[NET] NETNS: Omit sock->sk_net without CONFIG_NET_NS.

Introduce per-sock inlines: sock_net(), sock_net_set()
and per-inet_timewait_sock inlines: twsk_net(), twsk_net_set().
Without CONFIG_NET_NS, no namespace other than &init_net exists.
Let's explicitly define them to help compiler optimizations.

Signed-off-by: YOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org>

69 files changed, 253 insertions, 215 deletions

diff --git a/include/linux/ipv6.h b/include/linux/ipv6.h
index c9ba0da16ce9..b90d3d461d4e 100644
--- a/include/linux/ipv6.h
+++ b/include/linux/ipv6.h
@@ -481,7 +481,7 @@ static inline struct raw6_sock *raw6_sk(const struct sock *sk)
 #endif /* defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE) */
 
 #define INET6_MATCH(__sk, __net, __hash, __saddr, __daddr, __ports, __dif)\
-	(((__sk)->sk_hash == (__hash)) && ((__sk)->sk_net == (__net))	&& \
+	(((__sk)->sk_hash == (__hash)) && sock_net((__sk)) == (__net)	&& \
 	 ((*((__portpair *)&(inet_sk(__sk)->dport))) == (__ports))  	&& \
 	 ((__sk)->sk_family		== AF_INET6)		&& \
 	 ipv6_addr_equal(&inet6_sk(__sk)->daddr, (__saddr))	&& \
@@ -489,7 +489,7 @@ static inline struct raw6_sock *raw6_sk(const struct sock *sk)
 	 (!((__sk)->sk_bound_dev_if) || ((__sk)->sk_bound_dev_if == (__dif))))
 
