isci: Removed sci_base_object from scic_sds_request.

[linux-2.6/linux-acpi-2.6/ibm-acpi-2.6.git] / drivers / scsi / isci / request.c

/*
 * 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.
 */

#include "isci.h"
#include "scic_io_request.h"
#include "scic_task_request.h"
#include "scic_port.h"
#include "task.h"
#include "request.h"
#include "sata.h"
#include "scu_completion_codes.h"
#include "core/scic_sds_request.h"

static enum sci_status isci_request_ssp_request_construct(
        struct isci_request *request)
{
        enum sci_status status;

        dev_dbg(&request->isci_host->pdev->dev,
                "%s: request = %p\n",
                __func__,
                request);
        status = scic_io_request_construct_basic_ssp(
                request->sci_request_handle
                );
        return status;
}

static enum sci_status isci_request_stp_request_construct(
        struct isci_request *request)
{
        struct sas_task *task = isci_request_access_task(request);
        enum sci_status status;
        struct host_to_dev_fis *register_fis;

        dev_dbg(&request->isci_host->pdev->dev,
                "%s: request = %p\n",
                __func__,
                request);

        /* Get the host_to_dev_fis from the core and copy
         * the fis from the task into it.
         */
        register_fis = isci_sata_task_to_fis_copy(task);

        status = scic_io_request_construct_basic_sata(
                request->sci_request_handle
                );

        /* Set the ncq tag in the fis, from the queue
         * command in the task.
         */
        if (isci_sata_is_task_ncq(task)) {

                isci_sata_set_ncq_tag(
                        register_fis,
                        task
                        );
        }

        return status;
}

/**
 * isci_smp_request_build() - This function builds the smp request object.
 * @isci_host: This parameter specifies the ISCI host object
 * @request: This parameter points to the isci_request object allocated in the
 *    request construct function.
 * @sci_device: This parameter is the handle for the sci core's remote device
 *    object that is the destination for this request.
 *
 * SCI_SUCCESS on successfull completion, or specific failure code.
 */
static enum sci_status isci_smp_request_build(
        struct isci_request *request)
{
        enum sci_status status = SCI_FAILURE;
        struct sas_task *task = isci_request_access_task(request);

        void *command_iu_address =
                scic_io_request_get_command_iu_address(
                        request->sci_request_handle
                        );

        dev_dbg(&request->isci_host->pdev->dev,
                "%s: request = %p\n",
                __func__,
                request);
        dev_dbg(&request->isci_host->pdev->dev,
                "%s: smp_req len = %d\n",
                __func__,
                task->smp_task.smp_req.length);

        /* copy the smp_command to the address; */
        sg_copy_to_buffer(&task->smp_task.smp_req, 1,
                          (char *)command_iu_address,
                          sizeof(struct smp_request)
                          );

        status = scic_io_request_construct_smp(request->sci_request_handle);
        if (status != SCI_SUCCESS)
                dev_warn(&request->isci_host->pdev->dev,
                         "%s: scic_io_request_construct_smp failed with "
                         "status = %d\n",
                         __func__,
                         status);

        return status;
}

/**
 * isci_io_request_build() - This function builds the io request object.
 * @isci_host: This parameter specifies the ISCI host object
 * @request: This parameter points to the isci_request object allocated in the
 *    request construct function.
 * @sci_device: This parameter is the handle for the sci core's remote device
 *    object that is the destination for this request.
 *
 * SCI_SUCCESS on successfull completion, or specific failure code.
 */
static enum sci_status isci_io_request_build(
        struct isci_host *isci_host,
        struct isci_request *request,
        struct isci_remote_device *isci_device)
{
        enum sci_status status = SCI_SUCCESS;
        struct sas_task *task = isci_request_access_task(request);
        struct scic_sds_remote_device *sci_device = &isci_device->sci;

        dev_dbg(&isci_host->pdev->dev,
                "%s: isci_device = 0x%p; request = %p, "
                "num_scatter = %d\n",
                __func__,
                isci_device,
                request,
                task->num_scatter);

        /* map the sgl addresses, if present.
         * libata does the mapping for sata devices
         * before we get the request.
         */
        if (task->num_scatter &&
            !sas_protocol_ata(task->task_proto) &&
            !(SAS_PROTOCOL_SMP & task->task_proto)) {

                request->num_sg_entries = dma_map_sg(
                        &isci_host->pdev->dev,
                        task->scatter,
                        task->num_scatter,
                        task->data_dir
                        );

                if (request->num_sg_entries == 0)
                        return SCI_FAILURE_INSUFFICIENT_RESOURCES;
        }

