Merge branch 'akpm' (patches from Andrew)

Merge first patchbomb from Andrew Morton:

 - a few misc things

 - ocfs2 udpates

 - kernel/watchdog.c feature work (took ages to get right)

 - most of MM.  A few tricky bits are held up and probably won't make 4.2.

* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (91 commits)
  mm: kmemleak_alloc_percpu() should follow the gfp from per_alloc()
  mm, thp: respect MPOL_PREFERRED policy with non-local node
  tmpfs: truncate prealloc blocks past i_size
  mm/memory hotplug: print the last vmemmap region at the end of hot add memory
  mm/mmap.c: optimization of do_mmap_pgoff function
  mm: kmemleak: optimise kmemleak_lock acquiring during kmemleak_scan
  mm: kmemleak: avoid deadlock on the kmemleak object insertion error path
  mm: kmemleak: do not acquire scan_mutex in kmemleak_do_cleanup()
  mm: kmemleak: fix delete_object_*() race when called on the same memory block
  mm: kmemleak: allow safe memory scanning during kmemleak disabling
  memcg: convert mem_cgroup->under_oom from atomic_t to int
  memcg: remove unused mem_cgroup->oom_wakeups
  frontswap: allow multiple backends
  x86, mirror: x86 enabling - find mirrored memory ranges
  mm/memblock: allocate boot time data structures from mirrored memory
  mm/memblock: add extra "flags" to memblock to allow selection of memory based on attribute
  mm: do not ignore mapping_gfp_mask in page cache allocation paths
  mm/cma.c: fix typos in comments
  mm/oom_kill.c: print points as unsigned int
  mm/hugetlb: handle races in alloc_huge_page and hugetlb_reserve_pages
  ...

71 files changed, 642 insertions, 202 deletions

diff --git a/arch/alpha/include/asm/mm-arch-hooks.h b/arch/alpha/include/asm/mm-arch-hooks.h
new file mode 100644
index 000000000000..b07fd862fec3
--- /dev/null
+++ b/arch/alpha/include/asm/mm-arch-hooks.h
@@ -0,0 +1,15 @@
+/*
+ * Architecture specific mm hooks
+ *
+ * Copyright (C) 2015, IBM Corporation
+ * Author: Laurent Dufour <ldufour@linux.vnet.ibm.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#ifndef _ASM_ALPHA_MM_ARCH_HOOKS_H
+#define _ASM_ALPHA_MM_ARCH_HOOKS_H
+
+#endif /* _ASM_ALPHA_MM_ARCH_HOOKS_H */
diff --git a/arch/arc/include/asm/mm-arch-hooks.h b/arch/arc/include/asm/mm-arch-hooks.h
new file mode 100644
index 000000000000..c37541c5f8ba
--- /dev/null
+++ b/arch/arc/include/asm/mm-arch-hooks.h
@@ -0,0 +1,15 @@
+/*
+ * Architecture specific mm hooks
+ *
+ * Copyright (C) 2015, IBM Corporation
+ * Author: Laurent Dufour <ldufour@linux.vnet.ibm.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#ifndef _ASM_ARC_MM_ARCH_HOOKS_H
+#define _ASM_ARC_MM_ARCH_HOOKS_H
+
+#endif /* _ASM_ARC_MM_ARCH_HOOKS_H */
diff --git a/arch/arm/include/asm/hugetlb.h b/arch/arm/include/asm/hugetlb.h
index 1f1b1cd112f3..31bb7dccb971 100644
--- a/arch/arm/include/asm/hugetlb.h
+++ b/arch/arm/include/asm/hugetlb.h
@@ -53,10 +53,6 @@ static inline int prepare_hugepage_range(struct file *file,
 	return 0;
 }
 
-static inline void hugetlb_prefault_arch_hook(struct mm_struct *mm)
-{
-}
-
 static inline int huge_pte_none(pte_t pte)
 {
 	return pte_none(pte);
diff --git a/arch/arm/include/asm/mm-arch-hooks.h b/arch/arm/include/asm/mm-arch-hooks.h
new file mode 100644
index 000000000000..7056660c7cc4
--- /dev/null
+++ b/arch/arm/include/asm/mm-arch-hooks.h
@@ -0,0 +1,15 @@
+/*
+ * Architecture specific mm hooks
+ *
+ * Copyright (C) 2015, IBM Corporation
+ * Author: Laurent Dufour <ldufour@linux.vnet.ibm.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#ifndef _ASM_ARM_MM_ARCH_HOOKS_H
+#define _ASM_ARM_MM_ARCH_HOOKS_H
+
+#endif /* _ASM_ARM_MM_ARCH_HOOKS_H */
diff --git a/arch/arm/mm/hugetlbpage.c b/arch/arm/mm/hugetlbpage.c
index c72412415093..fcafb521f14e 100644
--- a/arch/arm/mm/hugetlbpage.c
+++ b/arch/arm/mm/hugetlbpage.c
@@ -41,11 +41,6 @@ int pud_huge(pud_t pud)
 	return 0;
 }
 
-int huge_pmd_unshare(struct mm_struct *mm, unsigned long *addr, pte_t *ptep)
-{
-	return 0;
-}
-
 int pmd_huge(pmd_t pmd)
 {
 	return pmd_val(pmd) && !(pmd_val(pmd) & PMD_TABLE_BIT);
diff --git a/arch/arm64/include/asm/hugetlb.h b/arch/arm64/include/asm/hugetlb.h
index 5b7ca8ace95f..734c17e89e94 100644
--- a/arch/arm64/include/asm/hugetlb.h
+++ b/arch/arm64/include/asm/hugetlb.h
@@ -86,10 +86,6 @@ static inline int prepare_hugepage_range(struct file *file,
 	return 0;
 }
 
-static inline void hugetlb_prefault_arch_hook(struct mm_struct *mm)
-{
-}
-
 static inline int huge_pte_none(pte_t pte)
 {
 	return pte_none(pte);
diff --git a/arch/arm64/include/asm/mm-arch-hooks.h b/arch/arm64/include/asm/mm-arch-hooks.h
new file mode 100644
index 000000000000..562b655f5ba9
--- /dev/null
+++ b/arch/arm64/include/asm/mm-arch-hooks.h
@@ -0,0 +1,15 @@
+/*
+ * Architecture specific mm hooks
+ *
+ * Copyright (C) 2015, IBM Corporation
+ * Author: Laurent Dufour <ldufour@linux.vnet.ibm.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#ifndef _ASM_ARM64_MM_ARCH_HOOKS_H
+#define _ASM_ARM64_MM_ARCH_HOOKS_H
+
+#endif /* _ASM_ARM64_MM_ARCH_HOOKS_H */
diff --git a/arch/arm64/mm/hugetlbpage.c b/arch/arm64/mm/hugetlbpage.c
index 2de9d2e59d96..cccc4af87a03 100644
--- a/arch/arm64/mm/hugetlbpage.c
+++ b/arch/arm64/mm/hugetlbpage.c
@@ -31,13 +31,6 @@
 #include <asm/tlbflush.h>
 #include <asm/pgalloc.h>
 
