fs_cblkno         195 ufs/ffs/fs.h   	int32_t	 fs_cblkno;		/* offset of cyl-block / frags */
fs_cblkno         470 ufs/ffs/fs.h   #define	cgtod(fs, c)	(cgstart(fs, c) + (fs)->fs_cblkno)	/* cg block */