zfcp_scsi.c

linux-2.6.15.6

}

/**
 * zfcp_scsi_eh_abort_handler - abort the specified SCSI command
 * @scpnt: pointer to scsi_cmnd to be aborted 
 * Return: SUCCESS - command has been aborted and cleaned up in internal
 *          bookkeeping, SCSI stack won't be called for aborted command
 *         FAILED - otherwise
 *
 * We do not need to care for a SCSI command which completes normally
 * but late during this abort routine runs.  We are allowed to return
 * late commands to the SCSI stack.  It tracks the state of commands and
 * will handle late commands.  (Usually, the normal completion of late
 * commands is ignored with respect to the running abort operation.)
 */
int
zfcp_scsi_eh_abort_handler(struct scsi_cmnd *scpnt)
{
 	struct Scsi_Host *scsi_host;
 	struct zfcp_adapter *adapter;
	struct zfcp_unit *unit;
	int retval = SUCCESS;
	struct zfcp_fsf_req *new_fsf_req = NULL;
	struct zfcp_fsf_req *old_fsf_req;
	unsigned long flags;

	scsi_host = scpnt->device->host;
	adapter = (struct zfcp_adapter *) scsi_host->hostdata[0];
	unit = (struct zfcp_unit *) scpnt->device->hostdata;

	ZFCP_LOG_INFO("aborting scsi_cmnd=%p on adapter %s\n",
		      scpnt, zfcp_get_busid_by_adapter(adapter));

	/* avoid race condition between late normal completion and abort */
	write_lock_irqsave(&adapter->abort_lock, flags);

	/*
	 * Check whether command has just completed and can not be aborted.
	 * Even if the command has just been completed late, we can access
	 * scpnt since the SCSI stack does not release it at least until
	 * this routine returns. (scpnt is parameter passed to this routine
	 * and must not disappear during abort even on late completion.)
	 */
	old_fsf_req = (struct zfcp_fsf_req *) scpnt->host_scribble;
	if (!old_fsf_req) {
		write_unlock_irqrestore(&adapter->abort_lock, flags);
		zfcp_scsi_dbf_event_abort("lte1", adapter, scpnt, new_fsf_req);
		retval = SUCCESS;
		goto out;
	}
	old_fsf_req->data = 0;
	old_fsf_req->status |= ZFCP_STATUS_FSFREQ_ABORTING;

	/* don't access old_fsf_req after releasing the abort_lock */
	write_unlock_irqrestore(&adapter->abort_lock, flags);
	/* call FSF routine which does the abort */
	new_fsf_req = zfcp_fsf_abort_fcp_command((unsigned long) old_fsf_req,
						 adapter, unit, 0);
	if (!new_fsf_req) {
		ZFCP_LOG_INFO("error: initiation of Abort FCP Cmnd failed\n");
		retval = FAILED;
		goto out;
	}

	/* wait for completion of abort */
	__wait_event(new_fsf_req->completion_wq,
		     new_fsf_req->status & ZFCP_STATUS_FSFREQ_COMPLETED);

	/* status should be valid since signals were not permitted */
	if (new_fsf_req->status & ZFCP_STATUS_FSFREQ_ABORTSUCCEEDED) {
		zfcp_scsi_dbf_event_abort("okay", adapter, scpnt, new_fsf_req);
		retval = SUCCESS;
	} else if (new_fsf_req->status & ZFCP_STATUS_FSFREQ_ABORTNOTNEEDED) {
		zfcp_scsi_dbf_event_abort("lte2", adapter, scpnt, new_fsf_req);
		retval = SUCCESS;
	} else {
		zfcp_scsi_dbf_event_abort("fail", adapter, scpnt, new_fsf_req);
		retval = FAILED;
	}
	zfcp_fsf_req_free(new_fsf_req);
 out:
	return retval;
}

