16 files changed, 509 insertions, 60 deletions

diff --git a/drivers/net/ethernet/mellanox/mlx5/core/devlink.c b/drivers/net/ethernet/mellanox/mlx5/core/devlink.c
index af8460bb257b..3e064234f6fe 100644
--- a/drivers/net/ethernet/mellanox/mlx5/core/devlink.c
+++ b/drivers/net/ethernet/mellanox/mlx5/core/devlink.c
@@ -138,7 +138,6 @@ static int mlx5_devlink_reload_down(struct devlink *devlink, bool netns_change,
 {
 	struct mlx5_core_dev *dev = devlink_priv(devlink);
 	struct pci_dev *pdev = dev->pdev;
-	bool sf_dev_allocated;
 	int ret = 0;
 
 	if (mlx5_dev_is_lightweight(dev)) {
@@ -148,16 +147,6 @@ static int mlx5_devlink_reload_down(struct devlink *devlink, bool netns_change,
 		return 0;
 	}
 
-	sf_dev_allocated = mlx5_sf_dev_allocated(dev);
-	if (sf_dev_allocated) {
-		/* Reload results in deleting SF device which further results in
-		 * unregistering devlink instance while holding devlink_mutext.
-		 * Hence, do not support reload.
-		 */
-		NL_SET_ERR_MSG_MOD(extack, "reload is unsupported when SFs are allocated");
-		return -EOPNOTSUPP;
-	}
-
 	if (mlx5_lag_is_active(dev)) {
 		NL_SET_ERR_MSG_MOD(extack, "reload is unsupported in Lag mode");
 		return -EOPNOTSUPP;
diff --git a/drivers/net/ethernet/mellanox/mlx5/core/en/devlink.c b/drivers/net/ethernet/mellanox/mlx5/core/en/devlink.c
index c6b6e290fd79..0b1ac6e5c890 100644
--- a/drivers/net/ethernet/mellanox/mlx5/core/en/devlink.c
+++ b/drivers/net/ethernet/mellanox/mlx5/core/en/devlink.c
@@ -12,11 +12,19 @@ struct mlx5e_dev *mlx5e_create_devlink(struct device *dev,
 {
 	struct mlx5e_dev *mlx5e_dev;
 	struct devlink *devlink;
+	int err;
 
 	devlink = devlink_alloc_ns(&mlx5e_devlink_ops, sizeof(*mlx5e_dev),
 				   devlink_net(priv_to_devlink(mdev)), dev);
 	if (!devlink)
 		return ERR_PTR(-ENOMEM);
+
+	err = devl_nested_devlink_set(priv_to_devlink(mdev), devlink);
+	if (err) {
+		devlink_free(devlink);
+		return ERR_PTR(err);
+	}
+
 	devlink_register(devlink);
 	return devlink_priv(devlink);
 }
diff --git a/drivers/net/ethernet/mellanox/mlx5/core/main.c b/drivers/net/ethernet/mellanox/mlx5/core/main.c
index 15561965d2af..d17c9c31b165 100644
--- a/drivers/net/ethernet/mellanox/mlx5/core/main.c
+++ b/drivers/net/ethernet/mellanox/mlx5/core/main.c
@@ -1405,9 +1405,9 @@ err_irq_table:
 
 static void mlx5_unload(struct mlx5_core_dev *dev)
 {
+	mlx5_eswitch_disable(dev->priv.eswitch);
 	mlx5_devlink_traps_unregister(priv_to_devlink(dev));
 	mlx5_sf_dev_table_destroy(dev);
-	mlx5_eswitch_disable(dev->priv.eswitch);
 	mlx5_sriov_detach(dev);
 	mlx5_lag_remove_mdev(dev);
 	mlx5_ec_cleanup(dev);
diff --git a/drivers/net/ethernet/mellanox/mlx5/core/sf/dev/dev.h b/drivers/net/ethernet/mellanox/mlx5/core/sf/dev/dev.h
index 2a66a427ef15..b99131e95e37 100644
--- a/drivers/net/ethernet/mellanox/mlx5/core/sf/dev/dev.h
+++ b/drivers/net/ethernet/mellanox/mlx5/core/sf/dev/dev.h
@@ -19,6 +19,12 @@ struct mlx5_sf_dev {
 	u16 fn_id;
 };
 
+struct mlx5_sf_peer_devlink_event_ctx {
+	u16 fn_id;
+	struct devlink *devlink;
+	int err;
+};
+
 void mlx5_sf_dev_table_create(struct mlx5_core_dev *dev);
 void mlx5_sf_dev_table_destroy(struct mlx5_core_dev *dev);
 
diff --git a/drivers/net/ethernet/mellanox/mlx5/core/sf/dev/driver.c b/drivers/net/ethernet/mellanox/mlx5/core/sf/dev/driver.c
index 8fe82f1191bb..169c2c68ed5c 100644
--- a/drivers/net/ethernet/mellanox/mlx5/core/sf/dev/driver.c
+++ b/drivers/net/ethernet/mellanox/mlx5/core/sf/dev/driver.c
@@ -8,6 +8,20 @@
 #include "dev.h"
 #include "devlink.h"
 