        /* build the common request object. For now,
         * we will let the core allocate the IO tag.
         */
        status = scic_io_request_construct(
                isci_host->core_controller,
                sci_device,
                SCI_CONTROLLER_INVALID_IO_TAG,
                request,
                request->sci_request_mem_ptr,
                (struct scic_sds_request **)&request->sci_request_handle
                );

        if (status != SCI_SUCCESS) {
                dev_warn(&isci_host->pdev->dev,
                         "%s: failed request construct\n",
                         __func__);
                return SCI_FAILURE;
        }

        request->sci_request_handle->ireq = request;

        switch (task->task_proto) {
        case SAS_PROTOCOL_SMP:
                status = isci_smp_request_build(request);
                break;
        case SAS_PROTOCOL_SSP:
                status = isci_request_ssp_request_construct(request);
                break;
        case SAS_PROTOCOL_SATA:
        case SAS_PROTOCOL_STP:
        case SAS_PROTOCOL_SATA | SAS_PROTOCOL_STP:
                status = isci_request_stp_request_construct(request);
                break;
        default:
                dev_warn(&isci_host->pdev->dev,
                         "%s: unknown protocol\n", __func__);
                return SCI_FAILURE;
        }

        return SCI_SUCCESS;
}


/**
 * isci_request_alloc_core() - This function gets the request object from the
 *    isci_host dma cache.
 * @isci_host: This parameter specifies the ISCI host object
 * @isci_request: This parameter will contain the pointer to the new
 *    isci_request object.
 * @isci_device: This parameter is the pointer to the isci remote device object
 *    that is the destination for this request.
 * @gfp_flags: This parameter specifies the os allocation flags.
 *
 * SCI_SUCCESS on successfull completion, or specific failure code.
 */
static int isci_request_alloc_core(
        struct isci_host *isci_host,
        struct isci_request **isci_request,
        struct isci_remote_device *isci_device,
        gfp_t gfp_flags)
{
        int ret = 0;
        dma_addr_t handle;
        struct isci_request *request;


        /* get pointer to dma memory. This actually points
         * to both the isci_remote_device object and the
         * sci object. The isci object is at the beginning
         * of the memory allocated here.
         */
        request = dma_pool_alloc(isci_host->dma_pool, gfp_flags, &handle);
        if (!request) {
                dev_warn(&isci_host->pdev->dev,
                         "%s: dma_pool_alloc returned NULL\n", __func__);
                return -ENOMEM;
        }

        /* initialize the request object.       */
        spin_lock_init(&request->state_lock);
        request->sci_request_mem_ptr = ((u8 *)request) +
                                       sizeof(struct isci_request);
        request->request_daddr = handle;
        request->isci_host = isci_host;
        request->isci_device = isci_device;
        request->io_request_completion = NULL;

        request->request_alloc_size = isci_host->dma_pool_alloc_size;
        request->num_sg_entries = 0;

        request->complete_in_target = false;

        INIT_LIST_HEAD(&request->completed_node);
        INIT_LIST_HEAD(&request->dev_node);

        *isci_request = request;
        isci_request_change_state(request, allocated);

        return ret;
}

static int isci_request_alloc_io(
        struct isci_host *isci_host,
        struct sas_task *task,
        struct isci_request **isci_request,
        struct isci_remote_device *isci_device,
        gfp_t gfp_flags)
{
        int retval = isci_request_alloc_core(isci_host, isci_request,
                                             isci_device, gfp_flags);

        if (!retval) {
                (*isci_request)->ttype_ptr.io_task_ptr = task;
                (*isci_request)->ttype                 = io_task;

                task->lldd_task = *isci_request;
        }
        return retval;
}

/**
 * isci_request_alloc_tmf() - This function gets the request object from the
 *    isci_host dma cache and initializes the relevant fields as a sas_task.
 * @isci_host: This parameter specifies the ISCI host object
 * @sas_task: This parameter is the task struct from the upper layer driver.
 * @isci_request: This parameter will contain the pointer to the new
 *    isci_request object.
 * @isci_device: This parameter is the pointer to the isci remote device object
 *    that is the destination for this request.
 * @gfp_flags: This parameter specifies the os allocation flags.
 *
 * SCI_SUCCESS on successfull completion, or specific failure code.
 */
int isci_request_alloc_tmf(
        struct isci_host *isci_host,
        struct isci_tmf *isci_tmf,
        struct isci_request **isci_request,
        struct isci_remote_device *isci_device,
        gfp_t gfp_flags)
{
        int retval = isci_request_alloc_core(isci_host, isci_request,
                                             isci_device, gfp_flags);

        if (!retval) {

                (*isci_request)->ttype_ptr.tmf_task_ptr = isci_tmf;
                (*isci_request)->ttype = tmf_task;
        }
        return retval;
}

/**
 * isci_request_execute() - This function allocates the isci_request object,
 *    all fills in some common fields.
 * @isci_host: This parameter specifies the ISCI host object
 * @sas_task: This parameter is the task struct from the upper layer driver.
 * @isci_request: This parameter will contain the pointer to the new
 *    isci_request object.
 * @gfp_flags: This parameter specifies the os allocation flags.
 *
 * SCI_SUCCESS on successfull completion, or specific failure code.
 */
int isci_request_execute(
        struct isci_host *isci_host,
        struct sas_task *task,
        struct isci_request **isci_request,
        gfp_t gfp_flags)
{
        int ret = 0;
        struct scic_sds_remote_device *sci_device;
        enum sci_status status = SCI_FAILURE_UNSUPPORTED_PROTOCOL;
        struct isci_remote_device *isci_device;
        struct isci_request *request;
        unsigned long flags;

        isci_device = task->dev->lldd_dev;
        sci_device = &isci_device->sci;

        /* do common allocation and init of request object. */
        ret = isci_request_alloc_io(
                isci_host,
                task,
                &request,
                isci_device,
                gfp_flags
                );

        if (ret)
                goto out;

        status = isci_io_request_build(isci_host, request, isci_device);
        if (status == SCI_SUCCESS) {

                spin_lock_irqsave(&isci_host->scic_lock, flags);

