x86: Add NMI types for kmap_atomic, fix

I just realized this has a kmap_atomic bug in...

The below would fix it - but it's complicating this code
some more.

Alternatively I would have to introduce something like
pte_offset_map_irq() which would make the irq/nmi detection and leave
the regular code paths alone, however that would mean either duplicating
the gup_fast() pagewalk or passing down a pte function pointer, which
would only duplicate the gup_pte_range() bit, neither is really
attractive ...

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

@@ -19,11 +19,12 @@ D(7)	KM_PTE0,
 D(8)	KM_PTE1,
 D(9)	KM_IRQ0,
 D(10)	KM_IRQ1,
-D(11)	KM_SOFTIRQ0,
-D(12)	KM_SOFTIRQ1,
-D(13)	KM_NMI,
-D(14)	KM_NMI_PTE,
-D(15)	KM_TYPE_NR
+D(11)	KM_IRQ_PTE,
+D(12)	KM_SOFTIRQ0,
+D(13)	KM_SOFTIRQ1,
+D(14)	KM_NMI,
+D(15)	KM_NMI_PTE,
+D(16)	KM_TYPE_NR
 };
 
 #undef D

arch/x86/include/asm/pgtable_32.h

@@ -49,7 +49,10 @@ 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 __KM_PTE			\
+	(in_nmi() ? KM_NMI_PTE : 	\
+	 in_irq() ? KM_IRQ_PTE :	\
+	 KM_PTE0)
 #define pte_offset_map(dir, address)					\
 	((pte_t *)kmap_atomic_pte(pmd_page(*(dir)), __KM_PTE) +		\
 	 pte_index((address)))