+static int mlx5_core_peer_devlink_set(struct mlx5_sf_dev *sf_dev, struct devlink *devlink)
+{
+	struct mlx5_sf_peer_devlink_event_ctx event_ctx = {
+		.fn_id = sf_dev->fn_id,
+		.devlink = devlink,
+	};
+	int ret;
+
+	ret = mlx5_blocking_notifier_call_chain(sf_dev->parent_mdev,
+						MLX5_DRIVER_EVENT_SF_PEER_DEVLINK,
+						&event_ctx);
+	return ret == NOTIFY_OK ? event_ctx.err : 0;
+}
+
 static int mlx5_sf_dev_probe(struct auxiliary_device *adev, const struct auxiliary_device_id *id)
 {
 	struct mlx5_sf_dev *sf_dev = container_of(adev, struct mlx5_sf_dev, adev);
@@ -54,9 +68,21 @@ static int mlx5_sf_dev_probe(struct auxiliary_device *adev, const struct auxilia
 		mlx5_core_warn(mdev, "mlx5_init_one err=%d\n", err);
 		goto init_one_err;
 	}
+
+	err = mlx5_core_peer_devlink_set(sf_dev, devlink);
+	if (err) {
+		mlx5_core_warn(mdev, "mlx5_core_peer_devlink_set err=%d\n", err);
+		goto peer_devlink_set_err;
+	}
+
 	devlink_register(devlink);
 	return 0;
 
+peer_devlink_set_err:
+	if (mlx5_dev_is_lightweight(sf_dev->mdev))
+		mlx5_uninit_one_light(sf_dev->mdev);
+	else
+		mlx5_uninit_one(sf_dev->mdev);
 init_one_err:
 	iounmap(mdev->iseg);
 remap_err:
diff --git a/drivers/net/ethernet/mellanox/mlx5/core/sf/devlink.c b/drivers/net/ethernet/mellanox/mlx5/core/sf/devlink.c
index e34a8f88c518..964a5b1876f3 100644
--- a/drivers/net/ethernet/mellanox/mlx5/core/sf/devlink.c
+++ b/drivers/net/ethernet/mellanox/mlx5/core/sf/devlink.c
@@ -28,6 +28,7 @@ struct mlx5_sf_table {
 	struct mutex sf_state_lock; /* Serializes sf state among user cmds & vhca event handler. */
 	struct notifier_block esw_nb;
 	struct notifier_block vhca_nb;
+	struct notifier_block mdev_nb;
 };
 
 static struct mlx5_sf *
@@ -511,6 +512,35 @@ static int mlx5_sf_esw_event(struct notifier_block *nb, unsigned long event, voi
 	return 0;
 }
 
+static int mlx5_sf_mdev_event(struct notifier_block *nb, unsigned long event, void *data)
+{
+	struct mlx5_sf_table *table = container_of(nb, struct mlx5_sf_table, mdev_nb);
+	struct mlx5_sf_peer_devlink_event_ctx *event_ctx = data;
+	int ret = NOTIFY_DONE;
+	struct mlx5_sf *sf;
+
+	if (event != MLX5_DRIVER_EVENT_SF_PEER_DEVLINK)
+		return NOTIFY_DONE;
+
+	table = mlx5_sf_table_try_get(table->dev);
+	if (!table)
+		return NOTIFY_DONE;
+
+	mutex_lock(&table->sf_state_lock);
+	sf = mlx5_sf_lookup_by_function_id(table, event_ctx->fn_id);
+	if (!sf)
+		goto out;
+
+	event_ctx->err = devl_port_fn_devlink_set(&sf->dl_port.dl_port,
+						  event_ctx->devlink);
+
+	ret = NOTIFY_OK;
+out:
+	mutex_unlock(&table->sf_state_lock);
+	mlx5_sf_table_put(table);
+	return ret;
+}
+
 static bool mlx5_sf_table_supported(const struct mlx5_core_dev *dev)
 {
 	return dev->priv.eswitch && MLX5_ESWITCH_MANAGER(dev) &&
@@ -544,6 +574,9 @@ int mlx5_sf_table_init(struct mlx5_core_dev *dev)
 	if (err)
 		goto vhca_err;
 
+	table->mdev_nb.notifier_call = mlx5_sf_mdev_event;
+	mlx5_blocking_notifier_register(dev, &table->mdev_nb);
+
 	return 0;
 
 vhca_err:
@@ -562,6 +595,7 @@ void mlx5_sf_table_cleanup(struct mlx5_core_dev *dev)
 	if (!table)
 		return;
 
+	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);
 	WARN_ON(refcount_read(&table->refcount));
diff --git a/drivers/net/ethernet/mellanox/mlxsw/core_linecard_dev.c b/drivers/net/ethernet/mellanox/mlxsw/core_linecard_dev.c
index af37e650a8ad..e8d6fe35bf36 100644
--- a/drivers/net/ethernet/mellanox/mlxsw/core_linecard_dev.c
+++ b/drivers/net/ethernet/mellanox/mlxsw/core_linecard_dev.c
@@ -132,6 +132,7 @@ static int mlxsw_linecard_bdev_probe(struct auxiliary_device *adev,
 	struct mlxsw_linecard *linecard = linecard_bdev->linecard;
 	struct mlxsw_linecard_dev *linecard_dev;
 	struct devlink *devlink;
+	int err;
 
 	devlink = devlink_alloc(&mlxsw_linecard_dev_devlink_ops,
 				sizeof(*linecard_dev), &adev->dev);
@@ -141,8 +142,12 @@ static int mlxsw_linecard_bdev_probe(struct auxiliary_device *adev,
 	linecard_dev->linecard = linecard_bdev->linecard;
 	linecard_bdev->linecard_dev = linecard_dev;
 
