[INFINIBAND]: IPoIB IPv6 support

Add ipv6_ib_mc_map() to convert IPv6 multicast addresses to IPoIB
hardware addresses, and add support for autoconfiguration for devices
with type ARPHRD_INFINIBAND.

The mapping for multicast addresses is described in
  http://www.ietf.org/internet-drafts/draft-ietf-ipoib-ip-over-infiniband-08.txtSigned-off-by: Nitin Hande <Nitin.Hande@Sun.Com>
Signed-off-by: Roland Dreier <roland@topspin.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

include/net/if_inet6.h

@@ -266,5 +266,20 @@ static inline void ipv6_arcnet_mc_map(const struct in6_addr *addr, char *buf)
 {
 	buf[0] = 0x00;
 }
+
+static inline void ipv6_ib_mc_map(struct in6_addr *addr, char *buf)
+{
+	buf[0]  = 0;		/* Reserved */
+	buf[1]  = 0xff;		/* Multicast QPN */
+	buf[2]  = 0xff;
+	buf[3]  = 0xff;
+	buf[4]  = 0xff;
+	buf[5]  = 0x12;		/* link local scope */
+	buf[6]  = 0x60;		/* IPv6 signature */
+	buf[7]  = 0x1b;
+	buf[8]  = 0;		/* P_Key */
+	buf[9]  = 0;
+	memcpy(buf + 10, addr->s6_addr + 6, 10);
+}
 #endif
 #endif

net/ipv6/addrconf.c

@@ -48,6 +48,7 @@
 #include <linux/netdevice.h>
 #include <linux/if_arp.h>
 #include <linux/if_arcnet.h>
+#include <linux/if_infiniband.h>
 #include <linux/route.h>
 #include <linux/inetdevice.h>
 #include <linux/init.h>
@@ -1095,6 +1096,12 @@ static int ipv6_generate_eui64(u8 *eui, struct net_device *dev)
 		memset(eui, 0, 7);
 		eui[7] = *(u8*)dev->dev_addr;
 		return 0;
+	case ARPHRD_INFINIBAND:
+		if (dev->addr_len != INFINIBAND_ALEN)
+			return -1;
+		memcpy(eui, dev->dev_addr + 12, 8);
+		eui[0] |= 2;
+		return 0;
 	}
 	return -1;
 }
@@ -1794,7 +1801,8 @@ static void addrconf_dev_config(struct net_device *dev)
 	if ((dev->type != ARPHRD_ETHER) && 
 	    (dev->type != ARPHRD_FDDI) &&
 	    (dev->type != ARPHRD_IEEE802_TR) &&
-	    (dev->type != ARPHRD_ARCNET)) {
+	    (dev->type != ARPHRD_ARCNET) &&
+	    (dev->type != ARPHRD_INFINIBAND)) {
 		/* Alas, we support only Ethernet autoconfiguration. */
 		return;
 	}

net/ipv6/ndisc.c

@@ -260,6 +260,9 @@ int ndisc_mc_map(struct in6_addr *addr, char *buf, struct net_device *dev, int d
 	case ARPHRD_ARCNET:
 		ipv6_arcnet_mc_map(addr, buf);
 		return 0;
+	case ARPHRD_INFINIBAND:
+		ipv6_ib_mc_map(addr, buf);
+		return 0;
 	default:
 		if (dir) {
 			memcpy(buf, dev->broadcast, dev->addr_len);