xfrm: 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()
helper to pass the timer pointer explicitly.

Cc: Steffen Klassert <steffen.klassert@secunet.com>
Cc: Herbert Xu <herbert@gondor.apana.org.au>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: netdev@vger.kernel.org
Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/xfrm/xfrm_policy.c b/net/xfrm/xfrm_policy.c
index f062539..4838329 100644
--- a/net/xfrm/xfrm_policy.c
+++ b/net/xfrm/xfrm_policy.c
@@ -57,7 +57,7 @@
 static void xfrm_init_pmtu(struct dst_entry *dst);
 static int stale_bundle(struct dst_entry *dst);
 static int xfrm_bundle_ok(struct xfrm_dst *xdst);
-static void xfrm_policy_queue_process(unsigned long arg);
+static void xfrm_policy_queue_process(struct timer_list *t);
 
 static void __xfrm_policy_link(struct xfrm_policy *pol, int dir);
 static struct xfrm_policy *__xfrm_policy_unlink(struct xfrm_policy *pol,
@@ -179,9 +179,9 @@
 		return secs*HZ;
 }
 
-static void xfrm_policy_timer(unsigned long data)
+static void xfrm_policy_timer(struct timer_list *t)
 {
-	struct xfrm_policy *xp = (struct xfrm_policy *)data;
+	struct xfrm_policy *xp = from_timer(xp, t, timer);
 	unsigned long now = get_seconds();
 	long next = LONG_MAX;
 	int warn = 0;
@@ -267,10 +267,9 @@
 		rwlock_init(&policy->lock);
 		refcount_set(&policy->refcnt, 1);
 		skb_queue_head_init(&policy->polq.hold_queue);
-		setup_timer(&policy->timer, xfrm_policy_timer,
-				(unsigned long)policy);
-		setup_timer(&policy->polq.hold_timer, xfrm_policy_queue_process,
-			    (unsigned long)policy);
+		timer_setup(&policy->timer, xfrm_policy_timer, 0);
+		timer_setup(&policy->polq.hold_timer,
+			    xfrm_policy_queue_process, 0);
 	}
 	return policy;
 }
@@ -1852,12 +1851,12 @@
 	return xdst;
 }
 
-static void xfrm_policy_queue_process(unsigned long arg)
+static void xfrm_policy_queue_process(struct timer_list *t)
 {
 	struct sk_buff *skb;
 	struct sock *sk;
 	struct dst_entry *dst;
-	struct xfrm_policy *pol = (struct xfrm_policy *)arg;
+	struct xfrm_policy *pol = from_timer(pol, t, polq.hold_timer);
 	struct net *net = xp_net(pol);
 	struct xfrm_policy_queue *pq = &pol->polq;
 	struct flowi fl;