Example #1
0
/**
 * zfcp_status_read_refill - refill the long running status_read_requests
 * @adapter: ptr to struct zfcp_adapter for which the buffers should be refilled
 *
 * Returns: 0 on success, 1 otherwise
 *
 * if there are 16 or more status_read requests missing an adapter_reopen
 * is triggered
 */
int zfcp_status_read_refill(struct zfcp_adapter *adapter)
{
	while (atomic_read(&adapter->stat_miss) > 0)
		if (zfcp_fsf_status_read(adapter->qdio)) {
			if (atomic_read(&adapter->stat_miss) >=
			    adapter->stat_read_buf_num) {
				zfcp_erp_adapter_reopen(adapter, 0, "axsref1");
				return 1;
			}
			break;
		} else
			atomic_dec(&adapter->stat_miss);
	return 0;
}
static int zfcp_scsi_eh_host_reset_handler(struct scsi_cmnd *scpnt)
{
	struct zfcp_scsi_dev *zfcp_sdev = sdev_to_zfcp(scpnt->device);
	struct zfcp_adapter *adapter = zfcp_sdev->port->adapter;
	int ret;

	zfcp_erp_adapter_reopen(adapter, 0, "schrh_1");
	zfcp_erp_wait(adapter);
	ret = fc_block_scsi_eh(scpnt);
	if (ret)
		return ret;

	return SUCCESS;
}
Example #3
0
static void zfcp_qdio_int_resp(struct ccw_device *cdev, unsigned int qdio_err,
			       int queue_no, int idx, int count,
			       unsigned long parm)
{
	struct zfcp_qdio *qdio = (struct zfcp_qdio *) parm;
	struct zfcp_adapter *adapter = qdio->adapter;
	int sbal_no, sbal_idx;

	if (unlikely(qdio_err)) {
		if (zfcp_adapter_multi_buffer_active(adapter)) {
			void *pl[ZFCP_QDIO_MAX_SBALS_PER_REQ + 1];
			struct qdio_buffer_element *sbale;
			u64 req_id;
			u8 scount;

			memset(pl, 0,
			       ZFCP_QDIO_MAX_SBALS_PER_REQ * sizeof(void *));
			sbale = qdio->res_q[idx]->element;
			req_id = (u64) sbale->addr;
			scount = min(sbale->scount + 1,
				     ZFCP_QDIO_MAX_SBALS_PER_REQ + 1);
				     /* incl. signaling SBAL */

			for (sbal_no = 0; sbal_no < scount; sbal_no++) {
				sbal_idx = (idx + sbal_no) %
					QDIO_MAX_BUFFERS_PER_Q;
				pl[sbal_no] = qdio->res_q[sbal_idx];
			}
			zfcp_dbf_hba_def_err(adapter, req_id, scount, pl);
		}
		zfcp_qdio_handler_error(qdio, "qdires1", qdio_err);
		return;
	}

	/*
	 * go through all SBALs from input queue currently
	 * returned by QDIO layer
	 */
	for (sbal_no = 0; sbal_no < count; sbal_no++) {
		sbal_idx = (idx + sbal_no) % QDIO_MAX_BUFFERS_PER_Q;
		/* go through all SBALEs of SBAL */
		zfcp_fsf_reqid_check(qdio, sbal_idx);
	}

	/*
	 * put SBALs back to response queue
	 */
	if (do_QDIO(cdev, QDIO_FLAG_SYNC_INPUT, 0, idx, count))
		zfcp_erp_adapter_reopen(qdio->adapter, 0, "qdires2");
}
Example #4
0
static void zfcp_qdio_handler_error(struct zfcp_qdio *qdio, char *id,
				    unsigned int qdio_err)
{
	struct zfcp_adapter *adapter = qdio->adapter;

	dev_warn(&adapter->ccw_device->dev, "A QDIO problem occurred\n");

	if (qdio_err & QDIO_ERROR_SLSB_STATE) {
		zfcp_qdio_siosl(adapter);
		zfcp_erp_adapter_shutdown(adapter, 0, id);
		return;
	}
	zfcp_erp_adapter_reopen(adapter,
				ZFCP_STATUS_ADAPTER_LINK_UNPLUGGED |
				ZFCP_STATUS_COMMON_ERP_FAILED, id);
}
Example #5
0
/**
 * zfcp_qdio_sbal_get - get free sbal in request queue, wait if necessary
 * @qdio: pointer to struct zfcp_qdio
 *
 * The req_q_lock must be held by the caller of this function, and
 * this function may only be called from process context; it will
 * sleep when waiting for a free sbal.
 *
 * Returns: 0 on success, -EIO if there is no free sbal after waiting.
 */
int zfcp_qdio_sbal_get(struct zfcp_qdio *qdio)
{
	long ret;

