linux/drivers/scsi/isci/task.h

/*
 * This file is provided under a dual BSD/GPLv2 license.  When using or
 * redistributing this file, you may do so under either license.
 *
 * GPL LICENSE SUMMARY
 *
 * Copyright(c) 2008 - 2011 Intel Corporation. All rights reserved.
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of version 2 of the GNU General Public License as
 * published by the Free Software Foundation.
 *
 * This program is distributed in the hope that it will be useful, but
 * WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin St - Fifth Floor, Boston, MA 02110-1301 USA.
 * The full GNU General Public License is included in this distribution
 * in the file called LICENSE.GPL.
 *
 * BSD LICENSE
 *
 * Copyright(c) 2008 - 2011 Intel Corporation. All rights reserved.
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 *   * Redistributions of source code must retain the above copyright
 *     notice, this list of conditions and the following disclaimer.
 *   * Redistributions in binary form must reproduce the above copyright
 *     notice, this list of conditions and the following disclaimer in
 *     the documentation and/or other materials provided with the
 *     distribution.
 *   * Neither the name of Intel Corporation nor the names of its
 *     contributors may be used to endorse or promote products derived
 *     from this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */
#ifndef _ISCI_TASK_H_
#define _ISCI_TASK_H_

#include <scsi/sas_ata.h>
#include "host.h"

#define ISCI_TERMINATION_TIMEOUT_MSEC 500

struct isci_request;

/**
 * enum isci_tmf_cb_state - This enum defines the possible states in which the
 *    TMF callback function is invoked during the TMF execution process.
 *
 *
 */
enum isci_tmf_cb_state {

	isci_tmf_init_state = 0,
	isci_tmf_started,
	isci_tmf_timed_out
};

/**
 * enum isci_tmf_function_codes - This enum defines the possible preparations
 *    of task management requests.
 *
 *
 */
enum isci_tmf_function_codes {

	isci_tmf_func_none      = 0,
	isci_tmf_ssp_task_abort = TMF_ABORT_TASK,
	isci_tmf_ssp_lun_reset  = TMF_LU_RESET,
	isci_tmf_sata_srst_high = TMF_LU_RESET + 0x100, /* Non SCSI */
	isci_tmf_sata_srst_low  = TMF_LU_RESET + 0x101  /* Non SCSI */
};
/**
 * struct isci_tmf - This class represents the task management object which
 *    acts as an interface to libsas for processing task management requests
 *
 *
 */
struct isci_tmf {

	struct completion *complete;
	enum sas_protocol proto;
	union {
		struct ssp_response_iu resp_iu;
		struct dev_to_host_fis d2h_fis;
		u8 rsp_buf[SSP_RESP_IU_MAX_SIZE];
	} resp;
	unsigned char lun[8];
	u16 io_tag;
	struct isci_remote_device *device;
	enum isci_tmf_function_codes tmf_code;
	int status;

	/* The optional callback function allows the user process to
	 * track the TMF transmit / timeout conditions.
	 */
	void (*cb_state_func)(
		enum isci_tmf_cb_state,
		struct isci_tmf *, void *);
	void *cb_data;

};

static inline void isci_print_tmf(struct isci_tmf *tmf)
{
	if (SAS_PROTOCOL_SATA == tmf->proto)
		dev_dbg(&tmf->device->isci_port->isci_host->pdev->dev,
			"%s: status = %x\n"
			"tmf->resp.d2h_fis.status = %x\n"
			"tmf->resp.d2h_fis.error = %x\n",
			__func__,
			tmf->status,
			tmf->resp.d2h_fis.status,
			tmf->resp.d2h_fis.error);
	else
		dev_dbg(&tmf->device->isci_port->isci_host->pdev->dev,
			"%s: status = %x\n"
			"tmf->resp.resp_iu.data_present = %x\n"
			"tmf->resp.resp_iu.status = %x\n"
			"tmf->resp.resp_iu.data_length = %x\n"
			"tmf->resp.resp_iu.data[0] = %x\n"
			"tmf->resp.resp_iu.data[1] = %x\n"
			"tmf->resp.resp_iu.data[2] = %x\n"
			"tmf->resp.resp_iu.data[3] = %x\n",
			__func__,
			tmf->status,
			tmf->resp.resp_iu.datapres,
			tmf->resp.resp_iu.status,
			be32_to_cpu(tmf->resp.resp_iu.response_data_len),
			tmf->resp.resp_iu.resp_data[0],
			tmf->resp.resp_iu.resp_data[1],
			tmf->resp.resp_iu.resp_data[2],
			tmf->resp.resp_iu.resp_data[3]);
}


int isci_task_execute_task(
	struct sas_task *task,
	int num,
	gfp_t gfp_flags);

int isci_task_abort_task(
	struct sas_task *task);

int isci_task_abort_task_set(
	struct domain_device *d_device,
	u8 *lun);

int isci_task_clear_aca(
	struct domain_device *d_device,
	u8 *lun);

int isci_task_clear_task_set(
	struct domain_device *d_device,
	u8 *lun);

int isci_task_query_task(
	struct sas_task *task);

int isci_task_lu_reset(
	struct domain_device *d_device,
	u8 *lun);

int isci_task_clear_nexus_port(
	struct asd_sas_port *port);

int isci_task_clear_nexus_ha(
	struct sas_ha_struct *ha);

int isci_task_I_T_nexus_reset(
	struct domain_device *d_device);

void isci_task_request_complete(
	struct isci_host *isci_host,
	struct isci_request *request,
	enum sci_task_status completion_status);

u16 isci_task_ssp_request_get_io_tag_to_manage(
	struct isci_request *request);

u8 isci_task_ssp_request_get_function(
	struct isci_request *request);


void *isci_task_ssp_request_get_response_data_address(
	struct isci_request *request);

u32 isci_task_ssp_request_get_response_data_length(
	struct isci_request *request);

int isci_queuecommand(
	struct scsi_cmnd *scsi_cmd,
	void (*donefunc)(struct scsi_cmnd *));

int isci_bus_reset_handler(struct scsi_cmnd *cmd);

