There is no need to perform a separate losetup step; mount (even
the one in busybox!) is smart enough to set up a loopback device
all by itself (even without -o loop present!). More to say, while
doing this, it sets LO_FLAGS_AUTOCLEAR flag for the kernel to
delete the loopback device as soon as its fs is unmounted (this
is supposed to work since kernel 2.6.25).
Also, remove mount options (-t ext4, -o loop,rw) as they are
either defaults (rw) or mount is smart enough to figure out.
Leave -n so it won't do unnecessary write to container's /etc/mtab.
While at it, touch up some comments.
Signed-off-by: Kir Kolyshkin <kolyshkin@gmail.com>
Upstream-commit: a978fd22daefcc68d37c46177a545f7e1dfc6d9e
Component: engine
fe76970085