hugetlb: pull gigantic page initialisation out of the default path

[safe/jmp/linux-2.6] / mm / page_alloc.c

diff --git a/mm/page_alloc.c b/mm/page_alloc.c
index d0a240f..54069e6 100644 (file)
--- a/mm/page_alloc.c
+++ b/mm/page_alloc.c
@@ -263,24 +263,39 @@ void prep_compound_page(struct page *page, unsigned long order)
 {
        int i;
        int nr_pages = 1 << order;
+
+       set_compound_page_dtor(page, free_compound_page);
+       set_compound_order(page, order);
+       __SetPageHead(page);
+       for (i = 1; i < nr_pages; i++) {
+               struct page *p = page + i;
+
+               __SetPageTail(p);
+               p->first_page = page;
+       }
+}
+
+#ifdef CONFIG_HUGETLBFS
+void prep_compound_gigantic_page(struct page *page, unsigned long order)
+{
+       int i;
+       int nr_pages = 1 << order;
        struct page *p = page + 1;
 
        set_compound_page_dtor(page, free_compound_page);
        set_compound_order(page, order);
        __SetPageHead(page);
-       for (i = 1; i < nr_pages; i++, p++) {
-               if (unlikely((i & (MAX_ORDER_NR_PAGES - 1)) == 0))
-                       p = pfn_to_page(page_to_pfn(page) + i);
+       for (i = 1; i < nr_pages; i++, p = mem_map_next(p, page, i)) {
                __SetPageTail(p);
                p->first_page = page;
        }
 }
+#endif
 
 static void destroy_compound_page(struct page *page, unsigned long order)
 {
        int i;
        int nr_pages = 1 << order;
-       struct page *p = page + 1;
 
        if (unlikely(compound_order(page) != order))
                bad_page(page);
@@ -288,9 +303,8 @@ static void destroy_compound_page(struct page *page, unsigned long order)
        if (unlikely(!PageHead(page)))
                        bad_page(page);
        __ClearPageHead(page);
-       for (i = 1; i < nr_pages; i++, p++) {
-               if (unlikely((i & (MAX_ORDER_NR_PAGES - 1)) == 0))
-                       p = pfn_to_page(page_to_pfn(page) + i);
+       for (i = 1; i < nr_pages; i++) {
+               struct page *p = page + i;
 
                if (unlikely(!PageTail(p) |
                                (p->first_page != page)))