[PATCH] uml: make 64-bit COW files compatible with 32-bit ones

This is the minimal fix to make 64-bit UML binaries create 32-bit
compatible COW files and read them.

I've indeed tested that current code doesn't do this - the code gets
SIGFPE for a division by a value read at the wrong place, where 0 is
found.

Signed-off-by: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
Cc: Jeff Dike <jdike@addtoit.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>