+	err = devlink_linecard_nested_dl_set(linecard->devlink_linecard, devlink);
+	if (err) {
+		devlink_free(devlink);
+		return err;
+	}
 	devlink_register(devlink);
-	devlink_linecard_nested_dl_set(linecard->devlink_linecard, devlink);
 	return 0;
 }
 
@@ -151,9 +156,7 @@ static void mlxsw_linecard_bdev_remove(struct auxiliary_device *adev)
 	struct mlxsw_linecard_bdev *linecard_bdev =
 			container_of(adev, struct mlxsw_linecard_bdev, adev);
 	struct devlink *devlink = priv_to_devlink(linecard_bdev->linecard_dev);
-	struct mlxsw_linecard *linecard = linecard_bdev->linecard;
 
-	devlink_linecard_nested_dl_set(linecard->devlink_linecard, NULL);
 	devlink_unregister(devlink);
 	devlink_free(devlink);
 }
diff --git a/include/linux/mlx5/device.h b/include/linux/mlx5/device.h
index 4d5be378fa8c..8fbe22de16ef 100644
--- a/include/linux/mlx5/device.h
+++ b/include/linux/mlx5/device.h
@@ -366,6 +366,7 @@ enum mlx5_driver_event {
 	MLX5_DRIVER_EVENT_UPLINK_NETDEV,
 	MLX5_DRIVER_EVENT_MACSEC_SA_ADDED,
 	MLX5_DRIVER_EVENT_MACSEC_SA_DELETED,
+	MLX5_DRIVER_EVENT_SF_PEER_DEVLINK,
 };
 
 enum {
diff --git a/include/net/devlink.h b/include/net/devlink.h
index 29fd1b4ee654..fad8e36e3d98 100644
--- a/include/net/devlink.h
+++ b/include/net/devlink.h
@@ -150,6 +150,7 @@ struct devlink_port {
 
 	struct devlink_rate *devlink_rate;
 	struct devlink_linecard *linecard;
+	u32 rel_index;
 };
 
 struct devlink_port_new_attrs {
@@ -1697,6 +1698,8 @@ void devlink_port_attrs_pci_vf_set(struct devlink_port *devlink_port, u32 contro
 void devlink_port_attrs_pci_sf_set(struct devlink_port *devlink_port,
 				   u32 controller, u16 pf, u32 sf,
 				   bool external);
+int devl_port_fn_devlink_set(struct devlink_port *devlink_port,
+			     struct devlink *fn_devlink);
 struct devlink_rate *
 devl_rate_node_create(struct devlink *devlink, void *priv, char *node_name,
 		      struct devlink_rate *parent);
@@ -1717,8 +1720,8 @@ void devlink_linecard_provision_clear(struct devlink_linecard *linecard);
 void devlink_linecard_provision_fail(struct devlink_linecard *linecard);
 void devlink_linecard_activate(struct devlink_linecard *linecard);
 void devlink_linecard_deactivate(struct devlink_linecard *linecard);
-void devlink_linecard_nested_dl_set(struct devlink_linecard *linecard,
-				    struct devlink *nested_devlink);
+int devlink_linecard_nested_dl_set(struct devlink_linecard *linecard,
+				   struct devlink *nested_devlink);
 int devl_sb_register(struct devlink *devlink, unsigned int sb_index,
 		     u32 size, u16 ingress_pools_count,
 		     u16 egress_pools_count, u16 ingress_tc_count,
@@ -1918,6 +1921,8 @@ devlink_health_reporter_state_update(struct devlink_health_reporter *reporter,
 void
 devlink_health_reporter_recovery_done(struct devlink_health_reporter *reporter);
 
+int devl_nested_devlink_set(struct devlink *devlink,
+			    struct devlink *nested_devlink);
 bool devlink_is_reload_failed(const struct devlink *devlink);
 void devlink_remote_reload_actions_performed(struct devlink *devlink,
 					     enum devlink_reload_limit limit,
diff --git a/include/uapi/linux/devlink.h b/include/uapi/linux/devlink.h
index 03875e078be8..cd4b82458d1b 100644
--- a/include/uapi/linux/devlink.h
+++ b/include/uapi/linux/devlink.h
@@ -680,6 +680,7 @@ enum devlink_port_function_attr {
 	DEVLINK_PORT_FN_ATTR_STATE,	/* u8 */
 	DEVLINK_PORT_FN_ATTR_OPSTATE,	/* u8 */
 	DEVLINK_PORT_FN_ATTR_CAPS,	/* bitfield32 */
+	DEVLINK_PORT_FN_ATTR_DEVLINK,	/* nested */
 
 	__DEVLINK_PORT_FUNCTION_ATTR_MAX,
 	DEVLINK_PORT_FUNCTION_ATTR_MAX = __DEVLINK_PORT_FUNCTION_ATTR_MAX - 1
diff --git a/net/devlink/core.c b/net/devlink/core.c
index 6cec4afb01fb..bcbbb952569f 100644
--- a/net/devlink/core.c
+++ b/net/devlink/core.c
@@ -16,6 +16,219 @@ EXPORT_TRACEPOINT_SYMBOL_GPL(devlink_trap_report);
 
