powerpc: Define/use HUGETLB_NEED_PRELOAD insead of complicated #if

Define HUGETLB_NEED_PRELOAD in mmu-book3e.h for CONFIG_PPC64 instead
of having a much more complicated #if block.  This is easier to read
and maintain.

Signed-off-by: Becky Bruce <beckyb@kernel.crashing.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>

arch/powerpc/include/asm/hugetlb.h

@@ -124,8 +124,7 @@ static inline int huge_ptep_set_access_flags(struct vm_area_struct *vma,
 					     unsigned long addr, pte_t *ptep,
 					     pte_t pte, int dirty)
 {
-#if defined(CONFIG_PPC_MMU_NOHASH) && \
-	!(defined(CONFIG_PPC_FSL_BOOK3E) && defined(CONFIG_PPC32))
+#ifdef HUGETLB_NEED_PRELOAD
 	/*
 	 * The "return 1" forces a call of update_mmu_cache, which will write a
 	 * TLB entry.  Without this, platforms that don't do a write of the TLB

arch/powerpc/include/asm/mmu-book3e.h

@@ -258,6 +258,13 @@ extern int mmu_vmemmap_psize;
 
 #ifdef CONFIG_PPC64
 extern unsigned long linear_map_top;
+
+/*
+ * 64-bit booke platforms don't load the tlb in the tlb miss handler code.
+ * HUGETLB_NEED_PRELOAD handles this - it causes huge_ptep_set_access_flags to
+ * return 1, indicating that the tlb requires preloading.
+ */
+#define HUGETLB_NEED_PRELOAD
 #endif
 
 #endif /* !__ASSEMBLY__ */