1 files changed, 16 insertions, 0 deletions

diff --git a/mm/hugetlb.c b/mm/hugetlb.c
index 6058b53dcb89..5cb8bc7c80f7 100644
--- a/mm/hugetlb.c
+++ b/mm/hugetlb.c
@@ -220,6 +220,22 @@ static pgoff_t vma_hugecache_offset(struct hstate *h,
 }
 
 /*
+ * Return the size of the pages allocated when backing a VMA. In the majority
+ * cases this will be same size as used by the page table entries.
+ */
+unsigned long vma_kernel_pagesize(struct vm_area_struct *vma)
+{
+        struct hstate *hstate;
+
+        if (!is_vm_hugetlb_page(vma))
+                return PAGE_SIZE;
+
+        hstate = hstate_vma(vma);
+
+        return 1UL << (hstate->order + PAGE_SHIFT);
+}
+
+/*
  * Flags for MAP_PRIVATE reservations.  These are stored in the bottom
  * bits of the reservation map pointer, which are always clear due to
  * alignment.