mm: handle initialising compound pages at orders greater than MAX_ORDER

[linux-2.6-omap-h63xx.git] / mm / page_alloc.c

diff --git a/mm/page_alloc.c b/mm/page_alloc.c
index e293c58bea58fc2195da7f34d95417262cedeffa..27b8681139fdb71e4d0da204ecc4a65fc3f7a1b5 100644 (file)
--- a/mm/page_alloc.c
+++ b/mm/page_alloc.c
@@ -268,13 +268,14 @@ void prep_compound_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++) {
-               struct page *p = page + i;
-
+       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);
                __SetPageTail(p);
                p->first_page = page;
        }
@@ -284,6 +285,7 @@ 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);
@@ -291,8 +293,9 @@ 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++) {
-               struct page *p = page + i;
+       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);
 
                if (unlikely(!PageTail(p) |
                                (p->first_page != page)))