devlink: Delete reload enable/disable interface

Commit a0c76345 ("devlink: disallow reload operation during device
cleanup") added devlink_reload_{enable,disable}() APIs to prevent reload
operation from racing with device probe/dismantle.

After recent changes to move devlink_register() to the end of device
probe and devlink_unregister() to the beginning of device dismantle,
these races can no longer happen. Reload operations will be denied if
the devlink instance is unregistered and devlink_unregister() will block
until all in-flight operations are done.

Therefore, remove these devlink_reload_{enable,disable}() APIs.
Signed-off-by: Leon Romanovsky <leonro@nvidia.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

drivers/net/ethernet/hisilicon/hns3/hns3pf/hclge_devlink.c

@@ -121,7 +121,6 @@ int hclge_devlink_init(struct hclge_dev *hdev)
 
 	devlink_set_features(devlink, DEVLINK_F_RELOAD);
 	devlink_register(devlink);
-	devlink_reload_enable(devlink);
 	return 0;
 }
 
@@ -129,8 +128,6 @@ void hclge_devlink_uninit(struct hclge_dev *hdev)
 {
 	struct devlink *devlink = hdev->devlink;
 
-	devlink_reload_disable(devlink);
-
 	devlink_unregister(devlink);
 
 	devlink_free(devlink);

drivers/net/ethernet/hisilicon/hns3/hns3vf/hclgevf_devlink.c

@@ -123,7 +123,6 @@ int hclgevf_devlink_init(struct hclgevf_dev *hdev)
 
 	devlink_set_features(devlink, DEVLINK_F_RELOAD);
 	devlink_register(devlink);
-	devlink_reload_enable(devlink);
 	return 0;
 }
 
@@ -131,8 +130,6 @@ void hclgevf_devlink_uninit(struct hclgevf_dev *hdev)
 {
 	struct devlink *devlink = hdev->devlink;
 
-	devlink_reload_disable(devlink);
-
 	devlink_unregister(devlink);
 
 	devlink_free(devlink);

drivers/net/ethernet/mellanox/mlx4/main.c

@@ -4027,7 +4027,6 @@ static int mlx4_init_one(struct pci_dev *pdev, const struct pci_device_id *id)
 	pci_save_state(pdev);
 	devlink_set_features(devlink, DEVLINK_F_RELOAD);
 	devlink_register(devlink);
-	devlink_reload_enable(devlink);
 	return 0;
 
 err_params_unregister:
@@ -4136,7 +4135,6 @@ static void mlx4_remove_one(struct pci_dev *pdev)
 	struct devlink *devlink = priv_to_devlink(priv);
 	int active_vfs = 0;
 
-	devlink_reload_disable(devlink);
 	devlink_unregister(devlink);
 
 	if (mlx4_is_slave(dev))

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

@@ -1538,8 +1538,6 @@ static int probe_one(struct pci_dev *pdev, const struct pci_device_id *id)
 
 	pci_save_state(pdev);
 	devlink_register(devlink);
-	if (!mlx5_core_is_mp_slave(dev))
-		devlink_reload_enable(devlink);
 	return 0;
 
 err_init_one:
@@ -1559,7 +1557,6 @@ static void remove_one(struct pci_dev *pdev)
 	struct mlx5_core_dev *dev  = pci_get_drvdata(pdev);
 	struct devlink *devlink = priv_to_devlink(dev);
 
-	devlink_reload_disable(devlink);
 	devlink_unregister(devlink);
 	mlx5_crdump_disable(dev);
 	mlx5_drain_health_wq(dev);

drivers/net/ethernet/mellanox/mlx5/core/sf/dev/driver.c

@@ -47,7 +47,6 @@ static int mlx5_sf_dev_probe(struct auxiliary_device *adev, const struct auxilia
 		goto init_one_err;
 	}
 	devlink_register(devlink);
-	devlink_reload_enable(devlink);
 	return 0;
 
 init_one_err:
@@ -62,10 +61,8 @@ static int mlx5_sf_dev_probe(struct auxiliary_device *adev, const struct auxilia
 static void mlx5_sf_dev_remove(struct auxiliary_device *adev)
 {
 	struct mlx5_sf_dev *sf_dev = container_of(adev, struct mlx5_sf_dev, adev);
-	struct devlink *devlink;
+	struct devlink *devlink = priv_to_devlink(sf_dev->mdev);
 
-	devlink = priv_to_devlink(sf_dev->mdev);
-	devlink_reload_disable(devlink);
 	devlink_unregister(devlink);
 	mlx5_uninit_one(sf_dev->mdev);
 	iounmap(sf_dev->mdev->iseg);

drivers/net/ethernet/mellanox/mlxsw/core.c

@@ -2010,9 +2010,7 @@ __mlxsw_core_bus_device_register(const struct mlxsw_bus_info *mlxsw_bus_info,
 	if (!reload) {
 		devlink_set_features(devlink, DEVLINK_F_RELOAD);
 		devlink_register(devlink);
-		devlink_reload_enable(devlink);
 	}
-
 	return 0;
 
 err_driver_init:
@@ -2076,10 +2074,9 @@ void mlxsw_core_bus_device_unregister(struct mlxsw_core *mlxsw_core,
 {
 	struct devlink *devlink = priv_to_devlink(mlxsw_core);
 
