diff --git a/include/linux/hugetlb.h b/include/linux/hugetlb.h
index aaf3d472e6b5..9c098a02a09e 100644
--- a/include/linux/hugetlb.h
+++ b/include/linux/hugetlb.h
@@ -792,6 +792,23 @@ static inline unsigned huge_page_shift(struct hstate *h)
 	return h->order + PAGE_SHIFT;
 }
 
+/**
+ * hugetlb_linear_page_index() - linear_page_index() but in hugetlb
+ *				 page size granularity.
+ * @vma: the hugetlb VMA
+ * @address: the virtual address within the VMA
+ *
+ * Return: the page offset within the mapping in huge page units.
+ */
+static inline pgoff_t hugetlb_linear_page_index(struct vm_area_struct *vma,
+		unsigned long address)
+{
+	struct hstate *h = hstate_vma(vma);
+
+	return ((address - vma->vm_start) >> huge_page_shift(h)) +
+		(vma->vm_pgoff >> huge_page_order(h));
+}
+
 static inline bool order_is_gigantic(unsigned int order)
 {
 	return order > MAX_PAGE_ORDER;
diff --git a/mm/userfaultfd.c b/mm/userfaultfd.c
index e19872e51878..2c565c7134b6 100644
--- a/mm/userfaultfd.c
+++ b/mm/userfaultfd.c
@@ -573,7 +573,7 @@ static __always_inline ssize_t mfill_atomic_hugetlb(
 		 * in the case of shared pmds.  fault mutex prevents
 		 * races with other faulting threads.
 		 */
-		idx = linear_page_index(dst_vma, dst_addr);
+		idx = hugetlb_linear_page_index(dst_vma, dst_addr);
 		mapping = dst_vma->vm_file->f_mapping;
 		hash = hugetlb_fault_mutex_hash(mapping, idx);
 		mutex_lock(&hugetlb_fault_mutex_table[hash]);