 DEFINE_XARRAY_FLAGS(devlinks, XA_FLAGS_ALLOC);
 
+static struct devlink *devlinks_xa_get(unsigned long index)
+{
+	struct devlink *devlink;
+
+	rcu_read_lock();
+	devlink = xa_find(&devlinks, &index, index, DEVLINK_REGISTERED);
+	if (!devlink || !devlink_try_get(devlink))
+		devlink = NULL;
+	rcu_read_unlock();
+	return devlink;
+}
+
+/* devlink_rels xarray contains 1:1 relationships between
+ * devlink object and related nested devlink instance.
+ * The xarray index is used to get the nested object from
+ * the nested-in object code.
+ */
+static DEFINE_XARRAY_FLAGS(devlink_rels, XA_FLAGS_ALLOC1);
+
+#define DEVLINK_REL_IN_USE XA_MARK_0
+
+struct devlink_rel {
+	u32 index;
+	refcount_t refcount;
+	u32 devlink_index;
+	struct {
+		u32 devlink_index;
+		u32 obj_index;
+		devlink_rel_notify_cb_t *notify_cb;
+		devlink_rel_cleanup_cb_t *cleanup_cb;
+		struct work_struct notify_work;
+	} nested_in;
+};
+
+static void devlink_rel_free(struct devlink_rel *rel)
+{
+	xa_erase(&devlink_rels, rel->index);
+	kfree(rel);
+}
+
+static void __devlink_rel_get(struct devlink_rel *rel)
+{
+	refcount_inc(&rel->refcount);
+}
+
+static void __devlink_rel_put(struct devlink_rel *rel)
+{
+	if (refcount_dec_and_test(&rel->refcount))
+		devlink_rel_free(rel);
+}
+
+static void devlink_rel_nested_in_notify_work(struct work_struct *work)
+{
+	struct devlink_rel *rel = container_of(work, struct devlink_rel,
+					       nested_in.notify_work);
+	struct devlink *devlink;
+
+	devlink = devlinks_xa_get(rel->nested_in.devlink_index);
+	if (!devlink)
+		goto rel_put;
+	if (!devl_trylock(devlink)) {
+		devlink_put(devlink);
+		goto reschedule_work;
+	}
+	if (!devl_is_registered(devlink)) {
+		devl_unlock(devlink);
+		devlink_put(devlink);
+		goto rel_put;
+	}
+	if (!xa_get_mark(&devlink_rels, rel->index, DEVLINK_REL_IN_USE))
+		rel->nested_in.cleanup_cb(devlink, rel->nested_in.obj_index, rel->index);
+	rel->nested_in.notify_cb(devlink, rel->nested_in.obj_index);
+	devl_unlock(devlink);
+	devlink_put(devlink);
+
+rel_put:
+	__devlink_rel_put(rel);
+	return;
+
+reschedule_work:
+	schedule_work(&rel->nested_in.notify_work);
+}
+
+static void devlink_rel_nested_in_notify_work_schedule(struct devlink_rel *rel)
+{
+	__devlink_rel_get(rel);
+	schedule_work(&rel->nested_in.notify_work);
+}
+
+static struct devlink_rel *devlink_rel_alloc(void)
+{
+	struct devlink_rel *rel;
+	static u32 next;
+	int err;
+
+	rel = kzalloc(sizeof(*rel), GFP_KERNEL);
+	if (!rel)
+		return ERR_PTR(-ENOMEM);
+
+	err = xa_alloc_cyclic(&devlink_rels, &rel->index, rel,
+			      xa_limit_32b, &next, GFP_KERNEL);
+	if (err) {
+		kfree(rel);
+		return ERR_PTR(err);
+	}
+
+	refcount_set(&rel->refcount, 1);
+	INIT_WORK(&rel->nested_in.notify_work,
+		  &devlink_rel_nested_in_notify_work);
+	return rel;
+}
+
+static void devlink_rel_put(struct devlink *devlink)
+{
+	struct devlink_rel *rel = devlink->rel;
+
+	if (!rel)
+		return;
+	xa_clear_mark(&devlink_rels, rel->index, DEVLINK_REL_IN_USE);
+	devlink_rel_nested_in_notify_work_schedule(rel);
+	__devlink_rel_put(rel);
+	devlink->rel = NULL;
+}
+
+void devlink_rel_nested_in_clear(u32 rel_index)
+{
+	xa_clear_mark(&devlink_rels, rel_index, DEVLINK_REL_IN_USE);
+}
+
+int devlink_rel_nested_in_add(u32 *rel_index, u32 devlink_index,
+			      u32 obj_index, devlink_rel_notify_cb_t *notify_cb,
+			      devlink_rel_cleanup_cb_t *cleanup_cb,
+			      struct devlink *devlink)
+{
+	struct devlink_rel *rel = devlink_rel_alloc();
+
+	ASSERT_DEVLINK_NOT_REGISTERED(devlink);
+
+	if (IS_ERR(rel))
+		return PTR_ERR(rel);
+
+	rel->devlink_index = devlink->index;
+	rel->nested_in.devlink_index = devlink_index;
+	rel->nested_in.obj_index = obj_index;
+	rel->nested_in.notify_cb = notify_cb;
+	rel->nested_in.cleanup_cb = cleanup_cb;
+	*rel_index = rel->index;
+	xa_set_mark(&devlink_rels, rel->index, DEVLINK_REL_IN_USE);
+	devlink->rel = rel;
+	return 0;
+}
+
+void devlink_rel_nested_in_notify(struct devlink *devlink)
+{
+	struct devlink_rel *rel = devlink->rel;
+
+	if (!rel)
+		return;
+	devlink_rel_nested_in_notify_work_schedule(rel);
+}
+
+static struct devlink_rel *devlink_rel_find(unsigned long rel_index)
+{
+	return xa_find(&devlink_rels, &rel_index, rel_index,
+		       DEVLINK_REL_IN_USE);
+}
+
+static struct devlink *devlink_rel_devlink_get_lock(u32 rel_index)
+{
+	struct devlink *devlink;
+	struct devlink_rel *rel;
+	u32 devlink_index;
+
+	if (!rel_index)
+		return NULL;
+	xa_lock(&devlink_rels);
+	rel = devlink_rel_find(rel_index);
+	if (rel)
+		devlink_index = rel->devlink_index;
+	xa_unlock(&devlink_rels);
+	if (!rel)
+		return NULL;
+	devlink = devlinks_xa_get(devlink_index);
+	if (!devlink)
+		return NULL;
+	devl_lock(devlink);
+	if (!devl_is_registered(devlink)) {
+		devl_unlock(devlink);
+		devlink_put(devlink);
+		return NULL;
+	}
+	return devlink;
+}
+
+int devlink_rel_devlink_handle_put(struct sk_buff *msg, struct devlink *devlink,
+				   u32 rel_index, int attrtype,
+				   bool *msg_updated)
+{
+	struct net *net = devlink_net(devlink);
+	struct devlink *rel_devlink;
+	int err;
+
+	rel_devlink = devlink_rel_devlink_get_lock(rel_index);
+	if (!rel_devlink)
+		return 0;
+	err = devlink_nl_put_nested_handle(msg, net, rel_devlink, attrtype);
+	devl_unlock(rel_devlink);
+	devlink_put(rel_devlink);
+	if (!err && msg_updated)
+		*msg_updated = true;
+	return err;
+}
+
 void *devlink_priv(struct devlink *devlink)
 {
 	return &devlink->priv;
@@ -142,6 +355,7 @@ int devl_register(struct devlink *devlink)
 
