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path: root/drivers/scsi/aic94xx/aic94xx_tmf.c
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/*
 * Aic94xx Task Management Functions
 *
 * Copyright (C) 2005 Adaptec, Inc.  All rights reserved.
 * Copyright (C) 2005 Luben Tuikov <luben_tuikov@adaptec.com>
 *
 * This file is licensed under GPLv2.
 *
 * This file is part of the aic94xx driver.
 *
 * The aic94xx driver is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License as
 * published by the Free Software Foundation; version 2 of the
 * License.
 *
 * The aic94xx driver 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 the aic94xx driver; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
 *
 */

#include <linux/spinlock.h>
#include <linux/gfp.h>
#include "aic94xx.h"
#include "aic94xx_sas.h"
#include "aic94xx_hwi.h"

/* ---------- Internal enqueue ---------- */

static int asd_enqueue_internal(struct asd_ascb *ascb,
		void (*tasklet_complete)(struct asd_ascb *,
					 struct done_list_struct *),
				void (*timed_out)(unsigned long))
{
	int res;

	ascb->tasklet_complete = tasklet_complete;
	ascb->uldd_timer = 1;

	ascb->timer.data = (unsigned long) ascb;
	ascb->timer.function = timed_out;
	ascb->timer.expires = jiffies + AIC94XX_SCB_TIMEOUT;

	add_timer(&ascb->timer);

	res = asd_post_ascb_list(ascb->ha, ascb, 1);
	if (unlikely(res))
		del_timer(&ascb->timer);
	return res;
}

/* ---------- CLEAR NEXUS ---------- */

struct tasklet_completion_status {
	int	dl_opcode;
	int	tmf_state;
	u8	tag_valid:1;
	__be16	tag;
};

#define DECLARE_TCS(tcs) \
	struct tasklet_completion_status tcs = { \
		.dl_opcode = 0, \
		.tmf_state = 0, \
		.tag_valid = 0, \
		.tag = 0, \
	}


static void asd_clear_nexus_tasklet_complete(struct asd_ascb *ascb,
					     struct done_list_struct *dl)
{
	struct tasklet_completion_status *tcs = ascb->uldd_task;
	ASD_DPRINTK("%s: here\n", __func__);
	if (!del_timer(&ascb->timer)) {
		ASD_DPRINTK("%s: couldn't delete timer\n", __func__);
		return;
	}
	ASD_DPRINTK("%s: opcode: 0x%x\n", __func__, dl->opcode);
	tcs->dl_opcode = dl->opcode;
	complete(ascb->completion);
	asd_ascb_free(ascb);
}

static void asd_clear_nexus_timedout(unsigned long data)
{
	struct asd_ascb *ascb = (void *)data;
	struct tasklet_completion_status *tcs = ascb->uldd_task;

	ASD_DPRINTK("%s: here\n", __func__);
	tcs->dl_opcode = TMF_RESP_FUNC_FAILED;
	complete(ascb->completion);
}

#define CLEAR_NEXUS_PRE         \
	struct asd_ascb *ascb; \
	struct scb *scb; \
	int res; \
	DECLARE_COMPLETION_ONSTACK(completion); \
	DECLARE_TCS(tcs); \
		\
	ASD_DPRINTK("%s: PRE\n", __func__); \
        res = 1;                \
	ascb = asd_ascb_alloc_list(asd_ha, &res, GFP_KERNEL); \
	if (!ascb)              \
		return -ENOMEM; \
                                \
	ascb->completion = &completion; \
	ascb->uldd_task = &tcs; \
	scb = ascb->scb;        \
	scb->header.opcode = CLEAR_NEXUS

