[IPV4] SNMP: Move some statistic bits to net/ipv4/proc.c.

This also fixes memory leak in error path.
Signed-off-by: YOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

include/net/ip.h

@@ -166,6 +166,9 @@ DECLARE_SNMP_STAT(struct linux_mib, net_statistics);
 #define NET_ADD_STATS_BH(field, adnd)	SNMP_ADD_STATS_BH(net_statistics, field, adnd)
 #define NET_ADD_STATS_USER(field, adnd)	SNMP_ADD_STATS_USER(net_statistics, field, adnd)
 
+extern int snmp_mib_init(void *ptr[2], size_t mibsize, size_t mibalign);
+extern void snmp_mib_free(void *ptr[2]);
+
 extern int sysctl_local_port_range[2];
 extern int sysctl_ip_default_ttl;
 extern int sysctl_ip_nonlocal_bind;

net/ipv4/af_inet.c

@@ -1245,28 +1245,47 @@ static struct net_protocol icmp_protocol = {
 
 static int __init init_ipv4_mibs(void)
 {
-	net_statistics[0] = alloc_percpu(struct linux_mib);
-	net_statistics[1] = alloc_percpu(struct linux_mib);
-	ip_statistics[0] = alloc_percpu(struct ipstats_mib);
-	ip_statistics[1] = alloc_percpu(struct ipstats_mib);
-	icmp_statistics[0] = alloc_percpu(struct icmp_mib);
-	icmp_statistics[1] = alloc_percpu(struct icmp_mib);
-	tcp_statistics[0] = alloc_percpu(struct tcp_mib);
-	tcp_statistics[1] = alloc_percpu(struct tcp_mib);
-	udp_statistics[0] = alloc_percpu(struct udp_mib);
-	udp_statistics[1] = alloc_percpu(struct udp_mib);
-	udplite_statistics[0] = alloc_percpu(struct udp_mib);
-	udplite_statistics[1] = alloc_percpu(struct udp_mib);
-	if (!
-	    (net_statistics[0] && net_statistics[1] && ip_statistics[0]
-	     && ip_statistics[1] && tcp_statistics[0] && tcp_statistics[1]
-	     && udp_statistics[0] && udp_statistics[1]
-	     && udplite_statistics[0] && udplite_statistics[1]             ) )
-		return -ENOMEM;
-
-	(void) tcp_mib_init();
+	if (snmp_mib_init((void **)net_statistics,
+			  sizeof(struct linux_mib),
+			  __alignof__(struct linux_mib)) < 0)
+		goto err_net_mib;
+	if (snmp_mib_init((void **)ip_statistics,
+			  sizeof(struct ipstats_mib),
+			  __alignof__(struct ipstats_mib)) < 0)
+		goto err_ip_mib;
+	if (snmp_mib_init((void **)icmp_statistics,
+			  sizeof(struct icmp_mib),
+			  __alignof__(struct icmp_mib)) < 0)
+		goto err_icmp_mib;
+	if (snmp_mib_init((void **)tcp_statistics,
+			  sizeof(struct tcp_mib),
+			  __alignof__(struct tcp_mib)) < 0)
+		goto err_tcp_mib;
+	if (snmp_mib_init((void **)udp_statistics,
+			  sizeof(struct udp_mib),
+			  __alignof__(struct udp_mib)) < 0)
+		goto err_udp_mib;
+	if (snmp_mib_init((void **)udplite_statistics,
+			  sizeof(struct udp_mib),
+			  __alignof__(struct udp_mib)) < 0)
+		goto err_udplite_mib;
+
+	tcp_mib_init();
 
 	return 0;
+
+err_udplite_mib:
+	snmp_mib_free((void **)udp_statistics);
+err_udp_mib:
+	snmp_mib_free((void **)tcp_statistics);
+err_tcp_mib:
+	snmp_mib_free((void **)icmp_statistics);
+err_icmp_mib:
+	snmp_mib_free((void **)ip_statistics);
+err_ip_mib:
+	snmp_mib_free((void **)net_statistics);
+err_net_mib:
+	return -ENOMEM;
 }
 
 static int ipv4_proc_init(void);

net/ipv4/proc.c

@@ -391,3 +391,28 @@ int __init ip_misc_proc_init(void)
 	goto out;
 }
 
+int snmp_mib_init(void *ptr[2], size_t mibsize, size_t mibalign)
+{
+	BUG_ON(ptr == NULL);
+	ptr[0] = __alloc_percpu(mibsize);
+	if (!ptr[0])
+		goto err0;
+	ptr[1] = __alloc_percpu(mibsize);
+	if (!ptr[1])
+		goto err1;
+	return 0;
+err1:
+	free_percpu(ptr[0]);
+	ptr[0] = NULL;
+err0:
+	return -ENOMEM;
+}
+
+void snmp_mib_free(void *ptr[2])
+{
+	BUG_ON(ptr == NULL);
+	free_percpu(ptr[0]);
+	free_percpu(ptr[1]);
+	ptr[0] = ptr[1] = NULL;
+}
+