Merge branch 'akpm' (fixes from Andrew)

Merge patches from Andrew Morton:
 "13 fixes"

* emailed patches from Andrew Morton <akpm@linux-foundation.org>:
  mm: place page->pmd_huge_pte to right union
  MAINTAINERS: add keyboard driver to Hyper-V file list
  x86, mm: do not leak page->ptl for pmd page tables
  ipc,shm: correct error return value in shmctl (SHM_UNLOCK)
  mm, mempolicy: silence gcc warning
  block/partitions/efi.c: fix bound check
  ARM: drivers/rtc/rtc-at91rm9200.c: disable interrupts at shutdown
  mm: hugetlbfs: fix hugetlbfs optimization
  kernel: remove CONFIG_USE_GENERIC_SMP_HELPERS cleanly
  ipc,shm: fix shm_file deletion races
  mm: thp: give transparent hugepage code a separate copy_page
  checkpatch: fix "Use of uninitialized value" warnings
  configfs: fix race between dentry put and lookup

1 files changed, 17 insertions, 34 deletions

diff --git a/mm/hugetlb.c b/mm/hugetlb.c
index 7d57af21f49e..dee6cf4e6d34 100644
--- a/mm/hugetlb.c
+++ b/mm/hugetlb.c
@@ -476,40 +476,6 @@ static int vma_has_reserves(struct vm_area_struct *vma, long chg)
 	return 0;
 }
 
-static void copy_gigantic_page(struct page *dst, struct page *src)
-{
-	int i;
-	struct hstate *h = page_hstate(src);
-	struct page *dst_base = dst;
-	struct page *src_base = src;
-
-	for (i = 0; i < pages_per_huge_page(h); ) {
-		cond_resched();
-		copy_highpage(dst, src);
-
-		i++;
-		dst = mem_map_next(dst, dst_base, i);
-		src = mem_map_next(src, src_base, i);
-	}
-}
-
-void copy_huge_page(struct page *dst, struct page *src)
-{
-	int i;
-	struct hstate *h = page_hstate(src);
-
-	if (unlikely(pages_per_huge_page(h) > MAX_ORDER_NR_PAGES)) {
-		copy_gigantic_page(dst, src);
-		return;
-	}
-
-	might_sleep();
-	for (i = 0; i < pages_per_huge_page(h); i++) {
-		cond_resched();
-		copy_highpage(dst + i, src + i);
-	}
-}
-
 static void enqueue_huge_page(struct hstate *h, struct page *page)
 {
 	int nid = page_to_nid(page);
@@ -736,6 +702,23 @@ int PageHuge(struct page *page)
 }
 EXPORT_SYMBOL_GPL(PageHuge);
 
+/*
+ * PageHeadHuge() only returns true for hugetlbfs head page, but not for
+ * normal or transparent huge pages.
+ */
+int PageHeadHuge(struct page *page_head)
+{
+	compound_page_dtor *dtor;
+
+	if (!PageHead(page_head))
+		return 0;
+
+	dtor = get_compound_page_dtor(page_head);
+
+	return dtor == free_huge_page;
+}
+EXPORT_SYMBOL_GPL(PageHeadHuge);
+
 pgoff_t __basepage_index(struct page *page)
 {
 	struct page *page_head = compound_head(page);