x86: Add NMI types for kmap_atomic

Two new kmap_atomic slots for NMI context. And teach pte_offset_map()
about NMI context.

Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
CC: Nick Piggin <npiggin@suse.de>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

arch/x86/include/asm/kmap_types.h

@@ -21,7 +21,9 @@ D(9)	KM_IRQ0,
 D(10)	KM_IRQ1,
 D(11)	KM_SOFTIRQ0,
 D(12)	KM_SOFTIRQ1,
-D(13)	KM_TYPE_NR
+D(13)	KM_NMI,
+D(14)	KM_NMI_PTE,
+D(15)	KM_TYPE_NR
 };
 
 #undef D

arch/x86/include/asm/pgtable_32.h

@@ -49,13 +49,14 @@ extern void set_pmd_pfn(unsigned long, unsigned long, pgprot_t);
 #endif
 
 #if defined(CONFIG_HIGHPTE)
+#define __KM_PTE	(in_nmi() ? KM_NMI_PTE : KM_PTE0)
 #define pte_offset_map(dir, address)					\
-	((pte_t *)kmap_atomic_pte(pmd_page(*(dir)), KM_PTE0) +		\
+	((pte_t *)kmap_atomic_pte(pmd_page(*(dir)), __KM_PTE) +		\
 	 pte_index((address)))
 #define pte_offset_map_nested(dir, address)				\
 	((pte_t *)kmap_atomic_pte(pmd_page(*(dir)), KM_PTE1) +		\
 	 pte_index((address)))
-#define pte_unmap(pte) kunmap_atomic((pte), KM_PTE0)
+#define pte_unmap(pte) kunmap_atomic((pte), __KM_PTE)
 #define pte_unmap_nested(pte) kunmap_atomic((pte), KM_PTE1)
 #else
 #define pte_offset_map(dir, address)					\