[BusyBox] losetup and loop

[Magnus Damm]

Hi girls and boys,

I would like to mount my root fs on a fsimage which is located on a
disk.
This could be done pretty easy using a kernel with ROOT fs on the
loopdevice,
and an initrd that mounts a disk somewhere and setups /dev/loop0 to a
fsimage.

I had a look at the The "Loopback Root Filesystem HOWTO":

http://www.gedanken.demon.co.uk/linux/looproot.html

According to the example of a "/linuxrc" file the HOWTO suggests
to use "losetup" to setup /dev/loop0 to a fsimage on disk.

I would like to implement this using only a static busybox.
Why is there no losetup in busybox?
I mean, I found some matches to an old removed losetup..
And I've used the buysbox mount to mount via loopdevices...
What's up?

Maybe I could implement this using mount + chroot?

TIA /

Magnus