-	if (!reload) {
-		devlink_reload_disable(devlink);
+	if (!reload)
 		devlink_unregister(devlink);
-	}
+
 	if (devlink_is_reload_failed(devlink)) {
 		if (!reload)
 			/* Only the parts that were not de-initialized in the

drivers/net/netdevsim/dev.c

@@ -1513,7 +1513,6 @@ int nsim_dev_probe(struct nsim_bus_dev *nsim_bus_dev)
 	nsim_dev->esw_mode = DEVLINK_ESWITCH_MODE_LEGACY;
 	devlink_set_features(devlink, DEVLINK_F_RELOAD);
 	devlink_register(devlink);
-	devlink_reload_enable(devlink);
 	return 0;
 
 err_psample_exit:
@@ -1567,9 +1566,7 @@ void nsim_dev_remove(struct nsim_bus_dev *nsim_bus_dev)
 	struct nsim_dev *nsim_dev = dev_get_drvdata(&nsim_bus_dev->dev);
 	struct devlink *devlink = priv_to_devlink(nsim_dev);
 
-	devlink_reload_disable(devlink);
 	devlink_unregister(devlink);
-
 	nsim_dev_reload_destroy(nsim_dev);
 
 	nsim_bpf_dev_exit(nsim_dev);

include/net/devlink.h

@@ -1511,8 +1511,6 @@ static inline struct devlink *devlink_alloc(const struct devlink_ops *ops,
 void devlink_set_features(struct devlink *devlink, u64 features);
 void devlink_register(struct devlink *devlink);
 void devlink_unregister(struct devlink *devlink);
-void devlink_reload_enable(struct devlink *devlink);
-void devlink_reload_disable(struct devlink *devlink);
 void devlink_free(struct devlink *devlink);
 int devlink_port_register(struct devlink *devlink,
 			  struct devlink_port *devlink_port,

net/core/devlink.c

@@ -63,8 +63,7 @@ struct devlink {
 	 * port, sb, dpipe, resource, params, region, traps and more.
 	 */
 	struct mutex lock;
-	u8 reload_failed:1,
-	   reload_enabled:1;
+	u8 reload_failed:1;
 	refcount_t refcount;
 	struct completion comp;
 	char priv[0] __aligned(NETDEV_ALIGN);
@@ -4033,9 +4032,6 @@ static int devlink_reload(struct devlink *devlink, struct net *dest_net,
 	struct net *curr_net;
 	int err;
 
-	if (!devlink->reload_enabled || !(devlink->features & DEVLINK_F_RELOAD))
-		return -EOPNOTSUPP;
-
 	memcpy(remote_reload_stats, devlink->stats.remote_reload_stats,
 	       sizeof(remote_reload_stats));
 
@@ -4103,7 +4099,7 @@ static int devlink_nl_cmd_reload(struct sk_buff *skb, struct genl_info *info)
 	u32 actions_performed;
 	int err;
 
-	if (!devlink_reload_supported(devlink->ops))
+	if (!(devlink->features & DEVLINK_F_RELOAD))
 		return -EOPNOTSUPP;
 
 	err = devlink_resources_validate(devlink, NULL, info);
@@ -9175,49 +9171,12 @@ void devlink_unregister(struct devlink *devlink)
 	wait_for_completion(&devlink->comp);
 
 	mutex_lock(&devlink_mutex);
-	WARN_ON(devlink->features & DEVLINK_F_RELOAD &&
-		devlink->reload_enabled);
 	devlink_notify_unregister(devlink);
 	xa_clear_mark(&devlinks, devlink->index, DEVLINK_REGISTERED);
 	mutex_unlock(&devlink_mutex);
 }
 EXPORT_SYMBOL_GPL(devlink_unregister);
 
-/**
- *	devlink_reload_enable - Enable reload of devlink instance
- *
- *	@devlink: devlink
- *
- *	Should be called at end of device initialization
- *	process when reload operation is supported.
- */
-void devlink_reload_enable(struct devlink *devlink)
-{
-	mutex_lock(&devlink_mutex);
-	devlink->reload_enabled = true;
-	mutex_unlock(&devlink_mutex);
-}
-EXPORT_SYMBOL_GPL(devlink_reload_enable);
-
-/**
- *	devlink_reload_disable - Disable reload of devlink instance
- *
- *	@devlink: devlink
- *
- *	Should be called at the beginning of device cleanup
- *	process when reload operation is supported.
- */
-void devlink_reload_disable(struct devlink *devlink)
-{
-	mutex_lock(&devlink_mutex);
-	/* Mutex is taken which ensures that no reload operation is in
-	 * progress while setting up forbidded flag.
-	 */
-	devlink->reload_enabled = false;
-	mutex_unlock(&devlink_mutex);
-}
-EXPORT_SYMBOL_GPL(devlink_reload_disable);
-
 /**
  *	devlink_free - Free devlink instance resources
  *
@@ -11554,7 +11513,7 @@ static void __net_exit devlink_pernet_pre_exit(struct net *net)
 		if (!net_eq(devlink_net(devlink), net))
 			goto retry;
 
-		WARN_ON(!devlink_reload_supported(devlink->ops));
+		WARN_ON(!(devlink->features & DEVLINK_F_RELOAD));
 		err = devlink_reload(devlink, &init_net,
 				     DEVLINK_RELOAD_ACTION_DRIVER_REINIT,
 				     DEVLINK_RELOAD_LIMIT_UNSPEC,