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Diffstat (limited to 'drivers/scsi/isci/task.c')
-rw-r--r--drivers/scsi/isci/task.c781
1 files changed, 781 insertions, 0 deletions
diff --git a/drivers/scsi/isci/task.c b/drivers/scsi/isci/task.c
new file mode 100644
index 0000000000..c514b20293
--- /dev/null
+++ b/drivers/scsi/isci/task.c
@@ -0,0 +1,781 @@
+/*
+ * 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 <linux/completion.h>
+#include <linux/irqflags.h>
+#include "sas.h"
+#include <scsi/libsas.h>
+#include "remote_device.h"
+#include "remote_node_context.h"
+#include "isci.h"
+#include "request.h"
+#include "task.h"
+#include "host.h"
+
+/**
+* isci_task_refuse() - complete the request to the upper layer driver in
+* the case where an I/O needs to be completed back in the submit path.
+* @ihost: host on which the the request was queued
+* @task: request to complete
+* @response: response code for the completed task.
+* @status: status code for the completed task.
+*
+*/
+static void isci_task_refuse(struct isci_host *ihost, struct sas_task *task,
+ enum service_response response,
+ enum exec_status status)
+
+{
+ unsigned long flags;
+
+ /* Normal notification (task_done) */
+ dev_dbg(&ihost->pdev->dev, "%s: task = %p, response=%d, status=%d\n",
+ __func__, task, response, status);
+
+ spin_lock_irqsave(&task->task_state_lock, flags);
+
+ task->task_status.resp = response;
+ task->task_status.stat = status;
+
+ /* Normal notification (task_done) */
+ task->task_state_flags |= SAS_TASK_STATE_DONE;
+ task->task_state_flags &= ~SAS_TASK_STATE_PENDING;
+ task->lldd_task = NULL;
+ spin_unlock_irqrestore(&task->task_state_lock, flags);
+
+ task->task_done(task);
+}
+
+#define for_each_sas_task(num, task) \
+ for (; num > 0; num--,\
+ task = list_entry(task->list.next, struct sas_task, list))
+
+
+static inline int isci_device_io_ready(struct isci_remote_device *idev,
+ struct sas_task *task)
+{
+ return idev ? test_bit(IDEV_IO_READY, &idev->flags) ||
+ (test_bit(IDEV_IO_NCQERROR, &idev->flags) &&
+ isci_task_is_ncq_recovery(task))
+ : 0;
+}
+/**
+ * isci_task_execute_task() - This function is one of the SAS Domain Template
+ * functions. This function is called by libsas to send a task down to
+ * hardware.
+ * @task: This parameter specifies the SAS task to send.
+ * @gfp_flags: This parameter specifies the context of this call.
+ *
+ * status, zero indicates success.
+ */
+int isci_task_execute_task(struct sas_task *task, gfp_t gfp_flags)
+{
+ struct isci_host *ihost = dev_to_ihost(task->dev);
+ struct isci_remote_device *idev;
+ unsigned long flags;
+ enum sci_status status = SCI_FAILURE;
+ bool io_ready;
+ u16 tag;
+
+ spin_lock_irqsave(&ihost->scic_lock, flags);
+ idev = isci_lookup_device(task->dev);
+ io_ready = isci_device_io_ready(idev, task);
+ tag = isci_alloc_tag(ihost);
+ spin_unlock_irqrestore(&ihost->scic_lock, flags);
+
+ dev_dbg(&ihost->pdev->dev,
+ "task: %p, dev: %p idev: %p:%#lx cmd = %p\n",
+ task, task->dev, idev, idev ? idev->flags : 0,
+ task->uldd_task);
+
+ if (!idev) {
+ isci_task_refuse(ihost, task, SAS_TASK_UNDELIVERED,
+ SAS_DEVICE_UNKNOWN);
+ } else if (!io_ready || tag == SCI_CONTROLLER_INVALID_IO_TAG) {
+ /* Indicate QUEUE_FULL so that the scsi midlayer
+ * retries.
