Merge branch 'akpm' (patches from Andrew)

Merge second set of updates from Andrew Morton:
 "More of MM"

* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (83 commits)
  mm/nommu.c: fix arithmetic overflow in __vm_enough_memory()
  mm/mmap.c: fix arithmetic overflow in __vm_enough_memory()
  vmstat: Reduce time interval to stat update on idle cpu
  mm/page_owner.c: remove unnecessary stack_trace field
  Documentation/filesystems/proc.txt: describe /proc/<pid>/map_files
  mm: incorporate read-only pages into transparent huge pages
  vmstat: do not use deferrable delayed work for vmstat_update
  mm: more aggressive page stealing for UNMOVABLE allocations
  mm: always steal split buddies in fallback allocations
  mm: when stealing freepages, also take pages created by splitting buddy page
  mincore: apply page table walker on do_mincore()
  mm: /proc/pid/clear_refs: avoid split_huge_page()
  mm: pagewalk: fix misbehavior of walk_page_range for vma(VM_PFNMAP)
  mempolicy: apply page table walker on queue_pages_range()
  arch/powerpc/mm/subpage-prot.c: use walk->vma and walk_page_vma()
  memcg: cleanup preparation for page table walk
  numa_maps: remove numa_maps->vma
  numa_maps: fix typo in gather_hugetbl_stats
  pagemap: use walk->vma instead of calling find_vma()
  clear_refs: remove clear_refs_private->vma and introduce clear_refs_test_walk()
  ...

50 files changed, 81 insertions, 188 deletions

diff --git a/arch/alpha/include/asm/pgtable.h b/arch/alpha/include/asm/pgtable.h
index fce22cf..a9a1195 100644
--- a/arch/alpha/include/asm/pgtable.h
+++ b/arch/alpha/include/asm/pgtable.h
@@ -45,7 +45,7 @@ struct vm_area_struct;
 #define PTRS_PER_PMD	(1UL << (PAGE_SHIFT-3))
 #define PTRS_PER_PGD	(1UL << (PAGE_SHIFT-3))
 #define USER_PTRS_PER_PGD	(TASK_SIZE / PGDIR_SIZE)
-#define FIRST_USER_ADDRESS	0
+#define FIRST_USER_ADDRESS	0UL
 
 /* Number of pointers that fit on a page:  this will go away. */
 #define PTRS_PER_PAGE	(1UL << (PAGE_SHIFT-3))
diff --git a/arch/arc/include/asm/pgtable.h b/arch/arc/include/asm/pgtable.h
index bdc8cca..ffed3b2 100644
--- a/arch/arc/include/asm/pgtable.h
+++ b/arch/arc/include/asm/pgtable.h
@@ -211,7 +211,7 @@
  * No special requirements for lowest virtual address we permit any user space
  * mapping to be mapped at.
  */
-#define FIRST_USER_ADDRESS      0
+#define FIRST_USER_ADDRESS      0UL
 
 
 /****************************************************************
diff --git a/arch/arm/include/asm/pgtable-2level.h b/arch/arm/include/asm/pgtable-2level.h
index bcc5e30..bfd662e 100644
--- a/arch/arm/include/asm/pgtable-2level.h
+++ b/arch/arm/include/asm/pgtable-2level.h
@@ -10,6 +10,8 @@
 #ifndef _ASM_PGTABLE_2LEVEL_H
 #define _ASM_PGTABLE_2LEVEL_H
 
+#define __PAGETABLE_PMD_FOLDED
+
 /*
  * Hardware-wise, we have a two level page table structure, where the first
  * level has 4096 entries, and the second level has 256 entries.  Each entry
diff --git a/arch/arm/include/asm/pgtable-nommu.h b/arch/arm/include/asm/pgtable-nommu.h
index c35e53e..add094d 100644
--- a/arch/arm/include/asm/pgtable-nommu.h
+++ b/arch/arm/include/asm/pgtable-nommu.h
@@ -85,7 +85,7 @@ extern unsigned int kobjsize(const void *objp);
 #define	VMALLOC_START	0UL
 #define	VMALLOC_END	0xffffffffUL
 
-#define FIRST_USER_ADDRESS      (0)
+#define FIRST_USER_ADDRESS      0UL
 
 #include <asm-generic/pgtable.h>
 
diff --git a/arch/arm/mm/hugetlbpage.c b/arch/arm/mm/hugetlbpage.c
index 66781bf3..c724124 100644
--- a/arch/arm/mm/hugetlbpage.c
+++ b/arch/arm/mm/hugetlbpage.c
@@ -36,12 +36,6 @@
  * of type casting from pmd_t * to pte_t *.
  */
 
-struct page *follow_huge_addr(struct mm_struct *mm, unsigned long address,
-			      int write)
-{
-	return ERR_PTR(-EINVAL);
-}
-
 int pud_huge(pud_t pud)
 {
 	return 0;
diff --git a/arch/arm/mm/pgd.c b/arch/arm/mm/pgd.c
index 2493795..a3681f1 100644
--- a/arch/arm/mm/pgd.c
+++ b/arch/arm/mm/pgd.c
@@ -97,6 +97,7 @@ pgd_t *pgd_alloc(struct mm_struct *mm)
 
 no_pte:
 	pmd_free(mm, new_pmd);
+	mm_dec_nr_pmds(mm);
 no_pmd:
 	pud_free(mm, new_pud);
 no_pud:
@@ -130,9 +131,11 @@ void pgd_free(struct mm_struct *mm, pgd_t *pgd_base)
 	pte = pmd_pgtable(*pmd);
 	pmd_clear(pmd);
 	pte_free(mm, pte);
+	atomic_long_dec(&mm->nr_ptes);
 no_pmd:
 	pud_clear(pud);
 	pmd_free(mm, pmd);
+	mm_dec_nr_pmds(mm);
 no_pud:
 	pgd_clear(pgd);
 	pud_free(mm, pud);
@@ -152,6 +155,7 @@ no_pgd:
 		pmd = pmd_offset(pud, 0);
 		pud_clear(pud);
 		pmd_free(mm, pmd);
+		mm_dec_nr_pmds(mm);
 		pgd_clear(pgd);
 		pud_free(mm, pud);
 	}
diff --git a/arch/arm64/include/asm/pgtable.h b/arch/arm64/include/asm/pgtable.h
index cf1d9c8..16449c535 100644
--- a/arch/arm64/include/asm/pgtable.h
+++ b/arch/arm64/include/asm/pgtable.h
@@ -45,7 +45,7 @@
 