-#ifndef CONFIG_ARCH_WANT_HUGE_PMD_SHARE
-int huge_pmd_unshare(struct mm_struct *mm, unsigned long *addr, pte_t *ptep)
-{
-	return 0;
-}
-#endif
-
 int pmd_huge(pmd_t pmd)
 {
 	return !(pmd_val(pmd) & PMD_TABLE_BIT);
diff --git a/arch/avr32/include/asm/mm-arch-hooks.h b/arch/avr32/include/asm/mm-arch-hooks.h
new file mode 100644
index 000000000000..145452ffbdad
--- /dev/null
+++ b/arch/avr32/include/asm/mm-arch-hooks.h
@@ -0,0 +1,15 @@
+/*
+ * Architecture specific mm hooks
+ *
+ * Copyright (C) 2015, IBM Corporation
+ * Author: Laurent Dufour <ldufour@linux.vnet.ibm.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#ifndef _ASM_AVR32_MM_ARCH_HOOKS_H
+#define _ASM_AVR32_MM_ARCH_HOOKS_H
+
+#endif /* _ASM_AVR32_MM_ARCH_HOOKS_H */
diff --git a/arch/blackfin/include/asm/mm-arch-hooks.h b/arch/blackfin/include/asm/mm-arch-hooks.h
new file mode 100644
index 000000000000..1c5211ec338f
--- /dev/null
+++ b/arch/blackfin/include/asm/mm-arch-hooks.h
@@ -0,0 +1,15 @@
+/*
+ * Architecture specific mm hooks
+ *
+ * Copyright (C) 2015, IBM Corporation
+ * Author: Laurent Dufour <ldufour@linux.vnet.ibm.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#ifndef _ASM_BLACKFIN_MM_ARCH_HOOKS_H
+#define _ASM_BLACKFIN_MM_ARCH_HOOKS_H
+
+#endif /* _ASM_BLACKFIN_MM_ARCH_HOOKS_H */
diff --git a/arch/c6x/include/asm/mm-arch-hooks.h b/arch/c6x/include/asm/mm-arch-hooks.h
new file mode 100644
index 000000000000..bb3c4a6ce8e9
--- /dev/null
+++ b/arch/c6x/include/asm/mm-arch-hooks.h
@@ -0,0 +1,15 @@
+/*
+ * Architecture specific mm hooks
+ *
+ * Copyright (C) 2015, IBM Corporation
+ * Author: Laurent Dufour <ldufour@linux.vnet.ibm.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#ifndef _ASM_C6X_MM_ARCH_HOOKS_H
+#define _ASM_C6X_MM_ARCH_HOOKS_H
+
+#endif /* _ASM_C6X_MM_ARCH_HOOKS_H */
diff --git a/arch/cris/include/asm/mm-arch-hooks.h b/arch/cris/include/asm/mm-arch-hooks.h
new file mode 100644
index 000000000000..314f774db2b0
--- /dev/null
+++ b/arch/cris/include/asm/mm-arch-hooks.h
@@ -0,0 +1,15 @@
+/*
+ * Architecture specific mm hooks
+ *
+ * Copyright (C) 2015, IBM Corporation
+ * Author: Laurent Dufour <ldufour@linux.vnet.ibm.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#ifndef _ASM_CRIS_MM_ARCH_HOOKS_H
+#define _ASM_CRIS_MM_ARCH_HOOKS_H
+
+#endif /* _ASM_CRIS_MM_ARCH_HOOKS_H */
diff --git a/arch/frv/include/asm/mm-arch-hooks.h b/arch/frv/include/asm/mm-arch-hooks.h
new file mode 100644
index 000000000000..51d13a870404
--- /dev/null
+++ b/arch/frv/include/asm/mm-arch-hooks.h
@@ -0,0 +1,15 @@
+/*
+ * Architecture specific mm hooks
+ *
+ * Copyright (C) 2015, IBM Corporation
+ * Author: Laurent Dufour <ldufour@linux.vnet.ibm.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#ifndef _ASM_FRV_MM_ARCH_HOOKS_H
+#define _ASM_FRV_MM_ARCH_HOOKS_H
+
+#endif /* _ASM_FRV_MM_ARCH_HOOKS_H */
diff --git a/arch/hexagon/include/asm/mm-arch-hooks.h b/arch/hexagon/include/asm/mm-arch-hooks.h
new file mode 100644
index 000000000000..05e8b939e416
--- /dev/null
+++ b/arch/hexagon/include/asm/mm-arch-hooks.h
@@ -0,0 +1,15 @@
+/*
+ * Architecture specific mm hooks
+ *
+ * Copyright (C) 2015, IBM Corporation
+ * Author: Laurent Dufour <ldufour@linux.vnet.ibm.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#ifndef _ASM_HEXAGON_MM_ARCH_HOOKS_H
+#define _ASM_HEXAGON_MM_ARCH_HOOKS_H
+
+#endif /* _ASM_HEXAGON_MM_ARCH_HOOKS_H */
diff --git a/arch/ia64/include/asm/hugetlb.h b/arch/ia64/include/asm/hugetlb.h
index aa910054b8e7..ff1377bc02a6 100644
--- a/arch/ia64/include/asm/hugetlb.h
+++ b/arch/ia64/include/asm/hugetlb.h
@@ -20,10 +20,6 @@ static inline int is_hugepage_only_range(struct mm_struct *mm,
 		REGION_NUMBER((addr)+(len)-1) == RGN_HPAGE);
 }
 
-static inline void hugetlb_prefault_arch_hook(struct mm_struct *mm)
-{
-}
-
 static inline void set_huge_pte_at(struct mm_struct *mm, unsigned long addr,
 				   pte_t *ptep, pte_t pte)
 {
diff --git a/arch/ia64/include/asm/mm-arch-hooks.h b/arch/ia64/include/asm/mm-arch-hooks.h
new file mode 100644
index 000000000000..ab4b5c698322
--- /dev/null
+++ b/arch/ia64/include/asm/mm-arch-hooks.h
@@ -0,0 +1,15 @@
+/*
+ * Architecture specific mm hooks
+ *
+ * Copyright (C) 2015, IBM Corporation
+ * Author: Laurent Dufour <ldufour@linux.vnet.ibm.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#ifndef _ASM_IA64_MM_ARCH_HOOKS_H
+#define _ASM_IA64_MM_ARCH_HOOKS_H
+
+#endif /* _ASM_IA64_MM_ARCH_HOOKS_H */
diff --git a/arch/ia64/mm/hugetlbpage.c b/arch/ia64/mm/hugetlbpage.c
index 52b7604b5215..f50d4b3f501a 100644
--- a/arch/ia64/mm/hugetlbpage.c
+++ b/arch/ia64/mm/hugetlbpage.c
@@ -65,11 +65,6 @@ huge_pte_offset (struct mm_struct *mm, unsigned long addr)
 	return pte;
 }
 
-int huge_pmd_unshare(struct mm_struct *mm, unsigned long *addr, pte_t *ptep)
-{
-	return 0;
-}
-
 #define mk_pte_huge(entry) { pte_val(entry) |= _PAGE_P; }
 
 /*
diff --git a/arch/m32r/include/asm/mm-arch-hooks.h b/arch/m32r/include/asm/mm-arch-hooks.h
new file mode 100644
index 000000000000..6d60b4750f41
--- /dev/null
+++ b/arch/m32r/include/asm/mm-arch-hooks.h
@@ -0,0 +1,15 @@
+/*
+ * Architecture specific mm hooks
+ *
+ * Copyright (C) 2015, IBM Corporation
+ * Author: Laurent Dufour <ldufour@linux.vnet.ibm.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#ifndef _ASM_M32R_MM_ARCH_HOOKS_H
+#define _ASM_M32R_MM_ARCH_HOOKS_H
+
+#endif /* _ASM_M32R_MM_ARCH_HOOKS_H */
diff --git a/arch/m68k/include/asm/mm-arch-hooks.h b/arch/m68k/include/asm/mm-arch-hooks.h
new file mode 100644
index 000000000000..7e8709bc90ae
--- /dev/null
+++ b/arch/m68k/include/asm/mm-arch-hooks.h
@@ -0,0 +1,15 @@
+/*
+ * Architecture specific mm hooks
+ *
+ * Copyright (C) 2015, IBM Corporation
+ * Author: Laurent Dufour <ldufour@linux.vnet.ibm.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#ifndef _ASM_M68K_MM_ARCH_HOOKS_H
+#define _ASM_M68K_MM_ARCH_HOOKS_H
+
+#endif /* _ASM_M68K_MM_ARCH_HOOKS_H */
diff --git a/arch/metag/include/asm/dma-mapping.h b/arch/metag/include/asm/dma-mapping.h
index 14b23efd9b7a..eb5cdec94be0 100644
--- a/arch/metag/include/asm/dma-mapping.h
+++ b/arch/metag/include/asm/dma-mapping.h
@@ -134,20 +134,24 @@ dma_sync_single_range_for_device(struct device *dev, dma_addr_t dma_handle,
 }
 
 static inline void
-dma_sync_sg_for_cpu(struct device *dev, struct scatterlist *sg, int nelems,
+dma_sync_sg_for_cpu(struct device *dev, struct scatterlist *sglist, int nelems,
 		    enum dma_data_direction direction)
 {
 	int i;
-	for (i = 0; i < nelems; i++, sg++)
+	struct scatterlist *sg;
+
+	for_each_sg(sglist, sg, nelems, i)
 		dma_sync_for_cpu(sg_virt(sg), sg->length, direction);
 }
 
 static inline void
-dma_sync_sg_for_device(struct device *dev, struct scatterlist *sg, int nelems,
-		       enum dma_data_direction direction)
+dma_sync_sg_for_device(struct device *dev, struct scatterlist *sglist,
+		       int nelems, enum dma_data_direction direction)
 {
 	int i;
-	for (i = 0; i < nelems; i++, sg++)
+	struct scatterlist *sg;
+
+	for_each_sg(sglist, sg, nelems, i)
 		dma_sync_for_device(sg_virt(sg), sg->length, direction);
 }
 
diff --git a/arch/metag/include/asm/hugetlb.h b/arch/metag/include/asm/hugetlb.h
index 471f481e67f3..f730b396d79b 100644
--- a/arch/metag/include/asm/hugetlb.h
+++ b/arch/metag/include/asm/hugetlb.h
@@ -14,10 +14,6 @@ static inline int is_hugepage_only_range(struct mm_struct *mm,
 int prepare_hugepage_range(struct file *file, unsigned long addr,
 						unsigned long len);
 