/*
 * function:	zfcp_scsi_eh_device_reset_handler
 *
 * purpose:
 *
 * returns:
 */
int
zfcp_scsi_eh_device_reset_handler(struct scsi_cmnd *scpnt)
{
	int retval;
	struct zfcp_unit *unit = (struct zfcp_unit *) scpnt->device->hostdata;

	if (!unit) {
		ZFCP_LOG_NORMAL("bug: Tried reset for nonexistent unit\n");
		retval = SUCCESS;
		goto out;
	}
	ZFCP_LOG_NORMAL("resetting unit 0x%016Lx\n", unit->fcp_lun);

	/*
	 * If we do not know whether the unit supports 'logical unit reset'
	 * then try 'logical unit reset' and proceed with 'target reset'
	 * if 'logical unit reset' fails.
	 * If the unit is known not to support 'logical unit reset' then
	 * skip 'logical unit reset' and try 'target reset' immediately.
	 */
	if (!atomic_test_mask(ZFCP_STATUS_UNIT_NOTSUPPUNITRESET,
			      &unit->status)) {
		retval = zfcp_task_management_function(unit,
						       FCP_LOGICAL_UNIT_RESET,
						       scpnt);
		if (retval) {
			ZFCP_LOG_DEBUG("unit reset failed (unit=%p)\n", unit);
			if (retval == -ENOTSUPP)
				atomic_set_mask
				    (ZFCP_STATUS_UNIT_NOTSUPPUNITRESET,
				     &unit->status);
			/* fall through and try 'target reset' next */
		} else {
			ZFCP_LOG_DEBUG("unit reset succeeded (unit=%p)\n",
				       unit);
			/* avoid 'target reset' */
			retval = SUCCESS;
			goto out;
		}
	}
	retval = zfcp_task_management_function(unit, FCP_TARGET_RESET, scpnt);
	if (retval) {
		ZFCP_LOG_DEBUG("target reset failed (unit=%p)\n", unit);
		retval = FAILED;
	} else {
		ZFCP_LOG_DEBUG("target reset succeeded (unit=%p)\n", unit);
		retval = SUCCESS;
	}
 out:
	return retval;
}

static int
zfcp_task_management_function(struct zfcp_unit *unit, u8 tm_flags,
			      struct scsi_cmnd *scpnt)
{
	struct zfcp_adapter *adapter = unit->port->adapter;
	struct zfcp_fsf_req *fsf_req;
	int retval = 0;

	/* issue task management function */
	fsf_req = zfcp_fsf_send_fcp_command_task_management
		(adapter, unit, tm_flags, 0);
	if (!fsf_req) {
		ZFCP_LOG_INFO("error: creation of task management request "
			      "failed for unit 0x%016Lx on port 0x%016Lx on  "
			      "adapter %s\n", unit->fcp_lun, unit->port->wwpn,
			      zfcp_get_busid_by_adapter(adapter));
		zfcp_scsi_dbf_event_devreset("nres", tm_flags, unit, scpnt);
		retval = -ENOMEM;
		goto out;
	}

	__wait_event(fsf_req->completion_wq,
		     fsf_req->status & ZFCP_STATUS_FSFREQ_COMPLETED);

	/*
	 * check completion status of task management function
	 */
	if (fsf_req->status & ZFCP_STATUS_FSFREQ_TMFUNCFAILED) {
		zfcp_scsi_dbf_event_devreset("fail", tm_flags, unit, scpnt);
		retval = -EIO;
	} else if (fsf_req->status & ZFCP_STATUS_FSFREQ_TMFUNCNOTSUPP) {
		zfcp_scsi_dbf_event_devreset("nsup", tm_flags, unit, scpnt);
		retval = -ENOTSUPP;
	} else
		zfcp_scsi_dbf_event_devreset("okay", tm_flags, unit, scpnt);

	zfcp_fsf_req_free(fsf_req);
 out:
	return retval;
}

/**
 * zfcp_scsi_eh_bus_reset_handler - reset bus (reopen adapter)
 */
int
zfcp_scsi_eh_bus_reset_handler(struct scsi_cmnd *scpnt)
{
	struct zfcp_unit *unit = (struct zfcp_unit*) scpnt->device->hostdata;
	struct zfcp_adapter *adapter = unit->port->adapter;