 	xa_set_mark(&devlinks, devlink->index, DEVLINK_REGISTERED);
 	devlink_notify_register(devlink);
+	devlink_rel_nested_in_notify(devlink);
 
 	return 0;
 }
@@ -166,6 +380,7 @@ void devl_unregister(struct devlink *devlink)
 
 	devlink_notify_unregister(devlink);
 	xa_clear_mark(&devlinks, devlink->index, DEVLINK_REGISTERED);
+	devlink_rel_put(devlink);
 }
 EXPORT_SYMBOL_GPL(devl_unregister);
 
@@ -215,6 +430,7 @@ struct devlink *devlink_alloc_ns(const struct devlink_ops *ops,
 	xa_init_flags(&devlink->ports, XA_FLAGS_ALLOC);
 	xa_init_flags(&devlink->params, XA_FLAGS_ALLOC);
 	xa_init_flags(&devlink->snapshot_ids, XA_FLAGS_ALLOC);
+	xa_init_flags(&devlink->nested_rels, XA_FLAGS_ALLOC);
 	write_pnet(&devlink->_net, net);
 	INIT_LIST_HEAD(&devlink->rate_list);
 	INIT_LIST_HEAD(&devlink->linecard_list);
@@ -261,6 +477,7 @@ void devlink_free(struct devlink *devlink)
 	WARN_ON(!list_empty(&devlink->linecard_list));
 	WARN_ON(!xa_empty(&devlink->ports));
 
+	xa_destroy(&devlink->nested_rels);
 	xa_destroy(&devlink->snapshot_ids);
 	xa_destroy(&devlink->params);
 	xa_destroy(&devlink->ports);
diff --git a/net/devlink/dev.c b/net/devlink/dev.c
index bba4ace7d22b..dc8039ca2b38 100644
--- a/net/devlink/dev.c
+++ b/net/devlink/dev.c
@@ -138,6 +138,23 @@ nla_put_failure:
 	return -EMSGSIZE;
 }
 
+static int devlink_nl_nested_fill(struct sk_buff *msg, struct devlink *devlink)
+{
+	unsigned long rel_index;
+	void *unused;
+	int err;
+
+	xa_for_each(&devlink->nested_rels, rel_index, unused) {
+		err = devlink_rel_devlink_handle_put(msg, devlink,
+						     rel_index,
+						     DEVLINK_ATTR_NESTED_DEVLINK,
+						     NULL);
+		if (err)
+			return err;
+	}
+	return 0;
+}
+
 static int devlink_nl_fill(struct sk_buff *msg, struct devlink *devlink,
 			   enum devlink_command cmd, u32 portid,
 			   u32 seq, int flags)
@@ -164,6 +181,10 @@ static int devlink_nl_fill(struct sk_buff *msg, struct devlink *devlink,
 		goto dev_stats_nest_cancel;
 
 	nla_nest_end(msg, dev_stats);
+
+	if (devlink_nl_nested_fill(msg, devlink))
+		goto nla_put_failure;
+
 	genlmsg_end(msg, hdr);
 	return 0;
 
