1 files changed, 440 insertions, 204 deletions

diff --git a/drivers/s390/scsi/zfcp_erp.c b/drivers/s390/scsi/zfcp_erp.c
index 7ccfce559034..ec6c0e102119 100644
--- a/drivers/s390/scsi/zfcp_erp.c
+++ b/drivers/s390/scsi/zfcp_erp.c
@@ -1,50 +1,42 @@
+// SPDX-License-Identifier: GPL-2.0
 /*
  * zfcp device driver
  *
  * Error Recovery Procedures (ERP).
  *
- * Copyright IBM Corp. 2002, 2016
+ * Copyright IBM Corp. 2002, 2020
  */
 
-#define KMSG_COMPONENT "zfcp"
-#define pr_fmt(fmt) KMSG_COMPONENT ": " fmt
+#define pr_fmt(fmt) "zfcp: " fmt
 
 #include <linux/kthread.h>
+#include <linux/bug.h>
 #include "zfcp_ext.h"
 #include "zfcp_reqlist.h"
+#include "zfcp_diag.h"
 
 #define ZFCP_MAX_ERPS                   3
 
 enum zfcp_erp_act_flags {
 	ZFCP_STATUS_ERP_TIMEDOUT	= 0x10000000,
 	ZFCP_STATUS_ERP_CLOSE_ONLY	= 0x01000000,
-	ZFCP_STATUS_ERP_DISMISSING	= 0x00100000,
 	ZFCP_STATUS_ERP_DISMISSED	= 0x00200000,
 	ZFCP_STATUS_ERP_LOWMEM		= 0x00400000,
 	ZFCP_STATUS_ERP_NO_REF		= 0x00800000,
 };
 
-enum zfcp_erp_steps {
-	ZFCP_ERP_STEP_UNINITIALIZED	= 0x0000,
-	ZFCP_ERP_STEP_FSF_XCONFIG	= 0x0001,
-	ZFCP_ERP_STEP_PHYS_PORT_CLOSING	= 0x0010,
-	ZFCP_ERP_STEP_PORT_CLOSING	= 0x0100,
-	ZFCP_ERP_STEP_PORT_OPENING	= 0x0800,
-	ZFCP_ERP_STEP_LUN_CLOSING	= 0x1000,
-	ZFCP_ERP_STEP_LUN_OPENING	= 0x2000,
-};
-
-enum zfcp_erp_act_type {
-	ZFCP_ERP_ACTION_REOPEN_LUN         = 1,
-	ZFCP_ERP_ACTION_REOPEN_PORT	   = 2,
-	ZFCP_ERP_ACTION_REOPEN_PORT_FORCED = 3,
-	ZFCP_ERP_ACTION_REOPEN_ADAPTER     = 4,
-};
-
-enum zfcp_erp_act_state {
-	ZFCP_ERP_ACTION_RUNNING = 1,
-	ZFCP_ERP_ACTION_READY   = 2,
-};
+/*
+ * Eyecatcher pseudo flag to bitwise or-combine with enum zfcp_erp_act_type.
+ * Used to indicate that an ERP action could not be set up despite a detected
+ * need for some recovery.
+ */
+#define ZFCP_ERP_ACTION_NONE		0xc0
+/*
+ * Eyecatcher pseudo flag to bitwise or-combine with enum zfcp_erp_act_type.
+ * Used to indicate that ERP not needed because the object has
+ * ZFCP_STATUS_COMMON_ERP_FAILED.
+ */
+#define ZFCP_ERP_ACTION_FAILED		0xe0
 
 enum zfcp_erp_act_result {
 	ZFCP_ERP_SUCCEEDED = 0,
@@ -61,21 +53,21 @@ static void zfcp_erp_adapter_block(struct zfcp_adapter *adapter, int mask)
 				       ZFCP_STATUS_COMMON_UNBLOCKED | mask);
 }
 
-static int zfcp_erp_action_exists(struct zfcp_erp_action *act)
+static bool zfcp_erp_action_is_running(struct zfcp_erp_action *act)
 {
 	struct zfcp_erp_action *curr_act;
 
 	list_for_each_entry(curr_act, &act->adapter->erp_running_head, list)
 		if (act == curr_act)
-			return ZFCP_ERP_ACTION_RUNNING;
-	return 0;
+			return true;
+	return false;
 }
 
 static void zfcp_erp_action_ready(struct zfcp_erp_action *act)
 {
 	struct zfcp_adapter *adapter = act->adapter;
 
-	list_move(&act->list, &act->adapter->erp_ready_head);
+	list_move(&act->list, &adapter->erp_ready_head);
 	zfcp_dbf_rec_run("erardy1", act);
 	wake_up(&adapter->erp_ready_wq);
 	zfcp_dbf_rec_run("erardy2", act);
@@ -84,7 +76,7 @@ static void zfcp_erp_action_ready(struct zfcp_erp_action *act)
 static void zfcp_erp_action_dismiss(struct zfcp_erp_action *act)
 {
 	act->status |= ZFCP_STATUS_ERP_DISMISSED;
-	if (zfcp_erp_action_exists(act) == ZFCP_ERP_ACTION_RUNNING)
+	if (zfcp_erp_action_is_running(act))
 		zfcp_erp_action_ready(act);
 }
 
@@ -125,11 +117,52 @@ static void zfcp_erp_action_dismiss_adapter(struct zfcp_adapter *adapter)
 	}
 }
 
-static int zfcp_erp_required_act(int want, struct zfcp_adapter *adapter,
+static enum zfcp_erp_act_type zfcp_erp_handle_failed(
+	enum zfcp_erp_act_type want, struct zfcp_adapter *adapter,
+	struct zfcp_port *port,	struct scsi_device *sdev)
+{
+	enum zfcp_erp_act_type need = want;
+	struct zfcp_scsi_dev *zsdev;
+
+	switch (want) {
+	case ZFCP_ERP_ACTION_REOPEN_LUN:
+		zsdev = sdev_to_zfcp(sdev);
+		if (atomic_read(&zsdev->status) & ZFCP_STATUS_COMMON_ERP_FAILED)
+			need = 0;
+		break;
+	case ZFCP_ERP_ACTION_REOPEN_PORT_FORCED:
+		if (atomic_read(&port->status) & ZFCP_STATUS_COMMON_ERP_FAILED)
+			need = 0;
+		break;
+	case ZFCP_ERP_ACTION_REOPEN_PORT:
+		if (atomic_read(&port->status) &
+		    ZFCP_STATUS_COMMON_ERP_FAILED) {
+			need = 0;
+			/* ensure propagation of failed status to new devices */
+			zfcp_erp_set_port_status(
+				port, ZFCP_STATUS_COMMON_ERP_FAILED);
+		}
+		break;
+	case ZFCP_ERP_ACTION_REOPEN_ADAPTER:
+		if (atomic_read(&adapter->status) &
+		    ZFCP_STATUS_COMMON_ERP_FAILED) {
+			need = 0;
+			/* ensure propagation of failed status to new devices */
+			zfcp_erp_set_adapter_status(
+				adapter, ZFCP_STATUS_COMMON_ERP_FAILED);
+		}
+		break;
+	}
+
+	return need;
+}
+
+static enum zfcp_erp_act_type zfcp_erp_required_act(enum zfcp_erp_act_type want,
+				 struct zfcp_adapter *adapter,
 				 struct zfcp_port *port,
 				 struct scsi_device *sdev)
 {
-	int need = want;
+	enum zfcp_erp_act_type need = want;
 	int l_status, p_status, a_status;
 	struct zfcp_scsi_dev *zfcp_sdev;
 