#define CLEAR_NEXUS_POST        \
	ASD_DPRINTK("%s: POST\n", __func__); \
	res = asd_enqueue_internal(ascb, asd_clear_nexus_tasklet_complete, \
				   asd_clear_nexus_timedout);              \
	if (res)                \
		goto out_err;   \
	ASD_DPRINTK("%s: clear nexus posted, waiting...\n", __func__); \
	wait_for_completion(&completion); \
	res = tcs.dl_opcode; \
	if (res == TC_NO_ERROR) \
		res = TMF_RESP_FUNC_COMPLETE;   \
	return res; \
out_err:                        \
	asd_ascb_free(ascb);    \
	return res

int asd_clear_nexus_ha(struct sas_ha_struct *sas_ha)
{
	struct asd_ha_struct *asd_ha = sas_ha->lldd_ha;

	CLEAR_NEXUS_PRE;
	scb->clear_nexus.nexus = NEXUS_ADAPTER;
	CLEAR_NEXUS_POST;
}

int asd_clear_nexus_port(struct asd_sas_port *port)
{
	struct asd_ha_struct *asd_ha = port->ha->lldd_ha;

	CLEAR_NEXUS_PRE;
	scb->clear_nexus.nexus = NEXUS_PORT;
	scb->clear_nexus.conn_mask = port->phy_mask;
	CLEAR_NEXUS_POST;
}

enum clear_nexus_phase {
	NEXUS_PHASE_PRE,
	NEXUS_PHASE_POST,
	NEXUS_PHASE_RESUME,
};

static int asd_clear_nexus_I_T(struct domain_device *dev,
			       enum clear_nexus_phase phase)
{
	struct asd_ha_struct *asd_ha = dev->port->ha->lldd_ha;

	CLEAR_NEXUS_PRE;
	scb->clear_nexus.nexus = NEXUS_I_T;
	switch (phase) {
	case NEXUS_PHASE_PRE:
		scb->clear_nexus.flags = EXEC_Q | SUSPEND_TX;
		break;
	case NEXUS_PHASE_POST:
		scb->clear_nexus.flags = SEND_Q | NOTINQ;
		break;
	case NEXUS_PHASE_RESUME:
		scb->clear_nexus.flags = RESUME_TX;
	}
	scb->clear_nexus.conn_handle = cpu_to_le16((u16)(unsigned long)
						   dev->lldd_dev);
	CLEAR_NEXUS_POST;
}

int asd_I_T_nexus_reset(struct domain_device *dev)
{
	int res, tmp_res, i;
	struct sas_phy *phy = sas_find_local_phy(dev);
	/* Standard mandates link reset for ATA  (type 0) and
	 * hard reset for SSP (type 1) */
	int reset_type = (dev->dev_type == SATA_DEV ||
			  (dev->tproto & SAS_PROTOCOL_STP)) ? 0 : 1;

	asd_clear_nexus_I_T(dev, NEXUS_PHASE_PRE);
	/* send a hard reset */
	ASD_DPRINTK("sending %s reset to %s\n",
		    reset_type ? "hard" : "soft", dev_name(&phy->dev));
	res = sas_phy_reset(phy, reset_type);
	if (res == TMF_RESP_FUNC_COMPLETE) {
		/* wait for the maximum settle time */
		msleep(500);
		/* clear all outstanding commands (keep nexus suspended) */
		asd_clear_nexus_I_T(dev, NEXUS_PHASE_POST);
	}
	for (i = 0 ; i < 3; i++) {
		tmp_res = asd_clear_nexus_I_T(dev, NEXUS_PHASE_RESUME);
		if (tmp_res == TC_RESUME)
			return res;
		msleep(500);
	}

	/* This is a bit of a problem:  the sequencer is still suspended
	 * and is refusing to resume.  Hope it will resume on a bigger hammer
	 * or the disk is lost */
	dev_printk(KERN_ERR, &phy->dev,
		   "Failed to resume nexus after reset 0x%x\n", tmp_res);

	return TMF_RESP_FUNC_FAILED;
}

static int asd_clear_nexus_I_T_L(struct domain_device *dev, u8 *lun)
{
	struct asd_ha_struct *asd_ha = dev->port->ha->lldd_ha;

