netfilter: pass 'nf_hook_ops' instead of 'list_head' to nf_iterate()

Since 'list_for_each_continue_rcu' has already been replaced by
'list_for_each_entry_continue_rcu', pass 'list_head' to nf_iterate() as a
parameter can not benefit us any more.

This patch will replace 'list_head' with 'nf_hook_ops' as the parameter of
nf_iterate() to save code.

Signed-off-by: Michael Wang <wangyun@linux.vnet.ibm.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
diff --git a/net/netfilter/nf_queue.c b/net/netfilter/nf_queue.c
index ce60cf0..29fe102 100644
--- a/net/netfilter/nf_queue.c
+++ b/net/netfilter/nf_queue.c
@@ -287,7 +287,7 @@
 void nf_reinject(struct nf_queue_entry *entry, unsigned int verdict)
 {
 	struct sk_buff *skb = entry->skb;
-	struct list_head *elem = &entry->elem->list;
+	struct nf_hook_ops *elem = entry->elem;
 	const struct nf_afinfo *afinfo;
 	int err;
 
@@ -297,7 +297,7 @@
 
 	/* Continue traversal iff userspace said ok... */
 	if (verdict == NF_REPEAT) {
-		elem = elem->prev;
+		elem = list_entry(elem->list.prev, struct nf_hook_ops, list);
 		verdict = NF_ACCEPT;
 	}
 
@@ -323,7 +323,7 @@
 		local_bh_enable();
 		break;
 	case NF_QUEUE:
-		err = __nf_queue(skb, elem, entry->pf, entry->hook,
+		err = __nf_queue(skb, &elem->list, entry->pf, entry->hook,
 				 entry->indev, entry->outdev, entry->okfn,
 				 verdict >> NF_VERDICT_QBITS);
 		if (err < 0) {