[SCSI] zfcp: Implement module unloading

With the reference counting for zfcp data structures, it is now
possible to implement module unloading again. Module unloading
requires to free all data structures in the module exit function. This
is done by unregistering zfcp from s390 cio and the SCSI midlayer
first in the module exit function.

Reviewed-by: Swen Schillig <swen@vnet.ibm.com>
Signed-off-by: Christof Schmitt <christof.schmitt@de.ibm.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
diff --git a/drivers/s390/scsi/zfcp_aux.c b/drivers/s390/scsi/zfcp_aux.c
index baef2ec..12de1ce 100644
--- a/drivers/s390/scsi/zfcp_aux.c
+++ b/drivers/s390/scsi/zfcp_aux.c
@@ -189,7 +189,7 @@
 		goto out_misc;
 	}
 
-	retval = zfcp_ccw_register();
+	retval = ccw_driver_register(&zfcp_ccw_driver);
 	if (retval) {
 		pr_err("The zfcp device driver could not register with "
 		       "the common I/O layer\n");
@@ -218,6 +218,19 @@
 
 module_init(zfcp_module_init);
 
+static void __exit zfcp_module_exit(void)
+{
+	ccw_driver_unregister(&zfcp_ccw_driver);
+	misc_deregister(&zfcp_cfdc_misc);
+	fc_release_transport(zfcp_data.scsi_transport_template);
+	kmem_cache_destroy(zfcp_data.gid_pn_cache);
+	kmem_cache_destroy(zfcp_data.sr_buffer_cache);
+	kmem_cache_destroy(zfcp_data.qtcb_cache);
+	kmem_cache_destroy(zfcp_data.gpn_ft_cache);
+}
+
+module_exit(zfcp_module_exit);
+
 /**
  * zfcp_get_unit_by_lun - find unit in unit list of port by FCP LUN
  * @port: pointer to port to search for unit