1 files changed, 123 insertions, 2 deletions

diff --git a/net/core/devlink.c b/net/core/devlink.c
index 589d750b70e4..464f56408247 100644
--- a/net/core/devlink.c
+++ b/net/core/devlink.c
@@ -880,6 +880,11 @@ static int devlink_nl_rate_fill(struct sk_buff *msg,
 			      devlink_rate->tx_max, DEVLINK_ATTR_PAD))
 		goto nla_put_failure;
 
+	if (devlink_rate->parent)
+		if (nla_put_string(msg, DEVLINK_ATTR_RATE_PARENT_NODE_NAME,
+				   devlink_rate->parent->name))
+			goto nla_put_failure;
+
 	genlmsg_end(msg, hdr);
 	return 0;
 
@@ -1152,6 +1157,18 @@ static int devlink_nl_cmd_rate_get_doit(struct sk_buff *skb,
 	return genlmsg_reply(msg, info);
 }
 
+static bool
+devlink_rate_is_parent_node(struct devlink_rate *devlink_rate,
+			    struct devlink_rate *parent)
+{
+	while (parent) {
+		if (parent == devlink_rate)
+			return true;
+		parent = parent->parent;
+	}
+	return false;
+}
+
 static int devlink_nl_cmd_get_doit(struct sk_buff *skb, struct genl_info *info)
 {
 	struct devlink *devlink = info->user_ptr[0];
@@ -1572,11 +1589,75 @@ static int devlink_nl_cmd_port_del_doit(struct sk_buff *skb,
 	return devlink->ops->port_del(devlink, port_index, extack);
 }
 
+static int
+devlink_nl_rate_parent_node_set(struct devlink_rate *devlink_rate,
+				struct genl_info *info,
+				struct nlattr *nla_parent)
+{
+	struct devlink *devlink = devlink_rate->devlink;
+	const char *parent_name = nla_data(nla_parent);
+	const struct devlink_ops *ops = devlink->ops;
+	size_t len = strlen(parent_name);
+	struct devlink_rate *parent;
+	int err = -EOPNOTSUPP;
+
+	parent = devlink_rate->parent;
+	if (parent && len) {
+		NL_SET_ERR_MSG_MOD(info->extack, "Rate object already has parent.");
+		return -EBUSY;
+	} else if (parent && !len) {
+		if (devlink_rate_is_leaf(devlink_rate))
+			err = ops->rate_leaf_parent_set(devlink_rate, NULL,
+							devlink_rate->priv, NULL,
+							info->extack);
+		else if (devlink_rate_is_node(devlink_rate))
+			err = ops->rate_node_parent_set(devlink_rate, NULL,
+							devlink_rate->priv, NULL,
+							info->extack);
+		if (err)
+			return err;
+
+		refcount_dec(&parent->refcnt);
+		devlink_rate->parent = NULL;
+	} else if (!parent && len) {
+		parent = devlink_rate_node_get_by_name(devlink, parent_name);
+		if (IS_ERR(parent))
+			return -ENODEV;
+
+		if (parent == devlink_rate) {
+			NL_SET_ERR_MSG_MOD(info->extack, "Parent to self is not allowed");
+			return -EINVAL;
+		}
+
+		if (devlink_rate_is_node(devlink_rate) &&
+		    devlink_rate_is_parent_node(devlink_rate, parent->parent)) {
+			NL_SET_ERR_MSG_MOD(info->extack, "Node is already a parent of parent node.");
+			return -EEXIST;
+		}
+
+		if (devlink_rate_is_leaf(devlink_rate))
+			err = ops->rate_leaf_parent_set(devlink_rate, parent,
+							devlink_rate->priv, parent->priv,
+							info->extack);
+		else if (devlink_rate_is_node(devlink_rate))
+			err = ops->rate_node_parent_set(devlink_rate, parent,
+							devlink_rate->priv, parent->priv,
+							info->extack);
+		if (err)
+			return err;
+
+		refcount_inc(&parent->refcnt);
+		devlink_rate->parent = parent;
+	}
+
+	return 0;
+}
+
 static int devlink_nl_rate_set(struct devlink_rate *devlink_rate,
 			       const struct devlink_ops *ops,
 			       struct genl_info *info)
 {
-	struct nlattr **attrs = info->attrs;
+	struct nlattr *nla_parent, **attrs = info->attrs;
 	int err = -EOPNOTSUPP;
 	u64 rate;
 
@@ -1606,6 +1687,14 @@ static int devlink_nl_rate_set(struct devlink_rate *devlink_rate,
 		devlink_rate->tx_max = rate;
 	}
 
+	nla_parent = attrs[DEVLINK_ATTR_RATE_PARENT_NODE_NAME];
+	if (nla_parent) {
+		err = devlink_nl_rate_parent_node_set(devlink_rate, info,
+						      nla_parent);
+		if (err)
+			return err;
+	}
+
 	return 0;
 }
 
