diff --git a/include/linux/pagemap.h b/include/linux/pagemap.h
index b2bd2ba..a547d96 100644
--- a/include/linux/pagemap.h
+++ b/include/linux/pagemap.h
@@ -282,10 +282,16 @@
 	return ((loff_t)page->index) << PAGE_CACHE_SHIFT;
 }
 
+extern pgoff_t linear_hugepage_index(struct vm_area_struct *vma,
+				     unsigned long address);
+
 static inline pgoff_t linear_page_index(struct vm_area_struct *vma,
 					unsigned long address)
 {
-	pgoff_t pgoff = (address - vma->vm_start) >> PAGE_SHIFT;
+	pgoff_t pgoff;
+	if (unlikely(is_vm_hugetlb_page(vma)))
+		return linear_hugepage_index(vma, address);
+	pgoff = (address - vma->vm_start) >> PAGE_SHIFT;
 	pgoff += vma->vm_pgoff;
 	return pgoff >> (PAGE_CACHE_SHIFT - PAGE_SHIFT);
 }