 #define INET6_TW_MATCH(__sk, __net, __hash, __saddr, __daddr, __ports, __dif) \
-	(((__sk)->sk_hash == (__hash)) && ((__sk)->sk_net == (__net))	&& \
+	(((__sk)->sk_hash == (__hash)) && sock_net((__sk)) == (__net)	&& \
 	 (*((__portpair *)&(inet_twsk(__sk)->tw_dport)) == (__ports))	&& \
 	 ((__sk)->sk_family	       == PF_INET6)			&& \
 	 (ipv6_addr_equal(&inet6_twsk(__sk)->tw_v6_daddr, (__saddr)))	&& \
diff --git a/include/net/inet_hashtables.h b/include/net/inet_hashtables.h
index d99c1ba2ece0..5525227c5e92 100644
--- a/include/net/inet_hashtables.h
+++ b/include/net/inet_hashtables.h
@@ -314,25 +314,25 @@ typedef __u64 __bitwise __addrpair;
 				   ((__force __u64)(__be32)(__saddr)));
 #endif /* __BIG_ENDIAN */
 #define INET_MATCH(__sk, __net, __hash, __cookie, __saddr, __daddr, __ports, __dif)\
-	(((__sk)->sk_hash == (__hash)) && ((__sk)->sk_net == (__net))	&&	\
+	(((__sk)->sk_hash == (__hash)) && sock_net((__sk)) == (__net)	&&	\
 	 ((*((__addrpair *)&(inet_sk(__sk)->daddr))) == (__cookie))	&&	\
 	 ((*((__portpair *)&(inet_sk(__sk)->dport))) == (__ports))	&&	\
 	 (!((__sk)->sk_bound_dev_if) || ((__sk)->sk_bound_dev_if == (__dif))))
 #define INET_TW_MATCH(__sk, __net, __hash, __cookie, __saddr, __daddr, __ports, __dif)\
-	(((__sk)->sk_hash == (__hash)) && ((__sk)->sk_net == (__net))	&&	\
+	(((__sk)->sk_hash == (__hash)) && sock_net((__sk)) == (__net)	&&	\
 	 ((*((__addrpair *)&(inet_twsk(__sk)->tw_daddr))) == (__cookie)) &&	\
 	 ((*((__portpair *)&(inet_twsk(__sk)->tw_dport))) == (__ports)) &&	\
 	 (!((__sk)->sk_bound_dev_if) || ((__sk)->sk_bound_dev_if == (__dif))))
 #else /* 32-bit arch */
 #define INET_ADDR_COOKIE(__name, __saddr, __daddr)
 #define INET_MATCH(__sk, __net, __hash, __cookie, __saddr, __daddr, __ports, __dif)	\
-	(((__sk)->sk_hash == (__hash)) && ((__sk)->sk_net == (__net))	&&	\
+	(((__sk)->sk_hash == (__hash)) && sock_net((__sk)) == (__net)	&&	\
 	 (inet_sk(__sk)->daddr		== (__saddr))		&&	\
 	 (inet_sk(__sk)->rcv_saddr	== (__daddr))		&&	\
 	 ((*((__portpair *)&(inet_sk(__sk)->dport))) == (__ports))	&&	\
 	 (!((__sk)->sk_bound_dev_if) || ((__sk)->sk_bound_dev_if == (__dif))))
 #define INET_TW_MATCH(__sk, __net, __hash,__cookie, __saddr, __daddr, __ports, __dif)	\
-	(((__sk)->sk_hash == (__hash)) && ((__sk)->sk_net == (__net))	&&	\
+	(((__sk)->sk_hash == (__hash)) && sock_net((__sk)) == (__net)	&&	\
 	 (inet_twsk(__sk)->tw_daddr	== (__saddr))		&&	\
 	 (inet_twsk(__sk)->tw_rcv_saddr	== (__daddr))		&&	\
 	 ((*((__portpair *)&(inet_twsk(__sk)->tw_dport))) == (__ports)) &&	\
diff --git a/include/net/inet_timewait_sock.h b/include/net/inet_timewait_sock.h
index 296547bfb0b7..07fe0d1a4f03 100644
--- a/include/net/inet_timewait_sock.h
+++ b/include/net/inet_timewait_sock.h
@@ -207,4 +207,22 @@ extern void inet_twsk_schedule(struct inet_timewait_sock *tw,
 			       const int timeo, const int timewait_len);
 extern void inet_twsk_deschedule(struct inet_timewait_sock *tw,
 				 struct inet_timewait_death_row *twdr);
+
+static inline
+struct net *twsk_net(const struct inet_timewait_sock *twsk)
+{
+#ifdef CONFIG_NET_NS
+	return twsk->tw_net;
+#else
+	return &init_net;
+#endif
+}
+
+static inline
+void twsk_net_set(struct inet_timewait_sock *twsk, const struct net *net)
+{
+#ifdef CONFIG_NET_NS
+	twsk->tw_net = net;
+#endif
+}
 #endif	/* _INET_TIMEWAIT_SOCK_ */
diff --git a/include/net/route.h b/include/net/route.h
index 28dba925663c..c6338802e8f1 100644
--- a/include/net/route.h
+++ b/include/net/route.h
@@ -160,7 +160,7 @@ static inline int ip_route_connect(struct rtable **rp, __be32 dst,
 					 .dport = dport } } };
 
 	int err;
-	struct net *net = sk->sk_net;
+	struct net *net = sock_net(sk);
 	if (!dst || !src) {
 		err = __ip_route_output_key(net, rp, &fl);
 		if (err)
@@ -188,7 +188,7 @@ static inline int ip_route_newports(struct rtable **rp, u8 protocol,
 		ip_rt_put(*rp);
 		*rp = NULL;
 		security_sk_classify_flow(sk, &fl);
-		return ip_route_output_flow(sk->sk_net, rp, &fl, sk, 0);
+		return ip_route_output_flow(sock_net(sk), rp, &fl, sk, 0);
 	}
 	return 0;
 }
diff --git a/include/net/sock.h b/include/net/sock.h
index b433b1ed203d..7e0d4a0c4d12 100644
--- a/include/net/sock.h
+++ b/include/net/sock.h
@@ -126,7 +126,9 @@ struct sock_common {
 	atomic_t		skc_refcnt;
 	unsigned int		skc_hash;
 	struct proto		*skc_prot;
+#ifdef CONFIG_NET_NS
 	struct net	 	*skc_net;
+#endif
 };
 
