diff --git a/dm-sflc/src/dev_vol.c b/dm-sflc/src/dev_vol.c
index 5bc3473..2195a73 100644
--- a/dm-sflc/src/dev_vol.c
+++ b/dm-sflc/src/dev_vol.c
@@ -21,8 +21,6 @@
  *  If not, see <https://www.gnu.org/licenses/>.
  */
 
-#include <linux/delay.h>
-
 #include "sflc.h"
 #include "legacy/sflc_legacy.h"
 
diff --git a/dm-sflc/src/sflc_types.h b/dm-sflc/src/sflc_types.h
index d2927cd..250178b 100644
--- a/dm-sflc/src/sflc_types.h
+++ b/dm-sflc/src/sflc_types.h
@@ -45,6 +45,8 @@
  * Type-checked polymorphism is achieved by having device and volume methods
  * take as argument a pointer to a base-class struct, instead of an opaque void
  * pointer. The pointer is then "down-cast" in the mode-specific method.
+ * The same pattern is followed for the struct representing the constructor
+ * arguments.
  */
 
 #ifndef _SFLC_TYPES_H
@@ -116,6 +118,25 @@ struct sflc_volume_base
 	struct sflc_mode_ops	*ops;
 };
 
+/**
+ * Base class for constructor arguments.
+ * Inherited by derived classes for mode-specific arguments.
+ */
+struct sflc_ctor_args_base
+{
+	/* Shufflecake mode: Legacy or Lite */
+	u32	mode;
+
+	/*Shufflecake-unique device ID*/
+	u32	dev_id;
+
+	/* Underlying block device: MAJOR,MINOR */
+	dev_t	bdev_devt;
+
+	/* Volume index within the device */
+	u32	vol_idx;
+};
+
 
 /*
  *----------------------------
@@ -125,14 +146,14 @@ struct sflc_volume_base
 
 /* Device constructor */
 typedef struct sflc_device_base* (*sflc_mode_dev_ctr_fn) (
-		struct dm_target *ti, int argc, char **argv);
+		struct dm_target *ti, struct sflc_ctor_args_base *args_base);
 /* Device destructor */
 typedef void (*sflc_mode_dev_dtr_fn) (struct sflc_device_base* sd_base);
 
 /* Volume constructor */
 typedef struct sflc_volume_base* (*sflc_mode_vol_ctr_fn) (
 		struct sflc_device_base *sd_base, struct dm_target *ti,
-		int argc, char **argv);
+		struct sflc_ctor_args_base *args_base);
 /* Volume destructor */
 typedef void (*sflc_mode_vol_dtr_fn) (struct sflc_volume_base* sv_base);