aboutsummaryrefslogtreecommitdiffstats
path: root/drivers/scsi/isci/task.c
blob: fb6eba331ac6eb9f51496682da04f50a33bdd063 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
/*
 * 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_AT_INITIATOR |
				    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,
					 SAM_STAT_TASK_ABORTED);
		} else {
			task->task_state_flags |= SAS_TASK_AT_INITIATOR;
			spin_unlock_irqrestore(&task->task_state_lock, flags);

			/* build and send the request. */
			status = isci_request_execute(ihost, idev, task, tag);

			if (status != SCI_SUCCESS) {
				spin_lock_irqsave(&task->task_state_lock, flags);
				/* Did not really start this command. */
				task->task_state_flags &= ~SAS_TASK_AT_INITIATOR;
				spin_unlock_irqrestore(&task->task_state_lock, flags);

				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) &&
	    (task->task_state_flags & SAS_TASK_AT_INITIATOR) &&
	    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))
						? "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_AT_INITIATOR |
					    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_AT_INITIATOR |
					    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_aca() - 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_aca(
	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.
 * @lun: This parameter specifies the lun associated with this request.
 *
 * 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.resp_iu,
			       &ireq->ssp.rsp,
			       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;
}