	ZFCP_LOG_NORMAL("bus reset because of problems with "
			"unit 0x%016Lx\n", unit->fcp_lun);
	zfcp_erp_adapter_reopen(adapter, 0);
	zfcp_erp_wait(adapter);

	return SUCCESS;
}

/**
 * zfcp_scsi_eh_host_reset_handler - reset host (reopen adapter)
 */
int
zfcp_scsi_eh_host_reset_handler(struct scsi_cmnd *scpnt)
{
	struct zfcp_unit *unit = (struct zfcp_unit*) scpnt->device->hostdata;
	struct zfcp_adapter *adapter = unit->port->adapter;

	ZFCP_LOG_NORMAL("host reset because of problems with "
			"unit 0x%016Lx\n", unit->fcp_lun);
	zfcp_erp_adapter_reopen(adapter, 0);
	zfcp_erp_wait(adapter);

	return SUCCESS;
}

/*
 * function:	
 *
 * purpose:	
 *
 * returns:
 */
int
zfcp_adapter_scsi_register(struct zfcp_adapter *adapter)
{
	int retval = 0;
	static unsigned int unique_id = 0;

	/* register adapter as SCSI host with mid layer of SCSI stack */
	adapter->scsi_host = scsi_host_alloc(&zfcp_data.scsi_host_template,
					     sizeof (struct zfcp_adapter *));
	if (!adapter->scsi_host) {
		ZFCP_LOG_NORMAL("error: registration with SCSI stack failed "
				"for adapter %s ",
				zfcp_get_busid_by_adapter(adapter));
		retval = -EIO;
		goto out;
	}
	ZFCP_LOG_DEBUG("host registered, scsi_host=%p\n", adapter->scsi_host);

	/* tell the SCSI stack some characteristics of this adapter */
	adapter->scsi_host->max_id = 1;
	adapter->scsi_host->max_lun = 1;
	adapter->scsi_host->max_channel = 0;
	adapter->scsi_host->unique_id = unique_id++;	/* FIXME */
	adapter->scsi_host->max_cmd_len = ZFCP_MAX_SCSI_CMND_LENGTH;
	adapter->scsi_host->transportt = zfcp_transport_template;
	/*
	 * Reverse mapping of the host number to avoid race condition
	 */
	adapter->scsi_host_no = adapter->scsi_host->host_no;

	/*
	 * save a pointer to our own adapter data structure within
	 * hostdata field of SCSI host data structure
	 */
	adapter->scsi_host->hostdata[0] = (unsigned long) adapter;

	if (scsi_add_host(adapter->scsi_host, &adapter->ccw_device->dev)) {
		scsi_host_put(adapter->scsi_host);
		retval = -EIO;
		goto out;
	}
	atomic_set_mask(ZFCP_STATUS_ADAPTER_REGISTERED, &adapter->status);
 out:
	return retval;
}

/*
 * function:	
 *
 * purpose:	
 *
 * returns:
 */
void
zfcp_adapter_scsi_unregister(struct zfcp_adapter *adapter)
{
	struct Scsi_Host *shost;
	struct zfcp_port *port;

	shost = adapter->scsi_host;
	if (!shost)
		return;
	read_lock_irq(&zfcp_data.config_lock);
	list_for_each_entry(port, &adapter->port_list_head, list)
		if (port->rport)
			port->rport = NULL;
	read_unlock_irq(&zfcp_data.config_lock);
	fc_remove_host(shost);
	scsi_remove_host(shost);
	scsi_host_put(shost);
	adapter->scsi_host = NULL;
	adapter->scsi_host_no = 0;
	atomic_clear_mask(ZFCP_STATUS_ADAPTER_REGISTERED, &adapter->status);

	return;
}


void
zfcp_fsf_start_scsi_er_timer(struct zfcp_adapter *adapter)
{
	adapter->scsi_er_timer.function = zfcp_fsf_scsi_er_timeout_handler;
	adapter->scsi_er_timer.data = (unsigned long) adapter;
	adapter->scsi_er_timer.expires = jiffies + ZFCP_SCSI_ER_TIMEOUT;
	add_timer(&adapter->scsi_er_timer);
}

