From: Arnd Bergmann <arnd@arndb.de>
Date: Fri, 15 Jun 2007 11:31:37 +0200

One common problem with 32 bit system call and ioctl emulation
is the different alignment rules between i386 and 64 bit machines.
A number of drivers work around this by marking the compat
structures as 'attribute((packed))', which is not the right
solution because it breaks all the non-x86 architectures that
want to use the same compat code.

Hopefully, this patch improves the situation, it introduces two
new types, compat_u64 and compat_s64. These are defined on all
architectures to have the same size and alignment as the 32 bit
version of u64 and s64.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>

Acked-by: David S. Miller <davem@davemloft.net>