 #define vmemmap			((struct page *)(VMALLOC_END + SZ_64K))
 
-#define FIRST_USER_ADDRESS	0
+#define FIRST_USER_ADDRESS	0UL
 
 #ifndef __ASSEMBLY__
 extern void __pte_error(const char *file, int line, unsigned long val);
diff --git a/arch/arm64/mm/hugetlbpage.c b/arch/arm64/mm/hugetlbpage.c
index 023747b..2de9d2e 100644
--- a/arch/arm64/mm/hugetlbpage.c
+++ b/arch/arm64/mm/hugetlbpage.c
@@ -38,12 +38,6 @@ int huge_pmd_unshare(struct mm_struct *mm, unsigned long *addr, pte_t *ptep)
 }
 #endif
 
-struct page *follow_huge_addr(struct mm_struct *mm, unsigned long address,
-			      int write)
-{
-	return ERR_PTR(-EINVAL);
-}
-
 int pmd_huge(pmd_t pmd)
 {
 	return !(pmd_val(pmd) & PMD_TABLE_BIT);
diff --git a/arch/avr32/include/asm/pgtable.h b/arch/avr32/include/asm/pgtable.h
index ac7a817..3580066 100644
--- a/arch/avr32/include/asm/pgtable.h
+++ b/arch/avr32/include/asm/pgtable.h
@@ -30,7 +30,7 @@
 #define PGDIR_MASK	(~(PGDIR_SIZE-1))
 
 #define USER_PTRS_PER_PGD	(TASK_SIZE / PGDIR_SIZE)
-#define FIRST_USER_ADDRESS	0
+#define FIRST_USER_ADDRESS	0UL
 
 #ifndef __ASSEMBLY__
 extern pgd_t swapper_pg_dir[PTRS_PER_PGD];
diff --git a/arch/cris/include/asm/pgtable.h b/arch/cris/include/asm/pgtable.h
index e824257..ceefc31 100644
--- a/arch/cris/include/asm/pgtable.h
+++ b/arch/cris/include/asm/pgtable.h
@@ -67,7 +67,7 @@ extern void paging_init(void);
  */
 
 #define USER_PTRS_PER_PGD       (TASK_SIZE/PGDIR_SIZE)
-#define FIRST_USER_ADDRESS      0
+#define FIRST_USER_ADDRESS      0UL
 
 /* zero page used for uninitialized stuff */
 #ifndef __ASSEMBLY__
diff --git a/arch/frv/include/asm/pgtable.h b/arch/frv/include/asm/pgtable.h
index c49699d..93bcf2a 100644
--- a/arch/frv/include/asm/pgtable.h
+++ b/arch/frv/include/asm/pgtable.h
@@ -140,7 +140,7 @@ extern unsigned long empty_zero_page;
 #define PTRS_PER_PTE		4096
 
 #define USER_PGDS_IN_LAST_PML4	(TASK_SIZE / PGDIR_SIZE)
-#define FIRST_USER_ADDRESS	0
+#define FIRST_USER_ADDRESS	0UL
 
 #define USER_PGD_PTRS		(PAGE_OFFSET >> PGDIR_SHIFT)
 #define KERNEL_PGD_PTRS		(PTRS_PER_PGD - USER_PGD_PTRS)
diff --git a/arch/hexagon/include/asm/pgtable.h b/arch/hexagon/include/asm/pgtable.h
index 6e35e71..49eab81 100644
--- a/arch/hexagon/include/asm/pgtable.h
+++ b/arch/hexagon/include/asm/pgtable.h
@@ -171,7 +171,7 @@ extern unsigned long _dflt_cache_att;
 extern pgd_t swapper_pg_dir[PTRS_PER_PGD];  /* located in head.S */
 
 /* Seems to be zero even in architectures where the zero page is firewalled? */
-#define FIRST_USER_ADDRESS 0
+#define FIRST_USER_ADDRESS 0UL
 #define pte_special(pte)	0
 #define pte_mkspecial(pte)	(pte)
 
diff --git a/arch/ia64/include/asm/pgtable.h b/arch/ia64/include/asm/pgtable.h
index 2f07bb3..7b6f880 100644
--- a/arch/ia64/include/asm/pgtable.h
+++ b/arch/ia64/include/asm/pgtable.h
@@ -127,7 +127,7 @@
 #define PTRS_PER_PGD_SHIFT	PTRS_PER_PTD_SHIFT
 #define PTRS_PER_PGD		(1UL << PTRS_PER_PGD_SHIFT)
 #define USER_PTRS_PER_PGD	(5*PTRS_PER_PGD/8)	/* regions 0-4 are user regions */
-#define FIRST_USER_ADDRESS	0
+#define FIRST_USER_ADDRESS	0UL
 
