diff --git a/mm/gup.c b/mm/gup.c
index a7efb027d6cf..614b8536b3b6 100644
--- a/mm/gup.c
+++ b/mm/gup.c

@@ -1691,6 +1691,69 @@ size_t fault_in_writeable(char __user *uaddr, size_t size)
 }
 EXPORT_SYMBOL(fault_in_writeable);
 
+/*
+ * fault_in_safe_writeable - fault in an address range for writing
+ * @uaddr: start of address range
+ * @size: length of address range
+ *
+ * Faults in an address range using get_user_pages, i.e., without triggering
+ * hardware page faults.  This is primarily useful when we already know that
+ * some or all of the pages in the address range aren't in memory.
+ *
+ * Other than fault_in_writeable(), this function is non-destructive.
+ *
+ * Note that we don't pin or otherwise hold the pages referenced that we fault
+ * in.  There's no guarantee that they'll stay in memory for any duration of
+ * time.
+ *
+ * Returns the number of bytes not faulted in, like copy_to_user() and
+ * copy_from_user().
+ */
+size_t fault_in_safe_writeable(const char __user *uaddr, size_t size)
+{
+	unsigned long start = (unsigned long)uaddr;
+	unsigned long end, nstart, nend;
+	struct mm_struct *mm = current->mm;
+	struct vm_area_struct *vma = NULL;