	ret = wait_event_interruptible_lock_irq_timeout(qdio->req_q_wq,
		       zfcp_qdio_sbal_check(qdio), qdio->req_q_lock, 5 * HZ);

	if (!(atomic_read(&qdio->adapter->status) & ZFCP_STATUS_ADAPTER_QDIOUP))
		return -EIO;

	if (ret > 0)
		return 0;

	if (!ret) {
		atomic_inc(&qdio->req_q_full);
		/* assume hanging outbound queue, try queue recovery */
		zfcp_erp_adapter_reopen(qdio->adapter, 0, "qdsbg_1");
	}

	return -EIO;
}
Example #6
0
static void zfcp_scsi_forget_cmnds(struct zfcp_scsi_dev *zsdev, u8 tm_flags)
{
	struct zfcp_adapter *adapter = zsdev->port->adapter;
	struct zfcp_scsi_req_filter filter = {
		.tmf_scope = FCP_TMF_TGT_RESET,
		.port_handle = zsdev->port->handle,
	};
	unsigned long flags;

	if (tm_flags == FCP_TMF_LUN_RESET) {
		filter.tmf_scope = FCP_TMF_LUN_RESET;
		filter.lun_handle = zsdev->lun_handle;
	}

	/*
	 * abort_lock secures against other processings - in the abort-function
	 * and normal cmnd-handler - of (struct zfcp_fsf_req *)->data
	 */
	write_lock_irqsave(&adapter->abort_lock, flags);
	zfcp_reqlist_apply_for_all(adapter->req_list, zfcp_scsi_forget_cmnd,
				   &filter);
	write_unlock_irqrestore(&adapter->abort_lock, flags);
}

/**
 * zfcp_scsi_task_mgmt_function() - Send a task management function (sync).
 * @sdev: Pointer to SCSI device to send the task management command to.
 * @tm_flags: Task management flags,
 *	      here we only handle %FCP_TMF_TGT_RESET or %FCP_TMF_LUN_RESET.
 */
static int zfcp_scsi_task_mgmt_function(struct scsi_device *sdev, u8 tm_flags)
{
	struct zfcp_scsi_dev *zfcp_sdev = sdev_to_zfcp(sdev);
	struct zfcp_adapter *adapter = zfcp_sdev->port->adapter;
	struct fc_rport *rport = starget_to_rport(scsi_target(sdev));
	struct zfcp_fsf_req *fsf_req = NULL;
	int retval = SUCCESS, ret;
	int retry = 3;

	while (retry--) {
		fsf_req = zfcp_fsf_fcp_task_mgmt(sdev, tm_flags);
		if (fsf_req)
			break;

		zfcp_dbf_scsi_devreset("wait", sdev, tm_flags, NULL);
		zfcp_erp_wait(adapter);
		ret = fc_block_rport(rport);
		if (ret) {
			zfcp_dbf_scsi_devreset("fiof", sdev, tm_flags, NULL);
			return ret;
		}

		if (!(atomic_read(&adapter->status) &
		      ZFCP_STATUS_COMMON_RUNNING)) {
			zfcp_dbf_scsi_devreset("nres", sdev, tm_flags, NULL);
			return SUCCESS;
		}
	}
	if (!fsf_req) {
		zfcp_dbf_scsi_devreset("reqf", sdev, tm_flags, NULL);
		return FAILED;
	}

	wait_for_completion(&fsf_req->completion);

	if (fsf_req->status & ZFCP_STATUS_FSFREQ_TMFUNCFAILED) {
		zfcp_dbf_scsi_devreset("fail", sdev, tm_flags, fsf_req);
		retval = FAILED;
	} else {
		zfcp_dbf_scsi_devreset("okay", sdev, tm_flags, fsf_req);
		zfcp_scsi_forget_cmnds(zfcp_sdev, tm_flags);
	}

	zfcp_fsf_req_free(fsf_req);
	return retval;
}

static int zfcp_scsi_eh_device_reset_handler(struct scsi_cmnd *scpnt)
{
	struct scsi_device *sdev = scpnt->device;

