[INET]: Consolidate xxx_frag_alloc()

Just perform the kzalloc() allocation and setup common
fields in the inet_frag_queue(). Then return the result
to the caller to initialize the rest.

The inet_frag_alloc() may return NULL, so check the 
return value before doing the container_of(). This looks 
ugly, but the xxx_frag_alloc() will be removed soon.

The xxx_expire() timer callbacks are patches, 
because the argument is now the inet_frag_queue, not 
the protocol specific queue.

Signed-off-by: Pavel Emelyanov <xemul@openvz.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/ipv6/reassembly.c b/net/ipv6/reassembly.c
index 73ea204..21913c7 100644
--- a/net/ipv6/reassembly.c
+++ b/net/ipv6/reassembly.c
@@ -171,12 +171,10 @@
 
 static inline struct frag_queue *frag_alloc_queue(void)
 {
-	struct frag_queue *fq = kzalloc(sizeof(struct frag_queue), GFP_ATOMIC);
+	struct inet_frag_queue *q;
 
-	if(!fq)
-		return NULL;
-	atomic_add(sizeof(struct frag_queue), &ip6_frags.mem);
-	return fq;
+	q = inet_frag_alloc(&ip6_frags);
+	return q ? container_of(q, struct frag_queue, q) : NULL;
 }
 
 /* Destruction primitives. */
@@ -205,9 +203,11 @@
 
 static void ip6_frag_expire(unsigned long data)
 {
-	struct frag_queue *fq = (struct frag_queue *) data;
+	struct frag_queue *fq;
 	struct net_device *dev = NULL;
 
+	fq = container_of((struct inet_frag_queue *)data, struct frag_queue, q);
+
 	spin_lock(&fq->q.lock);
 
 	if (fq->q.last_in & COMPLETE)
@@ -268,12 +268,6 @@
 	ipv6_addr_copy(&fq->saddr, src);
 	ipv6_addr_copy(&fq->daddr, dst);
 
-	init_timer(&fq->q.timer);
-	fq->q.timer.function = ip6_frag_expire;
-	fq->q.timer.data = (long) fq;
-	spin_lock_init(&fq->q.lock);
-	atomic_set(&fq->q.refcnt, 1);
-
 	return ip6_frag_intern(fq, hash);
 
 oom:
@@ -685,5 +679,6 @@
 	ip6_frags.skb_free = NULL;
 	ip6_frags.qsize = sizeof(struct frag_queue);
 	ip6_frags.equal = ip6_frag_equal;
+	ip6_frags.frag_expire = ip6_frag_expire;
 	inet_frags_init(&ip6_frags);
 }