zfcp_erp.c

linux-2.6.15.6

	kfree(send_els->resp);
	kfree(send_els);
}


/**
 * zfcp_test_link - lightweight link test procedure
 * @port: port to be tested
 *
 * Test status of a link to a remote port using the ELS command ADISC.
 */
int
zfcp_test_link(struct zfcp_port *port)
{
	int retval;

	zfcp_port_get(port);
	retval = zfcp_erp_adisc(port);
	if (retval != 0) {
		zfcp_port_put(port);
		ZFCP_LOG_NORMAL("reopen needed for port 0x%016Lx "
				"on adapter %s\n ", port->wwpn,
				zfcp_get_busid_by_port(port));
		retval = zfcp_erp_port_forced_reopen(port, 0);
		if (retval != 0) {
			ZFCP_LOG_NORMAL("reopen of remote port 0x%016Lx "
					"on adapter %s failed\n", port->wwpn,
					zfcp_get_busid_by_port(port));
			retval = -EPERM;
		}
	}

	return retval;
}


/*
 * function:	
 *
 * purpose:	called if a port failed to be opened normally
 *		initiates Forced Reopen recovery which is done
 *		asynchronously
 *
 * returns:	0	- initiated action succesfully
 *		<0	- failed to initiate action
 */
static int
zfcp_erp_port_forced_reopen_internal(struct zfcp_port *port, int clear_mask)
{
	int retval;
	struct zfcp_adapter *adapter = port->adapter;

	debug_text_event(adapter->erp_dbf, 5, "pf_ro");
	debug_event(adapter->erp_dbf, 5, &port->wwpn, sizeof (wwn_t));

	ZFCP_LOG_DEBUG("forced reopen of port 0x%016Lx on adapter %s\n",
		       port->wwpn, zfcp_get_busid_by_port(port));

	zfcp_erp_port_block(port, clear_mask);

	if (atomic_test_mask(ZFCP_STATUS_COMMON_ERP_FAILED, &port->status)) {
		ZFCP_LOG_DEBUG("skipped forced reopen of failed port 0x%016Lx "
			       "on adapter %s\n", port->wwpn,
			       zfcp_get_busid_by_port(port));
		debug_text_event(adapter->erp_dbf, 5, "pf_ro_f");
		debug_event(adapter->erp_dbf, 5, &port->wwpn, sizeof (wwn_t));
		retval = -EIO;
		goto out;
	}

	retval = zfcp_erp_action_enqueue(ZFCP_ERP_ACTION_REOPEN_PORT_FORCED,
					 port->adapter, port, NULL);

 out:
	return retval;
}

/*
 * function:	
 *
 * purpose:	Wrappper for zfcp_erp_port_forced_reopen_internal
 *              used to ensure the correct locking
 *
 * returns:	0	- initiated action succesfully
 *		<0	- failed to initiate action
 */
int
zfcp_erp_port_forced_reopen(struct zfcp_port *port, int clear_mask)
{
	int retval;
	unsigned long flags;
	struct zfcp_adapter *adapter;

	adapter = port->adapter;
	read_lock_irqsave(&zfcp_data.config_lock, flags);
	write_lock(&adapter->erp_lock);
	retval = zfcp_erp_port_forced_reopen_internal(port, clear_mask);
	write_unlock(&adapter->erp_lock);
	read_unlock_irqrestore(&zfcp_data.config_lock, flags);

	return retval;
}

/*
 * function:	
 *
 * purpose:	called if a port is to be opened
 *		initiates Reopen recovery which is done
 *		asynchronously
 *
 * returns:	0	- initiated action succesfully
 *		<0	- failed to initiate action
 */
static int
zfcp_erp_port_reopen_internal(struct zfcp_port *port, int clear_mask)
{
	int retval;
	struct zfcp_adapter *adapter = port->adapter;

	debug_text_event(adapter->erp_dbf, 5, "p_ro");
	debug_event(adapter->erp_dbf, 5, &port->wwpn, sizeof (wwn_t));