                /* send the request, let the core assign the IO TAG.    */
                status = scic_controller_start_io(
                        isci_host->core_controller,
                        sci_device,
                        request->sci_request_handle,
                        SCI_CONTROLLER_INVALID_IO_TAG
                        );

                if (status == SCI_SUCCESS ||
                    status == SCI_FAILURE_REMOTE_DEVICE_RESET_REQUIRED) {

                        /* Either I/O started OK, or the core has signaled that
                         * the device needs a target reset.
                         *
                         * In either case, hold onto the I/O for later.
                         *
                         * Update it's status and add it to the list in the
                         * remote device object.
                         */
                        isci_request_change_state(request, started);
                        list_add(&request->dev_node,
                                 &isci_device->reqs_in_process);

                        if (status == SCI_SUCCESS) {
                                /* Save the tag for possible task mgmt later. */
                                request->io_tag = scic_io_request_get_io_tag(
                                                     request->sci_request_handle);
                        } else {
                                /* The request did not really start in the
                                 * hardware, so clear the request handle
                                 * here so no terminations will be done.
                                 */
                                request->sci_request_handle = NULL;
                        }

                } else
                        dev_warn(&isci_host->pdev->dev,
                                 "%s: failed request start (0x%x)\n",
                                 __func__, status);

                spin_unlock_irqrestore(&isci_host->scic_lock, flags);

                if (status ==
                    SCI_FAILURE_REMOTE_DEVICE_RESET_REQUIRED) {
                        /* Signal libsas that we need the SCSI error
                        * handler thread to work on this I/O and that
                        * we want a device reset.
                        */
                        spin_lock_irqsave(&task->task_state_lock, flags);
                        task->task_state_flags |= SAS_TASK_NEED_DEV_RESET;
                        spin_unlock_irqrestore(&task->task_state_lock, flags);

                        /* Cause this task to be scheduled in the SCSI error
                        * handler thread.
                        */
                        isci_execpath_callback(isci_host, task,
                                               sas_task_abort);

                        /* Change the status, since we are holding
                        * the I/O until it is managed by the SCSI
                        * error handler.
                        */
                        status = SCI_SUCCESS;
                }

        } else
                dev_warn(&isci_host->pdev->dev,
                         "%s: request_construct failed - status = 0x%x\n",
                         __func__,
                         status);

 out:
        if (status != SCI_SUCCESS) {
                /* release dma memory on failure. */
                isci_request_free(isci_host, request);
                request = NULL;
                ret = SCI_FAILURE;
        }

        *isci_request = request;
        return ret;
}


/**
 * isci_request_process_response_iu() - This function sets the status and
 *    response iu, in the task struct, from the request object for the upper
 *    layer driver.
 * @sas_task: This parameter is the task struct from the upper layer driver.
 * @resp_iu: This parameter points to the response iu of the completed request.
 * @dev: This parameter specifies the linux device struct.
 *
 * none.
 */
static void isci_request_process_response_iu(
        struct sas_task *task,
        struct ssp_response_iu *resp_iu,
        struct device *dev)
{
        dev_dbg(dev,
                "%s: resp_iu = %p "
                "resp_iu->status = 0x%x,\nresp_iu->datapres = %d "
                "resp_iu->response_data_len = %x, "
                "resp_iu->sense_data_len = %x\nrepsonse data: ",
                __func__,
                resp_iu,
                resp_iu->status,
                resp_iu->datapres,
                resp_iu->response_data_len,
                resp_iu->sense_data_len);

        task->task_status.stat = resp_iu->status;

        /* libsas updates the task status fields based on the response iu. */
        sas_ssp_task_response(dev, task, resp_iu);
}

/**
 * isci_request_set_open_reject_status() - This function prepares the I/O
 *    completion for OPEN_REJECT conditions.
 * @request: This parameter is the completed isci_request object.
 * @response_ptr: This parameter specifies the service response for the I/O.
 * @status_ptr: This parameter specifies the exec status for the I/O.
 * @complete_to_host_ptr: This parameter specifies the action to be taken by
 *    the LLDD with respect to completing this request or forcing an abort
 *    condition on the I/O.
 * @open_rej_reason: This parameter specifies the encoded reason for the
 *    abandon-class reject.
 *
 * none.
 */
static void isci_request_set_open_reject_status(
        struct isci_request *request,
        struct sas_task *task,
        enum service_response *response_ptr,
        enum exec_status *status_ptr,
        enum isci_completion_selection *complete_to_host_ptr,
        enum sas_open_rej_reason open_rej_reason)
{
        /* Task in the target is done. */
        request->complete_in_target       = true;
        *response_ptr                     = SAS_TASK_UNDELIVERED;
        *status_ptr                       = SAS_OPEN_REJECT;
        *complete_to_host_ptr             = isci_perform_normal_io_completion;
        task->task_status.open_rej_reason = open_rej_reason;
}

