powerpc/mm/hugetlb: Update huge_ptep_set_access_flags to call __ptep_set_access_flags directly

In a later patch, we want to update __ptep_set_access_flags take page size
arg. This makes ptep_set_access_flags only work with mmu_virtual_psize.
To simplify the code make huge_ptep_set_access_flags directly call
__ptep_set_access_flags so that we can compute the hugetlb page size in
hugetlb function.

Now that ptep_set_access_flags won't be called for hugetlb remove
the is_vm_hugetlb_page() check and add the assert of pte lock
unconditionally.
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

arch/powerpc/include/asm/hugetlb.h

@@ -166,22 +166,9 @@ static inline pte_t huge_pte_wrprotect(pte_t pte)
 	return pte_wrprotect(pte);
 }
 
-static inline int huge_ptep_set_access_flags(struct vm_area_struct *vma,
+extern int huge_ptep_set_access_flags(struct vm_area_struct *vma,
 				      unsigned long addr, pte_t *ptep,
-					     pte_t pte, int dirty)
-{
-#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
-	 * entry in the TLB miss handler asm will fault ad infinitum.
-	 */
-	ptep_set_access_flags(vma, addr, ptep, pte, dirty);
-	return 1;
-#else
-	return ptep_set_access_flags(vma, addr, ptep, pte, dirty);
-#endif
-}
+				      pte_t pte, int dirty);
 
 static inline pte_t huge_ptep_get(pte_t *ptep)
 {

arch/powerpc/mm/pgtable.c

@@ -221,7 +221,6 @@ int ptep_set_access_flags(struct vm_area_struct *vma, unsigned long address,
 	entry = set_access_flags_filter(entry, vma, dirty);
 	changed = !pte_same(*(ptep), entry);
 	if (changed) {
-		if (!is_vm_hugetlb_page(vma))
 		assert_pte_locked(vma->vm_mm, address);
 		__ptep_set_access_flags(vma->vm_mm, ptep, entry, address);
 		flush_tlb_page(vma, address);
@@ -229,6 +228,36 @@ int ptep_set_access_flags(struct vm_area_struct *vma, unsigned long address,
 	return changed;
 }
 
+#ifdef CONFIG_HUGETLB_PAGE
+extern int huge_ptep_set_access_flags(struct vm_area_struct *vma,
+				      unsigned long addr, pte_t *ptep,
+				      pte_t pte, int dirty)
+{
+#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
+	 * entry in the TLB miss handler asm will fault ad infinitum.
+	 */
+	ptep_set_access_flags(vma, addr, ptep, pte, dirty);
+	return 1;
+#else
+	int changed;
+
+	pte = set_access_flags_filter(pte, vma, dirty);
+	changed = !pte_same(*(ptep), pte);
+	if (changed) {
+#ifdef CONFIG_DEBUG_VM
+		assert_spin_locked(&vma->vm_mm->page_table_lock);
+#endif
+		__ptep_set_access_flags(vma->vm_mm, ptep, pte, addr);
+		flush_hugetlb_page(vma, addr);
+	}
+	return changed;
+#endif
+}
+#endif /* CONFIG_HUGETLB_PAGE */
+
 #ifdef CONFIG_DEBUG_VM
 void assert_pte_locked(struct mm_struct *mm, unsigned long addr)
 {