	return zfcp_scsi_task_mgmt_function(sdev, FCP_TMF_LUN_RESET);
}

static int zfcp_scsi_eh_target_reset_handler(struct scsi_cmnd *scpnt)
{
	struct scsi_target *starget = scsi_target(scpnt->device);
	struct fc_rport *rport = starget_to_rport(starget);
	struct Scsi_Host *shost = rport_to_shost(rport);
	struct scsi_device *sdev = NULL, *tmp_sdev;
	struct zfcp_adapter *adapter =
		(struct zfcp_adapter *)shost->hostdata[0];
	int ret;

	shost_for_each_device(tmp_sdev, shost) {
		if (tmp_sdev->id == starget->id) {
			sdev = tmp_sdev;
			break;
		}
	}
	if (!sdev) {
		ret = FAILED;
		zfcp_dbf_scsi_eh("tr_nosd", adapter, starget->id, ret);
		return ret;
	}

	ret = zfcp_scsi_task_mgmt_function(sdev, FCP_TMF_TGT_RESET);

	/* release reference from above shost_for_each_device */
	if (sdev)
		scsi_device_put(tmp_sdev);

	return ret;
}

static int zfcp_scsi_eh_host_reset_handler(struct scsi_cmnd *scpnt)
{
	struct zfcp_scsi_dev *zfcp_sdev = sdev_to_zfcp(scpnt->device);
	struct zfcp_adapter *adapter = zfcp_sdev->port->adapter;
	int ret = SUCCESS, fc_ret;

	zfcp_erp_adapter_reopen(adapter, 0, "schrh_1");
	zfcp_erp_wait(adapter);
	fc_ret = fc_block_scsi_eh(scpnt);
	if (fc_ret)
		ret = fc_ret;

	zfcp_dbf_scsi_eh("schrh_r", adapter, ~0, ret);
	return ret;
}

/**
 * zfcp_scsi_sysfs_host_reset() - Support scsi_host sysfs attribute host_reset.
 * @shost: Pointer to Scsi_Host to perform action on.
 * @reset_type: We support %SCSI_ADAPTER_RESET but not %SCSI_FIRMWARE_RESET.
 *
 * Return: 0 on %SCSI_ADAPTER_RESET, -%EOPNOTSUPP otherwise.
 *
 * This is similar to zfcp_sysfs_adapter_failed_store().
 */
static int zfcp_scsi_sysfs_host_reset(struct Scsi_Host *shost, int reset_type)
{
	struct zfcp_adapter *adapter =
		(struct zfcp_adapter *)shost->hostdata[0];
	int ret = 0;

	if (reset_type != SCSI_ADAPTER_RESET) {
		ret = -EOPNOTSUPP;
		zfcp_dbf_scsi_eh("scshr_n", adapter, ~0, ret);
		return ret;
	}

	zfcp_erp_adapter_reset_sync(adapter, "scshr_y");
	return ret;
}

struct scsi_transport_template *zfcp_scsi_transport_template;

static struct scsi_host_template zfcp_scsi_host_template = {
	.module			 = THIS_MODULE,
	.name			 = "zfcp",
	.queuecommand		 = zfcp_scsi_queuecommand,
	.eh_timed_out		 = fc_eh_timed_out,
	.eh_abort_handler	 = zfcp_scsi_eh_abort_handler,
	.eh_device_reset_handler = zfcp_scsi_eh_device_reset_handler,
	.eh_target_reset_handler = zfcp_scsi_eh_target_reset_handler,
	.eh_host_reset_handler	 = zfcp_scsi_eh_host_reset_handler,
	.slave_alloc		 = zfcp_scsi_slave_alloc,
	.slave_configure	 = zfcp_scsi_slave_configure,
	.slave_destroy		 = zfcp_scsi_slave_destroy,
	.change_queue_depth	 = scsi_change_queue_depth,
	.host_reset		 = zfcp_scsi_sysfs_host_reset,
	.proc_name		 = "zfcp",
	.can_queue		 = 4096,
	.this_id		 = -1,
	.sg_tablesize		 = (((QDIO_MAX_ELEMENTS_PER_BUFFER - 1)
				     * ZFCP_QDIO_MAX_SBALS_PER_REQ) - 2),
				   /* GCD, adjusted later */
	.max_sectors		 = (((QDIO_MAX_ELEMENTS_PER_BUFFER - 1)
				     * ZFCP_QDIO_MAX_SBALS_PER_REQ) - 2) * 8,
				   /* GCD, adjusted later */
	/* report size limit per scatter-gather segment */
	.max_segment_size	 = ZFCP_QDIO_SBALE_LEN,
	.dma_boundary		 = ZFCP_QDIO_SBALE_LEN - 1,
	.shost_attrs		 = zfcp_sysfs_shost_attrs,
	.sdev_attrs		 = zfcp_sysfs_sdev_attrs,
	.track_queue_depth	 = 1,
	.supported_mode		 = MODE_INITIATOR,
};

