libcxgb,iw_cxgb4,cxgbit: add cxgb_find_route()

Add cxgb_find_route() in libcxgb_cm.c to remove
it's duplicate definitions from cxgb4/cm.c and
cxgbit/cxgbit_cm.c.

Signed-off-by: Varun Prakash <varun@chelsio.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 44 insertions, 0 deletions

diff --git a/drivers/net/ethernet/chelsio/libcxgb/libcxgb_cm.c b/drivers/net/ethernet/chelsio/libcxgb/libcxgb_cm.c
index d7342bb7205d..a31841247954 100644
--- a/drivers/net/ethernet/chelsio/libcxgb/libcxgb_cm.c
+++ b/drivers/net/ethernet/chelsio/libcxgb/libcxgb_cm.c
@@ -32,6 +32,7 @@
 
 #include <linux/tcp.h>
 #include <linux/ipv6.h>
+#include <net/route.h>
 
 #include "libcxgb_cm.h"
 
@@ -70,3 +71,46 @@ cxgb_get_4tuple(struct cpl_pass_accept_req *req, enum chip_type type,
 	*local_port = tcp->dest;
 }
 EXPORT_SYMBOL(cxgb_get_4tuple);
+
+static bool
+cxgb_our_interface(struct cxgb4_lld_info *lldi,
+		   struct net_device *(*get_real_dev)(struct net_device *),
+		   struct net_device *egress_dev)
+{
+	int i;
+
+	egress_dev = get_real_dev(egress_dev);
+	for (i = 0; i < lldi->nports; i++)
+		if (lldi->ports[i] == egress_dev)
+			return true;
+	return false;
+}
+
+struct dst_entry *
+cxgb_find_route(struct cxgb4_lld_info *lldi,
+		struct net_device *(*get_real_dev)(struct net_device *),
+		__be32 local_ip, __be32 peer_ip, __be16 local_port,
+		__be16 peer_port, u8 tos)
+{
+	struct rtable *rt;
+	struct flowi4 fl4;
+	struct neighbour *n;
+
+	rt = ip_route_output_ports(&init_net, &fl4, NULL, peer_ip, local_ip,
+				   peer_port, local_port, IPPROTO_TCP,
+				   tos, 0);
+	if (IS_ERR(rt))
+		return NULL;
+	n = dst_neigh_lookup(&rt->dst, &peer_ip);
+	if (!n)
+		return NULL;
+	if (!cxgb_our_interface(lldi, get_real_dev, n->dev) &&
+	    !(n->dev->flags & IFF_LOOPBACK)) {
+		neigh_release(n);
+		dst_release(&rt->dst);
+		return NULL;
+	}
+	neigh_release(n);
+	return &rt->dst;
+}
+EXPORT_SYMBOL(cxgb_find_route);