net: dccp: convert tasklets to use new tasklet_setup() API

In preparation for unconditionally passing the
struct tasklet_struct pointer to all tasklet
callbacks, switch to using the new tasklet_setup()
and from_tasklet() to pass the tasklet pointer explicitly.
Signed-off-by: Romain Perier <romain.perier@gmail.com>
Signed-off-by: Allen Pais <apais@linux.microsoft.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

net/dccp/timer.c

@@ -215,13 +215,14 @@ static void dccp_delack_timer(struct timer_list *t)
 
 /**
  * dccp_write_xmitlet  -  Workhorse for CCID packet dequeueing interface
- * @data: Socket to act on
+ * @t: pointer to the tasklet associated with this handler
  *
  * See the comments above %ccid_dequeueing_decision for supported modes.
  */
-static void dccp_write_xmitlet(unsigned long data)
+static void dccp_write_xmitlet(struct tasklet_struct *t)
 {
-	struct sock *sk = (struct sock *)data;
+	struct dccp_sock *dp = from_tasklet(dp, t, dccps_xmitlet);
+	struct sock *sk = &dp->dccps_inet_connection.icsk_inet.sk;
 
 	bh_lock_sock(sk);
 	if (sock_owned_by_user(sk))
@@ -235,16 +236,15 @@ static void dccp_write_xmitlet(unsigned long data)
 static void dccp_write_xmit_timer(struct timer_list *t)
 {
 	struct dccp_sock *dp = from_timer(dp, t, dccps_xmit_timer);
-	struct sock *sk = &dp->dccps_inet_connection.icsk_inet.sk;
 
-	dccp_write_xmitlet((unsigned long)sk);
+	dccp_write_xmitlet(&dp->dccps_xmitlet);
 }
 
 void dccp_init_xmit_timers(struct sock *sk)
 {
 	struct dccp_sock *dp = dccp_sk(sk);
 
-	tasklet_init(&dp->dccps_xmitlet, dccp_write_xmitlet, (unsigned long)sk);
+	tasklet_setup(&dp->dccps_xmitlet, dccp_write_xmitlet);
 	timer_setup(&dp->dccps_xmit_timer, dccp_write_xmit_timer, 0);
 	inet_csk_init_xmit_timers(sk, &dccp_write_timer, &dccp_delack_timer,
 				  &dccp_keepalive_timer);