-static inline void hugetlb_prefault_arch_hook(struct mm_struct *mm)
-{
-}
-
 static inline void hugetlb_free_pgd_range(struct mmu_gather *tlb,
 					  unsigned long addr, unsigned long end,
 					  unsigned long floor,
diff --git a/arch/metag/include/asm/mm-arch-hooks.h b/arch/metag/include/asm/mm-arch-hooks.h
new file mode 100644
index 000000000000..b0072b2eb0de
--- /dev/null
+++ b/arch/metag/include/asm/mm-arch-hooks.h
@@ -0,0 +1,15 @@
+/*
+ * Architecture specific mm hooks
+ *
+ * Copyright (C) 2015, IBM Corporation
+ * Author: Laurent Dufour <ldufour@linux.vnet.ibm.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#ifndef _ASM_METAG_MM_ARCH_HOOKS_H
+#define _ASM_METAG_MM_ARCH_HOOKS_H
+
+#endif /* _ASM_METAG_MM_ARCH_HOOKS_H */
diff --git a/arch/metag/mm/hugetlbpage.c b/arch/metag/mm/hugetlbpage.c
index 7ca80ac42ed5..53f0f6c47027 100644
--- a/arch/metag/mm/hugetlbpage.c
+++ b/arch/metag/mm/hugetlbpage.c
@@ -89,11 +89,6 @@ pte_t *huge_pte_offset(struct mm_struct *mm, unsigned long addr)
 	return pte;
 }
 
-int huge_pmd_unshare(struct mm_struct *mm, unsigned long *addr, pte_t *ptep)
-{
-	return 0;
-}
-
 int pmd_huge(pmd_t pmd)
 {
 	return pmd_page_shift(pmd) > PAGE_SHIFT;
diff --git a/arch/microblaze/include/asm/mm-arch-hooks.h b/arch/microblaze/include/asm/mm-arch-hooks.h
new file mode 100644
index 000000000000..5c4065911bda
--- /dev/null
+++ b/arch/microblaze/include/asm/mm-arch-hooks.h
@@ -0,0 +1,15 @@
+/*
+ * Architecture specific mm hooks
+ *
+ * Copyright (C) 2015, IBM Corporation
+ * Author: Laurent Dufour <ldufour@linux.vnet.ibm.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#ifndef _ASM_MICROBLAZE_MM_ARCH_HOOKS_H
+#define _ASM_MICROBLAZE_MM_ARCH_HOOKS_H
+
+#endif /* _ASM_MICROBLAZE_MM_ARCH_HOOKS_H */
diff --git a/arch/mips/include/asm/hugetlb.h b/arch/mips/include/asm/hugetlb.h
index fe0d15d32660..4a5bb5453408 100644
--- a/arch/mips/include/asm/hugetlb.h
+++ b/arch/mips/include/asm/hugetlb.h
@@ -38,10 +38,6 @@ static inline int prepare_hugepage_range(struct file *file,
 	return 0;
 }
 
-static inline void hugetlb_prefault_arch_hook(struct mm_struct *mm)
-{
-}
-
 static inline void hugetlb_free_pgd_range(struct mmu_gather *tlb,
 					  unsigned long addr,
 					  unsigned long end,
diff --git a/arch/mips/include/asm/mm-arch-hooks.h b/arch/mips/include/asm/mm-arch-hooks.h
new file mode 100644
index 000000000000..b5609fe8e475
--- /dev/null
+++ b/arch/mips/include/asm/mm-arch-hooks.h
@@ -0,0 +1,15 @@
+/*
+ * Architecture specific mm hooks
+ *
+ * Copyright (C) 2015, IBM Corporation
+ * Author: Laurent Dufour <ldufour@linux.vnet.ibm.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#ifndef _ASM_MIPS_MM_ARCH_HOOKS_H
+#define _ASM_MIPS_MM_ARCH_HOOKS_H
+
+#endif /* _ASM_MIPS_MM_ARCH_HOOKS_H */
diff --git a/arch/mips/include/asm/pgtable.h b/arch/mips/include/asm/pgtable.h
index 819af9d057a8..9d8106758142 100644
--- a/arch/mips/include/asm/pgtable.h
+++ b/arch/mips/include/asm/pgtable.h
@@ -568,12 +568,12 @@ static inline pmd_t pmd_mknotpresent(pmd_t pmd)
 }
 
 /*
- * The generic version pmdp_get_and_clear uses a version of pmd_clear() with a
+ * The generic version pmdp_huge_get_and_clear uses a version of pmd_clear() with a
  * different prototype.
  */
-#define __HAVE_ARCH_PMDP_GET_AND_CLEAR
-static inline pmd_t pmdp_get_and_clear(struct mm_struct *mm,
-				       unsigned long address, pmd_t *pmdp)
+#define __HAVE_ARCH_PMDP_HUGE_GET_AND_CLEAR
+static inline pmd_t pmdp_huge_get_and_clear(struct mm_struct *mm,
+					    unsigned long address, pmd_t *pmdp)
 {
 	pmd_t old = *pmdp;
 
diff --git a/arch/mips/mm/hugetlbpage.c b/arch/mips/mm/hugetlbpage.c
index 06e0f421b41b..74aa6f62468f 100644
--- a/arch/mips/mm/hugetlbpage.c
+++ b/arch/mips/mm/hugetlbpage.c
@@ -51,11 +51,6 @@ pte_t *huge_pte_offset(struct mm_struct *mm, unsigned long addr)
 	return (pte_t *) pmd;
 }
 
-int huge_pmd_unshare(struct mm_struct *mm, unsigned long *addr, pte_t *ptep)
-{
-	return 0;
-}
-
 /*
  * This function checks for proper alignment of input addr and len parameters.
  */
diff --git a/arch/mn10300/include/asm/mm-arch-hooks.h b/arch/mn10300/include/asm/mm-arch-hooks.h
new file mode 100644
index 000000000000..e2029a652f4c
--- /dev/null
+++ b/arch/mn10300/include/asm/mm-arch-hooks.h
@@ -0,0 +1,15 @@
+/*
+ * Architecture specific mm hooks
+ *
+ * Copyright (C) 2015, IBM Corporation
+ * Author: Laurent Dufour <ldufour@linux.vnet.ibm.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#ifndef _ASM_MN10300_MM_ARCH_HOOKS_H
+#define _ASM_MN10300_MM_ARCH_HOOKS_H
+
+#endif /* _ASM_MN10300_MM_ARCH_HOOKS_H */
diff --git a/arch/nios2/include/asm/mm-arch-hooks.h b/arch/nios2/include/asm/mm-arch-hooks.h
new file mode 100644
index 000000000000..d7290dc68558
--- /dev/null
+++ b/arch/nios2/include/asm/mm-arch-hooks.h
@@ -0,0 +1,15 @@
+/*
+ * Architecture specific mm hooks
+ *
+ * Copyright (C) 2015, IBM Corporation
+ * Author: Laurent Dufour <ldufour@linux.vnet.ibm.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#ifndef _ASM_NIOS2_MM_ARCH_HOOKS_H
+#define _ASM_NIOS2_MM_ARCH_HOOKS_H
+
+#endif /* _ASM_NIOS2_MM_ARCH_HOOKS_H */
diff --git a/arch/openrisc/include/asm/mm-arch-hooks.h b/arch/openrisc/include/asm/mm-arch-hooks.h
new file mode 100644
index 000000000000..6d33cb555fe1
--- /dev/null
+++ b/arch/openrisc/include/asm/mm-arch-hooks.h
@@ -0,0 +1,15 @@
+/*
+ * Architecture specific mm hooks
+ *
+ * Copyright (C) 2015, IBM Corporation
+ * Author: Laurent Dufour <ldufour@linux.vnet.ibm.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#ifndef _ASM_OPENRISC_MM_ARCH_HOOKS_H
+#define _ASM_OPENRISC_MM_ARCH_HOOKS_H
+
+#endif /* _ASM_OPENRISC_MM_ARCH_HOOKS_H */
diff --git a/arch/parisc/include/asm/mm-arch-hooks.h b/arch/parisc/include/asm/mm-arch-hooks.h
new file mode 100644
index 000000000000..654ec63b0ee9
--- /dev/null
+++ b/arch/parisc/include/asm/mm-arch-hooks.h
@@ -0,0 +1,15 @@
+/*
+ * Architecture specific mm hooks
+ *
+ * Copyright (C) 2015, IBM Corporation
+ * Author: Laurent Dufour <ldufour@linux.vnet.ibm.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#ifndef _ASM_PARISC_MM_ARCH_HOOKS_H
+#define _ASM_PARISC_MM_ARCH_HOOKS_H
+
+#endif /* _ASM_PARISC_MM_ARCH_HOOKS_H */
diff --git a/arch/parisc/kernel/pci-dma.c b/arch/parisc/kernel/pci-dma.c
index ff834fd67478..b9402c9b3454 100644
--- a/arch/parisc/kernel/pci-dma.c
+++ b/arch/parisc/kernel/pci-dma.c
@@ -478,14 +478,16 @@ static void pa11_dma_unmap_single(struct device *dev, dma_addr_t dma_handle, siz
 static int pa11_dma_map_sg(struct device *dev, struct scatterlist *sglist, int nents, enum dma_data_direction direction)
 {
 	int i;
+	struct scatterlist *sg;
 
