Simple and stupid - just use the same code from another place in the kernel.

Signed-off-by: Pavel Emelianov <xemul@openvz.org>
Acked-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>