RDMA/mlx5: Refactor netdev affinity code

The design of representors is such that once an IB representor is created,
the netdev of representor already exists, we can use that fact to simplify
the netdev affinity code.
Signed-off-by: Mark Bloch <markb@mellanox.com>
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>

drivers/infiniband/hw/mlx5/ib_rep.c

@@ -71,6 +71,8 @@ mlx5_ib_vport_rep_load(struct mlx5_core_dev *dev, struct mlx5_eswitch_rep *rep)
 
 	ibdev->is_rep = true;
 	ibdev->port[0].rep = rep;
+	ibdev->port[0].roce.netdev =
+		mlx5_ib_get_rep_netdev(dev->priv.eswitch, rep->vport);
 	ibdev->mdev = dev;
 	ibdev->num_ports = num_ports;
 

drivers/infiniband/hw/mlx5/main.c

@@ -156,6 +156,34 @@ static int get_port_state(struct ib_device *ibdev,
 	return ret;
 }
 
+static struct mlx5_roce *mlx5_get_rep_roce(struct mlx5_ib_dev *dev,
+					   struct net_device *ndev,
+					   u8 *port_num)
+{
+	struct mlx5_eswitch *esw = dev->mdev->priv.eswitch;
+	struct net_device *rep_ndev;
+	struct mlx5_ib_port *port;
+	int i;
+
+	for (i = 0; i < dev->num_ports; i++) {
+		port  = &dev->port[i];
+		if (!port->rep)
+			continue;
+
+		read_lock(&port->roce.netdev_lock);
+		rep_ndev = mlx5_ib_get_rep_netdev(esw,
+						  port->rep->vport);
+		if (rep_ndev == ndev) {
+			read_unlock(&port->roce.netdev_lock);
+			*port_num = i + 1;
+			return &port->roce;
+		}
+		read_unlock(&port->roce.netdev_lock);
+	}
+
+	return NULL;
+}
+
 static int mlx5_netdev_event(struct notifier_block *this,
 			     unsigned long event, void *ptr)
 {
@@ -172,22 +200,17 @@ static int mlx5_netdev_event(struct notifier_block *this,
 
 	switch (event) {
 	case NETDEV_REGISTER:
+		/* Should already be registered during the load */
+		if (ibdev->is_rep)
+			break;
 		write_lock(&roce->netdev_lock);
-		if (ibdev->is_rep) {
-			struct mlx5_eswitch *esw = ibdev->mdev->priv.eswitch;
-			struct mlx5_eswitch_rep	*rep = ibdev->port[0].rep;
-			struct net_device *rep_ndev;
-
-			rep_ndev = mlx5_ib_get_rep_netdev(esw, rep->vport);
-			if (rep_ndev == ndev)
-				roce->netdev = ndev;
-		} else if (ndev->dev.parent == &mdev->pdev->dev) {
+		if (ndev->dev.parent == &mdev->pdev->dev)
 			roce->netdev = ndev;
-		}
 		write_unlock(&roce->netdev_lock);
 		break;
 
 	case NETDEV_UNREGISTER:
+		/* In case of reps, ib device goes away before the netdevs */
 		write_lock(&roce->netdev_lock);
 		if (roce->netdev == ndev)
 			roce->netdev = NULL;
@@ -205,6 +228,10 @@ static int mlx5_netdev_event(struct notifier_block *this,
 			dev_put(lag_ndev);
 		}
 
+		if (ibdev->is_rep)
+			roce = mlx5_get_rep_roce(ibdev, ndev, &port_num);
+		if (!roce)
+			return NOTIFY_DONE;
 		if ((upper == ndev || (!upper && ndev == roce->netdev))
 		    && ibdev->ib_active) {
 			struct ib_event ibev = { };