 	BUG_ON(direction == DMA_NONE);
 
-	for (i = 0; i < nents; i++, sglist++ ) {
-		unsigned long vaddr = (unsigned long)sg_virt(sglist);
-		sg_dma_address(sglist) = (dma_addr_t) virt_to_phys(vaddr);
-		sg_dma_len(sglist) = sglist->length;
-		flush_kernel_dcache_range(vaddr, sglist->length);
+	for_each_sg(sglist, sg, nents, i) {
+		unsigned long vaddr = (unsigned long)sg_virt(sg);
+
+		sg_dma_address(sg) = (dma_addr_t) virt_to_phys(vaddr);
+		sg_dma_len(sg) = sg->length;
+		flush_kernel_dcache_range(vaddr, sg->length);
 	}
 	return nents;
 }
@@ -493,6 +495,7 @@ static int pa11_dma_map_sg(struct device *dev, struct scatterlist *sglist, int n
 static void pa11_dma_unmap_sg(struct device *dev, struct scatterlist *sglist, int nents, enum dma_data_direction direction)
 {
 	int i;
+	struct scatterlist *sg;
 
 	BUG_ON(direction == DMA_NONE);
 
@@ -501,8 +504,8 @@ static void pa11_dma_unmap_sg(struct device *dev, struct scatterlist *sglist, in
 
 	/* once we do combining we'll need to use phys_to_virt(sg_dma_address(sglist)) */
 
-	for (i = 0; i < nents; i++, sglist++ )
-		flush_kernel_vmap_range(sg_virt(sglist), sglist->length);
+	for_each_sg(sglist, sg, nents, i)
+		flush_kernel_vmap_range(sg_virt(sg), sg->length);
 	return;
 }
 
@@ -523,21 +526,23 @@ static void pa11_dma_sync_single_for_device(struct device *dev, dma_addr_t dma_h
 static void pa11_dma_sync_sg_for_cpu(struct device *dev, struct scatterlist *sglist, int nents, enum dma_data_direction direction)
 {
 	int i;
+	struct scatterlist *sg;
 
 	/* once we do combining we'll need to use phys_to_virt(sg_dma_address(sglist)) */
 
-	for (i = 0; i < nents; i++, sglist++ )
-		flush_kernel_vmap_range(sg_virt(sglist), sglist->length);
+	for_each_sg(sglist, sg, nents, i)
+		flush_kernel_vmap_range(sg_virt(sg), sg->length);
 }
 
 static void pa11_dma_sync_sg_for_device(struct device *dev, struct scatterlist *sglist, int nents, enum dma_data_direction direction)
 {
 	int i;
+	struct scatterlist *sg;
 
 	/* once we do combining we'll need to use phys_to_virt(sg_dma_address(sglist)) */
 
-	for (i = 0; i < nents; i++, sglist++ )
-		flush_kernel_vmap_range(sg_virt(sglist), sglist->length);
+	for_each_sg(sglist, sg, nents, i)
+		flush_kernel_vmap_range(sg_virt(sg), sg->length);
 }
 
 struct hppa_dma_ops pcxl_dma_ops = {
diff --git a/arch/powerpc/include/asm/hugetlb.h b/arch/powerpc/include/asm/hugetlb.h
index 1d53a65b4ec1..4bbd3c8c2888 100644
--- a/arch/powerpc/include/asm/hugetlb.h
+++ b/arch/powerpc/include/asm/hugetlb.h
@@ -112,11 +112,6 @@ static inline int prepare_hugepage_range(struct file *file,
 	return 0;
 }
 
-static inline void hugetlb_prefault_arch_hook(struct mm_struct *mm)
-{
-}
-
-
 static inline void set_huge_pte_at(struct mm_struct *mm, unsigned long addr,
 				   pte_t *ptep, pte_t pte)
 {
diff --git a/arch/powerpc/include/asm/mm-arch-hooks.h b/arch/powerpc/include/asm/mm-arch-hooks.h
new file mode 100644
index 000000000000..f2a2da895897
--- /dev/null
+++ b/arch/powerpc/include/asm/mm-arch-hooks.h
@@ -0,0 +1,28 @@
+/*
+ * Architecture specific mm hooks
+ *
+ * Copyright (C) 2015, IBM Corporation
+ * Author: Laurent Dufour <ldufour@linux.vnet.ibm.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#ifndef _ASM_POWERPC_MM_ARCH_HOOKS_H
+#define _ASM_POWERPC_MM_ARCH_HOOKS_H
+
+static inline void arch_remap(struct mm_struct *mm,
+			      unsigned long old_start, unsigned long old_end,
+			      unsigned long new_start, unsigned long new_end)
+{
+	/*
+	 * mremap() doesn't allow moving multiple vmas so we can limit the
+	 * check to old_start == vdso_base.
+	 */
+	if (old_start == mm->context.vdso_base)
+		mm->context.vdso_base = new_start;
+}
+#define arch_remap arch_remap
+
+#endif /* _ASM_POWERPC_MM_ARCH_HOOKS_H */
diff --git a/arch/powerpc/include/asm/mmu_context.h b/arch/powerpc/include/asm/mmu_context.h
index 3e5184210d9b..878c27771717 100644
--- a/arch/powerpc/include/asm/mmu_context.h
+++ b/arch/powerpc/include/asm/mmu_context.h
@@ -8,7 +8,6 @@
 #include <linux/spinlock.h>
 #include <asm/mmu.h>	
 #include <asm/cputable.h>
-#include <asm-generic/mm_hooks.h>
 #include <asm/cputhreads.h>
 
 /*
@@ -127,5 +126,27 @@ static inline void enter_lazy_tlb(struct mm_struct *mm,
 #endif
 }
 
+static inline void arch_dup_mmap(struct mm_struct *oldmm,
+				 struct mm_struct *mm)
+{
+}
+
+static inline void arch_exit_mmap(struct mm_struct *mm)
+{
+}
+
+static inline void arch_unmap(struct mm_struct *mm,
+			      struct vm_area_struct *vma,
+			      unsigned long start, unsigned long end)
+{
+	if (start <= mm->context.vdso_base && mm->context.vdso_base < end)
+		mm->context.vdso_base = 0;
+}
+
+static inline void arch_bprm_mm_init(struct mm_struct *mm,
+				     struct vm_area_struct *vma)
+{
+}
+
 #endif /* __KERNEL__ */
 #endif /* __ASM_POWERPC_MMU_CONTEXT_H */
diff --git a/arch/powerpc/include/asm/pgtable-ppc64.h b/arch/powerpc/include/asm/pgtable-ppc64.h
index f890f7ce1593..3bb7488bd24b 100644
--- a/arch/powerpc/include/asm/pgtable-ppc64.h
+++ b/arch/powerpc/include/asm/pgtable-ppc64.h
@@ -569,13 +569,9 @@ extern int pmdp_test_and_clear_young(struct vm_area_struct *vma,
 extern int pmdp_clear_flush_young(struct vm_area_struct *vma,
 				  unsigned long address, pmd_t *pmdp);
 
-#define __HAVE_ARCH_PMDP_GET_AND_CLEAR
-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_HUGE_GET_AND_CLEAR
+extern pmd_t pmdp_huge_get_and_clear(struct mm_struct *mm,
+				     unsigned long addr, pmd_t *pmdp);
 
 #define __HAVE_ARCH_PMDP_SET_WRPROTECT
 static inline void pmdp_set_wrprotect(struct mm_struct *mm, unsigned long addr,
@@ -592,6 +588,10 @@ static inline void pmdp_set_wrprotect(struct mm_struct *mm, unsigned long addr,
 extern void pmdp_splitting_flush(struct vm_area_struct *vma,
 				 unsigned long address, pmd_t *pmdp);
 
+extern pmd_t pmdp_collapse_flush(struct vm_area_struct *vma,
+				 unsigned long address, pmd_t *pmdp);
+#define pmdp_collapse_flush pmdp_collapse_flush
+
 #define __HAVE_ARCH_PGTABLE_DEPOSIT
 extern void pgtable_trans_huge_deposit(struct mm_struct *mm, pmd_t *pmdp,
 				       pgtable_t pgtable);
diff --git a/arch/powerpc/kernel/vio.c b/arch/powerpc/kernel/vio.c
index b41426c60ef6..5f8dcdaa2820 100644
--- a/arch/powerpc/kernel/vio.c
+++ b/arch/powerpc/kernel/vio.c
@@ -557,11 +557,11 @@ static int vio_dma_iommu_map_sg(struct device *dev, struct scatterlist *sglist,
 	struct vio_dev *viodev = to_vio_dev(dev);
 	struct iommu_table *tbl;
 	struct scatterlist *sgl;
-	int ret, count = 0;
+	int ret, count;
 	size_t alloc_size = 0;
 
 	tbl = get_iommu_table_base(dev);
-	for (sgl = sglist; count < nelems; count++, sgl++)
+	for_each_sg(sglist, sgl, nelems, count)
 		alloc_size += roundup(sgl->length, IOMMU_PAGE_SIZE(tbl));
 
 	if (vio_cmo_alloc(viodev, alloc_size)) {
@@ -577,7 +577,7 @@ static int vio_dma_iommu_map_sg(struct device *dev, struct scatterlist *sglist,
 		return ret;
 	}
 