/**
 * zfcp_scsi_adapter_register - Register SCSI and FC host with SCSI midlayer
 * @adapter: The zfcp adapter to register with the SCSI midlayer
 */
int zfcp_scsi_adapter_register(struct zfcp_adapter *adapter)
{
	struct ccw_dev_id dev_id;

	if (adapter->scsi_host)
		return 0;

	ccw_device_get_id(adapter->ccw_device, &dev_id);
	/* register adapter as SCSI host with mid layer of SCSI stack */
	adapter->scsi_host = scsi_host_alloc(&zfcp_scsi_host_template,
					     sizeof (struct zfcp_adapter *));
	if (!adapter->scsi_host) {
		dev_err(&adapter->ccw_device->dev,
			"Registering the FCP device with the "
			"SCSI stack failed\n");
		return -EIO;
	}

	/* tell the SCSI stack some characteristics of this adapter */
	adapter->scsi_host->max_id = 511;
	adapter->scsi_host->max_lun = 0xFFFFFFFF;
	adapter->scsi_host->max_channel = 0;
	adapter->scsi_host->unique_id = dev_id.devno;
	adapter->scsi_host->max_cmd_len = 16; /* in struct fcp_cmnd */
	adapter->scsi_host->transportt = zfcp_scsi_transport_template;

	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);
		return -EIO;
	}

	return 0;
}

/**
 * zfcp_scsi_adapter_unregister - Unregister SCSI and FC host from SCSI midlayer
 * @adapter: The zfcp adapter to unregister.
 */
void zfcp_scsi_adapter_unregister(struct zfcp_adapter *adapter)
{
	struct Scsi_Host *shost;
	struct zfcp_port *port;

	shost = adapter->scsi_host;
	if (!shost)
		return;

	read_lock_irq(&adapter->port_list_lock);
	list_for_each_entry(port, &adapter->port_list, list)
		port->rport = NULL;
	read_unlock_irq(&adapter->port_list_lock);

	fc_remove_host(shost);
	scsi_remove_host(shost);
	scsi_host_put(shost);
	adapter->scsi_host = NULL;
}

static struct fc_host_statistics*
zfcp_scsi_init_fc_host_stats(struct zfcp_adapter *adapter)
{
	struct fc_host_statistics *fc_stats;

	if (!adapter->fc_stats) {
		fc_stats = kmalloc(sizeof(*fc_stats), GFP_KERNEL);
		if (!fc_stats)
			return NULL;
		adapter->fc_stats = fc_stats; /* freed in adapter_release */
	}
	memset(adapter->fc_stats, 0, sizeof(*adapter->fc_stats));
	return adapter->fc_stats;
}

static void zfcp_scsi_adjust_fc_host_stats(struct fc_host_statistics *fc_stats,
					   struct fsf_qtcb_bottom_port *data,
					   struct fsf_qtcb_bottom_port *old)
{
	fc_stats->seconds_since_last_reset =
		data->seconds_since_last_reset - old->seconds_since_last_reset;
	fc_stats->tx_frames = data->tx_frames - old->tx_frames;
	fc_stats->tx_words = data->tx_words - old->tx_words;
	fc_stats->rx_frames = data->rx_frames - old->rx_frames;
	fc_stats->rx_words = data->rx_words - old->rx_words;
	fc_stats->lip_count = data->lip - old->lip;
	fc_stats->nos_count = data->nos - old->nos;
	fc_stats->error_frames = data->error_frames - old->error_frames;
	fc_stats->dumped_frames = data->dumped_frames - old->dumped_frames;
	fc_stats->link_failure_count = data->link_failure - old->link_failure;
	fc_stats->loss_of_sync_count = data->loss_of_sync - old->loss_of_sync;
	fc_stats->loss_of_signal_count =
		data->loss_of_signal - old->loss_of_signal;
	fc_stats->prim_seq_protocol_err_count =
		data->psp_error_counts - old->psp_error_counts;
	fc_stats->invalid_tx_word_count =
		data->invalid_tx_words - old->invalid_tx_words;
	fc_stats->invalid_crc_count = data->invalid_crcs - old->invalid_crcs;
	fc_stats->fcp_input_requests =
		data->input_requests - old->input_requests;
	fc_stats->fcp_output_requests =
		data->output_requests - old->output_requests;
	fc_stats->fcp_control_requests =
		data->control_requests - old->control_requests;
	fc_stats->fcp_input_megabytes = data->input_mb - old->input_mb;
	fc_stats->fcp_output_megabytes = data->output_mb - old->output_mb;
}