 /*
  * All the normal masks have the "page accessed" bits on, as any time
diff --git a/arch/ia64/mm/hugetlbpage.c b/arch/ia64/mm/hugetlbpage.c
index 76069c1..52b7604 100644
--- a/arch/ia64/mm/hugetlbpage.c
+++ b/arch/ia64/mm/hugetlbpage.c
@@ -114,12 +114,6 @@ int pud_huge(pud_t pud)
 	return 0;
 }
 
-struct page *
-follow_huge_pmd(struct mm_struct *mm, unsigned long address, pmd_t *pmd, int write)
-{
-	return NULL;
-}
-
 void hugetlb_free_pgd_range(struct mmu_gather *tlb,
 			unsigned long addr, unsigned long end,
 			unsigned long floor, unsigned long ceiling)
diff --git a/arch/m32r/include/asm/pgtable.h b/arch/m32r/include/asm/pgtable.h
index 050f7a6..8c1fb90 100644
--- a/arch/m32r/include/asm/pgtable.h
+++ b/arch/m32r/include/asm/pgtable.h
@@ -53,7 +53,7 @@ extern unsigned long empty_zero_page[1024];
 #define PGDIR_MASK	(~(PGDIR_SIZE - 1))
 
 #define USER_PTRS_PER_PGD	(TASK_SIZE / PGDIR_SIZE)
-#define FIRST_USER_ADDRESS	0
+#define FIRST_USER_ADDRESS	0UL
 
 #ifndef __ASSEMBLY__
 /* Just any arbitrary offset to the start of the vmalloc VM area: the
diff --git a/arch/m68k/include/asm/pgtable_mm.h b/arch/m68k/include/asm/pgtable_mm.h
index 9f5abbd..28a145b 100644
--- a/arch/m68k/include/asm/pgtable_mm.h
+++ b/arch/m68k/include/asm/pgtable_mm.h
@@ -66,7 +66,7 @@
 #define PTRS_PER_PGD	128
 #endif
 #define USER_PTRS_PER_PGD	(TASK_SIZE/PGDIR_SIZE)
-#define FIRST_USER_ADDRESS	0
+#define FIRST_USER_ADDRESS	0UL
 
 /* Virtual address region for use by kernel_map() */
 #ifdef CONFIG_SUN3
diff --git a/arch/metag/mm/hugetlbpage.c b/arch/metag/mm/hugetlbpage.c
index 3c32075..7ca80ac 100644
--- a/arch/metag/mm/hugetlbpage.c
+++ b/arch/metag/mm/hugetlbpage.c
@@ -94,12 +94,6 @@ int huge_pmd_unshare(struct mm_struct *mm, unsigned long *addr, pte_t *ptep)
 	return 0;
 }
 
-struct page *follow_huge_addr(struct mm_struct *mm,
-			      unsigned long address, int write)
-{
-	return ERR_PTR(-EINVAL);
-}
-
 int pmd_huge(pmd_t pmd)
 {
 	return pmd_page_shift(pmd) > PAGE_SHIFT;
diff --git a/arch/microblaze/include/asm/pgtable.h b/arch/microblaze/include/asm/pgtable.h
index 91b9b46..e53b853 100644
--- a/arch/microblaze/include/asm/pgtable.h
+++ b/arch/microblaze/include/asm/pgtable.h
@@ -61,6 +61,8 @@ extern int mem_init_done;
 
 #include <asm-generic/4level-fixup.h>
 
+#define __PAGETABLE_PMD_FOLDED
+
 #ifdef __KERNEL__
 #ifndef __ASSEMBLY__
 
@@ -70,7 +72,7 @@ extern int mem_init_done;
 #include <asm/mmu.h>
 #include <asm/page.h>
 
-#define FIRST_USER_ADDRESS	0
+#define FIRST_USER_ADDRESS	0UL
 
 extern unsigned long va_to_phys(unsigned long address);
 extern pte_t *va_to_pte(unsigned long address);
diff --git a/arch/mips/include/asm/pgtable-32.h b/arch/mips/include/asm/pgtable-32.h
index 16aa9f2..a6be006 100644
--- a/arch/mips/include/asm/pgtable-32.h
+++ b/arch/mips/include/asm/pgtable-32.h
@@ -57,7 +57,7 @@ extern int add_temporary_entry(unsigned long entrylo0, unsigned long entrylo1,
 #define PTRS_PER_PTE	((PAGE_SIZE << PTE_ORDER) / sizeof(pte_t))
 
 #define USER_PTRS_PER_PGD	(0x80000000UL/PGDIR_SIZE)
-#define FIRST_USER_ADDRESS	0
+#define FIRST_USER_ADDRESS	0UL
 
 #define VMALLOC_START	  MAP_BASE
 
diff --git a/arch/mips/mm/gup.c b/arch/mips/mm/gup.c
index 70795a6..349995d 100644
--- a/arch/mips/mm/gup.c
+++ b/arch/mips/mm/gup.c
@@ -301,11 +301,9 @@ slow_irqon:
 	start += nr << PAGE_SHIFT;
 	pages += nr;
 
-	down_read(&mm->mmap_sem);
-	ret = get_user_pages(current, mm, start,
-				(end - start) >> PAGE_SHIFT,
-				write, 0, pages, NULL);
-	up_read(&mm->mmap_sem);
+	ret = get_user_pages_unlocked(current, mm, start,
+				      (end - start) >> PAGE_SHIFT,
+				      write, 0, pages);
 
 	/* Have to be a bit careful with return values */
 	if (nr > 0) {
diff --git a/arch/mips/mm/hugetlbpage.c b/arch/mips/mm/hugetlbpage.c
index 4ec8ee1..06e0f42 100644
--- a/arch/mips/mm/hugetlbpage.c
+++ b/arch/mips/mm/hugetlbpage.c
@@ -68,12 +68,6 @@ int is_aligned_hugepage_range(unsigned long addr, unsigned long len)
 	return 0;
 }
 