@@ -230,6 +251,34 @@ int devlink_nl_get_dumpit(struct sk_buff *msg, struct netlink_callback *cb)
 	return devlink_nl_dumpit(msg, cb, devlink_nl_get_dump_one);
 }
 
+static void devlink_rel_notify_cb(struct devlink *devlink, u32 obj_index)
+{
+	devlink_notify(devlink, DEVLINK_CMD_NEW);
+}
+
+static void devlink_rel_cleanup_cb(struct devlink *devlink, u32 obj_index,
+				   u32 rel_index)
+{
+	xa_erase(&devlink->nested_rels, rel_index);
+}
+
+int devl_nested_devlink_set(struct devlink *devlink,
+			    struct devlink *nested_devlink)
+{
+	u32 rel_index;
+	int err;
+
+	err = devlink_rel_nested_in_add(&rel_index, devlink->index, 0,
+					devlink_rel_notify_cb,
+					devlink_rel_cleanup_cb,
+					nested_devlink);
+	if (err)
+		return err;
+	return xa_insert(&devlink->nested_rels, rel_index,
+			 xa_mk_value(0), GFP_KERNEL);
+}
+EXPORT_SYMBOL_GPL(devl_nested_devlink_set);
+
 void devlink_notify_register(struct devlink *devlink)
 {
 	devlink_notify(devlink, DEVLINK_CMD_NEW);
@@ -372,6 +421,7 @@ static void devlink_reload_netns_change(struct devlink *devlink,
 	devlink_notify_unregister(devlink);
 	write_pnet(&devlink->_net, dest_net);
 	devlink_notify_register(devlink);
+	devlink_rel_nested_in_notify(devlink);
 }
 
 int devlink_reload(struct devlink *devlink, struct net *dest_net,
diff --git a/net/devlink/devl_internal.h b/net/devlink/devl_internal.h
index f6b5fea2e13c..741d1bf1bec8 100644
--- a/net/devlink/devl_internal.h
+++ b/net/devlink/devl_internal.h
@@ -17,6 +17,8 @@
 
 #include "netlink_gen.h"
 
+struct devlink_rel;
+
 #define DEVLINK_REGISTERED XA_MARK_1
 
 #define DEVLINK_RELOAD_STATS_ARRAY_SIZE \
@@ -55,6 +57,8 @@ struct devlink {
 	u8 reload_failed:1;
 	refcount_t refcount;
 	struct rcu_work rwork;
+	struct devlink_rel *rel;
+	struct xarray nested_rels;
 	char priv[] __aligned(NETDEV_ALIGN);
 };
 
@@ -92,6 +96,20 @@ static inline bool devl_is_registered(struct devlink *devlink)
 	return xa_get_mark(&devlinks, devlink->index, DEVLINK_REGISTERED);
 }
 
+typedef void devlink_rel_notify_cb_t(struct devlink *devlink, u32 obj_index);
+typedef void devlink_rel_cleanup_cb_t(struct devlink *devlink, u32 obj_index,
+				      u32 rel_index);
+
+void devlink_rel_nested_in_clear(u32 rel_index);
+int devlink_rel_nested_in_add(u32 *rel_index, u32 devlink_index,
+			      u32 obj_index, devlink_rel_notify_cb_t *notify_cb,
+			      devlink_rel_cleanup_cb_t *cleanup_cb,
+			      struct devlink *devlink);
+void devlink_rel_nested_in_notify(struct devlink *devlink);
+int devlink_rel_devlink_handle_put(struct sk_buff *msg, struct devlink *devlink,
+				   u32 rel_index, int attrtype,
+				   bool *msg_updated);
+
 /* Netlink */
 #define DEVLINK_NL_FLAG_NEED_PORT		BIT(0)
 #define DEVLINK_NL_FLAG_NEED_DEVLINK_OR_PORT	BIT(1)
@@ -145,6 +163,8 @@ devlink_nl_put_handle(struct sk_buff *msg, struct devlink *devlink)
 	return 0;
 }
 
+int devlink_nl_put_nested_handle(struct sk_buff *msg, struct net *net,
+				 struct devlink *devlink, int attrtype);
 int devlink_nl_msg_reply_and_new(struct sk_buff **msg, struct genl_info *info);
 
 /* Notify */
@@ -206,19 +226,7 @@ int devlink_rate_nodes_check(struct devlink *devlink, u16 mode,
 			     struct netlink_ext_ack *extack);
 
 /* Linecards */
-struct devlink_linecard {
-	struct list_head list;
-	struct devlink *devlink;
-	unsigned int index;
-	const struct devlink_linecard_ops *ops;
-	void *priv;
-	enum devlink_linecard_state state;
-	struct mutex state_lock; /* Protects state */
-	const char *type;
-	struct devlink_linecard_type *types;
-	unsigned int types_count;
-	struct devlink *nested_devlink;
-};
+unsigned int devlink_linecard_index(struct devlink_linecard *linecard);
 
 /* Devlink nl cmds */
 int devlink_nl_cmd_reload(struct sk_buff *skb, struct genl_info *info);
diff --git a/net/devlink/linecard.c b/net/devlink/linecard.c
index 85c32c314b0f..9ff1813f88c5 100644
--- a/net/devlink/linecard.c
+++ b/net/devlink/linecard.c
@@ -6,6 +6,25 @@
 
 #include "devl_internal.h"
 
