mm: add missing __PAGETABLE_{PUD,PMD}_FOLDED defines

Core mm expects __PAGETABLE_{PUD,PMD}_FOLDED to be defined if these page
table levels folded.  Usually, these defines are provided by
<asm-generic/pgtable-nopmd.h> and <asm-generic/pgtable-nopud.h>.

But some architectures fold page table levels in a custom way.  They
need to define these macros themself.  This patch adds missing defines.

The patch fixes mm->nr_pmds underflow and eliminates dead __pmd_alloc()
and __pud_alloc() on architectures without these page table levels.

Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Aaro Koskinen <aaro.koskinen@iki.fi>
Cc: David Howells <dhowells@redhat.com>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Helge Deller <deller@gmx.de>
Cc: "James E.J. Bottomley" <jejb@parisc-linux.org>
Cc: Koichi Yasutake <yasutake.koichi@jp.panasonic.com>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

1 files changed, 2 insertions, 0 deletions

diff --git a/arch/frv/include/asm/pgtable.h b/arch/frv/include/asm/pgtable.h
index 93bcf2abd1a1..07d7a7ef8bd5 100644
--- a/arch/frv/include/asm/pgtable.h
+++ b/arch/frv/include/asm/pgtable.h
@@ -123,12 +123,14 @@ extern unsigned long empty_zero_page;
 #define PGDIR_MASK              (~(PGDIR_SIZE - 1))
 #define PTRS_PER_PGD            64
 
+#define __PAGETABLE_PUD_FOLDED
 #define PUD_SHIFT               26
 #define PTRS_PER_PUD            1
 #define PUD_SIZE                (1UL << PUD_SHIFT)
 #define PUD_MASK                (~(PUD_SIZE - 1))
 #define PUE_SIZE                256
 
+#define __PAGETABLE_PMD_FOLDED
 #define PMD_SHIFT               26
 #define PMD_SIZE                (1UL << PMD_SHIFT)
 #define PMD_MASK                (~(PMD_SIZE - 1))