RDMA/nes: Fix routed RDMA connections

Fix routed RDMA connections to destinations where the next hop is not
the final destination.  Use neigh_*() to properly locate neighbor.

Signed-off-by: Bob Sharp <bsharp@neteffect.com>
Signed-off-by: Sweta Bhatt <sweta.bhatt@einfochips.com>
Signed-off-by: Chien Tung <ctung@neteffect.com>

1 files changed, 30 insertions, 8 deletions

diff --git a/drivers/infiniband/hw/nes/nes_cm.c b/drivers/infiniband/hw/nes/nes_cm.c
index 08f2b3e80fcb..d69226d7102e 100644
--- a/drivers/infiniband/hw/nes/nes_cm.c
+++ b/drivers/infiniband/hw/nes/nes_cm.c
@@ -52,7 +52,7 @@
 #include <linux/random.h>
 #include <linux/list.h>
 #include <linux/threads.h>
-
+#include <net/arp.h>
 #include <net/neighbour.h>
 #include <net/route.h>
 #include <net/ip_fib.h>
@@ -1019,23 +1019,43 @@ static inline int mini_cm_accelerated(struct nes_cm_core *cm_core,
 
 
 /**
- * nes_addr_send_arp
+ * nes_addr_resolve_neigh
  */
-static void nes_addr_send_arp(u32 dst_ip)
+static int nes_addr_resolve_neigh(struct nes_vnic *nesvnic, u32 dst_ip)
 {
         struct rtable *rt;
         struct flowi fl;
+        struct neighbour *neigh;
+        int rc = -1;
+        DECLARE_MAC_BUF(mac);
 
         memset(&fl, 0, sizeof fl);
         fl.nl_u.ip4_u.daddr = htonl(dst_ip);
         if (ip_route_output_key(&init_net, &rt, &fl)) {
                 printk("%s: ip_route_output_key failed for 0x%08X\n",
                                 __func__, dst_ip);
-                return;
+                return rc;
+        }
+
+        neigh = neigh_lookup(&arp_tbl, &rt->rt_gateway, nesvnic->netdev);
+        if (neigh) {
+                if (neigh->nud_state & NUD_VALID) {
+                        nes_debug(NES_DBG_CM, "Neighbor MAC address for 0x%08X"
+                                  " is %s, Gateway is 0x%08X \n", dst_ip,
+                                  print_mac(mac, neigh->ha), ntohl(rt->rt_gateway));
+                        nes_manage_arp_cache(nesvnic->netdev, neigh->ha,
+                                             dst_ip, NES_ARP_ADD);
+                        rc = nes_arp_table(nesvnic->nesdev, dst_ip, NULL,
+                                           NES_ARP_RESOLVE);
+                }
+                neigh_release(neigh);
         }
 
-        neigh_event_send(rt->u.dst.neighbour, NULL);
+        if ((neigh == NULL) || (!(neigh->nud_state & NUD_VALID)))
+                neigh_event_send(rt->u.dst.neighbour, NULL);
+
         ip_rt_put(rt);
+        return rc;
 }
 
 
@@ -1108,9 +1128,11 @@ static struct nes_cm_node *make_cm_node(struct nes_cm_core *cm_core,
         /* get the mac addr for the remote node */
         arpindex = nes_arp_table(nesdev, cm_node->rem_addr, NULL, NES_ARP_RESOLVE);
         if (arpindex < 0) {
-                kfree(cm_node);
-                nes_addr_send_arp(cm_info->rem_addr);
-                return NULL;
+                arpindex = nes_addr_resolve_neigh(nesvnic, cm_info->rem_addr);
+                if (arpindex < 0) {
+                        kfree(cm_node);
+                        return NULL;
+                }
         }
 
         /* copy the mac addr to node context */