-struct page *
-follow_huge_addr(struct mm_struct *mm, unsigned long address, int write)
-{
-	return ERR_PTR(-EINVAL);
-}
-
 int pmd_huge(pmd_t pmd)
 {
 	return (pmd_val(pmd) & _PAGE_HUGE) != 0;
@@ -83,15 +77,3 @@ int pud_huge(pud_t pud)
 {
 	return (pud_val(pud) & _PAGE_HUGE) != 0;
 }
-
-struct page *
-follow_huge_pmd(struct mm_struct *mm, unsigned long address,
-		pmd_t *pmd, int write)
-{
-	struct page *page;
-
-	page = pte_page(*(pte_t *)pmd);
-	if (page)
-		page += ((address & ~HPAGE_MASK) >> PAGE_SHIFT);
-	return page;
-}
diff --git a/arch/mn10300/include/asm/pgtable.h b/arch/mn10300/include/asm/pgtable.h
index 629181a..afab728 100644
--- a/arch/mn10300/include/asm/pgtable.h
+++ b/arch/mn10300/include/asm/pgtable.h
@@ -65,7 +65,7 @@ extern void paging_init(void);
 #define PGDIR_MASK	(~(PGDIR_SIZE - 1))
 
 #define USER_PTRS_PER_PGD	(TASK_SIZE / PGDIR_SIZE)
-#define FIRST_USER_ADDRESS	0
+#define FIRST_USER_ADDRESS	0UL
 
 #define USER_PGD_PTRS		(PAGE_OFFSET >> PGDIR_SHIFT)
 #define KERNEL_PGD_PTRS		(PTRS_PER_PGD - USER_PGD_PTRS)
diff --git a/arch/nios2/include/asm/pgtable.h b/arch/nios2/include/asm/pgtable.h
index 7b292e3..a213e8c 100644
--- a/arch/nios2/include/asm/pgtable.h
+++ b/arch/nios2/include/asm/pgtable.h
@@ -24,7 +24,7 @@
 #include <asm/pgtable-bits.h>
 #include <asm-generic/pgtable-nopmd.h>
 
-#define FIRST_USER_ADDRESS	0
+#define FIRST_USER_ADDRESS	0UL
 
 #define VMALLOC_START		CONFIG_NIOS2_KERNEL_MMU_REGION_BASE
 #define VMALLOC_END		(CONFIG_NIOS2_KERNEL_REGION_BASE - 1)
diff --git a/arch/openrisc/include/asm/pgtable.h b/arch/openrisc/include/asm/pgtable.h
index 18994cc..69c7df0 100644
--- a/arch/openrisc/include/asm/pgtable.h
+++ b/arch/openrisc/include/asm/pgtable.h
@@ -77,7 +77,7 @@ extern void paging_init(void);
  */
 
 #define USER_PTRS_PER_PGD       (TASK_SIZE/PGDIR_SIZE)
-#define FIRST_USER_ADDRESS      0
+#define FIRST_USER_ADDRESS      0UL
 
 /*
  * Kernels own virtual memory area.
diff --git a/arch/parisc/include/asm/pgtable.h b/arch/parisc/include/asm/pgtable.h
index 1d49a4a..8c966b2 100644
--- a/arch/parisc/include/asm/pgtable.h
+++ b/arch/parisc/include/asm/pgtable.h
@@ -134,7 +134,7 @@ extern void purge_tlb_entries(struct mm_struct *, unsigned long);
  * pgd entries used up by user/kernel:
  */
 
-#define FIRST_USER_ADDRESS	0
+#define FIRST_USER_ADDRESS	0UL
 
 /* NB: The tlb miss handlers make certain assumptions about the order */
 /*     of the following bits, so be careful (One example, bits 25-31  */
diff --git a/arch/powerpc/include/asm/pgtable-ppc32.h b/arch/powerpc/include/asm/pgtable-ppc32.h
index 26ce0ab..14bdcbd 100644
--- a/arch/powerpc/include/asm/pgtable-ppc32.h
+++ b/arch/powerpc/include/asm/pgtable-ppc32.h
@@ -45,7 +45,7 @@ extern int icache_44x_need_flush;
 #define PTRS_PER_PGD	(1 << (32 - PGDIR_SHIFT))
 
 #define USER_PTRS_PER_PGD	(TASK_SIZE / PGDIR_SIZE)
-#define FIRST_USER_ADDRESS	0
+#define FIRST_USER_ADDRESS	0UL
 
 #define pte_ERROR(e) \
 	pr_err("%s:%d: bad pte %llx.\n", __FILE__, __LINE__, \
diff --git a/arch/powerpc/include/asm/pgtable-ppc64.h b/arch/powerpc/include/asm/pgtable-ppc64.h
index b9dcc93..d46532c 100644
--- a/arch/powerpc/include/asm/pgtable-ppc64.h
+++ b/arch/powerpc/include/asm/pgtable-ppc64.h
@@ -12,7 +12,7 @@
 #endif
 #include <asm/barrier.h>
 
-#define FIRST_USER_ADDRESS	0
+#define FIRST_USER_ADDRESS	0UL
 
 /*
  * Size of EA range mapped by our pagetables.
diff --git a/arch/powerpc/mm/hugetlbpage.c b/arch/powerpc/mm/hugetlbpage.c
index 5ff4e07..cf0464f 100644
--- a/arch/powerpc/mm/hugetlbpage.c
+++ b/arch/powerpc/mm/hugetlbpage.c
@@ -714,6 +714,14 @@ follow_huge_pmd(struct mm_struct *mm, unsigned long address,
 	return NULL;
 }
 
