Don't test a pointer against 0. Use NULL instead.
Signed-off-by: NJiri Slaby <jirislaby@gmail.com>
Reviewed-by: NAlan Cox <alan@redhat.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>