	CLEAR_NEXUS_PRE;
	scb->clear_nexus.nexus = NEXUS_I_T_L;
	scb->clear_nexus.flags = SEND_Q | EXEC_Q | NOTINQ;
	memcpy(scb->clear_nexus.ssp_task.lun, lun, 8);
	scb->clear_nexus.conn_handle = cpu_to_le16((u16)(unsigned long)
						   dev->lldd_dev);
	CLEAR_NEXUS_POST;
}

static int asd_clear_nexus_tag(struct sas_task *task)
{
	struct asd_ha_struct *asd_ha = task->dev->port->ha->lldd_ha;
	struct asd_ascb *tascb = task->lldd_task;

	CLEAR_NEXUS_PRE;
	scb->clear_nexus.nexus = NEXUS_TAG;
	memcpy(scb->clear_nexus.ssp_task.lun, task->ssp_task.LUN, 8);
	scb->clear_nexus.ssp_task.tag = tascb->tag;
	if (task->dev->tproto)
		scb->clear_nexus.conn_handle = cpu_to_le16((u16)(unsigned long)
							  task->dev->lldd_dev);
	CLEAR_NEXUS_POST;
}

static int asd_clear_nexus_index(struct sas_task *task)
{
	struct asd_ha_struct *asd_ha = task->dev->port->ha->lldd_ha;
	struct asd_ascb *tascb = task->lldd_task;

	CLEAR_NEXUS_PRE;
	scb->clear_nexus.nexus = NEXUS_TRANS_CX;
	if (task->dev->tproto)
		scb->clear_nexus.conn_handle = cpu_to_le16((u16)(unsigned long)
							  task->dev->lldd_dev);
	scb->clear_nexus.index = cpu_to_le16(tascb->tc_index);
	CLEAR_NEXUS_POST;
}

/* ---------- TMFs ---------- */

static void asd_tmf_timedout(unsigned long data)
{
	struct asd_ascb *ascb = (void *) data;
	struct tasklet_completion_status *tcs = ascb->uldd_task;

	ASD_DPRINTK("tmf timed out\n");
	tcs->tmf_state = TMF_RESP_FUNC_FAILED;
	complete(ascb->completion);
}

static int asd_get_tmf_resp_tasklet(struct asd_ascb *ascb,
				    struct done_list_struct *dl)
{
	struct asd_ha_struct *asd_ha = ascb->ha;
	unsigned long flags;
	struct tc_resp_sb_struct {
		__le16 index_escb;
		u8     len_lsb;
		u8     flags;
	} __attribute__ ((packed)) *resp_sb = (void *) dl->status_block;

	int  edb_id = ((resp_sb->flags & 0x70) >> 4)-1;
	struct asd_ascb *escb;
	struct asd_dma_tok *edb;
	struct ssp_frame_hdr *fh;
	struct ssp_response_iu   *ru;
	int res = TMF_RESP_FUNC_FAILED;

	ASD_DPRINTK("tmf resp tasklet\n");

	spin_lock_irqsave(&asd_ha->seq.tc_index_lock, flags);
	escb = asd_tc_index_find(&asd_ha->seq,
				 (int)le16_to_cpu(resp_sb->index_escb));
	spin_unlock_irqrestore(&asd_ha->seq.tc_index_lock, flags);

	if (!escb) {
		ASD_DPRINTK("Uh-oh! No escb for this dl?!\n");
		return res;
	}

	edb = asd_ha->seq.edb_arr[edb_id + escb->edb_index];
	ascb->tag = *(__be16 *)(edb->vaddr+4);
	fh = edb->vaddr + 16;
	ru = edb->vaddr + 16 + sizeof(*fh);
	res = ru->status;
	if (ru->datapres == 1)	  /* Response data present */
		res = ru->resp_data[3];
#if 0
	ascb->tag = fh->tag;
#endif
	ascb->tag_valid = 1;

	asd_invalidate_edb(escb, edb_id);
	return res;
}

static void asd_tmf_tasklet_complete(struct asd_ascb *ascb,
				     struct done_list_struct *dl)
{
	struct tasklet_completion_status *tcs;

	if (!del_timer(&ascb->timer))
		return;