	ZFCP_LOG_DEBUG("reopen of port 0x%016Lx on adapter %s\n",
		       port->wwpn, zfcp_get_busid_by_port(port));

	zfcp_erp_port_block(port, clear_mask);

	if (atomic_test_mask(ZFCP_STATUS_COMMON_ERP_FAILED, &port->status)) {
		ZFCP_LOG_DEBUG("skipped reopen of failed port 0x%016Lx "
			       "on adapter %s\n", port->wwpn,
			       zfcp_get_busid_by_port(port));
		debug_text_event(adapter->erp_dbf, 5, "p_ro_f");
		debug_event(adapter->erp_dbf, 5, &port->wwpn, sizeof (wwn_t));
		/* ensure propagation of failed status to new devices */
		zfcp_erp_port_failed(port);
		retval = -EIO;
		goto out;
	}

	retval = zfcp_erp_action_enqueue(ZFCP_ERP_ACTION_REOPEN_PORT,
					 port->adapter, port, NULL);

 out:
	return retval;
}

/**
 * zfcp_erp_port_reopen - initiate reopen of a remote port
 * @port: port to be reopened
 * @clear_mask: specifies flags in port status to be cleared
 * Return: 0 on success, < 0 on error
 *
 * This is a wrappper function for zfcp_erp_port_reopen_internal. It ensures
 * correct locking. An error recovery task is initiated to do the reopen.
 * To wait for the completion of the reopen zfcp_erp_wait should be used.
 */
int
zfcp_erp_port_reopen(struct zfcp_port *port, int clear_mask)
{
	int retval;
	unsigned long flags;
	struct zfcp_adapter *adapter = port->adapter;

	read_lock_irqsave(&zfcp_data.config_lock, flags);
	write_lock(&adapter->erp_lock);
	retval = zfcp_erp_port_reopen_internal(port, clear_mask);
	write_unlock(&adapter->erp_lock);
	read_unlock_irqrestore(&zfcp_data.config_lock, flags);

	return retval;
}

/*
 * function:	
 *
 * purpose:	called if a unit is to be opened
 *		initiates Reopen recovery which is done
 *		asynchronously
 *
 * returns:	0	- initiated action succesfully
 *		<0	- failed to initiate action
 */
static int
zfcp_erp_unit_reopen_internal(struct zfcp_unit *unit, int clear_mask)
{
	int retval;
	struct zfcp_adapter *adapter = unit->port->adapter;

	debug_text_event(adapter->erp_dbf, 5, "u_ro");
	debug_event(adapter->erp_dbf, 5, &unit->fcp_lun, sizeof (fcp_lun_t));
	ZFCP_LOG_DEBUG("reopen of unit 0x%016Lx on port 0x%016Lx "
		       "on adapter %s\n", unit->fcp_lun,
		       unit->port->wwpn, zfcp_get_busid_by_unit(unit));

	zfcp_erp_unit_block(unit, clear_mask);

	if (atomic_test_mask(ZFCP_STATUS_COMMON_ERP_FAILED, &unit->status)) {
		ZFCP_LOG_DEBUG("skipped reopen of failed unit 0x%016Lx "
			       "on port 0x%016Lx on adapter %s\n",
			       unit->fcp_lun, unit->port->wwpn,
			       zfcp_get_busid_by_unit(unit));
		debug_text_event(adapter->erp_dbf, 5, "u_ro_f");
		debug_event(adapter->erp_dbf, 5, &unit->fcp_lun,
			    sizeof (fcp_lun_t));
		retval = -EIO;
		goto out;
	}

	retval = zfcp_erp_action_enqueue(ZFCP_ERP_ACTION_REOPEN_UNIT,
					 unit->port->adapter, unit->port, unit);
 out:
	return retval;
}