-	for (sgl = sglist, count = 0; count < ret; count++, sgl++)
+	for_each_sg(sglist, sgl, ret, count)
 		alloc_size -= roundup(sgl->dma_length, IOMMU_PAGE_SIZE(tbl));
 	if (alloc_size)
 		vio_cmo_dealloc(viodev, alloc_size);
@@ -594,10 +594,10 @@ static void vio_dma_iommu_unmap_sg(struct device *dev,
 	struct iommu_table *tbl;
 	struct scatterlist *sgl;
 	size_t alloc_size = 0;
-	int count = 0;
+	int count;
 
 	tbl = get_iommu_table_base(dev);
-	for (sgl = sglist; count < nelems; count++, sgl++)
+	for_each_sg(sglist, sgl, nelems, count)
 		alloc_size += roundup(sgl->dma_length, IOMMU_PAGE_SIZE(tbl));
 
 	dma_iommu_ops.unmap_sg(dev, sglist, nelems, direction, attrs);
diff --git a/arch/powerpc/mm/hugetlbpage.c b/arch/powerpc/mm/hugetlbpage.c
index 3385e3d0506e..38bd5d998c81 100644
--- a/arch/powerpc/mm/hugetlbpage.c
+++ b/arch/powerpc/mm/hugetlbpage.c
@@ -439,11 +439,6 @@ int alloc_bootmem_huge_page(struct hstate *hstate)
 }
 #endif
 
-int huge_pmd_unshare(struct mm_struct *mm, unsigned long *addr, pte_t *ptep)
-{
-	return 0;
-}
-
 #ifdef CONFIG_PPC_FSL_BOOK3E
 #define HUGEPD_FREELIST_SIZE \
 	((PAGE_SIZE - sizeof(struct hugepd_freelist)) / sizeof(pte_t))
diff --git a/arch/powerpc/mm/pgtable_64.c b/arch/powerpc/mm/pgtable_64.c
index 6bfadf1aa5cb..876232d64126 100644
--- a/arch/powerpc/mm/pgtable_64.c
+++ b/arch/powerpc/mm/pgtable_64.c
@@ -554,47 +554,42 @@ 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 pmdp_collapse_flush(struct vm_area_struct *vma, unsigned long address,
+			  pmd_t *pmdp)
 {
 	pmd_t pmd;
 
 	VM_BUG_ON(address & ~HPAGE_PMD_MASK);
-	if (pmd_trans_huge(*pmdp)) {
-		pmd = pmdp_get_and_clear(vma->vm_mm, address, pmdp);
-	} else {
-		/*
-		 * khugepaged calls this for normal pmd
-		 */
-		pmd = *pmdp;
-		pmd_clear(pmdp);
-		/*
-		 * Wait for all pending hash_page to finish. This is needed
-		 * in case of subpage collapse. When we collapse normal pages
-		 * to hugepage, we first clear the pmd, then invalidate all
-		 * the PTE entries. The assumption here is that any low level
-		 * page fault will see a none pmd and take the slow path that
-		 * will wait on mmap_sem. But we could very well be in a
-		 * hash_page with local ptep pointer value. Such a hash page
-		 * can result in adding new HPTE entries for normal subpages.
-		 * That means we could be modifying the page content as we
-		 * copy them to a huge page. So wait for parallel hash_page
-		 * to finish before invalidating HPTE entries. We can do this
-		 * by sending an IPI to all the cpus and executing a dummy
-		 * function there.
-		 */
-		kick_all_cpus_sync();
-		/*
-		 * Now invalidate the hpte entries in the range
-		 * covered by pmd. This make sure we take a
-		 * fault and will find the pmd as none, which will
-		 * result in a major fault which takes mmap_sem and
-		 * hence wait for collapse to complete. Without this
-		 * the __collapse_huge_page_copy can result in copying
-		 * the old content.
-		 */
-		flush_tlb_pmd_range(vma->vm_mm, &pmd, address);
-	}
+	VM_BUG_ON(pmd_trans_huge(*pmdp));
+
+	pmd = *pmdp;
+	pmd_clear(pmdp);
+	/*
+	 * Wait for all pending hash_page to finish. This is needed
+	 * in case of subpage collapse. When we collapse normal pages
+	 * to hugepage, we first clear the pmd, then invalidate all
+	 * the PTE entries. The assumption here is that any low level
+	 * page fault will see a none pmd and take the slow path that
+	 * will wait on mmap_sem. But we could very well be in a
+	 * hash_page with local ptep pointer value. Such a hash page
+	 * can result in adding new HPTE entries for normal subpages.
+	 * That means we could be modifying the page content as we
+	 * copy them to a huge page. So wait for parallel hash_page
+	 * to finish before invalidating HPTE entries. We can do this
+	 * by sending an IPI to all the cpus and executing a dummy
+	 * function there.
+	 */
+	kick_all_cpus_sync();
+	/*
+	 * Now invalidate the hpte entries in the range
+	 * covered by pmd. This make sure we take a
+	 * fault and will find the pmd as none, which will
+	 * result in a major fault which takes mmap_sem and
+	 * hence wait for collapse to complete. Without this
+	 * the __collapse_huge_page_copy can result in copying
+	 * the old content.
+	 */
+	flush_tlb_pmd_range(vma->vm_mm, &pmd, address);
 	return pmd;
 }
 
@@ -817,8 +812,8 @@ void update_mmu_cache_pmd(struct vm_area_struct *vma, unsigned long addr,
 	return;
 }
 
-pmd_t pmdp_get_and_clear(struct mm_struct *mm,
-			 unsigned long addr, pmd_t *pmdp)
+pmd_t pmdp_huge_get_and_clear(struct mm_struct *mm,
+			      unsigned long addr, pmd_t *pmdp)
 {
 	pmd_t old_pmd;
 	pgtable_t pgtable;
diff --git a/arch/s390/include/asm/hugetlb.h b/arch/s390/include/asm/hugetlb.h
index 11eae5f55b70..dfb542ade6b1 100644
--- a/arch/s390/include/asm/hugetlb.h
+++ b/arch/s390/include/asm/hugetlb.h
@@ -35,7 +35,6 @@ static inline int prepare_hugepage_range(struct file *file,
 	return 0;
 }
 
-#define hugetlb_prefault_arch_hook(mm)		do { } while (0)
 #define arch_clear_hugepage_flags(page)		do { } while (0)
 
 int arch_prepare_hugepage(struct page *page);
diff --git a/arch/s390/include/asm/mm-arch-hooks.h b/arch/s390/include/asm/mm-arch-hooks.h
new file mode 100644
index 000000000000..07680b2f3c59
--- /dev/null
+++ b/arch/s390/include/asm/mm-arch-hooks.h
@@ -0,0 +1,15 @@
+/*
+ * Architecture specific mm hooks
+ *
+ * Copyright (C) 2015, IBM Corporation
+ * Author: Laurent Dufour <ldufour@linux.vnet.ibm.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#ifndef _ASM_S390_MM_ARCH_HOOKS_H
+#define _ASM_S390_MM_ARCH_HOOKS_H
+
+#endif /* _ASM_S390_MM_ARCH_HOOKS_H */
diff --git a/arch/s390/include/asm/pgtable.h b/arch/s390/include/asm/pgtable.h
index 0bb2da79adf3..f66d82798a6a 100644
--- a/arch/s390/include/asm/pgtable.h
+++ b/arch/s390/include/asm/pgtable.h
@@ -1498,9 +1498,9 @@ static inline int pmdp_test_and_clear_young(struct vm_area_struct *vma,
 	return pmd_young(pmd);
 }
 
-#define __HAVE_ARCH_PMDP_GET_AND_CLEAR
-static inline pmd_t pmdp_get_and_clear(struct mm_struct *mm,
-				       unsigned long address, pmd_t *pmdp)
+#define __HAVE_ARCH_PMDP_HUGE_GET_AND_CLEAR
+static inline pmd_t pmdp_huge_get_and_clear(struct mm_struct *mm,
+					    unsigned long address, pmd_t *pmdp)
 {
 	pmd_t pmd = *pmdp;
 
