$6.$ Since the Unix file system uses several types of indirect blocks $($e$.$g$.,$ single indirect, double indirect, etc.$)$ to store metadata information of large files, accessing a large file requires accessing several additional indirect blocks. Therefore, the Soongsil University Operating System Research Lab developed SSUFS, an extent$-$based file system, to reduce metadata storage and access overhead. An extent consists of a series of consecutive sectors on the disk, and the file system represents i$-$nodes in the following manner.

$```$

#define NEXTENT $12$

struct SSUFS$\_$inode$\{$

uint$64\_$t filesize;

uint$64\_$t nlink;

uint$32\_$t extent$\_$size;

uint$32\_$t extents$[$NEXTENT$]$;

$\}$

$```$