Insertion Sort List (LeetCode)

Sort a linked list using insertion sort.

public ListNode insertionSortList(ListNode head) {        if(head==null)            return null;        ListNode small = head, large = head, run = head.next;        while(run!=null){            if(run.val <= small.val){                large.next = run.next;                run.next = small;                small = run;                run = large.next;            }            else if(run.val >=large.val){                large = run;                run = run.next;            }            else{                ListNode tmp = small;                while(tmp.next.val < run.val)                        tmp = tmp.next;                large.next=run.next;                run.next = tmp.next;                tmp.next = run;                run = large.next;            }        }        return small;    }