3 files changed, 33 insertions, 8 deletions

diff --git a/mm/hugetlb.c b/mm/hugetlb.c
index e6afe527bd09..d143ab67be44 100644
--- a/mm/hugetlb.c
+++ b/mm/hugetlb.c
@@ -491,6 +491,8 @@ static void update_and_free_page(struct hstate *h, struct page *page)
 {
         int i;
 
+        VM_BUG_ON(h->order >= MAX_ORDER);
+
         h->nr_huge_pages--;
         h->nr_huge_pages_node[page_to_nid(page)]--;
         for (i = 0; i < pages_per_huge_page(h); i++) {
@@ -1005,6 +1007,14 @@ found:
         return 1;
 }
 
+static void prep_compound_huge_page(struct page *page, int order)
+{
+        if (unlikely(order > (MAX_ORDER - 1)))
+                prep_compound_gigantic_page(page, order);
+        else
+                prep_compound_page(page, order);
+}
+
 /* Put bootmem huge pages into the standard lists after mem_map is up */
 static void __init gather_bootmem_prealloc(void)
 {
@@ -1015,7 +1025,7 @@ static void __init gather_bootmem_prealloc(void)
                 struct hstate *h = m->hstate;
                 __ClearPageReserved(page);
                 WARN_ON(page_count(page) != 1);
-                prep_compound_page(page, h->order);
+                prep_compound_huge_page(page, h->order);
                 prep_new_huge_page(h, page, page_to_nid(page));
         }
 }
diff --git a/mm/internal.h b/mm/internal.h
index f482460de3e6..13333bc2eb68 100644
--- a/mm/internal.h
+++ b/mm/internal.h
@@ -17,6 +17,7 @@ void free_pgtables(struct mmu_gather *tlb, struct vm_area_struct *start_vma,
                 unsigned long floor, unsigned long ceiling);
 
 extern void prep_compound_page(struct page *page, unsigned long order);
+extern void prep_compound_gigantic_page(struct page *page, unsigned long order);
 
 static inline void set_page_count(struct page *page, int v)
 {
diff --git a/mm/page_alloc.c b/mm/page_alloc.c
index d0a240fbb8bf..54069e64e3a8 100644
--- 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)))