net/mlx5: Lag, add net namespace support

Update the LAG implementation to support net namespace isolation.

With recent changes to the devcom framework allowing namespace-aware
matching, the LAG layer is updated to register devcom clients with the
associated net namespace. This ensures that LAG formation only occurs
between mlx5 interfaces that reside in the same namespace.

This change ensures that devices in different namespaces do not interfere
with each other's LAG setup and behavior. For example, if two PCI PFs are
in the same namespace, they are eligible to form a hardware LAG.

In addition, reload behavior for LAG is adjusted to handle namespace
contexts appropriately.

Signed-off-by: Shay Drory <[email protected]>
Reviewed-by: Mark Bloch <[email protected]>
Reviewed-by: Parav Pandit <[email protected]>
Signed-off-by: Tariq Toukan <[email protected]>
Signed-off-by: NipaLocal <nipa@local>

Author: shayshyi

drivers/net/ethernet/mellanox/mlx5/core/devlink.c

@@ -204,11 +204,6 @@ static int mlx5_devlink_reload_down(struct devlink *devlink, bool netns_change,
 		return 0;
 	}
 
-	if (mlx5_lag_is_active(dev)) {
-		NL_SET_ERR_MSG_MOD(extack, "reload is unsupported in Lag mode");
-		return -EOPNOTSUPP;
-	}
-
 	if (mlx5_core_is_mp_slave(dev)) {
 		NL_SET_ERR_MSG_MOD(extack, "reload is unsupported for multi port slave");
 		return -EOPNOTSUPP;

drivers/net/ethernet/mellanox/mlx5/core/lag/lag.c

@@ -35,6 +35,7 @@
 #include <linux/mlx5/driver.h>
 #include <linux/mlx5/eswitch.h>
 #include <linux/mlx5/vport.h>
+#include "lib/mlx5.h"
 #include "lib/devcom.h"
 #include "mlx5_core.h"
 #include "eswitch.h"
@@ -231,9 +232,13 @@ static void mlx5_do_bond_work(struct work_struct *work);
 static void mlx5_ldev_free(struct kref *ref)
 {
 	struct mlx5_lag *ldev = container_of(ref, struct mlx5_lag, ref);
+	struct net *net;
+
+	if (ldev->nb.notifier_call) {
+		net = read_pnet(&ldev->net);
+		unregister_netdevice_notifier_net(net, &ldev->nb);
+	}
 
-	if (ldev->nb.notifier_call)
-		unregister_netdevice_notifier_net(&init_net, &ldev->nb);
 	mlx5_lag_mp_cleanup(ldev);
 	cancel_delayed_work_sync(&ldev->bond_work);
 	destroy_workqueue(ldev->wq);
@@ -271,7 +276,8 @@ static struct mlx5_lag *mlx5_lag_dev_alloc(struct mlx5_core_dev *dev)
 	INIT_DELAYED_WORK(&ldev->bond_work, mlx5_do_bond_work);
 
 	ldev->nb.notifier_call = mlx5_lag_netdev_event;
-	if (register_netdevice_notifier_net(&init_net, &ldev->nb)) {
+	write_pnet(&ldev->net, mlx5_core_net(dev));
+	if (register_netdevice_notifier_net(read_pnet(&ldev->net), &ldev->nb)) {
 		ldev->nb.notifier_call = NULL;
 		mlx5_core_err(dev, "Failed to register LAG netdev notifier\n");
 	}
@@ -1413,6 +1419,8 @@ static int mlx5_lag_register_hca_devcom_comp(struct mlx5_core_dev *dev)
 {
 	struct mlx5_devcom_match_attr attr = {
 		.key.val = mlx5_query_nic_system_image_guid(dev),
+		.flags = MLX5_DEVCOM_MATCH_FLAGS_NS,
+		.net = mlx5_core_net(dev),
 	};
 
 	/* This component is use to sync adding core_dev to lag_dev and to sync

drivers/net/ethernet/mellanox/mlx5/core/lag/lag.h

@@ -67,6 +67,7 @@ struct mlx5_lag {
 	struct workqueue_struct   *wq;
 	struct delayed_work       bond_work;
 	struct notifier_block     nb;
+	possible_net_t net;
 	struct lag_mp             lag_mp;
 	struct mlx5_lag_port_sel  port_sel;
 	/* Protect lag fields/state changes */