static void zfcp_scsi_set_fc_host_stats(struct fc_host_statistics *fc_stats,
					struct fsf_qtcb_bottom_port *data)
{
	fc_stats->seconds_since_last_reset = data->seconds_since_last_reset;
	fc_stats->tx_frames = data->tx_frames;
	fc_stats->tx_words = data->tx_words;
	fc_stats->rx_frames = data->rx_frames;
	fc_stats->rx_words = data->rx_words;
	fc_stats->lip_count = data->lip;
	fc_stats->nos_count = data->nos;
	fc_stats->error_frames = data->error_frames;
	fc_stats->dumped_frames = data->dumped_frames;
	fc_stats->link_failure_count = data->link_failure;
	fc_stats->loss_of_sync_count = data->loss_of_sync;
	fc_stats->loss_of_signal_count = data->loss_of_signal;
	fc_stats->prim_seq_protocol_err_count = data->psp_error_counts;
	fc_stats->invalid_tx_word_count = data->invalid_tx_words;
	fc_stats->invalid_crc_count = data->invalid_crcs;
	fc_stats->fcp_input_requests = data->input_requests;
	fc_stats->fcp_output_requests = data->output_requests;
	fc_stats->fcp_control_requests = data->control_requests;
	fc_stats->fcp_input_megabytes = data->input_mb;
	fc_stats->fcp_output_megabytes = data->output_mb;
}
Example #7
0
/**
 * zfcp_erp_adapter_shutdown - Shutdown adapter.
 * @adapter: Adapter to shut down.
 * @clear: Status flags to clear.
 * @id: Id for debug trace event.
 * @ref: Reference for debug trace event.
 */
void zfcp_erp_adapter_shutdown(struct zfcp_adapter *adapter, int clear,
			       char *id, void *ref)
{
	int flags = ZFCP_STATUS_COMMON_RUNNING | ZFCP_STATUS_COMMON_ERP_FAILED;
	zfcp_erp_adapter_reopen(adapter, clear | flags, id, ref);
}
Example #8
0
/*
 * function:   	zfcp_qdio_handler_error_check
 *
 * purpose:     called by the response handler to determine error condition
 *
 * returns:	error flag
 *
 */
static inline int
zfcp_qdio_handler_error_check(struct zfcp_adapter *adapter,
			      unsigned int status,
			      unsigned int qdio_error, unsigned int siga_error)
{
	int retval = 0;

	if (ZFCP_LOG_CHECK(ZFCP_LOG_LEVEL_TRACE)) {
		if (status & QDIO_STATUS_INBOUND_INT) {
			ZFCP_LOG_TRACE("status is"
				       " QDIO_STATUS_INBOUND_INT \n");
		}
		if (status & QDIO_STATUS_OUTBOUND_INT) {
			ZFCP_LOG_TRACE("status is"
				       " QDIO_STATUS_OUTBOUND_INT \n");
		}
	}			// if (ZFCP_LOG_CHECK(ZFCP_LOG_LEVEL_TRACE))
	if (unlikely(status & QDIO_STATUS_LOOK_FOR_ERROR)) {
		retval = -EIO;

		ZFCP_LOG_FLAGS(1, "QDIO_STATUS_LOOK_FOR_ERROR \n");

