IB/core: Add rdma_network_type to wc

Providers should tell IB core the wc's network type.
This is used in order to search for the proper GID in the
GID table. When using HCAs that can't provide this info,
IB core tries to deep examine the packet and extract
the GID type by itself.

We choose sgid_index and type from all the matching entries in
RDMA-CM based on hint from the IP stack and we set hop_limit for
the IP packet based on above hint from IP stack.

Signed-off-by: Matan Barak <matanb@mellanox.com>
Signed-off-by: Somnath Kotur <Somnath.Kotur@Avagotech.Com>
Signed-off-by: Doug Ledford <dledford@redhat.com>
diff --git a/drivers/infiniband/core/addr.c b/drivers/infiniband/core/addr.c
index 34b1ada..6e35299 100644
--- a/drivers/infiniband/core/addr.c
+++ b/drivers/infiniband/core/addr.c
@@ -256,6 +256,12 @@
 		goto put;
 	}
 
+	/* If there's a gateway, we're definitely in RoCE v2 (as RoCE v1 isn't
+	 * routable) and we could set the network type accordingly.
+	 */
+	if (rt->rt_uses_gateway)
+		addr->network = RDMA_NETWORK_IPV4;
+
 	ret = dst_fetch_ha(&rt->dst, addr, &fl4.daddr);
 put:
 	ip_rt_put(rt);
@@ -270,6 +276,7 @@
 {
 	struct flowi6 fl6;
 	struct dst_entry *dst;
+	struct rt6_info *rt;
 	int ret;
 
 	memset(&fl6, 0, sizeof fl6);
@@ -281,6 +288,7 @@
 	if ((ret = dst->error))
 		goto put;
 
+	rt = (struct rt6_info *)dst;
 	if (ipv6_addr_any(&fl6.saddr)) {
 		ret = ipv6_dev_get_saddr(addr->net, ip6_dst_idev(dst)->dev,
 					 &fl6.daddr, 0, &fl6.saddr);
@@ -304,6 +312,12 @@
 		goto put;
 	}
 
+	/* If there's a gateway, we're definitely in RoCE v2 (as RoCE v1 isn't
+	 * routable) and we could set the network type accordingly.
+	 */
+	if (rt->rt6i_flags & RTF_GATEWAY)
+		addr->network = RDMA_NETWORK_IPV6;
+
 	ret = dst_fetch_ha(dst, addr, &fl6.daddr);
 put:
 	dst_release(dst);