diff --git a/drivers/scsi/scsi_priv.h b/drivers/scsi/scsi_priv.h
index eff0059..3f34e93 100644
--- a/drivers/scsi/scsi_priv.h
+++ b/drivers/scsi/scsi_priv.h
@@ -74,6 +74,9 @@
 extern void scsi_free_queue(struct request_queue *q);
 extern int scsi_init_queue(void);
 extern void scsi_exit_queue(void);
+struct request_queue;
+struct request;
+extern int scsi_prep_fn(struct request_queue *, struct request *);
 
 /* scsi_proc.c */
 #ifdef CONFIG_SCSI_PROC_FS