	tcs = ascb->uldd_task;
	ASD_DPRINTK("tmf tasklet complete\n");

	tcs->dl_opcode = dl->opcode;

	if (dl->opcode == TC_SSP_RESP) {
		tcs->tmf_state = asd_get_tmf_resp_tasklet(ascb, dl);
		tcs->tag_valid = ascb->tag_valid;
		tcs->tag = ascb->tag;
	}

	complete(ascb->completion);
	asd_ascb_free(ascb);
}

static int asd_clear_nexus(struct sas_task *task)
{
	int res = TMF_RESP_FUNC_FAILED;
	int leftover;
	struct asd_ascb *tascb = task->lldd_task;
	DECLARE_COMPLETION_ONSTACK(completion);
	unsigned long flags;

	tascb->completion = &completion;

	ASD_DPRINTK("task not done, clearing nexus\n");
	if (tascb->tag_valid)
		res = asd_clear_nexus_tag(task);
	else
		res = asd_clear_nexus_index(task);
	leftover = wait_for_completion_timeout(&completion,
					       AIC94XX_SCB_TIMEOUT);
	tascb->completion = NULL;
	ASD_DPRINTK("came back from clear nexus\n");
	spin_lock_irqsave(&task->task_state_lock, flags);
	if (leftover < 1)
		res = TMF_RESP_FUNC_FAILED;
	if (task->task_state_flags & SAS_TASK_STATE_DONE)
		res = TMF_RESP_FUNC_COMPLETE;
	spin_unlock_irqrestore(&task->task_state_lock, flags);

	return res;
}

/**
 * asd_abort_task -- ABORT TASK TMF
 * @task: the task to be aborted
 *
 * Before calling ABORT TASK the task state flags should be ORed with
 * SAS_TASK_STATE_ABORTED (unless SAS_TASK_STATE_DONE is set) under
 * the task_state_lock IRQ spinlock, then ABORT TASK *must* be called.
 *
 * Implements the ABORT TASK TMF, I_T_L_Q nexus.
 * Returns: SAS TMF responses (see sas_task.h),
 *          -ENOMEM,
 *          -SAS_QUEUE_FULL.
 *
 * When ABORT TASK returns, the caller of ABORT TASK checks first the
 * task->task_state_flags, and then the return value of ABORT TASK.
 *
 * If the task has task state bit SAS_TASK_STATE_DONE set, then the
 * task was completed successfully prior to it being aborted.  The
 * caller of ABORT TASK has responsibility to call task->task_done()
 * xor free the task, depending on their framework.  The return code
 * is TMF_RESP_FUNC_FAILED in this case.
 *
 * Else the SAS_TASK_STATE_DONE bit is not set,
 * 	If the return code is TMF_RESP_FUNC_COMPLETE, then
 * 		the task was aborted successfully.  The caller of
 * 		ABORT TASK has responsibility to call task->task_done()
 *              to finish the task, xor free the task depending on their
 *		framework.
 *	else
 * 		the ABORT TASK returned some kind of error. The task
 *              was _not_ cancelled.  Nothing can be assumed.
 *		The caller of ABORT TASK may wish to retry.
 */
int asd_abort_task(struct sas_task *task)
{
	struct asd_ascb *tascb = task->lldd_task;
	struct asd_ha_struct *asd_ha = tascb->ha;
	int res = 1;
	unsigned long flags;
	struct asd_ascb *ascb = NULL;
	struct scb *scb;
	int leftover;
	DECLARE_TCS(tcs);
	DECLARE_COMPLETION_ONSTACK(completion);
	DECLARE_COMPLETION_ONSTACK(tascb_completion);

	tascb->completion = &tascb_completion;

	spin_lock_irqsave(&task->task_state_lock, flags);
	if (task->task_state_flags & SAS_TASK_STATE_DONE) {
		spin_unlock_irqrestore(&task->task_state_lock, flags);
		res = TMF_RESP_FUNC_COMPLETE;
		ASD_DPRINTK("%s: task 0x%p done\n", __func__, task);
		goto out_done;
	}
	spin_unlock_irqrestore(&task->task_state_lock, flags);

