Merge branch 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/linville/wirel...

[pandora-kernel.git] / arch / powerpc / mm / gup.c

diff --git a/arch/powerpc/mm/gup.c b/arch/powerpc/mm/gup.c
index d7efdbf..fec1320 100644 (file)
--- a/arch/powerpc/mm/gup.c
+++ b/arch/powerpc/mm/gup.c
@@ -16,6 +16,16 @@
 
 #ifdef __HAVE_ARCH_PTE_SPECIAL
 
+static inline void get_huge_page_tail(struct page *page)
+{
+       /*
+        * __split_huge_page_refcount() cannot run
+        * from under us.
+        */
+       VM_BUG_ON(atomic_read(&page->_count) < 0);
+       atomic_inc(&page->_count);
+}
+
 /*
  * The performance critical leaf functions are made noinline otherwise gcc
  * inlines everything into a single function which results in too much
@@ -47,6 +57,8 @@ static noinline int gup_pte_range(pmd_t pmd, unsigned long addr,
                        put_page(page);
                        return 0;
                }
+               if (PageTail(page))
+                       get_huge_page_tail(page);
                pages[*nr] = page;
                (*nr)++;