@@ -141,29 +174,29 @@ static int zfcp_erp_required_act(int want, struct zfcp_adapter *adapter,
 			return 0;
 		p_status = atomic_read(&port->status);
 		if (!(p_status & ZFCP_STATUS_COMMON_RUNNING) ||
-		      p_status & ZFCP_STATUS_COMMON_ERP_FAILED)
+		    p_status & ZFCP_STATUS_COMMON_ERP_FAILED)
 			return 0;
 		if (!(p_status & ZFCP_STATUS_COMMON_UNBLOCKED))
 			need = ZFCP_ERP_ACTION_REOPEN_PORT;
-		/* fall through */
+		fallthrough;
 	case ZFCP_ERP_ACTION_REOPEN_PORT_FORCED:
 		p_status = atomic_read(&port->status);
 		if (!(p_status & ZFCP_STATUS_COMMON_OPEN))
 			need = ZFCP_ERP_ACTION_REOPEN_PORT;
-		/* fall through */
+		fallthrough;
 	case ZFCP_ERP_ACTION_REOPEN_PORT:
 		p_status = atomic_read(&port->status);
 		if (p_status & ZFCP_STATUS_COMMON_ERP_INUSE)
 			return 0;
 		a_status = atomic_read(&adapter->status);
 		if (!(a_status & ZFCP_STATUS_COMMON_RUNNING) ||
-		      a_status & ZFCP_STATUS_COMMON_ERP_FAILED)
+		    a_status & ZFCP_STATUS_COMMON_ERP_FAILED)
 			return 0;
 		if (p_status & ZFCP_STATUS_COMMON_NOESC)
 			return need;
 		if (!(a_status & ZFCP_STATUS_COMMON_UNBLOCKED))
 			need = ZFCP_ERP_ACTION_REOPEN_ADAPTER;
-		/* fall through */
+		fallthrough;
 	case ZFCP_ERP_ACTION_REOPEN_ADAPTER:
 		a_status = atomic_read(&adapter->status);
 		if (a_status & ZFCP_STATUS_COMMON_ERP_INUSE)
@@ -176,7 +209,8 @@ static int zfcp_erp_required_act(int want, struct zfcp_adapter *adapter,
 	return need;
 }
 
-static struct zfcp_erp_action *zfcp_erp_setup_act(int need, u32 act_status,
+static struct zfcp_erp_action *zfcp_erp_setup_act(enum zfcp_erp_act_type need,
+						  u32 act_status,
 						  struct zfcp_adapter *adapter,
 						  struct zfcp_port *port,
 						  struct scsi_device *sdev)
@@ -184,6 +218,12 @@ static struct zfcp_erp_action *zfcp_erp_setup_act(int need, u32 act_status,
 	struct zfcp_erp_action *erp_action;
 	struct zfcp_scsi_dev *zfcp_sdev;
 
+	if (WARN_ON_ONCE(need != ZFCP_ERP_ACTION_REOPEN_LUN &&
+			 need != ZFCP_ERP_ACTION_REOPEN_PORT &&
+			 need != ZFCP_ERP_ACTION_REOPEN_PORT_FORCED &&
+			 need != ZFCP_ERP_ACTION_REOPEN_ADAPTER))
+		return NULL;
+
 	switch (need) {
 	case ZFCP_ERP_ACTION_REOPEN_LUN:
 		zfcp_sdev = sdev_to_zfcp(sdev);
@@ -193,9 +233,8 @@ static struct zfcp_erp_action *zfcp_erp_setup_act(int need, u32 act_status,
 		atomic_or(ZFCP_STATUS_COMMON_ERP_INUSE,
 				&zfcp_sdev->status);
 		erp_action = &zfcp_sdev->erp_action;
-		memset(erp_action, 0, sizeof(struct zfcp_erp_action));
-		erp_action->port = port;
-		erp_action->sdev = sdev;
+		WARN_ON_ONCE(erp_action->port != port);
+		WARN_ON_ONCE(erp_action->sdev != sdev);
 		if (!(atomic_read(&zfcp_sdev->status) &
 		      ZFCP_STATUS_COMMON_RUNNING))
 			act_status |= ZFCP_STATUS_ERP_CLOSE_ONLY;
@@ -208,8 +247,8 @@ static struct zfcp_erp_action *zfcp_erp_setup_act(int need, u32 act_status,
 		zfcp_erp_action_dismiss_port(port);
 		atomic_or(ZFCP_STATUS_COMMON_ERP_INUSE, &port->status);
 		erp_action = &port->erp_action;
-		memset(erp_action, 0, sizeof(struct zfcp_erp_action));
-		erp_action->port = port;
+		WARN_ON_ONCE(erp_action->port != port);
+		WARN_ON_ONCE(erp_action->sdev != NULL);
 		if (!(atomic_read(&port->status) & ZFCP_STATUS_COMMON_RUNNING))
 			act_status |= ZFCP_STATUS_ERP_CLOSE_ONLY;
 		break;
@@ -219,74 +258,101 @@ static struct zfcp_erp_action *zfcp_erp_setup_act(int need, u32 act_status,
 		zfcp_erp_action_dismiss_adapter(adapter);
 		atomic_or(ZFCP_STATUS_COMMON_ERP_INUSE, &adapter->status);
 		erp_action = &adapter->erp_action;
-		memset(erp_action, 0, sizeof(struct zfcp_erp_action));
+		WARN_ON_ONCE(erp_action->port != NULL);
+		WARN_ON_ONCE(erp_action->sdev != NULL);
 		if (!(atomic_read(&adapter->status) &
 		      ZFCP_STATUS_COMMON_RUNNING))
 			act_status |= ZFCP_STATUS_ERP_CLOSE_ONLY;
 		break;
-
-	default:
-		return NULL;
 	}
 