		ZFCP_LOG_INFO("QDIO problem occurred (status=0x%x, "
			      "qdio_error=0x%x, siga_error=0x%x)\n",
			      status, qdio_error, siga_error);

		if (status & QDIO_STATUS_ACTIVATE_CHECK_CONDITION) {
			ZFCP_LOG_FLAGS(2,
				       "QDIO_STATUS_ACTIVATE_CHECK_CONDITION\n");
		}
		if (status & QDIO_STATUS_MORE_THAN_ONE_QDIO_ERROR) {
			ZFCP_LOG_FLAGS(2,
				       "QDIO_STATUS_MORE_THAN_ONE_QDIO_ERROR\n");
		}
		if (status & QDIO_STATUS_MORE_THAN_ONE_SIGA_ERROR) {
			ZFCP_LOG_FLAGS(2,
				       "QDIO_STATUS_MORE_THAN_ONE_SIGA_ERROR\n");
		}

		if (siga_error & QDIO_SIGA_ERROR_ACCESS_EXCEPTION) {
			ZFCP_LOG_FLAGS(2, "QDIO_SIGA_ERROR_ACCESS_EXCEPTION\n");
		}

		if (siga_error & QDIO_SIGA_ERROR_B_BIT_SET) {
			ZFCP_LOG_FLAGS(2, "QDIO_SIGA_ERROR_B_BIT_SET\n");
		}

		switch (qdio_error) {
		case 0:
			ZFCP_LOG_FLAGS(3, "QDIO_OK");
			break;
		case SLSB_P_INPUT_ERROR:
			ZFCP_LOG_FLAGS(1, "SLSB_P_INPUT_ERROR\n");
			break;
		case SLSB_P_OUTPUT_ERROR:
			ZFCP_LOG_FLAGS(1, "SLSB_P_OUTPUT_ERROR\n");
			break;
		default:
			ZFCP_LOG_NORMAL("bug: unknown QDIO error 0x%x\n",
					qdio_error);
			break;
		}
		/* Restarting IO on the failed adapter from scratch */
		debug_text_event(adapter->erp_dbf, 1, "qdio_err");
               /*
                * Since we have been using this adapter, it is save to assume
                * that it is not failed but recoverable. The card seems to
                * report link-up events by self-initiated queue shutdown.
                * That is why we need to clear the the link-down flag
                * which is set again in case we have missed by a mile.
                */
               zfcp_erp_adapter_reopen(
                       adapter, 
                       ZFCP_STATUS_ADAPTER_LINK_UNPLUGGED |
                       ZFCP_STATUS_COMMON_ERP_FAILED);
	}
	return retval;
}
Example #9
0
static void zfcp_scsi_forget_cmnds(struct zfcp_scsi_dev *zsdev, u8 tm_flags)
{
	struct zfcp_adapter *adapter = zsdev->port->adapter;
	struct zfcp_scsi_req_filter filter = {
		.tmf_scope = FCP_TMF_TGT_RESET,
		.port_handle = zsdev->port->handle,
	};
	unsigned long flags;

	if (tm_flags == FCP_TMF_LUN_RESET) {
		filter.tmf_scope = FCP_TMF_LUN_RESET;
		filter.lun_handle = zsdev->lun_handle;
	}

	/*
	 * abort_lock secures against other processings - in the abort-function
	 * and normal cmnd-handler - of (struct zfcp_fsf_req *)->data
	 */
	write_lock_irqsave(&adapter->abort_lock, flags);
	zfcp_reqlist_apply_for_all(adapter->req_list, zfcp_scsi_forget_cmnd,
				   &filter);
	write_unlock_irqrestore(&adapter->abort_lock, flags);
}

static int zfcp_task_mgmt_function(struct scsi_cmnd *scpnt, u8 tm_flags)
{
	struct zfcp_scsi_dev *zfcp_sdev = sdev_to_zfcp(scpnt->device);
	struct zfcp_adapter *adapter = zfcp_sdev->port->adapter;
	struct zfcp_fsf_req *fsf_req = NULL;
	int retval = SUCCESS, ret;
	int retry = 3;

	while (retry--) {
		fsf_req = zfcp_fsf_fcp_task_mgmt(scpnt, tm_flags);
		if (fsf_req)
			break;

		zfcp_erp_wait(adapter);
		ret = fc_block_scsi_eh(scpnt);
		if (ret)
			return ret;

		if (!(atomic_read(&adapter->status) &
		      ZFCP_STATUS_COMMON_RUNNING)) {
			zfcp_dbf_scsi_devreset("nres", scpnt, tm_flags);
			return SUCCESS;
		}
	}
	if (!fsf_req)
		return FAILED;

	wait_for_completion(&fsf_req->completion);

	if (fsf_req->status & ZFCP_STATUS_FSFREQ_TMFUNCFAILED) {
		zfcp_dbf_scsi_devreset("fail", scpnt, tm_flags);
		retval = FAILED;
	} else {
		zfcp_dbf_scsi_devreset("okay", scpnt, tm_flags);
		zfcp_scsi_forget_cmnds(zfcp_sdev, tm_flags);
	}

