diff --git a/sys/dev/aic7xxx/aic79xx_osm.c b/sys/dev/aic7xxx/aic79xx_osm.c
--- a/sys/dev/aic7xxx/aic79xx_osm.c
+++ b/sys/dev/aic7xxx/aic79xx_osm.c
@@ -303,6 +303,25 @@
 	ahd_unlock(ahd);
 }
 
+static void
+ahd_sync_ccb(struct ahd_softc *ahd, struct scb *scb, union ccb *ccb, bool post)
+{
+	bus_dmasync_op_t op;
+	uint32_t rdmask;
+
+	if (ccb->ccb_h.func_code == XPT_CONT_TARGET_IO)
+		rdmask = CAM_DIR_OUT;
+	else
+		rdmask = CAM_DIR_IN;
+
+	if ((ccb->ccb_h.flags & CAM_DIR_MASK) == rdmask)
+		op = post ? BUS_DMASYNC_POSTREAD : BUS_DMASYNC_PREREAD;
+	else
+		op = post ? BUS_DMASYNC_POSTWRITE : BUS_DMASYNC_PREWRITE;
+
+	bus_dmamap_sync(ahd->buffer_dmat, scb->dmamap, op);
+}
+
 /*
  * We have an scb which has been processed by the
  * adaptor, now we look to see how the operation
@@ -324,13 +343,7 @@
 	callout_stop(&scb->io_timer);
 
 	if ((ccb->ccb_h.flags & CAM_DIR_MASK) != CAM_DIR_NONE) {
-		bus_dmasync_op_t op;
-
-		if ((ccb->ccb_h.flags & CAM_DIR_MASK) == CAM_DIR_IN)
-			op = BUS_DMASYNC_POSTREAD;
-		else
-			op = BUS_DMASYNC_POSTWRITE;
-		bus_dmamap_sync(ahd->buffer_dmat, scb->dmamap, op);
+		ahd_sync_ccb(ahd, scb, ccb, true);
 		bus_dmamap_unload(ahd->buffer_dmat, scb->dmamap);
 	}
 
@@ -961,7 +974,6 @@
 	scb->sg_count = 0;
 	if (nsegments != 0) {
 		void *sg;
-		bus_dmasync_op_t op;
 		u_int i;
 
 		/* Copy the segments into our SG list */
@@ -971,13 +983,8 @@
 					  /*last*/i == 1);
 			dm_segs++;
 		}
-		
-		if ((ccb->ccb_h.flags & CAM_DIR_MASK) == CAM_DIR_IN)
-			op = BUS_DMASYNC_PREREAD;
-		else
-			op = BUS_DMASYNC_PREWRITE;
 
-		bus_dmamap_sync(ahd->buffer_dmat, scb->dmamap, op);
+		ahd_sync_ccb(ahd, scb, ccb, false);
 
 		if (ccb->ccb_h.func_code == XPT_CONT_TARGET_IO) {
 			struct target_data *tdata;
diff --git a/sys/dev/aic7xxx/aic7xxx_osm.c b/sys/dev/aic7xxx/aic7xxx_osm.c
--- a/sys/dev/aic7xxx/aic7xxx_osm.c
+++ b/sys/dev/aic7xxx/aic7xxx_osm.c
@@ -302,6 +302,25 @@
 	ahc_unlock(ahc);
 }
 
+static void
+ahc_sync_ccb(struct ahc_softc *ahc, struct scb *scb, union ccb *ccb, bool post)
+{
+	bus_dmasync_op_t op;
+	uint32_t rdmask;
+
+	if (ccb->ccb_h.func_code == XPT_CONT_TARGET_IO)
+		rdmask = CAM_DIR_OUT;
+	else
+		rdmask = CAM_DIR_IN;
+
+	if ((ccb->ccb_h.flags & CAM_DIR_MASK) == rdmask)
+		op = post ? BUS_DMASYNC_POSTREAD : BUS_DMASYNC_PREREAD;
+	else
+		op = post ? BUS_DMASYNC_POSTWRITE : BUS_DMASYNC_PREWRITE;
+
+	bus_dmamap_sync(ahc->buffer_dmat, scb->dmamap, op);
+}
+
 /*
  * We have an scb which has been processed by the
  * adaptor, now we look to see how the operation
@@ -333,13 +352,7 @@
 	callout_stop(&scb->io_timer);
 
 	if ((ccb->ccb_h.flags & CAM_DIR_MASK) != CAM_DIR_NONE) {
-		bus_dmasync_op_t op;
-
-		if ((ccb->ccb_h.flags & CAM_DIR_MASK) == CAM_DIR_IN)
-			op = BUS_DMASYNC_POSTREAD;
-		else
-			op = BUS_DMASYNC_POSTWRITE;
-		bus_dmamap_sync(ahc->buffer_dmat, scb->dmamap, op);
+		ahc_sync_ccb(ahc, scb, ccb, true);
 		bus_dmamap_unload(ahc->buffer_dmat, scb->dmamap);
 	}
 
@@ -943,7 +956,6 @@
 	if (nsegments != 0) {
 		struct	  ahc_dma_seg *sg;
 		bus_dma_segment_t *end_seg;
-		bus_dmasync_op_t op;
 
 		end_seg = dm_segs + nsegments;
 
@@ -968,12 +980,7 @@
 		 */
 		scb->hscb->sgptr = aic_htole32(scb->sg_list_phys|SG_FULL_RESID);
 
-		if ((ccb->ccb_h.flags & CAM_DIR_MASK) == CAM_DIR_IN)
-			op = BUS_DMASYNC_PREREAD;
-		else
-			op = BUS_DMASYNC_PREWRITE;
-
-		bus_dmamap_sync(ahc->buffer_dmat, scb->dmamap, op);
+		ahc_sync_ccb(ahc, scb, ccb, false);
 
 		if (ccb->ccb_h.func_code == XPT_CONT_TARGET_IO) {
 			struct target_data *tdata;