+struct devlink_linecard {
+	struct list_head list;
+	struct devlink *devlink;
+	unsigned int index;
+	const struct devlink_linecard_ops *ops;
+	void *priv;
+	enum devlink_linecard_state state;
+	struct mutex state_lock; /* Protects state */
+	const char *type;
+	struct devlink_linecard_type *types;
+	unsigned int types_count;
+	u32 rel_index;
+};
+
+unsigned int devlink_linecard_index(struct devlink_linecard *linecard)
+{
+	return linecard->index;
+}
+
 static struct devlink_linecard *
 devlink_linecard_get_by_index(struct devlink *devlink,
 			      unsigned int linecard_index)
@@ -46,24 +65,6 @@ devlink_linecard_get_from_info(struct devlink *devlink, struct genl_info *info)
 	return devlink_linecard_get_from_attrs(devlink, info->attrs);
 }
 
-static int devlink_nl_put_nested_handle(struct sk_buff *msg, struct devlink *devlink)
-{
-	struct nlattr *nested_attr;
-
-	nested_attr = nla_nest_start(msg, DEVLINK_ATTR_NESTED_DEVLINK);
-	if (!nested_attr)
-		return -EMSGSIZE;
-	if (devlink_nl_put_handle(msg, devlink))
-		goto nla_put_failure;
-
-	nla_nest_end(msg, nested_attr);
-	return 0;
-
-nla_put_failure:
-	nla_nest_cancel(msg, nested_attr);
-	return -EMSGSIZE;
-}
-
 struct devlink_linecard_type {
 	const char *type;
 	const void *priv;
@@ -111,8 +112,10 @@ static int devlink_nl_linecard_fill(struct sk_buff *msg,
 		nla_nest_end(msg, attr);
 	}
 
-	if (linecard->nested_devlink &&
-	    devlink_nl_put_nested_handle(msg, linecard->nested_devlink))
+	if (devlink_rel_devlink_handle_put(msg, devlink,
+					   linecard->rel_index,
+					   DEVLINK_ATTR_NESTED_DEVLINK,
+					   NULL))
 		goto nla_put_failure;
 
 	genlmsg_end(msg, hdr);
@@ -521,7 +524,6 @@ EXPORT_SYMBOL_GPL(devlink_linecard_provision_set);
 void devlink_linecard_provision_clear(struct devlink_linecard *linecard)
 {
 	mutex_lock(&linecard->state_lock);
-	WARN_ON(linecard->nested_devlink);
 	linecard->state = DEVLINK_LINECARD_STATE_UNPROVISIONED;
 	linecard->type = NULL;
 	devlink_linecard_notify(linecard, DEVLINK_CMD_LINECARD_NEW);
@@ -540,7 +542,6 @@ EXPORT_SYMBOL_GPL(devlink_linecard_provision_clear);
 void devlink_linecard_provision_fail(struct devlink_linecard *linecard)
 {
 	mutex_lock(&linecard->state_lock);
-	WARN_ON(linecard->nested_devlink);
 	linecard->state = DEVLINK_LINECARD_STATE_PROVISIONING_FAILED;
 	devlink_linecard_notify(linecard, DEVLINK_CMD_LINECARD_NEW);
 	mutex_unlock(&linecard->state_lock);
@@ -588,6 +589,27 @@ void devlink_linecard_deactivate(struct devlink_linecard *linecard)
 }
 EXPORT_SYMBOL_GPL(devlink_linecard_deactivate);
 
+static void devlink_linecard_rel_notify_cb(struct devlink *devlink,
+					   u32 linecard_index)
+{
+	struct devlink_linecard *linecard;
+
+	linecard = devlink_linecard_get_by_index(devlink, linecard_index);
+	if (!linecard)
+		return;
+	devlink_linecard_notify(linecard, DEVLINK_CMD_LINECARD_NEW);
+}
+
+static void devlink_linecard_rel_cleanup_cb(struct devlink *devlink,
+					    u32 linecard_index, u32 rel_index)
+{
+	struct devlink_linecard *linecard;
+
+	linecard = devlink_linecard_get_by_index(devlink, linecard_index);
+	if (linecard && linecard->rel_index == rel_index)
+		linecard->rel_index = 0;
+}
+
 /**
  *	devlink_linecard_nested_dl_set - Attach/detach nested devlink
  *					 instance to linecard.
@@ -595,12 +617,14 @@ EXPORT_SYMBOL_GPL(devlink_linecard_deactivate);
  *	@linecard: devlink linecard
  *	@nested_devlink: devlink instance to attach or NULL to detach
  */
-void devlink_linecard_nested_dl_set(struct devlink_linecard *linecard,
-				    struct devlink *nested_devlink)
+int devlink_linecard_nested_dl_set(struct devlink_linecard *linecard,
+				   struct devlink *nested_devlink)
 {
-	mutex_lock(&linecard->state_lock);
-	linecard->nested_devlink = nested_devlink;
-	devlink_linecard_notify(linecard, DEVLINK_CMD_LINECARD_NEW);
-	mutex_unlock(&linecard->state_lock);
+	return devlink_rel_nested_in_add(&linecard->rel_index,
+					 linecard->devlink->index,
+					 linecard->index,
+					 devlink_linecard_rel_notify_cb,
+					 devlink_linecard_rel_cleanup_cb,
+					 nested_devlink);
 }
 EXPORT_SYMBOL_GPL(devlink_linecard_nested_dl_set);
diff --git a/net/devlink/netlink.c b/net/devlink/netlink.c
index fc3e7c029a3b..499304d9de49 100644
--- a/net/devlink/netlink.c
+++ b/net/devlink/netlink.c
@@ -82,6 +82,32 @@ static const struct nla_policy devlink_nl_policy[DEVLINK_ATTR_MAX + 1] = {
 	[DEVLINK_ATTR_REGION_DIRECT] = { .type = NLA_FLAG },
 };
 
