Merge branch 'akpm' (patches from Andrew)

Mergr misc fixes from Andrew Morton:
 "28 fixes"

* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (28 commits)
  fs/hugetlbfs/inode.c: change put_page/unlock_page order in hugetlbfs_fallocate()
  mm/hugetlb: fix NULL-pointer dereference on 5-level paging machine
  autofs: revert "autofs: fix AT_NO_AUTOMOUNT not being honored"
  autofs: revert "autofs: take more care to not update last_used on path walk"
  fs/fat/inode.c: fix sb_rdonly() change
  mm, memcg: fix mem_cgroup_swapout() for THPs
  mm: migrate: fix an incorrect call of prep_transhuge_page()
  kmemleak: add scheduling point to kmemleak_scan()
  scripts/bloat-o-meter: don't fail with division by 0
  fs/mbcache.c: make count_objects() more robust
  Revert "mm/page-writeback.c: print a warning if the vm dirtiness settings are illogical"
  mm/madvise.c: fix madvise() infinite loop under special circumstances
  exec: avoid RLIMIT_STACK races with prlimit()
  IB/core: disable memory registration of filesystem-dax vmas
  v4l2: disable filesystem-dax mapping support
  mm: fail get_vaddr_frames() for filesystem-dax mappings
  mm: introduce get_user_pages_longterm
  device-dax: implement ->split() to catch invalid munmap attempts
  mm, hugetlbfs: introduce ->split() to vm_operations_struct
  scripts/faddr2line: extend usage on generic arch
  ...

5 files changed, 41 insertions, 12 deletions

diff --git a/include/asm-generic/pgtable.h b/include/asm-generic/pgtable.h
index 757dc6ffc7ba..b234d54f2cb6 100644
--- a/include/asm-generic/pgtable.h
+++ b/include/asm-generic/pgtable.h
@@ -805,15 +805,23 @@ static inline int pmd_trans_huge(pmd_t pmd)
 {
 	return 0;
 }
-#ifndef __HAVE_ARCH_PMD_WRITE
+#ifndef pmd_write
 static inline int pmd_write(pmd_t pmd)
 {
 	BUG();
 	return 0;
 }
-#endif /* __HAVE_ARCH_PMD_WRITE */
+#endif /* pmd_write */
 #endif /* CONFIG_TRANSPARENT_HUGEPAGE */
 
+#ifndef pud_write
+static inline int pud_write(pud_t pud)
+{
+	BUG();
+	return 0;
+}
+#endif /* pud_write */
+
 #if !defined(CONFIG_TRANSPARENT_HUGEPAGE) || \
 	(defined(CONFIG_TRANSPARENT_HUGEPAGE) && \
 	 !defined(CONFIG_HAVE_ARCH_TRANSPARENT_HUGEPAGE_PUD))
diff --git a/include/linux/fs.h b/include/linux/fs.h
index bbd92da0946e..511fbaabf624 100644
--- a/include/linux/fs.h
+++ b/include/linux/fs.h
@@ -3088,7 +3088,8 @@ static inline int vfs_lstat(const char __user *name, struct kstat *stat)
 static inline int vfs_fstatat(int dfd, const char __user *filename,
 			      struct kstat *stat, int flags)
 {
-	return vfs_statx(dfd, filename, flags, stat, STATX_BASIC_STATS);
+	return vfs_statx(dfd, filename, flags | AT_NO_AUTOMOUNT,
+			 stat, STATX_BASIC_STATS);
 }
 static inline int vfs_fstat(int fd, struct kstat *stat)
 {
@@ -3194,6 +3195,20 @@ static inline bool vma_is_dax(struct vm_area_struct *vma)
 	return vma->vm_file && IS_DAX(vma->vm_file->f_mapping->host);
 }
 
+static inline bool vma_is_fsdax(struct vm_area_struct *vma)
+{
+	struct inode *inode;
+
+	if (!vma->vm_file)
+		return false;
+	if (!vma_is_dax(vma))
+		return false;
+	inode = file_inode(vma->vm_file);
+	if (inode->i_mode == S_IFCHR)
+		return false; /* device-dax */
+	return true;
+}
+
 static inline int iocb_flags(struct file *file)
 {
 	int res = 0;
diff --git a/include/linux/hugetlb.h b/include/linux/hugetlb.h
index fbf5b31d47ee..82a25880714a 100644
--- a/include/linux/hugetlb.h
+++ b/include/linux/hugetlb.h
@@ -239,14 +239,6 @@ static inline int pgd_write(pgd_t pgd)
 }
 #endif
 
-#ifndef pud_write
-static inline int pud_write(pud_t pud)
-{
-	BUG();
-	return 0;
-}
-#endif
-
 #define HUGETLB_ANON_FILE "anon_hugepage"
 
 enum {
diff --git a/include/linux/migrate.h b/include/linux/migrate.h
index 895ec0c4942e..a2246cf670ba 100644
--- a/include/linux/migrate.h
+++ b/include/linux/migrate.h
@@ -54,7 +54,7 @@ static inline struct page *new_page_nodemask(struct page *page,
 	new_page = __alloc_pages_nodemask(gfp_mask, order,
 				preferred_nid, nodemask);
 
-	if (new_page && PageTransHuge(page))
+	if (new_page && PageTransHuge(new_page))
 		prep_transhuge_page(new_page);
 
 	return new_page;
diff --git a/include/linux/mm.h b/include/linux/mm.h
index ee073146aaa7..ea818ff739cd 100644
--- a/include/linux/mm.h
+++ b/include/linux/mm.h
@@ -377,6 +377,7 @@ enum page_entry_size {
 struct vm_operations_struct {
 	void (*open)(struct vm_area_struct * area);
 	void (*close)(struct vm_area_struct * area);
+	int (*split)(struct vm_area_struct * area, unsigned long addr);
 	int (*mremap)(struct vm_area_struct * area);
 	int (*fault)(struct vm_fault *vmf);
 	int (*huge_fault)(struct vm_fault *vmf, enum page_entry_size pe_size);
@@ -1379,6 +1380,19 @@ long get_user_pages_locked(unsigned long start, unsigned long nr_pages,
 		    unsigned int gup_flags, struct page **pages, int *locked);
 long get_user_pages_unlocked(unsigned long start, unsigned long nr_pages,
 		    struct page **pages, unsigned int gup_flags);
+#ifdef CONFIG_FS_DAX
+long get_user_pages_longterm(unsigned long start, unsigned long nr_pages,
+			    unsigned int gup_flags, struct page **pages,
+			    struct vm_area_struct **vmas);
+#else
+static inline long get_user_pages_longterm(unsigned long start,
+		unsigned long nr_pages, unsigned int gup_flags,
+		struct page **pages, struct vm_area_struct **vmas)
+{
+	return get_user_pages(start, nr_pages, gup_flags, pages, vmas);
+}
+#endif /* CONFIG_FS_DAX */
+
 int get_user_pages_fast(unsigned long start, int nr_pages, int write,
 			struct page **pages);