如何在rust中正确返回对变异链表的引用？

use std::cell::RefCell;
use std::rc::Rc;

struct LinkedList {
    head: Option<Rc<RefCell<Node>>>,
}

struct Node {
    data: i32,
    next: Option<Rc<RefCell<Node>>>,
}

impl LinkedList {
    // 添加节点
    fn add_node(&mut self, data: i32) {
        let new_node = Rc::new(RefCell::new(Node {
            data: data,
            next: None,
        }));

        if let Some(ref mut head) = self.head {
            let mut current = head.borrow_mut();
            while let Some(ref mut next) = current.next {
                current = next.borrow_mut();
            }
            current.next = Some(Rc::clone(&new_node));
        } else {
            self.head = Some(new_node);
        }
    }

    // 删除节点
    fn remove_node(&mut self, data: i32) {
        if let Some(ref mut head) = self.head {
            let mut current = head.borrow_mut();
            let mut prev = None;

            while let Some(ref mut node) = current.next {
                if node.borrow().data == data {
                    if let Some(ref mut next) = node.borrow_mut().next {
                        current.next = Some(Rc::clone(&next));
                    } else {
                        current.next = None;
                    }
                    break;
                }
                prev = Some(Rc::clone(&current));
                current = node.borrow_mut();
            }

            if let Some(ref mut prev) = prev {
                prev.borrow_mut().next = current.next.clone();
            } else {
                self.head = current.next.clone();
            }
        }
    }
}