[PATCH net V5 1/3] bonding: implement xdo_dev_state_free and call it after deletion

[Jianbo Liu <jianbol@nvidia.com>]

Add this implementation for bonding, so hardware resources can be
freed from the active slave after xfrm state is deleted. The netdev
used to invoke xdo_dev_state_free callback, is saved in the xfrm state
(xs->xso.real_dev), which is also the bond's active slave.

And call it when deleting all SAs from old active real interface while
switching current active slave.

Fixes: 9a5605505d9c ("bonding: Add struct bond_ipesc to manage SA")
Signed-off-by: Jianbo Liu <jianbol@nvidia.com>
Signed-off-by: Tariq Toukan <tariqt@nvidia.com>
Reviewed-by: Hangbin Liu <liuhangbin@gmail.com>
---
 drivers/net/bonding/bond_main.c | 32 ++++++++++++++++++++++++++++++++
 1 file changed, 32 insertions(+)

diff --git a/drivers/net/bonding/bond_main.c b/drivers/net/bonding/bond_main.c
index f74bacf071fc..f191a48c7766 100644
--- a/drivers/net/bonding/bond_main.c
+++ b/drivers/net/bonding/bond_main.c
@@ -581,12 +581,43 @@ static void bond_ipsec_del_sa_all(struct bonding *bond)
 				   __func__);
 		} else {
 			slave->dev->xfrmdev_ops->xdo_dev_state_delete(ipsec->xs);
+			if (slave->dev->xfrmdev_ops->xdo_dev_state_free)
+				slave->dev->xfrmdev_ops->xdo_dev_state_free(ipsec->xs);
 		}
 	}
 	spin_unlock_bh(&bond->ipsec_lock);
 	rcu_read_unlock();
 }
 
+static void bond_ipsec_free_sa(struct xfrm_state *xs)
+{
+	struct net_device *bond_dev = xs->xso.dev;
+	struct net_device *real_dev;
+	struct bonding *bond;
+	struct slave *slave;
+
+	if (!bond_dev)
+		return;
+
+	rcu_read_lock();
+	bond = netdev_priv(bond_dev);
+	slave = rcu_dereference(bond->curr_active_slave);
+	real_dev = slave ? slave->dev : NULL;
+	rcu_read_unlock();
+
+	if (!slave)
+		return;
+
+	if (!xs->xso.real_dev)
+		return;
+
+	WARN_ON(xs->xso.real_dev != real_dev);
+
+	if (real_dev && real_dev->xfrmdev_ops &&
+	    real_dev->xfrmdev_ops->xdo_dev_state_free)
+		real_dev->xfrmdev_ops->xdo_dev_state_free(xs);
+}
+
 /**
  * bond_ipsec_offload_ok - can this packet use the xfrm hw offload
  * @skb: current data packet
@@ -627,6 +658,7 @@ static bool bond_ipsec_offload_ok(struct sk_buff *skb, struct xfrm_state *xs)
 static const struct xfrmdev_ops bond_xfrmdev_ops = {
 	.xdo_dev_state_add = bond_ipsec_add_sa,
 	.xdo_dev_state_delete = bond_ipsec_del_sa,
+	.xdo_dev_state_free = bond_ipsec_free_sa,
 	.xdo_dev_offload_ok = bond_ipsec_offload_ok,
 };
 #endif /* CONFIG_XFRM_OFFLOAD */
-- 
2.21.0