1 files changed, 23 insertions, 5 deletions

diff --git a/include/linux/huge_mm.h b/include/linux/huge_mm.h
index 1b921299abc4..c8af7a2efb52 100644
--- a/include/linux/huge_mm.h
+++ b/include/linux/huge_mm.h
@@ -51,6 +51,9 @@ extern pmd_t *page_check_address_pmd(struct page *page,
                                      unsigned long address,
                                      enum page_check_address_pmd_flag flag);
 
+#define HPAGE_PMD_ORDER (HPAGE_PMD_SHIFT-PAGE_SHIFT)
+#define HPAGE_PMD_NR (1<<HPAGE_PMD_ORDER)
+
 #ifdef CONFIG_TRANSPARENT_HUGEPAGE
 #define HPAGE_PMD_SHIFT HPAGE_SHIFT
 #define HPAGE_PMD_MASK HPAGE_MASK
@@ -102,8 +105,6 @@ extern void __split_huge_page_pmd(struct mm_struct *mm, pmd_t *pmd);
                 BUG_ON(pmd_trans_splitting(*____pmd) ||                 \
                        pmd_trans_huge(*____pmd));                       \
         } while (0)
-#define HPAGE_PMD_ORDER (HPAGE_PMD_SHIFT-PAGE_SHIFT)
-#define HPAGE_PMD_NR (1<<HPAGE_PMD_ORDER)
 #if HPAGE_PMD_ORDER > MAX_ORDER
 #error "hugepages can't be allocated by the buddy allocator"
 #endif
@@ -113,6 +114,18 @@ extern void __vma_adjust_trans_huge(struct vm_area_struct *vma,
                                     unsigned long start,
                                     unsigned long end,
                                     long adjust_next);
+extern int __pmd_trans_huge_lock(pmd_t *pmd,
+                                 struct vm_area_struct *vma);
+/* mmap_sem must be held on entry */
+static inline int pmd_trans_huge_lock(pmd_t *pmd,
+                                      struct vm_area_struct *vma)
+{
+        VM_BUG_ON(!rwsem_is_locked(&vma->vm_mm->mmap_sem));
+        if (pmd_trans_huge(*pmd))
+                return __pmd_trans_huge_lock(pmd, vma);
+        else
+                return 0;
+}
 static inline void vma_adjust_trans_huge(struct vm_area_struct *vma,
                                          unsigned long start,
                                          unsigned long end,
@@ -146,9 +159,9 @@ static inline struct page *compound_trans_head(struct page *page)
         return page;
 }
 #else /* CONFIG_TRANSPARENT_HUGEPAGE */
-#define HPAGE_PMD_SHIFT ({ BUG(); 0; })
-#define HPAGE_PMD_MASK ({ BUG(); 0; })
-#define HPAGE_PMD_SIZE ({ BUG(); 0; })
+#define HPAGE_PMD_SHIFT ({ BUILD_BUG(); 0; })
+#define HPAGE_PMD_MASK ({ BUILD_BUG(); 0; })
+#define HPAGE_PMD_SIZE ({ BUILD_BUG(); 0; })
 
 #define hpage_nr_pages(x) 1
 
@@ -176,6 +189,11 @@ static inline void vma_adjust_trans_huge(struct vm_area_struct *vma,
                                          long adjust_next)
 {
 }
+static inline int pmd_trans_huge_lock(pmd_t *pmd,
+                                      struct vm_area_struct *vma)
+{
+        return 0;
+}
 #endif /* CONFIG_TRANSPARENT_HUGEPAGE */
 
 #endif /* _LINUX_HUGE_MM_H */