	ascb = asd_ascb_alloc_list(asd_ha, &res, GFP_KERNEL);
	if (!ascb)
		return -ENOMEM;

	ascb->uldd_task = &tcs;
	ascb->completion = &completion;
	scb = ascb->scb;
	scb->header.opcode = SCB_ABORT_TASK;

	switch (task->task_proto) {
	case SAS_PROTOCOL_SATA:
	case SAS_PROTOCOL_STP:
		scb->abort_task.proto_conn_rate = (1 << 5); /* STP */
		break;
	case SAS_PROTOCOL_SSP:
		scb->abort_task.proto_conn_rate  = (1 << 4); /* SSP */
		scb->abort_task.proto_conn_rate |= task->dev->linkrate;
		break;
	case SAS_PROTOCOL_SMP:
		break;
	default:
		break;
	}

	if (task->task_proto == SAS_PROTOCOL_SSP) {
		scb->abort_task.ssp_frame.frame_type = SSP_TASK;
		memcpy(scb->abort_task.ssp_frame.hashed_dest_addr,
		       task->dev->hashed_sas_addr, HASHED_SAS_ADDR_SIZE);
		memcpy(scb->abort_task.ssp_frame.hashed_src_addr,
		       task->dev->port->ha->hashed_sas_addr,
		       HASHED_SAS_ADDR_SIZE);
		scb->abort_task.ssp_frame.tptt = cpu_to_be16(0xFFFF);

		memcpy(scb->abort_task.ssp_task.lun, task->ssp_task.LUN, 8);
		scb->abort_task.ssp_task.tmf = TMF_ABORT_TASK;
		scb->abort_task.ssp_task.tag = cpu_to_be16(0xFFFF);
	}

	scb->abort_task.sister_scb = cpu_to_le16(0xFFFF);
	scb->abort_task.conn_handle = cpu_to_le16(
		(u16)(unsigned long)task->dev->lldd_dev);
	scb->abort_task.retry_count = 1;
	scb->abort_task.index = cpu_to_le16((u16)tascb->tc_index);
	scb->abort_task.itnl_to = cpu_to_le16(ITNL_TIMEOUT_CONST);

	res = asd_enqueue_internal(ascb, asd_tmf_tasklet_complete,
				   asd_tmf_timedout);
	if (res)
		goto out_free;
	wait_for_completion(&completion);
	ASD_DPRINTK("tmf came back\n");

	tascb->tag = tcs.tag;
	tascb->tag_valid = tcs.tag_valid;

	spin_lock_irqsave(&task->task_state_lock, flags);
	if (task->task_state_flags & SAS_TASK_STATE_DONE) {
		spin_unlock_irqrestore(&task->task_state_lock, flags);
		res = TMF_RESP_FUNC_COMPLETE;
		ASD_DPRINTK("%s: task 0x%p done\n", __func__, task);
		goto out_done;
	}
	spin_unlock_irqrestore(&task->task_state_lock, flags);

