vfio-ccw: Introduce new helper functions to free/destroy regions

Consolidate some of the cleanup code for the regions, so that
as more are added we reduce code duplication.
Signed-off-by: Farhan Ali <alifm@linux.ibm.com>
Signed-off-by: Eric Farman <farman@linux.ibm.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Message-Id: <20200505122745.53208-2-farman@linux.ibm.com>
Signed-off-by: Cornelia Huck <cohuck@redhat.com>

drivers/s390/cio/vfio_ccw_drv.c

@@ -116,6 +116,14 @@ static void vfio_ccw_sch_irq(struct subchannel *sch)
 	vfio_ccw_fsm_event(private, VFIO_CCW_EVENT_INTERRUPT);
 }
 
+static void vfio_ccw_free_regions(struct vfio_ccw_private *private)
+{
+	if (private->cmd_region)
+		kmem_cache_free(vfio_ccw_cmd_region, private->cmd_region);
+	if (private->io_region)
+		kmem_cache_free(vfio_ccw_io_region, private->io_region);
+}
+
 static int vfio_ccw_sch_probe(struct subchannel *sch)
 {
 	struct pmcw *pmcw = &sch->schib.pmcw;
@@ -181,10 +189,7 @@ static int vfio_ccw_sch_probe(struct subchannel *sch)
 	cio_disable_subchannel(sch);
 out_free:
 	dev_set_drvdata(&sch->dev, NULL);
-	if (private->cmd_region)
-		kmem_cache_free(vfio_ccw_cmd_region, private->cmd_region);
-	if (private->io_region)
-		kmem_cache_free(vfio_ccw_io_region, private->io_region);
+	vfio_ccw_free_regions(private);
 	kfree(private->cp.guest_cp);
 	kfree(private);
 	return ret;
@@ -200,8 +205,7 @@ static int vfio_ccw_sch_remove(struct subchannel *sch)
 
 	dev_set_drvdata(&sch->dev, NULL);
 
-	kmem_cache_free(vfio_ccw_cmd_region, private->cmd_region);
-	kmem_cache_free(vfio_ccw_io_region, private->io_region);
+	vfio_ccw_free_regions(private);
 	kfree(private->cp.guest_cp);
 	kfree(private);
 
@@ -304,6 +308,12 @@ static void vfio_ccw_debug_exit(void)
 	debug_unregister(vfio_ccw_debug_trace_id);
 }
 
+static void vfio_ccw_destroy_regions(void)
+{
+	kmem_cache_destroy(vfio_ccw_cmd_region);
+	kmem_cache_destroy(vfio_ccw_io_region);
+}
+
 static int __init vfio_ccw_sch_init(void)
 {
 	int ret;
@@ -346,8 +356,7 @@ static int __init vfio_ccw_sch_init(void)
 	return ret;
 
 out_err:
-	kmem_cache_destroy(vfio_ccw_cmd_region);
-	kmem_cache_destroy(vfio_ccw_io_region);
+	vfio_ccw_destroy_regions();
 	destroy_workqueue(vfio_ccw_work_q);
 	vfio_ccw_debug_exit();
 	return ret;
@@ -357,8 +366,7 @@ static void __exit vfio_ccw_sch_exit(void)
 {
 	css_driver_unregister(&vfio_ccw_sch_driver);
 	isc_unregister(VFIO_CCW_ISC);
-	kmem_cache_destroy(vfio_ccw_io_region);
-	kmem_cache_destroy(vfio_ccw_cmd_region);
+	vfio_ccw_destroy_regions();
 	destroy_workqueue(vfio_ccw_work_q);
 	vfio_ccw_debug_exit();
 }