 /**
@@ -1345,6 +1347,24 @@ static inline void sk_eat_skb(struct sock *sk, struct sk_buff *skb, int copied_e
 }
 #endif
 
+static inline
+struct net *sock_net(const struct sock *sk)
+{
+#ifdef CONFIG_NET_NS
+	return sk->sk_net;
+#else
+	return &init_net;
+#endif
+}
+
+static inline
+void sock_net_set(struct sock *sk, const struct net *net)
+{
+#ifdef CONFIG_NET_NS
+	sk->sk_net = net;
+#endif
+}
+
 /*
  * Kernel sockets, f.e. rtnl or icmp_socket, are a part of a namespace.
  * They should not hold a referrence to a namespace in order to allow
@@ -1353,8 +1373,8 @@ static inline void sk_eat_skb(struct sock *sk, struct sk_buff *skb, int copied_e
  */
 static inline void sk_change_net(struct sock *sk, struct net *net)
 {
-	put_net(sk->sk_net);
-	sk->sk_net = net;
+	put_net(sock_net(sk));
+	sock_net_set(sk, net);
 }
 
 extern void sock_enable_timestamp(struct sock *sk);
diff --git a/net/atm/svc.c b/net/atm/svc.c
index daf9a48a7db0..de1e4f2f3a43 100644
--- a/net/atm/svc.c
+++ b/net/atm/svc.c
@@ -326,7 +326,7 @@ static int svc_accept(struct socket *sock,struct socket *newsock,int flags)
 
 	lock_sock(sk);
 
-	error = svc_create(sk->sk_net, newsock,0);
+	error = svc_create(sock_net(sk), newsock,0);
 	if (error)
 		goto out;
 
diff --git a/net/ax25/af_ax25.c b/net/ax25/af_ax25.c
index ee9dd83e7561..2712544cf0ca 100644
--- a/net/ax25/af_ax25.c
+++ b/net/ax25/af_ax25.c
@@ -869,7 +869,7 @@ struct sock *ax25_make_new(struct sock *osk, struct ax25_dev *ax25_dev)
 	struct sock *sk;
 	ax25_cb *ax25, *oax25;
 
-	sk = sk_alloc(osk->sk_net, PF_AX25, GFP_ATOMIC,	osk->sk_prot);
+	sk = sk_alloc(sock_net(osk), PF_AX25, GFP_ATOMIC,	osk->sk_prot);
 	if (sk == NULL)
 		return NULL;
 
diff --git a/net/bluetooth/l2cap.c b/net/bluetooth/l2cap.c
index 34f8bf98bc05..6b995ac832f5 100644
--- a/net/bluetooth/l2cap.c
+++ b/net/bluetooth/l2cap.c
@@ -1499,7 +1499,7 @@ static inline int l2cap_connect_req(struct l2cap_conn *conn, struct l2cap_cmd_hd
 		goto response;
 	}
 
-	sk = l2cap_sock_alloc(parent->sk_net, NULL, BTPROTO_L2CAP, GFP_ATOMIC);
+	sk = l2cap_sock_alloc(sock_net(parent), NULL, BTPROTO_L2CAP, GFP_ATOMIC);
 	if (!sk)
 		goto response;
 
diff --git a/net/bluetooth/rfcomm/sock.c b/net/bluetooth/rfcomm/sock.c
index c46d51035e77..c103fa02893b 100644
--- a/net/bluetooth/rfcomm/sock.c
+++ b/net/bluetooth/rfcomm/sock.c
@@ -868,7 +868,7 @@ int rfcomm_connect_ind(struct rfcomm_session *s, u8 channel, struct rfcomm_dlc *
 		goto done;
 	}
 
-	sk = rfcomm_sock_alloc(parent->sk_net, NULL, BTPROTO_RFCOMM, GFP_ATOMIC);
+	sk = rfcomm_sock_alloc(sock_net(parent), NULL, BTPROTO_RFCOMM, GFP_ATOMIC);
 	if (!sk)
 		goto done;
 
diff --git a/net/bluetooth/sco.c b/net/bluetooth/sco.c
index b91d3c81a73c..2a5953b4405d 100644
--- a/net/bluetooth/sco.c
+++ b/net/bluetooth/sco.c
@@ -803,7 +803,7 @@ static void sco_conn_ready(struct sco_conn *conn)
 
 		bh_lock_sock(parent);
 