-	erp_action->adapter = adapter;
-	erp_action->action = need;
+	WARN_ON_ONCE(erp_action->adapter != adapter);
+	memset(&erp_action->list, 0, sizeof(erp_action->list));
+	memset(&erp_action->timer, 0, sizeof(erp_action->timer));
+	erp_action->step = ZFCP_ERP_STEP_UNINITIALIZED;
+	erp_action->fsf_req_id = 0;
+	erp_action->type = need;
 	erp_action->status = act_status;
 
 	return erp_action;
 }
 
-static int zfcp_erp_action_enqueue(int want, struct zfcp_adapter *adapter,
-				   struct zfcp_port *port,
-				   struct scsi_device *sdev,
-				   char *id, u32 act_status)
+static void zfcp_erp_action_enqueue(enum zfcp_erp_act_type want,
+				    struct zfcp_adapter *adapter,
+				    struct zfcp_port *port,
+				    struct scsi_device *sdev,
+				    char *dbftag, u32 act_status)
 {
-	int retval = 1, need;
+	enum zfcp_erp_act_type need;
 	struct zfcp_erp_action *act;
 
-	if (!adapter->erp_thread)
-		return -EIO;
+	need = zfcp_erp_handle_failed(want, adapter, port, sdev);
+	if (!need) {
+		need = ZFCP_ERP_ACTION_FAILED; /* marker for trace */
+		goto out;
+	}
+
+	if (!adapter->erp_thread) {
+		need = ZFCP_ERP_ACTION_NONE; /* marker for trace */
+		goto out;
+	}
 
 	need = zfcp_erp_required_act(want, adapter, port, sdev);
 	if (!need)
 		goto out;
 
 	act = zfcp_erp_setup_act(need, act_status, adapter, port, sdev);
-	if (!act)
+	if (!act) {
+		need |= ZFCP_ERP_ACTION_NONE; /* marker for trace */
 		goto out;
+	}
 	atomic_or(ZFCP_STATUS_ADAPTER_ERP_PENDING, &adapter->status);
 	++adapter->erp_total_count;
 	list_add_tail(&act->list, &adapter->erp_ready_head);
 	wake_up(&adapter->erp_ready_wq);
-	retval = 0;
  out:
-	zfcp_dbf_rec_trig(id, adapter, port, sdev, want, need);
-	return retval;
+	zfcp_dbf_rec_trig(dbftag, adapter, port, sdev, want, need);
 }
 
-static int _zfcp_erp_adapter_reopen(struct zfcp_adapter *adapter,
-				    int clear_mask, char *id)
+void zfcp_erp_port_forced_no_port_dbf(char *dbftag,
+				      struct zfcp_adapter *adapter,
+				      u64 port_name, u32 port_id)
+{
+	unsigned long flags;
+	static /* don't waste stack */ struct zfcp_port tmpport;
+
+	write_lock_irqsave(&adapter->erp_lock, flags);
+	/* Stand-in zfcp port with fields just good enough for
+	 * zfcp_dbf_rec_trig() and zfcp_dbf_set_common().
+	 * Under lock because tmpport is static.
+	 */
+	atomic_set(&tmpport.status, -1); /* unknown */
+	tmpport.wwpn = port_name;
+	tmpport.d_id = port_id;
+	zfcp_dbf_rec_trig(dbftag, adapter, &tmpport, NULL,
+			  ZFCP_ERP_ACTION_REOPEN_PORT_FORCED,
+			  ZFCP_ERP_ACTION_NONE);
+	write_unlock_irqrestore(&adapter->erp_lock, flags);
+}
+
+static void _zfcp_erp_adapter_reopen(struct zfcp_adapter *adapter,
+				    int clear_mask, char *dbftag)
 {
 	zfcp_erp_adapter_block(adapter, clear_mask);
 	zfcp_scsi_schedule_rports_block(adapter);
 
-	/* ensure propagation of failed status to new devices */
-	if (atomic_read(&adapter->status) & ZFCP_STATUS_COMMON_ERP_FAILED) {
-		zfcp_erp_set_adapter_status(adapter,
-					    ZFCP_STATUS_COMMON_ERP_FAILED);
-		return -EIO;
-	}
-	return zfcp_erp_action_enqueue(ZFCP_ERP_ACTION_REOPEN_ADAPTER,
-				       adapter, NULL, NULL, id, 0);
+	zfcp_erp_action_enqueue(ZFCP_ERP_ACTION_REOPEN_ADAPTER,
+				adapter, NULL, NULL, dbftag, 0);
 }
 
 /**
  * zfcp_erp_adapter_reopen - Reopen adapter.
  * @adapter: Adapter to reopen.
  * @clear: Status flags to clear.
- * @id: Id for debug trace event.
+ * @dbftag: Tag for debug trace event.
  */
-void zfcp_erp_adapter_reopen(struct zfcp_adapter *adapter, int clear, char *id)
+void zfcp_erp_adapter_reopen(struct zfcp_adapter *adapter, int clear,
+			     char *dbftag)
 {
 	unsigned long flags;
 
@@ -294,12 +360,8 @@ void zfcp_erp_adapter_reopen(struct zfcp_adapter *adapter, int clear, char *id)
 	zfcp_scsi_schedule_rports_block(adapter);
 
 	write_lock_irqsave(&adapter->erp_lock, flags);
-	if (atomic_read(&adapter->status) & ZFCP_STATUS_COMMON_ERP_FAILED)
-		zfcp_erp_set_adapter_status(adapter,
-					    ZFCP_STATUS_COMMON_ERP_FAILED);
-	else
-		zfcp_erp_action_enqueue(ZFCP_ERP_ACTION_REOPEN_ADAPTER, adapter,
-					NULL, NULL, id, 0);
+	zfcp_erp_action_enqueue(ZFCP_ERP_ACTION_REOPEN_ADAPTER, adapter,
+				NULL, NULL, dbftag, 0);
 	write_unlock_irqrestore(&adapter->erp_lock, flags);
 }
 
@@ -307,25 +369,25 @@ void zfcp_erp_adapter_reopen(struct zfcp_adapter *adapter, int clear, char *id)
  * zfcp_erp_adapter_shutdown - Shutdown adapter.
  * @adapter: Adapter to shut down.
  * @clear: Status flags to clear.
- * @id: Id for debug trace event.
+ * @dbftag: Tag for debug trace event.
  */
 void zfcp_erp_adapter_shutdown(struct zfcp_adapter *adapter, int clear,
-			       char *id)
+			       char *dbftag)
 {
 	int flags = ZFCP_STATUS_COMMON_RUNNING | ZFCP_STATUS_COMMON_ERP_FAILED;
-	zfcp_erp_adapter_reopen(adapter, clear | flags, id);
+	zfcp_erp_adapter_reopen(adapter, clear | flags, dbftag);
 }
 