/**
 * zfcp_erp_unit_reopen - initiate reopen of a unit
 * @unit: unit to be reopened
 * @clear_mask: specifies flags in unit status to be cleared
 * Return: 0 on success, < 0 on error
 *
 * This is a wrappper for zfcp_erp_unit_reopen_internal. It ensures correct
 * locking. An error recovery task is initiated to do the reopen.
 * To wait for the completion of the reopen zfcp_erp_wait should be used.
 */
int
zfcp_erp_unit_reopen(struct zfcp_unit *unit, int clear_mask)
{
	int retval;
	unsigned long flags;
	struct zfcp_adapter *adapter;
	struct zfcp_port *port;

	port = unit->port;
	adapter = port->adapter;

	read_lock_irqsave(&zfcp_data.config_lock, flags);
	write_lock(&adapter->erp_lock);
	retval = zfcp_erp_unit_reopen_internal(unit, clear_mask);
	write_unlock(&adapter->erp_lock);
	read_unlock_irqrestore(&zfcp_data.config_lock, flags);

	return retval;
}

/*
 * function:	
 *
 * purpose:	disable I/O,
 *		return any open requests and clean them up,
 *		aim: no pending and incoming I/O
 *
 * returns:
 */
static void
zfcp_erp_adapter_block(struct zfcp_adapter *adapter, int clear_mask)
{
	debug_text_event(adapter->erp_dbf, 6, "a_bl");
	zfcp_erp_modify_adapter_status(adapter,
				       ZFCP_STATUS_COMMON_UNBLOCKED |
				       clear_mask, ZFCP_CLEAR);
}

/*
 * function:	
 *
 * purpose:	enable I/O
 *
 * returns:
 */
static void
zfcp_erp_adapter_unblock(struct zfcp_adapter *adapter)
{
	debug_text_event(adapter->erp_dbf, 6, "a_ubl");
	atomic_set_mask(ZFCP_STATUS_COMMON_UNBLOCKED, &adapter->status);
}

/*
 * function:	
 *
 * purpose:	disable I/O,
 *		return any open requests and clean them up,
 *		aim: no pending and incoming I/O
 *
 * returns:
 */
static void
zfcp_erp_port_block(struct zfcp_port *port, int clear_mask)
{
	struct zfcp_adapter *adapter = port->adapter;

	debug_text_event(adapter->erp_dbf, 6, "p_bl");
	debug_event(adapter->erp_dbf, 6, &port->wwpn, sizeof (wwn_t));
	zfcp_erp_modify_port_status(port,
				    ZFCP_STATUS_COMMON_UNBLOCKED | clear_mask,
				    ZFCP_CLEAR);
}

/*
 * function:	
 *
 * purpose:	enable I/O
 *
 * returns:
 */
static void
zfcp_erp_port_unblock(struct zfcp_port *port)
{
	struct zfcp_adapter *adapter = port->adapter;

	debug_text_event(adapter->erp_dbf, 6, "p_ubl");
	debug_event(adapter->erp_dbf, 6, &port->wwpn, sizeof (wwn_t));
	atomic_set_mask(ZFCP_STATUS_COMMON_UNBLOCKED, &port->status);
}

/*
 * function:	
 *
 * purpose:	disable I/O,
 *		return any open requests and clean them up,
 *		aim: no pending and incoming I/O
 *
 * returns:
 */
static void
zfcp_erp_unit_block(struct zfcp_unit *unit, int clear_mask)
{
	struct zfcp_adapter *adapter = unit->port->adapter;

	debug_text_event(adapter->erp_dbf, 6, "u_bl");
	debug_event(adapter->erp_dbf, 6, &unit->fcp_lun, sizeof (fcp_lun_t));
	zfcp_erp_modify_unit_status(unit,
				    ZFCP_STATUS_COMMON_UNBLOCKED | clear_mask,
				    ZFCP_CLEAR);
}

/*
 * function:	
 *
 * purpose:	enable I/O
 *
 * returns:
 */
static void
zfcp_erp_unit_unblock(struct zfcp_unit *unit)
{
	struct zfcp_adapter *adapter = unit->port->adapter;

	debug_text_event(adapter->erp_dbf, 6, "u_ubl");
	debug_event(adapter->erp_dbf, 6, &unit->fcp_lun, sizeof (fcp_lun_t));
	atomic_set_mask(ZFCP_STATUS_COMMON_UNBLOCKED, &unit->status);
}

