核心，利用mmap进行映射

参考资料

uio 编写实例 1 https://blog.csdn.net/wujiangguizhen/article/details/12453253
uio编写实例 2 https://blog.csdn.net/sunjing_/article/details/74725976
https://blog.csdn.net/lsz137105/article/details/100588871