/**
 * isci_request_handle_controller_specific_errors() - This function decodes
 *    controller-specific I/O completion error conditions.
 * @request: This parameter is the completed isci_request object.
 * @response_ptr: This parameter specifies the service response for the I/O.
 * @status_ptr: This parameter specifies the exec status for the I/O.
 * @complete_to_host_ptr: This parameter specifies the action to be taken by
 *    the LLDD with respect to completing this request or forcing an abort
 *    condition on the I/O.
 *
 * none.
 */
static void isci_request_handle_controller_specific_errors(
        struct isci_remote_device *isci_device,
        struct isci_request *request,
        struct sas_task *task,
        enum service_response *response_ptr,
        enum exec_status *status_ptr,
        enum isci_completion_selection *complete_to_host_ptr)
{
        unsigned int cstatus;

        cstatus = scic_request_get_controller_status(
                request->sci_request_handle
                );

        dev_dbg(&request->isci_host->pdev->dev,
                "%s: %p SCI_FAILURE_CONTROLLER_SPECIFIC_IO_ERR "
                "- controller status = 0x%x\n",
                __func__, request, cstatus);

        /* Decode the controller-specific errors; most
         * important is to recognize those conditions in which
         * the target may still have a task outstanding that
         * must be aborted.
         *
         * Note that there are SCU completion codes being
         * named in the decode below for which SCIC has already
         * done work to handle them in a way other than as
         * a controller-specific completion code; these are left
         * in the decode below for completeness sake.
         */
        switch (cstatus) {
        case SCU_TASK_DONE_DMASETUP_DIRERR:
        /* Also SCU_TASK_DONE_SMP_FRM_TYPE_ERR: */
        case SCU_TASK_DONE_XFERCNT_ERR:
                /* Also SCU_TASK_DONE_SMP_UFI_ERR: */
                if (task->task_proto == SAS_PROTOCOL_SMP) {
                        /* SCU_TASK_DONE_SMP_UFI_ERR == Task Done. */
                        *response_ptr = SAS_TASK_COMPLETE;

                        /* See if the device has been/is being stopped. Note
                         * that we ignore the quiesce state, since we are
                         * concerned about the actual device state.
                         */
                        if ((isci_device->status == isci_stopping) ||
                            (isci_device->status == isci_stopped))
                                *status_ptr = SAS_DEVICE_UNKNOWN;
                        else
                                *status_ptr = SAS_ABORTED_TASK;

                        request->complete_in_target = true;

                        *complete_to_host_ptr =
                                isci_perform_normal_io_completion;
                } else {
                        /* Task in the target is not done. */
                        *response_ptr = SAS_TASK_UNDELIVERED;

                        if ((isci_device->status == isci_stopping) ||
                            (isci_device->status == isci_stopped))
                                *status_ptr = SAS_DEVICE_UNKNOWN;
                        else
                                *status_ptr = SAM_STAT_TASK_ABORTED;

                        request->complete_in_target = false;

                        *complete_to_host_ptr =
                                isci_perform_error_io_completion;
                }

                break;

        case SCU_TASK_DONE_CRC_ERR:
        case SCU_TASK_DONE_NAK_CMD_ERR:
        case SCU_TASK_DONE_EXCESS_DATA:
        case SCU_TASK_DONE_UNEXP_FIS:
        /* Also SCU_TASK_DONE_UNEXP_RESP: */
        case SCU_TASK_DONE_VIIT_ENTRY_NV:       /* TODO - conditions? */
        case SCU_TASK_DONE_IIT_ENTRY_NV:        /* TODO - conditions? */
        case SCU_TASK_DONE_RNCNV_OUTBOUND:      /* TODO - conditions? */
                /* These are conditions in which the target
                 * has completed the task, so that no cleanup
                 * is necessary.
                 */
                *response_ptr = SAS_TASK_COMPLETE;

                /* See if the device has been/is being stopped. Note
                 * that we ignore the quiesce state, since we are
                 * concerned about the actual device state.
                 */
                if ((isci_device->status == isci_stopping) ||
                    (isci_device->status == isci_stopped))
                        *status_ptr = SAS_DEVICE_UNKNOWN;
                else
                        *status_ptr = SAS_ABORTED_TASK;

                request->complete_in_target = true;

                *complete_to_host_ptr = isci_perform_normal_io_completion;
                break;


        /* Note that the only open reject completion codes seen here will be
         * abandon-class codes; all others are automatically retried in the SCU.
         */
        case SCU_TASK_OPEN_REJECT_WRONG_DESTINATION:

                isci_request_set_open_reject_status(
                        request, task, response_ptr, status_ptr,
                        complete_to_host_ptr, SAS_OREJ_WRONG_DEST);
                break;

        case SCU_TASK_OPEN_REJECT_ZONE_VIOLATION:

                /* Note - the return of AB0 will change when
                 * libsas implements detection of zone violations.
                 */
                isci_request_set_open_reject_status(
                        request, task, response_ptr, status_ptr,
                        complete_to_host_ptr, SAS_OREJ_RESV_AB0);
                break;

        case SCU_TASK_OPEN_REJECT_RESERVED_ABANDON_1:

                isci_request_set_open_reject_status(
                        request, task, response_ptr, status_ptr,
                        complete_to_host_ptr, SAS_OREJ_RESV_AB1);
                break;

        case SCU_TASK_OPEN_REJECT_RESERVED_ABANDON_2:

                isci_request_set_open_reject_status(
                        request, task, response_ptr, status_ptr,
                        complete_to_host_ptr, SAS_OREJ_RESV_AB2);
                break;

        case SCU_TASK_OPEN_REJECT_RESERVED_ABANDON_3:

