scsi: zfcp: use enum zfcp_erp_act_result for argument/return of affected functions

With that instead of just "int" it becomes clear which functions return
this type and which ones also accept it as argument they just pass through
in some cases or modify in other cases.  v2.6.27 commit 287ac01acf22
("[SCSI] zfcp: Cleanup code in zfcp_erp.c") introduced the enum which was
cpp defines previously.

Silence some false -Wswitch compiler warning cases with individual
NOP cases. When adding more enum values and building with W=1 we
would get compiler warnings about missed new cases.

Consistently use the variable name "result", so change "retval" in
zfcp_erp_strategy() to "result". This avoids confusion with other compile
unit variables "retval" having different semantics and type.

Signed-off-by: Steffen Maier <maier@linux.ibm.com>
Reviewed-by: Benjamin Block <bblock@linux.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

1 files changed, 84 insertions, 40 deletions

diff --git a/drivers/s390/scsi/zfcp_erp.c b/drivers/s390/scsi/zfcp_erp.c
index 3da870e55ab5..5c7fb64111fe 100644
--- a/drivers/s390/scsi/zfcp_erp.c
+++ b/drivers/s390/scsi/zfcp_erp.c
@@ -713,7 +713,8 @@ static void zfcp_erp_enqueue_ptp_port(struct zfcp_adapter *adapter)
 	_zfcp_erp_port_reopen(port, 0, "ereptp1");
 }
 
-static int zfcp_erp_adapter_strat_fsf_xconf(struct zfcp_erp_action *erp_action)
+static enum zfcp_erp_act_result zfcp_erp_adapter_strat_fsf_xconf(
+	struct zfcp_erp_action *erp_action)
 {
 	int retries;
 	int sleep = 1;
@@ -758,7 +759,8 @@ static int zfcp_erp_adapter_strat_fsf_xconf(struct zfcp_erp_action *erp_action)
 	return ZFCP_ERP_SUCCEEDED;
 }
 
-static int zfcp_erp_adapter_strategy_open_fsf_xport(struct zfcp_erp_action *act)
+static enum zfcp_erp_act_result zfcp_erp_adapter_strategy_open_fsf_xport(
+	struct zfcp_erp_action *act)
 {
 	int ret;
 	struct zfcp_adapter *adapter = act->adapter;
@@ -783,7 +785,8 @@ static int zfcp_erp_adapter_strategy_open_fsf_xport(struct zfcp_erp_action *act)
 	return ZFCP_ERP_SUCCEEDED;
 }
 
-static int zfcp_erp_adapter_strategy_open_fsf(struct zfcp_erp_action *act)
+static enum zfcp_erp_act_result zfcp_erp_adapter_strategy_open_fsf(
+	struct zfcp_erp_action *act)
 {
 	if (zfcp_erp_adapter_strat_fsf_xconf(act) == ZFCP_ERP_FAILED)
 		return ZFCP_ERP_FAILED;
@@ -822,7 +825,8 @@ static void zfcp_erp_adapter_strategy_close(struct zfcp_erp_action *act)
 			  ZFCP_STATUS_ADAPTER_LINK_UNPLUGGED, &adapter->status);
 }
 
-static int zfcp_erp_adapter_strategy_open(struct zfcp_erp_action *act)
+static enum zfcp_erp_act_result zfcp_erp_adapter_strategy_open(
+	struct zfcp_erp_action *act)
 {
 	struct zfcp_adapter *adapter = act->adapter;
 
@@ -843,7 +847,8 @@ static int zfcp_erp_adapter_strategy_open(struct zfcp_erp_action *act)
 	return ZFCP_ERP_SUCCEEDED;
 }
 
-static int zfcp_erp_adapter_strategy(struct zfcp_erp_action *act)
+static enum zfcp_erp_act_result zfcp_erp_adapter_strategy(
+	struct zfcp_erp_action *act)
 {
 	struct zfcp_adapter *adapter = act->adapter;
 
@@ -861,7 +866,8 @@ static int zfcp_erp_adapter_strategy(struct zfcp_erp_action *act)
 	return ZFCP_ERP_SUCCEEDED;
 }
 
-static int zfcp_erp_port_forced_strategy_close(struct zfcp_erp_action *act)
+static enum zfcp_erp_act_result zfcp_erp_port_forced_strategy_close(
+	struct zfcp_erp_action *act)
 {
 	int retval;
 
@@ -875,7 +881,8 @@ static int zfcp_erp_port_forced_strategy_close(struct zfcp_erp_action *act)
 	return ZFCP_ERP_CONTINUES;
 }
 