 /**
  * zfcp_erp_port_shutdown - Shutdown port
  * @port: Port to shut down.
  * @clear: Status flags to clear.
- * @id: Id for debug trace event.
+ * @dbftag: Tag for debug trace event.
  */
-void zfcp_erp_port_shutdown(struct zfcp_port *port, int clear, char *id)
+void zfcp_erp_port_shutdown(struct zfcp_port *port, int clear, char *dbftag)
 {
 	int flags = ZFCP_STATUS_COMMON_RUNNING | ZFCP_STATUS_COMMON_ERP_FAILED;
-	zfcp_erp_port_reopen(port, clear | flags, id);
+	zfcp_erp_port_reopen(port, clear | flags, dbftag);
 }
 
 static void zfcp_erp_port_block(struct zfcp_port *port, int clear)
@@ -335,68 +397,56 @@ static void zfcp_erp_port_block(struct zfcp_port *port, int clear)
 }
 
 static void _zfcp_erp_port_forced_reopen(struct zfcp_port *port, int clear,
-					 char *id)
+					 char *dbftag)
 {
 	zfcp_erp_port_block(port, clear);
 	zfcp_scsi_schedule_rport_block(port);
 
-	if (atomic_read(&port->status) & ZFCP_STATUS_COMMON_ERP_FAILED)
-		return;
-
 	zfcp_erp_action_enqueue(ZFCP_ERP_ACTION_REOPEN_PORT_FORCED,
-				port->adapter, port, NULL, id, 0);
+				port->adapter, port, NULL, dbftag, 0);
 }
 
 /**
  * zfcp_erp_port_forced_reopen - Forced close of port and open again
  * @port: Port to force close and to reopen.
  * @clear: Status flags to clear.
- * @id: Id for debug trace event.
+ * @dbftag: Tag for debug trace event.
  */
-void zfcp_erp_port_forced_reopen(struct zfcp_port *port, int clear, char *id)
+void zfcp_erp_port_forced_reopen(struct zfcp_port *port, int clear,
+				 char *dbftag)
 {
 	unsigned long flags;
 	struct zfcp_adapter *adapter = port->adapter;
 
 	write_lock_irqsave(&adapter->erp_lock, flags);
-	_zfcp_erp_port_forced_reopen(port, clear, id);
+	_zfcp_erp_port_forced_reopen(port, clear, dbftag);
 	write_unlock_irqrestore(&adapter->erp_lock, flags);
 }
 
-static int _zfcp_erp_port_reopen(struct zfcp_port *port, int clear, char *id)
+static void _zfcp_erp_port_reopen(struct zfcp_port *port, int clear,
+				  char *dbftag)
 {
 	zfcp_erp_port_block(port, clear);
 	zfcp_scsi_schedule_rport_block(port);
 
-	if (atomic_read(&port->status) & ZFCP_STATUS_COMMON_ERP_FAILED) {
-		/* ensure propagation of failed status to new devices */
-		zfcp_erp_set_port_status(port, ZFCP_STATUS_COMMON_ERP_FAILED);
-		return -EIO;
-	}
-
-	return zfcp_erp_action_enqueue(ZFCP_ERP_ACTION_REOPEN_PORT,
-				       port->adapter, port, NULL, id, 0);
+	zfcp_erp_action_enqueue(ZFCP_ERP_ACTION_REOPEN_PORT,
+				port->adapter, port, NULL, dbftag, 0);
 }
 
 /**
  * zfcp_erp_port_reopen - trigger remote port recovery
  * @port: port to recover
- * @clear_mask: flags in port status to be cleared
- * @id: Id for debug trace event.
- *
- * Returns 0 if recovery has been triggered, < 0 if not.
+ * @clear: flags in port status to be cleared
+ * @dbftag: Tag for debug trace event.
  */
-int zfcp_erp_port_reopen(struct zfcp_port *port, int clear, char *id)
+void zfcp_erp_port_reopen(struct zfcp_port *port, int clear, char *dbftag)
 {
-	int retval;
 	unsigned long flags;
 	struct zfcp_adapter *adapter = port->adapter;
 
 	write_lock_irqsave(&adapter->erp_lock, flags);
-	retval = _zfcp_erp_port_reopen(port, clear, id);
+	_zfcp_erp_port_reopen(port, clear, dbftag);
 	write_unlock_irqrestore(&adapter->erp_lock, flags);
-
-	return retval;
 }
 
 static void zfcp_erp_lun_block(struct scsi_device *sdev, int clear_mask)
@@ -405,30 +455,27 @@ static void zfcp_erp_lun_block(struct scsi_device *sdev, int clear_mask)
 				  ZFCP_STATUS_COMMON_UNBLOCKED | clear_mask);
 }
 
-static void _zfcp_erp_lun_reopen(struct scsi_device *sdev, int clear, char *id,
-				 u32 act_status)
+static void _zfcp_erp_lun_reopen(struct scsi_device *sdev, int clear,
+				 char *dbftag, u32 act_status)
 {
 	struct zfcp_scsi_dev *zfcp_sdev = sdev_to_zfcp(sdev);
 	struct zfcp_adapter *adapter = zfcp_sdev->port->adapter;
 
 	zfcp_erp_lun_block(sdev, clear);
 
-	if (atomic_read(&zfcp_sdev->status) & ZFCP_STATUS_COMMON_ERP_FAILED)
-		return;
-
 	zfcp_erp_action_enqueue(ZFCP_ERP_ACTION_REOPEN_LUN, adapter,
-				zfcp_sdev->port, sdev, id, act_status);
+				zfcp_sdev->port, sdev, dbftag, act_status);
 }
 
 /**
  * zfcp_erp_lun_reopen - initiate reopen of a LUN
  * @sdev: SCSI device / LUN to be reopened
- * @clear_mask: specifies flags in LUN status to be cleared
- * @id: Id for debug trace event.
+ * @clear: specifies flags in LUN status to be cleared
+ * @dbftag: Tag for debug trace event.
  *
  * Return: 0 on success, < 0 on error
  */
-void zfcp_erp_lun_reopen(struct scsi_device *sdev, int clear, char *id)
+void zfcp_erp_lun_reopen(struct scsi_device *sdev, int clear, char *dbftag)
 {
 	unsigned long flags;
 	struct zfcp_scsi_dev *zfcp_sdev = sdev_to_zfcp(sdev);
@@ -436,7 +483,7 @@ void zfcp_erp_lun_reopen(struct scsi_device *sdev, int clear, char *id)
 	struct zfcp_adapter *adapter = port->adapter;
 
 	write_lock_irqsave(&adapter->erp_lock, flags);
-	_zfcp_erp_lun_reopen(sdev, clear, id, 0);
+	_zfcp_erp_lun_reopen(sdev, clear, dbftag, 0);
 	write_unlock_irqrestore(&adapter->erp_lock, flags);
 }
 