	zfcp_fsf_req_free(fsf_req);
	return retval;
}

static int zfcp_scsi_eh_device_reset_handler(struct scsi_cmnd *scpnt)
{
	return zfcp_task_mgmt_function(scpnt, FCP_TMF_LUN_RESET);
}

static int zfcp_scsi_eh_target_reset_handler(struct scsi_cmnd *scpnt)
{
	return zfcp_task_mgmt_function(scpnt, FCP_TMF_TGT_RESET);
}

static int zfcp_scsi_eh_host_reset_handler(struct scsi_cmnd *scpnt)
{
	struct zfcp_scsi_dev *zfcp_sdev = sdev_to_zfcp(scpnt->device);
	struct zfcp_adapter *adapter = zfcp_sdev->port->adapter;
	int ret;

	zfcp_erp_adapter_reopen(adapter, 0, "schrh_1");
	zfcp_erp_wait(adapter);
	ret = fc_block_scsi_eh(scpnt);
	if (ret)
		return ret;

	return SUCCESS;
}

struct scsi_transport_template *zfcp_scsi_transport_template;

static struct scsi_host_template zfcp_scsi_host_template = {
	.module			 = THIS_MODULE,
	.name			 = "zfcp",
	.queuecommand		 = zfcp_scsi_queuecommand,
	.eh_abort_handler	 = zfcp_scsi_eh_abort_handler,
	.eh_device_reset_handler = zfcp_scsi_eh_device_reset_handler,
	.eh_target_reset_handler = zfcp_scsi_eh_target_reset_handler,
	.eh_host_reset_handler	 = zfcp_scsi_eh_host_reset_handler,
	.slave_alloc		 = zfcp_scsi_slave_alloc,
	.slave_configure	 = zfcp_scsi_slave_configure,
	.slave_destroy		 = zfcp_scsi_slave_destroy,
	.change_queue_depth	 = scsi_change_queue_depth,
	.proc_name		 = "zfcp",
	.can_queue		 = 4096,
	.this_id		 = -1,
	.sg_tablesize		 = (((QDIO_MAX_ELEMENTS_PER_BUFFER - 1)
				     * ZFCP_QDIO_MAX_SBALS_PER_REQ) - 2),
				   /* GCD, adjusted later */
	.max_sectors		 = (((QDIO_MAX_ELEMENTS_PER_BUFFER - 1)
				     * ZFCP_QDIO_MAX_SBALS_PER_REQ) - 2) * 8,
				   /* GCD, adjusted later */
	.dma_boundary		 = ZFCP_QDIO_SBALE_LEN - 1,
	.use_clustering		 = 1,
	.shost_attrs		 = zfcp_sysfs_shost_attrs,
	.sdev_attrs		 = zfcp_sysfs_sdev_attrs,
	.track_queue_depth	 = 1,
};

/**
 * zfcp_scsi_adapter_register - Register SCSI and FC host with SCSI midlayer
 * @adapter: The zfcp adapter to register with the SCSI midlayer
 */
int zfcp_scsi_adapter_register(struct zfcp_adapter *adapter)
{
	struct ccw_dev_id dev_id;

	if (adapter->scsi_host)
		return 0;

	ccw_device_get_id(adapter->ccw_device, &dev_id);
	/* register adapter as SCSI host with mid layer of SCSI stack */
	adapter->scsi_host = scsi_host_alloc(&zfcp_scsi_host_template,
					     sizeof (struct zfcp_adapter *));
	if (!adapter->scsi_host) {
		dev_err(&adapter->ccw_device->dev,
			"Registering the FCP device with the "
			"SCSI stack failed\n");
		return -EIO;
	}

	/* tell the SCSI stack some characteristics of this adapter */
	adapter->scsi_host->max_id = 511;
	adapter->scsi_host->max_lun = 0xFFFFFFFF;
	adapter->scsi_host->max_channel = 0;
	adapter->scsi_host->unique_id = dev_id.devno;
	adapter->scsi_host->max_cmd_len = 16; /* in struct fcp_cmnd */
	adapter->scsi_host->transportt = zfcp_scsi_transport_template;

