drivers/pci/intel-iommu.c: fix build with older gcc's

drivers/pci/intel-iommu.c: In function `__iommu_calculate_agaw':
drivers/pci/intel-iommu.c:437: sorry, unimplemented: inlining failed in call to 'width_to_agaw': function body not available
drivers/pci/intel-iommu.c:445: sorry, unimplemented: called from here

Move the offending function (and its siblings) to top-of-file, remove the
forward declaration.

Addresses https://bugzilla.kernel.org/show_bug.cgi?id=17441

Reported-by: Martin Mokrejs <[e-mail]>
Cc: David Woodhouse <[e-mail]>
Cc: Jesse Barnes <[e-mail]>
Cc: <[e-mail]>
Signed-off-by: Andrew Morton <[e-mail]>
Signed-off-by: Linus Torvalds <[e-mail]>

drivers/pci/intel-iommu.c

···
 #define DMA_32BIT_PFN		IOVA_PFN(DMA_BIT_MASK(32))
 #define DMA_64BIT_PFN		IOVA_PFN(DMA_BIT_MASK(64))
 
+/* page table handling */
+#define LEVEL_STRIDE		(9)
+#define LEVEL_MASK		(((u64)1 << LEVEL_STRIDE) - 1)
+
+static inline int agaw_to_level(int agaw)
+{
+	return agaw + 2;
+}
+
+static inline int agaw_to_width(int agaw)
+{
+	return 30 + agaw * LEVEL_STRIDE;
+}
+
+static inline int width_to_agaw(int width)
+{
+	return (width - 30) / LEVEL_STRIDE;
+}
+
+static inline unsigned int level_to_offset_bits(int level)
+{
+	return (level - 1) * LEVEL_STRIDE;
+}
+
+static inline int pfn_level_offset(unsigned long pfn, int level)
+{
+	return (pfn >> level_to_offset_bits(level)) & LEVEL_MASK;
+}
+
+static inline unsigned long level_mask(int level)
+{
+	return -1UL << level_to_offset_bits(level);
+}
+
+static inline unsigned long level_size(int level)
+{
+	return 1UL << level_to_offset_bits(level);
+}
+
+static inline unsigned long align_to_level(unsigned long pfn, int level)
+{
+	return (pfn + level_size(level) - 1) & level_mask(level);
+}
 
 /* VT-d pages must always be _smaller_ than MM pages. Otherwise things
    are never going to work. */
···
 }
 
 
-static inline int width_to_agaw(int width);
-
 static int __iommu_calculate_agaw(struct intel_iommu *iommu, int max_gaw)
 {
 	unsigned long sagaw;
···
 	iommu->root_entry = NULL;
 out:
 	spin_unlock_irqrestore(&iommu->lock, flags);
-}
-
-/* page table handling */
-#define LEVEL_STRIDE		(9)
-#define LEVEL_MASK		(((u64)1 << LEVEL_STRIDE) - 1)
-
-static inline int agaw_to_level(int agaw)
-{
-	return agaw + 2;
-}
-
-static inline int agaw_to_width(int agaw)
-{
-	return 30 + agaw * LEVEL_STRIDE;
-
-}
-
-static inline int width_to_agaw(int width)
-{
-	return (width - 30) / LEVEL_STRIDE;
-}
-
-static inline unsigned int level_to_offset_bits(int level)
-{
-	return (level - 1) * LEVEL_STRIDE;
-}
-
-static inline int pfn_level_offset(unsigned long pfn, int level)
-{
-	return (pfn >> level_to_offset_bits(level)) & LEVEL_MASK;
-}
-
-static inline unsigned long level_mask(int level)
-{
-	return -1UL << level_to_offset_bits(level);
-}
-
-static inline unsigned long level_size(int level)
-{
-	return 1UL << level_to_offset_bits(level);
-}
-
-static inline unsigned long align_to_level(unsigned long pfn, int level)
-{
-	return (pfn + level_size(level) - 1) & level_mask(level);
 }
 
 static struct dma_pte *pfn_to_dma_pte(struct dmar_domain *domain,