@@ -444,25 +491,25 @@ void zfcp_erp_lun_reopen(struct scsi_device *sdev, int clear, char *id)
  * zfcp_erp_lun_shutdown - Shutdown LUN
  * @sdev: SCSI device / LUN to shut down.
  * @clear: Status flags to clear.
- * @id: Id for debug trace event.
+ * @dbftag: Tag for debug trace event.
  */
-void zfcp_erp_lun_shutdown(struct scsi_device *sdev, int clear, char *id)
+void zfcp_erp_lun_shutdown(struct scsi_device *sdev, int clear, char *dbftag)
 {
 	int flags = ZFCP_STATUS_COMMON_RUNNING | ZFCP_STATUS_COMMON_ERP_FAILED;
-	zfcp_erp_lun_reopen(sdev, clear | flags, id);
+	zfcp_erp_lun_reopen(sdev, clear | flags, dbftag);
 }
 
 /**
  * zfcp_erp_lun_shutdown_wait - Shutdown LUN and wait for erp completion
  * @sdev: SCSI device / LUN to shut down.
- * @id: Id for debug trace event.
+ * @dbftag: Tag for debug trace event.
  *
  * Do not acquire a reference for the LUN when creating the ERP
  * action. It is safe, because this function waits for the ERP to
  * complete first. This allows to shutdown the LUN, even when the SCSI
  * device is in the state SDEV_DEL when scsi_device_get will fail.
  */
-void zfcp_erp_lun_shutdown_wait(struct scsi_device *sdev, char *id)
+void zfcp_erp_lun_shutdown_wait(struct scsi_device *sdev, char *dbftag)
 {
 	unsigned long flags;
 	struct zfcp_scsi_dev *zfcp_sdev = sdev_to_zfcp(sdev);
@@ -471,27 +518,29 @@ void zfcp_erp_lun_shutdown_wait(struct scsi_device *sdev, char *id)
 	int clear = ZFCP_STATUS_COMMON_RUNNING | ZFCP_STATUS_COMMON_ERP_FAILED;
 
 	write_lock_irqsave(&adapter->erp_lock, flags);
-	_zfcp_erp_lun_reopen(sdev, clear, id, ZFCP_STATUS_ERP_NO_REF);
+	_zfcp_erp_lun_reopen(sdev, clear, dbftag, ZFCP_STATUS_ERP_NO_REF);
 	write_unlock_irqrestore(&adapter->erp_lock, flags);
 
 	zfcp_erp_wait(adapter);
 }
 
-static int status_change_set(unsigned long mask, atomic_t *status)
+static int zfcp_erp_status_change_set(unsigned long mask, atomic_t *status)
 {
 	return (atomic_read(status) ^ mask) & mask;
 }
 
 static void zfcp_erp_adapter_unblock(struct zfcp_adapter *adapter)
 {
-	if (status_change_set(ZFCP_STATUS_COMMON_UNBLOCKED, &adapter->status))
+	if (zfcp_erp_status_change_set(ZFCP_STATUS_COMMON_UNBLOCKED,
+				       &adapter->status))
 		zfcp_dbf_rec_run("eraubl1", &adapter->erp_action);
 	atomic_or(ZFCP_STATUS_COMMON_UNBLOCKED, &adapter->status);
 }
 
 static void zfcp_erp_port_unblock(struct zfcp_port *port)
 {
-	if (status_change_set(ZFCP_STATUS_COMMON_UNBLOCKED, &port->status))
+	if (zfcp_erp_status_change_set(ZFCP_STATUS_COMMON_UNBLOCKED,
+				       &port->status))
 		zfcp_dbf_rec_run("erpubl1", &port->erp_action);
 	atomic_or(ZFCP_STATUS_COMMON_UNBLOCKED, &port->status);
 }
@@ -500,7 +549,8 @@ static void zfcp_erp_lun_unblock(struct scsi_device *sdev)
 {
 	struct zfcp_scsi_dev *zfcp_sdev = sdev_to_zfcp(sdev);
 
-	if (status_change_set(ZFCP_STATUS_COMMON_UNBLOCKED, &zfcp_sdev->status))
+	if (zfcp_erp_status_change_set(ZFCP_STATUS_COMMON_UNBLOCKED,
+				       &zfcp_sdev->status))
 		zfcp_dbf_rec_run("erlubl1", &sdev_to_zfcp(sdev)->erp_action);
 	atomic_or(ZFCP_STATUS_COMMON_UNBLOCKED, &zfcp_sdev->status);
 }
@@ -526,7 +576,10 @@ static void zfcp_erp_strategy_check_fsfreq(struct zfcp_erp_action *act)
 				   ZFCP_STATUS_ERP_TIMEDOUT)) {
 			req->status |= ZFCP_STATUS_FSFREQ_DISMISSED;
 			zfcp_dbf_rec_run("erscf_1", act);
-			req->erp_action = NULL;
+			/* lock-free concurrent access with
+			 * zfcp_erp_timeout_handler()
+			 */
+			WRITE_ONCE(req->erp_action, NULL);
 		}
 		if (act->status & ZFCP_STATUS_ERP_TIMEDOUT)
 			zfcp_dbf_rec_run("erscf_2", act);
@@ -548,7 +601,7 @@ void zfcp_erp_notify(struct zfcp_erp_action *erp_action, unsigned long set_mask)
 	unsigned long flags;
 
 	write_lock_irqsave(&adapter->erp_lock, flags);
-	if (zfcp_erp_action_exists(erp_action) == ZFCP_ERP_ACTION_RUNNING) {
+	if (zfcp_erp_action_is_running(erp_action)) {
 		erp_action->status |= set_mask;
 		zfcp_erp_action_ready(erp_action);
 	}
@@ -557,54 +610,76 @@ void zfcp_erp_notify(struct zfcp_erp_action *erp_action, unsigned long set_mask)
 
