xen-netback: use toeplitz hash value from the frontend

This patch adds code to xen-netback to use the value in a toeplitz hash
extra info fragment passed from the VM frontend in a transmit-side packet
to set the skb hash accordingly.

Signed-off-by: Paul Durrant <paul.durrant@citrix.com>
Cc: Ian Campbell <ian.campbell@citrix.com>
Cc: Wei Liu <wei.liu2@citrix.com>

diff --git a/drivers/net/xen-netback/netback.c b/drivers/net/xen-netback/netback.c
index 57c91fef78aee460719345ced832c2c281e9ef19..f550b8afc36f228cf0a10140454cb471086079fd 100644 (file)
--- a/drivers/net/xen-netback/netback.c
+++ b/drivers/net/xen-netback/netback.c
@@ -1341,6 +1341,28 @@ void xenvif_mcast_addr_list_free(struct xenvif *vif)
        }
 }
 
+static void xenvif_set_skb_hash(struct xenvif *vif,
+                               struct sk_buff *skb,
+                               struct xen_netif_extra_info *extra)
+{
+       u32 hash = *(u32 *)extra->u.toeplitz.value;
+       enum pkt_hash_types type = PKT_HASH_TYPE_NONE;
+
+       switch (extra->u.toeplitz.type) {
+       case _XEN_NETIF_CTRL_TOEPLITZ_HASH_IPV4:
+       case _XEN_NETIF_CTRL_TOEPLITZ_HASH_IPV6:
+               type = PKT_HASH_TYPE_L3;
+               break;
+
+       case _XEN_NETIF_CTRL_TOEPLITZ_HASH_IPV4_TCP:
+       case _XEN_NETIF_CTRL_TOEPLITZ_HASH_IPV6_TCP:
+               type = PKT_HASH_TYPE_L4;
+               break;
+       }
+
+       skb_set_hash(skb, hash, type);
+}
+
 static void xenvif_tx_build_gops(struct xenvif_queue *queue,
                                     int budget,
                                     unsigned *copy_ops,
@@ -1502,6 +1524,13 @@ static void xenvif_tx_build_gops(struct xenvif_queue *queue,
                        }
                }
 
+               if (extras[XEN_NETIF_EXTRA_TYPE_TOEPLITZ - 1].type) {
+                       struct xen_netif_extra_info *extra;
+
+                       extra = &extras[XEN_NETIF_EXTRA_TYPE_TOEPLITZ - 1];
+                       xenvif_set_skb_hash(queue->vif, skb, extra);
+               }
+
                XENVIF_TX_CB(skb)->pending_idx = pending_idx;
 
                __skb_put(skb, data_len);