                isci_request_set_open_reject_status(
                        request, task, response_ptr, status_ptr,
                        complete_to_host_ptr, SAS_OREJ_RESV_AB3);
                break;

        case SCU_TASK_OPEN_REJECT_BAD_DESTINATION:

                isci_request_set_open_reject_status(
                        request, task, response_ptr, status_ptr,
                        complete_to_host_ptr, SAS_OREJ_BAD_DEST);
                break;

        case SCU_TASK_OPEN_REJECT_STP_RESOURCES_BUSY:

                isci_request_set_open_reject_status(
                        request, task, response_ptr, status_ptr,
                        complete_to_host_ptr, SAS_OREJ_STP_NORES);
                break;

        case SCU_TASK_OPEN_REJECT_PROTOCOL_NOT_SUPPORTED:

                isci_request_set_open_reject_status(
                        request, task, response_ptr, status_ptr,
                        complete_to_host_ptr, SAS_OREJ_EPROTO);
                break;

        case SCU_TASK_OPEN_REJECT_CONNECTION_RATE_NOT_SUPPORTED:

                isci_request_set_open_reject_status(
                        request, task, response_ptr, status_ptr,
                        complete_to_host_ptr, SAS_OREJ_CONN_RATE);
                break;

        case SCU_TASK_DONE_LL_R_ERR:
        /* Also SCU_TASK_DONE_ACK_NAK_TO: */
        case SCU_TASK_DONE_LL_PERR:
        case SCU_TASK_DONE_LL_SY_TERM:
        /* Also SCU_TASK_DONE_NAK_ERR:*/
        case SCU_TASK_DONE_LL_LF_TERM:
        /* Also SCU_TASK_DONE_DATA_LEN_ERR: */
        case SCU_TASK_DONE_LL_ABORT_ERR:
        case SCU_TASK_DONE_SEQ_INV_TYPE:
        /* Also SCU_TASK_DONE_UNEXP_XR: */
        case SCU_TASK_DONE_XR_IU_LEN_ERR:
        case SCU_TASK_DONE_INV_FIS_LEN:
        /* Also SCU_TASK_DONE_XR_WD_LEN: */
        case SCU_TASK_DONE_SDMA_ERR:
        case SCU_TASK_DONE_OFFSET_ERR:
        case SCU_TASK_DONE_MAX_PLD_ERR:
        case SCU_TASK_DONE_LF_ERR:
        case SCU_TASK_DONE_SMP_RESP_TO_ERR:  /* Escalate to dev reset? */
        case SCU_TASK_DONE_SMP_LL_RX_ERR:
        case SCU_TASK_DONE_UNEXP_DATA:
        case SCU_TASK_DONE_UNEXP_SDBFIS:
        case SCU_TASK_DONE_REG_ERR:
        case SCU_TASK_DONE_SDB_ERR:
        case SCU_TASK_DONE_TASK_ABORT:
        default:
                /* Task in the target is not done. */
                *response_ptr = SAS_TASK_UNDELIVERED;
                *status_ptr = SAM_STAT_TASK_ABORTED;
                request->complete_in_target = false;

                *complete_to_host_ptr = isci_perform_error_io_completion;
                break;
        }
}

/**
 * isci_task_save_for_upper_layer_completion() - This function saves the
 *    request for later completion to the upper layer driver.
 * @host: This parameter is a pointer to the host on which the the request
 *    should be queued (either as an error or success).
 * @request: 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.
 *
 * none.
 */
static void isci_task_save_for_upper_layer_completion(
        struct isci_host *host,
        struct isci_request *request,
        enum service_response response,
        enum exec_status status,
        enum isci_completion_selection task_notification_selection)
{
        struct sas_task *task = isci_request_access_task(request);

        task_notification_selection
                = isci_task_set_completion_status(task, response, status,
                                                  task_notification_selection);

        /* Tasks aborted specifically by a call to the lldd_abort_task
         * function should not be completed to the host in the regular path.
         */
        switch (task_notification_selection) {

        case isci_perform_normal_io_completion:

                /* Normal notification (task_done) */
                dev_dbg(&host->pdev->dev,
                        "%s: Normal - task = %p, response=%d (%d), status=%d (%d)\n",
                        __func__,
                        task,
                        task->task_status.resp, response,
                        task->task_status.stat, status);
                /* Add to the completed list. */
                list_add(&request->completed_node,
                         &host->requests_to_complete);

                /* Take the request off the device's pending request list. */
                list_del_init(&request->dev_node);
                break;

        case isci_perform_aborted_io_completion:
                /* No notification to libsas because this request is
                 * already in the abort path.
                 */
                dev_warn(&host->pdev->dev,
                         "%s: Aborted - task = %p, response=%d (%d), status=%d (%d)\n",
                         __func__,
                         task,
                         task->task_status.resp, response,
                         task->task_status.stat, status);