-static int zfcp_erp_port_forced_strategy(struct zfcp_erp_action *erp_action)
+static enum zfcp_erp_act_result zfcp_erp_port_forced_strategy(
+	struct zfcp_erp_action *erp_action)
 {
 	struct zfcp_port *port = erp_action->port;
 	int status = atomic_read(&port->status);
@@ -902,7 +909,8 @@ static int zfcp_erp_port_forced_strategy(struct zfcp_erp_action *erp_action)
 	return ZFCP_ERP_FAILED;
 }
 
-static int zfcp_erp_port_strategy_close(struct zfcp_erp_action *erp_action)
+static enum zfcp_erp_act_result zfcp_erp_port_strategy_close(
+	struct zfcp_erp_action *erp_action)
 {
 	int retval;
 
@@ -915,7 +923,8 @@ static int zfcp_erp_port_strategy_close(struct zfcp_erp_action *erp_action)
 	return ZFCP_ERP_CONTINUES;
 }
 
-static int zfcp_erp_port_strategy_open_port(struct zfcp_erp_action *erp_action)
+static enum zfcp_erp_act_result zfcp_erp_port_strategy_open_port(
+	struct zfcp_erp_action *erp_action)
 {
 	int retval;
 
@@ -941,7 +950,8 @@ static int zfcp_erp_open_ptp_port(struct zfcp_erp_action *act)
 	return zfcp_erp_port_strategy_open_port(act);
 }
 
-static int zfcp_erp_port_strategy_open_common(struct zfcp_erp_action *act)
+static enum zfcp_erp_act_result zfcp_erp_port_strategy_open_common(
+	struct zfcp_erp_action *act)
 {
 	struct zfcp_adapter *adapter = act->adapter;
 	struct zfcp_port *port = act->port;
@@ -982,7 +992,8 @@ static int zfcp_erp_port_strategy_open_common(struct zfcp_erp_action *act)
 	return ZFCP_ERP_FAILED;
 }
 
-static int zfcp_erp_port_strategy(struct zfcp_erp_action *erp_action)
+static enum zfcp_erp_act_result zfcp_erp_port_strategy(
+	struct zfcp_erp_action *erp_action)
 {
 	struct zfcp_port *port = erp_action->port;
 	int p_status = atomic_read(&port->status);
@@ -1024,7 +1035,8 @@ static void zfcp_erp_lun_strategy_clearstati(struct scsi_device *sdev)
 			  &zfcp_sdev->status);
 }
 
-static int zfcp_erp_lun_strategy_close(struct zfcp_erp_action *erp_action)
+static enum zfcp_erp_act_result zfcp_erp_lun_strategy_close(
+	struct zfcp_erp_action *erp_action)
 {
 	int retval = zfcp_fsf_close_lun(erp_action);
 	if (retval == -ENOMEM)
@@ -1035,7 +1047,8 @@ static int zfcp_erp_lun_strategy_close(struct zfcp_erp_action *erp_action)
 	return ZFCP_ERP_CONTINUES;
 }
 
-static int zfcp_erp_lun_strategy_open(struct zfcp_erp_action *erp_action)
+static enum zfcp_erp_act_result zfcp_erp_lun_strategy_open(
+	struct zfcp_erp_action *erp_action)
 {
 	int retval = zfcp_fsf_open_lun(erp_action);
 	if (retval == -ENOMEM)
@@ -1046,7 +1059,8 @@ static int zfcp_erp_lun_strategy_open(struct zfcp_erp_action *erp_action)
 	return ZFCP_ERP_CONTINUES;
 }
 
-static int zfcp_erp_lun_strategy(struct zfcp_erp_action *erp_action)
+static enum zfcp_erp_act_result zfcp_erp_lun_strategy(
+	struct zfcp_erp_action *erp_action)
 {
 	struct scsi_device *sdev = erp_action->sdev;
 	struct zfcp_scsi_dev *zfcp_sdev = sdev_to_zfcp(sdev);
@@ -1077,7 +1091,8 @@ static int zfcp_erp_lun_strategy(struct zfcp_erp_action *erp_action)
 	return ZFCP_ERP_FAILED;
 }
 
-static int zfcp_erp_strategy_check_lun(struct scsi_device *sdev, int result)
+static enum zfcp_erp_act_result zfcp_erp_strategy_check_lun(
+	struct scsi_device *sdev, enum zfcp_erp_act_result result)
 {
 	struct zfcp_scsi_dev *zfcp_sdev = sdev_to_zfcp(sdev);
 
