[PATCH] ppc64 need HPAGE_SHIFT when huge pages disabled

With the new powerpc architecture we don't seem to be able to disable huge
pages anymore.

    mm/built-in.o(.toc1+0xae0): undefined reference to `HPAGE_SHIFT'
    make: *** [.tmp_vmlinux1] Error 1

We seem to need to define HPAGE_SHIFT to something when HUGETLB_PAGE isn't
defined.  This patch defines it to PAGE_SHIFT when we have no support.

Signed-off-by: Andy Whitcroft <apw@shadowen.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

include/asm-powerpc/page_64.h

@@ -86,7 +86,11 @@ static inline void copy_page(void *to, void *from)
 extern u64 ppc64_pft_size;
 
 /* Large pages size */
+#ifdef CONFIG_HUGETLB_PAGE
 extern unsigned int HPAGE_SHIFT;
+#else
+#define HPAGE_SHIFT PAGE_SHIFT
+#endif
 #define HPAGE_SIZE		((1UL) << HPAGE_SHIFT)
 #define HPAGE_MASK		(~(HPAGE_SIZE - 1))
 #define HUGETLB_PAGE_ORDER	(HPAGE_SHIFT - PAGE_SHIFT)