+ */
+ isci_task_refuse(ihost, task, SAS_TASK_COMPLETE,
+ SAS_QUEUE_FULL);
+ } else {
+ /* There is a device and it's ready for I/O. */
+ spin_lock_irqsave(&task->task_state_lock, flags);
+
+ if (task->task_state_flags & SAS_TASK_STATE_ABORTED) {
+ /* The I/O was aborted. */
+ spin_unlock_irqrestore(&task->task_state_lock, flags);
+
+ isci_task_refuse(ihost, task,
+ SAS_TASK_UNDELIVERED,
+ SAS_SAM_STAT_TASK_ABORTED);
+ } else {
+ struct isci_request *ireq;
+
+ /* do common allocation and init of request object. */
+ ireq = isci_io_request_from_tag(ihost, task, tag);
+ spin_unlock_irqrestore(&task->task_state_lock, flags);
+
+ /* build and send the request. */
+ /* do common allocation and init of request object. */
+ status = isci_request_execute(ihost, idev, task, ireq);
+
+ if (status != SCI_SUCCESS) {
+ if (test_bit(IDEV_GONE, &idev->flags)) {
+ /* Indicate that the device
+ * is gone.
+ */
+ isci_task_refuse(ihost, task,
+ SAS_TASK_UNDELIVERED,
+ SAS_DEVICE_UNKNOWN);
+ } else {
+ /* Indicate QUEUE_FULL so that
+ * the scsi midlayer retries.
+ * If the request failed for
+ * remote device reasons, it
+ * gets returned as
+ * SAS_TASK_UNDELIVERED next
+ * time through.
+ */
+ isci_task_refuse(ihost, task,
+ SAS_TASK_COMPLETE,
+ SAS_QUEUE_FULL);
+ }
+ }
+ }
+ }
+
+ if (status != SCI_SUCCESS && tag != SCI_CONTROLLER_INVALID_IO_TAG) {
+ spin_lock_irqsave(&ihost->scic_lock, flags);
+ /* command never hit the device, so just free
+ * the tci and skip the sequence increment
+ */
+ isci_tci_free(ihost, ISCI_TAG_TCI(tag));
+ spin_unlock_irqrestore(&ihost->scic_lock, flags);
+ }
+
+ isci_put_device(idev);
+ return 0;
+}
+
+static struct isci_request *isci_task_request_build(struct isci_host *ihost,
+ struct isci_remote_device *idev,
+ u16 tag, struct isci_tmf *isci_tmf)
+{
+ enum sci_status status = SCI_FAILURE;
+ struct isci_request *ireq = NULL;
+ struct domain_device *dev;
+
+ dev_dbg(&ihost->pdev->dev,
+ "%s: isci_tmf = %p\n", __func__, isci_tmf);
+
+ dev = idev->domain_dev;
+
+ /* do common allocation and init of request object. */
+ ireq = isci_tmf_request_from_tag(ihost, isci_tmf, tag);
+ if (!ireq)
+ return NULL;
+
+ /* let the core do it's construct. */
+ status = sci_task_request_construct(ihost, idev, tag,
+ ireq);
+
+ if (status != SCI_SUCCESS) {
+ dev_warn(&ihost->pdev->dev,
+ "%s: sci_task_request_construct failed - "
+ "status = 0x%x\n",
+ __func__,
+ status);
+ return NULL;
+ }
+
+ /* XXX convert to get this from task->tproto like other drivers */
+ if (dev->dev_type == SAS_END_DEVICE) {
+ isci_tmf->proto = SAS_PROTOCOL_SSP;
+ status = sci_task_request_construct_ssp(ireq);
+ if (status != SCI_SUCCESS)
+ return NULL;
+ }
+
+ return ireq;
+}
+
+static int isci_task_execute_tmf(struct isci_host *ihost,
+ struct isci_remote_device *idev,
+ struct isci_tmf *tmf, unsigned long timeout_ms)
+{
+ DECLARE_COMPLETION_ONSTACK(completion);
+ enum sci_status status = SCI_FAILURE;
+ struct isci_request *ireq;
+ int ret = TMF_RESP_FUNC_FAILED;
+ unsigned long flags;
+ unsigned long timeleft;
+ u16 tag;
+
+ spin_lock_irqsave(&ihost->scic_lock, flags);
+ tag = isci_alloc_tag(ihost);
+ spin_unlock_irqrestore(&ihost->scic_lock, flags);
+
+ if (tag == SCI_CONTROLLER_INVALID_IO_TAG)
+ return ret;
+
+ /* sanity check, return TMF_RESP_FUNC_FAILED
+ * if the device is not there and ready.