/*
 * Support functions for FC transport class
 */
static void
zfcp_get_port_id(struct scsi_target *starget)
{
	struct Scsi_Host *shost = dev_to_shost(starget->dev.parent);
	struct zfcp_adapter *adapter = (struct zfcp_adapter *)shost->hostdata[0];
	struct zfcp_port *port;
	unsigned long flags;

	read_lock_irqsave(&zfcp_data.config_lock, flags);
	port = zfcp_port_lookup(adapter, starget->channel, starget->id);
	if (port)
		fc_starget_port_id(starget) = port->d_id;
	else
		fc_starget_port_id(starget) = -1;
	read_unlock_irqrestore(&zfcp_data.config_lock, flags);
}

static void
zfcp_get_port_name(struct scsi_target *starget)
{
	struct Scsi_Host *shost = dev_to_shost(starget->dev.parent);
	struct zfcp_adapter *adapter = (struct zfcp_adapter *)shost->hostdata[0];
	struct zfcp_port *port;
	unsigned long flags;

	read_lock_irqsave(&zfcp_data.config_lock, flags);
	port = zfcp_port_lookup(adapter, starget->channel, starget->id);
	if (port)
		fc_starget_port_name(starget) = port->wwpn;
	else
		fc_starget_port_name(starget) = -1;
	read_unlock_irqrestore(&zfcp_data.config_lock, flags);
}

static void
zfcp_get_node_name(struct scsi_target *starget)
{
	struct Scsi_Host *shost = dev_to_shost(starget->dev.parent);
	struct zfcp_adapter *adapter = (struct zfcp_adapter *)shost->hostdata[0];
	struct zfcp_port *port;
	unsigned long flags;

	read_lock_irqsave(&zfcp_data.config_lock, flags);
	port = zfcp_port_lookup(adapter, starget->channel, starget->id);
	if (port)
		fc_starget_node_name(starget) = port->wwnn;
	else
		fc_starget_node_name(starget) = -1;
	read_unlock_irqrestore(&zfcp_data.config_lock, flags);
}

struct fc_function_template zfcp_transport_functions = {
	.get_starget_port_id = zfcp_get_port_id,
	.get_starget_port_name = zfcp_get_port_name,
	.get_starget_node_name = zfcp_get_node_name,
	.show_starget_port_id = 1,
	.show_starget_port_name = 1,
	.show_starget_node_name = 1,
	.show_rport_supported_classes = 1,
	.show_host_node_name = 1,
	.show_host_port_name = 1,
	.show_host_supported_classes = 1,
	.show_host_maxframe_size = 1,
	.show_host_serial_number = 1,
	.show_host_speed = 1,
	.show_host_port_id = 1,
};

/**
 * ZFCP_DEFINE_SCSI_ATTR
 * @_name:   name of show attribute
 * @_format: format string
 * @_value:  value to print
 *
 * Generates attribute for a unit.
 */
#define ZFCP_DEFINE_SCSI_ATTR(_name, _format, _value)                    \
static ssize_t zfcp_sysfs_scsi_##_name##_show(struct device *dev, struct device_attribute *attr,        \
                                              char *buf)                 \
{                                                                        \
        struct scsi_device *sdev;                                        \
        struct zfcp_unit *unit;                                          \
                                                                         \
        sdev = to_scsi_device(dev);                                      \
        unit = sdev->hostdata;                                           \
        return sprintf(buf, _format, _value);                            \
}                                                                        \
                                                                         \
static DEVICE_ATTR(_name, S_IRUGO, zfcp_sysfs_scsi_##_name##_show, NULL);

ZFCP_DEFINE_SCSI_ATTR(hba_id, "%s\n", zfcp_get_busid_by_unit(unit));
ZFCP_DEFINE_SCSI_ATTR(wwpn, "0x%016llx\n", unit->port->wwpn);
ZFCP_DEFINE_SCSI_ATTR(fcp_lun, "0x%016llx\n", unit->fcp_lun);

static struct device_attribute *zfcp_sysfs_sdev_attrs[] = {
	&dev_attr_fcp_lun,
	&dev_attr_wwpn,
	&dev_attr_hba_id,
	NULL
};

#undef ZFCP_LOG_AREA