inet/connection_sock: Convert timers to use timer_setup()

In preparation for unconditionally passing the struct timer_list pointer to
all timer callbacks, switch to using the new timer_setup() and from_timer()
to pass the timer pointer explicitly.

Cc: "David S. Miller" <davem@davemloft.net>
Cc: Gerrit Renker <gerrit@erg.abdn.ac.uk>
Cc: Alexey Kuznetsov <kuznet@ms2.inr.ac.ru>
Cc: Hideaki YOSHIFUJI <yoshfuji@linux-ipv6.org>
Cc: netdev@vger.kernel.org
Cc: dccp@vger.kernel.org
Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/ipv4/tcp_timer.c b/net/ipv4/tcp_timer.c
index 7014cc0..804a8d3 100644
--- a/net/ipv4/tcp_timer.c
+++ b/net/ipv4/tcp_timer.c
@@ -288,15 +288,17 @@ void tcp_delack_timer_handler(struct sock *sk)
  *
  *  Returns: Nothing (void)
  */
-static void tcp_delack_timer(unsigned long data)
+static void tcp_delack_timer(struct timer_list *t)
 {
-	struct sock *sk = (struct sock *)data;
+	struct inet_connection_sock *icsk =
+			from_timer(icsk, t, icsk_delack_timer);
+	struct sock *sk = &icsk->icsk_inet.sk;
 
 	bh_lock_sock(sk);
 	if (!sock_owned_by_user(sk)) {
 		tcp_delack_timer_handler(sk);
 	} else {
-		inet_csk(sk)->icsk_ack.blocked = 1;
+		icsk->icsk_ack.blocked = 1;
 		__NET_INC_STATS(sock_net(sk), LINUX_MIB_DELAYEDACKLOCKED);
 		/* deleguate our work to tcp_release_cb() */
 		if (!test_and_set_bit(TCP_DELACK_TIMER_DEFERRED, &sk->sk_tsq_flags))
@@ -576,9 +578,11 @@ void tcp_write_timer_handler(struct sock *sk)
 	sk_mem_reclaim(sk);
 }
 
-static void tcp_write_timer(unsigned long data)
+static void tcp_write_timer(struct timer_list *t)
 {
-	struct sock *sk = (struct sock *)data;
+	struct inet_connection_sock *icsk =
+			from_timer(icsk, t, icsk_retransmit_timer);
+	struct sock *sk = &icsk->icsk_inet.sk;
 
 	bh_lock_sock(sk);
 	if (!sock_owned_by_user(sk)) {
@@ -613,9 +617,9 @@ void tcp_set_keepalive(struct sock *sk, int val)
 EXPORT_SYMBOL_GPL(tcp_set_keepalive);
 
 
-static void tcp_keepalive_timer (unsigned long data)
+static void tcp_keepalive_timer (struct timer_list *t)
 {
-	struct sock *sk = (struct sock *) data;
+	struct sock *sk = from_timer(sk, t, sk_timer);
 	struct inet_connection_sock *icsk = inet_csk(sk);
 	struct tcp_sock *tp = tcp_sk(sk);
 	u32 elapsed;