+ */
+ if (!idev ||
+ (!test_bit(IDEV_IO_READY, &idev->flags) &&
+ !test_bit(IDEV_IO_NCQERROR, &idev->flags))) {
+ dev_dbg(&ihost->pdev->dev,
+ "%s: idev = %p not ready (%#lx)\n",
+ __func__,
+ idev, idev ? idev->flags : 0);
+ goto err_tci;
+ } else
+ dev_dbg(&ihost->pdev->dev,
+ "%s: idev = %p\n",
+ __func__, idev);
+
+ /* Assign the pointer to the TMF's completion kernel wait structure. */
+ tmf->complete = &completion;
+ tmf->status = SCI_FAILURE_TIMEOUT;
+
+ ireq = isci_task_request_build(ihost, idev, tag, tmf);
+ if (!ireq)
+ goto err_tci;
+
+ spin_lock_irqsave(&ihost->scic_lock, flags);
+
+ /* start the TMF io. */
+ status = sci_controller_start_task(ihost, idev, ireq);
+
+ if (status != SCI_SUCCESS) {
+ dev_dbg(&ihost->pdev->dev,
+ "%s: start_io failed - status = 0x%x, request = %p\n",
+ __func__,
+ status,
+ ireq);
+ spin_unlock_irqrestore(&ihost->scic_lock, flags);
+ goto err_tci;
+ }
+ spin_unlock_irqrestore(&ihost->scic_lock, flags);
+
+ /* The RNC must be unsuspended before the TMF can get a response. */
+ isci_remote_device_resume_from_abort(ihost, idev);
+
+ /* Wait for the TMF to complete, or a timeout. */
+ timeleft = wait_for_completion_timeout(&completion,
+ msecs_to_jiffies(timeout_ms));
+
+ if (timeleft == 0) {
+ /* The TMF did not complete - this could be because
+ * of an unplug. Terminate the TMF request now.
+ */
+ isci_remote_device_suspend_terminate(ihost, idev, ireq);
+ }
+
+ isci_print_tmf(ihost, tmf);
+
+ if (tmf->status == SCI_SUCCESS)
+ ret = TMF_RESP_FUNC_COMPLETE;
+ else if (tmf->status == SCI_FAILURE_IO_RESPONSE_VALID) {
+ dev_dbg(&ihost->pdev->dev,
+ "%s: tmf.status == "
+ "SCI_FAILURE_IO_RESPONSE_VALID\n",
+ __func__);
+ ret = TMF_RESP_FUNC_COMPLETE;
+ }
+ /* Else - leave the default "failed" status alone. */
+
+ dev_dbg(&ihost->pdev->dev,
+ "%s: completed request = %p\n",
+ __func__,
+ ireq);
+
+ return ret;
+
+ err_tci:
+ spin_lock_irqsave(&ihost->scic_lock, flags);
+ isci_tci_free(ihost, ISCI_TAG_TCI(tag));
+ spin_unlock_irqrestore(&ihost->scic_lock, flags);
+
+ return ret;
+}
+
+static void isci_task_build_tmf(struct isci_tmf *tmf,
+ enum isci_tmf_function_codes code)
+{
+ memset(tmf, 0, sizeof(*tmf));
+ tmf->tmf_code = code;
+}
+
+static void isci_task_build_abort_task_tmf(struct isci_tmf *tmf,
+ enum isci_tmf_function_codes code,
+ struct isci_request *old_request)
+{
+ isci_task_build_tmf(tmf, code);
+ tmf->io_tag = old_request->io_tag;
+}
+
+/*
+ * isci_task_send_lu_reset_sas() - This function is called by of the SAS Domain
+ * Template functions.