-		sk = sco_sock_alloc(parent->sk_net, NULL, BTPROTO_SCO, GFP_ATOMIC);
+		sk = sco_sock_alloc(sock_net(parent), NULL, BTPROTO_SCO, GFP_ATOMIC);
 		if (!sk) {
 			bh_unlock_sock(parent);
 			goto done;
diff --git a/net/bridge/br_netlink.c b/net/bridge/br_netlink.c
index f5d69336d97b..f155e6ce8a21 100644
--- a/net/bridge/br_netlink.c
+++ b/net/bridge/br_netlink.c
@@ -108,7 +108,7 @@ errout:
  */
 static int br_dump_ifinfo(struct sk_buff *skb, struct netlink_callback *cb)
 {
-	struct net *net = skb->sk->sk_net;
+	struct net *net = sock_net(skb->sk);
 	struct net_device *dev;
 	int idx;
 
@@ -140,7 +140,7 @@ skip:
  */
 static int br_rtm_setlink(struct sk_buff *skb,  struct nlmsghdr *nlh, void *arg)
 {
-	struct net *net = skb->sk->sk_net;
+	struct net *net = sock_net(skb->sk);
 	struct ifinfomsg *ifm;
 	struct nlattr *protinfo;
 	struct net_device *dev;
diff --git a/net/core/fib_rules.c b/net/core/fib_rules.c
index 942be93a2eb0..540c07283e31 100644
--- a/net/core/fib_rules.c
+++ b/net/core/fib_rules.c
@@ -214,7 +214,7 @@ errout:
 
 static int fib_nl_newrule(struct sk_buff *skb, struct nlmsghdr* nlh, void *arg)
 {
-	struct net *net = skb->sk->sk_net;
+	struct net *net = sock_net(skb->sk);
 	struct fib_rule_hdr *frh = nlmsg_data(nlh);
 	struct fib_rules_ops *ops = NULL;
 	struct fib_rule *rule, *r, *last = NULL;
@@ -352,7 +352,7 @@ errout:
 
 static int fib_nl_delrule(struct sk_buff *skb, struct nlmsghdr* nlh, void *arg)
 {
-	struct net *net = skb->sk->sk_net;
+	struct net *net = sock_net(skb->sk);
 	struct fib_rule_hdr *frh = nlmsg_data(nlh);
 	struct fib_rules_ops *ops = NULL;
 	struct fib_rule *rule, *tmp;
@@ -534,7 +534,7 @@ skip:
 
 static int fib_nl_dumprule(struct sk_buff *skb, struct netlink_callback *cb)
 {
-	struct net *net = skb->sk->sk_net;
+	struct net *net = sock_net(skb->sk);
 	struct fib_rules_ops *ops;
 	int idx = 0, family;
 
diff --git a/net/core/neighbour.c b/net/core/neighbour.c
index c978bd1cd659..065fbac7ecd3 100644
--- a/net/core/neighbour.c
+++ b/net/core/neighbour.c
@@ -1478,7 +1478,7 @@ int neigh_table_clear(struct neigh_table *tbl)
 
 static int neigh_delete(struct sk_buff *skb, struct nlmsghdr *nlh, void *arg)
 {
-	struct net *net = skb->sk->sk_net;
+	struct net *net = sock_net(skb->sk);
 	struct ndmsg *ndm;
 	struct nlattr *dst_attr;
 	struct neigh_table *tbl;
@@ -1544,7 +1544,7 @@ out:
 
 static int neigh_add(struct sk_buff *skb, struct nlmsghdr *nlh, void *arg)
 {
-	struct net *net = skb->sk->sk_net;
+	struct net *net = sock_net(skb->sk);
 	struct ndmsg *ndm;
 	struct nlattr *tb[NDA_MAX+1];
 	struct neigh_table *tbl;
@@ -1812,7 +1812,7 @@ static const struct nla_policy nl_ntbl_parm_policy[NDTPA_MAX+1] = {
 
