mm/hugetlb.c: defer PageHeadHuge() symbol export

[karo-tx-linux.git] / mm / hugetlb.c

diff --git a/mm/hugetlb.c b/mm/hugetlb.c
index 7d57af21f49e920776979dfe11023780ebff6afb..f730b7a375904fd9e6915d7b562657ea819bf5cf 100644 (file)
--- 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);
@@ -724,18 +690,26 @@ static void prep_compound_gigantic_page(struct page *page, unsigned long order)
  */
 int PageHuge(struct page *page)
 {
-       compound_page_dtor *dtor;
-
        if (!PageCompound(page))
                return 0;
 
        page = compound_head(page);
-       dtor = get_compound_page_dtor(page);
-
-       return dtor == free_huge_page;
+       return get_compound_page_dtor(page) == free_huge_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)
+{
+       if (!PageHead(page_head))
+               return 0;
+
+       return get_compound_page_dtor(page_head) == free_huge_page;
+}
+
 pgoff_t __basepage_index(struct page *page)
 {
        struct page *page_head = compound_head(page);
@@ -3096,7 +3070,7 @@ long follow_hugetlb_page(struct mm_struct *mm, struct vm_area_struct *vma,
 same_page:
                if (pages) {
                        pages[i] = mem_map_offset(page, pfn_offset);
-                       get_page(pages[i]);
+                       get_page_foll(pages[i]);
                }
 
                if (vmas)