+ * @lun: This parameter specifies the lun to be reset.
+ *
+ * status, zero indicates success.
+ */
+static int isci_task_send_lu_reset_sas(
+ struct isci_host *isci_host,
+ struct isci_remote_device *isci_device,
+ u8 *lun)
+{
+ struct isci_tmf tmf;
+ int ret = TMF_RESP_FUNC_FAILED;
+
+ dev_dbg(&isci_host->pdev->dev,
+ "%s: isci_host = %p, isci_device = %p\n",
+ __func__, isci_host, isci_device);
+ /* Send the LUN reset to the target. By the time the call returns,
+ * the TMF has fully exected in the target (in which case the return
+ * value is "TMF_RESP_FUNC_COMPLETE", or the request timed-out (or
+ * was otherwise unable to be executed ("TMF_RESP_FUNC_FAILED").
+ */
+ isci_task_build_tmf(&tmf, isci_tmf_ssp_lun_reset);
+
+ #define ISCI_LU_RESET_TIMEOUT_MS 2000 /* 2 second timeout. */
+ ret = isci_task_execute_tmf(isci_host, isci_device, &tmf, ISCI_LU_RESET_TIMEOUT_MS);
+
+ if (ret == TMF_RESP_FUNC_COMPLETE)
+ dev_dbg(&isci_host->pdev->dev,
+ "%s: %p: TMF_LU_RESET passed\n",
+ __func__, isci_device);
+ else
+ dev_dbg(&isci_host->pdev->dev,
+ "%s: %p: TMF_LU_RESET failed (%x)\n",
+ __func__, isci_device, ret);
+
+ return ret;
+}
+
+int isci_task_lu_reset(struct domain_device *dev, u8 *lun)
+{
+ struct isci_host *ihost = dev_to_ihost(dev);
+ struct isci_remote_device *idev;
+ unsigned long flags;
+ int ret = TMF_RESP_FUNC_COMPLETE;
+
+ spin_lock_irqsave(&ihost->scic_lock, flags);
+ idev = isci_get_device(dev->lldd_dev);
+ spin_unlock_irqrestore(&ihost->scic_lock, flags);
+
+ dev_dbg(&ihost->pdev->dev,
+ "%s: domain_device=%p, isci_host=%p; isci_device=%p\n",
+ __func__, dev, ihost, idev);
+
+ if (!idev) {
+ /* If the device is gone, escalate to I_T_Nexus_Reset. */
+ dev_dbg(&ihost->pdev->dev, "%s: No dev\n", __func__);
+
+ ret = TMF_RESP_FUNC_FAILED;
+ goto out;
+ }
+
+ /* Suspend the RNC, kill all TCs */
+ if (isci_remote_device_suspend_terminate(ihost, idev, NULL)
+ != SCI_SUCCESS) {
+ /* The suspend/terminate only fails if isci_get_device fails */
+ ret = TMF_RESP_FUNC_FAILED;
+ goto out;
+ }
+ /* All pending I/Os have been terminated and cleaned up. */
+ if (!test_bit(IDEV_GONE, &idev->flags)) {
+ if (dev_is_sata(dev))
+ sas_ata_schedule_reset(dev);
+ else
+ /* Send the task management part of the reset. */
+ ret = isci_task_send_lu_reset_sas(ihost, idev, lun);
+ }
+ out:
+ isci_put_device(idev);
+ return ret;
+}
+
+
+/* int (*lldd_clear_nexus_port)(struct asd_sas_port *); */
+int isci_task_clear_nexus_port(struct asd_sas_port *port)
+{
+ return TMF_RESP_FUNC_FAILED;
+}
+
+
+
+int isci_task_clear_nexus_ha(struct sas_ha_struct *ha)
+{
+ return TMF_RESP_FUNC_FAILED;
+}
+
+/* Task Management Functions. Must be called from process context. */
+
+/**
+ * isci_task_abort_task() - This function is one of the SAS Domain Template
+ * functions. This function is called by libsas to abort a specified task.