 /**
  * zfcp_erp_timeout_handler - Trigger ERP action from timed out ERP request
- * @data: ERP action (from timer data)
+ * @t: timer list entry embedded in zfcp FSF request
  */
-void zfcp_erp_timeout_handler(unsigned long data)
+void zfcp_erp_timeout_handler(struct timer_list *t)
 {
-	struct zfcp_erp_action *act = (struct zfcp_erp_action *) data;
+	struct zfcp_fsf_req *fsf_req = timer_container_of(fsf_req, t, timer);
+	struct zfcp_erp_action *act;
+
+	if (fsf_req->status & ZFCP_STATUS_FSFREQ_DISMISSED)
+		return;
+	/* lock-free concurrent access with zfcp_erp_strategy_check_fsfreq() */
+	act = READ_ONCE(fsf_req->erp_action);
+	if (!act)
+		return;
 	zfcp_erp_notify(act, ZFCP_STATUS_ERP_TIMEDOUT);
 }
 
-static void zfcp_erp_memwait_handler(unsigned long data)
+static void zfcp_erp_memwait_handler(struct timer_list *t)
 {
-	zfcp_erp_notify((struct zfcp_erp_action *)data, 0);
+	struct zfcp_erp_action *act = timer_container_of(act, t, timer);
+
+	zfcp_erp_notify(act, 0);
 }
 
 static void zfcp_erp_strategy_memwait(struct zfcp_erp_action *erp_action)
 {
-	init_timer(&erp_action->timer);
-	erp_action->timer.function = zfcp_erp_memwait_handler;
-	erp_action->timer.data = (unsigned long) erp_action;
+	timer_setup(&erp_action->timer, zfcp_erp_memwait_handler, 0);
 	erp_action->timer.expires = jiffies + HZ;
 	add_timer(&erp_action->timer);
 }
 
+void zfcp_erp_port_forced_reopen_all(struct zfcp_adapter *adapter,
+				     int clear, char *dbftag)
+{
+	unsigned long flags;
+	struct zfcp_port *port;
+
+	write_lock_irqsave(&adapter->erp_lock, flags);
+	read_lock(&adapter->port_list_lock);
+	list_for_each_entry(port, &adapter->port_list, list)
+		_zfcp_erp_port_forced_reopen(port, clear, dbftag);
+	read_unlock(&adapter->port_list_lock);
+	write_unlock_irqrestore(&adapter->erp_lock, flags);
+}
+
 static void _zfcp_erp_port_reopen_all(struct zfcp_adapter *adapter,
-				      int clear, char *id)
+				      int clear, char *dbftag)
 {
 	struct zfcp_port *port;
 
 	read_lock(&adapter->port_list_lock);
 	list_for_each_entry(port, &adapter->port_list, list)
-		_zfcp_erp_port_reopen(port, clear, id);
+		_zfcp_erp_port_reopen(port, clear, dbftag);
 	read_unlock(&adapter->port_list_lock);
 }
 
 static void _zfcp_erp_lun_reopen_all(struct zfcp_port *port, int clear,
-				     char *id)
+				     char *dbftag)
 {
 	struct scsi_device *sdev;
 
 	spin_lock(port->adapter->scsi_host->host_lock);
 	__shost_for_each_device(sdev, port->adapter->scsi_host)
 		if (sdev_to_zfcp(sdev)->port == port)
-			_zfcp_erp_lun_reopen(sdev, clear, id, 0);
+			_zfcp_erp_lun_reopen(sdev, clear, dbftag, 0);
 	spin_unlock(port->adapter->scsi_host->host_lock);
 }
 
 static void zfcp_erp_strategy_followup_failed(struct zfcp_erp_action *act)
 {
-	switch (act->action) {
+	switch (act->type) {
 	case ZFCP_ERP_ACTION_REOPEN_ADAPTER:
 		_zfcp_erp_adapter_reopen(act->adapter, 0, "ersff_1");
 		break;
@@ -622,7 +697,7 @@ static void zfcp_erp_strategy_followup_failed(struct zfcp_erp_action *act)
 
 static void zfcp_erp_strategy_followup_success(struct zfcp_erp_action *act)
 {
-	switch (act->action) {
+	switch (act->type) {
 	case ZFCP_ERP_ACTION_REOPEN_ADAPTER:
 		_zfcp_erp_port_reopen_all(act->adapter, 0, "ersfs_1");
 		break;
@@ -632,6 +707,9 @@ static void zfcp_erp_strategy_followup_success(struct zfcp_erp_action *act)
 	case ZFCP_ERP_ACTION_REOPEN_PORT:
 		_zfcp_erp_lun_reopen_all(act->port, 0, "ersfs_3");
 		break;
+	case ZFCP_ERP_ACTION_REOPEN_LUN:
+		/* NOP */
+		break;
 	}
 }
 
@@ -656,10 +734,11 @@ static void zfcp_erp_enqueue_ptp_port(struct zfcp_adapter *adapter)
 				 adapter->peer_d_id);
 	if (IS_ERR(port)) /* error or port already attached */
 		return;
-	_zfcp_erp_port_reopen(port, 0, "ereptp1");
+	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;
@@ -698,13 +777,18 @@ static int zfcp_erp_adapter_strat_fsf_xconf(struct zfcp_erp_action *erp_action)
 	if (!(atomic_read(&adapter->status) & ZFCP_STATUS_ADAPTER_XCONFIG_OK))
 		return ZFCP_ERP_FAILED;
 
