5sig_key **md5) {
+				struct tcp_md5sig_key **md5)
+{
 	struct tcp_sock *tp = tcp_sk(sk);
 	struct tcp_cookie_values *cvp = tp->cookie_values;
 	unsigned remaining = MAX_TCP_OPTION_SPACE;
@@ -743,7 +744,8 @@
  */
 static unsigned tcp_established_options(struct sock *sk, struct sk_buff *skb,
 					struct tcp_out_options *opts,
-					struct tcp_md5sig_key **md5) {
+					struct tcp_md5sig_key **md5)
+{
 	struct tcp_skb_cb *tcb = skb ? TCP_SKB_CB(skb) : NULL;
 	struct tcp_sock *tp = tcp_sk(sk);
 	unsigned size = 0;
@@ -893,7 +895,7 @@
 		tcp_event_ack_sent(sk, tcp_skb_pcount(skb));
 
 	if (skb->len != tcp_header_size)
-		tcp_event_data_sent(tp, skb, sk);
+		tcp_event_data_sent(tp, sk);
 
 	if (after(tcb->end_seq, tp->snd_nxt) || tcb->seq == tcb->end_seq)
 		TCP_ADD_STATS(sock_net(sk), TCP_MIB_OUTSEGS,
@@ -926,7 +928,7 @@
 }
 
 /* Initialize TSO segments for a packet. */
-static void tcp_set_skb_tso_segs(struct sock *sk, struct sk_buff *skb,
+static void tcp_set_skb_tso_segs(const struct sock *sk, struct sk_buff *skb,
 				 unsigned int mss_now)
 {
 	if (skb->len <= mss_now || !sk_can_gso(sk) ||
@@ -947,7 +949,7 @@
 /* When a modification to fackets out becomes necessary, we need to check
  * skb is counted to fackets_out or not.
  */
-static void tcp_adjust_fackets_out(struct sock *sk, struct sk_buff *skb,
+static void tcp_adjust_fackets_out(struct sock *sk, const struct sk_buff *skb,
 				   int decr)
 {
 	struct tcp_sock *tp = tcp_sk(sk);
@@ -962,7 +964,7 @@
 /* Pcount in the middle of the write queue got changed, we need to do various
  * tweaks to fix counters
  */
-static void tcp_adjust_pcount(struct sock *sk, struct sk_buff *skb, int decr)
+static void tcp_adjust_pcount(struct sock *sk, const struct sk_buff *skb, int decr)
 {
 	struct tcp_sock *tp = tcp_sk(sk);
 
@@ -1146,10 +1148,10 @@
 }
 
 /* Calculate MSS. Not accounting for SACKs here.  */
-int tcp_mtu_to_mss(struct sock *sk, int pmtu)
+int tcp_mtu_to_mss(const struct sock *sk, int pmtu)
 {
-	struct tcp_sock *tp = tcp_sk(sk);
-	struct inet_connection_sock *icsk = inet_csk(sk);
+	const struct tcp_sock *tp = tcp_sk(sk);
+	const struct inet_connection_sock *icsk = inet_csk(sk);
 	int mss_now;
 
 	/* Calculate base mss without TCP options:
@@ -1175,10 +1177,10 @@
 }
 
 /* Inverse of above */
-int tcp_mss_to_mtu(struct sock *sk, int mss)
+int tcp_mss_to_mtu(const struct sock *sk, int mss)
 {
-	struct tcp_sock *tp = tcp_sk(sk);
-	struct inet_connection_sock *icsk = inet_csk(sk);
+	const struct tcp_sock *tp = tcp_sk(sk);
+	const struct inet_connection_sock *icsk = inet_csk(sk);
 	int mtu;
 
 	mtu = mss +
@@ -1252,8 +1254,8 @@
  */
 unsigned int tcp_current_mss(struct sock *sk)
 {
-	struct tcp_sock *tp = tcp_sk(sk);
-	struct dst_entry *dst = __sk_dst_get(sk);
+	const struct tcp_sock *tp = tcp_sk(sk);
+	const struct dst_entry *dst = __sk_dst_get(sk);
 	u32 mss_now;
 	unsigned header_len;
 	struct tcp_out_options opts;
@@ -1313,10 +1315,10 @@
  * modulo only when the receiver window alone is the limiting factor or
  * when we would be allowed to send the split-due-to-Nagle skb fully.
  */
-static unsigned int tcp_mss_split_point(struct sock *sk, struct sk_buff *skb,
+static unsigned int tcp_mss_split_point(const struct sock *sk, const struct sk_buff *skb,
 					unsigned int mss_now, unsigned int cwnd)
 {
-	struct tcp_sock *tp = tcp_sk(sk);
+	const struct tcp_sock *tp = tcp_sk(sk);
 	u32 needed, window, cwnd_len;
 