	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);
		return -EIO;
	}

	return 0;
}

/**
 * zfcp_scsi_adapter_unregister - Unregister SCSI and FC host from SCSI midlayer
 * @adapter: The zfcp adapter to unregister.
 */
void zfcp_scsi_adapter_unregister(struct zfcp_adapter *adapter)
{
	struct Scsi_Host *shost;
	struct zfcp_port *port;

	shost = adapter->scsi_host;
	if (!shost)
		return;

	read_lock_irq(&adapter->port_list_lock);
	list_for_each_entry(port, &adapter->port_list, list)
		port->rport = NULL;
	read_unlock_irq(&adapter->port_list_lock);

	fc_remove_host(shost);
	scsi_remove_host(shost);
	scsi_host_put(shost);
	adapter->scsi_host = NULL;
}

static struct fc_host_statistics*
zfcp_init_fc_host_stats(struct zfcp_adapter *adapter)
{
	struct fc_host_statistics *fc_stats;

	if (!adapter->fc_stats) {
		fc_stats = kmalloc(sizeof(*fc_stats), GFP_KERNEL);
		if (!fc_stats)
			return NULL;
		adapter->fc_stats = fc_stats; /* freed in adapter_release */
	}
	memset(adapter->fc_stats, 0, sizeof(*adapter->fc_stats));
	return adapter->fc_stats;
}

static void zfcp_adjust_fc_host_stats(struct fc_host_statistics *fc_stats,
				      struct fsf_qtcb_bottom_port *data,
				      struct fsf_qtcb_bottom_port *old)
{
	fc_stats->seconds_since_last_reset =
		data->seconds_since_last_reset - old->seconds_since_last_reset;
	fc_stats->tx_frames = data->tx_frames - old->tx_frames;
	fc_stats->tx_words = data->tx_words - old->tx_words;
	fc_stats->rx_frames = data->rx_frames - old->rx_frames;
	fc_stats->rx_words = data->rx_words - old->rx_words;
	fc_stats->lip_count = data->lip - old->lip;
	fc_stats->nos_count = data->nos - old->nos;
	fc_stats->error_frames = data->error_frames - old->error_frames;
	fc_stats->dumped_frames = data->dumped_frames - old->dumped_frames;
	fc_stats->link_failure_count = data->link_failure - old->link_failure;
	fc_stats->loss_of_sync_count = data->loss_of_sync - old->loss_of_sync;
	fc_stats->loss_of_signal_count =
		data->loss_of_signal - old->loss_of_signal;
	fc_stats->prim_seq_protocol_err_count =
		data->psp_error_counts - old->psp_error_counts;
	fc_stats->invalid_tx_word_count =
		data->invalid_tx_words - old->invalid_tx_words;
	fc_stats->invalid_crc_count = data->invalid_crcs - old->invalid_crcs;
	fc_stats->fcp_input_requests =
		data->input_requests - old->input_requests;
	fc_stats->fcp_output_requests =
		data->output_requests - old->output_requests;
	fc_stats->fcp_control_requests =
		data->control_requests - old->control_requests;
	fc_stats->fcp_input_megabytes = data->input_mb - old->input_mb;
	fc_stats->fcp_output_megabytes = data->output_mb - old->output_mb;
}

static void zfcp_set_fc_host_stats(struct fc_host_statistics *fc_stats,
				   struct fsf_qtcb_bottom_port *data)
{
	fc_stats->seconds_since_last_reset = data->seconds_since_last_reset;
	fc_stats->tx_frames = data->tx_frames;
	fc_stats->tx_words = data->tx_words;
	fc_stats->rx_frames = data->rx_frames;
	fc_stats->rx_words = data->rx_words;
	fc_stats->lip_count = data->lip;
	fc_stats->nos_count = data->nos;
	fc_stats->error_frames = data->error_frames;
	fc_stats->dumped_frames = data->dumped_frames;
	fc_stats->link_failure_count = data->link_failure;
	fc_stats->loss_of_sync_count = data->loss_of_sync;
	fc_stats->loss_of_signal_count = data->loss_of_signal;
	fc_stats->prim_seq_protocol_err_count = data->psp_error_counts;
	fc_stats->invalid_tx_word_count = data->invalid_tx_words;
	fc_stats->invalid_crc_count = data->invalid_crcs;
	fc_stats->fcp_input_requests = data->input_requests;
	fc_stats->fcp_output_requests = data->output_requests;
	fc_stats->fcp_control_requests = data->control_requests;
	fc_stats->fcp_input_megabytes = data->input_mb;
	fc_stats->fcp_output_megabytes = data->output_mb;
}