@@ -1624,6 +1713,11 @@ static bool devlink_rate_set_ops_supported(const struct devlink_ops *ops,
 			NL_SET_ERR_MSG_MOD(info->extack, "TX max set isn't supported for the leafs");
 			return false;
 		}
+		if (attrs[DEVLINK_ATTR_RATE_PARENT_NODE_NAME] &&
+		    !ops->rate_leaf_parent_set) {
+			NL_SET_ERR_MSG_MOD(info->extack, "Parent set isn't supported for the leafs");
+			return false;
+		}
 	} else if (type == DEVLINK_RATE_TYPE_NODE) {
 		if (attrs[DEVLINK_ATTR_RATE_TX_SHARE] && !ops->rate_node_tx_share_set) {
 			NL_SET_ERR_MSG_MOD(info->extack, "TX share set isn't supported for the nodes");
@@ -1633,6 +1727,11 @@ static bool devlink_rate_set_ops_supported(const struct devlink_ops *ops,
 			NL_SET_ERR_MSG_MOD(info->extack, "TX max set isn't supported for the nodes");
 			return false;
 		}
+		if (attrs[DEVLINK_ATTR_RATE_PARENT_NODE_NAME] &&
+		    !ops->rate_node_parent_set) {
+			NL_SET_ERR_MSG_MOD(info->extack, "Parent set isn't supported for the nodes");
+			return false;
+		}
 	} else {
 		WARN_ON("Unknown type of rate object");
 		return false;
@@ -1702,6 +1801,7 @@ static int devlink_nl_cmd_rate_new_doit(struct sk_buff *skb,
 	if (err)
 		goto err_rate_set;
 
+	refcount_set(&rate_node->refcnt, 1);
 	list_add(&rate_node->list, &devlink->rate_list);
 	devlink_rate_notify(rate_node, DEVLINK_CMD_RATE_NEW);
 	return 0;
@@ -1723,8 +1823,15 @@ static int devlink_nl_cmd_rate_del_doit(struct sk_buff *skb,
 	const struct devlink_ops *ops = devlink->ops;
 	int err;
 
+	if (refcount_read(&rate_node->refcnt) > 1) {
+		NL_SET_ERR_MSG_MOD(info->extack, "Node has children. Cannot delete node.");
+		return -EBUSY;
+	}
+
 	devlink_rate_notify(rate_node, DEVLINK_CMD_RATE_DEL);
 	err = ops->rate_node_del(rate_node, rate_node->priv, info->extack);
+	if (rate_node->parent)
+		refcount_dec(&rate_node->parent->refcnt);
 	list_del(&rate_node->list);
 	kfree(rate_node->name);
 	kfree(rate_node);
@@ -8224,6 +8331,7 @@ static const struct nla_policy devlink_nl_policy[DEVLINK_ATTR_MAX + 1] = {
 	[DEVLINK_ATTR_RATE_TX_SHARE] = { .type = NLA_U64 },
 	[DEVLINK_ATTR_RATE_TX_MAX] = { .type = NLA_U64 },
 	[DEVLINK_ATTR_RATE_NODE_NAME] = { .type = NLA_NUL_STRING },
+	[DEVLINK_ATTR_RATE_PARENT_NODE_NAME] = { .type = NLA_NUL_STRING },
 };
 
 static const struct genl_small_ops devlink_nl_ops[] = {
@@ -9135,7 +9243,8 @@ EXPORT_SYMBOL_GPL(devlink_rate_leaf_destroy);
  *
  * @devlink: devlink instance
  *
- * Destroy all rate nodes on specified device
+ * Unset parent for all rate objects and destroy all rate nodes
+ * on specified device.
  *
  * Context: Takes and release devlink->lock <mutex>.
  */
@@ -9145,6 +9254,18 @@ void devlink_rate_nodes_destroy(struct devlink *devlink)
 	const struct devlink_ops *ops = devlink->ops;
 
 	mutex_lock(&devlink->lock);
+	list_for_each_entry(devlink_rate, &devlink->rate_list, list) {
+		if (!devlink_rate->parent)
+			continue;
+
+		refcount_dec(&devlink_rate->parent->refcnt);
+		if (devlink_rate_is_leaf(devlink_rate))
+			ops->rate_leaf_parent_set(devlink_rate, NULL, devlink_rate->priv,
+						  NULL, NULL);
+		else if (devlink_rate_is_node(devlink_rate))
+			ops->rate_node_parent_set(devlink_rate, NULL, devlink_rate->priv,
+						  NULL, NULL);
+	}
 	list_for_each_entry_safe(devlink_rate, tmp, &devlink->rate_list, list) {
 		if (devlink_rate_is_node(devlink_rate)) {
 			ops->rate_node_del(devlink_rate, devlink_rate->priv, NULL);