/**
 * enum isci_completion_selection - This enum defines the possible actions to
 *    take with respect to a given request's notification back to libsas.
 *
 *
 */
enum isci_completion_selection {

	isci_perform_normal_io_completion,      /* Normal notify (task_done) */
	isci_perform_aborted_io_completion,     /* No notification.   */
	isci_perform_error_io_completion        /* Use sas_task_abort */
};

static inline void isci_set_task_doneflags(
	struct sas_task *task)
{
	/* Since no futher action will be taken on this task,
	 * make sure to mark it complete from the lldd perspective.
	 */
	task->task_state_flags |= SAS_TASK_STATE_DONE;
	task->task_state_flags &= ~SAS_TASK_AT_INITIATOR;
	task->task_state_flags &= ~SAS_TASK_STATE_PENDING;
}
/**
 * isci_task_all_done() - This function clears the task bits to indicate the
 *    LLDD is done with the task.
 *
 *
 */
static inline void isci_task_all_done(
	struct sas_task *task)
{
	unsigned long flags;

	/* Since no futher action will be taken on this task,
	 * make sure to mark it complete from the lldd perspective.
	 */
	spin_lock_irqsave(&task->task_state_lock, flags);
	isci_set_task_doneflags(task);
	spin_unlock_irqrestore(&task->task_state_lock, flags);
}

/**
 * isci_task_set_completion_status() - This function sets the completion status
 *    for the request.
 * @task: This parameter is the completed request.
 * @response: This parameter is the response code for the completed task.
 * @status: This parameter is the status code for the completed task.
 *
* @return The new notification mode for the request.
*/
static inline enum isci_completion_selection
isci_task_set_completion_status(
	struct sas_task *task,
	enum service_response response,
	enum exec_status status,
	enum isci_completion_selection task_notification_selection)
{
	unsigned long flags;

	spin_lock_irqsave(&task->task_state_lock, flags);

	/* If a device reset is being indicated, make sure the I/O
	* is in the error path.
	*/
	if (task->task_state_flags & SAS_TASK_NEED_DEV_RESET) {
		/* Fail the I/O to make sure it goes into the error path. */
		response = SAS_TASK_UNDELIVERED;
		status = SAM_STAT_TASK_ABORTED;

		task_notification_selection = isci_perform_error_io_completion;
	}
	task->task_status.resp = response;
	task->task_status.stat = status;

	switch (task->task_proto) {

	case SAS_PROTOCOL_SATA:
	case SAS_PROTOCOL_STP:
	case SAS_PROTOCOL_SATA | SAS_PROTOCOL_STP:

		if (task_notification_selection
		    == isci_perform_error_io_completion) {
			/* SATA/STP I/O has it's own means of scheduling device
			* error handling on the normal path.
			*/
			task_notification_selection
				= isci_perform_normal_io_completion;
		}
		break;
	default:
		break;
	}

	switch (task_notification_selection) {

	case isci_perform_error_io_completion:

		if (task->task_proto == SAS_PROTOCOL_SMP) {
			/* There is no error escalation in the SMP case.
			 * Convert to a normal completion to avoid the
			 * timeout in the discovery path and to let the
			 * next action take place quickly.
			 */
			task_notification_selection
				= isci_perform_normal_io_completion;

			/* Fall through to the normal case... */
		} else {
			/* Use sas_task_abort */
			/* Leave SAS_TASK_STATE_DONE clear
			 * Leave SAS_TASK_AT_INITIATOR set.
			 */
			break;
		}

	case isci_perform_aborted_io_completion:
		/* This path can occur with task-managed requests as well as
		 * requests terminated because of LUN or device resets.
		 */
		/* Fall through to the normal case... */
	case isci_perform_normal_io_completion:
		/* Normal notification (task_done) */
		isci_set_task_doneflags(task);
		break;
	default:
		WARN_ONCE(1, "unknown task_notification_selection: %d\n",
			 task_notification_selection);
		break;
	}

	spin_unlock_irqrestore(&task->task_state_lock, flags);

	return task_notification_selection;

}
/**
* isci_execpath_callback() - This function is called from the task
* execute path when the task needs to callback libsas about the submit-time
* task failure.  The callback occurs either through the task's done function
* or through sas_task_abort.  In the case of regular non-discovery SATA/STP I/O
* requests, libsas takes the host lock before calling execute task.  Therefore
* in this situation the host lock must be managed before calling the func.
*
* @ihost: This parameter is the controller to which the I/O request was sent.
* @task: This parameter is the I/O request.
* @func: This parameter is the function to call in the correct context.
* @status: This parameter is the status code for the completed task.
*
*/
static inline void isci_execpath_callback(struct isci_host *ihost,
					  struct sas_task  *task,
					  void (*func)(struct sas_task *))
{
	struct domain_device *dev = task->dev;

	if (dev_is_sata(dev) && task->uldd_task) {
		unsigned long flags;

		/* Since we are still in the submit path, and since
		 * libsas takes the host lock on behalf of SATA
		 * devices before I/O starts (in the non-discovery case),
		 * we need to unlock before we can call the callback function.
		 */
		raw_local_irq_save(flags);
		spin_unlock(dev->sata_dev.ap->lock);
		func(task);
		spin_lock(dev->sata_dev.ap->lock);
		raw_local_irq_restore(flags);
	} else
		func(task);
}
#endif /* !defined(_SCI_TASK_H_) */