+int devlink_nl_put_nested_handle(struct sk_buff *msg, struct net *net,
+				 struct devlink *devlink, int attrtype)
+{
+	struct nlattr *nested_attr;
+
+	nested_attr = nla_nest_start(msg, attrtype);
+	if (!nested_attr)
+		return -EMSGSIZE;
+	if (devlink_nl_put_handle(msg, devlink))
+		goto nla_put_failure;
+	if (!net_eq(net, devlink_net(devlink))) {
+		int id = peernet2id_alloc(net, devlink_net(devlink),
+					  GFP_KERNEL);
+
+		if (nla_put_s32(msg, DEVLINK_ATTR_NETNS_ID, id))
+			return -EMSGSIZE;
+	}
+
+	nla_nest_end(msg, nested_attr);
+	return 0;
+
+nla_put_failure:
+	nla_nest_cancel(msg, nested_attr);
+	return -EMSGSIZE;
+}
+
 int devlink_nl_msg_reply_and_new(struct sk_buff **msg, struct genl_info *info)
 {
 	int err;
diff --git a/net/devlink/port.c b/net/devlink/port.c
index 4763b42885fb..4e9003242448 100644
--- a/net/devlink/port.c
+++ b/net/devlink/port.c
@@ -428,6 +428,13 @@ devlink_nl_port_function_attrs_put(struct sk_buff *msg, struct devlink_port *por
 	if (err)
 		goto out;
 	err = devlink_port_fn_state_fill(port, msg, extack, &msg_updated);
+	if (err)
+		goto out;
+	err = devlink_rel_devlink_handle_put(msg, port->devlink,
+					     port->rel_index,
+					     DEVLINK_PORT_FN_ATTR_DEVLINK,
+					     &msg_updated);
+
 out:
 	if (err || !msg_updated)
 		nla_nest_cancel(msg, function_attr);
@@ -483,7 +490,7 @@ static int devlink_nl_port_fill(struct sk_buff *msg,
 		goto nla_put_failure;
 	if (devlink_port->linecard &&
 	    nla_put_u32(msg, DEVLINK_ATTR_LINECARD_INDEX,
-			devlink_port->linecard->index))
+			devlink_linecard_index(devlink_port->linecard)))
 		goto nla_put_failure;
 
 	genlmsg_end(msg, hdr);
@@ -1392,6 +1399,50 @@ void devlink_port_attrs_pci_sf_set(struct devlink_port *devlink_port, u32 contro
 }
 EXPORT_SYMBOL_GPL(devlink_port_attrs_pci_sf_set);
 
+static void devlink_port_rel_notify_cb(struct devlink *devlink, u32 port_index)
+{
+	struct devlink_port *devlink_port;
+
+	devlink_port = devlink_port_get_by_index(devlink, port_index);
+	if (!devlink_port)
+		return;
+	devlink_port_notify(devlink_port, DEVLINK_CMD_PORT_NEW);
+}
+
+static void devlink_port_rel_cleanup_cb(struct devlink *devlink, u32 port_index,
+					u32 rel_index)
+{
+	struct devlink_port *devlink_port;
+
+	devlink_port = devlink_port_get_by_index(devlink, port_index);
+	if (devlink_port && devlink_port->rel_index == rel_index)
+		devlink_port->rel_index = 0;
+}
+
+/**
+ * devl_port_fn_devlink_set - Attach peer devlink
+ *			      instance to port function.
+ * @devlink_port: devlink port
+ * @fn_devlink: devlink instance to attach
+ */
+int devl_port_fn_devlink_set(struct devlink_port *devlink_port,
+			     struct devlink *fn_devlink)
+{
+	ASSERT_DEVLINK_PORT_REGISTERED(devlink_port);
+
+	if (WARN_ON(devlink_port->attrs.flavour != DEVLINK_PORT_FLAVOUR_PCI_SF ||
+		    devlink_port->attrs.pci_sf.external))
+		return -EINVAL;
+
+	return devlink_rel_nested_in_add(&devlink_port->rel_index,
+					 devlink_port->devlink->index,
+					 devlink_port->index,
+					 devlink_port_rel_notify_cb,
+					 devlink_port_rel_cleanup_cb,
+					 fn_devlink);
+}
+EXPORT_SYMBOL_GPL(devl_port_fn_devlink_set);
+
 /**
  *	devlink_port_linecard_set - Link port with a linecard
  *
@@ -1420,7 +1471,7 @@ static int __devlink_port_phys_port_name_get(struct devlink_port *devlink_port,
 	case DEVLINK_PORT_FLAVOUR_PHYSICAL:
 		if (devlink_port->linecard)
 			n = snprintf(name, len, "l%u",
-				     devlink_port->linecard->index);
+				     devlink_linecard_index(devlink_port->linecard));
 		if (n < len)
 			n += snprintf(name + n, len - n, "p%u",
 				      attrs->phys.port_number);