net: Add layer 2 hardware acceleration operations for macvlan devices

Add a operations structure that allows a network interface to export
the fact that it supports package forwarding in hardware between
physical interfaces and other mac layer devices assigned to it (such
as macvlans). This operaions structure can be used by virtual mac
devices to bypass software switching so that forwarding can be done
in hardware more efficiently.

Signed-off-by: John Fastabend <john.r.fastabend@intel.com>
Signed-off-by: Neil Horman <nhorman@tuxdriver.com>
CC: Andy Gospodarek <andy@greyhouse.net>
CC: "David S. Miller" <davem@davemloft.net>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 35 insertions, 1 deletions

diff --git a/drivers/net/macvlan.c b/drivers/net/macvlan.c
index cc9845ec91c1..af4aaa5893ff 100644
--- a/drivers/net/macvlan.c
+++ b/drivers/net/macvlan.c
@@ -297,7 +297,13 @@ netdev_tx_t macvlan_start_xmit(struct sk_buff *skb,
         int ret;
         const struct macvlan_dev *vlan = netdev_priv(dev);
 
-        ret = macvlan_queue_xmit(skb, dev);
+        if (vlan->fwd_priv) {
+                skb->dev = vlan->lowerdev;
+                ret = dev_hard_start_xmit(skb, skb->dev, NULL, vlan->fwd_priv);
+        } else {
+                ret = macvlan_queue_xmit(skb, dev);
+        }
+
         if (likely(ret == NET_XMIT_SUCCESS || ret == NET_XMIT_CN)) {
                 struct macvlan_pcpu_stats *pcpu_stats;
 
@@ -347,6 +353,21 @@ static int macvlan_open(struct net_device *dev)
                 goto hash_add;
         }
 
+        if (lowerdev->features & NETIF_F_HW_L2FW_DOFFLOAD) {
+                vlan->fwd_priv =
+                      lowerdev->netdev_ops->ndo_dfwd_add_station(lowerdev, dev);
+
+                /* If we get a NULL pointer back, or if we get an error
+                 * then we should just fall through to the non accelerated path
+                 */
+                if (IS_ERR_OR_NULL(vlan->fwd_priv)) {
+                        vlan->fwd_priv = NULL;
+                } else {
+                        dev->features &= ~NETIF_F_LLTX;
+                        return 0;
+                }
+        }
+
         err = -EBUSY;
         if (macvlan_addr_busy(vlan->port, dev->dev_addr))
                 goto out;
@@ -367,6 +388,11 @@ hash_add:
 del_unicast:
         dev_uc_del(lowerdev, dev->dev_addr);
 out:
+        if (vlan->fwd_priv) {
+                lowerdev->netdev_ops->ndo_dfwd_del_station(lowerdev,
+                                                           vlan->fwd_priv);
+                vlan->fwd_priv = NULL;
+        }
         return err;
 }
 
@@ -375,6 +401,13 @@ static int macvlan_stop(struct net_device *dev)
         struct macvlan_dev *vlan = netdev_priv(dev);
         struct net_device *lowerdev = vlan->lowerdev;
 
+        if (vlan->fwd_priv) {
+                lowerdev->netdev_ops->ndo_dfwd_del_station(lowerdev,
+                                                           vlan->fwd_priv);
+                vlan->fwd_priv = NULL;
+                return 0;
+        }
+
         dev_uc_unsync(lowerdev, dev);
         dev_mc_unsync(lowerdev, dev);
 
@@ -833,6 +866,7 @@ int macvlan_common_newlink(struct net *src_net, struct net_device *dev,
         if (err < 0)
                 goto destroy_port;
 
+        dev->priv_flags |= IFF_MACVLAN;
         err = netdev_upper_dev_link(lowerdev, dev);
         if (err)
                 goto destroy_port;