 	window = tcp_wnd_end(tp) - TCP_SKB_CB(skb)->seq;
@@ -1336,8 +1338,8 @@
 /* Can at least one segment of SKB be sent right now, according to the
  * congestion window rules?  If so, return how many segments are allowed.
  */
-static inline unsigned int tcp_cwnd_test(struct tcp_sock *tp,
-					 struct sk_buff *skb)
+static inline unsigned int tcp_cwnd_test(const struct tcp_sock *tp,
+					 const struct sk_buff *skb)
 {
 	u32 in_flight, cwnd;
 
@@ -1358,7 +1360,7 @@
  * This must be invoked the first time we consider transmitting
  * SKB onto the wire.
  */
-static int tcp_init_tso_segs(struct sock *sk, struct sk_buff *skb,
+static int tcp_init_tso_segs(const struct sock *sk, struct sk_buff *skb,
 			     unsigned int mss_now)
 {
 	int tso_segs = tcp_skb_pcount(skb);
@@ -1396,7 +1398,7 @@
 /* Return non-zero if the Nagle test allows this packet to be
  * sent now.
  */
-static inline int tcp_nagle_test(struct tcp_sock *tp, struct sk_buff *skb,
+static inline int tcp_nagle_test(const struct tcp_sock *tp, const struct sk_buff *skb,
 				 unsigned int cur_mss, int nonagle)
 {
 	/* Nagle rule does not apply to frames, which sit in the middle of the
@@ -1422,7 +1424,7 @@
 }
 
 /* Does at least the first segment of SKB fit into the send window? */
-static inline int tcp_snd_wnd_test(struct tcp_sock *tp, struct sk_buff *skb,
+static inline int tcp_snd_wnd_test(const struct tcp_sock *tp, const struct sk_buff *skb,
 				   unsigned int cur_mss)
 {
 	u32 end_seq = TCP_SKB_CB(skb)->end_seq;
@@ -1437,10 +1439,10 @@
  * should be put on the wire right now.  If so, it returns the number of
  * packets allowed by the congestion window.
  */
-static unsigned int tcp_snd_test(struct sock *sk, struct sk_buff *skb,
+static unsigned int tcp_snd_test(const struct sock *sk, struct sk_buff *skb,
 				 unsigned int cur_mss, int nonagle)
 {
-	struct tcp_sock *tp = tcp_sk(sk);
+	const struct tcp_sock *tp = tcp_sk(sk);
 	unsigned int cwnd_quota;
 
 	tcp_init_tso_segs(sk, skb, cur_mss);
@@ -1458,7 +1460,7 @@
 /* Test if sending is allowed right now. */
 int tcp_may_send_now(struct sock *sk)
 {
-	struct tcp_sock *tp = tcp_sk(sk);
+	const struct tcp_sock *tp = tcp_sk(sk);
 	struct sk_buff *skb = tcp_send_head(sk);
 
 	return skb &&
@@ -2008,7 +2010,7 @@
 }
 
 /* Check if coalescing SKBs is legal. */
-static int tcp_can_collapse(struct sock *sk, struct sk_buff *skb)
+static int tcp_can_collapse(const struct sock *sk, const struct sk_buff *skb)
 {
 	if (tcp_skb_pcount(skb) > 1)
 		return 0;
@@ -2184,7 +2186,7 @@
 static int tcp_can_forward_retransmit(struct sock *sk)
 {
 	const struct inet_connection_sock *icsk = inet_csk(sk);
-	struct tcp_sock *tp = tcp_sk(sk);
+	const struct tcp_sock *tp = tcp_sk(sk);
 
 	/* Forward retransmissions are possible only during Recovery. */
 	if (icsk->icsk_ca_state != TCP_CA_Recovery)
@@ -2550,7 +2552,7 @@
 /* Do all connect socket setups that can be done AF independent. */
 static void tcp_connect_init(struct sock *sk)
 {
-	struct dst_entry *dst = __sk_dst_get(sk);
+	const struct dst_entry *dst = __sk_dst_get(sk);
 	struct tcp_sock *tp = tcp_sk(sk);
 	__u8 rcv_wscale;