@@ -1509,10 +1509,10 @@ static inline pmd_t pmdp_get_and_clear(struct mm_struct *mm,
 	return pmd;
 }
 
-#define __HAVE_ARCH_PMDP_GET_AND_CLEAR_FULL
-static inline pmd_t pmdp_get_and_clear_full(struct mm_struct *mm,
-					    unsigned long address,
-					    pmd_t *pmdp, int full)
+#define __HAVE_ARCH_PMDP_HUGE_GET_AND_CLEAR_FULL
+static inline pmd_t pmdp_huge_get_and_clear_full(struct mm_struct *mm,
+						 unsigned long address,
+						 pmd_t *pmdp, int full)
 {
 	pmd_t pmd = *pmdp;
 
@@ -1522,11 +1522,11 @@ static inline pmd_t pmdp_get_and_clear_full(struct mm_struct *mm,
 	return pmd;
 }
 
-#define __HAVE_ARCH_PMDP_CLEAR_FLUSH
-static inline pmd_t pmdp_clear_flush(struct vm_area_struct *vma,
-				     unsigned long address, pmd_t *pmdp)
+#define __HAVE_ARCH_PMDP_HUGE_CLEAR_FLUSH
+static inline pmd_t pmdp_huge_clear_flush(struct vm_area_struct *vma,
+					  unsigned long address, pmd_t *pmdp)
 {
-	return pmdp_get_and_clear(vma->vm_mm, address, pmdp);
+	return pmdp_huge_get_and_clear(vma->vm_mm, address, pmdp);
 }
 
 #define __HAVE_ARCH_PMDP_INVALIDATE
@@ -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_huge_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))
 
diff --git a/arch/s390/kernel/crash_dump.c b/arch/s390/kernel/crash_dump.c
index d9f0dcfcae5e..7a75ad4594e3 100644
--- a/arch/s390/kernel/crash_dump.c
+++ b/arch/s390/kernel/crash_dump.c
@@ -33,11 +33,12 @@ static struct memblock_type oldmem_type = {
 };
 
 #define for_each_dump_mem_range(i, nid, p_start, p_end, p_nid)		\
-	for (i = 0, __next_mem_range(&i, nid, &memblock.physmem,	\
+	for (i = 0, __next_mem_range(&i, nid, MEMBLOCK_NONE,		\
+				     &memblock.physmem,			\
 				     &oldmem_type, p_start,		\
 				     p_end, p_nid);			\
 	     i != (u64)ULLONG_MAX;					\
-	     __next_mem_range(&i, nid, &memblock.physmem,		\
+	     __next_mem_range(&i, nid, MEMBLOCK_NONE, &memblock.physmem,\
 			      &oldmem_type,				\
 			      p_start, p_end, p_nid))
 
diff --git a/arch/s390/mm/hugetlbpage.c b/arch/s390/mm/hugetlbpage.c
index e617e74b7be2..c3f8e3df92ff 100644
--- a/arch/s390/mm/hugetlbpage.c
+++ b/arch/s390/mm/hugetlbpage.c
@@ -193,11 +193,6 @@ pte_t *huge_pte_offset(struct mm_struct *mm, unsigned long addr)
 	return (pte_t *) pmdp;
 }
 
-int huge_pmd_unshare(struct mm_struct *mm, unsigned long *addr, pte_t *ptep)
-{
-	return 0;
-}
-
 int pmd_huge(pmd_t pmd)
 {
 	if (!MACHINE_HAS_HPAGE)
diff --git a/arch/score/include/asm/mm-arch-hooks.h b/arch/score/include/asm/mm-arch-hooks.h
new file mode 100644
index 000000000000..5e38689f189a
--- /dev/null
+++ b/arch/score/include/asm/mm-arch-hooks.h
@@ -0,0 +1,15 @@
+/*
+ * Architecture specific mm hooks
+ *
+ * Copyright (C) 2015, IBM Corporation
+ * Author: Laurent Dufour <ldufour@linux.vnet.ibm.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#ifndef _ASM_SCORE_MM_ARCH_HOOKS_H
+#define _ASM_SCORE_MM_ARCH_HOOKS_H
+
+#endif /* _ASM_SCORE_MM_ARCH_HOOKS_H */
diff --git a/arch/sh/include/asm/hugetlb.h b/arch/sh/include/asm/hugetlb.h
index 699255d6d1c6..b788a9bc8918 100644
--- a/arch/sh/include/asm/hugetlb.h
+++ b/arch/sh/include/asm/hugetlb.h
@@ -26,9 +26,6 @@ static inline int prepare_hugepage_range(struct file *file,
 	return 0;
 }
 
-static inline void hugetlb_prefault_arch_hook(struct mm_struct *mm) {
-}
-
 static inline void hugetlb_free_pgd_range(struct mmu_gather *tlb,
 					  unsigned long addr, unsigned long end,
 					  unsigned long floor,
diff --git a/arch/sh/include/asm/mm-arch-hooks.h b/arch/sh/include/asm/mm-arch-hooks.h
new file mode 100644
index 000000000000..18087298b728
--- /dev/null
+++ b/arch/sh/include/asm/mm-arch-hooks.h
@@ -0,0 +1,15 @@
+/*
+ * Architecture specific mm hooks
+ *
+ * Copyright (C) 2015, IBM Corporation
+ * Author: Laurent Dufour <ldufour@linux.vnet.ibm.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#ifndef _ASM_SH_MM_ARCH_HOOKS_H
+#define _ASM_SH_MM_ARCH_HOOKS_H
+
+#endif /* _ASM_SH_MM_ARCH_HOOKS_H */
diff --git a/arch/sh/mm/hugetlbpage.c b/arch/sh/mm/hugetlbpage.c
index 534bc978af8a..6385f60209b6 100644
--- a/arch/sh/mm/hugetlbpage.c
+++ b/arch/sh/mm/hugetlbpage.c
@@ -62,11 +62,6 @@ pte_t *huge_pte_offset(struct mm_struct *mm, unsigned long addr)
 	return pte;
 }
 
-int huge_pmd_unshare(struct mm_struct *mm, unsigned long *addr, pte_t *ptep)
-{
-	return 0;
-}
-
 int pmd_huge(pmd_t pmd)
 {
 	return 0;
diff --git a/arch/sparc/include/asm/hugetlb.h b/arch/sparc/include/asm/hugetlb.h
index e4cab465b81f..3130d7636312 100644
--- a/arch/sparc/include/asm/hugetlb.h
+++ b/arch/sparc/include/asm/hugetlb.h
@@ -11,10 +11,6 @@ void set_huge_pte_at(struct mm_struct *mm, unsigned long addr,
 pte_t huge_ptep_get_and_clear(struct mm_struct *mm, unsigned long addr,
 			      pte_t *ptep);
 
-static inline void hugetlb_prefault_arch_hook(struct mm_struct *mm)
-{
-}
-
 static inline int is_hugepage_only_range(struct mm_struct *mm,
 					 unsigned long addr,
 					 unsigned long len) {
diff --git a/arch/sparc/include/asm/mm-arch-hooks.h b/arch/sparc/include/asm/mm-arch-hooks.h
new file mode 100644
index 000000000000..b89ba44c16f1
--- /dev/null
+++ b/arch/sparc/include/asm/mm-arch-hooks.h
@@ -0,0 +1,15 @@
+/*
+ * Architecture specific mm hooks
+ *
+ * Copyright (C) 2015, IBM Corporation
+ * Author: Laurent Dufour <ldufour@linux.vnet.ibm.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#ifndef _ASM_SPARC_MM_ARCH_HOOKS_H
+#define _ASM_SPARC_MM_ARCH_HOOKS_H
+
+#endif /* _ASM_SPARC_MM_ARCH_HOOKS_H */
diff --git a/arch/sparc/include/asm/pgtable_64.h b/arch/sparc/include/asm/pgtable_64.h
index 2a52c91d2c8a..131d36fcd07a 100644
--- a/arch/sparc/include/asm/pgtable_64.h
+++ b/arch/sparc/include/asm/pgtable_64.h
@@ -865,10 +865,10 @@ static inline unsigned long pud_pfn(pud_t pud)
 void tlb_batch_add(struct mm_struct *mm, unsigned long vaddr,
 		   pte_t *ptep, pte_t orig, int fullmm);
 