+struct page *
+follow_huge_pud(struct mm_struct *mm, unsigned long address,
+		pud_t *pud, int write)
+{
+	BUG();
+	return NULL;
+}
+
 static unsigned long hugepte_addr_end(unsigned long addr, unsigned long end,
 				      unsigned long sz)
 {
diff --git a/arch/powerpc/mm/subpage-prot.c b/arch/powerpc/mm/subpage-prot.c
index 6c0b1f5..fa9fb5b 100644
--- a/arch/powerpc/mm/subpage-prot.c
+++ b/arch/powerpc/mm/subpage-prot.c
@@ -134,7 +134,7 @@ static void subpage_prot_clear(unsigned long addr, unsigned long len)
 static int subpage_walk_pmd_entry(pmd_t *pmd, unsigned long addr,
 				  unsigned long end, struct mm_walk *walk)
 {
-	struct vm_area_struct *vma = walk->private;
+	struct vm_area_struct *vma = walk->vma;
 	split_huge_page_pmd(vma, addr, pmd);
 	return 0;
 }
@@ -163,9 +163,7 @@ static void subpage_mark_vma_nohuge(struct mm_struct *mm, unsigned long addr,
 		if (vma->vm_start >= (addr + len))
 			break;
 		vma->vm_flags |= VM_NOHUGEPAGE;
-		subpage_proto_walk.private = vma;
-		walk_page_range(vma->vm_start, vma->vm_end,
-				&subpage_proto_walk);
+		walk_page_vma(vma, &subpage_proto_walk);
 		vma = vma->vm_next;
 	}
 }
diff --git a/arch/s390/include/asm/pgtable.h b/arch/s390/include/asm/pgtable.h
index 0441ec2..fbb5ee3 100644
--- a/arch/s390/include/asm/pgtable.h
+++ b/arch/s390/include/asm/pgtable.h
@@ -99,7 +99,7 @@ extern unsigned long zero_page_mask;
 #endif /* CONFIG_64BIT */
 #define PTRS_PER_PGD	2048
 
-#define FIRST_USER_ADDRESS  0
+#define FIRST_USER_ADDRESS  0UL
 
 #define pte_ERROR(e) \
 	printk("%s:%d: bad pte %p.\n", __FILE__, __LINE__, (void *) pte_val(e))
diff --git a/arch/s390/mm/gup.c b/arch/s390/mm/gup.c
index 639fce46..5c586c7 100644
--- a/arch/s390/mm/gup.c
+++ b/arch/s390/mm/gup.c
@@ -235,10 +235,8 @@ int get_user_pages_fast(unsigned long start, int nr_pages, int write,
 	/* Try to get the remaining pages with get_user_pages */
 	start += nr << PAGE_SHIFT;
 	pages += nr;
-	down_read(&mm->mmap_sem);
-	ret = get_user_pages(current, mm, start,
-			     nr_pages - nr, write, 0, pages, NULL);
-	up_read(&mm->mmap_sem);
+	ret = get_user_pages_unlocked(current, mm, start,
+			     nr_pages - nr, write, 0, pages);
 	/* Have to be a bit careful with return values */
 	if (nr > 0)
 		ret = (ret < 0) ? nr : ret + nr;
diff --git a/arch/s390/mm/hugetlbpage.c b/arch/s390/mm/hugetlbpage.c
index 3c80d2e..210ffed 100644
--- a/arch/s390/mm/hugetlbpage.c
+++ b/arch/s390/mm/hugetlbpage.c
@@ -192,12 +192,6 @@ int huge_pmd_unshare(struct mm_struct *mm, unsigned long *addr, pte_t *ptep)
 	return 0;
 }
 
-struct page *follow_huge_addr(struct mm_struct *mm, unsigned long address,
-			      int write)
-{
-	return ERR_PTR(-EINVAL);
-}
-
 int pmd_huge(pmd_t pmd)
 {
 	if (!MACHINE_HAS_HPAGE)
@@ -210,17 +204,3 @@ int pud_huge(pud_t pud)
 {
 	return 0;
 }
-
-struct page *follow_huge_pmd(struct mm_struct *mm, unsigned long address,
-			     pmd_t *pmdp, int write)
-{
-	struct page *page;
-
-	if (!MACHINE_HAS_HPAGE)
-		return NULL;
-
-	page = pmd_page(*pmdp);
-	if (page)
-		page += ((address & ~HPAGE_MASK) >> PAGE_SHIFT);
-	return page;
-}
diff --git a/arch/score/include/asm/pgtable.h b/arch/score/include/asm/pgtable.h
index 5170ffd..0553e5c 100644
--- a/arch/score/include/asm/pgtable.h
+++ b/arch/score/include/asm/pgtable.h
@@ -27,7 +27,7 @@ extern pte_t invalid_pte_table[PAGE_SIZE/sizeof(pte_t)];
 #define PTRS_PER_PTE	1024
 
 #define USER_PTRS_PER_PGD	(0x80000000UL/PGDIR_SIZE)
-#define FIRST_USER_ADDRESS	0
+#define FIRST_USER_ADDRESS	0UL
 
 #define VMALLOC_START		(0xc0000000UL)
 
diff --git a/arch/sh/include/asm/pgtable.h b/arch/sh/include/asm/pgtable.h
index cf434c6..89c513a 100644
--- a/arch/sh/include/asm/pgtable.h
+++ b/arch/sh/include/asm/pgtable.h
@@ -62,7 +62,7 @@ static inline unsigned long long neff_sign_extend(unsigned long val)
 /* Entries per level */
 #define PTRS_PER_PTE	(PAGE_SIZE / (1 << PTE_MAGNITUDE))
 