 static int neightbl_set(struct sk_buff *skb, struct nlmsghdr *nlh, void *arg)
 {
-	struct net *net = skb->sk->sk_net;
+	struct net *net = sock_net(skb->sk);
 	struct neigh_table *tbl;
 	struct ndtmsg *ndtmsg;
 	struct nlattr *tb[NDTA_MAX+1];
@@ -1937,7 +1937,7 @@ errout:
 
 static int neightbl_dump_info(struct sk_buff *skb, struct netlink_callback *cb)
 {
-	struct net *net = skb->sk->sk_net;
+	struct net *net = sock_net(skb->sk);
 	int family, tidx, nidx = 0;
 	int tbl_skip = cb->args[0];
 	int neigh_skip = cb->args[1];
@@ -2037,7 +2037,7 @@ static void neigh_update_notify(struct neighbour *neigh)
 static int neigh_dump_table(struct neigh_table *tbl, struct sk_buff *skb,
 			    struct netlink_callback *cb)
 {
-	struct net * net = skb->sk->sk_net;
+	struct net * net = sock_net(skb->sk);
 	struct neighbour *n;
 	int rc, h, s_h = cb->args[1];
 	int idx, s_idx = idx = cb->args[2];
diff --git a/net/core/rtnetlink.c b/net/core/rtnetlink.c
index 09250a0800f6..da99ac0871bf 100644
--- a/net/core/rtnetlink.c
+++ b/net/core/rtnetlink.c
@@ -662,7 +662,7 @@ nla_put_failure:
 
 static int rtnl_dump_ifinfo(struct sk_buff *skb, struct netlink_callback *cb)
 {
-	struct net *net = skb->sk->sk_net;
+	struct net *net = sock_net(skb->sk);
 	int idx;
 	int s_idx = cb->args[0];
 	struct net_device *dev;
@@ -879,7 +879,7 @@ errout:
 
 static int rtnl_setlink(struct sk_buff *skb, struct nlmsghdr *nlh, void *arg)
 {
-	struct net *net = skb->sk->sk_net;
+	struct net *net = sock_net(skb->sk);
 	struct ifinfomsg *ifm;
 	struct net_device *dev;
 	int err;
@@ -921,7 +921,7 @@ errout:
 
 static int rtnl_dellink(struct sk_buff *skb, struct nlmsghdr *nlh, void *arg)
 {
-	struct net *net = skb->sk->sk_net;
+	struct net *net = sock_net(skb->sk);
 	const struct rtnl_link_ops *ops;
 	struct net_device *dev;
 	struct ifinfomsg *ifm;
@@ -1000,7 +1000,7 @@ err:
 
 static int rtnl_newlink(struct sk_buff *skb, struct nlmsghdr *nlh, void *arg)
 {
-	struct net *net = skb->sk->sk_net;
+	struct net *net = sock_net(skb->sk);
 	const struct rtnl_link_ops *ops;
 	struct net_device *dev;
 	struct ifinfomsg *ifm;
@@ -1132,7 +1132,7 @@ replay:
 
 static int rtnl_getlink(struct sk_buff *skb, struct nlmsghdr* nlh, void *arg)
 {
-	struct net *net = skb->sk->sk_net;
+	struct net *net = sock_net(skb->sk);
 	struct ifinfomsg *ifm;
 	struct nlattr *tb[IFLA_MAX+1];
 	struct net_device *dev = NULL;
@@ -1227,7 +1227,7 @@ static int rtattr_max;
 
 static int rtnetlink_rcv_msg(struct sk_buff *skb, struct nlmsghdr *nlh)
 {
-	struct net *net = skb->sk->sk_net;
+	struct net *net = sock_net(skb->sk);
 	rtnl_doit_func doit;
 	int sz_idx, kind;
 	int min_len;
diff --git a/net/core/sock.c b/net/core/sock.c
index b1a6ed4d33c1..3ee95060dbd0 100644
--- a/net/core/sock.c
+++ b/net/core/sock.c
@@ -372,7 +372,7 @@ static int sock_bindtodevice(struct sock *sk, char __user *optval, int optlen)
 {
 	int ret = -ENOPROTOOPT;
 #ifdef CONFIG_NETDEVICES
-	struct net *net = sk->sk_net;
+	struct net *net = sock_net(sk);
 	char devname[IFNAMSIZ];
 	int index;
 