-#define __HAVE_ARCH_PMDP_GET_AND_CLEAR
-static inline pmd_t pmdp_get_and_clear(struct mm_struct *mm,
-				       unsigned long addr,
-				       pmd_t *pmdp)
+#define __HAVE_ARCH_PMDP_HUGE_GET_AND_CLEAR
+static inline pmd_t pmdp_huge_get_and_clear(struct mm_struct *mm,
+					    unsigned long addr,
+					    pmd_t *pmdp)
 {
 	pmd_t pmd = *pmdp;
 	set_pmd_at(mm, addr, pmdp, __pmd(0UL));
diff --git a/arch/sparc/kernel/ldc.c b/arch/sparc/kernel/ldc.c
index 7d3ca30fcd15..1ae5eb1bb045 100644
--- a/arch/sparc/kernel/ldc.c
+++ b/arch/sparc/kernel/ldc.c
@@ -2086,6 +2086,7 @@ int ldc_map_sg(struct ldc_channel *lp,
 	struct cookie_state state;
 	struct ldc_iommu *iommu;
 	int err;
+	struct scatterlist *s;
 
 	if (map_perm & ~LDC_MAP_ALL)
 		return -EINVAL;
@@ -2112,9 +2113,10 @@ int ldc_map_sg(struct ldc_channel *lp,
 	state.pte_idx = (base - iommu->page_table);
 	state.nc = 0;
 
-	for (i = 0; i < num_sg; i++)
-		fill_cookies(&state, page_to_pfn(sg_page(&sg[i])) << PAGE_SHIFT,
-			     sg[i].offset, sg[i].length);
+	for_each_sg(sg, s, num_sg, i) {
+		fill_cookies(&state, page_to_pfn(sg_page(s)) << PAGE_SHIFT,
+			     s->offset, s->length);
+	}
 
 	return state.nc;
 }
diff --git a/arch/sparc/mm/hugetlbpage.c b/arch/sparc/mm/hugetlbpage.c
index 4242eab12e10..131eaf4ad7f5 100644
--- a/arch/sparc/mm/hugetlbpage.c
+++ b/arch/sparc/mm/hugetlbpage.c
@@ -172,11 +172,6 @@ pte_t *huge_pte_offset(struct mm_struct *mm, unsigned long addr)
 	return pte;
 }
 
-int huge_pmd_unshare(struct mm_struct *mm, unsigned long *addr, pte_t *ptep)
-{
-	return 0;
-}
-
 void set_huge_pte_at(struct mm_struct *mm, unsigned long addr,
 		     pte_t *ptep, pte_t entry)
 {
diff --git a/arch/sparc/mm/init_64.c b/arch/sparc/mm/init_64.c
index c5d08b89a96c..4ac88b757514 100644
--- a/arch/sparc/mm/init_64.c
+++ b/arch/sparc/mm/init_64.c
@@ -1966,7 +1966,8 @@ static phys_addr_t __init available_memory(void)
 	phys_addr_t pa_start, pa_end;
 	u64 i;
 
-	for_each_free_mem_range(i, NUMA_NO_NODE, &pa_start, &pa_end, NULL)
+	for_each_free_mem_range(i, NUMA_NO_NODE, MEMBLOCK_NONE, &pa_start,
+				&pa_end, NULL)
 		available = available + (pa_end  - pa_start);
 
 	return available;
@@ -1992,7 +1993,8 @@ static void __init reduce_memory(phys_addr_t limit_ram)
 	if (limit_ram >= avail_ram)
 		return;
 
-	for_each_free_mem_range(i, NUMA_NO_NODE, &pa_start, &pa_end, NULL) {
+	for_each_free_mem_range(i, NUMA_NO_NODE, MEMBLOCK_NONE, &pa_start,
+				&pa_end, NULL) {
 		phys_addr_t region_size = pa_end - pa_start;
 		phys_addr_t clip_start = pa_start;
 
diff --git a/arch/tile/include/asm/hugetlb.h b/arch/tile/include/asm/hugetlb.h
index 3257733003f8..1abd00c55236 100644
--- a/arch/tile/include/asm/hugetlb.h
+++ b/arch/tile/include/asm/hugetlb.h
@@ -40,10 +40,6 @@ static inline int prepare_hugepage_range(struct file *file,
 	return 0;
 }
 
-static inline void hugetlb_prefault_arch_hook(struct mm_struct *mm)
-{
-}
-
 static inline void hugetlb_free_pgd_range(struct mmu_gather *tlb,
 					  unsigned long addr, unsigned long end,
 					  unsigned long floor,
diff --git a/arch/tile/include/asm/mm-arch-hooks.h b/arch/tile/include/asm/mm-arch-hooks.h
new file mode 100644
index 000000000000..d1709ea774f7
--- /dev/null
+++ b/arch/tile/include/asm/mm-arch-hooks.h
@@ -0,0 +1,15 @@
+/*
+ * Architecture specific mm hooks
+ *
+ * Copyright (C) 2015, IBM Corporation
+ * Author: Laurent Dufour <ldufour@linux.vnet.ibm.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#ifndef _ASM_TILE_MM_ARCH_HOOKS_H
+#define _ASM_TILE_MM_ARCH_HOOKS_H
+
+#endif /* _ASM_TILE_MM_ARCH_HOOKS_H */
diff --git a/arch/tile/include/asm/pgtable.h b/arch/tile/include/asm/pgtable.h
index 95a4f19d16c5..2b05ccbebed9 100644
--- a/arch/tile/include/asm/pgtable.h
+++ b/arch/tile/include/asm/pgtable.h
@@ -414,10 +414,10 @@ static inline void pmdp_set_wrprotect(struct mm_struct *mm,
 }
 
 
-#define __HAVE_ARCH_PMDP_GET_AND_CLEAR
-static inline pmd_t pmdp_get_and_clear(struct mm_struct *mm,
-				       unsigned long address,
-				       pmd_t *pmdp)
+#define __HAVE_ARCH_PMDP_HUGE_GET_AND_CLEAR
+static inline pmd_t pmdp_huge_get_and_clear(struct mm_struct *mm,
+					    unsigned long address,
+					    pmd_t *pmdp)
 {
 	return pte_pmd(ptep_get_and_clear(mm, address, pmdp_ptep(pmdp)));
 }
diff --git a/arch/tile/mm/hugetlbpage.c b/arch/tile/mm/hugetlbpage.c
index 8416240c322c..c034dc3fe2d4 100644
--- a/arch/tile/mm/hugetlbpage.c
+++ b/arch/tile/mm/hugetlbpage.c
@@ -160,11 +160,6 @@ int pud_huge(pud_t pud)
 	return !!(pud_val(pud) & _PAGE_HUGE_PAGE);
 }
 
-int huge_pmd_unshare(struct mm_struct *mm, unsigned long *addr, pte_t *ptep)
-{
-	return 0;
-}
-
 #ifdef HAVE_ARCH_HUGETLB_UNMAPPED_AREA
 static unsigned long hugetlb_get_unmapped_area_bottomup(struct file *file,
 		unsigned long addr, unsigned long len,
diff --git a/arch/um/include/asm/mm-arch-hooks.h b/arch/um/include/asm/mm-arch-hooks.h
new file mode 100644
index 000000000000..a7c8b0dfdd4e
--- /dev/null
+++ b/arch/um/include/asm/mm-arch-hooks.h
@@ -0,0 +1,15 @@
+/*
+ * Architecture specific mm hooks
+ *
+ * Copyright (C) 2015, IBM Corporation
+ * Author: Laurent Dufour <ldufour@linux.vnet.ibm.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#ifndef _ASM_UM_MM_ARCH_HOOKS_H
+#define _ASM_UM_MM_ARCH_HOOKS_H
+
+#endif /* _ASM_UM_MM_ARCH_HOOKS_H */
diff --git a/arch/unicore32/include/asm/mm-arch-hooks.h b/arch/unicore32/include/asm/mm-arch-hooks.h
new file mode 100644
index 000000000000..4d79a850c509
--- /dev/null
+++ b/arch/unicore32/include/asm/mm-arch-hooks.h
@@ -0,0 +1,15 @@
+/*
+ * Architecture specific mm hooks
+ *
+ * Copyright (C) 2015, IBM Corporation
+ * Author: Laurent Dufour <ldufour@linux.vnet.ibm.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#ifndef _ASM_UNICORE32_MM_ARCH_HOOKS_H
+#define _ASM_UNICORE32_MM_ARCH_HOOKS_H
+
+#endif /* _ASM_UNICORE32_MM_ARCH_HOOKS_H */
diff --git a/arch/x86/include/asm/hugetlb.h b/arch/x86/include/asm/hugetlb.h
index 68c05398bba9..dab7a3a750bf 100644
--- a/arch/x86/include/asm/hugetlb.h
+++ b/arch/x86/include/asm/hugetlb.h
@@ -26,9 +26,6 @@ static inline int prepare_hugepage_range(struct file *file,
 	return 0;
 }
 