                /* Wake up whatever process was waiting for this
                 * request to complete.
                 */
                WARN_ON(request->io_request_completion == NULL);

                if (request->io_request_completion != NULL) {

                        /* Signal whoever is waiting that this
                        * request is complete.
                        */
                        complete(request->io_request_completion);
                }
                break;

        case isci_perform_error_io_completion:
                /* Use sas_task_abort */
                dev_warn(&host->pdev->dev,
                         "%s: Error - task = %p, response=%d (%d), status=%d (%d)\n",
                         __func__,
                         task,
                         task->task_status.resp, response,
                         task->task_status.stat, status);
                /* Add to the aborted list. */
                list_add(&request->completed_node,
                         &host->requests_to_errorback);
                break;

        default:
                dev_warn(&host->pdev->dev,
                         "%s: Unknown - task = %p, response=%d (%d), status=%d (%d)\n",
                         __func__,
                         task,
                         task->task_status.resp, response,
                         task->task_status.stat, status);

                /* Add to the error to libsas list. */
                list_add(&request->completed_node,
                         &host->requests_to_errorback);
                break;
        }
}

/**
 * isci_request_io_request_complete() - This function is called by the sci core
 *    when an io request completes.
 * @isci_host: This parameter specifies the ISCI host object
 * @request: This parameter is the completed isci_request object.
 * @completion_status: This parameter specifies the completion status from the
 *    sci core.
 *
 * none.
 */
void isci_request_io_request_complete(
        struct        isci_host *isci_host,
        struct        isci_request *request,
        enum sci_io_status completion_status)
{
        struct sas_task *task = isci_request_access_task(request);
        struct ssp_response_iu *resp_iu;
        void *resp_buf;
        unsigned long task_flags;
        struct isci_remote_device *isci_device   = request->isci_device;
        enum service_response response       = SAS_TASK_UNDELIVERED;
        enum exec_status status         = SAS_ABORTED_TASK;
        enum isci_request_status request_status;
        enum isci_completion_selection complete_to_host
                = isci_perform_normal_io_completion;

        dev_dbg(&isci_host->pdev->dev,
                "%s: request = %p, task = %p,\n"
                "task->data_dir = %d completion_status = 0x%x\n",
                __func__,
                request,
                task,
                task->data_dir,
                completion_status);

        spin_lock(&request->state_lock);
        request_status = isci_request_get_state(request);

        /* Decode the request status.  Note that if the request has been
         * aborted by a task management function, we don't care
         * what the status is.
         */
        switch (request_status) {

        case aborted:
                /* "aborted" indicates that the request was aborted by a task
                 * management function, since once a task management request is
                 * perfomed by the device, the request only completes because
                 * of the subsequent driver terminate.
                 *
                 * Aborted also means an external thread is explicitly managing
                 * this request, so that we do not complete it up the stack.
                 *
                 * The target is still there (since the TMF was successful).
                 */
                request->complete_in_target = true;
                response = SAS_TASK_COMPLETE;

                /* See if the device has been/is being stopped. Note
                 * that we ignore the quiesce state, since we are
                 * concerned about the actual device state.
                 */
                if ((isci_device->status == isci_stopping)
                    || (isci_device->status == isci_stopped)
                    )
                        status = SAS_DEVICE_UNKNOWN;
                else
                        status = SAS_ABORTED_TASK;

                complete_to_host = isci_perform_aborted_io_completion;
                /* This was an aborted request. */

                spin_unlock(&request->state_lock);
                break;

        case aborting:
                /* aborting means that the task management function tried and
                 * failed to abort the request. We need to note the request
                 * as SAS_TASK_UNDELIVERED, so that the scsi mid layer marks the
                 * target as down.
                 *
                 * Aborting also means an external thread is explicitly managing
                 * this request, so that we do not complete it up the stack.
                 */
                request->complete_in_target = true;
                response = SAS_TASK_UNDELIVERED;

                if ((isci_device->status == isci_stopping) ||
                    (isci_device->status == isci_stopped))
                        /* The device has been /is being stopped. Note that
                         * we ignore the quiesce state, since we are
                         * concerned about the actual device state.
                         */
                        status = SAS_DEVICE_UNKNOWN;
                else
                        status = SAS_PHY_DOWN;

                complete_to_host = isci_perform_aborted_io_completion;

                /* This was an aborted request. */

                spin_unlock(&request->state_lock);
                break;

        case terminating:

                /* This was an terminated request.  This happens when
                 * the I/O is being terminated because of an action on
                 * the device (reset, tear down, etc.), and the I/O needs
                 * to be completed up the stack.
                 */
                request->complete_in_target = true;
                response = SAS_TASK_UNDELIVERED;

                /* See if the device has been/is being stopped. Note
                 * that we ignore the quiesce state, since we are
                 * concerned about the actual device state.
                 */
                if ((isci_device->status == isci_stopping) ||
                    (isci_device->status == isci_stopped))
                        status = SAS_DEVICE_UNKNOWN;
                else
                        status = SAS_ABORTED_TASK;

                complete_to_host = isci_perform_aborted_io_completion;

                /* This was a terminated request. */

                spin_unlock(&request->state_lock);
                break;

        default:

                /* The request is done from an SCU HW perspective. */
                request->status = completed;

                spin_unlock(&request->state_lock);

                /* This is an active request being completed from the core. */
                switch (completion_status) {

                case SCI_IO_FAILURE_RESPONSE_VALID:
                        dev_dbg(&isci_host->pdev->dev,
                                "%s: SCI_IO_FAILURE_RESPONSE_VALID (%p/%p)\n",
                                __func__,
                                request,
                                task);