@@ -958,7 +958,7 @@ struct sock *sk_alloc(struct net *net, int family, gfp_t priority,
 		 */
 		sk->sk_prot = sk->sk_prot_creator = prot;
 		sock_lock_init(sk);
-		sk->sk_net = get_net(net);
+		sock_net_set(sk, get_net(net));
 	}
 
 	return sk;
@@ -983,7 +983,7 @@ void sk_free(struct sock *sk)
 		printk(KERN_DEBUG "%s: optmem leakage (%d bytes) detected.\n",
 		       __func__, atomic_read(&sk->sk_omem_alloc));
 
-	put_net(sk->sk_net);
+	put_net(sock_net(sk));
 	sk_prot_free(sk->sk_prot_creator, sk);
 }
 
@@ -1001,7 +1001,7 @@ void sk_release_kernel(struct sock *sk)
 
 	sock_hold(sk);
 	sock_release(sk->sk_socket);
-	sk->sk_net = get_net(&init_net);
+	sock_net_set(sk, get_net(&init_net));
 	sock_put(sk);
 }
 EXPORT_SYMBOL(sk_release_kernel);
@@ -1017,7 +1017,7 @@ struct sock *sk_clone(const struct sock *sk, const gfp_t priority)
 		sock_copy(newsk, sk);
 
 		/* SANITY */
-		get_net(newsk->sk_net);
+		get_net(sock_net(newsk));
 		sk_node_init(&newsk->sk_node);
 		sock_lock_init(newsk);
 		bh_lock_sock(newsk);
diff --git a/net/decnet/af_decnet.c b/net/decnet/af_decnet.c
index 3554fb3d251c..fc2efe899e91 100644
--- a/net/decnet/af_decnet.c
+++ b/net/decnet/af_decnet.c
@@ -1094,7 +1094,7 @@ static int dn_accept(struct socket *sock, struct socket *newsock, int flags)
 
 	cb = DN_SKB_CB(skb);
 	sk->sk_ack_backlog--;
-	newsk = dn_alloc_sock(sk->sk_net, newsock, sk->sk_allocation);
+	newsk = dn_alloc_sock(sock_net(sk), newsock, sk->sk_allocation);
 	if (newsk == NULL) {
 		release_sock(sk);
 		kfree_skb(skb);
diff --git a/net/decnet/dn_dev.c b/net/decnet/dn_dev.c
index 1bbfce5f7a2d..2f0ac3c3eb71 100644
--- a/net/decnet/dn_dev.c
+++ b/net/decnet/dn_dev.c
@@ -625,7 +625,7 @@ static const struct nla_policy dn_ifa_policy[IFA_MAX+1] = {
 
 static int dn_nl_deladdr(struct sk_buff *skb, struct nlmsghdr *nlh, void *arg)
 {
-	struct net *net = skb->sk->sk_net;
+	struct net *net = sock_net(skb->sk);
 	struct nlattr *tb[IFA_MAX+1];
 	struct dn_dev *dn_db;
 	struct ifaddrmsg *ifm;
@@ -663,7 +663,7 @@ errout:
 
 static int dn_nl_newaddr(struct sk_buff *skb, struct nlmsghdr *nlh, void *arg)
 {
-	struct net *net = skb->sk->sk_net;
+	struct net *net = sock_net(skb->sk);
 	struct nlattr *tb[IFA_MAX+1];
 	struct net_device *dev;
 	struct dn_dev *dn_db;
@@ -779,7 +779,7 @@ errout:
 
 static int dn_nl_dump_ifaddr(struct sk_buff *skb, struct netlink_callback *cb)
 {
-	struct net *net = skb->sk->sk_net;
+	struct net *net = sock_net(skb->sk);
 	int idx, dn_idx = 0, skip_ndevs, skip_naddr;
 	struct net_device *dev;
 	struct dn_dev *dn_db;