-#define FIRST_USER_ADDRESS	0
+#define FIRST_USER_ADDRESS	0UL
 
 #define PHYS_ADDR_MASK29		0x1fffffff
 #define PHYS_ADDR_MASK32		0xffffffff
diff --git a/arch/sh/mm/gup.c b/arch/sh/mm/gup.c
index 37458f3..e15f52a 100644
--- a/arch/sh/mm/gup.c
+++ b/arch/sh/mm/gup.c
@@ -257,10 +257,8 @@ slow_irqon:
 		start += nr << PAGE_SHIFT;
 		pages += nr;
 
-		down_read(&mm->mmap_sem);
-		ret = get_user_pages(current, mm, start,
-			(end - start) >> PAGE_SHIFT, write, 0, pages, NULL);
-		up_read(&mm->mmap_sem);
+		ret = get_user_pages_unlocked(current, mm, start,
+			(end - start) >> PAGE_SHIFT, write, 0, pages);
 
 		/* Have to be a bit careful with return values */
 		if (nr > 0) {
diff --git a/arch/sh/mm/hugetlbpage.c b/arch/sh/mm/hugetlbpage.c
index d776234..534bc97 100644
--- a/arch/sh/mm/hugetlbpage.c
+++ b/arch/sh/mm/hugetlbpage.c
@@ -67,12 +67,6 @@ int huge_pmd_unshare(struct mm_struct *mm, unsigned long *addr, pte_t *ptep)
 	return 0;
 }
 
-struct page *follow_huge_addr(struct mm_struct *mm,
-			      unsigned long address, int write)
-{
-	return ERR_PTR(-EINVAL);
-}
-
 int pmd_huge(pmd_t pmd)
 {
 	return 0;
@@ -82,9 +76,3 @@ int pud_huge(pud_t pud)
 {
 	return 0;
 }
-
-struct page *follow_huge_pmd(struct mm_struct *mm, unsigned long address,
-			     pmd_t *pmd, int write)
-{
-	return NULL;
-}
diff --git a/arch/sparc/include/asm/pgtable_32.h b/arch/sparc/include/asm/pgtable_32.h
index b2f7dc4..f06b36a 100644
--- a/arch/sparc/include/asm/pgtable_32.h
+++ b/arch/sparc/include/asm/pgtable_32.h
@@ -44,7 +44,7 @@ unsigned long __init bootmem_init(unsigned long *pages_avail);
 #define PTRS_PER_PMD    	SRMMU_PTRS_PER_PMD
 #define PTRS_PER_PGD    	SRMMU_PTRS_PER_PGD
 #define USER_PTRS_PER_PGD	PAGE_OFFSET / SRMMU_PGDIR_SIZE
-#define FIRST_USER_ADDRESS	0
+#define FIRST_USER_ADDRESS	0UL
 #define PTE_SIZE		(PTRS_PER_PTE*4)
 
 #define PAGE_NONE	SRMMU_PAGE_NONE
@@ -102,7 +102,8 @@ extern unsigned long empty_zero_page;
  */
 static inline unsigned long srmmu_swap(unsigned long *addr, unsigned long value)
 {
-	__asm__ __volatile__("swap [%2], %0" : "=&r" (value) : "0" (value), "r" (addr));
+	__asm__ __volatile__("swap [%2], %0" :
+			"=&r" (value) : "0" (value), "r" (addr) : "memory");
 	return value;
 }
 
diff --git a/arch/sparc/include/asm/pgtable_64.h b/arch/sparc/include/asm/pgtable_64.h
index 2ac7873..dc165eb 100644
--- a/arch/sparc/include/asm/pgtable_64.h
+++ b/arch/sparc/include/asm/pgtable_64.h
@@ -93,7 +93,7 @@ bool kern_addr_valid(unsigned long addr);
 #define PTRS_PER_PGD	(1UL << PGDIR_BITS)
 
 /* Kernel has a separate 44bit address space. */
-#define FIRST_USER_ADDRESS	0
+#define FIRST_USER_ADDRESS	0UL
 
 #define pmd_ERROR(e)							\
 	pr_err("%s:%d: bad pmd %p(%016lx) seen at (%pS)\n",		\
diff --git a/arch/sparc/mm/gup.c b/arch/sparc/mm/gup.c
index ae6ce38..2e5c4fc 100644
--- a/arch/sparc/mm/gup.c
+++ b/arch/sparc/mm/gup.c
@@ -249,10 +249,8 @@ slow:
 		start += nr << PAGE_SHIFT;
 		pages += nr;
 
-		down_read(&mm->mmap_sem);
-		ret = get_user_pages(current, mm, start,
-			(end - start) >> PAGE_SHIFT, write, 0, pages, NULL);
-		up_read(&mm->mmap_sem);
+		ret = get_user_pages_unlocked(current, mm, start,
+			(end - start) >> PAGE_SHIFT, write, 0, pages);
 
 		/* Have to be a bit careful with return values */
 		if (nr > 0) {
diff --git a/arch/sparc/mm/hugetlbpage.c b/arch/sparc/mm/hugetlbpage.c
index d329537..4242eab 100644
--- a/arch/sparc/mm/hugetlbpage.c
+++ b/arch/sparc/mm/hugetlbpage.c
@@ -215,12 +215,6 @@ pte_t huge_ptep_get_and_clear(struct mm_struct *mm, unsigned long addr,
 	return entry;
 }
 
-struct page *follow_huge_addr(struct mm_struct *mm,
-			      unsigned long address, int write)
-{
-	return ERR_PTR(-EINVAL);
-}
-
 int pmd_huge(pmd_t pmd)
 {
 	return 0;
@@ -230,9 +224,3 @@ int pud_huge(pud_t pud)
 {
 	return 0;
 }
-
-struct page *follow_huge_pmd(struct mm_struct *mm, unsigned long address,
-			     pmd_t *pmd, int write)
-{
-	return NULL;
-}
diff --git a/arch/tile/include/asm/pgtable.h b/arch/tile/include/asm/pgtable.h
index bc75b6e..95a4f19 100644
--- a/arch/tile/include/asm/pgtable.h
+++ b/arch/tile/include/asm/pgtable.h
@@ -67,7 +67,7 @@ extern void pgtable_cache_init(void);
 extern void paging_init(void);
 extern void set_page_homes(void);
 