                        if (sas_protocol_ata(task->task_proto)) {
                                resp_buf
                                        = scic_stp_io_request_get_d2h_reg_address(
                                        request->sci_request_handle
                                        );
                                isci_request_process_stp_response(task,
                                                                  resp_buf
                                                                  );

                        } else if (SAS_PROTOCOL_SSP == task->task_proto) {

                                /* crack the iu response buffer. */
                                resp_iu
                                        = scic_io_request_get_response_iu_address(
                                        request->sci_request_handle
                                        );

                                isci_request_process_response_iu(task, resp_iu,
                                                                 &isci_host->pdev->dev
                                                                 );

                        } else if (SAS_PROTOCOL_SMP == task->task_proto) {

                                dev_err(&isci_host->pdev->dev,
                                        "%s: SCI_IO_FAILURE_RESPONSE_VALID: "
                                        "SAS_PROTOCOL_SMP protocol\n",
                                        __func__);

                        } else
                                dev_err(&isci_host->pdev->dev,
                                        "%s: unknown protocol\n", __func__);

                        /* use the task status set in the task struct by the
                         * isci_request_process_response_iu call.
                         */
                        request->complete_in_target = true;
                        response = task->task_status.resp;
                        status = task->task_status.stat;
                        break;

                case SCI_IO_SUCCESS:
                case SCI_IO_SUCCESS_IO_DONE_EARLY:

                        response = SAS_TASK_COMPLETE;
                        status   = SAM_STAT_GOOD;
                        request->complete_in_target = true;

                        if (task->task_proto == SAS_PROTOCOL_SMP) {

                                u8 *command_iu_address
                                        = scic_io_request_get_command_iu_address(
                                        request->sci_request_handle
                                        );

                                dev_dbg(&isci_host->pdev->dev,
                                        "%s: SMP protocol completion\n",
                                        __func__);

                                sg_copy_from_buffer(
                                        &task->smp_task.smp_resp, 1,
                                        command_iu_address
                                        + sizeof(struct smp_request),
                                        sizeof(struct smp_resp)
                                        );
                        } else if (completion_status
                                   == SCI_IO_SUCCESS_IO_DONE_EARLY) {

                                /* This was an SSP / STP / SATA transfer.
                                 * There is a possibility that less data than
                                 * the maximum was transferred.
                                 */
                                u32 transferred_length
                                        = scic_io_request_get_number_of_bytes_transferred(
                                        request->sci_request_handle);

                                task->task_status.residual
                                        = task->total_xfer_len - transferred_length;

                                /* If there were residual bytes, call this an
                                 * underrun.
                                 */
                                if (task->task_status.residual != 0)
                                        status = SAS_DATA_UNDERRUN;

                                dev_dbg(&isci_host->pdev->dev,
                                        "%s: SCI_IO_SUCCESS_IO_DONE_EARLY %d\n",
                                        __func__,
                                        status);

                        } else
                                dev_dbg(&isci_host->pdev->dev,
                                        "%s: SCI_IO_SUCCESS\n",
                                        __func__);

                        break;

                case SCI_IO_FAILURE_TERMINATED:
                        dev_dbg(&isci_host->pdev->dev,
                                "%s: SCI_IO_FAILURE_TERMINATED (%p/%p)\n",
                                __func__,
                                request,
                                task);

                        /* The request was terminated explicitly.  No handling
                         * is needed in the SCSI error handler path.
                         */
                        request->complete_in_target = true;
                        response = SAS_TASK_UNDELIVERED;

                        /* See if the device has been/is being stopped. Note
                         * that we ignore the quiesce state, since we are
                         * concerned about the actual device state.
                         */
                        if ((isci_device->status == isci_stopping) ||
                            (isci_device->status == isci_stopped))
                                status = SAS_DEVICE_UNKNOWN;
                        else
                                status = SAS_ABORTED_TASK;

                        complete_to_host = isci_perform_normal_io_completion;
                        break;

                case SCI_FAILURE_CONTROLLER_SPECIFIC_IO_ERR:

                        isci_request_handle_controller_specific_errors(
                                isci_device, request, task, &response, &status,
                                &complete_to_host);

                        break;

                case SCI_IO_FAILURE_REMOTE_DEVICE_RESET_REQUIRED:
                        /* This is a special case, in that the I/O completion
                         * is telling us that the device needs a reset.
                         * In order for the device reset condition to be
                         * noticed, the I/O has to be handled in the error
                         * handler.  Set the reset flag and cause the
                         * SCSI error thread to be scheduled.
                         */
                        spin_lock_irqsave(&task->task_state_lock, task_flags);
                        task->task_state_flags |= SAS_TASK_NEED_DEV_RESET;
                        spin_unlock_irqrestore(&task->task_state_lock, task_flags);

                        /* Fail the I/O. */
                        response = SAS_TASK_UNDELIVERED;
                        status = SAM_STAT_TASK_ABORTED;

                        complete_to_host = isci_perform_error_io_completion;
                        request->complete_in_target = false;
                        break;

                default:
                        /* Catch any otherwise unhandled error codes here. */
                        dev_warn(&isci_host->pdev->dev,
                                 "%s: invalid completion code: 0x%x - "
                                 "isci_request = %p\n",
                                 __func__, completion_status, request);

                        response = SAS_TASK_UNDELIVERED;

