net: sched: 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>

include/net/pkt_sched.h

@@ -24,6 +24,11 @@ static inline void *qdisc_priv(struct Qdisc *q)
 	return &q->privdata;
 }
 
+static inline struct Qdisc *qdisc_from_priv(void *priv)
+{
+	return container_of(priv, struct Qdisc, privdata);
+}
+
 /* 
    Timer resolution MUST BE < 10% of min_schedulable_packet_size/bandwidth
    

net/sched/sch_atm.c

@@ -466,10 +466,10 @@ drop: __maybe_unused
  * non-ATM interfaces.
  */
 
-static void sch_atm_dequeue(unsigned long data)
+static void sch_atm_dequeue(struct tasklet_struct *t)
 {
-	struct Qdisc *sch = (struct Qdisc *)data;
-	struct atm_qdisc_data *p = qdisc_priv(sch);
+	struct atm_qdisc_data *p = from_tasklet(p, t, task);
+	struct Qdisc *sch = qdisc_from_priv(p);
 	struct atm_flow_data *flow;
 	struct sk_buff *skb;
 
@@ -563,7 +563,7 @@ static int atm_tc_init(struct Qdisc *sch, struct nlattr *opt,
 	if (err)
 		return err;
 
-	tasklet_init(&p->task, sch_atm_dequeue, (unsigned long)sch);
+	tasklet_setup(&p->task, sch_atm_dequeue);
 	return 0;
 }