-#define FIRST_USER_ADDRESS	0
+#define FIRST_USER_ADDRESS	0UL
 
 #define _PAGE_PRESENT           HV_PTE_PRESENT
 #define _PAGE_HUGE_PAGE         HV_PTE_PAGE
diff --git a/arch/tile/mm/hugetlbpage.c b/arch/tile/mm/hugetlbpage.c
index 3270e00..8416240 100644
--- a/arch/tile/mm/hugetlbpage.c
+++ b/arch/tile/mm/hugetlbpage.c
@@ -150,12 +150,6 @@ pte_t *huge_pte_offset(struct mm_struct *mm, unsigned long addr)
 	return NULL;
 }
 
-struct page *follow_huge_addr(struct mm_struct *mm, unsigned long address,
-			      int write)
-{
-	return ERR_PTR(-EINVAL);
-}
-
 int pmd_huge(pmd_t pmd)
 {
 	return !!(pmd_val(pmd) & _PAGE_HUGE_PAGE);
@@ -166,28 +160,6 @@ int pud_huge(pud_t pud)
 	return !!(pud_val(pud) & _PAGE_HUGE_PAGE);
 }
 
-struct page *follow_huge_pmd(struct mm_struct *mm, unsigned long address,
-			     pmd_t *pmd, int write)
-{
-	struct page *page;
-
-	page = pte_page(*(pte_t *)pmd);
-	if (page)
-		page += ((address & ~PMD_MASK) >> PAGE_SHIFT);
-	return page;
-}
-
-struct page *follow_huge_pud(struct mm_struct *mm, unsigned long address,
-			     pud_t *pud, int write)
-{
-	struct page *page;
-
-	page = pte_page(*(pte_t *)pud);
-	if (page)
-		page += ((address & ~PUD_MASK) >> PAGE_SHIFT);
-	return page;
-}
-
 int huge_pmd_unshare(struct mm_struct *mm, unsigned long *addr, pte_t *ptep)
 {
 	return 0;
diff --git a/arch/um/include/asm/pgtable-2level.h b/arch/um/include/asm/pgtable-2level.h
index 7afe860..cfbe597 100644
--- a/arch/um/include/asm/pgtable-2level.h
+++ b/arch/um/include/asm/pgtable-2level.h
@@ -23,7 +23,7 @@
 #define PTRS_PER_PTE	1024
 #define USER_PTRS_PER_PGD ((TASK_SIZE + (PGDIR_SIZE - 1)) / PGDIR_SIZE)
 #define PTRS_PER_PGD	1024
-#define FIRST_USER_ADDRESS	0
+#define FIRST_USER_ADDRESS	0UL
 
 #define pte_ERROR(e) \
         printk("%s:%d: bad pte %p(%08lx).\n", __FILE__, __LINE__, &(e), \
diff --git a/arch/um/include/asm/pgtable-3level.h b/arch/um/include/asm/pgtable-3level.h
index 344c559..2b4274e 100644
--- a/arch/um/include/asm/pgtable-3level.h
+++ b/arch/um/include/asm/pgtable-3level.h
@@ -41,7 +41,7 @@
 #endif
 
 #define USER_PTRS_PER_PGD ((TASK_SIZE + (PGDIR_SIZE - 1)) / PGDIR_SIZE)
-#define FIRST_USER_ADDRESS	0
+#define FIRST_USER_ADDRESS	0UL
 
 #define pte_ERROR(e) \
         printk("%s:%d: bad pte %p(%016lx).\n", __FILE__, __LINE__, &(e), \
diff --git a/arch/unicore32/mm/pgd.c b/arch/unicore32/mm/pgd.c
index 08b8d42..2ade20d 100644
--- a/arch/unicore32/mm/pgd.c
+++ b/arch/unicore32/mm/pgd.c
@@ -69,6 +69,7 @@ pgd_t *get_pgd_slow(struct mm_struct *mm)
 
 no_pte:
 	pmd_free(mm, new_pmd);
+	mm_dec_nr_pmds(mm);
 no_pmd:
 	free_pages((unsigned long)new_pgd, 0);
 no_pgd:
@@ -96,7 +97,9 @@ void free_pgd_slow(struct mm_struct *mm, pgd_t *pgd)
 	pte = pmd_pgtable(*pmd);
 	pmd_clear(pmd);
 	pte_free(mm, pte);
+	atomic_long_dec(&mm->nr_ptes);
 	pmd_free(mm, pmd);
+	mm_dec_nr_pmds(mm);
 free:
 	free_pages((unsigned long) pgd, 0);
 }
diff --git a/arch/x86/include/asm/pgtable_types.h b/arch/x86/include/asm/pgtable_types.h
index 5185a4f..3e0230c 100644
--- a/arch/x86/include/asm/pgtable_types.h
+++ b/arch/x86/include/asm/pgtable_types.h
@@ -4,7 +4,7 @@
 #include <linux/const.h>
 #include <asm/page_types.h>
 