+ * @task: This parameter specifies the SAS task to abort.
+ *
+ * status, zero indicates success.
+ */
+int isci_task_abort_task(struct sas_task *task)
+{
+ struct isci_host *ihost = dev_to_ihost(task->dev);
+ DECLARE_COMPLETION_ONSTACK(aborted_io_completion);
+ struct isci_request *old_request = NULL;
+ struct isci_remote_device *idev = NULL;
+ struct isci_tmf tmf;
+ int ret = TMF_RESP_FUNC_FAILED;
+ unsigned long flags;
+ int target_done_already = 0;
+
+ /* Get the isci_request reference from the task. Note that
+ * this check does not depend on the pending request list
+ * in the device, because tasks driving resets may land here
+ * after completion in the core.
+ */
+ spin_lock_irqsave(&ihost->scic_lock, flags);
+ spin_lock(&task->task_state_lock);
+
+ old_request = task->lldd_task;
+
+ /* If task is already done, the request isn't valid */
+ if (!(task->task_state_flags & SAS_TASK_STATE_DONE) &&
+ old_request) {
+ idev = isci_get_device(task->dev->lldd_dev);
+ target_done_already = test_bit(IREQ_COMPLETE_IN_TARGET,
+ &old_request->flags);
+ }
+ spin_unlock(&task->task_state_lock);
+ spin_unlock_irqrestore(&ihost->scic_lock, flags);
+
+ dev_warn(&ihost->pdev->dev,
+ "%s: dev = %p (%s%s), task = %p, old_request == %p\n",
+ __func__, idev,
+ (dev_is_sata(task->dev) ? "STP/SATA"
+ : ((dev_is_expander(task->dev->dev_type))
+ ? "SMP"
+ : "SSP")),
+ ((idev) ? ((test_bit(IDEV_GONE, &idev->flags))
+ ? " IDEV_GONE"
+ : "")
+ : " <NULL>"),
+ task, old_request);
+
+ /* Device reset conditions signalled in task_state_flags are the
+ * responsbility of libsas to observe at the start of the error
+ * handler thread.
+ */
+ if (!idev || !old_request) {
+ /* The request has already completed and there
+ * is nothing to do here other than to set the task
+ * done bit, and indicate that the task abort function
+ * was successful.
+ */
+ spin_lock_irqsave(&task->task_state_lock, flags);
+ task->task_state_flags |= SAS_TASK_STATE_DONE;
+ task->task_state_flags &= ~SAS_TASK_STATE_PENDING;
+ spin_unlock_irqrestore(&task->task_state_lock, flags);
+
+ ret = TMF_RESP_FUNC_COMPLETE;
+
+ dev_warn(&ihost->pdev->dev,
+ "%s: abort task not needed for %p\n",
+ __func__, task);
+ goto out;
+ }
+ /* Suspend the RNC, kill the TC */
+ if (isci_remote_device_suspend_terminate(ihost, idev, old_request)
+ != SCI_SUCCESS) {
+ dev_warn(&ihost->pdev->dev,
+ "%s: isci_remote_device_reset_terminate(dev=%p, "
+ "req=%p, task=%p) failed\n",
+ __func__, idev, old_request, task);
+ ret = TMF_RESP_FUNC_FAILED;
+ goto out;
+ }
+ spin_lock_irqsave(&ihost->scic_lock, flags);
+
+ if (task->task_proto == SAS_PROTOCOL_SMP ||
+ sas_protocol_ata(task->task_proto) ||
+ target_done_already ||
+ test_bit(IDEV_GONE, &idev->flags)) {
+
+ spin_unlock_irqrestore(&ihost->scic_lock, flags);
+
+ /* No task to send, so explicitly resume the device here */
+ isci_remote_device_resume_from_abort(ihost, idev);
+
+ dev_warn(&ihost->pdev->dev,
+ "%s: %s request"
+ " or complete_in_target (%d), "
+ "or IDEV_GONE (%d), thus no TMF\n",
+ __func__,
+ ((task->task_proto == SAS_PROTOCOL_SMP)
+ ? "SMP"
