netpoll: prepare for ipv6

This patch adjusts some struct and functions, to prepare
for supporting IPv6.

Cc: David S. Miller <davem@davemloft.net>
Signed-off-by: Cong Wang <amwang@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/netconsole.c

@@ -269,12 +269,14 @@ static ssize_t show_remote_port(struct netconsole_target *nt, char *buf)
 
 static ssize_t show_local_ip(struct netconsole_target *nt, char *buf)
 {
-	return snprintf(buf, PAGE_SIZE, "%pI4\n", &nt->np.local_ip);
+	if (!nt->np.ipv6)
+		return snprintf(buf, PAGE_SIZE, "%pI4\n", &nt->np.local_ip);
 }
 
 static ssize_t show_remote_ip(struct netconsole_target *nt, char *buf)
 {
-	return snprintf(buf, PAGE_SIZE, "%pI4\n", &nt->np.remote_ip);
+	if (!nt->np.ipv6)
+		return snprintf(buf, PAGE_SIZE, "%pI4\n", &nt->np.remote_ip);
 }
 
 static ssize_t show_local_mac(struct netconsole_target *nt, char *buf)
@@ -410,7 +412,8 @@ static ssize_t store_local_ip(struct netconsole_target *nt,
 		return -EINVAL;
 	}
 
-	nt->np.local_ip = in_aton(buf);
+	if (!strnchr(buf, count, ':'))
+		nt->np.local_ip.ip = in_aton(buf);
 
 	return strnlen(buf, count);
 }
@@ -426,7 +429,8 @@ static ssize_t store_remote_ip(struct netconsole_target *nt,
 		return -EINVAL;
 	}
 
-	nt->np.remote_ip = in_aton(buf);
+	if (!strnchr(buf, count, ':'))
+		nt->np.remote_ip.ip = in_aton(buf);
 
 	return strnlen(buf, count);
 }

include/linux/netpoll.h

@@ -12,13 +12,22 @@
 #include <linux/rcupdate.h>
 #include <linux/list.h>
 
+union inet_addr {
+	__u32		all[4];
+	__be32		ip;
+	__be32		ip6[4];
+	struct in_addr	in;
+	struct in6_addr	in6;
+};
+
 struct netpoll {
 	struct net_device *dev;
 	char dev_name[IFNAMSIZ];
 	const char *name;
 	void (*rx_hook)(struct netpoll *, int, char *, int);
 
-	__be32 local_ip, remote_ip;
+	union inet_addr local_ip, remote_ip;
+	bool ipv6;
 	u16 local_port, remote_port;
 	u8 remote_mac[ETH_ALEN];
 
@@ -33,7 +42,7 @@ struct netpoll_info {
 	spinlock_t rx_lock;
 	struct list_head rx_np; /* netpolls that registered an rx_hook */
 
-	struct sk_buff_head arp_tx; /* list of arp requests to reply to */
+	struct sk_buff_head neigh_tx; /* list of neigh requests to reply to */
 	struct sk_buff_head txq;
 
 	struct delayed_work tx_work;