cannot mount sdext for link2sd? I have a huawei u8160 running Cyanogenmod 7.2.

when I restart my phone I have to remount the sdext myself using terminal emulator.

su
mount -t ext2 /dev/block/mmcblk0p2 /data/sdext2


but now it returns :

mount : mounting /dev/block/mmcblk0p2 on /data/sdext2 failed : invalid argument


so I want to know how can I mount it again?
I've found it out,

the ext2 partition magically turned into ext3 without formatting I don't know how but it happened,

Formatted my ext3 partition into ext2 again and it worked,I couldn't find anyway to bring lost data back.