+ : (sas_protocol_ata(task->task_proto)
+ ? "SATA/STP"
+ : "<other>")
+ ),
+ test_bit(IREQ_COMPLETE_IN_TARGET,
+ &old_request->flags),
+ test_bit(IDEV_GONE, &idev->flags));
+
+ spin_lock_irqsave(&task->task_state_lock, flags);
+ task->task_state_flags &= ~SAS_TASK_STATE_PENDING;
+ task->task_state_flags |= SAS_TASK_STATE_DONE;
+ spin_unlock_irqrestore(&task->task_state_lock, flags);
+
+ ret = TMF_RESP_FUNC_COMPLETE;
+ } else {
+ /* Fill in the tmf structure */
+ isci_task_build_abort_task_tmf(&tmf, isci_tmf_ssp_task_abort,
+ old_request);
+
+ spin_unlock_irqrestore(&ihost->scic_lock, flags);
+
+ /* Send the task management request. */
+ #define ISCI_ABORT_TASK_TIMEOUT_MS 500 /* 1/2 second timeout */
+ ret = isci_task_execute_tmf(ihost, idev, &tmf,
+ ISCI_ABORT_TASK_TIMEOUT_MS);
+ }
+out:
+ dev_warn(&ihost->pdev->dev,
+ "%s: Done; dev = %p, task = %p , old_request == %p\n",
+ __func__, idev, task, old_request);
+ isci_put_device(idev);
+ return ret;
+}
+
+/**
+ * isci_task_abort_task_set() - This function is one of the SAS Domain Template
+ * functions. This is one of the Task Management functoins called by libsas,
+ * to abort all task for the given lun.
+ * @d_device: This parameter specifies the domain device associated with this
+ * request.
+ * @lun: This parameter specifies the lun associated with this request.
+ *
+ * status, zero indicates success.
+ */
+int isci_task_abort_task_set(
+ struct domain_device *d_device,
+ u8 *lun)
+{
+ return TMF_RESP_FUNC_FAILED;
+}
+
+
+/**
+ * isci_task_clear_task_set() - This function is one of the SAS Domain Template
+ * functions. This is one of the Task Management functoins called by libsas.
+ * @d_device: This parameter specifies the domain device associated with this
+ * request.
+ * @lun: This parameter specifies the lun associated with this request.
+ *
+ * status, zero indicates success.
+ */
+int isci_task_clear_task_set(
+ struct domain_device *d_device,
+ u8 *lun)
+{
+ return TMF_RESP_FUNC_FAILED;
+}
+
+
+/**
+ * isci_task_query_task() - This function is implemented to cause libsas to
+ * correctly escalate the failed abort to a LUN or target reset (this is
+ * because sas_scsi_find_task libsas function does not correctly interpret
+ * all return codes from the abort task call). When TMF_RESP_FUNC_SUCC is
+ * returned, libsas turns this into a LUN reset; when FUNC_FAILED is
+ * returned, libsas will turn this into a target reset
+ * @task: This parameter specifies the sas task being queried.
+ *
+ * status, zero indicates success.
+ */
+int isci_task_query_task(
+ struct sas_task *task)
+{
+ /* See if there is a pending device reset for this device. */
+ if (task->task_state_flags & SAS_TASK_NEED_DEV_RESET)
+ return TMF_RESP_FUNC_FAILED;
+ else
+ return TMF_RESP_FUNC_SUCC;
+}
+
+/*
+ * isci_task_request_complete() - This function is called by the sci core when
+ * an task request completes.
+ * @ihost: This parameter specifies the ISCI host object
+ * @ireq: This parameter is the completed isci_request object.
+ * @completion_status: This parameter specifies the completion status from the
+ * sci core.
+ *
+ * none.
