powerpc/mm: use generic version of pmdp_clear_flush()

Also move the pmd_trans_huge check to generic code.
Signed-off-by: NAneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Acked-by: NKirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

arch/powerpc/include/asm/pgtable-ppc64.h

@@ -573,10 +573,6 @@ extern int pmdp_clear_flush_young(struct vm_area_struct *vma,
 extern pmd_t pmdp_get_and_clear(struct mm_struct *mm,
 				unsigned long addr, pmd_t *pmdp);
 
-#define __HAVE_ARCH_PMDP_CLEAR_FLUSH
-extern pmd_t pmdp_clear_flush(struct vm_area_struct *vma, unsigned long address,
-			      pmd_t *pmdp);
-
 #define __HAVE_ARCH_PMDP_SET_WRPROTECT
 static inline void pmdp_set_wrprotect(struct mm_struct *mm, unsigned long addr,
 				      pmd_t *pmdp)

arch/powerpc/mm/pgtable_64.c

@@ -554,17 +554,6 @@ unsigned long pmd_hugepage_update(struct mm_struct *mm, unsigned long addr,
 	return old;
 }
 
-pmd_t pmdp_clear_flush(struct vm_area_struct *vma, unsigned long address,
-		       pmd_t *pmdp)
-{
-	pmd_t pmd;
-
-	VM_BUG_ON(address & ~HPAGE_PMD_MASK);
-	VM_BUG_ON(!pmd_trans_huge(*pmdp));
-	pmd = pmdp_get_and_clear(vma->vm_mm, address, pmdp);
-	return pmd;
-}
-
 pmd_t pmdp_collapse_flush(struct vm_area_struct *vma, unsigned long address,
 			  pmd_t *pmdp)
 {

arch/s390/include/asm/pgtable.h

@@ -1548,6 +1548,14 @@ static inline void pmdp_set_wrprotect(struct mm_struct *mm,
 	}
 }
 
+static inline pmd_t pmdp_collapse_flush(struct vm_area_struct *vma,
+					unsigned long address,
+					pmd_t *pmdp)
+{
+	return pmdp_get_and_clear(vma->vm_mm, address, pmdp);
+}
+#define pmdp_collapse_flush pmdp_collapse_flush
+
 #define pfn_pmd(pfn, pgprot)	mk_pmd_phys(__pa((pfn) << PAGE_SHIFT), (pgprot))
 #define mk_pmd(page, pgprot)	pfn_pmd(page_to_pfn(page), (pgprot))
 

include/asm-generic/pgtable.h

@@ -191,13 +191,8 @@ extern void pmdp_splitting_flush(struct vm_area_struct *vma,
 
 #ifndef pmdp_collapse_flush
 #ifdef CONFIG_TRANSPARENT_HUGEPAGE
-static inline pmd_t pmdp_collapse_flush(struct vm_area_struct *vma,
-					unsigned long address,
-					pmd_t *pmdp)
-{
-	return pmdp_clear_flush(vma, address, pmdp);
-}
-#define pmdp_collapse_flush pmdp_collapse_flush
+extern pmd_t pmdp_collapse_flush(struct vm_area_struct *vma,
+				 unsigned long address, pmd_t *pmdp);
 #else
 static inline pmd_t pmdp_collapse_flush(struct vm_area_struct *vma,
 					unsigned long address,

mm/pgtable-generic.c

@@ -126,6 +126,7 @@ pmd_t pmdp_clear_flush(struct vm_area_struct *vma, unsigned long address,
 {
 	pmd_t pmd;
 	VM_BUG_ON(address & ~HPAGE_PMD_MASK);
+	VM_BUG_ON(!pmd_trans_huge(*pmdp));
 	pmd = pmdp_get_and_clear(vma->vm_mm, address, pmdp);
 	flush_tlb_range(vma, address, address + HPAGE_PMD_SIZE);
 	return pmd;
@@ -198,3 +199,19 @@ void pmdp_invalidate(struct vm_area_struct *vma, unsigned long address,
 }
 #endif /* CONFIG_TRANSPARENT_HUGEPAGE */
 #endif
+
+#ifndef pmdp_collapse_flush
+#ifdef CONFIG_TRANSPARENT_HUGEPAGE
+pmd_t pmdp_collapse_flush(struct vm_area_struct *vma, unsigned long address,
+			  pmd_t *pmdp)
+{
+	pmd_t pmd;
+
+	VM_BUG_ON(address & ~HPAGE_PMD_MASK);
+	VM_BUG_ON(pmd_trans_huge(*pmdp));
+	pmd = pmdp_get_and_clear(vma->vm_mm, address, pmdp);
+	flush_tlb_range(vma, address, address + HPAGE_PMD_SIZE);
+	return pmd;
+}
+#endif /* CONFIG_TRANSPARENT_HUGEPAGE */
+#endif