net/mlx5: Move the esw mode notifier chain outside the devlink lock

The esw mode change notifier chain is initialized/cleaned up in
mlx5_init_one() / mlx5_uninit_one() with the devlink lock held.

Move the notifier head from the eswitch struct into mlx5_priv directly,
and initialize it outside the critical section. This will allow notifier
registration to happen earlier in the init procedure in subsequent
patches.

Signed-off-by: Cosmin Ratiu <[e-mail]>
Reviewed-by: Carolina Jubran <[e-mail]>
Signed-off-by: Tariq Toukan <[e-mail]>
Link: https://patch.msgid.link/[e-mail]
Signed-off-by: Jakub Kicinski <[e-mail]>

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

···
 
 	info.new_mode = mode;
 
-	blocking_notifier_call_chain(&esw->n_head, 0, &info);
+	blocking_notifier_call_chain(&esw->dev->priv.esw_n_head, 0, &info);
 }
 
 static int mlx5_esw_egress_acls_init(struct mlx5_core_dev *dev)
···
 		esw->offloads.encap = DEVLINK_ESWITCH_ENCAP_MODE_BASIC;
 	else
 		esw->offloads.encap = DEVLINK_ESWITCH_ENCAP_MODE_NONE;
-	BLOCKING_INIT_NOTIFIER_HEAD(&esw->n_head);
 
 	esw_info(dev,
 		 "Total vports %d, per vport: max uc(%d) max mc(%d)\n",
···
 		dev1->priv.eswitch->mode == MLX5_ESWITCH_OFFLOADS);
 }
 
-int mlx5_esw_event_notifier_register(struct mlx5_eswitch *esw, struct notifier_block *nb)
+int mlx5_esw_event_notifier_register(struct mlx5_core_dev *dev,
+				     struct notifier_block *nb)
 {
-	return blocking_notifier_chain_register(&esw->n_head, nb);
+	return blocking_notifier_chain_register(&dev->priv.esw_n_head, nb);
 }
 
-void mlx5_esw_event_notifier_unregister(struct mlx5_eswitch *esw, struct notifier_block *nb)
+void mlx5_esw_event_notifier_unregister(struct mlx5_core_dev *dev,
+					struct notifier_block *nb)
 {
-	blocking_notifier_chain_unregister(&esw->n_head, nb);
+	blocking_notifier_chain_unregister(&dev->priv.esw_n_head, nb);
 }
 
 /**

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

···
 	struct {
 		u32             large_group_num;
 	}  params;
-	struct blocking_notifier_head n_head;
 	struct xarray paired;
 	struct mlx5_devcom_comp_dev *devcom;
 	u16 enabled_ipsec_vf_count;
···
 	u16 new_mode;
 };
 
-int mlx5_esw_event_notifier_register(struct mlx5_eswitch *esw, struct notifier_block *n);
-void mlx5_esw_event_notifier_unregister(struct mlx5_eswitch *esw, struct notifier_block *n);
+int mlx5_esw_event_notifier_register(struct mlx5_core_dev *dev,
+				     struct notifier_block *n);
+void mlx5_esw_event_notifier_unregister(struct mlx5_core_dev *dev,
+					struct notifier_block *n);
 
 bool mlx5_esw_hold(struct mlx5_core_dev *dev);
 void mlx5_esw_release(struct mlx5_core_dev *dev);

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

···
 		return err;
 	}
 
+	BLOCKING_INIT_NOTIFIER_HEAD(&dev->priv.esw_n_head);
+
 	return 0;
 }
 

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

···
 	xa_init(&table->function_ids);
 	dev->priv.sf_table = table;
 	table->esw_nb.notifier_call = mlx5_sf_esw_event;
-	err = mlx5_esw_event_notifier_register(dev->priv.eswitch, &table->esw_nb);
+	err = mlx5_esw_event_notifier_register(dev, &table->esw_nb);
 	if (err)
 		goto reg_err;
 
···
 	return 0;
 
 vhca_err:
-	mlx5_esw_event_notifier_unregister(dev->priv.eswitch, &table->esw_nb);
+	mlx5_esw_event_notifier_unregister(dev, &table->esw_nb);
 reg_err:
 	mutex_destroy(&table->sf_state_lock);
 	kfree(table);
···
 
 	mlx5_blocking_notifier_unregister(dev, &table->mdev_nb);
 	mlx5_vhca_event_notifier_unregister(table->dev, &table->vhca_nb);
-	mlx5_esw_event_notifier_unregister(dev->priv.eswitch, &table->esw_nb);
+	mlx5_esw_event_notifier_unregister(dev, &table->esw_nb);
 	mutex_destroy(&table->sf_state_lock);
 	WARN_ON(!xa_empty(&table->function_ids));
 	kfree(table);

include/linux/mlx5/driver.h

···
 
 	struct mlx5_flow_steering *steering;
 	struct mlx5_mpfs        *mpfs;
+	struct blocking_notifier_head esw_n_head;
 	struct mlx5_eswitch     *eswitch;
 	struct mlx5_core_sriov	sriov;
 	struct mlx5_lag		*lag;