@@ -1098,6 +1113,12 @@ static int zfcp_erp_strategy_check_lun(struct scsi_device *sdev, int result)
 						ZFCP_STATUS_COMMON_ERP_FAILED);
 		}
 		break;
+	case ZFCP_ERP_CONTINUES:
+	case ZFCP_ERP_EXIT:
+	case ZFCP_ERP_DISMISSED:
+	case ZFCP_ERP_NOMEM:
+		/* NOP */
+		break;
 	}
 
 	if (atomic_read(&zfcp_sdev->status) & ZFCP_STATUS_COMMON_ERP_FAILED) {
@@ -1107,7 +1128,8 @@ static int zfcp_erp_strategy_check_lun(struct scsi_device *sdev, int result)
 	return result;
 }
 
-static int zfcp_erp_strategy_check_port(struct zfcp_port *port, int result)
+static enum zfcp_erp_act_result zfcp_erp_strategy_check_port(
+	struct zfcp_port *port, enum zfcp_erp_act_result result)
 {
 	switch (result) {
 	case ZFCP_ERP_SUCCEEDED :
@@ -1129,6 +1151,12 @@ static int zfcp_erp_strategy_check_port(struct zfcp_port *port, int result)
 					 ZFCP_STATUS_COMMON_ERP_FAILED);
 		}
 		break;
+	case ZFCP_ERP_CONTINUES:
+	case ZFCP_ERP_EXIT:
+	case ZFCP_ERP_DISMISSED:
+	case ZFCP_ERP_NOMEM:
+		/* NOP */
+		break;
 	}
 
 	if (atomic_read(&port->status) & ZFCP_STATUS_COMMON_ERP_FAILED) {
@@ -1138,8 +1166,8 @@ static int zfcp_erp_strategy_check_port(struct zfcp_port *port, int result)
 	return result;
 }
 
-static int zfcp_erp_strategy_check_adapter(struct zfcp_adapter *adapter,
-					   int result)
+static enum zfcp_erp_act_result zfcp_erp_strategy_check_adapter(
+	struct zfcp_adapter *adapter, enum zfcp_erp_act_result result)
 {
 	switch (result) {
 	case ZFCP_ERP_SUCCEEDED :
@@ -1157,6 +1185,12 @@ static int zfcp_erp_strategy_check_adapter(struct zfcp_adapter *adapter,
 					    ZFCP_STATUS_COMMON_ERP_FAILED);
 		}
 		break;
+	case ZFCP_ERP_CONTINUES:
+	case ZFCP_ERP_EXIT:
+	case ZFCP_ERP_DISMISSED:
+	case ZFCP_ERP_NOMEM:
+		/* NOP */
+		break;
 	}
 
 	if (atomic_read(&adapter->status) & ZFCP_STATUS_COMMON_ERP_FAILED) {
@@ -1166,8 +1200,8 @@ static int zfcp_erp_strategy_check_adapter(struct zfcp_adapter *adapter,
 	return result;
 }
 
-static int zfcp_erp_strategy_check_target(struct zfcp_erp_action *erp_action,
-					  int result)
+static enum zfcp_erp_act_result zfcp_erp_strategy_check_target(
+	struct zfcp_erp_action *erp_action, enum zfcp_erp_act_result result)
 {
 	struct zfcp_adapter *adapter = erp_action->adapter;
 	struct zfcp_port *port = erp_action->port;
@@ -1206,7 +1240,8 @@ static int zfcp_erp_strat_change_det(atomic_t *target_status, u32 erp_status)
 	return 0;
 }
 
-static int zfcp_erp_strategy_statechange(struct zfcp_erp_action *act, int ret)
+static enum zfcp_erp_act_result zfcp_erp_strategy_statechange(
+	struct zfcp_erp_action *act, enum zfcp_erp_act_result result)
 {
 	enum zfcp_erp_act_type type = act->type;
 	struct zfcp_adapter *adapter = act->adapter;
@@ -1245,7 +1280,7 @@ static int zfcp_erp_strategy_statechange(struct zfcp_erp_action *act, int ret)
 		}
 		break;
 	}
-	return ret;
+	return result;
 }
 
 static void zfcp_erp_action_dequeue(struct zfcp_erp_action *erp_action)
@@ -1338,7 +1373,8 @@ static void zfcp_erp_try_rport_unblock(struct zfcp_port *port)
 	write_unlock_irqrestore(&adapter->erp_lock, flags);
 }
 
-static void zfcp_erp_action_cleanup(struct zfcp_erp_action *act, int result)
+static void zfcp_erp_action_cleanup(struct zfcp_erp_action *act,
+				    enum zfcp_erp_act_result result)
 {
 	struct zfcp_adapter *adapter = act->adapter;
 	struct zfcp_port *port = act->port;
@@ -1378,7 +1414,8 @@ static void zfcp_erp_action_cleanup(struct zfcp_erp_action *act, int result)
 	}
 }
 
