scsi: qla2xxx: Unregister chrdev if module initialization fails

BugLink: https://bugs.launchpad.net/bugs/1864773

[ Upstream commit c794d24e ]

If module initialization fails after the character device has been
registered, unregister the character device. Additionally, avoid
duplicating error path code.

Cc: Himanshu Madhani <hmadhani@marvell.com>
Cc: Giridhar Malavali <giridhar.malavali@qlogic.com>
Fixes: 6a03b4cd ("[SCSI] qla2xxx: Add char device to increase driver use count") # v2.6.35.
Signed-off-by: Bart Van Assche <bvanassche@acm.org>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Signed-off-by: Khalid Elmously <khalid.elmously@canonical.com>
Signed-off-by: Kleber Sacilotto de Souza <kleber.souza@canonical.com>

drivers/scsi/qla2xxx/qla_os.c

@@ -5939,8 +5939,7 @@ qla2x00_module_init(void)
 	/* Initialize target kmem_cache and mem_pools */
 	ret = qlt_init();
 	if (ret < 0) {
-		kmem_cache_destroy(srb_cachep);
-		return ret;
+		goto destroy_cache;
 	} else if (ret > 0) {
 		/*
 		 * If initiator mode is explictly disabled by qlt_init(),
@@ -5959,11 +5958,10 @@ qla2x00_module_init(void)
 	qla2xxx_transport_template =
 	    fc_attach_transport(&qla2xxx_transport_functions);
 	if (!qla2xxx_transport_template) {
-		kmem_cache_destroy(srb_cachep);
 		ql_log(ql_log_fatal, NULL, 0x0002,
 		    "fc_attach_transport failed...Failing load!.\n");
-		qlt_exit();
-		return -ENODEV;
+		ret = -ENODEV;
+		goto qlt_exit;
 	}
 
 	apidev_major = register_chrdev(0, QLA2XXX_APIDEV, &apidev_fops);
@@ -5975,27 +5973,37 @@ qla2x00_module_init(void)
 	qla2xxx_transport_vport_template =
 	    fc_attach_transport(&qla2xxx_transport_vport_functions);
 	if (!qla2xxx_transport_vport_template) {
-		kmem_cache_destroy(srb_cachep);
-		qlt_exit();
-		fc_release_transport(qla2xxx_transport_template);
 		ql_log(ql_log_fatal, NULL, 0x0004,
 		    "fc_attach_transport vport failed...Failing load!.\n");
-		return -ENODEV;
+		ret = -ENODEV;
+		goto unreg_chrdev;
 	}
 	ql_log(ql_log_info, NULL, 0x0005,
 	    "QLogic Fibre Channel HBA Driver: %s.\n",
 	    qla2x00_version_str);
 	ret = pci_register_driver(&qla2xxx_pci_driver);
 	if (ret) {
-		kmem_cache_destroy(srb_cachep);
-		qlt_exit();
-		fc_release_transport(qla2xxx_transport_template);
-		fc_release_transport(qla2xxx_transport_vport_template);
 		ql_log(ql_log_fatal, NULL, 0x0006,
 		    "pci_register_driver failed...ret=%d Failing load!.\n",
 		    ret);
+		goto release_vport_transport;
 	}
 	return ret;
+
+release_vport_transport:
+	fc_release_transport(qla2xxx_transport_vport_template);
+
+unreg_chrdev:
+	if (apidev_major >= 0)
+		unregister_chrdev(apidev_major, QLA2XXX_APIDEV);
+	fc_release_transport(qla2xxx_transport_template);
+
+qlt_exit:
+	qlt_exit();
+
+destroy_cache:
+	kmem_cache_destroy(srb_cachep);
+	return ret;
 }
 
 /**