mlx4: Implement IP based gids support for RoCE/SRIOV

Since there is no connection between the MAC/VLAN and the GID
when using IP-based addressing, the proxy QP1 (running on the
slave) must pass the source-mac, destination-mac, and vlan_id
information separately from the GID. Additionally, the Host
must pass the remote source-mac and vlan_id back to the slave,

This is achieved as follows:
Outgoing MADs:
    1. Source MAC: obtained from the CQ completion structure
       (struct ib_wc, smac field).
    2. Destination MAC: obtained from the tunnel header
    3. vlan_id: obtained from the tunnel header.
Incoming MADs
    1. The source (i.e., remote) MAC and vlan_id are passed in
       the tunnel header to the proxy QP1.

VST mode support:
     For outgoing MADs,  the vlan_id obtained from the header is
        discarded, and the vlan_id specified by the Hypervisor is used
        instead.
     For incoming MADs, the incoming vlan_id (in the wc) is discarded, and the
        "invalid" vlan (0xffff)  is substituted when forwarding to the slave.

Signed-off-by: Moni Shoua <monis@mellanox.co.il>
Signed-off-by: Jack Morgenstein <jackm@dev.mellanox.co.il>
Signed-off-by: Or Gerlitz <ogerlitz@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/drivers/net/ethernet/mellanox/mlx4/cmd.c b/drivers/net/ethernet/mellanox/mlx4/cmd.c
index 0d02fba..2b0b45e 100644
--- a/drivers/net/ethernet/mellanox/mlx4/cmd.c
+++ b/drivers/net/ethernet/mellanox/mlx4/cmd.c
@@ -2289,6 +2289,30 @@
 }
 EXPORT_SYMBOL_GPL(mlx4_set_vf_vlan);
 
+ /* mlx4_get_slave_default_vlan -
+ * return true if VST ( default vlan)
+ * if VST, will return vlan & qos (if not NULL)
+ */
+bool mlx4_get_slave_default_vlan(struct mlx4_dev *dev, int port, int slave,
+				 u16 *vlan, u8 *qos)
+{
+	struct mlx4_vport_oper_state *vp_oper;
+	struct mlx4_priv *priv;
+
+	priv = mlx4_priv(dev);
+	vp_oper = &priv->mfunc.master.vf_oper[slave].vport[port];
+
+	if (MLX4_VGT != vp_oper->state.default_vlan) {
+		if (vlan)
+			*vlan = vp_oper->state.default_vlan;
+		if (qos)
+			*qos = vp_oper->state.default_qos;
+		return true;
+	}
+	return false;
+}
+EXPORT_SYMBOL_GPL(mlx4_get_slave_default_vlan);
+
 int mlx4_set_vf_spoofchk(struct mlx4_dev *dev, int port, int vf, bool setting)
 {
 	struct mlx4_priv *priv = mlx4_priv(dev);