+	return ZFCP_ERP_SUCCEEDED;
+}
+
+static void
+zfcp_erp_adapter_strategy_open_ptp_port(struct zfcp_adapter *const adapter)
+{
 	if (fc_host_port_type(adapter->scsi_host) == FC_PORTTYPE_PTP)
 		zfcp_erp_enqueue_ptp_port(adapter);
-
-	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;
@@ -729,7 +813,61 @@ 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_alloc_shost(struct zfcp_adapter *const adapter)
+{
+	struct zfcp_diag_adapter_config_data *const config_data =
+		&adapter->diagnostics->config_data;
+	struct zfcp_diag_adapter_port_data *const port_data =
+		&adapter->diagnostics->port_data;
+	unsigned long flags;
+	int rc;
+
+	rc = zfcp_scsi_adapter_register(adapter);
+	if (rc == -EEXIST)
+		return ZFCP_ERP_SUCCEEDED;
+	else if (rc)
+		return ZFCP_ERP_FAILED;
+
+	/*
+	 * We allocated the shost for the first time. Before it was NULL,
+	 * and so we deferred all updates in the xconf- and xport-data
+	 * handlers. We need to make up for that now, and make all the updates
+	 * that would have been done before.
+	 *
+	 * We can be sure that xconf- and xport-data succeeded, because
+	 * otherwise this function is not called. But they might have been
+	 * incomplete.
+	 */
+
+	spin_lock_irqsave(&config_data->header.access_lock, flags);
+	zfcp_scsi_shost_update_config_data(adapter, &config_data->data,
+					   !!config_data->header.incomplete);
+	spin_unlock_irqrestore(&config_data->header.access_lock, flags);
+
+	if (adapter->adapter_features & FSF_FEATURE_HBAAPI_MANAGEMENT) {
+		spin_lock_irqsave(&port_data->header.access_lock, flags);
+		zfcp_scsi_shost_update_port_data(adapter, &port_data->data);
+		spin_unlock_irqrestore(&port_data->header.access_lock, flags);
+	}
+
+	/*
+	 * There is a remote possibility that the 'Exchange Port Data' request
+	 * reports a different connectivity status than 'Exchange Config Data'.
+	 * But any change to the connectivity status of the local optic that
+	 * happens after the initial xconf request is expected to be reported
+	 * to us, as soon as we post Status Read Buffers to the FCP channel
+	 * firmware after this function. So any resulting inconsistency will
+	 * only be momentary.
+	 */
+	if (config_data->header.incomplete)
+		zfcp_fsf_fc_host_link_down(adapter);
+
+	return ZFCP_ERP_SUCCEEDED;
+}
+
+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;
@@ -737,6 +875,12 @@ static int zfcp_erp_adapter_strategy_open_fsf(struct zfcp_erp_action *act)
 	if (zfcp_erp_adapter_strategy_open_fsf_xport(act) == ZFCP_ERP_FAILED)
 		return ZFCP_ERP_FAILED;
 
+	if (zfcp_erp_adapter_strategy_alloc_shost(act->adapter) ==
+	    ZFCP_ERP_FAILED)
+		return ZFCP_ERP_FAILED;
+
+	zfcp_erp_adapter_strategy_open_ptp_port(act->adapter);
+
 	if (mempool_resize(act->adapter->pool.sr_data,
 			   act->adapter->stat_read_buf_num))
 		return ZFCP_ERP_FAILED;
@@ -768,7 +912,8 @@ 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;
 
@@ -789,7 +934,8 @@ 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;
 
@@ -807,7 +953,8 @@ 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;
 
@@ -821,7 +968,8 @@ 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);
@@ -837,11 +985,19 @@ static int zfcp_erp_port_forced_strategy(struct zfcp_erp_action *erp_action)
 	case ZFCP_ERP_STEP_PHYS_PORT_CLOSING:
 		if (!(status & ZFCP_STATUS_PORT_PHYS_OPEN))
 			return ZFCP_ERP_SUCCEEDED;
+		break;
+	case ZFCP_ERP_STEP_PORT_CLOSING:
+	case ZFCP_ERP_STEP_PORT_OPENING:
+	case ZFCP_ERP_STEP_LUN_CLOSING:
+	case ZFCP_ERP_STEP_LUN_OPENING:
+		/* NOP */
+		break;
 	}
 	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;
 
@@ -854,7 +1010,8 @@ 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;
 
@@ -880,7 +1037,8 @@ 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;
@@ -911,12 +1069,18 @@ static int zfcp_erp_port_strategy_open_common(struct zfcp_erp_action *act)
 			port->d_id = 0;
 			return ZFCP_ERP_FAILED;
 		}
-		/* fall through otherwise */
+		/* no early return otherwise, continue after switch case */
+		break;
+	case ZFCP_ERP_STEP_LUN_CLOSING:
+	case ZFCP_ERP_STEP_LUN_OPENING:
+		/* NOP */
+		break;
 	}
 	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);
@@ -935,6 +1099,12 @@ static int zfcp_erp_port_strategy(struct zfcp_erp_action *erp_action)
 		if (p_status & ZFCP_STATUS_COMMON_OPEN)
 			return ZFCP_ERP_FAILED;
 		break;
+	case ZFCP_ERP_STEP_PHYS_PORT_CLOSING:
+	case ZFCP_ERP_STEP_PORT_OPENING:
+	case ZFCP_ERP_STEP_LUN_CLOSING:
+	case ZFCP_ERP_STEP_LUN_OPENING:
+		/* NOP */
+		break;
 	}
 
 close_init_done:
@@ -952,7 +1122,8 @@ 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)
@@ -963,7 +1134,8 @@ 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)
@@ -974,7 +1146,8 @@ 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);
@@ -984,7 +1157,8 @@ static int zfcp_erp_lun_strategy(struct zfcp_erp_action *erp_action)
 		zfcp_erp_lun_strategy_clearstati(sdev);
 		if (atomic_read(&zfcp_sdev->status) & ZFCP_STATUS_COMMON_OPEN)
 			return zfcp_erp_lun_strategy_close(erp_action);
-		/* already closed, fall through */
+		/* already closed */
+		fallthrough;
 	case ZFCP_ERP_STEP_LUN_CLOSING:
 		if (atomic_read(&zfcp_sdev->status) & ZFCP_STATUS_COMMON_OPEN)
 			return ZFCP_ERP_FAILED;
@@ -995,11 +1169,18 @@ static int zfcp_erp_lun_strategy(struct zfcp_erp_action *erp_action)
 	case ZFCP_ERP_STEP_LUN_OPENING:
 		if (atomic_read(&zfcp_sdev->status) & ZFCP_STATUS_COMMON_OPEN)
 			return ZFCP_ERP_SUCCEEDED;
+		break;
+	case ZFCP_ERP_STEP_PHYS_PORT_CLOSING:
+	case ZFCP_ERP_STEP_PORT_CLOSING:
+	case ZFCP_ERP_STEP_PORT_OPENING:
+		/* NOP */
+		break;
 	}
 	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);
 
@@ -1020,6 +1201,12 @@ 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) {
@@ -1029,7 +1216,8 @@ 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 :
@@ -1051,6 +1239,12 @@ 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) {
@@ -1060,8 +1254,8 @@ 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 :
@@ -1079,6 +1273,12 @@ 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) {
@@ -1088,14 +1288,14 @@ 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;
 	struct scsi_device *sdev = erp_action->sdev;
 
-	switch (erp_action->action) {
+	switch (erp_action->type) {
 
 	case ZFCP_ERP_ACTION_REOPEN_LUN:
 		result = zfcp_erp_strategy_check_lun(sdev, result);
@@ -1128,16 +1328,17 @@ 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)
 {
-	int action = act->action;
+	enum zfcp_erp_act_type type = act->type;
 	struct zfcp_adapter *adapter = act->adapter;
 	struct zfcp_port *port = act->port;
 	struct scsi_device *sdev = act->sdev;
 	struct zfcp_scsi_dev *zfcp_sdev;
 	u32 erp_status = act->status;
 