-#define FIRST_USER_ADDRESS	0
+#define FIRST_USER_ADDRESS	0UL
 
 #define _PAGE_BIT_PRESENT	0	/* is present */
 #define _PAGE_BIT_RW		1	/* writeable */
diff --git a/arch/x86/mm/gup.c b/arch/x86/mm/gup.c
index d754782..89df70e 100644
--- a/arch/x86/mm/gup.c
+++ b/arch/x86/mm/gup.c
@@ -172,7 +172,7 @@ static int gup_pmd_range(pud_t pud, unsigned long addr, unsigned long end,
 		 */
 		if (pmd_none(pmd) || pmd_trans_splitting(pmd))
 			return 0;
-		if (unlikely(pmd_large(pmd))) {
+		if (unlikely(pmd_large(pmd) || !pmd_present(pmd))) {
 			/*
 			 * NUMA hinting faults need to be handled in the GUP
 			 * slowpath for accounting purposes and so that they
@@ -388,10 +388,9 @@ slow_irqon:
 		start += nr << PAGE_SHIFT;
 		pages += nr;
 
-		down_read(&mm->mmap_sem);
-		ret = get_user_pages(current, mm, start,
-			(end - start) >> PAGE_SHIFT, write, 0, pages, NULL);
-		up_read(&mm->mmap_sem);
+		ret = get_user_pages_unlocked(current, mm, start,
+					      (end - start) >> PAGE_SHIFT,
+					      write, 0, pages);
 
 		/* Have to be a bit careful with return values */
 		if (nr > 0) {
diff --git a/arch/x86/mm/hugetlbpage.c b/arch/x86/mm/hugetlbpage.c
index bca0aa3..42982b2 100644
--- a/arch/x86/mm/hugetlbpage.c
+++ b/arch/x86/mm/hugetlbpage.c
@@ -52,23 +52,17 @@ int pud_huge(pud_t pud)
 	return 0;
 }
 
-struct page *
-follow_huge_pmd(struct mm_struct *mm, unsigned long address,
-		pmd_t *pmd, int write)
-{
-	return NULL;
-}
 #else
 
-struct page *
-follow_huge_addr(struct mm_struct *mm, unsigned long address, int write)
-{
-	return ERR_PTR(-EINVAL);
-}
-
+/*
+ * pmd_huge() returns 1 if @pmd is hugetlb related entry, that is normal
+ * hugetlb entry or non-present (migration or hwpoisoned) hugetlb entry.
+ * Otherwise, returns 0.
+ */
 int pmd_huge(pmd_t pmd)
 {
-	return !!(pmd_val(pmd) & _PAGE_PSE);
+	return !pmd_none(pmd) &&
+		(pmd_val(pmd) & (_PAGE_PRESENT|_PAGE_PSE)) != _PAGE_PRESENT;
 }
 
 int pud_huge(pud_t pud)
diff --git a/arch/x86/mm/pgtable.c b/arch/x86/mm/pgtable.c
index 6fb6927..7b22ada 100644
--- a/arch/x86/mm/pgtable.c
+++ b/arch/x86/mm/pgtable.c
@@ -190,7 +190,7 @@ void pud_populate(struct mm_struct *mm, pud_t *pudp, pmd_t *pmd)
 
 #endif	/* CONFIG_X86_PAE */
 
-static void free_pmds(pmd_t *pmds[])
+static void free_pmds(struct mm_struct *mm, pmd_t *pmds[])
 {
 	int i;
 
@@ -198,10 +198,11 @@ static void free_pmds(pmd_t *pmds[])
 		if (pmds[i]) {
 			pgtable_pmd_page_dtor(virt_to_page(pmds[i]));
 			free_page((unsigned long)pmds[i]);
+			mm_dec_nr_pmds(mm);
 		}
 }
 
-static int preallocate_pmds(pmd_t *pmds[])
+static int preallocate_pmds(struct mm_struct *mm, pmd_t *pmds[])
 {
 	int i;
 	bool failed = false;
@@ -215,11 +216,13 @@ static int preallocate_pmds(pmd_t *pmds[])
 			pmd = NULL;
 			failed = true;
 		}
+		if (pmd)
+			mm_inc_nr_pmds(mm);
 		pmds[i] = pmd;
 	}
 
 	if (failed) {
-		free_pmds(pmds);
+		free_pmds(mm, pmds);
 		return -ENOMEM;
 	}
 
@@ -246,6 +249,7 @@ static void pgd_mop_up_pmds(struct mm_struct *mm, pgd_t *pgdp)
 
 			paravirt_release_pmd(pgd_val(pgd) >> PAGE_SHIFT);
 			pmd_free(mm, pmd);
+			mm_dec_nr_pmds(mm);
 		}
 	}
 }
@@ -283,7 +287,7 @@ pgd_t *pgd_alloc(struct mm_struct *mm)
 
 	mm->pgd = pgd;
 
-	if (preallocate_pmds(pmds) != 0)
+	if (preallocate_pmds(mm, pmds) != 0)
 		goto out_free_pgd;
 
 	if (paravirt_pgd_alloc(mm) != 0)
@@ -304,7 +308,7 @@ pgd_t *pgd_alloc(struct mm_struct *mm)
 	return pgd;
 
 out_free_pmds:
-	free_pmds(pmds);
+	free_pmds(mm, pmds);
 out_free_pgd:
 	free_page((unsigned long)pgd);
 out:
diff --git a/arch/xtensa/include/asm/pgtable.h b/arch/xtensa/include/asm/pgtable.h
index 01b80dc..a5e929a 100644
--- a/arch/xtensa/include/asm/pgtable.h
+++ b/arch/xtensa/include/asm/pgtable.h
@@ -57,7 +57,7 @@
 #define PTRS_PER_PGD		1024
 #define PGD_ORDER		0
 #define USER_PTRS_PER_PGD	(TASK_SIZE/PGDIR_SIZE)
-#define FIRST_USER_ADDRESS	0
+#define FIRST_USER_ADDRESS	0UL
 #define FIRST_USER_PGD_NR	(FIRST_USER_ADDRESS >> PGDIR_SHIFT)
 
 /*