[RFC net-next 1/6] drivers: net: bonding: add tc offload infastructure to bond

[John Hurley <john.hurley@netronome.com>]

Register an ndo and callback for linux bonds to offload TC block ingress
rules. Enable tc-hw-offload to be set by the user (defaults to off). When
on, the flag cannot be turned off if rules are offloaded.

Signed-off-by: John Hurley <john.hurley@netronome.com>
---
 drivers/net/bonding/bond_main.c | 64 +++++++++++++++++++++++++++++++++++++++++
 include/net/bonding.h           |  2 ++
 2 files changed, 66 insertions(+)

diff --git a/drivers/net/bonding/bond_main.c b/drivers/net/bonding/bond_main.c
index 4c19d23..e6415f6 100644
--- a/drivers/net/bonding/bond_main.c
+++ b/drivers/net/bonding/bond_main.c
@@ -325,6 +325,55 @@ static int bond_vlan_rx_kill_vid(struct net_device *bond_dev,
 	return 0;
 }
 
+/*------------------------------ TC HW Offload ------------------------------*/
+
+static inline unsigned int bond_get_offload_cnt(struct bonding *bond)
+{
+	if (!bond->tc_block)
+		return 0;
+
+	return bond->tc_block->offloadcnt;
+}
+
+static int bond_tc_relay_cb(enum tc_setup_type type, void *type_data,
+			    void *cb_priv)
+{
+	return 0;
+}
+
+static int bond_setup_tc_block(struct net_device *netdev,
+			       struct tc_block_offload *f)
+{
+	struct bonding *bond = netdev_priv(netdev);
+
+	if (f->binder_type != TCF_BLOCK_BINDER_TYPE_CLSACT_INGRESS)
+		return -EOPNOTSUPP;
+
+	switch (f->command) {
+	case TC_BLOCK_BIND:
+		bond->tc_block = f->block;
+		return tcf_block_cb_register(f->block, bond_tc_relay_cb,
+					     netdev, netdev);
+	case TC_BLOCK_UNBIND:
+		bond->tc_block = NULL;
+		tcf_block_cb_unregister(f->block, bond_tc_relay_cb, netdev);
+		return 0;
+	default:
+		return -EOPNOTSUPP;
+	}
+}
+
+static int bond_setup_tc(struct net_device *netdev, enum tc_setup_type type,
+			 void *type_data)
+{
+	switch (type) {
+	case TC_SETUP_BLOCK:
+		return bond_setup_tc_block(netdev, type_data);
+	default:
+		return -EOPNOTSUPP;
+	}
+}
+
 /*------------------------------- Link status -------------------------------*/
 
 /* Set the carrier state for the master according to the state of its
@@ -1065,6 +1114,17 @@ static netdev_features_t bond_fix_features(struct net_device *dev,
 	return features;
 }
 
+int bond_set_features(struct net_device *netdev, netdev_features_t features)
+{
+	if ((features & NETIF_F_HW_TC) <
+	    !!bond_get_offload_cnt(netdev_priv(netdev))) {
+		netdev_err(netdev, "Cannot disable TC offload while active\n");
+		return -EBUSY;
+	}
+
+	return 0;
+}
+
 #define BOND_VLAN_FEATURES	(NETIF_F_HW_CSUM | NETIF_F_SG | \
 				 NETIF_F_FRAGLIST | NETIF_F_ALL_TSO | \
 				 NETIF_F_HIGHDMA | NETIF_F_LRO)
@@ -4198,7 +4258,9 @@ static const struct net_device_ops bond_netdev_ops = {
 	.ndo_add_slave		= bond_enslave,
 	.ndo_del_slave		= bond_release,
 	.ndo_fix_features	= bond_fix_features,
+	.ndo_set_features	= bond_set_features,
 	.ndo_features_check	= passthru_features_check,
+	.ndo_setup_tc		= bond_setup_tc,
 };
 
 static const struct device_type bond_type = {
@@ -4259,6 +4321,8 @@ void bond_setup(struct net_device *bond_dev)
 
 	bond_dev->hw_features |= NETIF_F_GSO_ENCAP_ALL;
 	bond_dev->features |= bond_dev->hw_features;
+	/* Disable hw tc offload by default. */
+	bond_dev->hw_features |= NETIF_F_HW_TC;
 }
 
 /* Destroy a bonding device.
diff --git a/include/net/bonding.h b/include/net/bonding.h
index f801fc9..424b9ea 100644
--- a/include/net/bonding.h
+++ b/include/net/bonding.h
@@ -29,6 +29,7 @@
 #include <net/bond_3ad.h>
 #include <net/bond_alb.h>
 #include <net/bond_options.h>
+#include <net/pkt_cls.h>
 
 #define BOND_MAX_ARP_TARGETS	16
 
@@ -199,6 +200,7 @@ struct bonding {
 	struct   bond_up_slave __rcu *slave_arr; /* Array of usable slaves */
 	bool     force_primary;
 	s32      slave_cnt; /* never change this value outside the attach/detach wrappers */
+	struct   tcf_block *tc_block;
 	int     (*recv_probe)(const struct sk_buff *, struct bonding *,
 			      struct slave *);
 	/* mode_lock is used for mode-specific locking needs, currently used by:
-- 
2.7.4