-static inline void hugetlb_prefault_arch_hook(struct mm_struct *mm) {
-}
-
 static inline void hugetlb_free_pgd_range(struct mmu_gather *tlb,
 					  unsigned long addr, unsigned long end,
 					  unsigned long floor,
diff --git a/arch/x86/include/asm/mm-arch-hooks.h b/arch/x86/include/asm/mm-arch-hooks.h
new file mode 100644
index 000000000000..4e881a342236
--- /dev/null
+++ b/arch/x86/include/asm/mm-arch-hooks.h
@@ -0,0 +1,15 @@
+/*
+ * Architecture specific mm hooks
+ *
+ * Copyright (C) 2015, IBM Corporation
+ * Author: Laurent Dufour <ldufour@linux.vnet.ibm.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#ifndef _ASM_X86_MM_ARCH_HOOKS_H
+#define _ASM_X86_MM_ARCH_HOOKS_H
+
+#endif /* _ASM_X86_MM_ARCH_HOOKS_H */
diff --git a/arch/x86/include/asm/pgtable.h b/arch/x86/include/asm/pgtable.h
index 2562e303405b..867da5bbb4a3 100644
--- a/arch/x86/include/asm/pgtable.h
+++ b/arch/x86/include/asm/pgtable.h
@@ -805,8 +805,8 @@ static inline int pmd_write(pmd_t pmd)
 	return pmd_flags(pmd) & _PAGE_RW;
 }
 
-#define __HAVE_ARCH_PMDP_GET_AND_CLEAR
-static inline pmd_t pmdp_get_and_clear(struct mm_struct *mm, unsigned long addr,
+#define __HAVE_ARCH_PMDP_HUGE_GET_AND_CLEAR
+static inline pmd_t pmdp_huge_get_and_clear(struct mm_struct *mm, unsigned long addr,
 				       pmd_t *pmdp)
 {
 	pmd_t pmd = native_pmdp_get_and_clear(pmdp);
diff --git a/arch/x86/kernel/check.c b/arch/x86/kernel/check.c
index 83a7995625a6..58118e207a69 100644
--- a/arch/x86/kernel/check.c
+++ b/arch/x86/kernel/check.c
@@ -91,7 +91,8 @@ void __init setup_bios_corruption_check(void)
 
 	corruption_check_size = round_up(corruption_check_size, PAGE_SIZE);
 
-	for_each_free_mem_range(i, NUMA_NO_NODE, &start, &end, NULL) {
+	for_each_free_mem_range(i, NUMA_NO_NODE, MEMBLOCK_NONE, &start, &end,
+				NULL) {
 		start = clamp_t(phys_addr_t, round_up(start, PAGE_SIZE),
 				PAGE_SIZE, corruption_check_size);
 		end = clamp_t(phys_addr_t, round_down(end, PAGE_SIZE),
diff --git a/arch/x86/kernel/e820.c b/arch/x86/kernel/e820.c
index e2ce85db2283..c8dda42cb6a3 100644
--- a/arch/x86/kernel/e820.c
+++ b/arch/x86/kernel/e820.c
@@ -1123,7 +1123,8 @@ void __init memblock_find_dma_reserve(void)
 		nr_pages += end_pfn - start_pfn;
 	}
 
-	for_each_free_mem_range(u, NUMA_NO_NODE, &start, &end, NULL) {
+	for_each_free_mem_range(u, NUMA_NO_NODE, MEMBLOCK_NONE, &start, &end,
+				NULL) {
 		start_pfn = min_t(unsigned long, PFN_UP(start), MAX_DMA_PFN);
 		end_pfn = min_t(unsigned long, PFN_DOWN(end), MAX_DMA_PFN);
 		if (start_pfn < end_pfn)
diff --git a/arch/x86/kernel/setup.c b/arch/x86/kernel/setup.c
index 39ca113676fe..d3b95b89e9b2 100644
--- a/arch/x86/kernel/setup.c
+++ b/arch/x86/kernel/setup.c
@@ -1105,6 +1105,9 @@ void __init setup_arch(char **cmdline_p)
 	memblock_set_current_limit(ISA_END_ADDRESS);
 	memblock_x86_fill();
 
+	if (efi_enabled(EFI_BOOT))
+		efi_find_mirror();
+
 	/*
 	 * The EFI specification says that boot service code won't be called
 	 * after ExitBootServices(). This is, in fact, a lie.
diff --git a/arch/x86/mm/init_32.c b/arch/x86/mm/init_32.c
index c8140e12816a..8340e45c891a 100644
--- a/arch/x86/mm/init_32.c
+++ b/arch/x86/mm/init_32.c
@@ -433,7 +433,7 @@ void __init add_highpages_with_active_regions(int nid,
 	phys_addr_t start, end;
 	u64 i;
 
-	for_each_free_mem_range(i, nid, &start, &end, NULL) {
+	for_each_free_mem_range(i, nid, MEMBLOCK_NONE, &start, &end, NULL) {
 		unsigned long pfn = clamp_t(unsigned long, PFN_UP(start),
 					    start_pfn, end_pfn);
 		unsigned long e_pfn = clamp_t(unsigned long, PFN_DOWN(end),
diff --git a/arch/x86/platform/efi/efi.c b/arch/x86/platform/efi/efi.c
index 3b984c3aa1b0..c1c382c58c60 100644
--- a/arch/x86/platform/efi/efi.c
+++ b/arch/x86/platform/efi/efi.c
@@ -117,6 +117,27 @@ void efi_get_time(struct timespec *now)
 	now->tv_nsec = 0;
 }
 
+void __init efi_find_mirror(void)
+{
+	void *p;
+	u64 mirror_size = 0, total_size = 0;
+
+	for (p = memmap.map; p < memmap.map_end; p += memmap.desc_size) {
+		efi_memory_desc_t *md = p;
+		unsigned long long start = md->phys_addr;
+		unsigned long long size = md->num_pages << EFI_PAGE_SHIFT;
+
+		total_size += size;
+		if (md->attribute & EFI_MEMORY_MORE_RELIABLE) {
+			memblock_mark_mirror(start, size);
+			mirror_size += size;
+		}
+	}
+	if (mirror_size)
+		pr_info("Memory: %lldM/%lldM mirrored memory\n",
+			mirror_size>>20, total_size>>20);
+}
+
 /*
  * Tell the kernel about the EFI memory map.  This might include
  * more than the max 128 entries that can fit in the e820 legacy
diff --git a/arch/xtensa/include/asm/dma-mapping.h b/arch/xtensa/include/asm/dma-mapping.h
index ba78ccf651e7..1f5f6dc09736 100644
--- a/arch/xtensa/include/asm/dma-mapping.h
+++ b/arch/xtensa/include/asm/dma-mapping.h
@@ -52,14 +52,15 @@ dma_unmap_single(struct device *dev, dma_addr_t dma_addr, size_t size,
 }
 
 static inline int
-dma_map_sg(struct device *dev, struct scatterlist *sg, int nents,
+dma_map_sg(struct device *dev, struct scatterlist *sglist, int nents,
 	   enum dma_data_direction direction)
 {
 	int i;
+	struct scatterlist *sg;
 
 	BUG_ON(direction == DMA_NONE);
 
-	for (i = 0; i < nents; i++, sg++ ) {
+	for_each_sg(sglist, sg, nents, i) {
 		BUG_ON(!sg_page(sg));
 
 		sg->dma_address = sg_phys(sg);
@@ -124,20 +125,24 @@ dma_sync_single_range_for_device(struct device *dev, dma_addr_t dma_handle,
 	consistent_sync((void *)bus_to_virt(dma_handle)+offset,size,direction);
 }
 static inline void
-dma_sync_sg_for_cpu(struct device *dev, struct scatterlist *sg, int nelems,
+dma_sync_sg_for_cpu(struct device *dev, struct scatterlist *sglist, int nelems,
 		 enum dma_data_direction dir)
 {
 	int i;
-	for (i = 0; i < nelems; i++, sg++)
+	struct scatterlist *sg;
+
+	for_each_sg(sglist, sg, nelems, i)
 		consistent_sync(sg_virt(sg), sg->length, dir);
 }
 
 static inline void
-dma_sync_sg_for_device(struct device *dev, struct scatterlist *sg, int nelems,
-		 enum dma_data_direction dir)
+dma_sync_sg_for_device(struct device *dev, struct scatterlist *sglist,
+		       int nelems, enum dma_data_direction dir)
 {
 	int i;
-	for (i = 0; i < nelems; i++, sg++)
+	struct scatterlist *sg;
+
+	for_each_sg(sglist, sg, nelems, i)
 		consistent_sync(sg_virt(sg), sg->length, dir);
 }
 static inline int
diff --git a/arch/xtensa/include/asm/mm-arch-hooks.h b/arch/xtensa/include/asm/mm-arch-hooks.h
new file mode 100644
index 000000000000..d2e5cfd3dd02
--- /dev/null
+++ b/arch/xtensa/include/asm/mm-arch-hooks.h
@@ -0,0 +1,15 @@
+/*
+ * Architecture specific mm hooks
+ *
+ * Copyright (C) 2015, IBM Corporation
+ * Author: Laurent Dufour <ldufour@linux.vnet.ibm.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#ifndef _ASM_XTENSA_MM_ARCH_HOOKS_H
+#define _ASM_XTENSA_MM_ARCH_HOOKS_H
+
+#endif /* _ASM_XTENSA_MM_ARCH_HOOKS_H */