-static int zfcp_erp_strategy_do_action(struct zfcp_erp_action *erp_action)
+static enum zfcp_erp_act_result zfcp_erp_strategy_do_action(
+	struct zfcp_erp_action *erp_action)
 {
 	switch (erp_action->type) {
 	case ZFCP_ERP_ACTION_REOPEN_ADAPTER:
@@ -1393,9 +1430,10 @@ static int zfcp_erp_strategy_do_action(struct zfcp_erp_action *erp_action)
 	return ZFCP_ERP_FAILED;
 }
 
-static int zfcp_erp_strategy(struct zfcp_erp_action *erp_action)
+static enum zfcp_erp_act_result zfcp_erp_strategy(
+	struct zfcp_erp_action *erp_action)
 {
-	int retval;
+	enum zfcp_erp_act_result result;
 	unsigned long flags;
 	struct zfcp_adapter *adapter = erp_action->adapter;
 
@@ -1406,12 +1444,12 @@ static int zfcp_erp_strategy(struct zfcp_erp_action *erp_action)
 
 	if (erp_action->status & ZFCP_STATUS_ERP_DISMISSED) {
 		zfcp_erp_action_dequeue(erp_action);
-		retval = ZFCP_ERP_DISMISSED;
+		result = ZFCP_ERP_DISMISSED;
 		goto unlock;
 	}
 
 	if (erp_action->status & ZFCP_STATUS_ERP_TIMEDOUT) {
-		retval = ZFCP_ERP_FAILED;
+		result = ZFCP_ERP_FAILED;
 		goto check_target;
 	}
 
@@ -1419,13 +1457,13 @@ static int zfcp_erp_strategy(struct zfcp_erp_action *erp_action)
 
 	/* no lock to allow for blocking operations */
 	write_unlock_irqrestore(&adapter->erp_lock, flags);
-	retval = zfcp_erp_strategy_do_action(erp_action);
+	result = zfcp_erp_strategy_do_action(erp_action);
 	write_lock_irqsave(&adapter->erp_lock, flags);
 
 	if (erp_action->status & ZFCP_STATUS_ERP_DISMISSED)
-		retval = ZFCP_ERP_CONTINUES;
+		result = ZFCP_ERP_CONTINUES;
 
-	switch (retval) {
+	switch (result) {
 	case ZFCP_ERP_NOMEM:
 		if (!(erp_action->status & ZFCP_STATUS_ERP_LOWMEM)) {
 			++adapter->erp_low_mem_count;
@@ -1435,7 +1473,7 @@ static int zfcp_erp_strategy(struct zfcp_erp_action *erp_action)
 			_zfcp_erp_adapter_reopen(adapter, 0, "erstgy1");
 		else {
 			zfcp_erp_strategy_memwait(erp_action);
-			retval = ZFCP_ERP_CONTINUES;
+			result = ZFCP_ERP_CONTINUES;
 		}
 		goto unlock;
 
@@ -1445,27 +1483,33 @@ static int zfcp_erp_strategy(struct zfcp_erp_action *erp_action)
 			erp_action->status &= ~ZFCP_STATUS_ERP_LOWMEM;
 		}
 		goto unlock;
+	case ZFCP_ERP_SUCCEEDED:
+	case ZFCP_ERP_FAILED:
+	case ZFCP_ERP_EXIT:
+	case ZFCP_ERP_DISMISSED:
+		/* NOP */
+		break;
 	}
 
 check_target:
-	retval = zfcp_erp_strategy_check_target(erp_action, retval);
+	result = zfcp_erp_strategy_check_target(erp_action, result);
 	zfcp_erp_action_dequeue(erp_action);
-	retval = zfcp_erp_strategy_statechange(erp_action, retval);
-	if (retval == ZFCP_ERP_EXIT)
+	result = zfcp_erp_strategy_statechange(erp_action, result);
+	if (result == ZFCP_ERP_EXIT)
 		goto unlock;
-	if (retval == ZFCP_ERP_SUCCEEDED)
+	if (result == ZFCP_ERP_SUCCEEDED)
 		zfcp_erp_strategy_followup_success(erp_action);
-	if (retval == ZFCP_ERP_FAILED)
+	if (result == ZFCP_ERP_FAILED)
 		zfcp_erp_strategy_followup_failed(erp_action);
 
  unlock:
 	write_unlock_irqrestore(&adapter->erp_lock, flags);
 
-	if (retval != ZFCP_ERP_CONTINUES)
-		zfcp_erp_action_cleanup(erp_action, retval);
+	if (result != ZFCP_ERP_CONTINUES)
+		zfcp_erp_action_cleanup(erp_action, result);
 
 	kref_put(&adapter->ref, zfcp_adapter_release);
-	return retval;
+	return result;
 }
 
 static int zfcp_erp_thread(void *data)