	if (tcs.dl_opcode == TC_SSP_RESP) {
		/* The task to be aborted has been sent to the device.
		 * We got a Response IU for the ABORT TASK TMF. */
		if (tcs.tmf_state == TMF_RESP_FUNC_COMPLETE)
			res = asd_clear_nexus(task);
		else
			res = tcs.tmf_state;
	} else if (tcs.dl_opcode == TC_NO_ERROR &&
		   tcs.tmf_state == TMF_RESP_FUNC_FAILED) {
		/* timeout */
		res = TMF_RESP_FUNC_FAILED;
	} else {
		/* In the following we assume that the managing layer
		 * will _never_ make a mistake, when issuing ABORT
		 * TASK.
		 */
		switch (tcs.dl_opcode) {
		default:
			res = asd_clear_nexus(task);
			/* fallthrough */
		case TC_NO_ERROR:
			break;
			/* The task hasn't been sent to the device xor
			 * we never got a (sane) Response IU for the
			 * ABORT TASK TMF.
			 */
		case TF_NAK_RECV:
			res = TMF_RESP_INVALID_FRAME;
			break;
		case TF_TMF_TASK_DONE:	/* done but not reported yet */
			res = TMF_RESP_FUNC_FAILED;
			leftover =
				wait_for_completion_timeout(&tascb_completion,
							  AIC94XX_SCB_TIMEOUT);
			spin_lock_irqsave(&task->task_state_lock, flags);
			if (leftover < 1)
				res = TMF_RESP_FUNC_FAILED;
			if (task->task_state_flags & SAS_TASK_STATE_DONE)
				res = TMF_RESP_FUNC_COMPLETE;
			spin_unlock_irqrestore(&task->task_state_lock, flags);
			break;
		case TF_TMF_NO_TAG:
		case TF_TMF_TAG_FREE: /* the tag is in the free list */
		case TF_TMF_NO_CONN_HANDLE: /* no such device */
			res = TMF_RESP_FUNC_COMPLETE;
			break;
		case TF_TMF_NO_CTX: /* not in seq, or proto != SSP */
			res = TMF_RESP_FUNC_ESUPP;
			break;
		}
	}
 out_done:
	tascb->completion = NULL;
	if (res == TMF_RESP_FUNC_COMPLETE) {
		task->lldd_task = NULL;
		mb();
		asd_ascb_free(tascb);
	}
	ASD_DPRINTK("task 0x%p aborted, res: 0x%x\n", task, res);
	return res;

 out_free:
	asd_ascb_free(ascb);
	ASD_DPRINTK("task 0x%p aborted, res: 0x%x\n", task, res);
	return res;
}

/**
 * asd_initiate_ssp_tmf -- send a TMF to an I_T_L or I_T_L_Q nexus
 * @dev: pointer to struct domain_device of interest
 * @lun: pointer to u8[8] which is the LUN
 * @tmf: the TMF to be performed (see sas_task.h or the SAS spec)
 * @index: the transaction context of the task to be queried if QT TMF
 *
 * This function is used to send ABORT TASK SET, CLEAR ACA,
 * CLEAR TASK SET, LU RESET and QUERY TASK TMFs.
 *
 * No SCBs should be queued to the I_T_L nexus when this SCB is
 * pending.
 *
 * Returns: TMF response code (see sas_task.h or the SAS spec)
 */
static int asd_initiate_ssp_tmf(struct domain_device *dev, u8 *lun,
				int tmf, int index)
{
	struct asd_ha_struct *asd_ha = dev->port->ha->lldd_ha;
	struct asd_ascb *ascb;
	int res = 1;
	struct scb *scb;
	DECLARE_COMPLETION_ONSTACK(completion);
	DECLARE_TCS(tcs);

	if (!(dev->tproto & SAS_PROTOCOL_SSP))
		return TMF_RESP_FUNC_ESUPP;

	ascb = asd_ascb_alloc_list(asd_ha, &res, GFP_KERNEL);
	if (!ascb)
		return -ENOMEM;

	ascb->completion = &completion;
	ascb->uldd_task = &tcs;
	scb = ascb->scb;

	if (tmf == TMF_QUERY_TASK)
		scb->header.opcode = QUERY_SSP_TASK;
	else
		scb->header.opcode = INITIATE_SSP_TMF;

	scb->ssp_tmf.proto_conn_rate  = (1 << 4); /* SSP */
	scb->ssp_tmf.proto_conn_rate |= dev->linkrate;
	/* SSP frame header */
	scb->ssp_tmf.ssp_frame.frame_type = SSP_TASK;
	memcpy(scb->ssp_tmf.ssp_frame.hashed_dest_addr,
	       dev->hashed_sas_addr, HASHED_SAS_ADDR_SIZE);
	memcpy(scb->ssp_tmf.ssp_frame.hashed_src_addr,
	       dev->port->ha->hashed_sas_addr, HASHED_SAS_ADDR_SIZE);
	scb->ssp_tmf.ssp_frame.tptt = cpu_to_be16(0xFFFF);
	/* SSP Task IU */
	memcpy(scb->ssp_tmf.ssp_task.lun, lun, 8);
	scb->ssp_tmf.ssp_task.tmf = tmf;

