ipv4: Namespaceify tcp_tw_recycle and tcp_max_tw_buckets knob

Different namespace application might require fast recycling
TIME-WAIT sockets independently of the host.

Signed-off-by: Haishuang Yan <yanhaishuang@cmss.chinamobile.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/ipv6/tcp_ipv6.c b/net/ipv6/tcp_ipv6.c
index 73bc8fc6..a4cdf6a 100644
--- a/net/ipv6/tcp_ipv6.c
+++ b/net/ipv6/tcp_ipv6.c
@@ -123,6 +123,7 @@ static int tcp_v6_connect(struct sock *sk, struct sockaddr *uaddr,
 	struct dst_entry *dst;
 	int addr_type;
 	int err;
+	struct inet_timewait_death_row *tcp_death_row = &sock_net(sk)->ipv4.tcp_death_row;
 
 	if (addr_len < SIN6_LEN_RFC2133)
 		return -EINVAL;
@@ -258,7 +259,7 @@ static int tcp_v6_connect(struct sock *sk, struct sockaddr *uaddr,
 	sk->sk_gso_type = SKB_GSO_TCPV6;
 	ip6_dst_store(sk, dst, NULL, NULL);
 
-	if (tcp_death_row.sysctl_tw_recycle &&
+	if (tcp_death_row->sysctl_tw_recycle &&
 	    !tp->rx_opt.ts_recent_stamp &&
 	    ipv6_addr_equal(&fl6.daddr, &sk->sk_v6_daddr))
 		tcp_fetch_timewait_stamp(sk, dst);
@@ -273,7 +274,7 @@ static int tcp_v6_connect(struct sock *sk, struct sockaddr *uaddr,
 	inet->inet_dport = usin->sin6_port;
 
 	tcp_set_state(sk, TCP_SYN_SENT);
-	err = inet6_hash_connect(&tcp_death_row, sk);
+	err = inet6_hash_connect(tcp_death_row, sk);
 	if (err)
 		goto late_failure;
 
@@ -1948,7 +1949,7 @@ static void __net_exit tcpv6_net_exit(struct net *net)
 
 static void __net_exit tcpv6_net_exit_batch(struct list_head *net_exit_list)
 {
-	inet_twsk_purge(&tcp_hashinfo, &tcp_death_row, AF_INET6);
+	inet_twsk_purge(&tcp_hashinfo, AF_INET6);
 }
 
 static struct pernet_operations tcpv6_net_ops = {