/*
 * function:	
 *
 * purpose:	
 *
 * returns:
 */
static void
zfcp_erp_action_ready(struct zfcp_erp_action *erp_action)
{
	struct zfcp_adapter *adapter = erp_action->adapter;

	debug_text_event(adapter->erp_dbf, 4, "a_ar");
	debug_event(adapter->erp_dbf, 4, &erp_action->action, sizeof (int));

	zfcp_erp_action_to_ready(erp_action);
	up(&adapter->erp_ready_sem);
}

/*
 * function:	
 *
 * purpose:
 *
 * returns:	<0			erp_action not found in any list
 *		ZFCP_ERP_ACTION_READY	erp_action is in ready list
 *		ZFCP_ERP_ACTION_RUNNING	erp_action is in running list
 *
 * locks:	erp_lock must be held
 */
static int
zfcp_erp_action_exists(struct zfcp_erp_action *erp_action)
{
	int retval = -EINVAL;
	struct list_head *entry;
	struct zfcp_erp_action *entry_erp_action;
	struct zfcp_adapter *adapter = erp_action->adapter;

	/* search in running list */
	list_for_each(entry, &adapter->erp_running_head) {
		entry_erp_action =
		    list_entry(entry, struct zfcp_erp_action, list);
		if (entry_erp_action == erp_action) {
			retval = ZFCP_ERP_ACTION_RUNNING;
			goto out;
		}
	}
	/* search in ready list */
	list_for_each(entry, &adapter->erp_ready_head) {
		entry_erp_action =
		    list_entry(entry, struct zfcp_erp_action, list);
		if (entry_erp_action == erp_action) {
			retval = ZFCP_ERP_ACTION_READY;
			goto out;
		}
	}

 out:
	return retval;
}

/*
 * purpose:	checks current status of action (timed out, dismissed, ...)
 *		and does appropriate preparations (dismiss fsf request, ...)
 *
 * locks:	called under erp_lock (disabled interrupts)
 *
 * returns:	0
 */
static int
zfcp_erp_strategy_check_fsfreq(struct zfcp_erp_action *erp_action)
{
	int retval = 0;
	struct zfcp_fsf_req *fsf_req = NULL;
	struct zfcp_adapter *adapter = erp_action->adapter;

	if (erp_action->fsf_req) {
		/* take lock to ensure that request is not being deleted meanwhile */
		spin_lock(&adapter->fsf_req_list_lock);
		/* check whether fsf req does still exist */
		list_for_each_entry(fsf_req, &adapter->fsf_req_list_head, list)
		    if (fsf_req == erp_action->fsf_req)
			break;
		if (fsf_req && (fsf_req->erp_action == erp_action)) {
			/* fsf_req still exists */
			debug_text_event(adapter->erp_dbf, 3, "a_ca_req");
			debug_event(adapter->erp_dbf, 3, &fsf_req,
				    sizeof (unsigned long));
			/* dismiss fsf_req of timed out or dismissed erp_action */
			if (erp_action->status & (ZFCP_STATUS_ERP_DISMISSED |
						  ZFCP_STATUS_ERP_TIMEDOUT)) {
				debug_text_event(adapter->erp_dbf, 3,
						 "a_ca_disreq");
				fsf_req->status |= ZFCP_STATUS_FSFREQ_DISMISSED;
			}
			if (erp_action->status & ZFCP_STATUS_ERP_TIMEDOUT) {
				ZFCP_LOG_NORMAL("error: erp step timed out "
						"(action=%d, fsf_req=%p)\n ",
						erp_action->action,
						erp_action->fsf_req);
			}
			/*
			 * If fsf_req is neither dismissed nor completed
			 * then keep it running asynchronously and don't mess
			 * with the association of erp_action and fsf_req.
			 */
			if (fsf_req->status & (ZFCP_STATUS_FSFREQ_COMPLETED |
					       ZFCP_STATUS_FSFREQ_DISMISSED)) {
				/* forget about association between fsf_req
				   and erp_action */
				fsf_req->erp_action = NULL;
				erp_action->fsf_req = NULL;