net: add a net pointer to struct fqdir

fqdir will soon be dynamically allocated.

We need to reach the struct net pointer from fqdir,
so add it, and replace the various container_of() constructs
by direct access to the new field.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

include/net/inet_frag.h

@@ -12,6 +12,7 @@ struct fqdir {
 	int			timeout;
 	int			max_dist;
 	struct inet_frags	*f;
+	struct net		*net;
 
 	struct rhashtable       rhashtable ____cacheline_aligned_in_smp;
 
@@ -104,9 +105,11 @@ struct inet_frags {
 int inet_frags_init(struct inet_frags *);
 void inet_frags_fini(struct inet_frags *);
 
-static inline int fqdir_init(struct fqdir *fqdir, struct inet_frags *f)
+static inline int fqdir_init(struct fqdir *fqdir, struct inet_frags *f,
+			     struct net *net)
 {
 	fqdir->f = f;
+	fqdir->net = net;
 	atomic_long_set(&fqdir->mem, 0);
 	return rhashtable_init(&fqdir->rhashtable, &fqdir->f->rhash_params);
 }

net/ieee802154/6lowpan/reassembly.c

@@ -453,7 +453,7 @@ static int __net_init lowpan_frags_init_net(struct net *net)
 	ieee802154_lowpan->fqdir.low_thresh = IPV6_FRAG_LOW_THRESH;
 	ieee802154_lowpan->fqdir.timeout = IPV6_FRAG_TIMEOUT;
 
-	res = fqdir_init(&ieee802154_lowpan->fqdir, &lowpan_frags);
+	res = fqdir_init(&ieee802154_lowpan->fqdir, &lowpan_frags, net);
 	if (res < 0)
 		return res;
 	res = lowpan_frags_ns_sysctl_register(net);

net/ipv4/ip_fragment.c

@@ -82,9 +82,7 @@ static int ip_frag_reasm(struct ipq *qp, struct sk_buff *skb,
 static void ip4_frag_init(struct inet_frag_queue *q, const void *a)
 {
 	struct ipq *qp = container_of(q, struct ipq, q);
-	struct netns_ipv4 *ipv4 = container_of(q->fqdir, struct netns_ipv4,
-					       fqdir);
-	struct net *net = container_of(ipv4, struct net, ipv4);
+	struct net *net = q->fqdir->net;
 
 	const struct frag_v4_compare_key *key = a;
 
@@ -142,7 +140,7 @@ static void ip_expire(struct timer_list *t)
 	int err;
 
 	qp = container_of(frag, struct ipq, q);
-	net = container_of(qp->q.fqdir, struct net, ipv4.fqdir);
+	net = qp->q.fqdir->net;
 
 	rcu_read_lock();
 	spin_lock(&qp->q.lock);
@@ -236,12 +234,8 @@ static int ip_frag_too_far(struct ipq *qp)
 
 	rc = qp->q.fragments_tail && (end - start) > max;
 
-	if (rc) {
-		struct net *net;
-
-		net = container_of(qp->q.fqdir, struct net, ipv4.fqdir);
-		__IP_INC_STATS(net, IPSTATS_MIB_REASMFAILS);
-	}
+	if (rc)
+		__IP_INC_STATS(qp->q.fqdir->net, IPSTATS_MIB_REASMFAILS);
 
 	return rc;
 }
@@ -273,7 +267,7 @@ static int ip_frag_reinit(struct ipq *qp)
 /* Add new segment to existing queue. */
 static int ip_frag_queue(struct ipq *qp, struct sk_buff *skb)
 {
-	struct net *net = container_of(qp->q.fqdir, struct net, ipv4.fqdir);
+	struct net *net = qp->q.fqdir->net;
 	int ihl, end, flags, offset;
 	struct sk_buff *prev_tail;
 	struct net_device *dev;
@@ -399,7 +393,7 @@ static int ip_frag_queue(struct ipq *qp, struct sk_buff *skb)
 static int ip_frag_reasm(struct ipq *qp, struct sk_buff *skb,
 			 struct sk_buff *prev_tail, struct net_device *dev)
 {
-	struct net *net = container_of(qp->q.fqdir, struct net, ipv4.fqdir);
+	struct net *net = qp->q.fqdir->net;
 	struct iphdr *iph;
 	void *reasm_data;
 	int len, err;
@@ -673,7 +667,7 @@ static int __net_init ipv4_frags_init_net(struct net *net)
 
 	net->ipv4.fqdir.max_dist = 64;
 
-	res = fqdir_init(&net->ipv4.fqdir, &ip4_frags);
+	res = fqdir_init(&net->ipv4.fqdir, &ip4_frags, net);
 	if (res < 0)
 		return res;
 	res = ip4_frags_ns_ctl_register(net);

net/ipv6/netfilter/nf_conntrack_reasm.c

@@ -143,12 +143,10 @@ static void nf_ct_frag6_expire(struct timer_list *t)
 {
 	struct inet_frag_queue *frag = from_timer(frag, t, timer);
 	struct frag_queue *fq;
-	struct net *net;
 
 	fq = container_of(frag, struct frag_queue, q);
-	net = container_of(fq->q.fqdir, struct net, nf_frag.fqdir);
 
-	ip6frag_expire_frag_queue(net, fq);
+	ip6frag_expire_frag_queue(fq->q.fqdir->net, fq);
 }
 
 /* Creation primitives. */
@@ -495,7 +493,7 @@ static int nf_ct_net_init(struct net *net)
 	net->nf_frag.fqdir.low_thresh = IPV6_FRAG_LOW_THRESH;
 	net->nf_frag.fqdir.timeout = IPV6_FRAG_TIMEOUT;
 
-	res = fqdir_init(&net->nf_frag.fqdir, &nf_frags);
+	res = fqdir_init(&net->nf_frag.fqdir, &nf_frags, net);
 	if (res < 0)
 		return res;
 	res = nf_ct_frag6_sysctl_register(net);

net/ipv6/reassembly.c

@@ -76,12 +76,10 @@ static void ip6_frag_expire(struct timer_list *t)
 {
 	struct inet_frag_queue *frag = from_timer(frag, t, timer);
 	struct frag_queue *fq;
-	struct net *net;
 
 	fq = container_of(frag, struct frag_queue, q);
-	net = container_of(fq->q.fqdir, struct net, ipv6.fqdir);
 
-	ip6frag_expire_frag_queue(net, fq);
+	ip6frag_expire_frag_queue(fq->q.fqdir->net, fq);
 }
 
 static struct frag_queue *
@@ -254,7 +252,7 @@ static int ip6_frag_queue(struct frag_queue *fq, struct sk_buff *skb,
 static int ip6_frag_reasm(struct frag_queue *fq, struct sk_buff *skb,
 			  struct sk_buff *prev_tail, struct net_device *dev)
 {
-	struct net *net = container_of(fq->q.fqdir, struct net, ipv6.fqdir);
+	struct net *net = fq->q.fqdir->net;
 	unsigned int nhoff;
 	void *reasm_data;
 	int payload_len;
@@ -516,7 +514,7 @@ static int __net_init ipv6_frags_init_net(struct net *net)
 	net->ipv6.fqdir.low_thresh = IPV6_FRAG_LOW_THRESH;
 	net->ipv6.fqdir.timeout = IPV6_FRAG_TIMEOUT;
 
-	res = fqdir_init(&net->ipv6.fqdir, &ip6_frags);
+	res = fqdir_init(&net->ipv6.fqdir, &ip6_frags, net);
 	if (res < 0)
 		return res;