diff --git a/tools/testing/selftests/filesystems/incfs/utils.c b/tools/testing/selftests/filesystems/incfs/utils.c
index 0411d912ae05..d7deb5321c3e 100644
--- a/tools/testing/selftests/filesystems/incfs/utils.c
+++ b/tools/testing/selftests/filesystems/incfs/utils.c
@@ -81,6 +81,16 @@ int mount_fs(const char *mount_dir, const char *backing_dir,
 	return result;
 }
 
+int umount_fs(const char *mount_dir)
+{
+	int result;
+
+	result = umount(mount_dir);
+	if (result != 0)
+		perror("Error unmounting fs.");
+	return result;
+}
+
 int mount_fs_opt(const char *mount_dir, const char *backing_dir,
 		 const char *opt, bool remount)
 {
diff --git a/tools/testing/selftests/filesystems/incfs/utils.h b/tools/testing/selftests/filesystems/incfs/utils.h
index f5ed8dc5f0ff..17a1ac5eef7d 100644
--- a/tools/testing/selftests/filesystems/incfs/utils.h
+++ b/tools/testing/selftests/filesystems/incfs/utils.h
@@ -29,6 +29,8 @@ int drop_caches(void);
 int mount_fs(const char *mount_dir, const char *backing_dir,
 	     int read_timeout_ms);
 
+int umount_fs(const char *mount_dir);
+
 int mount_fs_opt(const char *mount_dir, const char *backing_dir,
 		 const char *opt, bool remount);