#define BUFFER_TRACE2(bh, bh2, info) do {} while (0)
#define JBUFFER_TRACE(jh, info) do {} while (0)
+/*
+ * jbd2_dev_to_name is a utility function used by the jbd2 and ext4
+ * tracing infrastructure to map a dev_t to a device name.
+ */
+extern const char *jbd2_dev_to_name(dev_t device);
+
#endif /* __KERNEL__ */
#endif /* _LINUX_JBD2_H */