                        /* See if the device has been/is being stopped. Note
                         * that we ignore the quiesce state, since we are
                         * concerned about the actual device state.
                         */
                        if ((isci_device->status == isci_stopping) ||
                            (isci_device->status == isci_stopped))
                                status = SAS_DEVICE_UNKNOWN;
                        else
                                status = SAS_ABORTED_TASK;

                        complete_to_host = isci_perform_error_io_completion;
                        request->complete_in_target = false;
                        break;
                }
                break;
        }

        isci_request_unmap_sgl(request, isci_host->pdev);

        /* Put the completed request on the correct list */
        isci_task_save_for_upper_layer_completion(isci_host, request, response,
                                                  status, complete_to_host
                                                  );

        /* complete the io request to the core. */
        scic_controller_complete_io(isci_host->core_controller,
                                    &isci_device->sci,
                                    request->sci_request_handle);
        /* NULL the request handle so it cannot be completed or
         * terminated again, and to cause any calls into abort
         * task to recognize the already completed case.
         */
        request->sci_request_handle = NULL;

        isci_host_can_dequeue(isci_host, 1);
}

/**
 * isci_request_io_request_get_transfer_length() - This function is called by
 *    the sci core to retrieve the transfer length for a given request.
 * @request: This parameter is the isci_request object.
 *
 * length of transfer for specified request.
 */
u32 isci_request_io_request_get_transfer_length(struct isci_request *request)
{
        struct sas_task *task = isci_request_access_task(request);

        dev_dbg(&request->isci_host->pdev->dev,
                "%s: total_xfer_len: %d\n",
                __func__,
                task->total_xfer_len);
        return task->total_xfer_len;
}


/**
 * isci_request_io_request_get_data_direction() - This function is called by
 *    the sci core to retrieve the data direction for a given request.
 * @request: This parameter is the isci_request object.
 *
 * data direction for specified request.
 */
enum dma_data_direction isci_request_io_request_get_data_direction(
        struct isci_request *request)
{
        struct sas_task *task = isci_request_access_task(request);

        return task->data_dir;
}

/**
 * isci_request_sge_get_address_field() - This function is called by the sci
 *    core to retrieve the address field contents for a given sge.
 * @request: This parameter is the isci_request object.
 * @sge_address: This parameter is the sge.
 *
 * physical address in the specified sge.
 */


/**
 * isci_request_sge_get_length_field() - This function is called by the sci
 *    core to retrieve the length field contents for a given sge.
 * @request: This parameter is the isci_request object.
 * @sge_address: This parameter is the sge.
 *
 * length field value in the specified sge.
 */


/**
 * isci_request_ssp_io_request_get_cdb_address() - This function is called by
 *    the sci core to retrieve the cdb address for a given request.
 * @request: This parameter is the isci_request object.
 *
 * cdb address for specified request.
 */
void *isci_request_ssp_io_request_get_cdb_address(
        struct isci_request *request)
{
        struct sas_task *task = isci_request_access_task(request);

        dev_dbg(&request->isci_host->pdev->dev,
                "%s: request->task->ssp_task.cdb = %p\n",
                __func__,
                task->ssp_task.cdb);
        return task->ssp_task.cdb;
}


/**
 * isci_request_ssp_io_request_get_cdb_length() - This function is called by
 *    the sci core to retrieve the cdb length for a given request.
 * @request: This parameter is the isci_request object.
 *
 * cdb length for specified request.
 */
u32 isci_request_ssp_io_request_get_cdb_length(
        struct isci_request *request)
{
        return 16;
}


/**
 * isci_request_ssp_io_request_get_lun() - This function is called by the sci
 *    core to retrieve the lun for a given request.
 * @request: This parameter is the isci_request object.
 *
 * lun for specified request.
 */
u32 isci_request_ssp_io_request_get_lun(
        struct isci_request *request)
{
        struct sas_task *task = isci_request_access_task(request);

#ifdef DEBUG
        int i;

        for (i = 0; i < 8; i++)
                dev_dbg(&request->isci_host->pdev->dev,
                        "%s: task->ssp_task.LUN[%d] = %x\n",
                        __func__, i, task->ssp_task.LUN[i]);

#endif

        return task->ssp_task.LUN[0];
}


/**
 * isci_request_ssp_io_request_get_task_attribute() - This function is called
 *    by the sci core to retrieve the task attribute for a given request.
 * @request: This parameter is the isci_request object.
 *
 * task attribute for specified request.
 */
u32 isci_request_ssp_io_request_get_task_attribute(
        struct isci_request *request)
{
        struct sas_task *task = isci_request_access_task(request);

        dev_dbg(&request->isci_host->pdev->dev,
                "%s: request->task->ssp_task.task_attr = %x\n",
                __func__,
                task->ssp_task.task_attr);

        return task->ssp_task.task_attr;
}


/**
 * isci_request_ssp_io_request_get_command_priority() - This function is called
 *    by the sci core to retrieve the command priority for a given request.
 * @request: This parameter is the isci_request object.
 *
 * command priority for specified request.
 */
u32 isci_request_ssp_io_request_get_command_priority(
        struct isci_request *request)
{
        struct sas_task *task = isci_request_access_task(request);

        dev_dbg(&request->isci_host->pdev->dev,
                "%s: request->task->ssp_task.task_prio = %x\n",
                __func__,
                task->ssp_task.task_prio);

        return task->ssp_task.task_prio;
}