+ */
+void
+isci_task_request_complete(struct isci_host *ihost,
+ struct isci_request *ireq,
+ enum sci_task_status completion_status)
+{
+ struct isci_tmf *tmf = isci_request_access_tmf(ireq);
+ struct completion *tmf_complete = NULL;
+
+ dev_dbg(&ihost->pdev->dev,
+ "%s: request = %p, status=%d\n",
+ __func__, ireq, completion_status);
+
+ set_bit(IREQ_COMPLETE_IN_TARGET, &ireq->flags);
+
+ if (tmf) {
+ tmf->status = completion_status;
+
+ if (tmf->proto == SAS_PROTOCOL_SSP) {
+ memcpy(tmf->resp.rsp_buf,
+ ireq->ssp.rsp_buf,
+ SSP_RESP_IU_MAX_SIZE);
+ } else if (tmf->proto == SAS_PROTOCOL_SATA) {
+ memcpy(&tmf->resp.d2h_fis,
+ &ireq->stp.rsp,
+ sizeof(struct dev_to_host_fis));
+ }
+ /* PRINT_TMF( ((struct isci_tmf *)request->task)); */
+ tmf_complete = tmf->complete;
+ }
+ sci_controller_complete_io(ihost, ireq->target_device, ireq);
+ /* set the 'terminated' flag handle to make sure it cannot be terminated
+ * or completed again.
+ */
+ set_bit(IREQ_TERMINATED, &ireq->flags);
+
+ if (test_and_clear_bit(IREQ_ABORT_PATH_ACTIVE, &ireq->flags))
+ wake_up_all(&ihost->eventq);
+
+ if (!test_bit(IREQ_NO_AUTO_FREE_TAG, &ireq->flags))
+ isci_free_tag(ihost, ireq->io_tag);
+
+ /* The task management part completes last. */
+ if (tmf_complete)
+ complete(tmf_complete);
+}
+
+static int isci_reset_device(struct isci_host *ihost,
+ struct domain_device *dev,
+ struct isci_remote_device *idev)
+{
+ int rc = TMF_RESP_FUNC_COMPLETE, reset_stat = -1;
+ struct sas_phy *phy = sas_get_local_phy(dev);
+ struct isci_port *iport = dev->port->lldd_port;
+
+ dev_dbg(&ihost->pdev->dev, "%s: idev %p\n", __func__, idev);
+
+ /* Suspend the RNC, terminate all outstanding TCs. */
+ if (isci_remote_device_suspend_terminate(ihost, idev, NULL)
+ != SCI_SUCCESS) {
+ rc = TMF_RESP_FUNC_FAILED;
+ goto out;
+ }
+ /* Note that since the termination for outstanding requests succeeded,
+ * this function will return success. This is because the resets will
+ * only fail if the device has been removed (ie. hotplug), and the
+ * primary duty of this function is to cleanup tasks, so that is the
+ * relevant status.
+ */
+ if (!test_bit(IDEV_GONE, &idev->flags)) {
+ if (scsi_is_sas_phy_local(phy)) {
+ struct isci_phy *iphy = &ihost->phys[phy->number];
+
+ reset_stat = isci_port_perform_hard_reset(ihost, iport,
+ iphy);
+ } else
+ reset_stat = sas_phy_reset(phy, !dev_is_sata(dev));
+ }
+ /* Explicitly resume the RNC here, since there was no task sent. */
+ isci_remote_device_resume_from_abort(ihost, idev);
+
+ dev_dbg(&ihost->pdev->dev, "%s: idev %p complete, reset_stat=%d.\n",
+ __func__, idev, reset_stat);
+ out:
+ sas_put_local_phy(phy);
+ return rc;
+}
+
+int isci_task_I_T_nexus_reset(struct domain_device *dev)
+{
+ struct isci_host *ihost = dev_to_ihost(dev);
+ struct isci_remote_device *idev;
+ unsigned long flags;
+ int ret;
+
+ spin_lock_irqsave(&ihost->scic_lock, flags);
+ idev = isci_get_device(dev->lldd_dev);
+ spin_unlock_irqrestore(&ihost->scic_lock, flags);
+
+ if (!idev) {
+ /* XXX: need to cleanup any ireqs targeting this
+ * domain_device
+ */
+ ret = -ENODEV;
+ goto out;
+ }
+
+ ret = isci_reset_device(ihost, dev, idev);
+ out:
+ isci_put_device(idev);
+ return ret;
+}