4.0 ice cream sandwich - Internal hard disk partitions (sda2) not showing in android system

I have a x86 system (Asus Eee Pc)having hard disk of 232 GB, in which 4 GB allocated for Android and rest I don't know where it is gone. If I open super user and running this command in android terminal: cat /proc/partitions I get following result:

Block_Size(232Gb) sda

Block_Size(4Gb) sda1
Block_Size(rest) sda2

This shows there are two partitions (sda1, sda2) of total 1 drive (sda). Android is installed in sda1 and seen in it's file system. But sda2 data is invisible. When i run mount command , we get :

• rootfs /rootfs rw 0 0


• proc /proc proc rw ,relatime 0 0


• /dev/sda1 /mnt ext3 rw,relatime,error=continue,barrier=0,data=writeback 0 0


• few lines .... But nothing about sda2 .

I also try #busybox fdisk -l /dev/block/sda

   Device Boot     start   End     Blocks  Id  System

• /dev/block/sda1 1 528 4241128+ 83 Linux


• /dev/block/sda2 529 30396 23914716 83 Linux


• /dev/block/sda3 30397 30402 42714 ef EFI(FAT-12/16/32)

And when i run

-#busybox fdisk -l /dev/block/sda2 result is : - doesn't contain a valid partition table .

How can I mount this drive in android? I just want to access and view the sda2 storage drive.