-	switch (action) {
+	switch (type) {
 	case ZFCP_ERP_ACTION_REOPEN_ADAPTER:
 		if (zfcp_erp_strat_change_det(&adapter->status, erp_status)) {
 			_zfcp_erp_adapter_reopen(adapter,
@@ -1167,7 +1368,7 @@ 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)
@@ -1184,7 +1385,7 @@ static void zfcp_erp_action_dequeue(struct zfcp_erp_action *erp_action)
 	list_del(&erp_action->list);
 	zfcp_dbf_rec_run("eractd1", erp_action);
 
-	switch (erp_action->action) {
+	switch (erp_action->type) {
 	case ZFCP_ERP_ACTION_REOPEN_LUN:
 		zfcp_sdev = sdev_to_zfcp(erp_action->sdev);
 		atomic_andnot(ZFCP_STATUS_COMMON_ERP_INUSE,
@@ -1233,6 +1434,9 @@ static void zfcp_erp_try_rport_unblock(struct zfcp_port *port)
 		struct zfcp_scsi_dev *zsdev = sdev_to_zfcp(sdev);
 		int lun_status;
 
+		if (sdev->sdev_state == SDEV_DEL ||
+		    sdev->sdev_state == SDEV_CANCEL)
+			continue;
 		if (zsdev->port != port)
 			continue;
 		/* LUN under port of interest */
@@ -1260,13 +1464,14 @@ 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;
 	struct scsi_device *sdev = act->sdev;
 
-	switch (act->action) {
+	switch (act->type) {
 	case ZFCP_ERP_ACTION_REOPEN_LUN:
 		if (!(act->status & ZFCP_STATUS_ERP_NO_REF))
 			scsi_device_put(sdev);
@@ -1282,7 +1487,7 @@ static void zfcp_erp_action_cleanup(struct zfcp_erp_action *act, int result)
 		if (act->step != ZFCP_ERP_STEP_UNINITIALIZED)
 			if (result == ZFCP_ERP_SUCCEEDED)
 				zfcp_erp_try_rport_unblock(port);
-		/* fall through */
+		fallthrough;
 	case ZFCP_ERP_ACTION_REOPEN_PORT_FORCED:
 		put_device(&port->dev);
 		break;
@@ -1300,9 +1505,10 @@ 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->action) {
+	switch (erp_action->type) {
 	case ZFCP_ERP_ACTION_REOPEN_ADAPTER:
 		return zfcp_erp_adapter_strategy(erp_action);
 	case ZFCP_ERP_ACTION_REOPEN_PORT_FORCED:
@@ -1315,9 +1521,10 @@ 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;
 
@@ -1328,12 +1535,12 @@ 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;
 	}
 
@@ -1341,13 +1548,13 @@ 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;
@@ -1357,7 +1564,7 @@ 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;
 
@@ -1367,33 +1574,38 @@ 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)
 {
 	struct zfcp_adapter *adapter = (struct zfcp_adapter *) data;
-	struct list_head *next;
 	struct zfcp_erp_action *act;
 	unsigned long flags;
 
@@ -1406,12 +1618,11 @@ static int zfcp_erp_thread(void *data)
 			break;
 
 		write_lock_irqsave(&adapter->erp_lock, flags);
-		next = adapter->erp_ready_head.next;
+		act = list_first_entry_or_null(&adapter->erp_ready_head,
+					       struct zfcp_erp_action, list);
 		write_unlock_irqrestore(&adapter->erp_lock, flags);
 
-		if (next != &adapter->erp_ready_head) {
-			act = list_entry(next, struct zfcp_erp_action, list);
-
+		if (act) {
 			/* there is more to come after dismission, no notify */
 			if (zfcp_erp_strategy(act) != ZFCP_ERP_DISMISSED)
 				zfcp_erp_wakeup(adapter);
@@ -1425,7 +1636,7 @@ static int zfcp_erp_thread(void *data)
  * zfcp_erp_thread_setup - Start ERP thread for adapter
  * @adapter: Adapter to start the ERP thread for
  *
- * Returns 0 on success or error code from kernel_thread()
+ * Return: 0 on success, or error code from kthread_run().
  */
 int zfcp_erp_thread_setup(struct zfcp_adapter *adapter)
 {
@@ -1495,6 +1706,13 @@ void zfcp_erp_set_adapter_status(struct zfcp_adapter *adapter, u32 mask)
 		atomic_or(common_mask, &port->status);
 	read_unlock_irqrestore(&adapter->port_list_lock, flags);
 
+	/*
+	 * if `scsi_host` is missing, xconfig/xport data has never completed
+	 * yet, so we can't access it, but there are also no SDEVs yet
+	 */
+	if (adapter->scsi_host == NULL)
+		return;
+
 	spin_lock_irqsave(adapter->scsi_host->host_lock, flags);
 	__shost_for_each_device(sdev, adapter->scsi_host)
 		atomic_or(common_mask, &sdev_to_zfcp(sdev)->status);
@@ -1532,6 +1750,13 @@ void zfcp_erp_clear_adapter_status(struct zfcp_adapter *adapter, u32 mask)
 	}
 	read_unlock_irqrestore(&adapter->port_list_lock, flags);
 
+	/*
+	 * if `scsi_host` is missing, xconfig/xport data has never completed
+	 * yet, so we can't access it, but there are also no SDEVs yet
+	 */
+	if (adapter->scsi_host == NULL)
+		return;
+
 	spin_lock_irqsave(adapter->scsi_host->host_lock, flags);
 	__shost_for_each_device(sdev, adapter->scsi_host) {
 		atomic_andnot(common_mask, &sdev_to_zfcp(sdev)->status);
@@ -1627,3 +1852,14 @@ void zfcp_erp_clear_lun_status(struct scsi_device *sdev, u32 mask)
 		atomic_set(&zfcp_sdev->erp_counter, 0);
 }
 
+/**
+ * zfcp_erp_adapter_reset_sync() - Really reopen adapter and wait.
+ * @adapter: Pointer to zfcp_adapter to reopen.
+ * @dbftag: Trace tag string of length %ZFCP_DBF_TAG_LEN.
+ */
+void zfcp_erp_adapter_reset_sync(struct zfcp_adapter *adapter, char *dbftag)
+{
+	zfcp_erp_set_adapter_status(adapter, ZFCP_STATUS_COMMON_RUNNING);
+	zfcp_erp_adapter_reopen(adapter, ZFCP_STATUS_COMMON_ERP_FAILED, dbftag);
+	zfcp_erp_wait(adapter);
+}