	scb->ssp_tmf.sister_scb = cpu_to_le16(0xFFFF);
	scb->ssp_tmf.conn_handle= cpu_to_le16((u16)(unsigned long)
					      dev->lldd_dev);
	scb->ssp_tmf.retry_count = 1;
	scb->ssp_tmf.itnl_to = cpu_to_le16(ITNL_TIMEOUT_CONST);
	if (tmf == TMF_QUERY_TASK)
		scb->ssp_tmf.index = cpu_to_le16(index);

	res = asd_enqueue_internal(ascb, asd_tmf_tasklet_complete,
				   asd_tmf_timedout);
	if (res)
		goto out_err;
	wait_for_completion(&completion);

	switch (tcs.dl_opcode) {
	case TC_NO_ERROR:
		res = TMF_RESP_FUNC_COMPLETE;
		break;
	case TF_NAK_RECV:
		res = TMF_RESP_INVALID_FRAME;
		break;
	case TF_TMF_TASK_DONE:
		res = TMF_RESP_FUNC_FAILED;
		break;
	case TF_TMF_NO_TAG:
	case TF_TMF_TAG_FREE: /* the tag is in the free list */
	case TF_TMF_NO_CONN_HANDLE: /* no such device */
		res = TMF_RESP_FUNC_COMPLETE;
		break;
	case TF_TMF_NO_CTX: /* not in seq, or proto != SSP */
		res = TMF_RESP_FUNC_ESUPP;
		break;
	default:
		/* Allow TMF response codes to propagate upwards */
		res = tcs.dl_opcode;
		break;
	}
	return res;
out_err:
	asd_ascb_free(ascb);
	return res;
}

int asd_abort_task_set(struct domain_device *dev, u8 *lun)
{
	int res = asd_initiate_ssp_tmf(dev, lun, TMF_ABORT_TASK_SET, 0);

	if (res == TMF_RESP_FUNC_COMPLETE)
		asd_clear_nexus_I_T_L(dev, lun);
	return res;
}

int asd_clear_aca(struct domain_device *dev, u8 *lun)
{
	int res = asd_initiate_ssp_tmf(dev, lun, TMF_CLEAR_ACA, 0);

	if (res == TMF_RESP_FUNC_COMPLETE)
		asd_clear_nexus_I_T_L(dev, lun);
	return res;
}

int asd_clear_task_set(struct domain_device *dev, u8 *lun)
{
	int res = asd_initiate_ssp_tmf(dev, lun, TMF_CLEAR_TASK_SET, 0);

	if (res == TMF_RESP_FUNC_COMPLETE)
		asd_clear_nexus_I_T_L(dev, lun);
	return res;
}

int asd_lu_reset(struct domain_device *dev, u8 *lun)
{
	int res = asd_initiate_ssp_tmf(dev, lun, TMF_LU_RESET, 0);

	if (res == TMF_RESP_FUNC_COMPLETE)
		asd_clear_nexus_I_T_L(dev, lun);
	return res;
}

/**
 * asd_query_task -- send a QUERY TASK TMF to an I_T_L_Q nexus
 * task: pointer to sas_task struct of interest
 *
 * Returns: TMF_RESP_FUNC_COMPLETE if the task is not in the task set,
 * or TMF_RESP_FUNC_SUCC if the task is in the task set.
 *
 * Normally the management layer sets the task to aborted state,
 * and then calls query task and then abort task.
 */
int asd_query_task(struct sas_task *task)
{
	struct asd_ascb *ascb = task->lldd_task;
	int index;

	if (ascb) {
		index = ascb->tc_index;
		return asd_initiate_ssp_tmf(task->dev, task->ssp_task.LUN,
					    TMF_QUERY_TASK, index);
	}
	return TMF_RESP_FUNC_COMPLETE;
}